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1.
Plants (Basel) ; 12(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36903917

RESUMO

Anthocyanidins are found in nature mainly as pelargonidin, cyanidin, peonidin, delphinidin, petunidin, and malvidin derivatives. These compounds are found free or as glycoside derivatives which are responsible for the color (red, blue, and violet) of some foods and are responsible for attracting seed dispersers. They are grouped into 3-hydroxyanthocyanidins, 3-deoxyanthocyanidins (3D-anth), and O-methylated anthocyanidins. A new method was developed and validated to quantify 3D-anth in plant-rich extracts. To test the new method, Arrabidaea chica Verlot was selected as it is widely used in folk medicine, and it is rich in 3D-anth. The new method was developed by HPLC-DAD and expressed 3D-anth as carajurin content. Carajurin was chosen as the reference standard due to its role as a biological marker for the antileishmanial activity for A. chica. The selected method used a silica-based phenyl column, a mobile phase composed of potassium dihydrogen phosphate buffer, acetonitrile, and methanol, in a gradient elution mode and detection at 480 nm. The method reliability was confirmed by verifying selectivity, linearity, precision, recovery, and robustness. This method contributes to quality control and development of a possible active pharmaceutical ingredient from A. chica as well as it can be used to evaluate 3D-anth in plant extracts with chemical ecology interest.

2.
Front Mol Biosci ; 9: 1032177, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36310604

RESUMO

A Disintegrin and Metalloprotease 17 (ADAM17), also called tumor necrosis factor-ɑ (TNF-ɑ) convertase (TACE), is a well-known protease involved in the sheddase of growth factors, chemokines and cytokines. ADAM17 is also enrolled in hypertension, especially by shedding of angiotensin converting enzyme type 2 (ACE2) leading to impairment of angiotensin 1-7 [Ang-(1-7)] production and injury in vasodilation, induction of renal damage and cardiac hypertrophy. Activation of Mas receptor (MasR) by binding of Ang-(1-7) induces an increase in the nitric oxide (NO) gaseous molecule, which is an essential factor of vascular homeostasis and blood pressure control. On the other hand, TNF-ɑ has demonstrated to stimulate a decrease in nitric oxide bioavailability, triggering a disrupt in endothelium-dependent vasorelaxation. In spite of the previous studies, little knowledge is available about the involvement of the metalloprotease 17 and the NO pathways. Here we will provide an overview of the role of ADAM17 and Its mechanisms implicated with the NO formation.

3.
Oxid Med Cell Longev ; 2022: 9966750, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111166

RESUMO

Plant preparations have been used to treat various diseases and discussed for centuries. Research has advanced to discover and identify the plant components with beneficial effects and reveal their underlying mechanisms. Flavonoids are phytoconstituents with anti-inflammatory, antimutagenic, anticarcinogenic, and antimicrobial properties. Herein, we listed and contextualized various aspects of the protective effects of the flavonols quercetin, isoquercetin, kaempferol, and myricetin and the flavones luteolin, apigenin, 3',4'-dihydroxyflavone, baicalein, scutellarein, lucenin-2, vicenin-2, diosmetin, nobiletin, tangeretin, and 5-O-methyl-scutellarein. We presented their structural characteristics and subclasses, importance, occurrence, and food sources. The bioactive compounds present in our diet, such as fruits and vegetables, may affect the health and disease state. Therefore, we discussed the role of these compounds in inflammation, oxidative mechanisms, and bacterial metabolism; moreover, we discussed their synergism with antibiotics for better disease outcomes. Indiscriminate use of antibiotics allows the emergence of multidrug-resistant bacterial strains; thus, bioactive compounds may be used for adjuvant treatment of infectious diseases caused by resistant and opportunistic bacteria via direct and indirect mechanisms. We also focused on the reported mechanisms and intracellular targets of flavonols and flavones, which support their therapeutic role in inflammatory and infectious diseases.


