Sesquiterpene Alcohol Cedrol Chemosensitizes Human Cancer Cells and Suppresses Cell Proliferation by Destabilizing Plasma Membrane Lipid Rafts

Cedrol alleviates postmenopausal osteoporosis in rats through inhibiting the activation of the NF-κB signaling pathway

Pharmacological studies have shown that Cedrol (CE) exhibits extensive biological activities, including anti-inflammatory and analgesic. Moreover, it can inhibit the NF-κB pathway and the expression of various associated proteins. This study aimed to investigate the role of CE in postmenopausal osteoporosis. The results showed that intragastric administration of CE (10 and 20 mg/kg) significantly improved the bone microstructure damage and increased bone mineral density, trabecular bone volume, and bone trabecular thickness in ovariectomized (OVX) rats (p < 0.05). CE treatment additionally made a well-organized arrangement of bone trabeculae and improved its thickness and density. Compared with the OVX group, the levels of tartrate-resistant acid phosphatase from 5b and C-terminal telopeptide of type I collagen were significantly reduced by 42.75% and 49.27% in the OVX + CE rats (p < 0.05). TRAP staining visually showed that the number of osteoclasts in the femur tissue of CE-treated rats was less than that of the OVX group. The expressions of nuclear factor of activated T-cells, cytoplasmic 1, acid phosphatase 5, and cathepsin K in OVX + CE rats were significantly decreased by 51.61%, 46.07%, and 50.34% compared to the OVX group (p < 0.01). In addition, CE intervention effectively reduced the phosphorylation levels of P65 and IκBα and inhibited the NF-κB signaling pathway. Meanwhile, CE diminished the number of multinucleated osteoclasts induced by receptor activator for nuclear factor-κB ligand and hindered cell fusion as well as nuclear translocation of osteoclast precursor cells P65. In conclusion, CE inhibits osteoclastogenesis by suppressing the activation of the NF-κB signaling pathway, thereby alleviating postmenopausal osteoporosis.

Ginsenosides Inhibit the Proliferation of Lung Cancer Cells and Suppress the Rate of Metastasis by Modulating EGFR/VEGF Signaling Pathways

Ginsenosides Rg3 and Rg5 obtained from Panax (ginseng) have shown significant anticancer activity via the PI3K-Akt signaling pathway. This study evaluated the anticancer and antimetastatic effects of a combination of Rg3 and Rg5 on lung cancer cells. A combination of Rg3 and Rg5 was treated for lung cancer cell line A549 and human lung tumor xenograft mouse model, and anti-metastatic effects on Matrigel plug implantation in mice. The combination of Rg3 and Rg5 showed potent antiproliferative effects on A549 cells with IC50 values of 44.6 and 36.0 μM for Rg3 and Rg5 respectively. The combination of Rg3 and Rg5 (30 µM each) showed 48% cell viability as compared to Rg3 (72% viability) and Rg5 (64% viability) at 30 µM concentrations. The combination of Rg3 and Rg5 induced apoptosis in A549 cells characterized by activation of caspase-9 and caspase-3 and cleavage of PARP, as well as suppression of the autophagic marker LC3A/B. The antitumoral potentials of the combination of Rg3 and Rg5 were ascertained in a lung tumor xenograft mouse model with high efficacy as compared to individual ginsenosides. The metastasislimiting properties of the combination of Rg3 and Rg5 were assessed in Matrigel plug implantation in mice which showed the potent efficacy of the combination as compared to individual ginsenoside. Mechanistically, the combination of Rg3 and Rg5 inhibited the expression of PI3K/Akt/mTOR and EGFR/VEGF signaling pathways in lung cancer cells. Results suggest that the combination of Rg3 and Rg5 suppressed the tumor cell proliferation in lung cancer cells and limited the rate of metastasis which further suggest that the combination has a significant effect as compared to the administration of single ginsenoside.

Downregulation of VEGFR2 signaling by cedrol abrogates VEGF‑driven angiogenesis and proliferation of glioblastoma cells through AKT/P70S6K and MAPK/ERK1/2 pathways

