The endocannabinoid system and spermatogenesis

Probiotic Lactobacillus rhamnosus modulates MCLR-induced oogenesis disorders in zebrafish: Evidence from the transcriptome

Microcystin-LR (MCLR) produced by cyanobacterial blooms have received global attention. MCLR has been recognized as a reproductive toxin to fish and poses a threat to ecosystem stability. It has been proven that probiotic dietary management can improve reproductive performance of fish. It is worth paying attention to exploring whether probiotic management can alleviate the reproductive toxicity caused by MCLR. In this investigation, adult zebrafish were exposed to different doses of MCLR solution (0, 2.2, and 22 μg/L) with or without the Lactobacillus rhamnosus GG supplementation for a duration of 28 days. The results showed that female zebrafish spawning was reduced after exposure to MCLR, but this reduction was reversed when L. rhamnosus GG was added. To elucidate how L. rhamnosus GG mitigates reproductive toxicity caused by MCLR, we examined a series of indicators of MCLR accumulation, ovarian histology, hormones, and transcriptome levels. Our study showed that L. rhamnosus GG could alleviate oogenesis disorders and ultimately attenuate MCLR-induced reproductive toxicity by reducing MCLR accumulation in the gonads, modulating the expression of endocrine system and auto/paracrine factors. The transcriptome results revealed that single or combined exposure of MCLR and L. rhamnosus GG mainly affected the endocrine system, energy metabolism, and RNA degradation and translation. Overall, our results provide new insights for alleviating MCLR-induced reproductive toxicity and help promote healthy aquaculture.

The effect of LINC9137 targeting miR-140-3p-NKAIN3 signal axis on the development of goose testis sertoli cells

Sertoli cells (SC) are a type of important cells in the testes, which can provide transport proteins, regulatory proteins, growth factors, and other cytokines for the spermatogenic process. They participate in the regulation of the maturation and differentiation of spermatogenic cells and play an important supporting role in the migration, proliferation, and differentiation of germ cells at all levels in the testes. Previous studies found differential expression of LINC9137, miR-140-3p, and Sodium/Potassium Transporting ATPase Interacting 3 (NKAIN3) genesin high and low sperm motility goose testicular tissues. This study investigated the effects of the LINC9137-miR-140-3p-NKAIN3 signal axis on the proliferation and apoptosis of goose testicular sertoli cells at the cellular level, respectively. The results showed that through acridine orange staining, oil red O staining, Alkaline phosphatase (AKP) staining, and RT qPCR assay, it was comprehensively identified that the cultured testicular sertoli cells were purified in vitro. Through the dual luciferase activity detection test, it was found that LINC9137 has a targeted binding site with miR-140-3p and NKAIN3. In addition, this study found that overexpression of miR-140-3p significantly inhibited the expression of LINC9137 and NKAIN3 in sertoli cells, and their expression was significantly increased when miR-140-3p was interfered with. By measuring cell proliferation activity and apoptosis related gene expression, it was found that overexpression of LINC9137 decreased cell proliferation activity (P > 0.05), while the expression level of apoptosis factor Bcl2 Associated X Protein (Bax)/B-cell lymphoma-2 (Bcl2) increased (P > 0.05). On the contrary, when interfering with LINC9137, the cell proliferation activity of sertoli cells was significantly increased (P < 0.01), and the expression level of apoptosis factor Bax/Bcl2 was significantly reduced (P < 0.05); The effect of miR-140-3p on the proliferation and apoptosis of sertoli cells is opposite to that of LINC9137. Meanwhile, this study co transfected overexpressed LINC9137 and miR-140-3p plasmids into sertoli cells, and found that the effect of LINC9137 overexpression on supporting cell proliferation was weakened by miR-140-3p. This study elucidates the role and function of the LINC9137 miR-140-3p-NKAIN3 signaling axis in the development of goose testes and spermatogenesis, establishes a regulatory network related to spermatogenesis, and provides a theoretical basis for studying the genetic regulation of goose spermatogenesis.

Paternal microbiome perturbations impact offspring fitness

The gut microbiota operates at the interface of host-environment interactions to influence human homoeostasis and metabolic networks1-4. Environmental factors that unbalance gut microbial ecosystems can therefore shape physiological and disease-associated responses across somatic tissues5-9. However, the systemic impact of the gut microbiome on the germline-and consequently on the F1 offspring it gives rise to-is unexplored10. Here we show that the gut microbiota act as a key interface between paternal preconception environment and intergenerational health in mice. Perturbations to the gut microbiota of prospective fathers increase the probability of their offspring presenting with low birth weight, severe growth restriction and premature mortality. Transmission of disease risk occurs via the germline and is provoked by pervasive gut microbiome perturbations, including non-absorbable antibiotics or osmotic laxatives, but is rescued by restoring the paternal microbiota before conception. This effect is linked with a dynamic response to induced dysbiosis in the male reproductive system, including impaired leptin signalling, altered testicular metabolite profiles and remapped small RNA payloads in sperm. As a result, dysbiotic fathers trigger an elevated risk of in utero placental insufficiency, revealing a placental origin of mammalian intergenerational effects. Our study defines a regulatory 'gut-germline axis' in males, which is sensitive to environmental exposures and programmes offspring fitness through impacting placenta function.

Hormetic effects of a cannabinoid system component, 2-arachidonoyl glycerol, on cell viability and expression profile of growth factors in cultured mouse Sertoli cells: Friend or foe of male fertility?

The generally undesired effects of exocannabinoids on male reproduction include alterations in testicular cell proliferation and function, as well as apoptosis induction. However, this paradigm has been challenged by the ability of endocannabinoids to regulate reproductive function. The present study addresses these paradoxical facts by investigating the effects of the endocannabinoid 2-arachidonoyl glycerol (2-AG) on mouse Sertoli cells' survival and apoptosis, with a mechanistic insight into Sertoli cell-based growth factors' production. The Mus musculus Sertoli cell line (TM4) was exposed to different concentrations of 2-AG, and cell viability was evaluated using MTT assay. Growth factors' gene and protein expressions were analyzed through RT-PCR and western blotting. 2-AG concentration dependently increased TM4 viability, with a slight increase starting at 0.0001 µM, a peak of 190% of the control level at 1 µM, and a decrease at 3 µM. Moreover, 2-AG paradoxically altered mRNA expression of caspase-3 and growth factors. Caspase-3 mRNA expression was down-regulated, and growth factors mRNA and protein expression were up-regulated when using a low concentration of 2-AG (1 μM). Opposite effects were observed by a higher concentration of 2-AG (3 μM). These paradoxical effects of 2-AG can be explained through the concept of hormesis. The results indicate the pivotal role of 2-AG in mediating Sertoli cell viability and apoptosis, at least in part, through altering growth factors secretion. Furthermore, they suggest the involvement of endocannabinoids in Sertoli cell-based physiological and pathological conditions and reflect the ability of abnormally elevated 2-AG to mimic the actions of exocannabinoids in reproductive dysfunction.

Sperm proteostasis: Can-nabinoids be chaperone's partners?

The male gamete is a highly differentiated cell that aims to fuse with the oocyte in fertilization. Sperm have silenced the transcription and translational processes, maintaining proteostasis to guarantee male reproductive health. Despite the information about the implication of molecular chaperones as orchestrators of protein folding or aggregation, and the handling of body homeostasis by the endocannabinoid system, there is still a lack of basic investigation and random controlled clinical trials that deliver more evidence on the involvement of cannabinoids in reproductive function. Besides, we noticed that the information regarding whether recreational marijuana affects male fertility is controversial and requires further investigation. In other cell models, it has recently been evidenced that chaperones and cannabinoids are intimately intertwined. Through a literature review, we aim to explore the interaction between chaperones and cannabinoid signaling in sperm development and function. To untangle how or whether this dialogue happens within the sperm proteostasis. We discuss the action of chaperones, the endocannabinoid system and phytocannabinoids in sperm proteostasis. Reports of some heat shock and lipid proteins interacting with cannabinoid receptors prove that chaperones and the endocannabinoid system are in an intimate dialogue. Meanwhile, advancing the evidence to decipher these mechanisms for introducing innovative interventions into routine clinical settings becomes crucial. We highlight the potential interaction between chaperones and cannabinoid signaling in regulating proteostasis in male reproductive health.