Assuntos
Anti-Infecciosos , Flavonas , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Apigenina , Flavonas/farmacologia , Flavonoides/farmacologia , Flavonóis/farmacologia , Quempferóis , Luteolina , Preparações de Plantas , Quercetina
4.
J Radiosurg SBRT ; 8(3): 175-180, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36860997

RESUMO

Objectives: Stereotactic radiosurgery (SRS) is part of the multimodality treatment for patients with cancer. The objective of this study is to determine factors which influence overall survival (OS) of Filipino patients who underwent SRS for metastatic tumors of the spine. Methods: This is a retrospective analysis of a cohort of Filipino patients treated with spine SRS for metastatic tumors in a single institution. Putative predictors were determined by the institution's spine SRS team and described in the cohort. A Cox proportional hazards regression model was utilized to construct a model based on the predictors determined by the institution's spine SRS team. Results: A total of 51 consecutive patients with 68 spine metastases were treated with SRS at our institution. The median OS was 13.1 months (95% CI of 7.1 to 19.1). On multivariate analysis, significant predictors that are associated with OS were visceral tumor origin (adjusted HR: 3.08, 95% CI of 1.24 to 7.64, p = 0.015) and cardiovascular disease (adjusted HR: 2.50, 95% CI of 1.04 to 5.94, p = 0.039) with dose and number of fractions as co-variates [Model Wald χ2 (5, N = 51) = 11.11 (p = 0.049)]. Conclusions: The presence of visceral tumor origins and cardiovascular disease are independent factors that are associated with lower overall survival in Filipino patients with spine metastasis treated with SRS.

5.
Anal Methods ; 12(45): 5468-5475, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33141124

RESUMO

Non-destructive methods that allow the quantification of bioproducts in a simple and quick manner during fermentation are extremely desirable from a practical point of view. Therefore, a 9 day fermentation experiment with Schizophyllum commune was carried out to investigate the possibility of using ATR-FTIR to quantify the schizophyllan biopolymer (SPG) directly from the culture medium. On each day, aliquots of the fermentation were taken, and the cell-free supernatant was analyzed by ATR-FTIR. The main objective of this step was to evaluate whether FTIR would be able to detect the appearance of specific peaks related to the production of SPG. The results of the PCA analysis showed that there was a reasonable separation of the days through the FTIR spectra. Then PCA-LDA was applied to the same dataset, which confirmed the formation of groups for each day of fermentation, after which, a calibration and test set was developed. Through a matrix generated by an experimental design with 2 factors and 5 levels, 25 samples were created with variations in the concentration of the culture medium and SPG. The ATR-FTIR spectra of this data set were modeled using PLS regression with backward selection of predictors. The results revealed that the amount of SPG produced can be quantified directly in the culture medium with excellent precision with R2CV = 0.951, R2P = 0.970, RMECV = 0.205 g, RMSEP = 0.170 g, RPDcv = 4.53 and RPDp = 5.88. The traditional method to quantify SPG is time consuming, requires several steps and uses solvents. In contrast, the method proposed in this work is a viable, faster, and a simpler alternative, which does not use reagents and does not require extensive pre-treatment of the samples.

6.
Analyst ; 144(13): 4111-4120, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31172988

RESUMO

The endo-polygalacturonase enzyme (endoPG: EC 3.2.1.15) plays an important role in the fruit juice and wine industries, so the development of new tools for the quantitative and qualitative analysis of its enzymatic action is necessary. In this work, we report the development of a simple, fast and practical method that did not use any chemical reagent to identify and evaluate the action of the endoPG enzyme, produced by the yeast Kluyveromyces marxianus CCT3172, using attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy combined with principal component analysis-linear discriminant analysis (PCA-LDA). This method evaluated the action of the endoPG enzyme on the polygalacturonic acid (PGA) substrate at 5 different times (0, 10, 15, 20 and 30 minutes), and at each time interval the samples were analyzed by ATR-FTIR. It was demonstrated that there was clear segregation between the samples that were and that were not subjected to the action of the endoPG enzyme, and it was also possible to distinguish the samples that were subjected to different incubation times with the enzyme. Through PCA-LDA it was possible to obtain wavelengths that are biomarkers for this enzymatic reaction and the observed changes as a function of hydrolysis duration were found to be in agreement with the breakdown of the glycosidic chain (1011 cm-1-CH-O- CH stretching) of PGA and release of oligosaccharides (1078 cm-1 C-OH elongation). The activity of the endoPG enzyme and the release of galacturonic acid were verified by the dinitrosalicylic acid (DNS) method in all samples. The efficacy of an automatic classifier using a principal component analysis-linear discriminant classifier (PCA-LDC) was evaluated to diagnose the action of the endoPG enzyme. The results showed an accuracy of 100% for the identification of the endoPG enzyme action and from 91.67% to 100% for classification according to the hydrolysis duration in which PGA was exposed to endoPG. The present study indicates that this methodology may be a new approach for the qualitative evaluation of the endoPG enzyme with the potential to be used in laboratories and industries.


