Inhibition of Oxidative Stress-Induced Ferroptosis Can Alleviate Rheumatoid Arthritis in Human.

Rheumatoid arthritis (RA) is a chronic autoimmunity illness, mainly featured with synovitis of the joint. The specificity of ferroptosis is disparate in different diseases, and the mechanism of ferroptosis in RA has some uncertainty yet. Therefore, the mechanism of ferroptosis was deeply observed in RA patients and animal models. In this paper, plasma of RA patients, the tumor necrosis factor-alpha-induced human synovial fibroblasts, and an animal model of arthritis induced by collagen were applied to initially inquire about the therapeutic effect of ferroptosis. For the RA patients, ELISA detected protein expression of glutathione (GSH), GPX4, Nrf2, Keap-1, and ferritin. In cell experiments, erastin or fer-1 regulated the invasion of human synovial fibroblast cells, mitochondrial membrane potential, reactive oxygen species (ROS) expression, marker protein, and so on. For the animal experiments, 32 Sprague-Dawley male rats were randomly separated into four groups with a collagen-induced RA model for 14 days and administered with erastin or fer-1 for 35 days. The expressions of GSH, GPX4, Nrf2, and Keap-1 were lower, and the ferritin was higher in RA patients, and the expressions of these proteins varied significantly after disease remission. In addition, ferroptosis inactivation also reduced the proliferation and migration ability, mitochondrial membrane potential, and ROS in cells. We discovered unexpectedly that activation of ferroptosis meaningfully forbore the foot swelling in animals with CIA, reduced arthritis scores, destruction of bone, and articular synovitis, and also decreased the high expression of inflammatory factors in plasma. There is a nonlinear relationship between human disease manifestations and animal model pathology. Ferroptosis regulating in RA for humans or animals may produce different effects.