Aspartate Aminotransferase

Determining and understanding the enzyme activity in different types of Oncorhynchus mykiss muscle (heart, white and red) by comparing rate of reaction (V) of the succinate to the substrate concentration [S]

The conditions that lead to chronic liver disease are vast but they fall into five groups (Chronic liver, 2011). The first group is the viral group classification which includes conditions such as hepatitis B and C (Chronic liver, 2011). The second group is the metabolic group which includes diseases such as Wilson’s disease (Chronic liver, 2011). The third group is the autoimmune response group which includes primary biliary cirrhosis sufferers (Chronic liver, 2011). The fourth group is the toxin-related group which includes alcoholism and the last is the miscellaneous group with ailments such as right heart failure (Chronic liver, 2011). Within these groups there is a silent killer though which raises the risk for that group. That is the toxin-related group because alcoholism leads to cirrhosis and then to hepatitis (Chronic liver, 2011). That group alone takes a person through three groups in one shot.

Cirrhosis is the eighth leading cause of death in the United States and the thirteenth leading cause of death worldwide.1 Cirrhosis is the irreversible fibrosis of the liver characterized by hepatic architectural distortion secondary to fibrous tissue and the formation of regenerative nodules.2 These anatomical changes cause hepatic vascular resistance and an increase in blood flow leading to portal hypertension. Porto-systemic collaterals develop in order to overcome the increased portal pressure gradient.3 Nitric oxide, an endogenous vasodilator is also released in effort to overcome portal pressure with the expense of causing systemic vasodilation and a decrease in blood pressure. As a result, a marked activation of neurohumoral vasoactive factors occurs in an effort to maintain an effective arterial blood pressure. Hypervolemia, increased cardiac index, decreased systemic vascular resistance, and systemic hypotension are manifestations of portal hypertension.3 Chronic hepatitis B virus (HBV), hepatitis C virus (HCV), alcoholism, nonalcoholic steatohepatitis (NASH), and non-alcoholic fatty liver disease (NAFLD) are all major causes of cirrhosis.

It was found that BChE showed broader substrate specificity when compared to AChE, hydrolysing all substrates (at least to some extent), excluding Carbachol. AChE failed to hydrolyse suxamethonium or carbachol to any extent. It was also found that Atropine and Malathion failed to significantly inhibit either cholinesterase, whereas Edrophonium displayed short-acting inhibition. Physostigmine, Nestogmine and Carbachol displayed greater inhibition.

a. -in both hepatic functions are not functioning well hence requires calculation adjustments of drugs to suit the patient needs

In this experiment we tested the effects that enzymes and substrate have on chemical reaction rates, which is the rate at which chemical reactions occur.. This experiment tested how different concentrations of enzyme and substrate affected the light absorption measurements on a spectrophotometer. The experiment also tested how temperature affected the light absorption, and in a separate test, the effect of the enzyme inhibitor hydroxylamine was also tested. In the first test conducted, 3 different concentrations of enzyme, and three different concentrations of substrate were measured in a spectrophotometer. For the enzyme and the substrate, the measurements got higher as the concentrations were higher, but the over measurements of the substrate were smaller than those of the enzyme. In the second test conducted, the medium concentration enzyme was tested under the temperatures; 4°C, 23°C, 37°C, and 60°C. The measurements in this test got higher as the temperature got higher, but did the measurements under 4°C were overall significantly higher than the other temperature measurements. Lastly, the last test conducted showed that the measurements of the substance with 0 and 1 drop of hydroxylamine inhibitor went up, but the measurements of the enzyme with 5 drops of hydroxylamine inhibitor stayed rather low and did not change much. In conclusion, these experiments showed that chemical reaction rates are sped up with higher concentrations of enzyme, substrate,

The normalized SDH activity of two homogenates can be compared by looking at the class statistics for the Liver and Kidney homogenate samples in the data sheet attached. The kidney exhibited higher enzyme SDH activity than the liver. This was in agreement with the proposed hypothesis. Comparing the same two homogenates in which malonate was present, it can be seen that the kidney exhibited higher SDH activity than the liver. Thus, both homogenates did in fact have a decrease in enzyme activity, as malonate inhibits the activity of SDH. In successive experiments more malonate was used, and class statistics, not the activity itself, showed lower amounts of enzyme activity/mg protein as reaction number increased and a greater significance. Thus, malonate’s effect did increase proportionally to its concentration. There was a significant difference in SDH activity between the liver and kidney homogenates (p=0.0001)0.05). (Figure 1)

