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1.
J Immunol ; 200(2): 523-537, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29229678

RESUMO

Sarcoplasmic/endoplasmic reticulum Ca2+ adenosine triphosphatase (SERCA)2a, a critical regulator of calcium homeostasis, is known to be decreased in heart failure. Patients with myocarditis or dilated cardiomyopathy develop autoantibodies to SERCA2a suggesting that they may have pathogenetic significance. In this report, we describe epitope mapping analysis of SERCA2a in A/J mice that leads us to make five observations: 1) SERCA2a contains multiple T cell epitopes that induce varying degrees of myocarditis. One epitope, SERCA2a 971-990, induces widespread atrial inflammation without affecting noncardiac tissues; the cardiac abnormalities could be noninvasively captured by echocardiography, electrocardiography, and magnetic resonance microscopy imaging. 2) SERCA2a 971-990-induced disease was associated with the induction of CD4 T cell responses and the epitope preferentially binds MHC class II/IAk rather than IEk By creating IAk/and IEk/SERCA2a 971-990 dextramers, the T cell responses were determined by flow cytometry to be Ag specific. 3) SERCA2a 971-990-sensitized T cells produce both Th1 and Th17 cytokines. 4) Animals immunized with SERCA2a 971-990 showed Ag-specific Abs with enhanced production of IgG2a and IgG2b isotypes, suggesting that SERCA2a 971-990 can potentially act as a common epitope for both T cells and B cells. 5) Finally, SERCA2a 971-990-sensitized T cells were able to transfer disease to naive recipients. Together, these data indicate that SERCA2a is a critical autoantigen in the mediation of atrial inflammation in mice and that our model may be helpful to study the inflammatory events that underlie the development of conditions such as atrial fibrillation in humans.


Assuntos
Mapeamento de Epitopos , Epitopos/imunologia , Miocardite/imunologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/imunologia , Alelos , Animais , Proteínas de Bactérias , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Mapeamento de Epitopos/métodos , Epitopos de Linfócito B/imunologia , Imunofluorescência , Expressão Gênica , Átrios do Coração/imunologia , Átrios do Coração/metabolismo , Átrios do Coração/patologia , Ventrículos do Coração/imunologia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Epitopos Imunodominantes/imunologia , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos , Miocardite/diagnóstico por imagem , Miocardite/patologia , Miócitos Cardíacos/imunologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Peptídeos/imunologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
2.
Angiogenesis ; 20(1): 55-71, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27743086

RESUMO

Hypoxia is a feature of all solid tumours, contributing to tumour progression. Activation of HIF-1α plays a critical role in promoting tumour angiogenesis and metastasis. Since its expression is positively correlated with poor prognosis for cancer patients, HIF-1α is one of the most convincing anticancer targets. BP-1T is a novel antiproliferative agent with promising antiangiogenic effects. In the present study, the molecular mechanism underlying cytotoxic/antiangiogenic effects of BP-1T on tumour/non-tumour angiogenesis was evaluated. Evidences show that BP-1T exhibits potent cytotoxicity with prolonged activity and effectively regressed neovessel formation both in reliable non-tumour and tumour angiogenic models. The expression of CoCl2-induced HIF-1α was inhibited by BP-1T in various p53 (WT)-expressing cancer cells, including A549, MCF-7 and DLA, but not in mutant p53-expressing SCC-9 cells. Mechanistically, BP-1T mediates the HIF-1α proteasomal degradation by activating p53/MDM2 pathway and thereby downregulated HIF-1α-dependent angiogenic genes such as VEGF-A, Flt-1, MMP-2 and MMP-9 under hypoxic condition of in vitro and in vivo solid tumour, eventually leading to abolition of migration and invasion. Based on these observations, we conclude that BP-1T acts on HIF-1α degradation through p53/MDM2 proteasome pathway.


