Pharmacological characterization of the selective orexin-1 receptor antagonist JNJ-61393215 in healthy volunteers.

BACKGROUND: Up to 40% of patients suffering from anxiety disorders do not benefit from currently available pharmacological treatments. Overactivity of the orexin-1 receptor (OX1R) has been implicated in anxiety- and panic-related states. AIM & METHODS: We investigated the pharmacokinetics and characterized the pharmacodynamic (PD) profile of the OX1R antagonist JNJ-61393215 using a battery of central nervous system assessments investigating relevant functional domains such as alertness, attention, (visuo)motor coordination, balance, subjective effects and resting-state electroencephalography in a single ascending dose placebo-controlled study in doses from 1 to 90 mg inclusive, assessing PD up to 10 h after dosing, safety and pharmacokinetic in 48 healthy male subjects. RESULTS: Average time to maximal plasma concentration (Tmax) ranged between 1.0 and 2.25 h; average half-life ranged from 13.6 to 24.6 h and average maximum plasma concentration ranged from 1.4 to 136.8 ng/mL in the 1 and 90 mg groups, respectively. JNJ-61393215 did not demonstrate any statistically significant or clinically meaningful effects on any PD endpoint at any dose investigated at Tmax nor over the total period up to 10 h post-dose and was well tolerated. The reported somnolence rate was 16.7% (which was attributable to the cohorts receiving 6 mg and higher doses) compared to 12.5% in placebo. CONCLUSION: This observation is in line with our knowledge about the OX1R in preclinical studies, where only inconsistent and non-dose-dependent changes in electroencephalography or other behavioural measures were observed under non-challenged conditions, potentially exemplifying the need for a challenged subject.

Solving the crisis in psychopharmacological research: Cellular-membrane(s) pharmacology to the rescue?

There is an urgent need for the introduction of novel and better (i.e., improved risk-benefit profile) compounds for the treatment of major psychiatric disorders, in particular mood and psychotic disorders. However, despite increased societal awareness and a rising public and professional demand for such agents from patients and physicians, the pharmaceutical industry continues to close down its psychopharmacology research facilities in reaction to the lack of success with the search for new psychotropics. It is high time to stop this untoward trend and explore "new" lines of investigation to solve the current crisis in psychopharmacological research. In line with the prevailing molecular view in drug research in general, also in psychopharmacology mechanistic explanations for drug effects are "traditionally" looked for at the level of molecular targets, like receptors and transporters. Also, more recent approaches, although using so-called systems- and function-based approaches to model the multidimensional characteristics of psychiatric disorders and psychotropic drug action, still emphasize this search strategy for new therapeutic leads by identification of single molecules or molecular pathways. This "psychomolecular gaze" overlooks and disregards the fact that psychotropic agents usually are highly hydrophobic and amphipathic/amphiphilic agents that, in addition to their interaction with membrane-bound proteins in the form of e.g. receptors or transporters, also interact strongly with the lipid component of cellular membranes. Here we suggest to develop a program of systematic, whole-cell level based, investigation into the role of these physical-chemical cellular membrane interactions in the therapeutic action of known psychotherapeutics. This complementary yet conceptually different approach, in our opinion, will complement drug development in psychopharmacology and thereby assist in overcoming the current crisis. In this way the "old" physical theory of drug action, which antedates the current, primary molecular, paradigm may offer "new" options for lead discovery in psychopharmacological research.

[Psychiatric manifestations due to abnormal glucocorticoid levels]. / Psychiatrische beelden bij afwijkende cortisolproductie.

This clinical case presentation describes the disease trajectory in two patients who presented with psychiatric symptoms as a result of abnormal serum glucocorticoid levels. One case involves a 58-year-old man with hypercortisolism, the other case concerns a 55-year-old woman with hypocortisolism. In both cases there was a considerable diagnostic delay in recognizing the underlying adrenal gland pathology. Abnormal glucocorticoid levels, caused by endocrine disorders, often results in psychiatric symptoms. Delay in diagnosis may have adverse consequences. Hyper- or hypocortisolism should be considered in patients who present with an atypical presentation of psychiatric symptoms. Moreover, the absence of specific physical signs or symptoms at first presentation in such patients does not exclude an underlying endocrinological cause. Therefore, physical and psychiatric reassessment of such patients should be considered at regular intervals.

