Anti-inflammatory effects of total isoflavones from Pueraria lobata on cerebral ischemia in rats

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.

Constituent isoflavones of Puerariae radix as a potential neuroprotector in cognitive impairment: Evidence from preclinical studies

With the increasing aging population worldwide, the incidence of senile cognitive impairment (CI) is increasing, posing a serious threat to the health of elderly persons. Despite developing new drugs aimed at improving CI, progress in this regard has been insufficient. Natural preparations derived from plants have become an unparalleled resource for developing new drugs. Puerariae radix (PR) has a long history as Chinese herbal medicine. PR is rich in various chemical components such as isoflavones, triterpenes, and saponins. The isoflavones (puerarin, daidzein, formononetin, and genistein) exhibit potential therapeutic effects on CI through multiple mechanisms. Relevant literature was organized from major scientific databases such as PubMed, Elsevier, SpringerLink, ScienceDirect, and Web of Science. Using "Puerariae radix," "Pueraria lobata," "isoflavones," "puerarin," "antioxidant," "daidzein," "formononetin," "genistein," "Alzheimer"s disease," and "vascular cognitive impairment" as keywords, the relevant literature was extracted from the databases mentioned above. We found that isoflavones from PR have neuroprotective effects on multiple models of CI via multiple targets and mechanisms. These isoflavones prevent Aβ aggregation, inhibit tau hyperphosphorylation, increase cholinergic neurotransmitter levels, reduce neuroinflammation and oxidative stress, improve synaptic plasticity, promote nerve regeneration, and prevent apoptosis. PR has been used as traditional Chinese herbal medicine for a long time, and its constituent isoflavones exert significant therapeutic effects on CI through various neuroprotective mechanisms. This review will contribute to the future development of isoflavones present in PR as novel drug candidates for the clinical treatment of CI.

The mechanism of intestinal microbiota regulating immunity and inflammation in ischemic stroke and the role of natural botanical active ingredients in regulating intestinal microbiota: A review

Intestinal microbiota is a unique ecosystem, known as the "second genome" of human beings. With the widespread application of next generation sequencing (NGS), especially 16 S rRNA and shotgun sequencing, numerous studies have shown that dysregulation of intestinal microbiota is associated with many central nervous system diseases. Ischemic stroke (IS) is a cerebrovascular disease with high morbidity and mortality. Brain damage in IS affects intestinal function, and intestinal dysfunction further aggravates brain damage, forming a vicious circle of mutual interference in pathology. The microbiota-gut-brain axis study based on the intestinal microbiota has opened up broader ideas for exploring its pathogenesis and risk factors, and also provided more possibilities for the selection of therapeutic targets for this type of drug. This review discussed the application of NGS technology in the study of intestinal microbiota and the research progress of microbiota-gut-brain axis in recent years, and systematically sorts out the literature on the relationship between ischemic stroke and intestinal microbiota. It starts with the characteristics of microbiota-gut-brain axis' bidirectional regulation, respectively discusses the high risk factors of IS under intestinal microbiota imbalance and the physiological and pathological changes of intestinal microbiota after IS, and summarizes the related targets, in order to provide reliable reference for the treatment of IS from intestinal microbiota. In addition, natural botanical active ingredients have achieved good results in the treatment of IS based on regulating the homeostasis of gut microbiota, providing new evidence for studying the potential targets and therapies of IS based on the microbiota-gut-brain axis.

An Analysis of the Plant- and Animal-Based Hydrocolloids as Byproducts of the Food Industry

Hydrocolloids are naturally occurring polysaccharides or proteins, which are used to gelatinize, modify texture, and thicken food products, and are also utilized in edible films and drug capsule production. Moreover, several hydrocolloids are known to have a positive impact on human health, including prebiotics rich in bioactive compounds. In this paper, plant-derived hydrocolloids from arrowroot (Maranta arundinacea), kuzu (Pueraria montana var lobata), Sassafras tree (Sassafras albidum) leaves, sugarcane, acorn, and animal-derived gelatin have been reviewed. Hydrocolloid processing, utilization, physicochemical activities, composition, and health benefits have been described. The food industry generates waste such as plant parts, fibers, residue, scales, bones, fins, feathers, or skin, which are often discarded back into the environment, polluting it or into landfills, where they provide no use and generate transport and storage costs. Food industry waste frequently contains useful compounds, which can yield additional income if acquired, thus decreasing the environmental pollution. Despite conventional manufacturing, the aforementioned hydrocolloids can be recycled as byproducts, which not only minimizes waste, lowers transportation and storage expenses, and boosts revenue, but also enables the production of novel, functional, and healthy food additives for the food industry worldwide.

Bioassay-Guided Characterization, Antioxidant, Anti-Melanogenic and Anti-Photoaging Activities of Pueraria thunbergiana L. Leaf Extracts in Human Epidermal Keratinocytes (HaCaT) Cells

Although the roots and flowers of P. thunbergiana are known to have various physiologically active effects, studies on the anti-melanin production and anti-photoaging effects of its leaf extracts and cellular mechanisms are still lacking. In this study, we evaluated the possibility of using Pueraria thunbergiana leaves as a natural material for skin whitening and anti-aging-related functional cosmetics. The 30% ethyl alcohol (EtOH) extract from P. thunbergiana leaves was fractionated using n-hexane, ethyl acetate (EtOAc), butanol, and aqueous solution to measure their whitening, and anti-aging effects. The EtOAc fraction contained a high content of phenolic and flavonoids and showed higher 1,1-diphenyl-2-picryhydrazyl (DPPH) and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activities than the other fractions. It was also confirmed that the EtOAc fraction markedly inhibited α-melanocyte stimulating hormone (α-MSH)-induced melanogenesis in B16F10 melanoma cells. In addition, the EtOAc fraction showed a protective effect against ultraviolet B (UVB) in HaCaT cells and increased the collagen synthesis that was decreased due to UVB exposure. Matrix metalloproteinase-1 (MMP-1) activity and MMP-1 protein expression were reduced in human epidermal keratinocytes (HaCaT) cells. These results indicate that the EtOAc fraction has superior antioxidant activity, anti-melanogenesis, and anti-photoaging effects compared to the other fractions. Therefore, in this study, we confirmed the potential of P. thunbergiana leaf extract as a functional cosmetic ingredient, and it can be used as basic data for the physiological activity of P. thunbergiana leaf extracts.

