Combating Neurodegenerative Diseases with the Plant Alkaloid Berberine: Molecular Mechanisms and Therapeutic Potential

Neuroprotective efficacy of berberine and caffeine against rotenone-induced neuroinflammatory and oxidative disturbances associated with Parkinson's disease via inhibiting α-synuclein aggregation and boosting dopamine release

Parkinson's disease (PD) is characterized by motor impairment, glial-mediated inflammation, redox imbalance, and α-synuclein (α-syn) aggregation. Conventional therapies relieve early PD symptoms, but they do not repair dopaminergic neurons. Berberine (BBR) and caffeine (CAF), both natural alkaloids, exhibited neuroprotective effects in many neurodegenerative disorders. Consequently, we hypothesized that the combination of BBR and CAF therapies would offer protection against PD-related impairments in the rotenone (ROT)-induced rat model when compared to the commercial drug, metformin (MTF). Our results showed that the combined administration of BBR (25 mg/kg/day) and CAF (2.5 mg/kg/day) for four weeks prevented motor deficits, weight reduction, dopamine (DA) depletion, and monoamine oxidase (MAO) activity in ROT-induced rats in comparison with monotherapy of BBR and CAF along with MTF. This combination produced a notable neuroprotective effect by reducing tumor necrosis factor (TNF)-α and interleukin-16 (IL-6) in midbrain of rats. BBR and CAF combinations markedly normalized tyrosine hydroxylase (TH) levels and decreased total α-syn and α-syn-pser129 aggregation and increased protein phosphatase 2A (PP2A) levels. Histological analysis indicated that damaged neurons exhibited significant amelioration with the co-administration of BBR and CAF. The molecular docking results indicated that both BBR and CAF had notable binding affinity for the protein pocket surrounding the α-syn, PP2A, and TH in comparison to MTF. They are predicted to serve as effective inhibitors of enzyme-mediated phosphorylation of α-syn-pser129. Conclusively, combined BBR and CAF administration presents a novel strategy for neuroprotection by blocking the initial events in PD incidence, demonstrating considerable anti-oxidative and anti-inflammatory benefits relative to MTF.

Key epigenetic enzymes modulated by natural compounds contributes to tumorigenicity

Dysregulation of epigenetic regulation is observed in numerous tumor cells. The therapeutic effects of natural products on tumors were investigated through a comprehensive analysis of active ingredients derived from various structured natural products. The analysis focuses on regulating key enzymes involved in epigenetic control. To study the modulation of these enzymes for tumor treatment, the structural characteristics of natural products that impact tumorigenesis were identified. The presence of specific patterns suggests that compounds sharing structural similarities can potentially induce therapeutic effects on identical tumors through modulation of distinct modifying enzymes. Structurally analogous natural products can likewise achieve therapeutic effects across diverse tumor types via their interaction with a common epigenetic enzyme. There exist numerous flavonoids with the capability to modulate METTL3, thereby influencing the development of various tumors. The normalization process was implemented to account for a common phenomenon, wherein structurally distinct compounds effectively target the same tumor by modulating a shared key enzyme. By summarizing, valuable insights into the role of compound-epigenetic enzymes in tumor development have been obtained. This discovery establishes a crucial scientific foundation for the prevention and treatment of tumor development through the utilization of structurally similar natural active ingredients.

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.

Network pharmacology study on the mechanism of berberine in Alzheimer's disease model

Research indicated that berberine (BBR) plays a protective role in modulating Alzheimer's disease (AD). This study aimed to explore the target genes of BBR associated with AD therapy using a network pharmacology study. Through network pharmacology analysis, two main potential target genes, β-amyloid precursor protein (APP) and peroxisome proliferator-activated receptor gamma (PPARG), of BBR for AD therapy were screened out. Further experiments demonstrated that BV2 and C8-D1A treated with BBR were decreased in the mRNA and protein expression of APP and presenilin 1 while PPARG was increased with a reduction in the NF-κB pathway. A similar result was shown in vivo. Through a network pharmacology study, this study supported that BBR played a protective role in the AD mice model via blocking APP processing and amyloid plaque formation. It also promotes PPARG expression to blockage of NF-κB pathway-mediated inflammatory response and neuroinflammation.

Berberine chloride loaded nano-PEGylated liposomes attenuates imidacloprid-induced neurotoxicity by inhibiting NLRP3/Caspase-1/GSDMD-mediated pyroptosis

Concerns have been expressed about imidacloprid (IMI), one of the most often used pesticides, and its potential neurotoxicity to non-target organisms. Chronic neuroinflammation is central to the pathology of several neurodegenerative disorders. Hence, exploring the molecular mechanism by which IMI would trigger neuroinflammation is particularly important. This study examined the neurotoxic effects of oral administration of IMI (45 mg/kg/day for 30 days) and the potential neuroprotective effect of berberine (Ber) chloride loaded nano-PEGylated liposomes (Ber-Lip) (10 mg/kg, intravenously every other day for 30 days) using laboratory rat. The histopathological changes, anti-oxidant and oxidative stress markers (GSH, SOD, and MDA), proinflammatory cytokines (IL1β and TNF-α), microglia phenotype markers (CD86 and iNOS for M1; CD163 for M2), the canonical pyroptotic pathway markers (NLRP3, caspase-1, GSDMD, and IL-18) and Alzheimer's disease markers (Neprilysin and beta amyloid [Aβ] deposits) were assessed. Oral administration of IMI resulted in apparent cerebellar histopathological alterations, oxidative stress, predominance of M1 microglia phenotype, significantly upregulated NLRP3, caspase-1, GSDMD, IL-18 and Aβ deposits and significantly decreased Neprilysin expression. Berberine reduced the IMI-induced aberrations in the measured parameters and improved the IMI-induced histopathological and ultrastructure alterations brought on by IMI. This study highlights the IMI neurotoxic effect and its potential contribution to the development of Alzheimer's disease and displayed the neuroprotective effect of Ber-Lip.

Revealing the potential therapeutic mechanism of Lonicerae Japonicae Flos in Alzheimer's disease: a computational biology approach

Background

Alzheimer's disease (AD) is a degenerative brain disease without a cure. Lonicerae Japonicae Flos (LJF), a traditional Chinese herbal medicine, possesses a neuroprotective effect, but its mechanisms for AD are not well understood. This study aimed to investigate potential targets and constituents of LJF against AD.

Methods

Network pharmacology and bioinformatics analyses were performed to screen potential compounds and targets. Gene Expression Omnibus (GEO) datasets related to AD patients were used to screen core targets of differential expression. Gene expression profiling interactive analysis (GEPIA) was used to validate the correlation between core target genes and major causative genes of AD. The receiver operating characteristic (ROC) analysis was used to evaluate the predictive efficacy of core targets based on GEO datasets. Molecular docking and dynamics simulation were conducted to analyze the binding affinities of effective compounds with core targets.

Results

Network pharmacology analysis showed that 112 intersection targets were identified. Bioinformatics analysis displayed that 32 putative core targets were identified from 112 intersection targets. Only eight core targets were differentially expressed based on GEO datasets. Finally, six core targets of MAPK8, CTNNB1, NFKB1, EGFR, BCL2, and NFE2L2 were related to AD progression and had good predictive ability based on correlation and ROC analyses. Molecular docking and dynamics simulation analyses elucidated that the component of lignan interacted with EGFR, the component of β-carotene interacted with CTNNB1 and BCL2, the component of β-sitosterol interacted with BCL2, the component of hederagenin interacted with NFKB1, the component of berberine interacted with EGFR and BCL2, and the component of baicalein interacted with NFKB1, EGFR and BCL2.

