Anti-oxidative effect of lipoic Acid in spinal cord ischemia/reperfusion

The effect of saffron (Crocus sativus L.) on glycemia, lipid profile, and antioxidant status in patients with type-2 diabetes mellitus: A randomized placebo-controlled trial

In the current study, we aimed to investigate the effect of saffron supplementation on glycemic status, lipid profile, atherogenic indices, and oxidative status in patients with type-2 diabetes (T2DM). In a randomized, double-blind controlled trial, 70 patients were randomly allocated into two groups (n = 35, each) and received 100 mg/day of saffron or placebo for eight weeks. Dietary intake, weight, body mass index (BMI), waist and hip circumferences (WC and HC), waist to hip ratio (WHR), fasting blood sugar (FBS), hemoglobin A1c (HbA1c), insulin, and Homeostatic model assessment for insulin resistance (HOMA-IR), lipid profile, atherogenic indices, oxidative status, and liver enzymes were determined before and after the intervention. At the end of the eighth week, saffron intervention could significantly reduce FBS (7.57%), lipid profile (except high-density lipoprotein cholesterol [HDL-C]), atherogenic indices, and liver enzymes (p < .05). Moreover, saffron could improve oxidative status (nitric oxide [NO] and malondialdehyde [MDA] reduced by 26.29% and 16.35%, respectively). Catalase (CAT) concentration remained unchanged. Saffron supplementation may alleviate T2DM by improving glycemic status, lipid profile, liver enzymes, and oxidative status. Further investigation is necessary to assess possible side effects and confirm the positive effect of saffron as a complementary therapy in clinical recommendations for T2DM.

The effects of apigenin administration on the inhibition of inflammatory responses and oxidative stress in the lung injury models: a systematic review and meta-analysis of preclinical evidence

BACKGROUND/OBJECTIVE

Apigenin is a member of the flavonoid family that can regulate various biological processes, which is characterized as a treatment of different inflammatory disorders and pathological problems associated with oxidative stress (OS). Recent research has focused on apigenin immunomodulatory properties as a potential treatment for different types of lung injuries. This meta-analysis was designed to determine the impact of apigenin treatment on inflammatory markers and OS parameters in animal models of lung injuries.

METHODS

The comprehensive literature search was conducted using electronic databases such as Google Scholar, PubMed, Web of Science, Scopus, and Embase up to August 2021. To assess apigenin's effect on inflammatory mediators and OS biomarkers in lung injury animal models, we used the I² statistic to determine the heterogeneity. We then pooled data as standardized mean difference (SMD) with a 95% confidence interval (CI).

RESULTS

Our meta-analysis of the pooled data for inflammatory biomarkers demonstrated that the apigenin administration significantly decreased the NF-κB expression (SMD - 1.60, 95% CI [- 2.93 to - 0.26]; I² = 89.0%, p < 0.001), IL-1β (SMD - 4.30, 95% CI [- 6.24 to - 2.37]; I² = 67.3%, p = 0.047), IL-6 (SMD - 4.10, 95% CI [- 5.04 to - 3.16]; I² = 72.6%, p < 0.001), TNF-α (SMD - 3.74, 95% CI [- 4.67 to - 2.82]; I² = 84.1%, p < 0.001), and TNF-α gene expression (SMD - 3.44, 95% CI [- 4.44 to - 2.43]; I² = 0.0%, p = 0.622). This study also indicated the efficacy of apigenin in increasing the level of CAT (SMD 4.56, 95% CI [3.57 to 5.55]; I² = 15.3%, p = 3.15), GSH (SMD 5.12, 95% CI [3.53 to 6.70]; I² = 77.6%, p < 0.001), and SOD (SMD 3.45, 95% CI [2.50 to 4.40]; I² = 79.2%, p < 0.001), and decreasing the level of MDA (SMD - 3.87, 95% CI [- 5.25 to - 2.49]; I² = 80.3%, p < 0.001) and MPO (SMD - 4.02, 95% CI [- 5.64 to - 2.40]; I² = 88.9%, p < 0.001), TGF- β (SMD - 3.81, 95% CI [- 4.91 to - 2.70]; I² = 73.4%, p = 0.001) and W/D level (SMD - 3.22, 95% CI [- 4.47 to - 1.97]; I² = 82.1%, p < 0.001) than control groups.

