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1.
BMJ Open ; 14(3): e071504, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38448060

RESUMO

OBJECTIVES: Self-medication with antibiotics (SMA) contributes significantly to the emergence of antimicrobial resistance (AMR), especially in low-income countries including Bangladesh. This study aimed to generate evidence on the self-reported prevalence of antibiotic self-medication and its determinants among indigenous people residing in Bangladesh's Chittagong Hill Tracts (CHT) districts. DESIGN: This study used a cross-sectional design with data collected through a survey using a semi-structured questionnaire. SETTING: This study was conducted from late January to early July 2021; among different indigenous group populations aged 18 years or more olders residing in the three districts of CHT. PARTICIPANTS: A total of 1336 indigenous people residing in Bangladesh's CHT districts were included. PRIMARY OUTCOME AND EXPLANATORY VARIABLES: The primary outcome measure was SMA while explanatory variables were socio-demographic characteristics, health status of participants, and knowledge of antibiotics usage and its side effects. RESULTS: Among the study participants, more males (60.54%) than females (51.57%) reported using antibiotics. The SMA rate was high among individuals with education levels below secondary (over 50%) and those in the low-income group (55.19%). The most common diseases reported were cough, cold and fever, with azithromycin being the most frequently used antibiotic. Levels of education, family income, having a chronic illness and place of residence were found to be the significant predictors of having good knowledge of antibiotic use as found in the ordered logit model. Findings from a logistic regression model revealed that men had 1.6 times higher odds (adjusted OR (AOR) 1.57; 95% CI 1.12 to 2.19) of SMA than women. Participants with ≥US$893 per month family income had lowest odds (AOR 0.14; 95% CI 0.03 to 0.64) of SMA than those who earned

Assuntos
Antibacterianos , Povos Indígenas , Humanos , Feminino , Masculino , Antibacterianos/uso terapêutico , Estudos Transversais , Bangladesh , Prevalência
2.
J Clin Invest ; 133(1)2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36301669

RESUMO

Signaling circuits crucial to systemic physiology are widespread, yet uncovering their molecular underpinnings remains a barrier to understanding the etiology of many metabolic disorders. Here, we identified a copper-linked signaling circuit activated by disruption of mitochondrial function in the murine liver or heart that resulted in atrophy of the spleen and thymus and caused a peripheral white blood cell deficiency. We demonstrated that the leukopenia was caused by α-fetoprotein, which required copper and the cell surface receptor CCR5 to promote white blood cell death. We further showed that α-fetoprotein expression was upregulated in several cell types upon inhibition of oxidative phosphorylation. Collectively, our data argue that α-fetoprotein may be secreted by bioenergetically stressed tissue to suppress the immune system, an effect that may explain the recurrent or chronic infections that are observed in a subset of mitochondrial diseases or in other disorders with secondary mitochondrial dysfunction.


Assuntos
Cobre , Doenças Mitocondriais , Camundongos , Animais , Cobre/metabolismo , alfa-Fetoproteínas/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Doenças Mitocondriais/metabolismo , Terapia de Imunossupressão
3.
Sci Total Environ ; 858(Pt 3): 159350, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36265620

RESUMO

Wastewater based epidemiology (WBE) is an important tool to fight against COVID-19 as it provides insights into the health status of the targeted population from a small single house to a large municipality in a cost-effective, rapid, and non-invasive way. The implementation of wastewater based surveillance (WBS) could reduce the burden on the public health system, management of pandemics, help to make informed decisions, and protect public health. In this study, a house with COVID-19 patients was targeted for monitoring the prevalence of SARS-CoV-2 genetic markers in wastewater samples (WS) with clinical specimens (CS) for a period of 30 days. RT-qPCR technique was employed to target nonstructural (ORF1ab) and structural-nucleocapsid (N) protein genes of SARS-CoV-2, according to a validated experimental protocol. Physiological, environmental, and biological parameters were also measured following the American Public Health Association (APHA) standard protocols. SARS-CoV-2 viral shedding in wastewater peaked when the highest number of COVID-19 cases were clinically diagnosed. Throughout the study period, 7450 to 23,000 gene copies/1000 mL were detected, where we identified 47 % (57/120) positive samples from WS and 35 % (128/360) from CS. When the COVID-19 patient number was the lowest (2), the highest CT value (39.4; i.e., lowest copy number) was identified from WS. On the other hand, when the COVID-19 patients were the highest (6), the lowest CT value (25.2 i.e., highest copy numbers) was obtained from WS. An advance signal of increased SARS-CoV-2 viral load from the COVID-19 patient was found in WS earlier than in the CS. Using customized primer sets in a traditional PCR approach, we confirmed that all SARS-CoV-2 variants identified in both CS and WS were Delta variants (B.1.617.2). To our knowledge, this is the first follow-up study to determine a temporal relationship between COVID-19 patients and their discharge of SARS-CoV-2 RNA genetic markers in wastewater from a single house including all family members for clinical sampling from a developing country (Bangladesh), where a proper sewage system is lacking. The salient findings of the study indicate that monitoring the genetic markers of the SARS-CoV-2 virus in wastewater could identify COVID-19 cases, which reduces the burden on the public health system during COVID-19 pandemics.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Seguimentos , Águas Residuárias , Marcadores Genéticos , RNA Viral
4.
Biomed Res Int ; 2022: 9092346, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937404