Assuntos
Inibidores da Angiogênese/farmacologia , Benzofenonas/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Tiazóis/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Benzofenonas/química , Carcinogênese/metabolismo , Carcinogênese/patologia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Camundongos , Microvasos/patologia , Modelos Biológicos , Neovascularização Fisiológica/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos , Tiazóis/química
3.
Biochem Biophys Res Commun ; 484(1): 85-92, 2017 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-28104392

RESUMO

Neoplastic cells often reside in distinctive tumor hypoxia armed with a series of adaptive responses including oxidative stress, defective apoptotic machinery and neoangiogenesis, through that further confer cell survival improvement. Plants still acts as reservoir of natural chemicals to provide newer active pharmacophores. Scutellarein is flavones which has wide range of pharmacophoral effects. In our current research, scutellarein employed for targeting oxidative stress mediated tumor angiogenesis and apoptotic nuclear fragmentation. Experimental results revealed that scutellarein has antiproliferative index against multiple cancer cell lines and diminished the oxidative stress and tumor development of murine ascitic lymphoma & inflammatory hepatocellular carcinoma. Eventual consequences lead to reduced neovessel formation by abrogating angiogeneic factors cytokine-VEGF-A, Flt-1, HIF-1α, MMP-2 and MMP-9 and reversing of evading apoptosis by activating caspase-3 activated DNA fragmentation factor (DFF-40) mediated nucleosomal degradation. In summary, our experimental evidences suggest that scutellarein has strong potentiality to attenuate the tumor development by modulating sprouting neovasculature and DFF-40 mediated apoptosis.


Assuntos
Apigenina/farmacologia , Carcinogênese/efeitos dos fármacos , Desoxirribonucleases/farmacologia , Neovascularização Patológica/induzido quimicamente , Nucleossomos/metabolismo , Fator A de Crescimento do Endotélio Vascular/fisiologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Ratos
4.
Am J Pathol ; 186(12): 3160-3175, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27876151

RESUMO

Heart failure, a leading cause of death in humans, can emanate from myocarditis. Although most individuals with myocarditis recover spontaneously, some develop chronic dilated cardiomyopathy. Myocarditis may result from both infectious and noninfectious causes, including autoimmune responses to cardiac antigens. In support of this notion, intracellular cardiac antigens, like cardiac myosin heavy chain-α, cardiac troponin-I, and adenine nucleotide translocator 1 (ANT1), have been identified as autoantigens in cardiac autoimmunity. Herein, we demonstrate that ANT1 can induce autoimmune myocarditis in A/J mice by generating autoreactive T cells. We show that ANT1 encompasses multiple immunodominant epitopes (namely, ANT1 21-40, ANT1 31-50, ANT1 171-190, and ANT1 181-200). Although all four peptides induce comparable T-cell responses, only ANT1 21-40 was found to be a major myocarditogenic epitope in immunized animals. The myocarditis-inducing ability of ANT1 21-40 was associated with the generation of T cells producing predominantly IL-17A, and the antigen-sensitized T cells could transfer the disease to naïve recipients. These data indicate that cardiac mitochondrial proteins can be target autoantigens in myocarditis, supporting the notion that the antigens released as a result of primary damage may contribute to the persistence of chronic inflammation through autoimmunity.


Assuntos
Translocador 1 do Nucleotídeo Adenina/imunologia , Autoantígenos/imunologia , Cardiomiopatia Dilatada/fisiopatologia , Miocardite/imunologia , Translocador 1 do Nucleotídeo Adenina/metabolismo , Animais , Miosinas Cardíacas/metabolismo , Cardiomiopatia Dilatada/etiologia , Epitopos , Feminino , Coração/fisiopatologia , Humanos , Inflamação , Interleucina-17/metabolismo , Camundongos , Proteínas Mitocondriais/imunologia , Proteínas Mitocondriais/metabolismo , Miocardite/complicações , Miocardite/fisiopatologia , Linfócitos T/imunologia , Troponina I/imunologia
5.
BMC Genomics ; 17 Suppl 7: 511, 2016 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-27557119

RESUMO

BACKGROUND: We recently reported the identification of Bacillus sp. NRRL B-14911 that induces heart autoimmunity by generating cardiac-reactive T cells through molecular mimicry. This marine bacterium was originally isolated from the Gulf of Mexico, but no associations with human diseases were reported. Therefore, to characterize its biological and medical significance, we sought to determine and analyze the complete genome sequence of Bacillus sp. NRRL B-14911. RESULTS: Based on the phylogenetic analysis of 16S ribosomal RNA (rRNA) genes, sequence analysis of the 16S-23S rDNA intergenic transcribed spacers, phenotypic microarray, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry, we propose that this organism belongs to the species Bacillus infantis, previously shown to be associated with sepsis in a newborn child. Analysis of the complete genome of Bacillus sp. NRRL B-14911 revealed several virulence factors including adhesins, invasins, colonization factors, siderophores and transporters. Likewise, the bacterial genome encodes a wide range of methyl transferases, transporters, enzymatic and biochemical pathways, and insertion sequence elements that are distinct from other closely related bacilli. CONCLUSIONS: The complete genome sequence of Bacillus sp. NRRL B-14911 provided in this study may facilitate genetic manipulations to assess gene functions associated with bacterial survival and virulence. Additionally, this bacterium may serve as a useful tool to establish a disease model that permits systematic analysis of autoimmune events in various susceptible rodent strains.


