Effects of hypoxia-inducible factors on tumor mesenchymal cells: a review / 预防医学

@#Hypoxia is the most common tumor microenvironment caused by rapid proliferation of tumor cells, and hypoxia-inducible factor (HIF) is the main transcription factor for tumor cells to adapt to hypoxia. Current research has found that HIF can interact with a variety of mesenchymal cells such as fibroblasts, endothelial cells and immune cells in the tumor microenvironment, leading to the transcription and expression of target genes in response to hypoxia, which ultimately promotes tumor angiogenesis, and induces physiological changes such as migration, invasion, and immune escape of tumor cells. However, the signaling pathways involved in the HIF regulatory mechanism are complex, and the mechanism of HIF in the tumor microenvironment need to be further investigated, also most HIF inhibitors are still in the preclinical research stage. This paper reviews the research progress on the effects of HIF on tumor mesenchymal stromal cells to provide a theoretical basis for the diagnosis, prevention and treatment of tumors targeting HIF.

Correlation Between Expression of HIF-1α and Prognosis of Arsenic-containing Chinese Herbal Compound in Treatment of Myelodysplastic Syndrome / 中国实验方剂学杂志

ObjectiveMyelodysplastic syndromes （MDS） is a group of clonal hematopoietic stem cell disorders，and this study aims to investigate the expression of hypoxia-inducible factor-1α（HIF-1α） in the bone marrow cells of patients with MDS and its correlation with the clinical features of MDS，the therapeutic efficacy of arsenic-containing Chineseherbal compound，and the survival prognosis. MethodAccording to the inclusion and exclusion criteria，27 MDS patients treated with arsenic-containing Chinese herbal compound in the Department of Hematology，Xiyuan Hospital，China Academy of Chinese Medical Sciences from January 2022 to September 2022 were included，and their bone marrow samples were collected by myelotomy. HIF-1α expression level in bone marrow cells was detected by real-time polymerase chain reaction （PCR） to analyze its correlation with clinical features，and logistic and Cox regression was used to analyze the risk factors affecting the efficacy and prognostic survival of MDS patients. ResultThe HIF-1α mRNA expression level was lower in bone marrow cells of MDS patients than in healthy subjects. HIF-1α was positively correlated with the degree of myelodysplasia（r=0.384，P<0.05） and bone marrow granulocytic system%（G%）（r=0.560，P<0.01）. Logistic regression showed that HIF-1α was a risk factor for the prognosis in the follow-up of the efficacy of treatment（P<0.05）and Cox regression showed that HIF-1α was an independent factor affecting the survival prognosis of MDS patients ［odds ratio（OR）=398.968，95% confidence interval（CI）（1.281，116 858.743），P<0.05］. ConclusionThe level of HIF-1α expression in bone marrow cells of MDS patients was closely related to the degree of clinical myelodysplasia and G%，and HIF-1α was a risk factor for the efficacy for and survival prognosis of MDS patients.

Inhibition of Pannus Formation by Wutoutang in AIA Rats with Wind-cold-dampness Bi Syndrome Via Down-regulating HIF-1α/VEGFA/Ang Signaling Pathway / 中国实验方剂学杂志

ObjectiveThis study aims to investigate the inhibitory effect of Wutoutang on pannus formation in adjuvant-induced arthritis （AIA） rats with wind-cold-dampness Bi syndrome and its potential mechanism. MethodA total of 40 male SD specific pathogen-free （SPF） rats were selected and divided into blank group， wind-cold-dampness Bi syndrome group ［Complete Freund's Adjuvant （CFA）， 200 μg］， Wutoutang group （15 g·kg-1·d-1）， and indometacin group （10 mg·kg-1） according to random number table method. Except for the blank group， the other groups were given wind-cold-dampness stimulation before the CFA injection. After the rats were administered for 30 days， the basic conditions， onset time， arthritis index score， and foot swelling volume of AIA rats with wind-cold-dampness Bi syndrome were observed. Finally， peripheral arterial blood， ankle joint， and synovial tissue were taken. Enzyme-linked immunosorbent assay （ELISA） was used to detect serum hypoxia-inducible factor-1α （HIF-1α）， vascular endothelial growth factor A （VEGFA） protein content， and rheumatism， including anti-O （ASO）， C-reactive protein （CRP）， and rheumatoid factor （RF）. Hematoxylin-eosin （HE） staining revealed the changes in joint histomorphology. Immunohistochemistry was used to detect the expression of HIF-1α and VEGFA， two important proteins in the ankle pathway. Quantitative real-time polymerase chain reaction （Real-time PCR） was used to reveal mRNA levels of HIF-1α， VEGFA， angiopoietin-1 （Ang-1）， and angiopoietin-2 （Ang-2） in rat synovial tissue. ResultThe foot swelling volume and arthritis score of AIA rats with wind-cold-dampness Bi syndrome were substantially higher （P<0.01） compared with the blank group. Serum CRP， RF， and ASO levels were considerably elevated （P<0.01）. HE staining showed obvious hyperplasia of ankle synovium and synovial inflammation， angiogenesis and pannus formation， and aggravated bone destruction， indicating successful modeling. After the intervention of Wutoutang， the onset time was delayed （P<0.01）. Foot swelling volume and arthritis score were decreased （P<0.01）. Serum CRP， RF， and ASO levels were significantly decreased （P<0.01）. The inflammatory hyperplasia of synovial tissue， angiogenesis and pannus formation， and bone destruction were alleviated. The mRNA levels of HIF-1α， VEGFA， Ang-1， and Ang-2 in the synovial membrane were significantly decreased （P<0.05， P<0.01）. The expressions of HIF-1α and VEGFA in serum and ankle joints were decreased （P<0.01）. In the indomethacin group， the onset time of the disease was delayed （P<0.01）. Foot swelling volume and arthritis score were decreased （P<0.01）. Serum CRP， RF， and ASO levels were significantly decreased （P<0.01）. HIF-1α/VEGFA/Ang signaling pathway was activated， and pathological tissue injury was improved. ConclusionWutoutang can delay the onset time of AIA rats with wind-cold-dampness Bi syndrome， reduce foot swelling volume， arthritis score， rheumatic activity， and improve joint histopathology. It can inhibit pannus formation， and its mechanism may be related to down-regulating the expression of the HIF-1α/VEGFA/Ang pathway.

