Comparison of the Hypertransferasemic Effects of Erythropoietin and U-74389G on Aspartate Aminotransferase Levels
Constantinos Tsompos1, Constantinos Panoulis2, Konstantinos Toutouzas3, Aggeliki Triantafyllou4, George C. Zografos5, Kalliopi Tsarea6, Maria Karamperi6, Apostolos Papalois6
1.Department of Gynecology, General Hospital of Thessaloniki "St. Dimitrios", Thessaloniki, Hellas,
2.Department of Obstetrics and Gynecology, Aretaieion Hospital, Athens University, Athens, Attiki, Hellas,
3.Department of Surgery, Ippokrateion General Hospital, Athens University, Athens, Attiki, Hellas,
4.Department of Biologic Chemistry, Athens University, Athens, Attiki, Hellas,
5.Department of Surgery, Ippokrateion General Hospital, Athens University, Athens, Attiki, Hellas,
6.Experimental Research Centre ELPEN Pharmaceuticals, S.A. Inc., Co., Pikermi, Attiki, Hellas.
Citation : Tsompos C, Panoulis C, Toutouzas K, Triantafyllou A, Zografos GC, Tsarea K, Karamperi M, Papalois A. Comparison of the Hypertransferasemic Effects of Erythropoietin and U-74389G on Aspartate Aminotransferase Levels. Clin Res Hematol 2018;1(2):1-7.
Aim: This study calculated the effects on aspartate aminotransferase (AST) levels, after treatment with either of two drugs: The erythropoietin (Epo) and the antioxidant lazaroid (L) drug U-74389G. The calculation was based on the results of two preliminary studies, each one of which estimated the certain influence, after the respective drug usage in an induced ischemia-reperfusion (IR) animal experiment.
Materials and Methods: The two main experimental endpoints at which the serum AST levels were evaluated were the 60th reperfusion min (for the Groups A, C, and E) and the 120th reperfusion min (for the Groups B, D, and F). Especially, Groups A and B were processed without drugs, Groups C and D after Epo administration, whereas Groups E and F after the L administration. Results: The first preliminary study of Epo presented a significant hypertransferasemic effect by 19.73 ± 7.71% (P = 0.0119). The second preliminary study of U-74389G presented a non-significant hypertransferasemic effect by 16.23 ± 8.59% (P = 0.0583). These two studies were coevaluated since they came from the same experimental setting. The outcome of the coevaluation was that L is 0.8224656-fold (0.8211631-0.8237701) less hypertransferasemic than Epo (P = 0.0000).
Conclusions: The antioxidant capacities of U-74389G ascribe 0.8224656-fold less hypertransferasemic effects than Epo (P = 0.0000).
The lazaroid U-74389G (L) may be not famous for its hypertransferasemic capacity (P = 0.0583). U-74389G as a novel antioxidant factor implicates exactly only 260 published studies. The ischemiareperfusion (IR) type of experiments was noted in 18.84% of these studies. A tissue protective feature of U-74389G was obvious in these IR studies. The U-74389G chemically known as 21-[4-(2,6-di-1-pyrrolidinyl-4-pyrimidinyl)-1- piperazinyl]-pregna-1,4,9(11)-triene-3,20-dione maleate salt is an antioxidant complex, which prevents the lipid peroxidation either iron-dependent or arachidonic acidinduced one. Animals' kidney, liver, brain microvascular endothelial cell monolayers, and heart models were protected by U-74389G after IR injury. U-74389G also attenuates the leukocytes, downregulates the pro-inflammatory gene, treats the endotoxin shock, produces cytokine, enhances the mononuclear immunity, protects the endothelium, and presents anti-shock property.
Erythropoietin (Epo) even if is not famous for its hypertransferasemic action (P = 0.4430), it can be used as a reference drug for comparison with U-74389G. Although Epo is met in over 30,606 published biomedical studies, only a 3.57% of them negotiate the known type of IR experiments. Nevertheless, Epo as a cytokine, it is worth of being studied about its effects on aspartate aminotransferase levels (AST) levels too.
This experimental work tried to compare the effects of the above drugs on a rat-induced IR protocol. They were tested by calculating the serum AST level (sASTl) augmentations.
MATERIALS AND METHODS
The Vet licenses under 3693/12-11- 2010 and 14/10-1-2012 numbers, the granting company, and the experiment location are mentioned in preliminary references[1,2]. The human animal care of albino female Wistar rats, 7 days' pre-experimental ad libitum diet, non-stop intraexperimental anesthesiologic techniques, acidometry, electrocardiogram, oxygen supply, and post-experimental euthanasia are also described in preliminary references. Rats were 16-18 weeks old. They were randomly assigned to six (6) groups consisted of n = 10. The stage of 45 min hypoxia was common for all six groups. Afterward, reperfusion of 60 min was followed in Group A; reperfusion of 120 min in Group B; immediate Epo intravenous (IV) administration and reperfusion of 60 min in Group C; immediate Epo IV administration and reperfusion of 120 min in Group D; immediate U-74389G IV administration and reperfusion of 60 min in Group E; and immediate U-74389G IV administration and reperfusion of 120 min in Group F. The dose height assessment for both drugs is described at preliminary studies as 10 mg/kg body mass.
