Increased Chondrocyte Apoptosis in Kashin-Beck Disease and Rats Induced by T-2 Toxin and Selenium Deficiency / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate chondrocyte apoptosis and the expression of biochemical markers associated with apoptosis in Kashin-Beck disease (KBD) and in an established T-2 toxin- and selenium (Se) deficiency-induced rat model.</p><p><b>METHODS</b>Cartilages were collected from the hand phalanges of five patients with KBD and five healthy children. Sprague-Dawley rats were administered a selenium-deficient diet for 4 weeks prior to T-2 toxin exposure. The apoptotic chondrocytes were observed by terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Caspase-3, p53, Bcl-2, and Bax proteins in the cartilages were visualized by immunohistochemistry, their protein levels were determined by Western blotting, and mRNA levels were determined by real-time reverse transcription polymerase chain reaction.</p><p><b>RESULTS</b>Increased chondrocyte apoptosis was observed in the cartilages of children with KBD. Increased apoptotic and caspase-3-stained cells were observed in the cartilages of rats fed with normal and Se-deficient diets plus T-2 toxin exposure compared to those in rats fed with normal and Se-deficient diets. Caspase-3, p53, and Bax proteins and mRNA levels were higher, whereas Bcl-2 levels were lower in rats fed with normal or Se-deficiency diets supplemented with T-2 toxin than the corresponding levels in rats fed with normal diet.</p><p><b>CONCLUSION</b>T-2 toxin under a selenium-deficient nutritional status induces chondrocyte death, which emphasizes the role of chondrocyte apoptosis in cartilage damage and progression of KBD.</p>

Role of JNK signaling pathway in chondrocyte apoptosis induced by nitric oxide / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the role of c-jun N-terminal kinase (JNK) signaling pathway in chondrocyte apoptosis induced by nitric oxide (NO) using NO donor sodium nitroprusside (SNP) and JNK inhibitor SP600125.</p><p><b>METHODS</b>Articular chondrocytes were separated from New Zealand rabbits aged 3 weeks by mechanical digestion and enzyme digestion and identified by toluidine blue staining, and then the chondrocytes were treated with SNP and SP600125 for 24 h. The cell apoptosis was evaluated by Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) flow cytometry and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL), and the expression levels of nuclear factor-kappa B (NF-κB) p65 and p53 were measured by western blot.</p><p><b>RESULTS</b>Compared with those in control group, the early apoptotic rate of SNP-treated chondrocytes increased as the concentration of SNProse, exhibiting a concentration dependency (P < 0.05), and the expression levels of NF-κB p65 and p53 also increased (P < 0.05); JNK inhibitor SP600125 inhibited these increases (P < 0.05).</p><p><b>CONCLUSION</b>JNK signaling pathway plays an important role in NO-induced chondrocyte apoptosis. JNK inhibitor SP600125 can reduce NO-induced apoptosis and expression of NF-κB p65 and p53 in articular chondrocytes of rabbits in a concentration-dependent manner.</p>

Serum malondialdehyde level and activities of antioxidant enzymes of children from Kaschin-Beck disease areas of Xinghai county in Qinhai province / 中国地方病学杂志

