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Diabetic foot ulcers are common in elderly people with diabetes.Ongoing research is aimed at unraveling the complicated molecular mechanisms underlying diabetic foot ulcers.The role of cellular aging in delayed healing of diabetic foot ulcers has been recognized.Analyzing the relationship between cellular aging and diabetic foot ulcers, examining how cellular aging delays the healing of diabetic foot wounds, and identifying treatment methods for the removal of senescent cells and for slowing down cellular senescence will provide new therapeutic targets and strategies for the development of drugs for diabetic foot ulcers.
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Objective:To preliminarily investigate the effect of circIGF2BP3 on autophagy in photoaged dermal fibroblasts.Methods:Human dermal fibroblasts were isolated from circumcised foreskin tissues from 6 children in the Department of Urological Surgery, Third Affiliated Hospital of Sun Yat-sen University. An ultraviolet A (UVA) -induced photoaged human dermal fibroblast model (UVA radiation group) was established by repeated UVA radiation at a dose of 10 J/cm 2 for 14 consecutive days, and human dermal fibroblasts receiving no treatment served as control group. The photoaged cell model was verified by β-galactosidase staining, Western blot analysis for determining P21 protein expression, and cell counting kit-8 (CCK8) assay for evaluating cell viability. Moreover, Western blot analysis was performed to determine the protein expression of autophagy-related proteins P62, microtubule-associated protein 1 light chain 3 (LC3) -Ⅰand LC3-Ⅱ in photoaged human dermal fibroblasts, and real-time quantitative RCR (qRT-PCR) to verify the differential expression of circIGF2BP3 between photoaged and normal human dermal fibroblasts. Furthermore, circIGF2BP3 was biologically annotated. Some cultured primary human dermal fibroblasts were divided into 4 groups: empty vector group transfected with an empty vector, UVA + empty vector group transfected with an empty vector followed by repeated UVA radiation, circIGF2BP3 group transfected with a circIGF2BP3-overexpressing lentiviral vector, UVA + circIGF2BP3 group transfected with a circIGF2BP3-overexpressing lentiviral vector followed by repeated UVA radiation. Western blot analysis was performed to determine the expression of autophagy-related proteins. Statistical analysis was carried out by using t test, one-way analysis of variance and least significant difference- t test. Results:Compared with the control group, the UVA radiation group showed significantly increased proportions of β-galactosidase-positive cells (61.33% ± 5.78% vs. 6.37% ± 0.32%, t = 9.49, P < 0.01) and P21 expression (1.25 ± 0.03 vs. 1.00 ± 0.05, t = 4.26, P < 0.05), but significantly decreased cell viability (74.33% ± 3.48% vs. 100%, t = 7.38, P < 0.01). Moreover, the P62 expression and LC3-Ⅱ/Ⅰ ratio were significantly higher in the UVA radiation group than in the control group (both P < 0.05). The relative expression of circIGF2BP3 was 0.72 ± 0.04 in the photoaged human dermal fibroblasts, which was significantly lower than that in the normal human dermal fibroblasts (1.00 ± 0.03, t = 5.46, P < 0.01). The P62 expression and LC3-Ⅱ/Ⅰ ratio were significantly lower in the circIGF2BP3 group (0.60 ± 0.01, 0.71 ± 0.01, respectively) than in the empty vector group (1.00 ± 0.02, 1.00 ± 0.01, t = 16.25, 2.75, P < 0.01, < 0.05, respectively), and lower in the UVA + circIGF2BP3 group (1.05 ± 0.02, 2.04 ± 0.05, respectively) than in the UVA + empty vector group (1.31 ± 0.02, 2.72 ± 0.14, t = 10.493, 6.472, respectively, both P < 0.01) . Conclusion:circIGF2BP3 can regulate autophagy in UVA-induced photoaged dermal fibroblasts, which provides a new potential therapeutic target for the prevention and treatment of skin photoaging.
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Cysteine protease inhibitor SN (CST1) is one of the members of type 2 Cystatin superfamily. It is widely expressed and distributed in mammals. It contains many types of CST proteins and is located on chromosome 20p11.2. Cystatin SN has a variety of biological functions and is involved in the occurrence and development of tumor genesis and metastasis, inflammation, cell cycle and aging.
