158 research outputs found
IN-VITRO CYTOTOXIC EFFECT OF CANTHIUM DICOCCUM ON DIFFERENT CANCER CELL LINES
Objective: Cancer remains one of the most dreaded diseases causing an astonishingly high death rate. Despite the use of surgical resection and aggressive chemotherapy, nearly 50% of patients with carcinoma develop recurrent disease, highlighting the need for improved therapies. Henceforth, complementary and alternative medicine is slowly emerging as an option. A variety of ingredients of traditional medicines and herbs are being widely investigated in several parts of the world to analyze their potential as therapeutic agents against cancer. In the present study we investigated the efficacy of methanol extracts of Canthium dicoccum, for its clonogenic inhibition on Human Breast cancer (MD-MB-231), Prostate cancer (PC-3) and Lung cancer (Calu-6) cell lines.Methods: The cytotoxic effect of methanolic extract of Canthium dicoccum was evaluated by MTT assay on MD-MB-231, Calu-6, and PC-3 cells.Results: The methanol extract of C. dicoccum showed significant cytotoxicity against MD-MB-231and Calu-6, when compared to PC-3 cells.Conclusion: The methanol extracts of C. dicoccum showed effective cytotoxic activities in a dose and time dependent manner. Future work will be interesting to know the chemical composition and also better understanding the mechanism of action will help in developing it as drug for therapeutic application.Â
SCREENING FOR BIOACTIVES FROM INDIAN MEDICINAL HERBS – A SIMPLISTIC APPROACH FOR ANTIOXIDANT METABOLITES
Herbal extracts obtained from 20 Indian medicinal plants were evaluated for their cytoprotectivity on erythrocytes and antioxidant properties. Total phenol content and anti-rhizopus activity were also determined. Results indicated that, out of 20 extracts evaluated, radical scavenging capacity and anti-rhizopus activity were observed in aqueous extract of Ocimum tenuiflorum, Leucas aspera, Terminalia arjuna, Glycyrrhiza glabra and Nyctanthes arbortristis in a dose dependent manner. The total phenolic content was observed to be 1289, 3837, 372, 2831 and 1892 μg GAE/g for O. tenuiflorum, L. aspera, T. arjuna, G. glabra and N. arbortristis respectively. The antioxidant activity correlates with the phenolic content of the extracts. At 1 mg/ml the above extracts showed 98% protection on erythrocyte cell oxidation. These results demonstrate that the cytoprotectivity and antioxidant potency of these extracts could be the basis for their alleged health promoting potential. These herbs could serve as new sources of natural antioxidants or nutraceuticals with potential applications in reducing oxidative stress conditions.Â
PHYTO-ANTIQUORUMONES: AN HERBAL APPROACH FOR BLOCKING BACTERIAL TRAFFICKING AND PATHOGENESIS
Over centuries, plants are the richest resource of curative drugs as cited in folklore, traditional and modern medicinal systems and are been used as nutraceuticals, functional food supplements and in pharmaceuticals. Phytochemicals have exhibited beneficial effects against human acute and chronic ailments caused due to microbial pathogens. In recent years, phytochemicals and their derivatives have been extensively used as potent antimicrobials in humans and livestock due to their chemical stability, high bioavailability, low-molecular mass, safe consumption without any side-effect as seen in many antibiotic regimes. These phytocompounds have also been highlighted to function as Quorum Sensing Inhibitors (QSI) or antiquorumones in blocking bacterial pathogenesis preventing their regulatory mechanism and expression of specific set of virulence genes or cascades. However, the role of phytochemicals as QSI has been poorly identified but many of which remain unexplored. Therefore, this review summarizes most of the current scientific contributions focused on the use of plant phytochemicals as antiquorumones, highlighting the significance of plant derived molecules as bacterial inhibitors with larger emphasis on the mechanistic action of biofilm formation and quorum signaling networks mainly N-acylhomoserine lactones (AHLs), autoinducer-2 (AI-2) communications and their attributes in modulating the host immune response. A critical understanding of this complex trio-interaction between humans, microbes and phytochemicals has to be well explored, to exploit the usefulness of these metabolites ultimately paving newer paths for herbal drug discovery and their potential targets leading towards a better quality of life and human welfare.Â
Distress, anxiety, and depression in cancer patients undergoing chemotherapy
BACKGROUND: Chemotherapy for cancer is an intense and cyclic treatment associated with number of side-effects. The present study evaluated the effect of chemotherapy on distress, anxiety and depression. PATIENTS AND METHODS: A total of 117 patients were evaluated by using distress inventory for cancer (DIC2) and hospital anxiety and depression scale (HADS). Majority of the patients were taking chemotherapy for solid tumors (52; 44.4%). RESULTS: The mean distress score was 24, 18 (15.38%) were found to have anxiety while 19 (16.23%) had depression. High social status was the only factor found to influence distress while female gender was the only factor found to influence depression in the present study. CONCLUSION: The study highlights high psychological morbidity of cancer patients and influence of gender on depression. Construct of distress as evaluated by DIC 2 may have a possible overlap with anxiety
Acquisition of Chemoresistance in Gliomas Is Associated with Increased Mitochondrial Coupling and Decreased ROS Production
