Anormalidades hematológicas en enfermedad hepática, fisiopatología y consideraciones terapéuticas / Hematologic disorders in liver failure: pathophysiology and therapeutic considerations

RESUMEN Las alteraciones en los recuentos celulares sanguíneos representan los hallazgos clínicos más notorios y recurrentes en pacientes que padecen enfermedad hepática, tanto aguda como crónica. Estos cambios constituyen un marcador importante de la disfunción hepática y, a menudo, desempeñan un papel crucial en la evaluación y manejo de estos pacientes. En conjunto con el alargamiento de las pruebas de coagulación, la trombocitopenia es la irregularidad más prevalente en estos individuos. Esta condición, así como las leucopenias, se le atribuye en gran medida al hiperesplenismo, una alteración en la que el bazo retiene y destruye las células sanguíneas, incluidas las plaquetas. Sin embargo, cuando el conteo plaquetario desciende por debajo de 10 x 103/µl, es fundamental considerar otras causas, como factores autoinmunitarios que pueden estar contribuyendo con la trombocitopenia. La anemia, definida como una disminución en el número de glóbulos rojos o en los niveles de hemoglobina, es otra característica constante que acompaña a la enfermedad hepática. Aunque en la mayoría de los casos la anemia es macrocítica, en algunas situaciones puede ser secundaria a eventos hemolíticos, como lo observado en el síndrome de Zieve. Esta diversidad en las manifestaciones de la anemia en pacientes hepáticos subraya la complejidad de las interacciones entre el hígado y los componentes sanguíneos. A pesar de los avances en la comprensión de las causas subyacentes de estas citopenias, las opciones del tratamiento siguen siendo limitadas. Generalmente, las opciones terapéuticas se enfocan en la administración de transfusiones de hemocomponentes para compensar las deficiencias en los recuentos celulares o en el uso de análogos de trombopoyetina (TPO) para estimular temporalmente la producción de las plaquetas en la medula ósea. No obstante, estos tratamientos tienden a abordar los síntomas más que las causas fundamentales de las alteraciones hematológicas en la enfermedad hepática. La persistencia y el empeoramiento de estas alteraciones pueden servir como indicadores tempranos de la progresión de la disfunción hepática. La relación intrincada entre el hígado y la homeostasis hematológica continúa siendo objeto de investigación, la compresión más profunda de estos mecanismos podría abrir potencialmente la puerta hacia enfoques terapéuticos más específicos y efectivos para abordar las citopenias en el contexto de la enfermedad hepática.

ABSTRACT Alterations in blood cell counts are the most prominent and recurrent clinical findings among patients suffering from both acute and chronic liver disease. These changes are an important marker of liver failure and often play a key role in the evaluation and management of these patients. Together with the prolongation of coagulation tests, thrombocytopenia is the most common disorder among these individuals. This condition, as well as leukopenia, is largely attributable to hypersplenism, a disorder in which the spleen retains and destroys blood cells, including platelets. However, when the platelet count drops below 10x103/µl, it is essential to consider other causes, such as autoimmune factors that may be contributing to the development of thrombocytopenia. Anemia, defined as a decrease in red blood cell count or hemoglobin levels, is another common characteristic of liver disease. Although in most cases macrocytic anemia occurs, in some situations it can be secondary to hemolytic events, as observed in Zieve's syndrome. This wide range of manifestations of anemia among liver patients highlights the complex interaction between liver and blood components. Despite advances in understanding the underlying causes of these cytopenias, treatment options remain limited. Therapeutic options generally focus on the transfusion of blood products to compensate for deficiencies in cell counts or on the use of thrombopoietin (TPO) analogues to temporarily stimulate platelet production in the bone marrow. However, these treatments tend to address the symptoms rather than the root causes of hematologic disorders in liver disease. The persistence and worsening of these disorders may serve as early indicators of the progression of liver failure. The complicated relationship between liver and hematological homeostasis remains the subject of research. A deeper understanding of these mechanisms could potentially open the door toward more targeted and effective therapeutic approaches to address cytopenias in the context of liver disease.

Conhecimento de graduandos sobre doação de medula óssea / Knowledge of undergraduates about bone marrow donation

Caracterizar o conhecimento dos graduandos de uma instituição de ensino superior acerca do processo de doação de medula óssea. Método: Trata-se de um estudo descritivo com abordagem quantitativa. Foram entrevistados 266 graduandos, de ambos os sexos, entre 17 e 21 anos de idade. Foi utilizado um questionário estruturado, contendo perguntas sobre o conhecimento a respeito do processo de doação de medula óssea. Resultados: A maioria dos participantes não conhece o processo de cadastro e doação de medula óssea, tendo como a falta de informação a principal causa para a desinformação a respeito do tema abordado, consequentemente resultando em pouca demanda para que mais pessoas sejam cadastradas no REDOME. Conclusão: os estudantes do ensino superior desconhecem os processos que envolvem desde ao cadastro até a doação de medula óssea, devido à desinformação e pouca divulgação sobre a temática. (AU)

To characterize the knowledge of undergraduates from a higher education institution about the bone marrow donation process. Method: This is a descriptive study with a quantitative approach. 266 undergraduates were interviewed, of both sexes, between 17 and 21 years old. A structured questionnaire was used, containing questions about their knowledge about the bone marrow donation process. Results: Most participants do not know the bone marrow registration and donation process, with lack of information being the main cause for misinformation about the topic addressed, consequently resulting in little demand for more people to be registered in REDOME. Conclusion: the higher education students are unaware of the processes that involve from registration to bone marrow donation, due to misinformation and little dissemination on the subject. (AU)

Caracterizar el conocimiento de estudiantes de grado de una institución de educación superior sobre el proceso de donación de médula ósea. Método: Se trata de un estudio descriptivo con abordaje cuantitativo. Se entrevistaron 266 estudiantes universitarios, de ambos sexos, entre 17 y 21 años. Se utilizó un cuestionario estructurado que contenía preguntas sobre el conocimiento sobre el proceso de donación de médula ósea. Resultados: La mayoría de los participantes desconocen el proceso de registro y donación de médula ósea, siendo la falta de información la principal causa de la desinformación sobre el tema abordado, por lo que se genera poca demanda para que más personas se registren en REDOME. Conclusión: los estudiantes de educación superior desconocen los procesos que involucran desde el registro hasta la donación de médula ósea, debido a la desinformación y poca difusión sobre el tema. (AU)

Resveratrol Alleviates Osteoporosis by Promoting Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells via SITR1/PI3K/AKT Pathway / El Resveratrol Alivia la Osteoporosis al Promover la Diferenciación Osteogénica de las Células Madre Mesenquimales de la Médula Ósea a Través de la Vía SITR1/PI3K/AKT