Uncovering the Mechanism of Chuanhong Stroke Capsule in the Treatment of Stroke Based on Network Pharmacology and Molecular Docking Technology

Background and Objective: Chuanhong Stroke Capsule (CHSC) has good clinical efficacy in the treatment of cerebral ischemic stroke (CIS) patients. This study aimed to investigate the pharmacological mechanisms of CHSC in treating CIS using bioinformatics. Methods: The active compounds of CHSC were screened by searching Traditional Chinese Medicine System Pharmacological Database and Analysis Platform (TCMSP), Swiss absorption, distribution, metabolism, and excretion (ADME), PubMed, and China National Knowledge Infrastructure (CNKI) databases. Besides, the potential targets of active compounds were obtained through TCMSP and Swiss Target Prediction databases. CIS targets were obtained from GeneCards, Online Mendelian Inheritance in Man (OMIM), and Gene Expression Omnibus (GEO) databases. CHSC-CIS intersection targets were identified by matching the two, and prediction and analysis of biological functions and pathways of intersection targets was used the enrichments of gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Furthermore, protein–protein interaction (PPI) network, herb-target, and compound-target network of CHSC-CIS were constructed by Cytoscape3.7.2, and herb-compound-pathway network was drawn with Sankey diagram. Finally, AutoDock was used for molecular docking verification, and identifying the active binding sites in target proteins. Results: A total of 293 putative targets were obtained from 62 active compounds in CHSC. Among them, 209 targets were related to CIS. PPI network showed that the top 16 key targets were RELA, JUN, FOS, MAPK1, AKT1, etc. KEGG pathway enrichment analysis demonstrated that CHSC was enriched in PI3K-Akt, MAPK, and TNF signaling pathways. In addition, GO enrichment analysis showed the significant enrichment of CHSC in the following categories: kinase binding, cellular response to nitrogen compound, etc. Network topology analysis showed that quercetin, luteolin, kaempferol, etc., were the key components in CHSC. Finally, molecular docking studies suggested that the active components in CHSC had a good binding ability with the key targets. Conclusions: Our study demonstrated that CHSC exerted the effect in treating CIS by the characteristics of multi-target and multi-pathway, thereby providing a theoretical basis for further study of the effective components and mechanism of CHSC in the treatment of CIS.

The Positive Influence of Polyphenols Extracted From Pueraria lobata Root on the Gut Microbiota and Its Antioxidant Capability

Pueraria lobata, an edible food and medicinal plant, is a rich source of bioactive components. In this study, a polyphenol-rich extract was isolated from P. lobata. Puerarin was identified, and the high antioxidant bioactivity of the P. lobata extract was evaluated using the methods of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS), and hydroxyl free radical scavenging ratio. Additionally, the IC₅₀ values of DPPH, ABTS, and hydroxyl radical scavenging activities were 50.8, 13.9, and 100.4 μg/ml, respectively. Then, the P. lobata extract was administered to C57Bl/6J mice and confirmed to have a superior effect on enhancing the antioxidant status including improving superoxide dismutase activity, glutathione peroxidase peroxide activity, total antioxidant capacity activity, and malondialdehyde contents in vivo. Furthermore, the P. lobata extract had beneficial and prebiotic effects on the composition and structure of gut microbiota. Results showed that the P. lobata extract significantly increased the abundance of beneficial bacteria, involving Lactobacillaceae and Bacteroidetes, and decreased the abundance of Ruminococcaceae, Prevotellaceae, and Burkholderiaceae. Overall, our results provided a basis for using the P. lobata extract as a promising and potential functional ingredient for the food industry.

The mechanism of microglia-mediated immune inflammation in ischemic stroke and the role of natural botanical components in regulating microglia: A review

Ischemic stroke (IS) is one of the most fatal diseases. Neuroimmunity, inflammation, and oxidative stress play important roles in various complex mechanisms of IS. In particular, the early proinflammatory response resulting from the overactivation of resident microglia and the infiltration of circulating monocytes and macrophages in the brain after cerebral ischemia leads to secondary brain injury. Microglia are innate immune cells in the brain that constantly monitor the brain microenvironment under normal conditions. Once ischemia occurs, microglia are activated to produce dual effects of neurotoxicity and neuroprotection, and the balance of the two effects determines the fate of damaged neurons. The activation of microglia is defined as the classical activation (M1 type) or alternative activation (M2 type). M1 type microglia secrete pro-inflammatory cytokines and neurotoxic mediators to exacerbate neuronal damage, while M2 type microglia promote a repairing anti-inflammatory response. Fine regulation of M1/M2 microglial activation to minimize damage and maximize protection has important therapeutic value. This review focuses on the interaction between M1/M2 microglia and other immune cells involved in the regulation of IS phenotypic characteristics, and the mechanism of natural plant components regulating microglia after IS, providing novel candidate drugs for regulating microglial balance and IS drug development.

Neuroprotective Mechanisms of Puerarin in Central Nervous System Diseases: Update

Due to global population aging and modern lifestyle changes, the incidence of central nervous system (CNS) disorders, such as neurodegenerative diseases, neuropsychiatric disorders, and cerebrovascular diseases, is increasing and has become a major public health challenge. Current medications commonly used in the clinic are far from satisfactory and may cause serious side effects. Therefore, the identification of novel drugs for the effective management of CNS diseases is very urgent. Puerarin, a highly bioactive ingredient isolated from Pueraria lobata, is known to possess a broad spectrum of pharmacological properties including anti-diabetic, anti-inflammatory, anti-antioxidant, neuroprotective, and cardioprotective features. However, its clinical application is limited due to its poor water solubility. Since puerarin has demonstrated a wide range of neuroprotective functions in various CNS diseases, such as Alzheimer’s disease, Parkinson’s disease, cerebral ischemia, depression, and spinal cord injury, it has been attracting increasingly intense attention worldwide. In this review, we intend to extensively summarize the research progress on neuroprotective mechanisms of puerarin in recent years and discuss the future directions of its application in CNS disease treatment.

SR-5, the specific ratio of Korean multi-herbal formula: An evaluation of antiulcerogenic effects on experimentally induced gastric ulcers in mice

Purpose

Previously, we demonstrated that the specific ratio of Korean multi-herbal formula (SR-5) exhibits hepatoprotective properties against ethanol-induced hepatic damage in rats. Chronic and excessive alcohol consumption is a major etiological factor involved in gastric disease and ulcer development induced by the inflammatory response and oxidative stress.

Methods

The present study evaluated the gastroprotective effects of SR-5 (100, 150, and 200 mg/kg) against hydrochloride acid/ethanol (HCl/EtOH)-induced and indomethacin/hydrochloride acid (INDO/HCl)-induced gastritis in a mouse model and the mechanisms involved.

Results

All the tested doses of SR-5 significantly inhibited gastric lesions in the HCl/EtOH-induced ulcer model mice. Similarly, all the tested doses of SR-5 significantly inhibited gastric lesions in the INDO/HCl-induced ulcer model mice. Furthermore, mice pretreated with SR-5 had significantly increased gastric levels of enzymatic and nonenzymatic antioxidants, namely, catalase (CAT) and glutathione (GSH), with concomitant reductions in malondialdehyde (MDA) and reactive oxygen species (ROS) levels compared with those in the HCl/EtOH or INDO/HCl group. SR-5 suppressed the expression of nuclear factor-kappa B (NF-κB)/p65, inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), and cyclooxygenase-2 (COX-2) to their normal values.

Conclusion

These findings are the first to demonstrate the powerful protective effect of SR-5 against gastric injury development and provide hope for clinical application.

