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1.
Anal Chem ; 96(13): 5307-5314, 2024 04 02.
Article in English | MEDLINE | ID: mdl-38504497

ABSTRACT

Gene doping involves the misuse of genetic materials to alter an athlete's performance, which is banned at all times in both human and equine sports. Quantitative polymerase chain reaction (qPCR) assays have been used to control the misuse of transgenes in equine sports. Our laboratory recently developed and implemented duplex as well as multiplex qPCR assays for transgenes detection. To further advance gene doping control, we have developed for the first time a sensitive and definitive PCR-liquid chromatography high-resolution tandem mass spectrometry (PCR-LC-HRMS/MS) method for transgene detection with an estimated limit of detection of below 100 copies/mL for the human erythropoietin (hEPO) transgene in equine plasma. The method involved magnetic-glass-particle-based extraction of DNA from equine plasma prior to PCR amplification with 2'-deoxyuridine 5'-triphosphate (dUTP) followed by treatments with uracil DNA glycosylase and hot piperidine for selective cleavage to give small oligonucleotide fragments. The resulting DNA fragments were then analyzed by LC-HRMS/MS. The applicability of this method has been demonstrated by the successful detection of hEPO transgene in a blood sample collected from a gelding (castrated male horse) that had been administered the transgene. This novel approach not only serves as a complementary method for transgene detection but also paves the way for developing a generic PCR-LC-HRMS/MS method for the detection of multiple transgenes.


Subject(s)
Doping in Sports , Erythropoietin , Horses , Animals , Humans , Male , Tandem Mass Spectrometry/methods , Doping in Sports/prevention & control , Chromatography, Liquid/methods , Erythropoietin/genetics , Transgenes , DNA , Polymerase Chain Reaction
2.
Clin Exp Pharmacol Physiol ; 51(1): 30-39, 2024 01.
Article in English | MEDLINE | ID: mdl-37933553

ABSTRACT

Spinocerebellar ataxia 3 (SCA3) is an incurable, neurodegenerative genetic disorder that leads to progressive cerebellar ataxia and other parkinsonian-like pathologies because of loss of cerebellar neurons. The role of an expanded polyglutamine aggregate on neural progenitor cells is unknown. Here, we show that SCA3 patient-specific induced neural progenitor cells (iNPCs) exhibit proliferative defects. Moreover, SCA3 iNPCs have reduced autophagic expression compared to control. Furthermore, although SCA3 iNPCs continue to proliferate, they do not survive subsequent passages compared to control iNPCs, indicating the likelihood that SCA3 iNPCs undergo rapid senescence. Exposure to interleukin-4 (IL-4), a type 2 cytokine produced by immune cells, resulted in an observed increase in expression of autophagic programs and a reduction in the proliferation defect observed in SCA3 iNPCs. Our results indicate a previously unobserved role of SCA3 disease ontology on the neural stem cell pool and a potential therapeutic strategy using IL-4 to ameliorate or delay disease pathology in the SCA3 neural progenitor cell population.


Subject(s)
Machado-Joseph Disease , Neural Stem Cells , Humans , Machado-Joseph Disease/genetics , Machado-Joseph Disease/metabolism , Machado-Joseph Disease/pathology , Interleukin-4 , Cytokines/metabolism , STAT6 Transcription Factor/metabolism
3.
Rheumatology (Oxford) ; 62(4): 1501-1510, 2023 04 03.
Article in English | MEDLINE | ID: mdl-36066415

ABSTRACT

OBJECTIVES: The effects of sodium-glucose cotransporter 2 inhibitors (SGLT2I) vs dipeptidyl peptidase-4 inhibitors (DPP4I) on the risk of new-onset gout remains unknown. This study aims to compare the effects of SGLT2I against DPP4I on gout risks. METHODS: This was a retrospective population-based cohort study of patients with type-2 diabetes mellitus treated with SGLT2I or DPP4I between 1 January 2015 and 31 December 2020 in Hong Kong. The study outcomes are new-onset gout and all-cause mortality. Propensity score matching (1:1 ratio) between SGLT2I and DPP4I was performed. Univariable and multivariable Cox regression models were conducted. Competing risks models and multiple approaches based on the propensity score were applied. RESULTS: This study included 43 201 patients [median age: 63.23 years old (Interquartile range, IQR): 55.21-71.95, 53.74% males; SGLT2I group: n = 16 144; DPP4I group: n = 27 057] with a median follow-up of 5.59 years (IQR: 5.27-5.81 years) since initial drug exposure. The incidence rate of developing gout [Incidence rate (IR): 2.5; 95% CI: 2.2, 2.9] among SGLT2I users was significantly lower than DPP4I users (IR: 5.2; 95% CI: 4.8, 5.8). SGLT2I was associated with 51% lower risks of gout (HR: 0.49; 95% CI: 0.42, 0.58; P-value < 0.0001) and 51% lower risks of all-cause mortality (HR: 0.49; 95% CI: 0.42, 0.58; P-value < 0.0001) after adjusting for significant demographics, past comorbidities, medications and laboratory results. The results remained consistent on competing risk and other propensity score approaches. CONCLUSIONS: SGLT2I use was associated with lower risks of new gout diagnosis compared with DPP4I use.