In vitro evaluation of cell viability and expression profile of growth factors in mouse Sertoli cells exposed to Delta-9-tetrahydrocannabinol: a mechanistic insight into the cannabinoid-induced testicular toxicity

The potentially adverse effects of cannabis (marijuana), a common leisure compound, on male reproductive performance are a reason for concern. δ-9-tetrahydrocannabinol (THC), the primary active component of marijuana alters testicular cells' proliferation and function which affects male fertility and causes testicular cells dysfunction and apoptosis. The main objective of this study was to investigate the possible mechanism underlying the toxic effects of THC with a mechanistic insight into Sertoli cell-based reproductive dysfunction. The Mus musculus Sertoli cell line (TM4) was cultured and exposed to different concentrations of THC and, MTT (3-(4, 5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was then performed for evaluating cell viability. The expression of caspase-3 gene and genes related to growth factors were analyzed by real-time RT-PCR. Western blotting was performed for evaluating protein expression level. THC concentration-dependently decreased the TM4 viability with a significant effect starting at concentration of 1 μM and reaching about 75% of the control level at the concentration of 50 μM (IC25). Moreover, caspase-3 mRNA expression levels significantly increased while growth factors mRNA levels decreased in THC-exposed cells compared to unexposed cells. There was also a significant reduction in related protein levels in THC group. Administration of the THC promotes cytotoxic and apoptotic effects on TM4 cells partly through down-regulation of growth factors expression. Increased apoptosis, over expression of caspase-3, and down-regulation of growth factors expression in Sertoli cells exposed to THC may be a reflection of THC-induced testicular toxicity, which may be partly involved in infertility associated with marijuana smoking or medical cannabis use.

Effect of Docosahexaenoic Acid Encapsulation with Whey Proteins on Rat Growth and Tissue Endocannabinoid Profile

Modifying the food structure allows a nutrient to be delivered differently, which can modify not only its digestion process but also its subsequent metabolism. In this study, rats received 3 g of omelette daily containing docosahexaenoic acid (DHA) as crude oil or previously encapsulated with whey proteins, whereas a control group received a DHA-free omelette. The results showed that DHA encapsulation markedly induced a different feeding behaviour so animals ate more and grew faster. Then, after four weeks, endocannabinoids and other N-acyl ethanolamides were quantified in plasma, brain, and heart. DHA supplementation strongly reduced endocannabinoid derivatives from omega-6 fatty acids. However, DHA encapsulation had no particular effect, other than a great increase in the content of DHA-derived docosahexaenoyl ethanolamide in the heart. While DHA supplementation has indeed shown an effect on cannabinoid profiles, its physiological effect appears to be mediated more through more efficient digestion of DHA oil droplets in the case of DHA encapsulation. Thus, the greater release of DHA and other dietary cannabinoids present may have activated the cannabinoid system differently, possibly more locally along the gastrointestinal tract. However, further studies are needed to evaluate the synergy between DHA encapsulation, fasting, hormones regulating food intake, and animal growth.

Expression of the endocannabinoid system and response to cannabinoid components by the human fetal testis

BACKGROUND

Cannabis consumption by pregnant women continues to increase worldwide, raising concerns about adverse effects on fetal growth and deleterious impacts on the newborn, in connection with evidence of placental transfer of cannabis compound. Cannabis action is mediated by the endocannabinoid system (ECS), which expression is well established in the brain but unknown in the developing testis. The fetal testis, whose endocrine function orchestrates the masculinization of many distant organs, is particularly sensitive to disruption by xenobiotics. In this context, we aimed to determine whether cannabis exposure has the potential to directly impact the human fetal testis.

METHODS

We determined the expression of components of the ECS in the human fetal testis from 6 to 17 developmental weeks and assessed the direct effects of phytocannabinoids Δ9-trans-tetrahydrocannabinol (THC) and cannabidiol (CBD) on the testis morphology and cell functions ex vivo.

RESULTS

We demonstrate the presence in the human fetal testis of two key endocannabinoids, 2-arachidonylglycerol (2-AG) and to a lower level anandamide (AEA), as well as a range of enzymes and receptors for the ECS. Ex vivo exposure of first trimester testes to CBD, THC, or CBD/THC [ratio 1:1] at 10^-7 to 10^-5 M altered testosterone secretion by Leydig cells, AMH secretion by Sertoli cells, and impacted testicular cell proliferation and viability as early as 72 h post-exposure. Transcriptomic analysis on 72 h-exposed fetal testis explants revealed 187 differentially expressed genes (DEGs), including genes involved in steroid synthesis and toxic substance response. Depending on the molecules and testis age, highly deleterious effects of phytocannabinoid exposure were observed on testis tissue after 14 days, including Sertoli and germ cell death.

CONCLUSIONS

Our study is the first to evidence the presence of the ECS in the human fetal testis and to highlight the potential adverse effect of cannabis consumption by pregnant women onto the development of the male gonad.

PRENATAL EXPOSURE TO CB2 RECEPTORS AGONIST DIFFERENTIALLY IMPACTS MALE AND FEMALE GERM CELLS VIA HISTONE MODIFICATION

Cannabis use during pregnancy is increasing in the last few years potentially because of decreased perception of the risk of harm. Regardless, recent evidence demonstrated that prenatal cannabis exposure is associated with adverse outcomes. To date there is limited evidence of the impact of cannabis exposure during pregnancy on the reproductive health of the offspring. The biological effects of cannabis are mediated by two cannabinoid receptors, CB₁ and CB₂. We previously demonstrated that CB₂ is highly expressed in mouse male and female fetal germ cells. In this study, we investigated the effects of prenatal exposure to a selective CB₂ agonist, JWH-133, on the long-term reproductive health of male and female offspring and on the involved molecular epigenetic mechanisms. Notably, we focused on epigenetic histone modifications that can silence or activate gene expression, playing a pivotal role in cell differentiation. We reported that prenatal activation of CB₂ has a sex-specific impact on germ cell development of the offspring. In male it determines a delay of germ cell differentiation coinciding with an enrichment of H3K27me3, while in female it causes a reduction of the follicles number through an increased apoptotic process not linked to modified H3K27me3 level.

AEC and AFMSC Transplantation Preserves Fertility of Experimentally Induced Rat Varicocele by Expressing Differential Regenerative Mechanisms

Amniotic membrane and amniotic fluid derived cells are regarded as a promising stem cell source for developing regenerative medicine techniques, although they have never been tested on male infertility diseases such as varicocele (VAR). The current study aimed to examine the effects of two distinct cell sources, human Amniotic Fluid Mesenchymal Stromal Cells (hAFMSCs) and amniotic epithelial cells (hAECs), on male fertility outcomes in a rat induced VAR model. To explain cell-dependent enhancement of reproductive outcomes in rats transplanted with hAECs and hAFMSCs, insights on testis morphology, endocannabinoid system (ECS) expression and inflammatory tissue response have been carried out alongside cell homing assessment. Both cell types survived 120 days post-transplantation by modulating the ECS main components, promoting proregenerative M2 macrophages (Mφ) recruitment and a favorable anti-inflammatory IL10 expression pattern. Of note, hAECs resulted to be more effective in restoring rat fertility rate by enhancing both structural and immunoresponse mechanisms. Moreover, immunofluorescence analysis revealed that hAECs contributed to CYP11A1 expression after transplantation, whereas hAFMSCs moved towards the expression of Sertoli cell marker, SOX9, confirming a different contribution into the mechanisms leading to testis homeostasis. These findings highlight, for the first time, a distinct role of amniotic membrane and amniotic fluid derived cells in male reproduction, thus proposing innovative targeted stem-based regenerative medicine protocols for remedying high-prevalence male infertility conditions such as VAR.

Endocannabinoid system and epigenetics in spermatogenesis and testicular cancer

In mammals, male germ cell development starts during fetal life and is carried out in postnatal life with the formation of sperms. Spermatogenesis is the complex and highly orderly process during which a group of germ stem cells is set at birth, starts to differentiate at puberty. It proceeds through several stages: proliferation, differentiation, and morphogenesis and it is strictly regulated by a complex network of hormonal, autocrine and paracrine factors and it is associated with a unique epigenetic program. Altered epigenetic mechanisms or inability to respond to these factors can impair the correct process of germ development leading to reproductive disorders and/or testicular germ cell cancer. Among factors regulating spermatogenesis an emerging role is played by the endocannabinoid system (ECS). ECS is a complex system comprising endogenous cannabinoids (eCBs), their synthetic and degrading enzymes, and cannabinoid receptors. Mammalian male germ cells have a complete and active ECS which is modulated during spermatogenesis and that crucially regulates processes such as germ cell differentiation and sperm functions. Recently, cannabinoid receptor signaling has been reported to induce epigenetic modifications such as DNA methylation, histone modifications and miRNA expression. Epigenetic modifications may also affect the expression and function of ECS elements, highlighting the establishment of a complex mutual interaction. Here, we describe the developmental origin and differentiation of male germ cells and testicular germ cell tumors (TGCTs) focusing on the interplay between ECS and epigenetic mechanisms involved in these processes.

