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By establishing a profile of the gene-expression responses to cardiopulmonary bypass and cardioplegia, this study allows a better understanding of their effects and provides a framework for the evaluation of new cardiac surgical modalities directly at the genome level.

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Objectives Evaluate the role of serotonin receptors 1B and 2A, thromboxane synthase and receptor and phospholipases A2 and C in response to cardiopulmonary bypass in patients. Methods Atrial tissue was harvested from patients before and after cardiopulmonary bypass with cardioplegia (n=13). Coronary microvessels were assessed for vasoactive response to serotonin with and without inhibitors of 5-HT1B and 5-HT2A receceptors, phospholipase A2 and C. Expression of 5-HT1B and 5-HT2A mRNA was determined by RT-PCR. Expression of 5-HT1B, 5-HT2A, Thromboxane A2 receptor and synthase protein was determined by immunoblotting and immunohistochemistry. Results Exposure of microvessels to serotonin elicited a 7.3 ± 2% relaxation response pre-bypass, changing to a strong contraction response of -19.2 ± 2% after bypass (p<0.001). Addition of either a specific 5-HT1B antagonist or inhibitor of PLA2 resulted in a significant decrease in the contractile response to -8.6 ±1% (p<0.001) and 2.8 ± 3% (p= 0.001), respectively. 5-HT1B receptor mRNA expression increased 1.82 ± 0.34 fold after bypass (p=0.044), while 5-HT2A mRNA expression did not change. 5-HT1B receptor, but not 5-HT2A, protein expression increased after bypass by 1.35 ± 0.7 fold (p=0.0413). Neither thromboxane synthase nor thromboxane receptor expression changed after bypass. Immunohistochemistry demonstrated 5-HT1B receptor increased mainly in the arterial smooth muscle. There was no appreciable difference in arterial expression of either thromboxane synthase or receptor. Conclusion These data indicate that 5-HT-induced vascular dysfunction after cardiopulmonary bypass with cardioplegia may be mediated by increased expression of 5-HT1B receptor and subsequent PLA2 activation in myocardial coronary smooth muscle. Mini Abstract The expression of 5-HT1B receptor protein and mRNA were increased in the atrial myocardium after cardioplegia and cardiopulmonary bypass (CP-CPB). Serotonin elicited a strong contraction response of atrial microvessels after CPB which was mitigated by specific 5-HT1B receptor blockers and phospholipase A2 inhibitors. This suggests that coronary microvascular contraction after CP-CPB is related to increased expression of the 5-HT1B receptor and subsequent phospholipase A2 signaling.

RESUMOAs plantas medicinais são utilizadas desde a antiguidade e esse conhecimento tradicional é passado pelas gerações e podem orientar o estudo de moléculas bioativas, na pesquisa de princípios ativos ou na produção de medicamentos. Os metabólitos secundários são compostos químicos produzidos pelas plantas derivados do metabolismo primário da glicose e atuam na ecologia dos vegetais por meio de funções como atração de polinizadores e dispersores, defesa contra herbivoria e radiação entre outras. A fitoquímica atua no estudo dos metabólitos secundários e a prospecção fitoquímica irá detectar a presença desses e, com isso, orientar as demais etapas do estudo dos vegetais para produção de medicamentos e fitoterápicos. A prospecção pode ser realizada por testes de reações químicas ou por métodos cromatográficos. Os primeiros possuem baixo custo e são mais simples, os segundos necessitam de equipamentos dispendiosos e treinamento adequado para utilização, porém, são mais eficazes no estudo e podem ser utilizados nas demais etapas da investigação fitoquímica. Atualmente, os métodos mais utilizados são por reações químicas e investigações adicionais são realizadas juntamente com a prospecção fitoquímica. Tais estudos são importantes para a pesquisa farmacêutica, para a filogenética e principalmente na preservação dos recursos vegetais dos diferentes biomas brasileiros. PALAVRAS-CHAVE: Farmacognosia, metabolismo vegetal, Plantas medicinais; Química experimental. PHITOCHEMICAL PROSPECTING TECHNIQUES AND THEIR IMPORTANCE TO THE STUDY OF BIOMOLECULAS DERIVED FROM PLANTSABSTRACT Medicinal plants have been used since ancient times and that traditional knowledge is passed through generations and can guide the study of bioactive molecules in the active ingredients research or the production of medicines. Secondary metabolites are chemical compounds produced by plants derived from primary metabolism of glucose and act on the plant ecology through functions such as attracting pollinators

