Diagnostic Accuracy of Lactate Dehydrogenase/Adenosine Deaminase Ratio in Differentiating Tuberculous and Parapneumonic Effusions: A Systematic Review

BACKGROUND

Tuberculous pleural effusion (TPE) and parapneumonic effusion (PPE) are often difficult to differentiate owing to the overlapping clinical features. Observational studies demonstrate that the ratio of lactate dehydrogenase to adenosine deaminase (LDH/ADA) is lower in TPE compared to PPE, but integrated analysis is warranted.

METHODS

We conducted a systematic review to evaluate the diagnostic accuracy of the LDH/ADA ratio in differentiating TPE and PPE. We explored the PubMed and Scopus databases for studies evaluating the LDH/ADA ratio in differentiating TPE and PPE.

RESULTS

From a yield of 110 studies, five were included for systematic review. The cutoff value for the LDH/ADA ratio in TPE ranged from <14.2 to <25. The studies demonstrated high heterogeneity, precluding meta-analysis. Quality Assessment of Diagnostic Accuracy Studies Tool 2 assessment revealed a high risk of bias in terms of patient selection and index test.

CONCLUSION

LDH/ADA ratio is a potentially useful parameter to differentiate between TPE and PPE. Based on the limited data, we recommend an LDH/ADA ratio cutoff value of <15 in differentiating TPE and PPE. However, more rigorous studies are needed to further validate this recommendation.

Salivary protein biomarkers for diagnosis of oral squamous cell carcinoma

OSCC (Oral Squamous Cell Carcinoma) is a major health challenge in many parts of the world. It occurs most commonly in males and is associated with tobacco, pan, or areca nut consumption. One of the major challenges associated with the management of OSCC is late diagnosis. As a result, the treatment required is more aggressive, expensive, and has poor prognostic value. On the other hand, early diagnosis of OSCC can be life-saving with less aggressive treatment and a better prognosis. A diagnostic method for early diagnosis of OSCC is greatly needed. A lot of research efforts have been made to identify biomarkers that can act as tools to classify the tumor status of the patient. Various biological fluids and tissues have been explored for such studies. Saliva appears to be the most attractive biological sample with many potential advantages over other matrices such as blood or tissue. Saliva as a diagnostic fluid has the advantage of ample availability, being non-invasive and being in the vicinity of the tumor, and having a less complex composition. Our paper provides an updated review of the state of the art of research in the area of salivary biomarkers for oral squamous cell carcinoma. The paper gives an account of methods for saliva collection, followed by a brief description of various protein biomarkers discovered to date, along with their status quo.

Serum and Cerebrospinal Fluid Lactate Dehydrogenase in Children with Febrile Convulsions

Objective

Tissue damage caused by febrile convulsion has not still been proved or refuted completely. Given the fact that lactate dehydrogenase as an intracellular enzyme can be increased due to tissue damage, we decided to evaluate serum and cerebrospinal fluid lactate dehydrogenase in children with febrile convulsion.

Materials & Methods

This is a cross-sectional study on 166 children aged 6-24 month, in three groups of simple febrile convulsion (n=56), complex febrile convulsion (n=27) with 3 different subgroups (recurrence in 24 hours, duration >15 minutes, and with focal components), and control (n=83). Patients' serum and cerebrospinal fluid specimens were collected after meeting the inclusion criteria. Demographic information was documented and patients' serum and cerebrospinal fluid lactate dehydrogenase and glucose were measured. Data were analyzed using SPSS software.

Result

The mean serum lactate dehydrogenase in simple febrile convulsion, complex febrile convulsion, and controls were 501.57± 143.70, 553.07±160.22, and 505.87±98.73 U/L, respectively. The mean cerebrospinal fluid lactate dehydrogenase in simple, complex febrile convulsion, and control groups were 22.58±11.92, 29.48±18.18, and 21.56±17.32 U/L, respectively. Only cerebrospinal fluid lactate dehydrogenase difference between complex febrile convulsion and control group (p=0.039) (In the duration >15 minutes subgroup and controls, p=0.028) was statistically significant. There was a significant difference between sex and serum lactate dehydrogenase in thesame subgroup of complex group (p=0.012).

