The alleles that are detrimental to health, especially in older age, are thought to persist in populations because they also confer some benefits for individuals (through antagonistic pleiotropy). The ApoE4 allele at the ApoE locus, encoding apolipoprotein E (ApoE), significantly increases risk of poor health, and yet it is present in many populations at relatively high frequencies. Why has it not been replaced by natural selection with the health-beneficial ApoE3 allele? ApoE is a major supplier of cholesterol precursor for the production of ovarian oestrogen and progesterone, thus ApoE has been suggested as the potential candidate gene that may cause variation in reproductive performance. Our results support this hypothesis showing that in 117 regularly menstruating women those with genotypes with at least one ApoE4 allele had significantly higher levels of mean luteal progesterone (144.21 pmol l −1 ) than women with genotypes without ApoE4 (120.49 pmol l −1 ), which indicates higher potential fertility. The hormonal profiles were based on daily data for entire menstrual cycles. We suggest that the finding of higher progesterone in women with ApoE4 allele could provide first strong evidence for an evolutionary mechanism of maintaining the ancestral and health-worsening ApoE4 allele in human populations.
1 November 2006 in Cancer Epidemiology, Biomarkers & Prevention
Variation in the levels of sex-steroid hormones results from differences in developmental conditions, adult lifestyle, and genetic polymorphism. Genes involved in sex-steroid biosynthesis have been implicated to influence levels of hormones in premenopausal women, but the results were inconclusive. We tested variation among women in levels of salivary estradiol (E2) corresponding to CYP17 genotypes. CYP17 encodes cytochrome P450c17α, which mediates two enzymes important in E2 synthesis. In contrast to the earlier studies that relied on one or a few samples for assessing the E2 levels of an individual woman, our study is based on daily collected saliva samples for one entire menstrual cycle. Sixty Polish women, ages 24 to 36 years, with regular menstrual cycles and no reported fertility problems participated in the study. Women with A2/A2 genotype had 54% higher mean E2 levels than women with A1/A1 genotype (P = 0.0001) and 37% higher than women with A1/A2 genotype (P = 0.0008). Heterozygous A1/A2 women had 13 % higher E2 levels than homozygous A1/A1 women (but this difference was significant only in a nonparametric test). Levels of E2 during the day with highest E2 (day −1) were 72% higher in A2/A2 compared with A1/A1 (P = 0.01) and 52 % higher compared with A1/A2 (P = 0.03). Our results suggest that CYP17 genotype may serve as a biomarker of endocrine function in women of reproductive age. (Cancer Epidemiol Biomarkers Prev 2006;15(11):2131–5)
BACKGROUND: Heterocyclic aromatic amines are formed during thermal processing of meat and are known to be mutagenic and carcinogenic factors, while the consumption of fruit and vegetables decreases the risk of cancer. OBJECTIVE: The aim of the study
Acetic fermentation is a method for processing plant material which has been known since antiquity. Balsamic and apple cider vinegars are investigated as antibacterial, anti-obesity, and anti-diabetic remedies. However, there is little information about vinegars fermented from aromatic herbs and edible plants. The aim of this study was to compare extracts used for culinary and medicinal purposes according to their composition, antioxidant power, and genoprotective properties. Fermented vinegars, acetic macerates, decoctions, and tinctures in 70% ethanol from raspberries, apple peels, rosehips, lavender, mint, and rose petals were prepared. Polyphenols, ascorbate, carotenoid concentrations, and antioxidant power were analyzed. The polyphenols were identified using HPLC (high-performance liquid chromatography). The genoprotective properties were measured using a comet assay on lymphocytes. Fermented vinegars were poorest in phytochemicals in comparison to tinctures, decoctions, or acetic macerates, although they contained the highest concentration of metal ions. The antioxidant abilities were correlated to the phenolic content of extract. None of the extracts induced DNA damages into lymphocytes. The rosehip and rose petal extracts revealed the highest genoprotective abilities, while mint and apple fermented vinegars and decoctions had the lowest. Fermented vinegars are not a rich source of phytochemicals and they show weak genoprotective abilities, but, in increasing demand for antioxidants, any form of phytochemical sources is an added-value in diet.
The aim of this study was to evaluate whether the differences in plasma 17beta-estradiol concentration in early and late follicular phases of the menstrual cycle can affect the level of endogenous DNA damage in lymphocytes assessed by comet assay, and whether the extent of this damage in the follicular phase is associated with the genotype of catechol-O-methyltransferase (COMT). The level of DNA damage was positively correlated with 17beta-estradiol concentration only in the late follicular phase. Subjects with the COMT L/L homozygous mutated variant revealed more DNA damage as compared to individuals with the COMT wild-type and heterozygous (H/L+HH) genotype.