Alpinia oxyphylla Miq. and Its Active Compound P-Coumaric Acid Promote Brain-Derived Neurotrophic Factor Signaling for Inducing Hippocampal Neurogenesis and Improving Post-cerebral Ischemic Spatial Cognitive Functions

Beneficial Effects of Manilkara zapota-Derived Bioactive Compounds in the Epigenetic Program of Neurodevelopment

Gestational diet has a long-dated effect not only on the disease risk in offspring but also on the occurrence of future neurological diseases. During ontogeny, changes in the epigenetic state that shape morphological and functional differentiation of several brain areas can affect embryonic fetal development. Many epigenetic mechanisms such as DNA methylation and hydroxymethylation, histone modifications, chromatin remodeling, and non-coding RNAs control brain gene expression, both in the course of neurodevelopment and in adult brain cognitive functions. Epigenetic alterations have been linked to neuro-evolutionary disorders with intellectual disability, plasticity, and memory and synaptic learning disorders. Epigenetic processes act specifically, affecting different regions based on the accessibility of chromatin and cell-specific states, facilitating the establishment of lost balance. Recent insights have underscored the interplay between epigenetic enzymes active during embryonic development and the presence of bioactive compounds, such as vitamins and polyphenols. The fruit of Manilkara zapota contains a rich array of these bioactive compounds, which are renowned for their beneficial properties for health. In this review, we delve into the action of each bioactive micronutrient found in Manilkara zapota, elucidating their roles in those epigenetic mechanisms crucial for neuronal development and programming. Through a comprehensive understanding of these interactions, we aim to shed light on potential avenues for harnessing dietary interventions to promote optimal neurodevelopment and mitigate the risk of neurological disorders.

Niuhuang Qingxin Wan ameliorates depressive-like behaviors and improves hippocampal neurogenesis through modulating TrkB/ERK/CREB signaling pathway in chronic restraint stress or corticosterone challenge mice

Introduction: Chronic stress-associated hormonal imbalance impairs hippocampal neurogenesis, contributing to depressive and anxiety behaviors. Targeting neurogenesis is thus a promising antidepressant therapeutic strategy. Niuhuang Qingxin Wan (NHQXW) is an herbal formula for mental disorders in Traditional Chinese Medicine (TCM) practice, but its anti-depressant efficacies and mechanisms remain unverified. Methods: In the present study, we tested the hypothesis that NHQXW could ameliorate depressive-like behaviors and improve hippocampal neurogenesis by modulating the TrkB/ERK/CREB signaling pathway by utilizing two depression mouse models including a chronic restraint stress (CRS) mouse model and a chronic corticosterone (CORT) stress (CCS) induced mouse model. The depression-like mouse models were orally treated with NHQXW whereas fluoxetine was used as the positive control group. We evaluated the effects of NHQXW on depressive- and anxiety-like behaviors and determined the effects of NHQXW on inducing hippocampal neurogenesis. Results: NHQXW treatment significantly ameliorated depressive-like behaviors in those chronic stress mouse models. NHQXW significantly improved hippocampal neurogenesis in the CRS mice and CCS mice. The potential neurogenic mechanism of NHQXW was identified by regulating the expression levels of BDNF, TrkB, p-ERK (T202/T204), p-MEK1/2 (S217/221), and p-CREB (S133) in the hippocampus area of the CCS mice. NHQXW revealed its antidepressant and neurogenic effects that were similar to fluoxetine. Moreover, NHQXW treatment revealed long-term effects on preventing withdrawal-associated rebound symptoms in the CCS mice. Furthermore, in a bioactivity-guided quality control study, liquiritin was identified as one of the bioactive compounds of NHQXW with the bioactivities of neurogenesis-promoting effects. Discussion: Taken together, NHQXW could be a promising TCM formula to attenuate depressive- and anxiety-like behaviors against chronic stress and depression. The underlying anti-depressant mechanisms could be correlated with its neurogenic activities by stimulating the TrkB/ERK/CREB signaling pathway.

Sanpian decoction ameliorates cerebral ischemia-reperfusion injury by regulating SIRT1/ERK/HIF-1α pathway through in silico analysis and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

Cerebral ischemia-reperfusion injury (CIRI) is a complex pathophysiological process involving multiple factors, and becomes the footstone of rehabilitation after ischemic stroke. Sanpian decoction (SPD) has exhibited protective effects against CIRI, migraine, and other cerebral vascular diseases. However, the underlying mechanisms have not been completely elucidated.

AIM OF THE STUDY

This study sought to explore the potential mechanisms underlying the effect of SPD against CIRI.

