Category Archives: Endocannabinoid System

Cannabidiol prevents cognitive and social deficits in a male rat model of Alzheimer’s disease through CB1 activation and inflammation modulation

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“Cognitive decline is a hallmark of Alzheimer’s disease (AD). Cannabidiol (CBD), a non-intoxicating phytocannabinoid with immunomodulatory properties, shows promise in alleviating AD symptoms.

This study examined the effects of chronic CBD treatment in a male rat model of sporadic AD induced by intracerebroventricular streptozotocin (ICV-STZ) and explored its impact on neuroinflammatory genes and cannabinoid signaling.

STZ rats showed impaired performance in object location and recognition tasks, along with reduced social behavior. STZ exposure also affected AD-related hippocampal markers, leading to increased levels of amyloid β-protein (Aβ) and tau phosphorylation (p-Tau) and elevated mRNA levels of triggering receptor expressed on myeloid cells 2 (TREM2) and apolipoprotein E4 (APOEε4). Additionally, STZ increased hippocampal neuroinflammatory markers, including mRNA levels of Tumor Necrosis Factor α (TNF-α), nuclear factor kappa B subunit 1 (NF-κB1), and interleukin (IL)-1β. It also altered cannabinoid receptor expression, with cannabinoid receptor 1 (cnr1) and 2 (cnr2) genes upregulated in the dentate gyrus (DG), whereas in the CA1, cnr2 was upregulated and cnr1 downregulated.

Chronic CBD treatment restored the STZ-induced behavioral deficits, reduced neuroinflammatory marker expression, and mitigated AD-associated changes. Importantly, the CB1 receptor antagonist AM251, but not CB2 antagonist AM630, blocked the beneficial effects of CBD on performance in object location and social tasks in STZ-treated rats, highlighting CB1 receptor activation as a key mechanism.

These findings suggest that CBD holds promise as a therapeutic agent for inflammation-induced AD, with the potential to ameliorate cognitive deficits and prevent disease onset through mechanisms involving CB1 receptor activation and modulation of neuroinflammation.”

https://pubmed.ncbi.nlm.nih.gov/40859005/

“Our findings suggest that CBD protects against STZ-induced cognitive and social deficits, hippocampal neuroinflammation, and AD-related pathology, with CB1r playing a key role in its therapeutic effects. As current AD treatments are limited, our study highlights CBD as a promising candidate, demonstrating for the first time that a low dose can prevent behavioral and molecular deficits in a rodent model of sporadic AD. By targeting neuroinflammation and endocannabinoid pathways, CBD may help prevent cognitive decline and neuropathological changes in AD.”

https://www.nature.com/articles/s41386-025-02213-0

Cannabinoid Receptors CB1 and CB2 Activation Restores Hippocampal Lipid Profiles and Alleviates Autism-Like Behaviors in Valproic Acid-Induced ASD Rats

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“Objective: Emerging evidence suggests lipid metabolism dysregulation contributes to autism spectrum disorders (ASD), with the endocannabinoid system (cannabinoid receptors CB1R/CB2R) implicated in lipid homeostasis. This study investigated whether CB1R/CB2R activation improves hippocampal lipid metabolism and ASD-like behaviors in a valproic acid (VPA)-induced ASD rat model.

Methods: Male offspring from dams exposed to VPA (600 mg/kg, i.p.) received the CB1R agonist ACPA (0.1 mg/kg) or the CB2R agonist AM1241 (3 mg/kg) from postnatal days 21-27. ASD-like behaviors (marble burying, self-grooming, social interaction, open-field tests) and hippocampal lipid profiles (UPLC-MS/MS) were analyzed.

Results: VPA-exposed rats displayed heightened repetitive behaviors, social deficits, and hyperactivity, all significantly alleviated by ACPA and AM1241. Lipidomics revealed marked reductions in hippocampal phosphatidylcholines, lysophosphatidylcholines, fatty acids, sphingomyelins, ceramides, and phosphatidylethanolamines in VPA rats. Both agonists restored lipid levels to near normal, comparable to controls.

