Scopolamine-induced Memory Impairment In Mice Research Articles

Effects of Piper nigrum fruit and Cinnamum zeylanicum bark alcoholic extracts, alone and in combination, on scopolamine-induced memory impairment in mice

Background and purpose:Alzheimer’s disease is a progressive brain disorder that is thought to be triggered via disruption of cholinergic neurons and enhanced oxidative stress. Therefore, antioxidant phytochemicals with the ability to fortify cholinergic function should help in preventing the progress of the disease. This study aimed at evaluating the combinational effects of two popular herbs one with anticholinesterase activity namely Piper nigrum and the other with antioxidant capacity, Cinnamomum zeylanicum.Experimental approach:In this study, P. nigrum extract (PN) (50, 100 mg/kg, ip) and C. zeylanicum extract (CZ) (100, 200, 400 mg/kg, ip) and their combinations were administered for 8 days before the injection of scopolamine (1 mg/kg, ip). Mice were then tested for their memory using two behavioral models, namely the object recognition test and the passive avoidance task.Findings/Results:Administration of scopolamine significantly impaired memory performance in both memory paradigms. In the passive avoidance test (PAT) model, PN at doses up to 100 mg/kg and CZ at doses up to 400 mg/kg did not significantly alter the memory impairment induced by scopolamine. The combination of these two plant extracts did not change the PAT parameters. In the object recognition test (ORT) model, however, administration of 100 mg/kg CZ alone and a combination of PN (50 mg/kg) with CZ (400 mg/kg), significantly increased the recognition index (P < 0.05).Conclusion and implications:Two plant extracts when administered alone or in combinations affected the memory performance differently in two memory paradigms. In the PAT model, the extracts did not show any memory improvement, in ORT, however, some improvements were observed after plant extracts.

Phenolic Profiling and Therapeutic Potential of Certain Isolated Compounds from Parkia roxburghii against AChE Activity as well as GABAA α5, GSK-3β, and p38α MAP-Kinase Genes.

Parkia roxburghii belongs to the family Mimosaceae; it has been used since ancient times as a cure for different health complications; such as inflammatory and gynecological diseases and hemiplegia. In this investigation, a reversed-phase-high-performance liquid chromatography (RP-HPLC) profile was carried out for P. roxburghii; also, the isolated bioactive compounds including quercetin, catechin, and biochaninA were individually and/or in combination investigated for their inhibitory effects on scopolamine-induced memory impairments in mice, implying that they have the ability to reduce the neurodegenerative effects of scopolamine and thus could be employed as a more effective therapeutic agent in the treatment of Alzheimer’s disease (AD) in humans. The possible interactions of Parkia flavonoids with acetylcholinesterase (AChE), γ-aminobutyric acid A receptor, alpha5 (GABAA α5), glycogen synthase kinase-3 (GSK-3), p38 mitogen-activated protein kinase (p38MAP-kinase), signal-regulated kinase (ERK), and protein-serine/threonine kinase (Akt) were then determined using molecular docking.

Dietary supplementation with Ceriporia lacerata improves learning and memory in a scopolamine-induced amnesia mouse model.

The online version contains supplementary material available at 10.1007/s10068-021-00945-5.

Aripiprazole ameliorates scopolamine-induced amnesia in mice

Aripiprazole, a known third generation anti-psychotic drug. The drug has shown to have lesser side effects on extrapyramidal system and enhance memory when compared with the first-generation anti-psychotic drugs. However, studies on the impact of aripiprazole on scopolamine-induced memory impairment in mice have been poorly reported. This study was designed to investigate the impact of aripiprazole on scopolamine-induced amnesia in mice. Thirtysix (36) mice weighing between 20-23g were randomly divided into six groups. Group 1 was given 10 ml/kg distilled water. Group 2 received 3 mg/kg scopolamine alone. Group 3 was given 1 mg/kg donepezil. Group 4 received 0.5 mg/kg aripiprazole. Group 5 was given 0.3 mg/kg aripiprazole. Group 6 received 0.1mg/kg aripiprazole. Thirty minutes after administration of either aripiprazole or donepezil, scopolamine (3 mg/kg) was administered, intraperitoneally. The administration was for 7days, during which their memory was assessed using Morris water maze and Y-maze models. The results showed that the anti-amnesic effect of aripiprazole appeared to be dosedependent; the animals administered with 0.5 mg/kg aripiprazole showed the greatest improved memory performance against scopolamine-induced amnesia. The hippocampal and prefrontal cortex tissues displayed anti-amnesic potential of aripiprazole. Aripiprazole seems to improved memory performance against scopolamine-induced memory impairment in mice.&#x0D; Keywords: Aripiprazole; Anti-amnesic; Scopolamine; Memory

