P38α MAPK is a gatekeeper of uterine progesterone responsiveness at peri-implantation via Ube3c-mediated PGR degradation.

Estrogen and progesterone specify the establishment of uterine receptivity mainly through their respective nuclear receptors, ER and PR. PR is transcriptionally induced by estrogen-ER signaling in the endometrium, but how the protein homeostasis of PR in the endometrium is regulated remains elusive. Here, we demonstrated that the uterine-selective depletion of P38α derails normal uterine receptivity ascribed to the dramatic down-regulation of PR protein and disordered progesterone responsiveness in the uterine stromal compartment, leading to defective implantation and female infertility. Specifically, Ube3c, an HECT family E3 ubiquitin ligase, targets PR for polyubiquitination and thus proteasome degradation in the absence of P38α. Moreover, we discovered that P38α restrains the polyubiquitination activity of Ube3c toward PR by phosphorylating the Ube3c at serine741 . In summary, we provided genetic evidence for the regulation of PR protein stability in the endometrium by P38α and identified Ube3c, whose activity was modulated by P38α-mediated phosphorylation, as an E3 ubiquitin ligase for PR in the uterus.

ACE2: a key modulator of the renin-angiotensin system and pregnancy.

Angiotensin-converting enzyme 2 (ACE2) is a membrane-bound protein containing 805 amino acids. ACE2 shows approximately 42% sequence similarity to somatic ACE but has different biochemical activities. The key role of ACE2 is to catalyze the vasoconstrictor peptide angiotensin (ANG) II to Ang-(1-7), thus regulating the two major counterbalancing pathways of the renin-angiotensin system (RAS). In this way, ACE2 plays a protective role in end-organ damage by protecting tissues from the proinflammatory actions of ANG II. The circulating RAS is activated in normal pregnancy and is essential for maintaining fluid and electrolyte homeostasis and blood pressure. Renin-angiotensin systems are also found in the conceptus. In this review, we summarize the current knowledge on the regulation and function of circulating and uteroplacental ACE2 in uncomplicated and complicated pregnancies, including those affected by preeclampsia and fetal growth restriction. Since ACE2 is the receptor for SARS-CoV-2, and COVID-19 in pregnancy is associated with more severe disease and increased risk of abnormal pregnancy outcomes, we also discuss the role of ACE2 in mediating some of these adverse consequences. We propose that dysregulation of ACE2 plays a critical role in the development of preeclampsia, fetal growth restriction, and COVID-19-associated pregnancy pathologies and suggest that human recombinant soluble ACE2 could be a novel therapeutic to treat and/or prevent these pregnancy complications.

TNFα blockade reverses vascular and uteroplacental matrix metalloproteinases imbalance and collagen accumulation in hypertensive pregnant rats.

Preeclampsia is a pregnancy-related disorder of maternal hypertension-in-pregnancy (HTN-Preg) and often fetal growth restriction (FGR). Placental ischemia could be an initiating event leading to inadequate vascular and uteroplacental remodeling and HTN-Preg; however, the molecular targets are unclear. To test the hypothesis that placental ischemia-induced release of proinflammatory cytokines target vascular and uteroplacental matrix metalloproteinases (MMPs), we tested if infusing TNFα (200 ng/kg/day) in day-14 pregnant (Preg) rats causes MMP imbalance and collagen accumulation, and if infusing TNFα decoy receptor Etanercept (0.4 mg/kg/day) in HTN-Preg rats with reduced uteroplacental perfusion pressure (RUPP) reverses MMP imbalance and collagen accumulation. On gestational day-19, blood pressure (BP) was higher in Preg + TNFα and RUPP vs Preg rats, and restored in RUPP + Etanercept rats. Gelatin zymography and Western blots revealed decreases in MMP-2 and MMP-9 and increases in MMP-1 and MMP-7 in aorta, uterus and placenta of Preg + TNFα and RUPP, that were reversed in RUPP + Etanercept rats. Collagen-I and IV were abundant in Preg + TNFα and RUPP, and were decreased in RUPP + Etanercept rats. The litter size, uterine, placenta, and pup weight were markedly reduced in RUPP, insignificantly reduced in Preg + TNFα, and slightly improved in RUPP + Etanercept rats. Thus TNFα blockade reverses the decreases in vascular and uteroplacental MMP-2 and MMP-9, and the increases in MMP-1, MMP-7 and accumulation of collagen-I and IV induced by placental ischemia and TNFα in HTN-Preg rats. Targeting TNFα using cytokine antagonists, or MMPs using MMP modulators could rectify MMP imbalance and collagen accumulation, restore vascular and uteroplacental remodeling, and improve BP in HTN-Preg and preeclampsia.