CONCLUSION

Overall, our findings showed the immunomodulatory potential of apigenin as an alternative treatment for the suppression of inflammatory responses and OS in different types of lung injury diseases. Nevertheless, due to the paucity of clinical studies, reliable preclinical models, and clinical settings, evaluating the influence of apigenin on lung injury is required in the future. Before conducting large-scale clinical trials, detailed human pharmacokinetic studies are also needed to establish dosage ranges and determine the initial safety and tolerability of apigenin.

Effects of Lipoic Acid on Ischemia-Reperfusion Injury

Ischemia-reperfusion (I/R) injury often occurred in some pathologies and surgeries. I/R injury not only harmed to physiological functions of corresponding organ and tissue but also induced multiple tissue or organ dysfunctions (even these in distant locations). Although the reperfusion of blood attenuated I/R injury to a certain degree, the risk of secondary damages was difficult to be controlled and it even caused failures of these tissues and organs. Lipoic acid (LA), as an endogenous active substance and a functional agent in food, owns better safety and effects in our body (e.g., enhancing antioxidant activity, improving cognition and dementia, controlling weight, and preventing multiple sclerosis, diabetes complication, and cancer). The literature searching was conducted in PubMed, Embase, Cochrane Library, Web of Science, and SCOPUS from inception to 20 May 2021. It had showed that endogenous LA was exhausted in the process of I/R, which further aggravated I/R injury. Thus, supplements with LA timely (especially pretreatments) may be the prospective way to prevent I/R injury. Recently, studies had demonstrated that LA supplements significantly attenuated I/R injuries of many organs, though clinic investigations were short at present. Hence, it was urgent to summarize these progresses about the effects of LA on different I/R organs as well as the potential mechanisms, which would enlighten further investigations and prepare for clinic applications in the future.

The protective effect of alpha-lipoic acid on the expression of collagen IV, renal function, and oxidative stress induced by diazinon in the renal parenchyma of rat

Diazinon (DZN) is an organophosphate pesticide that is commonly used in agriculture worldwide, including in Iran, and unfortunately, it leads to a variety of negative effects on the environment, animals, and humans. Alpha-lipoic acid (ALA) is an antioxidant agent that acts via scavenging of oxygen-free radicals. Collagen IV is a component of the main base membrane structure and DZN may also affect the expression of this key protein. The aim of this study was to evaluate antioxidant properties of ALA on the expression of collagen IV, renal function, and oxidative stress induced by DZN in renal tissue. In this experimental study, 30 adult male Wistar rats were randomly divided into five groups (n = 6) including: the control group, DZN (40 mg/kg) group, ALA (100 mg/kg) group, ALA (100 mg/kg) + DZN (40 mg/kg) group, and sham group. On day 0 and after 6 weeks, the urine and blood samples were collected to measure glomerular filtration rate (GFR). After 6 weeks, the rats were anesthetized and the left kidney was used for immunohistochemistry study and the right kidney was used to evaluate the oxidative stress parameters. The results have shown that ALA significantly improved the biochemical parameters including superoxide dismutase, glutathione peroxidase, glutathione S-transferase, glutathione reductase, and GFR. In addition, ALA significantly prevented the expression of collagen IV that was changed by DZN administration in rats. We concluded that when exposed to DZN, depletion of antioxidant enzymes is accompanied by the induction of oxidative stress that might be beneficial in monitoring DZN toxicity and alpha-lipoic acid, as an antioxidant can overcome the toxicity induced by DZN in the kidney.

Metformin Activates the Protective Effects of the AMPK Pathway in Acute Lung Injury Caused by Paraquat Poisoning

Objective

To observe whether metformin (MET) plays a protective role in acute lung injury (ALI) induced by paraquat (PQ) poisoning in rats by activating the AMPK/NF-κB signaling pathway.

Methods

PQ exposure was used to construct a rat model of ALI and a model of acute type II alveolar epithelial cell (RLE-6TN) injury, and MET intervention was performed. Rat lung tissue samples were collected to evaluate pathological changes in rat lung tissue, the oxidation index, and inflammatory factors; cell viability was detected by CCK-8 assays, and the protein expression levels of phospho-AMPK and phospho-NF-κBp65 in rat lung tissue and RLE-6TN cells were observed by Western blotting.