Assuntos
Kluyveromyces/enzimologia , Pectinas/química , Poligalacturonase/química , Catálise , Colorimetria , Análise Discriminante , Hidrólise , Cinética , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Neurol Res ; 39(4): 298-304, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28266225

RESUMO

OBJECTIVES: The objectives of this paper are to describe pain control, neurologic improvement, local tumor control, progression-free survival, and overall survival of spine SRS/SFRT patients, and to compare our outcomes with other studies on spine stereotactic radiotherapy for metastatic tumors. METHODS: A chart review of patients who underwent spine SRS/SFRT was done. Information was collected on patient age, sex, histology, site treated, pain relief, local control, neurologic function, prescription dose, and complications. Descriptive statistics, median local control rates, progression-free survival, and overall survival were calculated. RESULTS: Twenty eight SRS and 3 SFRT target volumes in 21 patients were studied. Eighteen underwent SRS and 3 underwent SFRT for metastasis from August 2012 to February 2016. Follow-up ranged from 4 to 41 months. Average dose was 16.6 ± 3.9 Gy. Spine SRS mean target volume was 31.1 cc (95% CI, 21.7-40.6 cc). Median overall survival after treatment was 16 months (95% CI, 9.7-22.3 months) and median progression-free survival was 13 months (95% CI, 8.4-17.6 months). Local control was 46%, 30%, and 15% at 6, 8, and 10 months, respectively. Average onset of pain relief is 4.9 days (95% CI, 0.8-8.9 days). One patient (5%) developed post SRS vertebral compression fracture. CONCLUSION: SRS/SFRT is a safe and effective alternative to EBRT for the treatment of spine metastasis. Improvement in pain control and motor strength and incidence of adverse events are comparable with other studies. Local tumor control was lower in our series due to a lower mean prescribed dose.


Assuntos
Radiocirurgia/métodos , Neoplasias da Coluna Vertebral/secundário , Neoplasias da Coluna Vertebral/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Dor do Câncer/fisiopatologia , Dor do Câncer/cirurgia , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Radiocirurgia/efeitos adversos , Radiocirurgia/economia , Neoplasias da Coluna Vertebral/mortalidade , Neoplasias da Coluna Vertebral/fisiopatologia , Resultado do Tratamento , Adulto Jovem
8.
Curr Mol Med ; 16(7): 631-649, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27492800

RESUMO

The testes are one of the most delicate organs in the male body and highly susceptible to the exogenous influences capable of inducing cell damage. Cancer therapies are well known to negatively affect the male reproductive tract with a severe impairment of spermatogenesis and infertility. The present work aimed to systematically review the available information about the different endogenous factors (hormonal and nonhormonal) that may have protective or advantageous properties on the recovery of male reproductive function after gonadal injury. Furthermore, the perspective that these endogenous molecules could act as cryoprotectants to improve the quality of cryopreserved semen samples was also discussed. The knowledge reviewed herein allowed to identify promising factors able to mitigate the male fertility problems arising either from oncological treatments or other gonadal damage, and opened new possibilities to ameliorate the recovery of spermatogenesis or to preserve fertility.


Assuntos
Preservação da Fertilidade , Neoplasias Testiculares/metabolismo , Testículo/fisiopatologia , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Humanos , Masculino , Fatores de Proteção , Lesões por Radiação/terapia , Recuperação de Função Fisiológica , Espermatogênese , Neoplasias Testiculares/terapia , Testículo/metabolismo , Testículo/patologia , Testosterona/fisiologia
9.
Curr Mol Med ; 16(7): 607-619, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27411833