MATERIALS AND METHODS

High-performance liquid chromatography (HPLC) and ultra-high-performance liquid chromatography (UPLC) were carried out to determine the chemical constituents of SPD. A network pharmacology approach combined with experimental verification was conducted to elucidate SPD's multi-component, multi-target, and multi-pathway mechanisms in CIRI occurrence. The pharmacodynamics of the decoction was evaluated by establishing the rat model of middle cerebral artery occlusion/reperfusion (MCAO/R). In vivo and in vitro experiments were carried out, and the therapeutic effects of SPD were performed using 2,3,5-triphenyltetrazolium chloride (TTC) staining, hematoxylin-eosin (HE) staining, and Nissl staining. We used terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and flow cytometry to evaluate cortex apoptosis. The quantification of mRNA and corresponding proteins were performed using real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blot respectively.

RESULTS

Our research showed that pretreatment with SPD improved neurological function and inhibited CIRI. Network pharmacology revealed that the hypoxia-inducible factor-1 (HIF-1) signaling pathway and mitogen-activated protein kinase (MAPK) signaling pathway-mediated apoptosis may be associated with CIRI. In vivo and in vitro experiments, we confirmed that SPD increased cerebral blood flow, improved neural function, and reduced neural apoptosis via up-regulating the expression of sirtuin 1 (SIRT1) and down-regulating phospho-extracellular regulated protein kinases (p-ERK)/ERK and HIF-1α levels in CIRI rats.

CONCLUSION

Taken together, the present study systematically revealed the potential targets and signaling pathways of SPD in the treatment of CIRI using in silico prediction and verified the therapeutic effects of SPD against CIRI via ameliorating apoptosis by regulating SIRT1/ERK/HIF-1α.

P-coumaric Acid: Advances in Pharmacological Research Based on Oxidative Stress

P-coumaric acid is an important phenolic compound that is mainly found in fruits, vegetables, grains, and fungi and is also abundant in Chinese herbal medicines. In this review, the pharmacological research progress of p-coumaric acid in recent years was reviewed, with emphasis on its role and mechanism in oxidative stress-related diseases, such as inflammation, cardiovascular diseases, diabetes, and nervous system diseases. Studies have shown that p-coumaric acid has a positive effect on the prevention and treatment of these diseases by inhibiting oxidative stress. In addition, p-coumaric acid also has anti-tumor, antibacterial, anti-aging skin and other pharmacological effects. This review will provide reference and inspiration for further research on the pharmacological effects of p-coumaric acid.

Protection of p-Coumaric acid against chronic stress-induced neurobehavioral deficits in mice via activating the PKA-CREB-BDNF pathway

There is a body of evidence to suggest that chronic stress modulates neurochemical homeostasis, alters neuronal structure, inhibits neurogenesis and contributes to development of mental disorders. Chronic stress-associated mental disorders present common symptoms of cognitive impairment and depression with complex disease mechanisms. P-coumaric acid (p-CA), a natural phenolic compound, is widely distributed in vegetables, cereals and fruits. p-CA exhibits a wide range of health-related effects, including anti-oxidative-stress, anti-mutagenesis, anti-inflammation and anti-cancer activities. The current study aims to evaluate the therapeutic potential of p-CA against stress-associated mental disorders. We assessed the effect of p-CA on cognitive deficits and depression-like behavior in mice exposed to chronic restraint stress (CRS); we used network pharmacology, biochemical and molecular biological approaches to elucidate the underlying molecular mechanisms. CRS exposure caused memory impairments and depression-like behavior in mice; p-CA administration attenuated these CRS-induced memory deficits and depression-like behavior. Network pharmacology analysis demonstrated that p-CA was possibly involved in multiple targets and a variety of signaling pathways. Among them, the protein kinase A (PKA) - cAMP-response element binding protein (CREB) - brain derived neurotrophic factor (BDNF) signaling pathway was predominant and further characterized. The levels of PKA, phosphorylated CREB (pCREB) and BDNF were significantly lowered in the hippocampus of CRS mice, suggesting disruption of the PKA-CREB-BDNF signaling pathway; p-CA treatment restored the signaling pathway. Furthermore, CRS upregulated expression of proinflammatory cytokines in hippocampus, while p-CA reversed the CRS-induced effects. Our findings suggest that p-CA will offer therapeutic benefit to patients with stress-associated mental disorders.

Mediterranean Shrub Species as a Source of Biomolecules against Neurodegenerative Diseases

