Lactate Dehydrogenase Enzyme Activity Research Articles

Quercetin ameliorates acetamiprid-inducedhepatotoxicity and oxidative stress

Introduction: Neonicotinoids are a new type of insecticides that have been introduced to the poison market during the last three decades. Acetamiprid (ACT) is a neonicotinoid and widely used for controlling pests. It targets the liver as a toxic agent and damages hepatic tissues through oxidative stress mechanisms. Quercetin is a flavonoid with potent antioxidant and hepatoprotective activity and protects tissues from oxidative damages. Thus, this study is aimed to assess the protective effect of quercetin on acetamiprid-induced hepatotoxicity. Methods: Thirty-six Wistar rats were classified into six groups including control, DMSO, ACT 20, ACT 40, quercetin, and ACT40+quercetin. All treatments were administered orally with gavage for 28 days. Alanine amino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) enzyme activity was measured in serum as biomarkers of hepatotoxicity. Lipid peroxidation, superoxide dismutase (SOD) enzyme activity and total thiol content were measured in hepatic tissues. Also, hepatic tissue sections were prepared and stained with hematoxylin and eosin and evaluated under optic microscope for any tissue injuries. Results: Findings showed that ACT, especially in high dose (40mg/kg), induced hepatic tissue destruction associated with increased hepatic enzyme activity, except ALP activity, in the serum. Besides, ACT increased the lipid peroxidation and decreased total thiol content and SOD activity, which indicates ACT-induced oxidative stress in hepatic tissues. Also, hepatic tissue injuries were observed in ACT-treated group. All these changes in liver were prevented by quercetin. Conclusion: Because of strong antioxidant properties, quercetin can cope effectively with ACT-induced hepatotoxicity.

Use of biomarkers in monitoring pollution status of urban rivers, Limpopo, South Africa.

This study investigated the use of enzymes and histology as potential biomarkers in Sand and Blood Rivers in Limpopo Province, South Africa. Physico-chemical parameters were analyzed at sites S1, S2, S3, S4, and S5 of the Sand River and sites B1 and B2 of the Blood River. Sites S1 and B1 were selected as the reference sites and located upstream of the Polokwane and Seshego wastewater treatment plants (WWTPs) effluent discharge points, respectively. Water quality parameters assessed were water temperature, dissolved oxygen (DO), biological oxygen demand (BOD), total dissolved solids (TDS), turbidity, ammonia, nitrogen, phosphorus, and pH. Sites downstream the WWTPs recorded elevated levels of nitrogen, phosphorus, and ammonia. DO, ammonia, nitrogen, and phosphorus were above the targeted water quality range (TWQR) for aquatic ecosystems. The Canadian council of ministers of the environment water quality index (CCME WQI) showed that the reference sites had good water condition while sites downstream (S2, B2, S3, and S4) had poor water condition. Acetylcholinesterase (AChE) enzyme activity in the brain of Clarias gariepinus from sites downstream was lower than those from sites upstream of the effluent discharge points. The liver of Clarias gariepinus from sites downstream showed higher lactate dehydrogenase (LDH) enzyme activity compared to fish caught at the reference sites. Furthermore, Clarias gariepinus from sites downstream showed a number of histological alterations in gills and liver than fish from upstream. Histological alterations observed in gills included fusion of the secondary lamellae, hyperplasia of the interlamellar, epithelial lifting of secondary lamellae, and hyperplasia of the secondary lamellae. In the liver, histological alterations observed included melanomacrophage centers (MMCs), macrovesicular steatosis, sinusoid congested with kupffer cells, nuclei pleomorphism, and vacuolation. The gill and liver indices were significantly lower at the reference sites compared to sites downstream. Evidently, AChE, LDH, and gill and liver histology can be used as early warning signs of aquatic degradation in rivers that are recipients of poorly treated sewage effluent.

Identification of nucleic acid aptamers against lactate dehydrogenase via SELEX and high-throughput sequencing.