Efecto del consumo de marihuana sobre los parámetros espermáticos humanos: Aproximación in vivo

La evidencia sugiere que la exposición a sustancias psicoactivas se relaciona con alteraciones en la espermatogénesis que afectan la calidad espermática. El objetivo de este trabajo fue determinar los parámetros espermáticos en consumidores habituales de cigarrillos de marihuana. Se analizaron muestras seminales de 42 consumidores activos de cigarrillos de marihuana y de 16 voluntarios no consumidores de marihuana. Mediante un análisis de semen, se determinaron los parámetros seminales convencionales (viabilidad, movilidad, morfología, y concentración de los espermatozoides) siguiendo los lineamientos establecidos por la Organización Mundial de la Salud (OMS). Adicionalmente, se evaluó la capacidad antioxidante del plasma seminal mediante la determinación del porcentaje de inhibición del radical estable 1,1-difenil-2-picril-hidracilo. Los valores de la mediana de los consumidores respecto al grupo control fueron: volumen – 2,98 mL versus 3,95 mL (p = 0,0221); concentración total – 189 millones/mL versus 291,1 millones/mL (p = 0,0636); movilidad progresiva – 50% versus 56,5% (p = 0,0052); viabilidad – 65,3% versus 73,1% (p = 0,0732); y morfología normal – 5% versus 7% (p = 0,0167), respectivamente. Los resultados obtenidos en este estudio indican que el consumo de cigarrillos de marihuana afecta negativamente la movilidad progresiva, la morfología normal y la concentración total de espermatozoides; además, la concentración total de espermatozoides está afectada por la frecuencia del consumo de cigarrillos de marihuana.

Cannabis sativa exacerbate testicular function by increased oxidative stress, altered male reproductive hormones, sperm quality/quantity and cellular architecture of the testis

The illicit use of Cannabis in Nigeria is on the increase within the last 10 years and has been implicated as one of the causes of fertility disorder among young men in Nigeria. Hence, this study aimed to ascertain the reproductive impact of n-hexane extract of Cannabis sativa on male Wistar rats. Fifteen male Wistar rats weighing between 180 and 200 g were assigned into three groups of five animals each. The first group served as control, second (low dose), and third (high dose) were fed with n-hexane extract of C. Sativa at doses of 0.75 mg/100 g and 1.5 mg/100 g body weight respectively for 28 days. The administration was done via orogastric. The results revealed the mean serum gonadotropin-releasing hormone (GnRH) concentration in LD and HD was significantly lower (p < 0.05) than in control. LH was significantly higher (p < 0.01) in both LD and HD compared to control. There was a significant increase (p < 0.01) in LD and HD compared to control. Testosterone was significantly elevated in HD (p < 0.05) compared to control. Testicular reduced glutathione and Superoxide dismutase were significantly (p < 0.05) reduced in fed rats compared to control. Testicular catalase and Malondialdehyde were significantly (p < 0.05) increased in HD compared to control. Non-motile sperm count showed a significant (p < 0.001) increase in fed rats compared to control. Total sperm count was significantly (p < 0.05) reduced in fed rats than in control. There were significant (p < 0.001) increased spermatozoa with abnormal morphology in treated groups compared to control. HDL cholesterol was significantly (p < 0.05) elevated in HD compared to control. The atherogenic index was significantly (p < 0.05) reduced in the group fed with 1.5 mg/kg compared to the control. Furthermore, total cholesterol, triglyceride, VLDL-c, and LDL-c did not reveal any significant difference statistically. Histological examination of testes and epididymis of fed rats showed an empty cavity with a reduction in spermatogenesis. This study suggests that n-hexane extract of C. Sativa had more effects on the gonads compared to the higher centres and its ingestion in whatever form could impair male reproductive function.

Vapor cannabis exposure generationally affects male reproductive functions in mice

This study was performed to examine whether vapor exposure to cannabis plant matter negatively impacts male reproductive functions and testis development in mice. Adult CD-1 male mice (F0) were exposed to air (control) or 200 mg of vaporized cannabis plant matter 3x/day over a 10 day period. Subsequently, F0 males were bred with drug naïve CD-1 females to generate F1 males, and F1 offspring were used to generate F2 males. Cannabis vapor exposure decreased sperm count and/or motility in F0 and F1 males and disrupted the progression of germ cell development, as morphometric analyses exhibited an abnormal distribution of the stages of spermatogenesis in F0 males. Although plasma levels of testosterone were not affected by cannabis exposure in any ages or generations of males, dysregulated steroidogenic enzymes, Cyp11a1 and Cyp19a1, were observed in F0 testis. In the neonatal testis from F1 males, while apoptosis was not altered, DNA damage and DNMT1, but not DNMT3A and DNMT3B, were increased in germ cells following cannabis exposure. In contrast, the alterations of DNA damage and DNMT1 expression were not observed in F2 neonatal males. These results suggest that cannabis vapor exposure generationally affects male reproductive functions, probably due to disruption of spermatogenesis in the developing testis.

Diverse role of endocannabinoid system in mammalian male reproduction

Endocannabinoid system (ECS) is known for its modulatory role in numerous physiological processes in the body. Endocannabinoids (eCBs) are endogenous lipid molecules which function both centrally and peripherally. The ECS is best studied in the central nervous system (CNS), immune system as well as in the metabolic system. The role of ECS in male reproductive system is emerging and the presence of a complete enzymatic machinery to synthesize and metabolize eCBs has been demonstrated in male reproductive tract. Endocannabinoid concentrations and alterations in their levels have been reported to affect the functioning of spermatozoa. A dysfunctional ECS has also been linked to the development of prostate cancer, the leading cause of cancer related mortality among male population. This review is an attempt to provide an insight into the significant role of endocannabinoids in male reproduction and further summarize recent findings that demonstrate the manner in which the endocannabinoid system impacts male sexual behavior and fertility.

Decreasing sperm quality in mice subjected to chronic cannabidiol exposure: New insights of cannabidiol-mediated male reproductive toxicity

Cannabidiol (CBD) is a natural cannabinoid present in the Cannabis sativa plant, widely prescribed as an anticonvulsant drug, especially for pediatric use. However, its effects on male reproduction are still little investigated. Therefore, the present study assessed the effects of CBD on the spermatogenesis and sperm quality. For this, twenty-one-day-old Swiss mice received CBD for 34 consecutive days by gavage at doses of either 15 or 30 mg/kg. Chronic exposure to CBD decreased the frequency of stages VII-VIII and XII of spermatogenesis and an increase in the frequency of stage IX were noted. Furthermore, the seminiferous epithelium height reduced at stage IX and increased at stage XII in both CBD-treated groups. There was a significant rise of sperm DNA damage, while no genotoxic effects were observed in leukocytes. The activities of superoxide dismutase and catalase decreased, while malondialdehyde levels increased in the sperm of mice treated with a higher dose of CBD. Mice exposed to 30 mg/kg of CBD showed a reduction in the mobile spermatozoa percentage and in curvilinear velocity, while straight line and average path velocity decreased in both treated groups. The number of acrosome-intact spermatozoa declined in the CBD 30 group, and the number of abnormal acrosomes raised in both CBD groups. On the other hand, the weight of reproductive organs, sperm count, and hormone levels were not affected by CBD treatment. These findings show that dysregulation of the endocannabinoid system by CBD can reduce sperm quality. The mechanisms responsible may be associated with disorders during spermatogenesis, especially during the final stages of nuclear remodelling and assembly of acrosome. However, changes in mitochondrial function, as well as the reduction on the antioxidant enzyme activities during epididymal transit, at least partly, may also be involved.

