Four new neuroprotective dihydropyranocoumarins from Angelica gigas.
Four new dihydropyranocoumarins were isolated from Angelica gigas roots through neuroprotective activity-guided isolation and were characterized as decursinol derivatives 4”-hydroxytigloyldecursinol (1), 4”-hydroxydecursin (2), (2”S,3”S)-epoxyangeloyldecursinol (3), and (2”R,3”R)-epoxyangeloyldecursinol (4), respectively. All four new dihydropyranocoumarins and major coumarin derivatives of A. gigas, decursinol and decursin, exhibited significant protective activity against glutamate-induced neurotoxicity when added to primary cultures of rat cortical cells at concentrations ranging from 0.1 to 10 microM.
J Nat Prod. 2005 Jan;68(1):56-9
Potent antiandrogen and androgen receptor activities of an Angelica gigas-containing herbal formulation: identification of decursin as a novel and active compound with implications for prevention and treatment of prostate cancer.
Androgen and androgen receptor (AR)-mediated signaling are crucial for the development of prostate cancer. Identification of novel and naturally occurring phytochemicals that target androgen and AR signaling from Oriental medicinal herbs holds exciting promises for the chemoprevention of this disease. In this article, we report the discovery of strong and long-lasting antiandrogen and AR activities of the ethanol extract of a herbal formula (termed KMKKT) containing Korean Angelica gigas Nakai (AGN) root and nine other Oriental herbs in the androgen-dependent LNCaP human prostate cancer cell model. The functional biomarkers evaluated included a suppression of the expression of prostate-specific antigen (PSA) mRNA and protein (IC50, approximately 7 microg/mL, 48-hour exposure) and an inhibition of androgen-induced cell proliferation through G1 arrest and of the ability of androgen to suppress neuroendocrine differentiation at exposure concentrations that did not cause apoptosis. Through activity-guided fractionation, we identified decursin from AGN as a novel antiandrogen and AR compound with an IC50 of approximately 0.4 microg/mL (1.3 micromol/L, 48-hour exposure) for suppressing PSA expression. Decursin also recapitulated the neuroendocrine differentiation induction and G1 arrest actions of the AGN and KMKKT extracts. Mechanistically, decursin in its neat form or as a component of AGN or KMKKT extracts inhibited androgen-stimulated AR translocation to the nucleus and down-regulated AR protein abundance without affecting the AR mRNA level. The novel antiandrogen and AR activities of decursin and decursin-containing herbal extracts have significant implications for the chemoprevention and treatment of prostate cancer and other androgen-dependent diseases.
Cancer Res. 2006 Jan 1;66(1):453-63
Blockade of nuclear factor-kappaB signaling pathway and anti-inflammatory activity of cardamomin, a chalcone analog from Alpinia conchigera.
Nuclear factor-kappaB (NF-kappaB) and the signaling pathways that regulate its activity have become a focal point for intense drug discovery and development efforts. NF-kappaB regulates the transcription of a large number of genes, particularly those involved in immune, inflammatory, and antiapoptotic responses. In our search for NF-kappaB inhibitors from natural resources, we identified cardamomin, 2’,4’-dihydroxy-6’-methoxychalcone, as an inhibitor of NF-kappaB activation from Alpinia conchigera Griff (Zingiberaceae). In present study, we demonstrated the effect of cardamomin on NF-kappaB activation in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and LPS-induced mortality. This compound significantly inhibited the induced expression of NF-kappaB reporter gene by LPS or tumor necrosis factor (TNF)-alpha in a dose-dependent manner. LPS-induced production of TNF-alpha and NO as well as expression of inducible nitric-oxide synthase and cyclooxygenase-2 was significantly suppressed by the treatment of cardamomin in RAW264.7 cells. Also, cardamomin inhibited not only LPS-induced degradation and phosphorylation of inhibitor kappaBalpha (IkappaBalpha) but also activation of inhibitor kappaB (IkappaB) kinases and nuclear translocation of NF-kappaB. Further analyses revealed that cardamomin did not directly inhibit IkappaB kinases, but it significantly suppressed LPS-induced activation of Akt. Moreover, cardamomin suppressed transcriptional activity and phosphorylation of Ser536 of RelA/p65 subunit of NF-kappaB. However, this compound did not inhibit LPS-induced activation of extracellular signal-regulated kinase and stress-activated protein kinase/c-Jun NH(2)-terminal kinase, but significantly impaired activation of p38 mitogen-activated protein kinase. We also demonstrated that pretreatment of cardamomin rescued C57BL/6 mice from LPS-induced mortality in conjunction with decreased serum level of TNF-alpha. Together, cardamomin could be valuable candidate for the intervention of NF-kappaB-dependent pathological condition such as inflammation.