Assuntos
Bacillus/genética , Genoma Bacteriano/genética , Coração/microbiologia , Miocárdio/imunologia , Bacillus/patogenicidade , Genômica , Coração/fisiopatologia , Humanos , Anotação de Sequência Molecular , Miocárdio/patologia , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Reprod Domest Anim ; 49(3): 403-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24612212

RESUMO

Interferon-τ (IFN-τ) has been recognized as the primary embryonic signal responsible for maternal recognition of pregnancy. Uterine endometrium produces both prostaglandin F2α (PGF2α ) and prostaglandin E2 (PGE2 ). PGF2α is responsible for the luteolysis; however, PGE2 favours establishment of pregnancy by its luteoprotective action. In this study, the dose-response effect of recombinant bovine IFN-τ (rbIFN-τ) on prostaglandin (PG) production by buffalo endometrial stromal cells cultured in vitro was studied. Buffalo endometrial stromal cells were isolated by double enzymatic digestion, initially with trypsin III followed by a cocktail of trypsin III, collagenase type II and DNase I and subsequently cultured till confluence. Further, cells were treated with different doses of rbIFN-τ (0.001, 0.01, 0.1, 1.0 and 10 µg/ml) and keeping a separate set of control. Culture supernatant was collected after 6, 12 and 24 h of treatment. PG levels in the culture supernatant were measured by enzyme immune assay (EIA) and total cellular protein estimated by Bradford method. Results indicated that buffalo endometrial stromal cells following rbIFN-τ treatment enhanced the secretion of both PGE2 and PGF2α , and also its ratio in a strict dose-dependent manner with a significant increase (p < 0.01) in PGE2 production at 1 µg/ml dose of rbIFN-τ and maximal stimulation for both PG was observed at 10 µg/ml. Further, both PG production and its ratio were increased significantly (p < 0.01) in a time-dependent fashion in all the groups at 6, 12 and 24 h post-treatment with highest level achieved at 24 h as compared with control. Absolute levels of PGE2 remained higher than PGF2α indicating PGE2 as the major PG produced by endometrial stromal cells. The dose-dependent response of rbIFN-τ signifies the importance of optimum concentration of IFN-τ for the embryonic development especially during the critical period to establish successful pregnancy.


Assuntos
Búfalos , Endométrio/citologia , Interferon Tipo I/farmacologia , Proteínas da Gravidez/farmacologia , Prostaglandinas/biossíntese , Células Estromais/metabolismo , Animais , Bovinos , Células Cultivadas , Dinoprosta/análise , Dinoprosta/biossíntese , Dinoprostona/análise , Dinoprostona/biossíntese , Feminino , Gravidez , Proteínas Recombinantes/farmacologia , Células Estromais/efeitos dos fármacos
7.
Cureus ; 15(8): e42901, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37664253

RESUMO

Scrub typhus is a vector-borne disease caused by gram-negative bacilli, Orientia tsutsugamushi. The vector of scrub typhus is the mite. The clinical manifestations often present with either a simple fever or life-threatening multi-organ dysfunction. Neurological manifestations also vary, and the incidence of neurological manifestations is unknown. Cerebellitis is one of the rare neurological manifestations associated with scrub typhus. In this case report, we present the case of a 35-year-old man who tested positive for scrub typhus (IgM enzyme-linked immunosorbent assay (ELISA) blood test) with a history of fever and cerebellar signs and symptoms. He was managed with antibacterial agents and made a good recovery.