Subject(s)
Diabetes Mellitus, Type 2 , Dipeptidyl-Peptidase IV Inhibitors , Gout , Sodium-Glucose Transporter 2 Inhibitors , Male , Humans , Middle Aged , Female , Dipeptidyl-Peptidase IV Inhibitors/therapeutic use , Dipeptidyl-Peptidase IV Inhibitors/pharmacology , Hypoglycemic Agents/therapeutic use , Sodium-Glucose Transporter 2 Inhibitors/therapeutic use , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Dipeptidyl Peptidase 4/therapeutic use , Cohort Studies , Retrospective Studies , Sodium-Glucose Transporter 2/therapeutic use , Diabetes Mellitus, Type 2/complications , Gout/drug therapy , Gout/complications
4.
Cardiovasc Drugs Ther ; 37(3): 561-569, 2023 06.
Article in English | MEDLINE | ID: mdl-35142921

ABSTRACT

OBJECTIVE: To compare the effects of sodium-glucose cotransporter 2 inhibitors (SGLT2Is) and dipeptidyl peptidase-4 inhibitors (DPP4Is) on adverse outcomes in diabetic patients in Hong Kong. METHODS: This was a retrospective population-based cohort study of type 2 diabetes mellitus patients (n = 72,746) treated with SGLT2I or DPP4I between January 1, 2015, and December 31, 2020, in Hong Kong. Patients with exposure to both DPP4I and SGLT2I therapy, without complete demographics or mortality data, or who had prior atrial fibrillation (AF) were excluded. The study outcomes were new-onset AF, stroke/transient ischemic attack, cardiovascular mortality and all-cause mortality. Propensity score matching (1:1 ratio) between SGLT2I and DPP4I users was performed. RESULTS: The unmatched study cohort included 21,713 SGLT2I users and 39,510 DPP4I users (total: n = 61,233 patients; 55.37% males, median age: 62.7 years [interquartile range (IQR): 54.6-71.9 years]). Over a median follow-up of 2030 (IQR: 1912-2117) days, 2496 patients (incidence rate [IR]: 4.07%) developed new-onset AF, 2179 patients (IR: 3.55%) developed stroke/transient ischemic attack, 1963 (IR: 3.20%) died from cardiovascular causes and 6607 patients (IR: 10.79%) suffered from all-cause mortality. After propensity score matching (SGLT2I: n = 21,713; DPP4I: n = 21,713), SGLT2I users showed lower incidence of new-onset AF (1.96% vs. 2.78%, standardized mean difference [SMD] = 0.05), stroke (1.80% vs. 3.52%, SMD = 0.11), cardiovascular mortality (0.47% vs. 1.56%, SMD = 0.11) and all-cause mortality (2.59% vs. 7.47%, SMD = 0.22) compared to DPP4I users. Cox regression found that SGLT2I users showed lower risk of new-onset AF (hazard ratio [HR]: 0.68, 95% confidence interval [CI]: [0.56, 0.83], P = 0.0001), stroke (HR: 0.64, 95% CI: [0.53, 0.79], P < 0.0001), cardiovascular mortality (HR: 0.39, 95% CI: [0.27, 0.56], P < 0.0001) and all-cause mortality (HR: 0.44, 95% CI: [0.37, 0.51], P < 0.0001) after adjusting for significant demographics, past comorbidities, medications and laboratory tests. CONCLUSIONS: Based on real-world data of type 2 diabetic patients in Hong Kong, SGLT2I use was associated with lower risk of incident AF, stroke/transient ischemic attack, and cardiovascular and all-cause mortality outcomes compared to DPP4I use.


