Berberine alters the processing of Alzheimer's amyloid precursor protein to decrease Abeta secretion

Unraveling Berberine's Molecular Mechanisms in Neuroprotection Against Neurodegeneration

Neurodegenerative diseases (NDs) exhibit significant global public health challenges due to the lack of effective treatments. Berberine (BBR), a natural alkaloid compound in various plants, has been recognized for its potential neuroprotective properties. This review explores the current understanding of BBR's mechanisms of action and its therapeutic potential in preventing and treating NDs such as Alzheimer's disease, Parkinson's disease, and Huntington's disease. BBR's neuroprotective properties are attributed to its multifaceted actions, including anti-inflammatory, antioxidant, antiapoptotic, and neurotrophic effects. In addition, BBR can influence many signaling pathways involved in neurodegeneration, including AMP-activated protein kinase (AMPK), nuclear factor erythroid 2-related factor 2, and brain-derived neurotrophic factor pathways. Furthermore, BBR targets vital signaling pathways, including AMPK, PI3K/Akt, and MAPK, which are essential for developing NDs. In addition, BBR's efficacy in reducing neurodegenerative pathology and improving cognitive function has been demonstrated through preclinical studies using cellular and animal models. Clinical trials demonstrating BBR's therapeutic potential in NDs have yielded promising results, but further research is needed to confirm its safety and efficacy in humans.

Neuroprotective Effects of Berberine Chloride Against the Aluminium Chloride-Induced Alzheimer's Disease in Zebra Fish Larvae

Alzheimer's disease (AD) is a neurodegenerative disease distinguished by cognitive and memory deficits. A lack of memory, cognition, and other forms of cognitive dissonance characterizes AD, which affects approximately 50 million people worldwide. This study aimed to identify the neuroprotective effects of berberine chloride (BC) against aluminium chloride (AlCl3)-induced AD in zebrafish larvae by inhibiting oxidative stress and neuroinflammation. BC toxicity was assessed by evaluating survival rates, malformations, and heart rates in zebrafish larvae following treatment with varying concentrations of BC. This study elucidates the mechanisms of BC through an extensive range of biochemical assays, behavioral testing, and molecular docking analysis. The developmental toxicity assessment of BC indicated that doses up to 40 μM did not cause any developmental abnormalities until 96 h post fertilization. The LC50 value of BC in zebrafish larvae was found to be 50.16 μM. The biochemical and behavioral changes induced by AlCl3 in zebrafish larvae were significantly mitigated by BC treatment. Our findings demonstrate that BC can reduce total cholesterol and triglyceride levels in AlCl3-induced AD zebrafish larvae. Our molecular docking results indicated that BC significantly interacted with the ABCA1 protein, suggesting that BC may act as an ABCA1 agonist. Based on our results, it can be concluded that BC may serve as an effective therapeutic agent for mitigating oxidative stress by altering cholesterol metabolism in AlCl3-induced AD.

Polyphenols and Their Biogenic Nano-Formulations Targeting BACE1 as Anti-Amyloid Therapies; Meeting the Challenges of Bioavailability, Safety, and Specificity for the Treatment of Alzheimer's Disease

Alzheimer's disease (AD), a progressiveneurodegenerative condition is marked by extensive damage in the brain and dementia. Among the pathological hallmarks of AD is beta-amyloid (Aβ). Production of toxic Aβ oligomers production and accumulation in the brain is among the characteristic features of the disease. The abnormal accumulation Aβ is initiated by the catalytic degradation of Amyloid Precursor Proteins (APP) by Beta Amyloid Cleaving Enzyme 1 (BACE1) to generate insoluble amyloid plaques. The abnormal proteins are mitochondrial poison which disrupt the energy production and liberate excessive free radicals causing neuronal damage and mutations. Consequently, targeting Aβ-associated pathways has become a focus in the pursuit of developing effective AD treatments. An obstacle faced by many medications used to treat neurodegenerative diseases (NDs) is the restricted permeability across the blood-brain barrier (BBB). Unfortunately, no anti-amyloid drug is clinically approved till now. Recent advancements in nanotechnology have provided a possible solution for delivering medications to specific targets. By integrating natural products with nano-medicinal approaches, it is possible to develop novel and highly efficient therapeutic strategies for the treatment of AD.

Modulation of cholesterol metabolism with Phytoremedies in Alzheimer's disease: A comprehensive review

Alzheimer's disease (AD) is a complex neurological ailment that causes cognitive decline and memory loss. Cholesterol metabolism dysregulation has emerged as a crucial element in AD pathogenesis, contributing to the formation of amyloid-beta (Aβ) plaques and tau tangles, the disease's hallmark neuropathological characteristics. Thus, targeting cholesterol metabolism has gained attention as a potential therapeutic method for Alzheimer's disease. Phytoremedies, which are generated from plants and herbs, have shown promise as an attainable therapeutic option for Alzheimer's disease. These remedies contain bioactive compounds like phytochemicals, flavonoids, and polyphenols, which have demonstrated potential in modulating cholesterol metabolism and related pathways. This comprehensive review explores the modulation of cholesterol metabolism by phytoremedies in AD. It delves into the role of cholesterol in brain function, highlighting disruptions observed in AD. Additionally, it examines the underlying molecular mechanisms of cholesterol-related pathology in AD. The review emphasizes the significance of phytoremedies as a potential therapeutic intervention for AD. It discusses the drawbacks of current treatments and the need for alternative strategies addressing cholesterol dysregulation and its consequences. Through an in-depth analysis of specific phytoremedies, the review presents compelling evidence of their potential benefits. Molecular mechanisms underlying phytoremedy effects on cholesterol metabolism are examined, including regulation of cholesterol-related pathways, interactions with Aβ pathology, influence on tau pathology, and anti-inflammatory effects. The review also highlights challenges and future perspectives, emphasizing standardization, clinical evidence, and personalized medicine approaches to maximize therapeutic potential in AD treatment. Overall, phytoremedies offer promise as a potential avenue for AD management, but further research and collaboration are necessary to fully explore their efficacy, safety, and mechanisms of action.

Therapeutic Effects of the major alkaloid constituents of Evodia rutaecarpa in Alzheimer's disease

Since the report of Alzheimer's disease (AD) in 1907, it has garnered widespread attention due to its intricate pathogenic mechanisms, significant impact on patients' lives, and the substantial burden it places on society. Presently, effective treatments for AD remain elusive. Recent pharmacological studies on the traditional East Asian herb, Evodia rutaecarpa, have revealed that the bioactive alkaloid components within it can ameliorate AD-related cognitive impairments and neurological damage through various pathways, including anti-inflammatory, antioxidant, and anti-acetylcholinesterase activities. Consequently, this article provides an overview of the pharmacological effects and research status of the four main alkaloid components found in Evodia concerning AD. We hope this article will serve as a valuable reference for experimental and clinical research on the use of Evodia in AD prevention and treatment.

Neuroprotective potentials of Lead phytochemicals against Alzheimer's disease with focus on oxidative stress-mediated signaling pathways: Pharmacokinetic challenges, target specificity, clinical trials and future perspectives

BACKGROUND

Alzheimer's diseases (AD) and dementia are among the highly prevalent neurological disorders characterized by deposition of beta amyloid (Aβ) plaques, dense deposits of highly phosphorylated tau proteins, insufficiency of acetylcholine (ACh) and imbalance in glutamatergic system. Patients typically experience cognitive, behavioral alterations and are unable to perform their routine activities. Evidence also suggests that inflammatory processes including excessive microglia activation, high expression of inflammatory cytokines and release of free radicals. Thus, targeting inflammatory pathways beside other targets might be the key factors to control- disease symptoms and progression.

PURPOSE

This review is aimed to highlight the mechanisms and pathways involved in the neuroprotective potentials of lead phytochemicals. Further to provide updates regarding challenges associated with their use and their progress into clinical trials as potential lead compounds.

METHODS

Most recent scientific literature on pre-clinical and clinical data published in quality journals especially on the lead phytochemicals including curcumin, catechins, quercetin, resveratrol, genistein and apigenin was collected using SciFinder, PubMed, Google Scholar, Web of Science, JSTOR, EBSCO, Scopus and other related web sources.

