Effects of Berberis vulgaris fruit extract on oxidative stress status in the kidney and liver of diabetic rats.

OBJECTIVES: Oxidative stress has a key role in the diabetes pathogenesis and complications. Berberis vulgaris is known in folk medicine for curing several diseases. The current research aimed to assess the influences of Berberis vulgaris fruit extract against oxidative stress in streptozotocin-induced diabetic rats. METHODS: Streptozotocin (60 mg/kg, ip) was injected to male rats. After diabetes confirmation, animals received the Berberis vulgaris fruit extract daily at amounts of 3.5 and 7.5 % of drinking water (v/v) for six weeks. Total thiol and lipid peroxidation levels were assessed in the serum, liver, kidney and spleen at the end of the study. RESULTS: Diabetic rats exhibited hyperglycemia along with enhancement of lipid peroxidation levels in the serum, liver, kidney and spleen, and decrement of total thiol content in the kidney and liver tissues. Chronic administration of Berberis vulgaris fruit extract at amount of 3.5 % of drinking water decreased the lipid peroxidation level in the serum and liver, and enhanced total thiol level in the liver and kidney. CONCLUSIONS: Berberis vulgaris fruit extract exerts antioxidant activity in the serum, liver and kidney organs of diabetic rats. Therefore, it might be used in the prevention and control of diabetes complications.

Neuroprotective effects of sesamol against LPS-induced spatial learning and memory deficits are mediated via anti-inflammatory and antioxidant activities in the rat brain.

Objective: Sesamol is a phenolic lignan extracted from sesame seeds, and it possesses anti-inflammatory and antioxidant activities. Lipopolysaccharide (LPS) is known to produce neuroinflammatory responses and memory impairment. The current study aimed to investigate the protective influence of sesamol against LPS-mediated neuroinflammation and memory impairment. Materials and Methods: Sesamol (10 and 50 mg/kg) was injected to Wistar rats for two weeks. Then, animals received LPS injection (1 mg/kg) for five days, while treatment with sesamol was performed 30 min before LPS injection. Spatial learning and memory were assessed by the Morris water maze (MWM), two hours after LPS injection on days 15-19. Biochemical assessments were performed after the end of behavioral experiments. Results: LPS-administered rats showed spatial learning and memory deficits, since they spent more time in the MWM to find the hidden platform and less time in the target quadrant. Besides these behavioral changes, tumor necrosis factor-α (TNF-α) and lipid peroxidation levels were increased, while total thiol level was decreased in the hippocampus and/or cerebral cortex. In addition, sesamol treatment (50 mg/kg) for three weeks decreased the escape latency and increased the time on probe trial. Sesamol also reduced lipid peroxidation and TNF-α level, while enhanced total thiol level in the brain of LPS-exposed rats. Conclusion: Supplementation of sesamol attenuated learning and memory impairments in LPS-treated rats via antioxidative and anti-inflammatory activities in the rat brain.

Treadmill running and Levisticum Officinale extract protect against LPS-induced memory deficits by modulating neurogenesis, neuroinflammation and oxidative stress.

Neuroinflammation plays an essential role in the pathogenesis of Alzheimer's disease. The preventive effect of physical exercise on attenuating neuroinflammation has not been completely defined. Levisticum officinale is known as a medicinal plant with antioxidant and anti-inflammatory properties. The current study was designed to investigate the neuroprotective impacts of treadmill running and Levisticum officinale on lipopolysaccharide (LPS)-induced learning and memory impairments and neuroinflammation in rats. Male Wistar rats ran on a treadmill and/or were pretreated with Levisticum officinale extract at a dose of 100 mg/kg for a week. Then, rats received intraperitoneal injection of LPS at a dose of 1 mg/kg. Treadmill running and/or treatment of extract lasted three more weeks. Behavioral, molecular, biochemical and immunohistochemical assessments were carried out after the end of the experiment. LPS administration resulted in spatial learning and memory impairments along with increased mRNA expression of interleukin-6 and malondialdehyde levels, as well as decreased superoxide dismutase activity and neurogenesis in the hippocampus. Moreover, treadmill running for four weeks, alone and in combination with Levisticum officinale extract attenuated spatial learning and memory deficits, decreased the mRNA expression of interleukin-6 and malondialdehyde levels, and enhanced superoxide dismutase activity and neurogenesis in the hippocampus. In conclusion, the advantageous effects of running exercise and Levisticum officinale extract on LPS-induced memory impairments are possibly due to the antioxidant and anti-inflammatory activity and enhancing neurogenesis.

