A 32-year-old man recovered completely from hypokalemic hypertension that had been caused by primary reninism after the ablation of an ectopic left testis, epididymis and ductus deferens. For several years, severe hyp...A 32-year-old man recovered completely from hypokalemic hypertension that had been caused by primary reninism after the ablation of an ectopic left testis, epididymis and ductus deferens. For several years, severe hypertension has been resistant to treatment, even the concurrent administration of up to seven antihypertensive agents. In this case, cryptorchidism was associated with an indirect inguinal hernia and an open peritoneo-vaginal process on both sides, aplasia of the posterior wall of the inguinal canal on the right side, an umbilical hernia, and a retroperitoneal tendrillar hemangioma. （Asian J Androl 2006 Mar; 8： 247-250）展开更多
BACKGROUND Primary hyperaldosteronism(PH)is considered to contribute to increased risk of developing type 2 diabetes mellitus(T2DM)and prediabetes.Both PH and DM are associated with increased risk for hypertension,car...BACKGROUND Primary hyperaldosteronism(PH)is considered to contribute to increased risk of developing type 2 diabetes mellitus(T2DM)and prediabetes.Both PH and DM are associated with increased risk for hypertension,cardiovascular diseases,and chronic kidney diseases.However,data on prevalence of T2DM and prediabetes in PH,and impact of T2DM and prediabetes on presentation and cardio renal complications in PH at presentation is sparse.AIM To determine the prevalence of T2DM and prediabetes in PH at diagnosis and impact on presentation and complications of PH.METHODS A retrospective cohort study was conducted in tertiary care settings in individuals with confirmed diagnosis of PH at presentation.Demographic variables,clinical presentations,duration and degree of hypertension,complications,laboratory parameters including sodium,potassium levels,plasma aldosterone concentration(PAC),plasma renin activity(PRA),and aldosterone to renin ratio(ARR)and cardio-renal parameters were collected.Comparison was done between three groups:PH with no DM(Group A)or with pre-diabetes(Group B)or with T2DM(Group C).P<0.05 was statistically significant.RESULTS Among 78 individuals with confirmed PH,62%had pre-diabetes or diabetes;with 37%having DM.Mean duration of T2DM was 5.97±4.7 years.The mean levels of glycaemic parameters among the group A vs B vs C individuals were fasting plasma glucose(mg/dL):87.9±6.5,105.4±9.02,130.6±21.1;post prandial plasma glucose(mg/dL):122.7±9.8,154.9±14,196.7±38.0;glycated haemoglobin(%)(5.3±0.2,5.9±0.2,7.5±0.6,P<0.05),respectively.There was no significant difference in the biochemical parameters(PAC,PRA,ARR,sodium,potassium levels),presentation and complications between the groups.Cardio renal parameters or degree and duration of hypertension were comparable between the groups.CONCLUSION Significant prevalence of T2DM and prediabetes in PH at diagnosis does not impact its presentation or complications.Early screening for undetected PH in T2DM and prediabetes subjects with hypertension may prevent complications.展开更多
BACKGROUND The initial trials on angiotensin II(AT II)administration indicated a high incidence of thrombocytopenia and thrombosis,as well as a positive correlation between hyperreninemia and response to the medicatio...BACKGROUND The initial trials on angiotensin II(AT II)administration indicated a high incidence of thrombocytopenia and thrombosis,as well as a positive correlation between hyperreninemia and response to the medication.CASE SUMMARY We describe a case of a patient presenting with catecholamine resistant septic shock,thrombocytopenia,deep vein thrombosis,and normal renin concentration who responded immediately to AT II treatment.We observed no worsening of thrombocytopenia and no progression of thrombosis or additional thromboses during treatment.CONCLUSION Our case underscores the need for individualized assessment of patients for potential therapy with AT II.展开更多
Background:Cytomegalovirus(CMV)reactivation is linked to a high mortality rate,especially among the elderly.Prior research suggests that renin-angiotensin system(RAS)inhibitors may influence both the onset and prognos...Background:Cytomegalovirus(CMV)reactivation is linked to a high mortality rate,especially among the elderly.Prior research suggests that renin-angiotensin system(RAS)inhibitors may influence both the onset and prognosis of pneumonia.This study aims to examine the causal relationship between RAS inhibitor use and the risk of CMV pneumonia using Mendelian randomization(MR)analysis.Methods:We conducted an analysis using data from two genome-wide association studies(GWAS)involving individuals of European ancestry.This dataset included individuals treated with RAS inhibitors and those with CMV pneumonia.We assessed the relationship between RAS inhibitor use and CMV pneumonia risk using the inverse variance weighted(IVW)method.The results were further evaluated for pleiotropy,heterogeneity,and robustness.Results:The Mendelian randomization(MR)analysis revealed a causal relationship between RAS inhibitor use and an increased risk of CMV pneumonia(IVW:odds ratio[OR]=2.73;95%confidence interval[CI]=1.11-6.73;P=0.028).Conclusions:Our finding indicate a positive causal relationship between the use of RAS inhibitors and the onset of CMV pneumonia.展开更多
