Pentahydroxy flavonoid isolated from Madhuca indica ameliorated adjuvant-induced arthritis via modulation of inflammatory pathways.

Rheumatoid arthritis (RA) is an autoimmune disease associated with advanced joint dysfunction. Madhuca indica J. F. Gmel, from the family Sapotaceae, is an Indian medicinal plant reported to have an array of pharmacological properties. The aim of present investigation was to determine the anti-arthritic potential of an isolated phytoconstituent from methanolic leaf extract of Madhuca indica (MI-ALC) against FCA-induced experimental arthritis. Polyarthritis was induced in female rats (strain: Wistar) via an intradermal injection of FCA (0.1 mL) into the tail. Polyarthritis developed after 32 days of FCA administration. Then rats were treated orally with an isolated phytoconstituent from MI-ALC at doses of 5, 10, and 20 mg/kg. Findings suggested that High-Performance Thin-Layer Chromatography, Fourier-Transform Infrared Spectroscopy, and Liquid Chromatography-Mass Spectrometry spectral analyses of the phytoconstituent isolated from MI-ALC confirmed the structure as 3,5,7,3',4'-Pentahydroxy flavone (i.e., QTN). Treatment with QTN (10 and 20 mg/kg) showed significant (p < 0.05) inhibition of increased joint diameter, paw volume, paw withdrawal threshold, and latency. The elevated synovial oxidative stress (Superoxide dismutase, reduced glutathione, and malondialdehyde) and protein levels of Tumor necrosis factor-α (TNF-α) and Interleukin (ILs) were markedly (p < 0.05) reduced by QTN. It also effectively (p < 0.05) ameliorated cyclooxygenase-2 (COX-2), Nuclear factor of kappa light polypeptide gene enhancer in B cells (NF-kß) and its inhibitor-α (Ikßα), and ATP-activated P2 purinergic receptors (P2X7) protein expressions as determined by western blot analysis. In conclusion, QTN ameliorates FCA-induced hyperalgesia through modulation of elevated inflammatory release (NF-kß, Ikßα, P2X7, and COX-2), oxido-nitrosative stress, and pro-inflammatory cytokines (ILs and TNF-α) in experimental rats.

Compound XiongShao Capsule ameliorates streptozotocin-induced diabetic peripheral neuropathy in rats via inhibiting apoptosis, oxidative - nitrosative stress and advanced glycation end products.

ETHNOPHARMACOLOGICAL RELEVANCE: Compound XiongShao Capsule (CXSC), a traditional herb formula, has been approved for using to treat diabetic peripheral neuropathy (DPN) by the Shanghai Food and Drug Administration, with significant efficacy in clinic. AIM OF THE STUDY: This study aimed to investigate the multidimensional pharmacological mechanisms and synergism of CXSC against DPN in rats. METHODS: The quality analysis of CXSC was performed by high-performance liquid chromatography (HPLC) and thin-layer chromatography. Rats with DPNinduced by streptozotocin/high-fat diet for 4 weeks were treated with CXSC at three doses (1.2 g/kg, 0.36 g/kg, and 0.12 g/kg), or epalrestat (15 mg/kg) daily for 8 weeks continuously. During the treatment period, body weight, serum glucose levels, and nerve function, including nerve conduction velocity (NCV), and mechanical and thermal hyperalgesia were tested and assessed every 4 weeks. In the 13th week, the histopathological examination in the sciatic nerve was performed using a transmission electron microscope. The expression of apoptosis-related proteins of BAX, BCL2, and caspase-3 in the sciatic nerve was examined using hematoxylin and eosin staining. The serum levels of advanced glycation end products (AGEs), oxidative-nitrosative stress biomarkers of superoxide dismutase (SOD), and nitric oxide synthase (NOS) were measured using a rat-specific ELISA kit. RESULTS: CXSC had no significant effect on body weight or serum glucose levels (P > 0.05), but it significantly improved mechanical hyperalgesia (F5,36 = 18.24, P < 0.0001), thermal hyperalgesia (F5,36 = 8.45, P < 0.0001), and NCV (motor NCV: F5,36 = 7.644, P < 0.0001, sensory NCV: F5,36 = 12.83, P < 0.0001). Besides, it maintained myelin and axonal structure integrity, downregulated the expression of apoptosis-related proteins in the sciatic nerve tissue, reduced AGEs and NOS levels, and enhanced antioxidant enzyme SOD activities in the serum. CONCLUSION: CXSC exerted neuroprotective effects against rats with DPN through multidimensional pharmacological mechanisms including antiapoptotic activity in the sciatic nerve and downregulation of the level of serum NOS, SOD and AGEs.

