Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 26
Filter
1.
Heliyon ; 10(11): e32014, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38882361

ABSTRACT

N6-methyladenosine (m6A) methylation mediates cancer development by regulating cell proliferation and metastasis. This study aimed to identify whether methyltransferase 14 (METTL14) affects gastric cancer (GC) cellular functions and its underlying mechanism. METTL14 and TATA-box binding protein associated factor 10 (TAF10) levels were examined using quantitative real-time PCR, immunohistochemical assay, and Western blot. Biological functions were assessed using cell counting kit-8, colony formation, and transwell assays. The interaction between METTL14 and TAF10 was analyzed using RNA immunoprecipitation, methylated RNA immunoprecipitation, and luciferase reporter assay. A xenograft tumor mouse model was established to assess the role of METTL14 in vivo. The results suggested that METTL14 was low expressed and TAF10 was highly expressed in GC tissues and cells. METTL14 overexpression inhibited GC cell viability, colony, migration, and invasion. TAF10 was predicted and confirmed to be negatively related to METTL14. METTL14 promoted m6A methylation of TAF10 and inhibited TAF10 stability. Moreover, TAF10 counteracted the cellular behaviors regulated by METTL14. Overexpression of METTL14 inhibited tumor growth and histopathology. In conclusion, METTL14 inhibits GC progression by attenuating GC cell proliferation, migration, and invasion. Mechanistically, METTL14 promoted m6A methylation of TAF10, suppressed the stability of TAF10, and thus downregulated the TAF10 levels, These results provide a new insight into GC therapy.

2.
Front Immunol ; 15: 1384948, 2024.
Article in English | MEDLINE | ID: mdl-38779665

ABSTRACT

Lactic acid was formerly regarded as a byproduct of metabolism. However, extensive investigations into the intricacies of cancer development have revealed its significant contributions to tumor growth, migration, and invasion. Post-translational modifications involving lactate have been widely observed in histone and non-histone proteins, and these modifications play a crucial role in regulating gene expression by covalently attaching lactoyl groups to lysine residues in proteins. This discovery has greatly enhanced our comprehension of lactic acid's involvement in disease pathogenesis. In this article, we provide a comprehensive review of the intricate relationship between lactate and tumor immunity, the occurrence of lactylation in malignant tumors, and the exploitation of targeted lactate-lactylation in tumor immunotherapy. Additionally, we discuss future research directions, aiming to offer novel insights that could inform the investigation, diagnosis, and treatment of related diseases.


Subject(s)
Immunotherapy , Lactic Acid , Neoplasms , Protein Processing, Post-Translational , Humans , Neoplasms/therapy , Neoplasms/immunology , Neoplasms/metabolism , Immunotherapy/methods , Lactic Acid/metabolism , Animals
3.
J Inflamm Res ; 17: 3031-3041, 2024.
Article in English | MEDLINE | ID: mdl-38770174

ABSTRACT

The maintenance of normal vascular function and homeostasis is largely dependent on the signaling mechanisms that occur within and between cells of the vasculature. TGF-ß-activated kinase 1 (TAK1), a multifaceted signaling molecule, has been shown to play critical roles in various tissue types. Although the precise function of TAK1 in the vasculature remains largely unknown, emerging evidence suggests its potential involvement in both physiological and pathological processes. A comprehensive search strategy was employed to identify relevant studies, PubMed, Web of Science, and other relevant databases were systematically searched using keywords related to TAK1, TABs and MAP3K7.In this review, we discussed the role of TAK1 in vascular signaling, with a focus on its function, activation, and related signaling pathways. Specifically, we highlight the TA1-TABs complex is a key factor, regulating vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) involved in the processes of inflammation, vascular proliferation and angiogenesis. This mini review aims to elucidate the evidence supporting TAK1 signaling in the vasculature, in order to better comprehend its beneficial and potential harmful effects upon TAK1 activation in vascular tissue.