Conclusion

Through a comprehensive analysis, this study revealed that six core targets (MAPK8, CTNNB1, NFKB1, EGFR, BCL2, and NFE2L2) and six practical components (lignan, β-carotene, β-sitosterol, hederagenin, berberine, and baicalein) were involved in the mechanism of action of LJF against AD. Our work demonstrated that LJF effectively treats AD through its multi-component and multi-target properties. The findings of this study will establish a theoretical basis for the expanded application of LJF in AD treatment and, hopefully, can guide more advanced experimental research in the future.

Progress of Exosomal MicroRNAs and Traditional Chinese Medicine Monomers in Neurodegenerative Diseases

Exosomes, extracellular vesicles secreted by various cells, actively participate in intercellular communication by facilitating the exchange of crucial molecular information such as DNA, RNA, and lipids. Within this intricate network, microRNAs, endogenous non-coding small RNAs, emerge as pivotal regulators of post-transcriptional gene expression, significantly influencing the development of neurodegenerative diseases. The historical prominence of traditional Chinese medicine (TCM) in clinical practice in China underscores its enduring significance. Notably, TCM monomers, serving as active constituents within herbal medicine, assume a critical role in the treatment of neurodegenerative diseases, particularly in mitigating oxidative stress, inhibiting apoptosis, and reducing inflammation. This comprehensive review aims to delineate the specific involvement of exosomal microRNAs in various neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, stroke, and amyotrophic lateral sclerosis. Furthermore, the exploration extends to the application of TCM monomers, elucidating their efficacy as therapeutic agents in these conditions. Additionally, the review examines the utilization of exosomes as drug delivery carriers in the context of neurodegenerative diseases, providing a nuanced understanding of the potential synergies between TCM and modern therapeutic approaches. This synthesis of knowledge aims to contribute to the advancement of our comprehension of the intricate molecular mechanisms underlying neurodegeneration and the potential therapeutic avenues offered by TCcom interventions.

Neuroprotective effect and preparation methods of berberine

Berberine (BBR) is a natural alkaloid, which has played an important role in the field of medicine since its discovery in the late 19th century. However, the low availability of BBR in vivo prevents its full effect. In recent years, a large number of studies confirmed that BBR has a protective effect on the nervous system through various functions, yet the issue of the inability to systematically understand the protection of BBR on the nervous system remains a gap that needs to be addressed. Many existing literature introductions about berberine in neurodegenerative diseases, but the role of berberine in the nervous system goes far beyond these. Different from these literatures, this review is divided into three parts: preparation method, mechanism, and therapeutic effect. Various dosage forms of BBR and their preparation methods are added, in order to provide a reasonable choice of BBR, and help to solve the problem of low bioavailability in treatment. More importantly, we more comprehensively summarize the mechanism of BBR to protect the nervous system, in addition to the treatment of neurodegenerative diseases (anti-oxidative stress, anti-neuroinflammation, regulation of apoptosis), two extra mechanisms of berberine for the protection of the nervous system were also introduced: bidirectional regulation of autophagy and promote angiogenesis. Also, we have clarified the precise mechanism by which BBR has a therapeutic effect not only on neurodegenerative illnesses but also on multiple sclerosis, gliomas, epilepsy, and other neurological conditions. To sum up, we hope that these can evoke more efforts to comprehensively utilize of BBR nervous system, and to promote the application of BBR in nervous system protection.

Prepubertal Repeated Berberine Supplementation Enhances Cerebrocerebellar Functions by Modulating Neurochemical and Behavioural Changes in Wistar Rats

Antioxidant-rich supplementation plays an essential role in the function of mammals' central nervous system. However, no research has documented the effect of berberine (BER) supplementation on the cerebrocerebellar function of prepubertal rats. The present study was designed to investigate the impact of BER supplementation on neurochemical and behavioural changes in prepubertal male rats. Five groups (90 ± 5 g, n = 7 each) of experimental rats were orally treated with corn oil or different doses of BER (25, 50, 100, and 200 mg/kg bw) from the 28th at 68 post-natal days. On the 69 days of life, animals underwent behavioural assessment in the open field, hanging wire, and negative geotaxis tests. The result revealed that BER administration improved locomotive and motor behaviour by increasing distance travelled, line crossings, average speed, time mobile, and absolute turn angle in open field test and decrease in time to re-orient on an incline plane, a decrease in immobility time relative to the untreated control. Furthermore, BER supplementation increased (p < 0.05) antioxidant enzyme activities such as SOD, CAT, GPx, GSH, and TSH and prevented increases (p < 0.05) in oxidative and inflammatory levels as indicated by decreases in RONS, LPO, XO, carbonyl protein, NO, MPO, and TNF-α compared to the untreated control. BER-treated animals a lessened number of dark-stained Nissl cells compared to the untreated control rats. Our findings revealed that BER minimised neuronal degeneration and lesions, improved animal behaviour, and suppressed oxidative and inflammatory mediators, which may probably occur through its agonistic effect on PPAR-α, PPAR-δ, and PPAR-γ - essential proteins known to resolve inflammation and modulate redox signalling towards antioxidant function.

Bitter yet beneficial: The dual role of dietary alkaloids in managing diabetes and enhancing cognitive function

With the rising prevalence of diabetes and its association with cognitive impairment, interest in the use of dietary alkaloids and other natural products has grown significantly. Understanding how these compounds manage diabetic cognitive dysfunction (DCD) is crucial. This comprehensive review explores the etiology of DCD and the effects of alkaloids in foods and dietary supplements that have been investigated as DCD therapies. Data on how dietary alkaloids like berberine, trigonelline, caffeine, capsaicin, 1-deoxynojirimycin, nuciferine, neferine, aegeline, tetramethylpyrazine, piperine, and others regulate cognition in diabetic disorders were collected from PubMed, Research Gate, Web of Science, Science Direct, and other relevant databases. Dietary alkaloids could improve memory in behavioral models and modulate the mechanisms underlying the cognitive benefits of these compounds, including their effects on glucose metabolism, gut microbiota, vasculopathy, neuroinflammation, and oxidative stress. Evidence suggests that dietary alkaloids hold promise for improving cognition in diabetic patients and could open exciting avenues for future research in diabetes management.

Metabolomics analysis reveals characteristic metabolites in different levels of oxaliplatin-induced neurotoxicity

Oxaliplatin (L-OHP), a third-generation platinum-based anti-tumor drug, finds widespread application in the first-line treatment of metastatic colorectal cancer. Despite its efficacy, the drug's usage is curtailed by a litany of side effects, with L-OHP-induced peripheral neuropathy (OIPN) being the most debilitating. This condition can be classified into varying degrees of severity. Employing serum metabolomics, a high-sensitivity, high-throughput technique, holds promise as a method to identify biomarkers for clinical assessment and monitoring of OIPN patients across different severity levels. In our study, we analyzed serum metabolites in patients with different OIPN levels using ultra-performance liquid chromatography-high resolution mass spectrometry. By employing statistical analyses and pathway enrichment studies, we aimed to identify potential biomarkers and metabolic pathways. Our findings characterized the serum metabolic profiles of patients with varying OIPN levels. Notably, pathway analysis revealed a significant correlation with lipid metabolism, amino acid metabolism, and energy metabolism. Multivariate statistical analysis and receiver operator characteristic curve evaluation pointed to anhalamine and glycochenodeoxycholic acid as potential biomarkers for OIPN C and A, which suggest that serum metabolomics may serve as a potent tool for exploring the metabolic status of patients suffering from diverse diseases and for discovering novel biomarkers.

