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1.
Hum Mol Genet ; 31(7): 1022-1034, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-34559191

RESUMO

The purpose of our study is to determine DDQ (diethyl (3,4-dihydroxyphenethylamino) (quinolin-4-yl) methylphosphonate)-a newly discovered molecule that has been shown to protect against phosphorylated tau (p-tau) in Alzheimer's disease (AD) pathogenesis. We used a well-studied tau (P301L) transgenic mouse model to achieve our goal. We administered DDQ into 12-month-old Tau mice, at 20 mg/kg body weight intraperitoneally two times per week for 2 months. We also assessed DDQ levels in the blood, skeletal muscle and brain using biochemical and molecular techniques. We investigated the mRNA and protein levels of mitochondrial dynamics, biogenesis, synaptic, p-tau and longevity genes sirtuins in DDQ-treated tau mice using real-time quantitative PCR (q-RT-PCR), immunoblotting and immunofluorescence techniques. Our extensive pharmacodynamics investigations revealed that skeletal muscle had the greatest peak levels of DDQ, followed by serum and brain. Interestingly, DDQ-treated tau mice had higher levels of mitochondrial fusion, biogenesis, synaptic genes and sirtuins than DDQ-untreated tau mice. In addition, DDQ-treated tau mice had lower levels of mitochondrial fission and p-tau than untreated tau mice. The current findings, combined with our prior findings, firmly show that DDQ possesses anti-aging, anti-amyloid-beta and anti-p-tau properties, making it a promising molecule for reducing age-related, amyloid-beta and p-tau-induced synaptic and mitochondrial toxicities in AD.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Neurônios/metabolismo , Sinapses/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo
2.
Hum Mol Genet ; 31(3): 423-439, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34505123

RESUMO

The purpose of our study is to determine the protective effects of mitophagy enhancers against mutant APP and amyloid beta (Aß)-induced mitochondrial and synaptic toxicities in Alzheimer's disease (ad). Over two decades of research from our lab and others revealed that mitochondrial abnormalities are largely involved in the pathogenesis of both early-onset and late-onset ad. Emerging studies from our lab and others revealed that impaired clearance of dead or dying mitochondria is an early event in the disease process. Based on these changes, it has been proposed that mitophagy enhancers are potential therapeutic candidates to treat patients with ad. In the current study, we optimized doses of mitophagy enhancers urolithin A, actinonin, tomatidine, nicotinamide riboside in immortalized mouse primary hippocampal (HT22) neurons. We transfected HT22 cells with mutant APP cDNA and treated with mitophagy enhancers and assessed mRNA and protein levels of mitochondrial dynamics, biogenesis, mitophagy and synaptic genes, cell survival; assessed mitochondrial respiration in mAPP-HT22 cells treated and untreated with mitophagy enhancers. We also assessed mitochondrial morphology in mAPP-HT22 cells treated and untreated with mitophagy enhancers. Mutant APP-HT22 cells showed increased fission, decreased fusion, synaptic & mitophagy genes, reduced cell survival and defective mitochondrial respiration, and excessively fragmented and reduced length of mitochondria. However, these events were reversed in mitophagy-enhancers-treated mutant mAPP-HT22 cells. Cell survival was significantly increased, mRNA and protein levels of mitochondrial fusion, synaptic and mitophagy genes were increased, mitochondrial number is reduced, and mitochondrial length is increased, and mitochondrial fragmentation is reduced in mitophagy-enhancers-treated mutant APP-HT22 cells. Further, urolithin A showed strongest protective effects against mutant APP and Aß-induced mitochondrial and synaptic toxicities in ad. Based on these findings, we cautiously propose that mitophagy enhancers are promising therapeutic drugs to treat mitophagy in patients with ad.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Humanos , Camundongos , Mitocôndrias/metabolismo , Mitofagia/genética , RNA Mensageiro/metabolismo
3.
Hum Mol Genet ; 31(11): 1788-1805, 2022 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34919689

