Factors affecting drug-induced liver injury: antithyroid drugs as instances

Methimazole and propylthiouracil have been used in the management of hyperthyroidism for more than half a century. However, hepatotoxicity is one of the most deleterious side effects associated with these medications. The mechanism(s) of hepatic injury induced by antithyroid agents is not fully recognized yet. Furthermore, there are no specific tools for predicting the occurrence of hepatotoxicity induced by these drugs. The purpose of this article is to give an overview on possible susceptibility factors in liver injury induced by antithyroid agents. Age, gender, metabolism characteristics, alcohol consumption, underlying diseases, immunologic mechanisms, and drug interactions are involved in enhancing antithyroid drugs-induced hepatic damage. An outline on the clinically used treatments for antithyroid drugs-induced hepatotoxicity and the potential therapeutic strategies found to be effective against this complication are also discussed

Evaluating the effects of different fractions obtained from Gundelia tournefortii extract against carbon tetrachloride-induced liver injury in rats

Xenobiotics-induced liver injury is a major challenge for clinicians and pharmaceutical industry. Hence, finding new therapeutic molecules against this complication has clinical value. The current investigation aimed to evaluate the potential protective effects of different fractions obtained from Gundelia tournefortii (GT) hydroalcoholic extract in a rat model of acute hepatic injury. Male Sprague-Dawley rats (200‑250 g) were treated with carbon tetrachloride (CCl4) (1.5 ml/kg, i.p), then ethanol, water, chloroform, ethyl acetate, and n-Butanol fractions of GT extract were administered. Biochemical and histopathological markers of hepatic injury were assessed and glutathione (GSH) and lipid peroxidation were monitored in liver samples. CCl4 administration caused hepatotoxicity as revealed by an increase in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) activity, as well as pathological changes of the liver. Furthermore, a significant reduction in hepatic glutathione content and an elevation in lipid peroxidation were observed in CCl4‑treated rats. It was found that the n‑butanol (200 mg/kg) and the ethyl acetate (300 mg/kg) fractions of GT extract protected liver against CCL4‑induced damage as judged by lower AST, ALT, LDH and lipid peroxidation, prevention of tissue glutathione depletion, and alleviation of histopathological damages of liver in extract‑treated animals. As n‑butanol and the ethyl acetate fractions of GT effectively alleviated the liver injury induced by CCl4 and provide antioxidant properties, we might be able to propose that the hepatoprotective chemicals of Gundelia extract are present in these fractions.</p

The Hepatoprotective Role of Thiol Reductants against Mitoxantrone-Induced Liver Injury

Mitoxantrone is anthracycline antibiotic highly effective against various human cancers. Hepatotoxicity is associated with mitoxantrone administration. On the other hand, there is no effective therapeutic option against chemotherapy-induced liver injury. The current investigation was designed to evaluate the effect of thiol reductants on mitoxantrone-induced liver injury in two experimental models. As an ex vivo model, isolated rat liver was exposed to increasing concentrations of mitoxantrone (100, 250, 750, and 1000 µM) alone or in combination with thiol-reductants (Dithiothreitol; DTT, and N-acetyl cysteine; NAC). In addition, rats (in vivo) received mitoxantrone (2.5 mg/kg, i.p, at days 1, 10, and 20), NAC (100 and 300 mg/kg/day, i.p, for 20 consecutive days) and DTT (15 and 30 mg/kg/day, i.p, for 20 consecutive days), then liver and serum pathological changes were monitored. Mitoxantrone-induced liver injury was evident in both ex vivo and in vivo experiments as assessed by pathological changes in biomarkers of liver injury, along with tissue histopathological changes. Furthermore, an increase in liver tissue markers of oxidative stress was detected in the mitoxantrone-treated group. It was found that thiol reductants significantly mitigated mitoxantrone hepatotoxicity. The data indicate that thiol reductants might serve as hepatoprotective agents against chemotherapy-induced liver injury.</p

Carnosine Supplementation Mitigates Brain Tissue Markers of Oxidative Stress in a Rat Model of Fulminant Hepatic Failure

