Expression Levels Of Hypoxia-inducible Factor-1α Research Articles

Protective effects of 2-methoxyestradiol against hypoxic pulmonary hypertension in neonatal rats

To investigate the protective effects of 2-methoxyestradiol (2ME) against hypoxic pulmonary hypertension (HPH) in neonatal rats. Ninety-six Wistar neonatal rats were randomly divided into a normoxia group, a hypoxia group, and a hypoxia + 2ME group, with each group further subdivided into 3-day, 7-day, 14-day, and 21-day subgroups, containing eight rats each. The hypoxia and hypoxia + 2ME groups received daily subcutaneous injections of saline and 2ME (240 μg/kg), respectively, while the normoxia group was raised in a normoxic environment with daily saline injections. Right ventricular systolic pressure (RVSP) was measured using the direct pressure method. Pulmonary vascular morphology was assessed using hematoxylin and eosin staining, with metrics including the percentage of medial thickness of small pulmonary arteries relative to the external diameter (MT%) and the cross-sectional area of the media of small pulmonary arteries relative to the total cross-sectional area (MA%). Immunohistochemistry was used to detect the expression levels of hypoxia-inducible factor-1α (HIF-1α) and proliferating cell nuclear antigen (PCNA) proteins, while real-time quantitative PCR was used to to assess HIF-1α and PCNA mRNA levels. Compared to the normoxia group, the hypoxia and hypoxia + 2ME groups showed increased RVSP and upregulated HIF-1α and PCNA protein and mRNA expression levels at 3, 7, 14, and 21 days after hypoxia (P<0.05). Furthermore, at 7, 14, and 21 days after hypoxia, the hypoxia group showed increased MT% and MA% (P<0.05). In comparison to the hypoxia group, the hypoxia + 2ME group exhibited reduced RVSP and downregulated HIF-1α and PCNA protein and mRNA expression levels, along with decreased MT% and MA% at 7, 14, and 21 days after hypoxia (P<0.05). 2ME may protect against HPH in neonatal rats by inhibiting the expression of HIF-1α and PCNA and reducing pulmonary vascular remodeling. Citation:Chinese Journal of Contemporary Pediatrics, 2024, 26(7): 757-764.

Morusin suppresses the stemness characteristics of gastric cancer cells induced by hypoxic microenvironment through inhibition of HIF-1α accumulation

Gastric cancer (GC) is a common, life-threatening malignancy that contributes to the global burden of cancer-related mortality, as conventional therapeutic modalities show limited effects on GC. Hence, it is critical to develop novel agents for GC therapy. Morusin, a typical prenylated flavonoid, possesses antitumor effects against various cancers. The present study aimed to demonstrate the inhibitory effect and mechanism of morusin on the stemness characteristics of human GC in vitro under hypoxia and to explore the potential molecular mechanisms. The effects of morusin on cell proliferation and cancer stem cell-like properties of the human GC cell lines SNU-1 and AGS were assessed by MTT assay, colony formation test, qRT-PCR, flow cytometry analysis, and sphere formation test under hypoxia or normoxia condition through in vitro assays. The potential molecular mechanisms underlying the effects of morusin on the stem-cell-like properties of human GC cells in vitro were investigated by qRT-PCR, western blotting assay, and immunofluorescence assay by evaluating the nuclear translocation and expression level of hypoxia-inducible factor-1α (HIF-1α). The results showed that morusin exerted growth inhibitory effects on SNU-1 and AGS cells under hypoxia in vitro. Moreover, the proportions of CD44+/CD24– cells and the sphere formation ability of SNU-1 and AGS reduced in a dose-dependent manner following morusin treatment. The expression levels of stem cell-related genes, namely Nanog, OCT4, SOX2, and HIF-1α, gradually decreased, and the nuclear translocation of the HIF-1α protein was apparently attenuated. HIF-1α overexpression partially reversed the abovementioned effects of morusin. Taken together, morusin could restrain stemness characteristics of GC cells by inhibiting HIF-1α accumulation and nuclear translocation and could serve as a promising compound for GC treatment.

Gene Expression of Glycolysis Enzymes in MCF-7 Breast Cancer Cells Exposed to Warburg Effect and Hypoxia.

