Dai, E. Y. | bioRxiv Science

bioRxiv2026

Metabolic Reprogramming Induced by Mitochondrial Citrate Carrier Deletion Mitigates Antibiotics-Induced Acute Tubular Injury

IntroductionThe mitochondrial citrate carrier (CiC), which mediates the transport of citrate across mitochondria, has been implicated in various diseases, but its role in kidney tubules is unclear. Here, we unraveled a novel role of CiC in tubular metabolism in the context of antibiotics-induced acute tubular injury (ATI). MethodsATI was induced by administration of vancomycin and gentamycin for 48 hours in mice (V+G-ATI). Tubular-specific CiC knockout (KO) was induced by adeno-associated virus (AAV) serotype 9 encoding Cre recombinase driven by KSP promoter (AAV9-Ksp-Cre) injection. Unbiased proteomic and metabolomic analyses were performed in CiC KO mouse kidneys. We performed in vivo 13C metabolic flux analysis to elucidate metabolic alterations in ATI and the effect of CiC KO. ResultsIn this study, V+G-induced ferroptosis, oxidative damage, and extensive ATI in mice were alleviated by CiC KO. Metabolic reprogramming induced by CiC KO increased mitochondrial TCA cycle intermediates, including alpha ketoglutarate (AKG), and elevated levels of the endogenous antioxidant glutathione (GSH). Supplementation with AKG or GSH attenuated V+G-ATI in mice. Tracking of the 13C pyruvate / lactate revealed an increased flux of glucose oxidation pathway in V+G-ATI. Interestingly, tubular-specific CiC KO expands the effective TCA cycle pool reserve space, which may contribute to mitigation of ROS. The beneficial metabolic alteration in CiC KO requires AKG and glutamate, as simultaneous inhibition of mitochondrial transporters of AKG and glutamate attenuated the cytoprotective effects of CiC KO against antibiotic-induced oxidative damage. ConclusionsThis is the first study to demonstrate the role of mitochondrial CiC in kidney tubular epithelial cells, showing that it induces metabolic alterations that protect against antibiotic-induced ATI.

pathology↗

bioRxiv2025

Endothelial cell Pannexin1 overexpression impairs ischemic stroke outcome in a sex-dependent manner

Ischemic stroke is a leading cause of morbidity and mortality. We have previously shown that deletion of endothelial cell (EC) Panx1 reduces ischemic stroke infarct volume and reduces cerebral arterial myogenic reactivity, which regulates cerebral blood flow. We hypothesized that EC Panx1 content dictates ischemic stroke outcome and thus increased EC Panx1 expression will worsen ischemic stroke outcomes due to exacerbated myogenic tone development and impaired cerebral blood flow recovery. To test this, we generated the Cdh5-CreERT2+ ROSA26-hPanx1Tg mouse model that conditionally overexpresses the human isoform of Panx1 specifically in EC. We have found that cerebral myogenic reactivity is significantly increased with overexpression of EC Panx1 only in female mice, without alterations in peripheral vascular reactivity or blood pressure regulation. Similarly, we found that infarct size was increased and recovery of cerebral blood flow was reduced in female but not male EC Panx1 overexpressing mice. Our findings indicate a role for EC Panx1 as a mediator of ischemic stroke recovery. Furthermore, these data suggest a potential sex-dependent effect for EC Panx1, where females are more sensitive to increased EC Panx1 in cerebral vascular function and may provide a potential therapeutic target for the treatment of ischemic stroke in women.

physiology↗