Phytochemical Analysis, In Vitro Anticholinesterase, Antioxidant Activity and In Vivo Nootropic Effect of Ferula ammoniacum (Dorema ammoniacum) D. Don. in Scopolamine-Induced Memory Impairment in Mice.

Background: Ferula ammoniacum (D. Don) is one of the endemic medicinal plants that is traditionally used to treat a number of diseases. Although the plant has been used to enhance memory, the investigational evidence supporting the nootropic effect was unsubstantial. Hence, the rationale for this study was to assess the potential beneficial effect of F. ammoniacum seed extracts on learning and memory in mice. Methods: The powdered plant samples (aerial parts) were subjected to extraction ad fractionation. Among the extracts, crude and ethyl acetate extracts were screened for major phytochemicals through HPLC analysis. All the extracts were evaluated for the in vitro anticholinesterase (AChE and BChE) and antioxidant potentials. Among the extracts the active fraction was further assessed for improving learning and memory in mice using behavioural tests like Y-maze and novel object recognition test (NORT) using standard protocols. After behavioural tests, all the animals were sacrificed and brains tissues were assessed for the ex vivo anticholinesterase and antioxidant potentials. Results: Phytochemicals like chlorogenic acid, quercetin, mandelic acid, phloroglucinol, hydroxy benzoic acid, malic acid, epigallocatechin gallate, ellagic acid, rutin, and pyrogallol were identified in crude methanolic extract (Fa.Met) and ethyl acetate fraction (Fa.EtAc) through HPLC. Fa.EtAc and Fa.Chf extracts more potently inhibited AChE and BChE with IC50 values of 40 and 43 µg/mL, and 41 and 42 µg/mL, respectively. Similarly highest free radical scavenging potential was exhibited by Fa.EtAc fraction against DPPH (IC50 = 100 µg/mL) and ABTS (IC50 = 120 µg/mL). The extract doses, 100 and 200 mg/kg body weight significantly (p < 0.01) improved the short-term memory by increasing the percent spontaneous alternation in the Y-maze test along with increasing discrimination index in the NORT that clearly indicated the enhancement in the recognition memory of mice. Conclusion: The extracts more potently scavenged the tested free radicals, exhibited anticholinesterase activities, improved the learning abilities and reduced the memory impairment induced by scopolamine in mice model thus suggesting that these extracts could be effectively used for the management of oxidative stress, neurodegenerative diseases and memory loss.

Scopolamine으로 유도한 기억력 저하 마우스에 대한적치커리 추출물의 개선효과

We investigated the protective effects and mechanisms of red chicory extract (RCE) on scopolamine-induced memory impairment in mice. Antioxidant effects were investigated by measuring DPPH radical scavenging activity, and cell viability and intracellular ROS levels were examined by inducing cytotoxicity with L-glutamate in HT-22 cells. In addition, mice were administered orally with RCE (150 and 300 mg/kg). Memory was evaluated using Morris water maze (MWZ) and passive avoidance tests. Administration of SRCE 150 kg/mg significantly increased escape latency time (p&lt;0.05) that was shortened by scopolamine. It further increased platform crossing numbers after 7 days of training in MWZ tests (p&lt;0.05), which were significantly shortened by scopolamine, and prolonged latency (p&lt;0.01) in passive avoidance tests. Biochemical findings showed significantly increased total glutathione (GSH) (p&lt;0.05), glutathione S-transferase (GST) (p&lt;0.01), and glutathione peroxidase (GPx) (p&lt;0.01) in the mice administered RCE 150 mg/kg compared with the scopolamine-induced positive control. Glutathione reductase (GR) did not significantly differ between the RCE 300 mg/kg and scopolamine-induced groups (p&lt;0.05). These results suggested that RCE has antioxidant activity and enhances scopolamine-induced cognitive impairment by attenuating oxidative stress.