Hypoxia can cause significant changes in the glucose metabolism of cancer cells that prefer aerobic glycolysis for energy production instead of the conventional oxidative phosphorylation mechanism. In this study, breast cancer cells (MCF-7) were exposed to glucose (0-5.5-15-55 mM), during specific incubation periods (3, 6, 12, or 24 hours) under normoxic and hypoxic conditions. The expression levels of hypoxia-inducible factor-1α (HIF-1α), glucose transporter-1 (GLUT-1), and glycolytic enzymes at varying glucose concentrations in cells were investigated in the different oxygen environments. It was determined that glycolytic enzymes [Hexokinase 2 (HK2), Pyruvate Kinase M2 (PKM2), Glucose-6-phosphate dehydrogenase (G6PD), Lactate Dehydrogenase A (LDHA), Glyceraldehyde-3-phosphate Dehydrogenase (GAPDH), and Phosphofructokinase M (PFKM)] increased at the transcriptional level, especially in the first hours. This increase indicates that major metabolic reprogramming in response to hypoxia probably occurs over a short period of time. The increase in G6PD gene expression under high glucose and hypoxia conditions suggests that the pentose phosphate pathway (PPP) is used by cancer cells to synthesize necessary precursors for the cell. The results of the study showed that there is a significant interaction between hypoxia and glycolytic metabolism in cancer cells. It is thought that metabolic pathways activated by hypoxia and related genes located in these pathways will contribute to the literature by offering the potential to be target molecules for therapeutic purposes.

Sirtuin4 alleviates severe acute pancreatitis by regulating HIF-1α/HO-1 mediated ferroptosis.

Acute pancreatitis (AP) is a common emergency of the digestive system and serious cases can develop into severe acute pancreatitis (SAP), which ortality rates up to 30%. Sirtuin4 (SIRT4) is a member of the sirtuin family, and plays a key role in inflammation and oxidative stress. However, the potential role of SIRT4 in SAP has yet to be elucidated. In the present study, we found that the expression level of SIRT4 in human AP was downregulated by screening a public database, suggesting that SIRT4 may play a role in AP. Subsequently, we used L-arginine (L-Arg) to induce SAP in SIRT4 knockout (SIRT4_KO) and SIRT4 overexpression (AAV_SIRT4) mice. The results showed that the pancreatic tissue injury and related lung and kidney injury were serious in SIRT4_KO mice after SAP induction, but were significantly reduced in AAV_SIRT4 mice. More importantly, we found that the levels of antioxidant factors GSH and SOD were decreased in SIRT4_KO mice, and the production of oxidative products and lipid peroxidation markers was increased, suggesting that SIRT4 was involved in inflammation and oxidative stress during SAP. Further studies showed that the absence or overexpression of SIRT4 affected the expression level of Hypoxia-inducible factor-1α (HIF-1α) after SAP induction, and regulated the expression of ferroptosis related proteins by mediating HIF-1α/HO-1 pathway. Collectively, our study revealed that SIRT4 plays a protective role in SAP by regulating the HIF-1α/HO-1 pathway to inhibit ferroptosis.

Prognostic Value of HIF-1α-Induced Genes in Sepsis/Septic Shock.

Hypoxia is characterized as one of the main consequences of sepsis, which is recognized as the leading cause of death in intensive care unit (ICU) patients. In this study, we aimed to examine whether the expression levels of genes regulated under hypoxia could be utilized as novel biomarkers for sepsis prognosis in ICU patients. Whole blood expression levels of hypoxia-inducible factor-1α (HIF1A), interferon-stimulated gene 15 (ISG15), hexokinase 2 (HK2), lactate dehydrogenase (LDHA), heme oxygenase-1 (HMOX1), erythropoietin (EPO), and the vascular endothelial growth factor A (VEGFA) were measured on ICU admission in 46 critically ill, initially non-septic patients. The patients were subsequently divided into two groups, based on the development of sepsis and septic shock (n = 25) or lack thereof (n = 21). HMOX1 mRNA expression was increased in patients who developed sepsis/septic shock compared to the non-septic group (p < 0.0001). The ROC curve, multivariate logistic regression, and Kaplan-Meier analysis demonstrated that HMOX1 expression could be utilized for sepsis and septic shock development probability. Overall, our results indicate that HMOX1 mRNA levels have the potential to be a valuable predictive factor for the prognosis of sepsis and septic shock in ICU patients.

Mechanism of Cistanches Herba in treatment of cancer-related fatigue based on network pharmacology and experimental verification

