Puerarin attenuates neuronal degeneration and blocks oxidative stress to elicit a neuroprotective effect on substantia nigra injury in 6-OHDA-lesioned rats

Neuroimmune modulators derived from natural products: Mechanisms and potential therapies

Neuroimmunology is a multidisciplinary field that investigates the interactions between the nervous and immune systems. Neuroimmune interactions persist throughout the entire lifespan, and their dysregulation can lead to the onset and development of multiple diseases. Despite significant progress over the past decades in elucidating the interaction between neuroscience and immunology, the exact mechanism underlying neuroimmune crosstalk has not yet been fully elucidated. In recent years, natural products have emerged as a promising avenue for the therapeutic implications of neuroimmune diseases. Naturally derived anti-neuroimmune disease agents, such as polyphenols, flavonoids, alkaloids, and saponins, have been extensively studied for their potential neuroimmune modulatory effects. This comprehensive review delves into the specific molecular mechanisms of bidirectional neuro-immune interactions, with particular emphasis on the role of neuro-immune units. The review synthesizes a substantial body of evidence from in vitro and in vivo experiments as well as clinical studies, highlighting the therapeutic potential of various natural products in intervening in neuroimmune disorders.

Investigating the Potential Therapeutic Mechanisms of Puerarin in Neurological Diseases

Plants and their derived phytochemicals have a long history of treating a wide range of illnesses for several decades. They are believed to be the origin of a diverse array of medicinal compounds. One of the compounds found in kudzu root is puerarin, a isoflavone glycoside commonly used as an alternative medicine to treat various diseases. From a biological perspective, puerarin can be described as a white needle crystal with the chemical name of 7-hydroxy-3-(4-hydroxyphenyl)-1-benzopyran-4-one-8-D-glucopyranoside. Besides, puerarin is sparingly soluble in water and produces no color or light yellow solution. Multiple experimental and clinical studies have confirmed the significant therapeutic effects of puerarin. These effects span a wide range of pharmacological effects, including neuroprotection, hepatoprotection, cardioprotection, immunomodulation, anticancer properties, anti-diabetic properties, anti-osteoporosis properties, and more. Puerarin achieves these effects by interacting with various cellular and molecular pathways, such as MAPK, AMPK, NF-κB, mTOR, β-catenin, and PKB/Akt, as well as different receptors, enzymes, and growth factors. The current review highlights the molecular mechanism of puerarin as a neuroprotective agent in the treatment of various neurodegenerative and neurological diseases. Extensive cellular, animal, and clinical research has provided valuable insights into its effectiveness in conditions such as Alzheimer's disease, Parkinson's disease, epilepsy, cerebral stroke, depression, and more.

Puerarin: a potential natural neuroprotective agent for neurological disorders

Puerarin is an isoflavone compound derived from Pueraria lobata in traditional Chinese medicine. Accumulating evidence has indicated that puerarin demonstrates multiple pharmacological effects and exhibits treatment potential for various neurological disorders. Based on the latest research progress on puerarin as a neuroprotective agent, its pharmacological activity, molecular mechanism, and therapeutic application were systematically reviewed with emphasis on pre-clinical studies. The related information was extracted and compiled from major scientific databases, including PubMed, ScienceDirect, SpringerLink, and Chinese National Knowledge Infrastructure, using 'Puerarin', 'Neuroprotection', 'Apoptosis', 'Autophagy', 'Antioxidant', 'Mitochondria', 'Anti-inflammation' as keywords. This review complied with The Preferred Reporting Items for Systematic Reviews criteria. Forty-three articles met established inclusion and exclusion criteria. Puerarin has shown neuroprotective effects against a variety of neurological disorders, including ischemic cerebrovascular disease, subarachnoid hemorrhage, epilepsy, cognitive disorders, traumatic brain injury, Parkinson's disease, Alzheimer's disease, anxiety, depression, diabetic neuropathy, and neuroblastoma/glioblastoma. Puerarin demonstrates anti-apoptosis, proinflammatory mediator inhibitory, autophagy regulatory, anti-oxidative stress, mitochondria protection, Ca²⁺ influx inhibitory, and anti-neurodegenerative activities. Puerarin exerts noticeable neuroprotective effects on various models of neurological disorders in vivo (animal). This review will contribute to the development of puerarin as a novel clinical drug candidate for the treatment of neurological disorders. However, well-designed, high-quality, large-scale, multicenter randomized clinical studies are needed to determine the safety and clinical utility of puerarin in patients with neurological disorders.

