New Dimensions in Diabetic Kidney Disease Research: Advanced Organoids and Organs-on-a-Chip.

Diabetic kidney disease has increasingly emerged as a global public health concern, yet substantial challenges persist in its mechanistic research and drug development. Traditional 2-dimensional cell cultures and animal models frequently lack the capacity to faithfully recapitulate human pathophysiological conditions, and the use of animal models is increasingly limited by ethical and policy-related hurdles. In vitro models such as organoids and organs-on-a-chip have demonstrated remarkable advantages, enabling more faithful simulation of the in vivo microenvironment. The advancement of 3-dimensional bioprinting, microfluidic, and vascularization technologies has further propelled the maturation and progress of in vitro kidney models. This review summarizes and discusses in vitro kidney models and their advances, including kidney cell lines, spheroids, kidney organoids, and kidneys-on-a-chip. It also elaborates on the establishment of diabetic kidney disease models based on these in vitro platforms, which provides robust support for both basic and clinical research.