4.
Front Oncol ; 13: 1104888, 2023.
Article in English | MEDLINE | ID: mdl-37188194

ABSTRACT

Immune-related adverse events (irAEs), including skin injury, liver and kidney injury, colitis, as well as cardiovascular adverse events, are a series of complications arising during the treatment of immune checkpoint inhibitors (ICIs). Cardiovascular events are the most urgent and the most critical, as they can end life in a short period of time. With the widespread use of ICIs, the number of immune-related cardiovascular adverse events (irACEs) induced by ICIs has increased. More attention has been paid to irACEs, especially regarding cardiotoxicity, the pathogenic mechanism, diagnosis and treatment. This review aims to assess the risk factors for irACEs, to raise awareness and help with the risk assessment of irACEs at an early stage.

5.
Aging Dis ; 14(1): 6-8, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36818561
6.
Diabetol Metab Syndr ; 13(1): 49, 2021 Apr 28.
Article in English | MEDLINE | ID: mdl-33910639

ABSTRACT

BACKGROUND: As a subcomponent of low-density lipoprotein cholesterol (LDL-C), small dense LDL-C (sdLDL-C) has been suggested to be a better predictor of cardiovascular diseases (CVD). The aim of this research was to evaluate the predictive value of the sdLDL-C in cardiovascular events (CVs) in Chinese elderly patients with type 2 diabetes mellitus (DM). METHODS: A total of 386 consecutive type 2 DM patients were included into this study during December 2014 to December 2016. The serum sdLDL-C level of each subject was measured by homogeneous method. During a period of 48-month's follow-up, the occurrence of CVs and associated clinical information were recorded. Receiver operating characteristic (ROC) curves were used to assess the predictive value of serum sdLDL-C to occurrence of major CVs. RESULTS: A total of 92 CVs occurred during the study period. The ROC curve analysis manifested that sdLDL-C in the study population had a matchable discriminatory power (AUC for sdLDL-C was 0.7366, P = 0.003). In addition, Kaplan-Meier event-free survival curves displayed an obvious increase of CVs risk for sdLDL-C ≧ 26 mg/dL (log-rank = 9.10, P = 0.003). This phenomenon had analogous results in patients who received statins at baseline (log rank = 7.336, P = 0.007). Cox regression analysis revealed that the increase in HbA1c, glucose, LDL-C, sdLDL-C, non-high-density lipoprotein cholesterol (non-HDL-C) and apolipoprotein B (ApoB) and the decrease in apolipoprotein AI (ApoAI) were obviously interrelated with heightened CVs risk. Multiple Cox regression demonstrated that the increase of sdLDL-C and hemoglobin A1c (HbA1c) was significantly correlated with CVs. The results of the study indicated that high sdLDL-C level (> 10 mg/dL) was a risk factor for CVs in the multivariate model (HR 1.281, 95% CI 1.225-16.032; P < 0.01). CONCLUSION: sdLDL-C level could be an effective predictor in predicting the future CVs for Chinese elderly patients with type 2 DM and dyslipidemia.

7.
Lipids Health Dis ; 17(1): 84, 2018 Apr 17.
Article in English | MEDLINE | ID: mdl-29665812

ABSTRACT

BACKGROUND: Long-term persistence of statin therapy provided an ongoing reduction in mortality among patients with and without a known history of CVD, and renoprotective effect on CKD patients. Until now, very few reports are available from China to address the effects of statin therapy in CKD + CAD patients. METHODS: We compared the effects of long-term statin therapy (follow-up time 4 years) in terms of cardiovascular events, all-cause death, and cardiac death among 254 CKD patients with or without CAD. RESULTS: Long-term statin therapy was much more effective in the CKD + CAD patients compared with CKD patients. In the CAD + CKD patients, long-term statins showed a 22.2% reduction in the CVs rate (P = 0.012). With regard to the all-cause and cardiac deaths, long-term statins had significant treatment effects on the CAD + CKD patients (reduction of about 28.1% in mortality rates, P < 0.001). In contrast, long-term statin therapy exerted no significant influence on the clinical outcomes of the CKD-only patients. CONCLUSION: Long-term statin therapy more dramatically reduced the CVs and mortality rates of the CKD patients with concomitant CAD. In contrast, CKD-only patients had a good prognosis and did not appear to require statin treatment.


