Intense exercise increases circulating endocannabinoid and BDNF levels in humans--possible implications for reward and depression

One step at a time: Physical activity is linked to positive interpretations of ambiguity

Background

Extensive research has established a clear positive relationship between physical activity (PA), even in small amounts, and psychological well-being, including benefits for emotional and mental health (e.g., decreased depression). However, little research has examined the relationship between PA and decision-making within emotionally ambiguous contexts. The purpose of the present cross-sectional study was to examine the relationship between reported amount and intensity of PA and interpretations of emotional ambiguity.

Methods

Adults (n = 611) recruited through Amazon’s Mechanical Turk were assessed on their interpretations of ambiguous and clear (unambiguous) emotional stimuli and reported habitual PA and exercise.

Results

More positive ratings of ambiguity were associated with greater amount of vigorous activity (p = .002), but not with moderate activity (p = .826) or walking (p = .673). Subsequent analyses demonstrated that this relationship between vigorous PA and positive interpretations of ambiguity was most pronounced when comparing individuals who reported any amount of vigorous PA to those who reported no vigorous activity at all.

Conclusions

Our findings suggest that higher amounts of vigorous, but not moderate, PA are associated with more positive interpretations of ambiguity, and that even small amounts of PA seem to be sufficient to promote this more positive valence bias when compared to individuals conducting no vigorous PA at all. Future work should examine the longitudinal effects of PA among individuals participating in structured activity programs.

Psychological and endocannabinoid responses to aerobic exercise in substance use disorder patients

BACKGROUND

Exercise has been examined as an adjunctive treatment for substance use disorders (SUDs), yet few exercise interventions have been conducted among patients undergoing intensive outpatient (IOP) treatment, who may be the most vulnerable to relapse and for whom exercise could provide the most benefits. This study examined the effects of aerobic exercise, in addition to IOP treatment, on psychological variables and endocannabinoids in individuals with SUDs. Methods: Twenty-one SUD patients (mean age 35 years) were recruited from local IOPs. Participants were randomized to either treatment-as-usual (TAU, at their outpatient clinic) or TAU plus aerobic exercise training (EX). EX participants engaged in supervised, moderate-intensity exercise for 30 min, 3 times/week for 6 weeks. TAU participants came into the laboratory once per week for assessments and a 30-min quiet rest session. Participants provided blood samples and completed questionnaires evaluating substance use, mood states, depression, anxiety, perceived stress, self-efficacy to abstain from substance use, and craving. Data were analyzed with Mann-Whitney U tests or mixed model ANOVAs to determine group differences in outcomes acutely and over 6 weeks. Results: Over 6 weeks, there were reductions in perceived stress (p < 0.01) and craving (p < 0.05) for both groups. There were no group differences in abstinence rates or changes from baseline in self-efficacy, depression, or anxiety (p > 0.05). Acutely, both exercise and quiet rest sessions led to reductions in craving, tension, depression, anger, confusion, and total mood disturbance (all ps < 0.05). In addition, the EX group experienced acute increases in vigor and circulating concentrations of the endocannabinoid, anandamide (p < 0.01). Conclusions: An adjunctive aerobic exercise program during SUD treatment was associated with similar reductions in perceived stress and drug craving as standard care. Thirty minutes of exercise or quiet rest led to acute improvements in mood, but exercise produced the additional benefit of increases in vigor and circulating anandamide.

Altered circulating endocannabinoids in anorexia nervosa during acute and weight-restored phases: A pilot study

Anorexia nervosa (AN) is an eating disorder characterized by a low food intake and often exceeding exercise, leading to a particularly low body × weight proportion. Patients with AN usually report less hunger than healthy controls. Endogenous endocannabinoids (eCBs), specifically the anandamide, have been associated to hunger, as a meal initiator, but research regarding AN and eCB and inconclusive. In this pilot study, we investigated plasma levels of eCB in inpatients with AN during fasting and after eating, both during the acute AN phase and after weight recovery. After an 8-hr fasting period, blood sample was collected from all participants. After that, participants were given a muffin test meal. Blood samples for the investigation of endogenous eCBs anandamide (N-arachidonoylethanolamide [AEA]) and 2-arachidonoylglycerol (2-AG) were then collected after 120 and 240 min. Participants were only allowed to eat and drink what was offered them during the research. AN reported less hunger than controls during fasting and at the end of the experiment. Also, plasma levels of AEA were significantly smaller in AN in comparison with controls in all time points. No significant difference was found for 2-AG plasma levels. After recovery, no significant difference was found for eCB levels. These findings could be interpreted as an AEA deregulation in AN before and after food intake, which persists after weight recovery. These findings may have implications to the pharmacological treatment of AN and to relapse occurring in the disorder.

The Transcriptional Signature of a Runner's High

INTRODUCTION

Endorphins, endocannabinoids, monoamines, and neurotrophins have all been implicated in the euphoric response to endurance running, known as a runner's high (RH). The epitranscriptional mechanisms regulating this effect have not been defined. Here, we investigate peripheral micro-ribonucleic acid (miRNA) changes unique to athletes experiencing postrun euphoria, yielding insights into gene networks that control an RH.

METHODS

A cohort study involving 25 collegiate runners (48% females, age = 20 ± 1 yr) examined salivary RNA levels before and after a long-distance run. Participants were divided into RH and nonrunner's high (NRH) groups based on surveys of four criteria (mood, lost sense of time, run quality, and euphoria). Physiological measures were also recorded (temperature, heart rate, blood pressure, pupillary dilatation, and salivary serotonin). Levels of miRNAs and their messenger RNA targets were compared across pre- and postrun samples from RH and NRH groups with two-way ANOVA. Representation of opioid, gamma-aminobutyic acid (GABA), endocannabinoid, neurotrophin, serotonergic, and dopaminergic pathways was assessed in DIANA miRPath. Pearson's correlation analyses examined relationships between miRNAs and RH indices.

RESULTS

RH participants (n = 13) demonstrated postrun mydriasis (P = 0.046) and hypothermia (P = 0.043) relative to NRH participants (n = 12) but had no difference in serotonin dynamics (P = 0.88). Six miRNAs (miR-194-5p, miR-4676-3p, miR-4254, miR-4425, miR-1273-3p, miR-6743-5p) exhibited significant effects (false discovery rate P value < 0.05) across pre- or postrun and RH/NRH groups. These miRNAs displayed target enrichment for opioid (P = 2.74E-06) and GABA (P = 0.00016) pathways. miR-1237-3p levels were related with lost sense of time (R = 0.40). Mitogen-activated protein kinase (MAPK11), an endocannabinoid target of miR-1273-3p, was nominally elevated in RH participants (false discovery rate P value = 0.11).

CONCLUSIONS

Unique dynamics in miRNA concentration occur in athletes with subjective/objective evidence of RH, targeting genes implicated endorphin, endocannabinoid, and GABAergic signaling.

Impaired brain endocannabinoid tone in the activity-based model of anorexia nervosa

OBJECTIVE

Despite the growing knowledge on the functional relationship between an altered endocannabinoid (eCB) system and development of anorexia nervosa (AN), to date no studies have investigated the central eCB tone in the activity-based anorexia (ABA) model that reproduces key aspects of human AN.

METHOD

We measured levels of two major eCBs, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), those of two eCB-related lipids, oleoylethanolamide (OEA) and palmitoylethanolamide (PEA), and the cannabinoid type-1 receptor (CB1R) density in the brain of female ABA rats, focusing on areas involved in homeostatic and rewarding-related regulation of feeding behavior (i.e., prefrontal cortex, nucleus accumbens, caudato putamen, amygdala, hippocampus and hypothalamus). Analysis was carried out also at the end of recovery from the ABA condition.

