Selenium Protects ARPE-19 and ACBRI 181 Cells against High Glucose-Induced Oxidative Stress.

Diabetic retinopathy (DR), a complication of diabetes mellitus (DM), can cause severe visual loss. The retinal pigment epithelium (RPE) plays a crucial role in retinal physiology but is vulnerable to oxidative damage. We investigated the protective effects of selenium (Se) on retinal pigment epithelium (ARPE-19) and primary human retinal microvascular endothelial (ACBRI 181) cells against high glucose (HG)-induced oxidative stress and apoptotic cascade. To achieve this objective, we utilized varying concentrations of D-glucose (ranging from 5 to 80 mM) to induce the HG model. HG-induced oxidative stress in ARPE-19 and ACBRI 181 cells and the apoptotic cascade were evaluated by determining Ca2+ overload, mitochondrial membrane depolarization, caspase-3/-9 activation, intracellular reactive oxygen species (ROS), lipid peroxidation (LP), glutathione (GSH), glutathione peroxidase (GSH-Px), vascular endothelial growth factor (VEGF) and apoptosis levels. A cell viability assay utilizing MTT was conducted to ascertain the optimal concentration of Se to be employed. The quantification of MTT, ROS, VEGF levels, and caspase-3 and -9 activation was accomplished using a plate reader. To quantitatively assess LP and GSH levels, GSH-Px activities were utilized by spectrophotometer and apoptosis, mitochondrial membrane depolarization, and the release of Ca2+ from intracellular stores were evaluated by spectrofluorometer. Our investigation revealed a significant augmentation in oxidative stress induced by HG, leading to cellular damage through modulation of mitochondrial membrane potential, ROS levels, and intracellular Ca2+ release. Incubation with Se resulted in a notable reduction in ROS production induced by HG, as well as a reduction in apoptosis and the activation of caspase-3 and -9. Additionally, Se incubation led to decreased levels of VEGF and LP while concurrently increasing levels of GSH and GSH-Px. The findings from this study strongly suggest that Se exerts a protective effect on ARPE-19 and ACBRI 181 cells against HG-induced oxidative stress and apoptosis. This protective mechanism is partially mediated through the intracellular Ca2+ signaling pathway.

Chlorophyll Pigments of Olive Leaves and Green Tea Extracts Differentially Affect Their Antioxidant and Anticancer Properties.

Plant-based extracts possess biological potential due to their high content of phytochemicals. Nevertheless, photosynthetic pigments (e.g., chlorophylls) that are also present in plant extracts could produce undesirable pro-oxidant activity that might cause a negative impact on their eventual application. Herein, the phenolic content of olive leaf (OLE) and green tea (GTE) extracts was assayed, and their antioxidant and anticancer activities were evaluated before and after the removal of chlorophylls. Regarding phenolic content, OLE was rich in hydroxytyrosol, tyrosol as well as oleuropein, whereas the main compounds present in GTE were gallocatechin, epigallocatechin (EGC), epigallocatechin gallate (EGCG), gallocatechin gallate, and caffeine. Interestingly, fresh extracts' antioxidant ability was dependent on phenolic compounds; however, the elimination of chlorophyll compounds did not modify the antioxidant activity of extracts. In addition, both OLE and GTE had high cytotoxicity against HL-60 leukemic cell line. Of note, the removal of chlorophyll pigments remarkably reduced the cytotoxic effect in both cases. Therefore, our findings emphasize the remarkable antioxidant and anticancer potential of OLE and GTE and suggest that chlorophylls are of paramount importance for the tumor-killing ability of such plant-derived extracts.

The efficiency of oxerutin on apoptosis and kidney function in rats with renal ischemia reperfusion injury.

