Myricetin Protects Cells against Oxidative Stress-Induced Apoptosis via Regulation of PI3K/Akt and MAPK Signaling Pathways

Abstract

Recently, we demonstrated that myricetin exhibits cytoprotective effects against H2O2-induced cell damage via its antioxidant properties. In the present study, myricetin was found to inhibit H2O2-induced apoptosis in Chinese hamster lung fibroblast (V79-4) cells, as shown by decreased apoptotic bodies, nuclear fragmentation, sub-G1 cell population, and disruption of mitochondrial membrane potential (Δψm), which are increased in H2O2-treated cells. Western blot data showed that in H2O2-treated cells, myricetin increased the level of Bcl-2, which is an anti-apoptotic factor, and decreased the levels of Bax, active caspase-9 and -3, which are pro-apoptotic factors. And myricetin inhibited release of cytochrome c from mitochondria to cytosol in H2O2-treated cells. Myricetin-induced survival correlated with Akt activity, and the rescue of cells by myricetin treatment against H2O2-induced apoptosis was inhibited by the specific PI3K (phosphoinositol-3-kinase) inhibitor. Myricetin-mediated survival also inhibited the activation of p38 mitogen activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK), which are members of MAPK. Our studies suggest that myricetin prevents oxidative stress-induced apoptosis via regulation of PI3K/Akt and MAPK signaling pathways.

Continuous Blood Purification Ameliorates Multiple Organ Failure Through Inhibiting the Activation of the P38 MAPK Signaling Pathway in a Rat Model

“…p38 MAPK signaling pathway was a prominent factor on regulating cell apoptosis, immune, and inflammatory responses through its positive regulation on the posttranscriptional control of TNF-α and the cytokine expression under stress conditions, including I/R injury [28][29][30]. I/R injury is a common pathological condition that could cause acute inflammatory reaction, severe MOF, and even mortality [31].…”

Natural fruit extracts as non-toxic fluorescent dyes for staining fungal chlamydospores

“…There is increasing evidence that protective pharmacological substances such as anthocyanins, cumarin, myricetin, quinones, tannins, carotenoids, and flavonols from fruit of higher plants absorb incident light at specific wavelengths, offering a spectral range for fluorescence excitation (Kang et al 2010;Merzlyak et al 2008;Yip et al 1993;Rost 1995). Although the screening of natural plant extracts has shown that plant fruits bear a great potential for new fluorescent compounds or fluorophores (Buschmann et al 2000;Goodwin 1953), little attention has been paid to these inexpensive natural products in microbiology, including mycology.…”

“…One such stain is lactofuchsin (Carmichael 1955), used as a mounting medium and staining agent for studying fungi. Although the lactofuchsin mixture binds well to the cell walls of fungi, its toxicity negatively impacts certain Zygomycota, Ascomycota, and Basidiomycota strains (Bragulat et al 1991;Chau et al 2010).…”

“…Since Stokes discovered the applicability of fluorescence staining in 1853, microscopic imaging has rapidly evolved (Valeur 2002;Harris 2005) to use a wide array of natural and synthetic dyes or probes in different biological and medical fields (Lillie 1977;Rietdorf 2005;Valeur 2002). Calcofluor, trypan blue, chlorazole black E, lactofuchsin, fluorescein isothiocyanate (FITC), 4,6-diamidino 2-phenylindole (DAPI), green fluorescent protein (GFP), Hoechst 33258 (bisbenzimide), Nile red, and Brilliant blue FCF are some common fluorescent stains (Chau et al 2010), dyes, or probes employed for fluorescence, epifluorescence, and confocal microscopy to study fungi and other microbes (Harris 2005;Hoch et al 2005;Kangatharalingam and Ferguson 1984;Lorang et al 2001;Lillie 1977). Like other organisms, most fungal cells have low optical visibility under the conventional light microscope.…”

Myricetin inhibits Kv1.5 channels in HEK293 cells

“…1A. Myr has a variety of pharmacological effects, including anti-bacterial (8), analgesic (8), anti-tumor (9,10), anti-allergic (11)(12)(13), anti-oxidant (14,15), blood sugar-lowering (16) and hepatoprotective actions (17). It also exerts protective effects against cardiovascular diseases, including atherosclerosis (18), ischemia-reperfusion injury (19), myocardial infarction (20) and hypertension (21,22).…”