The World Health Organization has identified studies of the role of host genetics on susceptibility to severe influenza as a priority. A systematic review was conducted to summarize the current state of evidence on the role of host genetics in susceptibility to influenza (PROSPERO registration number: CRD42011001380). PubMed, Web of Science, the Cochrane Library, and OpenSIGLE were searched using a pre-defined strategy for all entries up to the date of the search. Two reviewers independently screened the title and abstract of 1,371 unique articles, and 72 full text publications were selected for inclusion. Mouse models clearly demonstrate that host genetics plays a critical role in susceptibility to a range of human and avian influenza viruses. The Mx genes encoding interferon inducible proteins are the best studied but their relevance to susceptibility in humans is unknown. Although the MxA gene should be considered a candidate gene for further study in humans, over 100 other candidate genes have been proposed. There are however no data associating any of these candidate genes to susceptibility in humans, with the only published study in humans being under-powered. One genealogy study presents moderate evidence of a heritable component to the risk of influenza-associated death, and while the marked familial aggregation of H5N1 cases is suggestive of host genetic factors, this remains unproven. The fundamental question “Is susceptibility to severe influenza in humans heritable?” remains unanswered. Not because of a lack of genotyping or analytic tools, nor because of insufficient severe influenza cases, but because of the absence of a coordinated effort to define and assemble cohorts of cases. The recent pandemic and the ongoing epizootic of H5N1 both represent rapidly closing windows of opportunity to increase understanding of the pathogenesis of severe influenza through multi-national host genetic studies.
27 August 2013 in Influenza and Other Respiratory Viruses
The development of therapeutics for muscle diseases such as facioscapulohumeral dystrophy (FSHD) is impeded by a lack of objective, minimally invasive biomarkers. Here we identify circulating miRNAs and proteins that are dysregulated in early-onset FSHD patients to develop blood-based molecular biomarkers. Plasma samples from clinically characterized individuals with early-onset FSHD provide a discovery group and are compared to healthy control volunteers. Low-density quantitative polymerase chain reaction (PCR)-based arrays identify 19 candidate miRNAs, while mass spectrometry proteomic analysis identifies 13 candidate proteins. Bioinformatic analysis of chromatin immunoprecipitation (ChIP)-seq data shows that the FSHD-dysregulated DUX4 transcription factor binds to regulatory regions of several candidate miRNAs. This panel of miRNAs also shows ChIP signatures consistent with regulation by additional transcription factors which are up-regulated in FSHD (FOS, EGR1, MYC, and YY1). Validation studies in a separate group of patients with FSHD show consistent up-regulation of miR-100, miR-103, miR-146b, miR-29b, miR-34a, miR-454, miR-505, and miR-576. An increase in the expression of S100A8 protein, an inflammatory regulatory factor and subunit of calprotectin, is validated by Enzyme-Linked Immunosorbent Assay (ELISA). Bioinformatic analyses of proteomics and miRNA data further support a model of calprotectin and toll-like receptor 4 (TLR4) pathway dysregulation in FSHD. Moving forward, this panel of miRNAs, along with S100A8 and calprotectin, merit further investigation as monitoring and pharmacodynamic biomarkers for FSHD.
1 January 2020 in Applied Physiology, Nutrition, and Metabolism
Ketogenic diets (KDs) are shown to benefit hepatic metabolism; however, their effect on the liver when combined with exercise is unknown. We investigated the effects of a KD versus a “western” diet (WD) on markers of hepatic lipid metabolism and oxidative stress in exercising rats. Male and female Wistar rats with access to voluntary running wheels were randomized to 3 groups (n = 8–14 per group): standard chow (SC; 17% fat), WD (42% fat), or KD (90.5% fat) for 7 weeks. Body fat percentage (BF%) was increased in WD and KD versus SC, although KD females displayed lower BF% versus WD (p ≤ 0.05). Liver triglycerides were higher in KD and WD versus SC but were attenuated in KD females versus WD (p ≤ 0.05). KD suppressed hepatic markers of de novo lipogenesis (fatty acid synthase, acetyl coenzyme A carboxylase) and increased markers of mitochondrial biogenesis/content (peroxisome proliferator activated receptor-1α, mitochondrial transcription factor A (TFAM), and citrate synthase activity). KD also increased hepatic glutathione peroxidase 1 and lowered oxidized glutathione. Female rats exhibited elevated hepatic markers of mitochondrial biogenesis (TFAM), mitophagy (light chain 3 II/I ratio, autophagy-related protein 12:5), and cellular energy homeostasis (phosphorylated 5′AMP-activated protein kinase/5′AMP-activated protein kinase) versus males. These data highlight that KD and exercise beneficially impacts hepatic metabolism and oxidative stress and merits further investigation. Novelty KD feeding combined with exercise improved hepatic oxidative stress, suppressed markers of de novo lipogenesis, and increased markers of mitochondrial content versus WD feeding. Males and females responded similarly to combined KD feeding and exercise. Female rats exhibited elevated hepatic markers of autophagy/mitophagy and energy homeostasis compared with male rats.
