Protective Effect Of Valproic Acid Research Articles

Protective effect of valproic acid on ischemia-reperfusion induced spinal cord injury in a rat model

Purpose This study aims to determine the anti-inflammatory, antioxidant, and anti-apoptotic effects of valproic acid (VPA) on rat spinal cord tissue in ischemia-reperfusion (IR) injury model created by abdominal aorta occlusion. Materials and Methods Sprague Dawley rat (male sex) weighing 190–260 g divided into four experimental groups: control only underwent laparotomy, sham group, pre-IR injury (200 mg/kg dose), and post-IR injury (300 mg/kg) VPA. We measured serum levels of TNF-α, IL-6, IL-1β, IL-18, Total Oxidant Status (TOS) and Total Antioxidant Status (TAS), and serum Oxidative Stress Index (OSI) ratio, and tissue expression of Bax and Bcl2, Caspase3, and Bax/Bcl2 ratio. Results Serum IL-18 was higher in the sham than the control group(P = 0.001), and there were declines in the pre-IR treatment (P = 0.002) and the post-IR treatment when compared to sham (P = 0.001). Despite these reductions, IL-18 expression levels in both the pre- and post-IR treatment groups were higher than in the control group (P = 0.001 & P = 0.003). The favorable effects of pre-IR VPA administration on immunohistochemical biomarkers were superior to post-IR VPA administration. Conclusions Comparative analyses between prophylactic VPA administration and post-IR interventions revealed congruence in their anti-inflammatory and anti-apoptotic ramifications. VPA can reduce spinal cord IR injury in an aortic occlusion model of rats.

Study on the protective effect of sodium valproic acid on carbonyl cyanide 3-chlorophenylhydrazone-induced oxidative stress injury in osteoblasts

To explore the protective effects of sodium valproic acid (VPA) on oxidative stress injury of osteoblasts induced by carbonyl cyanide 3-chlorophenylhydrazone (CCCP) and its mechanism. Osteoblasts were isolated from the skulls of 10 newborn Sprague Dawley rats and cultured by tissue block method, and the 1st generation cells were identified by alkaline phosphatase (ALP) and alizarin red staining. The 3rd generation osteoblasts were cultured with 2-18 μmol/L CCCP for 2-18 minutes, and cell counting kit 8 (CCK-8) was used to detect the cell survival rate. An appropriate inhibitory concentration and culture time were selected for the preparation of osteoblasts oxidative stress injury model based on half maximal concentration principle. The cells were cultured with 0.2- 2.0 mmol/mL VPA for 12-72 hours, and CCK-8 was used to detect cell activity, and appropriate concentration was selected for further treatment. The 3rd generation cells were randomly divided into 4 groups, including blank control group (normal cultured cells), CCCP group (the cells were cultured according to the selected appropriate CCCP concentration and culture time), VPA+CCCP group (the cells were pretreated according to the appropriate VAP concentration and culture time, and then cultured with CCCP), VPA+CCCP+ML385 group (the cells were pretreated with 10 μmol/L Nrf inhibitor ML385 for 2 hours before VPA treatment, and other treatments were the same as VPA+CCCP group). After the above treatment was complete, the cells of 4 groups were taken to detect oxidative stress indicators [reactive oxygen species (ROS), superoxide dismutase (SOD), malondialdehyde (MDA)], cell apoptosis rate, ALP/alizarin red staining, and the relative expressions of osteogenic related proteins [bone morphogenetic protein 2 (BMP-2), RUNX2], anti-apoptotic family protein (Bcl2), apoptotic core protein (Cleaved-Caspase-3, Bax), channel protein (Nrf2) by Western blot. The osteoblasts were successfully extracted. According to the results of CCK-8 assay, the oxidative stress injury model was established by 10 μmol/L CCCP cultured for 10 minutes and 0.8 mmol/mL VPA cultured for 24 hours was selected for subsequent experiments. Compared with blank control group, the activity and mineralization capacity of osteoblasts in CCCP group decreased, the contents of ROS and MDA increased, the activity of SOD decreased, and the apoptosis rate increased. Meanwhile, the relative expressions of BMP-2, RUNX2, and Bcl2 decreased, and the relative expressions of Cleaved-Caspase-3, Nrf2, and Bax increased. The differences were significant ( P<0.05). After further VPA treatment, the oxidative stress damage of osteoblasts in VPA+CCCP group was relieved, and the above indexes showed a recovery trend ( P<0.05). In VPA+CCCP+ML385 group, the above indexes showed an opposite trend ( P<0.05), and the protective effects of VPA were reversed. VPA can inhibit the CCCP-induced oxidative stress injury of osteoblasts and promote osteogenesis via Keap1/Nrf2/Are pathway.

