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1.
Homeopathy ; 113(2): 98-111, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37857331

RESUMO

BACKGROUND: The growing interest in identifying the mode of action of traditional medicines has strengthened its research. Syzygium jambolanum (Syzyg) is commonly prescribed in homeopathy and is a rich source of phytochemicals. OBJECTIVE: The present study aims to shed light on the anti-glycation molecular mechanism of Syzyg mother tincture (MT), 30c, and 200c on glycated human serum albumin (HSA) by multi-spectroscopic and microscopic approaches. METHODS: The phytochemicals and antioxidant potential of the Syzyg formulations were estimated by the high-performance liquid chromatography and spectroscopic technique, respectively. Glycation was initiated by incubating HSA with methylglyoxal, three Syzyg formulations, and the known inhibitor aminoguanidine in separate tubes at 37°C for 48 hours. The formation of glycation adducts was assessed by spectrofluorometer and affinity chromatography. The structural modifications were analyzed through circular dichroism, Fourier transform infrared spectroscopy, turbidity, 8-anilinonapthalene-1-sulfonic acid fluorescence, and nuclear magnetic resonance. Further, the formation of the aggregates was examined by thioflavin T, native-polyacrylamide gel electrophoresis, and transmission electron microscopy. Additionally, the functional modifications of glycated HSA were determined by esterase-like activity and antioxidant capacity. The binding analysis of Syzyg formulations with glycated HSA was evaluated by surface plasmon resonance (SPR). RESULTS: Syzyg formulations MT, 30c, and 200c contained gallic acid and ellagic acid as major phytochemicals, with concentrations of 16.02, 0.86, and 0.52 µg/mL, and 227.35, 1.35, and 0.84 µg/mL, respectively. Additionally, all three formulations had remarkable radical scavenging ability and could significantly inhibit glycation compared with aminoguanidine. Further, Syzyg formulations inhibited albumin's structural and functional modifications. SPR data showed that Syzyg formulations bind to glycated HSA with an equilibrium dissociation constant of 1.10 nM. CONCLUSION: Syzyg formulations inhibited the glycation process while maintaining the structural and functional integrity of HSA.


Assuntos
Guanidinas , Homeopatia , Syzygium , Humanos , Syzygium/metabolismo , Reação de Maillard , Antioxidantes/farmacologia , Albumina Sérica/química , Albumina Sérica/metabolismo
2.
Heliyon ; 9(11): e21604, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027753

RESUMO

Mobile phones have emerged as the predominant technology in developing countries, especially within agricultural enterprises. This research investigates the influence of mobile phone utilization on the empowerment of female entrepreneurs in rural farming communities. Data were gathered from 150 female agricultural entrepreneurs in the rural regions of Bangladesh. The empowerment of these women was assessed across five dimensions: economic, social, technological, psychological, and political. The findings indicate that the composite empowerment index was notably higher at 61.92% post-mobile phone adoption, in contrast to 37.47% prior to its use. This underscores the positive impact of mobile phone utilization on the empowerment of rural female farmers. The research highlighted significant enhancements in all five empowerment dimensions, with these augmentations being statistically meaningful. The most pronounced improvement was observed in economic empowerment, while political empowerment witnessed the least growth. Furthermore, the shifts were profoundly correlated with the other three dimensions: social, technological, and psychological. The evidence establishes a link between mobile phone adoption by rural female farmers and their subsequent empowerment, with empowerment metrics showing a steady rise from the low-usage to the high-usage categories. Consequently, the correlation is positive. The results advocate that mobile phone utilization assists rural female farmers in augmenting their empowerment. It is thus recommended that policymakers and developmental organizations prioritize mobile technology as a tool to empower rural women in Bangladesh. This can be realized by enhancing accessibility, confronting socio-cultural barriers, and fostering digital literacy.

3.
J Agric Food Res ; 14: 100752, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38169860

RESUMO

Traditional public extension worker-farmer cooperation in rice production demonstration is not working efficiently, therefore, private partnership-based demonstration has been attempted to introduce as its alternative very recently involving dealer-customer farmer. The study evaluated the private extension services rendered through dealer-customer farmer cooperation in Bangladesh. Thirty-three rice seed dealers and ninety-two customer farmers formed the samples for the study. Face-to-face interviews were employed as a quantitative method while focus group discussion was used as a qualitative method in the present study. Involving in the private rice production demonstration approach, customer farmers indicated high profit, greater involvement in decision-making, and improved marketing skills as the major advantages; while the dealers stressed the benefit received by the small farmers, improvement in their decision-making capacity and increased local rice production. However, the slow distribution of inputs during the production period was a weakness in the arrangement, which was mostly because of the dealers' lack of understanding of the customer farmers' needs. The private extension system being a new concept in the country may be observed over a period and gradually extended to the nooks and crannies of the country.

