-
Frontiers in Veterinary Science 2022Sheep exhibit a distinct estrous cycle that includes four different phases: proestrus, estrus, late estrus, and luteal phase. As the estrous cycle repeats, follicular...
Sheep exhibit a distinct estrous cycle that includes four different phases: proestrus, estrus, late estrus, and luteal phase. As the estrous cycle repeats, follicular development regularly alternates. We thus investigated ovarian transcriptome data from each of the four phases using weighted gene co-expression network analysis (WGCNA) to identify modules, pathways, and genes essential to follicle growth and development. We clustered mRNA and long non-coding RNA (lncRNA) into different modules by WGCNA, and calculated correlation coefficients between genes and Stages of the estrous cycle. Co-expression of the black module (cor = 0.81, <0.001) and the yellow module (cor = 0.61, <0.04) was found to be critical for follicle growth and development. A total of 2066 genes comprising the black and yellow modules was used for functional enrichment. The results reveal that these genes are mainly enriched in Cell cycle, PI3K-Akt signaling pathway, Oocyte meiosis, Apoptosis, and other important signaling pathways. We also identified seven hub genes (, and ) that may play a role in follicle development. Our study may provide several important new markers allowing in depth exploration of the genetic basis for multiparous reproduction in sheep.
PubMed: 36601328
DOI: 10.3389/fvets.2022.1057282 -
The Journal of Veterinary Medical... Jul 2015We measured the plasma levels of amino acids at various reproductive stages in female rats, including the estrous cycle, pregnancy and lactation, and compared the...
We measured the plasma levels of amino acids at various reproductive stages in female rats, including the estrous cycle, pregnancy and lactation, and compared the resulting amino acid profiles using two- or three-dimensional figures. These figures revealed that the amino acid profiles of pregnant and lactating dams differed considerably from those during the estrous cycle or in male rats. The plasma levels of individual amino acids were almost the same between proestrus, estrus, metestrus and diestrus, and their profiles did not differ significantly. However, the amino acid profiles changed during pregnancy and lactation in dams. The plasma Ser level decreased significantly in mid and late pregnancy, whereas Tyr, Gly and His decreased significantly in the late and end stages of pregnancy, and Trp and Lys significantly decreased and increased at the end of pregnancy, respectively. Much larger changes in amino acid profiles were observed during lactation, when the levels of many amino acids increased significantly, and none showed a significant decrease. Plasma Pro, Ser and Gly levels increased continuously from day 1 until day 15 of lactation, whereas Asn and Met increased significantly from days 1 and 5 respectively until the end of lactation. These results suggest that the profiles of plasma amino acids show characteristic changes according to reproductive stage and that it may be necessary to consider such differences when performing amino acid-based diagnosis.
Topics: Amino Acids; Animals; Estrous Cycle; Estrus; Female; Lactation; Male; Metestrus; Pregnancy; Pregnancy, Animal; Proestrus; Rats; Rats, Wistar
PubMed: 25787929
DOI: 10.1292/jvms.15-0095 -
Alcoholism, Clinical and Experimental... Sep 2017Ethanol (EtOH)-evoked oxidative stress, which contributes to myocardial dysfunction in proestrus rats, is mediated by increases in NADPH oxidase (Nox) activity,...
BACKGROUND
Ethanol (EtOH)-evoked oxidative stress, which contributes to myocardial dysfunction in proestrus rats, is mediated by increases in NADPH oxidase (Nox) activity, malondialdehyde (MDA), and ERK1/2 phosphorylation. Whether these biochemical responses, which are triggered by alcohol-derived acetaldehyde in noncardiac tissues, occur in proestrus rats' hearts remains unknown. Therefore, we elucidated the roles of alcohol dehydrogenase (ADH), cytochrome P4502E1 (CYP2E1), and catalase, which catalyze alcohol oxidation to acetaldehyde, in these alcohol-evoked biochemical and hemodynamic responses in proestrus rats.
METHODS
Conscious proestrus rats prepared for measurements of left ventricular (LV) function and blood pressure (BP) received EtOH (1.5 g/kg, intravenous [i.v.] infusion over 30 minutes) or saline 30 minutes after an ADH and CYP2E1 inhibitor, 4-methylpyrazole (4-MP) (82 mg/kg, intraperitoneal), a catalase inhibitor, 3-AT (0.5 g/kg, i.v.), their combination, or vehicle. LV function and BP were monitored for additional 60 minutes after EtOH or saline infusion before collecting the hearts for ex vivo measurements of LV reactive oxygen species (ROS), Nox activity, MDA, and ERK1/2 phosphorylation.
