Protective Effects Of Ethyl Pyruvate Research Articles

Protective effect of ethyl pyruvate on amikacin-induced ototoxicity in rats.

Amikacin (AMK) is a widely used antibiotic, but its ototoxic side effects limit its use. This study investigated the effects of ethyl pyruvate (EP), known for its antioxidant and anti-inflammatory effects, against AMK ototoxicity. 32 Wistar albino rats (n: 8) were used in this study. To cause ototoxicity, AMK 600 mg/kg/day dose was applied intramuscularly for 14 days. EP was administered via ip at a dose of 50 mg/kg/day for 14 days. The Auditory Brainstem Responses (ABR) and Distortion Product Otoacoustic Emissions (DPOAE) tests were performed on the study's 0, 7, and 14 days. The results have shown that the hearing functions were significantly impaired with the AMK application. A significant improvement was observed in the AMK+EP group. While total oxidant status (TOS), oxidative stress index (OSI), and malondialdehyde (MDA) levels were found to be significantly higher in the AMK group compared to the control group, total antioxidant status (TAS) level was found to be significantly lower. In the AMK+EP group, on the other hand, deterioration in TOS, OSI, and MDA levels detected in the AMK group was not observed. No elevated pro-inflammatory cytokines, such as TNF-α, IL-1β, and IL-6 were present in the EP+AMK group, which were detected in the AMK group. Hearing tests and biochemical results show that ethyl pyruvate has protective effects against amikacin ototoxicity due to its antioxidant and anti-inflammatory effects.

Risperidone and ethyl pyruvate have protective effects against ketamine-induced cognitive impairments in mice.

Ketamine, an N-methyl D-aspartic acid receptor antagonist drug, is reported to produce memory disruptions. The aim of this study was to investigate the protective effects of ethyl pyruvate (EP), a pyruvic acid derivative, and risperidone, an atypical antipsychotic drug, against ketamine-induced cognitive disturbances. A passive-avoidance test, a novel object recognition test, and a modified elevated plus maze test were used to assess memory functions. Hippocampal malondialdehyde (MDA) levels were measured to determine the oxidation levels. Ketamine applications produced memory deficits in all tests and insignificantly increased MDA levels, which were alleviated by risperidone, EP, and combination treatments. Increased oxidative stress and neurotransmission imbalance can be responsible for ketamine-induced memory disruptions. With its antioxidant effects, EP may be helpful to reduce cognitive impairments related to schizophrenia either alone or in combination with antipsychotics.

Effect of Sodium Cyanide-induced Tissue Hypoxia on Reproductive Capability of Male Mice and the Protective Effect of Ethyl Pyruvate.

The present study aimed to assess the effect of tissue hypoxia induced by sodium cyanide (NaCN) on male mice fertility and the protective role of ethyl pyruvate (EP). A number of 30 adult mice were assigned to three groups: 1) a control group, 2) a treatment group treated with 2 mg/kg of NaCN, and 3) a treatment group treated with 2 mg/kg of NaCN, along with 40 mg/kg EP (NaCN+EP). After 35 days, animals were anesthetized and serum, sperm, and tissue samples were taken. The results demonstrated a significant decrease in sperm quality, reproduction potency, and anti-oxidant potential, as well as an increase in lipid peroxidation in the NaCN group (p <0.05). Moreover, the use of EP effectively restrained the disastrous effects of tissue hypoxia. It can be concluded that EP can moderate the complications resulting from tissue-hypoxia that is related to testes parameters.

Protective effect of ethyl pyruvate on gut barrier function through regulations of ROS-related NETs formation during sepsis

