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1.
J Biol Chem ; 299(2): 102845, 2023 02.
Article in English | MEDLINE | ID: mdl-36586435

ABSTRACT

Obesity and diabetes normally cause mitochondrial dysfunction and hepatic lipid accumulation, while fatty acid synthesis is suppressed and malonyl-CoA is depleted in the liver of severe obese or diabetic animals. Therefore, a negative regulatory mechanism might work for the control of mitochondrial fatty acid metabolism that is independent of malonyl-CoA in the diabetic animals. As mitochondrial ß-oxidation is controlled by the acetyl-CoA/CoA ratio, and the acetyl-CoA generated in peroxisomal ß-oxidation could be transported into mitochondria via carnitine shuttles, we hypothesize that peroxisomal ß-oxidation might play a role in regulating mitochondrial fatty acid oxidation and inducing hepatic steatosis under the condition of obesity or diabetes. This study reveals a novel mechanism by which peroxisomal ß-oxidation controls mitochondrial fatty acid oxidation in diabetic animals. We determined that excessive oxidation of fatty acids by peroxisomes generates considerable acetyl-carnitine in the liver of diabetic mice, which significantly elevates the mitochondrial acetyl-CoA/CoA ratio and causes feedback suppression of mitochondrial ß-oxidation. Additionally, we found that specific suppression of peroxisomal ß-oxidation enhances mitochondrial fatty acid oxidation by reducing acetyl-carnitine formation in the liver of obese mice. In conclusion, we suggest that induction of peroxisomal fatty acid oxidation serves as a mechanism for diabetes-induced hepatic lipid accumulation. Targeting peroxisomal ß-oxidation might be a promising pathway in improving hepatic steatosis and insulin resistance as induced by obesity or diabetes.


Subject(s)
Diabetes Mellitus, Experimental , Fatty Liver , Insulin Resistance , Animals , Mice , Acetyl Coenzyme A/metabolism , Diabetes Mellitus, Experimental/metabolism , Fatty Acids/metabolism , Fatty Liver/metabolism , Liver/metabolism , Malonyl Coenzyme A/metabolism , Mice, Obese , Obesity/metabolism , Oxidation-Reduction , Acetylcarnitine/metabolism
2.
J Biol Chem ; 299(9): 105174, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37599002

ABSTRACT

Recent studies provide evidence that peroxisomal ß-oxidation negatively regulates mitochondrial fatty acid oxidation, and induction of peroxisomal ß-oxidation causes hepatic lipid accumulation. However, whether there exists a triggering mechanism inducing peroxisomal ß-oxidation is not clear. Long-chain dicarboxylic acids (LCDAs) are the product of mono fatty acids subjected to ω-oxidation, and both fatty acid ω-oxidation and peroxisomal ß-oxidation are induced under ketogenic conditions, indicating there might be a crosstalk between. Here, we revealed that administration of LCDAs strongly induces peroxisomal fatty acid ß-oxidation and causes hepatic steatosis in mice through the metabolites acetyl-CoA and hydrogen peroxide. Under ketogenic conditions, upregulation of fatty acid ω-oxidation resulted in increased generation of LCDAs and induction of peroxisomal ß-oxidation, which causes hepatic accumulation of lipid droplets in animals. Inhibition of fatty acid ω-oxidation reduced LCDA formation and significantly lowered peroxisomal ß-oxidation and improved hepatic steatosis. Our results suggest that endogenous LCDAs act as triggering molecules inducing peroxisomal ß-oxidation and hepatic triacylglycerol deposition. Targeting fatty acid ω-oxidation might be an effective pathway in treating fatty liver and related metabolic diseases through regulating peroxisomal ß-oxidation.

3.
Appetite ; 199: 107406, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38735308

ABSTRACT

OBJECTIVE: This study aims to 1) explore the association between autistic traits and eating behaviors in Chinese preschoolers; 2) explore the mediating role of sensory processing patterns on the relation of autistic traits and eating-related behaviors; and 3) examine home nurturing environment as a moderator between autistic traits and eating-related behaviors. We hypothesize that there is a significant association between autistic traits and eating behaviors, which is mediated by sensory processing patterns and moderated by the home nurturing environment. METHOD: 509 children aged 3-4 years participated in this cross-sectional research. They were assessed using the Social Responsiveness Scale-Second Edition (SRS-2) for autistic traits, the Chinese Preschoolers' Eating Behavior Questionnaire (CPEBQ) for eating-related behaviors, the Short Sensory Profile-Second Edition (SSP-2) for sensory processing patterns, and the Children Home Nurture Environment Questionnaire (CHNEQ) for home nurturing environment. Mediation regression analyses were used to examine the role of sensory processing patterns, while moderation analyses to examine the role of home nurturing environment. RESULTS: We observed a positive association between autistic traits and eating behavior problems among typically developed children. Sensory processing patterns significantly mediated the impact of autistic traits on children's eating-related behaviors and home nurturing environment also moderated this relationship. DISCUSSION: Our research suggests that Chinese preschoolers with higher autistic traits may face more eating challenges when they possess more heightened sensory processing patterns, while living in supportive home environments helps to improve their eating behaviors. These findings contribute to the understanding of how and to what extent eating problems are influenced by autistic traits, and they offer insight into the alleviation of eating problems from the perspectives of sensory patterns and family nurturing environments.


