Lactate Dehydrogenase Activity Research Articles

Neuroprotective Effect of Sterculia setigera Leaves Hydroethanolic Extract.

Plants are a valuable source of information for pharmacological research and new drug discovery. The present study aimed to evaluate the neuroprotective potential of the leaves of the medicinal plant Sterculia setigera. In vitro, the effect of Sterculia setigera leaves dry hydroethanolic extract (SSE) was tested on cultured cerebellar granule neurons (CGN) survival when exposed to hydrogen peroxide (H2O2) or 6-hydroxydopamine (6-OHDA), using the viability probe fluorescein diacetate (FDA), a lactate dehydrogenase (LDH) activity assay, an immunocytochemical staining against Gap 43, and the quantification of the expression of genes involved in apoptosis, necrosis, or oxidative stress. In vivo, the effect of intraperitoneal (ip) injection of SSE was assessed on the developing brain of 8-day-old Wistar rats exposed to ethanol neurotoxicity by measuring caspase-3 activity on cerebellum homogenates, the expression of some genes in tissue extracts, the thickness of cerebellar cortical layers and motor coordination. In vitro, SSE protected CGN against H2O2 and 6-OHDA-induced cell death at a dose of 10µg/mL, inhibited the expression of genes Casp3 and Bad, and upregulated the expression of Cat and Gpx7. In vivo, SSE significantly blocked the deleterious effect of ethanol by reducing the activity of caspase-3, inhibiting the expression of Bax and Tp53, preventing the reduction of the thickness of the internal granule cell layer of the cerebellar cortex, and restoring motor functions. Sterculia setigera exerts neuroactive functions as claimed by traditional medicine and should be a good candidate for the development of a neuroprotective treatment against neurodegenerative diseases.

Egr1 promotes Nlrc4-dependent neuronal pyroptosis through phlda1 in an in-vitro model of intracerebral hemorrhage.

Intracerebral hemorrhage (ICH) is a fatal brain injury, but the current treatments for it are inadequate to reduce the severity of secondary brain injury. Our study aims to explore the molecular mechanism of Egr1 and Phlda1 in regulating hemin-induced neuronal pyroptosis, and hope to provide novel therapeutic targets for ICH treatment. Mouse hippocampal neuron cells treated with hemin were used to simulate an in-vitro ICH model. Using qRT-PCR and western blot to evaluate mRNA and protein concentrations. MTT assay was utilized to assess cell viability. LDH levels were determined by lactate Dehydrogenase Activity Assay Kit. IL-1β and IL-18 levels were examined by ELISA. The interaction of Egr1 and Phlda1 promoter was evaluated using chromatin immunoprecipitation and dual-luciferase reporter assays. Egr1 and Phlda1 were both upregulated in HT22 cells following hemin treatment. Hemin treatment caused a significant reduction in HT22 cell viability, an increase in Nlrc4 and HT22 cell pyroptosis, and heightened inflammation. However, knocking down Egr1 neutralized hemin-induced effects on HT22 cells. Egr1 bound to the promoter of Phlda1 and transcriptionally activated Phlda1. Silencing Phlda1 significantly reduced Nlrc4-dependent neuronal pyroptosis. Conversely, overexpressing Phlda1 mitigated the inhibitory effects of Egr1 knockdown on Nlrc4 and neuronal pyroptosis during ICH. Egr1 enhanced neuronal pyroptosis mediated by Nlrc4 under ICH via transcriptionally activating Phlda1.

Impact of chronic fluoxetine exposure on zebrafish: From fatty acid profile to behavior

