Effects of hesperidin on mitochondrial function, mitochondria-associated endoplasmic reticulum membranes and IP3R–MCU calcium axis in the intestine of piglets exposed to deoxynivalenol

Abstract

Deoxynivalenol (DON) pollution is prevalent in crops, and can induce oxidative stress and intestinal injury. Hesperidin is one of the major flavonoids in citrus fruits that has various biological activities such as antioxidant and anti-inflammatory activities. However, whether hesperidin could alleviate DON-induced intestinal injury and the mechanism remain unclear. Mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) have attracted attention for their crucial signaling points to regulate ER–mitochondria calcium transfer. This study aims to evaluate the effects of hesperidin on the intestinal barrier, mitochondrial function, MAMs, and inositol 1,4,5-triphosphate receptor (IP3R)–mitochondrial calcium uniporter (MCU) calcium axis in the intestine of piglets exposed to DON. Twenty-four piglets were randomly divided into four groups in a 2 × 2 factorial arrangement for a 21-d experiment: Control: basal diet; hesperidin group: basal diet + 300 mg kg⁻¹ hesperidin; DON: basal diet + 1.5 mg kg⁻¹ DON; DON + hesperidin group: basal diet + 1.5 mg kg⁻¹ DON + 300 mg kg⁻¹ hesperidin. The data showed that when compared with the DON group, hesperidin improved growth performance and the intestinal barrier, alleviated intestinal oxidative stress and ER stress, and decreased the serum alanine aminotransferase (ALT) level (P < 0.05). Hesperidin also alleviated mitochondrial dysfunction and ferroptosis in the intestine of piglets exposed to DON (P < 0.05). Importantly, hesperidin prevented excessive MAM formation by downregulating the protein levels of Mitofusin 2 (Mfn2) and glucose-regulated protein 75 (GRP75), decreasing the ratio of the mitochondria with MAMs/total mitochondria and the ratio of MAM length/mitochondrial perimeter and lengthening the mitochondria–ER distance in MAMs (P < 0.05). Furthermore, hesperidin regulated the IP3R-glucose-regulated protein 75 (GRP75)–voltage-dependent anion channel 1 (VDAC1)–MCU calcium axis by decreasing the protein levels of GRP75 and MCU and the calcium level of the mitochondria compared with the DON group (P < 0.05). An in vitro experiment was conducted to further explore whether IP3R-mediated ER–mitochondria calcium transfer was involved in the protective effects of hesperidin on the intestinal epithelium barrier and mitochondria. Data showed that hesperidin may exert protective effects on the intestinal epithelium barrier and mitochondria via inhibiting ER–mitochondrial calcium transfer mediated by IP3Rs. These data suggested that hesperidin could alleviate MAM-mediated mitochondrial calcium overload, thereby improving mitochondrial function and alleviating oxidative stress and intestinal injury in DON-challenged piglets.