Supplementation of Carvacrol Attenuates Hippocampal Tumor Necrosis Factor-Alpha Level, Oxidative Stress, and Learning and Memory Dysfunction in Lipopolysaccharide-Exposed Rats.

Background: Carvacrol is a natural phenolic monoterpene with anti-inflammatory and antioxidant bioactivities. Neuroinflammatory and oxidative stress responses play a crucial role in the pathogenesis of Alzheimer's disease. The present study examined the effect of carvacrol on brain tumor necrosis factor-alpha (TNF-α) level and oxidative stress as well as spatial learning and memory performances in lipopolysaccharide (LPS)-exposed rats. Materials and Methods: The rats were treated with either carvacrol (25 and 50 mg/kg) or Tween 80 for 2 weeks. Thereafter, LPS (1 mg/kg) or saline was intraperitoneally administered on days 15-19, 2 h before Morris water maze task, and treatments with carvacrol or Tween 80 were performed 30 min prior to behavioral testing. The level of TNF-α, lipid peroxidation, and total thiol concentration were measured in the hippocampus and cerebral cortex at the end of the experiment. Results: It was found that LPS-exposed rats exhibited spatial learning and memory dysfunction, which was accompanied by increased TNF-α level and lipid peroxidation, and decreased total thiol concentration in the hippocampus and/or cortex. Moreover, treatment with carvacrol at a dose of 25 mg/kg attenuated learning and memory impairments, decreased TNF-α and lipid peroxidation level in the hippocampus and cortex, and increased total thiol concentration in the cortex. Conclusion: Carvacrol exerts neuroprotective effects against LPS-induced spatial memory deficits through attenuating hippocampal TNF-α level and oxidative stress in rats.

Effects of crocin on spatial or aversive learning and memory impairments induced by lipopolysaccharide in rats.

OBJECTIVE: Neuroinflammation and oxidative stress play essential roles in the pathogenesis and progression of neurodegenerative diseases, such as Alzheimer's disease. Crocin, main active constituent of Crocus sativus L. (saffron), possesses anti-inflammatory, anti-apoptotic and anti-oxidative capacity. The aim of the present study was to investigate the neuroprotective effect of crocin on lipopolysaccharide (LPS)-induced learning and memory deficits and neuroinflammation in rats. MATERIALS AND METHODS: The animals were randomly classified into four groups, including control, LPS, crocin 50 and crocin 100. The rats were treated with either crocin (50 and 100 mg/kg) or saline for a week. Later, LPS (1 mg/kg, i.p.) or saline was administered, and treatments with crocin or saline were continued for 3 more weeks. The behavioral tasks for spatial and aversive memories were performed by the Morris water maze and passive avoidance tasks from post-injection days 18 to 24. Furthermore, the levels of interleukine-1ß, lipid peroxidation and total thiol were assayed in the hippocampus and cerebral cortex. RESULTS: Our results demonstrated that treatment of LPS-treated rats with crocin decreased the escape latency in the Morris water maze and increased the time spent in the target quadrant in the probe trial. Moreover, crocin increased step-through latency in the passive avoidance test. However, there was no significant difference in the oxidative and neuroinflammatory responses among the experimental groups. CONCLUSION: Pretreatment with crocin attenuates spatial or aversive learning and memory deficits in LPS-treated rats.

The effects of concurrent treatment of silymarin and lactulose on memory changes in cirrhotic male rats.

