葛根素减轻部分由过氧亚硝基阴离子导致的糖尿病大鼠晶状体上皮细胞凋亡

本研究观察葛根素是否减轻部分由过氧亚硝基阴离子（peroxynitrite,ONOO^-）导致的糖尿病大鼠晶状体上皮细胞（lens epithelium cell,LEC）凋亡。采用大鼠腹腔注射链脲佐菌素（streptozotocin,STZ）的方法建立糖尿病动物模型。36只大鼠作为对照组,腹腔注射生理盐水;其他72只大鼠腹腔注射STZ（45mg/kg）后分为STZ组和STZ＋葛根素组,每组36只。STZ注射3d后,STZ＋葛根素组大鼠每天腹腔注射葛根素（140mg／kg）。于实验开始后第20、40和60天用裂隙灯检查晶状体的形态学变化后处死动物。用流式细胞仪检测LEC凋亡,用免疫组化方法检测晶状体中ONOO^-的标志物——硝基酪氨酸（nitrotyrosine,NT）的表达,用基因芯片分析技术检测LEC凋亡相关基因iNOS等的表达。结果发现,对照组大鼠晶状体均透明,各项指标基本正常;STZ组大鼠第20天时即出现晶状体混浊,40-60d期间混浊不断加重;STZ＋葛根素组大鼠20-40d时晶状体混浊呈加重趋势,但40-60d以后明显减轻。对照组LEC轻度凋亡,而STZ组凋亡细胞呈持续性增长,STZ＋葛根素组大鼠20-40d时细胞凋亡呈增长趋势,但40-60d以后明显下降。对照组大鼠晶状体NT未见明显表达;STZ组大鼠NT表达明显加强;STZ＋葛根素组大鼠20-40d时NT表达呈增长趋势,但40-60d以后明显下降。对照组凋亡相关基因未见明显变化,STZ组凋亡相关基因iNOS表达明显上调。其他凋亡相关基因如BCL-2、SOD表达明显下调,但NF-κB和TNFR1-FADD-caspase信号转导途径明显上调;STZ＋葛根素组凋亡相关基因表达则呈相反改变。上述结果表明,在糖尿病大鼠晶状体中有ONOO^-的标志物NT表达,证明糖尿病大鼠LEC凋亡部分由ONOO^-诱导,这可能是氧化损伤导致白内障形成的新途径。葛根素能够部分逆转ONOO^-对LEC的致凋亡作用,提示葛根素可能是治疗糖尿病性白内障的有效药物,其治疗机制可能与葛根素直接抑制凋亡和对抗ONOO^-对糖尿病大鼠LEC的损伤有关。     

Evaluation of the Fas/FasL signaling pathway in diabetic rat testis

We investigated the role of the Fas/Fas ligand (FasL) signaling pathway in diabetic male infertility. Male rats were divided into two groups: a control group and a streptozotocin induced diabetic group. Thirty days after induction of diabetes, samples of testes were harvested and fixed in 10% formalin for light microscopy. Germ cell apoptosis was determined using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate in situ nick end-labeling (TUNEL) and immunostaining of caspase 8 and active caspase 3. We also investigated the expressions of Fas and FasL using immunohistochemistry. Streptozotocin-induced diabetes caused severe histopathological damage and increased apoptotic tubule and apoptotic cell indices, caspase 8 and caspase 3 expressions, and Fas and FasL-immunopositive cells in the rat testes. We suggest that the Fas/FasL signaling pathway may play a role in male infertility caused by diabetes.     