Identification and function prediction of novel microRNAs in adenosine monophosphate activated protein kinase-activated Sertoli cells of immature boar

This study was carried out with the objective to identify function prediction of novel microRNAs (miRNAs) in immature boar Sertoli cells (SCs) treated with 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR), which is an agonist of adenosine monophosphate-activated protein kinase (AMPK) for regulating cellular energy homeostasis. Two small RNA libraries (control and AICAR treatment) prepared from immature boar SCs were constructed and sequenced by the Illumina small RNA deep sequencing. We identified 77 novel miRNAs and predicted 177 potential target genes for 26 differential novel miRNAs (four miRNAs up-regulation and 22 miRNAs down-regulation) in AICAR-treated SCs. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway suggested that target genes of differential novel miRNAs were implicated in many biological processes and metabolic pathways. Our findings provided useful information for the functional regulation of novel miRNAs and target mRNAs on AMPK-activated immature boar SCs.

In Vitro and In Vivo Pretreatment with Selenium Mitigates Tetrahydrocannabinol-Induced Testicular Cell Apoptosis: the Role of AKT and p53 Pathways

Exocannabinoids such as tetrahydrocannabinol (THC) may alter the physiological function of endocannabinoids in male reproduction and thus affect male fertility. This study aimed to investigate the apoptotic effects of THC via mechanisms related to p53 and AKT signaling pathways on Sertoli cells and seminiferous germinal cells, as well as the possible protective role of selenium pretreatment in both in vitro and in vivo models. The Mus musculus Sertoli cell line, TM4, was used for in vitro experiments. The TM4 cells were cultured and exposed to selenium (2 μM, 48 h) and THC (470 μM, 24 h). The MTT test was performed to evaluate cell viability. Fifteen male Wistar rats (220 ± 20 g) were used for in vivo experiments and divided into three groups: (1) control, (2) tetrahydrocannabinol (THC, 5 mg/kg, dissolved in DMSO 5%, i.p., for 21 consecutive days), and (3) THC + selenium (selenium, 0.5 mg/kg per day, i.p.). At the end of the experiments, Sertoli cells and testis tissue samples were collected for biochemical (AKT, P53), cell apoptosis, and histological analyses. The results of the in vitro study revealed that THC significantly decreases the cell viability (p < 0.001) and expression of the p-AKt protein (p < 0.05) and increases Sertoli cells' apoptosis (p < 0.001) and p53 protein expression (p < 0.001). The in vivo effects of THC were in line with the in vitro results. Pretreatment with selenium (as sodium selenite) significantly decreased the THC-induced Sertoli cell and testicular tissue damages in the rats. Pathological changes were significantly alleviated in the selenium-pretreated rats. Collectively, these data suggest that pretreatment with selenium is able to protect against THC-induced testicular cell damage. The attenuating effect of selenium may be due to its anti-apoptotic activity through the p53 and AKT modulation.

Male Preconception Marijuana Use and Spontaneous Abortion: A Prospective Cohort Study

BACKGROUND

Male marijuana use has increased steadily over the last decade, but its effect on risk of spontaneous abortion to our knowledge has not been studied.

METHODS

We analyzed data from Pregnancy Study Online, a North American prospective cohort study of pregnancy planners (2013-2019). During the preconception period, male and female participants completed baseline questionnaires on demographics, medical history, and behavioral factors, including marijuana use. Female participants identified pregnancy losses on bimonthly follow-up questionnaires and questionnaires completed in early and late pregnancy. We categorized frequency of male marijuana use in the 2 months before baseline as none, <1 time/week, or ≥1 time/week. We estimated the association between preconception male marijuana use and spontaneous abortion, adjusting for male and female confounders.

RESULTS

Among 1535 couples who conceived during follow-up, 9% of men reported preconceptional marijuana use <1 time/week and 8% ≥1 time/week. Nineteen percent of pregnancies ended in spontaneous abortion. Compared with no use, adjusted hazard ratios (HRs) for male marijuana use were 1.1 (95% confidence interval [CI] = 0.64, 1.7) for <1 time/week and 2.0 (95% CI = 1.2, 3.1) for ≥1 time/week. The association for ≥1 time/week persisted after restricting to couples where the female partner did not use marijuana (HR = 2.0, 95% CI = 1.1, 3.3), and was stronger for losses at <8 weeks' gestation (HR = 2.5, 95% CI = 1.4, 4.3) and among males aged ≥35 years (HR = 4.1, 95% CI = 1.54, 11).

CONCLUSIONS

Couples with male partners who used marijuana ≥1 time/week during preconception had greater risk of spontaneous abortion than couples with males who did not use marijuana.

Bisphenol A Deranges the Endocannabinoid System of Primary Sertoli Cells with an Impact on Inhibin B Production

Bisphenol A (BPA) is an endocrine disruptor that negatively affects spermatogenesis, a process where Sertoli cells play a central role. Thus, in the present study we sought to ascertain whether BPA could modulate the endocannabinoid (eCB) system in exposed mouse primary Sertoli cells. Under our experimental conditions, BPA turned out to be cytotoxic to Sertoli cells with an half-maximal inhibitory concentration (IC₅₀) of ~6.0 µM. Exposure to a non-cytotoxic dose of BPA (i.e., 0.5 μM for 48 h) increased the expression levels of specific components of the eCB system, namely: type-1 cannabinoid (CB₁) receptor and diacylglycerol lipase-α (DAGL-α), at mRNA level, type-2 cannabinoid (CB₂) receptor, transient receptor potential vanilloid 1 (TRPV1) receptors, and DAGL-β, at protein level. Interestingly, BPA also increased the production of inhibin B, but not that of transferrin, and blockade of either CB₂ receptor or TRPV1 receptor further enhanced the BPA effect. Altogether, our study provides unprecedented evidence that BPA deranges the eCB system of Sertoli cells towards CB₂- and TRPV1-dependent signal transduction, both receptors being engaged in modulating BPA effects on inhibin B production. These findings add CB₂ and TRPV1 receptors, and hence the eCB signaling, to the other molecular targets of BPA already known in mammalian cells.

Activation of the cannabinoid receptor type 2 by the agonist JWH133 promotes the first wave of in vitro spermatogenesis

BACKGROUND

Oncological procedures have irreversible side effects on germ cells for childhood cancer survival boys. In vitro culture of prepubertal testicular tissue has been proposed to restore fertility; however, recent data on animal models showed that meiotic and post-meiotic progression was impaired.

OBJECTIVES

As potential key inducers of the mitosis-meiosis switch, type 2 cannabinoid receptor (CB₂ ) has been proposed to play a central role in the meiotic entry of male germ cells. Herein, the in vitro first spermatogenesis wave in mice was used to understand the impact of CB₂ activation on the differentiation of spermatogonia until elongated spermatids.

MATERIALS AND METHODS

A first set of cultured testicular explants of 6.5 days post-partum (dpp) mice was performed to assess the impact of a range of JWH133 supplementation (10 nm, 100 nm, 1 µm, 10 µm). Then, the progressive development of germ cells at key timepoints of spermatogenesis was evaluated throughout (i) in vitro culture (day 2 [D2], D3, D6, D10, D18, and D30) coupled with (ii) in vivo counterparts (8.5, 9.5, 12.5, 16.5, 24.5, and 36.5 dpp).

RESULTS

CB₂ was detected at the plasma membrane of cells, and a successful completion of spermatogenesis was obtained in vitro. One day after the activation of CB₂ by 1 μm of the agonist JWH133, percentage of zygotene spermatocyte I increased.

CONCLUSION

After 30 days of culture, (i) an enrichment of haploid germ cells detected by flow cytometry, (ii) a reduced necrotic area, and (iii) an increase in the density of post-meiotic germ cells were observed. We showed that the activation of CB₂ improves in vitro entry into meiosis and differentiation of spermatogonia, mimicking physiological meiotic transition.

