OBJECTIVE: To investigate the effect of thrombospondin-1 (TSP-1) on apoptosis of human megakaryocytic leukemia cell line Meg-01 and its possible mechanism. METHODS: The expression of CD36 antigen in Meg-01 cells was detected by flow cytometry and immunocytochemistry. Meg-01 cells were cultured for 48 hours with TSP-1 and CD36 antibody FA6-152 at different concentrations. The early apoptosis and activity of caspase-3 were detected by flow cytometry. The effect of TSP-1 on the growth and differentiation of megakaryocytes was investigated by cell counting and CFU-MK culture. RESULTS: The flow cytometry and immunocytochemistry showed that CD36 antigen was expressed on the surface of Meg-01 cells. TSP-1 (5 μg/ml) inhibited the growth of Meg-01 cells, but had unobvious effect on M-07e cells. After addition of CD36 antibody FA6-152 (5, 10, and 25 μg/ml), the inhibition effect of TSP-1 was significantly reduced. TSP-1 (2.5, 5, and 7.5 μg/ml) increased the positive expression of Annexin V (P<0.01) and caspase-3 activity (P<0.01), which indicated that TSP-1 had a significant effect on inducing apoptosis. After addition of CD36 antibody FA6-152 (25 μg/ml), the apoptosis induced by TSP-1 in Meg-01 cells was significantly reduced. TSP-1 (5, 10, and 25 μg/ml) could significantly inhibit the formation of CFU-MK in mouse bone marrow cells, while β-TG could not. CD36 antibody FA6-152 (25 μg/ml) could significantly reduce the inhibition of TSP-1 on CFU-MK. CONCLUSION TSP-1 may induce apoptosis of megakaryocytic leukemia cell line Meg-01 cells via CD36/caspase-3, which provides a potential new drug development and treatment target for clinical treatment of megakaryocytic leukemia.
Animals ; Apoptosis ; CD36 Antigens/metabolism* ; Caspase 3/metabolism* ; Cell Line ; Humans ; Leukemia, Megakaryoblastic, Acute ; Mice ; Thrombospondin 1/pharmacology*

OBJECTIVE: To analyze the molecular polymorphisms of CD36 among 58 blood donors with CD36 deficiency and compare with CD36 positive controls. METHODS: A total of 58 donors with CD36 deficiency during a screening conducted in the laboratory from September 2019 to December 2020 were enrolled as the test group, including 39 males and 19 females, while 120 platelet donors with CD36 positive were randomly selected as the controls, including 76 males and 44 females. All of the subjects were Han nationality. The PCR-SBT method was used to detect coding region of CD36 gene, and molecular mutations were compared with those CD36 positive controls. RESULTS: Among the 58 donors with CD36 deficiency, mutations appears in 32 individuals. The detection rate for type I was 71.43% (5/7), and type II was 51.92% (27/52), while among the 120 controls, mutations appears in 12 donors (10%). In the CD36 antigen-deficient donors, 16 variations were found, in which 329-330 del AC with the highest frequency accounted for 20.69%, followed by 1228-1239 del ATTGTGCCTATT(15.52%) and 1156 C>T(10.34%). Two variations, 198-205 del GATCTTTG and 220 C>T, led to premature termination of translation; four mutations, 329-330 del AC, 560 ins T, 1011-1049 39bp dupl and 1343-1344 ins TCTT, caused translation frame shift; 1228-1239 del ATTGTGCCTATT led to deletion of four amino acids (Ile-Val-Pro-Ile) at sites 410-413 of the peptide chain. The 1140 T>A and 1275 G>A were synonymous mutations, and the other 7 mutations resulted in the substitution of single nucleotide. The platelet expression in the donors of CD36 positive with 329-330 del AC or 1228-1239 del ATTGTGCCTATT mutation (heterozygote) was lower than those CD36 positive individuals without mutations (homozygote). CONCLUSION Multiple gene mutations in the CD36 coding region may cause CD36 deficiency, and the heterozygous individuals with mutations may lead to CD36 antigen reduction or deletion. Mutation is not detected in 44.83% of CD36 deficient individuals, there may be some other reasons for the CD36 antigen deficiency.
Blood Donors ; Blood Platelet Disorders/metabolism* ; Blood Platelets/metabolism* ; CD36 Antigens/metabolism* ; Female ; Genetic Diseases, Inborn ; Humans ; Male

