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1.
Arch Microbiol ; 206(5): 205, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573383

RESUMO

Honeybees are vital for global crop pollination, making indispensable contributions to agricultural productivity. However, these vital insects are currently facing escalating colony losses on a global scale, primarily attributed to parasitic and pathogenic attacks. The prevalent response to combat these infections may involve the use of antibiotics. Nevertheless, the application of antibiotics raises concerns regarding potential adverse effects such as antibiotic resistance and imbalances in the gut microbiota of bees. In response to these challenges, this study reviews the utilization of a probiotic-supplemented pollen substitute diet to promote honeybee gut health, enhance immunity, and overall well-being. We systematically explore various probiotic strains and their impacts on critical parameters, including survival rate, colony strength, honey and royal jelly production, and the immune response of bees. By doing so, we emphasize the significance of maintaining a balanced gut microbial community in honeybees. The review also scrutinizes the factors influencing the gut microbial communities of bees, elucidates the consequences of dysbiosis, and evaluates the potential of probiotics to mitigate these challenges. Additionally, it delineates different delivery mechanisms for probiotic supplementation and elucidates their positive effects on diverse health parameters of honeybees. Given the alarming decline in honeybee populations and the consequential threat to global food security, this study provides valuable insights into sustainable practices aimed at supporting honeybee populations and enhancing agricultural productivity.


Assuntos
Criação de Abelhas , Probióticos , Abelhas , Animais , Agricultura , Antibacterianos , Disbiose
2.
J Pharm Pharmacol ; 75(6): 859-872, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37134308

RESUMO

OBJECTIVES: The aim of this study was to investigate the potential of poly(amido amine) (PAMAM) dendrimer decorated graphene oxide (GO) based nanocarrier for targeted delivery of a hydrophobic anticancer drug, quercetin (QSR). METHODS: GO-PAMAM was successfully synthesized by covalent bonding between GO and NH2-terminated PAMAM dendrimer (zero generation). To investigate drug loading performance, QSR was loaded on the surface of GO as well as GO-PAMAM. Further, the release behaviour of QSR-loaded GO-PAMAM was studied. Finally, an in-vitro sulforhodamine B assay was performed in HEK 293T epithelial cells and MDA MB 231 breast cancer cells. KEY FINDINGS: It was observed that GO-PAMAM shows higher QSR loading capacity compared to GO. Also, synthesized nanocarrier exhibits controlled as well as pH-responsive release of QSR and the amount of QSR released at pH 4 was approximately two times higher than the release at pH 7.4. Furthermore, GO-PAMAM was found to be biocompatible for HEK 293T cells, and a high cytotoxic effect was observed for QSR-loaded GO-PAMAM on MDA MB 231 cells. CONCLUSIONS: The present investigation highlights the potential application of synthesized hybrid materials as a nanocarrier with excellent loading and controlled releasing efficiency for the delivery of the hydrophobic anticancer drug.


Assuntos
Antineoplásicos , Neoplasias da Mama , Dendrímeros , Humanos , Feminino , Dendrímeros/química , Dendrímeros/farmacologia , Neoplasias da Mama/tratamento farmacológico , Quercetina/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Concentração de Íons de Hidrogênio , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos
3.
Curr Drug Deliv ; 20(7): 943-950, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35611774

RESUMO

BACKGROUND: The combinatorial use of anticancer drugs, dual or multiple, with a specific nanocarrier is one of the most promising attempts in drug delivery. The current work reports potassium contained graphene oxide (K-GO) as a nanocarrier in the drug delivery system of two anticancer drugs, gefitinib (GEF) and camptothecin (CPT), simultaneously. METHODS: To characterize K-GO, K-GO-related single and combined drug systems, different techniques have been performed and studied using the following spectroscopic tools, such as Thermo Gravimetric Analysis (TGA 4000), UV-visible spectroscopy, Raman spectroscopy, and Transmission electron microscopy (TEM). The in vitro cytotoxicity tests of K-GO, single drug system, and the combined drug system were also performed in the human breast cancer MDA-MB-231 cells. RESULTS: The release profile of the dual drug conjugates grafted onto the surface of K-GO was found to be up to 38% in PBS solution over 72 hours. The percentage of MDA-MB-231 cell viability was about 18% when treated with K-GO-GEF-CPT combined system; for K-GO, K-GO-GEF, and K-GO-CPT, the cell viability was 79%, 31%, and 32%, respectively. CONCLUSION: We studied the loading, release, and delivery of two anticancer drugs onto the fluorescent nanocarrier. Features, such as superb aqueous solubility, excellent biocompatibility, richness in potassium, and fluorescent nature, which can monitor the delivery of drugs, make them a promising nanocarrier for single or multiple drug delivery. Furthermore, our novel findings revealed that the loading capacity and cytotoxicity of the combined drug-loaded system are superior to the capacity of the individual drug system for human breast cancer cells.


