Vascular effects of midazolam, flumazenil, and a novel imidazobenzodiazepine MP-III-058 on isolated rat aorta.

Hypotensive influences of benzodiazepines and other GABAA receptor ligands, recognized in clinical practice, seem to stem from the existence of "vascular" GABAA receptors in peripheral blood vessels, besides any mechanisms in the central and peripheral nervous systems. We aimed to further elucidate the vasodilatatory effects of ligands acting through GABAA receptors. Using immunohistochemistry, the rat aortic smooth muscle layer was found to express GABAA γ2 and α1-5 subunit proteins. To confirm the role of "vascular" GABAA receptors, we investigated the vascular effects of standard benzodiazepines, midazolam, and flumazenil, as well as the novel compound MP-III-058. Using two-electrode voltage clamp electrophysiology and radioligand binding assays, MP-III-058 was found to have modest binding but substantial functional selectivity for α5ß3γ2 over other αxß3γ2 GABAA receptors. Tissue bath assays revealed comparable vasodilatory effects of MP-III-058 and midazolam, both of which at 100 µmol/L concentrations had efficacy similar to prazosin. Flumazenil exhibited weak vasoactivity per se, but significantly prevented the relaxant effects of midazolam and MP-III-058. These studies indicate the existence of functional GABAA receptors in the rat aorta, where ligands exert vasodilatory effects by positive modulation of the benzodiazepine binding site, suggesting the potential for further quest for leads with optimized pharmacokinetic properties as prospective adjuvant vasodilators.

Integrated Care for Comprehensive Management of Patients with Osteoarthritis: Program Development and Implementation.

Treatment of symptomatic osteoarthritis (OA) is often complicated by comorbidities, which put patients at potentially higher risks following operative interventions. Management of these comorbidities is usually separate from orthopaedic care, with patients invited to return to their orthopaedic surgeon once surgical risk factors are better controlled. However, this practice can lead to disjointed care, resulting in uncertainty, mistrust, unmanaged pain, and dissatisfaction for patients. Integrated care teams provide an effective option for coordinated comprehensive nonoperative and preoperative management of patients with knee OA and medical comorbidities. The objective of this article is to summarize the process for implementation of an integrated program to manage patients with symptomatic knee OA and the initial outcomes at our institution as an example of the effects of integrated patient management in orthopaedics. At the author's institution, an integrated program was implemented, successfully addressing the unmet need for coordinated care for patients with bone and joint health problems and medical comorbidities. Patients who completed the full program experienced significant improvements in both pain and function. Potential applications for knee surgeons considering implementing integrated care models could include pre- and postoperative management programs, nonoperative management program, and programs seeking to meet key metrics such as improved readmission rates, patient satisfaction, or value-based care. For effective program implementation, careful planning with convenient referral mechanisms, leadership buy-in, and patient-centered communication protocols are required.

Distinct and shared therapeutic neural mechanisms of mindfulness-based and social support stress reduction groups in adults with autism spectrum disorder.

