Serum bisphenol a concentrations showed gender differences, possibly linked to androgen levels

To investigate human exposure to bisphenol A (BPA), a widely used endocrine disruptor, we measured serum BPA concentrations and analyzed the interrelation of BPA with sex-related hormones. BPA was detected in all human sera by a novel enzyme-linked immunosorbent assay. Serum BPA concentrations were significantly higher in normal men (1.49 +/- 0.11 ng/ml; P < 0.01) and in women with polycystic ovary syndrome (1.04 +/- 0.10 ng/ml; P < 0.05) compared with normal women (0.64 +/- 0.10 ng/ml). There were significant positive correlations between serum BPA and total testosterone (r = 0.595, P < 0.001) and free testosterone (r = 0.609, P < 0.001) concentrations in all subjects and likewise between serum BPA and total testosterone (r = 0.559, P < 0.01) and free testosterone (r = 0.598, P < 0.001) concentrations in all female subjects, but not between serum BPA and other sex-related hormone concentrations in any group. These findings showed that there are gender differences in serum BPA concentrations, possibly due to differences in the androgen-related metabolism of BPA.     

Gender differences in the levels of bisphenol A metabolites in urine

The metabolism of bisphenol A (BPA), a suspected endocrine disruptor, should be considered for monitoring human exposure to BPA, because the conjugation with beta-D-glucuronide and sulfate reduces the estrogenic activity. In this study, BPA levels in 30 healthy Koreans (men, N=15, 42.6+/-2.4 years; women, N=15, 43.0+/-2.7 years) were analyzed from urine treated with/without beta-glucuronidase and/or sulfatase by an RP-HPLC with fluorescence detection. The total BPA concentrations including free BPA and the urinary conjugates were similar in men and women (2.82+/-0.73 and 2.76+/-0.54 ng ml(-1), respectively), but gender differences were found in the levels of urinary BPA conjugates. Men had significantly higher levels of BPA-glucuronide (2.34+/-0.85 ng ml(-1)) than women (1.00+/-0.34 ng ml(-1)), whereas women had higher levels of BPA-sulfate (1.20+/-0.32 ng ml(-1)) than men (0.49+/-0.27 ng ml(-1)).     

Gender difference in serum bisphenol A levels may be caused by liver UDP-glucuronosyltransferase activity in rats

Gender difference in human bisphenol A (BPA) concentrations was revealed by determining serum BPA. We studied the serum concentrations and the metabolism of BPA in rats by an HPLC system. Rat serum BPA concentrations were significantly higher in males (24.9+/-7.38 ng/ml, P=0.026, n=10) than in females (8.27+/-3.11 ng/ml, n=10), as in humans. The resultant enzyme reaction products of BPA glucuronidation in the rat liver microsomes fraction were analyzed by an HPLC system. The ratio of BPA glucuronidation in the microsome reaction was significantly higher (P=0.015) in female than in male rats. The mRNA expression of UDP-glucuronosyltransferase 2B1 (UGT2B1), an isoform of UGT related to BPA glucuronidation, in the rat liver was analyzed by a real-time quantitative RT-PCR. The relative expression level of UGT2B1 mRNA was significantly higher (P<0.001) in female than in male rat livers. The gender difference in serum BPA concentrations may be explained by the difference in clearance based on the UGT activities.     

Inhibition by wheat sprout (Triticum aestivum) juice of bisphenol A-induced oxidative stress in young women

For health of future generation, fertile young women should be monitored for exposure of endocrine disrupting chemicals (EDCs). Among EDCs, bisphenol A (BPA) is suggested to induce reactive oxygen species (ROS) which play an important role in pathologies of female diseases such as endometriosis. On the other hand, previous studies suggested that sprouts of wheat (Triticum aestivum) have antimutagenicity and antioxidant activity. We performed the 2 weeks intervention of wheat sprout juice (100ml/day) to investigate its effects on BPA-exposure and -oxidative toxicity in young women (N=14, age=24.4±4.0). Geometrical mean of urinary BPA levels was 1.81 (GSTD, 4.34)μg/g creatinine. We observed that irregular meals significantly increased levels of urinary BPA approximate 3 times (p=0.03). In addition, we found BPA-induced oxidative stress is correlated with levels of 8-hydroxydeoxyguanosine (8-OHdG) or malondialdehyde (MDA) levels (p=0.18 or 0.03, respectively). We also observed a continuous reduction of urinary BPA during the wheat sprout intervention (p=0.02). In summary, our data suggested potential detoxification of wheat sprouts on BPA-toxicity via antioxidative and interference of absorption, distribution, metabolism and excretion (ADME)-mediated mechanisms in young women.     

