bioRxiv ScienceSearch

bioRxiv · 10.1101/800151

MetAP2 inhibition reduces food intake and body weight in a ciliopathy mouse model of obesity

Abstract

The ciliopathies Bardet-Biedl Syndrome and Alstrom Syndrome are genetically inherited pleiotropic disorders with primary clinical features of hyperphagia and obesity. Methionine aminopeptidase 2 inhibitors (MetAP2i) have been shown in preclinical and clinical studies to reduce food intake, body weight, and adiposity. Here we investigated the effects of MetAP2i administration in a mouse model of ciliopathy produced by conditional deletion of the Thm1 gene in adulthood (Thm1 cko). Thm1 cko mice show decreased hypothalamic pro-opiomelanocortin expression as well as hyperphagia, obesity, metabolic disease and hepatic steatosis. In obese Thm1 cko mice, two-week administration of MetAP2i reduced daily food intake and reduced body weight 17.1% from baseline (vs. 5% reduction for vehicle). This was accompanied with decreased levels of blood glucose, insulin and leptin. Further, MetAP2i reduced gonadal adipose depots and adipocyte size and improved liver morphology. This is the first report of MetAP2i reducing hyperphagia and body weight, and ameliorating metabolic indices in a mouse model of ciliopathy. These results support further investigation of MetAP2 inhibition as a potential therapeutic strategy for ciliary-mediated forms of obesity.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Pottorf, T. S., Fagan, M., Burkey, B., Cho, D. J., Vath, J. E., Tran, P. V.. 2019-10-13. MetAP2 inhibition reduces food intake and body weight in a ciliopathy mouse model of obesity. https://doi.org/10.1101/800151

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Lipid-ASO therapeutics exhibit differential tissue targeted delivery upon systemic or local CNS administration

Antisense oligonucleotides (ASOs) are a powerful therapeutic modality, but their full potential is hindered by pharmacokinetic properties that affect tissue and cellular delivery. Lipid conjugation is increasingly used to modulate ASO's biodistribution and promote extrahepatic activity, yet lipid dependent effects on in vivo functional delivery, particularly in the central nervous system (CNS), remain less explored. Here, we performed a side by side in vivo comparison of cholesterol, palmitic acid (C16:0), docosanoic acid (C22:0), and eicosapentaenoic acid (C20:5) conjugated to a fully phosphorothioated 3 10 3 LNA gapmer ASO targeting the Malat1 long non coding RNA. Lipid-ASO conjugates were administered systemically or locally in the brain of mice and evaluated for tissue level and cellular level distribution by imaging, qPCR and single-cell RNA sequencing, simultaneously annotating cell origin and global transcriptional changes within the cell. Following systemic administration in mice, lipid conjugation improved overall multi organ efficacy compared to unconjugated ASO, but with pronounced tissue specific differences. Single cell sequencing of liver and heart transcriptomes revealed lipid dependent cellular uptake patterns and transcriptional responses distinct from administration of unconjugated ASO. After intracerebroventricular administration, selected fatty acid conjugates enhanced silencing in deep brain regions such as the striatum, whereas cholesterol conjugation impaired functional delivery despite increased CNS retention. Light-sheet microscopy showed restricted parenchymal penetration of cholesterol ASOs compared with broader but heterogeneous distribution of palmitic acid conjugate. Together, these findings demonstrate that lipid identity critically determines ASO efficacy, productive cellular uptake, and regional CNS engagement, emphasizing the need for context specific lipid design in ASO therapeutic development.

pharmacology and toxicology

Novel Dissymmetric Ionizable Lipid-Assembled Lipid Nanoparticles for Delivery of Ferroptosis-Related siRNA in Diabetic Treatment

Small interfering RNA (siRNA) enables precise post-transcriptional gene silencing for refractory diseases, yet its clinical translation remains limited by the lack of safe and efficient delivery vectors. Inspired by the dissymmetric alkyl chain architecture of natural membrane phospholipids, we designed and synthesized 34 novel ionizable lipids with dissymmetric hydrophobic tails and formulated them into lipid nanoparticles (LNPs). Through systematic physicochemical and biological assessments, we established clear structure-activity relationships and identified two lead LNPs (O14-LNP, H18a-LNP) with superior endosomal escape capacity, enhanced in vivo gene silencing potency, and favorable biosafety relative to the clinical benchmark MC3-LNP. In both streptozotocin-induced and spontaneous db/db type 2 diabetes (T2D) mouse models, lead LNPs delivering ferroptosis-related siRNAs effectively ameliorated glucose and lipid metabolic disorders, restored islet function, and alleviated hepatic steatosis. This study not only lays a theoretical foundation for the rational design of novel ionizable lipids, but also validates the therapeutic potential of siRNA therapy targeting ferroptosis, providing a versatile delivery platform and targeted therapeutic strategy for the treatment of T2D.

pharmacology and toxicology

Pharmacological complementation remedies an inborn error of lipid metabolism

X-linked adrenoleukodystrophy (X-ALD) is a rare, genetic disease in which increased very long chain fatty acids (VLCFAs) in the central nervous system (CNS) cause demyelination and axonal degeneration, leading to severe neurological deficits. Sobetirome, a potent thyroid hormone agonist, has been shown to lower VLCFA levels in the periphery and CNS. In this study, two pharmacological strategies for enhancing the effects of thyromimetics were tested in Abcd1 KO mice, a murine model that has the same inborn error in metabolism as X-ALD patients. First, a sobetirome prodrug (Sob-AM2) with increased CNS penetration lowered CNS VLCFAs more potently than sobetirome, and was better tolerated with lower peripheral exposure, but was unable to unable to break the efficacy threshold of CNS VLCFA lowering in Abcd1 KO mice. Second, co-administration of thyroid hormone with sobetirome enhanced VLCFA lowering in the periphery compared to sobetirome alone but did not produce greater lowering in the CNS. These data suggest that the extent of CNS VLCFA lowering in Abcd1 KO mice is limited by a mechanistic threshold related to slow turnover kinetics, potentially related to the lack of frank X-ALD disease in this model. However, Sob-AM2 has improved potency at correcting the lipid abnormality associated with X-ALD in the CNS with better tolerance than the parent drug sobetirome.

pharmacology and toxicology