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Circulation Research Aug 2020Kidney homeostasis is critically determined by the coordinated activity of the renin-angiotensin system (RAS), including the balanced synthesis of its main effector...
RATIONALE
Kidney homeostasis is critically determined by the coordinated activity of the renin-angiotensin system (RAS), including the balanced synthesis of its main effector peptides Ang (angiotensin) II and Ang (1-7). The condition of enzymatic overproduction of Ang II relative to Ang (1-7) is termed RAS dysregulation and leads to cellular signals, which promote hypertension and organ damage, and ultimately progressive kidney failure. ACE2 (angiotensin-converting enzyme 2) and NEP (neprilysin) induce the alternative, and potentially reno-protective axis by enhancing Ang (1-7) production. However, their individual contribution to baseline RAS balance and whether their activities change in chronic kidney disease (CKD) has not yet been elucidated.
OBJECTIVE
To examine whether NEP-mediated Ang (1-7) generation exceeds Ang II formation in the healthy kidney compared with diseased kidney.
METHODS AND RESULTS
In this exploratory study, we used liquid chromatography-tandem mass spectrometry to measure Ang II and Ang (1-7) synthesis rates of ACE, chymase and NEP, ACE2, PEP (prolyl-endopeptidase), PCP (prolyl-carboxypeptidase) in kidney biopsy homogenates in 11 healthy living kidney donors, and 12 patients with CKD. The spatial expression of RAS enzymes was determined by immunohistochemistry. Healthy kidneys showed higher NEP-mediated Ang (1-7) synthesis than Ang II formation, thus displaying a strong preference towards the reno-protective alternative RAS axis. In contrast, in CKD kidneys higher levels of Ang II were recorded, which originated from mast cell chymase activity.
CONCLUSIONS
Ang (1-7) is the dominant RAS peptide in healthy human kidneys with NEP rather than ACE2 being essential for its generation. Severe RAS dysregulation is present in CKD dictated by high chymase-mediated Ang II formation. Kidney RAS enzyme analysis might lead to novel therapeutic approaches for CKD.
Topics: Aged; Angiotensin I; Angiotensin II; Angiotensin-Converting Enzyme 2; Animals; Case-Control Studies; Chymases; Enzyme Inhibitors; Female; Humans; Kidney; Male; Mice, Inbred C57BL; Middle Aged; Neprilysin; Peptide Fragments; Renal Insufficiency, Chronic; Renin-Angiotensin System
PubMed: 32418507
DOI: 10.1161/CIRCRESAHA.119.316151 -
Journal of Managed Care & Specialty... Sep 2018This article provides an overview of the efficacy and safety of once-weekly glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in the treatment of type 2 diabetes... (Review)
Review
UNLABELLED
This article provides an overview of the efficacy and safety of once-weekly glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in the treatment of type 2 diabetes mellitus (T2DM). GLP-1 RAs stimulate pancreatic GLP-1 receptors, which increases insulin secretion, delays gastric emptying, and increases satiety. As a class, GLP-1 RAs lower A1c levels and have been associated with reductions in weight and blood pressure and reduced fluctuations in glucose levels, and they have a low risk of hypoglycemia. Exenatide extended release (ER) and dulaglutide monotherapy have shown similar or superior reductions in A1c and weight compared with various oral antidiabetic drugs (OADs). Semaglutide has been shown to reduce both A1c and body weight compared with placebo and, in head-to-head studies versus both exenatide ER and dulaglutide, showed greater reductions in A1c and body weight. Once-weekly GLP-1 RAs have also been evaluated as add-on therapy in the continuum of care for the treatment of T2DM in combination with a variety of background medications, including 1 or more OADs (metformin, sulfonylureas, and/or thiazolidinediones), basal insulin, and prandial insulin. Gastrointestinal adverse events (e.g., nausea, vomiting, and diarrhea) are the most common side effects with once-weekly GLP-1 RAs. Rates of hypoglycemia, and especially major/severe hypoglycemia, are low with once-weekly GLP-1 RAs but, as expected, are higher when used in combination with sulfonylureas or insulin. These once-weekly GLP-1 RAs provide a safe and effective treatment option for patients with T2DM and may offer improved convenience and possibly greater adherence compared with daily GLP-1 RAs.