Introduction: Chronic liver disease frequently accompanied by hepatic encephalopathy (HE). Changes in the permeability of the blood-brain barrier in HE, make an easier entrance of ammonia among other substances to the brain, which leads to neurotransmitter disturbances. Lactulose (LAC), causes better defecation and makes ammonia outreach of blood. Silymarin (SM) is a known standard drug for liver illnesses. The purpose of this research was to determine the results of LAC and SM combined treatment, on the changes in memory of cirrhotic male rats. Methods: The cirrhotic model established by treatment with thioacetamide (TAA) for 18 weeks. Cirrhotic rats randomized to four groups (n = 7): TAA group (received drinking water), LAC group (2 g/kg/d LAC in drinking water), SM group (50 mg/kg/d SM by food), SM+ LAC group (similar combined doses of both compounds) for 8 weeks. The control group received drinking water. The behavior examined by wire hanging (WH), passive avoidance (PA), and open field (OF) tests. Results: Our findings showed that treatment with SM+LAC effectively increased PA latency, compared with the control group. The results showed that the administration of LAC and SM+LAC affected the number of lines crossed, the total distance moved and velocity in the OF tests. Conclusion: SM and LAC have anti-inflammatory effects that are memory changing. It may be due to their useful effects. These results indicated that SM+LAC restored memory disturbance and irritated mood in the cirrhotic rats. Comparable neuroprotection was never previously informed. Such outcomes are extremely promising and indicate the further study of SM+LAC.

Neuroprotective effects of Levisticum officinale on LPS-induced spatial learning and memory impairments through neurotrophic, anti-inflammatory, and antioxidant properties.

Levisticum officinale (Apiaceae) has been identified as a medicinal plant in traditional medicine, with the anti-inflammatory, antioxidant, and anticholinesterase activities. The present study aims to evaluate the effects of Levisticum officinale extract (LOE) on lipopolysaccharide (LPS)-induced learning and memory deficits and to examine its potential mechanisms. LOE was administered to adult male Wistar rats at doses of 100, 200, and 400 mg kg-1 for a week. Later, LPS was intraperitoneally injected at a dose of 1 mg kg-1 to induce neuroinflammation, and treatment with LOE continued for 3 more weeks. Behavioral, biochemical, and molecular analyses were performed at the end of the experiment. Moreover, quantitative immunohistochemical assessments of the expression of Ki-67 (intracellular proliferation marker) in the hippocampus were performed. The results revealed that LPS injection caused spatial memory impairment in the rats. Daily LOE treatment at applied doses for 4 weeks attenuated spatial learning and memory deficits in LPS-injected rats. Furthermore, LPS significantly increased the mRNA expression level of interleukin-6 in the hippocampus, which was accompanied by decreased brain-derived neurotrophic factor (BDNF) mRNA expression levels. Moreover, LPS increased the levels of malondialdehyde, reduced the antioxidant enzyme activities of catalase and superoxide dismutase in the hippocampus, and impaired neurogenesis. However, pre-treatment with LOE at a dose of 100 mg kg-1 significantly reversed the LPS-induced changes, and improved neurogenesis. In conclusion, the beneficial effect of LOE on the improvement of learning and memory could be attributed to its anti-inflammatory and antioxidant activities, along with its ability to increase BDNF expression and neurogenesis in the hippocampus.

Effects of carvacrol and physical exercise on motor and memory impairments associated with Parkinson's disease.

The present study was undertaken to investigate the effects of carvacrol and treadmill exercise on memory deficit, rotational behavior and oxidative stress biomarkers in a 6-OHDA-lesioned rat model of Parkinson's disease. Wistar rats were treated with carvacrol at a dose of 25 mg/kg and/or ran on a treadmill for a week. Then, 6-OHDA was microinjected into the medial forebrain bundle and treatments continued for six more weeks. Aversive memory, rotational behavior and oxidative stress biomarkers were assessed at the end of week six. The 6-OHDA-lesioned group showed a significant increase in rotational behavior and a decrease in step-through latency in the passive avoidance test compared with the sham group. These behaviors were accompanied by increased lipid peroxidation levels and decreased total thiol concentration in the striatum and/or hippocampus of the hemiparkinsonian rats. Moreover, treatment with carvacrol and exercise reduced rotational behavior and improved aversive memory deficit, which was accompanied by decreased lipid peroxidation levels and increased total thiol concentration in the striatum and/or hippocampus. In conclusion, treatment with carvacrol and treadmill exercise ameliorated motor and memory deficits by modulating oxidative stress in the striatum and hippocampus of hemiparkinsonian rats. Therefore, the combination of carvacrol and treadmill exercise could be an effective therapeutic tool for treatment of neurobehavioral deficits in Parkinson's disease patients.

