Liver Aspartate Aminotransferase Activity Research Articles

Biochemical and Toxicological Evaluations of Aqueous Extract of Parquetina nigrescens (Afzel.) leaves on Mifepristone-induced Polycystic Ovarian Syndrome in Rats

The biochemical and toxicological effects of aqueous extract of Parquetina nigrescens leaves (AEPNL) at the doses of 50, 100, and 200 mg/kg body weight on mifepristone-induced in Polycystic Ovarian Syndrome (PCOS) was investigated in female Wistar rats. Sixty female Wistar rats (190.00 ± 13.00 g) were assigned into 6 groups (A - F) of ten each: animals in group A received 0.5 ml of distilled water orally on daily basis for 30 days while the mifepristonized rats in groups B, C, D and E also received orally 0.5 ml of distilled water, 7.14mg/kg of metformin (reference drug) and same volume of the extract corresponding to 50, 100, and 200 mg/kg body weight of AEPNL respectively after which levels of some biochemical and toxicological indices were determined. AEPNL aggravated mifepristone-treatment related increases in albumin, total protein and liver aspartate aminotransferase activity and mitigated the increases in globulin, total bilirubin, urea, creatinine, liver and serum alkaline phosphatase and alanine aminotransferase activities, and no treatment-related histoarchitectural changes occurred in the liver, kidney and uterus of the female rats. Therefore, the aqueous extract of Parquetina nigrescens leaves attenuated and also aggravated some biochemical parameters in the serum, liver and kidney but with no histological changes in the liver, kidney and uterus of the mifepristonized female Wistar rats.
 Keywords: Mifepristone, toxicology, Parquetina nigrescens, Polycystic Ovarian Syndrome, histology

Biochemical and Toxicological Evaluations of Aqueous Extract of Parquetina nigrescens (Afzel.) leaves on Mifepristone‐induced Polycystic Ovarian Syndrome in Rats

The biochemical and toxicological effects of aqueous extract of Parquetina nigrescens leaves (AEPNL) at the doses of 50, 100, and 200 mg/kg body weight on mifepristone‐induced in Polycystic Ovarian Syndrome (PCOS) was investigated in female Wistar rats. Fifty female Wistar rats (190.00 ± 13.00 g) were assigned into 5 groups (A – E) of ten each: animals in group A received 0.5 ml of distilled water orally on daily basis for 30 days while the mifepristonized rats in groups B, C, D and E also received orally 0.5 ml of distilled water and same volume of the extract corresponding to 50, 100, and 200 mg/kg body weight of AEPNL respectively after which levels of some biochemical and toxicological indices were determined. AEPNL aggravated mifepristone‐treatment related increases in albumin, total protein and liver aspartate aminotransferase activity and mitigated the increases in globulin, total bilirubin, urea, creatinine, liver and serum alkaline phosphatase and alanine aminotransferase activities, and no treatment‐related histoarchitectural changes occurred in the liver, kidney and uterus of the female rats. Therefore, the aqueous extract of Parquetina nigrescens leaves attenuated and also aggravated some biochemical parameters in the serum, liver and kidney but with no histological changes in the liver, kidney and uterus of the mifepristonized female Wistar rats.

Mortality, Oxidative Stress and Hepatotoxicity in Juvenile African Catfish, Clarias gariepinus Burchell, Exposed to Lead and Cypermethrin

In this study, juvenile catfish (Clarias gariepinus) were exposed to 2 mg/L Pb, 0.5 μg/L cypermethrin, or both for 96 h. Survival ranged from 100% in both treatments without cypermethrin, to 50% in fish exposed to cypermethrin only or the mixture. There were significant decreases in liver lysozyme, γ-glutamyl transpeptidase, and alanine aminotransferase activities in fish exposed to cypermethrin or the mixture. Liver aspartate aminotransferase activity (AST) showed a significant reduction after exposure to Pb or cypermethrin alone, and the effect of the mixture on AST was additive or potentially synergistic. Liver lipid peroxidation (LPO) was increased in fish exposed to the mixture compared to those exposed to cypermethrin only, indicating that Pb presence enhanced LPO caused by cypermethrin. Our study demonstrates the potential for toxic interaction between Pb and cypermethrin in fish and suggests that due to the varying responses to contaminant mixtures in our study, researchers should consider using a variety of biomarkers.

