Objective:To explore if there is premature senescence of chondrocytes in patients with Kashin-Beck disease (KBD) and osteoarthritis.Methods:Five knee cartilage samples of KBD, osteoarthritis and control groups were collected, respectively, from the Second Affiliated Hospital of Xi'an Jiaotong University. DNA was then extracted from cartilage samples and DNA methylation was analyzed by Illumina Infinium HumanMethylation450 BeadChip. At the same time, based on genome-wide methylation data, the online DNA methylation aging clock calculator (https://dnamage.genetics.ucla.edu/home) was used to calculate the DNA methylation age (DNAm age) of samples, and the results were compared with their actual ages.Results:In the comparison between KBD group and control group, 1 212 differentially methylated CpG sites were found, including 497 hypermethylated CpG sites and 715 hypomethylated CpG sites, corresponding to 264 hypermethylated genes and 368 hypomethylated genes, respectively. In the comparison between osteoarthritis group and control group, 656 differentially methylated CpG sites were found, including 343 hypermethylated CpG sites and 313 hypomethylated CpG sites, corresponding to 177 hypermethylated genes and 174 hypomethylated genes, respectively. In the above comparison, 367 overlapped CpG sites (corresponding to 182 genes) were found, which were differentially methylated in both KBD and control groups and osteoarthritis and control groups. The results of DNA methylation aging clock showed that the average age acceleration differences between DNAm age and actual age of KBD, osteoarthritis and control groups were 2.549, 0.017, and - 5.364 years, respectively, the DNAm ages of KBD and osteoarthritis groups were greater than the actual ages.Conclusion:The chondrocytes show premature senescence in both KBD and osteoarthritis.

OBJECTIVE:To systematically review the effect of organic cation transporter 2 [(OCT2)808G>T] gene polymor-phism on the metformin hydrochloride pharmacokinetics in vivo,and to provide evidence-based reference for clinical medication. METHODS:Retrieved from PubMed,EMBase,Foreign Medical Journey Service,CJFD,VIP database and Wanfang database,re-lated studies about the effect of (OCT2)808G>T gene polymorphism on the metformin hydrochloride pharmacokinetics in vivo were collected,and Meta-analysis was performed by using Rev Man 5.1 statistics software. RESULTS:A total of 5 retrospective studies were included,involving 172 patients. The result of gene type was type GT,type TT and type GG. Results of Meta-analysis showed,compared with type GT volunteers,type TT could prolong the half-time period of metformin hydrochloride;compared with type TT,type GG could increase the peak concentration. However,(OCT2)808G>T gene polymorphism had no effects on the renal clearance rate,creatinine clearance rate and area under the drug-time curve. CONCLUSIONS:(OCT2)808G>T gene poly-morphism has certain effect on the half-time period and peak concentration of metformin hydrochloride in vivo of health volunteer, and has no effect on the renal clearance rate,creatinine clearance rate and area under the drug-time curve. Due to the limit of re-search methodological quality,large-scale and high quality studies are required for further validation of the conclusions.

OBJECTIVE:To systematically review the effect of ticagrelor versus prasugrel on platelet reactivity,and provide evi-dence-based reference for clinical treatment. METHODS:Retrieved from PubMed,CJFD and Wanfang Database,randomized con-trolled trials(RCT)about the effect of ticagrelor versus prasugrel on platelet reactivity were collected. Meta-analysis was performed by using Rev Man software after data extract and quality evaluation by Cochrane 5.1.0. RESULTS:Totally 17 RCTs were enrolled,involv-ing 2 757 patients. Results of Meta-analysis showed,regardless of Verity Now(VN)detection method [MD=15.43,95%CI(-0.39, 31.25),P=0.06] or vasodilator stimulus phosphoprotein(VASP)detection method [MD=-3.04,95%CI(-8.98,2.90),P=0.32], ticagrelor and prasugrel had the same effects on platelet reactivity under loading dose,the differences were not statistically significant;regardless of VN detection method [MD=-48.94,95%CI(-58.04,-39.84),P<0.001] or VASP detection method [MD=-14.32, 95%CI(-20.45,-8.20),P<0.001],the effects of ticagrelor were better than prasugrel on platelet reactivity under maintenance dose,the differences were statistically significant. CONCLUSIONS:At the loading dose,there was no difference between ticagrelor and prasugrel,but ticagrelor has more benefits than prasugrel under maintenance dose.