8.
Neuropharmacology ; 220: 109239, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36126727

RESUMO

Cocaine abuse increases the incidence of HIV-1-associated neurocognitive disorders. We have demonstrated that HIV-1 transactivator of transcription (Tat) allosterically modulates dopamine (DA) reuptake through the human DA transporter (hDAT), potentially contributing to Tat-induced cognitive impairment and potentiation of cocaine conditioned place preference (CPP). This study determined the effects of a novel allosteric modulator of DAT, SRI-32743, on the interactions of HIV-1 Tat, DA, cocaine, and [3H]WIN35,428 with hDAT in vitro. SRI-32743 (50 nM) attenuated Tat-induced inhibition of [3H]DA uptake and decreased the cocaine-mediated dissociation of [3H]WIN35,428 binding in CHO cells expressing hDAT, suggesting a SRI-32743-mediated allosteric modulation of the Tat-DAT interaction. In further in vivo studies utilizing doxycycline-inducible Tat transgenic (iTat-tg) mice, 14 days of Tat expression significantly reduced the recognition index by 31.7% in the final phase of novel object recognition (NOR) and potentiated cocaine-CPP 2.7-fold compared to responses of vehicle-treated control iTat-tg mice. The Tat-induced NOR deficits and potentiation of cocaine-CPP were not observed in saline-treated iTat-tg or doxycycline-treated G-tg (Tat-null) mice. Systemic administration (i.p.) of SRI-32743 prior to behavioral testing ameliorated Tat-induced impairment of NOR (at a dose of 10 mg/kg) and the Tat-induced potentiation of cocaine-CPP (at doses of 1 or 10 mg/kg). These findings demonstrate that Tat and cocaine interactions with DAT may be regulated by compounds interacting at the DAT allosteric modulatory sites, suggesting a potential therapeutic intervention for HIV-infected patients with concurrent cocaine abuse.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Cocaína , HIV-1 , Animais , Cocaína/metabolismo , Cocaína/farmacologia , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Cricetinae , Cricetulus , Dopamina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Doxiciclina , Humanos , Camundongos , Camundongos Transgênicos , Recompensa , Transativadores , Fator de Transcrição DP1/metabolismo , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética
9.
Sci Rep ; 11(1): 12432, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127684

RESUMO

Coxsackievirus B3 (CVB3), is commonly implicated in myocarditis, which can lead to dilated cardiomyopathy, in addition to causing acute pancreatitis and meningitis. Yet, no vaccines are currently available to prevent this infection. Here, we describe the derivation of a live attenuated vaccine virus, termed mutant (Mt) 10, encoding a single amino acid substitution H790A within the viral protein 1, that prevents CVB3 infection in mice and protects from both myocarditis and pancreatitis in challenge studies. We noted that animals vaccinated with Mt 10 developed virus-neutralizing antibodies, predominantly containing IgG2a and IgG2b, and to a lesser extent IgG3 and IgG1. Furthermore, by using major histocompatibility complex class II dextramers and tetramers, we demonstrated that Mt 10 induces antigen-specific T cell responses that preferentially produce interferon-γ. Finally, neither vaccine recipients nor those challenged with the wild-type virus revealed evidence of autoimmunity or cardiac injury as determined by T cell response to cardiac myosin and measurement of circulating cardiac troponin I levels, respectively. Together, our data suggest that Mt 10 is a vaccine candidate that prevents CVB3 infection through the induction of neutralizing antibodies and antigen-specific T cell responses, the two critical components needed for complete protection against virus infections in vaccine studies.


Assuntos
Infecções por Coxsackievirus/prevenção & controle , Enterovirus Humano B/imunologia , Miocardite/prevenção & controle , Pancreatite/prevenção & controle , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Antígenos Virais/imunologia , Sítios de Ligação/genética , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/metabolismo , Infecções por Coxsackievirus/virologia , Modelos Animais de Doenças , Enterovirus Humano B/genética , Feminino , Humanos , Imunogenicidade da Vacina/genética , Masculino , Camundongos , Mutação , Miocardite/virologia , Pancreatite/virologia , Linfócitos T/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
10.
Cancer Res ; 81(8): 2220-2233, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33602784

