The Protection Potential of Antioxidant Vitamins Against Acute Respiratory Distress Syndrome: a Rat Trial.

Acute respiratory distress syndrome (ARDS) is a fatal disease that includes inflammation formed by septic and non-septic causes. Reactive oxygen radicals (ROS) play a key role in ARDS pathophysiology and constitute the base of damage process. Antioxidant vitamins are used for inhibiting hazardous effects of radicals. Therefore, effects of antioxidant vitamins such as α-lipoic acid (ALA), vitamin E (VITE), and C (VITC) were investigated on oleic acid (OA)-induced ARDS rat model. Furthermore, high and low dose of methylprednisolone (HDMP, LDMP) was used for comparing effects of the vitamins. In this study, 42 male rats were divided to seven groups named control, OA, ALA, VITE, VITC, LDMP, and HDMP. OA was intravenously administered to all groups except control group and other compounds were orally administered (ALA, VITE, and VITC: 100 mg/kg, LDMP: 5 mg/kg, HDMP: 50 mg/kg) after OA injections. OA increased MDA level in lung tissue and TNF-α and IL-1ß cytokine levels in serum. ALA, VITE, VITC, and both dose of MP significantly decreased the cytokine levels. Although OA reduced SOD, CAT, and GSH levels in lung tissue, the vitamins and LDMP markedly enhanced the levels except for HDMP. Furthermore, OA showed thickening in bronchi and alveolar septum, hyperemia in vessels, and inflammatory cell infiltrations in lung tissue histopathological examinations. Antioxidant vitamins may be useful for premedication of ARDS and similar disorders. However, methylprednisolone was not found sufficient for being a therapeutic agent for ARDS.

Anti-inflammatory and antioxidant properties of jervine, a sterodial alkaloid from rhizomes of Veratrum album.

BACKGROUND: Veratrum, hellebore is an important plant species of the Liliaceae family and jervine is the characteristic steroidal alkaloid constituent of Veratrum album. PURPOSE: In the current study, anti-inflammatory and antioxidant effects of jervine isolated from NH4OH-benzene extract of V. album rhizomes were investigated on CAR induced paw edema in rats. METHODS/STUDY DESIGN: In inflammatory study, 50, 100, 200 and 400  mg/kg doses of jervine, 25  mg/kg doses of DIC and IND were orally administered, and the volume of the foots were measured up to their knee arthrosis by plethismometer. After one hour of the oral administration of the all treatments, 0.1 ml of CAR solution (1%) was injected into the foot of the all rat groups and the volume of the foots were measured during 5 h after CAR injection. GPx, SOD, GR, MPO, CAT enzymes activities and GSH, LPO levels of the supernatants of paw homogenates and inflammation biomarkers such as TNF-α and IL-1ß in the rats serums were also estimated. RESULTS: According to the present results, jervine exerted 50.4-73.5% anti-inflammatory effects in carrageenan induced paw edema. Inflammation biomarkers such as TNF-α, IL-1ß and MPO that increased by CAR injection were suppressed by the administrations of all doses of jervine, IND and DIC. In all paw tissues, LPO levels as indicator of oxidative tissue damage were found to be high in CAR-treated group and it was found to be decreased in all doses of jervine. CONCLUSION: Jervine, DIC and IND reduced the negative effects of CAR due to increasing effects on the SOD, CAT, GSH, GPx and GR antioxidants.

A novel therapeutics agent: antioxidant effects of hydroxylfasudil on rat kidney and liver tissues in a protamine sulphate-induced cystitis rat model; preliminary results.

Cystitis is defined as an inflammation of the bladder caused by a bacterial infection, and it can be dangerous and painful when it spreads through the internal organs. In this study, antioxidant effects of hydroxylfasudil (HF) at the enzymatic and molecular level on kidney and liver tissues in cystitis rat model, which is caused by inflammation of the rat bladder with a protamine sulphate (PS), was examined. Quantitative changes of reduced glutathione (GSH) and lipid peroxidation (LPO) levels, which are a marker for oxidative stress, were determined in rat kidney and liver tissues for each groups. And then molecular and biochemical impact of HF treatment on antioxidant enzymes including superoxide dismutase (SOD) and catalase (CAT) in cystitis model were studied. The results suggest that HF could be beneficial to the renal and hepatic antioxidant system. Thus, HF might be used as a novel therapeutics agent to eliminate interstitial cystitis.

