Distal procto-colitis, natural cytotoxicity, and essential fatty acids

Area of Science:

• Immunology
• Gastroenterology
• Nutritional Science

Background:

• Ulcerative colitis is associated with altered natural cytotoxicity, involving natural killer (NK) and lymphokine-activated killer (LAK) cells.
• Essential fatty acids (EFA), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are known to inhibit natural cytotoxicity.
• The role of omega-3 EFA in modulating natural cytotoxicity and disease activity in distal procto-colitis requires further investigation.

Purpose of the Study:

• To evaluate the effect of omega-3 EFA supplementation on natural cytotoxicity and disease activity in patients with distal procto-colitis.
• To assess whether EPA and DHA can modulate NK and LAK cell activities in this patient population.
• To determine the potential of omega-3 EFA as a therapeutic strategy for inflammatory bowel disease.

Main Methods:

• A 6-month, double-blind, randomized pilot study comparing fish oil extract (EPA 3.2g, DHA 2.4g) with a sunflower oil placebo.
• Monthly assessments of clinical and sigmoidoscopic disease activity, along with histological evaluation of mucosal biopsies.
• Monitoring of circulating NK and LAK cell levels and activities using flow cytometry and chromium release assays.

Main Results:

• Supplementation with EFA led to clinical improvement compared to baseline.
• Significant reductions in sigmoidoscopic and histological scores were observed in the EFA group versus the placebo group.
• EFA supplementation significantly decreased circulating CD16+ and CD56+ cells and reduced NK cell cytotoxic activity.

Conclusions:

• Omega-3 fatty acids (EPA and DHA) can suppress natural cytotoxicity and reduce disease activity in patients with distal procto-colitis.
• These findings support a potential therapeutic role for omega-3 EFA in managing inflammatory bowel disease.
• Further research into omega-3 EFA as a management strategy for ulcerative colitis is warranted.