RESULTS

At the end of the ABA induction phase, 2-AG was significantly decreased in ABA rats in different brain areas but not in the caudato putamen. No changes were detected in AEA levels in any region, whereas the levels of OEA and PEA were decreased exclusively in the hippocampus and hypothalamus. Furthermore, CB1R density was decreased in the dentate gyrus of hippocampus and in the lateral hypothalamus. After recovery, both 2-AG levels and CB1R density were partially normalized in some areas. In contrast, AEA levels became markedly reduced in all the analyzed areas.

DISCUSSION

These data demonstrate an altered brain eCB tone in ABA rats, further supporting the involvement of an impaired eCB system in AN pathophysiology that may contribute to the maintenance of some symptomatic aspects of the disease.

Physical activity and the prevention of depression: A cohort study

OBJECTIVE

This study aims to identify the optimal amount and appropriate state of physical activity for reducing incident depressive symptoms.

METHOD

The data of 107,901 Korean adults who had undergone at least two annual health examinations from 2012 to 2015 were analyzed. At baseline, the amount of physical activity was measured using the International Physical Activity Questionnaire-Short Form and metabolic equivalents (METs)-min/wk., which is the amount of oxygen consumed while sitting at rest per week. In addition, one-year changes in physical activity were categorized into four groups: persistent sedentary, maintenance, relapse, and adoption groups. For the study's endpoint, new-onset depressive symptoms (score of ≥21) were considered, defined by the Center for Epidemiologic Studies Rating Scale for Depression. A Cox proportional hazards model was used to identify the optimal amount and appropriate state of physical activity for reducing incident depressive symptoms.

RESULTS

Compared with sedentary status (<600 METs-min/wk), achieving 1200-3000 METs-min/wk. was associated with a lower risk of incident depressive symptoms, illustrating a U-shaped relationship. The results show that the amount of physical activity for reducing the onset of depressive symptoms was higher for men (1800-3000 METs-min/wk.: HR, 0.84 [95% CI, 0.74-0.95]) than women (1200-1800 METs-min/wk.: HR, 0.84 [95% CI, 0.71-0.99]). In terms of one-year changes in physical activity, compared to the persistent sedentary group, the maintenance group was associated with a lower risk of the development of depressive symptoms in both sexes (men: HR, 0.81 [95% CI, 0.71-0.93]; women: HR, 0.84 [95% CI, 0.75-0.94]). Women in the adoption group showed a positive effect in terms of a decrease in incident depressive symptoms (HR, 0.87 [95% CI, 0.76-0.99]).

CONCLUSIONS

This study suggests an optimal amount of physical activity for reducing the onset of depressive symptoms. In addition, maintaining an appropriate level of physical activity for one year proved beneficial for decreasing incident depressive symptoms.

Lifestyle and Metabolic Syndrome: Contribution of the Endocannabinoidome

Lifestyle is a well-known environmental factor that plays a major role in facilitating the development of metabolic syndrome or eventually exacerbating its consequences. Various lifestyle factors, especially changes in dietary habits, extreme temperatures, unusual light-dark cycles, substance abuse, and other stressful factors, are also established modifiers of the endocannabinoid system and its extended version, the endocannabinoidome. The endocannabinoidome is a complex lipid signaling system composed of a plethora (>100) of fatty acid-derived mediators and their receptors and anabolic and catabolic enzymes (>50 proteins) which are deeply involved in the control of energy metabolism and its pathological deviations. A strong link between the endocannabinoidome and another major player in metabolism and dysmetabolism, the gut microbiome, is also emerging. Here, we review several examples of how lifestyle modifications (westernized diets, lack or presence of certain nutritional factors, physical exercise, and the use of cannabis) can modulate the propensity to develop metabolic syndrome by modifying the crosstalk between the endocannabinoidome and the gut microbiome and, hence, how lifestyle interventions can provide new therapies against cardiometabolic risk by ensuring correct functioning of both these systems.

Low intensity blood flow restriction exercise: Rationale for a hypoalgesia effect

Exercise-induced hypoalgesia is characterised by a reduction in pain sensitivity following exercise. Recently, low intensity exercise performed with blood flow restriction has been shown to induce hypoalgesia. The purpose of this manuscript is to discuss the mechanisms of exercise-induced hypoalgesia and provide rationale as to why low intensity exercise performed with blood flow restriction may induce hypoalgesia. Research into exercise-induced hypoalgesia has identified several potential mechanisms, including opioid and endocannabinoid-mediated pain inhibition, conditioned pain modulation, recruitment of high threshold motor units, exercise-induced metabolite production and an interaction between cardiovascular and pain regulatory systems. We hypothesise that several mechanisms consistent with prolonged high intensity exercise may drive the hypoalgesia effect observed with blood flow restriction exercise. These are likely triggered by the high level of intramuscular stress in the exercising muscle generated by blood flow restriction including hypoxia, accumulation of metabolites, accelerated fatigue onset and ischemic pain. Therefore, blood flow restriction exercise may induce hypoalgesia through similar mechanisms to prolonged higher intensity exercise, but at lower intensities, by changing local tissue physiology, highlighting the importance of the blood flow restriction stimulus. The potential to use blood flow restriction exercise as a pain modulation tool has important implications following acute injury and surgery, and for several load compromised populations with chronic pain.

Conhecimento de adolescentes acerca dos benefícios do exercício físico para a saúde mental

Resumo A adolescência é uma fase de várias transformações estruturais e funcionais. O exercício físico é capaz de promover plasticidade adaptativa sobre o sistema nervoso, reduzindo os riscos de futuras patologias psiquiátricas. Essa pesquisa teve como objetivo investigar o conhecimento dos adolescentes acerca dos benefícios do exercício físico sobre a saúde mental. Trata-se de um estudo transversal, realizado em uma escola estadual de um município do Centro-Oeste de Minas Gerais. Para coleta de dados, além de um questionário próprio desenvolvido para medir o conhecimento acerca dos benefícios do Exercício Físico sobre a Saúde Mental, foram utilizados o International Physical Activity Questionnaire, e o questionário socioeconômico da Associação Brasileira de Empresas de Pesquisa. Os dados foram analisados por meio de ferramentas de estatística descritiva e pelos testes de Kruskal-Wallis e de qui-quadrado, a um nível de significância de 5%. Verificou-se que indivíduos mais ativos possuíam maior conhecimento acerca dos benefícios do exercício físico para a saúde mental em relação aos indivíduos sedentários. Assim, o conhecimento pode ser um fator protetor contra o sedentarismo e a inatividade física, melhorando significativamente o aspecto relacionado à qualidade de vida do adolescente.

Examination of the comfort and pain experienced with blood flow restriction training during post-surgery rehabilitation of anterior cruciate ligament reconstruction patients: A UK National Health Service trial

OBJECTIVE

Examine the comfort and pain experienced with blow flow restriction resistance training (BFR-RT) compared to standard care heavy load resistance training (HL-RT) during anterior cruciate ligament reconstruction (ACLR) patient rehabilitation.

DESIGN

Randomised controlled trial.

SETTING

United Kingdom National Health Service.

PARTICIPANTS

Twenty eight patients undergoing unilateral ACLR surgery with hamstring autograft were recruited. Following surgery participants were block randomised to either HL-RT at 70% repetition maximum (1RM) (n = 14) or BFR-RT (n = 14) at 30% 1RM and completed 8 weeks of twice weekly unilateral leg press training on both limbs.

MAIN OUTCOME MEASURES

Perceived knee pain, muscle pain and rating of perceived exertion (RPE) were assessed using Borg's (1998) RPE and pain scales during training. Knee pain was also assessed 24 h post-training.

RESULTS

There were no adverse events. Knee pain was lower with BFR-RT during (p < 0.05) and at 24 h post-training (p < 0.05) with BFR-RT for all sessions. Muscle pain was higher (p < 0.05) with BFR-RT compared to HL-RT during all sessions. RPE remained unchanged (p > 0.05) for both BFR-RT and HL-RT.

