This study aims to investigate the effects of renin inhibitor aliskiren on kidney injury in human angiotensinogen-renin (AGT-REN) double transgenic hypertensive (dTH) mice and explore its possible mechanism. The dTH mice were divided into hypertension group (HT group) and aliskiren intervention group (HT+Aliskiren group), while wild-type C57BL/6 mice were served as the control group (WT group). Blood pressure data of mice in HT+Aliskiren group were collected after 28 d of subcutaneous penetration of aliskiren (20 mg/kg), and the damage of renal tissue structure and collagen deposition were observed by HE, Masson and PAS staining. The ultrastructure of kidney was observed by transmission electron microscope. Coomassie bright blue staining and biochemical analyzer were used to detect renal function injury. The expression of renin-angiotensin system (RAS) was determined by ELISA and immunohistochemistry. The contents of superoxide dismutase (SOD) and malondialdehyde (MDA) in kidney were determined by chemiluminescence method. The content of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit p47^phox, inducible nitric oxide synthase (iNOS), 3-nitrotyrosine (3-NT), NADPH oxidase 2 (NOX2) and NADPH oxidase 4 (NOX4) were detected by Western blot analysis. The results showed that compared with WT group, the blood pressure of mice in HT group was significantly increased. The renal tissue structure in HT group showed glomerular sclerosis, severe interstitial tubular injury, and increased collagen deposition. In addition, 24 h urinary protein, serum creatinine and urea levels increased. Serum and renal tissue levels of angiotensin II (Ang II) were increased, serum angiotensin-(1-7) [Ang-(1-7)] expression was decreased, and renal Ang-(1-7) expression was elevated. The expressions of ACE, Ang II type 1 receptor (AT₁R) and MasR in renal tissue were increased, while the expression of ACE2 was decreased. MDA content increased, SOD content decreased, and the expressions of p47^phox, iNOS, 3-NT, NOX2 and NOX4 were increased. However, aliskiren reduced blood pressure in dTH mice, improved renal structure and renal function, reduced Ang II and Ang-(1-7) levels in serum and renal tissue, reduced the expression of ACE and AT₁R in renal tissue, increased the expression of ACE2 and MasR in renal tissue, and decreased the above levels of oxidative stress indexes in dTH mice. These results suggest that aliskiren may play a protective role in hypertensive renal injury by regulating the balance between ACE-Ang II-AT₁R and ACE2-Ang-(1-7)-MasR axes and inhibiting oxidative stress.
Animals ; Fumarates/therapeutic use* ; Mice ; Renin/antagonists & inhibitors* ; Amides/therapeutic use* ; Mice, Inbred C57BL ; Hypertension/physiopathology* ; Mice, Transgenic ; Kidney/pathology* ; Angiotensinogen/genetics* ; Renin-Angiotensin System/drug effects* ; NADPH Oxidases/metabolism* ; Male ; Antihypertensive Agents/pharmacology* ; Humans ; Superoxide Dismutase/metabolism* ; NADPH Oxidase 4

