Serum Creatine Kinase Activity Research Articles

The comparative toxicity of Isocoma species in calves.

Isocoma pluriflora and Isocoma acradenia are toxic plants that contain the putative toxin tremetone. It is common for I. pluriflora to poison livestock in the southwestern United States. I. acradenia has been suspected of poisoning livestock but its toxicity has not been confirmed by association with clinical poisonings or experimental studies. Jersey calves dosed with I. pluriflora and I. acradenia for nine days developed “trembles” characterized by skeletal muscle degeneration and necrosis and large increases in serum creatine kinase activity. This is the first report of I. acradenia toxicity in an animal model. This study also demonstrates that I. pluriflora remains toxic even though tremetone concentrations in the plant were low due to storage of the plant for over five years. Thus, supporting recent research which indicates that another toxin in the plant may be responsible for, or at least contributes to causing “trembles” in livestock.

Diagnosis and treatment of foreign bodies swallowing syndrome in camels (Camelus dromedarius) with special reference to the role of mineral deficiency.

This study describes the clinical presentation of ruminal and reticular foreign body syndrome (RRFBS), and evaluates the effect of mineral deficiency on its occurrence in dromedary camels. Thirty dromedary camels were divided into two groups. Group 1 (control) included 10 apparently healthy she-camels. Group 2 consisted of twenty dromedary camels diagnosed with RRFBS on the basis of clinical, ultrasonographic, hematological, and biochemical examinations. Clinical findings showed decreased appetite and milk yield, tympany, and gradual body weight loss. Ultrasonographic examinations revealed the presence of hyperechoic material with variable degrees of shadowing. Hematological evaluation showed a significant (P<0.05) decrease of the total erythrocyte and lymphocyte count and a significant increase of neutrophils in the camels with RRFBS compared to the controls. Biochemical tests showed a significant elevation in the activity of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), creatine kinase (CK), glucose, creatinine, and blood urea nitrogen and a significant decrease of sodium, chloride, potassium, cobalt, iron, and selenium in the camels with RRFBS compared to the controls. Rumenotomy was performed on the 20 camels as a surgical intervention for treating the RRFBS. By the 6th month postoperatively, all surgically treated camels had completely recovered except for one with tympany and slight swelling in situ. In conclusion, trace element deficiency might play an important role in the occurrence of foreign body ingestion syndrome in dromedary camels. Moreover, clinical, ultrasonographic, hematological, and biochemical examinations are considered as tools assisting in the accurate diagnosis, prognosis, and treatment stratagem for RRFBS in camels.

Supplementation of L-Arginine, L-Glutamine, Vitamin C, Vitamin E, Folic Acid, and Green Tea Extract Enhances Serum Nitric Oxide Content and Antifatigue Activity in Mice.

It has been reported that abundant nitric oxide content in endothelial cells can increase exercise performance. The purpose of this study was to evaluate the potential beneficial effects of a combined extract comprising L-arginine, L-glutamine, vitamin C, vitamin E, folic acid, and green tea extract (LVFG) on nitric oxide content to decrease exercise fatigue. Male ICR (Institute of Cancer Research) mice were randomly divided into 4 groups and orally administered LVFG for 4 weeks. The 4-week LVFG supplementation significantly increased serum nitric oxide content in the LVFG-1X and LVFG-2X groups. Antifatigue activity and exercise performance were evaluated using forelimb grip strength, exhaustive swimming test, and levels of serum lactate, ammonia, glucose, and creatine kinase (CK) after an acute swimming exercise. LVFG supplementation dose-dependently improved exercise performance and nitric oxide content, and it dose-dependently decreased serum ammonia and CK activity after exhaustive swimming test. LVFG's antifatigue properties appear to manifest by preserving energy storage (as blood glucose) and increasing nitric oxide content. Taken together, our results show that LVFG could have the potential for alleviating physical fatigue due to its pharmacological effect of increasing serum nitric oxide content.

