ABSTRACT
Curcumin, the active ingredient of turmeric, has the ability to inhibit the carcinogenic pathways, and thus can prevent or postpone the carcinogenic process in different animal species. Retention time of curcumin is short due to the quick excretion of the body, so, the therapeutic effects of curcumin are restricted resulting in short-term retention in the plasma. Therefore, several methods are used for increasing the efficiency of curcumin in plasma and tissues. The present study is designed to evaluate the effects of the anti-proliferative and anti-carcinogenic of nano-curcumin in rat colon cancer. In this study which was performed in Cancer Research Center of Tehran University of Medical Sciences in 2012. Thirty rats have divided into control, curcumin and nano-curcumin groups. All animals received azoxymethane [15 mg/kg, s.c] as a carcinogen, once a week for two consecutive weeks. Animals received curcumin 0.2% and nano-curcumin 2 weeks before azoxymethane injection up to 14 weeks after the last injection of azoxymethane in curcumin and nano-curcumin groups, respectively. At the end of experiment, the colorectal specimens from all mucosal lesions were obtained for histo-and-immunohistochemical [Ki-67 and COX-2] studies. The cytological and morphological changes of the cells in nano-curcumin group were significantly lower compared to other groups [P<0.05]. In addition, the Ki- 67 and COX-2 proteins expression was lower in the nano-curcumin group in compareson with the curcumin and control groups [P<0.05]. The results indicate that the using a suitable nanoparticle can be appropriately resolved the low bioavailability of curcumin. This can be an important method to use of natural products in the prevention and/or treatment of cancer.
Subject(s)
Animals, Laboratory , Cell Proliferation/drug effects , Antineoplastic Agents , Nanoparticles , Colonic Neoplasms , Rats , Ki-67 Antigen , Cyclooxygenase 2ABSTRACT
The 3-hydroxy-3-methylglutaryl-coenzyme A [HMG-CoA] reductase inhibitors [statins] have revolutionized the treatment of hypercholesterolemia. Some evidence indicated the role of nodal refractoriness and concealed conduction in anticipating the ventricular rate during atrial fibrillation. Recent evidence has indicated that statins can reduce the incidence of both supraventricular and ventricular arrhythmias. The aim of the present study is to investigate adenosine A1 receptor role on simvastatin protective effects on atrioventricular nodal properties in isolated atrial fibrillation model of rabbit heart. The present study was performed in cardiovascular research center of Golestan University of Medical Sciences in 2012. Recovery and atrial fibrillation protocols were used to study electrophysiological properties of atrioventricular node in 5 groups of male Newsland rabbits [n=40]. Extracellular recording was carried out from transitional cells of posterior and anterior extension of AV-node and upper part of atrium and its bundle. All stimuli protocols repeated in the presence of adenosine A1 receptor agonist and antagonist [dipridamole and CPX] alone or with simvastatin on isolated perfused atrio-nodal preparation. Extracellular field potential recording was sampled during specific stimulation protocols. Significant inhibition was observed in basic node properties such as wenckebach prolongation, functional refractory period, effective refractory period and atrioventricular node conduction time with simvastatin [P<0.05]. Simvastatin prolonged His-His interval and increased number of concealed beat in atrial fibrillation protocol [P<0.05]. The simvastatin protective effects on atrioventricular nodal properties were intensified by dipridamole as an adenosine A1 receptor agonist [P<0.05], but CPX as an adenosine A1 receptor antagonist could only dampen them [P>0.05]. Our results showed that the use of adenosine agonist increased simvastatin effects on electrophysiological properties of atrioventricular node, but its antagonist could not prevent these effects. This may indicate simvastatin protective mechanism on atrioventricular node electrophysiological properties without adenosine direct involvement
ABSTRACT
Fumonisins, a family of mycotoxins, are mainly found in wheat, corn and their products. Previous studies have shown that fumonisin B1 [FB1], the most abundant and toxic of known fumonisins, has been associated with many animal and human diseases including cancer. In the present study, the effects of FB1 were examined on the production of inflammatory cytokines in intestine and stomach cell lines. This study was performed in the Cancer Research Center of Tehran University of Medical Sciences in 2010. The cell lines of colon adenocarcinoma [SW742] and gastric epithelium [AGS] were purchased from the Pasteur Institute of Iran. The cells were pretreated with different concentrations of FB1 [0 to 100 micro M] for 3 days. The cells were later stimulated by lipopolysaccharides. Twenty-four hours after cell induction, the cytokines including tumor necrosis factor-alpha [TNF- alpha], interlukin-1 beta [IL-1 beta] and interlukin-8 [IL-8] were measured by ELISA. Treatment with FB1 induced a dose-dependent decrease in IL-8 production [P<0.05]. This decrease was seen in both SW742 and AGS cell lines. Moreover, FB1 induced a dose-dependent increase in the production of TNF- alpha and IL-1 beta in both cell lines [P<0.05]. The results of this study indicated that FB1 could increase the inflammatory cytokines including TNF- alpha and IL-1 beta in gastric and intestinal cell lines. These effects might result in the development of inflammatory responses and subsequent mucosal atrophy in in-vivo conditions
ABSTRACT
Cancer is a multistep process that develops very rapidly after its onset. Previous studies have confirmed antitumor effects of curcumin [1,7-bis [4-hydroxy-3-methoxyphenyl]-l,6-heptadiene-3,5-dione; diferuloylmethane] that can potentially prevent colon cancer development with low side-effects. Different methods have been performed to increase the efficiency and effectiveness of curcumin among which dendrosome, a nanoparticle created by Sarbolouki et al. was used in this study. The present study was undertaken to evaluate the effects of dendrosomal curcumin on rat colon cancer. In this study which was performed in Cancer Research Center of Tehran University of Medical Sciences in 2010 year, forty rats were equally divided into control, curcumin and curcumin-dendrosome groups. Animals received azoxymethane [15 mg/kg s.c.], a carcinogen, once a week for two weeks. Curcumin [0.2%] and curcumin-dendrosome were administered to the respective animals 2 weeks before the first and 14 weeks after the last azoxymethane injections. Eventually, colorectal specimens from tumoral and adjacent non-tumoral mucosal tissues were fixed in 10% formaldehyde, and passaged and embedded in paraffin. Histopathological and immunohistochemical studies were performed on the specimens. The mean number of lesions, nuclear/cytoplasmic ratio, epithelial stratification, loss of nuclear polarity, goblet depletion, structural abnormality and beta-catenin expression were higher in the control group compared to curcumin and curcumin-dendrosome groups. These parameters had significantly decreased in the dendrosomal curcumin group [P<0.05]. The present study shows that dendrosome can be used as a suitable nanoparticle to increase curcumin efficiency in the prevention or treatment of colon cancer