Paradigms and Success Stories of Natural Products in Drug Discovery Against Neurodegenerative Disorders (NDDs)

Neurodegenerative disorders (NDDs) are multifaceted complex disorders that have put a great health and economic burden around the globe nowadays. The multi-factorial nature of NDDs has presented a great challenge in drug discovery and continuous efforts are in progress in search of suitable therapeutic candidates. Nature has a great wealth of active principles in its lap that has cured the human population since ancient times. Natural products have revealed several benefits over conventional synthetic medications and scientists have shifted their vision towards exploring the therapeutic potentials of natural products in the past few years. The structural mimicking of natural compounds to endogenous ligands has presented them as a potential therapeutic candidate to prevent the development of NDDs. In the presented review, authors have summarized demographical facts about various NDDs including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and various types of sclerosis in the brain. The significant findings of new active principles of natural origin along with their therapeutic potentials on NDDs have been included. Also, a description of clinical trials and patents on natural products has been enlisted in this compilation. Although natural products have shown promising success in drug discovery against NDDs, still their use is associated with several ethical issues which need to be solved in the upcoming time.

Evaluation of berberine nanoparticles as a strategy to modulate acetylcholinesterase activity

Researchers have concentrated efforts in the search for natural-based reversible inhibitors for cholinesterase enzymes as they may play a key role in the treatment of degenerative diseases. Diverse plant alkaloids can inhibit the action of acetylcholinesterase and, among them, berberine is a promising bioactive. However, berberine has poor water solubility and low bioavailability, which makes it difficult to use in treatment. The solid dispersion technique can improve the water affinity of hydrophobic substances, but berberine solid dispersions have not been extensively studied. Safety testing is also essential to ensure that the berberine-loaded solid dispersions are safe for use. This study investigated the effectiveness of berberine-loaded solid dispersions (SD) as inhibitors of acetylcholinesterase enzyme (AChE). Docking simulation was used to investigate the influence of berberine on AChE, and in vitro assays were conducted to confirm the enzymatic kinetics of AChE in the presence of berberine. Berberine SD also showed improved cytotoxic effects on tumoral cells when dispersed in aqueous media. In vivo assays using Allium cepa were implemented, and no cytotoxicity/genotoxicity was found for the berberine solid dispersion. These results suggest that berberine SD could be a significant step towards safe nanostructures for use in the treatment of neurodegenerative diseases.

The potential role of RNA modification in skin diseases, as well as the recent advances in its detection methods and therapeutic agents

RNA modification is considered as an epigenetic modification that plays an indispensable role in biological processes such as gene expression and genome editing without altering nucleotide sequence, but the molecular mechanism of RNA modification has not been discussed systematically in the development of skin diseases. This article mainly presents the whole picture of theoretical achievements on the potential role of RNA modification in dermatology. Furthermore, this article summarizes the latest advances in clinical practice related with RNA modification, including its detection methods and drug development. Based on this comprehensive review, we aim to illustrate the current blind spots and future directions of RNA modification, which may provide new insights for researchers in this field.

Neuroprotective Properties of Berberine: Molecular Mechanisms and Clinical Implications

Berberine (BBR), an isoquinoline alkaloid natural product, is isolated primarily from Coptis chinensis and other Berberis plants. BBR possesses various bioactivities, including antioxidant, anti-inflammation, anticancer, immune-regulation, and antimicrobial activities. Growing scientific evidence underscores BBR's substantial neuroprotective potential, prompting increased interest and scrutiny. In this comprehensive review, we elucidate the neuroprotective attributes of BBR, delineate the underlying molecular mechanisms, and assess its clinical safety and efficacy. The multifaceted molecular mechanisms responsible for BBR's neuroprotection encompass the attenuation of oxidative stress, mitigation of inflammatory responses, inhibition of apoptotic pathways, facilitation of autophagic processes, and modulation of CYP450 enzyme activities, neurotransmitter levels, and gut microbiota composition. Furthermore, BBR engages numerous signaling pathways, including the PI3K/Akt, NF-κB, AMPK, CREB, Nrf2, and MAPK pathways, to confer its neuroprotective effects. This comprehensive review aims to provide a substantial knowledge base, stimulate broader scientific discourse, and facilitate advancements in the application of BBR for neuroprotection.

Berberine Alleviates the Damage, Oxidative Stress and Mitochondrial Dysfunction of PC12 Cells Induced by High Glucose by Activating the KEAP1/Nrf2/ARE Pathway

Diabetic encephalopathy (DE) is one of the major chronic complications of diabetes mellitus. This study aims to investigate the inhibitory effect of berberine (BBR) on the damage of PC12 cells induced by high glucose (HG). Differentiated PC12 cells were treated with different concentrations of glucose/BBR. The cell morphology, cell viability, lactate dehydrogenase (LDH) activity, apoptosis, oxidative stress (OS), mitochondrial structure, mitochondrial membrane potential (MMP), mitochondrial complex I-V activity, and adenosine triphosphate (ATP) levels were evaluated. The mRNA and protein levels of the Keap1/Nrf2/ARE pathway-related genes were assessed by RT-qPCR and Western blot. High-dose BBR and HG jointly treated-PC12 cells were treated with Nrf2-specific inhibitor ML385 to further verify whether Nrf2 was the target of BBR. The results showed that BBR inhibited cell damage, OS, and mitochondrial dysfunction induced by HG. The inhibitory effect of high BBR was more significant. The Keap1/Nrf2/ARE pathway was inhibited in PC12 cells induced by HG. BBR could activate the Keap1/Nrf2/ARE pathway, thus up-regulating the expression levels of antioxidant enzymes. ML385 antagonized the ameliorating effect of BBR on OS and mitochondrial dysfunction. The conclusion is that BBR can activate the Keap1/Nrf2/ARE pathway, upregulate the expression patterns of antioxidant enzymes, and reduce cell damage, OS, and mitochondrial dysfunction of PC12 cells induced by HG.

Berberine ameliorates iron levels and ferroptosis in the brain of 3 × Tg-AD mice

BACKGROUND

Berberine (BBR) is a natural alkaloid extracted from the herb Coptis chinensis. This compound has the ability to penetrate the blood-brain barrier (BBB) and exhibit neuroprotective value in the treatment of Alzheimer's disease (AD). AD is a neurodegenerative disease characterized by β-amyloid (Aβ) deposition, hyperphosphorylated tau and other characters. Iron accumulation and ferroptosis were also detected in AD brain, which can result in neuronal damage. However, it is still unclear whether BBR can suppress ferroptosis in AD and alleviate its underlying pathology.

PURPOSE

This study investigated whether BBR may affect ferroptosis and related signaling pathways in triple transgenic AD (3 × Tg-AD) mice.

METHODS

Four-month-old 3 × Tg-AD mice received oral administration of BBR at a dose of 50 mg/kg for 7.5 months. Cognitive function and anxiety levels in mice were assessed using the morris water maze test, open field test, and novel object recognition test. Western blot, immunohistochemistry, and ICP-MS were employed to assess the pathology of AD, brain iron metabolism, and ferroptosis signaling pathways. Transmission electron microscopy was used to detect mitochondrial changes. The synergistic effects of BBR combined with Nrf2 were investigated using molecular docking programs and surface plasmon resonance technology. Co-inmunoprecipitation assay was used to examine the effect of BBR on the binding ability of Nrf2 and Keap1.

