OBJECTIVETo study the characteristics of changes of LDH enzyme patterns of mice under slight hypoxia.

METHODSMice treated with artificial hypoxia, various tissues were made for the test of LDH enzymatic activity by the specific staining technique. LDH (1-5) relative percentage enzymatic activity (RPEA) were measured with CS-910 dual-wavelength thin layer chromatography scanner.

RESULTSThe RPEA of LDH isozymes of various tissues after slight hypoxia shifted to the isozymes LDH1 and LDH2, whose principal subunits are H subunits, and the RPEA of LDH1 (H4), LDH2 (H3M) increased, while RPEA of LDH5 (M4) in various tissues decreased prominently except the cardiac muscle, and that of LDH4 (HM3) decreased as well. After polyacrylamide gel electrophoresis (PAGE) of the hypoxia treated cardiac muscle specimen was made, activity subbands originated regularly in the isoyme patterns of LDH, with the regularity of LDH1 (0 subband), LDH2 (0-1 subbands), LDH3 (0-2 subbands), LDH4 (1-3 subbands), LDH5 (2-4 subbands). After adding appropriate amount of NAD+ to the hypoxia treated cardiac muscle specimen, PAGE showed the subbands of four isoymes (LDH2-LDH5) reduced or even totally disappeared in the isozyme patterns.

CONCLUSIONSThe negative feedback regulation of coenzymization and decoenzymization of LDH isozymes is one of the mouse stress responses to slight hypoxia.

Animals ; Hindlimb ; enzymology ; Hypoxia ; enzymology ; Isoenzymes ; metabolism ; L-Lactate Dehydrogenase ; classification ; metabolism ; Liver ; enzymology ; Mice ; Muscles ; enzymology ; Myocardium ; enzymology ; Random Allocation

OBJECTIVETo explore the changes of mRNA and protein expressions of glycolytic and fatty acid metabolic enzymes early after acute myocardial ischemia.

METHODSTwelve dogs were randomly divided into 3 groups (sham, 20 min ischemia and 40 min ischemia, n = 4 each). Myocardial samples from ischemic and nonischemic zone were obtained for histology examination, and the mRNA expressions for Phosphofructokinase (PFK), Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), GLUT1, GLUT4, Medium-chain acyl-CoA dehydrogenase (MCAD) and Heart-fatty acid binding protein (H-FABP) were determined by Real Time PCR-SYBR Green RT-PCR. GLUT1 protein expression was determined by immunohistochemistry. The apoptotic cardiomyocytes was evaluated by TUNEL.

RESULTSCompared to sham hearts, H-FABP mRNA was decreased in nonischemic and ischemic zone (P < 0.05) while GLUT1 mRNA expression was significantly increased in nonischemic and ischemic zone (P < 0.05) in dogs underwent 20 and 40 min ischemia. PFK mRNA tended to be higher in ischemic myocardium (P = 0.065) and GAPDH, MCAD as well as GLUT4 remained unchanged post ischemia (all P > 0.05). Positive GLUT1 protein staining was visualized in ischemic myocardium of hearts underwent 20 and 40 min ischemia. The myocardial apoptosis cells was 6.4% +/- 0.9% in sham hearts, 28.0% +/- 3.7% in hearts underwent 20 min ischemia (P < 0.05 vs. sham) and 38.4% +/- 1.9% in hearts underwent 40 min ischemia (P < 0.05 vs. sham).

CONCLUSIONSSignificant down and up-regulated glycolytic and fatty acid metabolic enzymes early after myocardial ischemia suggested that these enzymes might play an important role in acute myocardial ischemia.

Animals ; Disease Models, Animal ; Dogs ; Fatty Acids ; metabolism ; Glycolysis ; Myocardial Ischemia ; enzymology ; Myocardium ; enzymology ; RNA, Messenger ; genetics

