Cannabidiol and sphingolipid metabolism: an unexplored link offering a novel therapeutic approach against high-fat diet-induced hepatic insulin resistance

Abstract

Despite extensive research on insulin resistance, which is associated with type 2 diabetes and obesity, there remains a lack of effective and safe methods to treat it. Thus, we hypothesized that cannabidiol (CBD), which influences lipid accumulation and inflammatory response, may interact with sphingolipid metabolism and insulin signaling. To investigate the effects of CBD, male Wistar rats were fed a standard rodent chow or high-fat diet for 7 weeks to induce IR and were treated with CBD or its vehicle administered intraperitoneally for the last 2 weeks of the experiment. High-Performance Liquid Chromatography (HPLC) was used to assess sphingolipid concentration in the liver, while multiplex assay and western blotting were used to investigate the level or expression of proteins in the insulin signaling pathway and sphingolipid metabolism. Our results revealed that CBD prevented ceramide deposition in the liver of high-fat-fed rats through inhibition of the ceramide de novo synthesis pathway. Moreover, the accumulation of sphingosine-1-phosphate was notably increased with impaired catabolic pathway. Observed changes in the sphingolipid pathway coincided with improved insulin signaling after CBD treatment in animals fed a high-fat diet. Considering the presented evidence, CBD exerted a beneficial effect on insulin sensitivity in a state of lipid overload through the modification of sphingolipid deposition. Our study reveals the importance of broadening IR treatment methods, especially with natural substances that lack serious side effects such as CBD.