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Several mechanisms have been proposed to explain berries' anticancer effects. However, no previously published studies have investigated berries' anti-telomerase activity. In this study, the anti-telomerase activity of blackberry crude extract was analyzed in six human colorectal cancer (CRC) cell lines by TRAP assay. The peripheral blood mononuclear cells (PBMCs) from a healthy donor were used as a normal control. We also examined the effect of blackberry on the human telomerase RNA (hTR) mRNA level and on human telomerase reverse transcriptase (hTERT) expression and promoter methylation in CRC cells. Blackberry extract significantly inhibited the growth of six CRC cell lines in a dose-dependent manner. Telomerase activity of CRC cells incubated with the IC50 concentration of berry's extract for 48 and 72 h decreased by 15%-37.5% and 43.23%-62.5% (P < 0.05), respectively. In cell-free assays, treatment with as little as 7 µl/ml of berry juice completely blocked telomerase activity in CRC cell lysates. Berry was much less effective in inhibiting telomerase activity in normal PBMCs than CRC cells. Berry treatment reduced hTERT expression and its promoter methylation in CRC cell lines, but the expression of hTR was less influenced by the treatment. Our data indicate that telomerase inhibition is a key mechanism by which blackberry exerts its anticancer effects in CRC cells.
Assuntos
Neoplasias Colorretais/enzimologia , Extratos Vegetais/farmacologia , Rubus/química , Telomerase/antagonistas & inibidores , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Frutas/química , Expressão Gênica/efeitos dos fármacos , Humanos , Extratos Vegetais/análise , Regiões Promotoras Genéticas/genética , RNA/genética , RNA Mensageiro/análise , Telomerase/genéticaRESUMO
Acute unilateral ureteral obstruction (UUO) impairs distal nephron acid secretion and stimulates expression of inducible nitric oxide synthase (iNOS) in post-obstructed kidney (POK). This study investigated the influence of pre- or post-treatment with aminoguanidine as a selective iNOS inhibitor on UUO-induced renal functional disturbances. To induce acute UUO, the left ureter in rats was ligated and released after 24 h. Then, a 3 h clearance period followed by bicarbonate loading and thereafter a 30 min clearance period were allocated. Aminoguanidine was administered either prior to the UUO induction or after release of the obstruction in the different rat groups, while untreated and sham groups received normal saline. During the first clearance period, fractional bicarbonate excretion and urinary pH increased markedly in the POK of the untreated group compared with the left kidney of sham group, and a large drop in the difference between urine and blood pCO2 (U-B pCO2) was observed after bicarbonate loading; all of these parameters were ameliorated in the pre-treated and post-treated groups. However, the UUO-induced decreases in creatinine clearance, sodium reabsorption, urine osmolality, and free-water reabsorption in the POK were attenuated only in the post-treated group. Therefore, the in vivo application of a selective iNOS inhibitor partially improved the acute UUO-induced distal nephron acidification defect, while post-treatment but not pre-treatment with aminoguanidine ameliorated decrements of glomerular filtration, sodium reabsorption, and urine-concentrating ability.
