Nucleotide-binding oligomerization domain (NOD) proteins are members of a growing family of cytosolic factors related to the apoptosis regulator Apaf-1 and a class of plant disease resistance proteins. NOD proteins have been implicated in the induction of NF-?B activity and in the activation of caspases. Biochemical evidence has unraveled the role of NOD1 and NOD2 as intracellular sensors of bacterial peptidoglycan. Notably, genetic variation in the genes encoding the NOD proteins NOD2, cryopyrin and CⅡTA in humans is associated with inflammatory disease or increased susceptibility to bacterial infections. NOD proteins may be involved in the recognition of microorganisms and regulation of inflammatory responses. [

AIM: To explore the anti-LPS mechanisms of ?-melanocyte-stimulating hormone (?-MSH), the effects of ?-MSH on the expression of SOCS-3 mRNA and the production of NO in murine peritoneal macrophages induced by LPS were investigated. METHODS: BALB/c mouse peritoneal macrophages were cultured in vitro and induced by LPS, ?-MSH and LPS with ?-MSH, respectively. The expression of SOCS-3 mRNA was detected using reverse transcription polymerase chain reaction (RT-PCR). NO produced in macrophages was tested with Griess reagent. RESULTS: The level of NO and the expression of SOCS-3 mRNA were significantly increased in macrophages stimulated with LPS.?-MSH markedly decreased the expression of SOCS-3 mRNA and almost completely inhibited the production of NO induced by LPS. CONCLUSION: These results suggest that the negative regulative circuits operated by SOCS are activated during the inflammation induced by LPS, but SOCS might not be involved in the anti-LPS mechanism of ?-MSH.

0.05) after non-fever limit (non-FL) dose and FL dose endotoxin (ET) was intravenously injected into rabbits. The increase of PGE_2 in CSF was not limited during the occurrence of ET FL. 2. Intracerebroventricular injection (ICV) of different dose of PGE_2 into rabbits induced dose-dependent fever, but there was no more rise in body temperature when the febrile response had reached a certain height. This is termed "PGE FL". 3. The concentration of cyclic adenosine-3′, 5′-monophosphate (cAMP)in CSF paralleled the fluctuation of temperature (r=0.9906, P

40 New Zealand white rabbits were used to observe the effect on the fever caused by ET (endotoxin) and EGTA [ethylene glycol bis-(?-aminoethylethylether)-N, N, N′, N′-tetraacetic acid] after ICV (intracerebroventricular) infusion of Tau and CaCl_2 into rabbits. The results showed that Tau ICV perfusion could inhibit the initial febrile response to ET and EGTA in rabbits (P0.05), which could be blocked by ICV infusion of CaCl_2. The authors suggested that Tau might increase the level of Ca~(++) in the hypothalamus and reduce Na~+/Ca~(++) ratio, then lower the fever.

The effects of intravenous injection of purifed EC on the rectal tempera-ture in normal rabbits and febrile rabbits induced by ET and concentrations of Fe~(2+), Zn~(2+),Cu~(2+) in serum were observed. The results showed that EC could lower the rectal tempera-ture in normal rabbits and also the increased rectal temperature in febrile rabbits. Mean-while, EC could inhibit the formation of the second phase of ET-fever. But EC had noeffect on the changed concentrations of FC~(2+), Zn~(2+), Cu~(2+) in serum caused by ET. Thesefindings suggest that EC may particiate in the regulation of body temperarure under physio-logical and febrile conditions, but not of acute phase response produced by ET.

This experiment was carried out in 65 New Zealand rabbits. The resultsrevealed that the febrile response and increaed PGE_2 level in cerebrospipel fluid (CSF) were significantly reduced when the calcium-channel-blocking agent (verapamil) wasintravenously injected prior to ET. But, verapamil had no marked effect on the increasedcAMP level in csf during ET-induced fever. It was suggested that most likely this anti-pyretic action was due to the effect on biosynthesis of PGE in hypothalamus, while,cAMP might not be involved in the mechanism of this antipyretic action.

