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.

Regulatory effect of miR-210 in hypoxia-induced epithelial-mesenchymal transition of pancreatic cancer PANC1 cells / 中华胰腺病杂志

Objective:To explore the regulatory role of miR-210 in hypoxia-induced epithelial-mesenchymal transition (EMT) of pancreatic cancer PANC1 cells.Methods:PANC1 cells cultured in normoxia and hypoxia were established in normoxia group and hypoxia group. Recombinant plasmid carrrying miR-210 mimics and miR-210 antagomirs were constructed. The recombinant plasmids were transfected with PANC1 cells cultured in normoxia and hypoxia by liposome method to establish cell lines of miR-210 overexpression (miR-210 mimics normoxia group) and miR-210 expression inhibition (miR-210 antagomirs hypoxia group). The blank plasmids were transfected to establish blank plasmid normoxia group and blank plasmid hypoxia group. Relative expression levels of miR-210 for PANC1 cells were determined by qRT-PCR in each group. Western blot was used to measure the expressions of HIF-1α, NF-κB and EMT related protein such as E-cadherin, β-catenin, vimentin and N-cadherin. Cell relative viability under gemcitabine and in vitro cell invasion ability were detected by CCK8 and Transwell chamber experiments, respectively. Results:The relative expressions of miR-210 in hypoxia group and miR-210 mimics normoxia group were significantly higher than those in normoxia group and blank plasmid normoxia group. However, there were significantly lower in miR-210 antagomirs hypoxia group than those in blank plasmid hypoxia group. The expression levels of HIF-1α, NF-κB and mesenchymal cell markers such as vimentin and N-cadherin in hypoxia group were significantly higher than those in normoxia group (0.74±0.06 vs 0.40±0.05, 1.58±0.16 vs 1.09±0.13, 0.46±0.04 vs 0.17±0.02, 1.27±0.07 vs 0.40±0.03) and the epithelial cell markers such as E-cadherin and β-catenin were significantly lower (0.40±0.07 vs 0.77±0.10, 0.35±0.02 vs 0.94±0.08). The expression levels of HIF-1α, NF-κB, vimentin and N-cadherin in miR-210 mimics normoxia group were significantly higher than those in blank plasmid normoxia group (0.91±0.08 vs 0.40±0.06, 1.52±0.17 vs 1.05±0.14, 0.82±0.06 vs 0.66±0.07, 0.76±0.04 vs 0.46±0.03) and E-cadherin and β-catenin were significantly lower (0.38±0.07 vs 0.65±0.09, 0.50±0.03 vs 0.94±0.08). The expression levels of HIF-1α, NF-κB, vimentin and N-cadherin in miR-210 antagomirs hypoxia group were significantly lower than those in blank plasmid hypoxia group (0.31±0.05 vs 0.55±0.06, 0.68±0.05 vs 1.11±0.13, 0.41±0.03 vs 0.74±0.07, 0.69±0.06 vs 0.78±0.05), while E-cadherin and β-catenin were significantly higher (0.72±0.13 vs 0.50±0.07, 0.71±0.04 vs 0.54±0.05). All the differences among the groups were statistically significant (all P value <0.05). Under gemcitabine, the relative viability of PANC1 cells in hypoxia group and miR-210 mimics normoxia group were significantly higher than those in normoxia group and blank plasmid normoxia group at 48 h (1.10±0.10 vs 0.76±0.05, 1.46±0.11 vs 1.12±0.09) and 72 h (1.12±0.13 vs 0.76±0.05, 1.54±0.13 vs 1.12±0.09) accordingly. However, there were significantly lower in miR-210 antagomirs hypoxia group than those in blank plasmid hypoxia group at 48 and 72 h (0.75±0.09 vs 1.10±0.10, 1.19±0.12 vs 1.46±0.11). All the differences among the groups were statistically significant (all P value <0.05). The number of transmembrane cells in hypoxia group and miR-210 mimics normoxia group was significantly higher than those in normoxia group and blank plasmid normoxia group, respectively (417.50±81.22 vs 228.30±47.71, 371.30±72.81 vs 245.00±33.62 per high field), while those in miR-210 antagomirs hypoxia group was significantly lower than those in blank plasmid hypoxia group (228.30±54.01 vs 433.30±65.63 per high field). All the differences among the groups were statistically significant (all P value <0.05). Conclusions:miR-210 could weaken the sensitivity to gemcitabine and promote the invasion of PANC1 cells by regulating the occurrence of the hypoxia-induced epithelial-mesenchymal transition.