Subject(s)
Feeding Behavior , Home Environment , Humans , Child, Preschool , Male , Female , Feeding Behavior/psychology , Cross-Sectional Studies , Surveys and Questionnaires , China , Autistic Disorder/psychology , Child Behavior/psychology , Sensation , Asian People/psychology , East Asian People
4.
J Biol Chem ; 298(3): 101660, 2022 03.
Article in English | MEDLINE | ID: mdl-35124006

ABSTRACT

Diabetes normally causes lipid accumulation and oxidative stress in the kidneys, which plays a critical role in the onset of diabetic nephropathy; however, the mechanism by which dysregulated fatty acid metabolism increases lipid and reactive oxygen species (ROS) formation in the diabetic kidney is not clear. As succinate is remarkably increased in the diabetic kidney, and accumulation of succinate suppresses mitochondrial fatty acid oxidation and increases ROS formation, we hypothesized that succinate might play a role in inducing lipid and ROS accumulation in the diabetic kidney. Here we demonstrate a novel mechanism by which diabetes induces lipid and ROS accumulation in the kidney of diabetic animals. We show that enhanced oxidation of dicarboxylic acids by peroxisomes leads to lipid and ROS accumulation in the kidney of diabetic mice via the metabolite succinate. Furthermore, specific suppression of peroxisomal ß-oxidation improved diabetes-induced nephropathy by reducing succinate generation and attenuating lipid and ROS accumulation in the kidneys of the diabetic mice. We suggest that peroxisome-generated succinate acts as a pathological molecule inducing lipid and ROS accumulation in kidney, and that specifically targeting peroxisomal ß-oxidation might be an effective strategy in treating diabetic nephropathy and related metabolic disorders.


Subject(s)
Diabetes Mellitus, Experimental , Diabetic Nephropathies , Kidney , Peroxisomes , Succinic Acid , Animals , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Diabetic Nephropathies/metabolism , Diabetic Nephropathies/pathology , Fatty Acids/metabolism , Female , Humans , Kidney/metabolism , Lipid Metabolism , Male , Mice , Oxidative Stress , Peroxisomes/metabolism , Reactive Oxygen Species/metabolism , Succinic Acid/metabolism
5.
J Biol Chem ; 298(2): 101572, 2022 02.
Article in English | MEDLINE | ID: mdl-35007532

ABSTRACT

Although diabetes normally causes an elevation of cholesterol biosynthesis and induces hypercholesterolemia in animals and human, the mechanism linking diabetes to the dysregulation of cholesterol biosynthesis in the liver is not fully understood. As liver peroxisomal ß-oxidation is induced in the diabetic state and peroxisomal oxidation of fatty acids generates free acetate, we hypothesized that peroxisomal ß-oxidation might play a role in liver cholesterol biosynthesis in diabetes. Here, we used erucic acid, a specific substrate for peroxisomal ß-oxidation, and 10,12-tricosadiynoic acid, a specific inhibitor for peroxisomal ß-oxidation, to specifically induce and suppress peroxisomal ß-oxidation. Our results suggested that induction of peroxisomal ß-oxidation increased liver cholesterol biosynthesis in streptozotocin-induced diabetic mice. We found that excessive oxidation of fatty acids by peroxisomes generated considerable free acetate in the liver, which was used as a precursor for cholesterol biosynthesis. In addition, we show that specific inhibition of peroxisomal ß-oxidation decreased cholesterol biosynthesis by reducing acetate formation in the liver in diabetic mice, demonstrating a crosstalk between peroxisomal ß-oxidation and cholesterol biosynthesis. Based on these results, we propose that induction of peroxisomal ß-oxidation serves as a mechanism for a fatty acid-induced upregulation in cholesterol biosynthesis and also plays a role in diabetes-induced hypercholesterolemia.


