Apoptotic Effect of Sanggenol L via Caspase Activation and Inhibition of NF‐κB Signaling in Ovarian Cancer Cells

In the present study, the underlying apoptotic mechanism of sanggenol L was elucidated in ovarian cancer cells. Sanggenol L showed cytotoxic and antiproliferative effect in A2780, SKOV‐3, and OVCAR‐3 ovarian cancer cells in a concentration‐dependent fashion. Consistently, sanggenol L increased sub‐G1 phase population and early and late apoptotic portion in ovarian cancer cells. Also, sanggenol L activated caspase9/3, suppressed the phosphorylation of IκBα and p65 NF‐κB (nuclear factor kappa‐light‐chain‐enhancer of activated B cells), attenuated the expression of Cyclin D1, and cleaved poly(adenosine diphosphate ribose ‐ribose) polymerase in SKOV‐3, A2780, and OVCAR‐3 cells. Furthermore, sanggenol L blocked nuclear translocation of NF‐κB and also attenuated the expression of NF‐κB related genes such as c‐Myc, Cyclin D1, and Bcl‐_XL, Bcl‐2, in lipopolysaccharide‐treated SKOV‐3 cells. Overall, our findings for the first time suggest that sanggenol L induces apoptosis via caspase activation and inhibition of NF‐κB/IκBα phosphorylation as a potent chemotherapeutic agent for ovarian cancers. Copyright © 2015 John Wiley & Sons, Ltd.     

Apigenin as an anticancer agent

Apigenin is an edible plant‐derived flavonoid that has been reported as an anticancer agent in several experimental and biological studies. It exhibits cell growth arrest and apoptosis in different types of tumors such as breast, lung, liver, skin, blood, colon, prostate, pancreatic, cervical, oral, and stomach, by modulating several signaling pathways. Apigenin induces apoptosis by the activation of extrinsic caspase‐dependent pathway by upregulating the mRNA expressions of caspase‐3, caspase‐8, and TNF‐α. It induces intrinsic apoptosis pathway as evidenced by the induction of cytochrome c, Bax, and caspase‐3, while caspase‐8, TNF‐α, and B‐cell lymphoma 2 levels remained unchanged in human prostate cancer PC‐3 cells. Apigenin treatment leads to significant downregulation of matrix metallopeptidases‐2, ?9, Snail, and Slug, suppressing invasion. The expressions of NF‐κB p105/p50, PI3K, Akt, and the phosphorylation of p‐Akt decreases after treatment with apigenin. However, apigenin‐mediated treatment significantly reduces pluripotency marker Oct3/4 protein expression which might be associated with the downregulation of PI3K/Akt/NF‐κB signaling.     

Diosmetin exhibits anti‐proliferative and anti‐inflammatory effects on TNF‐α‐stimulated human rheumatoid arthritis fibroblast‐like synoviocytes through regulating the Akt and NF‐κB signaling pathways

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by inflammation and proliferation of synovial tissues. Diosmetin is a bioflavonoid possessing an anti‐inflammatory property. Herein, we aimed to study the effects of diosmetin on the inflammation and proliferation of RA fibroblast‐like synoviocytes MH7A cells. MH7A cell proliferation was measured using cell counting kit‐8 assay. Cell apoptosis was examined using flow cytometry. The production of inflammatory cytokines including interleukin (IL)‐1β, IL‐6, IL‐8, and matrix metalloproteinase‐1 (MMP‐1) was measured using enzyme‐linked immunosorbent assay (ELISA). Results showed that diosmetin inhibited tumor necrosis factor‐α (TNF‐α)‐induced proliferation increase in MH7A cells in a dose‐dependent manner. Diosmetin treatment resulted in an increase in apoptotic rates and a reduction in TNF‐α‐induced production of IL‐1β, IL‐6, IL‐8, and MMP‐1 in MH7A cells. Furthermore, diosmetin inhibited TNF‐α‐induced activation of protein kinase B (Akt) and nuclear factor‐κB (NF‐κB) pathways in MH7A cells. Suppression of Akt or NF‐κB promoted apoptosis and inhibited TNF‐α‐induced proliferation increase and production of IL‐1β, IL‐6, IL‐8, and MMP‐1 in MH7A cells, and diosmetin treatment enhanced these effects. Taken together, these findings suggested that diosmetin exhibited anti‐proliferative and anti‐inflammatory effects via inhibiting the Akt and NF‐κB pathways in MH7A cells.     

