Keratinocyte growth factor ameliorates mycophenolate mofetil-induced intestinal barrier disruption in mice

Abstract

Objectives: Although mycophenolate mofetil-induced (MMF) effectively improves long-term graft survival, the gastrointestinal (GI) side effects due to MMF-induced GI barrier damage limit its use in clinic. Keratinocyte growth factor (KGF) plays a crucial role in the intestinal protection and repair process. This study is designed to investigate the protective effect of KGF on MMF-induced intestinal mucosal barrier disruption and the potential mechanism.

Methods: Thirty adult male C57BL/6 mice were assigned to one of the following groups: the MMF group, the MMF + KGF group, and the control group (n = 10 in each group). Animals in the MMF group received MMF (500 mg/kg) by gavage once daily for 15 consecutive days; animals in the MMF + KGF group received MMF (500 mg/kg) by gavage and KGF (5 mg/kg) by intraperitoneal injection once daily for 15 consecutive days; and control mice were given an equal volume of vehicle during the 15-day experimental period. In each group, intestinal paracellular permeability, histopathological changes and shifts in tight junction (TJ) protein were evaluated; further, proliferation and apoptosis of intestinal epithelial cells (IECs) were assessed, and intraepithelial lymphocytes (IELs) were isolated and analyzed by flow cytometry.

Results: MMF caused intestinal mucosal injury, increased intestinal mucosal permeability, and altered expression of TJ protein. Moreover, MMF treatment inhibited IEC proliferation and increased apoptosis. MMF treatment resulted in a lower proportion of γδ⁺ T cells in IELs (γδ⁺ IELs). Conversely, concurrent administration of KGF with MMF effectively alleviated MMF-induced intestinal mucosal disruption, inhibited the increase in intestinal permeability, and maintained TJ protein expression. KGF also reversed the MMF-mediated inhibition of proliferation and promotion of apoptosis in IECs. In addition, KGF significantly enhanced the proportion of γδ⁺ IELs.

Conclusion: Our findings suggest that MMF induces intestinal epithelial barrier disruption in mice. KGF may play a protective role to ameliorate the disruption and provide a therapeutic intervention for gastrointestinal disorders induced by MMF.

Keywords: Gastrointestinal side effect; Keratinocyte growth factor; Mycophenolate mofetil; γδ+intraepithelial lymphocyte.