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1.
FASEB J ; 38(6): e23572, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38512139

RESUMO

Asthma is characterized by airway remodeling and hyperreactivity. Our earlier studies determined that the nitric oxide (NO)-soluble guanylyl cyclase (sGC)-cGMP pathway plays a significant role in human lung bronchodilation. However, this bronchodilation is dysfunctional in asthma due to high NO levels, which cause sGC to become heme-free and desensitized to its natural activator, NO. In order to determine how asthma impacts the various lung segments/lobes, we mapped the inflammatory regions of lungs to determine whether such regions coincided with molecular signatures of sGC dysfunction. We demonstrate using murine models of asthma (OVA and CFA/HDM) that the inflamed segments of these murine lungs can be tracked by upregulated expression of HO1 and these regions in turn overlap with regions of heme-free sGC as evidenced by a decreased sGC-α1ß1 heterodimer and an increased response to heme-independent sGC activator, BAY 60-2770, relative to naïve uninflamed regions. We also find that NO generated from iNOS upregulation in the inflamed segments has a higher impact on developing heme-free sGC as increasing iNOS activity correlates linearly with elevated heme-independent sGC activation. This excess NO works by affecting the epithelial lung hemoglobin (Hb) to become heme-free in asthma, thereby causing the Hb to lose its NO scavenging function and exposing the underlying smooth muscle sGC to excess NO, which in turn becomes heme-free. Recognition of these specific lung segments enhances our understanding of the inflamed lungs in asthma with the ultimate aim to evaluate potential therapies and suggest that regional and not global inflammation impacts lung function in asthma.


Assuntos
Asma , Heme Oxigenase-1 , Heme , Animais , Humanos , Camundongos , Alérgenos , Heme Oxigenase-1/metabolismo , Inflamação , Óxido Nítrico , Guanilil Ciclase Solúvel
2.
Int J Mol Sci ; 23(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35563330

RESUMO

The glucocorticoid receptor (GR) at the blood−brain barrier (BBB) is involved in the pathogenesis of drug-resistant epilepsy with focal cortical dysplasia (FCD); however, the roles of GR isoforms GRα and GRß in the dysplastic brain have not been revealed. We utilized dysplastic/epileptic and non-dysplastic brain tissue from patients who underwent resective epilepsy surgery to identify the GRα and GRß levels, subcellular localization, and cellular specificity. BBB endothelial cells isolated from the dysplastic brain tissue (EPI-ECs) were used to decipher the key BBB proteins related to drug regulation and BBB integrity compared to control and transfected GRß-overexpressed BBB endothelial cells. GRß was upregulated in dysplastic compared to non-dysplastic tissues, and an imbalance of the GRα/GRß ratio was significant in females vs. males and in patients > 45 years old. In EPI-ECs, the subcellular localization and expression patterns of GRß, Hsp90, CYP3A4, and CYP2C9 were consistent with GRß+ brain endothelial cells. Active matrix metalloproteinase levels and activity increased, whereas claudin-5 levels decreased in both EPI-ECs and GRß+ endothelial cells. In conclusion, the GRß has a major effect on dysplastic BBB functional proteins and is age and gender-dependent, suggesting a critical role of brain GRß in dysplasia as a potential biomarker and therapeutic target in epilepsy.


Assuntos
Epilepsia , Receptores de Glucocorticoides , Barreira Hematoencefálica , Encéfalo/metabolismo , Encéfalo/patologia , Células Endoteliais/metabolismo , Epilepsia/tratamento farmacológico , Epilepsia/metabolismo , Feminino , Glucocorticoides/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo
3.
Arch Gynecol Obstet ; 303(2): 419-426, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32897400

RESUMO

OBJECTIVE: Many modifiable maternal behaviors and experiences before and during pregnancy are associated with adverse health outcomes. The relationship between a number of maternal and gestational disorders and perinatal outcomes (preterm birth, low birth weight and neonatal intensive care unit (NICU)) admission in the Central New York population is determined using the Statewide Perinatal Data System, in a retrospective population-based cohort study. METHODS: Singleton births excluding newborns with congenital anomalies among 165,739 women between 2004 and 2012 are included in this study. Multivariable logistic regression analysis is used to estimate odds ratios (OR) and 95% confidence intervals (CI) adjusted for maternal age, race, education, employment, parity, body mass index, smoking, drug use, depression, abortions, gender of child, prenatal care, and hospital level. RESULTS: Previous preterm birth and vaginal bleeding are independent high-risk factors for all three perinatal outcomes, pre-pregnancy diabetes (OR 4.95, 95% CI 4.34, 5.64) for preterm birth and (OR 7.45, 95% CI 6.58, 8.44) for NICU admission; and gestational hypertension (OR 4.35, 95% CI 4.03, 4.70) for low birth weight. Among infections, bacterial vaginosis is retained in the multivariable model as a risk factor for preterm and low birth weight while hepatitis C is a risk factor for NICU admission. CONCLUSIONS: Our findings suggest the continued importance of addressing the need to provide preconception and inter conception care for women since many modifiable risk factors are correlated and need to be addressed well before the woman becomes pregnant.


