TLR4 and Cerebral ischemia: Meanwhile, polydatin treatment downregulated the expression of cerebral ischemia or spinal cord injury (SCI)-induced inflammatory mediators such as Toll-like receptor 4 (TLR4), NF-κB, cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), nitric oxide (NO), and ICAM-1 [48,49,50].