Mechanism of Xumingtang in Gu Jin Lu Yan for Treatment of Ischemic Stroke Based on HIF-1α/NLRP3 Pathway-mediated Pyroptosis / 中国实验方剂学杂志

ObjectiveTo investigate the mechanism of Xumingtang in Gu Jin Lu Yan （《古今录验》） in regulating cell pyroptosis through the hypoxia-inducible factor-1α （HIF-1α）/NOD-like receptor pyrin domain-containing protein 3 （NLRP3） pathway in ischemic stroke （IS）. MethodSD rats were randomly divided into a sham operation group， a model group， low- and high-dose Xumingtang groups， and a metformin group， with 20 rats in each group. Oral administration was performed for 3 days， and tissue samples were collected. Differential messenger RNA （mRNA） was screened using high-throughput sequencing， and Gene Ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway analyses were performed on key differentially expressed genes. The modified neurological severity score （mNSS） and 2，3，5-triphenyltetrazolium chloride （TTC） staining were used to evaluate the effect of brain infarction. Hematoxylin-eosin （HE） staining was used for pathological morphological observation of brain tissue. Enzyme-linked immunosorbent assay （ELISA） was used to compare the levels of interleukin-1β （IL-1β） and interleukin-18 （IL-18） in the ischemic cortical region. Double staining immunohistochemistry was used to detect the co-localization of HIF-1α and NLRP3. Real-time quantitative polymerase chain reaction （PCR） was performed to detect the mRNA expression of NLRP3， HIF-1α， Caspase-1 （CASP-1）， and gasdermin D （GSDMD）. Western blot was used to detect the protein expression of HIF-1α， NLRP3， CASP-1， and GSDMD. ResultA total of 5 705 differentially expressed genes （2 733 downregulated and 2 972 upregulated） were obtained by mRNA sequencing. After conversion to homologous genes and intersection with the pyroptosis gene set， 95 key differentially expressed pyroptosis genes were obtained. Compared with the sham operation group， the model group showed significantly increased mNSS scores， larger brain infarction areas （P<0.01）， diverse neuronal morphology， disordered arrangement， widened cell gaps， significantly increased levels of IL-1β and IL-18 in the ischemic cortical region （P<0.01）， enhanced co-localization fluorescence intensity， and significantly increased mRNA and protein expression levels of HIF-1α， NLRP3， CASP-1， and GSDMD （P<0.01）. Compared with the model group， the high-dose Xumingtang group showed the most significant improvement in neurological function scores and brain infarction areas （P<0.01）. The neuronal integrity and arrangement were more complete， and the cell gaps were narrower in all groups with drug treatment， with significantly reduced co-localization fluorescence intensity. Xumingtang could reduce the levels of IL-1β， IL-18， and the mRNA and protein expression of HIF-1α， NLRP3， CASP-1， and GSDMD （P<0.05， P<0.01）， with the high-dose Xumingtang group showing the most significant effect （P<0.01）. ConclusionXumingtang in Gu Jin Lu Yan can inhibit cell pyroptosis and promote neurological function recovery after IS， which may be related to the inhibition of the HIF-1α/NLRP3 pathway.

