Kuanxiong Aerosol Attenuates Ischemic Stroke Injury via Modulation of the TRPV1 ChannelOA

Objective:To evaluate the therapeutic effects of Kuanxiong Aerosol(KXA)on ischemic stroke with reperfusion and elucidate the underlying pharmacological mechanisms.Methods:In vivo pharmacological effects on ischemic stroke with reperfusion was evaluated using the transient middle cerebral artery occlusion(t-MCAO)mice model.To evaluate short-term outcome,30 mice were randomly divided into vehicle group(n=15)and KXA group(n=15).Mice in KXA and vehicle groups received 69 mg KXA and vehicle for 1 day,respectively.To evaluate longterm outcome,35 mice were randomly divided into sham group(n=5),vehicle group(n=15),and KXA group(n=15).Mice in KXA and vehicle groups received 69 mg KXA and vehicle for 7 days,respectively.Pathological changes in the brain were observed by 2,3,5-triphenyltetrazolium chloride or Nissl stainings,and behavioral assessments,including the Modified Neurologic Severity Score,Bederson score,rotarod test,and adhesive removal test were conducted.The penetration ability of KXA and KX(KXA without propellants)through the blood-brain barrier was assessed both in vitro using a transwell model and in vivo.Furthermore,in vitro effects of KX(5,10,and 20μL/L)on oxygen and glucose deprivation/re-oxygenation(OGD/R)-induced injury,transient receptor potential vanilloid type 1(TRPV1)modulation,calcium influx,and mitochondrial function were explored through Western blot,CCK-8assay,JC-1 staining,calcium imaging,adenosine triphosphate(ATP)and antioxidant measurements.Results:In in vivo experiments,KXA reduced brain infarct volume and neuron loss in t-MCAO mice.Behavioral assessments showed marked improvement in the neurological deficit of t-MCAO mice with KXA treatment(P<0.05 or P<0.01).Additionally,in vitro findings indicated that KX ameliorated OGD/R-induced injury through TRPV1 channel modulation.KX increased cell viability in OGD/R-treated SH-SY5Y cells and prevented OGD/R-induced calcium overload by downregulating TRPV1 expression and constraining calcium influx through TRPV1(P<0.05 or P<0.01).Furthermore,KXA maintained the membrane potential and function of mitochondria in OGD/R-treated SH-SY5Y cells.Conclusions:KXA could attenuate ischemic stroke injury through TRPV1 channel modulation,indicating its potential as a promising therapeutic option for stroke in clinical practice.