RESUMO

Regucalcin (RGN) is a multifunctional protein that was first described as a calcium (Ca2+)-binding protein playing a relevant role in the maintenance of intracellular Ca2+ concentration. However, due to its downregulated expression with aging, RGN is also known as senescence marker protein-30. The RGN protein is an X-chromosome gene product, whose transcription is regulated by a myriad of hormonal and non-hormonal factors. Besides the well-known role in Ca2+ homeostasis, RGN has also been linked to the control of several intracellular signaling pathways, and basic biological processes, such as oxidative stress, cell proliferation, apoptosis, and metabolism. RGN has been shown to have antioxidant properties by its activity reducing the production of reactive oxygen species and increasing the antioxidant defenses. The role of RGN suppressing cell proliferation is associated with the regulation of expression of oncogenes and tumor suppressor genes. It results clear that all the existent knowledge implicates RGN in the control of the main biological processes actually recognized as the hallmarks of cancer. Moreover, it has been shown that tumor onset and progression are underpinned by the loss of RGN expression, whereas RGN overexpression showed to have a protective role against the development of chemicallyinduced tumors. This review describes the mechanisms that control the tissue expression of RGN and discusses the experimental evidence that indicate RGN as a new tumor suppressor protein.


Assuntos
Proteínas de Ligação ao Cálcio/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Neoplasias/metabolismo , Proteínas Supressoras de Tumor/fisiologia , Animais , Apoptose , Carcinogênese/metabolismo , Proliferação de Células , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/patologia
10.
J. bras. patol. med. lab ; 51(1): 48-51, Jan-Feb/2015. graf
Artigo em Inglês | LILACS | ID: lil-746531

RESUMO

Adrenal myelolipomas are unusual benign tumors with an average age of 60 years at onset, often associated with adrenal gland. A 63-year-old female presenting with abdominal discomfort and a large expanding mass in retroperitoneum occupying the right hemiabdomen, with extrinsic compression of adjacent organs, underwent tumor resection. Macroscopic examination of the surgical specimen showed a large yellowish homogeneous lesion with areas of hemorrhage, covered by a thin fibrous capsule. Microscopic analysis revealed a neoplasm composed of mature adipocytes permeated by hematopoietic tissue. There was residual adrenal cortex around the lesion.


Mielolipomas são tumores benignos pouco comuns, com média de incidência de 60 anos, frequentemente associados à glândula adrenal. Relata-se caso de paciente do sexo feminino de 63 anos que apresentava quadro clínico de desconforto abdominal e volumosa formação expansiva em retroperitônio, ocupando hemiabdômen direito com compressão extrínseca de órgãos adjacentes, sendo submetida à ressecção tumoral. A análise macroscópica da peça cirúrgica mostrou volumosa lesão homogênea amarelada com áreas de hemorragia, recoberta por fina cápsula fibrosa. A análise microscópica revelou neoplasia constituída por adipócitos maduros permeados por tecido hematopoiético, notando-se cortical da suprarrenal residual na periferia da lesão.

11.
Biomed Res Int ; 2014: 694934, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25045693

RESUMO

Promastigote forms of Leishmania amazonensis were treated with different concentrations of two fractions of Curcuma longa cortex rich in turmerones and their respective liposomal formulations in order to evaluate growth inhibition and the minimal inhibitory concentration (MIC). In addition, cellular alterations of treated promastigotes were investigated under transmission and scanning electron microscopies. LipoRHIC and LipoRHIWC presented lower MIC, 5.5 and 12.5 µg/mL, when compared to nonencapsulated fractions (125 and 250 µg/mL), respectively, and to ar-turmerone (50 µg/mL). Parasite growth inhibition was demonstrated to be dose-dependent. Important morphological changes as rounded body and presence of several roles on plasmatic membrane could be seen on L. amazonensis promastigotes after treatment with subinhibitory concentration (2.75 µg/mL) of the most active LipoRHIC. In that sense, the hexane fraction from the turmeric cortex of Curcuma longa incorporated in liposomal formulation (LipoRHIC) could represent good strategy for the development of new antileishmanial agent.