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Inibidores Enzimáticos/farmacologia , Guanidinas/farmacologia , Túbulos Renais Distais/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/metabolismo , Animais , Pressão Arterial/efeitos dos fármacos , Bicarbonatos/farmacologia , Gasometria , Taxa de Filtração Glomerular , Concentração de Íons de Hidrogênio , Testes de Função Renal , Masculino , Concentração Osmolar , Potássio/sangue , Ratos , Ratos Sprague-Dawley , Sódio/sangue , Sódio/urinaRESUMO
BACKGROUND: Hereditary hemochromatosis (HH) is the most common autosomal recessive disorder in white people, characterized by highly abnormal uptake of iron from the gastrointestinal tracts. Recently, mutation studies have focused to detect the genes responsible for HH. MATERIAL/METHODS: In this cross-sectional study, 12 HH patients were recruited, who were referred to Firoozgar Hospital, Tehran, Iran. In addition to the clinical assessments, a complete laboratory evaluation, imaging modalities, histopathologic assessment, atomic absorption spectrophotometry and gene mutation study were performed. The genetic study for HFE gene mutation was examined for all of the patients since 2006, while non-HFE mutation was conducted since December 2010 (only for 1 of them). RESULTS: Twelve patients were evaluated consisting of 11 men and 1 woman, with the mean age of 39.58±12.68 yr. The average of atomic iron loads was 13.25±4.83-fold higher than normal standards. Four patients had heterozygotic mutation of H63D (33.3%). There was no significant difference in either the iron load of liver (P=0.927) and heart (P=0.164) or serum concentration of ferritin (P=0.907) and TIBC (P=0.937) between the HFE-mutant and without HFE mutation HH cases. CONCLUSIONS: In contrast to other studies, C282Y mutation was not detected in any of our Iranian HH patients. Heterozygotic mutations of H63D (HFE) and TFR2 (non-HFE) genes were found to be more common in these patients. Similar to previous reports, these mutations were not found to be significantly associated with severity of presentation in HH patients.
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Técnicas de Laboratório Clínico , Hemocromatose/sangue , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Padrões de Herança/genética , Proteínas de Membrana/genética , Mutação/genética , Adulto , Feminino , Hemocromatose/diagnóstico por imagem , Hemocromatose/patologia , Proteína da Hemocromatose , Humanos , Irã (Geográfico) , Imageamento por Ressonância Magnética , Masculino , UltrassonografiaRESUMO
Cancer as a second leading cause of death arises from multifactorial pathology. The association of microbiota and their products with various pathologic conditions including cancer is receiving significant attention over the past few years. Mounting evidence showed that human microbiota is an emerging target in tumor onset, progression, prevention, and even diagnosis. Accordingly, modulating this composition might influence the response to tumor therapy and therapeutic resistance as well. Through this review, one could conceive of complex interaction between the microbiome and cancer in either positive or negative manner by which may hold potential for finding novel preventive and therapeutic strategies against cancer.
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The role of exosomes and their mechanism of action at the tumor site have received increasing attention. These microvesicles are produced by a wide range of cells including mesenchymal stem cells (MSCs) and immune cells. In particular, tumor cells release remarkable amounts of exosomes which spread to distant organs through the blood and enhance the possibility of tumor metastasis. In spite of results on tumor promoting properties, there are reports demonstrating the tumor inhibiting effects of exosomes depending on the type of the tumor and cell source. This review aims to have a comprehensive appraisal on the biogenesis, composition, and isolation of exosomes and then highlights the current knowledge of their role in cancer progression or inhibition by special focusing on MSC's exosomes (MSC-EXOs).
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Introduction: The present study addressed whether methylprednisolone (MP) as an anti-inflammatory drug used in neurodegenerative diseases and neural stem/progenitor cells (NS/PCs) is safe. Methods: First, embryonic rat NS/PCs were exposed to different concentrations of MP, and then we evaluated their survival by MTT assay, proliferation by analyzing the number and diameter of neurospheres, and the migration of the cells by neurosphere assay. Results: The viability of NS/PCs was reduced following exposure to 10, 15, and 20 µg/mL of MP. In addition, although the number of neurospheres did not change, exposure to different concentrations of MP resulted in the formation of smaller neurospheres. Despite these undesirable effects, the highest concentration of MP (20 µg/mL) increased the migration capacity of the NS/PCs. Conclusion: The combination of MP and NS/PCs is not recommended due to the adverse effects of MP on the survival and proliferation of NS/PCs. Highlights: Methylprednisolone reduced survival of neural stem/progenitor cells.Methylprednisolone decreased proliferation of neural stem/progenitor cells.The highest concentration of MP (20 µg/mL) increased the migration capacity of the neural stem/progenitor cells. Plain Language Summary: In this study, we evaluate the effect of the exposure of neural stem/progenitor cells to methylprednisolone. Based on the results, combination of neural stem/progenitor cells and methylprednisolone not recommended due to reduction of survival and proliferation of the cells.
