Plasma Estradiol Concentrations Research Articles

Response of the hen ovary to eCG treatment: Insight into morphology and expression of genes related to steroidogenesis and vitellogenesis

The present study aimed to examine the effect of equine chorionic gonadotropin (eCG) treatment on the chicken ovarian folliculogenesis and steroidogenesis. The expression of vitellogenesis-related genes in the liver was also investigated. Laying hens were injected with 75 I.U./kg of body weight/0.2 mL of eCG, once a day for 7 successive days. On day 7 of the experiment hens, including control hens which were receiving vehicle, were euthanized. The liver and ovarian follicles were harvested. Blood was collected daily through the whole experiment. The eCG treatment resulted in the cessation of egg laying after 3 or 4 days. The eCG-treated hens had heavier ovaries with a higher number of yellowish and yellow follicles arranged in a non-hierarchical way in contrast to ovaries of control hens. Moreover, these birds had elevated plasma estradiol (E2) and testosterone (T) concentrations. The molar ratios of E2:progesterone (P4) and T:P4 were increased in chickens injected with eCG. Real-time polymerase chain reaction revealed changes in mRNA abundances of steroidogenesis-associated genes (StAR, CYP11A1, HSD3β, and CYP19A1) in ovarian follicles: white, yellowish, small yellow, and the largest yellow preovulatory (F3-F1) as well as VTG2, apoVLDL II, and gonadotropin receptors in the liver. In general, the abundances of gene transcripts were higher in eCG-treated hens than in control hens. Western blot analyses showed an elevated abundance of aromatase protein in the prehierarchical and small yellow follicles of eCG-treated hens. Unexpectedly, there was presence of both FSHR and LHCGR mRNA in the liver and the level of expression was shifted in eCG-treated hens. In summary, eCG treatment leads to disruption of the ovarian hierarchy with accompanying changes in circulating steroids and ovarian steroidogenesis.

Dietary n-3 PUFA augments pre-ovulatory follicle turnover and prolificacy in well-fed ewes

The present study evaluated the effect of dietary supplementation with n-3 polyunsaturated fatty acids (PUFA) on preovulatory follicle (POF) turnover, prolificacy, and endocrine and metabolic milieu in Malpura sheep. Fifty cyclic ewes with 3–3.5 body condition scores on a five-point scale were allocated equally to two groups (n = 25) following estrus synchronization and were supplemented with 0.6 mL/kg body weight of n-3 PUFA-rich fish oil (FO) or palm oil (PO) as control, for 60 d following an acclimatization period of 7 d. All ewes were mated with sexually active rams at the end of the supplementation period. On ultrasonographic ovarian scanning at the last fourth estrus, the mean number of POFs was 77.8% greater (P < 0.01) in FO ewes than in the PO ewes. The proportion of ewes with multiple ovulations two months after the beginning of supplementation was 56% in the FO group as compared to 8% in the PO group. The number of fetuses was 46% higher (P < 0.01) in the FO than in the PO ewes at d 45 of gestation. At lambing, the twinning percent in the FO ewes was three times greater than in the PO ewes (27.3 vs. 9.1%). Plasma cholesterol, estradiol, and insulin concentrations were lower (P < 0.01) in ewes fed with FO than those offered PO group at the end of the feeding period. It was concluded that the dietary supplementation of n-3 PUFA-rich FO in well-fed Malpura ewes improved the number of follicles and ovulation rate which led to an increased prolificacy, accompanied by a reduction of plasma cholesterols, estradiol, and insulin.

The Temporal Associations of B-Mode and Power-Doppler Ultrasonography, and Ovarian Steroid Changes of the Periovulatory Follicle and Corpus Luteum During Luteogenesis and Luteolysis in Jennies.