Subject(s)
Cholesterol , Diabetes Mellitus, Experimental , Hypercholesterolemia , Liver , Peroxisomes , Animals , Cholesterol/biosynthesis , Cholesterol/metabolism , Diabetes Mellitus, Experimental/metabolism , Fatty Acids/metabolism , Hypercholesterolemia/metabolism , Liver/metabolism , Mice , Microbodies/metabolism , Oxidation-Reduction , Peroxisomes/metabolism
6.
Mol Cell Biochem ; 2023 Dec 08.
Article in English | MEDLINE | ID: mdl-38064139

ABSTRACT

The morbidity and mortality rates of cardiovascular diseases (CVDs) are increasing; thus, they impose substantial health and economic burdens worldwide, and effective interventions are needed for immediate resolution of this issue. Recent studies have suggested that noncoding RNAs (ncRNAs) play critical roles in the occurrence and development of CVDs and are potential therapeutic targets and novel biomarkers for these diseases. Newly discovered modes of cell death, including necroptosis, pyroptosis, apoptosis, autophagy-dependent cell death and ferroptosis, also play key roles in CVD progression. However, ferroptosis, which differs from the other aforementioned forms of regulated cell death in terms of cell morphology, biochemistry and inhereditability, is a unique iron-dependent mode of nonapoptotic cell death induced by abnormal iron metabolism and excessive accumulation of iron-dependent lipid peroxides and reactive oxygen species (ROS). Increasing evidence has confirmed that ncRNA-mediated ferroptosis is involved in regulating tissue homeostasis and CVD-related pathophysiological conditions, such as cardiac ischemia/reperfusion (I/R) injury, myocardial infarction (MI), atrial fibrillation (AF), cardiomyopathy and heart failure (HF). In this review, we summarize the underlying mechanism of ferroptosis, discuss the pathophysiological effects of ncRNA-mediated ferroptosis in CVDs and provide ideas for effective therapeutic strategies.

7.
Chem Biodivers ; 20(1): e202200957, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36515624

ABSTRACT

Plant diseases can seriously affect the growth of food crops and economic crops. To date, pesticides are still among the most effective methods to prevent and control plant diseases worldwide. Consequently, to develop potential pesticide molecules, a series of novel 2-phenylglycine derivatives containing 1,3,4-oxadiazole-2-thioethers were designed and synthesized. The bioassay results revealed that G19 exhibited great in vitro antifungal activity against Thanatephorus cucumeris with an EC50 value of 32.4 µg/mL, and in vivo antifungal activity against T. cucumeris on rice leaves at a concentration of 200.0 µg/mL (66.9 %) which was close that of azoxystrobin (73.2 %). Compounds G24 (80.2 %), G25 (89.4 %), and G27 (83.3 %) exhibited impressive in vivo inactivation activity against tobacco mosaic virus (TMV) at a concentration of 500.0 µg/mL, which was comparable to that of ningnanmycin (96.3 %) and markedly higher than that of ribavirin (55.6 %). The antibacterial activity of G16 (63.1 %), G26 (89.9 %), G27 (78.0 %), and G28 (68.0 %) against Xoo at a concentration of 50.0 µg/mL was higher than that of thiadiazole copper (18.0 %) and bismerthiazol (38.9 %). Preliminary mechanism studies on the antifungal activity against T. cucumeris demonstrated that G19 can affect the growth of mycelia by disrupting the integrity of the cell membrane and altering the permeability of the cell. These studies revealed that the amino acid derivatives containing a 1,3,4-oxadiazole moiety exhibited certain antifungal, antibacterial, and anti-TMV activities, and these derivatives can be further modified and developed as potential pesticide molecules.


Subject(s)
Pesticides , Tobacco Mosaic Virus , Antifungal Agents/pharmacology , Antifungal Agents/metabolism , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology , Oxadiazoles/chemistry , Antiviral Agents/pharmacology , Drug Design , Structure-Activity Relationship
8.
Int J Mol Sci ; 24(14)2023 Jul 13.
Article in English | MEDLINE | ID: mdl-37511155

ABSTRACT

Transforming growth factor-ß (TGF-ß)/Smad3 signaling has been shown to play important roles in fibrotic and inflammatory diseases. However, the role of Smad3 in dyslipidemia and non-alcoholic fatty liver disease (NAFLD) in type 2 diabetes remains unclear, and whether targeting Smad3 has a therapeutic effect on these metabolic abnormalities remains unexplored. These topics were investigated in this study in Smad3 knockout (KO)-db/db mice and by treating db/db mice with a Smad3-specific inhibitor SIS3. Compared to Smad3 wild-type (WT)-db/db mice, Smad3 KO-db/db mice were protected against dyslipidemia and NAFLD. Similarly, treatment of db/db mice with SIS3 at week 4 before the onset of type 2 diabetes until week 12 was capable of lowering blood glucose levels and improving diabetic dyslipidemia and NAFLD. In addition, using RNA-sequencing, the potential Smad3-target genes related to lipid metabolism was identified in the liver tissues of Smad3 KO/WT mice, and the regulatory mechanisms were investigated. Mechanistically, we uncovered that Smad3 targeted peroxisome proliferator-activated receptor delta (PPARδ) to induce dyslipidemia and NAFLD in db/db mice, which was improved by genetically deleting and pharmacologically inhibiting Smad3.


