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1.
J Pept Sci ; 28(8): e3405, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35068012

RESUMO

The synthesis of the orbitide[1-8-NαC]-zanriorb A1, isolated from the medicinal plant Zanthoxylum riedelianum, was investigated by solution-phase macrocyclization of a linear peptide and on-resin solid-phase macrocyclization with an acylsulfonamide safety-catch linker. The solution-phase route produced a mixture of proline rotamers, and the main component was assigned as the trans, cis rotamer, identical to the natural product. The on-resin cyclization was less successful, producing mainly a linear peptide, and minor cyclic products as rotameric mixtures. Although the natural product was reported to be significantly cytotoxic against Jurkat leukemia T cells, our synthetic peptides were inactive, suggesting the presence of other rotamers or impurities in the naturally isolated material. Additional analogues of zanriorb A1 were synthesized in which proline and glycine residues were replaced with alanine. While these analogues were not cytotoxic, several of them inhibited the production of nitric oxide in lipopolysaccharide (LPS)-stimulated macrophages. The most active compound, cyclic[Ala5,6,8 ]-zanriorb A1 had an IC50 of 22 µM and was more potent compared with the standard NG-monomethyl-l-arginine acetate (L-NMMA) with an IC50 of 98 µM, indicating their strong anti-inflammatory potential.


Assuntos
Antineoplásicos , Produtos Biológicos , Alanina , Anti-Inflamatórios/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Ciclização , Peptídeos Cíclicos/química , Prolina/química
2.
J Pak Med Assoc ; 71(3): 912-915, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34057947

RESUMO

OBJECTIVE: To explore the burden of drug-resistant tuberculosis in Khyber Pakhtunkhwa, Pakistan. METHODS: The cross-sectional study was conducted from March 1, 2016, to February 28, 2017, at the Khyber Pakhtunkhwa Tuberculosis Reference Laboratory, Hayatabad Medical Complex, Peshawar, Pakistan, and comprised referred suspected tuberculosis patient samples. Drug Susceptibility testing on all Mycobacterium tuberculosis complex strains was performed and data was subjected to statistical analysis. RESULTS: Of the 8220 samples, 4230 (51.5%) were related to females and 3990 (48.5%) to males. Also, 1978 (24%) were related to patients aged 15-24 years. Of the total, 1351 (16.5%) samples were positive on culture. Drug susceptibility testing showed 525 (39%) samples to be resistant to at least one of the first- and second-line drugs. Among the culture-positive cases, 5 (0.4%) were extensively drug-resistant, 62 (4.6%) multi-drug resistant, 243 (18%) polyresistant, 215 (16%) monoresistant and 826 (61%) were pan-sensitive. CONCLUSIONS: Drug-resistant tuberculosis in newly-diagnosed tuberculosis patients was alarmingly high in Khyber Pakhtunkhwa region.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Estudos Transversais , Farmacorresistência Bacteriana , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Mutação , Paquistão/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
3.
J Sci Food Agric ; 99(5): 2455-2462, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30367475

RESUMO

BACKGROUND: Garcinia (Clusiaceae) species are traditionally used as flavoring agents in curries and to cure several human health complications. This study investigated 31 macro, micro, and trace elements in microwave-assisted digested samples of Garcinia cambogia fruit and its anti-obesity commercial products by inductively coupled plasma-optical emission spectroscopy (ICP-OES) and inductively coupled plasma-mass spectrometric (ICP-MS) techniques. The methods were also validated using the coefficient of determination (R2 ), limits of detection and quantification (LOD, LOQ), precision (CV%), analysis of certified reference materials, spiking recovery experiments, and participation in an accredited laboratory proficiency test organized by Food Analysis Performance Assessment Scheme (FAPAS). RESULTS: Quality assurance confirmed that the methods were efficient and in accordance with criteria set by the Association of Official Analytical Chemists (AOAC). In the elemental analysis, the analyzed macro, micro, and trace essential elements were present in appreciable concentrations, which could meet the human nutritional requirements. Traces of toxic elements were within safe limits. CONCLUSION: From the results of the current study, the fruit and its commercial products could be considered potential sources of mineral elements without posing any threats to consumers. © 2018 Society of Chemical Industry.