Hepatic fibrosis is considered a common response to many chronic hepatic injuries. It is a multifunctional process that involves several cell types, cytokines, chemokines and growth factors leading to a disruption of ...Hepatic fibrosis is considered a common response to many chronic hepatic injuries. It is a multifunctional process that involves several cell types, cytokines, chemokines and growth factors leading to a disruption of homeostatic mechanisms that maintain the liver ecosystem. In spite of many studies regarding the development of fibrosis, the understanding of the pathogenesis remains obscure. The hepatic tissue remodeling process is highly complex, resulting from the balance between collagen degradation and synthesis. Among the many mediators that take part in this process, the components of the Renin angiotensin system （RAS） have progressively assumed an important role. Angiotensin （Ang） II acts as a profibrotic mediator and Ang-（1-7）, the newly recognized RAS component, appears to exert a counter-regulatory role in liver tissue. We briefly review the liver fibrosis process and current aspects of the RAS. This review also aims to discuss some experimental evidence regarding the participation of RAS mediators in the pathogenesis of liver fibrosis, focusing on the putative role of the ACE2-Ang-（1-7）- Mas receptor axis.展开更多
Diabetic nephropathy has been the cause of lot of morbidity and mortality in the diabetic population. The renin angiotensin system (RAS) is considered to be involved in most of the pathological processes that result i...Diabetic nephropathy has been the cause of lot of morbidity and mortality in the diabetic population. The renin angiotensin system (RAS) is considered to be involved in most of the pathological processes that result in diabetic nephropathy. This system has various subsystems which contribute to the disease pathology. One of these involves angiotensin II (Ang II) which shows increased activity during diabetic nephropathy. This causes hypertrophy of various renal cells and has a pressor effect on arteriolar smooth muscle resulting in increased vascular pressure. Ang II also induces inflammation, apoptosis, cell growth, migration and differentiation. Monocyte chemoattractant protein-1 production responsible for renal fibrosis is also regulated by RAS. Polymorphism of angiotensin converting enzyme (ACE) and Angiotensinogen has been shown to have effects on RAS. Available treatment modalities have proven effective in controlling the progression of nephropathy. Various drugs (based on antagonism of RAS) are currently in the market and others are still under trial. Amongst the approved drugs, ACE inhibitors and angiotensin receptor blockers (ARBs) are widely used in clinical practice. ARBs are shown to be superior to ACE inhibitors in terms of reducing proteinuria but the combined role of ARBs with ACE inhibitors in diabetic nephropathy is under debate.展开更多
Portal hypertension and bleeding from gastroesophageal varices is the major cause of morbidity and mortality in patients with cirrhosis. Portal hypertension is initiated by increased intrahepatic vascular resistance a...Portal hypertension and bleeding from gastroesophageal varices is the major cause of morbidity and mortality in patients with cirrhosis. Portal hypertension is initiated by increased intrahepatic vascular resistance and a hyperdynamic circulatory state. The latter is characterized by a high cardiac output, increased total blood volume and splanchnic vasodilatation, resulting in increased mesenteric blood flow. Pharmacological manipulation of cirrhotic portal hypertension targets both the splanchnic and hepatic vascular beds. Drugs such as angiotensin converting enzyme inhibitors and angiotensin Ⅱ type receptor 1 blockers, which target the components of the classical renin angiotensin system(RAS), are expected to reduce intrahepatic vascular tone by reducing extracellular matrix deposition and vasoactivity of contractile cells and thereby improve portal hypertension. However, these drugs have been shown to produce significant offtarget effects such as systemic hypotension and renal failure. Therefore, the current pharmacological mainstay in clinical practice to prevent variceal bleeding and improving patient survival by reducing portal pressure is non-selective-blockers(NSBBs). These NSBBs work by reducing cardiac output and splanchnic vasodilatation but most patients do not achieve an optimal therapeutic response and a significant proportion of patients are unable to tolerate these drugs.Although statins, used alone or in combination with NSBBs, have been shown to improve portal pressure and overall mortality in cirrhotic patients, further randomized clinical trials are warranted involving larger patient populations with clear clinical end points. On the other hand, recent findings from studies that have investigated the potential use of the blockers of the components of the alternate RAS provided compelling evidence that could lead to the development of drugs targeting the splanchnic vascular bed to inhibit splanchnic vasodilatation in portal hypertension. This review outlines the mechanisms related to the pathogenesis of portal hypertension and attempts to provide an update on currently available therapeutic approaches in the management of portal hypertension with special emphasis on how the alternate RAS could be manipulated in our search for development of safe, specific and effective novel therapies to treat portal hypertension in cirrhosis.展开更多