Isoforskolin and forskolin attenuate lipopolysaccharide‐induced inflammation through TLR4/MyD88/NF‐κB cascades in human mononuclear leukocytes

The principal active component of isoforskolin (ISOF) is from the plant Coleus forskohlii, native to China, which has attracted much attention for its biological effects. We hypothesize that ISOF and forskolin (FSK) pretreatment attenuates inflammation induced by lipopolysaccharide (LPS) related to toll‐like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and nuclear factor kappa B (NF‐κB) signaling. Mononuclear leukocytes (MLs) from healthy donors' blood samples were separated by using density gradient centrifugation. Protein levels of TLR4, MyD88, and NF‐κB were detected using western blot and inflammatory cytokines interleukin (IL) 1β, IL‐2, IL‐6, IL‐21, IL‐23, tumor necrosis factor (TNF) α, and TNF‐β were tested by enzyme‐linked immunosorbent assay and Quantibody array in MLs. Our results showed that LPS augmented the protein levels of TLR4, MyD88, and NF‐κB in MLs and the production of IL‐1β, IL‐2, IL‐6, IL‐21, IL‐23, TNF‐α, and TNF‐β in supernatants of MLs. Despite treatment with ISOF and FSK prior to LPS, the protein levels of TLR4, MyD88, NF‐κB, IL‐1β, IL‐2, IL‐6, IL‐21, IL‐23, TNF‐α, and TNF‐β in MLs were apparently decreased. roflumilast (RF) and dexamethasone (DM) had a similar effect on MLs with ISOF and FSK. Our results, for the first time, have shown that ISOF and FSK attenuate inflammation in MLs induced by LPS through down‐regulating protein levels of IL‐1β and TNF‐α, in which TLR4/MyD88/NF‐κB signal pathway could be involved.     

Retracted: Baicalin relieves lipopolysaccharide‐evoked inflammatory injury through regulation of miR‐21 in H9c2 cells

Myocarditis is a common heart disease which lacks effective treatment till now. Baicalin possesses plenty of activities, including anti‐inflammation. In this investigation, we attempted to investigate the influences of Baicalin on Lipopolysaccharide (LPS)‐evoked H9c2 cells.Cells viability, apoptosis, and expressions of apoptosis‐associated proteins were, respectively, measured utilizing CCK‐8 assay, flow cytometry and western blot. The levels of IL‐6 and TNF‐α were detected through enzyme‐linked immunosorbent assay, western blot and qRT‐PCR. miR‐21 expression was detected through qRT‐PCR and was silenced using cell transfection. The expressions of NF‐κB and PDCD4/JNK pathways related proteins were measured through western blot. We found that LPS stimulation induced cell apoptosis and upregulation of IL‐6 and TNF‐α. Baicalin treatment effectively suppressed LPS‐induced inflammation and apoptosis. The NF‐κB and PDCD4/JNK pathways were blocked by Baicalin. Additionally, the enhanced expression of miR‐21 triggered by LPS was further elevated by Baicalin. Further study revealed that the inhibiting effects of Baicalin on LPS‐evoked injury were largely attenuated by knockdown of miR‐21. Moreover, the associated NF‐κB and JNK pathways, which were suppressed by Baicalin treatment, were then activated by knockdown of miR‐21. Our present study revealed that Baicalin alleviated LPS‐evoked inflammatory injury via suppressing the NF‐κB and PDCD4/JNK pathways through regulating miR‐21 expression.     

Inhibition of TNF‐α‐Induced MUC5AC Mucin Gene Expression and Production by Wogonin Through the Inactivation of NF‐κB Signaling in Airway Epithelial Cells

In this study, we investigated whether wogonin significantly affects MUC5AC mucin gene expression and production in human airway epithelial cells. Confluent NCI‐H292 cells were pretreated with wogonin for 30 min and then stimulated with tumor necrosis factor‐α (TNF‐α) for 24 h or the indicated periods. The MUC5AC mucin gene expression and mucin protein production were measured by RT‐PCR and ELISA, respectively. We found that incubation of NCI‐H292 cells with wogonin significantly inhibited mucin production and down‐regulated MUC5AC gene expression induced by TNF‐α in a dose‐dependent fashion. To elucidate the action mechanism of wogonin, effect of wogonin on TNF‐α‐induced NF‐κB signaling pathway was investigated by western blot analysis. Wogonin inhibited NF‐κB activation induced by TNF‐α. Inhibition of IKK by wogonin led to the suppression of IκB phosphorylation and degradation, p65 nuclear translocation and NF‐κB‐regulated gene expression. This, in turn, led to the down‐regulation of MUC5AC protein production in NCI‐H292 cells. Wogonin also inhibited the gene products involved in cell survival (Bcl‐2) and proliferation (cyclooxygenase‐2). These results suggest that wogonin inhibits the NF‐κB signaling pathway, which may explain its role in the inhibition of MUC5AC mucin gene expression and production. Copyright © 2013 John Wiley & Sons, Ltd.     

