Nitrite Oxide Levels Research Articles

Resveratrol attenuates malathion-induced renal damage by declining oxidative stress in rats

Background: Malathion is the most organophosphates which are capable to produce free radicals and induce disturbance in body antioxidant. Resveratrol is an herbal polyphenol and it has been beneficial antioxidant effects during short‑term administration. This study was designed to evaluate the effects of resveratrol against damage induced by malathion to the kidneys of rats. Materials and Methods: Forty‑eight Wistar rats divided randomly into eight groups (n = 6): sham (saline) and malathion control treated groups (27 mg/kg); resveratrol groups (2, 8, and 20 mg/kg); and resveratrol + malathion‑treated groups (2, 8, and 20 mg/kg). Treatments were administered intraperitoneally and gavage daily for 45 days. Parameters related to the function and the histology of the kidneys were evaluated and statistically analyzed from kidney and blood serum samples in respect of the groups. Results: Malathion administration increased significantly Bowman’s space, qualitative histopathology indices, kidney malondialdehyde (MDA) level, blood urea nitrogen (BUN), creatinine, and nitrite oxide levels and decreased significantly total antioxidant capacity (TAC) level and diameter and number of renal corpuscles compared to the Sham group (P < 0.001). The resveratrol and resveratrol + malathion treatments in a dose‑dependent manner reduced significantly Bowman’s space, qualitative histopathology indices, kidney MDA level, BUN, creatinine, and nitrite oxide levels and increased significantly TAC level and diameter and number of renal corpuscles compared to the malathion control group (P < 0.001). Conclusion: It seems that resveratrol administration in a dose‑dependent manner improved kidney injury induced by malathion in rats.

THE EFFECT OF RECOMBINANT VASCULAR ENDOTHELIAL GROWTH FACTOR 121 ON NITRIDE OXIDE LEVEL IN MICE (Mus musculus) MODEL OF PREECLAMPSIA

Preeclampsia is a multifactorial syndrome in pregnancy whose cause is still unknown. Several proangiogenic and antiangiogenic mediators such as Vascular Endothelial Growth Factor (VEGF) and Nitrite Oxide (NO) play important roles in preventing preeclampsia. VEGF can increase NO level that lowers maternal blood pressure, improves endothelial function and reduces placental hypoxia in preeclampsia. Recombinant VEGF 121 is expected to be an option in the prevention and treatment of preeclampsia. This experimental study used mice (Mus musculus) as the model. The objective of this study was to observe the effect of recombinant VEGF 121 in increasing the level of nitric oxide in mice (Mus musculus) model of preeclampsia. This was an experimental analytical study with Randomized Control Trial (RCT) design. The study enrolled 27 pregnant mice (Mus musculus) which met the restriction criteria divided into 3 groups. The first group (K1) were 9 normal pregnant mice. The second group (K2) were 9 pregnant mice of preeclampsia model without treatment. The third group (K3) were 9 pregnant mice of preeclampsia model receiving recombinant VEGF 121 therapy. The independent variable was the administration of recombinant VEGF 121 and the dependent variable was the serum NO level. Statistical analysis was performed by using anova statistics. NO level in the first group (K1) was 1.746±0.347, with minimum value of 1.00 µM, and maximum value of 2.28 µM, CI (1.479-2.013). NO level in second group (K2) was 1.167±0.380, with minimum value of 0.64 µM, and maximum value of 1.94 µM, CI (0.875-1.460). NO level in the third group (K3) was 2.164±0.556, with minimum value of 1.56 µM, and maximum value of 5.96 µM, CI (1.842-2.486). With anova statistical test, there were significant differences between K1 group and K2 group (p value=0.004&lt;0.05), K1 group and K3 group (p value=0.000&lt;0.05) as well as K2 group and K3 group (p value=0.029&lt;0.05). In conclusion, Recombinant VEGF 121 increased the level of nitric oxide in mice (Mus musculus) model of preeclampsia significantly.

