Cannabinoids and cognition in Parkinson’s disease: Insights from animal models and emerging clinical evidence

“Parkinson’s disease (PD) is a progressive, multisystem neurodegenerative disorder characterized not only by motor impairments but also by a broad spectrum of debilitating non-motor symptoms, including cognitive decline. The cognitive function depends on neuronal plasticity, which is tightly regulated by multiple signaling systems, among which the endocannabinoid system (ECS) plays a significant role.

Over the past three decades, substantial evidence has accumulated regarding how endogenous cannabinoids, plant-derived cannabinoids, and pharmacological modulators of ECS signaling influence synaptic plasticity, neuronal excitability, and neuroinflammation – processes that are critical in PD pathophysiology.

This narrative review synthesizes experimental and clinical evidence on the effects of cannabinoid compounds on cognition in preclinical PD models and patients. Available clinical data are limited, heterogeneous, and often underpowered, with cognition frequently assessed as a secondary outcome. Observed variability in cognitive effects likely reflects differences in cannabinoid formulation, dose and treatment duration, study design, patient characteristics, and the use of heterogeneous cognitive endpoints across studies.

Cannabinoid-based interventions hold promise for preserving neural circuits and modulating cognitive function in PD; however, well-designed, mechanism-informed trials with standardized, domain-specific cognitive endpoints are essential before clinical recommendations can be made.”

https://pubmed.ncbi.nlm.nih.gov/41864320

“Endocannabinoid system participates in cognitive modulation in Parkinson’s disease.”

https://www.ibroneuroscience.org/article/S0306-4522(26)00197-1/abstract

Therapeutic relevance of an EU-GMP certified Cannabis sativa L. strain in a dual in vivo model of cognitive impairment and chronic neuropathic pain

Background: Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline and frequently co-occurs with chronic pain. Worldwide, over 55 million people are affected by AD, with nearly half experiencing persistent pain. Chronic pain has been linked to accelerated memory deterioration and an increased risk of dementia, but the interplay between these conditions remains poorly understood. Existing therapies for AD and chronic pain are limited in efficacy, highlighting the need for interventions targeting multiple pathological pathways. The endocannabinoid system, which is altered in both AD and chronic pain, represents a potential therapeutic target, though its role in AD patients with comorbid pain remains unexplored.

Methods: The study evaluated the effects of an EU-GMP certified Cannabis sativa L. strain (5 mg/kg, Cannabixir® Medium Flos) on neurobiological alterations in a rat model designed to explore mechanistic interactions between scopolamine-induced transient cognitive impairment and chronic neuropathic pain induced by unilateral sciatic nerve ligation. Treatment outcomes were assessed through nociceptive tests, clinical monitoring and tissue analyses to examine cognitive and pain-related effects.

Results: Cannabixir® Medium Flos induced robust, time-dependent analgesia in thermal nociceptive tests, with the combination of the Cannabis sativa L. strain, donepezil and tramadol producing significantly longer response latencies than tramadol alone. Mechanical sensitivity was minimally affected across treatments. Immunohistochemical analyses revealed that Cannabixir® Medium Flos, either alone or in combination with donepezil or tramadol, produced the most pronounced neuroprotective effects, reducing astrocytic (GFAP) and microglial (Iba1) activation, lowering Caspase-3 and IL-6 expression, and preserving both hippocampal neuronal integrity as well as peripheral nerve structure.

Conclusion: These findings indicate that Cannabixir® Medium Flos, particularly when combined with donepezil and tramadol, provides superior analgesic and neuroprotective effects compared to tramadol alone. Its multi-target action – alleviating thermal nociception, reducing neuroinflammation, limiting apoptosis and preserving neuronal and peripheral nerve integrity-supports its potential as an adjunct therapy in managing dementia with comorbid chronic neuropathic pain. Future studies should explore the molecular mechanisms underlying these effects and assess long-term safety and efficacy across diverse models of neurodegeneration and chronic pain.”

https://pubmed.ncbi.nlm.nih.gov/41800101

https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2026.1761426/full

Peripheral Cannabinoid Receptor Activation Attenuates Frostbite-Induced Chronic Pain via Modulation of TRP Channels, Neuroinflammation, and Autophagy

“Frostbite injury is a debilitating cold injury encountered in extreme high-altitude and subzero environments, frequently resulting in persistent chronic pain even after tissue healing. Using our previously validated frostbite-induced chronic pain model, we further investigated the contribution of neuroimmune, excitatory mechanisms and evaluated the therapeutic efficacy of peripheral cannabinoid receptor activation.