Valproic Acid Attenuated PTZ-induced Oxidative Stress, Inflammation, and Apoptosis in the SH-SY5Y Cells via Modulating the TRPM2 Channel.

Valproic acid (VPA) is one of the most widely used antiepileptic drugs. The protective role of VPA and the role of the TRPM2 channel in this mechanism in developing neuronal damage due to increased pentylenetetrazol (PTZ)-induced neurotoxicity in SH-SY5Y cells were not clarified. Here, we investigated the role of VPA via modulation of TRPM2 channelon cell death and oxidative neurotoxicity in SH-SY5Y cells. The SH-SY5Y cell toxicity model was constructed by treating SH-SY5Y cells with PTZ. The VPA and TRPM2 channel antagonistN-(p-amylcinnamoyl)anthranilic acid (ACA) were added to prevent neurotoxicity in PTZ-induced SH-SY5Y cells. The role of the VPA and TRPM2 channel was evaluated using an ELISA kit and patch-clamp. Primarily, antioxidant (GSH and GSH-Px) and oxidative stress (MDA and ROS) levels and inflammatory factors (IL-1β, IL-6, and TNF-α) in cells were determined by ELISA kits. Then, TRPM2 channel activation in cells was detected using both the ELISA kit and patch-clamp methods. In addition, apoptosis and cell viability levels in cells were determined by performing PARP1, caspase-3, caspase-9, and CCK-8 assays by ELISA kits. Our results showed that the TRPM2 channel is vital in damage formation in PTZ-induced cells. Furthermore, we observed that VPA attenuated PTZ-induced neurotoxicity by suppressing cells' oxidative stress and inflammation,and reducing TRPM2 channel activation. In our study, in which the protective effect of VPA and the role of the TRPM2 channel in PTZ-induced SH-SY5Y cells were investigated for the first time, we can conclude that VPA treatment and TRPM2 channel blockade can suppress PTZ-induced neurotoxicity.

Protective effects of valproic acid on 6-hydroxydopamine-induced neuroinjury.

Oxidative stress may play critically important roles in the etiology of Parkinson's disease (PD). 6-Hydroxydopamine (6-OHDA) is a physiological neurotoxin reported to induce oxidative-induced apoptosis of dopaminergic neurons in PD mice models. Valproic acid (VPA), a clinical mood stabilizer, is a HDAC inhibitor with neuroprotective capacities. In the study, we aim at examining the feasibility of VPA as a protector for dopaminergic neurons against damage from 6-OHDA, and the intracellular mechanisms. The 6-OHDA-induced neurotoxicity to the human dopaminergic cell line SH-SY5Y was applied for examining VPA protective effects. Pretreatment with VPA was able to improve cell viability and reduce 6-OHDA-induced reactive oxygen species. Furthermore, a significant suppression of apoptotic caspases including cleaved caspase-3, caspase-7, and caspase-9 was observed. The results also revealed VPA decreased the 6-OHDA-induced Bax/Bcl2 ratio, as measured at protein level. These novel findings indicate that VPA may be capable of protecting the SH-SY5Y dopaminergic neuronal cells from 6-OHDA-induced toxicity via the deceasing of apoptotic caspases (cleaved caspase-3, caspase-7, and caspase-9) and reducing of the Bax/Bcl2 ratio. Very possibly, VPA could serve as not only a mood stabilizer but also a potential antidote for PD prevention.

