Bariatric Surgery and Calcifediol Treatment, Gordian Knot of Severe-obesity-related Comorbidities Treatment

Background: Obesity (OB) is a chronic metabolic disease with important associated comorbidities and mortality. Vitamin D supplementation is frequently administered after bariatric surgery (BS), so as to reduce OB-related complications, maybe including chronic inflammation.

Aim: This study aimed to explore relations between vitamin D metabolites and components of the inflammasome machinery in OB before and after BS and their relations with the improvement of metabolic comorbidities.

Patients And Methods: Epidemiological/clinical/anthropometric/biochemical evaluation was performed in patients with OB at baseline and 6 months after BS. Evaluation of i) vitamin-D metabolites in plasma and ii) components of the inflammasome machinery and inflammatory-associated factors [NOD-like-receptors (NLRs), inflammasome-activation-components, cytokines and inflammation/apoptosis-related components, and cell-cycle and DNA-damage regulators] in peripheral blood mononuclear cells (PBMCs) was performed at baseline and 6 months after BS. Clinical and molecular correlations/associations were analyzed.

Results: Significant correlations between vitamin D metabolites and inflammasome-machinery components were observed at baseline, and these correlations were significantly reduced 6 months after BS in parallel to a decrease in inflammation markers, fat mass, and body weight. Treatment with calcifediol remarkably increased 25OHD levels, despite 24,25(OH)D remained stable after BS. Several inflammasome-machinery components were associated with improvement in metabolic comorbidities, especially hypertension and dyslipidemia.

Conclusion: The beneficial effects of vitamin D on OB-related comorbidities after BS patients are associated with significant changes in the molecular expression of key inflammasome-machinery components. The expression profile of these inflammasome components can be dynamically modulated in PBMCs after BS and vitamin D supplementation, suggesting that this profile could likely serve as a sensor and early predictor of the reversal of OB-related complications after BS.