Myocardial ischemia/reperfusion (MI/R) leads to oxidative stress, which may in turn lead to myocardial injury. In the present study, we investigated the effects of exenatide, a glucagon-like peptide-1 (GLP-1) analogue, on oxidative stress-induced injury in vitro and in vivo. In in vitro experiments, H9c2 cells were incubated with exenatide to determine the direct cytoprotective effects of exenatide following exposure to hydrogen peroxide (H2O2). Pre-treatment with exenatide (1 nM), prior to H2O2 exposure, increased cell viability and inhibited H2O2-induced reactive oxygen species (ROS) production. Exenatide also decreased the levels of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) in the cultured supernatants, as well as those of malondialdehyde (MDA) in the H9c2 cells and increased the total superoxide dismutase (T-<em>SOD</em>) levels in the H9c2 cells. In in vivo experiments, an animal model of MI/R was induced by coronary occlusion. Pre-treatment with exenatide (10 µg/kg/day) protected the rat hearts from MI/R-induced injury by decreasing the levels of LDH and CK-MB in plasma, increasing the levels of catalase, T-<em>SOD</em> and glutathione peroxidase (GSH-Px) in the heart and decreasing the MDA levels in the rats with MI/R-induced injury. Exenatide also reduced the infarct size and enhanced cardiac function in the rats with MI/R-induced injury. Moreover, pre-treatment with exenatide inhibited cardiomyocyte apoptosis, increased Aktserine47<em>3</em> and Badserine1<em>3</em>6 phosphorylation and decreased cleaved caspase-<em>3</em> expression in vitro and in vivo; however, these effects were attenuated by the phosphoinositide <em>3</em>-kinase (PI<em>3</em>K) inhibitor, LY294002. Our results suggest that exenatide exerts significant cardioprotective effects against oxidative stress-induced injury in vitro and in vivo. The mechanisms involved may be attributed to the scavenging of oxidative stress products, such as ROS, the increase in the concentrations of antioxidant defense enzymes and the inhibition of cardiomyocyte apoptosis. The anti-apoptotic effects of exenatide were, at least in part, associated with the activation of the PI<em>3</em>K/Akt signaling pathway.

The present investigation reports the effect of rosmarinic acid (RA), an antioxidant on gentamicin sulphate (GS)-induced renal oxidative damage in rats. Rosmarinic acid (RA) has been demonstrated to have antioxidant, free radical scavenger and anti-inflammatory effects. Twenty-eight Sprague-Dawley rats were divided in to four equal groups as follows: group 1 (control), group 2 (GS 100 mg/kg/d ip), group <em>3</em> (GS 100 mg/kg/d ip+RA 50 mg/kg/d) and group 4 (GS 100 mg/kg/d ip+RA 100 mg/kg/d). Treatments were administrated once daily for 12 days. After 12 days 24h urine was collected, blood was sampled and kidneys were removed. Serum and kidney tissue MDA assessed by thiobarbituric acid. Kidney paraffin sections (5 μm thickness) from the left kidney stained with periodic acid Schiff. Tubular necrosis was studied semiquantitatively and glomerular volume and volume density of proximal convoluted tubule (PCT) estimated stereologically. Kidney homogenize were prepared from right kidney. Serum creatinine, urea and kidney antioxidant enzymes activity were assessed by special kits. Data were compared by SPSS 1<em>3</em> software and Mann-Whitney test at p < 0.05. Co treatment of GS and RA (High dose) significantly decreased serum creatinine, MDA, urea, tubular necrosis (p < 0.05) and increase renal GSH, GPX, CAT, <em>SOD</em>, volume density of PCT and creatinine clearance significantly in comparison with GS group (p < 0.05). Treatment with RA (high dose) maintained serum creatinine, volume density of PCT, renal GSH, GPX, <em>SOD</em> and MDA as the same level as control group significantly (p < 0.05). In conclusion, RA alleviates GS nephrotoxicity via antioxidant activity, increase of renal GSH content and increase of renal antioxidant enzymes activity.

OBJECTIVE

Neonates that survive very preterm birth have a high prevalence of cognitive impairment in later life. A common factor detected in premature infants is their postnatal exposure to high oxygen tension relative to that in utero. Hyperoxia is known to elicit injury to premature lung and retina. Because data on the exposure of the brain to hyperoxia are limited, we studied the effects of high oxygen on this tissue.

METHODS

Rat pups were exposed from birth until day 6 to 21% or 80% O(2). Cerebral vascular density was quantified by lectin immunohistochemistry. Immunoblots for several proteins were performed on brain extracts. We assessed cerebral functional deficits by visual evoked potentials.

RESULTS

Exposure of pups to hyperoxia leads to cerebral microvascular degeneration, diminished brain mass, and cerebral functional deficits. These effects are preceded by an upregulation of endothelial nitric oxide synthase (eNOS) in cerebral capillaries and a downregulation of Cu/Zn superoxide dismutase (<em>SOD</em>). The imbalance in nitric oxide (NO) production and antioxidant defenses favors the formation of nitrating agents in the microvessels revealed by increased nitrotyrosine (<em>3</em>-nt) immunoreactivity and decreased expression of NF-kappaB and the dependent vascular endothelial growth factor receptor 2. NOS inhibitors and eNOS deletion as well as an <em>SOD</em> mimetic (CuDIPS) restore vascular endothelial growth factor receptor-2 levels and nearly abolish the vasoobliteration. NOS inhibitors and <em>SOD</em> mimetic also prevent O(2)-induced diminished brain mass and functional deficit.

