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1.
Fish Physiol Biochem ; 50(2): 589-603, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38175337

RESUMO

Although the immuno-modulatory and stress-relieving properties of ß-glucan is well elucidated in humans and other animal models, including fish, its role as a dietary supplement on reproduction is extremely scarce. Therefore, in this study, adult female fish were fed one of four test diets having 0 (control), 0.5, 1, and 1.5% ß-D-glucan for 130 days and its effect on reproductive performance, ovarian and liver histology, sex hormones, and transcript abundance of selected reproduction-related genes was assessed. Low dietary intake of ß-glucan improved fertilization and hatching rates (p<0.05). The relative fecundity and percentage of spawning females were higher (non-significant) in 0.5% ß-glucan-fed groups. Surprisingly, even after 130 days, spawning did not occur in 1.5% ß-glucan-fed individuals. Irrespective of ß-glucan intake, all the brooders recorded similar plasma 17ß-estradiol and maturation-inducing hormone (p>0.05). Higher intake of ß-glucan (1.5%) upregulated aromatase genes without a parallel increase in 17ß-estradiol. However, plasma vitellogenin increased with increasing ß-glucan up to 1.0% then declined at 1.5% (p<0.05). The fish that received control, 0.5, and 1.5% ß-glucan recorded similar vitellogenin levels in their plasma. Significantly higher plasma cortisol was evidenced in 1.5% ß-glucan fed brooders (p<0.05). Histologically, higher follicular atresia and leaking of yolk material was evidenced in 1.5% ß-glucan-fed group. Liver histology revealed the highest nutrient/lipid accumulation in fish that received 1.0% and 1.5% ß-glucan. This study demonstrated the stimulatory effect of ß-glucan intake at a lower dose (0.5%) on reproduction. However, higher intake (1.5%) could perturb normal reproductive function in a fish model and caused an increased number of atretic follicles leading to spawning/reproductive failure.


Assuntos
Cyprinidae , beta-Glucanas , Humanos , Feminino , Animais , Vitelogeninas , beta-Glucanas/farmacologia , Atresia Folicular , Reprodução , Estradiol
2.
J Therm Biol ; 102: 103120, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34863483

RESUMO

Nutritional programming signifies a process in which broodstock feeding approaches have long-term effects on the subsequent progeny. The present study aimed to elucidate whether supplementing golden mahseer, Tor putitora broodstock diets with ß-glucan affects progeny growth performance, survival, thermal tolerance, and non-specific immunity. Initially, the growth performance of progeny produced from brooders fed with different levels of ß-glucan was non-significant. However, on the 15th and 35th DPH, the maximum weight was observed in fry obtained from the brooders fed with 0.5% followed by 1.0% ß-glucan. Furthermore, on 50th DPH, significantly higher weight was registered in the fry from the 0.5% ß-glucan fed group while 1.0% ß-glucan group had no transgenerational effect on growth. The condition factor of fry obtained from golden mahseer brooders fed with a 0.5% ß-glucan diet was greater than the control and 1.0% ß-glucan fed group. On the other hand, we did not find any significant transgenerational influence of ß-glucan on the survival of the progeny. The thermal tolerance of fry produced from brooders fed with ß-glucan was significantly modulated at both end-points (CTmax and CTmin). Expression of interleukin-1ß was significantly up-regulated in fry obtained from ß-glucan fed brooders. In contrast, the expression level of tumor necrosis factor-α was significantly higher only in fry produced from 1.0% ß-glucan fed brooders. The expression of immunoglobulin light chain and serum amyloid A gene was significantly higher in fry produced from 0.5% ß-glucan fed brooders. Overall results suggest that the dietary provisioning of ß-glucan in golden mahseer brooders can be a strategy to produce healthy and robust fry in captivity for stock enhancement and conservation programs.