About 3000 tons of beans are not used in human food due to hardening. Several studies on bean-derived bioactive peptides have shown potential to treat some diseases, including those relying on oxidative dysfunctions. We assessed the effects of peptides extracted from hardened bean Phaseolus vulgaris (PV) on reactive oxygen species (ROS) and nitric oxide (NO) production, cytotoxic and cytoprotective effects in endothelial cells, and oxidonitrergic-dependent vasodilating effects. Extract was composed by peptide fraction <3 kDa (PV3) from hardened common bean residue. PV3 sequences were obtained and analyzed with bioinformatics. Human umbilical vein endothelial cells were treated with 10, 20, 30, and 250 µg/mL PV3. Oxidative stress was provoked by 3% H 2 O 2 . Cytotoxicity and cytoprotective effects were evaluated by MTT assay, whereas, ROS and NO were quantified using DHE and DAF-FM fluorescent probes by confocal microscopy. NO- and endothelium-dependent vasodilating effects of PV3 were assessed in isolated aortic rings. We found 35 peptides with an average mass of 1.14 kDa. There were no cell deaths with 10 and 20 μg/mL PV3. PV3 at 30 μg/mL increased cell viability, while cytotoxicity was observed only with 250 μg/mL PV3. PV3 at 10 μg/mL was able to protect cells from oxidative stress. PV3 also increased NO release without causing cell death. It also reduced relative ROS production induced by H 2 O 2 . PV3 vasodilating effects relied on endothelium-dependent NO release. PV3 obtained from low-commercial-value bean displays little cytotoxicity and exerts antioxidant effects, whereas it increases endothelial NO release.

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Background-Given that cardiopulmonary bypass (CPB) is associated with edema and heart dysfunction and that adherens junctions may regulate vascular permeability barrier integrity and cardiomyocyte function, we investigated adherens junction protein steady-state levels in a pig model of CPB. Methods and Results-Pigs were subjected to normothermic CPB for 90 minutes, followed by post-CPB perfusion for 90 minutes. Atrial and ventricular myocardium tissue samples were harvested before institution of bypass (basal levels) and at the end of post-CPB perfusion. Adherens junctions were analyzed by either total lysate or cadherin immunoprecipitates that were immunoblotted for pan-cadherin, VE-cadherin, ␤-catenin, and ␥-catenin. Adherens junction solubility was addressed with Triton X-100 extraction. Frozen tissue sections were labeled with the same antibodies, and adherens junctions were visualized by confocal microscopy. Immunoblotting of total lysates revealed an increase in smallermolecular-weight fragments of VE-cadherin, ␤-catenin, and ␥ -catenin after post-CPB perfusion, indicating partial protein degradation. Smaller-molecular-weight fragments recognized by VE-cadherin and ␤-catenin antibodies were also obtained from VE-cadherin immunoprecipitation, indicating degradation of endothelial cell adherens junctions. A prominent increase in adherens junction complex solubility was observed in post-CPB perfusion samples. Confocal microscopy of hearts obtained before CPB showed a continuous, homogeneous pattern of cell-cell labeling that contrasted with an irregular, discontinuous, punctuate, or zigzag pattern observed in post-CPB perfusion samples, corroborating biochemical data. Conclusions-These results indicate that CPB is associated with signs of degradation of endothelial and cardiomyocytes adherens junctions, pointing to a molecular mechanism leading to increased vascular permeability and cardiomyocyte dysfunction. (Circulation. 2001;104[suppl I]:I-319-I-324.)