Characterization of Glutathione Peroxidase 4 in Rat Oocytes, Preimplantation Embryos, and Selected Maternal Tissues during Early Development and Implantation.

This study aimed to describe glutathione peroxidase 4 (GPx4) in rat oocytes, preimplantation embryos, and female genital organs. After copulation, Sprague Dawley female rats were euthanized with anesthetic on the first (D1), third (D3), and fifth days of pregnancy (D5). Ovaries, oviducts, and uterine horns were removed, and oocytes and preimplantation embryos were obtained. Immunohistochemical, immunofluorescent, and Western blot methods were employed. Using immunofluorescence, we detected GPx4 in both the oocytes and preimplantation embryos. Whereas in the oocytes, GPx4 was homogeneously diffused, in the blastomeres, granules were formed, and in the blastocysts, even clusters were present mainly around the cell nuclei. Employing immunohistochemistry, we detected GPx4 inside the ovary in the corpus luteum, stroma, follicles, and blood vessels. In the oviduct, the enzyme was present in the epithelium, stroma, blood vessels, and smooth muscles. In the uterus, GPx4 was found in the endometrium, myometrium, blood vessels, and stroma. Moreover, we observed GPx4 positive granules in the uterine gland epithelium on D1 and D3 and cytoplasm of fibroblasts forming in the decidua on D5. Western blot showed the highest GPx4 levels in the uterus and the lowest levels in the ovary. Our results show that the GPx4 is necessary as early as in the preimplantation development of a new individual because we detected it in an unfertilized oocyte in a blastocyst and not only after implantation, as was previously thought.

Effects of diabetes on nitric oxide synthase in rat uterus.

Diabetes mellitus (DM) is a common metabolic disorder with complications including nephropathy, cardiomyopathy, neuropathy and infertility. We investigated nitric oxide synthase (NOS) expression in uterine tissue of diabetic rats. The rats were assigned randomly to four groups of ten: group C, control; group 1, diabetic for 1 month; group 2, diabetic for 2 months; group 3, diabetic for 3 months. DM was induced by streptozotocin injection. nNOS, iNOS, eNOS expressions and TUNEL staining were assessed in uterine tissue and luteinizing hormone (LH), follicle stimulating hormone (FSH) and estrogen were measured in blood samples. The uterine epithelium, connective tissue of the endometrium, myometrium wall thickness and number of apoptotic cells were decreased in groups 1 - 3 compared to group C. nNOS and eNOS expression was increased in diabetic groups, but iNOS expression was similar to group 1. FSH was increased in group 2, but serum LH and estrogen levels were unchanged among groups. DM damages uterine tissue, and NOS, especially nNOS and eNOS, contributes to this damage.

Immunohistochemical determination of mTOR pathway molecules in ovaries and uterus in rat estrous cycle stages.

mTOR is a member of the PI3K/Akt/mTOR signaling pathway that participates in cell growth, proliferation, protein synthesis, transcription, angiogenesis, apoptosis and autophagy. mTOR and MAPK pahways are two important key signal pathways which are related to each other. We investigated the role of mTOR and other signaling molecules in rat ovaries and uteruses in stages of the estrous cycle. Young adult female rats were divided into four groups as proestrous, estrous, metestrous and diestrous according to vaginal smears. Immunohistochemical staining of mTORC1, IGF1, PI3K, pAKT1/2/3, ERK1 and pERK1/2 was performed and pAKT1/2/3 and ERK1 were also analyzed using western blotting on ovarian and uterine tissue samples. According to our results, PI3K/Akt/mTOR and ERK/pERK showed an increase in the rat ovulation period. When all the groups were evaluated the immunoreactivities for all of the antibodies were detected in the oocytes, granulosa and theca cells, corpus luteum and stroma of ovary and lamina propria, surface and glandular epithelium of uterus with the strongest observed with anti-ERK1 antibody and then with a decreasing trend with anti-mTORC1, anti-pAkt1/2/3, anti-IGF1, anti-PI3K and anti-pERK1/2 antibodies in the proestrus and estrus stages. Differently from other parts of the ovary, highest antibody expression in the corpus luteum was observed in the metestrous stage. Moreover, the existence of pAKT1/2/3 and ERK1 proteins was confirmed with the Western blotting technique. We suggest that mTOR and mTOR-related ERK signaling molecules may participate in the rat ovulation process.