The consumption of antidepressants, such as fluoxetine, has increased over the years and, as a result, they are increasingly found in aquatic systems. Given the increasing use of zebrafish as an animal model in toxicological studies, this work proposed to evaluate the effects of chronic exposure, for 21 days, to fluoxetine at environmentally relevant concentrations (1, 10, 100, and 1000 ng/L). The behavioral tests performed did not reveal significant effects of fluoxetine. However, oxidative stress and changes in energy metabolism were detected after exposure to the highest concentrations of fluoxetine tested, namely a decrease in glutathione S-transferase (GST) activity (decrease of ca. 31%), increase in catalase (CAT) activity (increase of ca. 71%), and decrease in lactate dehydrogenase (LDH) activity (decrease of ca. 53%). Analysis of the fatty acid profile (FA) revealed a decrease in the omega-3 FA, docosahexaenoic acid (DHA), C22:6 (decrease in relative abundance between 6% and 8% for both the head and body), an increase in omega-6 FA, linoleic acid (LA), C18:2, (increased relative abundance between 8% and 11% in the head and between 5% and 9% in the body), which may suggest changes in the inflammatory state of these organisms. The integrated analysis adopted proved to be useful in detecting subindividual effects of fluoxetine and modes of action in fish.

Effects of 2,4-dichlorophenol on non–specific immunity, histopathological lesions, and redox balance in African Catfish, clarias gariepinus (Burchell, 1822)

ABSTRACT The toxic effects of 2, 4-dichlorophenol (2, 4-DCP) on aquatic organisms are well-established; however, the details regarding the mechanisms underlying the toxicity, especially immunotoxicity are poorly understood. Consequently, the aim of this study was to investigate the histopathologic, oxidative stress and immunotoxic effects attributed to exposure to sublethal concentrations of 2,4-DCP in the African catfish, Clarias gariepinus. Juvenile C. gariepinus were exposed to 0.4, 0.8, or 1.6 mg/L 2, 4-DCP for 28 days after which blood and head kidney were extracted for the determination of various nonspecific innate immune parameters while the liver was excised for histopathology examination and measurement of oxidative stress biomarkers. Control fish were maintained in water spiked 10 µL/L ethanol, representing the solvent control. A significant increase was noted in the activities of lactate dehydrogenase and superoxide dismutase as well as in levels of lipid peroxidation and DNA fragmentation in a dose-dependent manner, with higher adverse effects observed at the highest concentration tested (1.6 mg/L). The total white blood cells (WBC) count was significantly elevated in fish exposed to 2,4-DCP compared to control. Myeloperoxidase content was decreased significantly in fish exposed to 2,4-DCP especially at the highest concentration (1.6 mg/L) compared to controls. The respiratory burst activity did not differ markedly amongst groups. Histopathological lesions noted included edema, leucocyte infiltration, and depletion of hemopoietic tissue in the head kidney of exposed fish. There was significant upregulation in the mRNA expression of tumor necrosis factor (TNF-α) and heat shock protein 70 (HSP 70) but downregulation of major histocompatibility complex 2 (MHC 2) in exposed fish. Data demonstrated that exposure to 2,4-DCP resulted in histopathological lesions, oxidative stress, and compromised immune system in C. gariepinus.

Transcriptional regulation of lactate dehydrogenase activity in rat kidney cells in diabetic nephropathy

Aim. To study the features of transcriptional regulation of the activity and isoenzyme composition of lactate dehydrogenase in the kidneys of Rattus norvegicus L. in diabetic nephropathy.Materials and methods. The study included 20 male laboratory rats (Rattus norvegicus L.) divided into two equal groups: “Norm” – intact rats injected with 0.9% NaCl intraperitoneally and “Diabetes” – animals with alloxaninduced diabetes (DM1 model). The activity, subcellular localization, and mobility of lactate dehydrogenase (LDH, EC 1.1.1.27) isoenzymes were studied using spectrophotometry and electrophoresis. LDHA and LDHB gene transcripts were analyzed by the polymerase chain reaction.Results. Analysis of the LDH activity showed that this parameter increased by more than 6 times in the animals with diabetic nephropathy compared to the control group. Moreover, the increase in the rate of the LDH activity was a consequence of the enzyme activation in all the studied compartments of the cell and is consistent with the parameter in the homogenate. The increase in the LDH activity in diabetic nephropathy may result from redistribution of the activity rate between the available isoforms and may be associated with an increase in the transcription rate of genes encoding subunits A and B of this enzyme.Conclusion. The increase in the LDH activity is likely associated with the activation of renal gluconeogenesis, the main substrate for which is lactic acid reabsorbed in the renal glomeruli. The revealed increase in the LDH activity in the kidneys of rats with diabetic nephropathy may be associated with adaptation of their metabolism to the pathological state.

