Creatine Kinase Enzyme Activity Research Articles

Relationship of CK-MB Levels with Troponin T in Patient with Coronary Heart Disease at Siloam Hospital Jambi

Background: Coronary heart disease (CHD) is one of the cardiovascular diseases which is the highest cause of death in the world. CHD occurs due to the build-up of cholesterol plaque which causes narrowing of the arteries. CHD is characterized by an increase in biomarkers, especially cardiac troponin and Creatine Kinase enzyme activity. The aim of this research is to determine the relationship between CK-MB and Troponin T in CHD patients.
 Method: The type of this research is descriptive study with a cross sectional approach. The population of this study was all patients who had been clinically diagnosed with CHD by doctors at Siloam Jambi Hospital according to their medical records. The sampling technique used was a total sample technique that met the inclusion and exclusion criteria. To analyze the relationship between variables, a parametric statistical test is used, namely the Pearson correlation test.
 Result: The results of the study show the average value of CK-MB activity = 46.12 IU/L and Troponin T = 359.53 ng/L. The Pearson correlation test analysis showed that there was a significant relationship between CK-MB and Troponin T (p <0.00001), and the correlation coefficient (r) is 0.636.
 Conclusion: The activity of the CK-MB enzyme and the levels of Troponin T enzymes have a strong relationship in CHD patients at Siloam Hospital Jambi.

Application of enzymatically treated Artemisia annua L. on adult grass carp (Ctenopharyngodon idella): Improved growth performance, intestinal antioxidant capacity and apical junctional complex

The present study evaluated the effects of enzymatically treated Artemisia annua L. (EA) on the growth performance, intestinal antioxidant capacity, and apical junctional complex (AJC) of adult grass carp. In this experiment, 375 healthy grass carp (initial body weight 673.96 ± 1.24 g) were selected and randomly divided into 5 treatments, and fish in each group were fed diets with different levels of EA (0, 400, 800, 1200, and 1600 mg/kg) 9 weeks. The results showed that compared with the control group (0 mg/kg EA diet), the EA supplementation in the diet increased the percentage of weight gain (PWG), specific growth rate (SGR), and feed intake (FI) (P < 0.05), indicating that dietary EA supplementation improved the growth performance of adult grass carp. The dietary EA supplementation also enhanced the digestion and absorption ability of adult grass carp, which might be reflected by improving the activities of hepatopancreas digestive enzymes (trypsin, chymotrypsin, lipase, and amylase) and intestinal brush border enzymes (alkaline phosphatase, Na+/K+-ATPase, and γ-glutamyl transpeptidase), but EA did not affect the creatine kinase enzyme activity. Meanwhile, we explored the effect of dietary EA addition on the structural integrity of the grass carp intestine. We observed that dietary EA supplementation improved the antioxidant capacity of the intestine which be reflected by increasing the activities levels of superoxide dismutase (SOD) and catalase (CAT), which might be related to the binding protein Keap1a (not Keap1b)/ NF-E2-related factor-2 (Nrf2) signaling pathway. In addition, dietary EA supplementation enhanced the integrity of AJC by increasing the mRNA levels of intestinal tight junction proteins (TJs) (except claudin 11, claudin 12, claudin 15a) and adhere junction proteins (AJs) (E-cadherin, α-catenin, β-catenin, nectin, and afadin), which might be related to the Rho family GTPases (RhoA)/ Rho-associated protein kinase (ROCK)/ myosin light chain kinase (MLCK) signaling pathway. Collectively, dietary EA supplementation improved growth performance, digestion and absorption ability, and intestinal structural integrity in grass carp, which were associated with the activation of related signaling pathways and regulatory factors. Finally, by the growth indicator percent weight gain (PWG) and intestinal oxidative damage index protein carbonyl (PC), the optimum amounts of EA supplementation of adult grass carp (673–1726 g) were assessed to be 808.09 and 730.38 mg/kg diet, respectively.

