Hypoxia-inducible Factor-1α Levels Research Articles

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.

Association of Circulating Levels of Hypoxia-Inducible Factor-1α and miR-210 with Photosensitivity in Systemic Lupus Erythematosus Patients.

miR-210, a key hypoxamiR, regulates hypoxia and inflammation-linked hypoxia. Systemic lupus erythematosus (SLE), a chronic autoimmune disease, is responsible for many pathological disorders, including photosensitivity. This study aimed to find the correlation between circulating miR-210/HIF-1α levels and photosensitivity in SLE patients and other SLE-associated pathological complications in a single-center case-control study. The study population comprised 104 SLE Egyptian patients with photosensitivity, 32 SLE patients without photosensitivity, and 32 healthy subjects. SLE activity was assessed for all patients using the SLE Disease Activity Index (SLEDAI). Clinical complications/manifestations and hematological/serological analyses were recorded. HIF-α concentration was investigated by ELISA, and miR-210 expression was analyzed by qRT-PCR. The results revealed that circulating miR-210 was significantly increased in the SLE/photosensitivity group versus the SLE and control groups. The additional occurrence of malar rash, oral ulcers, renal disorders, or hypertension resulted in a higher expression of miR-210. SLEDAI activity status showed no effect on miR-210. Erythrocyte sedimentation rate, white blood cells, hemoglobin, platelets, patient age, and disease duration were positively correlated with circulatory miR-210. HIF-α concentration was significantly induced in the SLE/photosensitivity group versus the SLE and control groups. In SLE/photosensitivity, the presence of renal disorders and hypertension resulted in the highest HIF-α concentrations. A strong positive correlation was recorded between HIF-α concentration and circulatory miR-210 in SLE/photosensitivity patients (r = 0.886). The dysregulation of circulating miR-210/HIF-1α levels in SLE/ photosensitivity patients is controlled by the presence of additional pathological complications, and results suggest that the hypoxia pathway might interact positively with the pathogenesis and disease progression of SLE.

Anti-Arthritic Effect of Edaravone Against Complete Freund Adjuvant Induced Arthritis via Osteoclast Differentiation and HIF-1α-VEGF-ANG-1 Axis.

Bone dysfunction is a crucial problem that occurs during rheumatoid arthritis (RA) disease. Osteoclast plays a significant role in bone resorption and osteoclast differentiation and its enhancement of bone destruction. Edaravone remarkably exhibited free radical scavenging and anti-inflammatory effects. The objective of the current investigation is to comfort the inhibitory effect of Edaravone (ED) against complete Freund adjuvant (CFA) rat model via inhibition of angiogenesis and inflammation. Subcutaneous injection of CFA (1%) was used to induce arthritis; the rats were divided into different groups and received the oral administration of ED. Paw edema, body weight, and arthritis score were regularly estimated. Biochemical parameters were estimated, respectively. We also estimate the level of hypoxia-inducible factor-1α (HIF-1α), angiopoietin 1 (ANG-1), and vascular endothelial growth factor (VEGF). We also checked into how ED affected the differentiation of osteoclasts utilising a co-culture system with monocytes and synovial fibroblasts in arthritis rats. ED treatment significantly (P<0.001) suppressed the arthritis score and paw edema and improved the body weight. ED treatment significantly (P<0.001) altered the antioxidant parameters and pro-inflammatory cytokines: inflammatory mediator nuclear kappa B factor (NF-κB), cyclooxygenase-2 (COX-2), and prostaglandin E2 (PGE2), respectively. Furthermore, ED treatment significantly (P<0.001) suppressed the level of ANG-1, HIF-1α, and VEGF, respectively. The results suggest that ED suppressed osteoclast differentiation and also decreased the level of cytokines and osteopontin (OPN), receptor activator for nuclear factor-κ B Ligand (RANKL) and macrophage colony stimulating factor (M-CSF) in the co-culture supernatant of monocytes and synovial fibroblasts. Edaravone could mitigate CFA via inhibiting angiogenesis and inflammatory reactions, which may be linked with the HIF-1α-VEGF-ANG-1 axis and also enhance the bone destruction of murine arthritis via suppression of osteoclast differentiation and inflammatory reaction.