Assessment of the biological effect of natural silicon when entering the body of experimental animals with drinking water. Part 1

Introduction. The biological effect of natural silicon (Si) and its hygienic regulation in drinking water still remain subjects of controversy in the scientific literature and in the practice of providing favourable conditions for water use by the population. In this regard, an assessment was made of the effect of natural silicon contained in drinking water in concentrations close to the maximum permissible concentration on the body of laboratory animals.
 Materials and methods. Drinking waters containing natural Si at MPC levels in water were studied, their effect was assessed in a three-month experiment on 80 white outbred male rats. Observations were made of the general condition, appearance of the animals, body weight dynamics, water consumption. 
 The morphological composition of whole blood was studied. Biochemical indices of the condition of internal organs, including the liver, were determined 
 in serum samples (the ALT and AST activity, the level of total protein and albumin), pancreas (α-amylase activity), kidneys (creatinine content), as well as lactate dehydrogenase activity as a nonspecific indicator of tissue damage.
 Results. In animals received 17±3.4 mg/L silicon with drinking water at a hardness of 2.25±0.47 mg-eq/L, a significant decrease in ALT activity was found on the 30th and 90th days of the experiment, AST – on 90th day, increase in the content of total protein and albumin in the serum on the 30th day of the experiment. Drinking water with silicon concentrations of 20.5±4.1 mg/L and hardness 3.55±0.76 mg-eq/L decreased ALT activity and serum creatinine concentration on the 30th day and increased amylase activity on the 90th day of the experiment. The animals had the highest water consumption and intake of silicon from drinking water over the first month of the experiment.
 Limitations. Limitations of the study are related to the short duration of observation and the small number of points for determining biochemical parameters over time.
 Conclusion. Consumption of drinking water containing natural silicon for 90 days led to changes in biochemical indices, largely indicating the positive effect of the element in concentrations of 17±3.4 mg/L and 20.5±4.1 mg/L on the body of laboratory animals.

Reversal of Valproate-Induced Major Salivary Gland Changes By Moringa Oleifera Extract in Rats.

This study aimed to explore the potential protective impacts of Moringa oleifera extract on major alteration in salivary glands of rats exposed to sodium valproate (VA). Groups were defined as control, control+moringa extract, sodium valproate, and sodium valproate+moringa extract. Antioxidant and oxidant status, activities of digestive and metabolic enzymes were examined. VA treatment led to various biochemical changes in the salivary glands, including decreased levels of antioxidants like glutathione, glutathione-S-transferase, and superoxide dismutase (except for sublingual superoxide dismutase). Conversely, a decrease in alpha-amylase, alkaline and acid phosphatase, lactate dehydrogenase, protease, and maltase activities were observed. The study also demonstrated that VA induces oxidative stress, increases lipid peroxidation, sialic acid, and nitric oxide levels in the salivary glands. Total oxidant capacity was raised in all glands except in the sublingual gland. The electrophoretic patterns of proteins were similar. Moringa oleifera extract exhibited protective properties, reversing these VA-induced biochemical changes due to its antioxidant and therapeutic attributes. This research suggests that moringa extract might serve as an alternative treatment approach for individuals using VA and experiencing salivary gland issues, although further research is necessary to confirm these findings in human subjects.

Disrupting glycolysis and DNA repair in anaplastic thyroid cancer with nucleus-targeting platinum nanoclusters