Neurodegenerative diseases are associated with oxidative stress, due to an imbalance in the oxidation-reduction reactions at the cellular level. Various treatments are available to treat these diseases, although they often do not cure them and have many adverse effects. Therefore, it is necessary to find complementary and/or alternative drugs that replace current treatments with fewer side effects. It has been demonstrated that natural products derived from plants, specifically phenolic compounds, have a great capacity to suppress oxidative stress and neutralize free radicals thus, they may be used as alternative alternative pharmacological treatments for pathological conditions associated with an increase in oxidative stress. The plant species that dominate the Mediterranean ecosystems are characterized by having a wide variety of phenolic compound content. Therefore, these species might be important sources of neuroprotective biomolecules. To evaluate this potential, 24 typical plant species of the Mediterranean ecosystems were selected, identifying the most important compounds present in them. This set of plant species provides a total of 403 different compounds. Of these compounds, 35.7% are phenolic acids and 55.6% are flavonoids. The most relevant of these compounds are gallic, vanillic, caffeic, chlorogenic, p-coumaric, and ferulic acids, apigenin, kaempferol, myricitrin, quercetin, isoquercetin, quercetrin, rutin, catechin and epicatechin, which are widely distributed among the analyzed plant species (in over 10 species) and which have been involved in the literature in the prevention of different neurodegenerative pathologies. It is also important to mention that three of these plant species, Pistacea lentiscus, Lavandula stoechas and Thymus vulgaris, have most of the described compounds with protective properties against neurodegenerative diseases. The present work shows that the plant species that dominate the studied geographic area can provide an important source of phenolic compounds for the pharmacological and biotechnological industry to prepare extracts or isolated compounds for therapy against neurodegenerative diseases.

The Role of Progranulin (PGRN) in the Pathogenesis of Ischemic Stroke

Stroke is a life-threatening medical condition and is a leading cause of disability. Cerebral ischemia is characterized by a distinct inflammatory response starting with the production of various cytokines and other inflammation-related agents. Progranulin (PGRN), a multifunctional protein, is critical in diverse physiological reactions, such as cell proliferation, inflammation, wound healing, and nervous system development. A mature PGRN is anti-inflammatory, while granulin, its derivative, conversely induces pro-inflammatory cytokine expression. PGRN is significantly involved in the brain tissue and its damage, for example, improving mood and cognitive disorders caused by cerebral ischemia. It may also have protective effects against nerve and spinal cord injuries by inhibiting neuroinflammatory response and apoptosis or it may be related to the proliferation, accumulation, differentiation, and activation of microglia. PGRN is a neurotrophic factor in the central nervous system. It may increase post-stroke neurogenesis of the subventricular zone (SVZ), which is particularly important in improving long-term brain function following cerebral ischemia. The neurogenesis enhanced via PGRN in the ischemic brain SVZ may be attributed to the induction of PI3K/AKT and MAPK/ERK signaling routes. PGRN can also promote the proliferation of neural stem/progenitor cells through PI3K/AKT signaling pathway. PGRN increases hippocampal neurogenesis, reducing anxiety and impaired spatial learning post-cerebral ischemia. PGRN alleviates cerebral ischemia/reperfusion injury by reducing endoplasmic reticulum stress and suppressing the NF-κB signaling pathway. PGRN can be introduced as a potent neuroprotective agent capable of improving post-ischemia neuronal actions, mainly by reducing and elevating the inflammatory and anti-inflammatory cytokines. Expression, storage, cleavage, and function of progranulin (PGRN) in the pathogenesis of ischemic stroke.

p-Coumaric acid attenuates the effects of Aβ42 in vitro and in a Drosophila Alzheimer's disease model

Alzheimer's disease (AD) is the most common neurodegenerative condition in civilizations worldwide. The distinctive occurrence of amyloid-beta (Aβ) accumulation into insoluble fibrils is part of the disease pathophysiology with Aβ42 being the most toxic and aggressive Aβ species. The polyphenol, p-Coumaric acid (pCA), has been known to boost a number of therapeutic benefits. Here, pCA's potential to counteract the negative effects of Aβ42 was investigated. First, pCA was confirmed to reduce Aβ42 fibrillation using an in vitro activity assay. The compound was next examined on Aβ42-exposed PC12 neuronal cells and was found to significantly decrease Aβ42-induced cell mortality. pCA was then examined using an AD Drosophila melanogaster model. Feeding of pCA partially reversed the rough eye phenotype, significantly lengthened AD Drosophila's lifespan, and significantly enhanced the majority of the AD Drosophila's mobility in a sex-dependent manner. The findings of this study suggest that pCA may have therapeutic benefits for AD.

Lepidium meyenii Walp (Maca)-derived extracellular vesicles ameliorate depression by promoting 5-HT synthesis via the modulation of gut-brain axis

Depression is a common and debilitating condition for which effective treatments are needed. Lepidium meyenii Walp (Maca) is a plant with potential medicinal effects in treating depression. Recently, there has been growing interest in plant-derived extracellular vesicles (EVs) due to their low toxicity and ability to transport to human cells. Targeting the gut-brain axis, a novel strategy for depression management, may be achieved through the use of Maca-derived EVs (Maca-EVs). In this study, we successfully isolated Maca-EVs using gradient ultracentrifugation and characterized their shape, size, and markers (CD63 and TSG101). The in vivo imaging showed that the Dil-labeled Maca-EVs crossed the brain-blood barrier and accumulated in the brain. The behavioral tests revealed that Maca-EVs dramatically recovered the depression-like behaviors of unpredictable chronic mild stress (UCMS) mice. UCMS mice fecal were characterized by an elevated abundance of g_Enterococcus, g_Lactobacillus, and g_Escherichia_Shigella, which were significantly restored by administration of Maca-EVs. The effects of Maca-EVs on the altered microbial and fecal metabolites in UCMS mice were mapped to biotin, pyrimidine, and amino acid (tyrosine, alanine, aspartate, and glutamate) metabolisms, which were closely associated with the serotonin (5-HT) production. Maca-EVs were able to increase serum monoamine neurotransmitter levels in UCMS mice, with 5-HT showing the most significant changes. We further demonstrated that 5-HT improved the expression of brain-derived neurotrophic factor, a key regulator of neuronal plasticity, and its subsequent activation of TrkB/p-AKT signaling by regulating the GTP-Cdc42/ERK pathway. These findings suggest that Maca-EVs enhance 5-HT release, possibly by modulating the gut-brain axis, to improve depression behavior. Our study sheds light on a novel approach to depression treatment using plant-derived EVs.

