title: Dietary supplementation with (-)-epigallocatechin-3-gallate reduces inflammatory response in adipose tissue of non-obese type 2 diabetic Goto-Kakizaki (GK) rats.
abstract: (-)-Epigallocatechin gallate (EGCG), a major catechin in green tea, is an antioxidant associated with the reduction of oxidative stress in vitro. However, the mechanisms underlying the effects of EGCG on adipose tissue-related metabolic disturbances in vivo are not understood. This study examined whether dietary supplementation of EGCG reduces the oxidative stress-associated inflammatory response in the mesenteric adipose tissue of non-obese type 2 diabetic Goto-Kakizaki (GK) rats. GK rats were fed a normal diet or diet containing 0.1, 0.2, or 0.5% EGCG (w/w) for 25 weeks. The mRNA levels of IL-1β were significantly reduced in GK rats given 0.1% EGCG (0.059 ± 0.008; means ± SEM in arbitrary unit) compared with those in GK rats given a control diet (0.135 ± 0.011), but not in those given 0.2% EGCG (0.123 ± 0.012) or 0.5% EGCG (0.112 ± 0.019). The mRNA and protein level of other genes for inflammatory responses such as IL-18, TNF-α, MCP-1, CD11s, CD18, and resistin were also significantly reduced in rats given 0.1% EGCG, but not in those given ≥ 0.2% EGCG. This suggests that supplementation with EGCG at relatively low concentrations (0.1%) in GK rats reduces expression of genes and proteins involved in inflammation in adipose tissue.
authors.affiliation: Laboratory of Nutritional Physiology, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka , 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Uchiyama
authors.forename: Takuji
authors.initials: T
authors.lastname: Suzuki
authors.forename: Kazuki
authors.initials: K
authors.lastname: Mochizuki
authors.forename: Toshinao
authors.initials: T
authors.lastname: Goda
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy* / Q000378:metabolism*; D019587:Dietary Supplements; D005786:Gene Expression Regulation / Q000187:drug effects; D007249:Inflammation / Q000178:diet therapy / Q000209:etiology / Q000235:genetics*; D008297:Male; D009765:Obesity / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar
chemical_list: D001786:Blood Glucose; D002392:Catechin; C045651:epigallocatechin gallate