Duration Of Estrous Cycle Research Articles

Icariin, A Novel Promising Complementary Therapeutic Strategy in the Management of Female Infertility: A Literature Review:.

The prevalence of pre-menopausal female infertility is increasing considerably due to various causes such as environmental pollutants, increased administration of chemotherapeutics and radiation exposure, microbial infections, and genetic/epigenetic alterations. However, the current therapeutical strategies remain unfavorite as the disadvantages are strongly challenging. Icariin (ICI) is a phytoestrogen that exerts some promising properties in order to alleviate female infertility. Therefore, the current literature review aimed to evaluate the conducted studies regarding the beneficial impacts of ICI on the female reproductive system and female fecundity. The findings of the present study revealed that ICI is able to modulate the levels of reproductive hormones as it causes a significant decrement in the levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) while increasing the levels of estrogen and progesterone. Furthermore, the administration of ICI results in a dramatic alteration in the expression of sex steroids’ receptors, particularly in female reproductive tissues. In addition, preserving ovarian follicular reserve, improving the ovarian and uterine histoarchitecture, elongating the estrous cycle duration, and eventually advancing the female fecundity are other major effects of ICI on the female reproductive system. Despite these desired beneficial properties, the current knowledge appears to be insufficient, hence further investigations, particularly on humans, are encouraged. To the best of our knowledge, this review provides a comprehensive information regarding the beneficial effects of Icariin on female infertility for the firs time.

Seasonal distribution of repeat breeder cows and evaluation of modified protocols for post AI treatment during summer.

An important problem of dairy industry worldwide is repeat breeder cows (RB). In this study, one farm in Northern Greece was chosen on the basis of subfertility. First, the available reproductive data of the previous year were evaluated; then, the farmer was advised to use the most common treatments for RB [GnRH with the third artificial insemination (AI+GnRH) or ovsynch in cows found empty after the second AI], and their efficacy was monitored throughout the year. Cows (n = 147) 2.5 to 4.5 years old were included. During the next year, post AI treatments (meta-ovsynch and meta-AI) were used during summer; GnRH (100 μg of gonadorelin) alone or in combination with meloxicam (0.5 mg/kg BW) was used during summer. Meta-ovsynch protocols were administered to 29 cows detected as non-pregnant after 3 AIs; cows were divided randomly into 3 meta-ovsynch (OS) groups: group OS (controls, n = 10), standard ovsynch protocol; group OS+GnRH (n = 10), OS plus GnRH 10 days after AI; and group OS+GnRH+NSAID (n = 9), OS plus GnRH 10 days after AI plus meloxicam 15 days after AI. Meta-AI protocols were tested in 27 RB cows; cows were divided randomly into 3 AI groups: GnRH (n = 9), 1 dose of GnRH with AI; GnRH-GnRH (n = 9), two doses of GnRH, one with AI and another 10 days later; and GnRH-GnRH-NSAID (n = 9), two doses of GnRH as in GnRH-GnRH group and one dose of meloxicam 15 days after AI. Pregnancy diagnosis was performed by ultrasound 38 days after AI. During the 1st year of evaluation, 53.79% of cows had received ≥ 3 AIs; the highest percentage (38.48%) of RB cows was recorded during autumn. After treatment for RB, the lowest (P < 0.05) pregnancy rate (PR) was recorded in August (18.18%) compared to January (75.0%), May (53.33%), and December (50.0%, P < 0.1). The efficacy of ovsynch during winter was significantly higher compared to all the other seasons. The percentage of cows with increased estrous cycle duration (24-37 days) after RB treatment and AI was the highest (P < 0.05) in spring and summer after AI+GnRH and the lowest (P < 0.05) during winter after ovsynch. Concerning the post AI treatments during summer, significantly higher pregnancy rate was recorded in the OS+GnRH+NSAID group (55.55%) compared to OS+GnRH (10%) and OS (10%) groups. Pregnancy rates did not differ among AI groups. It seems that OS+GnRH+NSAID is a promising protocol for RB cows during summer although further research is needed to support the present results.