Dietary supplementation of guanidinoacetic acid improves growth, biochemical parameters, antioxidant capacity and cytokine responses in Nile tilapia (Oreochromis niloticus)

A total of 180 unsexed Nile Tilapia fish (initial weight, 21 g) fed isonitrogenous (32%), isocaloric (3000 kcal/kg) diets containing different levels of guanidinoacetic acid (GAA) at levels of (GAA1, 0.06%, GAA2, 0.12%, GAA3, 0.18%); for 60 days. Results showed higher final body weight (FBW) and body weight gain (BWG) in groups supplemented with different levels of GAA. Specific growth rate (SGR) was the highest in groups supplemented with 0.12% and 0.18% GAA. Lipid % of whole-body composition was higher in all groups excluding GAA3 group. Serum creatine kinase (CK) activity, cholesterol, and creatinine levels showed a marked significant (P < 0.05) increase in all GAA supplemented groups compared to the control one. Triglycerides level demonstrated a higher elevation (P < 0.05) in both GAA2 and GAA3 supplemented groups. No significant observed in total protein, albumin, globulin, and A/G ratio. Lipid peroxidation marker (malondialdehyde/MDA) is markedly decreased along with a significant increase of superoxide dismutase (SOD), reduced glutathione (GSH), and nitric oxide (NO) levels in both GAA2 and GAA3 compared to other groups. Similarly, interleukin 1β (IL-1β) and tumor necrosis factor (TNF-α) gene expression levels were downregulated along with upregulation of transforming growth factor β1 (TGF-β1) at higher GAA levels, particularly at 0.18%. Our findings give important insights for the growth promoting, antioxidant and immunomodulatory effects of GAA supplemented diet particularly at level of 0.18%.

Creatine-kinase reference intervals at rest and after maximal exercise in Standardbred racehorses

Due to the high variability of data drawn from the literature, aim of the study was to evaluate the effects of exercise on creatine-kinase (CK) serum activity and to determine CK reference intervals (RIs) at rest and post-exercise in healthy Standardbred racehorses. Data concerning history, physical examination, laboratory evaluation and ECG were collected retrospectively from a population of 258 Standardbred racehorses in training that underwent an incremental-maximal treadmill exercise. Those subjects with alterations potentially influencing CK serum activity were excluded. Finally, a reference sample of 194 horses was selected. Blood samples were collected 1 hour before exercise and 6 hour post-exercise and analysed with a spectrophotometric method. Values were compared by Wilcoxon test for paired samples. The effect of age and sex was evaluated by Kruskal-Wallis and Dunn post-test. Statistical significance was set atP&lt;0.05. RIs were determined following Clinical and Laboratory Standard Institute guidelines (CLSI), approved by the American Society for Veterinary Clinical Pathology. Using a macroinstruction set for Microsoft Excel (RefValAdv), RIs were determined with a non-parametric method. A significant increase (P&lt;0.0001) in CK activity post-exercise was observed. Partition by sex and age did not show any statistical difference, either at rest or post-exercise. In RIs determination no outliers were identified. RIs ranged from 25 to 394 U/l at rest and from 44 to 735 U/l post-exercise. To our knowledge, this is the first study considering CK post-exercise RIs in racehorses using CLSI’s guidelines and specific CK-related exclusion criteria. These RIs could be useful to discriminate between physiological and pathological CK post-exercise increase.

McArdle Disease: New Insights into Its Underlying Molecular Mechanisms.

McArdle disease, also known as glycogen storage disease type V (GSDV), is characterized by exercise intolerance, the second wind phenomenon, and high serum creatine kinase activity. Here, we recapitulate PYGM mutations in the population responsible for this disease. Traditionally, McArdle disease has been considered a metabolic myopathy caused by the lack of expression of the muscle isoform of the glycogen phosphorylase (PYGM). However, recent findings challenge this view, since it has been shown that PYGM is present in other tissues than the skeletal muscle. We review the latest studies about the molecular mechanism involved in glycogen phosphorylase activity regulation. Further, we summarize the expression and functional significance of PYGM in other tissues than skeletal muscle both in health and McArdle disease. Furthermore, we examine the different animal models that have served as the knowledge base for better understanding of McArdle disease. Finally, we give an overview of the latest state-of-the-art clinical trials currently being carried out and present an updated view of the current therapies.