Amniotic fluid cathelicidin in PPROM pregnancies: from proteomic discovery to assessing its potential in inflammatory complications diagnosis

Background

Preterm prelabor rupture of membranes (PPROM) complicated by microbial invasion of the amniotic cavity (MIAC) leading to histological chorioamnionitis (HCA) significantly impacts perinatal morbidity. Unfortunately, no well-established tool for identifying PPROM patients threatened by these disorders is available.

Methodology/Principal Findings

We performed an unbiased exploratory analysis of amniotic fluid proteome changes due to MIAC and HCA. From among the top five proteins that showed the most profound and significant change, we sought to confirm results concerning cathelicidin ({"type":"entrez-protein","attrs":{"text":"P49913","term_id":"1706745","term_text":"P49913"}}P49913, CAMP_HUMAN), since an ELISA kit was readily available for this protein. In our exploratory proteomic study, cathelicidin showed a ∼6-fold higher concentration in PPROM patients with confirmed MIAC and HCA. We verified significantly higher levels of cathelicidin in exploratory samples (women without both MIAC and HCA: median 1.4 ng/ml; women with both conditions confirmed: median 3.6 ng/ml; p = 0.0003). A prospective replication cohort was used for independent validation and for assessment of cathelicidin potential to stratify women with MIAC leading to HCA from women in whom at least one of these conditions was ruled out. We confirmed the association of higher amniotic fluid cathelicidin levels with MIAC leading to HCA (the presence of both MIAC and HCA: median 3.1 ng/ml; other women: median 1.4 ng/ml; p<0.0001). A cathelicidin concentration of 4.0 ng/ml was found to be the best cut-off point for identifying PPROM women with both MIAC and HCA. When tested on the validation cohort, a sensitivity of 48%, a specificity of 90%, a likelihood ratio of 5.0, and an area under receiver-operating characteristic curve of 71% were achieved for identification of women with MIAC leading to HCA.

Conclusions

Our multi-stage study suggests cathelicidin as a candidate marker that should be considered for a panel of amniotic fluid proteins permitting identification of PPROM women with MIAC leading to HCA.     

Twice single doses of 100,000 IU of vitamin D in winter is adequate and safe for prevention of vitamin D deficiency in healthy children from Ushuaia, Tierra Del Fuego, Argentina

In order to improve vitamin D status of children from Ushuaia (55°S), at the South of Argentina, double supplementation with 100.000 IU of vitamin D was administered at the beginning of winter (March 2004), and 3 months later during winter (June 2004). In 2004, serum 25-hydroxyvitamin D (25OHD) was measured before the first supplementation, a month after, and 3 months after receiving the second supplementation (March, April and September). We studied 18 healthy children from Ushuaia, age (mean ± S.D.) 7.3 ± 4.4 years old (range 1.2–14.6), seven girls and 11 boys. Before treatment, serum 25OHD was 29.3 ± 5.9 ng/ml. It increased significantly 1 month after the first supplementation (April): 35.3 ± 4.4 ng/ml (p < 0.001), and decreased significantly 3 months after the second supplementation: 22.4 ± 4.6 ng/ml (September (p < 0.001). No child was neither deficient (<10 ng/ml) nor insufficient (10–15 ng/ml) of vitamin D. On April, a month after the first supplementation, no children had vitamin D intoxication levels (>50 ng/ml). These results disclosed that to prevent vitamin D deficiency for children at zones of risk at the south of our country, double supplementation of 100,000 IU of vitamin D during autumn and winter, would be adequate and safe.     

Metabolic activation of benzo(a)pyrene by human amniotic fluid

The in vitro activation of benzo(a)pyrene was studied in amniotic fluid from ten 4-month pregnant women. Benzo(a)pyrene monooxygenase and epoxide hydrolase activities were in the same range in amniotic fluid as in human liver. Glutathione epoxide transferase activity was markedly lower than in hepatocytes. Human amniotic fluid also catalyzed the formation of hydrocarbon metabolites mutagenic to Salmonella typhimurium TA98 (Ames system). Profiles of amniotic fluid aromatic hydrocarbons from non smokers exhibited low benzo(a)pyrene concentration (less than 0.1 ng/ml).     

Falls are associated with decreased renal function and insufficient calcitriol production by the kidney

In a double blind placebo controlled 3-year osteoporosis study in elderly women, we collected prospective data on falls. The study population comprised 489 normal elderly women aged 65–77 years randomized to four groups: placebo, calcitriol 0.25 mcg b.i.d., conjugated equine estrogens (0.625 mg/day) and calcitriol + estrogen. Falls occurred in 57% of all women.

