Inorganic osmolytes and enzymatic biomarkers from the manabi oyster (Crassostrea cf. corteziensis) in response to saline stress

Abrupt drops in salinity that occur in tropical estuaries during the equatorial rainy season led to hyposaline conditions which may reduce the populational density of oysters. To assess the effect of saline stress on physiological and metabolic responses of the Manabi oyster (Crassostrea cf. corteziensis) was exposed to 35, 30, 20,10 and 5‰ concentrations during 96 h. Inorganic osmolytes, pH, salinity, haemocyanin and protein concentration in the plasma as well as the number of oysters with closed valves were recorded. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and catalase (CAT) activity were analysed. Inorganic osmolytes and internal salinity were elevated in oysters exposed to 35, 10 and 5‰. A significant number of oysters with valve closure was observed in 10 and 5‰, which coincided with a decline in physiological pH and changes in haemocyanin concentrations. AST activity and AST/ALT ratio were reduced under 35, 10 and 5‰, and CAT increased in oysters exposed to 35‰; but protein concentration, LDH and ALP did not show significant variations. Metabolic adjustment and behavior of the Manabi oyster could explain tolerance and survival (at least for a short term) to hyposaline stress in tropical estuarine ecosystems.

Predictive factors to estimate the severity of nonalcoholic fatty liver disease in candidates for Roux-en-Y gastric bypass

OBJECTIVES

Non-alcoholic fatty liver disease (NAFLD) is related to obesity, insulin resistance, dyslipidemia, and metabolic syndrome. The increasing prevalence of NAFLD results in a significant number of patients manifesting chronic liver disease over time. The aim of this study was to analyze the predictive factors to estimate NAFLD severity in patients who are candidates for Roux-en-Y gastric bypass.

METHODS

This descriptive observational study was conducted with 136 obese patients who were candidates for Roux-en-Y gastric bypass and had mild, moderate, or severe NAFLD.

RESULTS

Severe NAFLD was more prevalent among the men (P = 0.007), and mild NAFLD was more prevalent among the women (P = 0.007). Hyperferritinemia was observed in the group with severe NAFLD (P = 0.01). Neck circumference and waist-to-height ratio were associated with an increased risk when comparing the groups with mild and severe NAFLD and those with moderate and severe NAFLD (P = 0.023 and P = 0.001, respectively); the alanine aminotransferase (ALT) and aspartate aminotransferase ratio values were >1 (P = 0.002) in the same comparisons. The regression analyses showed that an increase of 1 ng/mL in vitamin D reduced the chances of severe steatosis by 10% (P = 0.043), and an increase of 1 U/L ALT increased the chances of severe steatosis by 13% (P = 0.002).

CONCLUSION

High neck circumference and low waist-to-height ratio values, male sex, hyperferritinemia, increased serum ALT values, and decreased vitamin D levels were related to the risk for severe NAFLD.

The effects of zinc supplementation on the metabolic factors in patients with non-alcoholic fatty liver disease: a randomized, double-blinded, placebo-controlled clinical trial

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is associated with metabolic factors including obesity, dyslipidemia, insulin resistance, oxidative stress, and elevated inflammatory factors. Zinc (Zn) supplementation has been investigated as a potential adjunctive therapy in managing NAFLD outcomes.

METHODS

In this randomized, double-blinded, controlled clinical trial, 50 overweight or obese participants with NAFLD were randomized into 2 groups of 25 and received either 30 mg of daily Zn or a placebo for 8 weeks. Both groups were invited to follow a balanced energy-restricted diet and physical activity recommendations.

RESULTS

Based on the between-group comparison, Zn supplementation caused a significant increase in the Zn level (P < 0.001) and a significant decrease in weight (P = 0.004), body mass index (BMI) (P = 0.002), waist circumference (P = 0.010), aspartate transaminase (AST) (P = 0.033), total cholesterol (TC) (P = 0.045), and low-density lipoprotein cholesterol (LDL-C) (P = 0.014), but it had no significant effect on alanine transaminase (ALT), fasting blood sugar (FBS), insulin, homeostasis model assessment of insulin resistance (HOMA-IR), high-density lipoprotein (HDL), triglyceride (TG), high-sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA), and total antioxidant capacity (TAC) (P > 0.05).

CONCLUSION

The results of the present study indicated that 8-week supplementation of 30 mg daily Zn may increase the Zn serum level and decline anthropometric parameters, AST, TC, and LDL-C in NAFLD patients, so further research is suggested in the future.

TRIAL REGISTRATION

The trial was retrospectively registered at IRCT.ir as IRCT20191015045113N1 (December/8/2019).

Impact of Liver Functions by Repurposed Drugs for COVID-19 Treatment

Liver injury is an important complication that may arise in patients suffering from coronavirus disease 2019 (COVID-19) and is accompanied by a transient increase of transaminases and/or other liver enzymes. Liver function test (LFT) abnormalities generally disappear when the COVID-19 resolves or hepatotoxic drugs are discontinued. The LFT abnormalities are associated with drug-induced liver injury (DILI), due to the overuse of antimalarials, antivirals, and antimicrobials. Studies have reported varying levels of these liver injuries in COVID-19 patients; however, most involve elevated serum aminotransferases. Hepatic dysfunction is significantly high in patients with severe illness and has poor outcome. Normally, the liver is involved in the metabolism of many drugs, including nucleoside analogs and protease inhibitors, which are currently repurposed to treat COVID-19. In addition to the manifestation of COVID-19, drugs implemented in its treatment may aggravate liver injuries. Thus, DILI should be considered especially in those COVID-19 patients with underlying liver disease. It was unclear whether the elevated liver enzymes have originated from the underlying disease or DILI in this population. Furthermore, it is difficult to establish a direct relationship between a specific drug and liver injury. Another possible effect of liver damage may due to inflammatory cytokine storm in severe COVID-19. Liver injury can change metabolism, excretion, dosing, and expected concentrations of the drugs, which may make it difficult to achieve a therapeutic dose of the drug or increase the risk of adverse effects. These repurposed drugs have shown limited efficacy against the virus and the disease itself; however, they still pose risk of adverse effects. Careful and close monitoring of LFTs in COVID-19 patients can provide early diagnosis of liver injury, and the risk of DILI could be reduced. Also, drug interactions in liver-transplanted patients should always be kept in mind for certain immunosuppressive therapies and their known signs of DILI. Altogether, abnormal LFTs should not be regarded as a contraindication to use COVID-19 experimental therapies if needed under emergent status.

