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1.
J Fluoresc ; 34(1): 341-352, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37249676

RESUMO

Diversely substituted methoxy derivatives of arylpiperazinyl-alkyl benzothiazolone has been evaluated as specific probe for 5HT7. To determine the best methoxy derivative for 5HT7 receptor affinity, we synthesised a number of 2-benzothiazolone arylalkyl piperazine derivatives. In-vitro/vivo studies with C-2 substituted [11C]ABT showed 5HT7 specific binding. The radiochemical purity of [11C]ABT was found to be more than 99% with radiochemical stability persistence for more than 1.5 hr at 25 °C. The interaction of BSA and ABT has been analysed by photophysical studies for better understanding of properties such as adsortion, distribution, metabolism and elemination (ADME). The interaction between ABT and BSA was analyzed by using the UV-vis and fluorescence spectra. UV-vis spectra analyzed the changes in primary structure of BSA on its interaction with ABT. ABT showed quenched fluorescence emission intensity of tryptophan residues in BSA via static quenching mechanism. This study might help to understand how ABT binds to serum protein or subsequently to know the ADME of this drug candidate.


Assuntos
Serotonina , Soroalbumina Bovina , Soroalbumina Bovina/química , Serotonina/metabolismo , Espectrometria de Fluorescência , Dicroísmo Circular , Radiobiologia , Ligação Proteica , Termodinâmica
2.
Mol Psychiatry ; 27(10): 4218-4233, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35701597

RESUMO

Remarkable advances have been made in schizophrenia (SCZ) GWAS, but gleaning biological insight from these loci is challenging. Genetic influences on gene expression (e.g., eQTLs) are cell type-specific, but most studies that attempt to clarify GWAS loci's influence on gene expression have employed tissues with mixed cell compositions that can obscure cell-specific effects. Furthermore, enriched SCZ heritability in the fetal brain underscores the need to study the impact of SCZ risk loci in specific developing neurons. MGE-derived cortical interneurons (cINs) are consistently affected in SCZ brains and show enriched SCZ heritability in human fetal brains. We identified SCZ GWAS risk genes that are dysregulated in iPSC-derived homogeneous populations of developing SCZ cINs. These SCZ GWAS loci differential expression (DE) genes converge on the PKC pathway. Their disruption results in PKC hyperactivity in developing cINs, leading to arborization deficits. We show that the fine-mapped GWAS locus in the ATP2A2 gene of the PKC pathway harbors enhancer marks by ATACseq and ChIPseq, and regulates ATP2A2 expression. We also generated developing glutamatergic neurons (GNs), another population with enriched SCZ heritability, and confirmed their functionality after transplantation into the mouse brain. Then, we identified SCZ GWAS risk genes that are dysregulated in developing SCZ GNs. GN-specific SCZ GWAS loci DE genes converge on the ion transporter pathway, distinct from those for cINs. Disruption of the pathway gene CACNA1D resulted in deficits of Ca2+ currents in developing GNs, suggesting compromised neuronal function by GWAS loci pathway deficits during development. This study allows us to identify cell type-specific and developmental stage-specific mechanisms of SCZ risk gene function, and may aid in identifying mechanism-based novel therapeutic targets.


Assuntos
Esquizofrenia , Animais , Camundongos , Humanos , Esquizofrenia/genética , Esquizofrenia/metabolismo , Estudo de Associação Genômica Ampla/métodos , Interneurônios/metabolismo , Neurônios/metabolismo , Encéfalo/metabolismo , Predisposição Genética para Doença/genética
3.
Appl Microbiol Biotechnol ; 106(18): 5835-5862, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35989330