BackgroundSepsis impairs the function of the intestinal barrier through neutrophil extracellular traps (NETs). Reactive oxygen species (ROS)-induced activation of mitogen-activated protein kinase (MAPK) is involved in NET formation. Ethyl pyruvate (EP), a potent and effective ROS scavenger, ameliorates sepsis-associated intestinal barrier dysfunction, but the detailed mechanism is unknown. The current study aimed to explore the eff ;ects of EP on sepsis-induced intestinal barrier dysfunction and whether ROS and NETs were involved. MethodsA sepsis model was induced in mice by intraperitoneal injection of LPS (10 mg/kg). The mice were divided into 4 groups: (1) sham group; (2) LPS group; (3) DNase-1 + LPS group; and (4) EP + LPS group. EP or DNase-1 was intraperitoneally injected after the LPS model was established. After 24 h, the small intestine and blood were collected for analysis. Human neutrophils were harvested and incubated with phorbol-12-myristate-13-acetate (PMA) or PMA + EP, and ROS and NET generation was measured. ResultsEP significantly decreased proinflammatory cytokines and MPO-DNA in the LPS model. In addition, EP suppressed NET formation in the intestines of endotoxemic mice. The decrease in NETs induced by EP or DNase-1 alleviated histopathological damage, intestinal cell apoptosis and increased tight junction expression. In vitro, the treatment of EP abolished PMA-induced ROS production and NET formation which could be reversed by H2O2 treatment. Meanwhile, EP also abolished MAPK ERK1/2 and p38 activation during PMA-induced NET formation. ConclusionThis study was the first to demonstrate that EP alleviated NET formation and sepsis-induced intestinal damage through blockage of ROS mediated MAPK ERK1/2 and p38 activation.

Protective effect of ethyl pyruvate on testicular histology and fertilization potential in cyclophosphamide treated mice.

In the present study, we aimed to address the use of ethyl pyruvate (EP) against the harmful effects of cyclophosphamide (CP) treatment. Thirty-nine adult male mice were divided into three groups including control group received normal saline [0.20 mL per day; intraperitoneally (IP)], CP group received CP (15.00 mg kg-1 per week, IP) and CP+EP group received EP (40.00 mg kg-1 per day, IP) along with CP and treated for 35 days. After preparation of paraffin sections and Hematoxylin and Eosin staining, the histomorphometric studies were performed on the testicular tissue. Additionally, the serum superoxide dismutase (SOD) and testosterone level, testis malondialdehyde (MDA) and in vitro fertilization rate were assessed. The results showed an increase in the tubal differentiation index, repopulation index, spermiogenesis index, thickness of testicular capsule, mean distribution of active Sertoli cells, SOD and testosterone levels of the CP+EP group in comparison with the CP group. Moreover, the MDA levels in the CP+EP group were lower than the CP group. An increase occurred in the percentage of fertilization in the CP+EP group compared to the CP group. Results of this study revealed that the EP ameliorates deleterious side effects of CP on testicular histology and in vitro fertility.

Hepatoprotective effects of ethyl pyruvate against carbon tetrachloride-induced oxidative stress, biochemical and histological alterations in rats

This study investigated the protective effects of ethyl pyruvate (EP) against carbon tetrachloride (CCl4)-induced acute hepatic injury in rats. The administration of a single dose of CCl4 (1.6 g/kg body weight) significantly elevated the levels of malondialdehyde, nitric oxide, alanine transaminase, aspartate transaminase, and alkaline phosphatase, cholesterol, low-density lipoprotein cholesterol, and triglycerides. In addition, CCl4 was found to significantly suppress the activity of superoxide dismutase, catalase, and glutathione peroxidase. All of these parameters were restored to their normal levels by the administration of EP before and after the CCl4 injection. Moreover, the number of positive apoptotic hepatocytes had significantly increased in the CCl4 group but decreased in rats treated with EP along with CCl4. Histopathological changes induced by CCl4 were also ameliorated by EP treatment. These findings provided evidence that EP, because of its antioxidant and anti-apoptotic action, could protect rat liver against CCl4-induced acute liver injury.

Protective Effect of Ethyl Pyruvate against Myocardial Ischemia Reperfusion Injury through Regulations of ROS-Related NLRP3 Inflammasome Activation.

