Bee Venom Suppresses EGF-Induced Epithelial-Mesenchymal Transition and Tumor Invasion in Lung Cancer Cells.

Bee venom of Apis mellifera is a traditional medicine in Asia. It has been used with promoting results for the treatment of pain, rheumatoid, and cancer disease. The purpose of this study was to investigate the effects of bee venom on epidermal growth factor (EGF)-induced epithelial-mesenchymal transition (EMT) in non-small cell lung cancer (NSCLC) and determine possible signaling pathway affected in EGF-induced EMT in A549 cells. Bee venom inhibited EGF-induced F-actin reorganization and cell invasion, and suppressed EGF-induced EMT, processes associated with tumor metastasis in NSCLC. Bee venom enhanced the upregulation of E-cadherin and the downregulation of vimentin and inhibited EGF-induced ERK, JNK, FAK, and mTOR phosphorylation in A549 cells. However, the inhibition of JNK phosphorylation by bee venom was not related to the inhibitory effects of EMT. Furthermore, we found that bee venom suppressed the EMT-related transcription factors ZEB2 and Slug by blocking EGF-induced ERK, FAK and mTOR phosphorylation. Bee venom inhibits EGF-induced EMT by blocking the phosphorylation of ERK, FAK, and mTOR, resulting in the suppression of ZEB2 and Slug. These data suggest bee venom as a potential antimetastatic agent for NSCLC.

Anti-Proliferative and Pro-Apoptotic Effects of Licochalcone A through ROS-Mediated Cell Cycle Arrest and Apoptosis in Human Bladder Cancer Cells.

Licochalcone A (LCA) is a chalcone that is predominantly found in the root of Glycyrrhiza species, which is widely used as an herbal medicine. Although previous studies have reported that LCA has a wide range of pharmacological effects, evidence for the underlying molecular mechanism of its anti-cancer efficacy is still lacking. In this study, we investigated the anti-proliferative effect of LCA on human bladder cancer cells, and found that LCA induced cell cycle arrest at G2/M phase and apoptotic cell death. Our data showed that LCA inhibited the expression of cyclin A, cyclin B1, and Wee1, but increased the expression of cyclin-dependent kinase (Cdk) inhibitor p21WAF1/CIP1, and increased p21 was bound to Cdc2 and Cdk2. LCA activated caspase-8 and -9, which are involved in the initiation of extrinsic and intrinsic apoptosis pathways, respectively, and also increased caspase-3 activity, a typical effect caspase, subsequently leading to poly (ADP-ribose) polymerase cleavage. Additionally, LCA increased the Bax/Bcl-2 ratio, and reduced the integrity of mitochondria, which contributed to the discharge of cytochrome c from the mitochondria to the cytoplasm. Moreover, LCA enhanced the intracellular levels of reactive oxygen species (ROS); however, the interruption of ROS generation using ROS scavenger led to escape from LCA-mediated G2/M arrest and apoptosis. Collectively, the present data indicate that LCA can inhibit the proliferation of human bladder cancer cells by inducing ROS-dependent G2/M phase arrest and apoptosis.

Ascochlorin induces caspase-independent necroptosis in LPS-stimulated RAW 264.7 macrophages.

