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1.
FASEB J ; 36(1): e22090, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34907595

RESUMO

Despite many advances in infection control practices, including prophylactic antibiotics, surgical site infections (SSIs) remain a significant cause of morbidity, prolonged hospitalization, and death worldwide. Our innate immune system possesses a multitude of powerful antimicrobial strategies which make it highly effective in combating bacterial, fungal, and viral infections. However, pathogens use various stealth mechanisms to avoid the innate immune system, which in turn buy them time to colonize wounds and damage tissues at surgical sites. We hypothesized that immunomodulators that can jumpstart and activate innate immune responses at surgical sites, would likely reduce infection at surgical sites. We used three immunomodulators; fMLP (formyl-Methionine-Lysine-Proline), CCL3 (MIP-1α), and LPS (Lipopolysaccharide), based on their documented ability to elicit strong inflammatory responses; in a surgical wound infection model with Pseudomonas aeruginosa to evaluate our hypothesis. Our data indicate that one-time topical treatment with these immunomodulators at low doses significantly increased proinflammatory responses in infected and uninfected surgical wounds and were as effective, (or even better), than a potent prophylactic antibiotic (Tobramycin) in reducing P. aeruginosa infection in wounds. Our data further show that immunomodulators did not have adverse effects on tissue repair and wound healing processes. Rather, they enhanced healing in both infected and uninfected wounds. Collectively, our data demonstrate that harnessing the power of the innate immune system by immunomodulators can significantly boost infection control and potentially stimulate healing. We propose that topical treatment with these immunomodulators at the time of surgery may have therapeutic potential in combating SSI, alone or in combination with prophylactic antibiotics.


Assuntos
Fatores Imunológicos/farmacologia , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/imunologia , Infecção da Ferida Cirúrgica/tratamento farmacológico , Animais , Avaliação de Medicamentos , Camundongos , Camundongos Knockout , Infecções por Pseudomonas/imunologia , Infecção da Ferida Cirúrgica/imunologia , Infecção da Ferida Cirúrgica/microbiologia
2.
Cell Microbiol ; 23(8): e13339, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33821556

RESUMO

Recently, we demonstrated that Pseudomonas aeruginosa Exotoxin T (ExoT) employs two distinct mechanisms to induce potent apoptotic cytotoxicity in a variety of cancer cell lines. We further demonstrated that it can significantly reduce tumour growth in an animal model for melanoma. During these studies, we observed that melanoma cells that were transfected with ExoT failed to undergo mitosis, regardless of whether they eventually succumbed to ExoT-induced apoptosis or survived in ExoT's presence. In this report, we sought to investigate ExoT's antiproliferative activity in melanoma. We delivered ExoT into B16 melanoma cells by bacteria (to show necessity) and by transfection (to show sufficiency). Our data indicate that ExoT exerts a potent antiproliferative function in melanoma cells. We show that ExoT causes cell cycle arrest in G1 interphase in melanoma cells by dampening the G1/S checkpoint proteins. Our data demonstrate that both domains of ExoT; (the ADP-ribosyltransferase (ADPRT) domain and the GTPase activating protein (GAP) domain); contribute to ExoT-induced G1 cell cycle arrest in melanoma. Finally, we show that the ADPRT-induced G1 cell cycle arrest in melanoma cells likely involves the Crk adaptor protein. Our data reveal a novel virulence function for ExoT and further highlight the therapeutic potential of ExoT against cancer.


Assuntos
Melanoma , Pseudomonas aeruginosa , ADP Ribose Transferases , Animais , Exotoxinas , Pontos de Checagem da Fase G1 do Ciclo Celular , Células HeLa , Humanos
3.
Mol Carcinog ; 58(6): 996-1007, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30720225

