Department Of Botany

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Author: search.filters.author.Kumar, SanjeevHas files: Yes

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    Low temperature-induced aberrations in male and female reproductive organ development cause flower abortion in chickpea
    (Wiley, 2019) Kiran, Asha; Kumar, Sanjeev; Nayyar, Harsh; Sharma, Kamal Dev
    Chickpea (Cicer arietinum L.) is susceptible to low temperature (LT) at reproductive stage. LT causes flower abortion and delays pod set in chickpea until terminal drought becomes an issue, thereby decreasing yield potential. In chickpea, flower and anther/pollen development as well as LT?induced abnormalities on anther and pollen development are described inadequately. In the present manuscript, we report flower development stages, anther development stages, and aberrations in male gamete formation in chickpea under LT. Flower length was linearly correlated to flower and anther stages and can be used to predict these stages in chickpea. LT affected male gamete development in a flower/anther age?dependent manner where outcome ranged from no pollen formation to pollen sterility or no anther dehiscence to delayed dehiscence. In anthers, LT inhibited microsporogenesis, microgametogenesis, tapetum degeneration, breakage of septum and stomium, and induced pollen sterility. Whereas disruption of male function was the prime cause of abortion in flowers below vacuolated pollen stage, flower abortion was due to a combination of male and female reproductive functions in flowers with mature pollen. The study will help in elucidating mechanisms governing flower development, anther and pollen development, and tolerance/susceptibility to LT.
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    Vitex negundo and its medicinal value
    (Springer, 2018) Gill, Balraj Singh; Mehra, Richa; Navget; Kumar, Sanjeev
    Natural products are rich in several potent bioactive compounds, targeting complex network of proteins involved in various diseases. Vitex negundo (VN), commonly known as “chaste tree”, is an ethnobotanically important plant with enormous medicinal properties. Different species of Vitex vary in chemical composition, thus producing different phytochemicals. Several bioactive compounds have been extracted from leaves, seeds, roots in form of volatile oils, flavonoids, lignans, iridoids, terpenes, and steroids. These bioactive compounds exhibit anti-inflammatory, antioxidant, antidiabetic, anticancer, antimicrobial. VN is typically known for its role in the modulation of cellular events like apoptosis, cell cycle, motility of sperms, polycystic ovary disease, and menstrual cycle. VN, reportedly, perturbs many cancer-signaling pathways involving p-p38, p-ERK1/2, and p-JNK in LPS-elicited cells, N-terminal kinase (JNK), COX-1 pathways, MAPK, NF-κB, tumor necrosis factor α (TNF-α), Akt, mTOR, vascular endothelial growth factor, hypoxia-inducible factor (HIF-1α). Several bioactive compounds obtained from VN have been commercialized and others are under investigation. This is the first review presenting up-to-date information about the VN, its bioactive constituents and their mode of action.
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    S961, a biosynthetic insulin receptor antagonist, downregulates insulin receptor expression & suppresses the growth of breast cancer cells
    (Indian Council of Medical Research (ICMR), 2018) Sharma, PrateeK; Kumar, Sanjeev
    Background & objectives: Insulin resistance associated with hyperinsulinaemia and overexpression of insulin receptors (IRs) have been intricately linked to the pathogenesis and treatment outcomes of the breast carcinoma. Studies have revealed that upregulated expression of IRs in breast cancer pathogenesis regulates several aspects of the malignant phenotype, including cell proliferation and metastasis. This study was aimed to investigate the pivotal role of an IR antagonist S961 on IR signalling and other biological parameters in MCF-7, MDA-MB-231 and T47D cell lines. Methods: The effect of human insulin and S961 on growth, proliferation rate and clonogenic potential of breast cancer cells was evaluated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide] assay and clonogenic assay. The mRNA expression of IR isoforms (IR-A and IR-B) was measured in the breast carcinoma cells using quantitative PCR. Results: The study revealed that breast cancer cells predominantly expressed IR-A isoform and showed extensive growth and proliferation owing to IR overexpression. It was found that S961 downregulated the IRs (IR-A and IR-B) with nanomolar dose and efficiently blocked expression of IRs even in the presence of insulin. IR mRNA expression levels were significantly downregulated in the continued presence of S961. S961 also inhibited cellular proliferation and colony formation in breast tumour cells. Interpretation & conclusions: IR antagonist, S961 showed distinct antagonism in vitro and appeared to be a powerful therapeutic modality that might provide insight into the pathogenesis of impaired IR signalling.