Resistance exercise on two consecutive days induces cortisol, CK, IgA responses in active young males

BackgroundReduction in recovery time may prevent physiological variables from returning to pre exercise levels; therefore, it is likely that the athletes will have a decrease in immune response and experience increased stress. The purpose of the current study was to examine whether two consecutive or non-consecutive days of circuit resistance exercise (CRE) on cortisol, creatine kinase (CK) and immunoglobulin A (IgA) responses in active young men. MethodsTen healthy male university students (22.25±1.61 years) performed two consecutive days of circuit resistance exercise (TCD-CRE) and two non-consecutive days of circuit resistance exercise (TNCD-CRE). Participants performed CRE at 75% of their one-repetition maximum (1RM). Blood and saliva samples were taken during baseline and immediately after exercise and analyzed for serum CK activity and salivary concentrations of cortisol and IgA. ResultsBased on the results, there were significant increases in cortisol and CK at post as compared with pre in the TCD-CRE group (P˂0.001, P=0.001). Also, a significant increase in cortisol at post as compared with pre in the TNCD-CRE group was observed (P˂0.001). Additionally, the level of IgA was significantly reduced post exercise when compared to pre value in the TCD-CRE group (P=0.011). On the contrary, there were no significant changes in concentrations of IgA and CK activity in the TNCD-CRE group (P=0.11, P=0.24). Moreover, there were statistically significant differences in cortisol and CK between the groups (P=0.001, P=0.002). ConclusionBased on these data, TCD-CRE causes more immunological responses, and thus may lead to trauma. It seems that there is a need for a 48-h recovery between exercise sessions to prevent the decrease in immune function by CRE.

Consumption of An Anthocyanin-Rich Antioxidant Juice Accelerates Recovery of Running Economy and Indirect Markers of Exercise-Induced Muscle Damage Following Downhill Running.

This study examined the effects of anthocyanin-rich antioxidant juice (AJ) on the recovery of exercise-induced muscle damage (EIMD) and the running economy (RE) following downhill running (DHR). Thirty healthy young men were randomly divided into two blinded groups and consumed either AJ or placebo (PLA) for nine days (240 mL twice-a-day). On day 5, the participants from both groups ran downhill (−15%) for 30 min at 70% of their maximal oxygen uptake (VO2max) speeds. The changes in RE (oxygen uptake (VO2) and perceived effort (PE) during 5-min runs at 80%VO2max) and EIMD (isometric peak torque (IPT), muscle soreness (SOR) and serum creatine kinase activity (CK)) were compared over time and between the groups on the 4 days following DHR. VO2 and PE increased (p < 0.05) immediately following DHR for both groups and remained elevated for PLA until 48h post-DHR while fully recovering 24 h post-DHR for AJ. SOR was greater (p < 0.05) for PLA throughout the study. CK increased for both groups and was greater (p < 0.05) for PLA at 96 h post-DHR. IPT decreased for both groups but recovered faster for AJ (72 h) compared to PLA (no full recovery). AJ accelerated recovery of RE and EIMD and should be used in specific contexts, but not chronically.

Luteolin Attenuates Dexamethasone-Induced Skeletal Muscle Atrophy in Male Albino Rats