Nucleic acid aptamers are small fragments of DNA or RNA molecules binding specifically to targets, which can be obtained through in vitro screening via systematic evolution of ligands by exponential enrichment (SELEX). Lactate dehydrogenase (LDH) is an important tumor marker, whose level in patients is of great significance for diagnosis of many diseases. Here, we report the identification of LDH aptamers by 9 rounds of screening from a length-mixed single-stranded DNA library using the SELEX technology. After the 3rd and 7th rounds of aptamer screening, affinity was significantly improved, and fluorescence quantitative analysis showed stronger affinity for the aptamers selected from the 7th to 9th rounds of screening. After high-throughput sequencing, motif analysis, and secondary structure prediction, we finally chose and further investigated 15 candidate LDH aptamer sequences with obvious differences in secondary structure in the 7th to 9th rounds of screening. Among them, LDH7-1, LDH7-9, LDH8-2, and LDH9-1 were shown to bind to LDH protein with high affinity and specificity with Kd < 25 nM. This study provides new ideas for rapid detection of LDH protein content and enzyme activity, thus contributing to the development of rapid medical detection.

Antimalarial effects of the hydroalcoholic extract of Allium paradoxum in vitro and in vivo.

Malaria still is the most fatal parasitic disease affecting 50% of the world's population. Although annual deaths attributed to malaria has reduced, crucial importance of its prevention and treatment remains a priority for health care systems and researchers. The worldwide increase in resistance to most common antimalarial drugs such as chloroquine, their unpleasant side effects and low efficiencies persuade researchers to prioritize finding alternative drugs including herbal medication from plant roots. The present study aimed to examine in vitro and in vivo effects of hydroalcoholic extract of herbal medicinal plant, Allium paradoxum, on growth rate in Plasmodium falciparum and Plasmodium berghei. The cytotoxicity assay was performed for hydroalcoholic extract of A. paradoxum. The 3D7 strain of P. falciparum was cultured. The IC50 assay and enzymatic activity of lactate dehydrogenase were performed. BALB/c mice were infected with P. berghei in vivo. Toxicity and histopathological changes in the tissues of liver and kidney were also examined. The highest efficacy of A. paradoxum extract was observed at 80μg/mL in P. falciparum culture resulting in 60.43% growth inhibition compared to control groups. The significantly highest parasite growth inhibition with 88.71% was seen in the mice infected with P. berghei when administered with 400mg/kg extract compared to control groups. No significant changes in the liver and kidney cells were observed between experimental and control groups. The study showed that A. paradoxum extract exhibited significant antimalarial properties in vitro on P. falciparum and in vivo in mice infected with P. berghei. There was no significant toxicity in the liver and kidney of the treated mice.

Preparation, stability and commutability of candidate reference materials for lactate dehydrogenase (LDH)

BackgroundLactate dehydrogenase (LDH) is a key enzyme that functions as a marker of cell damage. Its activity can be measured by a variety of laboratory methods. To eliminate inter-method bias and enhance equivalence among different measurement procedures, LDH detection needs to be standardized. MethodsOptimized sequences coding for lactate dehydrogenase subunit A (LDH-A) and subunit B (LDH-B) were synthesized and cloned into the pRSFDuet vector, and then the constructed 6His-LDHA-pRSFDuet, 6His-LDHB-pRSFDuet, and 6His-LDHA-LDHB-pRSFDuet plasmids were transformed into Escherichia coli BL21 (DE3) for expression. The enzyme activity and specific activity of recombinant LDHs were detected. Electrophoresis of LDH isoenzymes was performed. The stability of recombinant LDHs and serum LDH was evaluated. Commutability of recombinant LDH-B was studied by the IFCC reference method and six routine methods. ResultsThree plasmids were constructed and three highly concentrated recombinant LDH isoenzymes were obtained. The specific activities of LDH-A, LDH-AB, and LDH-B were 18.08 U/mg, 21.74 U/mg, and 14.18 U/mg, respectively. There was a desirable linear correlation between the activities of recombinant LDH isoenzymes and their protein concentrations. Electrophoresis of LDH isoenzymes showed that the recombinant LDH-B corresponded to LDH1 and it demonstrated good stability at 4 °C and 25 °C for 5 weeks. LDH-B formulations in saline-bovine serum albumin solution and human serum matrix were commutable for six routine methods. ConclusionHuman recombinant LDH-B has great potential to become an improved and less expensive standard or reference material in external quality assessment for clinical LDH measurement.