Stress responses in camels subjected to different rest periods (0 and 12 h) at slaughterhouse

This study investigated the effect of two different rest periods (R0: no rest time, and R12: 12 h of rest) on several stress indicators, including plasma and serum stress parameters, in dromedary camels (Camelus dromedarius). This study involved 60 healthy male dromedary camels aged 5 years, from which blood samples were collected. Cortisol, glucose, urea, creatinine, the enzymatic activity of creatine kinase, lactic dehydrogenase, aspartate aminotransferase, alanine aminotransferase, and alkalinephosphatase were analyzed. Data obtained indicated that rest time had a significant effect on cortisol, creatinine, creatine kinase, lactic dehydrogenase and aspartate aminotransferase (p < 0.05). However, no statistically significant effect was found for glucose, urea, alanine aminotransferase, and alkalinephosphatase. The values of cortisol and creatinine showed a significant decrease at R12. In contrast, the enzymatic activity of creatine kinase, lactic dehydrogenase, and aspartate aminotransferase, significantly increased at R12. Additionally, several correlations between different studied parameters were documented, including for lactic dehydrogenase. The results obtained in this study suggest that rest time may influence welfare indicating parameters. In summary, a rest time of more than 12 h is recommended in order to allow camels to recover from the effects of pre-slaughter stress. Additionally, lactate dehydrogenase might be suitable to use as an indicator of stress in camels during the slaughter process.

The role of whey protein in myogenic differentiation

Whey protein has been shown to prevent exercise-induced protein degradation and muscle damage. We hypothesized that whey protein would regulate muscle cell differentiation. Adding various concentrations of whey protein to C2C12 myoblasts induced cell differentiation and MyoD (myogenic differentiation protein) expression as well as the phosphorylation of AKT (protein kinase B). Whey protein-induced differentiation-specific markers increased the enzymatic activities of creatine kinase and citrate synthase and the expression of muscle-specific microRNA. Whey protein elevated AKT phosphorylation on Thr308 and Ser473, which was inhibited by LY294002 (a non-selective phosphoinositide 3-kinases inhibitor), suggesting that whey protein acts via PI3K (phosphatidylinositol 3-kinase). Blocking of the PI3K/AKT pathway with specific inhibitors revealed its requirement in mediating the promotive effects of whey protein on C2C12 cell differentiation. These effects of whey protein on myoblast differentiation suggest its positive influence in preventing muscle atrophy.

Molecular Investigations of the Effect of Thermal Manipulation During Embryogenesis on the Enzymatic Activity of Creatine Kinase and Lactate Dehydrogenase in Broiler Muscle

Incubating temperature and timing or duration is critical to determine the optimum protocol of thermal manipulation (TM), which underlines muscle growth improvement. Therefore, the aim of the present study is to determine the optimum period of embryonic TM that may result in the improvement of pectoral and thigh muscle myogenesis. This is done by investigating the level of mRNA expression of creatine kinase (CK) and lactate dehydrogenase (LDH). An additional goal is measuring the blood levels of CK and LDH as a biomarker of muscle injury due to the experimental thermal challenge on post-hatch day 35. The study was conducted on 1,440 fertile eggs (Ross broilers) that were divided randomly and equally into a control group and four treatment groups (TM1, TM2, TM3, and TM4). The treatment groups were daily subjected to TM at 39 ºC for 18h with 65% relative humidity (RH) during embryonic days (EDs) 7-11, 11-15, 15-18, and 7-18, respectively. Among the thermally manipulated groups that were investigated, TM1 (ED 7-11) resulted in significant improvement of mRNA expression and enzymatic concentration of CK and LDH in muscle during embryogenesis, as compared to the control. Six hours of TC showed the highest significant CK and LDH expression and concentration levels in the control as compared to TM groups. Thus, the results of this study indicate that TM during ED 7-11 improves pectoral and thigh muscles’ response to heat stress without adversely affecting their performance. This finding could be used by commercial breeders to enhance local broiler production.