Assuntos
Cyprinidae/crescimento & desenvolvimento , Espécies em Perigo de Extinção , Termotolerância/efeitos dos fármacos , beta-Glucanas/farmacologia , Animais , Cyprinidae/imunologia , Cyprinidae/metabolismo , Suplementos Nutricionais , Feminino , Larva/efeitos dos fármacos , Masculino
3.
Eur Rev Med Pharmacol Sci ; 25(12): 4258-4273, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34227093

RESUMO

OBJECTIVE: Mutations and polymorphisms in genes of cell- cycle and apoptosis regulatory pathway influence the breast cancer risk. Analysis of single low penetrance mutant alleles may not reflect the precise risk association when analyzed alone. PATIENTS AND METHODS: A total of 115 DNA samples extracted from breast cancer patients and an equal number of age and sex-matched normal controls were used for polymorphic analysis. Genotyping for p21 rs1801270 and CCND1 rs603965 was done by PCR-RFLP method while AFLP method was used for p53 rs1042522 single nucleotide polymorphism detection. Statistical methods included simple mean±SD and correlation coefficient to analyze the risk of association of p21, p53 and CCND1 SNPs and breast cancer. RESULTS: Individuals harboring SNPs in p21, p53 and CCND1 genes namely rs1801270, rs1042522 and rs603965, respectively were rendered increasingly susceptible to developing breast cancer when compared with normal controls. CONCLUSIONS: Our report emphasizes the need of combinational analysis of low-penetrance mutant alleles to assess accurately their association with breast cancer risk. Future case-control studies analyzing gene-environment interactions across different populations may confirm reported risk associations of studied polymorphisms with developing breast cancer.


Assuntos
Ciclina D1/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Polimorfismo Genético/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade
4.
Fish Shellfish Immunol ; 118: 119-146, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34289423

RESUMO

The present study was undertaken to characterize and analyze the expression of non-specific immune genes to get an insight into the early immune status of endangered golden mahseer. In this study, the full-length mRNA sequence of IFNγ, TNFα, C3, and IL10 was 927, 1409, 5125 and 1177 bp with an ORF of 558, 765, 4938, and 540 bp, encoding a putative protein of 185, 254, 1645, and 179 amino acid residues, respectively. The deduced amino acid sequences of these genes shared highly conserved structures with those from other cyprinids. Ontogenic real-time qPCR results indicated that expression of IFNγ and TNFα was lower until the morula stage and increased from blastula stage and found maximum at the organogenesis stage. Expression of the C3 gene was lower until the gastrula stage, followed by a linear increase from organogenesis to the pre-metamorphosis stage. The expression of IL10 was significantly lower during early developmental stages (till gastrula stage) and reached maximum at organogenesis. The level of IL1ß was found maximum in unfertilized eggs and remained elevated till the morula stage. TLR4 expression remained lower during the initial developmental stages and reached the maximum at the organogenesis stage. The expression level of defensin1 was substantially low until the organogenesis stage. In comparison, hepcidin1 was found considerably high until the blastula stage and remained significantly lower during later stages of development. Overall, the data generated improves knowledge on the immune status of endangered golden mahseer during embryonic and larval development, which may help develop effective immunomodulatory interventions during nursery rearing of golden mahseer to produce fry with better fitness.


Assuntos
Cyprinidae , Fator de Necrose Tumoral alfa , Sequência de Aminoácidos , Animais , Cyprinidae/genética , Cyprinidae/imunologia , Interleucina-10 , RNA Mensageiro
5.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1698-1704, Sept.-Oct. 2020. tab
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1131578

RESUMO

The present study was carried out to evaluate the prevalence and hematological effects of Toxoplasma gondii in sheep and goat in district Dera Ghazi Khan. Blood samples (n=204) were collected comprise goats (n=101) and sheep (n=103) alongwith age, gender and breeds of animals. Samples were collected randomly from 25 flocks of 7 different union council Viz. Vehova, Tibbi Qaisrani, Lakhani, Kohar, Tuman Qaisrani, Nutkani and Kot Qaisrani of Tehsil Taunsa Sharif at least 4 animals from each flock. All ruminants divide into three groups based on age, breed and gender. The prevalence was detected through two different kits Viz. LAT and ELISA kit. The overall prevalence suspected in goats through LAT and ELISA kit was (35.64%), (32.67%) and in sheep was (25.24%), (23.30%) respectively. The Toxoplasma gondii had a significant effect on goats in age groups and non-significant all other groups of goats and sheep. Toxoplasma gondii had a significant effect on all hematological parameters like Hemoglobin, total leukocyte cells, granulocytes, lymphocytes, platelets, and red blood cells, except monocytes. In conclusion of the current study, toxoplasmosis is prevalent among ruminants, reveals the possibility of transmission to humans on the use of host animals as protein source.(AU)


