Potential of cannabinoids as treatments for autism spectrum disorders

The Evolving Role of Cannabidiol-Rich Cannabis in People with Autism Spectrum Disorder: A Systematic Review

Autism spectrum disorder (ASD) is a neurological disease and lifelong condition. The treatment gap in ASD has led to growing interest in alternative therapies, particularly in phytocannabinoids, which are naturally present in Cannabis sativa. Studies indicate that treatment with cannabidiol (CBD)-rich cannabis may possess the potential to improve fundamental ASD symptoms as well as comorbid symptoms. This systematic review aims to assess the safety and efficacy of CBD-rich cannabis in alleviating the symptoms of ASD in both children and adults, addressing the treatment gap and growing interest in CBD as an alternative treatment. A comprehensive literature search was conducted in February 2024 using the PUBMED and Scopus databases while following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search focused on studies from 2020 onward involving human populations diagnosed with ASD and treated with CBD. Four studies met the inclusion criteria and were analyzed. The review included 353 participants with ASD from studies conducted in Israel, Turkey, and Brazil. The studies varied in design, sample size, dose, and treatment duration. Dosages of CBD were often combined with trace amounts of THC. Improvements were noted in behavioral symptoms, social responsiveness, and communication, but cognitive benefits were less consistent. Adverse effects ranged in severity. Mild effects such as somnolence and decreased appetite were common, while more concerning effects, including increased aggression, led to some cases of treatment discontinuation. CBD-rich cannabis shows promise in improving behavioral symptoms associated with ASD. However, variations in study designs, dosages, and outcome measures highlight the need for standardized assessment tools and further research to understand pharmacological interactions and optimize treatment protocols. Despite the mild adverse effects observed, larger, well-controlled trials are necessary to establish comprehensive safety and efficacy profiles.

Cannabis Pharmacogenomics: A Path to Personalized Medicine

Cannabis and related compounds have created significant research interest as a promising therapy in many disorders. However, the individual therapeutic effects of cannabinoids and the incidence of side effects are still difficult to determine. Pharmacogenomics may provide the answers to many questions and concerns regarding the cannabis/cannabinoid treatment and help us to understand the variability in individual responses and associated risks. Pharmacogenomics research has made meaningful progress in identifying genetic variations that play a critical role in interpatient variability in response to cannabis. This review classifies the current knowledge of pharmacogenomics associated with medical marijuana and related compounds and can assist in improving the outcomes of cannabinoid therapy and to minimize the adverse effects of cannabis use. Specific examples of pharmacogenomics informing pharmacotherapy as a path to personalized medicine are discussed.

Implications of the endocannabinoid system and the therapeutic action of cannabinoids in autism spectrum disorder: A literature review

Autism spectrum disorder (ASD) is a neurodevelopmental disorder, onset in early childhood and associated with cognitive, social, behavioral, and sensory impairments. The pathophysiology is still unclear, and it is believed that genetic and environmental factors are fully capable of influencing ASD, especially cell signaling and microglial functions. Furthermore, the endocannabinoid system (ECS) participates in the modulation of various brain processes and is also involved in the pathophysiological mechanisms of this condition. Due to the health and quality of life impacts of autism for the patient and his/her family and the lack of effective medications, the literature has elucidated the possibility that Cannabis phytocannabinoids act favorably on ASD symptoms, probably through the modulation of neurotransmitters, in addition to endogenous ligands derived from arachidonic acid, metabolizing enzymes and even transporters of the membrane. These findings support the notion that there are links between key features of ASD and ECS due to the favorable actions of cannabidiol (CBD) and other cannabinoids on symptoms related to behavioral and cognitive disorders, as well as deficits in communication and social interaction, hyperactivity, anxiety and sleep disorders. Thus, phytocannabinoids emerge as therapeutic alternatives for ASD.

Children and adolescents with ASD treated with CBD-rich cannabis exhibit significant improvements particularly in social symptoms: an open label study