Results

Compared with the PQ group, the MET treatment group showed significantly (1) reduced lung wet/dry ratio (W/D: 4.67 ± 0.31 vs. 5.45 ± 0.40, P < 0.001), (2) reduced pathological changes in lung tissue, (3) decreased MDA levels (nmol/mg prot: 2.70 ± 0.19 vs. 3.08 ± 0.15, P < 0.001) and increased SOD and GSH-Px activities (U/mg prot: 76.17 ± 5.22 vs. 45.23 ± 6.58, 30.40 ± 2.84 vs. 21.00 ± 3.20; all P < 0.001) in lung tissue homogenate, (4) reduced levels of IL-1β, IL-6, and TNF-α in lung tissue homogenates (pg/mL: 47.87 ± 5.06 vs. 66.77 ± 6.55; 93.03 ± 7.41 vs. 107.39 ± 9.81; 75.73 ± 6.08 vs. 89.12 ± 8.94; all P < 0.001), (5) increased activity of RLE-6TN cells (%: 0.69 ± 0.09, 0.76 ± 0.06, and 0.58 ± 0.03 vs. 0.50 ± 0.05; all P < 0.05), (6) decreased protein levels of phospho-NF-κBp65 in lung homogenates and RLE-6TN cells (p-NF-κB/NF-κB: 0.47 ± 0.09 vs. 0.81 ± 0.13; 0.26 ± 0.07 vs. 0.79 ± 0.13; all P < 0.01), and (7) upregulated protein expression of phospho-AMPK in lung homogenates and RLE-6TN cells (p-AMPK/AMPK: 0.88 ± 0.05 vs. 0.36 ± 0.12; 0.93 ± 0.03 vs. 0.56 ± 0.15; all P < 0.01). After the addition of the AMPK inhibitor Compound C (Com C), the protein expression levels of phospho-AMPK and phospho-NF-κBp65 returned to baseline.

Conclusion

MET can effectively alleviate ALI induced by paraquat poisoning and increase the viability of cells exposed to paraquat. The mechanism may be related to the activation of the AMPK/NF-κB pathway, downregulation of inflammatory mediators such as IL-6 and TNF-α, and upregulation of the SOD and GSH-Px oxidation index, and these effects can be inhibited by the AMPK inhibitor Com C.

Baicalein Protects Rats with Diabetic Cardiomyopathy Against Oxidative Stress and Inflammation Injury via Phosphatidylinositol 3-Kinase (PI3K)/AKT Pathway

Background

The aim of this study was to explore the effect of baicalein on diabetic cardiomyopathy (DCM) rats and the mechanisms involved, and to determine the theoretical basis for clinical anti-tumor therapy.

Material/Methods

DCM rat model was induced with a single injection of streptozotocin. Then, DCM rats were treated with baicalein alone or co-treated with baicalein and PI3K/Akt inhibitor. Myocardial pathological changes were detected by HE and Masson staining. The activities of SOD, GSH-Px, and MDA in myocardial tissue were measured by biochemical tests. The levels of TNF-α, IL-1β, and cTn-I were examined by ELISA. NADP+/NADPH ratio was measured with the NADP+/NADPH assay kit. RT-PCR was used to detect the levels of PI3K and Akt. The levels of Bax, Bcl-2, Caspase-3, GSK-3β, PI3K, and Akt were detected by Western blot.

Results

Baicalein could improve pathological injury. SOD and GSH-Px activity decreased while the level of MDA increased in myocardial tissue. Baicalein treatment enhanced SOD activity in a dose-dependent manner but markedly reduced MDA. Similar changes were observed in both serum inflammatory factors and the NADP+/NADPH ratio. After adding PI3K-Akt inhibitor, the levels of PI3K and Akt mRNA expression were significantly decreased, but were not significantly different from the DCM group. Levels of Bcl-2, PI3K, p-GSK-3β/GSK-3β, and p-Akt were decreased in the DCM group, while the levels of Bax and Caspase-3 were obviously increased.

Conclusions

Baicalein can protect DCM rats against damage from oxidative stress and inflammation in myocardial tissue, and PI3K/Akt signaling pathway may be involved to mediating these effects.

Protective Effects of Alpha-Lipoic Acid on Methotrexate-Induced Oxidative Lung Injury in Rats

OBJECTIVE

Oxidative stress is one of the major causes of methotrexate induced lung injury (MILI). Alpha-lipoic acid (ALA), which occurs naturally in human food, has antioxidative and anti-inflammatory activities. The aim of this study was to research the potential protective role of ALA on MILI in rats.