RESULTS

Literature review indicated that the drug discovery against AD is insufficient and only few drugs are clinically approved which have limited efficacy. Among the therapeutic options, natural products have got tremendous attraction owing to their molecular diversity, their safety and efficacy. Research suggest that natural products can delay the disease onset, reduce its progression and regenerate the damage via their anti-amyloid, anti-inflammatory and antioxidant potentials. These agents regulate the pathways involved in the release of neurotrophins which are implicated in neuronal survival and function. Highly potential lead phytochemicals including curcumin, catechins, quercetin, resveratrol, genistein and apigenin regulate neuroprotective signaling pathways implicated in neurotrophins-mediated activation of tropomyosin receptor kinase (Trk) and p75 neurotrophins receptor (p75NTR) family receptors.

CONCLUSIONS

Phytochemicals especially phenolic compounds were identified as highly potential molecules which ameliorate oxidative stress induced neurodegeneration, reduce Aβ load and inhibit vital enzymes. Yet their clinical efficacy and bioavailability are the major challenges which need further interventions for more effective therapeutic outcomes.

Bioassays guided isolation of berberine from Berberis lycium and its neuroprotective role in aluminium chloride induced rat model of Alzheimer's disease combined with insilico molecular docking

OBJECTIVE

Berberis lycium is an indigenous plant of Pakistan that is known for its medicinal properties. In the current study, we investigated the anti-Alzheimer's effect of berberine isolated from Berberis lycium.

METHODS

Root extract of B. lycium was subjected to acetylcholinesterase inhibition assay and column chromatography for bioassays guided isolation of a compound. The neuroprotective and memory improving effects of isolated compound were evaluated by aluminium chloride induced Alzheimer's disease rat model, elevated plus maze (EPM) and Morris water maze (MWM) tests., Levels of dopamine and serotonin in rats brains were determined using HPLC. Moreover, western blot and docking were performed to determine interaction between berberine and β-secretase.

RESULTS

During fractionation, ethyl acetate and methanol (3:7) fraction was collected from solvent mixture of ethyl acetate and methanol. This fraction showed the highest anti-acetylcholinesterase activity and was alkaloid positive. The results of TLC and HPLC analysis indicated the presence of the isolated compound as berberine. Additionally, the confirmation of isolated compound as berberine was carried out using FTIR and NMR analysis. In vivo EPM and MWM tests showed improved memory patterns after berberine treatment in Alzheimer's disease model. The levels of dopamine, serotonin and activity of antioxidant enzymes were significantly (p<0.05) enhanced in brain tissue homogenates of berberine treated group. This was supported by decreased expression of β-secretase in berberine treated rat brain homogenates and good binding affinity of berberine with β-secretase in docking studies. Binding energies for interaction of β-secretase with berberine and drug Rivastigmine is -7.0 kcal/mol and -5.8 kcal/mol respectively representing the strong interactions. The results of docked complex of secretase with berberine and Rivastigmine was carried out using Gromacs which showed significant stability of complex in terms of RMSD and radius of gyration. Overall, the study presents berberine as a potential drug against Alzheimer's disease by providing evidence of its effects in improving memory, neurotransmitter levels and reducing β-secretase expression in the Alzheimer's disease model.

Long term administration of loquat leaves and their major component, ursolic acid, attenuated endogenous amyloid-β burden and memory impairment

Loquat (Eriobotrya japonica) leaves contain many bioactive components such as ursolic acid (UA) and amygdalin. We investigated the effects of loquat leaf powder and methanol extract in human neuroglioma H4 cells stably expressing the Swedish-type APP695 (APPNL-H4 cells) and C57BL/6 J mice. Surprisingly, the extract greatly enhanced cellular amyloid-beta peptide (Aβ) 42 productions in APPNL-H4 cells. Administration of leaf powder increased Aβ42 levels after 3 months and decreased levels after 12 months compared to control mice. Leaf powder had no effect on working memory after 3 months, but improved working memory after 12 months. Administration of UA decreased Aβ42 and P-tau levels and improved working memory after 12 months, similar to the administration of leave powder for 12 months. Amygdalin enhanced cellular Aβ42 production in APPNL-H4 cells, which was the same as the extract. Three-month administration of amygdalin increased Aβ42 levels slightly but did not significantly increase them, which is similar to the trend observed with the administration of leaf powder for 3 months. UA was likely the main compound contained in loquat leaves responsible for the decrease in intracerebral Aβ42 and P-tau levels. Also, amygdalin might be one of the compounds responsible for the transiently increased intracerebral Aβ42 levels.

Update on new trends and progress of natural active ingredients in the intervention of Alzheimer's disease, based on understanding of traditional Chinese and Western relevant theories: A review

Alzheimer's disease (AD) is one of the major neurological disorders causing death in the elderly worldwide. As a neurodegenerative disease that is difficult to prevent and cure, the pathogenesis of AD is complex and there is no effective cure. A variety of natural products derived from plants have been reported to have promising anti-AD activities, including flavonoids, terpenes, phenolic acids and alkaloids, which can effectively relieve the symptoms of AD in a variety of ways. This paper mainly reviews the pharmacological activity and mechanisms of natural products against AD. Although the clinical efficacy of these plants still needs to be determined by further high-quality studies, it may also provide a basis for future researchers to study anti-AD in depth.

Network pharmacology reveals that Berberine may function against Alzheimer's disease via the AKT signaling pathway

Objective

To investigate the mechanism underlying the effects of berberine (BBR) in the treatment of Alzheimer's disease (AD).

Methods

3 × Tg AD mice were treated with BBR for 3 months, then the open field test (OFT), the novel object recognition test (NOR) and the Morris water maze (MWM) test were performed to assess behavioral performance. Hematoxylin-eosin (HE) staining, Nissl staining were used to examine histopathological changes. The pharmacological and molecular properties of BBR were obtained from the TCMSP database. BBR-associated AD targets were identified using the PharmMapper (PM), the comparative toxicogenomics database (CTD), DisGeNet and the human gene database (GeneCards). Core networks and BBR targets for the treatment of AD were identified using PPI network and functional enrichment analyses. AutoDock software was used to model the interaction between BBR and potential targets. Finally, RT-qPCR, western blotting were used to validate the expression of core targets.

Results

Behavioral experiments, HE staining and Nissl staining have shown that BBR can improve memory task performance and neuronal damage in the hippocampus of AD mice. 117 BBR-associated targets for the treatment of AD were identified, and 43 genes were used for downstream functional enrichment analysis in combination with the results of protein-protein interaction (PPI) network analysis. 2,230 biological processes (BP) terms, 67 cell components (CC) terms, 243 molecular function (MF) terms and 118 KEGG terms were identified. ALB, EGFR, CASP3 and five targets in the PI3K-AKT signaling pathway including AKT1, HSP90AA1, SRC, HRAS, IGF1 were selected by PPI network analysis, validated by molecular docking analysis and RT-q PCR as core targets for further analysis. Akt1 mRNA expression levels were significantly decreased in AD mice and significantly increased after BBR treatment (p < 0.05). Besides, AKT and ERK phosphorylation decreased in the model group, and BBR significantly increased their phosphorylation levels.

Conclusion

AKT1, HSP90AA1, SRC, HRAS, IGF1 and ALB, EGFR, CASP3 were core targets of BBR in the treatment of AD. BBR may exert a neuroprotective effect by modulating the ERK and AKT signaling pathways.

Multifaceted role of polyphenols in the treatment and management of neurodegenerative diseases

Neurodegenerative diseases (NDDs) are conditions that cause neuron structure and/or function to deteriorate over time. Genetic alterations may be responsible for several NDDs. However, a multitude of physiological systems can trigger neurodegeneration. Several NDDs, such as Huntington's, Parkinson's, and Alzheimer's, are assigned to oxidative stress (OS). Low concentrations of reactive oxygen and nitrogen species are crucial for maintaining normal brain activities, as their increasing concentrations can promote neural apoptosis. OS-mediated neurodegeneration has been linked to several factors, including notable dysfunction of mitochondria, excitotoxicity, and Ca2+ stress. However, synthetic drugs are commonly utilized to treat most NDDs, and these treatments have been known to have side effects during treatment. According to providing empirical evidence, studies have discovered many occurring natural components in plants used to treat NDDs. Polyphenols are often safer and have lesser side effects. As, epigallocatechin-3-gallate, resveratrol, curcumin, quercetin, celastrol, berberine, genistein, and luteolin have p-values less than 0.05, so they are typically considered to be statistically significant. These polyphenols could be a choice of interest as therapeutics for NDDs. This review highlighted to discusses the putative effectiveness of polyphenols against the most prevalent NDDs.