RESUMO

Body auscultation is a frequent clinical diagnostic procedure used to diagnose heart problems. The key advantage of this clinical method is that it provides a cheap and effective solution that enables medical professionals to interpret heart sounds for the diagnosis of cardiac diseases. Signal processing can quantify the distribution of amplitude and frequency content for diagnostic purposes. In this experiment, the use of signal processing and wavelet analysis in screening cardiac disorders provided enough evidence to distinguish between the heart sounds of a healthy and unhealthy heart. Real-time data was collected using an IoT device, and the noise was reduced using the REES52 sensor. It was found that mean frequency is sufficiently discriminatory to distinguish between a healthy and unhealthy heart, according to features derived from signal amplitude distribution in the time and frequency domain analysis. The results of the present study indicate the adequate discrimination between the characteristics of heart sounds for automatic detection of cardiac problems by signal processing from normal and abnormal heart sounds.


Assuntos
Cardiopatias , Ruídos Cardíacos , Algoritmos , Auscultação Cardíaca/métodos , Cardiopatias/diagnóstico , Humanos , Processamento de Sinais Assistido por Computador , Análise de Ondaletas
5.
Toxicol Rep ; 7: 183-187, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33384939

RESUMO

Medicinal plant as herbal medicine is widely used to cure infectious diseases. Rubus fruticosus L (R. fruticosus) has been studied for its antimicrobial and cytotoxic activities. Different polarity leave extracts were prepared by using hexane, chloroform, ethyl acetate and hydro alcoholic solvents. Agar diffusion method has been used to assess the antibacterial activity against two gram-positive Enterococcus faecalis and Staphylococcus aureus and two gram-negative Escherichia coli and Haemophilus influenza bacterial strains. Cytotoxic activity was carried out against brine shrimp using the nauplii method (BSL). The results so obtained for various experiments demonstrates the total number of extracts produces moderate to strong antibacterial activity against the gram (+ and -). The best activity was discovered within hydro alcoholic upon all concentrations, whereas the inhibition zone exists within the range of 6-11 mm. In addition to that, the cytotoxic activity test confirms that hydro alcoholic extracts the maximum toxicity for values LC50 (4.68-6.96 µg/ml), where the LC50 values for all extracts be located within the range of 4.68-6.96 µg/ml. Finally, the plant itself and its derived extracts have been used as a folk medicine to treat serious infectious diseases.

6.
Naunyn Schmiedebergs Arch Pharmacol ; 393(2): 191-201, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31485693

RESUMO

We previously reported the antifungal, antioxidant, and vasodilator effects of Ryudai gold (RD) and isolated some potentially active compounds. Here, we aimed to identify other active compounds present in RD and investigate their pharmacological effects, in terms of antioxidant, and inhibitory activities against skin disease-related enzymes, pancreatic α-amylase, and lipase enzymes. The methanol extract of RD rhizomes was subjected to repeated fractionation by silica gel column, Toyopearl HW-40F column, and high-performance liquid chromatography to obtain a pure compound. The isolated compound was characterized by analyzing its spectroscopic data, particularly nuclear magnetic resonance spectra. Inhibitory activities against α-amylase, pancreatic lipase, elastase, collagenase, xanthine oxidase, and tyrosinase were evaluated to investigate its potential antidiabetic, antiobesity, and enzyme inhibitory effects. Antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl-scavenging, reducing power, and 2-deoxyribose degradation assays. The purified compound was recognized as 4-methylene-8-hydroxybisabola-2,10-diene-9-one, a new compound. The content of this compound was 0.068 µmol/g or 0.016 mg/g of dry RG powder. Our results suggested that 4-methylene-8-hydroxybisabola-2,10-diene-9-one exhibited antidiabetic, antiobesity, enzyme inhibitory, and antioxidant activities by inhibiting their respective enzymes activity. 4-methylene-8-hydroxybisabola-2,10-diene-9-one could be a promising candidate therapeutic agent or a lead compound for the development of new synthetic drugs.