A pharmacological tool to assess vasopressinergic co-activation of the hypothalamus-pituitary-adrenal axis more integrally in healthy volunteers.

Pharmacological function tests consisting of 100 µg hCRH (corticorelin) and 10 µg dDAVP (desmopressin) mimic endogenous hypothalamus-pituitary-adrenal (HPA) axis activation. However, physiological CRH concentrations preclude informative vasopressinergic co-activation (using dDAVP) and independent quantification of both corticotrophinergic (using hCRH) and vasopressinergic (using dDAVP) activation is limited due to administration on separate occasions. This randomized, double-blind, placebo-controlled, partial five-way crossover study in healthy males and females (six : six) examined whether (1) concomitant administration of dDAVP and hCRH provides more informative vasopressinergic co-activation than dDAVP alone; and (2) whether the administration of dDAVP followed two hours later by hCRH can quantify both vasopressinergic and corticotrophinergic activation on a single test day. Combining 10 µg dDAVP with 10 µg and 30 µg hCRH caused dose-related ACTH and cortisol release which was larger than with 10 µg dDAVP alone and respectively comparable to and greater than that induced by 100 µg hCRH. Using 10 µg dDAVP alone demonstrated limited ACTH release while the effects of 100 µg hCRH two hours later were three times as large. ACTH and cortisol released by 10 µg dDAVP returned to baseline prior to 100 µg hCRH administration and dDAVP did not influence the response to subsequent hCRH administration. Dose-related vasopressinergic co-activation of the HPA axis was induced by combining 10 µg dDAVP with 10 µg and 30 µg hCRH. Combining 10 µg dDAVP with 10 µg hCRH induced the potentially most informative vasopressinergic co-activation since it is not restricted by ceiling or flooring effects. The hCRH response was not affected by prior dDAVP, allowing for a practical function test examining both HPA activation routes on the same day.

Desmopressin as a pharmacological tool in vasopressinergic hypothalamus-pituitary-adrenal axis modulation: neuroendocrine, cardiovascular and coagulatory effects.

Arginine-vasopressin (AVP) is a physiological co-activator of the hypothalamus-pituitary-adrenal (HPA) axis, together with corticotrophin releasing hormone (CRH). A synthetic analogue of AVP, desmopressin (dDAVP), is often used as a pharmacological tool to assess co-activation in health and disease. The relation between dDAVP's neuroendocrine, cardiovascular, pro-coagulatory, anti-diuretic and non-specific stress effects has not been studied. A randomized, double-blind, placebo-controlled, three-way crossover study was performed in 12 healthy male and female volunteers (6 : 6). dDAVP was administered intravenously as a 10 µg bolus (over 1 min) or a 30 µg incremental infusion (over 60 min). Neuroendocrine, cardiovascular, pro-coagulatory, anti-diuretic effects and adverse events (AEs) were recorded, and autonomic nervous system (ANS) activation evaluated. The incremental infusion reached 1.8-fold higher dDAVP concentrations than the bolus. Neuroendocrine effects were similar for the 10 µg dDAVP bolus and the 30 µg incremental infusion, while cardiovascular and coagulatory effects were greater with the 30 µg dose. Osmolality and ANS activity remained uninfluenced. AEs corresponded to dDAVP's side-effect profile. In conclusion, the neuroendocrine effects of a 10 µg dDAVP bolus administered over 1 min are similar to those of a 30 µg incremental infusion administered over one hour, despite higher dDAVP concentrations after the infusion. Cardiovascular and coagulatory effects showed clear dose-related responses. A 10 µg dDAVP bolus is considered a safe vasopressinergic function test at which no confounding effects of systemic or autonomic stress were seen.

Metoclopramide as pharmacological tool to assess vasopressinergic co-activation of the hypothalamus-pituitary-adrenal (HPA) axis: a study in healthy volunteers.