Assuntos
Fármacos Antiobesidade/química , Garcinia cambogia/química , Extratos Vegetais/química , Oligoelementos/química , Fármacos Antiobesidade/economia , Fármacos Antiobesidade/toxicidade , Frutas/química , Garcinia cambogia/toxicidade , Limite de Detecção , Espectrometria de Massas , Extratos Vegetais/economia , Extratos Vegetais/toxicidade , Oligoelementos/economia
4.
Bioorg Chem ; 54: 60-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24813683

RESUMO

Garcinia hombroniana (seashore mangosteen) in Malaysia is used to treat itching and as a protective medicine after child birth. This study was aimed to investigate the bioactive chemical constituents of the bark of G. hombroniana. Ethyl acetate and dichloromethane extracts of G. hombroniana yielded two new (1, 9) and thirteen known compounds which were characterized by the spectral techniques of NMR, UV, IR and EI/ESI-MS, and identified as; 2,3',4,5'-tetrahydroxy-6-methoxybenzophenone(1), 2,3',4,4'-tetrahydroxy-6-methoxybenzophenone (2), 2,3',4,6-tetrahydroxybenzophenone (3), 1,3,6,7-tetrahydroxyxanthone (4), 3,3',4',5,7-pentahydroxyflavone (5),3,3',5,5',7-pentahydroxyflavanone (6), 3,3',4',5,5',7-hexahydroxyflavone (7), 4',5,7-trihydroxyflavanone-7-rutinoside (8), 18(13→17)-abeo-3ß-acetoxy-9α,13ß-lanost-24E-en-26-oic acid (9), garcihombronane B (10), garcihombronane D (11), friedelan-3-one (12), lupeol (13), stigmasterol (14) and stigmasterol glucoside (15). In the in vitro cytotoxicity against MCF-7, DBTRG, U2OS and PC-3 cell lines, compounds 1 and 9 displayed good cytotoxic effects against DBTRG cancer cell lines. Compounds 1-8 were also found to possess significant antioxidant activities. Owing to these properties, this study can be further extended to explore more significant bioactive components of this plant.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Benzofenonas/farmacologia , Garcinia/química , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Benzofenonas/química , Benzofenonas/isolamento & purificação , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Radicais Livres/antagonistas & inibidores , Humanos , Células MCF-7 , Estrutura Molecular , Picratos/antagonistas & inibidores , Relação Estrutura-Atividade , Ácidos Sulfônicos/antagonistas & inibidores , Triterpenos/química , Triterpenos/isolamento & purificação
5.
Magn Reson Chem ; 52(7): 345-52, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24700704

RESUMO

The genus Garcinia is reported to possess antimicrobial, anti-inflammatory, anticancer, hepatoprotective and anti-HIV activities. Garcinia hombroniana in Malaysia is used to treat itching and as a protective medicine after child birth. This study was aimed to isolate the chemical constituents from the bark of G. hombroniana and explore their possible pharmacological potential. Ethyl acetate extract afforded one new (1) and six (2-7) known 3 → 8 rotameric biflavonoids. Their structures were elucidated by UV, IR and NMR (1D and 2D) spectroscopy together with electron ionization/ESI mass spectrometric techniques and were identified as (2R, 3S) volkensiflavone-7-O-rhamnopyranoside (1), volkensiflavone (2), 4″-O-methyl-volkensiflavone (3), volkensiflavone-7-O-glucopyranoside (4), morelloflavone (5), 3″-O-methyl-morelloflavone (6) and morelloflavone-7-O-glucopyranoside (7). The absolute configuration of compound 1 was assigned by circular dichroism spectroscopy as 2R, 3S. The coexistence of conformers of isolated biflavonoids in solution at 25 °C in different solvents was confirmed by variable temperature NMR studies. At room temperature (25 °C), compounds 1-7 exhibited duplicate NMR signals, while at elevated temperature (90 °C), a single set of signals was obtained. Compound 5 showed significant in vitro antioxidant activities against 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis-3-ethyl benzthiazoline-6-sulfonic acid radicals. The antibacterial studies showed that compounds 5 and 6 are the most active against Staphylococcus aureus, Bacillus subtilis and Escherichia coli. Compounds 3 and 6 also showed moderate antituberculosis activity against H38 Rv. Based on the research findings, G. hombroniana could be concluded as a rich source of flavanone-flavone (3 → 8) biflavonoids that exhibit rotameric behaviour at room temperature and display significant antioxidant and antibacterial activities.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Biflavonoides/isolamento & purificação , Biflavonoides/farmacologia , Garcinia/química , Casca de Planta/química , Antibacterianos/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Biflavonoides/química , Espectroscopia de Ressonância Magnética/métodos , Fitoterapia/métodos , Componentes Aéreos da Planta/química , Extratos Vegetais/análise , Extratos Vegetais/química
6.
J Immunoassay Immunochem ; 35(2): 120-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24295176

