Evolutionary Sequence Modeling for Discovery of Peptide Hormones

There are currently a large number of “orphan” G-protein-coupled receptors (GPCRs) whose endogenous ligands (peptide hormones) are unknown. Identification of these peptide hormones is a difficult and important problem. We describe a computational framework that models spatial structure along the genomic sequence simultaneously with the temporal evolutionary path structure across species and show how such models can be used to discover new functional molecules, in particular peptide hormones, via cross-genomic sequence comparisons. The computational framework incorporates a priori high-level knowledge of structural and evolutionary constraints into a hierarchical grammar of evolutionary probabilistic models. This computational method was used for identifying novel prohormones and the processed peptide sites by producing sequence alignments across many species at the functional-element level. Experimental results with an initial implementation of the algorithm were used to identify potential prohormones by comparing the human and non-human proteins in the Swiss-Prot database of known annotated proteins. In this proof of concept, we identified 45 out of 54 prohormones with only 44 false positives. The comparison of known and hypothetical human and mouse proteins resulted in the identification of a novel putative prohormone with at least four potential neuropeptides. Finally, in order to validate the computational methodology, we present the basic molecular biological characterization of the novel putative peptide hormone, including its identification and regional localization in the brain. This species comparison, HMM-based computational approach succeeded in identifying a previously undiscovered neuropeptide from whole genome protein sequences. This novel putative peptide hormone is found in discreet brain regions as well as other organs. The success of this approach will have a great impact on our understanding of GPCRs and associated pathways and help to identify new targets for drug development

Effect of mavoglurant (AFQ056) on the pharmacokinetics of a combined oral contraceptive containing ethinyl estradiol and levonorgestrel in healthy women

Objective: To compare the pharmacokinetics (PKs) of a combination oral contraceptive (OC) when given alone or concomitantly with the selective metabotropic glutamate receptor 5 antagonist mavoglurant (AFQ056). Methods: This open-label, fixed-sequence, two-period study included 30 healthy female subjects aged 18–40 years. In Period 1, a single oral dose of an OC containing 30 μg ethinyl estradiol (EE)/150 μg levonorgestrel (LNG) was administered alone. In Period 2, OC was administered with a clinically relevant multiple-dose of 100 mg b.i.d. mavoglurant under-steady conditions. Plasma concentrations of EE and LNG were measured up to 72 hours post administration and PK parameters Cmax and AUClast were estimated using noncompartmental methods. Results: The geometric mean ratios of EE PK parameters Cmax and AUClast obtained with and without mavoglurant were 0.97 (90% confidence interval [CI]: 0.90-1.06) and 0.94 (90% CI: 0.86-1.03), respectively. The corresponding Cmax and AUClast for LNG were 0.81 (90% CI: 0.75-0.87) and 0.68 (90% CI: 0.63 0.73), respectively. Conclusions: In conclusion, the EE PK was unchanged, whereas Cmax and AUClast of LNG was approximately 19% and 32% lower, respectively, when given with mavoglurant. Further investigation regarding the impact on contraceptive efficacy is warranted

Efficacy, Safety and Tolerability of AFQ056 for the treatment of chorea in patients with Huntington’s disease

OBJECTIVE To assess the anti-choreatic efficacy, safety and tolerability of AFQ056 in Huntington’s disease (HD). BACKGROUND HD is characterised by involuntary choreatic movements. Treatments of chorea have limited efficacy and side effects. AFQ056, a selective metabotropic glutamate-receptor-5 antagonist shown to reduce levodopa-induced dyskinesia in Parkinson’s disease, was hypothesized to reduce chorea in HD. DESIGN/METHODS 32-day, randomized, double-blind, parallel-group, placebo-controlled, proof-of-concept study. Patients were 30–85 years, with HD (CAG≥36) in clinical stage I–III, and a Unified HD Rating Scale-Total Motor Score (UHDRS-TMS) maximal chorea sum score >10. Patients were randomized (1:1) to AFQ056 (Days 1–12, titration from 25mg to 150mg twice-daily [bid]; Days 13–28, maintenance [150mg bid]; Days 29–32, down-titration [50 mg bid]) or placebo. Primary objectives were to assess the efficacy of AFQ056 versus placebo at Day 28 on the UHDRS-TMS maximal chorea sum score and the orientation index (non-dominant hand) from the quantitative-motor (Q-Motor) grasping task; and to evaluate safety and tolerability of AFQ056. Key secondary efficacy assessments included total UHDRS-TMS, UHDRS-TMS luria score, UHDRS-TMS finger taps, and additional Q-Motor measures. RESULTS 42 patients (mean age 55.2 years, HD duration 6.6 years) were randomized. At Day 28, there were no significant improvements on the UHDRS-TMS maximal chorea sum score (p=0.155) or orientation index (non-dominant hand, p=0.626) in AFQ056-treated patients versus placebo. A significant reduction in Q-Motor speeded-tapping variability was observed favouring AFQ056 versus placebo and reverting at study end ; this was accompanied by UHDRS-TMS finger-tapping scores exhibiting a trend towards improvement. No significant treatment effects were observed at Day 28 on other key secondary assessments. CONCLUSIONS AFQ056 did not reduce involuntary choreatic movements in HD. The Q-Motor finding in speeded-tapping may reflect an improvement in fine motor coordination, but the clinical relevance of this observation is unknown. Overall, AFQ056 was well-tolerated in HD

