Renin-Angiotensin System and Sex Differences in COVID-19: A Critical Assessment.

The current epidemic of corona virus disease (COVID-19) has resulted in an immense health burden that became the third leading cause of death and potentially contributed to a decline in life expectancy in the United States. The severe acute respiratory syndrome-related coronavirus-2 binds to the surface-bound peptidase angiotensin-converting enzyme 2 (ACE2, EC 3.4.17.23) leading to tissue infection and viral replication. ACE2 is an important enzymatic component of the renin-angiotensin system (RAS) expressed in the lung and other organs. The peptidase regulates the levels of the peptide hormones Ang II and Ang-(1-7), which have distinct and opposing actions to one another, as well as other cardiovascular peptides. A potential consequence of severe acute respiratory syndrome-related coronavirus-2 infection is reduced ACE2 activity by internalization of the viral-ACE2 complex and subsequent activation of the RAS (higher ratio of Ang II:Ang-[1-7]) that may exacerbate the acute inflammatory events in COVID-19 patients and possibly contribute to the effects of long COVID-19. Moreover, COVID-19 patients present with an array of autoantibodies to various components of the RAS including the peptide Ang II, the enzyme ACE2, and the AT1 AT2 and Mas receptors. Greater disease severity is also evident in male COVID-19 patients, which may reflect underlying sex differences in the regulation of the 2 distinct functional arms of the RAS. The current review provides a critical evaluation of the evidence for an activated RAS in COVID-19 subjects and whether this system contributes to the greater severity of severe acute respiratory syndrome-related coronavirus-2 infection in males as compared with females.

The role of angiotensin I converting enzyme insertion/deletion polymorphism in the severity and outcomes of COVID-19 patients.

The pandemic of coronavirus disease in 2019 has led to a global crisis. COVID-19 shows distinct clinical manifestations of the severity of symptoms. Numerous patients with no associated risk factors demonstrate acute respiratory distress syndrome (ARDS). The role of genetic factors in determining the severity and outcome of the disease remains unresolved. The purpose of this study was to see if a correlation exists between Angiotensin I Converting Enzyme (ACE) insertion/deletion (I/D) polymorphism and the severity of COVID-19 patients' symptoms. 120 COVID-19 patients admitted to Masih Daneshvari Hospital in Tehran with their consent to participate entered the study. Based on the World Health Organization classification, patients were divided into moderate and severe groups, which were primarily affected by O2 saturation levels. The effects of the patients' ACE insertion/deletion polymorphism, background disease, Angiotensin receptor blocker (ARB) drug consumption, and demographic parameters on the severity risk were calculated statistically. The ACE D allele was associated with an increased risk of disease severity (OR = 6.766, p = 0.012), but had no effect on mortality.

Targeting whole body metabolism and mitochondrial bioenergetics in the drug development for Alzheimer's disease.

Aging is by far the most prominent risk factor for Alzheimer's disease (AD), and both aging and AD are associated with apparent metabolic alterations. As developing effective therapeutic interventions to treat AD is clearly in urgent need, the impact of modulating whole-body and intracellular metabolism in preclinical models and in human patients, on disease pathogenesis, have been explored. There is also an increasing awareness of differential risk and potential targeting strategies related to biological sex, microbiome, and circadian regulation. As a major part of intracellular metabolism, mitochondrial bioenergetics, mitochondrial quality-control mechanisms, and mitochondria-linked inflammatory responses have been considered for AD therapeutic interventions. This review summarizes and highlights these efforts.

Targeting whole body metabolism and mitochondrial bioenergetics in the drug development for Alzheimer's disease

Aging is by far the most prominent risk factor for Alzheimer's disease (AD), and both aging and AD are associated with apparent metabolic alterations. As developing effective therapeutic interventions to treat AD is clearly in urgent need, the impact of modulating whole-body and intracellular metabolism in preclinical models and in human patients, on disease pathogenesis, have been explored. There is also an increasing awareness of differential risk and potential targeting strategies related to biological sex, microbiome, and circadian regulation. As a major part of intracellular metabolism, mitochondrial bioenergetics, mitochondrial quality-control mechanisms, and mitochondria-linked inflammatory responses have been considered for AD therapeutic interventions. This review summarizes and highlights these efforts.

