Cannabidiol and other cannabinoids reduce microglial activation in vitro and in vivo: relevance to Alzheimer's disease

Exploring the diversity of cannabis cannabinoid and non-cannabinoid compounds and their roles in Alzheimer's disease: A review

Cannabis sativa is recognized for its chemical diversity and therapeutic potential, particularly in addressing neurodegenerative diseases such as Alzheimer's disease (AD). Given the complexity of AD, where single-target therapies often prove inadequate, a multi-target approach utilizing cannabis-derived compounds may offer promising alternatives. This review first highlights the chemical diversity of cannabis by categorizing its compounds into cannabinoids and non-cannabinoids. It then examines studies investigating the effects of these compounds on AD-related pathological features. By synthesizing existing knowledge, identifying research gaps, and facilitating comparative analysis, this review aims to advance future research and understanding. It underscores cannabis's potential as a multi-target therapeutic strategy for AD, contributing valuable insights to ongoing scientific discussions.

Cannabidiol as a multifaceted therapeutic agent: mitigating Alzheimer's disease pathology and enhancing cognitive function

BACKGROUND

Cannabidiol (CBD), the second most abundant phytocannabinoid in Cannabis sativa, has garnered significant interest due to its non-psychoactive nature and diverse receptor interactions.

METHODS

This study employs in vitro and in vivo methodologies to validate CBD's potential as a treatment for Alzheimer's disease (AD) by addressing key hallmarks of the condition and promoting neuroprotective effects on spatial memory.

RESULTS

Our findings demonstrate CBD's ability to decrease pTau and Aβ aggregation and to mitigate their axonal transport between cortical and hippocampal neurons. Moreover, CBD treatment was shown to reduce neuroinflammation, as CBD was able to skew microglia towards a neuroprotective M2 phenotype while attenuating proinflammatory cytokine release in the 5xFAD AD mouse model. Notably, daily CBD injections (10 mg/Kg) for 28 days in 5xFAD mice resulted in significant improvements in both short- and long-term spatial memory. The study also reveals CBD's capacity to partially revert neurite formation loss induced by Aβ, Tau, and pTau proteins, suggesting a potential role in promoting neuronal plasticity. Additionally, CBD treatment led to a reduction in reactive oxygen species (ROS) formation and increased neuronal viability in the presence of AD-associated protein aggregates.

CONCLUSIONS

These multifaceted effects of CBD, ranging from molecular-level modulation to behavioral improvements, underscore its potential as a comprehensive therapeutic approach for AD. The findings not only support CBD's neuroprotective properties but also highlight its ability to target multiple pathological processes simultaneously, offering a promising avenue for future AD treatment strategies.

Engineered PLGA Nanoparticles for Brain-Targeted Codelivery of Cannabidiol and pApoE2 through the Intranasal Route for the Treatment of Alzheimer's Disease

Neuroinflammation induced by the accumulation of amyloid beta plaques expedites the progression of Alzheimer's disease (AD). Reducing Aβ plaques and associated neuroinflammation could potentially help to delay the progression of AD. Cannabidiol (CBD) is well-known for its antioxidant, anti-inflammatory, and neuroprotective nature, and the ApoE2 is effective in binding and clearing Aβ plaques in the brain. Therefore, codelivery of CBD and pApoE2 to the brain would be a promising therapeutic approach in developing effective therapeutics against AD. This research aims to design a nonviral delivery agent that delivers both drugs and genes to the brain through a noninvasive intranasal route. We have developed mPEG-PLGA nanoparticles coated with mannose, a brain-targeting ligand, to deliver CBD and pApoE2. The designed CBD-loaded coated nanoparticles showed an average diameter of 179.3 ± 4.57 nm and a zeta potential of 30.3 ± 6.45 mV. The coated nanoparticles prolonged the CBD release and showed a 93% release of its payload in 30 days. CBD-loaded nanoparticles, as compared to the free CBD, significantly reduced lipopolysaccharide and amyloid beta-induced inflammation in immortalized microglia cells. Cytotoxicity of the designed nanoparticles was assessed against brain endothelial cells (bEND.3) and found to be nontoxic in nature. The mannose-conjugated chitosan-coated nanoparticles were cationic and able to bind with the pApoE2, protecting the encapsulated pApoE2 from enzymatic degradation. Quantitative in vitro transfection efficiency study in primary astrocytes and primary neurons revealed that the ApoE2 expression level is significantly (P < 0.0001) higher for mPLGA-CBD-MC/pApoE2 than the control. The ApoE2 expression level in the brain of C57BL6/J mice was significantly (P < 0.0001) increased after intranasal administration of mPLGA-CBD-MC/pApoE2. Henceforth, the mannose-conjugated chitosan-coated mPLGA nanoparticles could serve as a nonviral delivery system to deliver both drugs and genes to the brain through the intranasal route for the management of AD.

Effects of cannabidiol (CBD) treatment on age-related cognitive decline in C57 mice

Aging is associated with cognitive decline, and currently, there are no approved medications that can prevent these impairments. Recently, cannabinoids derived from Cannabis sativa have emerged as promising therapeutic compounds with neuroprotective, anti-inflammatory, and cognitive-enhancing properties. Despite their benefits, further research is needed to fully understand their efficacy across various conditions. This study investigates the effects of cannabidiol (CBD) on memory impairment and brain inflammation in aging mice. Fourteen-month-old C57 mice were administered CBD orally for 7 months and subsequently evaluated between 19 and 21 months of age using behavioral tasks that are sensitive to dysfunction of the perirhinal cortex, hippocampus, amygdala, and various brain regions that are crucial for motor control and coordination. The findings of this study indicate that CBD reduces inflammatory response in the brain and improves cognitive decline associated with aging.

Cannabidiol ameliorates cognitive decline in 5×FAD mouse model of Alzheimer's disease through potentiating the function of extrasynaptic glycine receptors

Emerging evidence supports the therapeutic potential of cannabinoids in Alzheimer's disease (AD), but the underlying mechanism upon how cannabinoids impact brain cognition and AD pathology remains unclear. Here we show that chronic cannabidiol (CBD) administration significantly mitigates cognitive deficiency and hippocampal β-amyloid (Aβ) pathology in 5×FAD mouse model of AD. CBD achieves its curative effect mainly through potentiating the function of inhibitory extrasynaptic glycine receptor (GlyR) in hippocampal dentate gyrus (DG). Based on the in vitro and in vivo electrophysiological recording and calcium imaging, CBD mediated anti-AD effects via GlyR are mainly accomplished by decreasing neuronal hyperactivity of granule cells in the DG of AD mice. Furthermore, the AAV-mediated ablation of DG GlyRα1, or the GlyRα1S296A mutation that exclusively disrupts CBD binding, significantly intercepts the anti-AD effect of CBD. These findings suggest a GlyR dependent mechanism underlying the therapeutic potential of CBD in the treatment of AD.

Emerging nano-derived therapy for the treatment of dementia: a comprehensive review

Dementia includes a variety of neurodegenerative diseases that affect and target the brain's fundamental cognitive functions. It is undoubtedly one of the diseases that affects people globally. The ameliorating the disease is still not known; the symptoms, however, can be prevented to an extent. Dementia encompasses Alzheimer's disease, Parkinson's disease, Huntington's disease, Lewy body dementia, mixed dementia, and various other diseases. The aggregation of β-amyloid protein plaques and the formation of neurofibrillary tangles have been concluded as the foremost cause for the onset of the disease. As the cases climb, new neuroprotective methods are being developed in the form of new drug delivery systems that provide targeted delivery. Herbal drugs like Ashwagandha, Brahmi, and Cannabis have shown satisfactory results by not only treating the symptoms but have also been shown to reduce and ameliorate the formation of amyloid plaque formation. This article explores the intricate possibilities of drug delivery and the absolute use of herbal drugs to target neurodegenerative diseases. The various possibilities of nanotechnology currently available with new emerging techniques are also discussed.

Cannabidiol reverses myeloperoxidase hyperactivity in the prefrontal cortex and striatum, and reduces protein carbonyls in the hippocampus in a ketamine-induced schizophrenia rat model

BACKGROUND

Schizophrenia (SCZ) has limited treatment options, often with significant side effects. Cannabidiol (CBD), a non-euphoric phytocannabinoid, has shown potential as a novel therapeutic option in SCZ due to antipsychotic-like, anti-inflammatory, and antioxidant properties. We compared the therapeutic effects of CBD and risperidone (RISP) in a rat model of SCZ induced by sub-chronic ketamine (KET), focusing on inflammatory and oxidative stress, and behavioral phenotypes.

METHODS

Rats were pre-treated with KET or saline (SAL) for 10 days followed by CBD or RISP for 8 days. Locomotion, anxiety- and anhedonia-like behavior, and recognition memory were assessed. Oxidative damage as measured by protein carbonyls, thiobarbituric acid reactive substances, and catalase activity, and the inflammation markers myeloperoxidase (MPO) activity and nitrite/nitrate (N/N) concentration ratio were assessed in the prefrontal cortex (PFC), hypothalamus (HYP), hippocampus (HPC), and striatum, brain areas relevant to SCZ.

