PGF2 Research Articles

Unraveling the role of lipid droplets and perilipin 2 in bovine luteal cells.

Steroidogenic tissues contain cytosolic lipid droplets that are important for steroidogenesis. Perilipin 2 (PLIN2), a structural coat protein located on the surface of lipid droplets in mammalian cells, plays a crucial role in regulating lipid droplet formation and contributing to various cellular processes such as lipid storage and energy homeostasis. Herein, we examine the role that PLIN2 plays in regulating progesterone synthesis in the bovine corpus luteum. Utilizing gene array databases and Western blotting, we have delineated the expression pattern of PLIN2 throughout the follicular to luteal transition. Our findings reveal the presence of PLIN2 in both ovarian follicular and steroidogenic luteal cells, demonstrating an increase in its levels as follicular cells transition into the luteal phase. Moreover, the depletion of PLIN2 via siRNA enhanced progesterone production in small luteal cells, whereas adenovirus-mediated overexpression of both PLIN2 and Perilipin 3 (PLIN3) induced an increase in cytosolic lipid droplet accumulation and decreased hormone-induced progesterone synthesis in these cells. Lastly, invivo administration of the luteolytic hormone prostaglandin F2α resulted in an upregulation of PLIN2 mRNA and protein expression, accompanied by a decline in serum progesterone. Our findings highlight the pivotal role of PLIN2 in regulating progesterone synthesis in the bovine corpus luteum, as supported by its dynamic expression pattern during the follicular to luteal transition and its responsiveness to luteotropic and luteolytic hormones. We suggest PLIN2 as a potential therapeutic target for modulating luteal function.

The regulation of the expression of prokineticin 1 and its receptors and its mechanism of action in the porcine corpus luteum

Prokineticin 1 (PROK1) is an important factor in pregnancy establishment in pigs, acting at the embryo–maternal interface and the corpus luteum (CL). Estradiol-17β (E2) is the primary pregnancy recognition signal in pigs, and its effects are augmented by luteotropic prostaglandin E2 (PGE2). On the contrary, prostaglandin F2α (PGF2α) exerts mainly a luteolytic effect. The present study aimed to elucidate whether E2, PGE2, and PGF2α regulate the expression of PROK1 and its receptors in the porcine CL and to determine the PROK1 effect on luteal endothelial cells and pathways that may be involved in this regulation. The effects of E2, PGE2, and PGF2α on the expressions of PROK1 and its receptors in the CL were studied using an in vitro model of ultrathin luteal tissue explants model. Additionally, the effects of E2 and PGE2 on the PROK1 system were determined using an in vivo approach, in which the hormones were administered into the uterine lumen to imitate their secretion by embryos. Endothelial cell proliferation was measured using the colorimetric method. E2 acting via estrogen receptors simulated the mRNA and protein expressions of PROK1 and PROKR1 in CL explants in vitro (p < 0.05). The simultaneous action of E2 with PGE2 enhanced the expression of luteal PROK1 mRNA in vitro (p < 0.05). Estradiol-17β acting alone significantly increased PROK1 mRNA levels in vivo, whereas E2 simultaneously administered with PGE2 significantly elevated the PROK1 mRNA expression and PROKR1 mRNA and protein contents in CLs adjacent to uterine horns receiving hormonal infusion compared with CLs adjacent to placebo-treated uterine horns (p < 0.01). The PROK1 protein expression was significantly higher in the CLs of pigs treated with E2, PGE2, and E2 together with PGE2 than in the control group. PGF2α increased the PROK1 mRNA content in CLs on days 12 and 14 of the estrous cycle (p < 0.05). The expression of PROKR2 at the mRNA and protein levels remained unchanged in response to in vitro and in vivo treatments. PROK1 stimulated the proliferation of luteal endothelial cells by activating the MAPK, AKT, and mTOR pathways (p < 0.05). In summary, the luteal expressions of PROK1 and PROKR1 in early pregnancy are regulated by E2 and PGE2. PROK1 stimulates luteal angiogenesis by activating the MAPK, AKT, and mTOR pathways. The regulation of luteal PROK1 expression by PGF2α indicates PROK1's putative role during luteolysis. We conclude that PROK1-PROKR1 signaling supports luteal function during CL rescue in pregnancy in pigs.

Pregnancy and Luteal Responses to Embryo Reinsertion following Embryo Flushing in Donor Mares.