RESUMO

Several studies have demonstrated that when exposed to physical, chemical, and biological stresses in the environment, many bacteria (Gram-positive and Gram-negative) change their morphology from a normal cell to a filamentous shape. The formation of filamentous morphology is one of the survival strategies against environmental stress and protection against phagocytosis or protist predators. Numerous pathogenic bacteria have shown filamentous morphologies when examined in vivo or in vitro. During infection, certain pathogenic bacteria adopt a filamentous shape inside the cell to avoid phagocytosis by immune cells. Filamentous morphology has also been seen in biofilms formed on biotic or abiotic surfaces by certain bacteria. As a result, in addition to protecting against phagocytosis by immune cells or predators, the filamentous shape aids in biofilm adhesion or colonization to biotic or abiotic surfaces. Furthermore, these filamentous morphologies of bacterial pathogens lead to antimicrobial drug resistance. Clinically, filamentous morphology has become one of the most serious challenges in treating bacterial infection. The current review went into great detail about the various factors involved in the change of filamentous morphology and the underlying mechanisms. In addition, the review discussed a control strategy for suppressing filamentous morphology in order to combat bacterial infections. Understanding the mechanism underlying the filamentous morphology induced by various environmental conditions will aid in drug development and lessen the virulence of bacterial pathogens. KEY POINTS: • The bacterial filamentation morphology is one of the survival mechanisms against several environmental stress conditions and protection from phagocytosis by host cells and protist predators. • The filamentous morphologies in bacterial pathogens contribute to enhanced biofilm formation, which develops resistance properties against antimicrobial drugs. • Filamentous morphology has become one of the major hurdles in treating bacterial infection, hence controlling strategies employed for inhibiting the filamentation morphology from combating bacterial infections.


Assuntos
Bactérias , Infecções Bacterianas , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/prevenção & controle , Biofilmes , Humanos , Virulência
4.
Behav Pharmacol ; 30(8): 689-699, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31703031

RESUMO

Loss of midbrain dopaminergic neurons in Parkinson's disease not only induces motor impairments but also leads to the development of non-motor symptoms such as memory impairment, anxiety and depression. Dopaminergic axons directly innervate hippocampus and release dopamine in the local environment of hippocampus, and hence are directly involved in the modulation of hippocampal-dependent functions. Studies have explored the potential effect of dopamine on adult hippocampal neurogenesis. However, it is not well defined whether oxidative damage and inflammation could be associated with alteration in adult hippocampal neurogenesis. In the present study, we analyzed the effect of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine on adult hippocampal neurogenesis and how it is associated with inflammatory conditions in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease-like phenotypes. 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated mice exhibited significantly reduced dopaminergic neurons and dopamine content that resulted in impairment of motor functions. Interestingly, the formation of endogenous neuronal precursor cells and the number of neuroblasts in the hippocampus were significantly increased following 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine treatment. Net hippocampal neurogenesis was also reduced in the hippocampus after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine treatment. These effects in the hippocampus were associated with increased oxidative stress markers and a massive reactive gliosis. Taken together, our results suggest that degeneration of midbrain dopaminergic neurons directly affects the local hippocampal microenvironment by enhancing inflammatory influences. The 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced inflammatory reaction in the hippocampus may alter the endogenous regenerative capacity of the brain. Therefore, anti-inflammatory agents could be a potential therapy for the improvement of the endogenous regenerative capacity of the aging or neurodegenerative brain.


Assuntos
Neurogênese/efeitos dos fármacos , Neuroimunomodulação/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Modelos Animais de Doenças , Dopamina , Neurônios Dopaminérgicos/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurogênese/fisiologia , Neuroimunomodulação/fisiologia , Estresse Oxidativo/fisiologia , Doença de Parkinson , Substância Negra/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismo
5.
Neurochem Res ; 42(12): 3414-3430, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28836128

RESUMO

Purinoceptors are present in neurons, microglia and oligodendrocytes and regulate dopamine (DA) release, striatal-related function and striatal neuronal and DA cells damage. Therefore, purinoceptors may be involved in the pathology of Parkinson's disease (PD) and purinergic antagonism may show neuroprotective effect. The study investigated the role of the non-selective purinergic receptor antagonist pyridoxalphosphate-6-azophenyl-2', 4'-disulfonic acid (PPADS) and a selective purinergic receptor P2X7 receptor antagonist Brilliant Blue G (BBG) against 6-OHDA induced dopaminergic neurotoxicity in rats; while adenosine triphosphate (ATP) was used as a P2X receptor agonist. Behavioral parameters like spontaneous motor activity, narrow beam walk, footprint, bar catalepsy, grip strength and rotarod tests were performed to evaluate motor deficits in PD. Striatal DA contents were estimated as neurochemical measures of PD. Mitochondrial studies and oxidative status were assessed to investigate the mechanism of purinergic system antagonists. Involvement of purinergic receptors in apoptosis was assessed by expressing cytochrome-C, caspase-9 and caspase-3. Both the antagonists not only attenuated 6-OHDA induced motor deficits but also protected against 6-OHDA induced DA depletion in the striatum. Oxidative stress, mitochondrial integrity and dysfunction were attenuated by purinergic antagonists. Further, they attenuated mitochondrial-linked apoptosis as observed by a decrease in expression of cytochrome-C, caspase-9 and caspase-3. Therefore, purinoceptor antagonism shows neuroprotective effect in 6-OHDA induced dopamine toxicity through preservation of mitochondrial bioenergetics and anti-apoptotic activities.


