Resveratrol Plays a Protective Role against Premature Ovarian Failure and Prompts Female Germline Stem Cell Survival.

This study was designed to investigate the protective effect of resveratrol (RES) on premature ovarian failure (POF) and the proliferation of female germline stem cells (FGSCs) at the tissue and cell levels. POF mice were lavaged with RES, and POF ovaries were co-cultured with RES and/or GANT61 in vitro. FGSCs were pretreated with Busulfan and RES and/or GANT61 and co-cultured with M1 macrophages, which were pretreated with RES. The weights of mice and their ovaries, as well as their follicle number, were measured. Ovarian function, antioxidative stress, inflammation, and FGSCs survival were evaluated. RES significantly increased the weights of POF mice and their ovaries as well as the number of follicles, while it decreased the atresia rate of follicles. Higher levels of Mvh, Oct4, SOD2, GPx, and CAT were detected after treatment with RES in vivo and in vitro. RES treatment resulted in significantly lower TNF-α and IL-6 concentrations and an obviously higher IL-10 concentration in the ovaries. In FGSCs, higher Mvh, Oct4, and SOD2 concentrations and lower TNF-α, IL-6, and MDA concentrations were measured in the RES group. Blockage of the Hh signaling pathway reversed the protective effect of RES on FGSCs. In conclusion, RES effectively improved the ovarian function of the POF model and the productive capacity of FGSCs via relieving oxidative stress and inflammation and a mechanism involving the Hh signaling pathway, suggesting that RES is a potential agent against POF and can aid in the survival of FGSCs.

Helicobacter pylori infection downregulates duodenal CFTR and SLC26A6 expressions through TGFß signaling pathway.

BACKGROUND: The pathogenesis of Helicobacter pylori (H. pylori) infection-induced duodenal ulcer remains to be elucidated. Duodenal mucosal bicarbonate secretion is the most important protective factor against acid-induced mucosal injury. We previously revealed that H. pylori infection downregulated the expression and functional activity of duodenal mucosal cystic fibrosis transmembrane conductance regulator (CFTR) and solute linked carrier 26 gene family A6 (SLC26A6) which are the two key duodenal mucosal epithelial cellular bicarbonate transporters to mediate duodenal bicarbonate secretion. In this study, we investigated the mechanism of H. pylori infection-induced duodenal CFTR and SLC26A6 expression downregulation. RESULTS: We found that H. pylori infection induced the increase of serum transforming growth factor ß (TGFß) level and duodenal mucosal TGFß expression and the decrease of duodenal mucosal CFTR and SLC26A6 expressions in C57 BL/6 mice. The results from the experiments of human duodenal epithelial cells (SCBN) showed that H. pylori increased TGFß production and decreased CFTR and SLC26A6 expressions in SCBN cells. TGFß inhibitor SB431542 reversed the H. pylori-induced CFTR and SLC26A6 expression decreases. The further results showed that TGFß directly decreased CFTR and SLC26A6 expressions in SCBN cells. TGFß induced the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and P38 MAPK inhibitor SB203580 reversed the TGFß-induced CFTR and SLC26A6 expression decreases. CONCLUSIONS: H. pylori infection downregulates duodenal epithelial cellular CFTR and SLC26A6 expressions through TGFß-mediated P38 MAPK signaling pathway, which contributes to further elucidating the pathogenesis of H. pylori-associated duodenal ulcer.

A preliminary study on the proinflammatory mechanisms of Treponema pallidum outer membrane protein Tp92 in human macrophages and HMEC-1 cells.