RESULTS
EtOH reduced LV function (dP/dt and LV developed pressure) and BP, and increased cardiac Nox activity, ROS and MDA levels, and ERK1/2 phosphorylation. Either inhibitor partially, and their combination significantly, attenuated these responses despite the substantially higher blood EtOH level, and the increased cardiac oxidative stress and reduced BP caused by 3-AT alone or with 4-MP. The inhibitors reduced cardiac MDA level and reversed EtOH effect on cardiac and plasma MDA.
CONCLUSIONS
EtOH oxidative metabolism plays a pivotal role in the EtOH-evoked LV oxidative stress and dysfunction in proestrus rats. Notably, catalase inhibition (3-AT) caused cardiac oxidative stress and hypotension.
Topics: Amitrole; Animals; Blood Pressure; Cardiomyopathies; Catalase; Central Nervous System Depressants; Enzyme Inhibitors; Ethanol; Female; Fomepizole; Neurophysins; Oxidative Stress; Proestrus; Protein Precursors; Pyrazoles; Rats; Rats, Sprague-Dawley; Vasopressins; Ventricular Function, Left
PubMed: 28667748
DOI: 10.1111/acer.13442 -
American Journal of Physiology. Heart... Dec 2022With the increasing appreciation for sex as a biological variable and the inclusion of female mice in research, it is important to understand the influence of the...
With the increasing appreciation for sex as a biological variable and the inclusion of female mice in research, it is important to understand the influence of the estrous cycle on physiological function. Sex hormones are known to modulate vascular function, but the effects of the mouse estrous cycle phase on arterial stiffness, endothelial function, and arterial estrogen receptor expression remain unknown. In 23 female C57BL/6 mice (6 mo of age), we determined the estrous cycle stage via vaginal cytology and plasma hormone concentrations. Aortic stiffness, assessed by pulse wave velocity, was lower during the estrus phase compared with diestrus. In ex vivo assessment of isolated pressurized mesenteric and posterior cerebral arteries, the responses to acetylcholine, insulin, and sodium nitroprusside, as well as nitric oxide-mediated dilation, were not different between estrous cycle phases. In the aorta, expression of phosphorylated estrogen receptor-α was higher for mice in estrus compared with mice in proestrus. In the cerebral arteries, gene expression for estrogen receptor-β () was lowest for mice in estrus compared with diestrus and proestrus. These results demonstrate that the estrus phase is associated with lower in vivo large artery stiffness in mice. In contrast, ex vivo resistance artery endothelial function is not different between estrous cycle phases. Estrogen receptor expression is modulated by the estrus cycle in an artery-dependent manner. These results suggest that the estrous cycle phase should be considered when measuring in vivo arterial stiffness in young female mice. To design rigorous vascular research studies using young female rodents, the influence of the estrous cycle on vascular function must be known. We found that in vivo aortic stiffness was lower during estrus compared with the diestrus phase in female mice. In contrast, ex vivo mesenteric and cerebral artery endothelial function did not differ between estrous cycle stages. These results suggest that the estrous cycle stage should be accounted for when measuring in vivo arterial stiffness.
Topics: Mice; Female; Animals; Vascular Stiffness; Receptors, Estrogen; Pulse Wave Analysis; Mice, Inbred C57BL; Estrous Cycle; Estrogens; Arteries
PubMed: 36240435
DOI: 10.1152/ajpheart.00369.2022 -
Anesthesia Progress Jul 1990Our laboratory has reported changes in luteinizing hormone releasing hormone (LHRH) from the hypothalamus following nitrous oxide (N2O) exposure. LHRH augments LH...
Our laboratory has reported changes in luteinizing hormone releasing hormone (LHRH) from the hypothalamus following nitrous oxide (N2O) exposure. LHRH augments LH release, which in turn causes ovulation. This study evaluated how N2O disrupts ovulation and the possible resulting infertility. Adult virgin female rats (N = 64) were housed with a 12 h:12 h light cycle. Daily vaginal smears were taken and only rats exhibiting two consecutive normal 4-day ovulatory cycles were used. Thirty-two rats were placed in an environmental chamber and exposed to a mix of hydrated 30% N2O and compressed air delivered at 1.6 L/min for 8 h/day for 4 days (one cycle); controls received compressed air. All rats exposed to N2O exhibited disrupted cycles following the first day of the 4-day exposure. From a group of 12 N2O-exposed rats, 11 went into constant proestrus (day of ovulatory surge) for up to 3 weeks. Control rats cycled normally. Following each exposure, eight rats were perfused, brains sectioned, and LHRH cells identified by immunocytochemistry. Eight control rats also underwent this procedure. A threefold increase in LHRH cells was noted in N2O rats. In addition, 12 rats received 30% N2O for 4 days, followed by mating with proven male breeders for 4 days, as were controls. Six of 12 N2O rats and 12 of 12 control rats gave birth. Contrary to previous reports, no significant difference was noted in litter size or weight. The constant proestrus seen after N2O exposure is due to disruption of LHRH cells in the hypothalamus (blocked LHRH release). It is this disruption of LHRH, and therefore ovulation, which results in infertility.