RESUMO

The overall promise of breast cancer chemoprevention is exemplified by clinical success of selective estrogen receptor modulators and aromatase inhibitors. Despite clinical efficacy, these interventions have limitations, including rare but serious side effects and lack of activity against estrogen receptor-negative breast cancers. We have shown previously that dietary administration of benzyl isothiocyanate (BITC), which occurs naturally as a thioglucoside conjugate in edible cruciferous vegetables, inhibits development of estrogen receptor-negative breast cancer in mouse mammary tumor virus-neu (MMTV-neu) transgenic mice. This study demonstrates AKT-mediated sugar addiction in breast cancer chemoprevention by BITC. BITC-treated MMTV-neu mice exhibited increased 2-deoxy-2-(18 F)-fluoro-D-glucose (18 F-FDG) uptake in mammary tumors in vivo in comparison with mice fed basal diet. Cellular studies using MDA-MB-231 and SUM159 human breast cancer cell lines revealed BITC-mediated induction and punctate localization of glucose transporter GLUT-1, which was accompanied by an increase in intracellular pyruvate levels. BITC treatment resulted in increased S473 phosphorylation (activation) of AKT in cells in vitro as well as in mammary tumors of MMTV-neu mice in vivo. Increased glucose uptake, punctate pattern of GLUT-1 localization, and intracellular pyruvate levels resulting from BITC exposure were significantly attenuated in the presence of a pharmacological inhibitor of AKT (MK-2206). Inhibition of AKT augmented BITC-mediated inhibition of cell migration and colony formation. BITC-induced apoptotic cell death was also increased by pharmacological inhibition of AKT. These results indicate increased glucose uptake/metabolism by BITC treatment in breast cancer cells suggesting that breast cancer chemoprevention by BITC may be augmented by pharmacological inhibition of AKT.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Fluordesoxiglucose F18/metabolismo , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Isotiocianatos/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Transportador de Glucose Tipo 1/metabolismo , Compostos Heterocíclicos com 3 Anéis/farmacologia , Humanos , Isotiocianatos/farmacologia , Camundongos , Fosforilação/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Semin Cancer Biol ; 47: 147-153, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-27867044

RESUMO

Cancer chemoprevention, a scientific term coined by Dr. Sporn in the late seventies, implies use of natural or synthetic chemicals to block, delay or reverse carcinogenesis. Phytochemicals derived from edible and medicinal plants have been studied rather extensively for cancer chemoprevention using preclinical models in the past few decades. Nevertheless, some of these agents (e.g., isothiocyanates from cruciferous vegetables like broccoli and watercress) have already entered into clinical investigations. Examples of widely studied and highly promising phytochemicals from edible and medicinal plants include cruciferous vegetable constituents (phenethyl isothiocyanate, benzyl isothiocyanate, and sulforaphane), withaferin A (WA) derived from a medicinal plant (Withania somnifera) used heavily in Asia, and an oriental medicine plant component honokiol (HNK). An interesting feature of these structurally-diverse phytochemicals is that they target mitochondria to provoke cancer cell-selective death program. Mechanisms underlying cell death induction by commonly studied phytochemicals have been discussed rather extensively and thus are not covered in this review article. Instead, the primary focus of this perspective is to discuss experimental evidence pointing to mitochondrial dysfunction in cancer chemoprevention by promising phytochemicals.


Assuntos
Quimioprevenção , Suplementos Nutricionais , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Neoplasias/prevenção & controle , Compostos Fitoquímicos/administração & dosagem , Plantas Medicinais/química , Animais , Complexo de Proteínas da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Humanos , Mitocôndrias/genética , Dinâmica Mitocondrial/efeitos dos fármacos
5.
Int Immunol ; 26(3): 159-72, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24225181