Endometritis in the bitch: Immunohistochemical localization of cyclooxygenase 2.

Background: In several mammals, subfertility or infertility associated with endometritis was reported. Although there have been studies about endometritis in bitches, the pathophysiological mechanisms are not completely known. Aim: This study aimed to evaluate the immunohistochemical expression of Cyclooxygenase 2 (COX2) in clinically healthy bitches with normal uterine tissue and bitches with endometritis. Methods: Forty-eight mixed breed bitches in diestrus were used. Uterine biopsies were collected for diagnosis [normal endometrium (n = 15; NE), cystic endometrial hyperplasia (n = 1), atrophy (n= 2), acute endometritis (n = 9; AE), subacute endometritis (n = 7; SE), and chronic endometritis (n = 14; CE)]. Immunostaining and quantification of positively stained cells was performed on full-thickness uterine biopsies. Data were analyzed by the GLIMMIX procedure of SAS. Results: COX2 immunostaining was scattered and restricted to cells in the stroma in bitches with NE. However, in bitches with endometritis, strong staining was observed in the luminal epithelium, glandular epithelium, and stromal cells. Staining was also observed in inflammatory cells localized in the stroma as well as inside of the glands. The percentage of COX2 positive stromal cells in bitches with AE, SE, and CE was significantly higher compared with NE (p < 0.005). In addition, the percentage of COX2 positive stromal cells in bitches with SE, and CE was significantly lower compared with AE (p < 0.003). Conclusion: COX2 could be involved in the pathophysiological mechanisms producing endometritis without the presence of cystic endometrial hyperplasia in bitches. However, further researches on this topic are required.

Calliandra portoricensis ameliorates ovarian and uterine oxido-inflammatory responses in N-methyl-N-nitrosourea and benzo[a]pyrene-treated rats.

IMPACT STATEMENT: Infertility resulting from reproductive impairment is traumatic in families. Exposure to chemicals may play insidious roles not easily connected to infertility. We examined benzo[a]pyrene (BaP), and N-methyl nitrosourea (NMU)-induced ovarian and uterine toxicity and the role of Calliandra portoricensis in mitigating toxicity. In a bid to illuminate folk medical claims cloaked in mystery, unearthing lost knowledge, advance natural chemopreventive agents, and report new evidence lacking in the literature attributed to CP. Although CP is known to exhibit anticonvulsant, antidiarrheal, antipyretic, antirheumatic, and analgesic effects in humans, its possible roles for mitigating toxicity stemming from inadvertent chemical exposures are reported here. Our findings affirm and further show that CP abates toxic response incumbent on oxidative damage and inflammatory responses associated with NMU and BaP exposure. Development of phytochemical derived from CP may serve as a potential natural therapy against chemical toxicities in individuals inadvertently exposed, and promote human health and reproductive satiety.

ER-depletion lowering the 'hypothalamus-uterus-kidney' axis functions by perturbing the renal ERß/Ptgds signalling pathway.

Researchers have long assumed that systematic estrogen fading might contribute to the sustained progression of menopausal degenerate syndromes, although definitive evidence has not been presented. Whether such findings represent a causal contribution or are the result of opportunistic messengers sent from the reproductive system to the brain is also a vital question. We constructed a multiscale network of the ovariectomy (OVX) induced estrogen receptors depletion (ER-depletion) model and integrated targeted proteomic, targeted lipidomic, cytochemical, and histopathological data across three tissues from the ovariectomy rodent model. We found that compared to control rats, OVX rats showed increased renal and uterine prostaglandin D2 synthase (Ptgds) expression and decreased hypothalamic Ptgds expression, abnormal Ptgds metabolites, the degenerate renal function profiles and decreased cognitive ability (learning and memory) in Morris water maze test. Importantly, we observed a regulatory relationship among ER (particularly ERß), the degree of the pathological phenotype, learning behavior test and the 'hypothalamus-uterus-kidney (HUK) axis functions. Collectively, this study elucidates that ER depletion promoted HUK aging is mostly attributed to a renal ERß/Ptgds signalling imbalance.

