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The diagnosis of insulinoma in perinatal women can be difficult, as hypoglycemic symptoms may be masked by pregnancy‐associated insulin resistance. In addition, when multiple insulinomas are observed, it is necessary to consider the possibility not only of MEN1, but also of insulinomatosis.

We investigated whether overnutrition during pregnancy were associated with the changes in gene expressions, oxygen metabolism, and vascular and hepatic parenchymal remodeling in fetal livers at mid gestational days E14.5 of dams fed a control diet (CD group) or a high-fat diet (HFD group) during pregnancy. Synchrotron-based phase-contrast micro-CT demonstrated embryos of HFD group showed hepatomegaly accompanied with the same size umbilical vein and less portal branching, which might result in liver hypoxia. Correspondingly, fetal livers of HFD group increased the expression of HIF-1alpha. To identify genes and pathways targeted by maternal overnutrition in fetal livers, we assayed mRNA levels with microarray. We identified 430 differentially expressed genes (DEGs) including 146 upregulated- and 284 downregulated genes in fetal livers of HFD group compared with those of CD group. The up-regulated DEGs were significantly enriched in DNA alkylation, bile secretion, and the down-regulated DEGs mainly enriched in neuronal system, cell maturation. Among upregulated DEGs, a cancer/testis antigen HORMAD1 was induced by hypoxia up to 30-fold compared with that in normoxia in primary mouse hepatocytes (PMH), and the genetic inhibition of HIF-1alpha by siRNAs abolished the stimulatory effect of hypoxia on Hormad1 expression. In addition, we found three putative hypoxia response elements within the mouse Hormad1gene. Interestingly, the tumor suppressor WW domain-containing oxidoreductase (WWOX), which inhibits the activity of HIF-1alpha, were remarkably decreased in hypoxia in PMH. Finally, HORMAD1 protein was upregulated in fetal livers and NASH-based HCC in offspring of HFD group at 15 weeks old. Our results suggest that WWOX-HIF-1alpha-HORMAD1 pathway might be involved in the development of NAFLD in offspring of obese and/or diabetic pregnant woman, and be an important therapeutic target of NASH/HCC. Disclosure T. Takiyama: None. Y. Takiyama: Other Relationship; Self; Gilead Sciences, Inc., Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Mochida Pharmaceutical Co., Ltd., Roche Diabetes Care, Taisho Pharmaceutical Co., Ltd. R. Bessho: None. H. Kitsunai: None. Y. Takeda: None. H. Sakagami: None. T. Sera: None. M. Nakamura: None. S. Horike: None. Y. Nishikawa: None.

Recent study has demonstrated the Nrf2 (NF-E2-related factor 2) activator bardoxolone methyl improved renal function in diabetic kidney disease (DKD). On the other hand, mitochondrial transcription factor A (TFAM) activation inhibits mitochondrial DNA (mtDNA) release into the cytoplasm and suppresses stimulator of interferon genes (STING)-mediated inflammation in renal proximal tubular cells. Sulforaphane (SFN), an isothiocyanate found in cruciferous vegetables, is recognized as activators of Nrf2. In this study, we investigated the effects of SFN on TFAM and STING expression and its mitochondrial protective and anti-inflammatory effects. Because mitochondrial damage caused by fatty acids bound to albumin is involved in pathogenesis of DKD due to increased albumin reabsorption, we treated human renal proximal tubular cells (Lonza) with palmitic acid (PA, 200µM). Total RNA, DNA and protein were extracted and analyzed by qRT-PCR and western blotting. To quantify the mitochondrial DNA released into the cytoplasm, DNA was extracted from cytoplasmic and nuclear fractions. SFN (10µM) induced Nrf2 downstream target gene, NAD(P)H:quinone oxidoreductase 1 (NQO-1) mRNA expression to 359% (p Disclosure R. Bessho: None. T. Takiyama: None. S. Promsuwan: None. H. Kitsunai: None. K. Sawamoto: Other Relationship; Self; Abbott, Boehringer Ingelheim Pharmaceuticals, Inc., Merck & Co., Inc., Ono Pharmaceutical Co., Ltd., Roche Diagnostics K. K., Taisho Pharmaceutical Co., Ltd. Y. Takeda: None. Y. Takiyama: Other Relationship; Self; Gilead Sciences, Inc., Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Mochida Pharmaceutical Co., Ltd., Roche Diabetes Care, Taisho Pharmaceutical Co., Ltd.

