脱氧雪腐镰刀菌烯醇（DON）致鸡胚软骨细胞损伤及硒的保…

本实验观察了脱氧雪腐镰刀菌烯醇（ＤＯＮ）对鸡胚关节软骨的作用。结果表明，ＤＯＮ对关节软骨细胞具有明显的毒性作用，其超微结构的改变主要为软骨细胞膜系统的损伤。软骨细胞质膜节段性缺损；线粒体嵴断裂溶解，膜结构模糊；粗面内质网断裂，核蛋白体脱粒；并出现大量变性空泡；软骨基质变疏松、崩解。在给予相同剂量的同时，补充５μｇ硒，软骨细胞损伤程度明显减轻，质膜、核膜均完整，软骨基质未见异常，仅见部分核蛋白体脱粒     

脱氧雪腐镰刀菌烯醇对培养软骨细胞影响的超微结构观察

采用体外软骨细胞培养方法，观察脱氧雪腐镰刀菌烯醇（ＤＯＮ）对幼兔关节软骨细胞超微结构的作用，结果表明ＤＯＮ对软骨细胞膜系统和细胞器具有明显的损伤作用，特别是对培养早期的软骨细胞具致命损伤。ＤＯＮ与大骨节病关系待进一步探讨。     

镰刀菌毒素对软骨细胞的损伤及硒的保护作用

单端孢霉烯族化合物Ｔ－２毒素引起鸡胚关节软骨产生变性改变，其超微结构的变化主要为软骨细胞膜系统的损伤。具体表现为软骨细胞质膜节段性缺损；线粒体肿胀，嵴断裂、变短、溶解，部分线粒体空泡化；粗面内质网呈池状扩张增多；细胞核电子密度增高核膜扩张形成核周池，并出现节段性破损；胞浆疏松，胞浆内出现髓样小体和变性空泡；软骨细胞边缘软骨基质变疏松。硒可以保护Ｔ－２毒素对软骨细胞的损伤。Ｔ－２毒素对软骨细胞的损…     

串珠镰刀菌素对软骨细胞作用的实验研究

本实验用不同浓度的串珠镰刀菌素作用于体外培养不同时期的兔关节软骨细胞，动态观察ＭＯＮ对软骨细胞结构和生长代谢功能的影响。结果显示ＭＯＮ影响软骨细胞ＤＮＡ的合成和细胞的分裂增殖，特别在细胞培养的早期，作用更为明显；同时也影响到细胞的结构和代谢功能。ＭＯＮ的作用机理和与大骨节病的关系有待进一步研究。     

脱氧雪腐镰刀菌烯醇（DON）对培养软骨细胞生长代谢的影响

本文报告了脱氧雪腐镰刀菌烯醇（ＤＯＮ）对培养软骨细胞生长代谢的影响。结果显示：在一代兔关节软骨细胞培养２４ｈ时，仅在培养液中加入１．０μｇ／ｍｌ的ＤＯＮ，即对软骨细胞产生致命性的损伤。在培养１２０ｈ时加ＤＯＮ，其毒性作用随ＤＯＮ浓度升高而损伤加重。在培养２１６ｈ时加入２．５μｇ／ｍｌ以下的ＤＯＮ，对软骨细胞的生长代谢没有明显的影响。简单讨论了ＤＯＮ与大骨节病的关系。     

串珠镰刀菌素（MON）及硒对中国小型猪关节软骨作用的实验研究

中国实验用小型猪在低硒饲料条件下，分别饲喂串珠镰刀菌素和硒三个月，观察动物前后肢软骨的病理变化及软骨基质中胶原及蛋白聚糖三组分含量的变化。结果表明串珠镰刀菌素对软骨组织具有较强的毒性作用，能致小型猪关节软骨深层发生类似人类大骨节病样的带状或片状坏死，并使软骨基质中蛋白聚糖含量降低，而单纯低硒并不能引起类似的损害。补硒能在一定程度上拮抗串珠镰刀菌素的毒性作用，使病变严重程度减轻，改善基质的生化代谢。     

