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Jose Manuel Martínez-martos - One of the best experts on this subject based on the ideXlab platform.
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Neoadjuvant chemotherapy modifies serum Angiotensinase activities in women with breast cancer.
Maturitas, 2012Co-Authors: Maria Jesus Ramírez-expósito, Maria Dolores Mayas, María Pilar Carrera-gonzález, Basilio Dueñas, Julia Martínez-ferrol, Jose Manuel Martínez-martosAbstract:Abstract Purpose The aim of this study was to investigate the putative changes in serum Angiotensinase activities (aminopeptidase N, APN; aminopeptidase B, APB; aminopeptidase A, APA; aspartyl aminopeptidase, ASAP) involved in the renin–angiotensin system (RAS) in women with breast cancer treated or not with a neoadjuvant therapy of paclitaxel and anthracycline and in healthy women volunteers. Methods We fluorometrically analysed serum APN, APB, APA and ASAP activities using their corresponding aminoacyl-β-naphthylamides as substrates in women with breast cancer treated with a neoadjuvant therapy of paclitaxel and anthracycline. Results When compared with healthy controls, women with breast cancer not treated with neoadjuvant chemotherapy, showed a decrease in Angiotensinase activity, which support the putative increase of angiotensin II (Ang II) levels, indicating that the tumour process would favour the development of the disease. Also, an increase in APN and APB activities was observed, which support a role for angiotensin IV (Ang IV). In women treated with a neoadjuvant therapy, we described an increase in ASAP and APA activities, supporting the idea that this treatment increases Ang II catabolism. The resulting decrease in Ang II level could lead to an inhibition of the tumour growth. Conclusion Present results show changes in serum Angiotensinase activities in women with breast cancer and in women with breast cancer treated with a neoadjuvant therapy of paclitaxel and anthracycline. Therefore, considerable attention should be focused on the development of RAS blockade therapy as a new strategy for breast cancer treatment.
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Mammary renin–angiotensin system-regulating aminopeptidase activities are modified in rats with breast cancer
Tumor Biology, 2010Co-Authors: Maria Pilar Carrera, Maria Jesus Ramírez-expósito, Maria Dolores Mayas, Maria Jesus García, Jose Manuel Martínez-martosAbstract:Angiotensin II in particular and/or the local renin–angiotensin system in general could have an important role in epithelial tissue growth and modelling; therefore, it is possible that it may be involved in breast cancer. In this sense, previous works of our group showed a predominating role of angiotensin II in tumoral tissue obtained from women with breast cancer. However, although classically angiotensin II has been considered the main effector peptide of the renin–angiotensin system cascade, several of its catabolism products such as angiotensin III and angiotensin IV also possess biological functions. These peptides are formed through the activity of several proteolytic regulatory enzymes of the aminopeptidase type, also called Angiotensinases. The aim of this work was to analyse several specific Angiotensinase activities involved in the renin–angiotensin system cascade in mammary tissue from control rats and from rats with mammary tumours induced by N -methyl-nitrosourea (NMU), which may reflect the functional status of their target peptides under the specific conditions brought about by the tumoural process. The results show that soluble and membrane-bound specific aspartyl aminopeptidase activities and membrane-bound glutamyl aminopeptidase activity increased in mammary tissue from NMU-treated animals and soluble aminopeptidase N and aminopeptidase B activities significantly decreased in mammary tissue from NMU-treated rats. These changes support the existence of a local mammary renin–angiotensin system and that this system and its putative functions in breast tissue could be altered by the tumour process, in which we suggest a predominant role of angiotensin III. All described data about the renin–angiotensin system in mammary tissue support the idea that it must be involved in normal breast tissue functions, and its disruption could be involved in one or more steps of the carcinogenesis process.
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Angiotensinase Activity and Olive Oil Supplementation
Olives and olive oil in health and disease prevention, 2010Co-Authors: Maria Jesus Ramírez-expósito, M. P. Carrera, Jose Manuel Martínez-martosAbstract:Publisher Summary Hypertension is a major risk factor for coronary heart disease, congestive heart failure, stroke, and renal disease. Several studies have demonstrated a reduced incidence of hypertension in populations that consume the Mediterranean diet. Although the Mediterranean diet is rich in fiber, fish, fruits, and vegetables, olive oil is its major component and, therefore, represents the major energy source. Several studies have demonstrated the antihypertensive properties of olive oil in animal models, epidemiological studies, and feeding trials. Olive oil's precise mechanisms of action for blood pressure reduction are unknown, although several theories have been proposed, including the existence of specific antihypertensive molecules such as 2-hydroxyoleic acid; the presence of polyphenols such as oleuropein, hydroxytyrosol, tyrosol, and caffeic acid, with an important antioxidant effect; a general improvement of both monounsaturated fatty acids and/or a non-lipid fraction of olive oil in endothelial function; and the role of olive oil as a calcium channel antagonist. The chapter also proposes that dietary olive oil affects both the circulating and tissue renin–angiotensin systems (RAS) through their regulating Angiotensinases. These systems are involved in the pathogenesis of hypertension, but also in several biological functions, which could also be affected.