The immunomodulatory effect of Zingiber cassumunar ethanolic extract on phagocytic activity, nitrit oxide and reaxtive oxygen intermediate secretions of macrophage in mice

Immunomodulators could protect the body from a variety of infectious agents and boost immunity. Zingiber cassumunar rhizome or bangle potentially showed as an immunomodulator through increasing of macrophage activity in vitro. The objective of the study was to determine the effect of Z. cassumunar rhizome ethanolic extract on phagocytic activity, nitrite oxide (NO) and reactive oxygen intermediate (ROI) secretions in macrophages in vivo. A total of 200 g of Z. cassumunar rhizome was powdered, macerated in 96% ethanol and evaporated to get concentrated extract. Mice were divided into 5 groups as follow: the normal group was given by water only, the negative control group was given by a 0.94% CMC-Na suspension, the treatment groups were given by 250, 500 and 1000 mg/kgBW, respectively, of Z. cassumunar ethanolic extract. The extract was administered orally for 7 days. On the 8th day the mice were injected intraperitoneally 0.7 mg/kg BW of lipopolysaccharide. Four hours later macrophage was isolated. Furthermore, the determination of the phagocytic activity, NO and ROI secretions levels of macrophage were performed. The treatments of 250, 500 and 1000 mg/kg BW of Z. cassumunar ethanolic extract significantly increase the ROI and NO secretions levels (p<0.05), but did not increase the phagocytic activity (p>0.05) of macrophage. Z. cassumunar ethanolic extract have immunomodulatory effect in vivo.

Protodioscin ameliorates oxidative stress, inflammation and histology outcome in Complete Freund's adjuvant induced arthritis rats.

Protective effect of protodioscin or methyl protodioscin against inflammation had been reported in various inflammation diseases. This study aimed to investigate the effect of protodioscin against Complete Freund's adjuvant (CFA)-induced arthritis rats. Rats randomly divided into model groups were injected with CFA, companied with different dose of protodioscin (50, 100, and 200mg/kg body weight). The histology, changes in biochemical parameters and inflammatory cytokines expression were detected for anti-inflammation effect evaluation of protodioscin. CFA treatment induced arthritic rats with swelling paw, ankle inflammation, and area of lymphocyte infiltration, upregulated inflammatory cytokines (IL-1β, TNF-α, cyclo-oxygenase 2, and IL-6 as well as prostaglandin E2), articular elastase, myeloperoxidase, lipid peroxidase and nitrite oxide levels, downregulated glutathione, catalase, and superoxide dismutase. In contrast, protodioscin ameliorated all the changes induced by CFA in rats, suggesting the anti-inflammatory effect of protodioscin. We concluded that protodioscin administration into CFA-induced arthritis rats protected against CFA-induced oxidative stress, neutrophil infiltration, and inflammation, suggesting the anti-inflammatory effect and the therapeutic potential of protodioscin for arthritis.

Migraines Are Correlated with Higher Levels of Nitrate-, Nitrite-, and Nitric Oxide-Reducing Oral Microbes in the American Gut Project Cohort.

Nitrates, such as cardiac therapeutics and food additives, are common headache triggers, with nitric oxide playing an important role. Facultative anaerobic bacteria in the oral cavity may contribute migraine-triggering levels of nitric oxide through the salivary nitrate-nitrite-nitric oxide pathway. Using high-throughput sequencing technologies, we detected observable and significantly higher abundances of nitrate, nitrite, and nitric oxide reductase genes in migraineurs versus nonmigraineurs in samples collected from the oral cavity and a slight but significant difference in fecal samples. IMPORTANCE Recent work has demonstrated a potentially symbiotic relationship between oral commensal bacteria and humans through the salivary nitrate-nitrite-nitric oxide pathway (C. Duncan et al., Nat Med 1:546-551, 1995, http://dx.doi.org/10.1038/nm0695-546). Oral nitrate-reducing bacteria contribute physiologically relevant levels of nitrite and nitric oxide to the human host that may have positive downstream effects on cardiovascular health (V. Kapil et al., Free Radic Biol Med 55:93-100, 2013, http://dx.doi.org/10.1016/j.freeradbiomed.2012.11.013). In the work presented here, we used 16S rRNA Illumina sequencing to determine whether a connection exists between oral nitrate-reducing bacteria, nitrates for cardiovascular disease, and migraines, which are a common side effect of nitrate medications (U. Thadani and T. Rodgers, Expert Opin Drug Saf 5:667-674, 2006, http://dx.doi.org/10.1517/14740338.5.5.667).