Assuntos
Hipertensão Induzida pela Gravidez/epidemiologia , Recém-Nascido de Baixo Peso , Unidades de Terapia Intensiva Neonatal/estatística & dados numéricos , Pré-Eclâmpsia/epidemiologia , Gravidez em Diabéticas/epidemiologia , Nascimento Prematuro/epidemiologia , Adulto , Peso ao Nascer , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Idade Materna , Paridade , Gravidez , Cuidado Pré-Natal , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
4.
Andrologia ; 52(2): e13482, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31815317

RESUMO

Male infertility has become a global concern. Different conventional medicines with some side effects generally are used for the management of male infertility. To search out the potent aphrodisiac agent without side effect, an approach has been taken to prevent the cyproterone acetate (CPA)-treated male infertility by ethanolic extract of seed of Hygrophila auriculata in albino rat. CPA is used for the treatment of prostate cancer. It has anti-androgenic properties and suppresses the spermatogenesis process. Count, motility and viability of spermatozoa, number of hypo-osmotic tail swelled spermatozoa and serum testosterone level were significantly decreased in CPA-treated rat. CPA also caused significant diminution of activities of superoxide dismutase, catalase, peroxidase and elevation of malondialdehyde and conjugated dienes levels. All parameters were significantly restored after the treatment of H. auriculata extract to the CPA-treated rats. Histological study revealed significant rectification of seminiferous tubular diameter and spermatogenic cells in extract-treated group. Body weight, organo-somatic indices, serum glutamic oxaloacetic transaminase and serum glutamic pyruvic transaminase activities were significantly recovered towards control in H. auriculata-treated group. It is concluded that ethanolic extract of H. auriculata has androgenic and antioxidant properties that can improve male infertility without metabolic toxicity.


Assuntos
Acanthaceae , Infertilidade Masculina/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Testículo/efeitos dos fármacos , Animais , Acetato de Ciproterona , Avaliação Pré-Clínica de Medicamentos , Infertilidade Masculina/induzido quimicamente , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Extratos Vegetais/farmacologia , Ratos Wistar , Espermatozoides/efeitos dos fármacos , Espermatozoides/enzimologia , Testículo/enzimologia , Testículo/patologia , Testosterona/sangue
5.
Biochem Biophys Res Commun ; 507(1-4): 274-279, 2018 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-30449598

RESUMO

Breakdown of the blood-brain barrier (BBB) precedes lesion formation in the brains of multiple sclerosis (MS) patients. Since recent data implicate disruption of the small intestinal epithelial barrier (IEB) in the pathogenesis of MS, we hypothesized that the increased permeability of the BBB and IEB are mechanistically linked. Zonulin, a protein produced by small intestine epithelium, can rapidly increase small intestinal permeability. Zonulin blood levels are elevated in MS, but it is unknown whether zonulin can also disrupt the BBB. Increased production of IL-17A and IFN-γ has been implicated in the pathogenesis of MS, epilepsy, and stroke, and these cytokines impact BBB integrity after 24 h. We here report that primary human brain microvascular endothelial cells expressed the EGFR and PAR2 receptors necessary to respond to zonulin, and that zonulin increased BBB permeability to a 40 kDa dextran tracer within 1 h. Moreover, both IL-17A and IFN-γ also rapidly increased BBB and IEB permeability. By using confocal microscopy, we found that exposure of the IEB to zonulin, IFN-γ, or IL-17A in vitro rapidly modified the localization of the TJ proteins, ZO-1, claudin-5, and occludin. TJ disassembly was accompanied by marked depolymerization of the peri-junctional F-actin cytoskeleton. Our data indicate that IFN-γ, IL-17A, or zonulin can increase the permeability of the IEB and BBB rapidly in vitro, by modifying TJs and the underlying actin cytoskeleton. These observations may help clarify how the gut-brain axis mediates the pathogenesis of neuro-inflammatory diseases.


Assuntos
Barreira Hematoencefálica/patologia , Toxina da Cólera/farmacologia , Inflamação/patologia , Interferon gama/farmacologia , Interleucina-17/farmacologia , Mucosa Intestinal/patologia , Intestino Delgado/patologia , Barreira Hematoencefálica/efeitos dos fármacos , Impedância Elétrica , Haptoglobinas , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-17/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Permeabilidade , Precursores de Proteínas , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo
6.
Epilepsia ; 59(11): 2049-2060, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30264400

RESUMO

OBJECTIVE: Nuclear receptors and cytochrome P450 (CYP) regulate hepatic metabolism of several drugs. Nuclear receptors are expressed at the neurovascular unit of patients with drug-resistant epilepsy. We studied whether glucocorticoid receptor (GR) silencing or inhibition in human epileptic brain endothelial cells (EPI-ECs) functionally impacts drug bioavailability across an in vitro model of the blood-brain barrier (BBB) by CYP-multidrug transporter (multidrug resistance protein 1, MDR1) mechanisms. METHODS: Surgically resected brain specimens from patients with drug-resistant epilepsy, primary EPI-ECs, and control human brain microvascular endothelial cells (HBMECs) were used. Expression of GR, pregnane X receptor, CYP3A4, and MDR1 was analyzed pre- and post-GR silencing in EPI-ECs. Endothelial cells were co-cultured with astrocytes and seeded in an in vitro flow-based BBB model (DIV-BBB). Alternatively, the GR inhibitor mifepristone was added to the EPI-EC DIV-BBB. Integrity of the BBB was monitored by measuring transendothelial electrical resistance. Cell viability was assessed by glucose-lactate levels. Permeability of [3 H]sucrose and [14 C]phenytoin was quantified. CYP function was determined by measuring resorufin formation and oxcarbazepine (OXC) metabolism. RESULTS: Silencing and inhibition of GR in EPI-ECs resulted in decreased pregnane X receptor, CYP3A4, and MDR1 expression. GR silencing or inhibition did not affect BBB properties in vitro, as transendothelial electrical resistance and Psucrose were unaltered, and glucose metabolism was maintained. GR EPI-EC silencing or inhibition led to (1) increased Pphenytoin BBB permeability as compared to control; (2) decreased CYP function, indirectly evaluated by resorufin formation; (3) improved OXC bioavailability with increased abluminal (brain-side) OXC levels as compared to control. SIGNIFICANCE: Our results suggest that modulating GR expression in EPI-ECs at the BBB modifies drug metabolism and penetration by a mechanism encompassing P450 and efflux transporters. The latter could be exploited for future drug design and to overcome pharmacoresistance.


