Hypoxia-inducible Factor-1α Levels Research Articles

Sevoflurane alleviates intestinal ischemia-reperfusion injury in aged mice.

Sevoflurane is a widely used inhalation anesthetic during the perioperative period. Recent studies have suggested that sevoflurane has an enteroprotective effect, but its mechanism is unclear. To explore the mechanism of sevoflurane in intestinal ischemia-reperfusion injury, an intestinal ischemia-reperfusion injury mouse model was established. First, intestinal ischemia-reperfusion injury was compared between aged and young mice. The results showed that intestinal ischemia-reperfusion injury caused pathological intestinal injury and disrupted the intestinal mucosal barrier. The aged mice had more severe intestinal ischemia-reperfusion injury than the young mice and therefore had a lower survival rate. The aged mice subsequently received sevoflurane via inhalation. Sevoflurane alleviated the pathological injury to the intestinal mucosa and repaired the function of the intestinal mucosal barrier in aged mice, thus increasing the level of intestinal mucosal hypoxia-inducible factor-1α and improving the survival rate of aged mice. However, preoperative administration of the hypoxia-inducible factor-1α inhibitor BAY87-2243 could counteract the enteroprotective effect of sevoflurane and lower the expression level of heme oxygenase-1, a downstream antioxidant enzyme of hypoxia-inducible factor-1α. Our findings suggest that sevoflurane alleviates intestinal ischemia-reperfusion injury in aged mice by repairing the intestinal mucosal barrier through the activation of hypoxia-inducible factor-1α/heme oxygenase-1, providing a new target for the treatment of intestinal ischemia-reperfusion injury in aged mice.

Quinoa Ethanol Extract Ameliorates Cognitive Impairments Induced by Hypoxia in Mice: Insights into Antioxidant Defense and Gut Microbiome Modulation.

Quinoa, rich in pharmacologically active ingredients, possesses the potential benefit in preventing cognitive impairments induced by hypoxia. In this study, the efficacy of quinoa ethanol extracts (QEE) consumption (200 and 500 mg/kg/d, respectively) against hypobaric hypoxia (HH)-induced cognitive deficits in mice was investigated. QEE significantly ameliorated hypoxic stress induced by HH, as evidenced by improvements in baseline indices and reductions in hypoxia-inducible factor 1α levels. Furthermore, QEE enhanced antioxidant defense mechanisms, alleviated neuroinflammation in brain regions associated with memory, and improved HH-induced cognitive impairments by modulating the cyclic adenosine monophosphate response element-binding protein/brain-derived neurotrophic factor signaling pathway. Higher doses generally yielded more effective outcomes than lower doses. QEE also significantly reshaped the gut microbiome structure of HH mice, inhibited gut barrier damage, and reduced lipopolysaccharide migration, thereby increasing short-chain fatty acids (SCFAs) levels. Our findings suggest that QEE may be a promising strategy for preventing hypoxia-induced cognitive impairments by maintaining gut microbiome stability and increasing SCFAs levels.

UBE2Q2 promotes tumor progression and glycolysis of hepatocellular carcinoma through NF-κB/HIF1α signal pathway.

Metabolic reprogramming, particularly the Warburg effect, plays a crucial role in the onset and progression of tumors. The ubiquitin-conjugating enzyme E2 Q2 (UBE2Q2) has been identified overexpressed in hepatocellular carcinoma (HCC). Our aim was to determine if UBE2Q2 plays a role in regulating glycolysis, contributing to the carcinogenesis of HCC. Bioinformatics analysis, western blot and qPCR were used to detect the expression of UBE2Q2. Functional experiments, proteomics analysis and subcutaneous tumors were constructed to find the biological function of UBE2Q2 in HCC. Co-immunoprecipitation, western blot and ubiquitination assays were used to identify the mechanisms involved. We found a significant association between high UBE2Q2 expression and poor prognosis in HCC patients. Functionally, UBE2Q2 was shown to advance tumor progression in HCC through both in vitro assays and in vivo assessments. Proteomics analysis and glycolysis stress tests corroborated an increase in glycolytic activity due to UBE2Q2. Our findings reveal that UBE2Q2 augments glycolysis by boosting the transcription levels of hypoxia-inducible factor 1α (HIF1α), primarily through the activation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. At the molecular level, UBE2Q2 interaction with baculoviral IAP repeat-containing 2 (cIAP1) orchestrates the K63-linked ubiquitination of receptor-interacting serine/threonine-protein kinase 1 (RIP1), which in turn, activates the NF-κB signaling pathway. Our investigation reveals that UBE2Q2 regulates the glycolysis in HCC through modulation of the NF-κB/HIF1α signaling pathway, pinpointing UBE2Q2 as a promising therapeutic target for the disease.