CONCLUSIONS

Data identify NO and nitrating agents as major mediators of cerebral microvascular damage, ensuing impaired brain development and function in immature subjects exposed to hyperoxia.

To investigate the antioxidant defense system, chilling stress-induced changes of antioxidant enzymes were examined in the leaves of cucumber (Cucumis sativus L.). Chilling stress preferentially enhanced the activities of the superoxide dismutase (<em>SOD</em>), ascorbate peroxidase (APX), glutathione reductase (GR) and peroxidase specific to guaiacol, whereas it induced the decrease of catalase activity. In order to analyze the changes of antioxidant enzyme isoforms against chilling stress, foliar extracts were subjected to native PAGE. Leaves of cucumber had four isoforms of Mn-<em>SOD</em> and two isoforms of Cu/Zn-<em>SOD</em>. Fe-<em>SOD</em> isoform was not observed in this plant. Expression of Cu/Zn-<em>SOD</em> and Mn-<em>SOD</em> was preferentially enhanced by chilling stress. Expression of Mn-<em>SOD</em>-2 and -4 was enhanced after 48 h of the poststress period. Five APX isoforms were presented in the leaves of cucumber. The intensities of APX-4 and -5 were enhanced by chilling stress, whereas that of APX-<em>3</em> was significantly increased in the poststress periods after chilling stress. Gel stained for GR activity revealed six isoforms in the plant. Activation levels for most of GR isoforms were higher in the stressed-plants than the control and poststressed-plants, but that of GR-1 isoform was significantly higher in the poststressed-plants than chilling stressed-plants. These results collectively suggest that chilling stress activates the enzymes of an <em>SOD</em>/ascorbate-glutathione cycle under catalase deactivation in the leaves of cucumber, but the response timing of enzyme isoforms against various environmental stresses is not the same for all isoforms of antioxidant enzymes.

Skin fibrosis is characterized by the proliferation and accumulation of activated fibroblasts called myofibroblasts. They exhibit specific cytoskeletal differentiation, overexpress the fibrogenic cytokine TGF-beta1, synthesize excess extracellular matrix compounds and exhibit a depleted antioxidant metabolism. Recently, <em>SOD</em> was successfully used as an antifibrotic agent in vivo, thus challenging the postulate of established fibrosis irreversibility. We postulated that myofibroblasts could be a direct target for this therapeutic effect. To test this hypothesis, we used three-dimensional co-culture models of skin, in which specific phenotypes of normal fibroblasts versus myofibroblasts are retained. These <em>3</em>-D models were treated with liposomal and carrier-free Cu/Zn <em>SOD</em>, and examined for their effects on cell number, cell death, and phenotypic differentiation. The results show that <em>SOD</em> did not induce myofibroblast cell death, whereas it significantly reduced TGF-beta1 expression, thus demonstrating that <em>SOD</em> might be proposed as a potent antagonist of this major fibrogenic growth factor. We also found that <em>SOD</em> significantly lowered the levels of the myofibroblast marker alpha-sm actin, of beta-actin, and of the extracellular matrix components alpha1(I) collagen and tenascin-C. In conclusion, our results suggest that <em>SOD</em> antifibrotic action occurred in vitro through the reversion of myofibroblasts into normal fibroblasts.

Metallothioneins (MTs) are major zinc binding proteins in the CNS that could be involved in the control of zinc metabolism as well as in protection against oxidative stress. Mice lacking MT-I and MT-II (MT-I + II deficient) because of targeted gene inactivation were injected with kainic acid (KA), a potent convulsive agent, to examine the neurobiological importance of these MT isoforms. At <em>3</em>5 mg/kg KA, MT-I + II deficient male mice showed a higher number of convulsions and a longer convulsion time than control mice. Three days later, KA-injected mice showed gliosis and neuronal injury in the hippocampus. MT-I + II deficiency decreased both astrogliosis and microgliosis and potentiated neuronal injury and apoptosis as shown by terminal deoxynucleotidyl transferase-mediated in situ end labelling (TUNEL), detection of single stranded DNA (ssDNA) and by increased interleukin-1beta-converting enzyme (ICE) and caspase-<em>3</em> levels. Histochemically reactive zinc in the hippocampus was increased by KA to a greater extent in MT-I + II-deficient compared with control mice. KA-induced seizures also caused increased oxidative stress, as suggested by the malondialdehyde (MDA) and protein tyrosine nitration (NITT) levels and by the expression of MT-I + II, nuclear factor-kappaB (NF-kappaB), and Cu/Zn-superoxide dismutase (Cu/Zn-<em>SOD</em>). MT-I + II deficiency potentiated the oxidative stress caused by KA. Both KA and MT-I + II deficiency significantly affected the expression of MT-III, granulocyte-macrophage colony stimulating factor (GM-CSF) and its receptor (GM-CSFr). The present results indicate MT-I + II as important for neuron survival during KA-induced seizures, and suggest that both impaired zinc regulation and compromised antioxidant activity contribute to the observed neuropathology of the MT-I + II-deficient mice.