O objetivo do presente estudo foi avaliar a prevalência e efeitos hematológicos de Toxoplasma gondii em ovelhas e cabras no distrito Dera Ghazi Khan. Amostras de sangue (n=204) foram coletadas para incluir cabras (n=101) e ovelhas (n=103), além de idade, gênero e raça dos animais. Amostras foram coletadas aleatoriamente de 25 rebanhos de 7 conselhos sindicais: Vehova, Tibbi Qaisrani, Lakhani, Kohar, Tuman Qaisrani, Nutkani e Kot Qaisrani of Tehsil Taunsa Sharif com pelo menos 4 animais em cada rebanho. Todos os ruminantes foram divididos em três grupos baseados em idade, raça e gênero. A prevalência foi detectada usando dois kits, LAT e ELISA. A prevalência total suspeita em cabras através dos kits LAT e ELISA foi (35.64%), (32.67%) e em ovelhas foi (25.24%), (23.30%) respectivamente. O Toxoplasma gondii teve efeito significativo em cabras em grupos de idade e não significativo em todos os outros grupos de cabras e ovelhas. Toxoplasma gondii teve efeito significativo em todos os parâmetros hematológicos como hemoglobina, células totais de leucócitos, granulócitos, linfócitos, plaquetas e glóbulos vermelhos, exceto monócitos. O presente estudo conclui que toxoplasmose é prevalente entre ruminantes, e revela a possibilidade de transmissão para humanos com o uso de animais hospedeiros como fonte de proteína.(AU)


Assuntos
Animais , Toxoplasma/isolamento & purificação , Cabras/parasitologia , Toxoplasmose Animal/epidemiologia , Paquistão , Ruminantes/parasitologia , Ensaio de Imunoadsorção Enzimática/veterinária , Estudos Soroepidemiológicos , Prevalência
6.
Plant Pathol J ; 32(5): 396-406, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27721689

RESUMO

Continuous supplementation of mineral nutrients and salicylic acid (SA) as foliar application could improve efficacy in controlling basal stem rot (BSR) disease in oil palm seedling. It is revealed from the results that the highest disease severity index (58.3%) was recorded in T8 treatments at 9 months after inoculation. The best disease control was achieved by T7 treatments (calcium/copper/SA [Ca/Cu/SA]) (5.0%) followed by T1 (5.5%), T5 (5.8%), T3 (8.3%), T6 (8.3%), T4 (13.3%), and T2 (15.8%) treatments. Continuous supplementation of Ca/Cu/SA was found to be the most effective in controlling the disease and the high performance liquid chromatography results showed the detection of ergosterol at very low concentration in the treated samples. Moreover, the transmission electron microscopy analysis results clearly indicated that T7 treatment was also enhancing lignification, which was responsible for the thickness of the secondary cell walls and middle lamella compared to untreated samples. It was therefore, concluded that continuous supplementation of minerals nutrients and SA could effectively suppress disease severity by reducing ergosterol activity and also improve the process of lignification in the treated plants. Furthermore, this treatment also managed to delay the onset of BSR symptoms and promote the growth of the seedlings and eventually suppress the BSR disease.

7.
J Anim Physiol Anim Nutr (Berl) ; 97(6): 1075-83, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23186225

RESUMO

Two experiments were conducted to elucidate the possible effects of dietary L-tryptophan (TRP) in Labeo rohita based on growth performance and physio-biochemical responses. In the experiment I, a 60-day feeding trial was carried out to elucidate the effects of dietary TRP enrichment on growth performance and physio-biochemical responses. In the experiment II, the TRP pre-fed L. rohita, from experiment I, was exposed to temperature and salinity stress to evaluate stress-mitigating efficacy of TRP. In L. rohita, dietary supplementation of TRP showed significant effect on weight gain percentage and feed conversion ratio but not on blood glucose. A significant increase in RNA content and RNA/DNA ratio upon TRP supplementation was observed and was positively correlated with growth performance. The results of experiment II indicated that weight gain percentage, serum T3 and T4 levels were significantly reduced in groups that were exposed to temperature and salinity stress and fed diets without TRP supplementation. However, dietary supplementation of TRP significantly augmented weight gain percentage in stress-exposed groups. Tryptophan supplementation helped in bringing back T3 and T4 levels comparable with control. A significant increase in superoxide dismutase, catalase, Adenosine triphosphatase, blood glucose and serum cortisol was observed in temperature- and salinity-exposed groups fed without TRP-supplemented diets. However, TRP supplementation was found to be effective in restoring the above parameters. The results of these experiments suggest that dietary TRP supplementation augments growth, lowers energy demand and helps in mitigating thermal and salinity stress in L. rohita.


