Discrepancy between clinical and histological effects of DHA supplementation in a rat model of pouchitis

Abstract

Docosahexaenoic acid (DHA) potentially modulates inflammatory processes. Therefore, the aim of this study was to determine the influence of DHA supplementation on the expression of intestinal inflammation and nutritional status in rats which have undergone restorative proctocolectomy. Twenty-four Wistar rats were operated. After the induction of pouchitis, animals were randomly divided into a control group (CG) and supplementation groups receiving respectively a semi-synthetic diet without or with DHA (in a lower or higher dose, respectively known as the lower dose, LD, and higher dose, HD, groups) for six weeks. Selected nutritional parameters were assessed. Histopathological and immunohistochemical analysis of pouch mucosa specimens was also performed. The effectiveness of feeding and quality of stools were significantly better in the HD group than in the CG. The intensity of inflammation (Moskovitz scale) was higher in HD and LD than in CG (p = 0.03 and p = 0.0006, respectively). Nevertheless, pouch adaptation (Laumonier scale) was more significant in LD than in CG (p = 0.007). On the other hand, tissue expression of IL-1a and IL-10 was higher in HD and LD than in CG (IL-1a, p = 0.009 and p = 0.05, respectively; IL-10, p = 0.04 for both). DHA supplementation has no impact on body weight gain. Yet it seems that it may improve the effectiveness of nutrition and stool quality in rats which have undergone restorative proctocolectomy. Simultaneously, it increases the intensity of pouch adaptation and inflammation. The specificity of observed changes is not clear. However, it may imply potential modulation of inflammatory processes of pouch mucosa.

Comparison of Dietary Oils with Different Polyunsaturated Fatty Acid n-3 and n-6 Content in the Rat Model of Cutaneous Wound Healing

“…Fish oil was also assessed as less suitable in comparison to olive oil during the healing of excisional lesions in mice due to reduced wound contraction, slower re-epithelialization, lower hydroxyproline level, and blood vessels density [18]. Higher intensity of inflammation (in comparison with the control) was also observed in the DHA-fed group of rats that underwent restorative proctocolectomy [19]. On the other hand, DHA exhibited anti-oxidative, anti-inflammatory and anti-fibrotic characteristics due to its ability to reduce TGF-β1 (including its fibrogenic potential), IL-1β and collagen expression, and to decrease the α-SMA (smooth muscle actin)-positive matrix in cholestatic liver injury in rats [20].…”

Trace elements and rat pouchitis.

“…The feeding of rats was maintained at the 25 g/d level for 11 following days. Subsequently, inflammation of J-pouch was induced following a procedure developed in our previous studies (Drzymała-Czyż et al, 2012). For that purpose, the animals were given fiber-enriched AIN-93 diet for seven days (with growing fiber quantities, 1% on the first day, 2% on the second, up to a maximum of 4% of the content).…”

Pouchitis Is Associated with Paneth Cell Dysfunction and Ameliorated by Exogenous Lysosome in a Rat Model Undergoing Ileal Pouch Anal Anastomosis

“…Weight changes and fecal scores were recorded daily. The fecal score was scored according to the previous study [16]. Briefly, a lack of stool was scored as 1, diarrhea as 2, a blob of stool as 3, textured stool as 4, and normal stool as 5.…”