From Menopause to Neurodegeneration-Molecular Basis and Potential Therapy

The impacts of menopause on neurodegenerative diseases, especially the changes in steroid hormones, have been well described in cell models, animal models, and humans. However, the therapeutic effects of hormone replacement therapy on postmenopausal women with neurodegenerative diseases remain controversial. The steroid hormones, steroid hormone receptors, and downstream signal pathways in the brain change with aging and contribute to disease progression. Estrogen and progesterone are two steroid hormones which decline in circulation and the brain during menopause. Insulin-like growth factor 1 (IGF-1), which plays an import role in neuroprotection, is rapidly decreased in serum after menopause. Here, we summarize the actions of estrogen, progesterone, and IGF-1 and their signaling pathways in the brain. Since the incidence of Alzheimer’s disease (AD) is higher in women than in men, the associations of steroid hormone changes and AD are emphasized. The signaling pathways and cellular mechanisms for how steroid hormones and IGF-1 provide neuroprotection are also addressed. Finally, the molecular mechanisms of potential estrogen modulation on N-methyl-d-aspartic acid receptors (NMDARs) are also addressed. We provide the viewpoint of why hormone therapy has inconclusive results based on signaling pathways considering their complex response to aging and hormone treatments. Nonetheless, while diagnosable AD may not be treatable by hormone therapy, its preceding stage of mild cognitive impairment may very well be treatable by hormone therapy.

Protective Effect of Natural Products against Huntington's Disease: An Overview of Scientific Evidence and Understanding Their Mechanism of Action

Huntington's disease (HD), a neurodegenerative disease, normally starts in the prime of adult life, followed by a gradual occurrence of characteristic psychiatric disturbances and cognitive and motor dysfunction. To the best of our knowledge, there is no treatment available to completely mitigate the progression of HD. Among various therapeutic approaches, exhaustive literature reports have confirmed the medicinal benefits of natural products in HD experimental models. Building on this information, this review presents a brief overview of the neuroprotective mechanism(s) of natural products against in vitro/in vivo models of HD. Relevant studies were identified from several scientific databases, including PubMed, ScienceDirect, Scopus, and Google Scholar. After screening through literature from 2005 to the present, a total of 14 medicinal plant species and 30 naturally isolated compounds investigated against HD based on either in vitro or in vivo models were included in the present review. Behavioral outcomes in the HD in vivo model showed that natural compounds significantly attenuated 3-nitropropionic acid (3-NP) induced memory loss and motor incoordination. The biochemical alteration has been markedly alleviated with reduced lipid peroxidation, increased endogenous enzymatic antioxidants, reduced acetylcholinesterase activity, and increased mitochondrial energy production. Interestingly, following treatment with certain natural products, 3-NP-induced damage in the striatum was ameliorated, as seen histologically. Overall, natural products afforded varying degrees of neuroprotection in preclinical studies of HD via antioxidant and anti-inflammatory properties, preservation of mitochondrial function, inhibition of apoptosis, and induction of autophagy.

Efficacy of Getong Tongluo Capsule () for Convalescent-Phase of Ischemic Stroke and Primary Hypertension: A Multicenter, Randomized, Double-Blind, Controlled Trial

OBJECTIVE

To evaluate whether the efficacy of Getong Tongluo Capsule (, GTC, consisted of total flavone of Radix Puerariae) on improving patients' quality of life and lowering blood pressure are superior to the extract of Ginkgo biloba (EGB) for patients with convalescent-phase ischemic stroke and primary hypertension.

METHODS

This randomized, positive-drug- and placebo-controlled, double-blind trial was conducted from September 2015 to October 2017. Totally 477 eligible patients from 18 hospitals in China were randomly assigned in a 2:1:1 ratio to the following interventions, twice a day for 12 weeks: (1) GTC 250 mg plus EGB-matching placebo 40 mg (237 cases, GTC group), (2) EGB 40 mg plus GTC-matching placebo 250 mg (120 cases, EGB group) or (3) GTC-matching placebo 250 mg plus EGB-matching placebo 40 mg (120 cases, placebo group). Moreover, all patients were orally administered aspirin enteric-coated tablets 100 mg, once a day for 12 weeks. The primary outcome was the Barthel Index (BI). The secondary outcomes included the control rate of blood pressure and National Institutes of Health Stroke Scale (NIHSS) scores. The incidence and severity of adverse events (AEs) were calculated and assessed.

RESULTS

The BI relative independence rates, the clinical recovery rates of NIHSS, and the total effective rates of NIHSS in the GTC and EGB groups were significantly higher than the placebo group at 12 weeks after treatment (P<0.05), and no statistical significance was found between the GTC and EGB groups (P>0.05). The control rate of blood pressure in the GTC group was significantly higher than the EGB and placebo groups at 12, 18 and 24 weeks after treatment (P<0.01). There were no statistically significant differences in the incidences of AEs, adverse drug reactions, or serious AEs among the 3 groups (P>0.05).

CONCLUSION

GTC exhibited significant efficacy in improving patients' quality of life as well as neurological function and controlling hypertension. (Registration No. ChiCTR1800016667).

Pueraria lobata and Daidzein Reduce Cytotoxicity by Enhancing Ubiquitin-Proteasome System Function in SCA3-iPSC-Derived Neurons

Spinocerebellar ataxia type 3 (SCA3) is an autosomal dominant neurodegenerative disorder caused by a CAG repeat expansion within the ATXN3/MJD1 gene. The expanded CAG repeats encode a polyglutamine (polyQ) tract at the C-terminus of the ATXN3 protein. ATXN3 containing expanded polyQ forms aggregates, leading to subsequent cellular dysfunctions including an impaired ubiquitin-proteasome system (UPS). To investigate the pathogenesis of SCA3 and develop potential therapeutic strategies, we established induced pluripotent stem cell (iPSC) lines from SCA3 patients (SCA3-iPSC). Neurons derived from SCA3-iPSCs formed aggregates that are positive to the polyQ marker 1C2. Treatment with the proteasome inhibitor, MG132, on SCA3-iPSC-derived neurons downregulated proteasome activity, increased production of radical oxygen species (ROS), and upregulated the cleaved caspase 3 level and caspase 3 activity. This increased susceptibility to the proteasome inhibitor can be rescued by a Chinese herbal medicine (CHM) extract NH037 (from Pueraria lobata) and its constituent daidzein via upregulating proteasome activity and reducing protein ubiquitination, oxidative stress, cleaved caspase 3 level, and caspase 3 activity. Our results successfully recapitulate the key phenotypes of the neurons derived from SCA3 patients, as well as indicate the potential of NH037 and daidzein in the treatment for SCA3 patients.

Association between Dietary Isoflavone Intake and Ulcerative Colitis Symptoms in Polish Caucasian Individuals

Currently there are contradictory observations regarding the associations between the isoflavone intake and inflammatory bowel disease in terms of its prevention and treatment, and this may be attributed to the diversity of applied doses and influence of various isoflavones. The aim of the presented cross-sectional study is to analyze the association between intake of various isoflavones (daidzein, genistein, glicytein and total isoflavones) and ulcerative colitis symptoms (fecal blood, mucus and pus) in Polish Caucasian individuals in confirmed remission. Assessment of diet was based on self-reported data obtained from patients' three-day dietary records and their individual assessments of symptoms. A total of 56 Caucasian patients with ulcerative colitis in confirmed remission were recruited for the study (37 females and 19 males, aged 18-80). For individuals with no fecal mucus observed, higher daidzein (p = 0.035, 122 vs. 19 µg) and total isoflavone intakes (p = 0.034, 302.2 vs. 123.7 µg) were observed in comparison with individuals not declaring this symptom, while for daidzein it was confirmed for the component density of their diets. The opposite association was stated for fecal pus, as for individuals with a lack of this symptom, lower daidzein intake was stated in comparison with individuals declaring this symptom (p = 0.049, 103.3 vs. 206.7 µg), but it was not confirmed for the component density of the diets. It was stated that the high intake of isoflavones by Caucasian individuals, as in a western diet, may influence the symptoms of ulcerative colitis, with the strongest influence by daidzein. Taking this into account, isoflavones may be included into the diets of ulcerative colitis patients in remission if well-tolerated, but there is a need for further study.