Assuntos
Células Endoteliais/metabolismo , Epilepsia/patologia , RNA Interferente Pequeno/uso terapêutico , Receptores de Glucocorticoides/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Anticonvulsivantes/farmacocinética , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Biotransformação , Encéfalo/patologia , Células Cultivadas , Citocromo P-450 CYP3A/metabolismo , Células Endoteliais/efeitos dos fármacos , Humanos , Mifepristona/farmacocinética , Mifepristona/uso terapêutico , Modelos Biológicos , Oxazinas/farmacologia , Receptor 1 de Sinal de Orientação para Peroxissomos/metabolismo , Fenitoína/farmacocinética , RNA Interferente Pequeno/metabolismo , Receptores de Glucocorticoides/genética , Sacarose/farmacocinética
7.
Epilepsia ; 59(1): 123-134, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29125184

RESUMO

OBJECTIVE: Available evidence points to a role of cytochrome P450 (Cyp) drug biotransformation enzymes in central nervous system diseases, including epilepsy. Deviations in drug pharmacokinetic profiles may impact therapeutic outcomes. Here, we ask whether spontaneous recurrent seizure (SRS) activity is sufficient to modulate the expression of major Cyp enzymes in the liver and brain. METHODS: Unilateral intrahippocampal (IH) kainic acid (KA) injections were used to elicit nonconvulsive status epilepticus (SE), epileptogenesis, and SRS, as monitored by video-electroencephalography. Intraperitoneal (IP) KA injection was used to trigger generalized tonic-clonic SE. KA-injected mice and sham controls were sacrificed at 24-72 hours and 1 week post-SE (IH or IP KA), and during the chronic stage (SRS; 6 weeks post-IH KA). Liver and brain tissues were processed for histology, real-time quantitative polymerase chain reaction, Western blot, or microsomal enzymatic assay. Cyp2e1, Cyp3a13, glial fibrillary acidic protein (GFAP), IBA1, xenobiotic nuclear receptors nr1i2 (PXR), nr1i3 (CAR) and nr3c1 (glucocorticoid receptor [GR]) expression was examined. Serum samples were obtained to assay corticosterone levels, a GR activator. RESULTS: A significant increase of Cyp3a13 and Cyp2e1 transcript level and protein expression was found in the liver and hippocampi during SRS, as compared to control mice. In the ipsilateral hippocampus, Cyp2e1 and Cyp3a protein upregulation during SRS positively correlated to GFAP expression. GFAP+ , and not IBA1+ , cells colocalized with Cyp2e1 or Cyp3a expression. In the liver, a trend increase in Cyp3a microsomal activity was found during SRS as compared to control mice. The transcript levels of the Cyp upstream regulators GR, xenobiotic nr1i2, and nr1i3 receptors were unchanged at SRS. Corticosterone levels, a GR ligand, were increased in the blood post-SE. SIGNIFICANCE: SRS modifies Cyp expression in the liver and the hippocampus. Nuclear receptors or inflammatory pathways are candidate mechanisms of Cyp regulation during seizures.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Hipocampo/enzimologia , Fígado/enzimologia , Estado Epiléptico/enzimologia , Estado Epiléptico/patologia , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Receptor Constitutivo de Androstano , Corticosterona/sangue , Sistema Enzimático do Citocromo P-450/genética , Modelos Animais de Doenças , Vias de Administração de Medicamentos , Agonistas de Aminoácidos Excitatórios/toxicidade , Lateralidade Funcional/efeitos dos fármacos , Lateralidade Funcional/fisiologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Hipocampo/efeitos dos fármacos , Ácido Caínico/toxicidade , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Recidiva , Estatísticas não Paramétricas , Estado Epiléptico/sangue , Estado Epiléptico/induzido quimicamente , Fatores de Tempo
8.
Epilepsia ; 58(4): 576-585, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28199000

RESUMO

OBJECTIVE: Recent evidence suggests a metabolic contribution of cytochrome P450 enzymes (CYPs) to the drug-resistant phenotype in human epilepsy. However, the upstream molecular regulators of CYP in the epileptic brain remain understudied. We therefore investigated the expression and function of pregnane xenobiotic (PXR) and glucocorticoid (GR) nuclear receptors in endothelial cells established from post-epilepsy surgery brain samples. METHODS: PXR/GR localization was evaluated by immunohistochemistry in specimens from subjects who underwent temporal lobe resections to relieve drug-resistant seizures. We used primary cultures of endothelial cells obtained from epileptic brain tissues (EPI-ECs; n = 8), commercially available human brain microvascular endothelial cells (HBMECs; n = 8), and human hepatocytes (n = 3). PXR/GR messenger RNA (mRNA) levels in brain ECs was initially determined by complementary DNA (cDNA) microarrays. The expression of PXR/GR proteins was quantified by Western blot. PXR and GR silencing was performed in EPI-ECs (n = 4), and the impact on downstream CYP expression was determined. RESULTS: PXR/GR expression was detected by immunofluorescence in ECs and neurons in the human temporal lobe samples analyzed. Elevated mRNA and protein levels of PXR and GR were found in EPI-ECs versus control HBMECs. Hepatocytes, used as a positive control, displayed the highest levels of PXR/GR expression. We confirmed expression of PXR/GR in cytoplasmic-nuclear subcellular fractions, with a significant increase of PXR/GR in EPI-ECs versus controls. CYP3A4, CYP2C9, and CYP2E1 were overexpressed in EPI-ECs versus control, whereas CYP2D6 and CYP2C19 were downregulated or absent in EPI-ECs. GR silencing in EPI-ECs led to decreased CYP3A4, CYP2C9, and PXR expression. PXR silencing in EPI-ECs resulted in the specific downregulation of CYP3A4 expression. SIGNIFICANCE: Our results indicate increased PXR and GR in primary ECs derived from human epileptic brains. PXR or GR may be responsible for a local drug brain metabolism sustained by abnormal CYP regulation.