Enzymatic Markers of Pulmonary Inflammation in Tracheal Wash Fluid in Racehorses: Alkaline Phosphatase and Lactate Dehydrogenase

Background: Diagnosis of the lower airway diseases (LAD) in horses relies on clinical signs, endoscopic examination and cytologic evaluation of lower respiratory tract flushing fluids as well. Specific enzyme activities in respiratory tract fluids of horses could be used as useful indicators in lower airway disorders. The main goal of the study was to evaluate the diagnostic usefulness of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) enzyme activites in tracheal wash (TW) fluids of horses with lower respiratory tract inflammation and/or damage and also in distinguishing of non-septic and septic inflammation in racehorses with LAD.Materials, Methods &amp; Results: A cross-sectional study was conducted in racehorses. TW fluid samples were obtained from 83 racehorses (71 with lower airway diseases and 12 healthy controls) for the study. The One-Way ANOVA Test was used for the significance analysis of the differences between the groups in showing the normal distribution of blood serum ALP and LDH properties. Kruskal Wallis H Test and Tamhane T2 test were used for the significance analysis of the differences between the groups of tracheal ALP and LDH properties, which were not normally distributed. The sampled horses were classified into 3 groups as healthy control, non septic neutrophilic inflammation (NS-LAD) and septic neutrophilic inflammation (S-LAD) according to the tracheal mucus scores determined during endoscopic examination, clinical signs, cytologic and bacteriologic examination of collected TW samples. According to cytology results normal neutrophil levels (&lt; 20%) were determined in the heatlhy control group (14.5%). However, increased neutrophil levels (≥ 20% and ≥ 80%) were encountered in the NS-LAD (61.4%) and S-LAD (24.1%) groups respectively. Also, the signs of degenerative changes and presence of intracellular bacteria in the neutrophil cells in the S-LAD group was observed. Bacteriologic analysis of the samples revealed Streptococcus equi subsp. zooepidemicus was the most prevalent agent (85.6%) followed by Escherichia coli (4.8%), Staphylococcus aureus (4.8%) and Klebsiella pneumoniae (4.8%). ALP and LDH enzyme activities of TW fluid were found to be significantly higher in racehorses with LAD compared with healthy controls (P &lt; 0.01). On the other hand, a significant difference was also determined for LDH levels between NS-LAD and S-LAD cases determining with cytological and bacteriological examination (P &lt; 0.01). No statistically significant difference was found between NS-LAD and S-LAD group. Serum ALP and LDH levels of racehorses revealed no significant difference between each study groups.Discussion: Respiratory system diseases have been known to be one of the main causes of training disruption and interruption of racing events in racehorses. Specifically, LAD is the most frequently diagnosed disorder in racehorses evaluated for poor performance. In the present study established for determining the usefulness of ALP and LDH enzyme levels in the TW samples of horses with lower respiratory tract inflammatory disorders. It was concluded that ALP and LDH enzyme activities of TW fluid could be considered as indicators of pulmonary inflammation and/or damage and LDH enzyme activity is thought to be useful in distinguishing neutrophilic non-septic and septic pulmonary inflammation in racehorses with LAD. On the other hand, data obtained from the study indicated that TW fluid ALP activity was not enough statistically to differenatiate horses with non-septic and septic lower airway inflammation.

Use of Chou’s 5-steps Rule to Study the Effect of Cereal Dietary Protein on Liver and Coronary Heart Disease Prevention

