Lactate metabolism in neurodegenerative diseases

Lactate,a byproduct of glycolysis,was thought to be a metabolic waste until the discovery of the Warburg effect.Lactate not only functions as a metabolic substrate to provide energy but can also function as a signaling molecule to modulate cellular functions under pathophysiological conditions.The Astrocyte-Neuron Lactate Shuttle has cla rified that lactate plays a pivotal role in the central nervous system.Moreover,protein lactylation highlights the novel role of lactate in regulating transcription,cellular functions,and disease development.This review summarizes the recent advances in lactate metabolism and its role in neurodegenerative diseases,thus providing optimal pers pectives for future research.

Lactate:a prospective target for therapeutic intervention in psychiatric disease

Although antipsychotics that act via monoaminergic neurotransmitter modulation have considera ble therapeutic effect,they cannot completely relieve clinical symptoms in patients suffering from psychiatric disorde rs.This may be attributed to the limited range of neurotransmitters that are regulated by psychotropic drugs.Recent findings indicate the need for investigation of psychotropic medications that target less-studied neurotransmitte rs.Among these candidate neurotransmitters,lactate is developing from being a waste metabolite to a glial-neuronal signaling molecule in recent years.Previous studies have suggested that cerebral lactate levels change considerably in numerous psychiatric illnesses;animal experiments have also shown that the supply of exogenous la ctate exerts an antidepressant effect.In this review,we have described how medications targeting newer neurotransmitte rs offer promise in psychiatric diseases;we have also summarized the advances in the use of lactate(and its corresponding signaling pathways)as a signaling molecule.In addition,we have described the alterations in brain lactate levels in depression,anxiety,bipolar disorder,and schizophrenia and have indicated the challenges that need to be overcome before brain lactate can be used as a therapeutic target in psychopharmacology.

Effects of potassium lactate on sensory attributes,bacterial community succession and biogenic amines formation in Rugao ham

To deepen the understanding in the effect of potassium lactate on the sensory quality and safety of Rugao ham,sensory attributes,physicochemical parameters,total volatile basic nitrogen(TVBN),microorganism community and biogenic amines of Rugao ham manufactured with different potassium lactate levels(0%,0.5%,1%,2%)were investigated;the relationship between microbial community and the formation of TVBN and biogenic amines was further evaluated.With the increase of potassium lactate from 0%to 2%,the increased sensory scores and the decreased total aerobic bacterial count and TVBN were observed;the abundance of Staphylococcus increased,while the content of Halomonas decreased.LDA effect size(LEf Se)and correlations analysis showed that Staphylococcus equorum and Lactobacillus fermentum could be the key species to improve sensory scores and decrease biogenic amines and TVBN.Metabolic pathway analysis further showed that amino acids metabolism and nitrogen metabolism were mainly involved in decreasing TVBN and biogenic amines in the treatment of 2%potassium lactate.

Reversed-Phase-HPLC Assay Method for Simultaneous Estimation of Sorbitol, Sodium Lactate, and Sodium Chlorides in Pharmaceutical Formulations and Drug Solution for Infusion

A rapid, straightforward, sensitive, efficient, and cost-effective reverse-phase high-performance liquid chromatographic method was employed for the simultaneous determination of Sorbitol, Sodium Lactate, and Chlorides in a drug solution for infusion. Sorbitol, Sodium lactate, and Chloride are all officially recognized in the USP monograph. Assay methods are provided through various techniques, with titrations being ineffective for trace-level quantification. Alternatively, IC, AAS, and ICP-MS, though highly accurate, are costly and often unavailable to most testing facilities. When considering methods, it’s important to prioritize both quality control requirements and user-friendly techniques. A simple HPLC simultaneous method was developed for the quantification of Chlorides, Sorbitol, and Sodium Lactate with a shorter run time. The separation utilized a Shimpack SCR-102(H) ion exclusion analytical column (7.9 mm × 300 mm, 7 μm), with a flow rate of 0.6 mL per min. The column compartment temperature was maintained at 40°C, and the injection volume was set at 10 μL, with detection at 200 nm. All measurements were conducted in a 0.1% solution of phosphoric acid. The analytical curves demonstrated linearity (r > 0.9999) in the concentration range of 0.79 to 3.8 mg per mL for Sodium Lactate (SL), 0.16 to 0.79 mg per mL for Sodium Chloride (SC), and 1.5 to 7.2 mg per mL for Sorbitol. Validation of the developed method followed the guidelines of the International Conference on Harmonization (ICH Q2B) and USP. The method exhibited precision, robustness, accuracy, and selectivity. In accelerated stability testing over 6 months, no significant variations were observed in organoleptic analysis and pH. Consequently, the developed method is deemed suitable for routine quality control analyses, enabling the simultaneous determination of Sodium Lactate, Sodium Chloride, and Sorbitol in pharmaceutical formulations and infusions.

