“Background and purpose: Chronic neuropathic pain (NP) is commonly associated with cognitive and emotional impairments. Cannabidiol (CBD) presents a broad spectrum of action with a potential analgesic effect. This work investigates the CBD effect on comorbidity between chronic NP, depression, and memory impairment.
Experimental approach: The connection between the neocortex and the hippocampus was investigated with biotinylated dextran amine (BDA) deposits in the prelimbic cortex (PrL). Wistar rats were submitted to chronic constriction injury (CCI) of the sciatic nerve and CA1 treatment with CBD (15, 30, 60 nmol).
Key results: BDA-labeled were found in CA1 and dentate gyrus. CCI-induced mechanical and cold allodynia increased c-Fos protein expression in the PrL and CA1. The number of astrocytes in PrL and CA1 increased, and the number of neuroblasts decreased in CA1. The CCI animals showed increasing depressive-like behaviors, such as memory impairment. CBD (60 nmol) treatment decreased mechanical and cold allodynia, attenuated depressive-associated behaviors, and improved memory performance. Cobalt chloride (CoCl2: 1 nM), WAY-100635 (0.37 nmol), and AM251 (100 nmol) intra-PrL reversed the CBD (60 nmol) effect intra-CA1, both in nociceptive, cognitive, and depressive behaviors.
Conclusion: CBD represents a promising therapeutic perspective in the pharmacological treatment of chronic NP and associated comorbidities such as depression and memory impairments. The CBD effects possibly recruit the CA1-PrL pathway, inducing neuroplasticity. CBD acute treatment into the CA1 produces functional and molecular morphological improvements.”
“Cannabis sativa L. (hemp) is a herbaceous plant rich in cannabinoids with a long history of use in pain treatment.
The most well-characterized cannabinoids, cannabidiol (CBD) and Δ9-tetrahydrocannabinol (Δ9-THC), garnered much attention in chemotherapy-induced peripheral neuropathy (CIPN) treatment. However, few studies have investigated the biological benefits and mechanism of hemp extract on CIPN.
In the present study, hemp extract (JG) rich in cannabinoids was extracted by supercritical fluid carbon dioxide extraction (SFCE). The antinociceptive efficacy was evaluated using a paclitaxel-induced peripheral neuropathy (PIPN) rat model based on behavioral tests. Further omics-based approaches were applied to explore the potential mechanisms.
The results showed that JG decreased mechanical allodynia, thermal hyperalgesia, and inflammatory cytokines in PIPN rats significantly. Transcriptome analysis identified seven key genes significantly regulated by JG in PIPN model rats, mainly related to the neuroactive ligand-receptor interaction pathway, PPAR signaling pathway, and cAMP signaling pathway. In metabolomic analysis, a total of 39 significantly altered metabolites were identified, mainly correlated with pentose and glucuronate interconversions and the glycerophospholipid metabolism pathway.
Gut microbiota analysis suggested that increased community Lachnoclostridium and Lachnospiraceae_UCG-006 in PIPN rats can be reversed significantly by JG.
In conclusion, hemp extract exhibited antinociceptive effects on PIPN. The analgesic mechanism was probably related to the regulation of inflammation, neuroactive ligand-receptor interaction pathway, sphingolipid metabolism, etc. This study provides novel insights into the functional interactions of Cannabis sativa L. extract on PIPN.”
“In conclusion, the antinociceptive effects and mechanism of Cannabis sativa L. extract rich in cannabinoids in PIPN rats were evaluated by using pharmacological methods integrated with transcriptomic analysis, metabolomic analysis, and gut microbiota analysis.
Cannabis sativa L. extract effectively alleviated neuropathic pain induced by PTX, mainly by the identified 7 key genes, 39 metabolic biomarkers, and 2 bacterial genera.
Related pathways may be involved in the inflammatory response, regulating neuroactive ligand–receptor interaction pathway, PPAR signaling pathway, inflammatory mediator regulation of TRP channels, glycerophospholipid metabolism, pentose and glucuronate interconversions, etc.