Conclusion

Complex febrile convulsion may lead to increase of lactate dehydrogenase in cns of CNS cellular damage.

Lactate Dehydrogenase and β-Glucuronidase as Salivary Biochemical Markers of Periodontitis Among Smokers and Non-Smokers

Objectives

This study aimed to establish lactate dehydrogenase (LDH) and β-glucuronidase as salivary biomarkers of periodontitis among smokers and non-smokers.

Methods

This cross-sectional case-control study was conducted at the Aligarh Muslim University, Aligarh, India, between January and June 2017. A total of 200 participants were divided into four groups based on their periodontal and smoking statuses. Unstimulated mixed saliva samples were collected to estimate LDH and β-glucuronidase levels. In addition, total protein was estimated using Lowry's method.

Results

There was a significant increase in enzyme activity in the periodontitis groups compared to the non-periodontitis groups (P <0.001). However, significantly lower enzyme activity was observed among smokers, irrespective of periodontal status (P <0.001). Nevertheless, a receiver operating characteristic curve analysis indicated the diagnostic potential of both enzymes to be fair-to-excellent.

Conclusion

Although smoking was found to significantly alter enzyme activity, LDH and β-glucuronidase were reliable salivary biomarkers of periodontitis among both smokers and non-smokers.

Correlations between the Maximum Standard Uptake Value of Positron Emission Tomography/Computed Tomography and Laboratory Parameters before and after Treatment in Patients with Lymphoma

Background:

After the first examination of patients with lymphoma diagnosis, important laboratory tests such as complete blood count; albumin, kidney and liver function tests; uric acid; β2-microglobulin; C-reactive protein (CRP); erythrocyte sedimentation rate (ESR); and lactate dehydrogenase (LDH) examinations are recommended. In this study, our aim was to find the relationship between laboratory parameters and the maximum standard uptake value (SUV_max) of positron emission tomography/computed tomography (PET/CT) in patients with lymphoma at the diagnosis and after treatment.

Methods:

Thirty-four lymphoma patients treated at Mustafa Kemal University Internal Medicine Clinic between 2014 and 2017 were included in this retrospective study. Results of CRP, ESR, LDH, albumin, and white blood cell (WBC) count were recorded before each PET scan test, and each parameter was analyzed for correlation with SUV_max measurements.

Results:

Spearman's correlation test showed that the after-treatment SUV_max values were significantly correlated with the after-treatment LDH, ESR, and CRP values (for LDH, ESR, and CRP, R²: 0.453, 0.426, and 0.351; P = 0.007, 0.012, and 0.042, respectively). On the other hand, albumin and WBC count did not show a significant correlation with the after-treatment SUV_max values (all P > 0.05).

Conclusions:

CRP, ESR, and LDH values may also be good predictors in patients for whom PET/CT imaging cannot be performed.

Patient inflammatory status and CD4+/CD8+ intraepithelial tumor lymphocyte infiltration are predictors of outcomes in high-grade serous ovarian cancer

BACKGROUND

High-grade serous ovarian cancer (HGSOC) is the most prevalent and aggressive histologic type of ovarian cancer. To date, there are no reliable biomarkers to effectively predict patient prognosis. Studies have demonstrated inflammation and tumor infiltrating lymphocytes (TILs) correlate with a bad and good prognosis, respectively. Here, we sought to evaluate systemic inflammation and TILs as early prognostic markers of survival.

METHODS

Neutrophil-to-lymphocyte ratio (NLR) and serum Lactate Dehydrogenase (LDH) were used as indicators of systemic inflammation. NLR, serum LDH, tumor infiltrating lymphocytes (TILs), PDL1 and quality of debulking surgery were evaluated as determinants of progression-free survival (PFS) and overall survival (OS) in a cohort of 128 HGSOC patients.

RESULTS

Initial univariate analysis showed that systemic inflammation measures (NLR and serum LDH), debulking surgery, and intra-epithelial TILs have a significant impact on both PFS and OS. After adjustment for several variables, multivariate analyses confirmed intraepithelial CD4+ T-cells, systemic inflammation measures, PDL1 and debulking surgery as determinants of better OS and PFS.

