Autism Spectrum Disorder (ASD) refers to a group of neurodevelopmental disorders including autism, Asperger's syndrome (AS) and pervasive developmental disorder-not otherwise specified (PDD-NOS). The ...new diagnostic criteria of ASD focuses on two core domains: social communication impairment and restricted interests/repetitive behaviors. The prevalence of ASD has been steadily increasing over the past two decades, with current estimates reaching up to 1 in 36 children. Hereditary factors, parental history of psychiatric disorders, pre-term births, and fetal exposure to psychotropic drugs or insecticides have all been linked to higher risk of ASD. Several scales such as the Childhood Autism Rating Scale (CARS), The Autism Spectrum Disorder–Observation for Children (ASD-OC), The Developmental, Dimensional, and Diagnostic Interview (3di), are available to aid in better assessing the behaviors and symptoms associated with ASD. Nearly 75% of ASD patients suffer from comorbid psychiatric illnesses or conditions, which may include attention-deficit hyperactivity disorder (ADHD), anxiety, bipolar disorder, depression, Tourette syndrome, and others. Both pharmacological and non-pharmacological interventions are available for ASD. Pharmacological treatments include psychostimulants, atypical antipsychotics, antidepressants, and alpha-2 adrenergic receptor agonists. These medications provide partial symptomatic relief of core symptoms of ASD or manage the symptoms of comorbid conditions. Non-pharmacological interventions, which show promising evidence in improving social interaction and verbal communication of ASD patients, include music therapy, cognitive behavioral therapy and social behavioral therapy. Hormonal therapies with oxytocyin or vasopressin receptor antagonists have also shown some promise in improving core ASD symptoms. The use of vitamins, herbal remedies and nutritional supplements in conjunction with pharmacological and behavioral treatment appear to have some effect in symptomatic improvement in ASD, though additional studies are needed to confirm these benefits. Developing novel disease-modifying therapies may prove to be the ultimate intervention for sustained improvement of symptoms in ASD.
Treatment of major depressive disorder (MDD) including treatment-resistant depression (TRD) remains a major unmet need. Although there are several classes of dissimilar antidepressant drugs approved ...for MDD, the current drugs have either limited efficacy or are associated with undesirable side effects and withdrawal symptoms. The efficacy and side effects of antidepressant drugs are mainly attributed to their actions on different monoamine neurotransmitters (serotonin, norepinephrine, and dopamine). Development of new antidepressants with novel targets beyond the monoamine pathways may fill the unmet need in treatment of MDD and TRD. The recent approval of intranasal Esketamine (glutamatergic agent) in conjunction with an oral antidepressant for the treatment of adult TRD patients was the first step toward expanding beyond the monoamine targets. Several other glutamatergic (AXS-05, REL-1017, AV-101, SLS-002, AGN24175, and PCN-101) and GABAergic (brexanolone, zuranolone, and ganaxolone) drugs are currently in different stages of clinical development for MDD, TRD and other indications. The renaissance of psychedelic drugs and the emergence of preliminary positive clinical trial results with psilocybin, Ayahuasca, 5-methoxy-
-dimethyltryptamine (5-MeO-DMT), and lysergic acid diethylamide (LSD) may pave the way towards establishing this class of drugs as effective therapies for MDD, TRD and other neuropsychiatric disorders. Going beyond the monoamine targets appears to be an effective strategy to develop novel antidepressant drugs with superior efficacy, safety, and tolerability for the improved treatment of MDD and TRD.
Oxytocin (OT) is a neurohypophysial hormone and neuropeptide produced by the hypothalamus and released by the pituitary gland. It has multiple physiological roles including stimulation of parturition ...and lactation, and promotion of pro-adaptive social behaviors necessary for mammalian survival. OT interacts with one receptor subtype: the OT receptor (OTR) which, upon stimulation, triggers different intracellular signal transduction cascades to mediate its physiological actions. Preclinical studies show that OT regulates social behaviors such as pair bonding, recognition and social interaction. It also coordinates the activation of the hypothalamic–pituitary–adrenal (HPA) axis and the release of corticotrophin-releasing hormone. Further evidence suggests that OT plays an important role in regulating caloric intake and metabolism, and in maintaining electrolyte and cardiovascular homeostasis. OT is also involved in attenuating the neurophysiological and neurochemical effects of trauma on the brain and body by facilitating both physical attachment such as wound healing, and psychological/social attachment, thereby increasing resilience to subsequent traumatic events. Clinical trials have reported that intranasal administration of OT provides therapeutic benefits for patients diagnosed with traumatic stress-related diseases such as major depressive disorders and post-traumatic stress disorder. OT’s therapeutic benefits may result from context-dependent interactions with key neural pathways (social, cognitive, and reward), neurotransmitters (dopamine, norepinephrine, serotonin, and endogenous opioids), and biomarkers (adrenocorticotropic hormone, cortisol, and dehydroepiandrosterone sulfate), that lead to a decrease in stress -associated behaviors, and facilitate post-traumatic growth, ultimately leading to increased resilience, through improved social cohesion and attachment. OT induced-augmentation of physical and cognitive resilience may play a significant role in both the prevention of, and improved clinical outcomes for, traumatic stress-related disorders following either acute or enduring traumatic experiences.
