The Effect of Phytochemical Extracts on Cytokine Gene Expression

Abstract

Background: In the last century, nutritional supplements have shown a wide spectrum of biochemical effects, most notably about immunomodulation and countering inflammation. Objective: This study investigates the impact of phytochemical compounds that are present in different quantities of pomegranate, grape seeds and garlic extracts on the expression of inflammatory (IL1β and IL6) and anti-inflammatory (IL10) genes, the effects of polymorphisms in these genes on this response. Methods: Human peripheral blood leukocyte cultures were treated with pomegranate (1.2% or 2.4%), garlic (0.5% or 1.2%), or grape seed (1.2% or 2.4%) extracts. Gene expression was assessed with real-time polymerase chain reaction (PCR). Polymorphisms of the cytokine genes were analyzed using allele-specific PCR. Results: Pomegranate extract (2.4%) reduced the transcription of IL1β by 16-fold in comparison to control. The expression of IL6 relative to the control after the addition of grape seed extract (1.2%) was reduced by 100-fold. The grape seeds extract (1.2%) showed the effect of increasing transcription for IL10 compared to the control. The level of IL1β transcription in culture with garlic extract depends on the genotype of the cell for -31T>C polymorphism (r = 0.67 p = 0.03). There is correlation between polymorphism -174G>C and level gene expression IL6 (r=-0.66, p = 0.04) after adding grape seeds extract. Conclusion: The phytochemical compounds in pomegranate extracts and grape seed extracts play the role of anti-inflammatory by decreasing the gene expression of IL1β, IL6 and increasing the transcription of IL10.