Potential role of licofelone,minocycline and their combination against chronic fatigue stress induced behavioral,biochemical and mitochondrial alterations in mice

BackgroundChronic fatigue stress (CFS) is a common complaint among general population. Persistent and debilitating fatigue severely impairs daily functioning and is usually accompanied by combination of several physical and psychiatric problems. It is now well established fact that oxidative stress and neuroinflammation are involved in the pathophysiology of chronic fatigue and related disorders. Targeting both COX (cyclooxygenase) and 5-LOX (lipoxygenase) pathways have been proposed to be involved in neuro-protective effect.MethodsIn the present study, mice were put on the running wheel apparatus for 6 min test session daily for 21 days, what produced fatigue like condition. The locomotor activity and anxiety like behavior were measured on 0, 8^th, 15^th and 22^nd day. The brains were isolated on 22^nd day immediately after the behavioral assessments for the estimation of oxidative stress parameters and mitochondrial enzyme complexes activity.ResultsPre-treatment with licofelone (2.5, 5 and 10 mg/kg, po) and minocycline (50 and 100 mg/kg, po) for 21 days, significantly attenuated fatigue like behavior as compared to the control (rotating wheel activity test session, RWATS) group. Further, licofelone (5 and 10 mg/kg, po) and minocycline (50 and 100 mg/kg, po) drug treatments for 21 days significantly attenuated behavioral alterations, oxidative damage and restored mitochondrial enzyme complex activities (I, II, III and IV) as compared to control, whereas combination of licofelone (5 mg/kg) with minocycline (50 mg/kg) significantly potentiated their protective effect which was significant as compared to their effect per se.ConclusionThe present study highlights the therapeutic potential of licofelone, minocycline and their combination against CFS in mice.     

Venlafaxine reverses chronic fatigue-induced behavioral, biochemical and neurochemical alterations in mice

A state of chronic fatigue was produced in mice by subjecting them to forced swim inside a rectangular jar of specific dimensions everyday for a 6 min session for 15 days. Immobility period was recorded on alternate days. The effect of venlafaxine, a dual reuptake inhibitor of serotonin and norepinephrine was evaluated in this murine model of chronic fatigue. Venlafaxine was administered daily and on the days of testing, it was injected 30 min before forced swim session. On the 16th day i.e. 24 h after the last dose of venlafaxine, various behavioral, biochemical and neurotransmitter estimations in the brain were carried out. There was a significant increase in immobility period in vehicle treated mice on successive days, the maximum immobility score reaching on the 7th day and sustained till 15th day. Behavioral parameters revealed hyperlocomotion, anxiety response, muscle incoordination, hyperalgesia and memory deficit. Biochemical analysis showed a significant increase in lipid peroxidation, nitrite and myeloperoxidase levels and a decrease in the reduced glutathione (GSH) levels in brain homogenates. Further, there was a decrease in adrenal ascorbic acid following chronic forced swim. The neurotransmitter estimations in the brain samples revealed a decrease in norepinephrine, serotonin and dopamine levels on chronic exposure to forced swim for 15 days. Daily treatment with venlafaxine (8 and 16 mg/kg, i.p.) for 15 days produced a significant reduction in immobility period and reversed various behavioral, biochemical and neurotransmitter alterations induced by chronic fatigue. Venlafaxine could be of therapeutic potential in the treatment of chronic fatigue.     

Possible GABAergic mechanism in the neuroprotective effect of gabapentin and lamotrigine against 3-nitropropionic acid induced neurotoxicity