Lactate Decreases Bortezomib Sensitivity and Predicts Poor Clinical Outcomes of Multiple Myeloma

Objective:Metabolic disorders are regarded as hallmarks of multiple myeloma(MM)and are responsible for rapid cancer cell proliferation and tumor growth.However,the exact biological roles of metabolites in MM cells have not been fully explored.This study aimed to explore the feasibility and clinical significance of lactate for MM and investigate the molecular mechanism of lactic acid(Lac)in the proliferation of myeloma cells and cell sensitivity to bortezomib(BTZ).Methods:Metabolomic analysis of the serum was carried out to obtain metabolites expression and clinical characteristics in MM patients.The CCK8 assay and flow cytometry were used to detect cell proliferation,apoptosis,and cell cycle changes.Western blotting was used to detect the potential mechanism and apoptosis-and cycle-related protein changes.Results:Lactate was highly expressed in both the peripheral blood and bone marrow of MM patients.It was significantly correlated with Durie-Salmon Staging(DS Staging)and the International Staging System(ISS Staging)and the serum and urinary involved/uninvolved free light chain ratios.Patients with relatively high lactate levels had a poor treatment response.Moreover,in vitro experiments showed that Lac could promote the proliferation of tumor cells and decrease the proportion of G0/G1-phase cells,which was accompanied by an increased proportion of S-phase cells.In addition,Lac could decrease tumor sensitivity to BTZ by disrupting the expression of nuclear factor kappa B subunit 2(NFκB2)and Re1B.Conclusion:Metabolic changes are important in MM cell proliferation and treatment response;lactate could be used as a biomarker in MM and as a therapeutic target to overcome cell resistance to BTZ.

Correlation of umbilical cord blood pH,base deficit,and lactate levels with outcomes of hypoxic newborns:A prospective study

Objective:To determine the association of the three umbilical cord blood parameters:umbilical cord pH,base deficit,and lactate levels,with neonatal outcomes.Methods:This prospective observational study was conducted from April 2021 to September 2022 with 100 term and late preterm(>35 weeks)neonates whose umbilical cord blood pH was<7.10,Apgar score was<7 at 1 min,and required positive pressure ventilation.Umbilical cord blood was assessed for pH,base deficit,and blood lactate levels.The neonatal outcomes of neonatal intensive care unit admission,Apgar score at 1 min,and Apgar score at 5 min were assessed.Results:The mean of umbilical cord blood pH was 7.04±0.07,mean base deficit was(−9.3±3.9)mmol/L,and mean lactate levels were(6.51±2.29)mmol/L.Neonatal intensive care unit(NICU)admission was needed in 78(78%)neonates.The mean NICU stay length was(2.4±2.2)days ranging from 0 to 12 days with a median of 2 days.Univariate analysis showed no significant difference in cord blood pH(P=0.736)and base deficit(P=0.393)between neonates without NICU admission and neonates who required NICU admission,but lactate level was significantly higher in neonates who required NICU admission(P<0.001).There was no significant difference in cord blood pH(P=0.400)and base deficit(P>0.999)between neonates with Apgar scores 4-7 at 1 min and neonates with Apgar scores<4,but lactate level was significantly higher in neonates with Apgar scores<4 at 1 min(P<0.001).Conclusions:Umbilical cord blood pH,base deficit,and lactate levels are useful novel markers showing a significant correlation with neonatal intensive care unit admission and adverse neonatal morbidities among hypoxic newborns.Overall,lactate was a better predictor of adverse neonatal outcomes as compared to umbilical cord blood pH and base deficit.