RESUMO

Zinc oxide nanoparticles (ZNPs) have been used in dietary supplements and may cause an immunomodulatory effect. The present study investigated the effect of ZNPs on antigen-specific immune responses in mice sensitized with the T-cell-dependent antigen ovalbumin (OVA). BALB/c mice were intraperitoneally administered ZNPs (0.25, 0.5, 1 and 3mg) once, in combination with OVA, and the serum antibodies, splenocyte reactivity and activation of antigen-presenting cells were examined. The serum levels of OVA-specific IgG1 and IgE were found significantly enhanced by treatment with ZNPs over control. An increased level of IL-2, IL-4, IL-6, IL-17 and decreased level of IL-10 and TNF-α in splenocytes administered with ZNPs were observed in comparison with control. The ZNPs and OVA-stimulated T lymphocytes showed enhanced proliferation compared with control. Macrophages and B cells showed high expression of MHC class II, whereas higher expression of CD11b in macrophages of the ZNPs and ZNPs/OVA treated groups was observed. The lungs and spleen had increased eosinophils and mast cell numbers. Also, myeloperoxidase activity in lungs was found to be increased by 2.5-fold in the case of ZNPs and 3.75-fold increase in ZNPs/OVA, whereas in intestine, there was significant increase in both the groups. Increased expression of the genes for GATA-3, SOCS-3, TLR-4, IL-13 and IL-5 in the intestine was observed. Collectively, these data indicate that systemic exposure to a single administration of ZNPs could enhance subsequent antigen-specific immune reactions, including the serum production of antigen-specific antibodies, and the functionality of T cells.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Linfócitos B/imunologia , Citocinas/biossíntese , Imunoglobulina E/biossíntese , Imunoglobulina G/biossíntese , Macrófagos/imunologia , Nanopartículas Metálicas/administração & dosagem , Células Th2/imunologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citocinas/sangue , Citocinas/genética , Suplementos Nutricionais/efeitos adversos , Feminino , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/genética , Imunoglobulina G/sangue , Imunoglobulina G/genética , Ativação Linfocitária/efeitos dos fármacos , Nanopartículas Metálicas/efeitos adversos , Nanopartículas Metálicas/química , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Regulação para Cima/efeitos dos fármacos , Óxido de Zinco/química
6.
Immunology ; 142(3): 453-64, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24593842

RESUMO

Macrophages are among the most sensitive immune cells because of their phagocytic activity and are prone to become dysfunctional or not able to perform properly if nanoparticle load increases. We have previously reported that zinc oxide nanoparticles (ZNPs) induce inflammatory responses in macrophages that contribute to their death. Recognition of ZNPs by pattern recognition receptors such as toll-like receptors (TLRs) might be a factor in the initiation of these responses in macrophages. Therefore, in this study we explored the role played by TLR6 and mitogen-activated protein kinase (MAPKs) pathways in the inflammatory responses of macrophages during ZNPs exposure. ZNPs-activated macrophages showed enhanced expression of activation and maturation markers (CD1d, MHC-II, CD86 and CD71). Among various TLRs screened, TLR6 emerged as the most potent activator for ZNPs-induced inflammatory responses. Downstream signalling proteins myeloid differentiation 88, interleukin-1 receptor associated kinase and tumour necrosis factor receptor-associated factor were also enhanced. On inhibiting MAPKs pathways individually, the inflammatory responses such as interleukin-1ß, interleukin-6, tumour necrosis factor-α, cyclooxygenase-2 and inducible nitric oxide synthase were suppressed. TLR6 silencing significantly inhibited the pro-inflammatory cytokine levels, reactive nitrogen species generation and inducible nitric oxide synthase expression. Also, inhibition of MAPKs in the absence of TLR6 signalling validated the link between TLR6 and MAPKs in ZNPs-induced inflammatory responses. TLR6 was found to be co-localized with autophagosomes. Macrophages lacking TLR6 inhibited the autophagosome marker protein-microtubule-associated protein1 light chain 3-isoform II formation and phagocytosis. These results demonstrate that inflammatory responses caused by ZNPs-activated macrophages strongly depend on TLR6-mediated MAPK signalling.


Assuntos
Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Nanopartículas/química , Receptor 6 Toll-Like/metabolismo , Óxido de Zinco/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade
7.
Cancers (Basel) ; 16(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38398170

RESUMO

The gut microbiota composition can affect the tumor microenvironment and its interaction with the immune system, thereby having implications for treatment predictions. This article reviews the studies available to better understand how the gut microbiome helps the immune system fight cancer. To describe this fact, different mechanisms and approaches utilizing probiotics to improve advancements in cancer treatment will be discussed. Moreover, not only calorie intake but also the variety and quality of diet can influence cancer patients' immunotherapy treatment because dietary patterns can impair immunological activities either by stimulating or suppressing innate and adaptive immunity. Therefore, it is interesting and critical to understand gut microbiome composition as a biomarker to predict cancer immunotherapy outcomes and responses. Here, more emphasis will be given to the recent development in immunotherapies utilizing microbiota to improve cancer therapies, which is beneficial for cancer patients.

