Objective To investigate relationship between hypoxia microenvironment and occurrence and development of hepatocellular carcinoma (HCC). Method The relevant literatures on researches of the relationship between the hypoxic microenvironment and the HCC were review and analyzed. Results The hypoxia microenvironment played an important role in inducing the drug resistance and angiogenesis of the HCC cells, and it was an important factor of affecting the ability of tumor metabolism, invasion, and migration. The hypoxia microenvironment could up-regulate the expression of hypoxia-inducible factors (HIFs) and promote its transcriptional activity, promote the expression of the vascular endothelial growth factor gene, and regulate the neovascularization in the tumor. Among them, the HIF-1α played a major role in regulating the angiogenesis, immune escape, tumor invasion and metastasis-related gene expression, participating in the glycolysis, regulating lysyl oxidase 2 and thus regulated epithelial-mesenchymal transition, then promoted the invasion and metastasis of the HCC; HIF-2α was a key regulator of the malignant phenotype involving in the cell proliferation, angiogenesis, apoptosis, metabolism, metastasis, and resistance to chemotherapy. The hypoxia microenvironment posed some difficulties for the treatment of HCC, but it was also a potential therapeutic breakthrough. Conclusion Hypoxia microenvironment can promote invasion and metastasis of HCC through various mechanisms, which provides new targets and strategies for clinical treatment of HCC.
Objective： To observe the effect of estrogen on the expr ession of pigment epithelium derived factor (PEDF) in cultured retinal Muuml;ller cells under the anoxic condition． Methods：After the anoxic retinal Muuml;ll er cells were tre ated with estrogen (E2) with the concentration of 10-6、10-5 and 10-7 mmol/L, t he level of expression of PEDF mRNA and the protein was detected by reverse tran scriptionpolymerase chain reaction and Western blotting analysis. Results：Th e expression of PEDF mRNA and protein decreased 24 hours after anoxia. E2 with t he concentration of 10-5 and 10-6 mmol/L inhibited the decrease of expression of PEDF mRNA and protein induced by anoxia, which related to the concentration of E2． Conclusion：strogen can regulate the expression of PEDF, which ma y play an important role in the regulation of retinal neovascularization．
ObjectiveTo investigate the effects of hypoxia inducible factor 1α (HIF-1α) overexpression on the differentiation of stem cells derived from human exfoliated deciduous teeth (SHED) into vascular endothelial cells.MethodsSHED was isolated from the retained primary teeth donated by healthy children by using collagenase digestion method. The third generation cells were identified by flow cytometry and alizarin red and alkaline phosphatase (ALP) staining after osteogenic differentiation culture. The SHED were divided into blank control group (SHED without any treatment), empty group (SHED infected with empty lentivirus), HIF-1α overexpression group (SHED infected with HIF-1α overexpression lentivirus), Wnt inhibitor group (SHED interfered by IWR-1), and combination group (HIF-1α overexpressed SHED interfered by IWR-1). Real-time fluorescence quantitative PCR (qRT-PCR) and Western blot were used to analyze the expressions of HIF-1α mRNA and protein in the SHED of blank control group, empty group, and HIF-1α overexpression group. Then the SHED in 5 groups were induced differentiation into vascular endothelial cells for 14 days. The expressions of cell surface marker molecule [von Willebrand factor (vWF) and CD31] were detected by flow cytometry. The mRNA expressions of vascular cell adhesion protein 1 (VCAM-1), KDR (Kinase-inserted domain containing receptor), and VE-cadherin (VE) were analyzed by qRT-PCR. The protein expressions of phosphate-glycogen synthasc kinase 3β (p-GSK3β) and β-catenin were analyzed by Western blot. The tube forming ability of induced cells was detected by Matrigel tube forming experiment. The ability of endothelial cells to phagocytic lipid after differentiation was detected by DiI-labeled acetylated low density lipoprotein (DiI-Ac-LDL) phagocytosis.ResultsAfter identification, the cells