ETHNOPHARMACOLOGICAL RELEVANCE: Plant-specific fungus of natural compound of Ascochyta viciae has traditionally been used in the treatment of sleeping sickness and tumors. The anti-tumor activities of the compounds obtained from Pisum sativum L were evaluated in this study. AIM OF THE STUDY: In this study, during the prolonged incubation, treatment of the LPS-stimulated tumor-like macrophage RAW 264.7 cells with ASC exhibited the shift of anti-inflammatory behavior to a type of necroptotic cell death named necroptosis. MATERIALS AND METHODS: Ascochlorin (ASC) purified from plant-specific fungus Ascochyta viciae is a natural compound with the trimethyl oxocyclohexyl structure and an anti-cancer and antibiotic agent. The fungus contributes to the Ascochyta blight disease complex of pea (Pisum sativum L). RAW 264.7 cells have been stimulated with LPS and treated with ASC. Cell viability of the LPS-treated RAW 264.7 cells and bone marrow-derived macrophage (BMDM) cells were examined. Flow cytometry analysis with 7AAD and Annexin V was examined for the apoptotic or necroptosis/late-apoptosis. Cleaved caspase-3, -7 and -8 as well as cleaved PARP were assessed with a caspase inhibitor, z-VAD-fmk. LPS-responsible human leukemic U937 and colon cancer SW480 and HT-29 cells were also examined for the cell viabilities. RESULTS: Flow cytometry analysis after Annexin V and 7AAD double staining showed that ASC alone induces apoptosis in RAW 264.7 cells, while it induces necroptosis/late-apoptosis in LPS-treated RAW 264.7 cells. 7AAD and Annexin V positive populations were increased in the LPS-treated cells with ASC. Although viability of LPS-treated cells with ASC was decreased, the amounts of cleaved caspase-3, -7 and -8 as well as cleaved PARP were reduced when compared with ASC-treated cells. Upon ASC treatment, the cleaved caspase-8 level was not changed, however, cleaved caspase-3, -7, and PARP were reduced in LPS-stimulated RAW 264.7 cells treated with ASC, claiming a caspase-8 independent necroptosis of ASC. Furthermore, ASC and LPS-cotreated cells which a caspase inhibitor, z-VAD-fmk, was pretreated, showed the decreased cell viability compared with control cells without the inhibitor. Cell viability of RAW 264.7 cells co-treated with ASC and LPS when treated with z-VAD was decreased. In the LPS-responsible human leukemic U937 and colon cancer SW480 and HT-29 cells, cell viabilities were decreased by 10 µM ASC. CONCLUSION: Prolonged stimulation of ASC with LPS induces the necroptosis in RAW cells. Activated immune cells may share the susceptibility of antitumor agents with the cancer cells.

Morin enhances auranofin anticancer activity by up-regulation of DR4 and DR5 and modulation of Bcl-2 through reactive oxygen species generation in Hep3B human hepatocellular carcinoma cells.

Evidence suggests that auranofin (AF) exhibits anticancer activity by inhibiting thioredoxin reductase (TrxR). Here, in this study, we have investigated the synergistic effects of AF and morin and their mechanism for the anticancer effects focusing on apoptosis in Hep3B human hepatocellular carcinoma cells. We assessed the anticancer activities by annexin V/PI double staining, caspase, and TrxR activity assay. Morin enhances the inhibitory effects on TrxR activity of AF as well as reducing cell viability. Annexin V/PI double staining revealed that morin/AF cotreatment induced apoptotic cell death. Morin enhances AF-induced mitochondrial membrane potential (ΔΨm) loss and cytochrome c release. Further, morin/AF cotreatment upregulated death receptor DR4/DR5, modulated Bcl-2 family members (upregulation of Bax and downregulation of Bcl-2), and activated caspase-3, -8, and -9. Morin also enhances AF-induced reactive oxygen species (ROS) generation. The anticancer effects results from caspase-dependent apoptosis, which was triggered via extrinsic pathway by upregulating TRAIL receptors (DR4/DR5) and enhanced via intrinsic pathway by modulating Bcl-2 and inhibitor of apoptosis protein family members. These are related to ROS generation. In conclusion, this study provides evidence that morin can enhance the anticancer activity of AF in Hep3B human hepatocellular carcinoma cells, indicating that its combination could be an alternative treatment strategy for the hepatocellular carcinoma.

Esculentoside B inhibits inflammatory response through JNK and downstream NF-κB signaling pathway in LPS-triggered murine macrophage RAW 264.7 cells.