Effect of Original Peptide Derivatives of Galantamine on Passive Avoidance in Mice.

The effect of original peptide derivatives of galantamine on scopolamine-induced memory impairment in mice was assessed using the passive avoidance test over 12 days. It was found that some galantamine derivatives administered in a dose of 1/20LD50 improved the memory in experimental mice, especially on days 5-12 of the experiment.

Bergapten Improves Scopolamine-Induced Memory Impairment in Mice via Cholinergic and Antioxidative Mechanisms.

Bergapten is a furanocoumarin naturally occurring in the Apiaceae family and it is a well-known photosensitizing agent used in photochemotherapy. In this study, we investigated the influence of bergapten on cognitive function and mechanism underlying these effects in scopolamine-induced memory impairment in male Swiss mice. The passive avoidance test was used to evaluate the efficiency of memory acquisition and consolidation. The results demonstrated that both single and repeated administration of bergapten improved not only the acquisition but also consolidation of memory. The behavioral tests showed that bergapten prevented memory impairment induced by administration of scopolamine. Observed effects may result from the inhibition of acetylcholinesterase activity in the hippocampus and prefrontal cortex. Also, bergapten caused significant anti-oxidative effects. These new findings provide pharmacological and biochemical support for the development of the coumarin’s potential in cognitive deficits.

Potentiation of anti-Alzheimer activity of curcumin by probiotic Lactobacillus rhamnosus UBLR-58 against scopolamine-induced memory impairment in mice.

Curcumin, a major component of Indian saffron through clinical studies, revealed its neuroprotective effect in neurodegenerative diseases. However, it has not been utilized alone orally due to its low bioavailability. There are certain strategies to overcome the drawbacks such as poor absorption and low aqueous solubility. Many strategies are utilized to increase the systemic availability of curcumin. Among them, the steady intestinal and liver metabolism of curcumin by a curcumin adjuvant (enzyme inhibitor/inducer) is an important and less engrossed strategy for improving the overall systemic bioavailability of curcumin. Here, we assess the effect of probiotic Lactobacillus rhamnosus as a curcumin adjuvant (potentiate the effect of curcumin) in scopolamine-induced dementia in mice. To induce amnesia, scopolamine was used in a mouse model (1 mg/kg, daily for 10 days i.p.). After execution of behavioural tests (Morris water maze test), brains and liver were isolated for further neurochemical and histopathology examination. Our results showed a significant increase in antioxidant enzyme levels in curcumin with a probiotic group compared with curcumin alone. Besides, histopathology study results showed less neuronal damage of curcumin with probiotics as compared with the curcumin and scopolamine alone groups. Additionally, curcumin with probiotics improved memory and cognitive functions in the behavioural study with the significance of p ≤ 0.0001. In conclusion, curcumin with probiotics has greater activity as compared with curcumin alone and reverses the hallmarks of Alzheimer's disease (AD).

Evaluation of neuroprotective and anti-amnesic effects of Elaeagnus umbellata Thunb. On scopolamine-induced memory impairment in mice