Oxidative stress is caused by an imbalance between the antioxidant and the reactive oxygen species, which results in damage to cells or tissues. Recent studies have reported that oxidative stress is involved in obesity, in addition to many other human diseases and aging. A prospective, randomized, double-blind study was performed to investigate the effect of astaxanthin (ASX), which is known to be a potent antioxidant, on oxidative stress in overweight and obese adults in Korea. Twenty-three adults with BMI>> 25.0 kg/m(2) enrolled in this study and were randomly assigned to two dose groups: ASX 5 mg and 20 mg once daily for <em>3</em> weeks. Malondialdehyde (MDA), isoprostane (ISP), superoxide dismutase (<em>SOD</em>) and total antioxidant capacity (TAC), as oxidative stress biomarkers, were measured at baseline and 1, 2 and <em>3</em> weeks after ASX administration. Compared with baseline, the MDA (by <em>3</em>4.6% and <em>3</em>5.2%) and ISP (by 64.9% and 64.7%) levels were significantly lowered, whereas <em>SOD</em> (by 19<em>3</em>% and 194%) and TAC (by 121% and 125%) levels were significantly increased in two dose groups after the <em>3</em> week intervention. This study revealed that supplemental ASX for <em>3</em> weeks improved oxidative stress biomarkers by suppressing lipid peroxidation and stimulating the activity of the antioxidant defense system.

OBJECTIVE

Leukocyte infiltration, up-regulation of proinflammatory cytokines and severe oxidative stress caused by increased amounts of reactive oxygen species are characteristics of inflammatory bowel disease. The catechin (2R,<em>3</em>R)-2-(<em>3</em>,4,5-Trihydroxyphenyl)-<em>3</em>,4-dihydro-1(2H)-benzopyran-<em>3</em>,5,7-triol-<em>3</em>-(<em>3</em>,4,5-trihydroxybenzoate), named epigallocatechin-<em>3</em>-gallate, EGCG, has been demonstrated to exert anti-inflammatory and antioxidative properties, reducing reactive oxygen species in the inflamed tissues. The aim of this study was to evaluate the therapeutic effects of EGCG in a murine model of colitis induced by oral administration of dextran sodium sulfate.

METHODS

Mice received a daily oral administration of 6.9 mg/kg body weight EGCG or Piper nigrum (L.) alkaloid (2E,4E)-5-(1,<em>3</em>-benzodioxol-5-yl)-1-piperidin-1-ylpenta-2,4-dien-1-one, named piperine (2.9 mg/kg body weight) or the combination of the both - piperine was used in this combination to enhance the bioavailability of EGCG.

RESULTS

In vivo data revealed the combination of EGCG and piperine to significantly reduce the loss of body weight, improve the clinical course and increase overall survival in comparison to untreated groups. The attenuated colitis was associated with less histological damages to the colon and reduction of tissue concentrations of malondialdehyde, the final product of lipid peroxidation. Neutrophils accumulation indicator myeloperoxidase was found to be reduced in colon tissue, while antioxidant enzymes like superoxide dismutase and glutathione peroxidase showed an increased activity. In vitro, the treatment with EGCG plus piperine enhanced the expression of SOD as well as GPO and also reduced the production of proinflammatory cytokines.

CONCLUSIONS

These data support the concept of anti-inflammatory properties of EGCG being generally beneficial in the DSS-model of colitis, an effect that may be mediated by its strong antioxidative potential.

Multiple myeloma (MM), neoplastic disorder, is a B-cell malignancy characterised by the accumulation of clonal population of plasma cells. Reactive oxygen species and other free radicals mediate phenotypic and genotypic changes leading from mutation to neoplasia in all cancers including MM. In the present study, 50 clinically diagnosed patients with MM at stage II of international staging system and 50 healthy controls were included. beta(2) microglobulin levels were estimated by ELISA. The circulating levels of enzymatic antioxidants; superoxide dismutase (<em>SOD</em>), glutathione peroxidase (GPX) were spectrophotometrically estimated using RANDOX kits whereas catalase, malondialdehyde (MDA), vitamin C and E were estimated by standardised protocols using spectrophotometer/fluorometer. The serum beta(2) microglobulin levels were significantly higher >><em>3</em> microg/mL) in patients with MM than healthy controls. The estimated levels of <em>SOD</em>, GPX and catalase (enzymatic antioxidants) and vitamin C and E (non-enzymatic antioxidants) were significantly declined in patients whereas MDA levels were elevated as compared with controls. These results suggest that MM is closely associated with oxidative stress and reduced antioxidant capacity and further investigation might provide an insight to understand a putative causal link between oxidative stress and MM disease progression.