葛根素对糖尿病心肌细胞的保护及其机制研究

观察葛根素（Puerarin）对链脲佐菌素（streptozotocin,STZ）诱导的糖尿病大鼠心肌细胞的保护作用,并探讨血小板反应素1（Thrombospondin-1,TSP-1）的表达改变及其作用。雄性SD大鼠45只随机分为三组（n=15）：糖尿病组和葛根素治疗组采用一次腹腔注射链脲佐菌素（STZ）65mg／kg制备糖尿病模型,其中葛根素治疗组于造模后葛根素腹腔注射4周（100mg/kg/day）,正常对照组仅腹腔注射等量生理盐水（6ml／kg）,同样喂养4周。四周后各组大鼠处死。H—E染色及透射电子显微镜观察三组大鼠心肌细胞纤维显微结构和超微结构的病理改变．免疫组化和实时荧光定量PCR法观察大鼠心肌细胞中TSP-1蛋白和mRNA表达的变化．同时利用Langendorff离体心脏灌流法测定各组大鼠心室肌细胞功能。结果发现葛根素治疗组较糖尿病组大鼠的体重增加明显,同时血糖下降,有显著性差异（P〈0．01）。H—E染色显示糖尿病大鼠多处心肌肌丝紊乱伴少量炎症细胞浸润,电镜下发现有线粒体嵴消失溶解,肌丝排列紊乱等病理改变,而葛根素治疗组大鼠偶见上述病理变化。免疫组化显示葛根素治疗组心肌内TSP-1阳性细胞密度小于糖尿病大鼠,TSP-1 mRNA表达也比糖尿病大鼠要低。此外葛根素治疗组大鼠的左室收缩末压（LVSEP）、左心室舒张末期压（LVEDP）等心功能指标均明显低于正常组（P〈0．01）,但较糖尿病组有显著改善（P〈0．01）。上述结果显示葛根素能保护糖尿病大鼠心肌细胞的高糖损伤和维持心室肌细胞的功能,而该机制可能与抑制心肌细胞TSP-1表达的水平有关。     

Allicin protects against myocardial apoptosis and fibrosis in streptozotocin-induced diabetic rats

To evaluate the cardioprotective effect of allicin (AL) on myocardial injury of streptozotocin (STZ)-induced diabetic rats and to further explore its underlying mechanisms. Hyperglycemia was induced in rats by single intraperitoneal injection of STZ (40 mg/kg). Three days after STZ induction, the hyperglycemic rats (plasma glucose levels ≥ 16.7 mmol/l) were treated with AL by intraperitoneal injection at the doses of 4 mg/kg, 8 mg/kg, and 16 mg/kg daily for 28 days. The fasting blood glucose levels were measured on every 7th day during the 28 days of treatment. The body weight, blood glucose, and parameter of cardiac function were detected after 4 weeks to study the cardioprotective effects of AL on diabetic rats in vivo. The apoptotic index of cardiomyocytes was estimated by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The expressions of Fas, Bcl-2, CTGF, and TGF-β(1) protein were studied by immunohistochemistry. Laser scanning confocal microscopy technique was utilized to observe the effects of AL on intracellular calcium concentration ([Ca(2+)](i)) in rat ventricular cardiomyocytes. AL at the doses of 4 mg/kg, 8 mg/kg, and 16 mg/kg significantly reduced blood glucose levels in a dose-dependent manner and increased body weight as well compared with the model group. Hemodynamic parameters including left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), and maximum rate of left ventricular pressure rise and fall (+dp/dtmax and -dp/dtmax) were significantly restored back to normal levels in AL-treated (8 mg/kg and 16 mg/kg) rats compared with diabetic model rats. AL markedly inhibited cardiomyocyte apoptosis induced by diabetic cardiac injury. Further investigation revealed that this inhibitory effect on cell apoptosis was mediated by increasing anti-apoptotic protein Bcl-2 and decreasing pro-apoptotic protein Fas. Additional experiments demonstrated AL abrogated myocardial fibrosis by blocking the expressions of CTGF and TGF-β(1) protein. AL shows protective action on myocardial injury in diabetic rats. The possible mechanisms were involved in reducing blood glucose, correcting hemodynamic impairment, reducing Fas expression, activating Bcl-2 expression, decreasing intracellular calcium overload, inhibiting the expressions of TGF-β(1) and CTGF, and further improving cardiac function.     