Simultaneous separation and determination of seven isoflavones in Radix Puerariae by capillary electrophoresis with a dual cyclodextrin system

A simple, comprehensive and efficient capillary electrophoresis method using a dual cyclodextrin system was developed for the simultaneous determination of seven isoflavones (3'-methoxypuerarin, puerarin, 3'-hydroxypuerarin, ononin, daidzin, daidzein and genistin). Baseline separations of the seven isoflavones were achieved within 11 min with the running buffer consisting of 35 mm sodium tetraborate, 9.0 mm sulfobutylether-β-cyclodextrin and 30 mm α-cyclodextrin at pH 9.34, and peaks were detected at 254 nm. Other separation parameters included the separation voltage for 15 kV and the working temperature for 25°C. Under the optimum conditions, good linearities were obtained with linear correlation coefficients of seven isoflavones of 0.9978-0.9992. The limits of detection and the limits of quantification were 0.7-2.9 and 2.5-9.5 μg/mL, respectively. Excellent precision and accuracy were obtained. The intraday and interday precision ranged from 0.7 to 2.0% and from 0.8 to 1.9%, respectively. The recoveries of seven analytes were from 97.7 to 103.1%. This method was successfully applied to determine the seven analytes in Radix Puerariae and its preparations.

Total Flavonoids in Caragana (TFC) Promotes Angiogenesis and Enhances Cerebral Perfusion in a Rat Model of Ischemic Stroke

Previous studies have demonstrated that total flavonoid extracts from Caragana sinica (TFC) exert multiple therapeutic effects, promote blood flow, and exhibit anti-inflammatory and antioxidant properties. The present study aimed to investigate whether TFC promotes angiogenesis and exerts neuroprotective effects in a rat model of transient middle cerebral artery occlusion (tMCAO). Male Wistar rats were subjected to tMCAO for 1.5 h, followed by 24 h of reperfusion. TFC (15, 30, 60 mg/kg) was administered for 14 days. Evaluations of neurological function were performed following reperfusion, and infarct volumes were assessed in brain slices stained with 2,3,5-triphenyltetrazolium chloride (TTC). Our results indicated that TFC significantly attenuated cerebral infarct volume and neurological deficits following tMCAO. Laser Doppler, micro-PET/CT, and MRI analyses further demonstrated that TFC reduced infarct volume and enhanced cerebral blood flow in a dose-dependent manner, with the most significant effects occurring at a concentration of 60 mg/kg. Significant up-regulation of CD31, VEGF, Ang-1, HIF-1α, delta-like 4 (Dll4), and Notch1 expression was also observed in the experimental groups, relative to that in the vehicle group. In summary, the results of the present study indicate that TFC (15, 30, 60 mg/kg) attenuates neurological deficits, reduces infarct volume, and promotes angiogenesis following MCAO in a concentration-dependent manner, likely via increases in the expression of CD31, VEGF, Ang-1, HIF-1α, Dll4, and Notch1. Further studies are required to determine the clinical usefulness and potential mechanisms of TFC in patients with cerebral focal ischemic stroke.

Pretreated Glehnia littoralis Extract Prevents Neuronal Death Following Transient Global Cerebral Ischemia through Increases of Superoxide Dismutase 1 and Brain-derived Neurotrophic Factor Expressions in the Gerbil Hippocampal Cornu Ammonis 1 Area

BACKGROUND

Glehnia littoralis, as a traditional herbal medicine to heal various health ailments in East Asia, displays various therapeutic properties including antioxidant effects. However, neuroprotective effects of G. littoralis against cerebral ischemic insults have not yet been addressed. Therefore, in this study, we first examined its neuroprotective effects in the hippocampus using a gerbil model of transient global cerebral ischemia (TGCI).

METHODS

Gerbils were subjected to TGCI for 5 min. G. littoralis extract (GLE; 100 and 200 mg/kg) was administrated orally once daily for 7 days before ischemic surgery. Neuroprotection was examined by neuronal nuclear antigen immunohistochemistry and Fluoro-Jade B histofluorescence staining. Gliosis was observed by immunohistochemistry for glial fibrillary acidic protein and ionized calcium-binding adapter molecule 1. For neuroprotective mechanisms, immunohistochemistry for superoxide dismutase (SOD) 1 and brain-derived neurotrophic factor (BDNF) was done.

RESULTS

Pretreatment with 200 mg/kg of GLE protected pyramidal neurons in the cornu ammonis 1 (CA1) area from ischemic insult area (F = 29.770, P < 0.05) and significantly inhibited activations of astrocytes (F = 22.959, P < 0.05) and microglia (F = 44.135, P < 0.05) in the ischemic CA1 area. In addition, pretreatment with GLE significantly increased expressions of SOD1 (F = 28.561, P < 0.05) and BDNF (F = 55.298, P < 0.05) in CA1 pyramidal neurons of the sham- and ischemia-operated groups.

CONCLUSIONS

Our findings indicate that pretreatment with GLE can protect neurons from ischemic insults, and we suggest that its neuroprotective mechanism may be closely associated with increases of SOD1 and BDNF expressions as well as attenuation of glial activation.

Development of a liquid chromatography-tandem mass spectrometry method for simultaneous determination of five isoflavonoids and seven neurochemicals in rat brain dialysate and its application to a pharmacological study

Pueraria lobata is a medicinal plant widely used in traditional Chinese medicine. The total pueraria isoflavones have demonstrated positive effect against neurological disorders. In the present study, we first develop an ultra high performance liquid chromatography and tandem mass spectrometry method to quantify the multiple active pueraria isoflavonoids and neurochemical markers in brain dialysate to provide tools for further exploring the functional mechanism of pueraria isoflavones for neuroactivities. A phenomenex Luna C18 column (50 × 2.0 mm, 5 μm) was employed with acetonitrile/0.05% formic acid in water as the mobile phase for the separation of analytes. A mass spectrometer with electrospray ionization source in positive/negative ion switching mode was used for multiple reaction monitoring of the detected compounds. The method was validated and proved acceptable. The intra- and interday precision across quality control levels was within 13.87 for all analytes, whereas the deviation of assay accuracies ranged between 0.03 and 11.53%. The method was successfully applied to a pharmacological study of pueraria isoflavones in rat brain.

Pretreatment with Shuanghe-Tang Extract Attenuates Postischemic Brain Injury and Edema in a Mouse Model of Stroke: An Analysis of Medicinal Herbs Listed in Dongui Bogam

Aim

Although stroke is among the leading causes of death and long-term disability, there are few effective treatments for limiting the severity of neurological sequelae. We evaluated the effects of 29 medicinal herbs listed in the Pung chapter of the 17th century Korean medical text Dongui Bogam on stroke symptoms in a mouse model of cerebral ischemia.

