Hypericum perforatum extract attenuates behavioral, biochemical, and neurochemical abnormalities in Aluminum chloride-induced Alzheimer’s disease rats

Hypericum perforatum: a comprehensive review on pharmacognosy, preclinical studies, putative molecular mechanism, and clinical studies in neurodegenerative diseases

The herb Hypericum perforatum, also referred to as St. John's wort, has drawn a lot of interest because of its potential therapeutic benefits in treating neurodegenerative illnesses. Due to the absence of effective therapies, illnesses like Alzheimer's and Parkinson's disease pose an increasing worldwide health concern. Because of its wide variety of phytochemicals, especially hyperforin, and hypericin, Hypericum perforatum is well known for its neuroprotective properties. These substances have proven to be able to affect different cellular processes linked to neurodegeneration. They can act as anti-inflammatory, antioxidant, and neurotransmitter system regulators, which may help halt neurodegenerative illnesses' progression. The use of Hypericum perforatum extracts and its contents has shown encouraging results in research on animal models of neurodegenerative disorders. These advantages include higher nerve cell survival, lowered oxidative stress, and higher cognitive performance. Underscoring its versatile potential to combat neurodegeneration, Hypericum perforatum has neuroprotective mechanisms that modulate neuroinflammation and prevent apoptotic pathways. In conclusion, Hypericum perforatum shows tremendous promise as a potential treatment for neurological illnesses due to its wide variety of phytochemicals. To completely comprehend its specific mechanisms of action and turn these discoveries into efficient clinical therapies, additional research is needed. Investigating Hypericum perforatum's function in neurodegenerative disorders may present new opportunities for the advancement of ground-breaking therapeutic strategies.

Synthesis of Novel Hydrazide-Hydrazone Compounds and In Vitro and In Silico Investigation of Their Biological Activities against AChE, BChE, and hCA I and II

The abnormal levels of the human carbonic anhydrase isoenzymes I and II (hCA I and II) and cholinesterase enzymes, namely, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), are linked with various disorders including Alzheimer's disease. In this study, six new nicotinic hydrazide derivatives (7-12) were designed and synthesized for the first time, and their inhibitory profiles against hCA I, hCA II, AChE, and BChE were investigated by in vitro assays and in silico studies. The structures of novel molecules were elucidated by using spectroscopic techniques and elemental analysis. These molecules showed inhibitory activities against hCA I and II with IC50 values ranging from 7.12 to 45.12 nM. Compared to reference drug acetazolamide (AZA), compound 8 was the most active inhibitor against hCA I and II. On the other hand, it was determined that IC50 values of the tested molecules ranged between 21.45 and 61.37 nM for AChE and between 18.42 and 54.74 nM for BChE. Among them, compound 12 was the most potent inhibitor of AChE and BChE, with IC50 values of 21.45 and 18.42 nM, respectively. In order to better understand the mode of action of these new compounds, state-of-the-art molecular modeling techniques were also conducted.

Four New Polyprenylated Acylphloroglucinols from Hypericum perforatum L

Hyperforatums A-D (1-4), four new polyprenylated acylphloroglucinols, together with 13 known compounds were isolated and identified from the aerial parts of Hypericum perforatum L. (St. John's wort). Their structures were confirmed with a comprehensive analysis comprising spectroscopic methods, including 1D and 2D NMR, HRESIMS, and electronic circular dichroism (ECD) calculations. Hyperforatum A featured an unusual chromene-1,4-dione bicyclic system, and hyperforatums B and C were two rare monocyclic PPAPs with five-membered furanone cores. Compound 1 exhibited a moderate inhibition effect on NO production in BV-2 microglial cells stimulated by LPS.

Insight into the emerging and common experimental in-vivo models of Alzheimer's disease

Alzheimer's disease (AD) is a multifactorial, rapidly progressing neurodegenerative disorder. As the exact cause of the disease is still unclear, the drug development is very challenging. This review encompasses the commonly used AD models involving various chemicals, heavy metals and endogenous substances induced models and the transgenic models. It also provides insight into the reliable emerging models of AD that may overcome the shortcomings associated with available models. Chemicals like streptozotocin, scopolamine, colchicine and okadaic acid render the animal susceptible to neuroinflammation and oxidative stress induced neurodegeneration along with amyloid-β deposition and tau hyperphosphorylation. Similarly, endogenous substances like acrolein and amyloid-β 1-42 are efficient in inducing the major pathologies of AD. Heavy metals like aluminum and fluoride and mixture of these have been reported to induce neurotoxicity therefore are used as animal models for AD. Transgenic models developed as a result of knock-in or knock-out of certain genes associated with AD including PDAPP, APP23, Tg2576, APP/PS1, 3 × Tg and 5 × FAD have also been incorporated in this study. Further, emerging and advanced pathomimetic models of AD are provided particular interest here which will add on to the current knowledge of animal models and may aid in the drug development process and deepen our understanding related to AD pathogenesis. These newly discovered models include oAβ25-35 model, transgenic model expressing 82-kDa ChAT, oDGal mouse and APP knock-in rat. This study may aid in the selection of suitable model for development of novel potent therapeutics and for exploring detailed pathogenic mechanism of AD.

Neuroprotective and Cardiometabolic Role of Vitamin E: Alleviating Neuroinflammation and Metabolic Disturbance Induced by AlCl3 in Rat Models

Cardiovascular diseases (CVDs) and neurodegenerative disorders, such as diabetes mellitus and Alzheimer's disease, share a common pathophysiological link involving insulin resistance (IR), inflammation, and hypertension. Aluminium chloride (AlCl3), a known neurotoxicant, has been associated with neurodegeneration, cognitive impairment, and various organ dysfunctions due to the production of reactive oxygen species (ROS) and oxidative stress. In this study, we aimed to investigate the potential protective effects of metformin and vitamin E against AlCl3-induced neuroinflammation and cardiometabolic disturbances in rat models. Rats were divided into five groups: a normal control group, an AlCl3-treated diseased group without any treatment, and three groups exposed to AlCl3 and subsequently administered with metformin (100 mg/kg/day) alone, vitamin E (150 mg/kg/day) orally alone, or a combination of metformin (100 mg/kg/day) and vitamin E (150 mg/kg/day) for 45 days. We analyzed serum biomarkers and histopathological changes in brain, heart, and pancreatic tissues using H&E and Masson's trichrome staining and immunohistochemistry (IHC). Electrocardiogram (ECG) patterns were observed for all groups. The AlCl3-treated group showed elevated levels of inflammatory biomarkers, MDA, and disturbances in glycemic and lipid profiles, along with reduced insulin levels. However, treatment with the combination of metformin and vitamin E resulted in significantly reduced glucose, cholesterol, LDL, and TG levels, accompanied by increased insulin and HDL levels compared to the individual treatment groups. Histopathological analyses revealed that combination therapy preserved neuronal structures, muscle cell nuclei, and normal morphology in the brain, heart, and pancreatic tissues. IHC demonstrated reduced amyloid plaques and neurofibrillary tangles in the combination-treated group compared to the AlCl3-treated group. Moreover, the combination group showed a normal ECG pattern, contrasting the altered pattern observed in the AlCl3-treated group. Overall, our findings suggest that metformin and vitamin E, in combination, possess neuroprotective and cardiometabolic effects, alleviating AlCl3-induced neuroinflammation and metabolic disturbances.