Requirement of the Fas ligand-expressing luteal immune cells for regression of corpus luteum

Apoptosis in corpus luteum (CL) is induced by prolactin (PRL) in female rats. PRL-induced apoptosis in CL is mediated by the Fas/Fas ligand (FasL) system. The CL consists of steroidogenic and non-steroidogenic cells, including immunocytes. Fas mRNA was detected only in the luteal steroidogenic cells, and FasL mRNA was expressed only by the non-steroidogenic CD3-positive luteal immunocytes. Removing the luteal immune cells from the luteal cells inhibited PRL-induced luteal cell apoptosis effectively. Thus, FasL-expressing non-steroidogenic luteal immunocytes are required for PRL-induced luteal cell apoptosis and heterogeneous induction of apoptosis by Fas/FasL in CL.     

肢体缺血-再灌注大鼠脑组织iNOS基因表达的半定量检测

目的检测大鼠肢体缺血-再灌注后脑组织iNOS基因表达的变化.方法SD大鼠,随机分为肢体缺血-再灌注(I-R)组、肢体单纯缺血(I)组及正常对照(N)组,通过夹闭腹主动脉末端4?h,或/和开放2～24?h,复制I、I-R组动物模型,半定量RT-PCR方法检测脑组织iNOSmRNA表达的变化,免疫组化染色法观测脑组织内iNOS及过氧亚硝基阴离子(ONOO-)的硝基化产物硝基酪氨酸(NT)的生成与分布.结果N组脑组织iNOSmRNA未检出,I组及I-R组脑组织iNOSmRNA均有表达,再灌注2?h,iNOSmRNA表达量显著升高(P<0.01,vsN组),再灌注6?h达到高峰,随后下降,24?h仍有少量表达;I及I-R组脑组织均有iNOS阳性细胞,I-R组见于大脑皮层各区、海马、尾状核,I组仅见于皮层后肢区及尾状核.I-R组脑组织可见弥散分布的NT阳性神经元,I组偶见NT阳性神经元.结论大鼠肢体缺血-再灌后脑组织iNOS基因表达显著增强,且有时相变化特征.     

夏枯草胶囊对自身免疫性甲状腺炎大鼠甲状腺组织及Fas、FasL表达的影响

目的:探讨夏枯草胶囊对自身免疫性甲状腺炎(AITD)大鼠甲状腺组织病理学及Fas、FasL表达的影响。方法:将40只雌性SD大鼠按照随机数表法随机分为空白对照组、模型组、夏枯草胶囊组、硒酵母组,每组10只,空白对照组予以正常饲养,模型组和药物组予以PTg皮下注射建立AITD模型,夏枯草胶囊组、硒酵母组分别给予夏枯草胶囊与硒酵母片的生理水溶液灌胃,药物干预6周后处死大鼠,取甲状腺组织,HE染色电镜下观察各组大鼠甲状腺组织形态,免疫组化法检测各组大鼠甲状腺组织Fas、FasL蛋白的表达。结果:1)模型组大鼠甲状腺组织滤泡大量破坏,形态不规则,胶质分布不均匀,滤泡间隙增大,可见大量淋巴细胞及浆细胞浸润。夏枯草胶囊组滤泡形态尚规则,胶质含量较空白组少,滤泡间有少量淋巴细胞浸润。与模型组对比,夏枯草胶囊组与硒酵母组滤泡破坏及淋巴细胞浸润有显著改善。2)对照组大鼠甲状腺组织中Fas、FasL蛋白仅呈少量表达,模型组大鼠甲状腺组织中Fas、FasL蛋白表达较对照组显著增加(P0.01),夏枯草胶囊组大鼠甲状腺组织中Fas、FasL蛋白表达较模型组及硒酵母组均显著减少(P0.01)。结论:夏枯草胶囊可能通过减少Fas、FasL的表达,抑制甲状腺滤泡细胞凋亡,从而减轻甲状腺滤泡上皮的破坏。     

Advanced glycation end-product (AGE) induces apoptosis in human retinal ARPE-19 cells via promoting mitochondrial dysfunction and activating the Fas-FasL signaling

