Upregulation Of Nitric Oxide Synthase Research Articles

Coenzyme Q10 Activates the Antioxidant Machinery and Inhibits the Inflammatory and Apoptotic Cascades Against Lead Acetate-Induced Renal Injury in Rats.

The kidney is among the metabolic organs most susceptible to injury, particularly following exposure to xenobiotics and heavy metals. We aimed to explore the potential protective impacts of coenzyme Q10 (CoQ10) on lead acetate (PbAc)-induced nephrotoxicity in rats. Four experimental groups (n = 7) were applied as follows: control group, CoQ10 alone (10 mg/kg), PbAc alone (20 mg/kg), and PbAc with CoQ10. Exposure to PbAc led to the accumulation of Pb in the kidney and increased urea and creatinine serum levels. The deposition of Pb coupled with the elevation of malondialdehyde and nitrate/nitrite levels along with the upregulation of inducible nitric oxide synthase. Additionally, upon PbAc poisoning, glutathione content and the antioxidant enzymes were depleted along with the downregulation of Nrf2 and HO-1 expression. Moreover, PbAc injection increased the protein and mRNA levels of pro-inflammatory cytokines namely, tumor necrosis factor-alpha and interleukin-1 beta, while decreased the levels of interleukin-10, an anti-inflammatory cytokine, in the kidney. Furthermore, exposure to PbAc correlated with increased levels of pro-apoptotic markers, Bax and caspase-3, and reduced levels of the anti-apoptotic marker Bcl-2. The administration of CoQ10 alleviated the molecular, biochemical and histological changes following PbAc intoxication. Thus, CoQ10 reduces the deleterious cellular side effects of PbAc exposure due to its antioxidant, anti-inflammatory and anti-apoptotic effects.

Perinatal taurine exerts a hypotensive effect in male spontaneously hypertensive rats and down‐regulates endothelial oxide nitric synthase in the aortic arch

Essential hypertension is considered to be a result of the interaction between genetic and environmental factors, including perinatal factors. Different advantageous perinatal factors proved to have beneficial long-lasting effects against an abnormal genetic background. Taurine is a ubiquitous sulphur-containing amino acid present in foods such as seafood. The antihypertensive effects of taurine have been reported in experimental studies and in human hypertension. We aimed to investigate the effects of perinatal treatment with taurine in spontaneously hypertensive rats (SHR), a known model of genetic hypertension. Female SHR were administered with taurine (3g/L) during gestation and lactation (SHR-TAU). Untreated SHR and Wistar-Kyoto rats (WKY) were used as controls. Long-lasting effects in offspring were investigated. Addition of taurine to the mother's drinking water reduced blood pressure in adult offspring. No differences were observed in cardiac hypertrophy. Findings on morphometric evaluations suggest that perinatal treatment with taurine would be partially effective in improving structural alterations of the aorta. Modifications in gene expression of Bcl-2 family members and upregulation of endothelial nitric oxide synthase in the aorta of 22-week-old male offspring were found. No differences were observed on relative telomere length in different cardiovascular tissues between SHR and SHR-TAU. Altogether results suggest that taurine programming, albeit sex specific, is associated with gene expression changes which ultimately may lead to improvement of aortic remodelling and enhanced endothelial function because of augmented nitric oxide (NO) production.

Effect of heat-killed Enterococcus faecalis EF-2001 on ethanol-induced acute gastric injury in mice: Protective effect of EF-2001 on acute gastric ulcer.

Enterococcus faecalis is a facultative anaerobic gram-positive commensal bacterium common in the gastrointestinal tract of animals and humans. This study aimed to investigate the protective effects of heat-killed E. faecalis EF-2001 (EF-2001) on acute gastric ulcer using a murine model of ethanol (EtOH)-induced acute gastric injury. EF-2001 (20, 40, and 80 mg/kg/day) was administered by oral gavage for 5 days before EtOH treatment (10 mL/kg body weight). EF-2001 effectively attenuated EtOH-induced gastric mucosal injury with reduced gastric mucosal ulcer and histological damage score. Pretreatment of EF-2001 markedly suppressed the phosphorylation of mitogen-activated protein kinases (MAPKs; ERK1/2, JNK, and p38MAPK). In addition, EF-2001 significantly inhibited phosphorylation of nuclear factor kappa B (NF-κB) and subsequently suppressed the upregulation of inducible nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6 in gastric tissues. Taken together, these results suggest that EF-2001 exerts a gastroprotective effect against acute gastric injury, and the underlying mechanism might be associated with the suppression of MAPKs and NF-κB signaling and consequent reduction of pro-inflammatory mediators or cytokines.