Effects of carvacrol and physical exercise on motor and memory impairments associated with Parkinson's disease / Efeitos do carvacrol e do exercício físico sobre o comprometimento motor e de memória associados à doença de Parkinson

ABSTRACT The present study was undertaken to investigate the effects of carvacrol and treadmill exercise on memory deficit, rotational behavior and oxidative stress biomarkers in a 6-OHDA-lesioned rat model of Parkinson's disease. Wistar rats were treated with carvacrol at a dose of 25 mg/kg and/or ran on a treadmill for a week. Then, 6-OHDA was microinjected into the medial forebrain bundle and treatments continued for six more weeks. Aversive memory, rotational behavior and oxidative stress biomarkers were assessed at the end of week six. The 6-OHDA-lesioned group showed a significant increase in rotational behavior and a decrease in step-through latency in the passive avoidance test compared with the sham group. These behaviors were accompanied by increased lipid peroxidation levels and decreased total thiol concentration in the striatum and/or hippocampus of the hemiparkinsonian rats. Moreover, treatment with carvacrol and exercise reduced rotational behavior and improved aversive memory deficit, which was accompanied by decreased lipid peroxidation levels and increased total thiol concentration in the striatum and/or hippocampus. In conclusion, treatment with carvacrol and treadmill exercise ameliorated motor and memory deficits by modulating oxidative stress in the striatum and hippocampus of hemiparkinsonian rats. Therefore, the combination of carvacrol and treadmill exercise could be an effective therapeutic tool for treatment of neurobehavioral deficits in Parkinson's disease patients.

RESUMO O presente estudo foi realizado para investigar os efeitos do carvacrol e do exercício em esteira sobre o déficit de memória, comportamento rotacional e biomarcadores de estresse oxidativo em um modelo animal (ratos lesionados por 6-OHDA) da doença de Parkinson (DP). Ratos Wistar foram tratados com carvacrol na dose de 25 mg/kg e/ou correram em uma esteira por uma semana. Depois, 6-OHDA foi microinjetada no feixe do prosencéfalo medial e os tratamentos continuaram por mais seis semanas. A memória aversiva, o comportamento rotacional e biomarcadores de estresse oxidativo foram avaliados no final da semana 6. O grupo 6-OHDA mostrou um aumento significativo no comportamento rotacional e uma diminuição na latência no teste de esquiva passiva em comparação com o grupo "sham". Estes comportamentos foram acompanhados por aumento dos níveis de peroxidação lipídica e diminuição da concentração total de tiol no estriado e/ou hipocampo de ratos hemiparkinsonianos. Além disso, o tratamento com carvacrol e exercício reduziu o comportamento rotacional e melhorou o déficit de memória aversiva, que foi acompanhado pela diminuição dos níveis de peroxidação lipídica e aumento da concentração total de tiol no estriado e/ou hipocampo. Em conclusão, o tratamento com carvacrol e exercícios em esteira melhorou os déficits motor e de memória, modulando o estresse oxidativo no estriado e no hipocampo de ratos hemiparkinsonianos. Portanto, a combinação de carvacrol e exercício em esteira pode ser uma ferramenta terapêutica eficaz para o tratamento de déficits neurocomportamentais em pacientes com DP.

Effects of Boswellia serrata resin extract on motor dysfunction and brain oxidative stress in an experimental model of Parkinson's disease.

