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1.
Pharmacogn Mag ; 11(41): 163-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25709228

RESUMO

BACKGROUND: In the last decade, a growing interest particularly in determining the cardiovascular effects of herbal extracts took place among researchers. OBJECTIVE: Herein, we aimed to investigate the microvascular and blood pressure lowering effects of two differently processed extracts of the same herb, Alchemilla vulgaris (Rosaceaea), which was revealed to contain high levels of vasoactive compounds. MATERIALS AND METHODS: For the purpose, endothelium intact rat mesenteric arteries were mounted in a myograph system and contracted with prostaglandin F2α (PGF2α: 3 × 10(-5) M) or potassium chloride (K(+): 40 mM). Then, aqueous and methanol extracts were added at 0.01-10 mg/ml concentrations in a cumulative manner. RESULTS: Both extracts produced relaxations in PGF2α (3 × 10(-5) M) precontracted arteries which were insensitive to the inhibitors of endothelium derived vasoactive substances namely, L(G)-nitro-L-arginine (10(-4) M), ODQ (10(-5) M) and indomethacin (10(-5) M) or removal of endothelium. Opposite vascular effects were observed when extracts were applied in K(+) precontracted arteries. In addition, oral administration of the methanol extract of Alchemilla vulgaris, but not the aqueous extract, reduced blood pressure significantly in L-NAME hypertensive rats. CONCLUSION: Our results demonstrated that the methanol extract of Alchemilla vulgaris has more prominent and favourable vascular effects in normal and experimental hypertensive conditions reinforcing its traditional use in cardiovascular disorders, in particular hypertension. These results most likely give rise to further studies to reveal its mechanism of action and clinical value of this herb.

2.
J Physiol Pharmacol ; 64(1): 11-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23568966

RESUMO

Tight junctions are the most apically positioned intercellular junction and play many roles such as securing adjacent cells, forming barriers from extracellular materials, and facilitating paracellular transport. Occludin and junction adhesion molecule A (JAM-A) are classified as transmembrane proteins that are directly involved in paracellular transport. Zona occludens-1 (ZO-1) is a protein that contains a PDZ domain which forms a binding site for other tight junction proteins. In this study, we assessed the differential expression of these tight junction components in various mouse organs including the intestine (duodenum, ileum, and colon), kidney, liver, lung, brain, and skeletal muscle. Realtime PCR and Western blot assays were performed to measure the gene and protein expression of occludin, JAM-A, and ZO-1. Similar levels of occludin gene expression were detected in all tissues except for skeletal muscle in which occludin expression was not found. The JAM-A and ZO-1 genes were highly expressed in all the tested tissues. Localization of occludin, JAM-A, and ZO-1 was determined by immunohistochemistry. These proteins were detected in the intercellular apical junctions in each tissue except for occludin (which was not observed in skeletal muscle). These immunostaining data were consistent with the gene expression profiles we obtained. Our results suggest that occludin, JAM-A, and ZO-1 genes are normally expressed in the intestine, kidney, liver, lung, and brain indicating that these factors may be essential for maintaining appropriate physiological concentration of ions, solutes and water.


Assuntos
Moléculas de Adesão Celular/biossíntese , Ocludina/biossíntese , Receptores de Superfície Celular/biossíntese , Proteína da Zônula de Oclusão-1/biossíntese , Animais , Moléculas de Adesão Celular/genética , Expressão Gênica , Masculino , Camundongos , Ocludina/genética , Receptores de Superfície Celular/genética , Junções Íntimas/genética , Junções Íntimas/metabolismo , Distribuição Tecidual , Transcriptoma , Proteína da Zônula de Oclusão-1/genética
3.
J Physiol Pharmacol ; 63(5): 445-55, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23211298

RESUMO

There are concerns about the combined estrogenic effects of chemicals since mixtures of these chemicals exist in our environment. This study investigated potential additional interactions between bisphenol A (BPA) and isobutylparaben (IBP), which are major xenoestrogens used in the manufacture of plastics, cosmetics, drugs, and other products. The combined effects of these two chemicals were analyzed by measuring the expression of calbindin-D(9k) (CaBP-9k) in rat pituitary cancer GH3 cells. GH3 cells were treated with single and combination doses of both chemicals (BPA single doses: 10(-7), 10(-6) and 10(-5) M; IBP single doses: 10(-7), 10(-6) and 10(-5) M, and each of the BPA and IBP doses combined). Prior to treatment, cells were temporarily transfected with a plasmid containing an ERE-luciferase reporter gene. Luciferase activity was measured as an indicator of ER activation by 17ß-estradiol (E2), BPA, and IBP. BPA (10(-5) M) combined with IBP (10(-7) M and 10(-6) M) induced a significant increase in the luciferase activity. Twenty-four hours after treatment, dose-dependent effects were observed in both single and combined dose groups, and several combination doses induced significant increases in the expression of CaBP-9k and progesterone receptor (PR) at both transcriptional and translational levels. Pre-treatment with ICI 182,780, a pure estrogen antagonist, significantly reversed BPA- and IBP-induced CaBP-9k and PR upregulation in GH3 cells. Taken together, these results indicate that BPA and IBP may have additionally increased estrogenic potency via an estrogen receptor-mediated pathway.