Effect of concomitant treatment of curcumin and melatonin on cisplatin-induced nephrotoxicity in rats.

Cisplatin (CP) is a potent anticancer drug used to treat solid tumors. Its use, however, is dose-limited by its nephrotoxicity. We aimed to compare the effect of melatonin and curcumin given singly, with that of a combination of these two agents on CP-induced nephrotoxicity in rats. CP (6 mg/kg, given once intraperitoneally) induced nephrotoxicity as evidenced by several significant adverse physiological, biochemical and histopathological actions that included a reduction in body weight, increased urine production, and significant alterations in some conventional and novel renal damage indices in plasma, urine and kidneys. CP also elevated several pro-inflammatory cytokines and caused renal oxidative/nitrosative stress. Supplementation with either curcumin (200 mg/kg) or melatonin (10 mg /kg) given singly by oral gavage for eight consecutive days prior to CP injection and four days thereafter, significantly mitigated the adverse renal effects of CP, by attenuating the pro-inflammatory and apoptotic mediators and improving antioxidant competence in renal tissues of CP- treated rats. When curcumin and melatonin were given together, the ameliorative effect was augmented in some of the measured indices e.g. tumor necrosis factor alpha, cystatin C, uric acid, phosphorus in plasma and, urine creatinine and creatinine clearance. Renal platinum concertation was reduced more with curcumin than that with melatonin, while the reduction was maximized when both melatonin and curcumin were given. Pending further pharmacological and toxicological studies, a combination of these two agents is likely to be mor effective in mitigating the adverse renal effects of CP administered to cancer patients.

Nephro-protective activity of wheatgrass juice against alcohol-induced oxidative damage in rats.

The present study is an attempt to check the protective effect of fresh wheatgrass juice (WJ) as a potential therapeutic agent against alcohol-induced oxidative/nitrosative stress leading to nephrotoxicity in rats. Administration of 20% ethanol (5 g/kg b.wt/day) for 60 days resulted in a significant rise in the plasma concentrations of urea and creatinine with decreased levels of uric acid. Besides, a significant decrease in plasma electrolyte/mineral levels along with decreased activity of Na+/K+-ATPase activity was recorded in alcohol administered rats. In alcohol administered rats augmented lipid peroxidation (thio-barbituric acid reactive substance - TBARS) and nitric oxide (NOx) reflects the increased oxidative stress and nitrosative stress, moreover, we noticed a concomitant decrease in the levels of reduced glutathione (GSH) with decreased activities of antioxidant enzyme machinery viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione s-transferase (GST). Administration of WJ to the alcoholic rats significantly restored the plasma biochemical markers and the kidney antioxidant status near to control group animal levels. These findings were further confirmed by the kidney histopathological studies, wherein the protective effect of WJ treatment in retaining the morphological features of the renal tissue in spite of the alcohol administration was evident. The rich repertoire of phenolic compounds present in the WJ from the freshly sprouted seeds synergistically protected the kidney from alcohol-induced damage.

The Venom of Philippine Tarantula (Theraphosidae) Contains Peptides with Pro-Oxidative and Nitrosative-Dependent Cytotoxic Activities against Breast Cancer Cells (MCF-7) In Vitro.

BACKGROUND: Breast cancer is a multifactorial disease that affects women worldwide. Its progression is likely to be executed by oxidative stress wherein elevated levels of reactive oxygen and nitrogen species drive several breast cancer pathologies. Spider venom contains various pharmacological peptides which exhibit selective activity to abnormal expression of ion channels on cancer cell surface which can confer potent anti-cancer activities against this disease. METHODS: Venom was extracted from a Philippine tarantula by electrostimulation and fractionated by reverse phase-high performance liquid chromatography (RP-HPLC). Venom fractions were collected and used for in vitro analyses such as cellular toxicity, morphological assessment, and oxidative stress levels. RESULTS: The fractionation of crude spider venom generated several peaks which were predominantly detected spectrophotometrically and colorimetrically as peptides. Treatment of MCF-7 cell line of selected spider venom peptides induced production of several endogenous radicals such as hydroxyl radicals (•OH), nitric oxide radicals (•NO), superoxide anion radicals (•O2-) and lipid peroxides via malondialdehyde (MDA) reaction, which is comparable with the scavenging effects afforded by 400 µg/mL vitamin E and L-cysteine (p<0.05). Concomitantly, the free radicals produced decrease the mitochondrial membrane potential and metabolic activity as detected by rhodamine 123 and tetrazolium dye respectively (p>0.05). This is manifested by cytotoxicity in MCF-7 cells as seen by increase in membrane blebbing, cellular detachment, caspase activity and nuclear fragmentation. CONCLUSION: These data suggest that the Philippine tarantula venom contains peptide constituents exhibiting pro-oxidative and nitrosative-dependent cytotoxic activities against MCF-7 cells and can indicate mechanistic insights to further explore its potential application as prooxidants in cancer therapy.
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Coriandrum sativum improve neuronal function via inhibition of oxidative/nitrosative stress and TNF-α in diabetic neuropathic rats.

