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M P Dain - One of the best experts on this subject based on the ideXlab platform.
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A comparison study of lipid and Androgen Metabolism with triphasic oral contraceptive formulations containing norgestimate or levonorgestrel
Acta Obstetricia et Gynecologica Scandinavica, 1992Co-Authors: A Janaud, J Rouffy, D Upmalis, M P DainAbstract:The effects of norgestimate triphasic (Ortho Tri-Cyclen®, Tri-Cilest®) and levonorgestrel triphasic (Triphasil®) formulations on lipid and Androgen Metabolism were assessed in a study of 66 healthy women treated through six menstrual cycles. Levels of the following were measured: cholesterol and its subfractions, triglycerides. carrier lipoproteins, estradiol, testosterone, and sex hormone binding globulin (SHBG). Comparison of baseline values with values after 3 and 6 months of treatment indicated that both regimens influenced lipid and Androgen Metabolism. There was a statistically significant between-regimen difference in levels of high-density lipoprotein, which were favorably increased with norgestimate triphasic hut reduced with levonorgestrel triphasic. Related data on SHBG showed that plasma levels of this marker of estrogen/Androgen balance were increased significantly more in the norgestimate triphasic group, providing additional evidence of low Androgenicity. Both regimens inhibited follicular ...
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A comparison study of lipid and Androgen Metabolism with triphasic oral contraceptive formulations containing norgestimate or levonorgestrel.
Acta obstetricia et gynecologica Scandinavica. Supplement, 1992Co-Authors: A Janaud, J Rouffy, D Upmalis, M P DainAbstract:The effects of norgestimate triphasic (Ortho Tri-Cyclen, Tri-Ciles) and levonorgestrel triphasic (Triphasi) formulations on lipid and Androgen Metabolism were assessed in a study of 66 healthy women treated through six menstrual cycles. Levels of the following were measured: cholesterol and its subfractions, triglycerides, carrier lipoproteins, estradiol, testosterone, and sex hormone binding globulin (SHBG). Comparison of baseline values with values after 3 and 6 months of treatment indicated that both regimens influenced lipid and Androgen Metabolism. There was a statistically significant between-regimen difference in levels of high-density lipoprotein, which were favorably increased with norgestimate triphasic but reduced with levonorgestrel triphasic. Related data on SHBG showed that plasma levels of this marker of estrogen/Androgen balance were increased significantly more in the norgestimate triphasic group, providing additional evidence of low Androgenicity. Both regimens inhibited follicular growth to the same extent, as evidenced by low mean levels of estradiol in all on-therapy cycles; and both decreased free testosterone. Side effects in both groups were minor and characteristic of those observed with low-dose oral contraceptive agents. The results of the study support the reported safety and positive effects of norgestimate on lipid and Androgen Metabolism, in comparison with a levonorgestrel-containing combined oral contraceptive.
S Palmero - One of the best experts on this subject based on the ideXlab platform.
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Follow-up study on the effects of thyroid hormone administration on Androgen Metabolism of peripubertal rat Sertoli cells
European journal of endocrinology, 1995Co-Authors: M. L. Panno, M Salerno, Marilena Lanzino, G. De Luca, Marcello Maggiolini, Sv Straface, M. Prati, S Palmero, E Bolla, Emilia FugassaAbstract:The inhibitory effect of triiodothyronine (T3) given in early postnatal life on Sertoli cell proliferative activity, leading to their precocious terminal differentiation, has been demonstrated previously. However, data concerning the role of thyroid hormone on Androgen Metabolism of Sertoli cells during the same period are still lacking. In this study we performed a time-course investigation on the effects of T3 treatment on testosterone Metabolism in Sertoli cells isolated from 2-, 3- and 4-weeks-old euthyroid rats. Triiodothyronine (3 micrograms/100 g body wt) was given ip., during the last week prior to sacrifice. Sertoli cells from all animal groups initially were cultured under basal conditions during the first 24 h and subsequently in the presence of testosterone (0.5 mumol/l) with or without T3 (1 nmol/l) for an additional 24 h. This treatment