Human cytosolic transaminases: side activities and patterns of discrimination towards physiologically available alternative substrates

Transaminases play key roles in central metabolism, transferring the amino group from a donor substrate to an acceptor. These enzymes can often act, with low efficiency, on compounds different from the preferred substrates. To understand what might have shaped the substrate specificity of this class of enzymes, we examined the reactivity of six human cytosolic transaminases towards amino acids whose main degradative pathways do not include any transamination. We also tested whether sugars and sugar phosphates could serve as alternative amino group acceptors for these cytosolic enzymes. Each of the six aminotransferases reacted appreciably with at least three of the alternative amino acid substrates in vitro, albeit at usually feeble rates. Reactions with L-Thr, L-Arg, L-Lys and L-Asn were consistently very slow-a bias explained in part by the structural differences between these amino acids and the preferred substrates of the transaminases. On the other hand, L-His and L-Trp reacted more efficiently, particularly with GTK (glutamine transaminase K; also known as KYAT1). This points towards a role of GTK in the salvage of L-Trp (in cooperation with ω-amidase and possibly with the cytosolic malate dehydrogenase, MDH1, which efficiently reduced the product of L-Trp transamination). Finally, the transaminases were extremely ineffective at utilizing sugars and sugar derivatives, with the exception of the glycolytic intermediate dihydroxyacetone phosphate, which was slowly but appreciably transaminated by some of the enzymes to yield serinol phosphate. Evidence for the formation of this compound in a human cell line was also obtained. We discuss the biological and evolutionary implications of our results.

Longitudinal progression of clinical variables associated with graded liver injury in COVID-19 patients

Background

Hospital-acquired liver injury is associated with worse outcomes in COVID-19. This study investigated the temporal progression of clinical variables of in-hospital liver injury in COVID-19 patients.

Methods

COVID-19 patients (n = 1361) were divided into no, mild and severe liver injury (nLI, mLI and sLI) groups. Time courses of laboratory variables were time-locked to liver-injury onset defined by alanine aminotransferase level. Predictors of liver injury were identified using logistic regression.

Results

The prevalence of mLI was 39.4% and sLI was 9.2%. Patients with escalated care had higher prevalence of sLI (23.2% vs. 5.0%, p < 0.05). sLI developed 9.4 days after hospitalization. sLI group used more invasive ventilation, anticoagulants, steroids, and dialysis (p < 0.05). sLI, but not mLI, had higher adjusted mortality odds ratio (= 1.37 [95% CI 1.10, 1.70], p = 0.005). Time courses of the clinical variables of the sLI group differed from those of the nLI and mLI group. In the sLI group, alanine aminotransferase, procalcitonin, ferritin, and lactate dehydrogenase showed similar temporal profiles, whereas white-blood-cell count, D-dimer, C-reactive protein, respiration and heart rate were elevated early on, and lymphocyte and SpO2 were lower early on. The top predictors of sLI were alanine aminotransferase, lactate dehydrogenase, respiration rate, ferritin, and lymphocyte, yielding an AUC of 0.98, 0.92, 0.88 and 0.84 at 0, − 1, − 2 and − 3 days prior to onset, respectively.

Conclusions

This study identified key clinical variables predictive of liver injury in COVID-19, which may prove useful for management of liver injury. Late onset of sLI and more aggressive care are suggestive of treatment-related hepatotoxicity.

Dietary flaxseed's protective effects on body tissues of mice after oral exposure to xylene

Xylene is a common pollutant in the environment that enters the body of animals and humans in various ways, but most often through the respiratory tract and adversely affects their overall health. However, xylene effects after oral exposure have not been sufficiently studied. This study aimed to investigate the effects of xylene exposure on the mouse organism and to identify possible beneficial effects of flaxseed on such exposure. Eighty mice were divided into four groups: control group C (basal diet + no xylene exposure), group X (oral exposure by 400 mg/kg/day xylene), group F (10% flaxseed supplementation of basal diet), and group XF (10% dietary flaxseed + oral exposure by xylene). Experimental trial took 14 days. Clinical examination, spectroscopic analysis of tissue aminotransferases, total lactate dehydrogenase (TLDH), and acetylcholinesterase (AchE) activities, electrophoretic analysis of LDH isoenzymes, western blot and immunohistochemical analysis of apoptosis as well as routine histology of the kidneys and jejunum, and transmission electron microscopy of the liver were performed. Marked restlessness in group X and high weight losses in mice of all groups were recorded during the experiment. Xylene promoted apoptosis (caspase-3 expression) without causing marked structural changes in the liver and jejunum, although renal cortex structure was affected adversely. In the brain, liver, and kidney of mice, xylene increased levels of liver transaminases, LDH, and decreased AchE activities, reflecting cell membrane damage. Flaxseed feeding improved animal behaviour, leakage of enzymes and prevented selected tissue toxic damage induced by xylene by protecting cell membrane integrity and fluidity and by suppressing apoptosis. These results point at the protective effect of flaxseed consumption on mice.

Liver injury predicts overall mortality in severe COVID-19: a prospective multicenter study in Brazil

Background/purpose

The relationship between liver injury and mortality remains unclear in patients with COVID-19. We aimed to evaluate the prognostic value of aminotransferases levels at hospital admission to predict mortality in patients with COVID-19.

Methods and results

This prospective study included 406 patients [57% male, aged 56 years] with COVID-19 hospitalized in 26 centers in Brazil. Overall, 36.7% (95% CI 32.1–41.5) presented at admission with severe disease requiring respiratory support. The prevalence of elevated ALT and AST levels at admission [> 2 × ULN] was 14.0% (95% CI 11.0–17.8) and 12.9% (95% CI 10.0–16.6), respectively. Sixty-two patients [15.3% (95% CI 12.1–19.1)] died during hospitalization and the overall mortality rate was 13.4 (10.5–17.2) deaths per 1000 persons-years. The 15-day-overall survival (95% CI) was significantly lower in patients with ALT levels ≥ 2 × ULN compared to those with ALT < 2 × ULN [67.1% (48.4–80.2) vs 83.4% (76.1–88.6), p = 0.001] and in those with AST levels ≥ 2 × ULN compared to those with AST < 2 × ULN [61.5% (44.7–74.6) vs 84.2% (76.5–89.5), p < 0.001]. The presence of elevated aminotransferases levels at hospital admission significantly increased the risk of in-hospital all-cause mortality adjusted for age-and-sex. Those findings were present in the subgroup of critically ill patients already admitted in need of respiratory support (n = 149), but not in patients without that requirement at admission (n = 257).

Conclusions

Elevated aminotransferases at hospital admission predicted in-hospital all-cause mortality in patients with COVID-19, especially in those with severe disease. Measurement of transaminases levels at hospital admission should be integrated to the care of patients with COVID-19 as an auxiliary strategy to identify patients at higher death risk.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12072-021-10141-6.