ETHNOPHRAMACOLOGICAL RELEVANCE: Coriandrum sativum L. is traditionally acknowledged for its use in inflammatory disorders, altered blood lipid levels, respiratory and digestive problems. AIM OF THE STUDY: The present study investigates possible role of hydro-alcoholic extract of C. sativum (CHA) seeds in the attenuation of indices of diabetic peripheral neuropathy (DPN). MATERIALS AND METHODS: Phytochemical analysis was carried out by employing chromatographic, spectroscopic as well as spectrometric techniques. Diabetes was induced by a single i.p. injection of freshly prepared STZ (65 mg/kg). The indexed markers of DPN, i.e., thermal and mechanical hyperalgesia were found to be prominent on the 60th day of STZ administration. Administration of CHA (100, 200, and 400 mg/kg, p.o.) for 30 days was started on the substantiation of DPN onset. Molecular docking study was performed by targeting TNF-α. RESULTS: Phytochemical analysis revealed the presence of flavonoids, terpenoids, and phenolic acids. Oral administration of CHA considerably attenuated hyperglycemia and decreased pain threshold in diabetic rats as well as modulated oxidative-nitrosative stress. Docking study suggested good affinity of flavonoids when docked into the binding site of TNF-α. CONCLUSION: In conclusion, using STZ model, it was successfully predicted that CHA might be beneficial in diabetes-induced neuropathic pain by inhibiting oxidative/nitrosative stress and inflammatory cytokine.

Therapeutic targets of oxidative/nitrosative stress and neuroinflammation in ischemic stroke: Applications for natural product efficacy with omics and systemic biology.

Oxidative/nitrosative stress and neuroinflammation are critical pathological processes in cerebral ischemia-reperfusion injury, and their intimate interactions mediate neuronal damage, blood-brain barrier (BBB) damage and hemorrhagic transformation (HT) during ischemic stroke. We review current progress towards understanding the interactions of oxidative/nitrosative stress and inflammatory responses in ischemic brain injury. The interactions between reactive oxygen species (ROS)/reactive nitrogen species (RNS) and innate immune receptors such as TLR2/4, NOD-like receptor, RAGE, and scavenger receptors are crucial pathological mechanisms that amplify brain damage during cerebral ischemic injury. Furthermore, we review the current progress of omics and systematic biology approaches for studying complex network regulations related to oxidative/nitrosative stress and inflammation in the pathology of ischemic stroke. Targeting oxidative/nitrosative stress and neuroinflammation could be a promising therapeutic strategy for ischemic stroke treatment. We then review recent advances in discovering compounds from medicinal herbs with the bioactivities of simultaneously regulating oxidative/nitrosative stress and pro-inflammatory molecules for minimizing ischemic brain injury. These compounds include sesamin, baicalin, salvianolic acid A, 6-paradol, silymarin, apocynin, 3H-1,2-Dithiole-3-thione, (-)-epicatechin, rutin, Dl-3-N-butylphthalide, and naringin. We finally summarize recent developments of the omics and systematic biology approaches for exploring the molecular mechanisms and active compounds of Traditional Chinese Medicine (TCM) formulae with the properties of antioxidant and anti-inflammation for neuroprotection. The comprehensive omics and systematic biology approaches provide powerful tools for exploring therapeutic principles of TCM formulae and developing precision medicine for stroke treatment.

A novel pyrazole-containing selenium compound modulates the oxidative and nitrergic pathways to reverse the depression-pain syndrome in mice.

Bearing in mind that pain and major depressive disorder (MDD) often share biological pathways, this condition is classified as depression-pain syndrome. Mounting evidence suggests that oxidative stress is implicated in the pathophysiology of this syndrome. The development of effective pharmacological interventions for the depression-pain syndrome is of particular importance as clinical treatments for this comorbidity have shown limited efficacy. Therefore, the present study aimed to evaluate whether the 3,5-dimethyl-1-phenyl-4-(phenylselanyl)-1H-pyrazole (SePy) was able to reverse the depression-pain syndrome induced by intracerebroventricular (i.c.v) streptozotocin (STZ) in mice and the possible modulation of oxidative and nitrergic pathways in its effect. The treatment with SePy (1 and 10 mg/kg) administered intragastrically (i.g.) reversed the increased immobility time in the tail suspension test, decreased grooming time in the splash test, latency time to nociceptive response in the hot plate test, and the response frequency of Von Frey hair (VFH) stimulation induced by STZ (0.2 mg/4 µl/per mouse). Additionally, SePy (10 mg/kg, i.g.) reversed STZ-induced alterations in the levels of reactive oxygen species, nitric oxide, and lipid peroxidation and the superoxide dismutase and catalase activities in the prefrontal cortices (PFC) and hippocampi (HC) of mice. Treatment with SePy (10 mg/kg, i.g.) also reversed the STZ-induced increased expression of inducible nitric oxide synthase (iNOS) and glycogen synthase kinase 3 beta (GSK3ß) in the PFC and HC. An additional molecular docking investigation found that SePy binds to the active site of iNOS and GSK3ß. Altogether, these results indicate that the antidepressant-like effect of SePy is accompanied by decreased hyperalgesia and mechanical allodynia, which were associated with its antioxidant effect.

