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Journal Article 2003; 24(3-4): 141-147 PubMed PMID: 14523347 Citation  Keywords:  Animals, Brain Chemistry:genetics, Estrogens:physiology, Female, Humans, Male, Neurodegenerative Diseases:physiopathology, Receptors, Estrogen:genetics,.   

: In trying to rectify the differences in the risk, onset, and progression of neurodegenerative diseases between men and women, the gonadal hormone estrogen has been the primary focus of investigation for many years. Although this gender difference may encompass disparate and overlapping reasons, estrogen and signaling events mediated by its receptor have been shown to be neuroprotective in a number of neurodegenerative disease models such as Alzheimer's, Parkinson's, and Schizophrenia. Although data from human studies remains highly controversial, a large body of research findings suggests that this hormone plays a pivotal role in retarding and preventing the formation of neurodegenerative diseases through its receptor. By activating common intracellular signaling pathways and initiating "cross talk" with neurotrophins, estrogen plays an influential role in neuronal survival from injuries induced by ischemia or other environmental insults. Gaining a better understanding of these estrogen receptor mediated neuroprotective mechanisms may lead to new therapeutic strategies for the treatment or prevention of neurodegenerative diseases....

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Journal Article 2002; 23(Suppl 2): 37-42 PubMed PMID: 12163846 Citation  Keywords:  Aging:metabolism, Animals, Estrogen Replacement Therapy, Estrogens, Non-Steroidal:therapeutic use, Female, Homeostasis:physiology, Humans, Isoflavones, Menopause:physiology, Neurosecretory Systems:metabolism, Phytoestrogens, Plant Preparations, Receptors,.   

: Endocrine modulation by natural and synthetic chemicals and the eventually resulting beneficial or adverse effects for human and animal health are controversially debated not only among scientists but particularly in the public. Most information is available on so-called environmental estrogens, however the amount of information on substances interfering with other hormonal axes steadily increases, particularly on those exhibiting (anti)androgenic activities. The aim of this paper is to summarize existing data and to give an overview on the potential pathways leading to interferences of environmental hormones with homeostasis and eventually resulting health effects. Experimental evidence suggests the hypothesis that fetal and neonatal organisms may be at risk if exposed to environmental estrogens. In contrary, it appears as if phytoestrogens, particularly those with selective estrogen receptor modulator- (SERM-)like activities have the potential to be useful in medical application, both as dietary means and as pharmaceuticals. Lacking valid information about the detailed analysis of the molecular mode of action for environmental estrogens, the possibility for an ultimate classification of environmental estrogens in "dangerous endocrine disruptors" and phytoestrogens in "useful pharmaceuticals" cannot be supported conclusively. Nevertheless both activities are likely....

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Journal Article 2018; 39(4): 294-298 PubMed PMID: 30531698 Citation  Keywords:  Benzhydryl Compounds:toxicity, Comet Assay, DNA:drug effects, DNA Breaks, Double-Stranded:drug effects, DNA Damage:drug effects, Endocrine Disruptors:toxicity, Environmental Pollutants:toxicity, Estrogens, Non-Steroidal:toxicity, Free Radical Scavengers:t.   

OBJECTIVES: Bisphenol A (BPA) is an endocrine disruptor which has been shown to be a harmful compound for living organisms. It is the main component of the most commonly used plastic products such as plastic bottles, food cans and containers or dental fillings, and other medical aids. Recently, it has become a new environmental pollutant. The current knowledge about the BPA effects (including genotoxic one) on different cells is in many cases contradictory. Thus, the aim of the paper is to study the potential genotoxic effect of BPA. METHODS: An observation of the genotoxic activity of BPA on human lymphocytes was evaluated by using the alkaline comet assay and a modified comet assay with bacterial DNA repair enzyme Fpg. The potential DNA-protective effect of BPA was tested by using the DNA-topology assay. RESULTS: The results show that rising concentrations of BPA increase the risk of DNA double-strand breaks and modified purines in human lymphocytes. Interestingly, BPA shows an ability to protect plasmid DNA from the damage of iron ions in cell-free system. CONCLUSIONS: BPA itself does not induce genotoxic effect to DNA. However, BPA treatment of human lymphocytes leads to the induction of DNA damage. The proposed mechanism of BPA action in the human lymphocytes could be mediated by cell metabolism that induces an oxidative stress and ROS formation. ROS subsequently attack DNA and thus induce DNA damage. According to our results, BPA can be included in the group of substances with dual effects involving genotoxic and DNA-protective activity....

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