Bacopa monniera selectively attenuates suppressed Superoxide dismutase activity in Diazepam induced amnesic mice

Effects of chronic diazepam exposure on the behaviors and oxidative stress homeostasis in the eyes and brains of female Japanese medaka

Diazepam (DZP) residue has been frequently detected in wastewater, surface water, and groundwater due to its extensive use over the decades. In this study, we exposed female Japanese medaka (Oryzias latipes) to environmentally relevant doses of DZP (800 and 8000 ng/L) for 4 weeks, aimed to investigate their behavioral responses and possible links with ocular and brain oxidative stress homeostasis. As a result, DZP exposure could significantly reduce swimming activity (800 ng/L) and anxiety (800 and 8000 ng/L), indicating a sedative effect on medaka. The DZP exposure also significantly increased the social interaction in medaka at 8000 ng/L. Furthermore, exposure to DZP could alter the ocular and brain oxidative stress homeostasis in medaka. The ocular CAT activities significantly increased in the 800 ng/L-DZP groups, and the brain SOD, CAT, GST and MDA levels also significantly increased in both DZP exposure groups. Correlation analysis revealed that the ocular and brain oxidative stress induced by DZP exposure might play an important role in their behavioral toxicity to medaka. Our findings highlight the necessity to clarify the exact link between DZP exposure-induced oxidative stress in the neural and sensor systems and its behavioral toxicity to better assess the risks on nontarget aquatic species.

Mefenamic Acid Loaded and TPGS Stabilized Mucoadhesive Nanoemulsion for the Treatment of Alzheimer's Disease: Development, Optimization, and Brain-Targeted Delivery via Olfactory Pathway

Alzheimer's disease (AD) is a very common disorder that affects the elderly. There are relatively few medications that can be used orally or as a suspension to treat AD. A mucoadhesive (o/w) nano emulsion of mefenamic acid was made by adding Carbopol 940P to the optimised drug nanoemulsion using distilled water as the aqueous phase (6%); Solutol HS: tween 20 (3.6%) as the surfactant and co-surfactant; and clove oil: TPGS (0.4%) as the oil phase and mefenamic acid as the drug (2.8 mg/ml). The mucoadhesive nanoemulsion (S40.5%w/v) had a particle size of 91.20 nm, polydispersity index of 0.270, and surface charge of - 12.4 mV. Significantly higher (p < 0.001) drug release (89.37%) was observed for mucoadhesive drug formulation in comparison to mucoadhesive drug suspension (25.64%) at 8 h. The ex vivo nasal permeation of 83.03% in simulated nasal fluid and 85.71% in artificial cerebrospinal fluid was observed. The percent inhibition and inhibitory concentration (IC50) of mucoadhesive drug nanoemulsion were found to be 91.57 ± 2.69 and 6.76 respectively. Higher cell viability on glioblastoma cells (85-80%) was researched for mucoadhesive nanoemulsion as compared to drug suspension (80-70%). Significantly higher (p < 0.001) drug absorption and Cmax (491.94 ± 24.13 ng/ml) of mucoadhesive drug nanoemulsion were observed than mucoadhesive drug suspension (107.46 ± 11.46 ng/ml) at 8 h. The stability studies confirmed that the formulation was stable at 40°C ± 2°C and 75 ± 5% RH. The authors concluded that the mucoadhesive mefenamic acid-loaded nanoemulsion may be an effective technique for treating Alzheimer's disease by intranasal route.

A bacosides containing Bacopa monnieri extract alleviates allodynia and hyperalgesia in the chronic constriction injury model of neuropathic pain in rats

BACKGROUND

The current therapy of neuropathic pain is inadequate and is limited by the extent of pain relief and the occurrence of dose dependant side effects. Insufficient control of pain with conventional medications prompts the use of complementary and alternative medicine therapies by patients with neuropathic pain. This study therefore investigated a standardized methanolic extract of Bacopa monnieri, a widely reputed nootropic plant, for prospective antinociceptive effect in the chronic constriction injury (CCI) model of neuropathic pain.