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Resumo Fundamento Doenças cardiovasculares (DCV) são uma das principais causas de mortalidade e morbidade em todo o mundo. O envelhecimento biológico tem sido associado à ocorrência de resultados cardiovasculares. Entretanto, o mecanismo subjacente desse processo ainda é desconhecido. Objetivos Buscamos avaliar se a senescência das células sanguíneas mononucleares periféricas (CSMP) e biomarcadores endoteliais poderiam influenciar o risco cardiovascular (CV) e ser marcadores adequados para a detecção precoce de doenças cardiovasculares em adultos. Métodos Neste estudo transversal, pacientes livres de DCV foram classificados como baixo (n=32) e alto (n=28) escore de risco intracardaco (IHR) A senescência das CSMP foi avaliada estimando-se a atividade de telomerase (AT) e detectando-se a presença de células senescentes e disfunção endotelial, estimando-se a concentração de nitrito e nitrato e a capacidade antioxidante total (CAT). A análise estatística foi realizada com o software SPSS, versão 16.0 (SPSS Inc., Chicago, IL). Todos os p-valores <0,05 foram considerados estatisticamente significativos. Resultados A senescência de CSMP de 0,95 [p-valor = 0,0001; 95% IC (0,874-1,026)] foi um indicador significativo de pacientes com escore de IHR mais alto, com um valor de corte de 21,65, com sensibilidade e especificidade de 92% e 88% respectivamente. Identificou-se que a senescência de CSMP, nitrito e nitrato, e AT eram independentemente associadas a um escore de IHR alto. Conclusão Os status de nitrito e nitrato e AT, e a senescência de CSMP são medidas adequadas para prever o alto risco cardiovascular em adultos com risco CV. Entretanto devem ser realizados estudos de acompanhamento de longo prazo para confirmar esses achados. (Arq Bras Cardiol. 2021; 116(1):37-47)
Abstract Background Cardiovascular diseases (CVD) are one of the leading causes of mortality and morbidity worldwide. Biological aging has been associated with the occurrence of adverse cardiovascular outcomes; however, the underlying mechanism of this process remains unknown. Objectives This study sought to evaluate if peripheral blood mononuclear cell (PBMC) senescence and endothelial biomarkers could influence cardiovascular (CV) risk and be suitable markers for the early detection of cardiovascular diseases in adults. Methods In this cross-sectional study patients free of CVD were classified as lower (n=32) and higher Interheart Risk (IHR) scores (n=28). PBMC senescence was assessed by estimating the telomerase activity (TA) and detecting the presence of senescent cells and endothelial dysfunction by estimating the concentration of nitrite and nitrate and of total antioxidant capacity (TAC). Statistical analysis was performed with SPSS version 16.0 (SPSS Inc., Chicago, IL). All p-values <0.05 were considered statistically significant. Results PBMC senescence 0.95 [p-value = 0.0001; 95% CI (0.874-1.026)] was a significant predictor of patients with higher IHR scores with a cut-off value of 21.65 with a sensitivity and specificity of 92% and 88% respectively. PBMC senescence, nitrite and nitrate and TA were found to be independently associated with high IHR scores. Conclusion PBMC senescence, TA and nitrite, and nitrate status are suitable measures to predict high cardiovascular risk in adults with CV risk. Nevertheless, long-term follow-up studies are needed to confirm these findings. (Arq Bras Cardiol. 2021; 116(1):37-47)
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Humans , Adult , Leukocytes, Mononuclear , Cardiovascular Diseases/diagnosis , Cross-Sectional Studies , Risk Factors , Heart Disease Risk FactorsABSTRACT
