Improving natural product research translation: From source to clinical trial.

While great interest in health effects of natural product (NP) including dietary supplements and foods persists, promising preclinical NP research is not consistently translating into actionable clinical trial (CT) outcomes. Generally considered the gold standard for assessing safety and efficacy, CTs, especially phase III CTs, are costly and require rigorous planning to optimize the value of the information obtained. More effective bridging from NP research to CT was the goal of a September, 2018 transdisciplinary workshop. Participants emphasized that replicability and likelihood of successful translation depend on rigor in experimental design, interpretation, and reporting across the continuum of NP research. Discussions spanned good practices for NP characterization and quality control; use and interpretation of models (computational through in vivo) with strong clinical predictive validity; controls for experimental artefacts, especially for in vitro interrogation of bioactivity and mechanisms of action; rigorous assessment and interpretation of prior research; transparency in all reporting; and prioritization of research questions. Natural product clinical trials prioritized based on rigorous, convergent supporting data and current public health needs are most likely to be informative and ultimately affect public health. Thoughtful, coordinated implementation of these practices should enhance the knowledge gained from future NP research.

Chris Cornell, the Black Hole Sun, and the Seasonality of Suicide.

PURPOSE: Seattle-inspired rock and roll superstar Chris Cornell died by suicide in May 2017. In the northern hemisphere, May represents the peak of the widely replicated but still unexplained seasonal spring rhythm in suicide. Years earlier, Cornell had suffered openly from recurrent bouts of severe depression, and his early musical lyrics do indeed suggest an enduring sensitivity to the vicissitudes of depressed and suicidal states. Cornell's most famous song, Black Hole Sun, suggests a mixed mood state, the incidence of which also peaks in the spring. The present work explores Cornell's May suicide from a chronobiologic perspective. METHODS: Review of Cornell's lyrics and literature on suicide. RESULTS: Cornell's lyrics contain clear indicators of mixed depressive and seasonal imagery, highlighting 3 fundamental axioms of suicidology: (1) the yearly suicide rhythm peaks in May in the northern hemisphere, (2) mixed depressive states are particularly lethal, and (3) the suicide risk increases dramatically when recovering from depression and mood turns mixed. CONCLUSIONS: Cornell, in his life and music, left us with a novel and important hypothesis about the spring seasonality of suicide, namely, that the yearly suicide risk becomes maximal when winter turns to spring and there emerges a deadly mixed mood state under a May photoperiod, i.e., the suicide risk is maximal when a Black Hole Sun occurs in May. It is hoped that Cornell's legacy and sensitive hypothesis inspire research into the etiology and treatment of the spring seasonality of suicide risk and mixed mood states. LIMITATIONS: The Cornell hypothesis was formulated based in part on several speculative inferences regarding the course of his functioning just prior to his suicide.

A Phase I, Randomized, Double-Blind, Laser-Evoked Potential Study to Evaluate the Analgesic/Antihyperalgesic Effect of ASP9226, a State-Dependent N-Type Voltage-Gated Calcium Channel Inhibitor, in Healthy Male Subjects.

Objective: Evaluate the analgesic/antihyperalgesic effects of ASP9226, a state-dependent N-type voltage-gated calcium channel inhibitor, in healthy male subjects. Design: Randomized, double-blind, double-dummy, placebo- and active comparator-controlled crossover study. Setting: HPR Dr. Schaffler GmbH, Munich, Germany. Subject: Healthy male subjects aged 18-55 years. Methods: Twenty-four eligible subjects were randomly assigned to one of four treatment sequences and received single doses of ASP9226 (30 mg or 50 mg), pregabalin (150 mg), or placebo during four treatment periods. Laser-evoked potentials (LEP) and postlaser pain visual analog scales (VAS) on capsaicin-treated skin were assessed during main assessment days (the first day of each study period). Primary and secondary end points were the differences in LEP N2-P2 peak-to-peak (PtP) amplitudes and VAS score, respectively, in all subjects. Results: Overall, treatment with pregabalin resulted in a significantly lower LEP N2-P2 PtP amplitude vs placebo (-3.30 µV, P < 0.0001). There were no clinically relevant differences in N2-P2 PtP amplitudes between placebo and either ASP9226 dose (-0.31 µV and -0.27 µV). Furthermore, subjects reported significantly lower VAS pain scores with pregabalin vs placebo (-9.90%, P < 0.0001) in contrast to ASP9226 30 mg (-2.1%) and ASP9226 50 mg (1.2%) vs placebo. Subgroup analysis of LEP and VAS pain in participants with positive prestudy capsaicin response (n = 13) were in keeping with results in all subjects. Conclusions: ASP9226 was well tolerated; however, there was no improvement in LEP and VAS pain scores with ASP9226 at either dose vs placebo.

