ABSTRACT
ObjectiveTo investigate the effect and potential mechanism of Dihuangyin on 2， 4-dinitrochlorobenzene （DNCB） -induced model mice with atopic dermatitis （AD）. MethodA mouse model with AD was established by repeatedly stimulating the back skin of mice with DNCB. After successful modeling， the mice were randomly divided into model group， Runzao group （0.78 g·kg-1）， and high， medium， and low dose （40.30， 20.15， and 10.08 g·kg-1） groups of Dihuangyin， with 12 mice in each group， and the blank group consisted of 12 mice， 72 in total. The administration groups were given the corresponding liquid by dose， and the blank group and model group were given the same dose of pure water by intragastric administration， once a day. The skin lesions and scratching times of mice were observed after continuous administration for two weeks. The back skin lesions of mice were stained with hematoxylin-eosin （HE） and toluidine blue to observe the pathology. The contents of serum immunoglobulin E （IgE）， interleukin-4 （IL-4）， interleukin-6 （IL-6）， and interferon-γ （IFN-γ） were detected by enzyme-linked immunosorbent assay （ELISA）. The mRNA expression levels of IFN-γ， IL-4， IL-6， Janus kinase 1 （JAK1）， and transcriptional activator 3 （STAT3） in skin lesion tissue were detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The expressions of JAK1， phosphorylation（p）-JAK1， STAT3， and p-STAT3 proteins in skin lesion tissue were detected by Western blot. ResultCompared with the blank group， the back skin of the model group showed large-scale scab， dryness， erosion， hypertrophy with scratching， epidermal hyperplasia with hyperkeratosis and parakeratosis， hyperacanthosis with edema， and a large number of mast cell infiltration in the dermis， some of which were degranulated. The contents of IgE， IL-4， IL-6， and IFN-γ in the serum of mice were significantly increased （P<0.01）， and the protein expression levels of p-JAK1， STAT3， and p-STAT3 and mRNA expressions of IL-4， IL-6， IFN-γ， JAK1， and STAT3 in skin lesion tissue were significantly increased （P<0.01）. Compared with the model group， only a small amount of dryness and desquamation were observed in the back skin of mice in each administration group， and cell edema was reduced. The inflammatory infiltration was significantly reduced， and the number of mast cell infiltration was significantly decreased. The serum IgE， IL-4， IL-6， and IFN-γ of mice were decreased to varying degrees （P<0.05， P<0.01）. The protein expression levels of p-JAK1， STAT3， and p-STAT3 and mRNA expressions of IL-4， IL-6， IFN-γ， JAK1， and STAT3 in skin lesion tissue were significantly decreased， and the effect of high dose group of Dihuangyin was the best （P<0.01）. ConclusionDihuangyin can improve skin lesions and pruritus in mice with AD， and its mechanism may be related to the effective regulation of cytokines on the helper T cells （Th1）/Th2 axis by interfering with the JAK1/STAT3 signaling pathway and affecting skin barrier function.
ABSTRACT
@#The major reason for the resistance of Gram-negative bacteria to β-lactam antibiotics is the expression of β-lactamases.Metallo-β-lactamases (MBL) hydrolyze almost all types of β-lactam antibiotics including carbapenems, posing a challenge to global public health. Developing MBL inhibitors is an important method to treat the infections caused by resistant bacteria. As an important type of MBL inhibitors, chelating agents can inhibit MBL by chelating, stripping, and binding Zn2+ in the active center of MBL.This review summarizes recent publications on chelators as MBL inhibitors, discussing their chemical structures, inhibitory potency, synergistic effects with antibiotics, selectivity and mechanism of action, including EDTA and related compounds, aspergillomarasmine A (AMA) and its derivatives, NOTA and related compounds, pyridine carboxylic acid and pyridine methylamine compounds, aiming to provide reference for future development of potent, selective and safe clinical MBL inhibitors.
ABSTRACT
Objective To explore renin expression in cytomegalovirus(CMV) infected juxtaglomerular cells(JG) and its biological significance. Methods JG model cell line As4.1 cells derived from kidney tissue were respectively incubated with murine CMV at multiplicities of infection(MOI) of 10, 0.1 and 0 for 5 d, and the control was mock infection with the same amount of ultraviolet inactive CMV as MOI 10, then the cells were harvested. CMV immediate early gene(IE1) mRNA in the cells was tested by RT-PCR. The renin positive cells and the renin fluorescence granules in the cells were examined by immunofluorescence stain. Whether or not re-nin antigen and CMV antigen were showed in the same cells by FITC and TRITC immunofluorescence. The renin gene expression in the cells was individually detected by real-time RT-PCR and Western blot. Results The cells infected by CMV showed typical cytopathic effect(CPE) and viral plaques in the cell monolayer. CMV IE1 mRNA was found in the viral infected cells by RT-PCR. The mass or ring granules of renin positive fluorescence appeared in the cytoplasm of the CPE cells. The renin positive cells congregated around the viral plaques. Renin positive granules and CMV positive granules showed in the same cells. Renin expression in the CMV infected cells exhibited in a dependent manner of ratio of infectious virus particles to cells. Conclusion CMV infection of the cells derived from kidney tissue induces renin expression related to a new pathogenesis of cardiovascular diseases.