Objective:To investigate the expression of microRNA (miR) -26a in human skin fibroblasts during photoaging induced by ultraviolet A (UVA) , and to evaluate the effect of up-or down-regulation of miR-26a expression on the methylation level of the whole genome, the target gene enhancer of zeste homolog 2 (EZH2) and cell aging.Methods:Some human skin fibroblasts were irradiated with 10 J/cm 2 UVA once a day for 7 consecutive days, RNA was extracted on days 0, 3 and 7, and real-time quantitative reverse PCR (RT-PCR) was performed to determine the expression of miR-26a; miR-26a mimics and inhibitors were transfected into fibroblasts to up-or down-regulate the expression of miR-26a respectively, and fluorescence microscopy and RT-PCR were performed to determine the expression of miR-26a and evaluate the transfection efficiency. Some human skin fibroblasts were divided into 6 groups: blank control group receiving no treatment, UVA group treated with UVA irradiation according to the above method, miR-26a mimic group transfected with miR-26a-mimics, UVA+miR-26a mimic group transfected with miR-26a-mimics followed by UVA irradiation, miR-26a inhibitor group transfected with miR-26a inhibitors, UVA+miR-26a inhibitor group transfected with miR-26a inhibitors followed by UVA irradiation. On day 7, cells in each group were collected after the end of UVA irradiation. Then, flow cytometry was performed to detect cell cycle, DNA methylation quantitative detection kit was used to detect the methylation level of whole genome, RT-PCR was conducted to determine the mRNA expression of EZH2 (a histone-lysine N-methyltransferase enzyme) , DNA methyltransferase 1 (DNMT1) and miR-26a, and Western blot analysis was performed to determine the protein expression of EZH2 and DNMT1. Statistical analysis was carried out by using one-way analysis of variance and least significant difference- t test. Results:Compared with the unirradiated control group, the expression of miR-26a gradually increased in the UVA irradiation group over time during the culture, and there was a significant difference in the expression of miR-26a between the two groups after 7 days of UVA irradiation ( t=5.295, P < 0.05) . Strong fluorescence signals were observed in the miR-26a mimic-or miR-26a inhibitor-transfected fibroblasts, suggesting a high transfection efficiency. Flow cytometry showed that the proportion of cells at G1 phase significantly differed among the blank control group, UVA group, miR-26a mimic group, UVA+miR-26a mimic group, miR-26a inhibitor group, and UVA+miR-26a inhibitor group (52.82% ± 2.56%, 78.56% ± 4.34%, 53.63% ± 3.13%, 89.52% ± 4.17%, 54.39% ± 3.86%, 65.34% ± 4.78%, respectively; F=46.728, P < 0.01) , and significantly higher in the UVA group than in the blank control group ( t=8.848, P < 0.01) , higher in the UVA+miR-26a mimic group than in the miR-26a mimic group and UVA group ( t=11.922, 3.154, P < 0.01, < 0.05, respectively) , and higher in the UVA+miR-26a inhibitor group than in the miR-26a-inhibitor group ( t=3.087, P < 0.05) , but significantly lower in the UVA+miR-26a inhibitor group than in the UVA group ( t=3.547, P < 0.05) . Detection of the genome-wide methylation level showed that the methylation level ( A450 value) significantly differed among the above groups (0.676 ± 0.024, 0.323 ± 0.043, 0.506 ± 0.035, 0.169 ± 0.024, 0.602 ± 0.036, 0.422 ± 0.029, respectively, F=97.402, P < 0.01) , and significantly lower in the UVA group than in the blank control group ( P < 0.01) , lower in the UVA+miR-26a mimic group than in the miR-26a mimic group and UVA group (both P < 0.01) , and lower in the UVA+miR-26a inhibitor group than in the miR-26a inhibitor group ( P < 0.01) , but significantly higher in the UVA+miR-26a inhibitor group than in the UVA group ( P < 0.05) . RT-PCR and Western blot analysis showed significant differences in the mRNA and protein expression of EZH2 and DNMT1 respectively among the 6 groups (both P < 0.05) , which were significantly lower in the UVA group than in the blank control group ( P < 0.05) , lower in the UVA+miR-26a mimic group than in the miR-26a mimic group and UVA group (both P < 0.05) , and lower in the UVA+miR-26a inhibitor group than in the miR-26a inhibitor group ( P < 0.05) , but significantly higher in the UVA+miR-26a inhibitor group than in the UVA group ( P < 0.05) . Conclusion:In the UVA irradiation-induced photoaging of skin fibroblasts, miR-26a expression was up-regulated, cellular proliferative activity and genome-wide methylation level decreased; up-regulation of miR-26a expression could down-regulate the expression of its target gene EZH2 and methylation-related gene DNM1, and promote cell photoaging, while down-regulation of miR-26a expression could up-regulate the expression of EZH2 and DNMT1, and inhibit cell photoaging.