Tricaprin can prevent the development of AAA by attenuating aortic degeneration

Medical therapeutic options to prevent rupture of abdominal aortic aneurysm (AAA), a critical event, must be developed. Moreover, further understanding of the process of AAA development and rupture is crucial. Previous studies have revealed that aortic hypoperfusion can induce the development of AAA, and we successfully developed a hypoperfusion-induced AAA animal model. In this study, we examined the effects of medium-chain triglycerides (MCTs), tricaprylin (C8-TG) and tricaprin (C10-TG), on hypoperfusion-induced AAA rat model. We estimated the effects of MCTs on aortic pathologies, mechanical properties of the aorta, and development of AAA. C10-TG, but not C8-TG, significantly suppressed AAA development and completely prevented the rupture. We observed that C10-TG prevented the development and rupture of AAA, but not C8-TG. Additionally, regression of AAA diameter was observed in the C10-TG group. Pathological analysis revealed C10-TG improved the hypoperfusion-induced increase in hypoxia-inducible factor-1α levels, medial smooth muscle cells (SMCs) loss, degeneration of aortic elastin and collagen fibers, and loss of aortic wall elasticity. In addition, regression of the formed AAA was observed by administration of C10-TG after AAA formation. C10-TG administration after AAA formation improved degeneration of AAA wall including degradation of aortic elastin and collagen fibers, stenosis of vasa vasorum, and loss of medial SMCs. These data suggest C10-TG can prevent AAA by attenuating aortic hypoperfusion and degeneration. Considering the clinical safety of C10-TG, C10-TG can be a promising AAA drug candidate.

Oxygen-generating polymer vesicles for enhanced sonodynamic tumor therapy.

The efficacy of sonodynamic therapy (SDT) is often limited by the insolubility of sonosensitizers and unfavorable hypoxia tumor microenvironment. To meet this challenge, an oxygen-generating polymer vesicle is developed to achieve enhanced SDT. The hydrophilic coronas and the hydrophobic membrane of polymer vesicles can function as different modules for the simultaneous delivery of manganese dioxide and chlorine e6 (designated as Ce6-MnO2-PVs). These Ce6-MnO2-PVs exhibited high catalase mimetic activity and could efficiently generate reactive oxygen species upon ultrasound activation. In vivo results showed that Ce6-MnO2-PVs almost completely eradicated the subcutaneous tumors (94% volume reduction) without any obvious systemic toxicity. Moreover, these Ce6-MnO2-PVs showed effective behavior for the attenuation of crucial tumor progression-releated factors. Specially, the expression levels of both hypoxia-inducible factor-1α and vascular endothelial growth factor at 4 h post-injection detected by immunofluorescence were reduced by 66% and 52%, respectively. These findings suggest that Ce6-MnO2-PVs may serve as an effective and safe platform for enahnced SDT in hypoxic tumors.

Effect of hypoxia on HIF-1α/MDR1/VEGF expression in gastric cancer cells treated with 5-fluorouracil.

Fluorouracil chemotherapeutic drugs are the classic treatment drugs of gastric cancer. But the problem of drug resistance severely limits their clinical application. This study aims to investigate whether hypoxia microenvironment affects gastric cancer resistance to 5-fluorouracil (5-FU) and discuss the changes of gene and proteins directly related to drug resistance under hypoxia condition. Gastric cancer cells were treated with 5-FU in hypoxia/normoxic environment, and were divided into a Normoxic+5-FU group and a Hypoxia+5-FU group. The apoptosis assay was conducted by flow cytometry Annexin V/PI double staining. The real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were used to detect the expression level of hypoxia inducible factor-1α (HIF-1α), multidrug resistance (MDR1) gene, P-glycoprotein (P-gp), and vascular endothelial growth factor (VEGF) which were related to 5-FU drug-resistance. We analyzed the effect of hypoxia on the treatment of gastric cancer with 5-FU. Compared with the Normoxic+5-FU group, the apoptosis of gastric cancer cells treated with 5-FU in the Hypoxia+5-FU group was significantly reduced (P<0.05), and the expression of apoptosis promoter protein caspase 8 was also decreased. Compared with the the Normoxic+5-FU group, HIF-1α mRNA expression in the Hypoxia+5-FU group was significantly increased (P<0.05), and the mRNA and protein expression levels of MDR1, P-gp and VEGF were also significantly increased (all P<0.05). The increased expression of MDR1, P-gp and VEGF had the same trend with the expression of HIF-1α. Hypoxia is a direct influencing factor in gastric cancer resistance to 5-FU chemotherapy. Improvement of the local hypoxia microenvironment of gastric cancer may be a new idea for overcoming the resistance to 5-FU in gastric cancer.

