EFFECTS OF MATERNAL EXPOSURE TO RICINUS COMMUNIS OIL ON GENERATIONAL REPRODUCTIVE INDICES IN WISTAR RATS

Abstract

Increasing frequency of reproductive disorders has raised concerns on effects of endocrine disruptors on reproduction. Ricinus Communis oil (RCO) possesses laxative, contraceptive, labour inducing, cosmetics and estrogenic properties. There is paucity of information on generational reproductive effects of maternal exposure to RCO despite its estrogenic properties. This study was designed to investigate the generational reproductive effects of maternal exposure to RCO in rats. Methanol extract of RCO was prepared by cold extraction and subjected to physicochemical analysis, gas chromatography and molecular spectroscopy. Acute oral toxicity was done by limit test procedure. Twenty five pregnant rats were randomly assigned to 5 groups; treated (p.o) with distilled water (control), RCO (950mg/kg) during Gestation Days (GD) 1-7, 7-14, 14-21 and 1-21 respectively. Maternal haematological, hormonal, biochemical, and histopathology of reproductive organs were assessed by conventional methods. Litter size, weight, morphometric data, Anogenital distance, pubertal age, sperm parameters, hormonal profile, organ weight and histopathology were determined in the F1 and F2 filial generations. Fertility tests, gestation, live birth, day survival and lactation indices were also determined by conventional methods. Data were analyzed using Student’s t-test at p = 0.05. No lethality was observed with RCO treatment up to 5000mg/kg. Physicochemical analysis of RCO gave values saponification (139.7) and density (0.95gm/ml) at 250C. Gas chromatography and molecular spectroscopy yielded ricinoliec acid (34.4%), methyl ricinoleate (46.7%), 9,12-octa-decadienoic acid (5.9%) and 9,17- octa-decadienal (12.9%). Serum alanine aminotransferase of GD 7-14 and 14-21 decreased significantly compared with control. Aspartate aminotransferase decreased significantly in GD1-7, 7-14, and 1-21. Total cholesterol, triglyceraldehyde and high-density lipoprotein increased while progesterone and oestrogen levels decreased significantly in RCO treated groups. The F1 female from GD1-7 and male pups from GD1-7 and 7-14, showed significant decrease in birth-weight and morphometric data. Anogenital distance decreased significantly in RCO treated F1 male (0.37±0.01, 0.39±0.02, 0.35±0.01, 0.39±0.01cm) compared with control (0.46±0.01cm). Pubertal age of F1 female decreased significantly (42.2±1.2d) compared to control (49.0±2.3d). At postnatal day 90, F1 males from RCO treated rats showed significant decrease in testis and body weight (0.98±0.03, 182.0±4.9g) compared with control (1.34±0.07, 234.0±5.1g). There were significant decreases in epididymal sperm count (99.6±6.0, 88.4±5.6, 106.8±3.7, 79±6.3 X106ml) compared with control (125.4±6.9X106ml), and motility (70.0±4.5, 64.0±2.4, 66.0±5.1, 60.0±3.2%) compared with control (93.0±1.2). Abnormal spermatozoa in RCO treated groups increased significantly (12.8±0.2, 12.2±0.2, 13.6±3.2, 15.5±2.8%) compared with control (10.5±0.2%). Serum follicle stimulating and luteinizing hormones significantly increased in F1 males of RCO treated groups. Estrogen levels significantly increased in F1 males for days 7-14. Testosterone levels significantly decreased (27.1±6.7, 13.5±3.2, 15.4±2.8, 12.1±1.5nmol/ml) compared with control (54.3±3.8nmol/ml) in RCO treated F1 males which also showed testicular interstitial oedema, reduced seminiferous tubular lumen and epididymal hypospermia. Mating, gestation, life birth, and day survival indices for control and GD 14-21 was 100% and 0% for others. Pairing F1 males from RCO treated groups and untreated females yielded 100% for all indices. Only pubertal indices were altered in F2 rats. Maternal exposure to Ricinus communis oil at early gestation periods impaired estrogenic sensitive reproductive endpoints in first generation of rats.