METHODS

Twenty one rats were randomly subdivided into three groups: control (group I), methotrexate (MTX) treated (group II), and MTX+ALA treated (group III). Lung injury was performed with a single dose of MTX (20 mg/kg) to groups 2 and 3. On the sixth day, animals in all groups were sacrificed by decapitation and lung tissue and blood samples were removed for histological examination and also measurement the levels of interleukin-1-beta (IL-1β), malondialdehyde (MDA), glutathione (GSH), tumour necrosis factor-alpha (TNF-α), myeloperoxidase (MPO), and sodium potassium-adenosine triphosphatase (Na+/K+ATPase).

RESULTS

In MTX group tissue GSH, Na+/K+ATPase activities were lower, tissue MDA, MPO and plasma IL-1?, TNF-? were significantly higher than the other groups. Histopathological examination showed that lung injury was less severe in group 2 according to group 3.

CONCLUSIONS

Oxidative damage of MTX in rat lung is partially reduced when combined with ALA.

CMX-2043 Efficacy in a Rat Model of Cardiac Ischemia–Reperfusion Injury

α-Lipoic acid (LA) has been shown to offer protection against ischemia–reperfusion injury (IRI) in multiple organ systems. N-[(R)-1,2-dithiolane-3-pentanoyl]-L-glutamyl-L-alanine (CMX-2043), a novel analogue of LA, was studied as part of a preclinical development program intended to identify safe and efficacious drug candidates for prevention or reduction in myocardial IRI. This study was designed to evaluate the efficacy of CMX-2043 in an animal model of myocardial IRI and to establish effective dosing conditions. CMX-2043 or placebo was administered at different doses, routes, and times in male Sprague-Dawley rats subjected to 30-minute left coronary artery ligation. Fluorescent microsphere injection defined the area at risk (AR). Animals were euthanized 24 hours after reperfusion, and the hearts were excised, sectioned, and stained with triphenyltetrazolium. Cytoprotective effectiveness was determined by comparing the unstained myocardial infarction zone (MI) to the ischemic AR. The reduction in the MI–AR ratio was used as the primary measure of drug efficacy relative to placebo injections. Treatment with CMX-2043 reduced myocardial IRI as measured by the MI–AR ratio and the incidence of arrhythmia. The compound was effective when administered by injection, both before and during the ischemic injury and at reperfusion. The most efficacious dose was that administered 15 minutes prior to the ischemic event and resulted in a 36% ( P < .001) reduction in MI–AR ratio compared to vehicle control.

Does the intrathecal propofol have a neuroprotective effect on spinal cord ischemia?

The neuroprotective effects of propofol have been confirmed. However, it remains unclear whether intrathecal administration of propofol exhibits neuroprotective effects on spinal cord ischemia. At 1 hour prior to spinal cord ischemia, propofol (100 and 300 µg) was intrathecally administered in rats with spinal cord ischemia. Propofol pre-treatment greatly improved rat pathological changes and neurological function deficits at 24 hours after spinal cord ischemia. These results suggest that intrathecal administration of propofol exhibits neuroprotective effects on spinal cord structural and functional damage caused by ischemia.

Benefits of the antioxidant and anti-inflammatory activity of etoricoxib in the prevention of ovarian ischemia/reperfusion injury induced experimentally in rats

AIM

This study is a biochemical investigation of the effect of etoricoxib, a selective cyclooxygenase (COX)-2 inhibitor, on ischemia/reperfusion (I/R) injury experimentally induced in rat ovaries.

METHODS

Experimental animals were divided into four groups: (i) ovarian ischemia/reperfusion (IRG); (ii) 30 mg/kg etoricoxib + ovarian ischemia/reperfusion (EIRG-30); (iii) 60 mg/kg etoricoxib + ovarian ischemia/reperfusion (EIRG-60); and (iv) a sham operation (SG) control group.

RESULTS

The results showed levels of malondialdehyde in the IRG, EIRG-30, EIRG-60 and SG group ovarian tissue of 20.2 ± 3.4, 11.2 ± 3.2, 5.5 ± 1.9 and 3.8 ± 1.5 μmol/g protein, respectively. Myeloperoxidase activity for these groups was 24.2 ± 6.7, 13 ± 2.4, 4 ± 1.8 and 3.5 ± 1.9 U/g protein, and total glutathione levels were 1.6 ± 0.8, 4.5 ± 1.9, 6.5 ± 1.9 and 7.5 ± 2.4 nmol/g protein, respectively. COX-1 activity in IRG, EIRG-30, EIRG-60 and SG group rat ovarian tissue was 5.0 ± 2.8, 12.2 ± 2.4, 16.7 ± 2.8 and 17.5 ± 4.7 U/mg protein, and COX-2 activity was 18.3 ± 2.7, 3.5 ± 1, 1.8 ± 0.7 and 0.7 ± 0.3 U/mg protein, respectively.