Impact of tetrahydrocannabinol on the endocannabinoid 2-arachidonoylglycerol metabolism: ABHD6 and ABHD12 as novel players in human placenta

Cannabis use has been increasing worldwide for recreational and medical purposes. Consumption by pregnant women is associated with disturbances in pregnancy outcome, such as low birth weight, prematurity and intrauterine growth retardation, though the underlying biochemical mechanisms are unknown. The endocannabinoid system is involved in several reproductive events and the disruption of its homeostasis by ∆⁹-tetrahydrocannabinol (THC), the main psychoactive cannabinoid, may lead to a negative gestational outcome. In human placenta, THC impairs the levels of the endocannabinoid anandamide (AEA). The other major endocannabinoid, 2-arachidonoylglycerol (2-AG) also plays an important role on proper placentation and pregnancy success. However, THC impact on 2-AG homeostasis has never been addressed. Hence, the effects of THC in 2-AG levels and metabolic enzymes expression were explored. Long-term treatment impairs the expression of the main 2-AG synthetic and degradative enzymes. Curiously, with the highest concentration, despite the maintenance of diacylglycerol lipase alpha (DAGLα) and the decrease in monoacylglycerol lipase (MAGL) expression, 2-AG levels remain constant. Given the endocannabinoid signalling local tight regulation, we hypothesize the involvement of other 2-AG degradative enzymes. Indeed, THC increases the expression of the hydrolyzing enzymes alpha beta hydrolase domain-6 (ABHD6) and -12 (ABHD12), that we firstly describe in human placental tissues. The results show that THC, depending on time of exposure, induces alterations in 2-AG metabolic enzymes expression in placental explants, highlighting the importance of 2-AG regulation and endocannabinoid signalling in placental development. Alterations in this homeostasis may explain the negative pregnancy outcome related to cannabis consumption.

Environmental Impact on Male (In)Fertility via Epigenetic Route

In the last 40 years, male reproductive health-which is very sensitive to both environmental exposure and metabolic status-has deteriorated and the poor sperm quality observed has been suggested to affect offspring development and its health in adult life. In this scenario, evidence now suggests that epigenetics shapes endocrine functions, linking genetics and environment. During fertilization, spermatozoa share with the oocyte their epigenome, along with their haploid genome, in order to orchestrate embryo development. The epigenetic signature of spermatozoa is the result of a dynamic modulation of the epigenetic marks occurring, firstly, in the testis-during germ cell progression-then, along the epididymis, where spermatozoa still receive molecules, conveyed by epididymosomes. Paternal lifestyle, including nutrition and exposure to hazardous substances, alters the phenotype of the next generations, through the remodeling of a sperm epigenetic blueprint that dynamically reacts to a wide range of environmental and lifestyle stressors. With that in mind, this review will summarize and discuss insights into germline epigenetic plasticity caused by environmental stimuli and diet and how spermatozoa may be carriers of induced epimutations across generations through a mechanism known as paternal transgenerational epigenetic inheritance.

Marijuana smoking and markers of testicular function among men from a fertility centre

STUDY QUESTION

Is marijuana smoking associated with semen quality, sperm DNA integrity or serum concentrations of reproductive hormones among subfertile men?

SUMMARY ANSWER

Men who had ever smoked marijuana had higher sperm concentration and count and lower serum FSH concentrations than men who had never smoked marijuana; no differences were observed between current and past marijuana smokers.

WHAT IS KNOWN ALREADY

Studies of marijuana abuse in humans and animal models of exposure to marijuana suggest that marijuana smoking adversely impacts spermatogenesis. Data is less clear for moderate consumption levels and multiple studies have found higher serum testosterone concentrations among marijuana consumers.

STUDY DESIGN, SIZE, DURATION

This longitudinal study included 662 subfertile men enroled at the Massachusetts General Hospital Fertility Center between 2000 and 2017. The men provided a total of 1143 semen samples; 317 men also provided blood samples in which we measured reproductive hormones.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Use of marijuana and other drugs was self-reported at baseline. Standard protocols were followed for measuring semen quality, sex hormones and DNA integrity. We used linear mixed effect models with a random intercept to evaluate the associations of self-reported marijuana smoking at enrolment with semen parameters from subsequently collected samples, and linear regression models for sperm DNA integrity and serum reproductive hormones, while adjusting for confounders including smoking and cocaine use.

MAIN RESULTS AND THE ROLE OF CHANCE

Men who had ever smoked marijuana (N = 365) had significantly higher sperm concentration (62.7 (95% confidence interval: 56.0, 70.3) million/mL) than men who had never smoked marijuana (N = 297) (45.4 (38.6, 53.3) million/mL) after adjusting for potential confounders (P = 0.0003). There were no significant differences in sperm concentration between current (N = 74) (59.5 (47.3, 74.8) million/mL) and past marijuana smokers (N = 291) (63.5 (56.1, 72.0) million/mL; P = 0.60). A similar pattern was observed for total sperm count. Furthermore, the adjusted prevalence of sperm concentration and total sperm motility below WHO reference values among marijuana smokers was less than half that of never marijuana smokers. Marijuana smokers had significantly lower follicle stimulating hormone (FSH) concentrations than never marijuana smokers (-16% (-27%, -4%)) and there were no significant differences between current and past marijuana smokers (P = 0.53). Marijuana smoking was not associated with other semen parameters, with markers of sperm DNA integrity or with reproductive hormones other than FSH. Chance findings cannot be excluded due to the multiple comparisons.

LIMITATIONS, REASONS FOR CAUTION

Our results may not be generalisable to men from the general population. Marijuana smoking was self-reported and there may be misclassification of the exposure.

WIDER IMPLICATIONS OF THE FINDINGS

These findings are not consistent with a deleterious effect of marijuana on testicular function. Whether these findings are reflective of the previously described role of the endocannabinoid system in spermatogenesis or a spurious association requires confirmation in further studies.

STUDY FUNDING/COMPETING INTEREST(S)

The project was funded by grants R01ES009718 and P30ES000002 from the National Institute of Environmental Health Sciences (NIEHS). None of the authors has any conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Delta-9 THC can be detected and quantified in the semen of men who are chronic users of inhaled cannabis

PURPOSE

The purpose of this proof-of-concept study was to determine whether delta-9-tetrahydrocannabinol (THC) and THC metabolites (11-OH THC and THC-COOH) can be detected in semen.

METHODS

Twelve healthy men aged 18-45 years who identified as chronic and heavy users of inhaled cannabis were recruited. THC and THC metabolite levels were measured in serum, urine, and semen of the participants. Semen analyses were performed. Serum reproductive hormones were measured.

RESULTS

The median age and BMI of participants were 27.0 years and 24.7 kg/m², respectively. Over half the participants were daily users of cannabis for over 5 years. Serum reproductive hormones were generally within normal ranges, except prolactin, which was elevated in 6 of 12 participants (mean 13.9 ng/mL). The median sperm concentration, motility, and morphology were 75.5 million/mL, 69.5%, and 5.5%, respectively. Urinary THC-COOH was detected in all 12 participants, and at least one serum THC metabolite was present in 10 of 12 participants. Two semen samples had insufficient volume to be analyzed. THC was above the reporting level of 0.50 ng/mL in the semen of two of the remaining participants. Seminal THC was moderately correlated with serum levels of THC (r = 0.66), serum 11-OH THC (r = 0.57), and serum THC-COOH (r = 0.67). Seminal delta-9 THC was not correlated with urinary cannabinoid levels or semen analysis parameters.

CONCLUSION

This is the first study to identify and quantify THC in human semen, demonstrating that THC can cross the blood-testis barrier in certain individuals. Seminal THC was found to be moderately correlated with serum THC and THC metabolites.

Cannabinoid Receptors Signaling in the Development, Epigenetics, and Tumours of Male Germ Cells

Endocannabinoids are natural lipid molecules whose levels are regulated by specific biosynthetic and degradative enzymes. They bind to and activate two main cannabinoid receptors type 1 (CB₁) and type 2 (CB₂), and together with their metabolizing enzymes form the “endocannabinoid system” (ECS). In the last years, the relevance of endocannabinoids (eCBs) as critical modulators in various aspects of male reproduction has been pointed out. Mammalian male germ cells, from mitotic to haploid stage, have a complete ECS which is modulated during spermatogenesis. Compelling evidence indicate that in the testis an appropriate “eCBs tone”, associated to a balanced CB receptors signaling, is critical for spermatogenesis and for the formation of mature and fertilizing spermatozoa. Any alteration of this system negatively affects male reproduction, from germ cell differentiation to sperm functions, and might have also an impact on testicular tumours. Indeed, most of testicular tumours develop during early germ-cell development in which a maturation arrest is thought to be the first key event leading to malignant transformation. Considering the ever-growing number and complexity of the data on ECS, this review focuses on the role of cannabinoid receptors CB₁ and CB₂ signaling in male germ cells development from gonocyte up to mature spermatozoa and in the induction of epigenetic alterations in these cells which might be transmitted to the progeny. Furthermore, we present new evidence on their relevance in testicular cancer.

