Potent and Selective Human 5-HT Serotonin Receptor Antagonists: 4'-Cyano-(N)-methanocarba-adenosines by Synthetic Serendipity.

Rigidified nucleoside derivatives with (N)-methanocarba replacement of ribose have been repurposed as peripheral subtype-selective 5-HT serotonin receptor antagonists for heart and lung fibrosis and intestinal/vascular conditions. 4'-Cyano derivative (MRS8209; , 4.27 nM) was 47-fold (human binding, but not rat and mouse) and 724-fold (functionally) selective at 5-HTR, compared to antitarget 5-HTR, and predicted to form a stable receptor complex using docking and molecular dynamics.

Bioisosteric analogs of MDMA: Improving the pharmacological profile?

3,4-Methylenedioxymethamphetamine (MDMA, 'ecstasy') is re-emerging in clinical settings as a candidate for the treatment of specific neuropsychiatric disorders (e.g. post-traumatic stress disorder) in combination with psychotherapy.

-(4-Bromo-2,5-Dimethoxyphenethyl)-6-(4-Phenylbutoxy)Hexan-1-Amine (XOB): A Novel Phenylalkylamine Antagonist of Serotonin 2A Receptors and Voltage-Gated Sodium Channels.

Bipolar disorder impacts millions of patients in the United States but the mechanistic understanding of its pathophysiology and therapeutics is incomplete. Atypical antipsychotic serotonin (5-HT) receptor antagonists, such as quetiapine and olanzapine, and mood-stabilizing voltage-gated sodium channel (VGSC) blockers, such as lamotrigine, carbamazepine, and valproate, show therapeutic synergy and are often prescribed in combination for the treatment of bipolar disorder. Combination therapy is a complex task for clinicians and patients, often resulting in unexpected difficulties with dosing, drug tolerances, and decreased patient compliance.

Bioisosteric analogs of MDMA with improved pharmacological profile.

3,4-Methylenedioxymethamphetamine (MDMA, ' ) is re-emerging in clinical settings as a candidate for the treatment of specific psychiatric disorders (e.g. post-traumatic stress disorder) in combination with psychotherapy.

Identification of 5-HT receptor signaling pathways associated with psychedelic potential.

Serotonergic psychedelics possess considerable therapeutic potential. Although 5-HT receptor activation mediates psychedelic effects, prototypical psychedelics activate both 5-HT-Gq/11 and β-arrestin2 transducers, making their respective roles unclear. To elucidate this, we develop a series of 5-HT-selective ligands with varying Gq efficacies, including β-arrestin-biased ligands.

Functional profiling of the G protein-coupled receptor C3aR1 reveals ligand-mediated biased agonism.

G protein-coupled receptors (GPCRs) are leading druggable targets for several medicines, but many GPCRs are still untapped for their therapeutic potential due to poor understanding of specific signaling properties. The complement C3a receptor 1 (C3aR1) has been extensively studied for its physiological role in C3a-mediated anaphylaxis/inflammation, and in TLQP-21-mediated lipolysis, but direct evidence for the functional relevance of the C3a and TLQP-21 ligands and signal transduction mechanisms are still limited. In addition, C3aR1 G protein coupling specificity is still unclear, and whether endogenous ligands, or drug-like compounds, show ligand-mediated biased agonism is unknown.

Identification of 5-HT Receptor Signaling Pathways Responsible for Psychedelic Potential.

Serotonergic psychedelics possess considerable therapeutic potential. Although 5-HT receptor activation mediates psychedelic effects, prototypical psychedelics activate both 5-HT-Gq/11 and β-arrestin2 signaling, making their respective roles unclear. To elucidate this, we developed a series of 5-HT-selective ligands with varying Gq efficacies, including β-arrestin-biased ligands.

Structure activity relationships of 5-HT and 5-HT serotonin receptor antagonists: N, C2 and 5'-Modified (N)-methanocarba-adenosine derivatives.

(N)-Methanocarba adenosine derivatives were structurally modified to target 5-HT serotonin receptors as antagonists, predominantly containing branched N-alkyl groups. N-Dicycloalkyl-methyl groups, including their asymmetric variations, as well as 2-iodo, were found to generally favor 5-HTRs, while only N-dicyclohexyl-methyl derivative 35 showed weak 5-HTR affinity (K 3.6 μM).

Pharmacological Mechanism of the Non-hallucinogenic 5-HT Agonist Ariadne and Analogs.

Ariadne is a non-hallucinogenic analog in the phenylalkylamine chemical class of psychedelics that is closely related to an established synthetic hallucinogen, 2,5-dimethoxy-4-methyl-amphetamine (DOM), differing only by one methylene group in the α-position to the amine. Ariadne has been tested in humans including clinical trials at Bristol-Myers Company that indicate a lack of hallucinogenic effects and remarkable therapeutic effects, such as rapid remission of psychotic symptoms in schizophrenics, relaxation in catatonics, complete remission of symptoms in Parkinson's disease (PD), and improved cognition in geriatric subjects. Despite these provocative clinical results, the compound has been abandoned as a drug candidate and its molecular pharmacology remained unknown.

Darbepoetin alpha in lower-than-equimolar doses maintains haemoglobin levels in stable haemodialysis patients converting from epoetin alpha/beta.