DISCLOSURES
This supplement was funded by Novo Nordisk. Handelsman reports research grants from Amgen, AstraZeneca, Bristol-Myers Squibb, Boehringer Ingelheim, Grifols, Janssen, Lexicon, Merck, Novo Nordisk, Regeneron, and Sanofi; speaker fees from Amarin, Amgen, AstraZeneca, Boehringer Ingelheim-Lilly, Janssen, Merck, Novo Nordisk, Regeneron, and Sanofi; and has served in advisory capacity to Amarin, Amgen, AstraZeneca, Boehringer Ingelheim, Eisai, Intarcia, Janssen, Lilly, Merck, Merck-Pfizer, Novo Nordisk, Regeneron, and Sanofi. Cannon reports speaker fees and owns stock in Novo Nordisk. Shannon reports consultant and speaker fees from Novo Nordisk and Boehringer Ingelheim-Lilly Alliance. Schneider reports advisory board fees from Intarcia, Lilly, and Novo Nordisk. Wyne has nothing to disclose.
Topics: Blood Glucose; Body Weight; Diabetes Mellitus, Type 2; Drug Administration Schedule; Exenatide; Glucagon-Like Peptide-1 Receptor; Glucagon-Like Peptides; Glycemic Index; Humans; Hypoglycemic Agents; Immunoglobulin Fc Fragments; Recombinant Fusion Proteins; Treatment Outcome
PubMed: 30156445
DOI: 10.18553/jmcp.2018.24.9-a.s14 -
The Journal of Biological Chemistry Apr 2009The Rassf1-6 polypeptides each contain a Ras/Rap association domain, which enables binding to several GTP-charged Ras-like GTPases, at least in vitro or when... (Review)
Review
The Rassf1-6 polypeptides each contain a Ras/Rap association domain, which enables binding to several GTP-charged Ras-like GTPases, at least in vitro or when overexpressed. The Ras/Rap association domains are followed by SARAH domains, which mediate Rassf heterodimerization with the Mst1/2 protein kinases. Rassf1A is unequivocally a tumor suppressor, and all Rassf proteins behave like tumor suppressors, exhibiting epigenetic silencing of expression in many human cancers and pro-apoptotic and/or anti-proliferative effects when re-expressed in tumor cell lines. Herein, we review the binding of the Rassf polypeptides to Ras-like GTPases and the Mst1/2 kinases and their role in Rassf function.
Topics: Cell Line, Tumor; Cell Proliferation; Dimerization; Epigenesis, Genetic; GTP Phosphohydrolases; Gene Expression Regulation, Neoplastic; Gene Silencing; Humans; Models, Biological; Multigene Family; Neoplasms; Peptides; Protein Binding; Tumor Suppressor Proteins
PubMed: 19091744
DOI: 10.1074/jbc.R800073200 -
Cardiovascular Therapeutics Aug 2013Comorbid obesity, dyslipidemia, and hypertension place patients with type 2 diabetes (T2DM) at greatly increased risk of cardiovascular (CV) disease-related morbidity... (Review)
Review
Comorbid obesity, dyslipidemia, and hypertension place patients with type 2 diabetes (T2DM) at greatly increased risk of cardiovascular (CV) disease-related morbidity and mortality. An urgent need exists for effective treatment for patients with T2DM that encompasses glycemic control, weight loss, and reduction in CV risk factors. The glucagon-like peptide-1 receptor agonists (GLP-1 RAs) liraglutide and exenatide are incretin-based antidiabetes agents. This review examines CV-associated effects of liraglutide and exenatide in animal models and clinical trials with patients with T2DM. Studies support the effectiveness of GLP-1 RAs in reducing hyperglycemia. Further, GLP-1 RAs represent a significant advance in T2DM treatment because they uniquely affect a broad array of CV risk factors through significant weight and systolic blood pressure reduction, improved lipid levels, and possibly, as shown in in vitro studies and animal models, through direct effects on cardiac myocytes and endothelium.