RESULTS

CBD restored the KET-induced decreased rearing behavior in the OFT, while RISP further decreased rearing. RISP treatment in control rats decreased rearing and elicited an anhedonic-like phenotype, while CBD did not. CBD, but not RISP restored the KET-induced increased levels of MPO activity in the PFC and the striatum, and protein carbonyls in the HPC. Post-KET treatment with RISP but not CBD decreased protein carbonyls in the PFC, and decreased the N/N concentration ratio in the HYP.

CONCLUSION

CBD restored the KET-induced decrease in rearing behavior without inducing an anhedonic-like phenotype as observed with RISP. CBD, and to a lesser extent RISP restored the oxidative stress and neuroinflammation elicited by KET in the striatum, HPC, and PFC. These findings support the possibility that the antipsychotic effects of CBD might be mediated by its antioxidant and anti-inflammatory effects.

Multi-Targeting Phytochemicals for Alzheimer's Disease

Alzheimer's disease (AD) is a type of neurodegenerative illness in which β-amyloid (Aβ) and tau protein accumulate in neurons in the form of tangles. The pathophysiological pathway of AD consists of Aβ-amyloid peptides, tau proteins, and oxidative stress in neurons and increased neuro-inflammatory response. Food and Drug Administration in the United States has authorized various drugs for the effective treatment of AD, which include galantamine, rivastigmine, donepezil, memantine, sodium oligomannate, lecanemab, and aducanumab. The major disadvantage of these drugs is that they only provide "symptomatic" relief. They are most effective in the early stages or for mild to moderate cases of the disease, but are not suitable for long-term use. Besides conventional therapies, phytochemicals have the potential to stop the progression of AD. According to research, the use of potential phytochemicals against AD has gained attention due to their potent anti-inflammatory, antioxidant, anti-hyperphosphorylation of the tau protein, metal chelation, and anti-amyloid properties. This study seeks to provide an up-to-date compilation of the most current and promising breakthroughs in AD therapy using phytochemicals. It could be concluded that phytochemicals light serve as an effective therapy for AD. However, more mechanistic investigations are needed to determine the clinical implications of phytochemicals in AD treatment.

CBD and the 5-HT1A receptor: A medicinal and pharmacological review

Cannabidiol (CBD), a phytocannabinoid, has emerged as a promising candidate for addressing a wide array of symptoms. It has the ability to bind to multiple proteins and receptors, including 5-HT1AR, transient receptor potential vanilloid 1 (TRPV1), and cannabinoid receptors. However, CBD's pharmacodynamic interaction with 5-HT1AR and its medicinal outcomes are still debated. This review explores recent literature to elucidate these questions, highlighting the neurotherapeutic outcomes of this pharmacodynamic interaction and proposing a signaling pathway underlying the mechanism by which CBD desensitizes 5-HT1AR signaling. A comprehensive survey of the literature underscores CBD's multifaceted neurotherapeutic effects, which include antidepressant, anxiolytic, neuroprotective, antipsychotic, antiemetic, anti-allodynic, anti-epileptic, anti-degenerative, and addiction-treating properties, attributable in part to its interactions with 5-HT1AR. Furthermore, evidence suggests that the pharmacodynamic interaction between CBD and 5-HT1AR is contingent upon dosage. Moreover, we propose that CBD can induce desensitization of 5-HT1AR via both homologous and heterologous mechanisms. Homologous desensitization involves the recruitment of G protein-coupled receptor kinase 2 (GRK2) and β-arrestin, leading to receptor endocytosis. In contrast, heterologous desensitization is mediated by an elevated intracellular calcium level or activation of protein kinases, such as c-Jun N-terminal kinase (JNK), through the activity of other receptors.

Cannabidiol/cannabidiolic acid-rich hemp (Cannabis sativa L.) extract attenuates cognitive impairments and glial activations in rats exposed to chronic stress

ETHNOPHARMACOLOGICAL RELEVANCE

Hemp (Cannabis sativa L.) is increasingly being recognized for its medicinal properties beside utilizing it for food, oil, and textile fibers. The high level of cannabidiol (CBD) content in hemp's flowers shows promising neuroprotective properties without causing psychotomimetic or addictive effects. Recently, products containing CBD and its precursor, cannabidiolic acid (CBDA), have been used to treat stress-related cognitive impairment. However, the therapeutic potential of hemp extract remains inadequately explored.

AIM OF THE STUDY

To investigate the effect of CBD/CBDA-rich hemp extract on learning and memory, neuroendocrine alterations, and hippocampal neuropathological changes in the chronic restraint stress model.

MATERIALS AND METHODS

Chronic restraint stress (CRS) was induced in male Wistar rats by immobilizing them in a restrainer for 6 h per day for 21 consecutive days. CBD/CBDA-rich hemp extract (10 and 30 mg/kg, intraperitoneal injection) was administered daily, 1 h before restraint. After the last day of CRS, behavioral tests for cognition were conducted using the Y-maze and object recognition tests. Serum corticosterone (CORT) levels were measured by ELISA. Histopathological changes, neuronal density, and the activation of microglia and astrocytes were visualized using cresyl violet and immunohistochemical staining.

RESULTS

A high dose of CBD/CBDA-rich hemp extract effectively ameliorated CRS-induced cognitive impairment and reversed HPA axis hyperactivity in CRS rats by reducing CORT levels and adrenal gland weight. Additionally, CBD/CBDA-rich hemp extract protected CRS-induced damage to hippocampal neurons. Further analysis showed that CBD/CBDA-rich hemp extract reduced specific markers of microglial activation (ionized calcium-binding adaptor molecule-1, Iba-1) and astrocytic structural protein (glial fibrillary acidic protein, GFAP) in CRS rats.

CONCLUSION

CBD/CBDA-rich hemp extracts remarkably reversed the stress-induced behavioral perturbations and hippocampal damage, suggesting its ameliorative effect on stress response.

Plant-derived compounds and neurodegenerative diseases: Different mechanisms of action with therapeutic potential

Neurodegenerative diseases are a group of disorders characterized by progressive degeneration of discrete groups of neurons causing severe disability. The main risk factor is age, hence their incidence is rapidly increasing worldwide due to the rise in life expectancy. Although the causes of the disease are not identified in about 90% of the cases, in the last decades there has been great progress in understanding the basis for neurodegeneration. Different pathological mechanisms including oxidative stress, mitochondrial dysfunction, alteration in proteostasis and inflammation have been addressed as important contributors to neuronal death. Despite our better understanding of the pathophysiology of these diseases, there is still no cure and available therapies only provide symptomatic relief. In an effort to discover new therapeutic approaches, natural products have aroused interest among researchers given their structural diversity and wide range of biological activities. In this review, we focus on three plant-derived compounds with promising neuroprotective potential that have been traditionally used by folk medicine: the flavonoid quercetin (QCT), the phytocannabinoid cannabidiol (CBD)and the tryptamine N,N-dimethyltryptamine (DMT). These compounds exert neuroprotective effects through different mechanisms of action, some overlapping, but each demonstrating a principal biological activity: QCT as an antioxidant, CBD as an anti-inflammatory, and DMT as a promoter of neuroplasticity. This review summarizes current knowledge on these activities, potential therapeutic benefits of these compounds and their limitations as candidates for neuroprotective therapies. We envision that treatments with QCT, CBD, and DMT could be effective either when combined or when targeting different stages of these diseases.

Cannabidiol-Induced Autophagy Ameliorates Tau Protein Clearance

Tau is a neuronal protein that confers stability to microtubules; however, its hyperphosphorylation and accumulation can lead to an impairment of protein degradation pathways, such as autophagy. Autophagy is a lysosomal catabolic process responsible for degrading cytosolic components, being essential for cellular homeostasis and survival. In this context, autophagy modulation has been postulated as a possible therapeutic target for the treatment of neurodegenerative diseases. Studies point to the modulatory and neuroprotective role of the cannabinoid system in neurodegenerative models and here it was investigated the effects of cannabidiol (CBD) on autophagy in a human neuroblastoma strain (SH-SY5Y) that overexpresses the EGFP-Tau WT (Wild Type) protein in an inducible Tet-On system way. The results demonstrated that CBD (100 nM and 10 µM) decreased the expression of AT8 and total tau proteins, activating autophagy, evidenced by increased expression of light chain 3-II (LC3-II) protein and formation of autophagosomes. Furthermore, the cannabinoid compounds CBD, ACEA (CB1 agonist) and GW-405,833 (CB2 agonist) decreased the fluorescence intensity of EGFP-Tau WT; and when chloroquine, an autophagic blocker, was used, there was a reversal in the fluorescence intensity of EGFP-Tau WT with CBD (1 and 10 µM) and GW-405,833 (2 µM), demonstrating the possible participation of autophagy in these groups. Thus, it was possible to conclude that CBD induced autophagy in EGFP-Tau WT cells which increased tau degradation, showing its possible neuroprotective role. Hence, this study may contribute to a better understanding of how cannabinoids can modulate autophagy and present a potential therapeutic target in a neurodegeneration model.

