Kidney international最新文献

Chronic kidney disease is one of the leading causes of mortality worldwide because of kidney failure and the associated challenges of its treatment including dialysis and kidney transplantation. About one-third of chronic kidney disease cases are linked to inherited monogenic factors, making them suitable for potential gene therapy interventions. However, the intricate anatomical structure of the kidney poses a challenge, limiting the effectiveness of targeted gene delivery to the renal system. In this review, we explore the progress made in the field of targeted gene therapy approaches and their implications for rare genetic kidney disorders, examining preclinical studies and prospects for clinical application. In vivo gene therapy is most commonly used for kidney-targeted gene delivery and involves administering viral and nonviral vectors through various routes such as systemic, renal vein, and renal arterial injections. Small nucleic acids have also been used in preclinical and clinical studies for treating certain kidney disorders. Unexpectedly, hematopoietic stem and progenitor cells have been used as an ex vivo gene therapy vehicle for kidney gene delivery, highlighting their ability to differentiate into macrophages within the kidney, forming tunneling nanotubes that can deliver genetic material and organelles to adjacent kidney cells, even across the basement membrane to target the proximal tubular cells. As gene therapy technologies continue to advance and our understanding of kidney biology deepens, there is hope for patients with genetic kidney disorders to eventually avoid kidney transplantation.

Altered polycystin-mediated endothelial flow mechanosensitivity contributes to the development of hypertension and cardiovascular complications in patients with autosomal dominant polycystic kidney disease (ADPKD). Stimulation of endothelial type 5 dopamine receptors (DR5) can acutely compensate for the endothelial consequences of polycystin deficiency, but the chronic impact of this approach must be evaluated in ADPKD. Nineteen patients with ADPKD on standard of care therapy were randomized to receive a 2-month treatment with the DR agonist rotigotine using transdermal patches, nine at 2 mg/24hours and ten at 4 mg/24hours or while ten were untreated. Rotigotine at the dose of 4 mg/24hours significantly increased nitric oxide release (nitrite levels from 10±30 to 46±34 nmol/L) and radial artery endothelium-dependent flow-mediated dilatation (from 16.4±6.3 to 22.5±7.3%) in response to hand skin heating. Systemic hemodynamics were not significantly modified but aplanation tonometry showed that rotigotine at 4 mg/24hours reduced aortic augmentation index and pulse pressure without affecting carotid-to femoral pulse wave velocity. Plasma creatinine and urea, urinary cyclic AMP, which contributes to cyst growth in ADPKD and copeptin, a surrogate marker of vasopressin, were not affected by rotigotine. In mice with a specific deletion of polycystin-1 in endothelial cells, chronic infusion of the peripheral DR5 agonist fenoldopam also improved mesenteric artery flow-mediated dilatation and reduced blood pressure. Thus, our study demonstrates that in patients with ADPKD, chronic administration of rotigotine improves conduit artery endothelial function through the restoration of flow-induced nitric oxide release as well as hemodynamics suggesting that endothelial DR5 activation may represent a promising pharmacological approach to prevent cardiovascular complications of ADPKD.

We recently reported the case of a patient who experienced three consecutive episodes of acute kidney injury, all of them following a "Brazilian" hair-straightening treatment. The cream used for the straightening procedure contained glyoxylic acid. To examine possible underlying mechanisms causing kidney injury, four groups of mice were exposed to topical application of (i) the straightening product, (ii) a cream containing 10% glyoxylic acid, (iii) a cream containing 10% glycolic acid or (iv) a control cream. Application of glycolic acid slightly increased urine oxalate excretion, while glyoxylic acid and the straightening product dramatically increased urine oxalate excretion and caused calcium oxalate nephropathy after transcutaneous absorption. Thus, glyoxylic acid was presumptively absorbed through the skin, metabolized to oxalate and promoted crystallization of calcium oxalate in urine. Hence, cosmetic products containing glyoxylic acid may induce acute kidney injury and should be discontinued. Further studies are needed to investigate the metabolism of glycolic acid and glyoxylic acid following topical application.

Apolipoprotein L1 (APOL1) variants G1 and G2 contribute to the excess risk of kidney disease in individuals of recent African ancestry. Since disease mechanisms and optimal treatments remain controversial, we study the effect of current standard-of-care drugs in mouse models of APOL1 kidney disease. Experiments were performed in APOL1 BAC-transgenic mice, which develop proteinuria and glomerulosclerosis following injection with a pCpG-free IFN-γ plasmid. Proteinuric, plasmid injected G1/G1 and G2/G2 mice were randomized to drug treatment or no treatment. Lisinopril, dapagliflozin, and hydralazine were administered in drinking water starting day seven. The urine albumin/creatinine ratio was measured twice weekly, and the kidneys examined histologically with the focal segmental glomerulosclerosis score computed from periodic acid-Shiff-stained sections. The angiotensin converting enzyme inhibitor lisinopril, at standard dose, reduced proteinuria by approximately 90-fold and reduced glomerulosclerosis in the APOL1 G1/G1 BAC-transgenic mice. These effects were independent of blood pressure. Dapagliflozin did not alter disease progression in either G1/G1 or G2/G2 mice. Proteinuria reduction and glomerulosclerosis in G2/G2 BAC-transgenic mice required lisinopril doses two times higher than were effective in G1/G1 mice but achieved a much smaller benefit. Therefore, in these BAC-transgenic mouse models of APOL1 disease, the anti-proteinuric and anti-glomerulosclerotic effects of standard dose lisinopril were markedly effective in G1/G1 compared with G2/G2 APOL1 mice. Comparable reduction in blood pressure by hydralazine treatment provided no such protection. Neither G1/G1 nor G2/G2 mice showed improvement with the sodium-glucose cotransporter-2 inhibition dapagliflozin. Thus, it remains to be determined if similar differences in ACE inhibitor responsiveness are observed in patients.