This is prompted by a new paper [4c].
The muscadine is not my least favorite grape - at least while the concord is around - but I'm not about to look for a source. On the other hand:
"Muscadine grapes are rich sources of polyphenols and other nutrients studied for their potential health benefits. Gallic acid, (+)-catechin and epicatechin are the major phenolics in seeds, while ellagic acid, myricetin, quercetin, kaempferol, and trans-resveratrol are the major phenolics in the skins." [1]
There are two distinct products on the market - derived from the seeds & the skins.
"The rank order of total phenolic content among muscadine components was found to be seeds >> skins > leaves >> pulp." [1]
[2] (2007 - U.S.)
"Inhibition of prostate cancer growth by muscadine grape skin extract and resveratrol through distinct mechanisms."
"We compared the antitumor activities of muscadine grape skin extract (MSKE), which we show contains no resveratrol, with that of resveratrol using primary cultures of normal prostate epithelial cells (PrEC) and the prostate cancer cell lines RWPE-1, WPE1-NA22, WPE1-NB14, and WPE1-NB26, representing different stages of prostate cancer progression. MSKE significantly inhibited tumor cell growth in all transformed prostate cancer cell lines but not PrEC cells. Prostate tumor cell lines, but not PrEC cells, exhibited high rates of apoptosis in response to MSKE through targeting of the phosphatidylinositol 3-kinase–Akt and mitogen-activated protein kinase survival pathways."
[3] (2015 - Johns Hopkins) Denmeade, whose name came up recently in the context of BAT, was part of the team.
"In the phase I portion of this phase I/II study non-metastatic BRPC patients were assigned to increasing doses of MPX (Muscadine Naturals Inc., Clemmons, NC) in cohorts of 2 patients, with 6 patients at the highest dose ..."
"Initial dose selection was based on preclinical data showing the equivalent of 500 to 4,000 mg of MPX to be safe in mouse models."
"Seven patients remain on study. The lack of dose limiting toxicities led to the selection of 4000 mg/d as the highest dose for further study. Median within-patient PSADT increased by 5.3 months ..."
[4] Liza J Burton / Valerie A Odero-Marah, et al, are responsible for 3 of the 5 papers. (2014/2015/2016 - U.S.)
[4a] "Muscadine grape skin extract reverts snail-mediated epithelial mesenchymal transition via superoxide species in human prostate cancer cells"
{"epithelial-mesenchymal transition" pertains to morphological changes that occur in PCa cells as part of the the metastasis process.}
"Snail transcription factor can induce epithelial-mesenchymal transition (EMT), associated with decreased cell adhesion-associated molecules like E-cadherin, increased mesenchymal markers like vimentin, leading to increased motility, invasion and metastasis. Muscadine grape skin extract (MSKE) has been shown to inhibit prostate cancer cell growth and induce apoptosis without affecting normal prostate epithelial cells. We investigated novel molecular mechanisms by which Snail promotes EMT in prostate cancer cells via Reactive Oxygen Species (ROS) and whether it can be antagonized by MSKE."
"Collectively, our results indicate that Snail leads to increased levels of mitochondrial superoxide and EMT (Figure 6). Furthermore, MSKE and SOD reverts EMT by targeting Snail expression (Figure 6), underscoring the importance of targeting these pathways with various inhibitors and antioxidants. These studies show that superoxide species may play a role in the EMT process and that use of various antioxidants such as MSKE may be able to antagonize EMT and prostate cancer progression in future."
[4b] "Muscadine grape skin extract can antagonize Snail-cathepsin L-mediated invasion, migration and osteoclastogenesis in prostate and breast cancer cells"
"The aim of this report is to show that MSKE, a natural product, can antagonize Snail-mediated signaling and bone turnover.
[4c] "Muscadine Grape Skin Extract Induces an Unfolded Protein Response-Mediated Autophagy in Prostate Cancer Cells: A TMT-Based Quantitative Proteomic Analysis"
{autophagy is an alternative form of cell death to the popular apoptosis}
-Patrick
[1] en.wikipedia.org/wiki/Vitis...
[2] cancerres.aacrjournals.org/...
[3] ncbi.nlm.nih.gov/pmc/articl...
[4a] ncbi.nlm.nih.gov/pmc/articl...
"Superoxide dismutase (SOD) can be considered as a therapy for late-stage prostate cancer" only an in vitro study I'm afraid