In the last three decades,the understanding of the renin angiotensin system(RAS)has been changed by the discoveries of functional local systems,novel biologically active peptides,additional specific receptors,alternat...In the last three decades,the understanding of the renin angiotensin system(RAS)has been changed by the discoveries of functional local systems,novel biologically active peptides,additional specific receptors,alternative pathways of angiotensin(Ang)?Ⅱ?generation,and new roles for enzymes and precursor components other than those in Ang?Ⅱ?synthesis.In this regard,the discovery that Ang-(1-7)opposes the pressor,proliferative,pro-fibrotic,and pro-inflammatory effects mediated by Ang?Ⅱ?has contributed to the realization that the RAS is composed of two axes.The first axis consists of the angiotensin-converting enzyme(ACE),with Ang?Ⅱ?as the end product,and the angiotensin type 1(AT1)receptor as the main effector mediating the biological actions of Ang?Ⅱ.The second axis results from ACE2-mediated hydrolysis of Ang?Ⅱ,leading to the production of Ang-(1-7),with the Mas receptor as the main effector conveying the vasodilatory,antiproliferative,anti-fibrotic,and anti-inflammatory effects of Ang-(1-7).Experimental and clinical studies have shown that both axes of the RAS may take part in the pathogenesis of liver diseases.In this manuscript,we summarize the current evidence regarding the role of RAS in hepatic cirrhosis and its complications,including hemodynamic changes and hepatorenal syndrome.The therapeutic potential of the modulation of RAS molecules in liver diseases is also discussed.展开更多
Objective To evaluate whether the clustering of risk factors, both environmental and genetic, increases the risk of essential hypertension （EH） and the accumulation of risk factors influences the blood pressure leve...Objective To evaluate whether the clustering of risk factors, both environmental and genetic, increases the risk of essential hypertension （EH） and the accumulation of risk factors influences the blood pressure level in normotensives. Methods On the basis of a prevalence survey, 501 subjects of Mongolian ethnicity （243 hypertensives and 258 normotensives） who were not related to each other were selected to conduct a case-control study. All subjects were interviewed with questionnaires and their blood specimens were collected. Renin gene insertion/deletion （I/D） polymorphism, a new genetic marker, was genotyped with PCR and polyacrylamide gel electrophoresis. Results Overweight, alcohol consumption, and renin gene I/D polymorphism were significant risk factors of EH （P〈0.05）. The odds ratios （OR） for the number of risk factors were 2.39 （95%CI： 0.98-6.74） for one risk factor, 5.03 （95%CI： 2.06-14.18） for two, and 6.09 （95%CI： 1.85-22.38） for three respectively after adjusting for age and sex. In normotensives, age- and sex-adjusted mean blood pressures increased with more accumulation of risk factors. However, there were no significant differences among the different blood pressure levels according to the number of risk factors （P〉0.05）. Conclusion Overweight, alcohol consumption, and renin gene I/D polymorphism are risk factors of EH in the Mongolian ethnic population of China. The accumulation of the risk factors causes a sharp increase of the risk of EH.展开更多
Over the past two decades considerable progress has been made in understanding the ototoxic effects and mechanisms underlying loop diuretics. As typical representative of loop diuretics ethacrynic acid or furosemide o...Over the past two decades considerable progress has been made in understanding the ototoxic effects and mechanisms underlying loop diuretics. As typical representative of loop diuretics ethacrynic acid or furosemide only induces temporary hearing loss, but rarely permanent deafness unless applied in severe acute or chronic renal failure or with other ototoxic drugs. Loop diuretic induce unique pathological changes in the cochlea such as formation of edematous spaces in the epithelium of the stria vascularis, which leads to rapid decrease of the endolymphatic potential and eventual loss of the cochlear microphonic potential, summating potential, and compound action potential. Loop diuretics interfere with strial adenylate cyclase and Nat/Kt-ATPase and inhibit the Na-K-2Cl cotransporter in the stria vascularis, however recent reports indicate that one of the earliest effects in vivo is to abolish blood flow in the vessels supplying the lateral wall. Since ethacrynic acid does not damage the stria vascularis in vitro, the changes in Nat/Kt-ATPase and Na-K-2Cl seen in vivo may be secondary effects results from strial ischemia and anoxia. Recent observations showing that renin is present in pericytes surrounding stria arterioles suggest that diuretics may induce local vasoconstriction by renin secretion and angiotensin formation. The tight junctions in the blood-cochlea barrier prevent toxic molecules and pathogens from entering cochlea, but when diuretics induce a transient ischemia, the barrier is temporarily disrupted allowing the entry of toxic chemicals or pathogens.展开更多