Natural compound esculentoside B (EsB), (2S,4aR,6aR,6aS,6bR,8aR,9R,10R,11S,12aR,14bS)-11-hydroxy-9-(hydroxymethyl)-2 methoxycarbonyl-2,6a,6b,9,12a-pentamethyl-10-[(2S,3R,4S,5R)-3,4,5-trihydroxyoxan-2-yl]oxy-1,3,4,5,6,6a,7,8,8a,10,11,12,13,14b-tetradecahydropicene-4a-carboxylic acid with molecular weight of 664.833, isolated from roots of Phytolacca acinosa Roxb has been widely used as a constituent of traditional Chinese medicine (TCM). However, the anti-inflammatory capacity of EsB has not been reported yet. Therefore, the objective of this study was to investigate anti-inflammatory activities of EsB in LPS-treated macrophage RAW 264.7 cells. EsB could inhibit nitric oxide (NO) production. EsB also suppressed gene and protein expression levels of inducible isoform of NO synthase (NOS) and cyclooxygenase-2 in a dose-dependent manner. In addition, EsB decreased gene expression and protein secretion levels of pro-inflammatory cytokines such as IL-1ß, TNF-α, and IL-6. EsB remarkably suppressed nuclear translocation of nuclear factor kappa-B (NF-κB) from cytosolic space. Phosphorylation of IκB was also inhibited by EsB. Moreover, EsB specifically down-regulated phospho-c-Jun N-terminal kinase (p-JNK), but not p-p38 or phospho-extracellular signal-regulated kinase 1/2 (p-ERK1/2). Taken together, these results suggest that EsB has inhibitory effect on inflammatory response by inactivating NF-κB and p-JNK. It could be used as a new modulatory drug for effective treatment of inflammation-related diseases.

Oldenlandia diffusa suppresses metastatic potential through inhibiting matrix metalloproteinase-9 and intercellular adhesion molecule-1 expression via p38 and ERK1/2 MAPK pathways and induces apoptosis in human breast cancer MCF-7 cells.

ETHNOPHARMACOLOGY RELEVANCE: Oldenlandia diffusa (OD) has long been known as an apoptotic inducer in breast tumors in ethnomedicine. AIM OF THE STUDY: To scientifically confirm the anti-breast cancer effects of water, methanol (MeOH) and butanol (BuOH) extracts of O. diffusa on cell apoptosis, matrix metalloproteinases (MMPs), intercellular adhesion molecule (ICAM)-1 and intracellular signaling in MCF-7 breast cancer cells. MATERIALS AND METHODS: MeOH extracts (MOD) and BuOH extracts (BOD) were prepared and examined for their ability to inhibit phorbol myristate acetate (PMA)-induced matrix metalloproteinase (MMP)-9 and intercellular adhesion molecule (ICAM)-1 expressions in MCF-7 human breast cancer cells. Additionally, transwell migration, invasion and transcriptional activity were assessed. Results of immunofluorescence confocal microscopy for translocation of NF-κB and p-ERK and p-p38 were also checked. Finally, apoptotic signals including processed caspase-8, caspase-7, poly ADP-ribose polymerase, Bax and Bcl-2 were examined. RESULTS: MOD and BOD specifically inhibited PMA-induced MMP-9 expression as well as invasive and migration potential via ICAM-1. The inhibitory activity was also based on the suppressed transcriptional activity in MCF-7 breast cancer cells. Results of immunofluorescence confocal microscopy showed that translocation of NF-κB decreased upon BOD and MOD treatments, with a decreased level of p-ERK and p-p38 phosphorylation. In addition, treatment of MCF-7 cells with MOD and BOD activated apoptosis-linked proteins including enzymatically active forms of processed caspase-8, caspase-7 and poly ADP-ribose polymerase, together with increased expression of mitochondrial apoptotic protein, Bax and decreased expression of Bcl-2. CONCLUSION: The results indicate that OD as an anti-metastatic agent suppresses the metastatic response by targeting p-ERK, p-38 and NF-κB, thus reducing the invasion capacity of MCF-7 breast cancer cells through inhibition of MMP-9 and ICAM-1 expression and plays an important role in the regulation of breast cancer cell apoptosis.

