scholarly journals Urinary angiotensinogen as a biomarker for acute to chronic kidney injury transition – prognostic and mechanistic implications

2018 ◽  
Vol 132 (21) ◽  
pp. 2383-2385 ◽  
Author(s):  
Katie L. Connor ◽  
Laura Denby
Keyword(s):  
Kidney Injury ◽  
Renin Angiotensin System ◽  
Ischaemia Reperfusion Injury ◽  
Angiotensin System ◽  
Urinary Angiotensinogen ◽  
Tubular Necrosis ◽  
Ischaemia Reperfusion ◽  
Structural Recovery ◽  
Chronic Kidney Injury ◽  
Injury Model

Accurate biomarkers that both predict the progression to, and detect the early stages of chronic kidney disease (CKD) are lacking, resulting in difficulty in identifying individuals who could potentially benefit from targeted intervention. In a recent issue [Clinical Science (2018) 132, 2121–2133], Cui et al. examine the ability of urinary angiotensinogen (uAGT) to predict the progression of acute kidney injury (AKI) to CKD. They principally employ a murine ischaemia reperfusion injury model to study this and provide data from a small prospective study of patients with biopsy proven acute tubular necrosis. The authors suggest that uAGT is a dynamic marker of renal injury that could be used to predict the likelihood of structural recovery following AKI. Here we comment on their findings, exploring the clinical utility of uAGT as a biomarker to predict AKI to CKD transition and perhaps more controversially, to discuss whether the early renin–angiotensin system blockade following AKI represents a therapeutic target.

ACE2–angiotensin-(1–7)–Mas axis in renal ischaemia/reperfusion injury in rats

2010 ◽  
Vol 119 (9) ◽  
pp. 385-394 ◽  
Author(s):  
Kátia D. da Silveira ◽  
Kênia S. Pompermayer Bosco ◽  
Lúcio R. L. Diniz ◽  
Adriana K. Carmona ◽  
Giovanni D. Cassali ◽  
...  
Keyword(s):  
Kidney Injury ◽  
Renin Angiotensin System ◽  
At1 Receptor ◽  
Converting Enzyme ◽  
Angiotensin I ◽  
Ischaemia Reperfusion Injury ◽  
Mas Receptor ◽  
Angiotensin I Converting Enzyme ◽  
Ischaemia Reperfusion ◽  
Renal Expression

AngII (angiotensin II), ACE (angiotensin I-converting enzyme) and the AT1 receptor (AngII type 1 receptor) are associated with the inflammatory process and microvascular dysfunction of AKI (acute kidney injury) induced by renal I/R (ischaemia/reperfusion). However, Ang-(1–7) [angiotensin-(1–7)], ACE2 (angiotensin I-converting enzyme 2) and the Mas receptor also play a role in renal disease models. Therefore, in the present study, we have examined the renal profile of Ang-(1–7), ACE2 and the Mas receptor in renal I/R and compared them with that of AngII, ACE and the AT1 receptor. Male Wistar rats were submitted to left nephrectomy and ischaemia (45 min) followed by reperfusion (2 or 4 h) in the right kidney. At 4 h of reperfusion, renal AngII was increased (P<0.01) and renal Ang-(1–7) was decreased substantially (P<0.05), although plasma levels of both angiotensins were unchanged. In addition, renal I/R decreased the renal mRNA expression of renin (P<0.05), AT1 receptors (P<0.001) and ACE2 (P<0.05). At 2 and 4 h of reperfusion, renal ACE activity was reduced (P<0.05). On the other hand, renal expression of the Mas receptor was greatly increased at 4 h of reperfusion (P<0.01), which was confirmed by immunohistochemical and Western blot analysis. In conclusion, increased renal expression of the Mas receptor associated with changes in the RAS (renin–angiotensin system)-related peptidases support an important role for the ACE2–Ang-(1–7)–Mas axis in AKI.

Urinary angiotensinogen predicts progressive chronic kidney disease after an episode of experimental acute kidney injury

2018 ◽  
Vol 132 (19) ◽  
pp. 2121-2133 ◽  
Author(s):  
Shuang Cui ◽  
Liling Wu ◽  
Xiaodan Feng ◽  
Huanjuan Su ◽  
Zhanmei Zhou ◽  
...  
Keyword(s):  
Renal Fibrosis ◽  
Structural Changes ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Kidney Injury ◽  
Renin Angiotensin System ◽  
Operating Characteristics ◽  
Ckd Progression ◽  
Urinary Angiotensinogen ◽  
Structural Recovery

One of the major obstacles to prevent AKI-CKD transition is the lack of effective methods to follow and predict the ongoing kidney injury after an AKI episode. In the present study, we test the utility of urinary angiotensinogen (UAGT) for dynamically evaluating renal structural changes and predicting AKI-CKD progression by using both mild and severe bilateral renal ischemia/reperfusion injury mice. UAGT returns to pre-ischemic levels 14 days after mild AKI followed by kidney architecture restoration, whereas sustained increase in UAGT accompanies by ongoing renal fibrosis after severe AKI. UAGT at day 14–42 correlates with renal fibrosis 84 days after AKI. For predicting fibrosis at day 84, the area under receiver operating characteristics curve of UAGT at day 14 is 0.81. Persistent elevation in UAGT correlates with sustained activation of intrarenal renin–angiotensin system (RAS) during AKI-CKD transition. Abrogating RAS activation post AKI markedly reduced renal fibrosis, with early RAS intervention (from 14 days after IRI) more beneficial than late intervention (from 42 days after IRI) in alleviating fibrosis. Importantly, UAGT decreases after RAS intervention, and its level at day 14–28 correlates with the extent of renal fibrosis at day 42 post RAS blockade. A pilot study conducted in patients with acute tubular necrosis finds that compared with those recovered, patients with AKI-CKD progression exhibits elevated UAGT during the 3-month follow-up after biopsy. Our study suggests that UAGT enables the dynamical monitoring of renal structural recovery after an AKI episode and may serve as an early predictor for AKI-CKD progression and treatment response.

