Olfactory receptors in neural regeneration in the central nervous system

Olfactory receptors are crucial for detecting odors and play a vital role in our sense of smell,influencing behaviors from food choices to emotional memories.These receptors also contribute to our perception of flavor and have potential applications in medical diagnostics and environmental monitoring.The ability of the olfactory system to regenerate its sensory neurons provides a unique model to study neural regeneration,a phenomenon largely absent in the central nervous system.Insights gained from how olfactory neurons continuously replace themselves and reestablish functional connections can provide strategies to promote similar regenerative processes in the central nervous system,where damage often results in permanent deficits.Understanding the molecular and cellular mechanisms underpinning olfactory neuron regeneration could pave the way for developing therapeutic approaches to treat spinal co rd injuries and neurodegenerative diseases like Alzheimer's disease.Olfa ctory receptors are found in almost any cell of eve ry orga n/tissue of the mammalian body.This ectopic expression provides insights into the chemical structures that can activate olfactory receptors.In addition to odors,olfactory receptors in ectopic expression may respond to endogenous compounds and molecules produced by mucosal colonizing microbiota.The analysis of the function of olfactory receptors in ectopic expression provides valuable information on the signaling pathway engaged upon receptor activation and the receptor's role in proliferation and cell differentiation mechanisms.This review explo res the ectopic expression of olfa ctory receptors and the role they may play in neural regeneration within the central nervous system,with particular attention to compounds that can activate these receptors to initiate regenerative processes.Evidence suggests that olfactory receptors could serve as potential therapeutic targets for enhancing neural repair and recovery following central nervous system injuries.

A novel gene delivery system targeting cells expressing VEGF receptors

Two ligand oligopeptides GV1 and GV2 were designed according to the putative binding region of VEGF to its receptors. GV1, GV2 and endosome releasing oligopeptide HA20 were conjugated with poly-L-lysine or protamine and the resulting conjugates could interact with DNA in a noncovalent bond to form a complex. Using pSV2-β-galactosidase as a reporter gene, it has been demonstrated that exogenous gene was transferred into bovine aortic arch-derived endothelial cells (ABAE) andhuman malignant melanoma cell lines (A375) in vitro. In vivo experiments, exogenous gene was transferred into tumor vascular endothelial cells and tumor cells of subcutaneously transplanted human colon cancer LOVO, human malignant melanoma A375 and human hepatoma graft in nude mice. This system could also target gene to intrahepatically transplanted human hepatoma injected via portal vein in nude mice. These results are correlated with theGene delivery system targeting VEGF receptors relevant receptors (flt-1, flk-1/KDR) expression on the targeted cells and tissues.

Expression of P450 and nuclear receptors in normal and end-stage Chinese livers

AIM: To investigate the expression of P450 enzyme genes by using end-stage liver disease samples and trimmed normal Chinese donor livers.

Expression of BMP Receptors in Porcine Granulosa Cells (GCs) and Their Regulation by Luteinizing Hormone (LH)

Bone morphogenetic proteins（BMPs） play critical roles in follicle growth and development.BMPs initiate signaling by assembling BMP receptors and activating Smads,which in turn alter expression of target genes.The mechanism underlying the regulation of the expression of BMP receptors and Smads during follicle development in pigs is still unknown.By quantitative real-time PCR,the mRNA expression of BMP receptors and Smads in granulosa cells（GC） was investigated.Cells were obtained from small porcine follicles（SF;3 mm diameter） and dominant follicles（DF;6 mm diameter）;ActR1A and BMPR2 mRNA levels in DF were significantly higher（P0.05） than that in SF,whereas BMPR1B,Smad4 and Smad7 expression tended to decrease（P0.05）.The levels of BMPR1A,ActR2,Smad1,Smad5,and Smad8 mRNA did not differ between DFs and SFs.To investigate the effect of LH on BMP receptors in GC,cells obtained from porcine DFs were cultured in medium supplemented with different doses of luteinizing hormone（LH）.High doses of LH（4 IU mL-1） significantly decreased the concentration of estradiol（E2） and progesterone（P4） in medium and the expression of Cyp19a1（P450 aromatase,P450arom） and Cyp11a1（cholesterol side-chain cleavage enzyme P450,P450scc）,while significantly increased viable cell numbers and up-regulated expression of cyclin dependent kinase-4（CDK4） and cyclin D2.However,LH had no effect on the expression of BMP receptor genes.Thus,the present study indicates that the expression of members of the BMP signaling pathway in porcine GC is regulated during follicle development and the expression of BMP receptors are not regulated by LH in porcine GCs.