4.
Sci Total Environ ; 807(Pt 3): 151029, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34673078

RESUMO

Understanding the development mechanism of drought events, characterization of future drought metrics, and its impact on crop yield is crucial to ensure food security globally, and more importantly, in South Asia. Therefore, the present study assessed the changes in future projected drought metrics and evaluated the future risk of yield reduction under drought intensity. We characterized the magnitude, intensity, and duration of future drought by means of the SPEI drought index using CMIP6 (Coupled Model Inter-comparison Phase-6) climate models. The impact of future drought on crop yield was quantified from the ISI-MP (Inter-Sectoral Impact Model Inter-comparison Project) crop model by a proposed non-linear ensemble of Random Forest (RF) and Gradient Boosting Machine (GBM). Results suggested that high drought magnitude with a longer drought duration is projected in some regions of South Asia while high drought intensity comes with a shorter duration. It was also found that Afghanistan, Pakistan, and India will experience a longer drought duration in the future. Our proposed ensemble machine learning (EML) approach had high predictive skill with a minimum value of RMSE (0.358-0.390), MAE (0.222-0.299), and a maximum value of R2 (0.705-0.918) compared to the stand-alone methods of RF and GBM for yield loss risk projection. The drought-driven impact on crop yield demonstrates a high risk of yield loss under extreme drought events, which will encounter 54.15%, 29.30%, and 50.66% loss in the future for rice, wheat, and maize crops, respectively. Furthermore, drought and yield loss risk dynamics suggested a one unit decrease in SPEI value would lead to a 14.2%, 7.5%, and 10.9% decrease in yield for rice, wheat, and maize crops, respectively. This study will provide a notable direction for policy agencies to build resistance to crop production against the drought impact in the regions that are critical to climate change.


Assuntos
Modelos Climáticos , Produtos Agrícolas/crescimento & desenvolvimento , Secas , Afeganistão , Índia , Aprendizado de Máquina , Paquistão
5.
J Food Biochem ; : e13846, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34219237

RESUMO

Inhibition of non-enzymatic glycation processes is an essential aspect of treating type 2 diabetes and related complications. In this study, piperine's preventative, simultaneous and curative effect in glucose-induced albumin glycation was examined by analyzing the structural and functional markers of albumin. The protective and antioxidant influence of piperine on erythrocytes was assessed by examining cellular membrane modifications with antioxidant status. Albumin glycation was performed in three different experimental sets of 21 days at 37°C in dark conditions-using different piperine concentrations (250, 500, and 1,000 µM) and time of addition of glucose (30 mM)/piperine (1,000 µM) in a respective solution at 10th day. Piperine with glycated albumin leads to decreased fructosamine, carbonyl group, and protein-bound glucose. It had protected free amino groups, thiol group, and reduced beta-amyloid, protein aggregates formation. The presence of piperine with glycated albumin prevented erythrocytes hemolysis, membrane modifications, and maintained the antioxidant status. Piperine showed the antiglycation effects in a dose-dependent manner, additionally, its pre-treatment exhibited maximum attenuation by manifesting its primarily preventive role. PRACTICAL APPLICATIONS: Piperine is a natural alkaloid compound found in pepper, has been reported to possess anti-cancer, anti-microbial, and anti-inflammatory properties. The present study evaluated the antiglycation potential of piperine in albumin's glycation and it displayed preventive action, protected erythrocytes from oxidative damage induced by glycated albumin. We concluded that the daily intake of piperine can be adequate to prevent glycation-induced diabetic complications development in hyperglycemic conditions.