Assuntos
Fármacos Antiobesidade/farmacologia , Antioxidantes/farmacologia , Curcuma , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Animais , Fármacos Antiobesidade/química , Antioxidantes/química , Compostos de Bifenilo/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/química , Hipoglicemiantes/química , Camundongos , Picratos/química , Extratos Vegetais/química , Rizoma
7.
Nutrients ; 11(6)2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31146458

RESUMO

Garlic (Allium sativum L.) contains prebiotic components, fructans, antibacterial compounds, and organosulfur compounds. The complex ingredients of garlic seem to impart a paradoxical result on the gut microbiome. In this study, we used a mouse model to clarify the effects of whole garlic on the gut microbiome. C57BL/6N male mice were fed with or without whole garlic in normal diet (ND) or in high-fat diet (HFD) for 12 weeks. Supplementation with whole garlic attenuated HFD-enhanced ratio of serum GPT/GOT (glutamic-pyruvic transaminase/glutamic-oxaloacetic transaminase), levels of T-Cho (total cholesterol) and LDLs (low-density lipoproteins), and index of homeostatic model assessment for insulin resistance (HOMA-IR), but had no significant effect in the levels of serum HDL-c (high density lipoprotein cholesterol), TG (total triacylglycerol), and glucose. Moreover, garlic supplementation meliorated the HFD-reduced ratio of villus height/crypt depth, cecum weight, and the concentration of cecal organic acids. Finally, gut microbiota characterization by high throughput 16S rRNA gene sequencing revealed that whole garlic supplementation increased the α-diversity of the gut microbiome, especially increasing the relative abundance of f_Lachnospiraceae and reducing the relative abundance of g_Prevotella. Taken together, our data demonstrated that whole garlic supplementation could meliorate the HFD-induced dyslipidemia and disturbance of gut microbiome.


Assuntos
Bactérias/crescimento & desenvolvimento , Disbiose , Dislipidemias/prevenção & controle , Alho , Microbioma Gastrointestinal , Intestinos/microbiologia , Lipídeos/sangue , Raízes de Plantas , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bactérias/genética , Biomarcadores/sangue , Glicemia/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Dislipidemias/sangue , Dislipidemias/etiologia , Interações Hospedeiro-Patógeno , Intestinos/patologia , Masculino , Camundongos Endogâmicos C57BL
8.
Hum Mol Genet ; 26(23): 4617-4628, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28973536

RESUMO

SCO1 is a ubiquitously expressed, mitochondrial protein with essential roles in cytochrome c oxidase (COX) assembly and the regulation of copper homeostasis. SCO1 patients present with severe forms of early onset disease, and ultimately succumb from liver, heart or brain failure. However, the inherent susceptibility of these tissues to SCO1 mutations and the clinical heterogeneity observed across SCO1 pedigrees remain poorly understood phenomena. To further address this issue, we generated Sco1hrt/hrt and Sco1stm/stm mice in which Sco1 was specifically deleted in heart and striated muscle, respectively. Lethality was observed in both models due to a combined COX and copper deficiency that resulted in a dilated cardiomyopathy. Left ventricular dilation and loss of heart function was preceded by a temporal decrease in COX activity and copper levels in the longer-lived Sco1stm/stm mice. Interestingly, the reduction in copper content of Sco1stm/stm cardiomyocytes was due to the mislocalisation of CTR1, the high affinity transporter that imports copper into the cell. CTR1 was similarly mislocalized to the cytosol in the heart of knockin mice carrying a homozygous G115S substitution in Sco1, which in humans causes a hypertrophic cardiomyopathy. Our current findings in the heart are in marked contrast to our prior observations in the liver, where Sco1 deletion results in a near complete absence of CTR1 protein. These data collectively argue that mutations perturbing SCO1 function have tissue-specific consequences for the machinery that ultimately governs copper homeostasis, and further establish the importance of aberrant mitochondrial signaling to the etiology of copper handling disorders.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Cobre/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Mitocôndrias Cardíacas/metabolismo , Miocárdio/metabolismo , Animais , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/metabolismo , Membrana Celular/metabolismo , Cobre/deficiência , Transportador de Cobre 1 , Modelos Animais de Doenças , Complexo IV da Cadeia de Transporte de Elétrons/genética , Homeostase , Transporte de Íons , Metalochaperonas/genética , Metalochaperonas/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Chaperonas Moleculares , Miócitos Cardíacos/metabolismo , Oxirredução , Transdução de Sinais
9.
Cell Rep ; 10(6): 933-943, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25683716