Assuntos
Encéfalo/patologia , Sistema Enzimático do Citocromo P-450/metabolismo , Epilepsia Resistente a Medicamentos/patologia , Células Endoteliais/metabolismo , Regulação Enzimológica da Expressão Gênica/fisiologia , Receptores de Glucocorticoides/metabolismo , Receptores de Esteroides/metabolismo , Análise de Variância , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Fosfopiruvato Hidratase/metabolismo , Receptor de Pregnano X , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Receptores de Glucocorticoides/genética , Receptores de Esteroides/genética , Frações Subcelulares/metabolismo
9.
Epilepsia ; 56(3): 439-49, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25656284

RESUMO

OBJECTIVE: Drug toxicity is a hurdle to drug development and to clinical translation of basic research. Antiepileptic drugs such as carbamazepine (CBZ) and selective serotonin reuptake inhibitors such as sertraline (SRT) are commonly co-prescribed to patients with epilepsy and comorbid depression. Because SRT may interfere with cytochrome P450 (CYP) enzyme activity and CYPs have been implicated in the conversion of CBZ to reactive cytotoxic metabolites, we investigated in vitro models to determine whether SRT affects the neurotoxic potential of CBZ and the mechanisms involved. METHODS: Human fetal brain-derived dopaminergic neurons, human brain microvascular endothelial cells (HBMECs), and embryonic kidney (HEK) cells were used to evaluate cytotoxicity of CBZ and SRT individually and in combination. Nitrite and glutathione (GSH) levels were measured with drug exposure. To validate the role of CYP3A4 in causing neurotoxicity, drug metabolism was compared to cell death in HEK CYP3A4 overexpressed and cells pretreated with the CYP3A4 inhibitor ketoconazole. RESULTS: In all cellular systems tested, exposure to CBZ (127 µM) or SRT (5 µM) alone caused negligible cytotoxicity. By contrast CBZ, tested at a much lower concentration (17 µM) in combination with SRT (5 µM), produced prominent cytotoxicity within 15 min exposure. In neurons and HBMECs, cytotoxicity was associated with increased nitrite levels, suggesting involvement of free radicals as a pathogenetic mechanism. Pretreatment of HBMECs with reduced GSH or with the GSH precursor N-acetyl-L-cysteine prevented cytotoxic response. In HEK cells, the cytotoxic response to the CBZ + SRT combination correlated with the rate of CBZ biotransformation and production of 2-hydroxy CBZ, further suggesting a causative role of reactive metabolites. In the same system, cytotoxicity was potentiated by overexpression of CYP3A4, and prevented by CYP3A4 inhibitor. SIGNIFICANCE: These results demonstrate an unexpected neurotoxic interaction between CBZ and SRT, apparently related to increased CYP3A4-mediated production of reactive CBZ metabolites. The potential clinical implications of these findings are discussed.


Assuntos
Anticonvulsivantes/toxicidade , Carbamazepina/toxicidade , Citocromo P-450 CYP3A/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Sertralina/farmacologia , Acetilcisteína/farmacologia , Adenilato Quinase/metabolismo , Encéfalo/citologia , Morte Celular/efeitos dos fármacos , Células Cultivadas , Citocromo P-450 CYP3A/genética , Inibidores do Citocromo P-450 CYP3A/farmacologia , Feto , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Cetoconazol/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Nitritos/metabolismo , Fatores de Tempo
10.
Heliyon ; 10(1): e23693, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38187285

RESUMO

A novel and distinct mutant with a phenotype, aeroplane wing (ae) is reported for the first time in the urban malaria vector Anopheles stephensi. The main aim of this study was to establish the mode of inheritance of the ae gene performing genetic crossings between the mutants and wild types. These mutants show extended open wings that are visible to naked eyes in both the sexes. Mutants were first noticed in a nutritionally stressed isofemale colony. Strategic genetic crosses revealed that the ae gene is a recessive, autosomal, and monogenic trait having full penetrance with uniform expression in its adult stage. Egg morphometric analysis confirmed that these mutants were intermediate variant. No significant differences were observed in the wing venation and size of ae mutants compared to their control parental lines. Further cytogenetic analysis on the ovarian polytene chromosome of ae mutant showed an inversion (3Li) on the 3L arm like its parental line. This ae mutant would be a prominent marker and could be useful to study the functions of related specific genes within its genome.

