RESPONSES OF HUMAN FETAL SPLENOCYTES AND THYMOCYTES TO INTERLEUKIN-2: LAK ACTIVITY AND PROLIFERATION

Using cytotoxicity and thymidine uptake assays, we investigated the effects of human recombinant in-terleukin-2 (rIL-2) on the induction of lympholine-activated killer (LAK) activity and cellular proliferation in splenocytes and thymocytes from human fetuses (18-22 weeks). We observed that fetal splenocytes and thymocytes incubated with low doses of rIL-2 (10-100 U ml) developed broad antitumor activity (LAK activity) although the kinetics and magnitudes of the responses were different. It indicated the LAK precursors are present in fetal spleen and thymus. Further, rIL-2 induced a strong proliferative response in splenocytes, but not in thymocytes. On the basis of the findings, we conclude that the responses of fetal splenocytes and thymocytes to IL-2 are different.

Effects of elafibranor on liver fibrosis and gut barrier function in a mouse model of alcohol-associated liver disease

BACKGROUND Alcohol-associated liver disease(ALD)is a leading cause of liver-related morbidity and mortality,but there are no therapeutic targets and modalities to prevent ALD-related liver fibrosis.Peroxisome proliferator activated receptor(PPAR)α and δ play a key role in lipid metabolism and intestinal barrier homeostasis,which are major contributors to the pathological progression of ALD.Meanwhile,elafibranor(EFN),which is a dual PPARαand PPARδagonist,has reached a phase III clinical trial for the treatment of metabolic dysfunctionassociated steatotic liver disease and primary biliary cholangitis.However,the benefits of EFN for ALD treatment is unknown.AIM To evaluate the inhibitory effects of EFN on liver fibrosis and gut-intestinal barrier dysfunction in an ALD mouse model.METHODS ALD-related liver fibrosis was induced in female C57BL/6J mice by feeding a 2.5% ethanol(EtOH)-containing Lieber-DeCarli liquid diet and intraperitoneally injecting carbon tetrachloride thrice weekly(1 mL/kg)for 8 weeks.EFN(3 and 10 mg/kg/day)was orally administered during the experimental period.Histological and molecular analyses were performed to assess the effect of EFN on steatohepatitis,fibrosis,and intestinal barrier integrity.The EFN effects on HepG2 lipotoxicity and Caco-2 barrier function were evaluated by cell-based assays.RESULTS The hepatic steatosis,apoptosis,and fibrosis in the ALD mice model were significantly attenuated by EFN treatment.EFN promoted lipolysis and β-oxidation and enhanced autophagic and antioxidant capacities in EtOH-stimulated HepG2 cells,primarily through PPARαactivation.Moreover,EFN inhibited the Kupffer cell-mediated inflammatory response,with blunted hepatic exposure to lipopolysaccharide(LPS)and toll like receptor 4(TLR4)/nuclear factor kappa B(NF-κB)signaling.EFN improved intestinal hyperpermeability by restoring tight junction proteins and autophagy and by inhibiting apoptosis and proinflammatory responses.The protective effect on intestinal barrier function in the EtOH-stimulated Caco-2 cells was predominantly mediated by PPARδ activation.CONCLUSION EFN reduced ALD-related fibrosis by inhibiting lipid accumulation and apoptosis,enhancing hepatocyte autophagic and antioxidant capacities,and suppressing LPS/TLR4/NF-κB-mediated inflammatory responses by restoring intestinal barrier function.

Study on Lymphocyte Activation and Proliferation Induced by Anti-CD3 McAb

T cell activation and proliferation via CD3-TCR complex were investigated by lymphocyte DNA synthesis in vitro.Several interfering factors were also discussed.The result indicated that lymphocyte activation and proliferation are calciumdependent.A rise of cytoplasmic free Ca2+ quickly following activation with CD3 McAb is mainly due to intracellular mobilization of Ca2+,while lymphocyte proliferation needs both intracellular mobilization of Ca2+ as well as influx of extracellular Ca2+, It was confirmed that CTX sensitive G protein plays a role in regulating T cell proliferation by pretreatment with CTX suppressing lymphocyte H-TdR incorporation obviously.PLC and PKC inhibitor neomycin and P.S.S could also decrease T cell proliferation.