Frostbite produced significant mechanical allodynia, mechanical hyperalgesia, and cold hypersensitivity, along with increased spontaneous nocifensive behaviors.

Local peripheral administration of CB13, a peripherally acting CB1/CB2 receptor dual agonist, dose-dependently attenuated both mechanical and cold allodynia without impairing locomotor activity, indicating a lack of central nervous system side effects.

At the molecular level, frostbite induced marked peripheral and spinal sensitization, demonstrated by elevated expression of TRPV1, TRPA1, TRPV4, and TRPM8 channels, increased levels of pro-inflammatory cytokines, and enhanced c-Fos expression as an indicator of heightened neuronal activation in pain-relevant regions. These alterations were accompanied by pronounced microglial activation and upregulation of the NLRP3 inflammasome.

CB13 treatment significantly reversed these pathological changes and concurrently restored Beclin-1-associated autophagy signaling, suggesting engagement of both neuroimmune resolution and intracellular homeostasis pathways. Notably, frostbite injury was associated with marked oxidative and nitrosative stress in the sciatic nerve, as evidenced by reduced glutathione depletion and elevated lipid peroxidation and nitrite levels, which were significantly normalized by CB13 treatment.

Collectively, these findings demonstrate that peripheral cannabinoid receptor activation effectively inhibit frostbite induced chronic pain through modulation of nociceptive, neuroinflammatory, redox, and cellular stress pathways.

This work highlights peripherally selective cannabinoid receptor agonists as promising, safer therapeutic strategies for chronic pain associated with cold injuries.”

https://pubmed.ncbi.nlm.nih.gov/41802611

“This study demonstrates that peripheral cannabinoid receptor activation via CB13 effectively alleviates frostbite-induced chronic pain by targeting multiple pathological mechanisms, including nociceptor hyperexcitability, spinal neuronal activation, neuroinflammation, inflammasome signaling, oxidative stress, and impaired autophagy.”

https://www.sciencedirect.com/science/article/abs/pii/S0891584926001565?via%3Dihub

Cannabidiol and cannabigerol ameliorate steatotic liver disease via phosphocreatine buffering and lysosomal restoration

Background and purpose: Cannabidiol (CBD) and cannabigerol (CBG) are non-psychoactive phytocannabinoids with emerging therapeutic potential in metabolic dysfunction-associated steatotic liver disease (MASLD). However, the molecular mechanisms underlying their beneficial effects remain incompletely understood. In this study, we assessed the metabolomic and lipidomic impact of CBD and CBG in a mouse model of diet-induced obesity and MASLD.

Experimental approach: Male C57Bl/6 mice fed on a high-fat diet for 14 weeks were treated for 4 weeks with daily intraperitoneal CBD, CBG or vehicle. Assessments included body composition, indirect calorimetry, glucose tolerance, serum biochemistry and VLDL-triglyceride profiling. Hepatic mechanisms were examined by metabolomics, lipidomics, creatine kinase activity, cathepsin activity-based probes and gene/protein expression, with a choline-deficient diet cohort to test phospholipid-dependence of CBG.

Key results: CBD or CBG treatment improved glycaemic control, reduced hepatic triglycerides and normalised serum lipids, without affecting energy expenditure. Metabolomics revealed increased hepatic phosphocreatine and creatine with enhanced creatine kinase activity, indicating phosphocreatine-based energy buffering independent of fatty acid oxidation changes. Lipidomics showed reduced triglycerides and ceramides, with increased phospholipids and lysobisphosphatidic acids, correlating with restored hepatic cathepsin activity and improved lysosomal lipid degradation. CBG was ineffective in choline-deficient MASLD, indicating phospholipid pathway dependence.

Conclusions and implications: These findings identify a novel, endocannabinoid system-independent mechanism by which CBD and CBG enhance hepatic energy buffering and lysosomal function, contributing to improved liver lipid handling and supporting phytocannabinoids as promising MASLD therapeutics.”

https://pubmed.ncbi.nlm.nih.gov/41785476

Alcohol as a Novel Trigger for Cannabis Hyperemesis Syndrome

“Cannabis hyperemesis syndrome (CHS) is a paradoxical condition occurring in chronic cannabis users, characterized by cyclic nausea, vomiting, and abdominal pain. While the primary trigger is cannabis itself, other precipitants remain poorly defined.