The effect of embryo reinsertion immediately after embryo flushing was studied. In Experiment 1, eight mares were used during 32 cycles (8 cycles in each group). For the first two groups, inseminated mares were flushed 8 days after ovulation and prostaglandin F2α was not administered: in group EF-ET (embryo flushing and embryo transfer) the embryo was reinserted in the same donor mare, while in the EF group, no further procedure was performed. In the third group (ET), non-inseminated mares (recipients) received a Day 8 embryo. Progesterone concentration was measured before EF/ET and 72 h after in the three groups. In Experiment 2, twelve mares were used during 17 cycles in two groups, EF-ET (n = 11) and ET (n = 6), as in Experiment 1, except that every mare was flushed 24 h after embryo transfer to retrieve the embryo. Fewer pregnancies resulted after transfer in EF-ET cycles (0/8, 0%) than in the ET group (6/8, 75%). Progesterone concentration decreased significantly (p = 0.05) 72 h after EF-ET but not in EF or ET cycles (p > 0.1). Three mares from the EF-ET showed full luteolysis and signs of endometritis. In Experiment 2, more (5/6; p = 0.08) grade 1 embryos were recovered in the ET compared to the EF-ET group (3/7); 4 embryos were graded 3-4 (were broken or had signs of degeneration) in the EF-ET group but none in the ET group. In both groups, capsule fragments were obtained as indicative of the presence of a recently destroyed embryo in the EF-ET (n = 3) and ET (n = 1) groups. Positive bacterial cultures were obtained in 2/11 and 1/6 embryo flushes from the EF-ET and ET groups, respectively.

Insights into the role of PGF2α in canine periparturient myometrium.

Parturition in dogs is subjected to complex hormonal regulation, with the involvement of prostaglandin F2α (PGF2α) still not fully understood. To investigate uterine inertia (UI), the most prevalent maternal reason for dystocia in the bitch, a better understanding of undisturbed uterine, especially myometrial function, is crucial. Our aim was to gain deeper insights into the role of PGF2α in the canine parturient myometrium. Uterine biopsies were obtained during medically indicated cesarean sections. To test for stimulatory effects of PGF2α in vitro, circular and longitudinal myometrial layer tissue strips were challenged with 50pM, 0.5µM, and 50µM PGF2α. Prostaglandin-endoperoxide synthase 2 (PTGS2) and PGF2α-receptor (PTGFR) mRNA expressions were compared between primary UI (PUI) and obstructive dystocia (OD) samples in isolated parturient myometrium. PTGFR protein expression was assessed in full thickness uterine samples. PGF2α concentrations were analyzed in canine interplacental tissue around term. In the organ bath, the contractile response to PGF2α was limited to the circular layer at the highest dosage. Correspondingly, PTGFR immunohistochemical staining was significantly stronger in the circular layer (p ≤ 0.01). PTGS2 gene expression did not differ between PUI and OD, whereas PTGFR gene expression could not be quantified. Local uterine PGF2α concentrations correlated negatively with serum P4 levels and were the highest during prepartum luteolysis while being significantly lower in PUI. Conclusively, despite the significant increase in local PGF2α concentrations at birth, confirming the interplacental tissue as a production site, our results suggest that PGF2α might affect uterine contractility during labor, mainly indirectly.

Pregnane X receptor (PXR) deficiency promotes hepatocarcinogenesis via induction of Akr1c18 expression and prostaglandin F2α (PGF2α) levels

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Pregnane X receptor (PXR), a xenobiotic-sensing nuclear receptor, plays a critical role in the metabolism of endogenous and exogenous substances in the liver. Here, we investigate whether PXR plays a role in pathogenesis of HCC. We show that liver tumors were developed in diethylnitrosamine (DEN)-treated in PXR knockout (KO) mice. Hepatic levels of prostaglandin F2α (PGF2α) and aldo–keto reductase family 1 member C18 (Akr1c18), a prostaglandin synthase of catalyzing reduction of PGH2 to PGF2α, were significantly elevated in DEN-treated PXR KO mice. Hepatic mRNA levels of alpha fetoprotein (AFP), cyclin D1 (Ccnd1), fibroblast growth factor 21 (FGF21), and inflammatory cytokine interleukin 6 (IL-6) were significantly increased in DEN-treated PXR KO mice. Other members of Akr1c family, liver metabolizing enzymes including Cyp1a2, Cyp2b10 and Cyp3a11, and bile acid synthesis enzyme Cyp7a1 mRNA levels were significantly decreased in DEN-treated PXR KO mice. Our findings revealed that PXR deficiency promoted DEN-induced HCC in mice via induction of Akr1c18 expression and PGF2α levels and the increased PGF2α levels synthetized by Akr1c18 enhanced hepatocytes proliferation and induced inflammatory cytokine production, which accelerated liver tumor development after DEN treatment, suggesting that PXR deficiency may create a microenvironment that is more prone to DEN-induced liver tumors and targeting PXR and Akr1c18 to reduce PGF2α biosynthesis may be a potential and novel therapeutic strategy for HCC.

Metabolomic analysis reveals the molecular mechanism related to leg abnormality in broilers

AbstractRapid body weight gain in broilers overloads the metabolic system of the organism, resulting in leg abnormalities, which seriously affects animal welfare and industry economics. In this study, broilers with normal and deformed leg bones were examined. Serum biochemical indices showed that the serum calcium to phosphorus ratio was extremely decreased in leg deformed group. In addition, abnormal serum lipid levels suggested a disruption in lipid metabolism. Based on widely targeted metabonomic analysis of serum and cartilage tissues, a total of nine differential metabolites (DMs) significantly associated with leg abnormalities and serum calcium and phosphorus levels were screened, including carnitine C16:0, carnitine C18:1, 3‐hydroxymethyl‐L‐tyrosine, cis‐4‐hydroxy‐D‐proline, cis‐L‐3‐hydroxyproline, trans‐4‐hydroxy‐L‐proline, and so on. Pathway analysis revealed that fatty acid degradation and arachidonic acid metabolism were enriched. Analysis of DMs in these two pathways showed that prostaglandin D2, prostaglandin J2, prostaglandin A2, 15‐keto prostaglandin F2α, and Δ12‐prostaglandin J2 significantly differed between the normal and abnormal groups. It was hypothesized that these important metabolic pathways and metabolites were involved in the metabolic regulation of leg abnormalities.