BACKGROUND: Background: Renal ischemia-reperfusion injury (RIRI) is the most frequent cause of acute renal failure in clinical conditions such as trauma and shock as well as renal surgeries. Oxerutin is a member of the flavonoid family and possesses antioxidant properties. The aim of this study was to investigate whether oxerutin has protective effects on RIRI. METHODS: Twenty-eight male Wistar albino rats were randomly divided into three groups: sham control group (n=8), RIRI group (n=10), and RIRI + oxerutin group (n=10). RIRI was achieved by clamping the left renal artery for 30 min, followed 1-h reperfusion period. Thereafter, blood samples and left kidney tissue samples were taken for histopathological and biochemical examination. Blood urea nitrogen (BUN), urea, creatinine, and cystatin C levels, which are indicators of kidney function, as well as tumor necrosis factor-alpha, which is an indicator of inflammation were analyzed in blood samples. Total antioxidant status and total oxidant status (TOS), which are indicators of oxidative stress were analyzed on renal tissues. The apoptotic index, an indicator of kidney damage, as well as histopathological changes were evaluated on renal tissues. RESULTS: The apoptotic index, TOS, tumor necrosis factor-alpha, BUN, and urea levels were lower in the RIRI + oxerutin group than in the RIRI group (p<0.05). The results demonstrated that the histopathological and biochemical properties of oxerutin protected rats from RIRI. CONCLUSION: The findings obtained in this study show that prophylactic administration of oxerutin has protective effects on apoptosis and renal failure caused by RIRI. Therefore, oxerutin can be used as an effective prophylactic agent in the treatment of RIRI.

Protective effects of caffeic acid phenethyl ester on the heart in experimental periodontitis against oxidative stress in rats.

BACKGROUND: Caffeic acid phenethyl ester (CAPE) may be considered as alternative treatment for periodontitis and benefit the heart by way of its ameliorative effects. OBJECTIVES: The aim of the study was to evaluate the effects of CAPE on cytokine levels and the oxidative status in the serum and heart tissue in a rat model of periodontitis. MATERIAL AND METHODS: Experimental animals were randomly assigned to 3 groups: control group (C; n = 8); periodontitis group (P; n = 10); and periodontitis + CAPE group (PC; n = 10). Caffeic acid phenethyl ester, at a dose of 10 µmol/kg/day, was administered by intraperitoneal injection over a 14-day period. Interleukin (IL)-1ß, IL­10 and tumor necrosis factor-alpha (TNF-α) were assessed in the serum. Glutathione (GSH), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) were assessed in both the serum and the heart tissue homogenate. RESULTS: Increased IL­1ß, IL­10 and TNF-α serum levels were observed in the P group (p < 0.05). Caffeic acid phenethyl ester significantly decreased alveolar bone loss (ABL) and cytokine levels in the PC group (p < 0.05). Malondialdehyde, one of the strongest oxidants, was significantly decreased in the PC group as compared to the P group (p < 0.05). In both the serum and the heart tissue homogenate there were no differences in MDA levels between the PC and C groups. Furthermore, CAPE significantly increased GSH and GSH-Px levels in the serum and heart tissue (p < 0.05). CONCLUSIONS: Caffeic acid phenethyl ester has beneficial effects on the tissues affected by periodontitis.

Protective effects of melatonin and memantine in human retinal pigment epithelium (ARPE-19) cells against 2-ethylpyridine-induced oxidative stress: implications for age-related macular degeneration.

PURPOSE: To investigate the possible protective effects of melatonin and memantine (MMT) against 2-ethylpyridine (2-EP)-induced oxidative stress and mitochondrial dysfunction in human RPE (ARPE-19) cells in vitro. MATERIALS AND METHODS: The ARPE-19 cells were divided into seven groups. Oxidative stress was triggered by incubating the ARPE-19 cells with 30 µM of 2-EP for 24 h. Then, 200 µM of melatonin was administered over three days and 20 µM of MMT over six hours prior to the experiment. The effects of melatonin and MMT on the intracellular calcium release mechanism, reactive oxygen species production, caspase-3 and caspase-9 activities, as well as vascular endothelial growth factor levels were measured. RESULTS: Melatonin and MMT were found to significantly decrease apoptosis levels. The intracellular calcium release was regulated by both melatonin and MMT. Further, melatonin and MMT significantly decreased both caspase-3 and caspase-9 activities, as well as pro-caspase and poly(ADP-ribose) polymerase expression, in ARPE-19 cells. Moreover, melatonin significantly increased the protective effect of MMT. The combination of melatonin and MMT significantly decreased 2-EP-induced oxidative toxicity and apoptosis by inhibiting the intracellular reactive oxygen species production and mitochondrial depolarization levels. CONCLUSIONS: These notable findings are the first to demonstrate the synergistic protective effects of melatonin and MMT against 2-EP-induced oxidative stress in ARPE-19 cells.

Is caffeic acid phenethyl ester more protective than doxycycline in experimental periodontitis?