Subject(s)
Atrial Fibrillation , Diabetes Mellitus, Type 2 , Dipeptidyl-Peptidase IV Inhibitors , Ischemic Attack, Transient , Sodium-Glucose Transporter 2 Inhibitors , Stroke , Male , Humans , Middle Aged , Female , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/complications , Dipeptidyl-Peptidase IV Inhibitors/adverse effects , Cohort Studies , Retrospective Studies , Atrial Fibrillation/diagnosis , Atrial Fibrillation/drug therapy , Atrial Fibrillation/epidemiology , Propensity Score , Hong Kong/epidemiology , Sodium-Glucose Transporter 2 Inhibitors/adverse effects , Hypoglycemic Agents/therapeutic use , Stroke/diagnosis , Stroke/epidemiology , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/therapeutic use , Glucose , Sodium/therapeutic use
5.
Sci Technol Adv Mater ; 24(1): 2167466, 2023.
Article in English | MEDLINE | ID: mdl-36846525

ABSTRACT

Gels with high drug release sustainability and intrinsic antibacterial properties are of high practical potential for cutaneous drug administration, particularly for wound care and skin disease treatment. This study reports the generation and characterization of gels formed by 1,5-pentanedial-mediated crosslinking between chitosan and lysozyme for cutaneous drug delivery. Structures of the gels are characterized by using scanning electron microscopy, X-ray diffractometry and Fourier-transform infrared spectroscopy. An increase in the mass percentage of lysozyme leads to an increase in the swelling ratio and erosion susceptibility of the resulting gels. The drug delivery performance of the gels can be changed simply by manipulating the chitosan/lysozyme mass-to-mass ratio, with an increase in the mass percentage of lysozyme leading to a decline in the encapsulation efficiency and drug release sustainability of the gels. Not only do all gels tested in this study show negligible toxicity in NIH/3T3 fibroblasts, they also demonstrate intrinsic antibacterial effects against both Gram-negative and Gram-positive bacteria, with the magnitude of the effect being positively related to the mass percentage of lysozyme. All these warrant the gels to be further developed as intrinsically antibacterial carriers for cutaneous drug administration.

6.
Rev Cardiovasc Med ; 23(8): 276, 2022 Aug.
Article in English | MEDLINE | ID: mdl-39076628

ABSTRACT

Background: This study examined the clinical characteristics, genetic basis, healthcare utilisation and costs of catecholaminergic ventricular tachycardia (CPVT) patients from a Chinese city. Methods: This was a territory-wide retrospective cohort study of consecutive CPVT patients at public hospitals or clinics in Hong Kong. Healthcare resource utilisation for accident and emergency (A&E), inpatient and outpatient attendances were analysed over 19 years (2001-2019) followed by calculations of annualised costs (in USD). Results: Sixteen patients with a median presentation age (interquartile range (IQR) of 11 (9-14) years old) were included. Fifteen patients (93.8%) were initially symptomatic. Ten patients had both premature ventricular complexes (PVCs) and ventricular tachycardia/fibrillation (VT/VF). One patient had PVCs without VT/VF. Genetic tests were performed on 14 patients (87.5%). Eight (57.1%) tested positive for the ryanodine receptor 2 (RyR2) gene. Seven variants have been described elsewhere (c.14848G > A, c.12475C > A, c.7420A > G, c.11836G > A, c.14159T > C, c.10046C > T and c.7202G > A). c.14861C > G is a novel RyR2 variant not been reported outside this cohort. Patients were treated with beta-blockers (n = 16), amiodarone (n = 3) and verapamil (n = 2). Sympathectomy (n = 8) and implantable-cardioverter defibrillator implantation (n = 3) were performed. Over a median follow-up of 13.3 years (IQR: 8.4-18.1) years, six patients exhibited incident VT/VF. At the patient level, the median (IQR) annualised costs for A&E, inpatient and outpatient attendances were $ 66 (40-95), $ 10521 (5240-66887) and $ 791 (546-1105), respectively. Conclusions: All patients presented before the age of 19. The yield of genetic testing was 57%. The most expensive attendance type was inpatient stays, followed by outpatients and A&E attendances.