Nonalcoholic steatohepatitis (NASH), a progressive form of nonalcoholic fatty liver disease (NAFLD), is associated with hepatocellular carcinoma (HCC). The worldwide prevalence of NAFLD in children suggests an early-life origin. To examine the impact of intrauterine nutrition on the development of NASH/HCC, female C57BL/6J mice were fed with either high-fat diet (HFD) or control diet (CD) during gestation. After weaning, the male offspring were fed with CD, generating two groups of male offspring, HFD and CD. HFD remarkably elevated plasma NEFA and ALT. Consistently, HFD had severe form of NASH, presenting the fibrosis, accompanied with HCC. Synchrotron micro-CT showed the architectural remodeling of the parenchyma in HFD at 14.5 days postcoitum (dpc), one week and 15 weeks of age, not in CD. In the liver of HFD at 14.5dpc, gene ontology term enrichment analysis suggested that up-regulated differentially expressed genes (DEGs) significantly enriched in DNA alkylation, bile secretion, and the down-regulated DEGs mainly enriched in neuronal system, cell maturation. KEGG pathway analysis found down-regulated DEGs significantly enriched in five pathways including Graft-versus-host disease (LogP -24.785) such as FasL, and up-regulated HIF-1 signaling pathway in the liver of HFD at one week of age. On the contrary, 15-week-old HFD had increased cytoplasmic pimonidazole staining, but no nuclear staining of HIF-1α in HCC cells, which suggests breakdown of hypoxic response mechanism, concomitantly with up-regulated miR199a-5p, miR-1949, miR214-3p and miR-3090-5p, which target HIF-1α. This study demonstrates that the early exposure to an overnutrition in utero, subsequent neonatal and adult nutritional alternation cause NASH/HCC in offspring, accompanied by multiple changes in gene expressions. This means a “multi-hit theory.” Disclosure T. Takiyama: None. R. Bessho: None. K. Sawamoto: None. Y. Takiyama: Other Relationship; Self; Abbott, Boehringer Ingelheim Pharmaceuticals, Inc., Merck & Co., Inc., Ono Pharmaceutical Co., Ltd., Roche Diagnostics K.K., Taisho Pharmaceutical Co., Ltd.

Previous studies have demonstrated intrarenal hypoxia in patients with diabetes. Hypoxia-inducible factor (HIF)-1 plays an important role in hypoxia-induced tubulointerstitial fibrosis. Recent clinical trials have confirmed the renoprotective action of SGLT2 inhibitors in diabetic nephropathy. We explored the effects of an SGLT2 inhibitor, luseogliflozin on HIF-1α expression in human renal proximal tubular epithelial cells (HRPTECs). Luseogliflozin significantly inhibited hypoxia-induced HIF-1α protein expression in HRPTECs. In addition, luseogliflozin inhibited hypoxia-induced the expression of the HIF-1α target genes PAI-1, VEGF, GLUT1, HK2 and PKM. Although luseogliflozin increased phosphorylated-AMP-activated protein kinase α (p-AMPKα) levels, the AMPK activator AICAR did not changed hypoxia-induced HIF-1α expression. Luseogliflozin suppressed the oxygen consumption rate in HRPTECs, and subsequently decreased hypoxia-sensitive dye, pimonidazole staining under hypoxia, suggesting that luseogliflozin promoted the degradation of HIF-1α protein by redistribution of intracellular oxygen. To confirm the inhibitory effect of luseogliflozin on hypoxia-induced HIF-1α protein in vivo, we treated male diabetic db/db mice with luseogliflozin for 8 to 16 weeks. Luseogliflozin attenuated cortical tubular HIF-1α expression, tubular injury and interstitial fibronectin in db/db mice. Together, luseogliflozin inhibits hypoxia-induced HIF-1α accumulation by suppressing mitochondrial oxygen consumption. The SGLT2 inhibitors may protect diabetic kidneys by therapeutically targeting HIF-1α protein.

The glomerular number and size are major factors in predicting outcomes in renal disease. We have recently established synchrotron radiation microcomputed tomography (SRµCT) imaging of the glomeruli in perfused kidneys, and reported the glomerular and renal hypertrophy, but not glomerular loss in obese type 2 diabetic db/db mice. To visualize pathophysiological basis of diabetic kidney of type 1 diabetes, we here explored SRµCT imaging of the glomeruli in streptozotocin-induced type 1 diabetic male mice (STZ mice) and of control male C57BL/6J mice (control mice). STZ mice at the age of 22 weeks significantly showed hyperglycemia and elevated urinary albumin excretion, but not hypertension or body weight changes compared to control mice. There was approximately 22% loss of the total glomerular number (Nglom) of STZ mice compared to that of control mice (p Disclosure Y. Takiyama: None. T. Sera: None. M. Nakamura: None. R. Bessho: None. T. Takiyama: None. T. Ota: None. M. Haneda: None.