This study aimed to determine the associations between B-mode and Power-doppler ultrasonography and ovarian steroids of the periovulatory follicle and respective corpus luteum (CL) during luteogenesis and luteolysis in jennies. Twenty-four periovulatory follicles/estrus of correspondent one inter-ovulatory interval (n=12 jennies) were assessed in the study. B-mode ultrasonography and teasing were carried out once day until the detection of a periovulatory follicle (≥28 mm, uterine edema, and signs of estrus). Thereafter, jennies were monitored at 4-hour-intervals by B-mode and Power-doppler ultrasonography. Closer to ovulation, jennies were hourly checked. Each CL was checked daily from luteogenesis to luteolysis. Plasma concentrations of estradiol and progesterone were assessed daily with chemiluminescence immunoassay. Granulosa echogenicity and thickness increased from -36 hour to -1 hour before ovulation in 70% of follicles (P < .05) and were strongly associated with impending ovulation (r=0.80 and r=0.70, respectively). The follicular-wall blood flow increased from -72 to -24 hour pre-ovulation, while the estradiol concentration declined from 42 pg/mL by -72 hour to 31.6 pg/mL by 24 hour before ovulation (P < .05). The vascularization of the periovulatory follicle decreased from 62% (-36 hour) to 37% (-1 hour) before ovulation (P < .05). The CL vascularization and progesterone concentration gradually increased, reaching the peak at 11- and 10-day after the ovulation, respectively (P < .05). The CL vascularization started to decline 3 day before luteolysis, while progesterone concentrations started to drop 4 day before luteolysis (P < .05). In conclusion, the structural changes of the periovulatory follicle detected on B-mode and Power-doppler can be used to detect impending ovulation in donkeys; however, Power-doppler, but not B-mode ultrasonography, can be used to assess CL function in jennies.

Забруднювач довкілля бісфенол А порушує програмування статевої поведінки у жіночого потомства щурів

Bisphenol A (BPA) is a common environmental pollutant and, due to its estrogenic properties, can cause disorders of the reproductive and other physiological systems of the body, especially in males. It is known that in male rats it disrupts the sexual differentiation of the brain (SDB) of the fetus in utero. Studies of the effects of perinatal exposure of fetuses and newborn females through the mother’s body under the conditions of long-term administration of BPA during pregnancy and lactation did not reveal significant changes in SDB. Identification of long-term endocrine, neuromorphological, and behavioral consequences of exposure of female rat fetuses to a low dose of BPA administered to mothers during the last week of pregnancy, which corresponds to the temporal period of SDB, was the aim of this study. Rats were orally administered BPA suspended in Dorfman gel at a daily dose of 25 μg/kg b.w., which is 200 times less than the NOAEL (no observed adverse effect level) for rats, via a gavage, or, as a positive control, estradiol diacetate (E2D) subcutaneously at a dose of 10 μg/kg b.w., during 15-21 days of pregnancy. Control animals received gel without BPA. The levels of estradiol, testosterone, and corticosterone in blood plasma, the response of the hypothalamic-pituitary-adrenal (HPA) axis to acute immobilization stress, sexual behavior, and the histological structure and karyometric parameters of neurocytes of the medial-preoptic nuclei (MPN) of the hypothalamus were studied in adult female offspring. Prenatal exposure to BPA or E2D decreased the concentration of estradiol in the blood plasma, while the levels of testosterone and corticosterone remained normal. In the females of the BPA and E2D groups, a masculinization of sexual behavior (mounting to a receptive female, approaching her, etc.) was observed, which, according to the number of lordosis reactions in the presence of a sexually experienced male, not accompanied by her defeminization. Changes in the morphology of the MPN, which belongs to the sex-dimorphic area of the brain, conformed to the masculinization of female sexual behavior due to prenatal exposure to a low dose of BPA. Karyometry of neurocytes of the hypothalamic MPN of rats revealed no difference between the control and the BPA group. The response of the HPA axis to immobilization stress did not change in both experimental groups. It is found for the first time that maternal exposure of in utero female rat fetuses to an ultra-low relative to the NOAEL dose of BPA during the last gestational week, which corresponds to the critical period of SDB impairs programming of sexual behavior in the direction of its masculinization and causes hypoestrogenemia at adulthood. Disorders of sexual behavior conformed to morphological changes of the hypothalamic MPN. The unidirectionality of functional disorders induced by prenatal exposure to BPA and the reference estrogenic drug E2D indicates that they are caused by the estrogenic properties of both substances.

The impact of FSH stimulation and age on the ovarian and uterine traits and histomorphometry of prepubertal gilts