The synthetic vasopressin (AVP) analogue desmopressin (dDAVP) has been used as pharmacological function test to quantify vasopressinergic co-activation of the hypothalamus-pituitary-adrenal (HPA) axis in the past. Such exogenous vasopressinergic stimulation may induce confounding cardiovascular, pro-coagulatory and anti-diuretic effects and low endogenous corticotrophin-releasing-hormone (CRH) levels may limit its potential to reliably assess co-activation. Alternatively, the dopamine-2-(D2)-antagonist metoclopramide is believed to induce co-activation indirectly by releasing endogenous AVP. We investigated this indirect co-activation with metoclopramide under conditions of low and enhanced endogenous CRH release in healthy volunteers. A randomized, double-blind, placebo-controlled, four-way crossover study was performed in 12 healthy males. CRH release was induced by administering an oral 5-hydroxytryptophan (5-HTP) 200 mg function test. Co-activation was investigated by administering metoclopramide 10mg intravenously around the expected maximal effect of 5-HTP. The neuroendocrine effects were compared to those of metoclopramide alone, the 5-HTP test alone and matching placebo. Metoclopramide safely induced HPA-axis activation by itself, and potently synergized 5-HTP-induced corticotrophinergic activation of the HPA axis. These findings are indicative of vasopressinergic co-activation and suggest a role for metoclopramide as a practical function test for co-activation of the HPA axis. However, its application will be hampered pending clarification of the exact pharmacological mechanism by which metoclopramide induces co-activation of the HPA axis.

Hypothalamic glutamate levels following serotonergic stimulation: a pilot study using 7-Tesla magnetic resonance spectroscopy in healthy volunteers.

INTRODUCTION AND PURPOSE: Functional proton magnetic resonance spectroscopy (MRS) can be applied to measure pharmacodynamic effects of central nervous system (CNS)-active drugs. The serotonin precursor 5-hydroxytryptophan (5-HTP), administered together with carbidopa and granisetron to improve kinetics and reduce adverse effects, acutely enhances central serotonergic neurotransmission and induces hypothalamus-pituitary-adrenal-(HPA) axis activation. We studied the hypothalamic levels of glutamate/glutamine (Glx), choline (Chol), N-acetyl-aspartate (NAA) and creatine using 7-Tesla (7T) MRS, and adrenocorticotropic hormone (ACTH) and cortisol in peripheral blood, after the administration of the 5-HTP function test in healthy volunteers. METHODS: A randomized, double blind, placebo-controlled, two-way cross-over study was performed in 12 healthy males with a 7day wash-out period. After administration of the oral 5-HTP function test, ACTH and cortisol were measured over 4h and MRS scans at 7T were performed every 30min over 3h measuring Glx:Creatine, Chol:Creatine and NAA:Creatine ratios. RESULTS: In the hypothalamus, the administration of 5-HTP had no effect on the average Glx, Chol or NAA levels over 180min but induced a significant decrease of Glx at 60min on post-hoc analysis. 5-HTP-induced significant ACTH release reaching an E(max) of 60.2ng/L at 80min followed by cortisol with an E(max) of 246.4ng/mL at 110min. CONCLUSIONS: The reduction in hypothalamic Glx levels after serotonergic stimulation is compatible with activation of excitatory neurons in this region, which is expected to cause depletion of local glutamate stores. The hypothalamic MRS-response reached its maximum prior to subsequent increases of ACTH and cortisol, which support the functional relevance of hypothalamic Glx-depletion for activation of the HPA-axis. This exploratory study shows that MRS is capable of detecting neuronal activation following functional stimulation of a targeted brain area.

Enhanced tolerability of the 5-hydroxytryptophane challenge test combined with granisetron.