Immune response of the bay scallop, Argopecten irradians, after exposure to the algicide palmitoleic acid

Palmitoleic acid (PA) is an effective algicide against the toxin-producing dinoflagellate Alexandrium tamarense; however, its effects on the immune system of the edible bay scallop Argopecten irradians are unclear. Therefore, we investigated the effects of PA on the immune response in A. irradians by assessing total haemocyte counts (THC), alkaline phosphatase activity (ALP), nitrite oxide (NO), glutathione (GSH), and lactate dehydrogenase (LDH) levels, as well as the expression of immune-related genes (FREP, PGRP, HSP90, MnSOD, and Cu/ZnSOD) at various hours post-exposure (hpe) to the compound. THC decreased in PA-treated groups, whereas ALP increased significantly in all of the PA treatment groups at 3 hpe, after which it significantly decreased. The LDH and NO levels were significantly enhanced in the high and medium concentration group. Notably, the GSH level increased in all PA treatment groups at each time interval. Our study revealed that after treatment with different concentrations of PA, variable effects on the expression of genes involved in the immune system response were observed. The results of our study demonstrate that immersing scallops in PA at effective concentrations could result in differential effects on immune system responses and expression of immune-related genes. Specifically, PA may disrupt the endocrine system or affect signal transduction pathways in the scallops. Therefore, the present study highlights the potential risk of using the PA as an algicide to control algal bloom outbreaks in the marine environment.

Isocyperol, isolated from the rhizomes of Cyperus rotundus, inhibits LPS-induced inflammatory responses via suppression of the NF-κB and STAT3 pathways and ROS stress in LPS-stimulated RAW 264.7 cells

The rhizomes of Cyperus rotundus (cyperaceae) have been used in Korean traditional medicines for treating diverse inflammatory diseases. However, little is known about the biological activities of isocyperol, a sesquiterpene isolated from C. rotundus, and their associated molecular mechanisms. In this study, we found that isocyperol significantly inhibited lipopolysaccharide (LPS)-induced production of nitrite oxide (NO) and prostaglandin E2 (PGE2) and suppressed LPS-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the mRNA and protein levels in RAW 264.7 macrophages. In addition, isocyperol downregulated the LPS-induced expression of several proinflammatory cytokines, such as interleukin-1beta (IL-1β), IL-6, and monocyte chemotactic protein-1 (MCP-1). Isocyperol treatment suppressed the LPS-induced nuclear translocation and transcriptional activation of nuclear factor-kappaB (NF-κB) in macrophages. Moreover, the activation of STAT3, another proinflammatory signal, was suppressed by isocyperol in LPS-stimulated RAW 264.7 cells. Isocyperol pretreatment also induced heme oxygenase-1 (HO-1) expression and reduced LPS-stimulated reactive oxygen species (ROS) accumulation in macrophages. Furthermore, isocyperol significantly increased the survival rate and attenuated serum levels of NO, PGE2, and IL-6 in LPS-induced septic shock mouse model. Taken together, these data indicate that isocyperol suppress septic shock through negative regulation of pro-inflammatory factors through inhibition of the NF-κB and STAT3 pathways and ROS. To our knowledge, this is the first report on the biological activity of isocyperol and its molecular mechanism of action.

Essential Oil from the Heartwood of Taiwan fir Ameliorates LPS-induced Inflammatory Response by Inhibiting the Activation of Mitogen-activated Protein Kinase