The Effect of N-Acetylcysteine on Respiratory Enzymes, ADP/ATP Ratio, Glutathione Metabolism, and Nitrosative Stress in the Salivary Gland Mitochondria of Insulin Resistant Rats.

This is the first study to assess the effect of N-acetylcysteine (NAC) on the mitochondrial respiratory system, as well as free radical production, glutathione metabolism, nitrosative stress, and apoptosis in the salivary gland mitochondria of rats with high-fat diet (HFD)-induced insulin resistance (IR). The study was conducted on male Wistar rats divided into four groups of 10 animals each: C (control, rats fed a standard diet containing 10.3% fat), C + NAC (rats fed a standard diet, receiving NAC intragastrically), HFD (rats fed a high-fat diet containing 59.8% fat), and HFD + NAC (rats fed HFD diet, receiving NAC intragastrically). We confirmed that 8 weeks of HFD induces systemic IR as well as disturbances in mitochondrial complexes of the parotid and submandibular glands of rats. NAC supplementation leads to a significant increase in the activity of complex I, II + III and cytochrome c oxidase (COX), and also reduces the ADP/ATP ratio compared to HFD rats. Furthermore, NAC reduces the hydrogen peroxide production/activity of pro-oxidant enzymes, increases the pool of mitochondrial glutathione, and prevents cytokine formation, apoptosis, and nitrosative damage to the mitochondria in both aforementioned salivary glands of HFD rats. To sum up, NAC supplementation enhances energy metabolism in the salivary glands of IR rats, and prevents inflammation, apoptosis, and nitrosative stress.

Myalgic encephalomyelitis/chronic fatigue syndrome: From pathophysiological insights to novel therapeutic opportunities.

Myalgic encephalomyelitis (ME) or chronic fatigue syndrome (CFS) is a common and disabling condition with a paucity of effective and evidence-based therapies, reflecting a major unmet need. Cognitive behavioural therapy and graded exercise are of modest benefit for only some ME/CFS patients, and many sufferers report aggravation of symptoms of fatigue with exercise. The presence of a multiplicity of pathophysiological abnormalities in at least the subgroup of people with ME/CFS diagnosed with the current international consensus "Fukuda" criteria, points to numerous potential therapeutic targets. Such abnormalities include extensive data showing that at least a subgroup has a pro-inflammatory state, increased oxidative and nitrosative stress, disruption of gut mucosal barriers and mitochondrial dysfunction together with dysregulated bioenergetics. In this paper, these pathways are summarised, and data regarding promising therapeutic options that target these pathways are highlighted; they include coenzyme Q10, melatonin, curcumin, molecular hydrogen and N-acetylcysteine. These data are promising yet preliminary, suggesting hopeful avenues to address this major unmet burden of illness.

Repeated administration of a selenium-containing indolyl compound attenuates behavioural alterations by streptozotocin through modulation of oxidative stress in mice.

Although the pathophysiology of major depression disorder (MDD) is still poorly understood, mounting evidence suggests that the brains of depressed patients are under oxidative stress, leading to depressive symptoms that may include anxiety and cognitive impairment. This study aimed to investigate if the seleno-organic compound 1-methyl-3-(phenylselanyl)-1H-indole (MFSeI) reverses the depression- and anxiogenic-like behaviour, cognitive impairment and oxidative stress induced by the intra-cerebroventricular injection of streptozotocin (STZ; 0.2 mg/4 µl/per mouse) in Swiss male mice. Twenty-four hours after the STZ injection, mice were treated with MFSeI (10 mg/kg, intra-gastrically), or vehicle solution, once daily for seven days. The behavioural tests were performed 30 min after the final MFSeI administration, followed by euthanasia and collection of the cerebral cortex and hippocampus. Administration of MFSeI reversed the depression- and anxiogenic-like behaviour and cognitive impairment induced by STZ, in mice. Neurochemical analyses demonstrated that MFSeI reversed the STZ-increased levels of reactive species, nitrite, lipid peroxidation and acetylcholinesterase activity in the cerebral cortex and hippocampus of mice. Moreover, a single administration of MFSeI (300 mg/kg, intra-gastrically) did not cause acute toxicity in Swiss male mice. Altogether, our data suggest that MFSeI exhibits antidepressant- and anxiolytic-like effects and improves the cognition of STZ-treated mice, without any toxicity.

