ACTA ENDOCRINOLOGICA (BUC)

Testosterone influences cancer development. This in vitro experiment was exerted to determine the association of testosterone with human colorectal cancer(HT29), glioblastoma (A172) and human embryonic kidney(HEK293) cells proliferation. HT-29, A172 and HEK293 cell lines were cultured in standard growth medium, then randomly divided into control group (not exposed to testosterone) and groups exposed to 1, 10, 100 and 1000 μg/mL of testosterone. Cell viability was quantified by MTT assay. Statistical analysis was performed using ANOVA. Viability of HEK293 cells significantly increased in groups exposed to 1 μg/mL and decreased in groups exposed to 100 and 1000 μg/mL of testosterone compared to control group (P<0.05, P<0.05 and P<0.001, respectively). Viability of HT29 cells significantly increased in groups exposed to 10 and 100 μg/mL of testosterone and significantly decreased when exposed to 1000 μg/mL of testosterone compared to control group (P<0.05, P<0.001 and P<0.001, respectively). Viability of A172 cells significantly decreased in groups exposed to 100 and 1000 μg/mL of testosterone compared to control group (P<0.001). In conclusion, different doses of testosterone have enhancing or suppressive effects on HEK293, HT29 and A172 cells proliferation; according to which, considering clinical use of testosterone therapy for cancer treatment is a highly controversial issue.

Female sex steroids play considerable roles in body weight and insulin physiology.\r\nEnhanced or reduced female sex steroids affect insulin sensitivity.\r\nThe aim of the present study was to examine the effects of female sex steroids on body\r\nweight and insulin sensitivity through ovariectomy and progesterone or estradiol\r\nadministration in rats.\r\nMaterials and Methods. 7 week old female albino (Wistar) rats were used in our study.\r\nAnimals were randomly divided into control, uni-ovariectomised, bi-ovariectomised, sham,\r\nvehicle receiving sham and vehicle or hormone receiving female groups. Progesterone (20\r\nmg/kg/day) or estradiol valerate (200 &#956;g/kg/day) were injected subcutaneously, starting on the\r\nthird day after surgery and continued at daily intervals. After 4 weeks, animals were measured\r\nfor body weight and killed. Following serum collection, fasting serum insulin and glucose were\r\nmeasured and fasting glucose to insulin ratio was considered as index of insulin sensitivity\r\nwhich were compared statistically between the groups.\r\nThe results showed increased insulin sensitivity (glucose to insulin ratio) (IS) and body\r\nweight (BW) in both bi-ovariectomised (bi-ovx) (IS=14.76, BW=237.40 g) and uniovariectomised\r\n(IS=11.33, BW=225.53) rats compared with the control group (IS=9.36,\r\nBW=205.32) (p<0.01). Progesterone or estradiol replacement in bi-ovx rats was followed by\r\nincreased or decreased body weight (264.50 or 205.10) and increased or decreased insulin\r\nsensitivity (20.38 or 8.50) compared with bi-ovx rats, respectively (p<0.05). In nonovariectomised\r\nrats, administration of progesterone resulted in increased and of estradiol in\r\ndecreased body weight (220.6 g and 185.35 g) and insulin sensitivity (18.36 and 5.35)\r\ncompared with control animals (p<0.01).\r\nConclusively, our findings indicate that progesterone is enhancer and estradiol is reducer\r\nof insulin sensitivity in rats. In addition, weight gain after ovariectomy or progesterone\r\ntreatment and weight loss following estradiol treatment did not probably contribute in acting on\r\ninsulin sensitivity.

Various clinical and experimental studies indicate that gonadal hormones exert\r\nmodulatory effects on nociception and analgesia.\r\nThe aim of the present study was to investigate the role of gonadal hormones in the\r\nresponse by male and female rats to thermal nociceptive stimulation.\r\nMaterials and Methods. 7 week old albino (Wistar) rats were used in our study.\r\nAnimals were randomly divided into control, sham and ovariectomised or orchidectomised\r\ngroups. Thermal pain threshold was measured through tail immersion test before and 10, 20\r\nor 40 days after gonadectomy. The pain threshold was measured as the time required to elicit\r\na flick of the tail called analgesia time. Serum testosterone, estradiol, progesterone or\r\nprolactin levels were measured simultaneously.\r\nThe results showed that analgesia time was higher in female (5.11 min) than in male\r\n(4.93 min) intact animals (p<0.05) indicating sex difference in response to thermal\r\nnociception. Serum testosterone, estradiol or progesterone level as well as analgesia time\r\nwere not significantly reduced 10 days after gondectomy. In male animals, analgesia time\r\nwas significantly decreased (p<0.01) 20 or 40 days after orchidectomy (2.25 or 2.14 min,\r\nrespectively) compared with control rats (4.93 min). Serum testosterone concentration was\r\nsignificantly reduced (p<0.05) 20 or 40 days after orchidectomy (0.08 or 0.09 ng/mL,\r\nrespectively) compared with control serum testosterone level (2.14 ng/mL). In female rats,\r\nanalgesia time was significantly decreased (p<0.001) 20 or 40 days after ovariectomy (2.87\r\nor 2.66 min, respectively) compared with control rats (5.11 min). Serum estradiol\r\nconcentration was significantly reduced (p<0.001) 20 or 40 days after ovariectomy (3.17 or\r\n0.87 ng/mL, respectively) compared with control serum estradiol level (19.95 ng/ml). Serum\r\nprogesterone level was also decreased (p<0.001) 20 or 40 days after orchidectomy (5.27 or\r\n0.55 ng/mL, respectively) compared with control serum estradiol level (17.66 ng/mL).\r\nSerum prolactin level was not significantly enhanced during experiment indicating that there\r\nwas not heat stress influencing the procedure.\r\nConclusively, our findings clearly indicate that depletion of gonadal hormones 20 or 40 days\r\nafter gonadectomy modulates the pain-induced behavioral responses related to thermal nociception.