Role of Macrophages in Status Epilepticus Predisposing to Alzheimer’s Disease

Continuous epileptic seizures hallmark status epilepticus, leading to preferential neuronal cell loss in the hippocampus that can progress into Alzheimer's disease. Previous studies have shown that status epilepticus prompts an overproduction of nitric oxide (NO) by upregulation of NO synthase II (NOS II) to induce apoptosis of neuronal cells in the hippocampus, in a nuclear factor-kappaB (NF-κB) signaling dependent manner. Here, in an experimental rat model for status epilepticus, elicitation of sustained seizure activity was achieved by microinjection of kainic acid (KA) into the hippocampal CA3 subfield. We found that KA induced features of status epilepticus, which could be attenuated by blocking NF-κB signaling through a specific inhibitor. Interestingly, infiltration of macrophages of primarily pro-inflammatory subtype was detected in the hippocampal CA3 region immediately after KA injection. Experimental elimination of macrophages by an anti-CD115 antibody significantly attenuated the features of status epilepticus, likely through suppressing activation of NF-κB signaling. Together, these data suggest that macrophages play a critical role in NF-κB signaling-mediated status epilepticus that predisposes to Alzheimer's disease.

Nitric oxide produced by periostial hemocytes modulates the bacterial infection-induced reduction of the mosquito heart rate.

The circulatory and immune systems of mosquitoes are functionally integrated. An infection induces the migration of hemocytes to the dorsal vessel, and specifically, to the regions surrounding the ostia of the heart. These periostial hemocytes phagocytose pathogens in the areas of the hemocoel that experience the highest hemolymph flow. Here, we investigated whether a bacterial infection affects cardiac rhythmicity in the African malaria mosquito, Anopheles gambiae We discovered that infection with Escherichia coli, Staphylococcus aureus and Staphylococcus epidermidis, but not Micrococcus luteus, reduces the mosquito heart rate and alters the proportional directionality of heart contractions. Infection does not alter the expression of genes encoding crustacean cardioactive peptide (CCAP), FMRFamide, corazonin, neuropeptide F or short neuropeptide F, indicating that they do not drive the cardiac phenotype. Infection upregulates the transcription of two superoxide dismutase (SOD) genes, catalase and a glutathione peroxidase, but dramatically induces upregulation of nitric oxide synthase (NOS) in both the heart and hemocytes. Within the heart, nitric oxide synthase is produced by periostial hemocytes, and chemically inhibiting the production of nitric oxide using l-NAME reverses the infection-induced cardiac phenotype. Finally, infection induces the upregulation of two lysozyme genes in the heart and other tissues, and treating mosquitoes with lysozyme reduces the heart rate in a manner reminiscent of the infection phenotype. These data demonstrate an exciting new facet of the integration between the immune and circulatory systems of insects, whereby a hemocyte-produced factor with immune activity, namely nitric oxide, modulates heart physiology.