Assuntos
Cetonas/administração & dosagem , Leishmaniose/tratamento farmacológico , Lipossomos/administração & dosagem , Extratos Vegetais/administração & dosagem , Sesquiterpenos/administração & dosagem , Química Farmacêutica , Curcuma/química , Hexanos/química , Humanos , Cetonas/química , Leishmania/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Leishmania mexicana/patogenicidade , Leishmaniose/parasitologia , Lipossomos/química , Extratos Vegetais/química , Sesquiterpenos/química
12.
Rev. bras. farmacogn ; 24(2): 215-224, Mar-Apr/2014. tab
Artigo em Inglês | LILACS | ID: lil-714769

RESUMO

The aim of this study was to compile the traditional knowledge about plants used for the treatment of giardiasis, and also to carry out experimental research to evaluate the anti-Giardia activity of five species.To reach this objective, 398 interviews were performed using a previously prepared questionnaire, followed by an in vitro evaluation of giardicidal potential of hydroalcoholic leaf extracts of Anacardium occidentale L., Chenopodium ambrosioides L., Passiflora edulis Sims, Psidium guajava L., and Stachytarpheta cayennensis (Rich.) Vahl. Among the interviewed people, 55.53% reported the use of plants to treat diarrhea, the most severe symptom of giardiasis. The results indicated 36 species used by this population for these problems. The use of leaves (72.50%) of a single plant (64.25%) collected from backyards and gardens (44.34%) and prepared by decoction were predominant. The majority of the interviewees (85.52%) attributed their cure to the use of plants. In the experimental tests, all extracts inhibited the growth of Giardia lamblia trophozoites in different intensities: A. occidentale and P. guajava extracts elicited a moderate activity (250 ≤ IC50 ≤ 500 μg/ml), C. ambrosioides and S. cayennensis extracts evoked a high activity (100 ≤ IC50 ≤ 250 μg/ml), and P. edulis extract showed very high activity (IC50 ≤ 100 μg/ml). This study shows that an ethnopharmacological approach is useful in the selection of plant materials with potential giardicidal activity.

13.
Andrology ; 2(2): 290-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24519986

RESUMO

Recent evidence suggested the involvement of calcium-binding protein regucalcin (RGN) in testicular apoptosis. Herein, we investigated the role of RGN controlling apoptotic pathways in the testis by using a transgenic rat model overexpressing RGN (Tg-RGN). Seminiferous tubules (SeT) from Tg-RGN and their wild-type (Wt) counterparts were cultured ex vivo in presence or absence of apoptosis inducers thapsigargin (Thap, 10(-7) and 10(-6) m) and actinomycin D (Act D, 0.5 and 1 µg/mL). Expression levels of key regulators of apoptosis in SeT of Tg-RGN and Wt animals were determined by quantitative real-time PCR and Western blot analysis. Measurement of caspase-3 enzymatic activity was included as an end point of apoptosis. Tg-RGN SeT treated with 10(-6) m of Thap or 1 µg/mL of Act D showed a diminished enzymatic activity and gene transcription of caspase-3, along with increased mRNA and protein expression of antiapoptotic Bcl-2. Bcl-2/Bax (antiapoptotic/proapoptotic) protein ratio was also enhanced in these SeT. Although caspase-9 mRNA was increased in the SeT of Tg-RGN treated with Thap, no differences were observed at protein level, and no differences were also found on protein levels of apoptosis-inducing factor. mRNA expression of proapoptotic p53 and p21 was strongly decreased in Tg-RGN SeT treated with Thap (10(-6) m) or Act D (1 µg/mL). These findings demonstrated that RGN suppresses Thap- and Act D-induced apoptosis in SeT by modulating the expression and activity of key apoptotic and antiapoptotic factors. Moreover, results indicate that RGN overexpression protects germ cell from apoptosis induced by noxious stimuli, which could be a relevant mechanism for fertility preservation in situations of oncological treatments.


Assuntos
Apoptose/genética , Proteínas de Ligação ao Cálcio/biossíntese , Dactinomicina/farmacocinética , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Tapsigargina/farmacologia , Animais , Proteínas de Ligação ao Cálcio/genética , Hidrolases de Éster Carboxílico , Caspase 3/biossíntese , Caspase 3/genética , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidores Enzimáticos/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Inibidores da Síntese de Ácido Nucleico/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Ratos Transgênicos , Testículo/fisiologia , Transcrição Gênica , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética
14.
Br J Pharmacol ; 171(4): 1033-42, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24261663