Development and Application of the Metalloprotease Activity Multiplexed Bead-Based Immunoassay (MAMBI).

Metalloproteinases (MMPs) are zinc-dependent endopeptidases that cleave various proteins to regulate normal and diseased cellular functions, and as such, they play significant roles in human tissue development, homeostasis, and the pathogenesis of many diseases, including cancers, endometriosis, arthritis, etc. Most MMPs are produced as zymogenic latent enzymes that must be cleaved to activate their catalytic regions, and localized endogenous protein inhibitors further regulate activity. Accordingly, they operate within recursive networks to degrade extracellular matrix proteins and regulate cell signaling by cleaving growth factors and receptors at the cell surface and in the local pericellular environment. Thus, high-resolution information about the concentrations of specific active MMPs, revealing their intricate regulatory networks, may improve disease diagnosis and treatment. Here, we introduce a new and readily mastered method for measuring MMP activities in a multiplex fashion. We integrate aspects of activity-based enzyme labeling with commercial high-throughput, multiplexed protein quantification to yield the metalloproteinase activity multiplexed bead-based immunoassay (MAMBI). Assays of recombinant active MMP-1, -2, -3, -7, -8, -9, -12, and -13 establish the sensitivity and selectivity of MAMBI detection. Levels of active native MMPs are similarly characterized in conditioned cell culture medium, menstrual effluent, and uterine tissue. In a single MAMBI (5 µL), we achieve sensitivities equal to those from leading single-plex MMP activity detection strategies (e.g., 10-15 M for MMP-1). We also demonstrate high-throughput inhibitor screening via the MAMBI approach in complex, patient-derived samples.

Can the negative effects of ketamine abuse on female genital organs be prevented by nimesulide? An experimental study.

The objective of this study is to investigate the effects of nimesulide on ketamine-induced ovarian and uterine toxicity by biochemical and histopathological examinations. Ketamine is an anesthetic agent whose use leads to overproduction of catecholamines. Nimesulide is a cyclooxygenase-2 inhibitor, which has also been reported to exert a significant antioxidant effect. Wistar albino female rats were randomly divided into three groups as follows: ketamine group (60 mg/kg), ketamine (60 mg/kg) + nimesulide (50 mg/kg) group, and a healthy control group. Then, the biochemical levels and histopathological findings in the ovaries and uteri of the rats were examined for malondialdehyde, myeloperoxidase, total glutathione and superoxide dismutase. The study demonstrated that, in the uterine and ovarian tissues of rats that have been administered ketamine, there was a decrease in the levels of total glutathione and superoxide dismutase, while malondialdehyde and myeloperoxidase was increased: however it was observed that these ratios were reversed in the ketamine+nimesulide group. It was also proved that the negative effects of ketamine can be corrected with nimesulide when the myometrial and endometrial thicknesses are compared. Antioxidants such as nimesulide may protect against the damage caused by ketamine to the genital organs in young women.

Analysis of Vascular Hydrogen Sulfide Biosynthesis.

With potent vasodilatory and pro-angiogenic properties, hydrogen sulfide (H2S) is now accepted as the third gasotransmitter after nitric oxide (NO) and carbon monoxide. Endogenous H2S is mainly synthesized by cystathionine ß-synthase (CBS) and cystathionine γ-lyase (CSE). Akin to previous studies showing hormonal regulation of NO biosynthesis, we first reported that uterine and systemic artery H2S biosynthesis is regulated by exogenous estrogens in an ovariectomized sheep model of estrogen replacement therapy, specifically stimulating CBS, but not CSE, expression, in uterine (UA) and mesenteric (MA), but not carotid (CA), arteries in ovariectomized nonpregnant sheep. We have found significantly elevated H2S biosynthesis due to CBS upregulation under estrogen-dominant physiological states, the proliferative phase of menstrual cycle and pregnancy in primary human UAs. Our studies have pioneered the role of H2S biology in uterine hemodynamics regulation although there is still much that needs to be learned before a thorough elucidation of a role that H2S plays in normal physiology of uterine hemodynamics and its dysregulation under pregnancy complications can be determined. In this chapter we describe a series of methods that we have optimized for analyzing vascular H2S biosynthesis, including (1) real-time quantitative PCR (qPCR) for assessing tissue and cellular levels of CBS and CSE mRNAs, (2) immunoblotting for assessing CBS and CSE proteins, (3) semiquantitative immunofluorescence microscopy to specifically localize CBS and CSE proteins on vascular wall and to quantify their cellular expression levels, and (4) methylene blue assay for assessing H2S production in the presence of selective CBS and CSE inhibitors.

