Mouse Exploratory Behaviour in the Open Field with and without NAT-1 EEG Device: Effects of MK801 and Scopolamine.

One aspect of reproducibility in preclinical research that is frequently overlooked is the physical condition in which physiological, pharmacological, or behavioural recordings are conducted. In this study, the physical conditions of mice were altered through the attachments of wireless electrophysiological recording devices (Neural Activity Tracker-1, NAT-1). NAT-1 devices are miniaturised multichannel devices with onboard memory for direct high-resolution recording of brain activity for >48 h. Such devices may limit the mobility of animals and affect their behavioural performance due to the added weight (total weight of approximately 3.4 g). The mice were additionally treated with saline (control), N-methyl-D-aspartate (NMDA) receptor antagonist MK801 (0.85 mg/kg), or the muscarinic acetylcholine receptor blocker scopolamine (0.65 mg/kg) to allow exploration of the effect of NAT-1 attachments in pharmacologically treated mice. We found only minimal differences in behavioural outcomes with NAT-1 attachments in standard parameters of locomotor activity widely reported for the open field test between the drug treatments. Hypoactivity was globally observed as a consistent outcome in the MK801-treated mice and hyperactivity in scopolamine groups regardless of NAT-1 attachments. These data collectively confirm the reproducibility for combined behavioural, pharmacological, and physiological endpoints even in the presence of lightweight wireless data loggers. The NAT-1 therefore constitutes a pertinent tool for investigating brain activity in, e.g., drug discovery and models of neuropsychiatric and/or neurodegenerative diseases with minimal effects on pharmacological and behavioural outcomes.

Mass spectrometry (MS)-based metabolomics of plasma and urine in dry eye disease (DED)-induced rat model.

Dry eye disease (DED) is an ophthalmic disease associated with poor quality and quantity of tears, and the number of patients is steadily increasing. The aim of this study was to determine plasma and urine metabolites obtained from DED scopolamine animal model where dry eye conditions (DRY) are induced. It was also of interest to examine whether DED (scopolamine) rat model was exacerbated by treatment with benzalkonium chloride (BAC). Subsequently, plasma and urine metabolites were analyzed using liquid chromatography (LC) and gas chromatography (GC)-mass spectrometry (MS), respectively. Data demonstrated that DED indicators such as tear volume, tear breakup time (TBUT), and corneal damage in the DED groups (DRY and BAC group) differed from those of control (CON). Similar results were noted in inflammatory factors such as interleukin (IL-1ß), IL-6, and tumor necrosis factor (TNF)-α. In the partial least squares-discriminant analysis (PLS-DA) score plots, the three groups were distinctly separated from each other. In addition, the related metabolites were also associated with these distinct separations as evidenced by 9 and 14 in plasma and urine, respectively. Almost all of the selected metabolites were decreased in the DRY group compared to CON, and the BAC group was lower than the DRY. In plasma and urine, lysophosphatidylcholine/lysophosphatidylethanolamine, organic acids, amino acids, and sugars varied between three groups, and these metabolites were related to inflammation and oxidative stress. Data suggest that treatment with scopolamine with/without BAC-induced DED and affected the level of systemic metabolites involved in inflammation and oxidative stress.

Effects of extracts and manna of Echinops cephalotes on impaired cognitive function induced by scopolamine in mice.

Background and purpose: Alzheimer's disease (AD) is a neurodegenerative disease specified by chronic and irreversible destruction of neurons. This study aimed to evaluate the effects of different extracts (aqueous, hydroalcoholic, hexane, and ethyl acetate) and manna of Echinops cephalotes (EC) on impaired cognitive function induced by scopolamine in mice. EC is shown to have anti-cholinesterase-butyrylcholinesterase activities. Experimental approach: In this study, aqueous and hydroalcoholic extracts, hexane and ethyl acetate fractions of EC (25, 50, 100 mg/kg, i.p.), and the manna (25, 50, 100 mg/kg, gavage) were administered for 14 days alongside scopolamine (0.7 mg/kg, i.p.). Rivastigmine (reference drug) was administered for 2 weeks i.p. Mice were tested for their memory function using two behavioral models, object recognition test (ORT) and passive avoidance test (PAT). Findings/Results: Administration of scopolamine significantly impaired memory function in both behavioral models. In the PAT model, all extracts at 50 and 100 mg/kg significantly reversed the effect of memory destruction caused by scopolamine. At a lower dose of 25 mg/kg, however, none of the extracts were able to significantly change the step-through latency time. In the ORT model, however, administration of all extracts at 50 and 100 mg/kg, significantly increased the recognition index. Only the manna and the aqueous extract at 25 mg/kg were able to reverse scopolamine-induced memory impairment. Conclusions and implications: These results suggest that all forms of EC extracts improve memory impairment induced by scopolamine comparably to rivastigmine. Whether the effects are sustained over a longer period remains to be tested in future work.