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Objective:To compare aging models for renal tubular epithelial cells induced by different drugs.Methods:Different concentrations of D-galactose(D-gal), hydrogen peroxide(H 2O 2)and cisplatin(CDDP)were administered to the human proximal tubular epithelial cell line(HK2). Cell activity and the half maximal inhibitory concentration(IC50)were measured by the CCK-8 assay; cell senescence was assessed by senescence-related β-galactosidase staining(SA-β-gal); senescence-related gene expression was detected by Western blotting; cell cycle distribution and apoptosis were determined by flow cytometry.Pathological changes in renal tubules and interstitial tissues were examined in D-gal-induced and naturally aging mice using HE staining, and p16 expression was detected using immunohistochemistry. Results:CCK-8 assay results showed that HK2 cell activity was inhibited treatment with each of the three compounds.The 48-hour IC50 values were(365.8±9.7)mmol/L for D-gal, (385.4±20.8)μmol/L for H 2O 2 and(8.4±1.6)μmol/L for CDDP.Light microscopic observation revealed slowed growth of HK2 cells in the three groups.The rate of SA-β-gal-positive cells increased, compared with the control group( P<0.05). Treatment resulted in an increase in G0/G1 phase cells by(22.9±1.0)% in the 400 mmol/L D-gal group and by(13.0±4.4)% in the 400 μmol/L H 2O 2 group, while G2/M phase cells increased by(14.4±1.9)%( t=48.07, 6.40, 16.53, P<0.05)in the 8 μmol/L CDDP group, compared with the control group.Also, compared with the control group, HK2 cell apoptosis increased by(50.3±1.0)% in the 400 μmol/L H 2O 2 group and by(41.9±2.0)% in the 8 μmol/L CDDP group, which was significantly higher than(7.7±0.4)% in the 400 mmol/L D-gal group( t=77.47, 33.73, 28.35, all P<0.05). Western blotting results indicated that the expression of CCND1 was down-regulated after any of the three drugs reached a certain concentration.The expression of p16 in the D-gal group was up-regulated( F=92.88, P<0.05), but there was no statistical difference in the expression of p16 after H 2O 2 or CDDP treatment.Mice of the D-gal model showed a decline in renal tubular cells, thickened basement membrane, widened interstitial spaces and increased expression of p16 in renal tubules similar to those observed in naturally aging mice. Conclusions:For HK2 cell senescence models induced by three different drugs, the renal tubular epithelial cell senescence model induced by D-gal is relatively close to the natural senescence model.
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@#<p>Glaucoma is a common irreversible blinding eye disease, pathological elevated intraocular pressure is the main clinical feature. The formation of intraocular pressure, related to aqueous circulation, will be pathologically elevated when the aqueous cycle is abnormal. Trabecular network, which plays a key role in maintaining normal intraocular pressure, is the main component of aqueous outflow channel. Imbalance of oxidative stress manifested as oxidation and antioxidant effects is a direct risk factor for elevated intraocular pressure in glaucoma. When it comes to the trabecular meshwork cells, a series of changes such as deposition and degeneration of extracellular matrix, autophagy and aging will eventually occur, and finally the dysfunction of trabecular meshwork cells and increased aqueous outflow resistance, causing intraocular pressure pathological elevated. In this paper, we reviewed the research progress on the relationship between oxidative stress in trabecular meshwork cells and the pathogenesis of glaucoma, in order to provide evidence for further research and reference for exploring the pathogenesis, prevention and treatment of glaucoma.
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@#AIM: To observe the effects of Qi Jing Mingmu decoction combined with artificial tears on the clinical results and cell aging of conjunctivochalasis. <p>METHODS: Forty cases(80 eyes)of grade II-Ⅳ CCH with liver-kidney Yin deficiency were randomly divided into two groups: combined treatment group and artificial tears group, which were treated with Qi Jing Mingmu decoction combined with artificial tears and simple artificial tears respectively. The international ocular surface disease index(OSDI), tear break-up time(BUT)and Schirmer Ⅰ test(SⅠt)were observed and the clinical effects were compared after 3mo treatment. For CCH patients with grade III or above, followed up for 3mo or more and willing to operate, the loose conjunctival tissue was removed and the cell aging related β-gal staining was performed on frozen sections. The results were statistically analyzed. <p>RESULTS: The OSDI score(14.53±2.68), BUT 9.25±3.02s and SⅠt(8.95±3.57mm/5min)of combined treatment group were significantly better than those of artificial tears group after 3mo treatment(all <i>P</i><0.05). After drug treatment, 7 cases(7 eyes)in artificial tears group and 4 cases(4 eyes)in combined treatment group of CCH patients were treated by operation. The positive rate of aging cells in combined treatment group was significantly lower than that in artificial tears group(16.00±7.84 <i>vs </i>39.00±14.09, <i>P</i>=0.013).<p>CONCLUSION: Qi Jing Mingmu decoction combined with artificial tears to treat CCH is more effective than simple artificial tears in relieving ocular symptoms, improving tear film and promoting tear secretion. Combined treatment can also reduce the cell aging in CCH, which can be used as a safe and effective treatment method in addition to surgical operation.