Our study provides novel insights into the functional interactions of Cannabis sativa L. extract on PIPN, which offers key information for new strategies in PIPN treatment and provides a reference for the medicinal development of hemp.”
“Terpenes are small hydrocarbon compounds that impart aroma and taste to many plants, including Cannabis sativa.
A number of studies have shown that terpenes can produce pain relief in various pain states in both humans and animals. However, these studies were methodologically limited and few established mechanisms of action.
In our previous work, we showed that the terpenes geraniol, linalool, β-pinene, α-humulene, and β-caryophyllene produced cannabimimetic behavioral effects via multiple receptor targets. We thus expanded this work to explore the potential antinociception and mechanism of these Cannabis terpenes in a mouse model of chronic pain.
We first tested for antinociception by injecting terpenes (200 mg/kg, IP) into male and female CD-1 mice with mouse models of chemotherapy-induced peripheral neuropathy (CIPN) or lipopolysaccharide-induced inflammatory pain, finding that the terpenes produced roughly equal antinociception to 10 mg/kg morphine or 3.2 mg/kg WIN55,212. We further found that none of the terpenes produced reward as measured by conditioned place preference, while low doses of terpene (100 mg/kg) combined with morphine (3.2 mg/kg) produced enhanced antinociception vs either alone. We then used the adenosine A2A receptor (A2AR) selective antagonist istradefylline (3.2 mg/kg, IP) and spinal cord-specific CRISPR knockdown of the A2AR to identify this receptor as the mechanism for terpene antinociception in CIPN. In vitro cAMP and binding studies and in silico modeling studies further suggested that the terpenes act as A2AR agonists.
Together these studies identify Cannabis terpenes as potential therapeutics for chronic neuropathic pain and identify a receptor mechanism for this activity.”
“Design: This study is a randomised, placebo-controlled, triple-arm, phase IIA clinical trial with double masking which investigates the effectiveness and safety of Cannabidiol (CBD) as an analgesic for acute dental pain. The intervention drug, Epidiolex is an FDA-approved CBD oral solution (100 mg/ml) derived from the cannabis plant. The psychoactive ingredient tetrahydrocannabinol (THC) is not included. The maximum recommended daily dose of Epidiolex is 20 mg/kg. 64 patients with moderate-severe odontogenic pain participated in the study and REDCap software was utilised to randomly assign participants into groups: CBD10 (10 mg/kg), CBD20 (20 mg/kg) and placebo. A single dose of the respective oral solution was administered, and participants monitored for 3 h. Patients remained blinded to group assignment, as did the outcome assessor. The provider was not blinded. The primary outcome measure was VAS (visual analogue scale) pain difference, compared to baseline and recorded at 7 subsequent marked times following administration (15, 30, 45, 60, 90, 120, 180 min). Additional outcome measures were also recorded: changes in bite force, pain intensity differences, the onset of significant pain relief, the maximum pain relief, psychoactive effects, mood changes and adverse events.
Case selection: 40 female and 21 male patients with moderate-severe odontogenic pain (defined as ≥30 on a 100 mm VAS) with a diagnosis of irreversible pulpitis or pulp necrosis and symptomatic apical periodontitis were included. Participation required a negative test for recent drug and alcohol use, a negative pregnancy test and no use of analgesics within 6 h of the trial. Pregnancy, breastfeeding, hepatic impairment, recreational cannabis users and patients taking CBD metabolising drugs were excluded along with those with an ASA classification above III. Patient characteristics recorded included: age, gender, race, tooth type affected, weight and BMI.
Data analysis: Mixed model analysis was used to compare numerical variables among the cohorts at the marked time intervals. VAS, bite force, Bowdle and Bond/Lader questionnaires were recorded. Inter-group analysis was completed using parametric and non-parametric post-hoc tests, including Holm-Bonferroni adjustment and the Shapiro-Wilk test, to evaluate data normality. NNTs were calculated for both CBD doses- the number of patients needing treatment before one patient experiences a minimum of 50% pain relief. X² tests were used to analyse categorical variables: pain intensity and adverse events. JMP software was used for the statistical analysis.