Subject(s)
Diabetes Mellitus, Type 2 , Non-alcoholic Fatty Liver Disease , PPAR delta , Smad3 Protein , Animals , Mice , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Liver/metabolism , Mice, Inbred C57BL , Mice, Inbred Strains , Mice, Knockout , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/genetics , PPAR delta/metabolism , Smad3 Protein/metabolism
9.
J Biol Chem ; 296: 100622, 2021.
Article in English | MEDLINE | ID: mdl-33811861

ABSTRACT

Fasting induces lipid accumulation in the liver, while the mechanisms by which fasting dysregulates liver fatty acid oxidation are not clear. Fatty acid ω-oxidation is induced in the fasting state, and administration of dicarboxylic acids to fasting animals decreases plasma ketone bodies. We hypothesized that endogenous dicarboxylic acids might play a role in controlling mitochondrial ß-oxidation in fasting animals. A peroxisome proliferator-activated receptor-alpha agonist and an inhibitor for peroxisomal ß-oxidation were administered to the fasting rats to investigate the role of dicarboxylic acids in liver fatty acid oxidation and lipid homeostasis. We observed that excessive ß-oxidation of endogenous dicarboxylic acids by peroxisomes generated considerable levels of succinate in the liver. Excessive succinate oxidation subsequently increased the mitochondrial NADH/NAD+ ratio and led to an accumulation of 3-OH-CoA and 2-enoyl-CoA intermediates in the liver. This further induced feedback suppression of mitochondrial ß-oxidation and promoted hepatic lipid deposition and steatosis. Specific inhibition of peroxisomal ß-oxidation attenuated fasting-induced lipid deposition in the liver by reducing succinate production and enhancing mitochondrial fatty acid oxidation. We conclude that suppression of mitochondrial ß-oxidation by oxidation of dicarboxylic acids serves as a mechanism for fasting-induced hepatic lipid accumulation and identifies cross talk between peroxisomal and mitochondrial fatty acid oxidation.


Subject(s)
Dicarboxylic Acids/chemistry , Fasting , Ketone Bodies/metabolism , Lipid Metabolism , Liver/metabolism , Mitochondria/metabolism , Peroxisomes/metabolism , Animals , Male , Oxidation-Reduction , Rats , Rats, Sprague-Dawley
10.
Indoor Air ; 32(1): e12956, 2022 01.
Article in English | MEDLINE | ID: mdl-34783390

ABSTRACT

Research on individual level polycyclic aromatic hydrocarbons (PAHs) exposure is scarce. Moreover, the independent contribution of ambient- and indoor-origin PAHs to personal exposure remains poorly studied. We performed simultaneous ambient, residential indoor, and personal exposure measurements in a panel of healthy adults to investigate particle-bound PAHs, focusing on their carcinogenic congeners (cPAHs). Average PAH concentrations were much higher in ambient and residential indoor than personal exposure, with distinct seasonal variations. We employed chrysene as a tracer to investigate residential indoor and personal PAHs exposure by origin. Personal cPAH exposure was largely attributable to ambient-origin exposures (95.8%), whereas a considerable proportion of residential indoor PAHs was likely attributable to indoor emissions (33.8%). Benzo[a]pyrene equivalent (BaPeq) concentrations of cPAH accounted for 95.2%-95.6% of total carcinogenic potential. Uncertainties in estimated PAHs (and BaPeq) exposure and cancer risks for adults were calculated using the Monte Carlo simulation. Cancer risks attributable to ambient, residential indoor, and personal cPAH inhalation exposures ranged from 4.0 × 10-6 to 1.0 × 10-5 . A time-activity weighted model was employed for personal PAH exposure estimations. Estimated cPAH exposures demonstrate high cancer risks for adults in Hong Kong, suggesting that exposure to indoor-generated PAHs should be of great concern to the general population.


Subject(s)
Air Pollutants , Air Pollution, Indoor , Polycyclic Aromatic Hydrocarbons , Adult , Air Pollutants/analysis , Air Pollution, Indoor/analysis , Environmental Monitoring , Hong Kong , Humans , Polycyclic Aromatic Hydrocarbons/analysis , Risk Assessment
11.
Neurol Sci ; 43(5): 3175-3185, 2022 May.
Article in English | MEDLINE | ID: mdl-35000015

