Description: |
Medicarpin, a legume phytoalexin, acts as an estrogen receptor (ER) agonist, can stimulate osteoblast differentiation likely via ERβ, promote achievement of peak bone mass, and is devoid of uterine estrogenicity; in addition, given its excellent oral bioavailability, it can be potential osteogenic agent. Medicarpin sensitizes myeloid leukemia cells to TRAIL-induced apoptosis through the induction of DR5 and activation of the ROS-JNK-CHOP pathway. Medicarpin also has antifungal activity. |
In vitro: |
Environ Sci Pollut Res Int. 2014 Dec;21(24):14091-8. | Effect of lead treatment on medicarpin accumulation and on the gene expression of key enzymes involved in medicarpin biosynthesis in Medicago sativa L.[Pubmed: 25053287] | Lead (Pb) is the most common heavy metal contaminant in the environment. The present study was undertaken to determine the effect of Pb treatment on Medicarpin production and accumulation in Medicago sativa L.
METHODS AND RESULTS:
To this aim, 7- and 30-day-old plants were treated with 0, 120, 240, 500, and 1,000 μM Pb during 10 days. The content of Medicarpin was determined by HPLC, and the extent of Medicarpin production was deduced from the result of semiquantitative RT-PCR performed on PAL, CHS, and VR genes. HPLC results indicated that Medicarpin concentration has been reduced in the roots, while its exudation to the culture medium has been increased. RT-PCR results indicated that the transcript levels of PAL, CHS, and VR genes have not been affected following Pb stress in seedlings. At the vegetative stage, transcript levels of PAL and CHS genes have been reduced in the roots. However, the transcript level of VR gene increased at 120 and 240 μM Pb, while it decreased at higher concentrations. In the shoot, the transcript levels of PAL, CHS, and VR genes were increased following increased concentration of lead in the medium.
CONCLUSIONS:
Overall, q-PCR results suggest that Medicarpin biosynthesis has been induced in the shoots and reduced in the roots of the plants treated with a toxic concentration of Pb. | Pharmacology. 1985;31(5):289-93. | Specificity of medicarpin and related isoflavonoids in inhibition of rat hepatic mixed function oxidase activity.[Pubmed: 3877941] | The cytochromes P-450 of the mixed function oxidase system metabolize a wide variety of endogenous compounds to either nontoxic products or toxic metabolites. A number of natural products, such as flavonoids, influence this metabolism. Exposure to these compounds may therefore be a factor in animal and human responsiveness to cytochrome P-450 substrates.
METHODS AND RESULTS:
We have examined the effect of the pterocarpan Medicarpin on the cytochrome P-450-dependent aryl hydrocarbon hydroxylase (AHH) and ethoxycoumarin deethylase (ECD) activities of rat liver microsomes. Medicarpin and maackiain and two of their biosynthetic precursors inhibit the constitutive and phenobarbital (PB)-induced types of AHH, but have little effect on the 3-methylcholanthrene (MC)-induced type of AHH. This is in contrast to the effect of the commonly used cytochrome P-450 inhibitor 7,8-benzoflavone, which inhibits the hepatic AHH of MC-treated rats and has no effects on the AHH of control or PB-treated rats. However, Medicarpin inhibited the constitutive as well as the PB- and MC-induced ECD.
CONCLUSIONS:
The specific modulatory effect as well as its relative availability suggests the utility of Medicarpin as a probe for different forms of cytochrome P-450 in animal tissues. | Phytomedicine . 2015 Dec 1;22(13):1186-94. | Medicarpin and millepurpan, two flavonoids isolated from Medicago sativa, induce apoptosis and overcome multidrug resistance in leukemia P388 cells[Pubmed: 26598918] | Abstract
Background: High consumption of flavonoids has been associated with a decrease risk of cancer. Alfalfa (Medicago sativa) leaves have been widely used in traditional medicine and is currently used as a dietary supplement because of their high nutrient content. We previously reported the cytotoxic activity of alfalfa leaf extracts against several sensitive and multidrug resistant tumor cell lines.
Hypothesis/purpose: We aimed to determine whether Medicarpin and millepurpan, two isoflavonoids isolated from alfalfa leaves, may have pro-apoptotic effects against drug-sensitive (P388) and multidrug resistant P388 leukemia cells (P388/DOX).
