Molecular Mechanisms Underlying Neuroinflammation Intervention with Medicinal Plants: A Critical and Narrative Review of the Current Literature

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“Neuroinflammation is a key factor in the progression of neurodegenerative diseases, driven by the dysregulation of molecular pathways and activation of the brain’s immune system, resulting in the release of pro-inflammatory and oxidative molecules. This chronic inflammation is exacerbated by peripheral leukocyte infiltration into the central nervous system.

Medicinal plants, with their historical use in traditional medicine, have emerged as promising candidates to mitigate neuroinflammation and offer a sustainable alternative for addressing neurodegenerative conditions in a green healthcare framework.

This review evaluates the effects of medicinal plants on neuroinflammation, emphasizing their mechanisms of action, effective dosages, and clinical implications, based on a systematic search of databases such as PubMed, SCOPUS, and Web of Science.

The key findings highlight that plants like Cleistocalyx nervosum var. paniala, Curcuma longa

Cannabis sativa,

and Dioscorea nipponica reduce pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β), inhibit enzymes (COX-2 and iNOS), and activate antioxidant pathways, particularly Nrf2. NF-κB emerged as the primary pro-inflammatory pathway inhibited across studies. While the anti-inflammatory potential of these plants is significant, the variability in dosages and phytochemical compositions limits clinical translation.

Here, we highlight that medicinal plants are effective modulators of neuroinflammation, underscoring their therapeutic potential. Future research should focus on animal models, standardized protocols, and safety assessments, integrating advanced methodologies, such as genetic studies and nanotechnology, to enhance their applicability in neurodegenerative disease management.”

https://pubmed.ncbi.nlm.nih.gov/39861194/

“Addressing neuroinflammation to reduce disease severity and improve patient outcomes is a promising strategy against neurodegeneration. From a molecular perspective, there are several conventional drug targets for neuroinflammation, such as enzymes, receptors, and ion channels. However, the high cost of synthetic drugs presents a challenge, emphasizing the need for alternative approaches. This has heightened interest in naturally occurring medicinal plants known for their antioxidant, anti-inflammatory, and neuroprotective properties. These plants are often more cost-effective and have been safely utilized in treatments for thousands of year.”

https://www.mdpi.com/1424-8247/18/1/133

Optimization and Evaluation of Cannabis-Based Magistral Formulations: A Path to Personalized Therapy

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“Introduction: The official implementation of pharmaceutical-grade cannabis raw materials for medicinal use has permitted doctors to prescribe and pharmacists to prepare cannabis-based formulations. The objective of the pharmaceutical development and manufacturing process optimization work was to propose a suppository formulation containing doses of 25 mg and 50 mg of tetra-hydrocannabinol (∆-9-THC) as an alternative to existing inhalable or orally administered formulations. The formulation could be used for rectal or vaginal administration, thereby providing dosage control in the treatment of endometriosis and other conditions involving pain. In this study, two substrates from suppositories with standardized Cannabis extractum normatum (CEX) were used: cocoa butter and Witepsol® H15.

Materials and methods: The long-term stability of CEX was investigated over a period of up to 24 months. The concentrations of ∆-9-THC, cannabidiol (CBD), and cannabinol (CBN) were determined using an HPLC method. Furthermore, the water content of the extract, the ethanol residue, and the microbiological purity were determined. The pharmaceutical properties of CEX-incorporated suppositories, namely content uniformity, hardness, softening time, total deformation time, disintegration time, and the release profile of ∆-9-THC, CBD, and CBN, were evaluated in order to develop optimal preparation procedures for pharmacists.

Results and discussion: Following a 24-month stability study on CEX, no significant alterations in component content were observed beyond the specified requirements. The disintegration time, total deformation time, and hardness of the suppositories based on Witepsol® H15 with CEX were found to be longer and higher, respectively, than those of suppositories formulated with cocoa butter. In vitro studies demonstrated that suppositories prepared with Witepsol® H15 exhibited superior release of ∆-9-THC compared to those prepared with cocoa butter.