Subject(s)
Coronary Artery Disease/complications , Coronary Artery Disease/drug therapy , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Renal Insufficiency, Chronic/complications , Renal Insufficiency, Chronic/drug therapy , Female , Humans , Kaplan-Meier Estimate , Male , Proportional Hazards Models , Treatment Outcome
8.
BMC Infect Dis ; 17(1): 226, 2017 03 23.
Article in English | MEDLINE | ID: mdl-28335818

ABSTRACT

BACKGROUND: There is limited data on the genotype distribution of human papillomavirus (HPV) in the Taihu River Basin, home to 1.29 million people on the coast of eastern China. This study evaluated the prevalence and genotypes among different female age groups in this region. METHODS: Twenty-six HPV strains (low-risk HPV 6, 11, 40, 42, 44, 61, 73 and high-risk HPV 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 55, 56, 58, 59, 66, 68, 82, and 83) were detected using Tellgenplex™ HPV technology in samples obtained from three clinical hospitals located in different regions of the Taihu Lake Basin. RESULTS: The results showed that 1855 samples (20.97% of all samples) were found to be HPV-positive. Of these, 1375 samples (15.55% of all samples) were found to have a single HPV infection. Age-specific prevalence showed two peaks, one that corresponded to the group of 21-30 year-old women and the other peak that corresponded to the group of women over 51 years old. The three most prevalent genotypes were HPV52 (19.95%, 370/1855), HPV16 (13.48%, 150/1855), and HPV58 (11.32%, 210/1855). Mixed strains HPV58 + HPV33 and HPV58 + HPV52 were most commonly found in females infected with multiple HPV types. CONCLUSIONS: This investigation reveals that HPV infection in the Taihu River Basin varied significantly among different age groups. The most prevalent genotypes are included in the nonavalent vaccine, V503, however this vaccine is not licensed for use in mainland China. The most frequently occurring genotypes should be considered in the development of next-generation HPV vaccines for optimal protection of public health.


Subject(s)
DNA, Viral/analysis , Genotype , Papillomaviridae/genetics , Papillomavirus Infections/virology , Adult , Aged , China/epidemiology , Female , Humans , Middle Aged , Papillomaviridae/isolation & purification , Papillomavirus Infections/diagnosis , Papillomavirus Infections/epidemiology , Papillomavirus Vaccines , Prevalence , Risk , Rivers , Young Adult
9.
BMC Nephrol ; 17(1): 143, 2016 10 06.
Article in English | MEDLINE | ID: mdl-27716087

ABSTRACT

BACKGROUND: Cardiovascular disease (CVD) is often comorbid with chronic kidney disease (CKD). Small low-density lipoprotein cholesterol (sdLDL-C) has also been found to increase risk for CVD. The goal of the present study was to determine the nature of the relationship between sdLDL-C concentration and CVD in patients with CKD. METHODS: One-hundred and forty-five subjects (113 men and 32 women) with CKD (Stage 3 and Stage 4) participated this retrospective study. The concentration of sdLDL-C was measured in samples from 145 CKD patients between 2010 and 2012 during a four-year follow-up period. RESULTS: A total of eight fatal cardiovascular events (CVs) and 46 nonfatal CVs were registered in the four-year follow-up period. Multivariate Cox regression analysis showed that sdLDL-C [1.278, 95 % (1.019-1.598)] and sdLDL-C/LDL-C [2.456, 95 % (1.421-15.784)], at final observation, were independent risks of CVs. A Kaplan-Meier survival analysis showed that patients with sdLDL-C >38 mg/dl (logrank: 4.375, P = 0.037), and sdLDL-C/LDL-C ratio >0.3 levels (logrank: 11.94, P = 0.018) were at increased risk for CVs. CONCLUSION: The results of this study indicated that for patients suffering CKD, a significant relationship exists between an elevated sdLDL-C concentration and the risk of cardiovascular disease.