An exploration of the antioxidant effects of garlic saponins in mouse-derived C2C12 myoblasts.

In this study, we aimed to confirm the protective effects of garlic saponins against oxidative stress-induced cellular damage and to further elucidate the underlying mechanisms in mouse-derived C2C12 myoblasts. Relative cell viability was determined by 3-(4.5-dimethylthiazol-2-yl)-2.5 diphenyltetrazolium bromide assay. Comet assay was used to measure DNA damage and oxidative stress was determined using 2',7'-dichlorofluorescein diacetate to measure intracellular reactive oxygen species (ROS) generation. Western blot analysis and small interfering RNA (siRNA)-based knockdown were used in order to investigate the possible molecular mechanisms. Our results revealed that garlic saponins prevented hydrogen peroxide (H2O2)-induced growth inhibition and exhibited scavenging activity against intracellular ROS. We also observed that garlic saponins prevented H2O2-induced comet tail formation and decreased the phosphorylation levels of γH2AX expression, suggesting that they can prevent H2O2-induced DNA damage. In addition, garlic saponins increased the levels of heme oxygenase-1 (HO-1), a potent antioxidant enzyme associated with the induction and phosphorylation of nuclear factor erythroid 2-related factor 2 (Nrf2) and the translocation of Nrf2 from the cytosol into the nucleus. However, the protective effects of garlic saponins on H2O2-induced ROS generation and growth inhibition were significantly reduced by zinc protoporphyrin Ⅸ, an HO-1 competitive inhibitor. In addition, the potential of garlic saponins to mediate HO-1 induction and protect against H2O2­mediated growth inhibition was adversely affected by transient transfection with Nrf2-specific siRNA. Garlic saponins activated extracellular signal­regulated kinase (ERK) signaling, whereas a specific ERK inhibitor was able to inhibit HO-1 upregulation, as well as Nrf2 induction and phosphorylation. Taken together, the findings of our study suggest that garlic saponins activate the Nrf2/HO-1 pathway by enabling ERK to contribute to the induction of phase Ⅱ antioxidant and detoxifying enzymes, including HO-1 in C2C12 cells.

Anti-inflammatory potential of saponins derived from cultured wild ginseng roots in lipopolysaccharide-stimulated RAW 264.7 macrophages.

Ginseng, namely the root of Panax ginseng Meyer, is a well-known traditional medicine that has been used in Asian countries for thousands of years. Ginseng saponins have been shown to exert a variety of prominent pharmacological effects in a number of diseases. The aim of the present study was to identify the anti-inflammatory effects of total saponins extracted from cultured wild ginseng roots (TSWG) on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. An elevated production of nitric oxide (NO) was detected in the RAW 264.7 cells in response to stimulation with LPS, as shown by NO detection assay using Griess reagent. However, pre-treatment with TSWG inhibited the production of NO through the suppression of inducible NO synthase gene expression. Furthermore, the LPS-induced gene expression and production of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) were significantly reduced by treatment with TSWG, as shown by ELISA, and western blot analysis and RT-PCR, respectively. In the LPS-stimulated RAW 264.7 cells, nuclear factor-κB (NF-κB) was translocated from the cytosol to the nucleus, while pre-treatment with TSWG induced the sequestration of NF-κB in the cytosol through the inhibition of the inhibitor of κB degradation, as shown by immunofluorescence staining. TSWG also contributed to the downregulation of mitogen-activated protein kinases and Akt in the LPS-stimulated RAW 264.7 cells. Additionally, in the TSWG-treated RAW 264.7 cells, we observed the activation of nuclear factor (erythroid-derived 2)-like 2 and an increase in heme oxygenase-1 expression; these effects were associated with the inhibition of the generation of reactive oxygen species. The results from the present study indicate that TSWG exerts anti-inflammatory and antioxidant effects, suggesting that TSWG may be an effective therapeutic agent for inflammatory diseases and prevent cellular damage induced by oxidative stress.

