Department of Medicine, University of California San Diego, La Jolla, California, USA.
Veterans Affairs San Diego Healthcare System, San Diego, California, USA.
Nephron. 2023;147(12):774-777. doi: 10.1159/000531918. Epub 2023 Jul 25.
In acute kidney injury (AKI), proximal tubules are a primary site of injury, resulting in significant alterations in amino acid transport and metabolism. However, little is known about the therapeutic potential of targeting amino acid transporters. Here, we briefly review the first experimental evidence that targeting the sodium-coupled amino acid transporter SLC6A19 (B0AT1) can improve AKI outcome.
SLC6A19 is expressed in the small intestine and early proximal tubules, where it absorbs and reabsorbs most of the ingested and filtered neutral amino acids, respectively. Systemic SLC6A19 deficiency alleviates renal cellular senescence and suppresses subsequent inflammation and fibrosis in a murine model of aristolochic acid-induced nephropathy, which targets the proximal tubule. The underlying mechanisms remain to be determined, but potentially may include reduced tubular workload, an inhibitory effect on SGLT2, downstream shift in transport and preconditioning of late proximal tubules, and induction of a fasting-like phenotype and lowering tubular accumulation of branched-chain amino acids, which all can promote tubular health.
在急性肾损伤(AKI)中,近端小管是主要的损伤部位,导致氨基酸转运和代谢发生显著改变。然而,关于靶向氨基酸转运体的治疗潜力知之甚少。在这里,我们简要回顾了第一个实验证据,表明靶向钠偶联氨基酸转运体 SLC6A19(B0AT1)可以改善 AKI 结局。
SLC6A19 在小肠和早期近端小管中表达,分别吸收和重吸收大部分摄入的和滤过的中性氨基酸。系统性 SLC6A19 缺乏可减轻马兜铃酸诱导的肾病模型中肾脏细胞衰老,并抑制随后的炎症和纤维化,该模型靶向近端小管。潜在的机制尚待确定,但可能包括减少肾小管工作量、对 SGLT2 的抑制作用、转运的下游转移以及晚期近端小管的预适应,以及诱导类似禁食的表型和降低管状支链氨基酸的积累,所有这些都可以促进管状健康。