Conclusions: We suggest that pharmacists making prescription drugs in a pharmacy setting in the form of medical marijuana suppositories will receive a better release profile of the drug by choosing Witepsol® H15 as a substrate.”

https://pubmed.ncbi.nlm.nih.gov/39861136/

https://www.mdpi.com/1424-8247/18/1/73

Exploring the Therapeutic Potential of Cannabidiol in U87MG Cells: Effects on Autophagy and NRF2 Pathway

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“Cannabinoids include both endogenous endocannabinoids and exogenous phytocannabinoids, such as cannabidiol (CBD), and have potential as therapeutic agents in cancer treatment due to their selective anticancer activities.

CBD exhibits both antioxidant and pro-oxidant effects depending on its concentration and cell types. These properties allow CBD to influence oxidative stress responses and potentially enhance the efficacy of antitumor therapies.

In this study, we treated U87MG glioma cells with low dose (1 μM) CBD and evaluated its molecular effects.

Our findings indicate that CBD reduced cell viability by 20% (p < 0.05) through the alteration of mitochondrial membrane potential. The alteration of redox status by CBD caused an attempt to rescue mitochondrial functionality through nuclear localization of the GABP transcription factor involved in mitochondria biogenesis. Moreover, CBD treatment caused an increase in autophagic flux, as supported by the increase in Beclin-1 and the ratio of LC3-II/LC3-I. Due to mitochondria functionality alteration, pro-apoptotic proteins were induced without activating apoptotic effectors Caspase-3 or Caspase-7. The study of the transcription factor NRF2 and the ubiquitin-binding protein p62 expression revealed an increase in their levels in CBD-treated cells.

In conclusion, low-dose CBD makes U87MG cells more vulnerable to cytotoxic effects, reducing cell viability and mitochondrial dynamics while increasing autophagic flux and redox systems. This explains the mechanisms by which glioma cells respond to CBD treatment.

These findings highlight the therapeutic potential of CBD, suggesting that modulating NRF2 and autophagy pathways could represent a promising strategy for glioblastoma treatment.”

https://pubmed.ncbi.nlm.nih.gov/39857352/

“Our study demonstrates that low-dose CBD treatment (1 μM) in U87MG glioblastoma cells stimulates the autophagy process, which is essential for mitochondrial renewal, contributing to an increase in mitochondria with altered membrane potential. Moreover, CBD-treated U87MG cells present an abnormal activation of the NRF2 pathway, reducing the expression of antioxidant target genes and consequently altering mitochondrial integrity. These molecular effects suggest that CBD could have therapeutic repercussions or be useful in the development of multi-target agents acting on the NRF2 mitochondrial biogenesis–autophagy axis.”

https://www.mdpi.com/2076-3921/14/1/18

Anti-Inflammatory Effects of Cannabigerol In Vitro and In Vivo Are Mediated Through the JAK/STAT/NFκB Signaling Pathway

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“Cannabinoid compounds have potential as treatments for a variety of conditions, with cannabigerol (CBG) being known for its anti-inflammatory properties.

In this study, we investigated the effects of CBG in a cellular model of 1-chloro-2,4-dinitrobenzene (DNCB)-induced atopic dermatitis (AD).

In the cellular model, we confirmed the cytotoxicity of CBG and downregulated the expression of inflammatory markers CCL26IL1BIL6, and TNF (p < 0.001). In the mouse model, clinical, histological, and immunological changes were analyzed.

The results showed that CBG improved dermatitis severity score, epidermal thickness, and mast cell count and reduced inflammatory cytokines (TslpIl1bIl4Il6Il13Il17Il18Il22, and Il33) by qRT-PCR (p < 0.001). Western blot results showed modulated changes in JAK1, JAK2, TYK2, STAT1, STAT2, STAT3, p-STAT3, STAT6, and p-STAT6 (p < 0.05). Subsequently, p-IκBα, NF-κB, and p-NF-κB signaling factors were also reduced (p < 0.05), with corresponding changes in skin barrier factors.

The results of this study indicate that CBG effectively alleviates AD-like symptoms and suggest the potential of CBG as a therapeutic agent.”

https://pubmed.ncbi.nlm.nih.gov/39851511/

https://www.mdpi.com/2073-4409/14/2/83

Cannabidiol Modulates Neuroinflammatory and Estrogen-Related Pathways in a Sex-Specific Manner in a Chronic Stress Model of Depression

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“Evidence indicates a bidirectional link between depressive symptoms and neuroinflammation. This study evaluated chronic cannabidiol (CBD) treatment effects in male and female rats subjected to the unpredictable chronic mild stress (UCMS) model of depression.

