Band 27, Heft 1

Background: Hydroxy safflor yellow A (HSYA) has been translated clinically for cardiovascular diseases. HSYA is also greatly acknowledged for its protective effects against cerebral ischemic-reperfusion (I/R) injury. Although the precise mechanism of cerebral I/R injury is not fully understood, oxygen-derived free radicals and mitochondrial permeability transition pore (mPTP) opening during I/R injury are widely recognized as an important contributor to neuronal injury. Thus, we speculated that the neuroprotective effects of HSYA against cerebral I/R injury may be associated with mPTP modulation. Methods: Induction of I/R injury was achieved by 60 min of middle cerebral artery occlusion, followed by reperfusion for 24 h. For behavior and cognitive assessment, neurological scoring (NSS), rotarod, and Y-maze task were performed. Oxidative damage was measured in terms of markers such as malondialdehyde, reduced glutathione, and catalase levels and cerebral infarct volumes were quantified using 2,3,5-triphenyl tetrazolinium chloride staining. I/R injury-induced inflammation was determined using tumor necrosis factor-α (TNF-α) levels. Results: Animals exposed to I/R injury showed neurological severity, functional and cognitive disability, elevated oxidative markers, and TNF-α levels along with large infarct volumes. HSYA treatment during onset of reperfusion ameliorated performance in NSS, rotarod and Y-maze attenuated oxidative damage, TNF-α levels, and infarction rate. However, treatment with carboxyatractyloside, an mPTP opener, 20 min before HSYA, attenuated the protective effect of HSYA. Conclusions: Our study confirmed that protective effect of HSYA may be conferred through its free radical scavenger action followed by inhibiting the opening of mPTP during reperfusion and HSYA might act as a promising therapeutic agent against cerebral I/R injury.

Background: Neuropathic pain is associated with severe chronic sensory disturbances characterized by spontaneous pain, increased responsiveness to painful stimuli (hyperalgesia) and pain perceived in response to non-noxious stimuli (allodynia). Morphine is effective treatment for neuropathic pain but produces tolerance on chronic use. The present study was designed to explore the anti-nociceptive and anti-hyperalgesic effect of grape seed extract using sciatic nerve ligation-induced neuropathic pain in rats. Methods: Chronic constructive injury (CCI) was performed under anesthesia, on one side leg exposed by making a skin incision, and chromic gut ligatures were tied loosely around the sciatic nerve at 1 mm intervals. The treatment with grape seed proanthocyanidin extract (GSPE) (100 and 200 mg/kg, p.o.) was initiated on 7th day post-surgery and continued for next 14 days. Morphine (10 mg/kg, s.c.) alone and morphine in combination with GSPE (100 mg/kg, p.o.) were administered in CCI rats for 5 days starting from 7th day. On 3rd, 7th, 14th and 21st day, behavioral parameters (mechanical allodynia and thermal hyperalgesia) were assessed. Then the animals were killed on 22nd day and biochemical parameters [reduced glutathione (GSH), lipid peroxidation (LPO), catalase, nitrite, superoxide dismutase (SOD)] were assessed. Results: Ligation of the sciatic nerve significantly induced mechanical allodynia and thermal hyperalgesia and induces oxidative stress (increase in LPO and nitrite) and decline of anti-oxidant enzyme levels (catalase, SOD, GSH) in sciatic nerve homogenate. GSPE (100 and 200 mg/kg, p.o.) attenuated all the behavioural and biochemical parameters. Morphine also significantly reversed the symptoms of neuropathic pain but produced tolerance after 5 days. Further, co-treatment of GSPE (100 mg/kg) with morphine (10 mg/kg, s.c.) in CCI rats significantly reversed the morphine tolerance and enhanced its anti-hyperalgesic effect as compared to the morphine-alone-treated group. Conclusions: In the present set of experiments, GSPE showed a significant anti-hyperalgesic and anti-nociceptive effect in rats.