Mechanism of Shugan Huazheng Prescription Against Liver Fibrosis Based on HIF-1α/VEGF/TGF-β1 Pathway / 中国实验方剂学杂志

ObjectiveTo observe the therapeutic effect of Shugan Huazheng prescription on hepatic fibrosis model rats induced by carbon tetrachloride （CCl4） and explore whether it plays its role through hypoxia-induced factor-1α/vascular endothelial growth factor/transforming growth factor-β1 （HIF-1α/VEGF/TGF-β1） pathway. MethodA total of 54 male SPF SD rats were randomly divided into six groups： blank group， model group， colchicine group （0.2 mg·kg-1）， and high-， medium-， and low-dose groups （29.52， 14.76， and 7.38 g·kg-1） of Shugan Huazheng prescription， with nine rats in each group. The molding was conducted three times a week for eight weeks. Administration began the day after the first injection， and the drug intervention was once a day for eight weeks. On the day after the last administration， the rats were deprived of food and water， and they were killed the next day， during which the physiological status of each group of rats was dynamically monitored. The pathological changes in the liver were observed by hematoxylin-eosin （HE） staining， and the content of hydroxyproline （HYP） and angiotensin Ⅱ （AngⅡ） in liver tissue were detected by enzyme-related immunosorbent assay （ELISA）. Real-time fluorescent quantitative PCR （Real-time PCR） was used to determine the mRNA expression levels of HIF-1α， VEGF， and TGF-β1 in liver tissue， and immunohistochemical method （IHC） and Western blot were used to detect the protein expression levels of HIF-1α， VEGF， and TGF-β1 in liver tissue. ResultCompared with the blank group， the overall condition of rats in the model group decreased significantly. The proliferation of connective tissue and the increase in adipose cells between hepatocytes were obvious. The content of HYP and Ang was increased. The mRNA and protein expressions of HIF-1α， VEGF， and TGF-β1 were increased to varying degrees （P<0.05）. Compared with the model group， the proliferation of connective tissue and inflammatory cell infiltration in the liver tissue of colchicine and Shugan Huazheng prescription groups were reduced. The content of HYP and Ang was decreased. The mRNA and protein expression levels of HIF-1α， VEGF， and TGF-β1 were decreased， and the colchicine group and high-dose group of Shugan Huazheng prescription were the most significant （P<0.05）. ConclusionShugan Huazheng prescription has an obvious therapeutic effect on CCl4-induced hepatic fibrosis model rats. Its therapeutic mechanism may be related to the regulation of the HIF-1α/VEGF/TGF-β1 signaling pathway and the improvement of hepatic hypoxia， vascular remodeling， and the syndrome of Qi deficiency and blood stasis in hepatic fibrosis.

Huanglian Jiedutang Regulates HIF-1α/VEGF Signaling Pathway to Improve Learning and Memory Abilities of APP/PS1 Transgenic Mice / 中国实验方剂学杂志

ObjectiveTo reveal the effects of Huanglian Jiedutang （HLJDT） on the learning and memory abilities of APP/PS1 transgenic mice via hypoxia-inducible factor-1α （HIF-1α）/vascular endothelial growth factor （VEGF） signaling pathway. MethodForty 5-month-old β-amyloid precursor protein （APP）/presenilin 1（PS1） mice were randomized into the model， donepezil （0.001 g·kg-1·d-1）， and low-， medium-， and high-dose （1.5， 3， 6 g·kg-1·d-1， respectively） HLJDT groups， and 8 C57BL/6 mice were taken as the normal group. After 45 days of continuous administration， Morris water maze test was conducted， and the organ indexes were calculated. The morphological structure of cerebral vascular endothelial cells in mice was observed under a transmission electron microscope. Western blot was employed to measure the protein levels of APP， HIF-1α， VEGF，VEGFA， and brain-derived neurotrophic factor （BDNF） in the hippocampus. The mRNA levels of APP， HIF-1α， and VEGF were determined by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. ResultCompared with the normal group， the model group showed prolonged escape latency （P<0.05）， reduced distance and time around the target platform （P<0.05）， decrease brain and spleen indexes （P<0.05）， vascular endothelial cells with karyopyknosis and not abundant cytoplasm， up-regulated protein levels of APP， HIF-1α， VEGF， and VEGFA （P<0.05）， down-regulated protein level of BDNF （P<0.05）， and up-regulated mRNA levels of APP， HIF-1α， and VEGF （P<0.05） in the hippocampus. Compared with the model group， high-dose HLJDT shortened the escape latency （P<0.05）， increased the distance and time around the target platform （P<0.05）， raised the brain and spleen indexes （P<0.05）， repaired the organelles of vascular endothelial cells， down-regulated the protein levels of APP， HIF-1α， VEGF， and VEGFA （P<0.05）， up-regulated the protein level of BDNF （P<0.05）， and down-regulated the mRNA levels of APP， HIF-1α， and VEGF （P<0.05） in the hippocampus. ConclusionHLJDT can improve the learning and memory abilities of mice by reducing the expression of HIF-1α and VEGF， thus protecting the nerves.