Conclusions: CB1R/CB2R activation ameliorates behavioral abnormalities and rectifies hippocampal lipid dysregulation in VPA-induced ASD models, highlighting cannabinoid receptors as potential therapeutic targets for ASD-associated metabolic disturbances.”

https://pubmed.ncbi.nlm.nih.gov/40852923/

“This study provides new evidence linking ASD-like behaviors, lipid metabolism abnormalities, and endocannabinoid system regulation. Our results demonstrated that CB1R and CB2R activation alleviated VPA-induced ASD-like behaviors and restored disrupted lipid profiles in the hippocampus, suggesting a potential therapeutic approach for ASD. Further research should explore the molecular mechanisms underlying CB1R- and CB2R-mediated lipid regulation and their implications for ASD treatment strategies.”

https://onlinelibrary.wiley.com/doi/10.1111/cns.70591

The Endocannabinoid System: Role in Ocular Physiology and Therapeutic Potential in Eye Diseases: A Narrative Review

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“The endocannabinoid system (ECS) is a multicomponent signaling network that controls several physiological processes, including neurological, immune, cardiovascular, digestive, and ocular functions. The components of ECS (i.e., receptors, ligands, metabolizing enzymes, and carriers) are expressed in eye structures and neurological areas involved in the visual process. Experimental evidence supports ECS involvement in ocular pathophysiology.

Preclinical and clinical studies indicate that cannabinoids (CBs) lower intraocular pressure and exert vasoactive, anti-inflammatory, and protective effects in the retina and ocular surface. However, CBs elicit modest and transient effects while inducing tolerance, dependence, and adverse effects, which prevent their use in ophthalmic clinics.

This review summarizes experimental and clinical data on the role of ECS in ocular pathophysiology. It also reports research on the therapeutic potential of CBs in common eye disorders. Lastly, it highlights promising alternative strategies for modulating ECS and improving ocular drug delivery to improve therapeutic efficiency in ophthalmic clinics.”

https://pubmed.ncbi.nlm.nih.gov/40838892/

The Role of the Endocannabinoid System in Oncology and the Potential Use of Cannabis Derivatives for Cancer Management in Companion Animals

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“The last decades of research have shown that the endocannabinoid system may be a promising therapeutic target for the pharmacological treatment of cancer in human medicine and possibly in veterinary medicine as well.

Compared with the original cells, the expression of gene encoding for receptors and enzymes belonging to the endocannabinoid system has been found to be altered in several tumor types; it has been hypothesized that this aberrant expression may be related to the course of the neoplasm as well as to the patient’s prognosis.

Several studies, conducted both in vitro and in vivo, suggest that both endo- and phytocannabinoids can modulate signaling pathways, controlling cell proliferation and survival. In the complex process of carcinogenesis, cannabinoids seem to intervene at different levels by stimulating cell death, inhibiting the processes of angiogenesis and metastasis, and regulating antitumor immunity.

Although the molecular mechanisms by which cannabinoids act are not always clear and defined, their synergistic activity with the most used antineoplastic drugs in clinical oncology is showing promising results, thus providing veterinary medicine with alternative therapeutic targets in disease control.

This review aims to summarize current knowledge on the potential role of the endocannabinoid system and exogenous cannabinoids in oncology, with specific reference to the molecular mechanisms by which cannabinoids may exert antitumor activity. Additionally, it explores the potential synergy between cannabinoids and conventional anticancer drugs and considers their application in veterinary oncology.”

https://pubmed.ncbi.nlm.nih.gov/40804975/

“Companion animals are more and more becoming considered family members, and their owners wish to offer them the same level of cure and care expected for a human being. The long life expectancy of dogs and cats is associated with new challenges: veterinary medicine must be prepared to diagnose and treat neoplastic pathology with the same high-standard procedures that are currently used in human medicine.

