Can we reduce oxidative stress with liver transplantation?

m-Cresol,a pesticide intermediate, induces hepatotoxicity and behavioral abnormalities in zebrafish larvae through oxidative stress, apoptosis

m-Cresol is mainly used as a pesticide intermediate. It is industrially used in the production of insecticides including boronone and fenthion. It is also an intermediate for color film, resins, plasticizers and fragrances. However, m-cresol has the potential to cause environmental contamination if released accidentally. The molecular mechanism of m-cresol mediated hepatotoxicity remains unclear. In this study, zebrafish larvae were used to comprehensively study the hepatotoxicity of m-cresol and explore its molecular mechanism. After 72 hpf of fertilization, zebrafish larvae were exposed to 0.2 mM,0.4 mM, and 0.6 mM of m-cresol. Varying degrees of liver injury and behavioral abnormalities were observed. The hepatotoxicity of zebrafish larvae may be induced by oxidative stress pathway and apoptosis of cell.

Investigation of Oxidative Stress Level and Antioxidant Enzyme Activities in Operated and Nonoperated Patients with Spontaneous Intracerebral Hematoma

BACKGROUND

 Complex underlying mechanisms consisting of cytotoxic, excitotoxic, and inflammatory effects of intraparenchymal hemorrhage (ICH) are responsible for the highly detrimental effects on brain tissue. Oxidative stress also plays a significant role in brain damage after ICH; however, it is less important than other factors. In this study, we aimed to evaluate the oxidative stress parameters malondialdehyde (MDA) and antioxidant-reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CT) activities in operated and nonoperated patients with spontaneous ICH.

METHODS

 One hundred patients with spontaneous ICH and 100 healthy controls were included in this study. Within the indication, 50 of the 100 patients underwent decompressive surgery. MDA, GSH, SOD, and CT activities were measured in the serum obtained from the patients.

RESULTS

 SOD and CT levels were lower in the nonoperated group than in the operated and control groups. GSH was similar in the operated and nonoperated groups, but it was lower in the control group. However, MDA was higher in those who did not undergo surgery than in the other groups.

CONCLUSIONS

 In our study, MDA, an indicator of oxidative stress, was found to be lower, and CT and SOD activities were found to be higher in ICH patients who underwent decompression than in those who did not. This is the first study to present the correlations of MDA, SOD, CT, and GSH in operated and nonoperated patients with spontaneous ICH.

Comparison of in-gel and in-solution proteolysis in the proteome profiling of organ perfusion solutions

PURPOSE

The organ perfusion solution (perfusate), collected at clinically and temporally significant stages of the organ preservation and transplantation process, provides a valuable insight into the biological status of an organ over time and prior to reperfusion (transplantation) in the recipient. The objective of this study was to assess two bottom-up proteomics workflows for the extraction of tryptic peptides from the perfusate.

EXPERIMENTAL DESIGN

Two different kinds of perfusate samples from kidney and liver trials were profiled using liquid chromatography-mass spectrometry (LC-MS/MS). The preparation of clean peptide mixtures for downstream analysis was performed considering different aspects of sample preparation; protein estimation, enrichment, in-gel and urea-based in-solution digestion.

RESULTS

In-solution digestion of perfusate allowed identification of the highest number of peptides and proteins with greater sequence coverage and higher confidence data in kidney and liver perfusate. Key pathways identified by gene ontology analysis included complement, coagulation and antioxidant pathways, and a number of biomarkers previously linked to ischemia-reperfusion injury were also observed in perfusate.

CONCLUSIONS

This study showed that in-solution digestion is a more efficient method for LC-MS/MS analysis of kidney and liver organ perfusion solutions. This method is also quicker and easier than in-gel digestion, allowing for greater sample throughput, with fewer opportunities for experimental error or peptide loss.