RESUMO

The development of novel therapeutics that exploit alterations in the activation state of key cellular signaling pathways due to mutations in upstream regulators has generated the field of personalized medicine. These first-generation efforts have focused on actionable mutations identified by deep sequencing of large numbers of tumor samples. We propose that a second-generation opportunity exists by exploiting key downstream "nodes of control" that contribute to oncogenesis and are inappropriately activated due to loss of upstream regulation and microenvironmental influences. The RNA-binding protein HuR represents such a node. Because HuR functionality in cancer cells is dependent on HuR dimerization and its nuclear/cytoplasmic shuttling, we developed a new class of molecules targeting HuR protein dimerization. A structure-activity relationship algorithm enabled development of inhibitors of HuR multimer formation that were soluble, had micromolar activity, and penetrated the blood-brain barrier. These inhibitors were evaluated for activity validation and specificity in a robust cell-based assay of HuR dimerization. SRI-42127, a molecule that met these criteria, inhibited HuR multimer formation across primary patient-derived glioblastoma xenolines (PDGx), leading to arrest of proliferation, induction of apoptosis, and inhibition of colony formation. SRI-42127 had favorable attributes with central nervous system penetration and inhibited tumor growth in mouse models. RNA and protein analysis of SRI-42127-treated PDGx xenolines across glioblastoma molecular subtypes confirmed attenuation of targets upregulated by HuR. These results highlight how focusing on key attributes of HuR that contribute to cancer progression, namely cytoplasmic localization and multimerization, has led to the development of a novel, highly effective inhibitor. SIGNIFICANCE: These findings utilize a cell-based mechanism of action assay with a structure-activity relationship compound development pathway to discover inhibitors that target HuR dimerization, a mechanism required for cancer promotion.


Assuntos
Carcinogênese/efeitos dos fármacos , Proteína Semelhante a ELAV 1/química , Multimerização Proteica/efeitos dos fármacos , Algoritmos , Animais , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteína Semelhante a ELAV 1/metabolismo , Proteína Semelhante a ELAV 1/fisiologia , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Camundongos , Camundongos Nus , Medicina de Precisão , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Ensaio Tumoral de Célula-Tronco , Regulação para Cima
11.
J Environ Health ; 73(2): 22-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20873529

RESUMO

The dilution rates of indicators Enterococcus faecalis and E. coli were studied from the St. John's River estuary in Grenada, West Indies. Health risk zones were established based on the levels of bacteriological pollution. In accordance with the World Health Organization (WHO) health risk guidelines, risks were in the range of <1% gastrointestinal (GI); <0.3% acute febrile respiratory illness (AFRI) to a 1%-5% GI; and 0.9%-1.9% AFRI within 100 m from the St. John's River outflow site in St. George's Bay. These values were the result of river water dilution, where the most probable number (MPN) levels for both indicator organisms from the river were equivalent to that of raw sewage with an AFRI health risk of >3.9% and a GI risk of >10%. The distance intervals farther than 100 m showed fluctuating values and corresponding health risks. E. faecalis and E. coli strains isolated were resistant to 35.7% and 42.9% of the antibiotics tested, respectively.


Assuntos
Eutrofização , Água do Mar/microbiologia , Esgotos/microbiologia , Eliminação de Resíduos Líquidos , Microbiologia da Água , Poluição da Água , Contagem de Colônia Microbiana , Enterococcus faecalis/isolamento & purificação , Escherichia coli/isolamento & purificação , Granada , Humanos , Testes de Sensibilidade Microbiana
12.
J Pain ; 21(1-2): 146-160, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31201990

RESUMO

Numerous studies have demonstrated a physiological interaction between the mu opioid receptor (MOR) and delta opioid receptor (DOR) systems. A few studies have shown that dual MOR-DOR agonists could be beneficial, with reduced tolerance and addiction liability, but are nearly untested in chronic pain models, particularly neuropathic pain. In this study, we tested the MOR-DOR agonist SRI-22141 in mice in the clinically relevant models of HIV Neuropathy and Chemotherapy-Induced Peripheral Neuropathy (CIPN). SRI-22141 was more potent than morphine in the tail flick pain test and had equal or enhanced efficacy versus morphine in both neuropathic pain models, with significantly reduced tolerance. SRI-22141 also produced no jumping behavior during naloxone-precipitated withdrawal in CIPN or naïve mice, suggesting that SRI-22141 produces little to no dependence. SRI-22141 also reduced tumor necrosis factor-α and cyclooxygenase-2 in CIPN in the spinal cord, suggesting an anti-inflammatory mechanism of action. The DOR-selective antagonist naltrindole strongly reduced CIPN efficacy and anti-inflammatory activity in the spinal cord, without affecting tail flick antinociception, suggesting the importance of DOR activity in these models. Overall, these results provide compelling evidence that MOR-DOR agonists could have strong efficacy with reduced side effects and an anti-inflammatory mechanism in the treatment of neuropathic pain. PERSPECTIVE: This study demonstrates that a MOR-DOR dual agonist given chronically in chronic neuropathic pain models has enhanced efficacy with strongly reduced tolerance and dependence, with a further anti-inflammatory effect in the spinal cord. This suggests that MOR-DOR dual agonists could be effective treatments for neuropathic pain with reduced side effects.


