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1.
FASEB J ; 35(9): e21777, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34403519

RESUMO

Mycobacterium bovis is the causative agent of bovine tuberculosis and also responsible for serious threat to public health. Koumiss is a fermented mare's milk product, used as traditional drink. Here, we explored the effect of koumiss on gut microbiota and the host immune response against M bovis infection. Therefore, mice were treated with koumiss and fresh mare milk for 14 days before M bovis infection and continue for 5 weeks after infection. The results showed a clear change in the intestinal flora of mice treated with koumiss, and the lungs of mice treated with koumiss showed severe edema, inflammatory infiltration, and pulmonary nodules in M bovis-infected mice. Notably, we found that the content of short-chain fatty acids was significantly lower in the koumiss-treated group compared with the control group. However, the expression of endoplasmic reticulum stress and apoptosis-related proteins in the lungs of koumiss-treated mice were significantly decreased. Collectively, these findings suggest that koumiss treatment disturb the intestinal flora of, which is associated with disease severity and the possible mechanism that induces lungs pathology. Our current findings can be exploited further to establish the "gut-lung" axis which might be a novel strategy for the control of tuberculosis.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Kumis/efeitos adversos , Mycobacterium bovis/efeitos dos fármacos , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/patologia , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Ácidos Graxos/análise , Fezes/química , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/imunologia , Cavalos , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium bovis/imunologia , Tuberculose Pulmonar/dietoterapia , Tuberculose Pulmonar/metabolismo
2.
Vet Microbiol ; 258: 109126, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34020176

RESUMO

Mycobacterium bovis (M. bovis) infection triggers cytokine production via pattern recognition receptors. These cytokines include type I interferons (IFNs) and interleukin-1ß (IL-1ß). Excessive type I IFN levels impair host resistance to M. bovis infection. Therefore, strict control of type I IFN production is helpful to reduce pathological damage and bacterial burden. Here, we found that a deficiency in caspase-1, which is the critical component of the inflammasome responsible for IL-1ß production, resulted in increased IFN-ß production upon M. bovis infection. Subsequent experiments demonstrated that caspase-1 activation reduced cyclic GMP-AMP synthase (cGAS) expression, thereby inhibiting downstream TANK-binding kinase 1 (TBK1)- interferon regulatory factor 3 (IRF3) signaling and ultimately reducing IFN production. A deficiency in caspase-1 activation enhanced the bacterial burden during M. bovis infection in vitro and in vivo and aggravated pathological lesion formation. Thus, caspase-1 activation reduced IFN-ß production upon M. bovis infection by dampening cGAS-TBK1-IRF3 signaling, suggesting that the inflammasome protects hosts by negatively regulating harmful cytokines.


Assuntos
Caspase 1/metabolismo , Animais , Inibidores de Caspase/farmacologia , Sobrevivência Celular , Dipeptídeos/farmacologia , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Inflamassomos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Interferon beta , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium bovis , Nucleotidiltransferases , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Distribuição Aleatória , para-Aminobenzoatos/farmacologia
3.
Animals (Basel) ; 11(3)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33668845

RESUMO

BACKGROUND: The use of wheat and flaxseed to produce omega-3 (ω-3) enriched poultry meat and eggs is very popular in the world. However, wheat and flaxseed contain some anti-nutritional factors (ANFs), and enzymes are usually used to alleviate the deleterious influence of ANFs. METHOD: A 2 × 3 two factors design was used in the experiment. A total of 540 twenty-week-old Nongda-3 laying hens were randomly allocated to six dietary treatments, two diets (corn/flaxseed and wheat/flaxseed), and three enzymes (enzyme-a contains neutral protease 10,000, xylanase 35,000, ß-mannanase 1500, ß-glucanase 2000, cellulose 500, amylase 100, and pectinase 10,000 (U g-1); enzyme-b contains alkaline protease 40,000 and neutral protease 10,000 (U g-1); enzyme-c contains alkaline protease 40,000, neutral protease 10,000, and cellulase 4000 (U g-1). RESULTS: There was an interaction between dietary treatment and supplemental enzymes for liver weight and liver inflammatory cytokines of broilers. A significant increase was observed in the fat weight of birds fed a corn diet as compared with a wheat diet. A corn diet and wheat diet with the addition of enzyme-a (p < 0.001) showed the highest level of liver fat followed by enzyme-c (p < 0.01) and enzyme-b. Moreover, a high level of secretory IL-1ß, IL-6, and IL-10 and comparatively higher inflammatory changes in the liver tissue were found in birds fed a corn diet as compared with a wheat diet, and enzyme-b showed more beneficial effects as compared with enzyme-a and -c. The gut microbial composition of hens fed a corn diet was significantly different than that of birds fed a wheat diet. Bacteroides were significantly (p < 0.05) abundant in the corn-fed birds as compared with wheat-fed birds. However, Firmicutes were less abundant in the wheat-fed birds than the corn-fed birds (16.99 vs. 31.80%, respectively). The microbial community at the genus level differed significantly in the dietary groups and we observed that Bacteroides are the predominant cecal microbiota. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of co-factors, carbohydrates, vitamins, protein, and energy were expressed at slightly higher levels in the microbiota of the wheat-fed birds, whereas, metabolic pathways for nucleotides, lipids, and glycine were expressed at higher levels in the wheat-fed birds. Furthermore, expression of the growth and cellular processes pathway and endocrine system pathway levels were predicted to be higher for the wheat-fed group as compared with the corn-fed group. CONCLUSIONS: In conclusion, our findings suggest that inflammatory changes in laying birds were mediated by a corn diet with flaxseed and enzymes instead of a wheat diet. Additionally, in the wheat-fed group, enzyme-b and -c showed more encouraging results as compared to enzyme-a.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32582649