RESUMO

The purpose of our study is to understand the impact of a partial dynamin-related protein 1 (Drp1) on cognitive behavior, mitophagy, autophagy and mitochondrial and synaptic activities in transgenic Tau mice in Alzheimer's disease (AD). Our laboratory reported increased levels of amyloid-beta (Aß) and phosphorylated Tau (P-Tau) and reported that abnormal interactions between Aß and Drp1, P-Tau and Drp1 induced increased mitochondrial fragmentation and reduced fusion and synaptic activities in AD. These abnormal interactions result in the proliferation of dysfunctional mitochondria in AD neurons. Recent research on mitochondria revealed that fission protein Drp1 is largely implicated in mitochondrial dynamics in AD. To determine the impact of reduced Drp1 in AD, we recently crossed transgenic Tau mice with Drp1 heterozygote knockout (Drp1+/-) mice and generated double mutant (P301LDrp1+/-) mice. In the current study, we assessed the cognitive behavior, mRNA and protein levels of mitophagy, autophagy, mitochondrial biogenesis, dynamics and synaptic genes, mitochondrial morphology and mitochondrial function and dendritic spines in Tau mice relative to double mutant mice. When compared with Tau mice, double mutant mice did better on the Morris Maze (reduced latency to find hidden platform, increased swimming speed and time spent on quadrant) and rotarod (stayed a longer period of time) tests. Both mRNA- and protein-level autophagy, mitophagy, mitochondrial biogenesis and synaptic proteins were increased in double mutant mice compared with Tau (P301L) mice. Dendritic spines were significantly increased; mitochondrial number was reduced and length was increased in double mutant mice. Based on these observations, we conclude that reduced Drp1 is beneficial in a symptomatic-transgenic Tau (P301L) mice.


Assuntos
Doença de Alzheimer , Dinaminas , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Autofagia/genética , Cognição , Espinhas Dendríticas/metabolismo , Modelos Animais de Doenças , Dinaminas/genética , Dinaminas/metabolismo , Camundongos , Camundongos Transgênicos , Mitofagia/genética , RNA Mensageiro
4.
Infection ; 52(2): 429-437, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37697224

RESUMO

INTRODUCTION: Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections commonly cause hospital-acquired infections. The study aimed to compare the outcomes of CRKP infections between patients receiving ceftazidime avibactam +/- aztreonam and polymyxins in a hospital setting with a high prevalence of New Delhi Metallo Beta Lactamase production. METHODS: We conducted a retrospective cohort study from January 2020 to September 2022 in critically ill adult patients admitted to a non-COVID-19 medical intensive care unit with CRKP infection. The patients were followed up for a total of 30 days or death, whichever was later. RESULTS: Of a total of 106 patients included in the study, 65 patients received polymyxins and 41 patients received ceftazidime-avibactam +/- aztreonam. Higher 30-day mortality was noted in the polymyxin group (56.9% vs. 29.2%, P = 0.005). The mean time to event (mortality) in ceftazidime-avibactam +/- aztreonam was 23.9 + 1.5 days which was significantly higher compared to polymyxins (17.9 + 1.2 days, p = 0.006). On Cox regression analysis, after adjusting for the covariates, the hazard ratio for time to event with the use of polymyxin was 2.02 (95% CI: 1.03-3.9). CONCLUSION: Ceftazidime-avibactam + aztreonam is possibly associated with better clinical outcomes in patients infected with CRKP.


Assuntos
Compostos Azabicíclicos , Infecção Hospitalar , Infecções por Klebsiella , Adulto , Humanos , Ceftazidima/uso terapêutico , Aztreonam/uso terapêutico , Antibacterianos/uso terapêutico , Klebsiella pneumoniae , Polimixinas/uso terapêutico , Infecção Hospitalar/tratamento farmacológico , Estudos Retrospectivos , Combinação de Medicamentos , beta-Lactamases , Carbapenêmicos , Testes de Sensibilidade Microbiana , Infecções por Klebsiella/tratamento farmacológico
5.
Methods ; 218: 118-124, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37572768

RESUMO

The folding and stability of transmembrane proteins (TMPs) are governed by the insertion of secondary structural elements into the cell membrane followed by their assembly. Understanding the important features that dictate the stability of TMPs is important for elucidating their functions. In this work, we related sequence and structure-based parameters with free energy (ΔG0) of α-helical membrane proteins. Our results showed that the free energy transfer of hydrophobic peptides, relative contact order, total interaction energy, number of hydrogen bonds and lipid accessibility of transmembrane regions are important for stability. Further, we have developed multiple-regression models to predict the stability of α-helical membrane proteins using these features and our method can predict the stability with a correlation and mean absolute error (MAE) of 0.89 and 1.21 kcal/mol, respectively, on jack-knife test. The method was validated with a blind test set of three recently reported experimental ΔG0, which could predict the stability within an average MAE of 0.51 kcal/mol. Further, we developed a webserver for predicting the stability and it is freely available at (https://web.iitm.ac.in/bioinfo2/TMHS/). The importance of selected parameters and limitations are discussed.