Prostaglandin F2α treatment does not hasten ovulation in weaned sows

This study evaluated the efficiency of prostaglandin F2α (PGF) to hasten ovulation in weaned sows. In experiment I, weaned sows detected in estrus (0 h) received: no hormone (Control; n = 56); 0.5 mg PGF IM at 0 h and 2 h (PGF0; n = 56); or 0.5 mg PGF IM at 24 h and 26 h (PGF24; n = 55). In experiment II, weaned sows that did not express estrus signs until 72 h after weaning (0 h) were assigned to: no hormone (Control; n = 45); 10 µg buserelin acetate IM at 0 h (Buserelin; n = 43); 0.5 mg PGF IM at 34 h and 36 h (PGF; n = 44); or 10 µg buserelin acetate IM at 0 h plus 0.5 mg PGF IM at 34 h and 36 h (Buserelin + PGF; n = 45). In experiment I, no effect of PGF on the interval treatment onset to ovulation was observed (P > 0.05), and no treatment effect was observed on the relative or cumulative proportion of females that ovulated post-treatment onset (P > 0.05). In experiment II, treatment onset to ovulation interval was shorter for Buserelin group than for PGF group (P < 0.05), and a higher cumulative percentage of Buserelin treated sows ovulated up to 48 h compared to PGF and Control groups (P < 0.01), with no differences from Buserelin + PGF. Treatments did not affect total number of piglets born in both experiments (P > 0.05). In conclusion, PGF did not hasten ovulation timing or affect litter size in weaned sows.

Serum Metabolomic Analysis of Synchronous Estrus in Yaks Based on UPLC-Q-TOF MS Technology.

The yak is a unique species of livestock found in the Qinghai-Tibet Plateau and its surrounding areas. Due to factors such as late sexual maturity and a low rate of estrus, its reproductive efficiency is relatively low. The process of estrus synchronization in yaks plays a crucial role in enhancing their reproductive success and ensuring the continuation of their species. In order to clarify the characteristics of the serum metabolites of yak estrus synchronization, the yaks with inactive ovaries were compared with the estrus synchronization yaks. In this study, yaks were divided into the inactive ovaries group (IO), gonarelin-induced yak estrus group (GnRH), and chloprostenol sodium-induced yak estrus group (PGF). After the completion of the estrus synchronization treatment, blood samples were collected from the jugular veins of the non-estrus yaks in the control group and the yaks with obvious estrus characteristics in the GnRH and PGF groups. Metabolites were detected by ultra-high performance liquid chromatography-mass spectrometry, and differential metabolites were screened by multivariate statistical analysis. The results showed that a total of 70 significant differential metabolites were screened and identified in the GnRH vs. IO group, and 77 significant differential metabolites were screened and identified in the PGF vs. IO group. Compared with non-estrus yaks, 36 common significant differential metabolites were screened out after the induction of yak estrus by gonarelin (GnRH) and cloprostenol sodium (PGF), which were significantly enriched in signaling pathways such as the beta oxidation of very long chain fatty acids, bile acid biosynthesis, oxidation of branched chain fatty acids, steroidogenesis, steroid biosynthesis, and arginine and proline metabolism. This study analyzed the effects of gonadotropin releasing hormone (GnRH) and prostaglandin F (PGF) on the reproductive performance of yaks treated with estrus synchronization, which provides a theoretical basis for the optimization and application of yak estrus synchronization technology and promotes the healthy development of the yak industry.

PSIII-7 7&amp;7 Synch improved pregnancy rates in beef cows experiencing estrus over 24 h before fixed-time insemination

