Helminth infection modulates number and function of adipose tissue Tregs in high fat diet-induced obesity

Abstract

Background Epidemiological and experimental studies have shown a protective effect of helminth infections in weight gain and against the development of metabolic dysfunctions in the host. However, the mechanisms Treg cells exert in the helminth-obesity interface has been poorly investigated. The present study aimed to verify the influence of Heligmosomoides polygyrus infection in early stages of high fat diet-induced obesity. Principal findings The presence of infection was able to prevent exacerbated weight gain in mice fed with high fat diet when compared to non-infected controls. In addition, infected animals displayed improved insulin sensitivity and decreased fat accumulation in the liver. Obesity-associated inflammation was reduced in the presence of infection, demonstrated by lower levels of leptin and resistin, lower infiltration of Th1 and Th17 cells in adipose tissue, higher expression of IL10 and adiponectin, increased infiltration of Th2 and eosinophils in adipose tissue of infected animals. Of note, the parasite infection was associated with increased Treg frequency in adipose tissue which showed higher expression of cell surface markers of function and activation, like LAP and CD134. The infection could also increase adipose Treg suppressor function in animals on high fat diet. Conclusion These data suggest that H. polygyrus modulates adipose tissue Treg cells with implication for weight gain and metabolic syndrome.

Helminth infection and helminth-derived products: A novel therapeutic option for non-alcoholic fatty liver disease

“…Treg frequency and suppressor function in adipose tissue increased after H. polygyrus infection. H. polygyrus contributed to improve weight gain and MetS by regulating adipose tissue Tregs in obese mice ( 110 ). N. brasiliensis infection increased IL-5 and IL-13 levels in visceral adipose tissue (VAT) and promoted insulin sensitivity in HFD mice.…”

The Roles of Various Immune Cell Populations in Immune Response against Helminths

“…On the other hand, while helminths have a negative impact, they may also be beneficial for humans by alleviating the symptoms of diet-induced insulin resistance [ 21 ], colitis [ 22 ], Crohn’s disease [ 23 ], and reducing allergic symptoms through an IL-10-dependent mechanism [ 24 ]. This review provides a concise overview of the mechanisms involved in the recognition of helminths by host cells and the roles of various cell types, including macrophages, tuft cells, T and B lymphocytes, eosinophils, basophils, neutrophils, innate lymphoid cells type 2 (ILC2), and mast cells.…”