47 research outputs found
Sonication, Vacuum Infiltration and Thiol Compounds Enhance the Agrobacterium-Mediated Transformation Frequency of Withania somnifera (L.) Dunal
Factors influencing podophyllotoxin production in adventitious root culture of Podophyllum hexandrum Royle
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.University of Pretoria and National Research Foundation (NRF), South Africa for Vice-Chancellor and Free-standing Postdoctoral Fellowshipshttp://link.springer.com/journal/13562hb201
L-Dopa production and antioxidant activity in Hybanthus enneaspermus (L.) F. Muell regeneration
Production of Withanolides from Cell and Organ Cultures of Withania somnifera (L.) Dunal
Enhanced Biosynthesis of Withanolides by Elicitation and Precursor Feeding in Cell Suspension Culture of Withania somnifera (L.) Dunal in Shake-Flask Culture and Bioreactor
Oral silibinin inhibits lung tumor growth in athymic nude mice and forms a novel chemocombination with doxorubicin targeting nuclear factor κB-mediated inducible chemoresistance
The acute and cumulative dose-related toxicity and drug resistance, mediated via nuclear factor κB (NFκB), of anthracycline anticancer drugs pose a major problem in cancer chemotherapy. Here, we report that oral silibinin (a flavanone) suppresses human non-small-cell lung carcinoma A549 xenograft growth (P = 0.003) and enhances the therapeutic response (P < 0.05) of doxorubicin in athymic BALB/c nu/nu mice together with a strong prevention of doxorubicin-caused adverse health effects. Immunohistochemical analyses of tumors showed that silibinin and doxorubicin decrease (P < 0.001) proliferation index and vasculature and increase (P < 0.001) apoptosis; these effects were further enhanced (P < 0.001) in combination treatment. Pharmacologic dose of silibinin (60 μmol/L) achieved in animal study was biologically effective (P < 0.01 to 0.001, growth inhibition and apoptosis) in vitro in A549 cell culture together with an increased efficacy (P < 0.05 to 0.001) in doxorubicin (25 nmol/L) combination. Furthermore, doxorubicin increased NFκB DNA binding activity as one of the possible mechanisms for chemoresistance in A549 cells, which was inhibited by silibinin in combination treatment. Consistent with this, silibinin inhibited doxorubicin-caused increased translocation of p65 and p50 from cytosol to nucleus. Silibinin also inhibited cyclooxygenase-2, an NFκB target, in doxorubicin combination. These findings suggest that silibinin inhibits in vivo lung tumor growth and reduces systemic toxicity of doxorubicin with an enhanced therapeutic efficacy most likely via an inhibition of doxorubicin-induced chemoresistance involving NFκB signaling