Abstract Our objectives were to compare estrus response and pregnancy rates between two different estrus synchronization protocols and between cows that experienced estrus more than 24 h before appointment breeding and those that experienced estrus less than 24 h before breeding. Over each of 2 yr, postpartum beef cows (n = 1,108) from two different locations were ranked by days postpartum and randomly selected to receive either; 1) 7-d CO-Synch + CIDR (CO-Synch, n = 547), or; 2) 7 &amp; 7 Synch (7&amp;7, n = 561). For the CO-Synch treatment, cows received a controlled internal drug release insert (CIDR; 1.38g progesterone) and 100 µg gonadotropin-releasing hormone (GnRH) i.m., followed in 7 d by CIDR removal and 25 mg prostaglandin F2alpha (PGF) i.m., followed in 60 to 66 h with AI and 100 µg GnRH i.m. For the 7&amp;7 Synch protocol, cows received a CIDR (1.38g progesterone) and 25 mg PGF i.m., followed in 7 d by 100 µg GnRH i.m., followed in 7 d by CIDR removal and 25 mg PGF i.m., followed in 60 to 66 h with AI and 100 µg GnRH i.m. Heat detection patches were applied at the time of CIDR removal to determine estrus response by the time of AI, with cows having patches ≥ 50% activated defined as being in estrus and cows with patches &amp;lt; 50% activated defined as not experiencing estrus. In yr 2, an additional heat detection was performed 24 h before breeding, at which time cows with ≥ 50% activated heat detection patches were defined as having an early estrus (i.e., estrus more than 24 h before breeding) and cows with activated patches first observed at the time of AI were defined as having an on-time estrus. Pregnancy status was determined via transrectal ultrasonography 35 d after AI. Data were analyzed using the GLIMMIX procedure of SAS. As expected, cows in the 7&amp;7 treatment had greater (P ≤ 0.005) estrus response and pregnancy rates than those in the CO-Synch treatment (83% vs. 62% and 65% vs. 55%, respectively). The proportion of cows experiencing early estrus was similar (P &amp;gt; 0.60) between treatments (20.4 and 22.9 for Co-Synch and 7&amp;7, respectively). Interestingly, pregnancy rate was impacted by a treatment × estrus timing interaction (P = 0.04), where cows in the Co-Synch treatment that experienced an early estrus (52.9%) had reduced pregnancy rates compared with 7&amp;7 cows that experienced early estrus (74.0%), Co-Synch cows that experienced on-time estrus (73.7%) and 7&amp;7 cows that experienced on-time estrus (70.5%). Our results indicate the 7&amp;7 Synch protocol can effectively increase pregnancy rates to fixed-time AI, and that pregnancy rates of cows experiencing early estrus are influenced by synchronization protocol.

242 Comparison of GnRH administration day in the 7&amp;7 Synch versus 8&amp;6 Synch Protocol for fixed-timed artificial insemination in beef heifers

Abstract The research aimed to investigate the impact of reducing the time interval for progesterone exposure on the ovulatory follicle just before performing fixed-timed artificial insemination (FTAI). This was achieved by adjusting the timing of administering a gonadotropin-releasing hormone agonist (GnRH; specifically, 100 µg gonadorelin, known as Cystorelin). The study assessed the effectiveness of two estrous synchronization protocols, the “7 &amp; 7 Synch” and a modified protocol, by examining estrus expression (EE) and the resulting pregnancy rates (PR) following FTAI. The research utilized frozen conventional Angus semen from Select Sires, Inc. (Plain City, OH), and involved 66 Angus-cross heifers from the beef cattle research unit near Fayetteville at the University of Arkansas. To ensure consistency, the heifers were divided into two treatment groups based on their cyclicity status (CYC) and age. CYC status was determined by assessing a reproductive tract score (RTS) 1 wk before the synchronization process. RTS scores ranged from 1 to 5, with RTS 1-3 indicating pre- or peripubertal status and scores of 4 and 5 indicating cycling. Heifers with an RTS of 1 and 2 were excluded from the study before synchronization commenced. Both treatment groups involved the insertion of a controlled internal drug-releasing device (CIDR; specifically, Eazi-breed, containing 1.38 g of progesterone) into the vagina on d -14. Simultaneously, a prostaglandin F2α analogue (PGF; 500 µg cloprostenol sodium, known as Synchsure) was administered. In the first treatment group (7&amp;7), GnRH was administered on d -7, while in the second group (8&amp;6), GnRH was given on d -6. In both cases, PGF was administered on d 0 when the CIDR was removed, precisely 72 ± 1 h before FTAI, along with another dose of GnRH. Estrus expression (EE) was assessed during FTAI by examining Estrotect patches (Rockway Inc., Spring Valley, WI). EE was considered present when a patch had 50% or more of its color rubbed off, and it was deemed absent when less than 50% of the color had worn off. Pregnancy rates (PR) were determined through ultrasound examination on d 55. EE and PR were analyzed by treatment using the GLIMMIX procedure on SAS 9.4 (SAS Institute Inc., Cary, NC). Statistical differences were declared at α ≤ 0.05 and tendencies declared between 0.05 &amp;lt; P ≤ 0.1. Heifers on the 8&amp;6-d protocol had greater rectal temperatures at breeding compared with 7&amp;7-d heifers (P &amp;lt; 0.0001). AI pregnancy rates were greater in heifers on the 8&amp;6-d protocol compared with the heifers on 7&amp;7-d protocol (P = 0.625) with average pregnancy rates of 39.4% and 30.3%, respectively. Overall, pregnancy rate was greater as well for the 8&amp;6-d heifers compared with the 7&amp;7-d heifers (P = 0.044), with mean overall pregnancy rates of 78.8% and 54.5%, respectively.

Oxytocin, prostaglandin F2α, and scopolamine for uterine involution of dairy cows.