Assuntos
Corpo Estriado/metabolismo , Dopamina/metabolismo , Mitocôndrias/efeitos dos fármacos , Oxidopamina/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Masculino , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson/metabolismo , Ratos
6.
Pulm Pharmacol Ther ; 36: 10-21, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26608704

RESUMO

Increased sympathetic nervous system (SNS) activity is associated with cardiovascular diseases but its role has not been completely explored in pulmonary hypertension (PH). Increased SNS activity is distinguished by elevated level of norepinephrine (NE) and activity of γ-Amino butyric acid Transminase (GABA-T) which degrades GABA, an inhibitory neurotransmitter within the central and peripheral nervous system. Therefore, we hypothesized that GABA-T may contribute in pathophysiology of PH by modulating level of GABA and NE. The effect of daily oral administration of GABA-T inhibitor, Vigabatrin (GVG, 50 and 75 mg/kg/day, 35 days) was studied following a single subcutaneous administration of monocrotaline (MCT, 60 mg/kg) in male SD rats. The pressure and hypertrophy of right ventricle (RV), oxidative stress, inflammation, pulmonary vascular remodelling were assessed after 35 days in MCT treated rats. The expression of GABA-T and HIF-1α was studied in lung tissue. The levels of plasma NE (by High performance liquid chromatography coupled with electrochemical detector; HPLC-ECD) and lung GABA (by liquid chromatography-mass spectrometry) were also estimated. GVG at both doses significantly attenuated increased in pressure (35.82 ± 4.80 mm Hg, p < 0.001; 28.37 ± 3.32 mm Hg, p < 0.001 respectively) and hypertrophy of RV, pulmonary vascular remodelling, oxidative stress and inflammation in lungs of MCT exposed rats. GVG also reduced the expression of GABA-T and HIF-1α in MCT treated rats. Increased NE level and decreased GABA level was also reversed by GVG in MCT exposed rats. GABA-T plays an important role in PH by modulating SNS activity and may be considered as a therapeutic target in PH.


Assuntos
4-Aminobutirato Transaminase/metabolismo , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/enzimologia , Monocrotalina , 4-Aminobutirato Transaminase/antagonistas & inibidores , Animais , Inibidores Enzimáticos/farmacologia , Hipertrofia Ventricular Direita/induzido quimicamente , Hipertrofia Ventricular Direita/fisiopatologia , Pulmão/metabolismo , Masculino , Norepinefrina/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/sangue , Pneumonia/fisiopatologia , Ratos , Ratos Sprague-Dawley , Análise de Sobrevida , Vigabatrina/farmacologia , Ácido gama-Aminobutírico/metabolismo
8.
Heliyon ; 10(5): e26724, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38434288

RESUMO

The present study describes the development of a potentiometric sensor for microbial monitoring in water based on catalase activity. The sensor comprises a MnO2-modified electrode that responds linearly to hydrogen peroxide (H2O2) from 0.16 M to 3.26 M. The electrode potential drops when the H2O2 solution is spiked with catalase or catalase-producing microorganisms that decompose H2O2. The sensor is responsive to different bacteria and their catalase activities. The electrochemical sensor exhibits a lower limit of detection (LOD) for Escherichia coli at 11 CFU/ml, Citrobacter youngae at 12 CFU/ml, and Pseudomonas aeruginosa at 23 CFU/ml. The sensor shows high sensitivity at 3.49, 3.02, and 4.24 mV/cm2dec for E. coli, C. youngae, and P. aeruginosa, respectively. The abiotic sensing electrode can be used multiple times without changing the response potential (up to 100 readings) with a shelf-life of over six months. The response time is a few seconds, with a total test time of 5 min. Additionally, the sensor effectively tested actual samples (drinking and grey water), which makes it a quick and reliable sensing tool. Therefore, the study offers a promising water monitoring tool with high sensitivity, stability, good detection limit, and minimum interference from other water contaminants.