We present the case of a 52-year-old male with recurrent CHS who experienced five distinct hyperemetic episodes, each occurring approximately one week after ingesting a single dose of alcohol. His most recent presentation was complicated by severe, life-threatening hyponatremia requiring intensive care unit management. Diagnostic workup confirmed CHS and excluded other pathologies.

The consistent temporal pattern observed across multiple episodes suggests that a single dose of alcohol may be a novel and specific trigger for CHS. This case highlights a previously underreported precipitant and underscores the syndrome’s potential for severe metabolic complications. Clinicians should consider inquiring about alcohol use in patients with recurrent CHS, as its identification could be pivotal for prevention strategies and patient counseling.”

https://pubmed.ncbi.nlm.nih.gov/41769444

“This case provides critical clinical insights by identifying a single dose of alcohol as a potential novel trigger for CHS, expanding the known spectrum of precipitants. It underscores the serious morbidity of CHS, which can progress to life-threatening complications like severe hyponatremia necessitating intensive care.”

https://www.cureus.com/articles/434462-alcohol-as-a-novel-trigger-for-cannabis-hyperemesis-syndrome#!

“Binge Alcohol Exposure Transiently Changes the Endocannabinoid System: A Potential Target to Prevent Alcohol-Induced Neurodegeneration.”

https://pmc.ncbi.nlm.nih.gov/articles/PMC5742761

Endocannabinoid Modulation in Headache: Mechanisms, Models, and Translational Therapies

“Headache disorders, including migraine, tension-type headache, trigeminal autonomic cephalalgias, post-traumatic headache and medication overuse headache, represent a major global health burden and remain difficult to treat despite therapeutic advances.

The endocannabinoid system (ECS) has emerged as a key regulator of neural, vascular, and immune processes central to headache pathophysiology.

Through coordinated actions of CB1 and CB2 receptors, the endogenous ligands anandamide (AEA) and 2-arachidonoylglycerol (2-AG), and their metabolic enzymes, the ECS modulates trigeminovascular activity, descending pain control, cortical excitability, and neuroimmune sensitization.

Preclinical studies demonstrate that ECS activation suppresses trigeminal firing, reduces calcitonin gene-related peptide (CGRP) release, attenuates neurogenic inflammation, stabilizes cortical susceptibility to spreading depression, and limits glial activation following traumatic brain injury. Conversely, ECS dysregulation contributes to central sensitization and impaired descending inhibition underlying medication overuse headache and other headache disorders.

Pharmacological strategies targeting endocannabinoid degradation, such as inhibition of FAAH, MAGL, and COX-2, enhance endogenous cannabinoid tone and consistently reduce headache-like behaviors across diverse models. Importantly, sex differences shape ECS function, with females exhibiting distinct hormonal regulation, receptor expression, and glial activation that influence responsiveness to ECS-targeted interventions.

Collectively, mechanistic and translational evidence highlights the ECS as a promising therapeutic target across primary and secondary headache disorders. Future clinical studies should incorporate sex-informed designs, integrate biomarkers of trigeminovascular and neuroimmune activity, and evaluate peripherally restricted ECS modulators and cannabinoid-based formulations as candidates for individualized headache therapy.”

https://pubmed.ncbi.nlm.nih.gov/41744774

  • “The endocannabinoid system (ECS) is a central regulator of neural, vascular, and immune mechanisms driving headache disorders.
  • ECS dysfunction contributes to central sensitization and reduced descending inhibition, particularly in chronic headaches.
  • Targeting endocannabinoid hydrolysis and oxygenation shows consistent preclinical efficacy and represents a promising therapeutic strategy.”

https://www.mdpi.com/2073-4409/15/4/331

The dual roles of natural cannabidiol in combating oxidative stress and inflammation: A potential intestinal guardian

“Cannabidiol (CBD), a non-psychoactive and non-addictive phytocannabinoid derived from Cannabis sativa L., has attracted increasing attention for its therapeutic potential in intestinal diseases.

Accumulating evidence indicates that CBD exerts prominent antioxidant and anti-inflammatory effects within the gastrointestinal tract. Oxidative stress and redox imbalance are key drivers of epithelial barrier dysfunction, chronic inflammation, and disease progression in disorders such as inflammatory bowel disease (IBD) and colorectal cancer (CRC).