RESUMO

BACKGROUND AND PURPOSE: Metformin is commonly used to treat type 2 diabetes (T2D). While new clinical applications have been ascribed to metformin, including treatment of anovulatory infertility, its effects on male reproduction have not been investigated. The Sertoli cell (SC) is crucial for germ cell development, exerting metabolic control of spermatogenesis, therefore, we investigated the effects of metformin on SC metabolism. EXPERIMENTAL APPROACH: Rat SCs were cultured in the absence and presence of metformin (5, 50 and 500 µM). mRNA and protein levels of glucose transporters (GLUT1 and GLUT3), phosphofructokinase 1 (PFK 1), lactate dehydrogenase (LDH) and monocarboxylate transporter 4 (MCT4) were determined by quantitative PCR and Western blot respectively. LDH activity was assessed and metabolite production/consumption determined by (1) H-NMR. KEY RESULTS: Metformin (50 µM) decreased mRNA and protein levels of GLUT1, GLUT3, MCT4 and PFK 1 but did not affect LDH mRNA or protein levels. However, although glucose consumption was maintained in metformin-treated cells, LDH activity, lactate and alanine production were increased, indicating an enhanced glycolytic flux. No metabolic cytotoxicity was detected in SCs exposed to supra-pharmacological concentration of metformin. CONCLUSIONS AND IMPLICATIONS: Our results indicate that metformin: (i) decreases mRNA and protein levels of glycolysis-related transporters in SCs but increases their activity; and (ii) stimulates alanine production, which induces antioxidant activity and maintains the NADH/NAD(+) equilibrium. The increased lactate in metformin-treated SCs provides nutritional support and has an anti-apoptotic effect in developing germ cells. Thus, metformin can be considered as a suitable antidiabetic drug for male patients of reproductive age with T2D.


Assuntos
Hipoglicemiantes/farmacologia , Metformina/farmacologia , Células de Sertoli/efeitos dos fármacos , Alanina/metabolismo , Animais , Células Cultivadas , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 3/genética , Transportador de Glucose Tipo 3/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , Masculino , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Fosfofrutoquinase-1/genética , Fosfofrutoquinase-1/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reprodução , Células de Sertoli/metabolismo
15.
Curr Med Chem ; 20(32): 4037-49, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23931280

RESUMO

Bicarbonate (HCO3⁻) membrane transport systems are crucial players in the physiology of several tissues. The molecular basis of HCO3⁻ membrane transport is of major physiological relevance since this ion is involved in the establishment of intracellular and extracellular ionic composition, osmolariy and pH. The membrane HCO3⁻ transporters are divided in two main families: solute carrier 4 (SLC4) and solute carrier 26 (SLC26), although HCO3⁻ concentration can also be regulated by the cystic fibrosis transmembrane regulator (CFTR). In most tissues the SLC4 family represents the majority of HCO3⁻ transporters members, which can be divided in two subgroups: the Na⁺-dependent and the Na⁺-independent transporters. The SLC26 family consists of ten members that can transport diverse ions besides HCO3⁻. In the male reproductive tract, HCO3⁻ transport occurs in several processes in order to assure a correct pursuance of the spermatogenetic event and spermatozoa capacitation, being also necessary for egg fertilization. Indeed, the formation of competent spermatozoa, the maintenance of an adequate ductal luminal milieu and spermatozoa capacitation are highly dependent of ionic balance and pH. Perturbations in these processes result in reduced male reproductive health and consequently male subfertility and/or infertility. Thus, it is imperative to understand HCO3⁻ transport dynamics in order to identify and counteract possible alterations related with reduced male fertility caused by pathological conditions. Herein, we will review the major families and subfamilies of HCO3⁻ membrane transport, discussing the molecular basis of HCO3⁻ transport in the male reproductive tract and its role in male-associated subfertility and/or infertility.


Assuntos
Bicarbonatos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Ducto Deferente/metabolismo , Animais , Bicarbonatos/química , Transporte Biológico/fisiologia , Humanos , Concentração de Íons de Hidrogênio , Masculino
16.
Environ Manage ; 52(2): 427-40, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23636205