Study design/methods: Cells were incubated with Medicarpin or millepurpan for the appropriate time. Cell viability was assessed by the MTT assay. DNA fragmentation was analyzed by agarose gel electrophoresis. Cell cycle analysis was realized by flow cytometry technics. Caspases 3 and 9 activities were measured using Promega caspACE assay kits. Proteins and genes expression were visualized respectively by western-blot using specific antibodies and RT-PCR assay.
Results: P-glycoprotein-expressing P388/DOX cells did not show resistance to Medicarpin (IC50 ≈ 90 μM for P388 and P388/DOX cells) and millepurpan (IC50 = 54 μM and 69 μM for P388 and P388/DOX cells, respectively). Treatment with Medicarpin or millepurpan triggered apoptosis in sensitive as well as multidrug resistant P388 cells. These effects were mediated through the mitochondrial pathway by modifying the balance pro/anti-apoptotic proteins. While 3 μM doxorubicin alone could not induce cell death in P388/DOX cells, concomitant treatment with doxorubicin and subtoxic concentration of Medicarpin or millepurpan restored the pro-apoptotic cascade. Each compound increased sensitivity of P388/DOX cells to doxorubicin whereas they had no effect in sensitive P388 cells. Vinblastine cytotoxicity was also enhanced in P388/DOX cells (IC50 = 210 nM to 23 and 25 nM with Medicarpin and millepurpan, respectively). This improved sensitivity was mediated by an increased uptake of doxorubicin in P388/DOX cells expressing P-gp. P-gp expression was not altered by exposure to Medicarpin and millepurpan.
Conclusion: These data indicate that Medicarpin and millepurpan possess pro-apoptotic properties and potentiate the cytotoxicity of chemotherapy drugs in multidrug resistant P388 leukemia cells by modulating P-gp-mediated efflux of drugs. These flavonoids may be used as chemopreventive agents or as sensitizer to enhance cytotoxicity of chemotherapy drugs in multidrug resistant cancer cells.
Keywords: Alfalfa; Apoptosis; Flavonoids; Medicarpin; Millepurpan; Multidrug resistance. |
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In vivo: |
Mol Cell Endocrinol. 2010 Aug 30;325(1-2):101-9. | Medicarpin inhibits osteoclastogenesis and has nonestrogenic bone conserving effect in ovariectomized mice.[Pubmed: 20570709] | Medicarpin, a pterocarpan class of naturally occurring benzopyran furanobenzene compound was synthesized in gram scale to investigate its effects on murine bone cells and in ovariectomized (OVx) mice.
METHODS AND RESULTS: 1
Medicarpin, at as low as 10(-10)M suppressed osteoclastogenesis in bone marrow cells (BMCs). Medicarpin-induced apoptosis of mature osteoclasts isolated from long bones. Effects of Medicarpin in osteoclasts appear to be independent of estrogen receptor (ER) activation as ICI 180,782 failed to abrogate its effects on osteoclasts. In calvarial osteoblasts, Medicarpin (10(-10)M) blocked nuclear factor kappaB (NF-kappaB) signaling assessed by tumor necrosis factor alpha (TNFalpha)-stimulated nuclear translocation of p65 subunit of NF-kappaB. Medicarpin also inhibited the expression of TNFalpha in mouse calvarial osteoblasts. This effect was ER dependent as ICI 180,782 reversed the suppressive effect of Medicarpin on TNFalpha mRNA levels in osteoblasts. In addition, like 17beta-estradiol, presence of Medicarpin inhibited TNFalpha-induced upregulation of interleukin-1, and -6 mRNA levels in osteoblasts. In co-cultures consisting of calvarial osteoblasts and BMCs, presence of Medicarpin increased osteoprotegerin (OPG)/receptor activator of NF-kappaB ligand (RANKL) ratio and reduced mRNA levels of osteoclast markers including tartrate-resistant acid phosphatase and RANK. OVx mice administered Medicarpin (10.0mgkg(-1)day(-1)) orally for 30days had reduced formation of osteoclasts but increased formation of osteoprogenitor cells in BMCs compared with OVx+vehicle group. Medicarpin treatment to OVx mice maintained parameters of trabecular microarchitecure. Medicarpin exhibited no uterine estrogenicity.
CONCLUSIONS:
Our findings point towards direct and indirect inhibitory effects of Medicarpin on osteoclastogenesis in vitro that contribute to its bone sparing effect in OVx mice. |
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