Comparison of intravascular ultrasound-guided with angiography-guided double kissing crush stenting for patients with complex coronary bifurcation lesions: Rationale and design of a prospective, randomized, and multicenter DKCRUSH VIII trial.

BACKGROUND: Double kissing (DK) crush approach for patients with coronary bifurcation lesions, particularly localized at distal left main or lesions with increased complexity, is associated with significant reduction in clinical events when compared with provisional stenting. Recently, randomized clinical trial has demonstrated the net clinical benefits by intravascular ultrasound (IVUS)-guided implantation of drug-eluting stent in all-comers. However, the improvement in clinical outcome after DK crush treatment guided by IVUS over angiography guidance for patients with complex bifurcation lesions have never been studied in a randomized fashion. TRIAL DESIGN: DKCRUSH VIII study is a prospective, multicenter, randomized controlled trial designed to assess superiority of IVUS-guided vs angiography-guided DK crush stenting in patients with complex bifurcation lesions according to DEFINITION criteria. A total of 556 patients with complex bifurcation lesions will be randomly (1:1 of ratio) assigned to IVUS-guided or angiography-guided DK crush stenting group. The primary end point is the rate of 12-month target vessel failure, including cardiac death, target vessel myocardial infarction, or clinically driven target vessel revascularization. The secondary end points consist of the individual component of primary end point, all-cause death, myocardial infarction, and in-stent restenosis. The safety end point is the incidence of definite or probable stent thrombosis. An angiographic follow-up will be performed for all patients at 13 months and clinical follow-up will be continued annually until 3 years after the index procedure. CONCLUSIONS: DKCRUSH VIII trial is the first study designed to evaluate the differences in efficacy and safety between IVUS-guided and angiography-guided DK crush stenting in patients with complex true bifurcation lesions. This study will also provide IVUS-derived criteria to define optimal DK crush stenting for bifurcation lesions at higher complexity.

Newly identified peptide hormone inhibits intestinal fat absorption and improves NAFLD through its receptor GPRC6A.

BACKGROUND & AIMS: Circulating peptides and G protein-coupled receptors (GPCRs) have gained much attention because of their biofunctions in metabolic disorders including obesity and non-alcoholic fatty liver disease (NAFLD). Herein, we aimed to characterize the role and therapeutic potential of a newly identified peptide hormone in NAFLD. METHODS: Using bioinformatics, we identified a murine circulating pentadecapeptide flanked by potential convertase cleavage sites of osteocalcin (OCN), which we named 'metabolitin (MTL)'. We used ligand-receptor binding, receptor internalization, bioluminescence resonance energy transfer and Nano isothermal titration calorimetry assays to study the binding relationship between MTL and GPRC6A. For in vivo biological studies, wild-type mice kept on a high-fat diet (HFD) were injected or gavaged with MTL to study its function in NAFLD. RESULTS: We confirmed that MTL binds to GPRC6A and OCN interacts with GPRC6A using in vitro biological studies. Both intraperitoneal and oral administration of MTL greatly improved NAFLD and insulin resistance in a mouse model. Interacting with GPRC6A expressed in intestines, MTL can significantly inhibit intestinal neurotensin secretion, which in turn inhibits triglyceride but not cholesterol gut absorption, mediated by the 5'AMP-activated protein kinase pathway. In addition, glucagon like peptide-1 secretion was induced by MTL treatment. CONCLUSIONS: Oral or intraperitoneal MTL significantly improves the symptoms of NAFLD by inhibiting lipid absorption and insulin resistance. MTL could be a potential therapeutic candidate for the treatment of NAFLD. LAY SUMMARY: A novel murine peptide hormone, herein named 'metabolitin', inhibits fatty acid absorption and improves systemic insulin resistance in a murine model of obesity and non-alcoholic fatty liver disease. Thus, metabolitin has therapeutic potential for the treatment of patients with non-alcoholic fatty liver disease.

[Effects of Rapamycin and Rapamycin-loaded Poly(lactic-co-glycolic)Acid Nanoparticles on Apoptosis and Expression of bcl-2 and p27(kip1) Proteins of Human Umbilical Arterial Vascular Smooth Muscle Cell].

