OBJECTIVETo observe the difference in fatty degree, glucose-lipid disorder and adipose-hormones between diet induced obesity (DIO) rats and diet induced obesity resistance (DIO-R) rats, and to explore the effect and acting mechanism of Chinese drugs for strengthening Pi (CD-SP) and those for both strengthening Pi and dissolving phlegm (CD-SPDP) in inhibiting obesity.

METHODSExcepting eight rats allocated in the blank control group, the other 54 rats were fed with high-lipid forage for 12 weeks to establish models of obesity. Finally, 30 DIO rats and 8 DIO-R rats (shown by their body weight) were obtained. The DIO rats were divided into three groups, which were given gastric perfusion, respectively, with normal saline (Group A), CD-SP (Group B), and CD-SPDP (Group C). Fourteen weeks later, the animals' body weight (BW), length (BL), blood levels of fasting insulin (FIn), fasting glucose (FBG), triglyceride (TG), cholesterol (TC), leptin (LP), neuropeptide Y (NPY), C-reactive protein (CRP), tumor necrosis factor-alpha(TNF-alpha), adiponectin (AN), and resistin (RS) were measured; insulin resistance index (IRI) was calculated, and the degree of obesity and lipid content in abdominal cavity of rats were estimated. Moreover, the levels of LP, CRP, TNF-alpha, AN and RS in homogenate of rats' adipose tissues (ATH) were determined.

RESULTSAfter 12 weeks of high-lipid diet, the BW of DIO rats was higher than that of normal or DIO-R rats. After a 14-week continuous high-lipid diet feeding, in DIO rats, BW, lipid coefficient (LC), and IRI were significantly increased (P<0.01); serum levels of TNF-alpha, LP and AN were lower, NPY was higher, while the ATH levels of LP and AN were lower and TNF-alpha was higher in DIO rats than in DIO-R rats (P<0.05 or P<0.01); blood levels of FBG and lipids in DIO rats showed an increasing trend but was statistically insignificant (P>0.05); no significant difference was found in serum levels of CRP and RS due to the overly high data dispersion. Comparisons of the 3 DIO groups showed that BW, body weight index (BWI), LC and IRI were significantly lowered after treatment (P<0.01) in Group C, while these indexes were not significantly different between Group A and B; the serum levels of TNF-alpha, LP, and AN increased, NPY decreased in Group B and C, ATH levels of LP and AN increased, and TNF-alpha decreased in the two groups; but NPY, LP, and AN in blood and ATH were higher in Group C than those in Group B (P<0.05 or P<0.01).

CONCLUSIONCD-SPDP could inhibit DIO and IR, showing that the effect is better than that of CD-SP, and its mechanism is related to promotion of LP and AN secretion and elevation of serum NPY.