The antioxidant potential of alprazolam on the redox status of peripheral blood leukocytes in restraint-stressed mice

Skeletal Reorganization Emanated via the Course of Heterocyclic N1-N2 Bond Cleavage: Electrosynthetic Approach

A unified method toward the synthesis of functionalized diazepines and quinazolines through reorganization of the molecular skeleton has been devised. The process is indulged by electrical energy via a domino N1-N2 bond cleavage followed by concomitant ring closing, initiating from cinnolines and indazoles as designed precursors. Additionally, an intermolecular ring homologation has also been established to synthesize densely functionalized dihydroquinazolines from 2,3-diaryl-indazoles and acetonitrile involving the same electrochemical strategy.

Lacidipine attenuates caffeine-induced anxiety-like symptoms in mice: Role of calcium-induced oxido-nitrosative stress

BACKGROUND

Anxiety is a disorder of multi-factorial pathogenesis involving interrelated pathways of neurotransmitters, oxidative stress and metamorphosed calcium-signaling that negatively affects brain functions. Modulation of Ca2+-channels outlines a promising strategy to curb the progression of anxiety-like disorders through attenuation of redox-imbalance. The current research scheme was designed to explore the anxiolytic effects of lacidipine (L-type Ca2+-channel blocker; LCD) pretreatment in caffeine-induced anxiety-like symptom model in mice.

METHODS

Forty-two Swiss albino mice (25-30 g) were distributed to 7 groups (n = 6): Vehicle control, caffeine, alprazolam + caffeine, lacidipine(0.3, 1 and 3 mg/kg, ip)+caffeine and Bay-K8644+LCD(3)+caffeine. Caffeine (25 mg/kg, ip) was administered from day 8 to 14 to induce anxiety-like symptoms in mice. Lacidipine (0.3, 1 and 3 mg/kg, ip) and alprazolam (0.25 mg/kg, ip) were administered from day 1 to 14 in separate groups. Bay-K8644 (Ca2+-channel agonist) was injected on day 14 to delineate the role of Ca2+ in anti-anxiety effect of LCD in caffeine-treated mice. Elevated zero maze and mirror chamber test were employed to assess anxiety-like behavior. Afterwards, the mice were sacrificed and whole brains were harvested for estimation of biomarkers of oxido-nitrosative stress, such as TBARS, GSH, SOD, catalase and total nitrite content.

RESULTS

An increase in brain oxido-nitrosative stress and anxiety-like behavior was observed in caffeine treated mice. LCD pretreatment attenuated the brain oxido-nitrosative stress and anxiety-like behavior in mice in caffeine treated mice. Anxiolytic effect of LCD was attenuated by Bay-K8644 (0.5 mg/kg) in caffeine treated mice.

CONCLUSION

LCD (L-type Ca2+-channel antagonist) pretreatment attenuated caffeine-induced oxido-nitrosative stress and anxiety-like behavior.

Intermittent hypoxia training: Powerful, non-invasive cerebroprotection against ethanol withdrawal excitotoxicity

Ethanol intoxication and withdrawal exact a devastating toll on the central nervous system. Abrupt ethanol withdrawal provokes massive release of the excitatory neurotransmitter glutamate, which over-activates its postsynaptic receptors, causing intense Ca2+ loading, p38 mitogen activated protein kinase activation and oxidative stress, culminating in ATP depletion, mitochondrial injury, amyloid β deposition and neuronal death. Collectively, these mechanisms produce neurocognitive and sensorimotor dysfunction that discourages continued abstinence. Although the brain is heavily dependent on blood-borne O2 to sustain its aerobic ATP production, brief, cyclic episodes of moderate hypoxia and reoxygenation, when judiciously applied over the course of days or weeks, evoke adaptations that protect the brain from ethanol withdrawal-induced glutamate excitotoxicity, mitochondrial damage, oxidative stress and amyloid β accumulation. This review summarizes evidence from ongoing preclinical research that demonstrates intermittent hypoxia training to be a potentially powerful yet non-invasive intervention capable of affording robust, sustained neuroprotection during ethanol withdrawal.

