Chia (Salvia hispanica L.) enhances HSP, PGC-1α expressions and improves glucose tolerance in diet-induced obese rats

Objective: The aim of this study was to investigate the effects of chia seed and chia oil on heat shock protein (HSP) and related parameters in diet-induced obese rats. Methods: Animals were divided in six groups: control, high-fat and high-fructose diet (HFF), and HFF with chia seed or chia oil in short (6-wk) and long (12-wk) treatments. Plasma indicators of glucose tolerance and liver damage, skeletal muscle expression of antioxidant enzymes, and proteins controlling oxidative energy metabolism were determined. The limit of significance was set at P < 0.05. Results: The HFF diet induced glucose intolerance, insulin resistance, oxidative stress, and altered parameters related to obesity complications. The consumption of chia seed or chia oil did not reduce body weight gain or abdominal fat accumulation. However, chia seed and chia oil in both treatments improved glucose and insulin tolerance. Chia oil in both treatments induced expression of HSP70 and HSP25 in skeletal muscle. Short treatment with chia seed increased expression of HSP70, but not HSP25. Chia oil in both treatments restored superoxide dismutase and glutathione peroxidase expression. Extended treatment with chia seed and short treatment with chia oil restored peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1 alpha) expression. Conclusion: Chia oil restored the antioxidant system and induced the expression of a higher number of proteins than chia seed. The present study demonstrated new properties and molecular mechanisms associated with the beneficial effects of chia seed and chia oil consumption in diet-induced obese rats. (C) 2015 Elsevier Inc. All rights reserved.