Deciphering the enigmatic crosstalk between prostate cancer and Alzheimer's disease: A current update on molecular mechanisms and combination therapy

Alzheimer's disease (AD) and prostate cancer (PCa) are considered the leading causes of death in elderly people worldwide. Although both these diseases have striking differences in their pathologies, a few underlying mechanisms are similar when cell survival is considered. In the current study, we employed an in-silico approach to decipher the possible role of bacterial proteins in the initiation and progression of AD and PCa. We further analyzed the molecular connections between these two life-threatening diseases. The androgen deprivation therapy used against PCa has been shown to promote castrate resistant PCa as well as AD. In addition, cell signaling pathways, such as Akt, IGF, and Wnt contribute to the progression of both AD and PCa. Besides, various proteins and genes are also common in disease progression. One such similarity is mTOR signaling. mTOR is the common downstream target for many signaling pathways and plays a vital role in both PCa and AD. Targeting mTOR can be a favorable line of treatment for both AD and PCa. However, drug resistance is one of the challenges in effective drug therapy. A few drugs that target mTOR have now become ineffective due to the development of resistance. In that regard, phytochemicals can be a rich source of novel drug candidates as they can act via multiple mechanisms. This review also presents mTOR targeting phytochemicals with promising anti-PCa, anti-AD activities, and approaches to overcome the issues associated with phytochemical-based therapies in clinical trials.

Berberine Ameliorates Cognitive Disorder via GSK3β/PGC-1α Signaling in APP/PS1 Mice

Previous studies have revealed that Berberine (BBR) had therapeutic effects on Alzheimer's disease (AD). However, the underlying mechanism of BBR in the treatment of AD is unclear. The study was to investigate whether berberine ameliorates cognitive disorder in AD by regulating on GSK3β/PGC-1α signaling pathway. APP/PS1 mice were treated with BBR (50 mg/kg and 100 mg/kg) for 4 mo, and the cognitive function of mice was tested by Morris water maze. The levels of inflammatory cytokines IL-1β, TNF-α, and IL-6 in hippocampus of mice were detected by ELISA kits. The damage of neuronal in hippocampal CA1 was detected by Nissl staining. The tau and GSK3β protein were detected by western blot. The results showed that BBR treatment obviously improved spatial cognitive function of APP/PS1 mice. Meanwhile, the pro-inflammatory cytokines were decreased in hippocampus by the administration of BBR. Additionally, BBR significantly alleviated neuronal damage and reduced the levels of hyperphosphorylated tau at sites of Thr205 and Thr231 in hippocampus. Importantly, BBR inhibited the activity of GSK3β and increased the expression of PGC-1α. Consequently, our results demonstrates that BBR could improve the cognitive function by inhibiting the tau hyperphosphorylation and neuroinflammation. These beneficial effects of BBR may be attributed to the regulation of GSK3β/PGC-1α signaling pathway in APP/PS1 mice. These findings reveal a vital role for GSK3β/PGC-1α signaling pathway in retarding cognitive disorder, indicating that PGC-1α might be a potential target for the treatment of AD.

Network Pharmacology-Based Strategy to Investigate the Pharmacologic Mechanisms of Coptidis Rhizoma for the Treatment of Alzheimer's Disease

Background

Alzheimer's disease (AD) is becoming a more prevalent public health issue in today's culture. The experimental study of Coptidis Rhizoma (CR) and its chemical components in AD treatment has been widely reported, but the principle of multi-level and multi-mechanism treatment of AD urgently needs to be clarified.

Objective

This study focuses on network pharmacology to clarify the mechanism of CR's multi-target impact on Alzheimer's disease.

Methods

The Phytochemical-compounds of CR have been accessed from the Traditional Chinese Medicine Database and Analysis Platform (TCMSP) and Symmap database or HPLC determination. The values of Oral Bioavailability (OB) ≥ 30% and Drug Like (DL) ≥ 0.18 or blood ingredient were used to screen the active components of CR; the interactive network of targets and compounds were constructed by STRING and Cytoscape platform, and the network was analyzed by Molecular Complex Detection (MCODE); Gene Ontology (GO) function, Kyoto Encyclopedia of Genes and Genomes Pathway (KEGG) and metabolic pathway enrichment of targets were carried out with Metascape, the Database for Annotation, Visualization and Integrated Discovery (DAVID) and MetaboAnalyst platform; Based on CytoHubba, the potential efficient targets were screened by Maximal Clique Centrality (MCC) and Degree, the correlation between potential efficient targets and amyloid β-protein (Aβ), Tau pathology was analyzed by Alzdata database, and the genes related to aging were analyzed by Aging Altas database, and finally, the core targets were obtained; the binding ability between ingredients and core targets evaluated by molecular docking, and the clinical significance of core targets was assessed with Gene Expression Omnibus (GEO) database.

Results

19 active components correspond to 267 therapeutic targets for AD, of which 69 is potentially effective; in module analysis, RELA, TRAF2, STAT3, and so on are the critical targets of each module; among the six core targets, RELA, MAPK8, STAT3, and TGFB1 have clinical therapeutic significance; GO function, including 3050 biological processes (BP), 257 molecular functions (MF), 184 cellular components (CC), whose functions are mainly related to antioxidation, regulation of apoptosis and cell composition; the HIF-1 signaling pathway, glutathione metabolism is the most significant result of 134 KEGG signal pathways and four metabolic pathways, respectively; most of the active components have an excellent affinity in docking with critical targets.

Conclusion

The pharmacological target prediction of CR based on molecular network pharmacology paves the way for a multi-level networking strategy. The study of CR in AD treatment shows a bright prospect for curing neurodegenerative diseases.

Protective effects of berberine on various kidney diseases: Emphasis on the promising effects and the underlined molecular mechanisms

Berberine (BBR) is a pentacyclic benzylisoquinoline alkaloid that can be found in diversity of medicinal plants. BBR has a wide range of pharmacological bioactivities, in addition when administrated orally, it has a broad safety margin. It has been used as an antidiarrheal, antimicrobial, and anti-diabetic drug in Ayurvedic and Chinese medicine. Several scholars have found that BBR has promising renoprotective effects against different renal illnesses, including diabetic nephropathy, renal fibrosis, renal ischemia, renal aging, and renal stones. Also, it has renoprotective effects against nephrotoxicity induced by chemotherapy, heavy metal, aminoglycosides, NSAID, and others. These effects imply that BBR has an evolving therapeutic potential against acute renal failure and chronic renal diseases. Hence, we report herein the beneficial therapeutic renoprotective properties of BBR, as well as the highlighted molecular mechanism. In conclusion, the studies discussed throughout this review will afford a comprehensive overview about renoprotective effect of BBR and its therapeutic impact on different renal diseases.

Lipid Nanocarriers Overlaid with Chitosan for Brain Delivery of Berberine via the Nasal Route

This research aimed to design, optimize, and evaluate berberine-laden nanostructured lipid carriers overlaid with chitosan (BER-CTS-NLCs) for efficient brain delivery via the intranasal route. The nanostructured lipid carriers containing berberine (BER-NLCs) were formulated via hot homogenization and ultrasonication strategy and optimized for the influence of a variety of causal variables, including the amount of glycerol monostearate (solid lipid), poloxamer 407 (surfactant) concentration, and oleic acid (liquid lipid) amount, on size of the particles, entrapment, and the total drug release after 24 h. The optimal BER-NLCs formulation was then coated with chitosan. Their diameter, in vitro release, surface charge, morphology, ex vivo permeability, pH, histological, and in vivo (pharmacokinetics and brain uptake) parameters were estimated. BER-CTS-NLCs had a size of 180.9 ± 4.3 nm, sustained-release properties, positive surface charge of 36.8 mV, and augmented ex-vivo permeation via nasal mucosa. The histopathological assessment revealed that the BER-CTS-NLCs system is safe for nasal delivery. Pharmacokinetic and brain accumulation experiments showed that animals treated intranasally with BER-CTS-NLCs had substantially greater drug levels in the brain. The ratios of BER brain/blood levels at 30 min, AUCbrain/AUCblood, drug transport percentage, and drug targeting efficiency for BER-CTS-NLCs (IN) were higher compared to BER solution (IN), suggesting enhanced brain targeting. The optimized nanoparticulate system is speculated to be a successful approach for boosting the effect of BER in treating CNS diseases, such as Alzheimer's disease, through intranasal therapy.

