mRNA Levels of Aromatase, 5α-Reductase Isozymes, and Prostate Cancer-Related Genes in Plucked Hair from Young Men with Androgenic Alopecia.

Androgenic alopecia (AGA) is the most prevalent type of progressive hair loss and has psychological repercussions. Nevertheless, the effectiveness of current pharmacological treatments remains limited, in part because the molecular basis of the disease has not been fully elucidated. Our group previously highlighted the important roles of aromatase and 5α-reductase (5α-R) in alopecia in young women with female pattern hair loss. Additionally, an association has been proposed between AGA and prostate cancer (PCa), suggesting that genes implicated in PCa would also be involved in AGA. A low-invasive, sensitive, and precise method was used to determine mRNA levels of aromatase, 5α-R isozymes, and 84 PCa-related genes in samples of plucked hair from young men with AGA and controls. Samples were obtained with a trichogram from the vertex scalp, and mRNA levels were quantified using real-time RT-PCR. The men with AGA had significantly higher 5α-R2 mRNA levels in comparison to controls; interestingly, some of them also showed markedly elevated mRNA levels of 5α-R1 or 5α-R3 or of both, which may explain the varied response to 5α-R inhibitor treatments. The men with AGA also showed significant changes versus controls in 6 out of the 84 genes implicated in PCa. This study contributes greater knowledge of the molecular bases of AGA, facilitating early selection of the most appropriate pharmacological therapy and opening the way to novel treatments.

Structural insights into choline-O-sulfatase reveal the molecular determinants for ligand binding.

Choline-O-sulfatase (COSe; EC 3.1.6.6) is a member of the alkaline phosphatase (AP) superfamily, and its natural function is to hydrolyze choline-O-sulfate into choline and sulfate. Despite its natural function, the major interest in this enzyme resides in the landmark catalytic/substrate promiscuity of sulfatases, which has led to attention in the biotechnological field due to their potential in protein engineering. In this work, an in-depth structural analysis of wild-type Sinorhizobium (Ensifer) meliloti COSe (SmeCOSe) and its C54S active-site mutant is reported. The binding mode of this AP superfamily member to both products of the reaction (sulfate and choline) and to a substrate-like compound are shown for the first time. The structures further confirm the importance of the C-terminal extension of the enzyme in becoming part of the active site and participating in enzyme activity through dynamic intra-subunit and inter-subunit hydrogen bonds (Asn146A-Asp500B-Asn498B). These residues act as the `gatekeeper' responsible for the open/closed conformations of the enzyme, in addition to assisting in ligand binding through the rearrangement of Leu499 (with a movement of approximately 5 Å). Trp129 and His145 clamp the quaternary ammonium moiety of choline and also connect the catalytic cleft to the C-terminus of an adjacent protomer. The structural information reported here contrasts with the proposed role of conformational dynamics in promoting the enzymatic catalytic proficiency of an enzyme.

Impact of chronic exposure of rats to bisphenol A from perinatal period to adulthood on intraprostatic levels of 5α-reductase isozymes, aromatase, and genes implicated in prostate cancer development.

The synergetic effect of estrogens and androgens is known to play a crucial role in the physiopathology of the prostate gland. Bisphenol A (BPA) is an endocrine disrupting compound that can interfere with endocrine hormone functioning and thereby influence prostate development. The objective of this study was to examine the impact on prostate expression of aromatase, 5α-R isozymes, and prostate cancer-related genes of exposure to low doses of BPA from perinatal period to adulthood. Vehicle or BPA (2.5 µg/kg b.w./day) was administered to gestating Wistar rats from gestational day 12 (GD12) to parturition and then to their male pups from postnatal day 1 (PND1) until euthanization on PND90. Their prostate glands were examined by qRT-PCR, Western blot, PCR array, and morphological study. mRNA and protein levels of 5α-R2 were significantly reduced and mRNA and protein levels of aromatase were significantly increased in BPA-treated animals, which also showed modifications of 8 out of the 84 key genes implicated in the development of prostate cancer. Because BPA interferes with genes involved in intraprostatic androgen and estrogen production and others implicated in prostate cancer, research is warranted into the prostate disease risk associated with chronic low-dose BPA exposure throughout life.