Using a Poisson regression model, the placebo group with low GFR-creatinine clearance (CrCl < 60 ml/min) had 60% more falls compared to the group with CrCl ≥ 60 ml/min. Further sub group analyses showed that there is no increased risk of falls with CrCl 60–70, 70–80 and >90 ml/min. Calcitriol treatment significantly reduced the number of falls by 50% (OR = 0.5, 95% CI: 0.4–0.9, p = 0.010) compared to placebo in the low CrCl group.

The group with lower CrCl had lower calcium absorption (p < 0.001), lower serum 1,25-dihydroxyvitamin D (1,25(OH)₂D) (p < 0.001) and normal serum 25OHD suggesting that there is decreased conversion of 25OHD to 1,25(OH)₂D by the aging kidney. It is postulated that the decrease in falls on calcitriol therapy is related to an increase in serum 1,25(OH)₂D, upregulation of VDR and improvement in muscle strength although one cannot exclude an effect on the central nervous system.     

The effect of follicle-stimulating hormone on follicular development, granulosa cell apoptosis and steroidogenesis and its mediation by insulin-like growth factor-I in the goat ovary

The effect of FSH on goat follicular development, granulosa cell apoptosis and steroidogenesis and its mediation by insulin-like growth factor (IGF)-I were studied through both in vivo and in vitro experiments. The FSH treatment was begun on Day 9 after estrus and consisted of injections twice a day for 3 days in decreasing doses (7.5–7.5–5.0–5.0–2.5–2.5 mg). Does in both treatment and control groups were slaughtered for ovaries on Day 12. Granulosa cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). Expression of IGF-I and IGF-II mRNA was determined by RT–PCR, while concentrations of progesterone (P4), estradiol (E2), IGF-I and IGF-II were measured by radioimmunoassay (RIA). Following parameters increased significantly (P<0.05) after the FSH treatment: follicle number (5.0±1.5 versus 9.0±2.0 per ovary), the level of E2 (0.1±0.1 ng/ml versus 0.7±0.2 ng/ml), the E2/P4 ratio (0.7±0.4 versus 4.7±3.0) and the concentrations of IGF-I (0.5±0.2 ng/ml versus 119.4±15.1 ng/ml) and IGF-II (0.12±0.03 ng/ml versus 40.9±18.7 ng/ml) in follicular fluid of the medium sized (3–5 mm) follicles and in the ovarian cortex the relative quantity of IGF-I mRNA (0.37±0.17 versus 0.90±0.12 Max OD). In contrast, the ratio of apoptotic granulosa cells in these follicles was reduced significantly (0.53±0.1 versus 0.10±0.01, P<0.05). In large (>5 mm) follicles, however, only the follicle number (2.3±0.7 versus 7.0±1.5 per ovary) and the level of IGF-I (38.4±11.0 ng/ml versus 87.3±13.9 ng/ml) increased significantly (P<0.05), whereas other values did not change. In vitro culture of granulosa cells showed that FSH significantly (P<0.05) enhanced IGF-I production (12.7±2.1 ng/ml versus 26.±21.9 ng/ml) by these cells, and both FSH and IGF-I reduced the ratios of apoptotic cells (from 0.7±0.07 to 0.3±0.1 and 0.2±0.04, respectively) and the effect was additive when both were used together. H89, the PKA pathway inhibitor, blocked the effect of FSH on granulosa cell apoptosis and IGF-I production in vitro. These results indicated that FSH mainly enhanced the development of medium sized follicles in the goat by suppressing the apoptosis of granulosa cells via increasing production of IGF-I and steroids, possibly through the PKA pathway.     

Age-related changes in 11β-hydroxyandrostenedione concentration in normal and osteoporotic women

The secretion of dehydroepiandrosterone (DHEA) and its sulfate is known to decline gradually with advancing age. Furthermore DHEA is known to be significantly lower in osteoporotic subjects than in normals. Recently 11β-hydroxyandrostenedione (11-OHA) has been proposed as an important indicator of the adrenal source of hormone excess in different hyperandrogenic states. In the present study we measured 11-OHA in 224 normal women aged 20–79 yr and 130 osteoporotic women aged 40–79 yr. RIA of 11-OHA was performed with highly specific antiserum raised in rabbits.

The mean 11-OHA serum concentration was 2.20±0.90 ng/ml in normal women and 1.75±0.58 ng/ml in osteoporotic women. In contrast to DHEA there was no age-related decrease in 11-OHA serum concentrations in normal and osteoporotic women. Osteoporotic subjects showed statistically significantly lower 11-OHA serum concentrations than normal women. Therefore low serum 11-OHA might represent a further risk factor for osteoporosis.