Restricted Activation of the NF-κB Pathway in Individuals with Latent Tuberculosis Infection after HIF-1α Blockade.

Tuberculous granuloma formation is mediated by hypoxia-inducible factor 1 alpha (HIF-1α), and is essential for establishing latent tuberculosis infection (LTBI) and its progression to active tuberculosis (TB). Here, we investigated whether HIF-1α expression and adjacent mechanisms were associated with latent or active TB infection. Patients with active TB, individuals with LTBI, and healthy controls were recruited, and the expression of cytokine genes IL15, IL18, TNFA, IL6, HIF1A, and A20 in peripheral blood mononuclear cells (PBMCs) and serum vitamin D (25(OH)D3) levels were evaluated. Additionally, nuclear factor kappa B (NF-κB) and tumor necrosis factor-alpha (TNF-α) levels were analyzed in PBMC lysates and culture supernatants, respectively, after HIF-1α blockade with 2-methoxyestradiol. We observed that IL-15 expression was higher in individuals with LTBI than in patients with active TB, while IL-18 and TNF-α expression was similar between LTBI and TB groups. Additionally, serum 25(OH)D3 levels and expression of IL-6, HIF1A, and A20 were higher in patients with active TB than in individuals with LTBI. Moreover, PBMCs from individuals with LTBI showed decreased NF-κB phosphorylation and increased TNF-α production after HIF-1α blockade. Together, these results suggest that under hypoxic conditions, TNF-α production and NF-κB pathway downregulation are associated with the LTBI phenotype.

Effects of moderate-intensity intermittent hypoxic training on health outcomes of patients recovered from COVID-19: the AEROBICOVID study protocol for a randomized controlled trial.

BACKGROUND: Recent studies point to a lower number and reduced severity of cases in higher altitude cities with decreased oxygen concentration. Specific literature has shown several benefits of physical training, so, in this sense, physical training with hypoxic stimulus appears as an alternative that supports the conventional treatments of the COVID-19 patient's recovery. Thus, this study's primary aim is to analyze the effects of moderate-intensity intermittent hypoxic training on health outcomes in COVID-19 recovered patients. METHODS: A clinical trial controlled double-blind study was designed. Participants (30-69 years old) will be recruited among those with moderate to severe COVID-19 symptoms, approximately 30 days after recovery. They will be included in groups according to the training (T) and recovery (R) association with hypoxia (H) or normoxia (N): (a) TH:RH, (b) TN:RH, (c) TN:RN, and last (d) the control group. The 8-week exercise bike intervention will be carried out with a gradual load increase according to the established periods, three times a week in sets of 5 min, 90 to 100% of the anaerobic threshold (AT), and a 2.5-min break. Blood will be collected for genotyping. First, after 4 weeks (partial), after 8 weeks, and later, 4 weeks after the end of the physical training intervention, participants will perform assessments. The primary outcome is the maximum oxygen consumption (VO2peak). The secondary outcomes include lung function, inflammatory mediators, hematological, autonomic parameters, AT, body composition analysis, quality of life, mental health, anthropometric measurements, and physical fitness. The statistical analysis will be executed using the linear regression model with mixed effects at a 5% significance level. DISCUSSION: This study is designed to provide evidence to support the clinical benefits of moderate-intensity intermittent hypoxic training as a part of the treatment of patients recovered from COVID-19. It may also provide evidence on the efficacy and safety of intermittent hypoxic training in different health conditions. Lastly, this study presents an innovative strategy enabling up to 16 participants in the same training session. TRIAL REGISTRATION: ClinicalTrials.gov RBR-5d7hkv. Registered after the start of inclusion on 3 November 2020 with the Brazilian Clinical Trials Registry.