Topics: Animals; Female; Gonadotropin-Releasing Hormone; Hypothalamus; Infertility, Female; Litter Size; Nitrous Oxide; Ovulation; Pregnancy; Proestrus; Rats; Rats, Inbred Strains
PubMed: 2096739
DOI: No ID Found -
Biology of Reproduction Jul 2013Changes in the CD-1 mouse uterine transcriptome during proestrus and estrus were investigated to help elucidate mechanisms of uterine tissue remodeling during the estrus...
Changes in the CD-1 mouse uterine transcriptome during proestrus and estrus were investigated to help elucidate mechanisms of uterine tissue remodeling during the estrus cycle and their regulation by estrogen and progesterone in preparation of the uterus for pregnancy. Mice were staged beginning at 6 weeks of age, and uterine horns were harvested after monitoring two estrus cycles. Microarray analysis of whole uterine horn RNA identified 2428 genes differentially expressed in estrus compared to proestrus, indicating there is extensive remodeling of mouse uterus during the estrus cycle, affecting ~10% of all protein-encoding genes. Many (~50%) of these genes showed the same differential expression in independent analyses of isolated uterine lumenal epithelial cells. Changes in gene expression associated with structural alterations of the uterus included remodeling of the extracellular matrix, changes in cell keratins and adhesion molecules, activation of mitosis and changes in major histocompatibility complex class II (MHCII) presentation, complement and coagulation cascades, and cytochrome P450 expression. Signaling pathways regulated during the estrus cycle, involving ligand-gated channels, Wnt and hedgehog signaling, and transcription factors with poorly understood roles in reproductive tissues, included several genes and gene networks that have been implicated in pathological states. Many of the molecular pathways and biological functions represented by the genes differentially expressed from proestrus to estrus are also altered during the human menstrual cycle, although not necessarily at the corresponding phases of the cycle. These findings establish a baseline for further studies in the mouse model to dissect mechanisms involved in uterine tissue response to endocrine disruptors and the development of reproductive tract diseases.
Topics: Animals; Estrus; Female; Gene Expression Profiling; Mice; Models, Animal; Oligonucleotide Array Sequence Analysis; Polymerase Chain Reaction; Proestrus; Transcriptome; Uterus
PubMed: 23740946
DOI: 10.1095/biolreprod.112.107334 -
ENeuro 2021Kisspeptin-expressing neurons in the anteroventral-periventricular nucleus (AVPV) are part of a neural circuit generating the gonadotropin-releasing hormone (GnRH)...
Kisspeptin-expressing neurons in the anteroventral-periventricular nucleus (AVPV) are part of a neural circuit generating the gonadotropin-releasing hormone (GnRH) surge. This process is estradiol-dependent and occurs on the afternoon of proestrus in female mice. On proestrus, AVPV kisspeptin neurons express more kisspeptin and exhibit higher frequency action potentials and burst firing compared with diestrus, which is characterized by a pulsatile rather than a prolonged surge of GnRH secretion. We hypothesized changes in voltage-gated potassium conductances shape activity profiles of these cells in a cycle-dependent manner. Whole-cell voltage-clamp recordings of GFP-identified AVPV kisspeptin neurons in brain slices from diestrous and proestrous mice revealed three subcomponents of the voltage-sensitive K current: fast-transient slow-transient, and residual. During proestrus, the V of inactivation of the fast-transient current was depolarized and the amplitude of the slow-transient component was reduced compared with diestrus; the residual component was consistent across both stages. Computational models were fit to experimental data, including published estrous-cycle effects on other voltage-gated currents. Computer simulations suggest proestrus-typical K currents are suppressive compared with diestrus. Interestingly, larger T-type, persistent-sodium, and hyperpolarization-activated currents during proestrus compensate for this suppressive effect while also enabling postinhibitory rebound bursting. These findings suggest modulation of voltage-gated K and multiple subthreshold depolarizing currents across the negative to positive feedback transition maintain AVPV kisspeptin neuron excitability in response to depolarizing stimuli. These changes also enable firing in response to hyperpolarization, providing a net increase in neuronal excitability, which may contribute to activation of this population leading up to the preovulatory GnRH surge.