RESUMO

CATH-2TP5 is a linear cationic hybrid peptide, consequent from naturally occurring antimicrobial peptide (AMPs) Cathelicidin-2 (CATH-2) and Immunomodulatory peptide Thymopentin (TP5) having dynamic and potent anti-inflammatory activities without hemolytic effect. The biocompatible mechanism of CATH-2TP5 is favored to explore new methodologies in the direction of biomedical applications. In this retrospectively study, an antiendotoxin and anti-inflammatory hybrid peptide CATH-2TP5 was emulated into pPICZα-A and successfully expressed in Pichia pastoris (P. pastoris). The recombinant CATH-2TP5 was purified through the Ni-affinity column and reversed-phase HPLC. The purified CATH-2TP5 peptide exhibited robust anti-endotoxin activity and significantly (p < 0.05) neutralized the effect of lipopolysaccharide (LPS). Furthermore, the down-regulated effect of CATH-2TP was more pronounced (p < 0.05) on LPS-induced cytotoxic effects, nitric oxide secretion and pro-inflammatory cytokines (TNF-α, IL-6, and IL-1ß) in murine RAW264.7 macrophages. As associated to control and parental peptide the number of apoptotic cells was also contracted with the treatment of CATH-2TP5. Thus, we concluded that CATH-2TP5 peptide may be used in various biomedical applications as a therapeutic drug.

5.
J Infect Dis ; 221(3): 438-448, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31495880

RESUMO

BACKGROUND: Mycobacterium bovis persistently survives in macrophages by developing multiple strategies to evade host immune responses, and the early induction of interferon-ß (IFN-ß) is one of these critical strategies. The mitochondrial transcription factor A (TFAM) plays a vital role in mitochondrial DNA (mtDNA) metabolism and has been suggested to influence IFN-ß production in response to viral infection. However, its role in the production of IFN-ß by M. bovis has not been elucidated. METHODS: In the current study, we investigated the role of TFAM in the production of IFN-ß in M. bovis-infected macrophages. RESULTS: We found that knockdown of TFAM expression significantly reduced M. bovis-induced IFN-ß production, mtDNA copy numbers and cytosolic mtDNA were increased in murine macrophages with M. bovis infection, cytosolic mtDNA contributed to IFN-ß production, and TFAM was required for the increase in mtDNA copy numbers induced by M. bovis. We also observed that TFAM affected the intracellular survival of M. bovis. CONCLUSIONS: Our results suggest that TFAM plays an essential role in M. bovis-induced IFN-ß production by regulating mtDNA copy numbers. This might be a new strategy adopted by M. bovis for its intracellular survival.


Assuntos
Replicação do DNA , DNA Mitocondrial/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Grupo de Alta Mobilidade/metabolismo , Interferon beta/biossíntese , Macrófagos/imunologia , Mycobacterium bovis/imunologia , Tuberculose/imunologia , Tuberculose/veterinária , Animais , Linhagem Celular Tumoral , Citosol/metabolismo , DNA Mitocondrial/metabolismo , Proteínas de Ligação a DNA/genética , Técnicas de Silenciamento de Genes , Proteínas de Grupo de Alta Mobilidade/genética , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mycobacterium bovis/metabolismo , Transdução de Sinais/genética , Tuberculose/microbiologia
6.
BMC Infect Dis ; 19(1): 1031, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31801478

