Very Low-Calorie Ketogenic Diet (VLCKD) and molecular liver cells modification mediated by Small Extracellular Vesicles (sEVs)

The very low-calorie ketogenic diet (VLCKD) has emerged as an effective weight loss strategy for obese patients. It significantly reduces visceral adipose tissue (VAT), which is cardinal for mitigating metabolic complications associated with obesity. By promoting rapid weight loss, VLCKD helps to decrease insulin resistance and alleviate inflammation. Chronic liver inflammation can progress to severe conditions like non-alcoholic steatohepatitis and fibrosis, potentially resulting in liver failure and hepatocellular carcinoma. Transient elastography (FibroScan) is a known technique for assessing hepatic steatosis, with FIB E levels below 8kPa indicating low fibrosis risk (LR), while levels above 8kPa suggest a higher risk of chronic liver disease (IHR). Prevention of fibrosis includes lifestyle changes such as a healthy diet and increased physical activity. Traditional low-calorie diets often fail to achieve significant weight loss; hence, the very low-calorie ketogenic diet (VLCKD) is proposed as an effective strategy to decrease VAT and insulin resistance. Recent studies indicate extracellular vesicles (EVs), particularly small EVs (sEVs), play a crucial role in liver fibrosis by activating hepatic stellate cells. Our group identified that sEVs, to be involved in liver degeneration binded to the fibrosis. The aim of this study is to investigate the role of sEVs in 60 obese adults classified as LR and IHR based on FIB E score, enrolled in an 8-week VLCKD weight loss program. Remarkably, the cellular reactivity to sEVs derived from these patients in the early production and modulation of certain fibrosis markers, such as MMPs, and stress fibres Vimentin, and α-Actin was studied. We used RNA sequencing technology to understand the molecular changes of HEPA-RG after stimulation with patient-derived EXOs before (T0) and after (T1) treatment with a VLCKD, using samples from both IHR and LR patients