Sodium Cholate Bile Acid-Stabilized Ferumoxytol-Doxorubicin-Lipiodol Emulsion for Transcatheter Arterial Chemoembolization of Hepatocellular Carcinoma.

PURPOSE: To develop bile acid-stabilized multimodal magnetic resonance (MR) imaging and computed tomography (CT)-visible doxorubicin eluting lipiodol emulsion for transarterial chemoembolization of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Ferumoxytol, a US Food and Drug Administration-approved iron oxide nanoparticle visible under MR imaging was electrostatically complexed with doxorubicin (DOX). An amphiphilic bile acid, sodium cholate (SC), was used to form a stable dispersion of ferumoxytol-DOX complex in lipiodol emulsion. Properties of the fabricated emulsion were characterized in various component ratios. Release kinetics of DOX were evaluated for the chemoembolization applications. Finally, in vivo multimodal MR imaging/CT imaging properties and potential therapeutic effects upon intra-arterial (IA) infusion bile acid-stabilized ferumoxytol-DOX-lipiodol emulsion were evaluated in orthotopic McA-Rh7777 HCC rat models. RESULTS: DOX complexed with ferumoxytol through electrostatic interaction. Amphiphilic SC bile acid at the interface between the aqueous ferumoxytol-DOX complexes and lipiodol enabled a sustained DOX release (17.2 ± 1.6% at 24 hours) at an optimized component ratio. In McA Rh7777 rat HCC model, IA-infused emulsion showed a significant contrast around tumor in both T2-weighted MR imaging and CT images (P = .044). Hematoxylin and eosin and Prussian blue staining confirmed the local deposition of IA-infused SC bile acid-stabilized emulsion in the tumor. The deposited emulsion induced significant increases in TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) stain-positive cancer cell apoptosis compared to those in a group treated with the nonstabilized emulsion. CONCLUSIONS: SC bile acid-stabilized ferumoxytol-DOX-lipiodol emulsion demonstrated sustained drug release and multimodal MR imaging/CT imaging capabilities. The new lipiodol-based formulation may enhance the therapeutic efficacy of chemoembolization in HCC.

Fiber and phenolic compounds contribution to the hepatoprotective effects of mango diets in rats fed high cholesterol/sodium cholate.

The present study evaluated the contribution of mango fiber (MF) and mango phenolic compounds (MP) to the hepatoprotective effect of freeze-dried mango pulp (FDM) cultivar (cv.) "Ataulfo" diets in high cholesterol/sodium cholate (HCC)-fed rats. Male Wistar rats were fed with a HCC diet for 12 weeks, either untreated, or supplemented with MF, MP, FDM, or a control diet (no HCC; n = 6/group). All mango treatments significantly decreased hepatic cholesterol deposition and altered its fatty acid profile, whereas MF and MP mitigated adipose tissue hypertrophy. MF caused a lower level of proinflammatory cytokines (IL-1α/ß, IFN-γ, TNF-α) whereas FDM increased the anti-inflammatory ones (IL-4, 6, 10). Mango treatments increased catalase (CAT) activity and its mRNA expression; superoxide dismutase (SOD) activity was normalized by MF and FDM, but its activity was unrelated to its hepatic mRNA expression. Changes in CAT and SOD mRNA expression were unrelated to altered Nrf2 mRNA expression. Higher hepatic PPARα and LXRα mRNA levels were found in MP and MF. We concluded that MF and MP are highly bioactive, according to the documented hepatoprotection in HCC-fed rats; their mechanism of action appears to be related to modulating cholesterol and fatty acid metabolism as well as to stimulating the endogenous antioxidant system.

Safety and efficacy of a novel plastic stent coated with stone-dissolving agents for the treatment of biliary stones in a porcine model.

BACKGROUND AND STUDY AIM: We previously reported on a plastic stent that was coated with ethylenediaminetetraacetic acid (EDTA) and sodium cholate, which dissolved common bile duct (CBD) stones ex vivo. The aim of this study was to investigate the safety and efficacy of such stents on biliary stones in a live porcine model. METHODS: Stents without coating or with degradable membranes containing 0 % or 50 % EDTA and sodium cholate were inserted together with human CBD stones into the porcine CBD. Serum laboratory variables, histological examinations of the bile duct, and the weight change in stones were compared during and after stent placement for 6 months. RESULTS: A total of 16 pigs were included (5 no coating, 5 0 % coating, 6 50 % coating). Biliary stones showed decreased weight in all groups; however, stones in the group with 50 % coated stents showed a greater reduction in weight compared with the no coating and the 0 % coating groups (269 ±â€Š66 mg vs. 179 ±â€Š51 mg [P = 0.09]; 269 ±â€Š66 mg vs. 156 ±â€Š26 mg [P = 0.01], respectively). CONCLUSIONS: The plastic stent coated with 50 % agent enhanced CBD stone dissolution in vivo and may be a promising tool for patients with difficult biliary stones.