Subject(s)
Cardiovascular Diseases/epidemiology , Cholesterol, LDL/blood , Renal Insufficiency, Chronic/blood , Renal Insufficiency, Chronic/epidemiology , Aged , Comorbidity , Diabetes Mellitus/epidemiology , Female , Follow-Up Studies , Humans , Hypertension/epidemiology , Kaplan-Meier Estimate , Male , Middle Aged , Prevalence , Proportional Hazards Models , Retrospective Studies , Risk Factors
10.
Gastroenterol Res Pract ; 2016: 5120760, 2016.
Article in English | MEDLINE | ID: mdl-28101103

ABSTRACT

Background. Currently there is no indicator that can evaluate actual liver lesion for early stages of viral hepatitis, nonalcoholic fatty liver disease (NAFLD), and cirrhosis. Aim of this study was to investigate if albumin binding function could better reflect liver function in these liver diseases. Methods. An observational study was performed on 193 patients with early NAFLD, viral hepatitis, and cirrhosis. Cirrhosis patients were separated according to Child-Pugh score into A, B, and C subgroup. Albumin metal ion binding capacity (Ischemia-modified albumin transformed, IMAT) and fatty acid binding capacity (total binding sites, TBS) were detected. Results. Both IMAT and TBS were significantly decreased in patients with NAFLD and early hepatitis. In hepatitis group, they declined prior to changes of liver enzymes. IMAT was significantly higher in cirrhosis Child-Pugh class A group than hepatitis patients and decreased in Child-Pugh class B and class C patients. Both IMAT/albumin and TBS/albumin decreased significantly in hepatitis and NAFLD group patients. Conclusions. This is the first study to discover changes of albumin metal ion and fatty acid binding capacities prior to conventional biomarkers for liver damage in early stage of liver diseases. They may become potential earliest sensitive indicators for liver function evaluation.

11.
Lipids Health Dis ; 14: 137, 2015 Oct 29.
Article in English | MEDLINE | ID: mdl-26510458

ABSTRACT

BACKGROUND: Small dense low-density lipoprotein cholesterol (sdLDL-C) concentration was useful in the assessment of the presence of cardiovascular diseases (CVD) and its severity. We examined whether SdLDL-C is more closely associated with carotid artery intima-media thickness (CA-IMT), a surrogate measure of atherosclerosis, than LDL-C and traditional CVD risk factors in Chinese healthy subjects. METHODS: We measured CA-IMT, blood pressure (BP), sdLDL-C, glucose metabolism and lipid in 183 native Chinese healthy subjects. CA-IMT was assessed by ultrasonography, and sdLDL-C concentrations were measured by a homogenous assay. Pearson's correlation coefficient analyses and Multiple regression analyses were used to examine the relationships between CA-IMT values and other clinical variables. RESULTS: The sdLDL-C level was significantly higher in males than in females (p <0.05) and there was an age effect on sdLDL-C (p <0.05). When the effects of age, gender and other traditional CVD risk factors were adjusted using multiple regression analysis. CA-IMT remained significantly associated with sdLDL-C(ß = 0.437, p <0.001). CONCLUSIONS: There are gender and age differences in sdLDL-C levels among a healthy Chinese population. Moreover, we found adjusted traditional CVD risk factors such as higher age, male sex, and other traditional CVD risk factors, the association between CA-IMT and SdLDL-C remained significant. sdLDL-C is may be a useful predictor in the assessment of CA-IMT in Chinese population.


Subject(s)
Carotid Arteries/anatomy & histology , Carotid Intima-Media Thickness , Cholesterol, LDL/blood , Adult , Age Factors , Asian People , Biomarkers/blood , Blood Glucose/metabolism , Blood Pressure/physiology , Body Mass Index , Carotid Arteries/diagnostic imaging , Female , Humans , Male , Middle Aged , Regression Analysis , Risk Assessment , Risk Factors , Sex Factors
12.
Target Oncol ; 9(3): 263-72, 2014 Sep.
Article in English | MEDLINE | ID: mdl-23943313