Therapeutic potential of puerarin against cerebral diseases: From bench to bedside

The incidence of cerebral diseases is rapidly increasing worldwide, and they have become an important challenge for modern medicine. Most of the available chemical drugs used in the treatment of cerebral diseases are highly toxic and single-targeted. Therefore, novel drugs from natural resources have attracted much attention for their potential to manage cerebral diseases. Puerarin is a natural isoflavone isolated from the roots of Pueraria species such as P. lobata (Willd) Ohwi, P. thomsonii, and P. mirifica. Several authors have reported the beneficial effects of puerarin in cerebral ischemic disease, intracerebral hemorrhage, vascular dementia, Alzheimer's disease, Parkinson's disease, depression, anxiety, and traumatic brain injury. This review summarizes the brain pharmacokinetics, brain drug delivery system, clinical use (in cerebral diseases), toxicity, and the adverse clinical reactions of puerarin. We have systematically presented the pharmacological actions and the molecular mechanisms of puerarin in various cerebral diseases to provide a direction for future research on the therapeutic use of puerarin in cerebral diseases.

Pharmacological Modulation of Nrf2/HO-1 Signaling Pathway as a Therapeutic Target of Parkinson's Disease

Parkinson's disease (PD) is a complex neurodegenerative disorder featuring both motor and nonmotor symptoms associated with a progressive loss of dopaminergic neurons in the substantia nigra pars compacta. Oxidative stress (OS) has been implicated in the pathogenesis of PD. Genetic and environmental factors can produce OS, which has been implicated as a core contributor to the initiation and progression of PD through the degeneration of dopaminergic neurons. The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) orchestrates activation of multiple protective genes, including heme oxygenase-1 (HO-1), which protects cells from OS. Nrf2 has also been shown to exert anti-inflammatory effects and modulate both mitochondrial function and biogenesis. Recently, a series of studies have reported that different bioactive compounds were shown to be able to activate Nrf2/antioxidant response element (ARE) and can ameliorate PD-associated neurotoxin, both in animal models and in tissue culture. In this review, we briefly overview the sources of OS and the association between OS and the pathogenesis of PD. Then, we provided a concise overview of Nrf2/ARE pathway and delineated the role played by activation of Nrf2/HO-1 in PD. At last, we expand our discussion to the neuroprotective effects of pharmacological modulation of Nrf2/HO-1 by bioactive compounds and the potential application of Nrf2 activators for the treatment of PD. This review suggests that pharmacological modulation of Nrf2/HO-1 signaling pathway by bioactive compounds is a therapeutic target of PD.

Anti-coronavirus disease 2019 (COVID-19) targets and mechanisms of puerarin

The present study aimed to uncover the pharmacological function and underlying mechanism of puerarin as a potential treatment for COVID‐19, using an in silico methodology, including network pharmacology and molecular docking. The pivotal targets of puerarin to treat COVID‐19 were identified and included the epidermal growth factor receptor (EGFR), tumour necrosis factor (TNF), tumour protein p53 (TP53), caspase 3 (CASP3), RELA proto‐oncogene (RELA), Fos proto‐oncogene (FOS), caspase 8 (CASP8), prostaglandin‐endoperoxide synthase 2 (PTGS2), interleukin 2 (IL2), protein kinase CB (PRKCB), B cell lymphoma/leukaemia gene‐2 (BCL2), protein kinase CA (PRKCA), nitric oxide synthase 3 (NOS3) and peroxisome proliferator–activated receptor gamma (PPARG). Functionally, the anti–COVID‐19 action of puerarin was associated with the suppression of oxidative stress and inflammatory cascades, and cell apoptosis. The signalling pathways of puerarin to treat COVID‐19 included modulation of the pathways of apoptosis, IL‐17 signalling, mitogen‐activated protein kinase (MAPK) signalling and TNF signalling. Molecular docking data illustrated the binding capacity of puerarin with COVID‐19 and the effective anti–COVID‐19 activity of puerarin. Taken together, our current network pharmacology–based findings revealed the pharmacological role of puerarin in the treatment of COVID‐19. Furthermore, the bioinformatic findings elucidated that some of these pivotal targets might serve as potential molecular markers for detecting COVID‐19.