OBJECTIVE: Boswellia serrata oleo-gum resin (frankincense) exerted antioxidant and anti-inflammatory effects against several diseases, such as; asthma, rheumatoid arthritis and irritable bowel syndrome. In the current study, the influences of B. serrata resin extract on motor dysfunction and oxidative stress markers were investigated in the intrastriatal 6-hydroxydopamine (6-OHDA) model of Parkinson's disease (PD). MATERIALS AND METHODS: The animals were randomly assigned to sham, lesion (6-OHDA), and three lesion groups treated with ethyl alcoholic extract of B. serrata at doses of 125, 250 and 500 mg/kg for 3 weeks. The neurotoxin 6-OHDA (12.5 µg) was microinjected into the left striatum to induce PD in male rats. Motor behavior was assessed by rotational and elevated narrow beam tests. Oxidative stress markers were measured in striatal and midbrain homogenates. RESULTS: There was a significant increase in contralateral rotations in 6-OHDA group versus sham group (p<0.001), and treatment with B. serrata resin extract at doses of 125 and 250 mg/kg significantly decreased the rotations in comparison to 6-OHDA group (p<0.001 and p<0.001, respectively). The 6-OHDA group also showed considerable elevation in the latency to initiate crossing (p<0.001) and the total time (p<0.001) on narrow beam test. Moreover, treatment with B. serrata extract at doses of 125, 250 and 500 mg/kg caused a significant reduction in the latency and total time (p<0.001, p<0.001, and p<0.01, respectively). Biochemical analysis showed no significant difference in oxidative stress markers levels among the groups. CONCLUSION: Our findings suggest that B. serrata resin extract acts as an anti-inflammatory and antioxidant agent that protects nigrostriatal dopaminergic neurons and improve motor impairments in PD.

Pretreatment with crocin along with treadmill exercise ameliorates motor and memory deficits in hemiparkinsonian rats by anti-inflammatory and antioxidant mechanisms.

The motor symptoms of Parkinson's disease (PD) are preceded by non-motorized symptoms including memory deficits. Treatment with dopamine replacement medications, such as L-DOPA only control motor symptoms and does not meet the clinical challenges of the disease, such as dyskinesia, non-motor symptoms, and neuroprotection. The purpose of the current study was to examine the neuroprotective potential of crocin and physical exercise in an animal model of PD. Male Wistar rats ran on a horizontal treadmill and/or pretreated with crocin at a dose of 100 mg/kg. Then, 16 µg of the neurotoxin 6-hydroxydopamine (6-OHDA) was microinjected into left medial forebrain bundle. Crocin treatment and/or exercise continued for 6 more weeks. Spatial and aversive memories, rotational behaviour, inflammatory and oxidative stress parameters were assessed at the end of week 6 post surgery. The results showed that pretreatment with crocin alone and in combination with exercise decreased the total number of rotaions as compared with 6-OHDA-lesioned group. Furthermore, treatment of parkinsonian rats with crocin along with exercise training improved aversive and spatial memories. Biochemical analysis showed that crocin and exercise (alone and in combination) reduced tumor necrosis factor- (TNF) α levels in the striatum. Moreover, treatment with crocin at a dose of 100 mg/kg decreased the lipid peroxidation levels in the hippocampus, while exercise training increased the total thiol concentration. In conclusion, our findings indicated that pretreatment with crocin along with treadmill exercise ameliorated motor and memory deficits induced by 6-OHDA, which is considered to be due to their antioxidant and anti-inflammatory activities. The results suggest that combined therapy with crocin and exercise may be protective for motor and memory deficits in PD patients.

Chronic treatment with carvacrol improves passive avoidance memory in a rat model of Parkinson's disease.

The present study investigated the effects of carvacrol on motor and memory deficits as well as hyperalgesia in the 6-OHDA-lesioned rat model of Parkinson's disease. The animals were subjected to unilateral microinjection of 6-OHDA into the medial forebrain bundle and treated with carvacrol (25, 50 and 100 mg/kg, ip) for six weeks after surgery. The 6-OHDA-lesioned rats showed contralateral rotations towards the lesion side, which was accompanied by learning and memory deficits in a passive avoidance test and a decrease in tail withdrawal latency in a tail flick test at the end of week 6. The results also showed that treatment with carvacrol at a dose of 25 mg/kg ameliorated memory deficits, with no effect on rotations and hyperalgesia in lesioned rats. In conclusion, carvacrol improves memory impairments in rats with Parkinson's disease; therefore, it may serve as an adjunct therapy for the alleviation of memory deficits in Parkinson's disease patients.