Cancer cells rely on aerobic glycolysis and DNA repair signals to drive tumor growth and develop drug resistance. Yet, fine-tuning aerobic glycolysis with the assist of nanotechnology, for example, dampening lactate dehydrogenase (LDH) for cancer cell metabolic reprograming remains to be investigated. Here we focus on anaplastic thyroid cancer (ATC) as an extremely malignant cancer with the high expression of LDH, and develop a pH-responsive and nucleus-targeting platinum nanocluster (Pt@TAT/sPEG) to simultaneously targets LDH and exacerbates DNA damage. Pt@TAT/sPEG effectively disrupts LDH activity, reducing lactate production and ATP levels, and meanwhile induces ROS production, DNA damage, and apoptosis in ATC tumor cells. We found Pt@TAT/sPEG also blocks nucleotide excision repair pathway and achieves effective tumor cell killing. In an orthotopic ATC xenograft model, Pt@TAT/sPEG demonstrates superior tumor growth suppression compared to Pt@sPEG and cisplatin. This nanostrategy offers a feasible approach to simultaneously inhibit glycolysis and DNA repair for metabolic reprogramming and enhanced tumor chemotherapy.

Diffuse large B-cell lymphoma with DNA copy number changes in a Japanese black calf

A 2-month-old Japanese Black calf exhibited mandibular and superficial cervical lymph node swelling. Fine needle aspiration cytology of the superficial cervical lymph node revealed large lymphoblast-like cells with mitoses. Hematological examination revealed remarkable lymphocytosis with atypical lymphocytes. Increased activities of serum total lactate dehydrogenase and thymidine kinase were detected. At necropsy, generalized swelling of lymph nodes was observed. Histopathological analysis revealed diffuse proliferation of medium-sized round centroblastic neoplastic cells that were positive for CD20, CD79α, PAX5, and BLA-36, and negative for CD3, CD5, CD10, and CD34. The calf was diagnosed with centroblastic diffuse large B-cell lymphoma (DLBCL) based on these findings. Analysis of DNA copy number variation revealed an increased copy number for the GIMAP family relative to that in healthy cattle. Moreover, decreases in copy numbers of GBP-1, MIR3141, OR5P1E, and PTPRG relative to those in healthy cattle were also observed. Because DNA copy number variation represent a major contribution to the somatic mutation landscapes in human tumors, these findings suggest that DNA copy number changes might have contributed to the onset of DLBCL in the present case.

Epigallocatechin-3-gallate confers protection against myocardial ischemia/reperfusion injury by inhibiting ferroptosis, apoptosis, and autophagy via modulation of 14–3-3η

Previous studies have demonstrated that the underlying mechanisms of myocardial ischemia/reperfusion injury (MIRI) are complex and involve multiple types of regulatory cell death, including ferroptosis, apoptosis, and autophagy. Thus, we aimed to identify the mechanisms underlying MIRI and validate the protective role of epigallocatechin-3-gallate (EGCG) and its related mechanisms in MIRI. An in vivo and in vitro models of MIRI were constructed. The results showed that pretreatment with EGCG could attenuate MIRI, as indicated by increased cell viability, reduced lactate dehydrogenase (LDH) activity and apoptosis, inhibited iron overload, abnormal lipid metabolism, preserved mitochondrial function, decreased infarct size, maintained cardiac function, decreased reactive oxygen species (ROS) level, and reduced TUNEL-positive cells. Additionally, EGCG pretreatment could attenuate ferroptosis, apoptosis, and autophagy induced by MIRI via upregulating 14–3–3η protein levels. Furthermore, the protective effects of EGCG could be abolished with pAd/14–3–3η-shRNA or Compound C11 (a 14–3–3η inhibitor) but not pAd/NC-shRNA. In conclusion, EGCG pretreatment attenuated ferroptosis, apoptosis, and autophagy by mediating 14–3–3η and protected cardiomyocytes against MIRI.

