Jueming prescription and its ingredients, semen cassiae and Rhizoma Curcumae Longae, stimulate lipolysis and enhance the phosphorylation of hormone-sensitive lipase in cultured rat white adipose tissue

The present study aimed to investigate the effect of jueming prescription (JMP) and its ingredients, semen cassiae (SC) and Rhizoma Curcumae Longae (RCL), on lipolysis, and to examine their effect on the phosphorylation of hormone-sensitive lipase (HSL) in cultured rat white adipose tissue (WAT). Retroperitoneal WAT was aseptically excised from adult male Sprague-Dawley rats, minced into uniform sections and subjected to ex vivo culture for 24 h. The tissue sections were then distributed into a 24-well culture plate and treated with normal saline (vehicle), isoproterenol (ISO), JMP, SC and RCL. Non-esterified fatty acid (NEFA) and glycerol release from the intact WAT explants were determined as a measurement of lipolysis, which were measured using NEFA and glycerol assay kits. The phosphorylation of HSL at Ser563 (P-HSL S563) and 660 residues (P-HSL S660) were determined using western blot analysis. The size of the adipocytes was visualized using hematoxylin and eosin (H&E) staining. It was found that JMP-, SC- and RCL-stimulated lipolysis was responsible for increasing the release of NEFAs and glycerol from the intact WAT in vitro. In addition, JMP, SC and RCL increased the levels of P-HSL Ser563: JMP water (JW) extract, 3.52-fold; JMP ethanol (JE) extract, 3.38-fold; SC water (SW) extract, 4.60-fold; SC ethanol (SE) extract, 4.20-fold; RCL water (RW) extract, 6.98-fold; RCL ethanol (RE) extract, 6.60-fold. JMP, SC and RCL also increased the levels of P-HSL Ser660: JW extract, 3.16-fold; JE extract, 2.92-fold; SW extract, 4.57-fold; SE extract, 4.13-fold; RW extract, 5.41-fold; RE 4.96-fold) in the WAT. The RW extract had the most marked effect. The HE staining revealed that JMP, SC and RCL reduced the size of adipocytes in the WAT. In conclusion, JMP and its ingredients, SC and RC, stimulated lipolysis and reduced the size of adipocytes, possibly via the phosphorylation of HSL in cultured rat WAT.