RESUMO

To overcome and eliminate tuberculosis (TB), definitive, reliable, and rapid diagnosis is mandatory. Presently, the diagnostic potential of acute and latent stage TB specific antigens i.e., Rv3803c and Rv2626c was determined. Immunogenic recombinant genes of Rv3803c and Rv2626c antigens were cloned in bacterial expression vector pET23b and expressed product was purified. The homogeneity and structural integrity was confirmed by Western blot analysis. Diagnostic potential of Rv3803c and Rv2626c antigens was analyzed using the sera of 140 active TB patients (AFB smear positive) by indirect ELISA. Ten patients of leprosy and 94 healthy individuals were taken as disease and normal control respectively. The data was analyzed using R statistical package. The sensitivity and specificity of Rv3803c in active TB patients was of 69.3% and 76.4% respectively with an area under ROC curve of 0.77, whereas sensitivity and specificity of Rv2626c 77.1% and 85.1%, respectively. The area under ROC curve of Rv2626c was 0.89 which was significantly higher than Rv3803c (p < 0.0001). Recombinant antigens Rv3803c and Rv2626c have potential to be used as diagnostic markers for TB and need to evaluate with other antigens for differential diagnosis of TB.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/análise , Galactosiltransferases/análise , Tuberculose/diagnóstico , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/sangue , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Ensaio de Imunoadsorção Enzimática , Galactosiltransferases/genética , Galactosiltransferases/imunologia , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/imunologia , Paquistão , Proteínas Recombinantes/análise , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Tuberculose/sangue , Tuberculose/imunologia
7.
Cureus ; 16(1): e52002, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38344549

RESUMO

BACKGROUND: Fetal hemoglobin (HbF) has been reported to be associated with disease severity and treatment response to HbF-inducing therapies like Hydroxyurea and thalidomide in patients suffering from transfusion-dependent beta-thalassemia (TDT). However, the role of hemoglobin A2 (HbA2) remains less clear in TDT, therefore this study aims to determine the impact of both HbF and HbA2 levels on disease severity and treatment response. METHODOLOGY: A prospective observational study was conducted at the Peshawar Institute of Medical Sciences and Fatimid Foundation Peshawar from May 2023 to October 2023. A total of 232 TDT-diagnosed patients were enrolled using a convenient sampling technique, whereas coinheritance of beta-thalassemia with other hemoglobinopathies was excluded. RESULT: This study reveals a significant impact of HbF on disease severity (p<0.05) but finds no substantial correlation (p>0.05) between HbA2 levels and disease severity. Additionally, HbF and HbA2 levels exhibit no association with treatment response categories in patients receiving HbF induction therapy, and various mutations do not significantly alter HbF and HbA2 levels or disease severity parameters in TDT patients. CONCLUSION: The study established a significant association between HbF and disease severity. However, regarding treatment response, neither HbF nor HbA2 levels impact response categories. Combinatorial treatment with hydroxyurea and thalidomide showed superior efficacy compared to monotherapy. A larger sample size and extended follow-up are recommended to further explore the impact of HbF, HbA2, and various mutations on disease severity and treatment response.

8.
Seizure ; 116: 74-80, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37574425

RESUMO

BACKGROUND: Adequate glucose supply is essential for brain function, therefore hypoglycemic states may lead to seizures. Since blood glucose supply for brain is buffered by liver glycogen, an impairment of liver glycogen synthesis by mutations in the liver glycogen synthase gene (GYS2) might result in a substantial neurological involvement. Here, we describe the phenotypes of affected siblings of two families harboring biallelic mutations in GYS2. METHODS: Two suspected families - a multiplex Pakistani family (family A) with three affected siblings and a family of Moroccan origin (family B) with a single affected child who presented with seizures and reduced fasting blood glucose levels were genetically characterized. Whole exome sequencing (WES) was performed on the index patients, followed by Sanger sequencing-based segregation analyses on all available members of both families. RESULTS: The variant prioritization of WES and later Sanger sequencing confirmed three mutations in the GYS2 gene (12p12.1) consistent with an autosomal recessive pattern of inheritance. A homozygous splice acceptor site variant (NM_021957.3, c. 1646 -2A>G) segregated in family A. Two novel compound heterozygous variants (NM_021957.3: c.343G>A; p.Val115Met and NM_021957.3: c.875A>T; p.Glu292Val) were detected in family B, suggesting glycogen storage disorder. A special diet designed to avoid hypoglycemia, in addition to change of the anti-seizure medication led to reduction in seizure frequency. CONCLUSIONS: This study suggests that the seizures in patients initially diagnosed with epilepsy might be directly caused, or influenced by hypoglycemia due to pathogenic variants in the GYS2 gene.