RESULTS

The results indicated that chronic treatment of BBR mitigated cognitive disorders in 3 × Tg-AD model mice. Reductions in Aβ plaque, hyperphosphorylated tau protein, neuronal loss, and ferroptosis in the brains of 3 × Tg-AD mice suggested that BBR could alleviate brain injury. In addition, BBR treatment attenuated ferroptosis, as evidenced by decreased levels of iron, MDA, and ROS, while enhancing SOD, GSH, GPX4, and SLC7A11. Consistent with the in vivo assay, BBR inhibited RSL3-induced ferroptosis in N2a-sw cells. BBR increased the expression levels of GPX4, FPN1 and SLC7A11 by regulating Nrf2 transcription levels, thereby inhibiting ferroptosis. Molecular docking programs and surface plasmon resonance technology demonstrated the direct combination of BBR with Nrf2. Co-inmunoprecipitation analysis showed that BBR inhibited the interaction between Keap1 and Nrf2.

CONCLUSION

For the first time, these results showed that BBR could inhibit iron levels and ferroptosis in the brains of 3 × Tg-AD model mice and partially protect against RSL3-induced ferroptosis via the activation of Nrf2 signaling.

Phytobioactive compounds as therapeutic agents for human diseases: A review

Phytobioactive compounds are plant secondary metabolites and bioactive compounds abundantly present in medicinal plants and have remarkable therapeutic potential. Oxidative stress and antibiotic resistance are major causes of present-day ailments such as diabetes, atherosclerosis, cardiovascular disorders, cancer, and inflammation. The data for this review were collected from Google Scholar, PubMed, Directory of Open Access Journals (DOAJ), and Science Direct by using keywords: "Medicinal plants, Phytobioactive compounds, Polyphenols, Alkaloids, Carotenoids etc." Several studies have reported the pharmacological and therapeutic potential of the phytobioactives. Polyphenols, alkaloids, terpenes, and polysaccharides isolated from medicinal plants showed remarkable antioxidant, anticancer, cytotoxic, anti-inflammatory, cardioprotective, hepatoprotective, immunomodulatory, neuroprotective, and antidiabetic activities. This literature review was planned to provide comprehensive insight into the biopharmacological and therapeutic potential of phytobioactive compounds. The techniques used for the extraction and isolation of phytobioactive compounds, and bioassays required for their biological activities such as antioxidant, antimicrobial, anti-inflammatory, and cytotoxic activities, have been discussed. Characterization techniques for the structural elucidation of phytobioactive compounds such as HPLC, TLC, FTIR, GC-MS/MS, and NMR have also been discussed. This review concludes that phytobioactive compounds may be used as potential alternative to synthetic compounds as therapeutic agents for the treatment of various diseases.

Interaction of isoquinoline alkaloids with pyrimidine motif triplex DNA by mass spectrometry and spectroscopies reveals diverse mechanisms

Isoquinoline alkaloids represent an important class of molecules due to their broad range of pharmacology and clinical utility. Prospective development and use of these alkaloids as effective anticancer agents have elicited great interest. In this study, in order to reveal structure-activity relationship, we present the characterization of bioactive isoquinoline alkaloid-DNA triplex interactions, with particular emphasis on the sequence selectivity and preference of binding to the two types of DNA triplexes, by electrospray ionization mass spectrometry (ESI-MS) and various spectroscopic techniques. The six alkaloids, including coptisine, columbamine, epiberberine, berberrubine, jateorhizine, and fangchinoline, were selected to explore their interactions with the TC and TTT triplex DNA structures. Berberrubine, fangchinoline, coptisine, columbamine, and epiberberine have preference for TC rich DNA sequences compared to TTT rich DNA triplex based on affinity values in MS. The experimental results from different fragmentation modes in tandem MS, subtractive and hyperchromic effects in UV absorption spectra, fluorescence quenching and enhancement in fluorescence spectra, and strong conformational changes in circular dichroism (CD) hinted that the interaction between isoquinoline alkaloid-TC/TTT DNA had diverse mechanisms including at least two different binding modes: the electrostatic binding and the intercalation binding. Interestingly, columbamine, berberrubine, and fangchinoline can stabilize TTT triplex as inferred from optical thermal melting profiles, while it was not the case in TC triplex. These results provide new insights into binding of isoquinoline alkaloids to pyrimidine motif triplex DNA.

Berberine ameliorates depression-like behaviors in mice via inhibiting NLRP3 inflammasome-mediated neuroinflammation and preventing neuroplasticity disruption

OBJECTIVES

Neuroinflammation has been suggested that affects the processing of depression. There is renewed interest in berberine owing to its anti-inflammatory effects. Herein, we investigated whether berberine attenuate depressive-like behaviors via inhibiting NLRP3 inflammasome activation in mice model of depression.

METHODS

Adult male C57BL/6N mice were administrated corticosterone (CORT, 20 mg/kg/day) for 35 days. Two doses (100 mg/kg/day and 200 mg/kg/day) of berberine were orally administrated from day 7 until day 35. Behavioral tests were performed to measure the depression-like behaviors alterations. Differentially expressed gene analysis was performed for RNA-sequencing data in the prefrontal cortex. NLRP3 inflammasome was measured by quantitative reverse transcription polymerase chain reaction, western blotting, and immunofluorescence labeling. The neuroplasticity and synaptic function were measured by immunofluorescence labeling, Golgi-Cox staining, transmission electron microscope, and whole-cell patch-clamp recordings.

RESULTS

The results of behavioral tests demonstrated that berberine attenuated the depression-like behaviors induced by CORT. RNA-sequencing identified that NLRP3 was markedly upregulated after long-term CORT exposure. Berberine reversed the concentrations of peripheral and brain cytokines, NLRP3 inflammasome elicited by CORT in the prefrontal cortex and hippocampus were decreased by berberine. In addition, the lower frequency of neuronal excitation as well as the dendritic spine reduction were reversed by berberine treatment. Together, berberine increases hippocampal adult neurogenesis and synaptic plasticity induced by CORT.

CONCLUSION

The anti-depressants effects of berberine were accompanied by reduced the neuroinflammatory response via inhibiting the activation of NLRP3 inflammasome and rescued the neuronal deterioration via suppression of impairments in synaptic plasticity and neurogenesis.

Berberine inhibits RA-FLS cell proliferation and adhesion by regulating RAS/MAPK/FOXO/HIF-1 signal pathway in the treatment of rheumatoid arthritis

AIMS

Rheumatoid arthritis (RA) is a common chronic immune disease. Berberine, as its main active ingredient, was also contained in a variety of medicinal plants such as Berberaceae, Buttercup, and Rutaceae, which are widely used in digestive system diseases in traditional Chinese medicine with anti-inflammatory and antibacterial effects. The aims of this article were to explore the therapeutic effect and mechanism of berberine on rheumatoid arthritis.

METHODS

Cell Counting Kit-8 was used to evaluate the effect of berberine on the proliferation of RA fibroblast-like synoviocyte (RA-FLS) cells. The effect of berberine on matrix metalloproteinase (MMP)-1, MMP-3, receptor activator of nuclear factor kappa-Β ligand (RANKL), tumour necrosis factor alpha (TNF-α), and other factors was determined by enzyme-linked immunoassay (ELISA) kit. Transcriptome technology was used to screen related pathways and the potential targets after berberine treatment, which were verified by reverse transcription-polymerase chain reaction (RT-qPCR) and Western blot (WB) technology.

