Work

Adipose tissue IL‐18 production is independent of caspase‐1 and caspase‐11

Year: 2024

Type: article

Abstract: BACKGROUND: Inflammation in adipose tissue, resulting from imbalanced caloric intake and energy expenditure, contributes to the metabolic dysregulation observed in obesity. The production of inflammatory cytokines, such as IL-1β and IL-18, plays a key role in this process. While IL-1β promotes insulin resistance and diabetes, IL-18 regulates energy expenditure and food intake. Previous studies have suggested that caspase-1, activated by the Nlrp3 inflammasome in response to lipid excess, mediates IL-1β production, whereas activated by the Nlrp1b inflammasome in response to energy excess, mediates IL-18 production. However, this has not been formally tested. METHODS: Wild-type and caspase-1-deficient Balb/c mice, carrying the Nlrp1b1 allele, were fed with regular chow or a high-fat diet for twelve weeks. Food intake and mass gain were recorded weekly. At the end of the twelve weeks, glucose tolerance and insulin resistance were evaluated. Mature IL-18 protein levels and the inflammatory process in the adipose tissue were determined. Fasting lipid and cytokine levels were quantified in the sera of the different experimental groups. RESULTS: We found that IL-18 production in adipose tissue is independent of caspase-1 activity, regardless of the metabolic state, while Nlrp3-mediated IL-1β production remains caspase-1 dependent. Additionally, caspase-1 null Balb/c mice did not develop metabolic abnormalities in response to energy excess from the high-fat diet. CONCLUSION: Our findings suggest that IL-18 production in the adipose tissue is independent of Nlrp3 inflammasome and caspase-1 activation, regardless of caloric food intake. In contrast, Nlrp3-mediated IL-1β production is caspase-1 dependent. These results provide new insights into the mechanisms underlying cytokine production in the adipose tissue during both homeostatic conditions and metabolic stress, highlighting the distinct roles of caspase-1 and the Nlrp inflammasomes in regulating inflammatory responses.

Source: Immunity Inflammation and Disease

DOI: 10.1002/iid3.1241

Authors: Luis Román‐Domínguez, Jonathan Salazar‐León, Karla F. Meza‐Sosa, Leonor Pérez‐Martínez, Gustavo Pedraza‐Alva

Institution: Universidad Nacional Autónoma de México

Language: English

Topic: Adipokines, Inflammation, and Metabolic Diseases

Subfield: Endocrinology, Diabetes and Metabolism

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,240