Objective:To systematically review the association between P2Y12 genetic polymorphisms and the clinical safety of clopidogrel in the patients with cardiovascular and cerebrovascular diseases. Methods:Retrieved from MEDLINE,Embase,CNKI,Si-noMed and Wanfang Database (from January 1995 to December 2016),array researches about the association between P2Y12 genetic polymorphisms and the clinical safety of clopidogrel were collected including the studies of patients taking clopidogrel with cardiovascu-lar and cerebrovascular diseases and excluding animal experimental studies. The bias of recruited studies was assessed and meta-analy-sis was performed by RevMan 5.1 software. Results:Totally 10 array researches(3 in English and 7 in Chinese) were enrolled invol-ving 5 223 patients. There were no statistical differences between T allele gene carriers and CC genetype patients of C34T in the inci-dence of adverse cardiovascular events (RR=0.95,95% CI:0.82-1.09,P=0.46). The incidence of adverse cardiovascular events in T allele gene carriers of G52T was higher than that in GG genetype patients(RR=1.99,95% CI:1.63-2.44,P<0.000 01). The incidence of clopidogrel resistance in T allele gene carriers of C34T was higher than that in CC genetype patients(RR=2.02,95% CI:1.37-2.96,P=0.000 4). The incidence of clopidogrel resistance in T allele gene carriers of G52T was higher than that in GG gene-type patients (RR=1.56,95% CI:1.04-2.34,P=0.03). There was no statistical difference in the risk of clopidogrel resistance be-tween C allele gene carriers of i-T744c and T allele gene no-carriers(RR=0.99,95% CI:0.78-1.25,P=0.92). Conclusion:T al-lele gene carriers of C34T might be a risk factor of the occurrence of clopidogrel resistance,T allele gene carriers of G52T might be a risk factor of the occurrence of cardiovascular events and clopidogrel resistance,and C allele gene carriers of i-T744c might not increase the danger of the occurrence of clopidogrel resistance.

Objective To study the effect of DNA-PKcs blocking on the expression of autophagic proteins,and proliferation of esophageal squamous cell carcinoma cells(EC109)after irradiation(X-Ray).Methods NU7441 was used to inhibit DNA-PKcs and X-Ray radiation treatment were used to treat EC109 cells.Th experiment was divided into 4 groups,including control group, NU7441 group,X-Ray group,X-Ray+ NU7441 group.The expressions of autophagy protein Beclin-1 and LC3B were detected by Western blot.Apoptosis was detected by flow cytometry.MTT assay was used to detect cell proliferation.Results The expression of p-DNA-PKcs in EC109 cells was decreased after NU7441 treatment and increased after X-ray irradiation.Compared with untreat-ed cells(control group),the expressions of both Beclin-1 and LC3B in X-Ray+NU7441 group were increased.Compared with the X-Ray group,the expression of Beclin-1 in the X-Ray+NU7441 group was increased.Compared with the control group,the apoptotic rate of EC109 cells in the X-Ray group and X-Ray+NU7441 group was significantly increased,the difference was statistically significant(P<0.05).Compared with the X-Ray group the apoptosis rate in the X-Ray-NU7441 group was significantly increased.The MTT results showed that compared with the control group,the proliferation in the X-Ray group and X-Ray+NU7441 group was significantly inhibited, the difference was statistically significant(P<0.05).Conclusion NU7441 inhibits the expression of DNA-PKcs protein in EC109 cells, which could promote the expressions of autophagy protein Beclin-1 and LC3B,promotes apoptosis and inhibits cell proliferation.