Pachira macrocarpa Schltdl. & Cham., HPLC Profile, and Neuroprotective Potential via Regulation of JNK, miRNA132, and miRNA-125b

In this study, we investigated the polyphenolic profile of Pachira macrocarpa Schltdl. & Cham. by HPLC analysis and we also isolated three compounds from the ethyl acetate leaf extract, which were identified by different spectral data as vitexin 1, luteolin 2, and ferulic acid 3. Moreover, we investigated the three isolated compounds and the plant extract for their therapeutic potential against AlCl3 exposure-induced neurotoxicity in rats. This investigation aims to determine whether vitexin, luteolin, and ferulic acid in Pachira macrocarpa Schltdl. & Cham. extract (P. macrocarpa) have the ability to treat AlCl3-induced brain toxicity in rats. Six groups of rats were created: group 1 (normal group), group 2 treated with AlCl3, and groups 3, 4, 5, and 6 treated with AlCl3 with vitexin, luteolin, ferulic acid, and P. macrocarpa extract, respectively, for 28 days. Neurotoxicity was assessed by measuring plasma IL-8 and IL-33 as well as brain superoxide dismutase (SOD), glutathione reductase (GSR), B-cell lymphoma-2 (BcL-2), B-cell lymphoma-2 associated-x (Bax), and neurogranin using the ELISA technique and c-Jun N-terminal kinase (JNK), miRNA-125b, and miRNA-132 levels using western blot and PCR. HPLC analysis identified major phenolics and flavonoids. Among the phenolics identified, chlorogenic acid was prevalent (2159.14 μg/g), and regarding flavonoids, rutin was prevalent (204.69 μg/g). A significant elevation of IL-8 and IL-33 as well as brain Bax, neurogranin, and JNK levels and of miRNA-125b gene expression levels was observed following AlCl3 exposure. However, significant depletion of SOD, GSR, BcL-2, total protein, and miRNA-132 gene expression was observed in AlCl3-treated rats. Administration of the P. macrocarpa extract and its isolated compounds significantly increased SOD, GSR, BcL-2, total protein, and miRNA132 gene expression and decreased IL-8 and IL-33 as well as brain Bax, neurogranin, and JNK levels and brain miRNA-125b gene expression compared to AlCl3-treated rats. P. macrocarpa extract and its isolated compounds ameliorated AlCl3-induced oxidative stress and neurotoxicity in rats.

Therapeutic potential of stem cells and acitretin on inflammatory signaling pathway-associated genes regulated by miRNAs 146a and 155 in AD-like rats

Alzheimer's disease (AD) is one of the most common causes of dementia. Several drugs are used to improve the symptoms, but do not stop AD progression. There are more promising treatments that may have a significant role in AD diagnosis and treatment such as miRNAs and stem cells. The present study aims to develop a new approach for AD treatment by mesenchymal stem cells (MSCs) and/or acitretin with special reference to inflammatory signaling pathway as NF-kB and its regulator miRNAs in AD-like rat model. Fourty-five male albino rats were allotted for the present study. The experimental periods were divided into induction, withdrawal, and therapeutic phases. Expression levels of miR-146a, miR-155, necrotic, growth and inflammatory genes were assessed using RT-qPCR. Histopathological examination of brain tissues was performed in different rat groups. The normal physiological, molecular, and histopathological levels were restored after treatment with MSCs and/or acitretin. The present study demonstrates that the miR-146a and miR-155 might be used as promising biomarkers for AD. MSCs and/or acitretin proved their therapeutic potential in restoring the expression levels of targeted miRNAs and their related genes concerning NF-kB signaling pathway.

The neuroprotective effect of ginsenoside Rb1 on the cerebral cortex changes induced by aluminium chloride in a mouse model of Alzheimer's disease: A histological, immunohistochemical, and biochemical study

Alzheimer's disease (AD) is one of the most common types of dementia among neurodegenerative disorders characterized by attention deficits and memory loss. Panax ginseng is a traditional Chinese herbal remedy that has been employed for millennia to manage dementia linked with aging and memory impairment. Ginsenoside Rb1 is one of Panax ginseng's most abundant components. The present work evaluated the neuroprotective effects of ginsenoside Rb1 on the cerebral cortex of AlCl₃-induced AD in adult male albino mice. Forty male mice were alienated arbitrarily into; control group, ginsenoside Rb1 group (70 mg/kg/day), AlCl₃ group (50 mg/kg/day), and ginsenoside Rb1-AlCl₃ group that received ginsenoside Rb1 one hour before AlCl₃. Oxidative stress parameters, Amyloid β (Aβ) and phosphorylated tau protein, and acetylcholine esterase (AChE) activity were measured. Cerebral cortex sections were evaluated histologically by light microscopic examination and immunohistochemistry. AlCl₃-induced memory impairment, Aβ and phosphorylated tau protein accumulation, and AChE elevation. Moreover, histopathological alterations in the cerebral cortex were reported in the form of irregular shrunken neurons and the surrounding neuropil showed vacuolation. Some neurons appeared with darkly stained nuclei, others had faintly stained ones. The synaptophysin expression was significantly decreased, while the expression of cleaved caspase-3, glial fibrillary acidic protein (GFAP), and ionized calcium-binding adaptor molecule 1 (Iba-1) were significantly elevated. It's interesting to note that these changes were attenuated in mice pretreated with ginsenoside Rb1. Collected data indicated that ginsenoside Rb1 showed a potential neuroprotective effect against cerebral cortex changes caused by AlCl₃ via suppression of Amyloid β and phosphorylated tau protein formation, oxidative stress correction, anti-apoptotic effect, and by minimizing gliosis.

Hyperhubeins A-I, Bioactive Sesquiterpenes with Diverse Skeletons from Hypericum hubeiense

Nine new sesquiterpenes, hyperhubeins A-I (1-9), and 14 known analogues (10-23) were isolated from the aerial portions of Hypericum hubeiense. Their structures and absolute configurations were determined unambiguously via spectroscopic analysis, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Compounds 1-3 possess an unprecedented sesquiterpene carbon skeleton. Further, a plausible biosynthetic pathway from farnesyl diphosphate (FPP) is proposed. The isolated phytochemicals were evaluated for neuroprotective and anti-neuroinflammatory properties in vitro. Compounds 1, 2, 5-8, 14, and 21 displayed notable neuroprotective activity against hydrogen peroxide (H₂O₂)-induced lesions in PC-12 cells at 10 μM. Additionally, compounds 1, 2, 12, and 13 exhibited inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV-2 microglial cells, with their IC₅₀ values ranging from 4.92 to 6.81 μM. Possible interactions between these bioactive compounds and inducible nitric oxide synthase (iNOS) were predicted via molecular docking. Moreover, Western blotting indicated that compound 12 exerted anti-neuroinflammatory activity by suppressing LPS-stimulated expression of toll-like receptor-4 (TLR-4) and inhibiting consequent activation of nuclear factor-kappa-B (NF-κB) signaling.