RESUMO

Human SCO1 fulfills essential roles in cytochrome c oxidase (COX) assembly and the regulation of copper (Cu) homeostasis, yet it remains unclear why pathogenic mutations in this gene cause such clinically heterogeneous forms of disease. Here, we establish a Sco1 mouse model of human disease and show that ablation of Sco1 expression in the liver is lethal owing to severe COX and Cu deficiencies. We further demonstrate that the Cu deficiency is explained by a functional connection between SCO1 and CTR1, the high-affinity transporter that imports Cu into the cell. CTR1 is rapidly degraded in the absence of SCO1 protein, and we show that its levels are restored in Sco1-/- mouse embryonic fibroblasts upon inhibition of the proteasome. These data suggest that mitochondrial signaling through SCO1 provides a post-translational mechanism to regulate CTR1-dependent Cu import into the cell, and they further underpin the importance of mitochondria in cellular Cu homeostasis.

10.
Comput Biol Chem ; 52: 66-72, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25254941

RESUMO

BACKGROUND: Bacillus anthracis is a gram positive, spore forming, rod shaped bacteria which is the etiologic agent of anthrax - cutaneous, pulmonary and gastrointestinal. A recent outbreak of anthrax in a tropical region uncovered natural and in vitro resistance against penicillin, ciprofloxacin, quinolone due to over exposure of the pathogen to these antibiotics. This fact combined with the ongoing threat of using B. anthracis as a biological weapon proves that the identification of new therapeutic targets is urgently needed. METHODS: In this computational approach various databases and online based servers were used to detect essential proteins of B. anthracis A0248. Protein sequences of B. anthracis A0248 strain were retrieved from the NCBI database which was then run in CD-hit suite for clustering. NCBI BlastP against the human proteome and similarity search against DEG were done to find out essential human non-homologous proteins. Proteins involved in unique pathways were analyzed using KEGG genome database and PSORTb, CELLO v.2.5, ngLOC - these three tools were used to deduce putative cell surface proteins. RESULTS: Successive analysis revealed 116 proteins to be essential human non-homologs among which 17 were involved in unique metabolic pathways and 28 were predicted as membrane associated proteins. Both types of proteins can be exploited as they are unlikely to have homologous counterparts in the human host. CONCLUSION: Being human non-homologous, these proteins can be targeted for potential therapeutic drug development in future. Targets on unique metabolic and membrane-bound proteins can block cell wall synthesis, bacterial replication and signal transduction respectively.


Assuntos
Antibacterianos , Bacillus anthracis/genética , Proteínas de Bactérias/genética , Descoberta de Drogas , Genoma Bacteriano , Proteínas de Bactérias/química , Simulação por Computador , Bases de Dados de Proteínas , Humanos , Redes e Vias Metabólicas , Proteoma , Homologia de Sequência
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-672872

RESUMO

Objective: To analyze and identify the chemical compositions of different organic plants crude extracts of Mentha piperita (M. piperita) grown in Sultanate of Oman by gas chromatography-mass spectrometry (GC-MS). Methods: The powder sample was extracted with methanol by using Soxhlet extractor. Methanol crude extracts of M. piperita and its derived fractions of hexane, chloroform, ethyl acetate and butanol were prepared.Results:MS showed that majority of these compounds are bioactive.Conclusions:According to the results of the present study, the plant crude extracts could be Qualitative analyses of various organic plant crude extracts of M. piperita by using GC-used as medicine for the treatment of different diseases. The analysis and identification of the chemical compounds in the plant crude extracts by using GC-MS was the first time.