Valproic acid administration exerts protective effects against stress-related anhedonia in rats

Anhedonia or inability to experience pleasure is the sign of various neuropsychiatric conditions. Current treatment options do not provide adequate control of anhedonia. The present study was conducted to evaluate the protective effects of valproic acid (VPA) as a nonspecific histone deacetylase (HDAC) inhibitor to reverse the effects of stress on induction of anhedonia and explore possible mechanisms.To induce anhedonia, a rat model of chronic unpredictable mild stress (CUMS) was established. Animals were assigned into no stress, stress (6 weeks of CUMS) and two treatment groups. VPA treatment was carried out for 4 continuous weeks (200 mg/kg/day). Behavioral assessments were performed using sucrose consumption (SCT) and new object recognition (NOR) tests. The expression of genes was evaluated using qRT-PCR. The cell density was determined using Nissl staining.Rats with CUMS showed depressive-like behaviors and impaired memory performance compared with the non-stressed group (p < 0.01). Moreover, they had significantly higher levels of HDAC3 and MC4R expression in the nucleus accumbens (NAc) compared to the non-stressed group (p < 0.01). The NAc cell density was significantly higher in the non-stressed rats (p < 0.05). Corticosterone plasma level was increased in the CUMS compared to the non-stressed group (p < 0.05). In the CUMS + VPA subgroup, the corticosterone (CORT) plasma level was lower compared with the CUMS + Saline and/or the CUMS groups (p < 0.05).These findings suggest that VPA can improve anhedonia and stress. Although the protective effect of VPA might link to decreasing HDAC3 and MC4R genes expression in NAc.

Abstract 348: Epigenetic Regulation in Heart Regeneration

Existing treatments for myocardial infarction (MI) include Medication, intervention, and surgical bypass. These strategies are mainly used to prevent disease progression, but do not address the fundamental problem of cardiomyocyte loss. Therefore, developing new effective therapeutic strategies to preserve the pumping function after MI is highly desired. Acute injuries, such as MI, are companied with quick and massive loss of histone acetylation in injured cells, which lead to severe organ damage. Therefore, maintaining proper histone acetylation in a swift manner will likely protect the affected cell and organ function. In this study, we showed that valproic acid (VPA), a pan HDAC inhibitor and a FDA approved drug for epilepsy and bipolar disorders, reduced ~50% of the infarct size and preserves the pumping function of heart after MI in rats. Moreover, 60 min after infarction, VPA administration still significantly decreased infarct size in MI rats. Mechanistically, we identified that that VPA treatment triggered a Foxm1 pathway, which in turn activated genes essential for cell survival and proliferation and inflammation suppression. Importantly, overexpression of Foxm1 provided similar heart protective effect after MI as VPA treatment. In contrast, inhibition of Foxm1 activity abolished the cardiac protective effect of VPA. In parallel, we have applied novel biodegradable nanofibrous microspheres as cell carriers for cell transplantation. These microspheres dramatically improve engraftment of exogenously delivered cells and functional recovery of the infarcted hearts. Intriguingly, the efficacy of cell engraftment appears to correlate with the cell carrier’s ability to maintain the acetylation status of the cells. We expect that the combined HDAC inhibitor treatment with cell carrier-mediated CM transplantation will work synergistically to regenerate infarcted heart functioning and lead to effective clinical applications in heart regeneration therapy.

Protective effect of valproic acid in streptozotocin-induced sporadic Alzheimer's disease mouse model: possible involvement of the cholinergic system.