BACKGROUND AND OBJECTIVES: Host modulation therapies (anti-inflammatory drugs, bone-stimulating agents, anti-proteinase etc.) target the inhibition or stabilization of tissue breakdown. The aim of the present study was to evaluate the effects of caffeic acid phenethyl ester (CAPE) and/or low dose doxycycline (LDD) administrations on alveolar bone loss (ABL), serum cytokines and gingival apoptosis, as well as the levels of oxidants and anti-oxidants in rats with ligature-induced periodontitis. MATERIAL AND METHODS: The animals were randomly divided into five groups: Group C (periodontally healthy), Group PC (Periodontitis+CAPE), Group PD (Periodontitis+LDD), Group PCD (Periodontitis+CAPE+LDD), Group P (Periodontitis). Experimental periodontitis was induced for 14days. Levels of ABL, and the serum cytokines, interleukin (IL)-1 ß, IL-6, tumor necrosis factor-α (TNF-α) and IL-10 were assessed as were the levels of the oxidants and anti-oxidants, malondialdehyde (MDA), glutathione (GSH) and glutathione peroxidase (GSH-Px), and levels of gingival apoptosis. RESULTS: The lowest ABL levels was evident in the PC group, among the experimental groups. There was also less inflammatory infiltration in the PC group than the PD group. IL-1ß, IL-6, and IL-10 were lower in the PC group and higher in the P group in comparison to the levels in the other experiment groups. TNF-α levels in the PD group were higher than levels in the PC and PCD groups. The PC and PCD groups did not differ from the C group in regard to MDA levels. The highest GSH-Px level was found in the PC group. Gingival apoptosis in the PC group was not only lower than the PD and PCD groups, but also lower than in the C group. CONCLUSION: The present study suggests that CAPE has more anti-inflammatory, anti-oxidant and anti-apoptotic effects than LDD, with no additive benefits of a CAPE+LDD combination being evident in rats with periodontitis.

Effect of a corticosteroid (triamcinolone) and chlorhexidine on chemotherapy-induced oxidative stress in the buccal mucosa of rats.

Oral mucositis manifests as erythematous and ulcerative lesions of the oral mucosa. Among its various causes, cancer treatment (e.g., chemotherapy with or without radiation therapy) is one of the more well known. It has been widely mentioned that oxidative stress parameters such as lipid peroxidation levels increase during the cancer process. Glutathione is one of the major intracellular enzymes used to detoxify oxidant molecules; it exists in both a reduced and oxidized state. Reduced glutathione is used as a substrate to synthesize glutathione peroxidase. We conducted a study to investigate and compare the effects of triamcinolone (a synthetic steroid) and chlorhexidine (a chemical antiseptic) on 5-fluorouracil (5-FU; a chemotherapeutic agent)-induced oral mucositis in the buccal mucosa of 36 rats. Oral mucositis was induced through a combination of 5-FU treatment and mild abrasion of the cheek pouch with a wire brush. The rats were treated with one of four regimens: saline placebo (group I), 5-FU only (group II), 5-FU plus triamcinolone (group III), and 5-FU plus chlorhexidine (group IV). Three rats in the triamcinolone group died of unknown causes on days 7 and 8, and 3 rats in the chlorhexidine group died on days 7 and 9. On day 9, the remaining 30 rats were sacrificed and examined. Buccal mucosa lipid peroxidation levels were significantly higher in the 5-FU-only group than in the control group and significantly higher in the control group than in the triamcinolone group (p < 0.05 for both). Levels of reduced glutathione were significantly lower in the 5-FU-only group than in both the triamcinolone group and the chlorhexidine group (p < 0.05). Glutathione peroxidase activity was significantly higher in the triamcinolone group than in the 5-FU-only group (p < 0.01). Histopathologic analysis revealed that treatment with triamcinolone significantly reduced 5-FU-induced inflammatory cell infiltration and ulceration (p < 0.001); no such reduction was seen with chlorhexidine. In conclusion, we observed that triamcinolone and chlorhexidine treatment modulated chemotherapy-induced oxidative injury in rat oral mucositis. However, only triamcinolone histopathologically ameliorated 5-FU-induced oral mucositis. These findings suggest that triamcinolone is a useful agent for the management of experimental oxidative injury and oral mucositis caused by 5-FU chemotherapy.

The Importance of Melatonin and Mitochondria Interaction in Mood Disorders and Schizophrenia: A Current Assessment.