Active components and molecular mechanisms of Sagacious Confucius' Pillow Elixir to treat cognitive impairment based on systems pharmacology

BACKGROUND

Sagacious Confucius' Pillow Elixir (SCPE) is a common clinical prescription to treat cognitive impairment (CI) in East Asia.

OBJECTIVE

To predict the active components of SCPE, identify the associated signaling pathway, and explore the molecular mechanism using systems pharmacology and an animal study.

METHODS

Systems pharmacology and Python programming language-based molecular docking were used to select and analyze the active components and targets. Senescence-accelerated prone 8 mice were used as a CI model. The molecular mechanism was evaluated using the water maze test, neuropathological observation, cerebrospinal fluid microdialysis, and Western blotting.

RESULTS

Thirty active components were revealed by screening relevant databases and performing topological analysis. Additionally, 376 differentially expressed genes for CI were identified. Pathway enrichment analysis, protein-protein interaction (PPI) network analysis and molecular docking indicated that SCPE played a crucial role in modulating the PI3K/Akt/mTOR signaling pathway, and 23 SCPE components interacted with it. In the CI model, SCPE improved cognitive function, increased the levels of the neurotransmitter 5-hydroxytryptamine (5-HT) and metabolite 5-hydroxyindole acetic acid (5-HIAA), ameliorated pathological damage and regulated the PI3K/AKT/mTOR signaling pathway. SCPE increased the LC3-II/LC3-I, p-PI3K p85/PI3K p85, p-AKT/AKT, and p-mTOR/mTOR protein expression ratios and inhibited P62 expression in the hippocampal tissue of the CI model.

CONCLUSION

Our study revealed that 23 active SCPE components improve CI by increasing the levels of the neurotransmitter 5-HT and metabolite 5-HIAA, suppressing pathological injury and regulating the PI3K/Akt/mTOR signaling pathway to improve cognitive function.

lncRNA TUSC7 sponges miR-10a-5p and inhibits BDNF/ERK pathway to suppress glioma cell proliferation and migration

OBJECTIVE

Gliomas as primary cerebral malignancies frequently occurring in adults have relatively high morbidity and mortality. The underlying role of long non-coding ribonucleic acids (lncRNAs) in malignancies has attracted much attention, among which tumor suppressor candidate 7 (TUSC7) is a novel tumor suppressor gene whose regulatory mechanism in human cerebral gliomas remains inconclusive.

METHODS AND RESULTS

In this study, bioinformatics analysis indicated that TUSC7 could specifically bind to microRNA (miR)-10a-5p, and according to quantitative polymerase chain reaction (q-PCR), miR-10a-5p was up-regulated in human glioma cells and negatively correlated with TUSC7 expression. Dual-luciferase reporter gene assay showed the ability of TUSC7 to bind to miR-10a-5p, and overexpression of TUSC7 notably inhibited miR-10a-5p expression, restrained human glioma cell proliferation and migration, and regulated cell cycle and cyclin expression via the brain-derived neurotrophic factor/extracellular signal-regulated kinase (BDNF/ERK) pathway. The inhibitory effect of TUSC7 on miR-10a-5p was also verified by designing miR-10a-5p overexpression and knockdown panels for wound healing, Transwell and Western blotting assays.

CONCLUSIONS

TUSC7 suppresses human glioma cell proliferation and migration by negatively modulating miR-10a-5p and inhibiting the BDNF/ERK pathway, thus acting as a tumor suppressor gene in human gliomas.

Neuroprotective Effects of P-Coumaric Acid on Haloperidol-Induced Catalepsy Through Ameliorating Oxidative Stress and Brain Dopamine Level

Objective

To evaluate the effect of p-coumaric acid (p-CA) on haloperidol-induced catalepsy in Swiss albino male mice.

Methods

To induce catalepsy, haloperidol (1 mg/kg i.p.) was administered for 21 consecutive days. p-CA (50, 75, and 100 mg/kg, PO) was administered 30 min before haloperidol injection for 21 consecutive days. For catalepsy, locomotor activity and motor coordination scores were recorded on the 17, 14, and 21 days of drug treatment, while the gait analysis score was recorded on day 21. After behavioral testing, animals were sacrificed, and various biochemical and histopathology tests of the brain were conducted. Dopamine, malondialdehyde, reduced glutathione (GSH), superoxide dismutase (SOD), and catalase activity were examined in the brain.

