Protective effect of a hydromethanolic extract from Fraxinus excelsior L. bark against a rat model of aluminum chloride-induced Alzheimer's disease: Relevance to its anti-inflammatory and antioxidant effects.

ETHNOPHARMACOLOGICAL RELEVANCE: Fraxinus excelsior L. (FE), commonly known as the ash, belongs to the Oleaceae family and has shown several pharmacological and biological properties, such as antioxidant, immunomodulatory, neuroprotective, and anti-inflammatory effects. It has also attracted the most attention toward neuroinflammation. Moreover, FE bark and leaves have been used to treat neurological disorders, aging, neuropathic pain, urinary complaints, and articular pain in traditional and ethnomedicine. Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder resulting from the involvement of amyloid-beta, metal-induced oxidative stress, and neuroinflammation. AIM OF THE STUDY: The objective of the current study was to assess the neuroprotective effects of hydromethanolic extract from FE bark in an AlCl3-induced rat model of AD. MATERIALS AND METHODS: The maceration process was utilized to prepare the hydromethanolic extract of FE bark, and characterized by LC-MS/MS. To assess the anti-AD effects of the FE extract, rats were categorized into five different groups, AlCl3; normal control; FE-treated groups at 50, 100, and 200 mg/kg. Passive avoidance learning test, Y-maze, open field, and elevated plus maze behavioral tests were evaluated on days 7 and 14 to analyze the cognitive impairments. Zymography analysis, biochemical tests, and histopathological changes were also followed in different groups. RESULTS: LC-MS/MS analysis indicated the presence of coumarins, including isofraxidin7-O-diglucoside in the methanolic extract of FE as a new isofraxidin derivative in this genus. FE significantly improved memory and cognitive function, maintained weight, prevented neuronal damages, and preserved the hippocampus's histological features, as demonstrated by behavioral tests and histopathological analysis. FE increased anti-inflammatory MMP-2 activity, whereas it decreased that of inflammatory MMP-9. Moreover, FE increased plasma antioxidant capacity by enhancing CAT and GSH while decreasing nitrite levels in the serum of treated groups. In comparison between the treated groups, the rats that received high doses of the FE extract (200 mg/kg) showed the highest therapeutic effect. CONCLUSION: FE rich in coumarins could be an effective anti-AD adjunct agent, passing through antioxidant and anti-inflammatory pathways. These results encourage further studies for the development of this extract as a promising agent in preventing, managing, or treating AD and related diseases.

Effects of Phoenix dactylifera against Streptozotocin-Aluminium Chloride Induced Alzheimer's Rats and Their In Silico Study.

Phoenix dactylifera is known for medicinal importance due to its antioxidant, antidiabetic, antidepressant, and anti-inflammatory properties. This study is aimed at evaluating the effect of P. dactylifera seeds to cure Alzheimer's disease (AD). AD was induced in the rats with streptozotocin + aluminium chloride followed by treatment of methanolic extract of P. dactylifera seeds. The blood glucose levels were determined at regular intervals, which showed a prominent decrease in the extracts treated group. Behavior tests, including the Elevated Plus Maze (EPM) test and Morris Water Maze (MWM) test, were used to evaluate memory patterns in rats. The results indicated that extract-treated rats significantly improved memory behavior compared to the diseased group. After dissection, the serum electrolytes, antioxidant enzymes, and choline esterase enzymes were measured in different organs. The serum parameters creatinine, urea, and bilirubin increased after extract treatment. Similarly, the level of antioxidant enzymes like peroxidases (POD), glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), and thiobarbituric acid reactive substance (TBARS) in the extract-treated group showed improved results that were close to the normal control group. The enzyme (lipase, insulin, amylase, and acetylcholine) levels were found enhanced in extract groups as compared to diseased rats. High-performance liquid chromatography (HPLC) was used to determine the level of dopamine and serotonin neurotransmitters, which were increased significantly for P. dactylifera seeds with values of 0.18 µg/mg tissue and 0.56 µg/mg tissue, respectively. Overall, results showed that P. dactylifera seeds proved to be quite efficient in improving the memory and behavior of treated rats. The antioxidants and enzymes were also increased; therefore, it may be a potential candidate for treating AD.

