• Biomolecules & Therapeutics
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• 제14권2호
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• pp.106-109
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• 2006

Neprilysin (Nep) is known to be important to degrade $A{\beta}$ derived from amyloid precursor protein (APP) by cleavage with $\beta-and\;\gamma$-secretases. In order to determine whether a correspondence between $A{\beta}-42/{\gamma}-secretase$ activity and Nep levels exists in postnatal aging of transgenic mice expressing either neuron-specific enolase (NSE)-controlled human mutant presenilin-2 (hPS2m) or APPsw alone, the levels of Nep expression and $A{\beta}-42/{\gamma}-secretase$ activity were examined age of 5, 12, and 20 months, respectively. The levels of Nep expression in both types of transgenic brains were decreased relative to those of control mice in a aging-related manner, while the level of $A{\beta}-42/{\gamma}-secretase$ activity was reversibly increased. Thus, changes in $A{\beta}-42$ may all reflect variation in amounts of Nep enzyme.

• Toxicological Research
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• 제29권4호
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• pp.235-240
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• 2013

Extracellular accumulation of amyloid beta protein ($A{\beta}$) plays a central role in Alzheimer's disease (AD). Some metals, such as copper, lead, and aluminum can affect the $A{\beta}$ accumulation in the brain. However, the effect of mercury on $A{\beta}$ accumulation in the brain is not clear. Thus, this study was proposed to estimate whether mercury concentration affects $A{\beta}$ accumulation in PC12 cells. We treated 10, 100, and 1000 nM $HgCl_2$ (Hg) or $CH_3HgCl_2$ (MeHg) for 48 hr in PC12 cells. After treatment, $A{\beta}_{40}$ in culture medium increased in a dose- and time-dependent manner. Hg and MeHg increased amyloid precursor protein (APP), which is related to $A{\beta}$ production. Neprilysin (NEP) levels in PC12 cells were decreased by Hg and MeHg treatment. These results suggested that Hg induced $A{\beta}$ accumulation through APP overproduction and reduction of NEP.

• Korean Circulation Journal
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• 제52권3호
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• pp.173-197
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• 2022

Treatment options for patients with heart failure (HF) with reduced ejection fraction (HFrEF) have expanded considerably over the past few decades. Whereas neurohormonal modulation remains central to the management of patients with HFrEF, other pathways have been targeted with drugs that have novel mechanisms of action. The angiotensin receptor-neprilysin inhibitors (ARNIs) which enhance levels of compensatory molecules such as the natriuretic peptides while simultaneously providing angiotensin receptor blockade have emerged as the preferred strategy for inhibiting the renin angiotensin system. Sodium glucose cotransporter 2 (SGLT2) inhibitors which were developed as hypoglycemic agents have been shown to improve outcomes in patients with HF regardless of their diabetic status. These agents along with beta blockers and mineralocorticoid receptor antagonists are the core medical therapies for patients with HFrEF. Additional approaches using ivabradine to slow heart rate in patients with sinus rhythm, the hydralazine/isosorbide dinitrate combination to unload the heart, digoxin to provide inotropic support and vericiguat to augment cyclic guanosine monophosphate production have been shown in well-designed trials to have beneficial effects in the HFrEF population and are used as adjuncts to the core therapies in selected patients. This review provides an overview of the medical management of patients with HFrEF with focus on the major developments that have taken place in the field. It offers prospective of how these drugs should be employed in clinical practice and also a glimpse into some strategies that may prove to be useful in the future.

• Biomolecules & Therapeutics
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• 제20권3호
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• pp.245-255
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• 2012

Amyloid-${\beta}$ peptide ($A{\beta}$) is still best known as a molecule to cause Alzheimer's disease (AD) through accumulation and deposition within the frontal cortex and hippocampus in the brain. Thus, strategies on developing AD drugs have been focused on the reduction of $A{\beta}$ in the brain. Since accumulation of $A{\beta}$ depends on the rate of its synthesis and clearance, the metabolic pathway of $A{\beta}$ in the brain and the whole body should be carefully explored for AD research. Although the synthetic pathway of $A{\beta}$ is equally important, we summarize primarily the clearance pathway in this paper because the former has been extensively reviewed in previous studies. The clearance of $A{\beta}$ from the brain is accomplished by several mechanisms which include non-enzymatic and enzymatic pathways. Nonenzymatic pathway includes interstitial fluid drainage, uptake by microglial phagocytosis, and transport across the blood vessel walls into the circulation. Multiple $A{\beta}$-degrading enzymes (ADE) implicated in the clearance process have been identified, which include neprilysin, insulin-degrading enzyme, matrix metalloproteinase-9, glutamate carboxypeptidase II and others. A series of studies on $A{\beta}$ clearance mechanism provide new insight into the pathogenesis of AD at the molecular level and suggest a new target for the development of novel therapeutics.