Toxic effect of Syzygium guineense ethanolic extract on female reproduction in rats: An evidence from a 10 week repeated-dose toxicity study

IntroductionIt has been reported that some herbal products affect reproduction. To date, reproductive toxicity of Syzygium guineense has not been investigated although the plant is widely used in treating fertility related problems. Thus, the objective of the current study was to investigate the toxic effects of 70% ethanol extract of S. guineense leaves on the reproductive function and histopathology of reproductive organs in female rats. MethodsEighty female Wistar albino rats were randomly divided into four groups where each group consisted of 20 rats. Rats in the first three groups were treated with S. guineense extract at doses of 250, 500 and 1000 mg/kg body weight, respectively. The fourth group served as a control group. The rats were treated for ten consecutive weeks. The length of estrous cycle, reproductive indices, pregnancy outcomes, and number of postnatal deaths were recorded. At necropsy, organ weight was measured, gross and histopathological examinations of ovaries, uterus, and vagina were conducted. ResultsTreatment of rats, with high dose (1000 mg/kg) of S. guineense, significantly prolonged the duration of estrous cycle and reduced weight of uterus and ovaries as well as the number of total and live birth pups. However, there were no significant changes observed in reproductive indices and gross morphology as well as histopathology of ovaries, uterus, and vagina. ConclusionAdministration of high doses of S. guineense could be toxic to some aspects of the reproductive system of female rats and might also affect reproduction. Therefore, consuming high dose of S. guineense leaves is not recommended.

EFFECT OF BABESIA BIGEMINA AND THEILERIA ANNULATA ON WEIGHT GAIN, MILK YIELD AND ESTROUS CYCLE IN EXPERIMENTALLY INFECTED BOS TAURUS AND BUBALUS BUBALIS

In Pakistan, buffaloes and cattle are the main source for the milk and meat production ultimately having a great economic impact on the socio-economic living of the people. It is believed that blood protozoan parasitic diseases like Babesiosis and Theileriosis caused by tick-borne blood parasite greatly reduce the productivity of the animals. Hence, the study was designed to assessthe effect of Babesia bigemina and Theileria annulata infection on the body weight, estrous cycle and milk production in cattle and buffaloes. Two hundred animals comprising of Bubalus bubalis and Bos taurus (Holstein Friesian, Jersy and Sahiwal) adults and calves were selected for this study. A significant decrease was observed in weight of the affected animals. Delayed maturity was also seen in calves affected with Theileriosis as compared with the control group of calves as the animals gained weight at slower rate after recovery from the disease. Production of milk in control group of Bos taurus and Bubalis bubalis was 14.6 ± 0.23Kg, 13.3 ± 0.2Kg, 11.5 ± 0.4Kg and 12.0 ± 0.31Kg whereas milk production in Babesia affected groups declined to 4.7 ± 0.02Kg, 6.1 ± 0.5Kg, 4.3 ± 0.3Kg and 4.3 ± 0.24Kg respectively. Milk production in control groups of animals of Bos was 13.3 ± 0.2Kg, 14.6 ±0.23Kg and 11.5±0.4Kg whereas milk yield in Theileriosis affected groups decreased to 5.6 ± 0.37Kg, 4.9 ± 0.41Kg and 4.7 ± 0.43Kg respectively. Animals of B. bubalis and Bos. taurus species infected experimentally with Babesia bigemina and Theleria annulata showed irregular and prolonged estrous cycle whereas healthy animals showed normal estrous cycle. The duration of estrous cycle observed in Babesiosis affected animals was 76.0±4.4 days, 65.0±3.29 days, 58±5.2days and 47.0 ± 4.2 days. The duration of estrous cycle in Theileriosis affected Bos species was 63.0 ± 8.57, 68.0 ± 10.0 and 31.0 ± 5.7 days respectively.

Low and high postpubertal ethanol use: damage on adulthood reproduction and offspring

Graphical abstract The relationship between adolescent ethanol uses and its impacts throughout life are not conclusive. Thus, we evaluated if the low and high consumption of ethanol at postpuberty interferes with the reproduction and ethanol-naive offspring and if the effects are dose-related. Female and male rats were divided into three groups: low drinker (L), high drinker (H) and control (C). The L and H groups were exposed to ethanol up to 10 % from 65 to 80 days with withdrawal after this period. The ethanol consumed by low drinkers was 1.41 ± 0.21 g/kg/day and by high drinkers 4.59 ± 0.45 g/kg/day. The study was conducted in two phases. The first phase verified the reproductive capacity in adulthood on generations (litter size and sex ratio). Data were collected over 10 years. The second phase analyzed the parent reproductive parameters (body weight, reproductive organ weight, sperm parameters and estrous cycle) and the pup development. We observed a reduced litter size in both drinker groups. Gestational body weight gain and feed consumption were lower in L and H. We observed an alteration in reproductive organs weight in both sexes of H. Females presented a longer estrous cycle duration. Males presented an increase in abnormal sperm, a decrease in sperm count and accelerated transit time. The ethanol-naive offspring development was also impaired. We conclude that low and high postpubertal alcohol use impairs long-term reproductive parameters, even after alcohol withdrawal. There is also impaired ethanol-naive offspring. Besides, the effects are dose-related.Lay summaryThe effects of alcohol use have been reported in several studies. However, better knowledge about early alcohol use and its impact on reproduction in adulthood, after abstinence and on ethanol-naive offspring could help improve preventive measures and mechanisms of action. One of the methods used was retrospective analysis which allows to evaluate the effects of postpubertal ethanol use on the reproductive capacity of rats over generations. Despite our limitations, we verified that the post-adolescent period acts as a susceptibility window, and lifestyle at this age modulates the long-term reproductive parameters. The early ethanol use impairs reproduction function since sperm parameters and the estrous cycle have been altered. The dose of alcohol also contributes to damage on the drinkers’ reproduction and on the physical development of ethanol-naive offspring. Future studies are necessary to identify the mechanism involved in long-term alcohol use effects, even in withdrawal, as well as ethanol-naive offspring outcomes.