Results: 64 participants had originally enroled in the study, but three were excluded from data analysis due to ‘unrealistic results’, reporting complete pain relief within the first 15 min. 20 participants were given CBD10, 20 were given CBD20 and 21 placebo. 68% of the participants were Hispanic/Latino whilst 11% were white. The average age was 44 +/- 13.7. There was equal distribution of age, sex, race, tooth type, weight and body mass index (p > 0.05). No subject required rescue pain relief during the 3-h observation period. Compared to baseline VAS, significant pain relief was seen 30 min after drug administration for CBD10, versus after 15 min for CBD20 (p < 0.05). Pain reduction reached 50% at 60 min for CBD10 and at 120 min for CBD20. Both reported maximum pain reduction of 73% of baseline at 180 min. 33% pain reduction from baseline was seen in the placebo group, with a median VAS pain of 67% at 180 min. 45.4% of CBD10 and 46.6% of CBD20 required pain relief after 1-6 h, versus 37.5% of placebo (p > 0.05). Bite force increase was seen in both CBD10 and CBD20 groups at 90 and 180 min, versus no significant differences between time points in the placebo group. On assessing pain intensity, pain reduction was significantly associated with increasing time in the CBD groups (p < 0.001), versus no significant association with the placebo group (p = 0.0521). No statistically significant differences were seen between and within the groups for Bowdle or Bond/Lader questions (p > 0.05). In the 3 h observation period, CBD10 experienced 14 times more sedation symptoms versus placebo (p < 0.05), whilst CBD20 experienced this 8 times more (p < 0.05). Within the 3 h, CBD20 were 10-fold more likely to have diarrhoea and abdominal pain (p < 0.05), with some experiencing pain beyond the 3 h but resolving within the day.
Conclusions: Based on this randomised clinical trial, pure CBD drug Epidiolex demonstrates effective analgesia against acute toothache.”
“Objective: To relate the topical use of cannabis as an analgesic therapeutic alternative in patients with some inflammatory diseases in Salud Social I.P.S during May to July 2023.
Methods: An analytical, retrospective study was carried out. The population from which the sample was obtained corresponds to patients diagnosed with Arthrosis, Unspecified, Non-Toxic Multinodular Goiter, Epilepsy, Unspecified Type Venous Insufficiency (Chronic) (Peripheral), Unspecified Lumbago, Secondary Gonarthrosis, Rotator Cuff Syndrome, Carpal Tunnel Syndrome, in Salud Social I.P.S of Barranquilla, Atlántico. A sample of 23 patients diagnosed with these pathologies was obtained by non-probabilistic convenience sampling.
Results: All patients showed pain relief after two months of follow-up, two experienced adverse effects. Some studies suggest that cannabinoids present in cannabis, such as CBD and THC, may have analgesic and anti-inflammatory properties that could alleviate pain and inflammation associated with these conditions. This is consistent with the present study.
Conclusion: Topical cannabis is presented as a therapeutic alternative in inflammatory diseases, however, it is important to highlight that research on the use of cannabis in these diseases is limited and more studies are needed to fully understand its effects and potential benefits.”
“Introduction: The use of medicinal cannabis for managing pain expands, although its efficacy and safety have not been fully established through randomized controlled trials.
Objectives: This structured, prospective questionnaire-based cohort was aimed to assess long-term effectiveness and safety of cannabis oil extracts in patients with chronic pain.
Methods: Adult Israeli patients licensed to use cannabis oil extracts for chronic pain were followed prospectively for 6 months. The primary outcome measure was change from baseline in average weekly pain intensity, and secondary outcomes were changes in related symptoms and quality of life, recorded before treatment initiation and 1, 3, and 6 months thereafter. Generalized linear mixed model was used to analyze changes over time. In addition, “responders” (≥30% reduction in weekly pain at any time point) were identified.