Aristolochic Acid Induces Chronic Kidney Disease in ACE Knockout Mice.

BACKGROUND: Aristolochic acid I (AAI) is an extract from Chinese herbs that causes progressive interstitial nephritis. The aim of this research is to know whether chymases play the crucial role in AAI-induced nephropathy. METHODS: The mice were treated with AAI via intraperitoneal injection and the accumulated AAI dosages are 30 mg/kg of body weight for two, four, six, and eight weeks. The animals were sacrificed after another two or four weeks for nephropathy development. Collection of blood, urine, and kidney samples for the further biochemical analysis, hematoxylin-eosin (H and E) and Masson's trichrome stained to detected pathologic, and MMP2 and MMP9 activity assays. RESULTS: After the treatment of AAI, of the mice, their body weights were decreased (P < 0.01), and concentration of creatinine and blood urea nitrogen (BUN) in serum (P < 0.01) and urine collection were increased (P < 0.01). In the renal tissue sections, high amount of inflammatory cells were found by H and E stain, and increased fibrosis in renal interstitial tissue were observed by Masson's trichrome stain. In mice kidney tissue, significantly increased chymase activity after treatment of AAI was found (P < 0.01), but ACE activity did not show significant changes. In ACE KO mice, increased MMP2 and decreased MMP9 activity were found in the AAI-treated mice compared with AAI-untreated control (P < 0.01). CONCLUSIONS: Moreover, it was also observed that the deficiency of ACE would accelerate the disease development of AAI-induced nephropathy. These results may help to know more information about the role of AAI-induced chronic kidney disease and can be applied in developing new drug targets for nephropathy.

Levels of angiotensin-converting enzyme 1 and 2 in serum and urine of children with Sickle Cell Disease / Níveis de enzima conversora da angiotensina 1 e 2 no soro e na urina de crianças com Doença Falciforme

Abstract Introduction: Sickle cell nephropathy begins in childhood and presents early increases in glomerular filtration, which, over the long term, can lead to chronic renal failure. Several diseases have increased circulating and urinary angiotensin-converting enzyme (ACE) activity, but there is little information about changes in ACEs activity in children with sickle cell disease (SCD). Objective: We examined circulating and urinary ACE 1 activity in children with SCD. Methods: This cross-sectional study compared children who were carriers of SCD with children who comprised a control group (CG). Serum and urinary activities of ACE were evaluated, as were biochemical factors, urinary album/creatinine rates, and estimated glomerular filtration rate. Results: Urinary ACE activity was significantly higher in patients with SCD than in healthy children (median 0.01; range 0.00-0.07 vs median 0.00; range 0.00-0.01 mU/mL·creatinine, p < 0.001. No significant difference in serum ACE activities between the SCD and CG groups was observed (median 32.25; range 16.2-59.3 vs median 40.9; range 18.0-53.4) mU/m`L·creatinine, p < 0.05. Conclusion: Our data revealed a high urinary ACE 1 activity, different than plasmatic level, in SCD patients suggesting a dissociation between the intrarenal and systemic RAAS. The increase of urinary ACE 1 activity in SCD patients suggests higher levels of Ang II with a predominance of classical RAAS axis, that can induce kidney damage.

Resumo Introdução: A nefropatia falciforme começa na infância e apresenta aumentos precoces na filtração glomerular, que, em longo prazo, podem levar à insuficiência renal crônica. Várias doenças têm aumentado a atividade da enzima conversora da angiotensina (ECA) urinária e circulante, mas há pouca informação sobre alterações na atividade das ECAs em crianças com doença falciforme (DF). Objetivo: Examinamos a atividade da ECA-1 circulante e urinária em crianças com DF. Métodos: Este estudo transversal comparou crianças que eram portadoras de DF com crianças que compunham um Grupo Controle (GC). As atividades séricas e urinárias da ECA foram avaliadas, assim como os fatores bioquímicos, a relação albumina/creatinina urinária e a taxa de filtração glomerular estimada. Resultados: A atividade urinária da ECA foi significativamente maior em pacientes com DF do que em crianças saudáveis (mediana 0,01; intervalo 0,00-0,07 vs mediana 0,00; intervalo 0,00-0,01 mU/mL·creatinina, p < 0,001. Não foi observada diferença significativa nas atividades séricas da ECA entre os grupos DF e GC (mediana 32,25; intervalo 16,2-59,3 vs mediana 40,9; intervalo 18,0-53,4) mU/mL·creatinina, p < 0,05. Conclusão: Nossos dados revelaram uma alta atividade urinária da ECA-1, diferente do nível plasmático, em pacientes com DF, sugerindo uma dissociação entre o Sistema Renina Angiotensina Aldosterona (SRAA) intra-renal e sistêmico. O aumento da atividade urinária da ECA-1 em pacientes com DF sugere níveis mais elevados de Ang II com predominância do eixo clássico do SRAA, que pode induzir lesão renal.