BACKGROUND: Mindfulness-based stress reduction (MBSR) alleviates depression and anxiety in adults with autism spectrum disorder (ASD); however, underlying therapeutic neural mechanisms and mindfulness-specific effects have yet to be elucidated. METHODS: We randomly assigned adults with ASD to MBSR or social support/education (SE). They completed questionnaires that assessed depression, anxiety, mindfulness traits, autistic traits and executive functioning abilities as well as a self-reflection functional MRI task. We used repeated-measures analysis of covariance (ANCOVA) to evaluate behavioural changes. To identify task-specific connectivity changes, we performed a generalized psychophysiological interactions (gPPI) functional connectivity (FC) analysis on regions of interest (ROIs; insula, amygdala, cingulum and prefrontal cortex [PFC]). We used Pearson correlations to explore brain-behaviour relationships. RESULTS: Our final sample included 78 adults with ASD - 39 who received MBSR and 39 who received SE. Mindfulness-based stress reduction uniquely improved executive functioning abilities and increased mindfulness traits, whereas both MBSR and SE groups showed reductions in depression, anxiety and autistic traits. Decreases specific to MBSR in insula-thalamus FC were associated with anxiety reduction and increased mindfulness traits, including the trait "nonjudgment;" MBSR-specific decreases in PFC-posterior cingulate connectivity correlated with improved working memory. Both groups showed decreased amygdala-sensorimotor and medial-lateral PFC connectivity, which corresponded with reduced depression. LIMITATIONS: Larger sample sizes and neuropsychological evaluations are needed to replicate and extend these findings. CONCLUSION: Together, our findings suggest that MBSR and SE are similarly efficacious for depression, anxiety and autistic traits, whereas MBSR produced additional salutary effects related to executive functioning and mindfulness traits. Findings from gPPI identified shared and distinct therapeutic neural mechanisms, implicating the default mode and salience networks. Our results mark an early step toward the development of personalized medicine for psychiatric symptoms in ASD and offer novel neural targets for future neurostimulation research. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT04017793.

High amount of lecithin facilitates oral delivery of a poorly soluble pyrazoloquinolinone ligand formulated in lipid nanoparticles: Physicochemical, structural and pharmacokinetic performances.

Preclinical development of deuterated pyrazoloquinolinone ligands, promising drug candidates for various neuropsychiatric disorders, was hindered by unusually low solubility in water and oils. DK-I-60-3 (7-methoxy-d3-2-(4-methoxy-d3-phenyl)-2,5-dihydro-3Hpyrazolo[4,3-c]quinolin-3-one) is one of such pyrazoloquinolinones, and we recently reported about increased oral bioavailability of its nanocrystal formulation (NC). Lipid nanoparticles (LNP) with a high concentration of lecithin, which enhances loading capacity of the lipid matrix, may give rise to further improvement. After preformulation studies by differential scanning calorimetry and polarized light microscopy, LNP were prepared by the hot high pressure homogenization, and characterized in terms of particle size, morphology, and encapsulation efficacy. The layered structure visible on atomic force micrographs was confirmed by nuclear magnetic resonance. Obtained formulations were desirably stable, with small particle size (<100 nm), and high encapsulation efficacy (>99 %). Lecithin was partially fluid and most probably located in the outer shell of the particle, together with DK-I-60-3. While the hydrophobic part of polysorbate 80 was completely immobilized, its hydrophilic part was free in the aqueous phase. In oral neuropharmacokinetic study in rats, an around 1.5-fold increase of area under the curve with LNP compared to NC was noticed both in brain and plasma. In bioavailability study, F value of LNP (34.7 ± 12.4 %) was 1.4-fold higher than of NC (24.5 ± 7.8 %); however, this difference did not reach statistical significance. Therefore, employment of LNP platform in preclinical formulation of DK-I-60-3 imparted an incremental improvement of its physicochemical as well as pharmacokinetic behavior.

Zebrafish drug screening identifies candidate therapies for neuroprotection after spontaneous intracerebral haemorrhage.

Despite the global health burden, treatment of spontaneous intracerebral haemorrhage (ICH) is largely supportive, and translation of specific medical therapies has not been successful. Zebrafish larvae offer a unique platform for drug screening to rapidly identify neuroprotective compounds following ICH. We applied the Spectrum Collection library compounds to zebrafish larvae acutely after ICH to screen for decreased brain cell death and identified 150 successful drugs. Candidates were then evaluated for possible indications with other cardiovascular diseases. Six compounds were identified, including two angiotensin-converting enzyme inhibitors (ACE-Is). Ramipril and quinapril were further assessed to confirm a significant 55% reduction in brain cell death. Proteomic analysis revealed potential mechanisms of neuroprotection. Using the INTERACT2 clinical trial dataset, we demonstrated a significant reduction in the adjusted odds of an unfavourable shift in the modified Rankin scale at 90 days for patients receiving an ACE-I after ICH (versus no ACE-I; odds ratio, 0.80; 95% confidence interval, 0.68-0.95; P=0.009). The zebrafish larval model of spontaneous ICH can be used as a reliable drug screening platform and has identified therapeutics that may offer neuroprotection. This article has an associated First Person interview with the first author of the paper.