METHODS

Placement of four loose ligatures around the sciatic nerve produced partial denervation of the hindpaw in rats. Bacopa monnieri (40 and 80 mg/kg, p.o) and the positive control, gabapentin (75 mg/kg, i.p), were administered daily after CCI or sham surgery and the behavioral paradigms of static- and dynamic-allodynia (paw withdrawal threshold to von Frey filament stimulation [PWT] and paw withdrawal latency to light-brushing [PWL]), cold-allodynia (paw withdrawal duration [PWD] to acetone), heat- (PWL to heat-stimulus) and punctate-hyperalgesia (PWD to pin-prick) were assessed on days 3, 7, 14 and 21.

RESULTS

CCI consistently generated static- (days 3-21), dynamic- (days 14-21) and cold-allodynia (days 3-21) plus heat- and mechano-hyperalgesia (days 3-21). The tested doses of Bacopa monnieri significantly attenuated the CCI-induced allodynia and hyperalgesia, exemplified by increased PWT (days 7-21), PWL to light brushing (days 14-21) and heat (days 7-21) as well as decreased PWD to pin prick and cold stimuli (days 3-21). The extract also counterbalanced the CCI-induced aberrations in the nociceptive behaviors by increasing the pain threshold to that of pre-surgery baseline. Gabapentin also afforded analogous beneficial behavioral profile but of higher magnitude.

CONCLUSIONS

Our findings suggest that Bacopa monnieri can be used as adjuvant therapy for neuropathic pain conditions afflicted with allodynia and hyperalgesia.

Anti-Alzheimer activity of isolated karanjin from Pongamia pinnata (L.) pierre and embelin from Embelia ribes Burm.f

Aim:

The aim of this study is to find out the anti-Alzheimer’s activity of isolated karanjin and embelin.

Materials and Methods:

Karanjin isolated from Pongamia pinnata (L.) pierre and embelin from Embelia ribes Burm.f. and their purity was confirmed by ultraviolet spectrophotometric and Thin layer chromatography based study. Anti-Alzheimer’s activity of isolated compounds were evaluated through elevated plus maze and Morris water maze model on Swiss albino mice. Diazepam (1 mg/kg body weight, intraperitoneally) was used for the induction of Alzheimer’s like effects (amnesia) on Swiss albino mice and piracetam (200 mg/kg body weight, oral) used as a standard treatment.

Results:

In EPM, embelin and karanjin decrease the transfer latency time in dose dependent manner and escape latency time in MWM method. A significant (P < 0.01) reduction in amnesia with an anti-Alzheimer’s effect found when results of isolated compounds were compared with standard and vehicle control. Diazepam (1 mg/kg) treated group showed significant increase in escape latency and transfer latency when compared with vehicle control; which indicates impairment in learning and memory.

Conclusion:

Both isolated compounds and standard significantly reversed the amnesia induced by diazepam and improved learning and memory of mice in dose and time dependent manner. This study supports the ethnobotanical use of these two plants in India for the management of nerve or brain related problems.

Low dose X-irradiation mitigates diazepam induced depression in rat brain

Depression is considered as one of the most prevalent health ailments. Various anti-depressant drugs have been used to provide succour to this ailment, but with little success and rather have resulted in many side effects. On the other hand, low dose of ionizing radiations are reported to exhibit many beneficial effects on human body by stimulating various biological processes. The present study was conducted to investigate the beneficial effects of low doses of X-rays, if any, during diazepam induced depression in rats. Female Sprague Dawley rats were segregated into four different groups viz: Normal control, Diazepam treated, X-irradiated and Diazepam + X-irradiated. Depression model was created in rats by subjecting them to diazepam treatment at a dosage of 2 mg/kg b.wt./day for 3 weeks. The skulls of animals belonging to X-irradiated and Diazepam + X-irradiated rats were X-irradiated with a single fraction of 0.5 Gy, given twice a day for 3 days, thereby delivered dose of 3 Gy. Diazepam treated animals showed significant alterations in the neurobehavior and neuro-histoarchitecture, which were improved after X-irradiation. Further, diazepam exposure significantly decreased the levels of neurotransmitters and acetylcholinesterase activity, but increased the monoamine oxidase activity in brain. Interestingly, X-rays exposure to diazepam treated rats increased the levels of neurotransmitters, acetylcholinesterase activity and decreased the monoamine oxidase activity. Further, depressed rats also showed increased oxidative stress with altered antioxidant parameters, which were normalized on X-rays exposure. The present study, suggests that low dose of ionizing radiations, shall prove to be an effective intervention and a novel therapy in controlling depression and possibly other brain related disorders.