Delta Opioid Receptor Signaling Promotes Resilience to Stress Under the Repeated Social Defeat Paradigm in Mice

The adaptation to chronic stress is highly variable across individuals. Resilience to stress is a complex process recruiting various brain regions and neurotransmitter systems. The aim of this study was to investigate the involvement of endogenous opioid enkephalin (ENK) signaling in the development of stress resilience in mice. The translational model of repeated social defeat (RSD) stress was selected to mimic the unpredictable disruptions of daily life and induce resilience or vulnerability to stress. As in humans, adult C57BL/6J mice demonstrated a great variability in their response to stress under this paradigm. A social interaction (SI) test was used to discriminate between the phenotypes of resilience or vulnerability to stress. After social defeat, the expression levels of ENK mRNA and their delta opioid receptors (DOPr) were quantified in the basolateral amygdala (BLA) and BLA-target areas by in situ hybridization. In this manner, ENK mRNA levels were found to decrease in the BLA and those of DOPr in the ventral hippocampus (HPC) CA1 of vulnerable mice only. Stimulating the DOPr pathway during social defeat by pharmacological treatment with the nonpeptide, selective DOPr agonist SNC80 further induced a resilient phenotype in a majority of stressed animals, with the proportion of resilient ones increasing from 33% to 58% of the total population. Ultrastructural analyses additionally revealed a reduction of oxidative stress markers in the pyramidal cells and interneurons of the ventral HPC CA1 upon SNC80 treatment, thus proposing a mechanism by which ENK-DOPr signaling may prevent the deleterious effects of chronic social stress.

Effect of Drug Alprazolam on Restrained Stress Induced Alteration of Serum Cortisol and Antioxidant Vitamins (Vitamin C and E) in Male Albino Rats

INTRODUCTION

Stress can cause harmful effects in the body that induce a wide range of biochemical and behavioural changes. As anti-stress drugs are routinely used to combat stress hence study is needed to assess the contraindication of these drugs in the physiological systems.

AIM

To investigate the effect of alprazolam on restrained stress induced alteration of serum cortisol, and antioxidant vitamin levels in male albino rats.

MATERIALS AND METHODS

Adult male albino rats (body weight 175-225g) were divided into four groups of six animals in each. Group I (control), kept undisturbed in the metabolic cage throughout the 42 days experimental period. Group II (stress) rats were kept in a wire mesh restrainer for 6 hr/day for 42 days. Group III (stress+ withdrawal) rats were stressed for 21 days and withdrawal of stress for remaining 21 days (total 42 days). Group IV (stress + alprazolam) rats were only stressed for 21 days and treated with drug alprazolam (5mg/kg body weight, intraperitoneal) in continuation with stress for remaining 21 days (total period is 42 days). At the end of 42 days all the rats were sacrificed and serum cortisol, vitamin C and E levels were estimated.

RESULTS

Group II (stressed) showed a significant increase in serum cortisol level with concomitant decrease of serum vitamin C and E levels. Group III (withdrawal) and Group IV (+alprazolam) rats showed significant reduction of serum cortisol along with subsequent increase of serum vitamin C and E concentrations.

CONCLUSION

Results indicate a possible antioxidant effect of alprazolam on restrained stress induced alteration of serum cortisol and antioxidant vitamin levels.

Traumatic stress, oxidative stress and post-traumatic stress disorder: neurodegeneration and the accelerated-aging hypothesis

Post-traumatic stress disorder (PTSD) is associated with elevated risk for a variety of age-related diseases and neurodegeneration. In this paper, we review evidence relevant to the hypothesis that chronic PTSD constitutes a form of persistent life stress that potentiates oxidative stress (OXS) and accelerates cellular aging. We provide an overview of empirical studies that have examined the effects of psychological stress on OXS, discuss the stress-perpetuating characteristics of PTSD, and then identify mechanisms by which PTSD might promote OXS and accelerated aging. We review studies on OXS-related genes and the role that they may have in moderating the effects of PTSD on neural integrity and conclude with a discussion of directions for future research on antioxidant treatments and biomarkers of accelerated aging in PTSD.

Oxidative imbalance and anxiety disorders

The oxidative imbalance appears to have an important role in anxiety development. Studies in both humans and animals have shown a strong correlation between anxiety and oxidative stress. In humans, for example, the increased malondialdehyde levels and discrepancies in antioxidant enzymes in erythrocytes have been observed. In animals, several studies also show that anxiety-like behavior is related to the oxidative imbalance. Moreover, anxiety-like behavior can be caused by pharmacological-induced oxidative stress. Studies using knockout or overexpression of antioxidant enzymes have shown a relationship between anxiety-like behavior and oxidative stress. Related factors of oxidative stress that could influence anxious behavior are revised, including impaired function of different mitochondrial proteins, inflammatory cytokines, and neurotrophic factors. It has been suggested that a therapy specifically focus in reducing reactive species production may have a beneficial effect in reducing anxiety. However, the neurobiological pathways underlying the effect of oxidative stress on anxiety symptoms are not fully comprehended. The challenge now is to identify the oxidative stress mechanisms likely to be involved in the induction of anxiety symptoms. Understanding these pathways could help to clarify the neurobiology of the anxiety disorder and provide tools for new discovery in therapies and preventive strategies.