We analyzed the gene expression related to neuroinflammation, cannabinoid signaling, estrogen receptors, and specific microRNAs in the ventromedial prefrontal cortex (vmPFC), CA1, and ventral subiculum (VS). UCMS influenced immobility in a sex-specific manner, increasing it in males and decreasing it in females, effects that were reversed by CBD.

CBD also normalized the UCMS-induced upregulation of tumor necrosis factor α (TNF-α) in the CA1 and VS in males. In both sexes, UCMS induced the upregulation of the nuclear factor kappa B subunit 1 (NF-κB1) gene in the VS, which was unaffected by CBD. Additionally, CBD reversed CB1 downregulation in the VS of males but not in the vmPFC of either sex. In males, CBD restored the UCMS-induced downregulation of VS estrogen receptor genes ERα and ERβ. UCMS also altered miR-146a-5p expression, downregulating it in females (VS) and upregulating it in males (CA1), with no CBD effect.

These findings highlight the sex-specific mechanisms of CBD’s antidepressant effect, with hippocampal neuroinflammatory and estrogenic pathways playing a key role in males.”

https://pubmed.ncbi.nlm.nih.gov/39851527/

“Cannabidiol (CBD), renowned for its anti-inflammatory and antioxidative properties, has emerged as a promising candidate for treating depression.”

https://www.mdpi.com/2073-4409/14/2/99

Unveiling Cannabinoids and Terpenes Diversity in Cannabis sativa L. from Northern India for Future Breeding Strategies

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“Cannabis sativa L. is an important medicinal plant with high commercial value.

In recent years, the research interest in cannabidiol (CBD) and terpene-rich cannabis has been rapidly expanding due to their high therapeutic potential.

The present study aims to explore the phytocannabinoids and terpenes diversity in Cannabis sativa collected from different parts of northern India.

Our findings revealed that the cannabinoids and terpenes synthesize together in capitate stalked and capitate sessile glandular trichomes, whereas bulbous glands synthesize only terpenes. The North Indian C. sativa is mainly dominated by tetrahydrocannabinol (THC). The CBD-rich plant diversity is nominal (1.11%) in studied north Indian C. sativa. The essential oil profiling reveals (E)-caryophyllene (10.30-36.80%) as the major constituent, followed by α-humulene (0.50-15.29%) and α-bisabolol (0.00-16.40%) in the North Indian population.

The cannabinoids and terpenes content showed significant diversity among and within the five studied populations. The correlation analysis between cannabinoids and terpenes indicates that α-pinene, β-pinene, and limonene positively correlated with CBD content. Similarly, α- and β-selinene correlate positively with tetrahydrocannabinolic acid (THCA) content. This study could help to identify the key cultivars from India and establish a consistent chemotype for future breeding programs.”

https://pubmed.ncbi.nlm.nih.gov/39853702/

https://onlinelibrary.wiley.com/doi/10.1002/cbdv.202402278

Cannabidiol suppresses proliferation and induces cell death, autophagy and senescence in human cholangiocarcinoma cells via the PI3K/AKT/mTOR pathway

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“Background and aim: Cholangiocarcinoma (CCA) is usually diagnosed at a late stage, leading to treatment failure. Cannabidiol (CBD), exhibits diverse anti-cancer effects in various cancers, offering avenues for improving CCA treatment. This study investigated the effects of CBD on human CCA cells and the underlying mechanisms in vitro and in vivo.

Experimental procedure: The effects of CBD on three CCA cell lines (KKU-213B, KKU-100, KKU-055) were assessed using the SRB assay, clonogenic assay, cell cycle arrest, and 3D holotomography. Morphological changes were examined using transmission electron microscopy, while mitochondrial ROS levels and mitochondrial membrane potential were studied using MitoSOX, JC-1, and DCFH-DA. Cellular senescence induction was evaluated via SA-β-gal staining. Protein associatedwith autophagy and cellular senescence were analyzed using Western blot and/or immunofluorescent assays. A xenograft model demonstrated the anti-tumor activity of CBD and the induction of cellular senescence through immunohistochemistry targeting PCNA, β-gal, and p21.