CONCLUSION

Etoricoxib prevented oxidative damage induced with I/R in rat ovarian tissue. This property of etoricoxib suggests that it can be clinically beneficial in the prevention of damage that may arise with reperfusion by detorsion for the protection of the ovaries against torsion.

Protective Effect of Alpha Lipoic Acid on Rat Sciatic Nerve Ischemia Reperfusion Damage

BACKGROUND

Alpha lipoic acid is a potent antioxidant that plays numerous roles in human health. This study examined the effect of ALA on rat sciatic nerve ischemia reperfusion damage.

AIMS

Protective effect of alpha lipoic acid (ALA) on sciatic nerve following ischemia-reperfusion in rats was investigated by using light microscopy and biochemical methods. Provided that the protective effect of ALA on sciatic nerve is proven, we think the damage to the sciatic nerve that has already occurred or might occur in patients for various reasons maybe prevented or stopped by giving ALA in convenient doses.

STUDY DESIGN

Animal experiment.

METHODS

Forty-two adult male Sprague-Dawley rats (250-300 grams) were used in this study. Rats were randomly divided into six groups including one control (Group 1), one sham (Group 2), two ischemia-reperfusion (Groups 3 and 4) and two treatment groups (Groups5 and 6). Doses of 60 and 100 mg/kg ALA were given (Group 5 and 6) intra peritoneally twice, 1 and 24 hours before the ischemia to each treatment group. Ischemia was carried out the abdominal aorta starting from the distal part of the renal vein for two hours followed by reperfusion for three hours. In immunohistochemical methods, fibronectin immunoreactivity was analyzed. For biochemical analyses, the tissues were taken in eppendorf microtubes and superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) enzyme activities as well as malondialdehyde (MDA) and nitricoxide (NO) levels were measured.

RESULTS

Fibronectin was observed to have increased significantly in the ischemia group; on the other hand, it was observed to have decreased in parallel to the doses in the ALA groups. Biochemical studies showed that SOD and GSHPx declined with ischemia-reperfusion, but the activities of these enzymes were increased in the treatment groups in parallel with the dose. It was found that increased MDA levels with ischemia-reperfusion were decreased in parallel with ALA dose. There were no statistically significant changes in NO.

CONCLUSION

Increased fibronectin observed after ischemia/reperfusion of rat sciatic nerve is reduced after the administration of ALA. This indicates that the function of fibronectin, to reconnect cut nerve segments and regenerate nerves, is more prominent than its function in tissue healing after ischemia. ALA administered before ischemia decreases MDA and increases SOD and GSHPx. We think that ALA may protect against the pathological changes in ischemic nerve and may be used to devise more efficient treatments.

Green tea polyphenols protect spinal cord neurons against hydrogen peroxide-induced oxidative stress

Green tea polyphenols are strong antioxidants and can reduce free radical damage. To investigate their neuroprotective potential, we induced oxidative damage in spinal cord neurons using hydrogen peroxide, and applied different concentrations (50–200 μg/mL) of green tea polyphenol to the cell medium for 24 hours. Measurements of superoxide dismutase activity, malondialdehyde content, and expression of apoptosis-related genes and proteins revealed that green tea polyphenol effectively alleviated oxidative stress. Our results indicate that green tea polyphenols play a protective role in spinal cord neurons under oxidative stress.

Neuroprotective effect of alpha-lipoic acid and methylprednisolone on the spinal cord ischemia/reperfusion injury in rabbits

OBJECTIVE

The aim of this study is to investigate the putative neuroprotective effect of alpha-lipoic acid (LA) on spinal ischemia/reperfusion (I/R) injury in rabbits.

METHODS

Thirty-five adult female New Zeland rabbits, weighing 2,000-3,500 g (mean: 2,800), were divided randomly into five groups of seven rabbits each (n: 7) as Group 1: sham, only laparotomy; Group 2 (İ/R): I/R; Group 3 (LA): I/R and 100 mg/kg of LA; Group 4 (MP): I/R and 30 mg/kg of methylprednisolone (MP); and Group 5 (LA + MP): I/R and 100 mg/kg of LA plus 30 mg/kg of MP.

