Inhibition of calcium imbalance protects hepatocytes from vanadium exposure-induced inflammation by mediating mitochondrial-associated endoplasmic reticulum membranes in ducks

Abstract

Vanadium (V) is an essential mineral element in animals, but excessive V can lead to many diseases, affecting the health of humans and animals. However, the molecular crosstalk between mitochondria-associated endoplasmic reticulum membranes (MAMs) and inflammation under V exposure is still at the exploratory stage. This study was conducted to determine the molecular crosstalk between MAMs and inflammation under V exposure in ducks. In this study, duck hepatocytes were treated with NaVO₃ (0 μM, 100 μM, and 200 μM) and 2-aminoethyl diphenyl borate (2-APB) (IP₃R inhibitor) alone or in combination for 24 h. The data showed that V exposure-induced cell vacuolization, enlarged intercellular space, and decreased density and viability. Meanwhile, hydrogen peroxide (H₂O₂), malonaldehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and reactive oxygen species (ROS) levels were upregulated under V treatment. In addition, excessive V could lead to a marked reduction in the MAMs structure, destruction of the membrane structure and overload of intracellular Ca²⁺ and mitochondrial Ca²⁺. Moreover, V treatment resulted in notable upregulation of the levels of MAMs-relevant factors (IP₃R, Mfn2, Grp75, MCU, VDAC1) but downregulated the levels of IL-18, IL-1β, and lactate dehydrogenase (LDH) in the cell supernatant. Additionally, it also significantly elevated the levels of inflammation-relevant factors (NLRP3, ASC, caspase-1, MAVS, IL-18, IL-1β, and TXNIP). However, the inhibition of IP₃R expression attenuated the V-induced variations in the above indicators. Collectively, our results revealed that the maintenance of calcium homeostasis could protect duck hepatocytes from V-induced inflammation injury via MAMs.