Parkinson's disease a futile entangle of Mankind's credence on an herbal remedy: A review

Parkinson's disease (PD) is a disease of the human nervous system with an onset, in the sixth and seventh decades of the human life. Chiefly perceived as progressive degeneration of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) with the ensued loss of dopamine in the striatum and the presence of Lewy bodies, consisting of α-synuclein agglomeration. In which the neuronal bridge between substantia nigra and striatum plays an advent role in the motor system. Dilapidation of these neurons results in dopamine depletion which in-turn makes hay to PD. Eventually, the etiology and pathogenesis of PD were still on a hike of dilemma. Traditional Chinese medicine (TCM), including Chinese herbal remedies, acupuncture, and manipulative therapies, is commonly used as an adjunctive therapy in different diseases, particularly neurological diseases, in Asian countries. Additionally, TCM might improve the prognoses and the quality of life of patients with PD because it induces less adverse drug reactions. The present review describes research on the various neuroprotective components and herbal extracts from herbal medicines in the context of addressing the effects of PD.

An Overview of Crucial Dietary Substances and Their Modes of Action for Prevention of Neurodegenerative Diseases

Neurodegenerative diseases, namely Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis, Huntington's disease, and multiple sclerosis are becoming one of the main health concerns due to the increasing aging of the world's population. These diseases often share the same biological mechanisms, including neuroinflammation, oxidative stress, and/or protein fibrillation. Recently, there have been many studies published pointing out the possibilities to reduce and postpone the clinical manifestation of these deadly diseases through lifelong consumption of some crucial dietary substances, among which phytochemicals (e.g., polyphenols) and endogenous substances (e.g., acetyl-L-carnitine, coenzyme Q10, n-3 poysaturated fatty acids) showed the most promising results. Another important issue that has been pointed out recently is the availability of these substances to the central nervous system, where they have to be present in high enough concentrations in order to exhibit their neuroprotective properties. As so, such the aim of this review is to summarize the recent findings regarding neuroprotective substances, their mechanisms of action, as well as to point out therapeutic considerations, including their bioavailability and safety for humans.

Prior exercise protects against oxidative stress and motor deficit in a rat model of Parkinson's disease

This study investigated if a prior long-term physical exercise protocol protects the substantia nigra and the striatum against oxidative stress and motor deficits in a Parkinson Disease model induced by 6-hydroxydopamine. Three animal treatment groups were included in the study: sham; 6-hydroxydopamine and 6-hydroxydopamine/exercise. Previously to the intrastriatal lesion by 6-hydroxydopamine, rats in the exercise groups performed a swimming program for 18 weeks. The rats were submitted to behavioral tests before and after intrastriatal 6-hydroxydopamine injection. The oxidative stress was analyzed by Thiobarbituric Acid Reactive Substances and Glutathione reductase activity methods. The exercise decreased lipid peroxidation and increased glutathione reductase activity in the substantia nigra. In contrast, in the striatum, exercise increased lipid peroxidation and decreased glutathione reductase activity. Exercise increased contralateral rotations and reduces immobility levels at 14 days post lesion. The exercise prior to 6-OHDA lesion had protective action only in substantia nigra against oxidative stress.

In Vitro and In Vivo Neuroprotective Effects of Stellettin B Through Anti-Apoptosis and the Nrf2/HO-1 Pathway

Pharmaceutical agents for halting the progression of Parkinson’s disease (PD) are lacking. The current available medications only relieve clinical symptoms and may cause severe side effects. Therefore, there is an urgent need for novel drug candidates for PD. In this study, we demonstrated the neuroprotective activity of stellettin B (SB), a compound isolated from marine sponges. We showed that SB could significantly protect SH-SY5Y cells against 6-OHDA-induced cellular damage by inhibiting cell apoptosis and oxidative stress through PI3K/Akt, MAPK, caspase cascade modulation and Nrf2/HO-1 cascade modulation, respectively. In addition, an in vivo study showed that SB reversed 6-OHDA-induced a locomotor deficit in a zebrafish model of PD. The potential for developing SB as a candidate drug for PD treatment is discussed.