OBJECTIVE: To investgate the effects of rapamycin(RPM)and RPM-loaded poly(lactic-co-glycolic)acid(PLGA)nanoparticles(NPs)on the apoptosis of human umbilical arterial vascular smooth muscle cells(HUASMCs)in vitro and expression of bcl-2 and p27(kip1) protein. METHODS: HUASMCs were cultured in vitro and divided to RPM and RPM-PLGA-NPs groups treated at 3 different concentration by 12 and 24 hours,with M231-smooth muscle growth supplements medium and null-PLGA-NPs treated groups as controlled. The apoptosis of HUASMCs was determined by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling staining and flow cytometry. The expressions of bcl-2 and p27(kip1) were detected by streptacidin/peroxidase immunohistochemical method. The effect on cellular proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromidecolorimetry. RESULTS: The proliferation of HUASMCs was inhibited by RPM and RPM-PLGA-NPs in a dose-dependent manner. DNA electrophoresis showed DNA ladder in RPM and RPM-PLGA-NPs groups and classical scalar strips in control groups. The apoptotic indexes of RPM 100 ng/ml group and RPM-PLGA-NPs 500 ng/ml group detected by flow cytometry were(45.45<2.36)% and(35.04<5.64)%,respectively,which were significantly higher than that of M231-smooth muscle growth supplements control group [(2.60<0.95)%,all P<0.01]. The apoptotic indexes of groups incubated with RPM and RPM-PLGA-NPs for 24 hours were significantly higher than those of groups which incubated for 12 hours(P<0.05,P<0.01). The positive expression indexes(PEI)of p27(kip1) and bcl-2 protein were higher in RPM and RPM-PLGA-NPs groups than that of control groups. The Spearman's rank correlation coefficient test showed that there was no significant correlation between the PEI of p27(kip1) and the apoptotic indexes in the RPM group and RPM-PLGA-NPs group(P>0.05). CONCLUSIONS: Rapamycin-loaded PLGA nanoparticles and rapamycin have similar effects in inhibiting proliferation and inducing apoptosis;meanwhile,they upregulate the expression of p27(kip1) protein without downregulating the expression of bcl-2 protein in HUASMCs in vitro. RPM-PLGA-NPs has more potent pro-apoptotic effect than equivalent dose of RPM but is not linearly correlated with the p27(kip1) expression level.

[Effects of rapamycin-loaded poly(lactic-co-glycolic) acid nanoparticles on distribution of cell cycle, expression of p27 protein, and proliferation of human umbilical arterial vascular smooth muscle cell in vitro].

OBJECTIVE: To evaluate the effects of rapamycin (RPM)-loaded poly (lactic-co- glycolic) acid (PLGA) nanoparticles (NPs) on the proliferation, distribution of cell cycle, and expression of p27 protein in human umbilical arterial vascular smooth muscle cell (HUASMC) in vitro. METHODS: The primarily culture model of HUASMC was successfully established by explant-attached method in vitro. The cells were administrated with different doses of RPM, and RPM-PLGA NPs were observed as treat groups compared with PLGA NPs and M231-SMGs medium cultured group. The effect of RPM-PLGA NPs on proliferation of HUASMC was assessed using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) colorimetry method. The influences of RPM-PLGA NPs on the cell cycle and cellular growth kinetics of HUASMCs were tested by flow cytometry. The effect of RPM-PLGA NPs on the expression of p27 protein of HUASMCs was assessed through an immunohistochemical method. RESULTS: Compared with the control group, the proliferation of HUASMCs was inhibited by 50 microg/L and higher concentration of RPM-PLGA NPs in a dose-dependent manner (P < 0.05). The numbers of cells entering cell cycle of S/G2/M phases were significantly lower in RPM-PLGA NPs and RPM treated groups. Histologically, the expression of p27 were up-regulated in 500 microg/L RPM-PLGA NPs and 100 microg/L RPM treated group (all P < 0.01 ) when compared with the control group. CONCLUSIONS: RPM-PLGA NPs has a similar effects as RPM in inhibiting the growth of in vitro cultured HUASMC. It can remarkably suppress the expression of in vitro cultured HUASMC p27 protein, arrest its cell cycle at G1/S phase, and inhibit its proliferation.

[Rapamycin-loaded poly (lactic-co-glycolic) acid nanoparticles for intraarterial local drug delivery: preparation, characterization, and in vitro/in vivo release].

