Changes of lipid metabolism in plasma, liver and bile during cholesterol gallstone formation in rabbit model

Is Cholecystectomy in Patients with Symptomatic Uncomplicated Cholelithiasis Beneficial in Improving the Lipid Profile?

Introduction

Gallstone disease is an emerging health issue worldwide with its incidence on the rise. The development of gallstone disease is multifactorial, with risk factors including increased age, female sex, obesity, and the use of oral contraceptive pills. It has been established that more than 50% of patients with gallstone disease have a coexisting lipid disorder. Cholecystectomy, the definitive management of gallstones, may improve the lipid profiles of some patients.

Objectives

This study aims to examine the postoperative changes in the lipid profiles of patients who underwent cholecystectomy. These lipid profiles include levels of low-density lipoprotein (LDL), triglycerides (TG), high-density lipoprotein (HDL), total cholesterol (TC), and the Chol/HDL ratio.

Methods

This retrospective study included 55 patients who underwent cholecystectomy between 2013 and 2017. Biochemical parameters, which include LDL, TG, HDL, and TC levels, were collected using the hospital’s recording system, in addition to the calculation of the Chol/HDL ratio.

Results

Statistically significant changes included a reduction in the mean LDL values in the two-, four-, and six-month postoperative periods (P = 0.029, 0.000, and 0.008, respectively), increased mean TG levels one-week postoperatively (P = 0.034), decreased mean TC levels at four (P = 0.049) and six months (P = 0.026) after cholecystectomy, and increased Chol/HDL ratio at two and 12 months postoperatively (P = 0.03, and 0.022, respectively).

Conclusions

From the results, it can be concluded that cholelithiasis is associated with abnormal lipid profiles and that undergoing cholecystectomy may improve them and reduce the future risk of developing coronary artery disease. However, further research is needed to confirm this association.

Serum Lipid and Lipoproteins in Gallstone Patients

Serum lipid and lipoprotein concentrations were determined in a group of thirty two gallstone patients and compared to the values obtained in thirty two healthy control subjects. The serum levels of high density lipoprotein cholesterol and lipoprotein(a) in gallstone patients were found to be lower than that of the control group. Total cholesterol, triglyceride, low density lipoprotein cholesterol, apoprotein-A and apoprotein-B concentrations were observed to be higher in gallstone patients than the controls. The differences in triglyceride and low density lipoprotein cholesterol concentration were statistically significant. However, there was no significant difference in high density lipoprotein cholesterol, lipoprotein( a), apoprotein-A, apoprotein-B, and total cholesterol concentrations between groups. It is concluded that gallstone formation may be related to a disturbance in lipid and lipoprotein metabolism.

In vivo biochemical and gene expression analyses of the antioxidant activities and hypocholesterolaemic properties of Tamarindus indica fruit pulp extract

BACKGROUND

Tamarindus indica (T. indica) is a medicinal plant with many biological activities including anti-diabetic, hypolipidaemic and anti-bacterial activities. A recent study demonstrated the hypolipidaemic effect of T. indica fruit pulp in hamsters. However, the biochemical and molecular mechanisms responsible for these effects have not been fully elucidated. Hence, the aims of this study were to evaluate the antioxidant activities and potential hypocholesterolaemic properties of T. indica, using in vitro and in vivo approaches.

METHODOLOGY/PRINCIPAL FINDINGS

The in vitro study demonstrated that T. indica fruit pulp had significant amount of phenolic (244.9 ± 10.1 mg GAE/extract) and flavonoid (93.9 ± 2.6 mg RE/g extract) content and possessed antioxidant activities. In the in vivo study, hamsters fed with high-cholesterol diet for ten weeks showed elevated serum triglyceride, total cholesterol, HDL-C and LDL-C levels. Administration of T. indica fruit pulp to hypercholesterolaemic hamsters significantly lowered serum triglyceride, total cholesterol and LDL-C levels but had no effect on the HDL-C level. The lipid-lowering effect was accompanied with significant increase in the expression of Apo A1, Abcg5 and LDL receptor genes and significant decrease in the expression of HMG-CoA reductase and Mtp genes. Administration of T. indica fruit pulp to hypercholesterolaemic hamsters also protected against oxidative damage by increasing hepatic antioxidant enzymes, antioxidant activities and preventing hepatic lipid peroxidation.

