Asma Najibi - Academia.edu (original) (raw)

Papers by Asma Najibi

Clinical and Experimental Hepatology

Taurine (TAU) is a free amino acid abundant in the human body. Various physiological roles have b... more Taurine (TAU) is a free amino acid abundant in the human body. Various physiological roles have been attributed to TAU. At the subcellular level, mitochondria are the primary targets for TAU function. Meanwhile, it has been found that TAU depletion is associated with severe pathologies. Cholestasis is a severe clinical complication that can progress to liver fibrosis, cirrhosis, and hepatic failure. Bile duct ligation (BDL) is a reliable model for assessing cholestasis/cirrhosis and related complications. The current study was designed to investigate the effects of cholestasis/cirrhosis on tissue and mitochondrial TAU reservoirs. Cholestatic rats were monitored (14 and 42 days after BDL surgery), and TAU levels were assessed in various tissues and isolated mitochondria. There was a significant decrease in TAU in the brain, heart, liver, kidney, skeletal muscle, intestine, lung, testis, and ovary of the BDL animals (14 and 42 days after surgery). Mitochondrial levels of TAU were also significantly depleted in BDL animals. Tissue and mitochondrial TAU levels in cirrhotic animals (42 days after the BDL operation) were substantially lower than those in the cholestatic rats (14 days after BDL surgery). These data indicate an essential role for tissue and mitochondrial TAU in preventing organ injury induced by cholestasis/cirrhosis and could justify TAU supplementation for therapeutic purposes.

Pharmaceutical Sciences, 2020

Background: Cholestatic liver disease primarily affects hepatic tissue. Cholestasis could also in... more Background: Cholestatic liver disease primarily affects hepatic tissue. Cholestasis could also influence the function of other organs rather than the liver. Cholestasis-induced kidney injury is a severe clinical complication known as "cholemic nephropathy" (CN). Bile duct ligation (BDL) is a trustworthy experimental model for inducing CN. Although the precise mechanism of renal injury in cholestasis is not fully recognized, several studies revealed the role of oxidative stress in CN. There is no promising pharmacological intervention against CN. Carnosine (CAR) is a peptide extensively investigated for its pharmacological effects. Radical scavenging and antioxidative stress are major features of CAR. The current study aimed to evaluate the role of CAR supplementation on the CN. Methods: CAR was administered (250 and 500 mg/kg, i.p) to BDL rats for 14 consecutive days. Urine and serum markers of renal injury, biomarkers of oxidative stress in the kidney tissue, and renal hi...

Clinical and Experimental Hepatology, 2021

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

Xenobiotics-induced liver injury is a major challenge for clinicians and pharmaceutical industry.... more 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 sig...

Taurine (2-aminoethane sulfonic acid) is a non-protein amino acid found in high concentration in ... more 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...

Liver Research, 2020

Abstract Background and aim Cholestasis-associated renal injury or cholemic nephropathy (CN) is a... more Abstract Background and aim Cholestasis-associated renal injury or cholemic nephropathy (CN) is a serious clinical problem. Previous studies mentioned that oxidative stress and mitochondrial impairment play a role in CN. There is no specific pharmacological intervention for CN. Metformin is an anti-diabetic drug administered for decades. On the other hand, novel pharmacological properties have emerged for this drug. The effect of metformin on oxidative stress parameters has been well-recognized in different experimental models. It has also been found that metformin positively affected mitochondrial function. The current study aimed to evaluate the effects of metformin in an animal model of CN. Methods Rats underwent bile duct ligation (BDL) and were treated with metformin (250 and 500 mg/kg) for 14 consecutive days. Two weeks after the BDL operations, urine, serum, and kidney samples were collected and analyzed. Results Markers of oxidative stress, including reactive oxygen species (ROS) formation, lipid peroxidation, protein carbonylation, depleted antioxidant capacity, and decreased glutathione (GSH) levels were detected in BDL animals. Moreover, mitochondrial indices, including adenosine triphosphate (ATP) level, dehydrogenase activity, mitochondrial membrane potential, and mitochondrial permeability, were impaired in the kidney of cholestatic rats. Renal histopathological alterations in cholestatic animals included tubular degeneration and interstitial inflammation, cast formation, and fibrosis. It was found that metformin significantly alleviated oxidative stress and improved mitochondrial indices in the kidney of cholestatic rats. Tissue histopathological alterations were also mitigated in metformin-treated groups. Conclusions Metformin could be a candidate for managing CN. The nephroprotective role of metformin is primarily associated with its effects on oxidative stress parameters and mitochondrial function.

