Activation of α7 nAChR promotes white fat beiging and heat production in obese mice under cold conditions
10.3969/j.issn.1000-4718.2025.01.007
- VernacularTitle:激活α7 nAChR可促进寒冷条件下肥胖小鼠白色脂肪米色化和产热
- Author:
Hesong FAN
1
;
Sutong WANG
;
Zifang TIAN
;
Liyang GUO
;
Xiao LI
;
Ping JIANG
Author Information
1. 山东中医药大学,山东 济南 250014
- Publication Type:Journal Article
- Keywords:
α7 nicotinic acetylcholine receptor;
obesity;
fat beiging;
inflammation;
macrophages
- From:
Chinese Journal of Pathophysiology
2025;41(1):54-63
- CountryChina
- Language:Chinese
-
Abstract:
AIM:To explore the mechanism by which activation of α7 nicotinic acetylcholine receptor(nAChR)in combination with cold stimulation promotes the beiging of white adipose tissues in obese mice.METHODS:Male C57BL/6J mice,aged 8 weeks,were acclimated for 1 week before fed with high-fat diet(HFD)for 12 weeks to estab-lish an obese model.Fifty mice were randomly divided into 5 groups:control group(low-fat diet),HFD group,model group(HFD+cold stimulation),agonist group(HFD+cold stimulation+α7 nAChR agonist GTS-21),and inhibitor group(HFD+cold stimulation+α7 nAChR inhibitor α-bungarotoxin).Interventions lasted for 4 weeks.Serum levels of total cho-lesterol(TG),triglyceride(TC)and free fatty acid(FFA),and the levels of tumor necrosis factor-α(TNF-α),interleu-kin-1β(IL-1β),IL-10,Toll-like receptor 4(TLR4),nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3),transforming growth factor-β(TGF-β),cyclic adenosine monophosphate(cAMP)and norepinephrine(NE)in while adipose tissues were measured using ELISA.Hematoxylin-eosin(HE)staining was performed to observe morpho-logical changes in white adipose tissues.The mRNA levels of nitric oxide synthase 2(NOS2),arginase 1(Arg1),uncou-pling protein 1(UCP1),peroxisome proliferator-activated receptor γ coactivator-1α(PGC-1α)and PR domain-containing 16(PRDM16)in white adipose tissues were determine by RT-qPCR.Immunohistochemistry was employed to examine the expression levels of CD86,CD206,C/EBP homologous protein(CHOP),immunoglobulin heavy-chain binding protein(BiP)and UCP1.Western blot analysis was conducted to detect the protein levels of CHOP,BiP,UCP1,α7 nAChR,nu-clear factor-κB(NF-κB)p65,phosphorylated Janus kinase 2(p-JAK2)and phosphorylated signal transducer and activa-tor of transcription 3(p-STAT3)in white adipose tissues.RESULTS:Activation of α7 nAChR with GTS-21,combined with cold-induced thermogenesis,led to decreased levels of TC,TG and FFA in peripheral blood and reduced lipid droplet area in white adipose tissues.Additionally,α7 nAChR activation resulted in decreased expression of TLR4 and NLRP3.In white adipose tissue,there was an increase in Arg1 mRNA level and CD206 expression,while NOS2 mRNA level and CD86 expression decreased.Phosphorylation of the JAK2/STAT3 pathway was up-regulated,and NF-κB p65 level de-creased.The levels of pro-inflammatory cytokines TNF-α and IL-1β were reduced,whereas the levels of anti-inflammatory factors TGF-β and IL-10 increased.Expression of CHOP and BiP also declined.Furthermore,α7 nAChR activation in-creased the mRNA levels of PRDM16 and PGC-1α,as well as UCP1 expression in white adipose tissues.CONCLUSION:Activation of α7 nAChR combined with cold stimulation not only promotes the beiging of white adipose tissue in obese mice,but also alliviates metabolic disorders,thereby enhancing the thermogenic efficiency of white adipose tissue beiging.