given to 2-week-old animals resulted in reduced testicular growth. As far as Androgen Metabolism is concerned, T3 in vivo and in vitro treatment in 2- and 3-week-old animals induced a lowering of dihydrotestosterone + 3 alpha-diol with an enhancement of the two other 5 alpha-reduced Androgens. The effect was much less pronounced in the oldest group. In both 2- and 3-week-old treated rats a marked reduction of oestradiol was observed, which indicates an inhibition of aromatase activity, mainly in younger animals. This enzyme has been reported to be extremely active in Sertoli cells of rats (of the same strain) between the age of 5 and 20 days, but it decreases rapidly thereafter.(ABSTRACT TRUNCATED AT 250 WORDS)
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Influence of thyroid hormone on Androgen Metabolism in peripuberal rat Sertoli cells
The Journal of endocrinology, 1994Co-Authors: M. L. Panno, M Salerno, Marilena Lanzino, G. De Luca, M. Prati, E Beraldi, Vincenzo Pezzi, M Le Pera, Diego Sisci, S PalmeroAbstract:The aim of the present study was to investigate the influence of thyroid hormones on Androgen Metabolism in Sertoli cells isolated from 3- and 4- week-old rats. Hypothyroidism was induced by the oral administration of 0.025% methimazole (MMI) from birth until the rats were killed at 3 and 4 weeks of age. Half of the MMI-treated animals were injected i.p. with L-triiodothyronine (T3 3 micrograms/100 g body weight) during the last week before death. Sertoli cells from all groups were initially cultured under basal conditions for the first 24 h and subsequently in the presence of testosterone with or without T3 for an additional 24 h. Hypothyroidism was associated with severe impairment of body as well as testicular growth. Indeed, body and testicular weights were similar in 4-week-old hypothyroid animals to those in 3-week-old control rats. Testosterone Metabolism in Sertoli cells isolated from 3- and 4-week-old hypothyroid rats was mainly expressed by the lowering of 5 alpha-dihydrotestosterone + androstane 3 alpha, 17 beta-diol and an enhanced formation of 5 alpha-reduced steroids with poor Androgenic properties (e.g. 5 alpha-androstane, 3, 17 alpha-dione (androstanedione), 5 alpha-androstane, 3-ol-17-one (androsterone)). Treatment of the same group of animals with T3 in vivo and in vitro did not influence the pattern of 5 alpha-reductase steroids substantially. The most striking finding in the Sertoli cells of 3-week-old hypothyroid rats was the dramatic enhancement of oestradiol formation which persisted to a lesser extent 1 week later.(ABSTRACT TRUNCATED AT 250 WORDS)
Takayuki Akimoto - One of the best experts on this subject based on the ideXlab platform.
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DHEA Administration Activates Local Bioactive Androgen Metabolism in Cancellous Site of Tibia of Ovariectomized Rats
Calcified Tissue International, 2011Co-Authors: Jong-hoon Park, Katsuji Aizawa, Motoyuki Iemitsu, Seiji Maeda, Koji Sato, Takayuki Akimoto, Umon Agata, Ikuko Ezawa, Naomi OmiAbstract:It is not known whether local Androgen Metabolism is involved in the mechanisms underlying the dehydroepiandrosterone (DHEA) administration-induced improvement of bone mineral density (BMD) in an estrogen-deficiency state. The aim of the present study was to clarify whether DHEA administration would improve local Androgen Metabolism and BMD in cancellous site of tibia of ovariectomized (OVX) rats. Twenty-two female rats, 6 weeks old, were randomized into three groups: sham-operated rats, OVX control rats, and OVX rats that received DHEA treatment. DHEA was administered intraperitoneally at 20 mg/kg body weight for 8 weeks. The concentrations of free testosterone and dihydrotestosterone (DHT) in cancellous site of tibia did not change as a result of ovariectomy, while the DHT concentration increased following DHEA administration. We revealed that DHEA administration improved the reduction of 17β- and 3β-hydroxysteroid dehydrogenases and clearly reversed the reduction of 5α-reductase types 1 and 2 and Androgen receptor in the cancellous site of tibia of OVX rats. DHEA administration suppressed estrogen deficiency relative to the decrease in the cancellous BMD, which was positively associated with local DHT concentration. These findings indicate that DHEA administration enhances local bioactive Androgen Metabolism in the cancellous tibia of young OVX rats, suggesting that local DHT may play a part in the DHEA administration-induced improvement of cancellous BMD.
