Phytoestrogens

Collectively, plants contain several different families of natural products among which are compounds with weak estrogenic or antiestrogenic activity toward mammals. These compounds, termed phytoestrogens, include certain isoflavonoids, flavonoids, stilbenes, and lignans. The best-studied dietary phytoestrogens are the soy isoflavones and the flaxseed lignans. Their perceived health beneficial properties extend beyond hormone-dependent breast and prostate cancers and osteoporosis to include cognitive function, cardiovascular disease, immunity and inflammation, and reproduction and fertility. In the future, metabolic engineering of plants could generate novel and exquisitely controlled dietary sources with which to better assess the potential health beneficial effects of phytoestrogens

Isoflavone metabolism in domestic cats (Felis catus): comparison of plasma metabolites detected after ingestion of two different dietary forms of genistein and daidzein

Some felid diets contain isoflavones but the metabolic capacity of cats toward isoflavones is relatively unknown, despite the understanding that isoflavones have divergent biological potential according to their metabolite end products. The objective of this study was to determine the plasma metabolites detectable in domestic cats after exposure to 2 different dietary forms of isoflavones, either as a soy extract tablet ( n = 6) or as part of a dietary matrix ( n = 4). Serial blood samples were collected after isoflavone exposure to identify the plasma metabolites of each cat. Genistein was detected in its unconjugated form or as a monosulfate. Daidzein was detected as both a mono- and disulfate as well as in its unconjugated form. Other daidzein metabolites detected included equol mono- and disulfate, dihydrodaidzein, and O -desmethylangolensin. No β -glucuronide metabolites of either isoflavone were detected. Equol was produced in markedly fewer cats after ingestion of a soy extract tablet as a single oral bolus compared with cats consuming an isoflavone-containing diet. The detectable metabolites of the isoflavones, genistein and daidzein, in domestic cat plasma after dietary ingestion has been described in the present study for the first time. The metabolic capacity for isoflavones by domestic cats appears to be efficient, with only minimal proportions of the ingested amount detected in their unconjugated forms. This has implications for the potential of isoflavones to exert physiological activity in the domestic cat when consumed at concentrations representative of typical dietary intake

Seed production from the mixed mating system of Chesapeake Bay (USA) eelgrass (Zostera marina; Zosteraceae)

In monoecious plants, gametes can be exchanged in three ways: among unrelated genets (outbreeding), with close relatives (inbreeding), or within individuals (geitonogamous selling). These different mating systems may have consequences for population demography and fitness. The experiment presented herein used artificial crosses to examine the mating system of Chesapeake Bay, Virginia, USA eelgrass (Zostera marina L; Zosteraceae), a bisexual submerged aquatic plant that can outbreed, inbreed, and self. Genetic data indicate severe heterozygosity deficiencies and patchy genotype distribution in these beds, suggesting that plants therein reproduce primarily by vegetative propagation, autogamy, or geitonogamy. To clarify eelgrass reproductive strategies, flowers from three genetically and geographically distinct beds were hand-pollinated in outbred, inbred, and selfed matings. Fertilization success and seed production, life history stages which contribute greatly to the numeric maintenance of populations, were monitored. We found no evidence that inbreeding had negative consequences for seed production. On the contrary, selfed matings produced seeds significantly more frequently than outcrossed matings and produced significantly larger numbers of seeds than either inbred or outbred matings. These results contrast with patterns for eelgrass in other regions but might be expected for similar populations in which pollen limitation or a short reproductive season renders selfing advantageous

Facial Skin Coloration Affects Perceived Health of Human Faces

Numerous researchers have examined the effects of skin condition, including texture and color, on the perception of health, age, and attractiveness in human faces. They have focused on facial color distribution, homogeneity of pigmentation, or skin quality. We here investigate the role of overall skin color in determining perceptions of health from faces by allowing participants to manipulate the skin portions of color-calibrated Caucasian face photographs along CIELab color axes. To enhance healthy appearance, participants increased skin redness (a*), providing additional support for previous findings that skin blood color enhances the healthy appearance of faces. Participants also increased skin yellowness (b*) and lightness (L*), suggesting a role for high carotenoid and low melanin coloration in the healthy appearance of faces. The color preferences described here resemble the red and yellow color cues to health displayed by many species of nonhuman animals

Red clover-derived isoflavones and mammographic breast density: a double-blind, randomized, placebo-controlled trial [ISRCTN42940165]

INTRODUCTION: Isoflavones are hypothesized to protect against breast cancer, but it is not clear whether they act as oestrogens or anti-oestrogens in breast tissue. Our aim was to determine the effects of taking a red clover-derived isoflavone supplement daily for 1 year on mammographic breast density. Effects on oestradiol, follicle-stimulating hormone (FSH), luteinizing hormone (LH), lymphocyte tyrosine kinase activity and menopausal symptoms were also assessed. METHODS: A total of 205 women (age range 49–65 years) with Wolfe P2 or DY mammographic breast patterns were randomly assigned to receive either a red clover-derived isoflavone tablet (26 mg biochanin A, 16 mg formononetin, 1 mg genistein and 0.5 mg daidzein) or placebo. Change in mammographic breast density, serum oestradiol, FSH, LH, menopausal symptoms and lymphocyte tyrosine kinase activity from baseline to 12 months were assessed. RESULTS: A total of 177 women completed the trial. Mammographic breast density decreased in both groups but the difference between the treatment and placebo was not statistically significant. There was a significant interaction between treatment group and oestrogen receptor (ESR1) PvuII polymorphism for the change in estimated percentage breast density (mean ± standard deviation): TT isoflavone 1.4 ± 12.3% and TT placebo -9.6 ± 14.2%; CT isoflavone -5.2 ± 12.0% and CT placebo -2.8 ± 10.3%; and CC isoflavone -3.4 ± 9.7% and CC placebo -1.1 ± 9.5%. There were no statistically significant treatment effects on oestradiol, FSH, or LH (assessed only in postmenopausal women), or on lymphocyte tyrosine kinase activity. Baseline levels of menopausal symptoms were low, and there were no statistically significant treatment effects on frequency of hot flushes or other menopausal symptoms. CONCLUSION: In contrast to studies showing that conventional hormone replacement therapies increase mammographic breast density, the isoflavone supplement did not increase mammographic breast density in this population of women. Furthermore, there were no effects on oestradiol, gonadotrophins, lymphocyte tyrosine kinase activity, or menopausal symptoms

