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51.
This project assesses the treatment role with insulin and (or) angiotensin II receptor subtype-1 (AT1-R) blocker (ARB) on insulin receptor and endothelin-1 receptor subtype (ETA-R and ETB-R) regulation in rat hearts suffering from insulin-dependent diabetes mellitus (IDDM). Animals were divided into 6 groups: groups 1, 3, and 5 were controls consisting of normal, diabetic (streptozotocin-treated, once at 0 time), and diabetic supplemented daily with insulin, respectively, whereas groups 2, 4, and 6 were the controls treated daily with losartan. One month after enrollment, rats were sacrificed and samples of cardiac tissue were snapped frozen for immunostaining and Western blotting. Insulin receptor density was observed to be upregulated in the cardiomyocytes of diabetic animals, but downregulated with insulin supplementation alone. Cotreatment with insulin and an ARB resulted in drastic increase in insulin-receptor density in the diabetic rats. In addition, expression of ETA-R in cardiomyocytes was upregulated and was consistently maintained within the various treatment modalities. However, ETB-R expression was significantly reduced in the diabetic group treated with both insulin and an ARB. The changes in the expression of the insulin, the ETA-Rs, and the ETB-Rs at the various sites of the myocardium and the effect of both insulin treatment and blockade of the AT1-R explain the new benefits related to the halting of myocardial remodeling in IDDM rats.  相似文献   
52.
Ecballium elaterium, a medicinal plant, whose fruit juice is used for the treatment of jaundice in folk medicine, has been reported as being capable of decreasing bilirubinemia in animals with jaundice [H.H. Elayan, M.N. Garaibeh, S.M. Zmeili, S.A. Salhab, Effects of Ecballium elaterium juice on serum bilirubin concentration in male rats, Int. J. Crude Drug Res. 27 (1989) 227-234]. The aim of this study is to identify the Ecballium elaterium components, which are able to modify the binding of bilirubin to albumin. The juice is fiber-free but contains proteins, lipids, sugars, and minerals. The extract of the juice, analyzed by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), contains cucurbitacins (Cuc) B, D, E, and I as well as several glycosylated compounds. Human plasma containing no or serial concentrations of Ecballium elaterium components were prepared and the direct bilirubin (DB) and total bilirubin (TB) were determined by the Jendrassik and Grof method. Our results showed that Cuc D, E, and B decreased the levels of DB and TB in plasma, while Cuc I, glycosyl derivatives, and proteins of the juice did not modify the bilirubin levels. The binding of domain specific ligands to HSA, bilirubin (domain IIA), and ibuprofen (domain IIIA), were studied in the absence and presence of Cuc D, E, and I, by fluorescence spectroscopy. The values of binding constant K(a) and binding site number n, determined by Scatchard method, increased for the both ligands only in the presence of Cuc E and D. Cuc I decreased slightly the K(a) of ibuprofen, suggesting an interaction with the domain IIIA of the protein. As a conclusion, Cuc E, D, and B produce rearrangement in the structure of albumin leading to increase the binding of domain specific ligands, ibuprofen and bilirubin.  相似文献   
53.
54.
Osteoactivin promotes breast cancer metastasis to bone   总被引:1,自引:0,他引:1  
The skeleton is a preferred site of metastasis in patients with disseminated breast cancer. We have used 4T1 mouse mammary carcinoma cells, which metastasize to bone from the mammary fat pads of immunocompetent mice, to identify novel genes involved in this process. In vivo selection of parental cells resulted in the isolation of independent, aggressively bone metastatic breast cancer populations with reduced metastasis to the lung. Gene expression profiling identified osteoactivin as a candidate that is highly and selectively expressed in aggressively bone metastatic breast cancer cells. These cells displayed enhanced migratory and invasive characteristics in vitro, the latter requiring sustained osteoactivin expression. Osteoactivin depletion in these cells, by small interfering RNA, also lead to a loss of matrix metalloproteinase-3 expression, whereas forced osteoactivin expression in parental 4T1 cells was sufficient to elevate matrix metalloproteinase-3 levels, suggesting that this matrix metalloproteinase may be an important mediator of osteoactivin function. Overexpression of osteoactivin in an independent, weakly bone metastatic breast cancer cell model significantly enhanced the formation of osteolytic bone metastases in vivo. Finally, high levels of osteoactivin expression in primary human breast cancers correlate with estrogen receptor-negative status and increasing tumor grade. Thus, we have identified osteoactivin as a protein that is expressed in aggressive human breast cancers and is capable of promoting breast cancer metastasis to bone.  相似文献   
55.