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@#AIM: To observe the effects of Qi Jing Mingmu decoction combined with artificial tears on the clinical results and cell aging of conjunctivochalasis. <p>METHODS: Forty cases(80 eyes)of grade II-Ⅳ CCH with liver-kidney Yin deficiency were randomly divided into two groups: combined treatment group and artificial tears group, which were treated with Qi Jing Mingmu decoction combined with artificial tears and simple artificial tears respectively. The international ocular surface disease index(OSDI), tear break-up time(BUT)and Schirmer Ⅰ test(SⅠt)were observed and the clinical effects were compared after 3mo treatment. For CCH patients with grade III or above, followed up for 3mo or more and willing to operate, the loose conjunctival tissue was removed and the cell aging related β-gal staining was performed on frozen sections. The results were statistically analyzed. <p>RESULTS: The OSDI score(14.53±2.68), BUT 9.25±3.02s and SⅠt(8.95±3.57mm/5min)of combined treatment group were significantly better than those of artificial tears group after 3mo treatment(all <i>P</i><0.05). After drug treatment, 7 cases(7 eyes)in artificial tears group and 4 cases(4 eyes)in combined treatment group of CCH patients were treated by operation. The positive rate of aging cells in combined treatment group was significantly lower than that in artificial tears group(16.00±7.84 <i>vs </i>39.00±14.09, <i>P</i>=0.013).<p>CONCLUSION: Qi Jing Mingmu decoction combined with artificial tears to treat CCH is more effective than simple artificial tears in relieving ocular symptoms, improving tear film and promoting tear secretion. Combined treatment can also reduce the cell aging in CCH, which can be used as a safe and effective treatment method in addition to surgical operation.
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Objective@#To study the alterations of mitochondrial biological characteristics during both cellular replicative and premature senescence induced by hydrogen peroxide in human embryonic lung fibroblasts (HEFs).@*Methods@#The premature senescence was induced by 400 μmol/L H2O2 once a day at the same time and with 2 hours each time, after four consecutive days the premature senescence models were classified into premature senescence initiation group (PSi) and premature senescence persistence group (PSp). Based on the life span of HEFs, the cell replicative senescence was divided into five groups included young-age (22 PDL), middle-age (35 PDL), replicative senescence (49 PDL), PSi and PSp. The mitochondrial distribution, relative content, adenosine triphosphate (ATP) contents, 8-hydroxydeoxyguanosine (8-OHdG) levels, the relative mitochondrial transcription factor A (TFAM) as well as mitochondrial DNA methyltransferase 1 (mtDNMT1) mRNA levels, mtDNA copy number, the relative TFAM protein level and the total enzyme activity of mitochondrial DNA methyltransferases (mtDNMTs) were detected in five senescence groups.@*Results@#The mtDNA copy number, 8-OHdG contents, level of mtDNMT1 mRNA and mtDNMTs activity in 49 PDL group were higher than those in 22 PDL group (all P values <0.05); The level of 8-OHdG in PSi was higher than that in 22 PDL group (P<0.05); The ATP contents, mtDNA copy number, the mRNA and protein expression levels of TFAM and mtDNMTs activity of PSp were higher than those in 22 PDL group (all P values<0.05).@*Conclusion@#During the cellular senescence of HEFs, the higher mtDNA copy number and mtDNMTs activity were common features regardless of replicative or premature senescence, with possibility that oxidative stress was involved in modifying the occurrence of premature senescence.
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Aging is age-related degeneration of the whole body,and skin aging is one of the most visualized changes in aging.Cellular senescence is a stress response to stable cell cycle arrest,and it is both the hallmark of aging and the important mechanism of the occurrence and development of aging.With the development of skin aging,senescent cells gradually accumulate in both the epidermis and dennis,and further exacerbate aging.Thus,when these senescent cells are eliminated,the aging skin seems to be rejuvenated.Cellular senescence is involved in the process of skin aging,which may be related to activation of DNA damage response pathway,up-regulation of regulatory proteins blocking cell cycle,and increase of senescence-associated secretory phenotypes.Cellular senescence is expected to be a novel target for preventing skin aging in the future.
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Fibrosis as a pathogenic mechanism occurs in numerous organs and diseases.Persistent and severe fibrosis affect the function of the organ.Organ fibrosis is an important cause of patient morbidity and mortality.Aging is considered as a strong risk factor for development of organ fibrosis.Organ fibrosis is age-related disease and cellular senescence plays an important role in the occurrence and development of fibrosis,which provides a new strategy for the treatment of fibrosis.This review is focused on the progress in cellular senescence and organ fibrosis.