Ulcerative colitis is a chronic inflammatory disorder characterized by oxidative stress, leucocyte infiltration and upregulation of pro-inflammatory cytokines. The aim of the present study was to examine the effect of amentoflavone on a murine model of ulcerative colitis (UC). UC was induced by intracolonic injection of <em>3</em>% acetic acid in male Wistar rats. amentoflavone (10 mg/kg·b.wt) or reference drug sulfasalazine (100 mg/kg·b.wt) was administrated intra-peritoneally for 5 consecutive days before induction of colitis with acetic acid. Administration of amentoflavone was found to reduce the extent of inflammatory colonic injury. This was manifested by a decrease in the score of mucosal injury, by lowered colonic wet weight as well as vascular permeability and diminished lactate dehydrogenase (LDH) and myeloperoxidase (MPO) activity reflecting reduced leukocyte infiltration. Furthermore, the mucosal content of lipid peroxidation (LPO), glutathione (GSH), superoxide dismutase (<em>SOD</em>), nitric oxide (NO) activity confirms that amentoflavone could significantly inhibit colitis. The treatment also reduced significantly the colonic tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and IL-6 levels as well as the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) compared to colitis control group. The histopathological studies also confirm the foregoing findings. amentoflavone was also able to inhibit the activation and translocation of transcription factors, nuclear factor (NF)-κB subunits (p65/p50). These results suggest that amentoflavone exhibits protective effect in acetic acid-induced ulcerative colitis which might be due to its modulation of oxidant/anti-oxidant balance, down-regulation of productions and expressions of pro-inflammatory cytokines, inflammatory mediators and inhibition of NF-κB signal transduction pathways.

Probiotics participate actively in the neuropsychiatric disorders. However, their roles on ischemic stroke remain unclear. This study aims to determine whether Clostridium butyricum (C. butyricum) could attenuate cerebral ischemia/reperfusion (I/R) injury and its possible mechanisms. Male ICR mice were intragastrically pretreated with C. butyricum for 2 successive weeks, and then subjected to cerebral I/R injury induced by the bilateral common carotid artery occlusion (BCCAO) for 20min. After 24h of the reperfusion, neurological deficit scores were evaluated. Histopathological changes of the hippocampus neurons were observed using Hematoxylin and eosin (H&E) and TUNEL staining. Malondialdehyde (MDA) contents and superoxide dismutase (<em>SOD</em>) activities in the brain were detected. The expression of Caspase-<em>3</em>, Bax and Bcl-2 were investigated by Western blot and immunohistochemistry analysis. The butyrate contents in the brain were determined. Our results showed that cerebral I/R injury led to neurological deficit, increased levels of Caspase-<em>3</em> and Bax and decreased Bcl-2/Bax ratio. C. butyricum significantly improved neurological deficit, relieved histopathologic change, decreased MDA contents and increased <em>SOD</em> activities in the I/R injury mice. After C. butyricum pretreatment, the expression of Caspase-<em>3</em> and Bax were significantly decreased, the Bcl-2/Bax ratio was significantly increased, and butyrate contents in the brain were significantly increased. These findings suggested that C. butyricum is able to exert neuroprotective effects against I/R injury mice through anti-oxidant and anti-apoptotic mechanisms, and reversing decrease of butyrate contents in the brain might be involved in its neuroprotection.

Previous studies have shown that nitric oxide (NO) inhibits carotid body sensory activity. To begin to understand the cellular mechanisms associated with the actions of NO in the carotid body, we monitored the effects of NO donors on the macroscopic Ca2+ current in glomus cells isolated from rabbit carotid bodies. Experiments were performed on freshly dissociated glomus cells from adult rabbit carotid bodies using the whole cell configuration of the patch-clamp technique. The NO donors sodium nitroprusside (SNP; 600 microM, n = 7) and spermine nitric oxide (SNO; 100 microM, n = 7) inhibited the Ca2+ current in glomus cells in a voltage-independent manner. These effects of NO donors were rapid in onset and peaked within 1 or 2 min. In contrast, the outward K+ current was unaffected by SNP (600 microM, n = 6), indicating that the inhibition by SNP was not a nonspecific membrane effect. 2-(4-carboxyphenyl)-4,4,5, 5-tetramethyl-imidazoline-1-oxyl-<em>3</em>-oxide (carboxy-PTIO; 500 microM), an NO scavenger, prevented inhibition of the Ca2+ current by SNP (n = 7), whereas neither superoxide dismutase (<em>SOD</em>; 2,000 U/ml, n = 4), a superoxide scavenger, nor sodium hydrosulfite (SHS; 1 mM, n = 7), a reducing agent, prevented inhibition of the Ca2+ current by SNP. However, SNP inhibition of the Ca2+ current was reversible in the presence of either <em>SOD</em> or SHS. These results suggest that NO itself inhibits Ca2+ current in a reversible manner and that subsequent formation of peroxynitrites results in irreversible inhibition. SNP inhibition of the Ca2+ current was not affected by <em>3</em>0 microM LY 8<em>3</em>, 58<em>3</em> (n = 7) nor was it mimicked by 600 microM 8-bromoguanosine <em>3</em>':5'-cyclic monophosphate (8-Br-cGMP; n = 6), suggesting that the effects of NO on the Ca2+ current are mediated, in part, via a cGMP-independent mechanism. N-ethylmaleimide (NEM; 2.5 mM, n = 6) prevented the inhibition of the Ca2+ current by SNP, indicating that SNP is acting via a modification of sulfhydryl groups on Ca2+ channel proteins. Norepinephrine (NE; 10 microM) further inhibited the Ca2+ current in the presence of NEM (n = 7), implying that NEM did not nonspecifically eliminate Ca2+ current modulation. Nisoldipine, an L-type Ca2+ channel blocker (2 microM, n = 6), prevented the inhibition of Ca2+ current by SNP, whereas omega-conotoxin GVIA, an N-type Ca2+ channel blocker (1 microM, n = 9), did not prevent the inhibition of Ca2+ current by SNP. These results demonstrate that NO inhibits L-type Ca2+ channels in adult rabbit glomus cells, in part, due to a modification of calcium channel proteins. The inhibition might provide one plausible mechanism for efferent inhibition of carotid body activity by NO.