Cedrol is a sesquiterpene alcohol isolated from Cedrus atlantica, which has been traditionally used in aromatherapy and has anticancer, antibacterial and antihyperalgesic effects. One characteristic of glioblastoma (GB) is the overexpression of vascular endothelial growth factor (VEGF), which induces a high degree of angiogenesis. Although previous studies have reported that cedrol inhibits GB growth by inducing DNA damage, cell cycle arrest and apoptosis, its role in angiogenesis remains unclear. The aim of the present study was to investigate the effects of cedrol on VEGF-induced angiogenesis of human umbilical vein endothelial cells (HUVECs). HUVECs were treated with 0-112 µM cedrol and 20 ng/ml VEGF for 0-24 h, and then anti-angiogenic activation of cedrol was determined by MTT assay, wound healing assay, Boyden chamber assay, tube formation assay, semi-quantitative reverse transcription-PCR and western blotting. These results demonstrated that cedrol treatment inhibited VEGF-induced cell proliferation, migration and invasion in HUVECs. Furthermore, cedrol prevented VEGF and DBTRG-05MG GB cells from inducing capillary-like tube formation in HUVECs and decreased the number of branch points formed. Moreover, cedrol downregulated the phosphorylation of VEGF receptor 2 (VEGFR2) and the expression levels of its downstream mediators AKT, ERK, VCAM-1, ICAM-1 and MMP-9 in HUVECs and DBTRG-05MG cells. Taken together, these results demonstrated that cedrol exerts anti-angiogenic effects by blocking VEGFR2 signaling, and thus could be developed into health products or therapeutic agents for the prevention or treatment of cancer and angiogenesis-related diseases in the future.

Mechanisms of Arachidonic Acid In Vitro Tumoricidal Impact

To promote the potential of arachidonic acid (ARA) for cancer prevention and management, experiments were implemented to disclose the mechanisms of its tumoricidal action. Hepatocellular, lung, and breast carcinoma and normal hepatocytes cell lines were exposed to 0 or 50 μM ARA for 30 min and then assessed for proliferative capacity, surface membrane-associated sphingomyelin (SM) content, neutral sphingomyelinase (nSMase) activity, beta 2 microglobulin (β2 m) expression, and ceramide (Cer) levels. Reactive oxygen species (ROS) content and caspase 3/7 activity were evaluated. Exposure to ARA for 30 min led to impairment of the tumor cells' proliferative capacity and revealed that the different cell lines display remarkably similar surface membrane SM content but diverse responses to ARA treatment. Arachidonic acid tumoricidal impact was shown to be associated with nSMase activation, exposure of cell surface membrane β2 m to antibody binding, and hydrolysis of SM to Cer, which accumulated on the cell surface and in the cytosol. The ARA and Cer-mediated inhibition of tumor cell viability appeared to be independent of ROS generation or caspase 3/7 activation. The data were compared and contrasted to findings reported in the literature on ARA tumoricidal mechanisms.

Reprogrammed Lipid Metabolism and the Lipid-Associated Hallmarks of Colorectal Cancer

Simple Summary

Colorectal cancer (CRC) is the third-most diagnosed cancer and the second-leading cause of cancer-related deaths worldwide. Limitations in early and accurate diagnosis of CRC gives rise to poor patient survival. Advancements in analytical techniques have improved our understanding of the cellular and metabolic changes occurring in CRC and potentiate avenues for improved diagnostic and therapeutic strategies. Lipids are metabolites with important biological functions; however, their role in CRC is poorly understood. Here, we provide an in-depth review of the recent literature concerning lipid alterations in CRC and propose eight lipid metabolism-associated hallmarks of CRC.

Abstract

Lipids have diverse structures, with multifarious regulatory functions in membrane homeostasis and bioenergetic metabolism, in mediating functional protein–lipid and protein–protein interactions, as in cell signalling and proliferation. An increasing body of evidence supports the notion that aberrant lipid metabolism involving remodelling of cellular membrane structure and changes in energy homeostasis and signalling within cancer-associated pathways play a pivotal role in the onset, progression, and maintenance of colorectal cancer (CRC) and their tumorigenic properties. Recent advances in analytical lipidome analysis technologies have enabled the comprehensive identification and structural characterization of lipids and, consequently, our understanding of the role they play in tumour progression. However, despite progress in our understanding of cancer cell metabolism and lipidomics, the key lipid-associated changes in CRC have yet not been explicitly associated with the well-established ‘hallmarks of cancer’ defined by Hanahan and Weinberg. In this review, we summarize recent findings that highlight the role of reprogrammed lipid metabolism in CRC and use this growing body of evidence to propose eight lipid metabolism-associated hallmarks of colorectal cancer, and to emphasize their importance and linkages to the established cancer hallmarks.

Induction of Cell Cycle Arrest, Apoptosis, and Reducing the Expression of MCM Proteins in Human Lung Carcinoma A549 Cells by Cedrol, Isolated from Juniperus chinensis

Proteins related to DNA replication have been proposed as cancer biomarkers and targets for anticancer agents. Among them, minichromosome maintenance (MCM) proteins, often overexpressed in various cancer cells, are recognized both as notable biomarkers for cancer diagnosis and as targets for cancer treatment. Here, we investigated the activity of cedrol, a single compound isolated from Juniperus chinensis, in reducing the expression of MCM proteins in human lung carcinoma A549 cells. Remarkably, cedrol also strongly inhibited the expression of all other MCM protein family members in A549 cells. Moreover, cedrol treatment reduced cell viability in A549 cells, accompanied by cell cycle arrest at the G1 phase, and enhanced apoptosis. Taken together, this study broadens our understanding of how cedrol executes its anticancer activity while demonstrating that cedrol has potential application in the treatment of human lung cancer as an inhibitor of MCM proteins.