Melittin has a chondroprotective effect by inhibiting MMP-1 and MMP-8 expressions via blocking NF-κB and AP-1 signaling pathway in chondrocytes.

Bee venom is a natural ingredient produced by the honey bee (Apis mellifera), and has been widely used in China, Korea and Japan as a traditional medicine for various diseases such as arthritis, rheumatism, and skin diseases However, the regulation of the underlying molecular mechanisms of the anti-arthritis by bee venom and its major peptides is largely unknown. In this study, we investigated the potential molecular mechanisms underlying the anti-arthritis effect of bee venom and its major peptides, melittin and apamin, in tumor necrosis factor-α (TNF-α) responsive C57BL/6 mice chondrocyte cells. The bee venom and melittin significantly and selectively suppressed the TNF-α-mediated decrease of type II collagen expression, whereas the apamin had no effects on the type II collagen expression. We, furthermore, found that the bee venom and melittin inhibited the protein expression of matrix metalloproteinase (MMP)-1 and MMP-8, which suggests that the chondroprotective effect of bee venom may be caused by melittin. The inhibitory effects of melittin on the TNF-α-induced MMP-1 and MMP-8 protein expression were regulated by the inhibition of NF-kB and AP-1. In addition, melittin suppressed the TNF-α-induced phosphorylation of Akt, JNK and ERK1/2, but did not affect the phosphorylation of p38 kinase. These results suggest that melittin suppresses TNF-α-stimulated decrease of type II collagen expression by the inhibiting MMP-1 and MMP-8 through regulation of the NF-kB and AP-1 pathway and provision of a novel role for melittin in anti-arthritis action.

Melittin inhibits TGF-ß-induced pro-fibrotic gene expression through the suppression of the TGFßRII-Smad, ERK1/2 and JNK-mediated signaling pathway.

Renal fibrosis is characterized by the excessive accumulation of extracellular matrix (ECM) proteins such as type I collagen, fibronectin, and by the increased expression of PAI-1. This study evaluated the anti-fibrotic effect of bee venom and its major compounds (melittin and apamin) on TGF-ß-induced pro-fibrotic gene expression. Bee venom and melittin significantly suppressed type I collagen, fibronectin, and PAI-1 protein expression in the TGF-ß-treated kidney fibroblast. However, apamin only inhibited the expression of fibronectin and type I collagen. These results indicated that the inhibitory effects of bee venom on TGF-ß-induced pro-fibrotic gene expression are caused by melittin. Moreover, we attempted to elucidate mechanisms underlying the anti-fibrotic effect of melittin. Melittin dramatically inhibited the phosphorylation of TGFßRII and Smad2/3. Also, melittin inhibited the phosphorylation of ERK1/2 and JNK, but not the phosphorylation of PI3K, Akt, and p38. These results suggested that melittin inhibits TGF-ß-induced pro-fibrotic genes expression through the suppression of TGFßR-Smad2/3, ERK1/2, and JNK phosphorylation, and melittin can be used as a clinical drug for the treatment of fibrosis associated with renal diseases.

Neuroprotective effects of melittin on hydrogen peroxide-induced apoptotic cell death in neuroblastoma SH-SY5Y cells.