CONCLUSIONS

Systemic inflammation and TILs are early determinants of OS in HGSOC. Other variables such as the quality of debulking surgery and PDL1 also improve survival of patients. Regarding TIL sub-populations, intraepithelial CD4+ cells are associated to an increase in both PFS and OS. We also confirmed previous reports that demonstrate intraepithelial CD8+ cells correlate with an increase on PFS in ovarian cancer. A combined score using systemic inflammation and TILs may be of prognostic value for HGSOC patients.

A Survival Model in Locally Advanced and Metastatic Pancreatic Ductal Adenocarcinoma

The prognostic role of serum LDH, CA19-9, CRP and ALB in PDAC patients are controversial. In contrast to single factor, there is much less information about the prognostic value of the combination of the four factors in locally advanced and metastatic PDAC patients. It's essential to set up a survival model with the combination of tumor metabolism, tumor biomarker, systemic inflammation and nutritional status to eliminate the prognostic inaccuracy in single biomarker. 94 advanced PDAC patients who received palliative chemotherapy from 2009 to 2017 were recruited for this study. The predictive value of pretreatment serum LDH, CA19-9, CRP and ALB levels for OS were evaluated, and the same as combination of the four factors. It was confirmed that serum LDH, CA19-9, CRP and ALB levels were independent prognostic factors for OS by multivariate analyses. The results of Kaplan-Meier analyses revealed that serum LDH, CA19-9, CRP, ALB levels as well as the combination of the four factors were correlated with OS. It's concluded that the combination of the pretreatment serum LDH, CA19-9, CRP and ALB levels is a prognostic factor for advanced PDAC patients.

Effects of Methylsulfonylmethane (MSM) on exercise-induced oxidative stress, muscle damage, and pain following a half-marathon: a double-blind, randomized, placebo-controlled trial

Background

Oxidative stress and muscle damage occur during exhaustive bouts of exercise, and many runners report pain and soreness as major influences on changes or breaks in training regimens, creating a barrier to training persistence. Methylsulfonylmethane (MSM) is a sulfur-based nutritional supplement that is purported to have pain and inflammation-reducing effects. To investigate the effects of MSM in attenuating damage associated with physical exertion, this randomized, double-blind, placebo-controlled study evaluated the effects of MSM supplementation on exercise-induced pain, oxidative stress and muscle damage.

Methods

Twenty-two healthy females (n = 17) and males (n = 5) (age 33.7 ± 6.9 yrs.) were recruited from the 2014 Portland Half-Marathon registrant pool. Participants were randomized to take either MSM (OptiMSM®) (n = 11), or a placebo (n = 11) at 3 g/day for 21 days prior to the race and for two days after (23 total). Participants provided blood samples for measurement of markers of oxidative stress, and completed VAS surveys for pain approximately one month prior to the race (T₀), and at 15 min (T₁), 90 min (T₂), 1 Day (T₃), and 2 days (T₄) after race finish. The primary outcome measure 8-hydroxy-2-deoxyguanine (8-OHdG) measured oxidative stress. Secondary outcomes included malondialdehyde (MDA) for oxidative stress, creatine kinase (CK) and lactate dehydrogenase (LDH) as measures of muscle damage, and muscle (MP) and joint pain (JP) recorded using a 100 mm Visual Analogue Scale (VAS). Data were analyzed using repeated and multivariate ANOVAs, and simple contrasts compared post-race time points to baseline, presented as mean (SD) or mean change (95% CI) where appropriate.

Results

Running a half-marathon induced significant increases in all outcome measures (p < 0.001). From baseline, 8-OHdG increased significantly at T₁ by 1.53 ng/mL (0.86–2.20 ng/mL CI, p < 0.001) and T₂ by 1.19 ng/mL (0.37–2.01 ng/mL CI, p < 0.01), and fell below baseline levels at T₃ by −0.46 ng/mL (−1.18–0.26 CI, p > 0.05) and T₄ by −0.57 ng/mL (−1.27–0.13 CI, p > 0.05). MDA increased significantly at T₁ by 7.3 μM (3.9–10.7 CI, p < 0.001). Muscle damage markers CK and LDH saw significant increases from baseline at all time-points (p < 0.01). Muscle and joint pain increased significantly from baseline at T₁, T₂, and T₃ (p < 0.01) and returned to baseline levels at T₄. Time-by-treatment results did not reach statistical significance for any outcome measure, however, the MSM group saw clinically significant (Δ > 10 mm) reductions in both muscle and joint pain.