The Effect of the Repair of Induced Articular Cartilage Defects in Pigs Using Calcium Phosphate Cement with Aminoacids on the Concentrations of Selected Inflammatory Markers and Serum Enzyme Activities

The repair of articular cartilage defects is an intensively developing area of research. Severe inflammatory reactions after surgical interventions on bones or their structures may lead to changes of bone or joint asymmetry. In laboratory diagnostics, some inflammatory biomarkers and serum enzymes are available for the evaluation of these inflammatory processes. A general understanding of inflammatory responses following the repair of cartilage defects is still lacking. The aim of this study was to describe the alterations in the values of five inflammatory markers and the activities of several enzymes in seven 5-month-old pigs within the first 30 days following the restoration of induced articular cartilage defects using the tetracalcium phosphate/nanomoneite cement powder enriched with amino acids (CAL). The reconstruction of surgically induced defects was accompanied by a significant increase of serum amyloid A (SAA, p &lt; 0.05), haptoglobin (Hp, p &lt; 0.001), C-reactive protein (CRP, p &lt; 0.01), and pig major acute phase protein (pig-MAP, p &lt; 0.001). Their concentrations decreased gradually within one-month post-surgery, the values recorded at the end of this period were higher than those obtained prior to surgery. The concentrations of α1-acid glycoprotein (AGP) showed no significant changes during the evaluated period. Alterations were also found in the enzyme activities of creatine kinase (p &lt; 0.05), lactate-dehydrogenase and alkaline phosphatase (p &lt; 0.01). These findings suggest that SAA, Hp, CRP and pig-MAP might be applicable biomarkers of acute phase response for the monitoring of postoperative period.

Effects of horse housing on musculoskeletal system post-exercise recovery

This study examined the effects of two housing systems (control housing and loose housing) on musculoskeletal condition during recovery from race-like exercise in Standardbred horses. The hypothesis was that a loose housing system provides better conditions for musculoskeletal recovery than the control housing. Eight adult geldings (mean age 11 years) were used in a study with a cross-over design, with the control housing (CH) and loose housing (LH) treatments each run for 21 days. The horses had ad libitum access to forage and performed two similar race-like exercise tests (ET), on day 7 and day 14 in each treatment. Blood samples were collected before ET, at finish line, and at 7, 22, and 44 h of recovery and analysed for the muscle enzyme activities of creatine kinase and amino transferase. Before and three days after ET, hind leg fetlock joint region circumference and diameter, joint range of motion in right hock and carpus, mechanical nociceptive threshold in back muscle, and movement asymmetry were recorded. Overall circumference and overall diameter of hind fetlock joint region were lower in LH horses than CH horses (P=0.045 and P=0.017, respectively), but no other differences were observed. In conclusion, a loose housing system did not alter the recovery of musculoskeletal condition other than preventing a post exercise enlargement of the circumference and diameter of the hind fetlock joint region.

FNDC5 expression closely correlates with muscle fiber types in porcine longissimus dorsi muscle and regulates myosin heavy chains (MyHCs) mRNA expression in C2C12 cells.

BackgroundIrisin (a glycosylated protein) is cleaved from fibronectin type III domain-containing protein 5 (FNDC5), which is expressed mainly in animal muscle tissues and has multiple metabolic regulatory activities. However, their roles in controlling myofiber types in skeletal muscle remain unclear.MethodologyTwo different commercial hybridized pigs, LJH (a crossed pig containing Chinese native pig genotypes) and DLY (Duroc × Landrace × Yorkshire) were selected to analyze FNDC5 mRNA expression and the mRNA composition of four adult myosin heavy chain (MyHC) isoforms (IIIaIIxIIb) in the longissimus dorsi (LD) muscle. C2C12 myoblasts were cultured to investigate the effects of FNDC5 on the four MyHCs mRNA expressive levels, using small interfering RNA for depletion and a eukaryotic expression vector carrying FNDC5 for overexpression. ZLN005 (a small molecule activator of FNDC5’s upstream control gene PGC1α) or recombinant human irisin protein were also used.ResultsIn LD muscle, LJH pigs had the higher FNDC5 mRNA level, and MyHC I or IIa proportion than DLY pigs (P < 0.05). For C2C12 cells in vitro, small interfering RNA (si-592) silencing of FNDC5 expression markedly reduced MyHC IIa mRNA levels (P < 0.05), while FNDC5 overexpression significantly increased MyHC IIa mRNA levels (P < 0.05). Exogenous irisin increased the mRNA levels of PGC1α (peroxisome proliferator-activated receptor gamma coactivator 1-alpha), FNDC5, MyHCI, MyHCIIa, NRF1 (nuclear respiratory factor 1), VEGF (vascular endothelial growth factor), and TFAM (mitochondrial transcription factor A,) (P < 0.05), and the enzyme activities of SDH (succinate dehydrogenase), CK (creatine kinase), and MDH (malate dehydrogenase) in C2C12 myotubes (P < 0.05). These results showed that FNDC5 mRNA expression had a significant association with the characteristics of myofiber types in porcine muscle, and participated in regulating MyHCs mRNA expression of C2C12 myogenic differentiation cells in vitro. FNDC5 could be an important factor to control muscle fiber types, which provides a new direction to investigate pork quality via muscle fiber characteristics.