Alzheimer's disease (AD) is the most common cause of memory impairment and dementia in the elderly. AD is pathologically characterized by extracellular deposits of beta-amyloid (Aβ) peptide, ...neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau, neuronal loss, and neurotransmitter dysfunction. Clinically, AD is characterized by progressive cognitive decline that usually starts with memory impairment and progresses to cause a more generalized cognitive dysfunction, behavioral dysregulation, and neuropsychiatric symptoms. These symptoms collectively lead to a progressive and relentless decline in the ability to perform functions of daily living, eventually leading to total incapacitation. The incidence and prevalence of AD are expected to exponentially increase with the aging of the population. Currently approved treatments, including the acetylcholinesterase inhibitors (AChEIs) donepezil, galantamine and rivastigmine, and the N-methyl-D-aspartate (NMDA) antagonist memantine, do not halt the progression of the disease, and have provided marginal therapeutic benefits. Accordingly, there is an urgent need to develop novel and effective medications for AD that go beyond AChEIs and NMDA antagonists. Modern research has focused on discovering effective disease-modifying therapies, which specifically target the pathophysiologic cascade, hoping to delay the onset of the disease and slow its progression. In this review, different pharmacological drugs and therapeutic approaches will be discussed, with an emphasis on novel therapies that are currently being investigated in clinical trials.
Vortioxetine is a novel antidepressant drug approved for the treatment of major depressive disorder (MDD) in adults. It is formulated into tablets and has a dose range of 5-20 mg. The recommended ...starting dose is 10 mg administered orally once daily without the need for food. Areas covered: This review focuses on the preclinical and clinical discovery of vortioxetine. It analyzes the pharmacological, neurochemical, and behavioral mechanisms of the medication and how these contribute to its potential therapeutic advantages as described in published preclinical and clinical studies and product labels. Expert opinion: Vortioxetine displays high affinity for serotonin transporter (SERT), and serotonin 5-HT
, 5HT
, 5HT
receptors. Functional studies show that vortioxetine acts as a SERT blocker, a 5-HT
, 5-HT
receptor antagonist, and a 5-HT
receptor agonist. The drug is active in animal models predictive of antipsychotic and antidepressant activities and demonstrates procognitive effects in several animal models that assessed memory, cognition, and executive functions. Short- and long-term clinical trials demonstrated the clinical efficacy of vortioxetine in treating depressive symptoms and cognitive deficits in MDD patients. It also displays fairly benign safety and tolerability profiles. Vortioxetine's unique psychopharmacological properties might contribute to an improved clinical outcome in MDD patient populations.
Overwhelming research evidence suggests that the negative symptoms of schizophrenia (NSS) contribute more to impaired quality of life and poor functioning than positive symptoms, and that NSS, ...including affective flattening, alogia and avolition are present in at least one-fifth of patients diagnosed with schizophrenia. Despite this, management of NSS continues to be a major clinical unmet need as treatment with current antipsychotic medication seems to reach at best modest efficacy. A critical review of the current pharmacological, non-pharmacological and psychosocial treatments available for NSS is presented here, using data retrieved from the MEDLINE/PUBMED, the Cochrane Database of Systematic Reviews and the ClinicalTrials.gov databases. An early and accurate diagnosis using selective scales is essential for documentation and monitoring of change in NSS according to treatment response. Typical and atypical antipsychotic drugs, showed modest efficacy in managing NSS. Conflicting results were obtained with the use of glycinergic neuromodulators, anticholinergics, antidepressants, anticonvulsants, psychostimulants, modafinil and 5-HT3 receptor antagonists. Moreover, non-pharmacological therapies including psychological therapies have failed to address NSS effectively. At present, it appears that the best effective approach for clinical management of NSS is achieved by complementing drug therapy with psychosocial therapies. Continuing basic and clinical research for the understanding of the genetic, behavioral and neural basis of NSS should yield novel pharmacotherapies with superior efficacy, tolerability and long-term maintenance for improved treatment of NSS.