CONCLUSION/SIGNIFICANCE

It is postulated that tamarind fruit pulp exerts its hypocholesterolaemic effect by increasing cholesterol efflux, enhancing LDL-C uptake and clearance, suppressing triglyceride accumulation and inhibiting cholesterol biosynthesis. T. indica fruit pulp has potential antioxidative effects and is potentially protective against diet-induced hypercholesterolaemia.

Roles of ApoB-100 gene polymorphisms and the risks of gallstones and gallbladder cancer: a meta-analysis

Background

Gallstones (GS) is the major manifestation of gallbladder disease, and is the most common risk factor for gallbladder cancer (GBC). Previous studies investigating the association between ApoB-100 gene polymorphisms and the risks of GS and GBC have yielded conflicting results. Therefore, we performed a meta-analysis to clarify the effects of ApoB-100 gene polymorphisms on the risks of GS and GBC.

Methods

A computerized literature search was conducted to identify the relevant studies from PubMed and Embase. Fixed or random effects model was selected based on heterogeneity test. Publication bias was estimated using Begg’s funnel plots and Egger’s regression test.

Results

A total of 10, 3, and 3 studies were included in the analyses of the association between ApoB-100 XbaI, EcoRI, or insertion/deletion (ID) polymorphisms and the GS risks, respectively, while 3 studies were included in the analysis for the association between XbaI polymorphism and GBC risk. The combined results showed a significant association in Chinese (X+ vs. X−, OR = 2.37, 95%CI 1.52–3.70; X+X+/X+X- vs. X+X+, OR = 2.47, 95%CI 1.55–3.92), but not in Indians or Caucasians. Null association was observed between EcoRI or ID polymorphisms and GS risks. With regard to the association between XbaI polymorphism and GBC risk, a significant association was detected when GBC patients were compared with healthy persons and when GBC patients were compared with GS patients. A significant association was still detected when GBC patients (with GS) were compared with the GS patients (X+X+ vs. X-X−, OR = 0.33, 95%CI 0.12–0.90).

Conclusion

The results of this meta-analysis suggest that the ApoB-100 X+ allele might be associated with increased risk of GS in Chinese but not in other populations, while the ApoB-100 X+X+ genotype might be associated with reduced risk of GBC. Further studies with larger sample sizes are needed to confirm these results.

Soy protein, genistein, and daidzein improve serum paraoxonase activity and lipid profiles in rheumatoid arthritis in rats

In this study, we investigated the effects of genistein, daidzein, and soy protein on paraoxonase and arylesterase activity, malondialdehyde (MDA) levels, and lipid profiles of arthritic rats in vivo and the results were compared with that of dexamethasone. Seventy-two female Sprague-Dawley rats were divided into six groups: healthy control, animals with collagen-induced arthritis (CIA), CIA-soy protein (7 g/kg)-treated rats, CIA-genistein (20 mg/kg)-treated animals, CIA-daidzein (20 mg/kg)-treated rats, and CIA-dexamethasone (1 mg/kg)-treated rats. Rheumatoid arthritis was induced using collagen type II and the treatments were carried out by daily gavages feedings for 50 days. The paraoxonase activity in serum was measured spectrophotometrically using paraoxon and phenylacetate as substrates. Serum MDA and lipids levels were determined using enzymatic colorimetric methods. Arthritis-induced decreases in paraoxonase and arylesterase activity was restored after treatment with soy protein and isoflavones (P<.05). MDA concentrations were lower after treatment with all tested compounds. However, only soy protein could partially improve the lipid profile.

Ursodeoxycholic acid lowers bile lithogenicity by regulating SCP2 expression in rabbit cholesterol gallstone models

Aims: We designed this study to get insight into the disorder of lipid metabolism during cholesterol gallstone formation and evaluate the effect of ursodeoxycholic acid on the improvement of bile lithogenicity and on expression of lipid related genes.

Methods: Rabbit cholesterol gallstone models were induced by high cholesterol diet. Bile, blood and liver tissues were obtained from rabbits after 0, 1, 2, 3, 4 and 5 weeks. Bile and blood lipids were measured enzymatically. 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), cytochrome P450, family 7, subfamily A, polypeptide 1 (CYP7A1) and sterol carrier protein 2 (SCP2) mRNA expressions were detected by using quantitative real-time RT-PCR. Cholesterol saturation index (CSI) was calculated by using Carey table to represent the bile lithogenicity.