ABSTRACT

BACKGROUND AND OBJECTIVE: There are indicates that raphe nuclei may be involved in the occurrence of chronic pain in Parkinson's disease (PD). In the study, we investigated the functional connectivity pattern of raphe nuclei in Parkinson's disease with chronic pain (PDP) to uncover its possible pathophysiology. METHODS: Fifteen PDP, who suffered from pain, lasted longer than 3 months, sixteen Parkinson's disease patients with no pain (nPDP) and eighteen matched normal health controls (NCs) were recruited. All subjects completed the King's Parkinson's Pain Scale (KPPS) besides Parkinson-related scale and demographics. We performed a seed-based resting-state analysis of functional magnetic resonance imaging to explore whole-brain functional connectivity of the raphe nuclei. Multiple regression model was used to explore the related factors of pain including disease duration, disease severity, Hamilton Depression Rating Scale, age, sex, levodopa equivalent dose and the strength of network functional connectivity. RESULTS: Compared with the nPDP, the PDP group showed stronger functional connectivity between raphe nuclei and pain-related brain regions, including parietal lobe, insular lobe, cingulum cortex and prefrontal cortex, and the functional connectivity values of those areas were significantly positively correlated with KPPS independent of the clinical variables. Compared with NCs, the combined PD groups showed decreased functional connectivity including prefrontal cortex and cingulum cortex. CONCLUSIONS: Abnormal functional connectivity model of raphe nuclei may be partly involved in pathophysiological mechanism of pain in PD.


Subject(s)
Chronic Pain , Parkinson Disease , Brain Mapping/methods , Chronic Pain/diagnostic imaging , Chronic Pain/etiology , Humans , Levodopa , Magnetic Resonance Imaging/methods , Neural Pathways , Parietal Lobe , Parkinson Disease/complications , Parkinson Disease/diagnostic imaging , Parkinson Disease/pathology , Raphe Nuclei/pathology
12.
J Cell Mol Med ; 25(12): 5729-5743, 2021 06.
Article in English | MEDLINE | ID: mdl-33949118

ABSTRACT

Cyclosporine A (CsA) is an immunosuppressor widely used for the prevention of acute rejection during solid organ transplantation. However, severe nephrotoxicity has substantially limited its long-term usage. Recently, an impaired autophagy pathway was suggested to be involved in the pathogenesis of chronic CsA nephrotoxicity. However, the underlying mechanisms of CsA-induced autophagy blockade in tubular cells remain unclear. In the present study, we observed that CsA suppressed the activation and expression of transcription factor EB (TFEB) by increasing the activation of mTOR, in turn promoting lysosomal dysfunction and autophagy flux blockade in tubular epithelial cells (TECs) in vivo and in vitro. Restoration of TFEB activation by Torin1-mediated mTOR inhibition significantly improved lysosomal function and rescued autophagy pathway activity, suppressing TEC injury. In summary, targeting TFEB-mediated autophagy flux represents a potential therapeutic strategy for CsA-induced nephrotoxicity.


Subject(s)
Autophagy , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/metabolism , Cyclosporine/toxicity , Epithelial Cells/pathology , Kidney Tubules/pathology , Lysosomes/pathology , TOR Serine-Threonine Kinases/metabolism , Animals , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Immunosuppressive Agents/toxicity , Kidney Tubules/drug effects , Kidney Tubules/metabolism , Lysosomes/drug effects , Lysosomes/metabolism , Male , Mice , Mice, Inbred BALB C , TOR Serine-Threonine Kinases/genetics
13.
J Biol Chem ; 295(30): 10168-10179, 2020 07 24.
Article in English | MEDLINE | ID: mdl-32493774

ABSTRACT

Feeding of rapeseed (canola) oil with a high erucic acid concentration is known to cause hepatic steatosis in animals. Mitochondrial fatty acid oxidation plays a central role in liver lipid homeostasis, so it is possible that hepatic metabolism of erucic acid might decrease mitochondrial fatty acid oxidation. However, the precise mechanistic relationship between erucic acid levels and mitochondrial fatty acid oxidation is unclear. Using male Sprague-Dawley rats, along with biochemical and molecular biology approaches, we report here that peroxisomal ß-oxidation of erucic acid stimulates malonyl-CoA formation in the liver and thereby suppresses mitochondrial fatty acid oxidation. Excessive hepatic uptake and peroxisomal ß-oxidation of erucic acid resulted in appreciable peroxisomal release of free acetate, which was then used in the synthesis of cytosolic acetyl-CoA. Peroxisomal metabolism of erucic acid also remarkably increased the cytosolic NADH/NAD+ ratio, suppressed sirtuin 1 (SIRT1) activity, and thereby activated acetyl-CoA carboxylase, which stimulated malonyl-CoA biosynthesis from acetyl-CoA. Chronic feeding of a diet including high-erucic-acid rapeseed oil diminished mitochondrial fatty acid oxidation and caused hepatic steatosis and insulin resistance in the rats. Of note, administration of a specific peroxisomal ß-oxidation inhibitor attenuated these effects. Our findings establish a cross-talk between peroxisomal and mitochondrial fatty acid oxidation. They suggest that peroxisomal oxidation of long-chain fatty acids suppresses mitochondrial fatty acid oxidation by stimulating malonyl-CoA formation, which might play a role in fatty acid-induced hepatic steatosis and related metabolic disorders.