6.
Environ Sci Pollut Res Int ; 27(20): 25415-25433, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32347508

RESUMO

Land use and land cover changes (LULCC) significantly affect the climate at regional and global levels through different biogeophysical and biogeochemical processes. However, the effects of biogeophysical aspects of LULCC on climate have been often ignored, which may overestimate the biogeochemical effects on climate change. Thus, understanding the biogeophysical influence of land use changes on climate change in future potential scenarios is crucial. Therefore, it is necessary to identify the mechanism and land use change impacts on future climate under different scenarios through changes in underlying surface and surface energy balance. In order to fill this research gap, three simulations are performed by Weather Research Forecasting (WRF) model for the year 2010-2030 under Business-As-Usual (BAU) scenario, Rapid Economic Growth (REG) scenario, and Coordinated Environmental Sustainability (CES) scenario to evaluate the influence of future LULCC on temperature projections for the Punjab province in Pakistan. Results show that land use conversions under three scenarios induce overall climate cooling in the region. The decrease in annual average temperature in CES scenario (- 0.02 °C) is slightly greater than that in BAU and REG scenarios (- 0.01 °C). The responses of temperature to future LULCC vary in different months in all scenarios, with greater responses in warmer months, causing climate cooling. In each scenario, the response of temperature is found to be sensitive to different land transitions. The findings of the study can be a reference for policy makers, researchers, and development practitioners in their pursuit to understand the effects of land use change on climate.


Assuntos
Mudança Climática , Desenvolvimento Econômico , Previsões , Modelos Teóricos , Paquistão
7.
AMB Express ; 8(1): 116, 2018 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-30014253

RESUMO

The master regulator of thermal stress response, Hsf1, is also an essential determinant for viability and virulence in Candida albicans. Our recent studies highlighted that apart from ubiquitous roles of Hsf1 at higher temperatures, it also has myriad non-heat shock responsive roles essential under iron deprivation and drug defense. Here, we further explored its implications in the normal cellular functioning, by profiling its genome-wide occupancy using chromatin immuno-precipitation coupled to high-density tiling arrays under basal and iron deprived conditions. Hsf1 recruitment profiles revealed that it binds to promoters of 660 genes of varied functions, under both the conditions, however, elicited variability in intensity of binding. For instance, Hsf1 binding was observed on several genes of oxidative and osmotic stress response, cell wall integrity, iron homeostasis, mitochondrial, hyphal and multidrug transporters. Additionally, the present study divulged a novel motif under basal conditions comprising, -GTGn3GTGn3GTG- where, Hsf1 displays strong occupancy at significant number of sites on several promoters distinct from the heat induced motif. Hence, by binding to and regulating major chaperones, stress responsive genes and drug resistance regulators, Hsf1 is imperative in regulating various cellular machineries. The current study provides a framework for understanding novel aspects of how Hsf1 coordinates diverse cellular functions.

8.
Pharm Biol ; 55(1): 68-75, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27608964

RESUMO

CONTEXT: Protein glycation is the major contributing factor in the development of diabetic complications. The antiglycation potential of medicinal plants provides a promising opportunity as complementary interventions for complications. OBJECTIVE: To investigate the antiglycation potential of 19 medicinal plants extracts using albumin by estimating different indicators: (1) glycation (early and late), (2) albumin oxidation, and (3) amyloid aggregation. MATERIALS AND METHODS: The effect of aqueous plant extracts (1% w/v) on protein glycation was assessed by incubating albumin (10 mg/mL) with fructose (250 mM) for 4 days. Degree of protein glycation in the absence and presence of plant extracts was assessed by estimating fructosamine, advanced glycation end products (AGEs), carbonyls, free thiol group and ß-amyloid aggregation. RESULTS: Petroselinum crispum, Boerhavia diffusa, Terminalia chebula, Swertia chirayita and Glycyrrhiza glabra showed significant antiglycating activity. P. crispum and A. barbadensis inhibited the carbonyl stress and protected the thiol group from oxidative damage. There was significant correlation between protein thiols and amyloid inhibition (R = -.69, p < .001). CONCLUSION: P. crispum, B. diffusa and T. chebula had the most potent antiglycation activity. These plant exerted noticeable antiglycation activity at different glycation modifications of albumin. These findings are important for identifying plants with potential to combat diabetic complications.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Hipoglicemiantes/farmacologia , Nyctaginaceae/química , Petroselinum/química , Extratos Vegetais/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Soroalbumina Bovina/metabolismo , Terminalia/química , Frutosamina/metabolismo , Frutose/metabolismo , Glicosilação , Hipoglicemiantes/isolamento & purificação , Índia , Oxirredução , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Agregação Patológica de Proteínas , Carbonilação Proteica/efeitos dos fármacos , Compostos de Sulfidrila/metabolismo , Fatores de Tempo
9.
Biochim Biophys Acta Mol Cell Res ; 1864(2): 345-354, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27889440