Selenium Nanoparticles-Enriched Lactobacillus casei ATCC 393 Prevents Cognitive Dysfunction in Mice Through Modulating Microbiota-Gut-Brain Axis.

Purpose: The bidirectional communication between the gut and the central nervous system mediated by gut microbiota is closely related to the occurrence and development of neurodegenerative diseases, including Alzheimer's disease (AD). Selenium (Se) has been identified as playing a role against AD. Probiotics have beneficial effects on host brain function and behavior by modulating the microbiota-gut-brain axis. Herein, we evaluated the protective effects of Lactobacillus casei ATCC 393 (L. casei ATCC 393) and selenium nanoparticles-enriched L. casei ATCC 393 (L. casei ATCC 393-SeNPs) against D-galactose/aluminum chloride-induced AD model mice. Methods: The Morris Water Maze (MWM) test was used to assess cognitive function of mice. The morphology and histopathological changes, antioxidant capacity and immune responses in the brain and ileum were evaluated. The alterations in intestinal permeability of the mice were determined using FITC-dextran. Gut microbiota composition was assessed using 16s rRNA sequencing. Results: Thirteen weeks intervention with L. casei ATCC 393 or L. casei ATCC 393-SeNPs significantly improved cognitive dysfunction, and minimized amyloid beta (Aß) aggregation, hyperphosphorylation of TAU protein, and prevented neuronal death by modulating Akt/cAMP-response element binding protein (CREB)/brain-derived neurotrophic factor (BDNF) signaling pathway. Moreover, compared with L. casei ATCC 393, L. casei ATCC 393-SeNPs further effectively mitigated intestinal barrier dysfunction by improving antioxidant capacity, regulating immune response, restoring gut microbiota balance, and increasing the level of short-chain fatty acids and neurotransmitters, thereby inhibiting the activation of microglia and protecting brain neurons from neurotoxicity such as oxidative stress and neuroinflammation. Conclusion: These findings indicated that targeting the microbiota-gut-brain axis with L. casei ATCC 393-SeNPs may have therapeutic potential for the deficits of cognitive function in the AD model mice. Thus, we anticipate that L. casei ATCC 393-SeNPs may be a promising and safe Se nutritional supplement for use as a food additive to prevent the neurodegenerative disease.

Pharmacological evaluation of bromelain in mouse model of Alzheimer's disease.

The current study elucidates pharmacological evaluation of bromelain as a bioactive compound obtain from pineapple stem belongs to family Bromeliaceae in AlCl3 and D - galactose induced mice. In mice, co-administration of AlCl3 at dose 5 mg/kg b.w., via the oral route, and D - galactose at dose 60 mg/kg b.w., via intraperitoneal route for 90 days resulted in cognitive impairment, spatial learning, and memory deficits, as well as neurotoxicity. However, 30 consecutive days, treatments via an intraperitoneal route with bromelain low dose (Brm L) at dose 10 mg/kg b.w., bromelain high dose (Brm H) at dose 20 mg/kg b.w., donepezil (Dnpz) at dose 2 mg/kg b.w., and Brm L + Dnpz at doses 10, 2 mg/kg b.w. were considerably reversed the effect of AlCl3 and D - galactose induced AD mice. Consequences of behavioral parameters (Morris water maze, elevated plus maze and locomotor), biochemical estimation (MDA, GSH, SOD, CAT, Nitrite and AChE), and ELISA tests (mouse BACE, Aß1 - 42, TNF-α, IL-6, and BDNF) confirmed significant (p < 0.05) neuroprotective effect of treatments in AlCl3 and D - galactose induced mice. Additionally, hematoxylin and eosin staining of the cerebral cortex and the hippocampus exposed eosinophilic lesions and hyperchromatic nuclei in AD mice, but these neurodegenerative effects were eliminated by Brm L, Brm H, Dnpz, and Brm L + Dnpz treatments. Thus, bromelain alone and in combination with donepezil prevent AlCl3 and D - galactose induced spatial learning and memory deficits, as well as cognitive impairment, by increasing cholinergic activity and synaptic plasticity, as well as reducing oxidative damage, neuroinflammation, Aß 1-42 aggregations, and histopathological damage, according to our findings. The present study consequences indicate that bromelain alone and in combination with donepezil appears to have neuroprotective properties. Henceforward, this may be a promising treatment option for Alzheimer's disease.

