Nonalcoholic Fatty Liver Disease Among Individuals with HIV Mono-infection: A Growing Concern?

Chronic binge alcohol mediated hepatic metabolic adaptations in SIV-infected female rhesus macaques

AIMS

As the interactions of alcohol and HIV/SIV infection and their impact on liver metabolic homeostasis remain to be fully elucidated, this study aimed to determine alcohol-mediated hepatic adaptations of metabolic pathways in SIV/ART-treated female rhesus macaques fed a nutritionally balanced diet.

METHODS

Macaques were administered chronic binge alcohol (CBA; 13-14 g ethanol/kg/week for 14.5 months; n = 7) or vehicle (VEH; n = 8) for 14.5 months. Livers were excised following an overnight fast. Gene and protein expression, enzymatic activity, and lipid content were determined using frozen tissue and histological staining was performed using paraffin-embedded tissue.

RESULTS

CBA/SIV macaques showed increased hepatic protein expression of electron transport Complex III and increased gene expression of glycolytic (phosphofructokinase and aldolase) and gluconeogenic (pyruvate carboxylase) enzymes and of genes involved in lipid turnover homeostasis (perilipin 1, peroxisome proliferator-activated receptor gamma, carbohydrate responsive binding protein, and acetyl-CoA carboxylase B) as compared to that of livers from the VEH/SIV group. Plasma triglyceride concentration had a significant positive association with liver triglyceride content in the CBA/SIV group.

CONCLUSIONS

These results reflect CBA-associated alterations in expression of proteins and genes involved in glucose and lipid metabolism homeostasis without significant evidence of steatosis or dysglycemia. Whether these changes predispose to greater liver pathology upon consumption of a high fat/high sugar diet that is more aligned with dietary intake of PWH and/or exposure to additional environmental factors warrants further investigation.

Innovative Therapeutic Approaches in Non-Alcoholic Fatty Liver Disease: When Knowing Your Patient Is Key

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of disorders ranging from simple steatosis to non-alcoholic steatohepatitis (NASH). Hepatic steatosis may result from the dysfunction of multiple pathways and thus multiple molecular triggers involved in the disease have been described. The development of NASH entails the activation of inflammatory and fibrotic processes. Furthermore, NAFLD is also strongly associated with several extra-hepatic comorbidities, i.e., metabolic syndrome, type 2 diabetes mellitus, obesity, hypertension, cardiovascular disease and chronic kidney disease. Due to the heterogeneity of NAFLD presentations and the multifactorial etiology of the disease, clinical trials for NAFLD treatment are testing a wide range of interventions and drugs, with little success. Here, we propose a narrative review of the different phenotypic characteristics of NAFLD patients, whose disease may be triggered by different agents and driven along different pathophysiological pathways. Thus, correct phenotyping of NAFLD patients and personalized treatment is an innovative therapeutic approach that may lead to better therapeutic outcomes.

Second hits exacerbate alcohol-related organ damage: an update

Chronic and excessive alcohol abuse cause direct and indirect detrimental effects on a wide range of body organs and systems and accounts for ~4% of deaths worldwide. Many factors influence the harmful effects of alcohol. This concise review presents newer insights into the role of select second hits in influencing the progression of alcohol-induced organ damage by synergistically acting to generate a more dramatic downstream biological defect. This review specifically addresses on how a lifestyle factor of high fat intake exacerbates alcoholic liver injury and its progression. This review also provides the mechanistic insights into how increasing matrix stiffness during liver injury promotes alcohol-induced fibrogenesis. It also discusses how hepatotropic viral (HCV, HBV) infections as well as HIV (which is traditionally not known to be hepatotropic), are potentiated by alcohol exposure to promote hepatotoxicity and fibrosis progression. Finally, this review highlights the impact of reactive aldehydes generated during alcohol and cigarette smoke coexposure impair innate antimicrobial defense and increased susceptibility to infections. This review was inspired by the symposium held at the 17th Congress of the European Society for Biomedical research on Alcoholism in Lille, France entitled 'Second hits in alcohol-related organ damage'.