Huntington's disease is a progressive neurodegenerative disorder that gradually reduces memory, cognitive skills and normal movements of affected individuals. Systemic administration of 3-Nitropropionic acid induces selective striatal lesions in rodents and non-human primates. Therefore, the present study has been designed to elucidate the comparative mechanistic profile of gabapentin, lamotrigine and their interactions with GABAergic modulators against 3-Nitropropionic acid induced neurotoxicity. Systemic 3-Nitropropionic acid (10 mg/kg) administration for 14 days significantly reduced body weight, locomotor activity, grip strength, oxidative defense (LPO, nitrite, SOD and catalase) and impaired mitochondrial complex enzyme (I, II, IV and MTT assay) activities in the striatum. 3-Nitropropionic acid treatment also increased TNF-α level in the striatum. Gabapentin (50 and 100 mg/kg) and lamotrigine (10, 20 and 40 mg/kg) treatments significantly restored behavioural, oxidative defense and mitochondrial complex enzyme activities and proinflammatory markers (TNF-α) as compared to 3-Nitropropionic acid treated group. Systemic picrotoxin (1 mg/kg) pretreatment with sub effective dose of gabapentin (50 mg/kg) or lamotrigine (20mg/kg) significantly attenuated their protective effect. Further, GABA (50 mg/kg) and/or muscimol (0.05 mg/kg) pretreatment with sub effective dose gabapentin (50 mg/kg) and lamotrigine (20 mg/kg) significantly potentiated their protective effects which were significant as compared to their effect alone. The results of the present study suggest that a GABAergic mechanism is involved in the protective effect of gabapentin and lamotrigine against 3-Nitropropionic acid induced neurotoxicity.     

Potential role of pioglitazone,caffeic acid and their combination against fatigue syndrome-induced behavioural,biochemical and mitochondrial alterations in mice

Chronic fatigue is an illness characterised by persistent and relapsing fatigue, often accompanied by numerous neuropsychiatric problems, such as anxiety and depression. The aetiology of chronic fatigue remains unclear so far. However, recent studies suggested the involvement of oxidative stress in this chronic debilitating disease. Alternatively, antioxidants have also been reported to have beneficial effect against chronic fatigue-like conditions. Therefore, present study has been designed to explore the potential role of pioglitazone, caffeic acid and their combination against chronic fatigue-like condition in mice. In the experimental protocol, the mice were put on the running wheel apparatus for 6 min test session daily for 21 days which produced fatigue-like condition. The locomotor activity and anxiety levels were measured on 0, 8th, 15th and 22nd days. The brains were isolated on 22nd day immediately after the behavioural assessments, oxidative damage and mitochondrial enzyme complexes were then estimated subsequently. Three weeks pioglitazone (5 and 10 mg/kg) and caffeic acid (5 and 10 mg/kg) pretreatment significantly attenuated the chronic fatigue-like condition (restored running wheel activity, locomotor activity and reduced anxiety-like behaviour) as compared to that in control (chronic fatigue) animals. Further, pioglitazone (5 and 10 mg/kg) and caffeic acid (5 and 10 mg/kg) drug treatments for 3 weeks significantly attenuated oxidative damage (decreased lipid peroxidation, nitrite concentration, restored reduction in glutathione and catalase levels), altered mitochondrial enzymes complex (I, II and IV) activities and mitochondrial redox activity (MTT assay) when compared with control. Further, combination of lower dose of pioglitazone (5 mg/kg) and caffeic acid (5 mg/kg) showed significant synergism in their protective effect which was significant as compared to their effect per se. The present study highlights the potential role of pioglitazone, caffeic acid and their combination in the pathophysiology of chronic fatigue-like condition in mice.     

Diphenylhydantoin potentiates the protective effect of diazepam against pentylenetetrazol but not against bicuculline and isoniazid-induced seizures in mice

The anticonvulsant activity of diazepam alone, or in combination with diphenylhydantoin was studied in pentylenetetrazol-, bicuculline- and isoniazid-induced Scizures. Alone, diphenylhydantoin did not influence the chemically-induced convulsions but enhanced the antipentylenetetrazol action of diazepam whilst failing to affect the protective effect of the benzodiazepine against bicuculline- and isoniazid-induced convulsions. It is suggested that a diphenylhydantoin-induced increase in the total number of specific benzodiazepine binding sites might be responsible for the enhancement of the antipentylenetetrazol activity of diazepam. The anticonvulsant action of diazepam against bicuculline and isoniazid-induced Scizures does not seem to involve an interaction with benzodiazepine receptors.     

Absence epilepsy and regional blood-brain barrier permeability: the effects of pentylenetetrazole-induced convulsions.