Role of cerebrospinal fluid lactate in diagnosing meningitis in critically ill patients

BACKGROUND Meningitis is a life-threatening clinical condition associated with high mortality and morbidity.Early diagnosis and specific treatment may improve outcomes.Lack of specific clinical signs or tests make the diagnosis challenging.AIM To assess the efficacy of cerebrospinal fluid(CSF)lactate in diagnosing meningitis in critically ill patients.METHODS A prospective,observational cohort study was carried out in a neuro-medical intensive care unit(ICU)over a 22 mo period.Adult patients,with suspected meningitis admitted in ICU,were serially recruited.Patients who refused consent,those with peripheral sensorineural deficit,or with any contraindication to lumber puncture were excluded.CSF cytology,bio-chemistry,lactates,culture and polymerase chain reaction based meningo-encephalitis panel were evaluated.Patients were divided in two groups based on clinical diagnosis of meningitis.The efficacy of CSF lactate in diagnosing meningitis was evaluated and compared with other tests.RESULTS Seventy-one patients were included and 23 were diagnosed with meningitis.The mean values of CSF total leucocyte count(TLC),proteins and lactates were significantly higher in meningitis group.There was a significant correlation of CSF lactate levels with CSF cultures and meningo-encephalitis panel.CSF lactate(>2.72 mmol/L)showed good accuracy in diagnosing meningitis with an area under the curve of 0.81(95% confidence interval:0.69-0.93),sensitivity of 82.6%,and specificity 72.9%.These values were comparable to those of CSF TLC and protein.Twelve patients with bacterial meningitis had significantly higher CSF lactate(8.9±4.7 mmol/L)than those with non-bacterial meningitis(4.2±3.8 mmol/L),P=0.006.CONCLUSION CSF lactate may be used to aid in our diagnosis of meningitis in ICU patients.CSF lactate(>2.72 mmol/L)showed good accuracy,sensitivity,and specificity in diagnosing meningitis and may also help to differentiate between bacterial and non-bacterial meningitis.

Determination of Ciprofloxacin Lactate by Sodium Tetraphenylboron Method

This paper describes an effective method for determining ciprofloxacin lactate. An excess of sodium tetraphenylboron was added to precipitate ciprofloxacin lactate in HAc-NaAc buffer solution (pH=4.0). After filtering off the precipitate, the excessive sodium tetraphenylboron in the filtrate was titrated with cetyltrimethylammonium bromide standard solution, with bromophenol blue as indicator. The method is simple and rapid, it has been applied to the determination of ciprofloxacin lactate raw material with satisfactory results. The recovery was between 99.66% and 100.2%, the relative error was less than ±0.40%. Experiments showed that the method gave the same results as the approach using nonaqueous titration (ChP).

Characterization of a novel marine microbial esterase and its use to make D-methyl lactate

A novel marine microbial esterase PHE14 was cloned from the genome of Pseudomonas oryzihabit‐ans HUP022 isolated from the deep sea of the western Pacific Ocean. Esterase PHE14 exhibited very good tolerance to most organic solvents, surfactants and metal ions tested, thus making it a good esterase candidate for organic synthesis that requires an organic solvent, surfactants or metal ions. Esterase PHE14 was utilized as a biocatalyst in the asymmetric synthesis of D‐methyl lactate by enzymatic kinetic resolution. D‐methyl lactate is a key chiral chemical. Contrary to some previous reports, the addition of an organic solvent and surfactants in the enzymatic reaction did not have a beneficial effect on the kinetic resolution catalyzed by esterase PHE14. Our study is the first report on the preparation of the enantiomerically enriched product D‐methyl lactate by enzymatic kinetic resolution. The desired enantiomerically enriched product D‐methyl lactate was obtained with a high enantiomeric excess of 99%and yield of 88.7%after process optimization. The deep sea mi‐crobial esterase PHE14 is a green biocatalyst with very good potential in asymmetric synthesis in industry and can replace the traditional organic synthesis that causes pollution to the environment.