RESUMO

BACKGROUND: Mycobacterium bovis (M. bovis) is the principal causative agent of bovine tuberculosis; however, it may also cause serious infection in human being. Type I IFN is a key factor in reducing viral multiplication and modulating host immune response against viral infection. However, the regulatory pathways of Type I IFN signaling during M. bovis infection are not yet fully explored. Here, we investigate the role of Type I IFN signaling in the pathogenesis of M. bovis infection in mice. METHODS: C57BL/6 mice were treated with IFNAR1-blocking antibody or Isotype control 24 h before M. bovis infection. After 21 and 84 days of infection, mice were sacrificed and the role of Type I IFN signaling in the pathogenesis of M. bovis was investigated. ELISA and qRT-PCR were performed to detect the expression of Type I IFNs and related genes. Lung lesions induced by M. bovis were assessed by histopathological examination. Viable bacterial count was determined by CFU assay. RESULTS: We observed an abundant expression of Type I IFNs in the serum and lung tissues of M. bovis infected mice. In vivo blockade of Type I IFN signaling reduced the recruitment of neutrophils to the lung tissue, mediated the activation of macrophages leading to an increased pro-inflammatory profile and regulated the inflammatory cytokine production. However, no impact was observed on T cell activation and recruitment in the early acute phase of infection. Additionally, blocking of type I IFN signaling reduced bacterial burden in the infected mice as compared to untreated infected mice. CONCLUSIONS: Altogether, our results reveal that Type I IFN mediates a balance between M. bovis-mediated inflammatory reaction and host defense mechanism. Thus, modulating Type I IFN signaling could be exploited as a therapeutic strategy against a large repertoire of inflammatory disorders including tuberculosis.


Assuntos
Interferon Tipo I/metabolismo , Mycobacterium bovis/patogenicidade , Tuberculose/tratamento farmacológico , Tuberculose/metabolismo , Animais , Anticorpos/farmacologia , Citocinas/metabolismo , Feminino , Humanos , Interferon Tipo I/antagonistas & inibidores , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Mycobacterium bovis/imunologia , Receptor de Interferon alfa e beta/antagonistas & inibidores , Receptor de Interferon alfa e beta/imunologia , Transdução de Sinais/efeitos dos fármacos
7.
Int J Mol Sci ; 20(23)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795474

RESUMO

Mycobacterium bovis (M. bovis) is the causative agent of bovine tuberculosis in cattle population across the world. Human beings are at equal risk of developing tuberculosis beside a wide range of M. bovis infections in animal species. Autophagic sequestration and degradation of intracellular pathogens is a major innate immune defense mechanism adopted by host cells for the control of intracellular infections. It has been reported previously that the catalytic subunit of protein phosphatase 2A (PP2Ac) is crucial for regulating AMP-activated protein kinase (AMPK)-mediated autophagic signaling pathways, yet its role in tuberculosis is still unclear. Here, we demonstrated that M. bovis infection increased PP2Ac expression in murine macrophages, while nilotinib a tyrosine kinase inhibitor (TKI) significantly suppressed PP2Ac expression. In addition, we observed that TKI-induced AMPK activation was dependent on PP2Ac regulation, indicating the contributory role of PP2Ac towards autophagy induction. Furthermore, we found that the activation of AMPK signaling is vital for the regulating autophagy during M. bovis infection. Finally, the transient inhibition of PP2Ac expression enhanced the inhibitory effect of TKI-nilotinib on intracellular survival and multiplication of M. bovis in macrophages by regulating the host's immune responses. Based on these observations, we suggest that PP2Ac should be exploited as a promising molecular target to intervene in host-pathogen interactions for the development of new therapeutic strategies towards the control of M. bovis infections in humans and animals.


Assuntos
Proteínas Quinases Ativadas por AMP/imunologia , Macrófagos/imunologia , Mycobacterium bovis/imunologia , Proteína Fosfatase 2/imunologia , Tuberculose/veterinária , Animais , Autofagia , Bovinos , Interações Hospedeiro-Patógeno , Humanos , Macrófagos/microbiologia , Camundongos , Mycobacterium bovis/fisiologia , Fagocitose , Células RAW 264.7 , Tuberculose/imunologia , Tuberculose/microbiologia , Tuberculose Bovina/imunologia , Tuberculose Bovina/microbiologia
8.
Cell Prolif ; 52(4): e12649, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31199047

