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The N-terminus of Histone H3 is proteolytically processed in aged chicken liver. A histone H3 N-terminus specific endopeptidase (named H3ase) has been purified from the nuclear extract of aged chicken liver. By sequencing and a series of biochemical methods including the demonstration of H3ase activity in bacterially expressed GDH, it was established that the H3ase activity was a moonlighting protease activity of glutamate dehydrogenase (GDH). However, the active site for the H3ase in the GDH remains elusive. Here, using cross-linking studies of the homogenously purified H3ase, we show that the GDH and the H3ase remain in the same native state. Further, the H3ase and GDH activities could be uncoupled by partial denaturation of GDH, suggesting strong evidence for the involvement of different active sites for GDH and H3ase activities. Through densitometry of the H3ase clipped H3 products, the H3ase activity was quantified and it was compared with the GDH activity of the chicken liver nuclear GDH. Furthermore, the H3ase mostly remained distributed in the perinuclear area as demonstrated by MNase digestion and immuno-localization of H3ase in chicken liver nuclei, as well as cultured mouse hepatocyte cells, suggesting that H3ase demonstrated regulated access to the chromatin. The present study thus broadly compares the H3ase and GDH activities of the chicken liver GDH., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The nuclear events of a eukaryotic cell, such as replication, transcription, recombination and repair etc. require the transition of the compactly arranged chromatin into an uncompacted state and vice-versa. This is mediated by post-translational modification of the histones, exchange of histone variants and ATP-dependent chromatin remodeling. The SWI/SNF chromatin remodeling complexes are one of the most well characterized families of chromatin remodelers. In addition to their role in modulating chromatin, they have also been assigned roles in cancer and health-related anomalies such as developmental, neurocognitive, and intellectual disabilities. Owing to their vital cellular and medical connotations, developing an understanding of the structural and functional aspects of the complex becomes imperative. However, due to the intricate nature of higher-order chromatin as well as compositional heterogeneity of the SWI/SNF complex, intra-species isoforms and inter-species homologs, this often becomes challenging. To this end, the present review attempts to present an amalgamated perspective on the discovery, structure, function, and regulation of the SWI/SNF complex., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Histones are classically known to organize the eukaryotic DNA into chromatin. They are one of the key players in regulating transcriptionally permissive and non-permissive states of the chromatin. Nevertheless, their context-dependent appearance within the cytoplasm and systemic circulation has also been observed. The past decade has also witnessed few scientific communications on the existence of vesicle-associated histones. Diverse groups have attempted to determine the significance of these extra-nuclear histones so far, with many of those studies still underway. Of note amongst these are interactions of extra-nuclear or free histones with cellular membranes, mediated by mutual cationic and anionic natures, respectively. It is here aimed to consolidate the mechanism of formation of extra-nuclear histones; implications of histone-induced membrane destabilization and explore the mechanisms of their association/release with extracellular vesicles, along with the functional aspects of these extra-nuclear histones in cell and systemic physiology., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Exposure to ionizing radiation (IR) set a series of deleterious events causing acute radiation syndrome and mortality, posing the need for a potent and safe radio-protective drug. IR induces cell death predominantly by causing oxidative stress and macromolecular damage. The pre-existing antioxidant defence machinery of the cellular system plays a crucial role in protecting the cells against oxidative stress by activation of Nrf2. The current study was undertaken to investigate the radio-protective potential of sphingosine kinase inhibitor (SKI-II), which was demonstrated to activate Nrf2 signaling. The safety and efficacy of SKI-II were evaluated with cell cytotoxicity, proliferation index, and clonogenic survival assays in different cell lines, namely Raw 264.7, INT-407, IEC-6 and NIH/3T3 cell lines. A safe dose of SKI-II was found radio-protective in all the cell lines linked with the activated antioxidant defence system, thereby resulting in the amelioration of IR induced oxidative stress. SKI-II pretreatment also significantly reduced DNA damage, micronuclei expression, and accelerated DNA repair kinetics as compared to IR exposed cells. Reduced oxidative stress and enhanced DNA repair significantly reduced apoptosis and suppressed the pro-death signaling associated with IR exposure. Furthermore, the in-vitro observation was verified in the in-vivo model (C57 BL/6). The Intra-peritoneal (IP) administration of SKI-II, 2 h before a lethal dose of IR exposure (7.5 Gy) resulted in 75% survival. These results imply that SKI-II ameliorates IR-induced oxidative stress and cell death by inducing anti-oxidant defence system and DNA repair pathways, thus strengthening its potential to be used as radiation countermeasure., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The chromatin remodeling activity of mammalian SWI/SNF complex is carried out by either Brahma (BRM) or Brahma-related gene (BRG-1). The BRG-1 regulates genes involved in cell proliferation, whereas BRM is associated with cell differentiation, and arrest of cell growth. Global modifications of histones and expression of genes of chromatin-remodeling subunits have not been studied in in vivo model systems. In the present study, we investigate epigenetic modifications of histones and the expression of genes in thioacetamide (TAA)-induced liver injury and regeneration in a mouse model. In the present study, we report that hepatocyte proliferation and H3S10 phosphorylation occur during 60 to 72 h post TAA treatment in mice. Furthermore, there was change in the H3K9 acetylation and H3K9 trimethylation pattern with respect to liver injury and regeneration phase. Looking into the expression pattern of Brg-1 and Brm, it is evident that they contribute substantially to the process of liver regeneration. The SWI/SNF remodeler might contain BRG-1 as its ATPase subunit during injury phase. Whereas, BRM-associated SWI/SNF remodeler might probably be predominant during decline of injury phase and initiation of regeneration phase. Furthermore, during the regeneration phase, BRG-1-containing remodeler again predominates. Considering all these observations, the present study depicts an interplay between chromatin interacting machineries in different phases of thioacetamide-induced liver injury and regeneration.

Site-specific proteolysis of the N or C-terminus of histone tails has emerged as a novel form of irreversible post-translational modifications assigned to histones. Though there are many reports describing histone specific proteolysis, there are very few studies on purification of a histone specific protease. Here, we demonstrate a histone H3 specific protease (H3ase) activity in chicken liver nuclear extract. H3ase was purified to homogeneity and identified as glutamate dehydrogenase (GDH) by sequencing. A series of biochemical experiments further confirmed that the H3ase activity was due to GDH. The H3ase clipped histone H3 products were sequenced by N-terminal sequencing and the precise clipping sites of H3ase were mapped. H3ase activity was only specific to chicken liver as it was not demonstrated in other tissues like heart, muscle and brain of chicken. We assign a novel serine like protease activity to GDH which is specific to histone H3., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Radiation-induced DNA damage initiates a series of overlapping responses that include DNA damage recognition and repair, induction of cell cycle checkpoints, senescence and/or apoptosis. This study assessed the DNA damage response and whole genome expression profile in two mammalian cell lines (HEK and U87) in response to (5-{4-methylpiperazin-1-yl}-2-[2'-(3,4-dimethoxyphenyl)-5'-benzimidazolyl] benzimidazole) DMA and ionizing radiation. DMA has been shown to act as a potent radiation protector, yielding significant levels of protection, i.e., 20.9% in HEK cells and 21.2% in U87 cells. Our findings revealed treatment with DMA significantly reduced γ-H2AX, 53BP1 and Rad51 foci formation after irradiation. MAP kinase, WNT signaling and p53 pathways were found to be activated in DMA-treated cells. In addition, the DNA damage response genes, HSP70, HSPD1, PRDX1, PRX, CALR, NPM, UBC, and SET showed differential regulation in DMA, DMA + radiation and radiation-treated cells. The data suggest that DMA-influenced repertoire of repair proteins, which are an indispensable part of the cell, interplay with each other to reduce DNA damage and maintain the genomic integrity of the cell.