Background: The liver is a vital organ in the human body involved in the metabolic processes. The liver can be damaged due to factors such as protein deficiency, viral infection, as well as consumption of alcohol, chemical contaminants, and adulterated food. High blood cholesterol, high blood pressure, diabetes, lack of exercise, poor diet, obesity and cigarette smoking are the major risk factors for stroke, heart attack and coronary heart disease (CHD). In medical science, several synthetic drugs have been discovered and used for the treatment of people suffering from liver injury and CHD, but these are not always effective and sometimes difficult to manage by medical therapies and also found to be accompanied by other side effects. Objective: The study aimed to critically review the recent research and studies of epidemiological and randomized controlled trials to find out the effective cereal protein as an alternative preventive food to reduce the risk of CHD and protect the liver from viral hepatic diseases, focusing on daily food intake, body weight, liver weight, serum enzyme activities and cholesterols. Methods: A few of the data from our experiment were used. A literature search was performed for a reliable source of published research articles, review papers, and epidemiological and randomized controlled trials on the effects of cereal protein on animals and human intervention on Google, Google scholar, Redcube, Endnote, Scopus, SpringerDirect.com, PubMed and Web of Science. Then, the data was organized, summarized and analyzed. Results: In medical science, serum enzyme activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and lipid peroxidation stress malondialdehyde (MDA) are commonly used as biochemical markers of the liver-damaging agents. Blood cholesterols (total cholesterol-TC, triglyceride-TG, low-density lipoprotein cholesterol-LDLC and highdensity lipoprotein cholesterol-HDLC) are used as the markers of heart diseases. The review shows that daily food intake and body weight data are not significantly differed among normal diet, casein (CAS) and cereals protein. The millet and wheat protein increase the liver weight, whereas the rice protein lowers the liver weight. The intake of cereal protein significantly reduces the activities of serum AST, ALT, LDH, MDA, TC, TG and LDLC, whereas it increases the HDLC. Conclusion: Experimental, review and randomized controlled trials (RCTs) data confirm that cereal protein appears to be beneficial in reducing the hepatic liver injury and CHD by maintaining body weight, liver weight, blood pressure, serum enzyme activities of AST, ALT and LDH, lipid peroxidation stress MDA and cholesterol concentrations both in plasma and liver.

Comparative Evaluation of Lactate Dehydrogenase (Ldh) Enzyme Activity in Saliva of Periodontitis Patients with Or Without Diabetes

Comparative Evaluation of Lactate Dehydrogenase (Ldh) Enzyme Activity in Saliva of Periodontitis Patients with Or Without Diabetes

A brain‐infecting parasite impacts host metabolism both during exposure and after infection is established

Abstract Metabolic costs associated with parasites should not be limited to established infections. Even during initial exposure to questing and attacking parasites, hosts can enact behavioural and physiological responses that could also incur metabolic costs. However, few studies have measured these costs directly. Hence, little is known about metabolic costs arising from parasite exposure. Furthermore, no one has yet measured whether and how previous infection history modulates metabolic responses to parasite exposure. Here, using the California killifish Fundulus parvipinnis and its brain‐infecting parasite Euhaplorchis californiensis, we quantified how killifish metabolism, behaviour and osmoregulatory phenotype changed upon acute exposure to parasite infectious stages (i.e. cercariae), and with long‐term infection. Exposure to cercariae caused both naïve and long‐term infected killifish to acutely increase their metabolic rate and activity, indicating detection and response to parasite infectious stages. Additionally, these metabolic and behavioural effects were moderately stronger in long‐term infected hosts than naïve killifish, suggesting that hosts may develop learned behavioural responses, nociceptor sensitization and/or acute immune mechanisms to limit new infections. Although established infection altered the metabolic response to parasite exposure, established infection did not alter standard metabolic rate, routine metabolic rate, maximum metabolic rate, aerobic scope or citrate synthase enzyme activity. Unexpectedly, established infection reduced lactate dehydrogenase enzyme activity in killifish brains and relative Na+/K+‐ATPase abundance in gills, suggesting novel mechanisms by which E. californiensis may alter its hosts' behaviour and osmoregulation. Thus, we provide empirical evidence that parasites can disrupt the metabolism of their host both during parasite exposure and after infection is established. This response may be modulated by previous infection history, with probable knock‐on effects for host performance, brain energy metabolism, osmoregulation and ecology. A free Plain Language Summary can be found within the Supporting Information of this article.