BACKGROUND: Free radicals are involved in neuronal cell death in human neurodegenerative diseases. Since ancient times, honeybee venom has been used in a complementary medicine to treat various diseases and neurologic disorders. Melittin, the main component of honeybee venom, has various biologic effects, including anti-bacterial, anti-viral, and anti-inflammatory activities. METHODS: We investigated the neuroprotective effects of melittin against H2O2-induced apoptosis in the human neuroblastoma cell line SH-SY5Y. The neuroprotective effects of melittin on H2O2-induced apoptosis were investigated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylterazolium bromide assay, caspase 3 activity, 4,6-diamidino-2-phenylindole staining, a lactate dehydrogenase release assay, Western blots, and reverse transcription-polymerase chain reaction. RESULTS: The H2O2-treated cells had decreased cell viability with apoptotic features and increased production of caspase-3. On the other hand, melittin treatment increased cell viability and decreased apoptotic DNA fragmentation. Melittin attenuated the H2O2-induced decrease in mRNA and protein production of the anti-apoptotic factor Bcl-2. In addition, melittin inhibited both the H2O2-induced mRNA and protein expression of Bax-associated pro-apoptotic factor and caspase-3. CONCLUSIONS: These findings suggest that melittin has potential therapeutic effects as an agent for the prevention of neurodegenerative diseases.

N-benzyl-N-methyldecan-1-amine, a phenylamine derivative isolated from garlic cloves, induces G2/M phase arrest and apoptosis in U937 human leukemia cells.

Epidemiological studies indicate that components of garlic (Allium sativum) have anti-proliferative effects against various types of cancer. In the present study, we investigated the effect of newly isolated phenylamine derivative N-benzyl-N-methyldecan-1-amine (NBNMA) from garlic cloves on the inhibition of the growth and apoptosis of human leukemia U937 cells and its potential anticancer mechanism. NBNMA exhibited an antiproliferative effect in U937 cells by inducing cell cycle arrest at the G2/M phase and apoptotic cell death. Western blot analyses revealed that NBNMA decreased the expression of the regulator genes of G2/M phase progression, cyclin dependent kinase (Cdk) 2 and Cdc2 and elevated the expression of the Cdk inhibitor p21WAF1/CIP1 in a p53-independent manner. In addition, NBNMA activated caspase-8 and caspase-9, initiator caspases of the extrinsic and intrinsic pathways of apoptosis, respectively, which led to activation of executioner caspase-3 along with degradation of poly(ADP-ribose) polymerase. NBNMA-induced apoptosis was observed in parallel with an increased ratio of pro-apoptotic Bax and Bad/anti-apoptotic Bcl-2 and Bcl-xL, and inhibition of inhibitor of apoptosis protein (IAP) family members XIAP and cIAP-1. Furthermore, NBNMA-treated cells displayed enhanced release of cytochrome c from the mitochondria into the cytosol concomitant with a loss of mitochondrial membrane potential and downregulation of Bid, suggesting that NBNMA-induced apoptosis occurred via the extrinsic and intrinsic apoptotic pathways with a possible link to Bid protein activity between the two pathways. These results indicate that NBNMA has promising potential to become a novel anticancer agent for the treatment of leukemia. We provide new insight into the mechanisms underlying the anticancer effect of NBNMA.

Moringa fruit inhibits LPS-induced NO/iNOS expression through suppressing the NF-κ B activation in RAW264.7 cells.

In this study, we evaluated the anti-inflammatory effects of moringa (Moringa oleifera Lam.), a natural biologically active substance, by determining its inhibitory effects on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated macrophage RAW264.7 cells. Extracts from different parts of moringa (root, leaf, and fruit) reduced LPS-induced nitric oxide (NO) release in a dose-dependent manner. The moringa fruit extract most effectively inhibited LPS-induced NO production and levels of inducible nitric oxide synthase (iNOS). The moringa fruit extract also was shown to suppress the production of inflammatory cytokines including IL-1ß, TNF-α, and IL-6. Furthermore, moringa fruit extract inhibited the cytoplasmic degradation of I κ B -α and the nuclear translocation of p65 proteins, resulting in lower levels of NF -κ B transactivation. Collectively, the results of this study demonstrate that moringa fruit extract reduces the levels of pro-inflammatory mediators including NO , IL-1ß, TNF-α, and IL-6 via the inhibition of NF -κ B activation in RAW264.7 cells. These findings reveal, in part, the molecular basis underlying the anti-inflammatory properties of moringa fruit extract.