Effect of Curcumin on the Gene Expression of Low Density Lipoprotein Receptors

Objective： To investigate the molecular mechanisms and effective target ponits of lipid-lowering drug, Rhizoma Curcumae Longae, and study the effect of curcumin on the expression of low density lipoprotein （LDL） receptors in macrophages in mice. Methods. Macrophages in mice were treated with curcumin, which was purified from the ethanolly extraction of Rhizoma Curcumae Longae for 24 h. The LDL receptors expressed in the macrophages were determined by enzyme-linked immunosorbent assay （ELISA） and assay of Dil labeled LDL uptake by flow cytometer. Results： It was found for the first time that 10 μmol/L-50 μmol/L curcumin could obviously up-regulate the expression of LDL receptor in macrophages in mice, and a dose-effect relationship was demonstrated. Conclusion： One of the lipid-lowering mechanisms of traditional Chinese medicine, Rhizoma Curcumae Longae, was completed by the effect of curcumin through the up-regulation of the expression of LDL receptor.

THE INCREASE IN PLASMINOGEN ACTIVATOR INHIBITOR TYPE-1 EXPRESSION BY STIMULATION OF ACTIVATORS FOR PEROXISOME PROLIFERATOR-ACTIVATED RECEPTORS IN HUMAN ENDOTHELIAL CELLS

Objective.To investigate the effect of peroxis ome proliferator-activated recept ors(PPARs )activators on plasminogen activator inhibitor ty pe-1(PAI-1)expression in human umbilical vein e ndothelial cells and the possi-ble mechanism.Methods.Human umbilical vein endothelial ce lls(HUVECs )were obtained from normal fetus,and cul-tured conventionally.Then the HUVECs were exposed to test agents(linolenic acid,linoleic acid,oleic acid,stearic acid and prostaglandin J 2 respectively)in varying concentrations with fresh media.RT -PCR and ELISA were applied to determine the expression of PPARs and PAI-1in HUVECs.Results.PPARα,PPARδand PPARγmRNA were detected by using RT-PCR in HUVECs.Treatment of HUVECs with PPARαand PPARγactivators---linolenic acid,linoleic acid,oleic acid and prostaglandin J 2 respectively,but not with stearic a cid could augment PAI-I mRNA expression and protein secretion in a concentration-dependent manner.However,the mRNA expressions of 3subclasses of PPAR with their activators in HUVECs were not changed compared w ith controls.Conclusion.HUVECs express PPARs.PPARs activators may increase PAI-1expression in ECs,but the underlying mechanism remains uncle ar.Although PPARs expression was not enhanced after stimulated by their activators in ECs,the role of functionally active PPARs in regulating PA I-1expression in ECs needs to be further investigated by using transient gen e transfection assay.

Increased Expression of Endothelin Receptors in Human Cirrhosis—— Relationship with Splanchnic Hemodynamics

The purpose of the present study was to assess the correlation that likely exists among increased portal pressure (P p), portal blood flow quantity (Q p) and ET A and ET B receptor mRNA expression in human cirrhosis. In situ hybridization and reverse transcription polymerase chain reactions (RT PCR) were performed to determine the expression of ET A and ET B receptor mRNA in liver tissues from traumatic subjects ( n =10) and cirrhotic patients ( n =15) in whom hepatic hemodynamic values were measured. The expression of the two transcripts was significantly higher in liver samples of cirrhotic patients than in those obtained from traumatic subjects. It has shown that ET A receptor mRNA predominantly located in hepatic stellate cells (HSCs) and vascular smooth muscle cells of intrahepatic arteries and portal veins, ET B receptor mRNA in HSCs, sinusoidal endothelial cells and Kuppfer cells. There was a highly significant direct relationship between ET A and ET B receptor mRNA and P p and Q p in cirrhotic patients. It suggests that liver paracrine endothelin system may be overactivated in human cirrhosis accompanied with increased expression of ET A and ET B receptor mRNA which may play an important role in the pathogenesis and maintenance of splanchnic hyperdynamics.