Sporadic Alzheimer's disease (SAD) is a slowly progressive neurological disorder that is the most common form of dementia. Cholinergic system dysfunction and amyloid beta formation are the two main underlying pathological mechanisms for the disease development. In recent studies, insulin receptor desensitization and disturbances in the downstream effects of insulin receptor signaling were observed in the brains of Alzheimer's patients. Currently, intracereberoventricular (ICV) injection of streptozotocin (STZ) is found to induce behavioral, neurochemical, and structural alterations in animals resembling those found in SAD patients. Valproic acid (VPA), a histone deacetylase inhibitor (HDACi), was recently shown to regulate the transcription of several genes in both in vivo and in vitro models of Alzheimer's disease. The aim of the current study is to investigate the potential effect of different doses of valproic acid, in an ICV-STZ-induced animal model of SAD. Streptozotocin-injected mice showed cognitive and spatial memory dysfunction in the Y-maze, object recognition test, and Morris water maze (MWM) neurobehavioral tests. The mice also exhibited a decrease in acetylcholine (ACh) and neprilysin (NEP) levels accompanied by an increase in acetylcholinesterase (AChE) activity. For the first time to our knowledge, our findings have shown that VPA is capable of restoring ACh levels in ICV-STZ-injected mice, as well as normalizing both NEP levels and AChE activity. Via this mechanism, an enhancement of cognitive functions is observed. Thus, VPA is suggested to be a promising therapeutic approach against SAD.

Inhibition of DNA methyltransferase or histone deacetylase protects retinal pigment epithelial cells from DNA damage induced by oxidative stress by the stimulation of antioxidant enzymes

Epigenetic modifications influence DNA damage response (DDR). In this study we explored the role of DNA methylation and histone acetylation in DDR in cells challenged with acute or chronic oxidative stress. We used retinal pigment epithelial cells (ARPE-19), which natively are exposed to oxidative stress due to permanent exposure to light and high blood flow. We employed a DNA methyltransferase inhibitor – RG108 (RG), or a histone deacetylase inhibitor – valproic acid (VA). ARPE-19 cells were exposed to tert-butyl hydroperoxide, an acute oxidative stress inducer, or glucose oxidase, which slowly liberates low-doses of hydrogen peroxide in the presence of glucose, creating chronic conditions. VA and RG reduced level of intracellular reactive oxygen species and DNA damage in ARPE-19 cells in normal condition and in oxidative stress. This protective effect of VA and RG was associated with the up-regulated expression of antioxidant enzyme genes: CAT, GPx1, GPx4, SOD1 and SOD2. RG decreased the number of cells in G2/M checkpoint in response to chronic oxidative stress. Neither RG nor VA changed the DNA repair or apoptosis induced by oxidative stress. Therefore, certain epigenetic manipulations may protect ARPE-19 cells from detrimental effects of oxidative stress by modulation of antioxidative enzyme gene expression, which may be further explored in pharmacological studies on oxidative stress-related eye diseases.

Protective Effects of Valproic Acid, a Histone Deacetylase Inhibitor, against Hyperoxic Lung Injury in a Neonatal Rat Model.

ObjectiveHistone acetylation and deacetylation may play a role in the pathogenesis of inflammatory lung diseases. We evaluated the preventive effect of valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, on neonatal hyperoxic lung injury.MethodsForty newborn rat pups were randomized in normoxia, normoxia+VPA, hyperoxia and hyperoxia+VPA groups. Pups in the normoxia and normoxia+VPA groups were kept in room air and received daily saline and VPA (30 mg/kg) injections, respectively, while those in hyperoxia and hyperoxia+VPA groups were exposed to 95% O2 and received daily saline and VPA (30 mg/kg) injections for 10 days, respectively. Growth, histopathological, biochemical and molecular biological indicators of lung injury, apoptosis, inflammation, fibrosis and histone acetylation were evaluated.ResultsVPA treatment during hyperoxia significantly improved weight gain, histopathologic grade, radial alveolar count and lamellar body membrane protein expression, while it decreased number of TUNEL(+) cells and active Caspase-3 expression. Expressions of TGFβ3 and phospho-SMAD2 proteins and levels of tissue proinflammatory cytokines as well as lipid peroxidation biomarkers were reduced, while anti-oxidative enzyme activities were enhanced by VPA treatment. VPA administration also reduced HDAC activity while increasing acetylated H3 and H4 protein expressions.ConclusionsThe present study shows for the first time that VPA treatment ameliorates lung damage in a neonatal rat model of hyperoxic lung injury. The preventive effect of VPA involves HDAC inhibition.