Kaempferitrin inhibits proliferation,induces apoptosis,and ameliorates inflammation in human rheumatoid arthritis fibroblast‐like synoviocytes

Rheumatoid arthritis (RA) is a complex chronic inflammatory disease that is associated with the aberrant activation of fibroblast‐like synoviocytes (FLS). Kaempferitrin is a natural flavonoid glycoside that possesses anti‐inflammatory bioactivity. However, the effect of kaempferitrin on RA has not yet been revealed. The aim of the present study was to investigate the effect of kaempferitrin on human RA‐FLS MH7A cell line. We found that kaempferitrin inhibited proliferation and induced apoptosis of MH7A cells. Kaempferitrin decreased the levels of interleukin (IL)‐1β, IL‐6, tumor necrosis factor (TNF)‐α, matrix metalloproteinase (MMP)‐1, and MMP‐3 in MH7A cells. Moreover, kaempferitrin blocked the activation of nuclear factor‐κB (NF‐κB) and protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathways. Furthermore, treatment with kaempferitrin decreased paw thickness and arthritis scores, and reduced the serum levels of IL‐1β, IL‐6, and TNF‐α in a collagen‐induced arthritis mouse model. In conclusion, kaempferitrin inhibited cell proliferation, induced cell apoptosis, and ameliorated inflammation of RA‐FLS by suppressing the NF‐κB and Akt/mTOR pathways.     

Praeruptorin a inhibits lipopolysaccharide‐induced inflammatory response in murine macrophages through inhibition of NF‐κB pathway activation

Praeruptorin A (PA) is a pyranocoumarin compound isolated from the dried root of Peucedanum praeruptorum Dunn (Umbelliferae). However, the antiinflammatory effect of PA has not been reported. The present study investigated the antiinflammatory effect of PA in lipopolysaccharide (LPS)‐stimulated RAW 264.7 macrophage cells. PA significantly inhibited the LPS‐induced production of nitric oxide (NO), interleukin‐1β (IL‐1β) and tumor necrosis factor‐α (TNF‐α). The mRNA and protein expressions of inducible nitric oxide synthase (iNOS), IL‐1β and TNF‐α were also suppressed by this compound. Further study showed that PA decreased the cytoplasmic loss of inhibitor κB‐α (IκB‐α) protein and inhibited the translocation of NF‐κB from cytoplasm to nucleus. Taken together, the results suggest that PA may exert antiinflammatory effects in vitro in LPS‐stimulated RAW 264.7 macrophages through inhibition of NF‐κB signal pathway activation. Copyright © 2010 John Wiley & Sons, Ltd.     

Pongapin and Karanjin,furanoflavanoids of Pongamia pinnata,induce G2/M arrest and apoptosis in cervical cancer cells by differential reactive oxygen species modulation,DNA damage,and nuclear factor kappa‐light‐chain‐enhancer of activated B cell signaling

In this study, the antitumor activity of two furanoflavanoid derivatives, Pongapin and Karanjin, was evaluated in comparison with Plumbagin, a plant‐derived polyphenol with proven antitumor activity. The compounds differentially inhibit the growth of different cancer cell lines (most effective on HeLa cells), with very low inhibitory effect on the growth of normal mouse embryonic fibroblast cell line. Pongapin like Plumbagin could significantly increase the intracellular reactive oxygen species (ROS) in the HeLa cells by stabilization of nuclear factor of kappa light polypeptide gene enhancer in B‐cells inhibitor (I‐κB) expression and reduction of nuclear factor kappa‐light‐chain‐enhancer of activated B cells (NF‐κB) expression. In contrast, Karanjin could decrease ROS level by inhibition of I‐κB degradation resulting restriction of NF‐κB nuclear translocation. Pongapin and Plumbagin significantly increased DNA damage‐induced p53 expression and p21 nuclear expression. However, Karanjin treatment showed low DNA damage with increased p53 expression. The compounds induced G2/M arrest and increase in SubG1 population, indicating induction of apoptosis. Apoptosis was further validated by acridine orange/ethidium bromide dual staining and terminal deoxynucleotidyl transferase dUTP nick‐end labeling assay in HeLa cells after treatment with the compounds. The compounds induced caspase‐dependent apoptosis through induction of Bax/Bcl‐2 ratio either through increased expression of Bax by Pongapin and Plumbagin or low expression of Bcl‐2 by Karanjin. Thus, Pongapin and Karanjin may be potential natural anticancer agents in the future, like Plumbagin.     

