Oxidative Stress in Neurological Feline Infectious Peritonitis: Cerebrospinal Fluid 8-Hydroxy-2’-deoxyguanosine and Superoxide Dismutase Levels

Oxidative stress plays a key role in the pathogenesis of neurological disorders and viral infections affecting the central nervous system.8-Hydroxy-2'-deoxyguanosine (8-OHdG) is a marker of oxidative DNA damage, while superoxide dismutase (SOD) reflects antioxidant defense.This study aimed to evaluate SOD and 8-OHdG levels in the cerebrospinal fluid (CSF) of cats with neurological feline infectious peritonitis (FIP) to assess oxidative stress and antioxidant response.Twelve cats with neurological FIP and 10 age-matched control cats euthanized for non-neurological conditions were included.FIP diagnosis was confirmed by detecting feline coronavirus (FCoV) RNA in the CSF using real-time RT-PCR and by histopathological examination.CSF samples were analyzed for total protein, glucose, SOD, and 8-OHdG.Cats with FIP showed significantly higher CSF protein (740230 mg/dL) than controls (177 mg/dL).The CSF/serum glucose ratio was lower in FIP cats (0.390.18) than in controls (0.660.06).8-OHdG levels were elevated in FIP cats (6.88 ng/ml) compared to controls (1.09 ng/ ml; P<0.05).SOD levels were reduced in FIP cats (0.0340.026U/mg protein) versus controls (0.3120.136U/mg protein; P<0.001).These findings highlight a pronounced oxidative stress condition in neurological FIP, characterized by elevated 8-OHdG levels and reduced SOD concentrations in the CSF.This concurrent pattern may not only serve as a valuable biomarker of disease activity but also represent a potential therapeutic target for antioxidant-based strategies in affected cats.