Advanced glycation end-products (AGEs) are extremely accumulated in the retinal vascular and epithelial cells of diabetes mellitus (DM) patients, particularly with diabetic retinopathy (DR). To elucidate the pathogenesis of the AGE-induced toxicity to retinal epithelial cells, we investigated the role of Fas–Fas ligand (FasL) signaling and mitochondrial dysfunction in the AGE-induced apoptosis. Results demonstrated that the AGE-BSA- induced apoptosis of retinal ARPE-19 cells. And the AGE-BSA treatment caused mitochondrial dysfunction, via deregulating the B-cell lymphoma 2 (Bcl-2) signaling. Moreover, the Fas/FasL and its downstreamer Caspase 8 were promoted by the AGE-BSA treatment, and the exogenous α-Fas exacerbated the activation of Caspase 3/8. On the other side, the siRNA-mediated knockdown of Fas/FasL inhibited the AGE-BSA-induced apoptosis. Taken together, we confirmed the activation of Fas–FasL signaling and of mitochondrial dysfunction in the AGE-BSA-promoted apoptosis in retinal ARPE-19 cells, implying the important role of Fas–FasL signaling in the DR in DM.     

Decreased neutrophil adhesion to human cytomegalovirus-infected retinal pigment epithelial cells is mediated by virus-induced up-regulation of Fas ligand independent of neutrophil apoptosis

Human CMV (HCMV) retinitis frequently leads to blindness in iatrogenically immunosuppressed patients and in the end stage of AIDS. Despite the general proinflammatory potential of HCMV, virus infection is associated with a rather mild cellular inflammatory response in the retina. To investigate this phenomenon, the influence of HCMV (strains AD169 or Hi91) infection on C-X-C chemokine secretion, ICAM-1 expression, and neutrophil recruitment in cultured human retinal pigment epithelial (RPE) cells was studied. Supernatants from infected cultures contained enhanced levels of IL-8 and melanoma growth-stimulating activity/Gro alpha and induced neutrophil chemotaxis compared with supernatants from uninfected RPE cells. Despite HCMV-induced ICAM-1 expression on RPE cells, binding of activated neutrophils to HCMV-infected RPE cells and subsequent transepithelial penetration were significantly reduced. Reduced neutrophil adhesion to infected RPE cells correlated with HCMV-induced up-regulation of constitutive Fas ligand (FasL) expression. Functional blocking of FasL on RPE cells with the neutralizing mAbs NOK-1 and NOK-2 or of the Fas receptor on neutrophils with mAbB-D29 prevented the HCMV-induced impairment of neutrophil/RPE interactions. Fas-FasL-dependent impairment of neutrophil binding had occurred by 10 min after neutrophil/RPE coculture without apoptotic signs. Neutrophil apoptosis was first detected after 4 h. Treatment of neutrophils with a specific inhibitor of caspase-8 suppressed apoptosis, whereas it did not prevent impaired neutrophil binding to infected RPE. The current results suggest a novel role for FasL in the RPE regulation of neutrophil binding. This may be an important feature of virus escape mechanisms and for sustaining the immune-privileged character of the retina during HCMV ocular infection.     

Progesterone is a cell death suppressor that downregulates Fas expression in rat corpus luteum

In female rats, apoptotic cell death in the corpus luteum is induced by the prolactin (PRL) surge occurring in the proestrous afternoon during the estrous cycle. We have previously shown that this luteolytic action of PRL is mediated by the Fas/Fas ligand (FasL) system. During pregnancy or pseudopregnancy, apoptosis does not occur in the corpus luteum. Progesterone (P4), a steroid hormone secreted from luteal steroidogenic cells, attenuated PRL-induced apoptosis in cultured luteal cells in a dose-dependent manner. P4 significantly decreased the expression of mRNA of Fas, but not FasL, in cultured luteal cells prepared from both proestrous and mid-pseudopregnant rats. These data indicate that P4 suppresses PRL-induced luteal cell apoptosis via reduction of the expression level of Fas mRNA in the corpus luteum, suggesting that P4 acts as an important factor that can change the sensitivity of corpus luteum to PRL.     