Effect of salidroside on choroidal thickness and expression of hypoxia-inducible factor-1α, dopamine and its receptor in guinea pigs with myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To examine the effects of salidroside on choroidal thickness, hypoxia-inducible factor-1α(HIF-1α), dopamine(DA)and its D1 receptor expression in guinea pigs with lens-induced myopia(LIM).METHODS: A total of 18 two-week-old guinea pigs were randomly divided into the normal control(NC)group, the LIM group, and the LIM + salidroside(LIM+SA)group, with 6 guinea pigs in each group. The guinea pigs in the NC group were fed normally and intragastrically administered with 2 mL/d saline; those in the LIM group wore a -5D lens in front of their right eyes to establish a myopia model, then they were intragastrically administered with 2 mL/d saline. Finally, those in the LIM+SA group wore glasses along with intragastric administration of 2 mL/d salidroside at a dose of 100 mg/kg. The refraction, axial length, and choroidal thickness of guinea pigs in each group were measured 4wk following the establishment of the model. In addition, the relative mRNA expression and protein content of HIF-1α in the choroid and retina of guinea pigs in each group were detected by real-time quantitative PCR(qPCR)and immunohistochemistry(IHC). Finally, the DA concentration and its D1 receptor expression were detected by enzyme-linked immunosorbent assay(ELISA)and Western blot.RESULTS: At 4wk after model establishment, guinea pigs of LIM group and LIM+SA group exhibited increased negative refraction of the right eye, prolonged axial length, and decreased choroidal thickness compared to the NC group. The relative mRNA expression and protein content of HIF-1α in the choroid and retina of the guinea pigs increased. The concentration of DA and the expression of its D1 receptor both decreased. Moreover, compared to the LIM group, the diopter of the right eye of guinea pigs in LIM+SA group significantly reduced, the axial length was shorter, the thickness of choroid increased, the relative mRNA expression and protein content of HIF-1α in the choroid and retina decreased and the concentration of DA and the expression of its D1 receptor both increased.CONCLUSION: Salidroside can delay myopia progression in myopic guinea pigs by affecting choroidal thickness and the expression of HIF-1α, DA and its D1 receptor.

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.

Shikonin induces hepatocellular carcinoma cell apoptosis by suppressing PKM2/PHD3/HIF-1α signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the mechanism of shikonin-induced death of human hepatocellular carcinoma SMMC-7721 cells.@*METHODS@#Cultured SMMC-7721 cells and normal hepatocytes (L-02 cells) were treated with 4, 8, or 16 μmol/L shikonin, and the changes in cell viability was assessed using MTT assay. The levels of ATP and lactic acid in the cell cultures were detected using commercial kits. Co-immunoprecipitation and immunofluorescence staining were used to determine the relationship among pyruvate kinase M2 (PKM2), prolyl hydroxylase 3 (PHD3), and hypoxia-inducible factor-1α (HIF-1α). The expressions of PHD3, PKM2, HIF-1α, Bax, cleaved caspase-3, and Bcl-2 in SMMC-7721 cells were detected with Western blotting, and cell apoptosis was analyzed with annexin V-FITC/PI staining. The effects of RNA interference of PKM2 on PHD3 and HIF-1α expressions in SMMC-7721 cells were detected using Western blotting.@*RESULTS@#The IC50 of shikonin against SMMC-7721 and L-02 cells was 8.041 μmol/L and 31.75 μmol/L, respectively. Treatment with shikonin significantly inhibited the protein expressions of PKM2, HIF-1α and PHD3 and nuclear translocation of PKM2 and HIF-1α in SMMC-7721 cells. Coimmunoprecipitation and immunofluorescence staining confirmed that shikonin inhibited the formation of PKM2/PHD3/HIF-1α complex and significantly reduced the contents of lactic acid and ATP in SMMC-7721 cells (P < 0.05). The expressions of PHD3 and HIF-1α decreased significantly after PKM2 knockdown (P < 0.05). Shikonin treatment significantly increased the apoptosis rate, enhanced the expressions of Bax and cleaved caspase-3, and decreased Bcl-2 expression in SMMC-7721 cells (P < 0.05).@*CONCLUSIONS@#Shikonin induces apoptosis of SMMC-7721 cells possibly by inhibiting aerobic glycolysis through the PKM2/PHD3/HIF-1α signaling pathway to cause energy supply dysfunction in the cells.