This study aimed to explore the mechanism of Cistanches Herba in the treatment of cancer-induced fatigue(CRF) by network pharmacology combined with in vivo and in vitro experiments to provide a theoretical basis for the clinical medication. The chemical constituents and targets of Cistanches Herba were searched from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP). The targets of CRF were screened out by GeneCards and NCBI. The common targets of traditional Chinese medicine and disease were selected to construct a protein-protein interaction(PPI) network, followed by Gene Ontology(GO) functional and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analyses. A visual signal pathway rela-ted to Chinese medicine and disease targets was constructed. The CRF model was induced by paclitaxel(PTX) in mice. Mice were divided into a control group, a PTX model group, and low-and high-dose Cistanches Herba extract groups(250 and 500 mg·kg~(-1)). The anti-CRF effect in mice was evaluated by open field test, tail suspension test, and exhaustive swimming time, and the pathological morphology of skeletal muscle was evaluated by hematoxylin-eosin(HE) staining. The cancer cachexia model in C2C12 muscle cells was induced by C26 co-culture, and the cells were divided into a control group, a conditioned medium model group, and low-, medium-, and high-dose Cistanches Herba extract groups(62.5, 125, and 250 μg·mL~(-1)). The reactive oxygen species(ROS) content in each group was detected by flow cytometry, and the intracellular mitochondrial status was evaluated by transmission electron microscopy. The protein expression levels of hypoxia-inducible factor-1α(HIF-1α), BNIP3L, and Beclin-1 were detected by Western blot. Six effective constituents were screened out from Cistanches Herba. The core genes of Cistanches Herba in treating CRF were AKT1, IL-6, VEGFA, CASP3, JUN, EGFR, MYC, EGF, MAPK1, PTGS2, MMP9, IL-1B, FOS, and IL10, and the pathways related to CRF were AGE-RAGE and HIF-1α. Through GO enrichment analysis, it was found that the main biological functions involved were lipid peroxidation, nutrient deficiency, chemical stress, oxidative stress, oxygen content, and other biological processes. The results of the in vivo experiment showed that Cistanches Herba extract could significantly improve skeletal muscle atrophy in mice to relieve CRF. The in vitro experiment showed that Cistanches Herba extract could significantly reduce the content of intracellular ROS, the percentage of mitochondrial fragmentation, and the protein expression of Beclin-1 and increase the number of autophagosomes and the protein expression of HIF-1α and BNIP3L. Cistanches Herba showed a good anti-CRF effect, and its mechanism may be related to the key target proteins in the HIF-1α signaling pathway.

The Efficacy of Radiation is Enhanced by Metformin and Hyperthermia Alone or Combined Against FSaII Fibrosarcoma in C3H Mice.

The effects of mild-temperature hyperthermia (MTH) and metformin, alone or in combination, on the efficacy of high-dose hypofractionated radiation against experimental tumors were investigated. FSaII fibrosarcoma grown subcutaneously in the hind legs of C3H mice was irradiated with a single 15 Gy dose using a 60Co irradiator. The radio frequency capacitive method was used to heat the tumors at 41.0°C for 30 min. Metformin was intraperitoneally (i.p.) administered daily to tumor-bearing mice at a dose of 150 mg/kg. The expression levels of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), and programmed cell death-ligand 1 (PD-L1) were determined by immunohistochemical staining of the excised tumor tissues. The apoptosis of tumor cells in vivo was quantified by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and cleaved caspase-3 staining of the excised tumor tissues. Irradiation of tumors markedly increased the expression of HIF-1α, VEGF, and PD-L1, and MTH and metformin used either alone or in combination significantly abrogated the radiation-induced upregulation of these proteins. MTH and metformin alone or combined increased the radiation-induced apoptosis in tumor cells and enhanced the radiation-induced suppression of tumor growth. The findings indicated that the increased tumor response to 15 Gy irradiation by MTH and metformin alone or in combination was due, in part, to the abrogation of the radiation-induced upregulation of HIF-1α and its downstream targets VEGF and PD-L1.

The protective effects of Azilsartan against hypoxia in endometrial stromal cells: an implication in endometriosis

IntroductionEndometriosis is a reproductive disorder closely associated with hypoxia stress. Increasing evidences have implied the important roles of angiotensin II (ANG II) receptors in the pathophysiology of endometriosis. Thus, we speculated that Azilsartan (AZL), an ANG II receptor blocker, might have an effective function in controlling endometriosis.Material and methodsThe endometriotic animal model was established in female SD rats (6-8 weeks old, 200-220 g). Rats were divided into sham group and endometriosis (EMS) group. Rats in EMS group were anaesthetized by halothane and a mid-ventral incision was performed to expose the bowels. Human endometrial stromal cell line T-HESC was used for the in vitro assays. The T-HESC cells were cultured in DMEM-F12 mediumwith 10% fetal bovine serum (FBS, Hyclone), and 4 mM L-glutamine, 0.25% HEPES plus necessary antibiotics (Sigma-Aldrich, USA), at 37°C in a humidified atmosphere of 5% CO2.ResultsThe results show that upregulation of ANG II type 1 (AT1) receptor was observed in the endometriotic rat models. Treatment with AZL prevented the development of endometriotic lesions and suppressed the expressions of HIF-1α and cyclooxygenase 2 (COX-2) in endometriotic rats. In vitro assays proved that hypoxia-induced proliferation, migration, and invasion of T-HESC cells were attenuated by AZL. AZL inhibited the expression levels of hypoxia-inducible factor-1α (HIF-1α), COX-2, and prostaglandin E2 (PGE2) production in hypoxia-induced T-HESC cells. Overexpression of HIF-1α blocked the effects of AZL on T-HESC cells in response to hypoxia.ConclusionsAZL showed therapeutic function on endometriosis through inhibiting hypoxia-induced cell proliferation, migration, and invasion of T-HESC cells via HIF-1α/COX-2/PGE2 signaling.