Results and conclusion: CBD effectively inhibited CCA cell proliferation, suppressed colony formation and induced G0/G1 phase cell cycle arrest. Morphological examination revealed lipid droplets/vesicles in CCA cell lines. CBD induced autophagy by upregulating LC3BII, downregulating p62, and inhibiting the p-PI3K, p-AKT, and p-mTOR pathways. Additionally, CBD disrupted mitochondrial homeostasis by elevating ROS, reducing membrane potential, and induced cellular senescence by increasing the expression of p53 and p21. In-vitro results were confirmed by xenograft models. Overall, CBD suppresses proliferation and induces cell death, autophagy and senescence in CCA cells via the PI3K/AKT/mTOR pathway, which indicates a therapeutic option for CCA treatment.”

https://pubmed.ncbi.nlm.nih.gov/39850601/

“Although CBD has shown anti-tumor activity in various solid tumors, including CCA, its mechanism of action remains poorly understood.”

“The study reported here has shown that CBD has a significant anti-tumor effect on CCA cells through various mechanisms, including the inhibition of cell proliferation both in vitro and in vivo, the reduction of colony formation ability and the induction of multiple cellular processes, notably autophagy, cell cycle arrest, cellular senescence, mitochondrial dysfunction, lipid droplet formation, and ROS overproduction.

The significant findings from our study strongly suggest that CBD, through its targeting of the PI3K/AKT/mTOR pathway, holds great promise as a therapeutic agent for treating CCA and potentially other cancers.”

“Various herbal agents, including CBD, have shown promise for the treatment of CCA.”

https://www.sciencedirect.com/science/article/pii/S2225411024000506?via%3Dihub

Oral cannabidiol did not impair learning and memory in healthy adults

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“Background: The effect of oral Cannabidiol (CBD) on interference during learning and memory (L&M) in healthy human volunteers has not been studied.

Method: A two-arm crossover, randomized, double-blind, placebo-controlled trial was conducted at Colorado State University Pueblo (CSU Pueblo) to evaluate the effects of 246 mg oral CBD on L&M in healthy adults. Among 57 healthy volunteers enrolled, 35 were included in the analyses. For assessment of L&M, Montreal Cognitive Assessment (MOCA) was used to evaluate verbal baseline cognitive function; RAVLT-R tests (List A and List B recalls, Proactive and Retroactive Interference ratios, and Forgetting Speed ratio) were used to evaluate verbal declarative memory; and total prose recall was used to evaluate verbal logical memory. Linear Mixed Models with Bonferroni Corrections were used to compare L&M results between primary outcomes (CBD vs. placebo) and secondary demographic outcomes, with a two-tailed statistical significance of P < 0.05.

Results: CBD administration did not affect any of the dependent variables measured compared to the placebo group. There were no effects of THC, history of CBD use, or sex on CBD’s modulation of L&M. However, a highly significant interaction effect between treatment groups (CBD vs. placebo) and age of subjects was observed for the PI ratio (P = 0.008; n = 35).

Conclusions: The results of this study suggest that administration of oral CBD alone does not significantly impair L&M in healthy adults. However, age might influence CBD related modulation of proactive interference during human L&M. Future research involving a larger group of older adults is needed to confirm this potential effect.”

https://pubmed.ncbi.nlm.nih.gov/39849639/

https://jcannabisresearch.biomedcentral.com/articles/10.1186/s42238-025-00262-2

Cannabis oil in treating Parkinson’s disease: improvement of motor and non-motor symptoms: a case report

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“Parkinson’s disease (PD) is characterized by progressive loss of dopaminergic neurons in the substantia nigra pars compacta, which leads to a reduction in the production of dopamine. Medication with levodopa becomes less effective as the disease progresses. Despite the excellent results observed in clinical practice with the medicinal use of Cannabis in the treatment of PD, the level of scientific evidence is still limited due to the small number of studies published in this field.

