cytochrome-c-t and honokiol

To investigate the effect of honokiol (HKL) for reducing doxorubicin (DOX)-induced cardiotoxicity in H9c2 cells and the underlying mechanisms.. H9c2 cells were divided into control group, DOX group, HKL + DOX group, and HKL+compound C+DOX group. After 24 h of corresponding treatment, the cells were examined for morphological changes and cell viability using CCK-8 assay. The mRNA expressions of the inflammatory factors including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) were detected by RT-PCR, and the protein levels of cleaved caspase-3, cytochrome c, NOD-like receptor pyrin domain containing 3 (NLRP3), caspase-1, apoptosis-associated speck-like protein containing a CARD (ASC), p-AMPK and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) were detected with Western blotting; the expressions of NLRP3 and p-AMPK also detected with immunofluorescence staining.. DOX treatment caused swelling and significantly lowered the viability of H9c2 cells (. HKL can alleviate DOX-induced cardiotoxicity by inhibiting pyroptosis in H9c2 cells, and this effect is mediated by activation of AMPK to regulate Nrf2 signaling.

Topics: Allyl Compounds; AMP-Activated Protein Kinases; Biphenyl Compounds; Cardiotoxicity; Caspase 3; Cytochromes c; Doxorubicin; Humans; Interleukin-6; Myocytes, Cardiac; NF-E2-Related Factor 2; NLR Family, Pyrin Domain-Containing 3 Protein; Phenols; Pyroptosis; RNA, Messenger; Tumor Necrosis Factor-alpha

To investigate the effect of honokiol on demyelination after compressed spinal cord injury (CSCI) and it's possible mechanism.. Animal experiment study.. Institute of Neuroscience of Chongqing Medical University.. Total of 69 Sprague-Dawley (SD) rats were randomly divided into 3 groups: sham group (n=15), honokiol group (n=27) and vehicle group (n=27). After established CSCI model by a custom-made compressor successfully, the rats of sham group were subjected to the limited laminectomy without compression; the rats of honokiol group were subjected to CSCI surgery and intraperitoneal injection of 20 mg/kg honokiol; the rats of vehicle group were subjected to CSCI surgery and intraperitoneal injection of an equivalent volume of saline.. In the vehicle group, the rats became paralyzed and spastic after injury, and the myelin sheath became swollen and broken down along with decreased number of myelinated nerve fibers. Western blot analysis manifested that active caspase-3, caspase-12 and cytochrome C began to increase 1 d after injury while the expression of MBP decreased gradually. After intervened with honokiol for 6 days, compared with the vehicle group, the locomotor function and the pathomorphological changes of myelin sheath of the CSCD rats were improved with obviously decreased expression of active caspase-3, caspase-12 and cytochrome C.. Honokiol may improve locomotor function and protect neural myelin sheat from demyelination via prevention oligodendrocytes (OLs) apoptosis through mediate endoplasmic reticulum (ER)-mitochondria pathway after CSCI.

Topics: Animals; Apoptosis; Biphenyl Compounds; Caspase 12; Caspase 3; Cytochromes c; Demyelinating Diseases; Endoplasmic Reticulum; Humans; Lignans; Mitochondria; Myelin Sheath; Rats; Rats, Sprague-Dawley; Spinal Cord; Spinal Cord Injuries