Subchronic administration of scopolamine reverses UCMS-induced behavior in mice via eEF2 protein dephosphorylation.

BACKGROUND: The cholinergic system has been increasingly linked to the pathophysiology of mood disorders such as depression, with the potential involvement of nicotinic and/or muscarinic receptors. Conventional antidepressants usually require weeks of daily dosing to achieve a full antidepressant response. In contrast, clinical studies have shown that scopolamine, a nonselective muscarinic acetylcholine receptor antagonist, can induce potent and rapid antidepressant effects, requiring only a few days of treatment. This study aimed to examine the suitability of the unpredictable chronic mild stress (UCMS) model of depression to reproduce the above scopolamine antidepressant activity patterns. METHODS: Rapid and sustained antidepressant-like effects were assessed by using the splash test, sucrose preference test (SPT), tail suspension test (TST), and forced swimming test (FST) in animals undergoing the UCMS procedure and stress-naïve C57BL/6J mice. Western Blotting was used to measure tropomyosin receptor kinase B (TrkB), mammalian target of rapamycin (mTOR), eukaryotic elongation factor (eEF2) and postsynaptic density protein 95 (PSD95) levels. RESULTS: Scopolamine induced antidepressant-like effects in a dose-dependent manner only after subchronic, but not single, administration in the UCMS model of depression in C57BL/6J mice without affecting locomotor activity. Specifically, scopolamine administered at a dose of 0.3 mg/kg for four consecutive days significantly reversed the UCMS-induced depressive-like behavior, such as apathy, anhedonia, and behavioral despair, while scopolamine, given at the same dose but only once, did not relieve the above symptoms. Scopolamine treatment was accompanied by eEF2 protein dephosphorylation and its subsequent reactivation in the prefrontal cortex (PFC). CONCLUSION: Subchronic administration of scopolamine is needed to ameliorate UCMS-induced depressive-like behavior. The suggested mechanism of scopolamine action covers eEF2 protein activity in the PFC.

Melatonin attenuates scopolamine-induced cognitive dysfunction through SIRT1/IRE1α/XBP1 pathway.

BACKGROUND: The prevalence of dementia around the world is increasing, and these patients are more likely to have cognitive impairments, mood and anxiety disorders (depression, anxiety, and panic disorder), and attention deficit disorders over their lifetime. Previous studies have proven that melatonin could improve memory loss, but its specific mechanism is still confused. METHODS: In this study, we used in vivo and in vitro models to examine the neuroprotective effect of melatonin on scopolamine (SCOP)-induced cognitive dysfunction. The behavioral tests were performed. 18F-FDG PET imaging was used to assess the metabolism of the brain. Protein expressions were determined through kit detection, Western blot, and immunofluorescence. Nissl staining was conducted to reflect neurodegeneration. MTT assay and RNAi transfection were applied to perform the in vitro experiments. RESULTS: We found that melatonin could ameliorate SCOP-induced cognitive dysfunction and relieve anxious-like behaviors or HT22 cell damage. 18F-FDG PET-CT results showed that melatonin could improve cerebral glucose uptake in SCOP-treated mice. Melatonin restored the cholinergic function, increased the expressions of neurotrophic factors, and ameliorated oxidative stress in the brain of SCOP-treated mice. In addition, melatonin upregulated the expression of silent information regulator 1 (SIRT1), which further relieved endoplasmic reticulum (ER) stress by decreasing the expression of phosphorylate inositol-requiring enzyme (p-IRE1α) and its downstream, X-box binding protein 1 (XBP1). CONCLUSIONS: These results indicated that melatonin could ameliorate SCOP-induced cognitive dysfunction through the SIRT1/IRE1α/XBP1 pathway. SIRT1 might be the critical target of melatonin in the treatment of dementia.