9.
Immunol Cell Biol ; 91(6): 408-15, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23689305

RESUMO

Several studies have shown that interleukin (IL)-13 is induced in the esophageal biopsies of eosinophilic esophagitis (EoE) patients and promotes esophageal eosinophilia in mice, following an IL-13 challenge. However, the role of IL-13 has not been clearly investigated in allergen-induced EoE. Accordingly, we tested the hypothesis that IL-13 is required in allergen-induced EoE. Mice deficient in IL-13, STAT (signal transducer and activator of transcription)6 and both IL-4/IL-13 genes with their respective controls were challenged with Aspergillus extract, and IL-5 gene deficient with their control were challenged with recombinant IL-13, intranasally. The lung and esophageal eosinophils, mast cells and collagen accumulation were examined. Herein, we report that intranasal delivery of IL-13 promotes IL-5-dependent esophageal eosinophilia. However, allergen-induced EoE is not impaired in the IL-13 gene-deficient mice. In addition, wild-type and IL-13 gene-deficient mice demonstrated a comparable level of mast cells and collagen accumulation in the esophagus, following allergen-induced experimental EoE. Similarly, we found that esophageal eosinophilia in IL-4/IL-13 double gene-deficient and STAT6 gene-deficient mice were also not reduced following allergen-induced experimental EoE. In contrast, lung eosinophilia was significantly reduced in mice deficient in IL-13, both IL-4/IL-13 and STAT6 genes following allergen challenge. In conclusion, our data establish that allergen-induced EoE pathogenesis is independent of IL-13, whereas IL-13 is required for allergen-induced lung eosinophilia.


Assuntos
Aspergillus/metabolismo , Esofagite Eosinofílica/imunologia , Eosinófilos/imunologia , Esôfago/imunologia , Interleucina-13/metabolismo , Administração Intranasal , Alérgenos/imunologia , Animais , Antígenos de Fungos/imunologia , Aspergillus/imunologia , Movimento Celular/imunologia , Colágeno/metabolismo , Humanos , Interleucina-13/genética , Interleucina-13/imunologia , Interleucina-4/genética , Interleucina-5/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Fator de Transcrição STAT6/genética
10.
Artigo em Inglês | MEDLINE | ID: mdl-37610543

RESUMO

This study investigated the effect of co-culturing the photobiont and mycobiont in the microbial fuel cell (MFC) cathode on biomass production, lipid generation, and power output. Chlorella vulgaris provides oxygen and nutrients for the yeast Cystobasidium oligophagum JRC1, while the latter offers CO2 and quench oxygen for higher algal growth. The MFC with co-culture enhanced the lipid output of biomass by 28.33%, and the total yield and productivity were 1.47 ± 0.18 g/l and 0.123 g/l/day, respectively. Moreover, with co-culture, the open circuit voltage of 685 ± 11 mV was two times higher than algae alone. The specific growth rate (day-1) at the cathode was 0.367 ± 0.04 in co-culture and 0.288 ± 0.05 with C. vulgaris only. The power density of the system was 5.37 ± 0.21 mW/m2 with 75.88 ± 1.89% of COD removal. The co-culture thus proved beneficial at the MFC cathode in terms of total energy output as 11.5 ± 0.035 kWh/m3, which was 1.4-fold higher than algae alone.