Assuntos
Proteínas de Membrana , Peptídeos , Proteínas de Membrana/genética , Proteínas de Membrana/química , Peptídeos/química , Conformação Proteica em alfa-Hélice , Membrana Celular
6.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34518374

RESUMO

Most endangered species exist today in small populations, many of which are isolated. Evolution in such populations is largely governed by genetic drift. Empirical evidence for drift affecting striking phenotypes based on substantial genetic data are rare. Approximately 37% of tigers (Panthera tigris) in the Similipal Tiger Reserve (in eastern India) are pseudomelanistic, characterized by wide, merged stripes. Camera trap data across the tiger range revealed the presence of pseudomelanistic tigers only in Similipal. We investigated the genetic basis for pseudomelanism and examined the role of drift in driving this phenotype's frequency. Whole-genome data and pedigree-based association analyses from captive tigers revealed that pseudomelanism cosegregates with a conserved and functionally important coding alteration in Transmembrane Aminopeptidase Q (Taqpep), a gene responsible for similar traits in other felid species. Noninvasive sampling of tigers revealed a high frequency of the Taqpep p.H454Y mutation in Similipal (12 individuals, allele frequency = 0.58) and absence from all other tiger populations (395 individuals). Population genetic analyses confirmed few (minimal number) tigers in Similipal, and its genetic isolation, with poor geneflow. Pairwise FST (0.33) at the mutation site was high but not an outlier. Similipal tigers had low diversity at 81 single nucleotide polymorphisms (mean heterozygosity = 0.28, SD = 0.27). Simulations were consistent with founding events and drift as possible drivers for the observed stark difference of allele frequency. Our results highlight the role of stochastic processes in the evolution of rare phenotypes. We highlight an unusual evolutionary trajectory in a small and isolated population of an endangered species.


Assuntos
Evolução Biológica , Deriva Genética , Variação Genética , Genética Populacional , Melanose/genética , Fenótipo , Tigres/fisiologia , Sequência de Aminoácidos , Animais , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Genoma , Genótipo , Índia , Repetições de Microssatélites , Homologia de Sequência , Tigres/genética
7.
Ultrastruct Pathol ; 48(2): 128-136, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38115187

RESUMO

Radiation exposure is a major health concern due to bone involvement including mandible, causing deleterious effects on bone metabolism, and healing with an increasing risk of infection and osteoradionecrosis. This study aims to investigate the radiotherapy-induced microstructural changes in the human mandible by scanning electron microscopy (SEM). Mandibular cortical bone biopsies were obtained from control, irradiated, and patients with osteoradionecrosis (ORN). Bone samples were prepared for light microscopy and SEM. The SEM images were analyzed for the number of osteons, number of Haversian canal (HC), diameter of osteon (D.O), the diameter of HC (D.HC), osteonal wall thickness (O.W.Th), number of osteocytes, and number of osteocytic dendrites. The number of osteons, D.O, D.HC, O.W.Th, the number of osteocytes, and osteocytic dendrites were significantly decreased in both irradiated and ORN compared to controls (p < .05). The number of HCs decreased in irradiated and ORN bone compared to the control group. However, this was statistically not significant. The deleterious effect of radiation continues gradually altering the bone quality, structure, cellularity, and vascularity in the long term (>5 years mean radiation biopsy interval). The underlying microscopic damage in bone increases its susceptibility and contributes further to radiation-induced bone changes or even ORN.


Assuntos
Osteorradionecrose , Humanos , Microscopia Eletrônica de Varredura , Osteorradionecrose/etiologia , Osteorradionecrose/patologia , Osteócitos/patologia , Ósteon , Mandíbula/patologia
8.
Eur Arch Otorhinolaryngol ; 281(1): 509-513, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37816840

RESUMO

BACKGROUND: Mycetoma is a slowly progressive chronic granulomatous disease of the skin, subcutaneous tissue, and underlying or adjacent cartilage or bone. Most commonly involves the foot region. Other parts such as the knee, arm, leg, head, neck, thigh, perineum, chest, abdominal walls, facial bones, mandible, paranasal sinuses, eyelid, vulva, orbit, and scrotum are seldom affected. METHODS: This is a rare presentation of Eumycotic mycetoma involving the nasal septum. Surgical debridement is done under local anesthesia. Histopathological examination of debrided specimen guided in the diagnosis and treatment. RESULTS: Histopathological examination is the one that confirms the diagnosis and rules out the other granulomatous conditions and fungal rhinitis causing septal perforation. CONCLUSIONS: In an immunocompromised state, we know that mucormycosis and zygomycosis are known to cause aggressive complications like orbital invasion and palatal perforation by vascular route. However, other fungal infections also can lead to septal perforations whenever there is lessened resistance by the mucosal barrier due to trauma (nasal intubations).


