Pulmonary hypertension (PH) is a heterogeneous and life-threatening cardiopulmonary disorder in which mitochondrial dysfunction is believed to drive pathogenesis, although the underlying mechanisms remain unclear. To determine if abnormal SIRT3 (sirtuin 3) activity is related to mitochondrial dysfunction in adventitial fibroblasts from patients with idiopathic pulmonary arterial hypertension (IPAH) and hypoxic PH calves (PH-Fibs) and whether SIRT3 could be a potential therapeutic target to improve mitochondrial function, SIRT3 concentrations in control fibroblasts, PH-Fibs, and lung tissues were determined using quantitative real-time PCR and western blot. SIRT3 deacetylase activity in cells and lung tissues was determined using western blot, immunohistochemistry staining, and immunoprecipitation. Glycolysis and mitochondrial function in fibroblasts were measured using respiratory analysis and fluorescence-lifetime imaging microscopy. The effects of restoring SIRT3 activity (by overexpression of SIRT3 with plasmid, activation SIRT3 with honokiol, and supplementation with the SIRT3 cofactor nicotinamide adenine dinucleotide [NAD+]) on mitochondrial protein acetylation, mitochondrial function, cell proliferation, and gene expression in PH-Fibs were also investigated. We found that SIRT3 concentrations were decreased in PH-Fibs and PH lung tissues, and its cofactor, NAD+, was also decreased in PH-Fibs. Increased acetylation in overall mitochondrial proteins and SIRT3-specific targets (MPC1 [mitochondrial pyruvate carrier 1] and MnSOD2 [mitochondrial superoxide dismutase]), as well as decreased MnSOD2 activity, was identified in PH-Fibs and PH lung tissues. Normalization of SIRT3 activity, by increasing its expression with plasmid or with honokiol and supplementation with its cofactor NAD+, reduced mitochondrial protein acetylation, improved mitochondrial function, inhibited proliferation, and induced apoptosis in PH-Fibs. Thus, our study demonstrated that restoration of SIRT3 activity in PH-Fibs can reduce mitochondrial protein acetylation and restore mitochondrial function and PH-Fib phenotype in PH.

• MeSH
• fibroblasty metabolismus   MeSH
• lidé MeSH
• mitochondriální proteiny metabolismus   MeSH
• mitochondrie metabolismus   MeSH
• NAD metabolismus   MeSH
• plicní hypertenze * patologie   MeSH
• sirtuin 3 * genetika   metabolismus   MeSH
• skot MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

S28463 (S28), a ligand for Toll-like receptor 7/8, has been shown to have antiinflammatory properties in rodent models of allergic asthma. The principle goal of this study was to assess whether these antiinflammatory effects can also be observed in a nonhuman primate (NHP) model of allergic asthma. NHPs were sensitized then challenged with natural allergen, Ascaris suum extract. The animals were treated with S28 orally before each allergen challenge. The protective effect of S28 in NHPs was assessed by measuring various asthma-related phenotypes. We also characterized the metabolomic and proteomic signatures of the lung environment and plasma to identify markers associated with the disease and treatment. Our data demonstrate that clinically relevant parameters, such as wheal and flare response, blood IgE levels, recruitment of white blood cells to the bronchoalveolar space, and lung responsiveness, are decreased in the S28-treated allergic NHPs compared with nontreated allergic NHPs. Furthermore, we also identified markers that can distinguish allergic from nonallergic or allergic and drug-treated NHPs, such as metabolites, phosphocreatine and glutathione, in the plasma and BAL fluid, respectively; and inflammatory cytokines, IL-5 and IL-13, in the bronchoalveolar lavage fluid. Our preclinical study demonstrates that S28 has potential as a treatment for allergic asthma in primate species closely related to humans. Combined with our previous findings, we demonstrate that S28 is effective in different models of asthma and in different species, and has the antiinflammatory properties clinically relevant for the treatment of allergic asthma.

• MeSH
• alergeny toxicita   MeSH
• Ascaris suum chemie   imunologie   MeSH
• bronchiální astma * chemicky indukované   imunologie   patologie   MeSH
• interleukin-13 imunologie   MeSH
• interleukin-5 imunologie   MeSH
• Macaca fascicularis MeSH
• proteiny červů toxicita   MeSH
• toll-like receptor 7 * agonisté   imunologie   MeSH
• toll-like receptor 8 * agonisté   imunologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Obstructive sleep apnea (OSA) is associated with insulin resistance, glucose intolerance, and type 2 diabetes. Causal mechanisms mediating this association are not well defined; however, augmented lipolysis in adipose might be involved. Here, we investigated the effect of acipimox treatment (lipolysis inhibitor) on glucose tolerance and insulin sensitivity in mice exposed to intermittent hypoxia (IH). C57BL6/J mice were exposed for 14 days to IH or control conditions. IH was created by decreasing the fraction of inspired oxygen from 20.9 to 6.5%, 60 times/h. Control exposure was air (fraction of inspired oxygen, 20.9%) delivered at an identical flow rate. Acipimox was provided in drinking water (0.5 g/ml) during exposures. After exposures, intraperitoneal insulin (0.5 IU/kg) and glucose (1 g/kg) tolerance tests were performed, and primary adipocytes were isolated for lipolysis experiments. IH elevated fasting glucose by 51% and worsened glucose tolerance and insulin sensitivity by 33 and 102%, respectively. In parallel, IH increased spontaneous lipolysis by 264%, and reduced epididymal fat mass by 15% and adipocyte size by 8%. Acipimox treatment prevented IH-induced lipolysis and increased epididymal fat mass and adipocyte size by 19 and 10%, respectively. Acipimox fully prevented IH-induced impairments in fasting glycemia, glucose tolerance, and insulin sensitivity. For all reported results, P less than 0.05 was considered significant. Augmented lipolysis contributes to insulin resistance and glucose intolerance observed in mice exposed to IH. Acipimox treatment ameliorated the metabolic consequences of IH and might represent a novel treatment option for patients with obstructive sleep apnea.