Results: Rates of gallstone formation of the 4 and 5 week treatment groups were 100 %, but that of the ursodeoxycholic acid treatment group was only 33.3 %. Expression of HMGCR and SCP2 mRNA in the 4 week group was upregulated and that of CYP7A1 mRNA decreased as compared with the 0 week group. Ursodeoxycholic acid could significantly extend nucleation time of bile and lower CSI. Ursodeoxycholic acid could reduce the expression of SCP2, but couldn't influence expression of HMGCR and CYP7A1.

Conclusions: Abnormal expression of HMGCR, CYP7A1 and SCP2 might lead to high lithogenicity of bile. Ursodeoxycholic acid could improve bile lipids and lower bile lithogenicity, thereby reducing the incidence of gallstones. So it might be a good preventive drug for cholesterol gallstones.

A large, consistent plasma proteomics data set from prospectively collected breast cancer patient and healthy volunteer samples

Background

Variability of plasma sample collection and of proteomics technology platforms has been detrimental to generation of large proteomic profile datasets from human biospecimens.

Methods

We carried out a clinical trial-like protocol to standardize collection of plasma from 204 healthy and 216 breast cancer patient volunteers. The breast cancer patients provided follow up samples at 3 month intervals. We generated proteomics profiles from these samples with a stable and reproducible platform for differential proteomics that employs a highly consistent nanofabricated ChipCube™ chromatography system for peptide detection and quantification with fast, single dimension mass spectrometry (LC-MS). Protein identification is achieved with subsequent LC-MS/MS analysis employing the same ChipCube™ chromatography system.

Results

With this consistent platform, over 800 LC-MS plasma proteomic profiles from prospectively collected samples of 420 individuals were obtained. Using a web-based data analysis pipeline for LC-MS profiling data, analyses of all peptide peaks from these plasma LC-MS profiles reveals an average coefficient of variability of less than 15%. Protein identification of peptide peaks of interest has been achieved with subsequent LC-MS/MS analyses and by referring to a spectral library created from about 150 discrete LC-MS/MS runs. Verification of peptide quantity and identity is demonstrated with several Multiple Reaction Monitoring analyses. These plasma proteomic profiles are publicly available through ProteomeCommons.

Conclusion

From a large prospective cohort of healthy and breast cancer patient volunteers and using a nano-fabricated chromatography system, a consistent LC-MS proteomics dataset has been generated that includes more than 800 discrete human plasma profiles. This large proteomics dataset provides an important resource in support of breast cancer biomarker discovery and validation efforts.

The mechanism of dietary cholesterol effects on lipids metabolism in rats

Background

Cholesterol administration has been reported to influence hepatic lipid metabolism in rats. In the present study, the effect of dietary cholesterol on hepatic activity and mRNA expression of the enzymes involved in lipid metabolism were investigated. Fourteen male Wistar rats were randomly divided into 2 groups and fed 1% cholesterol or cholesterol free AIN76 diets for 4 weeks.

Results

The serum triglyceride and high density lipoprotein cholesterol levels were significantly decreased but the total cholesterol and non high density lipoprotein cholesterol levels were significantly increased in the cholesterol-fed rats compared with the control rats. And the concentrations of the hepatic total cholesterol and triglyceride increased about 4-fold and 20-fold separately by dietary cholesterol. The activities of hepatic malic enzyme, glucose-6-phosphate dehydrogenase, fatty acid synthase, phosphatidate phophatase and carnitine palmitoyl transferase were depressed by the cholesterol feeding (40%, 70%, 50%, 15% and 25% respectively). The results of mRNA expression showed that fatty acid synthase, carnitine palmitoyl transferase 1, carnitine palmitoyl transferase 2, and HMG-CoA reductase were down-regulated (35%, 30%, 50% and 25% respectively) and acyl-CoA: cholesterol acyltransferase and cholesterol 7α-hydroxylase were up regulated (1.6 and 6.5 folds) in liver by the cholesterol administration.

Conclusions

The dietary cholesterol increased the triglyceride accumulation in liver, but did not stimulate the activity and the gene expression of hepatic enzymes related to triglyceride and fatty acid biosynthesis.

Effect of portal azygous disconnection on gallbladder motor function

AIM: To investigate and clarify the effect of vagus on gallbladder motility through a comparative study.

