Harnessing anti-TNFR1 therapy has a limited impact on inflammation and motor function after stroke in obese male mice

Obesity is a significant global health concern that exacerbates the risk and severity of ischemic stroke through chronic low-grade systemic inflammation and metabolic dysregulation. Tumor necrosis factor (TNF) signaling, particularly through its TNF receptor 1 (TNFR1), is involved in obesity-driven inflammation and adverse stroke outcomes. To assess the potential of TNFR1 blockade as a treatment strategy, we employed a diet-induced obesity model of ischemic stroke. Male C57BL/6 mice were fed a regular diet or high-fat diet for 6 weeks prior to stroke induction via photothrombosis and treated with either a TNFR1-neutralizing antibody or isotype control antibody. Outcomes were evaluated using motor function assessments, systemic inflammatory biomarker measurements, and brain tissue analysis, including evaluation of microglia, astrocytes, oligodendrocytes, myelin integrity, and stroke size. Results showed that obese mice exhibited worsened motor deficits and heightened systemic inflammation following stroke compared to non-obese controls. Treatment with anti-TNFR1 antibody did not ameliorate the increased functional deficits but did improve interleukin-6 cytokines levels after stroke in obese mice, while it had no effects on non-obese controls. Moreover, anti-TNFR1 therapy did not impact infarct size, microglial and astrocyte reactivity, or myelin integrity in both dietary groups. Overall, TNFR1-targeted therapy had a limited impact on obesity-exacerbated stroke outcomes, suggesting the need to explore broader or combination immunomodulatory approaches. These findings also emphasize the importance of considering comorbidities such as obesity in stroke, as they can influence both disease progression and treatment effectiveness.