were SHED. After lentivirus transfection, compared with the blank control group and the empty group, the expressions of HIF-1α mRNA and protein in the HIF-1α overexpression group increased significantly (P<0.05). Compared with the blank control group and the empty group, the expressions of VCAM-1, KDR, and VE mRNA, the percentages of vWF positive cells and CD31 positive cells, and the relative expression of β-catenin protein were significantly higher (P<0.05), the relative expression of p-GSK3β protein was significantly lower (P<0.05), the number of tubules formed and the ability to phagocytic lipids significantly increased (P<0.05) in the HIF-1α overexpression group; while the indicators in the Wnt inhibitor group were opposite to those in the HIF-1α overexpression group (P<0.05). Compared with the HIF-1α overexpression group, the expressions of VCAM-1, KDR, and VE mRNA, the percentages of vWF positive cells and CD31 positive cells, and the relative expression of β-catenin protein were significantly lower (P<0.05), the relative expression of p-GSK3β protein was significantly higher, and the number of tubules formed and the ability of phagocytosis of lipids significantly reduced, showing significant differences between groups (P<0.05).ConclusionOverexpression of HIF-1α can promote SHED to differentiate into vascular endothelial cells by activating Wnt/β-catenin signaling pathway.
ObjectiveTo investigate the expression and significance of CD73 in rats with intermittent hypoxia and high fat diet.MethodsThe rat model of chronic intermittent hypoxia combined with high fat diet was established. Twenty-four healthy male Wistar rats in the SPF level were randomly divided into 4 group, with 6 rats in each group, namely group A (normoxia and normal diet), group B (normoxia and high fat diet), group C (intermittent hypoxia and normal diet)and group D (intermittent hypoxia and high-fat diet). After 6 weeks of experiment, the serum lipid levels, myocardial morphological changes under microscope, the expression level of CD73 protein detected byimmunohistochemistry and Western blot in myocardial cells in rats were compared among these groups.ResultsThe serum lipid levels were significantly different among these groups (P<0.05). HE results showed that the myocardial cells of group A had no obvious abnormalities; disorganized visible myocardial fibers with focal necrosis in groups B and C; myocardial cell injury was most obvious in group D, in which visible muscle fibers arranged in disorder, and grain was not clear, part of the muscle fibers were dissolved predominantly. Compared with group A, CD73 protein expression levels in myocardial cells in groups B, C, and D were significantly elevated (P<0.01). Furthermore, CD73 protein expression level in myocardial cells in group D was significantly higher than those in groups B and C (P<0.01). Western blot showed consistent results as immunohistochemistry: compared with group A, CD73 protein expression levels in groups B, C, and D were significantly elevated (P<0.05), and CD73 protein expression level in myocardial cells in group D was significantly higher than those in groups B and C (P<0.01).ConclusionChronic intermittent hypoxia and high fat diet can cause myocardial cell damage and upregulate CD73 expression in the cardiomyocytes.
Objective To summarize the advance of bioenergetic metabolic mechanisms of cancer cell. Methods Literatures about the recent studies on the bioenergetic metabolic mechanisms of cancer cell were reviewed.Results Cancer cells required a steady source of metabolic energy in order to continue their uncontrolled growth and proliferation. Accelerated uptake of glucose and glycolysis was one of the biochemical characteristics of hypoxia cancer cells. Glucose transport and metabolism were essential for the survival of tumor cells, leading to poor prognosis. Conclusions The studies on relationships between hypoxia-inducible genes and cancer have come a new understanding of the bioenergetic metabolic mechanisms of cancer cell, become new and important supplementary means of diagnosis and treatment of cancer, and enhanced existing strategies so that the treatment could be more rationally applied and personalized for cancer patients.