Antioxidant effects of curcumin in models of neurodegeneration, aging, oxidative and nitrosative stress: A review.

The global burden of neurodegenerative disorders has increased substantially over the past 2 decades due to rising rates of population aging. Although neurodegenerative disorders differ in their clinical presentation, the underlying pathobiological processes are largely shared. Oxidative stress, among other mechanisms, is strongly implicated in neurodegenerative disorders and aging, and can potentially be targeted by antioxidative agents. Curcumin, a component of turmeric, is a compound that has received considerable attention for its therapeutic properties, and it is considered to be a powerful antioxidant. In this review, we analyzed the evidence for curcumin as an antioxidant in models of neurodegenerative disorders as well as oxido-nitrosative stress. A total of 1451 articles were found from 3 scientific literature databases (PubMed, Scopus, and Web of Science). After all exclusions, a final total of 64 articles were included in this review. The majority of the studies showed that curcumin, or derivatives thereof, were protective against oxidative and/or nitrosative stress in various cellular and animal models. Overall, curcumin protected against lipid and protein oxidation with a reduction in levels of malondialdehyde, and protein carbonyls, thiols and nitrotyrosines. Furthermore, it stimulated the activities of antioxidant enzymes such as superoxide dismutase and glutathione peroxidase. In conclusion, curcumin appears to be a promising compound for phytomedicine. However, due to some concerns about its efficacy, further targeted experiments are needed to identify its exact molecular targets and pathways responsible for its antioxidant effects.

Cupuaçu extract reduces nitrosative stress and modulates inflammatory mediators in the kidneys of experimental diabetes.

BACKGROUND & AIMS: We have previously reported an increased nitrosative stress in the kidneys of diabetic animals, which was reduced by an antioxidant probiotic. The present study evaluated whether the extract of cupuaçu (EC), an antioxidant compound rich in polyphenols and theograndins, when administered at a dose that can be reasonably obtained through daily consumption, could delay the onset of diabetic complications in the kidney. METHODS: Mouse immortalized mesangial cells (MiMC) were placed in medium normal glucose (NG) or high glucose (HG), with or without EC (500, 100, 50 or 10 µg/mL) during 24, 48 or 72 h for analysis of viability, proliferation, nitric oxide (NO) levels and reactive oxygen species or nitrogen (ROS/RNS). Male, adult Wistar rats were distributed in 4 groups: control (CTL) and diabetic (DM) who received water; CTLEC and DMEC who received 1 mL/day of EC (1 g/mL), via gavage for 8 consecutive weeks. After, metabolic profile and renal function were evaluated and, kidneys were collected for analysis of NO, ROS, 3-nitrotyrosine (3-NT), endothelial nitric oxide synthase (eNOS), IL-6, IL-10, TNF-α and NF-κB p65. RESULTS: The MiMC showed normal viability in all groups, demonstrating that EC had no cytotoxic effect at doses on 24, 48 or 72 h. MiMC under HG presented significant increase in proliferation, NO and ROS vs. NG; these parameters were significantly reduced after 72 h of EC treatment (P < 0.05). DMEC showed a significant reduction of feed intake, ROS and NO, 3-NT, IL-6 and eNOS vs. DM (P < 0.05). Supplementation with EC at a dose consumed daily could improve control of nitrosative stress, combined with reduction of inflammatory factors, suggesting the importance of bioactive compounds as non-pharmacological adjuvant therapy to delay kidney complications in diabetic patients.

Radicals, Oxidative/Nitrosative Stress and Preeclampsia.