Expression of ACE2 in the Intact and Acutely Injured Kidney.

Background: The actions of angiotensin-converting enzyme 2 (ACE2) oppose those of the renin-angiotensin-aldosterone system. ACE2 may be a cytoprotectant in some tissues. This study examined ACE2 expression in models of AKI. Methods: ACE2 mRNA and protein expression and ACE2 activity were assessed in murine ischemic AKI. Renal ACE2 mRNA expression was evaluated in LPS-induced AKI in wild-type (C57BL/6J) mice, in heme oxygenase-1+/+ and heme oxygenase-1-/- mice, and after unilateral ureteral obstruction (UUO) in wild-type mice. The effect of sex and age on renal ACE2 protein expression was also assessed. Results: In ischemic AKI, ACE2 mRNA and protein expression and ACE2 activity were reduced as compared with such indices in the intact kidney. In ischemic AKI, ACE2, which, in health, is prominently expressed in the tubular epithelium, especially proximal tubules, is decreased in expression in these segments. Decreased ACE2 expression in AKI did not reflect reduced GFR, because ACE2 mRNA expression was unaltered after UUO. LPS induced renal ACE2 mRNA expression in wild-type mice, but this effect did not occur in heme oxygenase-1-deficient mice. In ischemic and LPS-induced AKI, renal expression of the Mas receptor was increased. In the intact kidney, renal ACE2 protein expression decreased in female mice as compared with male mice, but was unaltered with age. Conclusion: We conclude that renal ACE2 expression is decreased in ischemic AKI, characterized by decreased GFR and abundant cell death, but is upregulated in LPS-induced AKI, an effect requiring heme oxygenase-1. Determining the significance of ACE2 expression in experimental AKI merits further study. We suggest that understanding the mechanism underlying ACE2 downregulation in AKI may offer insights relevant to COVID-19: ACE2 expression is downregulated after ACE2 mediates SARS-CoV-2 cellular entry; such downregulation is proinflammatory; and AKI commonly occurs and determines outcomes in COVID-19.

Upregulation of the angiotensin-converting enzyme 2-angiotensin-(1-7)-Mas receptor axis by a combination of Yinyanghuo (Herba Epimedii Brevicornus) and Cheqianzi (Semen Plantaginis) improves erectile function in spontaneously hypertensive rats.

OBJECTIVE: To evaluate the effects of a combination of Yinyanghuo (Herba Epimedii Brevicornus) (HEB) and Cheqianzi (Semen Plantaginis) (SP) on erectile dysfunction caused by essential hypertension in spontaneously hypertensive rats (SHRs), and to elucidate the role of the angiotensin-converting enzyme 2-angiotensin-(1-7)-Mas receptor (ACE2/Ang [1-7]/Mas receptor) axis in this process. METHODS: A total of 24 SHRs were randomly assigned to three groups: SHR-control, low-dose (12.5 g/kg) and high-dose (25 g/kg) HEB+SP (HEBSP). Eight Wistar-Kyoto rats were used as normal controls. HEBSP was administered by oral gavage for 28 d. Erectile function was measured once a week using the Heaton test. After 4 weeks of treatment, the corpus cavernosum was harvested from each rat to measure nitric oxide (NO), nitric oxide synthase (eNOS) and Ang (1-7) levels, as well as ACE2, Mas receptor and neuronal nitric oxide synthase (nNOS) protein expression. RESULTS: After 4 weeks of treatment, HEBSP significantly increased erectile function in the treated group compared with SHR-control group (P < 0.01). Additionally, HEBSP treatment significantly increased cavernosal levels of Ang (1-7), eNOS and NO. Moreover, HEBSP significantly elevated the expression levels of ACE2, Mas receptor and nNOS. These beneficial effects were elevated in the high-dose HEBSP group. CONCLUSION: HEBSP improved erectile function in SHRs by upregulating the ACE2/Ang (1-7)/Mas receptor axis, eNOS and nNOS pathways.

