Research advancements in the association between prevalent trace metals and connective tissue diseases

Connective tissue diseases (CTD) encompass a spectrum of autoimmune disorders, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sjogren's syndrome (SS), inflammatory myopathy (IIM), systemic sclerosis (SSc), among others. Recent research has highlighted the significant role of trace metals in the pathogenesis of connective tissue diseases. This article provides an overview of recent advancements in understanding the correlation between common trace metals such as iron, copper, zinc and CTD, aiming to offer novel insights for the diagnosis and treatment of these conditions. Iron is implicated in the pathogenesis of SLE through various mechanisms, including alterations in serum iron concentration, disturbances in iron metabolism and homeostasis, as well as involvement in ferroptosis. Disorders affecting iron metabolism, ferroptosis, and the expression and regulation of associated genes and proteins contribute to the development and progression of RA. Elevated serum copper levels are observed in patients with both SLE and RA compared to healthy controls. Cuproptosis, a novel form of cell death, is also considered to be linked to their pathogenesis. Decreased serum zinc concentration is evident in patients with SLE, RA, and SS. Zinc finger proteins play a crucial role in the pathogenesis of these diseases.