Body Building and Aminotransferase Elevations: A Review

In addition to liver injury, elevation of aminotransferases can be caused by strenuous exercise and use of muscle-building and weight-loss supplements. The purpose of this review is to discuss the various mechanisms of elevation of aminotransferases related to body building. A literature review was performed on clinical trials and case reports involving exercise or supplement use and their effects on aminotransferases. Normal aminotransferase levels varied according to gender, age, body mass index, and comorbidities. Strenuous exercise and weight lifting, especially in the unaccustomed, can cause elevated aminotransferases in the absence of liver damage. Supplements such as anabolic steroids, ephedra, and LipoKinetix, amongst others, have also been associated with aminotransferase elevations. The pattern of elevation of aminotransferases is not helpful in distinguishing liver from muscle injury. Other associated muscle enzymes can be useful in making that distinction. To prevent aminotransferase elevations, subjects not accustomed to moderate-high intensity workouts, are recommended to undertake gradual increase in intensity. When causes of liver injury have been ruled out, investigation into bodybuilding, extreme exercise, and supplement use is warranted.

Abnormal liver function tests associated with severe rhabdomyolysis

Rhabdomyolysis is a syndrome of skeletal muscle injury with release of cellular constituents such as potassium, phosphate, urate and intracellular proteins such as myoglobin into the circulation, which may cause complications including acute kidney injury, electrolyte disturbance and cardiac instability. Abnormal liver function tests are frequently observed in cases of severe rhabdomyolysis. Typically, there is an increase in serum aminotransferases, namely aspartate aminotransferase and alanine aminotransferase. This raises the question of liver injury and often triggers a pathway of investigation which may lead to a liver biopsy. However, muscle can also be a source of the increased aminotransferase activity. This review discusses the dilemma of finding abnormal liver function tests in the setting of muscle injury and the potential implications of such an association. It delves into some of the clinical and experimental evidence for correlating muscle injury to raised aminotransferases, and discusses pathophysiological mechanisms such as oxidative stress which may cause actual liver injury. Serum aminotransferases lack tissue specificity to allow clinicians to distinguish primary liver injury from muscle injury. This review also explores potential approaches to improve the accuracy of our diagnostic tools, so that excessive or unnecessary liver investigations can be avoided.

Elevated serum levels of aminotransferases in relation to unhealthy foods intake: Tehran lipid and glucose study

BACKGROUND

Abnormal levels of liver enzymes, particularly aminotransferases, are prognostic features of non-alcoholic fatty liver disease (NAFLD). Considering the important role of dietary intakes in development of NAFLD, we aimed to determine possible association of unhealthy foods (fast foods, soft drinks, sweet and salty snacks) consumption with elevated levels of aminotransferases.

METHODS

This cross-sectional study was conducted within the framework of sixth phase of the Tehran Lipid and Glucose Study (2014-2017), on 187 adult men and 249 adult women (19-70 y). Usual intakes of unhealthy foods (kcal/week) were measured using a validated semi-quantitative 147-items food frequency questionnaire. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) were measured. Multivariable logistic regression models were used to estimate the odds of elevated aminotransferases in each tertile of energy-dense unhealthy foods.

RESULTS

Mean age of participants was 44.44 ± 15.09 years, 43% of participants were men. Higher consumption of fast foods (> 11.39% kcal/week) was associated with elevated ALT to AST ratio (OR: 3.27; 95% CI: 1.90-5.63) and elevated ALT (OR: 2.74; 95% CI: 1.57-4.76). Also, each 1 SD increased energy intakes from fast foods was related to increased chance of having elevated ALT and ALT to AST ratio by 35% (OR: 1.35; 95% CI: 1.08-1.68, OR: 1.35; 95% CI: 1.10-1.66, respectively). There was no significant association between consumption of soft drinks, sweet or salty snacks and elevated aminotransferases.

CONCLUSIONS

Higher intakes of energy from fast foods seems to be associated with an elevated serum levels of ALT and ALT to AST ratio, as indicators of development of NAFLD.

(3Z)-5-Chloro-3-(Hydroxyimino)indolin-2-one attenuates hyperglycemia, increased hepatic glycogen content and hepatic damage induced by malathion acute exposure in rats

BACKGROUND

Organophosphorus pesticides (OP's) are heavily constituted in agriculture, gardens, home and veterinary and although it is useful, there are concerns about the environment, safety and health of human and animals. In this study, we investigated the effects of a new oxime, (3Z)-5-Chloro-3-(Hydroxyimino)indolin-2-one (OXIME) against the alterations induced by malathion, an OP insecticide, acute exposure on markers of hepatic damage, glucose homeostasis, oxidative stress in rats cholinesterase (ChE) activity in rats.

METHODS

Adult male Wistar rats were divided into four groups: Control; Malathion; OXIME; and Malathion+OXIME. Twelve hours after co-treatment with malathion (250 mg/kg, i.p.) and/or OXIME (50 mg/kg, i.g.), the plasma and liver samples were collected for biochemical analyses.

RESULTS

The OXIME blocked the increase of plasma markers of hepatic function (AST and ALP) and the enzymatic inhibition of catalase and glutathione reductase in the liver of malathion-treated rats. Moreover, the hepatic cholinesterases inhibition induced by malathion acute exposure was suppressed by OXIME treatment. As assessed, a single dose of OXIME lowered the glycemia levels and hepatic glycogen content enhanced by malathion.

CONCLUSIONS

This study suggests promise effects of (3Z)-5-Chloro-3-(Hydroxyimino) indolin-2-one against the hyperglycemia and the hepatic damage induced by malathion acute exposure, as well as its use as a ChE activity reactivator.

Thymoquinone, an Active Constituent of Black Seed Attenuates CCl4 Induced Liver Injury in Mice via Modulation of Antioxidant Enzymes, PTEN, P53 and VEGF Protein

AIM:

The present study was undertaken to evaluate the possible protective role of thymoquinone on CCl4-induced hepatotoxicity.

METHODS:

The activities of liver function enzymes and antioxidant enzymes were measured. Haematoxylin-Eosin staining was performed to analyze the live tissue alterations. Additionally, expression pattern of different proteins was evaluated through immunohistochemistry staining.

