Inhibition of Amino Acids Influx into Proximal Tubular Cells Improves Lysosome Function in Diabetes
Yuzuki Kano, Satoshi Yamaguchi, Koki Mise, Chieko Kawakita, Yasuhiro Onishi, Naoko Kurooka, Ryosuke Sugawara, Haya Hamed Hassan Albuayjan, Atsuko Nakatsuka, Jun Eguchi, Jun Wada- Psychiatry and Mental health
- Neuropsychology and Physiological Psychology
Background:
Inhibition of glucose influx into proximal tubular cells (PTCs) by sodium-glucose co-transporter 2 (SGLT2) inhibitors revealed prominent therapeutic impacts on diabetic kidney disease (DKD). Collectrin (CLTRN) serves as a chaperone for the trafficking of neutral amino acid transporters in the apical membranes of proximal tubular cells. We investigated the beneficial effects of reduced influx of amino acids into proximal tubular cells in diabetes and obesity model of Cltrn-/y mice.
Methods:
Cltrn+/y and Cltrn-/y mice at 5 weeks of age were assigned to standard diet- (STD) and streptozotocin and high fat diet-treated (STZ-HFD) groups.
Results:
At 22-23 weeks of age, body weight and HbA1c levels significantly increased in STZ-HFD-Cltrn+/y compared to STD-Cltrn+/y; however, they were not altered in STZ-HFD-Cltrn-/y compared to STZ-HFD-Cltrn+/y. At 20 weeks of age, urinary albumin creatinine ratio (UACR) was significantly reduced in STZ-HFD-Cltrn-/y compared to STZ-HFD-Cltrn+/y. Under the treatments with STZ and HFD, the
Conclusions:
The reduction of amino acids influx into proximal tubular cells inactivated mTOR, activated TFEB, improved lysosome function, and ameliorated vacuolar formation of PTCs in STZ-HFD-Cltrn-/y mice.