scholarly journals Glucocorticoids Amplify Dibutyl Phthalate-Induced Disruption of Testosterone Production and Male Reproductive Development

Endocrinology ◽  
2009 ◽  
Vol 150 (11) ◽  
pp. 5055-5064 ◽  
Author(s):  
Amanda J. Drake ◽  
Sander van den Driesche ◽  
Hayley M. Scott ◽  
Gary R. Hutchison ◽  
Jonathan R. Seckl ◽  
...  
Keyword(s):  
Gene Expression ◽  
Adverse Effects ◽  
Dibutyl Phthalate ◽  
Plasma Testosterone ◽  
High Dose ◽  
Human Populations ◽  
Testis Weight ◽  
Penile Length ◽  
Fetal Testis ◽  
Prostate Weight

Common male reproductive abnormalities including cryptorchidism, hypospadias, and low sperm counts may comprise a testicular dysgenesis syndrome (TDS), resulting from fetal testis dysfunction during a critical developmental period involving reduced androgen production/action. The recent increase in TDS prevalence suggests environmental/lifestyle factors may be etiologically important. The developing fetus is exposed to multimodal challenges, and we hypothesized that exposure to a combination of factors rather than single agents may be important in the pathogenesis of TDS. We experimentally induced fetal testis dysfunction in rats via treatment of pregnant females daily from embryonic day (e) 13.5 to e21.5 with vehicle, 100 or 500 mg/kg · d dibutyl phthalate (DBP), 0.1 mg/kg · d dexamethasone (Dex), or a combination of DBP + Dex. In adulthood, penile length/normality, testis weight/descent, prostate weight, and plasma testosterone levels were measured plus anogenital distance (AGD) as a measure of androgen action within the masculinization programming window. Intratesticular testosterone and steroidogenic enzyme gene expression were measured in fetal testes at e17.5. High-dose DBP reduced fetal intratesticular testosterone and steroidogenic gene expression; induced mild hypospadias (31%) and cryptorchidism (53%); and reduced penile length, AGD, and testis and prostate weight in adulthood. Dex alone had no effect except to reduce birth weight but amplified the adverse effects of 500 mg/kg · d DBP and exacerbated the effects of 100 mg/kg · d DBP. All adverse effects were highly correlated to AGD, emphasizing the etiological importance of the masculinization programming window. These findings suggest that exposure to common environmental chemicals in combination with, for example, maternal stress, may increase the risk of common male reproductive abnormalities, with implications for human populations.

Topical dihydrotestosterone to treat micropenis secondary to partial androgen insensitivity syndrome (PAIS) before, during, and after puberty – a case series

2016 ◽  
Vol 29 (2) ◽  
Author(s):  
David Becker ◽  
Lisa M. Wain ◽  
Yih Harng Chong ◽  
Sonal J. Gosai ◽  
Nina K. Henderson ◽  
...  
Keyword(s):  
Adverse Effects ◽  
Case Series ◽  
Androgen Insensitivity Syndrome ◽  
High Dose ◽  
Long Term Outcomes ◽  
Penile Length ◽  
Androgen Insensitivity ◽  
First Case ◽  
Partial Androgen Insensitivity Syndrome

AbstractX-linked partial androgen insensitivity syndrome (PAIS) causes under-virilization at all stages of development. In two thirds of males, this results in micropenis. Dihydrotestosterone (DHT) is a potent androgen that is critical for male genital development, which when applied topically, has been shown to increase penile length with micropenis of varying etiologies. We present the first case series using topical DHT gel to treat micropenis in 46,XY males with PAIS, before, during, and after puberty.Three related 46,XY males with confirmed p.L712F androgen receptor mutations exhibited varying degrees of micropenis post-surgical correction. They were of pre-pubertal, peri-pubertal and adult ages, respectively. Following baseline clinical and laboratory assessments all completed a 4-month course of daily DHT gel 2.5% (androstanolone) topically to penis (0.3 mg/kg body weight), with monitoring for adverse effects. Primary outcome was change in stretched penile length (SPL) following treatment.Mixed results were obtained following topical DHT therapy. In the pre- and peri- pubertal patients, SPL changed from 2.5 cm to 3.5 cm (+40%), and 3.5 cm to 5.7 cm (+63%), respectively. In the adult patient with 1 year of prior high-dose weekly testosterone therapy, no additional change in SPL was seen. No adverse effects of topical DHT were reported or observed throughout the 4 months of treatment.Topical DHT treatment appears to be a safe and well-tolerated method of virilising micropenis both prior to and during puberty in children with PAIS. Questions remain about long-term outcomes into adulthood, and efficacy in adults with prior lengthy exposure to high-dose testosterone.

