Rutin hydrate relieves neuroinflammation in zebrafish models: Involvement of NF-κB pathway as a central network

Neuroinflammation is prevalent in multiple brain diseases and may also lead to dementia, cognitive impairment, and impaired spatial memory function associated with neurodegenerative diseases. A neuroprotective and antioxidant flavonoid, rutin hydrate (RH), was evaluated for the anti-neuroinflammatory activity mediated by copper sulfate (CuSO₄) solution and lipopolysaccharide (LPS) in zebrafish. The results showed that 100 mg/L RH significantly reduced the ratio of neutrophil mobility in caudal hematopoietic tissue (CHT) region caused by CuSO₄ and the number of neutrophils co-localized with facial peripheral nerves. In the LPS model, RH co-injection significantly diminished neutrophil and macrophage migration. Therefore, RH exhibited a significant rescue effect on both models. In addition, RH treatment remarkably reduced the effects of neuroinflammation on the locomotor ability, expression levels of genes associated with behavioral disorders, and acetylcholinesterase (AChE) activity. Furthermore, network pharmacology techniques were employed to investigate the potential mechanisms, and the associated genes and enzyme activities were validated in order to elucidate the underlying mechanisms. Network pharmacological analysis and zebrafish model indicated that RH regulated the expressions of NF-κB pathway-related targets (Toll-like receptor 9 (tlr9), nuclear factor kappa B subunit 1 (nfkb1), RELA proto-oncogene (RelA), nitric oxide synthase 2a, inducible (nos2a), tumour necrosis factor alpha-like (tnfα), interleukin 6 (il6), interleukin 1β (il1β), chemokine 8 (cxcl8), and macrophage migration inhibitory factor (mif)) as well as six key factors (arachidonic acid 4 alpha-lipoxygenase (alox4a), arachidonate 5-lipoxygenase a (alox5), prion protein a (prnpa), integrin, beta 2 (itgb2), catalase (CAT), and alkaline phosphatase (ALP) enzymes). Through this study, a thorough understanding of the mechanism underlying the therapeutic effects of RH in neuroinflammation has been achieved, thereby establishing a solid foundation for further research on the potential therapeutic applications of RH in neuroinflammatory disorders.