Emerging evidence indicates the pronounced role of inflammasome activation linked to reactive oxygen species (ROS) in the sterile inflammatory response triggered by ischemia/reperfusion (I/R) injury. Ethyl pyruvate (EP) is an antioxidant and conveys myocardial protection against I/R injury, while the exact mechanisms remain elusive. We aimed to investigate the effect of EP on myocardial I/R injury through mechanisms related to ROS and inflammasome regulation. The rats were randomly assigned to four groups: (1) sham, (2) I/R-control (IRC), (3) EP-pretreatment + I/R, and (4) I/R + EP-posttreatment. I/R was induced by a 30 min ligation of the left anterior descending artery followed by 4 h of reperfusion. EP (50 mg/kg) was administered intraperitoneally at 1 h before ischemia (pretreatment) or upon reperfusion (posttreatment). Both pre- and post-EP treatment resulted in significant reductions in myocardial infarct size (by 34% and 31%, respectively) and neutrophil infiltration. I/R-induced myocardial expressions of NADPH oxidase-4, carnitine palmitoyltransferase 1A, and thioredoxin-interacting protein (TXNIP) were mitigated by EP. EP treatment was associated with diminished inflammasome activation (NOD-like receptor 3 (NLRP3), apoptosis-associated speck-like protein, and caspase-1) and interleukin-1β induced by I/R. I/R-induced phosphorylation of ERK and p38 were also mitigated with EP treatments. In H9c2 cells, hypoxia-induced TXNIP and NLRP3 expressions were inhibited by EP and to a lesser degree by U0126 (MEK inhibitor) and SB203580 (p38 inhibitor) as well. EP's downstream protective mechanisms in myocardial I/R injury would include mitigation of ROS-mediated NLRP3 inflammasome upregulation and its associated pathways, partly via inhibition of hypoxia-induced phosphorylation of ERK and p38.

Prophylactic effect of ethyl pyruvate on renal ischemia/reperfusion injury mediated through oxidative stress.

As oxidative stress (OXS) has been shown to play a primary role in renal ischemia/reperfusion injury (RIRI), we investigated whether antioxidant such as ethyl pyruvate (EPy) might effectively prevent RIRI. Possible prophylactic effects of EPy and mannitol (Mann), one of perioperative agents often used, were tested against harmful OXS in vitro. Hydrogen peroxide (H2O2) was used to exert OXS on the renal proximal tubular MDCK cells. Severity of OXS and protective effects of EPy and Mann were assessed by lipid peroxidation assay and cell viability test, respectively. The cytotoxic mechanism of H2O2 was explored by examining the status of glycolysis, metabolic signaling pathways, cell cycle, and induction of apoptosis. Although H2O2 (500 µM) increased OXS by ~ 3.5 times of controls, EPy (1mM) fully reduced it to the basal level. Cell viability declined to merely 10% by H2O2 was regained to > 90% with EPy. Hexokinase activity and ATP level also declined significantly by H2O2, but they sustained 80-90% with EPy. Additionally, H2O2 led to the modulations of metabolic signaling regulators, a G1 cell cycle arrest, and induction of apoptosis, which were yet prevented with EPy. Unlike EPy, Mann had virtually little effects. OXS can indeed lead to the significant cell viability reduction through its adverse cellular effects, ultimately resulting in RIRI. However, EPy appears to prevent these effects and protect MDCK cells, while Mann does not. Thus, EPy could be a more effective prophylactic renoprotective agent (than Mann) against oxidative renal cell injury including RIRI.

Ethyl pyruvate prevents from chronic cerebral hypoperfusion via preserving cognitive function and decreasing oxidative stress, caspase 3 activation and IL-1β level.

One of the important risk factors for dementia is chronic cerebral hypoperfusion (CCH) especially in patients with cerebrovascular disease. In the present study, using rat model of bilateral common carotid artery occlusion, the possible protective effects of ethyl pyruvate (EP) have been explored in terms of memory impairment, oxidative stress, and levels of caspase-3, Na-K ATPase, and IL- 1β. Rats were treated with EP (50 mg/kg, i.p) for 4 weeks. Cognitive function was evaluated by Morris Water Maze (MWM). Both levels of caspase-3 and Na-K ATPase in tissue, IL-1β in plasma were measured by ELISA method. Status of oxidative stress in brain was assessed by the measurements of the tissue malondialdehyde (MDA) and reduced glutathione (GSH) contents. RESULTS: Results showed that CCH caused a striking impairment of spatial working memory, accompanied with increased levels of MDA and IL-1β as well as caspase 3 level. The treatment with EP, however, significantly improved the memory impairment. Moreover, the treatment also provided beneficial effects on the disturbances of caspase 3, IL-1β and MDA. This study strongly imply that the EP administration can alleviate the memory impairment observed due to CCH. The protection provided by EP may result from inhibition of inflammatory response, apoptotic processes and oxidative stress (Fig. 3, Ref. 58).

Anti-apoptotic and myocardial protective effects of ethyl pyruvate after regional ischaemia/reperfusion myocardial damage in an in vivo rat model.