It has been shown that reactive oxygen species (ROS) are involved in the intracellular signaling response to G-protein coupled receptor stimuli in vascular smooth muscle cells and in neurons. In the present study, we tested the hypothesis that NAD(P)H oxidase-derived ROS are involved endothelin-1 (ET-1)-induced L-type calcium channel activation in isolated cardiac myocytes. ET-1 (10 nM) induced a 2-fold increase in L-type calcium channel open-state probability (NPo). This effect of ET-1 was abolished by the ET(A) receptor antagonist cyclo(D-Trp-D-Asp-Pro-D-Val-Leu) [BQ-12<em>3</em> (1 microM)] but was not altered in the presence of an ET(B) receptor antagonist N-cis-2,6-dimethylpiperidinocarbonyl-b-tBu-Ala-D-Trp(1-methoxycarbonyl)-D-Nle-OH [BQ-788 (1 microM)]. Pretreatment of cells with the ROS scavenger tempol (100 microM), polyethylene glycol-superoxide dismutase (<em>SOD</em>, 25 U/ml), or the NAD(P)H-oxidase inhibitor gp91ds-tat ([H]RKKRRQRRR-CSTRIRRQL[NH(<em>3</em>)]) (5 microM) significantly attenuated ET-1-induced increases in calcium channel NPo. Tempol, <em>SOD</em>, and gp91ds-tat alone had no effect on basal calcium channel activity. In addition, ET-1 significantly increased NAD(P)H oxidase activity and elevated intracellular superoxide levels in cultured cardiac myocytes. The superoxide generator, xanthine-xanthine oxidase (10 mM, 20 mU/ml), also increased calcium channel NPo in cardiac myocytes, mimicking the effect of ET-1. These observations provide the first evidence that ET-1 induces the activation of L-type Ca(2+) channels via stimulation of NAD(P)H-derived superoxide production in cardiac myocytes.

Increased oxidative stress and impaired anti-oxidant defense have been suggested as contributory factors for initiation and progression of complications in diabetes mellitus. Aging itself has been shown to be along with increased oxidative stress and lower anti-oxidant defense. We aimed at investigating oxidative stress and anti-oxidant enzymes in 61 elderly subjects. Fifteen healthy individuals (group 1, mean age 72.2 +/- 5.1<em>3</em>), 1<em>3</em> glucose intolerant patients (group 2, mean age 71.7 +/- 4.9), 19 patients with type 2 diabetes mellitus (T2DM) without any complication (group <em>3</em>, mean age 70.0 +/- 6.0), and 14 patients with T2DM with at least one complication (group 4, mean age 69.8 +/- 4.7) were included in the study. Whilst plasma levels for malondialdehyde (MDAP) and erythrocyte malondialdehyde (MDAE) were measured as markers of oxidative stress, activity of erythrocyte superoxide dismutase (<em>SOD</em>), glutathion peroxidase (GSH-Px), and catalase (CAT) were taken as markers of oxidative defense system. MDAP level was significantly elevated in group 4 (P = 0.001). MDAE was elevated in patients with T2DM, particularly in group 4, however, the difference between the groups was of borderline significance (P = 0.07). Whilst CAT was elevated in groups <em>3</em> and 4 compared to control subjects (P = 0.025 and 0.002, respectively), no difference was found for <em>SOD</em> between the groups. GSH-Px activity was found to be increased in groups 2, <em>3</em> and 4, it did not reach statistical significance (P = 0.106). There were significant correlations between CAT and MDAE (P < 0.0001, r = 0.056) and MDAP (P = 0.016, r = 0.<em>3</em>06). These results suggest that there was an increased oxidative stress in elderly diabetics, however, this is not due to reduced erythrocyte antioxidant defense potential but, rather, increased free radical production possibly due to hyperglycemia.

Free radical-induced oxidative damage is considered to be the most important consequence of the aging process. The activities and capacities of antioxidant systems of cells decline with increased age, leading to the gradual loss of pro-oxidant/antioxidant balance and resulting in increased oxidative stress. Our investigation was focused on the effects of cordycepin (<em>3</em>'-deoxyadenosine) on lipid peroxidation and antioxidation in aged rats. Age-associated decline in the activities of superoxide dismutase (<em>SOD</em>), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), reduced glutathione (GSH), vitamin C and vitamin E, and elevated levels of malondialdehyde (MDA) were observed in the liver, kidneys, heart and lungs of aged rats, when compared to young rats. Furthermore, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, and creatinine were found to be significantly elevated in aged rats compared to young rats. Aged rats receiving cordycepin treatment show increased activity of <em>SOD</em>, CAT, GPx, GR and GST, and elevated levels of GSH, and vitamins C and E such that the values of most of these parameters did not differ significantly from those found in young rats. In addition, the levels of MDA, AST, ALT, urea and creatinine became reduced upon administration of cordycepin to aged rats. These results suggest that cordycepin is effective for restoring antioxidant status and decreasing lipid peroxidation in aged rats.

