Objective To observe whether rabbit blood leptin can leak into the brain after craniocerebral trauma (CCT),and to dynamically detect serum levels of leptin,growth hormone (GH),and insulinlike growth factor-1 (IGF-1),and leptin level in cerebrospinal fluid (CSF) after CCT.Methods The FITC labeled leptin was injected into blood vessels of 15 adult male rabbits after anesthesia.Then 9 rabbits underwent unilateral fluid percussive impact,while 6 rabbits underwent sham operation.Thirty minutes postoperatively,brain tissue was taken to make frozen sections which were used to observe fluorescence labeled leptin range.Thirty three adult male rabbits were randomly divided into serum group,serum-control group,CSF group and CSF-control group.Rabbits in serum group and CSF group received fluid percussive impact,while rabbits in serum-control group and CSF-control group were drilled a 7 mm window in skull.Rabbits in serum group and serum-control group were phlebotomized 2 ml at 1 d,3 d,7 d and 14 d after operation,and rabbits in CSF group and CSF-control group were extracted CSF 0.5 ml at the same time points.Then serum levels of leptin,GH,and IGF-1,and leptin level in CSF were tested by ELISA.Results The fluorescence imaging could be seen in the injured brain tissue of rabbits with CCT,which was more than those in brain tissue of rabbits receiving sham operation.Serum leptin levels of rabbits in serum group at each time point were higher than those in serum-control group.Serum levels of GH and IGF-1 and leptin level in CSF were higher in rabbits with CCT than those in rabbits without CCT at 1 d,3 d and 7 d after operation.Conclusion The blood leptin can leak into the brain after CCT,which can cause increase of blood GH and IGF-1.And the latter may be the endocrine factors promoting fracture healing after CCT.

OBJECTIVETo screen the HIV-1 entry inhibitors targeting HIV-1 gp120 from the IBS natural product database by virtual screening based on the binding mode of the neutralizing antibody VRC01 with HIV-1 gp120 and investigate the anti-viral activities of the inhibitors and their action mechanisms.

METHODSThe binding interaction of the candidate molecules binding gp120 and changes of the binding free energy were analyzed by MM-PBSA calculation. The anti-HIV-1 activities of the tested compounds were detected by HIV-1 pseudotyped virus, laboratory-adapted HIV-1 and a cell-cell fusion assay. The cytotoxicity of the studied molecules was examined by XTT colorimetric assay. The mechanisms of the anti-viral activities of the candidate molecules were analyzed using enzyme-linked immunosorbent assay.

RESULTSA total of 19 molecules with distinct reduction of the binding free energy after binding with gp120 were screened from 40000 molecules. Among them, NC-2 showed anti-HIV-1 activities against HIV-1 pseudotyped virus and laboratory-adapted HIV-1, and was capable of blocking HIV-1 envelope-mediated cell-cell fusion. The IC50 of NC-2 for inhibiting HIV-1IIIB and pseudotyped HIV-1JRFL infection were 1.95∓0.44 µmol/L and 10.58∓0.13 µmol/L, respectively. The results of ELISA suggested that NC-2 could inhibit the binding of HIV-1 gp120 to CD4 without blocking the formation of gp41 six-helix bundle in vitro.

CONCLUSIONThis computer-based virtual screening method can be used to screen HIV-1 entry inhibitors targeting gp120. Using this virtual screening approach combined with anti-viral activity screening, we obtained a potent HIV-1 entry inhibitor NC-2 with novel structure.

Anti-HIV Agents ; pharmacology ; Antibodies, Monoclonal ; pharmacology ; Antibodies, Neutralizing ; pharmacology ; Binding Sites ; Cell Fusion ; Cell Line ; Drug Discovery ; Drug Evaluation, Preclinical ; HIV Antibodies ; pharmacology ; HIV Envelope Protein gp120 ; antagonists & inhibitors ; HIV-1 ; drug effects ; Humans ; Microbial Sensitivity Tests