Manipulating the Circadian and Sleep Cycles to Protect Against Metabolic Disease

Modernization of human society parallels an epidemic of metabolic disorders including obesity. Apart from excess caloric intake, a 24/7 lifestyle poses another important challenge to our metabolic health. Recent research under both laboratory and epidemiological settings has indicated that abnormal temporal organization of sleep and wakeful activities including food intake is a significant risk factor for metabolic disease. The circadian clock system is our intrinsic biological timer that regulates internal rhythms such as the sleep/wake cycle and also responses to external stimuli including light and food. Initially thought to be mainly involved in the timing of sleep, the clock and/or clock genes may also play a role in sleep architecture and homeostasis. Importantly, an extensive body of evidence has firmly established a master regulatory role of the clock in energy balance. Together, a close relationship between well-timed circadian/sleep cycles and metabolic health is emerging. Exploiting this functional connection, an important holistic strategy toward curbing the epidemic of metabolic disorders (e.g. obesity) involves corrective measures on the circadian clock and sleep. In addition to behavioral and environmental interventions including meal timing and light control, pharmacological agents targeting sleep and circadian clocks promise convenient and effective applications. Recent studies, for example, have reported small molecules targeting specific clock components and displaying robust beneficial effects on sleep and metabolism. Furthermore, a group of clock-amplitude enhancing small molecules (CEMs) identified via high-throughput chemical screens are of particular interest for future in vivo studies of their metabolic and sleep efficacies. Elucidating the functional relationship between clock, sleep and metabolism will also have far-reaching implications for various chronic human diseases and aging

Buy genuine luxury fashion products or counterfeits

The research examined the effect of three groups of variables on purchase intention of luxury fashion designer brands and their corresponding counterfeits: past behavior (past purchases of counterfeits and originals), attitudes toward buying counterfeits (by economic and hedonic benefits), and individual characteristics (materialism, perception of future social status, and self-image). Data of 324 Korean female students confirmed that the variables were determinants of purchase intention of counterfeits and originals and that purchase intention of counterfeits was positively related to purchase intention of originals whereas purchase intention of originals was negatively related to purchase intention of counterfeits. This work is copyrighted by The Association for Consumer Research. For permission to copy or use this work in whole or in part, please contact the Copyright Clearance Center at http://www.copyright.com/. 280 Advances in Consumer Research Volume 36, © 2009 Buy Genuine Luxury Fashion Products or Counterfeits? Boonghee Yoo, Hofstra University, USA Seung-Hee Lee, Kent State University, USA 1 1 The authors acknowledge that this research was supported by a summer research grant from the Frank G. Zarb School of Business, Hofstra University. ABSTRACT The research examined the effect of three groups of variables on purchase intention of luxury fashion designer brands and their corresponding counterfeits: past behavior (past purchases of counterfeits and originals), attitudes toward buying counterfeits (by economic and hedonic benefits), and individual characteristics (materialism, perception of future social status, and self-image). Data of 324 Korean female students confirmed that the variables were determinants of purchase intention of counterfeits and originals and that purchase intention of counterfeits was positively related to purchase intention of originals whereas purchase intention of originals was negatively related to purchase intention of counterfeits

Circadian stabilization loop: the regulatory hub and therapeutic target promoting circadian resilience and physiological health [version 2; peer review: 2 approved]

The circadian clock is a fundamental biological mechanism that orchestrates essential cellular and physiological processes to optimize fitness and health. The basic functional unit is the cell-autonomous oscillator, consisting of intersecting negative feedback loops. Whereas the core loop is primarily responsible for rhythm generation, auxiliary loops, most notably the secondary or stabilization loop, play pivotal roles to confer temporal precision and molecular robustness. The stabilization loop contains opposing nuclear receptor subfamilies REV-ERBs and retinoic acid receptor-related orphan receptors (RORs), competing to modulate rhythmic expression of the basic helix-loop-helix ARNT like 1 (Bmal1) genes in the core loop as well as other clock-controlled genes. Therefore, REV-ERBs and RORs are strategically located to interface the oscillator and the global transcriptomic network, promoting cellular homeostasis and physiological fitness throughout lifespan. Disruption of REV-ERB and ROR functions has been linked with diseases and aging, and pharmacological manipulation of these factors has shown promise in various mouse disease models. Nobiletin is a natural compound that directly binds to and activates RORα/γ, modulating circadian rhythms, and shows robust in vivo efficacies to combat clock-associated pathophysiologies and age-related decline. Results from several studies demonstrate an inverse relation between nobiletin efficacy and clock functional state, where nobiletin elicits little effect in young and healthy mice with growing efficacy as the clock is perturbed by environmental and genetic challenges. This mode of action is consistent with the function of the stabilization loop to promote circadian and physiological resilience. Future studies should further investigate the function and mechanism of REV-ERBs and RORs, and test strategies targeting these factors against disease and aging

Biochemical characterization of a recombinant Japanese encephalitis virus RNA-dependent RNA polymerase