RESUMO

Tropical forest countries are struggling with the partially conflicting policy objectives of socioeconomic development, forest conservation, and safeguarding the livelihoods of local forest-dependent people. We worked with communities in the lower Tapajós region of the central Brazilian Amazon for over 10 years to understand their traditional and present land use practices, the constraints, and decision making processes imposed by their biophysical, socioeconomic, and political environment, and to facilitate development trajectories to improve the livelihoods of forest communities while conserving the forest on the farms and in the larger landscape. The work focused on riverine communities initially in the Tapajós National Forest and then in the Tapajós-Arapiuns Extractive Reserve. These communities have a century-old tradition of planting rubber agroforests which despite their abandonment during the 1990s still widely characterize the vegetation of the river banks, especially in the two protected areas where they are safe from the recent expansion of mechanized rice and soybean agriculture. The project evolved from the capacity-building of communities in techniques to increase the productivity of the rubber agroforests without breaking their low-input and low-risk logic, to the establishment of a community enterprise that allowed reserve inhabitants to reforest their own land with tree species of their choice and sell reforestation (not carbon) credits to local timber companies while retaining the ownership of the trees. By making land use practices economically more viable and ecologically more appropriate for protected areas, the project shows ways to strengthen the system of extractive and sustainable development reserves that protects millions of hectares of Amazon forest with the consent of the communities that inhabit them.


Assuntos
Agricultura , Agricultura Florestal , Hevea , Brasil , Conservação dos Recursos Naturais , Invenções
17.
Andrology ; 1(3): 495-504, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23495257

RESUMO

Diabetes mellitus is a metabolic disorder that may arise from diet habits and is growing to epidemic proportions. Young male diabetic patients present high infertility/subfertility prevalence resulting from impaired reproductive function and poor semen quality. We aimed to evaluate the effects of a high-energy diet (HED) on glucose tolerance/insulin levels and correlate the observed effects on male reproductive function with overall testicular metabolism. After 1 month, HED fed rats showed increased glycaemic levels, impaired glucose tolerance and hypoinsulinaemia. Moreover, an imbalance of intratesticular and serum testosterone levels was observed, whereas those of 17ß-estradiol were not altered. High-energy diet also affected the reproductive parameters, with HED rats exhibiting a significant increase in abnormal sperm morphology. Glycolytic metabolism was favoured in testicles of HED rats with an increased expression of both glucose transporters 1 (GLUT1) and 3 (GLUT3) and the enzyme phosphofrutokinase 1. Moreover, lactate production and the expression of metabolism-associated genes and proteins involved in lactate production and transport were also enhanced by HED. Alanine testicular content was decreased and thus intratesticular lactate/alanine ratio in HED rats was increased, suggesting increased oxidative stress. Other energetic substrates such as acetate and creatine were not altered in testis from HED rats, but intratesticular glycine content was increased in those animals. Taken together, these results suggest that HED induces a pre-diabetic state that may impair reproductive function by modulating overall testicular metabolism. This is the first report on testicular metabolic features and mechanisms related with the onset of a pre-diabetic state.


Assuntos
Dieta , Ingestão de Energia , Reprodução , Testículo/metabolismo , Alanina/metabolismo , Animais , Primers do DNA , Teste de Tolerância a Glucose , Glicina/metabolismo , Glicólise , Insulina/sangue , Ácido Láctico/metabolismo , Masculino , Reação em Cadeia da Polimerase , Ratos , Ratos Wistar , Motilidade dos Espermatozoides , Testículo/fisiologia
18.
Reprod Toxicol ; 38: 81-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23538319

RESUMO

The purpose of this study was to determine the effects of 2,4-D, an herbicide used worldwide also known as endocrine disruptor, in Sertoli cell (SC) metabolism. Immature rat SCs were maintained 50h under basal conditions or exposed to 2,4-D (100nM, 10µM and 1mM). SCs exposed to 10µM and 1mM of 2,4-D presented lower intracellular glucose and lactate content. Exposure to 10µM of 2,4-D induced a significant decrease in glucose transporter-3 mRNA levels and phosphofructokinase-1 mRNA levels decreased in cells exposed to 100nM and 10µM of 2,4-D. Exposure to 100nM and 10µM also induced a decrease in lactate dehydrogenase (LDH) mRNA levels while the LDH protein levels were only decreased in cells exposed to 1mM of 2,4-D. Exposure to 2,4-D altered glucose uptake and metabolization in SCs, as well as lactate metabolism and export that may result in impaired spermatogenesis.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Disruptores Endócrinos/toxicidade , Glucose/metabolismo , Herbicidas/toxicidade , Células de Sertoli/efeitos dos fármacos , Alanina/metabolismo , Animais , Células Cultivadas , Transportador de Glucose Tipo 3/genética , Transportador de Glucose Tipo 3/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , Masculino , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Fosfofrutoquinase-1/genética , Fosfofrutoquinase-1/metabolismo , Ratos , Ratos Wistar , Células de Sertoli/metabolismo
19.
Biochim Biophys Acta ; 1832(5): 626-35, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23348098