Mediterranean Pine Vole, Microtus duodecimcostatus: A Paradigm of an Opportunistic Breeder.

Most mammalian species of the temperate zones of the Earth reproduce seasonally, existing a non-breeding period in which the gonads of both sexes undergo functional regression. It is widely accepted that photoperiod is the principal environmental cue controlling these seasonal changes, although several exceptions have been described in other mammalian species in which breeding depends on cues such as food or water availability. We studied the circannual reproductive cycle in males of the Mediterranean pine vole, Microtus duodecimcostatus, in the Southeastern Iberian Peninsula. Morphological, hormonal, functional, molecular and transcriptomic analyses were performed. As reported for populations of other species from the same geographic area, male voles captured in wastelands underwent seasonal testis regression in summer whereas, surprisingly, those living either in close poplar plantations or in our animal house reproduced throughout the year, showing that it is the microenvironment of a particular vole subpopulation what determines its reproductive status and that these animals are pure opportunistic, photoperiod-independent breeders. In addition, we show that several molecular pathways, including MAPK, are deregulated and that the testicular "immune privilege" is lost in the inactive testes, providing novel mechanisms linking seasonal testosterone reduction and testis regression.

Divergent Seasonal Reproductive Patterns in Syntopic Populations of Two Murine Species in Southern Spain, Mus spretus and Apodemus sylvaticus.

In most mammals with seasonal reproduction, males undergo testis regression during the non-breeding period. We performed a morphological, hormonal, functional, and molecular study of the testes of sexually inactive males of two species of murine rodents, the wood mouse, Apodemus sylvaticus, and the Algerian mouse, Mus spretus, in syntopic populations of southern Iberian peninsula. Both species reproduce during most of the year, but wood mice stop breeding in the summer whereas Algerian mice do it in winter. Sexually inactive males of A. sylvaticus show complete testis regression with reduced levels of serum testosterone and abnormal distribution of cell-adhesion molecules. Contrarily, inactive males of M. spretus maintain almost normal spermotogenesis despite a significant reduction of androgenic function. The lack of an evident explanation for the divergent seasonal breeding patterns found in southern populations of A. sylvaticus and M. spretus, compared with northern ones, implies that very subtle species/population-specific features and/or non-conspicuous environmental cues probably operate to determine their seasonal breeding pattern. These results also support the notion that multiple models of circannual testis variation are possible for different populations of the same species, showing that the mechanisms controlling seasonal reproduction are in fact very plastic and fast evolving.

Overview on Multienzymatic Cascades for the Production of Non-canonical α-Amino Acids.

The 22 genetically encoded amino acids (AAs) present in proteins (the 20 standard AAs together with selenocysteine and pyrrolysine), are commonly referred as proteinogenic AAs in the literature due to their appearance in ribosome-synthetized polypeptides. Beyond the borders of this key set of compounds, the rest of AAs are generally named imprecisely as non-proteinogenic AAs, even when they can also appear in polypeptide chains as a result of post-transductional machinery. Besides their importance as metabolites in life, many of D-α- and L-α-"non-canonical" amino acids (NcAAs) are of interest in the biotechnological and biomedical fields. They have found numerous applications in the discovery of new medicines and antibiotics, drug synthesis, cosmetic, and nutritional compounds, or in the improvement of protein and peptide pharmaceuticals. In addition to the numerous studies dealing with the asymmetric synthesis of NcAAs, many different enzymatic pathways have been reported in the literature allowing for the biosynthesis of NcAAs. Due to the huge heterogeneity of this group of molecules, this review is devoted to provide an overview on different established multienzymatic cascades for the production of non-canonical D-α- and L-α-AAs, supplying neophyte and experienced professionals in this field with different illustrative examples in the literature. Whereas the discovery of new or newly designed enzymes is of great interest, dusting off previous enzymatic methodologies by a "back and to the future" strategy might accelerate the implementation of new or improved multienzymatic cascades.

