Tea polyphenols protect bovine intestinal epithelial cells from the adverse effects of heat-stress in vitro

Abstract

Heat-stress (HS) leads to impaired gut health, adversely affecting milk production of dairy cows. In the present study, we investigated the protective effects of tea polyphenols (TP) against HS-induced damage in bovine intestinal epithelial cells (BIECs) and explored the underlying mechanisms. Primary BIECs were isolated from bovine duodenum, cultured and treated as follows: (1) control cells incubated in complete medium at 37 °C for 12 h, (2) TP group incubated in medium containing 100 μg/mL TP at 37 °C for 12 h, (3) HS group incubated in medium at 37 °C for 6 h followed by 6 h at 42 °C, and (4) HS + TP group incubated with 100 μg/mL TP for 6 h at 37 °C and 6 h at 42 °C. TP improved cell viability and antioxidant capacity, and decreased apoptosis and LDH activity. TP led to upregulation of Nrf2 and its target antioxidant genes HO-1, NQO1 and SOD1 expression. TP significantly decreased the expression of proinflammatory cytokine genes (NF-κB, IL-6 and TNF-α), and increased expression of the anti-inflammatory cytokine gene, IL-10. The above results suggested that TP protected BIECs from HS-induced adverse effects by alleviating oxidative stress and inflammatory responses, indicating that TP can alleviate HS-induced intestinal damage in dairy cows.

Keywords:

• Antioxidant
• apoptosis
• bovine enterocyte
• inflammation
• tea polyphenols
• thermal stress

Ethics approval

International, national and/or institutional rules for animal care and usage were adhered to.

Author contribution

SDM designed this study, and performed major parts of the experiments, YSA wrote the manuscript. SW, QS and MYD helped in experimental design. HWW participated in the interpretation of our results. CZ and LH developed the concept and provided guidance during the study.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was funded by the National Natural Science Foundation of China (31872537; 31402263) and the National Key R&D Program of China (2017YFE0129900).