Assuntos
Micetoma , Micoses , Seios Paranasais , Masculino , Feminino , Humanos , Micetoma/diagnóstico , Micetoma/microbiologia , Micetoma/patologia , Diálise Renal , Micoses/diagnóstico , Seios Paranasais/patologia , Septo Nasal/cirurgia , Septo Nasal/patologia
9.
ScientificWorldJournal ; 2024: 5117746, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495478

RESUMO

Sheet metal forming is one of the key processes for the automotive sector to be considered. Sheet metal formability is being tested as received, joining them with different welding/joining processes (i.e., tailored blanks) and making them as sandwich forms to reduce the total weight of the body. These sandwich formations of sheets are an advanced method by incorporating PVC/polymer sheets in between metal sheets with a suitable binder. The present work has investigated the formability of AA5052-PVC-AA5052 (Al-PVC-Al) sandwich sheets by considering the sheet rolling direction as a parameter. The mechanical properties of base metal and sandwich sheets were evaluated by conducting the uniaxial tensile tests. For forming behaviour of Al-PVC-Al sandwich sheets, in-plane plane stretching tests were performed on the universal tensile testing machine. From the results, it has been observed that 0-degree and 90-degree rolling direction of AA5052 sheets provided almost similar forming behaviour where the 45-degree rolling direction showed less formability. The limit strains (by which the forming limit curve has been developed and the safe and failure zones are separated) are 0.043, 0.038, and 0.043 of 0°, 45°, and 90°, respectively. Considering 0°-P-90°, 90°-P-90, 0°-P-45°, 0°-P-90°, and 45°-P-45° sandwich sheets with their corresponding limit strains of 0.060, 0.058,0.057, 0.052, and 0.050, a better formability is seen in 0°-P-90° sandwich, followed by 90°-P-90, 0°-P-45°, 0°-P-90°, and 45°-P-45°. The improvement in the formability is calculated as 28.33%, 25.86%, and 24.0% in comparison with the base metal in 0-degree, 90-degree, and 45-degree rolling directions and 0°-P-90°, 90°-P-90, and 45°-P-45° sandwich sheets.

10.
J Environ Manage ; 352: 120082, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38232595

RESUMO

New photoactive materials with uniform and well-defined morphologies were developed for efficient and sustainable photoelectrochemical (PEC) water splitting and hydrogen production. The investigation is focused on hydrothermal deposition of zinc oxide (ZnO) onto indium tin oxide (ITO) conductive surfaces and optimization of hydrothermal temperature for growing uniform sized 3D ZnO morphologies. Fine-tuning of hydrothermal temperature enhanced the scalability, efficiency, and performance of ZnO-decorated ITO electrodes used in PEC water splitting. Under UV light irradiation and using eco-friendly low-cost hydrothermal process in the presence of stable ZnO offered uniform 3D ZnO, which exhibited a high photocurrent of 0.6 mA/cm2 having stability up to 5 h under light-on and light-off conditions. The impact of hydrothermal temperature on the morphological properties of the deposited ZnO and its subsequent performance in PEC water splitting was investigated. The work contributes to advancement of scalable and efficient fabrication technique for developing energy converting photoactive materials.


Assuntos
Nanoestruturas , Óxido de Zinco , Óxido de Zinco/química , Água/química , Nanoestruturas/química , Compostos de Estanho/química
11.
AAPS PharmSciTech ; 25(5): 105, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724807

RESUMO

The formulation of microspheres involves a complex manufacturing process with multiple steps. Identifying the appropriate process parameters to achieve the desired quality attributes poses a significant challenge. This study aims to optimize the critical process parameters (CPPs) involved in the preparation of naltrexone microspheres using a Quality by Design (QbD) methodology. Additionally, the research aims to assess the drug release profiles of these microspheres under both in vivo and in vitro conditions. Critical process parameters (CPPs) and critical quality attributes (CQAs) were identified, and a Box-Behnken design was utilized to delineate the design space, ensuring alignment with the desired Quality Target Product Profile (QTPP). The investigated CPPs comprised polymer concentration, aqueous phase ratio to organic phase ratio, and quench volume. The microspheres were fabricated using the oil-in-water emulsion solvent extraction technique. Analysis revealed that increased polymer concentration was correlated with decreased particle size, reduced quench volume resulted in decreased burst release, and a heightened aqueous phase ratio to organic phase ratio improved drug entrapment. Upon analyzing the results, an optimal formulation was determined. In conclusion, the study conducted in vivo drug release testing on both the commercially available innovator product and the optimized test product utilizing an animal model. The integration of in vitro dissolution data with in vivo assessments presents a holistic understanding of drug release dynamics. The QbD approach-based optimization of CPPs furnishes informed guidance for the development of generic pharmaceutical formulations.