Results: The study included 218 patients at baseline, and 188, 154, and 131 at 1, 3, and 6 months, respectively. At 6 months, the mean daily doses of cannabidiol and Δ9-tetrahydrocannabinol were 22.4 ± 24.0 mg and 20.8 ± 30.1 mg, respectively. Pain decreased from 7.9 ± 1.7 at baseline to 6.6 ± 2.2 at 6 months (F(3,450) = 26.22, P < 0.0001). Most secondary parameters also significantly improved. Of the 218 participants, 24% were “responders” but could not be identified by baseline parameters. “Responders” exhibited higher improvement in secondary outcomes. Adverse events were common but mostly nonserious.
Conclusion: This prospective cohort demonstrated a modest overall long-term improvement in chronic pain and related symptoms and a reasonable safety profile with the use of relatively low doses of individually titrated Δ9-tetrahydrocannabinol and cannabidiol.”
“In conclusion, this structured, prospective cohort study demonstrated modest improvements in pain, associated symptoms, functioning, and quality of life, and a reduction in opioid use. The reduction in “disease burden” was more pronounced in nearly a quarter of the patients, but no predictors for treatment success could be identified before treatment initiation. The doses of THC and CBD in the oil extracts were modest and considerably lower than those required to achieve similar magnitude of effect by cannabis inflorescence. Although medical cannabis treatment appears to be generally safe for most patients, some still experience SAEs.”
“Cannabis sativa is one of the oldest medicinal plants in human history. Even ancient physicians from hundreds of years ago used Cannabis sativa to treat several conditions like pain.
In the modern era, the research community, including health-care providers, have witnessed wide-scale changes in cannabis policy, legislation, and marketing, with a parallel increase in patient interest. A simple search in PubMed using “cannabis and pain” as keywords provides more than 2,400 articles, about 80% of which were published in the last 8-10 years. Several advancements have been achieved in understanding the complex chemistry of cannabis along with its multiple pharmacological activities.
Preclinical data have demonstrated evidence for the promising potential of cannabis for pain management, and the continuous rise in the prevalence of pain increases the urgency to translate this into clinical practice. Despite the large body of cannabis literature, researchers still need to find rigorous answers for the questions about the efficacy and safety of cannabis in treatment of certain disorders such as pain. In the current chapter, we seek to present a critical overview about the current knowledge on cannabis with special emphasis on pain-related disorders.”
“To test the hypothesis that genetic and pharmacological modulation of the classical cannabinoid type 1 (CB1) and 2 (CB2) receptors attenuate cancer-induced bone pain, we searched Medline, Web of Science and Scopus for relevant skeletal and non-skeletal cancer studies from inception to July 28, 2022. We identified 29 animal and 35 human studies. In mice, a meta-analysis of pooled studies showed that treatment of osteolysis-bearing males with the endocannabinoids AEA and 2-AG (mean difference [MD] – 24.83, 95% confidence interval [95%CI] – 34.89, – 14.76, p < 0.00001) or the synthetic cannabinoid (CB) agonists ACPA, WIN55,212-2, CP55,940 (CB1/2-non-selective) and AM1241 (CB2-selective) (MD – 28.73, 95%CI – 45.43, – 12.02, p = 0.0008) are associated with significant reduction in paw withdrawal frequency. Consistently, the synthetic agonists AM1241 and JWH015 (CB2-selective) increased paw withdrawal threshold (MD 0.89, 95%CI 0.79, 0.99, p < 0.00001), and ACEA (CB1-selective), AM1241 and JWH015 (CB2-selective) reduced spontaneous flinches (MD – 4.85, 95%CI – 6.74, – 2.96, p < 0. 00001) in osteolysis-bearing male mice. In rats, significant increase in paw withdrawal threshold is associated with the administration of ACEA and WIN55,212-2 (CB1/2-non-selective), JWH015 and AM1241 (CB2-selective) in osteolysis-bearing females (MD 8.18, 95%CI 6.14, 10.21, p < 0.00001), and treatment with AM1241 (CB2-selective) increased paw withdrawal thermal latency in males (mean difference [MD]: 3.94, 95%CI 2.13, 5.75, p < 0.0001), confirming the analgesic capabilities of CB1/2 ligands in rodents.