Methods

Focal cerebral ischemia was induced via photothrombosis. Infarct volume, brain edema, and neurological deficits were evaluated. Immunofluorescence staining for tight junction proteins and aquaporin 4 (AQP4) was performed following ischemic injury.

Results

Based on our initial findings, we examined the effects of two prescriptions in which the candidate herbs comprised more than 60% of the total formula: Shuanghe-tang and Zengsunsiwu-tang. Pretreatment with Shuanghe-tang significantly reduced infarct volume, decreased blood-brain barrier (BBB) breakdown, attenuated edema, and improved neurological and motor functions in a dose-dependent manner (30, 100, and 300 mg/kg), while no such effects were observed in mice pretreated with Zengsunsiwu-tang. Immunohistochemical analysis revealed significant increases in ipsilateral occludin and zonula occludens 1 (ZO-1) expression in Shuanghe-tang-pretreated mice, as well as increased AQP4 immunofluorescence.

Conclusions

These results indicate that Shuanghe-tang may protect against brain injury and promote recovery of neurological function following ischemia.

Extraction of isoflavones from Puerariae lobata using subcritical water

As an alternative to organic solvents, subcritical water was employed for the first time as an effective solvent for the extraction of isoflavones from Puerariae lobata. Optimum experimental conditions for the extraction of the four main isoflavones were established by single factor experiments, and the optimum experimental conditions for total isoflavone extraction were established further by response surface methodology. With an extraction time of 45 min and a liquid/solid ratio of 1 : 20, the extraction yields of puerarin, 3′-methoxypuerarin, and daidzin reached maxima at extraction temperatures of 120 °C, 140 °C and 200 °C, respectively. Moreover, puerarin, 3′-methoxypuerarin and daidzin were degraded and produced various byproducts due to hydrothermal reactions at higher temperatures. The maximum extraction yields of the total isoflavones were obtained by response surface methodology (extraction time of 45 min, solid/liquid ratio of 1 : 15 and extraction temperature of 120 °C). Compared to conventional solvents, subcritical water utilized less solvent and required a shorter extraction time.

Four main isoflavones from Puerariae lobata were successfully extracted using subcritical water. Maximum yields of total isoflavones by response surface methodology were obtained.

Puerarin protects rat brain against ischemia/reperfusion injury by suppressing autophagy via the AMPK-mTOR-ULK1 signaling pathway

Puerarin suppresses autophagy to alleviate cerebral ischemia/reperfusion injury, and accumulating evidence indicates that the AMPK-mTOR signaling pathway regulates the activation of the autophagy pathway through the coordinated phosphorylation of ULK1. In this study, we investigated the mechanisms underlying the neuroprotective effect of puerarin and its role in modulating autophagy via the AMPK-mTOR-ULK1 signaling pathway in the rat middle cerebral artery occlusion model of cerebral ischemia/reperfusion injury. Rats were intraperitoneally injected with puerarin, 50 or 100 mg/kg, daily for 7 days. Then, 30 minutes after the final administration, rats were subjected to transient middle cerebral artery occlusion for 90 minutes. Then, after 24 hours of reperfusion, the Longa score and infarct volume were evaluated in each group. Autophagosome formation was observed by transmission electron microscopy. LC3, Beclin-1 p62, AMPK, mTOR and ULK1 protein expression levels were examined by immunofluorescence and western blot assay. Puerarin substantially reduced the Longa score and infarct volume, and it lessened autophagosome formation in the hippocampal CA1 area following cerebral ischemia/reperfusion injury in a dose-dependent manner. Pretreatment with puerarin (50 or 100 mg/kg) reduced Beclin-1 expression and the LC3-II/LC3-I ratio, as well as p-AMPK and pS317-ULK1 levels. In comparison, it increased p62 expression. Furthermore, puerarin at 100 mg/kg dramatically increased the levels of p-mTOR and pS757-ULK1 in the hippocampus on the ischemic side. Our findings suggest that puerarin alleviates autophagy by activating the APMK-mTOR-ULK1 signaling pathway. Thus, puerarin might have therapeutic potential for treating cerebral ischemia/reperfusion injury.

Compound of icariin, astragalus, and puerarin mitigates iron overload in the cerebral cortex of Alzheimer's disease mice

Increasing evidence indicates that disruption of normal iron homeostasis may contribute to pathological development of Alzheimer's disease. Icariin, astragalus, and puerarin have been shown to suppress iron overload in the cerebral cortex and improve spatial learning and memory disorders in Alzheimer's disease mice, although the underlying mechanism remains unclear. In the present study, APPswe/PS1ΔE9 transgenic mice were administered icariin, astragalus, and puerarin (120, 80, and 80 mg/kg, respectively, once a day, for 3 months). Iron levels were detected by flame atomic absorption spectroscopy. Interleukin-1β, interleukin-6, and tumor necrosis factor-α levels were measured in the cerebral cortex by enzyme linked immunosorbent assay. Glutathione peroxidase and superoxide dismutase activity and malondialdehyde content were determined by colorimetry. Our results demonstrate that after treatment, iron levels and malondialdehyde content are decreased, while glutathione peroxidase and superoxide dismutase activities are increased. Further, interleukin-1β, interleukin-6, and tumor necrosis factor-α levels were reduced. These results confirm that compounds of icariin, astragalus, and puerarin may alleviate iron overload by reducing oxidative stress and the inflammatory response.

Antioxidant and Anti-Inflammatory Effects of Herbal Formula SC-E3 in Lipopolysaccharide-Stimulated RAW 264.7 Macrophages

SC-E3 is a novel herbal formula composed of five oriental medicinal herbs that are used to treat a wide range of inflammatory diseases in Korean traditional medicine. In this study, we sought to determine the effects of SC-E3 on free radical generation and inflammatory response in lipopolysaccharide- (LPS-) treated RAW 264.7 macrophages and the molecular mechanism involved. The ethanol extract of SC-E3 showed good free radical scavenging activity and inhibited LPS-induced reactive oxygen species generation. SC-E3 significantly inhibited the production of the LPS-induced inflammatory mediators, nitric oxide and prostaglandin E₂, by suppressing the expressions of inducible nitric oxide synthase and cyclooxygenase-2, respectively. SC-E3 also prevented the secretion of the proinflammatory cytokines, IL-1β, TNF-α, and IL-6, and inhibited LPS-induced NF-κB activation and the mitogen-activated protein kinase (MAPK) pathway. Furthermore, SC-E3 induced the expression of heme oxygenase-1 (HO-1) by promoting the nuclear translocation and transactivation of Nrf2. Taken together, these results suggest that SC-E3 has potent antioxidant and anti-inflammatory effects and that these effects are due to the inhibitions of NF-κB and MAPK and the induction of Nrf2-mediated HO-1 expression in macrophages. These findings provide scientific evidence supporting the potential use of SC-E3 for the treatment and prevention of various inflammatory diseases.