Association of β3 Adrenergic Receptor and Peroxisome Proliferator-activated Receptor Gamma 2 Polymorphisms With Insulin Sensitivity:A Twin Study

Objective To study the effect of β3 adrenergic receptor （β3AR） Trp64Arg and peroxisome proliferator activated receptor gamma 2 （PPAR72） Prol2Ala polymorphisms on insulin resistance. Methods One hundred and eight dizygotic twin pairs were enrolled in this study. Microsatellite polymorphism was used to diagnose zygosity of twins. Insulin sensitivity was estimated with logarithm transformed homeostasis model assessment （HOMA）. PCR-RFLP analysis was performed to detect the variants. As a supplement to the sib-pair method, identity by state （IBS） was used to analyze the association of polymorphisms with insulin sensitivity. Results The genotype frequencies of Trp64Trg, Trp64Arg, and Arg64Arg were 72.3%, 23.8%, and 3.9%, respectively, while the genotype frequencies of Pro12Pro, Pro12Ala, and Ala12Ala were 89.9%, 9.6%, and 0.5%, respectively. For β3AR Trp64Arg the interclass co-twin correlations of Waist-to-hip ratio （WHR）, blood glucose （GLU）, and insulin （INS）, homeostasis model assessment insulin resistance index （HOMA-IR） of the twin pairs sharing 2 alleles of IBS were greater than those sharing 0-1 allele of IBS, and HOMA4R had statistic significance. For PPAR3t2 Prol2Ala most traits of twin pairs sharing 2 alleles of IBS had greater correlations and statistic significance in body mass index （BMI）, WHR, percent of body fat （PBF） and GLU, but there were low correlations of either insulin or HOMA-IR of twin pairs sharing 1 or 2 alleles of IBS. The combined effects of the two variations showed less squared significant twin-pair differences of INS and HOMA-IR among twins sharing 4 alleles of IBS. Condusions β3AR Trp64Arg and PPAR）,2 Pro 12Ala polymorphisms might be associated with insulin resistance and obesity, and there might be slight synergistic effects between this two gene loci, and further studies are necessary to confirm this finding.

Down-regulated expressions of PPAR_γ and its coactivator PGC-1 are related to gastric carcinogenesis and Lauren's classification in gastric carcinoma

Objective： To explore the relationship between peroxisome proliferator activated receptor-gamma （PPARγ） and peroxisome proliferator-activated receptor-gamma coactivator-1 （PGC-1） expression in gastric carcinoma （GC）, and analyze their correlations with clinicopathological features and clinical outcomes of patients. Methods：The two-step immunohistochemical method was used to detect the expression of PPARγ and PGC-1 in 179 cases of GC, and 108 cases of matched normal gastric mucosa. Besides, 16 cases of fresh GC specimens and corresponding normal gastric mucosa were detected for PGC-1 expression with Western blotting. Results： The positive rates of PPART and PGC-1 expression were significantly lower in GC （54.75%, 49.16%） than in normal gastric mucosa （70.37%, 71.30%）, respectively （P〈0.05）. The decreased expression of PGC-1 in GC was confirmed ha our Western blot analysis （P=0.004）. PPAR7 and PGC-1 expressions were related to Lauren＇s types ofGC （P〈0.05）. Positive correlation was found between PPART and PGC-1 expression in GC （rk=0.422, P〈0.001）. The survival time of PPART negative and positive patients was 36.6±3.0 vs. 38.5_＋2.7 months, and no statistical difference was found between the 5-year survival rates of two groups （34.4% vs. 44.1%, P=0.522, log-rank test）; the survival time of PGC-1 negative and positive patients was 36.2±2.8 vs. 39.9±2.9 months, while no statistical difference was found between the 5-year survival rates of the two groups （32.0% vs. 48.2%, P=0.462, log-rank test） Conclusions＇. Decreased expression of PPARγand PGC-1 in GC was related to the Lauren＇s classification. Their expressions in GC were positively correlated, indicating that their fimctions in gastric carcinogenesis may be closely related.