RESUMO

Mycobacterium tuberculosis (Mtb) leads to approximately 1.5 million human deaths every year. In pulmonary tuberculosis (TB), Mtb must drive host tissue destruction to cause pulmonary cavitation and dissemination in the tissues. Matrix metalloproteinases (MMPs) are endopeptidases capable of degrading all components of pulmonary extracellular matrix (ECM). It is well established that Mtb infection leads to upregulation of MMPs and also causes disturbance in the balance between MMPs and tissue inhibitors of metalloproteinases (TIMPs), thus altering the extracellular matrix deposition. In TB, secretion of MMPs is mainly regulated by NF-κB, p38 and MAPK signalling pathways. In addition, recent studies have demonstrated the immunomodulatory roles of MMPs in Mtb pathogenesis. Researchers have proposed a new regimen of improved TB treatment by inhibition of MMP activity to hinder matrix destruction and to minimize the TB-associated morbidity and mortality. The proposed regimen involves adjunctive use of MMP inhibitors such as doxycycline, marimastat and other related drugs along with front-line anti-TB drugs to reduce granuloma formation and bacterial load. These findings implicate the possible addition of economical and well-tolerated MMP inhibitors to current multidrug regimens as an attractive mean to increase the drug potency. Here, we will summarize the recent advancements regarding expression of MMPs in TB, their immunomodulatory role, as well as their potential as therapeutic targets to control the deadly disease.


Assuntos
Metaloproteinases da Matriz/metabolismo , Mycobacterium tuberculosis/patogenicidade , Tuberculose Pulmonar/metabolismo , Tuberculose Pulmonar/patologia , Animais , Matriz Extracelular/metabolismo , Humanos , Pulmão/metabolismo , Pulmão/patologia , Transdução de Sinais/fisiologia
9.
Cells ; 8(5)2019 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060300

RESUMO

Mycobacterium bovis (M. bovis) is a member of the Mycobacterium tuberculosis (Mtb) complex causing bovine tuberculosis (TB) and imposing a high zoonotic threat to human health. Kallikreins (KLKs) belong to a subgroup of secreted serine proteases. As their role is established in various physiological and pathological processes, it is likely that KLKs expression may mediate a host immune response against the M. bovis infection. In the current study, we report in vivo and in vitro upregulation of KLK12 in the M. bovis infection. To define the role of KLK12 in immune response regulation of murine macrophages, we produced KLK12 knockdown bone marrow derived macrophages (BMDMs) by using siRNA transfection. Interestingly, the knockdown of KLK12 resulted in a significant downregulation of autophagy and apoptosis in M. bovis infected BMDMs. Furthermore, we demonstrated that this KLK12 mediated regulation of autophagy and apoptosis involves mTOR/AMPK/TSC2 and BAX/Bcl-2/Cytochrome c/Caspase 3 pathways, respectively. Similarly, inflammatory cytokines IL-1ß, IL-6, IL-12 and TNF-α were significantly downregulated in KLK12 knockdown macrophages but the difference in IL-10 and IFN-ß expression was non-significant. Taken together, these findings suggest that upregulation of KLK12 in M. bovis infected murine macrophages plays a substantial role in the protective immune response regulation by modulating autophagy, apoptosis and pro-inflammatory pathways. To our knowledge, this is the first report on expression and the role of KLK12 in the M. bovis infection and the data may contribute to a new paradigm for diagnosis and treatment of bovine TB.


Assuntos
Apoptose , Autofagia , Imunidade Inata , Calicreínas/metabolismo , Macrófagos/patologia , Mycobacterium bovis/fisiologia , Tuberculose Bovina/imunologia , Tuberculose Bovina/microbiologia , Animais , Bovinos , Citocinas/metabolismo , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Viabilidade Microbiana , Células RAW 264.7 , Transdução de Sinais , Tuberculose Bovina/patologia
10.
Cells ; 8(5)2019 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-31130711

RESUMO

Nilotinib, a tyrosine kinase inhibitor, has been studied extensively in various tumor models; however, no information exists about the pharmacological action of nilotinib in bacterial infections. Mycobacterium bovis (M. bovis) and Mycobacterium avium subspecies paratuberculosis (MAP) are the etiological agents of bovine tuberculosis and Johne's disease, respectively. Although M. bovis and MAP cause distinct tissue tropism, both of them infect, reside, and replicate in mononuclear phagocytic cells of the infected host. Autophagy is an innate immune defense mechanism for the control of intracellular bacteria, regulated by diverse signaling pathways. Here we demonstrated that nilotinib significantly inhibited the intracellular survival and growth of M. bovis and MAP in macrophages by modulating host immune responses. We showed that nilotinib induced autophagic degradation of intracellular mycobacterium occurred via the inhibition of PI3k/Akt/mTOR axis mediated by abelson (c-ABL) tyrosine kinase. In addition, we observed that nilotinib promoted ubiquitin accumulation around M. bovis through activation of E3 ubiquitin ligase parkin. From in-vivo experiments, we found that nilotinib effectively controlled M. bovis growth and survival through enhanced parkin activity in infected mice. Altogether, our data showed that nilotinib regulates protective innate immune responses against intracellular mycobacterium, both in-vitro and in-vivo, and can be exploited as a novel therapeutic remedy for the control of M. bovis and MAP infections.