Temozolomide (TMZ) is a first-line chemotherapeutic drug for malignant gliomas. Nonetheless, TMZ-induced side effects and drug resistance remain challenges. Our previous study showed the suppressive effects of honokiol on growth of gliomas.. This study was further aimed to evaluate if honokiol could enhance TMZ-induced insults toward malignant glioma cells and its possible mechanisms.. Human U87 MG glioma cells were exposed to TMZ, honokiol, and a combination of TMZ and honokiol. Cell survival, apoptosis, necrosis, and proliferation were successively assayed. Fluorometric substrate assays were conducted to determine activities of caspase-3, -6, -8, and -9. Levels of Fas ligand, Bax, and cytochrome c were immunodetected. Translocation of Bax to mitochondria were examined using confocal microscopy. Mitochondrial function was evaluated by assaying the mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and complex I enzyme activity. Caspase-6 activity was suppressed using specific peptide inhibitors. The honokiol-induced effects were further confirmed using human U373 MG and murine GL261 cells.. Exposure of human U87 MG glioma cells to honokiol significantly increased TMZ-induced DNA fragmentation and cell apoptosis. Interestingly, honokiol enhanced intrinsic caspase-9 activity without affecting extrinsic Fas ligand levels and caspase-8 activity. Sequentially, TMZ-induced changes in Bax translocation, the MMP, mitochondrial complex I enzyme activity, intracellular ROS levels, and cytochrome c release were enhanced by honokiol. Consequently, honokiol amplified TMZ-induced activation of caspases-3 and -6 in human U87 MG cells. Fascinatingly, suppressing caspase-6 activity concurrently decreased honokiol-induced DNA fragmentation and cell apoptosis. The honokiol-involved improvement in TMZ-induced intrinsic apoptosis was also confirmed in human U373 MG and murine GL261 glioma cells.. This study showed that honokiol can enhance TMZ-induced apoptotic insults to glioma cells via an intrinsic mitochondrion-dependent mechanism. Our results suggest the therapeutic potential of honokiol to attenuate TMZ-induced side effects.

Topics: Animals; Apoptosis; Biphenyl Compounds; Caspases; Cell Line, Tumor; Cell Survival; Cytochromes c; Dacarbazine; DNA Fragmentation; Drugs, Chinese Herbal; Fas Ligand Protein; Glioma; Humans; Lignans; Membrane Potential, Mitochondrial; Mice; Mitochondria; Reactive Oxygen Species; Signal Transduction; Temozolomide

This study aims to investigate the effects of honokiol on proliferation, cell cycle, and apoptosis in tumor necrosis factor (TNF)-α-induced rat aortic smooth muscle cells (RASMCs). We found that honokiol treatment showed potent inhibitory effects on TNF-α-induced RASMC proliferation, which were associated with G0/G1 cell cycle arrest and downregulation of cell cycle-related proteins, including cyclin D1, cyclin E, cyclin-dependent kinase (CDK)2 and CDK4. Furthermore, honokiol treatment led to the release of cytochrome c into cytosol and a loss of mitochondrial membrane potential (ΔΨm), as well as a decrease in the expression of Bcl-2 and an increase in the expression of Bax. Treatment with honokiol also reduced TNF-α-induced phosphorylation of p38, extracellular signal-regulated kinase 1/2, and c-Jun N-terminal kinase. Taken together, our results suggest that honokiol suppresses TNF-α-stimulated RASMC proliferation via caspase- and mitochondria-dependent apoptosis and highlight the therapeutic potential of honokiol in the prevention of cardiovascular diseases.

Topics: Animals; Aorta; Apoptosis; bcl-2-Associated X Protein; Biphenyl Compounds; Caspases; Cell Proliferation; Cell Survival; Cells, Cultured; Cyclin D1; Cyclin E; Cyclin-Dependent Kinase 2; Cyclin-Dependent Kinase 4; Cytochromes c; Drugs, Chinese Herbal; Enzyme Inhibitors; Extracellular Signal-Regulated MAP Kinases; G1 Phase Cell Cycle Checkpoints; JNK Mitogen-Activated Protein Kinases; Lignans; Male; Membrane Potential, Mitochondrial; Mitochondria; Muscle, Smooth, Vascular; Nitric Oxide Synthase; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Sprague-Dawley; Signal Transduction; Tumor Necrosis Factor-alpha