SUMMARY: Senile osteoporosis is mainly caused by reduced osteoblast differentiation and has become the leading cause of fractures in the elderly worldwide. Natural organics are emerging as a potential option for the prevention and treatment of osteoporosis. This study was designed to study the effect of resveratrol on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in osteoporosis mice. A mouse model of osteoporosis was established by subcutaneous injection of dexamethasone and treated with resveratrol administered by gavage. In vivo and in vitro, we used western blot to detect protein expression, and evaluated osteogenic differentiation of BMSCs by detecting the expression of osteogenic differentiation related proteins, calcium deposition, ALP activity and osteocalcin content. Resveratrol treatment significantly increased the body weight of mice, the level of serum Ca2+, 25(OH)D and osteocalcin, ration of bone weight, bone volume/total volume, trabecular thickness, trabecular number, trabecular spacing and cortical thickness in osteoporosis mice. In BMSCs of osteoporosis mice, resveratrol treatment significantly increased the expression of Runx2, osterix (OSX) and osteocalcin (OCN) protein, the level of calcium deposition, ALP activity and osteocalcin content. In addition, resveratrol treatment also significantly increased the expression of SIRT1, p-PI3K / PI3K and p-AKT / AKT in BMSCs of osteoporosis mice. In vitro, resveratrol increased the expression of SIRT1, p-PI3K / PI3K and p-AKT / AKT, Runx2, OSX and OCN protein, the level of calcium deposition, ALP activity and osteocalcin content in BMSCs in a concentration-dependent manner, while SIRT1 knockdown significantly reversed the effect of resveratrol. Resveratrol can attenuate osteoporosis by promoting osteogenic differentiation of bone marrow mesenchymal stem cells, and the mechanism may be related to the regulation of SIRT1/PI3K/AKT pathway.

La osteoporosis senil es causada principalmente por una diferenciación reducida de osteoblastos y se ha convertido en la principal causa de fracturas en las personas mayores en todo el mundo. Los productos orgánicos naturales están surgiendo como una opción potencial para la prevención y el tratamiento de la osteoporosis. Este estudio fue diseñado para estudiar el efecto del resveratrol en la diferenciación osteogénica de las células madre mesenquimales de la médula ósea (BMSC) en ratones con osteoporosis. Se estableció un modelo de osteoporosis en ratones mediante inyección subcutánea de dexametasona y se trató con resveratrol administrado por sonda. In vivo e in vitro, utilizamos Western blot para detectar la expresión de proteínas y evaluamos la diferenciación osteogénica de BMSC detectando la expresión de proteínas relacionadas con la diferenciación osteogénica, la deposición de calcio, la actividad de ALP y el contenido de osteocalcina. El tratamiento con resveratrol aumentó significativamente el peso corporal de los ratones, el nivel sérico de Ca2+, 25(OH)D y osteocalcina, la proporción de peso óseo, el volumen óseo/ volumen total, el espesor trabecular, el número trabecular, el espaciado trabecular y el espesor cortical en ratones con osteoporosis. En BMSC de ratones con osteoporosis, el tratamiento con resveratrol aumentó significativamente la expresión de las proteínas Runx2, osterix (OSX) y osteocalcina (OCN), el nivel de deposición de calcio, la actividad de ALP y el contenido de osteocalcina. Además, el tratamiento con resveratrol también aumentó significativamente la expresión de SIRT1, p-PI3K/PI3K y p-AKT/AKT en BMSC de ratones con osteoporosis. In vitro, el resveratrol aumentó la expresión de las proteínas SIRT1, p-PI3K/PI3K y p- AKT/AKT, Runx2, OSX y OCN, el nivel de deposición de calcio, la actividad de ALP y el contenido de osteocalcina en BMSC de manera dependiente de la concentración, mientras que La caída de SIRT1 revirtió significativamente el efecto del resveratrol. El resveratrol puede atenuar la osteoporosis al promover la diferenciación osteogénica de las células madre mesenquimales de la médula ósea, y el mecanismo puede estar relacionado con la regulación de la vía SIRT1/PI3K/AKT.

Tuberculosis extrapulmonar: Presentación atípica de compromiso de la médula ósea / Extrapulmonary Tuberculosis: Unusual Presentation with Bone Marrow Involvement

RESUMEN La primera causa de muerte por enfermedad infecto-contagiosa a nivel mundial es atribuible a la infección por Mycobacterium tuberculosis. La tuberculosis extrapulmonar representa entre un 20 % y un 25 % de los casos de enfermedad tuberculosa. Frecuentemente, para arribar al diagnóstico de dichas localizaciones, se debe recurrir a pruebas diagnósticas invasivas Se presenta el caso de un paciente de 17 años de edad con compromiso extrapulmo nar de tuberculosis en médula ósea sin inmunocompromiso conocido, con síntomas de fiebre, astenia, pérdida de peso, tricitopenia y hepatoesplenomegalia, sin otros hallazgos clínicos significativos. Se arriba al diagnóstico por cultivo positivo para tuberculosis en material de punción/ biopsia de médula ósea. Luego de un mes de tratamiento con isoniacida, pirazinamida, etambutol y rifampicina evoluciona con registros febriles aún después de recibir antibióticos por infección urinaria por Klebsiella pneumoniae, por lo cual se inicia corticoterapia oral con buena respuesta. El paciente abandona el tratamiento luego de tres meses y medio por mala adherencia a este.

ABSTRACT The leading cause of death from a contagious infectious disease worldwide is attribut able to Mycobacterium tuberculosis infection. Extrapulmonary tuberculosis accounts for 20-25 % of cases of tuberculous disease. Frequently, in order to reach the diagnosis of these sites, invasive diagnostic tests have to be used. We present the case of a 17-year-old patient with extrapulmonary tuberculosis with bone marrow involvement. The patient wasn't immunocompromised, and had the following symptoms: fever, asthenia, weight loss, tricytopenia and hepatosplenomegaly, without other significant clinical findings. The diagnosis was reached by positive culture for tuberculosis in bone marrow puncture aspiration/biopsy material After one month of treatment with isoniazid, pyrazinamide, ethambutol and rifampicin, the patient evolved with fever episodes, even after having received antibiotics for urinary tract infection caused by Klebsiella pneumoniae. Thus, oral corticosteroid therapy was started, with good response. The patient discontinued treatment after three and a half months due to poor adherence.