8.
J Invest Dermatol ; 144(2): 387-397.e11, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37619833

RESUMO

Diabetic chronic ulcers are plagued with persistent nonresolving inflammation. However, diabetic wound environment early after injury suffers from inadequate inflammatory responses due to reductions in proinflammatory cytokines levels. Diabetic neutrophils have known impairments in bactericidal functions. We hypothesized that reduced bacterial killing by diabetic neutrophils, due to their bactericidal functional impairments, results in reduced bioactive bacterial products, known as pathogen-associated molecular patterns, which in turn contribute to reduced signaling through toll-like receptors, leading to inadequate production of proinflammatory cytokines in infected diabetic wound early after injury. We tested our hypothesis in db/db type 2 obese diabetic mouse wound infection model with Pseudomonas aeruginosa. Our data indicate that despite substantially higher levels of infection, toll-like receptor 4-mediated signaling is reduced in diabetic wounds early after injury owing to reduced bioactive levels of lipopolysaccharide. We further demonstrate that topical treatment with lipopolysaccharide enhances toll-like receptor 4 signaling, increases proinflammatory cytokine production, restores leukocyte trafficking, reduces infection burden, and stimulates healing in diabetic wounds. We posit that lipopolysaccharide may be a viable therapeutic option for the treatment of diabetic foot ulcers if it is applied topically after the surgical debridement process, which is intended to reset chronic ulcers into acute fresh wounds.


Assuntos
Diabetes Mellitus Tipo 2 , Pé Diabético , Infecção dos Ferimentos , Camundongos , Animais , Receptor 4 Toll-Like , Moléculas com Motivos Associados a Patógenos/uso terapêutico , Lipopolissacarídeos , Infecção dos Ferimentos/tratamento farmacológico , Pé Diabético/tratamento farmacológico , Antibacterianos/uso terapêutico , Imunidade , Citocinas
9.
Cancers (Basel) ; 15(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37190200

RESUMO

Mitogen-activated protein kinase (MAPK) cascades are crucial in extracellular signal transduction to cellular responses. The classical three-tiered MAPK cascades include signaling through MAP kinase kinase kinase (MAP3K) that activates a MAP kinase kinase (MAP2K), which in turn induces MAPK activation and downstream cellular responses. The upstream activators of MAP3K are often small guanosine-5'-triphosphate (GTP)-binding proteins, but in some pathways, MAP3K can be activated by another kinase, which is known as a MAP kinase kinase kinase kinase (MAP4K). MAP4K4 is one of the widely studied MAP4K members, known to play a significant role in inflammatory, cardiovascular, and malignant diseases. The MAP4K4 signal transduction plays an essential role in cell proliferation, transformation, invasiveness, adhesiveness, inflammation, stress responses, and cell migration. Overexpression of MAP4K4 is frequently reported in many cancers, including glioblastoma, colon, prostate, and pancreatic cancers. Besides its mainstay pro-survival role in various malignancies, MAP4K4 has been implicated in cancer-associated cachexia. In the present review, we discuss the functional role of MAP4K4 in malignant/non-malignant diseases and cancer-associated cachexia and its possible use in targeted therapy.

10.
Vaccines (Basel) ; 11(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36679904

RESUMO

Recent work has suggested involvement of the immune system in biological therapies specifically targeting tumor microenvironment. Substantial advancement in the treatment of malignant tumors utilizing immune cells, most importantly T cells that play a key role in cell-mediated immunity, have led to success in clinical trials. Therefore, this article focuses on the therapeutic approaches and developmental strategies to treat cancer. This review emphasizes the immunomodulatory response, the involvement of key tumor-infiltrating cells, the mechanistic aspects, and prognostic biomarkers. We also cover recent advancements in therapeutic strategies.