Brain Pharmacokinetics and the Pharmacological Effects on Striatal Neurotransmitter Levels of Pueraria lobata Isoflavonoids in Rat

Isoflavonoids are putatively active components of Pueraria lobata and has been demonstrated prominent neuro-protection effect against cerebrovascular disorders, hypertension or Parkinson's disease (PD). However, the molecular basis for the beneficial effect of Pueraria lobata on nervous systems has not been well revealed. The present study aims to assess striatum exposure to main active isoflavonoids and changes of striatal extracellular neurotransmitters levels in rat brain after intravenous administration of Pueraria lobata isoflavonoids extracts (PLF), to further elucidate its' substantial bases for neuro activities. Fifteen rats were divided into 3 groups (five rats in each group) to receive a dose of PLF at 80 or 160 mg/kg or normal saline (vehicle), respectively. An LC-MS/MS method was employed to determine the concentrations of five main isoflavonoids and multiple neurotransmitters in microdialysate from striatal extracellular fluid (ECF) of the rats. The exposed quantities of puerarin (PU), 3′-methoxypuerarin (MPU), daidzein-8-C-apiosyl-(1-6)-glucoside (DAC), and 3′-hydroxypuerarin (HPU) in striatum were dose-dependent. The content of daidzein (DAZ) was too low to be detected in all dialysate samples through the experiment. Optimal dose PLF (80 mg/kg) promoted DA metabolism and inhibited 5-HT metabolism. No obvious change in the level of GLu was determined. The concentration of GABA presented a temporary decline firstly and then a gradual uptrend followed by a further downtrend. Higher dose (160 mg/kg) PLF could enhance the metabolism of both DA and 5-HT, and lower the extracellular level of GLu, without changing GABA concentrations, which might result in alleviation on excitatory toxicity under conditions, such as ischemia. The results infer that different dose of PLF should be chosen to achieve appropriate neurochemical modulation effects under conditions, such as hypertension or ischemia/stroke. These findings may significantly contribute to a better understanding of the neuroprotective effect of Pueraria lobata and provide new insights into its application toward neuro-degenerative diseases in the future.

Effects of puerarin combined with conventional therapy on ischemic stroke

This study evaluated the use of conventional therapy combined with puerarin on ischemic stroke. Eighty patients with ischemic stroke admitted to Tangshan Gongren Hospital from March 2014 to September 2015 were randomly divided into two groups. The control group was treated with conventional therapy. The observation group was treated with an additional puerarin injection of 400 mg/day. The patients in both groups were examined for clinical neurological signs and symptoms. The levels of biochemical markers as well as changes in hemorheology were measured after the intervention and compared among the groups. Our results indicate that the language expression was significantly better in the observation group after the intervention (p<0.05). Additionally, the aphasia quotient was higher (p<0.05), the neurological deficit score was lower (p<0.05), and the functional ability score was higher (p<0.05). The plasma S-100B and NSE levels were lower (p<0.05), the whole blood viscosity and plasma viscosity were lower (p<0.05), and the levels of corticotropin-releasing hormone, corticotropin, cortisol, adrenaline and norepinephrine were lower (p<0.05). Our findings led to the conclusion that the use of puerarin can effectively improve the language function, reduce neurological damage, reduce blood viscosity, reduce stress response and improve quality of life.

Sesamin prevents apoptosis and inflammation after experimental myocardial infarction by JNK and NF-κB pathways

Myocardial infarction is a devastating event, especially when reperfusion is not performed. The inflammatory response has been associated with the pathogenesis of left ventricular remodeling after myocardial infarction. This study focused on the anti-apoptotic and anti-inflammatory effects of sesamin on ligation of the left anterior descending artery in an experimental mouse model and the potential mechanism underlying the activation of JNK and NF-κB pathways. Mice with MI induced by surgical left anterior descending coronary artery ligation were treated with sesamin by gavage for 1 week. Results showed that after treatment with sesamin, MI-induced cardiac damage was alleviated significantly, indicated by the histopathological examination. The myocardial apoptosis in the border zone was dramatically reduced by sesamin, resulting from the altered expression of apoptosis factors. Moreover, treatment with sesamin also mitigated the inflammatory response, decreased expression of cytokines and the inactivation of NF-κB (nuclear factor κB) signaling. Sesamin decreased the levels of p-JNK protein, which in turn inactivated pro-apoptotic signaling events by restoring the balance between mitochondrial pro-apoptotic Bcl-2 and Bax proteins. Thus, our study suggests that sesamin could alleviate MI-induced cardiac dysfunction through decrease of myocardial apoptosis and inflammatory response.

Efficacy and safety of puerarin injection in curing acute ischemic stroke: A meta-analysis of randomized controlled trials

BACKGROUND

Previous studies indicated that the puerarin injection has been widely employed in China for the treatment of acute ischemic stroke. We aim to evaluate the efficacy and safety of the puerarin injection for the treatment of acute ischemic stroke.

METHODS

A systematic literature search was performed in PUBMED, EMBASE, SPRINGER LINK, Scopus, Cochrane Library, China National Knowledge Infrastructure (CNKI), VIP Journals Database, Wanfang database and the China Biological Medicine database before November 2016, randomized controlled clinical trials (RCTs) of puerarin injection treating acute ischemic stroke were included. In addition, we searched reference lists of relevant retrieved articles. Two authors extracted data independently. The effective rate, the neurologic deficit score, the blood rheology indexes, and fibrinogen were assessed and analyzed by the Review Manager 5.3 software. The continuous variables were expressed as MD with 95% CI and dichotomous data used RR or ORs. Adverse reactions related to the puerarin injection were also examined.

RESULTS

Thirty-five RCTs with a total of 3224 participants were identified in the meta-analysis. The combined results of 32 trials indicated that the puerarin injection was better than control drugs at the clinical effective rate (RR 1.22, 95% CI 1.17 to 1.28, P < 0.001) and 16 studies showed the neurological deficit was significantly improved (MD -3.69, 95% CI -4.67 to -2.71, P < 0.001); the hemorheology index and fibrinogen were much lower with the puerarin injection when compared with western conventional medicines (WCM) or other control drugs (the whole blood viscosity: MD -0.89, 95% CI -1.37 to -0.41, P < 0.001; the HCT: MD -0.04, 95% CI -0.06 to -0.02, P < 0.001; the fibrinogen: MD -0.64, 95% CI -0.96 to -0.31, P < 0.001). Eleven trials reported that the adverse reactions related to the puerarin injection included facial flushing, dizziness, vomiting, nausea, and other mild gastrointestinal discomfort and allergic reaction. No serious adverse drug reactions were reported.

CONCLUSIONS

Puerarin injection may be more effective and relatively safe in clinic for treating acute ischemic stroke. However, the current evidence is insufficient due to the poor methodological quality and lack of adequate safety data. Further RCTs are required to examine its efficacy.