Comparative Efficacy and Safety of BP-Lowering Pharmacotherapy in Patients Undergoing Maintenance Dialysis: A Network Meta-Analysis of Randomized, Controlled Trials.

BACKGROUND AND OBJECTIVES: Elevated BP is an important risk factor for cardiovascular disease, with a prevalence of over 80% in patients undergoing maintenance dialysis. We assessed the comparative BP-lowering efficacy and the safety of BP-lowering drugs in patients undergoing maintenance dialysis. DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS: We performed a frequentist random effects network meta-analysis of randomized, controlled trials evaluating BP-lowering agents in adult patients undergoing maintenance dialysis. Electronic databases (CENTRAL, MEDLINE, and Embase) were systematically searched (up to August 2018) for relevant trials. The main outcome was systolic BP reduction. RESULTS: Forty trials (4283 participants) met our inclusion criteria. Angiotensin-converting enzyme inhibitors, ß-blockers, calcium-channel blockers, and aldosterone antagonists lowered systolic BP to a greater extent than placebo, with effect sizes ranging from -10.8 mm Hg (95% confidence interval, -14.8 to -6.7 mm Hg) for the aldosterone antagonists to -4.3 mm Hg (95% confidence interval, -7.2 to -1.5 mm Hg) for angiotensin-converting enzyme inhibitors. Aldosterone antagonists and ß-blockers were superior to angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, calcium-channel blockers, and renin inhibitors at lowering systolic BP. Compared with angiotensin-converting enzyme inhibitors, aldosterone antagonists and ß-blockers lowered systolic BP by 6.4 mm Hg (95% confidence interval, -11.4 to -1.4 mm Hg) and 4.4 mm Hg (95% confidence interval, -7.4 to -1.3 mm Hg), respectively. Systolic BP reduction was not different with angiotensin receptor blockers, α-blockers, and calcium-channel blockers compared with angiotensin-converting enzyme inhibitors. Renin inhibitors were less effective. Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and aldosterone antagonists incurred risks of drug discontinuation due to adverse events and hypotension. CONCLUSIONS: BP-lowering agents significantly reduced systolic BP in patients undergoing maintenance dialysis. ß-Blockers and aldosterone antagonists may confer larger reductions, although treatment with aldosterone antagonists may be limited by adverse events.

Degradation of thymic humoral factor γ2 in human, rat and mouse blood: An experimental and theoretical study.

The degradation of the immunomodulatory octapeptide, thymic humoral factor γ2 (THF-γ2, thymoctonan) has been studied in whole blood samples from human, rat and mouse. The peptide, Leu-Glu-Asp-Gly-Pro-Lys-Phe-Leu, was shown to be rapidly degraded by peptidases. The half-life of the intact peptide was less than 6 min at 37 °C in blood from the three species tested. The main fragments formed from THF-γ2 were found to be Glu-Asp-Gly-Pro-Lys-Phe-Leu (2-8), Asp-Gly-Pro-Lys-Phe-Leu (3-8) and Glu-Asp-Gly-Pro-Lys (2-6) in human and in rat blood and 2-8 and 2-6 in mouse blood. Analysis of the time course of degradation revealed a sequential removal of single amino acids from the N-terminus (aminopeptidase activities) in a process that was apparently unable to cleave the Gly-Pro bond (positions 4-5 in the peptide) together with an independent cleavage of the Lys-Phe bond (positions 6-7 in the peptide) to release the dipeptide Phe-Leu. This behaviour and the effects of inhibitors showed the involvement of metallo-exopeptidases in the N-terminal digestion and a phosphoramidon-sensitive metallo-endopeptidase in the cleavage of the Lys-Phe bond. The degradation patterns in human blood were modelled in terms of the competing pathways involved approximating to first-order kinetics, and an analytical solution obtained via the method of Laplace Transforms. The half-life of THF degradation in whole rat blood sample was found to be significantly lower than in human or mouse.