Mitochondria play a critical role in regulating cellular functions, such as redox signaling, calcium homeostasis, and apoptosis. Also, mitochondria are crucial for neurogenesis and neuronal functions. Melatonin is an indole analog hormone, which is generally produced by the pineal gland. It plays a vital role in circadian rhythm and act as a powerful antioxidant by scavenging free radicals, immunomodulators, and anticancer agents. Schizophrenia and mood disorders are the two major psychiatric disorders. Disturbances of sleep and circadian rhythms are well-known symptoms of schizophrenia and mood disorders (bipolar disorder, major depression). Since melatonin has a regulator effect on circadian rhythm and sleep quality, it has a close interaction with schizophrenia and mood disorders. Herein, we aimed to summarize the effects of melatonin on mitochondrial activity in schizophrenia and mood disorders.

Curcumin inhibits apoptosis by regulating intracellular calcium release, reactive oxygen species and mitochondrial depolarization levels in SH-SY5Y neuronal cells.

Neurological diseases such as Alzheimer's and Parkinson's diseases are incurable progressive neurological disorders caused by the degeneration of neuronal cells and characterized by motor and non-motor symptoms. Curcumin, a turmeric product, is an anti-inflammatory agent and an effective reactive oxygen and nitrogen species scavenging molecule. Hydrogen peroxide (H2O2) is the main source of oxidative stress, which is claimed to be the major source of neurological disorders. Hence, in this study we aimed to investigate the effect of curcumin on Ca(2+) signaling, oxidative stress parameters, mitochondrial depolarization levels and caspase-3 and -9 activities that are induced by the H2O2 model of oxidative stress in SH-SY5Y neuronal cells. SH-SY5Y neuronal cells were divided into four groups namely, the control, curcumin, H2O2, and curcumin + H2O2 groups. The dose and duration of curcumin and H2O2 were determined from published data. The cells in the curcumin, H2O2, and curcumin + H2O2 groups were incubated for 24 h with 5 µM curcumin and 100 µM H2O2. Lipid peroxidation and cytosolic free Ca(2+) concentrations were higher in the H2O2 group than in the control group; however, their levels were lower in the curcumin and curcumin + H2O2 groups than in the H2O2 group alone. Reduced glutathione (GSH) and glutathione peroxidase (GSH-Px) values were lower in the H2O2 group although they were higher in the curcumin and curcumin + H2O2 groups than in the H2O2 group. Caspase-3 activity was lower in the curcumin group than in the H2O2 group. In conclusion, curcumin strongly induced modulator effects on oxidative stress, intracellular Ca(2+) levels, and the caspase-3 and -9 values in an experimental oxidative stress model in SH-SY5Y cells.

Effects of pentoxifylline and alpha lipoic acid on methotrexate-induced damage in liver and kidney of rats.

The aim of the current study was to investigate the probable protective effects of Pentoxifylline (PTX) and Alpha Lipoic Acid (ALA), which display anti-oxidative efficacy against hepatotoxicity and nephrotoxicity, those being the major side effects of Methotrexate (MTX). Rats were divided into four groups: a control group; MTX (20mg/kg/day) group; MTX+PTX (20mg/kg/day+50mg/kg/day) group; and an MTX+ALA (20mg/kg/day+100mg/kg/day) group. At the end of the experiment, biochemical, histochemical and immunohistochemical analyses were performed on liver and kidney tissues of rats. We determined Glutathione Peroxidase (GSH-Px), Superoxide Dismutase (SOD), Catalase (CAT), Malondialdehyde (MDA), Nitric Oxide (NO) and Xanthine Oxidase (XO) levels in the liver and kidney. Moreover, Gamma Glutamyl Transferase (GGT), Direct Bilirubin (DBil), Blood Urea Nitrogen (BUN), and urea levels were measured in the serum. The histochemical evaluation revealed a significant decrease in MTX caused damage in the PTX- and ALA-treated groups (especially in ALA group). On the other hand, the immune staining of iNOS and TNF-α were observed most densely in the MTX group, while the density decreased in the PTX- and ALA-administered groups. We determined increased GGT, BUN, urea and levels of CAT, MDA, NO, and XO values in both groups, while GSH-Px (an increase in liver tissue) and DBil levels were decreased in the group that received MTX. However, we determined decreased SOD levels in liver tissue. In the PTX and ALA groups, the levels of GGT, BUN and urea as well as the levels of CAT, MDA, NO and XO decreased (SOD increased in the liver tissue), and the levels of GSH-Px and DBil increased. In conclusion, it can be stated that, although ALA is more effective in preventing the toxic effects of MTX on the liver and kidney, PTX also has a preventive effect. As a result, we can readily suggest that ALA and PTX can have protective effects by decreasing MDA, NO, BUN and urea values as antioxidants against MTX-induced damage in liver and kidney of rats.