AIMS: To determine proinflammatory mechanisms of Treponema pallidum outer membrane protein Tp92 in the early syphilis infection in human macrophages and HMEC-1 cells. METHODS: Recombinant Tp92 protein was used to stimulate target human macrophages and HMEC-1 cells. PDTC (Pyrrolidinedithiocarbamic acid), SB202190 and Z-YVAD-FMK were used to block the MyD88/NF-κB, MAPKs/p38 and NLRP3/Caspase-1 pathway, respectively. TNF-α, IL-1ß, IL-6, IL-8,NLRP3, casepase-1 were detected by ELISA or Western blot. Lactate dehydrogenase (LDH) activity was measured. RESULTS: Tp92 protein could significantly induced the secretion of proinflammatory cytokines TNF-α, IL-1ß, IL-6 and IL-8 in HMEC-1 cells, but not in macrophages except IL-8. When MyD88/NF-κB pathway was blocked, differences in the secretion of TNF-α, IL-6 and IL-1ß levels and LDH enzyme activity between Tp92 group and Tp92 + PDTC group were not significant (P > 0.05) in HMEC-1 cells and macrophages except IL-8(P < 0.05). When MAPKs/p38 pathway was blocked, differences in the secretion of TNF-α, IL-1ß, IL-6 and IL-8 and LDH enzyme activity both Tp92 group and Tp92 + SB2010190 group were not significant (P > 0.05) in HMEC-1 cells and macrophages. In contrast, when NLRP3/Caspase-1 pathway was blocked with Z-YVAD-FMK, TNF-α, IL-6 and IL-1ß levels, LDH enzyme activity, and Caspase-1 and NLRP3 protein levels were significantly declined (P < 0.05) in HMEC-1 cells except IL-8(P > 0.05). The LDH enzyme activity in macrophages was decreased before and after Z-YVAD-FMK blocking (P < 0.05),however, differences in the secretion of TNF-α, IL-1ß, IL-6 and IL-8 between Tp92 group and Tp92+Z-YVAD-FMK group in macrophages were not significant (P > 0.05). CONCLUSIONS: Tp92 protein may promote proinflammatory cytokines TNF-α, IL-1ß, IL-6 secretion of HMEC-1 cells, but not in macrophages, and increase the LDH enzyme activity of HMEC-1 cells and macrophages through NLRP3/Caspase-1 pathway. However, Tp92 protein may promote IL-8 secretion of HMEC-1 cells and macrophages through MyD88/NF-κB pathway.

Reversal of Direct Oral Anticoagulants: Current Status and Future Directions.

Direct oral anticoagulants (DOACs) are increasingly used for prevention and treatment of venous thromboembolism and for prevention of stroke in patients with nonvalvular atrial fibrillation. In phase III clinical trials that included more than 100,000 patients, the DOACs were at least as effective as vitamin K antagonists (VKAs) and were associated with less serious bleeding, particularly less intracranial bleeding. Real-world evidence supports these outcomes. Despite this, some physicians and patients are concerned about serious bleeding or emergencies unless specific reversal agents for the DOACs are available. However, in clinical trials performed without reversal agents, the outcome of major bleeds was similar or better in patients receiving DOACs than in those taking VKAs. Because of their short half-lives, supportive measures are sufficient to manage most bleeds in patients receiving DOACs. Anticoagulant reversal should only be considered with life-threatening bleeds, with bleeds that fail to respond to usual measures and in patients requiring urgent surgery. Idarucizumab is licensed for dabigatran reversal and andexanet alfa is likely to be soon licensed for reversal of rivaroxaban, apixaban, and edoxaban. To ensure responsible use of these agents, every hospital needs a bleeding management algorithm that identifies patients eligible for reversal and outlines appropriate dosing regimens.

Idarucizumab and factor Xa reversal agents: role in hospital guidelines and protocols.