11.
J Invest Dermatol ; 142(3 Pt A): 692-704.e14, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34517005

RESUMO

Persistent inflammation is a major contributor to healing impairment in diabetic chronic wounds. Paradoxically, diabetic wound environment during the acute phase of healing is completely different because it exhibits a reduced macrophage response owing to inadequate expression of CCL2 proinflammatory cytokine. What causes a reduction in CCL2 expression in diabetic wounds early after injury remains unknown. In this study, we report that in contrast to prolonged exposure to high glucose, which makes monocytes proinflammatory, short-term exposure to high glucose causes a rapid monocyte reprogramming, manifested by increased expression and secretion of IL-10, which in an autocrine/paracrine fashion reduces glucose uptake and transforms monocytes into an anti-inflammatory phenotype by dampening signaling through toll-like receptors. We show that IL-10 expression is significantly increased in diabetic wounds during the acute phase of healing, causing significant reductions in toll-like receptor signaling and proinflammatory cytokine production, delaying macrophage and leukocyte responses, and underlying healing impairment in diabetic wounds. Importantly, blocking IL-10 signaling during the acute phase of healing improves toll-like receptor signaling, increases proinflammatory cytokine production, enhances macrophage and leukocyte responses, and stimulates healing in diabetic wounds. We posit that anti-IL-10 strategies have therapeutic potential if added topically after surgical debridement, which resets chronic wounds into acute fresh wounds.


Assuntos
Diabetes Mellitus , Interleucina-10 , Quimiocinas/metabolismo , Glucose/metabolismo , Humanos , Interleucina-10/metabolismo , Macrófagos/metabolismo
12.
Nat Commun ; 13(1): 1295, 2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35277504

RESUMO

Type 3 Secretion System (T3SS) is a highly conserved virulence structure that plays an essential role in the pathogenesis of many Gram-negative pathogenic bacteria, including Pseudomonas aeruginosa. Exotoxin T (ExoT) is the only T3SS effector protein that is expressed in all T3SS-expressing P. aeruginosa strains. Here we show that T3SS recognition leads to a rapid phosphorylation cascade involving Abl / PKCδ / NLRC4, which results in NLRC4 inflammasome activation, culminating in inflammatory responses that limit P. aeruginosa infection in wounds. We further show that ExoT functions as the main anti-inflammatory agent for P. aeruginosa in that it blocks the phosphorylation cascade through Abl / PKCδ / NLRC4 by targeting CrkII, which we further demonstrate to be important for Abl transactivation and NLRC4 inflammasome activation in response to T3SS and P. aeruginosa infection.


Assuntos
Proteínas Reguladoras de Apoptose , Proteínas de Ligação ao Cálcio , Infecções por Pseudomonas , Pseudomonas aeruginosa , ADP Ribose Transferases/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Exotoxinas/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Inflamassomos/metabolismo , Camundongos , Fosforilação , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/metabolismo , Sistemas de Secreção Tipo III/metabolismo
13.
Elife ; 112022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35112667

RESUMO

Infection is a major co-morbidity that contributes to impaired healing in diabetic wounds. Although impairments in diabetic neutrophils have been blamed for this co-morbidity, what causes these impairments and whether they can be overcome, remain largely unclear. Diabetic neutrophils, isolated from diabetic individuals, exhibit chemotaxis impairment but this peculiar functional impairment has been largely ignored because it appears to contradict the clinical findings which blame excessive neutrophil influx as a major impediment to healing in chronic diabetic ulcers. Here, we report that exposure to glucose in diabetic range results in impaired chemotaxis signaling through the formyl peptide receptor (FPR) in neutrophils, culminating in reduced chemotaxis and delayed neutrophil trafficking in the wound of Leprdb (db/db) type two diabetic mice, rendering diabetic wound vulnerable to infection. We further show that at least some auxiliary receptors remain functional under diabetic conditions and their engagement by the pro-inflammatory cytokine CCL3, overrides the requirement for FPR signaling and substantially improves infection control by jumpstarting the neutrophil trafficking toward infection, and stimulates healing in diabetic wound. We posit that CCL3 may have therapeutic potential for the treatment of diabetic foot ulcers if it is applied topically after the surgical debridement process which is intended to reset chronic ulcers into acute fresh wounds.


