Mice deficient in the phosphatase activity of sEH show decreased levels of the endocannabinoid 2-AG in the olfactory bulb and depressive-like behavior.

Soluble epoxide hydrolase (sEH) is a bifunctional enzyme that has epoxide hydrolase activity and phosphatase activity. Our earlier study revealed that lysophosphatidic acids are a substrate of the phosphatase activity of sEH in vitro, but its physiological function remained unknown. Herein, we used the CRISPR/Cas9 system and i-GONAD method to generate mice that are deficient in sEH phosphatase activity. In the mouse brain, sEH was highly expressed in the olfactory bulb. Deletion of the sEH phosphatase activity resulted in decreased levels of the endocannabinoid 2-arachidonoyl glycerol (2-AG), which is a dephosphorylated form of 2-arachidonoyl-lysophosphatidic acid in the olfactory bulb. The sEH-deficient mice showed depressive-like behavior. These results indicate that sEH can regulate the production of 2-AG and brain function in vivo.

Constitutive activation of estrogen receptor α signaling in muscle prolongs exercise endurance in mice.

Estrogen is a female hormone that plays a role in various tissues, although the mechanism in skeletal muscle has not been fully clarified. We previously showed that systemic administration of estrogen for 10 weeks ameliorated decreased exercise endurance in ovariectomized mice. To assess whether a long-term and muscle-specific activation of estrogen signaling modulates muscle function, we constructed an expression plasmid for a constitutively active estrogen receptor α (caERα) under the control of muscle creatine kinase (Mck) gene promoter/enhancer. In C2C12 mouse myoblastic cells, transfection of the Mck-caERα plasmid elevated the estrogen response element-driven transcription in a ligand-independent manner. Using this construct, we generated Mck-caERα transgenic mice, in which caERα is predominantly expressed in muscle. Treadmill running test revealed that female Mck-caERα mice exhibit a prolonged running time and distance compared with the wild-type mice. Moreover, microarray expression analysis revealed that the genes related to lipid metabolism, insulin signaling, and growth factor signaling were particularly upregulated in the quadriceps femoris muscle of Mck-caERα mice. These results suggest that estrogen signaling potentiates exercise endurance in skeletal muscle through modulating the expression of metabolism-associated genes.

Nitric oxide-soluble guanylyl cyclase pathway as a contributor to age-related memory impairment in Drosophila.

Age-related changes in the transcriptome lead to memory impairment. Several genes have been identified to cause age-dependent memory impairment (AMI) by changes in their expression, but genetic screens to identify genes critical for AMI have not been performed. The fruit fly is a useful model for studying AMI due to its short lifespan and the availability of consistent techniques and environments to assess its memory ability. We generated a list of candidate genes that act as AMI regulators by performing a comprehensive analysis of RNAsequencing data from young and aged fly heads and genome-wide RNAi screening data to identify memory-regulating genes. A candidate screen using temporal and panneuronal RNAi expression was performed to identify genes critical for AMI. We identified the guanylyl cyclase ß-subunit at 100B (gycß) gene, which encodes a subunit of soluble guanylyl cyclase (sGC), the only intracellular nitric oxide (NO) receptor in fruit flies, as a negative regulator of AMI. RNAi knockdown of gycß in neurons and NO synthase (NOS) in glia or neurons enhanced the performance of intermediate-term memory (ITM) without apparent effects on memory acquisition. We also showed that pharmacological inhibition of sGC and NOS enhanced ITM in aged individuals, suggesting the possibility that age-related enhancement of the NO-sGC pathway causes memory impairment.

Postsurgical Intrauterine Adhesions after Hysteroscopic Myomectomy Using the Myoma Pseudocapsule Preservation Technique Evaluated bv Second-look Hysteroscopy: A Retrospective Comparative Study.

STUDY OBJECTIVE: To analyze the frequency and risk factors of postsurgical intrauterine adhesions (IUAs) using second-look hysteroscopy (SLH) in patients undergoing hysteroscopic myomectomy performed using the myoma pseudocapsule preservation technique for submucosal myoma. DESIGN: Retrospective cohort study. SETTING: University hospital from January 2017 to December 2019. PATIENTS: A total of 124 patients underwent hysteroscopic myomectomy and SLH. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Surgical duration, intraoperative blood loss, number of enucleated myomas, volume of specimen, and postsurgical IUA evaluated by SLH. Postsurgical IUA were found in 5 of 124 cases (4.0%) at SLH. There were no cases of IUA formation in cases in which a single myomas was resected (0 of 83 cases, 0%); all cases were multiple myomas (5 of 41 cases, 12.2%), and IUA significantly occurred more frequently in cases of multiple myoma (p = .003). Univariate analyses showed that the IUA group contained a significantly larger number of enucleated uterine myoma (p <.001), required a longer operation (p = .003), and displayed an increased volume of intraoperative bleeding (p = .007), and the heavier the specimen, the greater the number of patients that had inserted an intrauterine device than the group that did not display postsurgical IUA. Multivariate logistic regression analysis of the risk factors of postsurgical IUA showed that the number of enucleated myomas was strongly associated with IUA (odds ratio, 1.45; 95% confidence interval, 1.06-1.97). CONCLUSION: The frequency of postsurgical IUA after hysteroscopic myomectomy was high in cases of multiple myoma and may be a risk factor. SLH should be actively pursued in cases where the patient desires to bear children, and an informed consent should be attained before performing surgery.

