Rosuvastatin Intervention Decreased the Frequencies of the TIM-3+ Population of NK Cells and NKT Cells among Patients with Chronic Hepatitis B.

BACKGROUND: Natural killer (NK) cells are dichotomously involved in chronic hepatitis B (CHB) infection as principal members of innate immunity. An effective treatment should enhance the antiviral potentials of NK cells and not their immunomodulatory roles. TIM-3 (T-cell immunoglobulin and mucin-containing domain) is a molecule with an essential role in controlling immune tolerance. TIM-3 demonstrated the highest expression among NK cells of patients with chronic liver disorders. Statins have been reported to attenuate the levels of TIM-3 on NK cells. OBJECTIVES: To investigate the frequencies of NK cells, NKT cells, and TIM-3+ population in patients with CHB upon rosuvastatin (RSV) intervention. METHODS: Thirty confirmed patients with CHB were randomly assigned into two groups of 15 (receiving 20 mg of RSV or placebo per day) for 12 weeks. We evaluated the percentages of TIM-3+ cells by staining the peripheral blood mononuclear cells (PBMCs) with CD3, CD16, and CD56 markers using flow cytometry. RESULTS: Our findings indicated that RSV administration could increase CD3- CD56+ NK cells (P>0.05) and CD3+ CD16+ CD56+ NKT cells (P<0.05). RSV intervention could reduce the percentages of TIM-3+ cells among NK cells (P<0.01) and NKT cells (P> 0.05) of patients with CHB compared with the placebo group. CONCLUSIONS: The increased population of NK and NKT cells and the effective reduction of TIM-3+ cells among patients with CHB delineated that rosuvastatin could be proposed as an appropriate modulator of innate immune response (regarding NK and NKT cells) in favor of enhancing their antiviral activities.

The hepatoprotective effects of taurine against oxidative stress induced by isotretinoin in rats.

Liver disorders are one of the principal reasons for mortality in the world. Isotretinoin is a systemic retinoid that has been approved for therapy of acne vulgaris since 1982. This drug causes complications in the body. Evidence suggests that Isotretinoin might cause hepatotoxicity. Our research aimed to study the exact mechanism of hepatotoxicity induced by isotretinoin and the protective role of taurine in this toxicity. Biomarkers such as aspartate transaminase (AST) and alanine transaminase (ALT), superoxide dismutase, glutathione content (GSH), catalase, and malondialdehyde (MDA) were examined. Furthermore, pathological changes were evaluated. The results showed that oral administration of Isotretinoin induced hepatotoxicity as showed by elevation in ALT, AST, and MDA; also, it reduced intracellular GSH in rat liver tissue. Administration of taurine prevented the hepatotoxicity induced by isotretinoin in rats significantly.

Cytoprotective Effects of Melatonin Against Amitriptyline-Induced Toxicity in Isolated Rat Hepatocytes.

PURPOSE: Amitriptyline, one of the commonly used tricyclic antidepressants, caused rare but severe hepatotoxicity in patients who received it continuously. Previous findings showed that the intermediate metabolites of amitriptyline produced by CYP450 are involved in hepatic injury. Melatonin is an antiaging and antioxidant hormone synthesized from pineal gland. The aim of present study was to evaluate the protective role of melatonin in an in vitro model of isolated rat hepatocytes. METHODS: Markers such as cell viability, reactive oxygen species formation, lipid peroxidation, mitochondrial membrane potential, and hepatocytes glutathione content were evaluated every 60 minutes for 180 minutes. RESULTS: Present results indicated that administration of 1mM of melatonin effectively reduced the cell death, ROS formation and lipid peroxidation, mitochondrial membrane potential collapse, and reduced cellular glutathione content caused by amitriptyline. CONCLUSION: Our results indicated that melatonin is an effective antioxidant in preventing amitriptyline-induced hepatotoxicity. We recommend further in vivo animal and clinical trial studies on the hepatoprotective effects of melatonin in patients receiving amitriptyline.

Mechanisms of phenytoin-induced toxicity in freshly isolated rat hepatocytes and the protective effects of taurine and/or melatonin.

Phenytoin is a widely used antiepileptic drug. However, hepatotoxicity is one of its adverse effects reported in some patients. The mechanism(s) by which phenytoin causes hepatotoxicity is not clear yet. This study was designed to evaluate the cytotoxic mechanism(s) of phenytoin toward rat hepatocytes (whose cytochrome P450 enzymes had been induced by Phenobarbital). Furthermore, the effect of taurine and/or melatonin on this toxicity was investigated. Cell death, reactive oxygen species (ROS) formation, lipid peroxidation (LPO), and mitochondrial depolarization were monitored as toxicity markers. Results showed that phenytoin caused an elevation in ROS formation, depletion of intracellular reduced glutathione, increase in cellular oxidized glutathione, enhancement of LPO, and mitochondrial damage. Taurine (1 mM) and/or melatonin (1 mM) administration decreased the intensity of cellular injury caused by phenytoin. This study suggests the protective role of taurine and/or melatonin against phenytoin-induced cellular damage probably through their reactive radical scavenging properties and their effects on mitochondria.

