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O P Sharma - One of the best experts on this subject based on the ideXlab platform.

  • fungal degradation of lantadene a the Pentacyclic Triterpenoid hepatotoxin of lantana plant
    International Biodeterioration & Biodegradation, 2001
    Co-Authors: Anita Singh, O P Sharma, Tej K Bhat, Surinder K Vats, Sudarshan Ojha
    Abstract:

    Seven white-rot fungi, known to degrade complex biomolecules and xenobiotics were used for investigation on biodegradation of lantadene A (LA), the bioactive Pentacyclic Triterpenoid of Lantana camara. Pleurotus sajor-caju and Merulius tremellosus PRL-2845 did not degrade LA. Trametes versicolor MTCC-138, Heterobasidion annosum MTCC-146, Phellinus pini RAB-83-19, Pleurotus ostreatus MTCC-142 and Phlebia radiata 2 utilized LA to the extent of 11-15.7%. This is the first report on the fungal degradation of a Pentacyclic Triterpenoid.

  • biotransformation of lantadenes the Pentacyclic Triterpenoid hepatotoxins of lantana plant in guinea pig
    Toxicon, 2000
    Co-Authors: Sarita Sharma, O P Sharma, Bhupinder Singh, Tej K Bhat
    Abstract:

    Oral administration of lantana (Lantana camara var. aculeata) leaf powder to guinea pigs at a dose of 6 g/ kg body weight elicited cholestasis. The animals were euthanized 48 h after dosing. Liver homogenates, bile, gall bladder, blood, urine, contents of gastrointestinal tract (GIT) and faeces were analysed for the principal hepatotoxin in lantana leaves viz. lantadene A (LA), its congeners and biotransformation products, using high performance liquid chromatographic technique. Lantadenes could not be detected in liver, bile, gall bladder, blood and urine samples. LA and lantadene B (LB), their derivatives reduced lantadene A (RLA), reduced lantadene B (RLB) and two unidentified metabolites could be detected in the contents of lower GIT and faeces. In vitro incubation of lantana leaf powder with guinea pig caecal contents under anaerobic conditions elicited biotransformation of LA and LB to RLA and RLB, respectively. On the other hand, incubation of lantana leaf powder with cattle rumen liquor under anaerobic conditions did not elicit biotransformation of lantadenes.

  • disposition of lantadene a the Pentacyclic Triterpenoid hepatotoxin orally administered to guinea pigs
    Toxicology Letters, 1999
    Co-Authors: Sarita Sharma, O P Sharma, Rajinder K Dawra, Tej K Bhat
    Abstract:

    Lantadene A (LA) administered orally to guinea pigs elicited cholestasis. LA could not be detected in liver, bile, gall bladder, blood and urine. LA and its biotransformation product reduced lantadene A (RLA) could be detected in caecum, large intestine, and faeces. In vitro incubation of LA with liver homogenates under aerobic and anaerobic conditions did not elicit its biotransformation to RLA. On the other hand, in vitro incubation of LA with guinea pig caecal and large intestinal contents under anaerobic conditions elicited conversion of LA to RLA. This is the first report of the biotransformation of LA in the animal system.

  • biodegradation of lantadene a the Pentacyclic Triterpenoid hepatotoxin by pseudomonas pickettii
    Letters in Applied Microbiology, 1997
    Co-Authors: O P Sharma, Rajinder K Dawra, A K Datta, Sarbjit Singh Kanwar
    Abstract:

    A bacterial strain capable of biodegradation of lantadene A (22β-angeloyloxy-3-oxoolean-12-en-28-oic acid) has been isolated from soil using lantadene A as the sole carbon source. The organism is rod shaped, Gram negative, motile and has been identified as Pseudomonas pickettii. This is the first report of the biodegradation of a Pentacyclic Triterpenoid.

  • molecular structure polymorphism and toxicity of lantadene a the Pentacyclic Triterpenoid from the hepatotoxic plant lantana camara
    Journal of Biochemical Toxicology, 1991
    Co-Authors: O P Sharma, Rajinder K Dawra, Vasantha Pattabhi
    Abstract:

    : Lantadene A (22 beta-angeloyloxy-3-oxo-olean-12-en-28-oic acid), a Pentacyclic Triterpenoid compound from lantana (Lantana camara) leaves has been obtained in two polymorphic forms I and II. Form I had white, fluffy, and rod-shaped uniform crystals. Form II particles were irregular, shining, and polyhedral. The two forms differed in melting behavior. The powder x-ray diffraction of form I showed sharp peaks whereas from II did not contain distinct peaks. From single-crystal three-dimensional x-ray structure determination, the molecular structure of form I has been established. A/B and B/C rings of the molecule are trans fused while D/E rings are cis fused. The packing of the molecule is stabilized by hydrogen bonding. Form I of lantadene A was non-toxic to guinea pigs on oral administration. Form II induced ictericity and toxicity associated with decrease in feed intake and fecal output, hepatomegaly, increase in plasma bilirubin, and acid phosphatase activity.