ABSTRACT

Sperm protein 17 (Sp17) is selectively overexpressed in several human malignancies including ovarian carcinoma, but is absent or expressed at low levels in most normal tissues. Previous work from our group characterized an anti-Sp17 monoclonal antibody (clone 3C12) and showed that it specifically targeted tumor cells. In this report, we investigated whether a novel immunoconjugate containing 3C12 linked to the chemotherapeutic agent doxorubicin [(DOX) Adriamycin] had antitumor activity against ovarian cancer cell lines and tumor models. DOX was conjugated to 3C12 using a linker, and the specificity of 3C12-DOX was examined in Sp17-positive SKOV3 and Sp17-negative COC2 ovarian cancer cells using cell-based ELISA and internalization assays. The cytotoxicity of 3C12-DOX was assessed with the MTT assay, and its therapeutic effectiveness was evaluated in immunodeficient mice bearing SKOV3 cells. In vitro, the 3C12-DOX immunoconjugate specifically bound to and was internalized by Sp17-positive SKOV3 cells but did not bind to Sp17-negative cells. Treatment with 3C12-DOX (0.001 to 10 µg/mL) decreased the viability of SKOV3 cells in a Sp17-specific manner. In vivo, 3C12-DOX (3 mg/kg) induced the regression of established SKOV3 xenograft tumors in BALB/c mice compared with control treatment. The antitumor effects of 3C12-DOX were significantly associated with the induction of apoptosis in tumor cells. In addition, 3C12-DOX showed no observable adverse effects or toxicity when compared with DOX alone in mice bearing ovarian tumor xenografts. Our findings suggest that 3C12-DOX may be a potential antibody-drug conjugate for clinical development.


Subject(s)
Antibodies, Monoclonal/pharmacology , Antigens, Surface/immunology , Carrier Proteins/immunology , Doxorubicin/pharmacology , Immunoconjugates/pharmacology , Ovarian Neoplasms/drug therapy , Animals , Antibiotics, Antineoplastic/administration & dosage , Antibodies, Monoclonal/immunology , Calmodulin-Binding Proteins , Cell Line, Tumor , Female , Humans , Membrane Proteins , Mice , Mice, Inbred BALB C , Mice, Nude , Molecular Targeted Therapy , Ovarian Neoplasms/immunology , Random Allocation , Xenograft Model Antitumor Assays
13.
BMC Infect Dis ; 13: 253, 2013 May 31.
Article in English | MEDLINE | ID: mdl-23725337

ABSTRACT

BACKGROUND: The yeast Candida is one of the most frequent pathogens isolated from bloodstream infections and is associated with significant morbidity and mortality. Problems with clinical and microbiological diagnosis of invasive candidiasis (IC) have prompted the development of non-culture-based laboratory methods. Previous reports suggest that serological detection of antibodies might be useful for diagnosing systemic candidiasis. METHODS: Diagnosis of IC using antibodies against recombinant Candida albicans enolase (Eno) and fructose-bisphosphate aldolase (Fba1) was evaluated. Using recombinant Eno and Fba1 as coating antigens, enzyme-linked immunosorbent assays (ELISAs) were used to analyze sera from patients with candidemia (n = 101), Candida colonization (n = 50), bacteremia (n = 84), invasive aspergillosis (n = 40); and from healthy controls (n = 200). RESULTS: The results demonstrated that ELISA detection of anti-Eno and anti-Fba1 IgG distinguished IC from other pathogenic infections in patients and healthy individuals. The sensitivity, specificity, and positive and negative predictive values were 72.3%, 94.7%, 78.5% and 93% for anti-Eno, and 87.1%, 92.8%, 76.5% and 96.4% for anti-Fba1 antibodies, respectively. Combining these two tests improved sensitivity up to 90.1% and negative predictive value up to 97.1%, with specificity and positive predictive values of 90.6% and 72.2%. The tests were specific to the Candida genus and antibody titers were higher for candidemia patients than for controls. Positive antibody tests were obtained before blood culture results for 42.2% of patients for anti-Eno and 51.1% for anti-Fba1. CONCLUSION: These data suggest that tests that detect IgG antibodies against Candida enolase and fructose-bisphosphate aldolase, especially when used in combination, could be a powerful tool for diagnosing IC.


Subject(s)
Antibodies, Fungal/blood , Candida/immunology , Candidemia/diagnosis , Fructose-Bisphosphate Aldolase/immunology , Fungal Proteins/immunology , Immunoglobulin G/blood , Phosphopyruvate Hydratase/immunology , Adult , Aged , Aged, 80 and over , Antigens, Fungal/immunology , Candida/enzymology , Candida/isolation & purification , Candidemia/immunology , Case-Control Studies , Cohort Studies , Enzyme-Linked Immunosorbent Assay/methods , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Serologic Tests/methods , Statistics, Nonparametric
15.
Clin Chim Acta ; 413(9-10): 938-43, 2012 May 18.
Article in English | MEDLINE | ID: mdl-22366166