The synthetic cannabinoid WIN 55,212-2 attenuates cognitive and motor deficits and reduces amyloid load in 5XFAD Alzheimer mice

BACKGROUND

Alzheimer's disease (AD) is characterized by cognitive decline, with pathological features including amyloid β (Aβ) plaques and inflammation. Despite recent approvals of anti-amyloid antibodies, there remains a need for disease-modifying and easily accessible therapies. The endocannabinoid system presents a promising target for AD treatment, as it regulates various processes implicated in AD pathogenesis.

AIMS

This study assesses the effects of the synthetic cannabinoid WIN 55,212-2 on AD pathology and behavior deficits in aged 5XFAD mice, a well-established AD model.

METHODS

Male 9-month-old 5XFAD mice received either 0.2 mg/kg WIN 55,212-2 or a vehicle solution for 42 days. Memory, anxiety, and motor tests were conducted at 10 months to identify potential changes in behavior and cognition following WIN 55,212-2 treatment. Additionally, the effects of prolonged WIN 55,212-2 treatment on Aβ pathology and neuroinflammation in the brain were quantified immunohistochemically.

RESULTS

Therapeutic WIN 55,212-2 treatment improved the motor performance of 5XFAD mice on the rotarod and rescued memory deficits in the water maze. However, WIN 55,212-2 treatment did not significantly affect anxiety-like behavior in 5XFAD mice. Additionally, prolonged treatment with WIN 55,212-2 reduced Aβ plaque pathology and astrogliosis in the cortex and hippocampus.

CONCLUSIONS

This study highlights the therapeutic potential of WIN 55,212-2 in AD by ameliorating cognitive and motor deficits and reducing neuropathology. These findings support a cannabinoid-based therapy as a promising strategy for AD treatment, with WIN 55,212-2 emerging as a potential candidate.

Cannabidiol in Foods and Food Supplements: Evaluation of Health Risks and Health Claims

BACKGROUND

Cannabidiol (CBD) is a cannabinoid present in the hemp plant (Cannabis sativa L.). Non-medicinal CBD oils with typically 5-40% CBD are advertised for various alleged positive health effects. While such foodstuffs containing cannabinoids are covered by the Novel Food Regulation in the European Union (EU), none of these products have yet been authorized. Nevertheless, they continue to be available on the European market.

METHODS

The Permanent Senate Commission on Food Safety (SKLM) of the German Research Foundation (DFG) reviewed the currently available data on adverse and potential beneficial effects of CBD in the dose range relevant for foods.

RESULTS

Increased liver enzyme activities were observed in healthy volunteers following administration of 4.3 mg CBD/kg bw/day and higher for 3-4 weeks. As lower doses were not tested, a no observed adverse effect level (NOAEL) could not be derived, and the dose of 4.3 mg/kg bw/day was identified as the lowest observed adverse effect level (LOAEL). Based on the CBD content and dose recommendations of CBD products on the market, the SKLM considered several exposure scenarios and concluded that the LOAEL for liver toxicity may be easily reached, e.g., via consumption of 30 drops of an oil containing 20% CBD, or even exceeded. A critical evaluation of the available data on potential beneficial health effects of CBD in the dose range at or below the LOAEL of 4.3 mg/kg bw/day revealed no scientific evidence that would substantiate health claims, e.g., in relation to physical performance, the cardiovascular, immune, and nervous system, anxiety, relaxation, stress, sleep, pain, or menstrual health.

CONCLUSIONS

The SKLM concluded that consumption of CBD-containing foods/food supplements may not provide substantiated health benefits and may even pose a health risk to consumers.

Penetratin and Mannose-Functionalized Cannabidiol Lipid Nanoparticles Encapsulating the BDNF Gene Reduce Amyloid-Induced Inflammation

Inflammation is emerging as a critical player in the disease progression of Alzheimer's disease (AD) by its interaction with amyloid beta plaques in a feed-forward loop. There is also a decline in the nourishment and enriching neurotrophic factor, brain-derived neurotrophic factor (BDNF), in the brain. Therefore, supplementing the brain with BDNF by gene delivery and delivering the anti-inflammatory agent, cannabidiol (CBD) in this case, to mitigate inflammation-induced disease cascade offers an attractive treatment strategy. To achieve the brain localization of CBD and pBDNF, lipid nanoparticles (LNPs) functionalized with mannose and penetratin were utilized. CBD and pBDNF were successfully encapsulated in the LNPs (more than 80%) with a size less than 180 nm, polydispersity index less than 0.25, and zeta potential of 23 mV. CBD was released from the formulation over a period of a week. The dual-functionalized LNPs demonstrated higher cellular uptake of CBD and expressed a significantly higher amount of BDNF (p-value <0.05) after transfection than their nonmodified counterparts in four brain cell lines, i.e., brain endothelial cells (b.END3), immortalized microglia cells (IMGs), primary astrocytes, and primary neurons. Similarly, the permeation of CBD through the dual-modified LNPs across the in vitro coculture blood-brain barrier model was significantly higher (p-value <0.05) compared to free CBD or nonfunctionalized nanoparticles. The LNPs demonstrated anti-inflammatory activity against lipopolysaccharides and human amyloid beta1-42 oligomer induction as they reduced the protein and mRNA expression of pro-inflammatory cytokines TNF-α (p < 0.05) and IL-1β (p < 0.05) in IMG cells. In summary, the penetratin and mannose-functionalized LNPs encapsulating CBD and pBDNF could serve as a promising therapy in AD, requiring further validation in animal models.

Chronic exposure to a synthetic cannabinoid improves cognition and increases locomotor activity in Tg4-42 Alzheimer's disease mice

Background

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by cognitive decline and behavior impairments. Despite recent approvals of anti-amyloid antibodies, there remains a need for disease modifying and easily accessible therapies. Emerging evidence suggests that targeting the endocannabinoid system may hold promise for AD therapy as it plays a crucial role in different physiological processes, including learning, memory and anxiety, as well as inflammatory and immune responses.

Objective

In this study, we investigated the therapeutic potential of the synthetic cannabinoid WIN 55,212-2 on memory deficits in Tg4-42 transgenic mice.

Methods

Tg4-42 mice were assigned to two treatment groups to investigate the preventive effects of WIN 55,212-2 after a prolonged washout period, as well as the therapeutic effects of WIN 55,212-2 on behavior. Furthermore, the effects of WIN 55,212-2 treatment on AD pathology, including inflammation, amyloid-β load, neurogenesis, and brain glucose metabolism, were evaluated.

Results

Therapeutic WIN 55,212-2 treatment rescued recognition memory and spatial reference deficits in Tg4-42 mice. Furthermore, therapeutic WIN 55,212-2 administration improved motor performance. In addition, preventative WIN 55,212-2 treatment rescued spatial learning and reference memory deficits. Importantly, WIN 55,212-2 treatment did not affect anxiety-like behavior. However, therapeutic and preventative WIN 55,212-2 treatment resulted in an increase locomotor activity and swimming speed in Tg4-42 mice. WIN-treatment reduced microgliosis in the hippocampus of preventively treated mice and rescued brain glucose metabolism in therapeutically treated Tg4-42 mice.

Conclusions

Our findings emphasize the therapeutic promise of the synthetic cannabinoid WIN 55,212-2 in alleviating behavioral and cognitive deficits linked to AD.

Evaluation of the Efficacy of a Full-Spectrum Low-THC Cannabis Plant Extract Using In Vitro Models of Inflammation and Excitotoxicity

Evidence has accumulated that Cannabis-derived compounds have the potential to treat neuroinflammatory changes present in neurodevelopmental conditions such as autism spectrum disorder. However, research is needed on the specific brain health benefits of strains of whole Cannabis extract that are ready for commercial production. Here, we explore the anti-inflammatory and neuroprotective effects of NTI-164, a genetically unique high-cannabidiol (CBD), low-Δ9-tetrahydrocannabinol extract, and also CBD alone on BV-2 microglia and SHSY-5Y neurons. Inflammation-induced up-regulation of microglial inflammatory markers was significantly attenuated by NTI-164, but not by CBD. NTI-164 promoted undifferentiated neuron proliferation and differentiated neuron survival under excitotoxic conditions. These effects suggest the potential for NTI-164 as a treatment for neuropathologies.

Potential analgesic effect of a novel cannabidiol nanocrystals powder for the treatment of neuropathic pain

BACKGROUND

The current analgesics often prevent patients from getting effective treatment due to their adverse effects. Cannabidiol (CBD) is well tolerated, has few side effects and has been extensively investigated in analgesia. However, its oral bioavailability is extremely low. In order to solve this problem, we developed the cannabidiol nanocrystals (CBD-NC) in the earlier stage.