This review focuses on the redox-related mechanisms underlying CBD’s intestinal protective actions, highlighting its ability to regulate reactive oxygen species (ROS) production, activate the Nrf2-Keap1 antioxidant pathway, and modulate redox-sensitive inflammatory signaling, including NF-κB and the NLRP3 inflammasome.

In parallel, CBD engages the endocannabinoid system (ECS) and related receptors to preserve epithelial barrier integrity, regulate gut microbiota composition, and modulate intestinal oxidative stress and inflammation. We further discuss emerging evidence linking CBD’s regulation in the gut to systemic effects along the gut-organ axis, including the gut-brain and gut-liver axes.

Overall, this review synthesizes current evidence on how CBD integrates redox modulation, inflammation control, and intestinal barrier protection, providing a mechanistic framework for its potential application in intestinal disease and health.”

https://pubmed.ncbi.nlm.nih.gov/41713221

“CBD, as a non-psychoactive phyto-CB, has demonstrated substantial therapeutic potential for gastrointestinal health. By modulating the ECS, CBD enhances intestinal barrier integrity, regulates GM composition, and mitigates oxidative stress and inflammation. These effects contribute to its promising role in treating oxidative stress-related gastrointestinal conditions and maintaining intestinal homeostasis.”

https://www.sciencedirect.com/science/article/pii/S2213231726000492?via%3Dihub

Altered endocannabinoid system gene expression in inflammatory bowel disease mucosa: New perspectives in inflammatory bowel disease management

Background: Inflammatory bowel disease (IBD) is a broad classification including various chronic inflammatory gastrointestinal conditions that comprises two main disorders: Crohn’s disease (CD) and ulcerative colitis (UC). The key components of the endocannabinoid system (ECS) are highly expressed within the gastrointestinal tract, playing a crucial role in maintaining homeostasis and providing protection against intestinal inflammation.

Aim: To investigate possible impairment of the genes belonging to ECS by analyzing their expression levels in IBD patients and controls.

Methods: The paired biopsies of endoscopically inflamed (IM) and noninflamed (NIM) colonic mucosa from 30 IBD-diagnosed patients (17 UC and 13 CD), and the colonic mucosa from 17 non-IBD controls, were collected and analyzed. The messenger RNA expression level of cannabinoid receptor (CNR) 1, CNR 2, diacylglycerol lipase alpha, diacylglycerol lipase beta, fatty acid amide hydrolase (FAAH), G protein-coupled receptor (GPR) 18, GPR55, monoglyceride lipase, peroxisome proliferator-activated receptor gamma (PPARG), and transient receptor potential cation channel, subfamily V, member 1 (TRPV1) was determined by quantitative polymerase chain reaction.

Results: Six out of the 10 investigated genes were found to be dysregulated in at least one comparison. Specifically, in IBD patients, FAAH, PPARG, and TRPV1 were significantly downregulated in IM compared to NIM (FAAH, P = 0.012; PPARG, P = 0.001; TRPV1, P = 0.032) and in IM compared to controls (FAAH, P < 0.001; PPARG, P < 0.001; TRPV1, P = 0.002). An opposite trend was reported for CNR2 and GPR55, which showed an upregulation in IM compared to NIM (CNR2, P = 0.005; GPR55, P = 0.001).

Conclusion: We found a significant impairment of the ECS in IBD patients. Further analyses on larger cohorts are needed for a better understanding of the potential of cannabinoids in managing IBD.”

https://pubmed.ncbi.nlm.nih.gov/41700170

“The role of ECS in gastrointestinal physiology and the exact involvement of this system in IBD are still under investigation. Given this, our preliminary findings of the impairment of analyzed ECS genes in the IBD mucosa may serve as a basis for more in-depth research in larger cohorts to better understand the potential of cannabinoids in the management of IBD. After the introduction of artificial intelligence in the multi-omics drug delivery pipeline, future therapeutic targets should emerge, allowing for an even more personalized approach to IBD patients.”

https://www.wjgnet.com/1948-5190/full/v18/i2/113576.htm?appgw_azwaf_jsc=pjmb6U0PmJ8Jhw6KK0wkG7dIIANmqb_h-_TRqMyZe5S0n2nN12xjj6IEXzXltFiMGkrPy5gdVTqeL9FpqEwxg2IRdQtlxGphrdrCTC-8UB5iTS-53eOUekwL8V6ddoD3rUPUEsVlA14gjfLy8jmezIuYPV2vjfZ-Qoy-hEGym4pY7k9iS4yH7a1n8E6oEldBMV5stbazp3UctrqNhXMRb1bGo8NvE8b14zuvRdlvOI8MhNFNMTV-JysZCgnImMJg1XC1kSYNzlziNr4LuxGaowrDxyFS9KaRq_rQ_cNEf6ip8MXlhXSmgIWPhdPyy1s0xQclW9zOboCaV9pRBR83KQ