Background: Nicotine is one of the psychostimulant agents displaying parasympathomimetic activity; the chronic neurochemical and behavioral effects of nicotine remain unclear. Exercise lowers stress and anxiety and can act as a non-pharmacologic neuroprotective agent. In this study, the protective effects of exercise in nicotine withdrawal syndrome-induced anxiety, depression, and cognition impairment were investigated. Methods: Seventy adult male rats were divided randomly into five groups. Group 1 served as negative control and received normal saline (0.2 mL/rat, i.p.) for 30 days, whereas group 2 (as positive control) received nicotine (6 mg/kg/day, s.c.) for the first 15 days. Groups 4, 5, and 6 were treated with nicotine (6 mg/kg/day, s.c.) for the first 15 days and then were treated with forced exercise, bupropion (20 mg/kg/day, i.p.), or a combination of the two for the following 15 days. Between day 25 and day 30, Morris water maze was used to evaluate spatial learning and memory. From days 31 to 35, the elevated plus maze (EPM), open field test (OFT), forced swim test (FST), and tail suspension test (TST) were used to investigate the level of anxiety and depression in the subjects. Results: Nicotine-dependent animals indicated a reflective depression and anxiety in a dose-dependent manner in FST, EPM, and TST, which were significantly different from the control group and also can significantly attenuate the motor activity and anxiety in OFT. Conclusions: Forced exercise, bupropion, or their combination can attenuate nicotine cessation-induced anxiety, depression, and motor activity in the mentioned behavioral assay. We conclude that forced exercise can protect the brain against nicotine withdrawal-induced anxiety, depression, and cognitive alteration.

Background: Aspartame (N-L-α-aspartyl-L-phenylalanine-1-methyl ester) (ASP) is a synthetic sweetener used in foods and its safety remains controversial. The study was designed to investigate the effects of long-term administration of aspartame on redox status, lipid profile and biochemical indices in tissues of male Wistar rats. Methods: Rats were assigned into four groups and given distilled water (control), aspartame at doses of 15 mg/kg (ASP 1), 35 mg/kg (ASP 2) and 70 mg/kg (ASP 3) daily by oral gavage for consecutive 9 weeks. Results: Administration of ASP 2 and ASP 3 significantly increased the weight of liver and brain, and relative weight of liver of rats. Lipid peroxidation products significantly increased in the kidney, liver and brain of rats at all doses of ASP with concomitant depletion of antioxidant parameters, viz. glutathione-s-transferase, glutathione peroxidase, superoxide dismutase, catalase and reduced glutathione. Furthermore, ASP 2 and ASP 3 significantly increased the levels of gamma glutamyl transferase by 70% and 85%; alanine aminotransferase by 66% and 117%; aspartate aminotransferase by 21% and 48%; urea by 72% and 58% and conjugated bilirubin by 63% and 64%, respectively. Also, ASP 2 and ASP 3 significantly increased the levels of total cholesterol, triglycerides and low-density lipoprotein cholesterol in the rats. Histological findings showed that ASP 2 and ASP 3 caused cyto-architectural changes such as degeneration, monocytes infiltration and necrotic lesions in brain, kidney and liver of rats. Conclusions: Aspartame may induce redox and lipid imbalance in rats via mechanism that involves oxidative stress and depletion of glutathione-dependent system.

