The regulation and role of NDRG2 during catabolic stress in skeletal muscle

Outcomes of these studies demonstrated novel role and regulation of skeletal muscle growth regulator, NDRG2. NDRG2 is highly expressed in chronic and diseased muscle conditions, defining its physiological role and function is required to determine whether it has a therapeutic potential to treat muscle atrophy

PREVALENCE AND ANTIMICROBIAL SUSCEPTIBILITY OF METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS AND COAGULASE-NEGATIVE STAPHYLOCOCCI IN A TERTIARY CARE HOSPITAL.

Background: Globally nosocomial infection is a major problem. Prevalence and antibiotic resistance of methicillin-resistant Staphylococcus aureus (MRSA) strains is reported to be increasing globally. MRSA and methicillin resistant coagulase negative staphylococci (MRCoNS) are the important agents causing nosocomial infections. Objective: The study was conducted to find out the prevalence rate of MRSA and MRCoNS and antibiotic susceptibility pattern. Materials and Methods: This was a retrospective study conducted from June 2011 to November 2012 in a tertiary care hospital in south India. All isolates were identified by Clinical and Laboratory Standards Institute (CLSI) guidelines and antibiotic susceptibility pattern determined by modified Kirby Bauer disc diffusion method. The information was recorded and analyzed using Microsoft Excel (2007 version). Results: A total of 210 Staphylococcus strains were isolated from various clinical samples, 180 were coagulase positive staphylococcus (CoPS) and 30 were coagulase negative staphylococcus (CoNS). Among 180 CoPS, 58 (32.22%) were Methicillin resistant and among CoNS, 12 (40%) were methicillin resistant. In MRSA maximum resistance was seen with oxacillin (93.2%) and least with vancomycin (3.5%). In MRCoNS maximum resistance was seen with oxacillin (91.7%) and least with vancomycin (0 %). Conclusion: There is need for continuous monitoring of the antimicrobial susceptibility pattern of methicillin staphylococcus aureus and methicillin resistant coagulase negative staphylococci for the selection of appropriate therapy, developing the antibiotic policy and for limiting the use of powerful antibiotics. Key words: Methicillin-resistant Staphylococcus aureus (MRSA), Methicillin resistant coagulase negative staphylococci, Vancomycin, Nosocomial infection, Susceptibility patter

In vitro propagation and withaferin A production in Withania ashwagandha, a rare medicinal plant of India

Withania ashwagandha, belonging to the family Solanaceae, is an important medicinal herb of India with restricted geographic distribution. It is a rich source of withaferin A (WA) and other bioactive withanolides. In the present study a rapid in vitro mass propagation protocol of W. ashwagandha was developed from nodal explants. Nodal explants were cultured on MS medium supplemented with various concentrations and combinations of plant growth regulators (PGRs). The highest number of regenerated shoots per ex-plant (33±2.7) and highest WA (13.4±1.15 mg/g of DW) production was obtained on MS medium supplemented with 5.0 μM 6-benzyladenine (BA) and 1.0 μM Kinetin (Kn). In vitro raised shoots were further rooted on half-strength MS medium containing 2.0 μM Indole-3-butyric acid (IBA) and analyzed forWA production. The rooted plantlets when transferred to poly bags in the greenhouse showed 90 % survival frequency. Levels of WA were higher in the in vitro and ex vitro derived shoot and root tissues as compared to field grown mother plants. In an attempt to further maximize WA production, shoot cultures were further grown in liquid MS medium supplemented with 5.0 μM 6-benzyladenine (BA) and 1.0 μM Kinetin (Kn). Root cultures were grown on half strength MS liquid medium fortified with 2.0 μMof IBA.WA production in the liquid cultures was significantly higher compared to the static composition of the same media. This protocol, first of its kind in this plant, can be successfully employed for conservation, proliferation and large-scale production of WA. The regenerated plants can also be used in traditional medicine as an alternative to naturally collected plants.University of Pretoria and National Research Foundation (NRF).South Africa Vice-Chancellor and Freestanding Postdoctoral Fellowship.http://link.springer.com/journal/12298hb201

MicroRNA-100 Reduced Fetal Bovine Muscle Satellite Cell Myogenesis and Augmented Intramuscular Lipid Deposition by Modulating IGF1R