Activation of Cannabinoid Receptor 1 Enhances Wound Healing by Promoting the Proliferative Phase

“The mechanisms underlying wound healing mediated by cannabinoid receptor 1 (CB1)-known for its neuromodulatory functions-remain incompletely understood. Therefore, we investigated the impact of activating CB1 using specific agonists, both in vitro and in vivo, with a focus on wound healing.

In the in vitro study, fibroblasts were isolated and cultured from the dermis of human skin and treated with a CB1 agonist, 2-arachidonyl glyceryl ether (2-AGE). In the in vivo study, a mouse acute wound model was created using a skin biopsy punch and treated with the CB1 agonist arachidonoyl 2′-chloroethylamide (ACEA).

The in vitro study revealed that 2-AGE increased cell proliferation and differentiation, upregulated the expression of alpha-smooth muscle actin (α-SMA), N-cadherin, and vimentin, and enhanced cell migration as well as the synthesis of type I and III collagen and fibronectin in normal human dermal fibroblasts. The CB1 antagonist AM251 abolished 2-AGE-induced expression of α-SMA, type I collagen, and fibronectin. In vivo, ACEA treatment accelerated wound closure, increased expression of α-SMA, type I collagen, and fibronectin, and ultimately increased epidermal and dermal thickness.

Overall, these findings suggest that the activation of CB1 promotes wound healing and provides evidence for the therapeutic potential of CB1 agonists in wound treatment.”

https://pubmed.ncbi.nlm.nih.gov/41683598

“Recent research has highlighted the role of the endocannabinoid system (ECS) in skin physiology and repair.”

“Clinical evidence indicates that the topical application of Cannabis-Based Medicines (TCBMs) facilitates tissue repair and promotes complete wound closure in previously refractory wounds.”

“In conclusion, our findings support the hypothesis that CB1 receptor activation facilitates wound healing through both cellular and molecular mechanisms.”

“Thus, these findings strongly support the therapeutic potential of targeting specific agonists as a viable strategy to accelerate the proliferative or contractile phases and thereby enhance the rate of wound healing.”

https://www.mdpi.com/1422-0067/27/3/1171


Role of Endocannabinoid System Perturbation in Organophosphate-Mediated Metabolic Impairment and Neuroinflammation

“Organophosphates have been used for decades as pesticides, insecticides and herbicides, both in agricultural and industrial settings. However, their toxic effects on multiple body systems limit their safety. The clinical presentation of organophosphate toxicity varies depending on the route and duration of exposure. Although most research is focused on their cholinergic toxicity, emerging evidence points to their crucial contribution to metabolic dysfunction, including Type 2 diabetes and neuroinflammation.

Beyond acetylcholinesterase inhibition, recent research highlights the potential role of organophosphates in disrupting endocannabinoid signalling, particularly by affecting endogenous ligands that modulate G protein-coupled receptors. This dysregulation may contribute to organophosphate-induced metabolic disturbances and inflammation.

This review aims to explore how chronic subtoxic exposure to organophosphates contributes to metabolic syndrome and neuroinflammation through disruption of insulin and endocannabinoid signalling. It highlights the role of the endocannabinoid system in mediating these effects and evaluates its potential as a therapeutic target in organophosphate-induced toxicity.”

https://pubmed.ncbi.nlm.nih.gov/41668464

Plain language summary

“Organophosphates (OPs), commonly used as pesticides, have been shown to adversely affect both metabolism and brain health by disrupting the endocannabinoid system (ECS), a critical regulatory network involved in inflammation, energy balance, and neural function. Chronic, low‐dose exposure to OPs can alter ECS enzymes and signalling pathways, contributing to insulin resistance, obesity and neuroinflammation. These metabolic disturbances may play a key role in the development of neurodegenerative outcomes associated with OP toxicity. This review aims to examine the interplay between OPs exposure and ECS disruption, emphasizing the ECS role in pathogenesis and its potential as a therapeutic target.”

https://onlinelibrary.wiley.com/doi/10.1111/bcpt.70198