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Fulltext Binding mode analysis of zerumbone to key signal proteins in the tumor necrosis factor pathway

Fatima A, Abdul AB, Abdullah R, Karjiban RA, Lee VS

Int J Mol Sci, 2015 Jan 26;16(2):2747-66.
PMID: 25629232 DOI: 10.3390/ijms16022747

Breast cancer is the second most common cancer among women worldwide. Several signaling pathways have been implicated as causative and progression agents. The tumor necrosis factor (TNF) α protein plays a dual role in promoting and inhibiting cancer depending largely on the pathway initiated by the binding of the protein to its receptor. Zerumbone, an active constituent of Zingiber zerumbet, Smith, is known to act on the tumor necrosis factor pathway upregulating tumour necrosis factor related apoptosis inducing ligand (TRAIL) death receptors and inducing apoptosis in cancer cells. Zerumbone is a sesquiterpene that is able to penetrate into the hydrophobic pockets of proteins to exert its inhibiting activity with several proteins. We found a good binding with the tumor necrosis factor, kinase κB (IKKβ) and the Nuclear factor κB (NF-κB) component proteins along the TNF pathway. Our results suggest that zerumbone can exert its apoptotic activities by inhibiting the cytoplasmic proteins. It inhibits the IKKβ kinase that activates the NF-κB and also binds to the NF-κB complex in the TNF pathway. Blocking both proteins can lead to inhibition of cell proliferating proteins to be downregulated and possibly ultimate induction of apoptosis.

Matched MeSH terms: I-kappa B Kinase/metabolism
Fulltext In vitro and in vivo anti-inflammatory activity of 17-O-acetylacuminolide through the inhibition of cytokines, NF-κB translocation and IKKβ activity

Achoui M, Appleton D, Abdulla MA, Awang K, Mohd MA, Mustafa MR

PLoS One, 2010;5(12):e15105.
PMID: 21152019 DOI: 10.1371/journal.pone.0015105

17-O-acetylacuminolide (AA), a diterpenoid labdane, was isolated for the first time from the plant species Neouvaria foetida. The anti-inflammatory effects of this compound were studied both in vitro and in vivo.

Matched MeSH terms: I-kappa B Kinase/metabolism*
Fulltext Withaferin A protects against palmitic acid-induced endothelial insulin resistance and dysfunction through suppression of oxidative stress and inflammation

Batumalaie K, Amin MA, Murugan DD, Sattar MZ, Abdullah NA

Sci Rep, 2016 06 02;6:27236.
PMID: 27250532 DOI: 10.1038/srep27236

Activation of inflammatory pathways via reactive oxygen species (ROS) by free fatty acids (FFA) in obesity gives rise to insulin resistance and endothelial dysfunction. Withaferin A (WA), possesses both antioxidant and anti-inflammatory properties and therefore would be a good strategy to suppress palmitic acid (PA)-induced oxidative stress and inflammation and hence, insulin resistance and dysfunction in the endothelium. Effect of WA on PA-induced insulin resistance in human umbilical vein endothelial cells (HUVECs) was determined by evaluating insulin signaling mechanisms whilst effect of this drug on PA-induced endothelial dysfunction was determined in acetylcholine-mediated relaxation in isolated rat aortic preparations. WA significantly inhibited ROS production and inflammation induced by PA. Furthermore, WA significantly decreased TNF-α and IL-6 production in endothelial cells by specifically suppressing IKKβ/NF-κβ phosphorylation. WA inhibited inflammation-stimulated IRS-1 serine phosphorylation and improved the impaired insulin PI3-K signaling, and restored the decreased nitric oxide (NO) production triggered by PA. WA also decreased endothelin-1 and plasminogen activator inhibitor type-1 levels, and restored the impaired endothelium-mediated vasodilation in isolated aortic preparations. These findings suggest that WA inhibited both ROS production and inflammation to restore impaired insulin resistance in cultured endothelial cells and improve endothelial dysfunction in rat aortic rings.

Matched MeSH terms: I-kappa B Kinase/metabolism
Tumour necrosis factor alpha down-regulates the expression of peroxisome proliferator activated receptor alpha (PPARα) in human hepatocarcinoma HepG2 cells by activation of NF-κB pathway

Lim WS, Ng DL, Kor SB, Wong HK, Tengku-Muhammad TS, Choo QC, et al.