Assuntos
Antineoplásicos , Neoplasias da Mama , Grafite , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Preparações Farmacêuticas , Sistemas de Liberação de Medicamentos/métodos , Antineoplásicos/química , Gefitinibe , Portadores de Fármacos/química
4.
Front Plant Sci ; 13: 963150, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36092393

RESUMO

The study was undertaken to characterize the total phenolics, flavonoids, essential oils, quinones, tannins and antioxidant activity of 15 samples of wild Murraya koenigii (L.) Spreng. (MK) leaves obtained from different locations of Himachal Pradesh at various growth stages. The results indicated a significant variation in total phenolic content which ranged from [(170.09 ± 4.59 to 303.57 ± 7.94) in pre-flowering, (266.48 ± 7.49 to 450.01 ± 11.78) in the flowering stage, and (212.72 ± 5.37 to 363.85 ± 9.79) in fruiting stage], expressed as mg tannic acid equivalents (TAE)/g. The total flavonoid content ranged from [(15.17 ± 0.36 to 33.40 ± 0.81) in pre-flowering, (25.16 ± 0.67 to 58.17 ± 1.52) in flowering stage, and (17.54 ± 0.42 to 37.34 ± 0.97) in fruiting stage], expressed as mg catechin equivalent (CE)/g. Total tannin content ranged from [(75.75 ± 1.69 to 143 ± 3.74) in pre-flowering, (116 ± 3.26 to 207 ± 5.42) in the flowering stage, and (47 ± 1.18 to 156 ± 4.05) in fruiting stage], expressed as mg TAE/g. The essential oil content ranged from (0.64 ± 0.01 to 0.89 ± 0.02%) in pre-flowering, (0.85 ± 0.02 to 1 ± 0.02%) in flowering stage, and (0.54 ± 0.01 to 0.7 ± 0.01%) in fruiting stage. Quinones ranged from [(2.05 ± 0.05 to 2.97 ± 0.07) in pre-flowering, (3.07 ± 0.07 to 4.95 ± 0.13) in flowering stage, and (1.02 ± 0.02 to 1.96 ± 0.04) in fruiting stage], expressed as mM/min/g tissue. Antioxidant activity ranged from [(4.01 ± 0.09 to 7.42 ± 0.17) in pre-flowering, (8.08 ± 0.19 to 13.60 ± 0.35) in flowering stage, and (3.11 ± 0.06 to 6.37 ± 0.15) in fruiting stage], expressed as µg/ml. Data was subjected to multivariate analysis using principal component analysis (PCA), hierarchical clustering analysis (HCA). This was used for elucidating the intricate relationships between the phytochemical properties. All evaluated phytochemical parameters significantly increased during the growth transition from pre-flowering to the flowering stage, followed by their gradual decrease during the fruiting stage. The present study can serve as rationale for commercializing MK for aromatic and phytopharmaceutical industries.

5.
RSC Adv ; 12(5): 2574-2588, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35425302

RESUMO

In this work, polymer grafted magnetic graphene oxide (GO-PVP-Fe3O4) was successfully synthesized for efficient delivery of anticancer drug. Firstly, GO was functionalized with the hydrophilic and biocompatible polymer polyvinylpyrrolidone (PVP) and then grafted with magnetic nanoparticles (Fe3O4) through an easy and effective chemical co-precipitation method. Quercetin (QSR) as an anticancer drug was loaded onto the surface of GO-PVP-Fe3O4 via non-covalent interactions. The drug loading capacity was as high as 1.69 mg mg-1 and the synthesized magnetic nanocarrier shows pH-responsive controlled release of QSR. The cellular cytotoxicity of the synthesized nanocarrier with and without drugs was investigated in human breast cancer MDA MB 231 cells and their effects compared on non-tumorigenic epithelial HEK 293T cells. These results reveal that the drug loaded GO-PVP-Fe3O4 nanohybrid was found to be more toxic than the free drug towards MDA MB 231 cells and exhibits biocompatibility towards HEK 293T cells. Overall, a smart drug delivery system including polymer grafted magnetic graphene oxide as a pH-responsive potential nanocarrier could be beneficial for targeted drug delivery, controlled by an external magnetic field as an advancement in chemotherapy against cancer.

6.
Curr Pharm Biotechnol ; 23(7): 904-919, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34387160

RESUMO

Natural products have widely been used in applications ranging from antibacterial, antiviral, antifungal, and various other medicinal applications. The use of these natural products was recognized way before the establishment of basic chemistry behind the disease and the chemistry of plant metabo-lites. After the establishment of plant chemistry, various new horizons evolved, and the application of natural products breached the orthodox limitations. In one such interdisciplinary area, the use of plant materials in the synthesis of nanoparticles (NPs) has exponentially emerged. This advancement has offered various environment-friendly methods where hazardous chemicals are completely replaced by natural products in the sophisticated and hectic synthesis processes. This review is an attempt to under-stand the mechanism of metal nanoparticles synthesis using plant materials. It includes details on the role of the plant's secondary metabolites in the synthesis of nanoparticles including the mechanism of action. In addition, the use of these nanomaterials has widely been discussed along with the possible mechanism behind their antimicrobial and catalytic action.