雪腐镰刀菌烯醇致软骨细胞的损伤作用

应用不同浓度的雪腐镰刀菌烯醇（ＮＩＶ）作用于培养的兔软骨细胞，动态观察ＮＩＶ对软骨细胞生长代谢的影响。结果显示ＮＩＶ能使软骨细胞中的ＤＮＡ，基质中的葡萄糖醛酸（ＧＬｃＵＡ）和碱性磷酸酶（ＡＫＰ）含量降低。表明ＮＩＶ对软骨细胞具有明显的毒性损伤作用，能够引起软骨细胞的形态结构和代谢功能的改变。     

雪腐镰刀菌烯醇和硒对培养软骨组织CD44表达的影响

目的 研究大骨节病(KBD)有关病因因素对靶组织细胞的损伤和保护作用;探索引起软骨细胞变性坏死的机制。方法 采用细胞培养法于体外再建软骨组织模型,并加入KBD可疑致病因子雪腐镰刀菌烯醇(NIV)和保护因子硒,检测软骨细胞膜上透明质酸受体CD44和细胞培养液中可溶性CD44(SoCD44)。结果 软骨细胞膜上CD44的表达随着,NIV浓度的增加而减少,加硒后有增加趋势;细胞培养液中SoCD44浓度随NIV浓度升高逐渐降低,但高浓度组出现了增高,加硒后趋势不变;除对照组与加硒对照组外,组间差异有统计学意义(P<0.05)。结论 NIV能干扰软骨细胞表面粘附分子CD44表达,进而引起软骨细胞外基质代谢紊乱;补硒能够拮抗NIV对软骨细胞的损伤,但作用有限。     

T—2毒素,MON和硒对中国小型猪罹患骨软骨病的影响

中国小型猪在低硒（３５ｎｇ／ｋｇ）饲料喂养条件下投给Ｔ－２毒素（１．５ｍｇ／ｋｇ饲料）成串珠镰刀菌素（ＭＯＮ，１ｍｇ／ｋｇ体重）１０５天，观察了动物前、后肢软骨的病理变化，首次证实所用的纯系农大Ｉ号小型猪可以发生与家猪相同的骨软骨病（ＯＣ），出现三种类型ＯＣ损害。其中第三型损害（关节软骨深层带状、片状坏死）与Ｔ－２毒素和ＭＯＮ的投给关系明显，与单纯的低硒饲养无关；给毒的同时补给亚硒酸钠（使饲料含硒     

真菌毒素DON,T—2和NIV对培养软骨细胞作用的实验研究

采用软骨细胞体外单层培养方法，观察ＤＯＮ、Ｔ－２毒素和ＮＩＶ对幼兔关节软骨细胞的作用。结果显示；三种毒素对培养的软骨细胞均有较强的毒性作用，能抑制ＤＮＡ的合成和细胞的分裂增殖，特别是在培养的早期，亦即在细胞分离时受到的损伤尚未完全恢复和细胞分裂增殖的旺盛时期，其损伤作用更为明显。     

脱氧雪腐镰刀菌烯醇致新西兰家兔关节损伤的实验观察

目的 观察脱氧雪腐镰刀菌烯醇(DON)对新西兰家兔膝关节软骨和滑膜的损伤.方法 将15只成年雄性新西兰家兔随机分为3组,对照组正常饲养,高、低剂量组分别投予0.10、0.05 mg/kg剂量的DON,经耳缘静脉注射隔日染毒.20 d后处死家兔,取双侧膝关节,进行常规病理检查,测定关节冲洗液白细胞介素1β(IL-1β)、肿瘤坏死因子α(TNF-α)、一氧化氮(NO)水平.结果 光镜下,可见低、高剂量组家兔膝关节软骨细胞变性、坏死.滑膜组织炎细胞浸润.关节冲洗液IL-1β、TNF-α、NO,组间比较差异有统计学意义(F值分别为19.396、18.195、22.136,P＜0.05);与对照组[(0.113±0.043)、(0.138±0.087)μg/L、(23.56±9.35)μmol/L]比较,高剂量组[(0.451±0.091)、(0.575±0.122)μg/L,(70.27±11.53)μmol/L]和低剂量组[(0.295±0.107)、(0.387±0.131)μg/L,(45.32±12.24)μmol/L]明显增高(P＜0.05),且高剂量组高于低剂量组(P＜0.05).结论 DON可导致家兔关节软骨和滑膜损伤,其损伤类似于人骨关节炎病变.DON可能是骨关节炎的病因之一.     