CONCLUSION

ACLR patients experienced less knee joint pain and reported similar ratings of perceived exertion during and following leg press exercise with BFR-RT compared to traditional HL-RT. BFR-RT may be more advantageous during the early phases of post-surgery ACLR rehabilitation.

A systematic review of existing peripheral biomarkers of cognitive aging: Is there enough evidence for biomarker proxies in behavioral modification interventions?: An initiative in association with the nutrition, exercise and lifestyle team of the Canadian Consortium on Neurodegeneration in Aging

Peripheral biomarkers have shown significant value in predicting brain health and may serve as a useful proxy measurement in the assessment of evidence-based lifestyle behavior modification programs, including physical activity and nutrition programs, that aim to maintain cognitive function in late life. The aim of this systematic review was to elucidate which peripheral biomarkers are robustly associated with cognitive function among relatively healthy non-demented older adults. Following the standards for systematic reviews (PICO, PRIMSA), and employing MEDLINE and Scopus search engines, 222 articles were included in the review. Based on the review of biomarker proxies of cognitive health, it is recommended that a comprehensive biomarker panel, or biomarker signature, be developed as a clinical end point for behavior modification trials aimed at enhancing cognitive function in late life. The biomarker signature should take a multisystemic approach, including lipid, immune/inflammatory, and metabolic biomarkers in the biological signature index of cognitive health.

Stimulation of Peroxisome Proliferator-Activated Receptor-α by N-Palmitoylethanolamine Engages Allopregnanolone Biosynthesis to Modulate Emotional Behavior

BACKGROUND

The endocannabinoid and neurosteroid systems regulate emotions and stress responses. Activation of peroxisome proliferator-activated receptor (PPAR)-α by the endocannabinoid congener N-palmitoylethanolamine (PEA) regulates pathophysiological systems (e.g., inflammation, oxidative stress) and induces peripheral biosynthesis of allopregnanolone, a gamma-aminobutyric acidergic neurosteroid implicated in mood disorders. However, effects of PPAR-α on emotional behavior are poorly understood.

METHODS

We studied the impact of PPAR-α activation on emotional behavior in a mouse model of posttraumatic stress disorder. Neurosteroid levels before and after PEA treatment were measured by gas chromatography-mass spectrometry in relevant brain regions of socially isolated versus group-housed mice exposed to the contextual fear conditioning test, elevated plus maze test, forced swim test, and tail suspension test. Neurosteroidogenic enzyme levels were quantified in hippocampus by Western blot.

RESULTS

PEA administered in a model of conditioned contextual fear reconsolidation blockade facilitated fear extinction and fear extinction retention and induced marked antidepressive- and anxiolytic-like effects in socially isolated mice with reduced brain allopregnanolone levels. These effects were mimicked by the PPAR-α synthetic agonists, fenofibrate and GW7647, and were prevented by PPAR-α deletion, PPAR-α antagonists, and neurosteroid-enzyme inhibitors. Behavioral improvements correlated with PEA-induced upregulation of PPAR-α, neurosteroidogenic enzyme expression, and normalization of corticolimbic allopregnanolone levels.

CONCLUSIONS

This evidence supports a previously unknown role for PPAR-α in behavior regulation and suggests new strategies for the treatment of neuropsychopathologies characterized by deficient neurosteroidogenesis, including posttraumatic stress disorder and major depressive disorder.

Social isolation as a promising animal model of PTSD comorbid suicide: neurosteroids and cannabinoids as possible treatment options

Post-traumatic stress disorder (PTSD) is a psychiatric condition characterized by drastic alterations in mood, emotions, social abilities and cognition. Notably, one aspect of PTSD, particularly in veterans, is its comorbidity with suicide. Elevated aggressiveness predicts high-risk to suicide in humans and despite the difficulty in reproducing a complex human suicidal behavior in rodents, aggressive behavior is a well reproducible behavioral trait of suicide. PTSD animal models are based on a peculiar phenotype, including exaggerated fear memory and impaired fear extinction associated with neurochemical dysregulations in the brain circuitry regulating emotion. The endocannabinoid and the neurosteroid systems regulate emotions and stress responses, and recent evidence shows these two systems are interrelated and critically compromised in neuropsychiatric disorders. For instance, levels of the neurosteroid, allopregnanolone, as well as those of the endocannabinoids, anandamide and its congener, palmitoylethanolamide are decreased in PTSD. Similarly, the endocannabinoid system and neurosteroid biosynthesis are altered in suicidal individuals. Selective serotonin reuptake inhibitors (SSRIs), the only FDA-approved treatments for PTSD, fail to help half of the treatment-seeking patients. This highlights the need for developing biomarker-based efficient therapies. One promising alternative to SSRIs points to stimulation of allopregnanolone biosynthesis as a treatment and a valid end-point to predict treatment response in PTSD patients. This review highlights running findings on the role of the endocannabinoid and neurosteroid systems in PTSD and suicidal behavior both in a preclinical and clinical perspective. A specific focus is given to predictive PTSD/suicide animal models. Ultimately, we discuss the idea that disruption of neurosteroid and endocannabinoid biosynthesis may offer a novel promising biomarker axis to develop new treatments for PTSD and, perhaps, suicidal behavior.

Is Experimental Evolution of an Increased Aerobic Exercise Performance in Bank Voles Mediated by Endocannabinoid Signaling Pathway?

The level of physical activity achieved in a given situation depends on both physiological abilities and behavioral characteristics (motivation). We used a unique animal model to test a hypothesis that evolution of an increased aerobic exercise performance can be facilitated by evolution of motivation to undertake physical activity, mediated by brain endocannabinoid system. Bank voles (Myodes glareolus) from "aerobic" A lines selected for 22 generations for high swim-induced aerobic metabolism (VO2swim) achieved 65% higher "voluntary maximum" VO2swim than voles from unselected, "control" C lines. In C lines, VO2swim was 24% lower than the maximum forced-running aerobic metabolism (VO2run), while in A lines VO2swim and VO2run were practically the same. Thus, the selection changed both the aerobic capacity and motivation to exercise at the top performance level. We applied a pharmacological treatment manipulation to test a hypothesis that the endocannabinoid signaling pathway 1) affects the voles performance in the aerobic exercise trials, and 2) has been modified in the selection process. Administration of the CB1 receptor antagonist (Rimonabant) did not affect the level of metabolism, but administration of the endocannabinoid reuptake inhibitor (AM404) decreased VO2swim both in A and C lines (4%, p = 0.03) and tended to decrease VO2run (2%, p = 0.07). The significant effect of AM404 suggests the involvement of endocannabinoids in signaling pathways controlling the motivation to be active. However, the response to AM404 did not differ between A and C lines (interaction effect, p ≥ 0.29). Thus, the results did not provide a support to the hypothesis that modifications of endocannabinoid signaling have played a role in the evolution of increased aerobic exercise performance in our experimental evolution model system.

SUMMARY STATEMENT

The results corroborated involvement of endocannabinoids in the regulation of physical activity, but did not support the hypothesis that modification of endocannabinoid signaling played a role in the evolution of increased aerobic exercise performance in our experimental evolution model.

Influence of Prolonged Visual Display Terminal Use and Exercise on Physical and Mental Conditions of Internet Staff in Hangzhou, China

To examine the effects of prolonged visual display terminal (VDT) working hours and exercise frequency on VDT-related symptoms, we recruited 944 Chinese internet staff for the study. A self-administered questionnaire survey was used to obtain the hours of daily VDT work, exercise frequency, and the physical and mental health of the participants. The daily VDT working time of participants was 8.7 hours. Musculoskeletal pain and eye complaints were prevalent, and the participants had poor mental health status. When daily VDT operation time was more than 11 hours, VDT-related symptoms, including backache (odds ratios (OR) = 3.59), wrist pain (OR = 1.88), hip pain (OR = 2.42), dry eyes (OR = 2.22), and ocular soreness (OR = 2.16) were more likely to occur, and an increased risk of serious occupational stress (OR = 6.75) and job burnout (OR = 2.66) was found in internet workers. Compared with those who never exercised, appropriate exercise frequency (three times per week) was helpful to relieve pain in the shoulders (OR = 0.28), neck (OR = 0.45), back (OR = 0.30), lower back (OR = 0.25), and wrists (OR = 0.38), as well as to prevent vision loss (OR = 0.33) and job burnout (OR = 0.42). Therefore, avoiding excessive VDT exposure and performing moderate exercise could protect the physical and mental health of internet staff from the adverse effects of VDT.