Results

Chronic administration of haloperidol significantly increased catalepsy in mice. It also produced hypolocomotion, motor coordination, and gait disturbance in mice. p-CA significantly inhibited haloperidol-induced catalepsy. Haloperidol significantly increased malondialdehyde levels in the brain. While dopamine levels in the brain dropped along with GSH, SOD, and catalase activity levels, which also had an impact on the histology of the brain. p-CA significantly reduced haloperidol-induced increases in brain oxidative stress, dopamine levels in the brain, and brain histology in mice.

Discussion

p-CA significantly reduced haloperidol-induced catalepsy, possibly through reducing oxidative stress and increasing brain dopamine levels. It can be a good candidate drug for extrapyramidal symptoms in Parkinson’s disease and adjuvant therapy with antipsychotic drugs.

What can traditional Chinese medicine do for adult neurogenesis?

Adult neurogenesis plays a crucial role in cognitive function and mood regulation, while aberrant adult neurogenesis contributes to various neurological and psychiatric diseases. With a better understanding of the significance of adult neurogenesis, the demand for improving adult neurogenesis is increasing. More and more research has shown that traditional Chinese medicine (TCM), including TCM prescriptions (TCMPs), Chinese herbal medicine, and bioactive components, has unique advantages in treating neurological and psychiatric diseases by regulating adult neurogenesis at various stages, including proliferation, differentiation, and maturation. In this review, we summarize the progress of TCM in improving adult neurogenesis and the key possible mechanisms by which TCM may benefit it. Finally, we suggest the possible strategies of TCM to improve adult neurogenesis in the treatment of neuropsychiatric disorders.

Protective Mechanisms of Nootropic Herb Shankhpushpi (Convolvulus pluricaulis) against Dementia: Network Pharmacology and Computational Approach

Convolvulus pluricaulis (CP), a Medhya Rasayana (nootropic) herb, is a major ingredient in Ayurvedic and Traditional Chinese formulae indicated for neurological conditions, namely, dementia, anxiety, depression, insanity, and epilepsy. Experimental evidence suggests various neuroactive potentials of CP such as memory-enhancing, neuroprotective, and antiepileptic. However, precise mechanisms underlying the neuropharmacological effects of CP remain unclear. The study, therefore, aimed at deciphering the molecular basis of neuroprotective effects of CP phytochemicals against the pathology of dementia disorders such as Alzheimer's (AD) and Parkinson's (PD) disease. The study exploited bioinformatics tools and resources, such as Cytoscape, DAVID (Database for annotation, visualization, and integrated discovery), NetworkAnalyst, and KEGG (Kyoto Encyclopedia of Genes and Genomes) database to investigate the interaction between CP compounds and molecular targets. An in silico analysis was also employed to screen druglike compounds and validate some selective interactions. ADME (absorption, distribution, metabolism, and excretion) analysis predicted a total of five druglike phytochemicals from CP constituents, namely, scopoletin, 4-hydroxycinnamic acid, kaempferol, quercetin, and ayapanin. In network analysis, these compounds were found to interact with some molecular targets such as prostaglandin G/H synthase 1 and 2 (PTGS1 and PTGS2), endothelial nitric oxide synthase (NOS3), insulin receptor (INSR), heme oxygenase 1 (HMOX1), acetylcholinesterase (ACHE), peroxisome proliferator-activated receptor-gamma (PPARG), and monoamine oxidase A and B (MAOA and MAOB) that are associated with neuronal growth, survival, and activity. Docking simulation further confirmed interaction patterns and binding affinity of selected CP compounds with those molecular targets. Notably, scopoletin showed the highest binding affinity with PTGS1, NOS3, PPARG, ACHE, MAOA, MAOB, and TRKB, quercetin with PTGS2, 4-hydroxycinnamic acid with INSR, and ayapanin with HMOX1. The findings indicate that scopoletin, kaempferol, quercetin, 4-hydroxycinnamic acid, and ayapanin are the main active constituents of CP which might account for its memory enhancement and neuroprotective effects and that target proteins such as PTGS1, PTGS2, NOS3, PPARG, ACHE, MAOA, MAOB, INSR, HMOX1, and TRKB could be druggable targets against dementia.