Hippocampal and striatal histomorphology following chronic nicotine administration in female and male rats

Background

Nicotine is a subject of continuous research because of its likely ameliorative effects on neurologic and neurodegenerative disorders.

Purpose

This study examined the effects of its chronic subcutaneous administration on hippocampal and striatal microstructure in both female and male rats.

Methods

Forty adult female and male Wistar rats were divided into 4 groups. Three experimental groups were administered nicotine via subcutaneous injections at doses of 0.25, 2 and 4 mg/kg body weight for 28 days. Control groups received normal saline. Following administration, routine processing of brain tissues was carried out. Sections obtained were stained using routine H&E methods for general histological appearance, Cresyl violet methods for nissl substances, and Bielschwolsky silver impregnation method for neuritic plaques and neurofibrillary tangles.

Results

The study showed significant increase in percentage of neurons showing degenerating features in the hippocampus and striatum of both female and male rats following the higher doses of nicotine treatment. Only female rats showed positive agyrophilic (black-coloured) aggregations in the hippocampal and striatal regions after nicotine treatment.

Conclusion

The present study indicates that higher dose of chronic nicotine administration may induce hippocampal and striatal neurodegenerative changes. However, further studies using more specific method for studying neurodegeneration within brain regions is recommended.

Study of CNS depressant and behavioral activity of an ethanol extract of Achyranthes Aspera (Chirchita) in mouse model

Background

Achyranthes Aspera Linn., known as Chirchira (Hindi), Agadha (Marathi) is an indigenous herb found in India. The herb has been reported to have variety of activities like antifertility, antihyperlipidemic, antidiabetic, immunomodulatory, anticarcinogenic, diuretic and cardiotonic, analgesic, anti-inflammatory, hypnotic, antifungal and antibacterial activity. It has been also reported to have central anti-nociceptive activity in thermal induced pain methods in our earlier studies. We wanted to study its neuropharmacological effects, which may throw light on understanding the underlying mechanism for its central activity.

Purpose

The present study was designed to evaluate CNS depressant and behavioral effects of A. Aspera extract and to study the phytochemical responsible for these activities with possible mode of action.

Methods

The effects on behavioral activity was studied using open field test (OFT). The extract was given intraperitoneally at a dose of 400 mg/kg. Diazepam (2mg/kg body weight i.p.) was used as standard. Data was analyzed by ANOVA test followed by Dunnett’s test. All the results were expressed as Mean (±SEM). P <0.05 was considered significant.

Results

Phytochemical screening revealed presence of triterpenoids, saponins, alkaloids (betaine, achyranthine) and steroids as major constituents. The result of the study demonstrated that ethanol extract of A. Aspera (400 mg/kg i.p.) decreased locomotor activity, produced muscle relaxation and showed antianxiety activity.

Conclusions

Ethanols extract of A. Aspera exhibit CNS depressant action and significant anxiolytic activity comparable to diazepam.

D, Rao A.S.R. S, Sri G K. Antidepressant activity of brahmi in albino mice

CONTEXT

In traditional system of medicine brahmi has been used to enhance memory. Recently it has been reported to have action in psychiatric disorders. With these backgrounds the work has been undertaken to study antidepressant activity of brahmi in albino mice.

AIM

To evaluate antidepressant activity of brahmi in experimental models.

MATERIALS AND METHODS

The antidepressant activity was studied in albino mice using forced swimming test (FST), tail suspension test (TST) and shock induced depression (SID). Imipramine (10mg/kg), fluoxetine (30mg/kg) were used as standard drugs and brahmi (10, 20, 30mg/kg) was used as test drug.

RESULTS

Brahmi exhibited significant decrease in duration of immobility in FST and reduced the shock induced decrease in activity in SID models. It didn't show any activity in the TST model.

CONCLUSION

Brahmi has shown antidepressant activity in FST and SID.