Structure and variation of CRISPR and CRISPR-flanking regions in deleted-direct repeat region Mycobacterium tuberculosis complex strains.

BACKGROUND: CRISPR and CRISPR-flanking genomic regions are important for molecular epidemiology of Mycobacterium tuberculosis complex (MTBC) strains, and potentially for adaptive immunity to phage and plasmid DNA, and endogenous roles in the bacterium. Genotyping in the Israel National Mycobacterium Reference Center Tel-Aviv of over 1500 MTBC strains from 2008-2013 showed three strains with validated negative 43-spacer spoligotypes, that is, with putatively deleted direct repeat regions (deleted-DR/CRISPR regions). Two isolates of each of three negative spoligotype MTBC (a total of 6 isolates) were subjected to Next Generation Sequencing (NGS). As positive controls, NGS was performed for three intact-DR isolates belonging to T3_Eth, the largest multiple-drug-resistant (MDR)-containing African-origin cluster in Israel. Other controls consisted of NGS reads and complete whole genome sequences from GenBank for 20 intact-DR MTBC and for 1 deleted-DR MTBC strain recognized as CAS by its defining RD deletion. RESULTS: NGS reads from negative spoligotype MTBC mapped to reference H37Rv NC_000962.3 suggested that the DR/CRISPR regions were completely deleted except for retention of the middle IS6110 mobile element. Clonally specific deletion of CRISPR-flanking genes also was observed, including deletion of at least cas2 and cas1 genes. Genomic RD deletions defined lineages corresponding to the major spoligotype families Beijing, EAI, and Haarlem, consistent with 24 loci MIRU-VNTR profiles. Analysis of NGS reads, and analysis of contigs obtained by manual PCR confirmed that all 43 gold standard DR/CRISPR spacers were missing in the deleted-DR genomes. CONCLUSIONS: Although many negative spoligotype strains are recorded as spoligotype-international-type (SIT) 2669 in the SITVIT international database, this is the first time to our knowledge that it has been shown that negative spoligotype strains are found in at least 4 different 24 loci MIRU-VNTR and RD deletion families. We report for the first time negative spoligotype-associated total loss of CRISPR region spacers and repeats, with accompanying clonally specific loss of flanking genes, including at least CRISPR-associated genes cas2 and cas1. Since cas1 deleted E.coli shows increased sensitivity to DNA damage and impaired chromosomal segregation, we discussed the possibility of a similar phenotype in the deleted-DR strains and Beijing family strains as both lack the cas1 gene.

Night shift work at specific age ranges and chronic disease risk factors.