Natural product inhibitors of carbonic anhydrase I and II isoenzymes: osajin and pomiferin.

The aim of this study is to purify carbonic anhydrase I and II isoenzymes from human erythrocyte, isolate two natural products osajin (OSJ) and pomiferin (PMF) from Maclura pomifera fruits, and evaluate the in vitro effect of these natural metabolites on these isoenzymes. These natural products may be used as starting points for drug discovery (like drugs used in several therapeutic applications, including antiglaucoma activity). For the purification procedure, the Sepharose-4B-l-tyrosine-sulphonamide affinity chromatography was used. Column chromatography and thin layer chromatography methods were used for isolation of OSJ and PMF from M. pomifera fruits and their chemical structures were elucidated by IR, 1D, and 2D NMR methods. We compared inhibitory effects of these natural products with inhibitory effects of phenolic compounds and found that these products demonstrated average inhibition effects. We thought that this study will give inspiration to scientists interested in this issue.

Melatonin Attenuates Contrast-Induced Nephropathy in Diabetic Rats: The Role of Interleukin-33 and Oxidative Stress.

BACKGROUND: Inflammation and oxidative stress (OxS) contribute to the pathogenesis of diabetic kidney disease (DKD) and contrast-induced nephropathy (CIN). Patients with DKD were found to be more prone to CIN. Interleukin-33 (IL-33) is a proinflammatory cytokine, but its role in DKD and CIN is unknown. METHODS: Thirty male Sprague-Dawley rats were enrolled. The first group was comprised of healthy rats (HRs), whereas the other four groups were made up of diabetic rats (DRs), diabetic rats with contrast-induced nephropathy (CIN + DRs), melatonin-treated diabetic rats (MTDRs), and melatonin-treated CIN + DRs (MTCIN + DRs). All groups except the HRs received 50 mg/kg/day streptozotocin (STZ). CIN + DRs were constituted by administrating 1.5 mg/kg of intravenous radiocontrast dye on the 35th day. MTDRs and MTCIN + DRs were given 20 mg/kg/day of intraperitoneal injection of melatonin (MT) from the 28th day for the constitutive seven days. RESULTS: We observed increased IL-33 in the kidney tissue following induction of CIN in DRs. To determine whether MT is effective in preventing CIN, we administered MT in CIN + DRs and demonstrated that kidney tissue levels of OxS markers, inflammatory cytokines, and IL-33 were significantly diminished in MTCIN + DRs compared with other groups without MT treatment (p < 0.05). CONCLUSION: Inhibition of IL-33 with MT provides therapeutic potential in DKD with CIN.

N-Acetyl Cysteine Has Both Gastro-Protective and Anti-Inflammatory Effects in Experimental Rat Models: Its Gastro-Protective Effect Is Related to Its In Vivo and In Vitro Antioxidant Properties.

N-acetyl cysteine (NAC), a metabolite of sulphur-containing amino acid cysteine, is used as an antioxidant and a mucolytic agent. Therefore, we aimed to investigate anti-inflammatory and anti-ulcerative effects of NAC. We also intended to determine the relation between antiulcer effect of NAC and its antioxidant properties by biochemical evaluation. In this study a total of 15 rat groups (n = 6 per group) were used for inflammation and ulcer experiments. Anti-inflammatory effects of NAC have been investigated on six rat groups with carrageenan (CAR)-induced paw oedema model. Antiulcer effects of NAC have been investigated on 24 h fasted nine rat groups with IND-induced ulcer model in the presence of positive (LAN, RAN, FAM, and OMEP), negative (untreated IND group) and intact control groups. In biochemical analyses of stomach tissues; glutathione S-transferase (GST), catalase (CAT), myeloperoxidase (MPO), and superoxide dismutase (SOD) enzyme activities and lipid peroxidation (LPO) and the glutathione (GSH) levels were determined. All doses of NAC exerted significant anti-inflammatory effect; even the effect of 900 mg/kg NAC was similar with that of DIC and IND. In gastric tissues NAC administration decreased the level of LPO and activity of CAT, which were increased by IND. Furthermore, NAC increased the GSH level and SOD and GST activities, which decreased in ulcerous stomach tissues. Only MPO activity increased in both IND and NAC groups when compared to healthy rat group. We determined that NAC has both anti-inflammatory and anti-ulcerative effects.