The effects of active vs. passive recovery on riding performance during a simulated motocross race

Aims: Motocross consists of two races of 30 min with a break in between. Recovery between races is paramount to performance, this study aimed to compare the effects of active and passive recovery between motocross races on riding performance. Methods: Thirteen elite and non-elite racers performed two races of 30 min with 1 h break, twice with two-week interval. Between the races active (20 min ergometer cycling at 60% of HRmax) or passive recovery (no activity) were executed in a randomized order. Lap times, heart rate during riding, blood lactate, reaction time, handgrip strength, upper back pull strength, counter movement jump height, and medicine ball throw distance were measured before and after both races. Serum creatine kinase enzyme activity and strength tests were assessed also 24 h after the races. Results: No statistically significant differences were observed in any variables between protocols. A significant drop in handgrip strength was found post-race values (p < 0.001). Post-racing creatine kinase values were above resting levels. Conclusion: These results do not support the use of active recovery in between motocross races for restoration of neuromuscular or riding performance. Motocross seems to cause some exercise-induced muscle damage; thus, some rest is required to recover homeostasis.

Moringa oleifera leaf extract influences oxidative metabolism in C2C12 myotubes through SIRT1-PPARα pathway

BackgroundMoringa oleifera is an important traditional multipurpose plant, due to the presence of many bioactive compounds. Moringa oleifera leaf extracts (MOLE) have been shown to have many beneficial properties in pathological conditions including diabete. However, the lack of information about its exact molecular mechanism of action might hinder other potential use in different areas such as skeletal muscle physiology. Hypothesis/purposeSkeletal muscle represents about 40-50% of the total mass of a lean individual and is an insulin-sensitive tissue with wide variations in energy requirements. We aimed to test the effects of MOLE on oxidative metabolism and the molecular mechanism involved on myotubes by using C2C12 cell line, a well known model for in vitro skeletal muscle studies. Study designC2C12 myotubes were treated with MOLE at different working solutions for 24 and 48 hours and then culture media and cellular extracts were collected. MOLE was screened for phytochemicals determination. MethodsGlucose and free fatty acids consumption along with lactate release were assessed in the culture media. Citrate sinthase, 3-hydroxy acylCoA dehydrogenase, alanine transglutaminase and creatine kinase enzyme activities, as well as the metabolic regulatory SIRT1 and PPARα protein levels were evaluated in cellular extracts. ResultsMOLE administration induced a dose and time dependent increase in substrates consumption accompanied by an increase in intracellular oxidative metabolism enzymatic activity levels. The extracts were also able to modulate positively the protein expression of SIRT1 and PPARα. ConclusionAltogether, these data indicate that MOLE could represent a valid nutritional support for improving skeletal muscle metabolism: in fact MOLE treatment increased oxidative energy metabolism and possibly favours mitochondrial biogenesis through SIRT1/PPARα pathway. future studies will clarify wether Moringa oleifera leaf extracts consumption may be useful to improve physical performance and metabolic-related skeletal muscle diseases.