RESUMO

Recently, we have reported that the conditional mutant of the heat shock factor-1 (HSF1) in Candida albicans displays enhanced susceptibility not only towards a plant alkaloid, berberine, but also to diverse antifungal drugs. The present study attempts to identify additional phenotypes highlighting the non-heat shock responsive roles of HSF1 that could be correlated with the enhanced drug susceptibility. We uncover an intricate relationship between cellular iron and HSF1 mediated drug susceptibility of C. albicans. Interestingly, at 30°C, the conditional deletion of HSF1 while presented no growth defect, exhibited low intracellular iron. Notably, exogenous supplementation of iron reversed growth defects of HSF1 mutant when grown at 37°C. We provide evidence that the HSF1 mutant presents interesting phenotypes at basal conditions and are implicated in enhanced drug susceptibilities, dysfunctional mitochondria, decreased resistance towards oxidative stress and compromised cell wall integrity, all of which could be fully reversed upon iron supplementation. The HSF1 mutant also displayed defective filamentation at basal conditions under various solid hypha inducing media. Further, chelation of iron of HSF1 mutant cells led to severe growth defects and apparently triggers an iron starvation signal in the cell thus, demonstrating that HSF1 is essential for C. albicans cells to tolerate the iron deprivation stress. Together, apart from the well-established roles of HSF1 in reciprocation of thermal stress, this study extends its role under basal conditions and provides molecular insights into the role of HSF1 in iron deprivation and drug defense of C. albicans.


Assuntos
Candida albicans/fisiologia , Farmacorresistência Fúngica , Proteínas de Choque Térmico/fisiologia , Ferro/metabolismo , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Parede Celular/fisiologia , Proteínas de Choque Térmico/genética , Homeostase , Mitocôndrias/fisiologia , Mutação
10.
Homeopathy ; 104(3): 197-204, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26143453

RESUMO

BACKGROUND: Diabetes mellitus is a common endocrine disorder characterized by hyperglycemia eventually resulting in long-term complications. Increased glycation of proteins is implicated in the pathogenesis of complications. For treatment of diabetes, Syzygium jambolanum and Cephalandra indica are frequently prescribed in homeopathy. However their role in glycation is not well elucidated. The present study aimed to evaluate the role of these homeopathic preparations in glycation induced structural modifications and further to examine their cellular protection ability. METHODS: In human erythrocytes, in vitro mother tincture and dilutions of S. jambolanum (Sj ф, 30c, 200c), C. indica (Ci ф, 30c, 200c) and standard antiglycator (AG) were compared and their antiglycation potential assessed by the estimating different markers of glycation (frcutosamines, carbonyls, bound sugar), structural modifications (free amino and thiol group). Phytochemical characterization (total phenolic, flavonoids and glycosides contents) was performed. RESULTS: The homeopathic preparations have different mode of action on albumin glycation modifications. Sj ф preparation demonstrated effective inhibition of all glycation, structural modifications except amino group protection. When dilutions were compared, Sj preparations showed reduction of glycation, structural modifications. All preparations showed significant erythrocyte protection. Sj ф preparation exhibited noteworthy antiglycation and cell protection ability as compared to AG. CONCLUSION: These homeopathic preparations especially Sj ф prevented glycation induced albumin modifications and subsequent toxicity in human eryrthrocytre in vitro. Further investigation of their potential as antiglycators is justified.


Assuntos
Dipsacaceae , Homeopatia/métodos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Albumina Sérica/antagonistas & inibidores , Syzygium , Eritrócitos/efeitos dos fármacos , Produtos Finais de Glicação Avançada , Humanos , Técnicas In Vitro , Extratos Vegetais/uso terapêutico , Substâncias Protetoras/uso terapêutico , Albumina Sérica Glicada
11.
Int J Biol Macromol ; 79: 601-10, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26027608

RESUMO

The present work aims to investigate the concentration and time dependant effect of zinc on the in vitro non enzymatic modifications of albumin by diabetic levels of glucose. Further, preventive and curative effect of zinc was studied by adding zinc before and after initiation of glycation respectively. Glycation of albumin was done at different concentrations of zinc (125, 250 and 500 µM) at different time intervals (21, 28 and 35 days) with appropriate controls. The antiglycation potential of zinc was assessed by estimating different markers of albumin glycation (fructosamines, carbonyls, bound sugar, AGEs), structural modifications (free amino, thiol group, ß amyloid, native PAGE, ANS binding, fluorescence lifetime decay and CD analysis) and functional properties (antioxidant activity, hemolysis). Zinc at highest concentration (500 µM) significantly reduced modifications of albumin which was comparable to aminoguanidine and also protected secondary and tertiary structure of albumin after 28 days of incubation. Zinc exhibited significant protective effect on erythrocytes by inhibiting hemolysis. Thus the present study indicate preventive mode of albumin glycation inhibition by zinc.