As expected with all antithrombotic agents, there is a risk of bleeding complications in patients receiving direct oral anticoagulants (DOACs) because of the DOAC itself, acute trauma, invasive procedures, or underlying comorbidities. For many bleeding events, a prudent course of action will be to withdraw the DOAC, then "wait and support" the patient, with the expectation that the bleeding event should resolve with time. Likewise, DOAC therapy may be interrupted ahead of a planned procedure, the stopping time being dependent on the agent involved and the patient's renal function. However, urgent reversal of anticoagulation is required in patients with serious or life-threatening bleeding or in those requiring urgent surgery or procedures. Novel specific reversal agents, either under development or recently approved, will need to be incorporated into local anticoagulation reversal protocols. For dabigatran-treated patients, idarucizumab recently has been approved for clinical use in cases of life-threatening or uncontrolled bleeding or when patients require emergency surgery or urgent procedures, both associated with a high risk of bleeding. As clinical experience with individual specific reversal agents grows, their roles in managing major bleeding events in DOAC-treated patients will become better defined. Future research, as well as ongoing use of idarucizumab, should help establish when it is appropriate to re-dose with idarucizumab, coadminister with prothrombin complex concentrates, or re-initiate DOAC after idarucizumab use. Ongoing trials should help identify the appropriate doses and expected durations of effect for andexanet alfa and ciraparantag, which are likely to vary depending on the individual oral anticoagulants.

[Treatment with inhibitors of new oral direct anticoagulants in patients with severe bleedings or urgent surgical procedures. The new dabigatran antidote: the place of idarucizumab in clinical practice]. / Teendok súlyos vérzés vagy sürgos sebészeti beavatkozás esetén direkt orális antikoaguláns gyógyszerrel kezeltekben. Az új dabigatran-antidótum: idarucizumab helye a klinikai gyakorlatban.

Only vitamin K antagonists could be applied as oral anticoagulants over the past six decades. Coumarols have narrow therapeutic range, and unpredictable anticoagulant effects are resulted by multiple drug interactions. Therefore, regular routine monitoring of the international normalized ratio is necessary. There are two groups of factor-specific anticoagulants: molecules with anti-FIIa (dabigatran) and anti-FXa (rivaroxaban, apixaban and edoxaban) effect. Author summarizes the most important clinical features of the new oral anticoagulants, their indications and the possibilities of laboratory controls. Bleedings are the most important side effects of anticoagulants. This review summarizes the current published evidences for new oral anticoagulants reversal (non-specific and specific) agents, especially in cases with severe acute bleedings or urgent surgery procedures. It reports on how to use inhibitors, the recommended doses and the most important clinical results. The review focuses on idarucizumab - already approved by the U.S. Food and Drug Administration and the European Medicines Agency - which has a key role as the first specific inhibitor of dabigatran.

Effective reversal of edoxaban-associated bleeding with four-factor prothrombin complex concentrate in a rabbit model of acute hemorrhage.

BACKGROUND: Edoxaban is an oral, selective direct factor Xa inhibitor approved in Japan for venous thromboembolism prevention after orthopedic surgery. Data are lacking regarding reversal strategies for edoxaban; this study assessed whether four-factor prothrombin complex concentrate (Beriplex/Kcentra; CSL Behring GmbH, Marburg, Germany) can effectively reverse its effects on hemostasis using a previously described rabbit model. METHODS: The study comprised assessments of thrombin generation in vitro, pharmacokinetic parameters, and edoxaban reversal in vivo. In a blinded in vivo stage, a standardized kidney incision was performed in animals (n = 11 per group) randomized to receive vehicle + saline, edoxaban (1,200 µg/kg) + saline, or edoxaban (1,200 µg/kg) + four-factor prothrombin complex concentrate (50 IU/kg). Animals were monitored for treatment impact on hemostasis and coagulation parameters. Data are median (range). Statistical tests were adjusted for multiple testing. RESULTS: Edoxaban administration increased blood loss (30 [2 to 44] ml) and time to hemostasis (23 [8.5 to 30.0] min) compared with the control group (3 [1 to 8] ml and 3 [2.0 to 5.0] min, respectively). Biomarkers of coagulation (prothrombin time, activated partial thromboplastin time, whole blood clotting time) and thrombin generation parameters (e.g., peak thrombin, endogenous thrombin potential, lag time) were also affected by edoxaban. Administration of four-factor prothrombin complex concentrate significantly reduced time to hemostasis (to 8 [6.5 to 14.0] min, observed P < 0.0001) and total blood loss (to 9 [4 to 22] ml, observed P = 0.0050) compared with the edoxaban + saline group. Of the biomarkers tested, prothrombin time, whole blood clotting time, and endogenous thrombin potential correlated best with clinical parameters. CONCLUSION: In a rabbit model of hemostasis, four-factor prothrombin complex concentrate administration significantly decreased edoxaban-associated hemorrhage.

