Can parasites influence insulin signaling and development of diabetes mellitus?

While type 2 diabetes mellitus (T2DM) is a global health challenge, parasitic infections are prevalent in tropical and subtropical regions. There is evidence of a complex relationship between schistosomiasis and T2DM, implicating helminth infections as potential modulators of diabetes and metabolic syndrome. It was observed that individuals with a history of schistosomiasis had lower prevalence of diabetes, insulin resistance, and metabolic syndrome. Mechanistic explanations suggest that helminths modulate host immunity, skewing responses towards an anti-inflammatory phenotype (Th2 cytokine dominance) and promoting regulatory macrophage populations (M2-like phenotype). Such immune modulation may prevent inflammation-driven insulin resistance, a hallmark of T2DM. Additionally, helminth infections influence host lipid metabolism and gut microbiota, both crucial for metabolic regulation. Despite largely protective findings, some reports present contrasting associations, underscoring the complexity of helminth–host metabolic interactions. Current research is focused on harnessing helminth-derived immunomodulatory molecules and excretory–secretory products as novel therapeutic agents for metabolic diseases. Clinical trials using controlled helminth infections have shown preliminary metabolic benefits, though significant clinical, cultural, and regulatory barriers remain. Overall, elucidating the intricate interplay between helminthic infections and T2DM opens promising therapeutic avenues, potentially redefining approaches for preventing and managing metabolic diseases.