Repetitive Transcranial Magnetic Stimulation of the Brain After Ischemic Stroke: Mechanisms from Animal Models

Stroke is a common cerebrovascular disease with high morbidity, mortality, and disability worldwide. Post-stroke dysfunction is related to the death of neurons and impairment of synaptic structure, which results from cerebral ischemic damage. Currently, transcranial magnetic stimulation (TMS) techniques are available to provide clinically effective interventions and quantitative diagnostic and prognostic biomarkers. The development of TMS has been 40 years and a range of repetitive TMS (rTMS) protocols are now available to regulate neuronal plasticity in many neurological disorders, such as stroke, Parkinson disease, psychiatric disorders, Alzheimer disease, and so on. Basic studies in an animal model with ischemic stroke are significant for demonstrating potential mechanisms of neural restoration induced by rTMS. In this review, the mechanisms were summarized, involving synaptic plasticity, neural cell death, neurogenesis, immune response, and blood-brain barrier (BBB) disruption in vitro and vivo experiments with ischemic stroke models. Those findings can contribute to the understanding of how rTMS modulated function recovery and the exploration of novel therapeutic targets. The mechanisms of rTMS in treating ischemic stroke from animal models. rTMS can prompt synaptic plasticity by increasing NMDAR, AMPAR and BDNF expression; rTMS can inhibit pro-inflammatory cytokines TNF and facilitate the expression of anti-inflammatory cytokines IL-10 by shifting astrocytic phenotypes from A1 to A2, and shifting microglial phenotypes from M1 to M2; rTMS facilitated the release of angiogenesis-related factors TGFβ and VEGF in A2 astrocytes, which can contribute to vasculogenesis and angiogenesis; rTMS can suppress apoptosis by increasing Bcl-2 expression and inhibiting Bax, caspase-3 expression; rTMS can also suppress pyroptosis by decreasing caspase-1, IL-1β, ASC, GSDMD and NLRP1 expression. rTMS, repetitive transcranial magnetic stimulation; NMDAR, N-methyl-D-aspartic acid receptors; AMPAR: α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors; BDNF, brain-derived neurotrophic factor; VEGF, vascular endothelial growth factor; GSDMD: cleaved Caspase-1 cleaves Gasdermin D; CBF: cerebral blood flow.

P-Coumaric Acid Reverses Depression-Like Behavior and Memory Deficit Via Inhibiting AGE-RAGE-Mediated Neuroinflammation

Depression, a mood disorder, affects one in fifteen adults, has multiple risk factors and is associated with complicated underlying pathological mechanisms. P-coumaric acid (p-CA), a phenolic acid, is widely distributed in vegetables, fruits and mushrooms. P-CA has demonstrated a protective role against oxidative stress and inflammation in various diseases, including cardiovascular disease, diabetes and cancer. In the current study, we investigated the protection of p-CA against depression and memory impairment in a corticosterone (CORT)-induced chronic depressive mouse model. CORT administration resulted in depression-like behaviors and memory impairment. P-CA treatment alleviated CORT-induced depression-related behaviors and memory impairment. Network pharmacology predicted that p-CA had multiple targets and mediated various signaling pathways, of which inflammation-associated targets and signaling pathways are predominant. Western blotting showed CORT-induced activation of the advanced glycation end product (AGE)-receptor of AGE (RAGE) (AGE-RAGE) signaling and increased expression of the proinflammatory cytokines interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNFα) in the hippocampus, while p-CA treatment inactivated AGE-RAGE signaling and decreased the levels of IL-1β and TNFα, suggesting that protection against depression and memory impairment by p-CA is mediated by the inhibition of inflammation, mainly via the AGE-RAGE signaling pathway. Our data suggest that p-CA treatment will benefit patients with depression.

The Genus Alternanthera: Phytochemical and Ethnopharmacological Perspectives

Ethnopharmacological relevance: The genus Alternanthera (Amaranthaceae) comprises 139 species including 14 species used traditionally for the treatment of various ailments such as hypertension, pain, inflammation, diabetes, cancer, microbial and mental disorders.

Aim of the review: To search research gaps through critical assessment of pharmacological activities not performed to validate traditional claims of various species of Alternanthera. This review will aid natural product researchers in identifying Alternanthera species with therapeutic potential for future investigation.

Materials and methods: Scattered raw data on ethnopharmacological, morphological, phytochemical, pharmacological, toxicological, and clinical studies of various species of the genus Alternanthera have been compiled utilizing search engines like SciFinder, Google Scholar, PubMed, Science Direct, and Open J-Gate for 100 years up to April 2021.

Results: Few species of Alternanthera genus have been exhaustively investigated phytochemically, and about 129 chemical constituents related to different classes such as flavonoids, steroids, saponins, alkaloids, triterpenoids, glycosides, and phenolic compounds have been isolated from 9 species. Anticancer, antioxidant, antibacterial, CNS depressive, antidiabetic, analgesic, anti-inflammatory, and immunomodulator effects have been explored in the twelve species of the genus. A toxicity study has been conducted on 3 species and a clinical study on 2 species.

Conclusions: The available literature on pharmacological studies of Alternanthera species reveals that few species have been selected based on ethnobotanical surveys for scientific validation of their traditional claims. But most of these studies have been conducted on uncharacterized and non-standardized crude extracts. A roadmap of research needs to be developed for the isolation of new bioactive compounds from Alternanthera species, which can emerge out as clinically potential medicines.