7.
Rev Cardiovasc Med ; 23(7): 231, 2022 Jul.
Article in English | MEDLINE | ID: mdl-39076921

ABSTRACT

Background: Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a hereditary disease characterized by fibrofatty infiltration of the right ventricular myocardium that predisposes affected patients to malignant ventricular arrhythmias, dual-chamber cardiac failure and sudden cardiac death (SCD). The present study aims to investigate the risk of detrimental cardiovascular events in an Asian population of ARVC/D patients, including the incidence of malignant ventricular arrhythmias, new-onset heart failure with reduced ejection fraction (HFrEF), as well as long-term mortality. Methods and Results: This was a territory-wide retrospective cohort study of patients diagnosed with ARVC/D between 1997 and 2019 in Hong Kong. This study consisted of 109 ARVC/D patients (median age: 61 [46-71] years; 58% male). Of these, 51 and 24 patients developed incident VT/VF and new-onset HFrEF, respectively. Five patients underwent cardiac transplantation, and 14 died during follow-up. Multivariate Cox regression identified prolonged QRS duration as a predictor of VT/VF (p < 0.05). Female gender, prolonged QTc duration, the presence of epsilon waves and T-wave inversion (TWI) in any lead except aVR/V1 predicted new-onset HFrEF (p < 0.05). The presence of epsilon waves, in addition to the parameters of prolonged QRS duration and worsening ejection fraction predicted all-cause mortality (p < 0.05). Clinical scores were developed to predict incident VT/VF, new-onset HFrEF and all-cause mortality, and all were significantly improved by machine learning techniques. Conclusions: Clinical and electrocardiographic parameters are important for assessing prognosis in ARVC/D patients and should in turn be used in tandem to aid risk stratification in the hospital setting.

8.
J Natl Compr Canc Netw ; 20(6): 674-682.e15, 2022 06.
Article in English | MEDLINE | ID: mdl-35714677

ABSTRACT

BACKGROUND: The aim of this study was to compare the risks of new-onset prostate cancer between metformin and sulfonylurea users with type 2 diabetes mellitus (T2DM). METHODS: This population-based retrospective cohort study included male patients with T2DM presenting to public hospitals/clinics in Hong Kong between January 1, 2000, and December 31, 2009. We only included patients prescribed either, but not both, metformin or sulfonylurea. All patients were followed up until December 31, 2019. The primary outcome was new-onset prostate cancer and the secondary outcome was all-cause mortality. One-to-one propensity score matching was performed between metformin and sulfonylurea users based on demographics, comorbidities, antidiabetic and cardiovascular medications, fasting blood glucose level, and hemoglobin A1c level. Subgroup analyses based on age and use of androgen deprivation therapy were performed. RESULTS: The final study cohort consisted of 25,695 metformin users (mean [SD] age, 65.2 [11.8] years) and 25,695 matched sulfonylurea users (mean [SD] age, 65.3 [11.8] years) with a median follow-up duration of 119.6 months (interquartile range, 91.7-139.6 months) after 1:1 propensity score matching of 66,411 patients. Metformin users had lower risks of new-onset prostate cancer (hazard ratio, 0.80; 95% CI, 0.69-0.93; P=.0031) and all-cause mortality (hazard ratio, 0.89; 95% CI, 0.86-0.92; P<.0001) than sulfonylurea users. Metformin use was more protective against prostate cancer but less protective against all-cause mortality in patients aged <65 years (P for trend <.0001 for both) compared with patients aged ≥65 years. Metformin users had lower risk of all-cause mortality than sulfonylurea users, regardless of the use of androgen deprivation therapy (P for trend <.0001) among patients who developed prostate cancer. CONCLUSIONS: Metformin use was associated with significantly lower risks of new-onset prostate cancer and all-cause mortality than sulfonylurea use in male patients with T2DM.


Subject(s)
Diabetes Mellitus, Type 2 , Metformin , Prostatic Neoplasms , Aged , Androgen Antagonists/therapeutic use , Androgens/therapeutic use , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/epidemiology , Humans , Male , Metformin/adverse effects , Propensity Score , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/epidemiology , Prostatic Neoplasms/etiology , Retrospective Studies , Sulfonylurea Compounds/adverse effects
9.
Crit Rev Food Sci Nutr ; 62(26): 7319-7335, 2022.
Article in English | MEDLINE | ID: mdl-33905265

ABSTRACT

Quercetin is a flavonoid present in a wide variety of plant resources. Over the years, extensive efforts have been devoted to examining the potential biological effects of quercetin and to manipulating the chemical and physical properties of the flavonoid. However, limited studies have reviewed the opportunities and challenges of using quercetin in the development of functional foods. To address this necessity, in this review; we foremost present an overview of the chemical properties and stability of quercetin in food products followed by a detailed discussion of various strategies that enhance its oral bioavailability. We further highlight the areas to be practically considered during development of quercetin-based functional foods. By revisiting the current status of applied research on quercetin, it is anticipated that useful insights enabling research on quercetin can be potentially translated into practical applications in food product development.