11.
J Biomol Struct Dyn ; : 1-15, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321949

RESUMO

Toxin-antitoxin (TA) modules, initially discovered on bacterial plasmids and subsequently identified within chromosomal contexts, hold a pivotal role in the realm of bacterial physiology. Among these, the pioneering TA system, ccd (Control of Cell Death), primarily localized on the F-plasmid, is known for its orchestration of plasmid replication with cellular division. Nonetheless, the precise functions of such systems within bacterial chromosomal settings remain a compelling subject that demands deeper investigation. To bridge this knowledge gap, our study focuses on exploring ccdABXn2, a chromosomally encoded TA module originating from the entomopathogenic bacterium Xenorhabdus nematophila. We meticulously delved into the system's genomic assignments, structural attributes, and functional interplay. Our findings uncovered intriguing patterns-CcdB toxin homologs exhibited higher conservation levels compared to their CcdA antitoxin counterparts. Moreover, we constructed secondary as well as tertiary models for both the CcdB toxin and CcdA antitoxin using threading techniques and subsequently validated their structural integrity. Our exploration extended to the identification of key interactions, including the peptide interaction with gyrase for the CcdB homolog and CcdB toxin interactions for the CcdA homolog, highlighting the intricate TA interaction network. Through docking and simulation analyses, we unequivocally demonstrated the inhibition of replication via binding the CcdB toxin to its target, DNA gyrase. These insights provide valuable knowledge about the metabolic and physiological roles of the chromosomally encoded ccdABXn2 TA module within the context of X. nematophila, significantly enhancing our comprehension of its functional significance within the intricate ecosystem of the bacterial host.Communicated by Ramaswamy H. Sarma.

12.
Neurobiol Dis ; 59: 206-19, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23880401

RESUMO

There are overwhelming data supporting the inflammatory origin of some epilepsies (e.g., Rasmussen's encephalitis and limbic encephalitis). Inflammatory epilepsies with an autoimmune component are characterized by autoantibodies against membrane-bound, intracellular or secreted proteins (e.g., voltage gated potassium channels). Comparably, little is known regarding autoantibodies targeting nuclear antigen. We tested the hypothesis that in addition to known epilepsy-related autoantigens, the human brain tissue and serum from patients with epilepsy contain autoantibodies recognizing nuclear targets. We also determined the specific nuclear proteins acting as autoantigen in patients with epilepsy. Brain tissue samples were obtained from patients undergoing brain resections to treat refractory seizures, from the brain with arteriovenous malformations or from post-mortem multiple sclerosis brain. Patients with epilepsy had no known history of autoimmune disease and were not diagnosed with autoimmune epilepsy. Tissue was processed for immunohistochemical staining. We also obtained subcellular fractions to extract intracellular IgGs. After separating nuclear antibody-antigen complexes, the purified autoantigen was analyzed by mass spectrometry. Western blots using autoantigen or total histones were probed to detect the presence of antinuclear antibodies in the serum of patients with epilepsy. Additionally, HEp-2 assays and antinuclear antibody ELISA were used to detect the staining pattern and specific presence of antinuclear antibodies in the serum of patients with epilepsy. Brain regions from patients with epilepsy characterized by blood-brain barrier disruption (visualized by extravasated albumin) contained extravasated IgGs. Intracellular antibodies were found in epilepsy (n=13/13) but not in multiple sclerosis brain (n=4/4). In the brain from patients with epilepsy, neurons displayed higher levels of nuclear IgGs compared to glia. IgG colocalized with extravasated albumin. All subcellular fractions from brain resections of patients with epilepsy contained extravasated IgGs (n=10/10), but epileptogenic cortex, where seizures originated from, displayed the highest levels of chromatin-bound IgGs. In the nuclear IgG pool, anti-histone autoantibodies were identified by two independent immunodetection methods. HEp-2 assay and ELISA confirmed the presence of anti-histone (n=5/8) and anti-chromatin antibodies in the serum from patients with epilepsy. We developed a multi-step approach to unmask autoantigens in the brain and sera of patients with epilepsy. This approach revealed antigen-bound antinuclear antibodies in neurons and free antinuclear IgGs in the serum of patients with epilepsy. Conditions with blood-brain barrier disruption but not seizures, were characterized by extravasated but not chromatin-bound IgGs. Our results show that the pool of intracellular IgG in the brain of patients with epilepsy consists of nucleus-specific autoantibodies targeting chromatin and histones. Seizures may be the trigger of neuronal uptake of antinuclear antibodies.


Assuntos
Anticorpos Antinucleares/metabolismo , Encéfalo/metabolismo , Cromatina/imunologia , Epilepsia , Histonas/imunologia , Neurônios/metabolismo , Adolescente , Adulto , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/patologia , Encéfalo/patologia , Criança , DNA/imunologia , Epilepsia/sangue , Epilepsia/imunologia , Epilepsia/patologia , Feminino , Humanos , Imunoglobulina G/metabolismo , Lactente , Masculino , Proteínas Associadas aos Microtúbulos/imunologia , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Neuroglia/metabolismo , Neuroglia/ultraestrutura , Neurônios/patologia , Neurônios/ultraestrutura , Frações Subcelulares/metabolismo , Adulto Jovem
13.
Epilepsia ; 54(9): 1562-70, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23865846

