Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
80
result(s) for
"Chen, Che-Hong"
Sort by:
Correcting glucose-6-phosphate dehydrogenase deficiency with a small-molecule activator
2018
Glucose-6-phosphate dehydrogenase (G6PD) deficiency, one of the most common human genetic enzymopathies, is caused by over 160 different point mutations and contributes to the severity of many acute and chronic diseases associated with oxidative stress, including hemolytic anemia and bilirubin-induced neurological damage particularly in newborns. As no medications are available to treat G6PD deficiency, here we seek to identify a small molecule that corrects it. Crystallographic study and mutagenesis analysis identify the structural and functional defect of one common mutant (Canton, R459L). Using high-throughput screening, we subsequently identify AG1, a small molecule that increases the activity of the wild-type, the Canton mutant and several other common G6PD mutants. AG1 reduces oxidative stress in cells and zebrafish. Furthermore, AG1 decreases chloroquine- or diamide-induced oxidative stress in human erythrocytes. Our study suggests that a pharmacological agent, of which AG1 may be a lead, will likely alleviate the challenges associated with G6PD deficiency.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency provides insufficient protection from oxidative stress, contributing to diverse human pathologies. Here, the authors identify a small molecule that increases the activity and/or stability of mutant G6PD and show that it reduces oxidative stress in zebrafish and hemolysis in isolated human erythrocytes.
Journal Article
ALDH2 variance in disease and populations
by
Kraemer, Benjamin R.
,
Chen, Che-Hong
,
Mochly-Rosen, Daria
in
Alcohol Drinking - genetics
,
Alcohol use
,
Aldehyde Dehydrogenase, Mitochondrial - genetics
2022
The ALDH2*2 missense variant that commonly causes alcohol flushing reactions is the single genetic polymorphism associated with the largest number of traits in humans. The dysfunctional ALDH2 variant affects nearly 8% of the world population and is highly concentrated among East Asians. Carriers of the ALDH2*2 variant commonly present alterations in a number of blood biomarkers, clinical measurements, biometrics, drug prescriptions, dietary habits and lifestyle behaviors, and they are also more susceptible to aldehyde-associated diseases, such as cancer and cardiovascular disease. However, the interaction between alcohol and ALDH2-related pathology is not clearly delineated. Furthermore, genetic evidence indicates that the ALDH2*2 variant has been favorably selected for in the past 2000-3000 years. It is therefore necessary to consider the disease risk and mechanism associated with ALDH2 deficiency, and to understand the possible beneficial or protective effect conferred by ALDH2 deficiency and whether the pleiotropic effects of ALDH2 variance are all mediated by alcohol use.
Journal Article
ALDH2 polymorphism and alcohol-related cancers in Asians: a public health perspective
by
Chen, Che-Hong
,
Hsiao, Jenn-Ren
,
Chang, Jeffrey S.
in
Alcohol-Related Disorders - enzymology
,
Alcohol-Related Disorders - epidemiology
,
Alcohol-Related Disorders - genetics
2017
The occurrence of more than 200 diseases, including cancer, can be attributed to alcohol drinking. The global cancer deaths attributed to alcohol-consumption rose from 243,000 in 1990 to 337,400 in 2010. In 2010, cancer deaths due to alcohol consumption accounted for 4.2% of all cancer deaths. Strong epidemiological evidence has established the causal role of alcohol in the development of various cancers, including esophageal cancer, head and neck cancer, liver cancer, breast cancer, and colorectal cancer. The evidence for the association between alcohol and other cancers is inconclusive. Because of the high prevalence of
ALDH2*2
allele among East Asian populations, East Asians may be more susceptible to the carcinogenic effect of alcohol, with most evidence coming from studies of esophageal cancer and head and neck cancer, while data for other cancers are more limited. The high prevalence of
ALDH2*2
allele in East Asian populations may have important public health implications and may be utilized to reduce the occurrence of alcohol-related cancers among East Asians, including: 1) Identification of individuals at high risk of developing alcohol-related cancers by screening for
ALDH2
polymorphism; 2) Incorporation of
ALDH2
polymorphism screening into behavioral intervention program for promoting alcohol abstinence or reducing alcohol consumption; 3) Using
ALDH2
polymorphism as a prognostic indicator for alcohol-related cancers; 4) Targeting ALDH2 for chemoprevention; and 5) Setting guidelines for alcohol consumption among ALDH2 deficient individuals. Future studies should evaluate whether these strategies are effective for preventing the occurrence of alcohol-related cancers.