Assuntos
Autofagia/efeitos dos fármacos , Mycobacterium avium subsp. paratuberculosis/efeitos dos fármacos , Mycobacterium bovis/efeitos dos fármacos , Paratuberculose/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Tuberculose Bovina/tratamento farmacológico , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citoplasma/metabolismo , Citoplasma/microbiologia , Feminino , Imunidade Inata/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteína Oncogênica v-akt/metabolismo , Paratuberculose/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas c-abl/metabolismo , Pirimidinas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Tuberculose Bovina/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
11.
Front Immunol ; 10: 268, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30846986

RESUMO

Mycobacterium bovis, the causative agent of tuberculosis in cattle and humans, infects host macrophages and induces endoplasmic reticulum stress (ERS), mitochondrial damage, and interleukin (IL)-1ß production. The relationship between these phenotypes is yet to be elucidated. In this study, we investigated the role of ERS in mitochondrial damage and IL-1ß production in macrophages during infection with a virulent M. bovis strain. We found that ERS activates the inflammasome via NOD-like receptor family, pyrin domain-containing 3 (NLRP3)-caspase-8 and that IFN-inducible protein absent in melanoma 2 (AIM2) triggered mitochondrial damage. ERS increased reactive oxygen species (ROS), which promoted translocation of the inflammasome to the mitochondria. NLRP3, but not AIM2, was involved in the ERS-induced cleavage of caspase-8 and Bid, leading to mitochondrial damage, which was required for the production of mature IL-1ß. Our data suggest that ERS induces macrophages to produce mature IL-1ß during infection with virulent M. bovis through a positive feedback loop between mitochondrial damage and inflammasome activation. To the best of our knowledge, this is the first evidence of the involvement of ERS and mitochondrial damage in inflammasome activation during M. bovis infection.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Mitocôndrias/metabolismo , Infecções por Mycobacterium/metabolismo , Mycobacterium bovis/patogenicidade , Animais , Caspases/metabolismo , Células Cultivadas , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo
12.
Int J Mol Sci ; 20(5)2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30845718

RESUMO

Transcription factors play a significant role during the symptomatic onset and progression of prion diseases. We previously showed the immunomodulatory and nuclear factor of activated T cells' (NFAT) suppressive effects of an immunosuppressant, FK506, in the symptomatic stage and an antibiotic, minocycline, in the pre-symptomatic stage of prion infection in hamsters. Here we used for the first time, a combinatory FK506+minocycline treatment to test its transcriptional modulating effects in the symptomatic stage of prion infection. Our results indicate that prolonged treatment with FK506+minocycline was effective in alleviating astrogliosis and neuronal death triggered by misfolded prions. Specifically, the combinatory therapy with FK506+minocycline lowered the expression of the astrocytes activation marker GFAP and of the microglial activation marker IBA-1, subsequently reducing the level of pro-inflammatory cytokines interleukin 1 beta (IL-1ß) and tumor necrosis factor alpha (TNF-α), and increasing the levels of anti-inflammatory cytokines IL-10 and IL-27. We further found that FK506+minocycline treatment inhibited mitogen-activated protein kinase (MAPK) p38 phosphorylation, NF-kB nuclear translocation, caspase expression, and enhanced phosphorylated cAMP response element-binding protein (pCREB) and phosphorylated Bcl2-associated death promoter (pBAD) levels to reduce cognitive impairment and apoptosis. Interestingly, FK506+minocycline reduced mitochondrial fragmentation and promoted nuclear factor⁻erythroid2-related factor-2 (NRF2)-heme oxygenase 1 (HO-1) pathway to enhance survival. Taken together, our results show that a therapeutic cocktail of FK506+minocycline is an attractive candidate for prolonged use in prion diseases and we encourage its further clinical development as a possible treatment for this disease.