Influence of Ciglitazone on A549 Cells Growth in vitro and in vivo and Mechanism

The effect and mechanism of the ciglitazone on lung cancer cells A549 growth in vitro and in vivo were studied. Various concentrations of ciglitazone were added to the cultured A549 line, and the proliferation and differentiation of A549 cells were examined by MTT and cytometry analysis. A549 cells （1 × 10^6/mouse） were inoculated subcutaneously into 20 nude mice, which were randomly divided into two groups., the control group, the ciglitazone treated group. The weights of subcutaneous tumors were measured, The expression of cyclin D1 and P21 in the lung was detected by immohistochemistry and Western blot respectively. The results showed that the proliferation of A549 was inhibited significantly by ciglitazone in a dose- and time-dependent manner. There were more ceils arrested in G1/G0 phase and the expression of PPARγ was markedly upregulated in ciglitazone-treated group. Direct injection of ciglitazone into A549-induced tumors could suppress tumor growth in nude mice and the growth inhibitory rate was 36 %. The expression of cyclin D1 was decreased and P21 increased significantly in ciglitazone-treated group as compared with control group. It was concluded that ciglitazone could inhibit A549 proliferation dose-dependently and time-dependently and induce differentiation, ,which might be related to the modulation of cell cycle interfered by PPARγ.

Dual therapy of rosiglitazone/pioglitazone with glimepiride on diabetic nephropathy in experimentally induced type 2 diabetes rats

Diabetic nephropathy is a major cause of end-stage renal disease （ESRD） in the general population. It is estimated that diabetic nephropathy will eventually develop in about 40% of all patients with diabetes; therefore, prevention is critical for delaying the development and progression of diabetic kidney disease. Despite extensive efforts, medical advances are still not successful enough to prevent the progression of the disease. In the present study, we focused on the comparison of combination therapies and whether they offered additional renoprotection. Type 2 diabetes mellitus was induced by intraperitoneally administering streptozotocin （90 mg/kg） in neonatal rats and then these rats were treated with rosiglitazone （1.0 mg/kg） in combination with glimepiride （0.5 mg/kg） or with pioglitazone （2.5 mg/kg） in combination with glimepiride （0.5 mg/kg）. Diabetic nephropathy markers were evaluated by biochemical and ELISA kits and renal structural changes were examined by light microscopy and transmission electron microscopy. Results show that the combination of pioglitazone with glimepiride is more effective in amelioration of diabetic nephropathy than rosiglitazone with glimepiride drug therapy due to glycemic control, suppressing albumin excretion rate, total protein excretion rate and augmented TNF-α signaling during the development of streptozotocin induced type 2 diabetic nephropathy.

Curcumin inhibits beta-amyloid protein 40/42 expression in the brain in a concentration-and time-dependent manner

Several studies have demonstrated that the amount of beta-amyloid （Aβ） protein in the brain can be lowered by down-regulating Aβ production, promoting Aβ degradation, reducing Aβ oligomerization or deposition, thereby alleviating symptoms of Alzheimer＇s disease. Curcumin has been known to be a peroxisome proliferator activated receptor gamma （PPARy） agonist and can obviously inhibit Aβ production and oligomerization. This study investigated the effects of curcumin on the G-site APP cleaving enzyme 1 （BACE1） activity and PPARy expression in human neuroblastoma SH-SY5Y cells, and validated the inhibitory effects of curcumin on Aβ40/42 expression in the brain. Results revealed that PPARy mRNA and protein expression in the human neuroblastoma SH-SY5Y cells significantly increased with increasing curcumin concentration and time course （P 〈 0.05）; BACE1 mRNA and protein expression and Aβ40/42 production significantly decreased with increasing curcumin concentration and time course （P 〈 0.05）. The changes in PPARy and BACE1 expression during Aβ production could be reversed by the PPARy antagonist GW9662. These findings indicate that curcumin reduced Aβ production by activating PPARy expression and inhibiting BACE1 expression in a concentration- and time-dependent manner.