Modulation of key enzymes of glycolysis, gluconeogenesis, amino acid catabolism, and TCA cycle of the tropical freshwater fish Labeo rohita fed gelatinized and non-gelatinized starch diet

A 60-day experiment was conducted to study the effect of dietary gelatinized (G) and non-gelatinized (NG) starch on the key metabolic enzymes of glycolysis (hexokinase, glucokinase, pyruvate kinase, and lactate dehydrogenase), gluconeogenesis (glucose-6 phosphatase and fructose-1,6 bisphosphatase), protein metabolism (aspartate amino transferase and alanine amino transferase), and TCA cycle (malate dehydrogenase) in Labeo rohita juveniles. In the analysis, 234 juveniles (2.53 +/- 0.04 g) were randomly distributed into six treatment groups each with three replicates. Six semi-purified diets containing NG and G cornstarch, each at six levels of inclusion (0, 20, 40, 60, 80, and 100) were prepared viz., T1 (100% NG, 0% G starch), T2 (80% NG, 20% G starch), T3 (60% NG, 40% G starch), T4 (40% NG, 60% G starch), T5 (20% NG, 80% G starch), and T6 (0% NG, 100% G starch). Dietary G:NG starch ratio had a significant (P < 0.05) effect on the glycolytic enzymes, the highest activities were observed in the T6 group and lowest in the T1 group. On the contrary, the gluconeogenic enzymes, the glucose-6-phosphatase and fructose-1,6 bisphosphatase activities in the organs, liver and kidney were recorded highest in the T1 group and lowest in the T6 group. The liver aspartate amino transferase activity showed an increasing trend with the decrease in the dietary G level. However, the muscle aspartate amino transferase activity was not significantly (P > 0.05) influenced by the type of dietary starch. The alanine amino transferase activity in both liver and muscle showed an increasing trend with the decrease in the dietary G level. The liver and muscle malate dehydrogenase activities were lowest in the T6 group and highest in the T1 group. Results suggest that NG (100%) starch diet significantly induced more the enzyme activities of amino acid metabolism, gluconeogenesis, and TCA cycle, whereas partial or total replacement of raw starch by gelatinized starch increased the glycolytic enzyme activity.

Toxicity of &lt;i&gt;Erythrophleum guineense&lt;/i&gt; stem-bark: role of alkaloidal fraction

The effect of the in vivo administration of the total alkaloidal fractions of the stem-bark of the Erythropleum guineense on certain biological parameters of Sprague-Dawley rats was investigated. The results revealed that plasma alanine aminotransferase activity, liver aspartate aminotransferase activity, liver glycogen, liver protein, creatinine and haemoglobin concentrations were reduced while plasma aspartate aminotransferase activity, liver alanine aminotransferase activity, plasma urea concentration, bilirubin concentration and alkaline phosphatase activity were elevated in Sprague -Dawley rats treated with total alkaloidal fractions of E. guineense stem-bark. The phytochemical assays revealed that the chemical composition of E. guineense include alkaloids, saponins, cardiac glycosides and tannins. The toxicity of the stem-bark of E. guineense could be attributed to the combined toxicity of other constituents such as tannins, saponins and glycosides with the alkaloids as earlier speculated. Key Words: Toxicity, hepatic, Erythrophelum guineese, alkaloidal fraction, aminotransferases, alkaline phosphatase. Afr. J. Trad. CAM (2004) 1: 45-54

Optimal conditions for determination of aspartate aminotransferase activity in rainbow trout and whitefish