Tree Turmeric: A Super Food and Contemporary Nutraceutical of 21st Century - A Laconic Review

Since ancient times the medicinal plants have been under use as food and potential therapeutic agent for the management of overall health and the use of all plant parts including fruits, seeds, is well reported in the literature. One such plant is Berberis aristata which is rich in vitamins, minerals, and various phytochemicals amongst which Berberine is the principal bioactive compound with a range of reported health benefits, and some of the commercial formulations like Rasaut, Darvyadi Leha are being used for the treatments of jaundice, malaria, typhoid fever, inflammation, eye infection, diarrhea, wound healing, etc. The hepatoprotective, antidiabetic, antitumor, anti-cancerous, properties are the recent additions to its functional importance. Berberine has significant bioactivities in the treatments of different diseases. Besides its remarkable applications, the berberine has low efficacy due to its low solubility in water, poor absorption, and low bioavailability. This problem can be solved by using some techniques like Nanotechnology which has been found to increase its solubility in water, bioavailability, and absorption and hence provide a better delivery system of berberine. This review illuminates the therapeutic applications of the plant Berberis aristata, scientific validation to its traditional uses, role of berberine in the treatment of various diseases through its different bioactivities, major flaws in berberine treatment, and the role of nanotechnology in minimizing those flaws and increasing its overall efficacy. Key teaching pointsPlant Berberis aristata has been used since ancient times for the treatment of various ailments like jaundice, hepatitis, fever, bleeding, inflammation, diarrhea, malaria, skin and eye infections, chronic rheumatism, and urinary disorders.Berberine is the major and most significant phytochemical among numerous phytochemicals present in plant Berberis aristata.Berberine has significantly shown many potent effect against emerging diseases like cancer and diabetes. Besides that, it has also shown antioxidant, anti-inflamation, antimicrobial, hepatoprotective, and anti-gastrointestinal disorder properties.Berberine can be very effective in overcoming the demerits of berberine treatment like poor aqueous solubility, low bioavailability, and poor absorption in the human body in the treatment of various diseases.

Neuroprotective potential of berberine in modulating Alzheimer's disease via multiple signaling pathways

Berberine is one of the most important quinoline alkaloids, which has shown numerous pharmacological activities. There are pieces of evidence that berberine serves as a promising substance for treating Alzheimer's disease (AD). Recently, numerous studies on animal models have shown the neuroprotective role of berberine. AD is a complex disease having multiple pathological factors. Berberine restrains the deposition of amyloid plaques and neurofibrillary tangles. Substantial studies have demonstrated that berberine may also exhibit the protective effect against the risk factors associated with AD. This review illustrates the role of berberine in neuroinflammation, oxidative stress and its activity against acetylcholinesterase enzyme. It also focuses on the bioavailability and safety of berberine in AD. However, more investigations are required to explore the bioavailability and safety assessment of berberine and its new perspectives in limiting the AD-related pathogenesis and risk factors. PRACTICAL APPLICATIONS: Current therapeutic measures only provide symptomatic relief against AD by slowing memory loss, resolving thinking problems and behavioral issues. In recent past years, many biological actions and potential therapeutic applications have been observed by berberine particularly in neurological diseases. Berberine has been investigated by various researchers for its activity against AD. This review demonstrates a variety of mechanisms by which berberine imparts its neuroprotective roles and provides the possible mechanism of action of berberine by which it prevents the formation of neurofibrillary tangles and disaggregation of amyloid beta plaques in AD. It also focuses that berberine limits the neuroinflammation and oxidative stress in AD. Pre-clinical aspects of berberine against AD are also discussed. Eventually, a prospect is formulated that berberine might be a therapeutically significant agent for treating and preventing AD.

Selective Secretase Targeting for Alzheimer's Disease Therapy

Alzheimer's disease (AD) is associated with marked atrophy of the cerebral cortex and accumulation of amyloid plaques and neurofibrillary tangles. Amyloid plaques are formed by oligomers of amyloid-β (Aβ) in the brain, with a length of 42 and 40 amino acids. α-secretase cleaves amyloid-β protein precursor (AβPP) producing the membrane-bound fragment CTFα and the soluble fragment sAβPPα with neuroprotective activity; β-secretase produces membrane-bound fragment CTFβ and a soluble fragment sAβPPβ. After α-secretase cleavage of AβPP, γ-secretase cleaves CTFα to produce the cytoplasmic fragment AICD and P3 in the non-amyloidogenic pathway. CTFβ is cleaved by γ-secretase producing AICD as well as Aβ in amyloidogenic pathways. In the last years, the study of natural products and synthetic compounds, such as α-secretase activity enhancers, β-secretase inhibitors (BACE-1), and γ-secretase activity modulators, have been the focus of pharmaceuticals and researchers. Drugs were improved regarding solubility, blood-brain barrier penetration, selectivity, and potency decreasing Aβ42. In this regard, BACE-1 inhibitors, such as Atabecestat, NB-360, Umibecestat, PF-06751979 Verubecestat, LY2886721, Lanabecestat, LY2811376 and Elenbecestat, were submitted to phase I-III clinical trials. However, inhibition of Aβ production did not recover cognitive functions or reverse disease progress. Novel strategies are being developed, aiming at a partial reduction of Aβ production, such as the development of γ-secretase modulators or α-secretase activity enhancers. Such therapeutic tools shall focus on slowing down or minimizing the progression of neuronal damage. Here, we summarize structures and activities of the latest compounds designed for AD treatment, with remarkable in vitro, in vivo, and clinical phase activities.

A novel combined resveratrol/berberine phytochemotheraputic using the HePG2 cell line as a model for the treatment of hepatocarcinoma

The results presented herein show that at clinically relevant concentrations (0-30 µM), the well-tolerated phytochemical berberine (BER) induces cell death in cultured human hepatocarcinoma (HepG2) cells as a model for liver cancer, primarily via apoptosis. Similar, relatively low-concentration single treatments using the structurally related phytochemical resveratrol (RSV), had little or no effect on cell viability but inhibited the cell cycle, while simultaneously increasing the strength of cellular adhesion. When used in combination, an RSV/BER cotreatment appeared to retain the ability of a single RSV treatment to increase cellular adhesion, but also induced a massive loss in hepatocarcinoma cellular viability, inducing cell death in more than 90% of cells. This model, therefore, suggests that it may be possible to use RSV to stabilise hepatocarcinomas against metastasis while using cotreatment with BER to simultaneously induce cell death. By measuring the changes in the activity of the pleiotropic enzyme transglutaminase 2 (TGM2), which is known to be overexpressed in hepatocarcinoma and many other tumours, we hypothesise a role for this enzyme in the activities of these two phytochemicals, and propose the potential use of this RSV/BER cotreatment as a chemotherapeutic in TGM2+ hepatocarcinomas.

In vitro anthelmintic evaluation of three alkaloids against gastrointestinal nematodes of goats

This study assessed the in vitro anthelmintic activity of the alkaloids berberine, harmaline and piperine on gastrointestinal nematodes (GIN) of goat and their possible cytotoxic effects in Vero cells. The anthelmintic evaluation was performed using the egg hatch (EHA) and larval motility (LMA) assays. Cytotoxicity was determined using the 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyl-tetrazolium bromide (MTT) assay. The alkaloids berberine and piperine inhibited the hatching of GIN eggs in more than 90 %. Piperine was the most active compound against goat GIN eggs with an EC₅₀ (effective concentration 50 %) of 0.0074 mM (0.0021 mg/mL), while the EC₅₀ of berberine was 1.32 mM (0.49 mg/mL). Harmaline (EC₅₀ = 1.6 mM - 0.34 mg/mL) showed moderate ovicidal action (80.30 %). In LMA, piperine and harmaline reduced larval motility in 2.75 and 25.29 %, respectively. Larvicidal efficacy was evidenced only with the alkaloid berberine, which showed a percentage of inhibition of larval motility of 98.17 % (2.69 mM =1.0 mg/mL). In the MTT assay, all alkaloids showed low toxicity to Vero cells, with a percentage of cell viability greater than 50 % in all concentrations tested. These results suggest that berberine and piperine have anthelmintic potential on goat gastrointestinal nematodes with low toxicity to mammalian cells.

