Discovery of a mu-opioid receptor modulator that in combination with morphinan antagonists induces analgesia.

Morphinan antagonists, which block opioid effects at mu-opioid receptors, have been studied for their analgesic potential. Previous studies have suggested that these antagonists elicit analgesia with fewer adverse effects in the presence of the mutant mu-opioid receptor (MOR; S196A). However, introducing a mutant receptor for medical applications represents significant challenges. We hypothesize that binding a chemical compound to the MOR may elicit a comparable effect to the S196A mutation. Through high-throughput screening and structure-activity relationship studies, we identified a modulator, 4-(2-(4-fluorophenyl)-4-oxothiazolidin-3-yl)-3-methylbenzoic acid (BPRMU191), which confers agonistic properties to small-molecule morphinan antagonists, which induce G protein-dependent MOR activation. Co-application of BPRMU191 and morphinan antagonists resulted in MOR-dependent analgesia with diminished side effects, including gastrointestinal dysfunction, antinociceptive tolerance, and physical and psychological dependence. Combining BPRMU191 and morphinan antagonists could serve as a potential therapeutic strategy for severe pain with reduced adverse effects and provide an avenue for studying G protein-coupled receptor modulation.

A Preliminary Investigation of the Roles of Endometrial Cells in Endometriosis Development via In Vitro and In Vivo Analyses.

Endometriosis is a complex gynecological disease that affects more than 10% of women in their reproductive years. While surgery can provide temporary relief from women's pain, symptoms often return in as many as 75% of cases within two years. Previous literature has contributed to theories about the development of endometriosis; however, the exact pathogenesis and etiology remain elusive. We conducted a preliminary investigation into the influence of primary endometrial cells (ECs) on the development and progression of endometriosis. In vitro studies, they were involved in inducing Lipopolysaccharide (LPS) in rat-isolated primary endometrial cells, which resulted in increased nuclear factor-kappa B (NF-κB) and vascular endothelial growth factor (VEGF) mRNA gene expression (quantitative polymerase chain reaction analysis, qPCR) and protein expression (western blot analysis). Additionally, in vivo studies utilized autogenic and allogeneic transplantations (rat to rat) to investigate endometriosis-like lesion cyst size, body weight, protein levels (immunohistochemistry), and mRNA gene expression. These studies demonstrated that estrogen upregulates the gene and protein regulation of cytoskeletal (CK)-18, transforming growth factor-ß (TGF-ß), VEGF, and tumor necrosis factor (TNF)-α, particularly in the peritoneum. These findings may influence cell proliferation, angiogenesis, fibrosis, and inflammation markers. Consequently, this could exacerbate the occurrence and progression of endometriosis.

A dual nociceptin and mu opioid receptor agonist exhibited robust antinociceptive effect with decreased side effects.

The compelling demand of a consummate analgesic medication without addiction is rising due to the clinical mistreatment. Additionally, the series of severe untoward effects usually deterred the utilization while coping with serious pain. As a possible turning point, we revealed that compound 14 is a dual agonist of mu opioid receptor (MOR) and nociceptin-orphanin FQ opioid peptide (NOP) receptor in this study. More importantly, compound 14 achieves pain relieving at very small doses, meanwhile, reduces several unwanted side effects such as constipation, reward, tolerance and withdrawal effects. Here, we evaluated the antinociception and side effects of this novel compound from wild type and humanized mice to further develop a safer prescription analgesic drug.

Y-chromosome genes associated with sertoli cell-only syndrome identified by array comparative genome hybridization.

BACKGROUND: The precise contribution of each chromosome gene or gene family in achieving male fertility is still the subject of debate. Most studies have examined male populations with heterogeneous causes of infertility, and have therefore reached controversial or uncertain conclusions. This study uses Y-chromosome array-based comparative genomic hybridization (aCGH) to examine a population of males with a uniform sertoli cell-only syndrome (SCOS) infertility phenotype. METHODS: Initial analysis of gene copy number variations in 8 SCOS patients, with determination of the log-ratio of probe signal intensity against a DNA reference, was performed using the Y-chromosome NimbleGen aCGH. To confirm the role of candidate genes, real-time quantitative RT-PCR was used to compare 19 patients who had SCOS non-obstructive azoospermia with 15 patients who had obstructive azoospermia but normal spermatogenesis. RESULTS: Our initial aCGH experiments identified CDY1a and CDY1b double deletions in all 8 patients who had total germ cell depletion. However, 5 patients had DAZ1/2 and DAZ3/4 deletions, 1 patient had a DAZ2 and DAZ3/4 deletion, and 2 patients had no DAZ1/2 or DAZ3/4 deletions. Examination of testicular mRNA expression in another 19 patients with SCOS indicated all patients had no detectable levels of CDY1. CONCLUSIONS: Our findings indicate that CDY1 deletion in SCOS patients, and analysis of the expression of DAZ and CDY1 genes using aCGH and quantitative RT-PCR, may be useful to predict the presence of mature spermatozoa.

Benzo[b]thiophene-2-carboxamides as novel opioid receptor agonists with potent analgesic effect and reduced constipation.