Assuntos
Compostos Benzidrílicos/farmacologia , Disruptores Endócrinos/farmacologia , Estrogênios não Esteroides/farmacologia , Parabenos/farmacologia , Fenóis/farmacologia , Receptores de Progesterona/metabolismo , Proteína G de Ligação ao Cálcio S100/metabolismo , Animais , Calbindinas , Linhagem Celular , Hipófise/citologia , RNA Mensageiro/metabolismo , Ratos , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/genética , Elementos de Resposta , Proteína G de Ligação ao Cálcio S100/genética
4.
Hum Exp Toxicol ; 31(2): 134-44, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22027501

RESUMO

Although the endocrine-disrupting bioactivity of parabens is weakly estrogenic (parabens are xenoestrogens), their combined synergistic effect is unknown. The aim of this study was to investigate the effects of methyl paraben (MP), ethyl paraben (EP), propyl paraben (PP), isopropyl paraben (IPP), butyl paraben (BP), and isobutyl paraben (IBP), either alone or in combination (MP + EP + PP + BP; PP + IPP; and BP + IBP) on the induction of the estrogenic biomarker gene, calbindin-D(9k) (CaBP-9k), in rat pituitary lactosomatotrophic GH3 cells. The expression of CaBP-9k mRNA and protein was analyzed using real-time PCR and Western blot analysis, respectively. After 24 h of treatment, a significant increase in CaBP-9k expression was observed. This was dependent upon the length of the paraben alkyl chains (shortest in MP and longest in IBP). Interestingly, the synergistic effects of these paraben combinations were observed at a dose (10(-5) M) of these parabens, which induced the highest expression of CaBP-9k mRNA and protein. To investigate the involvement of estrogen receptors (ERs) and progesterone receptors (PRs), through which parabens exert their effects, the expression levels of ERα and PR-B were also examined. The expression of ERα mRNA and protein fluctuated after paraben treatment in GH3 cells, which was not significant. However, the expression level of ERα gene was induced when cotreated with 17ß-estradiol (E2) and ICI 182, 780 (estrogen receptor antagonist). The different combinations of parabens induced the expression of the PR-B gene, which was abolished by cotreatment with ICI 182,780. The expression patterns of CaBP-9k and PR-B genes appeared to be similar in response to paraben treatments. This implied that CaBP-9k expression in GH3 cells may be induced by parabens via a PR-mediated pathway. Taken together, these results suggest that exposure to multiple parabens at low concentrations may increase their synergistic estrogenic activities in GH3 cells through a PR-mediated pathway.


Assuntos
Anti-Infecciosos/farmacologia , Estrogênios/farmacologia , Parabenos/farmacologia , Conservantes Farmacêuticos/farmacologia , Proteína G de Ligação ao Cálcio S100/genética , Animais , Calbindinas , Linhagem Celular , Sinergismo Farmacológico , Estradiol/análogos & derivados , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Fulvestranto , Expressão Gênica/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Proteína G de Ligação ao Cálcio S100/metabolismo
5.
J Physiol Pharmacol ; 62(5): 499-504, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22204796

RESUMO

Maintenance of calcium (Ca) balance in the uterus is critically important for many physiological functions, including smooth muscle contraction during embryo implantation. Ca transport genes, i.e., transient receptor potential cation channel subfamily V members 5/6 (TRPV5/6), calbindins, plasma membrane Ca(2+)-ATPase 1 (PMCA1), and NCX1/NCKX3, may play roles in the uterus for Ca transport and reproductive function. Although these Ca transport genes may have a role in Ca metabolism, their role(s) and molecular mechanisms require further elucidation. In this review, we highlight the expression and regulation of Ca transport genes in the uterus to clarify their potential role(s). Since Ca transport genes are abundantly expressed in reproductive tissues in a distinct manner, they may be involved in specific uterine functions including fetal implantation, Ca homeostasis, and endometrial cell production.