scholarly journals ACE2 Shedding and the Role in COVID-19

2022 ◽  
Vol 11 ◽  
Author(s):  
Jieqiong Wang ◽  
Huiying Zhao ◽  
Youzhong An
Keyword(s):  
Amino Acids ◽  
Viral Entry ◽  
Kidney Injury ◽  
Renin Angiotensin System ◽  
Underlying Mechanism ◽  
Ang Ii ◽  
Converting Enzyme ◽  
Angiotensin System ◽  
Angiotensin Converting Enzyme 2 ◽  
Transmembrane Glycoprotein

Angiotensin converting enzyme 2 (ACE2), a transmembrane glycoprotein, is an important part of the renin-angiotensin system (RAS). In the COVID-19 epidemic, it was found to be the receptor of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2). ACE2 maintains homeostasis by inhibiting the Ang II-AT1R axis and activating the Ang I (1-7)-MasR axis, protecting against lung, heart and kidney injury. In addition, ACE2 helps transport amino acids across the membrane. ACE2 sheds from the membrane, producing soluble ACE2 (sACE2). Previous studies have pointed out that sACE2 plays a role in the pathology of the disease, but the underlying mechanism is not yet clear. Recent studies have confirmed that sACE2 can also act as the receptor of SARS-COV-2, mediating viral entry into the cell and then spreading to the infective area. Elevated concentrations of sACE2 are more related to disease. Recombinant human ACE2, an exogenous soluble ACE2, can be used to supplement endogenous ACE2. It may represent a potent COVID-19 treatment in the future. However, the specific administration concentration needs to be further investigated.

scholarly journals Urinary Angiotensinogen Accurately Reflects Intrarenal Renin-Angiotensin System Activity

2010 ◽  
Vol 31 (4) ◽  
pp. 318-325 ◽  
Author(s):  
Maki Urushihara ◽  
Shuji Kondo ◽  
Shoji Kagami ◽  
Hiroyuki Kobori
Keyword(s):  
Renin Angiotensin System ◽  
Angiotensin System ◽  
System Activity ◽  
Renin Angiotensin ◽  
Urinary Angiotensinogen

Abstract 188: Loss of Renal Prolyl Carboxypeptidase in Mice With Chronic Kidney Disease

Hypertension ◽  
2013 ◽  
Vol 62 (suppl_1) ◽  
Author(s):  
Orly Leiva ◽  
Khalid M Elased ◽  
Mariana Morris ◽  
Nadja Grobe
Keyword(s):  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
Protein Expression ◽  
Western Blot ◽  
Kidney Injury ◽  
Renin Angiotensin System ◽  
Left Renal Artery ◽  
Renal Tubules ◽  
Ang Ii ◽  
Chronic Kidney Injury

There are 26 million adults with chronic kidney disease (CKD) in the U.S. and the incidence continues to increase. It is well documented that the activation of the renin angiotensin system and the elevated formation of angiotensin (Ang) II both contribute to renal pathophysiology in CKD. Emerging evidence suggests that the Ang II degrading protease prolyl carboxypeptidase (PCP) is renoprotective. Thus, we investigated protein expression and activity of renal PCP using immunofluorescence, western blot and mass spectrometry in a mouse model of CKD. Renal injury in male C57Bl6 mice was caused by constriction of the left renal artery using silver clips (2K1C-method). Blood pressure measurements by radiotelemetry revealed a significant increase of 36.1 ± 3.9 mm Hg in 2K1C animals compared with control animals 1 week after clip placement (p<0.0001). Using immunofluorescence and confocal microscopy, PCP was localized in the Bowman’s capsule of the glomerulus and in proximal and distal renal tubules. Western blot analysis showed PCP was significantly reduced in clipped 2K1C kidneys compared to unclipped kidneys of the 2K1C mice or compared to control mice (clipped 0.04 ± 0.02 vs unclipped 0.58 ± 0.16 vs control 0.65 ± 0.18, p < 0.05). In addition, renal PCP enzyme activity was found to be markedly reduced in 2K1C kidneys as assessed by mass spectrometric based enzyme assays (clipped 37.1 ± 4.3 pmol Ang-(1-7)/h/μg vs unclipped 77.3 ± 12.3 pmol Ang-(1-7)/h/μg vs control 120.7 ± 14.7 pmol Ang-(1-7)/h/μg, p < 0.01). In contrast, protein expression of prolyl endopeptidase, another enzyme capable of converting Ang II into Ang-(1-7), was not affected. Notably, renal pathologies were exacerbated in the 2K1C model as revealed by a significant increase in mesangial expansion (clipped 34.6 ± 3.1 vs unclipped 52.1 ± 4.0 vs control 1.2 ± 2.1, p < 0.0001) and renal fibrosis (clipped 57.5 ± 0.9 vs unclipped 33.0 ± 0.7 vs control 3.3 ± 0.2, p < 0.0001). Results suggest that PCP is suppressed in chronic kidney injury and that this downregulation may attenuate renoprotective effects via impaired Ang II degradation by PCP. Therefore, Ang II processing by PCP may have clinical implications in patients with renal pathologies.

Sign in / Sign up

Export Citation Format

Share Document