Biomedicine & Pharmacotherapy, 2019

Cholemic nephropathy (CN) is a clinical complication associated with cholestasis and chronic live... more Cholemic nephropathy (CN) is a clinical complication associated with cholestasis and chronic liver diseases. CN could lead to renal failure and the need for kidney transplantation if not appropriately managed. On the other hand, although the clinical features of CN are well described, there is no clear idea on the precise cellular and molecular mechanisms of CN. The current study was designed to evaluate kidney mitochondrial function in cholestasis-associated CN. Rats underwent bile duct ligation (BDL) surgery, and kidney mitochondria were isolated at scheduled time intervals (14, 28, and 42 days after BDL operation). Several mitochondrial indices including mitochondrial permeabilization and swelling, glutathione and ATP content, mitochondrial depolarization, and lipid peroxidation were evaluated. Renal tissue markers of oxidative stress along with tissue histopathological changes and serum biochemistry were also analyzed. Severe kidney tissue histopathological alterations including interstitial inflammation, necrosis, and Bowman capsule dilation were detected in the BDL animals. Moreover, drastic elevation in renal fibrosis and collagen deposition was detected in BDL rats. Oxidative stress markers were also significantly enhanced in the kidney tissue of BDL animals. On the other hand, it was found that mitochondrial indices of functionality were significantly deteriorated in BDL rats. These data introduce mitochondrial dysfunction and energy metabolism disturbances as a fundamental mechanism involved in the pathogenesis of bile acids-associated renal injury during cholestasis.

Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie, Jan 7, 2018

Betaine is a derivative of the amino acid glycine widely investigated for its hepatoprotective pr... more Betaine is a derivative of the amino acid glycine widely investigated for its hepatoprotective properties against alcoholism. The protective properties of betaine in different other experimental models also have been documented. On the other hand, the exact cellular mechanism of cytoprotection provided by betaine is obscure. The current study was designed to evaluate the hepatoprotective effects of betaine and its potential mechanisms of hepatoprotection in two animal models of acute and chronic liver injury. Bile duct ligation (BDL) was used as a model of chronic liver injury and thioacetamide (TAA)-induced hepatotoxicity was applied as the acute liver injury model. Severe increase in serum markers of liver tissue damage along with significant liver tissue histopathological changes were evident in both acute and chronic models of hepatic injury. It was also found that tissue markers of oxidative stress were significantly increased in BDL and TAA-treated animals. Moreover, liver mit...

Drug and chemical toxicology, Jan 3, 2018

Drug-induced liver injury is a major concern in clinical studies as well as in post-marketing sur... more Drug-induced liver injury is a major concern in clinical studies as well as in post-marketing surveillance. Previous evidence suggested that drug exposure during periods of inflammation could increase an individual's susceptibility to drug hepatoxicity. The antithyroid drugs, methimazole (MMI) and propylthiouracil (PTU) can cause adverse reactions in patients, with liver as a usual target. We tested the hypothesis that MMI and PTU could be rendered hepatotoxic in animals undergoing a modest inflammation. Mice were treated with a nonhepatotoxic dose of LPS (100 µg/kg, i.p) or its vehicle. Nonhepatotoxic doses of MMI (10, 25 and 50 mg/kg, oral) and PTU (10, 25 and 50 mg/kg, oral) were administered two hours after LPS treatment. It was found that liver injury was evident only in animals received both drug and LPS, as estimated by increases in serum alanine aminotransferase (ALT), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), and TNF-α. An increase in liver myeloper...

