Rifaximin Prevents Intestinal Barrier Dysfunction and Alleviates Liver Injury in MCT-induced HSOS Mice

OBJECTIVE

Rifaximin is an effective component of treatment strategies for liver and intestinal diseases. However, the efficacy of rifaximin in hepatic sinusoidal obstruction syndrome (HSOS) has not been explored. The present study aimed to investigate the efficacy and mechanism of rifaximin in HSOS.

METHODS

An HSOS model was established in mice through the administration of monocrotaline (MCT, 800 mg/kg), and part of the HSOS mice were intragastrically administered with rifaximin. Then, the efficacy of rifaximin in HSOS was evaluated based on the liver pathological findings, liver proinflammatory cytokines, and alanine aminotransferase and aspartate aminotransferase levels. The Ussing chamber was used to evaluate the intestinal permeability, and tight junction (TJ) proteins were measured by Western blotting and real-time polymerase chain reaction to evaluate the intestinal barrier integrity. Then, the serum proinflammatory cytokine levels were evaluated by enzyme-linked immunosorbent assay. Afterwards, an in vitro experiment was performed to determine the relationship between rifaximin and TJ proteins.

RESULTS

Rifaximin effectively alleviated the MCT-induced HSOS liver injury, suppressed the expression of liver proinflammatory cytokines, and reduced the serum levels of tumor necrosis factor-alpha and interleukin-6. Furthermore, rifaximin reduced the intestinal permeability, improved the intestinal barrier integrity, and promoted the expression of TJ proteins.

CONCLUSION

The results revealed that the intestinal barrier integrity was destroyed in MCT-induced HSOS. The significant alleviation of MCT-induced HSOS induced by rifaximin might be correlated to the repairment of intestinal barrier integrity via the regulation of the TJ protein expression.

Clinical treatment of chronic hepatitis B virus infection in indeterminate phase: Current status and future prospects

The natural history of chronic hepatitis B virus (HBV) infection is usually divided into four stages: Immune tolerant phase (IT), hepatitis B e antigen (HBeAg) positive chronic hepatitis B (CHB) (i.e., immune clearance phase), immune control (IC) phase, and HBeAg negative CHB (i.e., reactivation phase). Patients whose HBeAg, alanine aminotransferase (ALT), HBV DNA, and hepatic histopathology fall into an indeterminate phase are divided into the following four groups: (1) Indeterminate phase related to IT: HBV DNA < 10⁶ IU/mL or significant inflammation and fibrosis, while other indicators are in line with IT; (2) Indeterminate phase related to HBeAg positive CHB: HBV DNA < 2 × 10⁴ IU/mL or ALT 1-2 times the upper limit of normal (ULN), while the rest indicators are consistent with HBeAg positive CHB; (3) Indeterminate phase related to IC: HBV DNA > 2 × 10³ IU/mL or significant inflammation and fibrosis, while other indicators meet IC; and (4) Indeterminate phase related to HBeAg negative CHB: HBV DNA < 2 × 10³ IU/mL or ALT 1-2 ULN, while the remaining indicators are in accordance with HBeAg negative CHB. In China, it is estimated that about 70 million people have chronic HBV infection, of which about 20-30 million are CHB patients. The percentage of liver cirrhosis and hepatocellular carcinoma caused by HBV infection is 77% and 84%, respectively. Chronic HBV infection brings severe burden to people's life and health as well as the national health care system. Although existing guidelines recommend dynamic monitoring of serum ALT and HBV DNA levels and assessment of liver histology of indeterminate zone, whether to initiate antiviral therapy in these patients remains controversial. This review mainly introduces the clinical treatment status of CHB patients in IC and indeterminate phase related to IC, and the future prospects of antiviral treatment for these patients.