The integration of reactive oxygen species is strongly associated with important pathophysiological mechanisms that mediate myocardial ischaemia/reperfusion (I/R) damage. Pyruvate is an efficacious scavenger of reactive oxygen species and a previous study has shown that ethyl pyruvate (EP) has a myocardial protective effect against regional I/R damage in an in vivo rat model. The purpose of this study was to determine whether the myocardial protective effect of EP is associated with anti-apoptosis. Rats were allocated to receive EP dissolved in lactated Ringer's solution or lactated Ringer's solution alone, via intraperitoneal infusion one hour before ischaemia. They were exposed to 30 minutes of ischaemia followed by reperfusion of the left coronary artery territory over two hours. Anti-apoptotic effects were checked using several biochemical parameters after two hours of reperfusion. Apoptosis was analysed using measured caspase-3 activity, Western blotting of B-cell lymphoma 2 (Bcl-2) family protein cleaved by caspase-3, and assessment of DNA laddering patterns and the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) staining test. In ischaemic myocardium, EP increased Bcl-2 expression, but reduced Bcl-2-associated X protein and cleaved caspase-3 expressions. EP reduced the expression of DNA laddering and the number of myocardial I/R-damaged TUNEL-positive cells. This study demonstrated that EP has an anti-apoptotic effect after regional I/R damage in an in vivo rat heart model. The myocardial protective effect of EP may be related to its anti-apoptotic effect.

Ethyl pyruvate reverses development of Pseudomonas aeruginosa pneumonia during sepsis-induced immunosuppression

Sepsis is characterized by an innate immune response and the following immune dysfunction which can increase the emergence of secondary infections. Ethyl pyruvate (EP) has multiple immunoregulation functions in several serious illnesses, such as burn injury, severe sepsis and acute respiratory syndrome. However, little data was shown the effect of EP administration on immunosuppression post-CLP and the following secondary infection. The cecal ligation and puncture (CLP) followed by the induction of Pseudomonas aeruginosa (PA) was used as a clinically relevant two-hit model of sepsis. We assessed the survival rate, lung damage and lung bacterial clearance in vehicle or EP treatment group to demonstrate the lung response to Pseudomonas aeruginosa of septic mice. Then cytokines including lung IL-6, IL-1β, IL-10 and plasma HMGB1, apoptosis of splenic immune cells and Foxp3 level on regulatory T cells (Tregs) were studied to demonstrate the mechanisms of EP administration on two-hit mice. We found that the susceptibility of septic mice to Secondary Pseudomonas aeruginosa pneumonia could be down-regulated by ethyl pyruvate treatment and the protective effects of EP may via decreasing lung IL-10 and plasma HMGB1 expression, inhibiting the function of Tregs and relieving the apoptosis of splenic immune cells. The “immune paralysis” post-sepsis still remains a rigorous challenge for curing sepsis, our study may aid in the development of new therapeutic strategies to this problem.

Protective effects of ethyl pyruvate on lipopolysaccharide‑induced acute lung injury through inhibition of autophagy in neutrophils.

Among a number of clinical factors, bacterial infection is one of the most common causes of acute lung injury (ALI), a serious complication that carries a high risk of mortality (~40%). During the process of ALI, intense local and systemic inflammation is elicited, which exacerbates the injury. Neutrophil infiltration into airspace is observed in early stage of ALI, and is required for the full development of ALI through an array of mechanisms, including the release of granule contents and the production of pro-inflammatory cytokines, due to the overactivation of complement and cytokines. The present study noted that ethyl pyruvate alleviated ALI in lipopolysaccharide (LPS)-induced ALI mice. Increased autophagy in neutrophils from ALI mice was observed, while ethyl pyruvate diminished autophagy in neutrophils and constrained granule release, and therefore myeloperoxidase (MPO) in bronchoalveolar lavage fluid and the production of proinflammatory cytokines. Using neutrophil cells, it was identified that autophagy was required for neutrophil activation and granule release, and that ethyl pyruvate caused neutrophil autophagy, leading to the restriction of granule release, and thus contributing to the mitigation of ALI. If autophagy was obviated through knockdown of key regulator of autophagy Atg5, the effects of ethyl pyruvate on granule release by neutrophils disappeared. Taken together, the results demonstrated that ethyl pyruvate alleviates ALI through inhibition of autophagy-induced granule release by neutrophils, and this mechanism suggested a novel potential therapeutic target in autophagy regulation for ALI.