OBJECTIVE: To assess the efficacy of Qingda Granule (QDG) in ameliorating hypertension-induced cardiac damage and investigate the underlying mechanisms involved. METHODS: Twenty spontaneously hypertensive rats (SHRs) were used to develope a hypertension-induced cardiac damage model. Another 10 Wistar Kyoto (WKY) rats were used as normotension group. Rats were administrated intragastrically QDG [0.9 g/(kg•d)] or an equivalent volume of pure water for 8 weeks. Blood pressure, histopathological changes, cardiac function, levels of oxidative stress and inflammatory response markers were measured. Furthermore, to gain insights into the potential mechanisms underlying the protective effects of QDG against hypertension-induced cardiac injury, a network pharmacology study was conducted. Predicted results were validated by Western blot, radioimmunoassay immunohistochemistry and quantitative polymerase chain reaction, respectively. RESULTS: The administration of QDG resulted in a significant decrease in blood pressure levels in SHRs (P<0.01). Histological examinations, including hematoxylin-eosin staining and Masson trichrome staining revealed that QDG effectively attenuated hypertension-induced cardiac damage. Furthermore, echocardiography demonstrated that QDG improved hypertension-associated cardiac dysfunction. Enzyme-linked immunosorbent assay and colorimetric method indicated that QDG significantly reduced oxidative stress and inflammatory response levels in both myocardial tissue and serum (P<0.01). CONCLUSIONS Both network pharmacology and experimental investigations confirmed that QDG exerted its beneficial effects in decreasing hypertension-induced cardiac damage by regulating the angiotensin converting enzyme (ACE)/angiotensin II (Ang II)/Ang II receptor type 1 axis and ACE/Ang II/Ang II receptor type 2 axis.
Animals ; Drugs, Chinese Herbal/therapeutic use* ; Hypertension/pathology* ; Renin-Angiotensin System/drug effects* ; Rats, Inbred SHR ; Oxidative Stress/drug effects* ; Male ; Rats, Inbred WKY ; Blood Pressure/drug effects* ; Myocardium/pathology* ; Rats ; Inflammation/pathology*

Retinopathy of prematurity (ROP) is a vision-threatening disorder that leads to pathological growth of the retinal vasculature due to hypoxia. Here, we investigated the potential effects of alamandine, a novel heptapeptide in the renin-angiotensin system (RAS), on hypoxia-induced retinal neovascularization and its underlying mechanisms. In vivo, the C57BL/6J mice with oxygen-induced retinopathy (OIR) were injected intravitreally with alamandine (1.0 μmol/kg per eye). In vitro, human retinal microvascular endothelial cells (HRMECs) were utilized to investigate the effects of alamandine (10 μg/mL) on proliferation, apoptosis, migration, and tubular formation under vascular endothelial growth factor (VEGF) stimulation. Single-cell RNA sequencing (scRNA-seq) matrix data from the Gene Expression Omnibus (GEO) database and RAS-related genes from the Molecular Signatures Database (MSigDB) were sourced for subsequent analyses. By integrating scRNA-seq data across multiple species, we identified that RAS-associated endothelial cell populations were highly related to retinal neovascularization. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis revealed a significant decrease in alamandine levels in both the serum and retina of OIR mice compared to those in the control group. Next, alamandine ameliorated hypoxia-induced retinal pathological neovascularization and physiologic revascularization in OIR mice. In vitro, alamandine effectively mitigated VEGF-induced proliferation, scratch wound healing, and tube formation of HRMECs primarily by inhibiting the hypoxia-inducible factor-1α (HIF-1α)/VEGF pathway. Further, coincubation with D-Pro⁷ (Mas-related G protein-coupled receptor D (MrgD) antagonist) hindered the beneficial impacts of alamandine on hypoxia-induced pathological angiogenesis both in vivo and in vitro. Our findings suggested that alamandine could mitigate retinal neovascularization by targeting the MrgD-mediated HIF-1α/VEGF pathway, providing a potential therapeutic agent for OIR prevention and treatment.
Animals ; Retinal Neovascularization/prevention & control* ; Mice, Inbred C57BL ; Vascular Endothelial Growth Factor A/metabolism* ; Humans ; Mice ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Oligopeptides/therapeutic use* ; Signal Transduction/drug effects* ; Cell Proliferation/drug effects* ; Endothelial Cells/drug effects* ; Retinopathy of Prematurity/drug therapy* ; Apoptosis/drug effects* ; Cell Movement/drug effects* ; Renin-Angiotensin System/drug effects* ; Cells, Cultured

Angiotensin Receptor Antagonists ; therapeutic use ; Betacoronavirus ; Cardiovascular Diseases ; complications ; drug therapy ; Coronavirus Infections ; complications ; Humans ; Pandemics ; Pneumonia, Viral ; complications ; Renin-Angiotensin System ; drug effects

OBJECTIVETo examine the efficacy and safety of dual blockade of the renin-angiotensin-aldosterone system (RAAS) among patients with type 2 diabetic kidney disease.