Assuntos
Quimiotaxia de Leucócito/imunologia , Diabetes Mellitus Experimental/imunologia , Neutrófilos/patologia , Receptores de Formil Peptídeo/genética , Transdução de Sinais/imunologia , Cicatrização/imunologia , Infecção dos Ferimentos/microbiologia , Animais , Quimiocina CCL3/imunologia , Complicações do Diabetes/microbiologia , Glucose/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/imunologia , Receptores de Formil Peptídeo/imunologia , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/etiologia
15.
Toxicol Lett ; 276: 69-84, 2017 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28495615

RESUMO

Our prior studies have reported that Benzanthrone (BA) manifests inflammatory responses in the spleen of Balb/c mice. The present investigation was carried out to study the impact of BA on macrophages, which are the primary scavenger cells in the body that act as a connecting link between innate and adaptive immunity. Parenteral administration of BA (daily for one week) to mice resulted in enhanced levels of nitric oxide (NO) and overexpression of inflammatory markers (COX-2, MMP-9 and PGE-2) in macrophages; however the level of MHC class-I and MHC class-II receptors were down regulated. Further, the potential membrane receptor targets (TLRs) of BA and its interaction with TLRs was investigated using computational methods. Professional phagocytes play pivotal roles in sensing bacteria through pathogen-associated molecular patterns (PAMPs) by various pathogen recognition receptors (PRRs), including Toll-like receptors (TLRs). Several studies have implicated these TLRs in the amplification of the inflammatory responses, however the fundamental role played by TLRs in mediating the inflammation associated with xenobiotics is still obscure and not understood. From the in silico analysis, it was evident that BA showed the highest binding affinity with TLR4 as compared to other TLRs. The western blotting studies confirmed that BA exposure indeed upregulated the expression of TLR 4, 5 and 9. Moreover, the downstream signaling cascade proteins of TLRs such as myeloid differentiation primary response protein-88 (MyD88), IL-1 receptor associated kinase (IRAK-1), and TNFR-associated factor (TRAF-6) were found to be enhanced in the BA treated groups. It was also observed that BA treatment increased the expression of ICAM-1, p-Lyn, p-Syk, p-PI3-K, IP3, PLC-γ, cAMP and Ca+2 influx, which are known to play a critical role in TLR mediated inflammation. Earlier we found that toxic effects of BA in spleen were mediated by oxidative stress which was partially neutralized by NAC exposure. Hereby, we report that NAC treatment in conjunction with BA attenuated the expression of BA induced TLR4, as well as the inflammatory markers such as COX2 and p-NFkB in macrophages. These findings demonstrated the critical role of TLRs in the regulation of the BA-induced inflammation.


Assuntos
Benzo(a)Antracenos/toxicidade , Poluentes Ambientais/toxicidade , Inflamação/induzido quimicamente , Macrófagos Peritoneais/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Benzo(a)Antracenos/metabolismo , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Relação Dose-Resposta a Droga , Poluentes Ambientais/metabolismo , Feminino , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Simulação de Acoplamento Molecular , Estresse Oxidativo/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Ligação Proteica , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Regulação para Cima
16.
J Natl Cancer Inst ; 109(6)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28040797