Protective effect of valproic acid on cultured motor neurons under glutamate excitotoxic conditions. Ultrastructural study.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder that involves the upper and lower motor neurons and leads to the patient's death within 5 years after diagnosis. Approximately 2 per 100,000 people worldwide are affected every year. The only FDA-approved drug available for medical treatment is riluzole. It slows the disease progression and improves limb function and muscle strength for 3-4 months. Thus, looking for new therapeutic agents is a pressing challenge. Valproic acid (VPA) is a short-chain fatty acid, widely used for the treatment of seizures and bipolar mood disorder. The beneficial effect of VPA has been documented in different neurodegenerative experimental models, including amyotrophic lateral sclerosis (ALS). The real mechanisms underlying numerous beneficial effects of VPA are complex, but recently it has been postulated that the neuroprotective properties might be related to direct inhibition of histone deacetylase (HDAC). The aim of this ultrastructural study was to evaluate the beneficial effect of VPA on the spinal cord motor neurons (MNs) in a glutamate (GLU)-induced excitotoxic ALS model in vitro. It had been previously documented that chronic GLU excitotoxicity resulted in various MN injuries, including necrotic, apoptotic and autophagic modes of cell death. The present results demonstrated the neuroprotective properties of VPA associated with inhibition of apoptotic and autophagic changes of spinal MNs in a model of neurodegeneration in vitro.

The protective effect of valproic acid on myocardium in rats with lethal scald injury and its mechanism

To investigate the protective effects of valproic acid (VPA) on myocardium in rats following lethal burn injury and its mechanism. Seventy-eight Sprague-Dawley (SD) rats were randomly assigned to four groups: sham-scald group (n=10), sham-scald + VPA group (n=10), scald group (n=29), and scald + VPA group (n=29). Rats in the latter two groups were subjected to 55% total body surface area (TBSA) third-degree burns by immersing the back of the trunk for 15 seconds, both lower extremities for 15 seconds, and the abdomen for 8 seconds in 80 centigrade water. Sham-scald rats were immersed in 37 centigrade water instead. Rats were then subcutaneously injected with VPA (300 mg/kg) or normal saline as control. Blood of 5 rats in each group was with drawn from the abdominal aorta at 6 hours after injury for measurement of plasma creatine kinase-MB (CK-MB) activities; then the rats were sacrificed and heart tissues were harvested for the measurement of acetylated histone H3 and activated caspase-3 by Western Blot. The remaining rats were used for 12-hour survival analysis. Compared with sham-scald group, there was a significant increase in plasma CK-MB activities (5 438.0 ± 413.6 U/L vs. 2 881.0 ± 324.8 U/L, P<0.05) and activated caspase-3 protein levels in heart tissue (gray value: 1.75 ± 0.25 vs. 1.00 ± 0.18, P<0.05) and an significant decline in the acetylation levels of histone H3 (gray value: 0.55 ± 0.18 vs. 1.00 ± 0.20, P<0.05) after major burn injury. VPA treatment significantly reduced the plasma CK-MB activities [(4 018.0 ± 388.3) U/L], activated caspase-3 protein levels in heart tissue (gray value: 1.33 ± 0.20), and raised the acetylation levels of histone H3 (gray value: 2.20 ± 0.23, all P<0.05). Survival analysis by Kaplan-Meier curves showed that the survival was improved after VPA treatment, and the survival rate was increased from 0 to 50% at 12 hours (P<0.05). VPA can attenuate cardiac injury and improve survival in a rodent model of lethal burn injury. These protective effects may be due to its inhibitory effects on histone deacetylase and caspase-3 activation.