DATA SOURCESWe searched the major literature repositories, including the Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE, for randomized clinical trials published between January 1990 and October 2015 that compared the efficacy and safety of the use of dual blockade of the RAAS versus the use of monotherapy, without applying any language restrictions. Keywords for the searches included "diabetic nephropathy," "chronic kidney disease," "chronic renal insufficiency," "diabetes mellitus," "dual therapy," "combined therapy," "dual blockade," "renin-angiotensin system," "angiotensin-converting enzyme inhibitor," "angiotensin-receptor blocker," "aldosterone blockade," "selective aldosterone blockade," "renin inhibitor," "direct renin inhibitor," "mineralocorticoid receptor blocker," etc.

STUDY SELECTIONThe selected articles were carefully reviewed. We excluded randomized clinical trials in which the kidney damage of patients was related to diseases other than diabetes mellitus.

RESULTSCombination treatment with an angiotensin-converting enzyme inhibitor supplemented by an angiotensin II receptor blocking agent is expected to provide a more complete blockade of the RAAS and a better control of hypertension. However, existing literature has presented mixed results, in particular, related to patient safety. In view of this, we conducted a comprehensive literature review in order to explain the rationale for dual blockade of the RAAS, and to discuss the pros and cons.

CONCLUSIONSDespite the negative results of some recent large-scale studies, it may be immature to declare that the dual blockade is a failure because of the complex nature of the RAAS surrounding its diversified functions and utility. Further trials are warranted to study the combination therapy as an evidence-based practice.

Angiotensin Receptor Antagonists ; therapeutic use ; Angiotensin-Converting Enzyme Inhibitors ; therapeutic use ; Animals ; Antihypertensive Agents ; therapeutic use ; Diabetes Mellitus, Type 2 ; complications ; Diabetic Nephropathies ; drug therapy ; Humans ; Renin-Angiotensin System ; drug effects

BACKGROUND/AIMS: There has been controversy about the role of Toll-like receptor 2 (TLR2) in renal injury following ureteric obstruction. Although inhibition of the renin angiotensin system (RAS) reduces TLR2 expression in mice, the exact relationship between TLR2 and RAS is not known. The aim of this study was to determine whether the RAS modulates TLR2. METHODS: We used 8-week-old male wild type (WT) and TLR2-knockout (KO) mice on a C57Bl/6 background. Unilateral ureteral obstruction (UUO) was induced by complete ligation of the left ureter. Angiotensin (Ang) II (1,000 ng/kg/min) and the direct renin inhibitor aliskiren (25 mg/kg/day) were administrated to mice using an osmotic minipump. Molecular and histologic evaluations were performed. RESULTS: Ang II infusion increased mRNA expression of TLR2 in WT mouse kidneys (p < 0.05). The expression of renin mRNA in TLR2-KO UUO kidneys was significantly higher than that in WT UUO kidneys (p < 0.05). There were no differences in tissue injury score or mRNA expression of monocyte chemotactic protein 1 (MCP-1), osteopontin (OPN), or transforming growth factor beta (TGF-beta) between TLR2-KO UUO and WT UUO kidneys. However, aliskiren decreased the tissue injury score and mRNA expression of TLR2, MCP-1, OPN, and TGF-beta in WT UUO kidneys (p < 0.05). Aliskiren-treated TLR2-KO UUO kidneys showed less kidney injury than aliskiren-treated WT UUO kidneys. CONCLUSIONS: TLR2 deletion induced activation of the RAS in UUO kidneys. Moreover, inhibition of both RAS and TLR2 had an additive ameliorative effect on UUO injury of the kidney.
Amides/*pharmacology ; Angiotensin II/pharmacology ; Animals ; Disease Models, Animal ; Fibrosis ; Fumarates/*pharmacology ; Kidney/*drug effects/metabolism/pathology ; Male ; Mice, Inbred C57BL ; Mice, Knockout ; Nephritis, Interstitial/genetics/metabolism/pathology/*prevention & control ; RNA, Messenger/genetics/metabolism ; Renin/*antagonists & inhibitors/metabolism ; Renin-Angiotensin System/*drug effects ; Toll-Like Receptor 2/deficiency/drug effects/genetics/*metabolism ; Ureteral Obstruction/*drug therapy/genetics/metabolism/pathology