Physiotherapy Based on a Biobehavioral Approach with or Without Orthopedic Manual Physical Therapy in the Treatment of Nonspecific Chronic Low Back Pain: A Randomized Controlled Trial

Objective

To compare the effectiveness of a biobehavioral approach with and without orthopedic manual physical therapy on the intensity and frequency of pain in patients diagnosed with nonspecific chronic low back pain.

Methods

A single-blind randomized controlled trial. Fifty patients were randomly allocated into two groups: one group received biobehavioral therapy with orthopedic manual physical therapy, and the other group received only biobehavioral therapy. Both groups completed a total of eight sessions, with a frequency of two sessions per week. The somatosensory, physical, and psychological variables were recorded at baseline and during the first and third month after initiation of treatment.

Results

In both groups, the treatment was effective, presenting significant differences for all the variables in the time factor. There were no significant differences between groups in intensity or frequency of pain, with a large effect size (&gt;0.80), but there were intragroup differences for both intervention groups at one- and three-month follow-up. There were also no significant differences between groups in the secondary variables during the same follow-up period.

Conclusions

The results of this study suggest that orthopedic manual physical therapy does not increase the effects of a treatment based on biobehavioral therapy in the short or medium term, but these results should be interpreted with caution.

Multiple endocannabinoid-mediated mechanisms in the regulation of energy homeostasis in brain and peripheral tissues

The endocannabinoid (eCB) system is widely expressed in many central and peripheral tissues, and is involved in a plethora of physiological processes. Among these, activity of the eCB system promotes energy intake and storage, which, however, under pathophysiological conditions, can favour the development of obesity and obesity-related disorders. It is proposed that eCB signalling is evolutionary beneficial for survival under periods of scarce food resources. Remarkably, eCB signalling is increased both in hunger and in overnutrition conditions, such as obesity and type-2 diabetes. This apparent paradox suggests a role of the eCB system both at initiation and at clinical endpoint of obesity. This review will focus on recent findings about the role of the eCB system controlling whole-body metabolism in mice that are genetically modified selectively in different cell types. The current data in fact support the notion that eCB signalling is not only engaged in the development but also in the maintenance of obesity, whereby specific cell types in central and peripheral tissues are key sites in regulating the entire body's energy homeostasis.

Endocannabinoid signaling in psychiatric disorders: a review of positron emission tomography studies

Endocannabinoid signaling is implicated in an array of psychopathologies ranging from anxiety to psychosis and addiction. In recent years, radiotracers targeting the endocannabinoid system have been used in positron emission tomography (PET) studies to determine whether individuals with psychiatric disorders display altered endocannabinoid signaling. We comprehensively reviewed PET studies examining differences in endocannabinoid signaling between individuals with psychiatric illness and healthy controls. Published studies evaluated individuals with five psychiatric disorders: cannabis use disorder, alcohol use disorder, schizophrenia, post-traumatic stress disorder, and eating disorders. Most studies employed radiotracers targeting cannabinoid receptor 1 (CB1). Cannabis users consistently demonstrated decreased CB1 binding compared to controls, with normalization following short periods of abstinence. Findings in those with alcohol use disorder and schizophrenia were less consistent, with some studies demonstrating increased CB1 binding and others demonstrating decreased CB1 binding. Evidence of aberrant CB1 binding was also found in individuals with anorexia nervosa and post-traumatic stress disorder, but limited data have been published to date. Thus, existing evidence suggests that alterations in endocannabinoid signaling are present in a range of psychiatric disorders. Although recent efforts have largely focused on evaluating CB1 binding, the synthesis of new radiotracers targeting enzymes involved in endocannabinoid degradation, such as fatty acid amide hydrolase, will allow for other facets of endocannabinoid signaling to be evaluated in future studies.

Effects of Exercise on Depression, Anxiety, Cognitive Control, Craving, Physical Fitness and Quality of Life in Methamphetamine-Dependent Patients

Methamphetamine (MA) abuse results in a variety of harmful changes in mood states and cognitive function, together with declined physical health and quality of life. Recent studies highlighted the therapeutic potential of physical exercise on MA addiction. Physical exercise improves emotional state and general health conditions, enhances cognitive function, reduces relapse rate, and facilitates abstinence, thereby improves the overall quality of life of the drug users. This review summarizes the present situation of physical exercise on MA-dependent patients with both animal and clinical population results.

Weight loss and improved mood after aerobic exercise training are linked to lower plasma anandamide in healthy people

Anandamide, a major endocannabinoid, participates in energy metabolism homeostasis and neurobehavioral processes. In a secondary analysis of an open-label, randomized controlled trial, we investigated the long-term effect of aerobic exercise on resting plasma anandamide, and explored its relationship with changes in body weight, cardiorespiratory fitness, and mood status in healthy, physically inactive individuals. Participants recruited between March 2013 to August 2015 at the UNIFESP's Neurology/Psychobiology Department were randomly allocated into a 12-weeks supervised moderate exercise program, or into waitlist, control condition. Thirty-four participants (age = 38 ± 11.5, BMI = 26.6 ± 3.6) were intention to treat-analysed (Exercise: n = 17; Control: n = 17). After intervention, there were significant decreases in plasma anandamide (p < .01), anger, anxiety, and body weight (all p < .05), whereas cardiorespiratory fitness increased (p < .05) in the exercise group. There were no significant changes in any variable for the control group. In the whole cohort, adjusted R² of multiple linear regressions showed that 12.2% of change body weight was explained by changes in anandamide (β = 0.391, p = .033), while 27% of change in mood disturbance (β = 0.546, p = .003), and 13.1% of change in anger (β = 0.404, p = .03) was explained by changes in anandamide. Our data suggest that the weight loss and mood improvement through regular moderate exercise may involve changes in anandamide metabolism/signaling. Trials registration: #NCT01972607.

Oleoylethanolamide: A novel pharmaceutical agent in the management of obesity-an updated review

Obesity as a multifactorial disorder has been shown a dramatically growing trend recently. Besides genetic and environmental factors, dysregulation of the endocannabinoid system tone is involved in the pathogenesis of obesity. This study reviewed the potential efficacy of Oleoylethanolamide (OEA) as an endocannabinoid-like compound in the energy homeostasis and appetite control in people with obesity. OEA as a lipid mediator and bioactive endogenous ethanolamide fatty acid is structurally similar to the endocannabinoid system compounds; nevertheless, it is unable to induce to the cannabinoid receptors. Unlike endocannabinoids, OEA negatively acts on the food intake and suppress appetite via various mechanisms. Indeed, OEA as a ligand of PPAR-α, GPR-119, and TRPV1 receptors participates in the regulation of energy intake and energy expenditure, feeding behavior, and weight gain control. OEA delays meal initiation, reduces meal size, and increases intervals between meals. Considering side effects of some approaches used for the management of obesity such as antiobesity drugs and surgery as well as based on sufficient evidence about the protective effects of OEA in the improvement of common abnormalities in people with obese, its supplementation as a novel efficient and FDA approved pharmaceutical agent can be recommended.