Hematological And Biochemical Blood Changes In Chronic Tendinitis Thoroughbred Race Horses

Tendon injury is the most important veterinary reason for wastage of thoroughbred racehorses. Clinical diagnosis of tendon injuries is confirmed by a combination of clinical, ultrasonographic or post mortem examination of the injured limb. In addition, measurement of hematological and biochemical blood parameters are an important tool that aid health assessment and decision-making in diagnosis, treatment and follow-up of the injured tendon. Therefore, the lack of information or misinterpretation of these parameters may affect the accuracy of disease diagnosis and then lead to poor treatment. The present study was conducted to evaluate the levels of some hematological and biochemical parameter in the blood of thoroughbred horses affected by chronic tendinitis and compared with normal horses. Blood samples were collected from 15 healthy thoroughbred horses (8 stallions and 7 mares) and 21 tendinitis thoroughbred horses (11 stallions and 10 mares); and the levels of 18 blood parameters were determined. The tendinitis horses had higher number of erythrocytes and thrombocytes, higher values of packed cell volume (PCV) and mean corpuscular volume (MCV); lower enzyme activity of creatine kinase (CK), lower values of lactic acid (LA), icteric index and mean corpuscular hemoglobin concentration (MCHC) and lower numbers of band neutrophils than the normal horses. The chronic tendinitis mares had higher number of thrombocytes and lower values of lactate dehydrogenase (LDH) enzyme activity, lactic acid, plasma proteins, MCHC and lower numbers of white blood cells (WBC) than the normal mares. The chronic tendinitis stallions had higher levels of lactic acid, plasma proteins, MCV, and higher numbers of erythrocytes and thrombocytes,; and lower values of icteric jaundice, MCHC, band neutrophils than the normal horses. No significant differences were reported when tendinitis mares were compared with tendinitis males. However, normal mares showed higher levels of plasma proteins than normal stallions. The results obtained by this study can be used as useful index to diagnose and treat chronic tendinitis in horses.

Analysis of seminal plasma biochemical parameters and sperm cryostability in different age groups of stallions

We studied sperm of stallions of different age groups of the Arab breed at the age of 4 to 21 (n=36). The concentrations of total protein (TP), albumin, globulins, glucose, urea, phospholipids, ionized calcium (Ca2+), and enzyme activity of creatine kinase (CK), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), amylase, lactate dehydrogenase (LDH) were determined in seminal plasma. After sperm freezing and thawing the progressive sperm motility and viability at +4 °C were studied. We found that progressive motility and viability of spermatozoa after freezing and thawing in stallions at the age of 6-10 years was statistically significantly higher than that of stallions at the age of 4-5 (p=0.004 and p=0.02), 11-15 (p=0.04 and p=0.04) and 16-21 (p=0.01 and p=0.01, respectively). The concentration of sperm in the ejaculates of older stallions (16-21 years old) is significantly lower than in the ejaculates of stallions aged 4-5 (p=0.04), 6-10 (p=0.003), 11-15 (p=0.04). The level of urea in seminal plasma of older stallions (16-21 years old) was statistically significantly higher than in the group of stallions aged 6-10 (p=0.01). There is a negative correlation between progressive sperm motility after cryopreservation and urea concentration in stallion seminal plasma (r=-0.48; p<0.05).

Involvement of the phosphoryl transfer network on cardiac energetic metabolism during Staphylococcus aureus infection and its association to disease pathophysiology

Evidences have suggested that the phosphoryl transfer network by the enzymatic activities of creatine kinase (CK), adenylate kinase (AK), pyruvate kinase (PK), and lactate dehydrogenase (LDH), shows new perspectives to understand some disturbances in the energy metabolism during bacterial infections. Thus, the aim of this study was to evaluate whether Staphylococcus aureus infection in mice could alter serum and cardiac activities of these enzymes and their association to disease pathophysiology. For that, we measured total leukocytes, lymphocytes and neutrophils (just 48 h of infection) that were lower in infected animals after 48 and 72 h in infected mice compared with negative control, while total protein and globulin plasma levels were higher after 72 h of infection. The serum CK activity was higher in infected animals 48 and 72 h post-infection compared to the control group, as well as observed for mitochondrial cardiac CK activity. The serum PK activity was higher in infected animals after 72 h of infection compared to the control group, and lower in the cardiac tissue. The cardiac AK activity was lower in infected animals 48 h and 72 h post-infection compared to the control group, while serum and cardiac LDH activities were higher. Based on these evidences, it is possible to conclude that the stimulation of CK activity exerts a key role as an attempt to maintain the bioenergetic homeostasis by the production of phosphocreatine to avoid a rapid fall on the concentrations of total adenosine triphosphate. In summary, the phosphoryl transfer network can be considered a pathway involved in the improvement on tissue and cellular energy homeostasis of S. aureus-infected mice.