11.
Curr Alzheimer Res ; 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37282567

RESUMO

AIMS: Caffeine possesses potent antioxidant, anti-inflammatory and anti-apoptotic activities against a variety of neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD). The goal of this study was to investigate the protective role of a psychoactive substance like caffeine on hippocampal neurogenesis and memory functions in streptozotocin (STZ)-induced neurodegeneration in rats. BACKGROUND: Caffeine is a natural CNS stimulant, belonging to the methylxanthine class, and is a widely consumed psychoactive substance. It is reported to abate the risk of various abnormalities that are cardiovascular system (CVS) related, cancer related, or due to metabolism dysregulation. Short-term caffeine exposure has been widely evaluated, but its chronic exposure is less explored and pursued. Several studies suggest a devastating role of caffeine in neurodegenerative disorders. However, the protective role of caffeine on neurodegeneration is still unclear. OBJECTIVE: Here, we examined the effects of chronic caffeine administration on hippocampal neurogenesis in intracerebroventricular STZ injection induced memory dysfunction in rats. The chronic effect of caffeine on proliferation and neuronal fate determination of hippocampal neurons was evaluated by co-labeling of neurons by thymidine analogue BrdU that labels new born cells, DCX (a marker for immature neurons) and NeuN that labels mature neurons. METHOD: STZ (1 mg/kg, 2 µl) was injected stereotaxically into the lateral ventricles (intracerebroventricular injection) once on day 1, followed by chronic treatment with caffeine (10 mg/kg, i.p) and donepezil (5 mg/kg, i.p.). Protective effect of caffeine on cognitive impairment and adult hippocampal neurogenesis was evaluated. RESULT: Our findings show decreased oxidative stress burden and amyloid burden following caffeine administration in STZ lesioned SD rats. Further, double immunolabeling with bromodeoxyuridine+/doublecortin+ (BrdU+/DCX+) and bromodeoxyuridine+/ neuronal nuclei+ (BrdU+/NeuN+) has indicated that caffeine improved neuronal stem cell proliferation and long term survival in STZ lesioned rats. CONCLUSION: Our findings support the neurogenic potential of caffeine in STZ induced neurodegeneration.

12.
ACS Chem Neurosci ; 14(12): 2271-2281, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37261380

RESUMO

The functional and developmental unit of neurogenesis is neural stem cells (NSCs). These NSCs have self-renewal capacity and produce new neurons throughout life in different neurogenic niche. Neurogenesis in adult brain is associated with synaptic plasticity, learning, and memory in dentate gyrus (DG) of hippocampus and olfactory bulb. Remarkably, weakened neurogenesis has been viewed before the onset of different pathological hallmarks of neurological disorders. In this review, we have provided evidence which implicates impaired neurogenesis as a culprit in age associated neurological disorders with greater emphasis on Alzheimer's disease (AD). Moreover, an insight about the molecular and cellular regulation linked with altered neurogenesis in young and aging brain has also been discussed. This review further summarizes the therapeutic strategies for targeting the manipulation of the neural stem cell pool and factors affecting the pool involved in AD.


Assuntos
Doença de Alzheimer , Células-Tronco Neurais , Adulto , Humanos , Doença de Alzheimer/patologia , Hipocampo/patologia , Células-Tronco Neurais/fisiologia , Neurogênese/fisiologia , Neurônios/patologia
13.
Eur J Pharmacol ; 946: 175623, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36871666

RESUMO

Activation of the renin-angiotensin system (RAS), by Angiotensin converting enzyme/Angiotensin II/Angiotensin receptor-1 (ACE/Ang II/AT1 R) axis elicits amyloid deposition and cognitive impairment. Furthermore, ACE2 induced release of Ang-(1-7) binds with the Mas receptor and autoinhibits ACE/Ang II/AT1 axis activation. Inhibition of ACE by perindopril has been reported to improve memory in preclinical settings. However, the functional significance and mechanism by which ACE2/Mas receptor regulate cognitive functions and amyloid pathology is not known. The present study is aimed to determine the role of ACE2/Ang-(1-7)/Mas receptor axis in STZ induced rat model of Alzheimer's disease (AD). We have used pharmacological, biochemical and behavioural approaches to identify the role of ACE2/Ang-(1-7)/Mas receptor axis activation on AD-like pathology in both in vitro and invivo models. STZ treatment enhances ROS formation, inflammation markers and NFκB/p65 levels which are associated with reduced ACE2/Mas receptor levels, acetylcholine activity and mitochondrial membrane potential in N2A cells. DIZE mediated ACE2/Ang-(1-7)/Mas receptor axis activation resulted in reduced ROS generation, astrogliosis, NFκB level and inflammatory molecules and improved mitochondrial functions along with Ca2+ influx in STZ treated N2A cells. Interestingly, DIZE induced activation of ACE2/Mas receptor significantly restored acetylcholine levels and reduced amyloid-beta and phospho-tau deposition in cortex and hippocampus that resulted in improved cognitive function in STZ induced rat model of AD-like phenotypes. Our data indicate that ACE2/Mas receptor activation is sufficient to prevented cognitive impairment and progression of amyloid pathology in STZ induced rat model of AD-like phenotypes. These findings suggest the potential role of ACE2/Ang-(1-7)/Mas axis in AD pathophysiology by regulating inflammation cognitive functions.


