Severe abnormalities in the reproductive organs of mice caused by chemical substances contained in heavy oil

Estrogenic activity of bio-degradation products of C-heavy oil revealed by gene-expression profiling using an oligo-DNA microarray system

Degradation of heavy oil by bacteria to decompose organic compounds such as aliphatic and aromatic hydrocarbons has been used in bioremediation. However, the biological and environmental effects of the degradation products including intermediates are still not clear. Here, we monitored the degradation of C-heavy oil by analyzing the products formed in cultures with oil-degrading bacteria (complex microbes or a single bacterial strain). Furthermore, proliferation assays using breast cancer MCF-7 cells and gene-expression profiling of MCF-7 cells using oligonucleotide-DNA microarrays were performed to evaluate the estrogenic activity of the degradation products. While the products did not show any significant cell-proliferative activity, the oil samples cultured for longer periods (2-3 months), whether cultured with mixed microbes or a single bacterial strain, showed gene-expression profiles similar to that of 17β-estradiol (E2). These results suggest that oil-degradation products have estrogenic activity, and estrogen-like components could possibly be produced during the degradation process.

Heavy oil fraction induces the dysplastic sperm in male mouse

Heavy oil is one of the most serious pollutants in marine ecosystem. The poisonous influences of the chemical substances contained in heavy oil on many kinds of marine organisms are widely studied. However, the influence of the chemical compounds in heavy oil on our health has not been cleared yet. In order to reveal the poisonous influences of these chemical compounds on mammalian reproductive system, water-soluble fraction (WSF) extracted from heavy oil was administrated to mice for 2 weeks. WSF-administrated mice were crossed with either WSF- or distilled water-administrated group for mating experiment. When WSF-administrated male mice were used as a father, it reduced not only mating ratio, but also neonatal male ratio. The numbers of sperms of WSF-administrated male mice were decreased. In addition, abnormality of sperms such as bent or twisted tail was increased approximately 6-fold by WSF intake. The level of testosterone in serum from WSF-administrated mice was lower than that from control mice. Testosterone is the most important for the spermatogenesis in vertebrate. It is supposed from these findings, the decrease in the number of sperms may relate with the reduction of sex hormone level in serum. It is suggested from these results that the chemical substances in WSF affected the sperm function in reproductive system of male mice.

Serum biochemical analysis to indicate pathogenic risk on mouse Mus musculus exposure to source of drinking water

The 18 biochemical parameters of serum were measured to analyze the pathogenic risks of the Yangtze River Source of Drinking Water in Nanjing area (YZR-SDW-NJ) on mouse Mus musculus for protection of human health in this research. The male mice Mus musculus were sampled and fed with YZR-SDW-NJ for 90 days then the eighteen serum biochemical levels were measured with Automatic Biochemical Analysis/RerLi 600. And the parameter data were treated by One-Way ANOVA statistic approach. The results showed that five parameter levels for the sample group mice were different from those for the control group significantly (0.01 < P or 0.05 < P). Four 4 of the 5 altered parameter levels were decreased including glutamate pyruvate transaminase 38% lower, glutamine-oxaloacetic transaminase 24% lower, triglyceride 76% lower and cystatin C 73% lower, only creatinine level was 26% higher than that in the control group. The data suggest that YZR-SDW-NJ had toxicity on the mouse and the organic pollutants in YZR-SDW-NJ might lead to liver, kidney, cardiovascular and metabolic pathogenic risks on the human beings. The results might be cited as evidence to control pollutants in the source water for the protection of NJ people's health.

Oral administration of paraquat perturbs immunoglobulin productivity in mouse

Paraquat is one of the most widely used herbicides in the world and has been known to injure lungs, liver and skin in animals and human. Hence, it is important to understand the manner of paraquat in mammals. We studied the effect of paraquat on the immune function of mouse in vitro and in vivo. When splenocytes were cultured in vitro with various concentrations of paraquat, IgA productivity was not affected while IgG and IgM productivity decreased. On the other hand, Oral administration of paraquat for 1, 2 or 3 weeks increased IgA level but decreased IgM levels in serum of mice. Similarly IgA productivity increased while IgM productivity decreased. These results suggest that paraquat perturbs the lymphocytes immunoglobulin productivity in an immunoglobulin class-dependent manner.