Venomous snakebites in children: a 10 year experience in South China

Introduction Many studies have focused on snakebites in adults, but very few have described snakebites in children. Methods We reviewed the clinical characteristics and outcomes of children with venomous snakebites aged less than 15 years who presented to a regional medical centre in South China from January 2013 to December 2022. Results A total of 69 envenomed patients were analyzed in our study; 42 (60.9 per cent) patients were male, and 59 (85.5 per cent) reported lower limb bites. Most bites (89.8 per cent) occurred between April and October. Twenty-seven patients received first aid management, and 47 required admission to the general ward. Antivenom was administered to 58 patients, glucocorticoids to 43 patients, antibiotics to 48 patients, and tetanus antitoxin to 40 patients. No fatalities were reported. The most common snake identified was Trimeresurus albolabris. Four were classified as dry bites, 15 as mild, 43 as moderate, and seven as severe. The most common local signs were pain and swelling, while the most common systemic effects were haematological complications. Patients with high severity scores had significantly higher lactate dehydrogenase activities, creatine kinase isoenzyme activities, aspartate aminotransferase activities, D-dimer concentrations, prothrombin times and lower fibrinogen concentrations. In a receiver operating characteristic curve analysis of the values with the highest Youden index, the following cut-offs proved significant: lactate dehydrogenase activity > 248.1 U/L, creatine kinase isoenzyme activities > 17.5 U/L, fibrinogen concentration < 1,455 mg/L, D-dimer concentration > 437.0 µg/L, aspartate aminotransferase activity > 26.1 U/L, and prothrombin time > 15.2 seconds. Discussion This study provides insight into the epidemiology, clinical profile, and management of snakebites in children. Data from the present study were compared with those from our previous adult study. Limitations include that 50.7 per cent of our snakebites were attributed to Trimeresurus albolabris. Therefore, the results of our study may not be generalizable to all snakebites. Conclusion The clinical symptoms were more severe in children than in adults in our previous study. Even though there were no fatalities, close monitoring should be performed to detect haematological and other potentially fatal complications promptly.

Changes of peripheral blood α-L-fucosidase activity in patients with rheumatoid arthritis: a cross-sectional study.

Rheumatoid arthritis (RA), a systemic autoimmune disease with approximately 1% prevalent population worldwide, which the etiology is still unclear. RA cannot be completely cured at present, which seriously affects the quality of life of patients. This study is to compare the peripheral blood α-L-fucosidase (AFU) between RA and healthy persons. A cross-sectional study was performed using total of 96 patients with RA served as case group and another 94 age-matched healthy volunteers served as a control group. AFU assay is detected by continuous monitoring method using Toshiba TBA-120FR (Tokyo, Japan) fully automatic biochemical analyzer in Japan, and the reagent is purchased from Zhejiang Quark Biological Company (Zhejiang, China). Statistical analysis was performed using SPSS 24.0 (SPSS, Inc., Chicago, IL, USA). AFU activity in peripheral blood of RA patients were lower than healthy controls. The higher AFU activity, the shorter the course of disease (r=-0.2790, P=0.0065). The activity of lactate dehydrogenase in patients with RA is higher than that of healthy control, but the activity of acetylcholinesterase is lower than that of normal people. Finally, AFU activity was negatively correlated with the activity of lactate dehydrogenase (r=-0.2381, P=0.0208) and positively correlated with the activity of acetylcholinesterase (r=0.2985, P=0.0035). Changes of peripheral blood AFU activity might be associated with progression of disease in RA patients. The changes of AFU activity may lead to disturbances in glucose and lipid metabolism.

A Comparative Study of Vitamin D Level and Lactate Dehydrogenase Activity in Relation to Oxidative Stress in Women with Osteoporosis

Background: Osteoporosis (OP) is a silent disease that affects the microarchitecture of the skeleton bones, leading to a drop in mineral levels and an increase in fracture rates. This condition is more common in women than men, especially postmenopausal women, due to decreased production of estrogen, a hormone that regulates bone formation and bone resorption. Oxidative stress is a known factor in the development of OP, resulting from an imbalance in the production of oxidants and antioxidants. Hip and arm fractures are particularly common in women with OP. Objective: The study aimed to evaluate the activity of Lactate Dehydrogenase (LDH) and oxidative stress (OS) levels in postmenopausal women with osteoporosis and varying levels of vitamin D, and to compare these groups based on the measured parameters. Subjects and Methods: This study was conducted at the Baquba Teaching Hospital in Diyala, Iraq, from October 2022 to January 2023. The study involved 100 women whom were divided into two groups, 50 with normal vitamin D levels and 50 with abnormal vitamin D levels. The malondialdehyde (MDA) level was evaluated using the Satoh-modified approach. Results: According to the statistical analysis conducted with the SPSS program, there was a significant difference (P&lt;0.001) in Vitamin D levels between the groups (OPn. D) and (OPab.D). Additionally, significant increases were observed in LDH activity (P&lt;0.001) and MDA levels (P&lt;0.05) for the group (OPab.D) in comparison to (OPn. D). Conclusion: The current study has indicated that women suffering from osteoporosis (OP) have higher levels of LDH and MDA. Additionally, there is an inverse correlation between vitamin D and these two variables; this correlation suggests that vitamin D may possess antioxidant properties that reduce the effects of oxidative stress (OS) in the body. Therefore, vitamin D may help in reducing LDH levels.

