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71.
Phloridzin reduces blood glucose levels and improves lipids metabolism in streptozotocin-induced diabetic rats 总被引:2,自引:0,他引:2
Najafian M Jahromi MZ Nowroznejhad MJ Khajeaian P Kargar MM Sadeghi M Arasteh A 《Molecular biology reports》2012,39(5):5299-5306
Phloridzin is the specific and competitive inhibition of sodium/glucose cotransporters in the intestine (SGLT1) and kidney
(SGLT2). This property which could be useful in the management of postprandial hyperglycemia in diabetes and related disorders.
Phloridzin is one of the dihydrochalcones typically contained in apples and in apple-derived products. The effect of phloridzin
orally doses 5, 10, 20 and 40 mg/kg body weight on diabetes was tested in a streptozotocin-induced rat model of diabetes type
1. From beneficial effect of this compound is significant reduction of blood glucose levels and improve dyslipidemia in diabetic
rats. As a well-known consequence of becoming diabetic, urine volume and water intake were significantly increased. Administration
of phloridzin reduced urine volume and water intake in a dose-dependent manner. Phloretin decreases of food consumption, as
well as a marked lowering in the weight. In conclusion, this compound could be proposed as an antihyperglycemic and antihyperlipidemic
agent in diabetes and potential therapeutic in obesity. 相似文献
72.
Forty samples of dried vine fruit (raisin, n?=?22; currant, n?=?18) were collected in 2009?C2011 from the Iranian market. Aflatoxins (AFs) and ochratoxin A (OTA) were determined in these samples after immunoaffinity column clean-up by high performance liquid chromatography (HPLC) with fluorescence detection. The limit of quantification (LOQ) for AFs B1. B2, G1, G2, and OTA were 0.62, 0.50, 0.70, 0.40, and 0.42?ng/g, respectively. AFB1 was found in one sample of raisin (0.64?ng/g) and in two samples of currant (0.20 and 0.63?ng/g). AFB2 (0.33?ng/g) and AFG2 (0.49?ng/g) were found in 2 samples of currant. OTA was detected in 3 of the 22 samples of raisin (mean 2.21?ng/g) and in one sample of currant (2.99?ng/g). The results show that in AFs and OTA levels are well below the regulatory limits both of the European Union and of Iran. 相似文献
73.
A free-ranging, adult, male Persian leopard (Panthera pardus ciscaucasica) was found at Geloul-Sarani protected zone, province of North-Khorasan, Iran and transported to the Ferdowsi University of Mashhad Veterinary Teaching Hospital. The leopard had normal temperature and respiratory and cardiac frequency, but was significantly dehydrated and had elevated capillary perfusion. The animal also was cachectic, with pale mucus membranes, third-eyelid protrusion, and bilaterally enlarged submandibular lymph nodes. The leopard was stabilized by intensive fluid and electrolyte therapy and hospitalized. In 2 days, the leopard had improved clinically but had severe ataxia and head pressing. Blood smears revealed gamonts of Hepatozoon sp. within some neutrophils. Hematologic and plasma chemistry abnormalities included moderate anemia, leukocytosis, hypocholestrolemia, and hypophosphatemia. In radiographic evaluations, no sign of periosteal reactions or new bone formation was seen on the skull, spine, long bones, pelvis, or vertebrae. The leopard was treated successfully with Tazocin and clindamycin for 1 mo. This is the first detection of a Hepatozoon sp. in wild Felidae in Iran. Because most Iranian wild felids and canids are endangered, knowing whether Hepatozoon infection represents a threat for these animals is important. 相似文献
74.
R Ghorbani-Nasrabadi R Greiner HA Alikhani J Hamedi 《World journal of microbiology & biotechnology》2012,28(7):2601-2608
In this study 97 soil samples from different soil ecosystems were collected. The initial screening was performed on modified glycerol arginine agar (MGAA) to isolate common actinomycetes and on modified MGA-SE (MMGA-SE) to isolate rare actinomycetes. Sixty-seven isolates potentially producing extracellular phytate-degrading activity were identified. The potential to dephosphorylate phytate was confirmed in liquid culture for 46.3 % of the isolates. 12 strains were selected for a direct determination of their phytate-degrading capacity. The results highlighted that the selected isolates produced extracellular phytate-degrading activity; however their capacity in InsP(6) degradation was different. In addition the fermentation medium had an effect on the extent of phytate degradation. Some enzymatic properties of the phytases from isolate No. 43 and isolate No. 63 were determined after obtaining phytase-enriched samples. The enzymes had maximum phytate-degrading capability at 55 °C and pH 5 (isolate No. 43) and 37 °C and pH 7 (isolates No. 63), respectively. Due to their properties, the phytase of isolate No. 43 behaves like a histidine acid phytase, whereas the phytase of No. 63 showed similar enzymatic properties to the phytase of lily. To our knowledge, the results from this study demonstrated for the first time that actinomycetes produce extracellular phytate-degrading activity. By 16SrRNA sequencing, the more closely studied phytase producers were identified as Streptomyces sp. Isolate No. 43 showed 98 % identity to Streptomyces alboniger and S. venezuelae, while isolate No. 63 exhibited 98 % sequence identity to S. ambofaciens and S. lienomycini. 相似文献
75.
