Myricetin is one of the flavonols.

Myricetin benefit
Myricetin may have anti-inflammatory activity. In test tube studies, myricetin has shown anti-tumor and antioxidant properties. Myricetin may also inhibit beta-amyloid fibril formation, a key problem with Alzheimer's disease. Flavonoids, including myrecetin, have antibacterial and antiviral activity.

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Myricetin research Update
Myricetin as the active principle of Abelmoschus moschatus to lower plasma glucose in streptozotocin-induced diabetic rats.
Planta Med. 2005 Jul;71(7):617-21. Department of Pharmacy, Tajen Institute of Technology, Yen-Pou, Ping Tung Shien, Taiwan, R.O.C.
The antihyperglycemic action of myricetin, purified from the aerial part of Abelmoschus moschatus (Malvaceae), was investigated in streptozotocin-induced diabetic rats. These results suggest that myricetin has an ability to enhance glucose utilization to lower plasma glucose in diabetic rats lacking insulin.

Dietary flavonoids as proteasome inhibitors and apoptosis inducers in human leukemia cells.
Biochem Pharmacol. 2005 May 15;69(10):1421-32.
Chen D, Daniel KG, Chen MS, Kuhn DJ, Landis-Piwowar KR, Dou QP.
The Prevention Program, Barbara Ann Karmanos Cancer Institute, and Department of Pathology, School of Medicine, Wayne State University, 640 HWCRC, 4100 John R, Detroit, MI
It has been shown that proteasome activity is required for cancer cell survival and consumption of fruits and vegetables is associated with decreased cancer risk. Previously, we reported that grape extract could inhibit proteasome activity and induce apoptosis in tumor cells. In this study, we examined the flavonoids apigenin, quercetin, kaempferol and myricetin for their proteasome-inhibitory and apoptosis-inducing abilities in human tumor cells. We report that apigenin and quercetin are much more potent than kaempferol and myricetin at: (i) inhibiting chymotrypsin-like activity of purified 20S proteasome and of 26S proteasome in intact leukemia Jurkat T cells; (ii) accumulating putative ubiquitinated forms of two proteasome target proteins, Bax and Inhibitor of nuclear factor kappabeta-alpha in Jurkat T cells and (iii) inducing activation of caspase-3 and cleavage of poly(ADP-ribose) polymerase in Jurkat T cells. The proteasome-inhibitory abilities of these compounds correlated with their apoptosis-inducing potencies. Results from computational modeling of the potential interactions of these flavonoids to the chymotrypsin site (beta5 subunit) of the proteasome were consistent with the obtained proteasome-inhibitory activities. We found that the C(4) carbon may be a site of nucleophilic attack by the OH group of N-terminal threonine of proteasomal beta5 subunit and that the C(3) hydroxyl may alter the ability of these flavonoids to inhibit the proteasome. Finally, apigenin neither effectively inhibited the proteasome activity nor induced apoptosis in non-transformed human natural killer cells. Our results suggested that the proteasome may be a target of these dietary flavonoids in human tumor cells and that inhibition of the proteasome by flavonoids may be one of the mechanisms responsible for their cancer-preventive effects.

Inhibition of interleukin-12 production in mouse macrophages via decreased nuclear factor-kappaB DNA binding activity by myricetin, a naturally occurring flavonoid.
Arch Pharm Res. 2005 Mar;28(3):274-9.
Pharmacological inhibition of interleukin-12 (IL-12) production may be a therapeutic strategy for preventing the development and progression of disease in experimental models of autoimmunity. In this study, the effects of myricetin, a naturally occurring flavonoid present in fruits, vegetables and medicinal herbs, on the production of IL-12 were investigated in mouse macrophages stimulated with lipopolysaccharide (LPS). Myricetin significantly inhibited the LPS-induced IL-12 production from both primary macrophages and the RAW264.7 monocytic cell-line in a dose-dependent manner. The effect of myricetin on IL-12 gene promoter activation was analyzed by transfecting RAW264.7 cells with IL-12 gene promoter/luciferase constructs. Furthermore, activation of macrophages by LPS resulted in markedly enhanced binding activity to the NF-kappaB site, which significantly decreased upon addition of myricetin, indicating that myricetin inhibited IL-12 production in LPS-activated macrophages via the down-regulation of NF-kappaB binding activity.