Involvement of serotonergic system in the effect of a metabotropic glutamate 5 receptor antagonist in the novelty-suppressed feeding test.

The blockade of metabotropic glutamate 5 (mGlu5) receptor has been reported to exert antidepressant effects in several animal models. We previously reported that both ketamine and an mGlu5 receptor antagonist exerted an effect in a novelty-suppressed feeding (NSF) test, and that the effect of ketamine may be mediated through an α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor-dependent increase in serotonergic transmission. However, the involvement of the serotonergic system in the effect of mGlu5 receptor antagonists in the NSF test is not well understood. Therefore, we examined the roles of the serotonergic system in the effect of an mGlu5 receptor antagonist, 6-methyl-2-(phenylethynyl)pyridine hydrochloride (MPEP), in the NSF test in mice. The administration of MPEP significantly shortened the latency to feed, which was not attenuated by the AMPA receptor antagonist, 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide (NBQX). The effect of MPEP was abolished by the tryptophan hydroxylase inhibitor, para-chlorophenylalanine (PCPA). Moreover, the effect of MPEP was blocked by a serotonin (5-HT)2A/2C receptor antagonist, ritanserin, but not by a 5-HT1A receptor antagonist, N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridynyl) cyclohexane-carboxamide (WAY100635). These results suggest that the effect of an mGlu5 receptor antagonist may be mediated by the serotonergic system, including the stimulation of the 5-HT2A/2C receptor, in an AMPA receptor-independent manner in the NSF test.

Soluble guanylate cyclase redox state under hypoxia or hypoxia/reoxygenation in isolated monkey coronary arteries.

Hypoxia or hypoxia/reoxygenation impairs nitric oxide (NO)-mediated relaxation through the increase in superoxide generation in monkey coronary arteries. Soluble guanylate cyclase (sGC), the target enzyme of NO, has been shown to change from the NO-sensitive reduced form to the NO-insensitive oxidized/heme-free form under substantial oxidative stress, so the present study investigated whether hypoxia or hypoxia/reoxygenation influences sGC redox equilibrium. In isolated monkey coronary arteries without endothelium, the relaxation caused by the sGC stimulator BAY 41-2272 (Emax: 93.3% ± 2.2%) was somewhat impaired under hypoxia (Emax: 86.3% ± 2.6%) or hypoxia/reoxygenation (Emax: 86.1% ± 3.2%), whereas that by the sGC activator BAY 60-2770 (Emax: 86.0% ± 3.2%) was significantly augmented under hypoxia (Emax: 94.4% ± 1.3%) or hypoxia/reoxygenation (Emax: 95.5% ± 1.1%). In addition, cGMP formation in response to BAY 41-2272 and BAY 60-2770 was inhibited and stimulated, respectively, under hypoxia or hypoxia/reoxygenation. The effects of hypoxia or hypoxia/reoxygenation on BAY 41-2272- and BAY 60-2770-induced vasorelaxation were completely canceled by the treatment with the superoxide dismutase mimetic tempol. These findings suggest that sGC redox equilibrium in the coronary artery is shifted towards the NO-insensitive form under hypoxia or hypoxia/reoxygenation and that superoxide seems to play an important role in this shift.

Prothrombin complex concentrates and a specific antidote to dabigatran are effective ex-vivo in reversing the effects of dabigatran in an anticoagulation/liver trauma experimental model.