Elevation of Anticancer Drug Toxicity by Caffeine in Spheroid Model of Human Lung Adenocarcinoma A549 Cells Mediated by Reduction in Claudin-2 and Nrf2 Expression

Claudin-2 (CLDN2), a component of tight junctions, is abnormally expressed in human lung adenocarcinoma tissue. CLDN2 contributes to chemoresistance in human lung adenocarcinoma-derived A549 cells, and it may be a target for cancer therapy. Here, we found that coffee ingredients, namely caffeine and theobromine, decreased the protein level of CLDN2 in human lung adenocarcinoma-derived A549 cells. In contrast, other components, such as theophylline and chlorogenic acid, had no effect. These results indicate that the 7-methyl group in methylxanthines may play a key role in the reduction in CLDN2 expression. The caffeine-induced reduction in the CLDN2 protein was inhibited by chloroquine, a lysosome inhibitor. In a protein-stability assay using cycloheximide, CLDN2 protein levels decreased faster in caffeine-treated cells than in vehicle-treated cells. These results suggest that caffeine accelerates the lysosomal degradation of CLDN2. The accumulation and cytotoxicity of doxorubicin were dose-dependently increased, which was exaggerated by caffeine but not by theophylline in spheroids. Caffeine decreased nuclear factor-erythroid 2-related factor 2 (Nrf2) levels without affecting hypoxia-inducible factor-1α levels. Furthermore, caffeine decreased the expression of Nrf2-targeted genes. The effects of caffeine on CLDN2 expression and anticancer-drug-induced toxicity were also observed in lung adenocarcinoma RERF-LC-MS cells. We suggest that caffeine enhances doxorubicin-induced toxicity in A549 spheroids mediated by the reduction in CLDN2 and Nrf2 expression.

Overexpression of hypoxia-inducible factor 1α and excessive vascularization in the peri-implantation endometrium of infertile women with chronic endometritis.

Chronic endometritis (CE) contributes to impaired endometrial receptivity and is closely associated with poor in vitro fertilization (IVF) outcomes. However, the mechanisms underlying CE are unclear. Here, we investigated the role of the hypoxic microenvironment and endometrial vascularization in the peri-implantation endometrium of infertile women with CE. This retrospective study involved 15 fertile women and 77 infertile patients diagnosed with CE based on CD138+ ≥1/10 high-power fields (HPFs). The CE patients were divided into Group 1 (CD138+ 1-4/10 HPFs, 53 cases) and Group 2 (CD138+ ≥5/10 HPFs, 24 cases). The expression levels of hypoxia-inducible factor 1α (HIF1α), vascular endothelial growth factor A (VEGFA), and vascular endothelial growth factor receptor 2 (VEGFR2) in peri-implantation endometrium were assessed by qRT-PCR and western blot analyses. Spatial levels of HIF1α, VEGFA, and VEGFR2 in various endometrial compartments was determined using immunohistochemistry and H-score analysis. Microvascular density (MVD) was determined using CD34 staining and scored using Image J. Finally, we used qRT-PCR to assess changes in the expression of HIF1α, VEGFA, and VEGFR2 in CE patients after treatment with first-line antibiotics. Relative to Group 1 and control group, during the implantation window, protein and mRNA levels of HIF1α, VEGFA, and VEGFR2 were markedly high in Group 2 (P<0.05). H-score analysis showed that HIF1α, VEGFA, and VEGFR2 in the luminal, glandular epithelium, and stromal compartments were markedly elevated in Group 2, comparing to control group and Group 1 (P<0.05). Moreover, markedly elevated MVD levels were observed in Group 2. Notably, the above indexes did not differ significantly in the control group versus Group 1. Treatment with antibiotics significantly suppressed the endometrial HIF1α and VEGFA levels in CE-cured patients. Here, we for the first time report the upregulation of HIF1α, VEGFA, and VEGFR2, as well as excessive endometrial vascularization in the peri-implantation endometrium of CE patients. Our findings offer new insights into reduced endometrial receptivity in CE-associated infertility.

