Effects of testosterone and estradiol on stress-induced adrenal and hippocampal weight changes in female rats.

OBJECTIVE: To examine the impact of circulating testosterone (T) and the T/Estradiol (T/Ediol) ratio on chronic stress-induced changes of adrenal and hippocampal weight during proestrus (PE) and estrus (E) in female rats. DESIGN: Stress was composed of repeated vaginal smear screening (VSS) and measured by the emotional reactivity score (ERS). Adrenal and hippocampal weight and the T, Ediol and T/Ediol ratio were assessed in PE and E controls as well as 20 h after sham or left adrenalectomy performed on diestrus-2 (DE-2) and PE, respectively. T was measured in ovariectomized (OVX) rats treated with estradiol benzoate (EB) or vehicle (VEH) and in non-OVX EB-treated rats. RESULTS: In OVX rats EB treatment increased adrenal weight and T levels. After separation of VEH- and EB-treated rats into the low and high T-range (below and above the mean, respectively), it was observed that higher T was accompanied by higher adrenal weight in EB- compared to VEH-treated rats only in the low T-range. Non-OVX EB-treated rats with high T had lower adrenal weight compared to low T. Cycling rats assigned to the high T-range presented higher T/Ediol ratio but similar ERS and Ediol levels compared to rats in the low T-range, and were characterized by reduced adrenal weight, higher hippocampal weight and prevalence of PE versus E. CONCLUSIONS: High T and high T/Ediol ratios are prominent in PE compared to E and exert a protective effect on hippocampal neuronal degeneration after similar chronic stress through T-mediated lessening of stress response thus counteracting the stress-promoting effects of Ediol.

Is drug utilization in Greece sex dependent? A population-based study.

Despite scarce data pertaining to prescription drug sales in Greece, the lack of large-scale epidemiological studies has made it difficult to elaborate on putative differences regarding drug consumption patterns between the two sexes. Herein, we sought to investigate whether sex may have an impact on medication trends of the Greek population. The data reported are part of a survey conducted under the auspices of the National Center for Social Research. Information was collected from 2499 Athenian citizens. Probability of drug use was assessed through Pearson chi-square (χ(2) ) test and logistic regression was implemented to clarify whether sex or other socio-economic and morbidity factors may influence drug utilization. Women consumed more drugs as compared to men. Sex proved to be a differentiating factor influencing the use of analgesic/non-steroidal anti-inflammatory drugs, cardiovascular, anxiolytic and antidepressant drugs, as well as drugs for the treatment of thyroid diseases and osteoporosis. Present results further implicate other socio-economic factors (e.g. education, employment and financial status) in the harnessing of drug use in Greece. To the best of our knowledge, this is the largest pharmacoepidemiological study to report that Greek women consume more drugs and present different medication patterns, as compared to men. Further research is considered imperative in order for the awareness of prescribers, policy-makers and the general public on this sensitive matter to be increased.

The effects of rivastigmine plus selegiline on brain acetylcholinesterase, (Na, K)-, Mg-ATPase activities, antioxidant status, and learning performance of aged rats.

UNLABELLED: We investigated the effects of rivastigmine (a cholinesterase inhibitor) and selegiline ((-)deprenyl, an irreversible inhibitor of monoamineoxidase-B), alone and in combination, on brain acetylcholinesterase (AChE), (Na(+), K(+))-, Mg(2+)-ATPase activities, total antioxidant status (TAS), and learning performance, after long-term drug administration in aged male rats. The possible relationship between the biochemical and behavioral parameters was evaluated. METHODS: Aged rats were treated (for 36 days) with rivastigmine (0.3 mg/kg rat/day ip), selegiline (0.25 mg/kg rat/day im), rivastigmine plus selegiline in the same doses and way of administration as separately. Aged and adult control groups received NaCl 0.9% 0.5 ml ip. RESULTS: TAS was lower in aged than in adult rats, rivastigmine alone does not affect TAS, decreases AChE activity, increases (Na(+), K(+))-ATPase and Mg(2+)-ATPase activity of aged rat brain and improves cognitive performance. Selegiline alone decreases free radical production and increases AChE activity and (Na(+), K(+))-ATPase activity, improving cognitive performance as well. In the combination: rivastigmine seems to cancel selegiline action on TAS and AChE activity, while it has additive effect on (Na(+), K(+))-ATPase activity. In the case of Mg(2+)-ATPase selegiline appears to attenuate rivastigmine activity. No statistically significant difference was observed in the cognitive performance. CONCLUSION: Reduced TAS, AChE activity and learning performance was observed in old rats. Both rivastigmine and selesiline alone improved performance, although they influenced the biochemical parameters in a different way. The combination of the two drugs did not affect learning performance.

Reversible plasma testosterone levels reduction after gentamicin administration and freund's adjuvant arthritis in rats.

The present study was undertaken in order to investigate the influence of gentamicin on plasma testosterone levels of healthy and with Freund's adjuvant arthritis rats. Gentamicin (40 mg/day for 4 days) induced significant decrease of testosterone levels in comparison with the control group (P<0.025). Intraperitoneal calcium administration (30 mg/ kg bw) prevented gentamicin effect and maintained testosterone levels to that of the control. Decreased testosterone levels were also observed in gentamicin received Freund's adjuvant arthritic rats, in the acute stage of the inflammatory disease (P<0.025), and in the acute stage of Freund's adjuvant arthritis (P<0.001). It is concluded that the administration of gentamicin decreases plasma testosterone levels without any effect on body and seminal vesicles weight. Calcium loading counteracts gentamicin reducing effect on plasma testosterone levels. Freund's adjuvant arthritis influences the function of body and seminal vesicles as it was shown by the reduction of testosterone levels, body and seminal vesicles weight during the acute phase of the inflammatory disease. In any case the effect was reversible.

Greek plant extracts exhibit selective estrogen receptor modulator (SERM)-like properties.

To prevent bone loss that occurs with increasing age, nutritional and pharmacological factors are needed. Traditional therapeutic agents (selective estrogen receptor modulators or SERMs, biphosphonates, calcitonin) may have serious side effects or contraindications. In an attempt to find food components potentially acting as SERMs, we submitted four plant aqueous extracts derived from Greek flora (Sideritis euboea, Sideritis clandestina, Marticaria chamomilla, and Pimpinella anisum) in a series of in vitro biological assays reflective of SERM profile. We examined their ability (a) to stimulate the differentiation and mineralization of osteoblastic cell culture by histochemical staining for alkaline phosphatase and Alizarin Red-S staining, (b) to induce, like antiestrogens, the insulin growth factor binding protein 3 (IGFBP3) in MCF-7 breast cancer cells, and (c) to proliferate cervical adenocarcinoma (HeLa) cells by use of MTT assay. Our data reveal that all the plant extracts studied at a concentration range 10-100 microg/mL stimulate osteoblastic cell differentiation and exhibit antiestrogenic effect on breast cancer cells without proliferative effects on cervical adenocarcinoma cells. The presence of estradiol inhibited the antiestrogenic effect induced by the extracts on MCF-7 cells, suggesting an estrogen receptor-related mechanism. In conclusion, the aqueous extracts derived from Sideritis euboea, Sideritis clandestina, Marticaria chamomilla, and Pimpinella anisum may form the basis to design "functional foods" for the prevention of osteoporosis.