Consumption of oils and anthocyanins may positively modulate PPAR-γ expression in chronic noncommunicable diseases: A systematic review.

Peroxisome proliferator-activated receptor-gamma (PPAR-γ) plays a central role in health and is an essential cardioprotective factor because of its effect on lipid and glucose metabolism, inflammation, and oxidative stress. We hypothesized that nutritional strategies positively regulate PPAR-γ expression in patients with noncommunicable diseases (NCDs). A systematic search was conducted using PubMed, Scientific Electronic Library Online (SciELO), and LILACS databases from May 2020 to January 2021. Eligibility criteria included placebo-controlled randomized clinical trials in adults with chronic diseases involving nutritional strategies, which performed PPAR-γ analysis (majority on mononuclear cells) before and after the intervention. The exclusion criteria included studies published more than 10 years ago, studies not published in English or Spanish, theses, reviews, and other study designs. The review was developed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Methodological quality was assessed based on 7 criteria obtained from the Cochrane Handbook. A total of 7 studies were included that reported the effects of different nutritional strategies (such as anthocyanins, fish oil, Berberis vulgaris juice, ketogenic diet, flaxseed oil, olive oil) on 346 patients with NCDs (such as type 2 diabetes, hypertension, obesity, and cancer) between 18 and 85 years of age. These results suggest that anthocyanins, flaxseed oil, and olive oil may function as putative PPAR-γ agonists.