Effects of early life adversity on male reproductive behavior and the medial preoptic area transcriptome.

Early life adversity can alter reproductive development in humans, changing the timing of pubertal onset and sexual activity. One common form of early adversity is limited access to resources. This adversity can be modeled in rats using the limited bedding/nesting model (LBN), in which dams and pups are placed in a low resource environment from pups'postnatal days 2-9. Our laboratory previously found that adult male rats raised in LBN conditions have elevated levels of plasma estradiol compared to control males. In females, LBN had no effect on plasma hormone levels, pubertal timing, or estrous cycle duration. Estradiol mediates male reproductive behaviors. Thus, here we compared reproductive behaviors in adult males exposed to LBN vs. control housing. LBN males acquired the suite of reproductive behaviors (mounts, intromissions, and ejaculations) more quickly than their control counterparts over 3 weeks of testing. However, there was no effect of LBN in males on puberty onset or masculinization of certain brain regions, suggesting LBN effects on estradiol and reproductive behaviors manifest after puberty. In male and female rats, we next used RNA sequencing to characterize LBN-induced transcriptional changes in the medial preoptic area (mPOA), which underlies male reproductive behaviors. LBN produced sex-specific alterations in gene expression, with many transcripts showing changes in opposite directions. Numerous transcripts altered by LBN in males are regulated by estradiol, linking hormonal changes to molecular changes in the mPOA. Pathway analysis revealed that LBN induced changes in neurosignaling and immune signaling in males and females, respectively. Collectively, these studies reveal novel neurobiological mechanisms by which early life adversity can alter reproductive strategies.

Analysis of Indirect Biomarkers of Effect after Exposure to Low Doses of Bisphenol A in a Study of Successive Generations of Mice.

Simple SummaryLiving beings are constantly and inadvertently exposed to a series of environmental and food pollutants, triggering effects on health that are transmitted over generations. Bisphenol A is a compound produced in large amounts world-wide and used in the manufacture of plastic containers and other utensils for daily use. It is an environmental and food pollutant with a demonstrated capacity to produce effects on the health of organisms exposed to it. The objective of our study was to identify possible indirect biomarkers of effect by means of the analysis of the blood biochemistry, and of certain reproductive parameters of animals exposed to Bisphenol A in doses considered to be safe over different generations. Our results did not show any modifications in the reproduction parameters evaluated, such as the duration of the estrous cycle, the size of the litters, or the percentage of the young alive at weaning time. However, they showed that there were alterations in biochemical parameters like glucose, total proteins, and albumin, which could therefore, be regarded as indirect indicators of an early effect of alterations in health caused by this compound.Bisphenol A (BPA) is considered as being an emerging pollutant, to which both animal and human populations are continuously and inadvertently exposed. The identification of indirect biomarkers of effect could be a key factor in determining early adverse outcomes from exposure to low doses of BPA. Thus, this study on mice aims to evaluate and identify indirect biomarkers of effect through the analysis of their blood biochemistry, and of certain reproduction parameters after exposure to different BPA concentrations (0.5, 2, 4, 50, and 100 µg/kg BW/day) in drinking water over generations. Our results showed that there were no modifications in the reproductive parameters evaluated, like estrous cycle duration, litter size, or the percentage of the young alive at reaching the weaning stage, at the exposure levels evaluated. However, there were modifications in the biochemical parameters, e.g., alterations in the glucose levels, that increased significantly (p < 0.05) in the breeders at the higher exposure doses (50 and 100 µg/kg BW/day in F1; 50 µg/kg BW/day in F2 and 100 µg/kg BW/day in F3), that would suggest that the BPA could induce hyperglycemia and its complications in adult animals, probably due to some damage in the pancreas cells; albumin, that increased in the breeders exposed to the highest dose in F1 and F3, inferring possible hepatic alterations. Further, total proteins showed a diminution in their values in F1 and F2, except the group exposed to 100 µg/kg BW/day, whereas in F3 the values of this parameter increased with respect to the control group, this aspect likely being related to a possible hepatic and renal alteration. Based on these results, glucose, albumin, and total proteins could initially be considered as early indicators of indirect effect after prolonged exposure to low BPA doses over generations.