OBJECTIVE

To evaluate the hematological profile, oxidative stress, and antioxidant parameters in beta-thalassemia/Hb E patients treated with curcuminoids for 12 months.

METHODS

Twenty-one beta-thalassemia/Hb E patients were given 2 capsules of 250 mg each of curcuminoids (a total of 500 mg) daily for 12 months. Blood was collected every 2 months during treatment and <em>3</em> months after withdrawal and was determined for complete blood count, malonyldialdehyde (MDA), superoxide dismutase (<em>SOD</em>), glutathione peroxidase (GSH-Px), reduced glutathione (GSH) in red blood cells (RBC), and non-transferrin bound iron (NTBI) in serum.

RESULTS

The increased oxidative stress in beta-thalassemia/Hb E patients was shown by higher levels of MDA, <em>SOD</em>, GSH-Px in RBC, serum NTBI, and lower level of RBC GSH. Curcuminoids administration resulted in improvement of all the measured parameters as long as they were administered. After <em>3</em> months withdrawal of treatment, all parameters returned close to baseline levels.

CONCLUSIONS

Curcuminoids may be used to ameliorate oxidative damage in patients with beta-thalassemia/Hb E disease.

The aim of the present study was to evaluate the possible protective effects of Nigella sativa L. (NS) against beta-cell damage from streptozotocin (STZ)-induced diabetes in rats. STZ was injected intraperitoneally at a single dose of 50 mg/kg to induce diabetes. NS (0.2 ml/kg/day, i.p.) was injected for <em>3</em> days prior to STZ administration, and these injections were continued throughout the 4-week study. Oxidative stress is believed to play a role in the pathogenesis of diabetes mellitus (DM). To assess changes in the cellular antioxidant defense system, we measured the activities of antioxidant enzymes (such as glutathione peroxidase (GSHPx), superoxide dismutase (<em>SOD</em>), and catalase (CAT)) in pancreatic homogenates. We also measured serum nitric oxide (NO) and erythrocyte and pancreatic tissue malondialdehyde (MDA) levels, a marker of lipid peroxidation, to determine whether there is an imbalance between oxidant and antioxidant status. Pancreatic beta-cells were examined by immunohistochemical methods. STZ induced a significant increase in lipid peroxidation and serum NO concentrations, and decreased antioxidant enzyme activity. NS treatment has been shown to provide a protective effect by decreasing lipid peroxidation and serum NO, and increasing antioxidant enzyme activity. Islet cell degeneration and weak insulin immunohistochemical staining was observed in rats with STZ-induced diabetes. Increased intensity of staining for insulin, and preservation of beta-cell numbers were apparent in the NS-treated diabetic rats. These findings suggest that NS treatment exerts a therapeutic protective effect in diabetes by decreasing oxidative stress and preserving pancreatic beta-cell integrity. Consequently, NS may be clinically useful for protecting beta-cells against oxidative stress.

The biochemical, behavioral and immunohistochemical manifestations were investigated in mice subjected to four experimental schedules with 1-methyl-4-phenyl-1,2,<em>3</em>,6-tetrahydropyridine (MPTP) hydrochloride treatment. The mice were treated intraperitoneally with MPTP (20 mg/kg in saline) four times a day at 2-h intervals showed severe and persistent depletions of dopamine, <em>3</em>,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the striatum and behavioral deficits, as compared with those (1) treated with MPTP (15 mg/kg in saline ip) once a day for 14 consecutive days; (2) MPTP (<em>3</em>0 mg/kg in saline ip) twice a day for five consecutive days; and (<em>3</em>) MPTP (10 mg/kg in saline ip) four times a day at 1-h intervals for two consecutive days. The immunohistochemical study has shown that the acute treatment with MPTP caused severe loss of tyrosine hydroxylase (TH)- and dopamine transporter (DAT)-immunoreactive dopaminergic neurons and marked increase in glial fibrillary acidic protein (GFAP)-immunoreactive astrocytes in the striatum and the substantia nigra. Thus acute treatment of mice with MPTP was accompanied by sustained nigral degeneration and motor abnormalities. Furthermore, our results with Cu/Zn-superoxide dismutase (Cu/Zn-<em>SOD</em>) and manganese superoxide dismutase (Mn-<em>SOD</em>) immunostainings suggest that altered capacity of free radicals quenching may play a key role in the development of the neurons and interneuron damage after MPTP neurotoxicity. Thus, our findings provide valuable information on age-related disease progression and mechanisms of neurodegeneration.