Tej K Bhat - One of the best experts on this subject based on the ideXlab platform.

  • fungal degradation of lantadene a the Pentacyclic Triterpenoid hepatotoxin of lantana plant
    International Biodeterioration & Biodegradation, 2001
    Co-Authors: Anita Singh, O P Sharma, Tej K Bhat, Surinder K Vats, Sudarshan Ojha
    Abstract:

    Seven white-rot fungi, known to degrade complex biomolecules and xenobiotics were used for investigation on biodegradation of lantadene A (LA), the bioactive Pentacyclic Triterpenoid of Lantana camara. Pleurotus sajor-caju and Merulius tremellosus PRL-2845 did not degrade LA. Trametes versicolor MTCC-138, Heterobasidion annosum MTCC-146, Phellinus pini RAB-83-19, Pleurotus ostreatus MTCC-142 and Phlebia radiata 2 utilized LA to the extent of 11-15.7%. This is the first report on the fungal degradation of a Pentacyclic Triterpenoid.

  • biotransformation of lantadenes the Pentacyclic Triterpenoid hepatotoxins of lantana plant in guinea pig
    Toxicon, 2000
    Co-Authors: Sarita Sharma, O P Sharma, Bhupinder Singh, Tej K Bhat
    Abstract:

    Oral administration of lantana (Lantana camara var. aculeata) leaf powder to guinea pigs at a dose of 6 g/ kg body weight elicited cholestasis. The animals were euthanized 48 h after dosing. Liver homogenates, bile, gall bladder, blood, urine, contents of gastrointestinal tract (GIT) and faeces were analysed for the principal hepatotoxin in lantana leaves viz. lantadene A (LA), its congeners and biotransformation products, using high performance liquid chromatographic technique. Lantadenes could not be detected in liver, bile, gall bladder, blood and urine samples. LA and lantadene B (LB), their derivatives reduced lantadene A (RLA), reduced lantadene B (RLB) and two unidentified metabolites could be detected in the contents of lower GIT and faeces. In vitro incubation of lantana leaf powder with guinea pig caecal contents under anaerobic conditions elicited biotransformation of LA and LB to RLA and RLB, respectively. On the other hand, incubation of lantana leaf powder with cattle rumen liquor under anaerobic conditions did not elicit biotransformation of lantadenes.

  • disposition of lantadene a the Pentacyclic Triterpenoid hepatotoxin orally administered to guinea pigs
    Toxicology Letters, 1999
    Co-Authors: Sarita Sharma, O P Sharma, Rajinder K Dawra, Tej K Bhat
    Abstract:

    Lantadene A (LA) administered orally to guinea pigs elicited cholestasis. LA could not be detected in liver, bile, gall bladder, blood and urine. LA and its biotransformation product reduced lantadene A (RLA) could be detected in caecum, large intestine, and faeces. In vitro incubation of LA with liver homogenates under aerobic and anaerobic conditions did not elicit its biotransformation to RLA. On the other hand, in vitro incubation of LA with guinea pig caecal and large intestinal contents under anaerobic conditions elicited conversion of LA to RLA. This is the first report of the biotransformation of LA in the animal system.

Krystian Marszalek - One of the best experts on this subject based on the ideXlab platform.

  • ursolic acid a Pentacyclic Triterpenoid with a wide spectrum of pharmacological activities
    Molecules, 2015
    Co-Authors: łukasz Woźniak, Sylwia Skąpska, Krystian Marszalek
    Abstract:

    Ursolic acid (UA) is a natural terpene compound exhibiting many pharmaceutical properties. In this review the current state of knowledge about the health-promoting properties of this widespread, biologically active compound, as well as information about its occurrence and biosynthesis are presented. Particular attention has been paid to the application of ursolic acid as an anti-cancer agent; it is worth noticing that clinical tests suggesting the possibility of practical use of UA have already been conducted. Amongst other pharmacological properties of UA one can mention protective effect on lungs, kidneys, liver and brain, anti-inflammatory properties, anabolic effects on skeletal muscles and the ability to suppress bone density loss leading to osteoporosis. Ursolic acid also exhibits anti-microbial features against numerous strains of bacteria, HIV and HCV viruses and Plasmodium protozoa causing malaria.

Jeen Woo Park - One of the best experts on this subject based on the ideXlab platform.