Aerobic glycolysis in colon cancer is repressed by naringin via the HIF1Α pathway / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Metabolic reprogramming is a common phenomenon in cancer, with aerobic glycolysis being one of its important characteristics. Hypoxia-inducible factor-1α (HIF1Α) is thought to play an important role in aerobic glycolysis. Meanwhile, naringin is a natural flavanone glycoside derived from grapefruits and many other citrus fruits. In this work, we identified glycolytic genes related to HIF1Α by analyzing the colon cancer database. The analysis of extracellular acidification rate and cell function verified the regulatory effects of HIF1Α overexpression on glycolysis, and the proliferation and migration of colon cancer cells. Moreover, naringin was used as an inhibitor of colon cancer cells to illustrate its effect on HIF1Α function. The results showed that the HIF1Α and enolase 2 (ENO2) levels in colon cancer tissues were highly correlated, and their high expression indicated a poor prognosis for colon cancer patients. Mechanistically, HIF1Α directly binds to the DNA promoter region and upregulates the transcription of ENO2; ectopic expression of ENO2 increased aerobic glycolysis in colon cancer cells. Most importantly, we found that the appropriate concentration of naringin inhibited the transcriptional activity of HIF1Α, which in turn decreased aerobic glycolysis in colon cancer cells. Generally, naringin reduces glycolysis in colon cancer cells by reducing the transcriptional activity of HIF1Α and the proliferation and invasion of colon cancer cells. This study helps to elucidate the relationship between colon cancer progression and glucose metabolism, and demonstrates the efficacy of naringin in the treatment of colon cancer.

Targeting TRMT5 suppresses hepatocellular carcinoma progression via inhibiting the HIF-1α pathways / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Accumulating evidence has confirmed the links between transfer RNA (tRNA) modifications and tumor progression. The present study is the first to explore the role of tRNA methyltransferase 5 (TRMT5), which catalyzes the m1G37 modification of mitochondrial tRNAs in hepatocellular carcinoma (HCC) progression. Here, based on bioinformatics and clinical analyses, we identified that TRMT5 expression was upregulated in HCC, which correlated with poor prognosis. Silencing TRMT5 attenuated HCC proliferation and metastasis both in vivo and in vitro, which may be partially explained by declined extracellular acidification rate (ECAR) and oxygen consumption rate (OCR). Mechanistically, we discovered that knockdown of TRMT5 inactivated the hypoxia-inducible factor-1 (HIF-1) signaling pathway by preventing HIF-1α stability through the enhancement of cellular oxygen content. Moreover, our data indicated that inhibition of TRMT5 sensitized HCC to doxorubicin by adjusting HIF-‍1α. In conclusion, our study revealed that targeting TRMT5 could inhibit HCC progression and increase the susceptibility of tumor cells to chemotherapy drugs. Thus, TRMT5 might be a carcinogenesis candidate gene that could serve as a potential target for HCC therapy.

Hypoxia-induced ROS aggravate tumor progression through HIF-1α-SERPINE1 signaling in glioblastoma / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Hypoxia, as an important hallmark of the tumor microenvironment, is a major cause of oxidative stress and plays a central role in various malignant tumors, including glioblastoma. Elevated reactive oxygen species (ROS) in a hypoxic microenvironment promote glioblastoma progression; however, the underlying mechanism has not been clarified. Herein, we found that hypoxia promoted ROS production, and the proliferation, migration, and invasion of glioblastoma cells, while this promotion was restrained by ROS scavengers N-acetyl-L-cysteine (NAC) and diphenyleneiodonium chloride (DPI). Hypoxia-induced ROS activated hypoxia-inducible factor-1α (HIF-1α) signaling, which enhanced cell migration and invasion by epithelial-mesenchymal transition (EMT). Furthermore, the induction of serine protease inhibitor family E member 1 (SERPINE1) was ROS-dependent under hypoxia, and HIF-1α mediated SERPINE1 increase induced by ROS via binding to the SERPINE1 promoter region, thereby facilitating glioblastoma migration and invasion. Taken together, our data revealed that hypoxia-induced ROS reinforce the hypoxic adaptation of glioblastoma by driving the HIF-1α-SERPINE1 signaling pathway, and that targeting ROS may be a promising therapeutic strategy for glioblastoma.