锌和维生素E对Ⅰ型糖尿病大鼠心肌的保护作用

目的探讨锌（Zn）和维生素E（VE）对糖尿病大鼠心肌细胞保护作用的机制。方法按体重将大鼠随机分为正常对照组（10只）和实验组（40只）,实验组动物采用腹腔注射链脲左菌素（streptozotocin,STZ）,60mg/kg一次注射,制备糖尿病大鼠模型。将40只按血糖值参考体重分为4组：糖尿病对照组,糖尿病补锌组,糖尿病补VE组,糖尿病补Zn＋VE组。6周后将各组大鼠处死,切取心室肌组织,进行免疫组织化学染色,观察各组心肌组织NF-κB和i NOS的表达水平,利用HPIAS-2000图像分析系统测定核转录因子（nuclear factor-kappa B,NF-κB）和诱导型一氧化氮合酶（i NOS）在以上各组中表达的平均光密度和平均阳性面积率。结果正常对照组心肌细胞内NF-κB和i NOS呈阴性表达,糖尿病对照组心肌细胞内NF-κB和i NOS呈阳性表达;糖尿病补锌组和糖尿病补VE组心肌细胞内NF-κB和i NOS呈弱阳性表达;糖尿病补Zn＋VE组心肌细胞内NF-κB和i NOS呈阴性表达。图像分析结果显示：糖尿病补Zn＋VE组与糖尿病对照组、糖尿病补锌组及糖尿病补VE组之间NF-κB和i NOS的平均光密度及阳性面积率的差异有显著性意义（P〈0.05）;糖尿病补Zn＋VE组与正常组之间NF-κB和i NOS的平均光密度及阳性面积率的差异无显著性意义（P〉005）。结论Zn和VE联合使用可降低糖尿病大鼠心肌组织中NF-κB和i NOS的活性,对糖尿病大鼠心肌细胞具有保护作用。     

在HBV感染的肝癌组织中Fas/FasL表达的作用

目的探讨Fas／FasL（Fas配体）在原发性肝细胞肝癌（HCC）组织中的表达及其与乙肝病毒（HBV）感染的关系。方法用免疫组化S-P法检测21例肝癌组织及其10例癌旁组织Fas／FasL的表达。结果在肝癌和癌旁组织中Fas表达的阳性率分别为52．38％和80．00％（P〈0．05）,FasL分别为66．67％和40．00％（P〈0．05）。在HBsAg阳性和阴性组Fas表达的阳性率分别为50．00％和66．67％（P〉0．05）;FasL分别为61．11％和100％（P〈0．05）。肝癌组织中Fas、FasL表达与性别、年龄、肿瘤大小无关,与癌栓转移呈负相关,FasL与分化程度有关。结论肝癌细胞能下调Fas及上调FasL的表达而使凋亡受阻,HBV感染能抑制肝癌组织FasL的表达,可能是HBV在HCC的发牛及发展讨稃中的致痛机制。     

壮肝逐瘀煎对肝纤维化大鼠肝脏Fas/FasL表达的影响

目的:研究壮肝逐瘀煎对肝纤维化(HF)大鼠肝脏肝星状细胞(HSC)的凋亡因子Fas/FasL表达的影响,探讨该方抗HF的作用机制。方法:58只SD大鼠随机取14只作为正常对照组,正常饲养。剩余大鼠采用CCl4复合因素法进行HF造模,实验第4周末随机处死造模大鼠4只,证实HF形成。其余随机分为病理模型组、壮肝逐瘀煎组、秋水仙碱组及大黄蛰虫丸组,每组10只。病理模型组给予生理盐水灌胃处理,其他3组分别予对应药物灌胃处理。治疗第6周末,处死所有大鼠,获取肝组织,HE染色光镜观察肝组织结构变化,免疫组化染色分析Fas、FasL分布。结果:与病理模型组大鼠比较,壮肝逐瘀煎治疗组肝小叶结构趋于正常,纤维间隔明显变薄,肝组织Fas、FasL的表达显著表达显著减少(P0.01)。结论:壮肝逐瘀煎能够明显改善HF大鼠肝脏的病理变化,具有明显的抗HF作用,其作用机制可能与壮肝逐瘀煎能调控HSC中凋亡因子Fas/FasL的表达有关。     