A recently developed oral serotonergic challenge test consisting of 5-Hydroxytryptophane (5-HTP, 200 mg) combined with carbidopa (CBD, 100 mg + 50 mg) exhibited dose-related neuroendocrine responsiveness and predictable pharmacokinetics. However, its applicability is limited by nausea and vomiting. A randomized, double-blind, placebo-controlled, four-way crossover trial was performed in 12 healthy male volunteers. The 5-HTP/CBD-challenge was combined with two oral anti-emetics (granisetron, 2 mg or domperidone, 10 mg) to investigate its reliability when side-effects are suppressed. The neuroendocrine response (serum cortisol and prolactin), the side-effect profile [Visual Analogue Scale Nausea (VAS)] and vomiting subjects per treatment were the main outcome measures. Compared to 5-HTP/CBD/placebo, 5-HTP/CBD/ granisetron had no impact on cortisol [% change with 95% confidence interval: -7.1% (18.9; 6.5)] or prolactin levels [-9.6% (-25.1; 9.1)]; 5-HTP/CBD/domperidone increased cortisol [+13.0% (-4.2; 33.4)], and increased prolactin extensively [+336.8% (245.7; 451.9)]. Compared to placebo, VAS Nausea increased non-significantly with granisetron [+7.6 mm (-1.3; 16.5)], as opposed to domperidone [+16.2 mm (7.2; 25.2)] and 5-HTP/CBD/placebo [+14.7 mm (5.5; 23.8)]. No subjects vomited with granisetron, compared to two subjects treated with 5-HTP/CBD/placebo and five subjects with domperidone. Compared with 5-HTP/CBD/placebo, granisetron addition decreased C(max) of 5-HTP statistically significantly different (from 1483 to 1272 ng/ml) without influencing AUC(0- infinity). Addition of granisetron to the combined 5-HTP/CBD challenge suppresses nausea and vomiting without influencing the neuroendocrine response or pharmacokinetics, enhancing its clinical applicability in future psychiatric research and drug development.

Pharmacology of rising oral doses of 5-hydroxytryptophan with carbidopa.

5-hydroxytryptophan (5-HTP) is a direct 5-hydroxytryptamine (5-HT) precursor used to assess central serotonergic function. Its use has been limited by a narrow window between neuroendocrine changes and side effects, and variable kinetics related to inconsistent administration modes. By combining 5-HTP with carbidopa (CBD), increased bioavailability for brain penetration and decreased peripheral side effects would be expected, due to reduced peripheral decarboxylation of 5-HTP to 5-HT. A double-blind, placebo-controlled, single rising dose, four-way crossover trial with placebo randomisation was performed in 15 healthy male volunteers to investigate the neuroendocrine dose-response relationship at various 5-HTP levels; the tolerability and subjective effects of oral 5-HTP at 100, 200 and 300 mg combined with CBD and the pharmacokinetic properties of the 5-HTP/CBD-challenge. Dose-dependent increases in average cortisol concentrations were observed. Mean response (area-under-the-curve) over the first 4 hours (SD): 172.0 nmol/L (22.3) for placebo, 258.3 nmol/L (72.6) for 100 mg, 328.47 nmol/L (84.6) for 200 mg and 387.3 nmol/L (82.4) for 300 mg 5-HTP. Similar dose-dependent increases for prolactin were seen while adreno-corticotrophic hormone response was more variable. 5-HTP kinetics were adequately described using a one-compartment model with first-order absorption and a lag time (mean oral clearance 28 L/h interindividual coefficient of variation 31%). Nausea and vomiting occurred dose-dependently as most frequent side effects, resulting in dose-related dropout of 6.6% at 100 mg and 45.5% at 300 mg 5-HTP. Orally administered 5-HTP combined with CBD is an effective serotonergic challenge test, exhibiting dose-related plasma concentrations and neuroendocrine responsiveness. Frequent occurrence of nausea and vomiting limits the applicability of this challenge at 5-HTP doses above 100 mg.

Low back pain outcome measurement assessment in chiropractic teaching clinics: responsiveness and applicability of two functional disability questionnaires.