Hypoxia‑induced mitophagy regulates proliferation, migration and odontoblastic differentiation of humandental pulp cells through FUN14 domain‑containing 1.

FUN14 domain-containing 1 (FUNDC1) is a receptor that has been previously reported to activate hypoxia-induced mitophagy. However, the potential role of FUNDC1 in the pathophysiology of dental pulp diseases remains unknown. Therefore, present study first collected tissue specimens from patients with pulpitis and from healthy individuals. The results of reverse transcription-quantitative PCR and immunohistochemical staining revealed markedly increased FUNDC1 and hypoxia-inducible factor-1α expression in pulpitis tissue specimens compared with those from healthy individuals. To provide a theoretical basis for the study of the occurrence, development and reparative mechanisms in the dental pulp after tissue injury, the present study then investigated the role of hypoxia-induced mitophagy in the regulation of proliferation, migration and odontoblastic differentiation in human dental pulp cells (HDPCs), in addition, to the possible involvement of FUNDC1. The surface markers and multipotent differentiation capabilities of HDPCs were performed by flow cytometry (surface markers), alizarin red (osteogenic capabilities), alcian blue (chondrogenic capabilities) and oil red O (adipogenic capabilities). Following culture under hypoxia conditions (1% O2) for varying time periods, the proliferation, migration and odontoblastic differentiation of HDPCs were measured using Cell Counting Kit-8, wound healing and Transwell migration assays, alkaline phosphatase staining and activity tests and western blotting (runt-related transcription factor 2, collagen I, osterix and osteopontin), respectively. Immunofluorescence and western blotting were performed to measure the expression levels of hypoxia-inducible factor-1α, pro-fission dynamin-related protein 1, mitochondria-related proteins translocase of inner mitochondrial membrane 23 and translocase of outer mitochondrial membrane 20, in addition to those of autophagy markers (p62, LC3II, Beclin-1 and autophagy-related 5). Transmission electron microscopy was also used to image the autophagosomes and mitochondrial morphology. In addition, to study the functional role of FUNDC1, its expression was silenced by liposome-mediated transfection with small interfering RNA into HDPCs. Compared with those in HDPCs cultured under normoxic conditions (21% O2), the ability of autophagy in HDPCs cultured under hypoxic conditions for 18 h was markedly increased, whilst the proliferation, migration and odontoblastic differentiation were also enhanced. Increased numbers of autophagosomes could also be observed in the hypoxic group. However, FUNDC1 knockdown in HDPCs reversed the aforementioned effects. Overall, data from the present study suggest that hypoxia can promote the proliferation, migration and odontoblastic differentiation of HDPCs, where the underlying mechanism may be associated with the activation of mitophagy downstream of FUNDC1.

Semaphorin 3A attenuates the hypoxia suppression of osteogenesis in periodontal ligament stem cells.

The occurrence and development of periodontitis are closely related to hypoxia of the periodontal microenvironment. Periodontal ligament stem cells (PDLSCs) are considered to have potential to regenerate periodontal tissues. Semaphorin 3A (Sema3A) plays an essential role in promoting osteogenesis. However, the effect of Sema3A on osteogenesis of PDLSCs under hypoxia remains unclear. The aim of this study was to investigate the effect of Sema3A on osteogenesis of PDLSCs under hypoxia. Isolated PDLSCs were identified using flow cytometry. Adipogenic differentiation potential was identified by oil red O staining. Osteogenesis was measured using Alizarin Red S staining and ALP staining. Intracellular hypoxia was induced using cobalt chloride (CoCl2 ). The expression level of hypoxia-inducible factor-1α (HIF-1α) was detected via ELISA. Expression of osteogenic markers and Sema3A was analyzed using western blot and real-time PCR. The proliferation and osteogenesis of PDLSCs were markedly inhibited with increased concentrations of CoCl2 . Under the treatment with a low concentration of CoCl2 , expression of related osteogenic markers and Sema3A decreased in a time-dependent manner. ARS and ALP staining results also showed that osteogenic calcification decreased under hypoxia. Apigenin, an inhibitor of HIF-1α, effectively up-regulated expression of Sema3A and osteogenic markers with CoCl2 treatment. Moreover, exogenous Sema3A significantly increased the expression of osteogenesis-related markers and mineralization of PDLSCs according to ALP and ARS staining with CoCl2 treatment. Hypoxia markedly inhibited osteogenesis of PDLSCs. Sema3A explicitly attenuated the hypoxia suppression of osteogenesis in PDLSCs.