Intrahepatic expression of genes related to metabotropic receptors in chronic hepatitis

AIM： To screen for genes related to metabotropic re- ceptors that might be involved in the development of chronic hepatitis. METHODS： Assessment of 20 genes associated with metabotropic receptors was performed in liver speci- mens obtained by punch biopsy from 12 patients with autoimmune and chronic hepatitis type B and C. For this purpose, a microarray with low integrity grade and with oligonucleotide DNA probes complementary to target transcripts was used. Evaluation of gene expression was performed in relation to transcript level, correlation between samples and grouping of clinical parameters used in chronic hepatitis assessment. Clini- cal markers of chronic hepatitis included alanine and aspartate aminotransferase, ~,-glutamyltranspeptidase, alkaline phosphatase and cholinesterase activity, levels of iron ions, total cholesterol, triglycerides, albumin, glucose, hemoglobin, platelets, histological analysis of inflammatory and necrotic status, fibrosis according to METAVIR score, steatosis, as well as anthropometric body mass index, waist/hip index, percentage of adi- pose tissue and liver size in ultrasound examination. Gender, age, concomitant diseases and drugs were also taken into account. Validation of oligonucleotide microarray gene expression results was done with the use of quantitative real-time polymerase chain reaction （qRT-PCR）. RESULTS： The highest （0.002 〈 P 〈 0.046） expres- sion among genes encoding main components of metabotropic receptor pathways, such as the a subunit of G-coupled protein, phosphoinositol-dependent pro- tein kinase or arrestin was comparable to that of an- giotensinogen synthesized in the liver. Carcinogenesis suppressor genes, such as chemokine ligand 4, tran- scription factor early growth response protein 1 and lysophosphatidic acid receptor, were characterized by the lowest expression （0.002 〈 P 〈 0.046）, while the factor potentially triggering hepatic cancer, transcrip- tion factor JUN-B, had a 20-fold higher expression. The correlation between expression of genes of protein kinases PDPK1, phosphoinositide 3-kinase and protein kinase A （Spearman＇s coefficient range： 0.762-0.769） confirmed a functional link between these enzymes. Gender （P = 0.0046） and inflammation severity, mea- sured by alanine aminotransferase activity （P = 0.035）, were characterized by diverse metabotropic receptor gene expression patterns. The Pearson＇s coefficient ranging from -0.35 to 0.99 from the results of qRT-PCR and microarray indicated that qRT-PCR had certainlimitations as a validation tool for oligonucleotide mi- croarray studies. CONCLUSION： A microarray-based analysis of hepa- tocyte metabotropic G-protein-related gene expression can reveal the molecular basis of chronic hepatitis.

EXPRESSION OF VEGF RECEPTOR KDR IN DIFFERENT ORIGINATED CARCINOMAS

Objective: To detect the expression of KDR in different originated carcinomas and to explore its expressed ways and the relationship with tumor progression. Methods : KDR cDNA (V VII domains) fragment was cloned from human umbilical vein with RT PCR and was expressed in Ecoli.Jm109. The fusion protein of GST KDR was used for immunizing Balb/c mice to prepare monoclonal antibodies against KDR. The different tumor tissues and related normal tissues were examined with KDR McAb by S P immuno histochemistry. Results: the rate and intensification of KDR expression among different originated cancers are very different, bladder cancers from transmigrated epidermis are 100% positive and highest intensification. The expression of KDR in breast cancer and intestinal cancer lie in the second rate, the weakest expression of KDR is in lung squamous carcinoma. Moreover, expression of KDR in tumor tissues lie both in endothelial cells (EC) of tumor blood vessels and tumor cells. Conclusion: VEGF may be not only the para secretory factor making EC proliferation but also auto secretory factor stimulating the proliferation of tumor cells to benefit the growth and metastasis of malignant tumors. The different expression of KDR in different originated carcinomas may relate with malignant degree of tumor.