Riboflavin and vitamin E increase brain calcium and antioxidants, and microsomal calcium-ATP-ase values in rat headache models induced by glyceryl trinitrate.

The essential use of riboflavin is the prevention of migraine headaches, although its effect on migraines is considered to be associated with the increased mitochondrial energy metabolism. Oxidative stress is also important in migraine pathophysiology. Vitamin E is a strong antioxidant in nature and its analgesic effect is not completely clear in migraines. The current study aimed to investigate the effects of glyceryl trinitrate (GTN)-sourced exogen nitric oxide (NO), in particular, and also riboflavin and/or vitamin E on involved in the headache model induced via GTN-sourced exogen NO on oxidative stress, total brain calcium levels, and microsomal membrane Ca(2+)-ATPase levels. GTN infusion is a reliable method to provoke migraine-like headaches in experimental animals and humans. GTN resulted in a significant increase in brain cortex and microsomal lipid peroxidation levels although brain calcium, vitamin A, vitamin C, and vitamin E, and brain microsomal-reduced glutathione (GSH), glutathione peroxidase (GSH-Px), and plasma-membrane Ca(2+)-ATPase values decreased through GTN. The lipid peroxidation, GSH, vitamin A, ß-carotene, vitamin C, and vitamin E, and calcium concentrations, GSH-Px, and the Ca(2+)-ATPase activities were increased both by riboflavin and vitamin E treatments. Brain calcium and vitamin A concentrations increased through riboflavin only. In conclusion, riboflavin and vitamin E had a protective effect on the GTN-induced brain injury by inhibiting free radical production, regulation of calcium-dependent processes, and supporting the antioxidant redox system. However, the effects of vitamin E on the values seem more important than in riboflavin.

Protective effects of riboflavin and selenium on brain microsomal Ca2+-ATPase and oxidative damage caused by glyceryl trinitrate in a rat headache model.

Migraine headaches are considered to be associated with increased mitochondrial energy metabolism. Mitochondrial oxidative stress is also important in migraine headache pathophysiology although riboflavin and selenium (Se) induced a modulator role on mitochondrial oxidative stress in the brain. The current study aimed to determine the effects of Se with/without riboflavin on the microsomal membrane Ca(2+)-ATPase (MMCA), lipid peroxidation, antioxidant, and electroencephalography (EEG) values in glyceryl trinitrate (GTN)-induced brain injury rats. Thirty-two rats were randomly divided into four groups. The first group was used as the control, and the second group was the GTN group. Se and Se plus oral riboflavin were administered to rats constituting the third and fourth groups for 10 days prior to GTN administration. The second, third, and fourth groups received GTN to induce headache. Ten hours after the administration of GTN, the EEG records and brain cortex samples were obtained for all groups. Brain cortex microsomes were obtained from the brain samples. The brain and microsomal lipid peroxidation levels were higher in the GTN group compared to the control group, whereas they were decreased by selenium and selenium + riboflavin treatments. Vitamin A, vitamin C, vitamin E, and reduced glutathione (GSH) concentrations of the brain and MMCA, GSH and glutathione peroxidase values of microsomes were decreased by the GTN administration, although the values and ß-carotene concentrations were increased by Se and Se + riboflavin treatments. There was no significant change in EEG records of the four groups. In conclusion, Se with/without riboflavin administration protected against GTN-induced brain oxidative toxicity by inhibiting free radicals and the modulation of MMCA activity and supporting the antioxidant redox system.

Paliperidone regulates intracellular redox system in rat brain: Role of purine mechanism.