Impact of Rho-Kinase Inhibitor Hydroxyfasudil in Protamine Sulphate Induced Cystitis Rat Bladder.

OBJECTIVES: The objective of the present study was to evaluate anti-inflammatory effects of hydroxyfasudil in a protamine sulfate (PS) induced cystitis rat model. Additionally, we investigated prevention of bladder overactivity (BO), and tissue damage in these experiments. METHODS: Animals were divided into four groups. In Groups 1 and 2, chemical induced cystitis model was created by administrating intravesical PS with PE50 catheter by the transurethral route. In Group 1, Rho-kinase inhibitor hydroxyfasudil was administered intaperitoneally, and in Group 2, subjects were administered a corresponding volume of saline in the same way. In Group 3, vehicle was administered intravesically and hydroxyfasudil was administrated intraperitoneally. Group 4 was a control Group, and the vehicle was administered intravesically and intraperitoneally. Micturition frequencies were recorded. Biochemical analyses were performed for oxidative stress, and pathological evaluations were investigated. In vitro contractions of bladder tissue strips were measured in tissue-bath. RESULTS: There were significantly lower Lipid peroxidase levels and higher levels of Glutathione in Group 1 than Group 2 (P = 0.016, P = 0.001, respectively). There was generally more inflammation in Group 2 than the other groups as determined by microscopy. There were significantly higher frequencies of micturition, lower volume, and mean voided maximum urine output after PS administration in Groups 1 and 2. In vitro contraction responses of bladder strips to potassium chloride and acetylcholine were statistically higher in Group 2 than Groups 1 and 3. CONCLUSIONS: Significant reduction of inflammation by affecting the anti-oxidant defense systems was provided by hydroxyfasudil. Decreased in vitro responses to contractions of bladder smooth muscle strips were obtained. Hydroxyfasudil may be a potential new therapeutic option for inflammation and BO, in rat bladder.

Gastroprotective and Antioxidant Effects of Lobaria pulmonaria and Its Metabolite Rhizonyl Alcohol on Indomethacin-Induced Gastric Ulcer.

Two lichen metabolites, rhizonaldehyde (1) and rhizonyl alcohol (2), were isolated from the acetone extract of Lobaria pulmonaria by chromatographic methods, and their chemical structures were determined by UV/VIS, IR, and 1D- and 2D-NMR spectroscopic methods. The gastroprotective and in vivo antioxidant activities of extracts of L. pulmonaria and its metabolites, 1 and 2, were investigated in indomethacin-induced ulcer models in rats. The gastric lesions were significantly reduced by acetone, hexane, and CHCl3 extracts, with 75.3-41.5% inhibition. Rhizonyl alcohol (2) significantly reduced the gastric lesions with an inhibition rate of 84.6-42.8%, whereas rhizonaldehyde (1) significantly increased the gastric lesions. Antioxidant parameters and myeloperoxidase activities were also evaluated in the gastric tissues of the rats. Indomethacin caused oxidative stress, which resulted in lipid peroxidation in gastric tissues by decreasing the levels of the antioxidants as compared to healthy rat tissues. In contrast to indomethacin, all extracts and rhizonyl alcohol (2) caused a significant decrease in lipid peroxidation levels and an increase in antioxidant parameters, superoxide dismutase, glutathione peroxidase, and glutathione-S-transferase, and reduced glutathione in gastric tissues. The administration of rhizonyl alcohol (2) also resulted in a decrease in gastric myeloperoxidase activity increased by indomethacin. The gastroprotective effect of rhizonyl alcohol (2) can be attributed to its antioxidant properties and its suppressing effect on neutrophil infiltration into gastric tissues.

