Study On The Protective Effect Of Volatile Oil Of Dendranthema Lavandulifolium On UVB-induced Photodamage Of HaCat Cells

Dendranthema lavandulifolium(Fisch.ex Trautv.),is a plant of the genus Dendranthema in the family Compositae,is mainly distributed in Qinghai,Gansu and Xinjiang.Modern medical research has shown that Asteraceae has anti-inflammatory,antioxidant,hypoglycemic,hypolipidemic and other biological activities.In this study,we took Dendranthema lavandulifolium,a characteristic aromatic plant of Qinghai-Tibet Plateau,as the research object,optimized the extraction process of Dendranthema lavandulifolium volatile oil,determined the main chemical components of Dendranthema lavandulifolium volatile oil by GC-MS,investigated the protective effect of Dendranthema lavandulifolium volatile oil against photodamage based on UVB-induced photoaging model of HaCat cells,and predicted the anti-photoaging mechanism of Dendranthema lavandulifolium volatile oil by combining with network pharmacology.The main studys are as follows:1.The optimal extraction process of Dendranthema lavandulifolium volatile oil was obtained by response surface methodology:material-to-liquid ratio of 1:7,extraction time of 2 h,condensation temperature of-5℃,and the extraction rate of Dendranthema lavandulifolium volatile oil was high(0.404%)under this extraction condition;the composition analysis of the obtained Dendranthema lavandulifolium volatile oil was performed by GC-MS technique,and 126 compounds were detected,mainly terpenoids(monoterpenes,sesquiterpenes,diterpenes)(32.92%),enol class(7.48%),alkenes(13.47%),hydrocarbons(2.46%),aliphatic compounds(4.76%),furans(1.11%),etc.some of which have anti-inflammatory,free radical scavenging effects,such as,mother chrysanthemum azulene(2.64%),trans-nerolidol(1.25%),α-red myrcene alcohol(0.84%),etc.2.Using CCK-8 method to clarify the cytotoxicity of Dendranthema lavandulifolium volatile oil on HaCat cells,selected Dendranthema lavandulifolium volatile oil concentration of 1%,0.5%,0.3%,0.1%,0.01%v/v respectively,the role of2,4,6,8 h,the determination of Dendranthema lavandulifolium volatile oil cytotoxicity concentration of 0.5%v/v;determination found that when the volatile oil concentration of 0.3%,0.1%,0.01%v/v The proliferation rate of HaCat cells reached the maximum after 4 h incubation.3.A UVB-induced photoaging model of HaCat cells was established,and the cell survival rate was measured by the CCK-8 method after irradiation for 5,10,15 and 20min,respectively.The results showed that the difference between the model group and the blank group after 10 min of irradiation was significant(p<0.05),indicating that the photodamage model was successfully established and the irradiation dose was2.4 J/cm~2.4.Fluorescence inverted microscopy revealed that the morphology of HaCat cells in all groups recovered to different degrees after the intervention of Dendranthema lavandulifolium volatile oil.The changes of intracellular SOD,MDA,inflammatory factor IL-6,TNF-αand apoptotic factor Caspase-3 were measured by enzyme-linked immunoassay before and after modeling,and Dendranthema lavandulifolium volatile oil could effectively increase intracellular SOD activity,inhibit MDA production and reduce IL-6,TNF-αand Caspase-3 contents,and the differences were highly significant(p<0.01)compared with the model group.5.Based on the network pharmacology,the 126 chemical components of Dendranthema lavandulifolium volatile oil were predicted to inhibit UVB-induced photodamage protection mechanism in HaCat cells,and 32 compounds,110 targets and 122 pathways were screened by constructing a"Dendranthema lavandulifolium volatile oil chemical component—target—pathway"diagram.The five active ingredients(phytanone,trans-nerolidol,linoleic acid,hinokininyl acetate,nocardone)and five key proteins(AR,CYP19A1,MAPK3,MAPK1,SHBG)were validated by molecular docking,indicating that the active ingredients of Dendranthema lavandulifolium volatile oil can be used to protect HaCat cells from UVB-induced photodamage through the regulation of key targets.components exerted their effects on ameliorating photodamage through key targets of modulation.