Abstract
Rationale: Obesity-associated metabolic diseases such as metabolic dysfunction-associated steatotic liver disease (MASLD) and type 2 diabetes mellitus (T2DM) are increasing rapidly, necessitating physiologically relevant in vitro models of the liver-pancreas axis. While recent multi-organoid systems have advanced inter-organ modeling, many systems still fall short of replicating the complex and directional metabolic interactions required to accurately reflect disease progression. This is partly due to inherent limitations such as reliance on passive diffusion for metabolic exchange and the use of shared or non-compartmentalized media, which restrict tissue-specific functions and fail to mimic in vivo-like physiological gradients. Methods: To overcome these limitations, we developed a multi-organoid device (MOD) that incorporates convective flow and physically separates liver and pancreatic organoids in distinct media environments. To evaluate the effectiveness of this co-culture system, we assessed metabolic transport using FITC-dextran and examined pancreatic and liver organoid function by measuring insulin and albumin secretion respectively. The effectiveness of the MOD in modeling MASLD-induced T2DM was further validated through functional assays and transcriptomic analysis. Results: The MOD successfully recapitulated key pathological features of MASLD-induced T2DM. Convective flow significantly enhanced directional transport of glucose and other metabolic molecules compared to passive diffusion, as validated by simulation and diffusion assays. Media separation preserved organoid function, increasing insulin and albumin secretion by 1.8- and 1.6-fold, respectively, compared with the non-separated group. Importantly, the device achieved rapid glucose regulation following glucose stimulation, with normoglycemia restored within 2 hours closely mimicking physiological glucose regulation not previously attainable in existing systems. Under MASLD conditions, the platform further revealed that liver-derived Fetuin-A was associated with β-cell apoptosis in pancreatic organoids. Conclusion: This MOD effectively models the pathophysiological cascade linking MASLD and T2DM by integrating organ-specific environments, convective flow, and multi-organ crosstalk. It offers a robust and biologically relevant tool for mechanistic studies of metabolic diseases and provides a promising platform for preclinical drug screening and therapeutic development.