Bile salts enhance the intestinal absorption of lipophilic drug loaded lipid nanocarriers: mechanism and effect in rats.

The purpose of this study was to elucidate the effect and possible mechanism of bile salts on the intestinal absorption of lipophilic drug loaded lipid nanocarriers in rats. Effects of sodium cholate (SC) on the characteristics, intestinal absorption, cellular uptake in Caco-2 cell monolayers and intestinal lymphatic transport of candesartan cilexetil loaded lipid nanocarriers (CLN) were investigated to clarify the possible mechanism. The intestinal absorption of candesartan from CLN was evidently improved over 16-fold compared with free drug suspension, and further significantly enhanced 1.79-fold after the addition of SC. The cellular uptake of CLN in Caco-2 cell monolayers at 37̊C and its colocalization with endoplasmic reticulum were obviously increased in the presence of SC. Moreover, the intestinal lymphatic transport of CLN was obviously enhanced by SC. These results implicated that bile salts could improve the cellular uptake of CLN in Caco-2 cell monolayers via the active processes and promote the intestinal absorption of CLN through the intestinal lymphatic pathway. Therefore, bile salts could be an important physiological factor affecting the intestinal absorption of lipophilic drugs loaded lipid nanocarriers.

[Experimental studies of therapeutic effect of Rheum officinale on acute pancreatitis].

OBJECTIVE: To investigate the therapeutic effect of Rheum officinale on acute pancreatitis. METHODS: Buffered sodium taurocholate (3% m/V) was injected into the pancreatico-biliary duct to induce acute pancreatitis. Death rate,coefficient of pancreas, serum amylyse (AMY), hemocuprein (SOD), TNF-alpha and IL-1beta level were examined at 6, 12 and 24 hours after operations. Pathology analysis were also obtained. RESULTS: Compared with corresponding pancreatitis groups,death rate, coefficient of pancreas, serum TNF-alpha and IL-1beta level of drug groups decreased remarkably (P < 0.05), while serum SOD level significantly increased (P < 0.01). Serum AMY level of drug groups increased at 6 h (P < 0.01), decreased at 12 h (P < 0.01) and had no statistics disparity at 24 h (P > 0.05) compared with respective pancreatitis group. Although score points of all drug groups were lower than corresponding pancreatitis groups, the growth tendency of both were similar. CONCLUSION: Rheum officinale Baill has the effect of prevention to pancreas pathological changes in the animal pattern, but not able to reverse the tendency.

Effects of rice proteins from two cultivars, Koshihikari and Shunyo, on hepatic cholesterol secretion by isolated perfused livers of rats fed cholesterol-enriched diets.

BACKGROUND/AIMS: The aim of the present study was to clarify the effect of rice proteins, with different contents of glutelin and prolamin, on the regulation of hepatic cholesterol output pathways and the development of hypocholesterolemia in rats. METHODS: Seven-week-old male Wistar rats were fed 2 types of rice protein from either the cultivar Koshihikari (RRP) or the cultivar Shunyo (SRP), or casein as a control, for 2 weeks (n = 6 for each group). Each diet was supplemented with 1% cholesterol and 0.25% sodium cholate. Using an isolated perfused liver, hepatic secretion of cholesterol into bile and the circulation was measured during a 4-hour perfusion. RESULTS: Total hepatic cholesterol secretions into the circulation were significantly reduced by both rice proteins (p < 0.05), and hepatic cholesterol secretions into very-low-density lipoproteins were also effectively decreased by RRP and SRP. In contrast, bile flow and biliary output of bile acids were significantly stimulated by RRP and SRP (p < 0.05). CONCLUSIONS: These results demonstrate that the key metabolic pathways of hepatic cholesterol are modified by both rice proteins leading to similar hypocholesterolemic effects. The increased excretion of biliary bile acids associated with a decreased output of hepatic cholesterol into the circulation suggests a functional reciprocal interrelationship between both of the hepatic cholesterol secretory pathways in the rice-protein-fed rats, regardless of rice protein type.