The genera Melanothamnus Bornet & Falkenberg and Vertebrata S.F. Gray constitute well-defined clades of the red algal tribe Polysiphonieae (Rhodomelaceae, Ceramiales).

Polysiphonia is the largest genus of red algae, and several schemes subdividing it into smaller taxa have been proposed since its original description. Most of these proposals were not generally accepted, and currently the tribe Polysiphonieae consists of the large genus Polysiphonia (190 species), the segregate genus Neosiphonia (43 species), and 13 smaller genera (< 10 species each). In this paper, phylogenetic relationships of the tribe Polysiphonieae are analysed, with particular emphasis on the genera Carradoriella, Fernandosiphonia, Melanothamnus, Neosiphonia, Polysiphonia sensu stricto, Streblocladia and Vertebrata. We evaluated the consistency of 14 selected morphological characters in the identified clades. Based on molecular phylogenetic (rbcL and 18S genes) and morphological evidence, two speciose genera are recognized: Vertebrata (including the type species of the genera Ctenosiphonia, Enelittosiphonia, Boergeseniella and Brongniartella) and Melanothamnus (including the type species of the genera Fernandosiphonia and Neosiphonia). Both genera are distinguished from other members of the Polysiphonieae by synapomorphic characters, the emergence of which could have provided evolutionarily selective advantages for these two lineages. In Vertebrata trichoblast cells are multinucleate, possibly associated with the development of extraordinarily long, photoprotective, trichoblasts. Melanothamnus has 3-celled carpogonial branches and plastids lying exclusively on radial walls of the pericentral cells, which similarly may improve resistance to damage caused by excessive light. Other relevant characters that are constant in each genus are also shared with other clades. The evolutionary origin of the genera Melanothamnus and Vertebrata is estimated as 75.7-95.78 and 90.7-138.66 Ma, respectively. Despite arising in the Cretaceous, before the closure of the Tethys Seaway, Melanothamnus is a predominantly Indo-Pacific genus and its near-absence from the northeastern Atlantic is enigmatic. The nomenclatural implications of this work are that 46 species are here transferred to Melanothamnus, six species are transferred to Vertebrata and 13 names are resurrected for Vertebrata

An exploration of the relationships among facial dimensions, age, sex, dominance status and personality in rhesus macaques (Macaca mulatta)

Aspects of personality in nonhuman primates have been linked to health, social relationships, and life history outcomes. In humans as well as nonhuman primates, facial morphology is associated with assertiveness, aggression, and measures of dominance status. In this study we aimed to examine the relationship among facial morphology, age, sex, dominance status, and ratings on the personality dimensions Confidence, Openness, Assertiveness, Friendliness, Activity, and Anxiety in rhesus macaques (Macaca mulatta). We measured facial width-to-height ratio (fWHR) and lower-height/full-height ratio (fLHFH) using photographs from 109 captive rhesus macaques, which observers also assessed for dominance status and personality, and explored the associations among facial morphology, age, sex, dominance status, and personality. fWHR and fLHFH personality associations depended on age category: Assertiveness was associated with higher fWHR and fLHFH, and Confidence was associated with lower fWHR and fLHFH, but all these associations were consistent only in individuals &lt;8 yr. of age. We found fWHR and fLHFH to not be consistently associated with sex or dominance status; compared to younger individuals, we found few associations with fWHR and fLHFH for individuals older than 8 yr., which may be due to limited sample size. Our results indicate that in macaques &lt;8 yr. old, facial morphology is associated with the Assertiveness and Confidence personality dimensions, which is consistent with results suggesting a relationship between fWHR and trait aggression in humans and assertiveness in brown capuchins, all of which implies that fWHR might be a cue to assertive and aggressive traits

Soya foods and breast cancer risk: a prospective study in Hiroshima and Nagasaki, Japan

The association between soya foods and breast cancer risk was investigated in a prospective study of 34 759 women in Hiroshima and Nagasaki, Japan. Women completed dietary questionnaires in 1969–1970 and/or in 1979–1981 and were followed for incident breast cancer until 1993. The analysis involved 427 cases of primary breast cancer in 488 989 person-years of observation. The risk for breast cancer was not significantly associated with consumption of soya foods: for tofu, relative risks adjusted for attained age, calendar period, city, age at time of bombings and radiation dose to the breast were 0.99 (95% CI 0.80–1.24) for consumption two to four times per week and 1.07 (0.78–1.47) for consumption five or more times per week, relative to consumption once a week or less; for miso soup, relative risks were 1.03 (0.81–1.31) for consumption two to four times per week and 0.87 (0.68–1.12) for consumption five or more times per week, relative to consumption once a week or less. These results were not materially altered by further adjustments for reproductive variables and were similar in women diagnosed before age 50 and at ages 50 and above. Among 17 other foods and drinks examined only dried fish (decrease in relative risk with increasing consumption) and pickled vegetables (higher relative risk with higher consumption) were significantly related to breast cancer risk; these associations were not prior hypotheses and, because of the large number of comparisons made, they may be due to chance. © 1999 Cancer Research Campaig