AbstractBackground: Glucocorticoid-induced skeletal muscle atrophy is the most common type of drug-induced myopathy.Aim of Study: This study was designated to investigate the effect of luteolin (Lut) on dexamethasone (Dex)-induced skeletal muscle atrophy in rats and the possible mechanisms of this effect.Material and Methods: Forty male Wistar rats divided into; control group, Dex group, and 3 other groups that were treated by Lut 25mg, 50mg and 100mg/kg/day; respectively for 14 days concomitantly with Dex. Body mass and muscle strength were recorded. Serum creatine kinase (CK) activity was assessed. Gastrocnemius muscle was weighed and proc-essed for assay of tissue reduced glutathione (GSH), malond-ialdehyde (MDA) levels. Histopathological and immunohis-tochemical studies were carried out.Results: Lut dose-dependently increased GSH, and cross-sectional area (CSA), and decreased MDA and caspases-3 immunoreactivity. Lut in a dose 50mg/kg/day improved the muscle mass and strength.Conclusion: This study demonstrates that luteolin is a protective agent against glucocorticoid-induced atrophy through antioxidant and anti-apoptotic properties.

SIRT1 deficiency interferes with membrane resealing after cell membrane injury.

Activation of SIRT1, an NAD+-dependent protein deacetylase, ameliorates muscular pathophysiology of δ-sarcoglycan-deficient TO-2 hamsters and dystrophin-deficient mdx mice. We found that SIRT1 was highly expressed beneath the cellular membranes of muscle cells. To elucidate functional roles of SIRT1 on muscles, skeletal muscle-specific SIRT1 knockout mice (SIRT1-MKO) were generated. SIRT1-MKO mice showed muscular pathology similar to mild muscular dystrophies with increased numbers of centrally nucleated small myofibers and decreased numbers of middle-sized (2000–3001 μm2) myofibers compared to those of wild-type (WT) mice. Accordingly, SIRT1-MKO mice showed significantly decreased exercise capacity in treadmill and inverted hanging tests with higher levels of serum creatine kinase activities compared with those in WT mice. Evans blue dye uptake after exercise was greater in the muscles of SIRT1-MKO than those of WT mice, suggesting membrane fragility in SIRT1-MKO mice. Because SIRT1 was dominantly localized beneath the membranes of muscular cells, SIRT1 may have a new role in the membranes. We found that levels of fluorescent FM1-43 dye intake after laser-induced membrane disruption in C2C12 cells were significantly increased by SIRT1 inhibitors or Sirt1-siRNA compared with those of control cells. Inhibition of SIRT1 or SIRT1-knockdown severely disturbed the dynamic aggregation of membrane vesicles under the injured site but did not affect expression levels of membrane repair proteins. These data suggested that SIRT1 had a critical role in the resealing of membrane-ruptured muscle cells, which could affect phenotypes of SIRT1-MKO mice. To our knowledge, this report is the first to demonstrate that SIRT1 affected plasma-membrane repair mechanisms.

Effects of Selenium Supplementation in Obese Selenocysteine Lyase Knockout Mouse (P24-022-19)

ObjectivesWe previously demonstrated that disruption of selenocysteine lyase (Scly) in mice leads to the development of obesity and metabolic syndrome under selenium deficiency, with effects on glucose homeostasis in the liver. It is unknown whether the physiology of skeletal muscle, a key tissue in glucose disposal, is also affected by the disruption of Scly. Here, we investigated the effects of a high-fat diet supplemented with selenium in the muscle physiology of Scly knockout (KO) mice MethodsAge-matched homozygous male and female Scly KO and wild type (WT) from C57BL/6 J background were group-caged and fed for three months to a diet containing 45% kcal fat and 0.25 ppm (adequate) or 1 ppm (high) of selenium as sodium selenite. Serum, liver, soleus, and brown adipose tissue (BAT) were collected and assessed for total glutathione peroxidase (GPX) activity and creatine kinase (CK). Total RNA was extracted from soleus and liver, reverse-transcribed, and used in qPCR. ResultsFollowing an adequate selenium intake, total GPX activity in serum, mRNA of GPX1 and selenoprotein P in the liver, and mRNA of selenoprotein N in soleus were unchanged of Scly KO compared to WT mice, both in males and females. We observed five-fold increase of CK activity in serum and a one-fold decrease in soleus of Scly KO male mice when compared with WT. Increased CK levels in serum have been related with muscle impairment. Interestingly, when male Scly KO mice were fed a high selenium diet, we observed the opposite effect, with serum CK activity significantly decreased, while in soleus CK activity increased in Scly KO mice. CK activity levels on liver or BAT were unchanged. CK activity in serum was unchanged in female mice, corroborating to the previously described sexual dimorphism for these animals. These results suggest an improvement in Scly KO muscle health after selenium supplementation. ConclusionsAdequate selenium levels maintain selenium homeostasis and ensure the maintenance of selenoprotein levels, but high selenium intake may be necessary to preserve muscle health. Funding SourcesFAPESP/Brazil, NIDDK-NIH/USA, NIMHD-NIH/USA.