Centella asiatica Alleviates AlCl3-induced Cognitive Impairment, Oxidative Stress, and Neurodegeneration by Modulating Cholinergic Activity and Oxidative Burden in Rat Brain.

Aluminum (Al) is linked to the development of many neurological disorders such as Alzheimer's disease (AD), Parkinson's disease, and autism. Centella asiatica (CA) is a regenerating herb traditionally used to stimulate memory. This study was designed to assess the neuroprotective role of ethanolic extract of CA (CAE) in AlCl3-induced neurological conditions in rats. Adult rats were chronically treated with AlCl3 (100 mg/kg b.w./day) for 60 days to establish the dementia model, and co-administration of CAE was evaluated for its ability to attenuate the toxic effect of AlCl3. CAE was given orally at a dose of 150 and 300 mg/kg b.w./day, for 60 days. The behavioral performances of rats were tested through Y-maze and open field tests. Lipid peroxidation, superoxide dismutase, and catalase activity were evaluated to measure oxidative stress; and acetylcholinesterase (AChE) activity was assessed to evaluate cholinergic dysfunction in the rat brain. H&E staining was used to assess structural abnormalities in the cortex and hippocampus. The result showed that AlCl3 induces cognitive dysfunction (impaired learning and memory, anxiety, diminished locomotor activity), oxidative stress, cholinergic impairment, and histopathological alteration in the rat brain. Co-administration of CAE with AlCl3 markedly protects the brain from AlCl3-induced cognitive dysfunction, oxidative stress, AChE activity, and cytoarchitectural alterations. Furthermore, 15 days CAE treatment after 45 days AlCl3 administration markedly ameliorates the AlCl3-induced neurotoxicity indicating its potential for therapeutic use.

Synergistic effect of photobiomodulation and phthalocyanine photosensitizer on fibroblast signaling responses in an in vitro three-dimensional microenvironment.

Photobiomodulation (PBM) is a promising medical treatment modality in the area of photodynamic therapy (PDT). In this study, we investigated the effect of combined therapy in a 3D microenvironment using aluminum chloride phthalocyanines (AlClPc) as the photosensitizing agent. Normal human fibroblast-containing collagen biomatrix was prepared and treated with an oil-in-water (o/a) AlClPc-loaded nanoemulsion (from 0.5 to 3.0 µM) and irradiated at a range of fluences (from 0.1 to 3.0 J/cm2) using a continuous-wave light-emitting diode (LED) irradiation system (660 nm). PBM at 1.2 J/cm2 and AlClPc/NE at 0.5 µM modified the fibroblast signaling response under 3D conditions, promoting collagen synthesis, ROS production, MMP-9 secretion, proliferation of the actin network, and facile myofibroblastic differentiation. PBM alone (at 1.2 J/cm2 and 0.3 J/cm2) had no significant effect on any of these parameters. The combined therapy affected myofibroblastic differentiation, inflammatory response, and extracellular matrix pliability, and should thus be examined further in subsequent studies considering that no side effects of PBM have been reported. Even though significant progress has been made in the field of phototherapy in recent years, it is necessary to further elucidate the detailed mechanisms underlying its effects already shown in 2D conditions to increase the acceptance of this beneficial and non-invasive therapeutic approach.

Biological Effects of Aqueous Extract of Laurus noboilis L. Leaves on Some Histological and Immunological Parameters in Male Rat Liver Affected by Aluminum Chloride.

