1.Effect of homocysteine on the intestinal permeability by regulating MEK-ERK-MLCK signal transduction in experimental colitis rats
Shaozhen DING ; Hao DING ; Qiao MEI ; Xiaochang LIU ; Jing HU ; Yongmei HU ; Jianming XU
Chinese Pharmacological Bulletin 2016;32(4):498-502
Aim To investigate whether Hcy influenced the intestinal mucosal permeability by regulating MEK-ERK-MLCK pathway. Methods SD rats were divided into 4 groups:normal group, normal+Hcy group, TN-BS/ethanol group, TNBS/ethanol+Hcy group. Experi-mental colitis model with hyperhomocystinemia was es-tablished in rats with intracolonic administration of TN-BS and subcutaneous injection of Hcy. The colonic mucosal tissue was collected for histopathological exam-ination and activity of myeloperoxidase ( MPO ) . The protein expression of MLCK, p-MLCK, MEK, ERK and p-ERK in intestinal mucosal tissues was examined by Western blot method. The mRNA expression of ML-CK was examined by RT-qPCR method. Result Com-pared with the normal group and TNBS group, the DAI and HI scores and the MPO activity were increased in TNBS/ethanol+Hcy group ( P <0. 01 ) . Western blot and RT-qPCR showed that expression of MLCK, p-ML-CK, MEK, ERK and p-ERK increased in small intes-tine in TNBS/ethanol+Hcy group. Conclusion Hcy can increase intestinal permeability in TNBS-induced colitis rats by regulating the expression of MEK-ERK-MLCK signal pathway.
2.Moxifloxacin-based triple therapy for helicobacter pylori eradication in type 2 diabetic patients
Shaozhen WANG ; Yanan SHI ; Bixiao CHEN ; Jing ZHAO ; Jinjin LI ; Xinyu LIU ; Lei GUO ; Kun FU ; Yanguang XU
Chinese Journal of General Practitioners 2009;8(8):563-565
Alc in trial group were significant better than those in control group ( P < 0. 05 ). The results indicate that type 2 diabetic patients with Hp infection should receive moxifloxacin-based triple therapy as first-line treatment.
3.New understanding and trends in the diagnosis and management of dry eye
Yingli LI ; Zuguo LIU ; Yingping DENG ; Jing HONG ; Ying JIE ; Xiuming JIN ; Wei LI ; Lingyi LIANG ; Hua WANG ; Jin YUAN ; Hong ZHANG ; Mingchang ZHANG ; Shaozhen ZHAO
Chinese Journal of Experimental Ophthalmology 2020;38(3):161-164
An expert consensus about the clinical diagnosis and treatment of dry eye was documented in 2013 by a corneal expert group of Chinese Ophthalmological Society.However, due to the rapid development of diagnostic and therapeutic devices of dry eye, researoh on dry eye has made significont progress in China since then.Consequently, the existing expert consensus cannot meet the needs of clinical practice.It is therefore urgent to develop a series of standardized diagnosis and treatment protocols, and publish a new consensus of experts and an operating guideline.At the same time, basic, clinical, and translational research on dry eye should be promoted to provide better services to the patients with dry eyes.On January 12, 2019 many experts in the field of dry eye in China held a panel discussion of dry eye study in Guangzhou to analyze the current development status and trends in the field of dry eye in China and abroad.In that meeting, opinions and recommendations were put forward based on a new understanding of the definition of dry eye, new concepts of dysfunctional dry eye, advances its diagnosis and classification, refinement and standardization of dry eye treatment, and the future development of dry eye research.
4.A robust luminescent assay for screening alkyladenine DNA glycosylase inhibitors to overcome DNA repair and temozolomide drug resistance
Ying-Qi SONG ; Guo-Dong LI ; Dou NIU ; Feng CHEN ; Shaozhen JING ; Vincent Kam Wai Wong ; Wanhe WANG ; Chung-Hang LEUNG
Journal of Pharmaceutical Analysis 2023;13(5):514-522
Temozolomide(TMZ)is an anticancer agent used to treat glioblastoma,typically following radiation therapy and/or surgical resection.However,despite its effectiveness,at least 50%of patients do not respond to TMZ,which is associated with repair and/or tolerance of TMZ-induced DNA lesions.Studies have demonstrated that alkyladenine DNA glycosylase(AAG),an enzyme that triggers the base excision repair(BER)pathway by excising TMZ-induced N3-methyladenine(3meA)and N7-methylguanine le-sions,is overexpressed in glioblastoma tissues compared to normal tissues.Therefore,it is essential to develop a rapid and efficient screening method for AAG inhibitors to overcome TMZ resistance in glio-blastomas.Herein,we report a robust time-resolved photoluminescence platform for identifying AAG inhibitors with improved sensitivity compared to conventional steady-state spectroscopic methods.As a proof-of-concept,this assay was used to screen 1440 food and drug administration-approved drugs against AAG,resulting in the repurposing of sunitinib as a potential AAG inhibitor.Sunitinib restored glioblastoma(GBM)cancer cell sensitivity to TMZ,inhibited GBM cell proliferation and stem cell char-acteristics,and induced GBM cell cycle arrest.Overall,this strategy offers a new method for the rapid identification of small-molecule inhibitors of BER enzyme activities that can prevent false negatives due to a fluorescent background.
