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Momordica dioica is a perennial, dioecious, cucurbitaceous climbing creeper (commonly known as kakrol, spiny gourd or teasle gourd). It is native to Asia with extensive distribution in India and Bangladesh. It is used not only as preventive and curative agent for various diseases but also as vegetable with a significant nutritional value over thousands of years. This review aims to take an attempt to evaluate the phytochemical, ethnobotanical, phytotherapeutical and pharmacological properties of kakrol according to the view of traditional medicinal plant based treatment including ayurveda along with recent scientific observations. Kakrol is considered as an underutilized vegetable, although having significant presence of certain compounds containing higher nutritional value than many frequently consumed vegetables. Moreover, as a traditional medicinal plant, it is still potential for its phytochemical components that increase the demand of further extensive evaluation to justify its other therapeutical roles. Therefore, this effort will be helpful to researchers who interested to disclose the unjustified phytotherapeutical role of Momordica dioica.

The heterogeneous nuclear ribonucleoprotein C1/C2 is one of the most abundant proteins in the nucleus, and shown to have roles in cellular differentiation and proliferation through post-transcriptional regulations of certain mRNA species. We studied its role in stress response using siRNA mediated knockdown approach in HeLa cells. Upon transient transfection with plasmid encoding siRNA, the cells showed increased sensitivities to various chemical agents, namely H(2)O(2, )paraquat, camptothecin, ICRF-193 and halogenated deoxyuridines. These results demonstrate that hnRNP C1/C2 is involved in maintenance of cellular homeostasis besides cellular differentiation and proliferation.

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Ayurveda is a holistic medical system of traditional medicine, and Triphala is one of the most popular formulations in Ayurveda. Triphala is composed of three kinds of herb, Terminalia chebula, Terminalia bellirica, and Emblica officinalis. Since Triphala is shown to exhibit a protective activity against ionizing radiation in mice, we investigated its activity in HeLa cells. We found that Triphala showed the protective effects against X-radiation and bleomycin, both of which generate DNA strand breaks, in HeLa cells. Further, Triphala efficiently eliminated reactive oxygen species (ROS) in HeLa cells. Thus, the antioxidant activity of Triphala would likely play a role in its protective actions against X-radiation and bleomycin because both agents damage DNA through the generation of ROS. These observations suggested that the radioprotective activity of Triphala can be, at least partly, studied with the cells cultured in vitro. The simple bioassay system with human cultured cells would facilitate the understanding of the molecular basis for the beneficial effects of Triphala.

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To analyze the relationship between resistance to oxidative stress and longevity, we isolated three novel paraquat-resistant mutants, mev-5, mev-6, and mev-7, from the nematode Caenorhabditis elegans. They all showed the Dyf (defective in dye filling) phenotype, but not always resistance to heat or UV. Life-span extension was observed only in the mev-5 mutant at 26 C. These results indicate that longevity is uncoupled with the phenotype of paraquat resistance.Key words: Caenorhabditis elegans; oxidative stress; paraquat; aging; Dyf A number of hypotheses have been presented to account for the mechanism of aging. The free radical hypothesis of aging was first mentioned by Harman in the mid-1950s, 1) and since then has drawn much attention. Among the free radicals, reactive oxygen species (ROS) are most notable because they are generated in normal metabolic processes and damage cellular components such as proteins, DNA, and lipids. The resulting damage is thought to cause cellular dysfunction and eventually to lead to senescence. Animals have evolved various defense mechanisms against ROS, 2) but they appear to be far from perfect. Accumulating genetic evidence from model organisms such as the nematode, fruit fly, and mouse indicates a positive relationship between the longevity of mutant individuals and their capacity to resist oxidative stress. 3)But, much remains to be elucidated as regards defense mechanisms against ROS even in model organisms.To assess the above relationship, we employed genetic analysis using the nematode C. elegans as a model system, because it has been proved to be extremely useful for identifying responsible genes in mutants. We used paraquat (methyl viologen), which generates superoxide anions in cells, as an agent to isolate mutants with resistance to oxidative stress. 4) We mutagenized wild-type N2 worms with ethyl-methansulfonate and screened them by resistance to paraquat.We isolated three novel mutants, designated mev-5 (qa5005), mev-6 (qa5006), and mev-7 (qa5007). Their paraquat-resistant traits were all recessive and inherited by progeny in a Mendelian fashion. Their mutations were cleaned by back-crossing to N2 worms five times for subsequent analysis. Genetic analysis revealed that mev-5, mev-6, and mev-7 were concordant with the genetic markers dpy-11, dpy-1, and dpy-5 located on LG V, III, and I respectively. To map the genes regionally, three-factor-cross experiments were carried out, and the following results were obtained: mev-5 (4/4) (rol-4 unc-76), unc-42 (3/6) mev-5 (3/6) lon-3, (unc-45 dpy-1) (9/ 9) mev-6, dpy-1 (3/9) mev-6 (6/9) unc-32, dpy-1 (3/14) mev-6 (11/14) unc-93, (dpy-5 unc-37) (5/5) mev-7, dpy-14 (8/12) mev-7 (4/12) unc-29, mev-7 (7/7) (unc-29 dpy-24), (unc-40 bli-4) (2/2) mev-7 (Fig. 1A).Sensitivity to paraquat in the mev-mutants was determined as described previously.5) In brief, eggs were placed and incubated on plates containing various concentration of paraquat for 5 d, and the percentage of worms that reached adulthood was determined. Wildtype N2 worms h...

Enforced expression of GNG11, G-protein subunit γ 11, induces cellular senescence in normal human diploid fibroblasts. We here examined the effect of the expression of GNG11 on the growth of immortalized human cell lines, and found that it suppressed the growth of SUSM-1 cells, but not of HeLa cells. We then compared these two cell lines to understand the molecular basis for the action of GNG11. We found that expression of GNG11 induced the generation of reactive oxygen species (ROS) and abnormal nuclear morphology in SUSM-1 cells but not in HeLa cells. Increased ROS generation by GNG11 would likely be caused by the down-regulation of the antioxidant enzymes in SUSM-1 cells. We also found that SUSM-1 cells, even under normal culture conditions, showed higher levels of ROS and higher incidence of abnormal nuclear morphology than HeLa cells, and that abnormal nuclear morphology was relevant to the increased ROS generation in SUSM-1 cells. Thus, SUSM-1 and HeLa cells showed differences in the regulation of ROS and nuclear morphology, which might account for their different responses to the expression of GNG11. Thus, SUSM-1 cells may provide a unique system to study the regulatory relationship between ROS generation, nuclear morphology, and G-protein signaling.