INTRODUCTION: New oral anticoagulants are effective alternatives to warfarin. However, no specific reversal agents are available for life-threatening bleeding or emergency surgery. Using a porcine model of trauma, this study assessed the ability of prothrombin complex concentrate (PCC), activated PCC (aPCC), recombinant FVIIa (rFVIIa) and a specific antidote to dabigatran (aDabi-Fab) to reverse the anticoagulant effects of dabigatran. METHODS: Dabigatran etexilate (DE) was given orally for 3 days (30 mg/kg bid) and intravenously on day 4 to achieve consistent, supratherapeutic concentrations of dabigatran. Blood samples were collected at baseline, after oral DE, after intravenous dabigatran, and 60 minutes post-injury. PCC (30 and 60 U/kg), aPCC (30 and 60 U/kg), rFVIIa (90 and 180 µg/kg) and antidote (60 and 120 mg/kg) were added to blood samples ex-vivo. Coagulation was assessed by thromboelastometry, global coagulation assays and diluted thrombin time. RESULTS: Plasma concentrations of dabigatran were 380 ± 106 ng/ml and 1423 ± 432 ng/ml after oral and intravenous administration, respectively, and all coagulation parameters were affected by dabigatran. Both PCCs and aDabi-Fab, but not rFVIIa, reversed the effects of dabigatran on thromboelastometry parameters and prothrombin time. In contrast, aPTT was only normalised by aDabi-Fab. Plasma concentration (activity) of dabigatran remained elevated after PCC and rFVIIa therapy, but was not measureable after aDabi-Fab. CONCLUSION: In conclusion, PCC and aPCC were effective in reducing the anticoagulant effects of dabigatran under different conditions, while aDabi-Fab fully corrected all coagulation measures and decreased the plasma concentration of dabigatran below the limit of detection. No significant effects were observed with rFVIIa.

Functional and structural interaction of (-)-reboxetine with the human α4ß2 nicotinic acetylcholine receptor.

The interaction of the selective norepinephrine reuptake inhibitor (-)-reboxetine with the human α4ß2 nicotinic acetylcholine receptor (nAChR) in different conformational states was studied by several functional and structural approaches. Patch-clamp and Ca(2+)-influx results indicate that (-)-reboxetine does not activate hα4ß2 nAChRs via interaction with the orthosteric sites, but inhibits agonist-induced hα4ß2 activation by a noncompetitive mechanism. Consistently, the results from the electrophysiology-based functional approach suggest that (-)-reboxetine may act via open channel block; therefore, it is capable of producing a use-dependent type of inhibition of the hα4ß2 nAChR function. We tested whether (-)-reboxetine binds to the luminal [(3)H]imipramine site. The results indicate that, although (-)-reboxetine binds with low affinity to this site, it discriminates between the resting and desensitized hα4ß2 nAChR ion channels. Patch-clamp results also indicate that (-)-reboxetine progressively inhibits the hα4ß2 nAChR with two-fold higher potency at the end of one-second application of agonist, compared with the peak current. The molecular docking studies show that (-)-reboxetine blocks the ion channel at the level of the imipramine locus, between M2 rings 6' and 14'. In addition, we found a (-)-reboxetine conformer that docks in the helix bundle of the α4 subunit, near the middle region. According to molecular dynamics simulations, (-)-reboxetine binding is stable for both sites, albeit less stable than imipramine. The interaction of these drugs with the helix bundle might alter allostericaly the functionality of the channel. In conclusion, the clinical action of (-)-reboxetine may be produced (at least partially) by its inhibitory action on hα4ß2 nAChRs.

Serotonin antagonists in the five-choice serial reaction time task and their interactions with nicotine.