[A special on epidemic prevention and control: analysis on expression of 2019-nCoV related ACE2 and TMPRSS2 in eye tissues].

This article was published ahead of print on the official website of Chinese Journal of Ophthalmolog on Apirl 22,2020. Objective: Angiotensin converting enzyme 2 (ACE2) and Transmembrane serine protease 2 (TMPRSS2) are the key proteins for 2019-nCoV entry into host cells. To evaluate the potential infection risk of 2019-nCoV on ocular surface, we compared ACE2 and TMPRSS2 expression among different eye tissues. Methods: Experimental study. Thirty mice were assigned to male, female, aged, diabetic and non-diabetic groups, with 6 mice in each group. Real-time PCR was performed to quantify ACE2 and TMPRSS2 gene expression in conjunctiva, cornea, lacrimal gland, iris, lens, retina, lung, heart, kidney, and liver from male mice. Immunohistochemistry staining was applied to visualize the distribution of the two proteins in different mice tissues, and in human corneal and conjunctival sections. Published transcriptome datasets were extracted to generate the expression comparasion of ACE2 and TMPRSS2 between human conjunctival and corneal tissues, and results were analyzed using Mann-Whitney U test. Female mice, aged mice, STZ-induced diabetic mice, diabetic group control mice were also subjected to ACE2 expression analysis. Results were analyzed using Student's t-test. Results: The expression of ACE2 and TMPRSS2 genes were the highest in conjunctiva among all the six mice eye tissues explored. The expression of these two genes in conjunctiva were lower than that in kidney and lung. ACE2 and TMPRSS2 shared similar expression pattern with the staining concentrated in corneal epithelium, conjunctival epithelium and lacrimal gland serous cells. The expression levels of ACE2 showed gender difference. Female mice had lower ACE2 in conjunctiva and cornea than male mice, with the expression levels being only 43% (t=3.269, P=0.031) and 63% (t=4.080, P=0.015) of that in the male conjunctiva and cornea, respectively. Diabetic mice expressed more ACE2 in conjunctiva (1.21-fold, P>0.05) and lacrimal gland (1.10-fold, P>0.05) compared with the control group. No significant difference on ACE2 expression was found between the aged and young adult mice. The expression level of human conjunctiva ACE2 and TMPRSS2 were significantly higher than that in the cornea (P=0.007), with 5.74-fold and 12.84-fold higher in the conjunctiva than in the corneal epithelium cells, which resembled the situation in mice. Conclusion: The observation of high-level ACE2 and TMPRSS2 expression in conjunctiva among the 6 eye tissues examined suggests that conjunctiva serves as an infection target tissue of 2019-nCoV. (Chin J Ophthalmol, 2020, 56:438-446).

The renin-angiotensin-aldosterone system and its inhibitors in the context of the COVID-19 pandemic.

Una de las confusiones que ha generado la pandemia de COVID-19 es la idea de que los inhibidores de la enzima convertidora de la angiotensina y los antagonistas del receptor de la angiotensina II de tipo 1 pueden agravar el daño pulmonar inducido por el SARS-CoV-2 en pacientes de edad avanzada. En este breve comunicado se analiza, desde una perspectiva crítica, la evidencia científica que secunda esta asociación.One of the confusions aroused by the outbreak of COVID-19 pandemic is the idea that angiotensin converting enzyme inhibitors and type 1 angiotensin II receptor may aggravate the lung damage induced by SARS CoV-2 virus in older adult patients. In this brief statement, the scientific evidence supporting this association is analyzed from a critical perspective.

Noncanonical Mechanisms for Direct Bone Marrow Generating Ang II (Angiotensin II) Predominate in CD68 Positive Myeloid Lineage Cells.

