Green Tea with EGCG Active Compound Decreases NLRC3 Expression in Middle Cerebral Artery Occlusion (MCAO) Rats Model

Stroke ranks among the leading global causes of mortality and disability. During an ischemic stroke, there is an increase in oxidative stress. When oxidative stress occurs, mTOR is activated, causing an increase in NLRP3 expression. Nucleotide-binding oligomerization domain-containing 3 (NOD3) (as known as NLRC3) exerts an inhibitory effect on NLRP3, specifically inhibiting the pyroptosis process in microglial cells. Additionally, NOD3 serves as an inhibitor of the mTOR pathway. Inhibition of mTOR can result in the downregulation of the NOD3 protein. Green tea (Camellia sinensis) has been correlated to neuroprotection, especially the active compound Epigallocatechin-3-gallate (EGCG), which has an antioxidant effect. In the microglia cell of the Rattus norvegicus middle cerebral artery occlusion (MCAO) model, this study aims to ascertain the changes in nucleotide-binding oligomerization domain containing 3 (NOD3) expression with the intervention of green tea, containing the active compound EGCG. Eleven male rats were randomly assigned to each of the six groups. The groups are sham = healthy-rats group, P0 = control group (MCAO), P1 = MCAO with EGCG 10mg/kg Body Weight treatment, P2 = MCAO with EGCG 20mg/kg BW Body Weight treatment, P3 = MCAO with EGCG 30mg/kg Body Weight treatment, and P4 = MCAO with green tea extract 'Meditea' 30mg/kg Body Weight treatment. The stroke condition was created using the MCAO model by locking the internal carotid artery with a bulldog clamp for 180 minutes. For seven days, the intervention was administered once daily. The coronal portion of the infarcted hemisphere brain tissue was then removed for immunohistochemical analysis. The Allerd score represented the number of NOD3 expressions. NOD3 expression is downregulated in response to EGCG and green tea extract intervention. The 10mg/kg Body Weight treatment resulted in a significant difference in NOD3 expression (p = 0.001). Green tea's active components, EGCG and NOD3, have a correlation (r = -0.330; p = 0.007). Conclusions: Green tea may treat ischemic stroke because its active compound, EGCG, decreases NOD3 expression.