The proteolysis of the N- or the C-terminal tails of histones have recently emerged as a novel form of irreversible posttranslational modifications of histones. However, there are very few reports describing purification of a histone specific protease. Here, we report a histone H2A specific protease (H2Asp) activity in the chicken liver nuclear extract. The H2Asp was purified to homogeneity and was found to be a ~10.5kDa protein. It demonstrated high specificity to histone H2A and was an aspartic acid like protease as shown by protease inhibition assay. The H2Asp, in the in vitro cleavage assay generated a single clipped H2A product which comigrated along with histone H4 in the SDS-PAGE and migrated as a single band when single H2A was used as substrates. The expression of H2Asp was independent of age and was tissue specific, which was demonstrated only in the nuclear extracts of chicken liver and not from the same of other tissues like brain, muscles and erythrocytes. It was also seen that H2Asp activity also exists in other classes of vertebrates from Pisces to Mammals. This report forms the first such report describing purification of a histone H2A specific protease., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Objective: To ascertain the association of -3826 A/G polymorphism with blood pressure and different obesity markers., Design and Subjects: A total of 96 adult participants (49 males, 47 females) were studied. Anthropometric measurements and blood pressure were taken using standardized techniques. Obesity indices of body mass index (BMI), waist hip ratio (WHR), waist height ratio (WHtR) and grand mean thickness (GMT) were computed. For genetic analysis, DNA was extracted from 50 microL blood., Results: A statistically significant difference between various genotypes of UCP1 and BMI, GMT, systolic blood pressure, diastolic blood pressure was found among females. In GGC homozygote, blood pressure showed positive and significant association with fat percentage and GMT (P < .001). Waist circumference, WHR, WHtR and BMI also showed positive association with blood pressure in heterozygous and homozygous GG form., Conclusion: This study links the GG homozygous form of UCP1 with obesity and blood pressure among females only.

Glutamate dehydrogenase (GDH) enzyme is recently being reported to be present in the nucleus in addition to the mitochondria in a number of organisms. Here we investigated the distribution of GDH in liver and brain tissues of chicken. Polyclonal anti-GDH antibody against bovine GDH was raised by us, which was later shown to be immunereactive to chicken GDH. The nuclear and the mitochondrial extracts from liver and brain tissues of chicken were made as described. By quantitative immunoreactivity, it was revealed that the nuclear GDH expressed in comparable efficiencies in the liver and brain. However, the activity of the brain nuclear GDH was lower than the liver counterparts. The allosteric regulation pattern for the brain nuclear GDH was also different from the other corresponding fractions and it was speculated that the brain nuclear GDH was inactive. The liver and brain nuclear GDH were purified to homogeneity and comparison of specific activities of both the GDH ruled out the existence of any inhibitor in the brain nuclear GDH. It is hypothesized that the inactivation of the brain nuclear GDH in chicken could be due to some already known posttranslational modification. The present report throws light on the differential regulation pattern of GDH enzyme.

Triptolide, a diterpene triepoxide, from the Chinese herb Tripterygium wilfordii Hook.f, exerts its anti-inflammatory and immunosuppressive activities by inhibiting the transcription factor nuclear factor-κB (NF-κB) pathway, through a mechanism not yet fully understood. We found that triptolide, in nanomolar concentrations, suppressed both constitutive and inducible NF-κB activation, but did not directly inhibit binding of p65 to the DNA. The diterpene did block TNF-induced ubiquitination, phosphorylation, and degradation of IκBα, the inhibitor of NF-κB and inhibited acetylation of p65 through suppression of binding of p65 to CBP/p300. Triptolide also inhibited the IκBα kinase (IKK) that activates NF-κB and phosphorylation of p65 at serine 276, 536. Furthermore, the NF-κB reporter activity induced by TNF-TNFR1-TRADD-TRAF2-NIK-TAK1-IKKβ was abolished by the triepoxide. Triptolide also abrogated TNF-induced expression of cell survival proteins (XIAP, Bcl-x(L), Bcl-2, survivin, cIAP-1 and cIAP-2), cell proliferative proteins (cyclin D1, c-myc and cyclooxygenase-2), and metastasis proteins (ICAM-1 and MMP-9). This led to enhancement of apoptosis induced by TNF, taxol, and thalidomide by the diterpene and to suppression of tumor invasion. Overall, our results demonstrate that triptolide can block the inflammatory pathway activated by TNF-TNFR1-TRADD-TRAF2-NIK-TAK1-IKK, sensitizes cells to apoptosis, and inhibits invasion of tumor cells., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Inflammation, although first characterized by Cornelius Celsus, a physician in first Century Rome, it was Rudolf Virchow, a German physician in nineteenth century who suggested a link between inflammation and cancer, cardiovascular diseases, diabetes, pulmonary diseases, neurological diseases and other chronic diseases. Extensive research within last three decades has confirmed these observations and identified the molecular basis for most chronic diseases and for the associated inflammation. The transcription factor, Nuclear Factor-kappaB (NF-kappaB) that controls over 500 different gene products, has emerged as major mediator of inflammation. Thus agents that can inhibit NF-kappaB and diminish chronic inflammation have potential to prevent or delay the onset of the chronic diseases and further even treat them. In an attempt to identify novel anti-inflammatory agents which are safe and effective, in contrast to high throughput screen, we have turned to "reverse pharmacology" or "bed to benchside" approach. We found that Ayurveda, a science of long life, almost 6,000 years old, can serve as a "goldmine" for novel anti-inflammatory agents used for centuries to treat chronic diseases. The current review is an attempt to provide description of various Ayurvedic plants currently used for treatment, their active chemical components, and the inflammatory pathways that they inhibit.

Activation of nuclear factor (NF)-κB, one of the most investigated transcription factors, has been found to control multiple cellular processes in cancer including inflammation, transformation, proliferation, angiogenesis, invasion, metastasis, chemoresistance and radioresistance. NF-κB is constitutively active in most tumor cells, and its suppression inhibits the growth of tumor cells, leading to the concept of 'NF-κB addiction' in cancer cells. Why NF-κB is constitutively and persistently active in cancer cells is not fully understood, but multiple mechanisms have been delineated including agents that activate NF-κB (such as viruses, viral proteins, bacteria and cytokines), signaling intermediates (such as mutant receptors, overexpression of kinases, mutant oncoproteins, degradation of IκBα, histone deacetylase, overexpression of transglutaminase and iNOS) and cross talk between NF-κB and other transcription factors (such as STAT3, HIF-1α, AP1, SP, p53, PPARγ, β-catenin, AR, GR and ER). As NF-κB is 'pre-active' in cancer cells through unrelated mechanisms, classic inhibitors of NF-κB (for example, bortezomib) are unlikely to mediate their anticancer effects through suppression of NF-κB. This review discusses multiple mechanisms of NF-κB activation and their regulation by multitargeted agents in contrast to monotargeted agents, thus 'one size does not fit all' cancers.