Anaerobic Exercise Training in the Therapy of Substance Use Disorders: A Systematic Review

Background: In the past 3 decades, there has been an increase in the number of studies assessing exercise as a form of treatment for substance use disorders (SUDs). While a variety of substance types and outcomes have been assessed, exercise intensities have never been systematically examined. Consequently, it remains unclear whether particular forms of exercise are better suited to the treatment of these populations. Anaerobic exercise has been shown to have positive effects in populations with psychiatric disorders, but its effectiveness in the treatment of SUDs has to date not been reviewed. Methods: The aim of this systematic review is to identify and evaluate studies which have employed either an acute or chronic anaerobic exercise component as a therapy modality for SUDs. The primary outcomes are abstinence, craving, withdrawal, consumption, quality of life, and the following psychological symptoms and disorders: depression, anxiety, stress, and mood. A secondary objective is to assess whether the type of training described in the study protocol can be reliably categorized as anaerobic training. Results: Twenty-six studies are included in this review. Twelve studies addressed nicotine dependence, one addressed alcohol dependence, and 13 addressed dependence on various illicit drugs. Thirteen studies reported the intensity at which participants actually exercised, but only one employed a test to determine whether training was carried out above the anaerobic threshold (AT). The risk of bias in the included studies was generally high. Results of the studies were mixed, with the most positive effects being found for abstinence in nicotine dependence. Conclusion: The evidence for the effects of anaerobic exercise in SUDs is weak, although a tendency toward positive effects on abstinence in nicotine dependent individuals was observable. The majority of studies do not report data on exercise intensity, making a categorization of anaerobic exercise impossible in all but one case. This means that the effects of this form of exercise cannot be determined, and therefore not evaluated or compared with other forms. In order to improve the quality of evidence for exercise in SUD treatment, clearly defined and objectively assessed evaluations of anaerobic and anaerobic exercise are necessary.

Exercise as a reward: Self-paced exercise perception and delay discounting in comparison with food and money

Exercise is an important health behavior. Expressed reasons for participation are often delayed outcomes i.e. health threats and benefits, but also enjoyment. However, we do not know how people evaluate exercise as a reward. The value of rewards diminish the longer we have to wait for them and the discounting effect can undermine decision-making. Here, we investigated delay-discounting of exercise perception and its valuation with time delays; we conducted self-paced exercise sessions on treadmill and compared the discounting rates of exercise (k_ex) with those of established rewards of food (k_fo) and money (k_m). Outcomes show, that young, moderately active participants (n = 70) preferred walking/running intensity with low to moderate cardiovascular strain and light perceived exertion. Delay discounting rates (k) indicated that exercise was discounted like other consumable rewards at the same rate as food and more rapidly than monetary rewards. Significant associations were detected of k_ex with preferred speed and with extrinsic exercise motivation. Exercise training (n = 16) reduced k_ex specifically, not affecting k_fo. Our studies show, that participants perceived and discounted self-paced walking/running like a consumable reward. Exercise discounting was quicker in individuals who preferred lower speeds being less physically active and exercise training reduced the decay rate of exercise specifically.

An Analysis of Endocannabinoid Concentrations and Mood Following Singing and Exercise in Healthy Volunteers

The euphoric feeling described after running is, at least in part, due to increased circulating endocannabinoids (eCBs). eCBs are lipid signaling molecules involved in reward, appetite, mood, memory and neuroprotection. The aim of this study was to investigate whether activities other than running can increase circulating eCBs. Nine healthy female volunteers (mean 61 years) were recruited from a local choir. Circulating eCBs, haemodynamics, mood and hunger ratings were measured before and immediately after 30 min of dance, reading, singing or cycling in a fasted state. Singing increased plasma levels of anandamide (AEA) by 42% (P < 0.05), palmitoylethanolamine (PEA) by 53% (P < 0.01) and oleoylethanolamine (OEA) by 34% (P < 0.05) and improved positive mood and emotions (P < 0.01), without affecting hunger scores. Dancing did not affect eCB levels or hunger ratings, but decreased negative mood and emotions (P < 0.01). Cycling increased OEA levels by 26% (P < 0.05) and tended to decrease how hungry volunteers felt, without affecting mood. Reading increased OEA levels by 28% (P < 0.01) and increased the desire to eat. Plasma AEA levels were positively correlated with how full participants felt (P < 0.05). Plasma OEA levels were positively correlated with positive mood and emotions (P < 0.01). All three ethanolamines were positively correlated with heart rate (HR; P < 0.0001). These data suggest that activities other than running can increase plasma eCBs associated with changes in mood or appetite. Increases in eCBs may underlie the rewarding and pleasurable effects of singing and exercise and ultimately some of the long-term beneficial effects on mental health, cognition and memory.

Could a blood test for PTSD and depression be on the horizon?

INTRODUCTION

Depression and posttraumatic stress disorder (PTSD) are two complex and debilitating psychiatric disorders that result in poor life and destructive behaviors against self and others. Currently, diagnosis is based on subjective rather than objective determinations leading to misdiagnose and ineffective treatments. Advances in novel neurobiological methods have allowed assessment of promising biomarkers to diagnose depression and PTSD, which offers a new means of appropriately treating patients. Areas covered: Biomarkers discovery in blood represents a fundamental tool to predict, diagnose, and monitor treatment efficacy in depression and PTSD. The potential role of altered HPA axis, epigenetics, NPY, BDNF, neurosteroid biosynthesis, the endocannabinoid system, and their function as biomarkers for mood disorders is discussed. Insofar, we propose the identification of a biomarker axis to univocally identify and discriminate disorders with large comorbidity and symptoms overlap, so as to provide a base of support for development of targeted treatments. We also weigh in on the feasibility of a future blood test for early diagnosis. Expert commentary: Potential biomarkers have already been assessed in patients' blood and need to be further validated through multisite large clinical trial stratification. Another challenge is to assess the relation among several interdependent biomarkers to form an axis that identifies a specific disorder and secures the best-individualized treatment. The future of blood-based tests for PTSD and depression is not only on the horizon but, possibly, already around the corner.

Impact of prenatal exercise on both prenatal and postnatal anxiety and depressive symptoms: a systematic review and meta-analysis

Objective

To examine the influence of prenatal exercise on depression and anxiety during pregnancy and the postpartum period.

Design

Systematic review with random effects meta-analysis and meta-regression.

Data sources

Online databases were searched up to 6 January 2017.

Study eligibility criteria

Studies of all designs were included (except case studies) if they were published in English, Spanish or French and contained information on the Population (pregnant women without contraindication to exercise), Intervention (subjective or objective measures of frequency, intensity, duration, volume or type of exercise), Comparator (no exercise or different frequency, intensity, duration, volume and type of exercise) and Outcome (prenatal or postnatal depression or anxiety).

Results

A total of 52 studies (n=131 406) were included. ‘Moderate’ quality evidence from randomised controlled trials (RCTs) revealed that exercise-only interventions, but not exercise+cointerventions, reduced the severity of prenatal depressive symptoms (13 RCTs, n=1076; standardised mean difference: −0.38, 95% CI −0.51 to –0.25, I2=10%) and the odds of prenatal depression by 67% (5 RCTs, n=683; OR: 0.33, 95% CI 0.21 to 0.53, I2=0%) compared with no exercise. Prenatal exercise did not alter the odds of postpartum depression or the severity of depressive symptoms, nor anxiety or anxiety symptoms during or following pregnancy. To achieve at least a moderate effect size in the reduction of the severity of prenatal depressive symptoms, pregnant women needed to accumulate at least 644 MET-min/week of exercise (eg, 150 min of moderate intensity exercise, such as brisk walking, water aerobics, stationary cycling, resistance training).

Summary/Conclusions

Prenatal exercise reduced the odds and severity of prenatal depression.