The Role and Mechanism of Hyperoside against Depression-like Behavior in Mice via the NLRP1 Inflammasome

BACKGROUND AND OBJECTIVES

Hypericum perforatum (HP) is widely used for depressive therapy. Nevertheless, the antidepressant effect and potential mechanism of hyperoside (Hyp), the main active component of HP, have not been determined.

MATERIALS AND METHODS

We performed ultra-performance liquid chromatography-quadrupole-time-of-flight-tandem mass spectrometry (UPLC-Q-TOF-MS/MS) technology to analyze the components in HP. Using data mining and network pharmacology methods, combined with Cytoscape v3.7.1 and other software, the active components, drug-disease targets, and key pathways of HP in the treatment of depression were evaluated. Finally, the antidepressant effects of Hyp and the mechanism involved were verified in chronic-stress-induced mice.

RESULTS

We identified 12 compounds from HP. Hyp, isoquercetin, and quercetin are the main active components of HP. The Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), the Analysis Platform, DrugBank, and other databases were analyzed using data mining, and the results show that the active components of HP and depression are linked to targets such as TNF-, IL-2, TLR4, and so on. A potential signaling pathway that was most relevant to the antidepressant effects of Hyp is the C-type lectin receptor signaling pathway. Furthermore, the antidepressant effects of Hyp were examined, and it is verified for the first time that Hyp significantly alleviated depressive-like behaviors in chronic-stress-induced mice, which may be mediated by inhibiting the NLRP1 inflammasome through the CXCL1/CXCR2/BDNF signaling pathway.

CONCLUSION

Hyp is one of the main active components of HP, and Hyp has antidepressant effects through the NLRP1 inflammasome, which may be connected with the CXCL1/CXCR2/BDNF signaling pathway.

Comparative Biochemical Profiling of Aluminum Chloride and Sodium Azide Induced Neuroinflammation and Cardiometabolic Disturbance

Comorbidities in human beings signify the numerous risk factors that increase the incidences of neuro- and cardio-metabolic disorders. Experimental models depicting comorbidities are important to explore the molecular pathophysiology that can help suggest appropriate treatment strategies. Tissue-accumulating potential and pathological effects of aluminium chloride (AlCl₃)and sodium azide (NaN₃) are well recognized. Hence, in the current work, we have for the first time aimed to investigate the unexplored potential of graded dose effects of AlCl₃ and NaN₃ in inducing early inflammation and cardiometabolic toxicity via comparative biochemical analysis of AlCl₃ and/or NaN₃. Rats were allocated into seven groups (n = 6). Group 1 was normal control. Remaining groups were given graded doses of AlCl₃ and/or NaN₃, as LD-AlCl₃ (AlCl₃ 40 mg), MD-AlCl₃ (AlCl₃ 45 mg), and HD-AlCl₃ (AlCl₃ 50 mg) representing low dose, medium dose, and high dose of AlCl₃, respectively, and the remaining as LD-NaN₃ (NaN₃ 13 mg), MD-NaN₃ (NaN₃ 15 mg), and HD-NaN₃ (NaN₃ 17 mg) representing low dose, medium dose, and high dose of NaN₃, respectively. Serum levels of glucose, insulin, lipid profile, inflammatory mediators like IL-6 and oxidative stress marker, and malondialdehyde (MDA) were analyzed. Likewise, subacute toxicity parameters were analyzed. Immunohistochemistry (IHC) and histopathology (H&E/Masson's trichrome staining) of brain, heart, and pancreatic tissues were done. ECG pattern of all groups was observed. HD-AlCl₃ was associated with elevated levels of inflammatory biomarkers, MDA, and glycemic and lipid profiles, whereas it decreased the insulin levels. HD-NaN₃ also showed the similar effects of aggravated inflammatory biomarkers, impaired glycemic and lipid profiles, but depicted the maximum mortality rate as compared to HD-AlCl₃. IHC showed prominent amyloid plaques and neurofibrillary tangle formation with MD-AlCl₃ and HD-AlCl₃ as compared to NaN₃-treated groups. Likewise, in brain tissues, vacuolation of white matter, vascular congestion, and hemorrhage were seen in HD-AlCl₃ treated group, while HD-NaN₃ induced death in animals. AlCl₃ exposure resulted in an inverted QRS complex, while exposure to NaN₃ showed ST depression but with increased mortality. AlCl₃ has better controlled results as compared to NaN₃ for induction of comorbid experimental animal model depicting early neuroinflammation and cardiometabolic disruption. These determined efforts facilitate the researchers for the development of clinically effective treatment strategies using such experimental models.

Role of nutraceuticals on neurodegenerative diseases: neuroprotective and immunomodulant activity

Neurodegeneration is a degenerative process characterized by the progressive loss of the structure and function of neurons that involves several immune cells. It is the primary cause of dementia and other several syndromes, known as neurodegenerative diseases. These disorders are age-related and it is estimated that by 2040 there will be approximately 81.1 million people suffering from these diseases. In addition to the traditional pharmacological therapy, in recent years nutraceuticals, naturally based compounds with a broad spectrum of biological effects: anti-aging, antioxidants, hypoglycaemic, hypocholesterolemic, anticancer, anxiolytic, antidepressant, etc., assumed an important role in counteracting these pathologies. In particular, several compounds such as astaxanthin, baicalein, glycyrrhizin, St. John's wort, and Ginkgo biloba L. extracts show particular neuroprotective and immunomodulatory abilities, involving several immune cells and some neurotransmitters that play a critical role in neurodegeneration, making them particularly useful in improving the symptoms and progression of neurodegenerative diseases.

Pomegranate juice moderates anxiety- and depression-like behaviors in AlCl3-treated male mice

PURPOSE

Aluminum trichloride (AlCl₃) exposure was proven to encourage some behavioral deficits and eventually induces anxiety and depression in rodents animals. Therefore, this experiment aimed to scout about the effects of pomegranate juice on anxiety- and depression-like behaviors caused by AlCl₃ in male mice.

METHODS

Six groups of male mice were administrated orally for 35 days by PJ and AlCl3. The control group (G-I) received tap water, while the PJ groups (G-II and G-III) were treated with 20 % and 40 % PJ, respectively. The AlCl₃ group (G-IV) was treated with 400 mg/kg/day of AlCl_3, and the last two groups (G-V and G-VI) were treated with AlCl₃ and 20 % PJ or 40 % PJ, respectively. Then, the open-field (O-F), elevated plus maze (EPM), tail suspension (TS), forced swimming (FS), and light/dark box (L/DB) tests were applied for anxiety- and depression-like behavior studies. In addition, neurotransmitters and oxidative parameters in the brain were evaluated. The plasma cortisol was measured at the end of the experiment.