ABSTRACT

BACKGROUND: Invasive aspergillosis (IA) is an important cause of mortality in critically ill patients, but the diagnosis is difficult as clinical and radiological signs are neither sensitive nor specific. Serum galactomannan (GM) is a useful marker for IA, but exhibits low sensitivity in non-neutropenic patients. In our previous work, strong antibody reactivity to thioredoxin reductase of Aspergillus fumigatus was found in non-neutropenic IA patients. METHODS AND RESULTS: Using recombinant thioredoxin reductase GliT (TR), an antigenic protein secreted by A. fumigatus, as the coating antigen, an enzyme-linked immunosorbent assay (ELISA) for detecting anti-TR antibodies was developed. The antibody response to TR in IA animal models and 42 non-neutropenic patients with culture- and/or histology-documented IA was investigated. The results showed that anti-TR antibody was detectable in rabbit serum 7-9 days after exposure to the fungus. The sensitivity and specificity of the anti-TR antibody assay in patients were 80.9% and 96%, respectively, while the sensitivity of GM in this group of patients was only 52.3%. The specificity of the assay was confirmed by testing the sera from patients infected with other pathogenic fungal species and bacteria.


Subject(s)
Antibodies, Fungal/blood , Antibody Specificity , Aspergillosis/blood , Neutropenia , Thioredoxin-Disulfide Reductase/blood , Adult , Aged , Aged, 80 and over , Animals , Aspergillosis/diagnosis , Biomarkers/blood , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/standards , Female , Galactose/analogs & derivatives , Humans , Male , Mannans/blood , Middle Aged , Rabbits , Sensitivity and Specificity , Serologic Tests/methods , Serologic Tests/standards
16.
BMC Microbiol ; 12: 11, 2012 Jan 18.
Article in English | MEDLINE | ID: mdl-22251604

ABSTRACT

BACKGROUND: There has been a rising incidence of invasive aspergillosis (IA) in critically ill patients, even in the absence of an apparent predisposing immunodeficiency. The diagnosis of IA is difficult because clinical signs are not sensitive and specific, and serum galactomannan has relatively low sensitivity in this group of patients. Therefore, more prompt and accurate disease markers for early diagnosis are needed. To establish disease markers demands a thorough knowledge of fungal antigens which may be detected in the serum or other body fluids of patients. Herein we report novel immunodominant antigens identified from extracellular proteins of Aspergillus fumigatus. RESULTS: Extracellular proteins of A. fumigatus were separated by two-dimensional electrophoresis (2-DE) and probed with the sera from critically ill patients with proven IA. The immunoreactive protein spots were identified by MALDI-TOF mass spectrometry (MALDI-TOF -MS). Forty spots from 2DE gels were detected and 17 different proteins were identified as immunogenic in humans. Function annotation revealed that most of these proteins were metabolic enzymes involved in carbohydrate, fatty acid, amino acid, and energy metabolism. One of the proteins, thioredoxin reductase GliT (TR), which showed the best immunoactivity, was analyzed further for secretory signals, protein localization, and homology. The results indicated that TR is a secretory protein with a signal sequence exhibiting a high probability for secretion. Furthermore, TR did not match any human proteins, and had low homology with most other fungi. The recombinant TR was recognized by the sera of all proven IA patients with different underlying diseases in this study. CONCLUSIONS: The immunoreactive proteins identified in this study may be helpful for the diagnosis of IA in critically ill patients. Our results indicate that TR and other immunodominant antigens have potential as biomarkers for the serologic diagnosis of invasive aspergillosis.


Subject(s)
Antibodies, Fungal/blood , Antigens, Fungal/immunology , Aspergillosis/diagnosis , Aspergillus fumigatus/isolation & purification , Oxidoreductases/immunology , Adult , Aged , Aspergillosis/immunology , Aspergillus fumigatus/immunology , Biomarkers/blood , Blotting, Western , Electrophoresis, Gel, Two-Dimensional , Female , Humans , Immunoassay/methods , Male , Middle Aged , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
17.
J Environ Sci (China) ; 24(6): 1099-105, 2012.
Article in English | MEDLINE | ID: mdl-23505878