Assuntos
Minociclina/administração & dosagem , Doenças Priônicas/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Tacrolimo/administração & dosagem , Animais , Caspases/metabolismo , Morte Celular/efeitos dos fármacos , Cricetinae , Modelos Animais de Doenças , Regulação para Baixo , Quimioterapia Combinada , Proteína Glial Fibrilar Ácida/metabolismo , Minociclina/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Doenças Priônicas/imunologia , Doenças Priônicas/metabolismo , Tacrolimo/farmacologia
13.
Int J Mol Sci ; 20(1)2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30577452

RESUMO

It is widely accepted that different strains of Mycobacterium tuberculosis have variable degrees of pathogenicity and induce different immune responses in infected hosts. Similarly, different strains of Mycobacterium bovis have been identified but there is a lack of information regarding the degree of pathogenicity of these strains and their ability to provoke host immune responses. Therefore, in the current study, we used a mouse model to evaluate various factors involved in the severity of disease progression and the induction of immune responses by two strains of M. bovis isolated from cattle. Mice were infected with both strains of M. bovis at different colony-forming unit (CFU) via inhalation. Gross and histological findings revealed more severe lesions in the lung and spleen of mice infected with M. bovis N strain than those infected with M. bovis C68004 strain. In addition, high levels of interferon-γ (IFN-γ), interleukin-17 (IL-17), and IL-22 production were observed in the serum samples of mice infected with M. bovis N strain. Comparative genomic analysis showed the existence of 750 single nucleotide polymorphisms and 145 small insertions/deletions between the two strains. After matching with the Virulence Factors Database, mutations were found in 29 genes, which relate to 17 virulence factors. Moreover, we found an increased number of virulent factors in M. bovis N strain as compared to M. bovis C68004 strain. Taken together, our data reveal that variation in the level of pathogenicity is due to the mutation in the virulence factors of M. bovis N strain. Therefore, a better understanding of the mechanisms of mutation in the virulence factors will ultimately contribute to the development of new strategies for the control of M. bovis infection.


Assuntos
Interações Hospedeiro-Patógeno/imunologia , Mycobacterium bovis , Tuberculose Bovina/genética , Tuberculose Bovina/microbiologia , Animais , Biópsia , Bovinos , Citocinas/sangue , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Patógeno/genética , Pulmão/patologia , Camundongos , Tipagem de Sequências Multilocus , Mutação , Mycobacterium bovis/classificação , Mycobacterium bovis/genética , Mycobacterium bovis/imunologia , Mycobacterium bovis/patogenicidade , Polimorfismo de Nucleotídeo Único , Baço/patologia , Tuberculose Bovina/imunologia , Virulência/genética , Fatores de Virulência
14.
Front Mol Neurosci ; 11: 310, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30337853

RESUMO

Prion diseases are a group of fatal and debilitating neurodegenerative diseases affecting humans and animal species. The conversion of a non-pathogenic normal cellular protein (PrPc) into an abnormal infectious, protease-resistant, pathogenic form prion protein scrapie (PrPSc), is considered the etiology of these diseases. PrPSc accumulates in the affected individual's brain in the form of extracellular plaques. The molecular pathways leading to neuronal cell death in prion diseases are still unclear. The free radical damage, oxidative stress and mitochondrial dysfunction play a key role in the pathogenesis of the various neurodegenerative disorders including prion diseases. The brain is very sensitive to changes in the redox status. It has been demonstrated that PrPc behaves as an antioxidant, while the neurotoxic prion peptide PrPSc increases hydrogen peroxide toxicity in the neuronal cultures leading to mitochondrial dysfunction and cell death. The nuclear factor erythroid 2-related factor 2 (NRF2) is an oxidative responsive pathway and a guardian of lifespan, which protect the cells from free radical stress-mediated cell death. The reduced glutathione, a major small molecule antioxidant present in all mammalian cells, and produced by several downstream target genes of NRF2, counterbalances the mitochondrial reactive oxygen species (ROS) production. In recent years, it has emerged that the ubiquitin-binding protein, p62-mediated induction of autophagy, is crucial for NRF2 activation and elimination of mitochondrial dysfunction and oxidative stress. The current review article, focuses on the role of NRF2 pathway in prion diseases to mitigate the disease progression.

15.
Front Aging Neurosci ; 10: 139, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867448

RESUMO

Prion diseases are fatal neurological disorders affecting various mammalian species including humans. Lack of proper diagnostic tools and non-availability of therapeutic remedies are hindering the control strategies for prion diseases. MicroRNAs (miRNAs) are abundant endogenous short non-coding essential RNA molecules that negatively regulate the target genes after transcription. Several biological processes depend on miRNAs, and altered profiles of these miRNAs are potential biomarkers for various neurodegenerative diseases, including prion diseases. Autophagic flux degrades the misfolded prion proteins to reduce chronic endoplasmic reticulum stress and enhance cell survival. Recent evidence suggests that specific miRNAs target and regulate the autophagic mechanism, which is critical for alleviating cellular stress. miRNAs-mediated regulation of these specific proteins involved in the autophagy represents a new target with highly significant therapeutic prospects. Here, we will briefly describe the biology of miRNAs, the use of miRNAs as potential biomarkers with their credibility, the regulatory mechanism of miRNAs in major neurodegenerative diseases such as Alzheimer's, Parkinson's, and prion diseases, degradation pathways for aggregated prion proteins, the role of autophagy in prion diseases. Finally, we will discuss the miRNAs-modulated autophagic flux in neurodegenerative diseases and employ them as potential therapeutic intervention strategy in prion diseases.