Partnering with African American Churches to Create a Community Coalition for Mental Health

Community partnered participatory research (CPPR) emphasizes community engagement, respect, and empowerment as guiding principles to promote mental health equity. This article describes the "Vision" stage of a CPPR-informed model to implement evidence-based practices for depression in two African American churches in Harlem, New York. Essential parts of the Vision include engagement of stakeholders and collaborative planning. The engagement process increased awareness about the project via a community-focused mental health symposium. The collaborative planning stage resulted in creating a multi-disciplinary Community Coalition for Mental Health, establishing the Coalition's values, agreeing to change the initial chosen study intervention from Interpersonal Counseling to Mental Health First Aid, and developing a website to disseminate the group's work. Key lessons learned from our partnered process are: 1) support from the lead pastor is crucial; 2) balancing community and academic interests can be challenging; 3) icebreaker activities foster relationships and reinforce CPPR principles; 4) multiple communication channels can enhance community participation; and, 5) should organize data in ways that make them easier to interpret.

Exercise Similarly Facilitates Men and Women's Selective Attention Task Response Times but Differentially Affects Memory Task Performance

Previous research has found that acute, moderate-intensity physical exercise enhances selective attention and memory and that men and women show differential performance on tasks measuring these skills. Although exercise and participant sex have been examined separately, it remains unknown whether acute, moderate-intensity exercise differentially affects men and women’s selective attention and memory encoding and retrieval. Participants in the present study completed two 10-min sessions of either moderate-intensity exercise comprised of jumping rope alternating with walking in place or an active control protocol comprised of watching wellness videos alternating with walking in place. Each participant completed a selective attention task and a task assessing recognition and object location memory immediately after exercising. Exercise was related to overall faster performance during the selective attention task, with no differences in men and women’s performance. Women showed better recognition memory compared to men. Exercise specifically improved object location memory among men, but only among participants who completed the memory task second. These findings suggest that acute, moderate-intensity exercise differentially affects men and women’s memory, which may be related to complex interactions between exercise, sex hormones, and the neurotrophin BDNF.

Pulmonary rehabilitation and BDNF levels in patients with chronic obstructive pulmonary disease: A pilot study

BACKGROUND

COPD physiopathology involves multiple pathways and evidence indicates that brain-derived neurotrophic factor (BDNF) is an important biomarker associated with parameters of COPD severity. This study aimed to analyze the time course of the effects of a pulmonary rehabilitation program (PRP) on BDNF levels and on functional status in COPD patients.

METHODS

Patients were enrolled in a 24-session PRP. Exercise capacity, dyspnea, health-related quality of life, and the BODE index were assessed at baseline and after the PRP. BDNF plasma levels were measured at baseline (immediately before the 1^st session), after the 1^st session, and before and after the 24^th session.

RESULTS

Sixteen patients were included. A reduction in BDNF levels was observed after the 1^st session and an increase was observed between the end of the 1^st session and the beginning of the 24^th session. The PRP promoted an improvement in exercise capacity and health-related quality of life and a reduction in dyspnea and the BODE index.

CONCLUSION

Exercise acutely reduced BDNF levels, an effect that was nullified by the overall intervention.

Masturbation to Orgasm Stimulates the Release of the Endocannabinoid 2-Arachidonoylglycerol in Humans

BACKGROUND

Endocannabinoids are critical for rewarding behaviors such as eating, physical exercise, and social interaction. The role of endocannabinoids in mammalian sexual behavior has been suggested because of the influence of cannabinoid receptor agonists and antagonists on rodent sexual activity. However, the involvement of endocannabinoids in human sexual behavior has not been studied.

AIM

To investigate plasma endocannabinoid levels before and after masturbation in healthy male and female volunteers.

OUTCOMES

Plasma levels of the endocannabinoids 2-arachidonoylglycerol (2-AG), anandamide, the endocannabinoid-like lipids oleoyl ethanolamide and palmitoyl ethanolamide, arachidonic acid, and cortisol before and after masturbation to orgasm.

METHODS

In study 1, endocannabinoid and cortisol levels were measured before and after masturbation to orgasm. In study 2, masturbation to orgasm was compared with a control condition using a single-blinded, randomized, 2-session crossover design.

RESULTS

In study 1, masturbation to orgasm significantly increased plasma levels of the endocannabinoid 2-AG, whereas anandamide, oleoyl ethanolamide, palmitoyl ethanolamide, arachidonic acid, and cortisol levels were not altered. In study 2, only masturbation to orgasm, not the control condition, led to a significant increase in 2-AG levels. Interestingly, we also found a significant increase of oleoyl ethanolamide after masturbation to orgasm in study 2.

CLINICAL TRANSLATION

Endocannabinoids might play an important role in the sexual response cycle, leading to possible implications for the understanding and treatment of sexual dysfunctions.

STRENGTHS AND LIMITATIONS

We found an increase of 2-AG through masturbation to orgasm in 2 studies including a single-blinded randomized design. The exact role of endocannabinoid release as part of the sexual response cycle and the biological significance of the finding should be studied further. Cannabis and other drug use and the attainment of orgasm were self-reported in the present study.

CONCLUSION

Our data indicate that the endocannabinoid 2-AG is involved in the human sexual response cycle and we hypothesize that 2-AG release plays a role in the rewarding consequences of sexual arousal and orgasm. Fuss J, Bindila L, Wiedemann K, et al. Masturbation to Orgasm Stimulates the Release of the Endocannabinoid 2-Arachidonoylglycerol in Humans. J Sex Med 2017;14:1372-1379.

Dutch Translation and Validation of the Headache-Specific Locus of Control Scale (HSLC-DV)

Background and Objective

The assessment of locus of control forms an important part of headache treatment, and there is need to adapting them to the Dutch population.

Methods

Forward-backward translation was used to obtain the Headache-Specific Locus of Control Scale-Dutch Version (HSLC-DV). The response of 87 participants with migraine, tension-type headache, and cervicogenic headache, aged between 18 and 55 years (75% female), is used. Test-retest reliability was measured by intraclass correlations. Construct validity was assessed by correlations with corresponding domains of the Pain Coping and Cognition List (PCCL) and by confirmation of known groups hypotheses. Structural validity was evaluated by factor analysis (principal axis factoring).

Results

The intraclass correlations for the External, Internal, and Chance domains were 0.79, 0.89, and 0.73, respectively. Internal consistencies for domains exceeded 0.73 and were similar to those observed in the original study. Convergent correlations were as expected and three of the seven known groups hypotheses were confirmed. Structural validity was supported by results of the factor analysis that matched the proposed structure of the original instrument.

Conclusions

The HSLC-DV is a valid and reliable questionnaire for measuring the locus of control.

Activity-Based Detection of Cannabinoids in Serum and Plasma Samples

BACKGROUND

Synthetic cannabinoids are the largest group of new psychoactive substances monitored by the European Monitoring Centre of Drugs and Drug Addiction. The rapid proliferation of novel analogs makes the detection of these new derivatives challenging and has initiated considerable interest in the development of so-called “untargeted” screening strategies to detect these compounds.

METHODS

We developed new, stable bioassays in which cannabinoid receptor activation by cannabinoids led to recruitment of truncated β-arrestin 2 (βarr2) to the cannabinoid receptors, resulting in functional complementation of a split luciferase, allowing readout via bioluminescence. Aliquots (500 μL) of authentic serum (n = 45) and plasma (n = 73) samples were used for simple liquid–liquid extraction with hexane:ethyl acetate (99:1 v/v). Following evaporation and reconstitution in 100 μL of Opti-MEM® I/methanol (50/50 v/v), 10 μL of these extracts was analyzed in the bioassays.

RESULTS

Truncation of βarr2 significantly (for both cannabinoid receptors; P = 0.0034 and 0.0427) improved the analytical sensitivity over the previously published bioassays applied on urine samples. The new bioassays detected cannabinoid receptor activation by authentic serum or plasma extracts, in which synthetic cannabinoids were present at low- or sub-nanogram per milliliter concentration or in which Δ9-tetrahydrocannabinol was present at concentrations &gt;12 ng/mL. For synthetic cannabinoid detection, analytical sensitivity was 82%, with an analytical specificity of 100%.