OBJECTIVES: We examined the association of night shift work history and age when night shift work was performed with cancer and cardiovascular disease risk factors among 54 724 women in the Nurses' Health Study (NHS) II. METHODS: We calculated age-adjusted and socioeconomic status-adjusted means and percentages for cancer and cardiovascular risk factors in 2009 across categories of night shift work history. We used multivariable-adjusted logistic regression to estimate odds ratios (ORs) and 95% CIs for key risk factors among 54 724 participants (72% ever shift workers). We further examined these associations by age (20-25, 26-35, 36-45 and 46+ years) at which shift work was performed. RESULTS: Ever night shift workers had increased odds of obesity (body mass index ≥30 kg/m(2); OR=1.37, 95% CI 1.31 to 1.43); higher caffeine intake (≥131 mg/day; OR=1.16, 95% CI 1.12 to 1.22) and total calorie intake (≥1715 kcal/day; OR=1.09, 95% CI 1.04 to 1.13); current smoking (OR=1.30, 95% CI 1.19 to 1.42); and shorter sleep durations (≤7 h of sleep/day; OR=1.19, 95% CI 1.15 to 1.24) compared to never night shift workers. These estimates varied depending on age at which night work was performed, with a suggestion that night shift work before age 25 was associated with fewer risk factors compared to night shift work at older ages. CONCLUSIONS: Our results indicate that night shift work may contribute to an adverse chronic disease risk profile, and that risk factors may vary depending on the age at which night shift work was performed.

The association of body size in early to mid-life with adult urinary 6-sulfatoxymelatonin levels among night shift health care workers.

BACKGROUND: Adult body mass index (BMI) has been associated with urinary melatonin levels in humans; however, whether earlier-life body size is associated with melatonin, particularly among night shift workers, remains unknown. METHODS: We evaluated associations of birth weight, body shape (or somatotype) at ages 5 and 10, BMI at age 18 and adulthood, weight change since age 18, waist circumference, waist to hip ratio, and height with creatinine-adjusted morning urinary melatonin (6-sulfatoxymelatonin, aMT6s) levels among 1,343 healthy women (aged 32-53 at urine collection, 1996-1999) in the Nurses' Health Study (NHS) II cohort. Using multivariable linear regression, we computed least-square mean aMT6s levels across categories of body size, and evaluated whether these associations were modified by night shift work. RESULTS: Adult BMI was inversely associated with aMT6s levels (mean aMT6s levels = 34 vs. 50 ng/mg creatinine, comparing adult BMI ≥ 30 vs. <20 kg/m(2); P trend < 0.0001); however, other measures of body size were not related to aMT6s levels after accounting for adult BMI. Night shifts worked prior to urine collection, whether recent or cumulatively over time, did not modify the association between adult BMI and aMT6s levels (e.g., P interaction = 0.72 for night shifts worked within two weeks of urine collection). CONCLUSIONS: Our results suggest that adult BMI, but not earlier measures of body size, is associated with urinary aMT6s levels in adulthood. These observations did not vary by night shift work status, and suggest that adult BMI may be an important mechanism by which melatonin levels are altered and subsequently influence chronic disease risk.

A pilot study investigating the effects of remote ischemic preconditioning in high-risk cardiac surgery using a randomised controlled double-blind protocol.

The efficacy of remote ischemic preconditioning (RIPC) in high-risk cardiac surgery is uncertain. In this study, 96 adults undergoing high-risk cardiac surgery were randomised to RIPC (3 cycles of 5 min of upper-limb ischemia induced by inflating a blood pressure cuff to 200 mmHg with 5 min of reperfusion) or control. Main endpoints were plasma high-sensitivity troponin T (hsTNT) levels at 6 and 12 h, worst post-operative acute kidney injury (AKI) based on RIFLE criteria, and noradrenaline duration. hsTNT levels were log-normally distributed and higher with RIPC than control at 6-h post cross-clamp removal [810 ng/ml (IQR 527-1,724) vs. 634 ng/ml (429-1,012); ratio of means 1.41 (99.17% CI 0.92-2.17); P=0.04] and 12 h [742 ng/ml (IQR 427-1,700) vs. 514 ng/ml (IQR 356-833); ratio of means 1.56 (99.17% CI 0.97-2.53); P=0.01]. After adjustment for baseline confounders, the ratio of means of hsTNT at 6 h was 1.23 (99.17% CI 0.88-1.72; P=0.10) and at 12 h was 1.30 (99.17% CI 0.92-1.84; P=0.05). In the RIPC group, 35/48 (72.9%) had no AKI, 5/48 (10.4%) had AKI risk, and 8/48 (16.7%) had either renal injury or failure compared to the control group where 34/48 (70.8%) had no AKI, 7/48 (14.6%) had AKI risk, and 7/48 (14.6%) had renal injury or failure (Chi-squared 0.41; two degrees of freedom; P = 0.82). RIPC increased post-operative duration of noradrenaline support [21 h (IQR 7-45) vs. 9 h (IQR 3-19); ratio of means 1.70 (99.17% CI 0.86-3.34); P=0.04]. RIPC does not reduce hsTNT, AKI, or ICU-support requirements in high-risk cardiac surgery.