Characterization of a Blood Spot Creatine Kinase Skeletal Muscle Isoform Immunoassay for High-Throughput Newborn Screening of Duchenne Muscular Dystrophy.

Duchenne muscular dystrophy (DMD) is a progressive, lethal X-linked neuromuscular disorder with an average worldwide incidence of 1:5000. Blood spot creatine kinase (CK) enzyme assays previously used in newborn screening programs for DMD are nonspecific because measured CK enzyme activity is attributable to 3 isoenzyme forms of CK (CK-MM, CK-MB, and CK-BB) and it is the CK-MM isoform that is found predominantly in skeletal muscle. CK-MM is increased in boys with DMD owing to muscle damage. We describe a sensitive and specific automated immunoassay for CK-MM to screen for DMD in blood spots. The prototype assay was developed on the PerkinElmer GSP® analyzer to enable high-throughput screening. CK-MM was assayed using a solid phase, 2-site immunofluorometric system. Purified human CK-MM was used to create calibrators and controls. The limit of blank (LOB), detection (LOD), and quantification (LOQ) values were <1, 3, and 8 ng/mL, respectively. The analytical measurement range was 4-8840 ng/mL. Interassay (n = 40) imprecision was <7% across the analytical range. Cross-reactivity was <5% for CK-MB and 0% for CK-BB. The mean recovery of CK-MM was 101% (range 87%-111%). Blood spots from newborn infants (n = 277) had a mean CK-MM concentration of 155 ng/mL and a 99th centile of 563 ng/mL. The mean blood spot CK-MM concentration from 10 cases of DMD was 5458 ng/mL (range 1217-9917 ng/mL). CK-MM can be reliably quantified in blood spots. The development of this CK-MM assay on a commercial immunoassay analyzer would enable standardized and high-throughput newborn blood spot screening of DMD.

A membrane-associated adenylate cyclase modulates lactate dehydrogenase and creatine kinase activities required for bull sperm capacitation induced by hyaluronic acid

Hyaluronic acid, as well as heparin, is a glycosaminoglycan present in the female genital tract of cattle. The aim of this study was to evaluate oxidative metabolism and intracellular signals mediated by a membrane-associated adenylate cyclase (mAC), in sperm capacitation with hyaluronic acid and heparin, in cryopreserved bull sperm. The mAC inhibitor, 2′,5′-dideoxyadenosine, was used in the present study. Lactate dehydrogenase (LDH) and creatine kinase (CK) activities and lactate concentration were determined spectrophotometrically in the incubation medium. Capacitation and acrosome reaction were evaluated by chlortetracycline technique, while plasma membrane and acrosome integrity were determined by trypan blue stain/differential interference contrast microscopy. Heparin capacitated samples had a significant decrease in LDH and CK activities, while in hyaluronic acid capacitated samples LDH and CK activities both increased compared to control samples, in heparin and hyaluronic acid capacitation conditions, respectively. A significant increase in lactate concentration in the incubation medium occurred in hyaluronic acid-treated sperm samples compared to heparin treatment, indicating this energetic metabolite is produced during capacitation. The LDH and CK enzyme activities and lactate concentrations in the incubation medium were decreased with 2′,5′-dideoxyadenosine treatment in hyaluronic acid samples. The mAC inhibitor significantly inhibited heparin-induced capacitation of sperm cells, but did not completely inhibit hyaluronic acid capacitation. Therefore, hyaluronic acid and heparin are physiological glycosaminoglycans capable of inducing in vitro capacitation in cryopreserved bull sperm, stimulating different enzymatic pathways and intracellular signals modulated by a mAC. Hyaluronic acid induces sperm capacitation involving LDH and CK activities, thereby reducing oxidative metabolism, and this process is mediated by mAC.