16.
Front Microbiol ; 9: 602, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29651283

RESUMO

Tuberculosis (TB) is one of the most fatal infectious diseases and a leading cause of mortality, with 95% of these deaths occurring in developing countries. The causative agent, Mycobacterium tuberculosis (Mtb), has a well-established ability to circumvent the host's immune system for its intracellular survival. microRNAs (miRNAs) are small, non-coding RNAs having an important function at the post-transcriptional level and are involved in shaping immunity by regulating the repertoire of genes expressed in immune cells. It has been established in recent studies that the innate immune response against TB is significantly regulated by miRNAs. Moreover, differential expression of miRNA in Mtb infection can reflect the disease progression and may help distinguish between active and latent TB infection (LTBI). These findings encouraged the application of miRNAs as potential biomarkers. Similarly, active participation of miRNAs in modulation of autophagy and apoptosis responses against Mtb opens an exciting avenue for the exploitation of miRNAs as host directed therapy (HDT) against TB. Nanoparticles mediated delivery of miRNAs to treat various diseases has been reported and this technology has a great potential to be used in TB. In reality, this exploitation of miRNAs as biomarkers and in HDT is still in its infancy stage, and more studies using animal models mimicking human TB are advocated to assess the role of miRNAs as biomarkers and therapeutic targets. In this review, we attempt to summarize the recent advancements in the role of miRNAs in TB as immune modulator, miRNAs' capability to distinguish between active and latent TB and, finally, usage of miRNAs as therapeutic targets against TB.

17.
J Parasit Dis ; 42(1): 96-101, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29491567

RESUMO

Trypanosomiasis is an important protozoal disease with a diverse range of susceptible host including human. In the current study, molecular characterization of prevalent species was done through a pan-trypanosome polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP). A total of three hundred (n = 300) equines including horses, donkeys and mules (100 each) were randomly selected and the equine blood samples were subjected to screening for trypanosomes through microhaematocrit centrifuge technique (MHCT), conventional PCR, semi-nested PCR and RFLP. Overall prevalence of trypanosomal species was 8% (24/300) as revealed by MHCT and species wise prevalence in horses, donkeys and mules was 4.33% (13/300), 1.33% (4/300) and 2.33% (7/300), respectively. Conventional and semi-nested PCR depicted an overall prevalence of 21% (63/300) and species wise prevalence in horses, donkeys and mules was 12% (36/300), 3.67% (11/300) and 5.33% (16/300), respectively. RFLP analysis of the semi-nested products, using Msp1 and Eco571 enzymes, negated the presence of T. congolense, T. brucei, T. vivax, T. theileri, and T. vivax in the positive samples and revealed that the animals might be suffering from T. evansi infection as the enzymes used were not able to detect this species. This hypothesis was further confirmed by using T. evansi specific primers which depicted all of the 63 samples were positive for T. evansi. It is inferred that T. evansi is the major trypanosome species prevalent in equines. Furthermore, PCR is more sensitive as compared to microscopic examination and the pan-trypanosome PCR-RFLP assay is suitable for carrying out laboratory diagnosis of field samples and epidemiological studies. Further studies on the possibilities of use of other restriction enzymes may help to improve the species specificity of the assay.

18.
Int J Mol Sci ; 18(12)2017 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-29258190

RESUMO

Tuberculosis (TB) is a major health threat to the human population worldwide. The etiology of the disease is Mycobacterium tuberculosis (Mtb), a highly successful intracellular pathogen. It has the ability to manipulate the host immune response and to make the intracellular environment suitable for its survival. Many studies have addressed the interactions between the bacteria and the host immune cells as involving many immune mediators and other cellular players. Interferon-ß (IFN-ß) signaling is crucial for inducing the host innate immune response and it is an important determinant in the fate of mycobacterial infection. The role of IFN-ß in protection against viral infections is well established and has been studied for decades, but its role in mycobacterial infections remains much more complicated and debatable. The involvement of IFN-ß in immune evasion mechanisms adopted by Mtb has been an important area of investigation in recent years. These advances have widened our understanding of the pro-bacterial role of IFN-ß in host-pathogen interactions. This pro-bacterial activity of IFN-ß appears to be correlated with its anti-inflammatory characteristics, primarily by antagonizing the production and function of interleukin 1ß (IL-1ß) and interleukin 18 (IL-18) through increased interleukin 10 (IL-10) production and by inhibiting the nucleotide-binding domain and leucine-rich repeat protein-3 (NLRP3) inflammasome. Furthermore, it also fails to provoke a proper T helper 1 (Th1) response and reduces the expression of major histocompatibility complex II (MHC-II) and interferon-γ receptors (IFNGRs). Here we will review some studies to provide a paradigm for the induction, regulation, and role of IFN-ß in mycobacterial infection. Indeed, recent studies suggest that IFN-ß plays a role in Mtb survival in host cells and its downregulation may be a useful therapeutic strategy to control Mtb infection.