Vascular characteristics and expression of hypoxia genes in Tibetan pigs' hearts.

BackgroundTibetan pigs have exhibited unique characteristics from low‐altitudes pigs and adapted well to the Qinghai‐Tibet Plateau.ObjectivesThe current study was undertaken to investigate the hypoxic adaptation of heart in Tibetan pigs.MethodsThe hearts of Tibetan pigs and Landrace pigs raised at high or low altitudes were compared using 3D casting technology, scanning electron microscopy and real‐time quantitative PCR (qRT‐PCR).ResultsWe found that the ratio of the major axis to the minor axis and the density of the heart were significantly higher in Tibetan pigs than in Landrace pigs (p < 0.05). Tibetan pigs had larger diameters and higher densities of arterioles than Landrace pigs (p < 0.05), and these features have a similar variation with the expression of vascular endothelial growth factor (VEGF). The cardiac expression levels of hypoxia‐inducible factor‐1α (HIF‐1α) and endothelial nitric oxide synthase (eNOS) were significantly higher in pigs reared at high altitudes than in those reared at low altitudes (p < 0.05). In contrast, Egl nine homolog 1 (EGLN1) had the opposite trend with respect to HIF‐1α and eNOS and was related to red blood cell (RBC) counts. Notably, the expressions of erythropoietin (EPO) and endothelial PAS domain‐containing protein 1 (EPAS1) were significantly higher in Landrace pigs kept at high altitudes than in the others (p < 0.05) and were associated with haemoglobin.ConclusionsThese findings show that the regulation of the heart function of Tibetan pigs in a hypoxic environment is manifested at various levels to ensure the circulation of blood under extreme environmental conditions.

Molecular mechanism of zoledronic acid inhibiting angiogenesis by semi flexible binding with vascular endothelial growth factor conformation

Objective: To study the relationship between zoledronic acid (ZOL) and vascular endothelial growth factor (VEGF) conformation so as to reveal the mechanism of bisphosphonates inhibiting angiogenesis. Methods: The binding structures of ZOL and VEGF were preprocessed and the molecular dockings were simulated through AutoDockTools, Discovery studio4 and AutoDockVina. The best binding conformation was accurately screened. The effects of various concentrations of ZOL (group A was 0 μmol/L, groups B, C and D were 25, 50 and 100 μmol/L, respectively) on human umbilical vein endothelial cell (HUVEC) proliferation, angiogenesis and angiogenic molecules were detected by using cell counting kit-8 (CCK-8) in vivo and in vitro angiogenesis, immunofluorescence and Western blotting. Results: There was a ZOL binding site on the target protein VEGF conformation. The affinity was -5.2 kcal/mol. This binding site consisted of the hydrophobic region composed of amino acids Cys26, 51, 57, etc. and the hydrogen bond binding region of the A chain (ASP34, SER50) and B chain (CYS61, 68, LEU66, GLY59). The results of CCK-8 showed that the levels of value A in groups B, C and D were significantly lower than that in group A at each time point from 3 to 6 days (P<0.05). In vitro vascular experiments demonstrated that the numbers of budding in groups B, C and D [(208±28), (151±21) and (62±9), respectively] were significantly lower than that in group A (276±30) (P<0.05). In vivo vascular experiments displayed that the ratio of Matrigel gel/plasma fluorescence in group A (0.003 1±0.000 3) was significantly higher than those in group B (0.002 1±0.000 2), group C (0.001 6±0.000 2) and group D (0.000 6±0.000 1) (P<0.05). The results of Western blotting revealed that the expression of VEGF in groups B, C and D [(0.72±0.11), (0.41±0.07) and (0.24±0.04), respectively] were significantly lower than that in group A (1.01±0.02) (P<0.05), and the expression levels of hypoxia-inducible factor-1α (HIF-1α) in groups B, C and D [(0.68±0.09), (0.55±0.06) and (0.43±0.08), respectively] were significantly lower than that in group A (0.96±0.04) (P<0.05). Conclusions: ZOL could inhibit cell proliferation, in vivo and in vitro vascularization and expression of VEGF/HIF-1α. The binding site of ZOL with the conformation of VEGF was located in the hydrophobic region and hydrogen-bonding region of amino acids. Designing an antagonist targeting this site might potentially alleviate the effect of ZOL in inhibiting angiogenesis.