RESULTS

A statically significant effect of LA, MP, and LA plus MP on lowering malondialdehyde levels both in the blood and in the cerebrospinal fluid (CSF) has been observed. Nitric oxide is significantly decreased in the blood and spinal cord tissues, and also in the CSF but it is not significant. Superoxide dismutase, catalase, and glutathione levels were increased by LA administration.

CONCLUSION

LA exhibits antioxidant efficacy in spinal cord I/R injury, but it cannot decrease the oxidative stress. The histopathological result of the present study also demonstrated that LA has neuroprotective effect in spinal cord injury.

α-Lipoic acid reduces infarct size and preserves cardiac function in rat myocardial ischemia/reperfusion injury through activation of PI3K/Akt/Nrf2 pathway

Background

The present study investigates the effects and mechanisms of α-Lipoic acid (LA) on myocardial infarct size, cardiac function and cardiomyocyte apoptosis in rat hearts subjected to in vivo myocardial ischemia/reperfusion (MI/R) injury.

Methodology/Principal Findings

Male adult rats underwent 30 minutes of ischemia followed by 3, 24, or 72 h of reperfusion. Animals were pretreated with LA or vehicle before coronary artery ligation. The level of MI/R- induced LDH and CK release, infarct size, cardiomyocyte apoptosis and cardiac functional impairment were examined and compared. Western blot analysis was performed to elucidate the mechanism of LA pretreatment. The level of inflammatory cytokine TNF-α released to serum and accumulated in injured myocardium as well as neutrophil accumulation in injured myocardium were also examined after MI/R injury. Our results reveal that LA administration significantly reduced LDH and CK release, attenuated myocardial infarct size, decreased cardiomyocytes apoptosis, and partially preserved heart function. Western blot analysis showed that LA pretreatment up-regulated Akt phosphorylation and Nrf2 nuclear translocation while producing no impact on p38MAPK activation or nitric oxide (NO) production. LA pretreatment also increased expression of HO-1, a major target of Nrf2. LA treatment inhibited neutrophil accumulation and release of TNF-α. Moreover, PI3K inhibition abolished the beneficial effects of LA.

Conclusions/Significance

This study indicates that LA attenuates cardiac dysfunction by reducing cardiomyoctyes necrosis, apoptosis and inflammation after MI/R. LA exerts its action by activating the PI3K/Akt pathway as well as subsequent Nrf2 nuclear translocation and induction of cytoprotective genes such as HO-1.

Nutraceutical strategies for ameliorating the toxic effects of alcohol

Rodent studies reveal that oxidative stress, much of it generated via induction/activation of NADPH oxidase, is a key mediator of a number of the pathogenic effects of chronic ethanol overconsumption. The highly reactive ethanol metabolite acetaldehyde is a key driver of this oxidative stress, and doubtless works in other ways to promote alcohol-induced pathology. Effective antioxidant measure may therefore be useful for mitigating the adverse health consequences of alcohol consumption; spirulina may have particular utility in this regard, as its chief phycochemical phycocyanobilin has recently been shown to function as an inhibitor of certain NADPH oxidase complexes, mimicking the physiological role of its chemical relatives biliverdin/bilirubin in this respect. Moreover, certain nutraceuticals, including taurine, pantethine, and lipoic acid, may have the potential to boost the activity of the mitochondrial isoform of aldehyde dehydrogenase, ALDH-2, accelerating conversion of acetaldehyde to acetate (which arguably has protective health effects). Little noticed clinical studies conducted nearly three decades ago reported that pre-ingestion of either taurine or pantethine could blunt the rise in blood acetaldehyde following ethanol consumption. Other evidence suggests that lipoic acid may function within mitochondria to maintain aldehyde dehydrogenase in a reduced active conformation; the impact of this agent on ethanol metabolism has however received little or no study. Studies evaluating the impact of nutracetical strategies on prevention of hangovers - which likely are mediated by acetaldehyde - may represent a quick, low-cost way to identify nutraceutical regimens that merit further attention for their potential impact on alcohol-induced pathology. Measures which boost or preserve ALDH-2 activity may also have important antioxidant potential, as this enzyme functions physiologically to protect cells from toxic aldehydes generated by oxidant stress.