The essential oil from the heartwood of Taiwan fir (EOTC) was demonstrated to exhibit anti-inflammatory activity in lipopolysaccharide (LPS)-activated mouse macrophages. EOTC reduced nitrite oxide levels and inducible nitrite oxide synthase expression in, and tumor necrosis factor-α and interleukin-6 secretion by, LPS-activated macrophages without affecting cyclooxygenase-2 expression. EOTC reduced the levels of interleukin-lβ precursor induced by LPS and decreased the NLRP3 inflammasome-derived interleukin-lβ secretion induced by LPS and adenosine triphosphate. In addition, the phosphorylation levels of ERKI/2, JNK1/2, and p38 in LPS-activated macrophages were reduced by EOTC. Furthermore, EOTC was composed of oxygenated sesquiterpenes (68.4%), sesquiterpene hydrocarbons (28.9%) and diterpenes (0.9%). The major compounds of the oxygenated sesquiterpenes were τ-cadinol (23.9%), α-cadinol (21.1%) and cedrol (16.9%). These findings suggest that EOTC may be a candidate for the development of anti-inflammatory agents for preventing and ameliorating inflammation-related diseases.

Antioxidant and anti-inflammatory properties of Dichondra repens Forst. and its reference compounds

Dichondra repens (DR) is the main constituent in herbal beverages and consumed daily as a nutrition supplement for the liver in Taiwan. This study investigated the antioxidant and anti-inflammatory effects of D. repens ethanol extract (EDR) and its reference compounds ex vivo and in vivo. Fingerprint chromatograms (from HPLC) indicated that EDR contained vanillin, umbelliferone and scopoletin. EDR was evaluated for its antioxidant effects and LPS-induced NO production in RAW 264.7 cells. EDR decreased the LPS-induced NO production and expressions of iNOS and COX-2 in RAW 264.7 cells. In vivo anti-inflammatory activities of EDR were assessed in mouse paw oedema, induced by λ-carrageenan (Carr). We investigate the antioxidant mechanism of EDR via studies of the activities of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) in the liver and the levels of malondialdehyde (MDA) and nitrite oxide (NO) in the oedematous paw. Serum NO and TNF-α were also measured. EDR exerts anti-inflammatory effects by suppressing TNF-α, NO, and might be related to the decrement of the level of MDA in the oedema paw via increasing the activities of CAT, SOD and GPx in the liver. The results show that EDR might be a natural antioxidant and anti-inflammatory agent.

Anti-inflammatory effects of methanol extract of Antrodia cinnamomea mycelia both in vitro and in vivo

Antrodia cinnamomea is a folk medicinal mushroom commonly used in Taiwan for the treatment of several types of cancers and inflammatory disorders. This study aimed to explore the folk use of Antrodia cinnamomea on pharmacological grounds to characterize the scientific basis of anti-inflammatory activity. The in vitro anti-inflammatory activity of methanol extract of liquid cultured mycelia of Antrodia cinnamomea (MEMAC) was judged by the measurement of the produced levels of pro-inflammatory cytokines and mediators in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and human peripheral blood mononuclear cells (PBMCs). The in vivo anti-inflammatory activity of MEMAC was evaluated using carrageenan-induced hind paw edema in mice, the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the liver and the levels of malondialdehyde (MDA) and nitrite oxide (NO) in the edema paw. The levels of serum NO and TNF-α were measured. The MEMAC was administered at the concentrations of 100, 200, and 400mg/kg body weight of mouse. MEMAC inhibited the production of LPS-induced pro-inflammatory cytokines (TNF-α and IL-6) and mediators (NO and PGE2) in RAW264.7 cells and human PBMCs. Data from Western blotting showed that MEMAC decreased the levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression in LPS-stimulated RAW264.7 macrophages. In vivo, MEMAC showed significant (p<0.05) anti-inflammatory activity by reducing the edema volume in carrageenan-induced paw edema in mice. MEMAC (400mg/kg) also reduced the carrageenan-induced leukocyte migration (50.92±5.71%). Further, MEMAC increased the activities of CAT, SOD, and GPx in the liver tissue and decreased the levels of serum NO and TNF-α after carrageenan administration. Our results showed that MEMAC has the anti-inflammatory property both in vitro and in vivo, suggesting that it may be a potential preventive or therapeutic candidate for the treatment of inflammatory disorders.