Exploration of Risk Factors of the Onset of Antibiotics-induced Acute Kidney Injury and Its Transfer to Chronic Kidney Disease Using the Medical Information Database

Drug-induced acute kidney injury (AKI) is a serious adverse drug reaction, which results in a significant decline in renal function and is known to progress to chronic kidney disease (CKD). Therefore, appropriate drug therapy is important to avoid the risk of drug-induced AKI and CKD, which are serious concerns in clinical practice. In this study, using the medical information database of Hamamatsu University Hospital, we investigated the risk factors that accelerate the onset of drug-induced AKI or its progression to CKD in patients who received aminoglycoside antibiotics (AGs) or glycopeptide antibiotics (GPs), which are strongly associated with drug-induced AKI and CKD. We performed logistic regression analysis using patients' background, laboratory test results, and concomitant drug use, among other such factors as explanatory variables and drug-induced AKI or CKD onset as objective variables to explore the risk factors for drug-induced AKI and CKD. Our results showed that co-administration of amphotericin B, piperacillin-tazobactam and other AGs and GPs, increased serum creatinine (Scr) and chloride concentrations, serum lactate dehydrogenase activity, and decreased serum albumin concentration were risk factors for drug-induced AKI onset. Moreover, a reduced blood urea nitrogen:Scr ratio at drug-induced AKI onset served as a risk factor for CKD. These results suggest that careful monitoring of the aforementioned factors is important to ensure appropriate usage of these drugs in patients treated with AGs and GPs.

Physiological and biochemical response analysis of Styrax tonkinensis seedlings to waterlogging stress

Climate change is increasing flooding in provinces of the south of the Yangtze River, posing challenges for promoting Styrax tonkinensis seedlings in these areas. To understand the physiological reasons for this species' intolerance to waterlogging, we observed biochemical parameters in one-year-old S. tonkinensis seedlings during two seasons. For 4 and 12 days in summer and winter experiments, respectively, we subjected seedlings to a pot-in-pot waterlogging treatment. Control groups were established at 0 h and 0 days. We examined indicators related to root vigor, reactive oxygen species (ROS), antioxidant enzymes, fermentative pathways, and more. The results displayed that decreased abscisic acid accumulation in roots inhibited water transport. Increased dehydrogenase and lactate dehydrogenase activity in roots promoted alcohol and lactate fermentation, causing toxic damage and reduced root vigor, impeding water absorption. In leaves, high ROS levels led to lipid peroxidation, exacerbating water loss from continuous transpiration. The high relative electric conductivity and low leaf relative water content indicated water loss, causing leaf wilting and shriveling. Conversely, winter seedlings, devoid of leaves, significantly reduced transpiration, and dormancy delayed root fermentation. With less ROS damage in roots, winter seedlings exhibited greater waterlogging tolerance. In summary, excessive water loss from leaves and inhibited vertical water transport contributed to low summer survival rates, while winter leafless dormancy and reduced ROS damage enhanced tolerance. Our findings provide insights for enhancing waterlogging resistance in S. tonkinensis amidst climate change challenges.