Hypoxia Combined With Interleukin-17 Regulates Hypoxia-Inducible Factor-1α/Endothelial Nitric Oxide Synthase Expression in Pulmonary Artery Endothelial Cells.

The pathogenesis of chronic thromboembolic pulmonary hypertension may be multifactorial and requires further studies. We explored alterations in pulmonary artery endothelial cells under the hypoxic and elevated interleukin-17 conditions that are commonly present in patients with chronic thromboembolic pulmonary hypertension. We measured the serum interleukin-17 levels in 10 chronic thromboembolic pulmonary hypertension patients and 10 healthy control persons. The expressions and localisations of hypoxia-inducible factor-1α and endothelial nitric oxide synthase were detected in tissues. The levels of hypoxia-inducible factor-1α, endothelial nitric oxide synthase, nitric oxide, and reactive oxygen species in cultured pulmonary artery endothelial cells were examined under hypoxia and/or interleukin-17 treatment. The serum interleukin-17 level was increased in chronic thromboembolic pulmonary hypertension patients. Hypoxia-inducible factor-1α was increased, and endothelial nitric oxide synthase was decreased in chronic thromboembolic pulmonary hypertension pulmonary vascular tissue. After receiving the hypoxia combined with interleukin-17 treatment, pulmonary artery endothelial cells showed increased levels of hypoxia-inducible factor-1α and phospho-endothelial nitric oxide synthase (Thr495) (p = 0.001 and 0.063, respectively) and a decreased level of endothelial nitric oxide synthase (p < 0.001). In addition, the nitric oxide level was significantly decreased (p = 0.001), whereas the reactive oxygen species level was insignificantly increased in pulmonary artery endothelial cells. Chronic thromboembolic pulmonary hypertension patients might experience increased inflammation and hypoxia due to dysregulation of the hypoxia-inducible factor-1α/endothelial nitric synthase pathway in pulmonary artery endothelial cells under inflammation and hypoxia, contributing to the pathogenesis of chronic thromboembolic pulmonary hypertension.

Sulfur dioxide controls M1 macrophage polarization by sulphenylation of prolyl hydroxylase 2 at cysteine 260.

M1 macrophage polarization plays a pivotal role in inflammation-related diseases. However, the endogenous regulatory factors and mechanisms underlying M1 macrophage polarization have not been entirely clarified. This study aimed to explore whether endogenous sulfur dioxide (SO2) is involved in M1 macrophage polarization and its mechanism. In the study, we found that the endogenous SO2/aspartate aminotransferase1 (AAT1) pathway was downregulated during M1 polarization of macrophages induced by lipopolysaccharide (LPS) stimulation, and supplementation with SO2 donors or AAT1 overexpression restored SO2 content, suppressed protein expression of inducible nitric oxide synthase, restrained mRNA level of M1 phenotype-related genes tumor necrosis factor α, interleukin-1β and interleukin-12β and decreased the CD86 expression. In addition, AAT1-knockdowned macrophages exhibited reduced level of hypoxia-inducible factor-1α (HIF-1α) hydroxylation, elevated HIF-1α protein level, and polarization into M1-type, while supplementation with SO2 reversed the above effects. Mechanistically, SO2 maintained prolyl hydroxylase (PHD) activity in a thiol-dependent manner. SO2 maintained PHD2 activity by sulphenylating PHD2 at Cys260, thereby reducing HIF-1α protein levels and subsequently inhibiting M1 macrophage polarization. Besides, SO2 enhanced PHD2 sulphenylation, inhibited M1 macrophage polarization, and alleviated lung damage in a mouse model of LPS-induced acute lung injury. These results suggested that downregulation of the endogenous SO2/AAT1 pathway was a pivotal mechanism for M1 macrophage polarization. SO2 maintained PHD2 activity via sulphenylation of Cys260, and promoted HIF-1α hydroxylation and degradation, thereby impeding M1 macrophage polarization.

Apocynin and Hyperbaric Oxygen Therapy Improve Renal Function and Structure in an Animal Model of CKD.