OBJECTIVE: To sought to engineer and characterize a biodegradable nanoparticles (NPs) containing rapamycin which use poly (lactic-co-glycolic) acid (PLGA) as the carrier matrix and to assess its in vivo release characteristics by local drug delivery system intravascularly. METHODS: Rapamycin-loaded PLGA NPs were prepared by an emulsification/solvent evaporation technique, and NPs size distribution was assessed by submicro laser defractometer. The particle morphology was observed by scanning electron microscopy. In vitro release from the NPs was performed in TE buffer at 37 degrees C under rotation utilizing double-chamber diffusion cells on a shake stander. In vivo NPs intravascular local delivery were performed by DISPATCH catheter in New Zealand rabbit abdominal aorta and Chinese experimental mini-pigs coronary artery models. RESULTS: Biodegradable rapamycin loaded PLGA NPs were constructed successfully by emulsification solvent-evaporation technique. The diameter of rapamycin-PLGA NPs was around 246.8 nm with very narrow size distribution, and rapamycin-NPs showed good spherical shape with smooth uniform surface. Rapamycin loaded in NPs were around was 19.42%. Encapsulation efficiency of drug was over 77.53%. The in vitro release of rapamycin from NPs showed that 75% of the drug was sustained released over 2 weeks and controlled release in a linear pattern. After a single 10 minutes infusion of rapamycin-PLGA NPs suspension (5 mg/ml) under 20.27 kPa through DISPATCH catherter in vivo, the mean rapamycin levels at 7 day and 14 day were (2.438 +/- 0.439) and (0.529 +/- 0.144) microg/mg of the dry-weight of the artery segments (2 cm) which local delivery were administrated. CONCLUSIONS: PLGA NPs controlled drug delivery system for intraarterial local anti-proliferative drug delivery can potentially improve local drug concentration and prolong drug residence time in animal model in vivo. It should be appropriate for further study of its therapy efficiency in human.

Effects of xuezhikang, an extract of cholestin, on lipid profile and C-reactive protein: a short-term time course study in patients with stable angina.

BACKGROUND: Reduction of cholesterol and inflammation can be achieved by administration of a statin. Xuezhikang, an extract of cholestin, available from Chinese red yeast rice, could effectively modify the lipid profile. However, limited information is available regarding rapid effects of Xuezhikang on plasma C-reactive protein (CRP) and the lipid profile in patients with stable angina. We evaluated the short-term time course effects of lipid profile and CRP by Xuezhikang in patients with stable angina. METHODS: Forty-eight consecutive patients with stable angina were randomly assigned to 1200 or 2400 mg/day of Xuezhikang. Blood samples were drawn at days 0, 1, 7 and 14 for lipid profile and CRP levels in all patients, and hepatic enzymes were also evaluated at days 0 and 14. RESULTS: Both doses of Xuezhikang induced significant reductions in median CRP levels and in mean CRP levels at day 1 (13.0% with 1200 and 16.6% with 2400 mg/day; 14.7% with 1200 and 18.4% with 2400 mg/day), and at day 7 (18.3% with 1200 and 20.2% with 2400 mg/day; 18.5% with 1200 and 22.6% with 2400 mg/day) as well as at day 14 (28.6% with 1200 and 30.4% with 2400 mg/day; 21.7% with 1200 and 24.8% with 2400 mg/day) compared with baseline without a dose-dependent effect but a time-dependent manner. In addition, no changes were found at days 1 and 7 regarding lipid profile. However, both doses of Xuezhikang induced significant reductions in total cholesterol (TC, 13% and 22%), and low-density lipoprotein (LDL) cholesterol (23% and 32%) compared with baseline at day 14. The higher dose of Xuezhikang (2400 mg/day) resulted in significantly greater reductions in TC and LDL cholesterol compared with 1200 mg/day group (p<0.05, p<0.01, respectively). A less significant reduction was observed in triglycerides (TG) level (13% and 23%) compared with TC and LDL cholesterol. There was no significant difference in mean high-density lipoprotein (HDL) cholesterol levels compared with baseline in both groups. CONCLUSIONS: Xuezhikang resulted in rapid reduction of CRP within 24 h and lipid profile within 2 weeks, which may be clinically important for patients with coronary artery disease.