The aim of the study was to compare the effect of three substances with ecbolic activity, Oxytocin, Prostaglandin F2α (PGF2α) and Scopolamine, on the uterine involution process in dairy cows and on the resumption of ovarian activity. Eighty bovine were randomly divided in four groups: GROUP C: 20 cows treated, within 24 h of calving, with 5 mL/head of saline solution; GROUP PG: 20 cows treated, within 24 h of calving, with 150 μg/head of d-cloprostenol; GROUP OX: 20 cows treated, within 24 h of calving, with 50 IU/head of oxytocin acetate; GROUP S: 20 cows treated, within 24 h of calving, with 40 mg/q Scopolamine Butylbromide. Each cow was subjected to blood samples to evaluate the Hydroxyproline (HYP) levels, at T0, within 24 h after calving, and T7, T14, T28, 7, 14, and 28 days after calving, respectively. At T14 and T28, an ultrasound examination was performed to measure the diameter of ex-pregnant horn. In all cows, the reproductive indices (days to first service and number of artificial insemination for conception) were evaluated. In all groups, the HYP concentrations have been rising from T0 to T28, with the maximum levels obtained at T28 in the groups PG and S. As regard the diameter of uterine horn, the comparison among the groups showed significant differences only at T28, with lower values in the group PG and S. In group S and PG, the days to first service were less than other groups. Treatment with Scopolamine and PGF2α resulted in better outcomes, evidenced clinically by more efficient uterine involution and faster ovarian recovery.

Effect of exogenous oestrogen treatment frequency on induction of artificial lactation in pseudopregnant sows.

In this study, we examined whether the frequency of exogenous oestrogen treatment affects the induction of artificial lactation and milk production. Furthermore, we analysed changes in milk components obtained from artificially lactating sows. Pseudopregnant induced by treatment with 30 mg of estradiol dipropionate (EDP) on Day 10 (Day 0 = the last day of estrus) were divided into three groups: those administered 5 mg of EDP once on Day 39 (n = 5), twice on Days 32 and 39 (n = 5) and three times on Days 25, 32 and 39 (n = 6). All animals were treated with prostaglandin F2α (PGF2α) on Day 46 for induced lactation. Artificial lactation was induced in 66.7%-80.0% of sows, and the EDP treatment frequency before PGF2α administration had no significant effect on either the induction rate of artificial lactation or the milk yield during the experimental period. The milk composition (levels of crude protein, crude fat, crude ash, lactose and immunoglobulin) did not differ among the groups. In conclusion, the number of EDP treatments prior to PGF2α administration had no effect on either the efficiency of artificial lactation induction or milk production.

Timed-artificial insemination protocols for Bos indicus beef heifers: Evaluation of protocol length and variations in prostaglandin F2α treatments

The aim was to compare reproductive outcomes of Nelore heifers submitted to timed AI (TAI) protocols, with 7 or 9 d of permanence of the intravaginal progesterone (P4) device and different times of prostaglandin F2α (PGF) administration, for first (n = 935) and second (n = 530) services. On Day −24, heifers without corpus luteum (CL) underwent a protocol for induction of ovulation. On Day 0, heifers received a P4 device (0.5 g) and 1.5 mg estradiol (E2) benzoate. In order for the TAI to be carried out on the same day, these treatments were performed 2 d later on the heifers treated with the 7-d protocol. Additionally, heifers received 0.5 mg PGF at different times, resulting in four experimental groups: 9dP4-PGFd9 (n = 365); 9dP4-PGFd7 (n = 369); 9dP4-PGFd0&9 (n = 364); 7dP4-PGFd0&7 (n = 367). These nomenclatures indicate for how many d the P4 device was kept and the specific day on which PGF was given. At P4 removal, all heifers received 0.5 mg E2 cypionate and 200 IU eCG, and TAI was performed 2 d later. Effects were considered significant when P ≤ 0.05 (superscript letters a,b) whereas a tendency was assumed when 0.05 < P ≤ 0.10. Groups 9dP4-PGFd0&9 and 7dP4-PGFd0&7 had lower percentage of heifers with CL at P4 removal. The diameter (mm) of the dominant follicle (DF) was affected by treatment at P4 removal (9dP4-PGFd9: 11.3 ± 0.3b; 9dP4-PGFd7: 11.8 ± 0.2ab; 9dP4-PGFd0&9: 12.6 ± 0.2a; 7dP4-PGFd0&7: 10.8 ± 0.2c) and at TAI (9dP4-PGFd9: 12.7 ± 0.3ab; 9dP4-PGFd7: 13.2 ± 0.2a; 9dP4-PGFd0&9: 13.4 ± 0.2a; 7dP4-PGFd0&7: 12.4 ± 0.3b). Expression of estrus (%) was affected by treatment (9dP4-PGFd9: 89.6a; 9dP4-PGFd7: 93.5a; 9dP4-PGFd0&9: 88.2ab; 7dP4-PGFd0&7: 85.6b). There were no differences among treatments for P/AI on Day 40 (30–35 d post AI), final P/AI (between Day 70 and parturition) and pregnancy loss (between Day 40 and final P/AI). When the permanence of the P4 device was compared, regardless of PGF treatments, 9-d protocols resulted in greater DF diameter at P4 removal and at TAI, and greater expression of estrus (90.4 vs. 85.6%) than the 7-d protocol. Despite that, the 7-d protocol resulted in greater P/AI on Day 40 (55.3 vs. 49.1%). In addition, there was an interaction between protocol duration and body weight, in which heavier heifers (≥ 307 kg) had greater P/AI when treated with the 7-d protocol, in comparison to 9-d. In conclusion, longer TAI protocols (9 d of P4 device duration) resulted in greater DF diameter and expression of estrus. However, the shorter TAI protocol (7 d of P4 device duration) produced greater P/AI on Day 40, particularly in heavier heifers. Within 9-d protocols, the additional dose of PGF on Day 0 or the anticipation of the PGF to Day 7 did not influence fertility.