Assuntos
Química Farmacêutica , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Microesferas , Naltrexona , Tamanho da Partícula , Naltrexona/química , Naltrexona/administração & dosagem , Naltrexona/farmacocinética , Animais , Química Farmacêutica/métodos , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos/métodos , Polímeros/química , Emulsões/química , Composição de Medicamentos/métodos , Solubilidade , Solventes/química
12.
J Food Sci Technol ; 61(5): 1003-1012, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38487293

RESUMO

Traditional meat products like Haleem play a pivotal role in the culinary landscapes of Indian consumers, along with high economic value and business potential. Due to anticipated gains associated with adulterating 'Haleem' and constant evasion from regulatory oversight, the susceptibility to adulteration has substantially increased. Furthermore, no reports/surveillance regarding their labelling compliance has been reported. Hence, we conducted a 2-year surveillance using 100 samples collected from Hyderabad, India, using the Chipron™ DNA macroarray analysis technique. The method was validated for sensitivity (1%), specificity, and with proficiency test samples. Following this, the surveillance samples (beef, chicken, and mutton Haleem) were tested. The surveillance revealed an alarming adulteration of 46% of the samples, with different proportions of adulterant species. Adulteration of unconventional meat like camel meat was also found. These concerning results necessitate the requirement of stricter and constant regulatory surveillance to safeguard consumer trust and preserve the authenticity of traditional meat products. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05947-9.

13.
Hum Mol Genet ; 30(10): 847-864, 2021 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-33615359

RESUMO

The purpose of this study is to study the neuroprotective role of selective serotonin reuptake inhibitor (SSRI), citalopram, against Alzheimer's disease (AD). Multiple SSRIs, including citalopram, are reported to treat patients with depression, anxiety and AD. However, their protective cellular mechanisms have not been studied completely. In the current study, we investigated the protective role of citalopram against impaired mitochondrial dynamics, defective mitochondrial biogenesis, defective mitophagy and synaptic dysfunction in immortalized mouse primary hippocampal cells (HT22) expressing mutant APP (SWI/IND) mutations. Using quantitative RT-PCR, immunoblotting, biochemical methods and transmission electron microscopy methods, we assessed mutant full-length APP/C-terminal fragments and Aß levels and mRNA and protein levels of mitochondrial dynamics, biogenesis, mitophagy and synaptic genes in mAPP-HT22 cells and mAPP-HT22 cells treated with citalopram. Increased levels of mRNA levels of mitochondrial fission genes, decreased levels of fusion biogenesis, autophagy, mitophagy and synaptic genes were found in mAPP-HT22 cells relative to WT-HT22 cells. However, mAPP-HT22 cells treated with citalopram compared to mAPP-HT22 cells revealed reduced levels of the mitochondrial fission genes, increased fusion, biogenesis, autophagy, mitophagy and synaptic genes. Our protein data agree with mRNA levels. Transmission electron microscopy revealed significantly increased mitochondrial numbers and reduced mitochondrial length in mAPP-HT22 cells; these were reversed in citalopram-treated mAPP-HT22 cells. Cell survival rates were increased in citalopram-treated mAPP-HT22 relative to citalopram-untreated mAPP-HT22. Further, mAPP and C-terminal fragments werealso reduced in citalopram-treated cells. These findings suggest that citalopram reduces mutant APP and Aß and mitochondrial toxicities and may have a protective role of mutant APP and Aß-induced injuries in patients with depression, anxiety and AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Precursor de Proteína beta-Amiloide/genética , Citalopram/farmacologia , Dinâmica Mitocondrial/efeitos dos fármacos , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/genética , Animais , Autofagia/efeitos dos fármacos , Autofagia/genética , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Dinâmica Mitocondrial/genética , Mitofagia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Biogênese de Organelas , Sinapses/efeitos dos fármacos , Sinapses/genética
14.
Hum Mol Genet ; 31(2): 244-261, 2021 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-34432046