Erectile dysfunction and statins: The assorted view of preponderance

Objective: To explore the association between statin therapy and the risk of erectile dysfunction by literature review.Methods: We conducted diversities of search strategies including electronic database searches of MEDLINE, Scopus, Pubmed and Web of Science using MeSH terms, keywords and title words during the search. Reference lists of identified and public articles were reviewed. In addition, only English articles were considered and case reports were not concerned in the review. The key features of recognized applicable search studies were considered and the conclusions were summarized in a narrative review.Results: Different studies gave a consensus that erectile dysfunction was regarded as an early sign of silent cardiovascular disorder and hidden atherosclerosis. Different studies reported that statins might induce erectile dysfunction through induction of peripheral neuropathy, cognitive deficits, and reduction of circulating testosterone. However, most of recent studies illustrated that statins led to a significant improvement in erectile function and sexual health in men with age over forty years. Atorvastatin advanced endothelial nitric oxide concentrations through activation and upregulation of endothelial nitric oxide synthase and rescued phosphodiesterase-5 inhibitors non-responders since nitric oxide and cyclic guanosine monophosphate increased penile blood flow and improved erectile function.Conclusions: According to the assorted view of preponderance, statins improved erectile dysfunction is more dominant than statins induced erectile dysfunction. Therefore, statins regardless of its property improve erectile dysfunction through amelioration of penile endothelial dysfunction, and penile neuronal reflexes that are inter-related during sexual excitation and penile erection.

Nephroprotective Role of Beta vulgaris L. Root Extract against Chlorpyrifos-Induced Renal Injury in Rats.

Organophosphorus pesticides (OPs) are widely used for agricultural and housekeeping purposes. Exposure to OPs is associated with the progression of several health issues. Antioxidant agents may be powerful candidates to minimise adverse reactions caused by OPs. The aim of the present study was to evaluate the nephroprotective effects of red beetroot extract (RBR) against chlorpyrifos- (CPF-) induced renal impairments. CPF induced kidney dysfunction, as demonstrated by changes in serum creatinine and urea levels. Moreover, CPF exposure induced oxidative stress in the kidneys as determined by increased malondialdehyde and nitric oxide levels, decreased glutathione content, decreased catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase activities, and decreased nuclear factor (erythroid-derived 2)-like-2 factor expression. In addition, CPF induced inflammation in renal tissue as evidenced by increased release of tumor necrosis factor-alpha and interleukin-1β and upregulation of inducible nitric oxide synthase. Furthermore, CPF promoted cell death as demonstrated by decreased Bcl-2 and increased Bax and caspase-3 levels. Treatment with RBR one hour prior to CPF treatment blocked the effects observed in response to CPF alone. Our results suggest that RBR could be used to alleviate CPF-induced nephrotoxicity through antioxidant, anti-inflammatory, and antiapoptotic activities.

High-Fat Diet Enriched with Bilberry Modifies Colonic Mucus Dynamics and Restores Marked Alterations of Gut Microbiome in Rats.

Emerging evidence suggests that high-fat diet (HFD) is associated with gut microbiome dysbiosis and related disorders. Bilberry is a prebiotic food component with known health benefits. Herein, the dynamics of the colonic mucus layer and microbiome during HFD and bilberry supplementation are addressed. The effects on colonic mucus thickness in vivo and gut microbiota composition (Illumina sequencing, quantitative real-time PCR) are investigated in young rats fed a low-fat diet or HFD with or without bilberries for 8 weeks (n = 8). HFD induced significant local colonic effects, despite no observed weight gain or systemic inflammation, as HFD causes epithelial upregulation of inducible nitric oxide synthase, which is counteracted by bilberry. The firmly adherent mucus layer becomes thicker and the mRNA levels of Muc2 and Tff3 are increased by HFD with or without bilberry. In parallel, HFD reduced the colonic abundance of mucolytic bacterial species Akkermansia muciniphila and Bacteroides spp. Finally, bilberry prevents HFD-induced microbiota dysbiosis, including expansion of pathobionts, for example, Enterobacteriaceae. HFD expand firmly adherent mucus thickness and reduce mucus-foraging bacteria populations in the colon prior to obesity. Enriching HFD with bilberry protects against intestinal inflammation and marked microbiota encroachment.

Cellular and physiological upregulation of inducible nitric oxide synthase, arginase, and inducible cyclooxygenase in wound healing.