Chronic kidney disease (CKD) is a progressive pathological condition which results in the severe fibrosis of the kidneys. However, the mechanisms of CKD progression and fibrogenesis remain unclear. We wanted to examine the effects that apocynin and hyperbaric oxygen therapy (HBOT) have on renal function and structure in animals with CKD induced through 5/6 nephrectomy (5/6 Nx-L). Male Wistar rats were divided in 5 groups (n = 8/group) as follows: control-sham-operated rats; Nx-L-rats with 5/6 Nx-L; APO-5/6 Nx-L + apocynin treatment; HBOT-5/6 Nx-L + hyperbaric oxygen treatment, and APO+HBOT-5/6 Nx-L, treated with both treatments. All treatments started 4 weeks after the final step of CKD induction and lasted for 4 weeks. At the end of the experiment, urine samples were collected for the proteinuria assessment and the mean arterial pressure (MAP) was measured. Kidneys were collected for histopathological, Western blot, and immunohistochemical analyses. All treatments significantly decreased MAP compared to the Nx-L group (p < 0.001). In the APO and APO+HBOT groups, the level of proteinuria was decreased compared to the Nx-L group (p < 0.05 and p < 0.01, respectively). All examined treatments significantly decreased the intensity of lesions in the kidney compared to those observed in the Nx-L group (p < 0.001). Isolated treatments with apocynin and HBOT induced a significant decrease in desmin expression compared to the Nx-L group (p < 0.05); meanwhile, they did not affect the levels of fibronectin (FN) and hypoxia-inducible factor-1α (HIF-1α). Combined treatment did not affect desmin expression levels; however, it induced a significant increase in fibronectin expression compared to Nx-L (p < 0.001). Apocynin treatment decreased BP and protein loss, and it improved renal morphology at least partly through the downregulation of desmin expression without changing FN and HIF-1α. Hyperbaric oxygen therapy improved hypertension but failed to significantly affect the level of proteinuria. Combined treatment (apocynin and HBOT) normalized blood pressure (BP) values, renal function, and improved kidney structure by modulating FN and HIF-1α, without affecting desmin protein expression. Further studies are needed to elucidate the mechanisms of slowing down the progression of CKD in this experimental model.

Association of serum HIF-1α levels with coronary artery calcification in patients of non-dialysis chronic kidney disease

Vascular calcification is the main cause of death in patients with chronic kidney disease (CKD). The study aims to investigate the risk factor affecting coronary artery calcification (CAC), and the relationship between serum hypoxia-inducible factor-1α (HIF-1α) levels and CAC in non-dialysis CKD patients. One hundred and twenty-three patients were selected in the final analysis. Spearman rank correlation analysis assessed the correlation between HIF-1α levels and CAC scores. Logistic regression analysis was utilized to assess potential risk variables associated with CAC. A ROC curve was drawn to analyze the diagnostic value of HIF-1α in non-dialysis CKD patients with CAC. Compared to the non-CAC group, the CAC group was older age, with a higher proportion of males, smokers, hypertension and diabetes, lower eGFR and HDL-C, and higher SBP and HIF-1α levels. As the HIF-1α levels went up, the proportion of patients with VC increased, as well as Agatston scores. Spearman rank correlation analysis showed that HIF-1α levels were positively correlated with VC and Agatston scores. Logistic regression analysis indicated that being male (OR = 0.242, P = 0.036), older age (OR = 1.093, P < 0.001), and increased HIF-1α levels (OR = 1.002, P = 0.025) were risk factors for the occurrence of CAC. Furthermore, ROC curve analysis determined that a HIF-1α cutoff value of 451.177 pg·mL-1 provided the best diagnostic value for non-dialysis CAC, with a sensitivity of 65.8% and a specificity of 80.9%. The prevalence of CAC is high in non-dialysis CKD patients, with old age and male gender being traditional risk factors for CAC occurrence. HIF-1α positively correlate with both CAC and VC, which can provide certain diagnostic values for non-dialysis CAC.

Plasmodium infection downregulates hypoxia‑inducible factor 1α expression to suppress the vascularization and tumorigenesis of liver cancer.