Assuntos
Eritrócitos/fisiologia , Soroalbumina Bovina/química , Zinco/farmacologia , Citoproteção , Avaliação Pré-Clínica de Medicamentos , Eritrócitos/efeitos dos fármacos , Glicosilação , Humanos , Processamento de Proteína Pós-Traducional
12.
J Food Sci Technol ; 52(4): 1911-23, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25829572

RESUMO

Azadirachta indica, Emblica officinalis, Syzygium cumini and Terminalia bellirica are common in Indian system of traditional medicine for the prevention of diabetes and its complications. The aim of the present study was to comprehensively and comparatively investigate the antiglycation potential of these plant extracts at multiple stages and their possible protective effect against glycated albumin mediated toxicity to erythrocytes. Antiglycation activities of these plant extracts was measured by co-incubation of plant extract with bovine serum albumin-fructose glycation model. The multistage glycation markers- fructosamines (early stage), protein carbonyls (intermediate stage) and AGEs (late stage) are investigated along with measurement of thiols and ß aggregation of albumin using amyloid-specific dyes-Congo red and Th T. Protection of erythrocytes from glycated albumin induced toxicity by these plant extracts was assessed by measuring erythrocytes hemolysis, lipid peroxidation, reduced glutathione and intracellular antioxidant capacity. Total phenolics, reducing power and antioxidant activities of the plant extracts were also measured. In vitro glycation assays showed that plant extracts exerted site specific inhibitory effects at multiple stages, with T. bellirica showing maximum attenuation. In erythrocytes, along with the retardation of glycated albumin induced hemolysis and lipid-peroxidation, T. bellirica considerably maintained cellular antioxidant potential. Significant positive correlations were observed between erythrocyte protection parameters with total phenolics. These plant extracts especially T. bellirica prevents glycation induced albumin modifications and subsequent toxicity to erythrocytes which might offer additional protection against diabetic vascular complications.

13.
Pharm Biol ; 53(1): 40-50, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25243884

RESUMO

CONTEXT: Glycated albumin is reported to elicit pathobiologic effects in diabetic nephropathy and abrogating its biologic effects has novel therapeutic potential. OBJECTIVE: This study examines the effects of dietary plants extracts (Laurus nobilis, Carum carvi, Coccinia grandis, Mentha arvensis, Phaseolus vulgaris) against albumin glycation and its toxicity to erythrocytes and HEK293 cells. MATERIALS AND METHODS: Albumin (10 mg/ml) was incubated with fructose (250 mM) in PBS along with aqueous plant extracts (1% w/v) for 4 d. After incubation, the antiglycation potential of extracts was estimated by measuring AGEs, fructosamine, amyloids, carbonyls, free amino groups, and antioxidant potential of albumin. The glycation extent of the treated samples was determined by boronate affinity chromatography. Effect of extracts against glycation induced cytotoxicity in erythrocytes and HEK 293 cells was assessed by estimating viability, glutathione, and antioxidant capacity. Plant extracts were tested for their phenolic content and antioxidant potential (reducing potential, DPPH, ABTS, NO, and H2O2 radical scavenging activities). RESULTS: Plant extracts significantly decreased the AGEs formation and amyloid aggregation in glycated BSA (p < 0.001). Further, fructosamine and carbonyls were reduced to 55-72% and 83-89%, respectively. Free amino group and antioxidant activity of albumin were also preserved by 1.25-1.40-fold and 1.75-1.8-fold, respectively. Further, co-incubation of extracts with glycated albumin, protected erythrocytes, and HEK293 cells as they inhibited cellular hemolysis/toxicity (p < 0.001) by upregulating cellular antioxidants. DISCUSSION AND CONCLUSION: Plant co-incubation reversed many modifications in albumin glycation, cellular dysfunction indicating that dietary sources with antiglycating and antioxidant potential could be considered for the effective management of diabetic nephropathy.