Amperometric Enzyme Biosensor for the Determination of High Concentration Lactate in Whole Blood of Athletes

<正>Amperometric biosensor applied to the determination of high concentration lactate in serum and whole blood was described.The biosensor was constructed by gold electrode modified with nanoplatinum particles.Lactate oxidase (E.C.1.1.3.2) was immobilized at platinized activated gold electrode which was used for the determination of high concentration lactate at low potential (+0.2 V).The linear calibration graphs were obtained from 1 to 21 mmol·L~ (-1) lactate in serum and from 0.9 to 13.2 mmol.L~ (-1) lactate in whole blood.The correlation coefficients were 0.99 and 0.97,respectively at a steady-state response time of 50 s.

Combined APACH Ⅱ score and arterial blood lactate clearance rate to predict the prognosis of ARDS patients

Objective:To explore the easily applicable indicators of practical value to evaluate the prognosis of acute respiratory distress syndrome（ARDS）.Methods:Blood and biochemical tests and bloodgas analyses were performed upon entry into the ICUs,12 h,24 h,48 h and 72 h after that in 72 ARDS patients（who were admitted to the ICUs of our hospital from January 2000 to December 2009）.Then APACHEⅡscores were achieved by combining relevant physiological parameters and laboratory results.Results:There was a statistical difference between the death group and survival group at different time points upon entering the ICUs in terms of APACHEⅡscore, alveolar-arterial oxygen difference and arterial blood lactate clearance rate.PaO2/FiO2 values were recorded to be statistically different between the death group and survival group 24 h,48 h and 72 h,respectively after entry into the ICUs.In addition,registered linear regression existed between APACHEⅡscore,alveolar-arterial oxygen difference or PaO2/FiO2 value and time. APACHEⅡscore 24 h and 72 h after entering ICUs predicted mortality with an area under the ROC curve（AUC） standing respectively at 0.919 and 0.9SS.Arterial blood lactate clearance rate 12 h, 24 h,48 h and 72 h after entering ICUs predicted mortality with an area under the ROC curve （AUC） at 0.918,0.918,0.909 and 0.991,respectively.Conclusions:APACHEⅡscore applied in combination with arterial blood lactate clearance rate is of clinical significance in assessing the prognosis of ARDS patients.

Fluid resuscitation in acute pancreatitis: Normal saline or lactated Ringer's solution?

AIM: To investigate whether administration of Ringer's solution(RL) could have an impact on the outcome of acute pancreatitis(AP).METHODS: We conducted a retrospective study on 103 patients [68 men and 35 women,mean age 51.2 years(range,19-92 years)] hospitalized between 2011 and 2012. All patients admitted to the Department of Gastroenterology of the Central Clinical Hospital of the Ministry of Interior(Poland) with a diagnosis of AP who had disease onset within 48 h of presentation were included in this study. Based on the presence of persistent organ failure(longer than 48 h) as a criterion for the diagnosis of severe AP(SAP) and the presence of local complications [diagnosis of moderately severe AP(MSAP)],patients were classified into 3 groups: mild AP(MAP),MSAP and SAP. Data were compared between the groups in terms of severity(using the revised Atlanta criteria) and outcome. Patients were stratified into 2 groups based on the type of fluid resuscitation: the 1-RL group who underwent standard fluid resuscitation with a RL 1000 m L solution or the 2-NS group who underwent standard fluid resuscitation with 1000 m L normal saline(NS). All patients from both groups received an additional 5% glucose solution(1000-1500 m L) and a multi-electrolyte solution(500-1000 m L).RESULTS: We observed 64(62.1%) patients with MAP,26(25.24%) patients with MSAP and 13(12.62%) patients with SAP. No significant difference in the distribution of AP severity between the two groups was found. In the 1-RL group,we identified 22(55.5%) MAP,10(25.5%) MSAP and 8(20.0%) SAP patients,compared with 42(66.7%) MAP,16(24.4%) MSAP and 5(7.9%) SAP cases in the 2-NS group(P = 0.187). The volumes of fluid administered during the initial 72-h period of hospitalization were similar among the patients from both the 1-RL and 2-NS groups(mean 3400 m L vs 3000 m L,respectively). No significant differences between the 1-RL and 2-NS groups were found in confirmed pancreatic necrosis [10 patients(25%) vs 12 patients(19%),respectively,P = 0.637]. There were no statistically significant differences between the 1-RL and 2-NS groups in the percentage of patients who required enteral nutrition(23 patients vs 17 patients,respectively,P = 0.534). Logistic regression analysis confirmed these findings(OR = 1.344,95%CI: 0.595-3.035,P = 0.477). There were no significant differences between the 1-RL and 2-NS groups in mortality and the duration of hospital stay(median of 9 d for both groups,P = 0.776).CONCLUSION: Our study failed to find any evidence that the administration of RL in the first days of AP leads to improved clinical outcomes.