RESUMO

The purpose of our study is to understand the protective effects of small molecule ligands for phosphorylated tau (p-tau) in Alzheimer's disease (AD) progression. Many reports show evidence that phosphorylated tau is reported to be an important contributor to the formation of paired helical filaments (PHFs) and neurofibrillary tangles (NFTs) in AD neurons. In AD, glycogen synthase kinase-3 beta (GSK3ß), cyclin-dependent kinase-5 and dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A), are the three important kinases responsible for tau hyperphosphorylation. Currently, there are no drugs and/or small molecules that reduce the toxicity of phosphorylated tau in AD. In the present study, we rationally selected and validated small molecule ligands that bind to the phosphorylated tau at SER23 (Ser 285) and TYR44 (Tyr310). We also assessed the molecular dynamics and validated molecular docking sites for the three best ligands. Based on the best docking scores -8.09, -7.9 and -7.8 kcal/mol, we found that ligand 1 binds to key hyperphosphorylation residues of phosphorylated tau that inhibit abnormal PHF-tau, DYRK1A and GKS3ß that reduce phosphorylated tau levels in AD. Using biochemical, molecular, immunoblotting, immunofluorescence and transmission electron microscopy analyses, we studied the ligand 1 inhibition as well as mitochondrial and synaptic protective effects in immortalized primary hippocampal neuronal (HT22) cells. We found interactions between NAT10-262501 (ligand 1) and phosphorylated tau at key phosphorylation sites and these ligand-based inhibitions decreased PHF-tau, DYRK1A and GSK3ß levels. We also found increased mitochondrial biogenesis, mitochondrial fusion and synaptic activities and reduced mitochondrial fission in ligand 1-treated mutant tau HT22 cells. Based on these results, we cautiously conclude that phosphorylated tau NAT10-262501 (ligand 1) reduces hyperphosphorylation of tau based GKS3ß and CDK5 kinase regulation in AD, and aids in the maintenance of neuronal structure, mitochondrial dynamics and biogenesis with a possible therapeutic drug target for AD.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Humanos , Ligantes , Simulação de Acoplamento Molecular , Emaranhados Neurofibrilares/metabolismo , Fosforilação , Proteínas tau/metabolismo
15.
Hum Mol Genet ; 30(9): 789-810, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33791799

RESUMO

In the current study, we investigated the protective role of citalopram against cognitive decline, impaired mitochondrial dynamics, defective mitochondrial biogenesis, defective autophagy, mitophagy and synaptic dysfunction in APP transgenic mouse model of Alzheimer's disease (ad). We treated 12-month-old wild-type (WT) and age-matched transgenic APP mice with citalopram for 2 months. Using Morris Water Maze and rotarod tests, quantitative RT-PCR, immunoblotting, biochemical methods and transmission electron microscopy methods, we assessed cognitive behavior, RNA and protein levels of mitochondrial dynamics, biogenesis, autophagy, mitophagy, synaptic, ad-related and neurogenesis genes in wild-type and APP mice treated and untreated with citalopram. Citalopram-treated APP mice relative to citalopram-untreated APP mice exhibited improved cognitive behavior. Increased levels of mRNA associated with mitochondrial fission and ad-related genes; decreased levels of fusion, biogenesis, autophagy, mitophagy, synaptic and neurogenesis genes were found in APP mice relative to WT mice. However, APP mice treated with citalopram compared to citalopram-untreated APP mice revealed reduced levels of the mitochondrial fission and ad-related genes and increased fusion, biogenesis, autophagy, mitophagy, synaptic and neurogenesis genes. Our protein data agree with the mRNA levels. Transmission electron microscopy revealed significantly increased mitochondrial numbers and reduced mitochondrial length in APP mice; these were reversed in citalopram-treated APP mice. Further, Golgi-cox staining analysis revealed reduced dendritic spines in APP mice relative to WT mice. However, citalopram-treated APP mice showed significantly increased dendritic spines, indicating that citalopram enhances spine density, synaptic activity and improved cognitive function in APP mice. These findings suggest that citalopram reduces cognitive decline, Aß levels and mitochondrial and synaptic toxicities and may have a strong protective role against mutant APP and Aß-induced injuries in patients with depression, anxiety and ad.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Autofagia/genética , Citalopram/farmacologia , Citalopram/uso terapêutico , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Transgênicos , Dinâmica Mitocondrial/genética , Mitofagia , Neurônios/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico
16.
Antimicrob Agents Chemother ; : e0050023, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37314343

