Deleterious effect of gestagens from wastewater effluent on fish reproduction in aquatic environment: A review

Gestagens are common pollutants accumulated in the aquatic ecosystem. Gestagens are comprised of natural gestagens (i.e. progesterone) and synthetic gestagens (i.e. progestins). The major contributors of gestagens in the environment are paper plant mill effluent, wastewater treatment plants, discharge from pharmaceutical manufacturing, and livestock farming. Gestagens present in the aquatic environment interact with progesterone receptors and other steroid hormone receptors, negatively influencing fish reproduction, development, and behavior. In fish, the gonadotropin induces 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) production, an important steroid hormone involved in gametogenesis. DHP interacts with the membrane progestin receptor (mPR), which regulates sperm motility and oocyte maturation. Gestagens also interfere with the hypothalamic-pituitary-gonadal (HPG) axis, which results in altered hormone levels in fish. Moreover, recent studies showed that even at low concentrations exposure to gestagens can have detrimental effects on fish reproduction, including reduced egg production, masculinization, feminization in males, and altered sex ratio, raising concerns about their impact on the fish population. This review highlights the hormonal regulation of sperm motility, oocyte maturation, the concentration of environmental gestagens in the aquatic environment, and their detrimental effects on fish reproduction. However, the long-term and combined impacts of multiple gestagens, including their interactions with other pollutants on fish populations and ecosystems are not well understood. The lack of standardized regulations and monitoring protocols for gestagens pollution in wastewater effluent hampers effective control and management. Nonetheless, advancements in analytical techniques and biomonitoring methods provide potential solutions by enabling better detection and quantification of gestagens in aquatic ecosystems.

Cytogenetic biomarkers in detection of genotoxic effects of gestagens in peripheral blood lymphocytes in vitro and in vivo

Gestagens are the most frequently used steroid hormones in hormone-replacement therapy in the treatment of threatened miscarriage during the first trimester of pregnancy. This therapy has been applied in a large number of women with threatened abortion, despite various degrees of success of its efficacy. Genetic factors play a key role in miscarriages, especially in the initial stages. Cytogenetic biomarkers such as micronucleus (MN) test, chromosomal aberrations (CAs), and sister chromatid exchanges (SCEs) provide information on DNA damage. Cytogenetic markers detecting DNA damage have become very popular and useful in analysing genetic risk associated with hormone-replacement therapy. Cytogenetic studies presented heterogenous information. In many in vitro studies synthetic gestagens have been shown to induce genotoxic effects, and it was evaluated using three cytogenetic biomarkers. Genotoxic effects of gestagens have also been confirmed in in vivo studies that were conducted involving patients who received gestagen therapy during pregnancy and their newborns. However, some studies have shown that hormone-replacement therapy does not have genotoxic effects. In this paper, we summarize the results from previous studies. We also describe the usefulness of these biomarkers in the detection of genotoxic effects of hormone-replacement therapy.

Rapid relapse in depression following initialization of oral contraception with ethinyl estradiol and chlormadinone acetate

OBJECTIVE

Female sexual hormones (estrogens and gestagens) may affect neurocognitive functioning and mood. Thus, the use of oral hormonal contraceptives (OHC) bears the risk of psychiatric adverse drug reactions such as depression and psychosis. However, the available empiric evidence regarding this connection is conflicting, and, moreover, female sex hormones seem to feature also mood-stabilizing and antidepressive effects. Hence, individual susceptibility factors and preparation-specific pharmacologic properties might play a pivotal role in the development of mood disturbances related to OHC. Single case reports provide empiric data for further systematic approaches.

METHODS

A clinical case is presented and discussed.

RESULTS

A 36-year-old female patient with recurrent major depressive disorder developed rapid relapse in depression after initialization of OHC with ethinyl estradiol 30 μg/chlormadinone acetate 2 mg. This OHC combination was described to particularly feature positive effects on depressive mood.

CONCLUSIONS

OHC may induce serious mood disturbances and should be administered with care, particularly in patients with affective disorders.

[Breeding management of black rhinos (Diceros bicornis michaeli) in Magdeburg Zoo]

OBJECTIVE

The African black rhino is an endangered species. In Germany there are only five zoos where this species is kept and breeding has not been successful in all of them. In Magdeburg Zoo the last birth occurred in December 2005, and during the following years, no matings could be observed. During the construction of a new enclosure to enable a more natural mating behaviour, the reproduction status of the rhino cows was evaluated and a hormonal treatment was performed.

MATERIAL AND METHODS

Since 2009, faecal samples from two rhino cows (Diceros bicornis michaeli; "Mana", 30 years old, and "Maleika", 17 years old) were collected periodically, and the pregnanediol-glucuronide (PdG) and oestradiol concentrations were determined using enzyme immunoassay and radioimmunoassay, respectively. Following evaluation of the results, both cows were treated for 12 days with Regumate® Equine, a synthetic progesterone, during the period of PdG-dominance.

RESULTS

"Mana" accepted the bull 11 days after completion of the hormonal treatment, and in December 2011 gave birth to a healthy calf. "Maleika" had her first ever oestrus 13 days after completion of the medication and also accepted the bull. Thereafter, she had two regular oestrus cycles with normal mating behaviour. Her first calf was born in July 2012.

CONCLUSION AND CLINICAL RELEVANCE

The causal treatment of both cows, following a long period of infertility, with synthetic progesterone led to their pregnancy and the birth of healthy calves. The commercial product Regumate® Equine is appropriate to stimulate the sexual cycle in temporarily infertile black rhinos. Attention should be paid to the timing of the medication and the required dose.