BackgroundElaeagnus umbellata is abundantly found in Himalayan regions of Pakistan which is traditionally used to treat various health disorders. However, the experimental evidence supporting the anti-amnesic effect is limited. Therefore the study was aimed to evaluate the prospective beneficial effect of E. umbellata on learning and memory in mice.ObjectivesTo assess neuroprotective and anti-amnesic effects of E. umbellata fruit extracts and isolated compounds on the central nervous system.MethodsMajor phytochemical groups present in methanolic extract of E. umbellata were qualitatively determined. The total phenolic and flavonoid contents were also determined in extract/fractions of E. umbellata. On the basis of in vitro promising anticholinesterases (AChE & BChE) and antioxidant activities observed for CHF. Ext and isolated compound-I (Chlorogenic acid = CGA), they were further evaluated for learning and memory in normal and scopolamine-induced cognitive impairment in mice using memory behavioral tests such as the Y maze and Novel object recognition using standard procedures. The test sample were further assessed for in vivo anticholinesterases (AChE & BChE) and DPPH free radical scavenging activities in mice brain sample and finally validated by molecular docking study using GOLD software.ResultsThe extract/fractions and isolated compounds were tested for their anticholinesterase and antioxidant potentials. The CHF. Ext and CGA showed maximum % inhibition of tested cholinesterases and free radicals. The CHF. Ext and CGA reversed the effects of scopolamine in mice. The CHF. Ext and CGA significantly increased the alternate arm returns and % spontaneous alteration performance while escape latency times (second) significantly decreased in Y maze test. The CHF. Ext and CGA significantly increased the time spent with novel object and also increased the discrimination index in the Novel object recognition test. Furthermore, molecular docking was used to validate the mechanism of cholinesterases inhibition of isolated compounds.ConclusionThe data obtained from behavioral and biochemical studies (AChE/BChE and DPPH/ABTS inhibition) have shown that E. umbellata possessed significant memory enhancing potency. These results suggest that E. umbellata extract possess potential antiamnesic effects and amongst the isolated compounds, compound I could be more effective anti-amnesic therapeutics. However, further studies are needed to identify the exact mechanism of action.Graphical abstract

Green tea extract containing enhanced levels of epimerized catechins attenuates scopolamine-induced memory impairment in mice

Ethnopharmacological relevanceGreen tea has been used as a traditional medicine to control brain function and digestion. Recent works suggest that drinking green tea could prevent cognitive function impairment. During tea manufacturing processes, such as brewing and sterilization, green tea catechins are epimerized. However, the effects of heat-epimerized catechins on cognitive function are still unknown. To take this advantage, we developed a new green tea extract, high temperature processed-green tea extract (HTP-GTE), which has a similar catechin composition to green tea beverages. Aim of the studyThis study aimed to investigate the effect of HTP-GTE on scopolamine-induced cognitive dysfunction and neuronal differentiation, and to elucidate its underlying mechanisms of action. Materials and methodsThe neuronal differentiation promoting effects of HTP-GTE in SH-SY5Y cells was assessed by evaluating neurite length and the expression level of synaptophysin. The DNA methylation status at the synaptophysin promoter was determined in differentiated SH-SY5Y cells and in the hippocampi of mice. HTP-GTE was administered for 10 days at doses of 30, 100 and 300 mg/kg (p.o.) to mice, and its effects on cognitive functions were measured by Y-maze and passive avoidance tests under scopolamine-induced cholinergic blockade state. ResultsHTP-GTE induced neuronal differentiation and neurite outgrowth via the upregulation of synaptophysin gene expression. These beneficial effects of HTP-GTE resulted from reducing DNA methylation levels at the synaptophysin promoter via the suppression of DNMT1 activity. The administration of HTP-GTE ameliorated cognitive impairments in a scopolamine-treated mouse model. ConclusionsThese results suggest that HTP-GTE could alleviate cognitive impairment by regulating synaptophysin expression and DNA methylation levels. Taken together, HTP-GTE would be a promising treatment for the cognitive impairment observed in dysfunction of the cholinergic neurotransmitter system.

Scopolamine 유발 기억 손상 마우스에서 익모초의 효과

Cognitive impairment is symptoms of dementia, a degenerative brain disease that is drawing attention in a rapidly aging society. This study was conducted to investigate the improvement of cognitive function of Leonurus japonicus on scopolamine-induced memory impairment in mice and the effect and mechanism of memory recovery. In vivo studies were conducted on mice orally pretreated with L. japonicus in doses of 50, 100 and 200 ㎎/㎏ (p.o.) and scopolamine (1 ㎎/㎏, i.p.) were injected 30 min before the behavioral task. Antioxidant activity was assessed by 2,2-diphenyl-1-picryl hydrazyl (DPPH) assay and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay, and acetylcholinesterase (AChE) inhibition activity evaluated by Ellman’s method. In behavior studies showed that L. japonicus has an improved the memory of scopolamine-treated mice in Y-maze, passive avoidance and Morris water maze test. In addition, L. japonicus was also exerted free radical scavenging activity and inhibited acetyl cholinesterase activity. These results suggest that L. japonicus improves short-term and long-term memory in scopolamine-induced memory decline model and prevents scopolamine-induced memory impairments through in reduced oxidative stress and acetyl cholinesterase inhibition effect. Thus, L. japonicus is related to functional medicinal materials for prevention and treatment of human dementia patients.