METHODS

In this study, we evaluated the nociceptive behaviours associated with neuropathic pain (NP) induced by the spared nerve injury (SNI) model. Assessment of pain threshold was evaluated by paw withdraw threshold (PWT) and paw withdrawal latency (PWL). The improving effect on the motor dysfunction was determined by rota-rod testing. To assess the neuroprotective effect, nerve demyelination and expression of peripheral myelin protein PMP22 were measured with myelin sheath staining and western blotting. Protein expressions in microglia of spinal cord were tested by western blot to explore the underlying mechanism.

RESULTS

Compared with the CBD oil solution, CBD-NC significantly reduced mechanical allodynia and thermal hyperalgesia in rats. CBD-NC could improve motor dysfunction induced by SNI in rats, significantly reverse the demyelination and increase the expression of the marker protein of peripheral myelin. Underlying spinal analgesic mechanism of microglia and related factors were preliminarily confirmed.

CONCLUSIONS

CBD-NC administration is an effective treatment for NP associated with SNI, and the analgesic effect of CBD-NC was significantly better than that of CBD oil sol. By contrast, CBD-NC has a fast-acting and long-term effect in the treatment of NP. Our study further supports the potential therapeutic effect of CBD-NC on NP.

SIGNIFICANCE

The absolute bioavailability of the CBD-NC intramuscular injection formulation can reach 203.31%, which can solve the problem of low oral bioavailability. This research evaluated the therapeutic effect of CBD-NC on NP associated with the SNI model for the first time. All available date showed that whatever the analgesic or neuroprotective effect of CBD-NC, it was significantly better than that of CBD oil sol., which was consistent with the results of the pharmacokinetic. This research supports the initiation of more trials testing the efficacy of CBD-NC for treating NP.

CBD's potential impact on Parkinson's disease: An updated overview

Background

Parkinson's disease (PD) is primarily known as a motor disorder; however, its debilitating non-motor symptoms have a significant impact on patients' quality of life. The current standard treatment, l-DOPA, is used to relieve motor symptoms, but prolonged use is often associated with severe side effects. This creates an urgent need for effective alternatives targeting both motor and non-motor symptoms.

Objectives

Over the past decade, Cannabis sativa and its cannabinoids have been widely studied across various health conditions. Among these compounds, cannabidiol (CBD), a non-psychoactive component, is garnering growing interest due to its multi-targeted pleiotropic properties. This work aims to provide a comprehensive overview of CBD's efficacy in PD.

Methods

This review compiles data on both motor and non-motor symptoms of PD, integrating results from preclinical animal studies and available clinical trials.

Results

Preclinical research has demonstrated promising results regarding CBD's potential benefits in PD; however, the total number of clinical trials is limited (with only seven studies to date), making it difficult to draw definitive conclusions on its efficacy.

Conclusions

While preclinical findings suggest that CBD may have therapeutic potential in PD, the limited number of clinical trials highlights the need for further research. This review emphasizes the gaps that need to be addressed in future studies to fully understand CBD's role in treating both motor and non-motor symptoms of PD.

Unveiling the Potential of Phytocannabinoids: Exploring Marijuana's Lesser-Known Constituents for Neurological Disorders

Cannabis sativa is known for producing over 120 distinct phytocannabinoids, with Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) being the most prominent, primarily in their acidic forms. Beyond Δ9-THC and CBD, a wide array of lesser-known phytocannabinoids, along with terpenes, flavonoids, and alkaloids, demonstrate diverse pharmacological activities, interacting with the endocannabinoid system (eCB) and other biological pathways. These compounds, characterized by phenolic structures and hydroxyl groups, possess lipophilic properties, allowing them to cross the blood-brain barrier (BBB) effectively. Notably, their antioxidant, anti-inflammatory, and neuro-modulatory effects position them as promising agents in treating neurodegenerative disorders. While research has extensively examined the neuropsychiatric and neuroprotective effects of Δ9-THC, other minor phytocannabinoids remain underexplored. Due to the well-established neuroprotective potential of CBD, there is growing interest in the therapeutic benefits of non-psychotropic minor phytocannabinoids (NMPs) in brain disorders. This review highlights the emerging research on these lesser-known compounds and their neuroprotective potential. It offers insights into their therapeutic applications across various major neurological conditions.

A systematic study of molecular targets of cannabidiol in Alzheimer's disease

Background

Alzheimer's disease (AD) is a prevalent, incurable, and chronic neurodegenerative condition characterized by the accumulation of amyloid-β protein (Aβ), disrupting various bodily systems. Despite the lack of a cure, phenolic compounds like cannabidiol (CBD), a non-psychoactive component of cannabis, have emerged as potential therapeutic agents for AD.

Objective

This systematic review explores the impact of different types of cannabidiol on AD, unveiling their neuroprotective mechanisms.

Methods

The research used PubMed, Scopus, and Web of Science databases with keywords like "Alzheimer's disease" and "Cannabidiol." Studies were evaluated based on title, abstract, and relevance to treating AD with CBD. No restrictions on research type or publication year. Excluded were hypothesis papers, reviews, books, unavailable articles, etc.

Results

Microsoft Excel identified 551 articles, with 92 included in the study, but only 22 were thoroughly evaluated. In-vivo and in-silico studies indicate that CBD may disrupt Aβ42, reduce pro-inflammatory molecule release, prevent reactive oxygen species formation, inhibit lipid oxidation, and counteract Aβ-induced increases in intracellular calcium, thereby protecting neurons from apoptosis.

Conclusions

In summary, the study indicates that CBD and its analogs reduce the production of Aβ42. Overall, these findings support the potential of CBD in alleviating the underlying pathology and symptoms associated with AD, underscoring the crucial need for further rigorous scientific investigation to elucidate the therapeutic applications and mechanisms of CBD in AD.

Effects of Chronic, Low-Dose Cannabinoids, Cannabidiol, Delta-9-Tetrahydrocannabinol and a Combination of Both, on Amyloid Pathology in the 5xFAD Mouse Model of Alzheimer's Disease

Background: There is an urgent need for novel therapies to treat Alzheimer's disease. Among others, the use of cannabinoids such as delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) has been proposed as a putative approach based on their anti-inflammatory effects. Methods: The present work was designed to explore the effects of chronic (28 days) treatment with low doses of cannabinoids: CBD (0.273 mg/kg), THC (0.205 mg/kg) or a combination of both (CBD:THC; 0.273 mg/kg:0.205 mg/kg) in the 5xFAD mouse model of AD. Results: Our data revealed that THC-treated 5xFAD mice (but not other treatment groups) exhibited anxiogenic and depressant-like behavior. A significant improvement in spatial memory was observed only in the CBD:THC-treated group. Interestingly, all cannabinoid-treated groups showed significantly increased cortical levels of the insoluble form of beta amyloid 1-42. These effects were not accompanied by changes in molecular parameters of inflammation at the mRNA or protein level. Conclusions: These data reveal differential effects of chronic, low-dose cannabinoids and point to a role of these cannabinoids in the processing of amyloid peptides in the brains of 5xFAD mice.

Cannabis Use and Cannabidiol Modulate HIV-Induced Alterations in TREM2 Expression: Implications for Age-Related Neuropathogenesis

Triggering receptor expressed on myeloid cells 2 (TREM2) is involved in neuroinflammation and HIV-associated neurocognitive impairment (NCI). People with HIV (PWH) using cannabis exhibit lower inflammation and neurological disorders. We hypothesized that TREM2 dysfunction mediates HIV neuropathogenesis and can be reversed by cannabinoids. EcoHIV-infected wildtype (WT) and TREM2R47H mutant mice were used to study HIV's impact on TREM2 and behavior. TREM2 and related gene expressions were examined in monocyte-derived macrophages (MDMs) from PWH (n = 42) and people without HIV (PWoH; n = 19) with varying cannabis use via RNA sequencing and qPCR. Differences in membrane-bound and soluble TREM2 (sTREM2) were evaluated using immunocytochemistry (ICC) and ELISA. EcoHIV increased immature and C-terminal fragment forms of TREM2 in WT mice but not in TREM2R47H mice, with increased IBA1 protein in TREM2R47H hippocampi, correlating with worse memory test performance. TREM2 mRNA levels increased with age in PWoH but not in PWH. Cannabidiol (CBD) treatment increased TREM2 mRNA alone and with IL1β. RNA-seq showed the upregulation of TREM2-related transcripts in cannabis-using PWH compared to naïve controls. IL1β increased sTREM2 and reduced membrane-bound TREM2, effects partially reversed by CBD. These findings suggest HIV affects TREM2 expression modulated by cannabis and CBD, offering insights for therapeutic strategies.

Phytocannabinoids in neuromodulation: From omics to epigenetics

BACKGROUND

Recent developments in metabolomics, transcriptomic and epigenetics open up new horizons regarding the pharmacological understanding of phytocannabinoids as neuromodulators in treating anxiety, depression, epilepsy, Alzheimer's, Parkinson's disease and autism.