Subject(s)
Functional Food , Quercetin , Biological Availability , Flavonoids
10.
Crit Rev Food Sci Nutr ; 62(19): 5140-5166, 2022.
Article in English | MEDLINE | ID: mdl-33559482

ABSTRACT

The last decide has witnessed a growing research interest in the role of dietary phytochemicals in influencing the gut microbiota. On the other hand, recent evidence reveals that dietary phytochemicals exhibit properties of preventing and tackling symptoms of Alzheimer's disease, which is a neurodegenerative disease that has also been linked with the status of the gut microbiota over the last decade. Till now, little serious discussions, however, have been made to link recent understanding of Alzheimer's disease, dietary phytochemicals and the gut microbiota together and to review the roles played by phytochemicals in gut dysbiosis induced pathologies of Alzheimer's disease. Deciphering these connections can provide insights into the development and future use of dietary phytochemicals as anti-Alzheimer drug candidates. This review aims at presenting latest evidence in the modulating role of phytochemicals in the gut microbiota and its relevance to Alzheimer's disease and summarizing the mechanisms behind the modulative activities. Limitations of current research in this field and potential directions will also be discussed for future research on dietary phytochemicals as anti-Alzheimer agents.


Subject(s)
Alzheimer Disease , Gastrointestinal Microbiome , Neurodegenerative Diseases , Alzheimer Disease/drug therapy , Alzheimer Disease/prevention & control , Dysbiosis/drug therapy , Humans , Phytochemicals/pharmacology , Phytochemicals/therapeutic use
11.
Proc Natl Acad Sci U S A ; 116(52): 26614-26624, 2019 Dec 26.
Article in English | MEDLINE | ID: mdl-31822610

ABSTRACT

Epstein-Barr nuclear antigen 1 (EBNA1) plays a vital role in the maintenance of the viral genome and is the only viral protein expressed in nearly all forms of Epstein-Barr virus (EBV) latency and EBV-associated diseases, including numerous cancer types. To our knowledge, no specific agent against EBV genes or proteins has been established to target EBV lytic reactivation. Here we report an EBNA1- and Zn2+-responsive probe (ZRL5P4) which alone could reactivate the EBV lytic cycle through specific disruption of EBNA1. We have utilized the Zn2+ chelator to further interfere with the higher order of EBNA1 self-association. The bioprobe ZRL5P4 can respond independently to its interactions with Zn2+ and EBNA1 with different fluorescence changes. It can selectively enter the nuclei of EBV-positive cells and disrupt the oligomerization and oriP-enhanced transactivation of EBNA1. ZRL5P4 can also specifically enhance Dicer1 and PML expression, molecular events which had been reported to occur after the depletion of EBNA1 expression. Importantly, we found that treatment with ZRL5P4 alone could reactivate EBV lytic induction by expressing the early and late EBV lytic genes/proteins. Lytic induction is likely mediated by disruption of EBNA1 oligomerization and the subsequent change of Dicer1 expression. Our probe ZRL5P4 is an EBV protein-specific agent that potently reactivates EBV from latency, leading to the shrinkage of EBV-positive tumors, and our study also suggests the association of EBNA1 oligomerization with the maintenance of EBV latency.

12.
Int J Mol Sci ; 23(11)2022 Jun 04.
Article in English | MEDLINE | ID: mdl-35682975

ABSTRACT

Polymeric films for active food packaging have been playing an important role in food preservation due to favorable properties including high structural flexibility and high property tunability. Over the years, different polymeric active packaging films have been developed. Many of them have found real applications in food production. This article reviews, using a practical perspective, the principles of designing polymeric active packaging films. Different factors to be considered during materials selection and film generation are delineated. Practical considerations for the use of the generated polymeric films in active food packaging are also discussed. It is hoped that this article cannot only present a snapshot of latest advances in the design and optimization of polymeric active food packaging films, but insights into film development to achieve more effective active food packaging can be attained for future research.