Incidences and risk factors of moderate-to-severe ovarian hyperstimulation syndrome and severe hemoperitoneum in 1,435,108 oocyte retrievals.

RESEARCH QUESTION: What are the risk factors affecting the incidences of moderate-to-severe ovarian hyperstimulation syndrome (OHSS) and severe hemoperitoneum in assisted reproductive technology (ART) treatment cycles? DESIGN: A retrospective cohort study was conducted on 1,435,108 oocyte retrieval cycles among Japanese ART registry data between 2007 and 2015. The study included 11,378 cycles with moderate-to-severe OHSS, 1182 cycles with severe hemoperitoneum, including 27 cycles with both conditions, and 1,422,575 cycles without moderate-to-severe OHSS and severe hemoperitoneum. RESULTS: The incidences of moderate-to-severe OHSS and severe hemoperitoneum were 0.79% and 0.08%, respectively, and decreased by 0.57-fold and 0.29-fold from 2007 to 2015, respectively. In cycles with OHSS and cycles with hemoperitoneum women were younger (odds ratios [OR] 0.91 and 0.95, respectively) and had more retrieved oocytes (OR 1.09 and 1.01, respectively) compared with cycles without both complications. The use of a gonadotrophin-releasing hormone (GnRH) agonist protocol for ovarian stimulation was the highest risk factor in cycles with OHSS and hemoperitoneum (OR 1.83 and 1.24, respectively), followed by GnRH antagonist protocol (reference), gonadotrophin with or without oral medicine (OR 0.45 and 0.56, respectively) and natural or oral medicine (OR 0.02 and 0.19, respectively). In fresh embryo transfer, clinical pregnancy was associated with an increased risk of OHSS and hemoperitoneum (OR 1.19 and 2.34, respectively). CONCLUSIONS: The highest risk factors affecting OHSS and hemoperitoneum were the use of a GnRH agonist protocol and clinical pregnancy following fresh embryo transfer. The incidences of OHSS and hemoperitoneum have decreased yearly with a reduction of GnRH agonist use and fresh embryo transfer.

Sex differences in factors associated with poor subjective sleep quality in athletes.

BACKGROUND: Sleep is an important recovery period for athletes. In general, women are not satisfied with their sleep quality, which is also true for female soccer players, although the reasons remain to be elucidated. This study aimed to confirm sex difference in sleep quality among athletes from various fields of sport, and to investigate factors related to poor subjective sleep quality in male and female athletes. METHODS: We collected data concerning subjective sleep quality, measured by Pittsburgh Sleep Quality Index (PSQI), from athletes who were 16 to 40 years of age and played various types of sports. Data concerning their sports, lifestyle, and sleep issues and sleep environments, and also menstrual issues for females, were collected. RESULTS: Data from 207 male athletes and 215 female athletes were assessed. Among them, 31.4% of men and 48.8% of women had poor subjective sleep quality (i.e., PSQI≥6). In male athletes, witnessed apnea, episodes of disorientation or confusion during the time of sleep, long time gap between dinner and bedtime, and turning on the heating in the winter, were identified as factors associated with poor sleep quality by multivariate analysis, whereas in female athletes, bathing close to bedtime, habitual drinking, and being annoyed by noises at bedtime were identified. CONCLUSIONS: In both populations, females had poorer subjective sleep quality than males. Sex differences exist in factors associated with poor subjective sleep quality. Thus, different approaches should be considered to improve their sleep quality.

Evidence for detection of rat P2X4 receptor expressed on cells by generating monoclonal antibodies recognizing the native structure.