Effect of puerarin on transcriptome of astrocyte during oxygen-glucose deprivation/reoxygenation injury

Stroke is a serious disease with complex pathomechanism and limited therapeutic effect in clinic. Our previous research has found obvious therapeutic effect of Puerarin (Pur) on stroke injury of rat. The aim of this study is to investigate the transcriptome changes of oxygen-glucose deprivation/reoxygenation (OGD/R)-injured astrocytes before and after the intervention of Pur. Cells activity and apoptosis detection indicated that the activity of OGD/R-injured astrocytes was improved, and the apoptosis was ameliorated by Pur. Affymetrix GeneChip Rat Genome 230 2.0 Array assays indicated that after intervention of Pur, mRNA expressions of 31 genes were up-regulated and 40 genes were down-regulated in OGD group, whereas mRNA expression of 36 genes were up-regulated, and 88 genes were down-regulated in OGD/R group. Pathway analysis indicated that the olfactory transduction pathway and the JAK (janus kinase) 2/STAT (signal transducer and activator of transcription) three pathways were down-regulated by Pur during OGD/R injury of astrocytes. These data indicated that Pur regulates transcriptome and expresses protective effect on astrocytes during OGD/R injury, and may be a potential therapeutic agent for the treatment of stroke.

Anti-Inflammatory Effects of Traditional Chinese Medicines against Ischemic Injury in In Vivo Models of Cerebral Ischemia

Inflammation plays a crucial role in the pathophysiology of acute ischemic stroke. In the ischemic cascade, resident microglia are rapidly activated in the brain parenchyma and subsequently trigger inflammatory mediator release, which facilitates leukocyte-endothelial cell interactions in inflammation. Activated leukocytes invade the endothelial cell junctions and destroy the blood-brain barrier integrity, leading to brain edema. Toll-like receptors (TLRs) stimulation in microglia/macrophages through the activation of intercellular signaling pathways secretes various proinflammatory cytokines and enzymes and then aggravates cerebral ischemic injury. The secreted cytokines activate the proinflammatory transcription factors, which subsequently regulate cytokine expression, leading to the amplification of the inflammatory response and exacerbation of the secondary brain injury. Traditional Chinese medicines (TCMs), including TCM-derived active compounds, Chinese herbs, and TCM formulations, exert neuroprotective effects against inflammatory responses by downregulating the following: ischemia-induced microglial activation, microglia/macrophage-mediated cytokine production, proinflammatory enzyme production, intercellular adhesion molecule-1, matrix metalloproteinases, TLR expression, and deleterious transcription factor activation. TCMs also aid in upregulating anti-inflammatory cytokine expression and neuroprotective transcription factor activation in the ischemic lesion in the inflammatory cascade during the acute phase of cerebral ischemia. Thus, TCMs exert potent anti-inflammatory properties in ischemic stroke and warrant further investigation.

The pharmacokinetic screening of multiple components of the Nao Mai Tong formula in rat plasma by liquid chromatography tandem mass spectrometry combined with pattern recognition method and its application to comparative pharmacokinetics

The Nao Mai Tong formula (NMT) is composed of Rhubarb, Ginseng, Ligusticum wallichii and Pueraria in a ratio of 3:3:2:2 (w/w) and is a well-known traditional Chinese prescription that has been clinically employed for treating ischemia cerebrovascular disease. The goal of this study was to investigate the pharmacokinetics of multiple components (chryohol-8-O-β-D-glucoyroide, physcion-8-O-β-D-glucopyranoside, aloe-emodin, rhein, emodin, chrysophanol, ginsenoside Rg₁, ginsenoside Rb₁, ginsenoside Rb_3, ginsenoside Rc, senkyunolide I, ligustilide puerarin, daidzein, 3'-methoxy puerarin) after the oral administration of the NMT formula in rats. A rapid and sensitive UHPLC-Quadrupole-Orbitrap-MS with a sequential positive and negative ionization mode was developed to determine the 15 absorbed ingredients. After extraction from blood, the analytes and internal standards were subjected to ultra-high performance liquid chromatography with Agela Venusil MPC₁₈ (2.1mm×100mm, 3μm, Agela, USA). The mobile phase consisted of methanol and ammonium acetate (3mmolL^-1) under gradient elution conditions. This validated method was successfully applied to a comparative pharmacokinetic study of fifteen components in rat plasma after oral administration of the NMT formula or single herb extracts to normal and stroke-afflicted rats. A principal component analysis (PCA) was utilized to evaluate the differences in the pharmacokinetic behavior (time-course) of the absorbed components of NMT, and the absorbed components were assigned to 3 separate clusters. A comparison of the body dynamics of each group indicated that cluster B (ginsenoside Rg₁, ginsenoside Rb₁, ginsenoside Rb_3, ginsenoside Rc) might be the most important constituents controlling the pharmacological effects of NMT. The comparative pharmacokinetic study showed that the different groups had different pharmacokinetic characteristics. The pharmacokinetics-based UHPLC Quadrupole-Orbitrap-MS using a full-scan mode combined with a pattern recognition approach can provide a reliable and suitable means of screening and identifying potentially bioactive components that contribute to the pharmacological effects of Traditional Chinese Medicine (TCM).

Isoflavones: Anti-Inflammatory Benefit and Possible Caveats

Inflammation, a biological response of body tissues to harmful stimuli, is also known to be involved in a host of diseases, such as obesity, atherosclerosis, rheumatoid arthritis, and even cancer. Isoflavones are a class of flavonoids that exhibit antioxidant, anticancer, antimicrobial, and anti-inflammatory properties. Increasing evidence has highlighted the potential for isoflavones to prevent the chronic diseases in which inflammation plays a key role, though the underlying mechanisms remain unclear. Recently, some studies have raised concerns about isoflavones induced negative effects like carcinogenesis, thymic involution, and immunosuppression. Therefore, this review aims to summarize the anti-inflammatory effects of isoflavones, unravel the underlying mechanisms, and present the potential health risks.

Pharmacokinetic profiles of the five isoflavonoids from Pueraria lobata roots in the CSF and plasma of rats

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine Radix Puerariae, the roots of Pueraria lobata (Wild.) Ohwi., has been widely used for the treatment of cardiovascular and cerebrovascular diseases in China for centuries. Isoflavonoids are believed the active components of this herb.

AIM OF THIS STUDY

The present study aims to investigate the brain penetration and pharmacokinetics of five active isoflavonoids in the ventricular CSF and plasma of rats after intravenous administration of a Pueraria isoflavonoids (PIF) extract, to better understand the active components of this herb for neuro-activities.

MATERIAL AND METHODS

Under anesthesia condition, SD rats (n=6) were successively suffered two surgeries for implanting cannulas at lateral ventricle and right jugular vein for brain microdialysis and blood collection, respectively. After recovery, the rats received intravenous dose of PIF at 80mg/kg and the concentrations of puerarin (PU), 3'-methoxypuerarin (MPU), 3'-hydroxypuerarin (HPU), daidzein (DA) and daidzein-8-C-apiosyl-(1-6)-glycoside (DAC) in the ventricular dialysate and plasma samples were determined using a ultra-fast liquid chromatography tandem mass spectrometry method.

RESULTS

Complete concentration versus time profiles of the five components in plasma and four components except for HPU in ventricular CSF were obtained. After dosing, the average C0 values of PU, MPU, DA, DAC and HPU in plasma were estimated 6.53, 13.72, 1.54, 15.84 and 86.07µg/mL, and PU, MPU, DA and DAC were rapidly penetrated to the brain and reached to their Cmax of 521.52, 415.00, 74.34 and 380.03ng/mL in CSF at about 0.5-0.8h, respectively. The elimination t1/2 of PU, DA and DAC in CSF and plasma were no significant difference, while the t1/2 of MPU in ventricular CSF was longer than that in plasma which may attributable to the different physiological environment of central and peripheral compartments. The brain penetration index (AUCCSF/AUCplasma) was found to be about 9.29, 7.25, 11.96, and 4.21% for PU, MPU, DA, and DAC respectively.

