Rising IL-18 levels linked to decreased carbohydrates tolerance in body

Bulgaria: A new study published in the Iranian Journal of Immunology shows that the ability to tolerate carbohydrates declines when IL-18 levels rise.

Due to the role of obesity in the rising incidence of associated comorbidities, such as insulin resistance and type 2 diabetes, it is one of the greatest health problems of the twenty-first century. Nedeva and colleagues consequently carried out this research to measure the IL-18 levels in individuals with the whole range of diabetic problems.

Growing research points to overnutrition as a key factor in the emergence of low-grade inflammation. Particularly, it is thought that persistent inflammation in adipose tissue is a significant risk factor for the onset of insulin resistance and type 2 diabetes in obese people. Adipose tissue inflammation still has many unknown causes. However, adipose tissue growth brought on by obesity offers a variety of intrinsic signals (such as adipocyte mortality, hypoxia, and mechanical stress) that might start the inflammatory response. Diabetes and persistent low-grade inflammation are linked. IL-18 activates many cell types and has pleiotropic effects as a pro-inflammatory cytokine. 

In this study, 387 Caucasians were separated into four groups: prediabetic patients, newly diagnosed type 2 diabetics, obese subjects without carbohydrate difficulties, and healthy controls.

The key findings of this study were as follows:

1. In comparison to the control group (219.47 ± 110.53 pg/ml), subjects with a body mass index of 30 kg/m2 and glycemic problems had significantly higher levels of IL-18 (249.77 ± 89.96 pg/ml, 259.01 ± 95.70 pg/ml, and 340.98 ± 127.65 pg/ml).

2. Additionally, whereas IL-18 was negatively correlated with HDL, it had substantial favorable relationships with a number of anthropometric measurements, liver enzymes, fasting glucose, insulin, uric acid, and triglycerides.

3. By using ROC analysis, it was possible to distinguish between participants with carbohydrate problems and those who had metabolic syndrome based on their circulating levels of IL-18.

4. The AUC for changes in glucose metabolism was 0.597, while the AUC for MS was 0.581.

Further research is necessary to determine the role of IL-18 in the development of diabetes mellitus and its effects concluded the Authors.

Reference:

Nedeva, I., Gateva, A., Assyov, Y., Karamfilova, V., Hristova, J., Yamanishi, K., Kamenov, Z., & Okamura, H. (2022). IL-18 Serum Levels in Patients with Obesity Prediabetes and Newly Diagnosed Type 2 Diabetes. Iranian Journal of Immunology, 19(2). https://doi.org/10.22034/iji.2022.90095.1987