This study investigated the effect of age and follicle stimulating hormone (FSH) treatment on the estradiol (E2) plasma concentration, ovarian follicle development, endometrial histomorphometry, and ultrasonographic parameters of the ovaries and uterus in prepubertal gilts. Thirty-five prepubertal gilts were grouped according to age (140 or 160 d), and within each age, gilts were allotted to receive 100 mg of FSH (treated; G140 + FSH [n = 10] and G160 + FSH [n = 7]) or saline solution (control; G140 + control [n = 10] and G160 + control [n = 8]). The total dose of FSH was divided into 6 similar doses administered every 8 h (days 0–2). Before and after FSH treatment, blood sample was collected, and transabdominal scanning of the ovaries and uterus was performed. Twenty-four hours after the last FSH injection, the gilts were slaughtered and their ovaries and uterus were processed for histological and histomorphometric analysis. The histomorphometric parameters of the uterus differed (P < 0.05) between prepubertal gilts at 160 d and 140 d of age. Moreover, changes (P < 0.05) in uterine and ovarian ultrasound images occurred between 140 and 160 d of age. Age and FSH treatment did not affect (P > 0.05) E2 plasma concentrations. Follicle stimulating hormone treatment did not affect (P > 0.05) the early stage of folliculogenesis in the prepubertal gilts; however, the number of early atretic follicles decreased (P < 0.05) after the FSH treatment. Follicle stimulating hormone administration increased (P < 0.05) the number of medium follicles and decreased (P < 0.05) the number of small follicles in 140 and 160 d old gilts. In the endometrium, luminal/glandular epithelium height and glandular diameter increased (P < 0.05) after FSH treatment. Thus, injections of 100 mg of FSH stimulate the endometrium epithelium and induce follicular growth to a medium follicle size without affecting the preantral stages in prepubertal gilts; also, the uterine macroscopic morphometry does not change from 140 to 160 d of age.

Synthetic microfiber exposure negatively affects reproductive parameters in male medaka (Oryzias latipes)

Microplastics not only accumulate in the bodies of fishes and cause damage to the organs, but also cause many other problems, such as reduced reproductive capacity, by acting directly or indirectly on the hypothalamus-pituitary-gonad axis (HPG axis). In this study, we investigated the changes in HPG axis-related genes in male medaka (Oryzias latipes) exposed to fiber-type microplastics. We confirmed the progression of vitellogenesis, a sign of endocrine disruption, in male fish. In the microfiber-exposed group, microfiber accumulation was confirmed in the gills and intestines. One week after exposure to two different concentrations of microfibers (500 and 1,000 fibers/L), the fish showed increased expression of gonadotropin-releasing hormone (GnRH) and luteinizing hormone receptor (LH-R) mRNA. From day 10 of exposure to the microfibers, there was an increase in the expression of the gonadotropin-inhibitory hormone (GnIH) mRNA and a decrease in the expression of GnRH and LH-R mRNA. There was an increase in the cytochrome P450 aromatase (CYP19a) mRNA expression and plasma estradiol (E2) concentration in the 1,000 fibers/L exposure group. High vitellogenin (VTG) mRNA expression was confirmed seven days after exposure in the 1,000 fibers/L group, which was consistent with the VTG mRNA expression signals detected in the liver using in situ hybridization. These results suggest that microfiber ingestion may cause short-term endocrinal disruption of the HPG axis in male medaka, which in turn may interfere with their normal maturation process.

Sleep-related factors and circulating levels of sex hormones in premenopausal Japanese women.

Sleep disruption and circadian disruption have been proposed to be risk factors of breast cancer. The present study examined the associations of sleep-related factors, referring to night shift work, sleep habits, and sleep disturbances, with the plasma levels of sex hormones in premenopausal Japanese women. Study participants were 432 women who had regular menstrual cycles less than 40 days long. Information on their history of night shift work and sleep disturbances was obtained using a self-administered questionnaire. Information on their sleep habits, such as usual wake-up times, bedtimes, and ambient light level while sleeping, was obtained in an interview. The participants' height and weight were measured. Plasma concentrations of estradiol, testosterone, dehydroepiandrosterone sulfate, sex hormone-binding globulin (SHBG), FSH, and LH were also measured. After controlling for the phase of the menstrual cycle and other covariates, more years of night shift work ≥ once a week during the past 10 years was significantly associated with a lower SHBG and a higher free estradiol level. Shorter sleep duration was significantly associated with the higher total, bioavailable, and free testosterone levels. Sleep disturbance by awaking after sleep onset was significantly associated with a high free estradiol level. The data suggest that long-term night shift work, short sleep duration, and arousal during sleep are associated with higher estradiol or testosterone levels in premenopausal women.

Blood hormone concentrations as markers and predictors of porcine meat production and quality?