Mechanisms of ductular reaction in non-alcoholic steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is a disease spectrum caused in part by insulin resistance and genetic predisposition. This disease is primarily characterized by excessive lipid accumulation in hepatocytes in the absence of alcohol abuse and other causes of liver damage. Histologically, NAFLD is divided into several periods: simple steatosis, non-alcoholic steatohepatitis (NASH), hepatic fibrosis, cirrhosis, and hepatocellular carcinoma. With the increasing prevalence of obesity and hyperlipidemia, NAFLD has become the main cause of chronic liver disease worldwide. As a result, the pathogenesis of this disease is drawing increasing attention. Ductular reaction (DR) is a reactive bile duct hyperplasia caused by liver injury that involves hepatocytes, cholangiocytes, and hepatic progenitor cells. Recently, DR is shown to play a pivotal role in simple steatosis progression to NASH or liver fibrosis, providing new research and treatment options. This study reviews several DR signaling pathways, including Notch, Hippo/YAP-TAZ, Wnt/β-catenin, Hedgehog, HGF/c-Met, and TWEAK/Fn14, and their role in the occurrence and development of NASH.

Effectiveness of Tenofovir Alafenamide in Chronic Hepatitis B Patients with Normal Alanine Aminotransferase and Positive Hepatitis B Virus DNA

BACKGROUND AND AIMS

With an increasing understanding of hepatitis B, the antiviral indications have been broadening gradually. To evaluate the effectiveness of tenofovir alafenamide (TAF) in chronic hepatitis B (CHB) patients with normal alanine aminotransferase (ALT) and detectable hepatitis B virus (HBV) DNA, those who are ineligible for broader antiviral criteria from the Chinese CHB prevention guide (2019).

METHODS

A total of 117 patients were recruited and their data were collected from paper or electronic medical records. HBV DNA and liver function were measured at baseline and throughout the 24-week follow-up. The effectiveness endpoint was complete virological response. The safety endpoint was the first occurrence of any clinical adverse event during the treatment.

RESULTS

Among the 117 patients, 45 had normal ALT as well as detectable HBV DNA and they were not recommended for antiviral therapy according to Chinese Guidelines (2019). After TAF antiviral therapy, the rates of patients who achieved HBV DNA <20 IU/mL at 4, 12 and 24 weeks were 77.1%, 96.7% and 96.8% respectively. Among them, the undetectable rates of HBV DNA in patients with low baseline viral load at 4, 12 and 24 weeks were 92.3%, 100% and 100%, while the rates of those with high baseline viral load were 68.2%, 94.1% and 94.4%. Compared with 71.4%, 94.4% and 94.7% in the high baseline group, the undetectable rates of HBV DNA at 4, 12 and 24 weeks in the low baseline liver stiffness group were 85.7%, 100% and 100%. There was no statistical significance among the above groups.

CONCLUSIONS

CHB patients who had normal ALT and detectable HBV DNA and did not meet "CHB prevention guide (2019)", could achieve complete virological response in 24 weeks after antiviral treatment by TAF.

Circadian clock and liver energy metabolism

Circadian rhythm, generated by the circadian clock, is an internal rhythm that the body evolved to adapt to the diurnal changes in the external environment. Under its influence, mammals have distinct feeding and fasting cycles, which cause rhythmic changes in nutrient supply and demand. In recent years, many studies have shown that biorhythms are closely related to body metabolism. The liver, as the metabolism center of the body, is affected by circadian rhythm. However, with the acceleration of the pace of modern life and the change of life styles, the body's original rhythm is disrupted, resulting in a significant increase in the incidence of liver related metabolic diseases. Meanwhile, the disorder of circadian rhythm can also promote the occurrence and development of these diseases, and affect their prognosis and outcome. This paper reviews the relationship between the function of liver clock genes and the metabolism of liver glucose, lipids, bile acids, protein, etc.

[Value of CT in evaluating the risk of benign and malignant thyroid nodules]