• Nutrition Research and Practice
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• 제14권6호
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• pp.593-605
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• 2020

BACKGROUND/OBJECTIVES: Alzheimer's disease is common age-related neurodegenerative condition characterized by amyloid beta (Aβ) accumulation that leads cognitive impairment. In the present study, we investigated the protective effect of paeoniflorin (PF) against Aβ-induced neuroinflammation and the underlying mechanism in C6 glial cells. MATERIALS/METHODS: C6 glial cells were treated with PF and Aβ_25-35, and cell viability, nitric oxide (NO) production, and pro-inflammatory cytokine release were measured. Furthermore, the mechanism underlying the effect of PF on inflammatory responses and Aβ degradation was determined by Western blot. RESULTS: Aβ_25-35 significantly reduced cell viability, but this reduction was prevented by the pretreatment with PF. In addition, PF significantly inhibited Aβ_25-35-induced NO production in C6 glial cells. The secretion of interleukin (IL)-6, IL-1β, and tumor necrosis factor-alpha was also significantly reduced by PF. Further mechanistic studies indicated that PF suppressed the production of these pro-inflammatory cytokines by regulating the nuclear factor-kappa B (NF-κB) pathway. The protein levels of inducible NO synthase and cyclooxygenase-2 were downregulated and phosphorylation of NF-κB was blocked by PF. However, PF elevated the protein expression of inhibitor kappa B-alpha and those of Aβ degrading enzymes, insulin degrading enzyme and neprilysin. CONCLUSIONS: These findings indicate that PF exerts protective effects against Aβ-mediated neuroinflammation by inhibiting NF-κB signaling, and these effects were associated with the enhanced activity of Aβ degradation enzymes.

• 동의생리병리학회지
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• 제31권6호
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• pp.313-327
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• 2017

The purpose of this study is to predict the effects of macroscopic and integrative therapies by finding active ingredients, potential targets of Astragalus membranaceus (Am) and Cornus officinalis (Co) for diabetic nephropathy. We have constructed network pharmacology-based systematic and network methodology by system biology, chemical structure, chemogenomics. We found several active ingredients of Astragalus membranaceus (Am) and Cornus officinalis (Co) that were speculated to bind to specific receptors which had been known to have a role in the progression of diabetic nephropathy. Four components of Am and eleven components of Co could bind to iNOS; two ingredients of Am and six ingredients of Co could docking to cGB-PDE; one component of Am and nine components of Co could bind to ACE; three ingredients of Co with neprilysin; three components of Co with ET-1 receptor; four ingredients of Am and fourteen ingredients of Co with mineralocorticoid receptor; one component of Am and seven components of Co with interstitial collagenase; one ingredient of Am and ten ingredients of Co with membrane primary amine oxidase; one component of Am and four components of Co with JAK2; two ingredients of Am and one ingredient of Co with MAPK 12; one component of Am and five components of Co could docking to TGF-beta receptor type-1. From this work we could speculate that the possible mechanisms of Am and Co for diabetic nephropathy are anti-inflammatory, antioxidant and antihypertensive effects.

• International Journal of Heart Failure
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• 제6권3호
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• pp.129-136
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• 2024

Background and Objectives: Heart failure (HF) is a leading cause of hospitalization and death worldwide. The Steady Movement with Innovating Leadership for Heart Failure (SMILE HF) aims to evaluate the clinical characteristics, management, hospital course, and long-term outcomes of patients hospitalized for acute HF in South Korea. Methods: This prospective, observational multicenter cohort study was conducted on consecutive patients hospitalized for acute HF in nine university hospitals since September 2019. Enrolment of 2000 patients should be completed in 2024, and follow-up is planned through 2025. Results: Interim analysis of 1,052 consecutive patients was performed to understand the baseline characteristics. The mean age was 69±15 years; 57.6% were male. The mean left ventricular ejection fraction was 39±15%. The prevalences of HF with reduced ejection fraction, HF with mildly reduced ejection fraction, and HF with preserved ejection fraction were 50.9%, 15.3%, and 29.2%. Ischemic cardiomyopathy (CMP) was the most common etiology (32%), followed by tachycardia-induced CMP (12.8%) and idiopathic dilated CMP (9.5%). The prescription rate of angiotensin-converting enzyme inhibitor/angiotensin receptor blockers/angiotensin receptor/neprilysin inhibitor, beta-blockers, spironolactone, and sodium-glucose cotransporter-2 inhibitors at discharge were 76.8%, 66.5%, 50.0%, and 17.5%, respectively. The post-discharge 90-day mortality and readmission rates due to HF aggravation were 2.0% and 6.4%, respectively. Our analysis reveals the current state of acute HF in South Korea. Conclusions: Our interim analysis provides valuable insights into the clinical characteristics, management, and early outcomes of acute HF patients in South Korea, highlighting the current state and treatment patterns in this population.