Exposure to microplastics leads to a defective ovarian function and change in cytoskeleton protein expression in rat.

Microplastics (MPs) are ubiquitous environmental contaminants; through their physicochemical properties, they can have potentially negative effects on the environment as well as on animal and human health. Studies addressing the toxicity of MPs on mammalian female reproduction are almost absent. Thus, the main objective of the present study was to assess the impact of oral exposure, during four estrous cycles, of 5µm polystyrene-type microplastics (PS-MPs) on ovarian function in rats. Particles of PS-MPs were detected in the duodenum and, for the first time, in the different compartments of the ovarian tissue. The toxicity of accumulated PS-MPs was manifested by the reduced relative ovarian weights, by the alteration in the folliculogenesis and in the estrous cycle duration, and by the reduced serum concentration of estradiol. The defective ovarian function following PS-MP treatment might be due to the induction of oxidative stress, which has been proved by an increased malondialdehyde (MDA) concentration and an increased superoxide dismutase (SOD) and catalase (CAT) activities as well as a decreased protein sulfhydryl (PSH) level in the rat ovary. Importantly, by immunofluorescence and RT-PCR, we demonstrated a significant decrease in the expression of cytoskeletal proteins: α-tubulin and disheveled-associated activator of morphogenesis (DAAM-1) in the ovary of rats exposed to PS-MPs at proteomic and transcriptomic levels. Our results uncovered, for the first time, the distribution and accumulation of PS-MPs across rat ovary, revealed a significant alteration in some biomarkers of the ovarian function, and highlighted the possible involvement of MP-induced disturbance of cytoskeleton in these adverse effects.

Продължителност на еструса и половия цикъл при кобили от породата Хафлингер

A study of the duration of oestrus and estrous cycles in mares from Haflinger breed (HB) and the influence of some factors was conducted. The records used for this study were from the breeding registers of the mares from the State Stud farm Kabiuk near Shumen, covering a period of 11 years (2009 to 2020). In the study were included 15 mares with 110 estruses and 22 estrous cycles. With the mares from Haflinger breed, the average duration of oestrus is 5.52 ± 0.26 days and the length of the estrous cycle is 24.21 ± 1.13 days. The year (P<0.001), month (P<0.001), season (P<0.05), and length of the estrous cycle - the year of fertilization (P<0.05) had reliable influence on the duration of oestrus. In Haflinger mares, the shortest estrus is in the middle and at the end of the breeding season (March: 4.39 ± 0.46 days, July: 3.33 ± 0.82 days). Its duration increases during the winter season and reaches its peak in the middle of spring (February: 5.96 ± 0.51 days, April: 8.37 ± 0.72 days).

Estrous activity in lactating cows with divergent genetic merit for fertility traits