Effect of lncRNA HIF1A-AS1 on chemotherapy sensitivity of vincristine-resistant in retinoblastoma cells / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the effect of long non-coding RNA-HIF1A-AS1(lncRNA HIF1A-AS1)on the chemotherapy sensitivity of vincristine(VCR)-resistant in retinoblastoma(RB)cells by regulating the expression of hypoxia-inducible factor-1α(HIF-1α).METHODS: The human RB VCR-resistant cell line SO-RB50/VCR was established, expression of lncRNA HIF1A-AS1 in SO-RB50 and SO-RB50/VCR cells were detected by reverse transcription-quantitative real-time PCR(RT-qPCR); inhibition of lncRNA HIF1A-AS1 expression or simultaneous overexpression of HIF-1α in SO-RB50/VCR cells, and then median inhibitory concentration(IC50)of VCR and cell proliferation and apoptosis were detected in SO-RB50/VCR cells; the protein expressions of HIF-1α, multidrug resistance associate protein(MRP)and P-glycoprotein(P-gp)were measured by Western blot.RESULTS: Compared with SO-RB50 cells, the expression levels of lncRNA HIF1A-AS1 and HIF-1α protein in SO-RB50/VCR cells were increased(P&#x003C;0.05); after inhibiting the expression of lncRNA HIF1A-AS1 in SO-RB50/VCR cells, the apoptosis rate was significantly increased(P&#x003C;0.05), optical density(OD450), the IC50 value of VCR on cells and the expression levels of HIF-1α, MRP and P-gp proteins were significantly reduced(P&#x003C;0.05); overexpression of HIF-1α attenuates the inhibitory effect of down-regulated lncRNA HIF1A-AS1 expression on drug resistance in SO-RB50/VCR cells.CONCLUSION: The lncRNA HIF1A-AS1 was highly expressed in SO-RB50/VCR cells, and inhibition of lncRNA HIF1A-AS1 expression reduced VCR resistance in SO-RB50/VCR cells by down-regulating HIF-1α expression.

Hypoxia inducible factor-1α related mechanism and TCM intervention in process of early fracture healing / 中草药·英文版

As a common clinical disease, fracture is often accompanied by pain, swelling, bleeding as well as other symptoms and has a high disability rate, even threatening life, seriously endangering patients' physical and psychological health and quality of life. Medical practitioners take many strategies for the treatment of fracture healing, including Traditional Chinese Medicine (TCM). In the early stage of fracture healing, the local fracture is often in a state of hypoxia, accompanied by the expression of hypoxia inducible factor-1α (HIF-1α), which is beneficial to wound healing. Through literature mining, we thought that hypoxia, HIF-1α and downstream factors affected the mechanism of fracture healing, as well as dominated this process. Therefore, we reviewed the local characteristics and related signaling pathways involved in the fracture healing process and summarized the intervention of TCM on these mechanisms, in order to inspirit the new strategy for fracture healing, as well as elaborate on the possible principles of TCM in treating fractures based on the HIF molecular mechanism.

New immunological aspects of peri-implantitis

ABSTRACT Objective: This study aimed to compare the levels of HIF1-α, VEGF, TNF-α, and IL-10 in the peri-implant crevicular fluid of patients with and without peri-implantitis. Methods: Forty patients, comprising 16 with and 24 without peri-implantitis were selected. Results: Patients with peri-implantitis exhibited significantly higher HIF-1α levels than those without peri-implantitis (p=0.0005). TNF-α revealed significant positive correlations with IL-10 (p=0.0008) and VEGF (p=0.0246), whereas HIF-1α and IL-10 levels (p=0.0041) demonstrated a negative and significative correlation in the peri-implantitis group. Conclusion: This study, for the first time demonstrates the balance of HIF-1α, TNFα, IL-10, and VEGF in peri-implantitis. It shows an elevated HIF-1α levels in patients with peri-implantitis, which could have stemmed from persistent inflammation- triggered hypoxia. Furthermore, the positive correlation between TNF-α and VEGF suggests intensified proinflammatory activity in peri-implantitis. Nevertheless, further studies are essential to understand these immune dynamics in peri-implantitis.

Factor inducible por hipoxia en cáncer

El oxígeno y dióxido de carbono son vitales en la respiración, sus variaciones fuera del rango fisiológico son una amenaza para la supervivencia de las células. La hipoxia es una condición común en la mayoría de los tumores malignos, la cual promueve angiogénesis y vascularización disfuncional, mayor proliferación celular y la adquisición de un fenotipo de transición epitelial a mesenquimatoso, que contribuye con la metástasis; asimismo, altera el metabolismo de las células cancerosas y genera resistencia a la terapia, ya que induce a la inactividad celular. Por tanto, la hipoxia es un factor negativo, asociado a resultados adversos en la mayoría de los tratamientos de los distintos tipos de cáncer. El factor inducible por hipoxia (HIF) es el factor de transcripción relacionado con la hipoxia en cáncer, que produce la activación de más de una centena de genes reguladores de la actividad celular, que generan funciones cruciales para el desarrollo del cáncer. El objetivo principal de la presente revisión es puntualizar la importancia de la hipoxia en la génesis del cáncer, conocer las principales moléculas que interactúan en la expresión del HIF, explicar los mecanismos moleculares de las vías involucradas en la inducción del HIF, las consecuencias celulares por su alteración y las potenciales terapias dirigidas contra este factor. Se consultaron PubMed, Scopus y SciELO, del año 1990 hasta el año 2022, y se buscaron las referencias bibliográficas en relación con las palabras clave asociadas al factor inducible por hipoxia y cáncer. En conclusión, la sobreexpresión de HIF-1α en biopsias tumorales se asocia con una mayor mortalidad de pacientes en cánceres humanos. Los posibles genes diana regulados por HIF-1α que pueden desempeñar un papel en la progresión tumoral están empezando a descubrirse. A pesar de que se han estudiado cientos de compuestos en relación con el HIF en cáncer, en la actualidad existen pocos inhibidores del HIF aprobados en el mercado mundial; asimismo, muchos estudios clínicos, en sus distintas fases en desarrollo, no muestran resultados alentadores. Probablemente, en el futuro, cuando se tenga una mejor comprensión de la estructura, funcionamiento molecular y biológico de este factor, se desarrollarán fármacos más específicos para la inhibición del HIF.