Liver cancer is characterized by hypervascularization. Anti-angiogenic agents may normalize the tumor vasculature and improve the efficacy of other treatments. The present study aims to investigate the anti-angiogenic effect of Plasmodium infection in a mouse model of implanted liver cancer cells. HepG2 cells were injected into the left liver lobe of nude mice as a model of in situ hepatic tumorigenesis. Plasmodium yoelii parasitized erythrocytes were administered in the animal model of liver cancer to introduce Plasmodium infection. The tumor growth and microvascular density were determined in the presence or absence of Plasmodium infection. The expression levels of hypoxia-inducible factor 1α (HIF-1α) and angiogenesis-related factors were evaluated using western blotting and reverse transcription-quantitative PCR analysis. The results demonstrated that Plasmodium infection suppressed tumor growth and vascularization in the mouse model of implanted HepG2 cells. Plasmodium parasites reduced the expression of pro-angiogenic factors (vascular endothelial growth factor A and angiopoietin 2), matrix metalloproteinases [(MMP)2 and MMP9] and inflammatory cytokines [tumor necrosis factor α, interleukin 6 (IL)-6) and IL-1β] in both hepatic and tumor tissues. HIF-1α was downregulated in both hepatic and tumor tissues upon Plasmodium infection, and HIF-1α overexpression rescued angiogenesis and tumor growth under the condition of Plasmodium infection. In conclusion, the results of the present study demonstrated the anti-angiogenic and anti-tumorigenic effects of Plasmodium infection on liver cancer through downregulating HIF-1α expression, indicating that Plasmodium parasites could be developed as an intervention strategy to restrain neo-angiogenesis in liver cancer.

AAV-mediated combination gene therapy of inducible Caspase 9 and miR-199a-5p is therapeutic in hepatocellular carcinoma.

Advanced-stage hepatocellular carcinoma (HCC) remains an untreatable disease with an overall survival of less than one year. One of the critical molecular mediators contributing to increased resistance to therapy and relapse, is increased hypoxia-inducible factor 1α (HIF-1α) levels, leading to metastasis of tumor cells. Several microRNAs are known to be dysregulated and impact HIF-1α expression in HCC. An in silico analysis demonstrated that hsa-miR-199a-5p is downregulated at various stages of HCC and is known to repress HIF-1α expression. Based on this analysis, we developed a combinatorial suicide gene therapy by employing hepatotropic Adeno-associated virus-based vectors encoding an inducible caspase 9 (iCasp9) and miR-199a. The overexpression of miR-199a-5p alone significantly decreased ( ~ 2-fold vs. Mock treated cells, p < 0.05) HIF-1α mRNA levels, with a concomitant increase in cancer cell cytotoxicity in Huh7 cells in vitro and in xenograft models in vivo. To further enhance the efficacy of gene therapy, we evaluated the synergistic therapeutic effect of AAV8-miR-199a and AAV6-iCasp9 in a xenograft model of HCC. Our data revealed that mice receiving combination suicide gene therapy exhibited reduced expression of HIF-1α ( ~ 4-fold vs. Mock, p < 0.001), with a significant reduction in tumor growth when compared to mock-treated animals. These findings underscore the therapeutic potential of downregulating HIF-1α during suicide gene therapy for HCC.

Chronic Peroxisome Proliferator-Activated Receptor α/γ and Cannabinoid Receptor 2 Agonist Treatments Attenuated Visceral Adipose Tissue (VAT)–Derived Extracellular Vesicle–Related VAT and Intestinal Abnormalities in Nonalcoholic Steatohepatitis Mice

This study explores the mechanisms and combined effects of chronic peroxisome proliferator-activated receptor (PPAR)α/γ and cannabinoid receptor 2 (CB2R) agonists on visceral adipose tissue (VAT)-derived extracellular vesicle (EVs) release and associated systemic/VAT inflammation, decreased VAT capillary density/fibrosis, and intestinal inflammation/hyperpermeability in nonalcoholic steatohepatitis (NASH) mice. NASH mice receiving 1 month of PPARα/γ agonist aleglitazar (10 mg/kg/day), CB2R agonist JWH015 (3 mg/kg/day) alone or combined. High EV release from VAT of NASH mice was associated with severe systemic/VAT/intestinal inflammation, reduced capillary network of VAT, and intestinal hyperpermeability. Combined JWH015 with aleglitazar treatment significantly suppressed HFD-induced obesity/adiposity, inhibited VAT expansion, reduced VAT inflammation/fibrosis, normalized VAT capillary network, and attenuated intestinal mucosal injury, inflammation, and hyperpermeability in NASH+aleg+JWH015 mice. The inhibition of AT-derived EV release and hypoxia inducible factor (HIF)1α levels in AT-derived EV, normalization of CB2R, PPARα, PPARγ, PPARγ1, PPARγ2, tight junction proteins, VEGF/CD31 expression, and downregulations of HIF1α, MCP-1 and TGFβ1 were observed in the VAT and intestine of the NASH+aleg+jwh015 group. In vitro experiments revealed that PPARα/γ and CB2R activation attenuated NASH AT-derived EV (EVnash)-induced pathogenic changes in the J774/SVEC4-10/Caco2 /3T3-L1 cell system. This study suggested that VAT-derived EVs contribute to the pathogenesis of NAFLD and that combined PPARα/γ and CB2R agonist treatment reduces VAT-released EV release and HIF1/MCP-1 signals to ameliorate hepatic steatosis and VAT/intestine abnormalities of NASH mice.