Therapeutic Potential of Phytoconstituents in Management of Alzheimer's Disease

Since primitive times, herbs have been extensively used in conventional remedies for boosting cognitive impairment and age-associated memory loss. It is mentioned that medicinal plants have a variety of dynamic components, and they have become a prominent choice for synthetic medications for the care of cognitive and associated disorders. Herbal remedies have played a major role in the progression of medicine, and many advanced drugs have already been developed. Many studies have endorsed practicing herbal remedies with phytoconstituents, for healing Alzheimer's disease (AD). All the information in this article was collated from selected research papers from online scientific databases, such as PubMed, Web of Science, and Scopus. The aim of this article is to convey the potential of herbal remedies for the prospect management of Alzheimer's and related diseases. Herbal remedies may be useful in the discovery and advancement of drugs, thus extending new leads for neurodegenerative diseases such as AD. Nanocarriers play a significant role in delivering herbal medicaments to a specific target. Therefore, many drugs have been described for the management of age-linked complaints such as dementia, AD, and the like. Several phytochemicals are capable of managing AD, but their therapeutic claims are restricted due to their lower solubility and metabolism. These limitations of natural therapeutics can be overcome by using a targeted nanocarrier system. This article will provide the primitive remedies as well as the development of herbal remedies for AD management.

Study on the mechanisms of the cross-resistance to TET, PIP, and GEN in Staphylococcus aureus mediated by the Rhizoma Coptidis extracts

The purpose of this study was focused on the mechanisms of the cross-resistance to tetracycline (TET), piperacillin Sodium (PIP), and gentamicin (GEN) in Staphylococcus aureus (SA) mediated by Rhizoma Coptidis extracts (RCE). The selected strains were exposed continuously to RCE at the sublethal concentrations for 12 days, respectively. The susceptibility change of the drug-exposed strains was determined by analysis of the minimum inhibitory concentration. The 16S rDNA sequencing method was used to identify the RCE-exposed strain. Then the expression of resistant genes in the selected isolates was analyzed by transcriptome sequencing. The results indicated that RCE could trigger the preferential cross-resistance to TET, PIP, and GEN in SA. The correlative resistant genes to the three kinds of antibiotics were upregulated in the RCE-exposed strain, and the mRNA levels of the resistant genes determined by RT-qPCR were consistent with those from the transcriptome analysis. It was suggested from these results that the antibacterial Traditional Chinese Medicines might be a significant factor of causing the bacterial antibiotic-resistance.

Exploring Potential of Alkaloidal Phytochemicals Targeting Neuroinflammatory Signaling of Alzheimer's Disease

Alzheimer's disease (AD) is a chronic neurodegenerative disorder that is marked by cognitive dysfunctions and the existence of neuropathological hallmarks such as amyloid plaques, and neurofibrillary tangles. It has been observed that a persistent immune response in the brain has appeared as another neuropathological hallmark in AD. The sustained activation of the microglia, the brain's resident macrophages, and other immune cells has been shown to aggravate both tau and amyloid pathology and may consider as a connection in the AD pathogenesis. However, the basic mechanisms that link immune responses in the pathogenesis of AD are unclear until now since the process of neuroinflammation can have either a harmful or favorable effect on AD, according to the phase of the disease. Numerous researches recommend that nutritional fruits, as well as vegetables, possess neurodefensive properties against the detrimental effects of neuroinflammation and aging. Moreover, these effects are controlled by diverse phytochemical compounds that are found in plants and demonstrate anti-inflammatory, neuroprotective, as well as other beneficial actions. In this review, we focus on the link of neuroinflammation in AD as well as highlight the probable mechanisms of alkaloidal phytochemicals to combat the neuroinflammatory aspect of AD.

Bioactive Compounds and Traditional Herbal Medicine: Promising Approaches for the Treatment of Dementia

Dementia is a term that encompasses a group of clinical symptoms affecting memory, thinking and social abilities, characterized by progressive impairment of memory performance and cognitive functions. There are several factors involved in the pathogenesis and progression of dementia, such as old age, brain ischemia, toxin exposure, and oxidative stress. There are extensive similarities between dementia and Alzheimer's disease (AD) either in clinical manifestations or experimental animal models. AD is the most dominant form of dementia, characterized by the accumulation of beta-amyloid protein and cholinergic neurotransmission deficits in the brain. Currently available medications for the treatment of dementia, such as choline esterase inhibitors, N-methyl-D-aspartate (NMDA) antagonists (memantine), have short-term efficacy and only relieve symptoms rather than targeting the main underlying pathogenesis. Several animal studies and clinical trials are being conducted to provide a rational approach to these medicinal plants in the prevention or treatment of memory deficits. This review highlights the potential effects of medicinal plants and their derived lead molecules, and explains the related mechanisms and effects reviewed from published literature as major thrust aspects and hopeful strategies in the prevention or treatment of dementia.

Effects of berberine on cholinesterases and monoamine oxidase activities, and antioxidant status in the brain of streptozotocin (STZ)-induced diabetic rats

OBJECTIVES

Several studies had been conducted to examine the link between diabetes and diabetes encephalopathy. This study was conducted to examine the potency of berberine (BER) on the restoration of impaired neurochemicals in the brain of streptozotocin (STZ)-induced diabetic Wistar rats.

METHODS

Fifty-six (56) adult rats weighing between 200 and 230 g were randomly divided into seven groups (n=8) as follows; Group I is normal control; Groups II and III were normal rats treated with 50 and 100 mg/kg respectively; Group IV-VII were STZ-induced rats, but Groups V-VII were treated with acarbose (25 mg/kg), 50 and 100 mg/kg of BER, respectively.

RESULTS

The result of the study showed that untreated STZ-induced diabetic rats have increased acetylcholinesterase (AChE), butyrylcholinesterase (BChE), monoamine oxidase (MAO) activities, and malonylaldehyde (MDA) level, with concomitant decrease of superoxide dismutase (SOD), glutathione peroxidase (GPx) activities, and glutathione (GSH) level. However, daily treatment with 50 and 100 mg/kg BER and ACA significantly reversed these effects.

CONCLUSIONS

The findings of this study clearly indicated that BER possesses neuro-protective and antioxidative potentials and normalize neurochemical impairment distort by diabetes.

Natural Products Targeting Amyloid Beta in Alzheimer's Disease

Alzheimer’s disease (AD) is a neurodegenerative disease characterized by severe brain damage and dementia. There are currently few therapeutics to treat this disease, and they can only temporarily alleviate some of the symptoms. The pathogenesis of AD is mainly preceded by accumulation of abnormal amyloid beta (Aβ) aggregates, which are toxic to neurons. Therefore, modulation of the formation of these abnormal aggregates is strongly suggested as the most effective approach to treat AD. In particular, numerous studies on natural products associated with AD, aiming to downregulate Aβ peptides and suppress the formation of abnormal Aβ aggregates, thus reducing neural cell death, are being conducted. Generation of Aβ peptides can be prevented by targeting the secretases involved in Aβ-peptide formation (secretase-dependent). Additionally, blocking the intra- and intermolecular interactions of Aβ peptides can induce conformational changes in abnormal Aβ aggregates, whereby the toxicity can be ameliorated (structure-dependent). In this review, AD-associated natural products which can reduce the accumulation of Aβ peptides via secretase- or structure-dependent pathways, and the current clinical trial states of these products are discussed.