Oxygen and carbon dioxide are essential for breathing; variations in these gases outside of the normal range are a threat to cell survival. Hypoxia is a common condition that occurs in most malignant tumors, increases angiogenesis and defective vascularization, promotes cell proliferation and acquires an epithelial-mesenchymal transition phenotype, which causes metastasis. It also affects cancer cell metabolism and makes patients resistant to treatment by causing cell quiescence. As a result, hypoxia is a detrimental component that is linked to unfavorable outcomes in most cancer treatments. Through the activation of more than a hundred genes that control cell activity, which produce key functions for cancer development, the transcription factor known as hypoxia-inducible factor (HIF) is linked to hypoxia in cancer. This review's main goals are to highlight the role of hypoxia in the development of cancer, identify the key molecules that interact to promote HIF expression, explain the molecular mechanisms of the pathways that lead to HIF induction, describe the cellular effects of HIF alteration, and discuss potential HIF-targeted therapies. Articles from 1990 to 2022 were reviewed in PubMed, Scopus and SciELO databases. Keywords related to cancer and HIF were searched in bibliographical references. In conclusion, HIF-1α overexpression in tumor biopsies is associated with increased patient mortality in human cancers. Potential HIF-1α-regulated target genes that may play a role in tumor progression are starting to be identified. Although hundreds of chemicals have been studied in relation to HIF in cancer, there are currently few approved HIF inhibitors available on the global market; moreover, many clinical trials, in their various stages of development, do not show encouraging results. It is likely that in the future, when there is a better understanding of the structure, molecular and biological functioning of this factor, more specific drugs for HIF inhibition will be developed.

Effect of genetic polymorphisms rs2301113 and rs2057482 in the expression of HIF-1α protein in periodontal ligament fibroblasts subjected to compressive force

Abstract Objective Many genes and signaling molecules are involved in orthodontic tooth movement, with mechanically and hypoxically stabilized HIF-1α having been shown to play a decisive role in periodontal ligament signaling during orthodontic tooth movement. Thus, this in vitro study aimed to investigate if genetic polymorphisms in HIF1A (Hypoxia-inducible factor α-subunits) influence the expression pattern of HIF-1α protein during simulated orthodontic compressive pressure. Methodology Samples from human periodontal ligament fibroblasts were used and their DNA was genotyped using real time Polymerase chain reaction for the genetic polymorphisms rs2301113 and rs2057482 in HIF1A . For cell culture and protein expression experiments, six human periodontal ligament fibroblast cell lines were selected based on the patients' genotype. To simulate orthodontic compressive pressure in fibroblasts, a 2 g/cm2 force was applied under cell culture conditions for 48 hours. Protein expression was evaluated by Western Blot. Paired t-tests were used to compare HIF-1α expression with and without compressive pressure application and unpaired t-tests were used to compare expression between the genotypes in rs2057482 and rs2301113 (p<0.05). Results The expression of HIF-1α protein was significantly enhanced by compressive pressure application regardless of the genotype (p<0.0001). The genotypes in the genetic polymorphisms rs2301113 and rs2057482 were not associated with HIF-1α protein expression (p>0.05). Conclusions Our study confirms that compressive pressure application enhances HIF-1α protein expression. We could not prove that the genetic polymorphisms in HIF1A affect HIF-1α protein expression by periodontal ligament fibroblasts during simulated orthodontic compressive force.

Comparative study of the distribution and expression of Neuroglobin and Hypoxia-inducible factor-1α in the adult and young Yak Brain / Estudo comparativo da distribuição e expressão de neuroglobina e fator-1α indutível por hipóxia em adultos e jovens iaques (Yak Brain)

Background: The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. Aim: The study examined the expression of Neuroglobin (Ngb) and Hypoxia-inducible factor-1α (Hif-1α) in adult and young yak brain tissues, and provided researchers with meaningful insight into the anatomy, physiology, and biochemistry of this mammal. Method: The study employed immunohistochemistry (IHC), quantitative real-time PCR (qRT-PCR), and Western blot (WB) to obtain the results. Results: Ngb and Hif-1α were significantly (P<0.05) expressed in the cerebellar cortex, piriform lobe, medulla, and corpus callosum of the adult yak while in the young yak brain tissues, the protein expressions were significantly found in the white matter of the cerebellum, pineal gland, corpus callosum, and cerebellar cortex. The Ngb and Hif-1α expression showed similarities and differences. This may have resulted from similar animal species, source of nutrition, age factors, brain size, emotional activities, and communication. The findings documented that Ngb and Hif-1α are commonly expressed in various adult and young yak brain tissues. Multiple roles in the brain tissues of the adult and young yaks are involved in the expression and distribution and are proposed to play a significant role in the adaptation of the yak to the high altitude environment. Conclusion: This study provides meaningful data to understand the adaptive mechanism to hypoxia and recommended researchers to expand on the adaptive mechanism and brain tissues that are not recorded.

Contexto: O cérebro é um órgão que funciona como o centro do sistema nervoso em todos os animais vertebrados e na maioria dos invertebrados. Objetivo: O estudo examinou a expressão de neuroglobina (Ngb) e fator-1α indutível por hipóxia (Hif-1α) em tecidos cerebrais de iaques adultos e jovens e forneceu aos pesquisadores uma visão significativa da anatomia, fisiologia e bioquímica desse mamífero. Método: O estudo utilizou imuno-histoquímica (IHC), PCR quantitativo em tempo real (qRT-PCR) e western blot (WB) para a obtenção dos resultados. Resultados: Ngb e Hif-1α foram significativamente (P < 0,05) expressos no córtex cerebelar, lobo piriforme, medula e corpo caloso do iaque adulto, enquanto nos tecidos cerebrais do iaque jovem as expressões proteicas foram encontradas significativamente na substância branca do cerebelo, glândula pineal, corpo caloso e córtex cerebelar. A expressão de Ngb e Hif-1α apresentou semelhanças e diferenças. Isso pode ter resultado de espécies animais semelhantes, fonte de nutrição, fatores de idade, tamanho do cérebro, atividades emocionais e comunicação. Os resultados documentaram que o Ngb e o Hif-1α são comumente expressos em vários tecidos cerebrais de iaques adultos e jovens. Múltiplos papéis nos tecidos cerebrais de iaques adultos e jovens estão envolvidos na expressão e distribuição e são propostos para desempenhar um papel significativo na adaptação do iaque ao ambiente de alta altitude. Conclusão: Este estudo fornece dados significativos para compreender o mecanismo adaptativo à hipóxia e recomendou que os pesquisadores expandissem o mecanismo adaptativo e os tecidos cerebrais que não foram registrados.