Topics: Animals; Estradiol; Estrous Cycle; Female; Gonadotropin-Releasing Hormone; Hypothalamus, Anterior; Kisspeptins; Mice; Neurons; Potassium
PubMed: 34385153
DOI: 10.1523/ENEURO.0324-21.2021 -
Molecular Medicine (Cambridge, Mass.) 2006Hypoxia produces sex dimorphic immune responses in males and proestrus females. Because Kupffer cells are the major source of proinflammatory cytokines, studies were... (Comparative Study)
Comparative Study
Hypoxia produces sex dimorphic immune responses in males and proestrus females. Because Kupffer cells are the major source of proinflammatory cytokines, studies were conducted to discern IL-6 production in mouse Kupffer cells following hypoxia. Hypoxia enhances TLR4 expression in Kupffer cells irrespective of sex. However, MyD88 and Src expression in Kupffer cells decreased significantly after hypoxia in proestrus females, whereas Src protein expression and phosphorylation increased in males in concurrence with differences in IL-6 production. 17beta-estradiol administration elevated MyD88 and Src expression in males to levels in normoxic proestrus females. Administration of Src inhibitor in hypoxic males prevented increased IL-6 production. Thus, differential regulation of MyD88 and Src in males and females plays an important role in sex-specific immune response following hypoxia.
Topics: Animals; Cell Culture Techniques; Cells, Cultured; Estradiol; Female; Hypoxia; Interleukin-6; Kupffer Cells; Male; Mice; Mice, Inbred C3H; Myeloid Differentiation Factor 88; Phosphorylation; Proestrus; Pyrazoles; Pyrimidines; Sex Characteristics; Toll-Like Receptor 4; src-Family Kinases
PubMed: 16953563
DOI: 10.2119/2006-00030.Zheng -
International Neurourology Journal Sep 2018To characterize the relationship between serum estradiol levels and the expression of glucose transporter type 4 (Glut4) in the pubococcygeus and iliococcygeus muscles...
PURPOSE
To characterize the relationship between serum estradiol levels and the expression of glucose transporter type 4 (Glut4) in the pubococcygeus and iliococcygeus muscles in female rats.
METHODS
The muscles were excised from virgin rats during the metestrus and proestrus stages of the estrous cycle, and from sham and ovariectomized rats implanted with empty or estradiol benzoate-filled capsules. The expression of estrogen receptors (ERs) was inspected in the muscles at metestrus and proestrus. Relative Glut4 expression, glycogen content, and serum glucose levels were measured. Appropriate statistical tests were done to identify significant differences (P≤0.05).
RESULTS
The pubococcygeus and iliococcygeus muscles expressed ERα and ERβ. Glut4 expression and glycogen content in the pubococcygeus muscle were higher at proestrus than at metestrus. No significant changes were observed in the iliococcygeus muscle. In ovariectomized rats, the administration of estradiol benzoate increased Glut4 expression and glycogen content in the pubococcygeus muscle alone.
CONCLUSION
High serum estradiol levels increased Glut4 expression and glycogen content in the pubococcygeus muscle, but not in the iliococcygeus muscle.
PubMed: 30286578
DOI: 10.5213/inj.1836116.058 -
Reproduction in Domestic Animals =... Mar 2021Follistatin-like 3 (FSTL3) is a regulator of cellular apoptosis and was previously identified via RNA-Seq to be associated with follicular development in mammalian...
Follistatin-like 3 (FSTL3) is a regulator of cellular apoptosis and was previously identified via RNA-Seq to be associated with follicular development in mammalian ovaries. However, the mechanism underlying the FSTL3 regulation of oestrus in sheep remained poorly understood. In this study, the oestrogen (E2) and progesterone (P4) concentrations in blood were detected, and the expression level and functional analysis of FSTL3 in the ovary were studied during the different reproductive stage in Aohan fine wool sheep (seasonal breeding breed in China). The concentrations of E2 and P4 at the anestrus were significantly lower compared to dioestrus, proestrus and oestrus stages. Higher expression levels of FSTL3 were observed in the sheep ovary, hypothalamus, and thyroid. During different reproductive stages, higher expression levels were found during the stages of dioestrus and proestrus, while lower levels were found during the oestrus and anestrus stages. Functional analysis of FSTL3 was performed in primary granulosa cells (GCs) of sheep. The concentration of E2 increased significantly after RNAi interference of FSTL3, while the P4 level decreased. FSTL3 can decrease P4 levels, which might be involved in mediating oestrous cycle in sheep.
Topics: Animals; Estrogens; Estrous Cycle; Female; Follistatin-Related Proteins; Gene Expression; Ovary; Progesterone; Sheep
PubMed: 33314336
DOI: 10.1111/rda.13879