The imidazodiazepine, KRM-II-81: An example of a newly emerging generation of GABAkines for neurological and psychiatric disorders.

GABAkines, or positive allosteric modulators of γ-aminobutyric acid-A (GABAA) receptors, are used for the treatment of anxiety, epilepsy, sleep, and other disorders. The search for improved GABAkines, with reduced safety liabilities (e.g., dependence) or side-effect profiles (e.g., sedation) constituted multiple discovery and development campaigns that involved a multitude of strategies over the past century. Due to the general lack of success in the development of new GABAkines, there had been a decades-long draught in bringing new GABAkines to market. Recently, however, there has been a resurgence of efforts to bring GABAkines to patients, the FDA approval of the neuroactive steroid brexanolone for post-partum depression in 2019 being the first. Other neuroactive steroids are in various stages of clinical development (ganaxolone, zuranolone, LYT-300, Sage-324, PRAX 114, and ETX-155). These GABAkines and non-steroid compounds (GRX-917, a TSPO binding site ligand), darigabat (CVL-865), an α2/3/5-preferring GABAkine, SAN711, an α3-preferring GABAkine, and the α2/3-preferring GABAkine, KRM-II-81, bring new therapeutic promise to this highly utilized medicinal target in neurology and psychiatry. Herein, we also discuss possible conditions that have enabled the transition to a new age of GABAkines. We highlight the pharmacology of KRM-II-81 that has the most preclinical data reported. KRM-II-81 is the lead compound in a new series of orally bioavailable imidazodiazepines entering IND-enabling safety studies. KRM-II-81 has a preclinical profile predicting efficacy against pharmacoresistant epilepsies, traumatic brain injury, and neuropathic pain. KRM-II-81 also produces anxiolytic- and antidepressant-like effects in rodent models. Other key features of the pharmacology of this compound are its low sedation rate, lack of tolerance development, and the ability to prevent the development of seizure sensitization.

A Hyperosmolar Saline Solution Fortified with Anti-Inflammatory Components Mitigates Articular Cartilage Pro-Inflammatory and Degradative Responses in an In Vitro Model of Knee Arthroscopy.

OBJECTIVE: To evaluate differences in pro-inflammatory and degradative mediator production from osteoarthritic knee articular cartilage explants treated with a hyperosmolar saline solution supplemented with anti-inflammatory components (l-glutamine, ascorbic acid, sodium pyruvate, epigallocatechin gallate [EGCG], and dexamethasone) or normal saline using an in vitro model for knee arthroscopy. DESIGN: Full-thickness 6 mm articular cartilage explants (n = 12/patient) were created from femoral condyle and tibial plateau samples collected from patients who received knee arthroplasty. One explant half was treated for 3 hours with hyperosmolar saline (600 mOsm/L) supplemented with anti-inflammatory components and the corresponding half with normal saline (308 mOsm/L). Explants were cultured for 3 days and then collected for biomarker analyses. Media biomarker concentrations were normalized to the wet weight of the tissue (mg) and were analyzed by a paired t test with significance set at P < 0.05. RESULTS: Cartilage was collected from 9 females and 2 males (mean age = 68 years). Concentrations of MCP-1 (P < 0.001), IL-8 (P = 0.03), GRO-α (P = 0.02), MMP-1 (P < 0.001), MMP-2 (P < 0.001), and MMP-3 (P < 0.001) were significantly lower in explant halves treated with the enhanced hyperosmolar solution. When considering only those cartilage explants in the top tercile of tissue metabolism, IL-6 (P = 0.005), IL-8 (P = 0.0001), MCP-1 (P < 0.001), GRO-α (P = 0.0003), MMP-1 (P < 0.001), MMP-2 (P < 0.001), MMP-3 (P < 0.001), and GAG expression (P = 0.0001) was significantly lower in cartilage explant halves treated with the enhanced hyperosmolar solution. CONCLUSIONS: Treatment of cartilage explants with a hyperosmolar saline arthroscopic irrigation solution supplemented with anti-inflammatory components was associated with significant decreases in inflammatory and degradative mediator production and mitigation of proteoglycan loss.