Effects of adult male rat feminization treatments on brain morphology and metabolomic profile.

Body feminization, as part of gender affirmation process of transgender women, decreases the volume of their cortical and subcortical brain structures. In this work, we implement a rat model of adult male feminization which reproduces the results in the human brain and allows for the longitudinal investigation of the underlying structural and metabolic determinants in the brain of adult male rats undergoing feminization treatments. Structural MRI and Diffusion Tensor Imaging (DTI) were used to non-invasively monitor in vivo cortical brain volume and white matter microstructure over 30 days in adult male rats receiving estradiol (E2), estradiol plus cyproterone acetate (CA), an androgen receptor blocker and antigonadotropic agent (E2 + CA), or vehicle (control). Ex vivo cerebral metabolic profiles were assessed by 1H High Resolution Magic Angle Spinning NMR (1H HRMAS) at the end of the treatments in samples from brain regions dissected after focused microwave fixation (5 kW). We found that; a) Groups receiving E2 and E2 + CA showed a generalized bilateral decrease in cortical volume; b) the E2 + CA and, to a lesser extent, the E2 groups maintained fractional anisotropy values over the experiment while these values decreased in the control group; c) E2 treatment produced increases in the relative concentration of brain metabolites, including glutamate and glutamine and d) the glutamine relative concentration and fractional anisotropy were negatively correlated with total cortical volume. These results reveal, for the first time to our knowledge, that the volumetric decreases observed in trans women under cross-sex hormone treatment can be reproduced in a rat model. Estrogens are more potent drivers of brain changes in male rats than anti-androgen treatment.

Effects of perinatal exposure to bisphenol A on the intraprostatic levels of aromatase and 5α-reductase isozymes in juvenile rats.

The impact of bisphenol A (BPA) on the prostate gland has taken center stage, with a special focus placed on understanding how BPA affects prostate physiopathology. In this study, we evaluated the ability of lower doses of BPA to induce alterations in 5α-R isozymes and aromatase, in the prostate of juvenile rats exposed during developmental stage. Gestating Wistar rats were treated s.c with either vehicle or BPA (2.4 and 10 µg/kg b.w./day) from gestational day 12 to parturition. Then, male pups were s.c treated from postnatal day 1 through day 21, when they were euthanized and qRT-PCR, western blot and hormone levels determination were performed. We found that BPA at dose of 2.4 and 10 µg/kg b.w./day significantly decreased the mRNA and protein levels of 5α-R2. However, neither 5α-R1 nor 5α-R3 was affected by this exposure. BPA at dose of 10 µg/kg b.w./day significantly increased the mRNA and protein levels of aromatase. BPA also decreased plasma levels of both testosterone and dihydrotestosterone and increased estradiol. These data lend support that low-dose BPA during fetal and neonatal prostate development interfere with in situ estrogen and androgen production in the prostate gland of juvenile rats through the enzymes aromatase and 5α-Reductase.

Effects of Adult Female Rat Androgenization on Brain Morphology and Metabolomic Profile.

Androgenization in adult natal women, as in transsexual men (TM), affects brain cortical thickness and the volume of subcortical structures. In order to understand the mechanism underlying these changes we have developed an adult female rat model of androgenization. Magnetic resonance imaging and spectroscopy were used to monitor brain volume changes, white matter microstructure and ex vivo metabolic profiles over 32 days in androgenized and control subjects. Supraphysiological doses of testosterone prevents aging decrease of fractional anisotropy values, decreased general cortical volume and the relative concentrations of glutamine (Gln) and myo-Inositol (mI). An increase in the N-acetylaspartate (NAA)/mI ratio was detected d. Since mI and Gln are astrocyte markers and osmolytes, we suspect that the anabolic effects of testosterone change astrocyte osmolarity so as to extrude Mi and Gln from these cells in order to maintain osmotic homeostasis. This mechanism could explain the brain changes observed in TM and other individuals receiving androgenic anabolic steroids.