Assuntos
Anti-Infecciosos , Produtos Biológicos , Nanopartículas Metálicas , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Química Verde , Extratos Vegetais/farmacologia
7.
Genetics ; 219(2)2021 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-34849876

RESUMO

Understanding how mutations affect survivability is a key component to knowing how organisms and complex traits evolve. However, most mutations have a minor effect on fitness and these effects are difficult to resolve using traditional molecular techniques. Therefore, there is a dire need for more accurate and precise fitness measurements methods. Here, we measured the fitness effects in Burkholderia cenocepacia HI2424 mutation accumulation (MA) lines using droplet-digital polymerase chain reaction (ddPCR). Overall, the fitness measurements from ddPCR-MA are correlated positively with fitness measurements derived from traditional phenotypic marker assays (r = 0.297, P = 0.05), but showed some differences. First, ddPCR had significantly lower measurement variance in fitness (F = 3.78, P < 2.6 × 10-13) in control experiments. Second, the mean fitness from ddPCR-MA measurements were significantly lower than phenotypic marker assays (-0.0041 vs -0.0071, P = 0.006). Consistent with phenotypic marker assays, ddPCR-MA measurements observed multiple (27/43) lineages that significantly deviated from mean fitness, suggesting that a majority of the mutations are neutral or slightly deleterious and intermixed with a few mutations that have extremely large effects. Of these mutations, we found a significant excess of mutations within DNA excinuclease and Lys R transcriptional regulators that have extreme deleterious and beneficial effects, indicating that modifications to transcription and replication may have a strong effect on organismal fitness. This study demonstrates the power of ddPCR as a ubiquitous method for high-throughput fitness measurements in both DNA- and RNA-based organisms regardless of cell type or physiology.


Assuntos
Burkholderia cenocepacia/genética , Aptidão Genética , Acúmulo de Mutações , Taxa de Mutação , Fenótipo , Reação em Cadeia da Polimerase/métodos
8.
J Mater Chem B ; 8(36): 8116-8148, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32966535

RESUMO

Graphene oxide (GO) has attracted tremendous attention as a most promising nanomaterial among the carbon family since it emerged as a polynomial functional tool with rational applications in diverse fields such as biomedical engineering, electrocatalysis, biosensing, energy conversion, and storage devices. Despite having certain limitations due to its irreversible aggregation performance owing largely to the strong van der Waals interactions, efforts have been made to smartly engineer its surface chemistry for realistic multimodal applications. The use of such GO-based engineered devices has increased rapidly in the last few years, principally due to its excellent properties, such as huge surface area, honeycomb-like structure allowing vacant interstitial space to accommodate compounds, sp2 hybridized carbon, improved biocompatibility and cell surface penetration due to electronic interactions. Amongst multifaceted GO dynamics, in this review, attempts are made to discuss the advanced applications of GO or graphene-based materials (GBNs) in the biomedical field involving drug or therapeutic gene delivery, dual drug or drug-gene combination targeting, special delivery of drug cocktails to the brain, stimuli-responsive release of molecular payloads, and Janus-structured smart applications for polar-nonpolar combination drug loading followed by targeting together with smart bioimaging approaches. In addition, the advantages of duel-drug delivery systems are discussed in detail. We also discuss various electronic mechanisms, and detailed surface engineering to meet microcosmic criteria for its utilization, various novel implementations of engineered GO as mentioned above, together with discussions of its inevitable toxicity or disadvantages. We hope that the target audience, belonging to biomedical engineering, pharmaceutical or material science fields, may acquire relevant information from this review which may help them design future studies in this field.


Assuntos
Portadores de Fármacos/química , Grafite/química , Imagem Óptica/métodos , Farmacologia/métodos , Animais , Liberação Controlada de Fármacos , Técnicas de Transferência de Genes , Nanopartículas Metálicas/química , Polímeros/química
9.
Am J Hypertens ; 31(11): 1234-1242, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30084918