Downregulation of malic enzyme 3 facilitates progression of gastric carcinoma via regulating intracellular oxidative stress and hypoxia-inducible factor-1α stabilization

BackgroundGastric cancer (GC) is one of the most malignant cancers worldwide. Metabolism disorder is a critical characteristic of malignant tumors related to tumor progression and metastasis. However, the expression and molecular mechanism of malic enzyme 3 (ME3) in GC are rarely reported. In this study, we aim to investigate the molecular mechanism of ME3 in the development of GC and to explore its potential value as a prognostic and therapeutic target in GC.MethodME3 mRNA and protein expression were evaluated in patients with GC using RT-qPCR, WB, and immunohistochemistry, as well as their correlation with clinicopathological indicators. The effect of ME3 on proliferation and metastasis was evaluated using Cell Counting Kit-8 (CCK-8), 5-ethynyl-20-deoxyuridine (EdU) assay, transwell assay, wound healing assay, and subcutaneous injection or tail vein injection of tumor cells in mice model. The effects of ME3 knockdown on the level of metabolites and hypoxia-inducible factor-1α (HIF-1α) protein were determined in GC cells. Oxidative phosphorylation was measured to evaluate adenosine triphosphate (ATP) production.ResultsME3 was downregulated in human GC tissues (P < 0.001). The decreased ME3 mRNA expression was associated with younger age (P = 0.02), pathological staging (P = 0.049), and lymph node metastasis (P = 0.001), while low ME3 expression was associated with tumor size (P = 0.048), tumor invasion depth (P < 0.001), lymph node metastasis (P = 0.018), TNM staging (P < 0.001), and poor prognosis (OS, P = 0.0206; PFS P = 0.0453). ME3 knockdown promoted GC cell malignancy phenotypes. Moreover, α-ketoglutarate (α-KG) and NADPH/NADP+ ratios were reduced while malate was increased in the ME3 knockdown group under normoxia. When cells were incubated under hypoxia, the NADPH/NADP+ ratio and α-KG decreased while intracellular reactive oxygen species (ROS) increased significantly. The ME3 knockdown group exhibited an increase in ATP production and while ME3 overexpression group exhibited oppositely. We discovered that ME3 and HIF-1α expression were negatively correlated in GC cells and tissues, and proposed the hypothesis: downregulation of ME3 promotes GC progression via regulating intracellular oxidative stress and HIF-1α.ConclusionWe provide evidence that ME3 downregulation is associated with poor prognosis in GC patients and propose a hypothesis for the ME3 regulatory mechanism in GC progression. The present study is of great scientific significance and clinical value for exploring the prognostic and therapeutic targets of GC, evaluating and improving the clinical efficacy of patients, reducing recurrence and metastasis, and improving the prognosis and quality of life of patients.

Upregulation of peroxisome proliferator-activated receptor γ with resorcinol alleviates reactive oxygen species generation and lipid accumulation in neuropathic lysosomal storage diseases