RESULTS

Berberine inhibited proliferation and adhesion of RA-FLS cells, and significantly reduced the expression of MMP-1, MMP-3, RANKL, and TNF-α. Transcriptional results suggested that berberine intervention mainly regulated forkhead box O (FOXO) signal pathway, prolactin signal pathway, neurotrophic factor signal pathway, and hypoxia-inducible factor 1 (HIF-1) signal pathway.

CONCLUSION

The effect of berberine on RA was related to the regulation of RAS/mitogen-activated protein kinase/FOXO/HIF-1 signal pathway in RA-FLS cells.Cite this article: Bone Joint Res 2023;12(2):91-102.

New insights into mechanisms of berberine in alleviating reproductive disorders of polycystic ovary syndrome: Anti-inflammatory properties

Polycystic ovary syndrome (PCOS) is a complex reproductive disorder that seriously harms female reproductive health and decreases quality of life. Although spontaneous or assisted ovulation occurs, women with PCOS suffer from poor-quality oocytes and embryos and lower fertilization and final pregnancy rates. Therefore, it is urgent to identify new pathological mechanisms and discover the underlying therapeutic targets for reproductive disorders associated with PCOS. Berberine, one of the famous traditional Chinese medicines, has been shown to improve ovulation and live birth rates in women with PCOS. The effects of berberine on insulin resistance and abnormal glucose and lipid metabolism for restoring the reproductive health of women with PCOS are well recognized and have been widely studied, but much less attention has been given to its anti-inflammatory properties. Chronic low-grade inflammation is the unifying feature of PCOS and may contribute to reproductive disorders in PCOS. Berberine can modulate the inflammatory state of the ovaries and uterus in PCOS. The anti-inflammatory properties of berberine may provide new insight into the mechanisms by which berberine alleviates reproductive disorders associated with PCOS. Here, we summarized the most recent insights into the anti-inflammatory properties of berberine in PCOS reproductive disorders to inspire researchers to pursue new study directions involving berberine.

Anti-Aging of the Nervous System and Related Neurodegenerative Diseases With Chinese Herbal Medicine

Human beings have always pursued a prolonged lifespan, while the aging of the nervous system is associated with a large variety of diseases. Pathological aging of the nervous system results in a series of neurodegenerative diseases and can cause disability and death in the elderly. Therefore, there is an urgent need for the prevention and treatment of nervous system aging. Chinese herbal medicines have a long history, featuring rich and safe ingredients, and have great potential for the development of anti-aging treatment. We searched the publications on PubMed with key words "anti-aging of the nervous system" and "Chinese herbal medicine" in recent 10 years, and found sixteen Chinese herbal medicines. Then by comparing their popularity of use as well as active components based on the research articles, five common Chinese herbal medicines namely Ginseng Radix, Lycii Fructus, Astragali Radix, Coptidis Rhizoma and Ginkgo Folium, were confirmed to be the most related to anti-nervous system aging and neural degenerative diseases. At the same time, the active ingredients, research models, action mechanisms and curative effects of these five common Chinese herbal medicines were reviewed. From the five common Chinese herbal medicines reviewed in this paper, many encouraging effects of Chinese herbal medicines on treating nervous system aging and related diseases were revealed and more potent herbs would be explored with the help of the proposed possible mechanisms.

Potential bioactive compounds and mechanisms of Fibraurea recisa Pierre for the treatment of Alzheimer's disease analyzed by network pharmacology and molecular docking prediction

Introduction

Heat-clearing and detoxifying Chinese medicines have been documented to have anti-Alzheimer's disease (AD) activities according to the accumulated clinical experience and pharmacological research results in recent decades. In this study, Fibraurea recisa Pierre (FRP), the classic type of Heat-clearing and detoxifying Chinese medicine, was selected as the object of research.

Methods

12 components with anti-AD activities were identified in FRP by a variety of methods, including silica gel column chromatography, multiple databases, and literature searches. Then, network pharmacology and molecular docking were adopted to systematically study the potential anti-AD mechanism of these compounds. Consequently, it was found that these 12 compounds could act on 235 anti-AD targets, of which AKT and other targets were the core targets. Meanwhile, among these 235 targets, 71 targets were identified to be significantly correlated with the pathology of amyloid beta (Aβ) and Tau.

Results and discussion

In view of the analysis results of the network of active ingredients and targets, it was observed that palmatine, berberine, and other alkaloids in FRP were the key active ingredients for the treatment of AD. Further, Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis revealed that the neuroactive ligand-receptor interaction pathway and PI3K-Akt signaling pathway were the most significant signaling pathways for FRP to play an anti-AD role. Findings in our study suggest that multiple primary active ingredients in FRP can play a multitarget anti-AD effect by regulating key physiological processes such as neurotransmitter transmission and anti-inflammation. Besides, key ingredients such as palmatine and berberine in FRP are expected to be excellent leading compounds of multitarget anti-AD drugs.

Phytochemical Characterization of Water Avens (Geum rivale L.) Extracts: Structure Assignment and Biological Activity of the Major Phenolic Constituents

Water avens (Geum rivale L.) is a common Rosaceae plant widely spread in Europe and North America. It is rich in biologically active natural products, some of which are promising as prospective pharmaceuticals. The extracts of water avens are well known for their triterpenoid metabolites and associated anti-inflammatory, antimicrobial and antioxidant activities. However, the polyphenolic profiles of G. rivale L. are still awaiting complete characterization. Accordingly, the contribution of its individual components to the antioxidant, antibacterial and neuroprotective activity of the extracts is still unknown. As this plant can be available on an industrial scale, a better knowledge of its properly-relevant constituents might give access to new highly-efficient pharmaceutical substances and functional products. Therefore, herein we comprehensively characterize the secondary metabolome of G. rivale by ESI-HR-MS, ESI-HR-MSⁿ and NMR spectroscopy with a special emphasis on the polyphenolic composition of its aerial parts. Furthermore, a multilateral evaluation of the antioxidant, neuroprotective and antibacterial properties of the aqueous and ethyl acetate fractions of the total aqueous alcoholic extract as well as individual isolated polyphenols was accomplished. Altogether four phenolic acid derivatives (trigalloyl hexose, caffeoyl-hexoside malate, ellagic acid and ellagic acid pentoside), six flavonoids (three quercetin derivatives, kaempferol and three its derivatives and two isorhamnetin derivatives) and four tannins (HHDP-hexoside, proantocyanidin dimer, pedunculagin I and galloyl-bis-HHDP-hexose) were identified in this plant for the first time. The obtained aqueous and ethyl acetate fractions of the total extract as well as the isolated individual compounds showed pronounced antioxidant activity. In addition, a pronounced antibacterial activity against several strains was proved for the studied fractions (for ethyl acetate fraction the highest activity against E. coli АТСС 25922 and S. aureus strains ATCC 27853 and SG-511 (MIC 15.6 μg/mL) was observed; for aqueous fraction-against Staphylococcus aureus SG-511 (MIC 31.2 μg/mL)). However, the anti-neurodegenerative (neuroprotective) properties could not be found with the employed methods. However, the antibacterial activity of the fractions could not be associated with any of the isolated individual major phenolics (excepting 3-O-methylellagic acid). Thus, the aerial parts of water avens represent a promising source of polyphenolic compounds with antioxidant activity and therefrom derived human health benefits, although the single constituents isolated so far lack a dominant selectively bioactive constituent in the bioassays performed.

