Prag, H. | bioRxiv Science

bioRxiv2025

Immunomodulation by AZD1656 reverses cardiac dysfunction, metabolic remodelling and reduces infarct size in type 2 diabetic cardiomyopathy

Type 2 diabetes (T2D) precipitates diabetic cardiomyopathy (dbCM), a condition characterized by chronic inflammation, metabolic dysregulation and impaired cardiac performance. Here we show that the glucokinase activator AZD1656, originally developed for glycaemic control but later identified to have immunomodulatory effects, reverses cardiac dysfunction and metabolic remodelling in dbCM. In obese, hyperglycaemic db/db mice with diastolic dysfunction, six weeks of AZD1656 treatment improved myocardial performance, reduced infarct size and enhanced post-ischaemic recovery. Integrated metabolic, functional and histological analyses revealed restoration of mitochondrial metabolism and attenuation of fibrosis. Mechanistically, AZD1656 remodelled the cardiac immune landscape by promoting regulatory T-cell infiltration. These findings demonstrate a link between cardiac inflammation and metabolic remodelling in dbCM and highlight that modulation of immune cells and metabolism can protect the diabetic heart. Targeting immunometabolic pathways may therefore offer a therapeutic strategy to alleviate cardiac dysfunction and reduce infarct vulnerability in T2D

physiology↗

bioRxiv2023

Activation of the Keap1/Nrf2 pathway suppresses mitochondrial dysfunction in C9orf72 ALS/FTD in vivo models and patient iNeurons

Mitochondrial dysfunction such as excess production of reactive oxygen species (ROS) and defective mitochondrial dynamics are common features of C9orf72 Amyotrophic Lateral Sclerosis/Frontotemporal Dementia (ALS/FTD), but it remains unclear whether these are causative or a consequence of the pathogenic process. To address this, we have performed a comprehensive characterisation of mitochondrial dysfunction in vivo model, analysing multiple transgenic Drosophila models of C9orf72-related pathology, which can be correlated to disease-relevant locomotor deficits. Genetic manipulations to reverse different aspects of mitochondrial disruption revealed that only genetic upregulation of antioxidants such as mitochondrial Sod2 and catalase were able to rescue C9orf72 locomotor deficits, suggesting a causative link between mitochondrial dysfunction, ROS and behavioural phenotypes. By analysing the Keap1/Nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, a central antioxidant response pathway, we observed a blunted response in the C9orf72 models. However, both genetic reduction of Keap1 and its pharmacological targeting by dimethyl fumarate (DMF), was able to rescue C9orf72-related motor deficits. In addition, analysis of C9orf72 patient-derived iNeurons showed increased ROS that was suppressed by DMF treatment. These results indicate that mitochondrial oxidative stress is an upstream pathogenic mechanism leading to downstream mitochondrial dysfunction such as alterations in mitochondrial function and turnover. Consequently, our data support targeting the Keap1/Nrf2 signalling pathway as a viable therapeutic strategy for C9orf72-related ALS/FTD.

neuroscience↗