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Deletion of glycerol channel aquaporin-9 (Aqp9) impairs long-term blood glucose control in C57BL/6 leptin receptor-deficient (db/db) obese mice

ABSTRACT: Deletion of the glycerol channel aquaporin-9 (Aqp9) reduces postprandial blood glucose levels in leptin receptor deficient (db/db) obese mice on a C57BL/6×C57BLKS mixed genetic background. Furthermore, shRNA mediated reduction of Aqp9 expression reduces liver triacylglycerol (TAG) accumulation in a diet induced rat model of obesity. The aim of this study was to investigate metabolic effects of Aqp9 deletion in coisogenic db/db mice of the C57BL/6 background. Aqp9wt db/db and Aqp9-/- db/db mice did not differ in body weight and liver TAG contents. On the C57BL/6 genetic background we observed elevated plasma glucose in Aqp9-/- db/db mice (+ 1.1 mM, life-time average) while plasma insulin concentration was reduced at time of death. Glucose levels changed similarly in pentobarbital anesthetized, glucagon challenged Aqp9wt db/db and Aqp9-/- db/db mice. Liver transcriptional profiling did not detect differential gene expression between genotypes. Metabolite profiling revealed a sex independent increase in plasma glycerol (+55%), glucose (+24%) and reduction in threonate (all at q<0.1) in Aqp9-/- db/db mice compared to controls. Metabolite profiling thus confirms a role of AQP9 in glycerol metabolism of obese C57BL/6 db/db mice. In this animal model of obesity Aqp9 gene deletion elevates plasma glucose and does not alleviate hepatosteatosis.

INSTRUMENT(S): LECO Pegasus III

PROVIDER: MTBLS219 | MetaboLights | 2015-09-28

REPOSITORIES: MetaboLights

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Deletion of glycerol channel aquaporin-9 (Aqp9) impairs long-term blood glucose control in C57BL/6 leptin receptor-deficient (db/db) obese mice.

Spegel Peter P Chawade Aakash A Nielsen Søren S Kjellbom Per P Rützler Michael M

Physiological reports 20150901 9

Deletion of the glycerol channel aquaporin-9 (Aqp9) reduces postprandial blood glucose levels in leptin receptor-deficient (db/db) obese mice on a C57BL/6 × C57BLKS mixed genetic background. Furthermore, shRNA-mediated reduction of Aqp9 expression reduces liver triacylglycerol (TAG) accumulation in a diet-induced rat model of obesity. The aim of this study was to investigate metabolic effects of Aqp9 deletion in coisogenic db/db mice of the C57BL/6 background. Aqp9(wt) db/db and Aqp9(-/-) db/db ...[more]

PMID: 26416971

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