Assuntos
Ração Animal/análise , Cyprinidae/fisiologia , Dieta/veterinária , Salinidade , Estresse Fisiológico/efeitos dos fármacos , Triptofano/farmacologia , Adenosina Trifosfatases/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Cloreto de Sódio/toxicidade , Superóxido Dismutase/metabolismo , Água/química
9.
J Perinatol ; 27(4): 241-3, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17377606

RESUMO

Treatment of maternal chronic myeloid leukemia with imatinib mesylate is avoided because of potential fetal effects. Two women with progression of disease during pregnancy required imatinib therapy. Concentrations of imatinib in maternal blood, placenta, umbilical cord blood and breast milk were 886, 2452, 0 to 157, and 596 ng/ml, respectively. Concentrations of the active metabolite CGP74588 in maternal blood, placenta, umbilical cord blood and breast milk were 338, 1462, 0 and 1513 ng/ml, respectively. As Imatinib and CGP74588 cross the mature placenta poorly, use of the drug after the first trimester may be reasonable under some circumstances. Imatinib and CGP74588 are found in breast milk, and therefore avoidance of breastfeeding is advisable.


Assuntos
Antineoplásicos/farmacocinética , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Piperazinas/farmacocinética , Complicações Neoplásicas na Gravidez/tratamento farmacológico , Pirimidinas/farmacocinética , Antineoplásicos/sangue , Benzamidas , Feminino , Sangue Fetal/metabolismo , Humanos , Mesilato de Imatinib , Leite Humano/metabolismo , Piperazinas/sangue , Piperazinas/metabolismo , Placenta/metabolismo , Gravidez , Pirimidinas/sangue , Pirimidinas/metabolismo
10.
Bone Marrow Transplant ; 29(4): 313-9, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11896428

RESUMO

Taurolidine has been shown to have remarkable cytotoxic activity against selected human tumor cells at concentrations that spare normal cells. In this study we have extended this observation and assessed the ability of Taurolidine to purge tumor cells from chimeric mixtures of bone marrow (BM) and neoplastic cells. Normal murine BM and human leukemic (HL-60) or ovarian (PA-1) tumor cell lines were used as models. Exposure of tumor cells to 2.5 mM Taurolidine for 1 h resulted in the complete elimination of viable cells. In contrast, exposure of BM to 5 mMTaurolidine for 1 h reduced CFU-GM, BFU-E and CFU-GEEM colony formation by only 23.0%, 19.6% and 25.2%, respectively. Inhibition of long-term BM culture (LTBMC) growth following a 1 h exposure to 5 mM Taurolidine also was approximately 20% compared to untreated LTBMC. Finally, chimeric cultures were generated from BM and HL-60GR or PA-1GR cells (tumor cells transfected with the geneticin resistance gene). Exposure of these chimeric cultures to 5 mM Taurolidine for 1 h totally eliminated viable cancer cells while minimally reducing viable BM cells. This finding was confirmed by subsequent positive selection for surviving tumor cells with geneticin. These findings reveal that Taurolidine holds promise for use in BM purging.


Assuntos
Antineoplásicos/farmacologia , Purging da Medula Óssea/métodos , Taurina/farmacologia , Tiadiazinas/farmacologia , Animais , Transplante de Medula Óssea , Quimera , Avaliação Pré-Clínica de Medicamentos , Resistência a Medicamentos/genética , Feminino , Gentamicinas/farmacologia , Células HL-60 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Taurina/análogos & derivados , Transplante Autólogo , Células Tumorais Cultivadas , Ensaio Tumoral de Célula-Tronco
11.
J Ayub Med Coll Abbottabad ; 13(3): 19-21, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11873392