Lessening Organ Dysfunction With Vitamin C (LOVIT) Trial: Statistical Analysis Plan.

BACKGROUND: The LOVIT (Lessening Organ Dysfunction with Vitamin C) trial is a blinded multicenter randomized clinical trial comparing high-dose intravenous vitamin C to placebo in patients admitted to the intensive care unit with proven or suspected infection as the main diagnosis and receiving a vasopressor. OBJECTIVE: We aim to describe a prespecified statistical analysis plan (SAP) for the LOVIT trial prior to unblinding and locking of the trial database. METHODS: The SAP was designed by the LOVIT principal investigators and statisticians, and approved by the steering committee and coinvestigators. The SAP defines the primary and secondary outcomes, and describes the planned primary, secondary, and subgroup analyses. RESULTS: The SAP includes a draft participant flow diagram, tables, and planned figures. The primary outcome is a composite of mortality and persistent organ dysfunction (receipt of mechanical ventilation, vasopressors, or new renal replacement therapy) at 28 days, where day 1 is the day of randomization. All analyses will use a frequentist statistical framework. The analysis of the primary outcome will estimate the risk ratio and 95% CI in a generalized linear mixed model with binomial distribution and log link, with site as a random effect. We will perform a secondary analysis adjusting for prespecified baseline clinical variables. Subgroup analyses will include age, sex, frailty, severity of illness, Sepsis-3 definition of septic shock, baseline ascorbic acid level, and COVID-19 status. CONCLUSIONS: We have developed an SAP for the LOVIT trial and will adhere to it in the analysis phase. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/36261.

The carbon monoxide donor, CORM-2, is an antagonist of ATP-gated, human P2X4 receptors.

Carbon monoxide (CO) is produced endogenously by heme oxygenase (HO) enzymes. HO-1 is highly expressed in many inflammatory disease states, where it is broadly protective. The protective effects of HO-1 expression can be largely mimicked by the exogenous application of CO and CO-releasing molecules (CORMs). Despite a dearth of pharmacological tools for their study, molecular methodologies have identified P2X4 receptors as a potential anti-nociceptive drug target. P2X4 receptors are up-regulated in animal models of inflammatory pain, and their knock-down reduces pain behaviours. In these same animal models, HO-1 expression is anti-nociceptive, and we therefore investigated whether P2X4 was a target for CO and tricarbonyldichlororuthenium (II) dimer (CORM-2). Using conventional whole-cell and perforated-patch recordings of heterologously expressed human P2X4 receptors, we demonstrate that CORM-2, but not CO gas, is an inhibitor of these channels. We also investigated the role of soluble guanylate cyclase and mitochondria-derived reactive oxygen species using pharmacological inhibitors but found that they were largely unable to affect the ability of CORM-2 to inhibit P2X4 currents. A control breakdown product of CORM-2 was also without effect on P2X4. These results suggest that P2X4 receptors are not a molecular target of endogenous CO production and are, therefore, unlikely to be mediating the anti-nociceptive effects of HO-1 expression in inflammatory pain models. However, these results show that CORM-2 is an effective antagonist at human P2X4 receptors and represents a useful pharmacological tool for the study of these receptors given the current dearth of antagonists.

Pituitary hyperplasia with Sertoli cell-only and 47,XYY syndromes: an uncommon triad.