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acute exercise activates local bioactive Androgen Metabolism in skeletal muscle
Steroids, 2010Co-Authors: Katsuji Aizawa, Motoyuki Iemitsu, Seiji Maeda, Takeshi Otsuki, Koji Sato, Takashi Ushida, Noboru Mesaki, Takayuki AkimotoAbstract:Androgens, such as testosterone, play important roles in regulation of diverse physiological process of target tissues. Recently, we reported that steroidogenic enzymes exist in skeletal muscle and regulate local production of testosterone in response to exercise. Testosterone is transformed into a bioactive Androgen metabolite, dihydrotestosterone (DHT) by 5α-reductase. However, it is unclear whether exercise stimulates local bioactive Androgen Metabolism in the skeletal muscle in both sexes. In the present study, we examined sex differences in the levels of dehydroepiandrosterone (DHEA), free testosterone, DHT, and steroidogenesis-related enzymes 5α-reductase and Androgen receptor (AR) in rat's skeletal muscle before and after a single bout of exercise. Basal muscular free testosterone and DHT levels were higher in males than females, whereas the levels of DHEA did not differ between the sexes. Muscular DHEA, free testosterone, and DHT levels were increased in both sexes after the exercise. There were no differences of 5α-reductase and AR transcripts and proteins between the sexes, and the expression of 5α-reductase was significantly increased in both sexes after the exercise. Finally, the expression of AR was significantly higher in female rats, but not in males after the exercise. These data suggest that acute exercise enhances the local bioactive Androgen Metabolism in the skeletal muscle of both sexes.
M. L. Panno - One of the best experts on this subject based on the ideXlab platform.
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Follow-up study on the effects of thyroid hormone administration on Androgen Metabolism of peripubertal rat Sertoli cells
European journal of endocrinology, 1995Co-Authors: M. L. Panno, M Salerno, Marilena Lanzino, G. De Luca, Marcello Maggiolini, Sv Straface, M. Prati, S Palmero, E Bolla, Emilia FugassaAbstract:The inhibitory effect of triiodothyronine (T3) given in early postnatal life on Sertoli cell proliferative activity, leading to their precocious terminal differentiation, has been demonstrated previously. However, data concerning the role of thyroid hormone on Androgen Metabolism of Sertoli cells during the same period are still lacking. In this study we performed a time-course investigation on the effects of T3 treatment on testosterone Metabolism in Sertoli cells isolated from 2-, 3- and 4-weeks-old euthyroid rats. Triiodothyronine (3 micrograms/100 g body wt) was given ip., during the last week prior to sacrifice. Sertoli cells from all animal groups initially were cultured under basal conditions during the first 24 h and subsequently in the presence of testosterone (0.5 mumol/l) with or without T3 (1 nmol/l) for an additional 24 h. This treatment given to 2-week-old animals resulted in reduced testicular growth. As far as Androgen Metabolism is concerned, T3 in vivo and in vitro treatment in 2- and 3-week-old animals induced a lowering of dihydrotestosterone + 3 alpha-diol with an enhancement of the two other 5 alpha-reduced Androgens. The effect was much less pronounced in the oldest group. In both 2- and 3-week-old treated rats a marked reduction of oestradiol was observed, which indicates an inhibition of aromatase activity, mainly in younger animals. This enzyme has been reported to be extremely active in Sertoli cells of rats (of the same strain) between the age of 5 and 20 days, but it decreases rapidly thereafter.(ABSTRACT TRUNCATED AT 250 WORDS)
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Influence of thyroid hormone on Androgen Metabolism in peripuberal rat Sertoli cells