Objective To observe the activities of serum peroxidase capacity,and lipid peroxidation of children from Kaschin-Beck disease (KBD) areas of Xinghai county in Qinhai province,and to explore the relationship between antioxidant capacity and KBD.Methods Sixty four KBD and forty six health subjects without KBD were chosen from KBD endemic areas,which included primary schools of Tangnaihai,Xialujuan and Qushian of Xinghai county in Qinghai province,and fifty nine age-matched healthy control subjects without KBD were from a non-KBD endemic area,Nanfan primary school of Chang'an county in Shaanxi province.Twenty patients with KBD and twenty control subjects from KBD areas and non-KBD area were extracted by simple random sampling method.2,3-DAN fluorescence technique was used to test the hair and blood selenium.The biochemical techniques were used to test the indicators of oxidative stress including malondialdehyde(MDA),antioxidant enzyme activities,total antioxidant capacity(T-AOC),serum superoxide dismutase(SOD),catalase(CAT) and glutathione peroxidase(GSHPx).ResultsAll patients with KBD had significantly lower serum GSH-Px activities[ (59.53 ± 25.23)kU/L] and selenium levels in hair[ (67.64 ± 17.28)μg/L] and blood[(36.27 ± 13.29)μg/L],respectively,than that of control subjects from KBD areas [ ( 91.88 ± 22.99 ) kU/L,( 153.32 ± 24.31 ) μg/L,( 63.06 ± 13.66) μg/L ] and nonKBD areas[ ( 122.68 ± 41.74)kU/L,(242.35 ± 38.56)μg/L,(98.93 ± 17.18)μg/L,all P ＜ 0.05].Serum MDA levels in KBD patients[ (4.64 ± 1.11 )μmol/L] were significantly higher than that in control subjects from KBD [(3.31 ± 1.22)μmol/L] and non-KBD areas[ (3.43 ± 1.29)μmol/L,all P ＜ 0.05].On the other hand,T-AOC,SOD and CAT activities were significantly higher in both KBD[(19.80 ± 6.64),(55.80 ± 8.14),(16.45 ± 5.61 ) kU/L] and control subjects[ (21.71 ± 8.82),(57.45 ± 6.96),(15.63 ± 9.18)kU/L] from KBD areas than that of control subjects from non-KBD area[ (13.56 ± 5.38),(42.79 ± 8.10),(6.05 ± 2.71 )kU/L,all P ＜ 0.05 ].Hair selenium levels,blood selenium levels and GSH-Px activity of control subjects from KBD areas were,respectively,significantly lower than that in control subjects from non-KBD area(all P ＜ 0.05).Conclusions These findings strongly confirm the evidence that KBD patients are susceptible to oxidative stress.The results also show the increase in antioxidant enzymes,which could probably be due to adaptive response to pro-oxidant in KBD state.Hence,there seems to be an imbalance between oxidant and antioxidant systems in KBD patients.

Effect of Tanshinone II A on expression of EGF and EGFR in hepatocellular carcinoma cell line SMMC-7721 / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To observe the effect of Tanshinone II A on the expression of epidermal growth facter (EGF) and epidermal growth facter recepter (EGFR) in human hepatocellular carcinoma cell line SMMC-7721.</p><p><b>METHODS</b>The human hepatocellular carcinoma SMMC-7721 cells cultured in vitro was treated with different concentrations of Tanshinone II A. The proliferation of the cells was measured by MTT assay, and the apoptosis of the cells was investigated by flow cytometry and cytochemical staining with Hoechst 33342. The expression of EGF and EGFR was detected by immunocytochemistry method. The levels of EGF in medium were measured by radioimmunoassay.</p><p><b>RESULT</b>Tanshinone II A inhibited the growth of SMMC-7721 cells remarkably in a dose-dependent manner. The inhibitory rate reached the peak (72.5%) after 0.5 microg/ml Tanshinone II A was used for 48 h, which was significantly higher than that in the controls (P<0.05). FCM analysis showed that when SMMC-7721 cells were treated with 0.5 microg/ml Tanshinone II A, the apoptosis rates for 24 h, 48 h and 72 h were (4.06+/-0.27)%, (7.58+/-0.56)% and (5.23+/-0.13)%, respectively which were markedly higher than those in the controls (all P<0.01). SMMC-7721 cell apoptosis with cell shrinkage, nuclear chromatin concentration and fragmentation as well as the formation of apoptotic bodies were observed by cytochemical staining when treated with Tanshinone II A. The immunocytochemistry showed that the expressions of EGF and EGFR were down regulated while the concentration of Tanshinone II A was increasing. The high expression rates for EGF and EGFR were 10%, 20%, respectively, and the gray scale was 181.52+/-1.63, 179.37+/-1.59, which were markedly higher than those in the controls (all P<0.05). The levels of EGF in medium measured by radioimmunoassay were decreased significantly after Tanshinone II A treatment.</p><p><b>CONCLUSION</b>Tanshinone II A can inhibit cell proliferation and induce apoptosis in hepatocellular carcinoma cell line SMMC-7721, which may be related to the down-regulation of EGF and EGFR protein expression.</p>