Therapeutic roles of plants for 15 hypothesised causal bases of Alzheimer's disease

Alzheimer's disease (AD) is progressive and ultimately fatal, with current drugs failing to reverse and cure it. This study aimed to find plant species which may provide therapeutic bioactivities targeted to causal agents proposed to be driving AD. A novel toolkit methodology was employed, whereby clinical symptoms were translated into categories recognized in ethnomedicine. These categories were applied to find plant species with therapeutic effects, mined from ethnomedical surveys. Survey locations were mapped to assess how this data is at risk. Bioactivities were found of therapeutic relevance to 15 hypothesised causal bases for AD. 107 species with an ethnological report of memory improvement demonstrated therapeutic activity for all these 15 causal bases. The majority of the surveys were found to reside within biodiversity hotspots (centres of high biodiversity under threat), with loss of traditional knowledge the most common threat. Our findings suggest that the documented plants provide a large resource of AD therapeutic potential. In demonstrating bioactivities targeted to these causal bases, such plants may have the capacity to reduce or reverse AD, with promise as drug leads to target multiple AD hallmarks. However, there is a need to preserve ethnomedical knowledge, and the habitats on which this knowledge depends.

Berberine: A Promising Treatment for Neurodegenerative Diseases

Berberine, as a natural alkaloid compound, is characterized by a diversity of pharmacological effects. In recent years, many researches focused on the role of berberine in central nervous system diseases. Among them, the effect of berberine on neurodegenerative diseases has received widespread attention, for example Alzheimer's disease, Parkinson's disease, Huntington's disease, and so on. Recent evidence suggests that berberine inhibits the production of neuroinflammation, oxidative, and endoplasmic reticulum stress. These effects can further reduce neuron damage and apoptosis. Although the current research has made some progress, its specific mechanism still needs to be further explored. This review provides an overview of berberine in neurodegenerative diseases and its related mechanisms, and also provides new ideas for future research on berberine.

Berberine Protects against TNF-α-Induced Injury of Human Umbilical Vein Endothelial Cells via the AMPK/NF-κB/YY1 Signaling Pathway

Endothelial injury, characterized by an inflammatory response and increased permeability, is an initial stage of atherosclerosis (AS). Adenosine 5′-monophosphate (AMP), activated protein kinase (AMPK), and Nuclear Factor kappa B (NF-κB)/Yin Yang 1(YY1) signaling pathways play important roles in the process of endothelial injury. Berberine (BBR), a bioactive alkaloid isolated from several herbal substances, possesses multiple pharmacological effects, including anti-inflammatory, antimicrobial, antidiabetic, anticancer, and antioxidant activities. Previous studies showed a protective effect of berberine against endothelial injury. However, the underlying mechanism remains unclear. We explored the potential effect of BBR on TNF- (tumor necrosis factor-) α-induced injury of human umbilical endothelial cells (HUVECs) and studied its possible molecular mechanism. In the present study, HUVECs were divided into three groups. HUVEC viability was measured with Cell Counting Kit-8 assay. Extracellular lactic dehydrogenase (LDH) concentration was measured with LDH leakage assay. Endothelial microparticle (EMP) numbers were evaluated by flow cytometry analysis assay. The expression of proinflammatory cytokines was evaluated by Enzyme-Linked Immunosorbent Assay (ELISA). The mRNA expression of NF-κB and YY1 was detected by Real-Time PCR (RT-PCR). The protein expression of NF-κB, YY1, and AMPK was detected by immunofluorescence microscopy assay or western blot analysis. The results showed that LDH concentration, EMPs numbers, and the expression of proinflammatory cytokines (IL-6, IL-8, and IL-1β) increased in TNF-α-induced injured HUVECs, but ameliorated by BBR pretreatment. BBR pretreatment upregulated the expression of phosphorylated AMPK and downregulated the expressions of NF-κB and YY1 in injured HUVECs induced by TNF-α, which were offset by the AMPK inhibitor Compound C (CC). The results indicated that BBR protected against TNF-α-induced endothelial injury via the AMPK/NF-κB/YY1 signaling pathway.

Targeting Mitochondria by Plant Secondary Metabolites: A Promising Strategy in Combating Parkinson's Disease

Parkinson’s disease (PD) is one of the most prevalent and debilitating neurodegenerative conditions, and is currently on the rise. Several dysregulated pathways are behind the pathogenesis of PD; however, the critical targets remain unclear. Accordingly, there is an urgent need to reveal the key dysregulated pathways in PD. Prevailing reports have highlighted the importance of mitochondrial and cross-talked mediators in neurological disorders, genetic changes, and related complications of PD. Multiple pathophysiological mechanisms of PD, as well as the low efficacy and side effects of conventional neuroprotective therapies, drive the need for finding novel alternative agents. Recently, much attention has been paid to using plant secondary metabolites (e.g., flavonoids/phenolic compounds, alkaloids, and terpenoids) in the modulation of PD-associated manifestations by targeting mitochondria. In this line, plant secondary metabolites have shown promising potential for the simultaneous modulation of mitochondrial apoptosis and reactive oxygen species. This review aimed to address mitochondria and multiple dysregulated pathways in PD by plant-derived secondary metabolites.

Injectable antimicrobial hydrogels with antimicrobial peptide and sanguinarine controlled release ability for preventing bacterial infections

The emergence of antibiotic resistant bacteria represents a significant and common clinical problem worldwide as infections are becoming increasingly common. It is urgent to broaden the sources of biomaterials that can prevent both bacterial infection and antibiotic resistance. In this work, oxidized sodium alginate/aminated hyaluronic acid (OSA/AHA) hydrogel with various proportions was developed based on Schiff base reaction. Herein, polydopamine (PDA)-Bmkn2 nanoparticle and sanguinarine were incorporated into hydrogels to enhance antibacterial properties. The prepared PDA-Bmkn2 nanoparticles, with uniform particle size and good dispersion, could serve as a delivery system for Bmkn2. The prepared hydrogels showed appropriate swelling ratio, extremely good mechanical strengths and improved biodegradability. Meanwhile, the Bmkn2 and sanguinarine were released from the hydrogels in a sustainable manner. Furthermore, OSA/AHA/sanguinarine/PDA-Bmkn2 hydrogel (less than 10 μg/mL BmKn2 and 0.2 μg/mL sanguinarine) had excellent biocompatibility. Antibacterial experiments confirmed that OSA/AHA/sanguinarine/PDA-Bmkn2 hydrogel had effective antimicrobial activity on Escherichia coli and Staphylococcus aureus. Therefore, the prepared injectable hydrogels with good biocompatibility and excellent synergistic antibacterial activity promise great potential for preventing localized bacterial infections.

Berberine Suppresses Stemness and Tumorigenicity of Colorectal Cancer Stem-Like Cells by Inhibiting m6A Methylation

BACKGROUND

Cancer stem cells (CSCs) are able to survive after cancer therapies, resulting in tumor progression and recurrence, as is seen in colorectal cancer. Therapies targeting CSCs are regarded as novel and promising strategies for efficiently eradicating tumors. Berberine, an isoquinoline alkaloid extracted from the Chinese herbal medicine Coptis chinensis, was found to have antitumor activities against colorectal cancer, without knowing whether it exerts inhibitory effects on colorectal CSCs and the potential mechanisms.