<p>Abstract</p> <p>Background</p> <p>Japanese encephalitis virus (JEV) NS5 is a viral nonstructural protein that carries both methyltransferase and RNA-dependent RNA polymerase (RdRp) domains. It is a key component of the viral RNA replicase complex that presumably includes other viral nonstructural and cellular proteins. The biochemical properties of JEV NS5 have not been characterized due to the lack of a robust <it>in vitro </it>RdRp assay system, and the molecular mechanisms for the initiation of RNA synthesis by JEV NS5 remain to be elucidated.</p> <p>Results</p> <p>To characterize the biochemical properties of JEV RdRp, we expressed in <it>Escherichia coli </it>and purified an enzymatically active full-length recombinant JEV NS5 protein with a hexahistidine tag at the N-terminus. The purified NS5 protein, but not the mutant NS5 protein with an Ala substitution at the first Asp of the RdRp-conserved GDD motif, exhibited template- and primer-dependent RNA synthesis activity using a poly(A) RNA template. The NS5 protein was able to use both plus- and minus-strand 3'-untranslated regions of the JEV genome as templates in the absence of a primer, with the latter RNA being a better template. Analysis of the RNA synthesis initiation site using the 3'-end 83 nucleotides of the JEV genome as a minimal RNA template revealed that the NS5 protein specifically initiates RNA synthesis from an internal site, U₈₁, at the two nucleotides upstream of the 3'-end of the template.</p> <p>Conclusion</p> <p>As a first step toward the understanding of the molecular mechanisms for JEV RNA replication and ultimately for the <it>in vitro </it>reconstitution of viral RNA replicase complex, we for the first time established an <it>in vitro </it>JEV RdRp assay system with a functional full-length recombinant JEV NS5 protein and characterized the mechanisms of RNA synthesis from nonviral and viral RNA templates. The full-length recombinant JEV NS5 will be useful for the elucidation of the structure-function relationship of this enzyme and for the development of anti-JEV agents.</p

Non-invasive flow mapping of parasagittal meningeal lymphatics using 2D interslice flow saturation MRI

The clearance pathways of brain waste products in humans are still under debate in part due to the lack of noninvasive imaging techniques for meningeal lymphatic vessels (mLVs). In this study, we propose a new noninvasive mLVs imaging technique based on an inter-slice blood perfusion MRI called alternate ascending/descending directional navigation (ALADDIN). ALADDIN with inversion recovery (IR) at single inversion time of 2300 ms (single-TI IR-ALADDIN) clearly demonstrated parasagittal mLVs around the human superior sagittal sinus (SSS) with better detectability and specificity than the previously suggested noninvasive imaging techniques. While in many studies it has been difficult to detect mLVs and confirm their signal source noninvasively, the detection of mLVs in this study was confirmed by their posterior to anterior flow direction and their velocities and morphological features, which were consistent with those from the literature. In addition, IR-ALADDIN was compared with contrast-enhanced black blood imaging to confirm the detection of mLVs and its similarity. For the quantification of flow velocity of mLVs, IR-ALADDIN was performed at three inversion times of 2000, 2300, and 2600 ms (three-TI IR-ALADDIN) for both a flow phantom and humans. For this preliminary result, the flow velocity of the dorsal mLVs in humans ranged between 2.2 and 2.7mm/s. Overall, (i) the single-TI IR-ALADDIN can be used as a novel non-invasive method to visualize mLVs in the whole brain with scan time of ~ 17min and (ii) the multi-TI IR-ALADDIN can be used as a way to quantify the flow velocity of mLVs with a scan time of ~ 10min (or shorter) in a limited coverage. Accordingly, the suggested approach can be applied to noninvasively studying meningeal lymphatic flows in general and also understanding the clearance pathways of waste production through mLVs in humans, which warrants further investigation

Antimicrobial peptide from Bacillus subtilis CSB138: characterization, killing kinetics, and synergistic potency

We studied the prospect of synergy between the antimicrobial peptide p138c and non-peptide antibiotics for increasing the potency and bacterial killing kinetics of these agents. The production of p138c was maximized in the late exponential growth phase of Bacillus subtilis CSB138. Purification of p138c resulted in a total of 4800 arbitrary units (AU) with 19.15-fold and 3.2% recovery. Peptide p138c was thermo-tolerant up to 50 &deg;C and stable at pH 5.8 to 11. The biochemical nature of p138c was determined by a bioassay, similar to tricine-SDS-PAGE, indicating inhibition at 3 kDa. The amino acid sequence of p138c was Gly-Leu-Glu-Glu-Thr-Val-Tyr-Ile-Tyr-Gly-Ala-Asn-Met-X-Ser. Potency and killing kinetics against vancomycin-resistant Staphylococcus aureus improved considerably when p138c was synergized with oxacillin, ampicillin, and penicillin G. The minimal inhibitory concentration (MIC) of p138c showed a 4-, 8-, and 16-fold improvement when p138c was combined with oxacillin, ampicillin, and penicillin G, respectively. The fractional inhibitory concentration index for the combination of p138c and oxacillin, ampicillin, and penicillin G was 0.3125, 0.25, and 0.09, respectively. Synergy with non-peptide antibiotics resulted in enhanced killing kinetics of p138c. Hence, the synergy between antimicrobial peptide and non-peptide antibiotics may enhance the potency and bacterial killing kinetics, providing more potent and rapidly acting agents for therapeutic use. [Int Microbiol 20(1):43-53 (2017)]Keywords: Bacillus subtilis &middot; antimicrobial peptides &middot; killing kinetic

