A prospective, randomized, double – blind, placebo – controlled trial of polyphenols on the outcomes of inflammatory factors and oxidative stress in patients with type 2 diabetes mellitus
Background: Type 2 diabetes mellitus (T2DM) is commonly associated with hyperglycemia, dyslipidemia, oxidative stress and inflammation which are well known cardiovascular risk factors. Pomegranate peel polyphenols have a proven hypolipemic, antioxidant and
anti-inflammatory activity. However, there is a lack of clinical studies that would confirm its antioxidant and anti-inflammatory effects
in diabetic patients. The potential of pomegranate peel extract (PoPEx) to counteract inflammation and oxidative stress in T2DM patients was investigated. For this purpose, a randomized, double-blind placebo-controlled study involving adult T2DM patients treated
with PoPEx or placebo for eight-weeks was conducted. Methods: Patients were randomly divided into two groups: the first group (n
= 30) received capsules containing PoPEx 250 mg twice daily, while the placebo group (n = 30) received placebo capsules twice daily.
Plasma concentration of inflammatory factors (interleukin 6 (IL-6), tumor necrosis factor α (TNF-α) and high sensitivity C reactive
protein (hsCRP)), oxidative stress biomarkers (thiobarbituric acid reactive substances (TBARS), nitrites (NO2
−), superoxide anion radical (O2
−), hydrogen peroxide (H2O2), total antioxidant capacity (TAC)), homocysteine and lipid profile were analyzed. Results: The
PoPEx treatment showed a significant reduction of inflammatory factors (IL-6, TNF-α, hsCRP), oxidative stress biomarkers (TBARS,
NO2
−, O2
−) and homocysteine, while the TAC was increased. Moreover, a significant improvement in lipid profile was observed in
the PoPEx group. Additional analysis showed a significant inverse correlation between the decrements of all measured inflammatory
markers and TAC in the PoPEx group. Conclusions: The study demonstrated that eight-week-long PoPEx administration had favorable
effects on inflammatory status and oxidative stress biomarkers in diabetic patients.