RESUMO

Background: A nontoxic chemopreventive intervention efficacious against different subtypes of breast cancer is still a clinically unmet need. The present study was undertaken to determine the efficacy of an Ayurvedic medicine phytochemical (Withaferin A, [WA]) for chemoprevention of breast cancer and to elucidate its mode of action. Methods: Chemopreventive efficacy of WA (4 and 8 mg/kg body weight) was determined using a rat model of breast cancer induced by N-methyl-N-nitrosourea (MNU; n = 14 for control group, n = 15 for 4 mg/kg group, and n = 18 for 8 mg/kg group). The mechanisms underlying breast cancer chemoprevention by WA were elucidated by immunoblotting, biochemical assays, immunohistochemistry, and cytokine profiling using plasma and tumors from the MNU-rat (n = 8-12 for control group, n = 7-11 for 4 mg/kg group, and n = 8-12 for 8 mg/kg group) and/or mouse mammary tumor virus-neu (MMTV-neu) models (n = 4-11 for control group and n = 4-21 for 4 mg/kg group). Inhibitory effect of WA on exit from mitosis and leptin-induced oncogenic signaling was determined using MCF-7 and/or MDA-MB-231 cells. All statistical tests were two-sided. Results: Incidence, multiplicity, and burden of breast cancer in rats were decreased by WA administration. For example, the tumor weight in the 8 mg/kg group was lower by about 68% compared with controls (8 mg/kg vs control, mean = 2.76 vs 8.59, difference = -5.83, 95% confidence interval of difference = -9.89 to -1.76, P = .004). Mitotic arrest and apoptosis induction were some common determinants of breast cancer chemoprevention by WA in the MNU-rat and MMTV-neu models. Cytokine profiling showed suppression of plasma leptin levels by WA in rats. WA inhibited leptin-induced oncogenic signaling in cultured breast cancer cells. Conclusions: WA is a promising chemopreventative phytochemical with the ability to inhibit at least two different subtypes of breast cancer.


Assuntos
Neoplasias da Mama/prevenção & controle , Neoplasias Mamárias Experimentais/prevenção & controle , Vírus do Tumor Mamário do Camundongo , Infecções por Retroviridae/complicações , Infecções Tumorais por Vírus/complicações , Vitanolídeos/uso terapêutico , 8-Hidroxi-2'-Desoxiguanosina , Acetilcoenzima A/sangue , Família Aldeído Desidrogenase 1 , Animais , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/análise , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Citocinas/sangue , Desoxiguanosina/análogos & derivados , Desoxiguanosina/análise , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Fatores de Transcrição Forkhead/análise , Humanos , Antígeno Ki-67/análise , Ácido Láctico/sangue , Leptina/sangue , Células MCF-7 , Malatos/sangue , Neoplasias Mamárias Experimentais/química , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/virologia , Metilnitrosoureia , Camundongos , Mitose/efeitos dos fármacos , Índice Mitótico , Ratos , Receptores de Estrogênio/análise , Retinal Desidrogenase/análise , Transdução de Sinais/efeitos dos fármacos , Carga Tumoral , Vitanolídeos/análise , Vitanolídeos/farmacologia
17.
J Immunotoxicol ; 13(6): 827-841, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27967302

RESUMO

Epicutaneous (EC) sensitization to food allergens may occur when the skin has been lightly damaged. The study here tested whether cutaneous exposure to pigeon pea protein(s) may cause allergic sensitization. BALB/c mice were either orally gavaged or epicutaneously sensitized by repeated application of pigeon pea crude protein extract (CPE) on undamaged areas of skin without any adjuvant; afterwards, both groups were orally challenged with the pigeon pea CPE. Anaphylactic symptoms along with measures of body temperature, MCPT-1, TSLP, pigeon pea-specific IgE and IgG1, myeloperoxidase (MPO) activity, TH2 cytokines, TH2 transcription factors (TFs) and filaggrin expression were determined. Mast cell staining, eosinophil levels and histopathological analysis of the skin and intestines were also performed. In the epicutaneously-sensitized mice, elevated levels of specific IgE and IgG1, as well as of MCPT-1, TSLP, TH2 cytokines and TFs, higher anaphylactic scores and histological changes in the skin and intestine were indicative of sensitization ability via both routes in the pigeon pea CPE-treated hosts. Elevated levels of mast cells were observed in both the skin and intestine; increased levels of eosinophils and MPO activity were noted only in the skin. Decreased levels of filaggrin in skin may have played a key role in the skin barrier dysfunction, increasing the chances of sensitization. Therefore, the experimental data support the hypothesis that in addition to oral exposure, skin exposure to food allergens can promote TH2-dependent sensitization, IgE-mediated anaphylaxis and intestinal changes after oral challenge. Based on this, an avoidance of cutaneous exposures to allergens might prevent development of food anaphylaxis.