RESUMO

With limited and often toxic treatment options, carbapenem-resistant Gram-negative infections are associated with significant mortality. Cefepime-zidebactam is a promising antibiotic option undergoing a phase 3 trial that has activity against diverse antibiotic-resistant mechanisms in Gram-negative pathogens due to its ß-lactam enhancer mechanism, mediating multiple PBP binding. We report a case of disseminated infection caused by a New Delhi metallo-ß-lactamase-producing, extensively drug-resistant Pseudomonas aeruginosa isolate in a patient with acute T-cell leukemia, successfully managed with cefepime-zidebactam as a salvage therapy.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Infecções por Pseudomonas , Adulto , Humanos , Pseudomonas aeruginosa/metabolismo , Infecções por Pseudomonas/tratamento farmacológico , Terapia de Salvação , Cefalosporinas/uso terapêutico , Antibacterianos/uso terapêutico , beta-Lactamases/genética , beta-Lactamases/metabolismo , Compostos Azabicíclicos/uso terapêutico , Testes de Sensibilidade Microbiana
17.
Am J Gastroenterol ; 118(10): 1855-1863, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37463435

RESUMO

INTRODUCTION: Device-assisted enteroscopy has revolutionized the management of small-bowel disorders (SBD). No study to date has compared both novel motorized spiral enteroscopy (NMSE) and single-balloon enteroscopy (SBE) as a randomized controlled trial. Hence, this study was planned to include patients having SBD with the primary aim to compare the total enteroscopy rate (TER). METHODS: This study was conducted at the Asian Institute of Gastroenterology (AIG Hospitals), Hyderabad, India, from September 20, 2022, to December 15, 2022. All consecutive patients, older than 18 years with suspected SBD, and planned for total enteroscopy were screened for inclusion. The primary outcome was to compare the TER, and secondary outcomes were to compare the technical success, time taken to reach the depth of maximal insertion, withdrawal time, total procedure time, diagnostic yield, therapeutic success, and adverse events (AE). RESULTS: Seventy-two patients of the 110 patients screened were randomized in either NMSE (n = 35) or SBE (n = 37) group. The most common indication for the procedures was obscure gastrointestinal bleed (48%), others being unexplained abdominal pain with indeterminate radiologic findings (32%) and chronic diarrhea (20%). In NMSE group, the TER was 71.4%, whereas in the SBE group, it was 10.8% ( P < 0.0001). The total procedure time (minutes) was much lesser with NMSE (58.17 ± 21.5 minutes) vs SBE (114.2 ± 33.5 minutes) ( P < 0.0001). The diagnostic yield of NMSE (80%) was comparatively higher than SBE (62.1%) ( P = 0.096). Minor AE (grade I) were observed in both the groups: NMSE 8.5% (3/35) and SBE 5.4% (2/37). DISCUSSION: This randomized controlled trial shows that with NMSE higher TER can be achieved in shorter duration with minimal AE, compared with SBE.

18.
Microb Pathog ; 180: 106127, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37119939

RESUMO

Eggplant is one of the important vegetable crops grown across the world, and its production is threatened by both biotic and abiotic stresses. Diseases caused by viruses are becoming major limiting factors for its successful cultivation. A survey for begomovirus-like symptoms in 72 eggplant fields located in six different Indian states revealed a prevalence of disease ranging from 5.2 to 40.2%, and the symptoms recorded were mosaic, mottling, petiole bending, yellowing, and upward curling, vein thickening, and enation of the leaves, and stunting of plants. The causal agent associated with these plants was transmitted from infected leaf samples to healthy eggplant seedlings via grafting and whiteflies (Bemisia tabaci). The presence of begomovirus was confirmed in 72 infected eggplant samples collected from the surveyed fields exhibiting leaf curl and mosaic disease by PCR using begomovirus specifc primers (DNA-A componet), which resulted in an expected amplicon of 1.2 kb. The partial genome sequence obtained from amplified 1.2 kb from all samples indicated that they are closely related begomovirus species, tomato leaf Karnataka virus (ToLCKV, two samples), tomato leaf curl Palampur virus (ToLCPalV, fifty eggplant samples), and chilli leaf curl virus (ChLCuV, twenty samples). Based on the partial genome sequence analysis, fourteen representative samples were selected for full viral genome amplification by the rolling circle DNA amplification (RCA) technique. Analyses of fourteen eggplant isolates genome sequences using the Sequence Demarcation Tool (SDT) indicated that one isolate had the maximum nucleotide (nt) identity with ToLCKV and eight isolates with ToLCPalV. Whereas, four isolates four isolates (BLC1-CH, BLC2-CH, BLC3-CH, BLC4-CH) are showing nucleotide identity of less than 91% with chilli infecting viruses begomoviruses with chilli infecting begomoviruses and as per the guidelines given by the ICTV study group for the classification of begomoviruses these isolates are considered as one novel begomovirus species, for which name, Eggplant leaf curl Chhattisgarh virus (EgLCuChV) is proposed. For DNA-B component, seven eggplant isolates had the highest nt identity with ToLCPalV infecting other crops. Further, DNA satellites sequence analysis indicated that four betasatellites identified shared maximum nucleotide identity with the tomato leaf curl betasatellite and five alphasatellites shared maximum nucleotide identity with the ageratum enation alphasatellite. Recombination and GC plot analyses indicated that the bulk of begomovirus genome and associated satellites presumably originated from of previously known mono and bipartite begomoviruses and DNA satellites. To the best of our knowledge, this is India's first report of ToLCKV and a noval virus, eggplant leaf curl Chhattisgarh virus associated with eggplant leaf curl disease.