RESULTS

Behavioral analyses showed that PJ inhibited AlCl₃-induced depressive and anxiogenic effects in the O-F, EPM, TS, FS, L/DB tests. In addition, neurochemical results indicated that PJ at 20 % concentration minimized the AlCl₃ toxicity on dopamine (DOP), serotonin (SER), and acetylcholinesterase (AChE) levels in the for-brain of male mice. Moreover, PJ moderated the AlCl₃ effects by decreasing the level of thiobarbituric acid reactive substances (TBARS), and enhancing catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST) and glutathione (GSH) activities. The plasma cortisol increased in male mice treated with AlCl3 and in a group treated with a high dose of PJ.

CONCLUSION

Our results proposed that the anxiety- and depression-like behaviors induced by AlCl₃ exposure in male mice can be ameliorated by PJ treatment, probably through the inhibition of oxidative damage and minimizing the changes in neurotransmitters and hormonal activity.

The association between water source and depressive symptoms in China: A cross-sectional and longitudinal study

BACKGROUND

This study investigates the associations between residential water sources and symptoms of depression and the relationships between switching residential water sources and symptoms of depression in middle-aged and elderly people in China.

METHODS

The cross-sectional study included 12,713 participants and the longitudinal study included 8,286 participants. Symptoms of depression were evaluated using the Center for Epidemiologic Studies Depression Scale. Multiple logistic and Cox regression analyses were used to identify associations between water sources and symptoms of depression.

RESULTS

Participants without tap water were more likely to have depressive symptoms than participants with tap water (odds ratio (OR): 1.30; 95% confidence interval (CI): 1.19-1.42) (hazard ratio (HR): 1.18; 95% CI: 1.09-1.28). The lack of access to tap water in residence was positively related to the prevalence and incidence of symptoms of depression in almost all subgroups. Changing the water source from non-tap to tap water decreased the risk of depressive symptoms (HR: 0.69; 95% CI: 0.60 - 0.79).

LIMITATIONS

The results may not be generalizable to the whole population.

CONCLUSIONS

These results suggest that no tap water in residence is a risk factor for depressive symptoms. Therefore, providing tap water in residence may help prevent depression.

Pharmacological implications of ipriflavone against environmental metal-induced neurodegeneration and dementia in rats

Long-term exposure to environmental neurotoxic metals is implicated in the induction of dementia and cognitive decline. The present study aims to illustrate the therapeutic role of ipriflavone as a synthetic isoflavone against environmental metal-induced cognitive impairment in rats. Dementia was induced by a mixture of aluminum, cadmium, and fluoride for 90 days followed by ipriflavone for a further 30 days.  Metal-treated animals exhibited abnormal behaviors in the Morris water maze task. Neuropathological biomarkers including oxidative stress (TBARS, NO, SOD, GPX, GST, and GSH), inflammation (TNF- α, IL-6, and IL-1β), neurotransmission (AChE and MAO), and insulin resistance (insulin, insulin receptor, and insulin-degrading enzyme) were altered, which consequently elevated the level of amyloid-β42 and tau protein in the hippocampus tissues inducing neuronal injury. Ipriflavone significantly (P < 0.05) ameliorated the neurobehavioral abnormalities and the cognitive dysfunction biomarkers via antioxidant/anti-inflammatory mechanism. Moreover, ipriflavone downregulated the mRNA expression level of amyloid precursor protein and tau protein, preventing amyloid plaques and neurofibrillary tangle aggregation at P < 0.05. A molecular docking study revealed that ipriflavone has a potent binding affinity towards AChE more than donepezil and acts as a strong AChE inhibitor. Our data concluded that the therapeutic potential of ipriflavone against dementia could provide a new strategy in AD treatment.

Attenuative Effects of Fluoxetine and Triticum aestivum against Aluminum-Induced Alzheimer's Disease in Rats: The Possible Consequences on Hepatotoxicity and Nephrotoxicity

BACKGROUND

Alzheimer's disease (AD) is a chronic neurological illness that causes considerable cognitive impairment. Hepatic and renal dysfunction may worsen AD by disrupting β-amyloid homeostasis at the periphery and by causing metabolic dysfunction. Wheatgrass (Triticum aestivum) has been shown to have antioxidant and anti-inflammatory properties. This work aims to study the effect of aluminum on neuronal cells, its consequences on the liver and kidneys, and the possible role of fluoxetine and wheatgrass juice in attenuating these pathological conditions.

METHOD

Rats were divided into five groups. Control, AD (AlCl₃), Fluoxetine (Fluoxetine and AlCl₃), Wheatgrass (Wheatgrass and AlCl₃), and combination group (fluoxetine, wheatgrass, and AlCl₃). All groups were assigned daily to different treatments for five weeks.

CONCLUSIONS

AlCl₃ elevated liver and kidney enzymes, over-production of oxidative stress, and inflammatory markers. Besides, accumulation of tau protein and Aβ, the elevation of ACHE and GSK-3β, down-regulation of BDNF, and β-catenin expression in the brain. Histopathological examinations of the liver, kidney, and brain confirmed this toxicity, while treating AD groups with fluoxetine, wheatgrass, or a combination alleviates toxic insults.

CONCLUSION

Fluoxetine and wheatgrass combination demonstrated a more significant neuroprotective impact in treating AD than fluoxetine alone and has protective effects on liver and kidney tissues.

A comprehensive review on medicinal herbs and novel formulations for the prevention of Alzheimer's disease

Alzheimer's disease (AD) is one of the most prevalent neurodegenerative diseases reported in the aging population across the globe. About 46.8 million people are reported to have dementia, and AD is mainly responsible for dementia in aged people. Alzheimer's disease (AD) is thought to occur due to the accumulation of β-amyloid (Aβ) in the neocortex portion of the brain, nitric oxide mediated dysfunctioning of blood-brain barrier, reduced activity of serine racemase enzyme, cell cycle disturbances, damage of N-methyl-D-aspartate (NMDA) receptors and glutamatergic neurotransmission. Modern treatment methods target the pathways responsible for the disease. To date, solely symptomatic treatments exist for this disease, all making an attempt to counterbalance the neurotransmitter disturbance. Treatments able to prevent or at least effectively modifying the course of AD, referred to as 'disease-modifying' drugs, are still under extensive research. Effective treatments entail a better indulgence of the herbal bioactives by novel drug delivery systems. The herbal bioactive administered by novel drug delivery systems have proved beneficial in treating this disease. This review provides detailed information about the role of medicinal plants and their formulations in treating Alzheimer disease which will be highly beneficial for the researchers working in this area.