We report the case history of a 32-year-old man with no phenotypical abnormalities who presented with infertility. Semen analysis revealed azoospermia and testicular biopsy confirmed Sertoli cell-only (SCO) syndrome. Karyotyping revealed 47,XYY and pituitary hyperplasia was found on MRI pituitary. In our patient, 47,XYY karyotype is likely to have given rise to SCO syndrome that in turn resulted in pituitary hyperplasia. The patient was evaluated by various members of the multidisciplinary team including the pituitary surgeon, endocrinologist and andrologist. The patient's partner successfully delivered a healthy baby via in vitro fertilisation with donor sperm. This triad of diagnoses (SCO syndrome, 47,XYY karyotype and pituitary hyperplasia) has not been reported previously. SCO syndrome should be considered in the presence of azoospermia, elevated follicle-stimulating hormone, low inhibin-B and normal testosterone levels. Our case report also highlights the importance of excluding genetic causes of infertility even when the patient has no phenotypical abnormalities.

Comparison of the pharmacokinetics of venlafaxine extended release and desvenlafaxine in extensive and poor cytochrome P450 2D6 metabolizers.

BACKGROUND: The goal of this study was to evaluate the impact of cytochrome P450 2D6 extensive metabolizer (EM) or poor metabolizer (PM) status on the pharmacokinetics of single doses of venlafaxine extended release (ER) and desvenlafaxine (administered as desvenlafaxine succinate) in healthy adults. METHODS: In an open-label, crossover study, 14 healthy volunteers (aged 18-55 years; 7 EMs and 7 PMs) received, in randomized sequence, single doses of venlafaxine ER 75 mg/d or desvenlafaxine 100 mg/d. Cytochrome P450 2D6 genotyping was performed, and plasma drug levels were measured. The arithmetic means and standard deviation (SD) for area under the plasma concentration-versus-time curve (AUC) and peak plasma concentration (Cmax) were calculated. Comparisons of AUC and Cmax between cytochrome P450 2D6 EMs and PMs were calculated using a Wilcoxon exact test. RESULTS: After administration of venlafaxine ER, mean Cmax and AUC of venlafaxine were significantly greater in PMs compared with EMs, whereas mean Cmax and AUC of its metabolite, desvenlafaxine, were significantly lower for PMs than for EMs (P = 0.001, all comparisons). In contrast, mean Cmax and AUC of desvenlafaxine after administration of desvenlafaxine were comparable between EMs and PMs. CONCLUSIONS: Cytochrome P450 2D6 genetic polymorphisms had no discernible impact on exposure to desvenlafaxine after desvenlafaxine administration; in contrast, compared with an EM phenotype, a PM phenotype had a significant effect on venlafaxine and desvenlafaxine plasma concentrations after venlafaxine ER administration. This reduced pharmacokinetic variability of desvenlafaxine may translate into better uniformity of response for patients receiving desvenlafaxine versus venlafaxine, but additional studies are required to test this hypothesis.

The effects of desvenlafaxine and paroxetine on the pharmacokinetics of the cytochrome P450 2D6 substrate desipramine in healthy adults.

The potential for cytochrome P450 (CYP) 2D6 substrates to interact with desvenlafaxine (administered as desvenlafaxine succinate) and paroxetine was evaluated. In an open-label, crossover study, 20 healthy volunteers (aged 21-50) were randomized to 2 series of 9 days each of desvenlafaxine (100 mg/d) or paroxetine (20 mg/d), separated by a 5-day washout. The CYP2D6 substrate desipramine (50 mg) was administered alone on day 1 and coadministered on day 6 of dosing with either desvenlafaxine or paroxetine. CYP2D6 genotype was determined at baseline. Based on least squares geometric mean ratios between reference (desipramine alone) and test treatments, desvenlafaxine produced minor increases in desipramine area under the plasma concentration versus time curve (AUC; 36%) and peak plasma concentration (C(max); 30%) (vs paroxetine: 419%, 90%, respectively; both P < .001). Desvenlafaxine produced little change in 2-hydroxydesipramine AUC (16% increase) and C(max) (0%) versus paroxetine (18% and 82% decreases, respectively; P = .008, P < .001, respectively), indicating that desvenlafaxine, especially at the recommended therapeutic dose of 50 mg/d for major depressive disorder in the United States, has little potential to interact with CYP2D6 substrates.