scholarly journals Environmentally relevant exposure to dibutyl phthalate disrupts DNA damage repair gene expression in the mouse ovary†

2019 ◽  
Vol 101 (4) ◽  
pp. 854-867 ◽  
Author(s):  
Xiaosong Liu ◽  
Zelieann R Craig
Keyword(s):  
Gene Expression ◽  
Dna Damage ◽  
Dna Methyltransferase ◽  
Dibutyl Phthalate ◽  
Corn Oil ◽  
Excision Repair ◽  
Consumer Products ◽  
Oral Exposure ◽  
High Dose ◽  
Repair Gene

Abstract Phthalates have a history of reproductive toxicity in animal models and associations with adverse reproductive outcomes in women. Human exposure to dibutyl phthalate (DBP) occurs via consumer products (7–10 μg/kg/day) and medications (1–233 μg/kg/day). Most DBP toxicity studies have focused on high supraphysiological exposure levels; thus, very little is known about exposures occurring at environmentally relevant levels. CD-1 female mice (80 days old) were treated with tocopherol-stripped corn oil (vehicle control) or DBP dissolved in oil at environmentally relevant (10 and 100 μg/kg/day) or higher (1000 μg/kg/day) levels for 30 days to evaluate effects on DNA damage response (DDR) pathway genes and folliculogenesis. DBP exposure caused dose-dependent effects on folliculogenesis and gene expression. Specifically, animals exposed to the high dose of DBP had more atretic follicles in their ovaries, while in those treated with environmentally relevant doses, follicle numbers were no different from vehicle-treated controls. DBP exposure significantly reduced the expression of DDR genes including those involved in homologous recombination (Atm, Brca1, Mre11a, Rad50), mismatch repair (Msh3, Msh6), and nucleotide excision repair (Xpc, Pcna) in a dose-specific manner. Interestingly, staining for the DNA damage marker, γH2AX, was similar between treatments. DBP exposure did not result in differential DNA methylation in the Brca1 promoter but significantly reduced transcript levels for the maintenance DNA methyltransferase, Dnmt1, in the ovary. Collectively, these findings show that oral exposure to environmentally relevant levels of DBP for 30 days does not significantly impact folliculogenesis in adult mice but leads to aberrant ovarian expression of DDR genes.

Characterization of the hypothalamo–pituitary–IGF-I axis in rats made obese by overfeeding

1996 ◽  
Vol 148 (2) ◽  
pp. 347-353 ◽  
Author(s):  
L Cattaneo ◽  
V De Gennaro Colonna ◽  
M Zoli ◽  
E E Müller ◽  
D Cocchi
Keyword(s):  
Gene Expression ◽  
Plasma Concentrations ◽  
Male Rats ◽  
Zucker Rats ◽  
Plasma Testosterone ◽  
Acute Administration ◽  
Testis Weight ◽  
Igf I ◽  
Obese Zucker Rats ◽  
Palatable Diet