Zinc Status Alters Alzheimer's Disease Progression through NLRP3-Dependent Inflammation.

Alzheimer's disease is a devastating neurodegenerative disease with a dramatically increasing prevalence and no disease-modifying treatment. Inflammatory lifestyle factors increase the risk of developing Alzheimer's disease. Zinc deficiency is the most prevalent malnutrition in the world and may be a risk factor for Alzheimer's disease potentially through enhanced inflammation, although evidence for this is limited. Here we provide epidemiological evidence suggesting that zinc supplementation was associated with reduced risk and slower cognitive decline, in people with Alzheimer's disease and mild cognitive impairment. Using the APP/PS1 mouse model of Alzheimer's disease fed a control (35 mg/kg zinc) or diet deficient in zinc (3 mg/kg zinc), we determined that zinc deficiency accelerated Alzheimer's-like memory deficits without modifying amyloid ß plaque burden in the brains of male mice. The NLRP3-inflammasome complex is one of the most important regulators of inflammation, and we show here that zinc deficiency in immune cells, including microglia, potentiated NLRP3 responses to inflammatory stimuli in vitro, including amyloid oligomers, while zinc supplementation inhibited NLRP3 activation. APP/PS1 mice deficient in NLRP3 were protected against the accelerated cognitive decline with zinc deficiency. Collectively, this research suggests that zinc status is linked to inflammatory reactivity and may be modified in people to reduce the risk and slow the progression of Alzheimer's disease.SIGNIFICANCE STATEMENT Alzheimer's disease is a common condition mostly affecting the elderly. Zinc deficiency is also a global problem, especially in the elderly and also in people with Alzheimer's disease. Zinc deficiency contributes to many clinical disorders, including immune dysfunction. Inflammation is known to contribute to the risk and progression of Alzheimer's disease; thus, we hypothesized that zinc status would affect Alzheimer's disease progression. Here we show that zinc supplementation reduced the prevalence and symptomatic decline in people with Alzheimer's disease. In an animal model of Alzheimer's disease, zinc deficiency worsened cognitive decline because of an enhancement in NLRP3-driven inflammation. Overall, our data suggest that zinc status affects Alzheimer's disease progression, and that zinc supplementation could slow the rate of cognitive decline.

Non-sedating benzodiazepines cause paralysis and tissue damage in the parasitic blood fluke Schistosoma mansoni.

Parasitic flatworm infections (e.g. tapeworms and fluke worms) are treated by a limited number of drugs. In most cases, control is reliant upon praziquantel (PZQ) monotherapy. However, PZQ is ineffective against sexually immature parasites, and there have also been several concerning reports on cestode and trematode infections with poor PZQ cure-rates, emphasizing the need for alternative therapies to treat these infections. We have revisited a series of benzodiazepines given the anti-schistosomal activity of meclonazepam (MCLZ). MCLZ was discovered in the 1970's but was not brought to market due to dose-limiting sedative side effects. However, in the decades since there have been advances in our understanding of the benzodiazepine GABAA receptor sub-types that drive sedation and the development of sub-type selective, non-sedating ligands. Additionally, the sequencing of flatworm genomes reveals that parasitic trematodes and cestodes have lost GABAAR-like ligand gated anion channels, indicating that MCLZ's anti-parasitic target is distinct from the human receptors that drive sedation. Therefore, we have screened a library of classical and non-sedating 1,4-benzodiazepines against Schistosoma mansoni and identified a series of imidazobenzodiazepines that immobilize worms in vitro. One of these hits, Xhe-II-048 also disrupted the parasite tegument, resulting in extensive vacuole formation beneath the apical membrane. The hit compound series identified has a dramatically lower (~1000×) affinity for the human central benzodiazepine binding site and is a promising starting point for the development of novel anti-schistosomal benzodiazepines with minimal host side-effects.