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    Metformin inhibits human breast cancer cell growth by promoting apoptosis via a ROS-independent pathway involving mitochondrial dysfunction: pivotal role of superoxide dismutase (SOD)
    (Springer, 2018) Sharma, Prateek; Kumar, Sanjeev
    Purpose Despite a growing body of evidence indicating a potential efficacy of the anti-diabetic metformin as anti-cancer agent, the exact mechanism underlying this efficacy has remained largely unknown. Here, we aimed at assessing putative mechanisms associated with the ability of metformin to reduce the proliferation and migration of breast cancer cells. Methods A battery of in vitro assays including MTT, colony formation, NBT and scratch wound healing assays were performed to assess the viability, proliferation, anti-oxidative potential and migration of breast cancer-derived MCF-7, MDA-MB-231 and T47D cells, respectively. Reactive oxygen species (ROS) assays along with fluorescence microscopy were used to assess apoptotic parameters. Quantification of SOD, Bcl-2, Bax, MMPs, miR-21 and miR-155 expression was performed using qRT-PCR. Results We found that metformin inhibited the growth, proliferation and clonogenic potential of the breast cancer-derived cells tested. ROS levels were found to be significantly reduced by metformin and, concomitantly, superoxide dismutase (SOD) isoforms were found to be upregulated. Mitochondrial dysfunction was observed in metformin treated cells, indicating apoptosis. In metastatic MDA-MB-231 cells, migration was found to be suppressed by metformin through deregulation of the matrix metalloproteinases MMP-2 and MMP-9. The oncogenic microRNAs miR-21 and miR-155 were found to be downregulated by metformin, which may be correlated with the suppression of cell proliferation and/or migration. Conclusions Our data indicate that metformin may play a pivotal role in modulating the anti-oxidant system, including the SOD machinery, in breast cancer-derived cells. Our observations were validated by in silico analyses, indicating a close interaction between SOD and metformin. We also found that metformin may inhibit breast cancer-derived cell proliferation through apoptosis induction via the mitochondrial pathway. Finally, we found that metformin may modulate the pro-apoptotic Bax, anti-apoptotic Bcl-2, MMP-2, MMP-9, miR-21 and miR-155 expression levels. These findings may be instrumental for the clinical management and/or (targeted) treatment of breast cancer.
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    Identifying the preferred interaction mode of naringin with gold nanoparticles through experimental, DFT and TDDFT techniques: Insights into their sensing and biological applications
    (Royal Society of Chemistry, 2016) Singh, Baljinder; Rani, Monika; Singh, Janpreet; Moudgil, Lovika; Sharma, Prateek; Kumar, Sanjeev; Saini, G.S.S.; Tripathi, S.K.; Singh, Gurinder; Kaura, Aman
    In this work, the binding behaviour of naringin-a flavonoid with AuNPs is explained by combining experimental and theoretical approaches. We have systematically analysed the effect of temperature and concentration of naringin and gold (Au) in the formation of naringin stabilized Au nanoparticles (N-AuNPs). The interaction of naringin with gold nanoparticles (AuNPs) is investigated by various techniques such as UV-visible spectroscopy, TEM, FT-IR, XRD and gel electrophoresis. These studies indicate that naringin acts as a reducing and stabilizing agent. Further, we have modelled the two side chains of naringin with the functional groups [C10H7O2] and [C6H5O]-, and identified the lowest energy configurations of these groups with AuNPs with the help of density functional theory (DFT). The [C10H7O2]-Au13 has higher binding energy than [C6H5O]--Au13 and it is attributed to delocalized molecular orbitals in [C10H7O2], hence higher charge transfer to the Au13 cluster. On the basis of the resulting structures, we examine the optical properties using time-dependent density functional theory (TDDFT). We observe significant changes in the optical spectra of the representative structures of side chains with the AuNPs. The peak in the spectra of the Vis region of [C10H7O2]-Au13 undergoes a shift towards lower wavelength in comparison to [C6H5O]--Au13. Natural transition orbitals (NTOs) of hole and particle states of the [C10H7O2]-Au13 conjugate system are localized on [C10H7O2] and Au13, respectively, whereas for the [C6H5O]--Au13 both hole and particle states are localized on the Au13 cluster. These N-AuNPs show their applicability as a sensor for detecting aluminium ions (Al3+) in aqueous solution. These NPs are also found to be biocompatible with normal red blood cells and MDAMB-231 breast carcinoma cell lines, as evaluated from hemolysis and cytotoxicity assays. Thus, naringin offers non-toxic and bio friendly N-AuNPs, which are considered to be the best vehicle for drug release and other possible biomedical and sensing applications. ? 2016 The Royal Society of Chemistry.