Neuroblastomas, an embryonic cancer of the sympathetic nervous system, often occur in young children. Honokiol, a small-molecule polyphenol, has multiple therapeutic effects and pharmacological activities. This study was designed to evaluate whether honokiol could pass through the blood-brain barrier (BBB) and induce death of neuroblastoma cells and its possible mechanisms. Primary cerebral endothelial cells (CECs) prepared from mouse brain capillaries were cultured at a high density for 4 days, and these cells formed compact morphologies and expressed the ZO-1 tight-junction protein. A permeability assay showed that the CEC-constructed barrier obstructed the passing of FITC-dextran. Analyses by high-performance liquid chromatography and the UV spectrum revealed that honokiol could traverse the CEC-built junction barrier and the BBB of ICR mice. Exposure of neuroblastoma neuro-2a cells and NB41A3 cells to honokiolinduced cell shrinkage and decreased cell viability. In parallel, honokiol selectively induced DNA fragmentation and cell apoptosis rather than cell necrosis. Sequential treatment of neuro-2a cells with honokiol increased the expression of the proapoptotic Bax protein and its translocation from the cytoplasm to mitochondria. Honokiol successively decreased the mitochondrial membrane potential but increased the release of cytochrome c from mitochondria. Consequently, honokiol induced cascade activation of caspases-9, -3, and -6. In comparison, reducing caspase-6 activity by Z-VEID-FMK, an inhibitor of caspase-6, simultaneously attenuated honokiol-induced DNA fragmentation and cell apoptosis. Taken together, this study showed that honokiol can pass through the BBB and induce apoptotic insults to neuroblastoma cells through a Bax-mitochondrion-cytochrome c-caspase protease pathway. Therefore, honokiol may be a potential candidate drug for treating brain tumors.

Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; bcl-2-Associated X Protein; Biphenyl Compounds; Blood-Brain Barrier; Brain Neoplasms; Caspases; Cell Line, Tumor; Cell Survival; Cells, Cultured; Cytochromes c; DNA Fragmentation; Endothelial Cells; Humans; Lignans; Membrane Potential, Mitochondrial; Mice; Mice, Inbred ICR; Mitochondria; Neuroblastoma; Proto-Oncogene Proteins c-bcl-2; Tight Junctions

Melanoma continues to be a therapeutic challenge for the medical community owing to the scarcity of effective agents available to treat the disease. Honokiol, a traditional Chinese herb, has been proven to have anti-cancer effects in various cell types, therefore we hypothesized it may have similar cytotoxic capabilities against melanoma cells in vitro.. Two cell lines, SK-MEL2 and MeWo, were grown in culture and exposed to increasing doses of Honokiol. Cell proliferation, cytochrome c release into the cytosol, intra-cellular caspase activity, and mitochondrial depolarization were then evaluated after treatment with honokiol.. Melanoma cells in culture underwent cell death, had increased cytosolic cytochrome c, showed greater caspase activity, and demonstrated increased mitochondrial depolarization after treatment when compared to controls.. It appears that honokiol is an effective inhibitor of cultured human melanoma cells.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Biphenyl Compounds; Blotting, Western; Caspases; Cell Proliferation; Cytochromes c; Drugs, Chinese Herbal; Enzyme-Linked Immunosorbent Assay; Humans; In Vitro Techniques; Lignans; Melanoma; Tumor Cells, Cultured

To study the effects of xanthohumol (XN), a flavonoid found in hops (Humulus lupulus) and honokiol (HK), a lignan isolated from Magnolia officinalis, alone and in combination, on apoptotic signaling in 3T3-L1 adipocytes.. 3T3-L1 mature adipocytes were incubated with various concentrations of XN and HK alone and in combination. Viability and apoptosis were quantified using an MTS-based cell viability assay and single-stranded DNA assay, respectively. Expression of apoptosis related proteins including cleaved poly(ADP-ribose) polymerase (PARP), cytochrome c, Bcl-2, caspase-3/7, phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and Akt was analyzed by western blotting.. Combinations of XN and HK significantly decreased viability and induced apoptosis in a dose-dependent manner and more than the additive responses to XN and HK alone. Western blot analysis showed an increase in cleaved PARP and cytochrome c release and decrease in expression of Bcl-2 protein by XN plus HK, whereas XN and HK individually had no effect. Furthermore, the combination of XN and HK activated PTEN and inactivated Akt by decreasing levels of phosphorylated PTEN and phosphorylated Akt.. We demonstrated that although XN and HK showed little or no effect as individual compounds, in combination (XN plus HK) they showed enhanced activity in inducing apoptosis via the cytochrome c/caspase-3/PARP and PTEN/Akt pathways in 3T3-L1 adipocytes.