RESULTS:

The antioxidants enzymes activities were decreased significantly in the CCl4 induced group whereas recovery/increase of antioxidant enzymes was observed when thymoquinone was given to the mice. Moreover, thymoquinone administration significantly decrease the serum levels of alanine aminotransferase (ALT), alkaline phosphatase (ALP), and serum aspartate aminotransferase (AST). Liver tissue alterations were noted in CCl4 treated group whereas treatment with thymoquinone significantly prevented the CCl4-induced histological alteration. The expression of PTEN protein was high in CCl4 plus thymoquinone treated group while the loss of PTEN protein expression was observed in CCl4 treated group. Moreover, high expression of P53 protein was noticed in CCl4 treated the group as compared to CCl4 plus thymoquinone group. Difference in expression pattern of PTEN and p53 protein in CCl4 group and thymoquinone plus CCl4 treated group was statically significant (p < 0.05). Besides, expression of VEGF was high in CCl4 treated group as well as thymoquinone plus CCl4 treated group and difference in expression pattern was statically insignificant (p > 0.05).

CONCLUSION:

Our results suggest that thymoquinone can protect CCl4 induced liver damage and could be a preventive drug in the development of novel therapeutic agents for liver diseases.

Association between continuous positive airway pressure and serum aminotransferases in patients with obstructive sleep apnea

INTRODUCTION

Obstructive sleep apnea (OSA) has been suggested to be a potential contributing factor for nonalcoholic fatty liver disease (NAFLD). Studies on the association between continuous positive airway pressure (CPAP) and NAFLD in OSA patients are limited and controversial.

OBJECTIVES

The aim of this study was to assess the relationship between OSA and NAFLD and the effect of CPAP therapy on serum aminotransferase levels in OSA patients.

METHODS

A total of 160 consecutive patients who underwent standard polysomnography were enrolled. Blood samples were obtained in the morning after sleep for biological profile measurements. Non-invasive ultrasound techniques were used to assess liver steatosis and fibrosis. Within the OSA group, serum aminotransferases were detected before and after CPAP treatment.

RESULTS

Alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase, and liver steatosis score increased significantly with an increase in OSA severity. Stepwise multiple regression with liver steatosis score, ALT, AST as dependent variable, respectively, apnea-hypopnea index (β = 0.447, p = 0.020; β = 0.266, p = 0.001; β = 0.351, p = 0.020, respectively) significantly predicted the liver steatosis score, ALT, AST after adjustment for confounders. After 3 months of CPAP treatment, there was a significant decrease in both ALT (54.20 ± 24.34 vs. 46.52 ± 24.95, p = 0.000) and AST (31.82 ± 8.91 vs. 29.00 ± 8.34, p = 0.039).

CONCLUSIONS

OSA severity was independently associated with liver steatosis and elevation of serum aminotransferases. 3 months of CPAP therapy were associated with a statistically significant improvement on liver injury in OSA patients.

Versatility of putative aromatic aminotransferases from Candida albicans

Amino acids constitute the key sources of nitrogen for growth of Candida albicans. In order to survive inside the host in different and rapidly changing environments, this fungus must be able to adapt via its expression of genes for amino acid metabolism. We analysed the ARO8, ARO9, YER152C, and BNA3 genes with regards to their role in the nutritional flexibility of C. albicans. CaAro8p is undoubtedly the most versatile enzyme among the aminotransferases investigated. It is involved in the catabolism of histidine, lysine, and aromatic amino acids as well as in l-Lys, Phe and Tyr biosynthesis. CaAro9p participates in the catabolism of aromatic amino acids and lysine at high concentrations of these compounds, with no biosynthetic role. Conversely, the CaYer152Cp catalytic potential for aromatic amino acid catabolism observed in vitro appears to be of little importance in vivo. Neither biosynthetic nor catabolic roles of CaBan3p were observed for any proteinogenic amino acid. Finally, none of the analysed aminotransferases was solely responsible for the catabolism of a single particular amino acid or its biosynthesis.

Hepatic Complications of Anorexia Nervosa

Anorexia nervosa (AN) has the highest mortality rate of all psychiatric illnesses due to the widespread organ dysfunction caused by the underlying severe malnutrition. Starvation causes hepatocyte injury and death leading to a rise in aminotransferases. Malnutrition-induced hepatitis is common among individuals with AN especially as body mass index decreases. Acute liver failure associated with coagulopathy and encephalopathy can rarely occur. Liver enzymes may also less commonly increase as part of the refeeding process due to hepatic steatosis and can be distinguished from starvation hepatitis by the finding of a fatty liver on ultrasonography. Individuals with AN and starvation-induced hepatitis are at increased risk of hypoglycemia due to depleted glycogen stores and impaired gluconeogenesis. Gastroenterology and hepatology consultations are often requested when patients with AN and signs of hepatitis are hospitalized. It should be noted that additional laboratory testing, imaging, or liver biopsy all have low diagnostic yield, are costly, and potentially invasive, therefore, not generally recommended for diagnostic purposes. While the hepatitis of AN can reach severe levels, a supervised increase in caloric intake and a return to a healthy body weight often quickly lead to normalization of elevated aminotransferases caused by starvation.

Therapeutic benefits of green tea extract on various parameters in non-alcoholic fatty liver disease patients

BACKGROUND AND OBJECTIVE

NAFLD affecting up to 30% of the population globally. Drug treatment options are limited with disappointing results. The dietary supplementation in the form of green tea is another option. Our objective was toinvestigate the effect of Green tea extract (GTE) supplementation on various parameters innon-alcoholicfatty liver disease (NAFLD) patients.

METHODS

This study was conducted Dept. of Medicineof Sheikh Zayed Medical College/Hospital, Rahim Yar Khan from 15 April 2016 to 15 July 2016. Eighty overweight, non diabeticand dyslipidemic patients of NAFLD, diagnosed on the basis of ultrasound and aminotransferases level were randomized for treatmentwith capsule GTE500mg (n=40)and capsule placebo (n=40) twice a day for twelve weeks. Anthropometric parameters, liver enzymes, inflammatory markers and liver ultrasound imaging were estimated by SPSS-16 pre and post treatment.

RESULTS

As compared to placebo, GTE caused a significant improvement in body weight (29.5±3.8 to 27.2±3.2 kg/m2 p=0.03), BMI (86±10.5 to 80±12.4 kg p=0.026), HOMA-IR(4.32±2.25 to 3.16± 1.6 p=0.0081) lipid profile (i.e. TC: L242.5±20.5 to 215.4±18.6 mg/dl p=0.005; TG: 175±22.6 to145±18 mg/dlp=0.003; LDL-C:155±12.5 to 140±16.7 mg/dl p=0.011; HDL-C: 36.8±6.7 to46.4±5.8 mg/dl p =0.001, Aminotransferases (i.e. ALT: 70.4±15.8to52.8±12.2 IU/L p=0.04; AST: 65.8±12.4 to 44.3± 8.5U/L p =0.002) and Inflammatory markers (hs-CRP: 3.14±0.58 to 2.18±0.32 p =0.023 Adiponectin: 8.46±1.02 to 10.55±3.42μg/ml p =0.003)GTE also caused a 67.5% regression of fatty liver changes on ultrasound as compared to placebo which is 25%only.