Acute myocardial infarction is one of the major causes of mortality worldwide. Reperfusion in a timely fashion is the most effective way to limit infarct size. However, reperfusion can itself prompt further myocardial injury. This phenomenon is commonly known as myocardial ischemia-reperfusion (IR) injury. Mitochondrial aldehyde dehydrogenase (ALDH2) is an enzyme metabolizing acetaldehyde and toxic aldehydes. Increasing evidence has revealed a cardioprotective role of ALDH2 in myocardial IR injury. Evidence from animal studies has shown that ALDH2 diminishes acute myocardial infarct size, ameliorates cardiac dysfunction and prevents reperfusion arrhythmias. The activity of ALDH2 is severely compromised if it is encoded by the mutant ALDH2*2 gene, with an incidence of approximately 40% in Asian populations. Epidemiological surveys in the Asian population have depicted that ALDH2 polymorphism is closely associated with higher prevalence of acute myocardial infarction and coronary artery disease. Therefore, targeting ALDH2 may represent a promising avenue to protect against IR injury. This review recapitulates the underlying mechanisms involved in the protective effect of ALDH2 in cardiac IR injury. Translational potential of ALDH2 in the management of coronary heart disease is also discussed.
Aldehyde Dehydrogenase ; metabolism ; Animals ; Heart ; physiopathology ; Humans ; Mitochondria, Heart ; enzymology ; Myocardial Reperfusion Injury ; Myocardium ; pathology

Objective: To explore the value of paraquat (PQ) intake, urine protein and myocardial enzyme indexes in judging the prognosis of patients with acute PQ poisoning. Methods: From September to December 2021, all 201 patients with acute PQ poisoning admitted to Guangzhou Twelfth People's Hospital from January 2010 to December 2019 were selected as the research objects. Based on follow-up results 60 days after poisoning, the research objects were divided into survival group (n=78) and death group (n=123) . The differences in information about poisoning, treatment plan, PQ intake, urine protein, creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase, and α-hydroxybutyrate dehydrogenase between the two groups of patients were compared and analyzed. Logistic regression and Cox regression were used to analyze the correlation between poisoning outcome and PQ intake, urine protein and myocardial enzymes. ROC curve and principal component analysis were used to explore high-efficiency indicators for predicting the outcome of acute PQ poisoning. Results: The PQ intake[50 (20, 100) ml], urine protein (total rank 15570.50) , creatine kinase[ (336.36±261.96) U/L], creatine kinase isoenzyme[ (43.91±43.74) U/L], lactate dehydrogenase [ (346.01±196.50) U/L], α-hydroxybutyrate dehydrogenase content[ (271.23±11.92) U/L] of patients in the death group were all higher than the survival group[15 (10, 20) ml, 4730.50, (187.78±178.06) U/L, (18.88±15.50) U/L, (190.92±60.50) U/L, (152.60±48.34) U/L, respectively] (P<0.05) . The outcome of acute PQ poisoning was positively correlated with PQ intake, urine protein, creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase, and α-hydroxybutyrate dehydrogenase (P<0.05) . Multivariate logistic regression and multivariate Cox regression analysis showed that creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase and α-hydroxybutyrate dehydrogenase was positively correlated with the prognosis of patients with acute PQ poisoning (P<0.05) . ROC curve analysis and principal component analysis showed that the combined indexes of PQ intake, urine protein and myocardial enzymes had the highest efficacy and weight in judging the prognosis of patients (AUC=0.91, weight coefficient=0.19, sensitivity=0.76, specificity=0.89) . When the combined score was ≥4, the probability of accurately predicting the death of patients was as high as 91% (positive predictive value=0.91) . Conclusion: PQ intake, urine protein combined with creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase, and α-hydroxybutyrate dehydrogenase has high value in predicting the prognosis of patients with acute PQ poisoning.
Humans ; Creatine ; Creatine Kinase ; Isoenzymes ; Lactate Dehydrogenases ; Paraquat/poisoning* ; Prognosis ; Retrospective Studies ; Myocardium/enzymology* ; Urine/chemistry*