RESUMO

BACKGROUND: Chronic and excessive ethanol consumption is associated with cellular proliferation, fibrosis, cirrhosis and cancer of liver. It was planned to study the effect of alcohol on different biochemical parameters as distribution of these parameters may lead to several complications in gastrointestinal tract, liver, kidney, brain etc. METHODS: 50 alcoholic males and 20 normal subject (with no history of alcohol) with an age ranges 30-45 years were included in the study. Biochemical parameters related to liver were estimated by standard kit. Besides, ions and electrolytes were also determined by standard kit and flame photometry. RESULTS: It was observed that level of alkaline phosphatase, alanine transferase, protein and globulin were significantly increased as compared to normal subjects. Besides, ions like calcium and phosphate were significantly decreased. On the other hand the level of potassium and magnesium was significantly decreased as compared to normal subjects. Electrophoresis shows a protein of 100 Kda is present in the patients sample as compared to control subjects. CONCLUSION: It is therefore concluded that abnormal biochemical function of liver in alcoholism can lead to several complications, hence further research is needed to reach a definite conclusion.


Assuntos
Alcoolismo/metabolismo , Hepatopatias Alcoólicas/metabolismo , Fígado/metabolismo , Adulto , Alcoolismo/complicações , Humanos , Hepatopatias Alcoólicas/etiologia , Masculino , Pessoa de Meia-Idade
12.
Semin Radiat Oncol ; 9(2 Suppl 1): 58-63, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10210541

RESUMO

The beneficial effects of chemotherapy in patients with advanced head and neck cancer remain controversial in terms of survival, but have shown some promise in improving locoregional control and quality of life. In an effort to improve locoregional control and survival, a prospective phase II study was initiated using paclitaxel and carboplatin with concurrent conventional fractionated external-beam radiotherapy. Paclitaxel and carboplatin have both shown excellent radiosensitization through two discrete mechanisms, cell blockage in G2/M phase and inhibition of DNA repair, respectively. Patients were stratified as either operable or inoperable. This report pertains to the inoperable patient group, who received eight cycles of weekly paclitaxel (60 mg/m2), carboplatin (area under the concentration-time curve of 1) with conventional radiotherapy (72 Gy). Chemoradiotherapy was followed by neck dissection for those patients who presented with clinically palpable lymph nodes. Thirty-three patients were enrolled in this group (23 men and 10 women with a median age of 56 years). Eleven patients (33%) had stage III disease; 22 (67%), stage IV disease. The median follow-up period was 14 months. Clinical complete response occurred in 20 patients (60%) and partial response occurred in 10 (30%), for an overall response rate of 90%. Following completion of therapy, 18 patients have undergone biopsy at the primary tumor site and 17 were negative. Eight of the 16 patients with clinically palpable neck nodes at presentation underwent neck dissection; five (63%) had negative nodes. Mucositis was the most common toxicity. Grade 3 or 4 mucositis occurred in 30 of the 33 (90%) patients. Other grade 3 or 4 toxicities included skin (22%), candidiasis (19%), neutropenia (9%), and dehydration (6%). One patient with laryngeal carcinoma who had pathologic complete response developed cartilage necrosis and is undergoing hyperbaric oxygen therapy. Survival data are early but encouraging. Concurrent paclitaxel, carboplatin, and external-beam radiotherapy yielded excellent clinical and pathologic responses. Mucositis remains the most common and significant morbidity. The study will continue for necessary accrual.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Terapia Combinada , Intervalos de Confiança , Feminino , Humanos , Masculino , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Estudos Prospectivos , Dosagem Radioterapêutica , Análise de Sobrevida , Resultado do Tratamento
13.
J Med Chem ; 32(10): 2297-300, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2795601

RESUMO

A number of 2,6-dimethyl-3,5-bis(methoxycarbonyl)-4-substituted-1,4- dihydropyridines were synthesized and evaluated for pregnancy-interceptive activity in mated hamsters. Out of 24 compounds, 12, 15, 21, 22, 28, and 34 caused a marked reduction in the number of implantations when administered on days 3-8 postcoitum. In an in vitro competition assay, none of the compounds exhibited noticeable binding affinity for uterine progesterone receptors. The results reported here have helped to identify new leads for developing pregnancy-interceptive agents and the active compounds do not seem to elicit their interceptive effect through receptor-mediated inhibition of progesterone action in hamster uterus.