METHODS

In this study, we examined the inhibitory roles of Berberine on CSCs derived from HCT116 and HT29 by culturing in serum-free medium. We also examined the effects of Berberine on m6A methylation via regulating fat mass and obesity-associated protein (FTO), by downregulating β-catenin.

RESULTS

We examined the effects of Berberine on the tumorigenicity, growth, and stemness of colorectal cancer stem-like cells. The regulatory effect of Berberine on N6-methyladenosine (m6A), an abundant mRNA modification, was also examined. Berberine treatment decreased cell proliferation by decreasing cyclin D1 and increasing p27 and p21 and subsequently induced cell cycle arrest at the G1/G0 phase. Berberine treatment also decreased colony formation and induced apoptosis. Berberine treatment transcriptionally increased FTO and thus decreased m6A methylation, which was reversed by both FTO knockdown and the addition of the FTO inhibitor FB23-2. Berberine induced FTO-related decreases in stemness in HCT116 and HT29 CSCs. Berberine treatment also increased chemosensitivity in CSCs and promoted chemotherapy agent-induced apoptosis. Moreover, we also found that Berberine treatment increased FTO by decreasing β-catenin, which is a negative regulator of FTO.

CONCLUSIONS

Our observation that Berberine effectively decreased m6A methylation by decreasing β-catenin and subsequently increased FTO suggests a role of Berberine in modulating stemness and malignant behaviors in colorectal CSCs.

Treatment of Parkinson's disease in Zebrafish model with a berberine derivative capable of crossing blood brain barrier, targeting mitochondria, and convenient for bioimaging experiments

Berberine is a famous alkaloid extracted from Berberis plants and has been widely used as medications and functional food additives. Recent studies reveal that berberine exhibits neuroprotective activity in animal models of Parkinson's disease (PD), the second most prevalent neurodegenerative disorders all over the world. However, the actual site of anti-PD action of berberine remains largely unknown. To this end, we employed a fluorescently labeled berberine derivative BBRP to investigate the subcellular localization and blood brain barrier (BBB) permeability in a cellular model of PD and zebrafish PD model. Biological investigations revealed that BBRP retained the neuroprotective activity of berberine against PD-like symptoms in PC12 cells and zebrafish, such as protecting 6-OHDA induced cell death, relieving MPTP induced PD-like behavior and increasing dopaminergic neuron loss in zebrafish. We also found that BBRP could readily penetrate BBB and function in the brain of zebrafish suffering from PD. Subcellular localization study indicated that BBRP could rapidly and specifically accumulate in mitochondria of PC12 cells when it exerted anti-PD effect. In addition, BBRP could suppress accumulation of Pink1 protein and inhibit the overexpression of LC3 protein in 6-OHDA damaged cells. All these results suggested that the potential site of action of berberine is mitochondria in the brain under the PD condition. Therefore, the findings described herein would be useful for further development of berberine as an anti-PD drug.

Inhibitory Role of Berberine, an Isoquinoline Alkaloid, on NLRP3 Inflammasome Activation for the Treatment of Inflammatory Diseases

The pyrin domain-containing multiprotein complex NLRP3 inflammasome, consisting of the NLRP3 protein, ASC adaptor, and procaspase-1, plays a vital role in the pathophysiology of several inflammatory disorders, including neurological and metabolic disorders, chronic inflammatory diseases, and cancer. Several phytochemicals act as promising anti-inflammatory agents and are usually regarded to have potential applications as complementary or alternative therapeutic agents against chronic inflammatory disorders. Various in vitro and in vivo studies have reported the anti-inflammatory role of berberine (BRB), an organic heteropentacyclic phytochemical and natural isoquinoline, in inhibiting NLRP3 inflammasome-dependent inflammation against many disorders. This review summarizes the mechanism and regulation of NLRP3 inflammasome activation and its involvement in inflammatory diseases, and discusses the current scientific evidence on the repressive role of BRB on NLRP3 inflammasome pathways along with the possible mechanism(s) and their potential in counteracting various inflammatory diseases.

Recent Progress on Biological Activity of Amaryllidaceae and Further Isoquinoline Alkaloids in Connection with Alzheimer's Disease

Alzheimer’s disease (AD) is a progressive age-related neurodegenerative disease recognized as the most common form of dementia among elderly people. Due to the fact that the exact pathogenesis of AD still remains to be fully elucidated, the treatment is only symptomatic and available drugs are not able to modify AD progression. Considering the increase in life expectancy worldwide, AD rates are predicted to increase enormously, and thus the search for new AD drugs is urgently needed. Due to their complex nitrogen-containing structures, alkaloids are considered to be promising candidates for use in the treatment of AD. Since the introduction of galanthamine as an antidementia drug in 2001, Amaryllidaceae alkaloids (AAs) and further isoquinoline alkaloids (IAs) have been one of the most studied groups of alkaloids. In the last few years, several compounds of new structure types have been isolated and evaluated for their biological activity connected with AD. The present review aims to comprehensively summarize recent progress on AAs and IAs since 2010 up to June 2021 as potential drugs for the treatment of AD.

Protective effects of berberine against MPTP-induced dopaminergic neuron injury through promoting autophagy in mice

Berberine, an isoquinoline alkaloid isolated from Coptis chinensis, has been widely studied for its efficacy in the treatment of neurodegenerative diseases. However, the detailed mechanisms are unknown. In this study, the effects of berberine on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mice model of Parkinson's disease were investigated. We showed that treatment with berberine significantly ameliorates the degeneration of dopaminergic neurons in substantia nigra compacta (SNc) and improves motor impairment in MPTP-treated mice. Berberine also significantly decreased the level of α-synuclein and enhanced the microtubule-associated protein light chain 3 (LC3-II)-associated autophagy in the SN of MPTP-treated mice. Furthermore, adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) was activated by berberine. Berberine's actions were abolished by pre-treatment with 3-methyladenine (an autophagy inhibitor) or compound c (an AMPK inhibitor) in the MPP+-treated SH-SY5Y cells. These results suggested that the protective effects of berberine on the toxicity of MPTP could be attributed to berberine-enhanced autophagy via the AMPK dependent pathway.

Neuroprotective Effect for Cerebral Ischemia by Natural Products: A Review

Natural products have a significant role in the prevention of disease and boosting of health in humans and animals. Stroke is a disease with high prevalence and incidence, the pathogenesis is a complex cascade reaction. In recent years, it’s reported that a vast number of natural products have demonstrated beneficial effects on stroke worldwide. Natural products have been discovered to modulate activities with multiple targets and signaling pathways to exert neuroprotection via direct or indirect effects on enzymes, such as kinases, regulatory receptors, and proteins. This review provides a comprehensive summary of the established pharmacological effects and multiple target mechanisms of natural products for cerebral ischemic injury in vitro and in vivo preclinical models, and their potential neuro-therapeutic applications. In addition, the biological activity of natural products is closely related to their structure, and the structure-activity relationship of most natural products in neuroprotection is lacking, which should be further explored in future. Overall, we stress on natural products for their role in neuroprotection, and this wide band of pharmacological or biological activities has made them suitable candidates for the treatment of stroke.