Rhabdomyolysis: a 10-year retrospective study of patients treated in a medical department.

Rhabdomyolysis is a common and potentially life-threatening syndrome, and acute kidney injury (AKI) is a serious complication. We performed a 10-year retrospective study that included all patients treated for rhabdomyolysis in a medical clinic. We examined the relationships between the levels of creatine kinase (CK), myoglobin, and creatinine (as a marker of renal function and thereby AKI), and whether the myoglobin/CK ratio could be a valuable tool in the clinical evaluation of this patient group. Clinical characteristics were noted. The study included all patients treated for rhabdomyolysis in the Department of Medicine, Oslo University Hospital Ulleval, from 2003 to 2012. Rhabdomyolysis was defined as a serum CK activity more than five times the upper reference limit. A total of 341 patients were included in the study; 51% developed AKI, and 20% of those required dialysis. Logistic regression showed that myoglobin concentration [P < 0.001, odds ratio (OR) = 6.24] was a better predictor than CK activity (P = 0.001, OR = 3.45) of the development of AKI. The myoglobin/CK ratio was a good predictor of AKI (P < 0.001, OR = 5.97). The risk of developing AKI increased with increasing myoglobin/CK ratio (P < 0.001); a ratio more than 0.2 was associated with an increased likelihood of developing AKI. Serum myoglobin concentration was a better predictor of AKI than was serum CK activity. The myoglobin/CK ratio may be useful for assessing the likelihood of developing AKI.

Strength Loss After Eccentric Exercise Is Related to Oxidative Stress but Not Muscle Damage Biomarkers

ABSTRACTPurpose: The purpose of this study was to investigate (a) time-dependent changes in muscle damage (MD) biomarkers, oxidative stress (OS) indices, and maximum strength performance; (b) the relationship between changes in maximum strength performance and changes in MD and OS indices; and (c) whether eccentric exercise-induced MD is related to OS. Method: Twenty-nine male volunteers (age: 22.13 ± 3.1 years) participated in the study. Participants performed 60 maximal eccentric actions of the elbow flexors at a constant velocity of 60°·s−1. Maximum isokinetic strength (MIS), visual analog scale soreness scores, serum creatine kinase (CK) activity, total antioxidant status, total oxidant status (TOS), protein carbonyl (PCO), and 8-hydroxydeoxyguanosine level were analyzed. Blood samples were obtained before, immediately after, and 24 h, 48 h, and 96 h after the eccentric exercise. Change in total work (%ΔTWk), peak torque (%ΔPT), and OS index were calculated. Results: CK, PCO, and TOS significantly increased over time (p < .05). However, no significant main effect was observed for MIS or any other investigated biomarkers (p > .05). MIS was not related to MD or OS indices. However, %ΔTWk demonstrated a moderate inverse correlation with OS indices. No significant relationship was observed between %ΔPT and any of the selected biomarkers. Conclusions: Our findings confirm the hypothesis that acute eccentric exercise increases MD biomarkers and OS indices. However, indices of OS damage were significantly related, particularly, to the strength loss of flexors. This finding suggests that the decline in strength performance is not the primary determinant of the magnitude of MD following voluntary eccentric contraction.

Ca2+/Calmodulin-Dependent Protein Kinase II Regulation by Inhibitor 1 of Protein Phosphatase 1 Protects Against Myocardial Ischemia-Reperfusion Injury.

