The main objective of this thesis is to improve the understanding of the role of helminth infections in the development of insulin resistance, hence type 2 diabetes, and to gain insight into the... Show moreThe main objective of this thesis is to improve the understanding of the role of helminth infections in the development of insulin resistance, hence type 2 diabetes, and to gain insight into the immunological mechanisms underlying this possible interaction. To this end, we initiated a large scale cluster randomized controlled trial, assessing the effect of anthelmintic treatment on insulin resistance and other metabolic, as well as immunological parameters, in a rural area of Indonesia. Deworming significantly reduced the prevalence of helminths, as well as infection intensity. Although treatment did not lead to an increase of whole-body insulin resistance at the community level, a significant increase in insulin resistance was observed among helminth-infected subjects. Furthermore, by comparing immune cells of helminth-infected Indonesians before and after treatment, we gained insight into the specific cell populations that participate in the type 2 and regulatory networks, and show that treatment affects specific cell subsets in these networks. Altogether, the studies described in this thesis show that helminth infections in humans, as well as the administration of helminth molecules in obese mice, have a beneficial effect on the insulin sensitivity, and have shed light on the immunomodulatory effects of helminths. Show less
The main objective of this thesis is to improve understanding of the role of helminth infections in the development of insulin resistance (IR), hence Type 2 Diabetes (T2D), in the light of... Show moreThe main objective of this thesis is to improve understanding of the role of helminth infections in the development of insulin resistance (IR), hence Type 2 Diabetes (T2D), in the light of increasing urbanization in Indonesia. Our large-scale cluster-randomized controlled trial was performed in a rural area of Indonesia, which is endemic for soil-transmitted helminth (STH), and has been previously reported to have a low prevalence of IR and T2D. In STH-infected subjects, as assessed by microscopy, 12-month anthelmintic treatment increased IR, which was mediated by an increase in BMI and leptin to adiponectin ratio, as well as reduction in eosinophil count. Next, we also aimed to assess the different metabolic profile between populations living in rural and urban area, and to study the relative protective effect of rural environment to high-fat diet (HFD). In comparison to those living in rural area, individuals living in urban area had higher whole body IR, which was mainly mediated by the higher adiposity and leptin level, which were progressively increased with increased duration of time spent in urban area. Different environmental factors (including past or current exposure to STH) did not seem to affect the metabolic response to HFD intervention, independent from adiposity. Show less