Role of Mitophagy in Myocardial Ischemia/Reperfusion Injury and Chinese Medicine Treatment / 中国结合医学杂志

Mitophagy is one of the important targets for the prevention and treatment of myocardial ischemia/reperfusion injury (MIRI). Moderate mitophagy can remove damaged mitochondria, inhibit excessive reactive oxygen species accumulation, and protect mitochondria from damage. However, excessive enhancement of mitophagy greatly reduces adenosine triphosphate production and energy supply for cell survival, and aggravates cell death. How dysfunctional mitochondria are selectively recognized and engulfed is related to the interaction of adaptors on the mitochondrial membrane, which mainly include phosphatase and tensin homolog deleted on chromosome ten (PTEN)-induced kinase 1/Parkin, hypoxia-inducible factor-1 α/Bcl-2 and adenovirus e1b19k Da interacting protein 3, FUN-14 domain containing protein 1 receptor-mediated mitophagy pathway and so on. In this review, the authors briefly summarize the main pathways currently studied on mitophagy and the relationship between mitophagy and MIRI, and incorporate and analyze research data on prevention and treatment of MIRI with Chinese medicine, thereby provide relevant theoretical basis and treatment ideas for clinical prevention of MIRI.

Research advance on the role of hypoxia-inducible factor-1 in oxygen-induced retinal neovascularization / 中华实用儿科临床杂志

Hypoxia-inducible factor-1 (HIF-1) is an essential transcription factor, which mediates the transcription of multiple target genes to adapt the body for hypoxia.Oxygen-induced retinal neovascularization (RNV) is an important pathological process of retinopathy of prematurity (ROP). By mediating the transcription of vascular endothelial growth factors, angiopoietin and platelet-derived growth factors, HIF-1 can promote RNV and then lead to ROP.Therefore, HIF-1 plays a vital role in the pathological process of ROP.In this paper, the recent research progress on the role of HIF-1 in oxygen-induced RNV was summarized in order to further the understanding of ROP pathogenesis and treatment.

Diurnal variation of serum hypoxia inducible factor-1 α in obese patients with obstructive sleep apnea / 国际外科学杂志

Objective:To observe the diurnal changes of serum hypoxia inducible factor-1α (HIF-1α) and its relationship with polysomnography (PSG) parameters in obese patients with obstructive sleep apnea (OSA).Methods:In this study, 64 obese subjects with OSA (experimental group) and 24 normal subjects (control group) were included. PSG monitoring was performed in all subjects, and peripheral blood samples were collected at night and next early morning to detect the expression level of HIF-1 α mRNA and protein concentration in serum. The data were analyzed by SPSS25.0 software. The counting data was represented by n(%), and t-tests were used for inter group comparisons. The measurement data of normal distribution adopted mean ± standard deviation ( ± s), and the inter group comparison adopted Chi-square. Serum HIF-1α mRNA levels and protein concentrations in the two groups were compared and analyzed by Two-way ANOVA, and Spearman rank correlation was used to analyze the correlation. Results:The ratio of male to female in the control group was 15: 9 and the average age was (39.25 ±10.58) years old, while that in the experimental group was 41∶24 with an average age of (41.31 ±15.20) years. The body mass index (BMI) of experimental group was higher, while all the relevant parameters recorded by PSG were significantly different between two groups ( P<0.001). The results showed that there was no significant difference in the expression of HIF-1α mRNA between the control group and the experimental group ( P=0.914), or between night and morning ( P=0.167). The concentration of HIF-1α protein in the control group was significantly lower than that in the experimental group ( P<0.001), but there was no significant difference in the concentration of HIF-1α protein in the same group at night and in the morning ( P=0.798). The results of correlation analysis showed that there was a significant correlation between PSG related indexes(AHI, minimum blood oxygen, mean blood oxygen and SIT90), night and morning mRNA expression and protein concentration ( P<0.05). Conclusions:Compared with normal people, the concentration of serum HIF-1 α protein in obese patients with OSA is higher, but there is no difference between night and morning. The process of HIF-1 α induced by CIH may be involved in post-translational regulation rather than transcription, and other compensatory mechanisms may also be involved.