Temozolomide (TMZ) is an alkylating agent used for treating gliomas. Chemoresistance is a severe limitation to TMZ therapy; there is a critical need to understand the underlying mechanisms that determine tumor response to TMZ. We recently reported that chemoresistance to TMZ is related to a remodeling of the entire electron transport chain, with significant increases in the activity of complexes II/III and cytochrome c oxidase (CcO). Moreover, pharmacologic and genetic manipulation of CcO reverses chemoresistance. Therefore, to test the hypothesis that TMZ-resistance arises from tighter mitochondrial coupling and decreased production of reactive oxygen species (ROS), we have assessed mitochondrial function in TMZ-sensitive and -resistant glioma cells, and in TMZ-resistant glioblastoma multiform (GBM) xenograft lines (xenolines). Maximum ADP-stimulated (state 3) rates of mitochondrial oxygen consumption were greater in TMZ-resistant cells and xenolines, and basal respiration (state 2), proton leak (state 4), and mitochondrial ROS production were significantly lower in TMZ-resistant cells. Furthermore, TMZ-resistant cells consumed less glucose and produced less lactic acid. Chemoresistant cells were insensitive to the oxidative stress induced by TMZ and hydrogen peroxide challenges, but treatment with the oxidant L-buthionine-S,R-sulfoximine increased TMZ-dependent ROS generation and reversed chemoresistance. Importantly, treatment with the antioxidant N-acetyl-cysteine inhibited TMZ-dependent ROS generation in chemosensitive cells, preventing TMZ toxicity. Finally, we found that mitochondrial DNA-depleted cells (ρ°) were resistant to TMZ and had lower intracellular ROS levels after TMZ exposure compared with parental cells. Repopulation of ρ° cells with mitochondria restored ROS production and sensitivity to TMZ. Taken together, our results indicate that chemoresistance to TMZ is linked to tighter mitochondrial coupling and low ROS production, and suggest a novel mitochondrial ROS-dependent mechanism underlying TMZ-chemoresistance in glioma. Thus, perturbation of mitochondrial functions and changes in redox status might constitute a novel strategy for sensitizing glioma cells to therapeutic approaches
The total antioxidant content of more than 3100 foods, beverages, spices, herbs and supplements used worldwide
Background: A plant-based diet protects against chronic oxidative stress-related diseases. Dietary plants contain variable chemical families and amounts of antioxidants. It has been hypothesized that plant antioxidants may contribute to the beneficial health effects of dietary plants. Our objective was to develop a comprehensive food database consisting of the total antioxidant content of typical foods as well as other dietary items such as traditional medicine plants, herbs and spices and dietary supplements. This database is intended for use in a wide range of nutritional research, from in vitro and cell and animal studies, to clinical trials and nutritional epidemiological studies. Methods: We procured samples from countries worldwide and assayed the samples for their total antioxidant content using a modified version of the FRAP assay. Results and sample information (such as country of origin, product and/or brand name) were registered for each individual food sample and constitute the Antioxidant Food Table. Results: The results demonstrate that there are several thousand-fold differences in antioxidant content of foods. Spices, herbs and supplements include the most antioxidant rich products in our study, some exceptionally high. Berries, fruits, nuts, chocolate, vegetables and products thereof constitute common foods and beverages with high antioxidant values. Conclusions: This database is to our best knowledge the most comprehensive Antioxidant Food Database published and it shows that plant-based foods introduce significantly more antioxidants into human diet than non-plant foods. Because of the large variations observed between otherwise comparable food samples the study emphasizes the importance of using a comprehensive database combined with a detailed system for food registration in clinical and epidemiological studies. The present antioxidant database is therefore an essential research tool to further elucidate the potential health effects of phytochemical antioxidants in diet
Region-Specific Expression of Mitochondrial Complex I Genes during Murine Brain Development
Mutations in the nuclear encoded subunits of mitochondrial complex I (NADH:ubiquinone oxidoreductase) may cause circumscribed cerebral lesions ranging from degeneration of the striatal and brainstem gray matter (Leigh syndrome) to leukodystrophy. We hypothesized that such pattern of regional pathology might be due to local differences in the dependence on complex I function. Using in situ hybridization we investigated the relative expression of 33 nuclear encoded complex I subunits in different brain regions of the mouse at E11.5, E17.5, P1, P11, P28 and adult (12 weeks). With respect to timing and relative intensity of complex I gene expression we found a highly variant pattern in different regions during development. High average expression levels were detected in periods of intense neurogenesis. In cerebellar Purkinje and in hippocampal CA1/CA3 pyramidal neurons we found a second even higher peak during the period of synaptogenesis and maturation. The extraordinary dependence of these structures on complex I gene expression during synaptogenesis is in accord with our recent findings that gamma oscillations – known to be associated with higher cognitive functions of the mammalian brain – strongly depend on the complex I activity. However, with the exception of the mesencephalon, we detected only average complex I expression levels in the striatum and basal ganglia, which does not explain the exquisite vulnerability of these structures in mitochondrial disorders