GENE EXPRESSION OF GROWTH FACTOR RECEPTORS AND NEURONAL MARKERS IN NEURO BLASTOMA CELL LINES

Gene expression of nerve growth factor receptor (NGFR), epidermal growth factor receptor (EGFR), chromogranin A (CGA) and neuropetide Y (NPY)in 4 aeuroblsstoma cell lines without N-myc amplification was studied by wins Northern blot technique, N type cells expressed more NGFR mRNA than S type cells and have only little or no EGFR expression. S type cells had stronger expression of EGFR mRNA than that of N type cells accompanying with only less or even no NGFR expression. The results Indicated that difference of gene expression of theae growth factor receptors might be due to the various of tumor cell differetiation. Celli differentiating toward neurons gave more NGFR expression and cells prepared to be differentiating toward other direction might give more EGFR gene expression.Various gene expression of CGA and NPY In neuroblsstoma cell lines might be due to the presence of different stages of tumor cell differentiation and NGF only Induced differentiation of those neuroblastoma cells ready to be differentiation to neurons afterwards.

Signal Peptide and Denaturing Temperature are Critical Factors for Efficient Mammalian Expression and Immunoblotting of Cannabinoid Receptors

Many researchers employed mammalian expression system to artificially express cannabinoid receptors, but immunoblot data that directly prove efficient protein expression can hardly be seen in related research reports. In present study, we demonstrated cannabinoid receptor protein was not able to be properly expressed with routine mammalian expression system. This inefficient expression was rescued by endowing an exogenous signal peptide ahead of cannabinoid receptor peptide. In addition, the artificially synthesized cannabinoid receptor was found to aggregate under routine sample denaturing temperatures (i.e.,≥95°C), forming a large molecular weight band when analyzed by immuno-blotting. Only denaturing temperatures ≤75°C yielded a clear band at the predicted molecular weight. Collectively, we showed that efficient mammalian expression of cannabinoid receptors need a signal peptide sequence, and described the requirement for a low sample denaturing temperature in immuno-blot analysis. These findings provide very useful information for efficient mammalian expression and immuno-blotting of membrane receptors.

Expression of prostaglandin E_2 receptors in rat hippocampus

BACKGROUND: Prostaglandin E2 (PGE2) can directly regulate toxic injury of hippocampal neurons through participation by its receptor. Increase of excitability of hippocampal membrane and long-term synaptic elasticity are closely related to PGE2, PGD2 and PGF2A. This suggests that PGE2 may be a key molecule of neuronal signal passage and regulate the existence of neurons through its receptor. However, which isoforms of PGE2 receptor expressing in hippocampal neurons is still unclear. OBJECTIVE: To research the subtype expression of PGE2 receptor in hippocampus of rats through mRNA transcription and protein interpretation. DESIGN: Animal studies with random, control and operator and designer double-blind methods. SETTING: University of South Carolina, Animal Center. MATERIALS: Sprague-Dawley rats, aged 12 weeks, weighing 200 g, females 48 and males 48, were selected from Animal Center in South Carolina University. Tri ReagentTM kit was provided by Molecular Research Center, USA. METHODS: The experiment was carried out in Animal Center in South Carolina University from January to December 2005. The expression of the PGE2 receptors was profiled and compared in rat hippocampus using real-time RT-PCR and Western-blot techniques. MAIN OUTCOME MEASURES: Expression of PGE2 receptors in various isoforms of hippocampal neurons of rats. RESULTS: mRNAs of all four EP1-4 subtypes were detected in the hippocampus. Western-blot data showed consistently detectable bands at approximately Mr 50 000 of EP1, Mr 40 000 and Mr 52 000 of EP2, Mr 45 000, Mr 57 000 and Mr 105 000 of EP3, and Mr 46 000 of EP4. CONCLUSION: Identifying four subtypes of EPs heterogeneously expresses in the hippocampus.

