Chen Min-li

Involvement of peroxisome proliferator-activated receptors in cardiac and vascular remodeling in a novel minipig model of insulin resistance and atherosclerosis induced by consumption of a high-fat/cholesterol diet

BackgroundA long-term high-fat/cholesterol (HFC) diet leads to insulin resistance (IR), which is associated with inflammation, atherosclerosis (AS), cardiac sympathovagal imbalance, and cardiac dysfunction. Peroxisome proliferator-activated receptors (PPARs) and nuclear factor ĸB (NF-κB) are involved in the development of IR-AS. Thus, we elucidated the pathological molecular mechanism of IR-AS by feeding an HFC diet to Tibetan minipigs to induce IR and AS.MethodsMale Tibetan minipigs were fed either a normal diet or an HFC diet for 24 weeks. Thereafter, the minipigs were tested for physiological and biochemical blood indices, blood pressure, cardiac function, glucose tolerance, heart rate variability (HRV), and PPAR-associated gene and protein expression levels.ResultsHFC-fed minipigs exhibited IR through increased body weight, fasting blood glucose levels, plasma cholesterol and its composition, and insulin and free fatty acid (FFA) levels; decreased insulin sensitivity; impaired glucose tolerance; and hypertension. Increased C-reactive protein (CRP) levels, cardiac dysfunction, depressed HRV, and the up-regulation of PPAR expression in the abdominal aorta concomitant with down-regulation in the heart tissue were observed in HFC-fed minipigs. Furthermore, the levels of NF-κBp65, IL-1β, TNF-α, MCP-1, VCAM-1, ICAM-1, MMP-9, and CRP proteins were also significantly increased.ConclusionsThese data suggest that HFC-fed Tibetan minipigs develop IR and AS and that PPARs are involved in cardiovascular remodeling and impaired function.

Monitoring inbreeding of WHBE rabbits using microsatellites

Microsatellite polymorphisms were analyzed in F5, F6 and F7 WHBE rabbits (Oryctolagus cuniculus) to monitor inbreeding. Out of 21 microsatellite loci, 11 were successfully amplified and showed polymorphic. For the F5 WHBE rabbits, the number of alleles per locus (Na) ranged from 3 to 9 and the mean effective number of alleles (Ne) was 1.81. The mean value of observed heterozygosity (Ho) and polymorphism information content (PIC) of the 11 polymorphic loci were 0.381 and 0.524, respectively. The power of cumulative discrimination (CDP) was 1.0. The value of cumulative exclusion probability of the 11 polymorphic loci in the absence (CPE-1) or in the presence of genetic information on the first parent (CPE-2) was 0.926 and 0.993, respectively. For the F6 WHBE rabbits, Na per locus ranged from 3 to 8 and the mean value of Ne was 1.68. The mean value of Ho, PIC, CDP, CPE-1, CPE-2 of the 11 polymorphic loci were 0.356, 0.548, 1.0, 0.931, 0.994 respectively. For the F7 WHBE rabbits, Na per locus ranged from 2 to 6 and the mean value of Ne was 1.51. The mean value of Ho, PIC, CDP, CPE-1, CPE-2 of the 11 polymorphic loci were 0.287, 0.498, 1.0, 0.891, 0.986 respectively. The average number of effective alleles and the average observed heterozygosity were decreasing continuously in F5, F6 and F7, suggesting that the purity of WHBE rabbits was increasing continuously.