Variation in Phenotype, Parasite Load and Male Competitive Ability across a Cryptic Hybrid Zone
BackgroundMolecular genetic studies are revealing an increasing number of cryptic lineages or species, which are highly genetically divergent but apparently cannot be distinguished morphologically. This observation gives rise to three important questions: 1) have these cryptic lineages diverged in phenotypic traits that may not be obvious to humans; 2) when cryptic lineages come into secondary contact, what are the evolutionary consequences: stable co-existence, replacement, admixture or differentiation and 3) what processes influence the evolutionary dynamics of these secondary contact zones?Methodology/principal findingsTo address these questions, we first tested whether males of the Iberian lizard Lacerta schreiberi from two highly genetically divergent, yet morphologically cryptic lineages on either side of an east-west secondary contact could be differentiated based on detailed analysis of morphology, coloration and parasite load. Next, we tested whether these differences could be driven by pre-copulatory intra-sexual selection (male-male competition). Compared to eastern males, western males had fewer parasites, were in better body condition and were more intensely coloured. Although subtle environmental variation across the hybrid zone could explain the differences in parasite load and body condition, these were uncorrelated with colour expression, suggesting that the differences in coloration reflect heritable divergence. The lineages did not differ in their aggressive behaviour or competitive ability. However, body size, which predicted male aggressiveness, was positively correlated with the colour traits that differed between genetic backgrounds.Conclusions/significanceOur study confirms that these cryptic lineages differ in several aspects that are likely to influence fitness. Although there were no clear differences in male competitive ability, our results suggest a potential indirect role for intra-sexual selection. Specifically, if lizards use the colour traits that differ between genetic backgrounds to assess the size of potential rivals or mates, the resulting fitness differential favouring western males could result in net male-mediated gene flow from west to east across the current hybrid zone.Devi Stuart-Fox, Raquel Godinho, Joëlle Goüy de Bellocq, Nancy R. Irwin, José Carlos Brito, Adnan Moussalli, Pavel Široký, Andrew F. Hugall and Stuart J. E. Bair
Modes of Aβ toxicity in Alzheimer’s disease
Alzheimer’s disease (AD) is reaching epidemic proportions, yet a cure is not yet available. While the genetic causes of the rare familial inherited forms of AD are understood, the causes of the sporadic forms of the disease are not. Histopathologically, these two forms of AD are indistinguishable: they are characterized by amyloid-β (Aβ) peptide-containing amyloid plaques and tau-containing neurofibrillary tangles. In this review we compare AD to frontotemporal dementia (FTD), a subset of which is characterized by tau deposition in the absence of overt plaques. A host of transgenic animal AD models have been established through the expression of human proteins with pathogenic mutations previously identified in familial AD and FTD. Determining how these mutant proteins cause disease in vivo should contribute to an understanding of the causes of the more frequent sporadic forms. We discuss the insight transgenic animal models have provided into Aβ and tau toxicity, also with regards to mitochondrial function and the crucial role tau plays in mediating Aβ toxicity. We also discuss the role of miRNAs in mediating the toxic effects of the Aβ peptide
Alzheimer's Disease susceptibility genes APOE and TOMM40, and hippocampal volumes in the Lothian birth cohort 1936
The APOE ε and TOMM40 rs10524523 (‘523’) variable length poly-T repeat gene loci have been significantly and independently associated with Alzheimer’s disease (AD) related phenotypes such as age of clinical onset. Hippocampal atrophy has been significantly associated with memory impairment, a characteristic of AD. The current study aimed to test for independent effects of APOE ε and TOMM40 ‘523’ genotypes on hippocampal volumes as assessed by brain structural MRI in a relatively large sample of community-dwelling older adults. As part of a longitudinal study of cognitive ageing, participants in the Lothian Birth Cohort 1936 underwent genotyping for APOE ε2/ε3/ε4 status and TOMM40 ‘523’ poly-T repeat length, and detailed structural brain MRI at a mean age of 72.7 years (standard deviation = 0.7, N range = 624 to 636). No significant effects of APOE ε or TOMM40 523 genotype were found on hippocampal volumes when analysed raw, or when adjusted for either intracranial or total brain tissue volumes. In summary, in a large community-dwelling sample of older adults, we found no effects of APOE ε or TOMM40 523 genotypes on hippocampal volumes. This is discrepant with some previous reports of significant association between APOE and left/right hippocampal volumes, and instead echoes other reports that found no association. Previous significant findings may partly reflect type 1 error. Future studies should carefully consider: 1) their specific techniques in adjusting for brain size; 2) assessing more detailed sub-divisions of the hippocampal formation; and 3) testing whether significant APOE-hippocampal associations are independent of generalised brain atrophy
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