The Journal of endocrinology, 1994Co-Authors: M. L. Panno, M Salerno, Marilena Lanzino, G. De Luca, M. Prati, E Beraldi, Vincenzo Pezzi, M Le Pera, Diego Sisci, S PalmeroAbstract:The aim of the present study was to investigate the influence of thyroid hormones on Androgen Metabolism in Sertoli cells isolated from 3- and 4- week-old rats. Hypothyroidism was induced by the oral administration of 0.025% methimazole (MMI) from birth until the rats were killed at 3 and 4 weeks of age. Half of the MMI-treated animals were injected i.p. with L-triiodothyronine (T3 3 micrograms/100 g body weight) during the last week before death. Sertoli cells from all groups were initially cultured under basal conditions for the first 24 h and subsequently in the presence of testosterone with or without T3 for an additional 24 h. Hypothyroidism was associated with severe impairment of body as well as testicular growth. Indeed, body and testicular weights were similar in 4-week-old hypothyroid animals to those in 3-week-old control rats. Testosterone Metabolism in Sertoli cells isolated from 3- and 4-week-old hypothyroid rats was mainly expressed by the lowering of 5 alpha-dihydrotestosterone + androstane 3 alpha, 17 beta-diol and an enhanced formation of 5 alpha-reduced steroids with poor Androgenic properties (e.g. 5 alpha-androstane, 3, 17 alpha-dione (androstanedione), 5 alpha-androstane, 3-ol-17-one (androsterone)). Treatment of the same group of animals with T3 in vivo and in vitro did not influence the pattern of 5 alpha-reductase steroids substantially. The most striking finding in the Sertoli cells of 3-week-old hypothyroid rats was the dramatic enhancement of oestradiol formation which persisted to a lesser extent 1 week later.(ABSTRACT TRUNCATED AT 250 WORDS)
A Janaud - One of the best experts on this subject based on the ideXlab platform.
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A comparison study of lipid and Androgen Metabolism with triphasic oral contraceptive formulations containing norgestimate or levonorgestrel
Acta Obstetricia et Gynecologica Scandinavica, 1992Co-Authors: A Janaud, J Rouffy, D Upmalis, M P DainAbstract:The effects of norgestimate triphasic (Ortho Tri-Cyclen®, Tri-Cilest®) and levonorgestrel triphasic (Triphasil®) formulations on lipid and Androgen Metabolism were assessed in a study of 66 healthy women treated through six menstrual cycles. Levels of the following were measured: cholesterol and its subfractions, triglycerides. carrier lipoproteins, estradiol, testosterone, and sex hormone binding globulin (SHBG). Comparison of baseline values with values after 3 and 6 months of treatment indicated that both regimens influenced lipid and Androgen Metabolism. There was a statistically significant between-regimen difference in levels of high-density lipoprotein, which were favorably increased with norgestimate triphasic hut reduced with levonorgestrel triphasic. Related data on SHBG showed that plasma levels of this marker of estrogen/Androgen balance were increased significantly more in the norgestimate triphasic group, providing additional evidence of low Androgenicity. Both regimens inhibited follicular ...
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A comparison study of lipid and Androgen Metabolism with triphasic oral contraceptive formulations containing norgestimate or levonorgestrel.
Acta obstetricia et gynecologica Scandinavica. Supplement, 1992Co-Authors: A Janaud, J Rouffy, D Upmalis, M P DainAbstract:The effects of norgestimate triphasic (Ortho Tri-Cyclen, Tri-Ciles) and levonorgestrel triphasic (Triphasi) formulations on lipid and Androgen Metabolism were assessed in a study of 66 healthy women treated through six menstrual cycles. Levels of the following were measured: cholesterol and its subfractions, triglycerides, carrier lipoproteins, estradiol, testosterone, and sex hormone binding globulin (SHBG). Comparison of baseline values with values after 3 and 6 months of treatment indicated that both regimens influenced lipid and Androgen Metabolism. There was a statistically significant between-regimen difference in levels of high-density lipoprotein, which were favorably increased with norgestimate triphasic but reduced with levonorgestrel triphasic. Related data on SHBG showed that plasma levels of this marker of estrogen/Androgen balance were increased significantly more in the norgestimate triphasic group, providing additional evidence of low Androgenicity. Both regimens inhibited follicular growth to the same extent, as evidenced by low mean levels of estradiol in all on-therapy cycles; and both decreased free testosterone. Side effects in both groups were minor and characteristic of those observed with low-dose oral contraceptive agents. The results of the study support the reported safety and positive effects of norgestimate on lipid and Androgen Metabolism, in comparison with a levonorgestrel-containing combined oral contraceptive.