• MeSH
• adipozita účinky léků   MeSH
• experimentální diabetes mellitus krev   komplikace   genetika   patologie   MeSH
• fenotyp MeSH
• glukosa metabolismus   MeSH
• hypoxie komplikace   metabolismus   MeSH
• inzulin metabolismus   MeSH
• lipolýza * účinky léků   MeSH
• mastné kyseliny krev   MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední C57BL MeSH
• obstrukční spánková apnoe krev   komplikace   genetika   patologie   MeSH
• pyraziny farmakologie   MeSH
• regulace genové exprese účinky léků   MeSH
• signální transdukce účinky léků   MeSH
• tukové buňky účinky léků   patologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Remodeling of the distal pulmonary artery wall is a characteristic feature of pulmonary hypertension (PH). In hypoxic PH, the most substantial pathologic changes occur in the adventitia. Here, there is marked fibroblast proliferation and profound macrophage accumulation. These PH fibroblasts (PH-Fibs) maintain a hyperproliferative, apoptotic-resistant, and proinflammatory phenotype in ex vivo culture. Considering that a similar phenotype is observed in cancer cells, where it has been associated, at least in part, with specific alterations in mitochondrial metabolism, we sought to define the state of mitochondrial metabolism in PH-Fibs. In PH-Fibs, pyruvate dehydrogenase was markedly inhibited, resulting in metabolism of pyruvate to lactate, thus consistent with a Warburg-like phenotype. In addition, mitochondrial bioenergetics were suppressed and mitochondrial fragmentation was increased in PH-Fibs. Most importantly, complex I activity was substantially decreased, which was associated with down-regulation of the accessory subunit nicotinamide adenine dinucleotide reduced dehydrogenase (ubiquinone) Fe-S protein 4 (NDUFS4). Owing to less-efficient ATP synthesis, mitochondria were hyperpolarized and mitochondrial superoxide production was increased. This pro-oxidative status was further augmented by simultaneous induction of cytosolic nicotinamide adenine dinucleotide phosphate reduced oxidase 4. Although acute and chronic exposure to hypoxia of adventitial fibroblasts from healthy control vessels induced increased glycolysis, it did not induce complex I deficiency as observed in PH-Fibs. This suggests that hypoxia alone is insufficient to induce NDUFS4 down-regulation and constitutive abnormalities in complex I. In conclusion, our study provides evidence that, in the pathogenesis of vascular remodeling in PH, alterations in fibroblast mitochondrial metabolism drive distinct changes in cellular behavior, which potentially occur independently of hypoxia.

• MeSH
• buněčné dýchání MeSH
• chronická nemoc MeSH
• citrátový cyklus MeSH
• down regulace MeSH
• energetický metabolismus MeSH
• fenotyp MeSH
• fibroblasty metabolismus   MeSH
• glykolýza MeSH
• hypoxie komplikace   patologie   MeSH
• kyselina pyrohroznová metabolismus   MeSH
• lidé MeSH
• makrofágy metabolismus   MeSH
• mitochondrie metabolismus   MeSH
• oxidace-redukce MeSH
• oxidativní fosforylace MeSH
• parakrinní signalizace MeSH
• plíce patologie   MeSH
• plicní hypertenze komplikace   metabolismus   patologie   MeSH
• přeprogramování buněk * MeSH
• pyruvátdehydrogenasový komplex metabolismus   MeSH
• respirační komplex I metabolismus   MeSH
• skot MeSH
• superoxidy metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Genetic factors, in particular human leukocyte antigens (HLAs) are important determinants of susceptibility to sarcoidosis, a chronic granulomatous disease of undetermined etiology. To clarify the role of HLA in sarcoidosis we determined HLA-DR and -DQ alleles in case-control samples from three European populations (United Kingdom, Czech, and Polish) and compared these results with those published for three additional populations (Italian, Japanese, and Scandinavian) to determine whether the HLA-DR and/or -DQ alleles act as ethnic-dependent, or ethnic-independent modifiers of disease risk. Although variations were apparent in the alleles associated with susceptibility, reductions in the frequency of alleles associated with protection were remarkably consistent in the six populations. Previously detected associations between single-nucleotide polymorphisms at the TAP2 locus and sarcoidosis were shown to be due to linkage disequilibrium with the HLA-DR locus. The protective HLA-DR alleles, which encode the DR1 and DR4 antigens, were found to share characteristic small hydrophobic residues at position 11, which were replaced by small hydrophilic residues in the remaining, nonprotective, HLA-DR alleles. This residue position is within a pocket of the HLA-DR complex antigen binding groove (designated P6), where it is the only variable amino acid and therefore determines the peptide binding preferences of this pocket. A highly significant reduction in the frequency of individuals carrying HLA-DR alleles with a hydrophobic residue at position 11 was observed in the sarcoidosis cases in the three populations we examined. This suggests this HLA-DR residue is an important protective marker in sarcoidosis.

• MeSH
• ABC transportér podrodiny B, člen 3 MeSH
• ABC transportéry genetika   MeSH
• alely MeSH
• dospělí MeSH
• genetické markery MeSH
• genotyp MeSH
• geny MHC třídy II * MeSH
• HLA-DR antigeny chemie   genetika   MeSH
• HLA-DRB1 řetězec MeSH
• lidé středního věku MeSH
• lidé MeSH
• plicní sarkoidóza etnologie   genetika   imunologie   patofyziologie   MeSH
• studie případů a kontrol MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Polsko MeSH
• Spojené království MeSH