Liver-derived lipoproteins and inflammation: from pathophysiology to pharmacological targets in metabolic liver disease

Abstract

Low density lipoproteins (LDL) reduction remains the key goal for reducing the risk of atherosclerotic cardiovascular diseases (CVD) in people with high residual risk and metabolic complications including liver disease. Notwithstanding, epidemiological projections support a key role of liver-derived apolipoprotein B (ApoB) containing lipoproteins, namely very low density lipoproteins (VLDL) and their “remnants” (TG), undergoing the activity of lipases, in eliciting atherosclerotic inflammatory sequelae of a comparable order of magnitude to that of LDL. Disparate experimental evidence supports that triglycerides (TG), residual cholesterol content, or the large apolipoprotein set on the surface of these lipoproteins can elicit a number of plausible immune-inflammatory mechanisms that foster the vascular atherosclerotic process. Therapeutic options that convincingly lowered the plasma levels of liver-derived ApoB containing lipoproteins, either by reducing the hepatic synthesis or by improving the peripheral lipolysis of the lipid content, did not exert robust CVD risk reduction, and the effect on inflammation was questionable. Understanding the mechanisms linking liver-derived lipoproteins with chronic inflammation will provide pathophysiological insights for the identification of new therapeutic targets for people at high CVD risk and with metabolic complications. In this perspective, this topic is of immediate interest for the prevention of CVD in patients affected by non-alcoholic fatty liver disease (NAFLD) and, even more, for NAFLD patients with diabetes, insulin resistance, or other comorbidities (metabolic-associated fatty liver disease). This review resumes the principal physio-pathological insights regarding the metabolism of liver-derived lipoproteins and provides an update on the current pharmacological options that can be considered for improving CVD prevention in metabolic liver diseases.