Abstract Obesity is coupled to several disturbances of the endocrine axes. It has previously been shown that genetically obese Zucker male rats have an impaired secretion of growth hormone (GH), probably originating from a primary reduction of hypothalamic GH-releasing hormone (GHRH) function and resulting in a decrease of GH gene expression and release. We sought to evaluate the somatotropic function in another model of experimental obesity. Normal male Sprague-Dawley rats were fed an energy-rich highly palatable diet for 7 months until they reached body weights overlapping those reported for obese Zucker rats. They were then evaluated for different indices of the hypothalamo–pituitary–somatomedin-C (IGF-I) axis. At the end of the overfeeding period, rats were divided into overtly obese (obese group) and overweight (overweight group) rats according to the degree of overweight and the Obesity Lee Index, while rats fed ad libitum with the standard pellet chow served as controls. Acute administration of a supramaximal dose of GHRH (2 μg/rat i.v.) elicited a significantly (at least P<0·05) lower plasma GH rise in the overweight and obese groups compared with the controls although no difference was seen in the pituitary GH content and gene expression and plasma concentrations of free IGF-I in the two experimental groups vs the controls. In addition, evaluation of hypothalamic GHRH and somatostatin mRNAs (slot-blot hybridization) did not show any significant differences between the three groups. Of the different metabolic indices investigated, plasma glucose and insulin concentrations were significantly (P<0·01) higher in the obese than in the overweight and control groups. A sharp decrease in plasma testosterone levels, together with a reduction in testis weight, was seen in both groups of rats fed the palatable diet compared with the controls. These findings underline the 'peripheral' feature of the hyposomatotropinism of rats chronically fed an energy-rich diet, and may account for the reversibility of the GH impairment in many obese subjects once a normal body weight has been restored. Moreover, the peripherally-driven hyposomatotropinism of these rats is in sharp contrast with the hypothalamic-driven GH secretory impairment of the obese Zucker rats. Journal of Endocrinology (1996) 148, 347–353

Adverse Effects and Laboratory Parameters of High-Dose Olanzapine vs. Clozapine in Treatment-Resistant Schizophrenia

2003 ◽  
Vol 15 (3) ◽  
pp. 181-186 ◽  
Author(s):  
Deanna Kelly ◽  
Robert Conley ◽  
Charles Richardson ◽  
Carol Tamminga ◽  
William Carpenter
Keyword(s):  
Adverse Effects ◽  
High Dose ◽  
Treatment Resistant ◽  
Laboratory Parameters

scholarly journals Combination of subtherapeutic anti-TNF dose with dasatinib restores clinical and molecular arthritogenic profiles better than standard anti-TNF treatment

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Lydia Ntari ◽  
Christoforos Nikolaou ◽  
Ksanthi Kranidioti ◽  
Dimitra Papadopoulou ◽  
Eleni Christodoulou-Vafeiadou ◽  
...  
Keyword(s):  
Gene Expression ◽  
Therapeutic Effect ◽  
Expression Analysis ◽  
Mode Of Action ◽  
Gene Expression Analysis ◽  
Kinase Inhibitors ◽  
High Dose ◽  
Dependent Manner ◽  
Combination Therapies ◽  
Number Of Patients

Abstract Background New medications for Rheumatoid Arthritis (RA) have emerged in the last decades, including Disease Modifying Antirheumatic Drugs (DMARDs) and biologics. However, there is no known cure, since a significant proportion of patients remain or become non-responders to current therapies. The development of new mode-of-action treatment schemes involving combination therapies could prove successful for the treatment of a greater number of RA patients. Methods We investigated the effect of the Tyrosine Kinase inhibitors (TKIs) dasatinib and bosutinib, on the human TNF-dependent Tg197 arthritis mouse model. The inhibitors were administered either as a monotherapy or in combination with a subtherapeutic dose of anti-hTNF biologics and their therapeutic effect was assessed clinically, histopathologically as well as via gene expression analysis and was compared to that of an efficient TNF monotherapy. Results Dasatinib and, to a lesser extent, bosutinib inhibited the production of TNF and proinflammatory chemokines from arthritogenic synovial fibroblasts. Dasatinib, but not bosutinib, also ameliorated significantly and in a dose-dependent manner both the clinical and histopathological signs of Tg197 arthritis. Combination of dasatinib with a subtherapeutic dose of anti-hTNF biologic agents, resulted in a synergistic inhibitory effect abolishing all arthritis symptoms. Gene expression analysis of whole joint tissue of Tg197 mice revealed that the combination of dasatinib with a low subtherapeutic dose of Infliximab most efficiently restores the pathogenic gene expression profile to that of the healthy state compared to either treatment administered as a monotherapy. Conclusion Our findings show that dasatinib exhibits a therapeutic effect in TNF-driven arthritis and can act in synergy with a subtherapeutic anti-hTNF dose to effectively treat the clinical and histopathological signs of the pathology. The combination of dasatinib and anti-hTNF exhibits a distinct mode of action in restoring the arthritogenic gene signature to that of a healthy profile. Potential clinical applications of combination therapies with kinase inhibitors and anti-TNF agents may provide an interesting alternative to high-dose anti-hTNF monotherapy and increase the number of patients responding to treatment.