  • Ursolic acid sensitizes prostate cancer cells to TRAIL-mediated apoptosis
    Biochimica et Biophysica Acta - Molecular Cell Research, 2013
    Co-Authors: Seoung Woo Shin, Jeen Woo Park
    Abstract:

    Prostate cancer is one of the most commonly occurring malignancies in men, and because existing treatments are not able to manage this neoplasm adequately, novel approaches are needed. Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has strong antitumor activity via the induction of apoptotic cell death in a wide range of tumor cell types and has negligible toxicity to most normal cells, some prostate carcinoma cells are resistant to the apoptotic effects of TRAIL. Therefore, combinatorial approaches with TRAIL and different chemotherapeutic agents have been developed to overcome the resistance of cancer cells to TRAIL. Here, we investigated the sensitizing effects of ursolic acid (UA), a Pentacyclic Triterpenoid found in many plants, on TRAIL-induced prostate cancer cell apoptosis. We found TRAIL-induced prostate cancer cells apoptosis was significantly enhanced by UA, and that UA induced CHOP-dependent DR5 up-regulation. This study shows the use of UA as a sensitizer for TRAIL-induced apoptotic cell death offers a promising means of enhancing the efficacy of TRAIL-based prostate cancer treatments. © 2012 Elsevier B.V.

  • Sensitization of ionizing radiation-induced apoptosis by ursolic acid
    Free radical research, 2012
    Co-Authors: S J Koh, K M Park, S. T. Kim, J K Tak, W S Nam, S. Y. Kim, Jeen Woo Park
    Abstract:

    Radiation therapy has been widely used for treating human cancers. However, cancer cells develop radioresistant phenotypes that decrease the efficacy of radiotherapy. Ionizing radiation (IR) induces the production of reactive oxygen species, which play an important role in apoptotic cell death. Therefore, radiation therapy combined with a sensitizer, which modulates cellular redox status, has the potential to enhance therapeutic efficacy in a variety of human cancers. Here, we investigated the radiosensitizing effects of ursolic acid (UA), a Pentacyclic Triterpenoid found in rosemary and holy basil. IR-induced apoptosis in cancer cell lines such as DU145, CT26 and B16F10 was significantly enhanced by UA, as reflected by DNA fragmentation, cellular redox status, mitochondrial dysfunction and modulation of apoptotic marker proteins. Additionally, UA combined with IR was also effective for inhibiting tumorigenesis in B16F10 melanoma cells implanted into mice. Taken together, these results suggest that applying UA together with IR may be an effective combination modality for treating cancer.

Krystian Marszałek - One of the best experts on this subject based on the ideXlab platform.

  • Ursolic Acid — A Pentacyclic Triterpenoid with a Wide Spectrum of Pharmacological Activities Ursolic Acid — A Pentacyclic Triterpenoid with a Wide Spectrum of Pharmacological Activities
    Molecules, 2015
    Co-Authors: Sylwia Skapska, Krystian Marszałek
    Abstract:

    Ursolic acid (UA) is a natural terpene compound exhibiting many pharmaceutical Received: 3 July 2015 ; Accepted: 23 September 2015 ; Published: Academic Editor: Fernando Albericio properties. In this review the current state of knowledge about the health-promoting properties Department of Fruit and Vegetable Product Technology, Institute of Agricultural and Food Biotechnology, of this widespread, biologically active compound, as well as information about its occurrence and 36 Rakowiecka Street, 02-532 Warsaw, Poland; skapska@ibprs.pl (S.S.); marszalek@ibprs.pl (K.M.) biosynthesis are presented. Particular attention has been paid to the application of ursolic acid as * Correspondence: lukasz.wozniak@ibprs.pl; Tel.: +48-226-063-604; Fax: +48-228-490-426 an anti-cancer agent; it is worth noticing that clinical tests suggesting the possibility of practical use Abstract: Ursolic acid (UA) is a natural terpene compound exhibiting many pharmaceutical of UA have already been conducted. Amongst other pharmacological properties of UA one can properties. In this review the current state of knowledge about the health-promoting properties of mention protective effect on lungs, kidneys, liver and brain, anti-inflammatory properties, anabolic this widespread, biologically active compound, as well as information about its occurrence and effects on skeletal muscles and the ability to suppress bone density loss leading to osteoporosis. biosynthesis are presented. Particular attention has been paid to the application of ursolic acid as an anti-cancer agent; it is worth noticing that clinical tests suggesting the possibility of practical use of Ursolic acid also exhibits anti-microbial features against numerous strains of bacteria, HIV andHCV UA have already been conducted. Amongst other pharmacological properties of UA one can mention viruses and Plasmodium protozoa causing malaria