Neurotoxic effects of nickel chloride in the rainbow trout brain: Assessment of c-Fos activity, antioxidant responses, acetylcholinesterase activity, and histopathological changes.

The aim of this study was to determine the biochemical, immunohistochemical, and histopathological effects of nickel chloride (Ni) in the rainbow trout brain. Fish were exposed to Ni concentrations (1 mg/L and 2 mg/L) for 21 days. At the end of the experimental period, brain tissues were taken from all fish for c-Fos activity and histopathological examination and determination of acetylcholinesterase (AChE), superoxide dismutase (SOD), catalase (CAT) enzyme activities, lipid peroxidation (LPO), and glutathione (GSH) levels. Our results showed that Ni treatment caused a significant increase in the brain SOD activity and in LPO and GSH levels (p < 0.05), but it significantly decreased AChE and CAT enzyme activities (p < 0.05). Strong induction in c-Fos was observed in some cerebral and cerebellar regions of fish exposed to Ni concentrations when compared with the control group. However, c-Fos activity was decreased in necrotic Purkinje cells. Brain tissues were characterized by demyelination and necrotic changes. These results suggested that Ni treatment causes oxidative stress, changes in c-Fos activity, and histopathological damage in the fish brain.

Alpha-lipoic acid protects against indomethacin-induced gastric oxidative toxicity by modulating antioxidant system.

Gastroprotective effects of α-lipoic acid (ALA) against oxidative gastric damage induced by indomethacin (IND) have been investigated. All doses (50, 75, 100, 150, 200, and 300 mg/kg body weight) of ALA reduced the ulcer index with 88.2% to 96.1% inhibition ratio. In biochemical analyses of stomach tissues, ALA administration decreased the level of lipid peroxidation (LPO) and activities of myeloperoxidase (MPO) and catalase (CAT) in gastric tissues, which were increased after IND application. ALA also increased the level of glutathione (GSH) and activities of superoxide dismutase (SOD) and glutathione S-transferase (GST) that were decreased in gastric damaged stomach tissues. In conclusion, the gastroprotective effect of ALA could be attributed to its ameliorating effect on the antioxidant defense systems.

Diffractaic acid, a novel proapoptotic agent, induces with olive oil both apoptosis and antioxidative systems in Ti-implanted rabbits.

Usnea longissima Ach., a lichen species, is a traditional herbal medicine with anti-detrimental effects. We evaluated the in vivo effects of a major constituent of U. longissima, diffractaic acid, and the main fatty component of the Mediterranean diet, olive oil, against apoptosis, including various caspase activations and oxidative injury in surrounding tissues after titanium implantation in rabbit femurs. Furthermore, we evaluated the underlying molecular mechanisms. In this study, this lichen metabolite and olive oil activated caspase-dependent cell death with apoptotic morphology, which is distinctly different from necrosis. Both orally and locally administered olive oil and diffractaic acid exerted pro-apoptotic induction in tissues surrounding the implants in titanium-implanted rabbits through the activation of initiator caspases (Cas-2, -8 and -9) and executioner caspase (Cas-3). In addition, they displayed strong myeloperoxidase and inducible nitric oxide synthase activities, providing an alleviating effect. Furthermore, administrations of diffractaic acid and olive oil attenuated the Ti-alloy implantation, and decreased superoxide dismutase activity and total glutathione level in peri-implant tissues. These results demonstrate that diffractaic acid and olive oil are involved in the induction of apoptotic cell death both through caspase-dependent cell death and as an antioxidant. Thus, the data suggest that both diffractaic acid and olive oil could be developed as effective proapoptotic agents in various disorders treatments.

Effects of diabetes mellitus on the rat liver during the postmenopausal period.