The purpose of the present study was to investigate whether interleukin-2 (IL-2) changes the activity of sarcoplasmic reticulum (SR) Ca(2+) ATPase, sarcolemmal Ca(2+)ATPase and Na(+)/K(+) ATPase by measuring the Pi liberated from ATP hydrolysis with colorimetrical methods. It was shown that the activity of Ca(2+)ATPase in SR from IL-2-perfused (10, 40, 200, 800 U/ml) rat heart increased dose-dependently. After incubation of the SR with ATP (0.1 approximately 4 mmol/L), the activity of SR Ca(2+)ATPase increased dose-dependently in the control group. In the SR from 200 U/ml IL-2-perfused hearts, the activity of Ca(2+)ATPase was much higher than that in the control group. On the other hand, incubation of the SR with Ca(2+) (1 approximately 40 micromol/L) increased the activity of SR Ca(2+) ATPase in the control group. The activity of SR Ca(2+)ATPase of IL-2-perfused hearts was inhibited as the function to Ca(2+). Pretreatment with specific kappa-opioid receptor antagonist nor-BNI (10 nmol/L) for 5 min attenuated the effect of IL-2 (200 U/ml) on the activity of SR Ca(2+) ATPase. After pretreatment with pertussis toxin (PTX, 5 mg/L) or U73122 (5 micromol/L), IL-2 failed to increase SR Ca(2+)ATPase activity. The activity of SR Ca(2+)ATPase was not changed by incubation of SR isolated from normal hearts with IL-2. Perfusion of rat heart with IL-2 did not affect the activity of sarcolemmal Ca(2+)ATPase and Na(+)/K(+)ATPase. It is concluded that perfusion of rat heart with IL-2 increases the activity of SR Ca(2+)ATPase dose-dependently, which is mainly mediated by cardiac kappa-opioid receptor pathway including a PTX sensitive Gi-protein and phospholipase C. IL-2 increases the activity of SR Ca(2+)ATPase as the function to ATP, but inhibits the activity of SR Ca(2+)ATPase as the function to Ca(2+). IL-2 has no effect on the activity of sarcolemmal Ca(2+)ATPase and Na(+)/K(+)ATPase.
Animals ; Interleukin-2 ; pharmacology ; Male ; Myocardium ; enzymology ; Rats ; Rats, Sprague-Dawley ; Sarcolemma ; enzymology ; Sarcoplasmic Reticulum ; enzymology ; Sarcoplasmic Reticulum Calcium-Transporting ATPases ; metabolism ; Sodium-Potassium-Exchanging ATPase ; metabolism

OBJECTIVETo evaluate the expression of nitric oxide synthase III (NOS III) mRNA in the heart, aorta, kidney and liver of spontaneously hypertensive rats (SHR).

METHODSTwo hundred and ninety-four total RNA samples were obtained from the tissues of ventricle, aortic smooth muscle, kidney and liver of SHR and normotensive rats (Wistar-Kyoto rats, WKY). RNA array was used to determine the mRNA levels of NOS III of the two groups.

RESULTSCompared with WKY, the systolic blood pressure increased significantly in SHR at 6-week-old, 8-week-old, 10-week-old and 12-week-old [(158.50 +/-7.69 vs 108.67 +/-5.89) mmHg, (174.33 +/-4.46 vs 128.50 +/-4.97) mmHg, (198.00 +/-13.45 vs 142.00 +/-3.58) mmHg, (216.67 +/-8.91 vs 141.17 +/-4.92) mmHg, P<0.01], and the ventricle/body weight ratio was significant higher at 10-week-old and 12-week-old [(4.08 +/-0.17 vs 3.59 +/-0.11, 4.05 +/-0.18 vs 3.40 +/-0.19)mg/g, P<0.01]. In the heart tissue and the kidney, the mRNA levels of NOS III were significantly increased at 6-week-old, 8-week-old, 10-week-old and 12-week-old (1.12 +/-0.18 vs 0.90 +/- 0.15, 1.46 +/- 0.34 vs 1.06 +/-0.18, 1.66 +/- 0.31 vs 1.21 +/- 0.30, 1.98 +/- 0.40 vs 1.31 +/-0.38, P <0.05) and at 4-week-old, 6-week-old, 8-week-old, 10-week-old and 12-week-old (1.10 +/- 0.21 vs 0.81 +/-0.11, 1.28 +/-0.18 vs 0.95 +/-0.13,1.31 +/-0.23 vs 0.99 +/-0.23, 1.70 +/-0.30 vs 1.08 +/-0.25, 1.83 +/-0.33 vs 1.15 +/-0.20, P<0.05 or P<0.01), respectively. There was no significant difference of the NOS III expression in the liver and no significant signals were detected in the aortic smooth muscle.

CONCLUSIONThe results provide the evidence of the increased expression of NOS III in different tissues in SHR and suggests the progressive nature of essential hypertension.