Context The applicability of hormones in the prediction of meat production in non-ruminant species has been poorly examined. Aims To examine the applicability of plasma concentrations of leptin, estradiol, progesterone and insulin-like growth-factor I (IGF-I) for characterisation and early prediction of the production and quality of meat in gilts. Methods Animals were compared at 150 days of age with below (‘low’) and above (‘high’) median hormone concentrations and their traits of meat production and quality at the age of 200 days. Key results Animals with a high leptin concentration in blood at the age of 150 days had higher slaughter and carcass weights and weight of ham, but a lower lean meat content at the age of 200 days, than did the gilts with a low leptin concentration. Animals with a high estradiol concentration had a higher carcass weight, weight of ham and backfat thickness and a lower electrical conductivity of musculus semimembranosus than did animals with a low estradiol concentration. High blood IGF-I concentration was associated with a higher slaughter weight, carcass weight and lean meat content. No significant differences between the animals with ‘high’ and ‘low’ progesterone concentration and meat characteristics have been found. Conclusions These observations confirm the involvement of leptin, IGF-I and estradiol in up-regulation of meat production in pigs. Furthermore, they suggest that leptin can be useful for characterisation and prediction of fat production, whereas IGF-I and estradiol (but not progesterone) could be both markers and predictors of porcine growth and meat production. Implications The blood concentrations of these hormones could help in characterisation and selection of pigs for meat production.

Intrauterine LPS inhibited arcuate Kiss1 expression, LH pulses, and ovarian function in rats.

Uterine inflammatory diseases are a major cause of infertility in humans and domestic animals. The current findings that intrauterine lipopolysaccharide is absorbed in systemic circulation and attenuates ovarian cyclic activities could provide a basis for developing novel treatments to improve fertility. Uterine inflammatory diseases are a major cause of infertility in humans and domestic animals. Circulating lipopolysaccharide (LPS), a bacterial endotoxin causing uterine inflammation, reportedly downregulates the hypothalamic-pituitary-gonadal axis to mediate ovarian dysfunction. In contrast, the mechanism whereby intrauterine LPS affects ovarian function has not been fully clarified. This study aimed to elucidate whether uterine exposure to LPS downregulates hypothalamic kisspeptin gene (Kiss1) expression, gonadotropin release, and ovarian function. Uterine inflammation was induced by intrauterine LPS administration to ovary-intact and ovariectomized female rats. As a result, plasma LPS concentrations were substantially higher in control rats until 48 h post injection, and the estrous cyclicity was disrupted with a prolonged diestrous phase. Three days post injection, the number of Graafian follicles and plasma estradiol concentration were reduced in LPS-treated rats, while numbers of Kiss1-expressing cells in the anteroventral periventricular nucleus and arcuate nucleus (ARC) were comparable in ovary-intact rats. Four days post injection, ovulation rate and plasma progesterone levels reduced significantly while gene expression of interleukin1β and tumor necrosis factor α was upregulated in the ovaries of LPS-treated rats that failed to ovulate. Furthermore, the number of Kiss1-expressing cells in the ARC and pulsatile luteinizing hormone (LH) release were significantly reduced in ovariectomized rats 24 h post injection. In conclusion, these results indicate that intrauterine LPS is absorbed in systemic circulation and attenuates ovarian function. This detrimental effect might be caused, at least partly, by the inhibition of ARC Kiss1 expression and LH pulses along with an induction of ovarian inflammatory response.

The function of the pituitary-testicular axis in dogs prior to and following surgical or chemical castration with the GnRH-agonist deslorelin.

Chemical castration, that is the reduction of circulating testosterone concentrations to castrate levels by administration of a GnRH-agonist implant, is a popular alternative to surgical castration in male dogs. Detailed information concerning the pituitary-testicular axis following administration of a GnRH-agonist implant is still scarce. Therefore, GnRH-stimulation tests were performed in male dogs, prior to and after surgical and chemical castration. This approach also allowed us to determine plasma concentrations of testosterone and oestradiol in intact male dogs for future reference and to directly compare the effects of surgical and chemical castration on the pituitary-testicular axis. In intact male dogs (n=42) of different breeds GnRH administration induced increased plasma LH, FSH, oestradiol and testosterone concentrations. After surgical castration basal and GnRH-induced plasma FSH and LH concentrations increased pronouncedly. Additionally, basal and GnRH-induced plasma oestradiol and testosterone concentrations decreased after surgical castration. After chemical castration, with a slow-release implant containing the GnRH-agonist deslorelin, plasma LH and FSH concentrations were lower than prior to castration and lower compared with the same interval after surgical castration. Consequently, plasma oestradiol and testosterone concentrations were lowered to values similar to those after surgical castration. GnRH administration to the chemically castrated male dogs induced a significant increase in the plasma concentrations of LH, but not of FSH. In conclusion, after administration of the deslorelin implant, the plasma concentrations of oestradiol and testosterone did not differ significantly from the surgically castrated animals. After GnRH-stimulation, none of the dogs went to pre-treatment testosterone levels. However, at the moment of assessment at 4,4 months (mean 133 days ± SEM 4 days), the pituitary gonadotrophs were responsive to GnRH in implanted dogs. The increase of LH, but not of FSH, following GnRH administration indicates a differential regulation of the release of these gonadotrophins, which needs to be considered when GnRH-stimulation tests are performed in implanted dogs.