Cytokine, 2013 Jan;61(1):266-74.
PMID: 23141142 DOI: 10.1016/j.cyto.2012.10.007

Peroxisome proliferator activated receptor-alpha (PPARα) plays a major role in the regulation of lipid and glucose homeostasis, and inflammatory responses. The objectives of the study were to systematically investigate the effects of TNF-α and its regulatory pathway on PPARα expression in HepG2 cells using Real-Time RT-PCR and western blot analysis. Here, TNF-α suppressed PPARα mRNA expression in a dose- and time-dependent manner at the level of gene transcription. Pre-treatment of cells with 10μM of Wedelolactone for 2h was sufficient to restore PPARα expression to basal levels and also affected the expression of PPARα-regulated genes. This study also demonstrated that TNF-α represses PPARα expression by augmenting the activity of canonical NF-κB signalling pathway. This was shown by the abrogation of TNF-α-mediated PPARα down-regulation, after both p65 and p50 were knocked down via siRNA. The IKK contributes to IκBα degradation and mediates inducible phosphorylation of p105 at Ser933. Surprisingly, phosphorylation of p65 at Ser468 and Ser536 were severely abrogated with Wedelolactone inhibition, suggesting that Ser468 and Ser536, but not Ser276, may mediate the TNF-α inhibitory action on PPARα gene expression. These results suggest that TNF-α might, at least in part, suppress PPARα expression through activation of IKK/p50/p105/p65 pathway. Furthermore, phosphorylation of p65 at Ser468 and Ser536 may play a crucial role in the mechanism that limits PPARα production in the human HepG2 cells.

Matched MeSH terms: I-kappa B Kinase/metabolism
Evaluation of antiarthritic activity of nimbolide against Freund's adjuvant induced arthritis in rats

Cui X, Wang R, Bian P, Wu Q, Seshadri VDD, Liu L

Artif Cells Nanomed Biotechnol, 2019 Dec;47(1):3391-3398.
PMID: 31394949 DOI: 10.1080/21691401.2019.1649269

Nimbolide, a triterpenoid isolated from flower of neem tree possess various therapeutic properties. The objective of the study was to assess the anti-arthritic activity of nimbolide in arthritis induced rats. Nimbolide (20 mg/kg per day) was given orally to arthritic rats induced with Complete Freund's Adjuvant and changes in paw volume, body weight, organ indices (thymus and spleen), arthritic score, biochemical parameters and proinflammatory cytokines levels were determined. Histopathological analysis was also performed. Western blot analysis was also performed. Rats treated with nimbolide displayed marked reduction in arthritic score, organ indices, volume of paw, edema formation, along with substantial enhancement in body weight. Histopathological findings showed significant reduction in destruction of joints and inflammation following nimbolide treatment. The protective action of arthritic rats treated with nimbolide was also substantiated by molecular and biochemical studies. The results of the study show that nimbolide treatment has markedly enhanced health and reduced inflammation via lessening the proinflammatory cytokines expression in arthritic rats. Hence, nimbolide may be used as a potent therapeutic drug in treating rheumatoid arthritis.

Matched MeSH terms: I-kappa B Kinase/metabolism
Synthesis of unsymmetrical monocarbonyl curcumin analogues with potent inhibition on prostaglandin E2 production in LPS-induced murine and human macrophages cell lines

Mohd Aluwi MF, Rullah K, Yamin BM, Leong SW, Abdul Bahari MN, Lim SJ, et al.

Bioorg Med Chem Lett, 2016 05 15;26(10):2531-8.
PMID: 27040659 DOI: 10.1016/j.bmcl.2016.03.092

The syntheses and bioactivities of symmetrical curcumin and its analogues have been the subject of interest by many medicinal chemists and pharmacologists over the years. To improve our understanding, we have synthesized a series of unsymmetrical monocarbonyl curcumin analogues and evaluated their effects on prostaglandin E2 production in lipopolysaccharide-induced RAW264.7 and U937 cells. Initially, compounds 8b and 8c exhibited strong inhibition on the production of PGE2 in both LPS-stimulated RAW264.7 (8b, IC50=12.01μM and 8c, IC50=4.86μM) and U937 (8b, IC50=3.44μM and 8c, IC50=1.65μM) cells. Placing vanillin at position Ar2 further improved the potency when both compounds 15a and 15b significantly lowered the PGE2 secretion level (RAW264.7: 15a, IC50=0.78μM and 15b, IC50=1.9μM while U937: 15a, IC50=0.95μM and 15b, IC50=0.92μM). Further experiment showed that compounds 8b, 8c, 15a and 15b did not target the activity of downstream inflammatory COX-2 mediator. Finally, docking simulation on protein targets COX-2, IKK-β, ERK, JNK2, p38α and p38β were performed using the conformation of 15a determined by single-crystal XRD.

Matched MeSH terms: I-kappa B Kinase/metabolism
1'S-1'-acetoxyeugenol acetate: a novel phenylpropanoid from Alpinia conchigera enhances the apoptotic effects of paclitaxel in MCF-7 cells through NF-κB inactivation

In LL, Azmi MN, Ibrahim H, Awang K, Nagoor NH

Anticancer Drugs, 2011 Jun;22(5):424-34.
PMID: 21346553 DOI: 10.1097/CAD.0b013e328343cbe6