Helicobacter pylori (H. pylori) causes gastric mucosa inflammation and gastric cancer mostly via several virulence factors. Induction of proinflammatory pathways plays a crucial role in chronic inflammation, gastric carcinoma, and H. pylori pathogenesis. Herbal medicines (HMs) are nontoxic, inexpensive, and mostly anti-inflammatory reminding meticulous emphasis on the elimination of H. pylori and gastric cancer. Several HM has exerted paramount anti-H. pylori traits. In addition, they exert anti-inflammatory effects through several cellular circuits such as inhibition of 5′-adenosine monophosphate-activated protein kinase, nuclear factor-κB, and activator protein-1 pathway activation leading to the inhibition of proinflammatory cytokines (interleukin 1α [IL-1α], IL-1β, IL-6, IL-8, IL-12, interferon γ, and tumor necrosis factor-α) expression. Furthermore, they inhibit nitrous oxide release and COX-2 and iNOS activity. The apoptosis induction in Th1 and Th17-polarized lymphocytes and M2-macrophagic polarization and STAT6 activation has also been exhibited. Thus, their exact consumable amount has not been revealed, and clinical trials are needed to achieve optimal concentration and their pharmacokinetics. In the aspect of bioavailability, solubility, absorption, and metabolism of herbal compounds, nanocarriers such as poly lactideco-glycolide-based loading and related formulations are helpful. Noticeably, combined therapies accompanied by probiotics can also be examined for better clearance of gastric mucosa. In addition, downregulation of inflammatory microRNAs (miRNAs) by HMs and upregulation of those anti-inflammatory miRNAs is proposed to protect the gastric mucosa. Thus there is anticipation that in near future HM-based formulations and proper delivery systems are possibly applicable against gastric cancer or other ailments because of H. pylori.  相似文献   
56.
MicroRNAs (miRNAs) are endogenous mediators of RNA interference and have key roles in the modulation of gene expression under healthy, inflamed, stimulated, carcinogenic, or other cells, and tissues of a pathological state. Many studies have proved the association between miRNAs and cancer. The role of miR-326 as a tumor suppressor miRNA in much human cancer confirmed. We will explain the history and the role of miRNAs changes, especially miR-326 in cancers and other pathological conditions. Attuned with these facts, this review highlights recent preclinical and clinical research performed on miRNAs as novel promising diagnostic biomarkers of patients at early stages, prediction of prognosis, and monitoring of the patients in response to treatment. All related publications retrieved from the PubMed database, with keywords such as epigenetic, miRNA, microRNA, miR-326, cancer, diagnostic biomarker, and therapeutic target similar terms from 1899 to 2018 with limitations in the English language. Recently, researchers have focused on the impacts of miRNAs and their association in inflammatory, autoinflammatory, and cancerous conditions. Recent studies have suggested a major pathogenic role in cancers and autoinflammatory diseases. Investigations have explained the role of miRNAs in cancers, autoimmunity, and autoinflammatory diseases, and so on. The miRNA-326 expression has an important role in cancer conditions and other diseases.  相似文献   
57.
Hepatocellular carcinoma (HCC) is one of the lethal and difficult-to-cure cancers worldwide. Owing to the late diagnosis and drug resistance of malignant hepatocytes, treatment of this cancer by conventional chemotherapy agents is challenging, and researchers are seeking new alternative treatment options to overcome therapy resistance in this neoplasm. RNA interference (RNAi) is a potent and specific approach in targeting gene expression and has emerged as a novel therapeutic tool for many diseases, including cancers. Small interfering RNA (siRNA) is a type of RNAi that is produced intracellularly from exogenous synthetic oligonucleotides and can selectively knock down target gene expression in a sequence-specific manner. Various factors play roles in the initiation and progression of HCC and provide multiple candidate targets for siRNA intervention. In addition, due to the liver's unique architecture and availability of some hepatic siRNA delivery methods, this organ has received much more attention as a target tissue for such oligonucleotide action. Recent advances in designing nanoparticle systems for the in vivo delivery of siRNAs have markedly enhanced the potency of siRNA-mediated gene silencing under clinical development for HCC therapy. The utility of siRNAs as anti-HCC agents is the subject of the current review. siRNA-based gene therapies could be one of the main feasible approaches for HCC therapy in the future.  相似文献   
58.
