Serotonin and motivation

BACKGROUND: The neurotoxicity of 3,4-methylenedioxy-methamphetamine (MDMA) to the serotonergic system is well-documented. Dextromethorphan (DM), an antitussive drug, decreased morphine- or methamphetamine (MA)-induced reward in rats and may prevent MDMA-induced serotonergic deficiency in primates, as indicated by increased serotonin transporter (SERT) availability. We aimed to investigate the effects of DM on reward, behavioral sensitization, and neurotoxicity associated with loss of SERT induced by chronic MDMA administration in rats...

Day length, or photoperiod, is a reliable environmental cue encoded by the brain's circadian clock that indicates changing seasons and induces seasonal biological processes. In humans, photoperiod, age, and sex have been linked to seasonality in neuropsychiatric disorders, as seen in Seasonal Affective Disorder, Major Depressive Disorder, and Bipolar Disorder. The nucleus accumbens is a key locus for the regulation of motivated behaviors and neuropsychiatric disorders. Using periadolescent and young adult male and female mice, here we assessed photoperiod's effect on serotonin and dopamine tissue content in the nucleus accumbens core, as well as on accumbal synaptic dopamine release and uptake...

BACKGROUND: The proliferation of Novel Psychoactive Substances (NPS) in the drug market raises concerns about uncertainty on their pharmacological profile and the health hazard linked to their use. Within the category of synthetic stimulant NPS, the phenethylamine 2-Cl-4,5-methylenedioxymethamphetamine (2-Cl-4,5-MDMA) has been linked to severe intoxication requiring hospitalization. Thereby, the characterization of its pharmacological profile is urgently warranted. METHODS: By in vivo brain microdialysis in adolescent and adult male rats we investigated the effects of 2-Cl-4,5-MDMA on dopamine (DA) and serotonin (5-HT) neurotransmission in two brain areas critical for the motivational and reinforcing properties of drugs, the nucleus accumbens (NAc) shell and the medial prefrontal cortex (mPFC)...

The intensification of production systems has resulted in detrimental effects on sow welfare, which can have an adverse influence on their offspring. Considering the relevance of the microbiota-gut-brain axis, probiotics can mitigate such impacts. To investigate the effects of the dietary inclusion of probiotics on the welfare of sows and piglets, 147 multiparous sows were randomly assigned to two groups: a control group or a group supplemented with a multistrain probiotic from the beginning of pregnancy to the end of lactation...

We have recently shown that experience of flight remarkably enhanced subsequent terrestrial phonotaxis in females in response to the male calling song. Here, we elucidated the possible roles of octopamine and serotonin in the enhancing effect of flying on phonotactic behavior. Octopamine is known to be released into the hemolymph during flight in insects; however, the octopamine receptor antagonist epinastine did not abolish the effects of flight in our study. On the contrary, the drug significantly potentiated the influence of flying on phonotactic behavior...

Anhedonia is clinically defined as difficulty or inability to feel pleasure or to be motivated to perform activities that were previously pleasurable. Anhedonia is a core feature of depressive disorders but can be present in other conditions such as substance use and anxiety disorders. Herein we report the case of a 34-year-old female who developed marked anhedonia after left cortico-amygdalohippocampectomy. Despite optimal seizure control, the person struggled with anhedonia and other depressive symptoms. After ruling out medico-neurologic complications, she was prescribed with a selective serotonin reuptake inhibitor and cognitive-behavioral therapy...

Stress is a complex and multifaceted phenomenon that can significantly influence both aggressive behavior and sexual function. This review explores the intricate relationship between stress, neuromodulator pathways, and epigenetics, shedding light on the various mechanisms that underlie these connections. While the role of stress in both aggression and sexual behavior is well-documented, the mechanisms through which it exerts its effects are multifarious and not yet fully understood. The review begins by delving into the potential influence of stress on the Hypothalamic-Pituitary-Adrenal (HPA) axis, glucocorticoids, and the neuromodulators involved in the stress response...

BACKGROUND: After the Coronavirus Disease pandemic, depression became more present, including in adolescents. Escitalopram, a selective serotonin reuptake inhibitor, was approved in 2009 for treatment of the major depressive disorder, both in children and adolescents. The undesirable effects of antidepressants on sexual dysfunction are usually underestimated. AIMS: To investigate the effects of chronic mild stress, induced from peripuberty up to adulthood, on male sexual behavior parameters, with or without the escitalopram treatment, using rats as experimental model in a translational study...

Schizophrenia, a global mental health disorder affecting approximately 1 % of the population, is characterized by neurotransmitter dysregulation, particularly dopamine, serotonin, and glutamate. Current antipsychotic therapies, despite their efficacy, are accompanied by adverse effects, which has motivated researchers to investigate more secure substitutes. This study examines the potential antipsychotic effects of esculetin, a natural coumarin derivative recognized for its wide-ranging pharmacological activities (anti-inflammatory, antioxidant, anti-pathogenic, anticancer, and neuroprotective), in animal model of schizophrenia induced by ketamine...

RBFOX1 functions as a master regulator of thousands of genes, exerting a pleiotropic effect on numerous neurodevelopmental and psychiatric disorders. A potential mechanism by which RBFOX1 may impact these disorders is through its modulation of serotonergic neurotransmission, a common target for pharmacological intervention in psychiatric conditions linked to RBFOX1 . However, the precise effects of RBFOX1 on the serotonergic system remain largely unexplored. Here we show that homozygous rbfox1sa15940 zebrafish, which express a shorter, aberrant rbfox1 mRNA, have significantly reduced serotonin levels in telencephalon and diencephalon...