Ethyl Pyruvate Ameliorates The Damage Induced by Cyclophosphamide on Adult Mice Testes.

Cyclophosphamide (CP) is a chemotherapy drug which causes deleterious effects on testicular tissue and increases free radicals in the body. The aim of this study is to investigate the protective effects of ethyl pyruvate (EP) on testicular improvement in CP treated animals. In this experimental study, 15 male mice (6-8 weeks) were divided into 3 groups. The control group received normal saline (0.1 ml/day), intraperitoneal (IP), CP group received CP (15 mg/kg/week, IP), and the CP+EP group received EP (40 mg/kg/day, IP) plus CP. After 35 days, we assessed serum total antioxidant capacity (TAC) along with histomorphometric and histochemical analyses of the testicles. The mean thickness of the germinal epithelium, diameter of seminiferous tubules, and the number of Leydig cells in the CP+EP group were higher than those of the CP group (P<0.05). The number of the mast cells in the CP+EP group significantly reduced compared with the CP group (P<0.05). Alkaline phosphatase (ALP), periodic acid-schiff (PAS) positive reactions and lipid granules in cytoplasm of the Leydig cells in the CP group increased compared with the other groups (P<0.05). TAC in the CP group significantly reduced compared with the other groups (P<0.05). This study showed the ability of EP to reduce the destructive side effects of CP in the adult mice reproductive system.

Protective effect of ethyl pyruvate on ischemia–reperfusion injury in rat ovary: biochemical and histopathological evaluation

BackgroundTo investigate the protective effect of ethyl pyruvate (EP), an anti-oxidant agent, against ischemia–reperfusion injury in a rat model of ovarian torsion, considering biochemical and histopathological aspects. MethodsForty Wistar Albino rats were divided into five groups: Group I, sham operation; Group II, ischemia alone, Group III, ischemia–reperfusion; Group IV, ischemia–reperfusion+50mg/kg EP; and Group V, ischemia–reperfusion+100mg/kg EP. Through laparotomy, 360° torsion was performed and maintained for 3h, and detorsion was maintained for a further 3h. Intraperitoneal EP was given 30min before the surgical procedure. Ovarian tissues and blood samples were obtained after surgery. Malondialdehyde (MDA) and asymmetric dimethyl arginine (ADMA) levels were measured in both plasma and tissue samples. Tissue sections were evaluated histopatologically. Analysis of variance was used for statistical analyses. ResultsIn both serum and tissue samples, ADMA and MDA levels were found to be significantly lower in the EP groups compared with the ischemia alone and ischemia–reperfusion groups (p=0.0001). However, no significant difference was found between groups treated with 50mg/kg or 100mg/kg EP. On histopathological evaluation, the total tissue injury score was found to be lower in rats treated with EP. No significant difference was detected between groups treated with 50mg/kg or 100mg/kg EP. ConclusionEthyl pyruvate may exert positive effects in ischemia–reperfusion injury in cases of ovarian torsion. However, no difference was detected between 50mg/kg and 100mg/kg EP.

Protective effects of ethyl pyruvate in cisplatin-induced nephrotoxicity

This study was performed to investigate the effect of ethyl pyruvate on changes in renal functions and oxidative stress related renal injury caused by cisplatin (cis-dichlorodiammine platinum-II; CDDP).Male Wistar albino rats were divided into four groups (n = 8): (1) control group (1 ml Ringer's lactate solution i.p.); (2) ethyl pyruvate (EP) group (50 mg/kg Ringer's EP solution (REPS) i.p.); (3) cisplatin group (a single dose of cisplatin (5 mg/kg, i.p.); and (4) cisplatin + EP group (a single dose of cisplatin (5 mg/kg, i.p.) + REPS 50 mg/kg/day, i.p.) for five days. At the sixth day, kidneys of rats were mounted to a Langendorff apparatus. Renal perfusion pressures were recorded. Blood samples were taken for serum urea, creatinine, total oxidant status (TOS), total antioxidant status (TAS) and oxidative stres index (OSI) evaluations. Kidney tissues were obtained for malondialdehyde (MDA) analyses and histopathological examination.Perfusion pressures, serum urea, creatinine, TOS, OSI and tissue MDA levels were found significantly higher, whereas TAS was notably lower in cisplatin group. Histopathological examination showed apparent renal paranchymal injury in cisplatin group. In cisplatin + REPS group, perfusion pressures, serum urea, creatinine and tissue MDA levels were decreased. Moreover, EP co-administration provided less inflammatory cell infiltration, tubular dilatation, whereas TOS, TAS and OSI improved significantly versus cisplatin group.These findings show that EP has protective effects against cisplatin nephrotoxicity.