The present study investigated whether diabetes worsened the onset of liver injury/damage during the ovariectomized (OVX)-induced postmenopausal period in rats. Diabetes results in severe complications in humans, such as liver failure. Estrogen and its derivatives are medically acceptable, powerful antioxidant agents that can enable liver and other important organs to defend themselves against oxidative related injury. Estrogen deficiency, which occurs in the postmenopausal period and in individuals with diabetes, may play a significant role in the progression of liver failure. In the present study, rats were divided into four groups: control (Group I), diabetic (Group II), ovariectomy (Group III) and ovariectomy plus diabetes (Group IV). After the experiments, quantitative histopathological and immunohistochemical changes in liver were detected using light microscopy and modern stereological systems. Histopathological examinations showed that there were many necrotic and apoptotic hepatocytes in the lobules of Group II. In addition, there were a larger number of necrotic cells in Group III than Group II. In contrast to Group II, there were also apoptotic cells in the portal areas in Group III. Moreover, evidence of liver injury was higher in the sections of Group IV compared with all other groups. In biochemical findings, there were statistically significant differences between all the groups (P < 0.001) for catalase (CAT), glutathione peroxidase (GSH) and myeloperoxidase (MPx) activity. In addition, the amount of lipid peroxidation (LPO) was significantly different between groups. In stereological results, there were significant differences between Groups I and II and Groups II and IV. The present study provided novel insight into the pernicious effects of ovariectomy on liver injury following the onset of diabetes. Indeed, the present study found that increases in liver oxidative activity in OVX rats following the onset of diabetes correlates with elevated MPx, LPO and histopathological changes in rat liver.

α-Lipoic acid has anti-inflammatory and anti-oxidative properties: an experimental study in rats with carrageenan-induced acute and cotton pellet-induced chronic inflammations.

α-Lipoic acid (ALA) has been termed the 'ideal' antioxidant, a readily absorbed and bioavailable compound capable of scavenging a number of free radicals, and it has been used for treating diseases in which oxidative stress plays a major role. The present study was designed to gain a better understanding for the positive effects of ALA on the models of acute and chronic inflammation in rats, and also determine its anti-oxidative potency. In an acute model, three doses of ALA (50, 100 and 200 mg/kg) and one dose of indomethacin (25 mg/kg) or diclofenac (25 mg/kg) were administered to rats by oral administration. The paw volumes of the animals were calculated plethysmometrically, and 0·1 ml of 1 % carrageenan (CAR) was injected into the hind paw of each animal 1 h after oral drug administration. The change in paw volume was detected as five replicates every 60 min by plethysmometry. In particular, we investigated the activities of catalase, superoxide dismutase (SOD), glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR), inducible NO synthase (iNOS) and myeloperoxidase (MPx), and the amounts of lipid peroxidation (LPO) or total GSH in the paw tissues of CAR-injected rats. We showed that ALA exhibited anti-inflammatory effects on both acute and chronic inflammations, and a strongly anti-oxidative potency on linoleic acid oxidation. Moreover, the administration of CAR induced oedema in the paws. ALA significantly inhibited the ability of CAR to induce: (1) the degree of acute inflammation, (2) the rise in MPx activity, (3) the increases of GST and iNOS activities and the amount of LPO and (4) the decreases of GPx, GR and SOD activities and the amount of GSH. In conclusion, these results suggest that the anti-inflammatory properties of ALA, which has a strong anti-oxidative potency, could be related to its positive effects on the antioxidant system in a variety of tissues in rats.

Alpha-lipoic acid as a potential target for the treatment of lung injury caused by cecal ligation and puncture-induced sepsis model in rats.

One of the common lethal complications of septic shock, a major cause of morbidity and mortality in patients with severe trauma and so on, is acute lung injury. alpha-Lipoic acid (ALA), with antioxidant properties, is a popular agent. Thus, we investigated the potential protective effects of ALA (200 mg/kg) on sepsis-induced acute lung injury. Rats were exposed to cecal ligation and puncture (CLP) to induce sepsis. Rat groups were designed as (a) sham operated, (b) sham operated + ALA treated, (c) CLP applied, (d) CLP + ALA treated. Sixteen hours after CLP induction, serum samples and lung tissues were obtained for biochemical and histopathological examination. alpha-Lipoic acid decreased the serum levels of inflammatory cytokines such as TNF-alpha and IL-6, which increased after CLP. Increased activity of nuclear factor kappaB in septic lung tissues was decreased by ALA. alpha-Lipoic acid improved the decreased antioxidant activity and alleviated the increased oxidant activity, which occurred after CLP application. We can suggest that ALA showed beneficial effects by decreasing nuclear factor kappaB activation in lung tissues, resulting in decreased serum levels of TNF-alpha and IL-6, and also increasing the antioxidant capacity of the lungs.