PURPOSE: In this study, we evaluated the long term beneficial effect of Renin-Angiotensin-Aldosterone System (RAAS) blockade therapy in treatment of Marfan aortopathy. MATERIALS AND METHODS: We reviewed Marfan syndrome (MFS) patients who underwent aortic root replacement (ARR) between January 1996 and January 2011. All patients were prescribed beta-blockers indefinitely. We compared major aortic events including mortality, aortic dissection, and reoperation in patients without RAAS blockade (group 1, n=27) to those with (group 2, n=63). The aortic growth rate was calculated by dividing the diameter change on CT scans taken immediately post-operatively and the latest scan available. RESULTS: There were no differences in clinical parameters except for age which was higher in patients with RAAS blockade. In group 1, 2 (7%) deaths, 5 (19%) aortic dissections, and 7 (26%) reoperations occurred. In group 2, 3 (5%) deaths, 2 (3%) aortic dissections, and 3 (5%) reoperations occurred. A Kaplan-Meier plot demonstrated improved survival free from major aortic events in group 2. On multivariate Cox, RAAS blockade was an independent negative predictor of major aortic events (hazard ratio 0.38, 95% confidence interval 0.30-0.43, p=0.002). Mean diameter change in descending thoracic and supra-renal abdominal aorta was significantly higher in patients without RAAS blockade (p<0.05). CONCLUSION: In MFS patients who underwent ARR, the addition of RAAS blockade to beta-blocker was associated with reduction of aortic dilatation and clinical events.
Adrenergic beta-Antagonists/pharmacology ; Aged ; Aneurysm, Dissecting/complications/mortality/surgery ; *Angiotensin Receptor Antagonists ; Angiotensin-Converting Enzyme Inhibitors/*therapeutic use ; Aorta/pathology/*surgery ; Aortic Aneurysm/complications/mortality/surgery ; Aortic Valve ; Female ; Humans ; Male ; Marfan Syndrome/mortality/*surgery ; Middle Aged ; Renin-Angiotensin System/*drug effects

OBJECTIVESTo investigate the protective effects of Sapindus saponins in spontaneously hypertensive rats, and the possible cellular and molecular mechanisms.

METHODSThirty-two 16-week-old spontaneously hypertensive rats were randomly divided into four groups (8 in each group): model group (placebo), positive control group (27 mg/kg of Captopril Tablets), Sapindus saponins groups (27 mg/kg and 108 mg/kg, respectively). Another 8 healthy Wistar-Kyoto strain (WKY) rats were used as the normal group. The animals were treated for 8 weeks. Blood pressure of rats was determined by non-invasive blood pressure meter (BP-6). Furthermore, the contents of angiotensin II (Ang II) in plasma and myocardial tissue were determined by enzyme-linked immunosorbent assay (ELISA), the gene expression of receptor angiotensin type 1 (AT1R) in aorta was determined by quantitative realtime polymerase chain reaction (qRT-PCR). The protein expression of transforming growth factor-β1 (TGF-β1) and AT1R in heart was determined by immunohistochemical staining. The protein expression of p-phosphorylation of p38 mitogen-activated protein kinase (p-p38MAPK) was determined by Western blotting. The contents of interleukin (IL)-1, IL-6 and tumor necrosis factor (TNF) in serum were determined by radioimmunoassay. And the histopathological and morphological changes of aorta and heart tissue samples were assessed semi-quantitatively by hematoxylin-eosin (HE) or Masson staining.

RESULTSThirty minutes after single or continuous treatment, systolic blood pressure (SBP) was reduced significantly in Sapindus saponins groups. And the contents of AngII, IL-1, IL-6 and TNF-α in serum, the expression of AT1R mRNA, p-p38MAPK and TGF-β1 were significantly suppressed dose-dependently (P<0.05 or P<0.01). With the Sapindus saponins treatment, compared with those of the model group, the cardiac and aortic pathological changes were ameliorated significantly.