Chronic treatment with carvacrol improves passive avoidance memory in a rat model of Parkinson's disease / O tratamento com carvacrol melhora a memória de esquiva passiva em um modelo da doença de Parkinson em ratos

ABSTRACT The present study investigated the effects of carvacrol on motor and memory deficits as well as hyperalgesia in the 6-OHDA-lesioned rat model of Parkinson's disease. The animals were subjected to unilateral microinjection of 6-OHDA into the medial forebrain bundle and treated with carvacrol (25, 50 and 100 mg/kg, ip) for six weeks after surgery. The 6-OHDA-lesioned rats showed contralateral rotations towards the lesion side, which was accompanied by learning and memory deficits in a passive avoidance test and a decrease in tail withdrawal latency in a tail flick test at the end of week 6. The results also showed that treatment with carvacrol at a dose of 25 mg/kg ameliorated memory deficits, with no effect on rotations and hyperalgesia in lesioned rats. In conclusion, carvacrol improves memory impairments in rats with Parkinson's disease; therefore, it may serve as an adjunct therapy for the alleviation of memory deficits in Parkinson's disease patients.

RESUMO O presente estudo investigou os efeitos do carvacrol nos déficits motores e de memória, bem como na hiperalgesia, em um modelo da doença de Parkinson (DP) em ratos com lesões 6-OHDA. Os animais foram submetidos a microinjeção unilateral de 6-OHDA no feixe mediano do prosencéfalo e tratados com carvacrol (25, 50 e 100 mg / kg, ip) durante 6 semanas após a cirurgia. Os ratos com lesões 6-OHDA mostraram rotações contralaterais para o lado da lesão, que foram acompanhadas de déficits de aprendizagem e de memória em um teste de evitação passiva, e de uma diminuição da latência de retirada da cauda em um teste de cauda no final da semana 6. Os resultados também mostraram que o tratamento crônico com carvacrol a uma dose de 25 mg / kg aliviou os déficits de memória, sem efeito sobre rotações e hiperalgesia em ratos lesados. Em conclusão, o carvacrol melhora a deficiência de memória em ratos com DP e, portanto, pode servir como uma terapia complementar para aliviar os déficits de memória em pacientes com DP.

Effect of intra-hippocampal injection of human recombinant growth hormone on synaptic plasticity in the nucleus basalis magnocellularis-lesioned aged rats.

In this study, we proposed that administration of hippocampal growth hormone in ageing animals with growth hormone deficiency can compensate long-term potentiation and synaptic plasticity in nucleus basalis magnocellularis (NBM)-lesioned rats. Aged male Wistar rats were randomly divided into six groups (seven in each) of sham-operated healthy rats (Cont); NBM-lesioned rats (L); NBM-lesioned rats and intrahippocampal injection of growth hormone vehicle (L + Veh); NBM-lesioned and intrahippocampal injection of growth hormone (10, 20 and 40 µg.2 µl-1) (L + GH). In vivo electrophysiological recording techniques were used to characterize maintenance of long-term potentiation at distinct times (1, 2, 3, 24 and 48 hours) after high-frequency stimulation. The population spike was enhanced significantly for about 48 hours following tetanic stimulation in rats treated with a dose-dependent growth hormone compared to the vehicle group (p < 0.05), possibly through neuronal plasticity and neurogenesis in affected areas.

Effect of intra-hippocampal injection of human recombinant growth hormone on synaptic plasticity in the nucleus basalis magnocellularis-lesioned aged rats / Efeito da injeção intrahipocampal de hormônio do crescimento humano recombinante sobre a plasticidade sináptica em ratos envelhecidos lesados do núcleo basalis magnocellularis

ABSTRACT In this study, we proposed that administration of hippocampal growth hormone in ageing animals with growth hormone deficiency can compensate long-term potentiation and synaptic plasticity in nucleus basalis magnocellularis (NBM)-lesioned rats. Aged male Wistar rats were randomly divided into six groups (seven in each) of sham-operated healthy rats (Cont); NBM-lesioned rats (L); NBM-lesioned rats and intrahippocampal injection of growth hormone vehicle (L + Veh); NBM-lesioned and intrahippocampal injection of growth hormone (10, 20 and 40 µg.2 µl-1) (L + GH). In vivo electrophysiological recording techniques were used to characterize maintenance of long-term potentiation at distinct times (1, 2, 3, 24 and 48 hours) after high-frequency stimulation. The population spike was enhanced significantly for about 48 hours following tetanic stimulation in rats treated with a dose-dependent growth hormone compared to the vehicle group (p < 0.05), possibly through neuronal plasticity and neurogenesis in affected areas.