Identification of dopamine- and serotonin-related genes modulated by bisphenol A in the prefrontal cortex of male rats.

There is concern that exposure of embryos and/or infants to bisphenol A (BPA) may lead to neurological and behavioral disorders with unknown prefrontal cortex (PFC) involvement. Critical PFC functions are modulated by dopamine (DA) and serotonin (5-HT) systems, whose alterations have been associated with psychopathologies that may appear in youth and/or adulthood. This study aims to determine in the PFC of male rats exposed to a low dose of BPA (10µgkg(-1)d(-1)) from gestational day 12 (GD12) to postnatal day 21 (PND21): (i) DA- and 5-HT-related genes modulated by BPA at the juvenile stage (PND21); (ii) reversible and irreversible transcriptional effects; (iii) long-term consequences (effects in adult rats, PND90). In juvenile rats, BPA altered significantly the transcription of 12 out of the 84 genes analyzed using PCR-array techniques. Interestingly, transcript levels of the neurotrophic factor Gdnf were decrease by BPA in both juvenile and adult rats. At adulthood, disruptions in genes encoding rate-limiting enzymes for DA and 5-HT synthesis emerged. Overall, the results indicate that early-life exposure to BPA has consequences on DA and 5-HT systems in both juvenile- and adult-life stages. Additionally, we reveal molecular targets that could provide the foundation for future BPA neurotoxicity studies.

Bisphenol A, bisphenol F and bisphenol S affect differently 5α-reductase expression and dopamine-serotonin systems in the prefrontal cortex of juvenile female rats.

BACKGROUND: Early-life exposure to the endocrine disruptor bisphenol A (BPA) affects brain function and behavior, which might be attributed to its interference with hormonal steroid signaling and/or neurotransmitter systems. Alternatively, the use of structural analogs of BPA, mainly bisphenol F (BPF) and bisphenol S (BPS), has increased recently. However, limited in vivo toxicity data exist. OBJECTIVES: We investigated the effects of BPA, BPF and BPS on 5α-reductase (5α-R), a key enzyme involved in neurosteroidogenesis, as well as on dopamine (DA)- and serotonin (5-HT)-related genes, in the prefrontal cortex (PFC) of juvenile female rats. METHODS: Gestating Wistar rats were treated with either vehicle or 10 µg/kg/day of BPA, BPF or BPS from gestational day 12 to parturition. Then, female pups were exposed from postnatal day 1 through day 21 (PND21), when they were euthanized and RT-PCR, western blot and quantitative PCR-array experiments were performed. RESULTS: BPA decreased 5α-R2 and 5α-R3 mRNA and protein levels, while both BPF and BPS decreased 5α-R3 mRNA levels in PFC at PND21. Further, BPA, BPF and BPS significantly altered, respectively, the transcription of 25, 56 and 24 genes out of the 84 DA and 5-HT-related genes assayed. Of particular interest was the strong induction by all these bisphenols of Cyp2d4, implicated in corticosteroids synthesis. CONCLUSIONS: Our results demonstrate for the first time that BPA, BPF and BPS differentially affect 5α-R and genes related to DA/5-HT systems in the female PFC. In vivo evidence of the potential adverse effects of BPF and BPS in the brain of mammals is provided in this work, raising questions about the safety of these chemicals as substitutes for BPA.

The testis of greater white-toothed shrew Crocidura russula in Southern European populations: a case of adaptive lack of seasonal involution?