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.

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.

Mechanism of curcumin inhibiting choroidal neovascularization in brown Norway rat / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the mechanism of curcumin inhibiting the choroidal neovascularization(CNV)of brown Norway(BN)rats.METHODS: CNV model of 36 BN rats was established through laser photocoagulation induction, and they were divided into 6 groups with 6 rats in each group. Normal group was fed normally with no intervention, while 532nm laser photocoagulation was used to establish a experimental CNV model in BN rats. Rats after modeling were respectively intervened for 14d and divided into model group, ranibizumab group, curcumin low [100mg/(kg·d)], medium [200mg/(kg·d)], and high [400mg/(kg·d)] dose group. The model group was given intragastric administration of saline for 14d, ranibizumab(10mg/mL, 0.2mL/dose)was injected at 2d after photocoagulation with 5μL once for rats in ranibizumab group, and different concentrations of curcumin were intragastrically administrated to the rats in low, medium and high groups for 14d. Fundus photography, fundus fluorescein angiography(FFA)and indocyanine green angiography(ICGA)examination were performed at 14d after photocoagulation. Ocular histopathological specimens of rats with CNV were made, and the central thickness of CNV were observed by HE staining. Ocular histopathological specimens were made, and the expressions of AKT/p-AKT/HIF-1α/VEGF signaling pathway-related proteins were observed by immunohistochemistry. The mRNA relative expressions of AKT/HIF-1α/VEGF factor in CNV tissues were detected by RT-qPCR, and the protein expressions of AKT/p-AKT/HIF-1α/VEGF factor in CNV tissues were detected by Western-blot.RESULTS: CNV generation rates in the model group, the ranibizumab group, and the low, medium and high-dose curcumin groups were 78.18%, 73.21%, 77.19%, 75.86%, 74.55%, respectively, which were higher than 70%. The average absorbance were 182.12±6.59, 119.22±8.03, 166.45±8.33, 164.34±5.69, 149.22±6.45, respectively; the ranibizumab group was significantly lower than the model group(P&#x0026;#x003C;0.05); the low-dose, medium-dose and high-dose groups were significantly higher than the ranibizumab group(P&#x0026;#x003C;0.05), and the curcumin high-dose group was significantly lower than the model group(P&#x0026;#x003C;0.05). HE staining showed that the retinal tissue structure of BN rats in normal group was clear and neatly arranged. The central thickness of CNV in the ranibizumab group was significantly reduced at 14d after photocoagulation compared with the model group(P&#x0026;#x003C;0.05); While the curcumin high-dose group was significantly reduced compared with the model group(P&#x0026;#x003C;0.05), but increased when compared with ranibizumab group(P&#x0026;#x003C;0.05). Immunohistochemistry results showed that AKT, p-AKT, HIF-1α, and VEGF factors were negatively expressed in the retinal tissue structure of BN rats in the normal group, and no brown-yellow reactants were found. The expression of AKT, p-AKT, HIF-1α, and VEGF factors in the model group were higher than that in the normal group at 14d after photocoagulation(P&#x0026;#x003C;0.05); the ranibizumab group was lower than the model group(P&#x0026;#x003C;0.05). While the expression of the curcumin high-dose group was significantly decreased compared with the model group(P&#x0026;#x003C;0.05), but significantly increased when compared with ranibizumab group(P&#x0026;#x003C;0.05). The mRNA results showed that the relative expression levels of AKT, HIF-1α and VEGF mRNA in the model group at 14d after photocoagulation were higher than those of the normal group(P&#x0026;#x003C;0.05); the ranibizumab group was lower than the model group(P&#x0026;#x003C;0.05). While curcumin high-dose group was significantly decreased compared with the model group(P&#x0026;#x003C;0.05), but significantly increased when compared with ranibizumab group(P&#x0026;#x003C;0.05). Western-blot results showed that there was no significant difference in the relative expression of AKT protein among each experimental groups at 14d after photocoagulation. The relative expression of p-AKT protein in the model group was significantly higher than that in the normal group(P&#x0026;#x003C;0.05); the ranibizumab group was significantly lower than the model group(P&#x0026;#x003C;0.05); the curcumin high-dose group was significantly lower than the model group(P&#x0026;#x003C;0.05). The relative expression levels of HIF-1α protein were significantly higher in the model group than in the normal group(P&#x0026;#x003C;0.05), and the ranibizumab group was lower than in the model group(P&#x0026;#x003C;0.05). The relative expression levels of HIF-1α protein was lower in the curcumin high-dose group than in the model group(P&#x0026;#x003C;0.05)but higher than ranibizumab group(P&#x0026;#x003C;0.05). The relative expression level of VEGF protein was significantly lower in the curcumin medium/high-dose group than in the model group(P&#x0026;#x003C;0.05).CONCLUSION: Curcumin at 400mg/(kg·d)has an inhibitory effect on CNV in BN rats. The mechanism may be closely related to inhibiting the activation of AKT/p-AKT/HIF-1α/VEGF signaling pathways.