With the surged prevalence of myopia, the pathogenic mechanism underlying myopia has attracted attention. At present, it is generally believed in the flied that the reduced blood perfusion in the choroid is crucial for myopigenesis. Then, in the process of myopigenesis, how are the blurred visual signals transmitted to the choroidal blood vessels through the retina and retinal pigment epithelium, leading to the reduced choroidal blood perfusion. The cellular and molecular mechanisms underpinning this process remain elusive. In recent years, the theory of scleral hypoxia has attracted much attention. Popular signaling molecules in current research include dopamine, epidermal growth factor, retinoic acid, cholinergic molecules and adenosine, etc. These factors are likely to participate in signal transduction in retina and RPE, thus causing changes in choroidal blood flow and affecting the occurrence and development of myopia. Therefore, these signaling factors and their downstream pathways may provide new ideas for the prevention and control of myopia targets.
Objective To explore the difference between the hemorheology levels and the expression of hypoxia inducible factor 1α/2α (HIF-1α/2α) in the peripheral blood mononuclear cells of the Tibetan and Han patients with obstructive sleep apnea hypopnea syndrome (OSAHS). Methods This research recruited 30 high-risk Tibetan and Han patients with OSAHS, and 30 Tibetan and Han healthy volunteers at the same period. The whole blood viscometer was used to detect the high shear rate of whole blood viscosity, low shear rate of whole blood viscosity, plasma viscosity ratio, red blood cell aggregation index, and hematocrit in each group. RT-qPCR and Western blot assays were used to detect the mRNA and protein levels of phosphoinositide 3-kinase (PI3K), serine/threonine kinase (AKT), nuclear factor-κB (NF-κB) p65, HIF-1α and HIF-2α in peripheral blood mononuclear cells. Results The hemorheology level of Tibetan OSAHS patients was significantly higher than that of healthy Tibetans and Han OSAHS patients (P<0.05), and the hemorheology level of Han OSAHS patients was significantly higher than that of Han healthy people (P<0.05) . The mRNA and protein levels of PI3K, AKT, NF-κB p65 and HIF-1α in the peripheral blood mononuclear cells of Tibetan OSAHS patients were significantly higher than those of the healthy Tibetans or Han people, and these indexes of the Han OSAHS patients were significantly higher than those of the Han healthy people (all P<0.05), while HIF-2α mRNA and protein levels were significantly lower than those of healthy Han people (all P<0.05). Conclusion The upregulation of HIF-1α level and downregulation of HIF-2α expression in peripheral blood mononuclear cells of OSAHS patients depend on the activation of the PI3K/AKT/NF-κB p65 signaling pathway, and the hemorheological level of Tibetan OSAHS patients is higher than that of Han OSAHS patients.
ObjectiveTo explore the effects of hypoxia inducible factor-1 alpha (HIF-1α) on the reverse differentiation of hepatocellular carcinoma cells into liver cancer stem cells, and the maintenance of malignant biological behavior in hypoxic environment.MethodsCD133-negative cells in HepG2 cells were separated by immunomagnetic beads and divided into two groups. The cells of siRNA group were transfected with siRNA-HIF-1α to silence the expression of HIF-1α gene, while cells of the blank control group did not transfect any siRNA fragments. The two groups of cells were cultured under normal and hypoxic conditions respectively. MTT, cloning and Transwell chamber experiments were used to detect the proliferation and invasion ability of cells. Western blot and real-time PCR (RT-PCR) were used to detect the expressions of HIF-1α, CD133, CD90, and CD44 protein and mRNA in cells.ResultsMTT results showed that the cell proliferation rate increased with the prolongation of hypoxia in four groups. Compared with the blank control group at 24, 32, 40, and 48 hours, the cell proliferation rate decreased significantly after siRNA-HIF-1a transfection, on both two kinds of cultured conditions (P<0.05). The results of plate cloning experiment showed that the number of cell-forming clones increased significantly after hypoxic culture (there were significant differences between the transfected normoxic group and transfected hypoxic group, blank control normoxic group and blank control hypoxic group, P<0.05); and the formation of transfected hypoxic condition group at the same time of hypoxia was also significant (P<0.05). The number of clones were significantly less than that of the blank control group at the hypoxic condition (P<0.05). Transwell lab experiment showed that after hypoxic culture, the number of cells migrated to the inferior chamber in the transfection group was significantly reduced compared with that of the blank control group (P<0.05). Western blot and RT-PCR results showed that the expression levels of HIF-1α protein and tumor stem cell markers (CD133, CD90, and CD44 protein) in the blank control hypoxic condition group were significantly higher than those in the other three groups (P<0.05); after siRNA-HIF-1a transfection, HIF-1α mRNA and tumor stem cell markers mRNA (CD133, CD90, and CD44 mRNA) in the transfected hypoxic condition group were significantly lower than those in the transfected normal condition group and the blank control normal condition group (P<0.05).ConclusionsIn hypoxia environment, HIF-1α can promote hepatocellular carcinoma cells to differentiate into liver cancer stem cells and enhance their malignant biological behavior.