Indole-3-carbinol ameliorated the neurodevelopmental deficits in neonatal anoxic injury in rats.

Neonatal anoxia is linked to long-lasting neurodevelopmental deficits. Due to the lack of pharmacological intervention to treat neonatal anoxia, there is interest in finding new molecules for its treatment. Indole-3-carbinol (I3C) has shown neuroprotective effects in some disease conditions. However, the neuroprotective role of I3C in neonatal anoxia has not been explored. Consequently, we have investigated the effect of I3C on neonatal anoxia-induced brain injury and neurodevelopmental deficits. Rat pups after 30 h of birth were subjected to two episodes of anoxia (10min in each) at a time interval of 24 h by flowing 100% nitrogen. I3C was administered within 30 min of the second episode of anoxia on a postnatal day (PND) 3 and continued for PND 9. Neurodevelopmental deficits, cortical mitochondrial membrane potential (MMP), opening of mitochondrial permeability transition pore (MPTP), electron transport chain (ETC) enzyme activities, oxidative stress, hypoxia-inducible factor-1α (HIF-1α) levels, histopathological changes, and apoptosis were measured. I3C treatment dose-dependently ameliorated the neurodevelopmental deficits and somatic growth in anoxic pups. I3C improved mitochondrial function by enhancing the MMP, mitochondrial ETC enzymes, and antioxidants. It blocked the MPTP opening and release of cytochrome C in anoxic pups. Further, I3C reduced the elevated cortical HIF-1α in neonatal anoxic pups. Furthermore, I3C ameliorated histopathological abnormalities and mitochondrial-mediated apoptotic indicators Cyt C, caspase-9, and caspase-3. Our study concludes that I3C improved neuronal development in anoxic pups by enhancing mitochondrial function, reducing HIF-1α, and mitigating apoptosis.

Novel Oxygen-Dependent Degradable Immunotoxin Regulated by the Ubiquitin-Proteasome System Reduces Nonspecific Cytotoxicity.

The use of bacterial toxins as antitumor agents has received considerable attention. Immunotoxins based on antigen recognition of single-chain antibodies have been widely explored for cancer therapy. Despite their impressive killing effect on tumor cells, immunotoxins still display unspecific toxicity with undesired side effects. High levels of hypoxia-inducible factor 1α (HIF-1α) are well-known indicators of hypoxia in cancer cells. In this study, different linkers were employed to fuse the immunotoxin DAB389-4D5 scFv (DS) with the oxygen-dependent degradation domain (ODDD) of HIF-1α, a domain selectively facilitating the accumulation of HIF-1α under hypoxia, to construct the oxygen-dependent degradable immunotoxin DS-ODDD (DSO). The engineered fusion protein DSO-2 containing a linker (G4S)3 possesses the best killing effect on cancer cells under hypoxia and displayed considerably reduced nonspecific toxicity to normal cells under normoxic conditions. Flow cytometry, immunofluorescence, and immunoblot analyses demonstrated that DSO-2 was degraded via the ubiquitin-proteasome pathway regulated by the oxygen-sensitive mechanism. Western blot analysis indicated that the degradation of DSO-2 significantly decreased the activation of apoptosis-related molecules in normal cells. The engineered immunotoxin with oxygen-sensing properties developed herein is a potential therapeutic agent for cancer treatment.

Pentoxifylline inhibits phosgene-induced lung injury via improving hypoxia

Inhalation of high concentrations of phosgene often causes pulmonary edema, which obstructs the airway and causes tissue hypoxia. There is currently no specific antidote. This study was performed to investigate the effect behind pentoxifylline (PTX) treatment for phosgene-induced lung injury in rat models. Rats were exposed to phosgene. The protein levels of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), and occludin proteins in lung tissue were determined. The effect of both prophylactic and therapeutic administration of PTX (50 mg/kg and 100 mg/kg) was evaluated. The lung permeability index and HIF-1α protein level increased, the arterial blood oxygenation index (PaO2/FIO2 ratio) and occludin protein level decreased significantly 6 h after phosgene exposure (P < 0.05). PTX exerted protective effects by HIF-1α-VEGF-occludin signaling pathway to some extent. Moreover, prophylactic, but not therapeutic administration of PTX (100 mg/kg), exhibited a significant protective effect. Pretreatment with PTX protected against phosgene-induced lung injury, possibly by inhibiting differential expression of HIF-1α, VEGF, and occludin.

