35 research outputs found
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Multi-tissue profiling of oxylipins reveal a conserved up-regulation of epoxide:diol ratio that associates with white adipose tissue inflammation and liver steatosis in obesity
Data sharing statement:
The individual-level data used in this study cannot be publicly shared due to ethical approval. Data set will be made available upon request through contact with the corresponding author. For sharing of data within a scientific collaboration any proposal should be directed to the corresponding author. Data will only be shared in accordance with legal frameworks, and when the integrity of the individual study participant can be guaranteed. This will be decided by the corresponding author on a case-by-case basis.Background:
Obesity drives maladaptive changes in the white adipose tissue (WAT) which can progressively cause insulin resistance, type 2 diabetes mellitus (T2DM) and metabolic dysfunction-associated liver disease (MASLD). Obesity-mediated loss of WAT homeostasis can trigger liver steatosis through dysregulated lipid pathways such as those related to polyunsaturated fatty acid (PUFA)-derived oxylipins. However, the exact relationship between oxylipins and metabolic syndrome remains elusive and cross-tissue dynamics of oxylipins are ill-defined.
Methods:
We quantified PUFA-related oxylipin species in the omental WAT, liver biopsies and plasma of 88 patients undergoing bariatric surgery (female N = 79) and 9 patients (female N = 4) undergoing upper gastrointestinal surgery, using UPLC-MS/MS. We integrated oxylipin abundance with WAT phenotypes (adipogenesis, adipocyte hypertrophy, macrophage infiltration, type I and VI collagen remodelling) and the severity of MASLD (steatosis, inflammation, fibrosis) quantified in each biopsy. The integrative analysis was subjected to (i) adjustment for known risk factors and, (ii) control for potential drug-effects through UPLC-MS/MS analysis of metformin-treated fat explants ex vivo.
Findings:
We reveal a generalized down-regulation of cytochrome P450 (CYP)-derived diols during obesity conserved between the WAT and plasma. Notably, epoxide:diol ratio, indicative of soluble epoxide hydrolyse (sEH) activity, increases with WAT inflammation/fibrosis, hepatic steatosis and T2DM. Increased 12,13-EpOME:DiHOME in WAT and liver is a marker of worsening metabolic syndrome in patients with obesity.
Interpretation:
These findings suggest a dampened sEH activity and a possible role of fatty acid diols during metabolic syndrome in major metabolic organs such as WAT and liver. They also have implications in view of the clinical trials based on sEH inhibition for metabolic syndrome.Wellcome Trust (PS3431_WMIH); Duke-NUS (Intramural Goh Cardiovascular Research Award (Duke-NUS-GCR/2022/0020); National Medical Research Council (OFLCG22may-0011); National Institute of Environmental Health Sciences (Z01 ES025034); NIHR Imperial Biomedical Research Centre
Protection of Spanish Ibex (Capra pyrenaica) against Bluetongue Virus Serotypes 1 and 8 in a Subclinical Experimental Infection
Many wild ruminants such as Spanish ibex (Capra pyrenaica) are susceptible to Bluetongue virus (BTV) infection, which causes disease mainly in domestic sheep and cattle. Outbreaks involving either BTV serotypes 1 (BTV-1) and 8 (BTV-8) are currently challenging Europe. Inclusion of wildlife vaccination among BTV control measures should be considered in certain species. In the present study, four out of fifteen seronegative Spanish ibexes were immunized with a single dose of inactivated vaccine against BTV-1, four against BTV-8 and seven ibexes were non vaccinated controls. Seven ibexes (four vaccinated and three controls) were inoculated with each BTV serotype. Antibody and IFN-gamma responses were evaluated until 28 days after inoculation (dpi). The vaccinated ibexes showed significant (P<0.05) neutralizing antibody levels after vaccination compared to non vaccinated ibexes. The non vaccinated ibexes remained seronegative until challenge and showed neutralizing antibodies from 7 dpi. BTV RNA was detected in the blood of non vaccinated ibexes from 2 to the end of the study (28 dpi) and in target tissue samples obtained at necropsy (8 and 28 dpi). BTV-1 was successfully isolated on cell culture from blood and target tissues of non vaccinated ibexes. Clinical signs were unapparent and no gross lesions were found at necropsy. Our results show for the first time that Spanish ibex is susceptible and asymptomatic to BTV infection and also that a single dose of vaccine prevents viraemia against BTV-1 and BTV-8 replication
"Liver-on-a-Chip" cultures of primary hepatocytes and Kupffer cells for hepatitis B virus infection