The objective of the present study was to evaluate the efficacy of curcumin, an antioxidant found in turmeric (Curcuma longa) powder (TMP), to ameliorate changes in gene expression in the livers of broiler chicks fed aflatoxin B(1) (AFB(1)). Four pen replicates of 5 chicks each were assigned to each of 4 dietary treatments, which included the following: A) basal diet containing no AFB(1) or TMP (control), B) basal diet supplemented with TMP (0.5%) that supplied 74 mg/kg of curcumin, C) basal diet supplemented with 1.0 mg of AFB(1)/kg of diet, and D) basal diet supplemented with TMP that supplied 74 mg/kg of curcumin and 1.0 mg of AFB(1)/kg of diet. Aflatoxin reduced (P < 0.05) feed intake and BW gain and increased (P < 0.05) relative liver weight. Addition of TMP to the AFB(1) diet ameliorated (P < 0.05) the negative effects of AFB(1) on growth performance and liver weight. At the end of the <em>3</em>-wk treatment period, livers were collected (6 per treatment) to evaluate changes in the expression of genes involved in antioxidant function [catalase (CAT), superoxide dismutase (<em>SOD</em>), glutathione peroxidase (GPx), glutathione S-transferase (GST)], biotransformation [epoxide hydrolase (EH), cytochrome P450 1A1 and 2H1 (CYP1A1 and CYP2H1)], and the immune system [interleukins 6 and 2 (IL-6 and IL-2)]. Changes in gene expression were determined using the quantitative real-time PCR technique. There was no statistical difference in gene expression among the 4 treatment groups for CAT and IL-2 genes. Decreased expression of <em>SOD</em>, GST, and EH genes due to AFB(1) was alleviated by inclusion of TMP in the diet. Increased expression of IL-6, CYP1A1 and CYP2H1 genes due to AFB(1) was also alleviated by TMP. The current study demonstrates partial protective effects of TMP on changes in expression of antioxidant, biotransformation, and immune system genes in livers of chicks fed AFB(1). Practical application of the research is supplementation of TMP in diets to prevent or reduce the effects of aflatoxin in chicks fed aflatoxin-contaminated diets.

BACKGROUND

Because minocycline can cause serious adverse events including hypersensitivity syndrome reaction (HSR), serum sicknesslike reaction (SSLR), and drug-induced lupus, a follow-up study based on a retrospective review of our Drug Safety Clinic and the Health Protection Branch databases and a literature review was conducted to determine if similar rare events are associated with tetracycline and doxycycline. Cases of isolated single organ dysfunction (SOD) attributable to the use of these antibiotics also were identified.

METHODS

Nineteen cases of HSR due to minocycline, 2 due to tetracycline, and 1 due to doxycycline were identified. Eleven cases of SSLR due to minocycline, 3 due to tetracycline, and 2 due to doxycycline were identified. All 33 cases of drug-induced lupus were attributable to minocycline. Forty cases of SOD from minocycline, 37 cases from tetracycline, and 6 from doxycycline were detected. Hypersensitivity syndrome reaction, SSLR, and SOD occur on average within 4 weeks of therapy, whereas minocycline-induced lupus occurs on average 2 years after the initiation of therapy.

CONCLUSIONS

Early serious events occurring during the course of tetracycline antibiotic treatment include HSR, SSLR, and SOD. Drug-induced lupus, which occurs late in the course of therapy, is reported only with minocycline. We theorize that minocycline metabolism may account for the increased frequency of serious adverse events with this drug.

BACKGROUND

Quercetin is known to possess beneficial effects in ameliorating diabetic complications, however the mechanisms underlying cardioprotective effect of this compound in diabetes is not fully revealed. In this study, quercetin effect on oxidative stress, inflammation and apoptosis in the heart in diabetes were investigated. Normal and streptozotocin-nicotinamide induced adult male diabetic rats received quercetin (10, 25 and 50mg/kg/bw) orally for 28days were anesthetized and hemodynamic parameters i.e. systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were measured. Blood was collected for analyses of fasting glucose (FBG), insulin and cardiac injury marker levels (troponin-C, CK-MB and LDH). Following sacrificed, heart was harvested and histopathological changes were observed. Heart was subjected for analyses of oxidative stress marker i.e. lipid peroxidation and activity and expression levels of anti-oxidative enzymes i.e. <em>SOD</em>, CAT and GPx. Levels of inflammation in the heart were determined by measuring nuclear factor (p65-NF-κB), tumor necrosis factor (TNF-α), interleukins (IL)-1β and IL-6 levels by using enzyme-linked immunoassay (ELISA). Distribution and expression levels of TNF-α and Ikk-β (inflammatory markers), caspase-<em>3</em>, caspase-9, Blc-2 and Bax (apoptosis markers) in the heart were identified by immunohistochemistry and Western blotting respectively.

RESULTS

Administration of quercetin to diabetic rats caused significant decrease in FBG and cardiac injury marker levels with increased in insulin levels. In diabetic rat heart, lesser histopathological changes were observed with oxidative stress, inflammation and apoptosis levels markedly decreased.

CONCLUSIONS

Quercetin could potentially be used to ameliorate myocardial damage due to oxidative stress, inflammation and apoptosis in diabetes.