Caveolin-1 suppresses hippocampal neuron apoptosis via the regulation of HIF1α in hypoxia in naked mole-rats.

Naked mole-rats (NMRs) (Heterocephalus glaber) are highly social and subterranean rodents with large communal colonies in burrows containing low oxygen levels. The inhibition of severe hypoxic conditions is of particular interest to this study. To understand the mechanisms that facilitate neuronal preservation during hypoxia, we investigated the proteins regulating hypoxia tolerance in NMR hippocampal neurons. Caveolin-1 (Cav-1), a transmembrane scaffolding protein, confers prosurvival signalling in the central nervous system. The present study aimed to investigate the role of Cav-1 in hypoxia-induced neuronal injury. Western blotting analysis and immunocytochemistry showed that Cav-1 expression was significantly upregulated in NMR hippocampal neurons under 8% O2 conditions for 8 h. Cav-1 alleviates apoptotic neuronal death from hypoxia. Downregulation of Cav-1 by lentiviral vectors suggested damage to NMR hippocampal neurons under hypoxic conditions in vitro and in vivo. Overexpression of Cav-1 by LV-Cav-1 enhanced hypoxic tolerance of NMR hippocampal neurons in vitro and in vivo. Mechanistically, the levels of hypoxia inducible factor-1α (HIF-1α) are also increased under hypoxic conditions. After inhibiting the binding of HIF-1α to hypoxia response elements in the DNA by echinomycin, Cav-1 levels were downregulated significantly. Furthermore, chromatin immunoprecipitation assays showed the direct role of HIF1α in regulating the expression levels of Cav-1 in NMR hippocampal neurons under hypoxic conditions. These findings suggest that Cav-1 plays a critical role in modulating the apoptosis of NMR hippocampal neurons and warrant further studies targeting Cav-1 to treat hypoxia-associated brain diseases.

Hypoxia and low temperature upregulate transferrin to induce hypercoagulability at high altitude

AbstractStudies have shown significantly increased thromboembolic events at high altitude. We recently reported that transferrin could potentiate blood coagulation, but the underlying mechanism for high altitude–related thromboembolism is still poorly understood. Here, we examined the activity and concentration of plasma coagulation factors and transferrin in plasma collected from long-term human residents and short-stay mice exposed to varying altitudes. We found that the activities of thrombin and factor XIIa (FXIIa) along with the concentrations of transferrin were significantly increased in the plasma of humans and mice at high altitudes. Furthermore, both hypoxia (6% O2) and low temperature (0°C), 2 critical high-altitude factors, enhanced hypoxia-inducible factor 1α (HIF-1α) levels to promote the expression of the transferrin gene, whose enhancer region contains HIF-1α binding site, and consequently, to induce hypercoagulability by potentiating thrombin and FXIIa. Importantly, thromboembolic disorders and pathological insults in mouse models induced by both hypoxia and low temperature were ameliorated by transferrin interferences, including transferrin antibody treatment, transferrin downregulation, and the administration of our designed peptides that inhibit the potentiation of transferrin on thrombin and FXIIa. Thus, low temperature and hypoxia upregulated transferrin expression–promoted hypercoagulability. Our data suggest that targeting the transferrin-coagulation pathway is a novel and potentially powerful strategy against thromboembolic events caused by harmful environmental factors under high-altitude conditions.

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-inducible factor-1α and ischemia-modified albumin levels in intensive care COVID-19 Patients.

In this study, it was aimed to evaluate the hypoxia-inducible factor-1α (HIF-1α) and ischemia-modified albumin (IMA) levels of patients diagnosed with COVID-19 in the intensive care unit (ICU) and healthy controls. To our knowledge, this is the first study investigate HIF-1α and IMA levels in COVID-19 patients in ICUs and comparing them with a healthy control group. For this reason, our study is original and will contribute to the literature. A total of 70 intensive care patients diagnosed with COVID-19, and 72 healthy controls were included in the study. When we compared the patient and healthy control group; there were no statistically significant differences between the groups in terms of age and gender (p>0.05). No exitus was observed in the patient group. We found weak correlation between HIF-1α and IMA (r: 0.320). However, there were statistically significant differences in HIF-1α and IMA levels in the patient group. The receiver operating characteristic (ROC) curve demonstrated an area under curve (AUC) value of 0.651 for HIF-1α and 0.937 for IMA. The HIF-1α and IMA levels were significantly higher among COVID-19 patients in ICU compared with healthy controls. HIF-1α and IMA levels can be used as reliable markers for the prognosis of COVID-19.