Despite the exceptional infectivity of the hepatitis B virus (HBV) in vivo, where only three viral genomes can result in a chronicity of experimentally infected chimpanzees, most in vitro models require several hundreds to thousands of viral genomes per cell in order to initiate a transient infection. Additionally, static 2-D cultures of primary human hepatocytes (PHH) allow only short-term studies due to their rapid dedifferentiation. Here, we describe 3-D liver-on-a-chip cultures of PHH, either in monocultures or in cocultures with other nonparenchymal liver-resident cells. These offer a significant improvement to studying long-term HBV infections with physiological host cell responses. In addition to facilitating drug efficacy studies, toxicological analysis, and investigations into pathogenesis, these microfluidic culture systems enable the evaluation of curative therapies for HBV infection aimed at eliminating covalently closed, circular (ccc)DNA. This presented method describes the set-up of PHH monocultures and PHH/Kupffer cell co-cultures, their infection with purified HBV, and the analysis of host responses. This method is particularly applicable to the evaluation of long-term effects of HBV infection, treatment combinations, and pathogenesis
Cardiac glycosides cause cytotoxicity in human macrophages and ameliorate white adipose tissue homeostasis
Background and purpose: Cardiac glycosides (CGs) inhibit the Na+,K+‐ATPase and are widely prescribed medicines for chronic heart failure and cardiac arrhythmias. Recently, CGs have been described to induce inflammasome activation and pyroptosis in human macrophages, suggesting a cytotoxicity that remains to be elucidated in tissues. Experimental approach: To determine the cell type specificity of CG‐mediated cytotoxicity, we used human primary monocyte‐derived macrophages (hMDMs) and non‐adherent peripheral blood cells isolated from healthy donors. Omental white adipose tissue (WAT) and stromal vascular fraction (SVF)‐derived pre‐adipocytes and adipocytes were isolated from obese patients undergoing bariatric surgery. All these primary cells/tissues were treated with nanomolar concentrations of ouabain (50nM, 100nM and 500nM) to investigate its degree of cytotoxicity and mechanisms leading to cell death. In WAT, we further explored the consequences of ouabain‐mediated cytotoxicity by measuring insulin sensitivity, adipose tissue function and extracellular matrix (ECM) deposition ex vivo. Key results: The ouabain‐induced cell death is through pyroptosis and apoptosis, and more efficient in hMDMs compared to non‐adherent PBMC populations. This selective cytotoxicity is dependent on K+ flux, as ouabain causes an intracellular depletion of K+, while inducing accumulation of Na+ and Ca2+ levels. Consistently, the cell‐death caused by these ion imbalances can be rescued by addition of potassium chloride in hMDMs. Remarkably, when WAT explants from obese patients are cultured with nanomolar concentrations of ouabain, this causes depletion of macrophages, down‐regulation of type VI collagen levels, and amelioration of insulin sensitivity ex vivo. Conclusions and implications: These results suggest that the usage of nanomolar concentration of CGs can be an attractive therapeutic avenue in metabolic syndrome characterised by pathogenic infiltration and activation of macrophages
Combined DOCK8 and CLEC7A mutations causing immunodeficiency in 3 brothers with diarrhea, eczema, and infections
Pre-injury neuro-psychiatric medication use, alone or in combination with cardiac medications, may affect outcomes in trauma patients
Background: Recent review of older (≥45-years-old) patients admitted to our trauma center showed that more than one-third were using neuro-psychiatric medications (NPMs) prior to their injury-related admission. Previously published data suggests that use of NPMs may increase patients′ risk and severity of injury. We sought to examine the impact of pre-injury NPM use on older trauma patients′ morbidity and mortality. Materials and Methods: Retrospective record review included medication regimen characteristics and NPM use (antidepressants-AD, antipsychotics-AP, anxiolytics-AA). Hospital morbidity, mortality, and 90-day survival were examined. Comparisons included regimens involving NPMs, further focusing on their interactions with various cardiac medications (beta blocker - BB; angiotensin-converting enzyme inhibitor/angiotensin receptor blocker - ACE/ARB; calcium channel blocker - CCB). Results: 712 patient records were reviewed (399 males, mean age 63.5 years, median ISS 8). 245 patients were taking at least 1 NPM: AD (158), AP (35), or AA (108) before injury. There was no effect of NPM monotherapy on hospital mortality. Patients taking ≥3 NPMs had significantly lower 90-day survival compared to patients taking ≤2 NPMs (81% for 3 or more NPMs, 95% for no NPMs, and 89% 1-2 NPMs, P < 0.01). Several AD-cardiac medication (CM) combinations were associated with increased mortality compared to monotherapy with either agent (BB-AD 14.7% mortality versus 7.0% for AD monotherapy or 4.8% BB monotherapy, P < 0.05). Combinations of ACE/ARB-AA were associated with increased mortality compared to ACE/ARB monotherapy (11.5% vs 4.9, P = 0.04). Finally, ACE/ARB-AD co-administration had higher mortality than ACE/ARB monotherapy (13.5% vs 4.9%, P = 0.01). Conclusions: Large proportion of older trauma patients was using pre-injury NPMs. Several regimens involving NPMs and CMs were associated with increased in-hospital mortality. Additionally, use of ≥3 NPMs was associated with lower 90-day survival