Therapeutic hypothermia (TH) is a promising
neuroprotective agent for treating
stroke. However, its clinical application was limited by the impractical duration.
Icariin (ICA) were reported to have
therapeutic effect on
cerebral ischemia. In this research, our aim was to investigate whether the combination of TH and ICA had better
neuroprotective effects on
ischemic stroke. An
ischemia-reperfusion rat model was established and treated with mild
hypothermia, ICA or
JSH-23 (inhibitor of NF-κB). Thermistor probe, 2'3'5'-triphenyl tetrazolium
chloride (TTC), 5/12-score system, and ELISA were used to detect temperature (rectum, cortex, striatum),
infarct volume, neurological deficit, and cerebral cell death of these rats. The expressions of
tumor necrosis factor (TNF)-α,
Interleukin- 6 (IL-6),
nuclear factor-kappa B (NF-κB), nuclear factor erythroid2-related factor (Nrf2),
peroxisome proliferator activated receptor gamma (PPARα), PPARγ,
Janus kinase 2 (JAK2), p-JAK2, signal transducers and activators of transduction-3 (STAT3), and p-STAT3 were detected by Western blot or q-PCR. Mild
hypothermia, ICA, and
JSH-23 reduced the
cerebral infarct volume, neurological deficit, cerebral cell death of rats, downregulated the expressions of TNF-α,
IL-6, C-
Caspase 3 and Bax, and the activation of PPARs/Nrf2/NF-κB and JAK2/STAT3 pathways, but elevated the expression of Bcl-2. ICA promoted the effect of mild
hypothermia on
infarct volume, neurological deficit, and cerebral cell death. Moreover, ICA also enhanced the regulatory effect of mild
hypothermia on apoptosis/
inflammation factors expressions and activation of PPARs/Nrf2/NF-κB and JAK2/STAT3 pathways. ICA could promote
mild hypothermia-induced neuroprotection by inhibiting the activation of NF-κB through the PPARs/Nrf2/NF-κB and JAK2/STAT3/NF-κB pathways in experimental
stroke.