Effect of lumbar bone marrow composition on bone marrow diffusion signal intensity and apparent diffusion coefficient in healthy adult women / 重庆医学

Objective To analyze the effect of lumbar bone marrow composition on bone marrow diffu-sion-weighted imaging(DWI)in healthy adult women.Methods Retrospective analysis was performed on up-per abdominal MRI of 103 adult women.Bone marrow fat fraction of lumbar vertebra was measured according to two-point water-lipid separation technique,and apparent diffusion coefficient(ADC)value of lumbar verte-bra was measured according to DWI image(b=800 s/mm2).The subjects were divided into the high-signal group and the equal-low-signal group according to the signal intensity of lumbar vertebra and adjacent erector spine muscles.The effects of age,lumbar bone marrow fat fraction and menstrual status on the signal intensity and ADC value of lumbar bone marrow diffusion were analyzed.Finally,the correlation between lumbar bone marrow fat fraction and ADC value was analyzed.Results Univariate analysis showed that the lumbar bone marrow diffusion signal intensity and ADC value were affected by age,lumbar bone marrow fat fraction and menstrual status(P＜0.001).Multivariate analysis showed that age(P=0.046)and lumbar bone marrow fat fraction(P=0.005)were the influencing factors of lumbar bone marrow diffusion signal intensity,but men-strual status(P=0.242)was not the influencing factor.In addition,lumbar bone marrow fat fraction(P＜0.001)was the factor influencing the ADC value of lumbar bone marrow,and the two were negatively correla-ted(r=-0.607,P＜0.001),but age(P=0.497)and menstrual status(P=0.082)were not the influencing factors.Conclusion The bone marrow composition of lumbar vertebrae in healthy adult women has significant effects on the signal intensity and ADC value of bone marrow diffusion.

Effect and mechanism of transplantation bone marrow stromal stem cells transfected NRG1 gene on repair of hemi-transected spinal cord injury in rats / 解放军医学杂志

Objective To investigate the effect and mechanism of transplantation of neuregulin1(NRG1)gene-modified bone marrow mesenchymal stem cells(BMSCs)on the repair of hemi-transected spinal cord injury(SCI)in rats.Methods Isolated and cultured rat BMSCs,followed by transfection with the NRG1 gene.The levels of NRG1 in BMSCs lysate and culture supernatant was deected by ELISA method,and the proliferation activity of the BMSCs was detected by cell counting method.Forty-three healthy 8-week-old SD rats were randomly divided into control group(n=10),SCI model group(n=10),BMSCs group(n=10),and NRG1-BMSCs group(n=13).After establishing the spinal cord hemisection model,animals received in-situ transplantation of BMSCs or NRG1-BMSCs.On the 1,7,14,21,and 28 days after transplantation,the hind limb motor function was evaluated using BBB score and inclined plate test;on the 7th day after transplantation,the migration and distribution of transplanted cells was monitored using a fluorescence microscope;on the 28th day after transplantation,the pathological changes of rat spinal cord tissues was examined using HE staining and Nissl staining;cell apoptosis using TUNEL staining,and levels of endoplasmic reticulum stress-related proteins[X-box binding protein 1(XBP1),C/EBP homologous protein(CHOP),activating transcription factor 4(ATF4),ATF6,glucose-regulated protein 78(GRP78)]and apoptosis-related proteins[B-cell lymphoma-2(Bcl-2)and Bcl-2-associated protein X(Bax)]in rat spinal cord tissues using Western blotting.Results BMSCs were successfully isolated,cultured,and transfected with the NRG1 gene.ELISA method results showed that the NRG1 contents in the NRG1-BMSCs lysate and culture supernatant were significantly higher than that of BMSCs in a time-dependent manner(P<0.05).The proliferation activity of NRG1-BMSCs was significantly higher than that of BMSCs(P<0.05).On the 21 and 28 days after transplantation,the BBB score and the slope angle of the inclined plate in NRG1-BMSCs group were higher than those in SCI model group or BMSCs group(P<0.05).However,it did not reverse to the level in control group(P<0.05).On the 28th day after transplantation,compared with the SCI model group and BMSCs group,neuronal pyknosis reduced,the Nissl body density increased,the expression levels of XBP1,CHOP,ATF4,ATF6,GRP78,and Bax,and the rate of TUNEL-positive cells significantly reduced in NRG1-BMSCs group(P<0.05),and the expression level of Bcl-2 significantly increased(P<0.05).Conclusion Transplantation of NRG1 gene-modified BMSCs can alleviate SCI and improve the recovery of motor function in rats.The mechanism may be related to promoting the proliferation activity of BMSCs,inhibiting cell apoptosis,and mitigating endoplasmic reticulum stress.

Pathological characteristics of angioimmunoblastic T cell lymphoma with bone marrow involvement / 临床与实验病理学杂志

Purpose To explore the pathological features of angioimmunoblastic T-cell lymphoma(AITL)with bone marrow involvement and to improve awareness of bone marrow infiltration in AITL.Methods The tissue morphology of 32 cases of AITL with bone marrow involvement was retrospectively analyzed.Im-munohistochemistry using the EnVision method and ten-color flow cytometry were conducted to detect AITL-related immune markers.T cell clonality was analyzed through T cell receptor(TCR)gene rearrangement.Results The predominant pat-terns of tumor cell infiltration were nodular(20/32,62.5％)and interstitial or small clusters(10/32,31.3％).The nodules showed a mixture of cellular components.In some cases,the fo-ci contained a mixture of cells with characteristic"granuloma-toid"changes.The tumor cells were mainly small to medium-sized lymphocytes with inconspicuous atypia.Some cases showed plasma cell proliferation.19 cases were subject to immunohisto-chemical staining,which revealed a low count of CD4-positive T cells,with an average of 8.4％.The positive rates of T follic-ular helper cells(TFH)markers were as follows:CD10(7/14,50.0％),BCL6(6/19,31.6％),PD-1(13/19,68.4％),and CXCL13(13/19,68.4％).In most cases,tumor cells showed co-expression of PD-1 and CXCL13,but the number of positive cells was less than 1％.Flow cytometry analysis was performed in 24 cases,among which 22 cases all consistently expressed cytoplasmic CD3(cCD3),CD5,CD4,and CD2,with varying degrees of CD10 expression.In some cases,there was a lack of expression of surface CD3(sCD3)(12/22,54.5％),while there was a lack of expression of CD7(8/22,36.4％).and no abnormal T cells were found in 2 cases.TCR gene rearrangement analysis was performed in 7 cases,with 3 cases showing TCR clonality.Conclusion AITL with bone marrow involvement exhibits a lower proportion of tumor cells and less atypia,making it prone to misdiagnosis.The presence of lymphocytic foci with mixed cellular components in the bone marrow can indicate bone marrow involvement in AITL.Flow cy-tometry detection of abnormal T cells(double positive for CD4 and CD10)strongly suggests bone marrow infiltration in AITL.A comprehensive diagnosis of bone marrow involvement in AITL re-quires consideration of bone marrow biopsy,flow cytometry,and TCR gene rearrangement analysis.