CONCLUSION

GTEtherapy resulted in significant improvement in metabolic, chemical, inflammatory and radiological parameters of non-alcoholic fatty liver disease patients who were non-diabetic anddyslipidemic.

Nonalcoholic fatty liver disease in patients with acute ischemic stroke is associated with more severe stroke and worse outcome

BACKGROUND

There is a paucity of data regarding the association between nonalcoholic fatty liver disease (NAFLD) and acute ischemic stroke. Stroke is largely preventable, so that knowledge of risk factors is essential to achieve reductions in the stroke rate and resulting disease burden.

OBJECTIVE

The aim of the present study was to evaluate the prognostic value of NAFLD on stroke severity and outcome.

METHODS

We prospectively studied 200 patients who were admitted with acute ischemic stroke between September 2013 and August 2015. Demographic and vascular risk factors were detailed for all subjects. The severity of stroke was assessed with National Institutes of Health Stroke Scale score at admission. NAFLD was defined as serum alanine aminotransferase and/or aspartate aminotransferase levels above the upper limit of normal in the absence of other causes of elevated aminotransferase levels. The outcome was assessed with the modified Rankin scale score at discharge.

RESULTS

NAFLD was found in 42.5% of the study population. The prevalence of diabetes was significantly higher among patients with NAFLD than those without NAFLD (P = .001). Waist circumference was significantly higher among patients with NAFLD than those without NAFLD (P < .05). Patients with NAFLD had significantly higher glucose, Triglycerides, Low density lipoprotein, serum alanine aminotransferase and aspartate aminotransferase than those without NAFLD (P < .05 for each comparison). National Institutes of Health Stroke Scale score at admission and modified Rankin scale score at discharge were significantly higher in patients with NAFLD than those without NAFLD (P < .05 for each comparison).

CONCLUSION

NAFLD was found in 42.5% of acute ischemic stroke patients. NAFLD might be associated with more severe stroke and worse outcome.

Evaluation of oxidative stress markers in the heart and liver of rainbow trout (Oncorhynchus mykiss walbaum) exposed to the formalin

The aim of this study was to examine change in lipid and protein oxidation biomarkers, transamination enzymes and lactate dehydrogenase activities, lactate and pyruvate levels in liver and heart tissue of rainbow trout (Oncorhynchus mykiss Walbaum) that was exposed to formalin baths. Increase of 2-thiobarbituric acid reactive substances and carbonyl derivatives of protein oxidative destruction was noticed only in cardiac tissue of formalin-exposed fish. Activity of lactate dehydrogenase and lactate level in the cardiac tissue were elevated, indicating active glycolysis. Effects of formalin disinfection were different in both tissues. Aldehydic and ketonic derivatives of oxidatively modified proteins in liver were consistently reduced upon exposure to the formalin. In support of this, decrease in alanine and aspartate aminotransferases was noticed. Formalin disinfection of rainbow trout results in metabolic plasticity, predominantly in liver with decreased levels of oxidative stress biomarkers and aminotransferases activity. Formalin-induced oxidative stress in the cardiac tissue was more considerable.

ATP-consuming processes in hepatocytes of river lamprey Lampetra fluviatilis on the course of prespawning starvation

The work was performed to establish which of the major ATP-consuming processes is the most important for surviving of hepatocytes of female lampreys on the course of prespawning starvation. The requirements of protein synthesis and Na(+)-K(+)-ATPase for ATP in the cells were monitored by the changes in mitochondrial membrane potential (MMP) in the presence of corresponding inhibitors from the peak of metabolic depression (January-February) to the time of recovery from it (March-April) and spawning (May). Integrity of lamprey liver cells was estimated by catalytic activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in blood plasma. In January-February, the share of ATP necessary for protein synthesis was 20-22%, whereas before spawning it decreased to 8-11%. Functioning of Na(+)-K(+)-pump required 22% of cellular ATP at the peak of metabolic depression, but 38% and 62% of ATP in March-April and May, respectively. Progression of prespawning period was accompanied by 3.75- and 1.6-fold rise of ALT and AST activities in blood plasma, respectively, whereas de Ritis coefficient decreased from 2.51±0.34 to 0.81±0.08, what indicates severe damage of hepatocyte membranes. Thus, the adaptive strategy of lamprey hepatocytes to develop metabolic depression under conditions of energy limitation is the selective production of proteins necessary for spawning, most probably vitellogenins. As spawning approaches, the maintenance of transmembrane ion gradients, membrane potential and cell volume to prevent premature cell death becomes the priority cell function.

Exposure to different glyphosate formulations on the oxidative and histological status of Rhamdia quelen

Due to the wide use of glyphosate (GLY) in soybean cultivation, their residues in the environment may affect non-target organisms such as fish, developing toxic effects. Despite GLY being widely used in Brazil, there are few studies comparing the effects of commercial formulations in native freshwater fish species. Silver catfish (Rhamdia quelen) were exposed to three different commercial formulations of GLY 48% (Orium(®), Original(®) and Biocarb(®)) at 0.0, 2.5 and 5.0 mg/L for 96 h. The effects in thiobarbituric acid-reactive substances (TBARS), catalase (CAT), superoxide dismutase (SOD), glutathione-S-transferase (GST) and histological alterations were analysed in the liver, whereas alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were studied in the plasma. In the liver, TBARS levels increased and CAT decreased in all treatments and herbicides tested in comparison with the control group. The SOD increased at 2.5 mg/L of Orium(®), Original(®) and 5.0 mg/L Orium(®) and Biocarb(®), whereas GST increased at 2.5 mg/L Orium(®) and decreased at 2.5 mg/L Biocarb(®) when compared to the control group. The main histopathological alterations in hepatic tissue were vacuolisation, leucocyte infiltration, degeneration of cytoplasm and melanomacrophage in all GLY treatments. The ALT decreased after exposure to 2.5 mg/L of Biocarb(®) and AST increased at 2.5 mg/L of Orium(®), Original(®) and 5.0 mg/L of Biocarb(®) in comparison with the control group. In summary, the oxidative damage generated by GLY may have caused the increased formation of free radicals that led to the histological alterations observed in hepatocytes.