Effects of Qualea grandiflora Extract on the Expression of MMP-14 and HIF-1α in Cultured Fibroblasts and Preosteoblasts

Abstract Background: Qualea grandiflora (QG) (Vochysiaceae), also known as "pau-ferro", "pau-terra" or "pau-de-tucano", is a very common deciduous tree in the Brazilian Cerrado used in traditional medicine to treat inflammations, ulcers, diarrhea, and infections. There are reports in the scientific literature that demonstrate the medicinal effects of the bark and leaf of the QG. However, studies involving this plant are rather imited. Aim of the study: To perform the phytochemical analysis of the QG hydroalcoholic extract (HAE) of leaves, and to investigate it effects on fibroblast and preosteoblasts. Methods: Phytochemical analysis was done by HPLC-DAD. Murine NIH/3T3 fibroblasts and MC3T3-E1 preosteoblasts cell lines (ATCC) were used for the experiments. Cell viability was assessed by the MTT colorimetric assay and the expression of MMP-14 and HIF-1α by immunofluorescence. Results and conclusion: The following compounds were identified by HPLC-DAD, such as quinic acid, ethyl galate, ellagic acid derivatives as O-methylellagic acid O-galloyl, O-methylellagic acid O-deoxyhexoside, galloyl derivatives, flavonol glycoside as kaempferol-O-deoxyhexoside, quercetin-O-deoxyhexoside, myricetin-O-deoxyhexoside and the pentacyclic triterpene arjunglucoside. Cell viability results demonstrated no cytotoxic effects in the studied concentrations. We found in QG HAE some compounds with therapeutic properties that can increase the expression of MMP-14 and HIF-1α, in fibroblasts and preosteoblasts. These data suggest that QG HAE has an action on these two molecules widely involved in physiological conditions, such as collagen remodeling, bone development and growth and pathological processes as HIF signaling in cancer metastasis.

Effect of intramuscular baculovirus encoding mutant hypoxia-inducible factor 1-alpha on neovasculogenesis and ischemic muscle protection in rabbits with peripheral arterial disease.

BACKGROUND AIMS: Peripheral arterial disease (PAD) is a progressive, disabling ailment for which no effective treatment exists. Gene therapy-mediated neovascularization has emerged as a potentially useful strategy. We tested the angiogenic and arteriogenic efficacy and safety of a baculovirus (BV) encoding mutant, oxygen-resistant hypoxia-inducible factor 1-alpha (mHIF-1α), in rabbits with PAD. METHODS: After assessing the transfection efficiency of the BV.mHIF-1α vector and its tubulogenesis potential in vitro, we randomized rabbits with experimental PAD to receive 1 × 109 copies of BV.mHIF-1α or BV.null (n = 6 per group) 7 days after surgery. Two weeks post-treatment, collateralization (digital angiography) and capillary and arteriolar densities (immunohistochemistry) were measured in the posterior limbs. Ischemic damage was evaluated in adductor and gastrocnemius muscle samples. Tracking of viral DNA in injected zones and remote tissues at different time points was performed in additional rabbits using a BV encoding GFP. RESULTS: Angiographically visible collaterals were more numerous in BV.mHIF-1α-treated rabbits (8.12 ± 0.42 vs 6.13 ± 1.15 collaterals/cm2, P < 0.05). The same occurred with arteriolar (27.9 ± 7.0 vs 15.3 ± 4.0 arterioles/mm2) and capillary (341.8 ± 109.9 vs 208.8 ± 87.7 capillaries/mm2, P < 0.05) densities. BV.mHIF-1α-treated rabbits displayed less ischemic muscle damage than BV.null-treated animals. Viral DNA and GFP mRNA were detectable only at 3 and 7 days after injection in hind limbs. Neither the virus nor GFP mRNA was detected in remote tissues. CONCLUSIONS: In rabbits with PAD, BV.mHIF-1α induced neovascularization and reduced ischemic damage, exhibiting a good safety profile at 14 days post-treatment. Complementary studies to evaluate its potential usefulness in the clinic are needed.