The effects of α-lipoic acid against testicular ischemia-reperfusion injury in Rats

Testicular torsion is one of the urologic emergencies occurring frequently in neonatal and adolescent period. Testis is sensitive to ischemia-reperfusion injury, and, therefore, ischemia and consecutive reperfusion cause an enhanced formation of reactive oxygen species that result in testicular cell damage and apoptosis. α-lipoic acid is a free radical scavenger and a biological antioxidant. It is widely used in the prevention of oxidative stress and cellular damage. We aimed to investigate the protective effect of α-lipoic acid on testicular damage in rats subjected to testicular ischemia-reperfusion injury. 35 rats were randomly divided into 5 groups: control, sham operated, ischemia, ischemia-reperfusion, and ischemia-reperfusion +lipoic acid groups, 2 h torsion and 2 h detorsion of the testis were performed. Testicular cell damage was examined by H-E staining. TUNEL and active caspase-3 immunostaining were used to detect germ cell apoptosis. GPx , SOD activity, and MDA levels were evaluated. Histological evaluation showed that α-lipoic acid pretreatment reduced testicular cell damage and decreased TUNEL and caspase-3-positive cells. Additionally, α-lipoic acid administration decreased the GPx and SOD activity and increased the MDA levels. The present results suggest that LA is a potentially beneficial agent in protecting testicular I/R in rats.

Melatonin treatment protects against spinal cord injury induced functional and biochemical changes in rat urinary bladder

Oxidative stress induced by spinal cord injury (SCI) has deleterious effects on the function of several organ systems including the urinary bladder. In this study, we investigated the possible protective actions of melatonin on SCI-induced oxidative damage and urinary bladder dysfunction. Wistar albino rats (n = 24) were divided randomly as control, vehicle- or melatonin (10 mg/kg, ip)-treated SCI groups. To induce SCI, a standard weight-drop method that induced a moderately severe injury at T10 was used. Injured animals were given either vehicle or melatonin 15 min postinjury. One week postinjury, each rat was neurologically examined and then decapitated; blood samples were taken to evaluate neuron-specific enolase (NSE) and soluble protein 100β (S-100β). Spinal cord (SC) and urinary bladder samples were taken for functional studies and histological examination or stored for the measurement of malondialdehyde (MDA), glutathione (GSH) and nerve growth factor (NGF) levels and caspase-3 activity. Isometric contractions in bladder strips were induced by carbachol. In the SCI rats, decreased contractile responses of the bladder strips were found to be restored by melatonin treatment. Serum S-100β levels and NSE activities and tissue MDA levels and caspase-3 activities, all of which were elevated in the vehicle-treated SCI animals as compared to the control values, were reversed by melatonin treatment. On the other hand, reduced GSH and NGF levels due to SCI were restored by melatonin treatment. Furthermore, melatonin treatment improved histological findings. These findings suggest that melatonin reduces SCI-induced tissue injury and improves bladder functions through its effects on oxidative stress and NGF.

Neuroprotective effects of PEP-1-Cu,Zn-SOD against ischemic neuronal damage in the rabbit spinal cord

A rabbit model of spinal cord ischemia has been introduced as a good model to investigate the pathophysiology of ischemia-reperfusion (I-R)-induced paraplegia. In the present study, we observed the effects of Cu,Zn-superoxide dismutase (SOD1) against ischemic damage in the ventral horn of L(5-6) levels in the rabbit spinal cord. For this study, the expression vector PEP-1 was constructed, and this vector was fused with SOD1 to create a PEP-1-SOD1 fusion protein that easily penetrated the blood-brain barrier. Spinal cord ischemia was induced by transient occlusion of the abdominal aorta for 15 min. PEP-1-SOD1 (0.5 mg/kg) was intraperitoneally administered to rabbits 30 min before ischemic surgery. The administration of PEP-1-SOD1 significantly improved neurological scores compared to those in the PEP-1 (vehicle)-treated ischemia group. Also, in this group, the number of cresyl violet-positive cells at 72 h after I-R was much higher than that in the vehicle-treated ischemia group. Malondialdehyde levels were significantly decreased in the ischemic spinal cord of the PEP-1-SOD1-treated ischemia group compared to those in the vehicle-treated ischemia group. In contrast, the administration of PEP-1-SOD1 significantly ameliorated the ischemia-induced reduction of SOD and catalase levels in the ischemic spinal cord. These results suggest that PEP-1-SOD1 protects neurons from spinal ischemic damage by decreasing lipid peroxidation and maintaining SOD and catalase levels in the ischemic rabbit spinal cord.