Subject(s)
Food Packaging , Polymers , Food Preservation
13.
Am J Hum Genet ; 103(2): 276-287, 2018 08 02.
Article in English | MEDLINE | ID: mdl-30075114

ABSTRACT

Primary hypertension is a major risk factor for ischemic heart disease, stroke, and chronic kidney disease. Insights obtained from the study of rare Mendelian forms of hypertension have been invaluable in elucidating the mechanisms causing primary hypertension and development of antihypertensive therapies. Endothelial cells play a key role in the regulation of blood pressure; however, a Mendelian form of hypertension that is primarily due to endothelial dysfunction has not yet been described. Here, we show that the urea cycle disorder, argininosuccinate lyase deficiency (ASLD), can manifest as a Mendelian form of endothelial-dependent hypertension. Using data from a human clinical study, a mouse model with endothelial-specific deletion of argininosuccinate lyase (Asl), and in vitro studies in human aortic endothelial cells and induced pluripotent stem cell-derived endothelial cells from individuals with ASLD, we show that loss of ASL in endothelial cells leads to endothelial-dependent vascular dysfunction with reduced nitric oxide (NO) production, increased oxidative stress, and impaired angiogenesis. Our findings show that ASLD is a unique model for studying NO-dependent endothelial dysfunction in human hypertension.


Subject(s)
Argininosuccinate Lyase/genetics , Argininosuccinic Aciduria/genetics , Endothelial Cells/pathology , Hypertension/genetics , Adolescent , Animals , Blood Pressure/genetics , Cells, Cultured , Child , Disease Models, Animal , Endothelium, Vascular/pathology , Female , Humans , Male , Mice , Mice, Transgenic , Neovascularization, Pathologic/genetics , Nitric Oxide/genetics , Oxidative Stress/genetics , Urea Cycle Disorders, Inborn/genetics
14.
Pharmacol Res ; 169: 105681, 2021 07.
Article in English | MEDLINE | ID: mdl-34019979

ABSTRACT

Reports of the beneficial roles of butyrate in cardiovascular diseases, such as atherosclerosis and ischemic stroke, are becoming increasingly abundant. However, the mechanisms of its bioactivities remain largely unknown. In this study, we explored the effects of butyrate on endothelial dysfunction and its potential underlying mechanism. In our study, ApoE-/- mice were fed with high-fat diet (HFD) for ten weeks to produce atherosclerosis models and concurrently treated with or without sodium butyrate daily. Thoracic aortas were subsequently isolated from C57BL/6 wild-type (WT), PPARδ-/-, endothelial-specific PPARδ wild-type (EC-specific PPARδ WT) and endothelial-specific PPARδ knockout (EC-specific PPARδ KO) mice were stimulated with interleukin (IL)-1ß with or without butyrate ex vivo. Our results demonstrated that butyrate treatment rescued the impaired endothelium-dependent relaxations (EDRs) in thoracic aortas of HFD-fed ApoE-/- mice. Butyrate also rescued impaired EDRs in IL-1ß-treated thoracic aorta ring ex vivo. Global and endothelial-specific knockout of PPARδ eliminated the protective effects of butyrate against IL-1ß-induced impairment to EDRs. Butyrate abolished IL-1ß-induced reactive oxygen species (ROS) production in endothelial cells while the inhibitory effect was incapacitated by genetic deletion of PPARδ or pharmacological inhibition of PPARδ. IL-1ß increased NADPH oxidase 2 (NOX2) mRNA and protein expressions in endothelial cells, which were prevented by butyrate treatment, and the effects of butyrate were blunted following pharmacological inhibition of PPARδ. Importantly, butyrate treatment upregulated the miR-181b expression in atherosclerotic aortas and IL-1ß-treated endothelial cells. Moreover, transfection of endothelial cells with miR-181b inhibitor abolished the suppressive effects of butyrate on NOX2 expressions and ROS generation in endothelial cells. To conclude, butyrate prevents endothelial dysfunction in atherosclerosis by reducing endothelial NOX2 expression and ROS production via the PPARδ/miR-181b pathway.


Subject(s)
Butyrates/pharmacology , Endothelium, Vascular/drug effects , MicroRNAs/metabolism , PPAR gamma/metabolism , Signal Transduction/drug effects , Animals , Blotting, Western , Diet, High-Fat , Endothelium, Vascular/metabolism , Endothelium, Vascular/physiology , Mice , Mice, Inbred C57BL , Mice, Knockout , Muscle Relaxation/drug effects , Reactive Oxygen Species/metabolism , Real-Time Polymerase Chain Reaction
15.
BMC Endocr Disord ; 21(1): 94, 2021 May 04.
Article in English | MEDLINE | ID: mdl-33947391