Fulminant hepatic failure is a deleterious clinical complication, which leads to hyperammonemia. Ammonia is a noxious neurotoxic agent, which affects brain tissue through different mechanisms. On the other hand, it is well-known that oxidative stress and its consequences play a major role in the pathogenesis of ammonia-induced brain injury. Carnosine is a dipeptide abundantly found in the human central nervous system (CNS). This peptide is widely investigated for its neuroprotective properties. The current study aimed to evaluate the effect of carnosine supplementation on oxidative stress markers in the brain tissue of a rat model of fulminant hepatic failure and hyperammonemia. Animals received thioacetamide (400 mg/kg, i.p, for three consecutive days at 24-hr intervals) as a model of acute liver failure and hyperammonemia. Several serum biochemical parameters, in addition to plasma and brain ammonia level, were monitored. On the other hand, brain tissue markers of oxidative stress including reactive oxygen species (ROS) formation, lipid peroxidation, tissue glutathione content, and total antioxidant capacity were measured. It was found that plasma and brain ammonia was increased, and serum markers of liver injury were significantly elevated in the thioacetamide-treated group. On the other hand, an increase in markers of oxidative stress, including ROS formation, lipid peroxidation, glutathione depletion, and decreased tissue antioxidant capacity, was evident in the brain of thioacetamide-treated animals. It was found that carnosine supplementation (250, 500, and 1000 mg/kg) decreased serum markers of liver injury, mitigated brain, and plasma ammonia level, and alleviated brain tissue markers of oxidative stress. These data suggest carnosine as a potential neuroprotective agent with therapeutic capability against ammonia-induced CNS injury.</p

Taurine Alleviates Brain Tissue Markers of Oxidative Stress in a Rat Model of Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a serious clinical complication, which could lead to coma and death if not appropriately managed. There is agreement on the predominant role of ammonia in the etiology of HE. Brain is one of the most critical organs affected by ammonia. The critical role of oxidative stress and its consequences in the pathogenesis of ammonia-induced brain injury have been revealed before. On the other hand, there is no promising therapeutic option against ammonia neurotoxicity. Taurine is one of the most abundant amino acids in the human body. Several pharmacological roles including brain protecting properties have been attributed to this amino acid. The current study was designed to evaluate the role of taurine supplementation on HE-induced oxidative stress in the brain tissue. Animals received thioacetamide (400 mg/kg, i.p, for three consecutive days at 24-hr intervals) as a model of acute liver failure and hyperammonemia. Several serum biochemical parameters, in addition to plasma and brain ammonia level, were monitored. Moreover, markers of oxidative stress in the brain of hyperammonemic animals were assessed. It was found that plasma and brain ammonia was increased, and serum markers of liver injury were significantly elevated in the thioacetamide-treated group. On the other hand, an increase in markers of oxidative stress, including reactive oxygen species formation, lipid peroxidation, glutathione depletion, and decreased tissue antioxidant capacity, was detected in the brain tissue of thioacetamide-treated animals. It was found that taurine treatment (250, 500, and 1000 mg/kg, i.p) alleviated brain tissue markers of oxidative stress and decreased serum biomarkers of liver injury. Furthermore, lower plasma and brain ammonia were detected in taurine-treated animals. These data suggest taurine as a potential protective agent with therapeutic capability against HE-associated central nervous system complications.</p

Sildenafil Blunts Lung Inflammation and Oxidative Stress in a Rat Model of Cholestasis

Background: Cholestasis is a multifaceted disease that influences not only the function of the liver but also affects many other organs. In this context, cholestasis-induced lung injury is a significant clinical complication. Unfortunately, there is no precise therapeutic option against cholestasis-associated lung injury. It has been revealed that oxidative stress and inflammatory response play a role in cholestasis-induced pulmonary damage. Sildenafil is a phosphodiesterase enzyme inhibitor used in the management of erectile dysfunction. Meanwhile, several experiments revealed the effects of sildenafil on oxidative stress and inflammation. This study aimed to evaluate the effect of sildenafil on cholestasis-induced oxidative stress and inflammation in cholestasis-induced lung injury. Methods: Rats underwent bile duct ligation (BDL) to induce cholestasis. Bronchoalveolar lavage fluid (BALF) levels of inflammatory cells, cytokine, and immunoglobulin were monitored at (3, 7, and 14 days after BDL surgery). Moreover, lung tissue histopathological alterations and biomarkers of oxidative stress were evaluated. Results: A significant increase in BALF inflammatory cells, TNF-α, and immunoglobulin G (IgG) was evident in BDL animals. Moreover, the infiltration of inflammatory cells, vascular congestion, and hemorrhage were detected in the lung of BDL rats. Increased markers of oxidative stress were also evident in the lung of BDL animals. Sildenafil (10 and 20 mg/kg) significantly blunted inflammatory response, oxidative stress, and histopathological alterations in the lung of cholestatic animals. Conclusion: The effects of sildenafil on inflammatory response and oxidative stress biomarkers seems to play a crucial role in its protective properties in the lung of cholestatic animals