We present the case of a 77-year-old man diagnosed 22 years ago with PD in an advanced stage, with significant bradykinesia, tremor, and rigidity along with the inability to maintain an upright position and walk, exacerbated by a femur fracture. He also had advanced dysphagia, resulting in a gastrostomy. Although lucid, he showed no interest in conversation and tended to become depressed and isolated. He used Prolopa® with no satisfactory therapeutic response.

After starting treatment with Cannabis sativa oil, he is now able to walk around the house frequently and eat pasty food regularly without choking or broncho-aspiration episodes. There has also been a significant improvement in non-motor symptoms; he is more active, cheerful, communicative, and attentive to his surroundings.

Further studies are needed to elucidate these results and the mechanisms of action of cannabinoids through which they exert possible neuroprotective and neuroreparative effects.

These compelling results suggest that cannabis oil may offer a valuable and effective therapeutic option for individuals with Parkinson’s disease.”

https://pubmed.ncbi.nlm.nih.gov/39841751/

“Considering Parkinson’s disease a neurodegenerative process, in this report we present a unique case where, in addition to slowing the progression of the disease, there was recovery of motor and cognitive functions in a patient with advanced stage Parkinson’s disease, after starting treatment with full-spectrum cannabis oil.”

https://www.scielo.br/j/bjb/a/nqQFzz3NtnydWM8KWdfYyWz/?lang=en

The proof is in the pudding: patient engagement in studying cannabidiol in mild cognitive impairment

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“Background: Patient engagement (PE) in clinical trials has gained importance yet remains uncommon, particularly in patients with mild cognitive impairment (MCI), a critical precursor to Alzheimer’s disease (AD). Cannabidiol (CBD) shows potential in slowing MCI progression due to its neuroprotective and anti-inflammatory properties. In CBD research, PE is underutilized too. To design a study on CBD for MCI, we administered an online survey to individuals with MCI to better understand their preferences for trial setup and outcomes.

Methods: We asked 209 individuals with MCI to complete an online survey assessing (i) willingness to participate in a trial using CBD; (ii) importance of improvements in various domains; (iii) acceptance of adverse events (AEs); (iv) reasons for AE-related dropout; (v) willingness to undergo blood sampling and lumbar puncture to assess AD pathology; and (vi) willingness to participate in a trial with a 50% chance of receiving a placebo. Data were analyzed with descriptive statistics.

Results: N = 118 agreed to participate and N = 88 completed the survey. Participants prioritized improvement in cognitive abilities (87.5%), followed by quality of life (63.6%), daily activities (55.7%), sleep (55.7%), pain (52.3%), mood (52.3%), behavior (48.9%), and anxiety (43.2%). Headache (55.7%) was the least accepted AE followed by nausea (46.6%), fatigue (35.2%), and diarrhea (35.2%). Persistent diarrhea (90.9%) and severe fatigue (84.1%) were the main reasons for potential dropout. While most would undergo blood sampling (67.0%), only a minority (21.6%) would accept lumbar puncture. One-third were ready to participate (34.1%), while 54.5% were interested pending details. Among those in favor of participation, 71.6% would participate even with a 50% chance of placebo.

Conclusions: Our study identified cognitive improvement as highly relevant for patients, indicating cognitive assessment tools as primary endpoints in MCI research. Given concerns about AEs, dose titration should be carefully considered to enhance acceptance and prevent AEs. Blood sampling seems well-accepted for AD biomarker assessment. Despite potential AEs, participation in a trial using CBD for MCI is seen as attractive, even under placebo-controlled conditions. This cross-sectional study emphasizes the importance of patient engagement in designing high-quality trials for using CBD to treat MCI.”

https://pubmed.ncbi.nlm.nih.gov/39844123/

“In summary, this study is the first to incorporate PE into a trial on the use of CBD for MCI, as there are currently no existing PE activities in this area. It provides valuable insights into the concerns, aims, and needs of people with MCI and offers initial implications for planning and conducting future studies involving this population. Our main message is to encourage the incorporation of PE activities in the drug research process, not only to reflect the goals and needs of patients but also to improve the quality of research.”

https://bmccomplementmedtherapies.biomedcentral.com/articles/10.1186/s12906-025-04753-w