RESUMO

BACKGROUND: The contribution of single nucleotide polymorphisms in transcriptional regulation of the human angiotensin receptor type I (hAT1R) gene in age-related chronic pathologies such as hypertension and associated renal disorders is not well known. The hAT1R gene has single nucleotide polymorphisms in its promoter that forms 2 haplotypes (Hap), Hap-I and Hap-II. Hap-I of AT1R gene is associated with hypertension in Caucasians. We have hypothesized here that age will alter the transcriptional environment of the cell and will regulate the expression of hAT1R gene in a haplotype-dependent manner. This could likely make subjects with Hap-I increasingly susceptible to age-associated, AT1R-mediated complications. METHOD: We generated transgenic (TG) mice with Hap-I and Hap-II. Adults (10-12 weeks) and aged (20-24 months) TG male mice containing either Hap-I or Hap-II were divided into 4 groups to study (i) the age-associated and haplotype-specific transcriptional regulation of hAT1R gene and (ii) their physiological relevance. RESULTS: In aged animals, TG mice with Hap-I show increased expression of hAT1R and higher blood pressure (BP); suppression of antioxidant defenses (hemoxygenase, superoxide dismutase) and antiaging molecules (ATRAP, Klotho, Sirt3); increased expression of pro-inflammatory markers (IL-6, TNFα, CRP, NOX1); and increased insulin resistance. In vivo ChIP assay shows stronger binding of transcription factor USF2 to the chromatin of Hap-I mice. CONCLUSION: Our results suggest that in aged animals, as compared with Hap-II, the TG mice with Hap-I overexpress hAT1R gene due to the stronger transcriptional activity, thus resulting in an increase in their BP and associated renal disorders.


Assuntos
Envelhecimento/genética , Rim/fisiopatologia , Polimorfismo de Nucleotídeo Único , Receptor Tipo 1 de Angiotensina/genética , Envelhecimento/metabolismo , Animais , Sítios de Ligação , Pressão Sanguínea , Regulação da Expressão Gênica , Predisposição Genética para Doença , Haplótipos , Humanos , Rim/metabolismo , Masculino , Camundongos Transgênicos , Fenótipo , Regiões Promotoras Genéticas , RNA Polimerase II/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Fatores Estimuladores Upstream/metabolismo
10.
Am J Hypertens ; 31(4): 495-503, 2018 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-29036458

RESUMO

BACKGROUND: The transcriptional regulation of the human angiotensin receptor subtype 1 (AT1R) gene in pathophysiologies, like the metabolic syndrome, is poorly understood. The human AT1R gene has polymorphisms in its promoter that can be arranged in 2 haplotypes. Variants -810T, -713T, -214A, and -153A always occur together (Hap-I) and variants -810A, -713G, -214C, and -153G form Hap-II. We have hypothesized that high fat diet will alter cellular transcriptional milieu and increase hAT1R gene expression in a haplotype-dependent manner. This will set up an AT1R-mediated feed-forward loop promoting inflammation, oxidative stress, and hypertension in Hap-I mice. METHOD: Since Hap-I of the human AT1R gene is associated with hypertension in Caucasians, we generated transgenic (TG) mice with Hap-I and Hap-II and studied the physiological significance of high fat diet (HFD) on haplotype specific gene expression. Animals were fed with HFD for 20 weeks followed by blood pressure (BP) analysis and collection of their tissues for molecular and biochemical studies. RESULTS: After HFD treatment, as compared to Hap-II, TG mice with Hap-I show increased expression of hAT1R gene and higher BP; suppression of antioxidant defenses (HO1, SOD1) and increased expression of IL-6, TNFα, IL-1ß, NOX1. In vivo ChIP assay has shown that transcription factors CEBPß, STAT3, and USF bind more strongly to the chromatin obtained from Hap-I TG mice. CONCLUSIONS: Taken together, our results suggest, that after HFD treatment, as compared to Hap-II, the TG mice with Hap-I overexpress the AT1R gene due to the stronger transcriptional activity, thus resulting in an increase in their BP.


Assuntos
Pressão Sanguínea/genética , Hipertensão/genética , Síndrome Metabólica/genética , Polimorfismo Genético , Receptor Tipo 1 de Angiotensina/genética , Adulto , Animais , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Feminino , Predisposição Genética para Doença , Haplótipos , Frequência Cardíaca/genética , Humanos , Hipertensão/diagnóstico , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Mediadores da Inflamação/metabolismo , Rim/metabolismo , Rim/fisiopatologia , Masculino , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/metabolismo , Síndrome Metabólica/fisiopatologia , Camundongos Transgênicos , Pessoa de Meia-Idade , Fenótipo , Regiões Promotoras Genéticas , Fator de Transcrição STAT3/metabolismo , Transcrição Gênica , Ativação Transcricional , Fatores Estimuladores Upstream/metabolismo
11.
PLoS One ; 12(5): e0176373, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28467442