Supplementation of lycopene attenuates lipopolysaccharide-induced amyloidogenesis and cognitive impairments via mediating neuroinflammation and oxidative stress

Neuroinflammation is documented to be the major culprit of Alzheimer's disease. Lycopene (LYC), a fat soluble carotenoid, exhibits neuroprotective function in several neurodegenerative disorders. However, the effects of LYC to countering systemic inflammation-induced amyloidogenesis and memory deficiency remain to be elucidated. In current study, 3-month-old male C57BL/6J mice were treated with 0.03% LYC (w/w, mixed into normal chow) for 5 weeks. The mice were then treated by intraperitoneal injection of LPS (0.25mg/kg) for 9 days. It was found that LYC inhibited LPS-induced memory loss by behavior tests including Y-maze test and Morris water test. Meanwhile, LYC prevented LPS-induced accumulation of Aβ, levels of amyloid precursor protein (APP), and suppressed neuronal β-secretase BACE1 and elevated the expressions of α-secretase ADAM10. Furthermore, LYC down-regulated the expression of IBA-1 (a marker of microglia activation), reduced the levels of inflammatory mediators and inhibited oxidative stress in LPS-treated mice. Moreover, LYC suppressed the phosphorylation of MAPKs, NFκB, and activated Nrf2 signaling pathways in LPS-treated BV2 microglial cells. Therefore, our study indicated that LYC could ameliorate LPS-induced neuroinflammation, oxidative stress, amyloidogenesis and cognitive impairments possibly through mediating MAPKs, NFκB and Nrf2 signaling pathways, indicating that LYC might be a nutritional preventive strategy in neuroinflammation-related diseases such as AD.

Comparative Therapeutic Effects of Plant-Extract Synthesized and Traditionally Synthesized Gold Nanoparticles on Alcohol-Induced Inflammatory Activity in SH-SY5Y Cells In Vitro

The present study describes potential beneficial and adverse effects of plant-extract synthesized gold nanoparticles (AuNPs) on ethanol toxicity in SH-SY5Y cells. Although kudzu root extract (K), edible-gum extract (G), alone or in combination (KG), reduced Au³⁺ into AuNPs, the extract’s composition and the reaction temperature determined their size (AuNP_KG(90<50<37) << AuNP_K(90,50<37) < AuNP_G(90<50); the subscript KG, K, or G is extract identification and numerical vales are reaction temperature in Celsius) and biological properties (AuNP_KG(90,50>37) << AuNP_K(90,50>37) < AuNP_G(90,50)). The surface of each AuNP contained the extract’s active ingredients, that were analyzed and confirmed using laser desorption ionization (LDI)) and low-matrix laser desorption-ionization (_LMALDI). AuNP_KG-50 was (i) least toxic to SH-SY5Y cells, but most effective in suppressing the adverse effects of ethanol on SH-SY5Y cells, and (ii) more effective than a combination of free kudzu and gum extracts. The beneficial and adverse effects of AuNPs may have been modified by the formation of proteins corona. This study provides a proof of concept for possible application of plant-extract synthesized AuNPs in mitigating ethanol toxicity.

High Gpx1 expression predicts poor survival in laryngeal squamous cell carcinoma

OBJECTIVE

Several studies have demonstrated that abnormal glutathione peroxidases 1 (Gpx1) expression can influence the biological behavior of malignant cells. However, the roles of Gpx1 in laryngeal squamous cell carcinoma (LSCC) remain unknown. The purpose of this study is to analyze the Gpx1 expression and prognostic significance in LSCC patients.

METHODS

Gpx1 mRNA levels in laryngeal tissues were determined by qRT-PCR. Meanwhile, We examined the expression levels of Gpx1 protein in 140 primary tumor tissues and 28 cases of normal tissues by immunohistochemistry (IHC) analysis on tissue microarrays (TMA).