Effects of various dietary arginine and lysine concentrations on plasma and liver cholesterol concentrations in rats.

BACKGROUND: It has been hypothesized that the arginine:lysine ratio of dietary proteins influences cholesterol concentrations in plasma and liver of men and animals. This study was performed to test this hypothesis in rats by using diets with various concentrations of arginine and lysine, differing in their arginine:lysine ratios. METHODS: Two experiments with growing rats were performed, some of which received diets containing 4.5, 9 or 18 g arginine/kg and 9 or 18 g lysine/kg, respectively, for a period of 21 days. In the first experiment, a cholesterol-free diet was used; in the second experiment, a diet supplemented with cholesterol and sodium cholate as hypercholesterolaemic compounds was used. RESULTS: In experiment 1, increasing the arginine concentration lowered HDL and plasma cholesterol concentration; however, cholesterol concentrations in liver, LDL and VLDL remained unchanged. In experiment 2, increasing the arginine concentration lowered HDL cholesterol and increased liver cholesterol (p<0.05); cholesterol concentrations in plasma, LDL and VLDL remained unchanged. The only effect of the dietary lysine concentration concerned the effect on VLDL and liver cholesterol concentration, which were both lower in rats fed the diets with 18 g lysine/kg than in those fed the diets with 9 g lysine/kg (p<0.05). Varying the dietary arginine:lysine ratio between 0.25 and 2.0 had no influence on cholesterol concentration in LDL and VLDL in both experiments; HDL cholesterol concentration was lowered by increasing this ratio (p<0.05). CONCLUSION: The present study does not support the hypothesis that an increase in the dietary arginine:lysine ratio causes hypocholesterolaemic effects in rats.

Transepithelial electrical resistance is not a reliable measurement of the Caco-2 monolayer integrity in Transwell.

The significance of monitoring transepithelial electrical resistance (TEER) value during the study on drug absorption through Caco-2 monolayers in Transwells was re-evaluated. TEER value was monitored before, during, and after the absorption of Streptokinase (45 KD). Four enhancers--disodium ethylenediaminetetracetate (disodium EDTA), sodium cholate (NaC), sodium taurocholate (NaTC), and sodium caprate along with alpha-hemolysin (a cell membrane pore-forming toxin)--were used to signify the outcome of this study. Modified trypan blue exclusion technique was used to examine the Caco-2 cell viability throughout the absorption studies. The enhancers at the used concentration exhibited toxic effect on the Caco-2 cells as evident from the trypan blue exclusion studies. This toxic effect was not reflected by the TEER profile because TEER value dropped after the addition of the absorption enhancers. But it came back to its initial value after the cell culture media was replaced by enhancer-free media. This toxic effect was confirmed by the antiproliferation studies on the four enhancers and alpha-hemolysin against Caco-2 cells. Therefore, we concluded that the measurement of TEER is not a reliable method to determine the absorption enhancers toxicity or integrity of the Caco-2 monolayers in the Transwells.

The effect of taurine on the cholesterol metabolism in rats fed diets supplemented with cholestyramine or high amounts of bile acid.

The effects of taurine on serum cholesterol levels and hepatic cholesterol 7alpha-hydroxylase activity (CYP7A1) were studied in rats fed cholestyramine or high amounts of sodium cholate in order to alter the intestinal pool of bile acids. Rats were fed a diet supplemented with 1% cholesterol and 0.25% sodium cholate (high cholesterol, control; C), and C supplemented with 4% cholestyramine (CH) or 0.75% sodium cholate (BA) for 14 d. Taurine groups were fed the diet supplemented with 3% taurine (CT, CHT and BAT). Compared to rats fed C and BA diets, serum cholesterol levels were significantly reduced in rats fed CT and BAT diets, but a significant reduction of serum cholesterol by taurine feeding was not observed in the CHT group as compared to the CH group. An increase in hepatic CYP7A1 activity due to taurine intake was observed in the CT and BAT groups. However, the simultaneous administration of cholestyramine and taurine (CHT group) did not increase hepatic CYP7A1 activity compared the intake of cholestyramine only (CH group). A significant increase in fecal bile acid excretion due to taurine intake was found only in rats fed the CT diet. In conclusion, it is suggested that taurine facilitates hepatic CYP7A1 activity regardless of the enlarged intestinal pool of bile acids due to increased intake of exogenous bile acid, and then reduces the serum cholesterol concentration.