Effects of Dietary Bisphenol A on the Reproductive Function of Gilthead Sea Bream (Sparus aurata) Testes

Bisphenol A (BPA), a known endocrine disrupting chemical (EDC), was administered by diet to gilthead sea bream (Sparus aurata) in order to study its effects on the endocannabinoid system (ECS) and gonadal steroidogenesis. 2-year-old male gilthead sea bream were fed with two different concentrations of BPA (LOW at 4 and HIGH at 4000 µg/kg body weight for 21 days during the reproductive season. Exposure to 4000 µg BPA/kg bw/day (BPA HIGH) reduced sperm motility and altered the straight-line velocity (VSL) and linearity (LIN). Effects on steroidogenesis were evident, with testosterone (T) being up-regulated by both treatments and 11-ketotestosterone (11-KT) down-regulated by BPA HIGH. Plasma levels of 17β-estradiol (E₂) were not affected. The Gonadosomatic Index (GSI) increased in the BPA HIGH group. Interestingly, the levels of endocannabinoids and endocannabinoid-like compounds were significantly reduced after both treatments. Unpredictably, a few changes were noticed in the expression of genes coding for ECS enzymes, while the receptors were up-regulated depending on the BPA dose. Reproductive markers in testis (leptin receptor (lepr), estrogen receptors (era, erb), progesterone receptors (pr) and the gonadotropin releasing hormone receptor (gnrhr)) were up-regulated. BPA induced the up-regulation of the hepatic genes involved in oogenesis (vitellogenin (vtg) and zona pellucida 1 (zp1)).

Characterisation and localisation of the endocannabinoid system components in the adult human testis

Heavy use of cannabis (marijuana) has been associated with decreased semen quality, which may reflect disruption of the endocannabinoid system (ECS) in the male reproductive tract by exogenous cannabinoids. Components of ECS have been previously described in human spermatozoa and in the rodent testis but there is little information on the ECS expression within the human testis. In this study we characterised the main components of the ECS by immunohistochemistry (IHC) on archived testis tissue samples from 15 patients, and by in silico analysis of existing transcriptome datasets from testicular cell populations. The presence of 2-arachidonoylglycerol (2-AG) in the human testis was confirmed by matrix-assisted laser desorption ionization imaging analysis. Endocannabinoid-synthesising enzymes; diacylglycerol lipase (DAGL) and N-acyl-phosphatidylethanolamine-specific phospholipase D (NAPE-PLD), were detected in germ cells and somatic cells, respectively. The cannabinoid receptors, CNR1 and CNR2 were detected at a low level in post-meiotic germ cells and Leydig- and peritubular cells. Different transcripts encoding distinct receptor isoforms (CB1, CB1A, CB1B and CB2A) were also differentially distributed, mainly in germ cells. The cannabinoid-metabolising enzymes were abundantly present; the α/β-hydrolase domain-containing protein 2 (ABHD2) in all germ cell types, except early spermatocytes, the monoacylglycerol lipase (MGLL) in Sertoli cells, and the fatty acid amide hydrolase (FAAH) in late spermatocytes and post-meiotic germ cells. Our findings are consistent with a direct involvement of the ECS in regulation of human testicular physiology, including spermatogenesis and Leydig cell function. The study provides new evidence supporting observations that recreational cannabis can have possible deleterious effects on human testicular function.

Selective Cannabinoid 2 Receptor Agonists as Potential Therapeutic Drugs for the Treatment of Endotoxin-Induced Uveitis

(1) Background: The cannabinoid 2 receptor (CB₂R) is a promising anti-inflammatory drug target and development of selective CB₂R ligands may be useful for treating sight-threatening ocular inflammation. (2) Methods: This study examined the pharmacology of three novel chemically-diverse selective CB₂R ligands: CB₂R agonists, RO6871304, and RO6871085, as well as a CB₂R inverse agonist, RO6851228. In silico molecular modelling and in vitro cell-based receptor assays were used to verify CB₂R interactions, binding, cell signaling (ß-arrestin and cAMP) and early absorption, distribution, metabolism, excretion, and toxicology (ADMET) profiling of these receptor ligands. All ligands were evaluated for their efficacy to modulate leukocyte-neutrophil activity, in comparison to the reported CB₂R ligand, HU910, using an in vivo mouse model of endotoxin-induced uveitis (EIU) in wild-type (WT) and CB₂R^-/- mice. The actions of RO6871304 on neutrophil migration and adhesion were examined in vitro using isolated neutrophils from WT and CB₂R^-/- mice, and in vivo in WT mice with EIU using adoptive transfer of WT and CB₂R^-/- neutrophils, respectively. (3) Results: Molecular docking studies indicated that RO6871304 and RO6871085 bind to the orthosteric site of CB₂R. Binding studies and cell signaling assays for RO6871304 and RO6871085 confirmed high-affinity binding to CB₂R and selectivity for CB₂R > CB₁R, with both ligands acting as full agonists in cAMP and ß-arrestin assays (EC₅₀s in low nM range). When tested in EIU, topical application of RO6871304 and RO6871085 decreased leukocyte-endothelial adhesion and this effect was antagonized by the inverse agonist, RO6851228. The CB₂R agonist, RO6871304, decreased in vitro neutrophil migration of WT neutrophils but not neutrophils from CB₂R^-/-, and attenuated adhesion of adoptively-transferred leukocytes in EIU. (4) Conclusions: These unique ligands are potent and selective for CB₂R and have good immunomodulating actions in the eye. RO6871304 and RO6871085, as well as HU910, decreased leukocyte adhesion in EIU through inhibition of resident ocular immune cells. The data generated with these three structurally-diverse and highly-selective CB₂R agonists support selective targeting of CB₂R for treating ocular inflammatory diseases.

CircNAPEPLD is expressed in human and murine spermatozoa and physically interacts with oocyte miRNAs

Circular RNAs (circRNAs) have a critical role in the control of gene expression. Their function in spermatozoa (SPZ) is unknown to date. Twenty-eight genes, involved in SPZ/testicular and epididymal physiology, were given in circBase database to find which of them may generate circular transcripts. We focused on circNAPEPLDiso1, one of the circular RNA isoforms of NAPEPLD transcript, because expressed in human and murine SPZ. In order to functionally characterize circNAPEPLDiso1 as potential microRNA (miRNA) sponge, we performed circNAPEPLDiso1-miR-CATCH and then profiled the expression of 754 miRNAs, by using TaqMan® Low Density Arrays. Among them, miRNAs 146a-5p, 203a-3p, 302c-3p, 766-3p and 1260a (some of them previously shown to be expressed in the oocyte), resulted enriched in circNAPEPLDiso1-miR-CATCHed cell lysate: the network of interactions generated from their validated targets was centred on a core of genes involved in the control of cell cycle. Moreover, computational analysis of circNAPEPLDiso1 sequence also showed its potential translation in a short form of NAPEPLD protein. Interestingly, the expression analysis in murine-unfertilized oocytes revealed low and high levels of circNAPEPLDiso1 and circNAPEPLDiso2, respectively. After fertilization, circNAPEPLDiso1 expression significantly increased, instead circNAPEPLDiso2 expression appeared constant. Based on these data, we suggest that SPZ-derived circNAPEPLDiso1 physically interacts with miRNAs primarily involved in the control of cell cycle; we hypothesize that it may represent a paternal cytoplasmic contribution to the zygote and function as a miRNA decoy inside the fertilized oocytes to regulate the first stages of embryo development. This role is proposed here for the first time.

Identification of microRNAs for regulating adenosine monophosphate-activated protein kinase expression in immature boar Sertoli cells in vitro

Adenosine monophosphate-activated protein kinase (AMPK) plays a key role in cellular energy homeostasis and cell proliferation. MicroRNAs (miRNAs) function as posttranscriptional regulators of gene expression in biological processes. It is unclear to whether miRNAs are involved in AMPK-regulated Sertoli cell (SC) proliferation. To further understand the regulation of miRNAs in the immature boar SC proliferation, 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) was added to activate AMPK. By an Illumina small RNA deep sequencing, we obtained sequences and relative expression levels of 272 known mature miRNAs, among which 9 miRNAs were significantly upregulated whereas 16 miRNAs were downregulated following the AICAR treatment. The results identified 38 conserved miRNAs, with 8 significantly downregulated miRNAs whereas no upregulated miRNAs. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analyses suggested that miR-1285 was involved in many activities and pathways associated with cell proliferation via targeting on AMPKα2. We validated that AICAR significantly downregulated miR-1285 level in SCs. Transfection of miR-1285 mimic increased the SC viability and cell cycle progression but reduced AMPKα2 mRNA and protein levels, indicating that miR-1285 is involved in the immature boar SC proliferation via downregulating AMPKα2 expression.

