Department of Medical Sciences and Public Health, University of Cagliari, Electron Microscopy Laboratory, Division Pathological Anatomy, Cagliari, Italy.
Eur Rev Med Pharmacol Sci. 2022 May;26(9):3301-3309. doi: 10.26355/eurrev_202205_28749.
Acyl-CoA-binding protein (ACBP), also known as diazepam binding inhibitor (DBI), is a small phylogenetically conserved protein. This ancestral peptide is multifunctional, performing intracellular activities as ACBP protein or extracellular roles as DBI. Several studies showed its endless facets, including a relevant activity as appetite stimulator and as anabolic factor. High levels of ACBP have been described in erythrocytes, liver, kidney, and gut cells. The aim of this study was to analyze, at immunohistochemical level, the expression of ACBP in fetal human tissues during development, focusing on the developing kidney.
Immunohistochemistry for ACBP was performed on 30 human fetal kidneys, from 15 fetuses of gestational age ranging from 13 to 19 weeks. At autopsy, all kidney samples were 10% formalin-fixed, routinely processed and paraffin-embedded. Five micron-thick paraffin sections were stained with Hematoxylin and Eosin and PAS stain for a morphological examination.
ACBP was detected in all 30 kidneys analyzed in this study. No significant changes in ACBP expression were observed at different gestational ages. Immunostaining for ACBP was restricted to the epithelium covering the renal pelvis, the papillae, the collecting tubules, and the proximal and distal tubules. On the other hand, medullary regions and in the metanephric mesenchymal stem/progenitor cells did not show any reactivity for ACBP.
According to our findings, ACBP should be considered as a new player in the complex field of human nephrogenesis, given that it was detected in all fetal kidneys immunostained. Its preferential localization in the renal structures derived from the Wolf duct, such as pelvis epithelium and collecting ducts, suggests a major role for ACBP in the induction of the metanephric mesenchymal cells toward the differentiation into glomerular structures. ACBP expression in proximal and distal tubules, two structures originating from the metanephric mesenchyme, indicates a further role of this protein in nephron development. In conclusion, ACBP should be added to the multiple molecules involved in human nephrogenesis.
酰基辅酶 A 结合蛋白（ACBP），也称为地西泮结合抑制剂（DBI），是一种小的进化上保守的蛋白质。这种古老的肽具有多功能性，作为 ACBP 蛋白在细胞内发挥作用，或作为 DBI 在细胞外发挥作用。几项研究表明其具有无尽的方面，包括作为食欲刺激剂和合成代谢因子的相关活性。已经在红细胞、肝脏、肾脏和肠道细胞中描述了高水平的 ACBP。本研究的目的是在发育过程中分析免疫组织化学水平的 ACBP 在胎儿人体组织中的表达，重点是发育中的肾脏。
对来自 15 个妊娠年龄从 13 周到 19 周的胎儿的 30 个人类胎儿肾脏进行 ACBP 的免疫组织化学分析。尸检时，所有肾脏样本均用 10%福尔马林固定，常规处理并石蜡包埋。用苏木精和伊红染色和 PAS 染色对 5μm 厚的石蜡切片进行染色，以进行形态学检查。
在本研究分析的所有 30 个肾脏中均检测到 ACBP。在不同的妊娠年龄，ACBP 的表达没有明显变化。ACBP 的免疫染色仅限于覆盖肾盂、乳头、收集管以及近端和远端小管的上皮。另一方面，髓质区域和后肾间充质祖细胞没有任何针对 ACBP 的反应性。
根据我们的发现，ACBP 应该被认为是人类肾发生复杂领域的一个新参与者，因为它在所有免疫染色的胎儿肾脏中均被检测到。它在源自 Wolf 管的肾结构（如肾盂上皮和收集管）中的优先定位表明，ACBP 在诱导后肾间充质细胞向肾小球结构分化中起着主要作用。ACBP 在近端和远端小管中的表达，这两个结构起源于后肾间充质，表明该蛋白在肾单位发育中具有进一步的作用。总之，应该将 ACBP 添加到参与人类肾发生的多种分子中。