Plasma D(-)-lactate as a new marker for diagnosis of acute intestinal injury following ischemia-reperfusion

IM To observe the kinetics of D()lactate alteration in both portal and systemic circulations, and its relationship with intestinal injury in rats subjected to acute intestinal ischemiareperfusion.METHODS Anesthetized rats underwent 75min superior mesenteric artery occlusion followed by 6hour reperfusion. Plasma D()lactate levels were measured by an enzymatic spectrophotometric assay.RESULTS Intestinal ischemia for 75 min resulted in a significant elevation of D()lactate levels in portal vein as compared with the baseline values (P<005). Plasma D()lactate levels had a tendency to further increase after reperfusion up to 6 hours. Similar alterations in D()lactate were also found in systemic circulation, there were no significant differences between the portal and systemic circulations at any time point. Moreover, the macropathological evaluation scores were significantly correlated to the portal D()lactate levels in animals at various time points (r=0415, P<001). In addition,there was a remarkable rise of endotoxin concentration within the portal vein at the end of 75min ischemia (P<005), reaching a peak at 2 hours postreperfusion.CONCLUSION Acute intestinal ischemia is associated with failure of mucosal barrier resulting in increased plasma D()lactate levels in both portal and systemic blood. The subsequent reperfusion might further increase D()lactate levels, which are correlated to the macropathological alterations. Plasma D()lactate may be a useful marker of intestinal injury following both ischemia and reperfusion insults.

Clinical significance of lactate in acute cardiac patients

Lactate, as a metabolite of easy and quick assessment, has been studied over time in critically ill patients in order to evaluate its prognostic ability. The present review is focused on the prognostic role of lactate levels in acute cardiac patients(that is with acute coronary syndrome, cardiogenic shock, cardiac arrest, non including post cardiac surgery patients). In patients with STelevation myocardial infarction treated with mechanical revascularization, hyperlactatemia identified a subset of patients at higher risk for early death and in-hospital complications, being strictly related mainly to hemodynamic derangement. The prognostic impact of hyperlactatemia on mortality has been documented in patients with cardiogenic shock and in those with cardiac arrest even if there is no cut-off value of lactate to be associated with worse outcome or to guide resuscitation or hemodynamic management. Therapeutic hypothermia seems to affect per se lactate values which have been shown to progressively decrease during hypothermia. The mechanism(s) accounting for lactate levels during hypothemia seem to be multiple ranging from the metabolic effects of reduced temperatures to the hemodynamic effects of hypothermia(i.e., reduced need of vasopressor agents). Serial lactate measurements over time, or lactate clearance, have been reported to be clinically more reliable than lactate absolute value also in acute cardiac patients. Despite differences in study design, timing of lactate measurements and type of acute cardiac conditions(i.e., cardiogenic shock, cardiac arrest, refractory cardiac arrest), available evidence strongly suggests that higher lactate levels can be observed on admission in non-survivors and that higher lactate clearance is associated with better outcome.