This study was designed to evaluate the blood-brain barrier permeability characteristics of the WAG/Rij strain of rats that are an ideal model for human absence epilepsy, in controls and pentylenetetrazole-induced seizures conditioned to Evans blue-albumin. For this, WAG/Rij and Wistar rats were treated with either saline or 55 mg kg-1 pentylenetetrazole i.v. after the rats were injected with 3 ml kg-1 of 2% Evans blue. Total duration of seizure activity and regional blood-brain barrier permeability changes were determined and compared with control Wistar rats. The duration of convulsive activity which was induced by pentylenetetrazole was significantly longer in WAG/Rij rats than in Wistar rats. The blood-brain barrier opening to Evans blue was not the case in saline- injected WAG/Rij or Wistar rats, but this was clearly seen in both strains after pentylenetetrazole-induced convulsions. EB leakage was mainly seen in the cortical areas, cerebellum, pons, thalamus, hypothalamus and corpus striatum of WAG/Rij rat brain, whereas this was recorded in the preoptic area, bulbus olfactorius, midbrain, hypothalamus, corpus striatum and inferior colliculus of the Wistar rats brain. As a result, the WAG/Rij rats were more susceptible than Wistar rats to PTZ-induced generalised tonic-clonic convulsions, and a different pattern in PTZ-induced changes in BBB permeability was observed between WAG/Rij rats and Wistar rats.     

Possible nitric oxide modulation in protective effect of FK-506 against 3-nitropropionic acid-induced behavioral,oxidative, neurochemical,and mitochondrial alterations in rat brain

FK-506 is an immunosuppressant being widely used for allograft rejection cases in the present clinical scenario. Recently, the neuroprotective effect of FK-506 has also been reported against a number of neurodegenerative diseases in rodents. This study was designed to explore the possible protective effect of FK-506 and its interaction with nitric-oxide modulators against 3-nitropropionic acid (3-NP)-induced behavioural, biochemical, neurochemical, and mitochondrial alterations in striatum, cortex, and hippocampus regions of the brain. Systemic administration of 3-nitropropionic acid produces Huntington-like symptoms in rats. 3-NP (10?mg/kg) treatment for 14 days impaired locomotor activity, grip strength, and body weight. 3-NP treatment significantly raised malondialdehyde, nitrite concentration, depleted antioxidant enzymes (SOD and catalase), and levels of bioamines (dopamine and norepinephrine) in striatum, cortex, and hippocampus areas of rat brain. Significant alterations in mitochondrial enzyme complexes (I, II, and IV) activities and mitochondrial redox activity have also been altered significantly by 3-NP. Pretreatment with FK-506 (0.5, 1, and 2?mg/kg) significantly reversed these behavioral, biochemical, and cellular alterations. L-arginine treatment with a subeffective dose FK-506 (1?mg/kg) reversed the protective effect of FK-506. However, L-NAME pretreatment with FK-506 (1?mg/kg) potentiated the protective effect of FK-506. The present study shows that FK-506 attenuates 3-NP-induced neurotoxicity and nitric-oxide modulation might be involved in its protective action.     

Neuroprotective effect of carvedilol against aluminium induced toxicity: possible behavioral and biochemical alterations in rats

Aluminium, is a trace element available in the Earth's crust naturally and has a toxic potential for humans. It has been suggested as a contributing factor in the pathogenesis of Alzheimer's disease. β-Adrenoceptor blocking agents (β-blockers) have been established as therapeutics for the treatment of patients with hypertension, ischemic heart diseases, chronic heart failure, arrhythmias and glaucoma. Over the years, however, β-blockers have been associated with an incidence, albeit low, of central nervous system (CNS) side effects. In addition, noradrenergic receptors play a modulatory role in many nerve functions, including vigilance, attention, reward, learning and memory. Therefore, the present study has been designed to explore the possible role of carvedilol, an adrenergic antagonist against aluminium chloride-induced neurotoxicity in rats. Aluminium chloride (100 mg/kg) was administered daily for six weeks that significantly increased cognitive dysfunction in the Morris water maze and oxidative damage as indicated by a rise in lipid peroxidation and nitrite concentration and depleted reduced glutathione, superoxide dismutase, catalase and glutathione S-transferase activity compared to sham treatment. Chronic aluminium chloride treatment also significantly increased acetylcholinesterase activity and the aluminium concentration in brain compared to sham. Chronic administration of carvedilol (2.5 and 5 mg/kg, po) daily to rats for a period of 6 weeks significantly improved the memory performance tasks of rats in the Morris water maze test, attenuated oxidative stress (reduced lipid peroxidation, nitrite concentration and restored reduced glutathione, superoxide dismutase, catalase and glutathione S-transferase activity), decreased acetylcholinesterase activity and aluminium concentration in aluminium-treated rats compared to control rats (p < 0.05). Results of this study demonstrated the neuroprotective potential of carvedilol in aluminium chloride-induced cognitive dysfunction and oxidative damage.     