Apathy is a common and disabling complication of Parkinson's disease characterised by reduced goal-directed behaviour. Several studies have reported dysfunction within prefrontal cortical regions and projections from brainstem nuclei whose neuromodulators include dopamine, serotonin and noradrenaline. Work in animal and human neuroscience have confirmed contributions of these neuromodulators on aspects of motivated decision making. Specifically, these neuromodulators have overlapping contributions to encoding the value of decisions, and influence whether to explore alternative courses of action, or persist in an existing strategy to achieve a rewarding goal...

Adolescent-onset depression is a prevalent and debilitating condition commonly associated with treatment refractory depression and non-response to first-line antidepressants. There are, however, no objective tests to determine who may or may not respond to antidepressants. As depressed adolescents are especially vulnerable to the lifelong consequences of ineffectively-treated depression, it is critical to identify neurobiological predictors of treatment non-response in this population. Here, we describe the scientific rationale and protocol for the Teen Inflammation Glutamate Emotion Research (TIGER) study, a prospective 18-month investigation of 160 depressed adolescents who will be assessed before and after treatment with selective serotonin reuptake inhibitors...

Serotonin (5-HT) deficiency is a core biological pathology underlying depression and other psychiatric disorders whose key symptoms include decreased motivation. However, the exact role of 5-HT in motivation remains controversial and elusive. Here, we pharmacologically manipulated the 5-HT system in macaque monkeys and quantified the effects on motivation for goal-directed actions in terms of incentives and costs. Reversible inhibition of 5-HT synthesis increased errors and reaction times on goal-directed tasks, indicating reduced motivation...

Anxiety and anxiety disorders are important modifiable risk factors for cardiovascular and other common chronic non-communicable diseases and complications. Anxiety disorders significantly reduce the motivation and adherence of patients to lifestyle changes and drug therapy, significantly worsen the quality of life, and increase the risk of disability and the costs of the health care system. The issues of diagnosis and therapy of anxiety are relevant for the practice of physicians and cardiologists due to the high incidence of anxiety disorders in patients with cardiovascular diseases, a decrease in the quality of life and an increase in adverse outcomes, and also due to the insufficient awareness of the risks associated with the psycho-emotional state of patients...

OBJECTIVE: Aim: Conduct a comparative analysis of effectiveness of obesity treatment in primary care using patient-oriented approach with motivational counseling for lifestyle correction and its combination with armodafinil therapy in patients with concomitant shift work sleep disorder. PATIENTS AND METHODS: Materials and Methods: 75 patients with obesity were studied, 38 patients had shift work disorder. Patients were divided into 2 groups: I (37 patients with obesity treated with motivational counseling) and II (38 patients with obesity and shift work disorder treated additionally with armodafinil 150 mg daily)...

Methylphenidate (MPD), known as Ritalin, is a psychostimulant used to treat children, adults, and the elderly. MPD exerts its effects through increasing concentrations of dopamine (DA), norepinephrine (NE), and serotonin (5-HT) in the synaptic cleft. Concomitant behavioral and neuronal recording from the ventral tegmental area (VTA), locus coeruleus (LC), and from the dorsal raphe (DR) nucleus, which are the sources of DA, NE, and 5-HT to the mesocorticolimbic circuit, were investigated following acute and repetitive (chronic) saline, 0...

BACKGROUND: Perinatal depression is a mental health disorder that is associated with feelings of hopelessness, despair, and lack of motivation. Its effects on pregnant women are not limited to hemorrhage and hypertension and may lead to maternal mortality. As a result, maternal antidepressant usage during pregnancy has rapidly increased in the United States. Selective serotonin reuptake inhibitors (SSRIs) are considered one of the most prescribed antidepressants. Thus, this study aims to measure the prevalence of SSRI use during pregnancy...

BACKGROUND AND OBJECTIVES: The renewed interest in psychedelic research provides growing evidence of potentially unique effects on various aspects of reward processing systems. Using the Research Domain Criteria (RDoC) framework, as proposed by the National Institute of Mental Health, we aim to synthesize the existing literature concerning the impact of lysergic acid diethylamide (LSD) on the RDoC's Positive Valence Systems (PVS) domain, and to identify potential avenues for further research...

OBJECTIVE: To evaluate the clinical efficacy and safety of Agomelatine in improving symptoms in patients with major depressive disorder (MDD), providing more scientific evidence for the treatment of depression, and offering more effective therapeutic options for patients. METHODS: A total of 180 MDD patients in acute phase from 10 psychiatric hospitals of Grade three in Zhejiang Province were enrolled in this 12-week study with the competitive and consecutive pattern, and they were randomized into two different groups treated with flexible-dosage antidepressants of selective serotonin reuptake inhibitors (SSRI) or agomelatine, respectively...

The serotonin 5HT2c receptor has been widely implicated in the pathophysiology of alcohol use disorder (AUD), particularly alcohol seeking and the affective consequences of chronic alcohol consumption. However, little is known about the brain sites in which 5HT2c exerts its effects on specific alcohol-related behaviors, especially in females. Here, we investigated the effects of site-specific manipulation of the 5HT2c receptor system in the BNST on operant alcohol self-administration behaviors in adult mice of both sexes, including the acquisition and maintenance of fixed-ratio responding, motivation for alcohol (progressive ratio), and quinine-adulterated responding for alcohol on a fixed-ratio schedule (punished alcohol seeking)...