Background: The conversion of patients on stable epoetin therapy to darbepoetin alpha is usually carried out according to the '1 microg darbepoetin =200 U epoetin' rule, which is based on the protein content of the two compounds. Since several observations have suggested that this conversion factor leads to an overestimate of the required darbepoetin dose, the present multicentre study was designed to assess the true conversion ratio by prospectively evaluating the change in darbepoetin alpha dose after conversion from epoetin, which was required to keep haemoglobin (Hb) stable.

Methods: Haemodialysis patients with stable Hb and maintained on either s.

Steroid-resistant kidney transplant rejection: diagnosis and treatment.

Decreases in transplant function may be attributable to a variety of conditions, including prerenal and postrenal failure, cyclosporin A (CsA) toxicity, polyoma nephritis, recurrent glomerulonephritis, and rejection. The diagnosis of rejection should therefore be made on the basis of a transplant biopsy of adequate size, before the initiation of any therapy. Pulse steroid treatment (three to five 0.

Pathogenesis of acute renal failure: new aspects.

Based on 2 case presentations - acute renal failure (ARF) due to myeloma kidney and due to angiotensin-converting enzyme inhibitor administration in the presence of transplant artery stenosis - new aspects in the pathogenesis of ARF are presented and discussed. The multifactorial pathogenesis of ARF includes (a) a disturbance of glomerular microcirculation (afferent and perhaps mesangial constriction, inadequate efferent dilatation); (b) a disturbance of medullary microcirculation (medullary capillary congestion) attributed to a combination of endothelial damage and tubular dilatation; (c) tubular cell damage which, though rarely in humans justifying the term 'acute tubular necrosis', promotes both backleak of glomerular filtrate and shedding of brush border vesicles; (d) the latter promotes tubular obstruction by casts which consist of Tamm-Horsfall protein and brush border components. Once ARF is established, repair processes set in which appear to depend on growth factors such as epidermal growth factor and insulin-like growth factor 1, of which there is a relative shortage in established ARF.

Monoclonal gammopathy after intense induction immunosuppression in renal transplant patients.

Objectives: Incidence and risk factors of post-transplant monoclonal gammopathy were studied in renal transplant patients who received their grafts between 1982 and 1992 (n = 390 grafts). Immunoelectrophoresis was performed at annual intervals after transplantation.

Results: Forty-six cases of clonal gammopathy were detected: 35 monoclonal, 11 bi- or triclonal, with a predominance of IgG and kappa light-chain subtypes (IgG, 39; IgA, 3; IgM, 4; kappa, 35; lambda, 19).

Hyperuricaemia in cyclosporin-treated patients: GFR-related effect.

Background: Hyperuricaemia is a well known side-effect of cyclosporin A (CsA) treatment. The pathogenic mechanisms, however, remain controversial. There is no convincing evidence that hyperuricaemia is due to CsA-induced, impaired tubular handling of uric acid.

[Follow-up care of living kidney donors].

The follow-up of living kidney donors demands medical as well as psychological competence. In the postoperative period, attention focuses on pain management, early detection of wound complications and the prophylaxis of thromboembolism. Regular visits of the donor who may easily feel neglected should be as much part of the transplant team's post-operative routine as visits of the recipient.

A randomized prospective trial of prophylactic immunosuppression with ATG-fresenius versus OKT3 after renal transplantation.

We carried out a randomized prospective trial to compare OKT3 (5 mg/d, 51 patients) with ATG-Fresenius (ATG-F, 4 mg/kg/d, 53 patients) for induction therapy after renal transplantation, concerning side effects, rejection, and infection incidence within a one year follow-up period. Concomitant immunosuppression included azathioprine/steroids from day 0 and cyclosporine A from day 4. OKT3 patients experienced significantly more and more-severe side effects, particularly pyrexia, headache, and pulmonary fluid overload.

ET-1 excretion is urine flow-dependent in kidney donors and transplant recipients.

Urinary endothelin-1 excretion (uET-1/min) has been reported to be elevated under cyclosporin A (CsA) therapy in kidney transplant recipients (KR). The possible flow-dependence of uET-1/min was not considered. Therefore, we studied the effect of water diuresis on uET-1/min in KR 1 year after transplantation and used kidney donors (KD) as controls.

Weight-independent dosing of cyclosporine--an alternative to the "mg/kg" doctrine.

Cyclosporine is usually prescribed as "mg CsA per kg body weight", and blood levels are used for guiding CsA therapy. The present study evaluated whether it is sensible to dose in "mg/kg" if one wishes to obtain specific CsA blood levels. In a retrospective analysis, 1071 consecutive CsA whole-blood trough levels from 164 renal transplant patients, measured by monoclonal parent RIA, were correlated with the respective oral CsA doses and several demographic parameters, including gender, age, weight, height, and time after transplantation.

Excellent uricosuric efficacy of benzbromarone in cyclosporin-A-treated renal transplant patients: a prospective study.

Patients on cyclosporin A (CsA) often develop hyperuricaemia and gout. In transplant patients the use of uricosuric drugs for treating hyperuricaemia may be preferable to allopurinol because of the known interaction of the latter with azathioprine. We therefore prospectively studied the uricosuric efficacy of 100 mg benzbromarone (Bbr;Desuric) daily in 25 CsA-treated renal transplant patients with stable graft function and hyperuricaemia (> 359 mumol/l for females, > 491 mumol/l for males).