Protective effect of alprazolam in acute immobilization stress-induced certain behavioral and biochemical alterations in mice

Stress can be viewed as a cause of adverse circumstance that induces a wide range of biochemical and behavioral changes. Oxidative stress is a major contributor to the genesis of neurodegenerative and neuropsychiatric problems. In the present study, we investigated the protective effect of alprazolam in acute immobilization-induced various behavioral and biochemical alteration in mice. Mice were immobilized for a period of 6 h. Alprazolam (0.25 and 0.5 mg/kg, i.p.) was administered 30 min before subjecting the animals to acute stress and several behavioral (mirror chamber, actophotometer, tail flick test) and biochemical tests (malondialdehyde level, glutathione, catalase, nitrite and protein) were performed. Acute immobilization stress for a period of 6 h caused severe anxiety, analgesia and decreased locomotor activity in mice. Biochemical analyses revealed an increase in malondialdehyde, nitrite level and depleted glutathione and catalase activity in stressed brain. Pretreatment with alprazolam (0.25 and 0.5 mg/kg, i.p.) significantly reversed immobilization stress-induced anxiety, analgesia and impaired locomotor activity. Biochemically, alprazolam pretreatment decreased malondialdehyde, nitrite activity and restored reduced glutathione level and catalase activity. These results suggest that alprazolam has a neuroprotective effect and can be used in the treatment and management of stress and related disorders.     

Effects of gabapentin and antidepressant drug combinations on convulsions and memory in mice

In epileptic patients, neurobehavioral problems such as cognitive impairment, depression, and psychosocial impairments have been described, which may have a pathological and/or iatrogenic basis. For this reason additional treatment is required, beside antiepileptic drug (AED) therapy, to correct the accompanying neurological deficits. However, the rationale behind use of antidepressants along with antiepileptics has been questioned due to proconvulsant effects of the former. In the present study, the effect of gabapentin (GBP) on seizure score and memory is evaluated when it is given alone and in combination with some antidepressants, such as sertraline (SERTR) and alprazolam (ALP). Pentetrazole (PTZ)-induced convulsion and spontaneous alternation behavior (SAB) models were used to study the anticonvulsant effect and effect on memory, respectively. Results showed that addition of SERT to GBP or ALP resulted in reduction of anticonvulsant efficacy of these drugs. However, the combination of GBP + SERT + ALP was superior as far as effect on seizure severity and memory was concerned.     

Brain targeted oral delivery of doxycycline hydrochloride encapsulated Tween 80 coated chitosan nanoparticles against ketamine induced psychosis: behavioral,biochemical, neurochemical and histological alterations in mice