Topics: 3T3-L1 Cells; Adipocytes; Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Biphenyl Compounds; Caspase 3; Cell Survival; Cytochromes c; Dose-Response Relationship, Drug; Drug Synergism; Flavonoids; Lignans; Mice; Poly (ADP-Ribose) Polymerase-1; Poly(ADP-ribose) Polymerases; Propiophenones; Proto-Oncogene Proteins c-akt; PTEN Phosphohydrolase; Signal Transduction

Honokiol, a compound extracted from Chinese medicinal herb Magnolia officinalis, has several biological effects. However, its protective effects against endothelial injury remain unclarified. In this study, we examined whether honokiol prevented oxidized low-density lipoprotein (oxLDL)-induced vascular endothelial dysfunction. Incubation of oxLDL with honokiol (2.5-20 microM) inhibited copper-induced oxidative modification as demonstrated by diene formation, thiobarbituric acid reactive substances (TBARS) assay and electrophoretic mobility assay. Expression of adhesion molecules (ICAM, VCAM and E-selectin) and endothelial NO synthase (eNOS) affected by oxLDL was investigated by flow cytometry and Western blot. We also measured the production of reactive oxygen species (ROS) using the fluorescent probe 2',7'-dichlorofluorescein acetoxymethyl ester (DCF-AM). Furthermore, several apoptotic phenomena including increased cytosolic calcium, alteration of mitochondrial membrane potential, cytochrome c release and activation of caspase-3 were also investigated. Apoptotic cell death was characterized by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) stain. The results showed that honokiol prevented the copper-induced oxidative modification of LDL. Honokiol also ameliorated the oxLDL-diminished eNOS protein expression and reduced the oxLDL-induced adhesion molecules and the adherence of THP-1 cells to HUVECs. Furthermore, honokiol attenuated the oxLDL-induced cytotoxicity, apoptotic features, ROS generation, intracellular calcium accumulation and the subsequent mitochondrial membrane potential collapse, cytochrome c release and activation of caspase-3. Our results suggest that honokiol may have clinical implications in the prevention of atherosclerotic vascular disease.

Topics: Antioxidants; Apoptosis; Biphenyl Compounds; Calcium; Caspase 3; Caspases; Cell Adhesion; Cell Line; Cytochromes c; E-Selectin; Endothelial Cells; Humans; Intercellular Adhesion Molecule-1; Lignans; Lipoproteins, LDL; Membrane Potentials; Mitochondria; Nitric Oxide Synthase Type III; Reactive Oxygen Species; Vascular Cell Adhesion Molecule-1

The therapeutic goal in liver fibrosis is the reversal of fibrosis and the selective clearance of activated hepatic stellate cells (HSCs) by inducing apoptosis. Over the past several years, we have screened for natural products that mediate apoptosis in activated HSCs. Among the candidate compounds, honokiol, isolated from Magnoliae cortex, was found to induce apoptotic death in activated rat HSCs, while there was no cell viability change in hepatocytes, at concentrations of 12.5-50 microM. Apoptosis was identified by DNA fragmentation, activation of caspase-3 and -9, and the proteolytic cleavage of poly(ADP-ribose) polymerase, down-regulation of bcl-2 and the release of mitochondrial cytochrome c into the cytoplasm.

Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Biphenyl Compounds; Caspases; Cytochromes c; Dose-Response Relationship, Drug; Drugs, Chinese Herbal; Enzyme Activation; Flow Cytometry; Hepatocytes; Lignans; Magnolia; Male; Phytotherapy; Rats; Rats, Sprague-Dawley