Kobe University · University Hospital

Research keywordsFabry disease・enzyme replacement therapy・SGLT2 inhibitors・Lyso-Gb3 biomarkers・immune-mediated nephrotic syndrome・cardiorenal protection・calcimimetic therapy

This is a public-data preview. Personalized fit, contact angles, and saved workflows require sign-in.

• Investigation of bone mineral density and the changes by enzyme replacement therapy in patients with Fabry disease.2008 · BACKGROUND: Fabry disease (FD) is an inherited disorder that causes organ dysfunction. However, only a few studies have reported on bone mineral density (BMD) in FD patients, and the relationship between BMD and clinical factors such as globotriaosylsphingosine (lyso-Gb3) remains unclear. Therefore, the current study sought to investigate BMD in FD patients, the relationship between BMD and lyso-Gb3, and the effects of enzyme replacement therapy (ERT) on changes in BMD and lyso-Gb3. METHODS: This single-center, observational study included 15 patients who visited our facility for FD between January 2008 and June 2021. We assessed BMD and clinical characteristics in study patients, including plasma lyso-Gb3 levels, and examined the relationship between BMD and plasma lyso-Gb3 levels, and changes in BMD after starting ERT. RESULTS: Male patients' BMD had reduced, whereas female patients' BMD was preserved. Male patients had significantly higher plasma lyso-Gb3 levels than female patients. Moreover, plasma lyso-Gb3 levels were found to be significantly related to the lumbar spine and femoral BMD. These were strongly linked with plasma lyso-Gb3 levels in male patients, whereas no strong link was observed in female patients. Furthermore, BMD significantly increased only in male patients although plasma lyso-Gb3 levels significantly decreased by ERT in all patients. CONCLUSION: BMD decreased possibly due to Gb3 accumulation, and ERT could increase BMD in male FD patients.
• Renoprotective effects of SGLT2 inhibitors in patients with Fabry disease.BACKGROUND: Fabry disease (FD) is a rare X-linked lysosomal storage disorder characterized by globotriaosylceramide (Gb3) accumulation, resulting in kidney and cardiac dysfunction. Although enzyme replacement therapy (ERT) and chaperone therapy are the standard therapies, progression of renal decline persists. Sodium-glucose co-transporter 2 (SGLT2) inhibitors exert renoprotective effects in chronic kidney disease (CKD), but their efficacy in FD remains unknown. METHODS: We retrospectively analyzed data of 10 patients with FD treated with SGLT2 inhibitors and compared their renal outcomes to 18 patients with CKD without FD. The estimated glomerular filtration rate (eGFR) slope, urinary albumin-to-creatinine ratio (UACR), and plasma brain natriuretic peptide (BNP) levels were assessed 1 year before and after initiating SGLT2 inhibitor therapy. Linear mixed-effects models were employed for statistical analysis. RESULTS: In patients with FD, the annual eGFR decline significantly improved from -4.38 mL/min/1.73 m2/year (IQR: -10.57 to 0.59) before treatment to 1.25 (IQR: -4.16 to 9.74) after treatment (p
• The calcimimetic etelcalcetide attenuates pressure overload-induced cardiac hypertrophy in rats with and without chronic kidney disease.INTRODUCTION: Calcimimetics such as etelcalcetide (ET) are used to manage secondary hyperparathyroidism patients with chronic kidney disease (CKD) on dialysis. While their cardiovascular benefits-including left ventricular hypertrophy (LVH) suppression-are recognized, the underlying mechanisms remain unclear. This study investigated how ET suppresses LVH using rat models. METHODS: LVH was induced via transverse aortic coarctation, and CKD by 5/6 nephrectomy. Rats were assigned to the sham, CKD, LVH, or CKD/LVH groups, with each pathological group further divided into vehicle- or ET-treated subgroups. After eight weeks of treatment, echocardiography, histological, biochemical, and molecular analyses were conducted. RESULTS: ET reduced serum parathyroid hormone and fibroblast growth factor 23 (FGF23) levels in the CKD and CKD/LVH groups but not in the LVH group, where these levels were not increased. ET did not affect serum calcium, phosphorus, or vitamin D levels in the LVH and CKD/LVH groups. Nonetheless, ET suppressed cardiac hypertrophy and cardiomyocyte enlargement in the LVH and CKD/LVH groups despite no changes in systemic mineral metabolism parameters. Mechanistically, ET attenuated cardiac hypertrophy, serum aldosterone levels, and cardiac renin-angiotensin-aldosterone system (RAAS) components in the LVH and CKD/LVH groups. Cardiac FGF23 expression, elevated in the LVH and CKD/LVH groups, was also decreased by ET. The calcineurin/nuclear factor of the activated T-cell signaling pathway was unaffected. CONCLUSION: ET effectively suppressed LVH in the LVH and CKD/LVH groups. These findings suggest that ET's cardioprotective effects are mediated via the modulation of the RAAS and cardiac FGF23 expression rather than solely through the correction of CKD-mineral bone disorder abnormalities.
• Co-localization of IgG with nephrin in immune-mediated idiopathic nephrotic syndrome.BACKGROUND: Increased serum anti-nephrin antibody titers and co-localization of nephrin and IgG in kidney tissues have been reported in minimal change disease (MCD) and post-transplant recurrent focal segmental glomerulosclerosis (FSGS). These results indicate an association of anti-nephrin antibodies with nephrotic syndrome (NS); however, the exact relationship remains unclear. Herein, we evaluated nephrin/IgG co-localization in the glomeruli of patients with various kidney diseases, including monogenic NS, to clarify the association between idiopathic nephrotic syndrome (INS) and anti-nephrin antibodies. METHODS: IgG and nephrin co-localization was investigated in 52 kidney tissue biopsy samples, comprising INS in the active phase (n = 26; MCD, n = 19; FSGS, n = 7) and remission (n = 6), monogenic NS (n = 3), and other kidney diseases (n = 17). Double-immunofluorescence staining for nephrin/IgG was performed in unfixed frozen sections for 2 h at room temperature with Alexa Fluor-labeled nephrin/IgG cocktail antibodies. Nephrin/IgG co-localization was assessed using optical sectioning under a fluorescence microscope. RESULTS: Nephrin/IgG co-localization was observed in 81% (21/26, children: 15/17, adults: 6/9) of active INS cases, 84% (16/19) of MCD cases, and 71% (5/7) of FSGS cases. No co-localization was observed in NS with monogenic variants or other kidney diseases. CONCLUSION: Nephrin/IgG co-localization in the kidney tissue is finding observed in active INS, strongly indicating an association between anti-nephrin antibodies and INS onset. The nephrin/IgG cocktail antibody is a rapid and effective approach for investigating INS pathogenesis that facilitates the differential diagnosis of immune-mediated NS from other kidney diseases, including monogenic NS.

• Official profile