The first-line cluster headache medication verapamil alters the circadian period and elicits sex-specific sleep changes in mice

Verapamil is the first-line preventive medication for cluster headache, an excruciating disorder with strong circadian features. Whereas second- and third-line preventives include known circadian modulators, such as melatonin, corticosteroids, and lithium, the circadian effects of verapamil are poorly understood. Here, we characterize the circadian features of verapamil using both in vitro and in vivo models. In Per2::LucSV reporter fibroblasts, treatment with verapamil (0.03–10 µM) showed a dose-dependent period shortening of the reporter rhythm which reached a nadir at 1 µM, and altered core clock gene expression at 10 µM. Mouse wheel-running activity with verapamil (1 mg/mL added to the drinking water) also resulted in significant period shortening and activity reduction in both male and female free-running wild-type C57BL6/J mice. The temporal patterns of activity reduction, however, differ between the two sexes. Importantly, piezo sleep recording revealed sexual dimorphism in the effects of verapamil on sleep timing and bout duration, with more pronounced adverse effects in female mice. We also found altered circadian clock gene expression in the cerebellum, hypothalamus, and trigeminal ganglion of verapamil-treated mice. Verapamil did not affect reporter rhythms in ex vivo suprachiasmatic nucleus (SCN) slices from Per2:Luc reporter mice, perhaps due to the exceptionally tight coupling in the SCN. Thus, verapamil affects both peripheral (trigeminal ganglion) and central (hypothalamus and cerebellum) nervous system structures involved in cluster headache pathophysiology, possibly with network effects instead of isolated SCN effects. These studies suggest that verapamil is a circadian modulator in laboratory models at both molecular and behavioral levels, and sex is an important biological variable for cluster headache medications. These observations highlight the circadian system as a potential convergent target for cluster headache medications with different primary mechanisms of action

Variability of Response Time as a Predictor of Methylphenidate Treatment Response in Korean Children with Attention Deficit Hyperactivity Disorder

PURPOSE: Methylphenidate (MPH) is an effective medication for the treatment of attention deficit hyperactivity disorder (ADHD). However, about 30% of patients do not respond to or are unable to tolerate MPH. Based on previous findings, we hypothesized that great variability in response time (RT) among Korean children with ADHD on a computerized continuous performance attention test would be related to poor MPH treatment response. MATERIALS AND METHODS: Children (ages 6-18 years) with ADHD were recruited for a prospective 12-week, open-labeled, multicenter study to examine optimal dosage of OROS methylphenidate. Of the 144 subjects selected, 28 dropped out due to adverse events, medication noncompliance, or follow-up loss, and an additional 26 subjects with comorbid disorders were excluded from statistical analyses. We defined 'responders' as subjects who received a score of less than 18 on the attention deficit hyperactivity disorder rating scale (ARS; Korean version, K-ARS) and a score of 1 or 2 on the Clinical Global Impression-Improvement scale (CGI-I). RT variability was assessed with the ADHD diagnostic system (ADS). RESULTS: Fifty-nine (67%) subjects responded to MPH treatment. The non-responders showed greater RT variability at baseline (Mann Whitney U = 577.0, p < 0.01). Baseline RT variability was a significant predictor of MPH response (Nagelkerke R(2) = 0.136, p < 0.01). It predicted 94.9% of responder, 17.2% of non-responder and 69.3% of overall group. CONCLUSION: High RT variability may predict poor response to MPH treatment in children with ADHDope

Manumycin from a new Streptomyces strain shows antagonistic effect against methicillin-resistant Staphylococcus aureus (MRSA)/vancomycin-resistant enterococci (VRE) strains from Korean Hospitals

An antimicrobial compound, highly effective against multidrug-resistant (MDR) bacteria, purified from a Streptomyces strain was identified as manumycin. The minimal inhibitory concentrations (MICs) of manumycin against 8 different strains of methicillin-resistant Staphylococcus aureus (MRSA) were ranged 2 to 32 μg/ml. Similarly, MICs of manumycin against 4 vancomycin-resistant enterococci (VRE) strains were ranged 8 to 32 μg/ml while it remained ineffective against 4 other VRE strains. Compared to vancomycin, manumycin provided slightly weaker activity against MRSA strains but stronger activity against 4 VRE strains. This is the first report of antagonistic effect of manumycin against MDR pathogens.Keywords: Manumycin, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE)African Journal of Biotechnology Vol. 12(17), pp. 2249-225