Inhibitor of apoptosis proteins and ovarian dysfunction in galactosemic rats

Galactosemia is a genetic disease with deficiency of galactose-1-uridyltransferase, resulting in the accumulation of galactose or galactose-1-phosphate in the blood and tissues. Rats were fed with normal rat chow and with a high-galactose diet for 4 weeks to give control and galactosemic groups, and their ovarian function was studied. The two groups of rats were injected with pregnant mare's serum gonadotrophin (PMSG) and were killed at different time points after human chorionic gonadotrophin (hCG) injection. The number of oocytes ovulated in the controls was significantly higher than in the galactosemic group. Morphometric studies of the ovaries also showed a higher number of corpora lutea in the controls. Western blot analysis of granulosa cells showed that the overall expressions of Fas and FasL were lower in the control group and their expressions of inhibitor of apoptosis proteins (IAPs) were higher than in the galactosemic group, especially at 8 h post hCG injection. TDT-mediated dUTP-biotin nick end-labeling (TUNEL) and immunohistochemical staining of ovarian sections with Ki-67 and IAPs showed more apoptotic granulosa cells in the galactosemic group and the expressions of IAPs in granulosa cells also confirmed the result of the Western blot. These findings support our hypothesis that ovarian dysfunction in galactosemic rats is due to increased apoptosis in granulosa cells of maturing follicles.     

Localization of glycogen in the placenta and fetal and maternal livers of cadmium-exposed diabetic pregnant rats

This study was designed to investigate the effects of Cd exposure on the glycogen localization in the placenta and in fetal and maternal livers in streptozotocin (STZ)-induced-diabetic pregnant rats. Ninety-nine virgin female Wistar rats (200–220 g) were mated with 33 males for at least 12 h. From the onset of pregnancy, the rats were divided into four experimental groups (control, Cd treated, STZ treated, and Cd+STZ treated). The Cd-treated group was injected subcutaneously daily with CdCl₂ dissolved in isotonic NaCl, starting at the onset of pregnancy throughout the experiment. Diabetes was induced on d 13 of pregnancy by a single intraperitoneal injection of STZ in the STZ-treated group. In addition to the daily injection of Cd, a single intraperitoneal injection of STZ was also given on d 13 of pregnancy in the Cd+STZ-treated group. The rats received the last injection 24 h before being sacrificed and 10 randomly selected rats in each group were sacrificed on d 15 and d 20 of pregnancy. Blood samples were taken for determination of the serum glucose and insulin levels. Fetal and maternal livers of sacrificed rats in all groups were harvested on d 15 and d 20 of pregnancy, whereas placentas were harvested only on d 20 of pregnancy for histochemical examination. Although both Cd and STZ caused hyperglycemia and decreased insulin secretion, Cd-alone treatment increased the glycogen content only in the placental labyrinth, whereas STZ-alone treatment increased the glycogen content only in the maternal part of the placenta. Increased glycogen localization was observed in both the placental labyrinth and the maternal part of placenta when Cd and STZ were given together. Fetal and meternal livers of control and other treatment groups were not different regarding the glycogen content on d 15 or d 20 of pregnancy. It was concluded that Cd exposure during pregnancy might produce a glycogen localization in the placenta of diabetic rats. However, the function and the mechanisms of increased glycogen contents in the placenta of Cd-exposed pregnant diabetic rats remain unclear and further studies are needed.     