Extensive research within the last two decades has revealed that most chronic illnesses, including cancer, diabetes, and cardiovascular and pulmonary diseases, are mediated through chronic inflammation. Thus, suppressing chronic inflammation has the potential to delay, prevent, and even treat various chronic diseases, including cancer. Various nutraceuticals from fruits, vegetables, vitamins, spices, legumes, and traditional Chinese and Ayurvedic medicine have been shown to safely suppress proinflammatory pathways; however, their low bioavailability in vivo limits their use in preventing and treating cancer. We describe here the potential of nanotechnology to fill this gap. Several nutraceuticals, including curcumin, green tea polyphenols, coenzyme Q, quercetin, thymoquinone and others, have been packaged as nanoparticles and proven to be useful in "nanochemoprevention" and "nano-chemotherapy"., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Extensive research during the past 2 decades has revealed the mechanism by which continued oxidative stress can lead to chronic inflammation, which in turn could mediate most chronic diseases including cancer, diabetes, and cardiovascular, neurological, and pulmonary diseases. Oxidative stress can activate a variety of transcription factors including NF-κB, AP-1, p53, HIF-1α, PPAR-γ, β-catenin/Wnt, and Nrf2. Activation of these transcription factors can lead to the expression of over 500 different genes, including those for growth factors, inflammatory cytokines, chemokines, cell cycle regulatory molecules, and anti-inflammatory molecules. How oxidative stress activates inflammatory pathways leading to transformation of a normal cell to tumor cell, tumor cell survival, proliferation, chemoresistance, radioresistance, invasion, angiogenesis, and stem cell survival is the focus of this review. Overall, observations to date suggest that oxidative stress, chronic inflammation, and cancer are closely linked., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Although metastasis accounts for >90% of cancer-related deaths, no therapeutic that targets this process has yet been approved. Because the chemokine receptor CXCR4 is one of the targets closely linked with tumor metastasis, inhibitors of this receptor have the potential to abrogate metastasis. In the current report, we demonstrate that celastrol can downregulate the CXCR4 expression on breast cancer MCF-7 cells stably transfected with HER2, an oncogene known to induce the chemokine receptor. Downregulation of CXCR4 by the triterpenoid was not cell type-specific as downregulation occurred in colon cancer, squamous cell carcinoma, and pancreatic cancer cells. Decrease in CXCR4 expression was not due to proteolysis as neither proteasome inhibitors nor lysosomal stabilization had any effect. Quantitative reverse transcription polymerase chain reaction analysis revealed that downregulation of CXCR4 messenger RNA (mRNA) by celastrol occurred at the translational level. Chromatin immunoprecipitation analysis revealed regulation at the transcriptional level as well. Abrogation of the chemokine receptor by celastrol or by gene-silencing was accompanied by suppression of invasiveness of colon cancer cells induced by CXCL12, the ligand for CXCR4. This effect was not cell type-specific as celastrol also abolished invasiveness of pancreatic tumor cells, and this effect again correlated with the disappearance of both the CXCR4 mRNA and CXCR4 protein. Other triterpenes, such as withaferin A and gedunin, which are known to inhibit Hsp90, did not downregulate CXCR4 expression, indicating that the effects were specific to celastrol. Overall, these results show that celastrol has potential in suppressing invasion and metastasis of cancer cells by down-modulation of CXCR4 expression.

Reverse pharmacology, also called the "bedside to bench" approach, that deals with new uses for a well known molecular entity has been used extensively in cancer drug development to identify novel compounds and delineate their mechanisms of action. Here, we show that nimbolide, a triterpenoid isolated from Azadirachta indica, enhanced the apoptosis induced by inflammatory cytokines and chemotherapeutic agents in tumor cells. This limonoid abrogated the expression of proteins associated with cell survival (Bcl-2, Bcl-xL, IAP-1, and IAP-2), proliferation (cyclin D1), invasion (MMP-9), and angiogenesis (VEGF), all regulated by nuclear factor (NF)-κB. Nimbolide inhibited the activation of NF-κB induced by carcinogens and inflammatory stimuli. Constitutively active NF-κB found in most tumor cells was also inhibited. We found that suppression of NF-κB activation by nimbolide was caused by inhibition of IκB kinase (IKK), which led to suppression of IκBα phosphorylation and degradation, nuclear translocation, DNA binding, and gene transcription. Reducing agent reversed the action of the limonoid, suggesting the involvement of a cysteine residue. Replacement of Cys(179) of IKK-β with alanine abolished the effect of nimbolide, suggesting that Cys(179) plays a critical role in inhibiting the NF-κB activation. Overall, our results indicate that nimbolide can sensitize tumor cells to chemotherapeutic agents through interaction with IKK, leading to inhibition of NF-κB-regulated proteins.

The discovery of new uses for older, clinically approved drugs is one way to expedite drug development for cancer. Thiocolchicoside, a semisynthetic colchicoside from the plant Gloriosa superba, is a muscle relaxant and used to treat rheumatologic and orthopedic disorders because of its analgesic and anti-inflammatory mechanisms. Given that activation of the transcription factor NF-κB plays a major role in inflammation and tumorigenesis, we postulated that thiocolchicoside would inhibit NF-κB and exhibit anticancer effects through the modulation of NF-κB-regulated proteins. We show that thiocolchicoside inhibited proliferation of leukemia, myeloma, squamous cell carcinoma, breast, colon, and kidney cancer cells. Formation of tumor colonies was also suppressed by thiocolchicoside. The colchicoside induced apoptosis, as indicated by caspase-3 and poly(ADP-ribose) polymerase cleavage, and suppressed the expression of cell survival [e.g., Bcl-2, X-linked inhibitor of apoptosis (XIAP), MCL-1, bcl-xL, cIAP-1, cIAP-2, and cFLIP] proteins. Cell proliferation biomarkers such as c-MYC and phosphorylation of phosphoinositide 3-kinase and glycogen synthase kinase 3β were also blocked by thiocolchicoside. Because most cell survival and proliferation gene products are regulated by NF-κB, we studied the effect of thiocolchicoside on this transcription factor and found that thiocolchicoside inhibited NF-κB activation, degradation of inhibitory κBα (IκBα), IκBα ubiquitination, and phosphorylation, abolished the activation of IκBα kinase, and suppressed p65 nuclear translocation. This effect of thiocolchicoside on the NF-κB pathway led to inhibition of NF-κB reporter activity and cyclooxygenase-2 promoter activity. Our results indicate that thiocolchicoside exhibits anticancer activity through inhibition of NF-κB and NF-κB-regulated gene products, which provides novel insight into a half-century old drug., (©2010 AACR.)

Curcumin, a yellow pigment present in the spice turmeric (Curcuma longa), has been linked with multiple beneficial activities, but its optimum potential is limited by poor bioavailability, in part due to the lack of solubility in aqueous solvents. To overcome the solubility problem, we have recently developed a novel cyclodextrin complex of curcumin (CDC) and examined here this compound for anti-inflammatory and antiproliferative effects. Using the electrophoretic mobility shift assay, we found that CDC was more active than free curcumin in inhibiting TNF-induced activation of the inflammatory transcription factor NF-kappaB and in suppressing gene products regulated by NF-kappaB, including those involved in cell proliferation (cyclin D1), invasion (MMP-9), and angiogenesis (VEGF). CDC was also more active than free curcumin in inducing the death receptors DR4 and DR5. Annexin V staining, cleavage of caspase-3 and PARP, and DNA fragmentation showed that CDC was more potent than free curcumin in inducing apoptosis of leukemic cells. Antiproliferative assays also demonstrated that CDC was more active than free curcumin in suppressing proliferation of various cancer cell lines. The cyclodextrin vehicle had no effect in these assays. Compared with free curcumin, CDC had a greater cellular uptake and longer half-life in the cells. Overall we demonstrated that CDC had superior attributes compared with free curcumin for cellular uptake and for antiproliferative and anti-inflammatory activities., (Copyright (c) 2010 Elsevier Inc. All rights reserved.)

