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Stockmans, I.

Publications and source records attributed to Stockmans, I..

2 recordsLinked to original sources

A dietary intervention following incretin analog treatment restores adipose tissue functions in diet-induced obese mice

Obesity affects more than 15% of the world population and is associated with the development of glucose intolerance and type 2 diabetes. In recent years, incretin analogs are prescribed at a high rate for treatment of obesity and diabetes due to their potent effects on lowering bodyweight and improving glucose homeostasis. However, recent studies suggest that many patients do not stay on incretin analog therapy and thereby rapidly regain bodyweight. The non-compliance of patients to incretin analog therapy is not only due to drug shortage but also insufficient knowledge on the long-term effects of the therapy. To address this knowledge gap and provide a long-term therapy strategy for obesity, we examined the effects of incretin analog treatment and withdrawal on adipose tissue functions in diet-induced obese mice. Our transcriptome data suggest that incretin analog treatment restored most of obesity-mediated deregulated gene expression in adipose tissue. However, genes encoding lipogenic enzymes, downregulated by diet-induced obesity, were not restored by incretin analog treatment. Upon therapy withdrawal, mice displayed rapid bodyweight regain, impaired adipose tissue function, and glucose intolerance. In contrast, a dietary intervention following incretin analog therapy withdrawal restored lipogenic gene expression in adipose tissue, maintained glucose homeostasis, increased lean mass and minimized body weight regain. Our findings revealed the effects of incretin analog therapy and therapy withdrawal on adipose tissue and highlight the importance of a dietary intervention following incretin analog therapy, which may contribute to the development of long-term therapy guidelines of incretin analog therapy for patients with obesity.

physiology↗

MLX phosphorylation stabilizes the ChREBP-MLX heterotetramer on tandem E-boxes to control carbohydrate and lipid metabolism

The heterodimeric ChREBP-MLX transcription factor complex is a key mediator that couples intracellular sugar levels to carbohydrate and lipid metabolism. To promote the expression of target genes, two ChREBP-MLX heterodimers form a heterotetramer to bind a tandem element with two adjacent E-boxes, called Carbohydrate Responsive Element (ChoRE). How the ChREBP-MLX hetero-tetramerization is achieved and regulated, remains poorly understood. Here we show that MLX phosphorylation on an evolutionarily conserved motif is necessary for the heterotetramer formation on the ChoRE and the transcriptional activity of the ChREBP-MLX complex. We identified CK2 and GSK3 as MLX kinases that coordinately phosphorylate MLX. High intracellular glucose-6-phosphate accumulation inhibits MLX phosphorylation and heterotetramer formation on the ChoRE, impairing ChREBP-MLX activity. Physiologically, MLX phosphorylation is necessary in Drosophila to maintain sugar tolerance and lipid homeostasis. Our findings suggest that MLX phosphorylation is a key mechanism for the ChREBP-MLX heterotetramer formation to regulate carbohydrate and lipid metabolism.

cell biology↗