RESUMO

PURPOSE: Brain drug bioavailability is regulated by the blood-brain barrier (BBB). It was recently suggested that cytochrome P450 (CYP) enzymes could act in concert with multidrug transporter proteins to regulate drug penetration and distribution into the diseased brain. The possibility that phase II metabolic enzymes could be expressed in the epileptic brain has been not evaluated. Phase II enzymes are involved in the metabolism of common antiepileptic drugs (AEDs). METHODS: Phase II enzyme UGT1A4 brain expression was evaluated in temporal lobe resections from patients with epilepsy. UGT1A4 expression was determined by western blot and immunocytochemistry in primary cultures of human drug-resistant brain endothelial human brain epileptic endothelial cells (EPI-EC)s and commercially available control cells human brain microvascular endothelial cells (HBMECs). Lack of DNA condensation measured by 4',6-diamidino-2-phenylindole (DAPI) was used as a surrogate marker of cell viability and was correlated to UGT1A4 expression high performance liquid chromatography ultraviolet detection (HPLC-UV) was used to quantify lamotrigine metabolism by EPI-EC and HBMEC. The appearance of the specific lamotrigine metabolite, 2-n glucuronide (MET-1), was also evaluated. Lamotrigine and MET-1 levels were measured in selected surgical brain and matched blood samples. KEY FINDINGS: UGT1A4 expression was observed in BBB endothelial cells and neurons. Our quantification study revealed variable levels of UGT1A4 expression across the brain specimens analyzed. Neurons devoid of UGT1A4 expression displayed nuclear DAPI condensation, a sign of cellular distress. UGT1A4 overexpression in EPI-EC, as compared to HBMEC, was reflected by a proportional increase in lamotrigine metabolism. The lamotrigine metabolite, MET-1, was formed in vitro by EPI-EC and, to a lesser extent, by HBMEC. HPLC-UV measurements of brain and blood samples obtained from patients receiving lamotrigine prior to surgery revealed the presence of lamotrigine and its metabolites in the brain. SIGNIFICANCE: These initial results suggest the presence of a phase II enzyme in the epileptic brain. Further studies are required to fully describe the pattern of brain UGT1A4 expression in relation to clinical variables and drug resistance.


Assuntos
Anticonvulsivantes/uso terapêutico , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Resistência a Múltiplos Medicamentos , Epilepsia/metabolismo , Glucuronosiltransferase/metabolismo , Adulto , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/patologia , Células Endoteliais/metabolismo , Epilepsia/genética , Feminino , Humanos , Lamotrigina , Masculino , Pessoa de Meia-Idade , Neurônios/metabolismo , Triazinas/uso terapêutico
14.
Reprod Sci ; 30(11): 3359-3371, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37286756

RESUMO

Infertility affects 15% of global population. This study was designed to search out the most effective dose of chloroform fraction of hydro-ethanolic extract of Hygrophila auriculata seed to ameliorate cyproterone acetate (CPA)-treated male subfertility. The rats were made subfertile by CPA at the dose of 2.5 mg/100gm body weight for 45 days. The male subfertility represented by low sperm concentration, less motile, less viable, and less hypo osmotic tail swelled spermatozoa in CPA-treated group. Serum LH, FSH, and testosterone levels were significantly decreased in CPA-treated group in respect to control. Androgenic key enzyme Δ5,3ß-HSD, 17ß-HSD activities and gene expression pattern were also decreased significantly in respect to control. These antispermatogenic and antiandrogenic activities of CPA were significantly recovered after the treatment of Hygrophila auriculata at the dose of 2.5 mg, 5mg, and 10 mg/100gm body weight. CPA also generate oxidative free radical that indicated by altered catalase, superoxide dismutase, and peroxidase activities and protein expression pattern along with conjugated diene and thiobarbituric acid reactive substance levels in testis. Expression pattern of Bax and Bcl2 genes were deviated from control after CPA treatment. Significant diminution of body weight, organo-somatic indices, and SGOT, SGPT activities were observed in CPA-treated group. All these biomarkers significantly recovered towards control after the treatment of Hygrophila auriculata at different doses. More significant recovery was observed in 5 mg and 10 mg of chloroform fraction-treated group and 5 mg dose, i.e., the minimum therapeutic dose to recover the CPA-induced subfertility.


Assuntos
Acanthaceae , Infertilidade Masculina , Humanos , Masculino , Ratos , Animais , Acetato de Ciproterona/efeitos adversos , Acetato de Ciproterona/metabolismo , Testosterona , Clorofórmio/efeitos adversos , Clorofórmio/metabolismo , Sementes , Testículo/metabolismo , Infertilidade Masculina/metabolismo , Peso Corporal , Estresse Oxidativo
15.
bioRxiv ; 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38076947

RESUMO

Asthma is characterized by airway remodeling and hyperreactivity. Our earlier studies determined that the Nitric Oxide (NO)-soluble Guanylyl Cyclase (sGC)-cGMP pathway plays a significant role in human lung bronchodilation. However this bronchodilation is dysfunctional in asthma due to high NO levels which cause sGC to become heme-free and desensitized to its natural activator, NO. In order to determine how asthma impacts the various lung segments/lobes we mapped the inflammatory regions of lungs to determine whether such regions coincided with molecular signatures of sGC dysfunction. We demonstrate using models of mouse asthma (OVA, CFA/HDM) that the inflammed segments of the mouse asthma lungs can be tracked by upregulated expression of HO1 and these regions in-turn overlap with regions of heme-free sGC as evidenced by a decreased sGC-α1ß1 heterodimer and an increased response to heme-independent sGC activator, BAY 60-2770 relative to naïve uninflamed regions. We also find that NO generated from iNOS upregulation in the inflamed segments has a higher impact in developing heme-free sGC as increasing iNOS activity correlates linearly with elevated heme-independent sGC activation. This excess NO works by affecting the epithelial lung hemoglobin (Hb) to become heme-free in asthma thereby causing the Hb to lose its NO scavenging function and exposing the underlying smooth muscle sGC to excess NO, which in-turn becomes heme-free. Recognition of these specific lung segments enhance our understanding of the inflammed lungs in asthma with the ultimate aim to evaluate potential therapies and suggests that regional and not global inflammation impacts lung function in asthma.