Bone marrow (BM) Ang II (angiotensin II) is a major participant in the regulation of hematopoiesis and immunity. The novel tissue substrate Ang-(1-12) [angiotensin-(1-12)] and its cleaving enzyme chymase are an essential source of Ang II production in cardiac tissue. We hypothesized this noncanonical chymase-mediated Ang II-producing mechanism exists in the BM tissue. Immunohistostaining and flow cytometry confirmed the presence of Ang-(1-12) immunoreaction in the BM of SD (Sprague Dawley) rats. Chymase-mediated Ang II-producing activity in BM was ≈1000-fold higher than ACE (angiotensin-converting enzyme)-mediated Ang II-producing activity (4531±137 and 4.2±0.3 fmol/min per mg, respectively; n=6; P<0.001) and 280-fold higher than chymase activity in the left ventricle of 16.3±1.7 fmol/min per mg (P<0.001). Adding a selective chymase inhibitor, TEI-F00806, eliminated almost all 125I-Ang II production. Flow cytometry demonstrated that delta median fluorescence intensity of chymase in cluster of differentiation 68 positive cells was significantly higher than that in cluster of differentiation 68 negative cells (1546±157 and 222±48 arbitrary units, respectively; P=0.0021). Cluster of differentiation 68 positive and side scatter low subsets, considered to be myeloid progenitors, express the highest chymase fluorescence intensity in rat BM. Chymase activity and cellular expression was similar in both male and female rats. In conclusion, myeloid lineage cells, especially myeloid progenitors, have an extraordinary Ang II-producing activity by chymase in the BM.

Clinical features and pathogenesis of liver injury caused by SARS, MERS and COVID-19 / 临床肝胆病杂志

Coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 has become a serious threat to global public health security. Besides lung diseases, severe cases are also accompanied by varying degrees of liver injury. Previous studies have shown that patients infected with severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus may also suffer from liver injury, which is closely associated with disease severity. This article elaborates on the clinical features and pathogenesis of liver injury caused by these three types of highly pathogenic human coronavirus, in order to help clinicians better understand this disease and make accurate decisions.

Functional Cell Receptors for Human Coronavirus / 中华检验医学杂志

Viruses infect host cells by binding to receptors on thesurface of cells. Receptor is an important factor affecting host range and interspecific transmission. In December 2019, an outbreak of unexplained pneumonia occurred in Wuhan, Hubei province. The pathogen was a new coronavirus, named 2019 NovelCoronavirus (2019-nCoV) by WHO. Angiotensin-converting enzyme 2 (ACE2) was found to be the receptor of 2019-nCoV.This review provides a brief overview of human coronavirus receptors and their applications, with a view to providing references for the tracing, cross-species transmission, epidemiological analysis and antiviral and vaccine studies of 2019-nCoV.

Effects of Chronic Exposure to Mercury on Angiotensin-Converting Enzyme Activity and Oxidative Stress in Normotensive and Hypertensive Rats / Efeitos da Exposição Crônica ao Mercúrio sobre a Atividade da Enzima Conversora de Angiotensina e Estresse Oxidativo em Ratos Normotensos e Hipertensos

Abstract Background: Mercury's deleterious effects are associated with increased cardiovascular risk. Objective: To determine whether chronic exposure to inorganic mercury increases the activity of angiotensin-converting enzyme and its relationship with oxidative stress in several organs and tissues. Methods: We studied male Wistar and spontaneously hypertensive rats (SHR) (3-month-old) exposed or not to HgCl2 for 30 days. At the end of treatment, we investigated the following: changes in body weight, hemodynamic parameters, angiotensin-converting enzyme (ACE) activity and oxidative stress in the heart, aorta, lung, brain and kidney in hypertensive compared to normotensive animals. A value of p < 0.05 was considered significant. Results: Chronic exposure to HgCl2 did not affect weight gain in either group. Systolic blood pressure, measured weekly, did not increase in Wistar rats but showed a small increase in SHR rats. We also observed increases in left ventricular end-diastolic pressure and ACE activity in the plasma and hearts of normotensive rats. In the SHR+Hg group, ACE activity increased in plasma but decreased in kidney, lung, heart, brain and aorta. Oxidative stress was assessed indirectly by malondialdehyde (MDA) production, which increased in Hg-treated rats in both plasma and heart. In the SHR+Hg group, MDA increased in heart and aorta and decreased in lungs and brain. Conclusion: These results suggest that chronic exposure to inorganic mercury aggravates hypertension and produces more expressive changes in ACE activity and oxidative stress in SHRs. Such exposure affects the cardiovascular system, representing a risk factor for the development of cardiovascular disorders in normotensive rats and worsening of pre-existing risks for hypertension.