Dexamethasone Blunts Lung Inflammation in Cholestatic Mice

Cholestasis/cirrhosis is a multifaceted clinical complication that influences many organs, including the liver, kidney, heart, skeletal muscle, and lung. Cirrhosis-associated lung injury could lead to severe and lethal consequences, including acute respiratory syndrome and patient dearth. Unfortunately, there is no specific pharmacological intervention to manage cholestasis-induced lung injury. It has been revealed that severe inflammation and its associated complications, such as oxidative stress, are involved in the pathogenesis of cholestasis-associated pulmonary damage. The current study was designed to evaluate the role of dexamethasone (DXM) on lung inflammation in cholestatic mice. For this purpose, bile duct ligated (BDL) mice received DXM (1 and 2.5 mg/kg, i.p, 2 times/week) for 14 days. On day 15, the bronchoalveolar lavage fluid (BALF) was prepared. Several markers, including inflammatory cell infiltration, TNF-α, and IgG, were assessed in the BALF of BDL animals. Significant infiltration of inflammatory cells along with increased TNF-α and IgG were detected in the BALF of BDL mice (14 days after surgery). Moreover, significant ROS formation, glutathione depletion, lipid peroxidation, and protein carbonylation were evident in the lung tissue of the BDL group. It was found that DXM (1 and 2.5 mg/kg) significantly blunted inflammation and oxidative stress in the lung of cholestatic mice. Moreover, lung tissue histopathological changes, including inflammatory cell infiltration, were significantly mitigated in DXM-treated mice. These data offer the potential therapeutic effects of DXM against cholestasis-related complications. Therefore, patients with cholestasis-induced lung injury might benefit from repurposing DXM in clinical settings

The Hepatoprotection Provided by Taurine and Glycine against Antineoplastic Drugs Induced Liver Injury in an Ex Vivo Model of Normothermic Recirculating Isolated Perfused Rat Liver

Taurine (2-aminoethane sulfonic acid) is a non-protein amino acid found in high concentration in different tissues. Glycine (Amino acetic acid) is the simplest amino acid incorporated in the structure of proteins. Several investigations indicate the hepatoprotective properties of these amino acids. On the other hand, antineoplastic agents-induced serum transaminase elevation and liver injury is a clinical complication. The current investigation was designed to screen the possible hepatoprotective properties of taurine and glycine against antineoplastic drugs-induced hepatic injury in an ex vivo model of isolated perfused rat liver. Rat liver was perfused with different concentration (10 µM, 100 µM and 1000 µM) of antineoplastic drugs (Mitoxantrone, Cyclophosphamide, Cisplatin, 5‑Fluorouracil, Doxorubicin and Dacarbazine) via portal vein. Taurine and glycine were administered to drug-treated livers and liver perfusate samples were collected for biochemical measurements (ALT, LDH, AST, and K+). Markers of oxidative stress (reactive oxygen species formation, lipid peroxidation, total antioxidant capacity and glutathione) were also assessed in liver tissue. Antineoplastic drugs caused significant pathological changes in perfusate biochemistry. Furthermore, markers of oxidative stress were significantly elevated in drug‑treated livers. It was found that taurine (5 and 10 mM) and glycine (5 and 10 mM) administration significantly mitigated the biomarkers of liver injury and attenuated drug‑induced oxidative stress. Our data indicate that taurine and glycine supplementation might help as potential therapeutic options to encounter anticancer drugs-induced liver injury.</p

Thiol-reducing agents abate cholestasis-induced lung inflammation, oxidative stress, and histopathological alterations