Neuronal PPARαdeficiency-induced axonal mitochondrial transport defects underly isch⁃emic stroke pathology

OBJECTIVE Peroxisome proliferator activated receptor alpha(PPARα)is an important protective factor in neurovascular diseases such as ischemic stroke.Although PPARαexpression is higher in neurons than astrocytes and microglia,the pathophysiological functions of neuronal specific-PPARαin isch⁃emic stroke remains unknown.Here,we report that neuronal PPARαdeficiency is a key factor of neuronal injury.PPARαexpression markedly decreased in neurons after ischemic stroke.METHODS AND RESULTS Neuronal-specific PPARαknockout(NCKO)exacerbates neuronal damage and brain ischemic injury.PPARαdefi⁃ciency disrupts axonal microtubule organization and mitochondrial transport by decreasing the expression of dynein light chain Tctex-type 1(Dynlt1),which is implicated in cytoprotective role with damaged neurons.Furthermore,resto⁃ration of Dynlt1 expression in neurons of NCKO mice rescue mitochondrial transport disorder,cognitive deficits and brain ischemic injury asso⁃ciated with PPARαdeletion.CONCLUSION These results reveal a critical role for neuronal PPARαin ischemic brain injury by modulating axonal mitochondrial transportation.

Identification and Expression of PPAR in Sinonovacula constricta and Their Potential Regulatory Effects on Δ6 Fad Transcription

Peroxisome proliferator activated receptors(PPAR)are kinds of key transcriptional factors in regulating LC-PUFA biosynthesis.Until now,little is known about PPAR in marine molluscs as well as in other invertebrates.Sinonovacula constricta is the first marine mollusc that is proved to possess the complete LC-PUFA biosynthetic pathway,and it can be a perfect representative to clarify this situation.In this study,the molecular properties of S.constricta PPAR were characterized,and corresponding potential regulatory roles in S.constrictaΔ6 fatty acyl desaturase(Fad)transcription were estimated by dual luciferase assay.Results showed that two PPAR homologs(PPAR_a and_b)were identified in S.constricta.They both contain typical features of vertebrate PPAR,suggesting highly conserved functional regions in PPAR.By phylogenetic comparison,they are clearly different with vertebrate PPAR and can be divided into two distinctive sub-groups.Moreover,they show a high expression level in gill,labial palps,mantle and intestine.Their down-regulated expressions in trochophore larva and veliger larva might be attributed to food-deprivation.Additionally,the transcriptional activity of S.constrictaΔ6 Fad promoter was significantly activated by both PPAR_a and_b,indicating that S.constricta PPAR might play a role in the regulation of LC-PUFA biosynthesis.To our knowledge,this is the first systematic analysis of PPAR in a marine mollusc.The results will provide a valuable reference for further researches on the function of marine molluscan PPAR and their underlying mechanisms in regulating LC-PUFA biosynthesis.

Gut-brain crosstalk regulates craving for fatty food

Patients undergoing Roux-en-Y gastric bypass(RYGB)surgery elicit striking loss of body weight. Anatomical restructuring of the gastrointestinal(GI) tract, leading to reduced caloric intake and changes in food preference, are thought to be the primary drivers of weight loss in bariatric surgery patients. However, the mechanisms by which RYGB surgery causes a reduced preference for fatty foods remain elusive. In a recent report, Hankir et al described how RYGB surgery modulated lipid nutrient signals in the intestine of rats to blunt their craving for fatty food. The authors reported that RYGB surgery restored an endogenous fat-satiety signaling pathway, mediated via oleoylethanolamide(OEA), that was greatly blunted in obese animals. In RYGB rats, high fat diet(HFD) led to increased production of OEA that activated the intestinal peroxisome proliferation activator receptors-α(PPARα). In RYGB rats, activation of PPARα by OEA was accompanied by enhanced dopamine neurotransmission in the dorsal striatum and reduced preference for HFD. The authors showed that OEA-mediated signals to the midbrain were transmitted via the vagus nerve. Interfering with either the production of OEA in enterocytes, or blocking of vagal and striatal D1 receptors signals eliminated the decreased craving for fat in RYGB rats. These studies demonstrated that bariatric surgery led to alterations in the reward circuitry of the brain in RYGB rats and reduced their preference for HFD.