Assuntos
Antioxidantes/farmacologia , Nefropatias Diabéticas/prevenção & controle , Eritrócitos/efeitos dos fármacos , Produtos Finais de Glicação Avançada/metabolismo , Extratos Vegetais/farmacologia , Plantas Comestíveis/química , Antioxidantes/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Nefropatias Diabéticas/metabolismo , Eritrócitos/metabolismo , Glicosilação , Células HEK293 , Hemólise/efeitos dos fármacos , Humanos , Extratos Vegetais/isolamento & purificação , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo
14.
J Parkinsons Dis ; 3(3): 275-91, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24002224

RESUMO

Parkinson's disease (PD) is a neurodegenerative disease that is primarily characterized by degeneration of dopaminergic (DA) neurons in the substantia nigra (SN) and a loss of their fibre projections in the striatum. We utilized the neonatal porcine choroid plexus (CP), an organ that secretes cerebrospinal fluid containing various types of neurotrophic and neuroprotective factors, to ameliorate the Parkinsonian symptoms in MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-treated rhesus monkeys without requiring immunosuppression. We demonstrate that transplanted encapsulated CP clusters (eCPs) significantly improved neurological functions in MPTP-treated monkeys during the course of six months after transplantation (p < 0.001) when compared with monkeys implanted with empty capsules or subjected to sham surgery. The improvement in neurological scores was accompanied by a corresponding improvement in apomorphine-induced circling behaviour (p < 0.001) as well as increased tyrosine hydroxylase (TH) staining in the striatum. Our results suggest that eCPs are a promising cell therapeutic agent to treat Parkinson's disease.


Assuntos
Transplante de Células/métodos , Plexo Corióideo/citologia , Intoxicação por MPTP/cirurgia , Doença de Parkinson Secundária/cirurgia , Animais , Animais Recém-Nascidos , Apomorfina , Agonistas de Dopamina , Imuno-Histoquímica , Intoxicação por MPTP/patologia , Macaca mulatta , Masculino , Movimento/fisiologia , Neostriado/metabolismo , Rede Nervosa/citologia , Rede Nervosa/fisiologia , Exame Neurológico , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/patologia , Postura/fisiologia , Recuperação de Função Fisiológica , Rotação , Suínos , Tirosina 3-Mono-Oxigenase/metabolismo
15.
Anal Biochem ; 431(2): 90-5, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22929700

RESUMO

Gene expression studies often require inducible coexpression of both a gene of interest and a reporter gene. Fusion of fluorescent reporters can, however, modify protein structure and function. We have generated inducible expression systems for two connexin genes: Cx30 and Cx43. It has been reported recently that reporter fusion to connexins can modify their function. Therefore, we compared two methods of independent reporter coexpression and examined colocalization with induced connexin expression. Identical levels of connexin expression were observed for both the bidirectional and bicistronic expression systems. In contrast, however, reporter gene expression by the bidirectional promoter provided brighter average fluorescent pixel intensity than expression of a reporter gene in a bicistronic transcript. Moreover, as a result of this difference in reporter expression, bidirectional expression systems provided equal or better colocalization between the connexins and reporter gene fluorescence. The results of our study indicate that bidirectional reporter expression provides a robust indicator of transfection and gene expression and, therefore, may favor the use of bidirectional over bicistronic reporters in the design of expression systems where the gene of interest, such as a connexin gene, contains translational motifs or long intronic regions.


Assuntos
Conexina 43 , Conexinas , Expressão Gênica , Genes Reporter , Conexina 30 , Conexina 43/genética , Conexina 43/metabolismo , Conexinas/genética , Conexinas/metabolismo , Proteínas de Fluorescência Verde/genética , Humanos , Regiões Promotoras Genéticas
16.
Neurochem Int ; 60(6): 640-51, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22417726