Concomitant administration of resveratrol and resistance training ameliorates acrylamide-induced spatial learning impairment in rats.

Objective: The present study examined effects of resistance training (RT) and resveratrol (RES) alone and together on acrylamide (AC)-induced memory impairment in rats. Materials and Methods: Animals were divided into 6 groups: (1) Control group which received normal saline intraperitoneally (ip) daily for 8 weeks; (2) Scopolamine (SCO) group which received SCO (1 mg/kg/day, ip) for 8 weeks; (3) AC group which received AC (5 mg/kg/day, ip) for 8 weeks; (4) AC + RT group which received AC (5 mg/kg/day, ip) for 8 weeks and performed RT (5 days a week for 8 weeks); (5) AC + RES group which received AC (5 mg/kg/day, ip) and RES (1 mg/kg/day, ip) for 8 weeks; and (6) AC + RT + RES group which received AC (5 mg/kg/day, ip) and RES (1 mg/kg/day, ip) for 8 weeks and performed RT (5 days a week for 8 weeks). On day 53, animal training began in the Morris Water Maze (MWM) and 24 hr after the last training, the probe test was performed. Results: RT and RES alone did not significantly affect escape latency or traveled distance increased by AC. However, concomitant RES and RT treatment significantly reduced these parameters compared to the AC group. Co-treatment with RES and RT also significantly increased the time spent in the target quadrant compared to the AC group. Lipid peroxidation was reduced in the AC+RES and AC+RT+RES groups compared to the AC group. Conclusion: It seems that daily co-treatment with RES and RT for 8 weeks ameliorates the memory-impairing effects of AC.

Neuroprotective Effects of Dehydroepiandrosterone and Hericium erinaceus in Scopolamine-induced Alzheimer's Diseases-like Symptoms in Male Rats.

BACKGROUND: The neuroprotective effects of Dehydroepiandrosterone (DHEA) and Hericium erinaceus (H. erinaceus) mushroom extract against scopolamine-induced Alzheimer's disease-like symptoms in male Wistar rats were investigated. METHODS: Sixty-four male Wistar rats were divided into eight groups (n = 8). Scopolamine (SCO) was intraperitoneally injected at a dose of 1 mg/kg/day for 10 days. The treatment groups orally received DHEA (250 mg/kg/day) and/or H. erinaceus (300 mg/kg/day) for 14 days. Afterward, the Morris water maze (MWM) and novel object recognition tests were implemented. Then, animals were anesthetized and the brain tissue samples were separated. Levels of lipid peroxidation (LPO), total antioxidant capacity (TAC), catalase activity (CAT), and brain-derived neurotrophic factor (BDNF) were determined. Also, histopathological studies were evaluated in the brain tissue samples. RESULTS: Administration of SCO significantly decreased spatial and cognitive memory (p < 0.001). Not only did SCO injection significantly increase the levels of the LPO but also the SCO markedly reduced the levels of the TAC, CAT activity, and the BDNF in the brain tissue. On the other hand, a combination of the DHEA and H. erinaceus showed higher efficacy than the DHEA or H. erinaceus in attenuating behavioral anomalies and improving the antioxidant defense system and BDNF levels. Histological examination was well correlated with biochemical findings regarding SCO neurodegeneration and DHEA and/or H. erinaceus neuroprotection. CONCLUSION: Interestingly, ADHE and/or H. erinaceus may due to their potential neurotrophic properties be used as a new and beneficial concurrent therapy in the treatment of Alzheimer's disease-like symptoms caused by SCO.

Evaluation of the mechanism of action of paracetamol, drotaverine, and peppermint oil and their effects in combination with hyoscine butylbromide on colonic motility: human ex-vivo study.