12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-672650

RESUMO

Objective: To isolate and analyse the chemical composition in the essential oils and free radical scavenging activity of different crude extracts from the fresh and dry leaves of vegetable plants of Lactuca sativa L. (L. sativa). Methods: The essential oils and volatile chemical constituents were isolated from the fresh and dry leaves of L. sativa (lettuce) grown in Sultanate of Oman by hydro distillation method. The antioxidant activity of the crude extracts was carried out by well established free radical scavenging activity (DPPH) method. Results: About 20 chemical compounds of different concentration representing 83.07% and 79.88% respectively were isolated and identified by gas chromatography-mass spectroscopy in the essential oils isolated from the fresh and dry leaves as α-pinene (5.11% and 4.05%), γ-cymene (2.07% and 1.92%), thymol (11.55%and 10.73%), durenol (52.00% and 49.79%), α-terpinene (1.66% and 1.34%), thymol acetate (0.99%and 0.67%), caryophyllene (2.11% and 1.98%), spathulenol (3.09% and 2.98%), camphene (4.11% and 3.65%), limonene (1.28% and 1.11%) representing these major chemical compounds. However, some other minor chemical constituents were also isolated and identified from the essential oil of lettuce including β-pinene, α-terpinolene, linalool, 4-terpineol, α-terpineol, o-methylthymol, L-alloaromadendrene and viridiflorene. Conclusions: The chemical constituents in the essential oils from the locally grown lettuce were identified in the following classes or groups of chemical compounds such as monoterpenes, sesquiterpenes volatile organic compounds and their oxygenated hydrocarbons. Therefore, the essential oils and the crude extracts from Omani vegetable species of lettuce are active candidates which would be used as antioxidant, antifungal or antimicrobial agents in new drugs preparation for therapy of infectious diseases.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-672628

RESUMO

Objective: To prepare various crude extracts using different polarities of solvent and to quantitatively evaluate their total phenol, flavonoids contents and phytochemical screening of Thymus vulgaris collected from Al Jabal Al Akhdar, Nizwa, Sultanate of Oman. Methods:The leave sample was extracted with methanol and evaporated. Then it was defatted with water and extracted with different polarities organic solvents with increasing polarities. The prepare hexane, chloroform, ethyl acetate, butanol and methanol crude extracts were used for their evaluation of total phenol, flavonoids contents and phytochemical screening study. The established conventional methods were used for quantitative determination of total phenol, flavonoids contents and phytochemical screening. Results: Phytochemical screening for various crude extracts were tested and shown positive result for flavonoids, saponins and steroids compounds. The result for total phenol content was the highest in butanol and the lowest in methanol crude extract whereas the total flavonoids contents was the highest in methanol and the lowest hexane crude extract. Conclusions:The crude extracts from locally grown Thymus vulgaris showed high concentration of flavonoids and it could be used as antibiotics for different curable and uncurable diseases.

14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-672529

RESUMO

Objective: To isolate and analyze the chemical composition in different crude extracts of from the leaves of locally grown of Thymus vulgaris L (T. vulgaris) by gas chromatography-mass spectrometry (GC-MS). Methods: The shade dried leaves powder was extracted with methanol by using Soxhlet extractor. Methanol crude extracts of T. vulgaris and the derived fractions of hexane, chloroform, ethyl acetate and butanol were obtained. Results: Qualitative analyses of various organic crude extracts of T. vulgaris by using GC-MS showed that there were different types of high and low molecular weight compounds. Most of the isolated and identified compounds by GC-MS in the crude extracts are basically biologically important. Further, the T. vulgaris leaf possessed certain characteristics that can be ascribed to cultivation on a domestic plantation. The crude extracts were prepared from the powder leaves of T. vulgaris for respective compounds can be chosen on the basis of above GC-MS analysis. Conclusions: All the major compounds were identified and characterized by spectroscopic method in different organic crude extracts of T. vulgaris are biologically active molecules. Thus the identification of a good number of compounds in various crude extracts of T. vulgaris might have some ecological role.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-672491

RESUMO

Objective: The aim of this present study was to isolate and analyze the chemical composition of essential oils from two different imported brands of Syzigium caryophyllatum (clove) samples using gas chromatography-mass spectrometry (GC-MS). Methods: The two essential oils were isolated by hydrodistillation from two different brands of Syzigium caryophyllatum (clove) such as Guzal and Shahi clove samples using Clevenger type apparatus. Results: Eleven chemical components were identified in the essential oil isolated from Guzal clove imported from Indonesia. The isolated components representing 99.03% of the Guzal clove oil were identified as eugenol (51.51%), caryophyllene (36.20%), α- caryophyllene (4.26%), acetyleugenol (2.64%), carvacrol (2.42%), α-cubebene (0.77%) and thymol (0.42%) were the major components with some other minor components isolated from the same. About twenty two components representing 99.73% were identified within the essential oil isolated from the Shahi brand clove which was imported from India with the main components being eugenol (46.53%), caryophyllene (43.03%),α-caryophyllene (4.61%), aceteugenol (2.54%), copaene (0.80%), α-farnesene (0.72%), germacrene (0.43%) and δ-cadinene (0.27%). Conclusions: Both the isolated essential oils were found to be rich in eugenol and caryophyllene. The clove essential oil from Guzal and Shahi was found to be comparable in terms of its eugenol and caryophyllene contents. According to the above findings, it is suggested that both brands of clove are of similar quality.