16.
Parasit Vectors ; 16(1): 79, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36855157

RESUMO

BACKGROUND: Vector management programs rely on knowledge of the biology and genetic make-up of mosquitoes. Anopheles stephensi is a major invasive urban malaria vector, distributed throughout the Indian subcontinent and Middle East, and has recently been expanding its range in Africa. With the existence of three biological forms, distinctly identifiable based on the number of ridges on eggs and varying vectorial competence, An. stephensi is a perfect species for developing isofemale lines, which can be tested for insecticide susceptibility and vectorial competence of various biological forms. METHODS: We describe key steps involved in establishment and validation of isofemale lines. Isofemale colonies were further used for the characterization of insecticide susceptibility and differential vector competence. The results were statistically evaluated through descriptive and inferential statistics using Vassar Stat and Prism GraphPad software packages. RESULTS: Through a meticulous selection process, we overcame an initial inbreeding depression and found no significant morphometric differences in wings and egg size between the parental and respective isofemale lines in later generations. IndCh and IndInt strains showed variations in resistance to different insecticides belonging to all four major classes. We observed a significant change in vectorial competence between the respective isofemale and parental lines. CONCLUSIONS: Isofemale lines can be a valuable resource for characterizing and enhancing several genotypic and phenotypic traits. This is the first detailed report of the establishment of two isofemale lines of type and intermediate biological forms in Anopheles stephensi. The work encompasses characterization of fitness traits among two lines through a transgenerational study. Furthermore, isofemale colonies were established and used to characterize insecticide susceptibility and vector competence. The study provides valuable insights into differential susceptibility status of the parental and isofemale lines to different insecticides belonging to the same class. Corroborating an earlier hypothesis, we demonstrate the high vector competence of the type form relative to the intermediate form using homozygous lines. Using these lines, it is now possible to study host-parasite interactions and identify factors that might be responsible for altered susceptibility and increased vector competence in An. stephensi biological forms that would also pave the way for developing better vector management strategies.


Assuntos
Anopheles , Inseticidas , Malária , Animais , Anopheles/genética , Inseticidas/farmacologia , Malária/prevenção & controle , Mosquitos Vetores/genética , Fenótipo
17.
Neurobiol Dis ; 46(3): 692-700, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22426401

RESUMO

Drugs and their metabolites often produce undesirable effects. These may be due to a number of mechanisms, including biotransformation by P450 enzymes which are not exclusively expressed by hepatocytes but also by endothelial cells in brain from epileptics. The possibility thus exists that the potency of systemically administered central nervous system therapeutics can be modulated by a metabolic blood-brain barrier (BBB). Surgical brain specimens and blood samples (ex vivo) were obtained from drug-resistant epileptic subjects receiving the antiepileptic drug carbamazepine prior to temporal lobectomies. An in vitro blood-brain barrier model was then established using primary cell culture derived from the same brain specimens. The pattern of carbamazepine (CBZ) metabolism was evaluated in vitro and ex vivo using high performance liquid chromatography-mass spectroscopy. Accelerated mass spectroscopy was used to identify (14)C metabolites deriving from the parent (14)C-carbamazepine. Under our experimental conditions carbamazepine levels could not be detected in drug resistant epileptic brain ex situ; low levels of carbamazepine were detected in the brain side of the in vitro BBB established with endothelial cells derived from the same patients. Four carbamazepine-derived fractions were detected in brain samples in vitro and ex vivo. HPLC-accelerated mass spectroscopy confirmed that these signals derived from (14)C-carbamazepine administered as parental drug. Carbamazepine 10, 11 epoxide (CBZ-EPO) and 10, 11-dihydro-10, 11-dihydrooxy-carbamazepine (DiOH-CBZ) were also detected in the fractions analyzed. (14)C-enriched fractions were subsequently analyzed by mass spectrometry to reveal micromolar concentrations of quinolinic acid (QA). Remarkably, the disappearance of carbamazepine-epoxide (at a rate of 5% per hour) was comparable to the rate of quinolinic acid production (3% per hour). This suggested that quinolinic acid may be a result of carbamazepine metabolism. Quinolinic acid was not detected in the brain of patients who received antiepileptic drugs other than carbamazepine prior to surgery or in brain endothelial cultures obtained from a control patient. Our data suggest that a drug resistant BBB not only impedes drug access to the brain but may also allow the formation of neurotoxic metabolites.


Assuntos
Anticonvulsivantes/metabolismo , Química Encefálica , Carbamazepina/metabolismo , Convulsivantes/metabolismo , Epilepsia/induzido quimicamente , Ácido Quinolínico/farmacologia , Adulto , Biotransformação , Criança , Cromatografia Líquida de Alta Pressão , Resistência a Medicamentos , Células Endoteliais/efeitos dos fármacos , Epilepsia/metabolismo , Epilepsia do Lobo Temporal/tratamento farmacológico , Epilepsia do Lobo Temporal/metabolismo , Epilepsia do Lobo Temporal/cirurgia , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Modelos Neurológicos , Cultura Primária de Células , Ácido Quinolínico/química , Ácido Quinolínico/metabolismo , Reprodutibilidade dos Testes
18.
Epilepsia ; 53(11): 1877-86, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22905812

RESUMO

The blood-brain barrier (BBB) is located within a unique anatomic interface and has functional ramifications to most of the brain and blood cells. In the past, the BBB was considered a pharmacokinetic impediment to antiepileptic drug penetration into the brain; nowadays it is becoming increasingly evident that targeting of the damaged or dysfunctional BBB may represent a therapeutic approach to reduce seizure burden. Several studies have investigated the mechanisms linking the onset and sustainment of seizures to BBB dysfunction. These studies have shown that the BBB is at the crossroad of a multifactorial pathophysiologic process that involves changes in brain milieu, altered neuroglial physiology, development of brain inflammation, leukocyte-endothelial interactions, faulty angiogenesis, and hemodynamic changes leading to energy mismatch. A number of knowledge gaps, conflicting points of view, and discordance between clinical and experimental data currently characterize this field of neuroscience. As more pieces are added to this puzzle, it is apparent that each mechanism needs to be validated in an appropriate clinical context. We now offer a BBB-centric view of seizure disorders, linking several aspects of seizures and epilepsy physiopathology to BBB dysfunction. We have reviewed the therapeutic, antiseizure effect of drugs that promote BBB repair. We also present BBB neuroimaging as a tool to correlate BBB restoration to seizure mitigation. Add-on cerebrovascular drug could be of efficacy in reducing seizure burden when used in association with neuronal antiepileptic drugs.