Fas ligand expression coincides with alveolar cell apoptosis in late-gestation fetal lung development

Apoptosis plays a central role in the cellular remodeling of the developing lung. We determined the spatiotemporal patterns of the cell death regulators Fas and Fas ligand (FasL) during rabbit lung development and correlated their expression with pulmonary and type II cell apoptosis. Fetal rabbit lungs (25-31 days gestation) were assayed for apoptotic activity by terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL) and DNA size analysis. Fas and FasL expression were analyzed by RT-PCR, immunoblot, and immunohistochemistry. Type II cell apoptosis increased significantly on gestational day 28; the type II cell apoptotic index increased from 0.54 +/- 0.34% on gestational day 27 to 3.34 +/- 1.24% on day 28, P < 0.01 (ANOVA). This corresponded with the transition from the canalicular to the terminal sac stage of development. The day 28 rise in epithelial apoptosis was synchronous with a robust if transient 20-fold increase in FasL mRNA and a threefold increase in FasL protein levels. In contrast, Fas mRNA levels remained constant, suggestive of constitutive expression. Fas and FasL proteins were immunolocalized to alveolar type II cells and bronchiolar Clara cells. The correlation of this highly specific pattern of FasL expression with alveolar epithelial apoptosis and remodeling implicates the Fas/FasL system as a potentially important regulatory pathway in the control of postcanalicular alveolar cytodifferentiation.     

骨形态发生蛋白-7及抑制性Smads在糖尿病肾病发生发展中的表达变化

本文采用免疫组化、Western blot及荧光实时定量PCR方法,动态观察链脲佐菌素（streptozocin,STZ）诱导的大鼠糖尿病肾病（diabetic nephropathy,DN）发生早期肾脏骨形态发生蛋白-7（bone morphogenetic protein-7,BMP-7）、Smad6、Smad7蛋白及mRNA表达。结果显示,在正常及DN大鼠肾小管均有BMP-7、Smad6、Smad7蛋白表达,以胞浆表达为主。DN大鼠BMP-7、Smad6蛋白表达较正常大鼠明显增多（P〈0．05）,且BMP-7的mRNA表达呈先增加后降低的状态;而Smad7蛋白和mRNA的表达均呈先增加后降低的状态。转化生长因子-β1（transforming growth factor-β1,TGF-β1）及Ⅰ型胶原（collagen typeⅠ,COL-Ⅰ）mRNA在DN大鼠肾脏表达较正常大鼠明显增多（P〈0．05）,且随着糖尿病进展有逐渐增加的趋势。结果提示,作为TGF-β超家族信号分子的一员,BMP-7信号及抑制性Smad通路在DN肾纤维化发生早期可能起重要的反馈性抑制作用。     

硫化氢对1型糖尿病大鼠膈肌NO含量和iNOS活性的影响

目的：观察硫化氢（H2S）对1型糖尿病大鼠膈肌一氧化氮（NO）含量和诱导型一氧化氮合酶（iNOS）活性的影响。方法：将32只雄性SD大鼠随机分为4组：正常组（NC组）、糖尿病组（DM组）、糖尿病治疗组（DM + NaHS组）和NaHS对照组（NaHS组）（n=8）。采用一次性腹腔注射链脲佐菌素55 mg/kg制备1型糖尿病大鼠模型,造模成功后第4周起,DM + NaHS组和NaHS组大鼠腹腔注射NaHS溶液14μmol/kg干预治疗。连续注射5周后,测大鼠空腹血糖值（FBG）和膈肌重量/体重量比（DW/BW）;HE染色观察膈肌显微结构变化;利用NOS分型测试盒测膈肌组织iNOS活性;硝酸还原法测定膈肌组织NO含量;利用RT-PCR和Western blot分别检测膈肌组织iNOS mRNA和蛋白表达。结果：与NC组比较,DM组大鼠FBG显著升高,膈肌显微结构损伤明显,DW/BW下降,膈肌组织iNOS活性和NO含量显著增加,iNOS mRNA和蛋白表达明显增高,NaHS组各项指标差异无统计学意义。与DM组比较,DM + NaHS组膈肌显微结构明显改善,DW/BW增高,膈肌组织iNOS活性和NO含量明显下降,iNOS mRNA和蛋白表达显著降低。结论：外源性补充H2S可能通过下调膈肌组织iNOS活性和蛋白表达,降低NO含量,进而保护糖尿病大鼠膈肌的功能。