Progesterone causes metabolic changes involving aminotransferases and creatine kinase in cryopreserved bovine spermatozoa

Progesterone (P4) is capable of inducing acrosome reaction in many species. The objective of this study was to determine the activity of enzymes involved in metabolism that contribute to the redox state and supply energy for acrosome reaction in cryopreserved bull spermatozoa. To accomplish this aim, acrosome reaction was induced by P4 in capacitated and non-capacitated samples. Alanine and aspartate aminotransferases (ALT, AST) and creatine kinase (CK) activities were measured spectrophotometrically at 340 nm after acrosome reaction with P4. Oxygen consumption was measured polarographically. ALT and AST activities increased by the addition of P4 capacitated and non-capacitated samples. P4 addition provoked an increase in CK activity in non-capacitated spermatozoa compared to heparin capacitated spermatozoa with or without P4 addition. P4 increased oxygen consumption, the percentage of acrosome reacted spermatozoa as well as the absence of acrosome integrity in both capacitated and non-capacitated bovine spermatozoa, but oxygen consumption in P4 samples was significantly lower than in heparin capacitated spermatozoa (P<0.05). Acrosome reaction induction by P4 required different creatine kinase activity with the same oxygen consumption and transaminases level to maintain oxidative metabolism and redox state through reducing equivalents transfer between cytosolic and mitochondrial compartment. In conclusion, P4 induces a lower oxidative metabolism during acrosome reaction in bovine cryopreserved spermatozoa, compared to heparin induced capacitation process.

Liver enzymes, metabolomics and genome-wide association studies: From systems biology to the personalized medicine

For several decades, serum levels of alanine (ALT) and aspartate (AST) aminotransferases have been regarded as markers of liver injury, including a wide range of etiologies from viral hepatitis to fatty liver. The increasing worldwide prevalence of metabolic syndrome and cardiovascular disease revealed that transaminases are strong predictors of type 2 diabetes, coronary heart disease, atherothrombotic risk profile, and overall risk of metabolic disease. Therefore, it is plausible to suggest that aminotransferases are surrogate biomarkers of “liver metabolic functioning” beyond the classical concept of liver cellular damage, as their enzymatic activity might actually reflect key aspects of the physiology and pathophysiology of the liver function. In this study, we summarize the background information and recent findings on the biological role of ALT and AST, and review the knowledge gained from the application of genome-wide approaches and “omics” technologies that uncovered new concepts on the role of aminotransferases in human diseases and systemic regulation of metabolic functions. Prediction of biomolecular interactions between the candidate genes recently discovered to be associated with plasma concentrations of liver enzymes showed interesting interconnectivity nodes, which suggest that regulation of aminotransferase activity is a complex and highly regulated trait. Finally, links between aminotransferase genes and metabolites are explored to understand the genetic contributions to the metabolic diversity.

Phytochemical analysis of Jatropha curcas L. during different seasons and developmental stages and seedling growth of wheat (Triticum aestivum L) as affected by extracts/leachates of Jatropha curcas L

Jatropha curcas shows invasive characters and is a significant source of many phytochemicals with varying biological activities. Different plant parts of Jatropha curcas L exhibited variation in their phytochemical constituents. Leaves and ovary walls were found to contain higher contents of total phenols, tannins and phytic acid whereas free amino acids were greater in leaves. Young leaves of Jatropha show greater contents of all these metabolites. Further, plants exhibit seasonal differences as leaves collected during summer (May-June) have greater accumulation of total phenols, tannins and free amino acids however, phytic acid was more during rainy season. Leachates and extracts in their higher concentrations adversely affected the germination and growth of wheat seedlings however, lower concentrations were more or less stimulatory. These treatments not only decreased the length, fresh and dry weight of seedlings but also affected the chlorophyll contents and activity of enzymes such as nitrate reductase, aminotransferases in wheat seedlings however, the activity of superoxide dismutase and ascorbate peroxidases increased. Experiments indicate harmful allelopathic effects of Jatropha leachates /extracts on wheat seedlings, hence further experimentation and analysis is recommended before continued plantation of Jatropha particularly on fertile soils. However. Growth of Jatropha plants on saline soils and their potential for accumulating sodium, potassium and chloride are the attributes suggesting the possibility of use of Jatropha plants in improving saline soils.

Liver enzymes and risk of cardiovascular disease in the general population: a meta-analysis of prospective cohort studies

BACKGROUND

Gamma glutamyltransferase (GGT), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP), commonly used markers of liver dysfunction, have been implicated with risk of cardiovascular disease (CVD). However, the strength and consistency of their associations in the general population have not been reliably quantified.

METHODS

We synthesized available prospective epidemiological data on the associations of baseline levels of GGT, ALT, AST, and ALP with CVD [composite CVD, coronary heart disease (CHD), or stroke outcomes]. Relevant studies were identified in a literature search of MEDLINE, EMBASE, and Web of Science up to December 2013. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using random effects models.

RESULTS

Twenty-nine unique cohort studies with aggregate data on over 1.23 million participants and 20,406 cardiovascular outcomes were included. The pooled fully adjusted RRs (95% CIs) for CVD were 1.23 (1.16-1.29) and 1.08 (1.03-1.14) per 1-standard deviation change in log baseline levels of GGT and ALP levels respectively. There was no evidence of an association of ALT or AST with CVD, however, ALT was somewhat inversely associated with CHD 0.95 (0.90-1.00) and positively associated with stroke 1.01 (1.00-1.02) in stratified analysis. Tests for nonlinearity were suggestive of linear relationships of GGT and ALP levels with CVD risk.

CONCLUSIONS

Baseline levels of GGT and ALP are each positively associated with CVD risk and in a log-linear fashion. There may be variations in the associations of ALT with cause-specific cardiovascular endpoints, findings which require further investigation.

Evaluation of abnormal liver tests

The routine use of serum biochemical tests allows for the detection of acute and chronic liver injury before the onset of symptoms. These tests consist of markers of hepatocellular injury (aminotransferases and APs); tests of liver metabolism (total bilirubin); and tests of liver synthetic function (serum albumin and PT). Noninvasive tests for assessment of liver fibrosis are promising tools for diagnosis and prognosis of patients with chronic liver disease. A comprehensive history, physical examination, and assessment of pattern of liver injury with additional laboratory and imaging testing establish the cause of hepatobiliary disease in most cases.

Association between nonalcoholic fatty liver disease and acute ischemic stroke severity and outcome

AIM: To evaluate the association of nonalcoholic fatty liver disease (NAFLD) with acute ischemic stroke severity and in-hospital outcome.