Crotepoxide (a substituted cyclohexane diepoxide), isolated from Kaempferia pulchra (peacock ginger), although linked to antitumor and anti-inflammatory activities, the mechanism by which it exhibits these activities, is not yet understood. Because nuclear factor kappaB (NF-kappaB) plays a critical role in these signaling pathways, we investigated the effects of crotepoxide on NF-kappaB-mediated cellular responses in human cancer cells. We found that crotepoxide potentiated tumor necrosis factor (TNF), and chemotherapeutic agents induced apoptosis and inhibited the expression of NF-kappaB-regulated gene products involved in anti-apoptosis (Bcl-2, Bcl-xL, IAP1,(2) MCl-1, survivin, and TRAF1), apoptosis (Bax, Bid), inflammation (COX-2), proliferation (cyclin D1 and c-myc), invasion (ICAM-1 and MMP-9), and angiogenesis (VEGF). We also found that crotepoxide inhibited both inducible and constitutive NF-kappaB activation. Crotepoxide inhibition of NF-kappaB was not inducer-specific; it inhibited NF-kappaB activation induced by TNF, phorbol 12-myristate 13-acetate, lipopolysaccharide, and cigarette smoke. Crotepoxide suppression of NF-kappaB was not cell type-specific because NF-kappaB activation was inhibited in myeloid, leukemia, and epithelial cells. Furthermore, we found that crotepoxide inhibited TAK1 activation, which led to suppression of IkappaBalpha kinase, abrogation of IkappaBalpha phosphorylation and degradation, nuclear translocation of p65, and suppression of NF-kappaB-dependent reporter gene expression. Overall, our results indicate that crotepoxide sensitizes tumor cells to cytokines and chemotherapeutic agents through inhibition of NF-kappaB and NF-kappaB-regulated gene products, and this may provide the molecular basis for crotepoxide ability to suppress inflammation and carcinogenesis.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a member of the tumor necrosis factor superfamily, is in clinical trials for cancer therapy, but its anticancer potential is limited by the development of resistance. We investigated the ability of tocotrienol (T3), an unsaturated vitamin E present in palm oil, rice bran, barley, oats, and wheat germ, to sensitize tumor cells to TRAIL. Results from esterase staining, colony formation, caspase activation, and sub-G(1) cell cycle arrest revealed that gamma-T3 can sensitize human colon cancer cells to TRAIL. When examined for the mechanism, we found that gamma-T3 significantly downregulated the expression of antiapoptotic proteins (c-IAP2 and Bcl-xL). We also found that gamma-T3, but not tocopherol, induced the expression of the TRAIL receptors death receptor (DR)-4 and DR5. This induction was not cell type specific, as upregulation was also found in pancreatic, kidney, and leukemic cells. Upregulation of DRs by gamma-T3 required the production of reactive oxygen species (ROS), and sequestering of ROS abolished both upregulation of the receptors and potentiation of TRAIL-induced apoptosis. Induction of DRs by gamma-T3 also required activation of extracellular signal-regulated kinase 1 (ERK1), as silencing of ERK1 by specific siRNA abrogated the upregulation of TRAIL receptors. Further, induction of DRs by gamma-T3 required the expression of p53 and Bax, as no induction of the receptors was found in colon cancer cells with deletion of these genes. Overall, our results show that gamma-T3 sensitizes tumor cells to TRAIL by upregulating DRs through the ROS/ERK/p53 pathway and by downregulating cell survival proteins., ((c) 2010 AACR.)

Observational studies have suggested that lifestyle risk factors such as tobacco, alcohol, high-fat diet, radiation, and infections can cause cancer and that a diet consisting of fruits and vegetables can prevent cancer. Evidence from our laboratory and others suggests that agents either causing or preventing cancer are linked through the regulation of inflammatory pathways. Genes regulated by the transcription factor NF- kappaB have been shown to mediate inflammation, cellular transformation, tumor cell survival, proliferation, invasion, angiogenesis, and metastasis. Whereas various lifestyle risk factors have been found to activate NF- kappaB and NF- kappaB-regulated gene products, flavonoids derived from fruits and vegetables have been found to suppress this pathway. The present review describes various flavones, flavanones, flavonols, isoflavones, anthocyanins, and chalcones derived from fruits, vegetables, legumes, spices, and nuts that can suppress the proinflammatory cell signaling pathways and thus can prevent and even treat the cancer., (Georg Thieme Verlag KG Stuttgart-New York.)

Objective: To investigate lipopolysaccharide (LPS)-induced DNA damage in preimplanting embryonic and uterine cells during preimplantation period of pregnancy that may ultimately inhibit the process of implantation in mouse., Design: Animal study., Setting: Academic research environment., Animal(s): Sixty four Park strain female mice., Intervention(s): The "minimum dose" (MD) of LPS was injected intraperitoneally in the pregnant females on day 0.5 of pregnancy, and individual embryos and uterine cells were assessed by comet assay on days 1.5, 2.5, 3.5, and 4.375 of the preimplantation period of pregnancy., Main Outcome Measure(s): Percentage of embryos and uterine cells with tail, mean comet tail length, percentage of fragmented DNA in tail., Result(s): Significantly higher numbers of embryos with higher mean comet tail length and percentage of fragmented DNA in tail were observed in the LPS-treated compared with control animals as the period of pregnancy approaches the stage of implantation. At the same time, DNA damage was also significantly higher in the uterine cells of LPS-treated compared with control animals., Conclusion(s): The MD of LPS can induce DNA damage in the preimplantation-stage embryos and uterine cells, which causes poor embryonic development and improper preparation of uterine horns during the preimplantation period of pregnancy, which may ultimately inhibit the process of implantation in mouse.

Problem: Lipopolysaccharide (LPS) has been postulated to exert harmful biologic effects during pregnancy. The objective of present investigation is to measure the vaginal electrical resistance (VER) in LPS-treated normal cycling and pregnant female mice., Method of Study: Minimum dose (MD) of LPS (250 microg/kg body weight) was injected in pregnant female mice through i.p. route on day 0.5 of pregnancy. VER was measured during different phases of reproductive cycle in female mice, which were pre-exposed to LPS and in untreated cycling female mice. VER was also measured in control pregnant female mice (saline-treated mice) through whole pregnancy and LPS-treated female mice in early stages of pregnancy., Results: Vaginal electrical resistance was significantly higher during proestrous or early estrous stage as compared with any other stages of reproductive cycle in mouse. One peak of VER was observed during peri-implantation period of pregnancy in control female mice. The significant differences in the pattern of VER were found between LPS-treated and control female mice during peri-implantation period of pregnancy, and between cycling female mice, which were pre-exposed to LPS and untreated cycling female mice during proestrus., Conclusion: The presented results demonstrate, for the first time, that LPS exposure during pregnancy may be determined by measuring VER in mothers without any adverse effect on ongoing pregnancy and may help in refining the assisted reproduction techniques.

Because the phosphatidylinositol-3-kinase-AKT pathway is emerging as an important regulator of tumor cell survival, inhibitors of this pathway have enormous potential in cancer treatment. A specific inhibitor of AKT, [d-3-deoxy-2-O-methyl-myo-inositol-1-[(R)-2-methoxy-3-(octadecyloxy)propyl hydrogen phosphate]] (SH-5) has been recently synthesized, but little is known about its effects on cytokine signaling. We found that SH-5 potentiated the apoptosis induced by tumor necrosis factor (TNF), as indicated by intracellular esterase staining, annexin V staining, and caspase-3 activation. This effect of SH-5 correlated with downregulation of various gene products that mediate cell survival, proliferation, metastasis, and invasion, all known to be regulated by NF-kappaB. SH-5 also blocked NF-kappaB activation induced by TNF-alpha, lipopolysaccharide, phorbol ester, and cigarette smoke but not that activated by hydrogen peroxide and RANK ligand, indicating differential requirement of AKT. Inhibition of NF-kappaB correlated with abrogation of phosphorylation and degradation of IkappaBalpha through the inhibition of activation of IkappaBalpha kinase (IKK). This led to suppression of the phosphorylation and translocation of p65 and also of NF-kappaB reporter activity induced by TNFR1, TRADD, TRAF2, NIK, and IKKbeta but not that induced by p65 transfection. Thus, our results clearly demonstrate that inhibition of AKT leads to potentiation of apoptosis through modulation of NF-kappaB signaling.

Simvastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, is a cholesterol-lowering drug that may play a role in bone metabolism through a mechanism that is not fully understood. Recently, receptor activator of NF-kappaB ligand (RANKL), a member of the TNF superfamily, has emerged as a major mediator of bone loss via activation of osteoclastogenesis. The latter is also associated with certain cancers such as multiple myeloma and breast cancer. Whether simvastatin can modulate RANKL-induced or cancer induced osteoclastogenesis was investigated. The effect of simvastatin on RANKL signaling and consequent osteoclastogenesis was investigated. RANKL induced NF-kappaB activation, whereas pretreatment with simvastatin completely suppressed such activation and correlated with suppression of RANKL-induced activation of IkappaBalpha kinase, IkappaBalpha phosphorylation and IkappaBalpha degradation. Similarly, RANKL induced the differentiation of monocytic cells to osteoclasts, whereas simvastatin suppressed it. The inhibition was maximal when cells were exposed to both simvastatin and RANKL simultaneously and minimal when simvastatin was added 1 day after RANKL treatment. Simvastatin also inhibited the osteoclastogenesis induced by human breast cancer and by multiple myeloma cells. Together, our results indicate that simvastatin inhibits the RANKL-induced NF-kappaB activation pathway that leads to suppression of osteoclastogenesis induced by RANKL and by tumor cells, thereby suggesting its therapeutic potential in osteoporosis and in cancer-related bone loss.

Berberine, an isoquinoline alkaloid derived from a plant used traditionally in Chinese and Ayurvedic medicine, has been reported to exhibit chemopreventive and anti-inflammatory activities through unknown mechanism. Because of the critical role of the transcription factor nuclear factor-kappaB (NF-kappaB) in these processes, we investigated the effect of berberine on this pathway. We found that berberine suppressed NF-kappaB activation induced by various inflammatory agents and carcinogens. This alkaloid also suppressed constitutive NF-kappaB activation found in certain tumor cells. Suppression of NF-kappaB activation occurred through the inhibition of phosphorylation and degradation of IkappaBalpha by the inhibition of IkappaB kinase (IKK) activation, leading to suppression of phosphorylation and nuclear translocation of p65, and finally to inhibition of NF-kappaB reporter activity. Inhibition of IKK by berbeine was direct and could be reversed by reducing agents. Site-specific mutagenesis suggested the involvement of cysteine residue 179 in IKK. Berberine also suppressed the expression of NF-kappaB-regulated gene products involved in antiapoptosis (Bcl-xL, Survivin, IAP1, IAP2, and cFLIP), proliferation (cyclin D1), inflammation (cyclooxygenase-2), and invasion (matrix metalloproteinase-9). Suppression of antiapoptotic gene products correlated with enhancement of apoptosis induced by tumor necrosis factor (TNF)-alpha and chemotherapeutic agents and with inhibition of TNF-induced cellular invasion. Overall, our results indicate that chemopreventive, apoptotic, and anti-inflammatory activities displayed by berberine may be mediated in part through the suppression of the NF-kappaB activation pathway. This may provide the molecular basis for the ability of berberine to act as an anticancer and anti-inflammatory agent.

Anacardic acid (6-pentadecylsalicylic acid) is derived from traditional medicinal plants, such as cashew nuts, and has been linked to anticancer, anti-inflammatory, and radiosensitization activities through a mechanism that is not yet fully understood. Because of the role of nuclear factor-kappaB (NF-kappaB) activation in these cellular responses, we postulated that anacardic acid might interfere with this pathway. We found that this salicylic acid potentiated the apoptosis induced by cytokine and chemotherapeutic agents, which correlated with the down-regulation of various gene products that mediate proliferation (cyclin D1 and cyclooxygenase-2), survival (Bcl-2, Bcl-xL, cFLIP, cIAP-1, and survivin), invasion (matrix metalloproteinase-9 and intercellular adhesion molecule-1), and angiogenesis (vascular endothelial growth factor), all known to be regulated by the NF-kappaB. We found that anacardic acid inhibited both inducible and constitutive NF-kappaB activation; suppressed the activation of IkappaBalpha kinase that led to abrogation of phosphorylation and degradation of IkappaBalpha; inhibited acetylation and nuclear translocation of p65; and suppressed NF-kappaB-dependent reporter gene expression. Down-regulation of the p300 histone acetyltransferase gene by RNA interference abrogated the effect of anacardic acid on NF-kappaB suppression, suggesting the critical role of this enzyme. Overall, our results demonstrate a novel role for anacardic acid in potentially preventing or treating cancer through modulation of NF-kappaB signaling pathway.

3,4-dihydroxybenzalacetone (DBL) is a polyphenol derived from the medicinal plant Chaga [Inonotus obliquus (persoon) Pilat]. Although Chaga is used in Russia folk medicine to treat tumors, very little is known about its mechanism of action. Because most genes involved in inflammation, antiapoptosis, and cell proliferation are regulated by the transcription factor nuclear factor-kappaB (NF-kappaB), we postulated that DBL activity is mediated via modulation of the NF-kappaB activation pathway. We investigated the effects of DBL on NF-kappaB activation by electrophoretic mobility shift assay and on NF-kappaB-regulated gene expression by Western blot analysis. We found that DBL suppressed NF-kappaB activation by a wide variety of inflammatory agents, including tumor necrosis factor (TNF), interleukin-1beta, epidermal growth factor, okadaic acid, phorbol 12-myristate 13-acetate, and lipopolysaccharide. The suppression was not cell type specific and inhibited both inducible and constitutive NF-kappaB activation. DBL did not interfere with the binding of NF-kappaB to DNA but rather inhibited IkappaBalpha kinase activity, IkappaBalpha phosphorylation and degradation, p65 phosphorylation, and translocation. DBL also suppressed the expression of TNF-induced and NF-kappaB-regulated proliferative, antiapoptotic, and metastatic gene products. These effects correlated with enhancement of TNF-induced apoptosis and suppression of TNF-induced invasion. Together, our results indicate that DBL inhibits NF-kappaB activation and NF-kappaB-regulated gene expression, which may explain the ability of DBL to enhance apoptosis and inhibit invasion.