Much research has implicated the serotonin (5-HT) system in cognitive functioning and psychomotor stimulant abuse, but its role depends on the subtypes of 5-HT receptors involved and the nature of the behavioural task. Here we aimed to extend previous studies by examining the role of 5-HT1A and 5-HT2C receptors in attentional performance. The effects of the selective 5-HT antagonists WAY-100635 and SB-242084 were assessed alone and for interactions with nicotine in the five-choice serial reaction time task in rats. The effects of several doses of WAY-100635 were tested in combination with a fixed dose of nicotine, and then various doses of nicotine were tested in combination with SB-242084. Systemic administration of WAY-100635 and SB-242084 induced opposing effects on speed-related measures in the five-choice serial reaction time task, with antagonism at 5-HT1A receptors increasing omission errors and response latency, and antagonism at 5-HT2C receptors reducing both omissions and latency, and also increasing anticipatory responses; neither drug affected accuracy. Nicotine itself improved all main indices of attention, and there was preliminary evidence that the detrimental effects of WAY-100635 on response latency were weakened by nicotine. Conversely, treatment with SB-242084 enhanced all speed-related indices of performance to above the levels seen under the influence of nicotine alone, thus suggesting that 5-HT2C antagonists might be useful to decrease reaction times if used as an add-on therapy to treat attentional decline.

The role of α1 and α5 subunit-containing GABAA receptors in motor impairment induced by benzodiazepines in rats.

Benzodiazepines negatively affect motor coordination and balance and produce myorelaxation. The aim of the present study was to examine the extent to which populations of γ-aminobutyric acid A (GABAA) receptors containing α1 and α5 subunits contribute to these motor-impairing effects in rats. We used the nonselective agonist diazepam and the α1-selective agonist zolpidem, as well as nonselective, α1-subunit and α5-subunit-selective antagonists flumazenil, ßCCt, and XLi093, respectively. Ataxia and muscle relaxation were assessed by rotarod and grip strength tests performed 20 min after intraperitoneal treatment. Diazepam (2 mg/kg) induced significant ataxia and muscle relaxation, which were completely prevented by pretreatment with flumazenil (10 mg/kg) and ßCCt (20 mg/kg). XLi093 antagonized the myorelaxant, but not the ataxic actions of diazepam. All three doses of zolpidem (1, 2, and 5 mg/kg) produced ataxia, but only the highest dose (5 mg/kg) significantly decreased the grip strength. These effects of zolpidem were reversed by ßCCt at doses of 5 and 10 mg/kg, respectively. The present study demonstrates that α1 GABAA receptors mediate ataxia and indirectly contribute to myorelaxation in rats, whereas α5 GABAA receptors contribute significantly, although not dominantly, to muscle relaxation but not ataxia.

5-(5-(6-[(11)C]methyl-3,6-diazabicyclo[3.2.0]heptan-3-yl)pyridin-2-yl)-1H-indole as a potential PET radioligand for imaging cerebral α7-nAChR in mice.

The radiosynthesis and in vivo evaluation of 5-(5-(6-[(11)C]methyl-3,6-diazabicyclo[3.2.0]heptan-3-yl)pyridin-2-yl)-1H-indole [(11)C]rac-(1), a potential PET tracer for α7 nicotinic acetylcholine receptors (α7-nAChR), are described. Syntheses of the nonradioactive standard rac-1 and corresponding desmethyl precursor 7 were achieved in several reaction steps. Radiomethylation of 7 with [(11)C]CH(3)I afforded [(11)C]rac-1 in an average radiochemical yield of 30 ± 5% (n=5) with high radiochemical purity and an average specific radioactivity of 444 ± 74 GBq/µmol (n=5). The total synthesis time was 30 min from end-of-bombardment. Biodistribution studies in mice showed that [(11)C]rac-1 penetrates the blood-brain barrier and specifically labels neuronal α7-nAChRs.

Captopril attenuates hypertension and renal injury induced by the vascular endothelial growth factor inhibitor sorafenib.