Wound repair is regulated by overlapping cellular, physiological and biochemical events. Prostaglandins and nitric oxide have been a focus for inflammation research particularly since the discovery of their inducible isoforms nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Study of the cellular expression of iNOS and COX-2 and arginase which competes with iNOS for its substrate, in an in vivo model of wound healing could reveal important roles for these enzymes in the physiological progression of wound repair. Adult male rats received full thickness dermal wounds which were harvested at different times. Protein levels and activities of the enzymes were assessed by western blot and biochemical assays respectively. The cellular distribution and the colocalization were assessed by immunostaining. The protein levels and activities of iNOS, arginase, and COX-2 increased only during the inflammatory phase of wound. Immunocytochemistry showed that the three enzymes were coexpressed and the main cellular source was inflammatory cells mainly macrophages. iNOS was induced at the wound site and was the earliest to increase significantly (p < 0.05) for only up to 3 days postwounding. However, arginase and COX-2 significant ( p < 0.05) upregulation started at a later time points and continued for up to 14 days postwounding. Therefore iNOS, compared with arginase and COX-2, showed a temporal difference in expression during wound healing which could be explained by their products being required at different stages of the healing process. The coordinated expression of the three enzymes at different time points could account for the physiological progression of the healing process.

Caloric restriction induces H2O2 formation as a trigger of AMPK-eNOS-NO pathway in obese rats: Role for CAMKII

Caloric restriction (CR) improves endothelial function through the upregulation of adenosine monophosphate-activated protein kinase (AMPK) and endothelial nitric oxide synthase (eNOS). Moreover, hydrogen peroxide (H2O2) is upregulated in yeast subjected to CR. Our aim was to assess if mild short-term CR increases vascular H2O2 formation as a link with AMPK and eNOS activation.Twelve-week old Zucker obese (fa/fa) and control Zucker lean male rats were fed a standard chow either ad libitum (AL, n=10) or with a 20% CR (CR, n=10) for two weeks. CR significantly improved relaxation to ACh in fa/fa rats because of an enhanced endogenous production of H2O2 in aortic rings (H2O2 levels fa/faAL=0.5 ± 0.05 nmol/mg vs. H2O2 levels fa/faCR=0.76 ± 0.07 nmol/mg protein; p<0.05). Expression of mitochondrial superoxide dismutase (Mn-SOD) and total SOD activity were increased in aorta from fa/fa animals after CR. In cultured aortic endothelial cells, serum deprivation or 2-deoxy-d-glucose induced a significant increase in: i) superoxide anion and H2O2 levels, ii) p-AMPK/AMPK and p-eNOS/eNOS expression and iii) nitric oxide levels. This effect was reduced by catalase and strongly inhibited by Ca2+/calmodulin-dependent kinase II (CamkII) silencing.In conclusion, we propose that mild short-term CR might be a trigger of mechanisms aimed at protecting the vascular wall by the increase of H2O2, which then activates AMPK and nitric oxide release, thus improving endothelium-dependent relaxation. In addition, we demonstrate that CAMKII plays a key role in mediating CR-induced AMPK activation through H2O2 increase.

Morphological and neurochemical plasticity of rat mesencephalic trigeminal neurons

The mesencephalic trigeminal nucleus (Me5) is a unique structure in the central nervous system (CNS), made up of pseudounipolar sensory neurons. It is also a suitable paradigm for studying the plastic alterations in neurons. It is known that the Me5 neurons utilize various neurotransmitters under normal conditions, though little information is available about the morphological and chemical events taking place in the nucleus after injury. This review provides concise description of the structural adaptive changes in Me5 neurons following peripheral axotomy of the masseteric nerve. Furthermore, it validates NADPH-diaphorase activity in them, and using immunohistochemistry for glutamate (Glu), substance P (SP), calcitonin-gene related protein (CGRP), neuropeptide tyrosine (NPY) and galanin (GAL), it deals with the altered neurochemical phenotype of the injured neurons. Our results distinctly show that the Me5 neurons in the rat are extremely sensitive to peripheral injury and we demonstrate their distinct structural and neurochemical plasticity. The adaptive morphological alterations comprise of both qualitative and quantitative alterations in the axotomized Me5 population which are statistically significant when compared with the number and phenotype of the neurons on the contralateral intact side. Besides, the axotomy-induced alterations in the neurochemical character of Me5 are best signified by the down-regulation of the classical neurotransmitters under normal conditions, and the up-regulation of nitric oxide synthase and de novo synthesis of certain neuroactive substances such as NPY, SP, GAL and VIP. It can be inferred that the described phenomena only occur in the nucleus in cases of injury and changes in the environmental cues, and serve as adaptive mechanisms and powerful trophic factors for the neuronal survival in the Me5. There is, undoubtedly, still a long way to go in order to clarify the dynamic and plastic alterations occurring in the CNS in health and disease, and also explain their role in such important functions as pain, perception, learning, cognition and memory.