RESUMO

Single nucleotide polymorphisms (SNPs) in the human angiotensinogen (hAGT) gene may modulate its transcription and affect the regulation of blood pressure via activation of the renin-angiotensin aldosterone system (RAAS). In this regard, we have identified polymorphisms in the 2.5 Kb promoter of the hAGT gene that form two haplotype (Hap) blocks: -6A/G (-1670A/G, -1562C/T, -1561T/C) and -217A/G (-532T/C, -793A/G, -1074T/C & -1178G/A). hAGT gene with Hap -6A/-217A (Hap I) is associated with increased blood pressure whereas, Hap -6G/-217G (Hap II) is associated with normal blood pressure in human subjects. Since RAAS over activity contributes to hypertension in obesity, we have made transgenic mice (TG) containing either Hap I or Hap II of the hAGT gene to understand the role of obesity on its transcriptional regulation. Although, a high-fat diet (60% Kcal from fat, 12 weeks) elevates hAGT and mAGT regardless of haplotype, this effect is significantly (p<0.05) accentuated in Hap I mice, in both adipose and liver tissues. Chromatin Immuno- precipitation (ChIP) assay shows an increased binding of transcription factors including, GR, CEBPß and STAT3 to the chromatin of the Hap I TG mice after high-fat diet as compared to Hap II TG mice (p<0.05). Differential plasma levels of hAGT in Hap II and I mice, after high-fat diet, further corroborate the variable transcriptional regulation of the hAGT, governed by gene-haplotypes. Taken together, our results show that SNPs in the Hap-I of the hAGT gene promote high-fat diet-induced binding of transcription factors GR, CEBP-ß and STAT3, which lead to elevated expression of the hAGT gene in hepatic and adipose tissues.


Assuntos
Angiotensinogênio/genética , Dieta Hiperlipídica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Haplótipos , Hipertensão/genética , Transcrição Gênica , Humanos
12.
Mol Neurobiol ; 53(3): 1533-1539, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25652270

RESUMO

Hypertension is one of the co-morbid conditions for stroke and profoundly increases its incidence. Angiotensin II (AngII) is shown to be at the center stage in driving the renin angiotensin system via activation of angiotensin 1 receptor (AT1R). This makes the AT1R gene one of the candidates whose differential regulation leads to the predisposition to disorders associated with hypertension. A haplotype block of four SNPs is represented primarily by haplotype-I, or Hap-I (TTAA), and haplotype-II, or Hap-II (AGCG), in the promoter of human AT1R (hAT1R) gene. To better understand the physiological role of these haplotypes, transgenic (TG) mice containing Hap-I and Hap-II of the hAT1R gene in a 166-kb bacterial artificial chromosome (BAC) were generated. Mice received injection of endothelin-1 (1 mg/ml) directly in to the striatum and were evaluated for neurologic deficit scores and sacrificed for analysis of infarct volume and mRNA levels of various proteins. Mice containing Hap-I suffered from significantly higher neurological deficits and larger brain infarcts than Hap II. Similarly, the molecular analysis of oxidant and inflammatory markers in brains of mice showed a significant increase (p < 0.05) in NOX-1 (2.3-fold), CRP (4.3-fold), and IL6 (1.9-fold) and a corresponding reduced expression of antioxidants SOD (60%) and HO1 (55%) in Hap-I mice as compared to Hap-II mice. These results suggest that increased expression of hAT1R rendered Hap-I TG mice susceptible to stroke-related pathology, possibly due to increased level of brain inflammatory and oxidative stress markers and a suppressed antioxidant defense system.


Assuntos
Receptor Tipo 1 de Angiotensina/fisiologia , Acidente Vascular Cerebral/genética , Animais , Corpo Estriado/efeitos dos fármacos , Endotelina-1/toxicidade , Haplótipos , Humanos , Interleucina-6/análise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NADH NADPH Oxirredutases/análise , NADPH Oxidase 1 , Proteínas do Tecido Nervoso/análise , Estresse Oxidativo , Receptor Tipo 1 de Angiotensina/genética , Proteínas Recombinantes de Fusão/metabolismo , Superóxido Dismutase-1/análise
13.
J Biol Chem ; 290(9): 5749-58, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25568318

RESUMO

The human angiotensinogen (hAGT) gene has polymorphisms in its 2.5-kb promoter that form two haplotype (Hap) blocks: -6A/G (-1670A/G, -1562C/T, and -1561T/C) and -217A/G (-532T/C, -793A/G, -1074T/C, and -1178G/A). Hap -6A/-217A is associated with human hypertension, whereas Hap -6G/-217G reduces cardiovascular risk. Hap -6A/-217A has increased promoter activity with enhanced transcription factor binding, including to the glucocorticoid receptor (GR). Glucocorticoid therapy frequently causes hypertension, the mechanisms for which are incompletely understood. We have engineered double transgenic (TG) mice containing the human renin gene with either Hap of the hAGT gene and examined the physiological significance of glucocorticoid-mediated allele-specific regulation of the hAGT gene. We have also studied the consequential effects on the renin angiotensin system and blood pressure. TG mice with Hap -6A and -6G were treated with and without a low dose of a GR agonist, dexamethasone (2.5 µg/ml), for 72 h. We found greater chromatin-GR binding with increased GR agonist-induced hAGT expression in liver and renal tissues of Hap -6A mice. Additionally, dexamethasone treatment increased circulating hAGT and angiotensin II levels in Hap -6A mice, as compared with -6G mice. Importantly, GR agonist significantly increased blood pressure and redox markers in TG mice with Hap-6A of the hAGT gene. Taken together, our results show, for the first time, that glucocorticoids affect hAGT expression in a haplotype-dependent fashion with SNPs in Hap -6A favoring agonist-induced GR binding. This leads to increased expression of the hAGT, up-regulation of the renin angiotensin system, and increased blood pressure and oxidative stress in Hap -6A mice.