Protective Effects of Compounds from Cimicifuga dahurica against Amyloid Beta Production in Vitro and Scopolamine-Induced Memory Impairment in Vivo.

Cimicifuga dahurica has traditionally been used as an antipyretic, analgesic, and anti-inflammatory agent and as a treatment for uterine and anal prolapse. This study has investigated the potential beneficial effects of this medicinal plant and its components on Alzheimer's disease (AD) with a focus on amyloid beta (Aβ) production and scopolamine-induced memory impairment in mice. An ethanol extract from C. dahurica roots decreased Aβ production in APP-CHO cells [Chinese hamster ovarian (CHO) cells stably expressing amyloid precursor protein (APP)], as determined by an enzyme-linked immunosorbent assay and Western blot analysis. Then, the compounds isolated from C. dahurica were tested for their antiamyloidogenic activities. Four compounds (1-4) efficiently interrupted Aβ generation by suppressing the level of β-secretase in APP-CHO cells. Moreover, the in vivo experimental results demonstrated that compound 4 improved the cognitive performances of mice with scopolamine-induced disruption on behavioral tests and the expression of memory-related proteins. Taken together, these results suggest that C. dahurica and its constituents are potential agents for preventing or alleviating the symptoms of AD.

Dracocephalum moldavica attenuates scopolamine-induced cognitive impairment through activation of hippocampal ERK-CREB signaling in mice

Ethnopharmacological relevanceDracocephalum moldavica (Moldavian balm) has been traditionally used for the treatment of intellectual disabilities, migraines and cardiovascular problems in East Asia. Recent scientific studies have demonstrated the usefulness of this plant to treat neurodegenerative disorders, including Alzheimer's disease. Aim of the studyThis study aimed to investigate the effects of the ethanolic extract of D. moldavica leaves (EEDM) on scopolamine-induced cognitive impairment in mice and the underlying mechanisms of action. Materials and methodsThe behavioral effects of EEDM were examined using the step-through passive avoidance and Morris water maze tasks. To elucidate the underlying mechanism, we tested whether EEDM affects acetylcholinesterase activity and the expression of memory-related signaling molecules including extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB) in the hippocampus. ResultsEEDM (25, 50 or 100 mg/kg) significantly ameliorated the scopolamine-induced step-through latency reduction in the passive avoidance task in mice. In the Morris water maze task, EEDM (50 mg/kg) significantly attenuated scopolamine-induced memory impairment. Furthermore, the administration of EEDM increased the phosphorylation levels of ERK and CREB in the hippocampus but did not alter acetylcholinesterase activity. ConclusionsThese findings suggest that EEDM significantly attenuates scopolamine-induced memory impairment in mice and may be a promising therapeutic agent for improving memory impairment.

Cortico-Hippocampal Memory Enhancing Activity of Hesperetin on Scopolamine-Induced Amnesia in Mice: Role of Antioxidant Defense Systems, Cholinergic Neurotransmission and Expression of BDNF

Alzheimer disease (AD) is an age related neurodegenerative disease causing severe cognitive and memory decline in elderly people. Flavonoids play neuroprotective role by inhibiting and/or modifying the self-assembly of the amyloid-β (Aβ) or tau peptide into oligomers and fibrils. This study sought to investigate the effect of hesperetin (HPT) on scopolamine-induced memory impairments in mice. Mice were orally pretreated with HPT (1, 5 or 50 mg/kg) or vehicle (normal saline; 10 ml/kg) for 3 consecutive days. One hour post-treatment on day 3, scopolamine (3 mg/kg, i.p.) was administered 5 min before locomotor activity (open field test) and memory function (novel object recognition test (NORT) for 2 consecutive days and Morris water maze task (MWM) for 5 consecutive days). Levels of oxidative stress markers / brain derived neurotrophic factors (BDNF) and acetylcholinesterase activity were determined in the hippocampus and prefrontal cortex after completion of MWM task. Scopolamine caused no significant change in mice exploration of the familiar or novel object in the test session whereas the HPT-treated mice spent more time exploring the novel object more than familiar object in NORT. Scopolamine also increased the escape latency in acquisition phase and decreases time spent in target quadrant in probe phase which were ameliorated by the pretreatment with HPT. Scopolamine-induced alteration of oxidant-antioxidant balance, acetylcholinesterase activity and neurogenesis in the hippocampus and prefrontal cortex were attenuated by HPT treatment. This study showed that HPT ameliorated non-spatial/spatial learning and memory impairment by scopolamine possibly through enhancement of antioxidant defense, cholinergic and BDNF signaling.