Vascular endothelial growth factor inhibitors (VEGFi) are known to cause hypertension and renal injury that severely limits their use as an anticancer therapy. We hypothesized that the angiotensin-converting enzyme inhibitor captopril not only prevents hypertension, but also decreases renal injury caused by the VEGFi sorafenib. Rats were administered sorafenib (20 mg/kg per day) alone or in combination with captopril (40 mg/kg per day) for 4 weeks. Sorafenib administration increased blood pressure, which plateaued by day 10. Concurrent treatment with captopril for 4 weeks resulted in a 30 mmHg decrease in blood pressure compared with sorafenib alone (155 ± 5 vs 182 ± 6 mmHg, respectively; P < 0.05). Furthermore, concurrent captopril treatment reduced albuminuria by 50% compared with sorafenib alone (20 ± 8 vs 42 ± 9 mg/day, respectively; P < 0.05) and reduced nephrinuria by eightfold (280 ± 96 vs 2305 ± 665 µg/day, respectively; P < 0.05). Glomerular injury, thrombotic microangiopathy and tubular cast formation were also decreased in captopril-treated rats administered sorafenib. Renal autoregulatory efficiency was determined by evaluating the afferent arteriolar constrictor response to ATP. Sorafenib administration attenuated the vasoconstriction to ATP, whereas concurrent captopril treatment improved ATP reactivity. In conclusion, captopril attenuated hypertension and renal injury and improved renal autoregulatory capacity in rats administered sorafenib. These findings indicate that captopril treatment, in addition to alleviating the detrimental side-effect of hypertension, decreases the renal injury associated with anticancer VEGFi therapies such as sorafenib.

Anxiolytic- and antidepressant-like effects of new phenylpiperazine derivative LQFM005 and its hydroxylated metabolite in mice.

The current treatments available for anxiety and depression are only palliative. Full remission has remained elusive, characterizing unmet medical needs. In the scope of an academic drug discovery program, we describe here the design, synthesis, in vitro metabolism prediction and pharmacological characterization of a new piperazine compound, 1-(4-methoxyphenyl)-4-((1-phenyl-1H-pyrazol-4-yl)methyl)piperazine (LQFM005), and of its main putative metabolite, 4-(4-((4-(4-methoxyphenyl)piperazin-1-yl)methyl)- 1H-pyrazol-1-yl)phenol (LQFM235). The production of the metabolite was initially performed by in vitro biotransformation of LQFM005 using Aspergillus candidus and then by chemical synthesis. Oral administration of either 12 or 24 µmol/kg LQFM005 to mice did not affect spontaneous locomotor activity but increased the time spent in the center of the open field. Both LQFM005 and LQFM235 (24 µmol/kg) increased the time spent by the mice in the open arms of the elevated plus maze (EPM), a good indication of anxiolytic-like effect, and decreased the immobility time in the forced swimming test (FST), suggesting an antidepressant-like effect. The previous administration of WAY-100635 (a 5-HT1A antagonist) abolished the effects of LQFM005 in both EPM and FST. Binding experiments showed that LQFM005 and its metabolite bind to the 5-HT1A receptor with a moderate affinity (Ki around 5-9 µM). The two compounds are relatively safe, as indicated by cytotoxic assessment using the 3T3 fibroblast cell line and estimated LD50 around 600 mg/kg. In conclusion, oral administration of the newly synthesized phenylpiperazines produced anxiolytic- and antidepressant-like effects in behavioral tests, putatively in part through the activation of 5-HT1A receptors.

A practical synthesis of renin inhibitor MK-1597 (ACT-178882) via catalytic enantioselective hydrogenation and epimerization of piperidine intermediate.

A practical enantioselective synthesis of renin inhibitor MK-1597 (ACT-178882), a potential new treatment for hypertension, is described. The synthetic route provided MK-1597 in nine steps and 29% overall yield from commercially available p-cresol (7). The key features of this sequence include a catalytic asymmetric hydrogenation of a tetrasubstituted ene-ester, a highly efficient epimerization/saponification sequence of 4 which sets both stereocenters of the molecule, and a short synthesis of amine fragment 2.