Objective. To investigate whether the polymorphisms in the angiotensin converting enzyme (ACE) gene and angiotensinogen (AGT) gene are associated with essential hypertension. Methods. A case-control study was carried ...Objective. To investigate whether the polymorphisms in the angiotensin converting enzyme (ACE) gene and angiotensinogen (AGT) gene are associated with essential hypertension. Methods. A case-control study was carried out using 103 hypertensive (HT) and 131 normotensive (NT) subjects. The insertion/deletion(I / D ) polymorphism of the ACE gene and the methionine→threo- nine variant at position 235 (M235T) of the AGT gene were determined by the polymerase chain reaction (PCR) technique and PCR/restriction fragment length polymorphism (PCR/RFLP) analysis, respective- ly. Results. The differences of D allele frequency and genotype distribution of the ACE gene between NT and HT groups were statistically significant (X^2=18.12, P<0. 005 ). The T235 allele frequency of the AGT gene was 69% in NT Chinese group (approximately 1. 38 to l. 64 fold that in Caucasians), and was greater in female HT than in NT (0. 82 vs 0. 72, X^2= 8. l, P<0. 025). A correlation between M235T molecular variant of the AGT gene and I/D molecular variant of ACE gene to hypertension was found. Cbeclusions. The possession of D allele of the ACE gene might be a marker for predisposition to hyper- tension. The T235 allele of the AGT gene was more common in Chinese than in Caucasians, and might contribute to the risk for hypertension in female Chinese.展开更多
Vitamin D deficiency has been indicated as a pandemicemerging public health problem. In addition to the well-known role on calcium-phosphorus homeostasis in thebone, vitamin D-mediated processes have been recentlyinve...Vitamin D deficiency has been indicated as a pandemicemerging public health problem. In addition to the well-known role on calcium-phosphorus homeostasis in thebone, vitamin D-mediated processes have been recentlyinvestigated on other diseases, such as infections, can-cer and cardiovascular diseases. Recently, both the dis-covery of paracrine actions of vitamin D(recognized as"local vitamin D system") and the link of vitamin D with renin-angiotensin-aldosterone system and the fibroblast growth factor 23/klotho pathways highlighted its ac-tive cardiovascular activity. Focusing on hypertension, this review summarizes the more recent experimental evidence involving the vitamin D system and deficiency in the cardiovascular pathophysiology. In particular, we updated the vascular synthesis/catabolism of vitamin D and its complex interactions between the various endocrine networks involved in the regulation of blood pressure in humans. On the other hand, the conflicting results emerged from the comparison between obser-vational and interventional studies emphasize the frag-mentary nature of our knowledge in the field of vitamin D and hypertension, strongly suggesting the need of further researches in this field.展开更多
BACKGROUND Neoangiogenesis is one of the key pathogenetic mechanisms in hepatocellular carcinoma (HCC). Modulation of the renin-angiotensin system (RAS) by angiotensin-converting enzyme inhibitors (ACE-Is) and angiote...BACKGROUND Neoangiogenesis is one of the key pathogenetic mechanisms in hepatocellular carcinoma (HCC). Modulation of the renin-angiotensin system (RAS) by angiotensin-converting enzyme inhibitors (ACE-Is) and angiotensin receptor blockers (ARBs) seems to be a possible adjuvant therapy for HCC, due to the antiangiogenic and anti-fibrogenic activity of these drugs. AIM To elucidate the role of ARBs and ACE-Is in HCC. METHODS We performed an electronic search of the literature using the most accessed online databases (PubMed, Cochrane library, Scopus and Web of Science), entering the query terms "angiotensin-converting enzyme inhibitors" OR "ACE inhibitors" OR "ACE-I" AND "hepatocarcinoma*" OR "hepatocellular carcinoma;moreover "angiotensin II type 1 receptor blockers" OR "ARBs" AND "hepatocarcinoma*" OR "hepatocellular carcinoma". Eligibility criteria were:(1) prospective or retrospective clinical studies;(2) epidemiological studies;and (3) experimental studies conducted in vivo or in vitro. Abstracts, conference papers, and reviews were excluded a priori. We limited our literature search to articles published in English, in peer-reviewed journals.RESULTS Thirty-one studies were selected. Three interventional studies showed that ACEIs had a significant protective effect on HCC recurrence only when used in combination with vitamin K or branched chain aminoacids, without a significant increase in overall survival. Of six retrospective observational studies, mainly focused on overall survival, only one demonstrated a prolonged survival in the ACE-Is group, whereas the two that also evaluated tumor recurrence showed conflicting results. All experimental studies displayed beneficial effects of RAS inhibitors on hepatocarcinogenesis. Numerous experimental studies, conducted either on animals and cell cultures, demonstrated the anti-angiogenetic and antifibrotic effect of ACE-Is and ARBs, thanks to the suppression of some cytokines such as vascular endothelial growth factor, hypoxia-inducible factor-1a, transforming growth factor-beta and tumor necrosis factor alpha. All or parts of these mechanisms were demonstrated in rodents developing fewer HCC and preneoplastic lesions after receiving such drugs. CONCLUSION In humans, RAS inhibitors - alone or in combination - significantly suppressed the cumulative HCC recurrence, without prolonging patient survival, but some limitations intrinsic to these studies prompt further investigations.展开更多