Effect of dose and release rate of CTGF and TGFß3 on avascular meniscus healing.

Meniscus tears in the avascular region rarely functionally heal due to poor intrinsic healing capacity, frequently resulting in tear propagation, followed by meniscus deterioration. Recently, we have reported that time-controlled application of connective tissue growth factor (CTGF) and transforming tissue growth factor ß3 (TGFß3) significantly improved healing of avascular meniscus tears by inducing recruitment and step-wise fibrocartilaginous differentiation of mesenchymal stem/progenitor cells (MSCs). In this study, we investigated effects of the dose of CTGF and the release rate of TGFß3 on avascular meniscus healing in our existing explant model. Our hypothesis was that dose and release rate of CTGF and TGFß3 are contributing factors for functional outcome in avascular meniscus healing by stem cell recruitment. Low (100 ng/ml) and high (1,000 ng/ml) doses of CTGF as well as fast (0.46 ± 0.2 ng/day) and slow (0.29 ± 0.1 ng/day) release rates of TGFß3 were applied to our established meniscus explant model for meniscus tears in the inner-third avascular region. The release rate of TGFß3 was controlled by varying compositions of poly(lactic-co-glycolic acids) (PLGA) microspheres. The meniscus explants were then cultured for 8 weeks on top of mesenchymal stem/progenitor cells (MSCs). Among the tested combinations, we found that a high CTGF dose and slow TGFß3 release are most effective for integrated healing of avascular meniscus, demonstrating improvements in alignment of collagen fibers, fibrocartilaginous matrix elaboration and mechanical properties. This study may represent an important step toward the development of a regenerative therapy to improve healing of avascular meniscus tears by stem cell recruitment. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1555-1562, 2019.

MIDD0301 - A first-in-class anti-inflammatory asthma drug targets GABAA receptors without causing systemic immune suppression.

We report a 28-day repeat dose immunotoxicity evaluation of investigational drug MIDD0301, a novel oral asthma drug candidate that targets gamma amino butyric acid type A receptors (GABAA R) in the lung. The study design employed oral administration of mice twice daily throughout the study period with 100 mg/kg MIDD0301 mixed in peanut butter. Compound dosing did not reveal signs of general toxicity as determined by animal weight, organ weight or haematology. Peanut butter plus test drug (in addition to ad libitum standard rodent chow) did not affect weight gain in the adult mice, in contrast to weight loss in 5 mg/kg prednisone-treated mice. Spleen and thymus weights were unchanged in MIDD0301-treated mice, but prednisone significantly reduced the weight of those organs over the 28-day dosing. Similarly, no differences in spleen or thymus histology were observed following MIDD0301 treatment, but prednisone treatment induced morphological changes in the spleen. The number of small intestine Peyer's patches was not affected by MIDD0301 treatment, an important factor for orally administered drugs. Circulating lymphocyte, monocyte and granulocyte numbers were unchanged in the MIDD0301-treated animals, whereas differential lymphocyte numbers were reduced in prednisone-treated animals. MIDD0301 treatment did not alter IgG antibody responses to dinitrophenyl following dinitrophenyl-keyhole limpet haemocyanin immunization, indicating that systemic humoral immune function was not affected. Taken together, these studies show that repeated daily administration of MIDD0301 is safe and not associated with adverse immunotoxicological effects in mice.