Diastereomeric Mixture of Calophyllic and Isocalophyllic Acid Ameliorates Scopolamine-Induced Memory Impairment in Mice: Involvement of Antioxidant Defense and Cholinergic Systems.

Dementia of Alzheimer disease type (AD) and type 2 diabetes mellitus (T2D) are two most common diseases of aging which has reached epidemic proportions. Moreover, there is a shared mechanism of pathogenesis between metabolic disorders and AD. Hence, the need for discivery of effective prevention and treatment strategies. Diastereomeric mixture of calophyllic acid and isocalophyllic acid (ISO) has been shown to stimulate glucose uptake through GLUT4- translocation. In this study, an attempt was made to investigate the effect of ISO on scopolamine-induced memory deficit in mice. ISO (5, 25 or 50 mg/kg, p.o.) or vehicle (10 ml/kg, p.o.) was administered for 3 consecutive days. One hour post-treatment on day 3, scopolamine (3 mg/kg, i.p.) was given before the animals were subjected to Y-maze, open field, novel object recognition (NOR) or Morris water maze (MWM; 5 consecutive days) paradigms. The mice were sacrificed 45 min after MWM test on day 8. The hippocampus and prefrontal cortex were rapidly isolated on ice for assay of biochemical markers of oxidative stress and acetylcholinesterase activity. Scopolamine reduced the percentage alternation behaviour in the Y-maze and discrimination index in NOR tests with no significant change in escape latency time in MWM task suggestive of deficit in learning and memory. However, the pretreatment of mice with ISO produced a dose-dependent improvement in learning and memory. Moreover, ISO administration attenuated scopolamine-induced increase in malondialdehyde/nitrite generation and acetylcholinesterase activity and deficit in antioxidant enzyme activity in the hippocampus and prefrontal cortex. Findings from this study showed that the diastereomeric mixture of calophyllic acid and isocalophyllic acid possesses anti-amnesic effect through enhancement of antioxidant defense and cholinergic signaling pathway.

Mulberry Fruit Extract Prevents Against Scopolamine-Induced Memory Impairment in Mice

Mulberry Fruit Extract Prevents Against Scopolamine-Induced Memory Impairment in Mice

Fermented rice peptides attenuate scopolamine-induced memory impairment in mice by regulating neurotrophic signaling pathways in the hippocampus

This study investigated the preventive effects of fermented rice peptides (FRPs) against scopolamine-induced memory impairment in mice and their potential mechanisms. Mice were pretreated with FRPs (25 and 100 mg/kg body weight) via intraperitoneal injection for 7 days, followed by intraperitoneal injection of scopolamine. FRP pretreatment suppressed scopolamine-induced cognitive impairment in passive-avoidance test and significantly upregulated levels of brain-derived neurotrophic factor (BDNF) and induced the phosphorylation of cAMP response element binding (CREB) protein and extracellular signal-regulated kinase (ERK) in the hippocampus of scopolamine-treated mice. Additionally, scopolamine-treated mice showed significantly decreased acetylcholine levels and increased acetylcholine-esterase activity in the hippocampus as compared with controls; however, these changes were suppressed by FRP pretreatment. Among the fractions separated by size-exclusion chromatography, the non-glycosylated peptide fraction of FRP suppressed H2O2-induced neuronal damage in SK-N-SH cells via upregulated BDNF levels. Our findings demonstrated that FRP prevented memory impairment, and that the underlying mechanism might involve regulation of the ERK/CREB/BDNF signaling pathway. These results suggest FRP as a potential agent for the prevention of age-related cognitive decline and dementia.