Mechanisms of trazodone-induced cytotoxicity and the protective effects of melatonin and/or taurine toward freshly isolated rat hepatocytes.

It has been reported that the bioactive intermediate metabolites of trazodone might cause hepatotoxicity. This study was designed to investigate the exact mechanism of hepatocellular injury induced by trazodone as well as the protective effects of taurine and/or melatonin against this toxicity. Freshly isolated rat hepatocytes were used. Trazodone was cytotoxic and caused cell death with LC50 of 300 µm within 2 h. Trazodone caused an increase in reactive oxygen species (ROS) formation, malondialdehyde accumulation, depletion of intracellular reduced glutathione (GSH), rise of oxidized glutathione disulfide (GSSG), and a decrease in mitochondrial membrane potential, which confirms the role of oxidative stress in trazodone-induced cytotoxicity. Preincubation of hepatocytes with taurine prevented ROS formation, lipid peroxidation, depletion of intracellular reduced GSH, and increase of oxidized GSSG. Taurine could also protect mitochondria against trazodone-induced toxicity. Administration of melatonin reduced the toxic effects of trazodone in isolated rat hepatocytes.

Protective role of melatonin and taurine against carbamazepine-induced toxicity in freshly isolated rat hepatocytes / Rol protector de la melatonina y taurina contra la toxicidad inducida por la carbamazepina en hepatocitos de rata recién aislados

Carbamazepine is widely used in a broad spectrum of psychiatric and neurological disorders. Idiosyncratic hepatotoxicity is a well-known adverse reaction associated with carbamazepine. Hepatotoxicity is rare, but a real concern when initiating therapy. It was found that oxidative stress is a potential mechanism for carbamazepine-induced hepatotoxicity. Present study evaluated the hepato protective role of taurine and melatonin against carbamazepine-induced hepatotoxicity. Hepatocytes were prepared by the method of collagenase enzyme perfusion via portal vein. Cells were treated with 400 uM carbamazepine, 1mM taurine, and 1mM melatonin. Cell death, reactive oxygen species formation, lipid peroxidation, and mitochondrial membrane depolarization were assessed as toxicity markers and the effects of taurine and melatonin administration on them were investigated. Our results showed that carbamazepine induced oxidative stress; increased ROS formation and lipid peroxidation products and also decreased mitochondrial membrane potential (DYm). Carbamazepine caused a decrease in cellular glutathione content and an elevation in oxidized glutathione levels. Our investigation showed that preincubation of hepatocytes with taurine (1 mM) could alleviate oxidative damages induced by carbamazepine; melatonin was also a good antioxidant to protect hepatocytes against cytotoxicity induced by carbamazepine. It may be concluded that taurine and melatonin are effective antioxidants to prevent carbamazepine-induced hepatotoxicity. Following our findings, further studies are suggested on the antioxidant effects of taurine and melatonin in patients receiving carbamazepine.

La carbamazepina es ampliamente utilizada en un gran espectro de trastornos psiquiátricos y neurológicos. La hepatotoxicidad idiosincrásica es una conocida reacción adversa asociada con la carbamazepina. La hepatotoxicidad es rara, pero es una preocupación real al iniciar el tratamiento. Se ha reportado que el estrés oxidativo es un potencial mecanismo para la hepatotoxicidad inducida por carbamazepina. El presente estudio evaluó la función hepato-protectora de la taurina y melatonina contra la hepatotoxicidad inducida por carbamazepina. Los hepatocitos se prepararon por el método de perfusión de la enzima colagenasa a través de la vena porta. Las células fueron tratadas con 400 uM de carbamazepina, 1 mM de taurina, y 1 mM de melatonina. La muerte celular, formación de especies reactivas de oxígeno (ERO), peroxidación de lípidos, y despolarización de la membrana mitocondrial fueron evaluadas como marcadores de toxicidad, junto con investigar los efectos de la taurina y melatonina administrada en ellos. Nuestros resultados mostraron estrés oxidativo inducido por carbamazepina, con aumento de las ERO, formación de productos de la peroxidación lipídica y disminución del potencial de membrana mitocondrial (DYm). La carbamazepina causó una disminución en el contenido celular de glutatión y una elevación de los niveles de glutatión no-oxidado. Se observó que la preincubación de los hepatocitos con taurina (1 mM) podría aliviar los daños oxidativos inducidos por carbamazepina; además la melatonina también fue un buen antioxidante para proteger a los hepatocitos. Se puede concluir que tanto la taurina y melatonina son antioxidantes eficaces para prevenir la hepatotoxicidad inducida por carbamazepina. Tras nuestros resultados, se sugiere estudiar los efectos antioxidantes de la taurina y melatonina en pacientes tratados con carbamazepina.