Gambogic acid (GA), a xanthone derived from the resin of the Garcinia hanburyi, has been recently demonstrated to bind transferrin receptor and exhibit potential anticancer effects through a signaling mechanism that is not fully understood. Because of the critical role of NF-kappaB signaling pathway, we investigated the effects of GA on NF-kappaB-mediated cellular responses and NF-kappaB-regulated gene products in human leukemia cancer cells. Treatment of cells with GA enhanced apoptosis induced by tumor necrosis factor (TNF) and chemotherapeutic agents, inhibited the expression of gene products involved in antiapoptosis (IAP1 and IAP2, Bcl-2, Bcl-x(L), and TRAF1), proliferation (cyclin D1 and c-Myc), invasion (COX-2 and MMP-9), and angiogenesis (VEGF), all of which are known to be regulated by NF-kappaB. GA suppressed NF-kappaB activation induced by various inflammatory agents and carcinogens and this, accompanied by the inhibition of TAK1/TAB1-mediated IKK activation, inhibited IkappaBalpha phosphorylation and degradation, suppressed p65 phosphorylation and nuclear translocation, and finally abrogated NF-kappaB-dependent reporter gene expression. The NF-kappaB activation induced by TNFR1, TRADD, TRAF2, NIK, TAK1/TAB1, and IKKbeta was also inhibited. The effect of GA mediated through transferrin receptor as down-regulation of the receptor by RNA interference reversed its effects on NF-kappaB and apoptosis. Overall our results demonstrate that GA inhibits NF-kappaB signaling pathway and potentiates apoptosis through its interaction with the transferrin receptor.

Overexpression of epidermal growth factor (EGF) receptor and constitutive activation of nuclear factor-kappaB (NF-kappaB) are frequently encountered in tumor cells. Although EGF has been shown to induce NF-kappaB activation, the mechanism is poorly understood. EGF activated NF-kappaB DNA binding, induced NF-kappaB reporter activity and the expression of antiapoptotic and cell-proliferative gene products. Interestingly, non-small cell lung adenocarcinoma cell lines (HCC827 and H3255), which exhibit EGFR amplification, showed ligand-independent activation of NF-kappaB. Unlike tumor-necrosis factor (TNF), however, EGF failed to induce IkappaBalpha phosphorylation and ubiquitination and the activation of IkappaBalpha kinase (IKK). Although DN-IKKbeta inhibited TNF-induced NF-kappaB activity, DN-IKKbeta had no effect on EGF-induced NF-kappaB activation, suggesting that EGF-induced NF-kappaB activation is IKK independent. Using dominant-negative plasmids, we also demonstrated the role of TRADD, TRAF2, NIK and Ras in EGF-induced NF-kappaB activation. By using specific antibodies and IkappaBalpha plasmid, which is mutated at tyrosine 42 to phenylalanine, we show that EGF induced the tyrosine phosphorylation of IkappaBalpha at residue 42. Furthermore, EGF receptor kinase inhibitor blocked IkappaBalpha phosphorylation and consequent NF-kappaB activation. Overall, our results indicate that tyrosine phosphorylation of IkappaBalpha at residue 42 is critical for EGF-induced NF-kappaB activation pathway.

NRH:quinone oxidoreductase 2 (NQO2) is a cytosolic flavoprotein that catalyzes the two-electron reduction of quinones and quinoid compounds to hydroquinones. Although the role of a homologue, NAD(P)H:quinone oxidoreductase 1 (NQO1), is well defined in oxidative stress, neoplasia, and carcinogenesis, little is known about the mechanism of actions of NQO2 in these cellular responses. Whether NQO2 has any role in tumor necrosis factor (TNF) signaling was investigated using keratinocytes derived from wild-type and NQO2 knockout (NQO2-/-) mice. Although exposure of wild-type cells to TNF led to activation of nuclear factor-kappaB (NF-kappaB) and IkappaBalpha kinase, IkappaBalpha degradation, p65 phosphorylation, and p65 nuclear translocation, this cytokine had no effect on NQO2-/- cells. Deletion of NQO2 also abolished TNF-induced c-Jun NH2-terminal kinase, Akt, p38, and p44/p42 mitogen-activated protein kinase activation. The induction of various antiapoptotic gene products (MMP-9, cyclin D1, COX-2, IAP1, IAP2, Bcl-2, cFLIP, and XIAP) by TNF was also abolished in NQO2-/- cells. This correlated with potentiation of TNF-induced apoptosis as indicated by cell viability, Annexin V staining, and caspase activation. In agreement with this, we also found that TNF activated NQO2, and NQO2-specific small interfering RNA abrogated the TNF-induced NQO2 activity and NF-kappaB activation. Overall, our results indicate that deletion of NQO2 plays a differential role in TNF signaling pathway: by suppressing cell survival signals and potentiating TNF-induced apoptosis.

Almost 19 members of the tumor necrosis factor (TNF) superfamily have been identified that interact with 29 different receptors. Whether these receptors communicate with each other is not understood. Recently, we have shown that receptor activator of NF-kappaB ligand signaling is modulated by genetic deletion of the TNF receptor. In the current report, we investigated the possibility of a cross-talk between Fas and TNF-alpha signaling pathway in macrophage cell lines derived from wild-type (WT) mice and from mice with genetic deletion of the type 1 TNF receptor (p60(-/-)), the type 2 TNF receptor (p80(-/-)), or both receptors (p60(-/-)p80(-/-)). We found that the macrophages expressing TNF receptors were highly sensitive to apoptosis induced by anti-Fas. The genetic deletion of TNF receptors, however, made the cells resistance to anti-Fas-induced apoptosis. Anti-Fas induced activation of caspase-3 and PARP cleavage in WT cells but not in TNF receptor-deleted cells. This difference was found to be independent of the expression of Fas, Fas-associated protein with death domain (FADD) or TNF receptor-associated death domain (TRADD). We found that anti-Fas induced recruitment of TNFR1 into Fas-complex. We also found that TRADD, which mediates TNF signaling, was constitutively bound to Fas receptor in TNF receptor-deleted cells but not in wild-type cells. Transient transfection of TNFR1 in TNFR1-deleted cells sensitized them to anti-Fas-induced apoptosis. Overall our results demonstrate that Fas signaling is modulated by the TNF receptors and thus provide the evidence of cross-talk between the receptors of two cytokines.

Salinosporamide A (also called NPI-0052), recently identified from the marine bacterium Salinispora tropica, is a potent inhibitor of 20S proteasome and exhibits therapeutic potential against a wide variety of tumors through a poorly understood mechanism. Here we demonstrate that salinosporamide A potentiated the apoptosis induced by tumor necrosis factor alpha (TNF), bortezomib, and thalidomide, and this correlated with down-regulation of gene products that mediate cell proliferation (cyclin D1, cyclooxygenase-2 [COX-2], and c-Myc), cell survival (Bcl-2, Bcl-xL, cFLIP, TRAF1, IAP1, IAP2, and survivin), invasion (matrix metallopro-teinase-9 [MMP-9] and ICAM-1), and angiogenesis (vascular endothelial growth factor [VEGF]). Salinosporamide A also suppressed TNF-induced tumor cell invasion and receptor activator of nuclear factor kappaB ligand (RANKL)-induced osteoclastogenesis. We also found that it suppressed both constitutive and inducible NF-kappaB activation. Compared with bortezomib, MG-132, N-acetyl-leucyl-leucyl-norleucinal (ALLN), and lactacystin, salinosporamide A was found to be the most potent suppressor of NF-kappaB activation. Further studies showed that salinosporamide A inhibited TNF-induced inhibitory subunit of NF-kappaB alpha (IkappaBalpha) degradation, nuclear translocation of p65, and NF-kappaB-dependent reporter gene expression but had no effect on IkappaBalpha kinase activation, IkappaBalpha phosphorylation, or IkappaBalpha ubiquitination. Thus, overall, our results indicate that salinosporamide A enhances apoptosis, suppresses osteoclastogenesis, and inhibits invasion through suppression of the NF-kappaB pathway.