Assuntos
Cálcio/metabolismo , Endométrio/metabolismo , Regulação da Expressão Gênica , Calbindinas , Implantação do Embrião/genética , Implantação do Embrião/fisiologia , Feminino , Humanos , Ciclo Menstrual/genética , Ciclo Menstrual/metabolismo , Ciclo Menstrual/fisiologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Proteína G de Ligação ao Cálcio S100/genética , Trocador de Sódio e Cálcio/genética , Canais de Cátion TRPV/genética
6.
Prev Vet Med ; 41(2-3): 151-69, 1999 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-10448943

RESUMO

We conducted a cross-sectional study at two sites in the Philippines to obtain baseline information about weight-for-age of smallholder growing pigs, and to identify important constraints and opportunities for smallholder pig raisers. Using an interview-based questionnaire, we collected data about 115 (with 244 growing pigs) and 123 (212) herds at the northern and southern study sites, respectively. At these sites, the median weight-for-age was 5.7 and 5.5 kg/mo, respectively. There was herd-level clustering with respect to weight-for-age, and the breed and origin of the growing pig was strongly associated with this measure of productivity. Herd-level weight-for-age was higher for smallholders who had a strong production focus and who specialised in raising growing pigs.


Assuntos
Criação de Animais Domésticos , Suínos/crescimento & desenvolvimento , Fatores Etários , Animais , Peso Corporal , Estudos Transversais , Países em Desenvolvimento , Filipinas , Valores de Referência
7.
Prev Vet Med ; 41(2-3): 171-86, 1999 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-10448944

RESUMO

We conducted a cross-sectional study at two sites in the Philippines to obtain baseline information about the reproductive performance of smallholder sows, and to identify important constraints and opportunities for smallholder pig raisers. Using an interview-based questionnaire, we collected data about 99 (with 128 sows) and 123 (144) herds at the northern and southern study sites, respectively. A range of animal- and herd-level measures of sow productivity were assessed, including average interfarrowing interval (9.7 and 6.6 mo in herds at the northern and southern sites, respectively), number of liveborn piglets (8.5 and 8.4) and preweaning mortality (19.0% and 12.8%). We have identified a number of animal- and herd-level factors associated with the productivity of smallholder sows in the Philippines, including aspects of breeding and piglet management and nutrition.


Assuntos
Criação de Animais Domésticos , Fertilidade , Suínos/fisiologia , Animais , Estudos Transversais , Países em Desenvolvimento , Feminino , Filipinas , Valores de Referência
8.
Prev Vet Med ; 41(2-3): 187-94, 1999 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-10448945

RESUMO

Questionnaires are widely used in veterinary epidemiological studies. With careful design, assessment and administration, questionnaires can collect accurate data. In cross-cultural settings, questionnaire design is complicated by the added step of translation. As part of a cross-sectional study of smallholder pig raisers in the Philippines, we assessed the importance of translation as a source of error in our questionnaire. The questionnaire contained 120 questions that collected data for entry into 361 separate data-entry fields in a computerised database. The translation was verified using the methods of back-translation and pilot-testing to identify and quantify errors of literal translation, omission and mistranslation. Errors were identified in 44 (37%) questions that obtained data for 147 (41%) data-entry fields. Although errors might have remained in the final translated version of the questionnaire, we have no doubt that the verification procedures substantially improved the internal validity of the questionnaire. It is important that veterinary epidemiologists use such procedures to check the internal validity of translated questionnaires.


Assuntos
Criação de Animais Domésticos , Barreiras de Comunicação , Inquéritos e Questionários/normas , Medicina Veterinária , Animais , Características Culturais , Coleta de Dados/normas , Métodos Epidemiológicos , Idioma , Filipinas , Controle de Qualidade , Reprodutibilidade dos Testes , Suínos
10.
J Theor Biol ; 161(1): 1-12, 1993 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-8501923

RESUMO

A cellular automaton model describing immune system surveillance against cancer is furnished. In formulating the model, we have taken into account the microscopic mechanisms of cancerous growth, such as the proliferation of cancer cells, the cytotoxic behaviors of the immune system, the mechanical pressure inside the tumor and so forth. The model may describe the Gompertz growth of a cancer. The results are in agreement with experimental observations. The influences of the proliferation rate of cancer cells, the cytotoxic rate and other relevant factors affecting the Gompertz growth are studied.


Assuntos
Sistema Imunitário/imunologia , Modelos Biológicos , Neoplasias/patologia , Humanos , Imunidade Celular , Neoplasias/imunologia
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