Chemotherapies aim to prolong as long as possible the life of companion animals affected by cancer, but several side effects can be experienced. Thus, an increasing interest in alternative and complementary treatments has arisen in the last years. Among a wide array, cannabinoids seem to be a promising tool to be included in therapeutic protocols since their administration could assist traditional chemotherapeutic agents, promoting a more successful antineoplastic effect, prolonging the prognosis, and contributing to patient well-being thanks to pain relief.

According to all the aforementioned factors, the present review aims to summarize how the endocannabinoid system and phytocannabinoids interact in the complex process of carcinogenesis, exploring current therapeutical applications and future perspectives in veterinary oncology.”

“From the above paragraphs, it can be concluded that cannabinoids show antitumor activity (decrease in tumor growth and invasiveness) in numerous cell lines and in various animal models of cancer, and that, although clinical studies conducted in human and animal patients are limited, the results obtained so far have demonstrated that cannabinoids appear to be safe and effective antineoplastic agents.

Moreover, most of the preclinical evidence currently available demonstrates that the greatest therapeutic potential of cannabinoids lies in their combination with existing chemotherapeutic drugs.

Interestingly, compared to conventional antineoplastic drugs, which have a plethora of side effects, cannabinoids (especially the non-psychoactive ones, such as CBD) have a broad safety margin. “

https://www.mdpi.com/2076-2615/15/15/2185

The Endocannabinoid System in PTSD: Molecular Targets for Modulating Fear and Anxiety

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“Fear and anxiety perform essential protective roles, yet when they become dysregulated, they can trap trauma survivors in persistent hypervigilance and distress. Post-traumatic stress disorder (PTSD) manifests as intrusive memories, avoidance, and heightened arousal long after the precipitating event. Although current pharmacotherapies – including selective serotonin reuptake inhibitors, adrenergic blockers, benzodiazepines, and atypical antipsychotics – provide relief for some, many patients contend with residual symptoms or intolerable adverse effects.

Recent discoveries position the endocannabinoid system as a pivotal regulator of fear acquisition, consolidation, and extinction. Clinical observations of altered anandamide levels and cannabinoid receptor CB₁ upregulation in individuals with severe PTSD underscore the therapeutic potential of restoring endocannabinoid tone.

Preclinical studies demonstrate that direct CB₁ agonists, fatty acid amide hydrolase (FAAH) inhibitors, and phytocannabinoids such as tetrahydrocannabinol (THC) and cannabidiol (CBD) can facilitate extinction learning and attenuate anxiety-like behaviours.

Preliminary human trials report that nabilone alleviates trauma-related nightmares and that acute cannabinoid administration modulates amygdala reactivity to a threat. Yet optimal dosing strategies, sex-specific responses, and ideal THC:CBD ratios remain to be defined. Self-medication with cannabis can offer transient relief but carries a risk of cannabis use disorder and potential worsening of PTSD symptoms. By elucidating molecular targets – including CB₁, CB₂, FAAH, and monoacylglycerol lipase – this review outlines a strategic framework for next-generation cannabinoid-based interventions.

Harnessing the endocannabinoid system promises to expand the therapeutic arsenal for PTSD, offering hope for more effective and better-tolerated treatments.”

https://pubmed.ncbi.nlm.nih.gov/40789309/

https://www.thieme-connect.de/products/ejournals/abstract/10.1055/a-2647-8030

Local release of fibroblast growth factor 21 and cannabidiol promoting spinal cord nerve injury repair through activation of cannabinoid receptor 2

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“Spinal cord injury (SCI) is a debilitating condition that leads to severe motor and sensory dysfunction, largely due to inflammation, neuronal damage, and disrupted neural circuits.

In this study, we developed an injectable hydrogel (C/F/Gel) co-loaded with fibroblast growth factor 21 (FGF21) and cannabidiol micelles (CBDm) to enhance SCI repair. The hydrogel, composed of PF127 and α-cyclodextrin (α-CD), provides sustained drug release and improves drug stability at the injury site.

Our findings demonstrate that C/F/Gel effectively modulates the inflammatory microenvironment by promoting microglial polarization toward the anti-inflammatory M2 phenotype via cannabinoid receptor 2 (CB2R) activation.