Naringin Mediates Adult Hippocampal Neurogenesis for Antidepression via Activating CREB Signaling

The brain-derived neurotrophic factor/tropomyosin receptor kinase B/cAMP response element-binding protein (BDNF/TrkB/CREB) signaling pathway is a critical therapeutic target for inducing adult hippocampal neurogenesis and antidepressant therapy. In this study, we tested the hypothesis that naringin, a natural medicinal compound, could promote adult hippocampal neurogenesis and improve depression-like behaviors via regulating the BDNF/TrkB/CREB signaling pathway. We first investigated the effects of naringin on promoting adult hippocampal neurogenesis in both normal and chronic corticosterone (CORT)-induced depressive mice. Under physiological condition, naringin treatment enhanced the proliferation of neural stem/progenitor cells (NSPCs) and accelerated neuronal differentiation. In CORT-induced depression mouse model, naringin treatment promoted neuronal differentiation and maturation of NSPCs for hippocampal neurogenesis. Forced swim test, tail suspension test, and open field test confirmed the antidepressant and anxiolytic effects of naringin. Co-treatment of temozolomide (TMZ), a neurogenic inhibitor, abolished these antidepressant and anxiolytic effects. Meanwhile, naringin treatment increased phosphorylation of cAMP response element binding protein (CREB) but had no effect on the expression of brain-derived neurotrophic factor and phosphorylation of TrkB in the hippocampus of CORT-induced depressive mice. Co-treatment of CREB inhibitor 666-15, rather than TrkB inhibitor Cyc-B, abolished the neurogenesis-promoting and antidepressant effects of naringin. Taken together, naringin has antidepressant and anxiolytic effects, and the underlying mechanisms could be attributed to enhance hippocampal neurogenesis via activating CREB signaling.

Progranulin promotes hippocampal neurogenesis and alleviates anxiety-like behavior and cognitive impairment in adult mice subjected to cerebral ischemia

Aims

Cerebral ischemia can lead to anxiety and cognitive impairment due to the loss of hippocampal neurons. Facilitation of endogenous neurogenesis in the hippocampus is a potential therapeutic strategy for alleviating ischemia‐induced anxiety and cognitive impairment. Progranulin (PGRN), a secretory glycoprotein, has been reported to have a mitogentic effect on many cell types. However, it is not clear whether PGRN enhances hippocampal neurogenesis and promotes functional recovery.

Methods

Adult male C57BL/6 mice were subjected to permanent middle cerebral artery occlusion (pMCAO) and injected intracerebroventricularly with recombinant mouse PGRN 30 min after pMCAO. Anxiety‐like behavior was detected by the open field and the elevated plus maze tests, and spatial learning and memory abilities were evaluated by Morris water maze. Neurogenesis was examined by double labeling of BrdU and neural stem cells or neurons markers. For mechanism studies, the level of ERK1/2 and AKT phosphorylation were assessed by western blotting.

Results

Progranulin significantly alleviated anxiety‐like behavior and spatial learning and memory impairment induced by cerebral ischemia in mice. Consistent with the functional recovery, PGRN promoted neural stem cells (NSCs) proliferation and neuronal differentiation in the dentate gyrus (DG) after cerebral ischemia. PGRN upregulated the expression of phosphorylated ERK1/2 and Akt in the DG after cerebral ischemia.

Conclusions

Progranulin alleviates ischemia‐induced anxiety‐like behavior and spatial learning and memory impairment in mice, probably via stimulation of hippocampal neurogenesis mediated by activation of MAPK/ERK and PI3K/Akt pathways. PGRN might be a promising candidate for coping with ischemic stroke‐induced mood and cognitive impairment in clinic.

The effect of propofol on hypoxia- and TNF-α-mediated BDNF/TrkB pathway dysregulation in primary rat hippocampal neurons

AIMS

Hypoxia and inflammation may lead to BDNF/TrkB dysregulation and neurological disorders. Propofol is an anesthetic with neuroprotective properties. We wondered whether and how propofol affected BDNF/TrkB pathway in hippocampal neurons and astrocytes.

METHODS

Primary rat hippocampal neurons and astrocytes were cultured and exposed to propofol followed by hypoxia or TNF-α treatment. The expression of BDNF and the expression/truncation/phosphorylation of TrkB were measured. The underlying mechanisms were investigated.

RESULTS

Hypoxia and TNF-α reduced the expression of BDNF, which was reversed by pretreatment of 25 μM propofol in hippocampal neurons. Furthermore, hypoxia and TNF-α increased the phosphorylation of ERK and phosphorylation of CREB at Ser142, while reduced the phosphorylation of CREB at Ser133, which were all reversed by 25 μM propofol and 10 μM ERK inhibitor. In addition, hypoxia or TNF-α did not affect TrkB expression, truncation, or phosphorylation in hippocampal neurons and astrocytes. However, in hippocampal neurons, 50 μM propofol induced TrkB phosphorylation, which may be mediated by p35 expression and Cdk5 activation, as suggested by the data showing that blockade of p35 or Cdk5 expression mitigated propofol-induced TrkB phosphorylation.