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Objective: To explore the molecular mechanism of Jinfukang inducing the senescence of circulating tumor cells (CTCs) in patients with non-small cell lung cancer. Methods: Human lung cancer CTCs (CTC-TJH-01 cells) were treated with different concentrations (0, 125, 250, 500 and 1 000 μg/mL) of Jinfukang. The proliferation of CTC-TJH-01 cells was detected by CCK-8 assay. The state of cellular senescence was detected by β-galactosidase staining. The expression of proliferating cell nuclear antigen (PCNA) protein in CTC-TJH-01 cells was detected by flow cytometry and immunofluorescence staining. The expression levels of proliferation- and senescence-associated proteins including p16, p21, retinoblastoma protein (RB) and phospho-RB (p-RB) were detected by Western blotting. Results: Jinfukang inhibited the proliferation of CTC-TJH-01 cells (500 and 1 000 μg/mL: both P < 0.05), induced the senescence of CTC-TJH-01 cells (350 and 700 μg/mL: both P < 0.05), and promoted the expression of PCNA protein in CTC-TJH-01 cells (350 and 700 μg/mL: both P < 0.05). The expression levels of p16 and p21 proteins were up-regulated, but the expression level of p-RB protein was down-regulated after treatment (all P < 0.05). Conclusion: Jinfukang induces the senescence of CTCs by regulating p16/RB signal pathway, which may be the mechanism of preventing the recurrence and metastasis of lung cancer.
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Objective To investigate the mechanism of cellular senescence in ischemia reperfusion injury (IRI)-induced acute kidney injury (AKI) that leads to chronic kidney disease (CKD) in elderly mice.Methods An acute kidney injury model was established in C57B1/6 male mice at ages 8-10 weeks (young group) or 20-24 months (old group) by bilateral IRI.The animals were randomly divided into 4 groups as follows:Young-Sham (n=8),Old-Sham (n=8),Young-IRI (n=8),and Old-IRI groups (n=8).All mice were weighted,and their blood was collected from the tail vein at days 1,3,and 7 after surgery.The mice were killed on day 14 after surgery,and their kidneys were harvested for further analysis.Serum was used for the creatinine test.The changes of the renal tissue morphology and pathology were assessed using hematoxylin-eosin staining and sirius red staining.Immunofluorescence staining of collagen Ⅰ,F4/80,phosphor-histone H3 (p-HH3),and Ki67 were performed to determine the stage of the collagen deposit,macrophage filtration,and cell cycle G2/M arrest.The collagen Ⅰ expression was analyzed using western blot.The expression levels of TNF-α,IL-6,TGF-β,and collagen Ⅰ were determined using real-time PCR.Results Compared with that in the sham group,the serum creatinine levels in both Young-IRI and Old-IR1 groups were obviously increased.The Young-IRI group recovered completely on day 7.The Old-IRI group had higher creatinine levels than the Young-IRI group at each time point.Morphology and pathology analyses revealed that acute injury was repaired in the Young-IRI group,but slight inflammatory cell filtration and collagen deposition were observed in the Old-Sham and Old-IRI groups,respectively.Immunofluorescence staining revealed some F4/80-positive macrophage filtration,collagen Ⅰ deposition,and p-HH3 and Ki67 double-positive nuclear tubular epithelial cells in the Old-Sham group,but considerably more positive results were found in the Old-IRI group.Western blot analysis revealed that collagen Ⅰ expression level was higher in the Old-IRI group than in the Young-IRI group (P ＜ 0.01) and in the Old-Sham group than in the Young-Sham group (P ＜ 0.05).Real-time PCR demonstrated that the mRNA expression levels of cytokines and fibrosis markers,including of TNF-α,IL-6,TGF-β,and collagen Ⅰ,in the Old-Sham and Old-IRI groups were increased as compared with those in the Young-Sham and Young-IRI groups (P ＜ 0.05).Conclusions The levels of kidney inflammation,fibrosis,and cell-cycle arrest are lower in the old mice.After IRI injury,a sustained and ongoing inflammatory reaction is involved and more cells are arrested in the cell cycle G2/M,which inhibit renal repair and promote fibrosis progression.