M Noureddini J Verdi SA Mortazavi-Tabatabaei S Sharif A Azimi P Keyhanvar A Shoae-Hassani 《Cell biology international》2012,36(10):961-966
The potential of cell therapy is promising in nerve regeneration, but is limited by ethical considerations about the proper and technically safe source of stem cells. We report the successful differentiation of human EnSCs (endometrial stem cells) as a rich source of renewable and safe progenitors into high-efficiency cholinergic neurons. The extracellular signals of NGF (nerve growth factor) and bFGF (basic fibroblast growth factor) could induce cholinergic neuron differentiation. ChAT (choline acetyltransferase), MAP2 (microtubule associated protein 2) and NF-l (neurofilament L) increased after administration of bFGF and NGF to the EnSC cultures. trkC and FGFR2 (fibroblast growth factor receptor 2), which belong to the NGF and bFGF receptors respectively, were determined in populations of EnSCs. NGF, bFGF and their combination differentially influenced human EnSCs high efficiency differentiation. By inducing cholinergic neurons from EnSCs in a chemically defined medium, we could produce human neural cells without resorting to primary culture of neurons. This in vitro method provides an unlimited source of human neural cells and facilitates clinical applications of EnSCs for neurological diseases. 相似文献
76.
Lithium preparations are commonly used drug in treating mental disorders and bipolar diseases, but metal's cytotoxic mechanisms have not yet been completely understood. In this study, we investigated the cytotoxic mechanisms of lithium in freshly isolated rat hepatocytes. Lithium cytotoxicity were associated with reactive oxygen species (ROS) formation and collapse of mitochondrial membrane potential and cytochrome c release into the hepatocyte cytosol. All of the mentioned lithium-induced cytotoxicity markers were significantly (P?0.05) prevented by ROS scavengers, antioxidants, mitochondrial permeability transition pore sealing agents and adenosine triphosphate generators. Hepatocyte glutathione (GSH) was also rapidly oxidized and GSH-depleted hepatocytes were more resistant to lithium-induced oxidative stress markers. This suggests that lithium is activated by GSH. Our results also showed that CYP2E1 is involved in lithium oxidative stress mechanism. Lithium cytotoxicity was also associated with mitochondrial injuries initiated by increased ROS formation resulted from metal-CYP2E1 destructive interaction or metal-induced disruption of mitochondrial electron transfer chain. Methyl donors such as betaine, methionine, or folic acid prevented lithium cytotoxicity, and this suggests that this metal is detoxified by phase II metabolic methylation. In conclusion lithium-induced cytotoxicity could be attributed to oxidative stress and mitochondrial dysfunction. 相似文献
77.
Lastra G Whaley-Connell A Manrique C Habibi J Gutweiler AA Appesh L Hayden MR Wei Y Ferrario C Sowers JR 《American journal of physiology. Endocrinology and metabolism》2008,295(1):E110-E116
Renin-angiotensin-aldosterone system (RAAS) activation mediates increases in reactive oxygen species (ROS) and impaired insulin signaling. The transgenic Ren2 rat manifests increased tissue renin-angiotensin system activity, elevated serum aldosterone, hypertension, and insulin resistance. To explore the role of aldosterone in the pathogenesis of insulin resistance, we investigated the impact of in vivo treatment with a mineralocorticoid receptor (MR) antagonist on insulin sensitivity in Ren2 and aged-matched Sprague-Dawley (SD) control rats. Both groups (age 6-8 wk) were implanted with subcutaneous time-release pellets containing spironolactone (0.24 mg/day) or placebo over 21 days. Systolic blood pressure (SBP) and intraperitoneal glucose tolerance test were determined. Soleus muscle insulin receptor substrate-1 (IRS-1), tyrosine phosphorylated IRS-1, protein kinase B (Akt) phosphorylation, GLUT4 levels, and insulin-stimulated 2-deoxyglucose uptake were evaluated in relation to NADPH subunit expression/oxidase activity and ROS production (chemiluminescence and 4-hydroxy-2-nonenal immunostaining). Along with increased soleus muscle NADPH oxidase activity and ROS, there was systemic insulin resistance and reduced muscle IRS-1 tyrosine phosphorylation, Akt phosphorylation/activation, and GLUT4 expression in the Ren2 group (each P < 0.05). Despite not decreasing blood pressure, low-dose spironolactone treatment improved soleus muscle insulin signaling parameters and systemic insulin sensitivity in concert with reductions in NADPH oxidase subunit expression/activity and ROS production (each P < 0.05). Our findings suggest that aldosterone contributes to insulin resistance in the transgenic Ren2, in part, by increasing NADPH oxidase activity in skeletal muscle tissue. 相似文献
78.
BACKGROUND: Angiolymphoid hyperplasia with eosinophilia (ALHE) is an uncommon vascular inflammatory lesion usually involving the dermis or subcutaneous tissue of the head-neck region of middle-aged women. Histologically, this lesion shows a florid proliferation of vessels lined by particular endothelial cells and an inflammatory infiltrate composed of lymphocytes and eosinophils. CASE: A 30-year-old woman presented with multiple periauricular skin nodules. Fine needle aspiration cytology shows a mixed population of lymphoid cells with an admixture of eosinophils and large cells with vesicular nuclei and prominent nucleoli. A diagnosis of AHLE was confirmed on histopathologic examination. CONCLUSION: Various conditions, both benign and malignant, may mimic Kimura's disease clinically and on smears. These must be ruled out before making a diagnosis of Kimura's disease. The cytologic features of Kimura's disease have to be interpreted in the appropriate clinical setting in order to make a correct preoperative diagnosis. 相似文献
79.
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