METHODS

The present review is an extensive search in public databases, such as Google Scholar, Scopus, the Web of Science, and PubMed, to collect all the literature about the neurobiological roles of cannabis extract, cannabidiol, 9-tetrahydrocannabinol specially focused on metabolomics, transcriptomic, epigenetic, mechanism of action, in different cell lines, induced animal models and clinical trials. We used bioinformatics, network pharmacology and enrichment analysis to understand the effect of phytocannabinoids in neuromodulation.

RESULTS

Cannabidomics studies show wide variability of metabolites across different strains and varieties, which determine their medicinal and abusive usage, which is very important for its quality control and regulation. CB receptors interact with other compounds besides cannabidiol and Δ9-tetrahydrocannabinol, like cannabinol and Δ8-tetrahydrocannabinol. Phytocannabinoids interact with cannabinoid and non-cannabinoid receptors (GPCR, ion channels, and PPAR) to improve various neurodegenerative diseases. However, its abuse because of THC is also a problem found across different epigenetic and transcriptomic studies. Network enrichment analysis shows CNR1 expression in the brain and its interacting genes involve different pathways such as Rap1 signalling, dopaminergic synapse, and relaxin signalling. CBD protects against diseases like epilepsy, depression, and Parkinson's by modifying DNA and mitochondrial DNA in the hippocampus. Network pharmacology analysis of 8 phytocannabinoids revealed an interaction with 10 (out of 60) targets related to neurodegenerative diseases, with enrichment of ErbB and PI3K-Akt signalling pathways which helps in ameliorating neuro-inflammation in various neurodegenerative diseases. The effects of phytocannabinoids vary across sex, disease state, and age which suggests the importance of a personalized medicine approach for better success.

CONCLUSIONS

Phytocannabinoids present a range of promising neuromodulatory effects. It holds promise if utilized in a strategic way towards personalized neuropsychiatric treatment. However, just like any drug irrational usage may lead to unforeseen negative effects. Exploring neuro-epigenetics and systems pharmacology of major and minor phytocannabinoid combinations can lead to success.

Cannabidiol and Alzheimer's disease

Alzheimer's disease (AD) stands as the most prevalent form of neuropsychiatric disorder among the elderly population, impacting a minimum of 50 million individuals worldwide. Current pharmacological treatments rely on the prescribing cholinesterase inhibitors and memantine. However,recently anecdotal findings based on low-quality real-world data had prompted physicians, patients, and their relatives to consider the use of cannabinoids, especially Cannabidiol (CBD), for alleviating of AD symptoms. CBD the primary non-psychotomimetic compound found in the Cannabis sp. plant, exhibits promising therapeutic potential across various clinical contexts. Pre-clinical and in vitro studies indicate that CBD could mitigate cognitive decline and amyloid-beta-induced neurodegeneration by modulating oxidative stress and neuroinflammation. In addition, CBD demonstrates significant effects in promoting neuroplasticity, particularly in brain regions such as the hippocampus. However, the available clinical evidence presents conflicting results, and no randomized placebo-controlled trials have been published to date. In conclusion, although pre-clinical and in vitro studies offer encouraging insights into the potential benefits of CBD in AD models, new and well-designed clinical trials are imperative to ascertain the clinical relevance of CBD use in the management of AD symptoms, especially in comparison to conventional treatments.

Interplay among Oxidative Stress, Autophagy, and the Endocannabinoid System in Neurodegenerative Diseases: Role of the Nrf2- p62/SQSTM1 Pathway and Nutraceutical Activation

The onset of neurodegenerative diseases involves a complex interplay of pathological mechanisms, including protein aggregation, oxidative stress, and impaired autophagy. This review focuses on the intricate connection between oxidative stress and autophagy in neurodegenerative disorders, highlighting autophagy as pivotal in disease pathogenesis. Reactive oxygen species (ROS) play dual roles in cellular homeostasis and autophagy regulation, with disruptions of redox signaling contributing to neurodegeneration. The activation of the Nrf2 pathway represents a critical antioxidant mechanism, while autophagy maintains cellular homeostasis by degrading altered cell components. The interaction among p62/SQSTM1, Nrf2, and Keap1 forms a regulatory pathway essential for cellular stress response, whose dysregulation leads to impaired autophagy and aggregate accumulation. Targeting the Nrf2-p62/SQSTM1 pathway holds promise for therapeutic intervention, mitigating oxidative stress and preserving cellular functions. Additionally, this review explores the potential synergy between the endocannabinoid system and Nrf2 signaling for neuroprotection. Further research is needed to elucidate the involved molecular mechanisms and develop effective therapeutic strategies against neurodegeneration.

Cannabidiol and its application in the treatment of oral diseases: therapeutic potentials, routes of administration and prospects

Cannabidiol (CBD), one of the most important active ingredients in cannabis, has been reported to have some pharmacological effects such as antibacterial and analgesic effects, and to have therapeutic potential in the treatment of oral diseases such as oral cancer, gingivitis and periodontal diseases. However, there is a lack of relevant systematic research and reviews. Therefore, based on the etiology and clinical symptoms of several common oral diseases, this paper focuses on the therapeutic potential of CBD in periodontal diseases, pulp diseases, oral mucosal diseases, oral cancer and temporomandibular joint diseases. The pharmacological effects of CBD and the distribution and function of its receptors in the oral cavity are also summarized. In order to provide reference for future research and further clinical application of CBD, we also summarize several possible routes of administration and corresponding characteristics. Finally, the challenges faced while applying CBD clinically and possible solutions are discussed, and we also look to the future.

The Influence of an Acute Administration of Cannabidiol or Rivastigmine, Alone and in Combination, on Scopolamine-Provoked Memory Impairment in the Passive Avoidance Test in Mice

Memory is one of the most important abilities of our brain. The process of memory and learning is necessary for the proper existence of humans in the surrounding environment. However, sometimes there are unfavourable changes in the functioning of the brain and memory deficits occur, which may be associated with various diseases. Disturbances in the cholinergic system lead to abnormalities in memory functioning and are an essential part of clinical symptoms of many neurodegenerative diseases. However, their treatment is difficult and still unsatisfactory; thus, it is necessary to search for new drugs and their targets, being an alternative method of mono- or polypharmacotherapy. One of the possible strategies for the modulation of memory-related cognitive disorders is connected with the endocannabinoid system (ECS). The aim of the present study was to determine for the first time the effect of administration of natural cannabinoid compound (cannabidiol, CBD) and rivastigmine alone and in combination on the memory disorders connected with cholinergic dysfunctions in mice, provoked by using an antagonist of muscarinic cholinergic receptor-scopolamine. To assess and understand the memory-related effects in animals, we used the passive avoidance (PA) test, commonly used to examine the different stages of memory. An acute administration of CBD (1 mg/kg) or rivastigmine (0.5 mg/kg) significantly affected changes in scopolamine-induced disturbances in three different memory stages (acquisition, consolidation, and retrieval). Interestingly, co-administration of CBD (1 mg/kg) and rivastigmine (0.5 mg/kg) also attenuated memory impairment provoked by scopolamine (1 mg/kg) injection in the PA test in mice, but at a much greater extent than administered alone. The combination therapy of these two compounds, CBD and rivastigmine, appears to be more beneficial than substances administered alone in reducing scopolamine-induced cognitive impairment. This polytherapy seems to be favourable in the pharmacotherapy of various cognitive disorders, especially those in which cholinergic pathways are implicated.

Endocannabinoid System Changes throughout Life: Implications and Therapeutic Potential for Autism, ADHD, and Alzheimer's Disease

The endocannabinoid system has been linked to various physiological and pathological processes, because it plays a neuromodulator role in the central nervous system. In this sense, cannabinoids have been used off-label for neurodevelopmental disorders, such as autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHA), as well as in Alzheimer's disease (AD), a more prevalent neurodegenerative disease. Thus, this study aims, through a comprehensive literature review, to arrive at a better understanding of the impact of cannabinoids in the therapeutic treatment of patients with ASD, ADHD, and Alzheimer's disease (AD). Overall, cannabis products rich in CBD displayed a higher therapeutic potential for ASD children, while cannabis products rich in THC have been tested more for AD therapy. For ADHD, the clinical studies are incipient and inconclusive, but promising. In general, the main limitations of the clinical studies are the lack of standardization of the cannabis-based products consumed by the participants, a lack of scientific rigor, and the small number of participants.