Introduction: Drotaverine, paracetamol, and peppermint oil are often prescribed for the treatment of gastrointestinal spasm and pain. This study aimed to evaluate the effect of these drugs alone and combined with the well-known antispasmodic hyoscine butylbromide on the human colon. Methods: Colon samples were obtained from macroscopically normal regions of 68 patients undergoing surgery and studied in muscle bath. Drotaverine, paracetamol, and peppermint oil were tested alone and in combination with hyoscine butylbromide on (1) spontaneous contractility induced by isometric stretch (in the presence of 1 µM tetrodotoxin) and (2) contractility induced by 10-5 M carbachol and after (3) electrical field stimulation-induced selective stimulation of excitatory (in the presence of 1 mM Nω-nitro-L-arginine and 10 µM MRS2179) and (4) inhibitory (under non-adrenergic, non-cholinergic conditions) pathways. (5) Drotaverine alone was also tested on cAMP-dependent pathway activated by forskolin. Results: Compared with the vehicle, drotaverine and paracetamol (10-9-10-5 M) did not modify spontaneous contractions, carbachol-induced contractions, and responses attributed to selective activation of excitatory pathways. The addition of hyoscine butylbromide (10-7-10-5 M), concentration-dependently reduced myogenic contractions and carbachol- and electrical field stimulation-induced contractile responses. The association of paracetamol (10-4 M) and hyoscine butylbromide (10-7-10-5 M) was not different from hyoscine butylbromide alone (10-7-10-5 M). At higher concentrations (10-3M-3*10-3 M), paracetamol decreased myogenic and carbachol-induced contractions. The adenylate cyclase activator, forskolin, concentration-dependently reduced contractility, leading to smooth muscle relaxation. The effect of forskolin 10-7 M was concentration-dependently enhanced by drotaverine (10-6M-10-5M). Discussion: Peppermint oil reduced myogenic activity and carbachol- and electrical field stimulation-induced contractions. The association of hyoscine butylbromide and peppermint oil was synergistic since the interaction index measured with the isobologram was lower than 1. No effect was seen on the neural-mediated inhibitory responses with any of the drugs studied although peppermint oil reduced the subsequent off-contraction. Drotaverine and hyoscine butylbromide have a complementary effect on human colon motility as one stimulates the cAMP inhibitory pathway and the other inhibits the excitatory pathway. Peppermint oil is synergic with hyoscine butylbromide suggesting that a combination therapy may be more effective in treating patients. In contrast, at therapeutic concentrations, paracetamol does not modify colonic contractility, suggesting that the association of paracetamol and hyoscine butylbromide has independent analgesic and antispasmodic properties.

An Overview of the Natural Neuroprotective Agents for the Management of Cognitive Impairment Induced by Scopolamine in Zebrafish (Danio rerio).

Alzheimer's Disease (AD) is a neurodegenerative disorder mainly characterized by dementia and cognitive decline. AD is essentially associated with the presence of aggregates of the amyloid-ß peptide and the hyperphosphorylated microtubule-associated protein tau. The available AD therapies can only alleviate the symptoms; therefore, the development of natural treatments that exhibit neuroprotective effects and correct the behavioral impairment is a critical requirement. The present review aims to collect the natural substances that have been evaluated for their neuroprotective profile against AD-like behaviors induced in zebrafish (Danio rerio) by scopolamine. We focused on articles retrieved from the PubMed database via preset searching strings from 2010 to 2023. Our review assembled 21 studies that elucidated the activities of 28 various natural substances, including bioactive compounds, extracts, fractions, commercial compounds, and essential oils. The listed compounds enhanced cognition and showed several mechanisms of action, namely antioxidant potential, acetylcholinesterase's inhibition, and reduction of lipid peroxidation. Additional studies should be achieved to demonstrate their preventive and therapeutic activities in cellular and rodent models. Further clinical trials would be extremely solicited to support more insight into the neuroprotective effects of the most promising drugs in an AD context.

Alleviative effect of scopolamine­induced memory deficit via enhancing antioxidant and cholinergic function in rats by pinostrobin from Boesenbergia rotunda (L.).