Previously, microRNA-100 (miR-100) and its putative mRNA target, insulin-like growth factor receptor-1 (IGF1R) were identified as differentially and inversely expressed in bovine longissimus dorsi (LD) muscles with divergent intramuscular fat (IMF) content by our group. While IGF1R signaling is implicated in myogenesis and muscle lipid metabolism, the underlying regulatory mechanisms are poorly understood. In the present study, we aimed to investigate the regulation of IGF1R by miR-100 during bovine muscle satellite cell (BMSC) myogenesis and lipid deposition. MiR-100 was confirmed to target the IGF1R 3 '-untranslated region (3 '-UTR) by luciferase reporter assay. Furthermore, expression of miR-100 and IGF1R was reciprocal during BMSC differentiation, suggesting a crosstalk between the two. Correspondingly, miR-100 mimic (agomiR) suppressed the levels of IGF1R, PI3K/AKT pathway signaling, myogenic gene MYOG, muscle structural components MYH7 and MYH8, whereas the inhibitor (antagomiR) had no clear stimulating effects. The IGF1R inhibitor (BMS-754807) curtailed receptor levels and triggered atrophy in muscle myotubes but did not influence miR-100 expression. AgomiR increased oleic acid-induced lipid deposition in BMSC myotubes supporting its involvement in intramuscular fat deposition, while antagomiR had no effect. Moreover, mitochondrial beta-oxidation and long-chain fatty acid synthesis-related genes were modulated by agomiR addition. Our results demonstrate modulatory roles of miR-100 in BMSC development, lipid deposition, and metabolism and suggest a role of miR-100 in marbling characteristics of meat animals and fat oxidation in muscle.Peer reviewe

The Use of a Rabbit Model to Evaluate the Influence of Age on Excision Wound Healing

Background: The wound healing involves a highly co-ordinated cascade of cellular and immunological response over a period of time including coagulation, inflammation, granulation tissue formation, epithelialization, collagen synthesis and tissue remodeling. Wounds in aged heal more slowly than those in younger, mainly because of co morbidities that occurs as one ages. Present study is about the influence of age on wound healing. 1x1cm2 (100mm) wounds were created on the back of the animal. The animals were divided into two groups; one group had animals in the age group of 3-9 months while another group had animals in the age group of 15-21 months. Materials and Methods: 24 clinically healthy rabbits in the age group of 3-21 months were used as experimental animals and divided in two groups viz A and B. All experimental parameters i.e Excision wound model, Measurement of wound area, Protein extraction and estimation, Protein extraction and estimation and DNA extraction and estimation were done by standard methods. Results: The parameters studied were wound contraction, hydroxyproline, glucosamine, protein and DNA. Significant increase (p<0.005) in the hydroxyproline, glucosamine, protein and DNA and significant decrease in wound area (p<0.005) was observed in the age group of 3-9 months when compared to animals of age group of 15-21 months. Wound contraction together with hydroxyproline, glucosamine, protein and DNA estimations suggest that advance age results in retarded wound healing. Conclusion: The decrease wound contraction and accumulation of hydroxyproline, glucosamine, protein and DNA in group B animals may be associated with the reduction or delay in growth factors because of the advancing age

Enhanced production of withaferin-A in shoot cultures of Withania somnifera (L) Dunal

Withania somnifera (L) Dunal, commonly known as ashwagandha or Indian ginseng, is the source of large number of pharmacologically active withanolides. Withaferin-A (WS-3), a major withanolide of W. somnifera, has been proven to be an effective anti-cancer molecule. In this study, a liquid culture system for shoot proliferation, biomass accumulation and withaferin-A production of an elite accession (AGB002) of W. somnifera was investigated. The nodal explants cultured on Murashige and Skoog (MS) semi-solid medium supplemented with various concentrations of 6-benzyl adenine (BA) and Kinetin (Kn) elicited varied responses. The highest number of regenerated shoots per ex-plant (35 ± 3.25) and the maximum average shoot length (5.0 ± 0.25 cm) were recorded on MS medium supplemented with BA (5.0 μM). The shoots were further proliferated in half and full strength MS liquid medium supplemented with the same concentration BA. It was interesting to note that shoots cultured on MS half strength liquid medium fortified with 4 gL-1 FW (fresh weight) shoot inoculum mass derived from 5 week old nodal explants of W. somnifera showed highest accumulation of biomass and withaferin A content in 5 weeks. Withaferin A was produced in relatively high amounts (1.30 % and 1.10 % DW) in shoots cultured in half and full strength MS liquid media respectively as compared to natural field grown plants (0.85 % DW). A considerable amount of the withaferin A was also excreted in the culture medium. Successful proliferation of shoots in liquid medium and the synthesis of withaferin A in vitro opens new avenues for bioreactor scale-up and the large-scale production of the compound

