Curcumin and other dietary polyphenols: potential mechanisms of metabolic actions and therapy for diabetes and obesity

Abstract

Recent controversy regarding the therapeutic potential of curcumin indicates the challenges to research in this field. Here, we highlight the investigations of curcumin and other plant-derived polyphenols that demonstrate their application to metabolic diseases, in particular, obesity and diabetes. Thus, a number of preclinical and clinical investigations have shown the beneficial effect of curcumin (and other dietary polyphenols) in attenuating body weight gain, improving insulin sensitivity, and preventing diabetes development in rodent models and prediabetic subjects. Other intervention studies with dietary polyphenols have also found improvements in insulin resistance. Recent studies suggest that the metabolic effects of curcumin/polyphenols are linked to changes in the gut microbiota. Thus, research into curcumin continues to provide novel insights into metabolic regulation that may ultimately translate into effective therapy.

Curcumin and dietary polyphenol research: beyond drug discovery

“…This, along with other chemistry features of curcumin, has generated enormous difficulties in the detailed dissection of mechanistic pathways underlying its bio-medical functions. Indeed, these features have been causing some confusion among drug developers and have been heavily debated recently [82][83][84][85] . However, investigations presented by numerous investigators, including our team, suggest that the implications of dietary polyphenol research are beyond the scope of drug development.…”

Bioactive food and exercise in chronic kidney disease: Targeting the mitochondria

“…In animal models of experimental CKD, curcumin protects against mitochondrial dysfunction and decreases oxygen consumption by reducing ROS production . However, it has been reported that curcumin is somewhat difficult to study since it is rapidly degraded in vivo and have very low bioavailability . Curcumin, as well as other polyphenols, activates Nrf‐2 and stimulates an antioxidant response .…”

“…63,64 However, it has been reported that curcumin is somewhat difficult to study since it is rapidly degraded in vivo and have very low bioavailability. 65 Curcumin, as well as other polyphenols, activates Nrf-2 and stimulates an antioxidant response. 66 Even though knowledge of the exact molecular activity of this polyphenol is limited, it has been thoroughly studied in relation to cancer.…”

The effects of curcumin supplementation on body mass index, body weight, and waist circumference in patients with nonalcoholic fatty liver disease: A systematic review and dose–response meta‐analysis of randomized controlled trials

“…Chronic systemic inflammation has been proposed as the main factor in the development and progression of several noncommunicable diseases, including metabolic syndrome, cardiovascular diseases, obesity, and cancer (Namazi, Larijani, & Azadbakht, ). Several mechanisms have been proposed for effects of anti‐inflammatory diets and their ingredients such as curcumin on obesity and WC including inhibition of the lipogenesis and inflammation (reducing proinflammatory cytokines), suppressing angiogenesis in adipose tissue, downregulating preadipocyte differentiation, increasing lipolysis, brown fat tissue, adipocyte energy metabolism and apoptosis, serum levels of nesfatin, and probiotics‐like effects (Jin, Song, Weng, & Fantus, ; Navekar et al, ; Zhang, Fu, Gao, & Liu, ). The effects of nesfatin include appetite loss, reducing body fat, anti‐inflammation, antihyperglycemic, metabolic, and neuroendocrine regulation (Dong et al, ; Shen, Han, Cai, & Wang, ).…”

“…Chronic systemic inflammation has been proposed as the main factor in the development and progression of several noncommunicable diseases, including metabolic syndrome, cardiovascular diseases, obesity, and cancer (Namazi, Larijani, & Azadbakht, 2018). (Jin, Song, Weng, & Fantus, 2018;Navekar et al, 2017;Zhang, Fu, Gao, & Liu, 2013). The effects of nesfatin include appetite loss, reducing body fat, anti-inflammation, antihyperglycemic, metabolic, and neuroendocrine regulation (Dong et al, 2013;Shen, Han, Cai, & Wang, 2015).…”