NF-kappa B interacting long noncoding RNA enhances the Warburg effect and angiogenesis and is associated with decreased survival of patients with gliomas

In various malignant tumors, NF-kappa B interacting long noncoding RNA (NKILA) displays antitumor activity by inhibiting the NF-kappa B pathway. However, the role of NKILA in gliomas remains unclear. Surprisingly, this study showed that NKILA is significantly upregulated in gliomas, and the increased levels of NKILA were correlated with a decrease in patient survival time. NKILA increased the expression level of hypoxia-inducible factor-1α, and the activity of the hypoxia pathway in gliomas. Furthermore, we demonstrated that NKILA enhances the Warburg effect and angiogenesis in gliomas both in vitro and in vivo. Therefore, NKILA is a potential therapeutic target in gliomas. In addition, we showed that a 20(S)-Rg3 monomer suppresses NKILA accumulation and reverses its stimulation of the Warburg effect and angiogenesis in gliomas, both in vitro and in vivo. Therefore, this study not only identified NKILA as a potential therapeutic target in gliomas, but also demonstrated a practical approach to treatment.

Latifolin protects against myocardial infarction by alleviating myocardial inflammatory via the HIF-1α/NF-κB/IL-6 pathway

Context The Traditional Chinese herb medicine Dalbergia odorifera T. Chen (Fabaceae), exerted a protective effect on myocardial ischaemia. Latifolin is a neoflavonoid extracted from Dalbergia odorifera. It has been reported to have the effects of anti-inflammation and cardiomyocyte protection. Objective To investigate whether latifolin can improve myocardial infarction (MI) through attenuating myocardial inflammatory and to explore its possible mechanisms. Materials and methods Left coronary artery was ligated to induce a rat model of MI, and the rats were treated with sodium carboxymethyl cellulose (CMC-Na) or different doses of latifolin (25, 50, 100 mg/kg/d) by oral gavage for 28 days. Serum contents of myocardial enzyme were measured at seven and fourteen days after treatment. Cardiac function, infarct size, histopathological changes and inflammatory cells infiltration was assessed at 28 days after treatment. Western blotting was used to investigate the underlying mechanisms. Results Latifolin treatment markedly decreased the contents of myocardial enzymes, and increased left ventricular ejection fraction (85.27% vs. 59.11%) and left ventricular fractional shortening (62.71% vs. 45.53%). Latifolin was found to significantly reduced infarction size (27.78% vs. 39.07%), myocardial fibrosis and the numbers of macrophage infiltration (436 cells/mm2 vs. 690 cells/mm2). In addition, latifolin down-regulated the expression levels of hypoxia-inducible factor-1α (0.95-fold), phospho-nuclear factor-κB (0.2-fold) and interleukin-6 (1.11-fold). Discussion and conclusions Latifolin can protect against myocardial infarction by improving myocardial inflammation through the HIF-1α/NF-κB/IL-6 signalling pathway. Accordingly, latifolin may be a promising drug for pharmacological treatment of ischaemic cardiovascular disease.

Radiosensitizing effects of Cyclocaryapaliurus polysaccharide on hypoxic A549 and H520 human non-small cell lung carcinoma cells.

Cyclocarya paliurus (CP) polysaccharide (CPP) is a chemical component contained in CP, which has been reported to possess significant hypoglycemic activity. The present study aimed to investigate the radiosensitizing effect and underlying mechanisms of CPP on hypoxic A549 and H520 human non-small cell lung carcinoma cells. Cell viability, apoptosis and proliferation were determined using Cell Counting kit-8 assay, flow cytometry and colony formation assay, respectively. mRNA and protein expression levels were determined by reverse transcription-quantitative PCR and western blot analysis, respectively. The results suggested that CPP markedly inhibited the viability of hypoxic A549 and H520 cells. In response to combined treatment with CPP and radiation, hypoxic A549 and H520 cells exhibited enhanced apoptosis; in addition, cell proliferation was suppressed and the expression levels of hypoxia-inducible factor-1α, survivin and cleaved caspase-3 were modified. Furthermore, CPP in combination with radiation affected the mammalian target of rapamycin (mTOR)/Akt/phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) pathway. These findings indicated that CPP may enhance the radiosensitivity of hypoxic A549 and H520 cells; this effect may be associated with inhibition of the mTOR/Akt/PI3K pathway. The potential radiosensitizing effects of CPP on hypoxic A549 and H520 cells suggested that CPP may be an effective target for treatment of non-small cell lung carcinoma.