CONCLUSIONSOur findings suggest that Sapindus saponins might have protective effects in spontaneously hypertensive rats, the cellular and molecular mechanisms of which might be relevant to the regulation of inflammatory responses mediated by p-p38MAPK signal pathway based on activated Ang II and AT1R.

Angiotensin II ; metabolism ; Animals ; Aorta ; drug effects ; pathology ; physiopathology ; Blood Pressure ; drug effects ; Collagen ; metabolism ; Female ; Hypertension ; blood ; drug therapy ; enzymology ; physiopathology ; Interleukin-1 ; blood ; Interleukin-6 ; blood ; Male ; Phosphorylation ; drug effects ; Protective Agents ; pharmacology ; therapeutic use ; Rats, Inbred SHR ; Receptor, Angiotensin, Type 1 ; metabolism ; Renin-Angiotensin System ; drug effects ; Sapindus ; chemistry ; Saponins ; pharmacology ; therapeutic use ; Transforming Growth Factor beta1 ; metabolism ; Tumor Necrosis Factor-alpha ; blood ; p38 Mitogen-Activated Protein Kinases ; metabolism

OBJECTIVETo observe the reconstruction features of adventitia in senescent rats, and to explore the intervention mechanism of Chinese herbs (CH, extracts from Radix Ginseng, Radix Notoginseng, and Rhizoma Chuanxiong).

METHODSTotally 85 20-month senescent rats were randomly divided into 5 groups according to body weight, i.e., the aging model group, the high dose CH group, the middle dose CH group, the low dose CH group, the Losartan group, 17 in each group. Another 14 2-month old Wistar rats were selected as a young group. Extracts of CH at the daily dose of 1493. 4, 746. 7, and 373. 4 mg/kg were administered to rats in the 3 CH groups respectively by gastrogavage. Losartan suspension at the daily dose of 10 mg/kg was administered to rats in the Losartan group by gastrogavage. Equal volume of distilled water was administered to rats in the aging model group and the young group. All medication was performed once daily. After 15-week intervention, morphological changes of thoracic aorta were observed by HE staining. The types, distribution, and contents of vessel wall collagens were determined using picric acid picrosirius red staining. The plasma renin activity (PRA) , the concentration of rennin angiotensin II (Ang II), and the content of Ang II in adventitia were detected by radioimmunoassay. The content of hydroxyproline ( Hyp) was detected by biochemical analysis. mRNA contents and protein expressions of angiotensin II receptor 1 (AT1R) and angiotensin II receptor 2 (AT2R) were detected by real-time PCR (RT-PCR) and Western blot.

RESULTSCompared with the young group, thickened adventitia, increased adventitia thickness/caliber, accumulated collagen fiber, increased area of type I collagen, decreased area of type III collagen, decreased type III/I collagen area ratio (P <0. 05), decreased plasma PRA and Ang II (P < 0.01, P < 0.05), increased contents of Ang II and Hyp in adventitia, down-regulated mRNA and protein expressions of AT1R, and up-regulated mRNA and protein expression of AT2R could be seen in the aging model group (P < 0.05). Compared with the aging model group, morphological changes could be improved in the 3 CH groups. Adventitia thickness/caliber was reduced in middle and high dose CH groups, as well as the Losartan group. The area of type I collagen was reduced and the area of type III collagen was enlarged, type III/I collagen area ratio obviously increased, contents of adventitia Hyp was obviously lowered in the high dose CH groups and the Losartan group (P < 0.05, P < 0.01). Ang II levels in adventitia decreased in middle and high dose CH groups and the Losartan group (P < 0.05, P < 0.01). There was no statistical difference in PAR among all groups (P > 0.05). Compared with the aging model group, mRNA expression of AT1R all increased in each treatment group (P < 0.01); mRNA expression of AT2R also increased in middle and high dose CH groups (P < 0.05). Protein expression of AT1R increased in the high dose CH group and the Losartan group (P < 0.01, P < 0.05); protein expression of AT2R also increased in middle and high dose CH groups (P < 0.05).