Optimization of substituted imidazobenzodiazepines as novel asthma treatments.

We describe the synthesis of analogs of XHE-III-74, a selective α4ß3γ2 GABAAR ligand, shown to relax airway smooth muscle ex vivo and reduce airway hyperresponsiveness in a murine asthma model. To improve properties of this compound as an asthma therapeutic, a series of analogs with a deuterated methoxy group in place of methoxy group at C-8 position was evaluated for isotope effects in preclinical assays; including microsomal stability, cytotoxicity, and sensorimotor impairment. The deuterated compounds were equally or more metabolically stable than the corresponding non-deuterated analogs and increased sensorimotor impairment was observed for some deuterated compounds. Thioesters were more cytotoxic in comparison to other carboxylic acid derivatives of this compound series. The most promising compound 16 identified from the in vitro screens also strongly inhibited smooth muscle constriction in ex vivo guinea pig tracheal rings. Smooth muscle relaxation, determined by reduction of airway hyperresponsiveness with a murine ovalbumin sensitized and challenged model, showed that 16 was efficacious at low methacholine concentrations. However, this effect was limited due to suboptimal pharmacokinetics of 16. Based on these findings, further analogs of XHE-III-74 will be investigated to improve in vivo metabolic stability while retaining the efficacy at lung tissues involved in asthma pathology.

Synthesis of Bisindole Alkaloids from the Apocynaceae Which Contain a Macroline or Sarpagine Unit: A Review.

Bisindole natural products consist of two monomeric indole alkaloid units as their obligate constituents. Bisindoles are more potent with respect to their biological activity than their corresponding monomeric units. In addition, the synthesis of bisindoles are far more challenging than the synthesis of monomeric indole alkaloids. Herein is reviewed the enantiospecific total and partial synthesis of bisindole alkaloids isolated primarily from the Alstonia genus of the Apocynaceae family. The monomeric units belong to the sarpagine, ajmaline, macroline, vobasine, and pleiocarpamine series. An up-to-date discussion of their isolation, characterization, biological activity as well as approaches to their partial and total synthesis by means of both synthetic and biosynthetic strategies are presented.

The Novel, Nicotinic Alpha7 Receptor Partial Agonist, BMS-933043, Improves Cognition and Sensory Processing in Preclinical Models of Schizophrenia.

The development of alpha7 nicotinic acetylcholine receptor agonists is considered a promising approach for the treatment of cognitive symptoms in schizophrenia patients. In the present studies we characterized the novel agent, (2R)-N-(6-(1H-imidazol-1-yl)-4-pyrimidinyl)-4'H-spiro[4-azabicyclo[2.2.2]octane-2,5'-[1,3]oxazol]-2'-amine (BMS-933043), in vitro and in rodent models of schizophrenia-like deficits in cognition and sensory processing. BMS-933043 showed potent binding affinity to native rat (Ki = 3.3 nM) and recombinant human alpha7 nicotinic acetylcholine receptors (Ki = 8.1 nM) and agonist activity in a calcium fluorescence assay (EC50 = 23.4 nM) and whole cell voltage clamp electrophysiology (EC50 = 0.14 micromolar (rat) and 0.29 micromolar (human)). BMS-933043 exhibited a partial agonist profile relative to acetylcholine; the relative efficacy for net charge crossing the cell membrane was 67% and 78% at rat and human alpha7 nicotinic acetylcholine receptors respectively. BMS-933043 showed no agonist or antagonist activity at other nicotinic acetylcholine receptor subtypes and was at least 300 fold weaker at binding to and antagonizing human 5-HT3A receptors (Ki = 2,451 nM; IC50 = 8,066 nM). BMS-933043 treatment i) improved 24 hour novel object recognition memory in mice (0.1-10 mg/kg, sc), ii) reversed MK-801-induced deficits in Y maze performance in mice (1-10 mg/kg, sc) and set shift performance in rats (1-10 mg/kg, po) and iii) reduced the number of trials required to complete the extradimensional shift discrimination in neonatal PCP treated rats performing the intra-dimensional/extradimensional set shifting task (0.1-3 mg/kg, po). BMS-933043 also improved auditory gating (0.56-3 mg/kg, sc) and mismatch negativity (0.03-3 mg/kg, sc) in rats treated with S(+)ketamine or neonatal phencyclidine respectively. Given this favorable preclinical profile BMS-933043 was selected for further development to support clinical evaluation in humans.