ABSTRACT

INTRODUCTION: Recent studies have reported that HbA1c and lipid variability is useful for risk stratification in diabetes mellitus. The present study evaluated the predictive value of the baseline, subsequent mean of at least three measurements and variability of HbA1c and lipids for adverse outcomes. METHODS: This retrospective cohort study consists of type 1 and type 2 diabetic patients who were prescribed insulin at outpatient clinics of Hong Kong public hospitals, from 1st January to 31st December 2009. Standard deviation (SD) and coefficient of variation were used to measure the variability of HbA1c, total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglyceride. The primary outcome is all-cause mortality. Secondary outcomes were diabetes-related complications. RESULT: The study consists of 25,186 patients (mean age = 63.0, interquartile range [IQR] of age = 15.1 years, male = 50%). HbA1c and lipid value and variability were significant predictors of all-cause mortality. Higher HbA1c and lipid variability measures were associated with increased risks of neurological, ophthalmological and renal complications, as well as incident dementia, osteoporosis, peripheral vascular disease, ischemic heart disease, atrial fibrillation and heart failure (p <  0.05). Significant association was found between hypoglycemic frequency (p <  0.0001), HbA1c (p <  0.0001) and lipid variability against baseline neutrophil-lymphocyte ratio (NLR). CONCLUSION: Raised variability in HbA1c and lipid parameters are associated with an elevated risk in both diabetic complications and all-cause mortality. The association between hypoglycemic frequency, baseline NLR, and both HbA1c and lipid variability implicate a role for inflammation in mediating adverse outcomes in diabetes, but this should be explored further in future studies.


Subject(s)
Diabetes Complications/diagnosis , Diabetes Mellitus/diagnosis , Machine Learning , Adult , Aged , Blood Glucose/analysis , Blood Glucose/metabolism , Computer Simulation , Diabetes Complications/blood , Diabetes Complications/mortality , Diabetes Mellitus/blood , Diabetes Mellitus/mortality , Female , Glycated Hemoglobin/analysis , Glycated Hemoglobin/metabolism , Hong Kong/epidemiology , Humans , Lipids/analysis , Lipids/blood , Male , Middle Aged , Prognosis , Retrospective Studies , Risk Factors , Survival Analysis
16.
Clin Exp Pharmacol Physiol ; 48(1): 129-136, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32852093

ABSTRACT

OBJECTIVE: Interleukin-4 (IL-4) signalling pathways regulate the activity of macrophages, enhance their proteolytic capacity and drive resolution of inflammation during tissue repair. The aim of this study was to examine whether IL-4 can enhance phagocytosis of necrotic cells and elucidate the molecular mechanisms. METHODS: Phagocytosis of necrotic thymocytes by RAW264.7 cells, a macrophage cell line, with or without IL-4 treatment, was determined by flow cytometry. Protein expression was determined by western blot analysis. RESULTS: The phagocytosis index was significantly increased by IL-4 (10 ng/mL). IL-4-enhanced phagocytosis was mediated by upregulation of scavenger receptor CD36. STAT6 activation is required for IL-4-mediated phagocytosis. CONCLUSIONS: Interleukin-4 can accelerate cell debris clearance by stimulating expression of CD36, which requires downstream STAT6 activation. Its beneficial effects on driving tissue repair and regeneration should be explored in future studies.

17.
Clin Exp Pharmacol Physiol ; 48(8): 1043-1058, 2021 08.
Article in English | MEDLINE | ID: mdl-33987869

ABSTRACT

Crocodile blood has long been used as a traditional medicine in many Asian countries to treat diseases such as asthma, allergies, and many others. Yet, only recently has the safety and effectiveness of using crocodile blood as a medicine been examined using modern scientific methods; with both conserved and novel active components identified from crocodile blood. Further in vitro and in vivo investigations found that crocodile blood can have a wide range of beneficial effects, including antimicrobial, antiviral, anti-oxidative, anti-inflammatory, antitumour effects, anti-anaemia, and enhancement of wound healing. A systematic research of literature published in English-language journals up to April 2020 was conducted in PubMed, Google Scholar, and Web of Science. Based on the biological and chemical knowledge of crocodile immunity and crocodile blood, this article aims to: provide a critical review on the proposed properties of crocodile blood, identify the knowledge gap and offer some insights for future investigations regarding the use of crocodile blood as a medication or dietary supplement.