Antioxidant and anti-inflammatory properties of Cardiospermum halicacabum and its reference compounds ex vivo and in vivo

Cardiospermum halicacabum (CH) has been used in Chinese medicine for a long time. However, its fingerprint chromatogram, antioxidant, anti-inflammatory effects and mechanism are still needed to be explored. Therefore, the aims of this study investigated the antioxidant and anti-inflammatory effects of CH extracts and its reference compounds ex vivo and in vivo. In HPLC analysis, the fingerprint chromatogram of ethanolic extract of CH (ECH) was established. The effects of ACH (aqueous extract of CH) and ECH extracts were assessed for the antioxidant and LPS-induced NO production in RAW264.7 cells. In vivo anti-inflammatory activities of ECH were evaluated in mouse paw edema induced by λ-carrageenan (Carr). We investigate the anti-inflammatory mechanism of ECH via studies of the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the liver and the levels of malondialdehyde (MDA) and nitrite oxide (NO) in the edema paw. Serum NO and TNF-α were also measured. ECH had better antioxidant activity than that of ACH. In the anti-inflammatory test, ECH inhibited the development of paw edema induced by Carr and increased the activities of CAT, SOD and GPx in the liver tissue. ECH also decreased the level of NO in edematous paw tissue and in serum level, and diminished the level of serum TNF-α at the fifth hour after Carr injection. ECH exerts anti-inflammatory effects by suppressing TNF-α and NO. The anti-inflammatory mechanism of ECH might be related to the decrement of the level of MDA in the edema paw via increasing the activities of CAT, SOD and GPx in the liver. The results showed that ECH might serve as a natural antioxidant and anti-inflammatory agent.

The Effect of Melatonin Against FK506-Induced Renal Oxidative Stress in Rats

Nephrotoxicity is an important side effect of FK506 and oxidative stress has been considered as one of the possible mechanisms. The present investigation examines the ability of melatonin to protect against FK506-induced renal oxidative stress. Thirty rats were divided into 3 groups (n = 10 each group). Group A was the sham group. Group B received 14 days FK506 (5 mg/kg/d, intraperitoneally [i.p.]) and group C received FK506 (5 mg/kg/d, i.p.) together with melatonin (4 mg/kg, i.p.) for 14 days. Kidney tissues were harvested to determine the tissue levels of malondialdehyde (MDA), total nitrite and nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). In group C, the levels of TNF-α, IL-6, and NO were lower than in the group B (P < .01, P < .03, and P < .04, respectively) and although MDA levels were lower than in group B, the differences were not statistically significant (P > .05). These results suggest that melatonin has protective effect against FK506-induced renal oxidative stress.

The antioxidant role of oral administration of garlic oil on renal ischemia–reperfusion injury

Aim: In this study we examined the effect of oral application of garlic form [garlic oil (GO)] on rats after renal ischemia–reperfusion (I/R) injury. Materials and methods: Forty male Wistar albino rats were divided into four groups: control, sham-operated, I/R, and I/R + GO. GO was diluted in water and administered by oral intubation three times each week for 6 weeks. All rats except sham-operated underwent 45 min of bilateral renal ischemia followed by 6 hr of reperfusion. Blood samples and kidney tissues were harvested from the rats, and then rats were killed. Serum urea, creatinine, and cystatin C levels were determined. Total antioxidant capacity (TAC), catalase (CAT), total oxidant status (TOS), oxidative stress index (OSI), myeloperoxidase (MPO), nitrite oxide (NO), and protein carbonyl (PC) levels in kidney tissue and blood were measured. In addition, kidney tissue histopathology was evaluated. Results: The serum urea, creatinine, and cystatin C levels were significantly higher in I/R group compared to I/R + GO group (p < 0.01). The serum and tissue antioxidant markers (TAC, CAT) were significantly lower in I/R group than I/R + GO group (p < 0.01). The serum oxidant markers (TOS, MPO, NO, and PC) were significantly higher in I/R group than I/R + GO group (p < 0.01). Also oral application of GO was effective in decreasing of tubular necrosis score. Conclusion: Based on the present data, we conclude that increased antioxidants and decreased oxidants modulated by oral application of GO attenuated the renal I/R injury.