Background: Dietary fenugreek seeds ( Trigonella foenum - graecum ) and garlic ( Allium sativum ) have been previously observed to have cardioprotective influence in experimentally induced myocardial infarction in rats. Since low-density lipoprotein (LDL) oxidation is a key factor in the arteriosclerotic process, we evaluated their potential in minimizing the LDL oxidation in rats. Methods: Fenugreek seeds, garlic, and their combination were included along with a high-cholesterol diet for 8 weeks. Results: Iron-induced oxidation of LDL in vivo was considerably lowered by dietary fenugreek and garlic. The extent of copper-induced oxidation of isolated LDL in vitro was also significantly lesser in fenugreek-fed or fenugreek+garlic-fed rats. Anodic electrophoretic mobility of the oxidized LDL on agarose gel in case of spice-fed animals was decreased and hence consistent with the observed protective influence on LDL oxidation. Dietary fenugreek, garlic, and their combination significantly lowered lipid peroxide levels in plasma, liver, and heart in iron (II)-administered rats. The results suggest that these two dietary spices have protective effect on LDL oxidation under normal situation as well as in hypercholesterolemic situation. The protective effect of the combination of dietary fenugreek and garlic on LDL oxidation both in vivo and in vitro was greater than that of the individual spices. Conclusions: The protective effect of dietary fenugreek and garlic on LDL oxidation both in vivo and in vitro as evidenced in the present study is suggestive of their cardioprotective potential since LDL oxidation is a key factor in the arteriosclerotic process.

Background: Hattaraki pallye or prickly lettuce ( Lactuca scariola Linn.) is one among several green leafy plants that grow in north Karnataka; it is usually consumed by the people of this region and is found to be antidiabetic in nature. The objective of this study is to evaluate hypoglycemic activities of supplementation with aqueous extract of prickly lettuce ( L. scariola ) leaves in vivo in acute and subchronic exposure with or without nickel (II) along with its glucose reduction capabilities with or without nickel (II) at pH 7.0 and 9.0 in vitro. Methods: Percentage glucose reduction (in vitro) was determined by glucose oxidase-peroxidase enzymatic method at pH 7.0 and pH 9.0 using UV-Vis spectrophotometer. Hypoglycemic activities of L. scariola were carried out in alloxan-induced male diabetic rats at both acute and subchronic exposure. Results: The results showed a significant alteration in the λ max value of Ni (II) in combination with L. scariola leaves extracts at both pH 7.0 and 9.0. The aqueous extract also produced a significant reduction in the glucose concentration at pH 7.0 and pH 9.0 even in presence of Ni (II) in vitro. Lactuca scariola leaves in either acute or subchronic supplementation showed a greater glucose tolerance and hypoglycemic regulation of blood sugar in diabetic rats with or without nickel (II) treatments. Conclusions: Lactuca scariola leaves can be a substitute for synthetic drugs to treat diabetic patients.

Background: The present study evaluates the possible mechanism of sildenafil citrate (SIL) for the attenuation of renal failure in diabetic nephropathic (DN) animals. Methods: Diabetic nephropathy was induced by a single dose of streptozotocin (STZ) (60 mg/kg, i.p.) and confirmed by assessing the blood and urine biochemical parameters on the 28th day of its induction. The selected DN animals were treated with glimepiride (0.5 mg/kg, p.o.) and SIL (2.5 mg/kg, p.o.) for a period of 6 weeks. Biochemical parameters in blood and urine were estimated after the 29th and 70th day of the protocol for the estimation of the effect of SIL. Result: There were significant alterations in the blood and urine biochemical parameters in STZ-treated groups which confirmed DN. There was a significant decrease in the triglyceride level in the SIL-only-treated group on the 70th day of the protocol. The histopathology study also suggested that SIL treatment results in the improvement in the podocyte count in DN animals. Conclusions: The present study concludes that SIL improves the renal function by decreasing the triglyceride level and improving the podocyte count in DN animals.