Oleifolioside B-mediated autophagy promotes apoptosis in A549 human non-small cell lung cancer cells.

The biochemical mechanisms of cell death by oleifolioside B (OB), a cycloartane-type triterpene glycoside isolated from Dendropanax morbifera Leveille, were investigated in A549 human lung carcinoma cells. Our data indicated that exposure to OB led to caspase activation and typical features of apoptosis; however, apoptotic cell death was not prevented by z-VAD-fmk, a pan-caspase inhibitor, demonstrating that OB-induced apoptosis was independent of caspase activation. Subsequently, we found that OB increased autophagy, as indicated by an increase in monodansylcadaverine fluorescent dye-labeled autophagosome formation and in the levels of the autophagic form of microtubule-associated protein 1 light chain 3 and Atg3, an autophagy-specific gene, which is associated with inhibiting phospho-nuclear factor erythroid 2-related factor 2 (Nrf2) expression. However, pretreatment with bafilomycin A1, an autophagy inhibitor, attenuated OB-induced apoptosis and dephosphorylation of Nrf2. The data suggest that OB-induced autophagy functions as a death mechanism in A549 cells and OB has potential as a novel anticancer agent capable of targeting apoptotic and autophagic cell death and the Nrf2 signaling pathway.

Tanshinone IIA improves endoplasmic reticulum stress-induced insulin resistance through AMP-activated protein kinase.

The aim of the present study was to determine the effect of Tanshinone IIA (Tan IIA) on endoplasmic reticulum (ER) stress-induced insulin resistance in L6 myotubes and db/db mice. ER stress markers, RNA-activated protein kinase-like ER resident kinase (PERK), JNK, and AMPK activity were determined in tunicamycin-treated L6 myotubes. Insulin resistance was monitored using glucose uptake assays in vitro and blood glucose levels in vivo. Tan IIA clearly suppressed the phosphorylations of PERK and JNK and potentiated insulin-mediated Akt phosphorylation as well as glucose uptake via AMPK activation under ER stress. Furthermore, these effects are completely abrogated by siRNA-mediated knockdown of AMPK or LKB1. In addition, Tan IIA reduced blood glucose levels and body weights in db/db mice without altering food intake. These findings suggest that Tan IIA enhances insulin sensitivity and improves glucose metabolic disorders by increasing AMPK activity and attenuating ER stress-induced insulin resistance.

Manassantin A isolated from Saururus chinensis inhibits 5-lipoxygenase-dependent leukotriene C4 generation by blocking mitogen-activated protein kinase activation in mast cells.

In this study, manassantin A (Man A), an herbal medicine isolated from Saururus chinensis (S. chinensis), markedly inhibited 5-lipoxygenase (5-LO)-dependent leukotriene C(4) (LTC(4)) generation in bone marrow-derived mast cells (BMMCs) in a concentration-dependent manner. To investigate the molecular mechanisms underlying the inhibition of LTC(4) generation by Man A, we assessed the effects of Man A on phosphorylation of cytosolic phospholipase A(2) (cPLA(2)) and mitogen-activated protein kinases (MAPKs). Inhibition of LTC(4) generation by Man A was accompanied by a decrease in cPLA(2) phosphorylation, which occurred via the MAPKs including extracellular signal-regulated protein kinase-1/2 (ERK1/2) as well as p38 and c-Jun N-terminal kinase (JNK) pathways. Taken together, the present study suggests the Man A represents a potential therapeutic approach for the treatment of airway allergic-inflammatory diseases.

Saucerneol G, a new lignan, from Saururus chinensis inhibits matrix metalloproteinase-9 induction via a nuclear factor κB and mitogen activated protein kinases in lipopolysaccharide-stimulated RAW264.7 cells.