Effects and mechanisms of natural products on Alzheimer's disease

Alzheimer's disease (AD) is the most common form of dementia in elderly people with a high incidence rate and complicated pathogenesis, and causes progressive cognitive deficit and memory impairment. Some natural products and bioactive compounds from natural sources show great potential in the prevention and treatment of AD, such as apple, blueberries, grapes, chili pepper, Monsonia angustifolia, cruciferous vegetables, Herba epimedii, Angelica tenuissima, Embelia ribes, sea cucumber, Cucumaria frondosa, green tea, Puer tea, Amanita caesarea and Inonotus obliquus, via reducing amyloid beta (Aβ) deposition, decreasing Tau hyperphosphorylation, regulating cholinergic system, reducing oxidative stress, inhibiting apoptosis and ameliorating inflammation. This review mainly summarizes the effects of some natural products and their bioactive compounds on AD with the potential molecular mechanisms.

Therapeutic Potential of Natural Products in Treating Neurodegenerative Disorders and Their Future Prospects and Challenges

Natural products derived from plants, as well as their bioactive compounds, have been extensively studied in recent years for their therapeutic potential in a variety of neurodegenerative diseases (NDs), including Alzheimer's (AD), Huntington's (HD), and Parkinson's (PD) disease. These diseases are characterized by progressive dysfunction and loss of neuronal structure and function. There has been little progress in designing efficient treatments, despite impressive breakthroughs in our understanding of NDs. In the prevention and therapy of NDs, the use of natural products may provide great potential opportunities; however, many clinical issues have emerged regarding their use, primarily based on the lack of scientific support or proof of their effectiveness and patient safety. Since neurodegeneration is associated with a myriad of pathological processes, targeting multi-mechanisms of action and neuroprotection approaches that include preventing cell death and restoring the function of damaged neurons should be employed. In the treatment of NDs, including AD and PD, natural products have emerged as potential neuroprotective agents. This current review will highlight the therapeutic potential of numerous natural products and their bioactive compounds thatexert neuroprotective effects on the pathologies of NDs.

Improving Cognition with Nutraceuticals Targeting TGF-β1 Signaling

Rescue of cognitive function represents an unmet need in the treatment of neurodegenerative disorders such as Alzheimer’s disease (AD). Nutraceuticals deliver a concentrated form of a presumed bioactive(s) agent(s) that can improve cognitive function alone or in combination with current approved drugs for the treatment of cognitive disorders. Nutraceuticals include different natural compounds such as flavonoids and their subclasses (flavan-3-ols, catechins, anthocyanins, and flavonols), omega-3, and carnosine that can improve synaptic plasticity and rescue cognitive deficits through multiple molecular mechanisms. A deficit of transforming growth factor-β1 (TGF-β1) pathway is an early event in the pathophysiology of cognitive impairment in different neuropsychiatric disorders, from depression to AD. In the present review, we provide evidence that different nutraceuticals, such as Hypericum perforatum (hypericin and hyperforin), flavonoids such as hesperidin, omega-3, and carnosine, can target TGF-β1 signaling and increase TGF-β1 production in the central nervous system as well as cognitive function. The bioavailability of these nutraceuticals, in particular carnosine, can be significantly improved with novel formulations (nanoparticulate systems, nanoliposomes) that increase the efficacy and stability of this peptide. Overall, these studies suggest that the synergism between nutraceuticals targeting the TGF-β1 pathway and current approved drugs might represent a novel pharmacological approach for reverting cognitive deficits in AD patients.

Neuroprotective effects of ononin against the aluminium chloride-induced Alzheimer's disease in rats

Alzheimer’s disease (AD) is a chronic neurodegenerative disease categorized by the deficiency in the cognition and memory. Approximately 50 million peoples has the AD, which is categorized by the deficiency in the cognition, memory and other kinds of cognitive dissention. The present exploration was designed to unveil the ameliorative properties of ononin against the aluminium chloride (AlCl3)-provoked AD in animals via the suppression of oxidative stress and neuroinflammation. AD was provoked to the Sprague Dawley rats through administering orally with 0.5 ml/100 g b.wt. of AlCl3 25 days and then supplemented with the 30 mg/kg of ononin orally for 25th day to 36th day. The behavioural changes were examined using open field and Morris Water Maze test. The acetylcholine esterase (AChE) activity was studied by standard method. The status of Aβ1-42, MDA, SOD, total antioxidant capacity (TAC) were quantified using respective assay kits. The interleukin(IL)-1β and TNF-α, BDNF, PPAR-γ, p38MAPK, and NF-κB/p65 status was quantified using respective assay kits. Brain histology was studied using microscope. The ononin treatment effectively modulated the AlCl3-triggered behavioural alterations in the AD animals. Ononin appreciably suppressed the AChE, Aβ1-42, and MDA and improved the SOD and TAC in the brain tissues of AD animals. The status of IL-1β, TNF-α, p38MAPK, and NF-κB were suppressed and the BDNF and PPAR-γ contents were elevated in the brain tissues of AD animals. The outcomes brain histology analysis proved the attenuate role of ononin. Our findings recommended that the ononin treatment could ameliorate the cognitive impairment, suppress the neuroinflammation and oxidative stress in the AD animals.

Identification of phytochemicals from North African plants for treating Alzheimer's diseases and of their molecular targets by in silico network pharmacology approach

BACKGROUND

The global social expenses of Alzheimer's disease (AD) have been increased to US$1 trillion due to high cost, side-effects, and low efficiency of the current AD-therapies. Another reason is the lack of preventive drugs and the low-income situation of Asian and African countries. Accordingly, patients rather prefer traditional herbal remedies. Network-pharmacology has been a well-established method for the visualization and the construction of disorder target protein-drug framework. This could aid in the identification of drugs molecular-mechanisms.

AIM

The aim of this study is to investigate the phytochemical constituents that could target Alzheimer's disease from the North African plants. This could be done by exploring their possible mechanisms of action through molecular network pharmacology-based approach.

EXPERIMENTAL PROCEDURE

The Phytochemical-compounds of North-African plants (NAP) have been accessed from open-databank. ADME-screening has been conducted for filtering of the NAP phytochemical-constituents utilizing Qikprop-software. The open STITCH databank has been utilized for the prediction of the phytochemical-constituents target-proteins; UniProt and TDD-DB databanks have been utilized for distinguishing AD-related proteins. Phytochemical constituent-target protein (C-T) and plant-phytochemical constituent-target protein (P-C-T) frameworks have been assembled utilizing Cytoscape to interpret the anti-Alzheimer's disease mechanism of action of the targeted phytochemical constituents.

RESULTS

The NAP 6842 phytochemical-constituents (from more than 1000 plants) have been exposed to ADME and CNS modulating filtration, generating 94 phytochemical-constituents which have been subjected to target-prediction investigation. The 94 phytochemical-constituents and the 4 AD-identified targets have been associated through 155 edges which formed the main pathways related to AD. Cuparene, alpha-selinene, beta-sesquiphellandrene, calamenene, 2-4-dimethylheptane, undecane, n-tetradecane, hexadecane, nonadecane, n-eicosane, and heneicosane have had C-T network highest combined-score, whilst the proteins MAO-B, HMG-CoA, BACE1, and GCR have been the most enriched ones by comprising the uppermost combined-scores of C-T. Hypericum perforatum, Piper nigrum, Juniperus communis, Levisticum officinale, Origanum vulgare acquired the uppermost number of P-C-Target interactions.