Journal Article
Activation of Aldehyde Dehydrogenase-2 Reduces Ischemic Damage to the Heart
by
Hurley, Thomas D
,
Churchill, Eric N
,
Mochly-Rosen, Daria
in
Agonists
,
aldehyde dehydrogenase
,
Aldehyde Dehydrogenase - antagonists & inhibitors
2008
There is substantial interest in the development of drugs that limit the extent of ischemia-induced cardiac damage caused by myocardial infarction or by certain surgical procedures. Here, using an unbiased proteomic search, we identified mitochondrial aldehyde dehydrogenase 2 (ALDH2) as an enzyme whose activation correlates with reduced ischemic heart damage in rodent models. A high-throughput screen yielded a small-molecule activator of ALDH2 (Alda-1) that, when administered to rats before an ischemic event, reduced infarct size by 60%, most likely through its inhibitory effect on the formation of cytotoxic aldehydes. In vitro, Alda-1 was a particularly effective activator of ALDH2*2, an inactive mutant form of the enzyme that is found in 40% of East Asian populations. Thus, pharmacologic enhancement of ALDH2 activity may be useful for patients with wild-type or mutant ALDH2 who are subjected to cardiac ischemia, such as during coronary bypass surgery.
Journal Article
Impact of common ALDH2 inactivating mutation and alcohol consumption on Alzheimer’s disease
2023
Aldehyde dehydrogenase 2 (ALDH2) is an enzyme found in the mitochondrial matrix that plays a central role in alcohol and aldehyde metabolism. A common ALDH2 polymorphism in East Asians descent (called ALDH2*2 or E504K missense variant, SNP ID: rs671), present in approximately 8% of the world’s population, has been associated with a variety of diseases. Recent meta-analyses support the relationship between this ALDH2 polymorphism and Alzheimer’s disease (AD). And AD-like pathology observed in ALDH2 –/– null mice and ALDH2*2 overexpressing transgenic mice indicate that ALDH2 deficiency plays an important role in the pathogenesis of AD. Recently, the worldwide increase in alcohol consumption has drawn attention to the relationship between heavy alcohol consumption and AD. Of potential clinical significance, chronic administration of alcohol in ALDH2*2/*2 knock-in mice exacerbates the pathogenesis of AD-like symptoms. Therefore, ALDH2 polymorphism and alcohol consumption likely play an important role in the onset and progression of AD. Here, we review the data on the relationship between ALDH2 polymorphism, alcohol, and AD, and summarize what is currently known about the role of the common ALDH2 inactivating mutation, ALDH2*2, and alcohol in the onset and progression of AD.
Journal Article
Apolipoprotein E4 allele is genetically associated with risk of the short- and medium-term postoperative cognitive dysfunction: A meta-analysis and trial sequential analysis
2023
The aim of systematic review and meta-analysis was to investigate whether APOE4 was associated with postoperative neurologic dysfunction occurrence in short- or medium-term among surgical patients and to study the potential genetic association among these two entities. We searched electronic databases for reserch studies to evaluate the association of APOE4 with postoperative delirium (POD) or short- and medium term postoperative cognitive dysfunction (POCD). Twenty-two trials (16 prospective and six retrospective) with 6734 patients were included. APOE4 alleles was shown significantly associated with POCD within 1 week (odds ratio, OR, 1.89, 95% confidence interval, CI, 1.36 to 2.6278, p < 0.01) in the random-effects model. A significant association was also noted between APOE4 and POCD in medium-term, 1–3 months, after surgery (OR: 1.67, 95% CI: 1.003–2.839, p = 0.049). However, APOE4 was not significantly associated with POCD 1 year after surgery (OR: 0.98, 95% CI: 0.57–1.70, p = 0.9449) and POD (OR: 1.28, 95% CI: 0.85–1.91, p = 0.23). In conclusion, APOE4 alleles was genetically associated with short- and medium-term postoperative neurological dysfunction and future screening or preventive strategies derived is highly potential to improve outcomes.