In vitro and in silico studies of the larvicidal and anticholinesterase activities of berberine and piperine alkaloids on Rhipicephalus microplus

Rhipicephalus microplus is responsible for high economic losses in livestock and its control has become difficult due to the establishment of tick populations resistant to commercial acaricides. This study aimed to evaluate the in vitro larvicidal effect of the alkaloids berberine and piperine, and also to investigate their inhibitory mechanisms against the acetylcholinesterase enzyme. The effects of the alkaloids on larvae were observed through the immersion test at the following concentrations: 1.5; 3; 6; 12; 16 and 24 mM. Berberine and piperine presented larvicidal activity greater than 95 %, not differing from 100 % for the positive fipronil control (p > 0.05). Of the two alkaloids, piperine had a lower effective concentration (EC), with an EC₅₀ of 6.04 mM. The acetylcholinesterase enzyme used in the study was obtained from R. microplus larvae (RmAChE) and the anticholinesterase activity was determined spectrophotometrically. The highest anticholinesterase activity, measured as inhibition concentration (IC), was observed for berberine (IC50 = 88.13 μM), while piperine showed lower activity (IC50 > 200 μM). Docking studies in RmAChE, followed by 10 ns molecular dynamics simulation, suggest that berberine stabilizes the RmAChE at lower Root-Mean-Square Deviation (RMSD) than Apo protein. Few hydrogen-bond interactions between berberine and RmAChE residues were balanced by hydrophobic and π-type interactions. Berberine fills preferentially the peripheral anionic site (PAS), which correlates with its non-competitive mechanism. These results suggest that berberine and piperine alkaloids have an in vitro acaricidal action on R. microplus larvae, and the likely mechanism of action of berberine is related to RmAChE inhibition when accessing the PAS residues. These findings could help the study of new natural products that could inhibit RmAChE and aid in the development of new acaricides.

Discovery of natural alkaloids as potent and selective inhibitors against human carboxylesterase 2

Human Carboxylesterase 2A (hCES2A), one of the most important serine hydrolases, plays crucial roles in the hydrolysis and the metabolic activation of a wide range of esters and amides. Increasing evidence has indicated that potent inhibition on intestinal hCES2A may reduce the excessive accumulation of SN-38 (the hydrolytic metabolite of irinotecan with potent cytotoxicity) in the intestinal tract and thereby alleviate the intestinal toxicity triggered by irinotecan. In this study, more than sixty natural alkaloids have been collected and their inhibitory effects against hCES2A are assayed using a fluorescence-based biochemical assay. Following preliminary screening, seventeen alkaloids are found with strong to moderate hCES2A inhibition activity. Primary structure-activity relationships (SAR) analysis of natural isoquinoline alkaloids reveal that the benzo-1,3-dioxole group and the aromatic pyridine structure are beneficial for hCES2A inhibition. Further investigations demonstrate that a steroidal alkaloid reserpine exhibits strong hCES2A inhibition activity (IC₅₀ = 0.94 μM) and high selectivity over other human serine hydrolases including hCES1A, dipeptidyl peptidase IV (DPP-IV), butyrylcholinesterase (BChE) and thrombin. Inhibition kinetic analyses demonstrated that reserpine acts as a non-competitive inhibitor against hCES2A-mediated FD hydrolysis. Molecular docking simulations demonstrated that the potent inhibition of hCES2A by reserpine could partially be attributed to its strong σ-π and S-π interactions between reserpine and hCES2A. Collectively, our findings suggest that reserpine is a potent and highly selective inhibitor of hCES2A, which can be served as a promising lead compound for the development of more efficacious and selective alkaloids-type hCES2A inhibitors for biomedical applications.

α-Bisabolol, a Dietary Bioactive Phytochemical Attenuates Dopaminergic Neurodegeneration through Modulation of Oxidative Stress, Neuroinflammation and Apoptosis in Rotenone-Induced Rat Model of Parkinson's disease

Rotenone (ROT), a plant-derived pesticide is a well-known environmental neurotoxin associated with causation of Parkinson’s disease (PD). ROT impairs mitochondrial dysfunction being mitochondrial complex-I (MC-1) inhibitor and perturbs antioxidant-oxidant balance that contributes to the onset and development of neuroinflammation and neurodegeneration in PD. Due to the scarcity of agents to prevent the disease or to cure or halt the progression of symptoms of PD, the focus is on exploring agents from naturally occurring dietary phytochemicals. Among numerous phytochemicals, α-Bisabolol (BSB), natural monocyclic sesquiterpene alcohol found in many ornamental flowers and edible plants garnered attention due to its potent pharmacological properties and therapeutic potential. Therefore, the present study investigated the neuroprotective effects of BSB in a rat model of ROT-induced dopaminergic neurodegeneration, a pathogenic feature of PD and underlying mechanism targeting oxidative stress, inflammation and apoptosis. BSB treatment significantly prevented ROT-induced loss of dopaminergic neurons and fibers in the substantia nigra and striatum respectively. BSB treatment also attenuated ROT-induced oxidative stress evidenced by inhibition of MDA formation and GSH depletion as well as improvement in antioxidant enzymes, SOD and catalase. BSB treatment also attenuated ROT-induced activation of the glial cells as well as the induction and release of proinflammatory cytokines (IL-1β, IL-6 and TNF-α) and inflammatory mediators (iNOS and COX-2) in the striatum. In addition to countering oxidative stress and inflammation, BSB also attenuated apoptosis of dopaminergic neurons by attenuating downregulation of anti-apoptotic protein Bcl-2 and upregulation of pro-apoptotic proteins Bax, cleaved caspases-3 and 9. Further, BSB was observed to attenuate mitochondrial dysfunction by inhibiting mitochondrial lipid peroxidation, cytochrome-C release and reinstates the levels/activity of ATP and MC-I. The findings of the study demonstrate that BSB treatment salvaged dopaminergic neurons, attenuated microglia and astrocyte activation, induction of inflammatory mediators, proinflammatory cytokines and reduced the expression of pro-apoptotic markers. The in vitro study on ABTS radical revealed the antioxidant potential of BSB. The results of the present study are clearly suggestive of the neuroprotective effects of BSB through antioxidant, anti-inflammatory and anti-apoptotic properties in ROT-induced model of PD.

Network pharmacology-based strategy to investigate pharmacological mechanisms of Tinospora sinensis for treatment of Alzheimer's disease

ETHNOPHARMACOLOGICAL RELEVANCE

Tinospora sinensis (Lour.) Merr. belongs to the family Menispermaceae. It is called LeZhe and is widely used as a kind of folk medicine especially in the Tibetan Plateau of China. T. sinensis has the functions of clearing away heat and detoxification, dispelling wind and dredging collaterals, calming and soothing the nerves. T. sinensis is an effective medicine for the prevention and treatment of aging diseases such as Alzheimer's disease (AD) in the Tibetan Plateau of China, whereas its material basis and underlying mechanisms are not clear. The aim of this study was to investigate the material basis and potential mechanisms of T. sinensis in the treatment of AD by using network pharmacology and molecular docking.

MATERIALS AND METHODS

In this study, targets were collected from DrugBank database, Therapeutic Target Database (TTD) and literatures reports for the treatment of AD. Compounds were searched by literatures and systematic separation from T. sinensis. The molecular docking experiment was carried out by using Autodock Vina software to screen the bioactive compounds in T. sinensis and target proteins for AD. Then, the "compound-target network" was constructed by Cytoscape software. The drug-like properties of the active compounds were analyzed by pKCSM performs, and the protein-protein interaction (PPI) network was constructed by Search Tool for the Retrieval of Interacting Genes/Proteins (STRING). The Kyoto Encyclopedia of Genes and Genomes (KEGG) target pathway enrichment analysis was carried out by Database for Annotation, Visualization and Integrated Discovery (DAVID). Furthermore, the protective effect of neurons of two active compounds were verified with the injury cell model of PC12 and primary hippocampus neurons induced by Aβ_25-35. Finally, the key proteins of related pathways were quantitatively analyzed with Western blot method.