Maria Jesus Ramírez-expósito - One of the best experts on this subject based on the ideXlab platform.
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Neoadjuvant chemotherapy modifies serum Angiotensinase activities in women with breast cancer.
Maturitas, 2012Co-Authors: Maria Jesus Ramírez-expósito, Maria Dolores Mayas, María Pilar Carrera-gonzález, Basilio Dueñas, Julia Martínez-ferrol, Jose Manuel Martínez-martosAbstract:Abstract Purpose The aim of this study was to investigate the putative changes in serum Angiotensinase activities (aminopeptidase N, APN; aminopeptidase B, APB; aminopeptidase A, APA; aspartyl aminopeptidase, ASAP) involved in the renin–angiotensin system (RAS) in women with breast cancer treated or not with a neoadjuvant therapy of paclitaxel and anthracycline and in healthy women volunteers. Methods We fluorometrically analysed serum APN, APB, APA and ASAP activities using their corresponding aminoacyl-β-naphthylamides as substrates in women with breast cancer treated with a neoadjuvant therapy of paclitaxel and anthracycline. Results When compared with healthy controls, women with breast cancer not treated with neoadjuvant chemotherapy, showed a decrease in Angiotensinase activity, which support the putative increase of angiotensin II (Ang II) levels, indicating that the tumour process would favour the development of the disease. Also, an increase in APN and APB activities was observed, which support a role for angiotensin IV (Ang IV). In women treated with a neoadjuvant therapy, we described an increase in ASAP and APA activities, supporting the idea that this treatment increases Ang II catabolism. The resulting decrease in Ang II level could lead to an inhibition of the tumour growth. Conclusion Present results show changes in serum Angiotensinase activities in women with breast cancer and in women with breast cancer treated with a neoadjuvant therapy of paclitaxel and anthracycline. Therefore, considerable attention should be focused on the development of RAS blockade therapy as a new strategy for breast cancer treatment.
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Mammary renin–angiotensin system-regulating aminopeptidase activities are modified in rats with breast cancer
Tumor Biology, 2010Co-Authors: Maria Pilar Carrera, Maria Jesus Ramírez-expósito, Maria Dolores Mayas, Maria Jesus García, Jose Manuel Martínez-martosAbstract:Angiotensin II in particular and/or the local renin–angiotensin system in general could have an important role in epithelial tissue growth and modelling; therefore, it is possible that it may be involved in breast cancer. In this sense, previous works of our group showed a predominating role of angiotensin II in tumoral tissue obtained from women with breast cancer. However, although classically angiotensin II has been considered the main effector peptide of the renin–angiotensin system cascade, several of its catabolism products such as angiotensin III and angiotensin IV also possess biological functions. These peptides are formed through the activity of several proteolytic regulatory enzymes of the aminopeptidase type, also called Angiotensinases. The aim of this work was to analyse several specific Angiotensinase activities involved in the renin–angiotensin system cascade in mammary tissue from control rats and from rats with mammary tumours induced by N -methyl-nitrosourea (NMU), which may reflect the functional status of their target peptides under the specific conditions brought about by the tumoural process. The results show that soluble and membrane-bound specific aspartyl aminopeptidase activities and membrane-bound glutamyl aminopeptidase activity increased in mammary tissue from NMU-treated animals and soluble aminopeptidase N and aminopeptidase B activities significantly decreased in mammary tissue from NMU-treated rats. These changes support the existence of a local mammary renin–angiotensin system and that this system and its putative functions in breast tissue could be altered by the tumour process, in which we suggest a predominant role of angiotensin III. All described data about the renin–angiotensin system in mammary tissue support the idea that it must be involved in normal breast tissue functions, and its disruption could be involved in one or more steps of the carcinogenesis process.
