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Cadmium is a well‐characterized nephrotoxic agent that is also capable of accumulating and diffusing across the placenta; however, only a few studies have addressed its effects over fetal kidneys and none of them has used a panel of sensitive and specific biomarkers for the detection of kidney injury. The goal of this study was to determine cadmium renal effects in rat fetuses by the quantification of early kidney injury biomarkers. Pregnant Wistar rats were exposed by inhalation to an isotonic saline solution or to CdCl2 solution (DDel=1.48 mg Cd kg?1 day?1) during gestational days (GD) 8–20. On GD 21, dams were euthanized and samples obtained. Kidney injury biomarkers were quantified in amniotic fluid samples and fetal kidneys were microscopically evaluated to search for histological alterations. Our results showed that cadmium exposure significantly raised albumin, osteopontin, vascular endothelial growth factor and tissue inhibitor of metalloproteinases‐1 levels in amniotic fluid, whereas it decreased creatinine. Clusterin, calbindin and IFN‐inducible protein 10 did not show any change. Accordingly, histological findings showed tubular damage and precipitations in the renal pelvis. In conclusion, gestational exposure to cadmium induces structural alterations in fetal renal tissue that can be detected by some kidney injury biomarkers in amniotic fluid samples. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
3.

Aim:

Wogonin (5,7-dihydroxy-8-methoxyflavone), a major bioactive compound of the flavonoid family, is commonly extracted from the traditional Chinese medicine Scutellaria baicalensis and possesses antioxidant and anti-inflammatory activities and is assumed to have anti-diabetes function. Indeed, a current study has shown that it can possibly treat metabolic disorders such as those found in db/db mice. However, the underlying molecular mechanism remains largely unclear. The aim of this study was to investigate the impact of wogonin on osteopontin (OPN) expression in adipose tissue from type 1 diabetic mice and in 3T3-L1 adipocytes.

Methods:

Type 1 diabetes was induced by streptozotocin (STZ) injection. 3T3-L1 preadipocytes were converted to 3T3-L1 adipocytes through treatment with insulin, dexamethasone, and 3-isobutyl-1-methylxanthine (IBMX). Western blot analysis and RT-PCR were performed to detect protein expression and mRNA levels, respectively.

Results:

Wogonin treatment suppressed the increase in serum OPN levels and reduced OPN expression in adipose tissue from STZ-induced type 1 diabetic mice. Administration of wogonin enhanced PPARα expression and activity. Silencing of PPARα diminished the inhibitory effects of wogonin on OPN expression in 3T3-L1 adipocytes. Furthermore, the levels of c-Fos and phosphorylated c-Jun were reduced in wogonin-treated adipose tissue and 3T3-L1 adipocytes. In addition, wogonin treatment dramatically mitigated p38 MAPK phosphorylation. Pharmacological inhibition of p38 MAPK by its specific inhibitor SB203580 increased PPARα activity and decreased OPN expression.

Conclusion:

Our results suggest that wogonin downregulated OPN expression in adipocytes through the inhibition of p38 MAPK and the sequential activation of the PPARα pathway. Given the adverse effects of high OPN levels on metabolism, our results provide evidence for the potential administration of wogonin as a treatment for diabetes.  相似文献   
4.
The correlation between calcification and papillary thyroid carcinoma has received increasing attention. We investigated the ability of bone sialoprotein (BSP) and osteopontin (OPN) protein levels to diagnose papillary thyroid carcinoma (PTC), and explored the correlation between BSP and OPN protein levels and calcification in PTC. Archival PTC specimens from patients with PTC with calcification and lateral cervical lymph node metastasis (LNM) were included in this retrospective immunohistochemical study. The protein levels of BSP and OPN were analysed immunohistochemically using routinely prepared tissue sections. PTC specimens from 66 patients with PTC were reviewed retrospectively (25 patients with histological calcification seen in paraffin sections, 41 patients without calcification; 35 patients with lateral cervical LNM, 31 patients without LNM). The percentage of samples that had cells that demonstrated positive protein staining differed significantly between PTC specimens, benign thyroid nodules, and adjacent normal follicular epithelium (BSP: 87.88%, 55.00%, and 42.50%, respectively; OPN: 83.33%, 70.00% and 50.00%, respectively). There was a significant difference in the immunohistochemical score (IHS) for BSP and OPN protein staining between PTC specimens with and without calcification (P < 0.05). The level of BSP protein staining was found to be significantly correlated with the level of OPN protein staining in PTC specimens. We conclude that the strong correlation between BSP and OPN and PTC suggests a role for BSP and OPN in calcification and tumor progression of PTC. BSP and OPN might be useful tumour markers for the diagnosis of PTC with limited value, because both of them had low specificity.  相似文献   
5.
We experienced a case of intraductal tubulopapillary neoplasms (ITPN) of the pancreas with severe calcification, which complicated image diagnosis. A pancreas head tumor was detected in a Japanese female in her 50s. Early enhancement by contrast‐enhanced CT and coarse calcification suggested a neuroendocrine tumor, although the obstruction and dilation of the main pancreatic duct appeared to be an intraductal tumor. An endoscopic ultrasound‐guided fine needle aspiration biopsy specimen revealed adenocarcinoma tissue. Pancreaticoduodenectomy was performed, and the patient has been well without evidence of recurrence for over 10 months. Pathological examination on the resected specimen revealed that the tumor showed papillary and tubulo‐cribriform growth patterns. Together with typical immunohistochemical results, the final diagnosis of ITPN was made. Characteristically, this case showed extensive calcification of both psammoma body‐type and non psammoma body‐type with foamy macrophage aggregation. This is the first report of ITPN with two types of calcification and macrophage. Since calcification might be one of the characteristic histological findings in ITPN as shown in our case, the possibility of ITPN should be also considered when calcification is detected in pancreatic lesions by various imaging modalities.  相似文献   
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近期相关研究提示,骨桥蛋白与心功能不全严重程度相关,其机制与介导细胞外基质表达,肾素-血管紧张素-醛固酮系统调控相关,有望作为心力衰竭患者临床评估的新的生物化学指标。本文就骨桥蛋白的结构、功能及其与心力衰竭相关的机制和意义进行综述。  相似文献   
8.
目的探讨内皮素-1(endothelin-1,ET-1)在糖尿病性勃起功能障碍(erectile dysfunction,ED)大鼠阴茎海绵体平滑肌细胞(corpus cavernosum smooth musclecells,CCSM)表型转化中的作用。方法采用链脲佐菌素建立糖尿病性ED大鼠模型,采用改良组织块贴壁法体外培养正常大鼠及糖尿病性ED大鼠CCSM,将CCSM分为对照组、糖尿病性ED组、对照+ET-1组和糖尿病性ED+ET-1组,其中对照+ET-1组与糖尿病性ED+ET-1组加入10^-7mol/LET-1,对照组与糖尿病性ED组加入PBS缓冲液。采用RT—PCR法检测4组碱性调宁蛋白(calponin 1,Cnnl)和骨桥蛋白(osteopontin,OPN)mRNA表达情况。结果糖尿病性ED+ET-1组CnnlmRNA表达水平(3.51±0.15)低于对照组(10.21±1.52)和糖尿病性ED组(4.79±0.56),糖尿病性ED组和对照+ET-1组(5.04±0.64)低于对照组(P〈0.01);糖尿病性ED+ET-1组OPNmRNA表达水平(6.97±0.74)高于对照组(1.22±0.21)和糖尿病ED组(5.35±0.62),糖尿病性ED组和对照+ET-1组(4.98±0.46)高于对照组(P〈O.01)。结论ET-1不仅对收缩型CCMS有促表型转化作用,对合成型CCMS也有促表型转化作用,且ET-1对CCSM的作用是不可逆的。  相似文献   
9.
目的探讨绝经后妇女循环骨桥蛋白(OPN)水平与骨转换和骨密度(BMD)之间的关系。方法 2015年7月至2017年8月,共有287名绝经后妇女纳入本研究。分析血清OPN水平,核因子κB(NF-κB)配体受体激活剂(RANKL)和骨转换标志物。采用双能X线吸收仪测定BMD。结果根据世界卫生组织(WHO)标准,102名受试者(35.5%)被诊断为骨质疏松症,125名(43.6%)骨质减少,60名(20.9%)正常骨密度。骨质疏松组的OPN水平显著高于骨量减少组和正常组(均为P0.001)。OPN诊断绝经后骨质疏松症的临界值为10.2 ng/mL,敏感性为90.1%,特异性为56.8%,曲线下面积为0.949。血清OPN和骨质疏松症组中甲状旁腺激素(PTH),腰椎BMD和股骨颈骨密度呈负相关,与I型前胶原氨基端前肽(PINP),I型的羧基端交联端肽胶原(CTX)和RANKL呈正相关。在多元回归分析中,腰椎骨密度,PTH和RANKL可以作为血清OPN水平的预测指标。结论 OPN血清水平与BMD呈负相关,与中国绝经后妇女骨转换水平呈正相关。  相似文献   
10.
目的探讨骨桥蛋白(OPN)、血管内皮生长因子-A(VEGF—A)和乏氧诱导因子(HIF)-1α在肝细胞癌(HCC)中的表达及临床意义。方法采用免疫组织化学法检测肝癌组(90例)、癌旁肝硬化组(20例)及正常组(15例)中OPN、VEGF—A和HIF-1α的表达。结果OPN、VEGF—A和HIF-1α在HCC组呈明显高表达,阳性率分别为76.67%(69/90)、71.11%(64/90)和73.33%(66/90)。其中OPN、VEGF—A显著高于癌旁肝硬化组及正常组,HIF-1α在HCC组的表达与肝硬化组无差异,与正常组有显著差异。OPN、VEGF—A、HIF—1α的表达与肝癌的临床病理特征如癌栓形成、包膜完整性、肿瘤分化和分期、肿瘤转移等有相关性(P〈0.05),三者之间表达呈正相关性(P〈0.05)。结论OPN、VEGF—A、HIF-1α在肝癌中高表达,联合检测有助于判断肝癌的生物学特征,为肝癌的分子靶向治疗提供重要的可能靶点。  相似文献   
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