Inhibition of beta-catenin signaling in articular chondrocytes results in articular cartilage destruction

OBJECTIVE: Osteoarthritis is a degenerative joint disease whose molecular mechanism is currently unknown. Wnt/beta-catenin signaling has been demonstrated to play a critical role in the development and function of articular chondrocytes. To determine the role of beta-catenin signaling in articular chondrocyte function, we generated Col2a1-ICAT-transgenic mice to inhibit beta-catenin signaling in chondrocytes. METHODS: The expression of the ICAT transgene was determined by immunostaining and Western blot analysis. Histologic analyses were performed to determine changes in articular cartilage structure and morphology. Cell apoptosis was determined by TUNEL staining and the immunostaining of cleaved caspase 3 and poly(ADP-ribose) polymerase (PARP) proteins. Expression of Bcl-2, Bcl-x(L), and Bax proteins and caspase 9 and caspase 3/7 activities were examined in primary sternal chondrocytes isolated from 3-day-old neonatal Col2a1-ICAT-transgenic mice and their wild-type littermates and in primary chicken and porcine articular chondrocytes. RESULTS: Expression of the ICAT transgene was detected in articular chondrocytes of the transgenic mice. Associated with this, age-dependent articular cartilage destruction was observed in Col2a1-ICAT-transgenic mice. A significant increase in cell apoptosis in articular chondrocytes was identified by TUNEL staining and the immunostaining of cleaved caspase 3 and PARP proteins in these transgenic mice. Consistent with this, Bcl-2 and Bcl-x(L) expression were decreased and caspase 9 and caspase 3/7 activity were increased, suggesting that increased cell apoptosis may contribute significantly to the articular cartilage destruction observed in Col2a1-ICAT-transgenic mice. CONCLUSION: Inhibition of beta-catenin signaling in articular chondrocytes causes increased cell apoptosis and articular cartilage destruction in Col2a1-ICAT- transgenic mice.     

MMP-2/gelatinase A is a gene product of human adult articular chondrocytes and is increased in osteoarthritic cartilage

OBJECTIVE: Collagen fibril degeneration involves initially the cleavage within the triple helix by the collagenases (1 and 3), but then mainly involves also the gelatinases, of which gelatinase A (MMP-2) appears to play a central role in many tissues. The objective of this study was to determine the quantitative expression levels as well as the distribution in normal and osteoarthritic cartilage of gelatinase A and in cultured articular chondrocytes with and without stimulation by Il-1beta. METHODS: Conventional and online PCR technology and immunohistochemistry were used to determine MMP-2 expression levels on the mRNA and protein level. RESULTS: Conventional PCR analysis could demonstrate the presence of MMP-2 mRNA in normal and osteoarthritic chondrocytes. Online quantitative PCR confirmed the presence of MMP-2 mRNA expression in normal articular chondrocytes in vivo (and in vitro). An increase of 5x (p < 0.001) was observed in osteoarthritic cartilage in vivo. Of note, no significant up-regulation of gelatinase A was observed by Il-1beta in vitro. Immunostaining for gelatinase A confirmed the presence of MMP-2 with mono- and polyclonal antibodies in normal and osteoarthritic chondrocytes with somewhat higher levels observed in the latter. CONCLUSIONS: The presented results confirm the increased expression of gelatinase A by osteoarthritic articular chondrocytes as previously described. Of note, also normal adult articular chondrocytes expressed significant amounts of gelatinase A in vivo and in vitro suggesting gelatinase A as being also involved in physiological collagen turnover in human adult articular cartilage.     

The efficacy of Brazilian black mud treatment in chronic experimental arthritis

Studies have demonstrated the beneficial effects of fangotherapy on relieve of pain improving function of rheumatic patients. Herein, we investigated the effect of Brazilian black mud in protect articular damage in chronic arthritis induced in rats. Mud was daily applied (40 degrees C/30 min) during the course of arthritis and was compared with warm water and no treated groups. At 21th day after arthritis induction synovial fluid and membrane were analyzed regarding cellular influx, hyperplasia and vascular proliferation. Cartilage structure, cell count, proteoglycan and collagen amount were also analyzed by three pathologists blinded to the treatment. Mud treatment diminished leukocyte migration into the synovial membrane and articular cavity when compared with both control groups. Regarding cartilage, an increase in collagen, number of chondrocytes and more conserved tissue structure was observed in mud-treated animals. These results demonstrate a protective effect of Brazilian mud on this model of arthritis, suggesting that this therapy may be useful as a complementary approach to treat articular diseases.     

