The anti-inflammatory and antioxidant effects of acute consumption of pigmented rice in humans

Food Funct. 2019 Dec 11;10(12):8230-8239. doi: 10.1039/c9fo02455g.

Abstract

The pathogenesis of lifestyle diseases has been significantly correlated to high levels of oxidative stress and pro-inflammation. The antioxidant and anti-inflammatory properties of polyphenols in coloured rice varieties could have potential to neutralize oxidative stress and modulate inflammatory responses. A cross-over design, randomised, dietary intervention human clinical trial was conducted on a pre-screened healthy population (n = 24) investigating the antioxidant and anti-inflammatory potential of pigmented rice (purple, red and brown) varieties. Post baseline blood samples collection volunteers consumed a serve of cooked pigmented rice. Blood samples were collected at 30-minutes, 1, 2 and 4-hours post rice consumption. A one-week wash-out period between each supplementation bout (rice variety) was conducted. Blood and biochemical parameters were analysed on baseline blood samples. Antioxidant activity, malondialdehyde (MDA) and a pro-inflammatory cytokine panel were analysed on the blood samples collected. Post purple rice consumption, antioxidant activity increased (p < 0.0001) by 70.5% and maintained elevated for all time points. The red rice variety Yunlu29, significantly (p < 0.005) reduced MDA levels by 9.2% at the 30-minute time point. Purple rice demonstrated a significant (p < 0.05) decrease by 4.0% at the 30-minute time point only. Purple rice significantly decreased TNF-α levels at the 1-hour (p < 0.05) and 4-hour (p < 0.005) time points by 21.9% and 25.4% respectively. IL-6 concentrations were significantly reduced at 1 and 2-hour post Purple (p < 0.05; 11.7%) and Yunlu29 (red) (p < 0.01; 14.1%) consumption respectively. The brown rice variety did not affect any parameters tested. The outcomes of this study, highlight that polyphenols found in pigmented rice may play a key role in targeting specific oxidative stress and inflammatory therapeutic pathways. Pigmented rice varieties may serve as a potential functional food in reducing risk factors associated with lifestyle diseases.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Anti-Inflammatory Agents / metabolism*
  • Antioxidants / metabolism*
  • Cooking
  • Cytokines / blood
  • Female
  • Functional Food / analysis
  • Humans
  • Interleukin-6 / blood
  • Male
  • Malondialdehyde / blood
  • Oryza / chemistry
  • Oryza / metabolism*
  • Oxidative Stress
  • Plant Extracts / metabolism*
  • Young Adult

Substances

  • Anti-Inflammatory Agents
  • Antioxidants
  • Cytokines
  • Interleukin-6
  • Plant Extracts
  • Malondialdehyde