Ethyl Pyruvate Pretreatment Attenuates Concanavalin A-Induced Autoimmune Hepatitis in Mice

Pharmacological RelevanceEthyl pyruvate (EP), a potent reactive oxygen species scavenger, has been reported to contribute to the inflammatory process. However, the protective effect of ethyl pyruvate on Concanavalin A (Con A)-induced autoimmune hepatitis have not been explored. Thus, the aims of this study are to investigate both the effects of ethyl pyruvate and its mechanism of protection on Con A-induced autoimmune hepatitis in mice.Materials and MethodsAcute autoimmune hepatitis was induced by Con A (20 mg/kg) in Balb/C mice; ethyl pyruvate (40 mg/kg and 80 mg/kg) was administrated 1h prior to the Con A injection. At 3h, 6h and 24h post Con A injection, histological grading, proinflammatory cytokine levels and nuclear factor kappa B (NF-κB) activity were determined.ResultsFollowing Con A challenge, cytokines TNF-α, IL-2, IL-1β and IL-6 were expressed at 3h and 6h, and the level of HMGB1 significantly increased by 24h. Pretreatment with ethyl pyruvate ameliorated the pathological effects of Con A-induced autoimmune hepatitis and significantly decreased the levels of TNF-α, IL-2, IL-6 and IL-1β at 3h and 6h and the level of HMGB1 at 6h and 24h post injection. Ethyl pyruvate blocked the degradation of IκB α and IκB β and decreased the expression of NF-κB at 24h.ConclusionTaken together, these results indicated that ethyl pyruvate protected against Con A-induced autoimmune hepatitis by decreasing both early (TNF-α, IL-2, IL-1β and IL-6) and late (HMGB1) cytokine expression in mice. The reduction of HMGB1 may correlate with the amelioration of NF-κB activity.

Ethyl Pyruvate Prevents Methyglyoxal-Induced Retinal Vascular Injury in Rats

Pyruvate is an endogenous antioxidant substance. The aim of this study was to investigate the protective effects of ethyl pyruvate (EP) on retinal vascular injury in diabetic retinopathy. To investigate the protective effect of EP on vascular cell apoptosis and blood-retinal barrier (BRB) breakage, we have used intravitreally methylglyoxal-(MGO-) injected rat eyes. Apoptosis of the retinal vascular cell that was stimulated by the intravitreal injection of MGO was evidently attenuated by the EP treatment. EP exerts inhibitory effect on MGO-induced vascular cell apoptosis by blocking oxidative injury. In addition, EP treatment prevented MGO-induced BRB breakage and the degradation of occludin, an important tight junction protein. These observations suggest that EP acts through an antioxidant mechanism to protect against oxidative stress-induced apoptosis in retinal vessels.

Ethyl pyruvate protects against lipopolysaccharide-induced white matter injury in the developing rat brain

The neuroprotective effects of ethyl pyruvate (EP) have been proved in several brain injury models, yet very little is known about its action on neonatal white matter injury. To investigate the effect of EP on white matte damage, a stereotactic intracerebral injection of lipopolysaccharide (LPS, 1mg/kg) was performed on postnatal day 5 Sprague–Dawley rat pups, and EP was administrated intraperitoneally at a dose of 40mg/kg immediately, 1h and 12h after LPS exposure. Significantly, treatment with EP reduced LPS-induced ventricle dilation, loss of O4+ and O1+ oligodendrocytes, apoptosis of oligodendrocytes, and hypomyelination. The protective effect of EP was associated with suppressed inflammatory responses, indicated by the inhibition of activation of microglia and astrocytes, as well as the decreased expression of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β) in rat brains. Also, EP prevented the elevation of cleaved caspase-3 in periventricular white matter tissue after LPS insult. Taken together, these results suggest that EP confers potent protection against LPS-induced white matter injury via its anti-inflammatory and anti-apoptotic properties.