Pinostrobin, a key bioactive compound found in the medicinal plant Boesenbergia rotunda (L.), has been noted for its beneficial biological properties including antioxidant, anti-inflammation, anti-cancer and anti-amnesia activities. In view of this, the present study purposed to evaluate the neuroprotective potential of pinostrobin in reversing scopolamine-induced cognitive impairment involving oxidative stress and cholinergic function in rats. A total of 30 male Wistar rats were randomly divided into five groups (n=6): Group 1 received vehicle as a control, group 2 received vehicle + scopolamine (3 mg/kg, i.p.), group 3 received pinostrobin (20 mg/kg, p.o.) + scopolamine, group 4 received pinostrobin (40 mg/kg, p.o.) + scopolamine and group 5 received donepezil (5 mg/kg, p.o.) + scopolamine. Treatments were administered orally to the rats for 14 days. During the final 7 days of treatment, a daily injection of scopolamine was administered. Scopolamine impaired learning and memory performance, as measured by the novel object recognition test and the Y-maze test. Additionally, oxidative stress marker levels, acetylcholinesterase (AChE) activity, choline acetyltransferase (ChAT) and glutamate receptor 1 (GluR1) expression were determined. Consequently, the findings demonstrated that the administration of pinostrobin (20 and 40 mg/kg) markedly improved cognitive function as indicated by an increase in recognition index and by spontaneous alternation behaviour. Pinostrobin also modulated the levels of oxidative stress by causing a decrease in malondialdehyde levels accompanied by increases in superoxide dismutase and glutathione activities. Similarly, pinostrobin markedly enhanced cholinergic function by decreasing AChE activity and promoting ChAT immunoreactivity in the hippocampus. Additionally, the reduction in GluR1 expression due to scopolamine was diminished by treatment with pinostrobin. The findings indicated that pinostrobin exhibited a significant restoration of scopolamine-induced memory impairment by regulating oxidative stress and cholinergic system function. Thus, pinostrobin could serve as a potential therapeutic agent for the management of neurodegenerative diseases such as Alzheimer's disease.

Ameliorative effect of vanillic acid against scopolamine-induced learning and memory impairment in rat via attenuation of oxidative stress and dysfunctional synaptic plasticity.

Alzheimer's disease (AD) is characterized by cognitive impairment, loss of learning and memory, and abnormal behaviors. Scopolamine (SCOP) is a non-selective antagonist of muscarinic acetylcholine receptors that exhibits the behavioral and molecular hallmarks of AD. Vanillic acid (VA), a phenolic compound, is obtained from the roots of a traditional plant called Angelica sinensis, and has several pharmacologic effects, including antimicrobial, anti-inflammatory, anti-angiogenic, anti-metastatic, and antioxidant properties. Nevertheless, VA's neuroprotective potential associated with the memory has not been thoroughly investigated. Therefore, this study investigated whether VA treatment has an ameliorative effect on the learning and memory impairment induced by SCOP in rats. Behavioral experiments were utilized to assess the learning and memory performance associated with the hippocampus. Using western blotting analysis and assay kits, the neuronal damage, oxidative stress, and acetylcholinesterase activity responses of hippocampus were evaluated. Additionally, the measurement of long-term potentiation was used to determine the function of synaptic plasticity in organotypic hippocampal slice cultures. In addition, the synaptic vesicles' density and the length and width of the postsynaptic density were evaluated using electron microscopy. Consequently, the behavioral, biochemical, electrophysiological, and ultrastructural analyses revealed that VA treatment prevents learning and memory impairments caused by SCOP in rats. The study's findings suggest that VA has a neuroprotective effect on SCOP-induced learning and memory impairment linked to the hippocampal cholinergic system, oxidative damage, and synaptic plasticity. Therefore, VA may be a prospective therapeutic agent for treating AD.

Investigating the Potential of Essential Oils from Citrus reticulata Leaves in Mitigating Memory Decline and Oxidative Stress in the Scopolamine-Treated Zebrafish Model.

Petitgrain essential oil (PGEO) is derived from the water distillation process on mandarin (Citrus reticulata) leaves. The chemical constituents of PGEO were analyzed by gas chromatography/mass spectrometry (GC/MS) method which revealed the presence of six compounds (100%). The major peaks were for methyl-N-methyl anthranilate (89.93%) and γ-terpinene (6.25%). Over 19 days, zebrafish (Tubingen strain) received PGEO (25, 150, and 300 µL/L) before induction of cognitive impairment with scopolamine immersion (SCOP, 100 µM). Anxiety-like behavior and memory of the zebrafish were assessed by a novel tank diving test (NTT), Y-maze test, and novel object recognition test (NOR). Additionally, the activity of acetylcholinesterase (AChE) and the extent of the brain's oxidative stress were explored. In conjunction, in silico forecasts were used to determine the pharmacokinetic properties of the principal compounds discovered in PGEO, employing platforms such as SwissADME, Molininspiration, and pKCSM. The findings provided evidence that PGEO possesses the capability to enhance memory by AChE inhibition, alleviate SCOP-induced anxiety during behavioral tasks, and diminish brain oxidative stress.

The Influence of an Acute Administration of Cannabidiol or Rivastigmine, Alone and in Combination, on Scopolamine-Provoked Memory Impairment in the Passive Avoidance Test in Mice.