Renin angiotensin system （RAS） activation has a significant influence on renal disease progression. The classical angiotensin-converting enzyme （ACE）-angio-tensin Ⅱ （Ang Ⅱ）-Ang Ⅱ type 1 （AT1） axis is consid...Renin angiotensin system （RAS） activation has a significant influence on renal disease progression. The classical angiotensin-converting enzyme （ACE）-angio-tensin Ⅱ （Ang Ⅱ）-Ang Ⅱ type 1 （AT1） axis is considered to control the effects of RAS activation on renal disease. However, since its discovery in 2000 ACE2 has also been demonstrated to have a significant impact on the RAS. The synthesis and catabolism of Ang Ⅱ are regulated via a complex series of interactions, which involve ACE and ACE2. In the kidneys, ACE2 is expressed in the proximal tubules and less strongly in the glomeruli. The synthesis of inactive Ang 1-9 from Ang Ⅰ and the catabolism of Ang Ⅱ to produce Ang 1-7 are the main functions of ACE2. Ang 1-7 reduces vasoconstriction, water retention, salt intake, cell proliferation, and reactive oxygen stress, and also has a renoprotective effect. Thus, in the non-classical RAS the ACE2-Ang 1-7-Mas axis counteracts the ACE-Ang Ⅱ-AT1 axis. This review examines recent human and animal studies about renal ACE and ACE2.展开更多
文摘A 32-year-old man recovered completely from hypokalemic hypertension that had been caused by primary reninism after the ablation of an ectopic left testis, epididymis and ductus deferens. For several years, severe hypertension has been resistant to treatment, even the concurrent administration of up to seven antihypertensive agents. In this case, cryptorchidism was associated with an indirect inguinal hernia and an open peritoneo-vaginal process on both sides, aplasia of the posterior wall of the inguinal canal on the right side, an umbilical hernia, and a retroperitoneal tendrillar hemangioma. （Asian J Androl 2006 Mar; 8： 247-250）
文摘BACKGROUND Primary hyperaldosteronism(PH)is considered to contribute to increased risk of developing type 2 diabetes mellitus(T2DM)and prediabetes.Both PH and DM are associated with increased risk for hypertension,cardiovascular diseases,and chronic kidney diseases.However,data on prevalence of T2DM and prediabetes in PH,and impact of T2DM and prediabetes on presentation and cardio renal complications in PH at presentation is sparse.AIM To determine the prevalence of T2DM and prediabetes in PH at diagnosis and impact on presentation and complications of PH.METHODS A retrospective cohort study was conducted in tertiary care settings in individuals with confirmed diagnosis of PH at presentation.Demographic variables,clinical presentations,duration and degree of hypertension,complications,laboratory parameters including sodium,potassium levels,plasma aldosterone concentration(PAC),plasma renin activity(PRA),and aldosterone to renin ratio(ARR)and cardio-renal parameters were collected.Comparison was done between three groups:PH with no DM(Group A)or with pre-diabetes(Group B)or with T2DM(Group C).P<0.05 was statistically significant.RESULTS Among 78 individuals with confirmed PH,62%had pre-diabetes or diabetes;with 37%having DM.Mean duration of T2DM was 5.97±4.7 years.The mean levels of glycaemic parameters among the group A vs B vs C individuals were fasting plasma glucose(mg/dL):87.9±6.5,105.4±9.02,130.6±21.1;post prandial plasma glucose(mg/dL):122.7±9.8,154.9±14,196.7±38.0;glycated haemoglobin(%)(5.3±0.2,5.9±0.2,7.5±0.6,P<0.05),respectively.There was no significant difference in the biochemical parameters(PAC,PRA,ARR,sodium,potassium levels),presentation and complications between the groups.Cardio renal parameters or degree and duration of hypertension were comparable between the groups.CONCLUSION Significant prevalence of T2DM and prediabetes in PH at diagnosis does not impact its presentation or complications.Early screening for undetected PH in T2DM and prediabetes subjects with hypertension may prevent complications.
文摘BACKGROUND The initial trials on angiotensin II(AT II)administration indicated a high incidence of thrombocytopenia and thrombosis,as well as a positive correlation between hyperreninemia and response to the medication.CASE SUMMARY We describe a case of a patient presenting with catecholamine resistant septic shock,thrombocytopenia,deep vein thrombosis,and normal renin concentration who responded immediately to AT II treatment.We observed no worsening of thrombocytopenia and no progression of thrombosis or additional thromboses during treatment.CONCLUSION Our case underscores the need for individualized assessment of patients for potential therapy with AT II.
文摘Background:Cytomegalovirus(CMV)reactivation is linked to a high mortality rate,especially among the elderly.Prior research suggests that renin-angiotensin system(RAS)inhibitors may influence both the onset and prognosis of pneumonia.This study aims to examine the causal relationship between RAS inhibitor use and the risk of CMV pneumonia using Mendelian randomization(MR)analysis.Methods:We conducted an analysis using data from two genome-wide association studies(GWAS)involving individuals of European ancestry.This dataset included individuals treated with RAS inhibitors and those with CMV pneumonia.We assessed the relationship between RAS inhibitor use and CMV pneumonia risk using the inverse variance weighted(IVW)method.The results were further evaluated for pleiotropy,heterogeneity,and robustness.Results:The Mendelian randomization(MR)analysis revealed a causal relationship between RAS inhibitor use and an increased risk of CMV pneumonia(IVW:odds ratio[OR]=2.73;95%confidence interval[CI]=1.11-6.73;P=0.028).Conclusions:Our finding indicate a positive causal relationship between the use of RAS inhibitors and the onset of CMV pneumonia.