METHODS: Twenty-three hepatocirrhosis patients with portal hypertension were included in this study. In Hassab operation group, the anterior and posterior trunk of vagus were surgically excised (H, n = 18); In vena coronaria ventriculi embolization group, the vena coronaria ventriculi bole was ligated and injected TH adhesive (8 mL) after splenectomy (VCE, n = 5). Before operation and 10 d after operation, ^99mTc-labeled diethyl acetyl acid anilide iminodiacetic acid (^99mTc-EHIDA, 185 MBq) was administered intravenously to the patients, and then scintigraphic method was used to assess the motor function of gallbladder. The index including radiocounting 30 min after injected ^99mTc-EHIDA (GBRC 30min), emptying fraction (GBEF), emptying period (GBEP), emptying rate (GBER), latent period (GBLP), latent period radiocounting increment (GBLI) and latent period radiocounting increment rate (GBLR) were analyzed.

RESULTS: GBRC 30 min in H group was significantly lower after operation than that before operation (74.8 ± 66.9 vs 155.7 ± 72.9,P < 0.05); GBLP was very short in pre-operation, and GBLP prolonged significantly after operation (13.36 ± 5.92 vs 2.24 ± 1.48, P < 0.01); the gallbladder radiocounting increased gradually during GBLP; the GBLI and GBLP level were very low before operation, but the GBLI and GBLP increased significantly after operation (79.5 ± 56.3 vs 9.2 ± 11.7, 113.4 ± 49.5 vs 7.6 ± 10.8, P < 0.01); GBEP shortened significantly after operation (18.5 ± 6.3 vs 24.1 ± 6.4, P < 0.05); GBEF and GBER decreased obviously after operation (13.1 ± 5.4 vs 32.3 ± 16.3, 0.7 ± 0.3 vs 1.4 ± 0.8, P < 0.01). The preceding parameters in VCE group had no significant difference before and after operation (P > 0.05).

CONCLUSION: The gallbladder tension weakens obviously in interdigestive phase after the vagus is excised; the gallbladder contraction delays, and the motor function weakens obviously after meals.

Relationship between bilirubin free radical and formation of pigment gallstone

In this paper, we summarize the main progresses made in our group in the field of the mechanism of pigment gallstone formation. It was found that after treatment with free radicals, bilirubin (BR) was changed into free radical itself, and a semiquinone free radical and a superoxide free radical bound with metal were recognized, which was detected by ESR (electron spin resonance). By the means of NMR (nuclear magnetic resonance) and IR (Infra-red spectra), it was postulated that bilirubin polymerized through the reaction between the vinyl group and the hydroxyl group under the attack of free radicals. It was also found that bilirubin free radical were liable to calcify in a kinetic study. Because of its chemical properties, bilirubin free radical was shown to be cytotoxic to hepatocyte, which was demonstrated based on the following facts: induction of phospholipid peroxidation (LPO), leakage of lactate dehydrogenase (LDH) and decrease of glutathione. As to the mechanism of bilirubin-induced cytotoxicity, it was postulated that the main target of bilirubin free radical was the cell membrane, including phospholipid and membrane bound proteins, especially spectrin, a content of cytoskeleton. Based on the results mentioned above, it was deduced that bilirubin free radical is the key factor that initiates and promotes the formation of pigment gallstone, which is consistent with other researches in recent years.

Single and multiple cholesterol gallstones and the influence of bacteria

Single and multiple cholesterol gallstones constitute at least 80% of the gallstone population observed at cholecystectomy in Western countries. While supersaturation of bile with cholesterol is necessary for gallstone growth, the kinetic determinant of crystal nucleation is perhaps the critical factor leading to the incidence of gallstones. Nucleation involves aggregation of nidus-forming materials like pigment precipitates and mucus proteins. In combination with cholesterol precipitates and crystal formation, gallstone propagation is enhanced. Bacterial species may augment the process of nucleation and gallstone growth by contributing specific enzyme activities resulting in the formation of insoluble precipitates in bile, or by acting as a nidus upon which the deposition of cholesterol crystals may initiate gallstone formation. The utilization of Raman microscopic techniques permits detailed mapping of the distribution of the gallstone components leading to identification and characterization of the site of nucleation. This, when coupled to molecular genetic tools such as PCR DNA amplification, would permit elucidation of the role of bacteria in vivo gallstone propagation mechanisms.