METHODS: We prospectively studied all patients who were admitted in our Department with acute ischemic stroke between September 2010 and August 2012 (n = 415; 39.5% males, mean age 78.8 ± 6.6 years). The severity of stroke was assessed with the National Institutes of Health Stroke Scale (NIHSS) score at admission. NALFD was defined as serum alanine aminotransferase and/or aspartate aminotransferase levels above the upper limit of normal in the absence of other causes of elevated aminotransferases levels [chronic hepatitis B or C, drug toxicity, increased alcohol consumption (> 21 and > 14 drinks per week in men and women, respectively), cholestatic diseases or rhabdomyolysis]. The outcome was assessed with the modified Rankin scale (mRS) score at discharge and in-hospital mortality. Adverse outcome was defined as mRS score at discharge ≥ 2. Dependency at discharge was defined as mRS score between 2 to 5.

RESULTS: NAFLD was present in 7.7% of the study population. Patients with NAFLD had lower serum high-density lipoprotein cholesterol and higher triglyceride levels than patients without NAFLD (P < 0.05 for both comparisons). Demographic data, the prevalence of other cardiovascular risk factors and the prevalence of established CVD did not differ between the two groups. At admission, the NIHSS score did not differ between patients with and without NAFLD (6.3 ± 6.4 and 8.8 ± 9.6, respectively; P = NS). At discharge, the mRS score did not differ between the two groups (1.9 ± 2.2 and 2.6 ± 2.2 in patients with and without NAFLD, respectively; P = NS). Rates of dependency at discharge were also similar in patients with and without NAFLD (36.8% and 55.0%, respectively; P = NS) as were the rates of adverse outcome (42.9% and 58.6%, respectively; P = NS). In-hospital mortality rates also did not differ between the 2 groups (8.0% and 7.0% in patients with and without NAFLD, respectively; P = NS).

CONCLUSION: The presence of NAFLD in patients admitted for acute ischemic stroke does not appear to be associated with more severe stroke or with worse in-hospital outcome.

Prevalence and causes of abnormal liver function in patients with coeliac disease

BACKGROUND & AIMS

Coeliac disease patients frequently display mild elevation of liver enzymes and this abnormality usually normalizes after gluten-free diet. To investigate the cause and prevalence of altered liver function tests in coeliac patients, basally and after 1 year of gluten-free diet.

PATIENTS AND METHODS

Data from 245 untreated CD patients (196 women and 49 men, age range 15-80 years) were retrospectively analysed and the liver function tests before and after diet, as well as associated liver pathologies, were assessed.

RESULTS

Overall, 43/245 (17.5%) patients had elevated values of one or both aminotransferases; the elevation was mild (<5 times the upper reference limit) in 41 (95%) and marked (>10 times the upper reference limit) in the remaining 2 (5%) patients. After 1 year of gluten-free diet, aminotransferase levels normalized in all but four patients with HCV infection or primary biliary cirrhosis.

CONCLUSIONS

In coeliac patients, hypertransaminaseaemia at diagnosis and the lack of normalization of liver enzymes after 12 months of diet suggest coexisting liver disease. In such instance, further evaluation is recommended to exclude the liver disease. Early recognition and treatment of coeliac disease in patients affected by liver disease are important to improve the liver function and prevent complications.

Cholestasis of Pregnancy : A Prospective Study

BACKGROUND

Intrahepatic cholestasis of pregnancy (ICP) typically occurs during the last trimester of gestation. The most accurate marker for diagnosis and follow-up of ICP is increased total bile acid levels (above 11.0 micro mol/L) [1]. ICP is a benign disease with no consequences to the mother but it is associated with an increased rate of fetal morbidity and mortality.

METHOD

A prospective study was carried out in 1500 deliveries which included 27 cases of ICP. The mode of delivery, complications and fetal outcome of intrahepatic cholestasis group were compared with rest of the deliveries. Cases having pruritic lesions of skin, viral hepatitis, gall stones, autoimmune liver diseases were excluded. Random selection of 300 pregnancies in the control group was done and their liver function tests were carried out for comparison. All the patients with cholestasis of pregnancy were treated with ursodeoxycholic acid.

RESULT

The levels of the aminotransferases and alkaline phosphatase levels rose significantly (p < 0.05) in the study group. Cholestatic group did not have any significant difference in mode of delivery or fetal outcome from the control group. The patients in the study group were treated with ursodeoxycholic acid with significant relief in symptoms (p < 0.01), while improvement in serum bilirubin levels, alkaline phosphatase levels and aminotransferases levels were not statistically significant.

CONCLUSION

In absence of serum bile acids levels, alkaline phosphatase and aminotransferases levels may help in diagnosis and management of cholestasis of pregnancy. Ursodeoxycholic acid treatment is effective in reducing the pruritus.

In vivo studies on artificial induction of thermotolerance to detached panicles of wheat (Triticum aestivum L) cultivars under heat stress

The mechanism imparting thermotolerance by gibberellic acid (GA3) and abscisic acid (ABA) is still unresolved using either spraying technique or in vitro conditions. Alternative way of studying these effects under near in vivo conditions is through the use of liquid culturing technique. Effects of GA3 and ABA (100 μM) on sucrose metabolism (invertase and sucrose synthase) and aminotransferases (GOT and GPT) in relation to starch and protein accumulation were studied in detached panicles of three wheat (Triticum aestivum L.) cultivars PBW 343, C 306 (heat tolerant) and WH 542 (heat susceptible) cultured in a liquid medium. Ears were subjected to heat shock treatment (45 °C for 2 h) and then maintained at 25 °C for 5 days. Heat shock treatment resulted in a significant decline in starch content but caused a marked build -up of total free sugars and protein content in grains of all cultivars. However, activities of acid and neutral invertases increased only in tolerant cultivars but reduced in susceptible cultivar. Following treatment with GA3 contents of starch and free sugars increased in grains maintained at 25 °C but free sugar content decreased in stressed grains compared to control. ABA application showed inhibitory effect on starch accumulation under normal temperature but was promotory under stress conditions. Concomitantly, soluble protein content also increased in conjunction with an increase in the activities of glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT). Apparently, the wheat grain responds to heat shock mediated disruption of carbon metabolism by a compensatory effect on nitrogen metabolism. GA3 stimulated grain sink activity both under stress and non stress condition while ABA was promotory only under stress condition.

Phlebotomy improves histology in chronic hepatitis C males with mild iron overload

AIM: To investigate the usefulness of mild iron depletion and the factors predictive for histological improvement following phlebotomy in Caucasians with chronic hepatitis C (CHC).

METHODS: We investigated 28 CHC Caucasians with persistently elevated serum aminotransferase levels and non responders to, or unsuitable for, antiviral therapy who underwent mild iron depletion (ferritin ≤ 70 ng/mL) by long-term phlebotomy. Histological improvement, as defined by at least one point reduction in the staging score or, in case of unchanged stage, as at least two points reduction in the grading score (Knodell), was evaluated in two subsequent liver biopsies (before and at the end of phlebotomy, 48 ± 16 mo apart).