This observational study aimed to determine the effect of genetic merit for fertility traits on estrous expression and estrous cycle duration in grazing dairy cows, as measured by an activity monitoring device. A secondary aim was to describe changes in expression of estrus that occur during successive estrous cycles postpartum. Neck-mounted, activity-monitoring devices (Heatime, SCR Engineers Ltd.) were fitted to nulliparous Holstein-Friesian heifers with positive (POS FertBV) or negative genetic merit for fertility traits (NEG FertBV) to capture activity data during their first and second lactations (POS FertBV: n = 242, n = 188; NEG FertBV: n = 159, n = 87 in lactation 1 and 2, respectively). An estrous event was identified when the activity change index exceeded 26 activity units (AU) for 4 h. A total of 1,254 and 892 estrous events were identified in lactation 1 and 2, respectively. Estrous duration was defined as the interval between when the threshold was first exceeded and when activity dropped below the threshold, with no new event starting within 24 h of the end of the previous event. This definition of estrus included cows in which activity crossed the threshold multiple times in a day and were classified as a single estrous event. A second measure, high activity duration, was defined as the total hours that activity exceeded the threshold. To characterize estrous activity, peak activity (above baseline) and total activity (area under the curve of activity above baseline) were measured. Compared with NEG FertBV cows, POS FertBV cows had more active, longer estrous events. In lactation 1, the POS FertBV group had a mean estrous duration and a high activity duration of 12.5 and 12.4 h compared with 11.4 and 11.3 h for the NEG FertBV group [standard error of the difference (SED) = 0.5 and 0.4 h, respectively]. This significant difference also occurred in lactation 2, with a mean estrous duration of 13.1 versus 11.8 h (SED = 0.5 h) and a high activity duration of 13.0 versus 11.8 h (SED = 0.4 h) in the POS and NEG FertBV groups, respectively. Total activity and peak activity were greater in the POS compared with the NEG FertBV group in lactation 1 (peak activity: 65.5 vs. 55.8 AU, SED = 2.4 AU; total activity: 588 vs. 494 AU, SED = 25 AU) and lactation 2 (peak activity: 72.5 vs. 61.2 AU, SED = 2.9 AU; total activity: 648 vs. 541 AU, SED = 30 AU). Estrous cycle duration did not differ between the POS and NEG FertBV groups (lactation 1: 20.4 vs. 20.6 d, SED = 0.25; lactation 2: 20.8 vs. 21.0 d, SED = 0.28). Less estrous activity of the cow was associated with the first postpartum estrus. In contrast, the number of previous estrous events did not consistently affect the duration of the subsequent estrous cycle. The outcomes of this study provide evidence that positive genetic merit for fertility traits is associated with more overt estrous expression. Selection for these traits may improve estrous expression and thus estrous detection in commercial herds.

Exposure of Adult Female Mice to Low Doses of di(2-ethylhexyl) Phthalate Alone or in an Environmental Phthalate Mixture: Evaluation of Reproductive Behavior and Underlying Neural Mechanisms.

Background:We have previously shown that adult male mice exposure to low doses of an ubiquitous endocrine disruptor, di(2-ethylhexyl) phthalate (DEHP), alters courtship behavior.Objective:The effects of adult exposure to low doses of DEHP alone or in an environmental phthalate mixture on estrous cyclicity, reproductive behavior, and underlying neural structures were analyzed in female mice.Methods:Two-month-old C57BL/6J females were exposed orally for 6 wk to DEHP alone (0, 5 or ) or to DEHP () in a phthalate mixture. Estrous cyclicity was analyzed in intact mice, and behavior [lordosis, olfactory preference, partner preference, ability to stimulate male ultrasonic vocalizations (USVs)] was measured in ovariectomized mice primed with estradiol and progesterone. Immunohistochemical studies were conducted in the neural structures involved in behavior for estrogen receptor (ER) and progesterone receptor (PR).Results:Exposure to DEHP alone or in mixture lengthened the estrous cycle duration, with a shorter proestrus and longer estrus and metestrus stages. Under normalized hormonal levels, females exposed to DEHP alone or in mixture exhibited altered olfactory preference. A lower lordosis behavior and ability to attract and stimulate male emission of courtship USVs was observed, probably due to modifications of pheromonal emission in exposed females. The behavioral alterations were associated with a lower number of PR-expressing neurons, without changes in , in the neural circuitry underlying sexual behavior. The majority of effects observed was comparable between the two DEHP doses and were driven by DEHP in the mixture.Conclusions:Exposure to environmental doses of DEHP alone or in mixture altered several components of female sexual behavior in mice, probably through selective disruption of neural PR signaling. Together with the previously reported vulnerability of male mice, this finding suggests a major impact of exposure to phthalates on sexual reproduction, including in other species with similar neural regulatory processes. https://doi.org/10.1289/EHP7662

Parents ethanol use impairs ethanol-naive offspring development and reproduction.

Parental ethanol consumption can influence the offspring phenotype. In this way, we analyzed the impairments of maternal and paternal high ethanol consumption during postpuberty on the physical development, feeding pattern, puberty onset and reproductive function of ethanol-naive offspring to birth to adulthood. Female and male UChB rats (voluntary 10%, v/v ethanol consumer) were divided into a control group (C) and an ethanol exposed group (E) from 65 to 80 days of age. The C and E were mated at 100 days. The maternal parameters and offspring development and reproduction parameters were monitored. We observed reduced feeding intake and body weight in the dams of E group throughout gestation and lactation period. Delay in physical development, lower body weight and altered feeding pattern were observed in female and male offspring of E group. In addition, the puberty onset was delayed in both sexes, with lower testosterone levels in the juvenile and pubertal males. There was a prolongation on the estrous and proestrus phases in females from E but the estrous cycle duration did not change between groups. Ovary and uterus weight were reduced in pubertal and adult females from E group. Reduced epididymis and seminal vesicle weight, increased sperm abnormalities, decrease in the daily sperm production and accelerated epididymal transit time were observed in E males. The high maternal and paternal ethanol use on postpuberty impairs the parameters of ethanol-naive offspring inducing alteration on development and reproduction.