Quercetin has been demonstrated to play an important role in altering the progression of ischemic brain injuries and neurodegenerative diseases by protecting against oxidative stress. The effects of quercetin on brain damage after subarachnoid hemorrhage (SAH), however, have not been investigated. This study was designed to explore the effects of quercetin on oxidative stress and brain edema after experimental SAH using four equal groups (n = 16) of adult male Sprague-Dawley (SD) rats, including a sham group, an SAH + vehicle group, an SAH + quercetin10 group, and an SAH + quercetin50 group. The rat SAH model was induced by injection of 0.<em>3</em> ml of non-heparinised arterial blood into the prechiasmatic cistern. In the SAH + quercetin10 and SAH + quercetin50 groups, doses of 10 mg/kg and 50 mg/kg quercetin, respectively, were directly administered by intraperitoneal injection at <em>3</em>0 min, 12 h, and 24 h after SAH induction. Cerebral tissue samples were extracted for enzymatic antioxidant determination, lipid peroxidation assay, caspase-<em>3</em> activity and water content testing 48 h after SAH. Treatment with a high dose (50 mg/kg) of quercetin markedly enhanced the activities of copper/zinc superoxide dismutase (CuZn-<em>SOD</em>) and glutathione peroxidase (GSH-Px), and treatment with this dose significantly reduced the level of malondialdehyde (MDA). Caspase-<em>3</em> and brain edema was ameliorated and neurobehavioral deficits improved in rats that received the high dose of quercetin. The findings suggest that the early administration of optimal dose of quercetin may ameliorate brain damage and provide neuroprotection in the SAH model, potentially by enhancing the activity of endogenous antioxidant enzymes and inhibiting free radical generation.

The present study was designed to probe the effects of Huperzine A (HupA) on diabetes-associated cognitive decline (DACD) using a streptozotocin (STZ)-injected rat model. Diabetic rats were treated with HupA (0.05 and 0.1 mg/kg) for seven weeks. Memory functions were evaluated by the water maze test. Nissl staining was selected for detecting neuronal loss. Protein and mRNA levels of brain-derived neurotrophic factor (BDNF) were analyzed by ELISA and real-time PCR, respectively. The activities of choline acetylase (ChAT), Acetylcholinesterase (AChE), malondialdehyde (MDA), superoxide dismutase (<em>SOD</em>), glutathione peroxidase (GSH-Px), catalase (CAT), NF-κB p65 unit, TNF-α, IL-1β, IL-6 and caspase-<em>3</em> were measured using corresponding kits. After seven weeks, diabetic rats exhibited remarkable reductions in: body weight, percentage of time spent in target quadrant, number of times crossing the platform, ChAT and BDNF levels, <em>SOD</em>, GSH-Px and CAT accompanied with increases in neuronal damage, plasma glucose levels, escape latency, mean path length, AChE, MDA level as well as CAT, NF-κB p65 unit, TNF-α, IL-1β, IL-6 and caspase-<em>3</em> in cerebral cortex and hippocampus. Supplementation with HupA significantly and dose-dependently reversed the corresponding values in diabetes. It is concluded that HupA ameliorates DACD via modulating BDNF, oxidative stress, inflammation and apoptosis.

New Mn(II) macrocyclic pentaamine complexes derived from the biscyclohexyl-pyridine complex, M4040<em>3</em> ([manganese(II)dichloro[(4R,9R,14R,19R)-<em>3</em>,10,1<em>3</em>,20,26-pentaazatetracyclo[20.<em>3</em>.1.0.(4,9)0(14,19)]hexacosa-1(26),-22(2<em>3</em>),24-triene]]), are described here. The complex M4040<em>3</em> was previously shown to be a superoxide dismutase (<em>SOD</em>) catalyst with rates for the catalytic dismutation of superoxide to oxygen and hydrogen peroxide at pH = 7.4 of 1.2 x 10(+7) M(-1) s(-1).(1) The use of the computer-aided design paradigm reported previously for this class of Mn(II) complexes(2,<em>3</em>) led to the prediction that the 2S,21S-dimethyl derivative of M4040<em>3</em> should possess superior catalytic <em>SOD</em> activity. The synthesis of this new macrocyclic Mn(II) complex, [manganese(II)dichloro[2S, 21S-dimethyl-(4R,9R,14R,19R)-<em>3</em>,10,1<em>3</em>,20,26-pentaazatetracyclo[20.<em>3</em>.1.0.(4,9)0(14,19)]hexacosa-1(26),22(2<em>3</em>),24-triene]], 5, was accomplished via a high yield template condensation utilizing the linear tetraamine, N,N'-Bis[(1R,2R)-[2-(amino)]cyclohexyl]-1,2-diaminoethane, 1, 2,6-diacetylpyridine, and MnCl(2) to form the macrocyclic diimine complex, 2, which then is reduced. The two other possible dimethyl diastereomers of 5 (2R,21R-dimethyl,<em>3</em>, and 2R,21S-dimethyl, 6) were also prepared via reduction of the diimine complex 2. Two of these complexes, <em>3</em> and 5, were characterized by X-ray structure determination confirming their absolute stereochemistry as 2R,21R-dimethyl and 2S,21S-dimethyl, respectively. The results of the MM calculations which predict that the 2S,21S-dimethyl complex, 5, should be a high activity catalyst and that the 2R,21R-dimethyl complex, <em>3</em>, should have little or no catalytic activity are presented. The catalytic <em>SOD</em> rates for these complexes are reported for each of these complexes and a correlation with the modeling predictions is established showing that 2R,21R-complex, <em>3</em>, has no measurable catalytic rate, while the 2R,21S complex, 6, is identical to M4040<em>3</em>, and the 2S,21S- complex, 5, possesses a very fast rate at pH = 7.4 of 1.6 x 10(+9) M(-1) s(-1) exceeding that of the native mitochondrial Mn<em>SOD</em> enzymes.