Differential regulation of lubricin/superficial zone protein by transforming growth factor beta/bone morphogenetic protein superfamily members in articular chondrocytes and synoviocytes

OBJECTIVE: To investigate the role of transforming growth factor beta (TGFbeta)/bone morphogenetic protein (BMP) superfamily members on accumulation of superficial zone protein (SZP) in articular chondrocytes and synoviocytes. METHODS: Chondrocytes and synoviocytes were isolated from articular cartilage and synovium from calf stifle joints and cultured as monolayers in serum-free chemically defined medium. Articular chondrocytes were isolated from 3 distinct zones of the cartilage: superficial, middle, and deep. Accumulation of SZP in the culture medium in response to various members of the TGFbeta/BMP superfamily was demonstrated by immunoblotting and quantified by enzyme-linked immunosorbent assay. RESULTS: TGFbeta stimulated SZP accumulation in both superficial zone chondrocytes and synoviocytes. The 3 isoforms of TGFbeta elicited a similar dose response. Inhibition of TGFbeta receptor type I kinase by the specific inhibitor SB431542 abolished the TGFbeta-stimulated accumulation of SZP. BMPs up-regulated SZP accumulation in the superficial zone; however, the magnitude of the effects was not as great as was observed with TGFbeta. There was an additive action between TGFbeta and BMP on SZP accumulation. The response of synoviocytes to BMP was stronger than that of superficial zone chondrocytes. Activin up-regulated SZP accumulation in synoviocytes, but not in chondrocytes. CONCLUSION: TGFbeta is a critical regulator of SZP accumulation in both superficial zone articular chondrocytes and synoviocytes. TGFbeta and BMP have an additive effect. Synoviocytes are more sensitive to BMP family members and activins than are superficial zone articular chondrocytes. Thus, regulation of SZP accumulation by TGFbeta /BMP superfamily members is regulated differently in articular chondrocytes and synoviocytes.     

不同剂量T-2毒素对大鼠关节软骨损伤的形态学观察

目的 观察不同剂量T-2毒素对大鼠关节软骨的损害程度,探讨低剂量T-2毒素与大鼠关节软骨损伤的关系。方法 Wistar大鼠120只,体质量50～70 g。按体质量将大鼠随机分为4组：T-2毒素0（对照）、100、200、300 μg/kg组,每组30只。对照组食用常规颗粒料,T-2毒素组食用经T-2毒素(剂量分别为100、200、300 μg/kg)染毒的颗粒料。喂养6个月后处死大鼠,取双侧膝关节,制备切片,光镜和电镜下观察大鼠关节软骨的损伤情况。结果 光镜下,对照组大鼠关节软骨细胞群排列整齐,层次清晰,结构完好;100μg/kg 组关节软骨细胞排列紊乱;200μg/kg组关节软骨细胞出现变形、变性,细胞核固缩;300μg/kg组可见大面积的软骨细胞坏死,坏死部位细胞显著减少,呈现无细胞区,在坏死灶周围可见单个坏死软骨细胞,坏死细胞胞质红染、胞核浓缩、碎裂和溶解。扫描电镜下,对照组大鼠关节软骨细胞形态、结构良好,层次分明,排列整齐;100 μg/kg组关节软骨表面明显粗糙;200 μg/kg组软骨纤维凸起、断裂,呈片状剥脱;300μg/kg组关节面塌陷,出现大量窝状凹坑。透射电镜下,对照组大鼠软骨细胞胞质丰富,粗面内质网发达;100 μg/kg组软骨细胞核染色质块状边集,核膜增厚,内质网空泡变性;200 μg/kg组软骨细胞内质网扩张明显,蛋白潴留,细胞器溶解破裂;300μg/kg组软骨细胞细胞器大量溶解消失,膜结构破裂,基质溶解。结论 在100～300μg/kg剂量范围内,T-2毒素致大鼠关节软骨损伤与剂量有关,染毒剂量越大,关节软骨损害越严重。