Neuroprotective Effect of a Pharmaceutical Extract of Cannabis with High Content on CBD Against Rotenone in Primary Cerebellar Granule Cell Cultures and the Relevance of Formulations

Introduction: Preclinical research supports the benefits of pharmaceutical cannabis-based extracts for treating different medical conditions (e.g., epilepsy); however, their neuroprotective potential has not been widely investigated. Materials and Methods: Using primary cultures of cerebellar granule cells, we evaluated the neuroprotective activity of Epifractan (EPI), a cannabis-based medicinal extract containing a high level of cannabidiol (CBD), components like terpenoids and flavonoids, trace levels of Δ9-tetrahydrocannabinol, and the acid form of CBD. We determined the ability of EPI to counteract the rotenone-induced neurotoxicity by analyzing cell viability and morphology of neurons and astrocytes by immunocytochemical assays. The effect of EPI was compared with XALEX, a plant-derived and highly purified CBD formulation (XAL), and pure CBD crystals (CBD). Results: The results revealed that EPI induced a significant reduction in the rotenone-induced neurotoxicity in a wide range of concentrations without causing neurotoxicity per se. EPI showed a similar effect to XAL suggesting that no additive or synergistic interactions between individual substances present in EPI occurred. In contrast, CBD did show a different profile to EPI and XAL because a neurotoxic effect per se was observed at higher concentrations assayed. Medium-chain triglyceride oil used in EPI formulation could explain this difference. Conclusion: Our data support a neuroprotective effect of EPI that may provide neuroprotection in different neurodegenerative processes. The results highlight the role of CBD as the active component of EPI but also support the need for an appropriate formulation to dilute pharmaceutical cannabis-based products that could be critical to avoid neurotoxicity at very high doses.

Natural Antioxidants: An Effective Strategy for the Treatment of Alzheimer's Disease at the Early Stage

The critical role of oxidative stress in Alzheimer's disease (AD) has been recognized by researchers recently, and natural antioxidants have been demonstrated to have anti-AD activity in animal models, such as Ginkgo biloba extract, soy isoflavones, lycopene, and so on. This paper summarized these natural antioxidants and points out that natural antioxidants always have multiple advantages which are help to deal with AD, such as clearing free radicals, regulating signal transduction, protecting mitochondrial function, and synaptic plasticity. Based on the available data, we have created a relatively complete pathway map of reactive oxygen species (ROS) and AD-related targets and concluded that oxidative stress caused by ROS is the core of AD pathogenesis. In the prospect, we introduced the concept of a combined therapeutic strategy, termed "Antioxidant-Promoting Synaptic Remodeling," highlighting the integration of antioxidant interventions with synaptic remodeling approaches as a novel avenue for therapeutic exploration.

How Biodegradable Polymers Can be Effective Drug Delivery Systems for Cannabinoids? Prospectives and Challenges

Cannabinoids are compounds found in and derived from the Cannabis plants that have become increasingly recognised as significant modulating factors of physiological mechanisms and inflammatory reactions of the organism, thus inevitably affecting maintenance of homeostasis. Medical Cannabis popularity has surged since its legal regulation growing around the world. Numerous promising discoveries bring more data on cannabinoids' pharmacological characteristics and therapeutic applications. Given the current surge in interest in the medical use of cannabinoids, there is an urgent need for an effective method of their administration. Surpassing low bioavailability, low water solubility, and instability became an important milestone in the advancement of cannabinoids in pharmaceutical applications. The numerous uses of cannabinoids in clinical practice remain restricted by limited administration alternatives, but there is hope when biodegradable polymers are taken into account. The primary objective of this review is to highlight the wide range of indications for which cannabinoids may be used, as well as the polymeric carriers that enhance their effectiveness. The current review described a wide range of therapeutic applications of cannabinoids, including pain management, neurological and sleep disorders, anxiety, and cancer treatment. The use of these compounds was further examined in the area of dermatology and cosmetology. Finally, with the use of biodegradable polymer-based drug delivery systems (DDSs), it was demonstrated that cannabinoids can be delivered specifically to the intended site while also improving the drug's physicochemical properties, emphasizing their utility. Nevertheless, additional clinical trials on novel cannabinoids' formulations are required, as their full spectrum therapeutical potential is yet to be unravelled.

Modulation of Oxidative Stress and Neuroinflammation by Cannabidiol (CBD): Promising Targets for the Treatment of Alzheimer's Disease

Alzheimer's disease (AD) is a progressive neurodegenerative disease and the most common form of dementia globally. Although the direct cause of AD remains under debate, neuroinflammation and oxidative stress are critical components in its pathogenesis and progression. As a result, compounds like cannabidiol (CBD) are being increasingly investigated for their ability to provide antioxidant and anti-inflammatory neuroprotection. CBD is the primary non-psychotropic phytocannabinoid derived from Cannabis sativa. It has been found to provide beneficial outcomes in a variety of medical conditions and is gaining increasing attention for its potential therapeutic application in AD. CBD is not psychoactive and its lipophilic nature allows its rapid distribution throughout the body, including across the blood-brain barrier (BBB). CBD also possesses anti-inflammatory, antioxidant, and neuroprotective properties, making it a viable candidate for AD treatment. This review outlines CBD's mechanism of action, the role of oxidative stress and neuroinflammation in AD, and the effectiveness and limitations of CBD in preclinical models of AD.

Novel pyrrole based CB2 agonists: New insights on CB2 receptor role in regulating neurotransmitters' tone

The cannabinoid system is one of the most investigated neuromodulatory systems because of its involvement in multiple pathologies such as cancer, inflammation, and psychiatric diseases. Recently, the CB2 receptor has gained increased attention considering its crucial role in modulating neuroinflammation in several pathological conditions like neurodegenerative diseases. Here we describe the rational design of pyrrole-based analogues, which led to a potent and pharmacokinetically suitable CB2 full agonist particularly effective in improving cognitive functions in a scopolamine-induced amnesia murine model. Therefore, we extended our study by investigating the interconnection between CB2 activation and neurotransmission in this experimental paradigm. To this purpose, we performed a MALDI imaging analysis on mice brains, observing that the administration of our lead compound was able to revert the effect of scopolamine on different neurotransmitter tones, such as acetylcholine, serotonin, and GABA, shedding light on important networks not fully explored, so far.

A Novel Anti-Inflammatory Formulation Comprising Celecoxib and Cannabidiol Exerts Antidepressant and Anxiolytic Effects

Background: Ample research shows that anti-inflammatory drugs, particularly celecoxib, exert antidepressant effects, especially in patients with microglia activation. However, substantial cardiovascular adverse effects limit celecoxib's usefulness. Given that cannabidiol (CBD) exerts anti-inflammatory, microglia-suppressive, and antidepressant effects, we hypothesized that it may potentiate the therapeutic effects of celecoxib. Methods: The effects of celecoxib, CBD, and their combination were examined in murine models of antidepressant- and anxiolytic-like behavioral responsiveness, including the forced swim test (FST), elevated plus maze (EPM), lipopolysaccharide (LPS)-induced neuroinflammation, and chronic social defeat stress (CSDS), as well as in microglia cell cultures. Results: Acute administration of a combination of celecoxib plus CBD, at doses that had no effects by themselves (10 and 5 mg/kg, respectively), produced significant antidepressant- and anxiolytic-like effects in the FST and EPM, in male and female mice. In the LPS model, combinations of celecoxib (10 or 20 mg/kg) plus CBD (30 mg/kg) reversed the anxiety-like behavior in the open-field test (OFT) and anhedonia in the sucrose preference test (SPT), with minimal effects of celecoxib or CBD by themselves. In the CSDS paradigm, a combination of celecoxib plus CBD (each at 30 mg/kg) reversed the deficits in the OFT, EPM, social exploration, and SPT, whereas celecoxib or CBD by themselves had partial effects. In BV2 microglia cultures stimulated with LPS or α-synuclein, CBD markedly potentiated the suppressive effects of celecoxib over TNFα (tumor necrosis factor-α) and IL (interleukin)-1β secretion. Conclusions: Combinations of celecoxib plus CBD produce efficacious antidepressant- and anxiolytic-like effects, which may depend on their synergistic microglia-suppressive effects.

Impact of cannabidiol on brain glucose metabolism of C57Bl/6 male mice previously exposed to cocaine

Despite evidence of the beneficial effects of cannabidiol (CBD) in animal models of cocaine use disorder (CUD), CBD neuronal mechanisms remain poorly understood. This study investigated the effects of CBD treatment on brain glucose metabolism, in a CUD animal model, using [18F]FDG positron emission tomography (PET). Male C57Bl/6 mice were injected with cocaine (20 mg/kg, i.p.) every other day for 9 days, followed by 8 days of CBD administration (30 mg/kg, i.p.). After 48 h, animals were challenged with cocaine. Control animals received saline/vehicle. [18F]FDG PET was performed at four time points: baseline, last day of sensitization, last day of withdrawal/CBD treatment, and challenge. Subsequently, the animals were euthanized and immunohistochemistry was performed on the hippocampus and amygdala to assess the CB1 receptors, neuronal nuclear protein, microglia (Iba1), and astrocytes (GFAP). Results showed that cocaine administration increased [18F]FDG uptake following sensitization. CBD treatment also increased [18F]FDG uptake in both saline and cocaine groups. However, animals that were sensitized and challenged with cocaine, and those receiving only an acute cocaine injection during the challenge phase, did not exhibit increased [18F]FDG uptake when treated with CBD. Furthermore, CBD induced modifications in the integrated density of NeuN, Iba, GFAP, and CB1R in the hippocampus and amygdala. This is the first study addressing the impact of CBD on brain glucose metabolism in a preclinical model of CUD using PET. Our findings suggest that CBD disrupts cocaine-induced changes in brain energy consumption and activity, which might be correlated with alterations in neuronal and glial function.