Zoledronic acid affects osteogenic differentiation and bone formation by regulating the expression of SIRT3/P53 / 中华内分泌外科杂志

Objective:To explore the mechanism of zoledronic acid (ZOL) affects osteogenic differentiation and bone formation through the regulation of sirtuin 3 (SIRT3) / P53 expression.Methods:Bone marrow mesenchymal stem cells (BMSCs) were induced to differentiate into osteogenic cells, the expression of SIRT3 in the cells was detected, and the targeting regulation relationship between SIRT3 and P53 was analyzed. The intracellular expressions of SIRT3 and P53 were intervened and ZOL was used to treat the cells. MTT method, Western blot method and kit were used to detect cell viability, osteogenesis-related genes Osteoprotegerin (OPG), runt-related transcription factor 2 (Runx2) expression, alkaline phosphatase (ALP) activity and alizarin red S (ARS) staining, respectively. Ovariectomy (OVX) was used to construct a rat model and explore the effect of ZOL on the progression of osteoporosis (OP) in vivo.Results:ZOL promoted osteogenic differentiation of BMSCs. The expression of SIRT3 was down-regulated in the serum of OP patients (0.78±0.23) compared with that of healthy subjects (1.00±0.26 vs. 0.78±0.23. t=3.85, P<0.001). During the osteogenic differentiation of BMSCs, the expression level of SIRT3 gradually increased with the prolonged induction of osteogenesis. Compared with the p53 protein expression and BMSCs activity in the control group, SIRT3 knockout could increase the expression level of p53 protein (0.59±0.05 vs. 1.01±0.11. t=6.02, P=0.004) but inhibited the activity of BMSCs (100.00±8.41 vs. 51.26±5.59. t=8.36, P=0.001). After ZOL treatment, the inhibitory effect of SIRT3 on cell viability (49.61±5.11 vs. 87.61±7.31. t=7.38, P=0.002) and osteogenesis was relieved, and the level of P53 was inhibited (1.10±0.10 vs. 0.69±0.04. t=6.59, P=0.003). P53 overexpression partially offseted the effects of ZOL on cell viability (84.61±6.52 vs. 66.54±5.47. t=3.68, P=0.021) and osteogenesis. Compared with the sham surgery group, the OVX group showed inhibition of osteogenesis in rats, and ZOL treatment significantly improved osteogenic inhibition. ZOL treatment increased the expression level of SIRT3 protein in bone tissue of OVX rats, but inhibited the expression level of P53. Conclusion:ZOL promoted osteogenic differentiation and bone formation of BMSCs by promoting the ubiquitination and degradation of P53 by SIRT3.

Analysis on the Effects of PPARγ Gene-silenced Human Bone Marrow Stromal Cells on Hematopoietic Function in Mice with Bone Marrow Suppression / 华中科技大学学报(医学版)

Objective To investigate the effects of peroxisome proliferator activated receptor-gamma(PPARγ)gene silen-cing in human bone marrow stromal cells(HS-5)on hematopoietic function in bone marrow-suppressed mice,and to explore the potential mechanisms involved.Methods A bone marrow-suppressed mouse model was established by whole-body X-ray irradi-ation.Two hours after modeling,the mice were randomly divided into three groups:experimental group(intravenous injection of PPARγ RNAi-interfered HS-5 cells through the tail vein),control group(intravenous injection of PPARγ RNAi-uninterfered HS-5 cells through the tail vein),and blank group(intravenous injection of an equal amount of saline through the tail vein),with 5 mice in each group.Peripheral blood routine tests were performed before,24 hours after,1 week after,and 2 weeks after radio-therapy.In vitro osteogenic and adipogenic induction was performed in cells,and the cells were divided into experimental group(PPARγ RNAi-interfered HS-5 cells),control group(PPARγ-uninterfered HS-5 cells),and blank group(HS-5 cells without os-teogenic/adipogenic induction).Osteogenic/adipogenic staining was observed.The effects of PPARγ gene-silenced HS-5 cells on mouse bone marrow hematopoietic stem cells(HSCs)were detected by CCK-8 proliferation assay.The groups included experi-mental group(PPARγ RNAi-interfered HS-5 cells were co-cultured with mouse HSCs after 3 days of osteogenic induction dif-ferentiation),positive control group(HS-5 cells treated with 50 μmol/L PPARγ inhibitor were co-cultured with mouse HSCs af-ter 3 days of osteogenic induction differentiation),negative control group(PPARγ RNAi-uninterfered HS-5 cells were co-cul-tured with mouse HSCs after 3 days of osteogenic induction differentiation),and blank group(Mouse HSCs were cultured alone without co-culturing with HS-5 cells).Results After radiotherapy,the hematological parameters of mice in each group showed a decreasing trend initially,and then increased.One week after radiotherapy,there were significant differences in platelet and white blood cell levels among the three groups(experimental group＞control group＞blank group,all P＜0.05).Two weeks after radiotherapy,there were significant differences in the percentage of adipocyte vacuole area among the three groups(experi-mental group＜control group＜blank group,all P＜0.05).Pearson correlation analysis showed a negative correlation between hematological parameters and PPARγ expression levels(all P＜0.05),as well as a negative correlation between hematological parameters and the percentage of adipocyte vacuole area(all P＜0.05).After in vitro osteogenic/adipogenic induction differenti-ation,compared to the control group,the experimental group showed a significantly lower proportion of orange-red cells and a significantly higher proportion of red calcium nodules.After 3 days of osteogenic induction differentiation,the experimental group,positive control group,and negative control group of human bone marrow stromal cells were co-cultured with mouse HSCs,while HSCs were solely cultured in the blank group.The results showed that after 24 h,48 h and 72 h of co-culture,the A values of mouse HSC cells in the experimental group and positive control group were higher than those in the negative control group and blank group(all P＜0.05).Conclusion Silencing of the PPARγ gene in HS-5 cells implanted into bone marrow-sup-pressed mice contributes to enhanced hematopoietic function in mice.After interference and silencing of the PPARγ gene,the os-teogenic differentiation ability of HS-5 cells is enhanced,while the adipogenic differentiation ability is weakened.Furthermore,osteogenic-induced HS-5 cells can further enhance the proliferation capacity of mouse HSCs.