Assuntos
Angiotensinogênio/genética , Dexametasona/farmacologia , Expressão Gênica/efeitos dos fármacos , Hipertensão/genética , Polimorfismo de Nucleotídeo Único , Alelos , Angiotensina II/sangue , Angiotensinogênio/sangue , Angiotensinogênio/metabolismo , Animais , Pressão Sanguínea/genética , Pressão Sanguínea/fisiologia , Predisposição Genética para Doença/genética , Glucocorticoides/farmacologia , Haplótipos , Humanos , Hipertensão/fisiopatologia , Immunoblotting , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Estresse Oxidativo/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/genética , Receptores de Glucocorticoides/agonistas , Receptores de Glucocorticoides/metabolismo , Sistema Renina-Angiotensina/genética , Sistema Renina-Angiotensina/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1
14.
Circ Cardiovasc Genet ; 8(1): 30-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25504670

RESUMO

BACKGROUND: Aldosterone, synthesized in the adrenal cortex by the enzyme CYP11B2, induces positive sodium balance and predisposes to hypertension. Various investigators, using genomic DNA analyses, have linked -344T polymorphism in the human CYP11B2 (hCYP11B2) gene to human hypertension. hCYP11B2 gene promoter has 3 single-nucleotide polymorphisms in linkage disequilibrium: T/A at -663, T/C at -470, and C/T at -344. Variants ACT occur together and form the haplotype-I (Hap-I), whereas variants TTC constitute Hap-II. We hypothesize that these single-nucleotide polymorphisms, when present together, will lead to haplotype-dependent differences in the transcriptional regulation of the hCYP11B2 gene and affect blood pressure regulation. METHODS AND RESULTS: We evaluated differences in tissue expression in vivo and consequential effects on blood pressure stemming from the 2 haplotypes. Novel transgenic mice with the hCYP11B2 gene, targeted to the mouse HPRT locus, with either Hap-II or Hap-I variant are used in this study. Our results show increased adrenal and renal expression of hCYP11B2 in transgenic mice with Hap-I when compared with mice with Hap-II. Importantly, we observed increased baseline blood pressure in Hap-I transgenic mice, an effect accentuated by a high-salt diet. Pathophysiological effects of elevated aldosterone were corroborated by our results showing upregulation of proinflammatory markers in renal tissues from the transgenic mice with Hap-I. CONCLUSIONS: These findings characterize the haplotype-dependent regulation of the hCYP11B2 gene where -344T serves as a reporter polymorphism and show that Hap-I leads to increased expression of hCYP11B2, with permissive effects on blood pressure and inflammatory milieu.


Assuntos
Citocromo P-450 CYP11B2 , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hipertensão , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Cloreto de Sódio na Dieta/efeitos adversos , Animais , Citocromo P-450 CYP11B2/biossíntese , Citocromo P-450 CYP11B2/genética , Humanos , Hipertensão/induzido quimicamente , Hipertensão/enzimologia , Hipertensão/genética , Hipertensão/fisiopatologia , Camundongos , Cloreto de Sódio na Dieta/farmacologia
15.
Support Care Cancer ; 22(7): 1773-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24522744

RESUMO

PURPOSE: Prevalence data of herpes simplex virus (HSV) in oral mucositis in children on treatment for cancer is limited. Quantitative polymerase chain reaction (PCR) has been seldom utilized for detection of HSV-1/2 in oral mucosa. METHODS: Children on treatment for cancer with oral mucositis were enrolled as cases and healthy children as controls. An oral swab from the lesion in cases and mucosal scraping in controls were obtained. Both qualitative and real-time quantitative PCR for HSV-1/2 were performed. Serum ELISA-IgG/IgM for HSV-1/2 antibodies (NovaLisa™-Dietzenbach-Germany) were measured. RESULTS: Thirty-two cases (Age, 6.3±3.4 years) and 30 controls were enrolled. Majority (69%) of cases had ALL. All patients had febrile neutropenia, except two. ELISA-IgM-HSV-1/2 was not positive in any case or control. ELISA-IgG-HSV-1/2 was positive in 11 (34%) cases and nine (30%) controls (p=1.0). Qualitative PCR for HSV-1 detected the virus in eight (25%) cases and nil controls (p=0.009). HSV-2 was not detected in any case/control by qualitative PCR. Quantitative PCR detected HSV-1 in 21 (66%) and HSV-2 in 22 (69%) cases. In controls, quantitative PCR detected HSV-1 in three (10%) and HSV-2 in none. In patients, the mean viral load of HSV-1 (5,500±15,987×10(4) copies/nanogram DNA) was more than HSV-2 (4.03±8.5×10(4)) (p=0.11). There was no correlation of HSV-1/2 with grading of mucositis. CONCLUSIONS: Both HSV-1/2 are commonly shed from oral mucosal lesions in children receiving chemotherapy. In a novel finding, real-time PCR detected copies of HSV-2 in 69% cases, all missed by conventional PCR. Implication for morbidity, if any, or treatment needs to be determined.


