Maternal exposure to ibuprofen can affect the programming of the hypothalamus of the male offspring

Effects of pharmaceutical and personal care products on pubertal development: Evidence from human and animal studies

Pharmaceutical and personal care products (PPCPs) include a wide range of drugs, personal care products and household chemicals that are produced and used in significant quantities. The safety of PPCPs has become a growing concern in recent decades due to their ubiquitous presence in the environment and potential risks to human health. PPCPs have been detected in various human biological samples, including those from children and adolescents, at concentrations ranging from several ng/L to several thousand μg/L. Epidemiological studies have shown associations between exposure to PPCPs and changes in the timing of puberty in children and adolescents. Animal studies have shown that exposure to PPCPs results in advanced or delayed pubertal onset. Mechanisms by which PPCPs regulate pubertal development include alteration of the hypothalamic kisspeptin and GnRH networks, disruption of steroid hormones, and modulation of metabolic function and epigenetics. Gaps in knowledge and further research needs include the assessment of environmental exposure to pharmaceuticals in children and adolescents, low-dose and long-term effects of exposure to PPCPs, and the modes of action of PPCPs on pubertal development. In summary, this comprehensive review examines the potential effects of exposure to PPCPs on pubertal development based on evidence from human and animal studies.

A low dose of benzo(a)pyrene during prepuberty in male rats generated immediate oxidative stress in the testes and compromised steroidogenic enzymes/proteins

The prepubertal period is crucial for sexual development and any alterations can interfere with the reproductive system in adulthood. The aim of this study was to evaluate how Benzo(a)pyrene (BaP) can affect the testes during the prepubertal period. Juvenile male Wistar rats were divided into a control (corn oil + DMSO) and a BaP-group (0.1 μg/kg/day), exposed to BaP for 31 days (gavage), and all parameters were evaluated on postnatal day (PND) 54. Leukocyte counts were decreased. Histological analyses of the testes revealed that height and seminiferous tubules diameters (STDs) were reduced, tubular dynamics were altered, and Leydig cell atrophy was evident in the BaP-group. The testosterone concentration was decreased while FSH levels increased within the BaP-exposed group. Steroidogenic enzymes in the testes were decreased, but steroidogenic acute regulatory protein was not altered. The expression of gstp1 and ckit enzymes was decreased. Reduced glutathione (GSH) and superoxide dismutase (SOD) were increased, whereas malondialdehyde (MDA) was decreased in the testes. In conclusion, BaP or its metabolites causes low systemic toxicity; however, it adversely influences testicular function by disrupting the hormonal axis, unbalancing testicular antioxidative, and blocking the action of the steroidogenic mechanisms.

Can exposure to lisdexamfetamine dimesylate from juvenile period to peripubertal compromise male reproductive parameters in adult rats?

Lisdexamfetamine (LDX) is a d-amphetamine prodrug used to treat attention deficit and hyperactivity disorder, a common neurodevelopmental disorder in children and adolescents. Due to its action mediated by elevated levels of catecholamines, mainly dopamine and noradrenaline, which influence hormonal regulation and directly affect the gonads, this drug may potentially disrupt reproductive performance. This study evaluated the effects of exposure to LDX from the juvenile to peripubertal period (critical stages of development) on systemic and reproductive toxicity parameters in male rats. Male Wistar rats (23 days old) were treated with 0; 5.2; 8.6 or 12.1 mg/kg/day of LDX from post-natal day (PND) 23 to 53, by gavage. LDX treatment led to reduced daily food and water consumption, as well as a decrease in social behaviors. The day of preputial separation remained unaltered, although the treated animals exhibited reduced weight. At PND 54, the treated animals presented signs of systemic toxicity, evidenced by a reduction in body weight gain, increase in the relative weight of the liver, spleen, and seminal gland, reduction in erythrocyte and leukocyte counts, reduced total protein levels, and disruptions in oxidative parameters. In adulthood, there was an increase in immobile sperm, reduced sperm count, morphometric changes in the testis, and altered oxidative parameters, without compromising male sexual behavior and fertility. These findings showed that LDX-treatment during the juvenile and peripubertal periods induced immediate systemic toxicity and adversely influenced reproductive function in adult life, indicating that caution is necessary when prescribing this drug during the peripubertal phase.