In recent years there has been growing interest in the potential benefits of CBD-rich cannabis treatment for children with ASD. Several open label studies and one double-blind placebo-controlled study have reported that CBD-rich cannabis is safe and potentially effective in reducing disruptive behaviors and improving social communication. However, previous studies have mostly based their conclusions on parental reports without the use of standardized clinical assessments. Here, we conducted an open label study to examine the efficacy of 6 months of CBD-rich cannabis treatment in children and adolescents with ASD. Longitudinal changes in social communication abilities and restricted and repetitive behaviors (RRB) were quantified using parent report with the Social Responsiveness Scale and clinical assessment with the Autism Diagnostic Observation Schedule (ADOS). We also quantified changes in adaptive behaviors using the Vineland, and cognitive abilities using an age-appropriate Wechsler test. Eighty-two of the 110 recruited participants completed the 6-month treatment protocol. While some participants did not exhibit any improvement in symptoms, there were overall significant improvements in social communication abilities as quantified by the ADOS, SRS, and Vineland with larger improvements in participants who had more severe initial symptoms. Significant improvements in RRB were noted only with parent-reported SRS scores and there were no significant changes in cognitive scores. These findings suggest that treatment with CBD-rich cannabis can yield improvements, particularly in social communication abilities, which were visible even when using standardized clinical assessments. Additional double-blind placebo-controlled studies utilizing standardized assessments are highly warranted for substantiating these findings.

Lipid-Based Molecules on Signaling Pathways in Autism Spectrum Disorder

The signaling pathways associated with lipid metabolism contribute to the pathophysiology of autism spectrum disorder (ASD) and provide insights for devising new therapeutic strategies. Prostaglandin E2 is a membrane-derived lipid molecule that contributes to developing ASD associated with canonical Wnt signaling. Cyclooxygenase-2 plays a key role in neuroinflammation and is implicated in the pathogenesis of neurodevelopmental diseases, such as ASD. The endocannabinoid system maintains a balance between inflammatory and redox status and synaptic plasticity and is a potential target for ASD pathophysiology. Redox signaling refers to specific and usually reversible oxidation–reduction reactions, some of which are also involved in pathways accounting for the abnormal behavior observed in ASD. Redox signaling and redox status-sensitive transcription factors contribute to the pathophysiology of ASD. Cannabinoids regulate the redox balance by altering the levels and activity of antioxidant molecules via ROS-producing NADPH oxidase (NOX) and ROS-scavenging superoxide dismutase enzymes. These signaling cascades integrate a broad range of neurodevelopmental processes that may be involved in the pathophysiology of ASD. Based on these pathways, we highlight putative targets that may be used for devising novel therapeutic interventions for ASD.

Role of Brain Modulators in Neurodevelopment: Focus on Autism Spectrum Disorder and Associated Comorbidities

Autism spectrum disorder (ASD) and associated neurodevelopmental disorders share similar pathogenesis and clinical features. Pathophysiological changes in these diseases are rooted in early neuronal stem cells in the uterus. Several genetic and environmental factors potentially perturb neurogenesis and synaptogenesis processes causing incomplete or altered maturation of the brain that precedes the symptomology later in life. In this review, the impact of several endogenous neuromodulators and pharmacological agents on the foetus during pregnancy, manifested on numerous aspects of neurodevelopment is discussed. Within this context, some possible insults that may alter these modulators and therefore alter their role in neurodevelopment are high-lighted. Sometimes, a particular insult could influence several neuromodulator systems as is supported by recent research in the field of ASD and associated disorders. Dopaminergic hy-pothesis prevailed on the table for discussion of the pathogenesis of schizophrenia (SCH), atten-tion-deficit hyperactivity disorder (ADHD) and ASD for a long time. However, recent cumulative evidence suggests otherwise. Indeed, the neuromodulators that are dysregulated in ASD and comorbid disorders are as diverse as the causes and symptoms of this disease. Additionally, these neuromodulators have roles in brain development, further complicating their involvement in comorbidity. This review will survey the current understanding of the neuromodulating systems to serve the pharmacological field during pregnancy and to minimize drug-related insults in pa-tients with ASD and associated comorbidity disorders, e.g., SCH or ADHD.

Repetitive Restricted Behaviors in Autism Spectrum Disorder: From Mechanism to Development of Therapeutics

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder characterized by deficits in social communication, social interaction, and repetitive restricted behaviors (RRBs). It is usually detected in early childhood. RRBs are behavioral patterns characterized by repetition, inflexibility, invariance, inappropriateness, and frequent lack of obvious function or specific purpose. To date, the classification of RRBs is contentious. Understanding the potential mechanisms of RRBs in children with ASD, such as neural connectivity disorders and abnormal immune functions, will contribute to finding new therapeutic targets. Although behavioral intervention remains the most effective and safe strategy for RRBs treatment, some promising drugs and new treatment options (e.g., supplementary and cell therapy) have shown positive effects on RRBs in recent studies. In this review, we summarize the latest advances of RRBs from mechanistic to therapeutic approaches and propose potential future directions in research on RRBs.