Topics: Animals; Cardiovascular Diseases; Diabetes Mellitus, Type 2; Exenatide; Glucagon-Like Peptide 1; Glucagon-Like Peptide-1 Receptor; Humans; Hypoglycemic Agents; Incretins; Liraglutide; Peptides; Receptors, Glucagon; Risk Factors; Treatment Outcome; Venoms
PubMed: 23865382
DOI: 10.1111/1755-5922.12000 -
Small GTPases Jan 2022RAS activation is a multiple-step process in which linkage of the extracellular stimuli to the RAS activator SOS1 is the main step in RAS activation. GRB2 adaptor...
RAS activation is a multiple-step process in which linkage of the extracellular stimuli to the RAS activator SOS1 is the main step in RAS activation. GRB2 adaptor protein is the main modulator in SOS1 recruitment to the plasma membrane and its activation. This interaction is well studied but the exact mechanism of GRB2-SOS1 complex formation and SOS1 activation has yet remained obscure. Here, a new allosteric mechanism for the GRB2 regulation is described as a prerequisite for the modulation of SOS1 activation. This regulatory mechanism comprises a series of intramolecular interactions which are potentiated by GRB2 interaction with upstream ligands. GRB2, growth factor receptor-bound protein 2; SOS1, son of sevenless 1; RAS, Rat Sarcoma; GEF, guanine nucleotide exchange factor; GAP, GTPase-activating protein; HER2, human epidermal growth factor receptor; SH3, SRC Homology 3; SH2, SRC Homology 2; PRD, proline-rich domain; PRM, proline-rich motif; PRP, proline-rich peptide; RTK, receptor tyrosine kinases.
Topics: Allosteric Regulation; Amino Acid Sequence; GRB2 Adaptor Protein; Guanine Nucleotide Exchange Factors; Ligands; Proline
PubMed: 35703160
DOI: 10.1080/21541248.2022.2089001 -
Asian Journal of Andrology 2022The renin angiotensin system (RAS) appears to influence male fertility at multiple levels. In this work, we analyzed the relationship between the RAS and DNA integrity....
The renin angiotensin system (RAS) appears to influence male fertility at multiple levels. In this work, we analyzed the relationship between the RAS and DNA integrity. Fifty male volunteers were divided into two groups (25 each): control (DNA fragmentation ≤20%) and pathological (DNA fragmentation >20%) cases. Activities of five peptidases controlling RAS were measured fluorometrically: prolyl endopeptidase (which converts angiotensin [A] I and A II to A 1-7), neutral endopeptidase (NEP/CD10: A I to A 1-7), aminopeptidase N (APN/CD13: A III to A IV), aminopeptidase A (A II to A III) and aminopeptidase B (A III to A IV). Angiotensin-converting enzyme (A I to A II), APN/CD13 and NEP/CD10 were also assessed by semiquantitative cytometry and quantitative flow cytometry assays, as were the receptors of all RAS components: A II receptor type 1 (AT1R), A II receptor type 2 (AT2R), A IV receptor (AT4R or insulin-regulated aminopeptidase [IRAP]), (pro)renin receptor (PRR) and A 1-7 receptor or Mas receptor (MasR) None of the enzymes that regulate levels of RAS components, except for APN/CD13 (decrease in fragmented cells), showed significant differences between both groups. Micrographs of RAS receptors revealed no significant differences in immunolabeling patterns between normozoospermic and fragmented cells. Labeling of AT1R (94.3% normozoospermic vs 84.1% fragmented), AT4R (96.2% vs 95.3%) and MasR (97.4% vs 87.2%) was similar between the groups. AT2R (87.4% normozoospermic vs 63.1% fragmented) and PRR (96.4% vs 48.2%) were higher in non-fragmented spermatozoa. These findings suggest that fragmented DNA spermatozoa have a lower capacity to respond to bioactive RAS peptides.