RESUMO Neste estudo, propusemos que a administração de hormônio hipocampal do crescimento em animais envelhecidos com deficiência de hormônio do crescimento pode compensar a potencialização em longo prazo e a plasticidade sináptica em ratos lesados do núcleo basalis magnocellularis (NBM). Ratos machos Wistar foram divididos aleatoriamente em seis grupos (sete ratos em cada grupo) de ratos falso-operados saudáveis (Cont); ratos lesados do NBM (L); ratos lesados do NBM e injeção intrahipocampal de veículo de hormônio do crescimento (L + Veh); ratos lesados do NBM e injeção de hormônio do crescimento (10, 20 e 40 μg.2 μl-1) (L + GH). Técnicas de registro eletrofisiológico in vivo foram utilizadas para caracterizar a manutenção da potencialização em longo prazo em momentos distintos (1, 2, 3, 24 e 48 horas) após estimulação de alta frequência. O pico populacional aumentou significativamente cerca de 48 horas após a estimulação tetânica em ratos tratados com um hormônio do crescimento dose-dependente, em comparação com o grupo veículo (p <0,05), possivelmente através da plasticidade neuronal e da neogênese nas áreas afetadas.

Effects of lactulose and silymarin on liver enzymes in cirrhotic rats.

Silymarin, a mixture of antihepatotoxic flavonolignans used in the treatment of liver diseases, and lactulose, a nonabsorbable synthetic disaccharide, were investigated to analyze their probable synergic and healing effects in a hepatic cirrhotic rat model. Liver damage was induced by the administration and subsequent withdrawal of thioacetamide. The significant decrease in liver enzymes and malondialdehyde levels confirmed the curative effects of silymarin and lactulose. In the silymarin + lactulose group, liver enzyme and malondialdehyde levels were significantly reduced compared with those in the thioacetamide group. All treatments led to liver regeneration and triggered enhanced regeneration. Silymarin and lactulose alone or in combination have potent curative effects and reduce thioacetamide-induced liver damage.

Rheum turkestanicum rhizomes possess anti-hypertriglyceridemic, but not hypoglycemic or hepatoprotective effect in experimental diabetes.

OBJECTIVE: Rheum turkestanicum (R. turkestanicum) rhizomes have been used in Iranain traditional medicine as an anti-diabetic agent. The purpose of the present investigation was to evaluate the anti-diabetic and antioxidant activities of R. turkestanicum rhizome extract in streptozotocin-induced diabetic rats. MATERIALS AND METHODS: Diabetes was induced by a single intraperitoneal injection of 55 mg/kg streptozotocin in male Wistar rats. Diabetic rats received the decoction extract of R. turkestanicum rhizomes at the doses of 200, 400 and 600 mg/kg daily by gavage for 3 weeks. Serum glucose and lipid levels were measured in all groups before diabetes induction and at the end of week 3. Oxidative stress was evaluated in the liver by measurement of malondialdehyde levels and total thiol concentration at the end of the experiment. RESULTS: A significant increase in serum glucose and triglyceride levels was observed in diabetic rats, which was accompanied by increased malondialdehyde levels and decreased total thiol concentration in the liver after 3 weeks. Treatment of diabetic rats with R. turkestanicum rhizome extract at the doses of 200, 400 and 600 mg/kg over a 3-week period did not change serum glucose, hepatic malondialdehyde and total thiol levels in diabetic rats. However, treatment with R. turkestanicum extract significantly decreased serum triglyceride levels in a dose-dependent manner at the end of the experiment. CONCLUSION: R. turkestanicum rhizome extract possess anti-hypertriglyceridemic, but not hypoglycemic or hepatoprotective effect in diabetic rats. Therefore, R. turkestanicum rhizome should be consumed with more caution by diabetic patients.

Renal injury, nephrolithiasis and Nigella sativa: A mini review.