Subject(s)
Erucic Acids/metabolism , Fatty Liver/metabolism , Liver/metabolism , Malonyl Coenzyme A/biosynthesis , Mitochondria, Liver/metabolism , Peroxisomes/metabolism , Animals , Fatty Liver/pathology , Insulin Resistance , Liver/pathology , Male , Mitochondria, Liver/pathology , Oxidation-Reduction , Peroxisomes/pathology , Rats , Rats, Sprague-Dawley
14.
Cancer Sci ; 112(5): 1839-1852, 2021 May.
Article in English | MEDLINE | ID: mdl-33205567

ABSTRACT

Angiogenesis is closely associated with tumorigenesis, invasion, and metastasis by providing oxygen and nutrients. Recently, increasing evidence indicates that cancer-derived exosomes which contain proteins, coding, and noncoding RNAs (ncRNAs) were shown to have proangiogenic function in cancer. A 26-nt-long ncRNA (X26nt) is generated in the process of inositol-requiring enzyme 1 alpha (IRE1α)-induced unspliced XBP1 splicing. However, the role of X26nt in the angiogenesis of gastric cancer (GC) remains largely unknown. In the present study, we found that X26nt was significantly elevated in GC and GC exosomes. Then, we verified that X26nt could be delivered into human umbilical vein endothelial cells (HUVECs) via GC cell exosomes and promote the proliferation, migration, and tube formation of HUVECs. We revealed that exosomal X26nt decreased vascular endothelial cadherin (VE-cadherin) by directly combining the 3'UTR of VE-cadherin mRNA in HUVECs, thereby increasing vascular permeability. We further demonstrated that X26nt accelerates the tumor growth and angiogenesis in a mouse subcutaneous tumor model. Our findings investigate a unique intercellular communication mediated by cancer-derived exosomes and reveal a novel mechanism of exosomal X26nt in the regulation of tumor vasculature.


Subject(s)
Antigens, CD/metabolism , Cadherins/metabolism , Capillary Permeability , Exosomes/metabolism , Neovascularization, Pathologic/etiology , RNA, Long Noncoding/metabolism , Stomach Neoplasms/blood supply , 3' Untranslated Regions , Animals , Antigens, CD/genetics , Cadherins/genetics , Cell Communication , Cell Movement , Cell Proliferation , Endoribonucleases/metabolism , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Protein Serine-Threonine Kinases/metabolism , Protein Splicing , RNA, Messenger/metabolism , Stomach Neoplasms/metabolism , X-Box Binding Protein 1/metabolism
15.
J Immunol ; 202(4): 1210-1218, 2019 02 15.
Article in English | MEDLINE | ID: mdl-30642982

ABSTRACT

Cadmium (Cd) is an environmental toxin that induces nephrotoxicity. Complement factor H (CFH), an inhibitor of complement activation, is involved in the pathogenesis of various renal diseases. In this study, we investigated the effects of Cd on CFH production by the kidney. In C57B6/J mice, an increased CFH level was found in renal blood and glomerular endothelial cells after Cd treatment. In vitro, Cd induces an increased CFH secretion and mRNA expression in human renal glomerular endothelial cells but not in human podocytes or human mesangial cells. Cd activates the JNK pathway and increases c-Jun and c-Fos in human renal glomerular endothelial cells. A JNK inhibitor, SP600125, specifically abolishes Cd-induced CFH production. By chromatin immunoprecipitation assay and EMSA, the -1635 AP-1 motif on human CFH promoter was identified as the binding element for c-Jun and c-Fos. In a luciferase activity assay, mutation of the AP1 site eliminates Cd-induced increase of CFH promoter activity. Thus, the -1635 AP-1 motif on the CFH promoter region mediates Cd-inducible CFH gene expression.


Subject(s)
Cadmium/pharmacology , Complement Factor H/metabolism , Endothelial Cells/drug effects , Kidney Glomerulus/drug effects , Transcription Factor AP-1/metabolism , Animals , Anthracenes/pharmacology , Binding Sites/drug effects , Cells, Cultured , Complement Factor H/antagonists & inhibitors , Complement Factor H/genetics , Endothelial Cells/metabolism , Humans , Kidney Glomerulus/metabolism , Male , Mice , Mice, Inbred C57BL , RNA, Messenger/antagonists & inhibitors , RNA, Messenger/genetics , RNA, Messenger/metabolism , Transcription Factor AP-1/antagonists & inhibitors , Transcription Factor AP-1/genetics
16.
Neurol Sci ; 42(7): 2937-2946, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33236247