CONCLUSIONSAdventitia remodeling occurred in aged rats, manifested as thickened adventitia and accumulated collagens, disordered ratios of collagen I and III. Its mechanism might be possibly associated with aactivation of renin-angiotensin system (RAS). Extracts from Radix Ginseng, Radix Notoginseng, and Rhizoma Chuanxiong could improve adventitial remodeling possibly by interfering multi-targets, such as Ang II and AT1R, thereby delaying vascular aging.

Adventitia ; drug effects ; Aging ; Angiotensin II ; Animals ; Aorta, Thoracic ; Drugs, Chinese Herbal ; pharmacology ; Losartan ; Panax ; Plant Roots ; RNA, Messenger ; Rats ; Rats, Wistar ; Renin-Angiotensin System ; Rhizome

In order to investigate whether Yinchenhao decoction (YCHD) attenuates hepatic fibrogenesis in the bile duct ligation (BDL) model via recovering and restoring the self-regulation and balance of the renin-angiotensin system (RAS), 33 specific-pathogen-free (SPF) male Sprague-Dawley rats with common BDL and scission were randomly divided into five groups as follows: G1, the sham group (n=4); G2, BDL 7-day group (n=5); G3, BDL+YCHD 430 mg/mL (n=8); G4, BDL+losartan 0.65 mg/mL (ARB group, n=8); G5, model group (BDL without any treatment, n=8). YCHD and losartan (10 mL·kg(-1)·day(-1)) were given by gastric gavage for 16 days following BDL in G3 and G4 groups, respectively. The effect of YCHD on liver fibrosis and the detailed molecular mechanisms were assessed by liver function including total bilirubin (TBIL), direct bilirubin (DBIL), indirect bilirubin (IDBIL), alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Histological changes were observed by transmission electron microscopy (TEM) and Masson trichrome staining. Western blotting was used to detect the protein expression level of the renin-angiotensin system (RAS) components including angiotensin converting enzyme (ACE), angiotensin II type 1 receptor (AT1R), ACE2, angiotensin II (AngII) as well as transforming growth factor β1 (TGFβ1). The experimental data were analyzed by principle component analytical method of pattern recognition. The results showed that biochemically, serum TBIL, DBIL, IDBIL, ALT and AST levels were markedly increased following BDL as compared with the sham group (P<0.05). Serum TBIL, IDBIL and DBIL levels in G3 group were dramatically decreased as compared with G5 and G4 groups (P<0.05). Serum AST level in G3 was significantly lowered than in G5 group (P<0.05), but there was no significant difference in ALT among G3, G4 and G5 groups (P>0.05). Histologically, livers in G3 group showed less hepatocytes necrosis, less bile duct hyperplasia and less collagen formation than in G4 and G5 groups. The protein expression levels of ACE2, ACE, AngII, AT1R and TGFβ1 in G2, G3 and G4 groups were significantly higher than in sham group (P<0.05), and lower than in G5 group (P<0.05). However, the differences among G2, G3 and G4 groups were not significant (P>0.05). ACE2 protein expression in G3 group was significantly higher than in G2 group (P<0.05) and there was no significant difference in comparison with G4 group (P>0.05). Moreover, the protein expression of TGFβ1 in G3 group was significantly lower than in G5 and G4 groups (P<0.05). Our findings suggest that the antifibrotic effects of YCHD may be associated with the decreased classical RAS pathway components and TGFβ1 downexpression so as to recover and rebuild self-regulation of the RAS by elevating the protein expression of ACE2.
Animals ; Disease Models, Animal ; Drugs, Chinese Herbal ; administration & dosage ; chemistry ; pharmacology ; Gene Expression Regulation ; drug effects ; Liver ; drug effects ; pathology ; Liver Cirrhosis ; metabolism ; pathology ; prevention & control ; Liver Function Tests ; Losartan ; administration & dosage ; Male ; Rats ; Rats, Sprague-Dawley ; Renin-Angiotensin System ; drug effects