Acute hot foot: Charcot neuroarthropathy or osteomyelitis? Untangling a diagnostic web.

A 55-year-old man with poorly controlled type 1 diabetes with microvascular and macrovascular complications presented with a 1-week history of painful erythematous swelling on the dorsum of the left foot with two areas of foot ulceration. Inflammatory markers were raised. MRI of the left foot revealed a soft tissue swelling on the dorsum of the left foot, marrow oedema and destruction of several small joints of the foot, indicating osteomyelitis and Charcot neuroarthropathy (CN). The soft tissue swelling on the dorsum of the left foot was debrided; per-operatively bone destruction of base of the fifth metatarsal was found. The patient received intravenous antibiotics for 6 weeks. The clinical features of CN including erythema, oedema and elevated temperature of the left foot settled with off-loading the foot in an air cast walker after 6 months. Our case highlights the need to recognise CN in an acutely inflamed foot of diabetic patients with neuropathy, even when other conditions like soft tissue infection and osteomyelitis can explain the clinical features.

An assessment of drug-drug interactions: the effect of desvenlafaxine and duloxetine on the pharmacokinetics of the CYP2D6 probe desipramine in healthy subjects.

A number of antidepressants inhibit the activity of the cytochrome P450 2D6 enzyme system, which can lead to drug-drug interactions. Based on its metabolic profile, desvenlafaxine, administered as desvenlafaxine succinate, a new serotonin-norepinephrine reuptake inhibitor, is not expected to have an impact on activity of CYP2D6. This single-center, randomized, open-label, four-period, crossover study was undertaken to evaluate the effect of multiple doses of desvenlafaxine (100 mg/day, twice the recommended therapeutic dose for major depressive disorder in the United States) and duloxetine (30 mg b.i.d.) on the pharmacokinetics (PK) of a single dose of desipramine (50 mg). A single dose of desipramine was given first to assess its PK. Desvenlafaxine or duloxetine was then administered, in a crossover design, so that steady-state levels were achieved; a single dose of desipramine was then coadministered. The geometric least-square mean ratios (coadministration versus desipramine alone) for area under the plasma concentration versus time curve (AUC) and peak plasma concentrations (C(max)) of desipramine and 2-hydroxydesipramine were compared using analysis of variance. Relative to desipramine alone, increases in AUC and C(max) of desipramine associated with duloxetine administration (122 and 63%, respectively) were significantly greater than those associated with desvenlafaxine (22 and 19%, respectively; P < 0.001). Duloxetine coadministered with desipramine was also associated with a decrease in 2-hydroxydesipramine C(max) that was significant compared with the small increase seen with desvenlafaxine and desipramine (-24 versus 9%; P < 0.001); the difference between changes in 2-hydroxydesipramine AUC did not reach statistical significance (P = 0.054). Overall, desvenlafaxine had a minimal impact on the PK of desipramine compared with duloxetine, suggesting a lower risk for CYP2D6-mediated drug interactions.

Single-dose pharmacokinetics of oral and intravenous pantoprazole in children and adolescents.

The primary objective was to determine the pharmacokinetics of single oral and intravenous doses of pantoprazole in children 2 to 16 years of age. The secondary objective was to assess the safety and tolerability of these doses. Male and female hospitalized and nonhospitalized patients from ages 5 to 16 years received single oral doses (20 mg or 40 mg), and those from ages 2 to 16 years received single intravenous doses (0.8 mg/kg or 1.6 mg/kg) of pantoprazole. The plasma concentration-time data for each patient were analyzed using noncompartmental methods. Routine safety and tolerability assessments were also obtained. The mean values for peak plasma concentration and total area under the plasma concentration-time curve increased with increasing dose. Pharmacokinetic values were similar in patients from ages 2 to 16 years and to those previously obtained in adults. Statistically significant differences were observed for dose-normalized pantoprazole area under the plasma concentration-time curve when compared between CYP2C19 extensive metabolizers with 1 versus 2 functional alleles. All adverse events were mild in severity and considered to be unrelated to study drug. The pharmacokinetic profile of oral and intravenous pantoprazole was similar in children ages 2 to 16 years. The doses used here were safe and well tolerated in this population.