The pharmacologically active components of oxytropis falcata bungereduce ischemic-reperfusion injury in the rat heart

Oxytropis falcata is used as the main material to prepare various Tibetan traditional medicine, which its activity was reported that anti-inflammation and analgesia. Flavonoids is the chemical basis for the anti-inflammatory and anti-oxidant efficacy. The influence of total flavonoids of Tibetan herb O. falcata on myocardial ischemic-reperfusion injury was investigated using ethanol, chloroform, and ethyl acetate extracts. Rats were pretreated with different concentrations of the extract for 7 days. The model of myocardial ischemic-reperfusion injury was established by ligating the left anterior descending (LAD) artery in the heart. Following reperfusion for 40 minutes, the enzyme activity of creatine kinase (CK), lactic acid dehydrogenase (LDH), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px), and the concentration of malondialdehyde (MDA) in the rat serum were measured. The ultrastructural pathological change was observed under transmission electron microscopy (TEM). The serum levels of CK, LDH, and MDA were reduced, and the activity of SOD and GSH-Px were increased significantly, by chloroform and ethyl acetate extracts (P Less Than 0.01, PP Less Than 0.05). The ultrastructural pathological change in myocardial ischemic-reperfusion injury was alleviated by both extracts. The major components in chloroform extract were 7-hydroxy-flavonone and 2',4'-dihydroxy chalcone. 7-Hydroxy-flavanon naringenine naringetol and 2',4'-dihydroxy chalcone were the major components in ethyl acetate extract. Total flavonoids of Tibetan herb O. falcata might alleviate myocardial ischemic-reperfusion injury.

Toxoplasma gondii: Effects of diphenyl diselenide in experimental toxoplasmosis on biomarkers of cardiac function

This study aimed to investigate the effects of diphenyl diselenide (PhSe)2 to treat mice experimentally infected by Toxoplasma gondii on seric biomarkers of cardiac function (creatine kinase, creatine kinase MB, troponin, and myoglobin), and lactate dehydrogenase, as well as to evaluate the enzymatic activity of creatine kinase (CK) and adenylate kinase (AK) in heart tissue. For the study, 40 female mice were divided into four groups of 10 animals each: the group A (uninfected and untreated), the group B (uninfected and treated), the group C (infected and untreated) and the group D (infected and treated). The inoculation was performed with 50 cysts of T. gondii (ME-49 strain). Mice from groups B and D were treated at days 1 and 20 post-infection (PI) with 5 μmol kg−1 of (PhSe)2 subcutaneously. On day 30 PI, the mice were anesthetized and euthanized for blood and heart collection. As a result, it was observed a decrease in AK activity (P < 0.01) in the heart samples of groups C and D compared to the group A. Cardiac CK increased in the group C compared to the group A (P < 0.01). CK levels increased in infected mice (the group C) compared to other groups (A and D). Regarding CK-MB level, there was a decrease in the group D compared to the group B, without statistical difference compared to control groups (A and C). It was observed an increase on myoglobin in groups C and D, differently of troponin, which did not show statistical difference (P < 0.05) between groups. Mice from the group C showed an increase in lactate dehydrogenase (LDH) levels compared to other groups (A, B, and D). Histopathological evaluation of heart samples revealed necrosis, hemorrhagic regions and inflammatory infiltrates in mice from the Group C, differently from the group D where animals showed only inflammatory infiltrates. Based on these results we conclude that the (PhSe)2 had a protective effect on the heart in experimental toxoplasmosis by modulating tissue and seric CK activity, and avoiding an increase on seric LDH levels, probably due to the antioxidant effect of this compound.

Association of heat shock protein 70 gene polymorphisms with acute thermal tolerance, growth, and egg production traits of native chickens in Taiwan