Effects of nebivolol therapy on endothelial functions in cardiac syndrome X

Endothelial dysfunction is major pathophysiologic mechanism in cardiac syndrome X (CSX), which causes a decrease in plasma nitrite oxide (NO) levels. It was demonstrated that nebivolol improves endothelial function and increases NO release. Despite this pathophysiologic relation, the effect of nebivolol therapy on endothelial function in patients with CSX is unknown. The aim of this study is to evaluate the effect of nebivolol on patients in CSX. Thirty-eight patients who were diagnosed with CSX were prospectively enrolled in the study. The treatment group consisted of 20 patients and the control group consisted of 18 patients. An oral 5-mg dose of nebivolol was given daily and maintained for 4 weeks in the treatment group. Ultrasonographic parameters (brachial artery flow-mediated dilatation [FMD], brachial artery lumen diameters) and inflammatory markers (high-sensitivity C-reactive protein [hsCRP], von Willebrand factor [vWf], and fibrinogen) were measured at baseline and end of the 4 weeks. Brachial baseline lumen diameter, brachial lumen diameter after reactive hyperemia, and FMD were 4.61 +/- 0.49 mm, 4.87 +/- 0.53 mm, and 5.6% +/- 2.3% at baseline. After the nebivolol therapy, there was a significant increase in both brachial artery baseline lumen diameter and lumen diameter after reactive hyperemia (P < 0.001 and P = 0.002). However, there was no significant change in FMD (5.6% +/- 2.2% vs 5.3% +/- 2.1%, P not significant). Levels of hsCRP, vWf, and fibrinogen were significantly decreased (hsCRP: 3.4 +/- 0.49 mg/dl vs 2.97 +/- 0.74 mg/dl, P = 0.001; vWf: 107 +/- 62 vs 86 +/- 58, P = 0.004; fibrinogen: 341 +/- 89 mg/dl vs 299 +/- 87 mg/ dl, P = 0.01) in the treatment group. Nebivolol therapy may have a favorable effect on endothelial function in CSX. Further studies are needed to confirm the clinical significance of nebivolol therapy in CSX.

Analgesic and anti-inflammatory activities of a water extract of Trachelospermum jasminoides (Apocynaceae)

Aims of the study This study investigated the analgesic and anti-inflammatory effects of a water extract of Trachelospermum jasminoides (WET) in ICR mice. Materials and methods In HPLC analysis, the fingerprint chromatogram of WET was established. Acetic acid-induced writhing response and formalin-induced pain were examined the analgesics effects of WET. WET on λ-Carrageenan(carr)-induced paw edema was performed. We investigate the anti-inflammatory mechanism of WET via studies of the activities of glutathione peroxidase (GPx), glutathione reductase (GRx) in the liver and the levels of malondialdehyde (MDA) and nitrite oxide (NO) in the edema paw. Serum NO and TNF-α were also measured. Results The fingerprint chromatogram of WET was established through HPLC analysis, and implies that WET contains the active ingredient gallic acid, chlorgenic acid, caffeic acid, taxifolin, isoquercitrin and quercetin. WET significantly inhibited the numbers of acetic acid-induced writhing responses and the formalin-induced pain in the late phase. In the anti-inflammatory test, WET inhibited the development of paw edema induced by carr. WET decreased the paw edema at the third, fourth and fifth hour after carr administration, and increased the activities of SOD, GPx and GRx in the liver tissue and decreased the MDA level in the edema paw at the third hour after carr injection. WET decreased the level of NO in edematous paw tissue and in serum level, and diminished the level of serum TNF-α at the fifth hour after carr injection. Conclusions These results demonstrated that WET is an effective anti-inflammatory agent in carr-induced inflammation. WET probably exerts anti-inflammatory effects by suppressing TNF-α and NO. The anti-inflammatory mechanism of WET might be related to the decrease in the level of MDA in the edema paw via increasing the activities of SOD, GPx and GRx in the liver.