Animals ; Hypertension ; enzymology ; genetics ; Kidney ; enzymology ; Liver ; enzymology ; Male ; Myocardium ; enzymology ; Nitric Oxide Synthase ; biosynthesis ; genetics ; Nitric Oxide Synthase Type III ; Oligonucleotide Array Sequence Analysis ; methods ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Carbon Monoxide Poisoning ; enzymology ; Case-Control Studies ; Female ; Humans ; Male ; Middle Aged ; Myocardium ; enzymology ; Young Adult

OBJECTIVETo explore the effect of irbesartan on angiotensin-converting enzyme 2 (ACE2) mRNA expression in diabetic rat myocardium.

METHODSThirty 8-week-old male Wistar rats were randomly divided into control group (n=7), diabetic model group (n=14) and irbesartan group (n=9). Diabetes was induced by a single intraperitoneal injection of STZ (55 mg/kg), a blood glucose>16.7 mmol/L 72 h after the injection indicated successful establishment of diabetes. Four weeks after the modeling, the rats in irbesartan group were given 50 mg/kg irbesartan. ELISA was used to measure myocardial AngII content in the rats, and myocardial ACE2 mRNA expression was determined by real-time PCR.

RESULTSMyocardial AngII level in the diabetic model group was significantly higher than that in the control group (P<0.001). Irbesartan administration significantly lowered cardiac AngII levels in the diabetic rats (P<0.001). The rats in irbesartan group showed significantly increased myocardial ACE2 mRNA expression compared with those in the control and diabetic rat groups (P<0.05).

CONCLUSIONIrbesartan can increase ACE2 mRNA expression in the myocardium, which might be one of the mechanisms underlying its effect in improving the cardiac function in diabetic rats.

Animals ; Biphenyl Compounds ; pharmacology ; Diabetes Mellitus, Experimental ; enzymology ; Male ; Myocardium ; enzymology ; Peptidyl-Dipeptidase A ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Tetrazoles ; pharmacology

Acute Disease ; Carbon Monoxide Poisoning ; enzymology ; physiopathology ; Creatine Kinase ; metabolism ; Creatine Kinase, MB Form ; Echocardiography ; Heart ; physiopathology ; Humans ; Hyperbaric Oxygenation ; Isoenzymes ; metabolism ; Myocardium ; enzymology

OBJECTIVETo investigate whether acute lung injury (ALI) and changes of myocardial ATP enzymes were induced by intravenous or intraventricle of left heart injection of lipopolysaccharide (LPS) in aging rats.

METHODS40 male Wistar rats were used for reproducing aging animal model. Aging rats were randomly divided into aging control group (n = 8), ALI group (LPS, 5 mg/kg body weight intravenous injection, n = 16), and LPS group (same dosage LPS, intraventricle of left heart injection, n = 16). The samples (blood, lung and heart) were collected at 2, 6 hours after LPS or saline administration.

RESULTSCompared with aging control, protein content in bronchial alveolar lavage fluid (BALF), ratio of lung wet/dry weight and the LA, NO2-/NO3- and MDA contents in blood were increased markedly (P < 0.01) at 2, 6 hours in ALI group. The GSH-Px, Na(+)-K(+)-ATPase activities in lung tissue were decreased significantly (P < 0.01), but NO2-/NO3- content in lung tissue was increased obviously (P < 0.01) at 2 hours in ALI group. These changes were maintained until at 6 hours after LPS administration. The above parameters were no obviously changes in myocardium at 2 hours after LPS administration in ALI group. But at 6 hours, MDA content was increased obviously (P < 0.01); Na(+)-K(+)-ATPase, Ca(2+)-Mg(2+)-ATPase and GSH-Px activities in myocardium were decreased markedly (P < 0.01). While in LPS group, only NO2-/NO3- contents were increased (P < 0.05) in blood and lung tissue as well as Na(+)-K(+)-ATPase activity in lung tissue were decreased (P < 0.05), another parameters had no obvious changes.

CONCLUSIONSALI was obviously formed by intravenous injection LPS after 2, 6 hours in aging rats. Myocardial enzyme etc decreased only at 6 hours in ALI group. But above parameters were no obviously changes in LPS group. It was suggested that there was probable myocardial damage in rats of ALI group, and it was mainly induced by ALI.

Aging ; Animals ; Glutathione Peroxidase ; metabolism ; Lipopolysaccharides ; Male ; Myocardium ; enzymology ; Rats ; Rats, Wistar ; Respiratory Distress Syndrome, Adult ; chemically induced ; enzymology ; Sodium-Potassium-Exchanging ATPase ; metabolism