The histone methyltransferase EZH2 is required for normal uterine development and function in mice†.

Enhancer of zeste homolog 2 (EZH2) is a rate-limiting catalytic subunit of a histone methyltransferase, polycomb repressive complex, which silences gene activity through the repressive histone mark H3K27me3. EZH2 is critical for epigenetic effects of early estrogen treatment, and may be involved in uterine development and pathologies. We investigated EZH2 expression, regulation, and its role in uterine development/function. Uterine epithelial EZH2 expression was associated with proliferation and was high neonatally then declined by weaning. Pre-weaning uterine EZH2 expression was comparable in wild-type and estrogen receptor 1 knockout mice, showing neonatal EZH2 expression is ESR1 independent. Epithelial EZH2 was upregulated by 17ß-estradiol (E2) and inhibited by progesterone in adult uteri from ovariectomized mice. To investigate the uterine role of EZH2, we developed a EZH2 conditional knockout (Ezh2cKO) mouse using a cre recombinase driven by the progesterone receptor (Pgr) promoter that produced Ezh2cKO mice lacking EZH2 in Pgr-expressing tissues (e.g. uterus, mammary glands). In Ezh2cKO uteri, EZH2 was deleted neonatally. These uteri had reduced H3K27me3, were larger than WT, and showed adult cystic endometrial hyperplasia. Ovary-independent uterine epithelial proliferation and increased numbers of highly proliferative uterine glands were seen in adult Ezh2cKO mice. Female Ezh2cKO mice were initially subfertile, and then became infertile by 9 months. Mammary gland development in Ezh2cKO mice was inhibited. In summary, uterine EZH2 expression is developmentally and hormonally regulated, and its loss causes aberrant uterine epithelial proliferation, uterine hypertrophy, and cystic endometrial hyperplasia, indicating a critical role in uterine development and function.

Class II PI3Ks α and ß Are Required for Rho-Dependent Uterine Smooth Muscle Contraction and Parturition in Mice.

Class II phosphoinositide 3-kinases (PI3Ks), PI3K-C2α and PI3K-C2ß, are highly homologous and distinct from class I and class III PI3Ks in catalytic products and domain structures. In contrast to class I and class III PI3Ks, physiological roles of PI3K-C2α and PI3K-C2ß are not fully understood. Because we previously demonstrated that PI3K-C2α is involved in vascular smooth muscle contraction, we studied the phenotypes of smooth muscle-specific knockout (KO) mice of PI3K-C2α and PI3K-C2ß. The pup numbers born from single PI3K-C2α-KO and single PI3K-C2ß-KO mothers were similar to those of control mothers, but those from double KO (DKO) mothers were smaller compared with control mice. However, the number of intrauterine fetuses in pregnant DKO mothers was similar to that in control mice. Both spontaneous and oxytocin-induced contraction of isolated uterine smooth muscle (USM) strips was diminished in DKO mice but not in either of the single KO mice, compared with control mice. Furthermore, contraction of USM of DKO mice was less sensitive to a Rho kinase inhibitor. Mechanistically, the extent of oxytocin-induced myosin light chain phosphorylation was greatly reduced in USM from DKO mice compared with control mice. The oxytocin-induced rise in the intracellular Ca2+ concentration in USM was similar in DKO and control mice. However, Rho activation in the intracellular compartment was substantially attenuated in DKO mice compared with control mice, as evaluated by fluorescence resonance energy transfer imaging technique. These data indicate that both PI3K-C2α and PI3K-C2ß are required for normal USM contraction and parturition mainly through their involvement in Rho activation.

Differential Regulation of Myosin Regulatory Light Chain Phosphorylation by Protein Kinase C Isozymes in Human Uterine Myocytes.