Conclusion

Participation in a half-marathon was associated with increased markers of oxidative stress, muscle damage, and pain. MSM supplementation was not associated with a decrease from pre-training levels of oxidative stress or muscle damage associated with an acute bout of exercise. MSM supplementation attenuated post-exercise muscle and joint pain at clinically, but not statistically significant levels.

Correlation of Patterns of Bone Marrow Infiltration and Biochemical factors in Non-Hodgkin Lymphoma

OBJECTIVES

To investigate the patterns of bone marrow involvement in in Non-Hodgkin's Lymphoma (NHL) patients and to correlate the patterns with β₂ microglobulin (β2m) and lactate dehydrogenase 2 (LD2) levels in these patients.

METHODS

It was a cross sectional study which was conducted in two years at Post Graduate Medical Institute, Lahore and at Centre of Excellence in Molecular Biology (CEMB), Lahore. The study was conducted on 50 subjects irrespective of age and sex divided into two groups i.e. Group-A comprising 20 normal healthy controls while Group-B consisted of 30 patients of NHL with bone marrow infiltration. Bilateral bone marrow trephine biopsy was done to assess the patterns of bone marrow infiltration. Serum β2m and LD2 isoenzyme levels were determined in already diagnosed 30 patients of NHL. The values were compared with 20 healthy age and sex matched controls. Correlation coefficients were determined using Pearson's Correlation Coefficient. The estimations were made prior to the institution of chemotherapy.

RESULTS

β2m and LD2 levels were significantly (p-Value < 0.05) raised in NHL patients with disease advancement and were compared with controls. These serological markers showed negative correlation (-0.235 for β2m and -0.133 for LD2) with the spread of disease and patterns of involvement in NHL patients.

CONCLUSION

By observing the patterns of bone marrow involvement in NHL patients possible guidelines about prognosis and treatment protocols can be obtained as the serological markers levels correlate well with the spread of disease and patterns of involvement in NHL patients.

Sodium Nitroprusside Changed The Metabolism of Mesenchymal Stem Cells to An Anaerobic State while Viability and Proliferation Remained Intact

Objective

We used sodium nitroprusside (SNP), a nitric oxide (NO) releasing molecule, to understand its effect on viability and proliferation of rat bone marrow mesenchymal stem cells (BM-MSCs).

Materials and Methods

This experimental study evaluated the viability and morphology of MSCs in the presence of SNP (100 to 2000 µM) at 1, 5, and 15 hours. We chose the 100, 1000, and 2000 µM concentrations of SNP for one hour exposure for further analyses. Cell proliferation was investigated by the colony forming assay and population doubling number (PDN). Na⁺, K⁺, and Ca²⁺ levels as well as activities of lactate dehydrogenase (LDH), alkaline phosphatase (ALP), aspartate transaminase (AST), and alanine transaminase (ALT) were measured.

Results

The viability of MSCs dose-dependently reduced from 750 µM at one hour and 250 µM at 5 and 15 hours. The 100 µM caused no change in viability, however we observed a reduction in the cytoplasmic area at 5 and 15 hours. This change was not observed at one hour. The one hour treatment with 100 µM of SNP reduced the mean colony numbers but not the diameter when the cells were incubated for 7 and 14 days. In addition, one hour treatment with 100 µM of SNP significantly reduced ALT, AST, and ALP activities whereas the activity of LDH increased when incubated for 24 hours. The same treatment caused an increase in Ca²⁺ and reduction in Na⁺ content. The 1000 and 2000 µM concentrations reduced all the factors except Ca²⁺ and LDH which increased.

Conclusion

The high dose of SNP, even for a short time, was toxic. The low dose was safe with respect to viability and proliferation, especially over a short time. However elevated LDH activity might increase anaerobic metabolism.