CONCLUSIONS

Propofol modulated BDNF/TrkB pathway in hippocampal neurons via ERK/CREB and p35/Cdk5 under the condition of hypoxia or TNF-α exposure.

The Use of Bioactive Compounds in Hyperglycemia- and Amyloid Fibrils-Induced Toxicity in Type 2 Diabetes and Alzheimer’s Disease

It has become increasingly apparent that defective insulin signaling may increase the risk for developing Alzheimer’s disease (AD), influence neurodegeneration through promotion of amyloid formation or by increasing inflammatory responses to intraneuronal β-amyloid. Recent work has demonstrated that hyperglycemia is linked to cognitive decline, with elevated levels of glucose causing oxidative stress in vulnerable tissues such as the brain. The ability of β-amyloid peptide to form β-sheet-rich aggregates and induce apoptosis has made amyloid fibrils a leading target for the development of novel pharmacotherapies used in managing and treatment of neuropathological conditions such as AD-related cognitive decline. Additionally, deposits of β-sheets folded amylin, a glucose homeostasis regulator, are also present in diabetic patients. Thus, therapeutic compounds capable of reducing intracellular protein aggregation in models of neurodegenerative disorders may prove useful in ameliorating type 2 diabetes mellitus symptoms. Furthermore, both diabetes and neurodegenerative conditions, such as AD, are characterized by chronic inflammatory responses accompanied by the presence of dysregulated inflammatory biomarkers. This review presents current evidence describing the role of various small bioactive molecules known to ameliorate amyloidosis and subsequent effects in prevention and development of diabetes and AD. It also highlights the potential efficacy of peptide–drug conjugates capable of targeting intracellular targets.

Baoyuan Capsule promotes neurogenesis and neurological functional recovery through improving mitochondrial function and modulating PI3K/Akt signaling pathway

BACKGROUND

Bao Yuan Capsule (BYC) is a patented Chinese medicinal formula for health promotion but its application for ischemic stroke remains unknown. In this study, we proposed the hypothesis that BYC could promote neurogenesis and neurological functional recovery through promoting mitochondrial function and activating PI3K/Akt signaling pathway.

METHODS

We firstly performed chemical identification studies by using QIT-TOF-MS technology. Then, we investigated the effects of BYC (1 g/kg, 2 g/kg, 4 g/kg per day) on improving the recovery of the neurological functions in transient middle cerebral artery occlusion (MCAO) ischemic mice.

RESULTS

We tentatively characterized 36 compounds from the BYC extractions. At dosage of 4 g/kg, BYC effectively improved locomotor ability, attenuated anxiety-like behaviors, and enhanced the exploring behaviors, learning and memory capability in the transient MCAO ischemic mice. BYC treatment promoted neural stem cell differentiations in the subventricular zone (SVZ) and subgranular zone (SGZ) of the MCAO mice. BYC also up-regulated the expression of Aconitase 2 (ACO2), Succinate dehydrogenase complex, subunit A (SDHA), phosphorylation of AMP-activated protein kinase (p-AMPK), protein kinase B (p-Akt) and glycogen synthase kinase 3β (p-GSK3β) in the hippocampus of the MCAO mice. BYC (200 µg/ml) significantly improved the mitochondrial functions in cultured mouse multipotent neural stem like C17.2 cells. BYC treatment also promoted neuronal differentiations in the C17.2 cells under oxygen-glucose deprivation (OGD) condition. The neurogenetic effects were abolished by co-treatments of ATP synthesis inhibitor oligomycin and PI3K/Akt inhibitor wortmannin. Moreover, Akt phosphorylation was dramatically reduced by oligomycin.

CONCLUSION

BYC could promote neurogenesis and neurological functional recovery in post ischemic brains by regulating the mitochondrial functions and Akt signaling pathway.

Brain-derived Neurotrophic Factor and Its Applications through Nanosystem Delivery

Brain-derived neurotrophic factor (BDNF) is a protein that performs a neurotrophic function. BDNF and its receptors are widely expressed in the nervous system and can promote the growth of neurons and the formation of neuronal synapses in the brain. Studies have shown that a lack of BDNF can lead to impairment of memory and cognitive functions, indicating that BDNF plays an important role in mental illness and neurodegenerative diseases. The combination of stem cells and BDNF-releasing nanomaterials holds great promise in regenerative medicine, especially in the treatment of neurological diseases. For example, Alzheimer's disease, depression, Parkinson's disease, spinal cord injury, etc. The combination of stem cell/pharmacologically active carrier and BDNF-nano/hydrogel provided a useful new type of local delivery tool for the treatment of the nervous system and other diseases. It can not only provide BDNF but also stem cells. These studies will provide a scientific basis for the development and application of BDNF in the future.