Background and Objectives: Saussurea lappa (S. lappa) is an important species of the Asteraceae family with several purposes in traditional medicine. This study intended to explore the cytotoxic effect of S. lappa on HepG2 cancer cell proliferation. Materials and Methods: The effects of an S. lappa n-butanol extract on the induction of apoptosis were investigated by flow cytometry and mitochondrial cytochrome C-releasing apoptosis assay. Additionally, real-time PCR was employed to confirm apoptosis initiation. Further, qualitative estimation of the active constituent of S. lappa was done by gas chromatography–mass spectroscopy (GC–MS). Results: The cell viability study revealed that the n-butanol extract of S. lappa demonstrated potent cytotoxicity against HepG2 cancer cells, with an IC50 value of 56.76 μg/mL. Cell morphology with dual staining of acridine orange (AO)-ethidium bromide (EB) showed an increase in orange/red nuclei due to cell death by S. lappa n-butanol extract compared to control cells. Apoptosis, as the mode of cell death, was also confirmed by the higher release of cytochrome C from mitochondria, the increased expression of caspase-3 and bax, along with down regulation of Bcl-2. Conclusion: These findings conclude that S. lappa is a cause of hepatic cancer cell death through apoptosis and a potential natural source suggesting furthermore investigation of its active compounds that are responsible for these observed activities.  相似文献   
59.
Direct association of RhoA with specific domains of PKC-alpha   总被引:1,自引:0,他引:1  
Previous studies performed at our laboratory have shown that agonist-induced contraction of smooth muscle is associated with translocation of protein kinase C (PKC)- and RhoA to the membrane and that this interaction is due to a direct protein-protein interaction. To determine the domains of PKC- involved in direct interaction with RhoA, His-tagged PKC- proteins of individual domains and different combinations of PKC- domains were used to perform in vitro binding assays with the fusion protein glutathione-S-transferase (GST)-RhoA. Coimmunoprecipitation was also performed using smooth muscle cells transfected with truncated forms of PKC- in this study. The data indicate that RhoA directly bound to full-length PKC-, both in vitro (82.57 ± 15.26% above control) and in transfected cells. RhoA bound in vitro to the C1 domain of PKC- [PKC- (C1)] (70.48 ± 20.78% above control), PKC- (C2) (72.26 ± 29.96% above control), and PKC- (C4) (90.58 ± 26.79% above control), but not to PKC- (C3) (0.64 ± 5.18% above control). RhoA bound in vitro and in transfected cells to truncated forms of PKC-, PKC- (C2, C3, and C4), and PKC- (C3 and C4) (94.09 ± 12.13% and 85.10 ± 16.16% above control, respectively), but not to PKC- (C1, C2, and C3) or to PKC- (C2 and C3) (0.47 ± 1.26% and 7.45 ± 10.76% above control, respectively). RhoA bound to PKC- (C1 and C2) (60.78 ± 13.78% above control) only in vitro, but not in transfected cells, and PKC- (C2, C3, and C4) and PKC- (C3 and C4) bound well to RhoA. These data suggest that RhoA bound to fragments that may mimic the active form of PKC-. The studies using cells transfected with truncated forms of PKC- indicate that PKC- (C1 and C2), PKC- (C1, C2, and C3), and PKC- (C2 and C3) did not associate with RhoA. Only full-length PKC-, PKC- (C2, C3, and C4), and PKC- (C3 and C4) associated with RhoA. The association increased upon stimulation with acetylcholine. These results suggest that the functional association of PKC- with RhoA may require the C4 domain. domains; histidine; fusion proteins  相似文献   
60.
The aim of this study was to investigate the effect of HDL oxidation on PON1 paraoxonase activity. Also, we were interested in investigating the mechanism by which PON1 could be inactivated and the correlation between its enzymatic activity and the antioxidant properties of HDL. Three different oxidation systems were used for the HDL oxidation: (1) oxidation induced by THP1 cells, (2) oxidation induced by copper ions at a concentration 10 &#119 M, and (3) oxidation induced by &#148 OH and O 2 &#148 &#109 oxygen free radicals produced by &#110 -radiolysis. HDL oxidation was followed by the measurement of lipid peroxide formation, and PON1 activity was determined by measuring the rate of paraoxon hydrolysis. Our results show that HDL oxidation is accompanied by a reduction in the PON1 paraoxonase activity. The extent of PON1 inactivation depends both on the extent of HDL oxidation and on the oxidation system used. The rates of HDL oxidation and PON1 inactivation were significantly correlated ( r =0.93, p <0.0054). Our results show that oxidized HDL loses its protective effect toward LDL oxidation. The antioxidant action of HDL towards LDL oxidation and the degradation of PON1 paraoxonase activity were significantly correlated ( r =0.95, p <0.04).  相似文献   
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