Do 25-Hydroxyvitamin D Levels Correlate With Fracture Complications?

OBJECTIVES: To determine the relationship between serum 25-hydroxyvitamin D [25(OH)D] levels and the likelihood of postoperative complications and fracture reoperation rate in orthopaedic trauma patients receiving vitamin D and calcium supplementation. DESIGN: Retrospective case series. SETTING: Level I trauma center, Midwestern United States. PATIENTS: All orthopaedic trauma patients-18 years or older-over a 20-month period were included with available initial and repeat 25(OH)D serum levels. In total, 201 patients met inclusion criteria. INTERVENTION: All patients received 1000 IU of vitamin D3 and 1500 mg of calcium daily. Vitamin D deficient and insufficient patients also received 50,000 IU of ergocalciferol (vitamin D2) weekly until 25(OH)D levels normalized or fractures healed. MAIN OUTCOME MEASUREMENTS: fracture complications and 25(OH)D levels. RESULTS: Fifteen patients experienced postoperative healing complications. There was no significant difference between initial (P = 0.92) or repeat (P = 0.91) 25(OH)D levels between patients with and without fracture healing complications. Twenty-eight patients required repeat orthopaedic surgery. There was no significant difference between initial (P = 0.62) or repeat (P = 0.18) 25(OH)D levels between patients who did or did not require repeat orthopaedic surgery. There was no significant difference between initial (P = 0.66) or repeat (P = 0.89) 25(OH)D levels between patients who did or did not require nonorthopaedic surgery. CONCLUSIONS: Serum 25(OH)D levels did not significantly affect the likelihood of fracture healing complications requiring surgery or any nonorthopaedic injury-related surgery. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Effect of dehusked Garcinia kola seeds on the overall pharmacokinetics of quinine in healthy Nigerian volunteers.

We investigated the effect of concurrent ingestion of Garcinia kola seed on the pharmacokinetics of quinine. In a randomized crossover study, 24 healthy Nigerian volunteers were assigned into 2 groups (A and B; n = 12 per group) on the basis of G. kola dose orally ingested. Each subject received 600 mg quinine sulfate before and after ingesting 12.5 g of G. kola once daily for 7 days (group A) or 12.5 g twice daily for 6 days and once on the seventh day (group B). Blood samples were collected and analyzed for plasma quinine and its metabolite (3-hydroxyquinine) using a validated high performance liquid chromatography method. Concurrent administration of quinine with G. kola reduced quinine tmax by 48% (group A), mean Cmax by 19% and 26% in groups A and B, respectively, and slight reduction in mean AUC0- ∞ of quinine in both groups. 3-hydroxyquinine Cmax also reduced by 29% and 32%; AUC0-∞ by 13% and 9%, respectively. The point estimates of the T/R ratio of the geometric means for all Cmax obtained and only the AUC0-∞ at a higher dose of G. kola were outside the 80%-125% bioequivalence range. In conclusion, an herb-drug interaction was noted with concurrent quinine and G. kola administration.

Zebrafish heart failure models for the evaluation of chemical probes and drugs.