Comparative study of the distribution and expression of Neuroglobin and Hypoxia-inducible factor-1 in the adult and young Yak Brain

Abstract Background The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. Aim The study examined the expression of Neuroglobin (Ngb) and Hypoxia-inducible factor-1 (Hif-1) in adult and young yak brain tissues, and provided researchers with meaningful insight into the anatomy, physiology, and biochemistry of this mammal. Method The study employed immunohistochemistry (IHC), quantitative real-time PCR (qRT-PCR), and Western blot (WB) to obtain the results. Results Ngb and Hif-1 were significantly (P 0.05) expressed in the cerebellar cortex, piriform lobe, medulla, and corpus callosum of the adult yak while in the young yak brain tissues, the protein expressions were significantly found in the white matter of the cerebellum, pineal gland, corpus callosum, and cerebellar cortex. The Ngb and Hif-1 expression showed similarities and differences. This may have resulted from similar animal species, source of nutrition, age factors, brain size, emotional activities, and communication. The findings documented that Ngb and Hif-1 are commonly expressed in various adult and young yak brain tissues. Multiple roles in the brain tissues of the adult and young yaks are involved in the expression and distribution and are proposed to play a significant role in the adaptation of the yak to the high altitude environment. Conclusion This study provides meaningful data to understand the adaptive mechanism to hypoxia and recommended researchers to expand on the adaptive mechanism and brain tissues that are not recorded.

Resumo Contexto O cérebro é um órgão que funciona como o centro do sistema nervoso em todos os animais vertebrados e na maioria dos invertebrados. Objetivo O estudo examinou a expressão de neuroglobina (Ngb) e fator-1 indutível por hipóxia (Hif-1) em tecidos cerebrais de iaques adultos e jovens e forneceu aos pesquisadores uma visão significativa da anatomia, fisiologia e bioquímica desse mamífero. Método O estudo utilizou imuno-histoquímica (IHC), PCR quantitativo em tempo real (qRT-PCR) e western blot (WB) para a obtenção dos resultados. Resultados Ngb e Hif-1 foram significativamente (P 0,05) expressos no córtex cerebelar, lobo piriforme, medula e corpo caloso do iaque adulto, enquanto nos tecidos cerebrais do iaque jovem as expressões proteicas foram encontradas significativamente na substância branca do cerebelo, glândula pineal, corpo caloso e córtex cerebelar. A expressão de Ngb e Hif-1 apresentou semelhanças e diferenças. Isso pode ter resultado de espécies animais semelhantes, fonte de nutrição, fatores de idade, tamanho do cérebro, atividades emocionais e comunicação. Os resultados documentaram que o Ngb e o Hif-1 são comumente expressos em vários tecidos cerebrais de iaques adultos e jovens. Múltiplos papéis nos tecidos cerebrais de iaques adultos e jovens estão envolvidos na expressão e distribuição e são propostos para desempenhar um papel significativo na adaptação do iaque ao ambiente de alta altitude. Conclusão Este estudo fornece dados significativos para compreender o mecanismo adaptativo à hipóxia e recomendou que os pesquisadores expandissem o mecanismo adaptativo e os tecidos cerebrais que não foram registrados.

Read-through circular RNA rt-circ-HS promotes hypoxia inducible factor 1α expression and renal carcinoma cell proliferation, migration and invasiveness / 北京大学学报(医学版)

OBJECTIVE@#To identify and characterize read-through RNAs and read-through circular RNAs (rt-circ-HS) derived from transcriptional read-through hypoxia inducible factor 1α (HIF1α) and small nuclear RNA activating complex polypeptide 1 (SNAPC1) the two adjacent genes located on chromosome 14q23, in renal carcinoma cells and renal carcinoma tissues, and to study the effects of rt-circ-HS on biological behavior of renal carcinoma cells and on regulation of HIF1α.@*METHODS@#Reverse transcription-polymerase chain reaction (RT-PCR) and Sanger sequencing were used to examine expression of read-through RNAs HIF1α-SNAPC1 and rt-circ-HS in different tumor cells. Tissue microarrays of 437 different types of renal cell carcinoma (RCC) were constructed, and chromogenic in situ hybridization (ISH) was used to investigate expression of rt-circ-HS in different RCC types. Small interference RNA (siRNA) and artificial overexpression plasmids were designed to examine the effects of rt-circ-HS on 786-O and A498 renal carcinoma cell proliferation, migration and invasiveness by cell counting kit 8 (CCK8), EdU incorporation and Transwell cell migration and invasion assays. RT-PCR and Western blot were used to exa-mine expression of HIF1α and SNAPC1 RNA and proteins after interference of rt-circ-HS with siRNA, respectively. The binding of rt-circ-HS with microRNA 539 (miR-539), and miR-539 with HIF1α 3' untranslated region (3' UTR), and the effects of these interactions were investigated by dual luciferase reporter gene assays.@*RESULTS@#We discovered a novel 1 144 nt rt-circ-HS, which was derived from read-through RNA HIF1α-SNAPC1 and consisted of HIF1α exon 2-6 and SNAPC1 exon 2-4. Expression of rt-circ-HS was significantly upregulated in 786-O renal carcinoma cells. ISH showed that the overall positive expression rate of rt-circ-HS in RCC tissue samples was 67.5% (295/437), and the expression was different in different types of RCCs. Mechanistically, rt-circ-HS promoted renal carcinoma cell proliferation, migration and invasiveness by functioning as a competitive endogenous inhibitor of miR-539, which we found to be a potent post-transcriptional suppressor of HIF1α, thus promoting expression of HIF1α.@*CONCLUSION@#The novel rt-circ-HS is highly expressed in different types of RCCs and acts as a competitive endogenous inhibitor of miR-539 to promote expression of its parental gene HIF1α and thus the proliferation, migration and invasion of renal cancer cells.