Study on the effect and mechanism of bone marrow mesenchymal stem cells on apoptosis of peritoneal mesothelial cells / 天津医药

Objective To observe the effect of rat bone marrow mesenchymal stem cells(BMSCs)on the apoptosis of rat peritoneal mesothelium cells(PMCs)induced by high glucose peritoneal dialysis fluid(PDF),and to explore its possible molecular mechanism.Methods The primary BMSCs and PMCs were extracted and identified.Apoptosis of PMCs was induced by high glucose PDF.Cell supernatant from BMSCs after 24 h of culture was collected as the conditioned medium(BMSCs-CM).PMCs were co-cultured with BMSCs by conditioned media or Transwell chambers.PMCs were randomly divided into the control group,the PDF group and the PDF+BMSCs-CM group.The viability of PMCs was measured by CCK-8 in each group.The depolarization of mitochondrial membrane potential was measured by JC-1 method.TUNEL staining was used to detect cell apoptosis.Western blot assay was used to detect the expression levels of apoptosis related proteins B-cell lymphoma-2(Bcl-2),Bcl-2 associated X protein(Bax),Cleaved cysteine aspartase-3(Cleaved Caspase-3)and pathway related protein serine/threonine protein kinase(Raf),mitogen-activated extracellular signal-regulated kinase(MEK),extracellular-signal regulated protein kinase(ERK)and their phosphorylated proteins in each group.Results Compared with the control group,the proliferative activity and mitochondrial membrane potential of PMCs were decreased in the PDF group,while the apoptosis rate and the ratio of Bax/Bcl-2,Cleaved Caspase-3/Caspase-3,p-Raf/Raf,p-MEK/MEK and p-ERK/ERK were increased(P＜0.05).Compared with the PDF group,the proliferative activity and mitochondrial membrane potential of PMCs were increased in the PDF+BMSCs-CM group,while the apoptosis rate and the ratio of Bax/Bcl-2,Cleaved Caspase-3/Caspase-3,p-Raf/Raf,p-MEK/MEK and p-ERK/ERK were decreased(P＜0.05).Conclusion BMSCs can reduce the apoptosis of PMCs induced by high glucose PDF,and its mechanism maybe related to inhibiting the activation of Raf/MEK/ERK signaling pathway.

Comparative study on the directed differentiation ability of mouse bone marrow and adipose-derived mesenchymal stem cells / 天津医药

Objective To investigate the targeted differentiation ability of mouse bone marrow derived mesenchymal stem cells(BM-MSCs)and adipose-derived mesenchymal stem cells(AD-MSCs).Methods BM-MSCs and AD-MSCs were isolated and cultured from bone marrow of femur and white adipose tissue of groin of C57BL/6J mice respectively,and the two types of cells were induced by osteogenic,chondrogenic and adipogenic differentiation medium respectively.Alizarin red,alcian blue and oil red O staining were used to detect the differentiated degree of osteogenic,chondrogenic and lipogenic differentiation.Real-time fluorescence quantitative PCR(qPCR)was used to identify MSCs and detected expression levels of directed differentiation-related genes Runx2,Sp7(osteoblast),Sox9,Col2a1(chondroblast),Pparg and Cebpa(lipogenesis)to determine the directed differentiation ability of cells.Based on gene expression profiles of mouse and human BM-MSCs and AD-MSCs in GEO database GSE43804 and GSE122778,the differentially expressed genes and their enrichment signal pathways were analyzed.Results The cell morphology of BM-MSCs and AD-MSCs obtained by isolation and culture was different,and spindle-shaped morphology was more obvious in AD-MSCs.Both cells expressed CD29,CD44 and CD90,but did not express CD34 and CD45.AD-MSCs showed higher osteogenic and lipogenic differentiation than those of BM-MSCs after directed induction,while chondrogenic differentiation was lower in AD-MSCs than that of BM-MSCs(P＜0.05).After directional induction,expression levels of Runx2,Pparg and Cebpa mRNA were higher in AD-MSCs than those in BM-MSCs,and Sox9 mRNA expression levels were lower than those in BM-MSCs(P＜0.05).Highly expressed genes of AD-MSCs in mice and human were enriched in PPAR and WNT signaling pathways.Highly expressed genes of BM-MSCs were enriched in cartilage and bone developmental signaling pathways.Conclusion The osteogenic and adipogenic differentiation ability of mouse AD-MSCs is stronger than those of BM-MSCs,while the chondrogenic differentiation ability AD-MSCs is weaker than that of BM-MSCs.The activation status of PPAR,WNT,cartilages and skeletal system development signaling pathways plays an important regulatory role in determining the different directional differentiation potential of AD-MSCs and BM-MSCs.

Effect of lentiviral silencing of Piezo1 on osteogenic differentiation and TAZ expression in human bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND:Piezo1,a mechanosensitive protein,is tightly connected to osteogenic differentiation,and it has been demonstrated that TAZ has a role in regulating osteogenic differentiation.It is unclear whether TAZ participates in the regulation of osteogenic differentiation of human bone marrow mesenchymal stem cells by Piezo1,so it is crucial to investigate its unique mechanism to prevent osteonecrosis of the femoral head. OBJECTIVE:To elucidate what function Piezo1 plays in osteogenic differentiation and TAZ expression in human bone marrow mesenchymal stem cells. METHODS:The siRNA targeting Piezo1 was constructed and transfected into 293T cells.The silencing efficiency was detected by RT-qPCR.The selected Piezo1-Home-2337 was packaged according to the silencing efficiency,and its optimal multiplicity of infection value was assayed by immunofluorescence staining.The packaged Piezo1 silencing recombinant lentivirus was transfected into human bone marrow mesenchymal stem cells,and its silencing effect was detected by RT-qPCR and western blot assay.Alizarin red staining,alkaline phosphatase activity analysis,immunofluorescence staining,RT-qPCR and western blot assay were utilized to analyze the effect of silencing Piezo1 on the osteogenic differentiation of human bone marrow mesenchymal stem cells. RESULTS AND CONCLUSION:(1)The mRNA and protein levels of Piezo1 in human bone marrow mesenchymal stem cells transfected by si-Piezo1 were decreased significantly,with a statistically significant difference compared with normal and negative control groups.(2)The alkaline phosphatase activity in the si-Piezo1 group was much lower and the calcium deposition in the si-Piezo1 group was significantly reduced compared with the negative control group.(3)The mRNA levels of osteogenesis-related genes including Runt-related transcription factor 2(Runx2),osteopontin(OPN),distal-less homeobox 5(DLX5),osteocalcin,β-catenin and Tafazzin(TAZ)in the si-Piezo1 group were significantly decreased compared with the negative control group.Afterward,the expression levels of TAZ and β-catenin protein in the si-Piezo1 group were down-regulated significantly compared with the negative control group,whereas the expression levels of p-TAZ and p-β-catenin protein in the si-Piezo1 group had the opposite condition.(4)The results of immunofluorescence staining showed that the expression of TAZ and β-catenin in human bone marrow mesenchymal stem cells in the si-Piezo1 group was less compared with the negative control group.(5)These findings indicate that Piezo1 can promote the osteogenic differentiation of human bone marrow mesenchymal stem cells.The osteogenic ability of human bone marrow mesenchymal stem cells is significantly reduced after silencing Piezo1,and the expression of TAZ is also reduced.