Investigating mechanism of Jiang-zhi-dai-pao-cha for treatment of hyperlipidemia by network pharmacology

Objective:To collect the main components and targets of Jiang-zhi-dai-pao-cha(JZDPC)and investigate the mechanism of JZDPC for the treatment of hyperlipidemia by network pharmacology.Methods:The components and targets of JZDPC were searched from ETCM databases,the targets related to hyperlipidemia were searched from DisGeNET and GeneCards databases,and then the intersection targets and corresponding key components were obtained.Cytoscape 3.8.2 software was used to construct and analyze networks,and then Metascape online database was applied for gene ontology(GO)enrichment analysis and Kyoto Encyclopedia of genes and genomes(KEGG)pathway enrichment analysis of core putative targets.Results:There were 99 overlapping targets between JZDPC and hyperlipidemia,among which NR3C1,ESR1,NR1I2,NFKB1,ESR2,ALOX5,PTGS1,PPARA,RXRA,LPL,PLA2G1B,PYGM,CYP2C9 were the core putative targets,and many members of nuclear receptor 1(NR1)subfamily were included.The core components of JZDPC,such as Ursolic Acid,β-Sitosterol,Resveratrol,Arirubic Acid,Alisol A,Oleanolic Acid,Rhein,Chrysophanol and Emodin,can regulate blood lipid by regulating a series of signaling pathways including the above core potential targets,such as non-alcoholic fatty liver disease(NAFLD)signaling pathway,pathways in cancer,arachidonic acid(AA)metabolism signaling pathway and peroxisome proliferator activated receptor(PPAR)signaling pathway,Starch and sucrose metabolism signaling pathway,etc.They play many roles in the treatment of hyperlipidemia by participating in lipid synthesis and metabolism,anti inflammation,anti oxidative stress,regulating hormone levels and carbohydrate metabolism.Conclusion:Network pharmacology provides a theoretical basis for investigating the mechanism of action of JZDPC,and the NAFLD signaling pathway is one of the most valuable pathways.

Design,synthesis and evaluation of PPAR gamma binding activity of 2-thioxo-4-thiazolidinone derivatives

We designed and synthesized a series of 2-thioxo-4-thiazolidinone derivatives and evaluated them on peroxisome proliferator activated receptor γ（PPARγ） binding activities.Through the biological assays,compounds 18 and 38 were highlighted with K_i values of 12.15 nmol/Land 14.46 nmol/L,respectively.Then structure-activity relationship（SAR） was analyzed to screen privileged structural modifications.Moreover,molecular fitting of these compounds onto the approved drug Rosightazone in the PPARγligand binding domain was performed to elucidate the SAR and explore potential receptor-ligand interactions.These results demonstrate that the 2-thioxo-4-thiazolidinones can be considered as new promising molecular probes with excellent binding activities to PPARγ.

Proliferation of renal mesangial cells induced by very low density lipoprotein is mediated by p42/44 mitogen activated protein kinase

Background The plasma concentration of very low density lipoprotein （VLDL） is negatively correlated to renal function in glomerular diseases. Effects of VLDL on renal function have been partially attributed to the proliferation of mesangial cells. This study examined the potential role of the p42/44 mitogen activated protein kinase （MAPK） in mesangial cell proliferation induced by VLDL. Methods Mesangial cells were treated with VLDL at different concentrations or for different time. The cell cycle of the mesangial cells was analyzed by Xl-r assay and flow-cytometry; MAPK activity was also assayed. In some experiments, cells were treated with VLDL together with or without 0.1 pmol/L PD 98059. Results Ten to 500 μg/ml VLDL stimulated the proliferation of mesangial cells cultured in vitro in a concentration-dependent manner. The effect was associated with an increase in p42/44 MAPK activity. Increased proliferation of mesangial cells by VLDL was significantly attenuated by PD98059, a specific p42/44 MAPK inhibitor. Conclusion These results indicate that the p42/44 MAPK pathway is an important regulator of mesangial cell proliferation and of renal functions.