RESULTS

Our results revealed that the frequency of high Gpx1 was significantly higher in cancer tissue compared to normal surgical margins; Gpx1 expression correlated with clinical features and overall survival (OS). Gpx1 overexpression was significantly associated with lymph node metastasis (P=0.023) and TNM stage (P=0.008); Kaplan-Meier survival curves revealed that patients with high Gpx1 expression had worse prognoses than patients with low Gpx1 expression; By multivariate analysis, we revealed that high Gpx1 expression level (HR 2.101, 95%CI 1.011-4.367; P=0.047) was an independent prognostic factor of survival in LSCC patients.

CONCLUSION

We speculate that Gpx1 can be applied to predict the prognosis in LSCC patients.

The role of modulation of antioxidant enzyme systems in the treatment of neurodegenerative diseases

Oxidative stress is a much-appreciated phenomenon associated with the progression of neurodegenerative diseases (NDDs) due to imbalances in redox homeostasis. The poor correlations between the in vitro benefits and clinical trials of direct radical scavengers have prompted research into indirect antioxidant enzymes such as Nrf2. Activation of Nrf2 leads to the upregulation of a myriad of cytoprotective and antioxidant enzymes/proteins. Traditionally, early Nrf2-activators were studied as chemoprotective agents. There is a consequential lack of clinical trials testing Nrf2 activation in NDDs. However, there is abundant evidence of their utility in pre-clinical studies. Herein, we review the endogenous Nrf2 regulatory pathway and avenues for targeting this pathway. Furthermore, we provide updated information on pre-clinical studies for natural and synthetic Nrf2 activators. On the basis of our findings, we posit that successful therapeutics for NDDs rely on the design of potent synthetic Nrf2 activators with a careful combination of other neuroprotective activities.

Curcumin improves neurofunctions of 6-OHDA-induced parkinsonian rats

Our previous study has demonstrated that curcumin (CM), a natural ingredient isolated from Zingiberaceae, exerts the effect of inhibiting hippocampal injury in 6-hydroxydopamine (6-OHDA)-induced parkinsonian rat. However, the potential effect of CM on 6-OHDA-injured substantia nigra (SN) needs to be investigated. This study aimed to further evaluate the therapeutic effectiveness of CM against damaged SN in rats. Methodologically, Parkinson's disease (PD) rat was prepared by using a surgical approach of injecting 6-hydroxydopamine (6-OHDA) into the SN. Morris water maze, open-field assays, and rotarod test were used to assess the neurobehavioral manifestations. Neurotransmitter contents in the SN were determined by using the biochemical tests. Western blotting was employed to evaluate the target protein expressions. The representative data showed that CM protected against 6-OHDA-induced neural impairments in the SN, as evidenced by improved memory abilities, elevated intercalatum levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and reduced concentration of malonaldehyde (MDA). In addition, dopamine (DA) and acetylcholine (ACh) levels were increased in the SN. Moreover, intercalatum heat shock protein 70 (HSP70) was lowered, while basic fibroblast growth factor (bFGF), nerve growth factor (NGF) and receptor tyrosine kinase A (TrkA) expressions were up-regulated, respectively. Taken together, the findings indicate that curcum in exerts neuroprotection in the SN via ameliorating neurofunctions of PD rats.

Puerarin attenuates learning and memory impairments and inhibits oxidative stress in STZ-induced SAD mice

Puerarin (PUE), an isoflavone purified from the root of Pueraria lobata (Chinese herb), has been reported to attenuate learning and memory impairments in the transgenic mouse model of Alzheimer's disease (AD). In the present study, we tested PUE in a sporadic AD (SAD) mouse model which was induced by the intracerebroventricular injection of streptozotocin (STZ). The mice were administrated PUE (25, 50, or 100mg/kg/d) for 28 days. Learning and memory abilities were assessed by the Morris water maze test. After behavioral test, the biochemical parameters of oxidative stress (glutathione peroxidase (GSH-Px), superoxide dismutases (SOD), and malondialdehyde (MDA)) were measured in the cerebral cortex and hippocampus. The SAD mice exhibited significantly decreased learning and memory ability, while PUE attenuated these impairments. The activities of GSH-Px and SOD were decreased while MDA was increased in the SAD animals. After PUE treatment, the activities of GSH-Px and SOD were elevated, and the level of MDA was decreased. The middle dose PUE was more effective than others. These results indicate that PUE attenuates learning and memory impairments and inhibits oxidative stress in STZ-induced SAD mice. PUE may be a promising therapeutic agent for SAD.

