Naslov
Low iron diet and cadmium exposure disrupt steroidogenesis in the rat

Autori
Piasek, Martina ; Laskey, John W. ; Kostial, Krista ; Blanuša, Maja ; Ferrell, Janet M.

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
Proceedings of the Tenth International Symposium on Trace Elements in Man and Animals 10 / Roussel, Anne-Marie ; Anderson, Richard A. ; Favier Alain E. - New York (NY) : Kluwer Academic Publishers ; Plenum Publishers, 2000, 809-812

Skup
10th International Symposium on Trace Elements in Man and Animals TEMA 10

Mjesto i datum
Évian-les-Bains, Francuska, 02.05.1999. - 07.05.1999

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
cadmium ; estradiol ; iron ; ovary ; placenta ; progesteron ; steroid hormones

Sažetak
The existing evidence on the association of cadmium (Cd) exposure and female reproduction is limited and inconclusive. There are generally insufficient data on the effects of Cd with concomitant nutritional iron (Fe) deficiency, a state common in women of childbearing age. The study was conducted on timed-pregnant 60-days-old Sprague-Dawley rats fed semisynthetic pelleted laboratory diets (Harlan Teklad, Madison, WI) with either high Fe (240 ppm) or low Fe (10 ppm) content. From gestation day one, the dams were continuously exposed to Cd (chloride) at a total dose of 0, 3 or 5 mg/kg b.wt. during 19 days (minimum 7 animals per group) by s.c.implanted osmotic mini pumps. On gestation day 19, the dams were exsanguinated by cardiac puncture in CO2 anaesthesia. Serum, right ovaries and two placentas were taken for evaluation of steroid hormone production. Progesterone and estradiol serum concentrations, progesterone, testosterone and estradiol productions in the minced whole ovary cultures, and progesterone and testosterone productions in the placental cultures were analysed by specific radioimmunoassay. Data were statistically evaluated by analysis of a variance in the general linear models procedure using the Statistical Analysis System with low Fe diet and Cd exposure as two independent variables. With low Fe diet, body weights of the dams, maternal and foetal haematocrits, and number of viable foetuses were decreased, and late resorptions were increased. Despite Cd treatments, all dams on low Fe diet had reduced serum progesterone concentrations (53.3+1.49 vs. 62.7+1.60 ng/ml in control). No effect of either low Fe diet or Cd exposure was observed on ovarian steroid production and no Cd effects were found on general health of the dams and/or fetal viability. Low Fe diet and Cd effects on placental steroidogenesis were additive and linear with significant reduction in placental progesterone production at 5 mg/kg dose (9.48+0.9 vs. 12.8+1.0 ng/g/hr in control). With subchronic Cd exposure, estradiol serum concentrations were decreased, and this effect was linear (13.4+3.12 and 9.19+1.98 at 3 and 5 mg/kg dose vs. 17.0+1.91 pg/ml in control). With both high and low Fe diets, increase in Cd concentrations in the maternal placentas of exposed dams was dose-related. Average placental Fe concentrations were greater in the rats fed high Fe feed comparing to the low Fe diet group, no matter the Cd exposure. Our findings suggest that subchronic Cd exposure and concomitant low Fe diet may disrupt placental steroid production and concentrations of circulating steroid hormones in late pregnancy.

Izvorni jezik
Engleski

Znanstvena područja
Javno zdravstvo i zdravstvena zaštita

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