The effects of the estrous cycle, menopause, and recording condition on female rat ultrasonic vocalizations

The goal of this study was to evaluate the effects of ovarian hormones on female rat ultrasonic vocalizations (USVs). Twenty (10 control and 10 ovariectomized) 3-month-old female rats were recorded in 3 recording conditions (elicitation, dyad, and isolation) over a full estrous cycle or time-matched duration. There were differences in USV acoustics (frequency and complexity parameters) across recording conditions but no differences in USV acoustics between control and ovariectomized groups. USVs produced in isolation had lower frequency and complexity parameters than elicited USVs for both control and ovariectomized rats. Additionally, for control rats, USV parameters of frequency, complexity, duration, and intensity changed depending on the estrous state. Therefore, although fluctuating hormone levels may influence USV acoustics, this variation can be controlled for by ovariectomizing female rats.

First evidence of the protective role of melatonin in counteracting cadmium toxicity in the rat ovary via the mTOR pathway.

Herein, the first evidence of the ability of melatonin (MLT) to counteract cadmium (Cd) toxic effects on the rat ovary is reported. Cd treatment, enhancing oxidative stress, provoked clear morphological, histological and biomolecular alterations, i.e. in the estrous cycle duration, in the ovarian and serum E2 concentration other than in the steroidogenic and folliculogenic genes expression. Results demonstrated that the use of MLT, in combination with Cd, avoided the changes, strongly suggesting that it is an efficient antioxidant for preventing oxidative stress in the rat ovary. Moreover, to explore the underlying mechanism involved, at molecular level, in the effects of Cd-MLT interaction, the study focused on the mTOR and ERK1/2 pathways. Interestingly, data showed that Cd influenced the phosphorylation status of mTOR, of its downstream effectors and of ERK1/2, inducing autophagy and apoptosis, while cotreatment with MLT nullified these changes. This work highlights the beneficial role exerted by MLT in preventing Cd-induced toxicity in the rat ovary, encouraging further studies to confirm its action on human ovarian health with the aim to use this indolamine to ameliorate oocyte quality in women with fertility disorders.

Factors affecting oocyte recovery and pregnancy rates of fresh and frozen/thawed ICSI embryos

The aim of the present study was to verify how repeated ovum pick-up (OPU), performed in anestrous and cyclic mares, affect ovarian activity, measured by progesterone (P4) and 17ß-estradiol (E2) plasma levels. Ovum pick-up of all visible follicles was performed every 9 to 12 days, and four sessions were carried out during anestrous (A) and breeding season (BS). The number of aspirated follicles per mare at each session was not significantly different between the two periods (BS: 6.1 ± 2.4; A: 7.5 ± 4.4; P > 0.05), but the mean follicular diameter was significantly higher during BS (16.0 ± 7.1 vs. 10.2 ± 5.1 mm; P < 0.05); during A the number of aspirated follicles less than 15 mm in diameter resulted significantly higher than that registered in BS (5.1 ± 2.7 vs. 3.0 ± 1.8; P < 0.05). The total mean value of P4 was higher in BS than in A (6.3 ± 4.4 vs. 0.3 ± 1.8 ng/mL; P < 0.05), whereas the total mean level of E2 was not different between the two periods (3.8 ± 3.4 vs. 2.5 ± 2.7 pg/mL; P > 0.05). Estradiol plasma values resulted positively correlated, in A and BS, with diameter of follicles detected on the ovaries (R = 0.345 and R = 0.331, respectively), whereas a negative correlation was observed between P4 and follicular diameter in BS (R = −0.162). Both E2 and P4 presented a high individual variability during BS; in particular, in three of seven mares, P4 trend was compatible with a normal estrous cycle, and the interval between two consecutive peaks was 21 days. In two of seven mares, with CL at first OPU, P4 concentrations remained more than 3 ng/mL throughout the entire treatment period. Finally, in two of seven animals, P4 levels initially showed a similar pattern to that of a normal estrous cycle, then, after the second aspiration, they remained consistently higher than 3 ng/mL. When the procedure was carried out in cyclic animals, the influence of this technique on ovarian activity seemed to be related to individual variability although, according to progesterone values, structures observed on the ovaries after aspirations presented luteal function. Furthermore, the resumption of normal ovarian activity, after repeated OPU sessions, occurred in a period not much longer than the duration of a normal estrous cycle (25.4 ± 5.2 days). Data recorded during nonbreeding period showed that repeated OPU in anestrous mares do not affect ovarian activity and do not anticipate the resumption of ovarian cyclicity. However, based on the number of aspirated follicles in anestrous and cyclic mares, both types of subjects could be considered as oocyte donors.

