Status epilepticus stimulates peroxisome proliferator-activated receptor γ coactivator 1-α/mitochondrial antioxidant system pathway by a nitric oxide-dependent mechanism

Glucose-PEG2000-DSPE modified carbamazepine nano system alleviated cell apoptosis and oxidative stress in epilepsy

Investigations on the effects of newly constructed glucose-PEG2000-DSPE modified carbamazepine nano system on oxidative stress damage and cell apoptosis in epilepsy. The nano system was constructed by egg yolk lecithin, cholesterol, GLUPEG2000-DSPE, and carbamazepine as per the molar ratio of 95:20:5:6.35. The particle size, zeta potential, and release rate of carbamazepine was determined using a microscope and a microplate reader. The cells toxicity was detected for determine the optimal concentration of carbamazepine nano system. Cell uptake, cell apoptosis ratio and ROS level was determined by flow cytometry analysis. The in vivo studies were performed using male Wistar rats. H&E staining was employed for histological evaluation. Immunofluorescence was utilized for measure the expression level of GLUT1. ELISA assay was obtained for detecting the levels of SOD, GSH-Px and MDA. The results shown the average particle size was 108.57 ± 3.42 nm, and the mean zeta potential was -52.75 ± 1.48 mV. The modified carbamazepine liposomes exhibited higher release rate. Cell uptake indicated that carbamazepine nano system could be successfully internalized into cells. Flow cytometry analysis revealed the carbamazepine nano system dramatically decreased cell apoptosis rate and downregulated ROS level. Moreover, carbamazepine nano system improved histological status, increased GLUT1 expression and decreased oxidative stress in vivo. In conclusion, glucose-PEG2000-DSPE modified carbamazepine nano system ameliorated cell apoptosis and oxidative stress damage in epilepsy.

Evaluation of silent information regulator T (SIRT) 1 and Forkhead Box O (FOXO) transcription factor 1 and 3a genes in glaucoma

Analysis of the reactive oxygen species (ROS)-detoxifying biomarkers may elucidate the mitochondrial dysfunction in glaucoma pathogenesis. Therefore, we purposed to investigate the effects of ROS-detoxifying molecules including Silent Information Regulator T1 (SIRT1) and Forkhead Box O 1 (FOXO1) and 3a (FOXO3a) transcription factors in patients with glaucoma. Our analyses included 20 eyes from patients with primary open-angle glaucoma (POAG) and 20 eyes from patients with pseudoexfoliation glaucoma (PXG) who were scheduled for trabeculectomy. After extraction of total RNA from trabecular meshwork tissue, we compared the levels of SIRT1, FOXO1and FOXO3a genes in the oxidative pathway with the level of glyceraldehyde-3 phosphate dehydrogenase (GAPDH), the reference gene, using real-time polymerase chain reaction. Relative gene expression was calculated using the threshold cycle (2^-ΔΔCT) method. We observed similarly reduced expression levels of SIRT1, FOXO1, and FOXO3a genes versus GAPDH among patient groups (p = 0.40; p = 0.56; p = 0.35, respectively). This is the first study to identify the role of SIRT1 and FOXOs in human TM with glaucoma. Relative expression levels of SIRT1, FOXO1, and FOXO3a genes versus a control gene (GAPDH) were decreased in POAG and PXG groups. Our results show that SIRT1and FOXOs (1-3a) deserve special attention in the pathogenesis of glaucoma.

The Role of TLR4 on PGC-1α-Mediated Oxidative Stress in Tubular Cell in Diabetic Kidney Disease

The role and precise mechanism of TLR4 in mitochondria-related oxidative damage and apoptosis of renal tubules in diabetic kidney disease (DKD) remain unclear. We examined the expression of TLR4 in renal biopsy tissues. Db/db diabetic mice and HK-2 cells cultured under high glucose (HG) were used as in vivo and vitro models. Real-time RT-PCR, Western blot, and immunohistochemistry were performed to examine the mRNA and protein levels of TLR4, NF-κΒ, PGC-1α, cytochrome C, and cleaved caspase-3. ATP level, activity of electron transport chain complex III, and antioxidant enzymes were investigated for mitochondrial function. Electron microscopy (EM) and MitoTracker Red CMXRos were used for mitochondrial morphology alteration. DHE staining and TUNEL assay were detected for ROS accumulation and apoptosis. PGC-1α plasmids were used for the overexpression of PGC-1α in HK-2. TAK242 and parthenolide were used as TLR4 and NF-κB blockers, respectively. Results showed that TLR4 was extensively expressed in the renal tubules of DKD patients and db/db diabetic mice, which was positively related to the tubular interstitial damage score and urinary β-NAG levels. In diabetic mice, inhibition of TLR4 could reverse the decreased expression of PGC-1α, increased expression of cytochrome C and cleaved caspase-3, mitochondrial dysfunction and deformation, increased accumulation of ROS, and activation of tubular cell apoptosis. In vitro, inhibition of TLR4 or NF-κB showed consistent results. PGC-1α overexpression could reverse the mitochondrial dysfunction, increased cleaved caspase-3, and apoptosis in HK-2 cells treated with HG. Data indicated that the TLR4/NF-κB signaling pathway might be the upstream pathway of PGC-1α and promote the tubular damage of DKD by modulating the mitochondria-related oxidative damage and apoptosis.