The present current study aimed to assess the protective effect of the aqueous extract of Laurus noboilis L. leaves against the toxic effects of aluminum chloride on liver tissue. A number of 36 male albino rats (Wistar) were randomly assigned to six groups (n=6) and treated for 30 days: Group 1 was regarded as the control group, Group 2 received Aluminum Chloride 90 mg/kg body weight orally by gavage, Group3: normal rats received aqueous extracts of Lurus Nobilis L. leaf 150 mg/kg body weight, Group 4: normal rats received aqueous extracts of Lurus Nobilis L. leaf 200 mg/kg body weight, Group 5: normal rats received aqueous extracts of Lurus Nobilis L. leaf 150 mg/kg body weight after a period of 4 h following treatment by Aluminum Chloride 90 mg/kg body weight, Group 6: normal rats received aqueous extracts of Laurus nobilis L. 200 mg /kg after a period of 4 h following treatment by Aluminum chloride with 90 mg/kg body weight. All the experimental animals were sacrificed, and sections of their liver were stained with Hematoxylin-Eosin for histological evaluations. Moreover, the liver enzymes and immune cytokines, such as Alkaline phosphatase (ALP), Alanine aminotransferase (ALT), and Aspartate aminotransferase (AST), tumor necrosis factor-alpha (TNF-alpha), and interleukin-10 (IL-10) were measured. As evidenced by the results of the current study, treatment with aqueous extract of Lurus Nobilis L. leaves at a dose of 150 and 200 mg/kg body weight orally contributed to the mitigation of the toxic effects of Aluminum Chloride in albino rats by reducing the damage and inflammation in the hepatocytes. The study suggested that the aqueous extract of Lurus Nobilis L. enhances the protective effect against liver toxicity.

Aluminum and aluminum oxide nanomaterials uptake after oral exposure - a comparative study.

The knowledge about a potential in vivo uptake and subsequent toxicological effects of aluminum (Al), especially in the nanoparticulate form, is still limited. This paper focuses on a three day oral gavage study with three different Al species in Sprague Dawley rats. The Al amount was investigated in major organs in order to determine the oral bioavailability and distribution. Al-containing nanoparticles (NMs composed of Al0 and aluminum oxide (Al2O3)) were administered at three different concentrations and soluble aluminum chloride (AlCl3·6H2O) was used as a reference control at one concentration. A microwave assisted acid digestion approach followed by inductively coupled plasma mass spectrometry (ICP-MS) analysis was developed to analyse the Al burden of individual organs. Special attention was paid on how the sample matrix affected the calibration procedure. After 3 days exposure, AlCl3·6H2O treated animals showed high Al levels in liver and intestine, while upon treatment with Al0 NMs significant amounts of Al were detected only in the latter. In contrast, following Al2O3 NMs treatment, Al was detected in all investigated organs with particular high concentrations in the spleen. A rapid absorption and systemic distribution of all three Al forms tested were found after 3-day oral exposure. The identified differences between Al0 and Al2O3 NMs point out that both, particle shape and surface composition could be key factors for Al biodistribution and accumulation.

Nootropic effect of neferine on aluminium chloride-induced Alzheimer's disease in experimental models.

Alzheimer's disease (AD) is an age-associated neurodegenerative disease, which is developed by oxidative stress and acetylcholine contraction in the synaptic cleft of the neurons. This leads to dementia, memory loss, and decrease in learning ability and orientation. In this research work, we aimed to explore the neuroprotective effect of neferine on AlCl3 -induced AD in rats. The results of our study revealed that the increased reactive oxygen species (ROS) and nitric oxide in the hippocampus leads to the development of AD in the rats. The oral treatment of neferine done the following occurrences such as; it potentially inhibited the ROS formation and acts as a scavenging molecule by preventing the neurodegeneration. It also improved the memory and learning ability to complete the maze activity in the AD rats and significantly increased the antioxidants superoxide dismutase, catalase, and reduced glutathione in neferine treated AD rats. It aggressively declined the activity of acetylcholine esterase and Na+ K+ ATPase in the neurodegenerative rat models. The gene expression pattern of neuroinflammatory cytokines such as tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) were decreased in the neferine-treated rats. The neuroinflammatory proteins such as inducible nitric oxide (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor kappa ß (Nf-κß) were decreased and Nf-κß inhibitor IKBα was increased in the neferine-treated AD rats. Finally, the histology study proved that the neferine treatment possibly prevents neurodegeneration in the hippocampus tissue of the AD models. Hence, these all findings concluded that the neferine could be a potential neuropreventive as well as neurodegenerative therapeutic compound in neurological and cognitive dysfunction.

Protective Effect of Rosa damascena Against Aluminum Chloride-Induced Oxidative Stress.