ABSTRACT

The toxicity of chlortetracycline (CTC) on maize (Zea mays L.) growth and reactive oxygen species (ROS) generation was studied. The root and shoot lengths and fresh weights of maize seedlings were inhibited by CTC treatment (p < 0.05). Root length was more sensitive than other parameters with the EC10 value of 0.064 mg/L. The spin trapping technique followed by electron paramagnetic resonance (EPR) analysis was used to quantify the ROS production. The ROS generated in maize roots after exposure to CTC was identified as hydroxyl radical (*OH). The EPR signal intensity correlated positively with the logarithm of CTC concentrations exposed (p < 0.05). The dynamic changes of malondialdehyde (MDA) contents and the antioxidative enzyme activities in maize roots were also determined. As compared to the control group, CTC was found to significantly increase MDA content. Treatment of maize roots with the *OH scavenger sodium benzoate (SB) reduced the MDA content and enhanced the antioxidative enzyme activities. The results demonstrated the harmfulness of CTC at high dose to maize in the early developmental stage, and clarified that the inducement of *OH is one of the mechanisms of CTC toxicity.


Subject(s)
Anti-Bacterial Agents/toxicity , Chlortetracycline/toxicity , Reactive Oxygen Species/metabolism , Zea mays/drug effects , Catalase/metabolism , Malondialdehyde/metabolism , Peroxidase/metabolism , Plant Roots/drug effects , Plant Roots/growth & development , Plant Roots/metabolism , Plant Shoots/drug effects , Plant Shoots/growth & development , Plant Shoots/metabolism , Superoxide Dismutase/metabolism , Zea mays/growth & development , Zea mays/metabolism
18.
Am J Chin Med ; 37(6): 1167-77, 2009.
Article in English | MEDLINE | ID: mdl-19938224

ABSTRACT

To study the oxidative stress level of the influenza virus A FM1 subset-infected mouse in intranasal inhalation as a model, we employ an ascorbyl radical's ESR (electron spin resonance) spectrum as an oxidative stress biomarker. These infected mice were pretreated with Ribavirin, ascorbic acid, superoxide dismutase (SOD) or Kegan Liyan oral prescription (KGLY, proprietary Chinese medicine for influenza and common cold) in the stomach tube for 3 days, and then followed by the virus-infecting for 4 days. On the 4th day, samples were collected. It is recognized the strength of ascorbyl radical's ESR signal (A(-.)) (a(H4 = 0.177) Gauss, g = 2.00517) denotes oxidative stress level in vivo and in vitro. The magnitude of ESR spectrum (28.65 +/- 10.71 AU) in mice infected with influenza virus was significantly higher than those of healthy control mice (19.10 +/- 3.61 AU). Serum A(-.) in mice treated with Ribavirin, ascorbic acid, SOD and KGLY declined to 19.70 +/- 6.05, 18.50 +/- 2.93 and 16.25 +/- 3.59, 18.40 +/- 2.14 AU respectively. It is close to A(-.) signal height in healthy controls via down-regulation of the influenza virus-caused oxidative stress level getting decline in the lung index of pneumonia as compare to those of untreated healthy and the influenza virus infected mice pneumonia. It is well known that SOD can prevent the influenza virus pneumonia enhancing mouse survival rate; Ribavirin can treat viral diseases. Data from this study suggested that KGLY may indirectly relieve influenza virus-infected pneumonia via down- regulation of virus caused oxidative stress coupled with a redox reaction cascade as ribavirin, ascorbic acid and SOD.


Subject(s)
Antioxidants/therapeutic use , Antiviral Agents/therapeutic use , Ascorbic Acid/metabolism , Drugs, Chinese Herbal/therapeutic use , Influenza A virus/drug effects , Orthomyxoviridae Infections/drug therapy , Oxidative Stress/drug effects , Animals , Antioxidants/pharmacology , Antiviral Agents/pharmacology , Biomarkers , Down-Regulation , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/pharmacology , Electron Spin Resonance Spectroscopy , Female , Free Radicals/metabolism , Lung/drug effects , Magnoliopsida , Male , Mice , Mice, Inbred Strains , Oxidation-Reduction , Phytotherapy , Pneumonia, Viral/drug therapy , Pneumonia, Viral/metabolism , Ribavirin/pharmacology , Ribavirin/therapeutic use , Superoxide Dismutase/pharmacology , Superoxide Dismutase/therapeutic use
19.
Biochemistry ; 46(41): 11451-8, 2007 Oct 16.
Article in English | MEDLINE | ID: mdl-17892301