Irisin alleviates palmitic acid-induced osteogenic inhibition in bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND:Irisin,a myokine isolated from the transmembrane protein FNDC5 by muscle cells during exercise,has the function of inducing the browning of white adipose tissue,but its effect on lipotoxicity-induced osteogenic differentiation and the mechanism is unclear. OBJECTIVE:To investigate the effect of irisin on the osteogenic ability of palmitic acid-induced bone marrow mesenchymal stem cells and the mechanism of action. METHODS:CCK-8 assay was used to detect the effect of different concentrations of palmitic acid on the proliferation of mouse bone marrow mesenchymal stem cells and the effect of irisin on the proliferation of mouse bone marrow mesenchymal stem cells in the presence of palmitic acid.After pretreatment with irisin and palmitic acid for 24 hours,osteogenic differentiation of mouse bone marrow mesenchymal stem cells was induced by alkaline phosphatase staining as well as qRT-PCR was performed to detect the expression of osteogenesis-related genes on day 7 of osteogenic induction culture.The expression of proteins related to the AMPK/BMP2/SMAD signaling pathway was detected by western blot assay.Alizarin red staining was conducted on day 21 to detect osteogenic differences. RESULTS AND CONCLUSION:(1)The CCK-8 assay results suggested that the amplification of bone marrow mesenchymal stem cells was inversely proportional to the concentration of palmitic acid,but at 0.02 mmol/L concentration,palmitic acid had no significant effect on the amplification of bone marrow mesenchymal stem cells,and irisin did not affect the proliferation of bone marrow mesenchymal stem cells when its mass concentration was in the range of 0.1-20 μg/L.(2)Alkaline phosphatase staining and alizarin red staining showed that palmitic acid inhibited the osteogenic differentiation ability of bone marrow mesenchymal stem cells.Irisin improved palmitic acid-induced osteogenic inhibition of bone marrow mesenchymal stem cells.qRT-PCR results showed that palmitic acid could cause the downregulation of osteogenic-related genes,and irisin could inhibit this trend.(3)Western blot assay results showed that compared with the palmitic acid intervention group,irisin treatment enhanced AMPK/BMP2/SMAD signal transduction in bone marrow mesenchymal stem cells.It is found that irisin can improve the osteogenic differentiation ability of bone marrow mesenchymal stem cells pretreated with palmitic acid,and proposed that the specific mechanism might be mediated by AMPK/BMP/SMAD signaling pathway.

Mechanism underlying rat hepatocyte apoptosis regulated by exosomes derived from bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND:Bone marrow mesenchymal stem cells(BMSCs)can release a large number of exosomes(Exos).The effect of Exos derived from BMSCs on hepatocyte apoptosis and the specific mechanism has not been fully clarified. OBJECTIVE:To explore the effect of miR-21-5p carried by Exos derived from BMSCs on apoptosis of rat liver cells and its mechanism. METHODS:Rat BMSCs were isolated and miR-21-5p NC or miR-21-5p inhibitor was transfected into BMSCs.The Exos were extracted by ultracentrifugation and named(BMSCs+miR-21-5p NC)-Exos and(BMSCs+miR-21-5p inhibitor)-Exos.BMSCs-derived Exos were co-cultured with rat hepatocytes to observe the effect of inhibiting miR-21-5p expression on the apoptosis of rat hepatocytes.The targeting relationship between miR-21-5p and PIK3R1 was verified by double luciferase reporter gene detection.TUNEL was used to detect the effect of miR-21-5p directly targeting PIK3R1 in Exos to activate the PI3K/AKT signaling pathway on hepatocyte apoptosis in BRL rats. RESULTS AND CONCLUSION:(1)The double luciferase reporting system confirmed that when PI3KR1 wild type vector and miR-21-5p mimics co-transfected 293T cells,the luciferase activity decreased significantly compared with the PI3KR1 mutant vector co-transfected group,indicating that miR-21-5p could target PIK3R1.(2)TUNEL test results showed that compared with(BMSCs+miR-21-5p NC)-Exos group,(BMSCs+miR-21-5p inhibitor)-Exos treatment significantly increased the apoptosis rate.Compared with the(BMSCs+miR-21-5p NC)-Exos group,after the addition of AKT inhibitor LY294002,the apoptosis rate was significantly increased.(3)The results indicate that Exos may inhibit the apoptosis of BRL rat hepatocytes through miR-21-5p,in which miR-21-5p directly targets PIK3R1 to activate PI3K/AKT signaling pathway.

Characteristics,advantages and application of osteogenic differentiation of jaw bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND:The repair of maxillofacial bone tissue defects is a hot and difficult point in current research and the selection of seed cells is the key.Jaw bone marrow mesenchymal stem cells are adult mesenchymal stem cells that exist in the jaw bone.They have advantages in the application of maxillofacial tissue regeneration. OBJECTIVE:To summarize the biological characteristics,osteogenic differentiation advantages of jaw bone marrow mesenchymal stem cells,and the effects of drugs,in vivo environment,and microRNAs on the osteogenic differentiation of jaw bone marrow mesenchymal stem cells. METHODS:Computers were used to perform literature retrieval in PubMed and CNKI.Chinese and English search terms were"oral,bone tissue engineering,stem cells".405 articles were retrieved and downloaded.The articles were screened according to the inclusion and exclusion criteria and 70 articles were finally included for literature review. RESULTS AND CONCLUSION:Jaw bone marrow mesenchymal stem cells were excellent seed cells for oral bone tissue engineering,and had good proliferation and osteogenic differentiation potential.Drugs,in vivo environment and microRNAs could regulate the osteogenic differentiation of jaw bone marrow mesenchymal stem cells.However,the research on jaw bone marrow mesenchymal stem cells was still in the initial stage,so more research with strong demonstration is needed to confirm that jaw bone marrow mesenchymal stem cells have more advantages in the application of maxillofacial bone tissue regeneration.

Hyaluronic acid hydrogel-encapsulated bone marrow mesenchymal stem cells promote cardiac function in myocardial infarction rats(Ⅲ) / 中国组织工程研究