Gamma-aminobutyric acid enhances hypoxia tolerance of juvenile Chinese mitten crab (Eriocheir sinensis) by regulating respiratory metabolism and alleviating neural excitotoxicity

With climate change and intensive aquaculture development, environmental hypoxia in aquaculture water has become a common challenge for many aquatic species. Therefore, it is crucial to improve the hypoxic tolerance of animals through nutritional strategies. This study explored the positive role of dietary gamma-aminobutyric acid (GABA) supplementation in enhancing hypoxia tolerance of juvenile Eriocheir sinensis through respiratory regulation and alleviation of hypoxia-induced neural excitotoxicity. Acute hypoxia stress significantly up-regulated the mRNA expression level of hypoxia-inducible factor 1α, oxygen consumption rate and anaerobic respiratory metabolism-related enzyme activities. On the other hand, aerobic respiratory metabolism-related enzyme activities were significantly decreased. However, dietary GABA supplementation remodeled the respiratory metabolism pattern of juvenile crabs exposed to hypoxia stress. In addition, acute hypoxic stress significantly increased the contents of free glutamate and GABA in the nervous tissue. The expression levels of N-Methyl-d-aspartate-related receptor genes and calcium-dependent degradation enzyme-related genes were significantly up-regulated. Similarly, neuronal apoptosis rates, expression levels of apoptosis-related genes, and vesicular glutamate transporter genes were also significantly increased. The high-affinity neuronal glutamate transporter decreased significantly in the crabs exposed to hypoxia stress. However, dietary GABA supplementation could effectively prevent acute hypoxia stress-induced neural excitotoxicity. Furthermore, dietary GABA could significantly improve the redox status in vivo exposed to hypoxia stress. In conclusion, acute hypoxia stress can affect respiratory metabolism and redox state and induce neural excitotoxicity in juvenile E. sinensis. GABA supplementation could improve hypoxia tolerance through multiple physiological regulation pathways.

Increase in Anticancer Drug-Induced Toxicity by Fisetin in Lung Adenocarcinoma A549 Spheroid Cells Mediated by the Reduction of Claudin-2 Expression.

Claudin-2 (CLDN2), a component of tight junction, is involved in the reduction of anticancer drug-induced toxicity in spheroids of A549 cells derived from human lung adenocarcinoma. Fisetin, a dietary flavonoid, inhibits cancer cell growth, but its effect on chemosensitivity in spheroids is unknown. Here, we found that fisetin (20 μM) decreases the protein level of CLDN2 to 22.3%. Therefore, the expression mechanisms were investigated by real-time polymerase chain reaction and Western blotting. Spheroids were formed in round-bottom plates, and anticancer drug-induced toxicity was measured by ATP content. Fisetin decreased the phosphorylated-Akt level, and CLDN2 expression was decreased by a phosphatidylinositol 3-kinase (PI3K) inhibitor, suggesting the inhibition of PI3K/Akt signal is involved in the reduction of CLDN2 expression. Hypoxia level, one of the hallmarks of tumor microenvironment, was reduced by fisetin. Although fisetin did not change hypoxia inducible factor-1α level, it decreased the protein level of nuclear factor erythroid 2-related factor 2, a stress response factor, by 25.4% in the spheroids. The toxicity of doxorubicin (20 μM) was enhanced by fisetin from 62.8% to 40.9%, which was rescued by CLDN2 overexpression (51.7%). These results suggest that fisetin can enhance anticancer drug toxicity in A549 spheroids mediated by the reduction of CLDN2 expression.