文摘Hepatic fibrosis is considered a common response to many chronic hepatic injuries. It is a multifunctional process that involves several cell types, cytokines, chemokines and growth factors leading to a disruption of homeostatic mechanisms that maintain the liver ecosystem. In spite of many studies regarding the development of fibrosis, the understanding of the pathogenesis remains obscure. The hepatic tissue remodeling process is highly complex, resulting from the balance between collagen degradation and synthesis. Among the many mediators that take part in this process, the components of the Renin angiotensin system （RAS） have progressively assumed an important role. Angiotensin （Ang） II acts as a profibrotic mediator and Ang-（1-7）, the newly recognized RAS component, appears to exert a counter-regulatory role in liver tissue. We briefly review the liver fibrosis process and current aspects of the RAS. This review also aims to discuss some experimental evidence regarding the participation of RAS mediators in the pathogenesis of liver fibrosis, focusing on the putative role of the ACE2-Ang-（1-7）- Mas receptor axis.
文摘Diabetic nephropathy has been the cause of lot of morbidity and mortality in the diabetic population. The renin angiotensin system (RAS) is considered to be involved in most of the pathological processes that result in diabetic nephropathy. This system has various subsystems which contribute to the disease pathology. One of these involves angiotensin II (Ang II) which shows increased activity during diabetic nephropathy. This causes hypertrophy of various renal cells and has a pressor effect on arteriolar smooth muscle resulting in increased vascular pressure. Ang II also induces inflammation, apoptosis, cell growth, migration and differentiation. Monocyte chemoattractant protein-1 production responsible for renal fibrosis is also regulated by RAS. Polymorphism of angiotensin converting enzyme (ACE) and Angiotensinogen has been shown to have effects on RAS. Available treatment modalities have proven effective in controlling the progression of nephropathy. Various drugs (based on antagonism of RAS) are currently in the market and others are still under trial. Amongst the approved drugs, ACE inhibitors and angiotensin receptor blockers (ARBs) are widely used in clinical practice. ARBs are shown to be superior to ACE inhibitors in terms of reducing proteinuria but the combined role of ARBs with ACE inhibitors in diabetic nephropathy is under debate.
基金Supported by National Health and Medical Research Council (NHMRC) of Australia Project Grants,No. APP1124125。
文摘Portal hypertension and bleeding from gastroesophageal varices is the major cause of morbidity and mortality in patients with cirrhosis. Portal hypertension is initiated by increased intrahepatic vascular resistance and a hyperdynamic circulatory state. The latter is characterized by a high cardiac output, increased total blood volume and splanchnic vasodilatation, resulting in increased mesenteric blood flow. Pharmacological manipulation of cirrhotic portal hypertension targets both the splanchnic and hepatic vascular beds. Drugs such as angiotensin converting enzyme inhibitors and angiotensin Ⅱ type receptor 1 blockers, which target the components of the classical renin angiotensin system(RAS), are expected to reduce intrahepatic vascular tone by reducing extracellular matrix deposition and vasoactivity of contractile cells and thereby improve portal hypertension. However, these drugs have been shown to produce significant offtarget effects such as systemic hypotension and renal failure. Therefore, the current pharmacological mainstay in clinical practice to prevent variceal bleeding and improving patient survival by reducing portal pressure is non-selective-blockers(NSBBs). These NSBBs work by reducing cardiac output and splanchnic vasodilatation but most patients do not achieve an optimal therapeutic response and a significant proportion of patients are unable to tolerate these drugs.Although statins, used alone or in combination with NSBBs, have been shown to improve portal pressure and overall mortality in cirrhotic patients, further randomized clinical trials are warranted involving larger patient populations with clear clinical end points. On the other hand, recent findings from studies that have investigated the potential use of the blockers of the components of the alternate RAS provided compelling evidence that could lead to the development of drugs targeting the splanchnic vascular bed to inhibit splanchnic vasodilatation in portal hypertension. This review outlines the mechanisms related to the pathogenesis of portal hypertension and attempts to provide an update on currently available therapeutic approaches in the management of portal hypertension with special emphasis on how the alternate RAS could be manipulated in our search for development of safe, specific and effective novel therapies to treat portal hypertension in cirrhosis.
基金Supported by CNPq,No.460334/2014-0 and FAPEMIG,No.CDS-PPM-00555-15
文摘In the last three decades,the understanding of the renin angiotensin system(RAS)has been changed by the discoveries of functional local systems,novel biologically active peptides,additional specific receptors,alternative pathways of angiotensin(Ang)?Ⅱ?generation,and new roles for enzymes and precursor components other than those in Ang?Ⅱ?synthesis.In this regard,the discovery that Ang-(1-7)opposes the pressor,proliferative,pro-fibrotic,and pro-inflammatory effects mediated by Ang?Ⅱ?has contributed to the realization that the RAS is composed of two axes.The first axis consists of the angiotensin-converting enzyme(ACE),with Ang?Ⅱ?as the end product,and the angiotensin type 1(AT1)receptor as the main effector mediating the biological actions of Ang?Ⅱ.The second axis results from ACE2-mediated hydrolysis of Ang?Ⅱ,leading to the production of Ang-(1-7),with the Mas receptor as the main effector conveying the vasodilatory,antiproliferative,anti-fibrotic,and anti-inflammatory effects of Ang-(1-7).Experimental and clinical studies have shown that both axes of the RAS may take part in the pathogenesis of liver diseases.In this manuscript,we summarize the current evidence regarding the role of RAS in hepatic cirrhosis and its complications,including hemodynamic changes and hepatorenal syndrome.The therapeutic potential of the modulation of RAS molecules in liver diseases is also discussed.