Assuntos
Doença de Alzheimer , Ratos , Animais , Doença de Alzheimer/patologia , Estreptozocina , Enzima de Conversão de Angiotensina 2/genética , Espécies Reativas de Oxigênio , Acetilcolina , Peptidil Dipeptidase A/metabolismo , Cognição , Inflamação/tratamento farmacológico , Fenótipo , Fragmentos de Peptídeos/farmacologia , Angiotensina I/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Angiotensina II/farmacologia
14.
Gels ; 9(11)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37998963

RESUMO

Chromium (Cr)-doped cobalt ferrite nanoparticles were synthesized using a sol-gel autocombustion method, with the chemical formula CoCrxFe2xO4. The value of x ranged from 0.00 to 0.5 in 0.1 increments. X-ray diffraction analysis confirmed the development of highly crystalline cubic spinel structures for all samples, with an average crystallite size of approximately 40 to 45 nm determined using the Scherrer equation. Pellets were prepared using a traditional ceramic method. The magnetic and magnetostrictive properties of the samples were tested using strain gauge and VSM (vibrating sample magnetometer) techniques. The results of the magnetic and magnetostrictive tests showed that the chromium-substituted cobalt ferrites exhibited higher strain derivative magnitudes than pure cobalt ferrite. These findings indicated that the introduction of chromium into the cobalt ferrite structure led to changes in the material's magnetic properties. These changes were attributed to anisotropic contributions, resulting from an increased presence of Co2+ ions at B-sites due to the chromium substitutions. In summary, this study concluded that introducing chromium into the cobalt ferrite structure caused alterations in the material's magnetic properties, which were explained by changes in the cationic arrangement within the crystal lattice. This study successfully explained these alterations using magnetization and coercivity data and the probable cationic dispersion.

15.
Neuron ; 111(6): 807-823.e7, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36626901

RESUMO

Previously, we demonstrated the efficacy of human pluripotent stem cell (hPSC)-derived GABAergic cortical interneuron (cIN) grafts in ameliorating seizures. However, a safe and reliable clinical translation requires a mechanistic understanding of graft function, as well as the assurance of long-term efficacy and safety. By employing hPSC-derived chemically matured migratory cINs in two models of epilepsy, we demonstrate lasting efficacy in treating seizures and comorbid deficits, as well as safety without uncontrolled growth. Host inhibition does not increase with increasing grafted cIN densities, assuring their safety without the risk of over-inhibition. Furthermore, their closed-loop optogenetic activation aborted seizure activity, revealing mechanisms of graft-mediated seizure control and allowing graft modulation for optimal translation. Monosynaptic tracing shows their extensive and specific synaptic connections with host neurons, resembling developmental connection specificity. These results offer confidence in stem cell-based therapy for epilepsy as a safe and reliable treatment for patients suffering from intractable epilepsy.


Assuntos
Epilepsia , Células-Tronco Pluripotentes , Humanos , Convulsões/terapia , Epilepsia/terapia , Interneurônios/fisiologia , Neurônios
16.
Am J Physiol Gastrointest Liver Physiol ; 302(7): G645-54, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22207581