BACKGROUND:Our previous experimental results have shown that hyaluronic acid hydrogel can act as a vehicle for bone marrow mesenchymal stem cell delivery to improve the cardiac function of rats with myocardial infarction. OBJECTIVE:To explore the molecular mechanism of bone marrow mesenchymal stem cells and hyaluronic acid hydrogel in promoting damaged heart repair. METHODS:Bone marrow mesenchymal stem cells from male Sprague-Dawley rats were isolated and cultured,and then hyaluronic acid-encapsulated bone marrow mesenchymal stem cells were cultured in vitro in a three-dimensional manner.A model of myocardial infarction was made by ligating the left anterior descending artery of female Sprague-Dawley rats.After 1 week,the model rats were screened by ultrasonic testing and then eligible ones were randomly divided into four groups:PBS group(n=12),hyaluronic acid group(n=12),bone marrow mesenchymal stem cell group(n=15),and hyaluronic acid-encapsulated bone marrow mesenchymal stem cell group(n=15).At 1 week after ligation,the model rats underwent the secondary thoracotomy followed by corresponding injections into the infarcted region and its marginal zone.The expression levels of matrix metalloproteinase-2,vascular endothelial growth factor,thymosin β4 and c-Kit were examined at post-injection day 1,week 1 and week 2 by western blot assay.At post-injection week 2,immunofluorescence staining was used to detect the differentiation of transplanted cells. RESULTS AND CONCLUSION:(1)The expression levels of matrix metalloproteinase-2 and vascular endothelial growth factor protein in the infarct zone in the bone marrow mesenchymal stem cell group were significantly up-regulated at week 1 compared with the other three groups(P<0.05).At week 2,the hyaluronic acid group had a lower expression of matrix metalloproteinase-2 and vascular endothelial growth factor protein than the other three groups(P<0.05).However,the expression of matrix metalloproteinase-2 and vascular endothelial growth factor protein in the hyaluronic acid+bone marrow mesenchymal stem cell group was not significantly different compared with the bone marrow mesenchymal stem cell group.This was primarily attributable to a prolonged paracrine effect via the controlled release of the hyaluronic acid hydrogel.This prolonged paracrine effect offsets the inhibitory effect induced by hyaluronic acid hydrogel at 2 weeks.(2)Compared with the PBS group,thymosin β4 and c-Kit expression levels in the hyaluronic acid group,bone marrow mesenchymal stem cell group and bone marrow mesenchymal stem cell+hyaluronic acid group were significantly increased(P<0.05).(3)No differentiation of transplanted cells into cardiomyocytes or blood vessels was detected 2 weeks after transplantation.(4)It is indicated that transplanted bone marrow mesenchymal stem cells promote myocardial repair through the paracrine effect,and hyaluronic acid hydrogel prolongs the paracrine effect of transplanted bone marrow mesenchymal stem cells.

Strategy and significance of Chinese medicine combined with medical hydrogel for disease treatment / 中国组织工程研究

BACKGROUND:Medical hydrogels are new functional polymer materials with three-dimensional structural networks and excellent biocompatibility,which have been widely studied in the field of tissue engineering and drug carriers,but the research on the combination of medical hydrogels and Chinese medicine for the treatment of diseases based on tissue engineering is still in the early exploration stage.Therefore,through the analysis of the mechanism of the role of medical hydrogels,the integration of medical hydrogels and Chinese medicine in the research of the joint application of the article,can better provide ideas for scientific researchers,and the joint application of Chinese medicine and medical hydrogels is of great significance. OBJECTIVE:To explore the strategy and significance of Chinese medicine combined with medical hydrogel for disease treatment based on tissue engineering research. METHODS:PubMed and CNKI were used to retrieve articles about the application of Chinese medicine combined with medical hydrogel in tissue engineering from January 2010 to November 2022,with the Chinese and English search terms"hydrogel,traditional Chinese medicine,drug carrier,tissue engineering".After the initial screening of all articles according to the inclusion and exclusion criteria,the 61 articles with high relevance were retained for review. RESULTS AND CONCLUSION:(1)Although the application of Chinese medicine combined with medical hydrogel is involved in intra-articular,intra-tissue organ,soft tissue wounds,tissue engineering,etc.,except for the clinical application of Chinese medicine combined with hydrogel dressing for soft tissue injury,other aspects are still in the experimental stage.(2)The development of Chinese medicine combined with medical hydrogel has great potential and development prospects,but there is a certain difficulty in the manufacture of the gel with high-performance requirements,and it is difficult to master the physical and chemical properties precisely.(3)At present,the comprehensive view of injectable hydrogel with the characteristics of easy to use,its joint use of Chinese medicine can be extended to a wider range,can be used for joint,organ,tissue engineering-related disease treatment.Smart hydrogel has high sensitivity and reversible transformation can also meet the use of the special environment.During the combined use of Chinese medicine,it also needs to understand the mechanism of action of Chinese medicine components.(4)The strategy of combining Chinese medicine with medical hydrogels for disease treatment should start with matching the therapeutic effects of Chinese medicine on organs,tissues and cells combined with appropriate types of medical hydrogels to make up for the shortcomings of traditional Chinese medicine delivery methods and frequent drug delivery.In tissue engineering,hydrogels can be loaded with stem cells after Chinese medicine intervention,or with both Chinese medicine and stem cells for disease treatment.(5)In future research of combined Chinese medicine and medical hydrogel application,we also need to consider:we should ensure that the biological properties of medical hydrogel can be quantified,and grasp the characteristics of hydrogel with different manufacturing processes of different materials to produce the required medical hydrogel that meets the application conditions.In Chinese medicine,we need to comprehensively understand and analyze the therapeutic effects and application mechanisms of known Chinese medicine monomer and Chinese medicine compound extracts,so as to achieve a more perfect combination between Chinese medicine and medical hydrogel under a more clear mechanism.With the continuous improvement of medical science and technology innovation,the medical hydrogel can be innovatively combined with other traditional treatment methods of Chinese medicine,such as acupuncture,massage,cupping and so on,to be used from multiple angles.

In vitro experiment of stem cell engineered two-sided anisotropic electrospun membranes for promoting dural repair / 中国组织工程研究

BACKGROUND:Currently,the dura mater is clinically repaired using autologous tissue or materials such as gelatin sponge,but all of them have their inherent defects.Therefore,there is an urgent need for a biomaterial that can promote dural repair. OBJECTIVE:The two-sided anisotropic electrospun membrane was constructed by using directional electrospinning technology and collagen self-assembly technology,and was used as a carrier for bone marrow mesenchymal stem cells to investigate various physicochemical properties and biological characteristics of the artificial dura mater. METHODS:Ordered polylactic acid electrospun fibers with double-sided(collagen protein on one side and polylactic acid on the other side)anisotropic electrospun membranes(collagen group),disordered polylactic acid electrospun membranes(disordered fiber group),and ordered oriented polylactic acid electrospun membranes(ordered fiber group)were prepared by electrospinning technique as well as collagen self-assembly technique.Scanning electron microscopy,mechanical stretching,water contact angle testing,and degradation experiments were used to characterize the physicochemical properties of the electrospun membranes.Electrospun membranes in the collagen group(bone marrow mesenchymal stem cells were inoculated on the collagen surface to obtain the stem cell-engineered electrospun membranes),disordered fiber group and ordered fiber group were cocultured with bone marrow mesenchymal stem cells.The biocompatibility of electrospun membranes was evaluated using CCK-8 assay and live/dead staining.Integrin β1 immunofluorescence staining was used to evaluate the adhesion characteristics of electrospun membranes.The stem cell-engineered electrospun membrane and the electrospun membrane in the collagen group were cocultured with bone marrow macrophages respectively.Immunomodulatory properties were assessed by detecting the expression of inflammation-related genes using inducible nitric oxide synthase(M1 type),CD206(M2 type)immunofluorescence staining,and qRT-PCR. RESULTS AND CONCLUSION:(1)The oriented electrospun fiber membrane could mimic the structure of the longitudinally aligned natural dura mater,and the addition of collagen increased the hydrophilicity of the fiber membrane by about 2-fold and the mechanical properties by 1.2-fold.(2)When cocultured with bone marrow mesenchymal stem cells,CCK-8 assay and live/dead staining suggested that the cellular bioactivity in the collagen group was significantly higher than that in the disordered fiber group and ordered fiber group.Immunofluorescence staining revealed that the expression of integrin β1 in the collagen group was about 2.6 times higher than that of the disordered and ordered fiber groups,and the cell spreading morphology was good.(3)When cocultured with bone marrow macrophages,immunofluorescence staining exhibited that the fluorescence intensity of M1 type macrophages in the stem cell-engineered electrospun membrane group was lower than that in the collagen group(P<0.01),and the fluorescence intensity of M2 type macrophages was higher than that in the collagen group(P<0.01).qRT-PCR demonstrated that proinflammatory gene tumor necrosis factor α and interleukin-1β mRNA expression in the stem cell-engineered electrospun membrane group was lower than that of the collagen group(P<0.001);anti-inflammatory genes such as interleukin-10 and transforming growth factor β mRNA expressions were higher than those in the collagen group(P<0.001).(4)The above results suggest that the stem cell-engineered amphipathic artificial dura mimics the directional structure of normal dura,with the inner surface facilitating cell growth and adhesion and the outer edge avoiding tissue adhesion,while the polarization of macrophages to the M2 subtype is promoted and the local inflammatory microenvironment is regulated through the mesenchymal stem cell paracrine component.

