The aim of the study was to examine the mechanism of action of Lidan Granule (LDG) for the prevention of gallstones using a guinea pig model. One hundred guinea pigs were divided into five groups randomly: control (standard diet and saline), model [lithogenic diet (LD) and saline], LDG-H (LD and 2 g/kg of LDG), LDG-L (LD and 1 g/kg of LDG), and ursodeoxycholic acid (UDCA) (LD and UDCA) as the positive control. At 6 weeks, the rate of gallstone formation and weight of the adrenal gland were recorded and serum levels of inflammatory cytokines were measured. Levels of corticotrophin-releasing hormone (CRH) in the hypothalamus, adrenocorticotropic hormone (ACTH) in the hypophysis, and serum cortisol were determined. Bile components were tested with colorimetry. At 6 weeks, the rate of gallstone formation was significantly decreased in the LDG-H (14.29%) and LDG-L (21.43%) groups compared to the model group (81.25%; P<0.01). LDG treatment decreased the serum levels of interleukin (IL)-1, IL-6, and tumor necrosis factor-α (P<0.01). LDG decreased bile cholesterol and increased bile acid and phospholipid levels in the bile (P<0.01). LDG treatment recovered the function of the hypothalamic-pituitary-adrenal (HPA) axis by increasing the expression of CRH (P<0.01) and ACTH (P<0.05). LDG made the bile less lithogenic, improved the function of the HPA axis, and regulated the expression of inflammatory cytokines for the prevention of cholelithiasis.
Keywords: Lidan Granule; hypothalamic-pituitary-adrenal axis; inflammation; pigment gallstones.