Cortico-hippocampal memory enhancing activity of hesperetin on scopolamine-induced amnesia in mice: role of antioxidant defense system, cholinergic neurotransmission and expression of BDNF.

Alzheimer disease (AD) is an age related neurodegenerative disease causing severe cognitive and memory decline in elderly people. Flavonoids play neuroprotective role by inhibiting and/or modifying the self-assembly of the amyloid-β (Aβ) or tau peptide into oligomers and fibrils. This study sought to investigate the effect of hesperetin (HPT) on scopolamine-induced memory impairments in mice. Mice were orally pretreated with HPT (1, 5 or 50mg/kg) or vehicle (normal saline; 10ml/kg) for 3 consecutive days. One hour post-treatment on day 3, scopolamine (3mg/kg, i.p.) was administered 5min before locomotor activity (open field test) and memory function (novel object recognition test (NORT) for 2 consecutive days and Morris water maze task (MWM) for 5 consecutive days). Levels of oxidative stress markers / brain derived neurotrophic factors (BDNF) and acetylcholinesterase activity were determined in the hippocampus and prefrontal cortex after completion of MWM task. Scopolamine caused no significant change in mice exploration of the familiar or novel object in the test session whereas the HPT-treated mice spent more time exploring the novel object more than familiar object in NORT. Scopolamine also increased the escape latency in acquisition phase and decreases time spent in target quadrant in probe phase which were ameliorated by the pretreatment with HPT. Scopolamine-induced alteration of oxidant-antioxidant balance, acetylcholinesterase activity and neurogenesis in the hippocampus and prefrontal cortex were attenuated by HPT treatment. This study showed that HPT ameliorated non-spatial/spatial learning and memory impairment by scopolamine possibly through enhancement of antioxidant defense, cholinergic and BDNF signaling.

Sulforaphane-Enriched Broccoli Sprouts Pretreated by Pulsed Electric Fields Reduces Neuroinflammation and Ameliorates Scopolamine-Induced Amnesia in Mouse Brain through Its Antioxidant Ability via Nrf2-HO-1 Activation

Activated microglia-mediated neuroinflammation plays a key pathogenic role in neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and ischemia. Sulforaphane is an active compound produced after conversion of glucoraphanin by the myrosinase enzyme in broccoli (Brassica oleracea var) sprouts. Dietary broccoli extract as well as sulforaphane has previously known to mitigate inflammatory conditions in aged models involving microglial activation. Here, we produced sulforaphane-enriched broccoli sprouts through the pretreatment of pulsed electric fields in order to trigger the biological role of normal broccoli against lipopolysaccharide-activated microglia. The sulforaphane-enriched broccoli sprouts showed excellent potency against neuroinflammation conditions, as evidenced by its protective effects in both 6 and 24 h of microglial activation in vitro. We further postulated the underlying mechanism of action of sulforaphane in broccoli sprouts, which was the inhibition of an inflammatory cascade via the downregulation of mitogen-activated protein kinase (MAPK) signaling. Simultaneously, sulforaphane-enriched broccoli sprouts inhibited the LPS-induced activation of the NF-κB signaling pathway and the secretions of inflammatory proteins (iNOS, COX-2, TNF-α, IL-6, IL-1β, PGE2, etc.), which are responsible for the inflammatory cascades in both acute and chronic inflammation. It also upregulated the expression of Nrf2 and HO-1 in normal and activated microglia followed by the lowered neuronal apoptosis induced by activated microglia. Based on these results, it may exhibit anti-inflammatory effects via the NF-κB and Nrf2 pathways. Interestingly, sulforaphane-enriched broccoli sprouts improved the scopolamine-induced memory impairment in mice through Nrf2 activation, inhibiting neuronal apoptosis particularly through inhibition of caspase-3 activation which could lead to the neuroprotection against neurodegenerative disorders. The present study suggests that sulforaphane-enriched broccoli sprouts might be a potential nutraceutical with antineuroinflammatory and neuroprotective activities.