Effects of cannabis tetrahydrocannabinol on endocannabinoid homeostasis in human placenta

Cannabis use has become a hot topic in several countries due to the debate about its legalization for medical purposes. However, data are limited regarding adverse events, safety and potential impact on reproductive health. Cannabis consumption during pregnancy has been associated with gestational disorders such as preterm birth, intrauterine growth restriction, low birth weight and increased risk of miscarriage, though the underlying biochemical mechanisms are still unknown. Given that the endocannabinoid system (ECS) is involved in several reproductive processes, we tested the hypothesis that the negative outcomes may result from the impact on the ECS homeostasis caused by the main psychoactive compound of cannabis, Δ⁹-tetrahydrocannabinol (THC). We demonstrate that THC (10-40 µM) impairs placental endocannabinoid system by disrupting the endocannabinoid anandamide (AEA) levels and the expression of AEA synthetic and degrading enzymes N-arachidonoylphosphatidylethanolamine-specific phospholipase D (NAPE-PLD) and fatty acid amide hydrolase (FAAH), respectively. Although, no alterations in cannabinoid receptors CB1 and CB2 expression were observed. Thus, long-term local AEA levels are associated with a shift in the enzymatic profile to re-establish ECS homeostasis. In chronic cannabis users, high AEA levels in placenta may disturb the delicate balance of trophoblast cells turnover leading to alterations in normal placental development and foetal growth.

Artificial Neural Network to Predict Varicocele Impact on Male Fertility through Testicular Endocannabinoid Gene Expression Profiles

The relationship between varicocele and fertility has always been a matter of debate because of the absence of predictive clinical indicators or molecular markers able to define the severity of this disease. Even though accumulated evidence demonstrated that the endocannabinoid system (ECS) plays a central role in male reproductive biology, particularly in the testicular compartment, to date no data point to a role for ECS in the etiopathogenesis of varicocele. Therefore, the present research has been designed to investigate the relationship between testicular ECS gene expression and fertility, using a validated animal model of experimental varicocele (VAR), taking advantage of traditional statistical approaches and artificial neural network (ANN). Experimental induction of VAR led to a clear reduction of spermatogenesis in left testes ranging from a mild (Johnsen score 7: 21%) to a severe (Johnsen score 4: 58%) damage of the germinal epithelium. However, the mean number of new-borns recorded after two sequential matings was quite variable and independent of the Johnsen score. While the gene expression of biosynthetic and degrading enzymes of AEA (NAPE-PLD and FAAH, respectively) and of 2-AG (DAGLα and MAGL, respectively), as well as their binding cannabinoid receptors (CB1 and CB2), did not change between testes and among groups, a significant downregulation of vanilloid (TRPV1) expression was recorded in left testes of VAR rats and positively correlated with animal fertility. Interestingly, an ANN trained by inserting the left and right testicular ECS gene expression profiles (inputs) was able to predict varicocele impact on male fertility in terms of mean number of new-borns delivered (outputs), with a very high accuracy (average prediction error of 1%). The present study provides unprecedented information on testicular ECS gene expression patterns during varicocele, by developing a freely available predictive ANN model that may open new perspectives in the diagnosis of varicocele-associated infertility.

Disruption of the gonadal endocannabinoid system in zebrafish exposed to diisononyl phthalate

DiNP (Di-isononyl phthalate) has been recently introduced as DEHP (Bis (2-ethylhexyl) phthalate) substitute and due to its chemical properties, DiNP is commonly used in a large variety of plastic items. The endocannabinoid system (ECS) is a lipid signaling system involved in a plethora of physiological pathways including the control of the reproductive and metabolic processes. In this study, the effects of DiNP on the ECS of zebrafish (male and female) gonads were analyzed. Adult zebrafish were chronically exposed for 21 days via water to 3 environmentally relevant concentrations of DiNP (42 μg/L; 4.2 μg/L; 0.42 μg/L). In females, the Gonadosomatic Index (GSI) and the number of fertilized eggs were reduced by the lowest concentration of DiNP tested. The levels of two endocannabinoids, Anandamide (AEA) and 2-Arachidonoylglycerol (2-AG), were not affected, while a reduction of the N-oleoyl-ethanolamine (OEA) level was observed. Transcriptional changes were reported in relation to genes coding for the ECS receptors and the enzymes involved in the ECS pathway. DiNP exposure in males reduced the GSI as well as changed the levels of endocannabinoids. Moreover, DiNP treatment induced significative changes in the genes coding for the ECS receptors and enzymes, and significantly increased the activity of the fatty acid amide hydrolase (FAAH). In summary, in zebrafish, exposure to environmentally relevant concentrations of DiNP disrupted the ECS and affected reproduction in a gender specific manner.

MicroRNA-7450 regulates non-thermal plasma-induced chicken Sertoli cell apoptosis via adenosine monophosphate-activated protein kinase activation

Non-thermal plasma treatment is an emerging innovative technique with a wide range of biological applications. This study was conducted to investigate the effect of a non-thermal dielectric barrier discharge plasma technique on immature chicken Sertoli cell (SC) viability and the regulatory role of microRNA (miR)-7450. Results showed that plasma treatment increased SC apoptosis in a time- and dose-dependent manner. Plasma-induced SC apoptosis possibly resulted from the excess production of reactive oxygen species via the suppression of antioxidant defense systems and decreased cellular energy metabolism through the inhibition of adenosine triphosphate (ATP) release and respiratory enzyme activity in the mitochondria. In addition, plasma treatment downregulated miR-7450 expression and activated adenosine monophosphate-activated protein kinase α (AMPKα), which further inhibited mammalian target of rapamycin (mTOR) phosphorylation in SCs. A single-stranded synthetic miR-7450 antagomir disrupted mitochondrial membrane potential and decreased ATP level and mTOR phosphorylation by targeting the activation of AMPKα, which resulted in significant increases in SC lethality. A double-stranded synthetic miR-7450 agomir produced opposite effects on these parameters and ameliorated plasma-mediated apoptotic effects on SCs. Our findings suggest that miR-7450 is involved in the regulation of plasma-induced SC apoptosis through the activation of AMPKα and the further inhibition of mTOR signaling pathway.

Analysis of Endocannabinoid System in Rat Testis During the First Spermatogenetic Wave

Endocannabinoids are lipid mediators, enzymatically synthesized and hydrolyzed, that bind cannabinoid receptors. Together with their receptors and metabolic enzymes, they form the "endocannabinoid system" (ECS). Anandamide (AEA) and 2-arachidonoylglycerol (2-AG) are the main endocannabinoids studied in testis. In this study, using the first wave of spermatogenesis as an in vivo model to verify the progressive appearance of germ cells in seminiferous tubules [i.e., spermatogonia, spermatocytes, and spermatids], we analyzed the expression of the main enzymes and receptors of ECS in rat testis. In particular, the expression profile of the main enzymes metabolizing AEA and 2-AG as well as the expression of cannabinoid receptors, such as CB1 and CB2, and specific markers of mitotic, meiotic, and post-meiotic germ cell appearance or activities have been analyzed by RT-PCR and appropriately correlated. Our aim was to envisage a relationship between expression of ECS components and temporal profile of germ cell appearance or activity as well as among ECS components. Results show that expression of ECS components is related to germ cell progression. In particular, CB2 and 2-AG appear to be related to mitotic/meiotic stages, while CB1 and AEA appear to be related to spermatogonia stem cells activity and spermatids appearance, respectively. Our data also suggest that a functional interaction among ECS components occurs in the testis. Indeed, in vitro-incubated testis show that AEA-CB2 activity affects negatively monoacylglycerol-lipase levels via upregulation of CB1 suggesting a CB1/CB2-mediated relationship between AEA and 2-AG. Finally, we provide the first evidence that CB1 is present in fetal gonocytes, during mitotic arrest.

miR-762 promotes porcine immature Sertoli cell growth via the ring finger protein 4 (RNF4) gene

A growing number of reports have revealed that microRNAs (miRNAs) play critical roles in spermatogenesis. Our previous study showed that miR-762 is differentially expressed in immature and mature testes of Large White boars. Our present data shows that miR-762 directly binds the 3′ untranslated region (3′UTR) of ring finger protein 4 (RNF4) and down-regulates RNF4 expression. A single nucleotide polymorphism (SNP) in the RNF4 3′UTR that is significantly associated with porcine sperm quality traits leads to a change in the miR-762 binding ability. Moreover, miR-762 promotes the proliferation of and inhibits apoptosis in porcine immature Sertoli cells, partly by accelerating DNA damage repair and by reducing androgen receptor (AR) expression. Taken together, these findings suggest that miR-762 may play a role in pig spermatogenesis by regulating immature Sertoli cell growth.