A mixture of glyphosate and 2,4-D herbicides enhances the deleterious reproductive outcomes induced by Western diet in obese male mice

The consumption of Western diet (WD) - enriched in fats and sugars - is associated with overweight, obesity and male reproductive disorders. In addition to WD intake, crops and dairy products display residues of herbicides, including glyphosate and 2,4-D that are widely applied worldwide. The concomitant exposure to WD and herbicides - mimicking contemporary scenarios - is not fully investigated. Thus, we evaluated the effects of glyphosate and 2,4-D, alone or in mixture, on WD-induced alterations in the male genital system. Male C57BL6J mice were submitted to WD (chow containing 20% lard, 0.2% cholesterol, 20% sucrose, and high sugar solution with 23.1 and 18.9 g/L of D-fructose and D-glucose) for 6 months. Concomitantly to WD, the animals received glyphosate (0.05, 5, or 50 mg/kg/day), 2,4-D (0.02, 2 or 20 mg/kg/day) or their mixture (0, 05 + 0.02, 5 + 2, or 50 + 20 mg/kg/day) by intragastrical administration (5×/week). Doses were based on Acceptable Daily Intake (ADIs) or No Observed Adverse Effect Level (NOAEL) values. Herbicide exposure did not alter the WD-induced obesity, hypercholesterolemia and hyperglycemia. WD induced sperm cell abnormalities, reduced the number, volume and area of Leydig cells, enhanced the frequency of epididymal abnormalities, decreased the proliferation in both germinal and epididymal epithelia, and reduced the number of androgen receptor (AR) positive epididymal cells. Remarkably, the herbicide mixtures promoted such WD-induced effects: increased the frequency of sperm cell and epididymal abnormalities (absence of sperm, cytoplasmic vacuoles, and clear cell hypertrophy) (5 + 2 and 50 + 20 doses); decreased Leydig cell nuclei volume and area (5 + 2 and 50 + 20 doses), reduced epididymal cell proliferation (all mixtures), and AR expression (50 + 20 dose). In addition, herbicide mixtures reduced serum testosterone levels (5 + 2 and 50 + 20 doses). Our findings indicate that the mixture of glyphosate and 2,4-D herbicides, mimicking environmentally relevant scenarios, promotes WD-induced changes in the male genital system.

Insights from the maternal lineage of the F2 generation after exposure to an environmentally relevant dose of benzo(a)pyrene in the male rats of F0 generation

Benzo(a)pyrene (BaP) is a substance with the potential to induce endocrine disruption in the F0 generation and cause adverse multigenerational effects (F1 generation) for reproductive parameters in rats. The objective of this study was to investigate the occurrence of transgenerational inheritance in the reproductive aspects of male and female rats belonging to the F2 generation (MF2). This investigation was conducted following the exposure of male rats from the F0 generation to BaP to assess potential effects on subsequent generation from the maternal lineage (F1). For that, juvenile male Wistar rats (F0) were orally exposed to BaP (0.1 µg/kg/day) for 31 consecutive days. In adulthood, they were mated with untreated females to obtain female offspring (F1), which later produced the MF2. In the MF2 generation, both males and females exhibited increased body weight on postnatal day (PND) 1. In MF2 males, we observed delayed preputial separation, altered pup weight, reduced levels of follicle-stimulating hormone (FSH), increased intratesticular testosterone levels, decreased type A sperm, epididymal disturbances, reduced 5 α-reductase activity, increased testicular proliferation, and alterations in testicular antioxidant enzymes. In MF2 females, we noted morphological uterine enlargement, reduced sexual activity, and decreased progesterone levels. The findings suggest that the alterations observed in both MF2 males and females can be attributed to modifications in the sperm from F0 generation, which were subsequently transmitted to F1 females and MF2 generation due to BaP exposure.