Assuntos
Glicemia , Hipoglicemia , Criança , Humanos , Sequenciamento do Exoma , Glicogênio Hepático , Mutação/genética
9.
Epilepsy Res ; 201: 107283, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38382230

RESUMO

Progressive myoclonic epilepsies (PMEs) are a group of neurodegenerative disorders, predominantly affecting adolescents and, characterized by generalized worsening myoclonus epilepsies, ataxia, cognitive deficits, and dementia. To date, several genes, having implications in diverse phenotypic expressions associated with PMEs, have been identified. Genetic diagnosis is available for most of the adolescence-onset myoclonic epilepsies. This study aimed to elucidate the genetic basis of PMEs in three multiplex Pakistani families exhibiting clinically variable phenotypes. Causative variant(s) in the studied families, and mode of segregation were identified by Whole Exome Sequencing (WES) of the probands, followed by bi-directional Sanger sequencing for final validation. We identified homozygous recessive CLN6 missense variant c.768 C>G (p.Asp256Glu) in Family 1, and c.889 C>A (p.Pro297Thr) variant in Family 2. While in Family 3, we found a homozygous variant (c.316dup) that caused a frameshift mutation, leading to a premature stop codon in the CLN6 protein, resulting in a truncated protein (p.Arg106ProfsTer26). Though CLN6 is previously identified to underlie late infantile and adolescent onset neuronal ceroid lipofuscinosis, this study supports and expands the phenotypic spectrum of CLN6 mutations and signifies diagnositc potential CLN6 variants for PMEs. Diverse pathological effects of variant c .768 C>G were observed in Family 1, with same genotypes, suggesting clinical heterogeneity and/or variable expressivity that might be the implication of pleiotropic effects of the gene in these cases.

10.
PLoS One ; 18(4): e0283589, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37053191

RESUMO

Non-coding RNAs (ncRNAs) can control the flux of genetic information; affect RNA stability and play crucial roles in mediating epigenetic modifications. A number of studies have highlighted the potential roles of both virus-encoded and host-encoded ncRNAs in viral infections, transmission and therapeutics. However, the role of an emerging type of non-coding transcript, circular RNA (circRNA) in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has not been fully elucidated so far. Moreover, the potential pathogenic role of circRNA-miRNA-mRNA regulatory axis has not been fully explored as yet. The current study aimed to holistically map the regulatory networks driven by SARS-CoV-2 related circRNAs, miRNAs and mRNAs to uncover plausible interactions and interplay amongst them in order to explore possible therapeutic options in SARS-CoV-2 infection. Patient datasets were analyzed systematically in a unified approach to explore circRNA, miRNA, and mRNA expression profiles. CircRNA-miRNA-mRNA network was constructed based on cytokine storm related circRNAs forming a total of 165 circRNA-miRNA-mRNA pairs. This study implies the potential regulatory role of the obtained circRNA-miRNA-mRNA network and proposes that two differentially expressed circRNAs hsa_circ_0080942 and hsa_circ_0080135 might serve as a potential theranostic agents for SARS-CoV-2 infection. Collectively, the results shed light on the functional role of circRNAs as ceRNAs to sponge miRNA and regulate mRNA expression during SARS-CoV-2 infection.


Assuntos
COVID-19 , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Medicina de Precisão , COVID-19/genética , SARS-CoV-2/genética
11.
Appl Biochem Biotechnol ; 194(12): 5907-5917, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35838887

RESUMO

Myeloproliferative neoplasms (MPNs) are blood cell disorders, characterized by overproduction of abnormal cells in bone marrow due to stem cell mutation. The proliferations of blood cell are controlled by many genes particularly MPL gene which encodes thrombopoietin receptor, a hematopoietic growth factor involved in the production and regulation of the platelets and multipotent hematopoietic progenitor cells. Acquired mutations including (W515L and W515K) in this gene have been observed in patients with primary myelofibrosis or essential thrombocythemia lacking JAK2 (V617F) mutations. MPL mutation detection is important for MPNs diagnosis, but due to low frequency of mutant allele burden (< 15%) may be missed by already available common assays such as Sanger sequencing. Furthermore, these techniques are costly, time-consuming, and less sensitive. In present study, we aimed to develop sensitive, less time-consuming, and cost-effective real-time PCR assay for the detection of MPL mutations that is based on TaqMan fluorescent probes. DNA was extracted from blood sample of 128 MPNs patients collected and further analysis was performed on TaqMan RT-PCR. Reference curve was obtained for amplified product of MPL gene containing mutated sequence. The predicted sensitivity level was at least 5% mutant allele burden by our developed assay that is much higher than sequencing output. Out of 128, 2 (1.56%) patients harbored W515L mutation and 1 (0.78%) harbored W515K mutation. It was concluded that TaqMan qRT-PCR assay is an efficient, sensitive, cost-effective, and less time-consuming method capable of detecting MPL mutation in MPNs patients. We suggested that this assay might be helpful in investigating mutant allele load in MPNs patients.