Objective:The unilateral (left) ureteral obstruction (UUO) model was established in mice to explore the changes of renal injury with time and the related mechanisms.Methods:Fifty mice were randomly divided into two groups: sham group and UUO group (UUO model was made by unilateral ureteral ligation). The biochemical indexes, left kidney weight/final weight (LR/BW) and right kidney weight/final weight (RR/BW) of the two groups at different time points were observed, and the left kidney weight/right kidney weight ratio (LR/RR) was calculated. Hematoxylin-eosin (HE), Masson and periodic acid-Schiff (PAS) staining were used to detect the pathological changes of the kidney in mice. Immunofluorescence staining was used to observe the loss of peritubular capillaries (PTC), proliferation of renal parenchymal cells (Ki67 + cells), macrophages (CD68 + markers), infiltration of fibroblasts and expression of Wnt/β-catenin in the kidney of mice. Results:The weight of mice in UUO group decreased rapidly [(18.2±1.1)g vs (22.4±1.2)g] on the third day of modeling, then slowly increased until the 28th day, and significantly decreased [(17.5±0.8)g] on the 60th day; LR/RR and LR/BW increased significantly in the third day, and then decreased gradually; Renal function of mice in UUO group deteriorated significantly on the 60th day [serum creatinine (0.89±0.09)mg/dl, urea nitrogen (41.26±5.65)mg/dl]. In UUO group, renal tubulointerstitial fibrosis and glomerulosclerosis were observed under light microscope in the obstructed kidney; with the passage of time, PTC loss gradually increased; macrophages increased significantly in the left renal parenchyma at first, but began to decrease 28 days later; the number of fibroblasts increased significantly in the first 14 days of the obstructed side (left side) kidney, and then decreased to the normal level; There was no significant difference in the cell number of the non obstructive kidney between UUO group and sham group; The immunofluorescence intensity expression of Wnt/β- catenin of obstructive side (left side) in UUO group was significantly up-regulated in the first 14 days after renal injury, and decreased after 28 days.Conclusions:The development of UUO renal fibrosis involves many changes, including PTC loss, macrophage infiltration, fibroblast activation and expression, but these changes weaken with time.

Objective:To investigate the role of a disintegrin and metalloprotease 12 (ADAM12) gene in chondrocyte injury in patients with Kashin-Beck disease (KBD) and its impact on genes related to insulin-like growth factor binding protein (IGFBP).Methods:Articular cartilage samples were obtained from 5 patients with KBD and 5 control subjects admitted to Honghui Hospital Affiliated to Xi'an Jiaotong University. Chondrocytes were extracted and cultured in vitro. Quantitative real-time PCR (qRT-PCR) and Western blotting were used to detect the expression levels of ADAM12 mRNA and protein in chondrocytes of patients with KBD and control subjects, respectively. Subsequently, ADAM12 gene overexpression was performed using lentivirus in chondrocytes of patients with KBD. MTT assay was used to detect changes in cell viability after ADAM12 gene overexpression, and qRT-PCR was used to detect the mRNA expression levels of chondrocyte differentiation related genes SRY-box transcription factor 9 (SOX9) and type Ⅱ collagen (COLⅡ), apoptosis-related gene B-cell lymphoma/leukaemia-2-associated X protein (BAX), and anabolic related genes IGFBP3 and IGFBP5. Results:The expression levels of ADAM12 mRNA and protein in chondrocytes of patients with KBD (0.57 ± 0.05, 0.81 ± 0.07) were significantly lower than those of control subjects (1.00 ± 0.00, 1.00 ± 0.00), and the differences were statistically significant ( t = - 24.50, - 3.61, P < 0.05). The results of MTT assay showed that the cell viability of chondrocytes in ADAM12 overexpression group (1.09 ± 0.05) was higher than that in empty vector control group (1.00 ± 0.08), and the difference was statistically significant ( t = 4.12, P = 0.031). The results of qRT-PCR showed that compared with empty vector control group, the mRNA expression levels of IGFBP3 (2.35 ± 0.79 vs 0.96 ± 0.25), IGFBP5 (2.13 ± 0.30 vs 0.98 ± 0.34), SOX9 (2.92 ± 0.51 vs 0.94 ± 0.36) and COLⅡ (6.45 ± 2.81 vs 0.87 ± 0.19) in ADAM12 overexpression group were significantly increased, and the differences were statistically significant ( t = 3.19, 5.16, 6.27, 4.10, P < 0.05); while the expression level of BAX mRNA (0.31 ± 0.06 vs 1.02 ± 0.22) was significantly decreased, and the difference was statistically significant ( t = - 11.16, P < 0.001). Conclusion:The ADAM12 gene may have a role in inhibiting apoptosis and promoting differentiation in chondrocyte injury in patients with KBD, and its overexpression can increase expression of IGFBP3 and IGFBP5.