Preeclampsia (PE) has a profound effect in increasing both maternal and fetal morbidity and mortality especially in third World. Disturbances of extravillous trophoblast migration toward uterine spiral arteries is characteristic feature of PE, which, in turn, leads to increased uteroplacental vascular resistance and by vascular dysfunction resulting in reduced systemic vasodilatory properties. Underlying pathogenesis appeared to be an altered bioavailability of nitric oxide (NO•) and tissue damage caused by increased levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS). The increase in ROS and RNS production or the decrease in antioxidant mechanisms generates a condition called oxidative and nitrosative stress, respectively, defined as the imbalance between pro- and antioxidants in favor of the oxidants. Additionally, ROS might trigger platelet adhesion and aggregation leading to intravascular coagulopathy. ROS-induced coagulopathy causes placental infarction and impairs the uteroplacental blood flow in PE. As a consequence of these disorders could result in deficiencies in oxygen and nutrients required for normal fetal development resulting in fetal growth restriction. On the one hand, enzymatic and nonenzymatic antioxidants scavenge ROS and protect tissues against oxidative damage. More specifically, placental antioxidant enzymes including catalase, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) protect the vasculature from ROS, maintaining the vascular function. On the other hand, ischemia in placenta in PE reduces the antioxidant activity. Collectively, the extent of oxidative stress would increase and therefore leads to the development of the pathological findings of PE including hypertension and proteinuria. Our goal in this article is to review current literature about researches demonstrating the interplay between oxidative, nitrosative stresses and PE, about their roles in the pathophysiology of PE and also about the outcomes of current clinical trials aiming to prevent PE with antioxidant supplementation.

Oxidative Imbalance, Nitrative Stress, and Inflammation in C6 Glial Cells Exposed to Hexacosanoic Acid: Protective Effect of N-acetyl-L-cysteine, Trolox, and Rosuvastatin.

X-linked adrenoleukodystrophy (X-ALD) is an inherited neurometabolic disorder caused by disfunction of the ABCD1 gene, which encodes a peroxisomal protein responsible for the transport of the very long-chain fatty acids from the cytosol into the peroxisome, to undergo ß-oxidation. The mainly accumulated saturated fatty acids are hexacosanoic acid (C26:0) and tetracosanoic acid (C24:0) in tissues and body fluids. This peroxisomal disorder occurs in at least 1 out of 20,000 births. Considering that pathophysiology of this disease is not well characterized yet, and glial cells are widely used in studies of protective mechanisms against neuronal oxidative stress, we investigated oxidative damages and inflammatory effects of vesicles containing lecithin and C26:0, as well as the protection conferred by N-acetyl-L-cysteine (NAC), trolox (TRO), and rosuvastatin (RSV) was assessed. It was verified that glial cells exposed to C26:0 presented oxidative DNA damage (measured by comet assay and endonuclease III repair enzyme), enzymatic oxidative imbalance (high catalase activity), nitrative stress [increased nitric oxide (NO) levels], inflammation [high Interleukin-1beta (IL-1ß) levels], and induced lipid peroxidation (increased isoprostane levels) compared to native glial cells without C26:0 exposure. Furthermore, NAC, TRO, and RSV were capable to mitigate some damages caused by the C26:0 in glial cells. The present work yields experimental evidence that inflammation, oxidative, and nitrative stress may be induced by hexacosanoic acid, the main accumulated metabolite in X-ALD, and that antioxidants might be considered as an adjuvant therapy for this severe neurometabolic disease.

Combination ART-Induced Oxidative/Nitrosative Stress, Neurogenic Inflammation and Cardiac Dysfunction in HIV-1 Transgenic (Tg) Rats: Protection by Mg.

Chronic effects of a combination antiretroviral therapy (cART = tenofovir/emtricitatine + atazanavir/ritonavir) on systemic and cardiac oxidative stress/injury in HIV-1 transgenic (Tg) rats and protection by Mg-supplementation were assessed. cART (low doses) elicited no significant effects in normal rats, but induced time-dependent oxidative/nitrosative stresses: 2.64-fold increased plasma 8-isoprostane, 2.0-fold higher RBC oxidized glutathione (GSSG), 3.2-fold increased plasma 3-nitrotyrosine (NT), and 3-fold elevated basal neutrophil superoxide activity in Tg rats. Increased NT staining occurred within cART-treated HIV-Tg hearts, and significant decreases in cardiac systolic and diastolic contractile function occurred at 12 and 18 weeks. HIV-1 expression alone caused modest levels of oxidative stress and cardiac dysfunction. Significantly, cART caused up to 24% decreases in circulating Mg in HIV-1-Tg rats, associated with elevated renal NT staining, increased creatinine and urea levels, and elevated plasma substance P levels. Strikingly, Mg-supplementation (6-fold) suppressed all oxidative/nitrosative stress indices in the blood, heart and kidney and substantially attenuated contractile dysfunction (>75%) of cART-treated Tg rats. In conclusion, cART caused significant renal and cardiac oxidative/nitrosative stress/injury in Tg-rats, leading to renal Mg wasting and hypomagnesemia, triggering substance P-dependent neurogenic inflammation and cardiac dysfunction. These events were effectively attenuated by Mg-supplementation likely due to its substance P-suppressing and Mg's intrinsic anti-peroxidative/anti-calcium properties.