Memory is one of the most important abilities of our brain. The process of memory and learning is necessary for the proper existence of humans in the surrounding environment. However, sometimes there are unfavourable changes in the functioning of the brain and memory deficits occur, which may be associated with various diseases. Disturbances in the cholinergic system lead to abnormalities in memory functioning and are an essential part of clinical symptoms of many neurodegenerative diseases. However, their treatment is difficult and still unsatisfactory; thus, it is necessary to search for new drugs and their targets, being an alternative method of mono- or polypharmacotherapy. One of the possible strategies for the modulation of memory-related cognitive disorders is connected with the endocannabinoid system (ECS). The aim of the present study was to determine for the first time the effect of administration of natural cannabinoid compound (cannabidiol, CBD) and rivastigmine alone and in combination on the memory disorders connected with cholinergic dysfunctions in mice, provoked by using an antagonist of muscarinic cholinergic receptor-scopolamine. To assess and understand the memory-related effects in animals, we used the passive avoidance (PA) test, commonly used to examine the different stages of memory. An acute administration of CBD (1 mg/kg) or rivastigmine (0.5 mg/kg) significantly affected changes in scopolamine-induced disturbances in three different memory stages (acquisition, consolidation, and retrieval). Interestingly, co-administration of CBD (1 mg/kg) and rivastigmine (0.5 mg/kg) also attenuated memory impairment provoked by scopolamine (1 mg/kg) injection in the PA test in mice, but at a much greater extent than administered alone. The combination therapy of these two compounds, CBD and rivastigmine, appears to be more beneficial than substances administered alone in reducing scopolamine-induced cognitive impairment. This polytherapy seems to be favourable in the pharmacotherapy of various cognitive disorders, especially those in which cholinergic pathways are implicated.

Sick of Feeling Sick: Management of Opioid Treatment-Induced Refractory Nausea Resulting in Suicidal Ideations With a Plan and Intent.

In this case report, we present the case of a 60-year-old Caucasian male with a history of depression, anxiety, opioid dependence, and idiopathic polyneuropathy, admitted to an inpatient psychiatric unit for suicidal ideation. The patient's symptoms were characterized by months of intractable nausea, severe anxiety, suicidal ideation (SI), and significant unintentional weight loss in the context of methadone-assisted treatment. Over nine days in the hospital, a treatment strategy was developed and refined, which eventually achieved sustained relief from nausea and significant improvement in anxiety. The most effective pharmacological interventions included mirtazapine, scopolamine, and gabapentin.

Memory enhancing and neuroprotective effects of apomorphine in a rat model of dementia.

Oxidative stress from generation of increased reactive oxygen species or has been reported to play an important role in dementia. Oxidative stress due to free radicals of oxygen or reactive oxygen species could be precipitating factors in the etiology of dementia. Apomorphine has been reported to have neuroprotective effects. To monitor memory enhancing and neuroprotective effects of apomorphine, we determined the antioxidant enzymes activities, lipid peroxidation, acetylcholine esterase (AChE) activity in brain and plasma, following repetitive administration of apomorphine in rat model of dementia. Biogenic amine levels were also monitored in hippocampus. Repeated administration of scopolamine was taken as an animal model of dementia. Decreased glutathione peroxidase, superoxide dismutase and catalase activities were observed in these animal models of dementia. While increased lipid peroxidation was also observed in the brain and plasma samples. The results showed significant effects of apomorphine. The activities of antioxidant enzymes displayed increased activities in both brain and plasma. Glutathione peroxidase and catalase activities were found to be significantly higher in brain and plasma of apomorphine treated rats. Superoxide dismutase (SOD) was significantly decreased in plasma of scopolamine injected rats; and a decreased tendency (non-significant) of SOD in brain was also observed. AChE activity in brain and plasma was significantly decreased in scopolamine treated rats. Learning and memory of rats in the present study was assessed by Morris Water Maze (MWM). Short-term memory and long-term memory was impaired significantly in scopolamine treated rats, which was prevented by apomorphine. Moreover, a marked decrease in biogenic amines was also found in the brain of scopolamine treated rats and was reverted in apomorphine treated rats. Results showed that scopolamine-treatment induced memory impairment and induced oxidative stress in rats as compared to saline-treated controls. These impairments were significantly restored by apomorphine administration. In conclusion, our data suggests that apomorphine at the dose of 1 mg/kg could be a potential therapeutic agent to treat dementia and related disorders.