Assuntos
Anafilaxia/imunologia , Eosinófilos/imunologia , Hipersensibilidade Alimentar/imunologia , Pele/imunologia , Células Th2/imunologia , Alérgenos/imunologia , Animais , Antígenos de Plantas/imunologia , Cajanus/imunologia , Células Cultivadas , Quimases/metabolismo , Citocinas/metabolismo , Proteínas Filagrinas , Humanos , Imunização , Imunoglobulina E/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/imunologia
18.
Mol Immunol ; 63(2): 184-92, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25193324

RESUMO

The use of nanoscale materials is growing exponentially as concerns rise about the human hazards to it. It is assumed that living beings are coevolved with nanoparticles ever since the origin of life on earth and therefore, they must have developed the defense and toxicity mitigating mechanisms for nanoparticles. Although having peculiar properties these new materials also present new health risks upon interacting with biological systems. Zinc oxide is the most widely used nanoparticles among various nanomaterials. Recently, these nanoparticles have been shown to specifically kill cancerous cells; therefore, it is believed that these nanoparticles may be used as an alternative anti-tumor agent. However, it is also known that these nanoparticles pose several deleterious effects to living beings. It is therefore critical to understand the nature and origin of the toxicity imposed by these nanomaterials. Keeping these points in mind the present review provides updated information on various aspects of toxicities induced by these engineered nanoparticles.


Assuntos
Linfócitos/efeitos dos fármacos , Nanopartículas/toxicidade , Óxido de Zinco/toxicidade , Animais , Endocitose/efeitos dos fármacos , Humanos , Linfócitos/citologia , Mutagênicos/toxicidade , Nanopartículas/química , Tamanho da Partícula , Óxido de Zinco/química
20.
Immunobiology ; 220(3): 369-81, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25454808

RESUMO

Benzanthrone (BA) is an important dye intermediate which is used in the manufacturing of several polycyclic vat and disperse dyes in textile industries. Several studies have indicated that the general population is also exposed to BA owing to its release from furnace effluents and automobile exhausts in the environment. In several clinical studies, it has been shown that workers exposed to BA developed itching, burning sensation, erythema and hyperpigmentation of the skin, which could be an outcome of the dysregulated immune response. In this study, we have used female Balb/c mice as a model to study the immuno-inflammatory changes after systemic administration of BA (7.5mg/kgb.w. and 15mg/kgb.w.) for one week. BA exposed animals exhibited the signs of intense systemic inflammation as evident by enhanced DTH response, MPO activity, hyperplastic and dysplastic histopathological organization of spleen and lung tissue. Splenic evaluation revealed enhanced oxidative stress, upregulation of prominent inflammatory markers like iNOS and COX-2 and DNA damage. In coherence with the observed immuno-inflammatory alterations, the levels of several inflammatory and regulatory cytokines (IL-17, TNF-α, IFN-γ, IL-1, IL-10, IL-4) were significantly enhanced in serum as well as the spleen. In addition, BA administration significantly induced the activation of ERK1/2, p38, JNK MAPKs and their downstream transcription factors AP-1 (c-fos, c-jun), NF-κB and Nrf2 which comprise important mechanistic pathways involved in inflammatory manifestations. These results suggest the immunotoxic nature of the BA and have implications for the risk assessment and management of occupational workers, and even common masses considering its presence as an environmental contaminant.


Assuntos
Benzo(a)Antracenos/farmacologia , Mediadores da Inflamação/metabolismo , Inflamação/induzido quimicamente , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Ciclo-Oxigenase 2/biossíntese , Citocinas/sangue , Citocinas/metabolismo , Dano ao DNA/efeitos dos fármacos , Feminino , Inflamação/imunologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Exposição Ocupacional/efeitos adversos , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Baço/patologia , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos
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