Assuntos
Transtornos Mieloproliferativos , Neoplasias , Humanos , Receptores de Trombopoetina/genética , Reação em Cadeia da Polimerase em Tempo Real , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/genética , Mutação
12.
Eur J Pharm Sci ; 168: 106045, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34666184

RESUMO

18ß-Glycyrrhetinic acid (18ß-GA) is known for several biological activities, and has been the focus of extensive research for the development of therapeutic agents. In the current study, 18ß-GA-peptide conjugates 2-11 were evaluated for their in vitro α-glucosidase inhibitory and antiglycation activities. Structure-activity relationship (SAR) established and molecular interactions of active bioconjugates with the enzyme's binding sites were predicted through molecular modeling approach. In tripeptide moiety of conjugates 2-11, peptide residue at position 1 was found to have a significant role on α-glucosidase inhibition. The most active 18ß-GA-peptide conjugates 5 (18ß-GA-Cys1-Tyr2-Gly3), and 8 (18ß-GA-Pro1-Tyr2-Gly3) exhibited several-fold potent α-glucosidase inhibition (IC50 values 20-28 µM), as compared to standard drug acarbose (IC50 = 875.8 ± 2.10 µM). Kinetic studies of potent compounds, 4-8 revealed that conjugate 5 exhibits competitive-type of inhibition, while conjugates 6-8 showed a non-competitive type of inhibition. The simulation studies also supported the kinetic results that conjugate 5 (18ß-GA-Cys1-Tyr2-Gly3) inhibits the α-glucosidase enzyme by blocking its substrate binding site. AGEs-induced NO• inhibitors play an important role in controlling the inflammation associated with diabetes mellitus. The peptide conjugates 2-11 were also evaluated in vitro for AGEs-induced NO• inhibition using RAW 264.7 macrophage cell line. Our data revealed that conjugates 7-10 were the more potent AGEs-induced NO• inhibitors, comparable to standards rutin, and PDTC. The peptide conjugate 5 (a competitive inhibitor of α-glucosidase) also exhibited a strong inhibitory activity against AGEs-induced NO• production. Furthermore, peptide conjugates 2-11 were found non-cytotoxic to mouse fibroblast NIH-3T3, and murine macrophages RAW 264.7 cell lines. In conclusion, our data demonstrates that besides possessing strong α-glucosidase inhibition, the newly synthesized peptide conjugates also alleviated the AGEs-induced NO• production in RAW macrophages. Dual inhibition of α-glucosidase enzyme, and AGEs-induced NO• production by 18ß-GA-peptide conjugates qualify them for further research in anti-diabetic drug discovery.


Assuntos
Ácido Glicirretínico , alfa-Glucosidases , Animais , Inibidores de Glicosídeo Hidrolases/farmacologia , Ácido Glicirretínico/análogos & derivados , Ácido Glicirretínico/farmacologia , Cinética , Camundongos , Simulação de Acoplamento Molecular , Peptídeos , Relação Estrutura-Atividade , alfa-Glucosidases/metabolismo
13.
Front Mol Neurosci ; 15: 1078441, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36727091

RESUMO

Altered autophagy is a hallmark of neurodegeneration but how autophagy is regulated in the brain and dysfunctional autophagy leads to neuronal death has remained cryptic. Being a key cellular waste-recycling and housekeeping system, autophagy is implicated in a range of brain disorders and altering autophagy flux could be an effective therapeutic strategy and has the potential for clinical applications down the road. Tight regulation of proteins and organelles in order to meet the needs of complex neuronal physiology suggests that there is distinct regulatory pattern of neuronal autophagy as compared to non-neuronal cells and nervous system might have its own separate regulator of autophagy. Evidence has shown that circRNAs participates in the biological processes of autophagosome assembly. The regulatory networks between circRNAs, autophagy, and neurodegeneration remains unknown and warrants further investigation. Understanding the interplay between autophagy, circRNAs and neurodegeneration requires a knowledge of the multiple steps and regulatory interactions involved in the autophagy pathway which might provide a valuable resource for the diagnosis and therapy of neurodegenerative diseases. In this review, we aimed to summarize the latest studies on the role of brain-protective mechanisms of autophagy associated circRNAs in neurodegenerative diseases (including Alzheimer's disease, Parkinson's disease, Huntington's disease, Spinal Muscular Atrophy, Amyotrophic Lateral Sclerosis, and Friedreich's ataxia) and how this knowledge can be leveraged for the development of novel therapeutics against them. Autophagy stimulation might be potential one-size-fits-all therapy for neurodegenerative disease as per considerable body of evidence, therefore future research on brain-protective mechanisms of autophagy associated circRNAs will illuminate an important feature of nervous system biology and will open the door to new approaches for treating neurodegenerative diseases.