Ameliorative Potential of Spironolactone in Diabetes Induced Hyperalgesia in Mice

The present study was designed to investigate the ameliorative potential of spironolactone against diabetic hyperalgesia in mice. Tail flick latency, an index of hyperalgesia, was assessed by analgesiometer. Serum nitrite levels, an index of nitric oxide, were analyzed by Griess reaction. Mice were rendered diabetic with streptozotocin (200 mg kg(-1) i.p) and kept for 30 days for development of diabetic pain. Thereafter, spleen homogenate supernatant (SHS) was prepared from the mouse spleen and administered in normal mice for 14 days. In both diabetic and SHS-treated mice a significant degree of hyperalgesia was developed, suggesting the key role of spleen-derived factor in induction of diabetic pain. Moreover, the levels of nitric oxide were also elevated in 30th day diabetic mice and SHS-treated mice. Administration of spironolactone (7 and 15 mg kg(-1) p.o.) significantly attenuated diabetes-induced decrease of nociceptive threshold and increase of serum nitrite oxide levels. Furthermore, SHS of spironolactone-treated diabetic mice failed to induce hyperalgesia and to increase serum nitrite levels. These results suggest that spironolactone has ameliorative potential in attenuating the hyperalgesia associated with diabetes, which may be possibly mediated through inhibition of release of certain critical factors from spleen.

Effects of serum homocysteine and adiponectin levels on platelet aggregation in untreated patients with essential hypertension

The aim of the present study is to determine and correlate adiponectin, homocysteine, nitric oxide, and ADP-induced platelet aggregation levels in untreated patients with essential hypertension and healthy individuals. A total of 36 individuals, 23 untreated patients with essential hypertension and 13 healthy individuals, were included in the scope of this study. Enzyme-linked immunosorbent assay (ELISA) was used to determine the serum adiponectin and TNF-alpha levels. The levels of serum homocysteine were measured by using competitive chemiluminescent enzyme immunoassay. Serum concentrations of hsCRP were measured by the Nephelometer. Plasma nitrite, nitrate, and total nitric oxide (NOx) levels were determined by colorimetric method. Homocysteine and hsCRP levels in patients with essential hypertension were found to be significantly higher than those in the control group (P = 0.02, P = 0.001, respectively). The average platelet aggregation levels in patient group were higher than control group, but there were no statistically significant differences between them (P > 0.05). In addition, in patients with essential hypertension adiponectin and nitrite levels are significantly lower than control group (P < 0.001, P = 0.045, respectively). We have also found significant correlations between nitrite-platelet aggregation amplitude, nitrite-platelet aggregation slope, nitrite-adiponectin, homocysteine-platelet aggregation amplitude, and sistolic blood pressure-platelet aggregation amplitude levels (r = -0.844; P < 0.001, r = -0.680; P = 0.011, r = 0.454; P = 0.05, r = 0.414; P = 0.05, r = 0.442; P = 0.035, respectively). Increased homocysteine and decreased adiponectin serum levels in patients with essential hypertension correlate well with changes in ADP-induced conventional platelet aggregation. This association may potentially contribute to future thrombus formation and higher risks for cardiovascular events in hypertensive patients.

Possible Role of Spleen Derived Factors, Vanilloid Receptors and Calcitonin Gene-related Peptide in Diabetes Induced Hyperalgesia in Mice

The present study was designed to investigate a possible role of vanilloid receptors, CGRP and spleen in the induction of diabetes induced hyperalgesia in mice. Tail flick latency, an index of hyperalgesia, was assessed using analgesiometer. Serum nitrite levels and an index of nitric oxide were analyzed using Griess reaction. Mice were rendered diabetic with streptozotocin (200 mg/kg(-1), i.p.) and kept for 30 days for development of diabetic pain. To explore the involvement of spleen in diabetic pain, spleen homogenate supernatant (SHS) was prepared from spleen of 30th day diabetic mice and administered in normal mice for 14 days. Both in diabetic and SHS treated mice, significant degree of hyperalgesia was developed, suggesting the possible role of spleen derived factor in induction of diabetic pain. Moreover, the levels of nitric oxide were also elevated in 30 day diabetic mice and SHS treated mice. Administration of ruthenium red (1 mg/kg(-1), i.p.), vanilloid receptor antagonist, and sumatriptan (50 mg/kg(-1), i.p.), a CGRP release inhibitor, attenuated diabetes and SHS induced decrease in nociceptive threshold and increase in serum nitrite oxide levels. These results suggest that spleen derived factor induced activation of vanilloid receptors and CGRP release may be contributing in the development of hyperalgesia in diabetic mice.