RESUMO

Eosinophilic esophagitis (EoE) is a recently recognized inflammatory disorder driven by food hypersensitivity; however, the specific foods and mechanisms involved are unclear. In patients with EoE, we have found that hypersensitivities to corn and peanuts are the most common. Accordingly, we sensitized and exposed mice either intranasally or intragastrically with corn or peanut extract or saline. Esophageal eosinophilia, the genes of eosinophil-directed cytokines, and allergen-induced antibodies were examined in mice challenged with corn or peanut extract or saline. A high number of esophageal lamina propria eosinophils as well as eosinophilic microabscesses, intraepithelial eosinophils, extracellular eosinophilic granules, thickened and disrupted epithelial mucosa, and mast cell hyperplasia were observed in the esophagus of peanut or corn allergen-challenged mice. Mechanistic analysis indicated that para-esophageal lymph nodes might be critical in the trafficking of eosinophils to the esophagus and in EoE association to airway eosinophilia. Furthermore, experimentation with gene-targeted mice revealed that peanut allergen-induced EoE was dependent on eotaxin and invariant natural killer T (iNKT) cells, as CD1d and eotaxin-1/2 gene-deficient mice were protected from disease induction. Thus we provide evidence that para-esophageal lymph nodes are involved in food- or aeroallergen-induced eosinophilia and patchy EoE pathogenesis, likely a mechanism dependent on eotaxins and iNKT cells.


Assuntos
Esofagite Eosinofílica/imunologia , Hipersensibilidade Alimentar/imunologia , Linfonodos/fisiologia , Células T Matadoras Naturais/fisiologia , Animais , Antígenos CD1d/genética , Antígenos CD1d/imunologia , Arachis/imunologia , Aspergillus , Quimiocina CCL11/genética , Quimiocina CCL11/imunologia , Quimiocina CCL24/genética , Quimiocina CCL24/imunologia , Esofagite Eosinofílica/etiologia , Esofagite Eosinofílica/patologia , Esôfago/imunologia , Esôfago/patologia , Feminino , Hipersensibilidade Alimentar/complicações , Imunoglobulina E/metabolismo , Exposição por Inalação , Linfonodos/imunologia , Masculino , Mastócitos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/administração & dosagem , Extratos Vegetais/imunologia , Organismos Livres de Patógenos Específicos , Zea mays/imunologia
17.
ACS Chem Neurosci ; 13(10): 1491-1504, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35533351

RESUMO

Hypertension is reported to cause major brain disorders including Parkinson's disease (PD), apart from cardiovascular and chronic kidney disorders. Considering this, for the first time, we explored the effect of modulation of the ACE2/Ang (1-7)/MasR axis using diminazene aceturate (DIZE), an ACE2 activator, in 6-hydroxydopamine (6-OHDA) induced PD model. We found that DIZE treatment improved neuromuscular coordination and locomotor deficits in the 6-OHDA induced PD rat model. Further, the DIZE-mediated activation of ACE2 led to increased tyrosine hydroxylase (TH) and dopamine transporters (DAT) expression in the rat brain, indicating the protection of dopaminergic (DAergic) neurons from 6-OHDA induced neurotoxicity. Moreover, 6-OHDA induced activation of glial cells (astrocytes and microglia) and release of neuroinflammatory mediators were attenuated by DIZE treatment in both in vitro as well as in vivo models of PD. DIZE exerted its effect by activating ACE2 that produced Ang (1-7), a neuroprotective peptide. Ang (1-7) conferred its neuroprotective effect upon binding with the G-protein-coupled MAS receptor that led to the upregulation of cell survival proteins while downregulating apoptotic proteins. Importantly, these findings were further validated by using A-779, a MasR antagonist. The result showed that treatment with A-779 reversed the antioxidative and anti-inflammatory effects of DIZE by decreasing glial activation and neuroinflammatory markers. Although the role of ACE2 in PD pathology needs to be additionally confirmed using transgenic models in either ACE2 overexpressing or knockout mice, still, our study demonstrates that enhancing ACE2 activity could be a novel approach for ameliorating PD pathology.


Assuntos
Enzima de Conversão de Angiotensina 2 , Diminazena/análogos & derivados , Doença de Parkinson , Angiotensina I/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Diminazena/farmacologia , Camundongos , Modelos Teóricos , Oxidopamina/toxicidade , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/enzimologia , Fragmentos de Peptídeos/metabolismo , Peptidil Dipeptidase A/metabolismo , Proto-Oncogene Mas/metabolismo , Ratos , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
Food Chem ; 128(2): 450-7, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25212155

RESUMO

In the present study, storage proteins from five different wheat cultivars were extracted, fractionated and evaluated for their accumulation at different stages of development. SDS-PAGE analysis revealed that the accumulation of high molecular weight glutenin subunits was cultivar and stage dependent. However, low molecular weight glutenin subunits' accumulation was not altered significantly after 16days post anthesis in any of the cultivars. The rheological parameters (storage- and loss-modulus) of dough and gluten showed close association with either gliadins or glutenins. Peptidyl prolyl cis-trans isomerase (PPIase) activity, measured at different stages of grains development, showed variability with both the developmental stage and cultivar, and appeared to be primarily due to cyclophilins. Principal component analysis revealed the association of PPIase activity with either gliadin or total proteins, suggesting their significant role in the deposition of storage proteins in wheat.

