Determination of some structural features of procyanidins and related compounds by photodiode-array detection

Bartolomé, Begoña; Hernández, Teresa; Bengoechea, Miguel; Quesada, C.; Gómez‐Cordovés, Carmen; Estrella, Isabel

doi:10.1016/0021-9673(95)00839-x

Cited by 60 publications

(41 citation statements)

References 22 publications

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“…Among these, flavonoids and isoflavones are receiving increased attention in recent years (Dragsted, 1998;Agarwal et al, 2000). Grape seed extract (GSE) is one such naturally occurring class of chemicals that is rich in procyanidins; a diverse group of flavonoid compounds also present in several fruits and vegetables (EscribanoBailon et al, 1992;Bartolome et al, 1996). Wine may also be a rich source of procyanidins (Halpern et al, 1998), and consumption of, particularly, red wine is shown to impart greater benefits in the prevention of coronary heart disease than other alcoholic beverages (Sato et al, 2001).…”

Section: Introductionmentioning

confidence: 99%

Grape seed extract inhibits EGF-induced and constitutively active mitogenic signaling but activates JNK in human prostate carcinoma DU145 cells: possible role in antiproliferation and apoptosis

2003

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A loss of functional androgen receptor and an enhanced expression of growth factor receptors and associated ligands are causal genetic events in prostate cancer (PCA) progression. These genetic alterations lead to an epigenetic mechanism where a feedback autocrine loop between membrane receptor and ligand (e.g. EGFR-TGFa) results in a constitutive activation of MAPK-Elk1-AP1-mediated mitogenic signaling in human PCA at an advanced and androgen-independent stage. We rationalized that inhibiting these epigenetic events could be useful in controlling advanced PCA growth. Recently, we found that grape seed extract (GSE), a dietary supplement rich in flavonoid procyanidins, inhibits advanced and androgenindependent human PCA DU145 cell growth in culture and nude mice. Here, we performed detailed mechanistic studies to define the effect of GSE on EGFR-Shc-MAPK-Elk1-AP1-mediated mitogenic signaling in DU145 cells. Pretreatment of serum-starved cells with GSE resulted in 70% to almost complete inhibition of EGF-induced EGFR activation and 50% to complete inhibition of Shc activation, which corroborated with a comparable decrease in EGF-induced Shc binding to EGFR. Conversely, EGF-induced ERK1/2 phosphorylation was inhibited only by lower doses of GSE; in fact, higher doses showed an increase. Additional studies showed that GSE alone causes a dose-and time-dependent increase in ERK1/2 phosphorylation in starved DU145 cells that is inhibited by an MEK1 inhibitor PD98059. Independent of this increase in ERK1/2 phosphorylation, GSE showed a strong inhibition of ERK1/2 kinase activity to Elk1 in both cellular and cell-free systems. GSE treatment of cells also inhibited both EGF-induced and constitutively active Elk1 phosphorylation and AP1 activation. GSE treatment also showed DNA synthesis inhibition in starved and EGF-stimulated cells as well as loss of cell viability and apoptotic death that was further increased by adding MEK1 inhibitor. Since GSE strongly induced apoptosis independent of its affect on an increase in phospho-ERK1/2, we hypothesized that apoptotic effect of GSE could be by other mechanism(s) including its effect on stress-associated MAPK, the JNK. Indeed, GSEtreated cells showed a strong and sustained increase in phospho-JNK1/JNK2 levels, JNK activity and phosphocJun levels. An inhibition of GSE-induced JNK activation by a novel JNK inhibitor SP600125 resulted in a significant reversal of GSE-induced apoptotic death suggesting the involvement of JNK activation by GSE in its apoptosis response. Together, these results suggest that anticancer effects of GSE in PCA be mediated via impairment of EGFR-ERK1/2-Elk1-AP1-mediated mitogenic signaling and activation of JNK causing growth inhibition and apoptosis, respectively.

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Section: Introductionmentioning

confidence: 99%

Grape seed extract inhibits EGF-induced and constitutively active mitogenic signaling but activates JNK in human prostate carcinoma DU145 cells: possible role in antiproliferation and apoptosis

2003

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“…Its active constituents are the proanthocyanidins, which represent a variety of polymers of flavan-3-ol such as catechin and epicatechin. [1][2][3][4] GSP is an antioxidant that is more powerful than catechins in aqueous system in vitro. [5][6][7] GSP has various physiological effects in vivo, such as antioxidant effects, 8,9) protection against X-ray and ultraviolet rays, 10,11) chemoprevention, 12,13) anti-cancer or anti-tumor effects, [14][15][16] and inhibitory effects against atherosclerosis and hypercholesterolemia.…”

Section: Introductionmentioning

confidence: 99%

Effects of Grape Seed Polyphenols on Serum and Hepatic Lipid Contents and Fecal Steroid Excretion in Normal and Hypercholesterolemic Rats.