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Angiotensinase Activity and Olive Oil Supplementation
Olives and olive oil in health and disease prevention, 2010Co-Authors: Maria Jesus Ramírez-expósito, M. P. Carrera, Jose Manuel Martínez-martosAbstract:Publisher Summary Hypertension is a major risk factor for coronary heart disease, congestive heart failure, stroke, and renal disease. Several studies have demonstrated a reduced incidence of hypertension in populations that consume the Mediterranean diet. Although the Mediterranean diet is rich in fiber, fish, fruits, and vegetables, olive oil is its major component and, therefore, represents the major energy source. Several studies have demonstrated the antihypertensive properties of olive oil in animal models, epidemiological studies, and feeding trials. Olive oil's precise mechanisms of action for blood pressure reduction are unknown, although several theories have been proposed, including the existence of specific antihypertensive molecules such as 2-hydroxyoleic acid; the presence of polyphenols such as oleuropein, hydroxytyrosol, tyrosol, and caffeic acid, with an important antioxidant effect; a general improvement of both monounsaturated fatty acids and/or a non-lipid fraction of olive oil in endothelial function; and the role of olive oil as a calcium channel antagonist. The chapter also proposes that dietary olive oil affects both the circulating and tissue renin–angiotensin systems (RAS) through their regulating Angiotensinases. These systems are involved in the pathogenesis of hypertension, but also in several biological functions, which could also be affected.
Maria Dolores Mayas - One of the best experts on this subject based on the ideXlab platform.
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Neoadjuvant chemotherapy modifies serum Angiotensinase activities in women with breast cancer.
Maturitas, 2012Co-Authors: Maria Jesus Ramírez-expósito, Maria Dolores Mayas, María Pilar Carrera-gonzález, Basilio Dueñas, Julia Martínez-ferrol, Jose Manuel Martínez-martosAbstract:Abstract Purpose The aim of this study was to investigate the putative changes in serum Angiotensinase activities (aminopeptidase N, APN; aminopeptidase B, APB; aminopeptidase A, APA; aspartyl aminopeptidase, ASAP) involved in the renin–angiotensin system (RAS) in women with breast cancer treated or not with a neoadjuvant therapy of paclitaxel and anthracycline and in healthy women volunteers. Methods We fluorometrically analysed serum APN, APB, APA and ASAP activities using their corresponding aminoacyl-β-naphthylamides as substrates in women with breast cancer treated with a neoadjuvant therapy of paclitaxel and anthracycline. Results When compared with healthy controls, women with breast cancer not treated with neoadjuvant chemotherapy, showed a decrease in Angiotensinase activity, which support the putative increase of angiotensin II (Ang II) levels, indicating that the tumour process would favour the development of the disease. Also, an increase in APN and APB activities was observed, which support a role for angiotensin IV (Ang IV). In women treated with a neoadjuvant therapy, we described an increase in ASAP and APA activities, supporting the idea that this treatment increases Ang II catabolism. The resulting decrease in Ang II level could lead to an inhibition of the tumour growth. Conclusion Present results show changes in serum Angiotensinase activities in women with breast cancer and in women with breast cancer treated with a neoadjuvant therapy of paclitaxel and anthracycline. Therefore, considerable attention should be focused on the development of RAS blockade therapy as a new strategy for breast cancer treatment.
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Mammary renin–angiotensin system-regulating aminopeptidase activities are modified in rats with breast cancer
Tumor Biology, 2010Co-Authors: Maria Pilar Carrera, Maria Jesus Ramírez-expósito, Maria Dolores Mayas, Maria Jesus García, Jose Manuel Martínez-martosAbstract:Angiotensin II in particular and/or the local renin–angiotensin system in general could have an important role in epithelial tissue growth and modelling; therefore, it is possible that it may be involved in breast cancer. In this sense, previous works of our group showed a predominating role of angiotensin II in tumoral tissue obtained from women with breast cancer. However, although classically angiotensin II has been considered the main effector peptide of the renin–angiotensin system cascade, several of its catabolism products such as angiotensin III and angiotensin IV also possess biological functions. These peptides are formed through the activity of several proteolytic regulatory enzymes of the aminopeptidase type, also called Angiotensinases. The aim of this work was to analyse several specific Angiotensinase activities involved in the renin–angiotensin system cascade in mammary tissue from control rats and from rats with mammary tumours induced by N -methyl-nitrosourea (NMU), which may reflect the functional status of their target peptides under the specific conditions brought about by the tumoural process. The results show that soluble and membrane-bound specific aspartyl aminopeptidase activities and membrane-bound glutamyl aminopeptidase activity increased in mammary tissue from NMU-treated animals and soluble aminopeptidase N and aminopeptidase B activities significantly decreased in mammary tissue from NMU-treated rats. These changes support the existence of a local mammary renin–angiotensin system and that this system and its putative functions in breast tissue could be altered by the tumour process, in which we suggest a predominant role of angiotensin III. All described data about the renin–angiotensin system in mammary tissue support the idea that it must be involved in normal breast tissue functions, and its disruption could be involved in one or more steps of the carcinogenesis process.
