6-Gingerol Ameliorates Behavioral Changes and Atherosclerotic Lesions in ApoE-/- Mice Exposed to Chronic Mild Stress.

Abstract

Chronic mild stress (CMS) has been demonstrated to contribute to atherosclerosis. 6-gingerol (6-Gin), a phenolic component of ginger (Zingiber officinale), has been shown to exert numerous pharmacological properties, such as anti-inflammatory and cardioprotective effects. Here we investigated the roleof CMS inthe development of atherosclerosis in high-fat diet (HFD)-fed ApoE-/- mice and evaluated the potential therapeutic effects of 6-Gin. Mice were exposed to CMS for 20weeks, at week 5, they were fed with a high-fat diet (HFD), then received 6-Gin (20mg/kg/day, intragastrically) treatment. Antiatherosclerotic simvastatin (Sim) and antidepressant lorazepam (Lor) were used for positive drugs. The behavioral and atherosclerotic changes, plasma lipid profilesas well as inflammatory cytokine levels were measured. Our results showed that CMS-exposed mice exhibited reduced body weight gain,sucrose preference and locomotor activity, which are representative of some of the core symptoms of depression. Furthermore, CMS challenge aggravated atherosclerotic lesions,as indicated by increased plaque formation,elevationof plasma total cholesterol, triglyceride, low-density lipoprotein cholesterin, and proinflammatory cytokines including TNF-α, IL-1β, and IL-6. In addition, the expression levels of phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK), acetyl-CoA carboxylase (ACC), hHMG-CoA reductase(HMGCR), fatty acid synthase (FAS), sterol regulatory element binding protein (SREBP)-1 and SREBP-2 in theliver tissueswerealtered after CMS exposure. 6-Gin not onlyimproved thebehavioral changes, but alsoalleviated atherosclerotic lesions, andreversed the expression levels of lipid profilesand inflammatory cytokines in stressed mice. Moreover, the antiatherosclerotic effects of 6-Gin is mediated in part bythe AMPK signaling pathway, which is closelyassociated with cholesterol synthesis and lipid accumulation. Together, these results suggest that 6-Gin attenuates arteriosclerosis in ApoE-/- mice exposed to CMS and HFD, and it may be a potential therapeutic agent for the treatment of atherosclerosis.