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Abstract: Desoxymethyltestosterone (DMT), also known as Madol, is a steroid recently identified to be misused as a doping agent. Since, the knowledge of functions of this substance is rather limited, it was our aim to characterise the pharmacological profile of DMT and to identify potential adverse side effects. DMT was synthesised, its purity was confirmed and its biological activity was tested. The potency of Madol (DMT) to transactivate androgen receptor (AR) dependent reporter gene expression was two times lower as compared to dihydrotestosterone (DHT). Receptor binding tests demonstrate that DMT binds with high selectivity to the AR, binding to the progesterone receptor (PR) was low. In vivo experiments in orchiectomised rats demonstrated that treatment with DMT resulted only in a stimulation of the weight of the levator ani muscle; the prostate and seminal vesicle weights remained unaffected. Like testosterone, administration of DMT resulted in a stimulation of IGF-1 and myostatin mRNA expression in the gastrocnemius muscle. In the prostate proliferation was stimulated by TP (testosteronepropionate), but remained unaffected by DMT. Remarkably, treatment with DMT, in contrast to TP, resulted in a significant increase of the heart weight. In the liver, DMT slightly stimulates the expression of the tyrosine aminotransferase gene (TAT). Our results demonstrate that DMT is a potent AR agonist with an anabolic activity. Besides the levator ani weight, DMT also modulates the gene expression in the musculus gastrocnemius. The observed stimulation of TAT expression in the liver and the significant increase of the heart weight after DMT treatment can be taken as an indication for side effects. Summarizing these data it is obvious that DMT is a powerful anabolic steroid with selective androgen receptor modulators (SARM) like properties and some indications for toxic side effects. Therefore, there is a need for a strict control of a possible misuse. [Copyright &y& Elsevier]

The knowledge about safety of phytoestrogens on proliferative endpoints in the endometrium is rather limited, particularly when low amounts of estrogens are present like in postmenopausal women. Therefore, we now studied how genistein (GEN) exposure affects proliferative endpoints in the endometrium in estrogenized animals. We investigated the effects of GEN (10 mg/(kgday) BW) on uterine proliferation and on general uterine response markers in intact female rats and ovariectomized (OVX) female rats co-treated with different doses of estradiol (E2; 1 or 4 microg/(kgday) BW). In parallel we investigated generalized hepatic effects of GEN in this co-stimulatory protocol. In agreement to our previous results, GEN treatment of OVX animals for 3 days results in a faint stimulation of the uterine wet weight. In intact animals and in OVX animals co-treated with E2 no effects of GEN on uterine wet weight were detectable. GEN treatment did not affect the uterine epithelial height in intact animals but resulted in a decrease of the protein and mRNA expression of the proliferation marker PCNA. In OVX animals co-treated with E2, GEN antagonized the E2 stimulated increase of the uterine epithelial height and epithelial PCNA expression. Besides PCNA, GEN effects on the uterine mRNA expression of IGF-1, IGF-1R, Complement C3, estrogen receptor-alpha (ERalpha) and -beta (ERbeta), as well as progesterone receptor were investigated in intact and OVX co-treated animals. Overall there was a tendency in all combinatorial groups that GEN counteracts E2 function in uterine tissue. Surprisingly, while investigating estrogenic response markers in liver, we observed very strong effects of GEN on hepatic marker gene expression. GEN significantly down-regulated CaBP9K and IGFBP1 mRNA levels in intact animals. In OVX animals hepatic CABP9K and IGFBP1 mRNA levels were not affected by E2 treatment. GEN treatment, even in combination with E2, decreased the hepatic CaBP9K expression below the levels observed in untreated animals. Interestingly co-treatment of OVX rats with low dose E2 and GEN resulted in a significant increase of IGFBP1 mRNA expression. Summarising our results we conclude that (1) GEN treatment in the presence of E2 is safe regarding proliferative responses in the endometrium of adult animals; (2) the observation of differences of the GEN activity in intact and OVX/E2 substituted animals can be taken as a hint that GEN may interact mechanistically with progestins which has to be proven in detail in future investigations and (3) the detection of strong effects of the phytoestrogen GEN on hepatic gene expression may point to the need of future investigations to rule out the possibility of adverse responses in this organ.

All post-menopausal hormone replacement therapies (HRT) aim to provide a steady mid-follicular serum concentration of estrogen, with the exception of pulsed estrogen therapy, which concentrates estradiol (E2) exposure in the few hours following administration. This study was carried out to identify and characterise cellular and molecular mechanisms specifically involved in the response of the uterus to pulsed E2. Ovariectomised Wistar rats were treated with E2 for 10 days via IV route to mimic pulsed therapy (1, 4, 10 and 250 microg/kg) or with a subcutaneous pump to mimic standard HRT (10 and 250 microg/kg). Pulsed estrogen therapy effects on uterus was revealed by general E2 sensitivity markers (C3 mRNA, progesterone receptor (PR)) from the lower dose with no over stimulation even at the highest dose conversely to what observed with continuous exposure. Uterotrophic effect of pulsed E2 (uterine weight and epithelium thickness) was observed at all dose administered but with a limited maximal effect comparable to the ranges measurable in sham animals. This data corroborates with proliferating cell nuclear antigen (PCNA) expression in the uterine epithelium used as a marker of proliferation. PCNA was significantly induced after continuous administration but only slightly after pulsed E2 (250 microg/kg). In summary, pulsed E2 leads to a more limited proliferative effect than with continuous E2 in the uterus.