597 Valproic Acid-Mediated Protection Against Hyperoxic Lung Injury Via Histone Deacetylase Inhibition in a Neonatal Rat Model

Epigenetic mechanisms might play an important role in development of BPD. The aim of this study was to evaluate the protective effect of valproic acid (VPA), an histon deacetylase inhibitor,...

Protective effects of valproic acid against airway hyperresponsiveness and airway remodeling in a mouse model of allergic airways disease

Airway remodeling and airway hyperresponsiveness are major aspects of asthma pathology that are not targeted optimally by existing anti-inflammatory drugs. Histone deacetylase inhibitors have a wide range of effects that may potentially abrogate aspects of remodeling. One such histone deacetylase inhibitor is valproic acid (2-propylvaleric acid). Valproic acid is used clinically as an anti-epileptic drug and is a potent inhibitor of class I histone deacetylases but also inhibits class II histone deacetylases. We used valproic acid as a molecular model of histone deacetylase inhibition in vivo in chronic allergic airways disease mice with airway remodeling and airway hyperresponsiveness. Wild-type Balb/c mice with allergic airways disease were treated with valproic acid or vehicle control. Airway inflammation was assessed by bronchoalveolar lavage fluid cell counts and examination of lung tissue sections. Remodeling was assessed by morphometric analysis of histochemically stained slides and lung function was assessed by invasive plethysmography measurement of airway resistance. Valproic acid treatment did not affect inflammation parameters; however, valproic acid treatment resulted in reduced epithelial thickness as compared to vehicle treated mice(p < 0.01), reduced subepithelial collagen deposition (p < 0.05) and attenuated airway hyperresponsiveness (p < 0.05 and p < 0.01 for the two highest doses of methacholine, respectively). These findings show that treatment with valproic acid can reduce structural airway remodeling changes and hyperresponsiveness, providing further evidence for the potential use of histone deacetylase inhibitors for the treatment of asthma.

Valproic Acid Attenuates Proteinuria and Kidney Injury

Inhibitors of histone deacetylase (HDAC) have anti-inflammatory and antifibrotic effects in several organs and tissues, but their effect on the progression of renal disease is unknown. Here, we studied the effect of valproic acid in adriamycin-induced nephropathy in mice. Administration of valproic acid before kidney injury prevented the development of proteinuria and the onset of glomerulosclerosis. Even after postponing treatment until the peak of adriamycin-induced proteinuria, valproic acid rapidly decreased the quantity of proteinuria and attenuated the progression of renal disease. Valproic acid abrogated the decrease in glomerular acetylation observed during adriamycin-induced nephropathy. Furthermore, valproic acid attenuated the significant upregulation of profibrotic and proinflammatory genes, the deposition of collagen, and the infiltration of macrophages into the kidney. Valproic acid decreased glomerular apoptosis and proliferation induced by adriamycin. Ultrastructural studies further supported the protective effect of valproic acid on podocytes in this model. Taken together, these data suggest that HDACs contribute to the pathogenesis of renal disease and that HDAC inhibitors may have therapeutic potential in CKD.

Protective effects of valproic acid on the nigrostriatal dopamine system in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine mouse model of Parkinson's disease

The use of animal models (including the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine [MPTP] mouse model) to mimic dopaminergic (DAergic) cell loss and striatal dopamine (DA) depletion, as seen in Parkinson's disease (PD), has implicated a multitude of factors that might be associated with DAergic cell death in PD including excitotoxicity, inflammation, and oxidative stress. All of these factors have been shown to be reduced by administration of histone deacetylase (HDAC) inhibitors (HDACis) resulting in some degree of neuroprotection in various models of neurodegenerative disease including in Huntington's disease and amyotrophic lateral sclerosis. However, there is limited information of effects of HDACis in PD models. We have previously shown HDACis to be partially protective against 1-methyl-4-phenylpyridinium (MPP(+))-mediated cell loss in vitro. The present study was conducted to extend these findings to an in vivo PD model. The HDACi valproic acid (VPA) was co-administered with MPTP for 5 days to male FVBn mice and continued for an additional 2 weeks, throughout the period of active neurodegeneration associated with MPTP-mediated DAergic cell loss. VPA was able to partially prevent striatal dopamine depletion and almost completely protect against substantia nigra DAergic cell loss. These results suggest that VPA may be a potential disease-modifying therapy for PD.