Anti-inflammatory effects of xanthohumol in RAW 264.7 macrophages are mediated through the activation of AMP kinase

Abstract Xanthohumol (XN), a prenylated chalcone extracted from common hop plants, has been studied for its anti-inflammatory properties. In this study, we hypothesize that XN induces M2 polarization of macrophages and the resulting anti-inflammatory effects are mediated through the activation of adenosine monophosphate-activated protein kinase (AMPK) signaling pathway. RAW 264.7 cells were treated with either 0.1% DMSO or XN and the culture supernatant was collected for ELISA and whole cell lysates were collected for western blotting. Our results demonstrate that XN upregulated the secretion of IL10, a signature cytokine for M2 polarization, in RAW264.7 cells. We further demonstrated that XN increased arginase expression, a marker for M2 polarization, and suppressed IFNγ-mediated upregulation of inducible nitric oxide synthase (iNOS) expression, a marker for M1 polarization. Additionally, XN decreased IFNγ – induced elevation of nitrite release, indicating the inhibitory effects of XN against M1 polarization. Furthermore, XN at 25μM increased the secretion of catecholamines from macrophages comparable to IL4, an inducer of M2 phenotype and these effects were accompanied by an increased expression of tyrosine hydroxylase, a rate-limiting enzyme of catecholamine biosynthesis. Finally, XN and AICAR, an AMPK stimulator, upregulated the expression of phospho-AMPK and arginase while dorsomorphin, an established inhibitor of the AMPK pathway failed to do so in RAW264.7 cells. These results provide evidence for the anti-inflammatory effects of XN mediated through the induction of M2 polarization and activation of AMPK signaling pathway.

Human Atrial Natriuretic Peptide in Cold Storage of Donation After Circulatory Death Rat Livers: An Old but New Agent for Protecting Vascular Endothelia?

Current critical shortage of donor organs has increased the use of donation after circulatory death (DCD) livers for transplantation, despite higher risk for primary nonfunction or ischemic cholangiopathy. Human atrial natriuretic peptide (hANP) is a cardiovascular hormone that possesses protective action to vascular endothelia. We aimed to clarify the therapeutic potential of hANP in cold storage of DCD livers. Male Wistar rats were exposed to 30-minute warm ischemia in situ. Livers were then retrieved and cold-preserved for 6 hours with or without hANP supplementation. Functional and morphological integrity of the livers was evaluated by oxygenated ex vivo reperfusion at 37°C. hANP supplementation resulted in significant reduction of portal venous pressure (12.2 ± 0.5 versus 22.5 ± 3.5 mm Hg, P < 0.001). As underlying mechanisms, hANP supplementation significantly increased tissue adenosine concentration (P = 0.008), resulting in significant upregulation of endothelial nitric oxide synthase and significant downregulation of endothelin-1 (P = 0.01 and P = 0.004 vs. the controls, respectively). Consequently, hANP significantly decreased transaminase release (P < 0.001) and increased bile production (96.2 ± 18.2 versus 36.2 ± 15.2 μL/g-liver/h, P < 0.001). Morphologically, hepatocytes and sinusoidal endothelia were both better maintained by hANP (P = 0.021). Electron microscopy also revealed that sinusoidal ultrastructures and microvilli formation in bile canaliculi were both better preserved by hANP supplementation. Silver staining also demonstrated that hANP significantly preserved reticulin fibers in Disse space (P = 0.017), representing significant protection of sinusoidal frameworks/architectures. Supplementation of hANP during cold storage significantly attenuated cold ischemia/warm reperfusion injury of DCD livers.