Constitutively activated nuclear factor-kappaB (NF-kappaB) has been associated with a variety of aggressive tumor types, including head and neck squamous cell carcinoma (HNSCC); however, the mechanism of its activation is not fully understood. Therefore, we investigated the molecular pathway that mediates constitutive activation of NF-kappaB in a series of HNSCC cell lines. We confirmed that NF-kappaB was constitutively active in all HNSCC cell lines (FaDu, LICR-LON-HN5 and SCC4) examined as indicated by DNA binding, immunocytochemical localization of p65, by NF-kappaB-dependent reporter gene expression and its inhibition by dominant-negative (DN)-inhibitory subunit of NF-kappaB (IkappaBalpha), the natural inhibitor of NF-kappaB. Constitutive NF-kappaB activation in HNSCC was found to be due to constitutive activation of IkappaBalpha kinase (IKK); and this correlated with constitutive expression of phosphorylated forms of IkappaBalpha and p65 proteins. All HNSCC showed the expression of p50, p52, p100 and receptor-interacting protein; all linked with NF-kappaB activation. The expression of constitutively active NF-kappaB in HNSCC is mediated through the tumor necrosis factor (TNF) signaling pathway, as NF-kappaB reporter activity was inhibited by DN-TNF receptor-associated death domain (TRADD), DN-TNF receptor-associated factor (TRAF)2, DN-receptor-interacting protein (RIP), DN-transforming growth factor-beta-activated kinase 1 (TAK1), DN-kappa-Ras, DN-AKT and DN-IKK but not by DN-TRAF5 or DN-TRAF6. Constitutive NF-kappaB activation was also associated with the autocrine expression of TNF, TNF receptors and receptor-activator of NF-kappaB and its ligand in HNSCC cells but not interleukin (IL)-1beta. All HNSCC cell lines expressed IL-6, a NF-kappaB-regulated gene product. Furthermore, treatment of HNSCC cells with anti-TNF antibody downregulated constitutively active NF-kappaB, and this was associated with inhibition of IL-6 expression and cell proliferation. Our results clearly demonstrate that constitutive activation of NF-kappaB is mediated through the TRADD-TRAF2-RIP-TAK1-IKK pathway, making TNF a novel target in the treatment of head and neck cancer.

Curcumin is the active ingredient of turmeric that has been consumed as a dietary spice for ages. Turmeric is widely used in traditional Indian medicine to cure biliary disorders, anorexia, cough, diabetic wounds, hepatic disorders, rheumatism, and sinusitis. Extensive investigation over the last five decades has indicated that curcumin reduces blood cholesterol, prevents low-density lipoprotein oxidation, inhibits platelet aggregation, suppresses thrombosis and myocardial infarction, suppresses symptoms associated with type II diabetes, rheumatoid arthritis, multiple sclerosis, and Alzheimer's disease, inhibits HIV replication, enhances wound healing, protects from liver injury, increases bile secretion, protects from cataract formation, and protects from pulmonary toxicity and fibrosis. Evidence indicates that the divergent effects of curcumin are dependent on its pleiotropic molecular effects. These include the regulation of signal transduction pathways and direct modulation of several enzymatic activities. Most of these signaling cascades lead to the activation of transcription factors. Curcumin has been found to modulate the activity of several key transcription factors and, in turn, the cellular expression profiles. Curcumin has been shown to elicit vital cellular responses such as cell cycle arrest, apoptosis, and differentiation by activating a cascade of molecular events. In this chapter, we briefly review the effects of curcumin on transcription factors NF-KB, AP-1, Egr-1, STATs, PPAR-gamma, beta-catenin, nrf2, EpRE, p53, CBP, and androgen receptor (AR) and AR-related cofactors giving major emphasis to the molecular mechanisms of its action.

Although indirubin is known to exhibit anti-cancer and anti-inflammatory activities, very little is known about its mechanism of action. In this study, we investigated whether indirubin mediates its effects through interference with the NF-kappaB pathway. As examined by the DNA binding of NF-kappaB, we found that indirubin suppressed tumor necrosis factor (TNF)-induced NF-kappaB activation in a dose- and time-dependent manner. Indirubin also suppressed the NF-kappaB activation induced by various inflammatory agents and carcinogens. Further studies showed that indirubin blocked the phosphorylation and degradation of IkappaB alpha through the inhibition of activation of IkappaB alpha kinase and phosphorylation and nuclear translocation of p65. NF-kappaB reporter activity induced by TNFR1, TNF receptor-associated death domain, TRAF2, TAK1, NF-kappaB-inducing kinase, and IKKbeta was inhibited by indirubin but not that induced by p65 transfection. We also found that indirubin inhibited the expression of NF-kappaB-regulated gene products involved in antiapoptosis (IAP1, IAP2, Bcl-2, Bcl-xL, and TRAF1), proliferation (cyclin D1 and c-Myc), and invasion (COX-2 and MMP-9). This correlated with enhancement of the apoptosis induced by TNF and the chemotherapeutic agent taxol in human leukemic KBM-5 cells. Indirubin also suppressed cytokine-induced cellular invasion. Overall, our results indicate that anti-cancer and anti-inflammatory activities previously assigned to indirubin may be mediated in part through the suppression of the NF-kappaB activation pathway.

Mammalian embryonic development is regulated by several cytokines and growth factors from embryonic or maternal origins. Since CSF-1 plays important role in embryonic development and implantation, we investigated its role in gram-negative bacterial LPS-induced implantation failure. The effect of LPS on normal (nonsuperovulated) and superovulated in vivo-produced embryos was assessed by signs of morphological degeneration. A significantly similar number of morphologically degenerated embryos recovered from both nonsuperovulated and superovulated LPS treated animals on day 2.5 of pregnancy onwards were morphologically and developmentally abnormal as compared to their respective controls (P < .001. Normal CSF-1 expression level and pattern were also altered through the preimplantation period in the mouse embryos and uterine horns after LPS treatment. This deviation from the normal pattern and level of CSF-1 expression in the preimplantation embryos and uterine tissues suggest a role for CSF-1 in LPS-induced implantation failure.

Genito-urinary tract or systemic infections of the gram-negative bacteria in pregnant women, causes abortions, preterm labor, and several other perinatal complications. LPS is the most potent antigenic component of the gram-negative bacterial cell wall and is known to modulate the expression of various proinflammatory cytokines. Here we investigate the role of the soluble form of IL-1 i.e., IL-1beta in the 'minimum dose' of LPS induced pregnancy loss in mice. Uterine cross-sections on each day of the preimplantation period of pregnancy were examined histopathologically for finding out LPS induced changes in the uterine preparation for embryo implantation. The expression of IL-1beta in the various stages of the preimplantation period of pregnancy was studied by RT-PCR in the embryos and the uterine horns of the LPS treated and normal pregnant mice. We found that LPS significantly alters the proliferation of the glandular epithelium, luminal epithelium and stroma during the preimplantation period. We also found large infiltration of macrophages into the uterine horns of the LPS treated animals. The level and pattern of IL-1beta expression in the preimplantation embryos and uterine horns were also altered in LPS treated animals. These observations indicate that LPS can alter the uterine preparation for blastocyst implantation, which could be due to the change in the IL-1beta expression in the uterine horns. However, a change in the expression pattern of IL-1beta in the preimplantation embryos underlines the significance of this molecule in LPS induced pregnancy loss or implantation failure in mouse.

