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Sodium glucose cotransporter-2 (SGLT2) inhibitors are widely used for diabetes treatment. Although SGLT2 inhibitors have been clinically observed to increase food intake, roles or even the presence of SGLT2 in the central nervous system (CNS) has not been established. We aimed to elucidate potential functions of SGLT2 in the CNS, and the effects of CNS-targeted SGLT2 inhibitors on food intake. We administered three kinds of SGLT2 inhibitors, tofogliflozin, dapagliflozin, and empagliflozin, into the lateral ventricle (LV) in rats and evaluated their effects on food intake. Bolus ICV SGLT2 inhibitor induced an increase in food intake. Tofogliflozin had the strongest effect among these drugs. No effect was observed when the same dose of tofogliflozin was administered intraperitoneally. We also evaluated the effects of tofogliflozin administration in the third (3V) and fourth ventricle (4V). Food intake was most markedly enhanced when tofogliflozin was infused into the LV. Fewer or no effects were observed with infusion into the 3V or 4V, respectively. Intraperitoneal administration of liraglutide, a GLP-1 receptor agonist known to suppress food intake, was combined with central tofogliflozin to elucidate whether GLP-1 signaling antagonizes the effect of central SGLT2 inhibitors on food intake. Systemic administration of liraglutide suppressed the effect of ICV tofogliflozin on food intake. To elucidate potential molecular mechanisms mediating changes in feeding, hypothalamic areas associated with food intake regulation were harvested and analyzed after intracerebroventricular administration (ICV) of tofogliflozin. ICV tofogliflozin increased phosphorylation of AMPK in the lateral hypothalamus. In conclusion, SGLT2 activity in the CNS may regulate food intake through AMPK phosphorylation in the lateral hypothalamic area. Disclosure K. Takeda: None. H. Ono: None. T. Ohno: None. K. Yokote: None. Funding Japan Society for the Promotion of Science (15K09398, 18K08502, 20H00524); Japan Agency for Medical Research and Development (17GM5010002H0001, 18GM5010002H0002, 19GM5010002H0003, 20GM5010002H0004)

Objective: Insulin promotes glucose uptake, lipogenesis, cell proliferation and cell growth mainly via Akt phosphorylation. FoxO1 is a substrate of Akt, which is inactivated when phosphorylated by Akt. Via this mechanism, FoxO1 antagonizes insulin. On the other hand, constitutive activation of FoxO1 reportedly enhances Akt phosphorylation. Thus, FoxO1 activation, via Akt phosphorylation, may mimic the functions of insulin. Methods: We overexpressed constitutively-active FoxO1 (CA-FoxO1) and FoxO1Δ256, a dominant-negative mutant, in 3T3-L1 adipocytes by adenoviruses and investigated the effects of these proteins on insulin’s functions. Results: CA-FoxO1 enhanced Akt phosphorylation, glucose uptake (275%, P Conclusion: Activation of FoxO1 selectively mimics the metabolic functions of insulin, without its proliferative effects. Contrary to previously reported results, FoxO1Δ256 does not always exert a dominant negative action. Disclosure T. Ohno: None. H. Ono: None. K. Takeda: None. K. Yokote: None.

Objective: FoxO1 is a substrate of serine/threonine-kinase Akt. Although FoxO1 is phosphorylated by Akt and inactivated by insulin stimulation, constitutive activation of FoxO1 is reported to enhance Akt phosphorylation. Therefore, constitutive activation of FoxO1 may mimic insulin’s functions via Akt phosphorylation. Methods: Constitutively-active FoxO1 (CA-FoxO1) in 3T3-L1 adipocytes is overexpressed by adenovirus and Changes in insulin signaling and downstream actions was studied. Results: CA-FoxO1 induced Akt phosphorylation in differentiated 3T3-L1 adipocytes. Regarding downstream actions, CA-FoxO1 significantly enhanced glucose uptake (148.6% compared to controls, P =0.030), GLUT4 translocation (297.6%, P Conclusion: Constitutive activation of FoxO1 induced Akt phosphorylation even in differentiated 3T3-L1 adipocytes, but FoxO1 activation mimicked only metabolic functions of glucose but not proliferative or oncogenic functions of insulin. This selective mimicking of insulin by FoxO1 activation in adipocytes may improve glucose metabolism with a low risk of tumorigenesis. The mechanisms of FoxO1-Akt feedback is suggested not to be the increase in IR-β or p110α subunit of PI 3-kinase as previously reported, but to be mainly downstream of PI 3-kinase. Disclosure T. Ohno: None. H. Ono: None. K. Yokote: Research Support; Self; Astellas Pharma Inc., Daiichi Sankyo, Eli Lilly Japan K.K., Kowa Company, Ltd., Kyowa Hakko Kirin Co., Ltd., Merck Sharp & Dohme Corp., Mitsubishi Tanabe Pharma Corporation, Mochida Pharmaceutical Co., Ltd., Nippon Boehringer Ingelheim Co. Ltd., Novartis Pharma K.K., Novo Nordisk Inc., Ono Pharmaceutical Co., Ltd., Pfizer Japan Inc., Sanofi K.K., Shionogi & Co., Ltd., Sumitomo Dainippon Pharma Co., Ltd., Taisho Pharmaceutical Co., Ltd., Takeda Pharmaceutical Company Limited, Teijin Pharma Limited. Speaker’s Bureau; Self; Abbott, Astellas Amgen, AstraZeneca K.K., Bayer Inc., FUJIFILM Pharmaceuticals U.S.A., Inc., Kaken Pharmaceutical Co., Ltd., Sanwa Kagaku Kenkyusho.