Complex toxin binder mycotox® ng influence on the hepatotoxic effect of aflatoxin B1 in experimental treated goslings

Abstarct. The aim of the present investigation was to evaluate the effects of aflatoxin B1 and Mycotox NG applied either independently or together, on blood total protein, albumin, blood glucose, total bilirubin, triglycerides, cholesterol, enzyme activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AP), gamma-glutamyl transferase (γ GT), lactate dehydrogenase (LDH) and changes in liver morphology. At the same time, the potential of supplementation of feed with a mycosorbent (Mycotox NG) was evaluated. Experiments were carried out with 40 1-day-old Toulouse geese from mixed sexes divided into one control and three treatment groups (n=10). Groups were as followed: Group I – control (0 mg/kg AFB1 not supplemented with Mycotox NG); Group II (0.5 g/kg Mycotox NG), Group III (0.5 mg/kg AFB1) and Group IV (0.5 mg/kg AFB1 and 0.5 g/kg Mycotox NG). In this study, commercially available geese of Toulouse strain were reared from day one to forty two days in the deep litter system of management and the birds were divided into four groups. Normal feed tested free of aflatoxin (AFB1), was given to the control (Group – 1). 0.5 g/kg Mycotox was supplemented with the feed to Group 2, Aflatoxin (0.5 mg/kg feed) was supplemented with the feed to Group 3 and Mycotox Ng (0.5 g/kg feed) + 0.5 mg/kg feed AFB1 was supplemented with the feed to Group 4. The duration of the experiments was 42 days. The monitored blood chemical parameters were analysed on post treatment days 21 and 42. In birds treated only with AFB1, (group III) increased blood activities of studied enzymes. At the same time, blood total protein, albumin, cholesterol, glucose and triglycerides were reduced as compared to controls. The observed histopathological changes in the liver consisted in various extent of dystrophy (congestion, vacuolar and granular dystrophy, round cell proliferation, necrobiotic changes, hyperplasia of gallbladder epithelium). The addition of mycosorbent (Mycotox NG) to the feed of Groups IV reduced substantially the changes in blood chemistry and the severity and frequency of liver histological lesions. The addition of mycosorbent (Mycotox NG) to the feed of Groups IV reduced substantially the changes in blood chemistry and the severity and frequency of liver histological lesions.

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.

Treatment of platelet concentrates with the L-carnitine modulates platelets oxidative stress and platelet apoptosis due to mitochondrial reactive oxygen species reduction and reducing cytochrome C release during storage.

Platelet concentrate (PC) transfusion is administrated to reduce the hemostatic complications in patients with thrombocytopenia. Strength platelet against oxidative stress conditions lead to decrease in platelet storage lesion (PSL). This study was aimed to evaluate L-carnitine (LC) effects on platelet oxidative stress and platelet apoptosis during storage time. PC bags were randomly selected and each bag was divided into two equal parts. L-carnitine was added to test groups. Normal saline was added to control groups. Platelets count, mean platelet volume (MPV), pH, Platelet aggregation, nitric oxide metabolism (nitric/nitrate), total antioxidant capacity (TAC), malondealdehyde concentration (MDA), lactate dehydrogenase (LDH) enzyme activity, mitochondrial reactive oxygen species (ROS) and cytochrome C releasing were assayed by standard methods in 1, 3, 5 and 7days of platelet storage. LDH enzyme activity was increased during storage but it had lower level in L-carnitine-treated platelets. LC treatment led to reduction in MDA concentration (3.35 ± 0.98 vs 5.3 ± 1.32, p = 0.003 and 6.52 ± 1.88 vs 5.67 ± 1.25, p = 0.005 for day 5 and day 7 respectively). Increased level of TAC was detected in LC-treated platelets in comparison to control (0.29 ± 0.06 vs 0.21 ± 0.05, p = 0.008 and 0.22 ± 0.03 vs 0.16 ± 0.03, p = 0.003 for day 5 and day 7 respectively). Interestingly, mitochondrial ROS and cytochrome C releasing was significantly lower in LC-treated versus control group during platelet storage. L-carnitine not only decreases mitochondrial ROS but also reduces cytochrome C releasing in PCs during storage. It might be considered as safe additive to decrease PSL in the future.