CONCLUSION

PU, MPU, DA, DAC can quickly penetrate to the brain through the blood brain barrier (BBB) and might be responsible for the neuro-pharmacological activities of P. lobata.

Phytochemicals in Ischemic Stroke

Stroke is the second foremost cause of mortality worldwide and a major cause of long-term disability. Due to changes in lifestyle and an aging population, the incidence of stroke continues to increase and stroke mortality predicted to exceed 12 % by the year 2030. However, the development of pharmacological treatments for stroke has failed to progress much in over 20 years since the introduction of the thrombolytic drug, recombinant tissue plasminogen activator. These alarming circumstances caused many research groups to search for alternative treatments in the form of neuroprotectants. Here, we consider the potential use of phytochemicals in the treatment of stroke. Their historical use in traditional medicine and their excellent safety profile make phytochemicals attractive for the development of therapeutics in human diseases. Emerging findings suggest that some phytochemicals have the ability to target multiple pathophysiological processes involved in stroke including oxidative stress, inflammation and apoptotic cell death. Furthermore, epidemiological studies suggest that the consumption of plant sources rich in phytochemicals may reduce stroke risk, and so reinforce the possibility of developing preventative or neuroprotectant therapies for stroke. In this review, we describe results of preclinical studies that demonstrate beneficial effects of phytochemicals in experimental models relevant to stroke pathogenesis, and we consider their possible mechanisms of action.

Calycosin inhibits oxidative stress-induced cardiomyocyte apoptosis via activating estrogen receptor-α/β

Oxidative stress-induced myocardial apoptosis is a key step in the pathogenesis of ischemic heart disease. Calycosin is a phytoestrogen extracted from Radix astragali. In this study, we examined the effects and mechanisms of calycosin on oxidative stress-induced myocardial apoptosis. Molecular docking showed that calycosin can couple into binding site of ERα and β. Pretreatment with calycosin increased the expression levels of ERα and β. In H9C2 cells, H2O2 reduced cell viability and induced apoptosis, however, calycosin diminished the effects of H2O2 in a dose-dependent manner. Pretreatment with ICI 182,780, an estrogen receptor inhibitor, negated the protective effect of calycosin against H2O2-induced apoptosis. In addition, Akt phosphorylation was upregulated by calycosin mono treatment and downregulated by co-treatment with calycosin and ICI 182,780. These data demonstrated that calycosin exhibits anti-apoptotic effects by activating ERα/β and enhancing Akt phosphorylation in cardiomyocytes.

Sesamin attenuates neurotoxicity in mouse model of ischemic brain stroke

Stroke is a severe neurological disorder characterized by the abrupt loss of blood circulation into the brain resulting into wide ranging brain and behavior abnormalities. The present study was designed to evaluate molecular mechanism by which sesamin (SES) induces neuroprotection in mouse model of ischemic stroke. The results of this study demonstrate that SES treatment (30 mg/kg bwt) significantly reduced infarction volume, lipid per-oxidation, cleaved-caspase-3 activation, and increased GSH activity following MCAO in adult male mouse. SES treatment also diminished iNOS and COX-2 protein expression, and significantly restored SOD activity and protein expression level in the ischemic cortex of the MCAO animals. Furthermore, SES treatment also significantly reduced inflammatory and oxidative stress markers including Iba1, Nox-2, Cox-2, peroxynitrite compared to placebo MCAO animals. Superoxide radical production, as studied by DHE staining method, was also significantly reduced in the ischemic cortex of SES treated compared to placebo MCAO animals. Likewise, downstream effects of superoxide free radicals i.e. MAPK/ERK and P38 activation was also significantly attenuated in SES treated compared to placebo MCAO animals. In conclusion, these results suggest that SES induces significant neuroprotection, by ameliorating many signaling pathways activated/deactivated following cerebral ischemia in adult mouse.

Melanogenesis inhibitory effect of aerial part of Pueraria thunbergiana in vitro and in vivo

Melanin is major factor that determines skin color as well as one of the defense systems that prevent the UV-induced damage. In case of abnormal concentration of melanin, skin diseases or problems occur such as albinism, leukoplakia, melasma, freckles, moles, and lentigo. With the lifespan of humans has been extended, importance of ‘life quality’ has been increased. White and clean skin is very important part of the satisfaction of appearance, especially for Asia women. The aim of this study was to find an anti-melanogenesis activity for which the aerial part of Pueraria thunbergiana can be utilized based on the increase in demands for cosmetics, particularly natural products. We demonstrated anti-pigmentation effects of aerial part of P. thunbergiana by measuring melanin content and through staining in the B16F10 melanoma cell line. The aerial part of P. thunbergiana decreased tyrosinase activity significantly in B16F10 cell cultures, while there is no direct effect on enzyme in cell-free conditions. To define the mechanisms, real-time PCR, western blot, glucosidase activity and antioxidant activity assay were implemented. As results, we demonstrated that aerial part of P. thunbergiana has anti-melanogenesis activity via two mechanisms. One is downgrading microphthalmia-associated transcription factor by activating Akt/GSK-3β. Consequently, transcription of tyrosinase and tyrosinase-related protein 1 is decreased. Another is interrupting maturation of tyrosinase through inhibiting α-glucosidase. Furthermore, aerial part of P. thunbergiana showed great efficacy on pigmentation in vivo. These results suggest that aerial part of P. thunbergiana can be used as an anti-melanogenic agent.

Herbal medicines for ischemic stroke: combating inflammation as therapeutic targets

Stroke is a debilitating disease for which limited therapeutic approaches are available currently. Thus, there is an urgent need for developing novel therapies for stroke. Astrocytes, endothelial cells and pericytes constitute a neurovascular network for metabolic requirement of neurons. During ischemic stroke, these cells contribute to post-ischemic inflammation at multiple stages of ischemic cascades. Upon ischemia onset, activated resident microglia and astrocytes, and infiltrated immune cells release multiple inflammation factors including cytokines, chemokines, enzymes, free radicals and other small molecules, not only inducing brain damage but affecting brain repair. Recent progress indicates that anti-inflammation is an important therapeutic strategy for stroke. Given a long history with direct experience in the treatment of human subjects, Traditional Chinese Medicine and its related natural compounds are recognized as important sources for drug discovery. Last decade, a great progress has been made to identify active compounds from herbal medicines with the properties of modulating post-ischemic inflammation for neuroprotection. Herein, we discuss the inflammatory pathway in early stage and secondary response to injured tissues after stroke from initial artery occlusion to brain repair, and review the active ingredients from natural products with anti-inflammation and neuroprotection effects as therapeutic agents for ischemic stroke. Further studies on the post-ischemic inflammatory mechanisms and corresponding drug candidates from herbal medicine may lead to the development of novel therapeutic strategies in stroke treatment.