In vivo and in vitro anti-inflammatory activity evaluation of Lebanese Cannabis sativa L. ssp. indica (Lam.).

ETHNOPHARMACOLOGICAL RELEVANCE: Cannabis sativa L. is an aromatic annual herb belonging to the family Cannabaceae and it is widely distributed worldwide. Cultivation, selling, and consumption of cannabis and cannabis related products, regardless of its use, was prohibited in Lebanon until April 22, 2020. Nevertheless, cannabis oil has been traditionally used unlawfully for many years in Lebanon to treat diseases such as arthritis, diabetes, cancer and few neurological disorders. AIM OF THE STUDY: The present study aims to evaluate the phytochemical and anti-inflammatory properties of a cannabis oil preparation that is analogous to the illegally used cannabis oil in Lebanon. MATERIALS AND METHODS: Dried Cannabis flowers were extracted with ethanol without any purification procedures to simulate the extracts sold by underground dealers in Lebanon. GC/MS was performed to identify chemical components of the cannabis oil extract (COE). In vivo anti-inflammatory effect of COE was evaluated by using carageenan- and formalin-induced paw edema rat models. TNF-α production were determined by using LPS-activated rat monocytes. Anti-inflammatory markers were quantified using Western blot. RESULTS: Chemical analysis of COE revealed that cannabidiol (CBD; 59.1%) and tetrahydrocannabinol (THC; 20.2%) were found to be the most abundant cannabinoids.Various monoterpenes (α-Pinene, Camphene, ß-Myrecene and D-Limonene) and sesquiterpenes (ß-Caryophyllene, α-Bergamotene, α-Humelene, Humulene epoxide II, and Caryophyllene oxide) were identified in the extract. Results showed that COE markedly suppressed the release of TNF-α in LPS-stimulated rat monocytes. Western blot analysis revealed that COE significantly inhibited LPS-induced COX-2 and i-NOS protein expressions and blocked the phosphorylation of MAPKs, specifically that of extracellular signal-regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK) and p38 MAPK. COE displayed a significant inhibition of paw edema in both rat models. Histopathological examination revealed that COE reduced inflammation and edema in chronic paw edema model. CONCLUSION: The current findings demonstrate that COE possesses remarkable in vivo and in vitro anti-inflammatory activities which support the traditional use of the Lebanese cannabis oil extract in the treatment of various inflammatory diseases including arthritis.

ß-2-himachalen-6-ol protects against skin cancer development in vitro and in vivo.

BACKGROUND: Previous studies in our laboratory showed that Daucus carota oil extract (DCOE) possesses remarkable in-vitro anticancer activity and antitumour promoting effect against DMBA/TPA skin carcinogenesis in mice. Chemical analysis of DCOE led to the isolation of the ß-2-himachalen-6-ol (HC), major sesquiterpene with a potent anticancer activity against various colon, breast, brain and skin cancer cells. This study investigated the anticancer activity of HC against invasive epidermal squamous cell carcinoma cells and evaluated its effect in a DMBA/TPA skin carcinogenesis Balb/c murine model. METHODS: HaCaT-ras II-4 epidermal squamous cells were treated with HC (1, 5, 10, 25 and 50 µg/ml), and cell viability was evaluated with WST 1 assay kit. Cell cycle analysis was carried out by flow cytometry, and pro/anti-apoptotic proteins were measured using Western blot. The effect of topical and intraperitoneal (IP) treatment with HC in mice was assessed using the DMBA/TPA skin carcinogenesis model. Cisplatin (2.5 mg/kg; IP) was used as a positive control. Papilloma incidence, yield and volume were monitored, and isolated papillomas were assessed for their pro/anti-apoptotic proteins and morphology. RESULTS: ß-2-himachalen-6-ol showed a dose-dependent decrease in cell survival with an IC50 and IC90 of 8 and 30 µg/ml, respectively. Flow cytometry analysis revealed that treatment with 10 µg/ml HC significantly increased the number of cells undergoing late apoptosis (28%), while 25 µg/ml caused a larger cell shift towards late apoptosis (46.6%) and necrosis (39%). A significant decrease in protein levels of p53 and Bcl-2 and a significant increase in p21 and Bax were observed. Also, there was a significant decrease in p-Erk and p-Akt protein levels. The treatment of mice (IP and topical) with HC caused a significant decrease in papilloma yield, incidence and volume. Similar effects were observed with cisplatin treatment, but HC-treated groups exhibited twofold to threefold increase in survival rates. Similar patterns in the pro- and anti-apoptotic proteins were observed in mice treated with HC, except for a significant increase in p53 protein. CONCLUSIONS: In conclusion, HC treatment induced cell cycle arrest (low dose) and promoted apoptosis partly via inhibition of the MAPK/ERK and PI3K/AKT pathways with no significant toxicity to laboratory mice.