Ca2+/calmodulin-dependent protein kinase IIδ (CaMKIIδ) plays a vital role in cardiovascular system. However, the potential protective role of inhibitor 1 of protein phosphatase 1 (I1PP1), which can regulate CaMKII, on myocardial ischemia-reperfusion (I/R) injury remains unknown. In the present study, expression of CaMKIIδ variants was detected by quantitative real-time polymerase chain reaction. I1PP1 was overexpressed by pericardial injection of recombinant adenovirus. Two weeks later, rats were subjected to left anterior descending ligation for 30 minutes followed by reperfusion. Myocardial infarct size was assessed by Evans blue/triphenyl tetrazolium chloride staining. Serum creatine kinase (CK) and lactate dehydrogenase (LDH) activity as well as myocardial pathological structure were detected. CaMKII activity was evaluated by phosphorylation of phospholamban (PLB) and oxidation of CaMKII. Expression of dynamin-related protein 1 (DRP1) and optic atrophy 1 (OPA1) in the mitochondria was measured by Western blot. We found that CaMKIIδA and CaMKIIδB expression decreased, while the expression of CaMKIIδC increased after myocardial I/R. Moreover, after 30-minute ischemia followed by 6 hours of reperfusion, I1PP1 overexpression reduced myocardial infarct size, decreased serum CK and LDH activity, ameliorated myocardial pathological structure, inhibited PLB phosphorylation at Thr17, suppressed CaMKII oxidation, elevated CaMKIIδA and CaMKIIδB variants but reduced CaMKIIδC variants, attenuated myocardial oxidative stress, improved myocardial mitochondrial ultrastructure, increased mitochondrial number and mitochondrial DNA copy number, and decreased DRP1 but increased OPA1 protein expression from the mitochondria in rats. Thus, I1PP1 regulated CaMKII, protected mitochondrial function, reduced oxidative stress, and attenuated myocardial I/R injury.

Protective effect of alpha-lipoic acid against apical periodontitis-induced cardiac injury in rats.

This study was designed to assess the possible protective effect of alpha-lipoic acid (ALA) on apical periodontitis (AP)-induced cardiac injury. Wistar albino rats were randomized into four groups: control; ALA; AP; and ALA+AP. Rats of the control and ALA groups were not endodontically treated, but saline and ALA (100mgkg-1 ) were administered. In rats of the AP and ALA+AP groups, the pulp chambers of mandibular first molar teeth were exposed and left open for 30d to induce AP. Saline and ALA (100mgkg-1 ) were administered intraperitoneally every 24h during the experiment. At the end of the experiment, the rats were killed. Establishment of AP was verified by radiographic and histopathological evaluation. Serum alkaline phosphatase (ALP), lactate dehydrogenase (LDH), creatine kinase (CK), and superoxide dismutase (SOD) activities were determined using an automated biochemical analyzer, and the structural cardiac injury was assessed pathologically. Serum ALP, LDH, and CK activities were elevated, and SOD activities were decreased, in the AP group. The changed enzyme activities were significantly normalized by treatment with ALA. We conclude that ALA administration alleviated the AP-induced heart injury and improved cardiac structure and function, and therefore this agent may be of potential therapeutic value in protecting cardiac tissue from systemic injury caused by AP.

SAT-089 Statin Use Associated with Symptomatic and Asymptomatic Hyperckemia: A Retrospective Cohort Study