Major depressive disorder is a serious neuropsychiatric disease that leads to significant impairment in social functioning and increased morbidity and mortality. Low vitamin D (25-OH D) levels have ...been hypothesized to contribute to the pathophysiology of MDD. To investigate the therapeutic role of vitamin D in MDD, we recruited 62 male and female patients diagnosed with MDD and randomized them into two groups: the first group (49 patients) received vitamin D supplementation as cholecalciferol vitamin D
3
(50,000 I.U.) for 3 months, in addition to standard of care (SOC) which included pharmacological treatment and psychological support, and the second group (13 patients) received only SOC without vitamin D supplementation for 3 months. The Beck depression inventory (BDI) scale was used to assess the severity of MDD symptoms. Immunoassays were utilized to determine levels of serum vitamin D
3
and serotonin in all patients. The results showed significant gender differences; female patients showed the most improvement in their depressive symptoms after 3-month vitamin D supplementation. Females with moderate, severe, and extreme depression had significantly lower BDI scores after vitamin D treatment (
p
< 0.05). Among males, only those diagnosed with severe depression showed significant improvement in their BDI scores (
p
< 0.05). Serum serotonin levels were significantly increased after vitamin D supplementation compared to baseline in both male and female patients. No significant changes in other biochemical parameters were detected between the two groups. These findings suggest that vitamin D supplementation may ameliorate symptoms of MDD, particularly in females, via a serotonin-dependent mechanism.
Approximately 1 in 36 children are diagnosed with autism spectrum disorder (ASD). The disorder is four times more common in males than in females. Zinc deficiency and mutations in SHANK2 and SHANK3 ...(members of a family of excitatory postsynaptic scaffolding proteins) are all risk factors that may contribute to the pathophysiology of the disease. The presence of shankopathies (loss of one copy of the SHANK3 gene) can lead to the development of Phelan‐McDermid syndrome (PMDS)—a rare genetic disorder characterized by developmental delay, intellectual disability, poor motor tone, and ASD‐like symptoms. We reviewed the relationship between zinc, ASD, and PMDS as well as the effect of zinc supplementation in improving symptoms of ASD and PMDS based on 22 studies published within 6 years (2015–2020). Zinc deficiency (assessed by either dietary intake, blood, hair, or tooth matrix) was shown to be highly prevalent in ASD and PMDS patients as well as in preclinical models of ASD and PMDS. Zinc supplements improved the behavioral deficits in animal models of ASD and PMDS. Clinical trials are still needed to validate the beneficial therapeutic effects of zinc supplements in ASD and PMDS patients.
Introduction: Major depressive disorder (MDD) is the leading cause of disability worldwide, and according to the STAR*D trial, only 33% of patients with MDD responded to initial drug therapy. ...Augmentation of the leading class of antidepressant treatment, selective serotonin reuptake inhibitors (SSRIs), with the 5-HT
1A
receptor agonist buspirone has been shown to be effective in treating patients that do not respond to initial SSRI therapy. This suggests that newer treatments may improve the clinical picture of MDD. The US Food and Drug Administration (FDA) approved the antidepressant drug vilazodone (EMD 68843), a novel SSRI and 5-HT
1A
receptor partial agonist. Vilazodone has a half-life between 20-24 hours, reaches peak plasma concentrations at 3.7-5.3 hours, and is primarily metabolized by the hepatic CYP450 3A4 enzyme system.
Areas covered: The authors review the preclinical and clinical profile of vilazodone. The roles of serotonin, the 5-HT
1A
receptor, and current pharmacotherapy approaches for MDD are briefly reviewed. Next, the preclinical pharmacological, behavioral, and physiological effects of vilazodone are presented, followed by the pharmacokinetic properties and metabolism of vilazodone in humans. Last, a brief summary of the main efficacy, safety, and tolerability outcomes of clinical trials of vilazodone is provided.
Expert opinion: Vilazodone has shown efficacy versus placebo in improving depression symptoms in several double-blind, placebo-controlled trials. The long-term safety and tolerability of vilazodone treatment has also been established. Further studies are needed that directly compare patients treated with an SSRI (both with and without an adjunctive 5-HT1A partial agonist) versus patients treated with vilaozodone.
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