Preformed beta-amyloid fibrils are destabilized by coenzyme Q10 in vitro.
Biochem Biophys Res Commun. 2005 Apr 29;330(1):111-6.
Inhibition of the formation of beta-amyloid fibrils (fAbeta), as well as the destabilization of preformed fAbeta in the CNS, would be attractive therapeutic targets for the treatment of Alzheimer's disease. We reported previously that nordihydroguaiaretic acid (NDGA) and wine-related polyphenol, myricetin, inhibit fAbeta formation from Abeta and destabilize preformed fAbeta in vitro. Using fluorescence spectroscopic analysis with thioflavin T and electron microscopic studies, we examined the effects of coenzyme Q10 (CoQ(10)) on the formation, extension, and destabilization of fAbeta at pH 7.5 at 37 degrees C in vitro. We next compared the anti-amyloidogenic activities of CoQ10 with NDGA and myricetin. Coenzyme Q10 dose-dependently inhibited fAbeta formation from amyloid beta-peptide (Abeta), as well as their extension. Moreover, it destabilized preformed fAbetas. The anti-amyloidogenic effects of Coenzyme Q10 were slightly weaker than those of NDGA and myricetin. Coenzyme Q10 could be a key molecule for the development of therapeutics for Alzheimer's disease.

Anthocyanins, flavonols, and free radical scavenging activity of Chinese bayberry (Myrica rubra) extracts and their color properties and stability.
J Agric Food Chem. 2005 Mar 23;53(6):2327-32.
Characterization of anthocyanins and flavonols and radical scavenging activity assays of extracts from four Chinese bayberry (Myrica rubra) varieties with different fruit colors were carried out. One dominant anthocyanin and three major flavonols were isolated by HPLC, and cyanidin-3-O-glucoside and two of three flavonols, myricetin and quercetin-3-O-rutinoside, were identified by cochromatography with authentic standards. Both DPPH* and ABTS*(+) cation assays indicated that the black varieties (Biji and Hunan) demonstrated much higher radical scavenging activities than the pink (Fenhong) and yellow (Shuijing) varieties, which may be attributed to much higher levels of anthocyanins, flavonoids, and total phenolics in the black varieties.

Myricetin inhibits matrix metalloproteinase 2 protein expression and enzyme activity in colorectal carcinoma cells.
Mol Cancer Ther. 2005 Feb;4(2):281-90.
Colorectal carcinoma is a leading cause of human mortality due to its high metastatic ability. Because the activation of matrix metalloproteinases (MMP) is a key factor in the metastatic process, agents with the ability to inhibit MMP activity have potential in the treatment of colorectal carcinoma. In the present study, among 36 flavonoids examined, myricetin was found to be the most potent inhibitor of MMP-2 enzyme activity in COLO 205 cells. Myricetin inhibition of MMP-2 enzyme activity was also found in the human colorectal carcinoma cell lines COLO 320HSR, COLO 320DM, HT 29, and COLO 205-X (IC50 = 11.18, 11.56, 13.25, and 23.51 micromol/L, respectively). In contrast, no inhibitory effect of MMP-2 protein expression or enzyme activity was observed in myricitrin (myricetin-3-rhamnoside)-treated cells. Results of the present study indicate that myricetin significantly blocked both endogenous and TPA-induced MMP-2 enzyme activity by inhibiting its protein expression and enzyme activity. The blockade involved suppression of PKC translocation, ERK phosphorylation, and c-Jun protein expression. ahcc link Passionrx.net link resveratrol supplement link tribulusterrestrisextract.com link yohimbebark.net link tongkatali.net link ulinks and cruise.

Cactus Botanics introduces Myricetin extracted from Bayberry Bark
Myricetin is a flavonoid that is commonly found in natural food sources such as berries, vegetables, teas, wine and herbs. Myricetin is considered to be an antioxidant, which means that it is capable of eliminating free radicals within the body. It is usually taken from the bark, leaves, and roots of the plant known as myrica cerifera, and is completely water soluble, which means it makes an excellent source for teas. Cactus Botanics introduces Myricetin 80%, tested by HPLC.