5.Comparison of pharmacodynamics between different batches of recombinant decoy receptor innovative drug RC28-E1 and RC28-E2 in retinal angiogenesis and neovascularization and its mechanism
Zhongxiu GU ; Jing JIANG ; Min HUANG ; Mianmian WU ; Fang GUO ; Shenjun LI ; Jianmin FANG ; Shaozhen ZHAO ; Yan ZHANG
Chinese Journal of Experimental Ophthalmology 2018;36(8):581-589
Objective To compare the pharmacodynamics between different batches of recombinant decoy receptor innovative drug RC28-E1 and RC28-E2 in retinal angiogenesis and neovascularization,and analyze its mechanism.Methods Sixty postnatal Day 4 (P4) C57BL/6J mice were randomly divided into normal control group,vascular endothelial growth factor (VEGF)+fibroblast growth factor 2 (FGF2) group,VEGF+FGF2+RC28-E1 group,VEGF+FGF2+RC28-E2 group,VEGF+FGF2+conbercept group and VEGF+FGF2+FGF trap group by using a random number table,with 10 mice in each group.The mouse retinal explant culture system was established,and stimulated with the corresponding factors and drugs prepared in the starving culture media.The normal controls were treated with the starving media.Then the retinal explants were stained with Isolectin B4 and imaged.The number of filopodia per vascular length was quantified.In addition,ninety-six P7 C57BL/6J mice were randomly divided into normal control group,oxygen-induced retinopathy (OIR) model control group,OIR + RC28-E1 group,OIR + RC28-E2 group,OIR+conbercept group and OIR+FGF trap group by using a random number table,with 16 mice in each group.The normal controls were raised under normoxia for 10 days,and the rest of the groups were raised under hyperoxia for 5 days,then returned to normoxia for another 5 days.On P17,the retinas were isolated and stained with Isolectin B4.The stained retinas were mountedon the slides and photographed.The relative vessel obliteration and neovascularization in retina were analyzed with computer software.Then the protein levels of VEGF and FGF2 were examined by Western blot in the retinas of each group in the OIR experiment.Finally,in the RF/6A cells stimulated with VEGF and FGF2,the activities of the signaling pathways,including MEK-extracellular regulated protein kinases (Erk),protein kinase C (PKC) and protein kinase B (Akt) pathways,were examined by Western blot.All experimental procedures were evaluated and approved by the Institutional Animal Care and Use Committee of Tianjin Medical University (SYXK 2009-0001),and were in accordance with the ARVO Statement for the Use of Animals in Ophthalmic and Vision Research.Results The results of retinal explant cultures showed that the numbers of filopodia per vascular length in VEGF + FGF2 + RC28-E1,VEGF + FGF2 + RC28-E2,VEGF + FGF2 + conbcrcept,and VEGF+FGF2+FGF trap groups were all significantly less than that in the VEGF+FGF2 group (all at P < 0.001).The filopodia number in retinal vascular front in RC28-E1 group was similar to that in the RC28-E2 group (P =0.15),whereas the filopodia numbers in both groups were significantly decreased as compared to those in VEGF+ FGF2+conbercept group and VEGF+FGF2+FGF trap group (all at P<0.001).The results from the OIR mouse model showed that the relative vessel obliteration area in OIR model control group was dramatically higher than those in the drug intervention groups (all at P<0.05).There was no statistical significance in the relative vessel obliteration area between OIR+RC28-E1 group and OIR+RC28-E2 group (P =0.17),while the obliteration areas in both RC28-E-intervened groups were significantly lower than those in the OIR+conbercept group and OIR+FGF trap group (all at P<0.05).The relative neovascular pixels in the intervention groups were significantly lower than those in the OIR model control group (all at P<0.001).The neovascular pixels in OIR+RC28-E1 group were significantly lower than those in VEGF+FGF2+conbercept group and VEGF + FGF2 + FGF trap group (both at P < 0.05),but comparable to those in OIR+RC28-E2 group (P =0.39).Western blot result showed that,the protein expression of VEGF and FGF2 in the OIR mouse retinas were significantly upregulated compared to those in the normal ones (both at P<0.001).The upregulation of both genes were normalized by both RC28-E1 and RC28-E2.In addition,the stimulation of VEGF and FGF2 induced an enhanced activity in MEK-Erk pathway in RF/6A cells,whereas RC28-E1 inhibited the overactivation.Conclusions RC28-E1 and RC28-E2 both can inhibit angiogenesis in the retinal explants isolated from neonatal mice;they also reduce vessel obliteration and mitigate neovascularization in the OIR mouse model.Therefore,the pharmacology batch and pilot test batch of RC28-E have similar efficacies and reliable stability,and are superior in the anti-angiogenic and anti-neovascular efficacy to the currently clinically available drugs conbercept and FGF trap.RC28-E1 may suppress pathological neovascularization through inhibiting the overactivation of MEK-Erk pathway in retinal vascular endothelial cells.