Acute effects of neonicotinoid insecticides on Mytilus galloprovincialis: A case study with the active compound thiacloprid and the commercial formulation calypso 480 SC

Pesticides can enter aquatic environments potentially affecting non-target organisms. Unfortunately, the effects of such substances are still poorly understood. This study investigated the effects of the active neonicotinoid substance thiacloprid (TH) and the commercial product Calypso 480 SC (CA) (active compound 40.4% TH) on Mytilus galloprovincialis after short-term exposure to sublethal concentrations. Mussels were tested for seven days to 0, 1, 5 and 10 mg L−1 TH and 0, 10, 50 and 100 mg L−1 CA. For this purpose, several parameters, such as cell viability of haemocytes and digestive cells, biochemical haemolymph features, superoxide dismutase (SOD) and catalase (CAT) enzymatic activity of gills and digestive gland, as well as histology of such tissues were analysed. The sublethal concentrations of both substances lead to abatement or completely stopping the byssal fibres creation. Biochemical analysis of haemolymph showed significant changes (P < 0.01) in electrolytes ions (Cl−, K+, Na+, Ca2+, S-phosphor), lactate dehydrogenase (LDH) enzyme activity and glucose concentration following exposure to both substances. The TH-exposed mussels showed significant imbalance (P < 0.05) in CAT activity in digestive gland and gills. CA caused significant decrease (P < 0.05) in SOD activity in gills and in CAT activity in both tissues. Results of histological analyses showed severe damage in both digestive gland and gills in a time- and concentration-dependent manner. This study provides useful information about the acute toxicity of a neonicotinoid compound and a commercial insecticide on mussels. Nevertheless, considering that neonicotinoids are still widely used and that mussels are very important species for marine environment and human consumption, further researches are needed to better comprehend the potential risk posed by such compounds to aquatic non-target species.

Multi-Biomarker Assessment in Common Carp (Cyprinus carpio, Linnaeus 1758) Liver after Acute Chlorpyrifos Exposure

The excessive use of pesticides at different stages of crop production can pose a great danger to the aquatic environment, and particularly to fish. The purpose of the present work was to assess the negative effects of chlorpyrifos (CPF) on the liver histological architecture and the activities of marker enzymes in common carp (Cyprinus carpio Linnaeus, 1758), by applying a multi-biomarker technique. The tested insecticide is categorized as a priority pollutant in surface waters in terms of Directive 2013/39/EU. The carps were exposed to different and environmentally relevant CPF concentrations for 72 h (a short-term acute experiment). The results showed that the tested insecticide alters the liver histological structure, causing degenerative lesions, such as granular and vacuolar degeneration; necrobiotic alterations and necrosis, as well as changes in the circulatory system. In addition, CPF induces changes in the enzymatic activity of lactate dehydrogenase (LDH), aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT), cholinesterase (ChE), glutathione peroxidase (GPx) and catalase (CAT). The results from such experimental set ups could be successfully used in the legislation related to the protection of water bodies from contamination, in areas with intensive application of plant protection products used in agricultural practices, and also in implementing the Water Frame Directive by using multi-biomarker approaches.

The protective effect of fluted pumpkin seeds against atrazine-induced testicular injury

The present study evaluated the protective effect of fluted pumpkin seeds (FPS) on atrazine (ATZ)-induced testicular damage. Twenty adult male Wistar rats were divided into four groups of five animals each. The control animals (Group A) received corn oil (2 mL/kg body weight), Group B animals received 50 mg ATZ/kg body weight by gavage, while Groups C and D received 50 mg ATZ/kg body weight once a week in addition to the gavage of 25 mg FPS/kg body weight and 50 mg FPS/kg body weight respectively for 60 days. The results showed that testicular myeloperoxidase activity and nitrite concentration were decreased in all groups compared to the control value. The increase in malondialdehyde and decrease in glutathione concentrations in group B were abrogated in group C (p < 0.05) but not in group D animals. The increase in γ-glutamyl transpeptidase and decrease in lactate dehydrogenase enzyme activities in the group B animals were also normalized to control values in group C but not in group D animals. Interestingly, the testis of the group D animals showed massive depletion of germ cells and the diameter of the seminiferous tubules of these animals were decreased compared to all other groups. However, the number of motile sperms, abnormal sperms and sperm count in Group D animals were similar to the ATZ-treated animals and lower than control values. In conclusion, FPS protected against ATZ-induced testicular damage but can also harm the testis at a higher dose.

Lactate dehydrogenase expression modulates longevity and neurodegeneration in Drosophila melanogaster.