A randomized, placebo‐controlled trial of AFQ056 for the treatment of chorea in Huntington's disease

Background This study investigated the hypothesis that AFQ056 (mavoglurant), a selective metabotropic glutamate receptor 5 antagonist, reduces chorea in Huntington's disease (HD). Methods This 32-day randomized, double-blind, parallel-group, proof-of-concept study investigated AFQ056 (25-150 mg [incremental doses], twice-daily) versus placebo in patients with HD. Primary efficacy assessments were the chorea-sum score and orientation index (nondominant hand) from the quantitative motor (Q-Motor) grasping task at day 28. Key secondary efficacy assessments included finger-tapping in the Unified Huntington's Disease Rating Scale–Total Motor Score and Q-Motor measures. Safety and tolerability were assessed. Results Overall, 42 patients were randomized. At day 28, no improvement was observed on the primary efficacy assessments (P > 0.10) with AFQ056 versus placebo. The Q-Motor speeded-tapping interonset interval variability was reduced with AFQ056 versus placebo for the nondominant hand (P = 0.01). The incidence of adverse events was 66.7% with AFQ056 and 57.1% with placebo. Conclusions AFQ056 did not reduce choreatic movements in HD, but was well tolerated. The clinical relevance of the Q-Motor findings (speeded-tapping) are unknown and may warrant further investigation. © 2015 International Parkinson and Movement Disorder Societ

A randomized, placebo-controlled trial of AFQ056 for the treatment of chorea in Huntington's disease

Background This study investigated the hypothesis that AFQ056 (mavoglurant), a selective metabotropic glutamate receptor 5 antagonist, reduces chorea in Huntington's disease (HD). Methods This 32-day randomized, double-blind, parallel-group, proof-of-concept study investigated AFQ056 (25-150 mg [incremental doses], twice-daily) versus placebo in patients with HD. Primary efficacy assessments were the chorea-sum score and orientation index (nondominant hand) from the quantitative motor (Q-Motor) grasping task at day 28. Key secondary efficacy assessments included finger-tapping in the Unified Huntington's Disease Rating Scale–Total Motor Score and Q-Motor measures. Safety and tolerability were assessed. Results Overall, 42 patients were randomized. At day 28, no improvement was observed on the primary efficacy assessments (P > 0.10) with AFQ056 versus placebo. The Q-Motor speeded-tapping interonset interval variability was reduced with AFQ056 versus placebo for the nondominant hand (P = 0.01). The incidence of adverse events was 66.7% with AFQ056 and 57.1% with placebo. Conclusions AFQ056 did not reduce choreatic movements in HD, but was well tolerated. The clinical relevance of the Q-Motor findings (speeded-tapping) are unknown and may warrant further investigation. © 2015 International Parkinson and Movement Disorder Societ

Convergence of multiple pelvic organ inputs in the rat rostral medulla

Electrophysiological recordings were used to investigate the degree of pelvic/visceral convergent inputs onto single medullary reticular formation (MRF) neurons. A total of 94 MRF neurons responsive to bilateral electrical stimulation of the pelvic nerve (PN) in 12 urethane-anaesthetized male rats were tested for responses to mechanical stimulation of the urinary bladder, urethra, colon and penis, and electrical stimulation of the dorsal nerve of the penis (DNP) and abdominal branches of the vagus. Responses to distension of the bladder were found for 51% (n = 48) of the MRF neurons tested. Of these 48, 71% responded to urethral infusion, 81% responded to colon distension, 100% responded to penile stimulation (and DNP), and 85% responded to vagal stimulation, with 62% responding to stimulation of all four of these territories. This high degree of visceral convergence (i.e. 62%) in a subset of PN-responsive MRF neurons is significantly greater than for the subset of PN-responsive MRF neurons that did not respond to urinary bladder distension (i.e. out of the 46 remaining neurons, none responded to all four of the other pelvic/visceral stimuli combined). These results suggest that the neurons processing information from the urinary bladder at this level of the neural axis are likely to be important for mediating interactions between different visceral organs for the coordination of multiple pelvic/visceral functions