Priming of microglia with IFN-γ slows neuronal gamma oscillations in situ

Type II IFN (IFN-γ) is a proinflammatory T lymphocyte cytokine that serves in priming of microglia-resident CNS macrophages-during the complex microglial activation process under pathological conditions. Priming generally permits an exaggerated microglial response to a secondary inflammatory stimulus. The impact of primed microglia on physiological neuronal function in intact cortical tissue (in situ) is widely unknown, however. We explored the effects of chronic IFN-γ exposure on microglia in hippocampal slice cultures, i.e., postnatal parenchyma lacking leukocyte infiltration (adaptive immunity). We focused on fast neuronal network waves in the gamma-band (30-70 Hz). Such gamma oscillations are fundamental to higher brain functions, such as perception, attention, and memory, and are exquisitely sensitive to metabolic and oxidative stress. IFN-γ induced substantial morphological changes and cell population expansion in microglia as well as moderate up-regulation of activation markers, MHC-II, CD86, IL-6, and inducible nitric oxide synthase (iNOS), but not TNF-α. Cytoarchitecture and morphology of pyramidal neurons and parvalbumin-positive inhibitory interneurons were well-preserved. Notably, gamma oscillations showed a specific decline in frequency of up to 8 Hz, which was not mimicked by IFN-α or IL-17 exposure. The rhythm disturbance was caused by moderate microglial nitric oxide (NO) release demonstrated by pharmacological microglia depletion and iNOS inhibition. In conclusion, IFN-γ priming induces substantial proliferation and moderate activation of microglia that is capable of slowing neural information processing. This mechanism might contribute to cognitive impairment in chronic brain disease featuring elevated IFN-γ levels, blood-brain barrier leakage, and/or T cell infiltration, well before neurodegeneration occurs.

Activation of G protein-coupled estrogen receptor protects intestine from ischemia/reperfusion injury in mice by protecting the crypt cell proliferation.

The intestinal ischemia/reperfusion (I/R) injury is a common clinical event related with high mortality in patients undergoing surgery or trauma. Estrogen exerts salutary effect on intestinal I/R injury, but the receptor type is not totally understood. We aimed to identify whether the G protein-coupled estrogen receptor (GPER) could protect the intestine against I/R injury and explored the mechanism. Adult male C57BL/6 mice were subjected to intestinal I/R injury by clamping (45 min) of the superior mesenteric artery followed by 4 h of intestinal reperfusion. Our results revealed that the selective GPER blocker abolished the protective effect of estrogen on intestinal I/R injury. Selective GPER agonist G-1 significantly alleviated I/R-induced intestinal mucosal damage, neutrophil infiltration, up-regulation of TNF-α and cyclooxygenase-2 (Cox-2) expression, and restored impaired intestinal barrier function. G-1 could ameliorate the impaired crypt cell proliferation ability induced by I/R and restore the decrease in villus height and crypt depth. The up-regulation of inducible nitric oxide synthase (iNOS) expression after I/R treatment was attenuated by G-1 administration. Moreover, selective iNOS inhibitor had a similar effect with G-1 on promoting the proliferation of crypt cells in the intestinal I/R model. Both GPER and iNOS were expressed in leucine-rich repeat containing G-protein coupled receptor 5 (Lgr5) positive stem cells in crypt. Together, these findings demonstrate that GPER activation can prompt epithelial cell repair following intestinal injury, which occurred at least in part by inhibiting the iNOS expression in intestinal stem cells (ISCs). GPER may be a novel therapeutic target for intestinal I/R injury.

Stimulation of bovine monocyte-derived macrophages with lipopolysaccharide, interferon-\u0263, Interleukin-4 or Interleukin-13 does not induce detectable changes in nitric oxide or arginase activity

BackgroundBacterial lipopolysaccharide and interferon-γ stimulation of rodent macrophages in vitro induces up-regulation of inducible nitric oxide synthase, whereas interleukin-4 stimulation results in increased activity of arginase-1. Thus different stimulants result in differing macrophage phenotypes, appropriate for responses to a range of pathogens. The current study was conducted in order to determine whether bovine macrophages derived from monocytes and spleen respond similarly.ResultsLipopolysaccharide and interferon-γ did not induce detectable increases in nitric oxide production by bovine monocyte-derived or splenic macrophages in vitro. Similarly, interleukin-4 and interleukin-13 did not affect arginase activity. However, changes in transcription of genes coding for these products were detected.ConclusionDifferences between macrophage activation patterns exist between cattle and other species and these differences may occur during the post-transcription phase.