Physiological interindividual variability in endogenous estradiol concentration does not influence adipose tissue and hepatic lipid kinetics in women.

Increased triglyceride (TG) and apolipoprotein B-100 (apoB-100) concentrations in plasma are important risk factors for cardiovascular disease in women. Administration of some estrogen preparations raises plasma TG and apoB-100 concentrations by increasing hepatic very low-density lipoprotein (VLDL) TG and apoB-100 secretion rates. However, the influence of physiological variation in endogenous estradiol on VLDL-TG and VLDL-apoB-100 metabolism and on free fatty acid (FFA) release into plasma (the major source of fatty acids for VLDL-TG production) is not known. We measured basal VLDL-TG, VLDL-apoB-100, and plasma FFA kinetics by using stable isotopically labeled tracers in 36 eumenorrheic, premenopausal women (age: 33 ± 2 years, BMI: 31 ± 1 kg/m2; mean ± s.e.m.) during the follicular phase of the menstrual cycle; participants were divided into two groups based on low (n = 18) or high (n = 18) plasma estradiol concentrations (defined as below or above the median value of 140 pmol/L in the whole group). Mean plasma estradiol concentration was >3-fold higher in the high-estradiol than in the low-estradiol group (299 ± 37 and 96 ± 7 pmol/L, P < 0.001); there was no difference in plasma progesterone concentrations between the two groups (P = 0.976). There were no significant differences in plasma FFA concentration, FFA rate of appearance in plasma, VLDL-TG and VLDL-apoB-100 concentrations, hepatic VLDL-TG and VLDL-apoB-100 secretion rates, VLDL-TG and VLDL-apoB-100 plasma clearance rates, and mean residence times (all P ≥ 0.45). No significant associations were found between plasma estradiol concentration and FFA, VLDL-TG, and VLDL-apoB-100 concentrations and kinetics (all P > 0.19). Plasma estradiol concentration is not an important correlate of basal plasma FFA, VLDL-TG, and VLDL-apoB-100 kinetics in premenopausal women.

Bisphenol S Alters the Steroidome in the Preovulatory Follicle, Oviduct Fluid and Plasma in Ewes With Contrasted Metabolic Status.

Bisphenol A (BPA), a plasticizer and endocrine disruptor, has been substituted by bisphenol S (BPS), a structural analogue that had already shown adverse effects on granulosa cell steroidogenesis. The objective of this study was to assess the effect of chronic exposure to BPS, a possible endocrine disruptor, on steroid hormones in the ovary, oviduct and plasma using the ewe as a model. Given the interaction between steroidogenesis and the metabolic status, the BPS effect was tested according to two diet groups. Eighty adult ewes were allotted to restricted (R) and well-fed (WF) groups, that were further subdivided into two subgroups. Ewes were exposed to 50 µg BPS/kg/day in their diet (R50 and WF50 groups) or were unexposed controls (R0 and WF0 groups). After at least 3 months of BPS exposure, preovulatory follicular fluid, oviduct fluid and plasma were collected and steroid hormones were analyzed by gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). A deleterious effect of restricted diet on the volume of oviduct fluid and numbers of pre-ovulatory follicles was observed. Exposure to BPS impaired estradiol concentrations in both follicular and oviduct fluids of well-fed ewes and progesterone, estradiol and estrone concentrations in plasma of restricted ewes. In addition, a significant interaction between metabolic status and BPS exposure was observed for seven steroids, including estradiol. In conclusion, BPS acts in ewes as an endocrine disruptor with differential actions according to metabolic status.