CONCLUSIONS

The bioassays have the potential to serve as a first-line screening tool for (synthetic) cannabinoid activity in serum or plasma and may complement conventional analytical assays and/or precede analytical (mass spectrometry based) confirmation.

Serum endocannabinoids and N-acyl ethanolamines and the influence of simulated solar UVR exposure in humans in vivo

Solar ultraviolet radiation (UVR) exposure of human skin has beneficial and harmful effects on health, including impact on immune function, inflammation and reportedly mood, but these are not fully elucidated. Since the endocannabinoid system is implicated in many activities including mood alteration, our objective was to (i) determine and quantify circulating levels of a wide range of endocannabinoid and N-acyl ethanolamine (NAE) species (ii) evaluate whether these are modulated by cutaneous UVR exposures, as attained through repeated low level summer sunlight exposure. Wearing goggles to prevent eye exposure, 16 healthy volunteers (23-59 y; 10 light skin, phototype II, and 6 dark skin, phototype V) received the same UVR exposures (1.3 SED, 95% UVA/5% UVB) thrice weekly for 6 weeks, whilst casually dressed to expose ∼35% skin surface area. Blood samples were taken at baseline, days 1, 3 and 5 of week one, then at weekly intervals, and analysed by LC-MS/MS. Eleven endocannabinoids and NAEs were detected and quantified at baseline, with N-palmitoyl ethanolamine the most abundant (30% of total). Levels did not vary according to phototype (p > 0.05), except for the NAE docosapentaenoyl ethanolamide, which was higher in phototype II than V (p = 0.0002). Level of the endocannabinoid, 2-AG, was elevated during the UVR exposure course (p < 0.05 vs. baseline for all subjects; p < 0.01 for each phototype group), with maximum levels reached by week 2-3, while NAE species did not significantly alter. These findings suggest differential involvement of the cutaneous endocannabinoid system in low dose solar UVR responses in humans.

Cannabinoid-induced increase of quantal size and enhanced neuromuscular transmission

Cannabinoids exert dynamic control over many physiological processes including memory formation, cognition and pain perception. In the central nervous system endocannabinoids mediate negative feedback of quantal transmitter release following postsynaptic depolarization. The influence of cannabinoids in the peripheral nervous system is less clear and might have broad implications for the therapeutic application of cannabinoids. We report a novel cannabinoid effect upon the mouse neuromuscular synapse: acutely increasing synaptic vesicle volume and raising the quantal amplitudes. In a mouse model of myasthenia gravis the cannabinoid receptor agonist WIN 55,212 reversed fatiguing failure of neuromuscular transmission, suggesting future therapeutic potential. Our data suggest an endogenous pathway by which cannabinoids might help to regulate transmitter release at the neuromuscular junction.

Psychobiological Responses to Aerobic Exercise in Individuals With Posttraumatic Stress Disorder

Previous reports have shown improvements in mood and increases in endocannabinoids in healthy adults following a session of aerobic exercise, but it is unclear whether adults with posttraumatic stress disorder (PTSD) experience similar responses. The purpose of this study was to examine psychobiological responses (plasma endocannabinoids [eCBs], mood, and pain) to aerobic exercise in a sample of adults with a diagnosis of PTSD (n = 12) and healthy controls (n = 12). Participants engaged in an aerobic exercise session in which they ran on a treadmill for 30 min at a moderate intensity (70 to 75% maximum heart rate [MHR]). Results indicated improvements in mood states and reductions in pain for both groups following exercise, ds = 0.19 to 1.53. Circulating concentrations of N-arachidonylethanolamine (AEA), 2-arachidonoylglycerol (2-AG), and oleoylethanolamide (OEA) significantly increased (ps = .000 to .050) following the aerobic exercise session for both groups. There were no significant time, group, or interaction effects (ps = .062 to .846) for palmitoylethanolamide (PEA) and 2-oleoylglycerol (2-OG). Although eCBs increased significantly for both groups, within-group effect size calculations indicated the healthy controls experienced a greater magnitude of change for AEA when compared with adults with PTSD, d = 1.21 and d = 0.45, respectively; as well as for 2-AG, d = 0.43 and d = 0.21, respectively. The findings from this study indicated that adults with and without PTSD reported significant mood improvements following 30 min of moderate-intensity aerobic exercise. In addition, the endocannabinoid system was activated in adults with and without PTSD, although effect sizes suggest that adults with PTSD may have a blunted endocannabinoid response to exercise.

Effect of exercise versus cognitive behavioural therapy or no intervention on anxiety, depression, fitness and quality of life in adults with previous methamphetamine dependency: a systematic review

BACKGROUND

Methamphetamine (MA) is a highly addictive psychostimulant used by approximately 52 million people worldwide. Chronic MA abuse leads to detrimental physiological and neurological changes, as well as increases in anxiety and depression, and decreases in overall fitness and quality of life. Exercise has been reported to possibly reverse physiological and neurological damage caused by previous MA use, and to reduce anxiety and depression in this population. The aim of this systematic review was to identify, clinically appraise and synthesise the available evidence for the effectiveness of exercise, compared to cognitive behavioural therapy (CBT), standard care or no intervention, on decreasing anxiety and depression and improving fitness and quality of life in previous MA users.

METHODS

Seven computerised databases were searched from inception to May 2017, namely Scopus, Cochrane Library, PubMed/MEDLINE, PEDro, CINAHL, and ScienceDirect. Search terms included exercise, methamphetamine, fitness measures, depression, anxiety and quality of life. Randomised and non-randomised controlled- or clinical trials and pilot studies, published in English, were considered for inclusion. Methodological quality was critically appraised according to the PEDro scale. Heterogeneity across studies regarding control groups and assessment intervals rendered meta analyses inappropriate for this review and results were thus described narratively using text and tables.

RESULTS

Two hundred and fifty-one titles were identified following the initial search, and 14 potentially-relevant titles were selected and the abstracts reviewed. Three studies (two randomised controlled trials and one quasi-experimental pilot) were included, with an average PEDro score of 6.66. Exercise resulted in significantly lower depression and anxiety scores versus CBT (p = 0.001). Balance also significantly improved following exercise versus standard care (p < 0.001); as did vital capacity, hand-grip and one-leg stand with eyes closed. There were significant changes in all subdivisions of the Quality of Life Scale Questionnaire (p < 0.05), except psychology (p = 0.227).

CONCLUSIONS

Level II evidence suggests that exercise is effective in reducing anxiety and depression and improving fitness in previous MA users, and Level III-2 evidence suggests that exercise is beneficial for improving quality of life in this population. Overall recovery in previous MA dependents might be significantly enhanced by including exercise in the rehabilitation process. Further research is required to strengthen these conclusions and to inform policy and health systems effectively.

Exercise Leads to Better Clinical Outcomes in Those Receiving Medication Plus Cognitive Behavioral Therapy for Major Depressive Disorder

OBJECTIVE

The aim of this study is to investigate the effects of exercise as an add-on therapy with antidepressant medication and cognitive behavioral group therapy (CBGT) on treatment outcomes in low-active major depressive disorder (MDD) patients. We also explored whether exercise reduces the residual symptoms of depression, notably cognitive impairment and poor sleep quality, and aimed to identify putative biochemical markers related to treatment response.

METHODS

Sixteen low-active MDD patients were recruited from a mental health day treatment program at a local hospital. Eight medicated patients performed an 8-week exercise intervention in addition to CBGT, and eight medicated patients attended the CBGT only. Twenty-two low-active, healthy participants with no history of mental health illness were also recruited to provide normal healthy values for comparison.