Neuroprotective effects of a potent bradykinin B2 receptor antagonist HOE-140 on microvascular permeability, blood flow disturbances, edema formation, cell injury and nitric oxide synthase upregulation following trauma to the spinal cord.

Bradykinin is a mediator of vasogenic brain edema formation. Recent reports suggest that bradykinin interacts with nitric oxide synthase (NOS) system in the central nervous system (CNS). However, role of bradykinin in spinal cord injury (SCI) induced alterations in the blood-spinal cord barrier (BSCB), spinal cord blood flow (SCBF), edema formation and cell changes are still not well known. Our previous reports showed that SCI induces marked upregulation of neuronal NOS (nNOS) in the cord associated with BSCB disruption, edema formation and cell injury. Thus, a possibility exists that bradykinin participates in SCI induced nNOS upregulation and cord pathology. To explore this idea a potent bradykinin B2 receptor antagonist HOE-140 was used in our rat model of SCI and cord pathology. SCI was inflicted in Equithesin anesthetized rats by making a longitudinal incision (2mm deep and 5mm long) into the right dorsal horn of the T10-11 segment. The animals were allowed to survive 5h after injury. A focal SCI significantly disrupted BSCB to Evans blue and [131]I-sodium in the traumatized and adjacent segments. Interestingly, far remote spinal cord segments C4 and T5 segments also affected within 5h. These spinal cord segments also exhibited pronounced reductions in the SCBF (mean-30%), increased edematous swelling and profound neuronal damages. Upregulation of nNOS expression is seen in both the dorsal and ventral horns of the spinal cord exhibiting cord pathology. At the ultrastructural level, exudation of lanthanum is seen within the endothelial cell cytoplasm and occasionally in the basal lamina. Pretreatment with low doses of HOE-140 (0. 1mg to 1mg/kg, i.v.) 30min prior to SCI significantly enhanced the SCBF and reduced the BSCB disruption, edema formation, nNOS upregulation and cell injury. However, HOE-140 in doses ranging from 2mg to 5mg/kg, i.v. did not induce significant neuroprotection. These observations are the first to suggest that bradykinin B2 receptors play an important role in BSCB permeability, SCBF, edema formation, nNOS upregulation and cell injury following acute SCI, not reported earlier.

Exacerbation of blood-brain barrier breakdown, edema formation, nitric oxide synthase upregulation and brain pathology after heat stroke in diabetic and hypertensive rats. Potential neuroprotection with cerebrolysin treatment.

There is a growing trend of hypertension among military and civilian populations due to lifetime stressful situations. If hypertension is uncontrolled it leads to development of diabetes and serious neurological complications. Most of the World populations live in temperate zone across the World. Thus, a possibility exists that these hypertensive and diabetic people may have external heat as potential risk factors for brain damage. We have seen brain edema and brain damage following exposure to heat stress at 38°C for 4h. A possibility exists that heat exposure in diabetic-hypertensive (DBHY) cases exacerbates exacerbation of brain pathology and edema formation. This hypothesis is examined in a rat model. The role of nitric oxide (NO) in exacerbation of HS-induced brain pathology was also evaluated using nitric oxide synthase (NOS) immunoreactivity. Hypertensive rats (produced by two-kidney one clip (2K1C) method) were made diabetic with streptozotocine (50mg/kg, i.p./day for 3days) treatment. After 6weeks, DBHY rats show 20-30mM/L Blood Glucose and hypertension (180-200mmHg). Subjection of these rats to 4h HS resulted in six- to eightfold higher BBB breakdown, brain edema formation and brain pathology. At this time, neuronal or inducible NOS expression was four- to sixfold higher in DBHY rats compared to controls. Interestingly, iNOS expression was higher than nNOS in DBHY rats. Cerebrolysin in high doses (10-mL/kg, i.v. instead of 5-mL/kg) induced significant neuroprotection and downregulation of nNOS and iNOS in DBHY animals whereas normal animals need only 5-mL/kg doses for this purpose. Our observations demonstrate that co-morbidly factors exacerbate brain damage in HS through NOS expression and require double dose of cerebrolysin for neuroprotection as compared to normal rats, not reported earlier.