Assuntos
Barreira Hematoencefálica/fisiopatologia , Epilepsia/sangue , Epilepsia/fisiopatologia , Animais , Anticonvulsivantes/metabolismo , Anticonvulsivantes/uso terapêutico , Transporte Biológico/fisiologia , Barreira Hematoencefálica/metabolismo , Epilepsia/tratamento farmacológico , Humanos
19.
Microb Cell Fact ; 11: 93, 2012 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-22759404

RESUMO

BACKGROUND: A useful goal for metabolic engineering would be to generate non-growing but metabolically active quiescent cells which would divert the metabolic fluxes towards product formation rather than growth. However, for products like recombinant proteins, which are intricately coupled to the growth process it is difficult to identify the genes that need to be knocked-out/knocked-in to get this desired phenotype. To circumvent this we adopted an inverse metabolic engineering strategy which would screen for the desired phenotype and thus help in the identification of genetic targets which need to be modified to get overproducers of recombinant protein. Such quiescent cells would obviate the need for high cell density cultures and increase the operational life span of bioprocesses. RESULTS: A novel strategy for generating a library, consisting of randomly down regulated metabolic pathways in E. coli was designed by cloning small genomic DNA fragments in expression vectors. Some of these DNA fragments got inserted in the reverse orientation thereby generating anti-sense RNA upon induction. These anti-sense fragments would hybridize to the sense mRNA of specific genes leading to gene 'silencing'. This library was first screened for slow growth phenotype and subsequently for enhanced over-expression ability. Using Green Fluorescent Protein (GFP) as a reporter protein on second plasmid, we were able to identify metabolic blocks which led to significant increase in expression levels. Thus down-regulating the ribB gene (3, 4 dihydroxy-2-butanone-4-phosphate synthase) led to a 7 fold increase in specific product yields while down regulating the gene kdpD (histidine kinase) led to 3.2 fold increase in specific yields. CONCLUSION: We have designed a high throughput screening approach which is a useful tool in the repertoire of reverse metabolic engineering strategies for the generation of improved hosts for recombinant protein expression.


Assuntos
Escherichia coli/metabolismo , Engenharia Metabólica , Proteínas Recombinantes/biossíntese , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , RNA Antissenso/genética , RNA Antissenso/metabolismo , RNA Mensageiro/metabolismo , Proteínas Recombinantes/genética
20.
Front Pharmacol ; 13: 983233, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36515436

RESUMO

Polytherapy with antiseizure medications (ASMs) is often used to control seizures in patients suffering from epilepsy, where about 30% of patients are pharmacoresistant. While drug combinations are intended to be beneficial, the consequence of CYP-dependent drug interactions on apoptotic protein levels and mitochondrial function in the epileptic brain remains unclear. We examined the interactions of ASMs given prior to surgery in surgically resected brain tissues and of three ASMs (lacosamide, LCM; oxcarbazepine, OXC; levetiracetam LEV) in isolated brain cells from patients with drug-resistant epilepsy (n = 23). We divided the patients into groups-those who took combinations of NON-CYP + CYP substrate ASMs, NON-CYP + CYP inducer ASMs, CYP substrate + CYP substrate or CYP substrate + CYP inducer ASMs-to study the 1) pro- and anti-apoptotic protein levels and other apoptotic signaling proteins and levels of reactive oxygen species (reduced glutathione and lipid peroxidation) in brain tissues; 2) cytotoxicity at blood-brain barrier epileptic endothelial cells (EPI-ECs) and subsequent changes in mitochondrial membrane potential in normal neuronal cells, following treatment with LCM + OXC (CYP substrate + CYP inducer) or LCM + LEV (CYP substrate + NON-CYP-substrate) after blood-brain barrier penetration, and 3) apoptotic and mitochondrial protein targets in the cells, pre-and post-CYP3A4 inhibition by ketoconazole and drug treatments. We found an increased BAX (pro-apoptotic)/Bcl-XL (anti-apoptotic) protein ratio in epileptic brain tissue after treatment with CYP substrate + CYP substrate or inducer compared to NON-CYP + CYP substrate or inducer, and subsequently decreased glutathione and elevated lipid peroxidation levels. Further, increased cytotoxicity and Mito-ID levels, indicative of compromised mitochondrial membrane potential, were observed after treatment of LCM + OXC in combination compared to LCM + LEV or these ASMs alone in EPI-ECs, which was attenuated by pre-treatment of CYP inhibitor, ketoconazole. A combination of two CYP-mediated ASMs on EPI-ECs resulted in elevated caspase-3 and cytochrome c with decreased SIRT3 levels and activity, which was rescued by CYP inhibition. Together, the study highlights for the first time that pro- and anti-apoptotic proteins levels are dependent on ASM combinations in epilepsy, modulated via a CYP-mediated mechanism that controls free radicals, cytotoxicity and mitochondrial activity. These findings lead to a better understanding of future drug selection choices offsetting pharmacodynamic CYP-mediated interactions.

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