RESUMO

Microglial activation is a significant contributor to the pathogenesis of many neurodegenerative diseases. Microglia respond to a range of stimuli including pathogenic protein deposits such as advanced glycation endproducts (AGEs). AGEs are prominent inflammatory stimuli that accumulate in the ageing brain. AGEs can activate microglia, leading to the production of excessive amounts of inflammatory cytokines and coupling via gap junction proteins especially connexin43 (Cx43). The literature on the expression of microglial Cx43 during inflammation is controversial. Many cellular effects of AGEs are thought to be mediated by the receptor RAGE. There is however, no evidence suggesting Cx43 is a downstream effector of AGEs-RAGE interaction in microglia. In addition, most of the AGEs-related studies have been undertaken using rodent microglia; the information on human microglia is sparse. Microglia of human and rodent origin respond differently to certain stimuli. The aims of this study were to investigate the AGEs-RAGE-mediated activation of human microglia and establish if Cx43 is one of the downstream effectors of AGEs-RAGE interaction in these cells. Human microglial CHME-5 cells were treated with different doses of AGEs for a selected time-period and microglial activation studied using specific markers. The protein expression of RAGE, Cx43 and TNF-α-receptors (RI and RII) was analysed in response to AGEs in the absence/presence of various doses of anti-RAGE Fabs. TNF-α levels in media were measured using ELISA. TNF-α-induced opening of gap junctional channels was assessed by dye uptake assays and the effect of neutralising TNFRII on Cx43 levels was also studied. CHME-5 cells showed an up-regulation of RAGE, TNF-α, TNFRs (especially TNFRII) and Cx43 upon AGEs treatment and a significant dose-dependent drop in the levels of TNF-α, TNFRII and Cx43 in the presence of anti-RAGE Fabs. TNF-α induced gap junctional/hemichannel opening whereas blocking TNFRII inhibited TNF-α-induced increase in Cx43 levels. Results suggested that TNF-α, TNFRII and Cx43 are downstream effectors of the AGEs-RAGE interaction in human microglial CHME-5 cells.


Assuntos
Conexina 43/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Microglia/metabolismo , Receptores Imunológicos/metabolismo , Animais , Linhagem Celular Transformada , Produtos Finais de Glicação Avançada/farmacologia , Humanos , Microglia/citologia , Microglia/efeitos dos fármacos , Receptor para Produtos Finais de Glicação Avançada , Roedores , Especificidade da Espécie , Regulação para Cima/fisiologia
17.
J Neurosci Res ; 90(6): 1136-47, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22344976

RESUMO

The receptor for advanced glycation end products (RAGE) is a multiligand receptor protein thought to play an important role in neuronal differentiation. RAGE can bind a number of ligands and activate a variety of signalling pathways that lead to diverse downstream effects. Amphoterin and S100B are endogenous ligands, the interaction of which with RAGE is known to be involved in defined physiological processes. The present study investigated the spatiotemporal pattern of the expression for RAGE and its ligands, amphoterin and S100B, during neuronal differentiation of NT2/D1 cells. In this study, all three proteins were shown to increase with progression of neuronal differentiation as determined by Western blotting, raising the possibility that both amphoterin and S100B may interact with RAGE and have important functions during the process of cell differentiation. Moreover, blocking the activation of RAGE with neutralizing antibody in the presence of retinoic acid disrupted the progression of normal neuronal differentiation. Immunocytochemistry (ICC) studies showed that amphoterin partially colocalized with RAGE within differentiating NT2 cells, whereas S100B showed a high degree of colocalization. This result suggests that S100B is more likely to be the principal ligand for RAGE during the differentiation process and that RAGE and amphoterin might have both independent and combined roles. Moreover, RAGE was expressed only in cells that were committed to a neuronal phenotype, suggesting direct involvement of RAGE in mediating cellular changes within differentiating neuronal cells. Further detailed studies are now required to characterize fully the role of RAGE during the neuronal differentiation period.


Assuntos
Diferenciação Celular/fisiologia , Neurônios/fisiologia , Receptores Imunológicos/fisiologia , Anticorpos/farmacologia , Antineoplásicos/farmacologia , Carcinoma/patologia , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Humanos , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Neurônios/efeitos dos fármacos , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/imunologia , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/genética , Proteínas S100/metabolismo , Tretinoína/farmacologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
18.
J Biomol Tech ; 22(3): 95-107, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21966257

RESUMO

Reactive oxygen species (ROS) are generated continuously during aerobic metabolism. ROS are highly reactive molecules and in excessive amounts, can lead to protein and DNA oxidation, protein cross-linking, and cell death. Cell-culture models provide a valuable tool in understanding the mechanisms that lead to cell death. Accumulation of ROS within cells and/or their release into the culture media are highly cell type-specific. The ability to estimate ROS levels in the culture media is an important step in understanding the mechanisms contributing to disease processes. In this paper, we describe the optimization of a simple method to estimate ROS levels in the culture media using the Acridan Lumigen PS-3 reagent provided in the Amersham ECL Plus kit (GE Healthcare, UK). We have shown that the Acridan Lumigen PS-3 assay generates ROS-specific chemiluminescence in fresh as well as media stored at -20°C, in as little as 10-20 µl of samples. The method was able to detect the dose (of stimulants)- and time (acute and chronic)-dependent changes in ROS levels in media collected from various cell types. Our results suggest that the kit reagents, PBS buffer, and various media did not contribute significantly to the overall chemiluminescence generated in the assay; however, we suggest that the unused medium specific for each cell type should be used as blanks and final readings of test samples normalized against these readings. As this method uses commonly available laboratory equipment and commercially available reagents, we believe this assay is convenient, economical, and specific in estimating ROS released extracellularly into the culture media.