Assuntos
Herpes Simples/virologia , Herpesvirus Humano 1/isolamento & purificação , Herpesvirus Humano 2/isolamento & purificação , Neoplasias/tratamento farmacológico , Neoplasias/virologia , Estomatite/virologia , Anticorpos Antivirais/análise , Estudos de Casos e Controles , Criança , DNA Viral/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 2/genética , Herpesvirus Humano 2/imunologia , Humanos , Masculino , Mucosa Bucal/virologia , Reação em Cadeia da Polimerase em Tempo Real , Eliminação de Partículas Virais
16.
J Biol Chem ; 288(52): 37048-56, 2013 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-24202179

RESUMO

The renin-angiotensin system plays an important role in the regulation of blood pressure via angiotensin II and the angiotensin II receptor type 1 (AT1R). Human AT1R gene promoter has four SNPs: T/A at -777, T/G at -680, A/C at -214, and A/G at -119, that are in linkage disequilibrium. Variants -777T, -680T, -214A, and -119A almost always occur together (named haplotype I), and variants -777A, -680G, -214C, and -119G almost always occur together (named haplotype II) in Caucasian subjects. Genomic DNA analyses, from 388 normotensive and 374 hypertensive subjects, link haplotype I of the human AT1R (hAT1R) gene with hypertension in Caucasians (p = 0.004, χ(2) = 8.46). Our results show increased basal promoter activity of the hAT1R gene in cells (H295R and A7r5) transfected with reporter construct containing haplotype I. We also show increased binding of the transcription factor, USF2, to oligonucleotide containing nucleoside -214A as opposed to -214C. Recombineering of a 166-kb bacterial artificial chromosome containing 68 kb of the 5'-flanking region, 45 kb of the coding sequence, and 53 kb of the 3'-flanking region of the hAT1R gene was employed to generate transgenic mice with either haplotype. We show that (a) hAT1R mRNA level is increased in the kidney and heart of transgenic mice containing haplotype I as compared with haplotype II; (b) USF2 binds more strongly to the chromatin obtained from the kidney of transgenic mice containing haplotype I as compared with haplotype II; and (c) blood pressure and oxidative stress are increased in transgenic mice containing haplotype I as compared with haplotype II.


Assuntos
Haplótipos , Hipertensão , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Receptor Tipo 1 de Angiotensina , Idoso , Animais , Pressão Sanguínea/genética , Cromossomos Artificiais Bacterianos/genética , Feminino , Humanos , Hipertensão/genética , Hipertensão/metabolismo , Rim/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Miocárdio/metabolismo , Estresse Oxidativo/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor Tipo 1 de Angiotensina/biossíntese , Receptor Tipo 1 de Angiotensina/genética , Fatores Estimuladores Upstream/genética , Fatores Estimuladores Upstream/metabolismo , População Branca
17.
Pediatr Rheumatol Online J ; 10(1): 24, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22901283

RESUMO

BACKGROUND: Paediatric systemic lupus erythematosus (pSLE) exhibits an aggressive clinical phenotype with severe complications and overall poor prognosis. The aim of this study was to analyse differential expression of low molecular weight (LMW) serum protein molecules of pSLE patients with active disease in comparison to sera of healthy age matched controls. Further, some of the differential expressed spots were characterised and identified by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS) and liquid chromatography (LC-MS). METHODS: 2D-PAGE was performed using pooled sera of active pSLE and age matched healthy controls. Gels were silver-stained and differentially expressed protein spots were detected by automated image master platinum 2D software. 79 ± 17 protein spots were detected for control gels and 78 ± 17 protein spots for patient gels. Of these eleven protein spots were selected randomly and characterized by MALDI-TOF MS (five protein spots) and LC MS (six protein spots) techniques. RESULTS: Out of the 11 protein spots, 5 protein spots were significantly upregulated viz., leiomodin 2 (LMOD2); epidermal cytokeratin 2; immunoglobulin kappa light chain variable region; keratin 1 and transthyretin (TTR). Three protein spots were significantly down regulated e.g., apolipoprotein A1 (APOA1); chain B human complement component C3c; campath antibody antigen complex. Two protein spots (complement component C3; retinol binding protein (RBP) were found to be expressed only in disease and one protein spot cyclohydrolase 2 was only expressed in controls. CONCLUSIONS: We conclude that 2-D maps of patients with active pSLE and controls differ significantly. In this pilot study, using proteomic approach we have identified differential expressed proteins (of LMW) e.g., RBP, LMOD 2, TTR, Component C3c Chain B and APO A1. However, in future, further studies need to confirm the physiological and pathological role of these proteins in similar cohorts of pSLE.