RESULTS

In total, 105 compounds and 38 targets have been screened. The main active compounds contained berberine, which belongs to alkaloids, Aurantiamide acetate, N-P-coumaroyltyramine, which belongs to amides, Trans-syringin and 3-demethyl-phillyrin, which belongs to phenylpropanoids. The targets covered inflammation-related proteins, including Protein kinase B (AKT), Phosphoinositide 3-kinase (PI3K), Tyrosine-protein kinase JAK1 (JAK1), mammalian target of rapamycin (mTOR), tumor necrosis factor alpha (TNF-α), Neuronal NOS (NOS1), and cholinergic function-related proteins, including α4-Nicotinic acetylcholine receptor (α4 nAChR), Muscarinic acetylcholine receptor M1 (Muscarnic M1). Inflammation and cholinergic dysfunction were the center of the network and occupy a dominant position. And the results of enrichment analysis shown the pathways mainly contained phosphoinositide-3-kinase/Akt (PI3K/Akt) signal pathway, neurotrophic factors (NTFs) signal pathway, Hypoxia-inducible factor 1 (HIF-1) signal pathway, mechanistic Target of Rapamycin (mTOR) signal pathway, Tumor necrosis factor (TNF) signal pathway, insulin resistance (IR). The results of in vitro assays showed that the tested compounds could significantly improve the survival rate and inhibit the apoptosis of PC12 cells and primary hippocampal neurons injured by Aβ_25-35. Western blot results showed that T. sinensis had a significant effect on the expression of protein PI3K and Akt.

CONCLUSION

Our results revealed that T. sinensis could prevent and treat AD through a multi-compound-multi-target-multi-pathway regulatory network. Our work also expected to provide new ideas and theoretical bases for searching for the active compounds in T. sinensis and potential mechanism in the prevention and treatment of AD by the network pharmacology and molecular docking. The results of in vitro assay and in vivo assay supported the results of molecular docking.

Boosting the autophagy-lysosomal pathway by phytochemicals: A potential therapeutic strategy against Alzheimer's disease

The lysosome is a membrane-enclosed organelle in eukaryotic cells, which has basic pattern recognition for nutrient-dependent signal transduction. In Alzheimer's disease, the already declining autophagy-lysosomal function is exacerbated by an increased need for clearance of damaged proteins and organelles in aged cells. Recent evidence suggests that numerous diseases are linked to impaired autophagy upstream of lysosomes. In this way, a comprehensive survey on the pathophysiology of the disease seems necessary. Hence, in the first section of this review, we will discuss the ultimate findings in lysosomal signaling functions and how they affect cellular metabolism and trafficking under neurodegenerative conditions, specifically Alzheimer's disease. In the second section, we focus on how natural products and their derivatives are involved in the regulation of inflammation and lysosomal dysfunction pathways, including how these should be considered a crucial target for Alzheimer's disease therapeutics.

Beta-Blockers and Berberine: A Possible Dual Approach to Contrast Neuroblastoma Growth and Progression

The use of nutraceuticals during cancer treatment is a long-lasting debate. Berberine (BBR) is an isoquinoline quaternary alkaloid extracted from a variety of medicinal plants. BBR has been shown to have therapeutic effects in different pathologies, particularly in cancer, where it affects pathways involved in tumor progression. In neuroblastoma, the most common extracranial childhood solid tumor, BBR, reduces tumor growth by regulating both stemness and differentiation features and by inducing apoptosis. At the same time, the inhibition of β-adrenergic signaling leads to a reduction in growth and increase of differentiation of neuroblastoma. In this review, we summarize the possible beneficial effects of BBR in counteracting tumor growth and progression in various types of cancer and, in particular, in neuroblastoma. However, BBR administration, besides its numerous beneficial effects, presents a few side effects due to inhibition of MAO A enzyme in neuroblastoma cells. Therefore, herein, we proposed a novel therapeutic strategy to overcome side effects of BBR administration consisting of concomitant administration of BBR together with β-blockers in neuroblastoma.

Discovery of novel berberine derivatives with balanced cholinesterase and prolyl oligopeptidase inhibition profile

Berberine, a naturally occurring compound, possesses an interesting multipotent pharmacological profile potentially applicable for Alzheimer's disease (AD) treatment. In this study, a series of novel 22 berberine derivatives was developed and tested in vitro. Berberine core was substituted at position 9-O of its aromatic ring region. All the hybrids under the study revealed multi-targeted profile inhibiting prolyl oligopeptidase, acetylcholinesterase and butyrylcholinesterase highlighting 4a, 4g, 4j, 4l and 4s possessing balanced activities in the micromolar range. The top-ranked candidates in terms of the most pronounced potency against POP, AChE and BChE can be classified as 4d, 4u and 4v, bearing 4-methylbenzyl, (naphthalen-2-yl)methylene and 1-phenoxyethyl moieties, respectively. In vitro data were corroborated by detailed kinetic analysis of the selected lead molecules. 4d, 4u and 4v were also inspected for their potential to inhibit aggregation of two abberant proteins in AD, namely amyloid beta and tau, indicating their potential disease-modifying properties. To explain the results of our study, we carried out docking simulation to the active sites of the respective enzyme with the best berberine derivatives, along with QSAR study. We also investigated compounds' potential permeability through blood-brain barrier by applying parallel artificial membrane permeation assay and addressed their cytotoxicity profile.

Berberine: A Plant-derived Alkaloid with Therapeutic Potential to Combat Alzheimer's disease

Berberine (a protoberberine isoquinoline alkaloid) has shown promising pharmacological activities, including analgesic, anti-inflammatory, anticancer, antidiabetic, anti-hyperlipidemic, cardioprotective, memory enhancement, antidepressant, antioxidant, anti-nociceptive, antimicrobial, anti- HIV and cholesterol-lowering effects. It is used in the treatment of the neurodegenerative disorder. It has strong evidence to serve as a potent phytoconstituent in the treatment of various neurodegenerative disorders such as AD. It limits the extracellular amyloid plaques and intracellular neurofibrillary tangles. It has also lipid-glucose lowering ability, hence can be used as a protective agent in atherosclerosis and AD. However, more detailed investigations along with safety assessment of berberine are warranted to clarify its role in limiting various risk factors and AD-related pathologies. This review highlights the pharmacological basis to control oxidative stress, neuroinflammation and protective effect of berberine in AD, which will benefit to the biological scientists in understanding and exploring the new vistas of berberine in combating Alzheimer's disease.

The Secretion from Bone Marrow Mesenchymal Stem Cells Pretreated with Berberine Rescues Neurons with Oxidative Damage Through Activation of the Keap1-Nrf2-HO-1 Signaling Pathway

Oxidative stress is a potential pathological mechanism of Alzheimer's disease (AD). Berberine (BBR) can improve antioxidative capacity and inhibit Aβ protein aggregation and tau protein hyperphosphorylation in AD, and stem cell therapy is also increasingly recognized as a therapy for AD. Bone marrow mesenchymal stem cells (BMSCs) have many advantages, as they exhibit antioxidant and anti-inflammatory activity and secrete a variety of neurotrophic factors, and play important roles in neurodegenerative disease treatment. In this study, we investigated the antioxidant effects of secretions from BMSCs pretreated with BBR on tert-butyl hydroperoxide (t-BHP)-damaged neurons. We demonstrated that BBR can enhance BMSC viability and the secretion of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), both of which are vital neurotrophic factors that maintain neuronal growth. Moreover, conditioned medium from BBR-treated BMSCs (BBR-BMSC-CM) reduced reactive oxygen species (ROS) production, attenuated a decrease in the mitochondrial membrane potential, and ameliorated neuronal apoptosis by decreasing levels of the apoptotic proteins Bax/Bcl-2, cytochrome c, and cleaved caspase-3/caspase-3. In addition, increased synaptophysin (SYP) and postsynaptic density protein 95 (PSD95) levels indicated that neuronal synaptic function was restored. Further study revealed that BBR-BMSC-CM activated the antioxidant proteins Keap1, Nrf2, and HO-1. In conclusion, our results showed that BBR-BMSC-CM attenuated apoptosis and oxidative damage in neurons by activating the Keap1-Nrf2-HO-1 signaling pathway. Taken together, these results also suggest BBR as a drug to stimulate the secretion of nutritional cytokines with the potential to treat AD.

