Trans-palmitoleic acid does not modify the inflammasome expression in a rodent model of diet-induced obesity.

BACKGROUND: Metabolic disorders such as obesity and type 2 diabetes (T2D) coincide with an increased expression of pro-inflammatory factors. The NLRP3 inflammasome is a complex that activates the pro-inflammatory cytokine IL-1ß. (NOD-like receptor protein 3). Some nutrients, such as fatty acids, influence inflammatory processes. For example, in clinical studies, higher trans-palmitoyl acid (TP) concentrations coincide with lower adiposity and lower risk of developing T2D. This study aims to evaluate the effect of TP on NLRP3 expression in a rodent model of diet-induced obesity (DIO). METHODS: C57BL/6J mice were fed ad libitum with a control or a high-fat diet (HFD), added with or without TP (3 g/kg diet), for 11 weeks. IL-1ß was quantified in serum, and NLRP3-related gene expression was explored in epididymal adipose tissue. RESULTS: Despite increased weight gain in both high-fat groups, the high-fat TP group gained less weight than the high-fat group. In addition, NLRP3 and caspase-1 expression was higher in the HFD groups, but no differences were observed between the HFD and the HFD TP groups. Serum IL-1ß levels were not different among groups. CONCLUSIONS: Diet supplementation with TP prevents weight gain and has a neutral influence over NLRP3 expression and IL-1ß concentration in a DIO mice model.

INTRODUCCIÓN: Las alteraciones metabólicas como la obesidad y diabetes tipo 2 (DT2) coinciden con la expresión aumentada de factores proinflamatorios. Un complejo que induce la activación de la citocina proinflamatoria IL-1ß es el inflamasoma NLRP3 (NOD-like receptor protein 3). Algunos nutrimentos, como los ácidos grasos, influencian los procesos inflamatorios. Por ejemplo, en estudios clínicos, mayores concentraciones del ácido trans-palmitoléico (TP) coinciden con una menor adiposidad y un menor riesgo de desarrollar DT2. El objetivo de este estudio fue evaluar el efecto del TP sobre la expresión del inflamasoma NLRP3 en un modelo de obesidad inducida por dieta (OID) en roedores. MÉTODOS: Se alimentaron ratones C57BL/6J ad libitum con una dieta control o alta en lípidos (AL), adicionada o no con TP (3 g/kg dieta), durante 11 semanas. Se cuantificó la concentración de IL-1ß en elsuero de los animales, y en el tejido adiposo epididimal se midió la expresión de los componentes del inflamasoma. RESULTADOS: A pesar del aumento de peso en ambos grupos de dieta con alto contenido en lípidos, el grupo alto en lípidos TP ganó menos peso que el grupo AL. Por otro lado, la expresión de genes del inflamasoma resultó mayor en los grupos AL, pero no se encontraron diferencias entre los grupos AL y AL TP. Además, no se observaron diferencias en la concentración de IL-1ß en suero entre grupos. CONCLUSIONES: La dieta suplementada con TP previno el aumento del peso corporal, pero no modificó la expresión de los componentes del inflamasoma ni la concentración de IL-1ß en suero.

Trans-palmitoleic acid does not modify the inflammasome expression in a rodent model of diet-induced obesity / El ácido trans-palmitoléico no modifica la expresión del inflamasoma en un modelo murino de obesidad inducida por dieta

Abstract Background: Metabolic disorders such as obesity and type 2 diabetes (T2D) coincide with an increased expression of pro-inflammatory factors. The NLRP3 inflammasome is a complex that activates the pro-inflammatory cytokine IL-1β. (NOD-like receptor protein 3). Some nutrients, such as fatty acids, influence inflammatory processes. For example, in clinical studies, higher trans-palmitoyl acid (TP) concentrations coincide with lower adiposity and lower risk of developing T2D. This study aims to evaluate the effect of TP on NLRP3 expression in a rodent model of diet-induced obesity (DIO). Methods: C57BL/6J mice were fed ad libitum with a control or a high-fat diet (HFD), added with or without TP (3 g/kg diet), for 11 weeks. IL-1β was quantified in serum, and NLRP3-related gene expression was explored in epididymal adipose tissue. Results: Despite increased weight gain in both high-fat groups, the high-fat TP group gained less weight than the high-fat group. In addition, NLRP3 and caspase-1 expression was higher in the HFD groups, but no differences were observed between the HFD and the HFD TP groups. Serum IL-1β levels were not different among groups. Conclusions: Diet supplementation with TP prevents weight gain and has a neutral influence over NLRP3 expression and IL-1β concentration in a DIO mice model.

Resumen Introducción: Las alteraciones metabólicas como la obesidad y diabetes tipo 2 (DT2) coinciden con la expresión aumentada de factores proinflamatorios. Un complejo que induce la activación de la citocina proinflamatoria IL-1β es el inflamasoma NLRP3 (NOD-like receptor protein 3). Algunos nutrimentos, como los ácidos grasos, influencian los procesos inflamatorios. Por ejemplo, en estudios clínicos, mayores concentraciones del ácido trans-palmitoléico (TP) coinciden con una menor adiposidad y un menor riesgo de desarrollar DT2. El objetivo de este estudio fue evaluar el efecto del TP sobre la expresión del inflamasoma NLRP3 en un modelo de obesidad inducida por dieta (OID) en roedores. Métodos: Se alimentaron ratones C57BL/6J ad libitum con una dieta control o alta en lípidos (AL), adicionada o no con TP (3 g/kg dieta), durante 11 semanas. Se cuantificó la concentración de IL-1β en elsuero de los animales, y en el tejido adiposo epididimal se midió la expresión de los componentes del inflamasoma. Resultados: A pesar del aumento de peso en ambos grupos de dieta con alto contenido en lípidos, el grupo alto en lípidos TP ganó menos peso que el grupo AL. Por otro lado, la expresión de genes del inflamasoma resultó mayor en los grupos AL, pero no se encontraron diferencias entre los grupos AL y AL TP. Además, no se observaron diferencias en la concentración de IL-1β en suero entre grupos. Conclusiones: La dieta suplementada con TP previno el aumento del peso corporal, pero no modificó la expresión de los componentes del inflamasoma ni la concentración de IL-1β en suero.

Trans-palmitoleic acid reduces adiposity via increased lipolysis in a rodent model of diet-induced obesity.

Obesity is defined as increased adiposity, which leads to metabolic disease. The growth of adipose tissue depends on its capacity to expand through hyperplasia or hypertrophy, in order to buffer energy surplus. Also, during the establishment of obesity, adipose tissue expansion reflects adipose lipid metabolism (lipogenesis and/or lipolysis). It is well known that dietary factors can modify lipid metabolism promoting or preventing the development of metabolic abnormalities that concur with obesity. Trans-palmitoleic acid (TP), a biomarker of dairy consumption, has been associated with reduced adiposity in clinical studies. Thus, we aimed to evaluate the effect of TP over adiposity and lipid metabolism-related genes in a rodent model of diet-induced obesity (DIO). To fulfil this aim, we fed C57BL/6 mice with a Control or a High-Fat diet, added with or without TP (3 g/kg diet), during 11 weeks. Body weight and food intake were monitored, fat pads were weighted, histology of visceral adipose tissue was analysed and lipid metabolism-related gene expression was explored by qPCR. Results show that TP consumption prevented weight gain induced by high-fat diet, reduced visceral adipose tissue weight and adipocyte size, while increasing the expression of lipolytic molecules. In conclusion, we show for the first time that TP influences adipose tissue metabolism, specifically lipolysis, resulting in decreased adiposity and reduced adipocyte size in a DIO mice model.