Currently, there is a significant unmet need for novel analgesics with fewer side effects. In this study, we carried out structural modification of a hit compound previously identified in an artificial-intelligence (AI) virtual screening and discovered the potent analgesic, benzo[b]thiophene-2-carboxamide analog (compound 25) with new structural scaffold. We investigated the signaling pathways of opioid receptors mediated by compound 25, and found this racemic compound activated mu-opioid receptor through the cyclic adenosine monophosphate (cAMP) and ß-arrestin-2-mediated pathways with strong potency and efficacy, and accompanying nociceptin-orphanin FQ opioid peptide and delta-opioid receptors through the cAMP pathway with weak potencies. Compound 25 elicited potent antinociception in thermal-stimulated pain (ED50 value of 127.1 ± 34.65 µg/kg) and inflammatory-induced allodynia models with less gastrointestinal transit inhibition and antinociceptive tolerance than morphine. Overall, this study revealed a novel analgesic with reduced risks of side effects.

Selective and antagonist-dependent µ-opioid receptor activation by the combination of 2-{[2-(6-chloro-3,4-dihydro-1(2H)-quinolinyl)-2-oxoethyl]sulfanyl}-5-phenyl-4,6-(1H,5H)-pyrimidinedione and naloxone/naltrexone.

We identified, via high-throughput screening using a FLIPR® calcium assay, compound 1, which incorporated a dihydroquinolinyl-2-oxoethylsulfanyl-(1H,5H)-pyrimidinedione core and activated the µ-opioid receptor (MOR) in the presence of naloxone or naltrexone. A structure-activity relationship study of the analogs of 1 led to the design of compound 21, which activated MOR in the presence of naloxone with an EC50 of 3.3 ± 0.2 µM. MOR activation by the compound 21-antagonist pair was antagonist-dependent. Compound 21 did not affect the potency of the orthosteric agonist, morphine, toward MOR, indicating that it affected the function of MOR antagonists rather than that of the agonists. Computer modeling of the compound 21-MOR-naloxone complex revealed major interactions between compound 21 and MOR, including hydrogen bonding with Ser196, π-π stacking with Tyr149, and sulfur-aromatic interaction with Trp192. This study may pave the way for developing agents capable of safe and effective MOR modulation.

Morphine produces potent antinociception, sedation, and hypothermia in humanized mice expressing human mu-opioid receptor splice variants.

Morphine is a strong painkiller acting through mu-opioid receptor (MOR). Full-length 7-transmembrane (TM) variants of MOR share similar amino acid sequences of TM domains in rodents and humans; however, interspecies differences in N- and C-terminal amino acid sequences of MOR splice variants dramatically affect the downstream signaling. Thus, it is essential to develop a mouse model that expresses human MOR splice variants for opioid pharmacological studies. We generated 2 lines of fully humanized MOR mice (hMOR; mMOR mice), line #1 and #2. The novel murine model having human OPRM1 genes and human-specific variants was examined by reverse-transcription polymerase chain reaction and the MinION nanopore sequencing. The differences in the regional distribution of MOR between wild-type and humanized MOR mice brains were detected by RNAscope and radioligand binding assay. hMOR; mMOR mice were characterized in vivo using a tail-flick, charcoal meal, open field, tail suspension, naloxone precipitation tests, and rectal temperature measurement. The data indicated that wild-type and humanized MOR mice exhibited different pharmacology of morphine, including antinociception, tolerance, sedation, and withdrawal syndromes, suggesting the presence of species difference between mouse and human MORs. Therefore, hMOR; mMOR mice could serve as a novel mouse model for pharmacogenetic studies of opioids.

Growth hormone supplementation may improve the pregnancy rate and endometrial receptivity among women aged more than 40 years undergoing in vitro fertilization.

BACKGROUND: Growth hormone (GH) supplements have been shown to improve pregnancy and live-birth rates, suggesting that GH has a beneficial effect on oocyte quality. However, the effects of GH on implantation and receptivity remain unknown. This study evaluated the efficacy of GH in women aged more than 40 years participating in assisted reproductive technology (ART) programs. METHODS: Cycles of in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) in women aged more than 40 years (range, 40-43 years) between January 2009 and March 2014 at a university-based reproductive center were reviewed. Women were divided into two groups, those with and without GH co-stimulation. ART outcomes were evaluated. RESULTS: Supplement of GH significantly lowered cycle cancellation rate by increasing the per cycle rates of harvesting at least one oocyte and transferring at least one embryo (80.2% vs. 69.4%). GH increased the per cycle clinical pregnancy (15.9% vs. 6.8%) and favorable ultrasonic endometrial pattern (60.9% vs. 39.3%) rates. GH also increased the per transfer clinical pregnancy (19.9% vs. 9.9%) and implantation (11.2% vs. 5.2%) rates and the rate of a favorable ultrasonic endometrial pattern (65.1% vs. 45.0%). CONCLUSION: GH supplementation reduces the cycle cancellation rate in women aged more than 40 years, and increases the favorable ultrasonic endometrial pattern, pregnancy, and implantation rates by its beneficial actions on embryo quality and endometrial receptivity.

