Norepinephrine(NA),a stress hormone,can accelerate hair graying by binding toβ2 adrenergic receptors(β_(2)AR)on melanocyte stem cells(McSCs).From this,NA-β_(2)AR axis could be a potential target for preventing the ...Norepinephrine(NA),a stress hormone,can accelerate hair graying by binding toβ2 adrenergic receptors(β_(2)AR)on melanocyte stem cells(McSCs).From this,NA-β_(2)AR axis could be a potential target for preventing the stress effect.However,identifying selective blockers forβ_(2)AR has been a key challenge.Therefore,in this study,advanced computer-aided drug design(CADD)techniques were harnessed to screen natural molecules,leading to the discovery of rhynchophylline as a promising compound.Rhynchophylline exhibited strong and stable binding within the active site ofβ_(2)AR,as verified by molecular docking and dynamic simulation assays.When administered to cells,rhyncho-phylline effectively inhibited NA-β_(2)AR signaling.This intervention resulted in a significant reduction of hair graying in a stress-induced mouse model,from 28.5%to 8.2%.To gain a deeper understanding of the underlying mechanisms,transcriptome sequencing was employed,which revealed that NA might disrupt melanogenesis by affecting intracellular calcium balance and promoting cell apoptosis.Importantly,rhynchophylline acted as a potent inhibitor of these downstream pathways.In conclusion,the study demonstrated that rhynchophylline has the potential to mitigate the negative impact of NA on melanogenesis by targetingβ_(2)AR,thus offering a promising solution for preventing stress-induced hair graying.展开更多
Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous chloride.Inhibition of norepinephrine release by clonidine is correlated with motor deficits after motor corte...Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous chloride.Inhibition of norepinephrine release by clonidine is correlated with motor deficits after motor cortex injury.The aim of this study was to analyze the role ofα-adrenergic receptors in the restoration of motor deficits in recovering rats after brain damage.The rats were randomly assigned to the sham and injury groups and then treated with the following pharmacological agents at 3 hours before and 8 hours,3 days,and 20 days after ferrous chloride-induced cortical injury:saline,clonidine,efaroxan(a selective antagonist ofα-adrenergic receptors)and clonidine+efaroxan.The sensorimotor score,the immunohistochemical staining forα-adrenergic receptors,and norepinephrine levels were evaluated.Eight hours post-injury,the sensorimotor score and norepinephrine levels in the locus coeruleus of the injured rats decreased,and these effects were maintained 3 days post-injury.However,20 days later,clonidine administration diminished norepinephrine levels in the pons compared with the sham group.This effect was accompanied by sensorimotor deficits.These effects were blocked by efaroxan.In conclusion,an increase inα-adrenergic receptor levels was observed after injury.Clonidine restores motor deficits in rats recovering from cortical injury,an effect that was prevented by efaroxan.The underlying mechanisms involve the stimulation of hypersensitiveα-adrenergic receptors and inhibition of norepinephrine activity in the locus coeruleus.The results of this study suggest thatαreceptor agonists might restore deficits or impede rehabilitation in patients with brain injury,and therefore pharmacological therapies need to be prescribed cautiously to these patients.展开更多
基金the Shenzhen Science and Technology Innovation Committee(grant numbers JCYJ20200109142444449,JCYJ20210324120007021)the National Natural Science Foundation of China(grant numbers 31801196)Basic and Applied Basic Research Foundation of Guangdong Province(grant numbers 2022A1515110645).
文摘Norepinephrine(NA),a stress hormone,can accelerate hair graying by binding toβ2 adrenergic receptors(β_(2)AR)on melanocyte stem cells(McSCs).From this,NA-β_(2)AR axis could be a potential target for preventing the stress effect.However,identifying selective blockers forβ_(2)AR has been a key challenge.Therefore,in this study,advanced computer-aided drug design(CADD)techniques were harnessed to screen natural molecules,leading to the discovery of rhynchophylline as a promising compound.Rhynchophylline exhibited strong and stable binding within the active site ofβ_(2)AR,as verified by molecular docking and dynamic simulation assays.When administered to cells,rhyncho-phylline effectively inhibited NA-β_(2)AR signaling.This intervention resulted in a significant reduction of hair graying in a stress-induced mouse model,from 28.5%to 8.2%.To gain a deeper understanding of the underlying mechanisms,transcriptome sequencing was employed,which revealed that NA might disrupt melanogenesis by affecting intracellular calcium balance and promoting cell apoptosis.Importantly,rhynchophylline acted as a potent inhibitor of these downstream pathways.In conclusion,the study demonstrated that rhynchophylline has the potential to mitigate the negative impact of NA on melanogenesis by targetingβ_(2)AR,thus offering a promising solution for preventing stress-induced hair graying.
基金supported by Consejo Nacional de Ciencia y Tecnología(CONACy T)project CB 2016-287614(to RGP and ABN)by Scholarship Programa de Apoyo a Proyectos de Investigación e Innovación Tecnológica de la Universidad Nacional Autónoma de México(PAPIIT-UNAM)IA203319 and PAPIIT-UNAM IN216221 to(LERL)。
文摘Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous chloride.Inhibition of norepinephrine release by clonidine is correlated with motor deficits after motor cortex injury.The aim of this study was to analyze the role ofα-adrenergic receptors in the restoration of motor deficits in recovering rats after brain damage.The rats were randomly assigned to the sham and injury groups and then treated with the following pharmacological agents at 3 hours before and 8 hours,3 days,and 20 days after ferrous chloride-induced cortical injury:saline,clonidine,efaroxan(a selective antagonist ofα-adrenergic receptors)and clonidine+efaroxan.The sensorimotor score,the immunohistochemical staining forα-adrenergic receptors,and norepinephrine levels were evaluated.Eight hours post-injury,the sensorimotor score and norepinephrine levels in the locus coeruleus of the injured rats decreased,and these effects were maintained 3 days post-injury.However,20 days later,clonidine administration diminished norepinephrine levels in the pons compared with the sham group.This effect was accompanied by sensorimotor deficits.These effects were blocked by efaroxan.In conclusion,an increase inα-adrenergic receptor levels was observed after injury.Clonidine restores motor deficits in rats recovering from cortical injury,an effect that was prevented by efaroxan.The underlying mechanisms involve the stimulation of hypersensitiveα-adrenergic receptors and inhibition of norepinephrine activity in the locus coeruleus.The results of this study suggest thatαreceptor agonists might restore deficits or impede rehabilitation in patients with brain injury,and therefore pharmacological therapies need to be prescribed cautiously to these patients.
