(P27-007-24) Atlantic Mackerel Is Protective in DSS-Induced Colitis Rat Models

Objectives: Fish consumption is below recommendation in American diets.  Atlantic mackerel (AM) is rich in nutrients and low in cost.  The purpose of this study was to determine the effect of AM on DSS-induced colon inflammation and colitis in rats.

Methods: Three-week-old male Sprague-Dawley rats were ordered from Charles River Laboratories.  After 1 week acclimation, rats were randomly divided into 6 groups (6 rats per group) to receive the control AIN93G diet, control with 1% or 5% AM for 4 weeks, followed by continued tap water or 3% DSS solution for 1 week.  Animals recovered in regular tap water for an additional 1 week prior to necropsy.  Animals were single-housed and fed ad libitum.  Food intake was monitored weekly.  Blood, liver, and colonic lamina propria (LP) tissues were collected.  Colon samples were also fixed in 10% formalin for histology studies.  Total proteins and total RNAs were extracted from LP tissues for immunoblotting and real-time PCR analysis, respectively.

Results: AM supplementation did not cause any changes in food intake, compared to the control groups. There were also no changes in body weight losses in groups with or without DSS treatments. However, histology results showed that AM attenuated DSS-induced inflammation and tissues damage in colons. Pro-inflammatory markers, COX2 and TNF-alpha were decreased at protein and mRNA levels in DSS-rats supplemented with AM, compared to DSS-rats on control diet.

Conclusions: Consumption of Atlantic mackerel at 1% or 5% protected rats from DSS-induced colonic damage and attenuated colonic inflammation.

Funding Sources: USDA NIFA 2022-67018-36235