Effect of neuronal nitric oxide synthase serine-1412 phosphorylation on hypothalamic-pituitary-ovarian function and leptin response.

Hypothalamic neuronal nitric oxide synthase (nNOS) potentiates adult female fertility in rodents by stimulating gonadotropin releasing hormone (GnRH) secretion, which in turn promotes luteinizing hormone (LH) release and ovulation. The mechanism of hypothalamic nNOS activation is not clear but could be via nNOS serine1412 (S1412) phosphorylation, which increases nNOS activity and physiologic NO effects in other organ systems. In female rodents, hypothalamic nNOS S1412 phosphorylation reportedly increases during proestrus or upon acute leptin exposure during diestrus. To determine if nNOS S1412 regulates female reproduction in mice, we compared the reproductive anatomy, estrous cycle duration and phase proportion, and fecundity of wild-type and nNOS serine1412➔alanine (nNOSS1412A) knock-in female mice. We also measured hypothalamic GnRH and serum LH, follicle stimulating hormone (FSH), estradiol, and progesterone in diestrus mice after intraperitoneal leptin injection. Organ weights and histology were not different by genotype. Ovarian primordial follicles, antral follicles, and corpora lutea were similar for wild-type and nNOSS1412A mice. Likewise, estrous cycle duration and phase length were not different, and fecundity was unremarkable. There were no differences among genotypes for LH, FSH, estradiol, or progesterone. In contrast to prior studies, our work suggests that nNOS S1412 phosphorylation is dispensable for normal hypothalamic-pituitary-ovarian function and regular estrous cycling. These findings have important implications for current models of fertility regulation by nNOS phosphorylation.

Influence of estrous stages on electrocardiography, clinical pathology and ovarian weight of experimental beagle dogs: a retrospective analysis.

Estrous cycle is a repetitive phenomenon occurring during the reproductive life of a female dog. The duration of the canine estrous cycle is considerably longer than one in the most of the other animals and is broadly grouped into follicular phase (proestrus and estrus), luteal phase (diestrus) and non-seasonal anestrus. Dogs in the same stage of cycle can be inadvertently assigned to same group during routine safety and metabolic studies leading to possible erroneous interpretation of test-item related effects. This retrospective analysis was conducted by analyzing data of 86 female beagle dogs from control/placebo treated groups to correlate any possible effect of estrous stages with electrocardiography, clinical pathology and ovarian weight. Different estrous cycle stages of beagles were confirmed histologically by evaluating ovary, uterus, vagina and mammary glands. The incidence of beagles in diestrus was the highest, followed by anestrus, proestrus and estrus. No significant effect was noticed on heart rate, P–A, P–D, RR, QRS and QT intervals across different stages of estrous cycle. However, significantly higher PQ (PR) interval in dogs in proestrus stage was observed compared to dogs in anestrus and estrus. Marginally higher WBCs, neutrophils, lymphocytes, RBCs, hemoglobin, AST and lower hematocrit, lipid profile (total cholesterol, HDL, LDL, triglycerides), ALP level was evident in estrous period. Relative ovary weight was significantly higher in dogs in diestrus stage. Considering these results, one may need to exercise caution while interpreting experimental data from female beagle dogs.

Association between duration of obesity and severity of ovarian dysfunction in rat-cafeteria diet approach

Consumption of unhealthy, energy-dense palatable food during early age leads to obesity in children and the onset of obesity during childhood has a profound effect on the reproductive health of women. In this study, the mechanism underlying diet-induced obesity on ovarian dysfunction was studied by exposing rats to cafeteria diet (CAFD) for two different durations. For that purpose, 21-day-old female Sprague Dawley rats were fed ad libitum with a standard diet (control group) and a cafeteria diet (CAFD group) for a period of 20 weeks (20 W) and 32 weeks (32 W). We observed obesity, hyperglycemia, hyperlipidemia, hyperleptinemia and hypoadiponectinemia in CAFD fed groups. Hyperinsulinemia, hypergonadotrophism, hypertestosteronemia and hyperprogesteronemia were observed in the 20 W-CAFD group. Conversely, in the 32 W-CAFD group hypersecretion declined to hyposecretion. The levels of estradiol remained low during both time periods. The duration of estrous cycle was extended in the CAFD fed rats. The ovary weight was higher in the 20 W-CAFD fed rats but it was drastically reduced over a longer duration cafeteria diet feeding. In the 20 W-CAFD fed rats, the protein levels of LHR, StAR, CYP11A1, 3β-HSD and 17β-HSD were increased but FSHR and CYP19A1 levels were decreased in the ovary. On the other hand, gonadotropin receptor and the protein levels of steroidogenic enzymes were decreased in the ovary of 32 W-CAFD fed rats. We conclude that the duration of energy-dense diet consumption has differential regulatory mechanism in altering the ovarian steroid production. In 20 W-CAFD fed rats, hypergonadotropic condition was observed whereas, 32 W-CAFD consumption induced hypogonadotropic hypogonadism.