Males of all seasonal breeding mammals undergo circannual periods of testis involution resulting in almost complete ablation of the germinative epithelium. We performed a morphometric, histological, hormonal, and gene-expression study of the testes from winter and summer males of the greater white-toothed shrew, Crocidura russula, in populations of the southeastern Iberian Peninsula. Unexpectedly, we found no significant differences between the two study groups. Surprisingly, female data confirmed a non-breeding period in the summer, evidencing that males retain full testis function even when most females are not receptive. This situation, which has not been described before, does not occur in northern populations of the same species where, in addition, the reproductive cycle is inverted with respect to those in the south, as the non-breeding period occurs in winter instead in summer. Considering that the non-reproductive period shortens at lower latitude locations, we hypothesize that in southern populations the non-breeding period is short enough to make testis regression inefficient in terms of energy savings, because: (1) testes of C. russula are very small, a condition derived from their monogamy that implies low investment in spermatogenesis; and (2) the spermatogenic cycle of this species is slow and long. The inverted seasonal breeding cycle and the lack of seasonal testis regression described here are new adaptive processes that deserve further research, and provide evidence that the genetic and hormonal mechanisms controlling reproduction timing in mammals are more plastic and versatile than initially suspected.

Effects of different ethanol-administration regimes on mRNA and protein levels of steroid 5α-reductase isozymes in prefrontal cortex of adolescent male rats.

RATIONALE: Underage drinking is a leading public health problem in developed countries. An increasing proportion of adolescents consume alcoholic beverages every weekend. Increased anxiety, irritability, and depression among adolescents may induce them to seek for the anxiolytic and rewarding properties of alcohol. Allopregnanolone (AlloP) shares rewarding effects of ethanol and modulates ethanol intake. The rate-limiting enzyme in the biosynthesis of AlloP is steroid 5α-reductase (5α-R), which is expressed as three isozymes, 5α-R1, 5α-R2, and 5α-R3. OBJECTIVE: The objective of this study was to quantify the expression levels of 5α-R isozymes in prefrontal cortex (PFC) of adolescent male rats after three different regimes of ethanol administration. METHODS: Adolescent male Wistar rats were administered with ethanol (4 g/kg) or saline intraperitoneally for 1 day (acute), for 7 days (chronic), or every 72 h for 14 days (chronic intermittent). Messenger (m)RNA and protein levels of 5α-R isozymes were measured by quantitative RT-PCR and Western blot, respectively. RESULTS: Ethanol significantly increased mRNA and protein levels of 5α-R1, 5α-R2, and 5α-R3 in the three different regimes of ethanol administration, being higher in the chronic intermittent regime in comparison with the others. CONCLUSIONS: The expression of the AlloP-biosynthetic enzyme 5α-Rs increases in the prefrontal cortex of adolescent male rats under acute, chronic, and chronic intermittent regime of ethanol administration. The latter is very interesting because it mimics the teenage drinking behavior.

Effects of adult exposure to bisphenol a on genes involved in the physiopathology of rat prefrontal cortex.

Several neurological and behavioral dysfunctions have been reported in animals exposed to bisphenol A (BPA). However, little is known about the impact of adult exposure to BPA on brain physiopathology. Here, we focused on prefrontal cortex (PFC) of rats, because it is an important area for cognitive control, complex behaviors and is altered in many psychopathologies. Gamma-aminobutyric acid (GABA) and serotonin (5-HT) systems are essential for PFC function. Therefore, we examined the effects of adult exposure to BPA on 5α-Reductase (5α-R) and cytochrome P450 aromatase (P450arom), enzymes that synthesize GABAA receptor modulators, and tryptophan hydroxylase (Tph), the rate-limiting enzyme in 5-HT biosynthesis. To gain better understanding of BPA's action in the adult PFC, 84 genes involved in neurotoxicity were also analysed. Adult male and female rats were subcutaneously injected for 4 days with 50 µg/kg/day, the current reference safe dose for BPA. mRNA and protein levels of 5α-R, P450arom and Tph were quantified by real-time RT-PCR and Western blot. Genes linked to neurotoxicity were analyzed by PCR-Array technology. Adult exposure to BPA increased both P450arom and Tph2 expression in PFC of male and female, but decreased 5α-R1 expression in female. Moreover, we identified 17 genes related to PFC functions such as synaptic plasticity and memory, as potential targets of BPA. Our results provided new insights on the molecular mechanisms underlying BPA action in the physiopathology of PFC, but also raise the question about the safety of short-term exposure to it in the adulthood.

