Structural determinants of plant lignans for growth of mammary tumors and hormonal responses in vivo

Saarinen, Niina M.; Penttinen, P.E.; Smeds, Annika; Hurmerinta, Teija T.; Mäkelä, Sari

doi:10.1016/j.jsbmb.2004.12.004

Cited by 29 publications

(20 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Oral administration of enterolactone inhibited the mammary carcinomas in the same rat model (Saarinen et al 2001(Saarinen et al , 2002a. According to Saarinen et al (2005) this difference in the biological response in vivo can be explained by the effect of the plant lignan structure (a hydroxyl group position) on the metabolite profile in the rat (Saarinen et al 2005). Thus the structural diversity of lignans and their metabolites makes identification of biologically active components even more complex.…”

Section: Significance Of Phenolic Metabolites For Human Healthmentioning

confidence: 99%

Microbial metabolism of dietary phenolic compounds in the colon

2008

View full text Add to dashboard Cite

Plant foods contain substantial amounts of phenolic compounds. Dietary interventions with phenolic supplementation show that phenolic compounds are transformed into phenolic acids or lactone structures by intestinal microbiota. The colon is the main site of microbial fermentation. The metabolites circulate in plasma and are excreted via urine. The entero-hepatic circulation ensures that their residence time in plasma is extended compared to that of their parent compounds. Thus these metabolites may exert systemic effects, which however have not been studied adequately. In particular the health implications of microbial metabolites of flavonoids, mostly phenolic acids, are unknown. This review aims to elucidate the microbial metabolism of most of the phenolic classes: flavonoids, isoflavonoids, lignans, phenolic acids and tannins. Some examples of biological activity studies of flavonoid and lignan metabolites are given. Biological significance of enterolactone, a mammalian plant lignan metabolite, has been studied quite extensively, but convincing evidence of the health benefits of the diverse pool of microbial metabolites is still scarce. Hopefully, novel tools in systems biology and the constant search for biomarkers will elucidate the role of the phenolic metabolome in health and in the prevention of chronic diseases. In conclusion, the colon is not only an excretion route, but also an active site of metabolism and deserves further attention from the scientific community.

show abstract

Section: Significance Of Phenolic Metabolites For Human Healthmentioning

confidence: 99%

Microbial metabolism of dietary phenolic compounds in the colon

2008

View full text Add to dashboard Cite

show abstract

“…In reviewing the evidence of genistein on breast cancer growth in vivo, De Lemos (2001) concluded that this phytoestrogen stimulated growth at low concentrations, but at high concentrations inhibited tumor growth. Few in vivo studies have been carried out on other phytoestrogens although anti-tumor effects of apigenin, quercetin, and enterolactone have been reported (Caltagirone et al 2000, Chen et al 2004, Saarinen et al 2005.…”

Section: In Vivo Studiesmentioning

confidence: 99%

Phytoestrogens and breast cancer –promoters or protectors?

Rice¹,

Whitehead²

2006

Endocr Relat Cancer

164

119

View full text Add to dashboard Cite

The majority of breast cancers are oestrogen dependent and in postmenopausal women the supply of oestrogens in breast tissue is derived from the peripheral conversion of circulating androgens. There is, however, a paradox concerning the epidemiology of breast cancer and the dietary intake of phytoestrogens that bind weakly to oestrogen receptors and initiate oestrogendependent transcription. In Eastern countries, such as Japan, the incidence of breast cancer is approximately one-third that of Western countries whilst their high dietary intake of phytoestrogens, mainly in the form of soy products, can produce circulating levels of phytoestrogens that are known experimentally to have oestrogenic effects. Indeed, their weak oestrogenicity has been used to advantage by herbalist medicine to promote soy products as a natural alternative to conventional hormone replacement therapy (HRT). Such usage could increase in light of recent evidence that long-term HRT usage may be associated with an increased risk of breast cancer with a consequent reduction in prescription rates. So, are phytoestrogens safe as a natural alternative to HRT and could they be promoters or protectors of breast cancer? If they are promoters, then we must assume that it is due to their oestrogenic effect. If they are protectors, then other actions of phytoestrogens, including their ability to inhibit enzymes that are responsible for converting androgens and weak oestrogens into oestradiol, must be considered. This paper addresses these questions by reviewing the actions of phytoestrogens on oestrogen receptors and key enzymes that convert androgens to oestrogens in relation to the growth of breast cancer cells. In addition, it compares the experimental and epidemiological evidence pertinent to the potential beneficial or harmful effects of phytoestrogens in relation to the incidence/progression of breast cancer and their efficacy as natural alternatives to conventional HRT.

show abstract

“…Lignans have also been investigated for their effects on cell growth. At low doses enterolactone stimulated but at concentrations above 10 µM, it inhibited proliferation of MCF7 cells [24,25].…”

Section: Introductionmentioning

confidence: 98%

Reference Profile Correlation Reveals Estrogen-like Trancriptional Activity of Curcumin

Bachmeier

Mirisola²,

Romeo³

et al. 2010

Cell Physiol Biochem

View full text Add to dashboard Cite

Background: Several secondary metabolites from herbal nutrient products act as weak estrogens (phytoestrogens), competing with endogenous estrogen for binding to the estrogen receptors and inhibiting steroid converting enzymes. However, it is still unclear whether these compounds elicit estrogen dependent transcription of genes at physiological concentrations. Methods: We compare the effects of physiological concentrations (100 nM) of the two phytoestrogens Enterolactone and Quercetin and the suspected phytoestrogen Curcumin on gene expression in the breast cancer cell line MCF7 with the effects elicited by 17-β-estradiol (E2). Results: All three phytocompounds have weak effects on gene transcription; most of the E2 genes respond to the phytoestrogens in the same direction though to a much lesser extent and in the order Curcumin > Quercetin > Enterolactone. Gene regulation induced by these compounds was low for genes strongly induced by E2 and similar to the latter for genes only weakly regulated by the classic estrogen. Of interest with regard to the treatment of menopausal symptoms, the survival factor Birc5/survivin and the oncogene MYBL1 are strongly induced by E2 but only marginally by phytoestrogens. Conclusion: This approach demonstrates estrogenic effects of putative phytoestrogens at physiological concentrations and shows, for the first time, estrogenic effects of Curcumin.

show abstract

Structural determinants of plant lignans for growth of mammary tumors and hormonal responses in vivo

Cited by 29 publications

References 56 publications

Microbial metabolism of dietary phenolic compounds in the colon

Microbial metabolism of dietary phenolic compounds in the colon

Phytoestrogens and breast cancer –promoters or protectors?

Reference Profile Correlation Reveals Estrogen-like Trancriptional Activity of Curcumin

Contact Info

Product

Resources

About