RESULTS

Results showed that exercise resulted in greater reduction in depression symptoms (p = 0.007, d = 2.06), with 75% of the patients showing either a therapeutic response or a complete remission of symptoms vs. 25% of those who did not exercise. In addition, exercise was associated with greater improvements in sleep quality (p = 0.046, d = 1.28) and cognitive function (p = 0.046, d = 1.08). The exercise group also had a significant increase in plasma brain-derived neurotrophic factor (BDNF), p = 0.003, d = 6.46, that was associated with improvements in depression scores (p = 0.002, R² = 0.50) and sleep quality (p = 0.011, R² = 0.38).

CONCLUSION

We provide evidence that exercise as an add-on to conventional antidepressant therapies improved the efficacy of standard treatment interventions. Our results suggest that plasma BDNF levels and sleep quality appear to be good indicators of treatment response and potential biomarkers associated with the clinical recovery of MDD.

Circulating Endocannabinoids: From Whence Do They Come and Where are They Going?

The goal of this review is to summarize studies in which concentrations of circulating endocannabinoids in humans have been examined in relationship to physiological measurements and pathological status. The roles of endocannabinoids in the regulation of energy intake and storage have been well studied and the data obtained consistently support the hypothesis that endocannabinoid signaling is associated with increased consumption and storage of energy. Physical exercise mobilizes endocannabinoids, which could contribute to refilling of energy stores and also to the analgesic and mood-elevating effects of exercise. Circulating concentrations of 2-arachidonoylglycerol are very significantly circadian and dysregulated when sleep is disrupted. Other conditions under which circulating endocannabinoids are altered include inflammation and pain. A second important role for endocannabinoid signaling is to restore homeostasis following stress. Circulating endocannabinoids are stress-responsive and there is evidence that their concentrations are altered in disorders associated with excessive stress, including post-traumatic stress disorder. Although determination of circulating endocannabinoids can provide important information about the state of endocannabinoid signaling and thus allow for hypotheses to be defined and tested, the large number of physiological factors that contribute to their circulating concentrations makes it difficult to use them in isolation as a biomarker for a specific disorder.

Endocannabinoids: Effectors of glucocorticoid signaling

For decades, there has been speculation regarding the interaction of cannabinoids with glucocorticoid systems. Given the functional redundancy between many of the physiological effects of glucocorticoids and cannabinoids, it was originally speculated that the biological mechanisms of cannabinoids were mediated by direct interactions with glucocorticoid systems. With the discovery of the endocannabinoid system, additional research demonstrated that it was actually the opposite; glucocorticoids recruit endocannabinoid signaling, and that the engagement of endocannabinoid signaling mediated many of the neurobiological and physiological effects of glucocorticoids. With the development of advances in pharmacology and genetics, significant advances in this area have been made, and it is now clear that functional interactions between these systems are critical for a wide array of physiological processes. The current review acts a comprehensive summary of the contemporary state of knowledge regarding the biological interactions between glucocorticoids and endocannabinoids, and their potential role in health and disease.

The Effect of Eight Weeks of Aerobic, Anaerobic and Resistance Training on some factor of Endocannabinoid System, Serotonin, Beta-Endorphin and BDNF in Young Men

ABSTRACT: The aim of this study was investigated the effect of eight weeks of aerobic, anaerobic and resistance training on some endocannabinoid, serotonin, beta-endorphin and BDNF agents of young men. Thirty-two young men (19 to 25 years old) who did not have regular physical activity were randomly divided into four groups, and each of them were participated in various sports exercises for eight weeks. A group for aerobic exercises (two exercises with 65-70 maximum heart rate 3 sessions per week), an anaerobic exercise group (two exercises with a maximum intensity of 3 sessions per week), a group for circular resistance exercises (6-8 Station Which is repeated 8-12 times, and for three times a week) and finally a group was selected as a control. ELISA method was used to measure endocannabinoid system, serotonin, beta-endorphin and BDNF factors. The results showed that eight weeks aerobic training significantly increased serotonin levels and eight weeks aerobic and anaerobic exercise significantly increased BDNF. Aerobic, anaerobic, and resistive exercises have no significant effect on arachidonoyl glycerol (2-AG), anandamide(AEA) and beta-endorphin. There was a significant increase in happiness in all three training groups compared to the control group.The results of this study indicated an increase in mediation associated with pleasure and happiness in humans. Concerning the particular effect of long-term exercise on the endocannabinoid system, it is difficult to conclude.

Exercise and mental health

There is a growing body of literature that recognizes the positive effects of exercise on mood states such as anxiety, stress and depression, through physiological and biochemical mechanisms, including endorphins, mitochondria, mammalian target of rapamycin, neurotransmitters and the hypothalamic-pituitary-adrenal axis, and via the thermogenic hypothesis. In addition, psychological mechanisms influence the effects of exercise on mood states, as suggested by both the distraction hypothesis and the self-efficacy hypothesis. Exercise has also been shown to reduce inflammation via several different processes (inflammation, cytokines, toll-like receptors, adipose tissue and via the vagal tone), which can contribute to better health outcomes in people suffering from mood disorders.

TRPV1 channels in human skeletal muscle feed arteries: implications for vascular function

NEW FINDINGS

What is the central question of this study? We sought to determine whether human skeletal muscle feed arteries (SFMAs) express TRPV₁ channels and what role they play in modulating vascular function. What is the main finding and its importance? Human SMFAs do express functional TRPV₁ channels that modulate vascular function, specifically opposing α-adrenergic receptor-mediated vasocontraction and potentiating vasorelaxation, in an endothelium-dependent manner, as evidenced by the α₁ -receptor-mediated responses. Thus, the vasodilatory role of TRPV₁ channels, and their ligand capsaicin, could be a potential therapeutic target for improving vascular function. Additionally, given the 'sympatholytic' effect of TRPV₁ activation and known endogenous activators (anandamide, reactive oxygen species, H⁺ , etc.), TRPV₁ channels might contribute to functional sympatholysis during exercise. To examine the role of the transient receptor potential vanilloid type 1 (TRPV₁ ) ion channel in the vascular function of human skeletal muscle feed arteries (SMFAs) and whether activation of this heat-sensitive receptor could be involved in modulating vascular function, SMFAs from 16 humans (63 ± 5 years old, range 41-89 years) were studied using wire myography with capsaicin (TRPV₁ agonist) and without (control). Specifically, phenylephrine (α₁ -adrenergic receptor agonist), dexmedetomidine (α₂ -adrenergic receptor agonist), ACh and sodium nitroprusside concentration-response curves were established to assess the role of TRPV₁ channels in α-receptor-mediated vasocontraction as well as endothelium-dependent and -independent vasorelaxation, respectively. Compared with control conditions, capsaicin significantly attenuated maximal vasocontraction in response to phenylephrine [control, 52 ± 8% length-tension_max (LT_max ) and capsaicin, 21 ± 5%LT_max ] and dexmedetomidine (control, 29 ± 12%LT_max and capsaicin, 2 ± 3%LT_max ), while robustly enhancing maximal vasorelaxation with ACh (control, 78 ± 8% vasorelaxation and capsaicin, 108 ± 13% vasorelaxation) and less clearly enhancing the sodium nitroprusside response. Denudation of the endothelium greatly attenuated the maximal ACh-induced vasorelaxation equally in the control and capsaicin conditions (∼17% vasorelaxation) and abolished the attenuating effect of capsaicin on the maximal phenylephrine response (denuded + capsaicin, 61 ± 20%LT_max ). Immunohistochemistry identified a relatively high density of TRPV₁ channels in the endothelium compared with the smooth muscle of the SMFAs, but because of the far greater volume of smooth muscle, total TRPV₁ protein content was not significantly attenuated by denudation. Thus, SMFAs ubiquitously express functional TRPV₁ channels, which alter vascular function, in terms of α₁ -receptors, in a predominantly endothelium-dependent manner, conceivably contributing to the functional sympatholysis and unveiling a therapeutic target.