Impact of CYP2D6 on venlafaxine metabolism in Trinidadian patients with major depressive disorder.

AIM: This study aimed to assess the impact of CYP2D6 and CYP2C19 variation on venlafaxine (VEN) at steady state in patients from Trinidad and Tobago of Indian and African descent with major depressive disorder. PATIENTS & METHODS: Patients were phenotyped with dextromethorphan, genotyped for CYP2D6 and CYP2C19, and metabolic ratios for VEN obtained at 2-week intervals. RESULTS: Of 61 patients, 55 were genotyped and phenotyped and 47 completed 8 weeks of VEN treatment. The majority of patients had metabolic ratios for VEN that were consistent with those for dextromethorphan and genotype-predicted phenotype using activity scores. One subject presented with a novel no-function allele, CYP2D6*99. No correlations were observed with CYP2C19 genotype. CONCLUSION: CYP2D6 genotype analysis provides valuable information to individualize drug therapy with VEN.

Biomarkers for drug development in early psychosis: Current issues and promising directions.

A major goal of current research in schizophrenia is to understand the biology underlying onset and early progression and to develop interventions that modify these processes. Biomarkers can play a critical role in identifying disease state, factors contributing to underlying progression, as well as predicting and monitoring response to treatment. Once biomarker-based therapeutics are established, biomarkers can guide treatment selection. It is increasingly clear that a wide range of potential biomarkers should be examined in schizophrenia, given the large number of genetic and environmental factors that have been identified as risk factors. New models for analysis of biomarkers are needed that represent the central nervous system as a highly complex, dynamic, and interactive system. Many tools are available with which to study relevant brain chemistry, but most are indirect measures and represent only a small fraction of the potential etiologic factors contributing to the molecular, structural and functional components of schizophrenia. This review represents the work of the International Society for CNS Clinical Trials and Methodology (ISCTM) Biomarkers Working Group. It discusses advantages and disadvantages of different categories of biomarkers and provides a summary of evidence that biomarkers representing inflammation, oxidative stress, endocannabinoids, glucocorticoid, and biogenic amines systems are dysregulated and potentially interactive in early phase schizophrenia. As has been recently demonstrated in several neurodevelopmental and neurodegenerative disorders, a multi-modal, longitudinal strategy involving a diverse array of biomarkers and new approaches to statistical modeling are needed to improve early interventions based on the fuller understanding.

Renoprotection by remote ischemic conditioning during elective coronary revascularization: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Remote ischemic conditioning (RIC) has been recognized an emerging non-invasive approach for preventing acute kidney injury (AKI) in patients undergoing either elective coronary artery bypass graft (CABG) surgery or percutaneous coronary intervention (PCI). On the other hand, accumulating evidence has indicated the involving role of pre-CABG contrast usage for coronary angiography in post-surgery AKI risk. Along with the shortening time delay of CABG after coronary angiography, and the prevalent hybrid coronary revascularization (HCR), the AKI prevention by RIC has faced challenges following coronary revascuralization. METHODS: Randomized controlled trials (RCTs) were searched from Pubmed, EMBase, and Cochrane library (until May 2016). The primary outcome was postoperative AKI. The second outcomes were included the requirement for renal replacement therapy (RRT), and in-hospital or 30-day mortality. RESULTS: Twenty eligible RCTs (CABG, 3357 patients; PCI, 1501 patients) were selected. RIC significantly halved the incidence of AKI following PCI when compared with controls [n=1501; odds ratio (OR)=0.51; 95% CI, 0.32 to 0.82; P=0.006; I(2)=29.6%]. However, RIC did not affect the incidence of AKI following CABG (n=1850; OR=0.94; 95% CI, 0.73 to 1.19; P=0.586; I(2)=12.4%). The requirement for RRT and in-hospital mortality was not affected by RIC in CABG (n=2049, OR=1.04, P=0.87; n=1920, OR=0.89, P=0.7; respectively). CONCLUSIONS: Our meta-analysis suggests that RIC for preventing AKI following CABG has faced with challenges in terms of AKI, the requirement for RRT, and mortality. However, RIC shows a renoprotective benefit for PCI. Hence, our findings may infer the preserved renal effects of RIC in CABG with preconditioning before the coronary angiography, or in HCR.