Bisphenol A modifies the regulation exerted by testosterone on 5 α -reductase isozymes in ventral prostate of adult rats.

The development, growth, and function of the prostate gland depend on androgen stimulation. The primary androgen in prostate is 5α-dihydrotestosterone (DHT) which is synthesized from circulating testosterone (T) through the action of 5α-reductase (5α-R). Although 5α-R occurs as five isozymes, only 5α-R1 and 5α-R2 are physiologically involved in steroidogenesis. The endocrine disruptor bisphenol A (BPA) alters sexual organs, including the prostate. Our previous findings indicated that BPA decreased the expression of 5α-R1 and 5α-R2 in rat prostate but also circulating T. Thus, it is unclear whether BPA exerts this effect on 5α-R isozymes by reducing circulating T or by any other mechanism. In this study, we examine the effects of short-term exposure to BPA at doses below 25 µg/Kg/d and above 300 µg/Kg/d of the TDI on mRNA levels of 5α-R1 and 5α-R2 in prostate of adult castrated rats supplemented with T to achieve constant circulating T levels. mRNA levels were measured by absolute quantitative RT-PCR, T levels by RIA, and DHT levels by ELISA. Our results indicated that in castrated rats treated with T BPA at the two doses studied significantly decreased the mRNA levels of both 5α-R isozymes in a dose-dependent manner without modifications in circulating T.

Identification of live germ-cell desquamation as a major mechanism of seasonal testis regression in mammals: a study in the Iberian mole (Talpa occidentalis).

In males of seasonally breeding species, testes undergo a severe involution at the end of the breeding season, with a major volume decrease due to massive germ-cell depletion associated with photoperiod-dependent reduced levels of testosterone and gonadotropins. Although it has been repeatedly suggested that apoptosis is the principal effector of testicular regression in vertebrates, recent studies do not support this hypothesis in some mammals. The purpose of our work is to discover alternative mechanisms of testis regression in these species. In this paper, we have performed a morphological, hormonal, ultrastructural, molecular, and functional study of the mechanism of testicular regression and the role that cell junctions play in the cell-content dynamics of the testis of the Iberian mole, Talpa occidentalis, throughout the seasonal breeding cycle. Desquamation of live, nonapoptotic germ cells has been identified here as a new mechanism for seasonal testis involution in mammals, indicating that testis regression is regulated by modulating the expression and distribution of the cell-adhesion molecules in the seminiferous epithelium. During this process, which is mediated by low intratesticular testosterone levels, Sertoli cells lose their nursing and supporting function, as well as the impermeability of the blood-testis barrier. Our results contradict the current paradigm that apoptosis is the major testis regression effector in vertebrates, as it is clearly not true in all mammals. The new testis regression mechanism described here for the mole could then be generalized to other mammalian species. Available data from some previously studied mammals should be reevaluated.

Effects of metoclopramide on mRNA levels of steroid 5á-reductase isozymes in prostate of adult rats