Nimbolide Inhibits Nuclear Factor‐КB Pathway in Intestinal Epithelial Cells and Macrophages and Alleviates Experimental Colitis in Mice

Nimbolide is a limonoid extracted from neem tree (Azadirachta indica) that has antiinflammatory properties. The effect of nimbolide on the nuclear factor‐kappa B (NF‐κB) pathway in intestinal epithelial cells (IECs), macrophages and in murine colitis models was investigated. The IEC COLO 205, the murine macrophage cell line RAW 264.7, and peritoneal macrophages from interleukin‐10‐deficient (IL‐10^?/?) mice were preconditioned with nimbolide and then stimulated with tumor necrosis factor‐α (TNF‐α) or lipopolysaccharide. Dextran sulfate sodium‐induced acute colitis model and chronic colitis model in IL‐10^?/? mice were used for in vivo experiments. Nimbolide significantly suppressed the expression of inflammatory cytokines (IL‐6, IL‐8, IL‐12, and TNF‐α) and inhibited the phosphorylation of IκBα and the DNA‐binding affinity of NF‐κB in IECs and macrophages. Nimbolide ameliorated weight loss, colon shortening, disease activity index score, and histologic scores in dextran sulfate sodium colitis. It also improved histopathologic scores in the chronic colitis of IL‐10^?/? mice. Staining for phosphorylated IκBα was significantly decreased in the colon tissue after treatment with nimbolide in both models. Nimbolide inhibits NF‐κB signaling in IECs and macrophages and ameliorates experimental colitis in mice. These results suggest nimbolide could be a potentially new treatment for inflammatory bowel disease. Copyright © 2016 John Wiley & Sons, Ltd.     

Myrislignan Attenuates Lipopolysaccharide‐induced Inflammation Reaction in Murine Macrophage Cells Through Inhibition of NF‐κB Signalling Pathway Activation

Myrislignan is a new kind of lignan isolated from Myristica fragrans Houtt. Its antiinflammatory effects have not yet been reported. In the present study, the antiinflammatory effects and the underlying mechanisms of myrislignan in lipopolysaccharide (LPS)‐induced inflammation in murine RAW 264.7 macrophage cells were investigated. Myrislignan significantly inhibited LPS‐induced production of nitric oxide (NO) in a dose‐dependent manner. It inhibited mRNA expression and release of interleukin‐6 (IL‐6) and tumour necrosis factor‐α (TNF‐α). This compound significantly inhibited mRNA and protein expressions of inducible NO synthase (iNOS) and cyclooxygenase‐2 (COX‐2) dose‐dependently in LPS‐stimulated macrophage cells. Further study showed that myrislignan decreased the cytoplasmic loss of inhibitor κB‐α (IκB‐α) protein and the translocation of NF‐κB from cytoplasm to the nucleus. Our results suggest that myrislignan may exert its antiinflammatory effects in LPS‐stimulated macrophages cells by inhibiting the NF‐κB signalling pathway activation. Copyright © 2012 John Wiley & Sons, Ltd.     

Chrysophanol attenuates airway inflammation and remodeling through nuclear factor‐kappa B signaling pathway in asthma

Chrysophanol (CHR), a purified active constituent extracted from Rheum palmatum L., possesses anti‐inflammatory activity. This study aimed to evaluate its effects on asthma‐associated airway inflammation and remodeling. BALB/c mice were sensitized and challenged by ovalbumin (OVA) and administrated with different doses of CHR. We found that CHR decreased OVA‐induced pulmonary inflammation: the levels of interleukin (IL)‐4, IL‐5, and IL‐13, tumor necrosis factor (TNF)‐α, and inducible nitric oxide synthase were downregulated. CHR also attenuated airway remodeling induced by OVA challenge—CHR inhibited pulmonary α‐smooth muscle actin expression. Moreover, both the nuclear translocation and activity of NF‐κB p65 were inhibited by CHR in the asthmatic lung. Enhanced autophagy was initiated in the lung by OVA challenge as evidenced by upregulated light chain 3 beta, autophagy‐related protein 5, and Beclin 1. CHR suppressed OVA‐induced alterations in these autophagy‐related molecules. In vitro, CHR (2 or 20 μM) was used to treat human pulmonary epithelial BEAS‐2B cells in the presence of 10 ng/ml recombinant TNF‐α. CHR not only exhibited the antiproliferation effect but also inhibited the activation of nuclear factor‐kappa B (NF‐kB) signaling pathway in TNF‐α‐treated BEAS‐2B cells. In conclusion, our study indicates that CHR has the potential to ameliorate asthma.     