The development of nonalcoholic fatty liver disease (NAFLD) is closely related to the fatty acid (FA) uptake. This study aimed to investigate the effect of Krüppel-like factor 9 (KLF9) on CD36 (typical fatty acid translocase), hepatocellular lipid metabolism as well as the development and progression of nonalcoholic fatty liver. High-fat diet-induced obese C57BL/6J mice and db/db mice were used to test the expression levels of Klf9 and Cd36 in the livers. The primary hepatocytes were isolated from C57BL/6J mice, treated with Ad-GFP, Ad-Klf9, Ad-shCtrl or Ad-shKlf9, and then incubated with oleic acid and palmitic acid for 24 h. Liver-specific knockout of Klf9 mice were established. The protein levels and relative mRNA levels were examined by Western blot and real-time PCR, respectively. Triglyceride content was determined by using an assay kit. Lipid content was determined by Oil Red O staining. The results showed that: (1) Klf9 expression levels were increased in the livers of high-fat diet-induced obese mice and db/db mice, compared to their respective control mice. (2) Adenovirus-mediated overexpression of Klf9 in primary hepatocytes increased Cd36 expression and cellular triglyceride contents. (3) In contrast, adenovirus-mediated knockdown of Klf9 expression in primary hepatocytes by Ad-shKlf9 decreased Cd36 expression and cellular triglyceride contents. (4) Finally, Klf9 deficiency decreased liver Cd36 expression and alleviated fatty liver phenotype of high-fat diet-induced obese mice. These results suggest that KLF9 can regulate hepatic lipid metabolism and development of NAFLD by promoting the expression of CD36.
Animals ; CD36 Antigens/metabolism* ; Diet, High-Fat ; Kruppel-Like Transcription Factors/metabolism* ; Lipid Metabolism ; Liver ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Non-alcoholic Fatty Liver Disease/metabolism* ; Oleic Acid/metabolism*

Cardio-cerebral vascular disease induced by atherosclerosis is a serious cause of human health. The pathogenesis of AS is very complex,and the oxidized low-density lipoprotein( ox LDL) induced foam cells formation is considered to be the most important cytological change in AS. Based on the definition of " TCM chemical biology",we clarified the chemical composition of Ilex hainanensis,the effective substances of I. hainanensis on the activity of anti-AS were screened. Then we found that saponin BF523 had the good inhibitory effect on foam cell formation. In this research,we studied the BF523 as the research object to clarify the molecular target of the active compound of I. hainanensis by foam cell formation model. The results showed that BF523 significantly inhibited the oxidation of ox LDL-induced macrophage foaming and decreased the lipid content in macrophages. BF523 had inhibited the phagocytosis of ox LDL in macrophages by reducing the mRNA and protein levels of scavenger receptor CD36,thereby inhibiting the occurrence and development of AS. These findings not only clarified the mechanism of the inhibition of foam cell formation by saponin BF523,but also provided a useful exploration for the enrichment of the theory of " TCM chemical biology".
Atherosclerosis ; CD36 Antigens ; metabolism ; Cells, Cultured ; Foam Cells ; cytology ; drug effects ; Humans ; Ilex ; chemistry ; Lipoproteins, LDL ; adverse effects

Inhibition of CD36, a fatty acid transporter, has been reported to prevent glucotoxicity and ameliorate high glucose induced beta cell dysfunction. Ezetimibe is a selective cholesterol absorption inhibitor that blocks Niemann Pick C1-like 1 protein, but may exert its effect through suppression of CD36. We attempted to clarify the beneficial effect of ezetimibe on insulin secreting cells and to determine whether this effect is related to change of CD36 expression. mRNA expression of insulin and CD36, intracellular peroxide level and glucose stimulated insulin secretion (GSIS) under normal (5.6 mM) or high glucose (30 mM) condition in INS-1 cells and primary rat islet cells were compared. Changes of the aforementioned factors with treatment with ezetimibe (20 μM) under normal or high glucose condition were also assessed. mRNA expression of insulin was decreased with high glucose, which was reversed by ezetimibe in both INS-1 cells and primary rat islets. CD36 mRNA expression was increased with high glucose, but decreased by ezetimibe in INS-1 cells and primary rat islets. Three-day treatment with high glucose resulted in an increase in intracellular peroxide level; however, it was decreased by treatment with ezetimibe. Decrease in GSIS by three-day treatment with high glucose was reversed by ezetimibe. Palmitate uptake following exposure to high glucose conditions for three days was significantly elevated, which was reversed by ezetimibe in INS-1 cells. Ezetimibe may prevent glucotoxicity in pancreatic β-cells through a decrease in fatty acid influx via inhibition of CD36.
Animals ; Anticholesteremic Agents/*pharmacology ; Antigens, CD36/antagonists & inhibitors/genetics/*metabolism ; Cells, Cultured ; Ezetimibe/*pharmacology ; Flow Cytometry ; Glucose/toxicity ; Insulin/genetics/metabolism/secretion ; Insulin-Secreting Cells/cytology/*drug effects/metabolism ; Male ; Palmitic Acid/metabolism ; RNA, Messenger/metabolism ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species/metabolism ; Real-Time Polymerase Chain Reaction

OBJECTIVETo explore the molecular basis for a CD36 deficiency individual and distribution of CD36 gene mutation in Guangxi population.