A narrative review of the therapeutic and remedial prospects of cannabidiol with emphasis on neurological and neuropsychiatric disorders

BACKGROUND

The treatment of diverse diseases using plant-derived products is actively encouraged. In the past few years, cannabidiol (CBD) has emerged as a potent cannabis-derived drug capable of managing various debilitating neurological infections, diseases, and their associated complications. CBD has demonstrated anti-inflammatory and curative effects in neuropathological conditions, and it exhibits therapeutic, apoptotic, anxiolytic, and neuroprotective properties. However, more information on the reactions and ability of CBD to alleviate brain-related disorders and the neuroinflammation that accompanies them is needed.

MAIN BODY

This narrative review deliberates on the therapeutic and remedial prospects of CBD with an emphasis on neurological and neuropsychiatric disorders. An extensive literature search followed several scoping searches on available online databases such as PubMed, Web of Science, and Scopus with the main keywords: CBD, pro-inflammatory cytokines, and cannabinoids. After a purposive screening of the retrieved papers, 170 (41%) of the articles (published in English) aligned with the objective of this study and retained for inclusion.

CONCLUSION

CBD is an antagonist against pro-inflammatory cytokines and the cytokine storm associated with neurological infections/disorders. CBD regulates adenosine/oxidative stress and aids the downregulation of TNF-α, restoration of BDNF mRNA expression, and recovery of serotonin levels. Thus, CBD is involved in immune suppression and anti-inflammation. Understanding the metabolites associated with response to CBD is imperative to understand the phenotype. We propose that metabolomics will be the next scientific frontier that will reveal novel information on CBD's therapeutic tendencies in neurological/neuropsychiatric disorders.

Long-term Effects of Cannabidiol and/or Fentanyl Exposure in Rats Submitted to Neonatal Pain

The current study aimed to evaluate anxiety behavior, hippocampal ionized calcium-binding adaptor molecule 1 (Iba1) and cannabinoid receptor 1 (CB1) gene expression, and nociceptive response in adulthood after a combination of fentanyl and cannabidiol (CBD) for nociceptive stimuli induced during the first week of life in rats. Complete Freund's adjuvant-induced inflammatory nociceptive insult on postnatal day (PN) 1 and PN3. Both fentanyl and CBD were used alone or in combination from PN1 to PN7. Behavioral and nociceptive tests were performed at PN60 and PN62. The expression of the microglial calcium-binding proteins Iba1 and CB1 was detected in the hippocampus using reverse Quantitative polymerase chain reaction (qPCR) and immunohistochemistry. Our results suggest that the anxiety behavior response and immune activation in adult life depend on the CBD dose combined with fentanyl for the nociceptive stimuli induced during the first week of life. Treatment of neonatal nociceptive insult with CBD and opioids showed significant dose-dependent and male-female differences. The increased gene expression in the hippocampus of the analyzed cannabinoid gene supports this data. In addition, treatment with fentanyl led to an increase in CB1 protein expression. Moreover, the expression of Iba1 varied according to the administered dose of CBD and may or may not be associated with the opioid. A lower dose of CBD during the inflammatory period was associated with enhanced anxiety in adult life. PERSPECTIVE: The treatment of nociceptive stimuli with CBD and opioids during the first week of life demonstrated significant sex differences in adult life on anxiety behavior and supraspinal pain sensitivity.

Cannabis Roots: Therapeutic, Biotechnological and Environmental Aspects

Since the legalization of recreational cannabis in Canada in 2018, the number of licenses for this crop has increased significantly, resulting in an increase in waste generated. Nevertheless, cannabis roots were once used for their therapeutic properties, indicating that they could be valued today rather than dismissed. This review will focus on both traditional therapeutic aspects and potential use of roots in modern medicine while detailing the main studies on active phytomolecules found in cannabis roots. The environmental impact of cannabis cultivation and current knowledge of the root-associated microbiome are also presented as well as their potential applications in biotechnology and phytoremediation. Thus, several high added-value applications of cannabis roots resulting from scientific advances in recent years can be considered to remove them from discarded residues.

An Overview of Cannabidiol as a Multifunctional Drug: Pharmacokinetics and Cellular Effects

Cannabidiol (CBD), a non-psychoactive compound derived from Cannabis Sativa, has garnered increasing attention for its diverse therapeutic potential. This comprehensive review delves into the complex pharmacokinetics of CBD, including factors such as bioavailability, distribution, safety profile, and dosage recommendations, which contribute to the compound's pharmacological profile. CBD's role as a pharmacological inhibitor is explored, encompassing interactions with the endocannabinoid system and ion channels. The compound's anti-inflammatory effects, influencing the Interferon-beta and NF-κB, position it as a versatile candidate for immune system regulation and interventions in inflammatory processes. The historical context of Cannabis Sativa's use for recreational and medicinal purposes adds depth to the discussion, emphasizing CBD's emergence as a pivotal phytocannabinoid. As research continues, CBD's integration into clinical practice holds promise for revolutionizing treatment approaches and enhancing patient outcomes. The evolution in CBD research encourages ongoing exploration, offering the prospect of unlocking new therapeutic utility.

Alzheimer's disease, aging, and cannabidiol treatment: a promising path to promote brain health and delay aging

Alzheimer's disease (AD) is the most common neurodegenerative disease characterized by progressive memory loss, neurodegeneration, and cognitive decline. Aging is one of the risk factors for AD. Although the mechanisms underlying aging and the incidence rate of AD are unclear, aging and AD share some hallmarks, such as oxidative stress and chronic inflammation. Cannabidiol (CBD), the major non-psychoactive phytocannabinoid extracted from Cannabis sativa, has recently emerged as a potential candidate for delaying aging and a valuable therapeutic tool for the treatment of aging-related neurodegenerative diseases due to its antioxidant and anti-inflammation properties. This article reviews the relevant literature on AD, CBD treatment for AD, cellular senescence, aging, and CBD treatment for aging in recent years. By analyzing these published data, we attempt to explore the complex correlation between cellular senescence, aging, and Alzheimer's disease, clarify the positive feedback effect between the senescence of neurocytes and Alzheimer's disease, and summarize the role and possible molecular mechanisms of CBD in preventing aging and treating AD. These data may provide new ideas on how to effectively prevent and delay aging, and develop effective treatment strategies for age-related diseases such as Alzheimer's disease.

Cannabidiol and brain function: current knowledge and future perspectives

Cannabidiol (CBD) is a naturally occurring non-psychoactive cannabinoid found in Cannabis sativa, commonly known as cannabis or hemp. Although currently available CBD products do not meet the safety standards of most food safety authorities to be approved as a dietary supplement or food additive, CBD has been gaining widespread attention in recent years due to its various potential health benefits. While primarily known for its therapeutic effects in managing epileptic seizures, psychosis, anxiety, (neuropathic) pain, and inflammation, CBD's influence on brain function has also piqued the interest of researchers and individuals seeking to enhance cognitive performance. The primary objective of this review is to gather, synthesize, and consolidate scientifically proven evidence on the impact of CBD on brain function and its therapeutic significance in treating neurological and mental disorders. First, basic background information on CBD, including its biomolecular properties and mechanisms of action is presented. Next, evidence for CBD effects in the human brain is provided followed by a discussion on the potential implications of CBD as a neurotherapeutic agent. The potential effectiveness of CBD in reducing chronic pain is considered but also in reducing the symptoms of various brain disorders such as epilepsy, Alzheimer's, Huntington's and Parkinson's disease. Additionally, the implications of using CBD to manage psychiatric conditions such as psychosis, anxiety and fear, depression, and substance use disorders are explored. An overview of the beneficial effects of CBD on aspects of human behavior, such as sleep, motor control, cognition and memory, is then provided. As CBD products remain largely unregulated, it is crucial to address the ethical concerns associated with their use, including product quality, consistency, and safety. Therefore, this review discusses the need for responsible research and regulation of CBD to ensure its safety and efficacy as a therapeutic agent for brain disorders or to stimulate behavioral and cognitive abilities of healthy individuals.

Cannabidiol improves memory and decreases IL-1β serum levels in rats with lipopolysaccharide-induced inflammation

AIM

Memory improving and anti-inflammatory properties of cannabidiol (CBD) were investigated in an experimental model of lipopolysaccharide (LPS)-induced inflammation.