Early Life Stress Delays Sexual Maturation in Female Mice.

In humans, some forms of early life stress (ELS) have been linked with precocious puberty, altered brain maturation, and increased risk for a variety of forms of pathology. Interestingly, not all forms of ELS have been found to equally impact these metrics of maturation. In recent work, we have found that ELS in the form of limited bedding (LB) from P4 to P11, was associated with precocious hippocampus maturation in males and increased risk for depressive-like pathology and attentional disturbance in female mice. Here, we sought to test whether ELS in the form of LB also impacted the timing of sexual maturation in female mice. To establish rate of somatic and sexual development, distinct cohorts of mice were tested for weight gain, timing of vaginal opening, and development of estrous cycling. ELS animals weighed significantly less than controls at every timepoint measured. Onset of vaginal opening was tracked from P21 to 40, and ELS was found to significantly delay the onset of vaginal opening. To test the impact of ELS on estrous cycle duration and regularity, vaginal cytology was assessed in independent groups of animals using either a continuous sampling (daily from P40 to P57) or random sampling approach (single swab at P35, P50, or P75). ELS did impact measures of estrous cycling, but these effects were dependent upon the sampling method used. We also tested the impact of ELS on anxiety-like behaviors over development and across the estrous cycle. We observed a developmental increase in anxiety-like behavior in control but not ELS mice. No effect of estrous cycle stage was found on anxiety-like behavior for either group of mice. Together these results provide evidence that ELS in the form of LB delays somatic and sexual development. Additional work will be required to determine the mechanism by which ELS impacts these measures, and if these effects are common to other models of ELS in rodents.

Evaluation of the toxicity and anti-inflammatory activities of the infusion of leaves of Campomanesia guazumifolia (Cambess.) O. Berg

Ethnopharmacological relevanceSome species of Campomanesia are used in the folk medicine due to anti-inflammatory, anti-diarrheal, anti-diabetes and hypercholesterolemic. However studies with Campomanesia guazumifolia (Cambess.) O. Berg. are scarce. Aim of the studyThis study investigated the anti-inflammatory activity and toxicological profile of infusion obtained from leaves of Campomanesia guazumifolia in mice. Materials and methodsLeaves infusion of C. guazumifolia was obtained in the proportion of 20 g/L (leaves/water) at 95–100 °C for 10 min in an enclosed container. The acute toxicity of the leaves infusion of C. guazumifolia lyophilized (ICG) was assessed by oral administration to female mice at doses of 500, 1000, 2000, and 5000 mg/kg, and the general behavior and toxic symptoms were observed for 14 days. In the subacute toxicity model, female mice were treated orally with the ICG (250, 500, and 1000 mg/kg) during 28 days, and biochemical, toxic signs and the estrous cycle were evaluated. The anti-inflammatory activity of the ICG (70, 300 and 700 mg/kg) was analyzed using carrageenan-induced pleurisy and inflammatory paw (mechanical and thermal hyperalgesia). ResultsThree flavonoids glycosylated and a cyclohexanecarboxylic acid were identified in the ICG: quercetin pentose, quercetin deoxyhexoside, myricetin deoxyhexoside and quinic acid. No clinical signs of acute toxicity were observed, suggesting that the LD50 (Lethal Dose) is above 5000 mg/kg. Subacute exposure of mice to the ICG did not change significantly the hematological and biochemical parameters as well as histology of organs. The ICG increased the duration of estrous cycle in all phases, showing anti-inflammatory potential by decreasing leukocyte migration, extravasation protein in the pleural cavity and antiedematogenic activity. The ICG treatment at a dose of 700 mg/kg decreased the mechanical hyperalgesia, while at doses of 300 mg/kg and 700 mg/kg, decreased the sensitivity to the cold. ConclusionThe results evidenced the anti-inflammatory potential with low toxicity of infusion of the leaves of C. guazumifolia, supporting the popular use of this species.