Ontogeny of expression of transforming growth factor-βand its receptors and their possible relationship with scarless or scar-forming healing in human fetal and postnatal skins

Fetal eutaneous wounds that oeeur in earlygestation heal without sear formation.Althoughmueh work has been done to eharaeterize the roleof transforming growth

EFFECT OF rhTGF-β1 AND rhGM-CSF ON RECEPTOR EXPRESSIONS IN J6-1 AND J6-2 LEUKEMIC CELLS

ABC immunoperoxidase was used to test the effects of rhTGF-β1 and rhGM-CSF on receptor expressions in J6-1 and J6-2 leukemic cell lines. Computer assisted image analysis system was introduced to evaluate positive index of time-and dose-dependent specimens. The expression of c-kit was elevated both in positive rate and positive index by TGF-01 in both time- and dose-dependent manners. Ing/ml rhTGF-β1 simultaneously enhanced the expression of c-fms and PDGF-R which is not detected in 50 ng / ml GM-CSF treatment. Endoglin was down-regulated after TGF-β treatment and up-regulated in J6-2 cells after GM-CSF treatment, c-kit Expression was elevated by TGF-β in J6-1 cells while decreased by both in J6-2 cells.

SNP Identification in α_(2A)-Adrenergic Receptor Gene in Chinese and the Effect on Gene Expression

Objective: To scan single nucleotide polymorphism ( SNP ) in Chinese alpha-2Aadrenergic receptor (α_(2A)-AR) gene and study the effects of the SNP on the gene expression.Methods: The complete sequence of α_(2A)-AR gene was analyzed with automated DNA sequencer to scanSNPs. Genomic DNA was extracted from whole blood and a 239 bp fragment containing the G/Cpolymorphism was amplified with PCR using a pair of. specific primers. PCR-RFLP was used to performthe genotyping of the SNP at the site-1 296 bp of the people in the North of China. Electrophoresismobility shift assay ( EMSA ) was used to study the binding of the 390 bp fragments (- 1 414-1 025bp) with G or C at the site-1 296 bp and nuclear extracts . Results: In our study, two SNPs werefound in α_(2A)-AR gene. Allele frequencies of the SNP at the site-1 296 bp were 0.61 and 0.39 forG and C , and the genotype frequencies were 0.34 , 0.54 and 0.13 for GG, GC and CC respectively fromthe people in the North of China. In the EMSA, a specific binding appeared in the complex ofnuclear extracts and DNA with C at-1 296 bp . Conclusion: Two SNPs exist in α_(2A)-AR gene from thepeople in the North of China , and DNA fragment with allele C of the SNP at the site-1 296 bp couldbind with a specific protein, which could influence the gene expression.

Expression and significance of HIF-1α and VEGF in rats with diabetic retinopathy

Objective:To investigate the expression of hypoxia inducible iaclor-1α(HIF-1α)and vascular endothelial growth factor(VECF)in diabelic retinopathy(DR)rats and its effect on the DR occurrence and development.Methods:A total of 120 SD rats were randomly divided into trial group and control group with 60 in each.STZ.i.p.was used in the trial group to establish the DM model,citrate buffer salt of same amount was used up.to the control group.1,3 and 6 months after injection,respective 20 rats were sacrificed in each group to observe expression of HIF-1αand VEGF in the rat retina tissue at different lime points.Results:Expression of HIF-1αand VEGF were negative in the control group;expression of HIF-1αand VKGF protein in retinal tissue were weak after 1 month of DR mold formation.It showed progressive enhancement along with the progression in different organizations,differences between groups were significant(P<0.05).Conclusions:Expressions of HIF-1αand VF.GF were;correlated with disease progression in early diabelic relinopathy.Retinal oxygen can induce over-expression of HIF-1αand VEGF.It shows that HIF-1αand VEGF play an important role in the pathogenesis of DR.

Correlation of human epidermal growth factor receptor 2 expression with clinicopathological characteristics and prognosis in gastric cancer