Neuropathic lysosomal storage diseases (NLSDs), including ceroid lipofuscinosis neuronal 3 (CLN3) disease and Gaucher disease type 2 (GD2), are typically present in adolescents; however, there are no approved therapies. CLN3 disease is the most common of the 13 types of neuronal ceroid lipofuscinosis, and Gaucher disease is the most common type of lysosomal storage disease. These NLSDs share oxidative stress and lysosomal dysfunction with Parkinson’s disease. In this study, we used patient-derived cells (PDCs) and resorcinol to develop a therapeutic agent based on peroxisome proliferator-activated receptor γ (PPARγ) activation. PPARγ is a major regulator of autophagy and reactive oxygen species (ROS). Resorcinol, a polyphenolic compound, has been reported to exhibit PPARγ agonistic potential. Protein levels were analyzed by immunoblotting and immunofluorescence microscopy. Changes in cellular metabolism, including ROS levels, lipid droplet content, and lysosomal activity, were measured by flow cytometry. Resorcinol reduced ROS levels by suppressing hypoxia-inducible factor 1α levels in CLN3-PDCs. Resorcinol upregulated autophagy and reduced lipid accumulation in CLN3-PDCs; however, these effects were abolished by autophagy inhibitors. Resorcinol increased nuclear PPARγ levels in CLN3-PDCs, and PPARγ antagonists abolished the therapeutic effects of resorcinol. Moreover, Resorcinol upregulated nuclear PPARγ levels and lysosomal activity in GD2-PDCs, and reduced lipid accumulation and ROS levels. In summary, resorcinol alleviated the shared pathogenesis of CLN3 disease and GD2 through PPARγ upregulation. These findings suggest that resorcinol is a potential therapeutic candidate for alleviating NLSD progression.

L-2-Hydroxyglutarate contributes to tumor radioresistance through regulating the hypoxia-inducible factor-1α signaling pathway.

l-2-Hydroxyglutarate (l-2-HG) has been regarded as a tumor metabolite, and it plays a crucial role in adaptation of tumor cells to hypoxic conditions. However, the role of l-2-HG in tumor radioresistance and the underlying mechanism have not yet been revealed. Here, we found that l-2-HG exhibited to have radioresistance effect on U87 human glioblastoma cells, which could reduce DNA damage and apoptosis caused by irradiation, promote cell proliferation and migration, and impair G2/M phase arrest. Mechanistically, l-2-HG upregulated the protein level of hypoxia-inducible factor-1α (HIF-1α) and the expression levels of HIF-1α downstream target genes. The knockdown ofl-2-hydroxyglutarate dehydrogenase(L2HGDH) gene promoted the tumor growth and proliferation of U87 cells in nude mice by increasing HIF-1α expression level in vivo. In addition, the low expression level of L2HGDH gene was correlated with the short survival of patients with glioma or kidney cancer. In conclusion, our study revealed the role and mechanism of l-2-HG in tumor radioresistance and may provide a new perspective for overcoming tumor radioresistance and broaden our comprehension of the role of metabolites in tumor microenvironment.

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.

Effect of the Combined Treatment of Taoren Chengqi Decoction with Laser Photocoagulation on Diabetic Retinopathy

This study investigates the therapeutic effect of the combined treatment of Taoren Chengqi decoction with laser photocoagulation on DR. In animal experiments, A total of 18 rats were used and randomly divided into blank groups, model groups, and treatment groups. The rats in the model group and treatment group were intraperitoneally injected with 60 mg/kg streptozotocin. Moreover, the TCT group was gavaged with Tao-ren Cheng-qi decoction, while the other groups received an equivalent volume of normal saline once daily for 8 weeks. Fasting blood glucose (FBG) and serum interleukin (IL)-6 and IL-1β were determined. In the clinical trial, a total of 80 patients with DR were divided into a laser group (treated with laser photocoagulation) and a combination group (treated with laser photocoagulation+Taoren Chengqi decoction). The central macular thickness (CMT), best-corrected visual acuity (BCVA), and serum levels of high-density lipoprotein cholesterol, low-density-lipoprotein cholesterol, total cholesterol, triglycerides, glycated hemoglobin, and hypoxia-inducible factor 1α were measured in the patients. In animal experiments, we observe that Tao-ren Cheng-qi decoction can effectively reduce the levels of FBG, IL-6, and IL-1β in rats models with DR. Clinical studies revealed that the combination of Taoren Chengqi decoction with laser photocoagulation reduced the levels of blood glucose and lipid-related indices, and improved the inflammatory state, BCVA, and CMT. Therefore, this study suggests that the combined treatment of laser surgery and Taoren Chengqi decoction can be considered an optimal therapeutic approach for patients with DR.