J Pharmacol Exp Ther. 2006 Jan;316(1):271-8
Antinociceptive mechanisms of orally administered decursinol in the mouse.
Antinociceptive profiles of decursinol were examined in ICR mice. Decursinol administered orally (from 5 to 200 mg/kg) showed an antinociceptive effect in a dose-dependent manner as measured by the tail-flick and hot-plate tests. In addition, decursinol attenuated dose-dependently the writhing numbers in the acetic acid-induced writhing test. Moreover, the cumulative response time of nociceptive behaviors induced by an intraplantar formalin injection was reduced by decursinol treatment during the both 1st and 2nd phases in a dose-dependent manner. Furthermore, the cumulative nociceptive response time for intrathecal (i.t.) injection of TNF-alpha (100 pg), IL-1 beta (100 pg), IFN-gamma (100 pg), substance P (0.7 microg) or glutamate (20 microg) was dose-dependently diminished by decursinol. Intraperitoneal (i.p.) pretreatment with yohimbine, methysergide, cyproheptadine, ranitidine, or 3,7-dimethyl-1-propargylxanthine (DMPX) attenuated inhibition of the tail-flick response induced by decursinol. However, naloxone, thioperamide, or 1,3-dipropyl-8-(2-amino-4-chloro-phenyl)-xanthine (PACPX) did not affect inhibition of the tail-flick response induced by decursinol. Our results suggests that decursinol shows an antinociceptive property in various pain models. Furthermore, antinociception of decursinol may be mediated by noradrenergic, serotonergic, adenosine A(2), histamine H(1) and H(2) receptors.
Life Sci. 2003 Jun 13;73(4):471-85
The antioxidative and immunostimulating properties of d-glucosamine.
The objective of the present study was to investigate the antioxidant activity and immunostimulating property of glucosamine (GlcN) using various in vitro and in vivo tests. Results showed that GlcN possessed excellent antioxidant activities as manifested by strong chelating effect on ferrous ions and protection of macromolecules such as protein, lipid, and deoxyribose from oxidative damage induced by hydroxyl radicals. The immunostimulating effects of GlcN were further evaluated through various immunological tests. GlcN showed excellent activity of enhancing splenocyte proliferation. Neutral red pinocytosis and NO production in mouse peritoneal macrophages were significantly augmented. Oral administration of GlcN to mice for 20 days significantly enhanced the serum antibody level in mice in response to sheep red blood cells (SRBC), increased the relative organ weight of spleen and thymus tissue, and promoted the delayed-type hypersensitivity (DTH) against SRBC as compared with control group. In conclusion, the present investigation reveals GlcN is biologically functional in antioxidative activities and immunostimulating properties.
Int Immunopharmacol. 2007 Jan;7(1):29-35
Glucosamine long-term treatment and the progression of knee osteoarthritis: systematic review of randomized controlled trials.
OBJECTIVE: To investigate the structural and symptomatic efficacy and safety of glucosamine in knee osteoarthritis (OA). DATA SOURCES: Clinical trials of glucosamine were identified through electronic searches (MEDLINE, EMBASE, BIOSIS, EMB review, the Cochrane Library) using the key words glucosamine, osteoarthritis, degenerative joint disease, degenerative arthritis, osteoarthrosis, gonarthrosis, knee, disease progression, and clinical trial. The bibliographic databases were searched from their respective inception dates to August 2004. We also hand-searched reference lists of relevant articles. STUDY SELECTION AND DATA EXTRACTION: Studies were included if they were double-blind, randomized, controlled trials that evaluated oral glucosamine long-term treatment in knee OA; lasting at least one year; and reporting as outcome measures the symptom severity and disease progression as assessed by joint space narrowing. Two authors interpreted data independently. Disagreements were resolved through discussion. DATA SYNTHESIS: Glucosamine sulfate was more effective than placebo in delaying structural progression in knee OA. The risk of disease progression was reduced by 54% (pooled RR 0.46; 95% CI 0.28 to 0.73; p = 0.0011). The number-needed-to-treat was 9 (95% CI 6 to 20). The pooled effect sizes for pain reduction and improvement in physical function were 0.41 (95% CI 0.21 to 0.60; p < 0.0001) and 0.46 (95% CI 0.27 to 0.66; p < 0.0001), respectively, in favor of glucosamine sulfate. Glucosamine sulfate caused no more adverse effects than placebo. CONCLUSIONS: The available evidence suggests that glucosamine sulfate may be effective and safe in delaying the progression and improving the symptoms of knee OA. Due to the sparse data on structural efficacy and safety, further studies are warranted.
Ann Pharmacother. 2005 Jun;39(6):1080-7