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Objective To evaluate the effect of photoaging on the degradation of advanced glycation end products (AGEs) by human dermal fibroblasts.Methods Some cultured human dermal fibroblasts were subjected to repetitive ultraviolet A (UVA) radiation (UVA radiation group) to establish a photoaging cell model,which was then evaluated by cell counting kit 8 (CCK-8) assay,senescenceassociated β-galactosidase staining and detection of apoptosis rate.Moreover,fibroblasts receiving no treatment served as control group.Some other primary fibroblasts were divided into 4 groups:photoaged group receiving UVA radiation,non-photoaged group receiving no treatment,AGE-treated photoaged group treated with UVA radiation followed by the treatment with 200 mg/L AGE-bovine serum albumin (BSA),and AGE-treated non-photoaged group treated with 200 mg/L AGE-BSA alone.After the treatment with AGE-BSA for 4-72 hours,flow cytometry was performed to determine the fluorescence intensity of AGE-BSA in fibroblasts of the above groups.After 8-hour treatment with AGE-BSA,confocal laser scanning microscopy was performed to localize and semiquantitatively detect AGE-BSA in fibroblasts,and enzymelinked immunosorbent assay (ELISA) was conducted to detect AGE-BSA levels in fibroblasts,as well as changes in the intracellular AGE-BSA level within 24 hours after the removal of AGE-BSA.Results Compared with the control group,the UVA radiation group showed significantly decreased cellular proliferative activity (t =7.559,P ＜ 0.05),but significantly increased apoptosis rate and percentage of β-galactosidase-positive fibroblasts (t =14.075,43.524 respectively,both P ＜ 0.05).Flow cytometry revealed that the average fluorescence intensities of AGE-BSA after 4-,8-,16-,24-,48-and 72-hour treatment with AGE-BSA were significantly higher in the AGE-treated photoaged group (293.00 ± 8.19,359.67 ± 11.59,347.00 ± 12.29,338.00 ± 12.77,334.67 ± 14.22 and 336.30 ± 10.21,respectively) than in the photoaged group (all P ＜ 0.05),as well as in the AGE-treated non-photoaged group (222.33 ± 8.74,276.33 ± 6.11,256.33 ± 5.51,243.00 ± 10.15,236.33 ± 1.53 and 240.33 ± 1.52,respectively) than in the non-photoaged group (all P ＜ 0.05).Moreover,the average fluorescence intensities of AGE-BSA at different time points were all significantly higher in the AGE-treated photoaged group than in the AGE-treated non-photoaged group (all P ＜ 0.05).Confocal laser scanning microscopy showed that AGE-BSA was mainly localized in lysosomes after endocytic uptake into the fibroblasts,and the AGE-treated photoaged group showed significantly increased fluorescence intensity of AGE-BSA compared with the AGE-treated non-photoaged group (P ＜ 0.05).ELISA revealed that the intracellular AGE level in the AGE-treated non-photoaged group at 24 hours after the removal of AGE-BSA was decreased by (14.6 ± 1.2)％ compared with that before the removal,and the degradation rate of AGE-BSA was significantly higher in the AGE-treated non-photoaged group than in the AGE-treated photoaged group (7.6％ ± 1.4％,t =6.604,P ＜ 0.05).Conclusion The internalized AGE-degradating ability decreases in photoaged fibroblasts,which may induce the accumulation of AGEs in photoaged skin.
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Objectives To investigate the effects of cell aging on the disorders relating to gastric mucosa aging.Methods A treatment of 200 μmol/L H2O2 was used to induce senescence of human gastric epithelial cell line GES-1,and the cell growth curve was monitored.Senescence secretory phenotypes were observed by detecting the protein level of p53 and p16INK4a with senescence-associated β-galactosidase(SA-β gal)staining and Western blot testing.The mRNA levels of senescence-associated secretory phenotype(SASP)factors in human gastric epithelial GES-1 cell including IL-1β,IL-6,IL-8,TGF-β、IFN-γ,and VEGF-A were detected by RT PCR.The mRNA expression levels of IL-1β,IL-6,IL-8,TGF-β,IFN-γ,and VEGF in the conditioned medium were detected by ELISA analysis.Results The 200 μmol/L H2O2-induced GES-1 cells stopped proliferating after 3 days of treatment,and cells enlarged and flattened at 10 days.The increased SA-β-gal staining(P＜0.001) and the increased expression levels of p53 and p16INK4a proteins indicated the success of establishing the aging model of GES-1.The mRNA levels of IL 1β,IL6,IL8,TGF-β,and IFNγ were higher(t=2.94,3.38,3.15,3.64,2.97;P=0.015,0.000,0.000,0.000,0.000)and the mRNA level of VEGF-A was lower(t=2.31,P =0.20) in senescent GES-1 cells than in the control group.In the conditioned medium of senescent GES-1 cells,the levels of IL-1β,IL6,IL8,TGF-β1,and IFNγ were higher in the H2O2-induced group [(3.12±0.21)μg/L,(4.26±0.15)μg/L,(3.37±0.14)μg/L,(5.34±0.19)μg/L,and(2.90±0.47)μg/L]than in the negative control group[(0.24±0.04,0.04±0.07,0.52±0.02,1.05±0.10,0.52±0.02,respectively,P＜0.001)],while the level of VEGF was lower in the H2O2-induced group than in the negative control group(0.21±0.03)μg/L vs (0.59±0.07)μg/L(P＜0.05).Conclusions The changes in senescence-associated secretory phenotype factors of the aging human gastric epithelial cells induced by oxidative stress may promote chronic gastritis and gastric cancer.