Aluminum is considered an essential element endowed with toxicity potentials in human and animal. Thus, intoxication with aluminum can lead to oxidative stress, which is associated with oxidative damage to various macromolecules. Moreover, antioxidants from natural sources can play an important role in human health. Accordingly, the purpose of this study was to investigate the protective effect of Rosa damascena extract against aluminum-induced oxidative stress. In this study, 60 male rats were randomly divided into six groups and then they were given daily aluminum chloride and Rosa damascena extract. After 8 weeks of treatment, the levels of total antioxidant and malondialdehyde, as well as antioxidant enzymes including catalase, glutathione S-transferase, and myeloperoxidase, were measured in all experimental groups in this study. A significant increase was found in the total antioxidant level in the rats treated with aluminum, Rosa damascena extract, and aluminum plus Rosa damascena extract compared with those in the control group. Also, malondialdehyde levels were not significantly different in all the studied groups. Glutathione S-transferase activity levels in rats receiving the Rosa damascena extract as well as rats taking aluminum with Rosa damascena extract increased significantly compared with the ones in the control group. Catalase activity in the aluminum-treated group also increased significantly compared with the rates in the control group (31.34 ± 4.50 U/gHb vs. 14.04 ± 6.17 U/gHb, p = 0.014). Furthermore, myeloperoxidase activity in the aluminum-treated group increased significantly compared with the control group (49.47 ± 5.12 U/L vs. 25.28 ± 2.18 U/L, p < 0.001). The Rosa damascena extract could improve antioxidant capacity and reduce oxidative conditions in rats receiving aluminum chloride as evidenced by assays of the ferric reducing ability of plasma and activity of antioxidant enzymes. According to the findings of this study, it can be concluded that the Rosa damascena extract with its high antioxidant content is able to exert a protective effect against aluminum-induced oxidative stress.

Cognitive-Enhancing Effect of a Hydroethanolic Extract of Crinum macowanii against Memory Impairment Induced by Aluminum Chloride in BALB/c Mice.

Crinum macowanii is a bulbous plant indigenous to many parts of Southern Africa. Extracts of C. macowanii have gained interest since the discovery of various alkaloids, few of which possess acetylcholinesterase inhibitory activity. The present study was performed to evaluate the effect of a crude hydroethanolic extract of C. macowanii against aluminum chloride-induced memory impairment in mice using the Morris water maze and the novel object recognition task. C. macowanii (10, 20, and 40 mg/kg p.o) was administered daily for five weeks, while donepezil (3 mg/kg p.o) was used as the positive control. C. macowanii at a dosage of 40 mg/kg showed a significantly lower escape latency than the negative control (P < 0.0001) and was found to be comparable to donepezil 3 mg/kg in the Morris water maze test. C. macowanii at 40 mg/kg exhibited a significantly higher discrimination index than aluminum chloride-treated mice in the novel object recognition task. The results may support the usefulness of C. macowanii in the management of dementia and related illnesses.

Detrimental effects of chia (Salvia hispanica L.) seeds on learning and memory in aluminum chloride­induced experimental Alzheimer's disease.

Polyphenols and omega­3 fatty acids are thought to have beneficial effects in Alzheimer's disease, the most common cause of dementia. Seeds of chia (Salvia hispanica L.) are highly rich in these nutrients, and thus, the present study investigated the effects of chia seeds on behavior and cognition in an aluminum­induced Alzheimer's disease model in rats. Experimental animals received chia supplementation either during the generation of the model (i.e., pretreatment) or after the model was established (i.e., treatment). A battery of behavioral and cognitive tests were performed, including open­field, elevated plus maze, Porsolt's forced swim, and Morris' water maze, to evaluate anxiety­ and depression­like behaviors, and learning and memory. Results showed that chia supplementation was ineffective against Alzheimer's­related anxiety, whereas depression­like behaviors were attenuated with both pretreatment and treatment. There was no improvement in learning and memory with chia treatment. Rather, cognitive performance in chia­pretreated animals was remarkably worse as compared to their non­treated disease­induced counterparts. Hippocampal concentrations of amyloid-ß42, amyloid precursor protein, and total tau protein were similarly increased in all disease­induced animals (despite chia supplementation), as compared to the controls. Based on these findings, chia supplementation during the progression of Alzheimer's disease may exacerbate the disease. Although the results presented here emerge from an experimental/preclinical study, we suggest cautious and careful use of chia, especially in early­stage Alzheimer's patients, until future research in different experimental settings is conducted.