Ischemia was caused by laparotomic clamping the inferior aorta over renal arteries with forceps for 45 min. The clamp removal was restoring the inferior aorta patency and reperfusion. After exclusion of the blood flow, the protocol of IR was applied, as described above for each experimental group. The drugs were administered at the time of reperfusion, through inferior vena cava catheter. The ASTl was determined at 60th min of reperfusion (for A, C, and E) and 120th min of reperfusion (for Groups B, D and F). Along, a weak relation was rised between ASTl values with animals' mass (P = 0.2154), so it was no use of calculating the predicted ASTl values for the animals' mass.
Table 1 presents the (%) hypertransferasemic influence of Epo regarding reoxygenation time. Furthermore, Table 2 presents the (%) hypertransferasemic influence of U-74389G regarding reperfusion time. Chi-square tests were applied using the ratios which produced the (%) results per endpoint. The outcomes of Chi-square tests are depicted in Table 3. The statistical analysis was performed by Stata 6.0 software (Stata 6.0, StataCorp LP, Texas, USA).
The successive application of Chi-square tests revealed that U-74389G augmented the ASTl by 1.149264-fold (1.006956-1.311683) more than Epo at 1 h (P = 0.0391), by 0.9347365-fold (0.9334662-0.9360085) less than Epo at 1.5 h (P = 0.0000), by 0.6695775-fold (0.5800545-0.7729184) less than Epo at 2 h (P = 0.0000), less by 0.7631082 (0.7620376-0.7641804) (P = 0.0000) without drugs, and by 0.8224656-fold (0.8211631-0.8237701) less than Epo whether all variables have been considered (P = 0.0000).
The unique available study investigating the hypertransferasemic effect of U-74389G on ASTl was the preliminary one. Apart from the most famous activities this drug has as the neuroprotection and membrane-stabilization properties, it also accumulates in the cell membrane, protects the vascular endothelium from peroxidative damage, but hardly penetrates the blood-brain barrier. It elicits a beneficial effect in ototoxicity and Duchenne muscular dystrophy. It increases γgt, superoxide dismutase, and glutathione levels in oxygen-exposed cells. It treats septic states and acts as immunosuppressant in flap survival. It prevents the learning impairments; it delays the early synaptic transmission decay during hypoxia improving energetic state of neurons. It shows antiproliferative properties on brain cancer cells and is considered as a new promising anti-inflammatory drug for the treatment of reperfusion syndrome in IR injuries.
The same authors confirmed the short-term hypertransferasemic effect of Epo preparations in non-iron-deficient individuals. Li et al. demonstrated that EPO may play a protective role against LPS-induced multiple organ failure by reducing the inflammatory response and tissue degeneration, possibly through the phosphatidylinositol 3-kinase/AKT and NF-kB signaling pathways restoring the LPS-induced ASTl in rats. Fu et al. examined the protective effect of rHuEPO which is mediated through the activation of the phosphatidylinositol-3 kinase/AKT/endothelial nitric oxide synthase (eNOS) signaling pathway, at least in part, by increasing p-AKT and p-eNOS, and leads to the maintenance of an elevated level of NO in I/R injury of the liver. Yildar et al. investigated the protective effect of 2-aminoethyl diphenylborinate which significantly reduced the sAST in the rat kidney I/R injury group. Bayramoglu et al. examined the use of lycopene, while improvements of the AST values were partial and dose-dependent (P < 0.05) in IR injury of rat liver. Liu et al. showed that quercetin significantly reduced apoptosis rate, improved cardiac function, and decreased the levels of AST, by inhibiting apoptosis in vivo and PI3K/AKT pathway involved in the anti-apoptotic effect in SD rats in myocardial IR injuries in vivo. Bayramoglu et al. noticed that gallic acid significantly decreased the AST activities in tissue homogenates than no treatment group (P < 0.05) in oxidative stress generated by hepatic I/R-induced control rats. Matsuno et al. found the ASTl in the control versus hydrogen group in 30, 60, and 120 min after reperfusion being more by 8.9%, 9.59%, and 3.54%, respectively, in a porcine liver reperfusion injury. Saidi et al. compared the control group with animals treated with tilapia fish oil which experienced a significant decrease (P < 0.05) in ASTl in reperfusion periods in male Wistar rats subjected to warm liver IRI. Li et al. significantly ameliorated the I/R injury of the liver after Mino treatment, as shown by decreased Suzuki scores and liver function AST in male Sprague-Dawley rats liver. Ozkan et al. concluded that hypothermic reperfusion and O3 preconditioning might be beneficial in skeletal muscle IR injury since the ASTl were decreased than those in the IR group in the rats. Hu et al. found the AST activities declined (P < 0.05) in tanshinone IIA (TSA) L-TSA, M-TSA, and H-TSA rat myocardial ischemia groups. Cahova et al. indicated that metformin treatment prevented an acute stress-induced necroinflammatory reaction, reduced AST serum activity, diminished lipoperoxidation, and reduced mitochondrial performance but concomitantly protected the liver from I/R-induced injury in Wistar rats. Yildiz et al. showed a decrease in ASTl in the micronized purified flavonoid fraction-treated