Cannabidiol acts as molecular switch in innate immune cells to promote the biosynthesis of inflammation-resolving lipid mediators

Cannabinoids are phytochemicals from cannabis with anti-inflammatory actions in immune cells. Lipid mediators (LM), produced from polyunsaturated fatty acids (PUFA), are potent regulators of the immune response and impact all stages of inflammation. How cannabinoids influence LM biosynthetic networks is unknown. Here, we reveal cannabidiol (CBD) as a potent LM class-switching agent that stimulates the production of specialized pro-resolving mediators (SPMs) but suppresses pro-inflammatory eicosanoid biosynthesis. Detailed metabololipidomics analysis in human monocyte-derived macrophages showed that CBD (i) upregulates exotoxin-stimulated generation of SPMs, (ii) suppresses 5-lipoxygenase (LOX)-mediated leukotriene production, and (iii) strongly induces SPM and 12/15-LOX product formation in resting cells by stimulation of phospholipase A2-dependent PUFA release and through Ca2+-independent, allosteric 15-LOX-1 activation. Finally, in zymosan-induced murine peritonitis, CBD increased SPM and 12/15-LOX products and suppressed pro-inflammatory eicosanoid levels in vivo. Switching eicosanoid to SPM production is a plausible mode of action of CBD and a promising inflammation-resolving strategy.

Sila-CBD Derivatives as Inhibitors of Heme-Induced NLRP3 Inflammasome: Application in Hemolytic Diseases

Synthesis and biological evaluation of silicon-incorporated phytocannabinoids with improved pharmacological properties toward inflammatory diseases are described. The synthesized sila-analogues 15a, 15b, and 15c displayed potent inhibition of pro-inflammatory cytokines, including IL-1β, TNF-α, and IL-6 at 10 μM. Further, the release of heme during the lysis of red blood cells in hemolytic diseases is one of the major reasons for inflammation associated with the pathophysiology of these diseases. Due to scanty literature related to inhibitors of heme-mediated induction of the NLRP3 inflammasome, we decided to test these compounds against it. Compounds 15a and 15c significantly inhibited the heme-mediated induction of the NLRP3 inflammasome at a concentration of 0.1 μM. Interestingly, the sila-CBD derivatives also showed higher metabolic stability in contrast to their carbon analogues. Anti-NLRP3 inflammasome activity of compounds 15a and 15c were further validated in vivo against heme-mediated peritoneal inflammation. The anti-inflammatory activity of these compounds could be useful in treating diseases such as sickle cell anemia and thalassemia involving the hemolysis-mediated activation of the NLRP3 inflammasome.

Visible-Light Photoswitchable Benzimidazole Azo-Arenes as β-Arrestin2-Biased Selective Cannabinoid 2 Receptor Agonists

The cannabinoid 2 receptor (CB2 R) has high therapeutic potential for multiple pathogenic processes, such as neuroinflammation. Pathway-selective ligands are needed to overcome the lack of clinical success and to elucidate correlations between pathways and their respective therapeutic effects. Herein, we report the design and synthesis of a photoswitchable scaffold based on the privileged structure of benzimidazole and its application as a functionally selective CB2 R "efficacy-switch". Benzimidazole azo-arenes offer huge potential for the broad extension of photopharmacology to a wide range of optically addressable biological targets. We used this scaffold to develop compound 10 d, a "trans-on" agonist, which serves as a molecular probe to study the β-arrestin2 (βarr2) pathway at CB2 R. βΑrr2 bias was observed in CB2 R internalization and βarr2 recruitment, while no activation occurred when looking at Gα16 or mini-Gαi . Overall, compound 10 d is the first light-dependent functionally selective agonist to investigate the complex mechanisms of CB2 R-βarr2 dependent endocytosis.

Parkinson's disease, epilepsy, and amyotrophic lateral sclerosis-emerging role of AMPA and kainate subtypes of ionotropic glutamate receptors

Ionotropic glutamate receptors (iGluRs) mediate the majority of excitatory neurotransmission and are implicated in various neurological disorders. In this review, we discuss the role of the two fastest iGluRs subtypes, namely, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate receptors, in the pathogenesis and treatment of Parkinson's disease, epilepsy, and amyotrophic lateral sclerosis. Although both AMPA and kainate receptors represent promising therapeutic targets for the treatment of these diseases, many of their antagonists show adverse side effects. Further studies of factors affecting the selective subunit expression and trafficking of AMPA and kainate receptors, and a reasonable approach to their regulation by the recently identified novel compounds remain promising directions for pharmacological research.

Cannabinoids in Medicine: A Multifaceted Exploration of Types, Therapeutic Applications, and Emerging Opportunities in Neurodegenerative Diseases and Cancer Therapy

In this review article, we embark on a thorough exploration of cannabinoids, compounds that have garnered considerable attention for their potential therapeutic applications. Initially, this article delves into the fundamental background of cannabinoids, emphasizing the role of endogenous cannabinoids in the human body and outlining their significance in studying neurodegenerative diseases and cancer. Building on this foundation, this article categorizes cannabinoids into three main types: phytocannabinoids (plant-derived cannabinoids), endocannabinoids (naturally occurring in the body), and synthetic cannabinoids (laboratory-produced cannabinoids). The intricate mechanisms through which these compounds interact with cannabinoid receptors and signaling pathways are elucidated. A comprehensive overview of cannabinoid pharmacology follows, highlighting their absorption, distribution, metabolism, and excretion, as well as their pharmacokinetic and pharmacodynamic properties. Special emphasis is placed on the role of cannabinoids in neurodegenerative diseases, showcasing their potential benefits in conditions such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. The potential antitumor properties of cannabinoids are also investigated, exploring their potential therapeutic applications in cancer treatment and the mechanisms underlying their anticancer effects. Clinical aspects are thoroughly discussed, from the viability of cannabinoids as therapeutic agents to current clinical trials, safety considerations, and the adverse effects observed. This review culminates in a discussion of promising future research avenues and the broader implications for cannabinoid-based therapies, concluding with a reflection on the immense potential of cannabinoids in modern medicine.

Phenomic Microglia Diversity as a Druggable Target in the Hippocampus in Neurodegenerative Diseases

Phenomics, the complexity of microglia phenotypes and their related functions compels the continuous study of microglia in disease animal models to find druggable targets for neurodegenerative disorders. Activation of microglia was long considered detrimental for neuron survival, but more recently it has become apparent that the real scenario of microglia morphofunctional diversity is far more complex. In this review, we discuss the recent literature on the alterations in microglia phenomics in the hippocampus of animal models of normal brain aging, acute neuroinflammation, ischemia, and neurodegenerative disorders, such as AD. Microglia undergo phenomic changes consisting of transcriptional, functional, and morphological changes that transform them into cells with different properties and functions. The classical subdivision of microglia into M1 and M2, two different, all-or-nothing states is too simplistic, and does not correspond to the variety of phenotypes recently discovered in the brain. We will discuss the phenomic modifications of microglia focusing not only on the differences in microglia reactivity in the diverse models of neurodegenerative disorders, but also among different areas of the brain. For instance, in contiguous and highly interconnected regions of the rat hippocampus, microglia show a differential, finely regulated, and region-specific reactivity, demonstrating that microglia responses are not uniform, but vary significantly from area to area in response to insults. It is of great interest to verify whether the differences in microglia reactivity may explain the differential susceptibility of different brain areas to insults, and particularly the higher sensitivity of CA1 pyramidal neurons to inflammatory stimuli. Understanding the spatiotemporal heterogeneity of microglia phenomics in health and disease is of paramount importance to find new druggable targets for the development of novel microglia-targeted therapies in different CNS disorders. This will allow interventions in three different ways: (i) by suppressing the pro-inflammatory properties of microglia to limit the deleterious effect of their activation; (ii) by modulating microglia phenotypic change to favor anti-inflammatory properties; (iii) by influencing microglia priming early in the disease process.

Under the umbrella of depression and Alzheimer's disease physiopathology: Can cannabinoids be a dual-pleiotropic therapy?

Depression and Alzheimer´s disease (AD) are two disorders highly prevalent worldwide. Depression affects more than 300 million people worldwide while AD affects 60-80% of the 55 million cases of dementia. Both diseases are affected by aging with high prevalence in elderly and share not only the main brain affected areas but also several physiopathological mechanisms. Depression disease is already ascribed as a risk factor to the development of AD. Despite the wide diversity of pharmacological treatments currently available in clinical practice for depression management, they remain associated to a slow recovery process and to treatment-resistant depression. On the other hand, AD treatment is essentially based in symptomatology relieve. Thus, the need for new multi-target treatments arises. Herein, we discuss the current state-of-art regarding the contribution of the endocannabinoid system (ECS) in synaptic transmission processes, synapses plasticity and neurogenesis and consequently the use of exogenous cannabinoids in the treatment of depression and on delaying the progression of AD. Besides the well-known imbalance of neurotransmitter levels, including serotonin, noradrenaline, dopamine and glutamate, recent scientific evidence highlights aberrant spine density, neuroinflammation, dysregulation of neurotrophic factor levels and formation of amyloid beta (Aβ) peptides, as the main physiopathological mechanisms compromised in depression and AD. The contribution of the ECS in these mechanisms is herein specified as well as the pleiotropic effects of phytocannabinoids. At the end, it became evident that Cannabinol, Cannabidiol, Cannabigerol, Cannabidivarin and Cannabichromene may act in novel therapeutic targets, presenting high potential in the pharmacotherapy of both diseases.