An in vivo and in silico evaluation of the hepatoprotective potential of Gynura procumbens: A promising agent for combating hepatotoxicity

INTRODUCTION

The liver, the most important metabolic organ of the body, performs a wide variety of vital functions. Hepatic cell injury occurs by the activation of reactive oxygen species (ROS) that are generated by carbon tetrachloride (CCl4), xenobiotics, and other toxic substances through cytochrome P450-dependent steps resulting from the covalent bond formation with lipoproteins and nucleic acids. Observing the urgent state of hepatotoxic patients worldwide, different medicinal plants and their properties can be explored to combat such free radical damage to the liver. In vivo and in silico studies were designed and conducted to evaluate the antioxidant and hepatoprotective properties of Gynura procumbens in rats.

MATERIALS AND METHODS

Gynura procumbens leaves were collected and extracted using 70% ethanol. The required chemicals CCl4, standard drug (silymarin), and blood serum analysis kits were stocked. The in vivo tests were performed in 140 healthy Wister albino rats of either sex under well-controlled parameters divided into 14 groups, strictly maintaining Institutional Animal Ethics Committee (IEAC) protocols. For the histopathology study, 10% buffered neutral formalin was used for organ preservation. Later the specimens were studied under a fluorescence microscope. In silico molecular docking and absorption, distribution, metabolism, excretion, and toxicity (ADMET) studies were performed, and the results were analyzed statistically.

RESULTS AND DISCUSSION

Gynura procumbens partially negate the deleterious effect of carbon tetrachloride on normal weight gain in rats. The elevated level of serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), creatinine, LDH, total cholesterol (TC), low-density lipoprotein (LDL), triglycerides (TG), malondialdehyde (MDA), deoxyribonucleic acid (DNA) fragmentation ranges, gamma-glutamyl transferase (γ-GT) in CCl4 treated groups were decreased by both standard drug silymarin and G. procumbens leaf extract. We have found significant & highly significant changes statistically for different doses, here p<0.05 & p<0.01, respectively. On the other hand, G. procumbens and silymarin displayed Statistically significant (p<0.05) and high significant(p<0.01) increased levels of HDL, CAT SOD (here p<0.05 & p<0.01 for different doses) when the treatment groups were compared with the disease control group. Because the therapeutic activity imparted by plants and drugs accelerates the movement of the disturbed pathophysiological state toward the healthy state. In the molecular docking analysis, G. procumbens phytoconstituents performed poorly against transforming growth factor-beta 1 (TGF-β1) compared to the control drug silymarin. In contrast, 26 phytoconstituents scored better than the control bezafibrate against peroxisome proliferator-activated receptor alpha (PPAR-α). The top scoring compounds for both macromolecules were observed to form stable complexes in the molecular dynamics simulations. Flavonoids and phenolic compounds performed better than other constituents in providing hepatoprotective activity. It can, thus, be inferred that the extract of G. procumbens showed good hepatoprotective properties in rats.

Measurement of oxidant and antioxidant levels in liver tissue obtained from patients with liver transplantation: A case-control study

OBJECTIVE

This study aimed to compare oxidant and antioxidant substance accumulation in the liver tissues of patients with chronic liver disease (recipients) who underwent liver transplantation (LT) with living liver donors (LLDs) who underwent living donor hepatectomy (LDH).

METHODS

This prospective study included 160 recipients (LT group) and 40 LLDs (LLD group). During surgery, a piece of liver tissue measuring a minimum of 10 × 10 mm was obtained from the edge of the right lobe of the liver of recipients and LLDs, incubated for 10 min in saline to remove blood, and stored at -70 °C until biochemical analysis was performed. Catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), myeloperoxidase (MPO), prolidase, reduced glutathione (GSH), malondialdehyde (MDA), total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), total thiol, native thiol, and disulfide levels were measured in stored liver tissues.