Effectiveness and Safety of Double-balloon Catheter versus Intra-amniotic Injection of Ethacridine Lactate for Termination of Second Trimester Pregnancy in Patients with Liver Dysfunction

Severe liver dysfunction in pregnancy（SLDP） is rare but serious complications with high mortality rate. This study compared the effectiveness and safety of double-balloon catheter versus intra-amniotic injection of ethacridine lactate for the termination of second trimester pregnancy in patients with SLD. A total of 55 patients with indications of labor induction were enrolled and analyzed by retrospective control analysis method. Twenty-three cases adopted Cook double balloon dilation as Cook group, and 32 cases received intra-amniotic injection of ethacridine lactate as EL group. The primary outcome was evaluated by successful abortion rate and the difference in the induction-to-abortion interval. Secondary outcomes included liver function recovery and the frequency of adverse events. Both Cook and EL regimens were effective, with successful abortion rate of 87.0% and 93.8%, respectively（P=0.639）. The induction-to-delivery interval was similar between Cook group and EL group（38.1±21.5 vs. 41.3±17.4, P=0.543）. The liver disease status was more severe in Cook group than in EL group, but it did not show any significant difference after pregnancy termination between the two groups and the improvement rate also did not show any significant difference. Both treatments were safe and there was no significant difference in bleeding and cervical laceration adverse events between the two groups. Our study firstly compared double-balloon catheter and ethacridine lactate for the induction of labor in women with SLD during second trimester pregnancy.

Lactate Promotes Cancer Stem-like Property of Oral Sequamous Cell Carcinoma

Accumulation of lactate in tumor has been linked to poor prognosis of oral squamous cell carcinoma (OSCC), but the underlying mechanism remained largely uncertain. Previous studies have suggested that presence of cancer stem cells (CSCs) closely correlated with cellular malignancy of OSCC. Here, using 3D organoid culture model, we investigated whether lactate promoted CSCs phenotype in primary OSCC cells. We generated organoids using fresh OSCC specimens and verified that organoids recapitulated histopathology and cellular heterogeneity of parental tumor;Organoids were then transfected with a Wnt reporter to visualize Wnt activity. The sphere forming assay demonstrated that high Wnt activity functionally designated CSCs population in OSCC cells. Further investigations indicated that lactate treatment promoted Wnt activity and increased the expression of CSCs (i.e. CD133^+ cells) in organoids. Moreover, silencing monocarboxylate transporter 1 (MCT1), the prominent path for lactate uptake in human tumor with siRNA significantly impaired organoid forming capacity of OSCC cells. Together, our study demonstrated that lactate can promote CSCs phenotype of OSCC,and MCT1 may be a therapeutic target against OSCC growth.

KNaY-zeolite catalyzed dehydration of methyl lactate

A promising catalyst, KNaY was prepared by an ion exchange method with aqueous potassium chloride solution, Compared with NaY, KNaY was an effective catalyst for the dehydration of methyl lactate to methyl acrylate. Under the optimized conditions, an improved yield of 37.9 mol% was achieved.

Influence of selenium induced oxidative stress on spermatogenesis and lactate dehydrogenase-X in mice testis

Aim: To evaluate the effect of oxidative stress on the spermatogenesis and lactate dehydrogenase-X (LDH-X) activity in mouse testis. Methods: For creating different levels of oxidative stress in mice, three selenium (Se) level diets were fed in separate groups for 8 weeks. Group 1 animals were fed yeast-based Se-deficient (0.02 ppm) diet. Group 2 and Group 3 animals were fed with the same diet supplemented with 0.2 ppm and 1 ppm Se as sodium selenite, respectively. After 8 weeks, biochemical and histopathological observations of the testis were carried out. LDH-X levels in the testis were analyzed by western immunoblot and ELISA. Results: A significant decrease in testis Se level was observed in Group 1 animals, whereas it was enhanced in Group 3 as compared to Group 2. The glutathione peroxidase (GSH-Px) activity was significantly reduced in both the liver and testis in Group 1, but not in Group 2 and 3. A significant increase in the testis glutathione-S-transferase (GST) activity was observed in Group 1, whereas no significant change was seen in Groups 2 and 3. Histological analysis of testis revealed a normal structure in Group 2. A significant decrease in the germ cell population in Group 1 was observed as compared to Group 2 with the spermatids and mature sperm affected the most. Decrease in the lumen size was also observed. In the Se-excess group (Group 3), displacement of germ cell population was observed. Further, a decrease in the LDH-X level in testis was observed in Group 1. Conclusion: Excessive oxidative stress in the Se deficient group, as indicated by changes in the GSH-Px/GST activity, affects the spermatogenic process with a reduction in mature sperm and in turn the LDH-X level.