Assuntos
Analgésicos Opioides/farmacologia , Anti-Inflamatórios/farmacologia , Comportamento Animal/efeitos dos fármacos , Neuralgia/tratamento farmacológico , Receptores Opioides delta/agonistas , Receptores Opioides mu/agonistas , Nefropatia Associada a AIDS/tratamento farmacológico , Animais , Linhagem Celular , Cricetulus , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR , Síndromes Neurotóxicas/tratamento farmacológico , Ovário
13.
Mol Immunol ; 124: 218-228, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32615275

RESUMO

Autoreactive T cells may contribute to post-viral myocarditis induced with Coxsackievirus B3 (CVB3), but the underlying mechanisms of their generation are unclear. Here, we have comprehensively analyzed the generation of antigen-specific, autoreactive T cells in the mouse model of CVB3 infection for antigens implicated in patients with myocarditis/dilated cardiomyopathy. First, comparative analysis of CVB3 proteome with five autoantigens led us to identify three mimicry epitopes, one each from adenine nucleotide translocator 1 (ANT), sarcoplasmic/endoplasmic reticulum Ca2+ ATPase 2a (SERCA2a) and cardiac troponin I. None of these induced cross-reactive T cell responses. Next, we generated major histocompatibility complex (MHC) class II dextramers to enumerate the frequencies of antigen-specific T cells to determine whether T cells with multiple antigen specificities are generated by CVB3 infection. These analyses revealed appearance of CD4 T cells positive for SERCA2a 971-990, and cardiac myosin heavy chain-α (Myhc) 334-352 dextramers, both in the periphery and also in the hearts of CVB3-infected animals. While ANT 21-40 dextramer+ T cells were inconsistently detected, the ß1-adrenergic receptor 181-200/211-230 or branched chain α-ketoacid dehydrogenase kinase 111-130 dextramer+ cells were absent. Interestingly, SERCA2a 971-990, Myhc 334-352 and ANT 21-40 dextramer+ cells were also detected in the liver indicating that they may have a pathogenic role. Finally, we demonstrate that the SERCA2a 971-990-reactive T cells generated in CVB3 infection could transfer disease to naïve mice. The data suggest that CVB3 infection can lead to the generation of autoreactive T cells for multiple antigens indicating a possibility that the autoreactive T cells localized in the liver can potentially circulate and contribute to the development of viral myocarditis.


Assuntos
Autoantígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções por Coxsackievirus/imunologia , Miocardite/imunologia , Miocardite/virologia , Animais , Autoimunidade/imunologia , Reações Cruzadas , Modelos Animais de Doenças , Enterovirus Humano B , Feminino , Masculino , Camundongos
14.
J Med Chem ; 63(14): 7663-7694, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32530286

RESUMO

We previously identified a pyridomorphinan (6, SRI-22138) possessing a 4-chlorophenyl substituent at the 5'-position on the pyridine and a 3-phenylpropoxy at the 14-position of the morphinan as a mixed µ opioid receptor (MOR) agonist and δ/κ opioid receptor (DOR/KOR) antagonist with potent antinociceptive activity and diminished tolerance and dependence in rodents. Structural variations at the 5'- and 14-positions of this molecule gave insights into the structure-activity relationships for binding and functional activity. Subtle structural changes exerted significant influence, particularly on the ability of the compounds to function as agonists at the MOR. In vivo evaluation identified compound 20 (SRI-39067) as a MOR agonist/DOR antagonist that produced systemically active potent antinociceptive activity in tail-flick assay in mice, with diminished tolerance, dependence/withdrawal, reward liability, and respiratory depression versus morphine. These results support the hypothesis that mixed MOR agonist/DOR antagonist ligands may emerge as novel opioid analgesics with reduced side effects.