AIM:To investigate human epidermal growth factor receptor 2(HER2) gene amplification and protein expression in Chinese patients with resectable gastric cancer and the association with clinicopathological characteristics and survival.METHODS:One hundred and ninety-seven gastric cancer patients who underwent curative surgery procedures were enrolled into this study.HER2 gene amplification and protein expression were examined using fluorescence in-situ hybridization(FISH) and immunohistochemistry(IHC) analysis on formalin-fixed paraffinembedded gastric cancer samples from all patients.For scoring,Hofmann's HER2 gastric cancer scoring system was adopted.All cases showing IHC3+ or FISH positiv-ity were defined as HER2 positive.Patient clinicopathological data and survival information were collected.Finally,χ 2 statistical analysis was performed to analyze the HER2 positivity rate amongst the subgroups with different clinicopathological characteristics including;gender,age,tumor location,Lauren classification,differentiation,TNM staging,depth of invasion,lymph node metastases and distant metastasis.The probability of survival for different subgroups with different clinicopathological characteristics was calculated using the Kaplan-Meier method and survival curves plotted using log rank inspection.RESULTS:According to Hofmann's HER2 gastric cancer scoring criteria,31 cases(15.74%) were identified as HER2 gene amplified and 19 cases(9.64%) were scored as strongly positive for HER2 membrane staining(3+),25 cases(12.69%) were moderately positive(2+) and 153 cases(77.66%) were HER2 negative(0/1+).The concordance rate between IHC and FISH analyses was 88.83%(175/197).Thirty-six cases were defined as positive for HER2 gene amplification and/or protein expression,with 24 of these cases being eligible for Herceptin treatment according to United States recommendations,and 29 of these cases eligible according to EU recommendations.Highly consistent results were detected between IHC3+,IHC0/1 and FISH(73.68% and 95.42%),but low consistency was observed between IHC2+ and FISH(40.00%).The positivity rates in intestinal type and well-differentiated gastric cancer were higher than those in diffuse/mixed type and poorly-differentiated gastric cancer respectively(28.57% vs 13.43%,P = 0.0103;37.25% vs 11.64%,P < 0.0001),but were not correlated with gender,age,tumor location or TNM stage,depth of invasion,lymph node metastases and distant metastasis.In poorly-differentiated gastric cancer patients,those without lymph node metastasis showed a higher HER2 positivity rate than those with lymph node metastasis(26.47% vs 7.14%,P = 0.0021).This association was not present in thosepatients with well-differentiated gastric cancer(28.57% vs 43.33%,P = 0.2832).Within our patient cohort,26 cases were lost to follow-up.The median survival time for the remaining 171 patients was 18 mo.The median survival times of the HER2 positive and negative groups were 17 and 18.5 mo respectively.Overall survival was not significantly different between HER2-positive and negative groups(χ 2 = 0.9157,P = 0.3386),but in patients presenting well-differentiated tumors,the overall survival of the HER2-positive group was significantly worse than that of the HER2-negative group(P = 0.0123).In contrast,patients with poorly differentiated and diffuse/mixed subtype gastric cancers showed no significant differences in overall survival associated with HER2.Furthermore,the median survival time of the HER2 positive group did not show any statistically significant differences when compared to the subgroups of gender,age,tumor location,TNM classification,lymph node metastases and distant metastasis.CONCLUSION:Patients with intestinal type gastric cancer(GC),well-differentiated GC and poorly-differentiated GC without lymph node metastasis,may all represent suitable candidates for targeted therapy using Herceptin.

Gene expression of hepatocyte growth factor and its receptor in HCC and nontumorous liver tissues

AIM To study the changes of gene expression of hepatocyte growth factor (HGF) and hepatocyte growth factor receptor (HGFr) in hepatocellular carcinoma (HCC) tissue and nontumorous liver tissue and the relationship between these changes and the biological behavior of the tumor.METHODS Gene expression of HGF and HGFr in 26 cases of HCC tissue and their adjacent nontumorous liver tissues was determined with digoxigenin-labeled DNA probes.RESULTS Positive expression of HGF in HCC tissue was similar to that in the adjacent nontumorous liver tissue, but positive rate of HGF expression was lower than HGFr gene expression. However, HGFr expression was higher in the metastatic cases than in those without metastasis. It was found that HGFr was overexpressed in HCC tissue as well as in the adjacent nontumorous liver tissue.CONCLUSION There seems to be a close relationship between overexpression of HGFr gene and tumor metastasis, and the HGF and HGFr system plays an important role in regulating tumor growth and metastasis.