HIF-1α Levels in patients receiving chemoradiotherapy for locally advanced non-small cell lung carcinoma

SUMMARY AIM To examine the relationship between treatment response and hypoxia-inducible factor-1 alpha (HIF-1α) levels in patients with locally advanced non-small cell lung cancer (NSCLC) who received chemoradiotherapy (CRT). METHODS Eighty patients with NSCLC were included in the study and treated at Acibadem Mehmet Ali Aydınlar University Medical Faculty. HIF-1 α levels were measured before and after CRT by the enzyme-linked immunosorbent assay (ELISA) method. RESULTS Patients' stages were as follows; stage IIIA (65%) and stage IIIB (35%). Squamous histology was 45%, adenocarcinoma was 44%, and others were 11%. Chemotherapy and radiotherapy were given concurrently to 80 patients. Forty-five (56%) patients received cisplatin-based chemotherapy, and 35 (44%) received carboplatin-based chemotherapy. Serum HIF-1α levels (42.90 ± 10.55 pg/mL) after CRT were significantly lower than the pretreatment levels (63.10 ± 10.22 pg/mL, p<0.001) in patients with locally advanced NSCLC. CONCLUSION The results of this study revealed that serum HIF-1α levels decreased after CRT. Decrease of HIF-1α levels after the initiation of CRT may be useful for predicting the efficacy of CRT.

RESUMO OBJETIVO Examinar a relação entre a resposta ao tratamento e os níveis de fator 1 induzida por hipóxia (HIF-1α) em pacientes com câncer de pulmão de células não pequenas localmente avançado (NSCLC) que receberam quimiorradioterapia (CRT). MÉTODO Oitenta pacientes com NSCLC foram incluídos no estudo e foram tratados na Faculdade de Medicina da Acibadem Mehmet Ali Aydınlar University. O nível de HIF-1α foi medido antes e depois da TRC pelo método de ensaio imunoenzimático (ELISA). RESULTADOS Os estágios dos pacientes foram os seguintes; estágio IIIA (65%) e estágio IIIB (35%). A histologia escamosa foi de 45%, o adenocarcinoma de 44% e o outro de 11%. Quimioterapia e radioterapia foram dadas simultaneamente a 80 pacientes. Quarenta e cinco (56%) pacientes receberam quimioterapia à base de cisplatina e 35 (44%) receberam quimioterapia à base de carboplatina. Os níveis séricos de HIF-1α (42,90 ± 10,55 pg / mL) após a TRC foram significativamente menores do que os níveis pré-tratamento (63,10 ± 10,22 pg / mL, p <0,001) em pacientes com NSCLC localmente avançado. CONCLUSÃO Os resultados deste estudo revelaram que os níveis séricos de HIF-1α diminuíram após a TRC. A diminuição dos níveis de HIF-1α após o início da TRC pode ser útil para prever a eficácia da TRC.

Induction of HIF-1α by HIV-1 Infection in CD4+ T Cells Promotes Viral Replication and Drives Extracellular Vesicle-Mediated Inflammation.

