Abnormal Cystatin C Levels in Two Patients with Bardet-Biedl Syndrome

Bardet-Biedl syndrome (BBS) is an autosomal recessive disorder characterized by central obesity, mental impairment, rod-cone dystrophy, polydactyly, hypogonadism in males, and renal abnormalities. The causative genes have been identified as BBS1-14. In the Western countries, the prevalence of this disease ranges from 1/13,500 to 1/160,000, while only a few Japanese patients have been reported in the English-language literature. The incidence of renal dysfunction or anomalies in previous reports varies considerably ranging from ∼20% to universal occurrence. We here report that two Japanese patients who had BBS with normal BUN and creatinine levels had elevated levels of cystatin C, a sensitive marker of glomerular filtration rate. A urine albumin level increased only in the elder patient. Thus, cystatin C may be useful for detecting renal abnormalities in patients with an apparent normal renal function. Because this disease is diagnosed by accumulation of symptoms, such a sensitive marker might help early diagnosis of BBS

Insulin-producing cells derived from ‘induced pluripotent stem cells’ of patients with fulminant type 1 diabetes: vulnerability to cytokine insults and increased expression of apoptosis-related genes

Aims/Introduction: The present study was carried out to generate induced pluripotent stem cells (iPSCs) from patients with fulminant type 1 diabetes, and evaluate the cytokine‐induced apoptotic reactions of β‐like insulin‐producing cells differentiated from the iPSCs.Materials and Methods: iPSCs were generated from fibroblasts of patients with fulminant type 1 diabetes by inducing six reprogramming factors. Insulin‐producing cells were differentiated from the iPSCs in vitro. The proportion of cleaved caspase‐3‐positive or terminal deoxynucleotidyl transferase 2′‐deoxyuridine, 5′‐triphosphate nick end labeling‐positive cells among insulin (INS)‐positive cells derived from fulminant type 1 diabetes iPSC and control human iPSC lines was evaluated under treatment with tumor necrosis factor‐α, interleukin‐1β and interferon‐γ. Ribonucleic acid sequencing was carried out to compare gene expressions in INS‐positive cells derived from fulminant type 1 diabetes iPSC and control human iPSC lines.Results: Two iPSC clones were established from each of three patients with fulminant type 1 diabetes. The differentiation of insulin‐producing cells from fulminant type 1 diabetes iPSC was confirmed by immunofluorescence analysis and KCl‐induced C‐peptide secretion. After treatment with pro‐inflammatory cytokines, these INS‐positive cells showed higher expression of cleaved caspase‐3 than those derived from control human iPSCs. Altered expression levels of several apoptosis‐related genes were observed in INS‐positive cells derived from the fulminant type 1 diabetes iPSCs by ribonucleic acid sequencing.Conclusions: We generated iPSCs from patients with fulminant type 1 diabetes and differentiated them into insulin‐producing cells. This in vitro disease model can be used to elucidate the disease mechanisms of fulminant type 1 diabetes

Examination of a Viral Infection Mimetic Model in Human iPS Cell-Derived Insulin-Producing Cells and the Anti-Apoptotic Effect of GLP-1 Analogue

<div><p>Aims</p><p>Viral infection is associated with pancreatic beta cell destruction in fulminant type 1 diabetes mellitus. The aim of this study was to investigate the acceleration and protective mechanisms of beta cell destruction by establishing a model of viral infection in pancreatic beta cells.</p><p>Methods</p><p>Polyinosinic:polycytidylic acid was transfected into MIN6 cells and insulin-producing cells differentiated from human induced pluripotent stem cells via small molecule applications. Gene expression was analyzed by real-time PCR, and apoptosis was evaluated by caspase-3 activity and TUNEL staining. The anti-apoptotic effect of Exendin-4 was also evaluated.</p><p>Results</p><p>Polyinosinic:polycytidylic acid transfection led to elevated expression of the genes encoding IFNα, IFNβ, CXCL10, Fas, viral receptors, and IFN-inducible antiviral effectors in MIN6 cells. Exendin-4 treatment suppressed the elevated gene expression levels and reduced polyinosinic:polycytidylic acid-induced apoptosis both in MIN6 cells and in insulin-producing cells from human induced pluripotent stem cells. Glucagon-like peptide-1 receptor, protein kinase A, and phosphatidylinositol-3 kinase inhibitors counteracted the anti-apoptotic effect of Exendin-4.</p><p>Conclusions</p><p>Polyinosinic:polycytidylic acid transfection can mimic viral infection, and Exendin-4 exerted an anti-apoptotic effect both in MIN6 and insulin-producing cells from human induced pluripotent stem cells.</p></div