Abstract. Heat stress is among the most challenging environmental conditions affecting commercial poultry. It severely affects growth and egg production, particularly in tropical and subtropical regions. This study aimed to examine physiological responses – including triiodothyronine (T3) levels, enzymatic activity of creatine kinase (CK) and lactate dehydrogenase (LDH), respiratory rates, and cloacal temperature – to acute heat stress associated with different genotypes of the HSP70 gene and to evaluate the association of these polymorphisms with growth and egg production. Genotyping was performed by single-strand conformation polymorphism analysis. The polymorphisms identified were A258A, A258G, and G258G. Twenty 12-week old birds were randomly selected from each genotype and exposed to 40 °C ambient temperature for 1 h. Blood samples were collected at 0 and 1 h following heat stress. Respiratory rate and cloacal temperature were measured following 0, 30, and 60 min of exposure. After 1 h, the A258A genotype exhibited lower levels of CK activity and plasma T3. Neither respiratory rate nor cloacal temperature displayed a significant association with the genotypes. Body weight gain differed among the genotypes for males (F = 3.268, P = 0.041) and females (F = 14.029, P &lt; 0.001), and the A258A genotype exhibited the greatest weight gain at 0–16 weeks of age for both genders. There were no significant differences among genotypes regarding egg weight at first egg or the number of eggs laid until 40 weeks of age. The A258A genotype displayed higher heat tolerance with no negative effects on growth performance and egg production.

Biomarker evaluation of skeletal muscle toxicity following clofibrate administration in rats

The use of sensitive biomarkers to monitor skeletal muscle toxicity in preclinical toxicity studies is important for the risk assessment in humans during the development of a novel compound. Skeletal muscle toxicity in Sprague Dawley Rats was induced with clofibrate at different dose levels for 7 days to compare standard clinical pathology assays with novel skeletal muscle and cardiac muscle biomarkers, gene expression and histopathological changes. The standard clinical pathology assays aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatine kinase (CK) enzyme activity were compared to novel biomarkers fatty acid binding protein 3 (Fabp3), myosin light chain 3 (Myl3), muscular isoform of CK immunoreactivity (three isoforms CKBB, CKMM, CKMB), parvalbumin (Prv), skeletal troponin I (sTnI), cardiac troponin T (cTnT), cardiac troponin I (cTnI), CKMM, and myoglobin (Myo). The biomarker elevations were correlated to histopathological findings detected in several muscles and gene expression changes. Clofibrate predominantly induced skeletal muscle toxicity of type I fibers of low magnitude. Useful biomarkers for skeletal muscle toxicity were AST, Fabp3, Myl3, (CKMB) and sTnI. Measurements of CK enzyme activity by a standard clinical assay were not useful for monitoring clofibrate-induced skeletal muscle toxicity in the rat at the doses used in this study.

The Influence of Alternative Energy Transfer Systems on Respiration in Creatine-Deficient Mouse Cardiomyocytes

Both GAMT-/- and AGAT-/- mice lack a functional creatine kinase (CK) phosphotransfer system due to their deficiency of the enzymes guanidinoacetate methyltranferase (GAMT) and L-arginine:glycine amidinotransferase (AGAT) that synthesize creatine, respectively. As we have shown earlier, GAMT-deficiency is not associated with any changes in cardiomyocyte mitochondrial organization and both GAMT and AGAT-deficiencies do not alter intracellular compartmentation in relaxed cardiomyocytes. The aim of this study was to examine whether alternative energy transfer systems are up-regulated in GAMT-/- and AGAT-/- cardiomyocytes to compensate for the lack of CK phosphotransfer. The experiments were performed on freshly isolated permeabilized adult cardiomyocytes. ATP-stimulated respiration and the influence of activating adenylate kinase (AK) with AMP and hexokinase (HK) with glucose were measured and compared to the influence of activating CK with creatine. Their coupling was assessed using the competitive ADP-trapping PEP/PK assay. The respiration data were complemented with spectrophotometric recordings of total enzyme activities of CK, AK and HK using coupled enzyme assays. As expected on the basis of CK activity distribution between mitochondria and cytosol, the competitive PEP/PK consumed 70-80% of the ADP produced by CK before it reached the mitochondria in both GAMT-/- and AGAT-/- mice. In comparison, PEP/PK consumed 80-85% of the ADP produced by hexokinase and almost all ADP produced by AK in both mouse models. Our results confirm the coupling of CK to respiration in both GAMT-/- and AGAT-/- and their respective wildtype littermates. The coupling of HK is close to that of CK, consistent with some of HK binding to the mitochondria. In contrast, AK seems to be mainly cytosolic. Our results suggest no compensatory changes in the compartmentation of HK, AK or CK in GAMT-/- and AGAT-/- mice.