Chronic immune activation and inflammation are hallmarks of HIV-1 infection and a major cause of serious non-AIDS events in HIV-1-infected individuals on antiretroviral treatment (ART). Herein, we show that cytosolic double-stranded DNA (dsDNA) generated in infected CD4+ T cells during the HIV-1 replication cycle promotes the mitochondrial reactive oxygen species (ROS)-dependent stabilization of the transcription factor hypoxia-inducible factor 1α (HIF-1α), which in turn, enhances viral replication. Furthermore, we show that induction of HIF-1α promotes the release of extracellular vesicles (EVs). These EVs foster inflammation by inducing the secretion of gamma interferon by bystander CD4+ T cells and secretion of interleukin 6 (IL-6) and IL-1ß by bystander macrophages through an HIF-1α-dependent pathway. Remarkably, EVs obtained from plasma samples from HIV-1-infected individuals also induced HIF-1α activity and inflammation. Overall, this study demonstrates that HIF-1α plays a crucial role in HIV-1 pathogenesis by promoting viral replication and the release of EVs that orchestrate lymphocyte- and macrophage-mediated inflammatory responses.IMPORTANCE Human immunodeficiency virus type 1 (HIV-1) is a very important global pathogen that preferentially targets CD4+ T cells and causes acquired immunodeficiency syndrome (AIDS) if left untreated. Although antiretroviral treatment efficiently suppresses viremia, markers of immune activation and inflammation remain higher in HIV-1-infected patients than in uninfected individuals. The hypoxia-inducible factor 1α (HIF-1α) is a transcription factor that plays a fundamental role in coordinating cellular metabolism and function. Here we show that HIV-1 infection induces HIF-1α activity and that this transcription factor upholds HIV-1 replication. Moreover, we demonstrate that HIF-1α plays a key role in HIV-1-associated inflammation by promoting the release of extracellular vesicles which, in turn, trigger the secretion of inflammatory mediators by noninfected bystander lymphocytes and macrophages. In summary, we identify that the coordinated actions of HIF-1α and extracellular vesicles promote viral replication and inflammation, thus contributing to HIV-1 pathogenesis.

Oxidative stress and mitochondrial dysfunction-linked neurodegenerative disorders.

Reactive species play an important role in physiological functions. Overproduction of reactive species, notably reactive oxygen (ROS) and nitrogen (RNS) species along with the failure of balance by the body's antioxidant enzyme systems results in destruction of cellular structures, lipids, proteins, and genetic materials such as DNA and RNA. Moreover, the effects of reactive species on mitochondria and their metabolic processes eventually cause a rise in ROS/RNS levels, leading to oxidation of mitochondrial proteins, lipids, and DNA. Oxidative stress has been considered to be linked to the etiology of many diseases, including neurodegenerative diseases (NDDs) such as Alzheimer diseases, Amyotrophic lateral sclerosis, Friedreich's ataxia, Huntington's disease, Multiple sclerosis, and Parkinson's diseases. In addition, oxidative stress causing protein misfold may turn to other NDDs include Creutzfeldt-Jakob disease, Bovine Spongiform Encephalopathy, Kuru, Gerstmann-Straussler-Scheinker syndrome, and Fatal Familial Insomnia. An overview of the oxidative stress and mitochondrial dysfunction-linked NDDs has been summarized in this review.

The HIF1A rs2057482 polymorphism is associated with risk of developing premature coronary artery disease and with some metabolic and cardiovascular risk factors. The Genetics of Atherosclerotic Disease (GEA) Mexican Study.

The aim of the present study was to establish the role of HIF1A gene polymorphisms in the risk of developing premature coronary artery disease (CAD) in a well-characterized clinical cohort. Three polymorphisms in HIF1A (rs11549465, rs11549467, rs2057482) gene were genotyped in 949 patients with premature CAD, and 676 healthy controls (with negative calcium score by computed tomography). Under a dominant model adjusted for age, visceral to subcutaneous adipose tissue (VAT/SAT) ratio, hypertension, type 2 diabetes mellitus (T2DM), HDL-C levels, hypercholesterolemia and hypertriglyceridemia, the rs2057482 T allele was associated with decreased risk of premature CAD when compared to healthy controls (OR = 0.616, P(dom) = 0.020). The effect of the studied polymorphisms on various metabolic parameters and cardiovascular risk factors was explored. In this analysis, the rs2057482 T allele was associated with decreased risk of obesity, central obesity, hypertension, hypercholesterolemia, hypertriglyceridemia and increased risk of T2DM. Under a dominant model adjusted by age, the HIF1A rs2057482 T polymorphism was associated with high VAT/SAT ratio (P = 0.009) and HDL-C levels (P = 0.04) in healthy controls. The results suggest that HIF1A rs2057482 polymorphism is involved in the risk of developing CAD and is associated with some metabolic parameters and cardiovascular risk factors.