Resumo Fundamento: Os efeitos deletérios do mercúrio estão associados ao risco cardiovascular aumentado. Objetivo: Determinar se a exposição crônica ao mercúrio inorgânico aumenta a atividade da enzima conversora de angiotensina e sua relação com o estresse oxidativo em vários órgãos e tecidos. Métodos: Estudamos ratos Wistar e ratos espontaneamente hipertensos (SHR) (3 meses de idade) expostos ou não a HgCl2 por 30 dias. Ao final do tratamento, investigamos: alterações de peso, parâmetros hemodinâmicos, atividade da enzima conversora de angiotensina (ECA) e estresse oxidativo no coração, aorta, pulmão, cérebro e rim de animais hipertensos comparados a animais normotensos. Um valor de p < 0,05 foi considerado significativo. Resultados: A exposição crônica ao HgCl2 não afetou o ganho de peso em nenhum dos grupos. A pressão arterial sistólica, medida semanalmente, não aumentou em ratos Wistar, mas mostrou um pequeno aumento nos ratos SHR. Também observamos aumentos na pressão diastólica final do ventrículo esquerdo e na atividade da ECA no plasma e no coração de ratos normotensos. No grupo SHR + Hg, a atividade da ECA aumentou no plasma, mas diminuiu no rim, pulmão, coração, cérebro e aorta. O estresse oxidativo foi avaliado indiretamente pela produção de MDA, que aumentou nos ratos tratados com Hg tanto no plasma quanto no coração. No grupo SHR + Hg, o MDA aumentou no coração e na aorta e diminuiu nos pulmões e no cérebro. Conclusão: Estes resultados sugerem que a exposição crônica ao mercúrio inorgânico agrava a hipertensão e produz mudanças mais expressivas na atividade da ECA e no estresse oxidativo em SHRs. Essa exposição afeta o sistema cardiovascular, representando um fator de risco para o desenvolvimento de distúrbios cardiovasculares em ratos normotensos e para piorar riscos pré-existentes para hipertensão.

Relationship between insertion/deletion polymorphism of angiotensin converting enzyme gene and type 2 diabetic kidney disease / 中华检验医学杂志

Objective To explore the interaction of angiotensin converting enzyme (ACE) insertion/deletion(I/D) polymorphism(rs1799752)with diabetic kidney disease (DKD) development as well as its interaction with smoking and obesity in Chinese type 2 diabetic mellitus (T2DM) using the improved experiment method. Methods From June 2016 to March 2018, 300 T2DM patients with DKD [DKD(+)] and 300 T2DM patients without DKD[DKD(-)] were selected from China-Japan Friendship Hospital. The improved Triple Primer Method that combined PCR with capillary electrophoresis was established in this study to detect the ACE genotype. The relevant clinical data as well as the frequencies of genotype and allele of ACE gene I/D polymorphism between two groups were statistically analyzed. Patients were further grouped based on smoking status and obesity for multivariate regression. Results Frequency of the DD genotype and D allele were significantly higher in DKD(+) group than in DKD(-) group [DD genotype:15.0％ (45 cases) vs 7.3％(22 cases),χ2=10.8, P=0.004;D allele:36.5％(219 cases) vs 28.0％(168 cases),χ2=9.92, P=0.02]. Multivariate logistic regression analysis found that D allele of rs1799752 was associated with a significantly higher risk of DKD in both recessive model(OR=1.45, 95％CI:1.06-2.00, P=0.022 after adjustments) and additive model(OR=1.41, 95％CI:1.04-1.90, P=0.025 after adjustments). In the smoker group and the obese group, D allele showed significant relationship with DKD incidence (P<0.05 after adjustments) in both recessive model and dominant model. No such relationships were observed in non-smoker group and non-obese group (P>0.05). Conclusions I/D polymorphism of ACE gene is associated with the incidence of DKD in T2DM patients. DD genotype of the ACE gene is the risk factor for T2DM patients with DKD. D allele may increase DKD incidence in the presence of smoking and obesity.