OBJECTIVE: The treatment of schizophrenia is multifactorial, with antipsychotic medications comprising a major part of treatment. Paliperidone is a newly commercialized antipsychotic whose formulation includes the principal active metabolite risperidone, 9-hydroxyrisperidone. Ever since the relationship between schizophrenia and oxidative stress was first demonstrated, many studies have been conducted in order to probe the potential protective effects of antipsychotic drugs on the oxidant-antioxidant system and lipid peroxidation. The basic aim of this study is to determine the effects of the newly marketed drug paliperidone on the activities of the enzymes adenosine deaminase (ADA), xanthine oxidase (XO), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) as well as on malondialdehyde (MDA) and nitric oxide (NO) levels in rat brain tissues. METHODS: Twenty male Sprague-Dawley rats were used for the study, which were divided into two equal groups. The first was the control group (n = 10) and the second was the paliperidone group (n = 10). Saline was administered once daily for 14 days in the control group. In the paliperidone group, paliperidone was administered once daily with a dose of 1 mg/kg for 14 days. All rats were sacrificed at the end of the fourteenth day. Brain samples were collected and then analyzed. RESULTS: Our results demonstrated that paliperidone significantly decreased the activities of ADA (P = 0.015), XO (P = 0.0001), and CAT (P = 0.004) while insignificantly increasing the activity of SOD (P = 0.49), MDA (P = 0.71), and NO (P = 0.26) levels in rat brain tissues. In addition, paliperidone insignificantly decreased the activity of GSH-Px (P = 0.30) compared to the control group in rat brain tissues. DISCUSSION: In conclusion, the data obtained in this study suggest that paliperidone can positively alter antioxidant status and, accordingly, can offer positive outcomes in the treatment of schizophrenia by reducing activity in the enzymes ADA and XO, which are associated with purine metabolism. We believe that such a comprehensive approach used with other antipsychotic drugs warrants further study.

Elevated hydrostatic pressures induce apoptosis and oxidative stress through mitochondrial membrane depolarization in PC12 neuronal cells: A cell culture model of glaucoma.

BACKGROUND: Despite the importance of oxidative stress and apoptosis through mitochondrial depolarization in neurodegenerative diseases, their roles in etiology of glaucoma are poorly understood. We aimed to investigate whether oxidative stress and apoptosis formation are altered in rat pheochromocytoma-derived cell line-12 (PC12) neuronal cell cultures exposed to elevated different hydrostatic pressures as a cell culture model of glaucoma. MATERIALS: Cultured PC12 cells were subjected to 0, 15 and 70 mmHg hydrostatic pressure for 1 and 24 h. Then, the following values were analyzed: (a) cell viability; (b) lipid peroxidation and intracellular reactive oxygen species production; (c) mitochondrial membrane depolarization; (d) cell apoptosis; (e) caspase-3 and caspase-9 activities; (f) reduced glutathione (GSH) and glutathione peroxidase (GSH-Px). RESULTS: The hydrostatic pressures (15 and 70 mmHg) increased oxidative cell damage through a decrease of GSH and GSH-Px values, and increasing mitochondrial membrane potential. Additionally, 70 mmHg hydrostatic pressure for 24 h indicated highest apoptotic effects, as demonstrated by plate reader analyses of apoptosis, caspase-3 and -9 values. CONCLUSION: The present data indicated oxidative stress, apoptosis and mitochondrial changes in PC12 cell line during different hydrostatic pressure as a cell culture model of glaucoma. This findings support the view that mitochondrial oxidative injury contributes early to glaucomatous optic neuropathy.

Agomelatine and duloxetine synergistically modulates apoptotic pathway by inhibiting oxidative stress triggered intracellular calcium entry in neuronal PC12 cells: role of TRPM2 and voltage-gated calcium channels.

Calcium ion (Ca(2+)) is one of the universal second messengers, which acts in a wide range of cellular processes. Results of recent studies indicated that ROS generated by depression leads to loss of endoplasmic reticulum-Ca(2+) homeostasis, oxidative stress, and apoptosis. Agomelatine and duloxetine are novel antidepressant and antioxidant drugs and may reduce oxidative stress, apoptosis, and Ca(2+) entry through TRPM2 and voltage-gated calcium channels. We tested the effects of agomelatine, duloxetine, and their combination on oxidative stress, Ca(2+) influx, mitochondrial depolarization, apoptosis, and caspase values in the PC-12 neuronal cells. PC-12 neuronal cells were exposed in cell culture and exposed to appropriate non-toxic concentrations and incubation times for agomelatine were determined in the neurons by assessing cell viability. Then PC-12 cells were incubated with agomelatine and duloxetine for 24 h. Treatment of cultured PC-12 cells with agomelatine, duloxetine, and their combination results in a protection on apoptosis, caspase-3, caspase-9, mitochondrial membrane depolarization, cytosolic ROS production, glutathione peroxidase, reduced glutathione, and lipid peroxidation, values. Ca(2+) entry through non-specific TRPM2 channel blocker (2-APB) and voltage-gated Ca(2+) channel blockers (verapamil and diltiazem) was modulated by agomelatine and duloxetine. However, effects of duloxetine on the Ca(2+) entry through TRPM2 channels were higher than in agomelatine. Results of current study suggest that the agomelatine and duloxetine are useful against apoptotic cell death and oxidative stress in PC-12 cells, which seem to be dependent on mitochondrial damage and increased levels of intracellular Ca(2+) through activation of TRPM2 and voltage-gated Ca(2+) channels.