Additionally, it regulates the balance between excitatory and inhibitory neurons, and significantly improves motor function in SCI mice. Behavioral assessments, histological analysis, and molecular studies confirmed the superior therapeutic efficacy of C/F/Gel compared to single-agent treatments.

These results highlight C/F/Gel as a promising biomaterial-based strategy for SCI repair, offering a synergistic approach that integrates inflammation modulation, neuroprotection, and functional recovery.”

https://pubmed.ncbi.nlm.nih.gov/40782447/

“Our study shows that the developed C/F/Gel is a promising therapeutic strategy for SCI repair, offering a multi-faceted approach through controlled drug release, inflammation modulation, neural regeneration, and motor function recovery. The synergy between FGF21 and CBDm, particularly via CB2R activation, highlights a novel mechanistic pathway for SCI treatment.”

https://www.sciencedirect.com/science/article/abs/pii/S0142961225005289?via%3Dihub

Exploring the impact of chronic intermittent EU-GMP certified Cannabis sativa L. therapy and its relevance in a rat model of aging

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“Background: Aging is a multifaceted process marked by the progressive accumulation of cellular damage in various tissues, resulting in a decline in physiological functions. The primary aim of aging research is to identify compounds that can delay or mitigate these detrimental changes. As cannabis legalization becomes more widespread and with limited empirical studies on its effects in the aging human population, there is a pressing need for research into the impact of Cannabis and cannabinoids on healthy aging and age-related diseases.

Methods: Our study aims to evaluate the effects of chronic, intermittent exposure, defined as 6 weeks of use of EU-GMP certified Cannabis sativa L. (Cannabixir® Medium Flos) administration, dosed at 6.25 and 25 mg/kg on neurobiological changes in naturally aged rats and its potential efficacy in mitigating age-related alterations. The impact of the Cannabixir® Medium Flos was assessed through clinical, histopathological, immunohistochemical, and behavioral evaluations.

Results: Cannabixir® Medium Flos was found to be generally safe, with no significant effects on motor performance and a neutral effect on anxiety-like behavior. Histological analysis revealed that the hippocampus of aged rats treated with this compound-an area known for its abundance of endocannabinoids and cannabinoid receptor type 1-exhibited characteristics similar to those observed in young adult rats. Additionally, the study suggests that chronic, intermittent treatment with Cannabixir® Medium Flos may modulate astrocyte function, reduce neuroinflammation, and potentially influence cell proliferation and neuronal apoptosis in a dose-dependent manner. However, these preliminary findings should be interpreted with caution, as the study’s exploratory nature.

Conclusions: These preliminary findings suggest that cannabinoid therapy targeting the endocannabinoid system may offer potential neuroprotective benefits in aging.

While the study offers valuable preclinical insights into the effects of an EU-GMP-certified cannabinoid receptor ligand in reducing age-related cognitive decline, these effects are likely mediated by a combination of mechanisms. Given the complex phytochemical composition, the observed outcomes cannot be attributed exclusively to cannabinoid receptor activation. Accordingly, these findings should be interpreted with caution, and further studies employing more targeted methodologies are needed to elucidate the underlying mechanisms.”

https://pubmed.ncbi.nlm.nih.gov/40770774/

“Targeting the ECS could be a promising strategy for developing therapies aimed at promoting healthy aging and longevity.”

https://jcannabisresearch.biomedcentral.com/articles/10.1186/s42238-025-00313-8

Transient CB2 receptor activation triggers irreversible luminal differentiation via chromatin remodeling in breast cancer

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“Cellular plasticity enables cancer cells to escape therapy by adopting stem-like or alternate lineage states. Here, we identify a mechanism by which cannabinoid receptor 2 (CB2R) activation promotes irreversible lineage commitment in breast cancer. Using patient-derived and murine organoids, we show that brief, low-dose exposure to CB2R agonists—either phytogenic or synthetic—induces a basal-to-luminal transition, accompanied by reduced self-renewal, invasiveness, and tumor-initiating potential. These changes are retained under conditions that normally promote dedifferentiation, including fibroblast co-culture, immune pressure, and mechanical shear stress.