Hypoxia-induced epithelial-mesenchymal transition and fibrosis for the development of breast capsular contracture

Fibrosis has been considered as a major cause of capsular contracture. Hypoxia has widely emerged as one of the driving factors for fibrotic diseases. The aim of this study was to examine the association between hypoxia-induced fibrosis and breast capsular contracture formation. Fibrosis, epithelial-mesenchymal transition (EMT), expression levels of hypoxia-inducible factor-1α (HIF-1α), vimentin, fibronectin, and matrix metalloproteinase-9 (MMP-9) in tissues from patients with capsular contracture were determined according to the Baker classification system. Normal breast skin cells in patients with capsular contracture after implant-based breast surgery and NIH3T3 mouse fibroblasts were cultured with cobalt chloride (CoCl2) to mimic hypoxic conditions. Treatment responses were determined by detecting the expression of HIF-1α, vimentin, fibronectin, N-cadherin, snail, twist, occludin, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1) and -2, as well as phosphorylated ERK. The expression levels of HIF-1α, vimentin, fibronectin, and fibrosis as well as EMT were positively correlated with the severity of capsular contracture. MMP-9 expression was negatively correlated the Baker score. Hypoxia up-regulated the expression of HIF-1α, vimentin, fibronectin, N-cadherin, snail, twist, TIMP-1 and -2, as well as phosphorylated ERK in normal breast skin cells and NIH3T3. Nonetheless, the expression levels of MMP-9 and occludin were down-regulated in response to CoCl2 treatment. This study is the first to demonstrate the association of hypoxia-induced fibrosis and capsular contracture.

Effects and significance of formononetin on expression levels of HIF-1α and VEGF in mouse cervical cancer tissue.

Effects and significance of formononetin on the expression levels of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in mouse cervical cancer tissue were investigated. The animal models of Balb/c nude mice with cervical cancer were established by the inoculation of HeLa cells, and randomly divided into positive control (n=10), cisplatin (n=15) and formononetin group (n=15). Mice were all sacrificed on the 31st day after administration, and their tumors were excised and weighed to calculate tumor inhibition rate. At the same time, their cancer tissues were obtained. RT-qPCR was used for detecting the mRNA expression levels of HIF-1α and VEGF, and western blotting for detecting the protein expression levels. During the medication intervention, mice in the formononetin group had no obvious adverse reactions, and were in good condition, whereas mice in the cisplatin group had poor appetite, drooping spirits and decreased activity. Mice in the cisplatin and the formononetin groups had significantly lower tumor mass and volume than those in the positive control group (P<0.05). The tumor inhibition rate of mice was 56.24% in the cisplatin group, and 50.17% in the formononetin group. Cervical cancer mice in the formononetin and the cisplatin groups had significantly lower mRNA and protein expression levels of HIF-1α and VEGF in tissues than those in the positive control group (P<0.05). Formononetin can inhibit the growth of cervical cancer and reduce the mRNA and protein expression levels of HIF-1α and VEGF in mouse cervical cancer. Formononetin has an inhibitory effect on cervical cancer tumors similar to that of cisplatin, but the former has smaller side effects, providing data for the clinical use in cervical cancer.

Clinicopathological significance and prognostic implication of nuclear factor-κB activation in colorectal cancer

ObjectiveThe aim of the present study was to evaluate the clinicopathological significance of phosphorylated nuclear factor-κB (pNF-κB) expression, and its impact on epithelial–mesenchymal transition and angiogenesis in colorectal cancer (CRC). MethodsWe carried out immunohistochemistry of pNF-κB on 261 human CRC tissues, and evaluated nuclear expression, regardless of cytoplasmic expression. We also investigated the correlation between pNF-κB expression and clinicopathological characteristics, survival, and epithelial–mesenchymal transition and angiogenesis-related markers in CRC. ResultspNF-κB was expressed in the nuclei of 164 of the 261 CRC tissues (62.8%). Furthermore, pNF-κB was significantly correlated with frequent perineural invasion, lymph node metastasis, and higher pTNM stage. However, there was no significant correlation between pNF-κB expression and other clinicopathological parameters. Among the epithelial–mesenchymal transition markers examined, SNAIL expression was significantly correlated with pNF-κB expression (P = 0.001) but E-cadherin expression was not. CRC with pNF-κB expression had significantly higher SIRT1 expression levels and hypoxia-inducible factor-1α expression levels than CRC without pNF-κB expression (P < 0.001 and P < 0.001, respectively). However, there was no correlation between the expression levels of pNF-κB and VEGF. pNF-κB expression was significantly correlated with worse overall and recurrence-free survival rates (P < 0.001 and P < 0.001, respectively). ConclusionpNF-κB expression was significantly correlated with aggressive tumor behaviors and worse survival rates. Furthermore, pNF-κB expression may affect tumor invasion and progression through SNAIL-related epithelial–mesenchymal transition and SIRT1- and hypoxia-inducible factor-1α-induced angiogenesis.