CONCLUSION

The phytochemical-targets prediction of NAP utilizing molecular-network pharmacology-based investigation has paved the way for networking multi-target, multi-constituent, and multi-pathway mechanisms. This may introduce potential future targets for the regulation and the management of Alzheimer's disease.

TAXONOMY CLASSIFICATION BY EVISE

Alzheimer's disease, Network pharmacology, In-silico computer based approach.

Potential of Caffeine in Alzheimer's Disease-A Review of Experimental Studies

Alzheimer's disease (AD) is the most common type of dementia leading to progressive memory loss and cognitive impairment. Considering that pharmacological treatment options for AD are few and not satisfactory, increasing attention is being paid to dietary components that may affect the development of the disease. Such a dietary component may be caffeine contained in coffee, tea or energy drinks. Although epidemiological data suggest that caffeine intake may counteract the development of cognitive impairment, results of those studies are not conclusive. The aim of the present study is to review the existing experimental studies on the efficacy of caffeine against AD and AD-related cognitive impairment, focusing on the proposed protective mechanisms of action. In conclusion, the reports of studies on experimental AD models generally supported the notion that caffeine may exert some beneficial effects in AD. However, further studies are necessary to elucidate the role of caffeine in the effects of its sources on cognition and possibly AD risk.

UPLC-Orbitrap HRMS metabolic profiling of Cymbopogon citratus cultivated in Egypt; neuroprotective effect against AlCl3-induced neurotoxicity in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Cymbopogon citratus (lemongrass) is commonly used in teas, soups and treat inflammatory-based ailments, vascular and nervous disorders.

AIM OF THE STUDY

The study aimed to evaluate the neuroprotective effect of Cymbopogon citratus leaves through scientific protocol. The effect of aqueous (AE) and ethanolic (EE) extracts was evaluated against AlCl₃-induced Alzheimer's disease (AD) in rats. Metabolic profiling of the plant, isolation of bioactive compounds and standardization of the active fraction were investigated.

MATERIALS AND METHODS

AE of Cymbopogon citratus leaves was prepared as per traditional method (infusion), EE was prepared by repeated maceration in 90% ethanol, bioactive fraction (BAEE) was obtained from EE and the active compounds thereof were obtained by column chromatography. Metabolic profiling of Cymbopogon citratus was performed by UPLC-Orbitrap HRMS and HPLC was used for standardization. AlCl₃-induced Alzheimer's rats were used to assess neuroprotective effect of the extracts. Neuroprotective mechanism(s) of Cymbopogon citratus extracts was clarified through histopathological examination of brain tissues, estimation of AD biochemical markers, oxidative stress and neuroinflammation in brain homogenates. In addition, antioxidant (using DPPH assay) and anticholinesterase (using modified Ellman's method) activities were investigated.

RESULTS

AlCl₃-treated rats (17 mg/kg/day) showed histopathological alteration in brain tissues together with elevated levels of Aβ, tau proteins, MDA, NF-kB and IL-6. However, treatment with AE and EE of Cymbopogon citratus leaves prevented the pathological changes and maintained the levels of oxidative stress and inflammatory markers. In addition, BAEE significantly inhibited acetylcholinesterase enzyme (2.11 ± 0.11 mg/ml) and exhibited a strong antioxidant activity (24.99 ± 0.00 μg/ml). UPLC-MS of Cymbopogon citratus leaves showed peaks for twenty-eight compounds, twenty-one of them were identified. Three flavonoids; isoorientin, isoschaftoside and luteolin-7-O-neohesperidoside were isolated from BAEE as major constituents. The powdered leaves of Cymbopogon citratus was found to contain remarkable amounts of caffeic acid (3.49 mg/g dry wt.) and isoorientin (7.37 mg/g dry wt.) as determined by HPLC.

CONCLUSION

Cymbopogon citratus ethanolic extract attenuates AlCl₃-induced neurotoxicity in rats through inhibition of oxidative stress and inflammatory markers. This effect could possibly attributed, in part to its high content of phenolic acids and flavonoids. Accordingly, we recommend Cymbopogon citratus leaves for protection against AD.

The Possible Neuroprotective Effect of Silymarin against Aluminum Chloride-Prompted Alzheimer's-Like Disease in Rats

Alzheimer's disease (AD) is a worldwide rapidly growing neurodegenerative disease. Here, we elucidated the neuroprotective effects of silymarin (SM) on the hippocampal tissues of aluminum chloride (AlCl3)-induced Alzheimer-like disease in rats using biochemical, histological, and ultrastructural approaches. Forty rats were divided into control, SM, AlCl3, and AlCl3 + SM groups. Biochemically, AlCl3 administration resulted in marked elevation in levels of lipid peroxidation (LPO) and nitric oxide (NO) and decrease in levels of reduced glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). Moreover, AlCl3 significantly increased tumor necrosis factor-α (TNF-α), interleukin-1beta (IL-1β), and acetylcholinesterase (AChE) activities. Furthermore, myriad histological and ultrastructural alterations were recorded in the hippocampal tissues of AlCl3-treated rats represented as marked degenerative changes of pyramidal neurons, astrocytes, and oligodendrocytes. Additionally, some myelinated nerve fibers exhibited irregular arrangement of their myelin coats, while the others revealed focal degranulation of their myelin sheaths. Severe defects in the blood-brain barrier (BBB) were also recorded. However, co-administration of SM with AlCl3 reversed most of the biochemical, histological, and ultrastructural changes triggered by AlCl3 in rats. The results of the current study indicate that SM can potentially mend most of the previously evoked neuronal damage in the hippocampal tissues of AlCl3-kindled rats.

St. John's Wort Herbal Teas - Biological Potential and Chemometric Approach to Quality Control

St. John's wort has been used for centuries in traditional medicine of many cultures, and nowadays it is well-known as a clinically important antidepressant drug. Considering the rising market demand for Hyperici herba, quality control of crude drug is of paramount importance. In this paper we performed HPLC-DAD chemical profiling of St. John's wort tea samples obtained at local markets, pharmacies and health food stores in the Balkan Peninsula countries, Austria and Turkey. Furthermore, water alcoholic extracts of the collected samples were evaluated in terms of their antioxidant potential, as well as the ability to inhibit biologically important enzymes such as acetylcholinesterase, monoamine oxidases A and B (MAO-A and MAO-B), α-amylase and α-glucosidase. Significant variability within the samples in the quantities of hypericin, hyperforin, rutin, quercetin, gallic, chlorogenic, caffeic and p-hydroxybenzoic acid was noticed. Chemotaxonomic modelling enabled the identification of three clusters of samples based on the quantities of rutin, hypericin and hyperforin. Generally, the extracts exhibited a significant potential to inhibit MAO-A (median IC₅₀ = 10.01 μg/mL) and α-glucosidase (median IC₅₀ = 12.40 μg/mL). The results of antioxidant potential evaluation suggest strong neutralization of hydroxyl and nitroso radicals, but moderate inhibition of lipid peroxidation process. Overall, the conducted study emphasizes the possibility of St. John's wort teas quality control, taking into account unavoidable variability of chemical profile as well. The stated is of great importance when grinding degree of herbal material excludes taxonomic identification of biological origin as an option within quality control.