Evaluation of Acute Oral Toxicity of Ethanol Leaves Extract of Catharanthus roseus in Wistar Albino Rats

INTRODUCTION

Herbal drugs have gained importance globally in the treatment of various diseases. Catharanthus roseus is traditionally used as an anti diabetic and anti cancer drug. To the best of our knowledge limited data are available on acute and sub acute toxicity of C. roseus extract despite its wide spread use in traditional medicine. The present study was under taken to evaluate the acute oral toxicity of the ethanol leaves extract of C. roseus.

AIM

To investigate the acute oral toxic effects of ethanol leaves extract of C. roseus. The objective of the study was to evaluate organ toxicity related to heart, liver and kidney in wistar albino rats.

MATERIALS AND METHODS

The experiment was done based on the Organization for Economic Co-operation and Development (OECD) guideline 420. The study included twenty five non pregnant female wistar rats (n=25). Sighting study was done using the fixed dose method. The study was conducted by giving a single dose of test drug varying from 5, 50, 300 and 2000 mg and animals were observed for fourteen days. Blood samples were collected and biochemical findings SGPT, SGOT, urea, creatinine, creatinine phosphokinase and Lactate Dehydrogenase (LDH) were analyzed. Food consumption, water intake and histopathology changes were evaluated.

RESULTS

Catharanthus roseus Extract (CRE) at a dose of 2000 mg did not produce mortality. SGOT, SGPT, Creatinine phosphokinase, LDH, urea and creatinine were elevated in 300 mg and 2000 mg doses.

CONCLUSION

Though there was no mortality, the extract of C. roseus higher than 300 mg can produce signs of biochemical and histopathological toxicity in liver, kidney and heart. It is recommended that lower doses than the studied ones should be used for treatment.

Effect of Exercise Order of Resistance Training on Strength Performance and Indices of Muscle Damage in Young Active Girls

Background

Exercise order is one of the key variables in designing resistance training (RT) that may affect physiological and functional muscle characteristics.

Objectives

The purpose of this research was to examine the effect of exercise order of RT on muscle strength, lactate dehydrogenase (LDH) and creatine kinase (CK) enzymes as indices of muscle damage in active young girls.

Patients and Methods

For this purpose, 24 active girls aged 20 - 30 years voluntarily participated in six weeks RT. The subjects were randomly assigned into three groups of large to small muscle group (SLM, n = 8), large to small group (LSM, n = 8) and control group (Co, n = 8). The RT performed in bench press, lat pull down, triceps with machine and biceps with barbell. Before and after RT, blood sample was collected to measure the level of LDH and CK enzymes activity.

Results

The result of analysis indicated that RT significantly increased the level of LDH enzymes in all three groups (P < 0.05). In addition, the result showed that six weeks of RT did not cause any significant change in CK (P > 0.05). However, there is no significant difference between SLM, LSM and control in CK and LDH after six weeks RT.

Conclusions

Both RT methods cause the same improvement on muscle strength and performance. Also muscle damage indices did not show sensitivity to the exercise order. Therefore, resistance training may be designed regardless of effect of exercise order on muscle damage.

Myristica fragrans Suppresses Tumor Growth and Metabolism by Inhibiting Lactate Dehydrogenase A

Most cancer cells predominantly produce ATP by maintaining a high rate of lactate fermentation, rather than by maintaining a comparatively low rate of tricarboxylic acid cycle, i.e., Warburg's effect. In the pathway, the pyruvate produced by glycolysis is converted to lactic acid by lactate dehydrogenase (LDH). Here, we demonstrated that water extracts from the seeds of Myristica fragrans Houtt. (MF) inhibit the in vitro enzymatic activity of LDH. MF effectively suppressed cell growth and the overall Warburg effect in HT29 human colon cancer cells. Although the expression of LDH-A was not changed by MF, both lactate production and LDH activity were decreased in MF-treated cells under both normoxic and hypoxic conditions. In addition, intracellular ATP levels were also decreased by MF treatment, and the uptake of glucose was also reduced by MF treatment. Furthermore, the experiment on tumor growth in the in vivo mice model revealed that MF effectively reduced the growth of allotransplanted Lewis lung carcinoma cells. Taken together, these results suggest that MF effectively inhibits cancer growth and metabolism by inhibiting the activity of LDH, a major enzyme responsible for regulating cancer metabolism. These results implicate MF as a potential candidate for development into a novel drug against cancer through inhibition of LDH activity.