Assuntos
Begomovirus , Solanum melongena , Filogeografia , Filogenia , DNA Viral/genética , Índia , Doenças das Plantas
19.
Mol Biol Rep ; 50(2): 1857-1869, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36513866

RESUMO

The goal of this review is to increase public knowledge of the etiopathogenesis of diabetic eye diseases (DEDs), such as diabetic retinopathy (DR) and ocular angiosarcoma (ASO), and the likelihood of blindness among elderly widows. A widow's life in North India, in general, is fraught with peril because of the economic and social isolation it brings, as well as the increased risk of death from heart disease, hypertension, diabetes, depression, and dementia. Neovascularization, neuroinflammation, and edema in the ocular tissue are hallmarks of the ASO, a rare form of malignant tumor. When diabetes, hypertension, and aging all contribute to increased oxidative stress, the DR can proceed to ASO. Microglia in the retina of the optic nerve head are responsible for causing inflammation, discomfort, and neurodegeneration. Those that come into contact with them will get blind as a result of this. Advanced glycation end products (AGE), vascular endothelial growth factor (VEGF), protein kinase C (PKC), poly-ADP-ribose polymerase (PARP), metalloproteinase9 (MMP9), nuclear factor kappaB (NFkB), program death ligand1 (PDL-1), factor VIII (FVIII), and von Willebrand factor (VWF) are potent agents for ocular neovascularisation (ONV), neuroinflammation and edema in the ocular tissue. AGE/VEGF, DAG/PKC, PARP/NFkB, RAS/VEGF, PDL-1/PD-1, VWF/FVIII/VEGF, and RAS/VEGF are all linked to the pathophysiology of DEDs. The interaction between ONV and ASO is mostly determined by the VWF/FVIII/VEGF and PDL-1/PD-1 axis. This study focused on retinoprotective medications that can pass the blood-retinal barrier and cure DEDs, as well as the factors that influence the etiology of neovascularization and neuroinflammation in the eye.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Idoso , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator de von Willebrand/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Doenças Neuroinflamatórias , Receptor de Morte Celular Programada 1 , Neovascularização Patológica/tratamento farmacológico , Fatores de Crescimento do Endotélio Vascular , Retinopatia Diabética/metabolismo , Diabetes Mellitus/tratamento farmacológico
20.
Mol Divers ; 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37266849

RESUMO

N-methyl-D-aspartate receptors (NMDARs) play essential roles in vital aspects of brain functions. NMDARs mediate clinical features of neurological diseases and thus, represent a potential therapeutic target for their treatments. Many findings implicated the GluN2B subunit of NMDARs in various neurological disorders including epilepsy, ischemic brain damage, and neurodegenerative disorders such as Parkinson's disease, Alzheimer's disease, Huntington's chorea, and amyotrophic lateral sclerosis. Although a large amount of information is growing consistently on the importance of GluN2B subunit, however, limited recent data is available on how subunit-selective ligands impact NMDAR functions, which blunts the ability to render the diagnosis or craft novel treatments tailored to patients. To bridge this gap, we have focused on and summarized recently reported GluN2B selective ligands as emerging subunit-selective antagonists and modulators of NMDAR. Herein, we have also presented an overview of the structure-function relationship for potential GluN2B/NMDAR ligands with their binding sites and connection to CNS functionalities. Understanding of design rules and roles of GluN2B selective compounds will provide the link to medicinal chemists and neuroscientists to explore novel neurotherapeutic strategies against dysfunctions of glutamatergic neurotransmission.

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