14.
Chemosphere ; 272: 129794, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35534954

RESUMO

This study reports synthesis of Garcinia mangostana fruit pericarp (unwanted waste material) and α-mangostin mediated silver nanoparticles (AgNPs). These AgNPs were efficiently produced using 1:10 (extract and salt) ratio under stirring and heating, which was confirmed by surface plasmon resonance (SPR) band in UV-Visible spectroscopic analysis, and size of 73-91 nm determined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The synthesized AgNPs were used for Hg(II) detection in tap water, where the limits of detection and quantification were 2.6 µM and 8.9 µM, respectively. Furthermore, the subject AgNPs showed promising catalytic activity in the reduction of dyes and food colours including Congo red (CR), methylene blue (MB), malachite green (MG), methyl orange (MO), para-nitrophenol (PNP), rhodamine B (RdB), zarda yellow (ZY), deep green (DG), and bright red (BR). The synthesized AgNPs were also evaluated for their antioxidant, antimicrobial, and anticancer properties, where α-mangostin and its nanoparticles (Mang-AgNPs) exhibited promising IC50 values of 14.1 and 13.5 µg/mL, respectively against DU-145 cell line validated by in silico molecular docking study. This study is the first report highlighting the application of AgNPs of G. mangostana fruit pericarp extracts, and α-mangostin in Hg(II) detection, dyes degradation, and anticancer potential against DU-145. Finding of this study suggested the suitability of AgNPs as promising solid biosensor in Hg(II) metal detection, dyes reduction, and target in anticancer drug development.


Assuntos
Anti-Infecciosos , Garcinia mangostana , Mercúrio , Nanopartículas Metálicas , Antibacterianos/química , Anti-Infecciosos/química , Antioxidantes/química , Antioxidantes/farmacologia , Corantes/química , Garcinia mangostana/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Prata/química , Prata/farmacologia , Xantonas
15.
Int J Biol Macromol ; 147: 853-866, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31739066

RESUMO

Gums; composed of polysaccharides, carbohydrates, proteins, and minerals, are high molecular weight hydrophilic compounds with several biological applications. This study describes the nutritional and toxic elements content, chemical composition, synthesis of silver nanoparticles (G-AgNPs), and pharmacological and catalytic properties of Prunus armeniaca (apricot), Prunus domestica (plums), Prunus persica (peaches), Acacia modesta (phulai), Acacia arabica (kikar), and Salmalia malabarica (silk cotton tree) gums. The elemental contents were analyzed by inductively coupled plasma-optical emission spectroscopy (ICP-OES) and ICP-mass spectrometry (ICP-MS). NMR spectroscopy was used for the identification of class of compounds in the mixture, their functional groups were determined through FTIR techniques, and plasmon resonance and size of G-AgNPs through UV-Vis spectroscopic technique and transmission electron microscopy (TEM). From the results, nutritional elements were present at appreciable concentrations, whereas toxic elements showed content below the maximum permissible ranges. Using the elemental data, linear discriminant and principal component analyses classified the gums to 99.9% variability index. Furthermore, G-AgNPs exhibited significant antioxidant, antibacterial, and redox catalytic potential. Hence, the subject G-AgNPs could have promising nutritional, therapeutic and environmental remediation applications.


Assuntos
Antibacterianos , Antioxidantes , Nanopartículas Metálicas/química , Gomas Vegetais/química , Prata/química , Antibacterianos/síntese química , Antibacterianos/química , Antioxidantes/síntese química , Antioxidantes/química , Catálise
16.
Sci Rep ; 9(1): 14996, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628383