Benzodiazepines: electron affinity, receptors and cell signaling - a multifaceted approach

This report entails a multifaceted approach to benzodiazepine (BZ) action, involving electron affinity, receptors, cell signaling and other aspects. Computations of the electron affinities (EAs) of different BZs have been carried out to establish the effect of various substituents on their EA. These computations were undertaken to serve as a first step in determining what role electron transfer (ET) plays in BZ activity. The calculations were conducted on the premise that the nature of the substituent will either decrease or increase the electron density of the benzene ring, thus altering the ability of the molecule to accept an electron. Investigations were performed on the effect of drug protonation on EA. Similarities involving substituent effects in prior electrochemical studies are also discussed. As part of the multifaceted approach, EA is linked to ET, which appears to play a role in therapeutic activity and toxicity. There is extensive literature dealing with the role of receptors in BZ activity. Significant information on receptor involvement was reported more than 40 years ago. Gamma-aminobutyric acid (GABA) is known to be importantly involved. GABA is a probable mediator of BZ effects. BZ and GABA receptors, although not identical, are physiologically linked. Cell signaling is known to play a part in the biochemistry of BZ action. Various factors participated, such as gene expression, allosteric influence, toxic effects and therapeutic action. Evidence points to involvement of EA and ET in the mode of action in cell signaling. Oxidative stress and antioxidant effects are also addressed.

High phobic anxiety is related to lower leukocyte telomere length in women

Background

Chronic psychological distress has been linked to shorter telomeres, an indication of accelerated aging. Yet, little is known about relations of anxiety to telomeres. We examined whether a typically chronic form of anxiety – phobic anxiety – is related to telomere length.

Methodology/Principal Findings

Relative telomere lengths (RTLs) in peripheral blood leukocytes were measured by quantitative real-time polymerase chain reaction among 5,243 women (aged 42–69 years) who: were participants in the Nurses' Health Study; were controls in prior case-control studies of telomeres and disease, or randomly selected healthy participants in a cognitive function sub-study; had completed the Crown-Crisp phobic index proximal to blood collection. Adjusted least-squares mean RTLs (z-scores) were calculated across phobic categories. Higher phobic anxiety was generally associated with lower RTLs (age-adjusted p-trend = 0.09); this association was similar after adjustment for confounders – paternal age-at-birth, smoking, body mass index (BMI) and physical activity (p-trend = 0.15). Notably, a threshold was identified. Among women with Crown-Crisp<6 points, the multivariable-adjusted least-squares mean RTL z-score = 0.02 standard units; however, among the most phobic women (Crown-Crisp≥6), the multivariable-adjusted least-squares mean RTL z-score = −0.09 standard units (mean difference = −0.10 standard units; p = 0.02). The magnitude of this difference was comparable to that for women 6 years apart in age. Finally, effect modification by BMI, smoking and paternal age was observed: associations were stronger among highly phobic women with BMI≥25 kg/m², without smoking history, or born to fathers aged ≥40 years.

Conclusions/Significance

In this large, cross-sectional study high phobic anxiety was associated with shorter telomeres. These results point toward prospective investigations relating anxiety to telomere length change.

Urinary biopyrrins: potential biomarker for monitoring of the response to treatment with anxiolytics

During periods of psychological stress, excess amounts of free radicals are produced. Bilirubin oxidative metabolites (biopyrrins; BOM) are generated from bilirubin as a result of its scavenging action against free radicals. We investigated whether the urinary excretion of biopyrrins is altered by anxiolytics. In the present study, mice were immobilized for a period of 6 hr. Alprazolam (0.1-1 mg/kg of body-weight) was administered 30 min. before subjecting the animals to acute stress. The BOM concentrations in urine and the corticosterone levels in serum were measured by ELISA with an anti-bilirubin antibody and EIA, respectively. We observed an increase in urinary biopyrrins in stressed mice in comparison with non-stressed mice and a decrease after the treatment of stressed animals with alprazolam. A correlation between urinary BOM and serum corticosterone levels was found. Urinary levels of biopyrrins might be used to assess the response to anxiolytics prescribed during acute stress periods.