Background: The objective of this study was to investigate the antinociceptive, anti-inflammatory, thrombolytic and hepatoprotective activities of root extracts of Premna esculenta (family: Verbenaceae). Methods: The analgesic activity was evaluated using the acetic-acid-induced writhing test in mice and radiant heat tail-flick method in rats. The anti-inflammatory activity was investigated by carrageenan-induced rat’s paw edema, while the thrombolytic activity was evaluated by in vitro clot lysis model. The hepatoprotective activity was investigated against carbon-tetrachloride-induced liver damage in rats. Results: In acetic-acid-induced writhing test, chloroform and ethyl acetate fraction of ethanolic extract at a dose of 200 mg/kg showed a significant (p<0.001) reduction in the number of writhes with 85.96% and 61.98% of inhibition, respectively. In radiant heat tail-flick method, the ethanolic extract produced 88.49% (p<0.001) elongation of tail-flicking time at 90 min after oral administration at same dose level. In the carrageenan-induced edema test, the ethanolic extract at a dose of 200 mg/kg showed a significant inhibition of paw edema with 22.68% and 17.24% inhibition after the first and third hours of the study period, respectively. In clot lysis model, the ethanolic extract at 5 mg/mL induced a significant clot lysis activity (37.69%, p<0.001). Oral administration of ethanolic extract at the dose of 400 mg/kg/day for 7 days significantly (p<0.001) reduced the elevated levels of serum glutamic pyruvic transaminase, serum glutamyl oxaloacetate transaminase and alkaline phosphatase compared to the CCl 4 -treated control group. Conclusions: The results of the study demonstrated the antinociceptive, anti-inflammatory, thrombolytic and hepatoprotective activities of roots of P. esculenta .

Background : Rheumatoid arthritis (RA) is a systemic autoimmune disorder characterized by polyarticular symmetrical arthritis. The prevalence of RA is consistent worldwide, affecting about 0.5%–1.0% of the population. The aim of this study was to investigate whether Saussurea lappa (costus) could ameliorate adjuvant arthritis (AA) in the rat for 21 days. Methods: Animals were divided into eight groups (n=5/group). Group 1 acted as control, group 2 presented the AA rats (positive control), and groups 3, 4, and 5 were treated with different doses of S. lappa (200, 400, and 600 mg/kg, respectively), whereas groups 6, 7, and 8 were AA rats and orally administered with S . lappa (200, 400, and 600 mg/kg, respectively). The changes caused by chronic inflammation were evaluated through the measurement of ankle circumference (AC). Serum C-reactive protein (CRP), interleukins (IL-1β and IL-6), tumor necrosis factor α (TNF-α), total oxidative capacity (TOC), and total antioxidant capacity (TAC) were determined. Results: Saussurea lappa dose-dependently alleviated the severity of the disease based on the reduction in AC and on the clinical scores of the histological study. Histopathological examination proved that S. lappa decreased the infiltration of inflammatory cells and synovial hyperplasia as well as protected joint destruction. Saussurea lappa reduced the serum levels of CRP, TNF-α, IL-1β, and IL-6, reduced the TOC, and improved the TAC as compared with AA rats. Conclusions: The S. lappa extract has potentially useful anti-arthritic activity as well as improves the immune and antioxidant responses of adjuvant-induced monoarthritis in rats.

Background: Exposure to radio-frequency energy (RFE) of millimeter wavelengths results in a relatively high skin-heating rate, with only a moderate rate of core heating. Yet, prolonged RFE exposure eventuates in severe hypotension and death. In this study, we characterized pathophysiological changes associated with prolonged RFE sufficient to induce hypotension. Methods: Anesthetized rats were exposed to 35-GHz RFE with a power density of 75 mW/cm 2 . Cardiovascular and temperature parameters were continuously recorded. Blood factors and histopathology were compared between sham (n=6) and exposed (n=12) animals. Results and conclusions: Using infrared thermography, we confirmed a relatively high temperature (>46 °C) at the skin surface of the irradiated site. Histopathological results included hemorrhage and congestion of blood vessels in the dermis and subcutis of irradiated skin without induction of burn. As in environmental heating, significantly greater levels of serum glucose, creatinine, uric acid, and anion gap were observed in rats exposed to longer-duration RFE (approx. 38-min exposures) than in shorter-duration (approx. 19-min exposures) or sham (time control) animals. However, changes in blood electrolytes or liver enzymes (often seen during heatstroke) were not observed after the RFE exposures. Even without major tissue injury or serum/plasma enzyme and electrolyte changes, rapid cutaneous heating via RFE induced profound hypotension that eventuated in death.