The rising incidence of prostate cancer and benign prostatic hypertrophy in the Western world is a cause of increasing public health concern. The most active androgen in the prostate is 5á-dihydrotestosterone obtained from testosterone (T) by the enzyme 5á-reductase (5á-R), expressed in the prostate as two isozymes, 5á-R1 and 5á-R2. These isozymes are involved in the growth and development of normal prostate and in the onset and progression of prostate disease. Besides androgens, prolactin (PRL) may also play a role, although it is not clear whether its effects on the prostate are in synergism with or independent of those of androgens. We previously demonstrated that sulpiride, an inductor of hyperprolactinemia, increased mRNA levels of 5á-R isozymes in prostate of adult rat. We hypothesized a possible interrelationship between PRL levels and 5á-R, although the effects of sulpiride per se cannot be ruled out. In the present study, one-step quantitative reverse transcription polymerase chain reaction coupled with laser-induced fluorescence capillary electrophoresis was used to quantify mRNA levels of both 5á-R isozymes in prostate of adult rat after administration of metoclopramide (MTC), another inductor of PRL secretion. With the administration regimens studied, MTC produced an increase in prostate weight and mRNA levels of 5á-R1 and 5á-R2 in adult rats. Given our finding that MTC per se or MTC-induced hyperprolactinemia modifies prostate disease-related parameters in animals with reduced plasma T levels, further investigation is warranted into the possibility that MTC use by aging males may increase their risk of prostate disease (AU)

Bisphenol A exposure during adulthood alters expression of aromatase and 5α-reductase isozymes in rat prostate.

The high incidence of prostate cancer (PCa) and benign prostatic hypertrophy (BPH) in elderly men is a cause of increasing public health concern. In recent years, various environmental endocrine disruptors, such as bisphenol A (BPA), have been shown to disrupt sexual organs, including the prostate gland. However, the mechanisms underlying these effects remain unclear. Because androgens and estrogens are important factors in prostate physiopathology, our objective was to examine in rat ventral prostate the effects of adult exposure to BPA on 5α-Reductase isozymes (5α-R types 1, 2, and 3) and aromatase, key enzymes in the biosynthesis of dihydrotestosterone and estradiol, respectively. Adult rats were subcutaneously injected for four days with BPA (25, 50, 300, or 600 µg/Kg/d) dissolved in vehicle. Quantitative RT-PCR, western blot and immunohistochemical analyses showed lower mRNA and protein levels of 5α-R1 and 5α-R2 in BPA-treated groups versus controls but higher mRNA levels of 5α-R3, recently proposed as a biomarker of malignancy. However, BPA treatment augmented mRNA and protein levels of aromatase, whose increase has been described in prostate diseases. BPA-treated rats also evidenced a higher plasma estradiol/testosterone ratio, which is associated with prostate disease. Our results may offer new insights into the role of BPA in the development of prostate disease and may be of great value for studying the prostate disease risk associated with exposure to BPA in adulthood.

Effects of metoclopramide on mRNA levels of steroid 5α-reductase isozymes in prostate of adult rats.

The rising incidence of prostate cancer and benign prostatic hypertrophy in the Western world is a cause of increasing public health concern. The most active androgen in the prostate is 5α-dihydrotestosterone obtained from testosterone (T) by the enzyme 5α-reductase (5α-R), expressed in the prostate as two isozymes, 5α-R1 and 5α-R2. These isozymes are involved in the growth and development of normal prostate and in the onset and progression of prostate disease. Besides androgens, prolactin (PRL) may also play a role, although it is not clear whether its effects on the prostate are in synergism with or independent of those of androgens. We previously demonstrated that sulpiride, an inductor of hyperprolactinemia, increased mRNA levels of 5α-R isozymes in prostate of adult rat. We hypothesized a possible interrelationship between PRL levels and 5α-R, although the effects of sulpiride per se cannot be ruled out. In the present study, one-step quantitative reverse transcription polymerase chain reaction coupled with laser-induced fluorescence capillary electrophoresis was used to quantify mRNA levels of both 5α-R isozymes in prostate of adult rat after administration of metoclopramide (MTC), another inductor of PRL secretion. With the administration regimens studied, MTC produced an increase in prostate weight and mRNA levels of 5α-R1 and 5α-R2 in adult rats. Given our finding that MTC per se or MTC-induced hyperprolactinemia modifies prostate disease-related parameters in animals with reduced plasma T levels, further investigation is warranted into the possibility that MTC use by aging males may increase their risk of prostate disease.