Cholestasis is not only influences the hepatic function but also damages many other organs. Lung injury is a critical secondary organ damage associated with cholestasis/cirrhosis. Pulmonary histopathological alterations, respiratory distress, and hypoxia are related to cholestasis/cirrhosis-induced lung injury. It has been found that oxidative stress plays a crucial role in this complication. The current study was designed to investigate the effect of N-acetyl cysteine (NAC) and dithiothreitol (DTT) as thiol-reducing and antioxidant agents against cholestasis-induced lung injury. Bile duct ligated (BDL) rats were monitored for the presence of inflammatory cells, TNF-α, and IgG levels in their broncho-alveolar fluid (BALF) at scheduled time intervals (3, 7, 14, and 28 days post-BDL surgery). These markers reached their highest level in the BALF of BDL rats on day 28 after the surgery. Therefore, in another set of experiments, the BDL animals were treated with NAC (100 and 300 mg/kg/day, i.p, for 28 consecutive days) and DTT (10 and 20 mg/kg/day, i.p, for 28 consecutive days). Meanwhile, a significant increase in the levels of TNF-α and IgG was detected in the BALF of BDL rats. The BALF level of neutrophils, monocytes, and lymphocytes was also significantly increased in cholestatic animals. A significant increase in lung tissue biomarkers of oxidative stress was detected in the BDL rats. It was found that NAC and DTT could significantly blunt pulmonary damage induced by cholestasis. The effects of these agents on oxidative stress biomarkers and inflammatory response seem to play a pivotal role in their mechanisms of protective properties

Global, regional, and national cancer incidence, mortality, years of life lost, years lived with disability, and disability-Adjusted life-years for 29 cancer groups, 1990 to 2017 : A systematic analysis for the global burden of disease study

Importance: Cancer and other noncommunicable diseases (NCDs) are now widely recognized as a threat to global development. The latest United Nations high-level meeting on NCDs reaffirmed this observation and also highlighted the slow progress in meeting the 2011 Political Declaration on the Prevention and Control of Noncommunicable Diseases and the third Sustainable Development Goal. Lack of situational analyses, priority setting, and budgeting have been identified as major obstacles in achieving these goals. All of these have in common that they require information on the local cancer epidemiology. The Global Burden of Disease (GBD) study is uniquely poised to provide these crucial data. Objective: To describe cancer burden for 29 cancer groups in 195 countries from 1990 through 2017 to provide data needed for cancer control planning. Evidence Review: We used the GBD study estimation methods to describe cancer incidence, mortality, years lived with disability, years of life lost, and disability-Adjusted life-years (DALYs). Results are presented at the national level as well as by Socio-demographic Index (SDI), a composite indicator of income, educational attainment, and total fertility rate. We also analyzed the influence of the epidemiological vs the demographic transition on cancer incidence. Findings: In 2017, there were 24.5 million incident cancer cases worldwide (16.8 million without nonmelanoma skin cancer [NMSC]) and 9.6 million cancer deaths. The majority of cancer DALYs came from years of life lost (97%), and only 3% came from years lived with disability. The odds of developing cancer were the lowest in the low SDI quintile (1 in 7) and the highest in the high SDI quintile (1 in 2) for both sexes. In 2017, the most common incident cancers in men were NMSC (4.3 million incident cases); tracheal, bronchus, and lung (TBL) cancer (1.5 million incident cases); and prostate cancer (1.3 million incident cases). The most common causes of cancer deaths and DALYs for men were TBL cancer (1.3 million deaths and 28.4 million DALYs), liver cancer (572000 deaths and 15.2 million DALYs), and stomach cancer (542000 deaths and 12.2 million DALYs). For women in 2017, the most common incident cancers were NMSC (3.3 million incident cases), breast cancer (1.9 million incident cases), and colorectal cancer (819000 incident cases). The leading causes of cancer deaths and DALYs for women were breast cancer (601000 deaths and 17.4 million DALYs), TBL cancer (596000 deaths and 12.6 million DALYs), and colorectal cancer (414000 deaths and 8.3 million DALYs). Conclusions and Relevance: The national epidemiological profiles of cancer burden in the GBD study show large heterogeneities, which are a reflection of different exposures to risk factors, economic settings, lifestyles, and access to care and screening. The GBD study can be used by policy makers and other stakeholders to develop and improve national and local cancer control in order to achieve the global targets and improve equity in cancer care. © 2019 American Medical Association. All rights reserved.Peer reviewe