ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of farnesoid-X-receptor (FXR) antagonist Z-guggulsterone in an in vivo high-fat fed apolipoprotein E knockout (ApoE(-/-)) mice model of myocardial ischemia/reperfusion (I/R).</p><p><b>METHODS</b>Male ApoE(-/-) mice were randomly divided into three groups: standard ApoE(-/-) group (fed with standard mouse diet for 12 weeks before myocardial I/R procedure, n = 18), high-fat ApoE(-/-) group (fed with high-fat mouse diet for 12 weeks before myocardial I/R procedure, n = 22), and high-fat ApoE(-/-) + FXR antagonist group(fed with high-fat mouse diet for 12 weeks and received FXR antagonist Z-Guggulsterone 30 minutes before myocardial I/R procedure, n = 17). The expression of FXR was detected by real-time quantitative-PCR. Myocardial infarct size was determined by Evans blue/TTC double staining methods. Myocardial apoptosis was determined by in situ TUNEL technique. Markers of the mitochondrial-mediated apoptotic pathway (cytochrome c release, caspase-9 activity, and BAX and BCL-2 levels), endoplasmic reticulum stress apoptotic pathway (caspase-12 activity and CHOP level), and death receptor apoptotic pathway (caspase-8 activity, and Fas and FasL levels) were also measured.</p><p><b>RESULT</b>FXR expression (3.7-fold higher, P < 0.01), myocardial infarct size [(62.1 ± 7.0)% vs. (33.8 ± 5.8)%, P < 0.01] and myocardial apoptosis index[ (36.8 ± 5.7)% vs. (17.2 ± 3.8)%, P < 0.01]were all significantly higher in high-fat ApoE(-/-) group than those in standard ApoE(-/-) group. Compared with high-fat ApoE(-/-) group, myocardial infarct size [(24.4 ± 4.7)% vs. (62.1 ± 7.0)%, P < 0.01] and myocardial apoptosis index [(13.8 ± 2.7)% vs. (36.8 ± 5.7)%, P < 0.01] were significantly reduced in high-fat ApoE(-/-) + FXR antagonist group. Moreover, levels of mitochondrial-mediated apoptotic pathway markers (cytochrome c release, caspase-9 activity, and BAX/BCL-2 levels) and endoplasmic reticulum stress apoptotic pathway markers (caspase-12 activity and CHOP level) were significantly lower in high-fat ApoE(-/-) + FXR antagonist group than those in high-fat ApoE(-/-) group (all P < 0.01). Levels of death receptor apoptotic pathway markers (caspase-8 activity, and Fas and FasL levels) were similar between high-fat ApoE(-/-) group and high-fat ApoE(-/-) + FXR antagonist group.</p><p><b>CONCLUSION</b>FXR antagonist alleviates myocardial reperfusion injury in cholesterol-fed ApoE(-/-) mice via inhibition of the mitochondrial-mediated and endoplasmic-reticulum stress pathway.</p>
Subject(s)
Animals , Male , Mice , Apolipoproteins E , Genetics , Apoptosis , Caspase 9 , Metabolism , Cholesterol, Dietary , Cytochromes c , Metabolism , Disease Models, Animal , Endoplasmic Reticulum Stress , Mice, Knockout , Myocardial Reperfusion Injury , Metabolism , Pathology , Pregnenediones , Pharmacology , Proto-Oncogene Proteins c-bcl-2 , Metabolism , Receptors, Cytoplasmic and Nuclear , Metabolism , bcl-2-Associated X Protein , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To establish a RP-HPLC method for determination of plasma progesterone and to apply the method for pharmacokinetics study of progesterone-loaded lipid nanoparticles after oral administration in rats.</p><p><b>METHODS</b>The plasma samples were collected from castrated rat after oral administration of progesterone-loaded lipid nanoparticles and extracted by acetic ether. The determination was performed on a Hypersil C18 column (150 mm X 3.9 mm , 5 microm) with a mobile phase consisting of methanol and water (60:40) at a flow-rate of 0.6 ml/min. The UV detector was at 240 nm and danazol was used as internal standard.</p><p><b>RESULT</b>Good linearity was obtained over the range of 0.02-2 microg/ml progesterone in plasma(r=0.9999, n=3). The quantification limit was (0.02 +/-0.004) microg/ml(n=3) and the limit of detection was 0.005 microg.mL(-1)(S/N = or >3). The inter-and intra-day RSDs were all less than 10% for quality control samples at high-, medium- and low-concentrations. The average absolute recovery rate was 90.5 % and the average method recovery was in the range of 93.4 %-107.5%. The plasma concentration-time curves indicated that tmax was delayed after administration of progesterone-loaded lipid nanoparticles, and the bioavailability was increased significantly, compared with contrast solution.</p><p><b>CONCLUSION</b>The method developed is stable, simple, rapid, accurate, sensitive and applicable for determining plasma concentrations of progesterone of progesterone-loaded lipid nanoparticles in pharmacokinetic studies.</p>
Subject(s)
Animals , Male , Rats , Administration, Oral , Chromatography, High Pressure Liquid , Methods , Drug Compounding , Lipids , Chemistry , Nanoparticles , Progesterone , Blood , Pharmacokinetics , Rats, Sprague-DawleyABSTRACT
<p><b>OBJECTIVE</b>To prepare the low molecular weight chitosan (LMWC) and establish the method for quality control.</p><p><b>METHOD</b>Use enzymatic degradation to prepare LMWC with chitosan, and separate by ultrafiltration; the molecular weight and purity were determined by gel permeation chromatography (GPC) and colorimetry respectively.</p><p><b>RESULT</b>LMWC was prepared by control the hours of enzymatic degradation and ultrafiltered through filter with cutoff molecular of 10K Dalton and 50 K dalton; the average molecular weight was 20 K dalton and the purity was (96.60 +/- 1.56)%.</p><p><b>CONCLUSION</b>The condition of enzymatic degradation is geniality and easy to control, LMWCs with different molecular weight can separate by ultrafiltration efficiently; the quality of LMWC can control with gel permeation chromatography (GPC) and colorimetry.</p>