Andrographolide ameliorates silica induced pulmonary fibrosis.

The purpose of this study was to investigate the protective effect of andrographolide in silica-induced pulmonary fibrosis (PF) in mice and its underlying mechanisms. Male Swiss albino mice were divided into five groups: Normal control group, disease control group (1.5 mg silica/60 µL/mice) via oropharyngeal route, low dose (LD) group received silica + andrographolide (3 mg/kg), high dose (HD) group received silica + andrographolide (10 mg/kg), andrographolide per se group received 10 mg/kg andrographolide. Various bronchoalveolar lavage fluid (BALF) and biochemical parameters, inflammatory cytokines, histology and protein expression studies were carried out. Andrographolide significantly reduced total protein concentration, albumin, accumulation of inflammatory cells and lactate dehydrogenase (LDH) level in BALF. We found that andrographolide intervention led to decreased levels of the inflammatory cells including neutrophils, macrophages and lymphocytes in the BALF of the treated animals. In addition, andrographolide significantly reduced nitrite (p < 0.01 at HD), malondialdehyde (p < 0.01 at HD) and upregulated glutathione (p < 0.01 at HD) in silica challenged animals. Andrographolide showed anti-fibrotic activity by reducing collagen deposition and inflammation in lung. Histopathology revealed that andrographolide decreased irregular cellular nodules, inflammatory infiltration and fibrosis. Andrographolide intervention significantly reduced the expression of N-cadherin, α-SMA and vimentin (mesenchymal markers) and upregulated the expression of E-cadherin (an epithelial marker). Hence, andrographolide elicits its anti-pulmonary fibrotic effect by halting the progression of epithelial-to-mesenchymal transition (EMT) via affecting fibroblasts. We, to the best of our knowledge prove for the first time that andrographolide possesses potent antifibrotic activity by targeting inflammatory cells and EMT associated fibroblasts.

Targeting Phosphodiesterase-5 by Vardenafil Improves Vascular Graft Function.

OBJECTIVES: Ischaemia reperfusion (IR) injury occurs during vascular graft harvesting and implantation during vascular/cardiac surgery. Elevated intracellular cyclic guanosine monophosphate (cGMP) levels contribute to an effective endothelial protection in different pathophysiological conditions. The hypothesis that the phosphodiesterase-5 inhibitor vardenafil would protect vascular grafts against IR injury by upregulating the nitric oxide-cGMP pathway in the vessel wall of the bypass graft was investigated. METHODS: Lewis rats (n = 6-7/group) were divided into Group 1, control; Group 2, donor rats received intravenous saline; Group 3, received intravenous vardenafil (30 µg/kg) 2 h before explantation. Whereas aortic arches of Group 1 were immediately mounted in an organ bath, aortic segments of Groups 2 and 3 were stored for 2 h in saline and transplanted into the abdominal aorta of the recipient. Two hours after transplantation, the implanted grafts were harvested. Endothelium dependent and independent vasorelaxations were investigated. TUNEL, CD-31, ICAM-1, VCAM-1, α-SMA, nitrotyrosine, dihydroethidium and cGMP immunochemistry were also performed. RESULTS: Compared with the control, the saline group showed significantly attenuated endothelium dependent maximal relaxation (Rmax) 2 h after reperfusion, which was significantly improved by vardenafil supplementation (Rmax control, 91 ± 2%; saline 22 ± 2% vs. vardenafil 39 ± 4%, p < .001). Vardenafil pre-treatment significantly reduced DNA fragmentation (control 9 ± 1%, saline 66 ± 8% vs. vardenafil 13 ± 1%, p < .001), nitro-oxidative stress (control 0.8 ± 0.3, saline 7.6 ± 1.3 vs. vardenafil 3.8 ± 1, p = .036), reactive oxygen species level (vardenafil 36 ± 4, control 34 ± 2 vs. saline 43 ± 2, p = .049), prevented vascular smooth muscle cell damage (control 8.5 ± 0.7, saline 4.3 ± 0.6 vs. vardenafil 6.7 ± 0.6, p = .013), decreased ICAM-1 (control 4.1 ± 0.5, saline 7.0 ± 0.9 vs. vardenafil 4.4 ± 0.6, p = .031), and VCAM-1 score (control 4.4 ± 0.4, saline 7.3 ± 1.0 vs. vardenafil 5.2 ± 0.4, p = .046) and increased cGMP score in the aortic wall (control 11.2 ± 0.8, saline 6.5 ± 0.8 vs. vardenafil 8.9 ± 0.6, p = .016). The marker for endothelial integrity (CD-31) was also higher in the vardenafil group (control 74 ± 4%, saline 22 ± 2% vs. vardenafil 40 ± 3%, p = .008). CONCLUSIONS: The results support the view that impairment of intracellular cGMP signalling plays a role in the pathogenesis of the endothelial dysfunction of an arterial graft after bypass surgery, which can effectively be prevented by vardenafil. Its clinical use as preconditioning drug could be a novel approach in vascular/cardiac surgery.

