Preventive effect of fat accumulation by Curcuma longa L. (MingDao No. 1 turmeric) rhizomes in 3T3-L1 preadipocytes and high fat diet-induced obese BALB/c mice

• Main Authors: Pei-Hsuan Chiu, 邱珮瑄
• Other Authors: 蔣慎思
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/03820444514096878872

碩士 === 國立中興大學 === 食品暨應用生物科技學系所 === 102 === Obesity is caused by an imbalance between energy intake and expenditure, which increases the size of adipocytes by conversion of extra energy to lipids and accumulates in adipose tissues. Obesity is associated with the variety of diseases such as diabetes, nonalcoholic fatty liver, dyslipidemia, hypertension and cardiovascular diseases. Preadipocyte differentiation is a major process to determine the number of mature adipocytes in the development of obesity. The aim of this study was to investigate the anti-adipogenesis effects of essential oil from Curcuma longa L. rhizomes (MingDao No. 1 turmeric essential oil, MDTE) in 3T3-L1 preadipocytes. 3T3-L1 preadipocytes were exposed to the adipogenic medium followed by treated with curcumin (tCur), ar-turmerone (aTur) and MDTE during differentiation process. After 9 days treatment, the levels of lipid accumulation were determined by Oil Red O staining. The glycerol release and heparin-releasable LPL activity were used to evaluate the lipolysis and lipogenesis functions. RT-PCR (real time-polymerase chain reaction) analysis was used to estimate the gene expression of adipocytes differentiation and lipid metabolism. The results showed that 20 μM tCur, 1 μM aTur and 20 ~ 50 μg/mL MDTE treatments could significantly inhibit the lipid accumulation and MDTE increased the glycerol release by up-regulating lipolysis activity. The mRNA expressions of C/EBPδ, C/EBPβ, C/EBPα, PPARγ and SREBP-1c were reduced during preadipocytes differentiation, as well as LPL, CD36, GLUT4, aP2, ACC1 and FAS expressions were down-regulated in triglyceride synthesis pathway and resistin secretion was decreased by adipocytes. The preventive effect of fat accumulation by Curcuma longa L. (MingDao No. 1 turmeric powder, MDTP) was evaluated in vivo model. Eleven-week-old male BALB/c mice were fed normal diet as control group (n=8) and high-fat diet to induce obesity (n=32) for twelve weeks. Subsequently, obesity BALB/c mice were randomly divided into four groups (n=8), including high-fat diet (HFD), HFD plus 1.25% MDTP (LCL), HFD plus 2.5% MDTP (MCL) and HFD plus 5% MDTP (HCL) groups. All samples were fed for twelve weeks. Body weights and food intake of BALB/c mice were weekly recorded. After sacrifice, serum biochemical parameters and histopathological analysis were assayed. The results showed that administration of LCL, MCL and HCL significantly reduced body weights (13.27%, 12.42% and 9.91%), body fat ratio (2.05%, 2.03% and 2.09%), serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and triglyceride levels compared to the HFD group (p<0.05). Histopathological analysis revealed that the score of fatty liver in HFD group (5.00.0) was significantly higher than that of LCL, MCL and HCL groups (3.31.0, 2.90.6 and 1.60.7, respectively) (p<0.05). Real-time PCR analysis indicated that LCL, MCL and HCL increased the mRNA expression of PPARα and CPT-1 compared to the HFD group (p<0.05). In conclusion, tCur, aTur and MDTE can inhibit the differentiation and lipid accumulation in 3T3-L1 preadipocytes. Furthermore, oral administration of MDTP is beneficial for the suppression of fat accumulation in obese BALB/c mice.