Objective Statins are the most commonly used cholesterol-lowering drugs to reduce cardiovascular risks. Elevation of serum creatine kinase (CK) activity with or without myopathy constitutes the most common forms of statin intolerance. We aimed to examine the frequency of statin-associated symptomatic and asymptomatic myopathy among consecutive patients with hyperCKemia. Methods We performed a retrospective review of electronic and paper medical records and selected 1,278 consecutive patients with hyperCKemia who were treated from 2013 to 2016 at the (undisclosed). We evaluated potential causes of hyperCKemia and analyzed specifically records of statin users by collecting demographic data, medical history, neuromuscular examination and biochemical profiles. Results In all, 290 (22.7%) patients with hyperCKemia were statin users, and among them, 79 (43.9%, or 6.2% of total) were considered to be due to statin exposure after normalization of serum CK activity with statin discontinuation (88.6% were asymptomatic). The mean age was 58.6 years (range 26-95) and 26.6% were women. Only 9 (11.4%) patients had symptomatic hyperCKemia with myopathy syndrome. The mean serum CK activity with statin exposure was 326.3±150 IU/L (normal reference: 30-223 IU/L) and 198.6±82.9 IU/L after statin discontinuation. Atorvastatin (74.7%) was the most commonly used statin, followed by pravastatin (11.4%) and simvastatin (7.6%). In all, 41 (51.9%) patients had type 2 diabetes mellitus (T2D), 55 (69.6%) had chronic kidney disease (CKD), 7 (8.9%) had chronic liver disease, 15 (19%) hypothyroidism and 4 (5.1%) had HIV infection. Conclusion Our study suggests that statins exposure is a common cause of hyperCKemia, but that the great majority of cases are asymptomatic. Further studies are necessary to clarify whether T2D and CKD are independent risk factors for hyperCKemia or epiphenomena to statins indications. Reference Chatzizisis, Y.S., Koskinas, K.C., Misirli, G. et al. Drug-Safety (2010) 33: 171.

The Effects of Ergosta-7,9(11),22-trien-3β-ol from Antrodia camphorata on the Biochemical Profile and Exercise Performance of Mice.

Antrodia camphorata (AC) is a rare and unique mushroom that is difficult to cultivate. Previous studies have demonstrated the bioactivity of the compound Ergosta-7,9(11),22-trien-3β-ol (EK100) from AC in submerged culture. The purpose of this study is to evaluate the potential beneficial effects of EK100 on fatigue and ergogenic functions following physiological challenge. Male ICR (Institute of Cancer Research) mice were randomly divided into three groups (n = 8 per group) and orally administered EK100 for six weeks at 0 (Vehicle), 10 (EK100-1X), and 20 (EK100-2X) mg/kg/day. The six-week Ek100 supplementation significantly increased grip strength (p = 0.0051) in trend analysis. Anti-fatigue activity was evaluated using 15-min. acute exercise testing and measuring the levels of serum lactate, ammonia, glucose, blood urea nitrogen (BUN), and creatine kinase (CK) after a 15-min. swimming exercise. Our results indicate that AC supplementation leads to a dose-dependent decrease in serum lactate, ammonia, BUN, and CK activity after exercise and significantly increases serum glucose and glycogen content in liver tissues. Biochemical and histopathological data demonstrated that long term daily administration of EK100 for over six weeks (subacute toxicity) was safe. EK100’s anti-fatigue properties appear to be through the preservation of energy storage, increasing blood glucose and liver glycogen content, and decreasing the serum levels of lactate, ammonia, BUN, and CK. EK100 could potentially be used to improve exercise physiological adaptation, promote health, and as a potential ergogenic aid in combination with different nutrient strategies.

Antioxidative and Cardioprotective Effects of Schisandra chinensis Bee Pollen Extract on Isoprenaline-Induced Myocardial Infarction in Rats.

Oxidative stress plays an important role in the pathogenesis of myocardial infarction (MI). Schisandra chinensis bee pollen extract (SCBPE) possesses powerful antioxidant capacity. This study aimed to further explore the antioxidative and cardioprotective effects of SCBPE on acute MI induced by isoprenaline (ISO) in rats. The rats were intragastrically administrated with SCBPE (600, 1200, or 1800 mg/kg/day) and Compound Danshen dropping pills (270 mg/kg/day) for 30 days, then subcutaneously injected with ISO (65 mg/kg/day) on the 29th and 30th day. Compared with the model group, pretreatment with middle and high doses of SCBPE significantly reduced serum aspartate transaminase, lactate dehydrogenase, and creatine kinase activities and increased myocardial superoxide dismutase, glutathione peroxidase, and catalase activities. The histopathologic aspects showed that pathological heart change was found in the model group and reduced to varying degrees in the SCBPE groups. Moreover, the protein expression of nuclear factor-erythroid 2-related factor 2 (Nrf-2), heme oxygenase-1 (HO-1), and Bcl2 in the heart increased in the SCBPE groups, while that of Bax decreased compared to the model group. Besides this, uridine was isolated from S. chinensis bee pollen for the first time. This study could provide a scientific basis for using Schisandra chinensis bee pollen as a functional food for the prevention of MI.