[Not Quite] The Ketogenic Diet in a Pill

Researchers at Okayama University, Japan showed lactate dehydrogenase (LDH) inhibition suppresses neuronal excitation in vitro, reduces EEG discharges and seizures in rodent models, and may provide a novel mechanism for anticonvulsant medications in human patients.

Risk Factors for Mechanical Ventilation in Patients with Scrub Typhus Admitted to Intensive Care Unit at a University Hospital

Background

The purpose of this study was to evaluate the risk factors for mechanical ventilation in the patients with scrub typhus admitted to intensive care unit (ICU) at a university hospital.

Methods

We retrospectively selected and analyzed clinical data from the medical records of 70 patients (32 men, 38 women) admitted to the ICU with scrub typhus between 2004 and 2014. The patients had a mean±standard deviation age of 71.2±11.1 years and were evaluated in two groups: those who had been treated with mechanical ventilation (the MV group, n=19) and those who had not (the non-MV group, n=51). Mean ages of the MV group and the non-MV group were 71.2±8.3 years and 71.2±11.1 years, respectively.

Results

Significant differences between the two groups were observed with respect to acute respiratory failure (p=0.008), Acute Physiology and Chronic Health Evaluation (APACHE) II score (p=0.015), Sequential Organ Failure Assessment (SOFA) score (p=0.013), death (p=0.014), and ICU duration (p<0.01). Multivariate analysis indicated that the following factors were significantly associated with mechanical ventilation: acute respiratory failure (p=0.011), SOFA score (p=0.005), APACHE II score (p=0.011), platelet count (p=0.009), and lactate dehydrogenase (LDH) (p=0.011).

Conclusion

Thus, five factors-acute respiratory failure, SOFA score, APACHE II score, platelet count, and LDH-can be the meaningful indicators for mechanical ventilation for the patients with scrub typhus admitted to ICU.

Cardioprotection of 17β-estradiol against hypoxia/reoxygenation in cardiomyocytes is partly through up-regulation of CRH receptor type 2

Estrogens have been suggested to exert cardioprotection through maintaining endogenous cardioprotective mechanisms. In the present study, we investigated whether estrogens protect cardiomyocytes against hypoxia/reoxygenation (H/R) via modulating urocortins (UCNs) and their receptor corticotrophin-releasing hormone receptor type 2 (CRHR2). We found that 17β-estradiol (E2) enhanced UCN cardioprotection against H/R and increased CRHR2 expression in neonatal rat cardiomyocytes. E2 protected cardiomyocytes against H/R, which was impaired by CRHR2 antagonist or knockdown of CRHR2. Estrogen receptor α (ERα) antagonist treatment or ERα knockdown could abolish E2-induced CRHR2 up-regulation. Moreover, knockdown of Sp1 also attenuated E2-induced CRHR2 up-regulation. Ovariectomy resulted in down-regulation of CRHR2 and Sp-1 in myocardium of mice, which was restored by E2 or ERα agonist treatment. These results suggest that estrogens act on ERα to up-regulate CRHR2 expression in cardiomyocytes, thereby enhancing cardioprotection of UCNs against H/R.

Regulation of the activity of lactate dehydrogenases from four lactic acid bacteria

Despite high similarity in sequence and catalytic properties, the l-lactate dehydrogenases (LDHs) in lactic acid bacteria (LAB) display differences in their regulation that may arise from their adaptation to different habitats. We combined experimental and computational approaches to investigate the effects of fructose 1,6-bisphosphate (FBP), phosphate (Pi), and ionic strength (NaCl concentration) on six LDHs from four LABs studied at pH 6 and pH 7. We found that 1) the extent of activation by FBP (Kact) differs. Lactobacillus plantarum LDH is not regulated by FBP, but the other LDHs are activated with increasing sensitivity in the following order: Enterococcus faecalis LDH2 ≤ Lactococcus lactis LDH2 < E. faecalis LDH1 < L. lactis LDH1 ≤ Streptococcus pyogenes LDH. This trend reflects the electrostatic properties in the allosteric binding site of the LDH enzymes. 2) For L. plantarum, S. pyogenes, and E. faecalis, the effects of Pi are distinguishable from the effect of changing ionic strength by adding NaCl. 3) Addition of Pi inhibits E. faecalis LDH2, whereas in the absence of FBP, Pi is an activator of S. pyogenes LDH, E. faecalis LDH1, and L. lactis LDH1 and LDH2 at pH 6. These effects can be interpreted by considering the computed binding affinities of Pi to the catalytic and allosteric binding sites of the enzymes modeled in protonation states corresponding to pH 6 and pH 7. Overall, the results show a subtle interplay among the effects of Pi, FBP, and pH that results in different regulatory effects on the LDHs of different LABs.