Topics: Angiotensins; DNA Fragmentation; Humans; Insulin; Male; Renin-Angiotensin System; Spermatozoa
PubMed: 34494558
DOI: 10.4103/aja202150 -
International Journal of Molecular... Jun 2020In addition to the classic, endocrine renin-angiotensin system, local renin-angiotensin system (RAS) has been documented in many tissues and organs, including the... (Review)
Review
In addition to the classic, endocrine renin-angiotensin system, local renin-angiotensin system (RAS) has been documented in many tissues and organs, including the ovaries. The localization and functional activity of the two opposing axes of the system, viz. ACE1/Ang II/AT1 and ACE2/Ang-(1-7)/MAS1, differs between animal species and varied according to the stage of follicle development. It appears that the angiotensin peptides and their receptors participate in reproductive processes such as folliculogenesis, steroidogenesis, oocyte maturation, and ovulation. In addition, changes in the constituent compounds of local RAS may contribute to pathological conditions, such as polycystic ovary syndrome, ovarian hyperstimulation syndrome, and ovarian cancer. This review article examines the expression, localization, metabolism, and activity of individual elements of the ACE2/Ang-(1-7)/MAS1 axis in the ovaries of various animal species. The manuscript also presents the relationship between the secretion of gonadotropins and sex hormones and expression of Ang-(1-7) and MAS1 receptors. It also summarizes current knowledge regarding the positive and negative impact of ACE2/Ang-(1-7)/MAS1 axis on ovarian function.
Topics: Angiotensin I; Angiotensin-Converting Enzyme 2; Animals; Female; Humans; Ovary; Peptide Fragments; Proto-Oncogene Mas; Proto-Oncogene Proteins; Receptors, G-Protein-Coupled
PubMed: 32604999
DOI: 10.3390/ijms21134572 -
International Journal of Molecular... Jun 2022Nanoparticulate systems have been widely investigated as delivery vectors for efficient drug delivery in different diseases. Nanostructured lipid carriers (NLC) are...
Nanoparticulate systems have been widely investigated as delivery vectors for efficient drug delivery in different diseases. Nanostructured lipid carriers (NLC) are composed of both solid and liquid lipids (glyceryl dibehenate and diethylene glycol monoethyl ether) and have demonstrated enhanced biological compatibility and increased drug loading capability. Furthermore, the use of peptides, in particular cell-penetrating peptides, to functionalize nanoparticles and enhance cell membrane permeation was explored in this paper. In this paper, we described the synthesis of a new conjugated of tranylcypromine with MAP. In addition, taking into consideration our previous results, this study developed different NLCs loaded with three central nervous system (CNS) drugs (tacrine (TAC), rasagiline (RAS), and tranylcypromine (TCP)) functionalized with model amphipathic peptide (MAP) and evaluated their activity against cancer cells. Particle size analysis demonstrated NLC presented less than 200 nm and a polydispersity index less than 0.3. Moreover, in vitro results showed that conjugation of MAP with drugs led to a higher decrease in cell viability of a neuroblastoma cell line and Caco-2 cell line, more than MAP alone. Furthermore, NLC encapsulation contributed to higher cellular delivery and enhanced toxic activity at lower concentrations when compared with free or co-administration drug-MAP conjugate.