METHODSA female individual was studied. CD36 phenotype was detected by monoclonal antibody immobilization of platelet antigens assay (MAIPA) and flow cytometry (FCM). The coding regions of the CD36 gene were sequenced. A DNA-based polymerase chain reaction-sequence specific primer (PCR-SSP) assay was used to verify the identified mutation. Cell lines expressing the mutant and wild-type CD36[CD36(MT) and CD36(WT)] were established, with the expression of CD36 determined by Western blotting. The distribution of CD36 gene mutation was investigated among 1010 unrelated individuals with the PCR-SSP assay.

RESULTSBoth MAIPA and FCM assays showed that the patient had type II CD36 deficiency. DNA sequencing showed that she has carried a heterozygous mutation T538C (Trp180Arg) in the exon 6 of CD36. Sequencing of cDNA clone confirmed that there was a nucleotide substitution at position 538 (538T>C). Western blotting also confirmed that the CD36 did not express on the CD36(MT) cell line that expressed the 538C mutant, but did express on the CD36(WT) cell line. The novel CD36 mutation T538C was further verified with 100% concordance of genotyping results by DNA-based PCR-SSP assay and 1010 unrelated individuals. No CD36 538C allele was detected among the 1010 individuals.

CONCLUSIONThis study has identified a novel CD36 mutation T538C(Trp180Arg)(GenBank: HM217022.1), and established a genotyping method for the novel sequence-specific primer PCR. The novel mutation is rare in Guangxi and can cause type II CD36 deficiency.

Base Sequence ; Blood Platelet Disorders ; genetics ; Blood Platelets ; cytology ; metabolism ; Blotting, Western ; CD36 Antigens ; genetics ; metabolism ; Cells, Cultured ; DNA Mutational Analysis ; DNA Primers ; genetics ; Exons ; genetics ; Female ; Flow Cytometry ; Fluorescent Antibody Technique ; Genetic Diseases, Inborn ; genetics ; Genotype ; Genotyping Techniques ; methods ; Humans ; Middle Aged ; Monocytes ; cytology ; metabolism ; Mutation, Missense ; Polymerase Chain Reaction ; methods

OBJECTIVETo study the effect of Jinlida on changes in expression of skeletal muscle lipid transport enzymes in fat-induced insulin resistance ApoE -/- mice.

METHODEight male C57BL/6J mice were selected in the normal group (NF), 40 male ApoE -/- mice were fed for 16 weeks, divided into the model group (HF), the rosiglitazone group ( LGLT), the Jinlida low-dose group (JLDL), the Jinlida medium-dose group (JLDM), the Jinlida high-dose group (JLDH) and then orally given drugs for 8 weeks. The organization free fatty acids, BCA protein concentration determination methods were used to determine the skeletal muscle FFA content. The Real-time fluorescent quantitative reverse transcription PCR ( RT-PCR) and Western blot method were adopted to determine mRNA and protein expressions of mice fatty acids transposition enzyme (FAT/CD36), carnitine palm acyltransferase 1 (CPT1), peroxide proliferators-activated receptor α( PPAR α).

RESULTJinlida could decrease fasting blood glucose (FBG), cholesterol (TC), triglyceride (TG), free fatty acid (FFA) and fasting insulin (FIns) and raise insulin sensitive index (ISI) in mice to varying degrees. It could also up-regulate mRNA and protein expressions of CPT1 and PPARα, and down-regulate mRNA and protein levels of FAT/CD36.

CONCLUSIONJinlida can improve fat-induced insulin resistance ApoE -/- in mice by adjusting the changes in expression of skeletal muscle lipid transport enzymes.

Animals ; Apolipoproteins E ; deficiency ; genetics ; Blood Glucose ; metabolism ; CD36 Antigens ; genetics ; metabolism ; Carnitine O-Palmitoyltransferase ; genetics ; metabolism ; Dietary Fats ; adverse effects ; metabolism ; Drugs, Chinese Herbal ; administration & dosage ; Humans ; Hypoglycemic Agents ; administration & dosage ; Insulin ; metabolism ; Insulin Resistance ; Lipid Metabolism ; drug effects ; Male ; Metabolic Diseases ; drug therapy ; enzymology ; genetics ; metabolism ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Muscle, Skeletal ; drug effects ; metabolism

OBJECTIVETo investigate the anti-atherosclerosis mechanism of Astragalus mongholicus polysaccharides (APS) by examining its effect on gene expression profiles of the dendritic cells (DCs) from healthy donors.