Subject(s)
Alligators and Crocodiles , Wound Healing , Animals , Anti-Bacterial Agents
18.
Int J Mol Sci ; 22(5)2021 Feb 28.
Article in English | MEDLINE | ID: mdl-33671052

ABSTRACT

The purpose of this work was to fractionate the complex exopolysaccharide (EPS) from a medicinal fungus Ophiocordyceps sinensis Cs-HK1 based on the molecular weight (MW) range and to assess the in vitro anti-inflammatory activity of different EPS fractions in THP-1 cell culture. The lower MW fraction (EPS-LM-1) showed a much higher anti-inflammatory activity. EPS-LM-1 was identified as a heteropolysaccharide consisting of mannose, glucose, and galactose residues with an average MW of 360 kDa. EPS-LM-1 significantly inhibited the lipopolysaccharide-induced inflammatory responses with the effective concentrations for 50% inhibition below 5 µg/mL on a few major proinflammatory markers. With such a notable in vitro anti-inflammatory activity, EPS-LM-1 is a promising candidate for the development of a new anti-inflammation therapy.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Cordyceps/metabolism , Fermentation , Monocytes/drug effects , Mycelium/metabolism , Polysaccharides, Bacterial/isolation & purification , Polysaccharides, Bacterial/pharmacology , Anti-Inflammatory Agents/isolation & purification , Humans , Lipopolysaccharides/administration & dosage , Molecular Weight , Monocytes/immunology
19.
J Biol Chem ; 294(1): 28-37, 2019 01 04.
Article in English | MEDLINE | ID: mdl-30413532

ABSTRACT

Ischemia-related diseases are a leading cause of death worldwide, and promoting therapeutic angiogenesis is key for effective recovery from hypoxia-ischemia. Given the limited success of angiogenic factors, such as vascular endothelial growth factor, in clinical trials, it is important to find more promising angiogenic targets. Here, using both cell- and tissue-based assays and a mouse model of injury-induced ischemia, we investigated the involvement of the transient receptor potential canonical 5 (TRPC5) ion channel in angiogenesis and the effects of a TRPC5 activator, the Food and Drug Administration-approved drug riluzole, on recovery from ischemic injury. We demonstrate that TRPC5 is involved in endothelial cell sprouting, angiogenesis, and blood perfusion in an oxygen-induced retinopathy model and a hind limb ischemia model. We found a potential regulatory link between nuclear factor of activated T cell isoform c3 and angiopoietin-1 that could provide the mechanistic basis for the angiogenic function of TRPC5. Importantly, treatment with riluzole, which can activate TRPC5 in endothelial cells, improved recovery from ischemia in mice. Our study reveals TRPC5 as a potential angiogenic target and suggests riluzole as a promising drug for managing ischemic diseases.


Subject(s)
Endothelial Cells/metabolism , Ischemia/metabolism , Neovascularization, Pathologic/metabolism , Retinal Diseases/metabolism , TRPC Cation Channels/metabolism , Animals , Disease Models, Animal , Endothelial Cells/pathology , HEK293 Cells , Humans , Ischemia/genetics , Ischemia/pathology , Ischemia/physiopathology , Mice , Mice, Knockout , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , Neovascularization, Pathologic/physiopathology , Retinal Diseases/genetics , Retinal Diseases/pathology , Retinal Diseases/physiopathology , Riluzole/pharmacology , TRPC Cation Channels/antagonists & inhibitors , TRPC Cation Channels/genetics
20.
Microb Pathog ; 142: 104036, 2020 Feb 01.
Article in English | MEDLINE | ID: mdl-32017958

ABSTRACT

BACKGROUND: In the immunocompromised conditions following renal transplantation, BK virus can reactivate and cause BK virus associated nephropathy (BKVN). Increased BK viral loads and extended duration of infection have been linked to development of BKVN. The aim of this study was to observe the incidence of BKV infection and BKVN, and kinetics of infection and disease in renal transplantation recipients. METHODS: From 2014 to 2018, we conducted a longitudinal cohort observational study of 139 renal transplantation patients treated at a single clinic. Quantitative PCR assay was conducted to assess longitudinal BK viral loads. Analysis of patient clinical characteristics was performed to determine risk factors for BKV infection and associated disease. RESULTS: Of our cohort, 29 (20.9%) patients developed high BK viremia, and 7 (5.0%) developed biopsy-confirmed BKVN. Clinical parameters associated with diabetes (FBS, HbA1c) and hyperlipidemia (TG, TC, LDL-C) were found to be correlated with development of high BK viremia or BKVN. In 3 of 4 patients receiving intravenous immunoglobulin (IVIG) treatment, BK viral loads were reduced by at least 1 log within 2-3 months of administration. Significant differences were measured in BK viral loads and kidney function between BK viremic patients and BKVN patients by 3-9 months post-transplantation. CONCLUSIONS: We identified diabetes and hyperlipidemia as potential risk factors for development of high BK viremia and/or BKVN. IVIG was seen to be effective in reducing viral titers. The period 3-9 months post-transplantation was identified as important for development of BKVN from high BK viremia.

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