In human, treatment of cancer patients with medical cannabis (standardized MD – 0.19, 95%CI – 0.35, – 0.02, p = 0.03) and the plant-derived delta-9-THC (20 mg) (MD 3.29, CI 2.24, 4.33, p < 0.00001) or its synthetic derivative NIB (4 mg) (MD 2.55, 95%CI 1.58, 3.51, p < 0.00001) are associated with reduction in pain intensity.
Bioinformatics validation of KEGG, GO and MPO pathway, function and process enrichment analysis of mouse, rat and human data revealed that CB1 and CB2 receptors are enriched in a cocktail of nociceptive and sensory perception, inflammatory, immune-modulatory, and cancer pathways. Thus, we cautiously conclude that pharmacological modulators of CB1/2 receptors show promise in the treatment of cancer-induced bone pain, however further assessment of their effects on bone pain in genetically engineered animal models and cancer patients is warranted.”
“Purpose: This study elucidates the mechanism of the physiological effect of cannabidiol (CBD) by assessing its impact on lipopolysaccharide (LPS)-induced inflammation in RWPE-1 cells and prostatitis-induced by 17β-estradiol and dihydrotestosterone in a rat model, focusing on its therapeutic potential for chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS).
Materials and methods: RWPE-1 cells were stratified in vitro into three groups: (1) controls, (2) cells with LPS-induced inflammation, and (3) cells with LPS-induced inflammation and treated with CBD. Enzyme-linked immunosorbent assays and western blots were performed on cellular components and supernatants after administration of CBD. Five groups of six Sprague-Dawley male rats were assigned: (1) control, (2) CP/CPPS, (3) CP/CPPS and treated with 50 mg/kg CBD, (4) CP/CPPS and treated with 100 mg/kg CBD, and (5) CP/CPPS and treated with 150 mg/kg CBD. Prostatitis was induced through administration of 17β-estradiol and dihydrotestosterone. After four weeks of CBD treatment, a pain index was evaluated, and prostate tissue was collected for subsequent histologic examination and western blot analysis.
Results: CBD demonstrated efficacy in vivo for CP/CPPS and in vitro for inflammation. It inhibited the toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) pathway by activating the CB2 receptor, reducing expression of interleukin-6, tumor necrosis factor-alpha, and cyclooxygenase-2 (COX2) (p<0.01). CBD exhibited analgesic effects by activating and desensitizing the TRPV1 receptor.
Conclusions: CBD inhibits the TLR4/NF-κB pathway by activating the CB2 receptor, desensitizes the TRPV1 receptor, and decreases the release of COX2. This results in relief of inflammation and pain in patients with CP/CPPS, indicating CBD as a potential treatment for CP/CPPS.”
“Background: Cannabidiol (CBD) is the second most abundant pharmacologically active component present in Cannabis sp. Unlike Δ-9-tetrahydrocannabinol (THC), it has no psychotomimetic effects and has recently received significant interest from the scientific community due to its potential to treat anxiety and epilepsy. CBD has excellent anti-inflammatory potential and can be used to treat some types of inflammatory and neuropathic pain. In this context, the present study aimed to evaluate the analgesic mechanism of cannabidiol administered systemically for the treatment of neuropathic pain and determine the endogenous mechanisms involved with this analgesia.
Methods: Neuropathic pain was induced by sciatic nerve constriction surgery, and the nociceptive threshold was measured using the paw compression test in mice.
Results: CBD produced dose-dependent antinociception after intraperitoneal injection. Selective inhibition of PI3Kγ dose-dependently reversed CBD-induced antinociception. Selective inhibition of nNOS enzymes reversed the antinociception induced by CBD, while selective inhibition of iNOS and eNOS did not alter this antinociception. However, the inhibition of cGMP production by guanylyl cyclase did not alter CBD-mediated antinociception, but selective blockade of ATP-sensitive K+ channels dose-dependently reversed CBD-induced antinociception. Inhibition of S-nitrosylation dose-dependently and completely reversed CBD-mediated antinociception.
Conclusion: Cannabidiol has an antinociceptive effect when administered systemically and this effect is mediated by the activation of PI3Kγ as well as by nitric oxide and subsequent direct S-nitrosylation of KATP channels on peripheral nociceptors.”