Relationships between expression of hypoxia-inducible factor-1α protein and clinicopathological characte-ristics and prognosis of patients with gastric cancer

Objective To investigate the expression level of hypoxia-inducible factor-1α (HIF-1α) in gastric cancer and its relationship with clinicopathological characteristics and prognosis of patients with gastric cancer. Methods From March 3, 2011 to September 28, 2012, 49 patients with gastric adenocarcinoma tissue chips were selected from pathology department of our hospital. They were matched with paracancerous tissues. The expression levels of HIF-1α were measured by immunohistochemistry method in gastric cancer tissues and paracancerous tissues chips. Kaplan-Meier was used to evaluate the progression-free survival (PFS) and overall survival (OS), and the Cox proportional hazards model was used to analyze whether HIF-1α was a prognostic factor. Results The high expression rate of HIF-1α protein in gastric cancer was significantly higher than that in paired para-carcinoma group (42.9% vs. 4.1%, χ2=20.509, P<0.001). The expression of HIF-1α protein was related to TNM stage (χ2=4.601, P=0.032), vascular invasion (χ2=6.766, P=0.009) and degree of differentiation (χ2=7.969, P=0.005). Compared with patients with low expression of HIF-1α, the median PFS (16.2 months vs. 27.3 months) and median OS (34.8 months vs. 43.8 months) were shorter in the patients with high expression of HIF-1α, and the differences were statistically significant (median PFS: χ2=4.661, P=0.002; median OS: χ2=6.903, P=0.009). The results of single factor analysis showed that overexpre-ssion of HIF-1α was correlated with PFS and OS (PFS: HR=4.461, 95%CI: 1.969-10.802, P<0.001; OS: HR=3.109, 95%CI: 1.274-7.588, P=0.013). The results of Cox multivariate analysis showed that overexpression of HIF-1α was the independent risk factor that affected the survival and prognosis of patients with gastric cancer (PFS: HR=4.747, 95%CI: 2.175-10.230, P<0.001; OS: HR=3.171, 95%CI: 1.358-7.404, P=0.008). Conclusion The high expression rate of HIF-1α protein in gastric cancer tissues is significantly higher than that in paracancerous tissues. The expression of HIF-1α is associated with TNM stage, vascular invasion, degree of differentiation in patients with gastric cancer. The high expression of HIF-1α is associa-ted with the shorter median OS and PFS. The high expression of HIF-1α is an independent risk factor for the survival and prognosis of patients with gastric cancer, which is expected to be an independent marker of poor prognosis. Key words: Stomach neoplasms; Hypoxia-inducible factor 1; Pathology, clinical; Prognosis

Molecular mechanism of the role of carbamyl erythropoietin in treating diabetic retinopathy rats.

The aim of the present study was to investigate the therapeutic effects of carbamyl erythropoietin (CEPO) and safflor yellow (SY) in the treatment of rats with diabetic retinopathy (DR) as well as exploring the mechanism of action. Male SD rats were used to establish a diabetes model and streptozotocin-induced retinopathy was also performed in rats. A total of 126 rats with DR were obtained, and model rats were randomly divided into the model (n=42), experimental (n=42) and control (n=42) groups. The rats in the model group were injected with saline, the rats in the experimental group were treated with CEPO, and the rats in the control group were treated with SY. After treatment for 2 weeks, the retinas were harvested for quantitative analysis of the mRNA expression levels of angiogenesis-promoting and -inhibiting molecules, apoptosis-promoting and -inhibiting molecules, and oxidative stress pathway-related factors by Reverse transcription-quantitative PCR (RT-qPCR). No significant differences in expression levels of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), angiopoietin (Ang-1), tissue kallikrein (TKLK) and pigment epithelium-derived factor (PEDF) were observed between the experimental and model groups (P>0.05). The expression levels of apoptosis-promoting molecules Bcl-2 related X protein (Bax) and cysteine aspartate specific protease (caspase-3) mRNA in the retina of the experimental group was significantly lower than those in the control group (P<0.05). The expression levels of Bcl-2 and survivin mRNA were significantly higher in the experimental group than in the control group (P<0.05). The expression levels of the oxidative stress pathway nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and NAD(P)H quinone dehydrogenase 1 (NQO1) mRNA were significantly higher in the experimental group than in the control group. Therefore, the therapeutic effects of CEPO in treating DR are better than those of SY. As a result, CEPO may inhibit apoptosis and oxidative stress damage of retinal tissue cells in DR rats without affecting angiogenesis.