RESUMO

Diabetes mellitus (DM) is one of the greatest public health threats in modern societies. Although during a few years it was suggested that DM had no significant effect in male reproductive function, this view has been challenged in recent years. The increasing incidence of DM worldwide will inevitably result in a higher prevalence of this pathology in men of reproductive age and subfertility or infertility associated with DM is expected to dramatically rise in upcoming years. From a clinical perspective, the evaluation of semen parameters, as well as spermatozoa deoxyribonucleic acid (DNA) integrity, are often studied due to their direct implications in natural and assisted conception. Nevertheless, recent studies based on the molecular mechanisms beyond glucose transport in testicular cells provide new insights in DM-induced alterations in male reproductive health. Testicular cells have their own glucose sensing machinery that react to hormonal fluctuations and have several mechanisms to counteract hyper- and hypoglycemic events. Moreover, the metabolic cooperation between testicular cells is crucial for normal spermatogenesis. Sertoli cells (SCs), which are the main components of blood-testis barrier, are not only responsible for the physical support of germ cells but also for lactate production that is then metabolized by the developing germ cells. Any alteration in this tied metabolic cooperation may have a dramatic consequence in male fertility potential. Therefore, we present an overview of the clinical significance of DM in the male reproductive health with emphasis on the molecular mechanisms beyond glucose fluctuation and transport in testicular cells.


Assuntos
Complicações do Diabetes/metabolismo , Glucose/metabolismo , Infertilidade Masculina/metabolismo , Transporte Biológico , Complicações do Diabetes/complicações , Humanos , Infertilidade Masculina/complicações , Ácido Láctico/metabolismo , Masculino , Modelos Biológicos , Espermatozoides/metabolismo , Testículo/metabolismo
20.
Brain Res ; 1491: 23-33, 2013 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-23131585

RESUMO

Aluminum (Al) is a neurotoxic agent with deleterious actions on cognitive processes. Nevertheless, few studies have investigated the neuropathological effects underlying the Al-induced cognitive impairment. We have explored the effects of acute Al citrate intoxication on both hippocampal morphology and mnemonic processes in rodents. Adult male Wistar rats were intoxicated with a daily dose of Al citrate (320 mg/kg) during 4 days by gavage. Animals were perfused at 8 (G2), 17 (G3) and 31 days (G4) after intoxication. Control animals were treated with sodium citrate (G1). Animals were submitted to behavioral tests of open field and elevated T-maze. Immunohistochemistry was performed to label neurons (anti-NeuN) and astrocytes (anti-GFAP) in both CA1 and CA3 hippocampal regions. There was an increase in the locomotor activity in open field test for G2 in comparison to control group and other groups (ANOVA-Bonferroni, P<0.05). The elevated T-maze avoidance latency (AL) was higher in all intoxicated groups compared to control (P<0.05) in avoidance 1. These values remained elevated in avoidance 2 (P<0.05), but abruptly decreased in G2 and G3, but not in G1 and G4 animals in avoidance 3 (P<0.05). There were no significant differences for 1 and 2 escape latencies. There were intense neuronal loss and a progressive decrease in GFAP immunoreactivity in the hippocampus of intoxicated animals. The results suggest that Al citrate treatment induces deficits on learning and memory concomitant with neuronal loss and astrocyte impairment in the hippocampus of intoxicated rats.


Assuntos
Ácido Cítrico , Transtornos Cognitivos/patologia , Proteína Glial Fibrilar Ácida/metabolismo , Hipocampo/patologia , Neurônios/patologia , Síndromes Neurotóxicas/patologia , Análise de Variância , Animais , Ansiedade/psicologia , Astrócitos/efeitos dos fármacos , Aprendizagem da Esquiva/efeitos dos fármacos , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/psicologia , Hipocampo/metabolismo , Imuno-Histoquímica , Deficiências da Aprendizagem/induzido quimicamente , Deficiências da Aprendizagem/psicologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/patologia , Atividade Motora/fisiologia , Neurônios/metabolismo , Síndromes Neurotóxicas/psicologia , Desempenho Psicomotor/fisiologia , Ratos , Ratos Wistar , Sobrevida
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