Journal Article
Effects of aerobic and resistance exercise on glycosylated hemoglobin (HbA1c) concentrations in non-diabetic Taiwanese individuals based on the waist-hip ratio
2022
Glycosylated hemoglobin (HbA1c) reflects the average blood sugar over the past eight to twelve weeks. Several demographic and lifestyle factors are known to affect HbA1c levels. We evaluated the association of HbA1c with aerobic and resistance exercise in non-diabetic Taiwanese adults based on the waist-hip ratio (WHR).
We conducted this study based on TWB data collected from 90,958 individuals between 2008 and 2019. We estimated the Beta (β) coefficient and 95% confidence intervals (CI) for HbA1c using multivariate regression models.
Based on the multivariate analysis, lower HbA1c levels were associated with both resistance exercise (β-coefficient = -0.027, 95% CI -0.037 to -0.017) and aerobic exercise (β-coefficient = 0.018, 95% CI, -0.023 to -0.013). Higher HbA1c levels were associated with abnormal WHR compared to normal WHR (β-coefficient = 0.091, 95% CI, 0.086 to 0.096). We detected an interaction between exercise and WHR (p for interaction = 0.0181). To determine the magnitude of the interaction, we performed additional analyses (with the reference group being 'abnormal WHR with no exercise') and observed substantial decreases in HbA1c regardless of the WHR and exercise category. However, the largest reduction occurred in the 'normal WHR and resistance exercise' group (β = -0.121, 95% CI, -0.132 to -0.109).
We found that normal resistance exercise, coupled with a normal WHR was significantly associated with lower HbA1c levels among non-diabetic individuals in Taiwan.
Journal Article
A common East-Asian ALDH2 mutation causes metabolic disorders and the therapeutic effect of ALDH2 activators
2023
Obesity and type 2 diabetes have reached pandemic proportion. ALDH2 (acetaldehyde dehydrogenase 2, mitochondrial) is the key metabolizing enzyme of acetaldehyde and other toxic aldehydes, such as 4-hydroxynonenal. A missense Glu504Lys mutation of the
ALDH2
gene is prevalent in 560 million East Asians, resulting in reduced ALDH2 enzymatic activity. We find that male
Aldh2
knock-in mice mimicking human Glu504Lys mutation were prone to develop diet-induced obesity, glucose intolerance, insulin resistance, and fatty liver due to reduced adaptive thermogenesis and energy expenditure. We find reduced activity of ALDH2 of the brown adipose tissue from the male
Aldh2
homozygous knock-in mice. Proteomic analyses of the brown adipose tissue from the male
Aldh2
knock-in mice identifies increased 4-hydroxynonenal-adducted proteins involved in mitochondrial fatty acid oxidation and electron transport chain, leading to markedly decreased fatty acid oxidation rate and mitochondrial respiration of brown adipose tissue, which is essential for adaptive thermogenesis and energy expenditure.
AD-9308
is a water-soluble, potent, and highly selective ALDH2 activator.
AD-9308
treatment ameliorates diet-induced obesity and fatty liver, and improves glucose homeostasis in both male
Aldh2
wild-type and knock-in mice. Our data highlight the therapeutic potential of reducing toxic aldehyde levels by activating ALDH2 for metabolic diseases.
A common East Asian-specific defect of an alcohol metabolizing enzyme (ALDH2) causes glucose abnormality, obesity, and fatty liver. Here, the authors show an ALDH2 activator can treat these metabolic disorders in mice.