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    Ganoderic Acid A Targeting ?-Catenin in Wnt Signaling Pathway: In Silico and In Vitro Study
    (Springer Berlin Heidelberg, 2018) Gill, Balraj Singh; Kumar, Sanjeev; Navgeet
    Wnt signaling pathways are the group of signaling transduction controlling the embryonic development, cell proliferation, cell migration, cell fate specification, and body axis pattern. Nuclear accumulation of ?-catenin in Wnt signaling is a widely recognized marker of poor cancer prognosis which regulates fat and glucose metabolism. Ganoderic acid is a triterpene isolated from fungus Ganoderma lucidum renowned for its pharmacological effects. The present study revealed the mechanistic study of ?-catenin with 50 isoforms of ganoderic acid by molecular docking using Maestro 9.6 (Schr?dinger Inc) in Wnt signaling pathway. Molecular docking reveals the binding interaction of ?-catenin and ganoderic acid A with GScore (?9.44), kcal/mol, lipophilic EvdW (?2.86), electro (?0.72), Glide emodel (?50.401), MM-GBSA (?87.441), H bond (?1.91) with Lys 180 and Asn 220 residues involved in hydrogen bonding. Qikprop analyzed the absorption, distribution, metabolism, excretion, and toxicity and confirmed that most of the isoforms satisfies Lipinski rule but needs little modifications in their structure. The ganoderic acid A is the best-docked isoforms which inhibits the proliferation, viability, and intracellular ROS of pancreatic cancer RIN-5F cells in a dose-dependent manner. ? 2016, International Association of Scientists in the Interdisciplinary Areas and Springer-Verlag Berlin Heidelberg.
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    Amino acid functionalized zinc oxide nanostructures for cytotoxicity effect and hemolytic behavior: Theoretical and experimental studies
    (Elsevier Ltd, 2017) Singh, Satvinder; Singh, Baljinder; Sharma, Prateek; Mittal, Anu; Kumar, Sanjeev; Saini, G.S.S.; Tripathi, S.K.; Singh, Gurinder; Kaura, Aman
    Blending of theoretical and experimental approach, provide an important strategy in designing the nanostructure at a microscopic level and helps in predicting the response of synthesized material towards inhibition of the growth of breast cancer cell. In this work, ab initio calculations using super cell approach are performed for three different amino acids (AAs)-Histidine (His), Arginine (Arg) and Aspartic acid (Asp) coated Zinc oxide (ZnO) nanostructures to explain the growth mechanism of nanoparticles (NPs) of different shapes. Based on the first principles calculations, we reveal that ZnO-AA (Arg and Asp) NPs results in rod like and ZnO-His NPs lead to tablet like configuration. Similar morphologies are fabricated using AAs through synthetic route. The effect of concentration ratio of reactants and pH has been studied. As synthesized samples, are characterized by using Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) and UV?Vis spectroscopy techniques. Based on the results, a plausible mechanism of formation of nanostructures has been proposed. The nanostructures with rod like morphology are found to be biocompatible with normal red blood cells and show cytotoxic effect as evaluated from hemolysis and cytotoxicity assays on breast (MCF-7, T47D, MDA-MB-231) & prostate cancer (PC-3) cell lines. ? 2017 Elsevier Ltd
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    Ganoderic acid, lanostanoid triterpene: a key player in apoptosis
    (Springer New York LLC, 2018) Gill, Balraj Singh; Navgeet; Mehra, Richa; Kumar, Vicky; Kumar, Sanjeev
    Cancer is a multifactorial disease, causing behavioral and metabolic alterations, leading to uncontrolled cell proliferation with collateral weakening of immune system. Crucial balance between cell proliferation and cell death determines the fate of a cell, which might progress towards survival or apoptosis. Apoptosis is a complex, programmed, and highly regulated process causing dramatic morphological and biochemical perturbations in the cellular machinery. Ganoderma lucidum is a basidiomycetes, polypore mushroom known for its pharmacological properties in cancer. The major bioconstituents in G. lucidum are terpenoids, polysaccharides, and proteins that target cancer-signaling factors like plasma membrane receptors proteins and adapter molecules. Of all constituents, the major terpenoid, i.e. Ganoderic acid is reported to interact with membrane receptors mainly, receptor tyrosine kinase (RTKs). Ganoderic acid interacts and modulates the signaling network in IR, IGFR-1, IGFR-2, VEGFR-1, VEFGR-2, and EGFR in cancer signaling pathways. It primarily targets NF-?B, RAS-MAPK, PI3K/Akt/mTOR, and cell cycle resulting in apoptosis. This review highlights the role of ganoderic acid in apoptosis and modulations of various signaling proteins in cancer. ? 2017, Springer Science+Business Media, LLC.