Heart failure is a complex disease that involves genetic, environmental, and physiological factors. As a result, current medication and treatment for heart failure produces limited efficacy, and better medication is in demand. Although mammalian models exist, simple and low-cost models will be more beneficial for drug discovery and mechanistic studies of heart failure. We previously reported that aristolochic acid (AA) caused cardiac defects in zebrafish embryos that resemble heart failure. Here, we showed that cardiac troponin T and atrial natriuretic peptide were expressed at significantly higher levels in AA-treated embryos, presumably due to cardiac hypertrophy. In addition, several human heart failure drugs could moderately attenuate the AA-induced heart failure by 10%-40%, further verifying the model for drug discovery. We then developed a drug screening assay using the AA-treated zebrafish embryos and identified three compounds. Mitogen-activated protein kinase kinase inhibitor (MEK-I), an inhibitor for the MEK-1/2 known to be involved in cardiac hypertrophy and heart failure, showed nearly 60% heart failure attenuation. C25, a chalcone derivative, and A11, a phenolic compound, showed around 80% and 90% attenuation, respectively. Time course experiments revealed that, to obtain 50% efficacy, these compounds were required within different hours of AA treatment. Furthermore, quantitative polymerase chain reaction showed that C25, not MEK-I or A11, strongly suppressed inflammation. Finally, C25 and MEK-I, but not A11, could also rescue the doxorubicin-induced heart failure in zebrafish embryos. In summary, we have established two tractable heart failure models for drug discovery and three potential drugs have been identified that seem to attenuate heart failure by different mechanisms.

A complete diet-based algorithm for predicting nonheme iron absorption in adults.

Many algorithms have been developed in the past few decades to estimate nonheme iron absorption from the diet based on single meal absorption studies. Yet single meal studies exaggerate the effect of diet and other factors on absorption. Here, we propose a new algorithm based on complete diets for estimating nonheme iron absorption. We used data from 4 complete diet studies each with 12-14 participants for a total of 53 individuals (19 men and 34 women) aged 19-38 y. In each study, each participant was observed during three 1-wk periods during which they consumed different diets. The diets were typical, high, or low in meat, tea, calcium, or vitamin C. The total sample size was 159 (53 × 3) observations. We used multiple linear regression to quantify the effect of different factors on iron absorption. Serum ferritin was the most important factor in explaining differences in nonheme iron absorption, whereas the effect of dietary factors was small. When our algorithm was validated with single meal and complete diet data, the respective R(2) values were 0.57 (P < 0.001) and 0.84 (P < 0.0001). The results also suggest that between-person variations explain a large proportion of the differences in nonheme iron absorption. The algorithm based on complete diets we propose is useful for predicting nonheme iron absorption from the diets of different populations.

Modified array-based comparative genomic hybridization detects cryptic and variant PML-RARA rearrangements in acute promyelocytic leukemia lacking classic translocations.

Acute promyelocytic leukemia (APL) is typically defined at the molecular level by a reciprocal translocation of the promyelocytic leukemia (PML) and retinoic acid receptor α (RARA) genes. An accurate diagnosis of APL is critical for appropriate choice of therapy and prognostic assessment. Cryptic and variant rearrangements in APL are discoverable by a variety of molecular methods including fluorescence in situ hybridization (FISH), reverse transcriptase polymerase chain reaction, or gene sequencing. Rare reports of FISH-negative APL harboring cryptic rearrangements of PML-RARA detected by reverse transcriptase polymerase chain reaction or sequencing have been described. Here, we describe the detection of cryptic or variant PML-RARA rearrangements by translocation-based comparative genomic hybridization (tCGH), a recently described modification of traditional CGH technology that facilitates the detection of balanced translocations by means of the linear amplification of a potential translocation breakpoint region(s), in 2 unusual cases of APL. One tumor lacked detectable t(15;17) by karyotype and FISH, and the other tumor lacked the typical morphologic and immunophenotypic features of APL and had a variant 3-way translocation involving PML and RARA. PML-RARA translocations were identified by tCGH in both cases providing confirmation of the diagnosis of APL. These data emphasize the benefit of using complementary molecular methods including tCGH for detecting cryptic and variant PML-RARA translocations in unusual cases of APL.