Journal Article
Alda-1 is an agonist and chemical chaperone for the common human aldehyde dehydrogenase 2 variant
by
Perez-Miller, Samantha
,
Younus, Hina
,
Hurley, Thomas D
in
631/337/470
,
631/45/173
,
631/92/613
2010
Alcohol dehydrogenase (ALDH2) is involved in metabolising ethanol. A single point mutation leads to Asian alcohol-induced flushing syndrome and is linked to increased cardiac damage following a heart attack. The small molecule Alda-1 restores normal activity to the mutant, and structures of Alda-1 bound to mutant ALDH2 and the wild type now explain this effect.
In approximately one billion people, a point mutation inactivates a key detoxifying enzyme, aldehyde dehydrogenase (ALDH2). This mitochondrial enzyme metabolizes toxic biogenic and environmental aldehydes, including the endogenously produced 4-hydroxynonenal (4HNE) and the environmental pollutant acrolein, and also bioactivates nitroglycerin. ALDH2 is best known, however, for its role in ethanol metabolism. The accumulation of acetaldehyde following the consumption of even a single alcoholic beverage leads to the Asian alcohol-induced flushing syndrome in
ALDH2*2
homozygotes. The
ALDH2*2
allele is semidominant, and heterozygotic individuals show a similar but less severe phenotype. We recently identified a small molecule, Alda-1, that activates wild-type ALDH2 and restores near-wild-type activity to ALDH2*2. The structures of Alda-1 bound to ALDH2 and ALDH2*2 reveal how Alda-1 activates the wild-type enzyme and how it restores the activity of ALDH2*2 by acting as a structural chaperone.
Journal Article
Pharmacological recruitment of aldehyde dehydrogenase 3A1 (ALDH3A1) to assist ALDH2 in acetaldehyde and ethanol metabolism in vivo
by
Chen, Che-Hong
,
Cruz, Leslie A.
,
Mochly-Rosen, Daria
in
acetaldehyde
,
alcoholic beverages
,
aldehyde dehydrogenase
2015
Correcting a genetic mutation that leads to a loss of function has been a challenge. One such mutation is in aldehyde dehydrogenase 2 (ALDH2), denoted ALDH2*2. This mutation is present in ∼0.6 billion East Asians and results in accumulation of toxic acetaldehyde after consumption of ethanol. To temporarily increase metabolism of acetaldehyde in vivo, we describe an approach in which a pharmacologic agent recruited another ALDH to metabolize acetaldehyde. We focused on ALDH3A1, which is enriched in the upper aerodigestive track, and identified Alda-89 as a small molecule that enables ALDH3A1 to metabolize acetaldehyde. When given together with the ALDH2-specific activator, Alda-1, Alda-89 reduced acetaldehyde-induced behavioral impairment by causing a rapid reduction in blood ethanol and acetaldehyde levels after acute ethanol intoxication in both wild-type and ALDH2-deficient, ALDH2*1/*2, heterozygotic knock-in mice. The use of a pharmacologic agent to recruit an enzyme to metabolize a substrate that it usually does not metabolize may represent a novel means to temporarily increase elimination of toxic agents in vivo .
Significance About 560 million East Asians have an impaired ability to eliminate acetaldehyde because of a point mutation in an enzyme called aldehyde dehydrogenase 2 (ALDH2). Humans with this mutation have ∼20-fold higher blood acetaldehyde levels than those with normal enzyme activity after consuming one to two units of alcoholic beverages. Because acetaldehyde is a potent carcinogen and causes behavioral impairment, its accumulation is a health risk. We identified a pharmacologic agent that recruits ALDH3A1, a closely related enzyme, to compensate for a loss of ability of ALDH2 to metabolize acetaldehyde. Pharmacologic agents that alter substrate specificity of an enzyme have not yet been described and may have wide clinical application in treating patients with impaired ability to detoxify toxic substances.
Journal Article