Mechanistically, CB2R engagement initiates a transient chromatin remodeling program, marked by early expression of pluripotency-associated genes followed by silencing and differentiation commitment. This epigenetically stabilized state renders tumor cells more responsive to tamoxifen and limits the emergence of resistant clones.

Our findings uncover a previously unrecognized role for CB2R in modulating cancer cell identity and suggest new opportunities to constrain tumor plasticity by directing differentiation through a drug-responsive pathway.”

https://www.biorxiv.org/content/10.1101/2025.07.29.667375v2

CB2R-induced differentiation epigenetically restrains cancer plasticity enabling adaptive therapy

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“Tumor adaptability relies on the ability of cancer cells to dedifferentiate and acquire stem-like features, fueling therapeutic resistance and metastasis. Differentiation therapy aims to reprogram tumor cells into more mature, less aggressive states to counteract this plasticity.

Here, we identify cannabinoid receptor 2 (CB2R) as a novel therapeutic target that promotes sustained differentiation in breast cancer. Using tumor-derived organoids from both mouse models and patient biopsies, we show that brief, low-dose exposure to phytogenic or synthetic CB2R ligands induces a basal-to-luminal switch, suppresses stemness, and reduces invasiveness and self-renewal. These phenotypic changes are associated with decreased tumor initiation and aggressiveness in vivo .

Transcriptomic profiling reveals that CB2R activation initiates transient chromatin remodeling and epigenetic reprogramming, resulting in a stably differentiated state. Importantly, CB2R-driven differentiation sensitizes tumor cells to tamoxifen, enabling lower therapeutic doses with improved efficacy-supporting the principles of adaptive therapy aimed at long-term disease control.

Our findings position CB2R modulation as a promising non-cytotoxic strategy to restrict cancer plasticity and enhance the effectiveness of existing breast cancer treatments.”

https://pubmed.ncbi.nlm.nih.gov/40766353/

Anti-Inflammatory Effects of Cannabinoids in Therapy of Neurodegenerative Disorders and Inflammatory Diseases of the CNS

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“Many neurodegenerative diseases are associated with immune system disorders, while neurodegenerative processes often occur in inflammatory conditions of the Central Nervous System (CNS).

Cannabinoids exhibit significant therapeutic potential due to their dual ability to modulate both neural and immune functions. These compounds have a broad spectrum of action, allowing them to target multiple pathological mechanisms underlying neurodegenerative and inflammatory CNS diseases.

The present review outlines the therapeutic potential of cannabinoids, with a focus on their anti-inflammatory properties, in the treatment of neurodegenerative conditions, including Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, and Huntington’s disease, as well as inflammatory CNS disorders like multiple sclerosis and HIV-associated dementia.”

https://pubmed.ncbi.nlm.nih.gov/40724820/

“Cannabinoids, the active compounds derived from Cannabis sativa, are attracting increasing interest for their therapeutic potential in neurodegenerative disorders (Parkinson’s disease, Alzheimer’s disease, and Huntington’s disease) and inflammatory CNS conditions (multiple sclerosis and HIV-associated dementia).

Their multimodal mechanisms of action include the following: (1) modulating pathological protein aggregation and mitochondrial dysfunction, and (2) exerting neuroprotective and anti-inflammatory effects which are mediated through microglial regulation.

The neurodegenerative diseases and inflammatory CNS disorders discussed in this work represent a serious challenge for healthcare systems due to their complex etiology or pathophysiology, severe symptoms, and the limited effectiveness of existing treatments. Consequently, improving therapeutic strategies for these disorders remains a priority.

Many studies suggest that pharmacological modulation of the endocannabinoid system could influence neurodegenerative processes, providing a basis for further research into cannabinoid-based therapies. In particular, the inhibition of FAAH in the endocannabinoid system has emerged as a potential therapeutic approach to control neuroinflammatory processes.”

https://www.mdpi.com/1422-0067/26/14/6570