Effect of HEMADO on Level of CK-MB and LDH Enzymes after Ischemia/Reperfusion Injury in Isolated Rat Heart

INTRODUCTION

Ischemia/Reperfusion (IR) injury mainly causes the increase of enzymes involved in myocytes injury including CK-MB (creatine kinase-MB) isoenzyme and LDH (lactate dehydrogenase). Leakage of CK-MB isoenzyme and LDH from myocardial tissues to blood is indicator of acute myocardial infarction. The aim of this study was to assess the effect of HEMADO on IR injury and its relationship with mitochondrial ATP-sensitive K+ channels (mitoKATP) in rat heart.

METHODS

Twenty eight male Wistar rats (250-300g) were divided into four groups (seven members in each group): control (without ischemia), I/R (with ischemia+without HEMADO), ischemia received HEMADO (HEMADO), ischemia received HEMADO and 5-HD (5-hydroxydecanoate, specific mitoKATP channel blocker) (HEMADO+5-HD). The animals were anesthetized and the hearts were quickly removed and mounted on Langendorff apparatus and perfused by Krebs-Henseleit solution under constant pressure and temperature of 37ºC. After 20 minutes of stabilization, ischemic groups were exposed to 40 minutes of global ischemia and consecutive 90 minutes of reperfusion.

RESULTS

IR injury increased the level of LDH and CK-MB in the collected coronary flow during 5 minutes since start of reperfusion. HEMADO reduced the enzymes' levels and using 5-HD abolished the effect of HEMADO.

CONCLUSION

Our findings indicated that HEMADO could protect the heart against ischemia-reperfusion injury by decreasing the CK-MB and LDH levels. The cardioprotective effect of HEMADO may be mediated in part by mitoKATP.

Seasonal Changes in Serum Testosterone, LDH Concentration and Semen Characteristics in Markhoz Goats

This experiment was conducted to study variations of serum testosterone and seminal characteristics of Markhoz male goats. Blood samples were obtained via jugular vein, and semen was collected by using an artificial vagina from 14 fertile male goats (2–3 years of age), at 15-day intervals starting on 15 July and ending on 30 October 2010 (during breeding and non-breeding season). Semen volume, total sperm (volume×concentration), live sperm (%), abnormal sperm (%) and semen pH were significantly superior during the late summer and early autumn (breeding season). Variation of sperm density, motility and progressive motility was not significant during the sampling period. The results presented show that the lowest and highest levels of lactate dehydrogenase in the seminal plasma were recorded in late October (2.82 U/ml) and in late August (4.81 U/ml), respectively. Moreover, the study indicated that the serum testosterone concentration was higher during late summer and early autumn (p<0.05) than at any other of sampling period. There were negative correlations between volume and sperm density (−0.135, p<0.05), and positive correlations between volume and percentage live sperm (0.224) and percentage progressive motility (0.194, p<0.01). Sperm density was correlated with live sperm (0.200, p<0.05) and progressive motility (0.202, p<0.01). The correlation between live sperm and progressive motility was 0.554 (p<0.01). Furthermore, the results in this study indicated a significant positive correlation between live sperm and LDH (0.450) and a negative correlation between sperm density and LDH concentration (−0.272) (p<0.01). Significant, but positive correlations were found between sperm motility and LDH (0.542) and testosterone concentration (0.522), respectively (p<0.05). In conclusion, this study demonstrated that the best obtained semen was collected in late summer (during decreasing photoperiod) and early autumn (September and October). This also coincides with the natural breeding season of Markhoz goats in Iran.