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis bacteria, is a leading infectious cause of mortality worldwide, including in Pakistan. Drug resistant M. tuberculosis is an emerging threat for TB control, making it important to detect the underlying genetic mutations, and thereby inform treatment decision making and prevent transmission. Whole genome sequencing has emerged as the new diagnostic to reliably predict drug resistance within a clinically relevant time frame, and its deployment will have the greatest impact on TB control in highly endemic regions. To evaluate the mutations leading to drug resistance and to assess for evidence of the transmission of resistant strains, 81 M. tuberculosis samples from Khyber Pakhtunkhwa province (North West Pakistan) were subjected to whole genome sequencing and standard drug susceptibility testing for eleven anti-TB drugs. We found the majority of M. tuberculosis isolates were the CAS/Delhi strain-type (lineage 3; n = 57; 70.4%) and multi-drug resistant (MDR; n = 62; 76.5%). The most frequent resistance mutations were observed in the katG and rpoB genes, conferring resistance to isoniazid and rifampicin respectively. Mutations were also observed in genes conferring resistance to other first and second-line drugs, including in pncA (pyrazinamide), embB (ethambutol), gyrA (fluoroquinolones), rrs (aminoglycosides), rpsL, rrs and giB (streptomycin) loci. Whilst the majority of mutations have been reported in global datasets, we describe unreported putative resistance markers in katG, ethA (ethionamide), gyrA and gyrB (fluoroquinolones), and pncA. Analysis of the mutations revealed that acquisition of rifampicin resistance often preceded isoniazid in our isolates. We also observed a high proportion (17.6%) of pre-MDR isolates with fluoroquinolone resistance markers, potentially due to unregulated anti-TB drug use. Our isolates were compared to previously sequenced strains from Pakistan in a combined phylogenetic tree analysis. The presence of lineage 2 was only observed in our isolates. Using a cut-off of less than ten genome-wide mutation differences between isolates, a transmission analysis revealed 18 M. tuberculosis isolates clustering within eight networks, thereby providing evidence of drug-resistant TB transmission in the Khyber Pakhtunkhwa province. Overall, we have demonstrated that drug-resistant TB isolates are circulating and transmitted in North West Pakistan. Further, we have shown the usefulness of whole genome sequencing as a diagnostic tool for characterizing M. tuberculosis isolates, which will assist future epidemiological studies and disease control activities in Pakistan.


Assuntos
Antituberculosos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Sequenciamento Completo do Genoma/métodos , Adolescente , Adulto , Sequência de Bases , DNA Bacteriano/genética , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Mycobacterium tuberculosis/isolamento & purificação , Paquistão/epidemiologia , Filogenia , Polimorfismo de Nucleotídeo Único , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/transmissão , Adulto Jovem
17.
Int J Mycobacteriol ; 6(1): 102-105, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28317814

RESUMO

BACKGROUND: Tuberculosis (TB) ranks as the second leading cause of deaths due to infectious diseases. Although global efforts have been made to control TB, still, this is a serious threat as Mycobacterium tuberculosis (MTB) produced resistance against both the first- and second-line drugs. The increasing incidence of multidrug-resistant, extremely drug resistant, and totally drug-resistant TB worldwide requires extra efforts to search for new anti-TB drugs. MATERIALS AND METHODS: The present study evaluated the antimycobacterial activities of Citrullus colocynthis, Calotropis procera, Ricinus communis, Capparis decidua, and Fagonia cretica plants' extracts against rifampicin-sensitive (H37Rv) and rifampicin-resistant (TMC331) strains of MTB. RESULTS: Out of 44 extracts, 19 extracts were found active against H37Rv sensitive strain. Highest activities were observed in chloroform extract of C. colocynthis (leaves) and n-hexane extract of R. communis (seeds) with minimum inhibitory concentration values of 2.5 mg/ml each. CONCLUSIONS: Results show antimycobacterial potential in some of the fractions of studied plants that may be utilized further for isolation of active compounds and as a possible cure against TB.


Assuntos
Antituberculosos/farmacologia , Descoberta de Drogas , Mycobacterium tuberculosis/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Calotropis/química , Clorofórmio , Citrullus/química , Farmacorresistência Bacteriana , Hexanos , Humanos , Testes de Sensibilidade Microbiana , Paquistão , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Ricinus/química , Rifampina/farmacologia , Sementes/química , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
18.
Afr J Tradit Complement Altern Med ; 14(2): 374-382, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28573253