Alpha lipoic acid attenuates inflammatory response during extracorporeal circulation.

AIM: Extracorporeal circulation (ECC) of blood during cardiopulmonary surgery has been shown to stimulate various proinflammatory molecules such as cytokines and chemokines. The biochemical oxidation/reduction pathways of α-lipoic acid suggest that it may have antioxidant properties. METHODS: In this study we aimed to evaluate only patients with coronary heart disease and those planned for coronary artery bypass graft operation. Blood samples were obtained from the patients before the operation (P1) and one (P2), four (P3), 24 (P4) and 48 hours (P5) after administration of α-lipoic acid (LA). The patients were divided into two groups, control and LA treatment group. Levels of interleukin- 6 (IL-6) and -8 (IL-8), complement 3 (C3) and 4 (C4), anti-streptolysin (ASO), C-reactive protein (CRP) and haptoglobin were assessed in the blood samples. RESULTS: Cytokine IL-6 and IL-8 levels were significantly higher after surgery. Compared with the control groups, LA significantly decreased IL-6 and IL-8 levels in a time-dependent manner. CRP levels did not show significant variation in the first three time periods. CRP levels were higher after surgery, especially in the later periods. These results demonstrate that CRP formation depends on cytokine release. C3 and C4 levels were significantly higher after surgery than in the pre-operative period. LA treatment decreased C3 and C4 levels. Therefore, LA administration may be useful for the treatment of diseases and processes where excessive cytokine release could cause oxidative damage. CONCLUSION: Our findings suggest a possible benefit of using LA during cardiac surgery to reduce cytokine levels.

Role of TRPM2 cation channels in dorsal root ganglion of rats after experimental spinal cord injury.

INTRODUCTION: We sought to determine the contribution of oxidative stress-dependent activation of TRPM2 and L-type voltage-gated Ca(2+) channels (VGCC) in dorsal root ganglion (DRG) neurons of rats after spinal cord injury (SCI). METHODS: The rats were divided into 4 groups: control; sham control; SCI; and SCI+nimodipine groups. The neurons of the SCI groups were also incubated with non-specific TRPM2 channel blockers, 2-aminoethoxydiphenylborate (2-APB) and N-(p-amylcinnamoyl)anthranilic acid (ACA), before H2 O2 stimulation. RESULTS: The [Ca(2+) ]i concentrations were higher in the SCI group than in the control groups, although their concentrations were decreased by nimodipine and 2-APB. The H2 O2 -induced TRPM2 current densities in patch-clamp experiments were decreased by ACA and 2-APB incubation. In the nimodipine group, the TRPM2 channels of neurons were not activated by H2 O2 or cumene hydroperoxide. CONCLUSIONS: Increased Ca(2+) influx and currents in DRG neurons after spinal injury indicated TRPM2 and voltage-gated Ca(2+) channel activation.

Intracellular Ca2+ and antioxidant values induced positive effect on fertilisation ratio and oocyte quality of granulosa cells in patients undergoing in vitro fertilisation.

Oxidative stress is important for promoting oocyte maturation and ovulation within the follicle through calcium ion (Ca(2+)) influx. The relationship between antioxidant and cytosolic Ca(2+) levels and oocyte quality and fertilisation rate in the granulosa cells of patients undergoing in vitro fertilisation was investigated. Granulosa cells were collected from 33 patients. Cytosolic free Ca(2+) ([Ca(2+)]i) concentration, lipid peroxidation, reduced glutathione, glutathione peroxidase and oocyte quality were measured in the granulosa cells. The relationship between two drug protocols was also examined (gonadotrophin-releasing hormone antagonist and agonist protocols) and the same parameters investigated. The [Ca(2+)]i concentration (P<0.001), glutathione (P<0.05) and oocyte quality (P<0.001) values were significantly higher in the fertilised group than in the non-fertilised group, although glutathione peroxidase activity was significantly (P<0.05) higher in the non-fertilised group than in the fertilised group. The [Ca(2+)]i concentrations were also higher (P<0.001) in the good-quality oocyte groups than in the poor-quality oocyte group. There was no correlation between the two drug protocols and investigated parameters. In conclusion, it was observed that high glutathione and cytosolic Ca(2+) concentrations in granulosa cells of patients undergoing in vitro fertilisation tended to increase the fertilisation potential of oocytes.