Renal failure, 2017

Sulfasalazine is a commonly used drug for the treatment of rheumatoid arthritis and inflammatory ... more Sulfasalazine is a commonly used drug for the treatment of rheumatoid arthritis and inflammatory bowel disease. There are several cases of renal injury encompass sulfasalazine administration in humans. The mechanism of sulfasalazine adverse effects toward kidneys is obscure. Oxidative stress and its consequences seem to play a role in the sulfasalazine-induced renal injury. The current investigation was designed to investigate the effect of sulfasalazine on kidney mitochondria. Rats received sulfasalazine (400 and 600 mg/kg/day, oral) for 14 consecutive days. Afterward, kidney mitochondria were isolated and assessed. Sulfasalazine-induced renal injury was biochemically evident by the increase in serum blood urea nitrogen (BUN), gamma-glutamyl transferase (γ-GT), and creatinine (Cr). Histopathological presentations of the kidney in sulfasalazine-treated animals revealed by interstitial inflammation, tubular atrophy, and tissue necrosis. Markers of oxidative stress including an increa...

The International Journal of Occupational and Environmental Medicine, 2015

Background: Hydrogen sulfide (H 2 S) exhibits both physiological and toxicological roles in the b... more Background: Hydrogen sulfide (H 2 S) exhibits both physiological and toxicological roles in the biological systems. Acute exposure to high levels of H 2 S is life threatening while longterm exposure to ambient levels of H 2 S elicits human health effects. Objective: To study the harmful effects of long-term exposure to low levels of H 2 S on human blood cells. Methods: 110 adult workers from Iran who were occupationally exposed to 0-90 ppb H 2 S for 1-30 years were studied. The participants aged between 18 and 60 years and were exposed directly or indirectly to sulfur compounds (exposed group). The origin of H 2 S was natural gas processing plants. A control group consisting of 110 males who were not in contact with H 2 S was also studied. For all participants, hematological profile including total hemoglobin and red blood cell count and sulfhemoglobin, methemoglobin levels were measured. Results: Among all parameters evaluated in this study the mean methemoglobin and sulfhemoglobin levels were significantly higher among workers who were exposed to sulfur compounds than the control group. Major differences throughout the study period for sulfhemoglobinemia among exposed groups were observed. Conclusion: Long-term exposure to even low levels of H 2 S in workplaces may have potential harmful effects on human health.

Clinics and research in hepatology and gastroenterology, Jan 7, 2017

Chronic liver injury and cirrhosis leads to liver failure. Hyperammonemia is a deleterious conseq... more Chronic liver injury and cirrhosis leads to liver failure. Hyperammonemia is a deleterious consequence of liver failure. On the other hand, oxidative stress seems to play a pivotal role in the pathogenesis of liver fibrosis as well as in the cytotoxic mechanism of ammonia. There is no promising therapeutic agent against ammonia-induced complications. The present study was conducted to evaluate the role of carnosine (CA) administration on liver pathological changes, elevated plasma ammonia, and its consequent events in cirrhotic rats. Bile duct ligated (BDL) rats were used as a model of cirrhosis. CA (250, 500, and 1000mg/kg, daily, i.p) was administered for 28 consecutive days to BDL animals. At the end of treatments, markers of oxidative stress and liver fibrosis was determined in liver and serum biomarkers of liver injury and plasma ammonia was assessed. Moreover, changes in animals' locomotor activity were monitored. Severe bridging fibrosis, inflammation, and necrosis in liv...

