The phytochemical epigallocatechin gallate prolongs the lifespan by improving lipid metabolism, reducing inflammation and oxidative stress in high-fat diet-fed obese rats
AGING CELL
Authors: Yuan, Hang; Li, Yuqiao; Ling, Fan; Guan, Yue; Zhang, Dandan; Zhu, Qiushuang; Liu, Jinxiao; Wu, Yuqing; Niu, Yucun
Abstract
We have recently reported that epigallocatechin gallate (EGCG) could extend lifespan in healthy rats. This study aimed to investigate the effects and mechanisms of a high dose of EGCG in extending the lifespan of obese rats. Ninety adult male Wistar rats were randomly divided into the control (NC), high-fat (HF) and EGCG groups. Serum glucose and lipids, inflammation and oxidative stress were dynamically determined from adulthood to death, and the transcriptome and proteome of the liver were also examined. The median lifespans of the NC, HF and EGCG groups were 693, 599 and 683 days, respectively, and EGCG delayed death by 84 days in obese rats. EGCG improved serum glucose and lipids and reduced inflammation and oxidative stress associated with aging in obese rats induced by a high-fat diet. EGCG also significantly decreased the levels of total free fatty acids (FFAs), SFAs and the n-6/n-3 ratio but significantly increased the n-3 FFAs related to longevity. The joint study of the transcriptome and proteome in liver found that EGCG exerted its effects mainly by regulating the suppression of hydrogen peroxide and oxygen species metabolism, suppression of oxidative stress, activation of fatty acid transport and oxidation and cholesterol metabolism. EGCG significantly increased the protein expression of FOXO1, Sirt1, CAT, FABP1, GSTA2, ACSL1 and CPT2 but significantly decreased NF-kappa B, ACC1 and FAS protein levels in the livers of rats. All the results indicate that EGCG extends lifespan by improving FFA metabolism and reducing the levels of inflammatory and oxidative stress in obese rats.
Meta analysis of candidate gene variants outside the LPA locus with Lp(a) plasma levels in 14,500 participants of six White European cohorts
ATHEROSCLEROSIS
Authors: Zabaneh, Delilah; Kumari, Meena; Sandhu, Manj; Wareham, Nick; Wainwright, Nick; Papamarkou, Theodore; Hopewell, Jemma; Clarke, Robert; Li, KaWah; Palmen, Jutta; Talmud, Philippa J.; Kronenberg, Florian; Lamina, Claudia; Summerer, Monika; Paulweber, Bernhard; Price, Jackie; Fowkes, Gerry; Stewart, Marlene; Drenos, Fotios; Shah, Sonia; Shah, Tina; Casas, Juan-Pablo; Kivimaki, Mika; Whittaker, John; Hingorani, Aroon D.; Humphries, Steve E.
Abstract
Background: Both genome-wide association studies and candidate gene studies have reported that the major determinant of plasma levels of the Lipoprotein (a) [Lp(a)] reside within the LPA locus on chromosome 6. We have used data from the HumanCVD BeadChip to explore the contribution of other candidate genes determining Lp(a) levels. Methods: 48,032 single nucleotide polymorphisms (SNPs) from the Illumina HumanCVD BeadChip were genotyped in 5059 participants of the Whitehall II study (WHII) of randomly ascertained healthy men and women. SNPs showing association with Lp(a) levels of p < 10(-4) outside the LPA locus were selected for replication in a total of an additional 9463 participants of five European based studies (EAS, EPIC-Norfolk, NPHSII, PROCARDIS, and SAPHIR). Results: In Whitehall II, apart from the LPA locus (where p values for several SNPs were < 10(-30)) there was significant association at four loci GALNT2, FABP1, PPARGC1A and TNFRSFF11A. However, a meta-analysis of the six studies did not confirm any of these findings. Conclusion: Results from this meta analysis of 14,522 participants revealed no candidate genes from the HumanCVD BeadChip outside the LPA locus to have an effect on Lp(a) levels. Further studies with genome-wide and denser SNP coverage are required to confirm or refute this finding. (C) 2011 Elsevier Ireland Ltd. All rights reserved.