Objective: To evaluate the value of CT in the risk assessment of thyroid benign nodules (BN) and malignant nodules (MN). Methods: The CT signs of 461 pieces of MN in 447 cases and 548 pieces of BN in 484 cases were retrospectively analyzed, the diagnoses were confirmed by histology, including nodular morphology, cookie bite sign, microcalcification, enhanced range narrow/blurred, cystic changes and enhanced.The signs of CT were analyzed by univariate and multivariate regression analysis.The positive CT signs were calculated to assess sensitivity and specificity in the diagnosis of BN and MN. Results: Univariate and multivariate analysis showed that irregular nodular morphology (χ(2)=509.263, P<0.001, OR=5.297), cookie bite sign (χ(2)=504.619, P<0.001, OR=3.467), microcalcification (χ(2)=97.793, P<0.001, OR=1.730), enhanced range reduction/blur (χ(2)=361.967, P<0.001, OR=5.729) were more common in MN.Cysts changes (χ(2)=223.208, P<0.001, OR=7.537) and enhancement signs (χ(2)=65.983, P<0.001, OR=10.782) were more common in BN.The sensitivity and specificity of irregular nodular morphology in the diagnosis of MN were 80.5% and 90%, those in cookie bite sign were 74.2% and 94.3%, microcalcification were 35.6% and 90.1%, enhanced range reduction/blur were 80.7% and 79.4%.The sensitivity and specificity of capsule-based and high-enhanced BN diagnosis were 42.2% and 98.1%, 19.0% and 97.4%, respectively. Conclusions: Irregular shape, cookie bite sign, microcalcification and enhanced range of narrowing/blur are significant CT signs in the assessment of MN, and cystic changes and enhancement are significant CT signs in the evaluation of BN.The diagnostic efficiency of various CT signs varies greatly, and combination of multiple CT signs can improve the diagnostic efficiency.

Pharmacological actions of nerve growth factor-transferrin conjugate on the central nervous system

Transferrin (Tf) undergoes receptor-mediated transport through the blood-brain barrier in vivo. This property allows transferrin to act as a vector for drug transport to the brain. The present investigation examines both the profile of brain delivery of nerve growth factor (NGF)-transferrin conjugate, and its therapeutic effects on CNS neurodegeneration, which affect locomotion and memory. Delivery of NGF-Tf conjugate to the brain was measured and found to be 0.075% of the injected dose per gram of brain, which is 5-fold higher than that of biotin-NGF. The increased delivery using the NGF-Tf conjugate can be attributed to an increased BBB permeability surface area product, which is about 8-fold higher than that of biotin-NGF. Intravenous injection of biotin-NGF/Tf-avidin conjugate significantly increased neuronal survival in the substantia nigra of a Parkinson's disease mouse model. In addition, this conjugate also improved recognition and memory in Alzheimer's disease rat model. In summary, these results demonstrate that using transferrin as a delivery vector is effective in targeting NGF to the central nervous system (CNS), and may optimize the therapy of age-related neurodegenerative diseases.

Effect of moisture on the extraction efficiency of polycyclic aromatic hydrocarbons from soils under atmospheric pressure by focused microwave-assisted extraction

The effects of the moisture content in the original, air-dried and re-moistened matrices as well as solvent have been studied on the recovery of polycyclic aromatic hydrocarbons (PAHs) from soil by a focused microwave-assisted extraction (FMAE) method. Solvents selected for the extractions were cyclohexane-acetone (1:1), hexane-acetone (1:1) and dichloromethane. On the extraction of 20-day aged spiked soil, the highest recovery was found by applying hexane-acetone mixture. Spiked soil sample, quality control sample and real soil sample were used for the evaluation of moisture effect. It indicated that the presence of water in the soil is important for the recovery enhancement of PAHs and with this presence it is possible to avoid drying step with the FMAE technique. A comparison between microwave and 16-h Soxhlet methods has been made. It evidenced that the microwave-assisted extraction under ambient atmospheric pressure is a suitable alternative to Soxhlet extraction for the analysis of PAHs in soils.

Analysis of polycyclic aromatic hydrocarbons in sediment reference materials by microwave-assisted extraction

The microwave-assisted extraction (MAE) of polycyclic aromatic hydrocarbons (PAHs) from harbor sediment reference material EC-1, marine sediment reference material HS-2 and PAH-spiked river bed soil was conducted. The extraction conditions for EC-1 were carried out at 70 degrees C and 100 degrees C under pressure in closed vessels with cyclohexane acetone (1:1), cyclohexane-water (3:1), hexane acetone (1:1), and hexane-water (3:1) for 10 min. A comparison between MAE and a 16-h Soxhlet extraction (SX) method showed that both techniques gave comparable results with certified values. MAE has advantages over the currently used Soxhlet technique due to a faster extraction time and lower quantity of solvent used. The consumption of organic solvent of the microwave method was less than one-tenth compared to Soxhlet.