Cloprostenol effect with and without male stimulation on oestrus synchronization in Peru guinea pigs.

Cloprostenol, a synthetic derivative of prostaglandin F2α, effectively triggers functional and morphological regression of the corpus luteum (luteolysis). In rural Peru, the guinea pig (Cavia porcellus) holds significance within the local economy and serves as a valuable protein source. Enhancing reproductive efficiency is crucial to achieve uniformity in weight, age, and litter size across commercial systems. Thus, our study aimed to evaluate the effect of cloprostenol with and without male stimulation on the onset, duration, and intensity of oestrus in Peru guinea pigs. A total of 128 guinea pigs (120 females and eight males) between 8 and 12 months of age, weighing between 800 and 1200 g, were distributed in cages of 15 females per treatment. Cloprostenol sodium (0 [control], 0.20, 0.25, and 0.30 mg/animal) was IM administered to the groups with and without male stimulation. Four isolated males in individual cages, different from the one used for the treatment, were considered to detect oestrus. The oestrus intensity was assessed by observing sexual behaviour signs such as restlessness, moaning, attempts to mount, pelvic elevation, loin stretching, and vulvar inflammation. The oestrus was manifested 2 days after the administration of cloprostenol sodium. At a dose of 0.30 mg/animal and with male stimulation, the earliest oestrus was observed at 46.9 h. There was a reduction in the oestrus duration (p < .05) in guinea pigs that received the three doses of cloprostenol sodium compared to the control group. The highest percentages of frank oestrus intensity (66.7%) were strongly associated with the administered doses of cloprostenol sodium (p < .01). In conclusion, the cloprostenol sodium administration was proper for rapid oestrus induction in Peru guinea pigs.

Integration of metabolomics and transcriptomics reveals the therapeutic mechanism underlying Chelidonium majus L. in the treatment of allergic asthma

BackgroundChelidonium majus is a well-known traditional Chinese medicine, and has been reported of the effect in relieving cough and asthma. However, the mechanism of action is still unknown.MethodsAsthmatic SD rats were first sensitized and established through ovalbumin (OVA) motivation. Subsequently, Hematoxylin and eosin (H&E) staining, Masson’s trichrome (Masson) staining, Periodic acid-Schiff (PAS) staining and inflammatory cytokines assay of interleukin (IL)-4, IL-6, IL-17 were implemented to evaluate the protective effects of Chelidonium majus on asthma. Then, the effects of Chelidonium majus and their molecular mechanisms of action on asthma were detected based on the integration of transcriptomics and metabolomics analyses.ResultsAfter administration with Chelidonium majus, the histological injuries of inflammation, collagen deposition and mucus secretion in lungs were attenuated and the serum inflammatory cytokines perturbations were also converted. Furthermore, integrated analysis revealed that after Chelidonium majus treatment, 7 different expression genes (DEGs) (Alox15, P4ha1, Pla2g16, Pde3a, Nme1, Entpd8 and Adcy9) and 9 metabolic biomarkers (ADP, Xanthosine, Hypoxanthine, Inosine, prostaglandin E2 (PGE2), prostaglandin F2a (PGF2a), phosphatidylserine, Creatine and LysoPC (10:0)) were discovered to be connected with the enrichment metabolic pathways, including Purine metabolism, Arachidonic acid metabolism, Arginine and proline metabolism and Glycerophospholipid metabolism. The obtained metabolic biomarkers and DEGs were mainly related to energy metabolism and inflammation, and may be potential therapeutic targets.ConclusionChelidonium majus relieved OVA-induced asthma in rats by regulating the Alox15, P4ha1, Pla2g16, Pde3a, Nme1, Entpd8 and Adcy9 genes expression to restore the disorders in energy metabolism and inflammation.

Mechanisms of electroacupuncture relieves uterine smooth muscle spasm in dysmenorrhea rats based on Rho/ROCK signaling pathway.