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Vascular aging may influence the initiation,procession,and severity of various cardiovascular diseases,and thus is one of the most important risk factors for the high mortality of cardiovascular diseases.Vascular endothelial cells are the main cell biological basis of the vasculature,so the structure and function of vascular endothelial cells play a key role in vascular aging.Recently,the association between microRNAs and aging-related diseases has been studied.In this review,we will summarize the role of microRNAs in the process of endothelial cell aging.In addition,we will also discuss possible clinical applications of microRNAs as a diagnostic and therapeutic tool for vascular diseases.
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Objectives: To explore the modulating effects and related mechanisms of p53-miR-34a-SIRT1 feedback loop in the process of replication senescence of vascular endothelial progenitor cells (EPC). Methods: EPC derived from umbilical cord blood were cultured and identified. Differences on senescence, cell apoptosis, cell cycle and blood tube formation were observed in EPC of 3rdand 6thgeneration. Protein expression of p53, Acetyl-p53, and SIRT1 was also detected by Western blotting in EPC of 3rdand 6thgeneration. The miR-34a inhibitor lentiviral vector was constructed and used to identify whether miR-34a inhibitor can protect 6thgeneration EPC from apoptosis. Results: EPC derived from umbilical cord blood were successfully cultured. The cells senescence rate and apoptosis rate of the 6thgeneration EPC were significantly higher than those of the 3rdgeneration EPC. The cell cycle of 6thgeneration EPC was mainly arrested at G0/G1 phase. The protein expression level of p53 was significantly higher, while the protein expression of acetyl-p53 and SIRT1 was significantly lower in the 6thgeneration EPC than in the 3rdgeneration EPC, all P<0.05. The senescence was significantly attenuated, and late apoptotic cells were significantly reduced, while angiogenesis ability was significantly enhanced in the 6thgeneration EPC transfected with lentiviral vector carrying miR-34a inhibitor. Conclusions: p53-miR-34a-SIRT1 is an important feedback mechanism in the process of EPC replication senescence. The miR-34a inhibitor may be the potential target of delaying EPC senescence.
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Cell senescence is a basic cell response triggered by various stimuli and is a basic characteristic of living organism. Liver fibrosis refers to the pathological process of diffuse excessive deposition of extracellular matrix in the liver caused by abnormal proliferation of connec-tive tissue due to various pathogenic factors and can progress to liver cirrhosis and liver cancer. Studies have shown that cell senescence is closely associated with the progression of liver fibrosis. This article reviews the regulatory effect of different types of cell senescence on liver fibrosis.
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Objective To observe the effect of platelet-rich plasma (PRP) on photoaging skin of rat.Methods F344 rats were used as model animals and skin photoaging model was established by UV irradiation.The model animals were divided into 5 groups:group A was injected with activated PRP (A-PRP);group B was injected with inactive PRP (N-PRP);group C was injected with normal saline;group D was irradiated only with UV;Four weeks after the injection,the appearance and histological characteristics of the rat's skin were evaluated.Results Compared with group C and group D,the wrinkles and skin color in group A and group B were significantly improved.Histological observation showed that the histological features of group A and group B were significantly better than that of group C and D (P＜0.01).The thickness of dermis in group A was higher than that in group B (P＜0.05).There was no significant difference between groups C and D (P＞0.05).The thickness of dermis in group E was significantly higher than that in group C (P＜0.01).Conclusions Injection of PRP can improve the appearance and histological features of photo-aged skin in rats.A-PRP is better than N-PRP.