Pomegranate seed oil rich in conjugated linolenic acid suppresses chemically induced colon carcinogenesis in rats

Abstract

Pomegranate (Punica granatum L.) seed oil (PGO) contains more than 70% cis(c)9,trans(t)11,c13-18:3 as conjugated linolenic acids (CLN). Our previous short-term experiment demonstrated that seed oil from bitter melon (Momordica charantia) (BMO), which is rich in c9,t11,t13-CLN, inhibited the occurrence of colonic aberrant crypt foci (ACF) induced by azoxymethane (AOM). In this study, we investigated the effect of dietary PGO on the development of AOM-induced colonic malignancies and compared it with that of conjugated linoleic acid (CLA). To induce colonic tumors, 6-week old male F344 rats were given subcutaneous injections of AOM (20 mg/kg body weight) once a week for 2 weeks. One week before the AOM treatment they were started on diet containing 0.01%, 0.1%, or 1% PGO or 1% CLA for 32 weeks. Upon termination of the bioassay (32 weeks) colon tumors were evaluated histopathologically. AOM exposure produced colonic adenocarcinoma with an incidence of 81% and multiplicity of 1.88 ± ± ± ±1.54 at week 32. Administration of PGO in the diet significantly inhibited the incidence (AOM + + + +0.01% PGO, 44%, P < < < <0.05; AOM + + + +0.1% PGO, 38%, P < < < <0.01; AOM + + + +1% PGO, 56%) and the multiplicity (AOM + + + +0.01% PGO, 0.56 ± ± ± ±0.73, P < < < <0.01; AOM + + + +0.1% PGO, 0.50 ± ± ± ±0.73, P < < < <0.005; AOM + + + +1% PGO, 0.88 ± ± ± ±0.96, P < < < <0.05) of colonic adenocarcinomas, although a clear dose-response relationship was not observed at these dose levels. CLA feeding also slightly, but not significantly, reduced the incidence and multiplicity of colonic adenocarcinomas. The inhibition of colonic tumors by PGO was associated with an increased content of CLA (c9,t11-18:2) in the lipid fraction of colonic mucosa and liver. Also, administration of PGO in the diet elevated expression of peroxisome proliferator-activated receptor ( olon cancer is one of the leading causes of cancer deaths in Western countries. Globally, more than 875,000 men and women were afflicted with this cancer in 1996 and more than 510,000 died in the same year.

Fractionation and identification of 9c, 11t, 13t-conjugated linolenic acid as an activator of PPARα in bitter gourd (Momordica charantia L.)

“…Indeed, the juice or whole powder of bitter gourd fruit has been reported to have various medicinal properties, including anticarcinogenic [20], hypoglycemic [13,16,24,36], and hypotriglyceridemic [15] effects. These effects are closely related to the role of PPAR in regulating lipid and glucose homeostasis, cellular differentiation and apoptosis, and cancer development as well as in controlling the inflammatory response [17].…”

In vitro antiproliferative, apoptotic and antioxidant activities of punicalagin, ellagic acid and a total pomegranate tannin extract are enhanced in combination with other polyphenols as found in pomegranate juice

“…Pomegranate juice and extracts have been shown to have potent in vitro antioxidant [7,24] and in vivo anti-atherosclerotic properties [8,9,15], attributed to its high content of polyphenols including ETs and EA. Recently, there have also been numerous reports on the in vitro and in vivo anticancer properties of pomegranates [10,[25][26][27][28][29][30]. The major pomegranate ET, punicalagin, is reported as the active ingredient responsible for N 50% of the juice's antioxidative potential [7,24] and can reach levels of N2 g/L of juice [7].…”

Pomegranate (Punica granatum): a natural source for the development of therapeutic compositions of food supplements with anticancer activities based on electron acceptor molecular characteristics

“…Several laboratory and clinical studies have demonstrated the anti-inflammatory, antiatherosclerotic, anti-cancer, and anti-viral activities of pomegranate juice [3][4][5][6][7][8][9][10][11][12][13][59][60][61][62][63][64][65][66]. However, these studies still leave the question of whether these extraordinary health effects of pomegranate are the consequence of some unique properties of the pomegranate ingredients open to discussion.…”

“…For this reason, increased attention has turned to complementary therapies, including natural dietary supplements. Among these natural agents, pomegranate (Punica granatum) juice has drawn a great deal of attention from both the scientific community and the general public due to its demonstrated ability to suppress cancers [3][4][5][6][7][8][9][10][11][12][13]. For example, pomegranate has been found to possess well-documented cancer chemopreventive and chemotherapeutic effects against prostate cancer [10][11][12][13].…”