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    Triterpenes in cancer: significance and their influence
    (Springer Netherlands, 2016) Gill, Balraj Singh; Kumar, Sanjeev; Navgeet
    Natural products are enriched with numerous compounds with a broad spectrum of therapeutics indication suggesting the role of functional moieties as a core pharmacophore. This review highlights the role of triterpene in targeting signaling pathways in cancer. Advancement in cellular, biochemical, experimental, and computational approaches provides new insights into various pathways in cancer. In signaling network, triterpenes primarily target membrane receptors which control and modulates expression level of the biological responses. Triterpenes are immunomodulatory targeting nuclear factor kappa B, toll-like receptors, signal transducer and activator of transcription 3, and PI3K/Akt/mTOR. Triterpenes isolated from plants and fungus mainly focus on the process of apoptosis while other signaling areas in the cancer are still shrouded. Some of the triterpenes have already passed the clinical trial, whereas many more have been proven to yield effective results. This review would help the researchers to study the role of triterpenes in cancer, thus, helping them to discover and design efficacious therapeutics agents. ? 2016, Springer Science+Business Media Dordrecht.
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    Temperature-stratified screening of chickpea (Cicer arietinum L.) genetic resource collections reveals very limited reproductive chilling tolerance compared to its annual wild relatives
    (2012) Berger, J.D.; Kumar, Sanjeev; Nayyar, H.; Street, K. A.; Sandhu, J. S.; Henzell, J. M.; Kaur, J.; Clark, H.C.
    Low reproductive chilling tolerance in chickpea impairs ovule fertilization, delaying pod set, exposing the crop to terminal drought throughout much of its distribution range. Despite this realization, little progress has been made because of the limited genetic variation available to breeders. To address this issue a wide range of domesticated (n= 1762) and wild Cicer (n= 200) germplasm collected from sites stratified by flowering phase temperature was extensively field evaluated, and compared with Lupinus angustifolius, a well-adapted Mediterranean winter annual. Chilling tolerance was estimated by regressing the time interval between pod set and first flower against mean post-anthesis temperature. Field screening was augmented by smaller scale experiments evaluating the effects of contrasting post-anthesis temperature regimes on plant growth and productivity, pollen function and subsequent pod set in temperature-controlled cabinets.Chickpea was less chilling tolerant than its wild relatives, the flower-pod interval increasing curvi-linearly as sites became cooler, with a strong effects between 11 and 16. ?C, tailing off after 17.5. ?C, but remaining statistically significant. There is little useful variation for chilling tolerance within domesticated chickpea. Small, albeit statistically significant differences in pod set delay in chickpea collected from contrasting flowering phase habitats, were marginal compared to more tolerant species such as Cicer bijugum, Cicer judaicum and L. angustifolius, and to a lesser extent Cicer reticulatum, Cicer pinnatifidum, and Cicer echinospermum. No differences were observed between desi and kabuli types. Field screening identified robust chilling tolerance in a C. echinospermum accession that commenced podding earlier, at lower temperatures (10.0. ?C), and yielded 5 times more than Rupali, the most productive chickpea. Controlled temperature experiments confirmed that in contrast to chickpea, pollen germination, viability, frequency on the stigma surface and subsequent pod set were unaffected by low post-anthesis temperatures (13/7. ?C) in C. echinospermum and L. angustifolius. Our results indicate that chickpea is even more chilling sensitive than previously thought. Because C. echinospermum is inter-fertile with chickpea, it has considerable potential both as a donor of robust chilling tolerance and as an agent for investigating resistance mechanisms. ? 2011.