Advanced Pharmaceutical Bulletin, 2016

Accumulating evidence suggests that drug exposure during a modest inflammation induced by bacteri... more Accumulating evidence suggests that drug exposure during a modest inflammation induced by bacterial lipopolysaccharide (LPS) might increase the risk of drug-induced liver injury. The current investigation was designed to test if antimalarial drugs hepatotoxicity is augmented in LPS-treated animals. Methods: Rats were pre-treated with LPS (100 µg/kg, i.p). Afterward, non-hepatotoxic doses of amodiaquine (25, 50 and 100 mg/kg, oral) and chloroquine (25, 50 and 100 mg/kg, oral) were administered. Results: Interestingly, liver injury was evident only in animals treated with both drug and LPS as estimated by pathological changes in serum biochemistry (ALT, AST, LDH, and TNF-α), and liver tissue (severe hepatitis, endotheliitis, and sinusoidal congestion). An increase in liver myeloperoxidase enzyme activity, lipid peroxidation, and protein carbonylation, along with tissue glutathione depletion were also detected in LPS and drug co-treated animals. Conclusion: Antimalarial drugs rendered hepatotoxic in animals undergoing a modest inflammation. These results indicate a synergistic liver injury from co-exposure to antimalarial drugs and inflammation.

Biomedicine & Pharmacotherapy, 2017

Ammonia-induced mitochondrial dysfunction and energy crisis is known as a critical consequence of... more Ammonia-induced mitochondrial dysfunction and energy crisis is known as a critical consequence of hepatic encephalopathy (HE). Hence, mitochondria are potential targets of therapy in HE. The current investigation was designed to evaluate the role of taurine treatment on the brain and liver mitochondrial function in a rat model of hepatic encephalopathy and hyperammonemia. The animals received thioacetamide (400 mg/kg, i.p, for three consecutive days at 24-h intervals) as a model of acute liver failure and hyperammonemia. Several biochemical parameters were investigated in the serum, while the animals' cognitive function and locomotor activity were monitored. Mitochondria was isolated from the rats' brain and liver and several indices were assessed in isolated mitochondria. Liver failure led to cognitive dysfunction and impairment in locomotor activity in the rats. Plasma and brain ammonia was high and serum markers of liver injury were drastically elevated in the thioacetamide-treated group. An assessment of brain and liver mitochondrial function in the thioacetamide-treated animals revealed an inhibition of succinate dehydrogenase activity (SDA), collapsed mitochondrial membrane potential, mitochondrial swelling, and increased reactive oxygen species (ROS). Furthermore, a significant decrease in mitochondrial ATP was detected in the brain and liver mitochondria isolated from thioacetamidetreated animals. Taurine treatment (250, 500, and 1000 mg/kg) decreased mitochondrial swelling, ROS, and LPO. Moreover, the administration of this amino acid restored brain and liver mitochondrial ATP. These data suggest taurine to be a potential protective agent with therapeutic capability against hepatic encephalopathy and hyperammonemia-induced mitochondrial dysfunction and energy crisis.

Pharmaceutical Sciences, 2016

Toxicology Letters, 2016

Methimazole is the most frequently prescribed antithyroid agent. On the other hand, several cases... more Methimazole is the most frequently prescribed antithyroid agent. On the other hand, several cases of liver injury are attributed to this drug. The mechanism of methimazole-induced liver injury is obscure. Hepatocytes mitochondria seem to be a target for methimazole cytotoxicity. Current investigation aimed to evaluate the effects of methimazole on the hepatocytes mitochondria in different experimental models. In the in vivo model, methimazole (100, 200 and 400mg/kg, i.p) was administered to mice and liver mitochondria were isolated and assessed. In the in vitro experiments, intact isolated liver mitochondria were incubated with increasing methimazole concentrations (10μM-100mM). It was found that methimazole decreased liver mitochondrial ATP and glutathione, increased mitochondrial swelling, lipid peroxidation and reactive oxygen species (ROS), and collapsed mitochondrial membrane potential when administered to mice. Paradoxically, methimazole not only caused no significant injury toward isolated liver mitochondria in vitro but improved mitochondrial function and protected this organelle. The differences between two investigated models in the current study might be associated with drug bioactivation and reactive metabolites formation. These findings suggest mitochondrial dysfunction as a mechanism for methimazole-induced liver injury. Moreover, methimazole seems to be a novel mitochondrial protecting agent in vitro.

