Antinociceptive Effect of a p-Cymene/ß-Cyclodextrin Inclusion Complex in a Murine Cancer Pain Model: Characterization Aided through a Docking Study.

Pain is one of the most prevalent and difficult to manage symptoms in cancer patients, and conventional drugs present a range of adverse reactions. The development of ß-cyclodextrins (ß-CD) complexes has been used to avoid physicochemical and pharmacological limitations due to the lipophilicity of compounds such as p-Cymene (PC), a monoterpene with antinociceptive effects. Our aim was to obtain, characterize, and measure the effect of the complex of p-cymene and ß-cyclodextrin (PC/ß-CD) in a cancer pain model. Initially, molecular docking was performed to predict the viability of complex formation. Afterward, PC/ß-CD was obtained by slurry complexation, characterized by HPLC and NMR. Finally, PC/ß-CD was tested in a Sarcoma 180 (S180)-induced pain model. Molecular docking indicated that the occurrence of interaction between PC and ß-CD is favorable. PC/ß-CD showed complexation efficiency of 82.61%, and NMR demonstrated PC complexation in the ß-CD cavity. In the S180 cancer pain model, PC/ß-CD significantly reduced the mechanical hyperalgesia, spontaneous nociception, and nociception induced by non-noxious palpation at the doses tested (p < 0.05) when compared to vehicle differently from free PC (p > 0.05). Therefore, the complexation of PC in ß-CD was shown to improve the pharmacological effect of the drug as well as reducing the required dose.

γ-Terpinene complexed with ß-cyclodextrin attenuates spinal neuroactivity in animals with cancer pain by Ca2+ channel block.

OBJECTIVES: Considering that γ-terpinene (γ-TPN) is a monoterpene found in Cannabis oil, with high lipophilicity and limited pharmacokinetics, our objective was to evaluate whether its complexation in ß-cyclodextrin (γ-TPN/ß-CD) could improve its physicochemical properties and action on cancer pain, as well as verify the mechanisms of action involved. METHODS: The γ-TPN/ß-CD was prepared and submitted to physicochemical characterization. Animals with sarcoma 180 were treated (vehicle, γ-TPN 50 mg/kg, γ-TPN/ß-CD 5 mg/kg or morphine) and assessed for hyperalgesia, TNF-α and IL-1ß levels, iNOS and c-Fos activity. The effects of γ-TPN on calcium channels were studied by patch-clamp and molecular docking. RESULTS: ß-CD improved the physicochemical properties and prolonged the anti-hyperalgesic effect of γ-TPN. This compound also reduced the levels of IL-1ß, TNF-α and iNOS in the tumour, and c-Fos protein in the spinal cord. In addition, it reduced Ca2+ current, presenting favourable chemical interactions with different voltage-dependent calcium channels. CONCLUSION: These results indicate that the complexation of γ-TPN into ß-CD increases its stability and time effect, reducing spinal neuroactivity and inflammation by blocking calcium channels.

Protective effects of flavonoid composition rich P. subpeltata Ortega. on indomethacin induced experimental ulcerative colitis in rat models of inflammatory bowel diseases.

ETHNOPHARMACOLOGICAL RELEVANCE: Polyphenolics (flavonoid and phenolic) rich plants are the effective source for the treatment of acute and chronic degenerative diseases including inflammatory bowel disease. OBJECTIVE: This study was aimed to examine the effects of polyphenolics rich leaf acetone extract of P. subpeltata against the indomethacin induced ulcerative colitis in rats. MATERIALS AND METHODS: Two consecutive days administration of indomethacin produced chronic inflammation in GIT tissues of rats. Further, the plant extract 200 and 400 mg/kg treatment were continued until 11th day. Then hematological, enzymatic antioxidants, MPO and histological evaluations were analyzed. Moreover, the extracts were treated with RAW267.4 cells for the cytotoxicity, NO and TNF-α analysis. RESULTS: The obtained results revealed, that higher dose of the plant extract dropped neutrophil infiltration followed by inhibiting the MPO enzyme levels and controls the enzymatic antioxidants such as SOD, CAT, GSH and LPO. RAW cells study also proved that the plant extract effectively inhibits NO and TNF-α production. CONCLUSIONS: Thus, these results suggest that P. subpeltata extract may have therapeutic potential for the treatment of IBD although further clinical research is still warranted.

Anti-hyperalgesic and anti-inflammatory effects of citral with ß-cyclodextrin and hydroxypropyl-ß-cyclodextrin inclusion complexes in animal models.

Citral (CIT) is a monoterpene formed by the geranial and neral stereoisomers. CIT is the major compound of Cymbopogon citratus essential oil, commonly known as "lemongrass", and has demonstrated potential antihyperalgesic, anti-nociceptive and anti-inflammatory effects. However, CIT shows high volatility, low solubility in water and consequent low bioavailability, which limits its use. Therefore, the aim of this study was to evaluate cell viability, anti-hyperalgesic and anti-inflammatory effects of inclusion complexes of CIT on ß-cyclodextrin (ß-CD) and hydroxypropyl-ß-cyclodextrin (HP-ß-CD). Initially, physical mixture (PM) and freeze-dried inclusion (FD) complexes of CIT/ß-CD and CIT/HP-ß-CD were obtained in the molar ratio (1:1). The samples were characterized by DSC, TG/DTG, FT-IR, XRD, SEM and the complexation efficiency were performed by HPLC. Cell viability assay was performed by rezasurin reduction technique in J774 macrophages cell line. The motor activity through rota rod apparatus, mechanical hyperalgesia and pleurisy induced by carrageenan were evaluated in mice. The complexation of CIT was evidenced with ß-CD and HP-ß-CD by the characterization techniques analyzed. The complexation efficiency of CIT/ß-CD and CIT/HP-ß-CD were 78.6% and 71.7%, respectively. The CIT, CIT/ß-CD and CIT/HP-ß-CD showed cell viability in macrophages and did not interfere in the motor activity of mice. Besides that, the samples demonstrated antihyperalgesic and anti-inflammatory activity due to the reduction in total leukocytes and TNF-α levels. However, CIT/ß-CD has better pharmacological effects among the three samples evaluated. Therefore, CIT/ß-CD has potential for the development of products to treat inflammatory and pain reactions.

Carvacrol/ß-cyclodextrin inclusion complex inhibits cell proliferation and migration of prostate cancer cells.

Carvacrol, a phenolic monoterpene derived from thyme oil has gained wide interest recently because of its anticancer activities. To improve the solubility of carvacrol, the formation of inclusion complexes with ß-cyclodextrin was performed by ultrasound and freeze-drying methods and characterized using thermal analysis, FTIR, XRD, SEM, NMR and HPLC analysis. From these results, carvacrol was successfully complexed within ß-cyclodextrin cavity. Moreover, HPLC analysis demonstrated a higher entrapment efficiency for freeze-drying method (81.20 ±â€¯0.52%) in contrast to ultrasound method (34.02 ±â€¯0.67%). Hence, freeze-drying inclusion complex was evaluated for its antiproliferative effect and cytotoxicity against prostate cancer cell line (PC3) in vitro. Further, freeze-drying complex led to a dose-dependent inhibition in tumor cell growth in 2D and 3D cell culture systems. Altogether, the inclusion of carvacrol in ß-cyclodextrin led to the formation of stable complexes with potent antiproliferative effects against PC3 cells, in vitro. Such an improved cytotoxic effect can be attributed to the enhanced the aqueous solubility and bioavailability of carvacrol by effective complexation in ß-cyclodextrin.