To develop statistically optimized brain targeted Tween 80 coated chitosan nanoparticulate formulation for oral delivery of doxycycline hydrochloride for the treatment of psychosis and to evaluate its protective effect on ketamine induced behavioral, biochemical, neurochemical and histological alterations in mice. 3² full factorial design was used to optimize the nanoparticulate formulation to minimize particle size and maximize entrapment efficiency, while independent variables chosen were concentration of chitosan and Tween 80. The optimized formulation was characterized by particle size, drug entrapment efficiency, Fourier transform infrared, Transmission electron microscopy analysis and drug release behavior. Pure doxycycline hydrochloride (25 and 50?mg/kg, p.o.) and optimized doxycycline hydrochloride encapsulated Tween 80 coated chitosan nanoparticles (DCNP_opt) (equivalent to 25?mg/kg doxycycline hydrochloride, p.o.) were explored against ketamine induced psychosis in mice. The experimental studies for DCNP_opt, with mean particle size 237?nm and entrapment efficiency 78.16%, elucidated that the formulation successfully passed through blood brain barrier and exhibited significant antipsychotic activity. The underlying mechanism of action was further confirmed by behavioral, biochemical, neurochemical estimations and histopathological study. Significantly enhanced GABA and GSH level and diminished MDA, TNF-α and dopamine levels were observed after administration of DCNP_opt at just half the dose of pure doxycycline hydrochloride, showing better penetration of doxycyline hydrochloride in the form of Tween 80 coated nanoparticles through blood brain barrier. This study demonstrates the hydrophilic drug doxycycline hydrochloride, loaded in Tween 80 coated chitosan nanoparticles, can be effectively brain targeted through oral delivery and therefore represents a suitable approach for the treatment of psychotic symptoms.     

Meperidine and normeperidine convulsions in mice: Possible opiate and serotonergic mechanisms

The effects of naloxone and 5-hydroxytryptophan (5-HTP) pretreatment on convulsions induced by meperidine and normeperidine were studied in male Swiss-Webster mice. The CD50 (95% confidence limits) was found to be 17.5 mg/kg (15.6–19.6) for meperidine and 38.0 mg/kg (36.2–39.9) for normeperidine administered intravenously. Convulsions induced by meperidine (17.5 mg/kg) were significantly attenuated by naloxone (30 mg/kg) pretreatment but not by 5-HTP pretreatment alone. Normeperidine (38.0 mg/kg) induced convulsions were significantly attenuated by 5-HTP pretreatment, but not by naxolone pretreatment. The administration of a combined dose of meperidine and normeperidine does not produce a supra-additive response.     

Rofecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor potentiates the anticonvulsant activity of tiagabine against pentylenetetrazol-induced convulsions in mice

Numerous studies have implicated prostaglandins as potential modulators in seizure activity. The objective of the present study was to elucidate the effect of rofecoxib (selective COX-2 inhibitor) alone or in combination with newer antiepileptic drug tiagabine (γ-amino acid reuptake inhibitor) against pentylenetetrazol (PTZ) (80 mg/kg, i. p.)-induced chemoconvulsions in mice. Rofecoxib or tiagabine was administered 45 min prior to the PTZ challenge. In combination study, rofecoxib was administered 10 min before tiagabine and after 35 min the animals were challenged with convulsive dose of PTZ. Mean onset time of jerks, clonus and extensor phases following PTZ challenge was noted. Pretreatment with rofecoxib (1–5.0 mg/kg, i. p.) or tiagabine (1–10 mg/kg, i. p.) dose dependently protected the animals against PTZ-induced convulsions. The mean onset time of jerks, clonus and extensor phase were increased. A subeffective dose of rofecoxib (0.5 mg/kg, i. p.) potentiated the effect of subprotective dose of tiagabine (0.5 mg/kg, i. p.). The results of the present study suggested that the protective effect of rofecoxib, a COX-2 inhibitor against PTZ-induced convulsions may be possibly through the GABAergic modulation. Rofecoxib may have a place as adjuvant therapy with standard antiepileptic drugs such as tiagabine in the treatment of epilepsy. Received 10 August 2006; revised and accepted 30 August 2006     

Chicoric acid regulates behavioral and biochemical alterations induced by chronic stress in experimental Swiss albino mice