To investigate the effect of electroacupuncture (EA) on Rho/Rho-associated coiled-coil-forming kinases (ROCK) signaling pathway of uterus tissue in rats with dysmenorrhea, so as to explore the underlying mechanism of EA treating primary dysmenorrhea (PD) and uterine smooth muscle spasm, and to observe whether there is a difference in the effect of meridian acupoints in Conception Vessel (CV) and Governer Vessel (GV). Sixty female SD rats were randomly divided into saline, model, CV, GV, and non-acupoint groups, with 12 rats in each group. The dysmenorrhea model was established by subcutaneous injection of estradiol diphenhydrate combined with intraperitoneal injection of oxytocin (OT). EA (2 Hz) was applied to "Qihai" (CV6) and "Zhongji" (CV3) for CV group, "Mingmen" (GV4) and "Yaoshu" (GV2) for GV group, "non-acupoint 1" and "non-acupoint 3" on the left side for non-acupoint group, and manual acupuncture was applied to "Guanyuan" (CV4) for CV group, "Yaoyangguan" (GV3) for GV group, "non-acupoint 2" on the left side for non-acupoint group. The treatment was conducted for 20 min each time, once daily for 10 days. The writhing score was evaluated. The smooth myoelectric signals of rats' uterus in vivo were recorded by multi-channel physiological recorder. The uterine histopathological changes were observed by HE staining. The contents of prostaglandin F2α (PGF2α), OT and calcium ion (Ca2+) in uterine tissue of rats were detected by ELISA. The protein and mRNA expression levels of smooth muscle 22-α (SM22-α), RhoA and ROCKⅡ in uterine tissue were detected by Western blot and fluorescence quantitative PCR, respectively. Compared with the saline group, the writhing score of rats in the model group was increased (P<0.01), the amplitude voltage of uterine smooth muscle in vivo was elevated (P<0.01), the contents of PGF2α, OT and Ca2+, the protein and mRNA expression of SM22-α, RhoA and ROCK Ⅱ in uterine tissue were all increased (P<0.01). Compared with the model and the non-acupoint groups, the writhing scores of the CV and the GV groups were decreased (P<0.01, P<0.05), the amplitude voltage of uterine smooth muscle was decreased (P<0.01), the contents of PGF2α, OT and Ca2+ in uterine tissue were decreased (P<0.01, P<0.05), and the protein expression and mRNA expression of SM22-α, RhoA and ROCKⅡ in uterine tissue were decreased (P<0.01, P<0.05). HE staining showed extensive exfoliation of uterine intima with severe edema and increased glandular secretion in the model group, which was alleviated in the CV and GV groups. EA at acupoints of CV and GV can significantly reduce the writhing score, uterine smooth muscle amplitude voltage, pathological injury degree of uterus, and relieve spasm of uterine smooth muscle in dysmenorrhea rats, which may be related to its effect in regulating PGF2α and OT contents, inhibiting the Rho/ROCK signaling pathway, and reducing the SM22-α, RhoA, ROCKⅡ protein and mRNA expression, and Ca2+ content in uterine tissue.

De novo reconstruction of a functional in vivo-like equine endometrium using collagen-based tissue engineering.

To better understand molecular aspects of equine endometrial function, there is a need for advanced in vitro culture systems that more closely imitate the intricate 3-dimensional (3D) in vivo endometrial structure than current techniques. However, development of a 3D in vitro model of this complex tissue is challenging. This study aimed to develop an in vitro 3D endometrial tissue (3D-ET) with an epithelial cell phenotype optimized by treatment with a Rho-associated protein kinase (ROCK) inhibitor. Equine endometrial epithelial (eECs) and mesenchymal stromal (eMSCs) cells were isolated separately, and eECs cultured in various concentrations of Rock inhibitor (0, 5, 10µmol) in epithelial medium (EC-medium) containing 10% knock-out serum replacement (KSR). The optimal concentration of Rock inhibitor for enhancing eEC proliferation and viability was 10µM. However, 10µM Rock inhibitor in the 10% KSR EC-medium was able to maintain mucin1 (Muc1) gene expression for only a short period. In contrast, fetal bovine serum (FBS) was able to maintain Muc1 gene expression for longer culture durations. An in vitro 3D-ET was successfully constructed using a collagen-based scaffold to support the eECs and eMSCs. The 3D-ET closely mimicked in vivo endometrium by displaying gland-like eEC-derived structures positive for the endometrial gland marker, Fork headbox A2 (FOXA2), and by mimicking the 3D morphology of the stromal compartment. In addition, the 3D-ET expressed the secretory protein MUC1 on its glandular epithelial surface and responded to LPS challenge by upregulating the expression of the interleukin-6 (IL6) and prostaglandin F synthase (PGFS) genes (P < 0.01), along with an increase in their secretory products, IL-6 (P < 0.01) and prostaglandin F2alpha (PGF2α) (P < 0.001) respectively. In the future, this culture system can be used to study both normal physiology and pathological processes of the equine endometrium.

Female Type 1 Diabetic Akita Mice Demonstrate Increased Bladder Contractility via FP Receptor Activation due to NLRP3-Mediated Inflammation.