Lactational exposure to venlafaxine provokes late repercussions on reproductive parameters in male rat offspring

Exposure to selective serotonin reuptake inhibitors can affect hormone-dependent processes, such as the brain sexual differentiation. Because the use of these antidepressants cause concern during lactation, we evaluated the possible effects of venlafaxine on lactational exposure and its late repercussions on reproductive parameters in male rats. Lactating rats were exposed to venlafaxine (3.85, 7.7, or 15.4 mg/kg/body weight; gavage), from lactational day 1 to 20. Venlafaxine and O-desmethylvenlafaxine residues were found in all milk samples of dams treated, demonstrating the lactational transfer of this antidepressant to the offspring. Although the maternal behavior was normal, the dams presented an increase in urea and uric acid levels in the groups treated with 7.7 and 15.4, respectively, as well as a spleen weight increased in the 3.85 and 15.4 groups. The male offspring showed a decrease in play behavior parameters in the intermediate dose group. Sperm analysis indicated a reduction in sperm motility in all treated groups. The androgen receptor expression in the hypothalamus was decreased in the highest dose group, although the sexual behavior had not been affected. In conclusion, venlafaxine was transferred through breast milk and promoted changes in play behavior, sperm quality, and hypothalamic androgen receptor (AR) content, which may indicate an incomplete masculinization of the brain of male offspring.

Safety evaluation of ondansetron after gestational exposure on male reproductive parameters in rats

Ondansetron is a 5HT3 receptor antagonist widely used to treat hyperemesis gravidarum, although its safety is still questionable. Since 5HT3 receptors, which are the target of this drug, can interfere with brain development through changes in neurotransmitter levels, this study evaluated whether the prenatal exposure to this drug could compromise reproductive and behavioral parameters in male offspring. Pregnant rats were treated with ondansetron (1.7 and 2.5 mg/kg/body weight; gavage), from gestational day 1-21. No exposure-related changes in clinical signs, body weight, food consumption, pregnancy length, and necropsy findings were observed in dams. Ondansetron exposure did not alter the anogenital distance or age of preputial separation in male offspring. Similarly, males exposed to therapeutic doses of ondansetron did not exhibit changes in play behavior. In adulthood, there were no changes in sperm parameters, as well as in testosterone level, sexual behavior and fertility. Furthermore, ondansetron did not interfere with testicular and epididymal histology, and with androgen receptor expression in hypothalamus. In conclusion, prenatal exposure to ondansetron did not cause maternal toxicity, as well as did not interfere with reproductive parameters of male offspring, indicating its safety after gestational exposure in rats.

Using Experimental Models to Decipher the Effects of Acetaminophen and NSAIDs on Reproductive Development and Health

Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin (acetylsalicylic acid), diclofenac and ibuprofen (IBU), and analgesic drugs, such as acetaminophen (APAP, or paracetamol), are widely used to treat inflammation and pain. APAP and IBU are over-the-counter drugs and are among the most commonly taken drugs in the first trimester of pregnancy, even in combination. Furthermore, these drugs and their metabolites are released in the environment, and can be frequently detected in wastewater, surface water, and importantly in drinking water. Although their environmental concentrations are much lower than the therapeutics doses, this suggests an uncontrolled low-dose exposure of the general population, including pregnant women and young children, two particularly at risk populations. Epidemiological studies show that exposure to these molecules in the first and second trimester of gestation can favor genital malformations in new-born boys. To investigate the cellular, molecular and mechanistic effects of exposure to these molecules, ex vivo studies with human or rodent gonadal explants and in vivo experiments in rodents have been performed in the past years. This review recapitulates recent data obtained in rodent models after in utero or postnatal exposure to these drugs. The first part of this review discusses the mechanisms by which NSAIDs and analgesics may impair gonadal development and maturation, puberty development, sex hormone production, maturation and function of adult organs, and ultimately fertility in the exposed animals and their offspring. Like other endocrine disruptors, NSAIDs and APAP interfere with endocrine gland function and may have inter/transgenerational adverse effects. Particularly, they may target germ cells, resulting in reduced quality of male and female gametes, and decreased fertility of exposed individuals and their descendants. Then, this review discusses the effects of exposure to a single drug (APAP, aspirin, or IBU) or to combinations of drugs during early embryogenesis, and the consequences on postnatal gonadal development and adult reproductive health. Altogether, these data may increase medical and public awareness about these reproductive health concerns, particularly in women of childbearing age, pregnant women, and parents of young children.