Changes of c-fos, Malondialdehyde and Lactate in Brain Tissue after Global Cerebral Ischemia under Different Brain Temperatures

Summary： Under global cerebral ischemia, the effect of different brain temperature on cerebral ischemic injury was studied. Male Sprague-Dawley rats were divided into normothermic （37-38℃） ischemia, mild hypothermic （31 32℃） ischemia, hyperthermic （41-42℃） ischemia and sham-operated groups. Global cerebral ischemia was established using the Pulsinelli four-vessel occlusion model and brain temperature was maintained at defined level for 60 min after 20omin ischemia. The expression of c-fos protein and the levels of malondialdehyde （MDA） and lactate in brain regions were detected by immunochemistry and spectrophotometrical methods, respectively. C-fos positive neurons were found in the hippocampus and cerebral cortex after cerebral ischemia reperfusion. Mild hypothermia increased the expression of c-fos protein in both areas, whereas hyperthermia decreased the expression of c-los protein in the hippocampus at 24 h reperfusion, and the cerebral cortex at 48 h reperfusion when compared to normothermic conditions. In normothermic, mild hypothermic and hyperthermic ischemia groups, the levels of MDA and lactate in brain tissue were increased at 24, 48 and 72 h reperfusion fol- lowing 20-min ischemia as compared with the sham-operated group （P〈0.01）. The levels of MDA and lactate in mild hypothermic group were significantly lower than those in normothermic group （P〈0.01）. It is suggested that brain temperature influences the translation of the immunoreactive protein product of c-fos after global cerebral ischemia, and MDA and lactate are also affected by hypothermia and hyperthermia.

Identification and bioinformatics analysis of lactate dehydrogenase genes from Echinococcus granulosus

Objective:To identify full length cDNA sequence of lactate dehydrogenase(LDH) from adult Echinococcus granulosus(E.granulosus) and to predict the structure and function of its encoding protein using bioinformatics methods.Methods:With the help of NCBI,EMBI, Expasy and other online sites,the open reading frame(ORF),conserved domain,physical and chemical parameters,signal peptide,epitope,topological structures of the protein sequences were predicted and a homology tertiary structure model was created:Vector NT1 software was used for sequence alignment,phylogenetic tree construction and tertiary structure prediction. Results:The target sequence was 1 233 bp length with a 996 bp biggest ORF encoding 331 amino acids protein with typical L-LDH conserved domain.It was confirmed as full length cDNA of LDH from E.granulosus and named as EgLDH(GenBank accession number:HM748917).The predicted molecular weight and isoelectric point of the deduced protein were 3 5516.2Da and 6.32 respectively.Compared with LDHs from Taenia solium,Taenia saginata asiatica,Spirometra erinaceieuropaei.Schistosoma japonicum,Clonorchis sinensis and human,it showed similarity of 86% ,85% ,55% ,58% ,58% and 53% ,respectively.EgLDH contained 3 putative transmembrane regions and 4 major epitopes(54aa-59aa.81aa-87aa,97aa-102aa,307aa-313aa),the latter were significant different from the corresponding regions of human LDH.In addition,some NAD and substrate binding sites located on epitopes 54aa-59aa and 97aa-102aa,respectively.Tertiary structure prediction showed that 3 key catalytic residues 105R,165D and 192H forming a catalytic center near the epitope 97aa-102aa,most NAD and substrate binding sites located around the center.Conclusions:The full length cDNA sequences of EgLDH were identified.It encoded a putative transmembrane protein which might be an ideal target molecule for vaccine and drugs.