Protective effects of valproic acid on lipopolysaccharide-induced acute lung injury in rats

Objective To investigate the effects of valproic acid (VPA) on acute lung injury induced by Lipopolysaccharide in rats. Method The rat model of acute lung injury was made by intravenous injection of lipopolysaccharide (LPS). The pathological changes of lung were observed under light microscope and inflammatory cytokines in serum detected by using ELISA to judge whether the model was successfully done or not. All rats were divided into three groups as per the different intervention agents employed. Rats in control group were treated with intravenous injection of NS in dose of 5 ml/kg, rats in LPS group were exposed to LPS with dosage of 10 mg/kg and model rats in LPS + VPA group were treated with VPA in dose of 300 mg/kg. The rats were sacrificed 6 h after LPS or NS administration. The blood PaO2 ,A-aDO2 and blood lactic acid (Lac) were measured, the lungs were removed for observing the histopathological changes and determination of wet/dry lung weight (W/D) ratio and myeloperoxidase (MPO) activity as well as albumin concentration in broncho-alveolar lavage fluid (BALF) . Seurm was collected to determine the concentrations of tumor necrosis factor-a (TNF-α) and interleukin-1β( IL-1 β) by using LISA 6 h later. All data were presented in ((x)±s). One-way ANOVA was used for comparing differences between groups. Results Compared with acute lung injury group, the blood PaO2 (94. 50 ± 4.38 ) in rats of LPS + VPA group was higher, whereas A-aDO2 ( 13.50 ± 4.77 ) and blood lac( 2.13 ± 1. 02 ) in LPS + VPA group were lower. VPA significantly lowered W/D (5.33 ±0. 12) ratio and MPO activity (4.38 ±0. 42) in the lung. Albumin concentration ( 1. 260 ± 0. 039 ) in BALF, and the levels of TN F-α( 2 410 ±320 )and IL-1β( 1 220 ± 162 )in serum were lower in LPS + VPA group. The histological changes of lung injury were lessened by VPA. Conclusions Valproic acid has protective effects against lipopolysaccharide-induced acute lung injury in rats. Key words: Valproic acid; Lipopolysaccharide; Acute lung injury; Tumor necrosis factor-alpha; Interleukin-1 belta

Histone deacetylase inhibitors up-regulate astrocyte GDNF and BDNF gene transcription and protect dopaminergic neurons

Parkinson's disease (PD) is characterized by the selective and progressive loss of dopaminergic (DA) neurons in the midbrain substantia nigra. Currently, available treatment is unable to alter PD progression. Previously, we demonstrated that valproic acid (VPA), a mood stabilizer, anticonvulsant and histone deacetylase (HDAC) inhibitor, increases the expression of glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF) in astrocytes to protect DA neurons in midbrain neuron-glia cultures. The present study investigated whether these effects are due to HDAC inhibition and histone acetylation. Here, we show that two additional HDAC inhibitors, sodium butyrate (SB) and trichostatin A (TSA), mimic the survival-promoting and protective effects of VPA on DA neurons in neuron-glia cultures. Similar to VPA, both SB and TSA increased GDNF and BDNF transcripts in astrocytes in a time-dependent manner. Furthermore, marked increases in GDNF promoter activity and promoter-associated histone H3 acetylation were noted in astrocytes treated with all three compounds, where the time-course for acetylation was similar to that for gene transcription. Taken together, our results indicate that HDAC inhibitors up-regulate GDNF and BDNF expression in astrocytes and protect DA neurons, at least in part, through HDAC inhibition. This study indicates that astrocytes may be a critical neuroprotective mechanism of HDAC inhibitors, revealing a novel target for the treatment of psychiatric and neurodegenerative diseases.