This study was conducted to demonstrate the inhibitory effect of saucerneol G (SG), a new lignan, isolated from the aerial part of Saururus chinensis (Saururaceae) on lipopolysaccharide (LPS)-stimulated matrix metalloproteinase-9 (MMP)-9 inductions in RAW 264.7 cells. Aimed at evaluating the mechanism of action by which SG inhibits the LPS-mediated induction of MMP-9, the effects of SG on nuclear factor-κB (NF-κB) DNA binding activity, NF-κB-dependent reporter gene activity, inhibitory factor-κB (IκB) phosphorylation, degradation and p65 nuclear translocation were assessed. SG profoundly suppressed the DNA binding activity and the reporter gene activity as well as translocation of NF-κB p65 subunit. Furthermore, SG also dose dependently inhibited LPS-stimulated activation of mitogen-activated protein kinases (MAPKs). These findings suggest that SG may inhibit LPS-stimulated MMP-9 induction by blocking NF-κB and MAPKs activation.

Bee venom reduces atherosclerotic lesion formation via anti-inflammatory mechanism.

The components of bee venom (BV) utilized in the current study were carefully scrutinized with chromatography. Despite its well documented anti-inflammatory property, there are no reports regarding the influence of BV on the expression of cellular adhesion molecules in the vascular endothelium. A great amount of information exists concerning the effects of an atherogenic diet on atherosclerotic changes in the aorta, but little is known about the molecular mechanisms and the levels of gene regulation involved in the anti-inflammatory process induced by BV. The experimental atherosclerosis was induced in mice by a lipopolysaccharide (LPS) injection and an atherogenic diet. The animals were divided into three groups, the NC groups of animals that were fed with a normal diet, the LPS/fat group was fed with the atherogenic diet and received intraperitoneal injections of LPS, and the LPS/fat + BV group was given LPS, an atherogenic diet and intraperitoneal BV injections. At the end of each treatment period, the LPS/fat + BV group had decreased levels of total cholesterol (TC) and triglyceride (TG) in their serum, compared to the LPS/fat group. The LPS/fat group had significant expression of tumor necrosis factor (TNF)-α and interleukin (IL)-1ß in the serum, compared with the NC group (p < 0.05). The amount of cytokines reduced consistently in the BV treatment groups compared with those in LPS/fat group. BV significantly reduced the amount of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), transforming growth factor-ß1 (TGF-ß1) and fibronectin in the aorta, compared with the LPS/fat group (p < 0.05). A similar pattern was also observed in the heart. In conclusion, BV has anti-atherogenic properties via its lipid-lowering and anti-inflammatory mechanisms.

Bee venom inhibits hepatic fibrosis through suppression of pro-fibrogenic cytokine expression.

Bee venom (BV) has a long tradition of use for the control of pain and inflammation in various chronic diseases. Carbon tetrachloride (CCl4) is known to induce hepatotoxicity after being metabolized to the highly reactive trichloromethyl free radical and its peroxy radical. The purpose of the current study was to examine whether BV regulates the pro-inflammation and fibrosis related genes against a mouse model of hepatic fibrosis induced by CCl4 and ethanol-treated hepatocytes (ETH). Test mice were administered with CCl4 (2 ml/mg) and hepatocytes were treated with 25 mM ethanol. BV was added to the final concentration of 0.05-0.5 mg/kg and 1-100 ng/ml for in vivo and in vitro testing, respectively. Fibrotic livers and ETH were used for the measurement of hepatocyte necrosis, pro-inflammatory cytokines and fibrogenic genes. BV suppressed CCl4-induced hepatocyte necrosis markers of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT). It also inhibited the secretion of interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha. Moreover, BV inhibited CCl4-induced expression of transforming growth factor (TGF)-beta1, alpha-smooth muscle actin (SMA) and fibronectin. Similarly, ETH exhibited significant suppression of IL-1beta, TNF-alpha, TGF-beta1 and fibronectin when cultured with BV. These results suggest that BV possesses anti-fibrogenic properties that are mediated by the suppression of pro-inflammatory cytokines and fibrogenic gene expression. BV has substantial therapeutic potential for the treatment of fibrotic diseases.