BACKGROUND: Preterm birth is the most common cause of neonatal morbidity and mortality and a common precedent to lifelong disability. Current treatment has minimal efficacy. OBJECTIVE: We assessed the role of isozymes of the protein kinase C (PKC) family in regulating the phosphorylation of myosin regulatory light chains (RLCs), which regulate uterine contractility. We also explored the mechanisms through which these isozymes function. STUDY DESIGN: We used a previously characterized and validated quantitative in-cell Western (ICW) assay to measure site-specific phosphorylations on myosin RLC and CPI-17. Cultures of human uterine myocytes (hUM) were treated with the potent contractile stimulant oxytocin to induce uterine contractility or a pharmacological mimic of diacyl-glycerol to stimulate the conventional and novel isozymes of the PKC family. Combinations of isozyme-selective inhibitors were used to determine the effects of the conventional and novel classes of isozymes. RESULTS: Stimulation of PKC using phospho-dibutyrate caused immediate, concentration-dependent inhibition of uterine activity ex vivo. Using the ICW assay with hUM, the oxytocin-stimulated increase in the pro-contractile phosphorylations of myosin RLCs at serine19 and threonine18 was completely inhibited by prior treatment with phorbol-12-myristate-13-acetate, which stimulates both convention and novel classes of isozymes. Our results suggest that the conventional class of isozymes cause a reduction in phosphorylations at serine19 and threonine18 by reducing activity of myosin light chain kinase. The novel class of isozymes has 2 mechanisms of action: the first is activation of CPI-17 through phosphorylation at threonine38, which results in reduced activity of myosin light chain phosphatase and increased levels of activated myosin RLC; the second is increased phosphorylation of the N-terminal region of myosin RLC. CONCLUSIONS: Specific agonists for the conventional isozymes or inhibitors of the novel isozymes of the PKC family could be useful pharmacological agents for regulation of uterine activity.

The sialyltransferase ST3Gal3 facilitates the receptivity of the uterine endometrium in vitro and in vivo.

The receptive uterine endometrium specifically expresses certain glycosyltransferases, and the corresponding oligosaccharides play important roles in accepting the embryo. The sialyltransferase ß-galactoside-α2,3-sialyltransferase III (ST3Gal3) is the key enzyme responsible for sialyl Lewis X (sLeX) oligosaccharide biosynthesis, but the expression and function of ST3Gal3 in the receptive endometrium is still elusive. Here, we found that human endometrial tissues at secretory phase expressed a 4-fold higher ST3Gal3 level relative to the tissues at proliferative phase. Meanwhile, downregulation of ST3Gal3 or sLeX epitope blockage significantly impaired the receptive ability of human endometrial RL95-2 cells to trophoblastic cells in vitro and inhibited implantation in pregnant mice. This study suggests that ST3Gal3 facilitates endometrial receptivity through increasing sLeX oligosaccharide, which gives a better understanding of the glycobiology of implantation.

Zingerone ameliorates cisplatin-induced ovarian and uterine toxicity via suppression of sex hormone imbalances, oxidative stress, inflammation and apoptosis in female wistar rats.

Cisplatin (CP) is a widely used chemotherapeutic drug, effective against a variety of solid tumours, though its utility is limited due to its multiple organ toxicity. Zingerone (ZO), one of the most important components of dry ginger root, has several pharmacological activities, such as antioxidant, anti-inflammatory and anti-apoptotic properties. This study aimed to investigate the ameliorative effect of ZO on CP-induced ovarian and uterine toxicity in female rats. The rats were subjected to a prophylactic oral treatment of ZO (25 and 50 mg/kg body weight) for seven days to measure the protective effect against ovarian and uterine toxicity induced by a single (i.p.) of CP (7 mg/kg body weight) on the first day whereas the rats were sacrificed on the eighth day. The results showed that ZO decreased the serum FSH hormone level, increased the serum E2 hormone level, and also maintained the ovarian and uterine histological architecture and integrity. In addition, ZO obviously increased the measured activity of antioxidant enzymes (SOD, CAT and GPx) and the GSH content, and significantly reduced MDA levels. ZO was able to reduce the levels of the inflammatory markers NF-κB, TNF-α, IL-1ß, IL-6, COX-2 and iNOS in CP-induced ovarian and uterine damage. It also inhibited apoptosis and reduced oxidative DNA damage markers by the downregulation of caspase-3 and 8-OHdG expression coupled with an upregulated Bcl-2 level. The results indicate that ZO may be beneficial in ameliorating CP-induced oxidative stress, sex hormone imbalances, inflammation and apoptosis in ovarian and uterine tissues of female rats.