Nakamura¹,

Tonogai²

2002

JOURNAL OF HEALTH SCIENCE

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The effects of grape seed polyphenol (GSP) administered orally at doses of 0.01-1.0 g/kg per day to normal and hypercholesterolemic rats for 28 and 36 days, respectively, was evaluated by measuring changes both in the concentrations of serum and hepatic lipids and in fecal steroid excretion. Body weight gain decreased dose-dependently both in normal and hypercholesterolemic rats. Relative weight of the liver was significantly lower in normal rats given more than 0.2 g/kg GSP compared with control rats. Compared with control groups, relative weight of the liver was significantly lower in normal rats given more than 0.2 g/kg GSP, and in hypercholesterolemic rats given more than 0.1 g/kg GSP, respectively. In hypercholesterolemic rats, food or calorie intake was significantly lower in rats given more than 0.1 g/kg GSP than in control rats. Dose-dependency was observed in serum concentrations of serum triglycerides and thiobarbituric acid reactive substances and the content of hepatic phospholipids in normal rats, and in serum concentration and hepatic content of triglycerides in hypercholesterolemic rats. A significant increase in fecal excretions of neutral steroids and bile acids was found in normal rats given a dose of 1.0 g/kg GSP. Dose-dependent decrease of 12-keto lithocholic acid and increase of lithocholic acid were also observed. By contrast, there was no significant change in fecal excretions of neutral steroids and bile acids in hypercholesterolemic rats. Thus, GSP seems to affect lipid metabolism in rats by lowering the concentrations of serum and hepatic triglycerides rather than by altering the metabolism of cholesterol.

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“…These values show that Banazi Black grape has a rich phenolic substance source in harmony with our study. Bartolomeo (1996) and Zhao (1999) reported that the fundamental phenolic content of the grape consisted of resveratrol, catechin ve epicatechin. In addition, the studies showed that grape was a rich phenolic compound source and 46-69% of these phenolic compounds was in the seed, 12-50% was in the skin, 8% or less was in the pulp.…”

Section: Discussionmentioning

confidence: 99%

The Effect of Different American Vine Rootstocks on the Phytochemical Characteristics in Dried Banazi Black Grape (Vitis Vinifera L.)

Çakir¹

2017

Appl. Ecol. Env. Res.

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Abstract.Banazi Black grape which is almost never consumed freshly is a very important, seed bearing, local type which is directly dried in the sun with its cluster without any processing. Ungrafted (5 years old and over 40 years old) and grafted (41B, 99R, 1103P and 110R) Banazi Black grape varieties which were 5 years old were used in the study conducted in Turkey, Malatya, Yesilyurt district, Konak town. The grapevines in the farmer vineyards, grown in dry conditions, were established in the form of blocks, serpene cultivation was applied on the stocks, and cane training was made. The photochemical characteristics of the dried grape belonging to the rootstocks used in 5 year-old Banazi Black grape which were ungrafted (5 and 40 years old ungrafted) and grafted with 41B, 99R, 1103P, 110R rootstocks were investigated in this study. It was determined from the analyzed phenolic compounds that gallic acid was 4.10-14.43 mg/kg; catechin was 146.87-306.87 mg/kg, rutin was 38.96-78.15 mg/kg, naringin was 22.54-50.97 mg/kg, phloridzin was 40.03-107.72 mg/kg, and quercetin was 0.47-1.67 mg/kg. Total antioxidant capacity in total phenolic substance rootstocks was determined to be 0.19-0.22 mg trolox equivalent/g; gallic acid/g was 7.51-21.66 mg. The amount of resveratrol was between 0.19-1.30 mg/kg among the rootstocks. The differences between the rootstocks were statistically significant in terms of phenolic compounds. 40 year-old ungrafted vinestock took a higher value when compared to the other rootstocks in terms of phenolic compounds.

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Determination of some structural features of procyanidins and related compounds by photodiode-array detection

Cited by 60 publications

References 22 publications

Grape seed extract inhibits EGF-induced and constitutively active mitogenic signaling but activates JNK in human prostate carcinoma DU145 cells: possible role in antiproliferation and apoptosis

Grape seed extract inhibits EGF-induced and constitutively active mitogenic signaling but activates JNK in human prostate carcinoma DU145 cells: possible role in antiproliferation and apoptosis

Effects of Grape Seed Polyphenols on Serum and Hepatic Lipid Contents and Fecal Steroid Excretion in Normal and Hypercholesterolemic Rats.

The Effect of Different American Vine Rootstocks on the Phytochemical Characteristics in Dried Banazi Black Grape (Vitis Vinifera L.)

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