Assuntos
Abortivos/síntese química , Di-Hidropiridinas/síntese química , Receptores de Progesterona/efeitos dos fármacos , Útero/metabolismo , Animais , Cricetinae , Citosol/metabolismo , Di-Hidropiridinas/farmacologia , Feminino , Mesocricetus , Estrutura Molecular , Gravidez , Progesterona/metabolismo , Coelhos , Receptores de Progesterona/metabolismo , Valores de Referência , Relação Estrutura-Atividade
14.
Br J Obstet Gynaecol ; 92(11): 1176-8, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2933057

RESUMO

A randomized prospective controlled trial compared a policy of bladder catheterization with no catheterization in patients undergoing laparoscopy. Of the 41 patients randomized to receive no catheterization, seven were actually catheterized on the judgement of the surgeon, but only one of them had greater than 50 ml of urine. Midstream urine obtained 6 days after laparoscopy was infected in 9 (21%) of the 42 patients allocated to receive catheterization and in only five (12%) of those allocated to the no-catheter group. Four of these five were actually not catheterized, giving an infection rate of 12% in the 34 patients not catheterized. The differences are statistically significant. A routine policy of catheterization for patients undergoing laparoscopy is questionable. All patients who are catheterized should be investigated for urinary tract infections after operation.


Assuntos
Laparoscopia , Cateterismo Urinário , Adulto , Ensaios Clínicos como Assunto , Feminino , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Distribuição Aleatória , Bexiga Urinária , Cateterismo Urinário/efeitos adversos , Infecções Urinárias/etiologia
16.
Diabetes ; 28(6): 593-9, 1979 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36318

RESUMO

In the presence of glucose (2 mg/ml), leucine (10 mM) noticeably increased islets' NADPH contents as well as the NADPH:NADP ratio; the changes occurred as soon as 1 min after its addition. NADH concentrations were also increased by leucine. The NADPH:NADP ratio as well as insulin release stimulated by glucose plus leucine were markedly decreased by methylene blue. The thiol oxidants diamide and tert-butyl hydroperoxide also inhibited insulin secretion in response to glucose plus leucine. Employing the perfused pancreas technique, the insulin-releasing action of p-chloromercuribenzoate was further enhanced by leucine. The combined effects were inhibited by tert-butyl hydroperoxide, however. Our data suggest that the insulin-releasing action of leucine depends on the islets' NADPH and reduced glutathione (GSH); in addition, leucine may contribute to insulin secretion by increasing the islet NADPH:NADP ratio and the NADH:NAD ratio. From the data, we assume that the observed increase of NADPH may lead via GSH to an increase in the number of such thiol groups in the beta-cell membrane, which are believed to be related to stimulation of insulin release and, thus, to increase the sensitivity of the beta-cell to stimulation by glucose and/or leucine.


Assuntos
Cloromercurobenzoatos/farmacologia , Glutationa/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Leucina/farmacologia , Azul de Metileno/farmacologia , NADP/metabolismo , NAD/metabolismo , Animais , Feminino , Glucose/farmacologia , Técnicas In Vitro , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Cinética , Masculino , Oxirredução , Perfusão , Ratos
17.
Naunyn Schmiedebergs Arch Pharmacol ; 307(1): 91-6, 1979 May.
Artigo em Inglês | MEDLINE | ID: mdl-384269

RESUMO

Methylene blue (an oxidant of NADPH), diamide (an oxidant of glutathion-SH [GSH]) and tertbutyl hydroperoxide (a substrate of glutathione peroxidase) significantly decreased the GSH content of pancreatic rat islets and decreased their GSH/GSSG ratio. They also significantly depressed the single peak insulin response to tolbutamide by the isolated perfused pancreas as well as its synergistic action with glucose in isolated pancreatic islets. These results suggest that the effect of tolbutamide alone and its synergistic action with glucose could depend on the islet NADPH and GSH. In addition it appears that augmentation of tolbutamide action by glucose in insulin release is mediated by the provision of additional NADPH and GSH through glucose metabolism.


Assuntos
Glutationa/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Azul de Metileno/farmacologia , Oxirredução/efeitos dos fármacos , Compostos de Sulfidrila/metabolismo , Tolbutamida/farmacologia , Animais , Diamida/farmacologia , Feminino , Técnicas In Vitro , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Peróxidos/farmacologia , Ratos
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