The Enzyme Properties Lab was performed to analyze the effects of pH, enzyme concentration, and temperature on the catalytic rate of enzymes. Many functions within the human body require/involve enzymes. It was found that enzymes have an optimal pH level, catalytic rate increases as the concentration of the enzyme increases, and an optimal temperature. The enzyme that was used throughout the experiment was ALP (alkaline phosphatase enzyme). ALP functions best at a neutral pH level, as it had the largest calculated enzyme activity of 2.05E-03. When pH went above or below the neutral value the enzyme activity tended to fall. ALP’s calculated enzyme activity tended to increase with an increase in enzyme concentration, as the calculated enzyme activity of the high enzyme concentration environment was 0.004607, which was larger than the other conditions. The last part of the experiment involved temperature and it was found that the optimal temperature for the enzyme was 32°C with a calculated enzyme activity of 0.000353. When temperature was below or above the optimal temperature the calculated enzyme activity dropped. Enzymes can begin to change shape and lose function when conditions are not appropriate, which was seen in the enzyme activity of ALP in varying environments. It can be concluded that enzymes play a major role in many reactions, but if conditions (pH, enzyme concentration, and temperature) are not appropriate enzyme activity tends to drop. The results supported the

Sarpogrelate lacked prominent 5-HT1-like, 5-HT3, beta, H1, H2 and M3 antagonist activity and weakly blocked alpha 1-adrenoceptors (pKB = 6.30). (S)-M-1 showed weak affinity for 5-HT1-like receptors (pKB = 6.30), alpha 1-(pKB = 6.80) and beta- (pKB = 6.54) adrenoceptors, while (R)-M-1 was a weak antagonist at histamine H1 receptors (pKB = 6.49) [2].

Giving the fact that NAFLD is usually an asymptomatic disorder, it is often unrecognized in everyday clinical practice. Namely, most patients with NAFLD have no symptoms, and aminotransferase levels which are used as a marker of liver damage, are within normal values in almost half of all patients. NAFLD is strongly associated with type 2 diabetes mellitus (T2DM) and has been linked to increased cardiovascular disease (CVD) risk. It is characterized by insulin resistance and mitochondrial dysfunction6. Indeed, there is a gradual increase in the severity of insulin resistance in the range of NAFLD which may contribute to the evolution of liver damage. Also, it is associated with an increased risk of kidney disease in subjects with multiple CVD

● Less specific activity occurred in the reactions containing the reagent because the presence of the reagent inhibits the activity therefore leading to a smaller number outcome. ● The differences in the crude and mitochondrial fractions support the hypothesis because the protein concentration of the crude extract values shows that the Malone reagent inhibits SDH activity. ● The reactions without the reagent occurred rapidly and the number decreased markedly over 21 minutes. ● The reaction with the reagent occurred much slower and the number decreased just as slow over the 21 minutes. ● The slower reaction supports the hypothesis in that the reagent, Malonate interferred with the binding of succinate to the active site causing an overall slow reaction as the succinate worked to replace the Malonate.

The enzyme lab was used to determine the different factors that could affect the productivity of an enzyme. In the lab, the reaction between the hydrogen peroxide and the liver was an exothermic reaction because the temperature of the test tube rose when the hydrogen peroxide was placed into the liver. Heat is a form of energy and the temperature rose as the reaction progressed. In the test tube B, the temperature rose from room temperature to around r30ºC showing that it was an exothermic reaction. I think that the heat from the reactions of the enzymes inside my body keep my body warm and prevent the environment of these enzymes from becoming too cold and the basic functions of the body could not be carried out.

OAT activity was measured in whole kidneys using the Herzfeld and Knox method. Principle of this assay is that the enzyme will catalyze the conversion of delta amino group of L-ornithine to α-ketoglutarate forming both L-glutamate and L-glutamate semialdehyde ending up with pyrroline-5-carboxylate. Then the amount of dihydeoquinazolium is measured, which results from pyrroline-5-carboxylate interaction with o-aminobenzaldehyde. The end product has a yellow color which can be detected at 440 nm (Heinanen et al. 1998).

Vitamin E (300 mg/day) and vitamin C (300 mg/day) were given to each patient orally for 12 months. Half of the patients had a liver biopsy done on them before and after the trial treatment. The findings of this trial concluded that using both vitamin E and vitamin C combined can help patients with NASH by minimizing the damage from oxidative stress, significantly improving fibrosis, and actually slowing down the process that eventually leads to cirrhosis. When vitamin E is administered along with vitamin C, the combination of both can actively fight against the oxidative stress in the liver. In this study, serum alanine aminotransferase levels improved, along with a decrease in serum thioredoxin, high-sensitivity C-reactive protein, and 8-hydroxydeoxyguanosine levels. This trial suggests that the combination of vitamin C and E should be investigated further to be able to take advantage of the full benefits of vitamin E against nonalcoholic steatohepatitis (11).

HRS is considered one of the most threatening complications of cirrhosis. Prognosis is invariably poor ranging from months in type 2 HRS to weeks to months in type 1 HRS (Alessandria et al., 2005). Multiple studies have been performed to detect the factors that affect prognosis of HRS. Those studies revealed that MELD score (Alessandria et al., 2005), the etiology of the liver disease, the serum creatinine at the time of initiation of treatment, and the urinary sodium (Martinez et al., 2012) were useful prognostic factors.