Topics: Caco-2 Cells; Cell-Penetrating Peptides; Central Nervous System Diseases; Drug Carriers; Humans; Lipids; Nanoparticles; Nanostructures; Particle Size; Tranylcypromine
PubMed: 35806112
DOI: 10.3390/ijms23137109 -
Metabolism: Clinical and Experimental Sep 2019Managing type 2 diabetes is complex and necessitates careful consideration of patient factors such as engagement in self-care, comorbidities and costs. Since type 2... (Review)
Review
Managing type 2 diabetes is complex and necessitates careful consideration of patient factors such as engagement in self-care, comorbidities and costs. Since type 2 diabetes is a progressive disease, many patients will require injectable agents, usually insulin. Recent ADA-EASD guidelines recommend glucagon-like peptide 1 receptor agonists (GLP-1 RAs) as first injectable therapy in most cases. The basis for this recommendation is the similar glycemic efficacy of GLP-1 RAs and insulin, but with GLP-1 RAs promoting weight loss instead of weight gain, at lower hypoglycemia risk, and with cardiovascular benefits in patients with pre-existing cardiovascular disease. GLP-1 RAs also reduce burden of glucose self-monitoring. However, tolerability and costs are important considerations, and notably, rates of drug discontinuation are often higher for GLP-1 RAs than basal insulin. To minimize risk of gastrointestinal symptoms patients should be started on lowest doses of GLP-1 RAs and up-titrated slowly. Overall healthcare costs may be lower with GLP-1 RAs compared to insulin. Though patient-level costs may still be prohibitive, GLP-1 RAs can replace 50-80 units of insulin daily and reduce costs associated with glucose self-monitoring. Decisions regarding initiating injectable therapy should be individualized. This review provides a framework to guide decision-making in the real-world setting.
Topics: Animals; Diabetes Mellitus, Type 2; Glucagon-Like Peptide 1; Glucagon-Like Peptide-1 Receptor; Humans; Hypoglycemic Agents; Injections; Insulin
PubMed: 31255662
DOI: 10.1016/j.metabol.2019.06.012 -
Journal of Clinical Pharmacy and... Sep 2020People with type 2 diabetes (T2D) are at increased risk of cardiovascular disease (CVD), which in turn is associated with increased morbidity and mortality. The impact... (Review)
Review
WHAT IS KNOWN AND OBJECTIVE
People with type 2 diabetes (T2D) are at increased risk of cardiovascular disease (CVD), which in turn is associated with increased morbidity and mortality. The impact of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) on cardiovascular (CV) outcomes has been investigated in CV outcomes trials (CVOTs). This review aims to help pharmacists and other healthcare professionals (HCPs) gain a better understanding of such CVOTs in T2D with a primary focus on the once-weekly (QW) GLP-1 RAs.
METHODS
This narrative review mainly focuses on the evaluation of the similarities and differences in the design and results of CVOTs involving currently approved and marketed QW GLP-1 RAs-semaglutide subcutaneous, exenatide extended-release (ER) and dulaglutide. Results from CVOTs of dipeptidyl peptidase-4 inhibitors (DPP4is) and sodium-glucose cotransporter-2 inhibitors (SGLT2is) are also included.
RESULTS AND DISCUSSION
Three CVOTs of QW GLP-1 RAs were identified for inclusion in this review: SUSTAIN 6 (semaglutide), EXSCEL (exenatide ER) and REWIND (dulaglutide), all of which varied in terms of trial design, patient demographics and other baseline characteristics. Results from these CVOTs demonstrated the CV safety of QW GLP-1 RAs compared with standard of care. Additionally, CV and renal benefits were demonstrated for semaglutide and dulaglutide, but not for exenatide ER. The CV safety of four DPP4is and three SGLT2is was demonstrated. None of the DPP4is had a CV or renal benefit, whereas all three SGLT2is were associated with CV and renal benefits.
WHAT IS NEW AND CONCLUSION
This article provides an overview of the results from QW GLP-1 RA CVOTs, including the recently published results for dulaglutide, and places them within the broader T2D treatment landscape to help HCPs make informed decisions in daily practice. The QW GLP-1 RAs with benefits reaching beyond glycaemic control can provide a comprehensive treatment option for people with T2D at high risk of CVD, with CVD or chronic kidney disease.
Topics: Cardiovascular Diseases; Delayed-Action Preparations; Diabetes Mellitus, Type 2; Drug Administration Schedule; Exenatide; Glucagon-Like Peptide-1 Receptor; Glucagon-Like Peptides; Humans; Hypoglycemic Agents; Immunoglobulin Fc Fragments; Recombinant Fusion Proteins; Research Design
PubMed: 32910492
DOI: 10.1111/jcpt.13226