Berberis dictyophylla F. inhibits angiogenesis and apoptosis of diabetic retinopathy via suppressing HIF-1α/VEGF/DLL-4/Notch-1 pathway

Ethnopharmacological relevanceXiao Bopi (XBP, སྐྱེར་བའི་བར་ཤུན།), as a classical Tibetan medicinal plant in China, which derived from the stem bark of Berberis dictyophylla F., has the function of “clearing heat and decreasing mKhris-pa”. And it traditionally is utilized to treat the diabetes mellitus and its complications, such as diabetic retinopathy (DR). However, its underlying mechanisms remain unclear. Aim of the studyThe purpose of this study aimed to explore the microvascular protection of water extract of XBP against the spontaneous retinal damage of db/db mice. Meanwhile, the underlying mechanisms of XBP on angiogenesis and apoptosis were further interpreted. Materials and methodsWe firstly used high-performance liquid chromatography to detected the representative chemical ingredients in the water extract of XBP. The DR model of db/db mice was then randomly divided into five groups: model group, calcium dobesilate (0.23 g/kg) group, and the water extract of XBP (0.375, 0.75 and 1.5 g/kg, respectively) groups. After 8 weeks of continuous administration, the parameters including body weight, fasting blood glucose, oral glucose tolerance test and insulin tolerance test were measured. The pathological changes and abnormal angiogenesis of the retina were detected by optical coherence tomography, HE, periodic acid–Schiff staining and transmission electron microscopy. Simultaneously, molecular docking was used to predict the potential connections between representative ingredients in XBP and angiogenesis/apoptosis-related proteins. The level of angiogenesis-related proteins and gene hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth (VEGF), delta-like ligand 4 (DLL-4) and Notch-1 were estimated by immunofluorescence analyses and real time-PCR. Further, TUNEL staining and immunofluorescence analyses were performed to investigate the apoptotic phenomenon and the expression of Bax, Bcl-2, Apaf-1, Cyto-c and cleaved caspase-3 and cleaved caspase-9 in the retina. ResultsPhytochemical analysis revealed that magnoflorine, jatrorrhizine, palmatine and berberine were principally representative ingredients in XBP. The results demonstrated that XBP effectively increased glucose tolerance and insulin sensitivity, whereas no effect on body weight of DR mice. Moreover, retinal thickening, pathological and retinal ultrastructure changes in DR mice were evidently ameliorated by XBP. The molecular docking results demonstrated that the main components of XBP and the protein of angiogenesis and apoptosis had a potential bind. XBP restrained the gene and protein levels of HIF-1α, VEGF, DLL-4 and Notch-1 in retina. Additionally, the TUNEL-positive cell rate and the down-regulated proteins of Bax, Apaf-1, Cyto-c, cleaved Caspase-3 and cleaved Caspase 9 and increased Bcl-2 level were revised by XBP. ConclusionsTo sum up, the results suggested that XBP against DR could attribute to alleviating angiogenesis and apoptosis by suppressing the HIF-1α/VEGF/DLL-4/Notch-1 pathway. This evidence sheds a new light on the potential mechanisms of XBP in the treatment of DR.

Metformin alleviates the cognitive impairment caused by aluminum by improving energy metabolism disorders in mice

Long-term exposure to environmental aluminum was found to be related to the occurrence and development of neurodegenerative diseases. Energy metabolism disorders, one of the pathological features of neurodegenerative diseases, may occur in the early stage of the disease and are of potential intervention significance. Here, sub-chronic aluminum exposure mouse model was established, and metformin was used to intervene. We found that sub-chronic aluminum exposure decreased the protein levels of phosphorylation AMPK (p-AMPK), glucose transporter 1 (GLUT1) and GLUT3, taking charge of glucose uptake in the brain, reduced the levels of lactate shuttle-related proteins monocarboxylate transporter 4 (MCT4) and MCT2, as well as lactate content in the cerebral cortex, while increased hypoxia-inducible factor-1α (HIF-1α) level to drive downstream pyruvate dehydrogenase kinase 1 (PDK1) expression, thereby inhibiting pyruvate dehydrogenase (PDH) activity, and ultimately led to ATP depletion, neuronal death, and cognitive dysfunction. However, metformin could rescue these injuries. Thus, it came to a conclusion that aluminum could damage glucose uptake, interfere with astrocyte-neuron lactate shuttle (ANLS), interrupt the balance in energy metabolism, and resulting in cognitive function, while metformin has a neuroprotective effect against the disorder of energy metabolism caused by aluminum in mice.