Galectin 3-binding protein suppresses amyloid-β production by modulating β-cleavage of amyloid precursor protein

Alzheimer's disease (AD) is the most common type of dementia, and its pathogenesis is associated with accumulation of β-amyloid (Aβ) peptides. Aβ is produced from amyloid precursor protein (APP) that is sequentially cleaved by β- and γ-secretases. Therefore, APP processing has been a target in therapeutic strategies for managing AD; however, no effective treatment of AD patients is currently available. Here, to identify endogenous factors that modulate Aβ production, we performed a gene microarray–based transcriptome analysis of neuronal cells derived from human induced pluripotent stem cells, because Aβ production in these cells changes during neuronal differentiation. We found that expression of the glycophosphatidylinositol-specific phospholipase D1 (GPLD1) gene is associated with these changes in Aβ production. GPLD1 overexpression in HEK293 cells increased the secretion of galectin 3–binding protein (GAL3BP), which suppressed Aβ production in an AD model, neuroglioma H4 cells. Mechanistically, GAL3BP suppressed Aβ production by directly interacting with APP and thereby inhibiting APP processing by β-secretase. Furthermore, we show that cells take up extracellularly added GAL3BP via endocytosis and that GAL3BP is localized in close proximity to APP in endosomes where amyloidogenic APP processing takes place. Taken together, our results indicate that GAL3BP may be a suitable target of AD-modifying drugs in future therapeutic strategies for managing AD.

Phytochemicals against TNFα-Mediated Neuroinflammatory Diseases

Tumor necrosis factor-alpha (TNF-α) is a well-known pro-inflammatory cytokine responsible for the modulation of the immune system. TNF-α plays a critical role in almost every type of inflammatory disorder, including central nervous system (CNS) diseases. Although TNF-α is a well-studied component of inflammatory responses, its functioning in diverse cell types is still unclear. TNF-α functions through its two main receptors: tumor necrosis factor receptor 1 and 2 (TNFR1, TNFR2), also known as p55 and p75, respectively. Normally, the functions of soluble TNF-α-induced TNFR1 activation are reported to be pro-inflammatory and apoptotic. While TNF-α mediated TNFR2 activation has a dual role. Several synthetic drugs used as inhibitors of TNF-α for diverse inflammatory diseases possess serious adverse effects, which make patients and researchers turn their focus toward natural medicines, phytochemicals in particular. Phytochemicals targeting TNF-α can significantly improve disease conditions involving TNF-α with fewer side effects. Here, we reviewed known TNF-α inhibitors, as well as lately studied phytochemicals, with a role in inhibiting TNF-α itself, and TNF-α-mediated signaling in inflammatory diseases focusing mainly on CNS disorders.

Berberine Protects C17.2 Neural Stem Cells From Oxidative Damage Followed by Inducing Neuronal Differentiation

Neurodegeneration is the loss of structure and/or function of neurons. Oxidative stress has been suggested as one of the common etiology in most of the neurodegenerative diseases. Previous studies have demonstrated the beneficial effects of berberine in various neurodegenerative and neuropsychiatric disorders. In this study, we hypothesized that berberine could protect C17.2 neural stem cells (NSCs) from 2,2′-Azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative damage then promote neuronal differentiation. AAPH was used to induce oxidative damage. After the damage, berberine protected C17.2 cells were kept cultured for another week in differentiation medium with/without berberine. Changes in cell morphology were detected by microscopy and cell viability was determined by MTT assay. Real-time PCR and western blot analysis were performed to confirm the associated pathways. Berberine was able to protect C17.2 NSCs from the oxidative damage. It lowered the cellular reactive oxygen species (ROS) level in C17.2 cells via Nuclear Factor Erythroid 2-Related Factor 1/2 (NRF1/2) – NAD(P)H Quinone Dehydrogenase 1 (NQO-1) – Heme Oxygenase 1 (HO-1) pathway. It also down-regulated the apoptotic factors-Caspase 3 and Bcl2 Associated X (Bax) and upregulated the anti-apoptotic factor-Bcl2 to reduce cell apoptosis. Besides, berberine increased C17.2 cell viability via up-regulating Extracellular-signal-Related Kinase (ERK) and phosphor-Extracellular-signal-Related Kinase (pERK) expression. Then, berberine promoted C17.2 cell to differentiate into neurons and the differentiation mechanism involved the activation of WNT/β-catenin pathway as well as the upregulation of expression levels of pro-neural factors Achaete-Scute Complex-Like 1 (ASCL1), Neurogenin 1 (NeuroG1), Neuronal Differentiation 2 (NeuroD2) and Doublecortin (DCX). In conclusion, berberine protected C17.2 NSCs from oxidative damage then induced them to differentiate into neurons.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) in Alzheimer's disease: A genetic and proteomic multi-cohort study

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a hepatic enzyme that regulates circulating low-density lipoprotein (LDL) cholesterol levels by binding to LDL receptors (LDLR) and promoting their degradation. Although PCSK9 inhibitors were shown to reduce the risk of cardiovascular disease, a warning was issued concerning their possible impact on cognitive functions. In Alzheimer's disease (AD), it is believed that cognitive impairment is associated with cholesterol metabolism alterations, which could involve PCSK9. The main objective of this study is to determine if PCSK9 plays a significant role in the pre-symptomatic phase of the disease when the pathophysiological markers of AD unfolds and, later, when cognitive symptoms emerge.

METHODS AND FINDINGS

To test if PCSK9 is associated with AD pathology, we measured its expression levels in 65 autopsy confirmed AD brains and 45 age and gender matched controls. Messenger ribonucleic acid (mRNA) were quantified using real-time polymerase chain reaction (RT-PCR) and protein levels were quantified using enzyme-linked immunosorbent assay (ELISA). PCSK9 was elevated in frontal cortices of AD subjects compared to controls, both at the mRNA and protein levels. LDLR protein levels were unchanged in AD frontal cortices, despite and upregulation at the mRNA level. To verify if PCSK9 dysregulation was observable before the onset of AD, we measured its expression in the cerebrospinal fluid (CSF) of 104 "at-risk" subjects and contrasted it with known apolipoproteins levels and specific AD biomarkers using ELISAs. Positive correlations were found between CSF PCSK9 and apolipoprotein E (APOE), apolipoprotein J (APOJ or CLU), apolipoprotein B (APOB), phospho Tau (pTau) and total Tau. To investigate if PCSK9 levels were driven by genetic variants, we conducted an expression quantitative trait loci (eQTL) study using bioinformatic tools and found two polymorphisms in strong association. Further investigation of these variants in two independent cohorts showed a female specific association with AD risk and with CSF Tau levels in cognitively impaired individuals.

CONCLUSIONS

PCSK9 levels differ between control and AD brains and its protein levels correlate with those of other lipoproteins and AD biomarkers even before the onset of the disease. PCSK9 regulation seems to be under tight genetic control in females only, with specific variants that could predispose to increased AD risk.

Nigella sativa and thymoquinone attenuate oxidative stress and cognitive impairment following cerebral hypoperfusion in rats

Nigella sativa, a plant widely used in traditional medicine, possesses anti-inflammatory, antioxidant and neuroprotective properties. In the present study, we investigated the effect of hydroalcoholic extract of N. sativa seeds (NSE) and its active constituent, thymoquinone (TQ), on learning and memory deficits, hippocampal acetylcholine esterase (AChE) activity, and markers of redox status, mainly lipid peroxidation and superoxide dismutase (SOD) activity following cerebral hypoperfusion in rats. Cerebral hypoperfusion was induced by permanent occlusion of bilateral common carotid arteries (2VO). Male Wistar rats were administered either a vehicle (sham group: 10 ml/kg/day, ip), NSE (100, 200, and 400 mg/kg/day, ip), TQ (10, 20, and 40 mg/kg/day, ip), or donepezil (5 mg/kg/day, ip) for 10 days (three days before and seven days after ligation). Spatial learning and memory deficits were investigated using the Morris water maze (MWM) task. 2VO produced significant learning and memory deficits as evidenced by increased latency time to reach the hidden platform, increased swimming time, and decreased time spent in the target quadrant in the probe trial in the MWM task. There was also a significant increase in the lipid peroxidation level and AChE activity, and a significant decrease in SOD activity in the hippocampal portion of hypoperfused rats, as compared with the sham group. Treatment with NSE (400 mg/kg/day; p < 0.001) and TQ (40 mg/kg/day; p < 0.001), as well as donepezil significantly prevented learning and memory impairments and alleviated changes in the hippocampal lipid peroxide level and SOD and AChE activities in this model. In conclusion, our data suggest that N. sativa and thymoquinone have a beneficial role in cerebrovascular insufficiency states and dementia.