Eicosanoid Biosynthesis in Male Reproductive Development: Effects of Perinatal Exposure to NSAIDs and Analgesic Drugs

Increasing rates of infertility associated with declining sperm counts and quality, as well as increasing rates of testicular cancer are contemporary issues in the United States and abroad. These conditions are part of the Testicular Dysgenesis Syndrome, which includes a variety of male reproductive disorders hypothesized to share a common origin based on disrupted testicular development during fetal and neonatal stages of life. Male reproductive development is a highly regulated and complex process that relies on an intricate coordination between germ, Leydig, and Sertoli cells as well as other supporting cell types, to ensure proper spermatogenesis, testicular immune privilege, and endocrine function. The eicosanoid system has been reported to be involved in the regulation of fetal and neonatal germ cell development as well as overall testicular homeostasis. Moreover, non-steroidal anti-inflammatory drugs (NSAIDs) and analgesics with abilities to block eicosanoid synthesis by targeting either or both isoforms of cyclooxygenase enzymes, have been found to adversely affect male reproductive development. This review will explore the current body of knowledge on the involvement of the eicosanoid system in male reproductive development, as well as discuss adverse effects of NSAIDs and analgesic drugs administered perinatally, focusing on toxicities reported in the testis and on major testicular cell types. Rodent and epidemiological studies will be corroborated by findings in invertebrate models for a comprehensive report of the state of the field, and to add to our understanding of the potential long-term effects of NSAID and analgesic drug administration in infants.

Can maternal exposure to tamoxifen compromise sperm and behavioural parameters of male rat offspring?

Tamoxifen, a selective non-steroidal estrogen receptor modulator, is the standard adjuvant endocrine treatment for breast cancer. Since information on the risk of using tamoxifen during pregnancy is still scarce, this study evaluated whether the in utero and lactational treatment with this drug could compromise reproductive and behavioural parameters in male offspring. Pregnant Wistar rats were exposed to three doses of tamoxifen (0.12; 0.6; 3 μg/kg), by gavage, from gestational day 15 to lactational day 20. Tamoxifen exposure did not alter the anogenital distance in the male offspring; however, there was a significant increase in the body weight in the 0.12 μg/kg dose and a decrease in the 0.6 μg/kg dose. The male offspring treated with the highest dose exhibited a delay in the onset of puberty, evidenced by an increase in the age of preputial separation. Regarding sperm parameters, there was an increase in the sperm count in the cauda epididymis in the intermediate and highest dose groups, in addition to an increase in the number of static sperm and a decrease in the progressive sperm in the same groups. Moreover, an increase in the number of hyperplasia of the epithelial clear cells was observed in the epididymis. In conclusion, the present study demonstrated that maternal exposure to tamoxifen compromised the installation of puberty of the male offspring and the maturation of the epididymis, affecting sperm storage and motility in the adult life.