The Anti-Inflammatory Effect of Sulforaphane in Mice with Experimental Autoimmune Encephalomyelitis.

BackgroundMultiple sclerosis (MS) is an immune-associated inflammatory disorder of the central nervous system and results in serious disability. Although many disease-modifying therapy drugs have been developed, these drugs have shown limited clinical efficacy and some adverse effects in previous studies, therefore, there has been reasonable need for less harmful and cost-effective therapeutics. Herein, we tested the anti-inflammatory effect of sulforaphane (SFN) in a mouse model of experimental autoimmune encephalomyelitis (EAE).MethodsThe EAE mice were randomly assigned into two experimental groups: the phosphate-buffered saline (PBS)-treated EAE group and SFN-treated EAE group. After EAE mice induction by auto-immunization against the myelin oligodendrocyte glycoprotein peptide, we evaluated EAE symptom scores and biochemical analyses such as infiltration of inflammatory cells and demyelination of the spinal cord. Furthermore, western blotting was performed using the spinal cords of EAE mice.ResultsIn the behavioral study, the SFN-treated EAE mice showed favorable clinical scores compared with PBS-treated EAE mice at the 13th day (1.30 ± 0.15 vs. 1.90 ± 0.18; P = 0.043) and 14th day (1.80 ± 0.13 vs. 2.75 ± 0.17; P = 0.003). Additionally, the biochemical studies revealed that SFN treatment inhibited the inflammatory infiltration, demyelinating injury of the spinal cords, and the up-regulation of inducible nitric oxide synthase in the EAE mice.ConclusionThe SFN treatment showed anti-inflammatory and anti-oxidative effects in the EAE mice. Conclusively, this study suggests that SFN has neuroprotective effects via anti-inflammatory processing, so it could be a new therapeutic or nutritional supplement for MS.

Loganin prevents BV-2 microglia cells from Aβ1-42 -induced inflammation via regulating TLR4/TRAF6/NF-κB axis.

Neuroinflammation is closely related with the pathogenesis and progress of neurodegenerative diseases including Alzheimer's disease (AD). Loganin, an iridoid glycoside obtained from traditional Chinese medicine Cornus officinalis, has properties of inhibiting inflammation and improving memory. The present study was aimed to investigate effects of loganin on Aβ-induced inflammation and to explore the underlying mechanisms. BV-2 microglia cells were stimulated with 10 µM Aβ1-42 for 24 h to induce inflammatory damage. According to results of CCK-8 assay, the doses of loganin in present work were 10 and 30 µM. We found that treatment with loganin could inhibit Aβ1-42 -induced microglia activation. Furthermore, loganin treatment prevented the over-production of Tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), Macrophage Chemotactic Protein 1(MCP-1), Nitric oxide (NO), Prostaglandin E2 (PGE2) and the up-regulation of inducible nitric oxide synthase (iNOS) and Cyclooxygenase 2 (COX-2) in Aβ1-42 -stimulated BV-2 cells. Results from Western blots demonstrated that loganin inhibited Aβ1-42 -induced elevation in Toll-like receptor 4 (TLR4), Myeloid Differentiation Factor 88 (MyD88) and TNF receptor-associated factor 6 (TRAF6). Loganin treatment also attenuated the increased phosphorylation level of IRAK4 caused by Aβ1-42 . Additionally, loganin alleviated nuclear translocation of NF-κB p65 subunit in Aβ1-42 -stimulated BV-2 cells, and this phenomenon could be reversed by TLR4 agonist LPS. Further, the anti-inflammatory effects of loganin were attenuated when TLR4 signaling pathway was re-activated by LPS. Taken together, our data indicated that loganin could attenuate inflammatory response induced by Aβ in BV-2 microglia cells, partially through deactivating the TLR4/TRAF6/NF-κB axis.