Background and aims:  Gram-negative bacterial lipopolysaccharides (LPS) are known causative agents for pregnancy loss in mothers with genital tract infections. In this study, we attempt to test the role of tumor necrosis factor-α (TNF-α) in the normal physiological processes of preimplantation embryonic development and LPS induced pregnancy loss in mice. Since the preimplantation mouse embryos grow in an unattached state for a considerable period (day 1-4.5) of its development in the maternal environment, it is possible that a critical level of soluble and biologically active TNF-α is maintained in the maternal environment, and that any alteration in this could lead to implantation failure. Here we determine the pattern and level of expression of TNF-α gene in preimplantation stage embryos and uterus collected from control and LPS treated pregnant animals during different stages of preimplantation period of pregnancy by reverse transcriptase-polymerase chain reaction. Methods:  The concentrations and biological activity of soluble TNF-α protein present in oviductal fluid (OF) and uterine fluid (UF), in the normal and LPS treated animals, were determined by enzyme-linked immunosorbent assay and 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide assay on L929 cells, respectively. TNF-α was also given i.p. to study its effect on implantation. Results:  An early expression of TNF-α messenger ribonucleic acid in the preimplantation stage embryos collected from LPS treated animals was observed along with a significant rise in the level of biologically active soluble TNF-α in the OF. Similarly, the level of bioactive and soluble TNF-α present in the UF from LPS treated animals was significantly higher as compared to the control on day 4.42 of pregnancy. Conclusions:  TNF-α given i.p. exerted similar effects on pregnancy as that of LPS. An incessant exposure of the preimplantation stage embryos to significantly high levels of maternal bioactive free/soluble TNF-α, and an alteration in the normal pattern of its expression in the preimplantation stage embryos may be one of the causes of failure of implantation leading to poor pregnancy outcome in LPS treated mouse. (Reprod Med Biol 2005; 4 : 79- 89).

Introduction: Intrauterine infection is frequently associated with pregnancy loss in pregnant women., Discussion: This article reviews the role of Gram-negative bacterial infection in various complications related to early pregnancy and subsequent pregnancy loss. Here we discuss the pathways of ascending intrauterine infection, microbiology and the pathophysiology of such infections. The clinical impact, therapy, consequences, prevention and implications of Gram-negative bacterial infections in women during their reproductive life span is also discussed. This article also makes an attempt to discuss our studies and findings, related to the effect of the LPS component of the Gram-negative bacterial endotoxin on preimplantation stage embryonic development and implantation. This early phase of pregnancy remains mostly unnoticed by the mother as well as the health care provider, and therefore holds more threat to the life of the fetus and the mother. The molecular mechanisms of LPS-induced pregnancy losses through abnormal embryonic development, implantation failure, and preterm labor and birth with specific references to the role of proinflammatory cytokines like IL-1 and TNF are discussed., Conclusion: Once these inflammatory mediators have increased in the feto-maternal tissues, it may be too late or harmful to try and prevent the adverse outcomes of pregnancy.

Genital tract infections caused by gram-negative bacteria induce abortion and are one of the most common complications of human pregnancy. This study was carried out to decipher the mechanism of gram-negative bacterial lipopolysaccharide (LPS)-induced pregnancy loss, using a mouse (Park strain) model. Since many of the biological effects of LPS are mediated by interleukin (IL)-1alpha, the role of IL-1alpha in LPS-induced pregnancy loss was studied. Pregnant female animals were injected intra-peritoneally (i.p.) with different doses (1 to 50 microg) of LPS from Salmonella minnesota Re-595, on day 0.5 of pregnancy. We found that 250 microg/kg body weight (i.e. 5 microg/female mouse) of LPS when given on day 0.5 of pregnancy was the 'minimum dose' (MD) required to completely inhibit the implantation of the blastocyst in the mouse. The effect of this dose on the pathophysiology of the various reproductive organs (i.e. uterus, ectoplacental cones, developing fetus, ovaries etc.) was assessed on day 14 of pregnancy. The effects of this dose on the level and pattern of expression of the proinflammatory cytokine IL-1alpha in the maternal uterine horns and preimplantation stage embryos were studied by RT-PCR. A single dose (100 ng/mouse) of recombinant mouse IL-1alpha was given i.p. to pregnant females on day 1 of pregnancy to study its effect on implantation. Our results show that treatment of the pregnant animals with LPS may alter cell proliferation and induce leukocyte infiltration, degeneration of luminal glandular epithelium, and hyperplasia in the various reproductive organs, and may also alter both embryonic and uterine IL-1alpha expression. IL-1alpha administration also caused implantation failure similar to that of LPS. The observations suggest that the determined MD of LPS may alter the expression of developmentally important proinflammatory cytokines such as IL-1alpha, which could, in turn, inhibit the normal processes of blastocyst implantation. Therefore, it is proposed that the LPS-induced histopathological alterations in the various reproductive organs of pregnant animals could be mediated by IL-1alpha and this may be one of the causes of failure of blastocyst implantation in the mouse.

We had recently characterized SLC, a SWI/SNF-like chromatin remodelling activity, from chicken liver. The SLC efficiently disrupts nucleosomes, transfers histone octamers from nucleosomal substrates onto acceptor DNA, and slides histone octamers along DNA. Here, we present evidence that SLC is indeed a SWI/SNF homologue, and it disrupts nucleosomes by inducing extensive dynamic helical distortions in the nucleosomal DNA. Both the nucleosome disruption and octamer transfer functions are indifferent to nucleosomal histone tails. We further show that the nucleosome disruption precedes the octamer transfer and that the latter requires continuous presence of ATP. Based on these observations, we propose that a disrupted nucleosome is not a spontaneous substrate for octamer transfer; rather the nucleosome disruption and the octamer transfer are two temporally successive, ATP-dependent events during nucleosome remodelling by SLC in vitro.

ATP-dependent chromatin remodeling factors have been implicated in nuclear processes involving DNA. Here we report partial purification and characterization of an ATP-dependent chromatin remodeling activity from chicken liver. Nuclear extract from chicken liver was fractionated chromatographically to enrich proteins immunoreacting to antibodies against components of human SWI/SNF, namely BRG1, BAF170, BAF155, and BAF57. Immunoreactivity to these antibodies elutes with a mass of about 2MDa on Sepharose CL-6B gel filtration, suggesting that they constitute a SWI/SNF-like complex (SLC). The SLC displays three chromatin-remodeling activities, viz. nucleosome disruption, octamer transfer, and nucleosome sliding (octamer transfer in cis). We further show that components of SLC, as revealed by immunoreactivity to the above antibodies, display a dynamic nucleocytoplasmic distribution and colocalize with RNA polymerase II in the liver nuclei. This report contributes to the understanding of phylogenetic generality of chromatin remodeling factors in eukaryotes.

Anethole, a chief constituent of anise, camphor, and fennel, has been shown to block both inflammation and carcinogenesis, but just how these effects are mediated is not known. One possibility is TNF-mediated signaling, which has also been associated with both inflammation and carcinogenesis. In the present report we show that anethole is a potent inhibitor of TNF-induced NF-kappaB activation (an early response) as monitored by electrophoretic mobility shift assay, IkappaBalpha phosphorylation and degradation, and NF-kappaB reporter gene expression. Suppression of IkappaBalpha phosphorylation and NF-kappaB reporter gene expression induced by TRAF2 and NIK, suggests that anethole acts on IkappaBalpha kinase. Anethole also blocked the NF-kappaB activation induced by a variety of other inflammatory agents. Besides NF-kappaB, anethole also suppressed TNF-induced activation of the transcription factor AP-1, c-jun N-terminal kinase and MAPK-kinase. In addition, anethole abrogated TNF-induced apoptosis as measured by both caspase activation and cell viability. The anethole analogues eugenol and isoeugenol also blocked TNF signaling. Anethole suppressed TNF-induced both lipid peroxidation and ROI generation. Overall, our results demonstrate that anethole inhibits TNF-induced cellular responses, which may explain its role in suppression of inflammation and carcinogenesis. Oncogene (2000).