73 The extremely exciting aspect of this zebrafish-centered research was the finding that m4PTB treatment was beneficial to mice with AKI from ischemia.73 Mice with moderate IRI that were given m4PTB had accelerated recovery, and mice with severe IRI showed reduced interstitial fibrosis.73 The researchers found that m4PTB treatment was associated with elevated cell cycling in tubular cells and a decrease of cells in G2/M arrest.73 These results indicate that there are fundamental similarities in the response to AKI from chemical toxins between the zebrafish and mammalian kidney.73 and 85 Thus, these data strongly suggest
Thiazovivin cell line the practicality of using zebrafish as a simplified screening tool for drug discovery that can be relevant to mammals, but would at present be prohibitive for many labs working with mammalian models. In addition,
another promising injury model for future studies is laser ablation injury. While gentamicin-injury in the zebrafish embryo is lethal, selleck products focal tubule injury to a single nephron is typically not lethal.69 Further, there is some evidence for tubular regeneration based on observations of gross cellular replacement that were documented following laser ablation injury of pronephros cells in the zebrafish embryo (Fig 6).69 Laser ablation could potentially serve as a highly controlled in vivo model of AKI, as this protocol allows the induction of cell death in focal areas within the kidney O-methylated flavonoid tubule. Substantial work needs to be done to characterize this damage model. One intriguing potential with this approach is that different populations of cells throughout the nephron can be targeted, allowing analysis of injury and regeneration mechanisms in discrete nephron segment populations. As previously mentioned, the embryonic zebrafish pronephros develops into the adult kidney known as the mesonephros.4, 5 and 6 The adult zebrafish mesonephric
kidney is a single, flattened structure that is adherent to the dorsal body wall via connective tissues (Fig 1, C). 86 Anatomically, the kidney consists of 3 main parts: the head, the trunk or so-called saddle, and the tail. Nephrons in the mesonephros are similar to those found in the embryonic kidney; however, the adult kidney nephrons are highly bifurcated and are drained by 2 collecting ducts ( Fig 1, C’). 10, 70 and 71 As the zebrafish ages, new nephrons are continually added to the kidney, and arise from renal progenitors that are thought to be interspersed among the interstitial stroma located between nephrons. 70 and 71 This process of neonephrogenesis shares molecular hallmarks with the neonephrogenesis induced after renal injury (discussed in more detail below). Utilizing the adult zebrafish in experimental studies is beneficial because it enables the examination of hundreds of nephrons (approximately 300–500 depending on the age of the adult fish) compared with the 2 nephrons found in embryos.