Triple negative breast cancer cells exposed to aryl hydrocarbon receptor ligands hexachlorobenzene and chlorpyrifos activate endothelial cells

Breast cancer is currently one of the most prevalent cancers worldwide. The mechanisms by which pesticides can increase breast cancer risk are multiple and complex. We have previously observed that two aryl hydrocarbon receptor (AhR) agonists ‒pesticides hexachlorobenzene (HCB) and chlorpyrifos (CPF)‒ act on tumor progression, stimulating cell migration and invasion in vitro and tumor growth in animal models. Elevated levels of hypoxia inducible factor-1α (HIF-1α) are found in malignant breast tumors, and HIF-1α is known to induce proangiogenic factors such as vascular endothelial growth factor (VEGF), nitric oxide synthase-2 (NOS-2) and cyclooxygenase-2 (COX-2), which are fundamental in breast cancer progression. In this work, we studied HCB (0.005, 0.05, 0.5 and 5 μM) and CPF (0.05, 0.5, 5 and 50 μM) action on the expression of these proangiogenic factors in triple negative breast cancer cells MDA-MB-231, as well as the effect of their conditioned medium (CM) on endothelial cells. Exposure to pesticides increased HIF-1α and VEGF protein expression in an AhR-dependent manner. In addition, HCB and CPF boosted NOS-2 and COX-2 content and VEGF secretion in MDA-MB-231 cells. The treatment of endothelial cells with CM from tumor cells exposed to pesticides increased cell proliferation, migration, and tubule formation, enhancing both tubule length and branching points. Of note, these effects were VEGF-dependent, as they were blocked in the presence of a VEGF receptor-2 (VEGFR-2) inhibitor. In sum, our results highlight the harmful impact of HCB and CPF in modulating the interaction between breast cancer and endothelial cells and promoting angiogenesis.

GIP attenuates neuronal oxidative stress by regulating glucose uptake in spinal cord injury of rat.

Glucose-dependent insulinotropic polypeptide (GIP) is a ligand of glucose-dependent insulinotropic polypeptide receptor (GIPR) that plays an important role in the digestive system. In recent years, GIP has been regarded as a hormone-like peptide to regulate the local metabolic environment. In this study, we investigated the antioxidant role of GIP on the neuron and explored the possible mechanism. Cell counting Kit-8 (CCK-8) was used to measure cell survival. TdT-mediated dUTP Nick-End Labeling (TUNEL) was used to detect apoptosis invitro and invivo. Reactive oxygen species (ROS) levels were probed with2', 7'-Dichloro dihydrofluorescein diacetate (DCFH-DA), and glucose intake was detected with 2-NBDG. Immunofluorescence staining and western blot were used to evaluate the protein level in cells and tissues. Hematoxylin-eosin (HE) staining, immunofluorescence staining and tract-tracing were used to observe the morphology of the injured spinal cord. Basso-Beattie-Bresnahan (BBB) assay was used to evaluate functional recovery after spinal cord injury. GIP reduced the ROS level and protected cells from apoptosis in cultured neurons and injured spinal cord. GIP facilitated wound healing and functional recovery of the injured spinal cord. GIP significantly improved the glucose uptake of cultured neurons. Meanwhile, inhibition of glucose uptake significantly attenuated the antioxidant effect of GIP. GIP increased glucose transporter 3 (GLUT3) expression via up-regulating the level of hypoxia-inducible factor 1α (HIF-1α) in an Akt-dependent manner. GIP increases GLUT3 expression and promotes glucose intake in neurons, which exerts an antioxidant effect and protects neuronal cells from oxidative stress both invitro and invivo.

Association of Polymorphism with Periodontitis and Salivary Levels of Hypoxia-Inducible Factor-1α.

This investigation aims to investigate the association between HIF-1α genetic polymorphism and periodontitis and examine and contrast the levels of HIF-1α present in the saliva of subjects afflicted with periodontitis and in the control group. Additionally, this study aims to establish diagnostic proficiency of this biomarker in distinguishing between periodontal health and disease. This study entailed the collection of venous blood samples and unstimulated saliva samples from a total of 160 participants, encompassing 80 individuals diagnosed with periodontitis and 80 periodontitis-free individuals. The periodontal parameters were evaluated, involving the measurement of clinical attachment loss, the probing pocket depth, and the bleeding on probing percentage. Subsequently, genetic analysis of HIF-1α using polymerase chain reaction (PCR) technique, DNA sequencing, and enzyme-linked immunosorbent assays was conducted. The genetic analysis of 352 bp of the HIF-1α gene revealed the presence of 66 single-nucleotide polymorphisms (SNPs) in control samples, whereas 78 SNPs were found in periodontitis sample. The nucleotide A was replaced with a C nucleotide at position 207 of the amplified PCR fragments. The homozygous AA pattern was predominant in the control group, with significant differences between the two groups. In contrast, the homozygous CC pattern was more dominant in the periodontitis group, with significant differences between the two groups. The analysis of Hardy-Weinberg equilibrium for the comparison between the observed and the expected genotypes showed significant differences between the observed and the expected values in the control and periodontitis groups, as well as the total sample. The highest mean values of the measured periodontal parameters were found in the periodontitis group (clinical attachment loss = 4.759, probing pocket depth = 4.050, and bleeding on probing = 30.950) with statistically significant differences between the groups. The periodontitis group showed significantly higher salivary HIF-1α levels compared to control group (p < 0.001). Besides, HIF-1α is a good biomarker in distinguishing between periodontal health and periodontitis. rs1951795 SNP of HIF-1α has no significant impact on the progression of periodontitis and the salivary level HIF-1α. Periodontitis results in a notable elevation in HIF-1α salivary levels, with an outstanding diagnostic ability to distinguish between periodontitis and periodontal health.