Lactate dehydrogenase (LDH) catalyzes the conversion of glycolysis-derived pyruvate to lactate. Lactate has been shown to play key roles in brain energetics and memory formation. However, lactate levels are elevated in aging and Alzheimer’s disease patients, and it is not clear whether lactate plays protective or detrimental roles in these contexts. Here we show that Ldh transcript levels are elevated and cycle with diurnal rhythm in the heads of aged flies and this is associated with increased LDH protein, enzyme activity, and lactate concentrations. To understand the biological significance of increased Ldh gene expression, we genetically manipulated Ldh levels in adult neurons or glia. Overexpression of Ldh in both cell types caused a significant reduction in lifespan whereas Ldh down-regulation resulted in lifespan extension. Moreover, pan-neuronal overexpression of Ldh disrupted circadian locomotor activity rhythms and significantly increased brain neurodegeneration. In contrast, reduction of Ldh in neurons delayed age-dependent neurodegeneration. Thus, our unbiased genetic approach identified Ldh and lactate as potential modulators of aging and longevity in flies.

Early Detection of Pancreatic Intraepithelial Neoplasias (PanINs) in Transgenic Mouse Model by Hyperpolarized 13C Metabolic Magnetic Resonance Spectroscopy.

While pancreatic cancer (PC) survival rates have recently shown modest improvement, the disease remains largely incurable. Early detection of pancreatic cancer may result in improved outcomes and therefore, methods for early detection of cancer, even premalignant lesions, may provide more favorable outcomes. Pancreatic intraepithelial neoplasias (PanINs) have been identified as premalignant precursor lesions to pancreatic cancer. However, conventional imaging methods used for screening high-risk populations do not have the sensitivity to detect PanINs. Here, we have employed hyperpolarized metabolic imaging in vivo and nuclear magnetic resonance (1H-NMR) metabolomics ex vivo to identify and understand metabolic changes, towards enabling detection of early PanINs and progression to advanced PanINs lesions that precede pancreatic cancer formation. Progression of disease from tissue containing predominantly low-grade PanINs to tissue with high-grade PanINs showed a decreasing alanine/lactate ratio from high-resolution NMR metabolomics ex vivo. Hyperpolarized magnetic resonance spectroscopy (HP-MRS) allows over 10,000-fold sensitivity enhancement relative to conventional magnetic resonance. Real-time HP-MRS was employed to measure non-invasively changes of alanine and lactate metabolites with disease progression and in control mice in vivo, following injection of hyperpolarized [1-13C] pyruvate. The alanine-to-lactate signal intensity ratio was found to decrease as the disease progressed from low-grade PanINs to high-grade PanINs. The biochemical changes of alanine transaminase (ALT) and lactate dehydrogenase (LDH) enzyme activity were assessed. These results demonstrate that there are significant alterations of ALT and LDH activities during the transformation from early to advanced PanINs lesions. Furthermore, we demonstrate that real-time conversion kinetic rate constants (kPA and kPL) can be used as metabolic imaging biomarkers of pancreatic premalignant lesions. Findings from this emerging HP-MRS technique can be translated to the clinic for detection of pancreatic premalignant lesion in high-risk populations.

22β-hydroxytingenone reduces proliferation and invasion of human melanoma cells

Melanoma is a skin cancer with high invasive potential and high lethality. Considering that quinonemethide triterpenes are described as promising anticancer agents, the aim of this study was to evaluate the effect of 22β-hydroxytingenone (22-HTG) against human melanoma cells. Alamar blue assay was performed in order to evaluate its cytotoxic effect. Thus, subtoxic concentrations (1.0, 2.0, and 2.5 μM) were used to evaluate the effect of this compound on proliferation, migration, metabolism, and invasion. IC50 value against SK-MEL-28 cell line was 4.35, 3.72, and 3.29 μM after 24, 48, and 72 h of incubation, respectively. 22-HTG reduced proliferation, migration and invasion by melanoma cells, with decreased activity of metalloproteinases (MMP-2 and MMP-9). Futhermore, 22-HTG decreased expression of lactate dehydrogenase (LDHA), an enzyme associated with cell metabolism. Howerver, the small reduction in LDHA enzyme activity must have occurred by the cytotoxic effect of 22-HTG. According to the results, 22-HTG interferes with important characteristics of cancer, with anti-proliferative, and anti-invasive effect against melanoma cells. The data suggest that 22-HTG is an effective substance against melanoma cells and it should be considered as a potential anticancer agent.