RESULTS: Phlebotomy showed an excellent safety profile. Histological improvement occurred in 12/28 phlebotomized patients. Only males responded to phlebotomy. At univariate logistic analysis alcohol intake (P = 0.034), high histological grading (P = 0.01) and high hepatic iron concentration (HIC) (P = 0.04) before treatment were associated with histological improvement. Multivariate logistic analysis showed that in males high HIC was the only predictor of histological improvement following phlebotomy (OR = 1.41, 95% CI: 1.03-1.94, P = 0.031). Accordingly, 12 out of 17 (70%) patients with HIC ≥ 20 μmol/g showed histological improvements at the second biopsy.

CONCLUSION: Male CHC Caucasian non-responders to antiviral therapy with low-grade iron overload can benefit from mild iron depletion by long-term phlebotomy.

Effect of Aqueous Extract of Psidium Guajava Leaves on Liver Enzymes, Histological Integrity and Hematological Indices in Rats

BACKGROUND

Serum alanine aminotransferase (ALT), aspartate aminotransferase(AST), alkaline phosphatase (ALP), albumin and total protein levels, as well as the tissue histological assay are known to be useful in assessing the functional integrity of the liver. Also, assessment of red and white blood cells count, hematocrit and hemoglobin concentrations is useful in determining the effect of some chemical substances on hemotopoietic system. In recent times, reports from medicinal plants research indicate that extracts from some plants are both hepatotoxic and hematotoxic, while others on the other hand are reported to be hepatoprotective and hematopoietic in action. This study considers the effects of aqueous extract of Psidium guajava (P. guajava) leaves on the histology and biochemical indices of liver function as well as hematological indices in rats.

METHODS

In this study, phytochemical screening of the aqueous extract of P. guajava leaves was carried out. Also, male and female rats were administered with 200 mg/kg body weight oral daily doses of aqueous extract of P. guajava leaves for a period of 30 days. At the end of the administration period, the rats were anaesthesized with chloroform vapors and dissected for the collection of blood and liver tissues which were used for the hematopoietic and liver functions investigations.

RESULTS

Preliminary phytochemical analysis of the plant leaves showed the presence of alkaloids, flavonoids, glycosides, polyphenols, reducing compounds, saponins and tannins. Liver function tests revealed that the serum ALT, AST and ALP, as well as the concentrations of total protein and albumin in male and female rats were not significantly (P > 0.05) affected by the oral administration of the extract. Histopathological study also did not show any adverse alteration in the morphological architecture of the liver tissues in both sexes of the animal model. However, red blood cell counts, hemotocrit and hemoglobin concentrations increased significantly (P < 0.05) on administration of the extract in both male and female rats. It was therefore observed that the effect of the extract on male rats was not significantly different (P > 0.05) from that obtained for the female rats.

CONCLUSIONS

The results of this present study suggested that aqueous extract of Psidium guajava leaves may be hepatoprotective, and not hepatotoxic, with hematopoietic potentials in both male and female rats. These findings are therefore of clinical importance given the various reported medicinal potentials of the plant.

Comparative Hepatoprotective Effect of Vitamins A and E Against Gasoline Vapor Toxicity in Male and Female Rats

Background

Plasma alanine transferase(ALT), aspartate transferase(AST), α-glutamyl transferase(GGT), and alkaline phosphatase(ALP) activities are known biomarkers in assessing hepatic functional integrity. A remarkable rise in the activities of these enzymes normally signifies hepatotoxicity of chemical agent(s) in the biological system. Exposure to 17.8 cm³h^-1m^-3 of PMS blend unleaded gasoline vapors (UGV) for 6 hr/day, 5 days/week for 20 weeks have been reported to cause hepatotoxicity in rats.

Methods

In this study, the comparative hepatoprotective effect of vitamins A (retinol) and E (α-tocopherol) against UGV-induced toxicity was assessed in male and female rats. Retinol and α-tocopherol at prophylactic dosage (400 and 200 IU/kg/day, respectively) were separately administered orally to the test rats concomitant with exposure to UGV in the last two weeks of the experiment.

Results

The results of this study indicated that exposure to UGV caused significant increase (P < 0.05) in the activities of serum ALT, AST, ALP, GGT and bilirubin in male and female rats. Oral administration of prophylactic doses of retinol and α-tocopherol produced a significant decrease (P < 0.05) in the activities of these parameters in male and female test rats, compared with the non-treated test rats; but insignificant increase(P ≥ 0.05), compared with the control. However, the hepatoprotective effect of α-tocopherol was observed to be more potent than that of retinol.

Conclusions

The result of this study demonstrated that the hepatoprotective potency of α-tocopherol against gasoline vapors toxicity was higher than that of retinol in male and female rats, although the female gender of the animal model responded to treatment with both vitamins better than the males. Hence, the work suggested the beneficial effects of both vitamins against hepatotoxicity in individuals frequently exposed to gasoline vapors.

The Hepatoprotective Effect of Vitamin A against Gasoline Vapor Toxicity in Rats

Background

Changes in the activities of plasma alanine amino transferase (ALT), aspartate amino transferase (AST), gamma glutamyl transferase (GGT), and alkaline phosphatase (ALP) are used to assess the functional state of the liver. Significant increase in the activities of these enzymes commonly indicates the hepatotoxicity of chemical agent(s) in the body. Exposure of male and female rats to 17.8 cm³h^-1m^-3 of Premium Motor Spirit (PMS) blend unleaded gasoline (UG) vapors for 6 hr/day, 5 days/week for 20 weeks have been observed to cause hepatotoxicity. In this study, the potential hepatoprotective effect of vitamin A (retinol) against gasoline vapours-induced toxicity was investigated in male and female rats.

Methods

Retinol (400 IU/kg/day) was orally administered to the test rats concomitant with the gasoline vapor exposure in the last two weeks of the experiment.

Results

The results obtained from this study showed that exposure to gasoline vapors caused significant increase (P < 0.05) in the activities of serum ALT, AST, ALP, GGT and bilirubin in both male and female rats. The treatment of the male and female test rats with vitamin A produced a significant decrease (P < 0.05) in the activities of these parameters, compared with the test rats without treatment; but insignificant increase(P ≥ 0.05), compared with the control.

Conclusions

The result of this study demonstrates the beneficial effects of retinol, at prophylactic dosage, against gasoline vapours hepatotoxicity in male and female rats, thereby suggesting that retinol may be used to prevent hepatotoxicity in individuals frequently exposed to gasoline vapours.