Expression and significance of jumonji domain-containing protein 2B and hypoxia inducible factor-1α in non-Hodgkin lymphoma tissues in children / 中国当代儿科杂志

OBJECTIVES@#To investigate the expression and significance of jumonji domain-containing protein 2B (JMJD2B) and hypoxia-inducible factor-1α (HIF-1α) in non-Hodgkin's lymphoma (NHL) tissues in children.@*METHODS@#Immunohistochemistry was used to detect the expression of JMJD2B and HIF-1α in lymph node tissue specimens from 46 children with NHL (observation group) and 24 children with reactive hyperplasia (control group). The relationship between JMJD2B and HIF-1α expression with clinicopathological characteristics and prognosis in children with NHL, as well as the correlation between JMJD2B and HIF-1α expression in NHL tissues, were analyzed.@*RESULTS@#The positive expression rates of JMJD2B (87% vs 21%) and HIF-1α (83% vs 42%) in the observation group were higher than those in the control group (P<0.05). The expression of JMJD2B and HIF-1α was correlated with serum lactate dehydrogenase levels and the risk of international prognostic index in children with NHL (P<0.05). The expression of JMJD2B was positively correlated with the HIF-1α expression in children with NHL (rs=0.333, P=0.024).@*CONCLUSIONS@#JMJD2B and HIF-1α are upregulated in children with NHL, and they may play a synergistic role in the development of pediatric NHL. JMJD2B can serve as a novel indicator for auxiliary diagnosis, evaluation of the severity, treatment guidance, and prognosis assessment in pediatric NHL.

miR-519d-3p alleviates high glucose-induced human retinal microvascular endothelial cells dysfunction and inhibits angiogenesis by targeting hypoxia inducible factor 1 subunit alpha / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To clarify the effect of miR-519d-3p on high glucose-induced human retinal microvascular endothelial cells(HRMEC)dysfunction and angiogenesis, and to elucidate the regulatory mechanism of miR-519d-3p on hypoxia inducible factor 1 subunit alpha(HIF-1α).METHODS: The normal glucose(NG)and high glucose(HG)cell models were established by inducing HRMEC with 5 and 30 mmol/L glucose, respectively. Control group: HG cell model was transfected with negative control mimics; mannitol group: the control group was added with 25 mmol/L mannitol; miR-519d-3p overexpression group: HG cell model was transfected with miR-519d-3p mimics; miR-519d-3p combined with HIF-1α overexpression group: HG cell model was co-transfected with miR-519d-3p mimics and HIF-1α overexpression vector. The expression of miR-519d-3p in each group was tested by real-time fluorescence quantitative PCR. The expression of HIF-1α protein in each group was tested by Western blotting. The binding sites between miR-519d-3p and HIF-1α were detected by luciferase reporter gene assay. The cell proliferation of each group was detected by CCK-8. The cell apoptosis of each group was tested by Hoechst 33342 staining. The protein expression of extracellular fluid inflammatory factors tumor necrosis factor-α(TNF-α), interleukin(IL)-1β and IL-6 in each group was tested by ELISA. The formation of new capillary lumen-like structures was detected by tubule formation assay.RESULTS: Compared with the NG, miR-519d-3p expression was significantly reduced in the HG cell model, while HIF-1α protein expression was significantly increased in the HG(all P&#x003C;0.01). Compared with the control group, HIF-1α protein expression was significantly reduced in the miR-519d-3p overexpression group(P&#x003C;0.01). The “CGUGAAA” sequence of miR-519d-3p could specifically bind to the “GCACUUU” sequence of HIF-1α 3'-untranslated region(3'-UTR). Compared with the control group, the miR-519d-3p overexpression group showed a significant increase in 24, 48 and 72h absorbance values, a significant decrease in cell apoptotic rate, a significant decrease in the concentrations of TNF-α, IL-1β and IL-6, and a significant decrease in the number of new capillary lumen-like structures(all P&#x003C;0.01). Compared with the miR-519d-3p overexpression group, the miR-519d-3p combined with HIF-1α overexpression group showed a significant decrease in 24, 48 and 72h absorbance values, a significant increase in cell apoptotic rate, a significant increase in the concentrations of TNF-α, IL-1β and IL-6, and a significant increase in the number of new capillary lumen-like structures(all P&#x003C;0.01). There was no difference between the control group and mannitol group in the comparison of the above indicators(all P&#x003E;0.05).CONCLUSION: miR-519d-3p expression is down-regulated while HIF-1α protein expression is up-regulated in high glucose induced HRMEC model. HIF-1α is a target gene of miR-519d-3p. The miR-519d-3p targets HIF-1α to increase cell proliferation and reduce cell apoptosis and inflammation, thereby alleviating high glucose-induced HRMEC dysfunction and inhibiting angiogenesis.

Research progress on T cell glycolytic metabolism in oral lichen planus / 口腔疾病防治

@#Oral lichen planus (OLP) is a chronic inflammatory disease of the oral mucosa. The pathogenesis of OLP is still unclear. Immune abnormalities mediated by T cells and related cytokines play a crucial role in the pathogenesis of OLP. In recent years, glycolytic metabolism-related transporters, enzymes and regulators, such as glucose transporter-1 (Glut1), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), lactate dehydrogenase A (LDHA), mammalian target of rapamycin (mTOR) and hypoxia inducible factor-1α (HIF-1a), have attracted an increasing amount of attention in OLP by regulating the proliferation and differentiation of T cells and the secretion of inflammatory factors. It has been shown that 2-deoxy-D-glucose (2-DG) or rapamycin (RAPA) inhibits the glycolytic metabolism of T cells and then inhibits OLP. This article reviews the research progress of glycolytic metabolism-related transporters, enzymes and regulatory factors in OLP in recent years.