Gonadal steroids effect similar regulation of gonadotrophin subunit mRNA expression in both male and female rats

1992 ◽  
Vol 132 (1) ◽  
pp. 39-45 ◽  
Author(s):  
A. C. Dalkin ◽  
S. J. Paul ◽  
D. J. Haisenleder ◽  
G. A. Ortolano ◽  
M. Yasin ◽  
...  
Keyword(s):  
Gene Expression ◽  
Steady State ◽  
Gnrh Antagonist ◽  
Gonadal Steroids ◽  
Female Rats ◽  
Plasma Testosterone ◽  
Subunit Gene ◽  
Gnrh Secretion ◽  
Male And Female Rats ◽  
Males And Females

ABSTRACT Gonadal steroids can act both indirectly via gonadotrophin-releasing hormone (GnRH) and directly on the pituitary to regulate gonadotrophin subunit gene expression. Recent studies to assess a possible direct action at the pituitary have shown that testosterone, when given to males in the absence of endogenous GnRH action, selectively increases FSH-β mRNA concentrations. Conversely, in females, oestradiol appears to regulate gonadotrophin subunit mRNAs primarily via GnRH. The present study was designed to determine whether these differing results reflect specific actions of the gonadal steroids themselves or different responses of the pituitary gonadotroph cells in males and females. Rats which had been castrated 7 days earlier were given silicone elastomer implants (s.c.) containing oestradiol (plasma oestradiol 68 ± 4 ng/l) in males or testosterone (plasma testosterone 3·5 ± 0·3 μg/l) in females in the absence or presence of a GnRH antagonist. Seven days later pituitaries were removed and steady-state mRNA concentrations measured by dotblot hybridization. In males, oestradiol reduced LH-β and FSH-β but not α mRNA. The antagonist reduced levels of all three subunit mRNAs in males and the addition of oestradiol had no further effect, suggesting that oestradiol regulates gonadotrophin subunit gene expression in males by suppressing GnRH secretion. In females, testosterone reduced all three subunit mRNAs though FSH-β remained threefold higher than in intact animals. The GnRH antagonist was as effective as testosterone alone and reduced α and LH-β to levels found in intact animals. FSH-β mRNA was partially reduced by antagonist alone in ovariectomized females but the addition of testosterone increased FSH-β twofold versus antagonist alone (as has been observed in males). These findings, together with earlier data, suggest that testosterone increased FSH-β twofold versus antagonist alone (as has been observed in males). These findings, together with earlier data, suggest that testosterone reduces gonadotrophin subunit mRNAs by inhibiting GnRH secretion and also acts directly on the gonadotroph to increase steady-state FSH-β mRNA concentrations in both males and females. Journal of Endocrinology (1992) 132, 39–45

T04-O-05 High dose Testosterone (T) treatment has no adverse effects on the endometrium of Female to Male transsexuals (FtM)

Sexologies ◽  
2008 ◽  
Vol 17 ◽  
pp. S78-S79 ◽  
Author(s):  
A.M. Perrone ◽  
F. Armillotta ◽  
G. Formelli ◽  
P. Casadio ◽  
N.C.M. Salfi ◽  
...  
Keyword(s):  
Adverse Effects ◽  
High Dose
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