The present study was taken up to see the effect of chicoric acid (CA) on behavioral and biochemical alterations induced by chronic restraint stress in experimental Swiss albino mice. CA at 1 mg/kg dose level exhibited considerable antidepressant activity as shown by significant decrease in immobility period in the Porsolt's swim stress-induced behavioral despair test and escape failures in Learned “helplessness test”. The antidepressant activity shown by CA can be attributed to its modulating effect on nor-adrenaline (NA), dopamine (DA) and 5- hydroxy tryptamine (5-HT) as shown by their quantification in CA treated chronically stressed mice. Further, a significant antioxidant effect was exhibited by CA as shown by estimation of lipid peroxidation, glutathione (GSH) and glycogen in liver of chronically stressed mice. It also normalized altered values of serum glucose, triglycerides, aspartate aminotransferase (AST) alanine aminotransferase (ALT) and alkaline phosphatase (ALP) in a dose dependent manner. The stress busting potential of CA was further confirmed by its regulating effect on raised plasma corticosterone levels and significant attenuation of the depleted ascorbic acid, cholesterol and corticosterone levels in adrenal glands. Thus, our results suggest that CA possesses considerable stress busting potential, and that anti-oxidation may be one of the mechanisms underlying its antistress action.     

Inhibitory and stimulatory effects of morphine on locomotor activity in mice: biochemical and behavioral studies

A possible interaction between the opposite effect (inhibition and stimulation) of morphine on locomotor activity in mice and monoaminergic systems in the striatum was studied. Ten minutes after systemic administration, morphine at 1.25 mg/kg decreased locomotor activity and the levels of 3-methoxytyramine (3-MT), whereas at 20 mg/kg locomotor activity and 3-MT levels increased. At the same time, no change in the other monoamine metabolite (DOPAC, HVA, MHPG, and 5-HIAA) levels was observed. Sixty minutes after administration, morphine at 1.25 mg/kg did not induce any change in locomotor activity or in all the monoamine metabolite levels measured. On the other hand, morphine at 20 mg/kg maintained an initial increase in locomotor activity and increased not only 3-MT levels, but also other metabolite (DOPAC, HVA, MHPG, and 5-HIAA) levels. These results suggest that, at low dosages, the inhibitory effect of morphine on locomotor activity in mice may be related to a decrease of the presynaptic dopamine release in the striatum and that the stimulatory effect of morphine, at high dosages, may be related to an increase of the presynaptic dopamine release in the striatum.     

Effect of carvedilol on behavioral, mitochondrial dysfunction, and oxidative damage against d-galactose induced senescence in mice

Growing evidence indicates that oxidative stress and mitochondrial dysfunction plays a critical role in brain aging. Chronic injection of d-galactose can cause gradual deterioration in learning and memory capacity and serve as an animal model of aging. Recently, potential therapeutic effect of carvedilol (CAR) has been reported by virtue of which its antioxidant and mitochondrial permeability transitional property. The present study has been designed to explore the CAR effect against d-galactose-induced behavioral, biochemical, and mitochondrial dysfunction in mice. Systemic administration of d-galactose for 6 weeks significantly impaired behavioral (learning and memory and locomotor activity), biochemical parameters (raised lipid peroxidation, nitrite concentration, depletion of reduced glutathione, and catalase activity), and mitochondrial enzymes (decreased complex I, II and III enzymes levels) as compared to sham group. CAR (2.5 and 5 mg/kg) treatment significantly improved behavioral abnormalities and biochemical and cellular alterations as compared to control. Chronic administration of d-galactose for a period of 6 week results into a significant increase of acetylcholine esterase enzyme level. CAR (2.5 and 5 mg/kg) treatment significantly attenuated the elevated level of acetylcholine esterase of mice. In conclusion, present studies highlight the protective effects of CAR against d-galactose-induced behavioral, biochemical, and mitochondrial dysfunction in mice. The study further provides a hope that CAR could be used in the management of cognitive dysfunction and related symptoms during aging.     

Effect of chronic lithium treatment on isolation-induced behavioral and biochemical effects in mice

The following effects were induced in mice by a prolonged of isolation (6-7 weeks from weaning): (1) reduction in motor activity; (2) reduction in the effect of oxotremorine on rectal temperature; (3) increase in the response to salbutamol, a beta-adrenergic stimulant. Chronic lithium treatment (2 mg/ml in the drinking water during the last 3-4 weeks of isolation) prevented these phenomena. The number and affinity of beta-adrenergic receptors in the whole mouse brain (excluding the cerebellum) was unmodified by either isolation or by lithium. It is suggested that lithium blocks isolation-induced hypersensitivity, especially of the beta-adrenergic system; this mechanism may be involved in the therapeutic action of lithium.