Objective To investigate the effect of ultra-low dose of dimethyl sulfoxide(DMSO)on the proliferation of skin fibroblasts and to explore its underlying molecular mechanism.Methods MTT assay was used to determine the effect of different concentrations of DMSO on the proliferation of skin fibroblasts.Pull-down assay with 7-methylguanosine triphosphate(7mGTP)and Western blotting was employed to detect the changes in eukaryotic initiation factor 4E(eIF4E)and its binding protein,4E-BP1,and eukaryotic translation initiation factor 4G(eIF4G).After intervention with mTOR inhibitor,rapamycin,the alterations in the expression and phosphorylation levels of proteins within the PI3K/Akt/mTOR signaling pathway were examined with Western blotting.Results Treatment with 11.0 nmol/L DMSO significantly increased both the cell proliferation rate(P<0.05)and the activity of the cap-dependent translation initiation luciferase reporter gene(P<0.05).Results from 7mGTP pull-down assay and Western blotting demonstrated that 11.0 nmol/L DMSO notably inhibited the binding of 4E-BP1 to eIF4E(P<0.05)while promoting the binding of eIF4G to eIF4E(P<0.05).Compared with the control group,the phosphorylation levels of p-Akt(S473),p-mTOR(S2448),p-4E-BP1(T37/46),and p-p70S6K(T421/424)were upregulated(P<0.05);the total protein expressions of Akt,mTOR,p70S6K,S6,eIF4E,and 4E-BP1 were increased to varying degrees(P<0.05).In the RAPA intervention group,the phosphorylation levels of p-Akt(S473),p-mTOR(S2448),p-p70S6K(T421/424),and p-S6(S235/236)were significantly lower than those in the control group(P<0.05).When comparing the RA+DMSO group with the RA group,the phosphorylation levels of all aforementioned proteins were significantly upregulated except for p-eIF4E(S209)(P<0.05).For protein expression analysis:relative to the control group,the DMSO group exhibited increased expressions of Akt,p70S6K,and mTOR(P<0.05)except for 4E-BP1;the RAPA group showed significant downregulation in all these proteins(P<0.05);compared with the RA group,the RA+DMSO group displayed significantly higher expressions of all these proteins except for p70S6K(P<0.05).Conclusion Ultra-low dose of DMSO(11.0 nmol/L)promotes the proliferation of mouse skin fibroblasts by mediating the PI3K/Akt/mTOR signaling pathway,thereby potentially accelerating wound healing.

Objective To observe the effect of several antihistamines,including epinastine,on the release of leukotriene B4(LTB4),interleukin 4(IL-4)and interleukin 5(IL-5)from spleen lymphocytes of allergic mice challenged by ovalbumin(OVA).Methods OVA-sensitized BALB/c mice were used as animal model of allergy.Spleen lymphocytes isolated from these mice were treated with epinastine(0.1,1.0,10 μmol/L),ebastine(10 μmol/L),cetirizine(10 μmol/L),and dexamethasone(1.0 μmol/L),respectively,followed by incubation with OVA.Those cells without pretreatment with antihistamines served as the control.One hour after the challenge,enzyme-linked immunosorbent assay(ELISA)was applied to measure the level of LTB4,IL-4 and IL-5 in the cell culture supernates.Results Following the incubation with OVA,the levels of LTB4,IL-4 and IL-5 increased significantly in culture supernates of control spleen lymphocytes.Epinastine significantly inhibited the release of LTB4,IL-4 and IL-5 in a dose-dependent manner.At the concentration of 10 μmol/L,the inhibitory effect of epinastine was more potent than that of ebastine and cetirizine for IL-5 and LTB4 release(all P＜0.05):for IL-4,the efrect of epinastine was similar to that of ebastine (P＞0.05)but more potent than that of cetirizine(P＜0.05).Conclusion Epinastine has a potent anti-inflammatory effect.