Regulation of osteogenic differentiation under hypoxia by EphrinB2/EphB4 in MC3T3-E1 cells / 口腔疾病防治

Objective @# To investigate the effect of erythropoietin producing hepatocyte kinase receptor ligand B2-erythropoietin producing hepatocyte kinase receptor B4 (EphrinB2/EphB4) on the osteogenic differentiation of MC3T3-E1 cells in a hypoxic environment to provide experimental evidence for hypoxia regulation of osteoblast differentiation.@*Methods @# Control groups and cobalt chloride (CoCl2)-induced hypoxia groups were set up first. qRT-PCR was used to detect the mRNA expression of the osteogenic markers alkaline phosphatase (ALP), collogen1 (COL I), runt-related transcription factor 2 (RUNX2) and osteocalcin (OCN). ALP staining was used to detect the activity of cell alkaline phosphatase after osteogenic induction. The mRNA and protein expression levels of hypoxia inducible factor-1α (HIF-1α), EphrinB2 and EphB4 in the two groups were detected via qRT-PCR and Western blot. Then, the CoCl2 + inhibitor group was established. NVP-BHG712, an EphB4 phosphorylation inhibitor, was added to this group to prevent EphrinB2 from binding to EphB4 and producing signals. qRT-PCR and Western blot were used to detect the mRNA and protein expression of osteogenic markers, including ALP, RUNX2, COL I, and OCN. ALP staining and Alizarin red S staining were used to measure osteoblast differentiation and mineralization. @*Results @# Compared with the control group, the mRNA expression of the osteogenic differentiation markers ALP, RUNX2, COL-1, and OCN in MC3T3-E1 cells increased, and ALP activity and mineralization were enhanced under CoCl2-induced hypoxia in vitro (P<0.05). Additionally, the expression of HIF-1α, EphrinB2 and EphB4 was upregulated at the mRNA and protein levels under hypoxia (P<0.05). When NVP-BHG712 was used to block the connection between EphrinB2 and EphB4, the expression of osteogenic markers and ALP activity and mineralization were decreased (P<0.05).@*Conclusion@#EphrinB2/EphB4 can promote osteogenic differentiation of MC3T3-E1 cells and increase the expression of osteogenic markers and tissue mineralization in a hypoxic environment.

Regulating anaerobic metabolism and promoting myocardial ischemia-hypoxia injury by diesel particulate matter and its key component benzoapyrene via targeting oxygen sensors / 环境与职业医学

Background The exposure to diesel particulate matter (DPM) and its polycyclic aromatic hydrocarbons (PAH) is closely related to the morbidity and mortality of ischemic heart disease (IHD). However, it is unclear what key components and targets of DPM exposure involve in myocardial ischemia-hypoxia injury and associated mechanisms. Objective To identify key PAH components of DPM that act on myocardial hypoxic injury, andclarify the role of oxygen sensors-regulated anaerobic metabolism in DPM and key components-induced hypoxic injury and the targets of the key PAH components. Methods Human cardiomyocyte cell line AC16 cells were exposed to 0, 1, 5, and 10 μg·mL−1 DPM in a high glucose DMEM medium with 10% fetal bovine serum (FBS) (HGM) or low FBS (0.5%) in high glucose DMEM medium (LFM), for 12 h under 2% O2, and expression of hypoxia-inducible factor-1α (HIF-1α), Bax, and Cleaved-caspase3 was determined by Western blotting. Under normal condition, the cell viability was detected after PAH exposure for 12 h. Under the condition of ischemia-hypoxia model, cells were exposed to 0, 0.005, 0.5, and 5 µg·mL−1 PAH for 12 h, and the protein expression of HIF-1α, Bax, and Cleaved-caspase3 was determined. After exposure to DPM or PAH for 12 h, the contents of pyruvate and lactate in cells were detected. Pretreatment with glycolysis inhibitor GSK2837808A was used to explore the role of glycolysis in DPM and benzo[a]pyrene (BaP)-induced hypoxia injury. A molecular docking technique was used to analyze the binding affinity between PAH and oxygen sensors (prolyl hydroxylase domain-containing protein 2, PHD2, and factor-inhibiting hypoxia-inducible factor 1, FIH1), and the protein levels of PHD2, FIH1, and hydroxyl-HIF-1-alpha (OH-HIF-1α) after the DPM or BaP treatment were further determined. Results Under hypoxia, DPM exposure in the LFM induced the expression of HIF-1α, Bax, and Cleaved-caspase3 (P<0.01). Therefore, hypoxia and LFM were selected as the basic ischemia and hypoxia condition. Except for anthracene (Ant) (P>0.05), other PAH decreased cell viability when the concentration was above 1 μg·mL−1 (P<0.05). All concentrations of BaP induced the expression of HIF-1α protein (P<0.05), and the protein levels of Bax and Cleaved-caspase3 were up-regulated after the 0.5 and 5 µg·mL−1 BaP exposure (P<0.01). After exposure to DPM (1, 5 and 10 μg·mL−1) or BaP (0.5 and 5 μg·mL−1), the intracellular pyruvate and lactate contents increased (P<0.05). The glycolysis inhibitor co-treatment decreased the levels of HIF-1α, Bax, and Cleaved-caspase3 proteins compared with the DPM or BaP exposure group for 12 h (P＜0.05). The binding abilities of the five PAHs to the oxygen sensors PHD2 and FIH1 were strong, and BaP was the strongest. Although the DPM or BaP exposure had no effects on the protein levels of PHD2 and FIH1 in AC16 cells (P＜0.05), the protein level of OH-HIF-1α was decreased (P＜0.01). Conclusion BaP exposure can promote hypoxia and injury of myocardial cells and is the key PAH component of DPM that induces myocardial ischemia and hypoxia injury. BaP exposure inhibits the hydroxylation function of PHD2 on HIF-1α by combining with PHD2, decreases the level of OH-HIF-1α and induces HIF-1α accumulation. And then HIF-1α promotes anaerobic metabolism and accelerates ischemia and hypoxia injury of myocardial cells.