The renoprotective mechanism of SGLT2 inhibitors has not been fully elucidated. Tubular hypoxia is major driving force for proximal tubulopathy in diabetic kidney. In addition, diabetes causes dysregulation of AMP-activated protein kinase (AMPK) in kidney cortex. In this study, we assessed the effects of luseogliflozin, an SGLT2 inhibitor, on hypoxia inducible factor-1α (HIF-1α) expression and AMPK phosphorylation in cultured human renal proximal tubular epithelial cells (HRPTECs) and on tubulointerstitial pathological changes in diabetic mice. Luseogliflozin inhibited hypoxia (1%O2, 24h)-induced HIF-1α protein expression in HRPTECs in a dose-dependent manner (1-100µM). In addition, luseogliflozin increased AMPKα protein phosphorylation (Th172) in normoxic and hypoxic condition. Intriguingly, luseogliflozin suppressed oxygen consumption rate (OCR) measured by oxygen quenching phosphorescent probe by 69% in HRPTECs from normoxic condition. Hypoxia decreased OCR by 52% and luseogliflozin further decreased OCR by 33% from hypoxic condition. Moreover, luseogliflozin rescued hypoxic state in HRPTECs even under hypoxic conditions assessed by a hypoxia-sensitive dye, pimonidazole. These data indicate luseogliflozin inhibits HIF-1α expression through suppression of mitochondrial OCR, which leads to restore intracellular hypoxia. We next treated db/db mice with 15 mg/kg/day luseogliflozin for 8 weeks. Luseogliflozin ameliorated tubular injury compared to non-treated db/db mice. Furthermore, immunostaining of HIF-1α and fibronectin in cortical tubules revealed that luseogliflozin decreased HIF-1α and fibronectin expression in db/db mice. In conclusion, luseogliflozin decreases mitochondrial OCR and ameliorates tubular fibrosis at least partly by suppressing HIF-1α expression and activating AMPK in renal proximal tubules of diabetic mice. These results may provide a novel renoprotective target of SGLT2 inhibitor. Disclosure R. Bessho: None. Y. Takiyama: None. T. Takiyama: None. T. Ota: None.

Background Recent large-scale clinical studies demonstrate that sodium-glucose cotransporter 2 (SGLT2) inhibitors protect the diabetic kidney. However, clinical and animal studies have not shown the changes of the total glomeruli in the whole kidney treated with SGLT2 inhibitors. Methods We performed computed tomography (CT) imaging on mice using synchrotron radiation to investigate the impact of luseogliflozin, a SGLT2 inhibitor, on the number and volume of glomeruli in the whole kidney. Findings We did not observe a significant difference in the total glomerular number (Nglom) among mice. Luseogliflozin redistributed the number of glomeruli in different regions, accompanied by the normalization of diabetes-augmented renal volume (Vkidney). Diabetic db/db mice had a larger glomerular volume in the mid-cortex than did control db/m mice, and luseogliflozin increased the glomerular volume in all renal cortical zones of the whole kidney in db/db mice. According to the multivariate regression analysis, hemoglobin A1c level was the most relevant determinant of Vkidney, not Nglom or mean glomerular volume (Vglom), indicating that hyperglycemia induced renal (tubular) hypertrophy, but not glomerular enlargement. Luseogliflozin increased hypoxia in the juxtamedullary region, sustained upregulated renal renin expression and plasma renin activity, and failed to decrease albuminuria by downregulating megalin in db/db mice. Interpretation Based on our findings, SGLT2 inhibitors may alter glomerular distribution and size in addition to their glucose-lowering effects, presumably by affecting oxygen metabolism and humoral factors. Fund Funding for this research was provided by The Japan Society for the Promotion of Science , the Japan Diabetes Foundation, and Asahikawa Medical University .

To investigate the impact of diabetes and luseogliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor on the numbers and volumes of glomeruli in the whole kidneys, we performed CT imaging of diabetic db/db mice using synchrotron radiation at SPring-8. We found that there was no significant difference in the total glomerular number among mice. Diabetic mice had significantly larger glomerular volume in the mid-cortex compared to lean control db/m mice. Luseogliflozin reduced whole kidney volume, but not the glomerular hypertrophy in db/db mice. Luseogliflozin also decreased mesangial expansion and tubular damage in db/db mice. Luseogliflozin augmented hypoxia of S3 segment of proximal tubules in the juxtamedullary region and macula densa, as well as the number of intracellular vesicles in juxtaglomerular cells, and sustained upregulated renal renin expression in db/db mice. Luseogliflozin ameliorated hyperglycemia, glomerular and tubular injury, but not albuminuria. Db/db mice decreased the expression of renal megalin protein compared with that in db/m mice. Luseogliflozin-treated db/db mice also reduced the expression of megalin, accompanied with decreased reabsorbing urinary albumin as endocytotic ligand of megalin. In conclusion, our results suggest that oxygen metabolism and/or humoral factors more than blood glucose levels might determine the glomerular number and volume in diabetic kidney. Funding: This work was partially supported by a grant from the Japan Society for the Promotion of Science (JSPS KAKENHI grant no. 15K09372 to Y.T.), and by a Research Grant from the Japan Diabetes Foundation and Asahikawa Medical University (Research grant for Innovative Research in Life Science). Conflicts of Interests: Y.T. was also supported by several foundational grants, including grants from MSD, K.K., Eli Lilly and Company, Sanofi K.K., Takeda Pharmaceutical Co. and Taisho Pharmaceutical Co. No other potential conflicts of interest relevant to this article were reported. Ethical Approval Statement: These experiments were performed with the approval of the SPring-8 Proposal Review Committee (2012B1772, 2013A1655, 2013B1739).