OBJECTIVE: The major aims were to evaluate responsiveness and clinical/research applicability of the Revised Oswestry Disability Questionnaire (ODQ) and the Dallas Pain Questionnaire (DPQ). Construct and content validity were assessed. Patient characteristics and outcomes were also documented. DESIGN: Longitudinal observational study. SETTING: College outpatient clinics. PARTICIPANTS: Six hundred sixty-three consecutive new patients accepted for treatment of low back pain (LBP) at the clinics over a 1-yr period, age 18 or older. INTERVENTIONS: Treatment of low back pain by senior interns under the supervision of staff clinicians. MAIN OUTCOME MEASURES: ODQ and DPQ administered at baseline, 2 wk, 1 month, and monthly up to 6 months. Responsiveness: mean standardized change score (delta' = mudif/sigma dif), relative efficiency ([RE = delta' ODQ/delta DPQ']2), and improvement rates (IR). Applicability: instrument completion rates. Construct validity: correlation with VAS for pain intensity. RESULTS: ODQ responsiveness was generally consistent over time (delta' = .70-.83) and negligibly better than the DPQ activities of daily living scale (RE = 1.00-1.35); most patients self-reporting improvement showed positive outcomes (IR = 97%). For large samples (n > 100): delta' = .47-.63 and IR = 81% for the DPQ work/leisure scale; delta' = .17-.40 and IR = 54% for the DPQ anxiety/depression and social dimensions. Completion rates: 65%-78% of all instruments; 81%-100% of individual scales. Construct validity: r = .44-.68 for the ODQ, DPQ activities of daily living, and DPQ work/leisure scales; r = .20-.40 for the anxiety/depression scale. CONCLUSIONS: The ODQ and the activities of daily living and work/leisure scales from the DPQ appear appropriate for monitoring LBP patients returning for care to chiropractic teaching clinics. The social and anxiety/depression dimensions of the DPQ do not appear to be responsive in this population. The latter scale may be unsuitable on the grounds of misinterpretations.

Interexaminer reliability of eight evaluative dimensions of lumbar segmental abnormality.

The interexaminer reliability of noninvasive methods of examining lumbar spinal segments is not well established. In this project the interexaminer reliability of three experienced chiropractic examiners, who evaluated 21 symptomatic and 25 asymptomatic subjects, was explored. Eight noninvasive segmental examination strategies (dimensions) were employed at each spinal segment from T11/T12 through L5/S1. Marginal to good agreement beyond chance was noted for palpatory pain over osseous structures and in paraspinal soft-tissues. Weaker and less frequently, significant concordance between examiners was noted for detection of temperature differences (greater than or equal to 1.5 degrees F) between adjacent segments and for visual inspection for segmental abnormality. Little significant agreement between examiner was found for active and passive motion palpation, muscle tension palpation and misalignment palpation. This study suggests that "subjective" findings (pain) may be among the most reliable of conservative spinal observations. Weak but significant correlations were found when positive findings for the eight dimensions at each lumbar segment were summed to form a composite joint abnormality index. When the multidimension index was developed using the four most reliable dimensions, slightly stronger correlations were found. The strongest agreement between examiners tended to be found in the lower lumbar spine.

Intra- and interobserver reliability of passive motion palpation of the lumbar spine.

Sixty student volunteers were assessed for fixation in the lumbar spine using a passive motion palpation protocol. Subjects were examined in random order by two experienced chiropractors. Every subject was evaluated twice by each examiner. Fixations were judged present or absent for each of five lumbar motion segments. Moderate test-retest agreement beyond chance was noted at L1/2, minimal reliability at L4/5, and no significant agreement within examiners was detected for mid-lumbar segments. Interexaminer agreement beyond chance was poor for all segments assessed. When segments were grouped regionally and re-evaluated, some increase in intrarater agreement was evident, especially at L4/5/S, but interrater agreement was still absent.

Diagnosis of thyroid dysfunction: applied kinesiology compared to clinical observations and laboratory tests.

Sixty-five patients presenting to three clinics were independently evaluated for thyroid dysfunction by applied kinesiology (AK), a clinical protocol, and laboratory testing. Each was rated on a scale of 1 (unquestionably hypothyroid) to 7 (unquestionably hyperthyroid). AK ratings correlated with clinical ratings (rs = .36, p less than .002) and with laboratory ratings (rs = .32, p less than .005). Correlation between clinical and laboratory ratings was .47, p less than .000. Three AK therapy localizations had a significant correlation with the laboratory diagnosis (p less than .05). Two of these (right neurovascular-left brain and left neurolymphatic-right brain) were points associated with thyroid function. The third, ventral hand on the glabella with the other on the external occipital protuberance, is associated with pituitary function. AK enhanced but did not replace clinical/laboratory diagnosis of thyroid dysfunction. Preliminary evidence indicates that there may be a significant correlation between certain AK tests and an elevated LDH in the serum.