R. A. K. Stahl - One of the best experts on this subject based on the ideXlab platform.
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Angiotensinase A gene expression and enzyme activity in isolated glomeruli of diabetic rats
Diabetologia, 1996Co-Authors: F. Thaiss, G. Wolf, N. Assad, G. Zahner, R. A. K. StahlAbstract:One of the characteristics of early diabetic nephropathy is glomerular hyperfiltration and hyperperfusion. Many factors have been suggested to induce glomerular hyperperfusion among which are an increased production of vasodilatory prostanoids, an increased synthesis of nitric oxide, a reduced responsiveness of afferent glomerular arterioles to vasoconstrictor stimuli due to diabetic metabolic disturbances and a decreased receptor density for angiotensin II. It has been known for years that angiotensin II is formed locally due to the local activation of the renin angiotensin system. The local angiotensin II concentration, however, is not only regulated by the synthesis rate but also by the local degradation through activation of an aminopeptidase. The main finding of the present study was that the mRNA expression and activity of the angiotensin II degrading enzyme, Angiotensinase A, was increased twofold in diabetic rats at 5 weeks and that the increase in mRNA expression was suppressed by insulin therapy and short-term treatment with the angiotensin II antagonist saralasin, whereas Angiotensinase A enzyme activity was only reduced by saralasin and not by insulin. These results demonstrate that the angiotensin II degrading exopeptidase Angiotensinase A is activated in diabetic glomeruli. This increased activity may be an additional mechanism to explain glomerular hyperfiltration and hyperperfusion in early diabetic nephropathy.
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Glomerular Angiotensinase A in the rat: Increase of enzyme activity following renal ablation
Kidney International, 1990Co-Authors: Gunter Wolf, Jürgen E. Scherberich, Friedrich Thaiss, Wilhelm Schoeppe, R. A. K. StahlAbstract:Glomerular Angiotensinase A in the rat: Increase of enzyme activity following renal ablation. Angiotensinase A (aminopeptidase A; ATA) is an angiotensin II splitting exopeptidase, which is localized in endothelial and epithelial cells of the glomerular tuft. In order to investigate the influence of a reduction in renal mass on enzyme activity, ATA activity was measured in isolated rat glomeruli five and 14 weeks after 1-1/3 nephrectomy. Glomerular ATA activity in remnant kidneys increased significantly after five weeks following ablation compared with glomeruli of two kidney control rats (5.34 ± 4.02 vs. 1.71 ± 1.96mU /mg protein, P
Maria Pilar Carrera - One of the best experts on this subject based on the ideXlab platform.
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Mammary renin–angiotensin system-regulating aminopeptidase activities are modified in rats with breast cancer
Tumor Biology, 2010Co-Authors: Maria Pilar Carrera, Maria Jesus Ramírez-expósito, Maria Dolores Mayas, Maria Jesus García, Jose Manuel Martínez-martosAbstract:Angiotensin II in particular and/or the local renin–angiotensin system in general could have an important role in epithelial tissue growth and modelling; therefore, it is possible that it may be involved in breast cancer. In this sense, previous works of our group showed a predominating role of angiotensin II in tumoral tissue obtained from women with breast cancer. However, although classically angiotensin II has been considered the main effector peptide of the renin–angiotensin system cascade, several of its catabolism products such as angiotensin III and angiotensin IV also possess biological functions. These peptides are formed through the activity of several proteolytic regulatory enzymes of the aminopeptidase type, also called Angiotensinases. The aim of this work was to analyse several specific Angiotensinase activities involved in the renin–angiotensin system cascade in mammary tissue from control rats and from rats with mammary tumours induced by N -methyl-nitrosourea (NMU), which may reflect the functional status of their target peptides under the specific conditions brought about by the tumoural process. The results show that soluble and membrane-bound specific aspartyl aminopeptidase activities and membrane-bound glutamyl aminopeptidase activity increased in mammary tissue from NMU-treated animals and soluble aminopeptidase N and aminopeptidase B activities significantly decreased in mammary tissue from NMU-treated rats. These changes support the existence of a local mammary renin–angiotensin system and that this system and its putative functions in breast tissue could be altered by the tumour process, in which we suggest a predominant role of angiotensin III. All described data about the renin–angiotensin system in mammary tissue support the idea that it must be involved in normal breast tissue functions, and its disruption could be involved in one or more steps of the carcinogenesis process.