Abstract
BackgroundHigh concentrate (HC) diet-induced oxidative stress causes gut epithelial damages associated with apoptosis. Selenium (Se) being an integral component of glutathione peroxidase (GSH-Px) plays an important role in antioxidant defense system. Therefore, increasing dietary Se level would alleviate HC diet-induced injuries in gut mucosa. The present study investigated eighteen cross-bred goats, randomly divided into three groups (n = 6/group) fed either low concentrate (LC, roughage: concentrate ratio 65:35), high concentrate (HC, 35:65) or HC plus Se (HC-SY) diets for 10 weeks. Se was supplemented at the dose rate of 0.5 mg Se kg− 1 diet in the form of selenium yeast. The background Se level in HC and LC diets were 0.15 and 0.035 mg.kg− 1 diet, respectively. The Se at the dose of 0.115 mg.kg− 1 diet was added in LC diet to make its concentration equivalent to HC diet and with the supplementation of 0.5 mg Se kg− 1, the goats in group HC-SY received total Se by 0.65 mg.kg− 1 diet.ResultsThe molar concentrations of individual and total short chain fatty acids (TSCFA) significantly increased (P < 0.05) with simultaneous decrease in pH of colonic fluid in goats of HC and HC-SY groups compared with LC goats. HC diet induced loss of epithelial integrity, inflammation and loss of goblet cells in colonic mucosa associated with higher lipopolysaccharide (LPS) concentrations in colonic fluid whereas, the addition of SY in HC diet alleviated such damaging changes. Compared with LC, the HC diet elevated malondialdehyde (MDA) level with concurrent decrease in GSH-Px and superoxide dismutase (SOD) activities, while SY supplementation attenuated these changes and improved antioxidant status in colonic epithelium. Moreover, epithelial injury and oxidative stress in colon of HC goats were associated with increased apoptosis as evidenced by downregulation of bcl2 and upregulation of bax, caspases 3 and 8 mRNA expressions compared with LC goats. On contrary, addition of SY in HC (HC-SY) diet alleviated these changes by modulating expression of apoptotic genes in colonic epithelium.ConclusionsOur data suggest that supranutritional level of Se attenuates HC diet-induced oxidative stress and apoptosis and thereby minimizes the epithelial injury in colon of goats.
Highlights
High concentrate (HC) diet-induced oxidative stress causes gut epithelial damages associated with apoptosis
Fermentation pattern and LPS level in colon The molar concentrations of acetate, propionate, butyrate, total short chain fatty acids (TSCFA) and the acetate: propionate ratio significantly increased (P < 0.05) in colonic fluid of goats fed HC and HC-selenium yeast (SY) diets compared with those fed low concentrate (LC) diet (Table 1)
The pH of colonic fluid significantly decreased (P < 0.05) in HC and HC-SY compared with LC goats
Summary
High concentrate (HC) diet-induced oxidative stress causes gut epithelial damages associated with apoptosis. The existence of natural defensive mechanism to cope with increased acidity through microbial activities and buffering action from saliva in rumen is lacking in the large intestine. This condition makes the large intestine more prone to epithelial damage which causes LPS translocation and leads to systemic complications [9]. Goats were fed low concentrate (LC), high concentrate (HC) and HC plus selenium (HC-SY) diets for a period of 10 weeks. The severity of epithelial injury was graded as 0–3, from absent to mild (Superficial epithelial injury), moderate (Focal erosions), and severe (Multifocal erosions), the extent of inflammatory cell infiltrate was graded as 0–3, from absent to transmural, and goblet cell depletion was graded as 0–1 present or absent
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