METHODSPeripheral blood DCs from healthy donors were incubated with 200 mg/L APS overnight, and changes in the gene expression profiles were investigated using microarray technique and RT-PCR.

RESULTSCompared with the control cells, APS-treated DCs showed significantly up-regulated expressions of CD36 (0.97 ± 0.23 vs 5.45 ± 1.14) and IL-27 (1.08 ± 0.22 vs 2.97 ± 0.61) and down-regulated expression of expression of IFI16 (0.98 ± 0.18 vs 0.46 ± 0.11).

CONCLUSIONSAPS can promote the maturation and differentiation of DCs by up-regulating CD36 and IL-27 and down-regulating IFI16, and thus positively affects the occurrence and progression of the atherosclerosis.

Astragalus Plant ; chemistry ; CD36 Antigens ; metabolism ; Cell Differentiation ; Dendritic Cells ; drug effects ; Humans ; Interleukins ; metabolism ; Nuclear Proteins ; metabolism ; Phosphoproteins ; metabolism ; Polysaccharides ; pharmacology ; Transcriptome

CD36 is a membrane glycoprotein that is present on various types of cells, including monocytes, macrophages, microvascular endothelial cells, adipocytes and platelets. Macrophage CD36 participates in atherosclerotic arterial lesion formation through its interaction with oxidized low-density lipoprotein (oxLDL), which triggers signaling cascades for inflammatory responses. CD36 functions in oxLDL uptake and foam cell formation, which is the initial critical stage of atherosclerosis. In addition, oxLDL via CD36 inhibits macrophage migration, which may be a macrophage-trapping mechanism in atherosclerotic lesions. The role of CD36 was examined in in vitro studies and in vivo experiments, which investigated various functions of CD36 in atherosclerosis and revealed that CD36 deficiency reduces atherosclerotic lesion formation. Platelet CD36 also promotes atherosclerotic inflammatory processes and is involved in thrombus formation after atherosclerotic plaque rupture. Because CD36 is an essential component of atherosclerosis, defining the function of CD36 and its corresponding signaling pathway may lead to a new treatment strategy for atherosclerosis.
Animals ; Antigens, CD36/chemistry/genetics/*metabolism ; Atherosclerosis/*metabolism/pathology ; Humans ; Macrophages/metabolism/pathology ; Plaque, Atherosclerotic/*metabolism/pathology

The effect of thymic stromal lymphopoietin (TSLP) on macrophage-derived foam cell formation and the underlying mechanism were studied. Macrophages isolated from C57BL/6 mice were co-cultured in vitro with different concentrations of TSLP or TSLPR-antibody in the presence of oxidized low density lipoprotein (ox-LDL). The effects of TSLP on macrophage-derived foam cell formation were observed by using oil red O staining and intracellular lipid determination. The expression levels of foam cell scavenger receptors (CD36 and SRA) as well as ABCA1 and TSLPR were detected by using RT-PCR and Western blotting. As compared with the control group, TSLP treatment significantly promoted lipid accumulation in macrophages, significantly increased protein expression of CD36 and TSLPR in a dose-dependent manner, and significantly reduced the expression of ABCA1 protein in a dose-dependent manner. No significant differences were noted between the TSLPR-antibody group and the control group. TSLP may down-regulate the expression of cholesterol efflux receptor ABCA1 and up-regulate scavenger receptor expression via the TSLPR signaling pathway, thereby promoting macrophage-derived foam cell formation.
ATP Binding Cassette Transporter 1 ; genetics ; metabolism ; Animals ; Antibodies ; immunology ; pharmacology ; Blotting, Western ; CD36 Antigens ; genetics ; metabolism ; Cells, Cultured ; Cholesterol ; metabolism ; Cholesterol Esters ; metabolism ; Cytokines ; pharmacology ; Dose-Response Relationship, Drug ; Foam Cells ; cytology ; drug effects ; metabolism ; Gene Expression ; drug effects ; Immunoglobulins ; immunology ; metabolism ; Lipoproteins, LDL ; pharmacology ; Macrophages ; cytology ; drug effects ; metabolism ; Mice ; Mice, Inbred C57BL ; Receptors, Cytokine ; immunology ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Scavenger Receptors, Class A ; genetics ; metabolism