The Complexity of Sesquiterpene Chemistry Dictates Its Pleiotropic Biologic Effects on Inflammation

Sesquiterpenes (SQs) are volatile compounds made by plants, insects, and marine organisms. SQ have a large range of biological properties and are potent inhibitors and modulators of inflammation, targeting specific components of the nuclear factor-kappaB (NF-κB) signaling pathway and nitric oxide (NO) generation. Because SQs can be isolated from over 1600 genera and 2500 species grown worldwide, they are an attractive source of phytochemical therapeutics. The chemical structure and biosynthesis of SQs is complex, and the SQ scaffold represents extraordinary structural variety consisting of both acyclic and cyclic (mono, bi, tri, and tetracyclic) compounds. These structures can be decorated with a diverse range of functional groups and substituents, generating many stereospecific configurations. In this review, the effect of SQs on inflammation will be discussed in the context of their complex chemistry. Because inflammation is a multifactorial process, we focus on specific aspects of inflammation: the inhibition of NF-kB signaling, disruption of NO production and modulation of dendritic cells, mast cells, and monocytes. Although the molecular targets of SQs are varied, we discuss how these pathways may mediate the effects of SQs on inflammation.

Cedrol restricts the growth of colorectal cancer in vitro and in vivo by inducing cell cycle arrest and caspase-dependent apoptotic cell death

Background: Cedrol is a natural sesquiterpene alcohol found in Cedrus atlantica, which has been proven to have a broad spectrum of biological activities, such as antimicrobial, anti-inflammatory, analgesic, anxiolytic, and anti-cancer effects. However, the underlying anticancer mechanisms and in vivo inhibitory effects of cedrol on colorectal cancer (CRC) have not been elucidated. In the present study, we investigated the anti-CRC potential of cedrol using in vitro and in vivo models. Methods: The effects of cedrol on cell viability, cell cycle progression, and apoptosis of HT-29 and CT-26 cells were detected by MTT, flow cytometry, and TUNEL assays. Western blotting was used to measure protein expression for molecular signaling analyses. Results: Cedrol inhibited HT-29 and CT-26 cell proliferation in a time- and dose-dependent manner, with IC₅₀ values of 138.91 and 92.46 µM, respectively. Furthermore, cedrol induced cell cycle arrest at the G0/G1 phase by regulating the expression of cell cycle regulators, such as CDK4 and cyclin D1, and triggered apoptosis through extrinsic (FasL/caspase-8) and intrinsic (Bax/caspase-9) pathways. In addition, cedrol in combination with the clinical drug 5-fluorouracil exhibited synergistic inhibitory effects on CRC cell growth. Importantly, cedrol treatment suppressed the progression of CRC and improved the survival rate of animals at a well-tolerated dose. Conclusion: These results suggest that cedrol has an anti-cancer potential via induction of cell cycle arrest and apoptosis, and it could be considered as an effective agent for CRC therapy.

Innate Immunomodulatory Activity of Cedrol, a Component of Essential Oils Isolated from Juniperus Species

Little is known about the immunomodulatory activity of essential oils isolated from Juniperus species. Thus, we isolated essential oils from the cones and leaves of eight juniper species found in Montana and in Kazakhstan, including J. horizontalis, J. scopolorum, J. communis, J. seravschanica, J. sabina, J. pseudosabina, J. pseudosabina subsp. turkestanica, and J. sibirica. We report here the chemical composition and innate immunomodulatory activity of these essential oils. Compositional analysis of the 16 samples of Juniper essential oils revealed similarities and differences between our analyses and those previously reported for essential oils from this species. Our studies represent the first analysis of essential oils isolated from the cones of four of these Juniper species. Several essential oil samples contained high levels of cedrol, which was fairly unique to three Juniper species from Kazakhstan. We found that these essential oils and pure (+)-cedrol induced intracellular Ca²⁺ mobilization in human neutrophils. Furthermore, pretreatment of human neutrophils and N-formyl peptide receptor 1 and 2 (FPR1 and FPR2) transfected HL60 cells with these essential oils or (+)-cedrol inhibited agonist-induced Ca²⁺ mobilization, suggesting these responses were desensitized by this pretreatment. In support of this conclusion, pretreatment with essential oils from J. seravschanica cones (containing 16.8% cedrol) or pure (+)-cedrol inhibited human neutrophil chemotaxis to N-formyl peptide. Finally, reverse pharmacophore mapping predicted several potential kinase targets for cedrol. Thus, our studies have identified cedrol as a novel neutrophil agonist that can desensitize cells to subsequent stimulation by N-formyl peptide.