Brain delivery of biotinylated NGF bounded to an avidin-transferrin conjugate

Recent study showed that transferrin receptors were concentrated on the plasma membrane of brain endothelia cells and mediated transcytosis of transferrin (Tf) through the blood-brain barrier (BBB). This property allows the transferrin to act as the brain drug transporter vector. The present investigation examined the pharmacokinetic behavior of nerve growth factor (NGF), which was conjugated to transferrin by the avidin/biotin technology, especially its brain-uptake efficiency. The area under the plasma concentration curve and the mean residence time were not significantly different for either bio-NGF or bio-NGF/AV-Tf. At the first hour after single intravenous injection, the BBB permeability surface area product of bio-NGF/AV-Tf was 0.77 microliter/min/g; it was about 8-fold higher than that of bio-NGF, and equal to that of AV-OX26. The delivery of bio-NGF/AV-Tf to brain was 0.075% of injected dose per gram brain, and it was 5-fold higher than that of bio-NGF, and 2-fold higher than that of AV-OX26. In summary, these studies demonstrated that the use of Tf as brain drug delivery vector was as effective in transporting biotinylated therapeutics as OX26, and avoided the disadvantages of its antigenicity.

Bioactivities of nerve growth factor from Chinese cobra venom

The nerve growth factor, NGF, from Chinese cobra Naja naja atra venom was isolated by gel-filtration and ion-exchange chromatography. Cobra NGF was characterized by analytical HPLC techniques as well as SDS-PAGE, and was proven to be a glycoprotein with a mol. wt. of 23 (+/- 2) kD and a pI of 9.2. The amino acid analysis and N-terminal sequencing were performed using conventional methods. Bioassays with cultured chick embryos ganglia and rat pheochromocytoma PC-12 cells revealed a promotion of fiber outgrowth, which is typical of NGF activity. Absence of enzymatic, toxicological, and teratogenic activities were shown by quality inspection. Since 1994, many clinical cases about volunteers receiving NGF treatment have been reported in mainland China. Bioactivities of NGF deal with a wide range of disciplines and technologies. In this paper we will discuss neuronal and non-neuronal effects of NGF treatment. Does the NGF cross the blood-brain barrier by transcytosis into the brain tissue? How is NGF important in wound healing, especially in peripheral nerve injury and diabetic neuritis? NGF may also be useful for male volunteers suffering from sterility, because it is possible that the sexual cells of testis can be promoted to maturity.

A thrombin-like enzyme from timber rattlesnake venom

The procoagulant component has been purified from timber rattlesnake (Crotalus horridus horridus) venom by DEAE-cellulose ion-exchange chromatography followed by affinity chromatography on immobilized p-aminobenzamidine and a final DEAE-Sepharose chromatography. As obtained, the procoagulant gave a single band of Mr 29 500 +/- 2000 on SDS-polyacrylamide gel electrophoresis whether or not the sample was reduced prior to electrophoresis. Schiff's stain indicated the presence of some carbohydrate. The procoagulant showed one predominant and four minor bands on discontinuous gel electrophoresis. All caused fibrinogen solutions to clot. Treatment of the preparation with neuraminidase did not cause the minor bands to comigrate with the major band. Amino acid analysis revealed the presence of eight half-cystines, all of which were present as cystines in the intact molecule. The procoagulant has 13 tryptophans per molecule and an extinction coefficient for a 1% solution at 280 nm of 26.3. This venom procoagulant was found to induce clotting by catalyzing the hydrolysis of only the A fibrinopeptide from the A alpha-chain of fibrinogen. It was not inhibited by protein trypsin inhibitors, N-ethylmaleimide or dithiothreitol, but it was inactivated by phenylmethylsulfonyl fluoride, indicating an active-center serine. The procoagulant catalyzed the release of negligible acid-soluble peptides from bovine serum albumin, casein and hemoglobin.