A novel vanadium complex VO(p-dmada)inhibits neuroinflammation induced by lipopolysaccharide

Uncontrolled microglial activation is decisively involved in the neuroinflammatory pathogenesis of brain diseases. Consequently, suppression of microglial overactivation appears to be a strategy for the prevention of nerve injury. In this paper, a novel vanadium complex, vanadyl N-(p-N,Ndimethylaminophenylcarbamoylmethyl)iminodiacetate(VO(p-dmada)), was synthesized from vanadyl sulfate and N,N-dimethyl-p-phenylenediamine, which was structurally characterized by Fourier transform infrared spectrum and ESI-MS analysis. The effect of VO(p-dmada) on neuroinflammation was investigated by using the models of lipopolysaccharide(LPS)-induced BV2 microglial cells and BALB/c mice.Our data demonstrated that VO(p-dmada) significantly suppressed microglial activation by downregulating inflammatory mediators and associated proteins, and inactivating nuclear factor-κ B(NF-κ B) signaling pathway. VO(p-dmada) also upregulated peroxisome proliferator activated receptor gamma(PPARγ) by reducing transglutaminase 2 and heat shock protein 60 expression. Co-treatment with PPARγ antagonist GW9662 significantly impeded the inhibitory effect of VO(p-dmada) on LPS-induced neuroinflammation.These cumulative findings demonstrated that VO(p-dmada) is a potential new drug for the treatment of neuroinflammation-related neurodegenerative diseases.

Effects of peroxisome proliferator-activated receptor-β/δ on sepsis induced acute lung injury

Background Acute lung injury （ALI） and acute respiratory distress syndrome （ARDS） are the first steps in the development of multiple organ failure induced by sepsis.A systemic excessive inflammatory reaction is currently the accepted mechanism of the pathogenesis of sepsis.Several studies have suggested a protective role of the peroxisome proliferator activated receptor-β/δ （PPAR-β/δ） in related inflammatory diseases.But the role of PPARβ/δ in ALI remains uncertain.The aim of this study was to investigate the role and possible mechanism of PPARβ/δ in ALI induced by sepsis.Methods Cecal ligation and puncture （CLP） was used as a sepsis model.Rats were randomly divided into four groups,the control group （CON,n=6）,sham-operation group （SHAM,n=12）,cecal ligation and puncture group （CLP,n=30）,GW501516 group （CLP＋GW,n=25）,which underwent CLP and were subcutaneously injected with the PPAR-β/δ agonist GW501516 （0.05 mg/100 g body weight）.Survival was monitored to 24 hours after operation.Blood pressure,serum creatinine,blood urea nitrogen,aspartate aminotrasferase and alanine aminotrasferase were measured after CLP.Concentrations of tumor necrosis factor α （TNF-α） and interleukin （IL）-1β in serum were detected by enzyme linked immunosorbent assay （ELISA） kits.Lung tissue samples were stained with H＆E and scored according to the degree of inflammation.Bacterial colonies were counted in the peritoneal fluid.Alveolar macrophages were cultured and incubated with GW501516 （0.15 μmol/L） and PPARβ/δ adenovirus and then treated with Lipopolysaccharide （2 μg/ml） for 2 hours.The TNF-α,IL-1β and IL-6 RNA in lung and alveolar macrophages were determined by real-time PCR.Phosphorylation of signal transducer and activator of transcription 3 （STAT3） in lung and alveolar macrophages was detected by Western blotting.Results GW501516 significantly increased the survival of septic rats,decreased histological damage of the lungs,reduced inflammatory cytokines in serum and lung tissues of septic rats and did not increase counts of peritoneal bacteria.In vitro,GW501516 and over-expression of PPARβ/δ attenuated gene expression of TNF-α,IL-1β and IL-6 in alveolar macrophages.Both in vivo and in vitro,PPARβ/δ inhibited the phosphorylation of STAT3.Conclusion PPARβ/δ plays a protective role in sepsis induced ALI via suppressing excessive inflammation.