19.
Brain Res ; 1754: 147261, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33422534

RESUMO

Antidepressants are well known to exert their role via upregulation of brain derived neurotrophic factor (BDNF). BDNF has been reported to exerts its neuroprotective effect in rodent and primate models as well as in patients of Alzheimer's disease (AD). The aim of our study was to evaluate the effect of protriptyline (PRT), a tricyclic antidepressant, in streptozotocin (STZ)- induced rat model of AD. Total 10 µl of STZ was injected into each ventricle (1 mg/kg). PRT (10 mg/kg, i.p.) treatment was started 3-day post STZ administration and continued till 21 days. We found that STZ treatment significantly increased pTau, Aß42 and BACE-1 expression, oxidative stress and neurodegeneration in hippocampus and cortex of adult rats. STZ induced impairment in spatial learning and retention memory was associated with increased NFκB and reduced CREB and BDNF expression in cortex and hippocampus. Interestingly, PRT treatment significantly reduced pTau, Aß42 and BACE-1 levels, neurodegeneration, oxidative stress and glial activation, contributing to the improved spatial learning and retention memory in STZ treated rats. Moreover, PRT treatment significantly improved p-ERK/ERK ratio and enhanced BDNF and CREB levels by reducing NFκB and GFAP expression in STZ treated rats. Our data suggest that impaired NFκB and CREB signaling potentially contribute in AD pathogenesis by elevating oxidative stress and neuroinflammation mediated neurodegeneration. Our study has established protriptyline as a multi target molecule in pre-clinical model of AD and further investigations on PRT like molecules could pave way for further development of effective new treatments in neurodegenerative disorders.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Protriptilina/farmacologia , Memória Espacial/efeitos dos fármacos , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/metabolismo , Fármacos Neuroprotetores/farmacologia , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Estreptozocina/farmacologia
20.
Brain Res Bull ; 172: 164-179, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33895271

RESUMO

Psychological and physical stress play a pivotal role in etiology of anxiety and depression. Chronic psychological and physical stress modify various physiological phenomena, as a consequence of which oxidative stress, decreased neurotransmitter level, elevated corticosterone level and altered NSC homeostasis is observed. However, the precise mechanism by which chronic stress induce anxious depression and modify internal milieu is still unknown. Herein, we show that exposure to CUS increase oxidative stress, microgliosis, astrogliosis while it reduces hippocampal NSC proliferation, neuronal differentiation and maturation in adult rats. CUS exposure in rats reduce dopamine and serotonin level in cortex and hippocampus, which result in increased anxiety and depression-like phenotypes. We also found elevated level of NF-κB and TNF-α while decreased anti-inflammatory cytokine IL-10 level, that led to increased expression of Bax and cleaved Caspase-3 whereas down regulation of antiapoptotic protein Bcl2. Additionally, CUS altered adult hippocampal neurogenesis, increased gliosis and neuronal apoptosis in cerebral cortex and hippocampus which might be associated with reduced AKT and increased ERK signaling, as seen in the rat brain tissue. Taken together, these results indicate that CUS induce oxidative stress and neuroinflammation which directly affects NSC dynamics, monoamines levels and behavioral functions in adult rats.


Assuntos
Ansiedade/metabolismo , Apoptose/fisiologia , Depressão/metabolismo , Hipocampo/metabolismo , Neurogênese/fisiologia , Estresse Psicológico/metabolismo , Animais , Comportamento Animal/fisiologia , Inflamação/metabolismo , Peroxidação de Lipídeos/fisiologia , Masculino , Estresse Oxidativo/fisiologia , Ratos , Ratos Sprague-Dawley
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