Chemical Properties
Grape seed extract has an astrigent taste.
Occurrence
Grapeseed is found throughout the world.
Uses
Grapeseed may be used as an antioxidant and an anticancer treatment. It may also be used to treat varicose veins, circulatory problems, and vision problems such as cataracts, and to improve vision by lessening eye strain.
Composition
Standardized grape seed extracts are reported to contain 74 to 78% oligomeric proanthocynidins and less than approx- imately 6% of free favanol monomers on a dry weight basis Specifcally, grape seed extract contains the favanol monomers (+)-cat- echin, (–)-epicatechin, (–)-epicatechin gallate, (–)-epigallocatechin and (–)-epigallocatechin gallate.
Anticancer Research
Grape seed extract (GSE) has high quantities of proanthocyanidins and resveratrol.Human colorectal cancer cell (CRC) exposure to GSE (Schonthal 2012) resulted inmodified ER chaperones glucose-related protein-78 (GRP78) and protein disulphideisomerase (PDI). GRP78 is needed for integrity of ER as well as stress-inducedautophagy (Flaumenhaft et al. 2015). PDI, a thiol-disulphide oxidoreductase,catalyses the disulphide bonds in newly synthesized proteins in the ER lumen (Hanet al. 2013; Wang and Kaufman 2014; Perri et al. 2016), and PDIA3 is localized tothe ER and is involved in protein folding (Wang et al. 2012b). Studies on the role ofPDI in cancer have demonstrated a pro-oncogenic, pro-survival role for PDI incancer and therapeutic resistance. PDI aids in ameliorating stress-induced apoptosisand causes degradation of wrongly folded proteins (Dinicola et al. 2010; Xu et al.2014). Hence, any obstruction caused in the activity of PDI will induce stress in thecell and lead to cell apoptosis. Fructose bisphosphate aldolase, a key enzymeinvolved in glycolysis, is also a potential target of GSE (Vandewynckel et al. 2016).The ER stress leads the cell to undergo apoptotic pathways in multiple ways andhence inhibits the proliferation of the targeted cells (Farooqi et al. 2015).
Safety
Grape seed extract is generally well tolerated when taken in moderate amounts. It has been tested safely for up to 11 months in human studies. It’s possibly unsafe if you have a bleeding disorder or are going to have surgery or if you take anticoagulants (blood thinners), such as warfarin or aspirin. Little is known about whether it’s safe to use grape seed extract during pregnancy or while breastfeeding.