Effect of pH and temperature on tropane alkaloids within a processing strategy to provide safe infant cereal-based food.

Tropane alkaloids (TAs) are secondary metabolites from weeds that can contaminate cereals and vegetables during harvest. Due to their toxicity, the Regulation (EC) 2023/915 sets maximum levels for atropine and scopolamine in cereal-based foods for infants containing millet, sorghum, buckwheat or their derived products. The aim of this study was to evaluate the effect of pH and temperature on the stability of TAs, as possible parameters in thermal processing to mitigate this chemical hazard in cereal-based infant food. The effect of pH (4 and 7) and temperature (80 °C and 100 °C) was assessed in buffer solutions. Also, treatment at 180 °C was performed in spiked and naturally incurred millet flour to assess the effect of high temperature, simulating cooking or drying, on the stability of TAs in the cereal matrix. The fate of 24 TAs was assessed by UHPLC-MS/MS. TAs showed high thermostability, although it was variable depending on the specific compound, pH, temperature and treatment time. In buffer solutions, higher degradation was found at 100 °C and pH 7. In spiked millet flour at 180 °C for 10 min, scopolamine and atropine contents decreased by 25 % and 22 %, similarly to other TAs which also showed a slow thermal degradation. Atropine, scopolamine, anisodamine, norscopolamine, scopine and scopoline were found in naturally contaminated millet flour. Interestingly, naturally incurred atropine was more thermostable than when spiked, showing a protective effect of the cereal matrix on TAs degradation. The present results highlight the need for an accurate monitorization of TAs in raw materials, as this chemical hazard may remain in infant cereal-based food even after intense thermal processing.

A Rabbit Dry Eye Model Induced by Subcutaneous Scopolamine.

PURPOSE: To establish and characterize a dry eye model in New Zealand rabbits by subcutaneous injections of scopolamine hydrobromide (SCOP). METHODS: Twenty New Zealand male rabbits were injected subcutaneously SCOP for 14 consecutive days; subcutaneous saline was used as a negative control. The correlated clinical parameters of ocular surface dryness were detected in vivo using tear secretion and corneal fluorescein staining. The expression of IL-1ß and TNF-α on the ocular surface and in lacrimal glands were analyzed by real-time PCR and western blot on the 14th day. The expression of Mucin-5 subtype AC (MUC5AC) was detected by Immunofluorescence staining in conjunctival tissue. RESULTS: The SCOP-treated rabbits exhibited significantly decreased aqueous tear secretion and increased corneal fluorescein staining scores over time. Both the mRNA expression levels and the protein expression levels of IL-1ß and TNF-α were significantly increased after SCOP treatment compared with those after saline treatment. The loss of conjunctival MUC5AC was found in the SCOP-injected rabbits. Some infiltrated inflammatory cells and atrophic acinar cells were observed in the lacrimal gland after SCOP treatment. The disordered structures of the ocular surface and lacrimal glands were also observed. CONCLUSIONS: This study showed that repeated subcutaneous SCOP injections successfully elicited some of the typical dry eye symptoms commonly seen in humans.

Walnut-Derived Peptides Ameliorate Scopolamine-Induced Memory Impairments in a Mouse Model via Activation of Peroxisome Proliferator-Activated Receptor γ-Mediated Excitotoxicity.

We investigated the protective effect of walnut peptides and YVPFPLP (YP-7) on scopolamine-induced memory impairment in mice and ß-amyloid (Aß)-induced excitotoxic injury in primary hippocampal neurons, respectively. Additionally, the protective mechanism of YP-7 on neuronal excitotoxicity was explored. Mouse behavioral and hippocampal slice morphology experiments indicate that YP-7 improves the learning and memory abilities of cognitively impaired mice and protects synaptic integrity. Immunofluorescence, western blotting, and electrophysiological experiments on primary hippocampal neurons indicate that YP-7 inhibits neuronal damage caused by excessive excitation of neurons induced by Aß. HT-22 cell treatment with peroxisome proliferator-activated receptor γ (PPARγ) activators and inhibitors showed that YP-7 activates PPARγ expression and maintains normal neuronal function by forming stable complexes with PPARγ to inhibit the extracellular regulated protein kinase pathway. Therefore, YP-7 can ameliorate glutamate-induced excitotoxicity and maintain neuronal signaling. This provides a theoretical basis for active peptides to ameliorate excitotoxicity and the development of functional foods.