T-2 toxin-induced apoptosis involving Fas, p53, Bcl-xL, Bcl-2, Bax and caspase-3 signaling pathways in human chondrocytes / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>To investigate the effects of T-2 toxin on expressions of Fas, p53, Bcl-xL, Bcl-2, Bax and caspase-3 on human chondrocytes.</p><p><b>METHODS</b>Human chondrocytes were treated with T-2 toxin (1-20 ng/ml) for 5 d. Fas, p53 and other apoptosis-related proteins such as Bax, Bcl-2, Bcl-xL, caspase-3 were determined by Western blot analysis and their mRNA expressions were determined by reverse transcriptase-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>Increases in Fas, p53 and the pro-apoptotic factor Bax protein and mRNA expressions and a decrease of the anti-apoptotic factor Bcl-xL were observed in a dose-dependent manner after exposures to 1-20 ng/ml T-2 toxin, while the expression of the anti-apoptotic factor Bcl-2 was unchanged. Meanwhile, T-2 toxin could also up-regulate the expressions of both pro-caspase-3 and caspase-3 in a dose-dependent manner.</p><p><b>CONCLUSION</b>These data suggest a possible underlying molecular mechanism for T-2 toxin to induce the apoptosis signaling pathway in human chondrocytes by regulation of apoptosis-related proteins.</p>

Expression of specific antibodies against platelet glycoproteins in patients with mds and its significance / 中国实验血液学杂志

The aim of this study was to find platelet specific autoantibodies against glycoproteins in myelodysplastic syndrome (MDS) and to explore its role in pathogenesis of MDS. The plasma autoantibodies against GP IIb/IIIa and GP Ib/IX were measured by using a modified monoclonal antibody specific immobolization platelet antigens assay (MAIPA). Absorbance greater than mean value plus tripled standard deviation recorded from the normal controls were regarded as positive. The results indicated that the total positive rate in patients with MDS was 16.67% (5/30), the total positive rate in patients with ITP was 46.67% (14/30), the difference between MDS group and ITP group was significant (P < 0.05). It is concluded that partial patients with MDS have plasma specific autoantibodies against platelet GP II b/III a and GP Ib/IX, indicating correlation of thrombocytopenia of patients with immune factors and the autoantibody-mediated platelet destruction may be involved in the pathogenesis of MDS. It provides a new basis for immunosuppression therapy for MDS.

Protective effect of selenium against T-2 toxin-induced inhibition of chondrocyte aggrecan and collagen II synthesis / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the inhibitory effect of T-2 toxin on the expression of aggrecan and collagen II in chondrocytes and the protection of selenium against this effect.</p><p><b>METHODS</b>Human chondrocytes cultured in vitro were treated with T-2 toxin at different concentrations for varied time periods (1-5 days), and the cell viability was measured by MTT assay. Aggrecan expression was detected by toluidine blue staining and collagen II expression by immunostaining using monoclonal antibody of collagen. Aggrecan and collagen II mRNA expressions were measured by semiquantitative RT-PCR.</p><p><b>RESULTS</b>T-2 toxin dose- and time-dependently affected chondrocyte viability within the concentration range of 0.001-2 mg/L, the prolonged treatment time further enhanced the dose dependence of the inhibitory effect. T-2 toxin lowered aggrecan and collagen II synthesis in the chondrocytes and reduced their mRNA expressions. Selenium could partly attenuate the inhibitory effects of T-2 toxin on aggrecan mRNA expression, but showed no such effect against T-2-induced collagen II expression.</p><p><b>CONCLUSION</b>T-2 toxin can obviously inhibit aggrecan and collagen II synthesis in human chondrocytes, and selenium can partly antagonize the inhibitory effects of T-2 toxin on aggrecan.</p>