The potential mechanism of mitochondrial dysfunction in septic cardiomyopathy

Septic cardiomyopathy is one of the most serious complications of sepsis or septic shock. Basic and clinical research has studied the mechanism of cardiac dysfunction for more than five decades. It has become clear that myocardial depression is not related to hypoperfusion. As the heart is highly dependent on abundant adenosine triphosphate (ATP) levels to maintain its contraction and diastolic function, impaired mitochondrial function is lethally detrimental to the heart. Research has shown that mitochondria play an important role in organ damage during sepsis. The mitochondria-related mechanisms in septic cardiomyopathy have been discussed in terms of restoring mitochondrial function. Mitochondrial uncoupling proteins located in the mitochondrial inner membrane can promote proton leakage across the mitochondrial inner membrane. Recent studies have demonstrated that proton leakage is the essential regulator of mitochondrial membrane potential and the generation of reactive oxygen species (ROS) and ATP. Other mechanisms involved in septic cardiomyopathy include mitochondrial ROS production and oxidative stress, mitochondria Ca²⁺ handling, mitochondrial DNA in sepsis, mitochondrial fission and fusion, mitochondrial biogenesis, mitochondrial gene regulation and mitochondria autophagy. This review will provide an overview of recent insights into the factors contributing to septic cardiomyopathy.

Sirtuin 1 activation enhances the PGC-1α/mitochondrial antioxidant system pathway in status epilepticus

Sirtuin 1 (SIRT1) regulates numerous neuronal processes, including metabolism, antioxidation and aging, through activation of peroxisome proliferator-activated receptor coactivator 1-α (PGC-1α), an upstream regulator of mitochondrial biogenesis and function. However, the role of SIRT1 in the oxidative stress induced by seizures has yet to be elucidated. The present study aimed to investigate whether SIRT1 was involved in the activation of the PGC-1α/mitochondrial antioxidant system following status epilepticus (SE) in rats. The data demonstrated that SIRT1 expression and activity were enhanced in the rat hippocampus following SE. SIRT1 inhibition effectively blocked the SE-associated increase in PGC-1α and mitochondrial antioxidant enzymes, including superoxide dismutase 2 (SOD2) and uncoupling protein 2 (UCP2). Additionally, it was also demonstrated that the activation of SIRT1 enhanced mitochondrial electron transport chain complex I activity and increased ATP content. In conclusion, the present results suggest that SIRT1 activation may alleviate mitochondrial oxidative stress induced by seizures partially via PGC-1α signaling.

Role of propolis on biochemical parameters in kidney and heart tissues against L-NAME induced oxidative injury in rats

Nitric oxide (NO), produced by endothelial NO synthase, is recognised as a central antiinflammatory and antiatherogenic principle in the vasculature. Epidemiological and clinical studies have demonstrated that a growing list of natural products, as components of the daily diet or phytomedical preparations, may improve vascular function by enhancing NO bioavailability. In this article, we investigated antioxidant effects of propolis on biochemical parameters in kidney and heart tissues of acute NO synthase inhibited rats by Nω-nitro-l-arginine methyl ester (l-NAME). There was increase (p < 0.001) in the activities of catalase and malondialdehyde levels in the l-NAME treatment groups when compared with control rats, but NO levels were decreased in both kidney and heart tissues. There were statistically significant changes (p < 0.001) in these parameters of l-NAME + propolis treated rats as compared with l-NAME-treated group. In summary, propolis may influence endothelial NO production.

Function of the master energy regulator adenosine monophosphate-activated protein kinase in stroke

Adenosine monophosphate-activated protein kinase (AMPK) is an evolutionarily conserved signaling molecule that is emerging as one of the most important energy sensors in the body. AMPK monitors cellular energy status and is activated via phosphorylation when energy stores are low. This allows for maintenance of energy homeostasis by promoting catabolic pathways for ATP production and limiting processes that consume ATP. Growing number of stimuli have been shown to activate AMPK, and AMPK has been implicated in many diverse biological processes, including cell polarity, autophagy, and senescence. The effect of AMPK activation and its biological functions are extremely diverse and depend on both the overall energy "milieu" and the location and duration of activation. AMPK has tissue- and isoform-specific functions in the brain vs. periphery. These functions and the pathways activated also appear to differ by cell location (hypothalamus vs. cortex), cell type (astrocyte vs. neuron), and duration of exposure. Short bursts of AMPK activation have been found to be involved in ischemic preconditioning and neuronal survival; however, prolonged AMPK activity during ischemia leads to neuronal cell death. AMPK may also underlie some of the beneficial effects of hypothermia, a potential therapy for ischemic brain injury. This review discusses the role of AMPK in ischemic stroke, a condition of severe energy depletion.