Parental exposure to benzo(a)pyrene in the peripubertal period impacts reproductive aspects of the F1 generation in rats

Benzo(a)pyrene (BaP) is an ubiquitous environmental pollutant which can lead to adverse effects on male reproduction. However, the persistence of these changes on a multigenerational scale has not been sufficiently explored. This study evaluated if peripubertal exposure to BaP in male rats can induce reproductive impairment in offspring. Male rats received BaP at environmentally relevant doses (0, 0.1, 1, or 10 μg/kg/day) orally from post-natal (PND) 23-53. On PND 90, treated males were mated with non-treated females for obtaining the next generation (F1). The paternal exposure to BaP decreased the body weight of offspring on PND 1, 13 and 22, as well as it provoked a reduction in the relative anogenital distance of the males. This exposure also brought forward the onset of puberty, evidenced by an earlier vaginal opening and first estrous in females of the lowest dose group and by a delay in the testicular descent and preputial separation ages in males. The males presented a decrease in the daily sperm production and a disrupted sperm morphology. Furthermore, the testicular histology was altered, evidenced by a reduction in the Leydig cell numbers and in the seminiferous tubules diameter, as well as a disrupted seminiferous tubules staging. The estrous cyclicity and some fertility parameters were changed in the females, as well as alterations in the ovary and uterus histology were observed. BaP compromised several reproductive parameters of the F1 generation, suggesting that peripubertal exposure to this compound provokes permanent modifications in male germ line of F0 generation.

Exposure to benzo(a)pyrene from juvenile period to peripubertal impairs male reproductive parameters in adult rats

Benzo(a)pyrene (BaP) is a persistent organic pollutant and endocrine disruptor that can compromise the steroidogenesis process by interacting with the StAR protein, causing adverse effects on male reproduction. However, consequences of prepubertal BaP exposure and its impacts on adult life are yet unknown. This study investigated the effects of BaP exposure from the juvenile period to peripubertal on reproductive parameters in adult male rats. Males were exposed to 0; 0.1; 1 or 10 μg/kg/day of BaP from post-natal (PND) 23 to PND 53 (by gavage). The lowest dose of BaP was able to compromise the male copulatory behavior, as evidenced by the delay in the first mount, intromission and ejaculation. Furthermore, BaP-treated groups showed lower sperm quality (disrupted motility and morphology) and quantity, reduced relative weights of the thyroid and seminal gland. Serum testosterone levels and the Leydig cells nuclei volume were decreased by BaP exposure whereas the StAR expression was increased. Histopathological changes in the testis also were detected in the males exposed to BaP. These results showed that prepubertal BaP-exposure adversely influenced the male reproductive system in the adult life, indicating that a comprehensive risk assessment of BaP-exposure on prepubertal period is necessary.

Pre-pubertal exposure to ibuprofen impairs sperm parameters in male adult rats and compromises the next generation

Ibuprofen is one of the most commonly prescribed anti-inflammatory drugs in pediatric practice. This drug inhibits the cyclooxygenase enzyme, reducing the production of prostaglandin, an important mediator on male reproductive function. We examined if pre-pubertal treatment with ibuprofen in male rats can affect the reproductive parameters of these animals in adult life and on their descendants. Male rats (23 days old) received ibuprofen (0; 2.4; 7.2 or 14.3 mg/kg/day), per gavage, from postnatal day (PND) 23 to 53. At sexual maturity, treated males were placed with untreated females for obtaining the next generation (F1). The highest dose of ibuprofen interfered in sexual behavior and reduced the fertility potential of these animals in adulthood. Additionally, the ibuprofen treatment altered the sperm quantity and quality, as evidenced by a decrease in sperm motility and in the daily sperm production in the testis. Testosterone levels were also reduced by pre-pubertal treatment. The paternal treatment with this drug also influenced the reproductive outcomes of progeny. The male offspring from males treated exhibited acceleration in sperm transit time in the epididymis and the number and volume of Leydig cell nuclei were decreased, while the estrous cyclicity was displayed and the fertility potential reduced in the female offspring. The pre-pubertal ibuprofen-treatment caused negative reproductive impacts in adulthood, compromising sperm quality and quantity, as well as interfered in the reproductive outcomes of the next generation.