BioImpacts, 2016

Introduction: Sulfasalazine is a drug commonly administrated against inflammatory-based disorders... more Introduction: Sulfasalazine is a drug commonly administrated against inflammatory-based disorders. On the other hand, kidney and liver injury are serious adverse events accompanied by sulfasalazine administration. No specific therapeutic option is available against this complication. The current investigation was designed to evaluate the potential protective effects of taurine against sulfasalazine-induced kidney and liver injury in rats. Methods: Male Sprague-Dawley rats were administered with sulfasalazine (600 mg/kg, oral) for 14 consecutive days. Animals received different doses of taurine (250, 500 and 1000 mg/ kg, i.p.) every day. Markers of organ injury were evaluated on day 15 th , 24 h after the last dose of sulfasalazine. Results: Sulfasalazine caused renal and hepatic injury as judged by an increase in serum level of creatinine (Cr), alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP). The levels of reactive oxygen species (ROS) and lipid peroxidation were raised in kidney and liver of sulfasalazine-treated animals. Moreover, tissue glutathione reservoirs were depleted after sulfasalazine administration. Histopathological changes of kidney and liver also endorsed organ injury. Taurine administration (250, 500 and 1000 mg/kg/day, i.p) alleviated sulfasalazine-induced renal and hepatic damage. Conclusion: Taurine administration could serve as a potential protective agent with therapeutic capabilities against sulfasalazine adverse effects.

Journal of Coloproctology, 2016

Objective To investigate the effects of hydroalcoholic extract of Ziziphus jujuba on the histopat... more Objective To investigate the effects of hydroalcoholic extract of Ziziphus jujuba on the histopathological, tissue oxidative stress and inflammation plus to antioxidant pathways of colon tissue in rat with induced Ulcerative colitis. Materials and methods Ulcerative colitis was induced in 80 rats those divided into 8 equal groups. Group 1 and 2 were negative controls receiving 1 mL/day of normal saline in enema and oral; group 3 and 4 as positive control 1 and 2 received 10 mg/kg of intra-colonic asacol and oral mesalazine; groups 5 and 6 received 20% and 40% of hydroalcoholic extract of Z. jujuba trans-rectally; group 7 and 8 received 1500 and 3000 mg/kg of hydroalcoholic extract of Z. jujuba orally, respectively. After 7 days, animals were evaluated for colon tissue histopathology, levels of malondialdehyde and IL-1β, and activities of superoxide dismutase, glutathione peroxidase and myeloperoxidase in colon tissue. Results Hydroalcoholic extract of Z. jujuba in both forms of tran...

Toxicological Research, 2016

Saudi Journal of Gastroenterology, 2016

Background/Aim: Ulcerative colitis (UC) is a type of chronic inflammatory bowel disease with unkn... more Background/Aim: Ulcerative colitis (UC) is a type of chronic inflammatory bowel disease with unknown etiology. Several therapeutic strategies such as consumption of medicinal plants have been used for its treatment. The aim of this study was to evaluate healing effects of Calendula officinalis hydroalcoholic extract in experimentally induced UC in rat. Materials and Methods: Ninety-six rats, weighing 200 ± 20 g, were randomly divided into eight equal groups. UC induced by 3% acetic acid and oral doses of C. officinalis extract, 1500 and 3000 mg/kg, and enema (gel 10% and 20%) were given. Two groups as positive controls were given asacol (enema) and oral mesalamine. Negative control groups were given normal saline and base gel. On days 3 and 7, intestinal histopathology and weight changes, plus oxidative stress indices including malondialdehyde (MDA) level and myeloperoxidase (MPO) activity were assayed. Results: A significant increase in the body weight of rats was seen in the group given C. officinalis extract 3000 mg/kg orally, oral mesalamine, and 20% intracolonic gel form of marigold extract compared with negative control and base gel groups during the experimental period. Acute inflammation and granular atrophy after UC induction were resolved completely completely by both 20% intracolonic gel and 3000 mg/ kg orally. An increase in MPO activity and a decrease in MDA level in response to oral and intracolonic gel form of C. officinalis were observed 3 and and 7 days after treatment (P < 0.05). Conclusion: Our results indicate that oral and enema forms of hydroalcoholic extract of C. officinalis can be offered as are potential therapeutic agents for UC induced in rats.