Effect of Xielitang on TLR4/NF-κB/HIF-1α Signaling Pathway in Mice with Ulcerative Colitis / 中国实验方剂学杂志

ObjectiveTo explore the protective effect of Xielitang on ulcerative colitis （UC） mice induced by dextran sodium sulfate （DSS） and its possible mechanism. MethodSixty C57BL/6 mice were randomly divided into normal group， model group， sulfasalazine group and and low-， medium-， and high-dose Xielitang groups. Free drinking DSS solution to build the chronic UC model mice. Except for normal group， other groups were given 1.5% DSS for 3 cycles of drinking （days 1-7， days 22-28 and days 43-49） and distilled water for the rest of the time （days 8-21， days 29-42 and days 50-63）. After the first cycle， corresponding drugs were given for 42 days. The changes of general condition， body weight and disease activity index （DAI） score of mice were daily recorded during the experiment. At the end of the treatment， serum and colon tissue samples were collected， colon length was measured， intestinal weight index and colonic mucosal injury （CMDI） score were calculated. The pathological status of colon tissue was observed by hematoxylin-eosin （HE） staining. The levels of interleukin-6 （IL-6）， interleukin-10 （IL-10） and tumour necrosis factor-α （TNF-α） were measured by enzyme-linked immunosorbent assay （ELISA）. The gene and protein expressions of Toll like receptor 4 （TLR4）， nuclear transcription factor-κB （NF-κB） and hypoxia inducible factor-1α （HIF-1α） in colon tissue was detected by Real-time quantitative polymerase chain reaction （Real-time PCR） and Western blot. ResultCompared with the normal group， the body weight， colon length and IL-10 content in the model group were significantly decreased （P<0.01）， DAI score， intestinal weight index， CMDI score， IL-6 and TNF-α contents， and mRNA and protein expression levels of TLR4， NF-κB and HIF-1α in the model group were significantly increased （P<0.01）. Moreover， the structure of colonic mucosa was destroyed and inflammatory cells infiltrated in the model group. Compared with model group， body weight， colon length and IL-10 content in each dose group of Xielitang were significantly increased （P<0.05， P<0.01）， DAI score， intestinal weight index and CMDI score， IL-6 and TNF-α contents， mRNA and protein expression levels of TLR4， NF-κB and HIF-1α were notably decreased （P<0.05， P<0.01）. The pathological injury of colon was obviously alleviated. ConclusionXielitang can significantly improve the inflammatory response of UC mice induced by DSS， and its mechanism may be related to the regulation of TLR4/NF-κB/HIF-1α signaling pathway.