Assuntos
Analgésicos Opioides/uso terapêutico , Morfinanos/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Piridinas/uso terapêutico , Receptores Opioides delta/antagonistas & inibidores , Receptores Opioides mu/agonistas , Analgésicos Opioides/síntese química , Analgésicos Opioides/metabolismo , Animais , Células CHO , Cricetulus , Desenho de Fármacos , Humanos , Masculino , Camundongos , Microssomos Hepáticos/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Morfinanos/síntese química , Morfinanos/metabolismo , Antagonistas de Entorpecentes/síntese química , Antagonistas de Entorpecentes/metabolismo , Ligação Proteica , Piridinas/síntese química , Piridinas/metabolismo , Receptores Opioides delta/metabolismo , Receptores Opioides mu/metabolismo , Relação Estrutura-Atividade
15.
Nucl Med Commun ; 29(2): 98-102, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18094630

RESUMO

Mobile PET/CT or mobile stand alone PET, is becoming more widely available throughout the developed world, allowing many small and medium-sized hospitals that do not have the scale or financial resources to purchase the static diagnostic equipment, to benefit from this imaging technology. Before embarking on such a service, a number of legislative, logistical and administrative issues have to be addressed to ensure that a mobile PET/CT service is run with optimal efficiency and safety and in compliance with the regulations governing the use of radioactive substances. Some of these issues are similar to those encountered in operating a mobile magnetic resonance imaging scanner but there are important differences owing to the use of both sealed and open radioactive sources. This article highlights the legislative, administrative and practical issues relevant to the UK and also discusses some of the practical issues that need to be addressed to ensure the operation of a safe and effective PET service.


Assuntos
Unidades Móveis de Saúde , Tomografia por Emissão de Pósitrons/instrumentação , Tomografia por Emissão de Pósitrons/métodos , Radiologia/economia , Radiologia/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Tomografia Computadorizada por Raios X/métodos , Análise Custo-Benefício , Fluordesoxiglucose F18/farmacologia , Hospitais , Humanos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Neoplasias/diagnóstico , Neoplasias/terapia , Radiologia/tendências , Fatores de Tempo , Reino Unido
16.
Artigo em Inglês | MEDLINE | ID: mdl-29515433

RESUMO

The dopamine D2 receptor (D2R) is known to elicit effects through activating two major signaling pathways mediated by either G proteins (Gi/o) or ß-arrestins. However, the specific role of each pathway in physiological or therapeutic activities is not known with certainty. One approach to the dissection of these pathways is through the use of drugs that can selectively modulate one pathway vs. the other through a mechanism known as functional selectivity or biased signaling. Our laboratory has previously described a G protein signaling-biased agonist, MLS1547, for the D2R using a variety of in vitro functional assays. To further evaluate the biased signaling activity of this compound, we investigated its ability to promote D2R internalization, a process known to be mediated by ß-arrestin. Using multiple cellular systems and techniques, we found that MLS1547 promotes little D2R internalization, which is consistent with its inability to recruit ß-arrestin. Importantly, we validated these results in primary striatal neurons where the D2R is most highly expressed suggesting that MLS1547 will exhibit biased signaling activity in vivo. In an effort to optimize and further explore structure-activity relationships (SAR) for this scaffold, we conducted an iterative chemistry campaign to synthesize and characterize novel analogs of MLS1547. The resulting analysis confirmed previously described SAR requirements for G protein-biased agonist activity and, importantly, elucidated new structural features that are critical for agonist efficacy and signaling bias of the MLS1547 scaffold. One of the most important determinants for G protein-biased signaling is the interaction of a hydrophobic moiety of the compound with a defined pocket formed by residues within transmembrane five and extracellular loop two of the D2R. These results shed new light on the mechanism of biased signaling of the D2R and may lead to improved functionally-selective molecules.

17.
Front Immunol ; 8: 1567, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29209317

RESUMO

Myocarditis/dilated cardiomyopathy (DCM) patients can develop autoantibodies to various cardiac antigens and one major antigen is ß1-adrenergic receptor (ß1AR). Previous reports indicate that animals immunized with a ß1AR fragment encompassing, 197-222 amino acids for a prolonged period can develop DCM by producing autoantibodies, but existence of T cell epitopes, if any, were unknown. Using A/J mice that are highly susceptible to lymphocytic myocarditis, we have identified ß1AR 171-190, ß1AR 181-200, and ß1AR 211-230 as the major T cell epitopes that bind major histocompatibility complex class II/IAk or IEk alleles, and by creating IAk and IEk dextramers, we demonstrate that the CD4 T cell responses to be antigen-specific. Of note, all the three epitopes were found also to stimulate CD8 T cells suggesting that they can act as common epitopes for both CD4 and CD8 T cells. While, all epitopes induced only mild myocarditis, the disease-incidence was enhanced in animals immunized with all the three peptides together as a cocktail. Although, antigen-sensitized T cells produced mainly interleukin-17A, their transfer into naive animals yielded no disease. But, steering for T helper 1 response led the T cells reacting to one epitope, ß1AR 181-200 to induce severe myocarditis in naive mice. Finally, we demonstrate that all three ß1AR epitopes to be unique for T cells as none of them induced antibody responses. Conversely, animals immunized with a non-T cell activator, ß1AR 201-220, an equivalent of ß1AR 197-222, had antibodies comprising of all IgG isotypes and IgM except, IgA and IgE. Thus, identification of T cell and B cell epitopes of ß1AR may be helpful to determine ß1AR-reactive autoimmune responses in various experimental settings in A/J mice.