ABSTRACT

BACKGROUND: Patients with akinetic-rigid Parkinson's disease (AR-PD) are more prone to cognitive decline and depressive symptoms than tremor-dominant PD (TD-PD) patients. The right fronto-insular cortex (rFIC), as a key node of salience network, plays a critical role in the switching between central executive network and default mode network. In this study, we explored the functional connectivity mode of rFIC with triple-brain networks, namely default mode network, salience network, and central executive network, in two motor subtypes of PD. METHODS: We recruited 44 PD patients (including the TD-PD group and AR-PD group) and 18 age-matched healthy controls (HCs). We performed functional connectivity (FC) analysis of resting-state functional MRI. RESULTS: Compared with TD-PD, decreased FC were found in the right insular cortex and bilateral anterior cingulate gyrus in AR-PD. Compared with HCs, decreased FC in the bilateral insula, the anterior cingulate gyrus, the precentral gyrus, and the right medial frontal gyrus were found; therein, the FC value of rFIC-precentral gyrus was positively correlated with the Unified Parkinson's Disease Rating Scale-II score in AR-PD (p = 0.0482, r = 0.4162). While TD-PD showed decreased FC in the left insula as well as bilateral anterior cingulate gyrus when compared with HCs, and the FC value of the rFIC-left insula was positively correlated with its Hamilton Depression Rating Scale score (p = 0.02, r = 0.50). CONCLUSION: The functional connectivity mode of rFIC in AR-PD differed from that in TD-PD. The decreased rFIC FC with the other nodes of salience network might be a potential indicator for AR-PD patients prone to develop cognitive decline and depressive symptoms.


Subject(s)
Parkinson Disease , Brain Mapping , Cerebral Cortex/diagnostic imaging , Humans , Magnetic Resonance Imaging , Parkinson Disease/complications , Parkinson Disease/diagnostic imaging , Tremor/diagnostic imaging , Tremor/etiology
17.
Lipids Health Dis ; 20(1): 118, 2021 Sep 29.
Article in English | MEDLINE | ID: mdl-34587955

ABSTRACT

BACKGROUND: The present study was aimed to establish a prediction model for in-stent restenosis (ISR) in subjects who had undergone percutaneous coronary intervention (PCI) with drug-eluting stents (DESs). MATERIALS AND METHODS: A retrospective cohort study was conducted. From September 2010 to September 2013, we included 968 subjects who had received coronary follow-up angiography after primary PCI. The logistic regression analysis, receiver operator characteristic (ROC) analysis, nomogram analysis, Hosmer-Lemeshow χ2 statistic, and calibration curve were applied to build and evaluate the prediction model. RESULTS: Fifty-six patients (5.79%) occurred ISR. The platelet distribution width (PDW), total cholesterol (TC), systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDL-C), and lesion vessels had significant differences between ISR and non-ISR groups (all P < 0.05). And these variables were independently associated with ISR (all P < 0.05). Furthermore, they were identified as predictors (all AUC > 0.5 and P < 0.05) to establish a prediction model. The prediction model showed a good value of area under curve (AUC) (95%CI): 0.72 (0.64-0.80), and its optimized cut-off was 6.39 with 71% sensitivity and 65% specificity to predict ISR. CONCLUSION: The incidence of ISR is 5.79% in CAD patients with DES implantation in the Xinjiang population, China. The prediction model based on PDW, SBP, TC, LDL-C, and lesion vessels was an effective model to predict ISR in CAD patients with DESs implantation.


Subject(s)
Blood Platelets/metabolism , Coronary Artery Disease/blood , Drug-Eluting Stents/adverse effects , Lipids/blood , Aged , Angiography/methods , Calibration , Coronary Artery Disease/diagnosis , Coronary Restenosis , Female , Humans , Male , Middle Aged , Models, Statistical , Multivariate Analysis , Nomograms , ROC Curve , Regression Analysis , Retrospective Studies , Risk
18.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(3): 409-416, 2021 Jun 25.
Article in Zh | MEDLINE | ID: mdl-34180185

ABSTRACT

As the most common active brain-computer interaction paradigm, motor imagery brain-computer interface (MI-BCI) suffers from the bottleneck problems of small instruction set and low accuracy, and its information transmission rate (ITR) and practical application are severely limited. In this study, we designed 6-class imagination actions, collected electroencephalogram (EEG) signals from 19 subjects, and studied the effect of collaborative brain-computer interface (cBCI) collaboration strategy on MI-BCI classification performance, the effects of changes in different group sizes and fusion strategies on group multi-classification performance are compared. The results showed that the most suitable group size was 4 people, and the best fusion strategy was decision fusion. In this condition, the classification accuracy of the group reached 77%, which was higher than that of the feature fusion strategy under the same group size (77.31% vs. 56.34%), and was significantly higher than that of the average single user (77.31% vs. 44.90%). The research in this paper proves that the cBCI collaboration strategy can effectively improve the MI-BCI classification performance, which lays the foundation for MI-cBCI research and its future application.