Assuntos
Interferon beta/metabolismo , Tuberculose/metabolismo , Animais , Interações Hospedeiro-Patógeno , Humanos , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
19.
Oncotarget ; 8(19): 31938-31947, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28404882

RESUMO

Bovine protothecal mastitis results in considerable economic losses worldwide. However, Prototheca zopfii induced morphological alterations and oxidative stress in bovine mammary epithelial cells (bMECs) is not comprehensively studied yet. Therefore, the aim of this current study was to investigate the P. zopfii induced pathomorphological changes, oxidative stress and apoptosis in bMECs. Oxidative stress was assessed by evaluating catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), malondialdehyde (MDA) contents and lactate dehydrogenase (LDH) activity, while ROS generation and apoptosis was measured by confocal laser scanning microscopy. The results revealed that infection of P. zopfii genotype II (GTII) significantly changed bMECs morphology, increased apoptotic rate and MDA contents at 12 h (p < 0.05) and 24 h (p < 0.01) in comparison with control group, in time-dependent manner. LDH activity and ROS generation was also increased (p < 0.01) at 12 h and 24 h. However, SOD and CAT contents in bMECs infected with GTII were decreased (p < 0.05) at 12 h, while GPx (p < 0.01), SOD (p < 0.05) and CAT (p < 0.01) levels were reduced at 24 h. In case of GTI, only CAT and GPx activities were significantly decreased when the duration prolonged to 24 h but lesser than GTII. This suggested that GTII has more devastating pathogenic effects in bMECs, and the findings of this study concluded that GTII induced apoptosis and oxidative stress in bMECs via the imbalance of oxidant and antioxidant defenses as well as the production of intracellular ROS.


Assuntos
Apoptose , Células Epiteliais/metabolismo , Mastite Bovina/metabolismo , Mastite Bovina/microbiologia , Estresse Oxidativo , Prototheca , Animais , Biomarcadores , Bovinos , Feminino , L-Lactato Desidrogenase/metabolismo , Malondialdeído/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo
20.
Front Immunol ; 8: 1915, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29375563

RESUMO

Mycobacterium avium subspecies paratuberculosis (MAP) persistently survive and replicate in mononuclear phagocytic cells by adopting various strategies to subvert host immune response. Interleukin-10 (IL-10) upregulation via inhibition of macrophage bactericidal activity is a critical step for MAP survival and pathogenesis within the host cell. Mitogen-activated protein kinase p38 signaling cascade plays a crucial role in the elevation of IL-10 and progression of MAP pathogenesis. The contribution of microRNAs (miRNAs) and their influence on the activation of macrophages during MAP pathogenesis are still unclear. In the current study, we found that miRNA-27a-3p (miR-27a) expression is downregulated during MAP infection both in vivo and in vitro. Moreover, miR-27a is also downregulated in toll-like receptor 2 (TLR2)-stimulated murine macrophages (RAW264.7 and bone marrow-derived macrophage). ELISA and real-time qRT-PCR results confirm that overexpression of miR-27a inhibited MAP-induced IL-10 production in macrophages and upregulated pro-inflammatory cytokines, while miR-27a inhibitor counteracted these effects. Luciferase reporter assay results revealed that IL-10 and TGF-ß-activated protein kinase 1 binding protein 2 (TAB 2) are potential targets of miR-27a. In addition, we demonstrated that miR-27a negatively regulates TAB 2 expression and diminishes TAB 2-dependent p38/JNK phosphorylation, ultimately downregulating IL-10 expression in MAP-infected macrophages. Furthermore, overexpression of miR-27a significantly inhibited the intracellular survival of MAP in infected macrophages. Our data show that miR-27a augments antimicrobial activities of macrophages and inhibits the expression of IL-10, demonstrating that miR-27a regulates protective innate immune responses during MAP infection and can be exploited as a novel therapeutic target in the control of intracellular pathogens, including paratuberculosis.

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