AIM: To investigate the role of fibrocystin/polycystin (FPC) in autosomal recessive polycystic kidney disease (ARPKD) development by means of screening the protein interaction using yeast two-hybrid approach. METHODS: The constructed pGBKT7-FPC was used as the bait to screen the pre-transformed human fetal kidney cDNA expression library by yeast two-hybrid assay to obtain the host cell protein which interacted with C-terminal region of FPC. The sequence transformation screening experiment was applied to confirm the protein interactions in yeast. RESULTS: After yeast mating and co-transformation screening analysis, Klotho (KL) was selected from the host cells and the interaction between KL and FPC was further confirmed. CONCLUSION: C-terminal region of FPC can interact with KL, which probably provide the approach for further studying the role and biochemistry mechanism of FPC protein in ARPKD.

Objective To investigate the role of NF-KB binding element in regulation of NOD2. Methods Promoter region of NOD2 containing the NF-κB binding site was amplified by PCR from human genome DNA and correctly connected to the vector pEGFP-N3 which had been cut out promoter by restriction enzyme to obtain the GFP expression vector driven by human NOD2 gene promoter. The constructed plasmids were transiently transferred into cell line HeLa by LipofectAMINETM2000 and the GFP expression was ob- served by the inversion fluorescence microscope. The NF-κB binding site in the constructed vector pEGFP- N3-NOD2wt was deleted by the QuikChange site-directed mutagenesis kit. The recombinant plasmid mpEG- FP-N3-NOD2 was transiently transferred into cell line HeLa by LipofectAMINETM2000, and the GFP expres- sion was observed by the inversion fluorescence microscope. Results The constructed pEGFP-N3-NOD2wt plasmids and mpEGFP-N3-NOD2 were the same as the design confirmed by restriction digestion and se- quence analysis. The results of the cell transient transfection indicated that different strength of GEP ex- pressed by recombinant plasmids in HeLa cells could be observed. The GFP expression of constructed mpEGFP-N3-NOD2 was lower than that of pEGFP-N3-NOD2wt. Conclusion The GFP expression vector driven by human NOD2 gene promoter which contains the NF-κB binding site, and the site deleted plasmid were successfully constructed. The GFP expression of recombinant plasmid mpEGFP-N3-NOD2, deletion of the NF-KB binding site, was obviously weaken in HeLa. The results indicate that NF-KB binding element may play a positive role in regulation of NOD2 gene, which establishes favourable bases for further study on the mechanism of NOD2 gene expression and regulation.

AIM:To investigate the role of fibrocystin/polycystin (FPC) in autosomal recessive polycystic kidney disease (ARPKD) development by means of screening the protein interaction using yeast two-hybrid approach. METHODS:The constructed pGBKT7-FPC was used as the bait to screen the pre-transformed human fetal kidney cDNA expression library by yeast two-hybrid assay to obtain the host cell protein which interacted with C-terminal region of FPC. The sequence transformation screening experiment was applied to confirm the protein interactions in yeast. RESULTS:After yeast mating and co-transformation screening analysis,Klotho (KL) was selected from the host cells and the interaction between KL and FPC was further confirmed. CONCLUSION:C-terminal region of FPC can interact with KL,which probably provide the approach for further studying the role and biochemistry mechanism of FPC protein in ARPKD.

AIM: To observe the effects of ?-MSH on the expression of CD14 and TLR4 mRNA in mou se peritoneal macrophages induced by LPS and explore the mechanisms of ?-MSH ag ainst LPS. METHODS: BALB/C mouse peritoneal macrophages were cultured in the presence of LPS or LPS plus ?-MSH, and the expressions of CD14 and TLR4 mRNA were detected with the m ethod of reverse transcription polymerase chain reaction (RT-PCR). RESULTS: It was found that native murine macrophages o nly expressed a small amount of CD14 and TLR4 mRNA. Both CD14 and TLR4 mRNA expr ession to LPS in mouse macrophages increased significantly than those of contro l group at 6 h and maintained high level until 24 h when they reached to the pea k. Then the expression of CD14 mRNA backed to the normal gene expression baselin e, while TLR4 mRNA had excessive expression at 48 h. In presence of LPS and ?- MSH, the expression of CD14 and TLR4 mRNA decreased remarkably than those of L PS group (P0.05). Only when the dose s of ?-MSH attained to 1, 10 or 100 nmol/L,?-MSH could affect LPS-stimulated e xpression of CD14 and TLR4 mRNA (P0.05). CONCLUSION: These studies suggest that effects of ?-MSH against LPS are associated with its suppressing the critical receptor (CD14 and TLR4) expression of the LPS signal transduction and inhibiting the activation of macrophages.