Subject(s)
Brain-Computer Interfaces , Brain , Electroencephalography , Humans , Imagery, Psychotherapy , Imagination
19.
Environ Res ; 188: 109780, 2020 09.
Article in English | MEDLINE | ID: mdl-32554275

ABSTRACT

Direct evidence about associations between fine particles (PM2.5) components and the corresponding PM2.5 bioreactivity at the individual level is limited. We conducted a panel study with repeated personal measurements involving 56 healthy residents in Hong Kong. Fractional exhaled nitric oxide (FeNO) levels were measured from these subjects. Out of 56 subjects, 27 (48.2%) participated in concurrent outdoor, indoor, and personal PM2.5 monitoring. Organic carbon (OC), elemental carbon (EC), particle bound-polycyclic aromatic hydrocarbons (PAHs), and phthalates were analyzed. Alteration in cell viability, lactic dehydrogenase (LDH), interleukin-6 (IL-6), and 8-isoprostane by 50 µg/mL PM2.5 extracts was determined in A549 cells in vitro. Moderate heterogeneities were shown in PM2.5 exposures and the corresponding PM2.5 bioreactivity across different sample types. Associations between the analyzed components and PM2.5 bioreactivity were assessed using the multiple regression models. Toxicological results revealed that indoor and personal exposure to OC as well as PAH compounds and their derivatives (e.g., Alkyl-PAHs, Oxy-PAHs) induced cell viability reduction and increase in levels of LDH, IL-6, and 8-isoprostane. Overall, OC in personal exposure played a dominant role in PM2.5-induced bioreactivity. Subsequently, we examined the associations of FeNO with IL-6 and 8-isoprostane levels using mixed-effects models. The results showed that per interquartile change in IL-6 and 8-isoprostane were associated with a 6.4% (p < 0.01) and 11.1% (p < 0.01) increase in FeNO levels, respectively. Our study explored the toxicological properties of chemical components in PM2.5 exposure, which suggested that residential indoors and personal OC and PAHs should be of great concern for human health. These findings indicated that further studies in inflammation and oxidative stress-related illnesses due to particle exposure would benefit from the assessment of in vitro PM2.5 bioreactivity.


Subject(s)
Air Pollutants , Air Pollution, Indoor , Polycyclic Aromatic Hydrocarbons , Air Pollutants/analysis , Air Pollutants/toxicity , Air Pollution, Indoor/analysis , Carbon/analysis , Environmental Monitoring , Hong Kong , Humans , Particle Size , Particulate Matter/analysis , Particulate Matter/toxicity , Polycyclic Aromatic Hydrocarbons/analysis
20.
Med Sci Monit ; 26: e922673, 2020 Jun 07.
Article in English | MEDLINE | ID: mdl-32555132

ABSTRACT

BACKGROUND Cell cycle arrest and autophagy have been demonstrated to be involved in various transforming growth factor (TGF)-ß-mediated phenotype alterations of tubular epithelial cells (TECs) and tubulointerstitial fibrosis. But the relationship between cell cycle arrest and the autophagy induced by TGF-ß has not been explored well. MATERIAL AND METHODS The effects of autophagy inhibition on TGF-ß-induced cell cycle arrest in TECs were explored in vitro. Human kidney-2 (HK-2) cells were stimulated by TGF-ß with or without a combined treatment of autophagy inhibitor chloroquine (CQ) or bafilomycin A1 (Baf). RESULTS Autophagy inhibition by CQ or Baf promotes the suppression of growth in TGF-ß-treated HK-2 cells, as detected by the Cell Counting Kit-8 (CCK-8) method. In addition, CQ or Baf stimulation enhances G1 arrest in TGF-ß treated HK-2 cells, as investigated using propidium iodide (PI) staining and flow cytometry, which was further confirmed by a decrease in the expression of phosphorylated retinoblastoma protein (p-RB) and cyclin-dependent kinase 4 (CDK4). The upregulation of p21 induced by CQ or Baf may mediate an enhanced G1 arrest in TGF-ß treated HK-2 cells. Western blot analysis showed that TGF-ß-induced expression of extracellular matrix fibronectin was notably upregulated in the presence of autophagy inhibitors. CONCLUSIONS Inhibition of autophagy sensitizes the TECs to G1 arrest and proliferation suppression induced by TGF-ß that contributes to the induction of tubulointerstitial fibrosis.


Subject(s)
Autophagy/drug effects , Chloroquine/pharmacology , Enzyme Inhibitors/pharmacology , Epithelial Cells/drug effects , G1 Phase Cell Cycle Checkpoints/drug effects , Macrolides/pharmacology , Renal Insufficiency, Chronic/pathology , Transforming Growth Factor beta/pharmacology , Cell Line , Cell Proliferation/drug effects , Cyclin-Dependent Kinase 4/drug effects , Cyclin-Dependent Kinase 4/metabolism , Cyclin-Dependent Kinase Inhibitor p21/drug effects , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Fibronectins/drug effects , Fibronectins/metabolism , Fibrosis , Humans , In Vitro Techniques , Kidney Tubules/cytology , Renal Insufficiency, Chronic/metabolism , Retinoblastoma Protein/drug effects , Retinoblastoma Protein/metabolism
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