Add-On Antihypertensive Medications to Angiotensin-Aldosterone System Blockers in Diabetes: A Comparative Effectiveness Study.

BACKGROUND AND OBJECTIVES: In individuals with diabetes, the comparative effectiveness of add-on antihypertensive medications added to an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker on the risk of significant kidney events is unknown. DESIGN, SETTING PARTICIPANTS, & MEASUREMENTS: We used an observational, multicenter cohort of 21,897 individuals with diabetes to compare individuals who added ß-blockers, dihydropyridine calcium channel blockers, loop diuretics, or thiazide diuretics to angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. We examined the hazard of significant kidney events, cardiovascular events, and death using Cox proportional hazard models with propensity score weighting. The composite significant kidney event end point was defined as the first occurrence of a ≥30% decline in eGFR to an eGFR<60 ml/min per 1.73 m2, initiation of dialysis, or kidney transplant. The composite cardiovascular event end point was defined as the first occurrence of hospitalization for acute myocardial infarction, acute coronary syndrome, stroke, or congestive heart failure; coronary artery bypass grafting; or percutaneous coronary intervention, and it was only examined in those free of cardiovascular disease at baseline. RESULTS: Over a maximum of 5 years, there were 4707 significant kidney events, 1498 deaths, and 818 cardiovascular events. Compared with thiazide diuretics, hazard ratios for significant kidney events for ß-blockers, calcium channel blockers, and loop diuretics were 0.81 (95% confidence interval, 0.74 to 0.89), 0.67 (95% confidence interval, 0.58 to 0.78), and 1.19 (95% confidence interval, 1.00 to 1.41), respectively. Compared with thiazide diuretics, hazard ratios of mortality for ß-blockers, calcium channel blockers, and loop diuretics were 1.19 (95% confidence interval, 0.97 to 1.44), 0.73 (95% confidence interval, 0.52 to 1.03), and 1.67 (95% confidence interval, 1.31 to 2.13), respectively. Compared with thiazide diuretics, hazard ratios of cardiovascular events for ß-blockers, calcium channel blockers, and loop diuretics compared with thiazide diuretics were 1.65 (95% confidence interval, 1.39 to 1.96), 1.05 (95% confidence interval, 0.80 to 1.39), and 1.55 (95% confidence interval, 1.05 to 2.27), respectively. CONCLUSIONS: Compared with thiazide diuretics, calcium channel blockers were associated with a lower risk of significant kidney events and a similar risk of cardiovascular events.

Is serum angiotensin converting enzyme level a useful non-invasive marker for liver fibrosis in patients with chronic hepatitis C?

Summary Objective: Chronic hepatitis C (CHC) continues to be a critical problem. The liver fibrosis score is the most valuable tool in determining treatment and prognosis. Liver biopsy is still considered a gold method but, due to unmet needs, new non-invasive markers are required. The aim of this study was to investigate any possible relationship between serum angiotensin-converting enzyme (ACE) levels and the stages of liver fibrosis in patients with CHC. Method: A total 100 CHC and 100 healthy subjects were enrolled in this study. The relationship between serum ACE level and the stages liver fibrosis was investigated using three different formats, as follows: (group [G]-I, classic Ishak's Score from F1 to F6; G-II, mild [F1-2], moderate [F3-4] and severe [F5-6]; G-III, mild [≤ F2] and advanced [F > 2]). The clinical usability of serum ACE level for both groups was also investigated. Results: Median serum ACE levels were higher in the healthy group than in CHC (42.5 [7-119] vs. 36 [7-91] U/I, p=0.002). There was no statistical difference among the three different fibrosis groups (G-I, G-II, G-III, p=0.797, p=0.986, and p=0.874) and no correlation between serum ACE level and the stages of liver fibrosis (r=0.026, p=0.923). The usability of serum ACE for evaluated patients with CHC and healthy subjects were calculated as 47% and 64%, respectively. Conclusion: Our study indicated that there is no relationship or correlation between serum ACE levels and stages of liver fibrosis in patients with CHC. The assessment of serum ACE level using genetically corrected reference values may provide more accurate results.