Chondrogenic differentiation of rabbit bone marrow mesenchymal stem cells induced by growth differentiation factor 5 / 中国组织工程研究

BACKGROUND:Growth differentiation factor 5 is a member of the transforming growth factor superfamily and one of the earliest markers of joint development.Growth differentiation factor 5 has an important role in cartilage repair. OBJECTIVE:To explore the action mechanism of growth differentiation factor 5-induced chondrogenic differentiation of bone marrow mesenchymal stem cells. METHODS:Rabbit bone marrow mesenchymal stem cells were isolated and cultured.CCK-8 assay was used to detect the effect of different mass concentrations of growth differentiation factor 5 on the proliferation activity of bone marrow mesenchymal stem cells.RT-PCR was utilized to detect the expression of genes related to chondrogenic differentiation of bone marrow mesenchymal stem cells induced by different mass concentrations of growth differentiation factor 5.To further investigate the action mechanism of growth differentiation factor 5-induced chondrogenic differentiation of bone marrow mesenchymal stem cells,we added inhibitor XAV-939 and activator Laduviglusib of Wnt/β-catenin signaling pathways to induce cell culture for 14 days.RT-PCR and western blot assay were performed to detect the expression of cartilage-related genes and Wnt/β-catenin signaling pathway proteins. RESULTS AND CONCLUSION:(1)CCK-8 results showed no significant effect of growth differentiation factor 5 on the proliferation of bone marrow mesenchymal stem cells.(2)Growth differentiation factor 5 promoted the expression of cartilage-related genes type Ⅱ collagen,aggrecan and Sox9,among which growth differentiation factor 5 induced a significant upregulation of cartilage-related genes in the 50 ng/mL group.(3)Addition of Laduviglusib,an activator of Wnt/β-catenin signaling pathway,upregulated Sox9,β-catenin and type Ⅱ collagen expression(P<0.05).Addition of XAV939,an inhibitor of Wnt/β-catenin signaling pathway,down-regulated Sox9,β-catenin and type Ⅱ collagen expression(P<0.05).(4)Taken together,growth differentiation factor 5-induced chondrogenic differentiation of bone marrow mesenchymal stem cells may be associated with the activation of the Wnt/β-catenin signaling pathway.

Strontium-containing mesoporous bioactive glass nanoparticles loaded with bisphosphonates ameliorate bone loss in ovariectomized mice / 中国组织工程研究

BACKGROUND:Inhibition of osteoclast activity by bisphosphonates slows the progression of osteoporosis.However,serious complications of bisphosphonates,such as osteonecrosis of the jaw and atypical femur fracture,limit the clinical application of bisphosphonates.Effective alternative therapies need to be sought to improve existing clinical dilemmas. OBJECTIVE:To prepare strontium-containing mesoporous bioactive glass nanoparticles loaded with bisphosphonates(BPS@Sr-MBG)and analyze its activity against bone loss. METHODS:Strontium-containing mesoporous bioactive glass nanoparticles(Sr-MBG)were prepared by sol-gel method and added to alendronate saturated solution for the preparation of BPS@Sr-MBG.(1)Cell experiment:Mouse bone marrow macrophages were inoculated in 96-well plates and supplemented with ɑ-MEM complete culture medium containing macrophage colony stimulating factor and activator-ligand of nuclear factor κB receptor for osteoclast induced differentiation experiment.Meanwhile,they were cultured in three groups.The blank group was added with PBS.The control group was added with bisphosphonate,and the experimental group was added with BPS@Sr-MBG.After 5 days of culture,the differentiation of osteoclasts was observed by F-actin ring staining.(2)Animal experiments:Twenty-four female C57/BL mice were randomly divided into four groups with six mice in each group.Except sham operation group,ovariectomy group,BPS group and BPS@Sr-MBG group were used to construct osteoporosis model.One week after model establishment,mice in BPS group and BPS@Sr-MBG group were intraperitoneally injected with bisphosphonate solution and BPS@Sr-MBG solution,respectively.Mice in the sham operation group and ovariectomy group were intraperitoneally injected with PBS once a week.After 8 weeks of continuous injection,mouse femurs were taken for Micro-CT scanning and hematoxylin-eosin staining. RESULTS AND CONCLUSION:(1)Cell experiment:F-actin ring-formation staining demonstrated that compared with blank group,the area proportion and number of osteoclasts in the control group were decreased(P<0.01).Compared with the control group,the area proportion of osteoclasts and the number of osteoclasts in the experimental group were decreased(P<0.01).(2)Animal experiments:Micro-CT scanning results of femur showed that compared with the sham operation group,bone density,trabecular bone volume fraction,trabecular thickness and trabecular number of mice in the ovariectomy group were decreased(P<0.05,P<0.01),while trabecular distance and structural model index were increased(P<0.01).Compared with the ovariectomy group,the above bone parameters in the BPS group and BPS@Sr-MBG group were significantly improved(P<0.01),and the improvement in the BPS@Sr-MBG group was more obvious.The Micro-CT scanning results were further confirmed by hematoxylin-eosin staining of the femur.(3)The results show that BPS@Sr-MBG can exert anti-osteoporosis activity through anti-osteoclastic effect and promoting bone formation.