Aspartate aminotransferase (AspAT) activity is frequently used as a biochemical indicator offish physiological status, the clinical indicator of pathologies related to diseases and/or toxicity stress. However, there has been a lack of consensus on the optimal conditions for measuring AspAT activity in fish tissues and body fluids. In this study we used the spectrophotometric method recommended by the International Federation of Clinical Chemistry (IFCC) which was based on absorbance changes at 339 nm due to NADH oxidation, to test effects of L-aspar-tate, pH and presence of pyridoxal 5'-phosphate on AspAT activity in rainbow trout (Oncorhynchus mykiss) and whitefish (Coregonus clupeaformis) blood plasma and liver extracts. We also tested the effect of temperature at range 10–40°C on the liver AspAT activity and calculated the relationships of AspAT activities at various temperatures at range 10–30°C. Blood and liver AspAT activities were highest at pH 7.8. Liver activity was highest at 60 mM L-aspartate concentration. Pyridoxal 5'-phosphate stimulated activities in both tissues by 10–20 %. The IFCC method with few modifications is recommended for AspAT assay in fish and offers a replacement for the numerous AspAT assays currently in use.

Liver aspartate aminotransferase activity as a power function of body weight

Total liver enzyme activity ( E) for aspartate aminotransferase (ASAT; EC 2.6.1.1) per gram body weight ( W) decreases in six species as body weight increases from mice to cattle according to the equation E W 0.85 = c , where c is a constant. The 0.85 power of body weight thereby provides a reference standard for the direct arithmetic comparison of liver ASAT activities in six species with different body weights. The use of W 0.85 should provide a tool in clinical studies in which data from experimental animals must be related to humans, e.g., in establishing the relationship between drug dosage (or toxicity) and body weight.

Determination of Vitamin B6 Deficiency in Rainbow Trout (Salmo gairdneri) by Liver Enzyme Assay and HPLC Analysis

Rainbow trout (Salmo gairdneri), initially averaging 125 g, were fed a complete or a pyridoxine-deficient diet for 14 wk. Vitamin B6 status was evaluated biweekly by direct measurement of liver pyridoxine and pyridoxal levels by HPLC and by determining pyridoxal-5′-phosphate-enhanced liver aspartate aminotransferase (ASAT) activity. By 14 wk, mortality had severely reduced the number of fish remaining in the pyridoxine-deficient group. At 14 wk, no significant differences in liver pyridoxine and pyridoxal levels were detected between the trout fed the complete or pyridoxine-deficient diet. Significant differences between dietary groups are found in ASAT activity in liver and percent stimulation of liver ASAT by the addition of pyridoxal-5′-phosphate after 8 wk. Clinical signs of vitamin B6 deficiency including anorexia, listlessness, frantic and erratic swimming, and ataxia were observed after 11 wk of feeding a pyridoxine-deficient diet. This study shows that vitamin B6 deficiency in rainbow trout can be readily determined weeks before signs of clinical deficiency are apparent by measuring pyridoxine-enhanced liver ASAT activity. However, liver levels of pyridoxine and pyridoxal are not sensitive indicators of vitamin B6 status.

Effects of temperature, salinity, and feeding on aminotransferase activity in the liver and white muscle of rainbow trout ( Salmo gairdneri Richardson)

1. 1. The liver-somatic index of rainbow trout is governed by temperature and salinity, and by the interaction of these two factors. 2. 2. The overall liver-alanine aminotransferase activity (in units/100 g body weight) increases slightly with increasing salinity of the surroundings in the case of rainbow trout. 3. 3. The overall liver-aspartate aminotransferase activity (in units/100 g body weight) in rainbow trout depends on their food and the temperature at which they are kept. 4. 4. Salinity adaptation leads to reductions in the specific alanine and aspartate aminotransferase activity in the liver of rainbow trout. 5. 5. The specific alanine aminotransferase activity in the muscle of starving rainbow trout kept in diluted seawater (580 mOsm/1, 18°C) is clearly higher than in control animals kept in tapwater.