18.
Immun Inflamm Dis ; 5(4): 421-434, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28597552

RESUMO

INTRODUCTION: Organ-specific autoimmune diseases are believed to result from immune responses generated against self-antigens specific to each organ. However, when such responses target antigens expressed promiscuously in multiple tissues, then the immune-mediated damage may be wide spread. METHODS: In this report, we describe a mitochondrial protein, branched chain α-ketoacid dehydrogenase kinase (BCKDk ) that can act as a target autoantigen in the development of autoimmune inflammatory reactions in both heart and liver. RESULTS: We demonstrate that BCKDk protein contains at least nine immunodominant epitopes, three of which, BCKDk 71-90, BCKDk 111-130 and BCKDk 141-160, were found to induce varying degrees of myocarditis in immunized mice. One of these, BCKDk 111-130, could also induce hepatitis without affecting lungs, kidneys, skeletal muscles, and brain. In immunogenicity testing, all three peptides induced antigen-specific T cell responses, as verified by proliferation assay and/or major histocompatibility complex class II/IAk dextramer staining. Finally, the disease-inducing abilities of BCKDk peptides were correlated with the production of interferon-γ, and the activated T cells could transfer disease to naive recipients. CONCLUSIONS: The disease induced by BCKDk peptides could serve as a useful model to study the autoimmune events of inflammatory heart and liver diseases.


Assuntos
Doenças Autoimunes/imunologia , Epitopos de Linfócito T/imunologia , Hepatite Autoimune/imunologia , Miocardite/imunologia , Proteínas Quinases/imunologia , Sequência de Aminoácidos , Animais , Autoantígenos/química , Autoantígenos/imunologia , Doenças Autoimunes/patologia , Biópsia , Citocinas/metabolismo , Modelos Animais de Doenças , Epitopos de Linfócito T/química , Hepatite Autoimune/patologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Imunização , Camundongos , Miocardite/patologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Proteínas Quinases/química , Multimerização Proteica , Linfócitos T/imunologia , Linfócitos T/metabolismo
19.
Org Lett ; 18(15): 3534-7, 2016 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-27458880

RESUMO

The intermolecular Friedel-Crafts acylation was carried out in hexafluoro-2-propanol to yield aryl and heteroaryl ketones at room temperature without any additional reagents.

20.
Theriogenology ; 85(3): 361-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26435261

RESUMO

During the last wave of the interovulatory interval (IOI), the permutations of the relationship between the ovulatory follicle and the CL (ipsilateral vs. contralateral) and the number of follicular waves (two vs. three) per IOI differ in frequency of occurrence as follows: ipsilateral relationship and two waves (34%), contralateral relationship and two waves (34%), ipsilateral relationship and three waves (8%), and contralateral relationship and three waves (24%). Deviation or the continuation in growth rate of the future ovulatory follicle and a decrease in growth rate of the future subordinate follicles begin well before luteolysis in two-wave IOIs and during luteolysis in three-wave IOIs. The largest follicle decreases in diameter and loses its dominant status before completion of deviation when it is ipsilateral and adjacent to the regressing CL during wave 3. Dominant status switches from the largest follicle in the ipsilateral ovary to the next-largest follicle which may be in either ovary. Switching accounts for the greater frequency of a contralateral follicle-CL relationship than for ipsilateral follicle-CL relationship during the ovulatory wave in three-wave IOIs. It is proposed that the phenomenon results from commonality in angioarchitecture so that the decrease in blood flow to the regressing CL is associated with a decrease in blood flow to adjacent follicles.


Assuntos
Bovinos/fisiologia , Corpo Lúteo/fisiologia , Folículo Ovariano/fisiologia , Animais , Corpo Lúteo/irrigação sanguínea , Feminino , Hormônio Foliculoestimulante/sangue , Luteólise/fisiologia , Folículo Ovariano/irrigação sanguínea , Ovulação/fisiologia , Progesterona/sangue
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