Effects of selenium and topiramate on cytosolic Ca(2+) influx and oxidative stress in neuronal PC12 cells.

It has been widely suggested that selenium (Se) deficiency play an important role in the pathophysiology of epilepsy. It has been reported that Se provides protection against the neuronal damage in patients and animals with epilepsy by restoring the antioxidant defense mechanism. The neuroprotective effects of topiramate (TPM) have been reported in several studies but the putative mechanism of action remains elusive. We investigated effects of Se and TPM in neuronal PC12 cell by evaluating Ca(2+) mobilization, lipid peroxidation and antioxidant levels. PC12 cells were divided into eight groups namely control, TPM, Se, H(2)O(2), TPM + H(2)O(2), Se + H(2)O(2), Se + TPM and Se + TPM + H(2)O(2). The toxic doses and times of H(2)O(2), TPM and Se were determined by cell viability assay which is used to evaluate cell viability. Cells were incubated with 0.01 mM TPM for 5 h and 500 nM Se for 10 h. Then, the cells were exposed to 0.1 mM H(2)O(2) for 10 h before analysis. The cells in all groups except control, TPM and Se were exposed to H(2)O(2) for 15 min before analysis. Cytosolic Ca(2+) release and lipid peroxidation levels were higher in H(2)O(2) group than in control, Se and TPM combination groups although their levels were decreased by incubation of Se and TPM combination. However, there is no difference on Ca(2+) release in TPM group. Glutathione peroxidase activity, reduced glutathione and vitamin C levels in the cells were lower in H(2)O(2) group than in control, Se and TPM groups although their values were higher in the cells incubated with Se and TPM groups than in H(2)O(2) groups. In conclusion, these results indicate that Se induced protective effects on oxidative stress in PC12 cells by modulating cytosolic Ca(2+) influx and antioxidant levels. TPM modulated also lipid peroxidation and glutathione and vitamin C concentrations in the cell system.

Zonisamide attenuates MPP+-induced oxidative toxicity through modulation of Ca2+ signaling and caspase-3 activity in neuronal PC12 cells.

Parkinson's disease is an incurable progressive neurological condition caused by a degeneration of dopamine-producing cells characterized by motor and non-motor symptoms. The major mechanisms of the antiepileptic actions of ZNS are inhibition of voltage-gated Na(+) channel, T-type voltage-sensitive Ca(2+) channel, Ca(2+)-induced Ca(2+) releasing system, and neuronal depolarization-induced glutamate release; and enhancement of release of inhibitory neurotransmitters; however, the detailed mechanism of antiparkinsonian effects of ZNS remains to be clarified. We aimed to investigate to the effect of ZNS on the oxidative stress, cell viability, Ca(2+) signaling, and caspase activity that induced by the MPP(+) model of Parkinson's in neuronal PC12 cells. Neuronal PC12 cells were divided into four groups namely, control, ZNS, MPP(+), and ZNS+MPP(+) groups. The dose and duration of ZNS and MPP(+) were determined according to cell viability (MTT) analysis which used to assess the cell viability. The cells in ZNS, MPP(+), and ZNS+MPP(+) groups were incubated for 5 h with 100 µM ZNS, 10 h with 100 µM MPP(+), and 10 h with ZNS and MPP(+), respectively. Lipid peroxidation and cytosolic free Ca(2+) concentrations were higher in the MPP(+) group than in control although their levels were lower in ZNS and the ZNS+MPP(+) groups than in control. Reduced glutathione and glutathione peroxidase values were lower in the MPP(+) group although they were higher in the ZNS and the ZNS+MPP(+) groups than in control. Caspase-3 activity was lower in the ZNS group than in the MPP(+) group. In conclusion, ZNS induced modulator effects on the oxidative stress, intracellular Ca(2+), and the caspase-3 values in an experimental model of Parkinson disease.