Gastrodia elata Blume extract suppresses lipid accumulation in high-fat diet-fed rats: a biochemical and histopathological evaluation

Excessive consumption of high-fat diet (HFD) can easily cause obesity, hyperlipidemia, and fatty liver disease. Persistent elevation of blood lipid levels increases the risk of cardiovascular disease, with hyperlipidemia being a well-established risk factor. Gastrodia elata Blume (GEB) is a perennial orchid plant that is known to have beneficial effects on obesity and blood circulation. This study aimed to evaluate the effects of GEB extract on improving blood lipids in the hyperlipidemia model induced by HFD in rats. Wistar rats (five-week-old) were divided into 3 groups: Control (CON) group, HFD induced (HF) group, and GEB treated (GEB) group. The treatment of GEB extract reduced body weight gain, visceral fat, and epididymal fat weights. Serum total cholesterol (TC) levels were significantly lower in the GEB group than in the HF group. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were reduced in the GEB group than in the HF group. Histopathological analysis of the liver showed that the GEB group alleviated structural damage to the liver by reducing lipid accumulation in hepatocytes compared with the HF group in hematoxylin and eosin (H&E) and Oil red O staining. The adipocyte diameter was smaller in the GEB group than in the HF group, and the atherosclerosis index (AI) was significantly lower in the GEB group compared to the HF group. Furthermore, the mechanism underlying these effects was elucidated by demonstrating that GEB extract decreased the expression of sterol regulatory element-binding protein 1 (SREBP-1), a key regulator of cholesterol synthesis in the liver. These results indicate that GEB extract has the effect of improving blood and liver lipid levels.