Effects of heat challenge on growth performance, ruminal, blood and physiological parameters of Chinese crossbred goats

The aim of this study was to evaluate the effects of heat challenge on growth performance as well as ruminal, blood and physiological parameters of Chinese crossbred goats. During the heat challenge period, the goats exhibited significantly higher skin temperatures, pulse rates and respiration rates than during the control period. The rumen pH and concentrations of ammonia-N (NH3-N), total volatile fatty acids (TVFAs), acetic acid and propionic acid were significantly lower during the heat challenge period than during the control period. In addition, the butyric acid concentration, acetate-to-propionate ratio (A/P ratio) and oxidation–reduction potential (ORP) in the rumen were significantly increased in heat-challenged goats compared to those in control period. During the heat challenge period, the goats showed significantly higher serum creatine kinase (CK) activity and blood urea nitrogen (BUN) and malonaldehyde (MDA) concentrations than during the control period, while the glutathione peroxidase (GSH-Px) activity and the serum total protein (TP) and vitamins C and E concentrations were significantly lower (P < 0.05) during the control period. During the heat challenge period, the goats exhibited significantly lower (P < 0.05) dry matter (DM) intake (DMI) and average daily gain (ADG) than during the control period and significantly higher (P < 0.05) digestibilities of DM, neutral detergent fiber (NDF) and acid detergent fiber (ADF) than during the control period. These results suggest that the effect of a heat challenge on goats is systemic. Therefore, in goat production practices, the adverse effects of heat stress should not be ignored.

Relation of reproductive disturbance in sheep and Leptospira interrogans serovar Icterohaemorrhagiae infection: Impacts on cellular oxidation status

This study evaluated the seropositivity of Brucella abortus and Leptospira interrogans in ewes with reproductive disturbances in southern Brazil and verified the creatine kinase (CK) activity and oxidation status via assessment of superoxide dismutase, glutathione peroxidase and glutathione transferase in serum of seropositive animals for L. interrogans serovar Icterohaemorrhagiae. For Leptospira infection 381 animals with clinical history of reproductive disturbance from Planalto Serrano de Santa Catarina (Brazil) were analyzed, showing an occurrence for L. interrogans of 20.2% from which 81.8% were seropositive for L. interrogans Icterohaemorrhagiae. Serovars Wolfii, Grippothyphosa, Bratislava, Canicola and Butembo were also identified. In the case of B. abortus, positive cases were identified by buffered acidified antigen, finding 14 positive samples, but none of them were positive after a second test (2-mercaptoethanol), showing the absence of relationship between infection with B. abortus and abortion in the tested individuals. Serum reactive oxygen species (ROS) levels and CK activity were found higher in animals positive for Leptospira infection, presenting higher titrations (1:320) than non-infected individuals. Serum glutathione peroxidase activity was higher in positive animals with titrations 1:160 and 1:320, while serum glutathione S-transferase was higher in positive individuals only for titrations 1:320. Serum superoxide dismutase showed lower activity in infected animals with titrations of 1:320. Our results show the region of Planalto Serrano de Santa Catarina with a high occurrence levels of sheep infected by L. interrogans serovar Icterohaemorrhagiae, from which animals with high titrations (1:320) present oxidative stress elicited by excessive ROS production, triggering the stimulation of antioxidant systems to counter this excess. In summary, ovine with higher titrations (1:320) present oxidative damage that can contribute to disease pathophysiology.