16.
Endocrinology ; 149(12): 6356-65, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18755799

RESUMO

Prenatal manipulations to the hypothalamic-pituitary-adrenal axis are shown to affect auditory responses to an acoustic challenge as well as behavior in adult life. To achieve these results, we examined the effect of prenatal dexamethasone (DEX) treatment in male and female adult rat offspring by assessing body and adrenal weight, anxiety using the elevated plus maze (EPM), and acoustic startle responses as well as the effects of acoustic challenge in the paraventricular nucleus (PVN). DEX male offspring had reduced adrenal gland weight in adult life and demonstrated anxiolytic-like behavior when tested on the EPM. The acoustic startle amplitude in naive DEX-treated male offspring was significantly higher compared with saline (SAL)-treated males and females and DEX-treated females. When challenged with either a glucocorticoid agonist or antagonist, the startle response of the SAL-treated males and females significantly increased or decreased in the presence of agonist and antagonist treatment, respectively, whereas DEX males and females were not affected. Acoustic challenge caused an increase in c-fos mRNA and glucocorticoid receptor nuclear translocation in the PVN of all groups. BDNF and TrkB mRNA increased in the PVN after acoustic challenge in the SAL-treated males and females but not in the DEX males or females. These findings exemplify the differential sensitivity of the developing nervous and endocrine systems to prenatal hormonal stress and demonstrate that prenatal DEX treatment elicits long-term behavioral alterations related to anxiety and auditory processing.


Assuntos
Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/genética , Dexametasona/toxicidade , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/genética , Regiões Promotoras Genéticas/genética , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Dexametasona/administração & dosagem , Éxons/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Glucocorticoides/administração & dosagem , Glucocorticoides/toxicidade , Imuno-Histoquímica , Hibridização In Situ , Núcleo Hipotalâmico Paraventricular/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Proteínas Proto-Oncogênicas c-fos/genética , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/análise
17.
Eur J Neurosci ; 17(10): 2035-41, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12786969

RESUMO

Prenatal exposure to excessive glucocorticoids alters the programming of the metabolic and endocrine balance of various organs, including the nervous system. In the present study, prenatal glucocorticoid treatment was shown to increase the susceptibility of the inner ear to acoustic noise trauma in adult life. Acute auditory brainstem response thresholds were not different between the age-matched groups. However, when measured at 48 h and 4 weeks postexposure, the dexamethasone (DEX)-treated rats showed little or no recovery from the trauma. In contrast, normal rats showed a significant amount of recovery by 48 h postexposure and continued to show further recovery over 4 weeks. In addition, acoustic trauma resulted in a massive outer hair cell loss in the DEX rats compared to minor loss in the normal rats. To determine whether oxidative stress plays a role in the recovery phase of acoustic trauma, the free radical scavenger PBN (100 mg/kg) was administered before, during and several times after noise exposure. PBN treatment significantly reduced the physiological and morphological cochlear differences which were observed between DEX and control rats after acoustic trauma. These data support the hypothesis that alterations in the intrauterine environment may modify the developmental programme of the cochlea, inducing dysfunction later in adult life. Excessive prenatal exposure to dexamethasone decreased the potential for recovery of the cochlea to oxidative stress induced by acoustic trauma; this decreased recovery potential can be counteracted by treatment with antioxidants.


Assuntos
Dexametasona/farmacologia , Glucocorticoides/farmacologia , Células Ciliadas Auditivas Externas/anormalidades , Perda Auditiva/patologia , Efeitos Tardios da Exposição Pré-Natal , Animais , Apoptose , Limiar Auditivo , Feminino , Sequestradores de Radicais Livres/metabolismo , Células Ciliadas Auditivas Externas/metabolismo , Células Ciliadas Auditivas Externas/patologia , Perda Auditiva/induzido quimicamente , Perda Auditiva/metabolismo , Ruído/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-Dawley
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