Objective:To investigate the impact of matrix metalloproteinase 13 (MMP13) and low-density lipoprotein receptor-related protein 1 (LRP1) on autophagy of articular chondrocytes in patients with Kashin-Beck disease (KBD).Methods:Human articular cartilage samples obtained from 4 KBD patients and 4 control subjects were collected from Shaanxi Institute for Endemic Disease Prevention and Control, and the expression levels of MMP13 and LRP1 in cartilage tissue were determined using immunohistochemistry (IHC). Chondrocytes were extracted and cultured in vitro, the mRNA and protein expression levels of LRP1 and the autophagy related genes [Beclin 1 (BECN1), microtubule associated protein 1 light chain 3 (LC3)], cartilage injury related genes [MMP13, caspase-3 (CASP3)], chondrocyte differentiation related genes [collagen type Ⅱ alpha 1 chain (COL2A1), and SRY-box transcription factor 9 (SOX9)] were detected by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot (WB), respectively. Chondrocytes from 3 KBD patients were extracted, and MMP13 gene silencing experiment was performed by RNA interference (RNAi) technology, the mRNA and protein expression levels of the above genes were detected by qRT-PCR and WB, respectively. In addition, the antagonist receptor associated protein (RAP) of LRP1 was used to block the LRP1 of human normal chondrocytes (C28/I2 cells), and qRT-PCR and WB were used to detect the mRNA and protein expression levels of LRP1, chondrocyte autophagy, differentiation and cartilage injury related genes, respectively. Results:The IHC results showed that the expression levels of MMP13 (1.67 ± 0.21, 0.59 ± 0.15, 0.51 ± 0.12) in the surface, middle, and deep layers of cartilage tissue of KBD patients were significantly higher than those of control subjects (0.25 ± 0.03, 0.26 ± 0.04, 0.06 ± 0.01), and the differences were statistically significant ( t = - 11.38, P < 0.001; t = - 3.82, - 6.26, P = 0.019, 0.003). The expression levels of LRP1 (0.10 ± 0.02, 0.03 ± 0.01, 0.17 ± 0.03) were significantly lower than those of control subjects (1.63 ± 0.40, 0.44 ± 0.12, 0.34 ± 0.08), and the differences were statistically significant ( t = 6.61, 5.61, 3.64, P = 0.003, 0.005, 0.022). The mRNA and protein expression levels of MMP13, CASP3, SOX9 in chondrocytes of KBD patients were significantly higher than those of control subjects, and the differences were statistically significant ( P < 0.05). The mRNA expression levels of LRP1, LC3, COL2A1 were significantly lower than those of control subjects, and the differences were statistically significant ( P < 0.05). After silencing the MMP13 gene in chondrocytes of KBD patients, there were no significant differences in the mRNA and protein expression levels of LRP1, BECN1, LC3, CASP3, COL2A1, and SOX9 ( P > 0.05). After blocking LRP1 with RAP, the protein expression levels of LRP1, BECN1, LC3, MMP13, COL2A1 and SOX9 in chondrocytes were significantly lower than those in control group ( P < 0.05). Conclusions:There is no direct correlation between MMP13 and abnormal autophagy of articular chondrocytes in KBD patients. After blocking LRP1, the expression of the autophagy related genes BECN1 and LC3 in chondrocytes is decreased.