Quercetin ameliorates cognitive deficit, expression of amyloid precursor gene, and pro-inflammatory cytokines in an experimental models of Alzheimer's disease in Wistar rats.

Chronic stress (CS) is critically involved in the Alzheimer's disease (AD) pathogenesis resulting in cognitive disturbance. Also, amyloid precursor protein (APP) related gens, pro-inflammatory cytokines, and stress increases AD-related pathogenesis through increasing APP, all are important players in the development of AD. Herein, we explore the possible neuroprotective and anti-amnestic effect of quercetin (QUER) on cognitive deficits induced by scopolamine (SCOP) in stressed rats. Stress induction was performed by exposed of rats to 2-h chronic restraint stress for 10 days. Then rats were supplemented with QUER (25 mg/kg/day oral gavage, for 1 month). Ratswere submitted to intraperitoneal (i.p.) injection of SCOP (1 mg/kg) during the final 9 days of QUER supplementation to induce dementia like condition. Following the interventions, behavioral tests [elevated plus maze (EPM) and novel object recognition memory (NORM)] was examined to analysis the cognitive functions. Meanwhile, prefrontal cortex (PFC) and hippocampus of brain were used for gene expression and biochemical studies. Also, the plasma corticosterone (CORT) level was measured. We established that administration of QUER ameliorated the SCOP-related memory impairment. Also, QUER decreased stress related anxiety like behaviors in the EPM. QUER also altered the interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels in both PFC and hippocampus of SCOP treated rats in stress and non-stress conditions. We found that QUER increased APP and amyloid precursor-like protein 2 (APLP2) mRNA expression in both non-stress and stressed rats. Also, our findings imply that QUER suppress the effect of SCOP on cognitive functions. Moreover, decreased APP mRNA expression in the hippocampus were observed following pretreatment of rats with QUER in both stress and non-stress groups. Given that decreased amyloid beta (Aß) expression in the hippocampus of stressed rats, it can be proposed that elevations in APP mRNA expression by QUER activates non-amyloidogenic pathways leading to reduction in Aß levels. However, our findings indicate that QUER can be a therapeutic candidate, which exerts an anti-amnesic property against SCOP-induced memory decline. On the other hand, prior QUER administration in stress condition could be a promising approach against AD prevention.

A Comprehensive Description of the Anatomy and Histochemistry of Psychotria capillacea (Müll. Arg.) Standl. and an Investigation into Its Anti-Inflammatory Effects in Mice and Role in Scopolamine-Induced Memory Impairment.

Species of the genus Psychotria are used in popular medicine for pain, inflammatory symptoms, and mental disorders. Psychotria capillacea (Müll. Arg.) Standl. (Rubiaceae) is commonly known as coffee and some scientific studies have demonstrated its therapeutic potential. The goal of this study was to investigate the anti-inflammatory and neuroprotective effects, and acetylcholinesterase (AChE) inhibitory activity of a methanolic extract obtained from leaves of P. capillacea (MEPC), as well as the micromorphology and histochemistry of the leaves and stems of this plant. In addition, the MEPC was analyzed by UHPLC-MS/MS and the alkaloidal fraction (AF) obtained from the MEPC was tested in a mouse model of inflammation. MEPC contained three indole alkaloids, one sesquiterpene (megastigmane-type) and two terpene lactones. MEPC (3, 30 and 100 mg/kg) and AF (3 and 30 mg/kg) were evaluated in inflammation models and significantly inhibited edema at 2 h and 4 h, mechanical hyperalgesia after 4 h and the response to cold 3 h and 4 h after carrageenan injection. Scopolamine significantly increased the escape latency, and reduced the swimming time and number of crossings in the target quadrant and distance, while MEPC (3, 30 and 100 mg/kg), due to its neuroprotective actions, reversed these effects. AChE activity was significantly decreased in the cerebral cortex (52 ± 3%) and hippocampus (60 ± 3%), after MEPC administration. Moreover, micromorphological and histochemical information was presented, to aid in species identification and quality control of P. capillacea. The results of this study demonstrated that P. capillacea is an anti-inflammatory and antihyperalgesic agent that can treat acute disease and enhance memory functions in mouse models.