Reproductive biology of Withania ashwagandha sp. novo (Solanaceae)

Withania ashwagandha Kaul (Solanaceae) is an annual plant species of immense medicinal importance. It is a repository of a large number of pharmacologically active secondary metabolites known as withanolides. Evidence for the delimitation of the species from W. somnifera has been provided by our group using multidisciplinary approaches. Knowledge of reproductive biology of medicinal plants is crucial for improvement, effective conservation and management plans to evolve genetically superior varieties. The present paper reports our findings on the floral biology, pollination behavior and breeding system of W. ashwagandha in natural populations grown at our experimental field under near natural conditions. Flowering (peak) takes place during April–July and anthesis occurs between 08:00 and 11:00 h. The period of stigma receptivity coincides with anther dehiscence. Fruit set on pollination treatments ranged from 90.8% (passive autogamy), 72% (assisted autogamy), 30.30% (xenogamy), and 56.50% (geitonogamy) through 50.40% (open pollination). Xenogamy brings about very low fruit set, seed-set and seed germination percentages. It is inferred that W. ashwagandha is predominantly an autogamous and self-compatible species. Self-compatibility is mainly accomplished due to close proximity of stigma and anthers. This work is the first report on the reproductive biology of W. ashwagandha and will be useful for conservation and development of improved varieties of this multipurpose herb.The author acknowledge the University of Pretoria for providing Vice-Chancellors Post Doctoral Fellowship.http://www.elsevier.com/locate/indcrophb201

Natural products as lead compounds in drug discovery

This review surveys the diversity of natural products (NPs) derived from terrestrial plants, micro-organisms, marine organisms and fungi used in the treatment of various diseases. A wide spectrum of compounds derived from these sources has been found to have many applications in the fields of medicine, pharmacy, and general biology. The enormous structural diversity of NPs and their medicinal significance has led researchers to predict that screening natural resources will generate new ‘lead’ compounds. It is well established that structural analogs with greater pharmacological activity and fewer side effects can be generated by molecular modification of the functional groups of such lead compounds. The compounds derived from various NP sources have been a basis for the development of clinically important agents active against various diseases, including taxol, vinblastine, vincristine, and topotecan, which are important anticancer agents in widespread clinical use. A number of other promising agents such as flavopiridol, combretastatin, betulinic acid, and silvesterol are in clinical or preclinical development. A large number of anti-infective agents in clinical use are also derived from NPs.University of Pretoriahttp://www.tandfonline.com/loi/ganp20hb201

Physiological studies and proteomic analysis for differentially expressed proteins and their possible role in the root of N-efficient rice (Oryza sativa L.)

The root proteome of nitrogen-efficient and nitrogen-inefficient rice cultivars was compared in this study in order to investigate the differential expression of proteins under deficient (1 mM), low (10 mM) and high (25 mM) levels of nitrogen (N). Nitrogen use efficiency (NUE) was assessed by biochemical assays such as N-uptake kinetics and activities of N-assimilation enzymes. Two-dimensional gel electrophoresis and MALDI–TOF–MS analysis resulted in the identification of 504 protein spots (210 and 294 spots in cvs. Rai Sudha and Munga Phool, respectively). A positive correlation was observed between physiological parameters and the concentration of a number of root proteins. Sixty-three spots showed a significant cultivar N-treatment effect on the level of expression. Functional aspects of eleven spots with major alterations in expression over control were critically analyzed. The data suggest that glutamine synthetase, cysteine proteinase inhibitor-I, porphobilinogen deaminase (fragment) and ferritin were involved in conferring N efficiency to the N-efficient rice cultivars/genotypes. Interestingly, these proteins are involved directly or indirectly in N assimilation. Such studies should help us in identifying and understanding the structural or functional protein(s) involved in the response to the level of nitrogen fertilization