Endocrine disrupting effects induced by levonorgestrel linked to altered DNA methylation in rare minnow (Gobiocypris rarus)

Progestins are worldwide environmental contaminants, however, their ecotoxicological risks and underlying molecular mechanisms of effects are not fully understood. In this study, newly hatched rare minnow (Gobiocypris rarus) larvae were exposed to environmentally realistic concentrations (1 and 10 ng/L) of levonorgestrel (LNG) for 6 months. The sex ratios were not affected by LNG at both concentrations, but the growth was significantly inhibited at 10 ng/L while promoted at 1 ng/L. Histological analysis revealed impaired gonadal development. Plasma concentrations of estradiol in females and testosterone in both sexes were significantly induced after exposure to 1 ng/L LNG; plasma concentrations of 11-ketotestosterone were markedly increased in females exposed to 10 ng/L LNG and in males exposed to both concentrations of LNG. The transcription of cyp19a1a was significantly up-regulated in ovaries exposed to LNG at both concentrations, while cyp17a1 was down-regulated in testes exposed to 10 ng/L LNG. The global DNA methylation level was significantly decreased in testes exposed to 10 ng/L LNG, which might be associated with inhibited spermatogenesis. Gender-specific changes in CpG methylation patterns were induced by LNG in the 5′ flanking region of cyp19a1a, with hypomethylation in ovaries but hypermethylation in testes, which was linked to the regulation of cyp19a1a transcription. The results suggest that LNG could induce endocrine disrupting effects in fish at environmentally realistic concentrations, which may be linked to altered DNA methylation. This study indicates potentially high ecological risk of LNG to fish populations, and warrants researches on regulatory mechanisms of epigenetic modifications in progestin-induced effects.

Comparison of GnRH and hCG effects on oestradiol, progesterone and premature luteolysis in Ovsynch-synchronized ewes.

The purpose of this study was to ascertain whether premature luteolysis can be alleviated by substituting the ovulation inducing agent hCG for GnRH. Seventy-two hours after the end of artificial insemination (AI), pluriparous Awassi ewes were randomly assigned to one of three treatment groups of 13 ewes each. First group received 37.5µg of the GnRH analog Lecirelin, the second 1000I.U hCG and the third group served as a control (received 1ml of physiological saline solution). Blood samples were collected at daily intervals after GnRH treatment and analysed for plasma oestradiol and progesterone concentrations. Ovarian follicles were monitored ultrasonically at the time of GnRH administration, 60hr and 84hr later. Pregnancy was diagnosed ultrasonically at Day 35 after AI. Number and size of ovarian follicles did not differ (p>.05) among treatment groups. Onset and duration of oestrus were not affected by treatment (p>.05). No significant differences (p>.05) were recorded in oestradiol and progesterone concentrations between the treatment groups during the inspection period. Premature luteolysis became evident in ewes with longer oestrous durations by Day 6.25 after AI and amounted to 7.69%, 18.18% and 23.07% in GnRH, hCG and Control groups respectively. Pregnancy rates increased to 92.31% and 81.82% in GnRH and hCG groups, compared to 76.92% in the Control group. The results indicate that GnRH was more effective in reducing premature luteolysis than hCG. Substituting hCG for GnRH as an ovulation inducing agent was of no avail.

Chronic exposure to sublethal concentrations of saxitoxin reduces antioxidant activity and immunity in zebrafish but does not affect reproductive parameters

Saxitoxin produced by dinoflagellates and cyanobacteria can be transferred to humans through intoxicated organisms such as fish, but limited research has addressed the adverse effects of this toxin on aquatic organisms. In this study, we measured the potential effects of a 90-day exposure to saxitoxin (0.1 or 1 µg·L - 1) on body weight and length, antioxidant defense system, immunity, sex hormones, and genes involved in associated key metabolic pathways in zebrafish (Danio rerio). Significant impairments in body weight and length were observed in response to 1 µg·L - 1 saxitoxin in both male and female zebrafish. A significant increase in the levels of malondialdehyde, together with decreased enzymatic activities of catalase and superoxide dismutase, was observed in fish of both sexes exposed to 1 µg·L - 1 saxitoxin, indicating the occurrence of lipid peroxidation and oxidative stress. Immune parameters such as alternative complement activity, lysozyme activity, and immunoglobulin content were also significantly reduced. However, exposure of male and female zebrafish to saxitoxin for 90 days did not significantly affect reproductive parameters such as the gonadosomatic index and plasma concentrations of vitellogenin, estradiol, and 11-keto testosterone. Transcriptional responses showed similar trends to those of the biochemical parameters, as genes involved in the antioxidant defense system and immunity were downregulated, whereas the transcription of genes related to reproductive metabolism showed no significant change upon treatment with 1 µg·L - 1 saxitoxin. Our findings indicate that long-term exposure to a sublethal concentration of saxitoxin can inhibit growth through induction of oxidative stress and immunosuppression, while the reproductive parameters of zebrafish are not a main target of this toxin at sublethal concentrations.