18.
J Environ Biol ; 30(2): 271-3, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20121030

RESUMO

Local environment (temperature and relative humidity) affects reproductive biology in Pyrostegia venusta (Bignoniaceae) growing at Agra and Mysore. At Agra, the species flowers profusely during December to March, but fails to bear fruits. At Mysore, on the other hand it flowers during November to February and produces well developed fruits with winged seeds. This species, growing at two places, exhibited differences in their pollen fertility and in vivo pollen germination. Pollen fertility at Agra and Mysore was 27.55 and 80-90%, respectively The in vivo pollen germination on stigmatic surface was only 3-4% at Agra, but 85-95% at Mysore. The flowers at Agra also exhibited heterostyly and increased number of stamens and stigmatic lobes. The significantly low and wide ranged temperature (4.5-33.8 degrees C) and between 23-98% RH during the flowering period at Agra could be the cause for reduced in pollen fertility floral polymorphism and inhibition of pollen germination on the stigmatic surface and fruitlessness. At Mysore, where temperature ranges between 20.2-33.5 degrees C and RH varies from 33-75% profuse fruiting takes place. The study shows a direct control of environment over the process of reproduction.


Assuntos
Bignoniaceae/fisiologia , Ecossistema , Animais , Germinação
19.
Contraception ; 76(4): 297-305, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17900441

RESUMO

BACKGROUND: The aim of this study was to compare in vitro the role of two oral contraceptives, desogestrel (a less androgenic derivative of levonorgestrel) and levonorgestrel--alone and in combination with ethinyl estradiol--on low-density lipoprotein (LDL) receptor regulation by assessing receptor protein expression and functional effectiveness. STUDY DESIGN: Placental tissue and cultured placental cells (JEG-3) were used to study the expression and endocytotic activity of LDL receptor protein. The expression of the receptor was assessed by immunocytochemistry and immunoblot assays with and without contraceptive challenge. Functioning activity of LDL receptor was studied by measuring the rate of uptake of LDL by placental cells. Quantification of LDL was based on the total cholesterol content of the lipoprotein. RESULTS: A combination of desogestrel (20 ng/mL of incubation medium) and ethinyl estradiol (10 ng/mL of incubation medium) maintained the LDL receptor at high level of expression and functioning mode. In contrast, the double-blind preparation of levonorgestrel (20 ng/mL) and ethinyl estradiol (10 ng/mL) had shown much lower expression as well as receptor-mediated LDL uptake. The concentration of contraceptives used in this study was similar to the prevailing concentration of oral contraceptives in clinical use. CONCLUSION: Higher expression of LDL receptor and enhanced rate of LDL uptake by the receptor protein projects the possibility that there might be less atherosclerosis-related disorders from the combination of desogestrol and ethinyl estradiol.


Assuntos
Anticoncepcionais Orais Combinados/farmacologia , Desogestrel/farmacologia , Etinilestradiol/farmacologia , Levanogestrel/farmacologia , Placenta , Receptores de LDL/efeitos dos fármacos , Linhagem Celular Tumoral , LDL-Colesterol/metabolismo , Humanos , Placenta/citologia , Placenta/efeitos dos fármacos , Receptores de LDL/metabolismo , Regulação para Cima
20.
J Environ Biol ; 25(3): 291-7, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15847337

RESUMO

Cassia siamea plants growing at two different sites (polluted and non-polluted) on two important roads of Agra city exhibited significant differences in their flowering phenology and floral morphology. The flowering in plants growing at polluted site is delayed and there was a marked reduction in flowering density, flowering period, size of floral parts, pollen fertility, fruit and seed-set. SEM observations revealed the presence of well developed glandular structures and reduction in the number and size of large stomata on the anther surface at polluted site. These changes were found to be closely associated with the extent of air pollution caused mainly by significant in the number of automobiles.


Assuntos
Poluentes Atmosféricos/toxicidade , Cassia , Flores/efeitos dos fármacos , Constituição Corporal/efeitos dos fármacos , Constituição Corporal/fisiologia , Fertilidade/efeitos dos fármacos , Fertilidade/fisiologia , Flores/anatomia & histologia , Frutas/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Pólen/efeitos dos fármacos , Pólen/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Emissões de Veículos/toxicidade
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