Does pinealectomy affect the recovery rate after spinal cord injury?

Previous reports documented demonstrated that melatonin, a free radical scavenger, is important in protecting against oxidative stress-induced tissue damage after spinal cord injury (SCI). This study was undertaken to investigate the effects of pinealectomy (PX) and administration of exogenous melatonin after SCI in rats.These animals were randomized into six groups, each having 12 rats. Group 1 underwent laminectomy alone. Group 2 underwent laminectomy followed by SCI and received no medication. Group 3 underwent laminectomy followed by SCI and received melatonin. Group 4 underwent PX and laminectomy alone. Group 5 underwent PX and laminectomy followed by SCI and received no medication. Group 6 underwent PX and laminectomy followed by SCI and received melatonin. Melatonin (100 mg/kg) was given intraperitoneally immediately after trauma to the rats in the groups 3 and 6.PX caused a significant increase in the malondialdehyde (MDA), nitrite oxide (NO), glutathione (GSH), xanthine oxidase (XO) levels and decrease in GSH levels as compared with the control group. Trauma to the spinal cord results in significantly higher oxidative stress. Melatonin administration significantly reduced MDA, XO and NO levels, and increased GSH levels in the spinal cord after trauma. Exogenous melatonin treatment after trauma attenuated tissue lesion area and accelerated motor recovery rate. These findings suggest that reduction in endogenous melatonin after PX makes the rats more vulnerable to trauma and exogenous melatonin administration has an important neuroprotective effect on the level of the spinal cord.

NITRIC OXIDE MODULATES AIR EMBOLISM‐INDUCED LUNG INJURY IN RATS WITH NORMOTENSION AND HYPERTENSION

1. Air embolism the in lungs induces microvascular obstruction, mediator release and acute lung injury (ALI). Nitrite oxide (NO) plays protective and pathological roles in ALI produced by various causes, but its role in air embolism-induced ALI has not been fully investigated. 2. The purpose of the present investigation was to elucidate the involvement of NO and pro-inflammatory cytokines in the pathogenesis of ALI following air infusion into isolated perfused lungs from spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) rats. 3. The extent of ALI was evaluated by changes in lung weight, Evans blue dye leakage, the protein concentration in the bronchoalveolar lavage and pathological examination. We also measured nitrite/nitrate (NO(x)), tumour necrosis factor (TNF)-alpha and interleukin (IL)-1beta concentrations in lung perfusate and determined cGMP in lung tissue. 4. The NO synthase (NOS) inhibitors N(G)-nitro-l-arginine methyl ester (l-NAME) and l-N(6)-(1-iminoethyl)-lysine (l-Nil), as well as the NO donors sodium nitroprusside (SNP) and s-nitroso-N-acetylpenicillamine (SNAP), were administered 30 min before air embolism at a concentration of 10(-3) mol/L in the lung perfusate. 5. Air embolism-induced ALI was enhanced by pretreatment with l-NAME or l-Nil, but was alleviated by SNP or SNAP pretreatment, in both SHR and WKY rats. In both SHR and WKY rats, AE elevated levels of NO(x) (2.6 and 28.7%, respectively), TNF-alpha (52.7 and 158.6%, respectively) and IL-1beta (108.4 and 224.1%, respectively) in the lung perfusate and cGMP levels in lung tissues (35.8 and 111.2%, respectively). Pretreatment with l-LAME or l-Nil exacerbated, whereas SNP or SNAP abrogated, the increases in these factors, except in the case of NO(x) (levels were decreased by l-LAME or l-Nil pretreatment and increased by SNP or SNAP pretreatment). 6. Air embolism caused increases in the lung weight (LW)/bodyweight ratio, LW gain, protein concentration in bronchoalveolar lavage and Evans blue dye leakage. These AE-induced changes were less in lungs isolated from SHR compared with normotensive WKY rats. 7. The results suggest that ALI and associated changes following air embolism in lungs isolated from SHR are less than those in WKY rats. Nitric oxide production through inducible NOS isoforms reduces air embolism-induced lung injury and associated changes. Spontaneously hypertensive rats appear to be more resistant than WKY rats to air embolism challenge.