Mechanism of regulatory effect of recombinant human HMGB1 on endothelial cell angiogenesis / 器官移植

Objective To unravel the possible mechanism of the role of recombinant human high mobility group box 1 (rhHMGB1) protein in regulating the angiogenesis of endothelial cells. Methods Endothelial cells were divided into the control group, bone marrow mesenchymal stem cells (MSC) supernatant group and rhHMGB1 group. The proliferation and survival of endothelial cells were detected by cell counting kit(CCK)-8 assay. The relative expression levels of vascular endothelial growth factor (VEGF), Yes-associated protein (YAP), CD31 and hypoxia inducible factor (HIF)-1α proteins were determined by Western blot. The relative expression levels of VEGF, YAP, CD31 and HIF-1α messenger RNA (mRNA) were detected by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). The migration ability of endothelial cells was assessed by Transwell chamber test. The localization of YAP was detected by immunofluorescence staining. Results Compared with the control group, the migration rate of endothelial cells was increased in the rhHMGB1 group (P < 0.05), and the cell migration rate was enhanced over time. Compared with the control group, the relative expression levels of VEGF and p-YAP proteins were up-regulated in the MSC supernatant group, and the differences were statistically significant (both P < 0.05). Compared with the control group, the relative expression levels of VEGF and HIF-1α proteins, VEGF and CD31 mRNA and YAP and p-YAP proteins were up-regulated, and YAP/p-YAP ratio was increased in the rhHMGB1 group, and the differences were statistically significant (all P < 0.05). Compared with the MSC supernatant group, the relative expression levels of CD31 mRNA and YAP protein were up-regulated, and the YAP/p-YAP ratio was increased in the rhHMGB1 group, and the differences were statistically significant (all P < 0.05). Conclusions Exogenous high-concentration rhHMGB1 may promote the migration ability of endothelial cells and up-regulate the expression levels of angiogenesis-related proteins by regulating the recruitment of YAP to the nucleus.

Protective Effect of Huangqi Baihe Granules on Acute Brain Injury in Rats with High Altitude Hypoxia Based on HIF-1α/NF-κB/NLRP3 Signal Pathway / 中国实验方剂学杂志

ObjectiveTo observe the effect of Huangqi Baihe granules on the hypoxia-inducible factor 1α （HIF-1α）/nuclear factor-κB （NF-κB）/NOD-like receptor hot protein domain related protein 3 （NLRP3） signaling pathway in a rat model of high altitude hypoxia. MethodSixty male SPF SD rats were randomly divided into blank group， model group， dexamethasone group （5 mg·kg-1）， and high， middle， and low-dose groups of Huangqi Baihe granules （4.1， 2.05， 1.025 g·kg-1）. Among them， each Chinese medicine group was administrated orally for continuously 14 d， once a day， and the dexamethasone group was injected intraperitoneally for continuously 3 d as the positive control group. On the 15th d， the model group， dexamethasone group， and high， middle， and low dose groups of Huangqi Baihe granules were exposed to the simulated high altitude， low pressure， and low oxygen environment in the animal low-pressure simulation cabin， and the exposure lasted for 3 d. Blood was collected from the abdominal aorta and serum was separated， and the brain tissue was taken after being killed. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in brain tissue. Enzyme-linked immunosorbent assay （ELISA） was used to detect the content of tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， and interleukin-1β （IL-1β） in rat serum. Western blot was used to detect HIF-1α， NLRP3， phosphorylated nuclear factor-κB （p-NF-κB）， NF-κB， desquamation D （GSDMD）， and cysteine aspartate-specitis protein-1（Caspase-1） in rats of each group. The mRNA expression levels of HIF-1α， NLRP3， NF-κB p65， GSDMD， and Caspase-1 were detected by real-time quantitative polymerase chain reaction （Real-time PCR）. ResultThe results of HE staining showed that as compared with the normal group， the pathological sections of brain tissues in the model group showed that pyramidal cells were loosely arranged and distributed in disorder， with different sizes. Compared with the model group， the pathological changes in pyramidal cells in the dexamethasone group and high and middle-dose groups of Huangqi Baihe granules were reduced. The results of ELISA showed that as compared with the normal group， the content of TNF-α， IL-6， and IL-1β in the serum of rats in the model group was significantly higher （P<0.01）. Compared with the model group， the content of TNF-α， IL-6， and IL-1β in the serum of rats in the dexamethasone group and high and middle-dose groups of Huangqi Baihe granules decreased significantly （P<0.05， P<0.01）. The results of Western blot showed that as compared with the normal group， the relative protein expression levels of HIF-1α， NLRP3， p-NF-κB p65， GSDMD， and Caspase-1 in the brain tissue of the model group were significantly higher （P<0.01）. As compared with the model group， the relative expressions of HIF-1α， NLRP3， p-NF-κB p65， GSDMD， and Caspase-1 in the brain tissue of rats in the dexamethasone group and the high-dose group of Huangqi Baihe granules were significantly decreased （P<0.05， P<0.01）. The relative protein expression levels of HIF-1α， NLRP3， p-NF-κB p65， and Caspase-1 in the brain tissue of rats in the middle-dose group of Huangqi Baihe granules decreased significantly （P<0.01）， and the relative protein expression of HIF-1α in the brain tissue of rats in the low-dose group of Huangqi Baihe granules was reduced （P<0.05）. The Real-time PCR analysis showed that as compared with the normal group， the mRNA expression levels of HIF-1α， NLRP3， NF-κB p65， GSDMD， and Caspase-1 in the brain tissue of the model group were significantly increased （P<0.01）. As compared with the model group， the mRNA expression levels of HIF-1α， NLRP3， NF-κB p65， GSDMD， and Caspase-1 in the brain tissue of rats in the dexamethasone group were significantly decreased （P<0.01）. The mRNA expression levels of HIF-1α， NF-κB p65， GSDMD， and Caspase-1 in the brain tissue of rats in the high-dose group of Huangqi Baihe granules decreased significantly （P<0.01）. The mRNA expression levels of HIF-1α， NLRP3， and Caspase-1in the brain tissue of rats in the middle-dose group of Huangqi granules decreased （P<0.05， P<0.01）. ConclusionThe protective effect of Huangqi Baihe granules on acute brain injury in low-pressure hypoxic rats may be related to the HIF-1α/NF-κB/NLRP3 signaling pathway.