ABSTRACT

S-Adenosylhomocysteine hydrolase (SAHH) regulates biomethylation and homocysteine metabolism and thus is an attractive target in drug design studies. SAHH has been shown to be a copper binding protein in vivo; however, the structure and catalytic mechanism of SAHH exclude a role for Cu2+. In the present work, we studied the mechanism of inhibition of SAHH activity by Cu2+. The experimental results showed that Cu2+ inhibited SAHH activity in a noncompetitive manner. Binding of Cu2+ to SAHH resulted in the release of NAD+ cofactors, explaining the loss of the enzymatic activity of SAHH. Further investigation by an ESR probe and computational simulation suggested that Cu2+ could bind at the central channel and interrupt the subunit interactions of SAHH, resulting in a large decrease in affinity to the NAD+ cofactor. This effect of Cu2+ resembled that of enzyme mutations at the C-terminal domain or Asp244 [Komoto, J., Huang, Y., Gomi, T., Ogawa, H., Takata, Y., Fujioka, M., and Takusagawa, F. (2000) Effects of site-directed mutagenesis on structure and function of recombinant rat liver S-adenosylhomocysteine hydrolase. Crystal structure of D244E mutant enzyme, J. Biol. Chem. 275, 32147-32156]. The mechanism of action of Cu2+ on SAHH suggested a possible regulative role for Cu2+ on the intracellular activity of SAHH. This could be helpful in understanding the biological effects of copper compounds and suggest a potential coupling mechanism between biomethylation and the redox states of cells.


Subject(s)
Adenosylhomocysteinase/antagonists & inhibitors , Adenosylhomocysteinase/chemistry , Copper/pharmacology , NAD/metabolism , Apoenzymes/chemistry , Apoenzymes/metabolism , Drug Design , Female , Humans , Kinetics , Microwaves , Placenta/enzymology , Pregnancy , Protein Binding , Recombinant Proteins/antagonists & inhibitors , Recombinant Proteins/chemistry
20.
J Inorg Biochem ; 100(7): 1280-9, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16678267

ABSTRACT

Oral administration of lanthanum chloride (LaCl(3)) was reported to inhibit atherosclerosis in experimental animals, but the mechanism was not clear. In the present work, the effects of La(III) and other lanthanide ions (Ln(III)) on Cu(II)-induced oxidation of isolated low-density lipoprotein (LDL) and the related mechanism were investigated. By monitoring the formation of conjugated dienes (CD), low concentrations of La(III), Gd(III) and Y(III) were found to inhibit Cu(II)-induced LDL oxidation kinetically, as characterized by the prolongation of the lag time, the decrease of the maximal accumulation of CD, and the maximal rate of CD accumulation. Using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) and alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN) as spin trapping agents, the electron spin resonance (ESR) results showed that La(III) and Gd(III) at low concentrations significantly decreased the level of free radicals, including alkoxyl radical (LO*), alkyl radical (L*), and a transient radical, alkylperoxyl radical (LOO*), generated during LDL oxidation induced by Cu(II). In addition, Fourier-transform infrared spectroscopy (FT-IR) study revealed that La(III) might cause the conformational change and the less aggregation of apolipoprotein B-100 (apoB) in LDL, as demonstrated by the decreasing contents of alpha-helix, intermolecular beta-sheet, unordered structure and beta-turns, and the increasing contents of intramolecular beta-sheet and beta-strands. The inhibitory effect of Ln(III) on Cu(II)-induced LDL oxidation was discussed on the basis of the decreased free radical level and the second structural changes of apoB in LDL.


Subject(s)
Copper/chemistry , Lanthanoid Series Elements/chemistry , Lipoproteins, LDL/blood , Apolipoprotein B-100 , Apolipoproteins B/blood , Humans , Kinetics , Oxidation-Reduction , Spectroscopy, Fourier Transform Infrared
SELECTION OF CITATIONS
SEARCH DETAIL
...