RESUMO

BACKGROUND: Garcinia hombroniana, known as "manggis hutan" (jungle mangosteen) in Malaysia, is distributed in tropical Asia, Borneo, Thailand, Andaman, Nicobar Islands, Vietnam and India. In Malaysia, its ripened crimson sour fruit rind is used as a seasoning agent in curries and culinary dishes. Its roots and leaves decoction is used against skin infections and after child birth. This study aimed to evaluate in vivo hepatoprotective and in vitro cytotoxic activities of 20% methanolic ethyl acetate (MEA) G. hombroniana bark extract. MATERIALS AND METHODS: In hepatoprotective activity, liver damage was induced by treating rats with 1.0 mL carbon tetrachloride (CCl4)/kg and MEA extract was administered at a dose of 50, 250 and 500 mg/kg 24 h before intoxication with CCl4. Cytotoxicity study was performed on MCF-7 (human breast cancer), DBTRG (human glioblastoma), PC-3 (human prostate cancer) and U2OS (human osteosarcoma) cell lines. 1H, 13C-NMR (nuclear magnetic resonance), and IR (infrared) spectral analyses were also conducted for MEA extract. RESULTS: In hepatoprotective activity evaluation, MEA extract at a higher dose level of 500 mg/kg showed significant (p<0.05) potency. In cytotoxicity study, MEA extract was more toxic towards MCF-7 and DBTRG cell lines causing 78.7% and 64.3% cell death, respectively. MEA extract in 1H, 13C-NMR, and IR spectra exhibited bands, signals and J (coupling constant) values representing aromatic/phenolic constituents. CONCLUSIONS: From the results, it could be concluded that MEA extract has potency to inhibit hepatotoxicity and MCF-7 and DBTRG cancer cell lines which might be due to the phenolic compounds depicted from NMR and IR spectra.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Garcinia/química , Glioblastoma/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Antineoplásicos Fitogênicos/farmacologia , Tetracloreto de Carbono , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Fenóis/farmacologia , Fenóis/uso terapêutico , Casca de Planta , Extratos Vegetais/farmacologia , Ratos Sprague-Dawley
19.
Nat Prod Res ; 30(12): 1388-97, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26158779

RESUMO

The dichloromethane bark extract of Garcinia hombroniana yielded one new cycloartane triterpene; (22Z,24E)-3ß-hydroxycycloart-14,22,24-trien-26-oic acid (1) together with five known compounds: garcihombronane G (2), garcihombronane J (3), 3ß acetoxy-9α-hydroxy-17,14-friedolanostan-14,24-dien-26-oic acid (4), (22Z, 24E)-3ß, 9α-dihydroxy-17,14-friedolanostan-14,22,24-trien-26-oic acid (5) and 3ß, 23α-dihydroxy-17,14-friedolanostan-8,14,24-trien-26-oic acid (6). Their structures were established by the spectral techniques of NMR and ESI-MS. These compounds together with some previously isolated compounds; garcihombronane B (7), garcihombronane D (8) 2,3',4,5'-tetrahydroxy-6-methoxybenzophenone (9), volkensiflavone (10), 4''-O-methyll-volkensiflavone (11), volkensiflavone-7-O-glucopyranoside (12), volkensiflavone-7-O-rhamnopyranoside (13), Morelloflavone (14), 3''-O-methyl-morelloflavone (15) and morelloflavone-7-O-glucopyranoside (16) were evaluated for cholinesterase enzymes inhibitory activities using acetylcholinesterase and butyrylcholinesterase. In these activities, compounds 1-9 showed good dual inhibition on both the enzymes while compounds 10-16 did not reasonably contribute to both the cholinesterases inhibitory effects.


Assuntos
Inibidores da Colinesterase/farmacologia , Garcinia/química , Acetilcolinesterase/metabolismo , Biflavonoides/química , Biflavonoides/farmacologia , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Avaliação Pré-Clínica de Medicamentos/métodos , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Triterpenos/química , Triterpenos/farmacologia
20.
Nat Prod Res ; 29(1): 86-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25219673

RESUMO

Garcinia species are reported to possess antimicrobial, anti-inflammatory, anticancer, anti-HIV and anti-Alzheimer's activities. This study aimed to investigate the in vitro cholinesterase enzyme inhibitory activities of garcihombronane C (1), garcihombronane F (2), garcihombronane I (3), garcihombronane N (4), friedelin (5), clerosterol (6), spinasterol glucoside (7) and 3ß-hydroxy lup-12,20(29)-diene (8) isolated from Garcinia hombroniana, and to perform molecular docking simulation to get insight into the binding interactions of the ligands and enzymes. The cholinesterase inhibitory activities were evaluated using acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. In this study, compound 4 displayed the highest concentration-dependent inhibition of both AChE and BChE. Docking studies exhibited that compound 4 binds through hydrogen bonds to amino acid residues of AChE and BChE. The calculated docking and binding energies also supported the in vitro inhibitory profiles of IC50. In conclusion, garcihombronanes C, F, I and N (1-4) exhibited dual and moderate inhibitory activities against AChE and BChE.


Assuntos
Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Garcinia/química , Lanosterol/análogos & derivados , Plantas Medicinais/química , Acetilcolinesterase/efeitos dos fármacos , Butirilcolinesterase/efeitos dos fármacos , Inibidores da Colinesterase/química , Técnicas In Vitro , Concentração Inibidora 50 , Lanosterol/química , Lanosterol/isolamento & purificação , Lanosterol/farmacologia , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
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