Objective To explore the mechanism of chronic intermittent hypoxia (CIH) on renal damage with normal diet and high-fat diet. Methods Twenty-four healthy male Wistar rats of SPF grade were randomly divided into 4 groups (n=6 in each group), namely group A (normoxia and common diet), group B (normoxia and high fat diet), Group C (CIH and common diet), and group D (CIH and high fat diet). The serum cystatin C (Cys-C) was measured and the renal CHOP protein was detected by immunohistochemistry. The ultrastructural changes of glomeruli and renal tubules were observed under electron microscope. Results The levels of Cys-C in group B, group C and group D were significantly higher than those in group A (P<0.05). The mean density of endoplasmic reticulum stress (ERS) marker protein CHOP in group B, group C and group D was significantly higher than that in group A (P<0.05). Electron microscope revealed focal nuclear pyknosis in the partly renal tubular epithelial cells, sparse and scattered brush border in group B and group C, also revealed nuclear pyknosis in a large number of tubular epithelial cells, sparse and scattered brush border in group D. Conclusion CIH can activate the ERS mediated renal tubular epithelial apoptosis, thus induce ultrastructure changes and damage of kidney.
Objective To investigate the effect of angiopoietin-like protein 3 (ANGPTL3) on lipid metabolism in patients with obstructive sleep apnea (OSA). Methods A total of 59 OSA patients and 20 healthy controls from the First Affiliated Hospital of Zhengzhou University between May 2023 and February 2024 were included in the study. All participants underwent overnight polysomnography (PSG). Based on the apnea-hypopnea index (AHI), the OSA patients were divided into a mild group and a moderate-to-severe group. Morning blood samples were collected after an 8-hour fast to measure lipid profiles and ANGPTL3 levels. Statistical analyses were performed using SPSS 25.0 software. Results The levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and ANGPTL3 were significantly higher, while high-density lipoprotein cholesterol (HDL-C) was significantly lower in the OSA group compared with the control group (P<0.05). ANGPTL3 level was higher in the moderate-to-severe OSA group than that in the mild OSA group and the control group, and higher in the mild OSA group than that in the control group (P<0.05). In the severe hypoxemia group, ANGPTL3 level was significantly higher than that in the mild-to-moderate hypoxemia group (P<0.05). The ANGPTL3 level was also significantly higher in the hyperlipidemia group compared wiht the non-hyperlipidemia group (P<0.05). In the OSA group, ANGPTL3 was positively correlated with TC, TG, percentage of cumulative time with oxygen saturation below 90% in total sleep time (T90) and oxygen desaturation index (ODI), and negatively correlated with lowest arterial oxygen saturation (LSaO2) and mean arterial oxygen saturation (MSaO2). After adjusting for relevant confounding factors, logistic regression analysis indicated that ANGPTL3 might be a potential independent risk factor for OSA, with an odds ratio of 1.021 (95%CI 1.002 - 1.040). Conclusions The level of ANGPTL3 is elevated in OSA patients. The elevation of blood lipid levels in OSA patients may be associated with chronic intermittent hypoxia-induced regulation of ANGPTL3 levels.