Some Acute Phase Proteins and Biochemistry Parameters of Female Dogs Affected with Pyometra

Some Acute Phase Proteins and Biochemistry Parameters of Female Dogs Affected with Pyometra

Effects of Citrobacter freundii on sturgeon: Insights from skin mucosal immunology and microbiota

Skin mucus analysis has recently been used as a non-invasive method to evaluate for fish welfare. The present research study was conducted to examine the skin mucosal immunity and skin microbiota profiles of sturgeons infected with Citrobacter freundii. Our histology results showed that the thickness of the epidermal layer of skin remained thinner, and the number of mucous cells was significantly decreased in sturgeons after infection (p < 0.05). Total protein, alanine aminotransferase, aspartate aminotransferase, superoxide dismutase, and creatine kinase levels in the mucus showed biphasic pattern (decrease and then increase). Lactate dehydrogenase, lysozyme, and acid phosphatase activities in the mucus showed an increasing trend after infection. Furthermore, 16S rRNA sequencing also revealed that C. freundii infection also affected the diversity and community structure of the skin mucus microbiota. An increase in microbial diversity (p > 0.05) and a decrease in microbial abundance (p < 0.05) after infection were noted. The predominant bacterial phyla in the skin mucus were Proteobacteria, Fusobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. Specifically, the relative abundance of Fusobacteria increased after infection. The predominant bacterial genera in the skin mucus were Cetobacterium, Pelomonas, Bradyrhizobium, Flavobacterium, and Pseudomonas. The relative abundance of Cetobacterium, Pseudomonas, and Flavobacterium increased after infection. Our current research findings will provide new insights into the theoretical basis for future research studies exploring the mechanism of sturgeon infection with C. freundii.

Resveratrol protects cardiomyocytes against ischemia/reperfusion-induced ferroptosis via inhibition of the VDAC1/GPX4 pathway

The present study aimed to explore how resveratrol (Res) confers myocardial protection by attenuating ferroptosis. In vivo and in vitro myocardial ischemia/reperfusion injury (MIRI) models were established, with or without Res pretreatment. The results showed that Res pretreatment effectively attenuated MIRI, as evidenced by increased cell viability, reduced lactate dehydrogenase activity, decreased infarct size, and maintained cardiac function. Moreover, Res pretreatment inhibited MIRI-induced ferroptosis, as shown by improved mitochondrial integrity, increased glutathione level, decreased prostaglandin-endoperoxide synthase 2 level, inhibited iron overload, and abnormal lipid peroxidation. Of note, Res pretreatment decreased or increased voltage-dependent anion channel 1/glutathione peroxidase 4 (VDAC1/GPX4) expression, which was increased or decreased via anoxia/reoxygenation (A/R) treatment, respectively. However, the overexpression of VDAC1 via pAd/VDAC1 and knockdown of GPX4 through Si-GPX4 reversed the protective effect of Res in A/R-induced H9c2 cells, whereas the inhibition of GPX4 with RSL3 abolished the protective effect of Res on mice treated with ischemia/reperfusion.Interestingly, knockdown of VDAC1 by Si-VDAC1 promoted the protective effect of Res on A/R-induced H9c2 cells and the regulation of GPX4. Finally, the direct interaction between VDAC1 and GPX4 was determined using co-immunoprecipitation. In conclusion, Res pretreatment could protect the myocardium against MIRI-induced ferroptosis via the VDAC1/GPX4 signaling pathway.

Knockdown of lncRNA NEAT1 suppresses streptococcus pneumoniae-induced ferroptosis in alveolar epithelial cells by regulating the Nrf2-GPX4 pathway