基金This study was supported by the National Natural Sciences Foundation of China (Grant No. 30271149)Beijing Municipal NaturalSciences Foundation (No. 7001004)China Medical Board in New York (No. 96-657).
文摘Objective To evaluate whether the clustering of risk factors, both environmental and genetic, increases the risk of essential hypertension （EH） and the accumulation of risk factors influences the blood pressure level in normotensives. Methods On the basis of a prevalence survey, 501 subjects of Mongolian ethnicity （243 hypertensives and 258 normotensives） who were not related to each other were selected to conduct a case-control study. All subjects were interviewed with questionnaires and their blood specimens were collected. Renin gene insertion/deletion （I/D） polymorphism, a new genetic marker, was genotyped with PCR and polyacrylamide gel electrophoresis. Results Overweight, alcohol consumption, and renin gene I/D polymorphism were significant risk factors of EH （P〈0.05）. The odds ratios （OR） for the number of risk factors were 2.39 （95%CI： 0.98-6.74） for one risk factor, 5.03 （95%CI： 2.06-14.18） for two, and 6.09 （95%CI： 1.85-22.38） for three respectively after adjusting for age and sex. In normotensives, age- and sex-adjusted mean blood pressures increased with more accumulation of risk factors. However, there were no significant differences among the different blood pressure levels according to the number of risk factors （P〉0.05）. Conclusion Overweight, alcohol consumption, and renin gene I/D polymorphism are risk factors of EH in the Mongolian ethnic population of China. The accumulation of the risk factors causes a sharp increase of the risk of EH.
基金supported in part by a grant from National Natural Science Foundation of China 81470706a grant from Guangdong Natural Science Foundation No 2015A030313180
文摘Over the past two decades considerable progress has been made in understanding the ototoxic effects and mechanisms underlying loop diuretics. As typical representative of loop diuretics ethacrynic acid or furosemide only induces temporary hearing loss, but rarely permanent deafness unless applied in severe acute or chronic renal failure or with other ototoxic drugs. Loop diuretic induce unique pathological changes in the cochlea such as formation of edematous spaces in the epithelium of the stria vascularis, which leads to rapid decrease of the endolymphatic potential and eventual loss of the cochlear microphonic potential, summating potential, and compound action potential. Loop diuretics interfere with strial adenylate cyclase and Nat/Kt-ATPase and inhibit the Na-K-2Cl cotransporter in the stria vascularis, however recent reports indicate that one of the earliest effects in vivo is to abolish blood flow in the vessels supplying the lateral wall. Since ethacrynic acid does not damage the stria vascularis in vitro, the changes in Nat/Kt-ATPase and Na-K-2Cl seen in vivo may be secondary effects results from strial ischemia and anoxia. Recent observations showing that renin is present in pericytes surrounding stria arterioles suggest that diuretics may induce local vasoconstriction by renin secretion and angiotensin formation. The tight junctions in the blood-cochlea barrier prevent toxic molecules and pathogens from entering cochlea, but when diuretics induce a transient ischemia, the barrier is temporarily disrupted allowing the entry of toxic chemicals or pathogens.
基金National Natural Sciences Foundation of China! (39470630 )
文摘Objective. To investigate whether the polymorphisms in the angiotensin converting enzyme (ACE) gene and angiotensinogen (AGT) gene are associated with essential hypertension. Methods. A case-control study was carried out using 103 hypertensive (HT) and 131 normotensive (NT) subjects. The insertion/deletion(I / D ) polymorphism of the ACE gene and the methionine→threo- nine variant at position 235 (M235T) of the AGT gene were determined by the polymerase chain reaction (PCR) technique and PCR/restriction fragment length polymorphism (PCR/RFLP) analysis, respective- ly. Results. The differences of D allele frequency and genotype distribution of the ACE gene between NT and HT groups were statistically significant (X^2=18.12, P<0. 005 ). The T235 allele frequency of the AGT gene was 69% in NT Chinese group (approximately 1. 38 to l. 64 fold that in Caucasians), and was greater in female HT than in NT (0. 82 vs 0. 72, X^2= 8. l, P<0. 025). A correlation between M235T molecular variant of the AGT gene and I/D molecular variant of ACE gene to hypertension was found. Cbeclusions. The possession of D allele of the ACE gene might be a marker for predisposition to hyper- tension. The T235 allele of the AGT gene was more common in Chinese than in Caucasians, and might contribute to the risk for hypertension in female Chinese.