Protective effects of telmisartan on ischemia/reperfusion injury of rat ovary: biochemical and histopathologic evaluation.

OBJECTIVE: To evaluate the effects of telmisartan as an antioxidant and for its tissue protective properties and to study the biochemical and histopathologic changes in experimental ischemia and ischemia/reperfusion injuries in rat ovaries. DESIGN: Experimental study. SETTING: Experimental surgery laboratory in a university department. ANIMAL(S): Forty-eight female adult rats. INTERVENTION(S): I: sham operation; II: bilateral ovarian ischemia; III: 3 h ischemia + 3 h reperfusion. IV and V: Rats were administered 10 and 20 mg/kg doses of telmisartan, respectively, before 0.5 h of ischemia, and then ovarian ischemia was applied; after 3 h of ischemia, the ovaries were removed. VI and VII: 3 h ovarian ischemia was applied; 2.5 h after the induction of ischemia, rats were administered the same doses of telmisartan; at the end of 3 h of ischemia, the ovaries were removed and a 3 h reperfusion followed. MAIN OUTCOME MEASURE(S): Superoxide dismutase, inducible nitric oxide synthase, and myeloperoxidase activity in rat ovarian tissue; and histopathologic changes in the ovarian tissue of the rats. RESULT(S): Ischemia and ischemia-reperfusion increased the inducible nitric oxide synthase and myeloperoxidase activity while decreasing the super oxide dismutase activity significantly in comparison with the sham group. Before ischemia and ischemia/reperfusion, telmisartan reversed the trend in inducible nitric oxide synthase activities and the level of myeloperoxidase. CONCLUSION(S): telmisartan is effective in reversing tissue damage induced by ischemia/reperfusion in ovaries.

The effects of methanol extract of Lobaria pulmonaria, a lichen species, on indometacin-induced gastric mucosal damage, oxidative stress and neutrophil infiltration.

Lobaria pulmonaria, a lichen species, has been used in traditional medicine for the treatment of various diseases. This study was designed to determine the gastroprotective effect of the methanol extract of L. pulmonaria in an indometacin-induced ulcer model in rats. The results showed that gastric lesions were significantly reduced in a dose-dependent manner. Furthermore, the administration of indometacin caused a significant decrease in the levels of superoxide, glutathione peroxidase and reduced glutathione and an increase in the lipid peroxidation level. Administration of the lichen extract, however, produced an increase in the levels of these enzymes and a decrease in lipid peroxidation levels, although catalase and myeloperoxidase levels were unaffected. The present results suggested that Lobaria pulmonaria has a gastroprotective effect, probably due to reducing oxidative stress and neutrophil infiltration.

Beneficial effects of vegetable oils (corn, olive and sunflower oils) and alpha-tocopherol on anti-inflammatory and gastrointestinal profiles of indomethacin in rats.

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as indomethacin are widely used in the treatment of inflammation, fever and pain. However, NSAIDs cause gastric damage as a major adverse reaction. In this study, the effects of vegetable oils (corn, olive and sunflower oils) and alpha-tocopherol on anti-inflammatory and gastrointestinal profiles of indomethacin were evaluated in rats. Results showed that indomethacin given with sunflower, corn and olive oils reduced paw edema induced by carrageenan by 79.5%, 74.0% and 60.5%, whereas individual indomethacin and diclofenac reduced paw edema by 56.2% and 50.7%, respectively. Furthermore, it has been found that the vegetable oils possess significant anti-inflammatory effect against paw edema when given alone. These results showed that the vegetable oils have beneficial effects on reduction paw edema induced by carrageenan. Besides, the administration of indomethacin together with the vegetable oils and alpha-tocopherol did not cause a statistically significant gastric damage in rats (P>0.05). However, indomethacin caused statistically significant gastric lesions as compared with untreated rats (P<0.05). Moreover, it was also found that the effects of the vegetable oils and alpha-tocopherol improved the levels of antioxidant defense systems in rat stomach tissues against oxidative damage. These results suggest that indomethacin as well as other NSAIDs do not have any adverse effect on the gastrointestinal tract when they are used together with vegetable oils and vitamin E or as the preparations of the oils.

