Interplay between Hyperglycemia and Chikungunya Virus Infection: Pathophysiological Insights from Murine Model

Abstract

Chikungunya fever (CHIKF) is a re-emerging viral disease characterized by acute systemic manifestations and debilitating musculoskeletal symptoms that can persist after viral clearance. Although typically self-limiting in healthy individuals, clinical outcomes are significantly worsened in patients with pre-existing comorbidities, particularly diabetes mellitus (DM). Epidemiological data links DM to heightened CHIKF severity and a greater risk of developing chronic arthropathy, yet the mechanism underpinning this association remains poorly understood. In this study, we established an in vivo streptozotocin (STZ)-induced diabetic C57BL/6 mice as a model to investigate the impact of DM on CHIKV pathogenesis. STZ induces selective pancreatic {beta}-cell destruction and persistent hyperglycemia. Diabetic animals infected with CHIKV exhibited aggravated joint inflammation, increased nociceptive sensitivity, and elevated serum markers of muscle and hepatic injury, including creatine kinase (CK) and alanine aminotransferase (ALT). Histopathological analyses revealed that CHIKV infection alone disrupted joint architecture. However, in the diabetic context, these alterations were significantly exacerbated, with enhanced inflammatory infiltrates, chondrocyte loss, osteocyte necrosis, and fibrotic remodeling. These results demonstrate that the diabetic metabolic environment profoundly amplifies CHIKV-induced tissue damage and impairs resolution of inflammation, offering a plausible mechanistic explanation for the poorest CHIKF outcomes observed in diabetic patients. Thus, this model provides a valuable platform for exploring the molecular drivers of CHIKF severity and chronicity, especially among DM patients, as well as for development of pharmacological tools to mitigate CHIKV-associated complications in metabolically vulnerable populations. ImportanceChikungunya virus is responsible for a re-emerging disease that causes intense joint pain and long-lasting inflammation, especially in vulnerable individuals. People with diabetes are known to suffer more severe and persistent symptoms, but the biological reasons behind this have remained unclear. In this study, we used a diabetic mouse model to investigate how a high-glucose environment influences the course of Chikungunya virus infection. We found that diabetic mice experienced more intense joint damage, increased pain sensitivity, and signs of broader organ injury compared to non-diabetic animals. Microscopic analyses of tissues showed greater inflammation and structural damage in the joints of diabetic animals. These findings suggest that diabetes directly worsens the effects of Chikungunya virus infection by amplifying inflammation and delaying healing. This model helps explain why diabetic patients have worse outcomes and may assist in developing new treatments to protect high-risk populations from long-term complications of this infection.