Aluminum trichloride caused hippocampal neural cells death and subsequent depression-like behavior in rats via the activation of IL-1β/JNK signaling pathway

Aluminum (Al) is an inorganic pollutant that induces nerve cells apoptosis and necroptosis, thereby causing depression and neurodegenerative diseases. IL-1β/JNK signaling pathway can regulate apoptosis and necroptosis. However, it remains unclear whether IL-1β/JNK signaling pathway is involving in the regulation of Al-induced hippocampal neural cells apoptosis and necroptosis. To investigate the mechanism of Al on neural cells apoptosis and necroptosis, rats were orally exposed to different doses of AlCl₃ for 90 days. The open-field test results showed that AlCl₃ caused depressive behavior in rats. Histopathological evidence showed that AlCl₃ induced hippocampal neural cells apoptosis and necrosis. Moreover, Bax/Bcl-2 mRNA expression ratio, caspase-3 activity and mRNA expression and TUNEL positive rates were upregulated, meanwhile, TNF-α mRNA and protein expression levels, TNFR1, RIP1, RIP3 and MLKL proteins levels were increased, while caspase-8 protein level was decreased in the hippocampus of Al-exposed groups. These results proved that AlCl₃ induced hippocampal neural cells apoptosis and necroptosis. Combined with histopathology and correlation analysis, we deduced that hippocampal neural cells were more likely to undergo necroptosis at high doses (450 mg/kg) of AlCl₃, while <150 mg/kg AlCl₃ tended to induce apoptosis. Finally, AlCl₃ increased the proteins level of IL-1β, IL-1RI, IL-1RAcP, JNK and p-JNK, indicating that AlCl₃ activated IL-1β/JNK signaling pathway. However, the application of IL-1 receptor antagonist (IL-1Ra) inhibited the phosphorylation of JNK and the related genes expression of apoptosis and necroptosis caused by AlCl₃. Thus, we concluded that AlCl₃ induced hippocampal neural cells death and depression-like behavior in rats by activating IL-1β/JNK signaling pathway.

Deltamethrin induces liver fibrosis in quails via activation of the TGF-β1/Smad signaling pathway

Deltamethrin (DLM) is an important member of the pyrethroid pesticide family, and its widespread use has led to serious environmental and health problems. Exposure to DLM causes pathological changes in the liver of animals and humans and can lead to liver fibrosis. However, the mechanism of DLM-induced liver fibrosis remains unclear. Therefore, to address its potential molecular mechanisms, we used both in vivo and in vitro methods. Quails were treated in vivo by intragastric administration of different concentrations of DLM (0, 15, 30, or 45 mg kg^-1), and the chicken liver cancer cell line LMH was treated in vitro with various doses of DLM (0, 50, 200, or 800 μg mL^-1). We found that DLM treatment in vivo induced liver fibrosis in a dose-dependent manner through the promotion of oxidative stress, activation of transforming growth factor-β1 (TGF-β1) and phosphorylation of Smad2/3. Treatment of LMH cells with different concentrations of DLM similarly induced oxidative stress and also decreased cell viability. Collectively, our study demonstrates that DLM-induced liver fibrosis in quails occurs via activation of the TGF-β1/Smad signaling pathway.

Hypericum spp.: An Update on the Biological Activities and Metabolic Profiles

Plants from the genus Hypericum, one genus of the Hypericaceae family, have attracted a lot of attention for their potential pharmaceutical applications. Most of the studies in the literature focus on H. perforatum L. (common St. John's wort), whose complex spectrum of bioactive compounds makes this species one of the top herbal remedies and supplements in the world. It is also important to compare the studies on other Hypericum species, both from the phytochemical and biological point of view. The aim of this review was to provide an update of most recent studies about biological investigations of plants belonging to Hypericum genus. The metabolic profiles of Hypericum spp. were also discussed in order to present a spectrum of secondary metabolites not previously identified in this genus.

Vinpocetine mitigates aluminum-induced cognitive impairment in socially isolated rats

Several reports have highlighted the role of vinpocetine in Alzheimer's disease (AD). However, the role of vinpocetine in AD under social isolation conditions has not yet been elucidated. Henceforth, this study aimed to investigate the potential neuroprotective effect of vinpocetine in aluminum-induced AD model associated with social isolation. Social isolation increased the escape latency in Morris water maze (MWM) test, elevated the immobility score and decreased swimming score in forced swimming test (FST) in aluminum treated rats. However, vinpocetine enhanced acquisition in MWM test and exerted anti-depressive effect in FST. The histopathological examination showed marked deterioration in the cerebral cortex and hippocampus of AD isolated rats, while vinpocetine revealed overt improvement. In addition, the levels of amyloid-β protein (Aβ), phosphorylated-tau (Ser396), malondialdehyde (MDA), interleukin 1-beta (IL-1β), tumor necrosis alpha (TNFα), p- Glycogen synthase kinase-3β (p-GSK3β) (Tyr216), and β-secretase (BACE1) gene expression were increased in socially isolated aluminum treated rats, yet, vinpocetine treatment reversed these deteriorating effects. Hence, this study provides profound insights into the role of vinpocetine in AD particularly in the conditions of social isolation. The effects of vinpocetine might be attributed not only to its antioxidant and anti-inflammatory properties, but also to its suppressing effect on GSK3β activity and its downstream BACE1.

Dendritic spine loss caused by AlCl3 is associated with inhibition of the Rac 1/cofilin signaling pathway

Aluminum (Al) has neurotoxicity that can result in cognitive dysfunction. Hippocampal dendritic spine loss is a pathological characteristic of cognitive dysfunction. Our previous study reported that Al exposure caused dendritic spine loss in the hippocampus, but the underlying mechanism remains unclear. In this study, rats were orally administered 50, 150 or 450 mg/kg of AlCl₃ for 90 days. The dendritic spine density of the CA1 and DG regions was detected by Golgi-Cox staining. The F-actin/G-actin ratio, the expression of drebrin A and the components of the Rac 1/cofilin pathway were measured in the hippocampus. The results obtained showed that AlCl₃ caused dendritic spine loss and decreased the F-actin/G-actin ratio. In addition, it was found that AlCl₃ downregulated the expression of Rac 1, p-PAK, p-LIMK, p-cofilin and drebrin A and upregulated cofilin expression. Altogether, these results demonstrated that Al inactivated the Rac 1/cofilin pathway by inhibiting the phosphorylation of cofilin and the polymerization of F-actin, resulting in dendritic spine loss in the hippocampus.

