Sexual differentiation of the rodent hypothalamus: Hormonal and environmental influences

Negri‐Cesi, P.; Colciago, Alessandra; Pravettoni, A.; Casati, Lavinia; Conti, Luciano; Celotti, F.

doi:10.1016/j.jsbmb.2008.03.003

Cited by 50 publications

(35 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Expression is greater overall for both isozymes in the brainstem than in the forebrain, however, 5 ␣ R2 is found in hypothalamic and hippocampal neurons in adult rodents [Poletti and Martini, 1999]. 5 ␣ R1 has a lower affinity for T and is present in both neurons and glial cells, whereas 5 ␣ R2 has a higher affinity for T and is found primarily in neurons [Negri-Cesi et al, 2008]. Thus, these 2 isozymes may serve somewhat different functions.…”

Section: Introductionmentioning

confidence: 99%

Distribution of Two Isozymes of 5α-Reductase in the Brains of Adult Male and Female Green Anole Lizards

Cohen

Wade²

2010

Brain Behav Evol

View full text Add to dashboard Cite

The 5α-reductase (5αR) enzyme converts testosterone to 5α-dihydrotestosterone. This local metabolism within the brain is important for the full expression of male sexual behavior in many species, including green anole lizards. Two isozymes of 5αR exist and little is known about their specific distributions. We conducted in situ hybridization for both isozymes in intact male and female green anole brains during the breeding (BS) and non-breeding (NBS) seasons. 5αR1 mRNA was only detected in the brainstem, while 5αR2 was expressed in specific areas throughout the brain. As our primary interest was evaluating the potential role of 5αR in forebrain regulation of reproductive behavior, we quantified 5αR2 expression in the preoptic area, amygdala (AMY), and ventromedial hypothalamus (VMH). More 5αR2 cells were detected during the NBS than BS in the AMY, and the density of these cells was greater in females than males. In the VMH, the right side contained more 5αR2 cells than the left, an effect driven by a lateralized increase in the NBS. These data expand understanding of the distribution and potential roles of both isozymes in the adult brain, and differences in expression patterns between mammals and birds suggest that they may have been co-opted for different functions later in evolution.

show abstract

Section: Introductionmentioning

confidence: 99%

Distribution of Two Isozymes of 5α-Reductase in the Brains of Adult Male and Female Green Anole Lizards

Cohen

Wade²

2010

Brain Behav Evol

View full text Add to dashboard Cite

show abstract

“…Given the emergence of environmental substances with androgenic actions in fetal androgenization (10,25), the question arises as to whether developmental androgen excess can program the cardiometabolic features of PCOS. Since developmental testosterone exposure masculinizes the structure and function of the hypothalamus in females (4,33,36,37,47,50), the question also arises as to whether developmental androgen excess programs masculinization of metabolism. Using a mouse model, we reported previously that neonatal androgenization of female mice masculinized the organization of proopiomelanocortin neurons and induced cellular leptin resistance to upregulate the anorexigenic neuropeptide proopiomelanocortin, thereby resulting in failure of leptin to suppress food intake (41).…”

mentioning

confidence: 99%

Developmental androgen excess programs sympathetic tone and adipose tissue dysfunction and predisposes to a cardiometabolic syndrome in female mice

Nohara¹,

Waraich²,

Liu

et al. 2013

American Journal of Physiology-Endocrinology and Metabolism

View full text Add to dashboard Cite

Among women, the polycystic ovarian syndrome (PCOS) is considered a form of metabolic syndrome with reproductive abnormalities. Women with PCOS show increased sympathetic tone, visceral adiposity with enlarged adipocytes, hypoadiponectinemia, insulin resistance, glucose intolerance, increased inactive osteocalcin, and hypertension. Excess fetal exposure to androgens has been hypothesized to play a role in the pathogenesis of PCOS. Previously, we showed that neonatal exposure to the androgen testosterone (NT) programs leptin resistance in adult female mice. Here, we studied the impact of NT on lean and adipose tissues, sympathetic tone in cardiometabolic tissues, and the development of metabolic dysfunction in mice. Neonatally androgenized adult female mice (NTF) displayed masculinization of lean tissues with increased cardiac and skeletal muscle as well as kidney masses. NTF mice showed increased and dysfunctional white adipose tissue with increased sympathetic tone in both visceral and subcutaneous fat as well as increased number of enlarged and insulin-resistant adipocytes that displayed altered expression of developmental genes and hypoadiponectinemia. NTF exhibited dysfunctional brown adipose tissue with increased mass and decreased energy expenditure. They also displayed decreased undercarboxylated and active osteocalcin and were predisposed to obesity during chronic androgen excess. NTF showed increased renal sympathetic tone associated with increased blood pressure, and they developed glucose intolerance and insulin resistance. Thus, developmental exposure to testosterone in female mice programs features of cardiometabolic dysfunction, as can be observed in women with PCOS, including increased sympathetic tone, visceral adiposity, insulin resistance, prediabetes, and hypertension.

show abstract

“…Therefore, to achieve a male-specific brain, it is necessary to activate two independent processes-development of neural circuits enabling expression of male-specific behavior, when activated by testicular hormones (masculinization), and the loss of those able to respond to ovarian hormones (defeminization) during adulthood [33]. The AGD is defined as the distance between the genital papilla and the anus; male rodents have AGDs approximately twice those of females [34] and AGD correlates closely with prenatal exposure to androgens [22].…”

Section: Discussionmentioning

confidence: 99%

Prenatal testosterone supplementation alters puberty onset, aggressive behavior, and partner preference in adult male rats

Cruz

Pereira

2012

J Physiol Sci

View full text Add to dashboard Cite

The objective of this study was to investigate whether prenatal exposure to testosterone (T) could change the body weight (BW), anogenital distance (AGD), anogenital distance index (AGDI), puberty onset, social behavior, fertility, sexual behavior, sexual preference, and T level of male rats in adulthood. To test this hypothesis, pregnant rats received either 1 mg/animal of T propionate diluted in 0.1 ml peanut oil or 0.1 ml peanut oil, as control, on the 17th, 18th and 19th gestational days. No alterations in BW, AGD, AGDI, fertility, and sexual behavior were observed (p > 0.05). Delayed onset of puberty (p < 0.0001), increased aggressive behavior (p > 0.05), altered pattern of sexual preference (p < 0.05), and reduced T plasma level (p < 0.05) were observed for adult male rats exposed prenatally to T. In conclusion, the results showed that prenatal exposure to T was able to alter important aspects of sexual and social behavior although these animals were efficient at producing descendants. In this sense more studies should be carried to evaluated the real impact of this hormonal alteration on critical period of sexual differentiation on humans, because pregnant women exposed to hyperandrogenemia and then potentially exposing their unborn children to elevated androgen levels in the uterus can undergo alteration of normal levels of T during the sexual differentiation period, and, as a consequence, affect the reproductive and behavior patterns of their children in adulthood.

show abstract

Sexual differentiation of the rodent hypothalamus: Hormonal and environmental influences

Cited by 50 publications

References 54 publications

Distribution of Two Isozymes of 5α-Reductase in the Brains of Adult Male and Female Green Anole Lizards

Distribution of Two Isozymes of 5α-Reductase in the Brains of Adult Male and Female Green Anole Lizards

Developmental androgen excess programs sympathetic tone and adipose tissue dysfunction and predisposes to a cardiometabolic syndrome in female mice

Prenatal testosterone supplementation alters puberty onset, aggressive behavior, and partner preference in adult male rats

Contact Info

Product

Resources

About