Amiodarone has anti-inflammatory and anti-oxidative properties: an experimental study in rats with carrageenan-induced paw edema.

Amiodarone is a widely used anti-arrhythmic agent. We have investigated alterations in the glutathione (GSH) level and the activities of anti-oxidative enzymes (superoxide dismutase, catalase, glutathione s-transferase and glutathione reductase) and myeloperoxidase, as marker of acute inflammation, following oral administration of amiodarone and diclofenac in rats with carrageenan-induced paw edema. In the present study, we found that 1) Amiodarone reduced the development of carrageenan-induced paw edema, to a greater degree than diclofenac; 2) Amiodarone and diclofenac alleviated increases in the activities of catalase and glutathione s-transferase enzymes resulting from edema; 3) Amiodarone and diclofenac ameliorated depressions in the GSH level and the activities of superoxide dismutase and glutathione reductase enzymes caused by carrageenan injection; and 4) All doses of amiodarone and diclofenac caused an amplification in myeloperoxidase activity resulting from induced paw edema. These results suggest that the anti-inflammatory effect of amiodarone on carrageenan-induced acute inflammation can be attributed to its ameliorating effect on the oxidative damage.

Gastroprotective and antioxidant effects of usnic acid on indomethacin-induced gastric ulcer in rats.

Usnea longissima, a medicinal lichen of Anatolia (Turkey), is used in the treatment of gastric ulcer in local folk medicine. In this paper, the gastroprotective effect of usnic acid (UA) isolated from Usnea longissima was investigated in the indomethacin-induced gastric ulcers in rats at doses of 25, 50, 100 and 200 mg/kg body weight. The gastric lesions were significantly reduced by all doses of UA as compared with the indomethacin (25 mg/kg body weight) treated group. In the stomach tissues of treated animals, the in vivo antioxidant levels were evaluated. The administration of indomethacin caused a significant decrease in the levels of superoxide dismutase (SOD), glutathione peroxidase (GPx) and reduced glutathione (GSH), and an increase in the lipid peroxidation (LPO) level (p < 0.05). The administration of all doses of UA reversed the trend, inducing a significant increase of SOD, GSH and GPx levels and a reduction in LPO level in tissues. However, catalase (CAT), glutathione reductase (GR) and myeloperoxidase (MPx) activities, increased by indomethacin, were found to be lower in the UA- and ranitidine-treated groups. The gastric mucosal constitutive NO synthase (cNOS) and inducible NO synthase (iNOS) activities were also investigated in tissues of UA- (100 mg/kg), ranitidine- (50 mg/kg) and indomethacin-treated rat groups. The administration of UA and ranitidine increased the cNOS activity and lowered the iNOS activity as compared with indomethacin-treated group. These results suggest that the gastroprotective effect of UA can be attributed to its reducing effect on the oxidative damage and neutrophil infiltration in tissues.

Comparison of antioxidant activity and phenolic content of three lichen species.

The antioxidant activities (AA), reducing powers (RP) and total phenolic contents (TPC) of methanol and water extracts of three lichen species, Usnea longissima Ach., Usnea florida (L.) Weber ex Wigg. and Lobaria pulmonaria (L.) Hoffm. were determined in vitro. Of the extracts tested, the methanol extracts of Lobaria pulmonaria and Usnea longissima showed potent antioxidant activities. The methanol extract of L. pulmonaria also had the highest total phenolic contents (87.9 mg/g lyophylisate). For the methanol extract of this species, there was also a strong correlation between antioxidant activity and total phenolic contents. However, a similar correlation was not observed for U. longissima. Although the methanol extract of U. longissima had a lower phenolic content (38.6 mg/g lyophylisate), it exhibited potent antioxidant activity. On the other hand, there was a strong correlation between the reducing powers and the total phenolic contents of the extracts. The highest reducing power was determined for the methanol extract of L. pulmonaria.