RESULTS

There was a statistically significant difference between LT and LLD groups in terms of age (p < 0.001), body mass index (p = 0.019), GSH-Px (p < 0.001), SOD (p = 0.001), MPO (p < 0.001), prolidase (p < 0.001), GSH (p < 0.001), and MDA (p = 0.003) values in favor of the LT group. Furthermore, there was a statistically significant difference between LT and LLD groups in terms of CAT (p < 0.001), TAS (p < 0.001), TOS (p < 0.001), OSI (p < 0.001), total thiol (p < 0.001), native thiol (p < 0.001), and disulfide (p < 0.001) values in favor of the LLD group. There were no differences between the groups in terms of sex.

CONCLUSION

This study demonstrated that it is possible to assess the extent of oxidative stress in liver tissues by measuring the levels of antioxidant enzymes, oxidants, or the end-products of oxidative stress. With the use of optimum and minimally invasive methods, quantifying these molecules will potentially help evaluate the extent of liver disease and prognostication of liver cirrhosis.

ANOM Approach for Statistical Evaluation of Some Antioxidant Enzyme Activities

Free radicals are chemical molecules that are more reactive and have an unpaired electron. Free radicals formed inside the cell oxidize biomolecules, leading to cell death and tissue damage. Antioxidants are molecules that can stabilize or inactivate free radicals before they damage the cell. In this study; the availability of Malondialdehyde, Superoxide dismutase, Catalase and Reduced glutathione levels as markers for related diseases was evaluated by examining whether and in what range they may vary in some diseases. In study, nine groups consist of prostate cancer, cirrhosis, liver transplantation, chronic kidney damage, acute kidney injury, X-ray exposure, CT exposure, MR exposure and Osteonecrosis. Analysis of means is a method developed to compare group means with the overall mean and presents the results graphically in an easy-to-understand manner without the required for any post hoc test. In addition, related characteristics were categorized as “low and high” and Nonlinear Principal Component Analysis was conducted to visually present their relationship with related disease types in two-dimensional space. The upper and lower decision lines were found 3.123 and 2.794 μmol/L, respectively for Malondialdehyde. Those with cirrhosis, chronic kidney disease, acute kidney disease and tomography exposure were included in the upper and lower decision lines. Those with prostate cancer, osteonecrosis, and X-ray exposure were above the upper decision line and are found higher than the overall mean. Those with lung transplantation and MR exposure appear to be below the lower decision line and lower than the overall mean. The present study provides the first comprehensive assessment of the availability of Malondialdehyde, Superoxide dismutase, Catalase and Reduced glutathione levels as markers for some related diseases. This study has shown that Analysis of means can be used as an alternative graphical procedure for multiple group comparisons with an overall mean in the studies regarding as biochemical characteristics and relating diseases. In addition, Nonlinear Principal Component Analysis can be useful aid for decision marker in some biochemical characteristics and related diseases.

Fibroblast Growth Factor 21 Augments Autophagy and Reduces Apoptosis in Damaged Liver to Improve Tissue Regeneration in Zebrafish

Regeneration of a part of the diseased liver after surgical resection is mainly achieved by the proliferation of the remaining healthy liver cells. However, in case of extreme loss of liver cells or in the final stages of chronic liver disease, most liver cells are depleted or lose their ability to proliferate. Therefore, to foster liver regeneration, it is of great clinical and scientific significance to improve the survival and proliferation ability of residual hepatocytes. In this study, we conducted experiments on a zebrafish model of targeted ablation of liver cells to clarify the role of fibroblast growth factor 21 (FGF21). We found that FGF21 increased the regeneration area of the damaged liver and improved the survival rate of damaged liver cells by inhibiting cell apoptosis and reducing oxidative stress. Our results also showed that administration of FGF21 upregulated autophagy, and the beneficial effects of FGF21 were reversed by the well-known autophagy inhibitor chloroquine (CQ), indicating that FGF21-activated autophagy played a central role in the treatment. We further showed that the enhancement of autophagy induced by FGF21 was due to the activation of the AMPK-mTOR signaling pathway. Taken together, these data provide new evidence that FGF21 is an effective autophagy regulator that can significantly improve the survival of damaged livers.