N-acetylcysteine protects against diabetic nephropathy through control of oxidative and nitrosative stress by recovery of nitric oxide in rats.

The diabetes mellitus (DM) induces several changes, with substantial increase of reactive oxygen species (ROS). The ROS cause damage to systemic and renal microvasculature, which could be one of the mechanisms involved in the development of diabetic nephropathy (DN). The ROS modulate other substances like the nitric oxide (NO), a vasodilator with important role in the renal function. N-acetylcysteine (NAC) is an antioxidant that acts replenishing intracellular cysteine levels, which is essential for glutathione formation. The aim of this study was to evaluate the effect of early or late NAC treatment on oxidative/nitrosative stress in DN progression. All rats were submitted to unilateral nephrectomy and diabetes was induced with streptozotocin. The animals were allocated into six groups: controls that received water (CTL) or NAC (CTL + NAC); diabetic groups that received early or late, water (DM-E; DM-L) or NAC (DM + NAC-E; DM + NAC-L), started on 5th day (early) or 4th week (late) after diabetes induction, during 8 weeks. After NAC treatment, the rats were placed in individual metabolic cages to obtain urine and blood samples for analysis of metabolic profile, renal function, thiobarbituric acid reactive substances (TBARS) and NO. At the end of the protocol, the renal cortex was removed for TBARS, NOS evaluation, antioxidants markers and histology. The DM-E group compared to CTL showed a significant increase in glycemia and proteinuria and impaired renal function; there was a significant increase of TBARS in plasma, urine and renal tissue, and also a significant decrease in plasma NO, which were reverted after early NAC treatment. The eNOS was decreased and iNOS was increased in DM-E vs. CTL, p < 0.05. The early NAC treatment in DM rats reduced proteinuria, creatinine, urea, TBARS and iNOS and, increased creatinine clearance, NO and eNOS, increasing significantly the antioxidant defenses, promoting elevated catalase and glutathione compared to DM-E group, all p < 0.05. The late NAC treatment in diabetic rats vs.DM-E showed reduced proteinuria and TBARS excretion and higher values of creatinine clearance and NO, all statistically significant. Histological analysis of the animals in DM-E or DM-L showed significant tubular changes with degeneration and vacuolization in tubular cells, dilated tubular lumen, intense glycosidic degeneration, and discreet mesangial expansion with interstitial fibrosis area. The DM + NAC-E group showed moderate glycosidic degeneration, however, did not present tubular degeneration or fibrosis. The DM + NAC-L group showed severe glycosidic degeneration, moderate tubular cell degeneration, light and focal dilatation of the tubules, with no fibrosis. Our study showed that NAC protected the diabetic rats against renal injury, probably due to the control of oxidative stress via recovery of the NO bioavailability, showing that early NAC was more effective than late treatment. All these data suggest that NAC may be useful in the adjuvant treatment in a safe way, in the early phase of the disease. Eventually, prolonged treatment, even if it is started later, could change the natural history of the disease, delaying the complications of diabetes in renal tissue.

Wogonin exacerbates the cytotoxic effect of oxaliplatin by inducing nitrosative stress and autophagy in human gastric cancer cells.

BACKGROUND: Gastric cancer remains one of the leading cause of death in the world. Drug combinations are potential approaches to provide more efficient treatments that minimize side effects. PURPOSE: We investigated the pharmacological effects of the combination of wogonin with oxaliplatin on gastric cancer cells in vitro and in vivo. METHODS AND RESULTS: In the present study, we found that wogonin enhanced the cytotoxicity of oxaliplatin; the drug combination resulted in strong synergistic inhibition of the cell viability in BGC-823 cells and in a zebrafish xenograft model. Interestingly, the combined treatment of wogonin and oxaliplatin modulated the expression of phospho-JNK (Thr183/Tyr185), phospho-ULK1 (Ser555) and the formation of LC3II. Confocal imaging data consistently showed that wogonin exacerbates the oxaliplatin-induced dissipation of the mitochondrial membrane potential (ΔΨm) and formation of peroxynitrite in BGC-823 cells. Moreover, wogonin allows a reduction in oxaliplatin dose when they are combined; therefore, it is a relevant strategy for reducing the side effects of oxaliplatin while achieving the same response. CONCLUSION: These results suggest that wogonin can be a potential therapeutic candidate for enhancing the efficacy of oxaliplatin in gastric cancer treatment.