Effect of the concentration of estradiol and vitellogenin in the blood serum of meat and egg breed chickens on egg productivity

The aim of the research is to determine the effect of changes in the concentration of estradiol-17β on the concentration of vitellogenin at the stage of egg shell formation and preparation of the body of meat and egg breed chickens (for example, the Pushkin breed) for ovulation.Materials and methods. The material for the study was the Pushkin breed chickens, in the amount of 28 heads. at the age of 48 weeks. Chickens were kept in individual cages. Light mode - 14C:10T. Drinking - nipple, temperature in the house and feeding - according to the standards adopted in the bioresource collection of RRIFAGB "Genetic collection of rare and endangered chicken breeds." Within 10 days prior to blood sampling, an ultrasound scan of the ovary and oviduct was performed from the studied group of chickens, which made it possible to determine the stage of egg formation. Blood from the studied chickens was taken in the morning on an empty stomach for the simultaneous determination of the concentration of estradiol and vitellogenin at the stage of egg shell formation. The concentration of estradiol and vitellogenin in the blood plasma of chickens was determined by ELISA. To clarify the effect of the concentration of estradiol (E2) on vitellogenin (VTG), the studied flock was divided into 2 groups according to the concentration of vitellogenin: 1st gr. – &gt; Mav. (&gt; 20 μg / ml) and 2nd gr. – &lt; Mav. (&lt;20 μg / ml). During the study period, eggs of chickens were evaluated according to the following morphometric parameters: the weight of the egg, yolk, protein and shell, elastic deformation, shape index, density of protein fractions, thickness of the shell and subshell, marbling. The number of eggs laid was determined in 10-day trial period.Results. It has been established that the duration of the ovulatory cycle in Pushkin breed chickens is 27-29 hours. As a result of such a long ovulatory cycle in the following days, laying of eggs occurs later with a progressive shift, as a result of which the laying cycle on average for the studied group of chickens is 3 days. The E2 level in the 1st group was 258,48 ± 30,60 pg/ml (p &lt; 0,05), which significantly differed from the 2nd group – 181,45 ± 13,81 pg/ml. A positive correlation was found between VTG and E2, r = 0,5 (p &lt; 0,001).Conclusion. The VTG level significantly increases in Pushkin chickens at the age of 48 weeks with an increase in the concentration of E2 in the blood. A positive correlation was noted between these features. According to the results of our research, the high content of estradiol and vitellogenin in the chickens blood serum did not have a significant effect on egg productivity.

Biochemical Changes During the First Year of Feminizing Hormone Therapy in Transfeminine Individuals.

BackgroundPersons with assigned male sex at birth (AMAB) might wish to obtain feminization and/or demasculinization according to the person's gender identity and are therefore treated with estradiol and/or antiandrogens.AimThe aim was to evaluate biochemical changes and side effects in AMAB individuals treated with guideline-based feminizing hormone treatment (FHT).MethodsMedical charts of 99 AMAB individuals ≥ 18 years referred to the Center for Gender Identity; Aalborg University hospital, Denmark, between January 2017 and July 2019 were reviewed to identify adverse side effects. Furthermore, data from the laboratory information system (Labka II) were retrieved to obtain biochemical parameters. Biochemical plasma concentrations after initiation of FHT were compared to concentrations prior to FHT and to existing guidelines.OutcomesAfter 11–19 months, 29% of the trans feminine individuals had plasma estradiol concentrations within the treatment target.ResultsThe plasma concentration of estradiol varies greatly during FHT. Plasma levels of estrogen were within the treatment target after 11–19 months of treatment, whereas 100% had concentrations within the reference range for premenopausal cis-women. Furthermore, plasma concentrations of lipids and hematological parameters approached female reference ranges after 11 months of FHT.Clinical ImplicationsThe target levels of plasma estradiol concentrations during FHT could be expanded, making the wanted physiological changes easier to obtain.Strengths & LimitationThis cohort study included 99 AMAB individuals and biochemical evaluation was possible in 67 individuals. Only one individual was lost during follow-up. However, the follow-up period was limited making evaluation of long-term side effects impossible.ConclusionPlasma concentration of estradiol varies greatly during guideline based FHT, making plasma estradiol levels within the target level difficult to attain.JA Hojbjerg, AD Højgaard, A-M Hvas. Biochemical Changes During the First Year of Feminizing Hormone Therapy in Transfeminine Individuals. Sex Med 2021;10:100472.

Ultrasonographic examination of equine fetal growth parameters throughout gestation in pony for Equine-Assisted Therapy.