The endocannabinoid system: A novel player in human placentation

Cannabis sativa is the most consumed illegal drug around the world. Its consumption during pregnancy is associated with gestational complications, particularly with fetal growth restriction. Endocannabinoids (eCBs) are lipid molecules that act by activating the G-protein coupled cannabinoid receptors, which are also target of the phytocannabinoid Δ(9)-tetrahydrocannabinol (THC). The endocannabinoid system (ECS) participates in distinct biological processes, including pain, inflammation, neuroprotection, and several reproductive events. In addition, an abnormal expression of ECS is associated with infertility and miscarriages. This manuscript will review and discuss the expression of ECS in normal and pathological human placentas, and the role of eCBs and THC in trophoblast proliferation, apoptosis, differentiation, and function. The current evidence points towards a role of ECS in human placentation, shedding light on the contribution of the eCBs in the coordination of human placentation, and in the cellular mechanisms underlying the deleterious effects of cannabis consumption during pregnancy.

Characterization of swine testicular cell line as immature porcine Sertoli cell line

Swine testicular (ST) cell line is isolated from swine fetal testes and has been widely used in biomedical research fields related to pig virus infection. However, the potential benefit and utilization of ST cells in boar reproductive studies has not been fully explored. As swine fetal testes mainly contain multiple types of cells such as Leydig cells, Sertoli cells, gonocytes, and peritubular myoid cells, it is necessary to clarify the cell type of ST cell line. In this study, we identified ST cell line was a collection of Sertoli cells by analyzing the unique morphological characteristic with satellite karyosomes and determining the protein expression of two markers (androgen-binding protein, ABP; Fas ligand, FASL) of Sertoli cells. Then ST cells were further confirmed to be immature Sertoli cells by examining the expression of three markers (anti-Mullerian hormone, AMH; keratin 18, KRT18; follicle-stimulating hormone receptor, FSHR). In conclusion, ST cells are a collection of immature Sertoli cells which can be good experimental materials for the researches involved in Sertoli cell functions and maturation, or even in boar reproductions.

Preferential epithelial expression of type-1 cannabinoid receptor (CB1R) in the developing canine embryo

The use of cannabinoid receptor agonists is gaining a strong interest both in human and veterinary medicine. The potential use of cannabimimetic compounds in companion animals was reviewed in 2007 for their role in tissue inflammation and pain. A better knowledge of type-1 cannabinoid receptor (CB1R) expression on the target population may help in risk management in order to prevent unwanted side effects. We used 30-days old canine embryos to describe the distribution of CB1R by means of immunohistochemistry with a commercially available antibody.CB1R immunoreactivity was mainly epithelial and included most structures of central and peripheral nervous system, inner ear, olfactory epithelium and related structures, eye and thyroid. Further investigative research on the role of the endocannabinoid system in the developmental biology field is needed, however, we show that in the canine species we must consider pregnancy as risk condition for developmental abnormalities that may arise upon the use of CB1R receptor agonists.

Effects of Heliopsis longipes ethanolic extract on mouse spermatozoa in vitro

CONTEXT

Heliopsis longipes (A. Gray) Blake (Asteraceae), a plant native to Mexico, is used in traditional medicine as analgesic and microbicide. The main component in the H. longipes ethanolic extract (HLEE) is affinin, as determined by HPLC/UV-visible and NMR measurement. To date, there is no documented evidence on the spermicidal activity of this extract.

OBJECTIVE

The objective of this study was to assess in vitro the effectiveness of HLEE as spermicide.

MATERIALS AND METHODS

The spermicidal activity of HLEE was evaluated by the Sander-Cramer assay. Spermatozoa were incubated for 20 s with HLEE in concentrations ranging from 75 to 2000 µg/mL to determine the minimum effective concentration (MEC) value. The 50% effective concentration (EC50) of HLEE was estimated by assaying serial dilutions from the MEC. Additionally, sperms were incubated with 125, 250, or 500 µg/mL of HLEE to evaluate the viability and the integrity of sperm membrane. Lipid peroxidation was assessed by the thiobarbituric acid reactive substances assay.

RESULTS

HLEE caused an inhibition of 100% in spermatozoa motility at a MEC value of 2000 µg/mL; the EC50 value was 125 µg/mL. Additionally, exposure to HLEE at 125, 250, or 500 µg/mL for 30 min decreased sperm viability to 27%, 8%, and 2% of the control value, respectively, and significantly increased the percentage of sperms with structurally disorganized membrane. HLEE also increased significantly the level of lipid peroxidation in sperms with respect to controls.

DISCUSSION AND CONCLUSION

The results demonstrate the spermicidal activity of HLEE in vitro and suggest that this action is caused by oxidative damage and alterations in the spermatozoal membrane.

The viability of mouse spermatogonial germ cells on a novel scaffold, containing human serum albumin and calcium phosphate nanoparticles

BACKGROUND

In spermatogenesis, spermatogonial cells differentiate to the haploid gametes. It has been shown that spermatogenesis can be done at in vitro condition. In vitro spermatogenesis may provide an open window to treat male infertility.

OBJECTIVE

The aim of this study was to evaluate the effects of a novel scaffold containing human serum albumin (HSA)/tri calcium phosphate nanoparticles (TCP NPs) on the mouse spermatogonial cell line (SCL).

MATERIALS AND METHODS

First, TCP NPs were synthesized by reaction of calcium nitrate and diammonium phosphate at pH 13. Then, serial concentrations of TCP NPs were separately added to 500 mg/mL HSA, and incubated in the 100(o)C water for 30 min. In the next step, each scaffold was cut (2×2mm), placed into sterile well of microplate, and then incubated for 1, 2, and 3 days at 37(o)C with mouse SCL. After incubation, the cytotoxicity of the scaffolds was evaluated by different tests including 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT) assay, lactate dehydrogenase (LDH) assay, vital staining, and cell counting. On the other hand, the release of TCP NPs and HSA from the scaffolds was measured.

RESULTS

Based on microscopic observation, the size of cavities for all scaffolds was near 200-500 µm, and the size of TCP NPs was near 50-100 nm. All toxicity tests showed that the increase of TCP concentration in the scaffold did not affect mouse SCL. It means that the percentage of cell viability, LDH release, vital cells, and cell quantity was 85%, 105%, 90%, and 110%, respectively. But, the increase of incubation time led to increase of LDH release (up to 115%) and cell count (up to 115%). Also, little decrease of cell viability and vital cells was seen when incubation time was increased. Here, no release of TCP NPs and HSA was seen after increase of TCP concentration and incubation time.

CONCLUSION

It can be concluded that the increase of TCP concentration in HSA/ TCP NPs scaffold does not lead to cytotoxicity. On the other hand, the increase of incubation time leads to increase of mouse SCL cell death. In this study, it was found that TCP NPs and HSA could not release from the scaffolds. In future, both proliferation and differentiation of mouse SCL on HSA/TCP NPs scaffold must be checked over more wide incubation times.

Endocannabinoids and Reproductive Events in Health and Disease

The lasting research on the endocannabinoid system (ECS) has now provided solid and convincing evidence that proves the detrimental effects of recreational drug abuse (a growing habit among teenagers) on fertility. Endocannabinoids (eCBs) affect reproductive events from gametogenesis to fertilization, from embryo implantation to the final outcome of pregnancy and, thus, they have been proposed as suitable biomarkers to predict the reproductive potential of male and female gametes in clinical practice. Novel tools for reproductive medicine are highly sought after, and here we report the latest findings on the impact of the ECS on fertility, demonstrating how basic research can be translated into new medical strategies.