Betaine inhibits Toll-like receptor 4 expression in rats with ethanol-induced liver injury

AIM:To test whether ethanol feeding could induce Toll-like receptor 4(TLR4)responses,assess the hepatoprotective effect of betaine and its inhibitive effect on TLR4 in animal models of alcoholic liver injury.METHODS:Forty-eight female Sprague-Dawley rats were randomly divided into four groups as control,model,low and high dose betaine groups.Except control group,all rats were fed with high fat-containing diet plus ethanol and fish oil gavages for 8 wk.Betaine was administered intragastrically after exposure of ethanol for 4 wk.The changes of liver histology were examined.The expression of TLR4 mRNA and protein was detected by RT-PCR and Western blotting,respectively.The serum aminotransferase activity alanine transarninase(ALT),aspartate aminotransferase(AST),serum endotoxin,and liver inflammatory factors tumor necrosis factor-α(TNF-α),interferon-γ(IFN-γ),interleukin-18(IL-18)were also assayed.RESULTS:Compared with control group,rats of model group developed marked liver injury,accompanied by an increase of ALT(159.41±7.74 U/L vs 59.47± 2.34 U/L,P<0.0001),AST(248.25±1.40 U/L vs 116.89±3.48 U/L,P<0.0001),endotoxin(135.37± 30.17 ng/L vs 44.15±7.54 ng/L,P<0.0001),TNF-α(20.81±8.58 pg/mL vs 9.34±2.57 pg/mL,P=0.0003),IFN-γ(30.18±7.60 pg/mL vs 16.86±9.49 pg/mL,P= 0.0039)and IL-18(40.99±8.25 pg/mL vs 19.73±9.31 pg/mL,P=0.0001).At the same time,the expression of TLR4 mRNA and protein was markedly induced in the liver after chronic ethanol consumption(1.45±0.07 vs 0.44±0.04,P<0.0001;1.83±0.13 vs 0.56±0.08,P<0.0001).Compared with model group,betaine feeding resulted in significant decreases of ALT(64.93 ±6.06 U/L vs 159.41±7.74 U/L,P<0.0001),AST(188.73±1.11 U/L vs 248.25±1.40 U/L,P<0.0001),endotoxin(61.80±12.56 ng/L vs 135.37±30.17 ng/L,P<0.0001),TNF-α(9.79±1.32 pg/mL vs 20.81± 8.58 pg/mL,P=0.0003),IFN-γ(18.02±5.96 pg/mL vs 30.18±7.60 pg/mL,P=0.0008)and IL-18(18.23±7.01 pg/mL vs 40.99±8.25 pg/mL,P<0.0001).Betaine also improved liver steatosis.The expression levels of TLR4 mRNA or protein in liver tissues were significantly lowered(0.62±0.04 vs 1.45±0.07,P<0.0001;and 0.65±0.06 vs 1.83±0.13,P<0.0001).There was a statistical difference of TLR4 mRNA and protein expression between high-and low-dose betaine groups(0.62±0.04 vs 0.73±0.05,P<0.0001,and 0.65±0.06 vs 0.81±0.09,P<0.0001).CONCLUSION:Betaine can prevent the alcoholinduced liver injury effectively and improve the liver function.The expression of TLR4 increases significantly in ethanol-fed rats and betaine administration can inhibit TLR4 expression.

Cloning and Expression Analysis of cDNA Encoding Or83b-Like Receptor from Helicoverpa assulta

An Or83b-like receptor gene was cloned from antennae of Helicoverpa assulta（Guenée） by using reverse transcription polymerase chain reaction（RT-PCR） and rapid amplification of cDNA ends（RACE）.Sequence analysis revealed that the transcript of the Or83b-like receptor gene from H.assulta consists of 1 946 nucleotides and the open reading frame（ORF） encodes a peptide of 473 amino acids with 7 putative transmembrane domains.Alignment analysis suggested that amino acid sequence of Or83b-like receptor from H.assulta shares high identity with other Or83b family receptors and this gene was hence named as HassOr83b.Tissues expression analysis showed that the HassOr83b transcript is clearly observed in the antennae,labial palps and proboscises,but not in bodies,wings and legs.The further development expression analysis suggested HassOr83b is also expressed in several preadult stages,including early-stage larvae,late-stage larvae and pupae,but not in embryos.Locked nucleic acid（LNA）-based in situ hybridization of antennal section indicated that HassOr83b is expressed in a very large number of antennal cells,which suggests that HassOr83b may play a special role in olfaction in H.assulta.