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Zidovudine (ZDV) is an antiviral drug against HIV that was approved by the FDA on March, 1987. It is a reverse transcriptase inhibitor. This type of drug stops the reproduction of DNA and decreases the amount of the virus in the patients' blood. Due to the ability of forming various molecular bonds, silver nanoparticles (AgNPs) are widely used for the detection of large range of agents, including drugs. In this study, we synthesized AgNP-modified ß-cyclodextrin (ß-CD) using green synthesis for the sensitive and selective zidovudine (ZDV) determination. Characterization of nanoparticles was done using different methods including infrared (IR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, transmission electron microscopy (TEM), and also, X-ray diffraction (XRD) patterns. The AgNP λ-max peak was at approximately 405 nm. In the presence of ZDV, yellow solution was turned to red color, and surface plasmon absorption band was dramatically centered at 560 nm. ZDV was determined in the range of 50-500 µM, and the detection limit value was obtained as 42 µM. The sensor was used to determine ZDV in tablets with good recovery.
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OBJECTIVES: Severe injuries are often associated with tissue hypothyroidism, elevated damaging mediators in circulation, and broken gut epithelial barrier. However, the relationships between the hypothyroid state and gut epithelial damage are largely unknown. Therefore, in this study, we investigated the effects of L-thyroxine (T4) on in vitro models of intact and compromised gut epithelium. MATERIALS AND METHODS: Gut epithelium equivalent was generated by cultivation of IEC-18 rat intestinal epithelial cells into transwell inserts. Confluent cultures were then compromised by scratching or H2O2 and traumatized rat sera (TUR sera) treatments. Macromolecules permeation and transepithelial electrical resistance (TEER) were evaluated by conventional methods. Morphology and scratch wound closure were assessed microscopically. Cell viability/proliferation was assessed by MTT assay. RESULTS: Both H2O2 and TUR sera induced marked yet different types of epithelial disintegration. While H2O2 significantly increased and decreased probe permeation and TEER, respectively, TUR sera was ineffective. Cultures treated with normal rat sera (sham sera) exhibited morphology, probe permeation, and TEER comparable to those of control cultures. Presence of T4 attenuated the H2O2-induced but not TUR sera-induced damages. T4 treatment accelerated, albeit marginally, wound closure but had virtually no effects on cell viability/proliferation. CONCLUSION: These data suggest that different mechanisms are involved in oxidant- and trauma-induced gut epithelial barrier breakdown. Besides, they show that T4 markedly attenuates oxidant-induced gut epithelial damage. Accordingly, one may also conclude that tissue hypothyroidism does not contribute to trauma-induced gut barrier breakdown.
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INTRODUCTION: Vitamin D has been suggested to play a considerable role in the function of the immune system in various infectious, inflammatory, and autoimmune conditions. Otitis media with effusion (OME), defined as the presence of non-purulent fluid within the middle ear without signs or symptoms of suppurative otitis media, has a number of inflammatory predisposing factors. This study was designed to explore the association between vitamin D deficiency and OME. MATERIALS AND METHODS: In this cross-sectional study, 74 children aged 2-7 years with an obstructive indication for adenotonsillectomy were included. Patients were divided into two groups based on the need for ventilation tube insertion for OME. Thirty-two children were enrolled in the OME group and 42 in the control group. The mean vitamin D level was compared between the two groups. RESULTS: Mean vitamin D concentration in all patients was 11.96±5.85 ng/ml (9.79±4.36 ng/ml in the OME group and 13.61±6.33 ng/ml in the control group; P=0.003). There was also a significant difference in levels of vitamin D in patients referred in winter (9.0±2.94 ng/ml) compared with the summer (19.85±4.21 ng/ml; P=0.001). Data analyzed based on the season in which the patients were referred showed no significant difference between the OME and the control group. CONCLUSION: Although our results showed lower serum levels of vitamin D in OME patients, the difference was not significant when seasons were taken into consideration. Therefore, the season is an important confounding factor in any research related to vitamin D due to the effect of sun-induced vitamin D.