Elevated aerobic glycolysis driven by p62-mTOR axis promotes arsenic-induced oncogenic phenotypes in human mammary epithelial cells.

Chronic arsenic exposure is considered to increase the risk of breast cancer. p62 is a multifunctional adaptor protein that controls myriad cellular processes and is overexpressed in breast cancer tissues. Although previous studies have indicated the involvement of p62 accumulation in arsenic tumorigenesis, the underlying mechanism remains obscure. Here, we found that 0.1 µM or 0.5 µM arsenite exposure for 24 weeks induced oncogenic phenotypes in human mammary epithelial cells. Elevated aerobic glycolysis, cell proliferation capacity, and activation of p62-mTOR pathway, as indicated by increased protein levels of p62, phosphorylated-mTOR (p-mTOR) and hypoxia-inducible factor 1α (HIF1α), were observed in chronically arsenite-exposed cells, and of note in advance of the onset of oncogenic phenotypes. Moreover, p62 silencing inhibited acquisition of oncogenic phenotypes in arsenite-exposed cells. The protein levels of p-mTOR and HIF1α, as well as aerobic glycolysis and cell proliferation, were suppressed by p62 knockdown. In addition, re-activation of p‑mTOR reversed the inhibitory effects of p62 knockdown. Collectively, our data suggest that p62 exerts an oncogenic role via mTORC1 activation and acts as a key player in glucose metabolism during arsenite-induced malignant transformation, which provides a new mechanistic clue for the arsenite carcinogenesis.

To observe the clinical effect of lipoic acid combined with continuous positive airway pressure ventilation in treating obstructive sleep apnea-hypopnea syndrome and its effect on peripheral blood γ-aminobutyric acid and melatonin levels.

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a common respiratory disease with potential lethality. At present, the commonly used treatment method is continuous positive airway pressure ventilation, but with the prolongation of the course of the disease, the effect of single ventilation on the improvement of oxidative stress levels is not good. Lipoic acid is a commonly used antioxidant in clinics. In this paper, lipoic acid combined with continuous positive airway pressure ventilation is used to explore whether it has a better therapeutic effect on patients. To probe into the clinical efficacy of lipoic acid combined with continuous positive airway pressure ventilation in the therapy of OSAHS. 82 patients with OSAHS who were cured in our hospital from March 2021 to September 2022 were prospectively collected as subjects. Based on different treatment methods, patients were grouped into a control group (43 cases) and an observation group (39 cases). The control group was treated with continuous positive airway pressure (CPAP), and the observation group was treated with lipoic acid based on control group. The therapeutic effects were measuredby apnea hypopnea index (AHI), oxygen saturation (SpO2), mean oxygen saturation (MSpO2), serum malondialdehyde (MDA), superoxide dismutase (SOD), hypoxia inducible factor-1α (HIF-1α) levels, peripheral blood γ-aminobutyric acid, melatonin levels. The clinical effectiveness of the observation group was better (P < 0.05). After treatment, AHI, the levels of MDA and HIF-1α in the observation group were lower and SpO2, MSpO2 and the level of SOD, γ- aminobutyric acid, and melatonin were higher than those in the control group (P < 0.05). The levels of γ- aminobutyric acid and melatonin were negatively correlated with the severity of symptoms, ESS, and AIS scores (P < 0.05). The clinical effect of lipoic acid combined with CPAP in the treatment of OSAHS is better, and it has a positive effect on the levels of γ-aminobutyric acid and melatonin in peripheral blood. Lipoic acid was added to the original method for treatment, and the therapeutic effect was greatly improved.