Protective effect of ethyl pyruvate on pancreas injury in rats with severe acute pancreatitis

BackgroundSystemic inflammatory mediators have an important role in the development of acute pancreatitis. In this study, we investigated the effect of ethyl pyruvate (EP) on pancreas injury in rats with severe acute pancreatitis (SAP) and its possible mechanism. MethodsWe randomly allocated rats into the following three experimental groups: control and SAP- and EP-treated. Then, we recorded the mortality rate. We harvested tissue specimens for morphological studies, streptavidin-peroxidase immunohistochemistry examination, and Western blot analysis. We tested the levels of pancreatic tissue malondialdehyde and the activity of serum amylase, myeloperoxidase in the pancreas. In addition, we studied nuclear factor-κB (NF-κB) activation, tumor necrosis factor-α levels, and high mobility group box 1 protein expression levels in the pancreas. ResultsTreatment with EP after SAP was associated with a reduction in the severity of SAP and pancreas injury. Treatment with EP significantly decreased the expression of tumor necrosis factor-α and high mobility group box 1, and ameliorated malondialdehyde concentration and myeloperoxidase activity in the pancreas in SAP rats. Compared with the SAP group, treatment with EP significantly decreased the number of inflammatory cell infiltration, markedly inhibited pancreatic NF-κB DNA binding, and increased the survival rates. ConclusionsThis study demonstrates that preventing the activation of NF-κB by EP ameliorates tissue injury associated with experimental murine acute pancreatitis. This result provides an important insight into the molecular biology of acute pancreatitis.

Ethyl pyruvate protects against experimental acute-on-chronic liver failure in rats

To investigate the protective effects of ethyl pyruvate (EP) on acute-on-chronic liver failure (ACLF) in rats. An ACLF model was established in rats, and animals were randomly divided into normal, model and EP treatment groups. The rats in EP treatment group received EP (40 mg/kg) at 3 h, 6 h, 12 h and 24 h after induction of ACLF. Serum endotoxin, high mobility group box-1 (HMGB1), alanine transaminase (ALT), tumor necrosis factor-α (TNF-α), interferon-α (IFN-γ), interleukin (IL)-10 and IL-18 levels, changes of liver histology and HMGB1 expressions in liver tissues were detected at 48 h after induction of ACLF. The effects of EP on the survival of ACLF rats were also observed. Serum levels of endotoxin (0.394 ± 0.066 EU/mL vs 0.086 ± 0.017 EU/mL, P < 0.001), HMGB1 (35.42 ± 10.86 μg/L vs 2.14 ± 0.27 μg/L, P < 0.001), ALT (8415.87 ± 3567.54 IU/L vs 38.64 ± 8.82 IU/L, P < 0.001), TNF-α (190.77 ± 12.34 ng/L vs 124.40 ± 4.12 ng/L, P < 0.001), IFN-γ (715.38 ± 86.03 ng/L vs 398.66 ± 32.91 ng/L, P < 0.001), IL-10 (6.85 ± 0.64 ng/L vs 3.49 ± 0.24 ng/L, P < 0.001) and IL-18 (85.19 ± 3.49 ng/L vs 55.38 ± 1.25 ng/L, P < 0.001) were significantly increased, and liver tissues presented severe pathological injury in the model group compared with the normal group. However, EP administration significantly improved hepatic histopathology and reduced the serum levels of endotoxin (0.155 ± 0.045 EU/mL vs 0.394 ± 0.066 EU/mL, P < 0.001) and inflammatory cytokines (11.13 ± 2.58 μg/L vs 35.42 ± 10.86 μg/L for HMGB1, 3512.86 ± 972.67 IU/L vs 8415.87 ± 3567.54 IU/L for ALT, 128.55 ± 5.76 ng/L vs 190.77 ± 12.34 ng/L for TNF-α, 438.16 ± 38.10 ng/L vs 715.38 ± 86.03 ng/L for IFN-γ, 3.55 ± 0.36 ng/L vs 6.85 ± 0.64 ng/L for IL-10, and 60.35 ± 1.63 ng/L vs 85.19 ± 3.49 ng/L for IL-18, respectively, P < 0.001), and the levels of HMGB1 in liver tissues regardless of treatment time after induction of ACLF. EP treatment at the four time points prolonged the median survival time of ACLF rats (60 h) to 162 h, 120 h, 102 h and 78 h, respectively (χ(2) = 41.17, P < 0.0001). EP administration can protect against ACLF in rats, and is a potential and novel therapeutic agent for severe liver injury.