Berberine alleviates rotenone-induced cytotoxicity by antioxidation and activation of PI3K/Akt signaling pathway in SH-SY5Y cells

Berberine, an isoquinoline alkaloid isolated from traditional Chinese medicine, has been widely studied for its efficacy in the treatment of neurodegenerative diseases. However, berberine-mediated neuroprotection in the pathogenesis of Parkinson's disease is still uncertain. In this study, the effects of berberine on rotenone-induced neurotoxicity in SH-SY5Y cells were investigated. The results showed that berberine treatment significantly alleviated rotenone-induced decrease in the cell viability in SH-SY5Y cells. Further studies demonstrated that berberine suppressed the production of intracellular reactive oxygen species, restored the mitochondrial transmembrane potential, increased Bcl-2/Bax ratio, and decreased caspase-3 activation that induced by rotenone. Furthermore, berberine also restored the phosphorylation of Akt, which was downregulated by rotenone in SH-SY5Y cells. These results suggest that berberine protects rotenone-treated SH-SY5Y cells by antioxidation and activation of PI3K/Akt signaling pathway.

Ameliorating Ribosylation-Induced Amyloid-β Pathology by Berberine via Inhibiting mTOR/p70S6K Signaling

BACKGROUND

Berberine (BBR) plays a neuroprotective role in the pathogenesis of Alzheimer's disease (AD), inhibiting amyloid-β (Aβ) production and promoting Aβ clearance. Advanced glycation end products (AGEs) promote Aβ aggregation and tau hyperphosphorylation. The activation of mTOR signaling occurring at the early stage of AD has a prominent impact on the Aβ production. This work focused on whether BBR regulates the production and clearance of ribosylation-induced Aβ pathology via inhibiting mTOR signaling.

OBJECTIVE

To explore whether BBR ameliorates ribosylation-induced Aβ pathology in APP/PS1 mice.

METHODS

Western blot and immunofluorescence staining were used to detect the related proteins of the mammalian target of Rapamycin (mTOR) signaling pathway and autophagy, as well as the related kinases of Aβ generation and clearance. Tissue sections and Immunofluorescence staining were used to observe Aβ42 in APP/PS1 mice hippocampal. Morris water maze test was used to measure the spatial learning and memory of APP/PS1 mice.

RESULTS

BBR improves spatial learning and memory of APP/PS1 mice. BBR limits the activation of mTOR/p70S6K signaling pathway and enhances autophagy process. BBR reduces the activity of BACE1 and γ-secretase induced by D-ribose, and enhances Aβ-degrading enzymes and Neprilysin, and inhibits the expression of Aβ in APP/PS1 mice.

CONCLUSION

BBR ameliorates ribosylation-induced Aβ pathology via inhibiting mTOR/p70S6K signaling and improves spatial learning and memory of the APP/PS1 mice.

Polyphenolic molecules targeting STAT3 pathway for the treatment of cancer

Cancer is accounted as the second-highest cause of morbidity and mortality throughout the world. Numerous preclinical and clinical investigations have consistently highlighted the role of natural polyphenolic compounds against various cancers. A plethora of potential bioactive polyphenolic molecules, primarily flavonoids, phenolic acids, lignans and stilbenes, have been explored from the natural sources for their chemopreventive and chemoprotective activities. Moreover, combinations of these polyphenols with current chemotherapeutic agents have also demonstrated their strong role against both progression and resistance of malignancies. Signal transducer and activator of transcription 3 (STAT3) is a ubiquitously-expressed signaling molecule in almost all body cells. Thousands of literatures have revealed that STAT3 plays significant roles in promoting the cellular proliferation, differentiation, cell cycle progression, metastasis, angiogenesis and immunosuppression as well as chemoresistance through the regulation of its downstream target genes such as Bcl-2, Bcl-xL, cyclin D1, c-Myc and survivin. For its key role in cancer development, researchers considered STAT3 as a major target for cancer therapy that mainly focuses on abrogating the expression (activation or phosphorylation) of STAT3 in tumor cells both directly and indirectly. Polyphenolic molecules have explicated their protective actions in malignant cells via targeting STAT3 both in vitro and in vivo. In this article, we reviewed how polyphenolic compounds as well as their combinations with other chemotherapeutic drugs inhibit cancer cells by targeting STAT3 signaling pathway.

Integrated Analysis of m6A Methylome in Cisplatin-Induced Acute Kidney Injury and Berberine Alleviation in Mouse

Background

N6-methyladenosine (m6A) is the most abundant modification known in mRNAs. It participates in a variety of physiological and pathological processes, such as metabolism, inflammation, and apoptosis.

Aims

To explore the mechanism of m6A in cisplatin-induced acute kidney injury (AKI) and berberine alleviation in mouse.

Methods

This study investigated the N6-methyladenosine (m6A) methylome of kidneys from three mouse groups: C57 mice (controls), those with CI-AKI (injury group, IG), and those pretreated with berberine (treatment group, TG). Methylated RNA Immunoprecipitation Next Generation Sequencing (MeRIP-seq) and RNA-seq were performed to identify the differences between the injury group and the control group (IvC) and between the treatment group and the injury group (TvI). Western blotting was performed to identify the protein levels of candidate genes.

Results

In IvC, differentially methylated genes (DMGs) were enriched in metabolic processes and cell death. In TvI, DMGs were enriched in tissue development. Several genes involved in important pathways related to CI-AKI showed opposite methylation and expression trends in the IvC and TvI comparisons.

Conclusion

m6A plays an important role in cisplatin induced AKI and berberine may alleviate this process.

The Role of Natural Compounds and their Nanocarriers in the Treatment of CNS Inflammation

Neuroinflammation, which is involved in various inflammatory cascades in nervous tissues, can result in persistent and chronic apoptotic neuronal cell death and programmed cell death, triggering various degenerative disorders of the central nervous system (CNS). The neuroprotective effects of natural compounds against neuroinflammation are mainly mediated by their antioxidant, anti-inflammatory, and antiapoptotic properties that specifically promote or inhibit various molecular signal transduction pathways. However, natural compounds have several limitations, such as their pharmacokinetic properties and stability, which hinder their clinical development and use as medicines. This review discusses the molecular mechanisms of neuroinflammation and degenerative diseases of CNS. In addition, it emphasizes potential natural compounds and their promising nanocarriers for overcoming their limitations in the treatment of neuroinflammation. Moreover, recent promising CNS inflammation-targeted nanocarrier systems implementing lesion site-specific active targeting strategies for CNS inflammation are also discussed.

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.

Enhanced Clearance of Neurotoxic Misfolded Proteins by the Natural Compound Berberine and Its Derivatives

Background: Accumulation of misfolded proteins is a common hallmark of several neurodegenerative disorders (NDs) which results from a failure or an impairment of the protein quality control (PQC) system. The PQC system is composed by chaperones and the degradative systems (proteasome and autophagy). Mutant proteins that misfold are potentially neurotoxic, thus strategies aimed at preventing their aggregation or at enhancing their clearance are emerging as interesting therapeutic targets for NDs. Methods: We tested the natural alkaloid berberine (BBR) and some derivatives for their capability to enhance misfolded protein clearance in cell models of NDs, evaluating which degradative pathway mediates their action. Results: We found that both BBR and its semisynthetic derivatives promote degradation of mutant androgen receptor (ARpolyQ) causative of spinal and bulbar muscular atrophy, acting mainly via proteasome and preventing ARpolyQ aggregation. Overlapping effects were observed on other misfolded proteins causative of amyotrophic lateral sclerosis, frontotemporal-lobar degeneration or Huntington disease, but with selective and specific action against each different mutant protein. Conclusions: BBR and its analogues induce the clearance of misfolded proteins responsible for NDs, representing potential therapeutic tools to counteract these fatal disorders.