Neuroprotective role of hyperforin on aluminum maltolate-induced oxidative damage and apoptosis in PC12 cells and SH-SY5Y cells

Many reports demonstrated that aluminum maltolate (Almal) has potential toxicity to human and animal. Our study has demonstrated that Almal can induce oxidative damage and apoptosis in PC12 cells and SH-SY5Y Cells, two in vitro models of neuronal cells. Hyperforin (HF) is a well-known antioxidant, anti-inflammatory, anti-amyloid and anti-depressant compound extracted from Hypericum perforatum extract. Here, we investigated the neuroprotective effect of HF against Almal-induced neurotoxicity in cultured PC12 cells and SH-SY5Y cells, mainly caused by oxidative stress. In the present study, HF significantly inhibited the formation of reactive oxygen species (ROS), decreased the level of lipid peroxide and enhanced the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) compared with Almal group in PC12 cells and SH-SY5Y cells. Additionally, HF suppressed the reduction of the mitochondrial membrane potential (MMP), cytochrome c (Cyt-c) release, activation of caspase-3, and the down-regulation of Bcl-2 expression and up-regulation of Bax expression induced by Almal in PC12 cells and SH-SY5Y cells. In summary, HF protects PC12 cells and SH-SY5Y cells from damage induced by Almal through reducing oxidative stress and preventing of mitochondrial-mediated apoptosis.

Hypericum perforatum in the treatment of psychiatric and neurodegenerative disorders: Current evidence and potential mechanisms of action

BACKGROUND

Psychiatric disorders are substantially associated with reduced quality of life and increased mortality. Depression and anxiety are two of the most common psychiatric disorders that often co-occur with each other as well as with other mental health conditions. Because of the limitations of currently available antidepressant therapies, there is a need for agents with improved efficacy and less adverse effects. Hypericum perforatum, widely known as St. John's wort, is a perennial herbaceous plant most well known for its antidepressant properties.

METHODS

We reviewed the available in vitro, in vivo, and clinical evidence on the efficacy, safety, and mechanisms of action of St. John's wort and its active constituents in the treatment of psychiatric and neurodegenerative disorders.

RESULTS

Several interesting data have been reported about the antidepressant properties of H. perforatum in clinical trials with different designs. In particular, a number of antidepressant-controlled trials demonstrated that H. perforatum and its active ingredients, hypericin and hyperforin, possess antidepressant properties similar to those of tricyclic antidepressants and selective serotonin reuptake inhibitors but with fewer and milder side effects.

CONCLUSION

St. John's wort may exert potent antidepressant effects and represents an efficacious and safe treatment. However, the current clinical evidence regarding the efficacy of H. perforatum in other psychiatric and neurodegenerative disorders is not sufficient to draw a robust conclusion.

Aluminum trichloride-induced hippocampal inflammatory lesions are associated with IL-1β-activated IL-1 signaling pathway in developing rats

Aluminum (Al) is a recognized environmental pollutant that causes neuroinflammatory lesions, leading to neurodegenerative diseases. Interleukin-1 (IL-1) signaling pathway is responsible for regulating inflammatory lesions. However, it remains unclear whether IL-1 signaling pathway is involved in neuroinflammatory lesions induced by Al exposure. In the present study, one hundred and twenty Wistar rats were orally exposed to 0, 50, 150 and 450 mg/kg BW/d aluminum trichloride (AlCl₃) for 90 days, respectively. We found that AlCl₃ exposure increased hippocampal Al concentration, reduced hippocampus coefficient, impaired cognitive ability, deteriorated microstructure of hippocampal CA1 and CA3 regions, increased reactive oxygen species (ROS) level, activated astrocytes and microglia, increased pro-inflammatory cytokines contents and mRNA expressions, and decreased anti-inflammatory cytokines contents and mRNA expressions in the hippocampus. These results indicated that AlCl₃ induced the hippocampal inflammatory lesion (HIL). Moreover, AlCl₃ exposure increased the mRNA and protein expression of IL-1 signaling pathway core components in the hippocampus, demonstrating that AlCl₃ activated IL-1 signaling pathway. Furthermore, the correlation between interleukin-1β (IL-1β) content and HIL and activation of the IL-1 signaling pathway was analyzed. Results showed that IL-1β content was positively correlated with pro-inflammatory cytokines contents and mRNA expressions and activation of IL-1 signaling pathway, and was negatively correlated with hippocampus coefficient, anti-inflammatory cytokines contents and mRNA expressions, and the number of hippocampal neurons. The above results demonstrate that AlCl₃-induced HIL is associated with IL-1 signaling pathway, in which IL-1β is a link.

Multiple pharmacological activities of Caesalpinia crista against aluminium-induced neurodegeneration in rats: Relevance for Alzheimer's disease

Alzheimer's disease (AD) is the most common form of dementia and mainly affects cognitive function of the aged populations. Aluminium, a neurotoxic metal, has been suggested as a contributing factor of AD. Caesalpinia crista is a medicinal plant known for its anti-microbial, anti-inflammatory and anti-oxidant properties. The present study was conducted in order to evaluate the neuroprotective effects of methanolic extracts of C. crista (MECC) on aluminium-induced neurodegeneration in rats. Co-administration with MECC significantly and dose dependently ameliorated the aluminium-dependent cognitive impairment, AChE hyperactivity and oxidative stress in the hippocampus and in the frontal cortex of rat brain. Moreover, MECC reduced the neuronal injury induced by aluminium as shown by the diminution of neuron loss and pyknosis in the CA1 and CA3 regions of the hippocampus. From this study, it is inferred that MECC protect against aluminium-induced behavioral alterations, cognitive function, oxidative stress and neuroinflammation in vivo. Therefore, this plant may serve as a source of natural products having multiple functions and could be utilized as an anti-AD preparation.

Neuroprotective effect of berberine against environmental heavy metals-induced neurotoxicity and Alzheimer's-like disease in rats

Heavy metals are reported as neurodegenerative disorders progenitor. They play a role in the precipitation of abnormal β-amyloid protein and hyper-phosphorylated tau, the main hallmarks of Alzheimer's disease (AD). The present study aimed to validate the heavy metals-induced Alzheimer's-like disease in rats as an experimental model of AD and explore the therapeutic effect of berberine via tracking its effect on the oxidative stress-inflammatory pathway. Alzheimer's-like disease was induced in rats orally by a mixture of aluminium, cadmium and fluoride for three months, followed by berberine treatment for another one month. Berberine significantly improved the cognitive behaviors in Morris water maze test and offered a protective effect against heavy metals-induced memory impairment. Docking results showed that berberine inhibited AChE, COX-2 and TACE. Matching with in silico study, berberine downregulated the AChE expression and inhibited its activity in the brain tissues. Also, it normalized the production of TNF- α, IL-12, IL-6 and IL-1β. Moreover, it evoked the production of antioxidant Aβ40 and inhibited the formation of Aβ42, responsible for the aggregations of amyloid-β plaques. Histopathological examination confirmed the neuroprotective effect of berberine. The present data advocate the possible beneficial effect of berberine as therapeutic modality for Alzheimer's disease via its antiinflammatory/antioxidant mechanism.