Assuntos
Acridinas/química , Técnicas de Química Analítica , Meios de Cultivo Condicionados/química , Indicadores e Reagentes/química , Espécies Reativas de Oxigênio/química , Animais , Soluções Tampão , Linhagem Celular , Relação Dose-Resposta a Droga , Humanos , Luminescência , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Cultura Primária de Células , Ratos , Ratos Wistar , Rotenona/farmacologia , Sensibilidade e Especificidade
19.
Food Microbiol ; 26(8): 801-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19835764

RESUMO

The natural Saccharomyces and non-Saccharomyces yeast flora present on the grape berries significantly affect wine production. Six grape varieties, Bangalore blue, Zinfandel, Cabernet, Chenin Blanc, Sauvignon Blanc and Shiraz are being used in India for wine making. The yeast diversity was studied on the basis of morphological, colony, physiological characteristics and 5.8S-ITS sequencing of rDNA of the isolates. Eleven different species belonging to seven genera were identified as: Candida azyma, Candida quercitrusa, Debaryomyces hansenii, Hanseniaspora guilliermondii, Hanseniaspora viniae, Hanseniaspora uvarum, Issatchenkia orientalis, Issatchenkia terricola, Pichia membranifaciens, Saccharomyces cerevisiae and Zygoascus steatolyticus. H. guilliermondii was the predominant species while S. cerevisiae was observed occasionally in the six vine varieties. For the first time, C. azyma was isolated from Bangalore blue and Cabernet varieties grown in different localities. This association may be attributed to the change in cropping pattern from sugarcane to viticulture in the vine growing regions and the known association of C. azyma with sugarcane phylloplane. Further analysis of the indigenous strains and the qualitative and quantitative changes in the flora during fermentation will be useful to understand wine quality and to design preservation strategies to control wine spoilage.


Assuntos
Filogenia , Vitis/classificação , Vitis/microbiologia , Vinho/microbiologia , Leveduras/classificação , Leveduras/fisiologia , DNA Fúngico/análise , DNA Espaçador Ribossômico/análise , Fermentação , Índia , Microbiologia Industrial , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , RNA Ribossômico 5,8S/análise , Análise de Sequência de DNA , Especificidade da Espécie
20.
Mol Neurodegener ; 4: 55, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-20042120

RESUMO

BACKGROUND: Exposure to toxins/chemicals is considered to be a significant risk factor in the pathogenesis of Parkinson's disease (PD); one putative chemical is the naturally occurring herbicide rotenone that is now used widely in establishing PD models. We, and others, have shown that chronic low dose rotenone treatment induces excessive accumulation of Reactive Oxygen Species (ROS), inclusion body formation and apoptosis in dopaminergic neurons of animal and human origin. Some studies have also suggested that microglia enhance the rotenone induced neurotoxicity. While the effects of rotenone on neurons are well established, there is little or no information available on the effect of rotenone on microglial cells, and especially cells of human origin. The aim of the present study was to investigate the effects of chronic low dose rotenone treatment on human microglial CHME-5 cells. METHODS: We have shown previously that rotenone induced inclusion body formation in human dopaminergic SH-SY5Y cells and therefore used these cells as a control for inclusion body formation in this study. SH-SY5Y and CHME-5 cells were treated with 5 nM rotenone for four weeks. At the end of week 4, both cell types were analysed for the presence of inclusion bodies, superoxide dismutases and cell activation (only in CHME-5 cells) using Haematoxylin and Eosin staining, immunocytochemical and western blotting methods. Levels of active caspases and ROS (both extra and intra cellular) were measured using biochemical methods. CONCLUSION: The results suggest that chronic low dose rotenone treatment activates human microglia (cell line) in a manner similar to microglia of animal origin as shown by others. However human microglia release excessive amounts of ROS extracellularly, do not show excessive amounts of intracellular ROS and active caspases and most importantly do not show any protein aggregation or inclusion body formation. Human microglia appear to be resistant to rotenone (chronic, low dose) induced damage.

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