Ameliorative effects of riboflavin on acetic acid‐induced colonic injury in rats

Abstract

Riboflavin (RF) has been found to be a promising antioxidant and/or anti-inflammatory agent in several studies. However, the effect of RF against acetic acid (AA)-induced colonic injury is currently unknown. This study aimed to investigate the potential antioxidant and protective effects of RF in a rat model of ulcerative colitis. Starting immediately after the colitis induction (AA+RF group) or 1 week before the colitis induction (RF+AA+RF group), the rats were treated with RF (25 mg/kg per day; p.o.) for 3 days. The control and AA groups received saline (1 mL; p.o.) whereas AA+SS group (positive control) received sulfasalazine (100 mg/kg per day; p.o.) for 3 days. Colonic samples were taken for the biochemical and histological assessments on the third day. High damage scores, elevated tissue wet weight index (WI), tissue myeloperoxidase (MPO) activity, 8-hydroxy-2'-deoxyguanosine levels and chemiluminescence values, and a pronounced decrease in antioxidant glutathione (GSH) levels of the AA group were all reversed by RF pretreatment (RF+AA+RF group) and SS treatment (AA+SS group) (P < .05-.001). Tissue WI, MPO activity and GSH levels were not statistically changed in the AA+RF group. Western blot analysis revealed that the decreased protein expressions of tissue collagen (COL) 1A1, COL3A1 and transforming growth factor-β1 in the AA group were elevated in all the treatment groups (P < .05-.001). In conclusion, RF exerts both the antioxidant and anti-inflammatory effects against AA-induced colonic inflammation by suppressing neutrophil accumulation, inhibiting reactive oxidant generation, preserving endogenous glutathione, improving oxidative DNA damage and regulating inflammatory mediators, suggesting a future potential role in the treatment and prevention of ulcerative colitis.

Resveratrol modulates the gut microbiota to prevent murine colitis development through induction of Tregs and suppression of Th17 cells

“…B. acidifaciens is also known to increase SCFA production of acetic and succinic acids, both of which can contribute to colitis‐associated inflammation. Acetic acid, given in high concentrations, can induce colitis in murine models . Succinic acid, which is produced by members of Bacteroidacea e, such as B. acidifaciens , was found to be increased in the colons of colitis‐induced mice and when administered by enemas can produce ulcers in the colon .…”

“…Acetic acid, given in high concentrations, can induce colitis in murine models. 57 Succinic acid, which is produced by members of Bacteroidaceae, such as B. acidifaciens, was found to be increased in the colons of colitis-induced mice and when administered by enemas can produce ulcers in the colon. 58 B. acidifaciens resembles closely another member of the same genus B. fragilis, and these bacteria have been shown in the literature to trigger a strong inflammatory cascade response, including activation of IL-17dependent pathways.…”

The effects of riboflavin on ischemia/reperfusion induced renal injury: Role on caspase-3 expression

“…8-OHdG, which is formed by the reaction of OH radical, the strongest reactive oxygen species, with guanine base, is known as an indicator of oxidative DNA damage [21]. Various studies have shown that oxidative stress increases the formation of 8-OHdG [21,22]. In this study, ischemia/reperfusion in kidney tissues increased oxidative DNA damage as assessed by increased 8-OHdG levels while this increase is reversed by riboflavin treatment.…”

“…DNA damage is induced by cellular metabolites such as ROS or exogenous agents and may be cause mutation, aging or death of cell. 8-OHdG, which is formed by the reaction of OH radical, the strongest reactive oxygen species, with guanine base, is known as an indicator of oxidative DNA damage [21]. Various studies have shown that oxidative stress increases the formation of 8-OHdG [21,22].…”

The potential anti-inflammatory effect of Omega-3 polyunsaturated fatty acids on experimentally induced ulcerative colitis in rats

“…Because of the importance of excess and uncontrollable Reactive Oxygen Species (ROS) in the pathogenesis of ulcerative colitis, the value to determine free radical scavenger such as reduced Glutathione. The endogenous antioxidant GSH was reduced significantly in the colonic tissues of the acetic acid-induced ulcerative colitis in rats (Karakoyun et al, 2018). Colon Caspase-3 levels were higher in the colitis than in the control group rats (Akcan et al, 2008).…”