Anti-neurotoxicity effects of oxoisoaporphine-lipoic acid hybrids

Four oxoisoaporphine-lipoic acid hybrids were designed, synthesized, and investigated in this study. To develop the hybrids, the oxoisoaporphine fragment was used for its inhibition of cholinesterases and β-amyloid (Aβ) aggregation, while the unit of lipoic acid was used for its radical-capturing and neuroprotective effects. The hybrids exhibited moderate inhibitory effects on the activity of acetylcholinesterase (AChE), with IC50 values in the micromolar range and low toxicity in SH-SY5Y cells. Moreover, the learning and memory abilities, climbing capability, and average life expectancy of the Aβ42 transgenic Drosophila were all significantly improved by the hybrids. They also enhanced the intracephalic antioxidant activity, the metabolism, and the activity cholinesterase in the flies. More strikingly, Aβ42 aggregation in the hybrids-treated Drosophila was attenuated with effective neuroprotection. Our results indicate the potential of using these oxoisoaporphine-lipoic acid hybrids in AD treatments.

Potential protection of vitamin C against liver-lesioned mice

Pathologically, liver injury can result from sustained trauma to hepatocytes, including acute damage. Thus, attenuation of hepatocellular lesion may help improve liver functions. The purpose of this study was to explore the potential advantages of vitamin C (VC) intake on acutely intralesional liver in carbon tetrachloride (CCl4)-exposed mice. Here our data showed that VC supplementation contributed to ameliorated vital signs of CCl4-lesioned mice, resulting in dose-dependent reduction of hepatomegaly. VC lowered the levels of liver functional enzymes including alanine aminotransferase (ALT) and glutamic-oxaloacetic transaminase (AST) in serum, while concentration of lactic acid concentration in blood plasma was decreased. VC-administered CCl4-lesioned mice manifested increased activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), while the malondialdehyde (MDA) content was reduced in liver tissue. Moreover, VC consumption attenuated hepatotoxic injuries of CCl4-lesioned mice, in which the number of TNF-α positive cells was dose-dependently reduced. Furthermore, intrahepatic expression of TRL-4 mRNA, a vital inflammation-regulator, was down-regulated in VC-administered mice. Overall, we conclude that VC has the potentiality of anti-hepatotoxicity that is capable of ameliorating liver functions, speculating that therapeutic mechanism relates to normalizing metabolism and blocking inflammatory stress in the liver.

Identification of tanshinone IIA as a natural monoacylglycerol lipase inhibitor by combined in silico and in vitro approach

Tanshinone IIA was identified as a novel natural MAGL inhibitor by an in silico approach combined with in vitro experimental analysis.

Advances in neuroprotective ingredients of medicinal herbs by using cellular and animal models of Parkinson's disease

Parkinson's disease (PD) is a multifactorial disorder, which is neuropathologically identified by age-dependent neurodegeneration of dopaminergic neurons in the substantia nigra. Development of symptomatic treatments has been partly successful for PD research, but there remain a number of inadequacies in therapeutic strategies for the disease. The pathogenesis of PD remains intricate, and the present anti-PD treatments appears to be clinically insufficient. Comprehensive research on discovery of novel drug candidates has demonstrated that natural products, such as medicinal herbs, plant extracts, and their secondary metabolites, have great potential as therapeutics with neuroprotective activity in PD. Recent preclinical studies suggest that a number of herbal medicines and their bioactive ingredients can be developed into optimum pharmaceuticals for treating PD. In many countries, traditional herbal medicines are used to prevent or treat neurodegenerative disorders, and some have been developed as nutraceuticals or functional foods. Here we focus on recent advances of the evidence-linked neuroprotective activity of bioactive ingredients of herbal origin in cellular and animal models of PD research.