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.     

Paeonol ameliorates monosodium urate‐induced arthritis in rats through inhibiting nuclear factor‐κB‐mediated proinflammatory cytokine production

Moutan Cortex has been widely used to treat various types of arthritis in traditional Chinese medicine. Paeonol is isolated as an active ingredient from Moutan Cortex. However, the effect and potential mechanism of paeonol on gouty arthritis have not been evaluated. In this study, rats were treated intragastrically with paeonol for consecutive 7 days. On Day 5, rats were intra‐articularly injected with monosodium urate (MSU) crystals in the ankle joints to induce MSU‐induced arthritis (MIA). Paw volume was detected at various time points. Gait score was measured at 24 hr after MSU crystal injection. Ankle joints were collected for evaluation of histological score and expression of proinflammatory cytokines using hematoxylin and eosin staining and immunohistochemistry staining, respectively. Nuclear level of nuclear factor (NF)‐κBp65 in synovial tissues was analyzed by western blot assay. NF‐κB DNA‐binding activity was measured by enzyme linked immunosorbent assay. Paeonol markedly lowered the paw volume, gait score, and histological score in MIA rats. Mechanistically, paeonol markedly reduced the expression of TNF‐α, IL‐1β, and IL‐6 in synovial tissues of MIA rats. In addition, the elevated level of p65 in nucleus and NF‐κB DNA‐binding activity in synovial tissues of MIA rats were reduced significantly by paeonol treatment. These findings suggest that paeonol exerts anti‐inflammatory effect in MIA rats through inhibiting expression of proinflammatory cytokines and NF‐κB activation.     

Parthenolide ameliorates intracerebral hemorrhage‐induced brain injury in rats

Neuroinflammation and oxidative stress are key contributors to intracranial hemorrhage (ICH)‐induced brain injury. Parthenolide (PN) is a sesquiterpene lactone that has been observed to have antioxidative, anti‐inflammatory, and neuroprotective potentials. However, the role of PN in ICH remains unclear. Therefore, we investigated the neuroprotective effects and underlying mechanisms of PN on an experimental model of ICH in rats. Our results showed that PN treatment improved neurological deficit and brain edema in ICH rats. The ipsilateral hemispheres of the brain were separated and homogenized. The concentrations of TNF‐α, interleukin (IL)‐6, and IL‐17 in the homogenates were detected by enzyme‐linked immunosorbent assay. We found that PN inhibited the production of proinflammatory cytokines in an ICH rat model. The ROS and glutathione (GSH) levels, as well as the activity of superoxide dismutase (SOD) in the homogenates were measured. ICH caused an increase in ROS level, and the decreases in GSH level and SOD activity were mitigated by PN treatment. Furthermore, PN significantly suppressed the expressions of active caspase‐3 and Bax in ipsilateral hemispheres of the brain at Day 3 after ICH, as well as increased the surviving neurons. Finally, the ICH‐induced activation of TLR4/NF‐κB pathway was suppressed by PN treatment. These findings suggested that PN could be beneficial in the therapeutic strategy for ICH treatment.     

Polysaccharide extracted from Potentilla anserina L ameliorate acute hypobaric hypoxia‐induced brain impairment in rats

High altitude cerebral edema (HACE) is a high altitude malady caused by acute hypobaric hypoxia (AHH), in which pathogenesis is associated with oxidative stress and inflammatory cytokines. Potentilla anserina L is mainly distributed in Tibetan Plateau, and its polysaccharide possesses many physiological and pharmacological properties. In the present study, the protective effect and potential treatment mechanism of Potentilla anserina L polysaccharide (PAP) in HACE were explored. First, we measured the brain water content and observed the pathological changes in brain tissues, furthermore, malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), and glutathione (GSH) were evaluated by kits. Finally, the protein contents and mRNA expressions of pro‐inflammatory (IL‐1β, IL‐6, TNF‐α, vascular endothelial cell growth factor [VEGF], NF‐κB, and hypoxia inducible factor‐1 α [HIF‐1α]) were detected by ELISA kits, RT‐PCR, and western blotting. The results demonstrated that PAP reduced the brain water content, alleviated brain tissue injury, reduce the levels of MDA and NO, and increased the activity of SOD and GSH level. In addition, PAP blocking the NF‐κB and HIF‐1α signaling pathway activation inhibited the generation of downstream pro‐inflammatory cytokines (IL‐1β, IL‐6, TNF‐α, and VEGF). Therefore, PAP has a potential to treat and prevent of HACE by suppression of oxidative stress and inflammatory response.