rats than hepatic I/R group rats (P < 0.001 for all). Zhang et al. indicated that hydrogen inhalation at 2% concentration for 1 h before liver syngeneic orthotopic transplantation protected from ischemia/reperfusion injury by activation of the NF-kB signaling pathway, reducing the sAST activities in rats. Lee et al. found hepatocytes AlbCre+/constitutively active nuclear factor (erythroid-derived 2)-like 2 (caNrf2)+ having significantly reduced serum transaminases than wild-type littermate controls in warm hepatic murine IRI. Tang et al. regarded Dioscorea nipponica Makino, D. panthaica Prain et Burkill (DP), and D. zingiberensis C.H. Wright (DZ) as having the same traditional therapeutic actions, such as TS groups exhibiting significantly reduced activities of AST than the model group (ISO injection only). Yucel et al. noticed that infliximab significantly reduced the ASTl in IR liver. Deng et al. significantly reduced the levels of AST in the MT group at each time point than that of the liver function IR group (P < 0.05) in male Sprague-Dawley rats. Lee et al. acknowledged that treatment with eupatilin significantly decreased sAST as well as liver histologic changes in acute IR-induced hepatic damage. Ozsoy et al. found remarkably higher sASTl in IR group than the sham group and the laboratory tests returned to normal levels in IR+melatonin (MEL) group after MEL treatment of the hepatic tissue. Bektas et al. found sAST significantly different in tadalafil and pentoxifylline groups than liver IR group. Younis et al. investigated the Silymarin preconditioning which decreased AST and improved hepatic architecture in HIR injury of insulin-resistant rats. Abdelsameea et al. pretreated with liraglutide which decreased AST activities with attenuation of necrosis and inflammation while enhanced Bcl-2 expression in liver IR male rats. Liu et al. shown that the formula of Guanxin Dhutong capsule which has four main active ingredients, protocatechuic acid, cryptotanshinone, borneol, and eugenol, diminished the infarct size and reduced ASTl in vivo in a rat model of the coronary artery. Hao et al. noticed that propofol significantly reduced the activities of sAST in QSG-7701 cells in vitro of hepatic I/R injury in rats. Wang et al. revealed that 2'-O-galloylhyperin effectively ameliorated CCl4-induced hepatic damage by reducing AST activities in an animal model. Saidi et al. invented that Pistacia lentiscus oil decreased both the visible severe intestinal damage and the sASTl in intestinal IR. Cai et al. pretreated with salidroside (20 mg/kg/day for 7 days, intraperitoneally) which significantly decreased sAST levels after 6 h and 24 h of reperfusion and protected the segmental (70%) warm hepatic liver against I/R-induced injury. Wang et al. found that flavonol glycosides which are in high concentrations in Inula racemosa altered cellular morphology, and cytokines and AST were returned to near normal level in hepatic I/R injury. Ardasheva et al. elevated the intra-abdominal pressure (IAP) above 20 mmHg which led to progression of abdominal compartment syndrome that is associated with organ dysfunction or failure and elevated activities of AST found in some of the experimental groups than control ones of animals not subjected to increased IAP and time frame tested for liver. Zazueta et al. found that citicoline CDP-choline reduced ASTl in blood samples from reperfused rats in I/R rat livers. Miyauchi et al. evaluated the levels of sAST as well as the scores of liver necrosis significantly lower in the antioxidative nutrient-rich enteral diet (Ao diet) group than the control diet group in liver IR mice. Zhang et al. showed that the role of hydrogen-rich saline treatment significantly decreased serum levels of AST activity and TUNEL-positive cells in miniature pig model of laparoscopic HIRI on hepatectomy. Chen et al. observed significantly decreased (all P < 0.05) the levels of AST in the rosiglitazone group than the HIRI group in a rat model of hepatic ischemia-reperfusion injury. Gholampour et al. treated with remote ischemic perconditioning and quercetin which reduced plasma AST activity in the liver after renal I/R. Brandao et al. observed separately the protective effects of allopurinol and the benefits of ischemic post-conditioning by measuring ASTl with significantly reduced I/R systemic injuries in rats.
According to above, Table 3 shows that U-74389G has 0.8224656-fold (0.8211631-0.8237701) less hypertransferasemic effect than Epo (P = 0.0000) whether all variables have been considered (P = 0.0000), a trend attenuated along time, in Epo non-deficient rats. A meta-analysis of these ratios from the same experiment, for 20 other seric variables, provides comparable results [Table 4][39,40].
The antioxidant agent U-74389G was proved having 0.8224656-fold (0.8211631-0.8237701) less hypertransferasemic effect than Epo whether all variables have been considered (P = 0.0000); a trend attenuated along the short-term time frame of the experiment in rats. A biochemical investigation remains about how U-74389G mediates in these actions.
This study was funded by Scholarship by the Experimental Research Center ELPEN Pharmaceuticals (E.R.C.E), Athens, Greece. The research facilities for this project were provided by the aforementioned institution.
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