基金Supported by European Commission(FP7-INNOVATION I HEALTH-F2-2013-602114Athero-B-Cell:Targeting and exploiting B cell function for treatment in cardiovascular disease)to Dr.F Mach+3 种基金Swiss National Science Foundation Grants to Dr.F Mach,No.#310030_118245Swiss National Science Foundation Grants to Dr.N Vuilleumier,No.#310030_140736and Swiss National Science Foundation Grants to Dr.F Montecucco,No.#32003B_134963/1the Novartis Foundation and the Foundation"Gustave and Simone Prévot"to Dr.F Montecucco
文摘Vitamin D deficiency has been indicated as a pandemicemerging public health problem. In addition to the well-known role on calcium-phosphorus homeostasis in thebone, vitamin D-mediated processes have been recentlyinvestigated on other diseases, such as infections, can-cer and cardiovascular diseases. Recently, both the dis-covery of paracrine actions of vitamin D(recognized as"local vitamin D system") and the link of vitamin D with renin-angiotensin-aldosterone system and the fibroblast growth factor 23/klotho pathways highlighted its ac-tive cardiovascular activity. Focusing on hypertension, this review summarizes the more recent experimental evidence involving the vitamin D system and deficiency in the cardiovascular pathophysiology. In particular, we updated the vascular synthesis/catabolism of vitamin D and its complex interactions between the various endocrine networks involved in the regulation of blood pressure in humans. On the other hand, the conflicting results emerged from the comparison between obser-vational and interventional studies emphasize the frag-mentary nature of our knowledge in the field of vitamin D and hypertension, strongly suggesting the need of further researches in this field.
文摘BACKGROUND Neoangiogenesis is one of the key pathogenetic mechanisms in hepatocellular carcinoma (HCC). Modulation of the renin-angiotensin system (RAS) by angiotensin-converting enzyme inhibitors (ACE-Is) and angiotensin receptor blockers (ARBs) seems to be a possible adjuvant therapy for HCC, due to the antiangiogenic and anti-fibrogenic activity of these drugs. AIM To elucidate the role of ARBs and ACE-Is in HCC. METHODS We performed an electronic search of the literature using the most accessed online databases (PubMed, Cochrane library, Scopus and Web of Science), entering the query terms "angiotensin-converting enzyme inhibitors" OR "ACE inhibitors" OR "ACE-I" AND "hepatocarcinoma*" OR "hepatocellular carcinoma;moreover "angiotensin II type 1 receptor blockers" OR "ARBs" AND "hepatocarcinoma*" OR "hepatocellular carcinoma". Eligibility criteria were:(1) prospective or retrospective clinical studies;(2) epidemiological studies;and (3) experimental studies conducted in vivo or in vitro. Abstracts, conference papers, and reviews were excluded a priori. We limited our literature search to articles published in English, in peer-reviewed journals.RESULTS Thirty-one studies were selected. Three interventional studies showed that ACEIs had a significant protective effect on HCC recurrence only when used in combination with vitamin K or branched chain aminoacids, without a significant increase in overall survival. Of six retrospective observational studies, mainly focused on overall survival, only one demonstrated a prolonged survival in the ACE-Is group, whereas the two that also evaluated tumor recurrence showed conflicting results. All experimental studies displayed beneficial effects of RAS inhibitors on hepatocarcinogenesis. Numerous experimental studies, conducted either on animals and cell cultures, demonstrated the anti-angiogenetic and antifibrotic effect of ACE-Is and ARBs, thanks to the suppression of some cytokines such as vascular endothelial growth factor, hypoxia-inducible factor-1a, transforming growth factor-beta and tumor necrosis factor alpha. All or parts of these mechanisms were demonstrated in rodents developing fewer HCC and preneoplastic lesions after receiving such drugs. CONCLUSION In humans, RAS inhibitors - alone or in combination - significantly suppressed the cumulative HCC recurrence, without prolonging patient survival, but some limitations intrinsic to these studies prompt further investigations.
基金Supported by The Toho University School of Medicine Research Foundation
文摘Renin angiotensin system （RAS） activation has a significant influence on renal disease progression. The classical angiotensin-converting enzyme （ACE）-angio-tensin Ⅱ （Ang Ⅱ）-Ang Ⅱ type 1 （AT1） axis is considered to control the effects of RAS activation on renal disease. However, since its discovery in 2000 ACE2 has also been demonstrated to have a significant impact on the RAS. The synthesis and catabolism of Ang Ⅱ are regulated via a complex series of interactions, which involve ACE and ACE2. In the kidneys, ACE2 is expressed in the proximal tubules and less strongly in the glomeruli. The synthesis of inactive Ang 1-9 from Ang Ⅰ and the catabolism of Ang Ⅱ to produce Ang 1-7 are the main functions of ACE2. Ang 1-7 reduces vasoconstriction, water retention, salt intake, cell proliferation, and reactive oxygen stress, and also has a renoprotective effect. Thus, in the non-classical RAS the ACE2-Ang 1-7-Mas axis counteracts the ACE-Ang Ⅱ-AT1 axis. This review examines recent human and animal studies about renal ACE and ACE2.