Effect of dexamethasone on peroxisome proliferator activated receptor-gamma mRNA expression in 3T3-L1 adipocytes with the human recombinant adiponectin

Background The fat derived protein adiponectin plays an important role in the regulation of glucose metabolism. The aim of this study was to provide the experimental basis for further investigating on adiponectin （ADPN） function. Its eukaryotic recombinant was constructed and expressed in precursor cells of 3T3-L1 adipocytes. The effects of dexamethasone on peroxisome proliferator activated receptor-gamma （PPAR-y） mRNA expression in 3T3-L1 cells with human recombinant adiponectin were assessed. Methods The recombinant plasmid pMD18-T-hADPN and eukaryotic expression vector pcDNA3.1^＋ were digested by two restrictive endonucleases and adiponectin and linear pcDNA3.1^＋ were obtained. Then, they were ligated and translated into JM109. The recombinant pcDNA3.1^＋-hADPN so obtained was identified by digestion by restrictive endonuclease and nucleotide sequencing. The 3T3-L1 precursor cells were transfected using SuperFect Transfection Reagent （Qiagen）. Furthermore, 3T3-L1 cells with human recombinant adiponectin incubated with dexamethasone （0.5 mmol/L） for 24 hours, cells were collected and total RNA was extracted. The PPAR-γ mRNA expression was quantified by semiquantitative reverse transcription-polymerase chain reaction （RT-PCR）. Results After eukaryotic recombinant was digested by Hind Ⅲ and EcoR Ⅰ, fragments of 800 bp and 5.4 kb were identified by nucleotide sequence scanning and consistent with theoretical values. Electrophoretogram of RT-PCR in 3T3-L1 precursors showed only one band in front of 250 bp, which was consistent with theoretical value 234 bp. In the 3T3-L1 cells, 3T3-L1 cells with plasmid and 3T3-L1 cells human recombinant adiponectin, treatment with dexamethasone （0.5 mmol/L） decreased PPAR-y mRNA expression compared to untreated controls （P〈0.01）. Effect of dexamethasone on PPAR-γ mRNA expression in 3T3-L1 cells was reversed by stably transfected human recombinant adiponectin. Conclusion The 3T3-L1 cells stably transfected human recombinant adiponectin had increased PPAR-γ mRNA expression. Dexamethasone suppressed PPAR-γ mRNA expression in the 3T3-L1 cells. Effect of dexamethasone on PPAR-γ mRNA expression in 3T3-L1 cells was reversed by stably transfected human recombinant adiponectin.

Effect of Porous Activated Charcoal Reinforcement on Mechanical and In-Vitro Biological Properties of Polyvinyl Alcohol Composite Scaffolds

The present work focused on developing an innovative composite material by reinforcing polymer matrix with highly porous activated charcoal. Polyvinyl alcohol-activated charcoal（PVA-AC） composite scaffolds were developed by varying the AC concentrations（0, 0.5, 1, 1.5, 2 and 2.5 wt%） in PVA matrix by freeze drying method. The developed scaffolds were characterized for their physicochemical, mechanical and in-vitro biological properties. In addition, the effect of AC on the attachment, proliferation and differentiation of osteoblast MG 63 cells was evaluated by scanning electron microscopy（SEM）, 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay, alkaline phosphatase（ALP） activity assay and alizarin red stain-based（ARS） assay. All the PVA-AC composite scaffolds exhibited good bioactivity, hemocompatibility and protein adsorption properties. The scaffolds with high AC concentration（2.5 wt%） showed controlled drug release kinetics that are suitable for long term healing. The mechanical properties of all the PVA-AC composite scaffolds were improved when compared to the pure PVA scaffold. The high porosity, swelling degree and hydrophilicity of PVA-AC composite scaffolds facilitated cell attachment and proliferation. This is due to porous AC present in the sample that supported the osteoblast differentiation and formed mineralized nodules without the addition of any extra agents. From the above studies, it can be concluded that PVA-AC composite scaffolds are promising biomaterials for bone tissue engineering applications.