OBJECTIVE: The incidence and prevalence of kidney stone is increasing worldwide. After the first recurrence the risk of subsequent relapses is higher and the time period between relapses is shortened. Urinary stones can be severely painful and make a huge economic burden. The stone disease may increase the vulnerability of patients to other diseases such as renal failure. Medicinal herbs are rich sources of antioxidants which are increasingly consumed globally for their safety, efficacy and low price. Nigella sativa is a spice plant that is widely used for prevention and treatment of many ailments in Muslim countries and worldwide. This review aims at investigation of the effects of Nigella sativa on renal injury and stone formation. MATERIALS AND METHODS: The scientific resources including PubMed, Scopus, and Google scholar were searched using key words such as: nephrolithiasis, urolithiasis, kidney/renal stone, renal injury, renal failure, urinary retention and black seed, black cumin, Nigella sativa and thymoquinone. RESULTS: N. sativa and its main component, thymoquinone showed positive effects in prevention or curing kidney stones and renal failure through various mechanism such as antioxidative, anti-inflammatory, anti-eicosanoid and immunomodulatory effects. The putative candidate in many cases has been claimed to be thymoquinone but it seems that at least in part, particularly in kidney stones, the herbal melanin plays a role which requires further investigation to prove. CONCLUSION: N. sativa and its components are beneficial in prevention and curing of renal diseases including nephrolithiasis and renal damages.

The Effects of Crocin on 6-OHDA-Induced Oxidative/Nitrosative Damage and Motor Behaviour in Hemiparkinsonian Rats.

BACKGROUND: Crocin is considered to prevent oxidative stress-related diseases, such as ischemia and Alzheimer's. The aim of the present investigation was to evaluate the effects of crocin on motor behaviour and 6-OHDA-induced oxidative/nitrosative damage to the striatum in an experimental model of Parkinson's disease. METHODS: Left medial forebrain bundle was lesioned by microinjection of 6-OHDA (16µg in 0.2% ascorbate-saline). Crocin (30 and 60 mg/kg) was injected intraperitoneally three days before surgery until six weeks. Rotational behaviour and biochemical analysis were used to evaluate the effect of crocin in a unilateral 6-OHDA-induced model of Parkinson's disease. RESULTS: The contralateral rotations induced by apomorphine in 6-OHDA lesioned group were highly significant (P < 0.001) as compared to the sham group. Moreover, chronic administration of crocin at doses of 30 and 60 mg/kg over six weeks did not change the rotations. The TBARS and nitrite levels in the striatum were also significantly (P < 0.05) increased in lesioned group. Treatment with crocin at a dose of 60 mg/kg significantly decreased the nitrite levels (P < 0.05) in the striatum. CONCLUSION: Crocin at a dose of 60 mg/kg could be effective in preventing the nitrosative damage in the striatum. Further investigations using higher doses of crocin is suggested to get the full neuroprotective effects of crocin in Parkinson's disease.

Effects of Hydroalcoholic Extract of Watercress (Nasturtium Officinale) Leaves on Serum Glucose and Lipid Levels in Diabetic Rats.

OBJECTIVE: Hyperlipidemia is a known complication of diabetes mellitus and predisposes to coronary heart disease. The lowering of total cholesterol and low density lipoprotein (LDL)-cholesterol should reduce the incidence of coronary disease. The aim of the present study was to examine the antihyperlipidemic and antidiabetic effects of the hydroalcoholic extract of watercress (Nasturtium officinale) leaves in streptozotocin-induced diabetic rats. METHODS: Female Wistar rats were randomly divided into 4 groups: control, diabetic and diabetic rats treated with the extract of watercress (Nasturtium officinale) at doses of 100 and 200 mg/kg. Diabetic rats received the watercress extract daily in drinking water for 4 weeks since the day after diabetes confirmation. The levels of serum glucose and lipids were spectrophotometrically measured in all groups at weeks 0 (before diabetes induction), 2 and 4. RESULTS: There was a significant increase in serum glucose, triglycerides, total cholesterol, and LDL-cholesterol in streptozotocin-induced diabetic rats, accompanied by a decrease in high density lipoprotein (HDL)-cholesterol. The treatment of diabetic rats with hydroalcoholic extract of watercress (Nasturtium officinale) leaves over a 4-week period significantly reduced serum glucose, total cholesterol and LDL- cholesterol in comparison with diabetic untreated rats. CONCLUSION: Our findings demonstrated that a 4-week treatment with watercress extract at a dose of 200 mg/kg has hypoglycemic and hypolipidemic effects in streptozotocin-diabetic rats. This implies that the consumption of watercress leaves can be helpful in reducing the complications of hyperglycemia and dyslipidemia associated with diabetes.