Endocannabinoids as endometrial inflammatory markers in lactating Holstein cows.

The objective of this study was to consider endocannabinoid system as inflammatory markers in bovine endometrium to better understand the role of this system in regulating many of the functions that are related to inflammatory condition. At day 26 post-partum, fourteen cows were divided into two groups depending on the inflammatory condition: 1- subclinical endometritis (n = 7, with purulent or mucopurulent uterine discharge detectable in the vagina) and 2- healthy (n = 7, No (muco)) purulent discharge. Blood samples were collected at 26 and 30 days relative to calving to determine plasma tumour necrosis factor (TNF) and lipopolysaccharide-binding protein (LBP) concentrations; moreover, uterine biopsy was carried out on day 26 post-partum to measure mRNA abundance of TNF, interleukin-1B (IL1B), interleukin-6 (IL-6), C-X-C motif chemokine ligand 8 (CXCL8), endocannabinoid receptor (CNR2), N-acyl phosphatidylethanolamine phospholipase D (NAPEPLD), fatty acid amide hydrolase (FAAH), N-acylethanolamine acid amidase (NAAA) and monoglyceride lipase (MGLL) by real-time PCR. Results showed mean plasma concentrations of TNF and LBP were lower in healthy cows compared to subclinical endometritis cows (p < .05). Relative mRNA expression for NAAA and FAAH was decreased (p < .05), and relative mRNA expression for CNR2 and NAPEPLD increased in cows with subclinical endometritis compared to healthy cows. In conclusion, relative mRNA expression of TNF, IL1B and CXCL8 and plasma concentration of LBP increased during inflammatory condition along with decreased endocannabinoids hydrolyzing enzyme (NAAA and FAAH), increased enzymes that synthesize endocannabinoids (NAPEPLD) and relative gene expression of the endocannabinoid receptor; together, these contribute to increased endocannabinoids levels during inflammation. Overall, we provide evidence that endocannabinoid system is altered in endometrium tissue during inflammation through increased mRNA expression of CNR2 and synthesis enzyme and decreased mRNA expression of hydrolyzing enzymes interfere with pro-cytokine production and signalling, which may interfere with the onset and progression of inflammation.

Immunohistochemical Features of O6-Methylguanine-DNA Methyltransferase Expression during Ovarian Endometriosis.

A comparative immunohistochemical study for the expression of O6-methylguanine-DNA methyltransferase (MGMT) was performed in tissues of the eutopic endometrium and ovarian endometriosis. The highest level of MGMT expression in eutopic endometrial tissue was observed in epitheliocyte nuclei during the proliferative phase. In regions of endometriosis the expression of MGMT in epitheliocyte nuclei was shown to increase during stages I and II, but decreased in stages III and IV. The progression of endometriosis was accompanied by a gradual increase of study parameters in the nuclei and cytoplasm of stromal cells. These changes reflect the impairment of DNA reparation, which probably serves as a stage in the development and progression of endometriosis.

Elevated Levels of ADMA Are Associated with Lower DDAH2 and Higher PRMT1 in LPS-Induced Endometritis Rats.

Chronic endometritis is a continuous inflammation of uterine endometrium. Recent research has shown that higher asymmetric dimethylarginine (ADMA) levels contribute to endothelial dysfunction. In the present study, we tested whether there is a correlation between endometritis and ADMA in LPS-induced endometritis rat and the mechanisms involved. Thirty-six rats were divided into two groups: blank control group and rat model of endometritis group. The entire infused uterus were removed to observe the changes of histopathology, production of myeloperoxidase (MPO), tumor necrosis factor-α (TNF-α), interleukin (IL)-6, 8-isoprostane, and reactive oxygen species (ROS), and gene expression of dimethylarginine dimethylaminohydrolase 2 (DDAH2), protein-methyl transferase 1 (PRMT1), TNF-α, and IL-6. In endometritis rat group, characteristic histopathologic changes in uteri were observed. The uterine 8-isoprostane, ROS, MPO activity, IL-6 and TNF-α concentrations, PRMT1, IL-6, and TNF-α expressions were significantly elevated, and DDAH2 expression was notably reduced in endometritis group compared with control group. The present findings suggest that elevated levels of ADMA are associated with lower DDAH2 and higher PRMT1 in LPS-induced endometritis rat.