Effects of age and sex on the disposition of retigabine.

BACKGROUND: The novel antiepileptic drug retigabine is the first selective M-current potassium channel opener for KCNQ2/3 and KCNQ3/5 channels. Retigabine undergoes phase II metabolism (N-glucuronidation, acetylation) exclusively and renal excretion. OBJECTIVE: Our objective was to evaluate the effects of age and sex on the pharmacokinetics of retigabine. METHODS: Healthy young (age range, 18-40 years) and elderly (age range, 66-81 years) white subjects (12 men and 12 women in each group) received a single 200-mg oral dose of retigabine. After dosing, blood was collected over a 72-hour period to determine plasma concentrations of retigabine and its acetylated metabolite, AWD21-360. Pharmacokinetics was compared for age group and sex by ANOVA. RESULTS: In young men, retigabine was rapidly absorbed, with the maximum concentration occurring within 2 hours, and was eliminated with an apparent clearance of 0.67 L x h(-1) x kg(-1) and a mean terminal half-life of 8.5 hours. Subjects were similarly exposed to AWD21-360. Compared with young men, young women had higher retigabine maximum concentration (56%) and exposure (20%) but similar clearance (0.68 L x h(-1) x kg(-1)); these differences were related to differences in body weight. Although maximum concentration was similar in elderly subjects, retigabine elimination was slower (30% lower apparent clearance normalized for weight), resulting in higher exposure (42%) and a longer half-life (30%). Because phase II metabolism is scarcely affected by age, these differences may be related to the known decline of renal function with age. CONCLUSIONS: Although there are no substantial sex-related differences in the disposition of retigabine, a relevant decrease in clearance resulting in higher exposure occurs in elderly patients. The results suggest that decline of renal function with age may account for some of the observed changes.

Multiple-dose, linear, dose-proportional pharmacokinetics of retigabine in healthy volunteers.

Retigabine, a first-in-class selective M-current potassium channel opener, is a novel antiepileptic compound currently in clinical development. The purpose of this randomized placebo-controlled study was to assess retigabine oral safety and pharmacokinetics in healthy male volunteers (N = 45). Subjects received one dose on day 1 and doses every 12 hours for the next 14 days. Fixed doses were given to the first four groups (200, 400, 500, and 600 mg per day). Titrated doses were given to group 5 in 100 mg increases every 4 days, achieving 700 mg per day on day 15. Serial blood samples were collected on days 1 and 15. Pharmacokinetic parameters were compared between days and among dose groups. After administration of a single dose, retigabine was rapidly absorbed, with maximum concentrations of 387 ng/ml (normalized to a 100 mg dose) occurring within 1.5 hours. Retigabine was eliminated with a mean terminal half-life of 8.0 hours and an apparent oral clearance of 0.70 L/h/kg in white subjects. In black subjects, retigabine clearance and volume of distribution were 25% and 30% lower, respectively, after normalizing by body weight, leading to higher exposure in this population. Retigabine's pharmocokinetics was linearly dose proportional. Steady-state pharmacokinetics was in agreement with single-dose pharmacokinetics, and the accumulation ratio was about 1.5. Retigabine and AWD21-360 trough evening concentrations were significantly lower (about 30% to 35%) than morning values. The titration regimen allowed for higher doses to be tolerated compared to the fixed-dose regimen. In conclusion, the pharmacokinetics of retigabine is linearly dose proportional for daily doses of 100 to 700 mg and is not modified on multiple administrations.