Clinical Evidence

Effects of supplementation with Curcumin on serum adipokine concentrations: A randomized controlled trial
Nutrition. 2016, DOI: 10.1016/j.nut.2016.03.018
Metabolic syndrome (MetS), also known as syndrome X, has a worldwide prevalence ranging 10-84 %. It is a bunch of several cardiometabolic risk factors, including abdominal adiposity, hyperglycemia, hypertriglyceridemia, low high-density lipoprotein cholesterol (HDL-C) and hypertension. Insulin resistance and visceral adiposity are the key factors underlying MetS pathophysiology.

Owing to its proven and well established diversity of biological activities and several molecular targets, Curcumin has become an interesting phytochemical against a wide range of diseases, including MetS.

Several studies have demonstrated that Curcumin has the potential to modify almost all features of MetS, such as lowering plasma levels of total cholesterol, low-density lipoprotein cholesterol (LDL-C), triglyceride and glucose, and increasing those of HDL-C, and also possesses insulin-sensitizing, anti-obesity and anti-hypertensive properties. Curcumin has also been found to be targeting adiponectin and leptin, the most studied adipokines, whose levels are suggested to be altered in patients with MetS.

To evaluate changes in serum levels of adiponectin and leptin, and the ratio of these two adipokines, following Curcumin supplementation in patients with MetS.

Study Design:
  • This study was a post-hoc analysis performed on the samples obtained from previous investigation conducted by the same researchers’ group
  • The study was a 8-week, randomized, double-blind, placebo-controlled trial with a parallel group design
  • Subjects were randomized to receive either Curcumin (Curcumin C3 Complex®; n = 59) or matched placebo (n =58), once they met the inclusion criteria
  • Curcumin was administered at a daily dose of 1g (500 mg b.i.d.) and to improve the bioavailability of Curcumin, 5 mg piperine (BioPerine®) was also added
  • Placebo capsules contained the same amount of lactose plus 5 mg piperine
  • Blood samples were collected at baseline and at the end of the study, after overnight fasting
  • Commercial ELISA kits were used to estimate serum concentrations of leptin and adiponectin
  • Other parameters, such as weight, height, body-mass index (BMI) and systolic and diastolic blood pressures were measured according to standard procedures
Results and Discussion:
  • There was a significant elevation of serum adiponectin (p<0.001) and a significant reduction of serum leptin concentrations (p<0.001) in the Curcumin supplementation group compared with placebo group
  • Similarly, Curcumin supplementation resulted in significant decrease in serum leptin:adiponectin ratio in comparison to placebo group (p<0.001)
  • Impact of Curcumin supplementation on dependent variables, such as serum lipids and glucose concentrations, and baseline differences in BMI and serum levels of glucose and HbA1c, as potential confounders of treatment response, remained significant after adjustment for changes
  • Meta-analysis also suggested that Curcumin supplementation can increase adiponectin levels by 76.78% (p=0.0330) and reduce leptin by 26.49% (p=0.238)

Curcumin improved serum levels of adiponectin and leptin, and leptin:adiponectin ratio in patients with MetS, which has encouraged to conduct further detailed studies to ascertain the impact of Curcumin supplementation.