Simultaneous Metabolic and Perfusion Imaging Using Hyperpolarized 13C MRI Can Evaluate Early and Dose-Dependent Response to Radiation Therapy in a Prostate Cancer Mouse Model

To investigate use of a novel imaging approach, hyperpolarized (HP) 13C magnetic resonance imaging (MRI) for simultaneous metabolism and perfusion assessment, to evaluate early and dose-dependent response to radiation therapy (RT) in a prostate cancer mouse model. Transgenic Adenocarcinoma of Mouse Prostate (TRAMP) mice (n = 18) underwent single-fraction RT (4-14 Gy steep dose across the tumor) and were imaged serially at pre-RT baseline and 1, 4, and 7 days after RT using HP 13C MRI with combined [1-13C]pyruvate (metabolic active agent) and [13C]urea (perfusion agent), coupled with conventional multiparametric 1H MRI including T2-weighted, dynamic contrast-enhanced, and diffusion-weighted imaging. Tumor tissues were collected 4 and 7 days after RT for biological correlative studies. We found a significant decrease in HP pyruvate-to-lactate conversion in tumors responding to RT, with concomitant significant increases in HP pyruvate-to-alanine conversion and HP urea signal; the opposite changes were observed in tumors resistant to RT. Moreover, HP lactate change was dependent on radiation dose; tumor regions treated with higher radiation doses (10-14 Gy) exhibited a greater decrease in HP lactate signal than low-dose regions (4-7 Gy) as early as 1 day post-RT, consistent with lactate dehydrogenase enzyme activity and expression data. We also found that HP [13C]urea MRI provided assessments of tumor perfusion similar to those provided by 1H dynamic contrast-enhanced MRI in this animal model. However, apparent diffusion coefficien , a conventional 1H MRI functional biomarker, did not exhibit statistically significant changes within 7 days after RT. These results demonstrate the ability of HP 13C MRI to monitor radiation-induced physiologic changes in a timely and dose-dependent manner, providing the basic science premise for further clinical investigation and translation.

The Impact of Aspirin Intake on Lactate Dehydrogenase, Arterial Stiffness, and Oxidative Stress During High-Intensity Exercise: A Pilot Study.

Aspirin is a common nonsteroidal anti-inflammatory drug used to reduce fever, pain, and inflammation. However, aspirin’s anti-inflammatory properties may also prevent increased levels of blood lactate dehydrogenase, vascular arterial stiffness and oxidative stress induced by high-intensity exercise. The purpose of this study was to investigate the effects of 4 weeks of aspirin supplementation on lactate dehydrogenase activity, lactate, arterial stiffness, and antioxidant capacity during high-intensity exercise in Taekwondo athletes. Participants were randomly divided into two groups: aspirin supplementation (n = 10) and placebo-control (n = 10). Blood levels of lactate dehydrogenase (LDH) enzyme activity and lactate were assessed to examine muscle damage and carotid-to-radial pulse wave velocity and the augmentation index were measured to examine arterial stiffness. Blood levels of superoxide dismutase, malondialdehyde, and glutathione peroxidase were assessed to determine antioxidant capacity and levels of oxidative stress. There were significant group × time interactions for enzyme activity of LDH (Δ-60 ± 24.36 U/L) and carotid-to-radial pulse wave velocity (Δ-1.33 ± 0.54 m/s), which significantly decreased (p < 0.05) following aspirin supplementation compared to placebo-control. Superoxide dismutase (Δ359 ± 110 U/gHb) and glutathione peroxidase (Δ28.2 ± 10.1 U/gHb) significantly decreased while malondialdehyde (0Δ3.0 ± 0.1 mmol/mL) significantly increased (p < 0.05) in the placebo-control group compared to the supplementation group. However, there were no changes in lactate concentration levels or augmentation index. These results reveal that low-dose aspirin supplementation would be a useful supplementation therapy to prevent high-intensity exercise training-induced increases in oxidative damage, inflammation, skeletal muscle fatigue, and arterial stiffness in elite Taekwondo athletes.