Limited relationships between reactive oxygen species levels in culture media and zygote and embryo development.

PURPOSE: Reactive oxygen species (ROS) are thought to play a critical role in the success of IVF. The relationships between oxidative stress parameters in culture media and IVF outcomes have not been extensively investigated. The objective of this study is to examine the relationships between early human embryonic parameters and levels of ROS in culture media. METHODS: This prospective study was conducted with 2633 spent culture media collected from patients undergoing conventional IVF (n = 101) and intracytoplasmic sperm injection (ICSI) (n = 60). Both fertilization and early culture were performed in universal IVF medium and G series medium. ROS levels were measured by chemiluminescence assays using luminol as the probe on days 1, 3, and 5 and determined the relationships of ROS levels with zygote condition, embryo quality, and clinical pregnancy rate. RESULTS: ROS levels per embryo in culture media on the corresponding days 1, 3, and 5 showed significant correlations between each pair in the total cohort. Similar results were observed in the IVF and ICSI groups, but day 1 and day 3 ROS levels were significantly higher in culture media of IVF than of ICSI embryos. ROS levels in culture medium were not significantly associated with embryo quality, blastocyst formation, or arrest. ROS levels on day 1 were similar in media of normally fertilized zygotes, unfertilized oocytes, and polyspermic zygotes and were not associated with delayed embryonic development, high fragmentation, blastocyst formation, or arrest after prolonged culture. ROS levels in media were not associated with the likelihood of conception. CONCLUSIONS: ROS levels in culture media may not be an effective indicator of embryo selection for IVF.

Up-regulation of SOX9 in sertoli cells from testiculopathic patients accounts for increasing anti-mullerian hormone expression via impaired androgen receptor signaling.

BACKGROUND: Testosterone provokes Sertoli cell maturation and represses AMH production. In adult patients with Sertoli-cells-only syndrome (SCOS) and androgen insensitivity syndrome (AIS), high level of AMH expression is detected in Sertoli cells due to defect of androgen/AR signaling. OBJECTIVE: We postulated that up-regulation of SOX9 due to impairment of androgen/AR signaling in Sertoli cells might explain why high level of anti-Mullerian hormone (AMH) expression occur in these testiculopathic patients. METHODS: Biological research of testicular specimens from men with azoospermia or mouse. The serum hormone levels were studied in 23 men with obstructive azoospermia, 33 men with SCOS azoospermia and 21 volunteers with normal seminograms during a period of 4 years. Immunohistochemical staining and reverse-transcription PCR were used to examine the relationships among AR, SOX9 and AMH expression in adult human and mouse testes. The ability of AR to repress the expression of SOX9 and AMH was evaluated in vitro in TM4 Sertoli cells and C3H10T1/2 cells. RESULTS: SCOS specimens showed up-regulation of SOX9 and AMH proteins but down-regulation of AR proteins in Sertoli cells. The mRNA levels of AR were significantly lower and the SOX9, AMH mRNA levels higher in all SCOS patients compared to controls (P< 0.05). The testosterone levels in the SCOS patients were within the normal range, but most were below the median of the controls. Furthermore, our in vitro cell line experiments demonstrated that androgen/AR signaling suppressed the gene and protein levels of AMH via repression of SOX9. CONCLUSIONS: Our data show that the functional androgen/AR signaling to repress SOX9 and AMH expression is essential for Sertoli cell maturation. Impairment of androgen/AR signaling promotes SOX9-mediated AMH production, accounts for impairments of Sertoli cells in SCOS azoospermic patients.

The reduced trabecular bone mass of adult ARKO male mice results from the decreased osteogenic differentiation of bone marrow stroma cells.

Male mice with androgen receptor knock-out (ARKO) show significant bone loss at a young age. However, the lasting effect of AR inactivation on bone in aging male mice remains unclear. We designed this study to evaluate the effect of AR on bone quality in aging male mice and to find the possible causes of AR inactivation contributing to the bone loss. The mice were grouped according to their ages and AR status and their trabecular bones were examined by micro-CT analysis at 6, 12, 18, and 30 weeks old. We found that bone mass consistently decreased and the bone microarchitectures continuously deteriorated in male ARKO mice at designated time points. To determine the cause of the bone loss in ARKO mice, we further examined the role of AR in bone cell fate decision and differentiation and we conducted experiments on bone marrow stromal cells (BMSC) obtained from wild type (WT) and AR knockout (KO) mice. We found that ARKO mice had higher numbers of colony formation unit-fibroblast (CFU-F), and CD44 and CD34 positive cells in bone marrow than WT mice. Our Q-RT-PCR results showed lower expression of genes linked to osteogenesis in BMSCs isolated from ARKO mice. In conclusion, AR nullification disrupted bone microarchitecture and caused trabecular bone mass loss in male ARKO mice. And the fate of BMSCs was impacted by the loss of AR. Therefore, these findings suggest that AR may accelerate the use of progenitor cells and direct them into osteogenic differentiation to affect bone metabolism.