Equine-Assisted Therapy (EAT) is gaining popularity. Ultrasound examination is used to decrease the abortion rate in horses. In this study, to monitor fetal well-being throughout the gestation for EAT, we measured fetal heart rate (FHR), fetal eye orbit (FEO), fetal gonad length (FGL), fetal kidney length (FKL), and the combined thickness of the uterus and placenta (CTUP) by ultrasonography in pony mares. Additionally, we measured the plasma progesterone (P4) and estradiol (E2) concentrations in pregnant horses using enzyme immunoassay. The FGL peaked at week 32 and then decreased to term, and a strong correlation (r=0.72, P<0.001) between the FGL and E2 concentration was observed. A strong correlation with gestational age was detected among the FEO (r=0.96, P<0.001), FKL (r=0.85, P<0.001), and CTUP (r=0.96, P<0.001). The P4 concentration peaked at week 10, decreased to low levels (below 5 ng/ml), and peaked before parturition. In conclusion, this study provides information on fetal growth throughout gestation in pony mares for EAT. In addition, it revealed the relationship between ultrasonographic profile and plasma hormone concentrations during gestation.

Chronic Dietary Exposure of Roosters to a Glyphosate-Based Herbicide Increases Seminal Plasma Glyphosate and AMPA Concentrations, Alters Sperm Parameters, and Induces Metabolic Disorders in the Progeny.

The effects of chronic dietary Roundup (RU) exposure on rooster sperm parameters, fertility, and offspring are unknown. We investigated the effects of chronic RU dietary exposure (46.8 mg kg−1 day−1 glyphosate) for 5 weeks in 32-week-old roosters (n = 5 RU-exposed and n = 5 control (CT)). Although the concentrations of glyphosate and its main metabolite AMPA (aminomethylphosphonic acid) increased in blood plasma and seminal fluid during exposure, no significant differences in testis weight and sperm concentrations were observed between RU and CT roosters. However, sperm motility was significantly reduced, associated with decreased calcium and ATP concentrations in RU spermatozoa. Plasma testosterone and oestradiol concentrations increased in RU roosters. These negative effects ceased 14 days after RU removal from the diet. Epigenetic analysis showed a global DNA hypomethylation in RU roosters. After artificial insemination of hens (n = 40) with sperm from CT or RU roosters, eggs were collected and artificially incubated. Embryo viability did not differ, but chicks from RU roosters (n = 118) had a higher food consumption, body weight and subcutaneous adipose tissue content. Chronic dietary RU exposure in roosters reduces sperm motility and increases plasma testosterone levels, growth performance, and fattening in offspring.

Randomized, double-blind, two-way crossover bioequivalence and adhesion study, in healthy women, of a transdermal contraceptive patch with a newly sourced adhesive component at the end of shelf life vs. the EVRA patch at the beginning of shelf life.

Objective: Evaluate bioequivalence, based on norelgestromin (NGMN) and ethinyl estradiol (EE) plasma concentrations, and adhesion of a transdermal contraceptive patch containing a newly sourced adhesive component (test) at end of shelf life (EOSL) vs. the marketed EVRA patch (reference) at beginning of shelf life (BOSL). Materials and methods: In this randomized, double-blind, two-way crossover study, healthy women received a single, 7-day application of test and reference patches in 4 sequences: two 11-day treatment periods separated by a 21-day washout. Assessments included NGMN and EE pharmacokinetics (PK), adhesion (per European Medicines Agency (EMA) 5-point scale), irritation potential and application-site reactions, and tolerability. Patches were bioequivalent if 90% CIs of geometric mean ratios (GMRs) of test/reference for Cmax, AUC168h, AUC0–tlast, and AUC∞ were 80 – 125%. Patch adhesion was comparable if ratios of geometric mean cumulative adhesion percentages were ≥ 90%. Results: 68 women were randomized, and 62 completed both treatments. 55 and 59 participants in the reference and test group, respectively, had patch adhesion ≥ 80% (EMA score 0 – 1) at end of treatment. Bioequivalence was demonstrated: GMRs for pharmacokinetic (PK) parameters ranged from 102.76 to 105.57% for NGMN and 93.78 – 94.80% for EE, and associated 90% CIs were fully within the bioequivalence acceptance range (80 – 125%) for both. The patches had comparable adhesion properties (GMR, 101.4% (90% CI: 99.2 – 103.6)) and incidences of treatment-emergent adverse events. Conclusion: NGMN-EE transdermal test patch at EOSL was bioequivalent to the marketed patch at BOSL, supporting widening the product’s shelf-life specification. Adhesive properties and safety profiles were comparable between patches.