Diabetic bladder dysfunction (DBD) is driven in part by inflammation which dysregulates prostaglandin release in the bladder. Precise inflammatory mechanisms responsible for such dysregulation have been elusive. Since prostaglandins impact bladder contractility, elucidating these mechanisms may yield potential therapeutic targets for DBD. In female Type 1 diabetic Akita mice, inflammation mediated by the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome is responsible for DBD. Here, we utilized female Akita mice crossbred with NLRP3 knock-out mice to determine how NLRP3-driven inflammation impacts prostaglandin release within the bladder and prostaglandin-mediated bladder contractions. Akita mice were crossbred with NLRP3-⁣/- mice to yield four groups of non-diabetics and diabetics with and without the NLRP3 gene. Females were aged to 30 weeks when Akitas typically exhibit DBD. Urothelia and detrusors were stretched ex vivo to release prostaglandins. Prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α) were quantified using enzyme linked immunosorbent assays (ELISA). In separate samples, ex vivo contractile force to PGE2 and PGF2α +/- the prostaglandin F (FP) receptor antagonist, AL8810, was measured. FP receptor protein expression was determined via western blotting. Stretch-induced PGE2 release increases in urothelia but decreases in detrusors of diabetics. However, PGE2-mediated bladder contractions are not impacted. Conversely, diabetics show no changes in PGF2α release, but PGF2α-mediated contractions increase significantly. This is likely due to signaling through the FP receptors as FP receptor antagonism prevents this increase and diabetics demonstrate a four-fold increase in FP receptor proteins. Without NLRP3-mediated inflammation, changes in prostaglandin release, contractility, and receptor expression do not occur. NLRP3-dependent inflammation dysregulates prostaglandin release and prostaglandin-mediated bladder contractions in diabetic female Akita mice via FP receptor upregulation.

The Essential Role of PGF2α/PTGFR in Molding Endometrial Breakdown and Vascular Dynamics, Regulated by HIF-1α in a Mouse Menstrual-like Model.

In women of childbearing age, extensive decidualization, shedding and remodeling of the endometrium during the menstrual cycle are fundamental for successful pregnancy. The role of prostaglandins (PGs) in menstruation has long been proposed in humans, and the rate-limiting enzyme cyclooxygenase was shown to play a key role in endometrial breakdown and shedding in a mouse menstrual-like model in our previous study. However, the specific types of PGs involved and their respective roles remain unclear. Therefore, our objective was to investigate the mechanism through which PGs regulate endometrial disintegration. In this study, the microscopy was observed by HE; the protein levels of prostaglandins E1 (PGE1), prostaglandins E2 (PGE2), prostaglandin F2α (PGF2α) and Prostaglandin I2 (PGI2) were detected by ELISA; the mRNA level of Pfgfr2, Vascular Endothelial Growth Factor(Vegf), Angiostatin and Hypoxia inducible factor-1α (Hif1α) were examined by real-time PCR; PTGFR Receptor (PTGFR), VEGF, Angiostatin and HIF-1α protein levels were investigated by western blotting; the locations of protein were observed by Immunohistochemistry; HIF-1α binding PTGFR promoter was detected by Chromatin Immunoprecipitation (ChIP) and real-time PCR. We found that the concentrations of PGE1, PGE2, and PGF2α all increased significantly during this process. Furthermore, Ptgfr mRNA increased soon after Progesterone (P4) withdrawal, and PTGFR protein levels increased significantly during abundant endometrial breakdown and shedding processes. PTGFR inhibitors AL8810 significantly suppressed endometrial breakdown and shedding, promoted Angiostatin expression, and reduced VEGF-A expressions and vascular permeability. And HIF-1α and PTGFR were mainly located in the luminal/gland epithelium, vascular endothelium, and pre-decidual zone. Interestingly, HIF-1α directly bound to Ptgfr promoter. Moreover, a HIF-1α inhibitor 2-methoxyestradiol (2ME) significantly reduced PTGFR expression and suppressed endometrial breakdown which was in accord with PTGFR inhibitor's effect. Similar changes occurred in human stromal cells relevant to menstruation in vitro. Our study provides evidence that PGF2α/PTGFR plays a vital role in endometrial breakdown via vascular changes that are regulated by HIF-1α during menstruation.

Evaluating estrus synchronization and early pregnancy detection in Ossimi sheep: The influence of fluorogestone acetate treatment duration and dosage

Estrus synchronization is important for improving sheep reproduction. To enhance sheep reproduction efficiency, this study investigated the impact of different durations (7 vs. 14 days) and fluorogestone acetate (FGA) doses in intravaginal sponges on estrus synchronization and early pregnancy detection in Ossimi sheep. Two hundred ewes were evenly divided into two groups, each receiving a full 40 mg or a halved 20 mg FGA sponge for their respective durations. The study aimed to optimize breeding efficiency by examining the effectiveness of these treatments in synchronizing estrous cycles and by evaluating the use of serum levels of pregnancy-associated glycoprotein 1 (PAG1) and progesterone (P4) as markers for early pregnancy identification. Prostaglandin F2α and equine chorionic gonadotropin were administered to enhance the synchronization process. Results highlighted that the 7-day treatment protocol significantly improved estrus, pregnancy, and lambing rates compared to the 14-day protocol. Furthermore, pregnant ewes demonstrated elevated levels of PAG1 and P4, with PAG1 levels particularly higher in ewes with multiple pregnancies. The findings underscore that the shorter duration of FGA treatment is more effective for reproductive management in Ossimi sheep without significantly affecting PAG1 levels based on the dose or duration of FGA. PAG1 also proved to be a reliable marker for early pregnancy detection, offering a promising approach to identifying fetal numbers early in pregnancy. This research suggests optimizing FGA sponge use could be cost-efficient for improving reproductive efficiency and early pregnancy management in sheep.