ObjectivesStreptococcus pneumoniae (SP) is a major cause of community-acquired pneumonia. Ferroptosis pitches in pneumonia. Long noncoding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) regulates ferroptosis in various cells. Therefore, this study probed the mechanism of lncRNA NEAT1 on SP-induced ferroptosis in AECs. MethodsSerum lncRNA NEAT1 level in 36 streptococcus pneumonia patients were retrospectively detected, with its correlations with inflammatory factor (TNF-α/IL-1β/IL-6) levels analyzed. Human pulmonary alveolar epithelial cells (HPAEpiC) were transfected with sh-NEAT1 and induced by SP. Cell viability was evaluated by CCK-8. Lactate dehydrogenase (LDH) activity was assessed. Iron content, and levels of TNF-α/IL-1β/IL-6/IL-10/lncRNA NEAT1/lipid peroxidation products [malondialdehyde (MDA)/glutathione (GSH)/reactive oxygen species/(ROS)]/ferroptosis-related proteins [Cyclooxgenase 2 (COX2)/recombinant solute carrier family 7 member 11 (SLC7A11)/total nuclear factor erythroid 2-related factor 2 (Nrf2)/cytoplasmic Nrf2 (C-Nrf2)/nuclear Nrf2 (N-Nrf2)/GPX4)] were determined by kit/ELISA/RT-qPCR/kits/Western blot. Nrf2 nuclear translocation was detected by immunofluorescence assay. On top of lncRNA NEAT1 knockdown, SP-induced HPAEpiC were treated with ML385. ResultsSerum lncRNA NEAT1 level was elevated in streptococcus pneumonia patients, and were positively interrelated with TNF-α/IL-1β/IL-6 levels. SP promoted cell HPAEpiC injury and inflammatory response, and up-regulated lncRNA NEAT1 level. LncRNA NEAT1 knockdown suppressed HPAEpiC injury/inflammatory response (reduced LDH activity and TNF-α/IL-1β/IL-6 levels, elevated IL-10) and suppressed ferroptosis (decreased iron/MDA/ROS contents and COX2 level, increased GSH/SLC7A11), facilitated Nrf2 nuclear translocation, and up-regulated GPX4. Nrf2-GPX4 pathway inhibition annulled NEAT1 knockdown-mediated improvement on SP-induced HPAEpiC ferroptosis/injury/inflammatory response. ConclusionsLncRNA NEAT1 knockdown suppressed SP-induced HPAEpiC ferroptosis by activating Nrf2-GPX4 pathway, thereby alleviating cell injury and inflammatory response.

Zinc alleviates thermal stress-induced damage to the integrity and barrier function of cultured chicken embryonic primary jejunal epithelial cells via the MAPK and PI3K/AKT/mTOR signaling pathways

Zinc (Zn) could alleviate the adverse effect of high temperature (HT) on intestinal integrity and barrier function of broilers, but the underlying mechanisms remain unclear. We aimed to investigate the possible protective mechanisms of Zn on primary cultured broiler jejunal epithelial cells exposed to thermal stress (TS). In Exp.1, jejunal epithelial cells were exposed to 40℃ (normal temperature, NT) and 44℃ (HT) for 1, 2, 4, 6, or 8 h. Cells incubated for 8 h had the lowest transepithelial resistance (TEER) and the highest phenol red permeability under HT. In Exp.2, the cells were preincubated with different Zn sources (Zn sulfate as iZn and Zn proteinate with the moderate chelation strength as oZn) and Zn supplemental levels (50 and 100 µmol/L) under NT for 24 h, and then continuously incubated under HT for another 8 h. TS increased phenol red permeability, lactate dehydrogenase (LDH) activity and p-PKC/PKC level, and decreased TEER, cell proliferation, mRNA levels of claudin-1, occludin, zona occludens-1 (ZO-1), PI3K, AKT and mTOR, protein levels of claudin-1, ZO-1 and junctional adhesion molecule-A (JAM-A), and the levels of p-ERK/ERK, p-PI3K/PI3K and p-AKT/AKT. Under HT, oZn was more effective than iZn in increasing TEER, occludin, ZO-1, PI3K, and AKT mRNA levels, ZO-1 protein level, and p-AKT/AKT level; supplementation with 50 μmol Zn/L was more effective than 100 μmol Zn/L in increasing cell proliferation, JAM-A, PI3K, AKT, and PKC mRNA levels, JAM-A protein level, and the levels of p-ERK/ERK and p-PI3K/PI3K; furthermore, supplementation with 50 μmol Zn/L as oZn had the lowest LDH activity, and the highest ERK, JNK-1, and mTOR mRNA levels. Therefore, supplemental Zn, especially 50 μmol Zn/L as oZn, could alleviate the TS-induced integrity and barrier function damage of broiler jejunal epithelial cells possibly by promoting cell proliferation and tight junction protein expression via the MAPK and PI3K/AKT/mTOR signaling pathways.