In this study, the apoptotic mechanism and combinatorial chemotherapeutic effects of the cytotoxic phenylpropanoid compound 1'S-1'-acetoxyeugenol acetate (AEA), extracted from rhizomes of the Malaysian ethnomedicinal plant Alpinia conchigera Griff. (Zingiberaceae), on MCF-7 human breast cancer cells were investigated for the first time. Data from cytotoxic and apoptotic assays such as live and dead and poly-(ADP-ribose) polymerase cleavage assays indicated that AEA was able to induce apoptosis in MCF-7 cells, but not in normal human mammary epithelial cells. A microarray global gene expression analysis of MCF-7 cells, treated with AEA, suggested that the induction of tumor cell death through apoptosis was modulated through dysregulation of the nuclear factor-kappaB (NF-κB) pathway, as shown by the reduced expression of various κB-regulated gene targets. Consequent to this, western blot analysis of proteins corresponding to the NF-κB pathway indicated that AEA inhibited phosphorylation levels of the inhibitor of κB-kinase complex, resulting in the elimination of apoptotic resistance originating from NF-κB activation. This AEA-based apoptotic modulation was elucidated for the first time in this study, and gave rise to the proposal of an NF-κB model termed the 'Switching/Alternating Model.' In addition to this, AEA was also found to synergistically enhance the proapoptotic effects of paclitaxel, when used in combination with MCF-7 cells, presumably by a chemosensitizing role. Therefore, it was concluded that AEA isolated from the Malaysian tropical ginger (A. conchigera) served as a very promising candidate for further in-vivo development in animal models and in subsequent clinical trials involving patients with breast-related malignancies.

Matched MeSH terms: I-kappa B Kinase/metabolism
Fulltext Alpha-tomatine attenuation of in vivo growth of subcutaneous and orthotopic xenograft tumors of human prostate carcinoma PC-3 cells is accompanied by inactivation of nuclear factor-kappa B signaling

Lee ST, Wong PF, He H, Hooper JD, Mustafa MR

PLoS One, 2013;8(2):e57708.
PMID: 23437404 DOI: 10.1371/journal.pone.0057708

Nuclear factor-kappa B (NF-κB) plays a role in prostate cancer and agents that suppress its activation may inhibit development or progression of this malignancy. Alpha (α)-tomatine is the major saponin present in tomato (Lycopersicon esculentum) and we have previously reported that it suppresses tumor necrosis factor-alpha (TNF-α)-induced nuclear translocation of nuclear factor-kappa B (NF-κB) in androgen-independent prostate cancer PC-3 cells and also potently induces apoptosis of these cells. However, the precise mechanism by which α-tomatine suppresses NF-κB nuclear translocation is yet to be elucidated and the anti-tumor activity of this agent in vivo has not been examined.

Matched MeSH terms: I-kappa B Kinase/metabolism
Fulltext Nickel(II) complex of polyhydroxybenzaldehyde N4-thiosemicarbazone exhibits anti-inflammatory activity by inhibiting NF-κB transactivation

Shawish HB, Wong WY, Wong YL, Loh SW, Looi CY, Hassandarvish P, et al.

PLoS One, 2014;9(6):e100933.
PMID: 24977407 DOI: 10.1371/journal.pone.0100933

BACKGROUND: The biological properties of thiosemicarbazone have been widely reported. The incorporation of some transition metals such as Fe, Ni and Cu to thiosemicarbazone complexes is known to enhance its biological effects. In this study, we incorporated nickel(II) ions into thiosemicarbazone with N4-substitution groups H3L (H; H3L1, CH3; H3L2, C6H5; H3L3 and C2H5; H3L4) and examined its potential anti-inflammatory activity.
METHODOLOGY/PRINCIPAL FINDINGS: Four ligands (1-4) and their respective nickel-containing complexes (5-8) were synthesized and characterized. The compounds synthesized were tested for their effects on NF-κB nuclear translocation, pro-inflammatory cytokines secretion and NF-κB transactivation activity. The active compound was further evaluated on its ability to suppress carrageenan-induced acute inflammation in vivo. A potential binding target of the active compound was also predicted by molecular docking analysis.
CONCLUSIONS/SIGNIFICANCE: Among all synthesized compounds tested, we found that complex [Ni(H2L1)(PPh3)]Cl (5) (complex 5), potently inhibited IκBα degradation and NF-κB p65 nuclear translocation in LPS-stimulated RAW264.7 cells as well as TNFα-stimulated HeLa S3 cells. In addition, complex 5 significantly down-regulated LPS- or TNFα-induced transcription of NF-κB target genes, including genes that encode the pro-inflammatory cytokines TNFα, IFNβ and IL6. Luciferase reporter assays confirmed that complex 5 inhibited the transactivation activity of NF-κB. Furthermore, the anti-inflammatory effect of complex 5 was also supported by its suppressive effect on carrageenan-induced paw edema formation in wild type C57BL/6 mice. Interestingly, molecular docking study showed that complex 5 potentially interact with the active site of IKKβ. Taken together, we suggest complex 5 as a novel NF-κB inhibitor with potent anti-inflammatory effects.

Matched MeSH terms: I-kappa B Kinase/metabolism