P2X purinergic receptors are ATP-driven ionic channels expressed as trimers and showing various functions. A subtype, the P2X4 receptor present on microglial cells is highly involved in neuropathic pain. In this study, in order to prepare antibodies recognizing the native structure of rat P2X4 (rP2X4) receptor, we immunized mice with rP2X4's head domain (rHD, Gln111-Val167), which possesses an intact structure stabilized by S-S bond formation (Igawa and Abe et al. FEBS Lett. 2015), as an antigen. We generated five monoclonal antibodies with the ability to recognize the native structure of its head domain, stabilized by S-S bond formation. Site-directed mutagenesis revealed that Asn127 and Asp131 of the rHD, in which combination of these amino acid residues is only conserved in P2X4 receptor among P2X family, were closely involved in the interaction between rHD and these antibodies. We also demonstrated the antibodies obtained here could detect rP2X4 receptor expressed in 1321N1 human astrocytoma cells.

Estrogen signaling increases nuclear receptor subfamily 4 group A member 1 expression and energy production in skeletal muscle cells.

Estrogen deficiency has been known to associate with musculoskeletal diseases in women, based on the clinical observations of frequent susceptibility to osteoporosis and sarcopenia among postmenopausal women. In skeletal muscles, estrogen has been assumed to play physiological roles in maintaining muscle mass and strength, although its precise molecular mechanism remains to be elucidated. We have previously shown that estrogen regulates energy metabolism through the downregulation of mitochondrial uncoupling protein 3 (UCP3) in skeletal muscles, which may contribute to the prolonged exercise endurance in female mice. In the present study, we investigated the effects of estrogen on the expression levels of all members of the nuclear receptor superfamily. Microarray analysis showed that the mRNA level of nuclear receptor subfamily 4 group A member 1 (Nr4a1) was upregulated by the transduction of a recombinant adenovirus expressing constitutively active estrogen receptor α (caERα) in differentiated myoblastic C2C12 cells. Thus we assumed that NR4A1 may be an estrogen-inducible gene in myoblastic cells. We also demonstrated that caERα increases the cellular ATP content along with an increase in mitochondrial DNA content in differentiated myoblastic C2C12 cells. In contrast, the knockdown of Nr4a1 using siRNA exhibited reduced ATP generation as well as a decrease in mitochondrial DNA content. Overall, the present study indicates a crosstalk between estrogen signaling and NR4A1 in skeletal muscle cells. We consider that estrogen-dependent NR4A1 upregulation could increase efficient ATP generation in skeletal muscle cells partly through enhancing mitochondrial functions.

Estrogen modulates exercise endurance along with mitochondrial uncoupling protein 3 downregulation in skeletal muscle of female mice.

Estrogen is a hormone that regulates physiological processes and its dysregulation may relate to muscle disorders particularly in female, although the mechanism remains to be elucidated. We here show that estrogen deficiency repressed exercise endurance in female mice whereas the administration of estrogen to ovariectomized mice recovered it. Microarray analysis of mouse muscles showed that mitochondrial uncoupling protein 3 (UCP3) is upregulated by ovariectomy and downregulated by estrogen administration. Intriguingly, ectopic expression of constitutively active estrogen receptor α decreased UCP3 level and increased cellular ATP content in differentiated myoblastic C2C12 cells. Overall, the present study suggests that estrogen plays a critical role in the regulation of energy expenditure and exercise endurance in female.

Elevated serum thyroid-stimulating hormone is associated with decreased anti-Müllerian hormone in infertile women of reproductive age.

PURPOSE: Thyroid dysfunction and autoimmune thyroiditis are associated with fertility in women of reproductive age. Anti-Müllerian hormone (AMH), a known biomarker of ovarian function, may be affected by impaired thyroid function; however, the relationship between AMH and thyroid hormone has not been elucidated. METHODS: In this case-control study, to identify the impact of thyroid hormone on ovarian reserve, we recruited 67 consecutive Japanese infertile patients and 27 normal fertile women aged 30-39 years without impact factors on thyroid and ovarian functions between 2012 and 2013. We assessed patient age, BMI and AMH, prolactin, TSH and FT4 levels of all study participations as independent variables. To evaluate the relationship between AMH and thyroid hormone, we matched patients by age and body mass index as confounding factors using 1:1 matching for statistical analysis of healthy fertile women and infertile patients and obtained 23 pairs. Then, independent variables were subjected to multiple regression analysis. RESULTS: Multiple regression analysis showed that both thyroid-stimulating hormone (TSH) levels and patient age were negatively correlated with AMH levels in infertile patients (patient age and TSH: standardized partial regression coefficient (ß), -0.534 and -0.361; p = 0.003 and 0.036, respectively), but not in normal fertile women. CONCLUSIONS: AMH levels were inversely correlated with TSH levels in infertile women of reproductive age.