The methanol extracts of nine popular cultivated Vietnamese rice cultivars (Oryza sativa L.cv. OM 2395, 5451, 6976, 380, 5930, 4498, 3536, N406, and 7347) were used to explore their allelopathic potential on barnyardgrass (Echinochola crus-galli L.). At 0.1 g mL−1, OM 5930, OM 4498, and OM 6976 correlatively possessed greatest phytotoxicity on barnyardgrass shoot (98.77%, 90.75%, and 87.17%) and root (99.39%, 92.83%, and 86.56%) growth. The following study aimed to detect previously-known allelochemicals in those rice using XCMS online cloud-based metabolomics platform. Twenty allelochemicals were semi-quantified and seven of them were detected predominantly and five was putatively confirmed in OM 5930 (mg/ 100g fresh rice) as salicylic acid (5.0076), vanillic acid (0.1246), p-coumaric acid (0.1590), 2,4-dimethoxybenzoic acid (0.1045), and cinnamic acid (3.3230). These compounds were active at concentrations greater than 0.5 mM and the average EC50 were 1.24 mM. The results indicated that OM 5930 may use as promising candidates in weed biological control for rice production.
Introduction: Whole body loss of endothelial nitric oxide synthase (eNOS) worsens hepatic mitochondrial function and exacerbates nonalcoholic fatty liver disease (NAFLD) development and progression. However, the precise role of eNOS in hepatocytes in the contribution to NAFLD has not been established. Here, we examine the effects of in vivo hepatocyte‐specific ablation of eNOS on hepatic steatosis and NAFLD susceptibility. Methods: Hepatocyte‐specific eNOS knockout ( eNOShep−/−) mice were generated by crossing homozygous eNOS floxed ( eNOSfl/fl ) mice on a C57/BL6J background with albumin‐Cre recombinase transgenic mice. At 10 weeks of age, male eNOSfl/fl and eNOShep−/− mice ( n = 12–14) were fed a control diet (10% fat) for 16 weeks. Results: Body weight, body fat, and food intake did not differ between eNOSfl/fl and eNOShep−/− mice. eNOShep−/− mice developed elevated histological hepatic steatosis and increased fasting serum insulin (~30%) compared to eNOSfl/fl mice (p<0.05), along with trends for elevations in serum liver enzymes AST and ALT (p<0.17). Elevated hepatic steatosis in eNOShep−/− was related to significant reductions (−50%) in hepatic mitochondrial fatty acid oxidation and ADP‐stimulated and maximal uncoupled hepatic mitochondrial respiration (p<0.05). However, hepatic citrate synthase activity, a marker of mitochondrial mass, was significantly elevated in eNOShep−/− mice compared to eNOSfl/fl mice (p<0.05), while protein content of oxidative phosphorylation complexes and peroxisome proliferator‐activated receptor‐γ coactivator‐1α (PGC‐1α) did not differ between groups. Furthermore, eNOShep−/− mice presented with significant reductions (p<0.05) in key proteins involved in mitophagy and autophagy including PTEN‐induced kinase 1 (PINK1) and phosphorylated Unc‐51 Like Autophagy Activating Kinase 1 (pUlk1/Ulk1) and tended to have significant reductions in BCL2/adenovirus E1B 19 kDa protein‐interacting protein 3 (BNIP3) compared to eNOSfl/fl mice. Conclusion: Here we demonstrate for the first time that hepatocyte‐specific deletion of eNOS impairs hepatic mitochondrial function, reduces markers of autophagy/mitophagy, and exacerbates hepatic steatosis development. Further studies are necessary to determine the mechanisms by which deletion of eNOS regulates mitochondrial homeostasis. Support or Funding Information VA Merit Grant I01BX003271‐01 (R.S.R.) This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .