Protection against hydrogen peroxide-induced injury by Z-ligustilide in PC12 cells

Z-Ligustilide: A Potential Therapeutic Agent for Atherosclerosis Complicating Cerebrovascular Disease

Atherosclerosis (AS) is one of the major catalysts of ischemic cerebrovascular disease, and the death and disease burden from AS and its cerebrovascular complications are increasing. Z-ligustilide (Z-LIG) is a key active ingredient in Angelica sinensis (Oliv.) Diels and Ligusticum chuanxiong Hort. In this paper, we first introduced LIG's physicochemical properties and pharmacokinetics. Then, we reviewed Z-LIG's intervention and therapeutic mechanisms on AS and its cerebrovascular complications. The mechanisms of Z-LIG intervention in AS include improving lipid metabolism, antioxidant and anti-inflammatory effects, protecting vascular endothelium, and inhibiting vascular endothelial fibrosis, pathological thickening, and plaque calcification. In ischemic cerebrovascular diseases complicated by AS, Z-LIG exerts practical neuroprotective effects in ischemic stroke (IS), transient ischemic attack (TIA), and vascular dementia (VaD) through anti-neuroinflammatory, anti-oxidation, anti-neuronal apoptosis, protection of the blood-brain barrier, promotion of mitochondrial division and angiogenesis, improvement of cholinergic activity, inhibition of astrocyte proliferation, and endoplasmic reticulum stress. This paper aims to provide a basis for subsequent studies of Z-LIG in the prevention and treatment of AS and its cerebrovascular complications and, thus, to promote the development of interventional drugs for AS.

Evaluation of acute, 28-day, 13-week repeated dose oral toxicity and genotoxicity of a herbal extract (HemoHIM G) from Angelica sinensis, Ligusticum chuanxiong, and Peaonia lactiflora

HemoHIM G is a functional food ingredient composed of a triple herbal combination of Angelica sinensis, Ligusticum chuanxiong, and Paeonia lactiflora, to improve impaired immune function. Considering the pharmacological benefits of its constituent herbal components, HemoHIM G is anticipated to have various health benefits; however, its toxicity has not been thoroughly evaluated. Here, we conducted a comprehensive study to assess the safety of HemoHIM G in terms of acute oral toxicity, 13-week repeat-dose toxicity, and genotoxicity. In the oral acute toxicity study, Sprague-Dawley rats were orally administered a single dose of HemoHIM G at 5000 mg/kg/day, the limit dose for the acute study. No abnormal findings or adverse effects were observed in this study, as confirmed by gross pathology. A 13-week repeated-dose toxicity study was conducted with HemoHIM G at doses of 1250, 2500, and 5000 mg/kg/day to examine the subchronic toxicity in both male and female rats after 28 days of dose-range finding study. No test substance-related clinical signs or mortality was observed at any of the tested doses. Gross pathology, hematology, blood chemistry, and histopathology were within normal ranges, further supporting the safety of HemoHIM G. Therefore, the NOAEL of HemoHIM G was considered to be at 5000 mg/kg/day for both sexes of rats. Bacterial reverse mutation tests, a chromosome aberration test in human peripheral blood lymphocytes, and a mouse micronuclei test were conducted to identify the potential genotoxicity of HemoHIM G. HemoHIM G is non-mutagenic and non-clastogenic. Collectively, these findings provide valuable evidence for the safe use of HemoHIM G as a functional food ingredient.

Ligustilide-loaded liposome ameliorates mitochondrial impairments and improves cognitive function via the PKA/AKAP1 signaling pathway in a mouse model of Alzheimer's disease

BACKGROUND

Oxidative stress is an early event in the development of Alzheimer's disease (AD) and maybe a pivotal point of interaction governing AD pathogenesis; oxidative stress contributes to metabolism imbalance, protein misfolding, neuroinflammation and apoptosis. Excess reactive oxygen species (ROS) are a major contributor to oxidative stress. As vital sources of ROS, mitochondria are also the primary targets of ROS attack. Seeking effective avenues to reduce oxidative stress has attracted increasing attention for AD intervention.

METHODS

We developed liposome-packaged Ligustilide (LIG) and investigated its effects on mitochondrial function and AD-like pathology in the APPswe/PS1dE9 (APP/PS1) mouse model of AD, and analyzed possible mechanisms.

RESULTS

We observed that LIG-loaded liposome (LIG-LPs) treatment reduced oxidative stress and β-amyloid (Aβ) deposition and mitigated cognitive impairment in APP/PS1 mice. LIG management alleviated the destruction of the inner structure in the hippocampal mitochondria and ameliorated the imbalance between mitochondrial fission and fusion in the APP/PS1 mouse brain. We showed that the decline in cAMP-dependent protein kinase A (PKA) and A-kinase anchor protein 1 for PKA (AKAP1) was associated with oxidative stress and AD-like pathology. We confirmed that LIG-mediated antioxidant properties and neuroprotection were involved in upregulating the PKA/AKAP1 signaling in APPswe cells in vitro.

CONCLUSION

Liposome packaging for LIG is relatively biosafe and can overcome the instability of LIG. LIG alleviates mitochondrial dysfunctions and cognitive impairment via the PKA/AKAP1 signaling pathway. Our results provide experimental evidence that LIG-LPs may be a promising agent for AD therapy.

Essential oil from Ligusticum chuanxiong Hort. Alleviates lipopolysaccharide-induced neuroinflammation: Integrating network pharmacology and molecular mechanism evaluation

ETHNOPHARMACOLOGICAL RELEVANCE

Chuanxiong, the rhizome of Ligusticum chuanxiong Hort., is an ancient herbal medicine that has gained extensive popularity in alleviating migraines with satisfying therapeutic effects in China. As the major bioactive component of Chuanxiong, the essential oil also exerts a marked impact on the treatment of migraine. It is widely recognized that neuroinflammation contributes to migraine. However, it remains unknown whether Chuanxiong essential oil has anti-neuroinflammatory activity.

AIM OF THE STUDY

To explore the anti-neuroinflammatory properties of Chuanxiong essential oil and its molecular mechanisms by network pharmacology analysis and in vitro experiments.

MATERIALS AND METHODS

Gas chromatography-mass spectrometry (GC-MS) was used to identify the chemical components of Chuanxiong essential oil. Public databases were used to predict possible targets, build the protein-protein interaction network (PPI), and perform Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Moreover, cytological experiments, nitric oxide assay, enzyme-link immunosorbent assay, western blotting, and immunofluorescence assay were adopted to prove the critical signaling pathway in lipopolysaccharide (LPS)-induced BV2 cells.

RESULTS

Thirty-six compounds were identified from Chuanxiong essential oil by GC-MS, and their corresponding putative targets were predicted. The network pharmacology study identified 232 candidate targets of Chuanxiong essential oil in anti-neuroinflammation. Furthermore, Chuanxiong essential oil was found to potentially affect the C-type lectin receptor, FoxO, and NF-κB signaling pathways according to the KEGG analysis. Experimentally, we verified that Chuanxiong essential oil could significantly reduce the overproduction of inflammatory mediators and pro-inflammatory factors via the NF-κB signaling pathway.

CONCLUSION

Chuanxiong essential oil alleviates neuroinflammation through the NF-κB signaling pathway, which provides a theoretical foundation for a better understanding of the clinical application of Chuanxiong essential oil in migraine treatment.

Neurotrophic Natural Products

Neurotrophins (NGF, BDNF, NT3, NT4) can decrease cell death, induce differentiation, as well as sustain the structure and function of neurons, which make them promising therapeutic agents for the treatment of neurodegenerative disorders. However, neurotrophins have not been very effective in clinical trials mostly because they cannot pass through the blood-brain barrier owing to being high-molecular-weight proteins. Thus, neurotrophin-mimic small molecules, which stimulate the synthesis of endogenous neurotrophins or enhance neurotrophic actions, may serve as promising alternatives to neurotrophins. Small-molecular-weight natural products, which have been used in dietary functional foods or in traditional medicines over the course of human history, have a great potential for the development of new therapeutic agents against neurodegenerative diseases such as Alzheimer's disease. In this contribution, a variety of natural products possessing neurotrophic properties such as neurogenesis, neurite outgrowth promotion (neuritogenesis), and neuroprotection are described, and a focus is made on the chemistry and biology of several neurotrophic natural products.

Klotho, Oxidative Stress, and Mitochondrial Damage in Kidney Disease

Reducing oxidative stress stands at the center of a prevention and control strategy for mitigating cellular senescence and aging. Kidney disease is characterized by a premature aging syndrome, and to find a modulator targeting against oxidative stress, mitochondrial dysfunction, and cellular senescence in kidney cells could be of great significance to prevent and control the progression of this disease. This review focuses on the pathogenic mechanisms related to the appearance of oxidative stress damage and mitochondrial dysfunction in kidney disease. In this scenario, the anti-aging Klotho protein plays a crucial role by modulating signaling pathways involving the manganese-containing superoxide dismutase (Mn-SOD) and the transcription factors FoxO and Nrf2, known antioxidant systems, and other known mitochondrial function regulators, such as mitochondrial uncoupling protein 1 (UCP1), B-cell lymphoma-2 (BCL-2), Wnt/β-catenin, peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1 alpha), transcription factor EB, (TFEB), and peroxisome proliferator-activated receptor gamma (PPAR-gamma). Therefore, Klotho is postulated as a very promising new target for future therapeutic strategies against oxidative stress, mitochondria abnormalities, and cellular senescence in kidney disease patients.

Multiple Mechanistic Action of Brevinin-1FL Peptide against Oxidative Stress Effects in an Acute Inflammatory Model of Carrageenan-Induced Damage

Amphibian skin is acknowledged to contain an antioxidant system composed of various gene-encoded antioxidant peptides, which exert significant effects on host defense. Nevertheless, recognition of such peptides is in its infancy so far. Here, we reported the antioxidant properties and underlying mechanism of a new antioxidant peptide, brevinin-1FL, identified from Fejervarya limnocharis frog skin. The cDNA sequence encoding brevinin-1FL was successfully cloned from the total cDNA of F. limnocharis and showed to contain 222 bp. The deduced mature peptide sequence of brevinin-1FL was FWERCSRWLLN. Functional analysis revealed that brevinin-1FL could concentration-dependently scavenge ABTS⁺, DPPH, NO, and hydroxyl radicals and alleviate iron oxidation. Besides, brevinin-1FL was found to show neuroprotective activity by reducing contents of MDA and ROS plus mitochondrial membrane potential, increasing endogenous antioxidant enzyme activity, and suppressing H₂O₂-induced death, apoptosis, and cycle arrest in PC12 cells which were associated with its regulation of AKT/MAPK/NF-κB signal pathways. Moreover, brevinin-1FL relieved paw edema, decreased the levels of TNF-α, IL-1β, IL-6, MPO, and malondialdehyde (MDA), and restored catalase (CAT) and superoxide dismutase (SOD) activity plus glutathione (GSH) contents in the mouse injected by carrageenan. Together, these findings indicate that brevinin-1FL as an antioxidant has potent therapeutic potential for the diseases induced by oxidative damage. Meanwhile, this study will help us further comprehend the biological functions of amphibian skin and the mechanism by which antioxidants protect cells from oxidative stress.

Effect of Zhenxin Xingshui Yizhi Fang on Aβ25-35 induced expression of related transporters in HBMEC cell model

ETHNOPHARMACOLOGICAL RELEVANCE

Aβ (β-amyloid) deposition and abnormal transport were suggested to be risk factors for Alzheimer's disease (AD). Zhenxin Xingshui Yizhi Fang (XSF), an ancient prescription in traditional Chinese medicine, was first recorded in Qianjin Yifang for treating palpitation, hypnosia, amnesia. It is reported that XSF could improve mice learning memory ability, reduce the deposition of senile plaques in hippocampus of rat brain. In this study, the neuroprotective effect of XSF against Aβ_25-35-induced apoptosis in cultured human brain microvascular endothelial cells (HBMEC) and its potential mechanism were investigated.

MATERIALS AND METHODS

HBMEC cells were treated with Aβ_25-35 to established neurotoxic cell model. After that, the cells were treated with 125, 250, 500 μg/mL XSF to observe the protective effect. The viability of HBMEC cells were evaluated by MTT assay, the Aβ_25-35-induced apoptosis was characterized by Hoechst-33258 and the activity of cysteinyl aspartate specific proteinase-3. The expression level of Aβ_1-42 in cells induced by Aβ_25-35 was measured by human Aβ_1-42 kit. Protein and mRNA expression levels of advanced glycation end products (RAGE), low density lipoprotein receptor-related protein 1 (LRP1), glucose transporter 1 and 3 (GLUT1 and GLUT3) were assayed by capillary electrophoresis immunoassay and quantitative real-time polymerase chain reaction analyses.

RESULTS

In Aβ_25-35 induced neurotoxic cells, the percentage of apoptotic cells, the concentration of Aβ_1-42 and CASPASE-3 activity, protein and mRNA expression levels of RAGE increased significantly, but that of LRP1, GLUT1 and GLUT3 significantly decreased. XSF could inhibit the apoptotic of cells, reduced the concentration of Aβ_1-42 and CASPASE-3 expression, downregulate RAGE and upregulate LRP1, GLUT1 and GLUT3 expression.

CONCLUSION

The results suggest that XSF can reduce the cytotoxicity of HBMEC induced by Aβ_25-35, inhibit apoptosis, and regulate the transport of Aβ on BBB and energy metabolism disorder in HBMEC.

Hydroxy-α-sanshool Possesses Protective Potentials on H2O2-Stimulated PC12 Cells by Suppression of Oxidative Stress-Induced Apoptosis through Regulation of PI3K/Akt Signal Pathway

Zanthoxylum bungeanum pericarp is a commonly used herbal medicine in China with effects of anti-inflammatory and analgesic, improving learning and memory ability, while hydroxy-α-sanshool (HAS) is the most important active ingredient of Z. bungeanum pericarps. The purpose of this study was to investigate the neuroprotective effect of HAS and its related possible mechanisms using a H₂O₂-stimulated PC12 cell model. CCK-8 assay results showed that HAS had a significant protective effect on H₂O₂-stimulated PC12 cells without obvious cytotoxicity on normal PC12 cells. Flow cytometry and fluorescence microscope (DAPI staining and DCFH-DA staining) indicated that HAS could reduce the H₂O₂-induced apoptosis in PC12 cells via reduction of intracellular ROS and increase of mitochondrial membrane potential (MMP). Subsequently, results of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) determination suggested that HAS could increase the enzyme activities of SOD, CAT, and GSH-Px whereas it could decrease the MDA contents in H₂O₂-stimulated PC12 cells. Furthermore, the western blotting assays showed that HAS could upregulate the expressions of p-PI3k, Akt, p-Akt, and Bcl-2, while it could downregulate the expressions of cleaved caspase-3 and Bax in H₂O₂-stimulated PC12 cells. Collectively, it could be concluded according to our results that HAS possesses protective potentials on H₂O₂-stimulated PC12 cells through suppression of oxidative stress-induced apoptosis via regulation of PI3K/Akt signal pathway.

Ligustilide Attenuates Ischemia Reperfusion-Induced Hippocampal Neuronal Apoptosis via Activating the PI3K/Akt Pathway

Ligustilide (LIG), a main lipophilic component isolated from Cnidii Rhizoma (Cnidium officinale, rhizome) and Angelicae Gigantis Radix (Angelica gigas Nakai, root), has been shown to alleviate cerebral ischemia injury and paly a neuroprotective role. We investigated mechanisms underlying the antiapoptotic effects of LIG in vitro and in vivo, respectively, using cultured primary hippocampal neurons under oxygen-glucose deprivation/reperfusion (OGD/R) and rats under cerebral ischemia reperfusion(I/R) conditions. In vitro studies revealed that the suppressed apoptosis in hippocampal neurons upon LIG treatment was associated with reduced calcium influx and generation of reactive oxygen species. The LIG-treated hippocampal neurons exhibited decreased the ratio of Bax/Bcl-2, and the release of CytC from mitochondria as well as the expression of cleaved caspase-3, which were accompanied with enhanced the phosphorylation of Akt protein, in a PI3K-dependent manner. In vivo studies demonstrated a neuroprotective role of LIG in attenuating cerebral infarction volume, neurological injury and hippocampal neuron injury, suggesting that LIG could reverse ischemia reperfusion(I/R)-induced apoptosis of hippocampal neurons. These results together suggest that LIG may be considered as a neuroprotectant in the treatment of ischemia stroke.

Structure-Activity Analysis and Molecular Docking Studies of Coumarins from Toddalia asiatica as Multifunctional Agents for Alzheimer's Disease

Coumarins, naturally occurring phytochemicals, display a wide spectrum of biological activities by acting on multiple targets. Herein, nine coumarins from the root of Toddalia asiatica were evaluated for activities related to pathogenesis of Alzheimer's disease (AD). They were examined for acetylcholinesterase (AChE) and AChE- or self-induced amyloid beta (Aβ) aggregation inhibitory activities, as well as neuroprotection against H₂O₂- and Aβ_1-42-induced human neuroblastoma SH-SY5Y cell damage. Moreover, in order to understand the mechanism, the binding interactions between coumarins and their targets: (i) AChE and (ii) Aβ_1-42 peptide were investigated in silico. All coumarins exhibited mild to moderate AChE and self-induced Aβ aggregation inhibitory actions. In addition, the coumarins substituted with the long alkyl chain at position 6 or 8 illustrated ability to inhibit AChE-induced Aβ aggregation, resulting from their dual binding site at catalytic anionic site and peripheral active site in AChE. Moreover, the most potent multifunctional coumarin, phellopterin, could attenuate neuronal cell damage induced by H₂O₂ and Aβ_1-42 toxicity. Conclusively, seven out of nine coumarins were identified as multifunctional agents inhibiting the pathogenesis of AD. The structure-activity relationship information obtained might be applied for further optimization of coumarins into a useful drug which may combat AD.

Theaflavins alleviate sevoflurane-induced neurocytotoxicity via Nrf2 signaling pathway

Aim: Sevoflurane could induce apoptosis of rat hippocampal neurons, while theaflavins (TFs) have antioxidant and anti-inflammatory properties. This study aims to explore whether TFs could alleviate sevoflurane-induced neuronal cell injury.Materials and methods: Cells were treated by concentration gradient of sevoflurane and TFs. Cell viability, level of reactive oxygen species (ROS) and apoptosis rate were determined by cell counting kit-8 (CCK-8) and flow cytometry, respectively. Quantitative PCR (qPCR) and western blot were performed to determine mRNA and protein expressions.Results: TFs promoted viability of cells under the treatment of sevoflurane, while it suppressed apoptosis and down-regulated ROS level in a concentration-dependent manner. TFs could also down-regulate expression levels of caspase-3 and caspase-9 and cytosol and intranuclear nuclear factor E2-related factor 2 (Nrf2) in rat hippocampal nerve cells, while it up-regulated those of heme oxygenase 1 (HO-1), NADPH quinine oxidoreductase 1 (NQO1), glutamate cysteine ligase (GCL) and peroxiredoxin 1 (Prx1).Conclusions: Our study suggests that TFs exert protective effects on sevoflurane-induced neurocytotoxicity and therefore could be used as a potential drug for treatment of neuronal injury.

Role of p38/MAPKs in Alzheimer's disease: implications for amyloid beta toxicity targeted therapy

A myriad of environmental and genetic factors, as well as the physiologic process of aging, contribute to Alzheimer's disease (AD) pathology. Neuroinflammation is and has been a focus of interest, as a common gateway for initiation of many of the underlying pathologies of AD. Amyloid beta (Aβ) toxicity, increasing RAGE expression, tau hyperphosphorylation, induction of apoptosis, and deregulated autophagy are among other mechanisms, partly entangled and being explained by activation of mitogen-activated protein kinase (MAPK) and MAPK signaling. p38 MAPK is the most essential regulator of Aβ induced toxicity from this family. p38 induces NF-κB activation, glutamate excitotoxicity, and disruption of synaptic plasticity, which are other implications of all justifying the p38 MAPK as a potential target to break the vicious Aβ toxicity cycle. Until recently, many in vivo and in vitro studies have investigated the effects of p38 MAPK inhibitors in AD. The pyridinyl imidazole compounds SB202190 and SB203580 have shown promising anti-apoptotic results in vivo. MW108 inhibits activation of p38 and is able to postpone cognitive decline in animal models. The PD169316, with anti-inflammatory, anti-oxidative, and anti-apoptotic features, has improved spatial memory in vivo. Natural compounds from Camellia sinensis (green tea), polyphenols from olive oil, pinocembrin from propolis, and the puerarine extract isoflavones, have shown strong anti-apoptotic features, mediated by p38 MAPK inhibition. Use of these drug targets is limited due to central nervous system side effects or cross-reactivity with other kinases, predicting the low efficacy of these drugs in clinical trials.

Sacculatane diterpenoids from the Chinese liverwort Pellia epiphylla with protection against H2O2-induced apoptosis of PC12 cells

Eight previously undescribed sacculatane diterpenoids, epiphyllins A-H, and one unknown bibenzyl-based isopentene along with seven known compounds were isolated from the Chinese liverwort Pellia epiphylla (L.) Corda. Their structures were established unequivocally on the basis of spectroscopic data and CD measurement. The quinine reductase-inducing activity evaluation demonstrated that epiphyllins A-D, 1β-hydroxysacculatanolide and pellianolactone B displayed moderate antioxidant effect. Further investigation of pellianolactone B revealed its protective effects on H₂O₂-induced oxidative insults and apoptosis in PC12 cells.

Ligustilide, a major bioactive component of Angelica sinensis, promotes bone formation via the GPR30/EGFR pathway

Angelica sinensis (Oliv.) Diels is a widely-used traditional Chinese herbal medicine in treating osteoporosis. Ligustilide (LIG) is the main component of A. sinensis and is considered to be the most effective biologically active ingredient in this plant. LIG has been found to have multiple pharmacological activities, such as anti-atherosclerosis, neuroprotection, anticancer, anti-inflammatory and analgesic. However, little is known regarding its anti-osteoporotic effects. The aims of this study were to investigate any protective effect of LIG on bone formation. The results showed that LIG significantly ameliorated inhibition of bone formation in zebrafish caused by prednisolone. LIG promoted osteoblast differentiation, including that of the pre-osteoblastic cell line MC3T3-E1 and bone marrow mesenchymal stem cells. LIG greatly improved the viability of MC3T3-E1 cells exposed to H₂O₂, attenuated H₂O₂-induced apoptosis and increased the expression of Bcl-2. Furthermore, LIG treatment lead to marked activation of phosphorylated EGFR and ERK1/2. These effects could be obviously inhibited by blocking GPR30 signaling with the specific inhibitor G15. Collectively, the results reveal that GPR30 is a positive switch for LIG to increase bone formation via regulation of EGFR, and these results provide evidence for the potential of LIG to treat osteoporosis.

Multiple Combination of Angelica gigas Extract and Mesenchymal Stem Cells Enhances Therapeutic Effect

Alternative medicines attract attention because stroke is rarely expected to make a full recovery with the most advanced medical technology. Angelica gigas (AG) is a well-known herbal medicine as a neuroprotective agent. The present study introduced mesenchymal stem cells (MSCs) to identify for the advanced treatment of the cerebrovascular disease. The objective of this research is validation of the enhanced effects of multiple combined treatment of AG extract with MSCs on stroke through angiogenesis. Our results confirmed that AG extract with MSCs improved the neovascularization increasing expression of angiogenesis-regulated molecules. The changes of brain and the behavioral ability showed the increased effects of AG extract with MSCs. As a result, AG extract and MSCs may synergistically increase the therapeutic potential by enhancing neovascularization. This mixed approach provides a new experimental protocol of herbal medicine therapy for the treatment of a variety of diseases including stroke, trauma, and spinal cord injury.

Cytoprotective Effects of Mangiferin and Z-Ligustilide in PAH-Exposed Human Airway Epithelium in Vitro

According to World Health Organisation (WHO) air pollution increases the risk of cardiovascular disorders, respiratory diseases, including COPD, lung cancer and acute respiratory infections, neuro-degenerative and other diseases. It is also known that various phytochemicals may mitigate such risks. This study tested if phytochemicals mangiferin (MNG) and Z-ligustilide (Z-LG) may protect PAH-exposed human lung bronchial epithelial cells (BEAS-2B). Organic PAH extract was obtained from the urban fine PM with high benzo(a)pyrene content collected in Eastern European mid-sized city during winter heating season. Cell proliferation traits and levels of intracellular oxidative stress were examined. Effect of MNG (0.5 µg/mL) alone or in combination with PAH on bronchial epithelium wound healing was evaluated. Both phytochemicals were also evaluated for their antioxidant properties in acellular system. Treatment with MNG produced strong cytoprotective effect on PAH-exposed cells (p < 0.01) while Z-LG (0.5 µg/mL) exhibited strong negative effect on cell proliferation in untreated and PAH-exposed cells (p < 0.001). MNG, being many times stronger antioxidant than Z-LG in chemical in vitro assays (p < 0.0001), was also able to decrease PAH-induced oxidative stress in the cell cultures (p < 0.05). Consequently MNG ameliorates oxidative stress, speeds up wound healing process and restores proliferation rate in PAH-exposed bronchial epithelium. Such protective effects of MNG in air pollution affected airway epithelium stimulate further research on this promising phytochemical.

Ligustilide Ameliorates Memory Deficiency in APP/PS1 Transgenic Mice via Restoring Mitochondrial Dysfunction

Ligustilide, the main lipophilic component of Radix angelicae sinensis, has been shown to ameliorate cognitive dysfunction in a few Alzheimer's disease mouse models, but its mechanism is not fully understood. In this study, we employed 7-month-old APP/PS1 mice to explore whether LIG is able to protect against Alzheimer's disease progression. The Morris water maze and Y-maze test results showed that eight weeks of intragastric administration of LIG (10 mg/kg, 40 mg/kg) every day improved memory deficit in APP/PS1 mice. The thioflavin-S staining and Western blot results (Aβ_1-42 monomer/oligomer, APP, ADAM10, SAPPα, and PreP) showed that LIG reduced Aβ levels in the brain of APP/PS1 mice. Transmission electron microscopy analysis showed that LIG reduced the mitochondria number and increased the mitochondrial length in the hippocampal CA1 area of APP/PS1 mice. A reduced level of Drp1 (fission) and increased levels of Mfn1, Mfn2, and Opa1 (fusion) were found in APP/PS1 mice treated with LIG. An increased ATP level in the brain and increased activities of cytochrome c oxidase (CCO) and succinate dehydrogenase (SDH) in mitochondrion separated from the hippocampus and cortex revealed that LIG alleviated mitochondrial dysfunction. LIG exerts an antioxidation effect via reducing the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) and increasing the activity of Mn-SOD in the brain. Elevated levels of PSD-95, synaptophysin, and synapsin 1 in both the hippocampus and cortex indicated that LIG provided synaptic protection. These findings show that treatment with LIG ameliorates mitochondrial dynamics and morphology issues, improves mitochondrial function, reduces Aβ levels in the brain, restores the synaptic structure, and ameliorates memory deficit in APP/PS1 mice. These results imply that LIG may serve as a potential antidementia drug.

Screening potential mitochondria-targeting compounds from traditional Chinese medicines using a mitochondria-based centrifugal ultrafiltration/liquid chromatography/mass spectrometry method

Mitochondria regulate numerous crucial cell processes, including energy production, apoptotic cell death, oxidative stress, calcium homeostasis and lipid metabolism. Here, we applied an efficient mitochondria-based centrifugal ultrafiltration/liquid chromatography/mass spectrometry (LC/MS) method, also known as screening method for mitochondria-targeted bioactive constituents (SM-MBC). This method allowed searching natural mitochondria-targeting compounds from traditional Chinese medicines (TCMs), including Puerariae Radix (PR) and Chuanxiong Radix (CR). A total of 23 active compounds were successfully discovered from the two TCMs extracts. Among these 23 hit compounds, 17 were identified by LC/MS, 12 of which were novel mitochondria-targeting compounds. Among these, 6 active compounds were analyzed in vitro for pharmacological tests and found able to affect mitochondrial functions. We also investigated the effects of the hit compounds on HepG2 cell proliferation and on loss of cardiomyocyte viability induced by hypoxia/reoxygenation injury. The results obtained are useful for in-depth understanding of mechanisms underlying TCMs therapeutic effects at mitochondria level and for developing novel potential drugs using TCMs as lead compounds. Finally, we showed that SM-MBC was an efficient protocol for the rapid screening of mitochondria-targeting constituents from complex samples such as PR and CR extracts.

Neuroprotective Effects of n-3 Polyunsaturated Fatty Acid-Enriched Phosphatidylserine Against Oxidative Damage in PC12 Cells

Neurodegenerative diseases are defined by progressive loss of specific neuronal cell populations and are associated with protein aggregates. Oxidative stress has been implicated in their pathological processes. Previous studies revealed that docosahexaenoic acid (DHA) is beneficial in neurodegenerative diseases. Phospholipids (PLs) derived from marine products are rich in DHA and eicosapentaenoic acid (EPA). In the present study, we investigated the neuroprotective effects of DHA-enriched and unenriched phosphatidylcholine (PC) and phosphatidylserine (PS) on oxidative stress induced by hydrogen peroxide (H2O2) and tert-butylhydroperoxide in PC12 cells. Cell viability and leakage of lactate dehydrogenase results showed that the neuroprotective effect of PS was superior to that of PC. DHA- and EPA-enriched PC and PS were superior to that without DHA or EPA; in addition, the improvement with n-3 polyunsaturated fatty acid-enriched PS (n-3 PS) was dose dependent. Acridine orange/ethidium bromide staining showed that DHA- and EPA-enriched PS (DHA/EPA-PS) could significantly inhibit apoptosis. Mechanistic studies revealed that EPA-PS and DHA-PS were effective to increase superoxide dismutase (SOD) levels by 48.4 and 58.2 % and total antioxidant capacity (T-AOC) level by 51 and 94 %, respectively, in the H2O2 model. Similar results for SOD and T-AOC levels were shown in the t-BHP model. EPA/DHA-PS could downregulate the messenger RNA level of Caspase-3, Caspase-9, and Bax, upregulate Bcl-2, inhibit Bax, and increase Bcl-2 at protein level. In conclusion, EPA/DHA-PS could protect PC12 cells from oxidative stress and prevent mitochondrial-mediated apoptosis. Our findings indicate that the neuroprotective effects of DHA/EPA-PLs depend on the molecular form. Further studies are necessary to reveal detailed mechanisms and structure-effect relationships.

The Japanese Angelica acutiloba root and yokukansan increase hippocampal acetylcholine level, prevent apoptosis and improve memory in a rat model of repeated cerebral ischemia

ETHNOPHARMACOLOGICAL RELEVANCE

Japanese Angelica acutiloba root (Angelica root) is included in several Kampo medicines including Yokukansan (YKS). Angelica root and YKS are used for the treatment of a variety of psychological and neurodegenerative disorders. Development of safe and effective therapeutic agents against cerebrovascular disorders will improve the treatment of patients with dementia.

AIM OF THE STUDY

The effect of Angelica root and YKS on ischemia-impaired memory has not yet been fully investigated. The present study investigated whether Angelica root is also involved in memory improving and neuroprotective effect of YKS in a model of cerebrovascular ischemia.

MATERIALS AND METHODS

Male Wistar rats grouped into sham rats received saline, and other three groups subjected to repeated cerebral ischemia induced by 4-vessel occlusion (4-VO), received a 7-day oral administration of either saline, Angelica root or YKS. Memory was evaluated by eight-arm radial maze task. Acetylcholine release (ACh) in the dorsal hippocampus was investigated by microdialysis-HPLC. Apoptosis was determined by terminal deoxynucleotidyl transferase (TdT)-mediated fluorescein-deoxyuridine triphosphate (dUTP) nick-end labeling.

RESULTS

Ischemia induced apoptosis, reduced release of ACh, and impaired the memory (increased error choices and decreased correct choices). Angelica root and YKS improved the memory deficits, upregulated the release of ACh and prevented 4-VO-induced hippocampal apoptosis.

CONCLUSION

The dual ACh-increasing and neuroprotective effect of Angelica root could make it a promising therapeutic agent useful for the treatment of symptoms of cerebrovascular dementia. Angelica root could be one of the components contributing to the memory-improving and neuroprotective effects of YKS.

Adipose-derived Stem Cells Stimulated with n-Butylidenephthalide Exhibit Therapeutic Effects in a Mouse Model of Parkinson's Disease

Parkinson's disease (PD) causes motor dysfunction and dopaminergic cell death. Drug treatments can effectively reduce symptoms but often cause unwanted side effects. Stem cell therapies using cell replacement or indirect beneficial secretomes have recently emerged as potential therapeutic strategies. Although various types of stem cells have been proposed as possible candidates, adipose-derived stem cells (ADSCs) are easily obtainable, more abundant, less ethically disputed, and able to differentiate into multiple cell lineages. However, treatment of PD using adult stem cells is known to be less efficacious than neuron or embryonic stem cell transplantation. Therefore, improved therapies are urgently needed. n-Butylidenephthalide (BP), which is extracted from Angelica sinensis, has been shown to have anti-inflammatory and neuroprotective effects. Indeed, we previously demonstrated that BP treatment of ADSCs enhances the expression of neurogenesis and homing factors such as nuclear receptor related 1 protein, stromal-derived factor 1, and brain-derived neurotrophic factor. In the present study, we examined the ability of BP-pretreated ADSC transplantation to improve PD motor symptoms and protect dopamine neurons in a mouse model of PD. We evaluated the results using neuronal behavior tests such as beam walking, rotarod, and locomotor activity tests. ADSCs with or without BP pretreatment were transplanted into the striatum. Our findings demonstrated that ADSC transplantation improved motor abilities with varied efficacies and that BP stimulation improved the therapeutic effects of transplantation. Dopaminergic cell numbers returned to normal in ADSC-transplanted mice after 22 d. In summary, stimulating ADSCs with BP improved PD recovery efficiency. Thus, our results provide important new strategies to improve stem cell therapies for neurodegenerative diseases in future studies.

Shikonin Protects PC12 Cells Against β-amyloid Peptide-Induced Cell Injury Through Antioxidant and Antiapoptotic Activities

Excessive accumulation of β-amyloid (Aβ) is thought to be a major causative factor in the pathogenesis of Alzheimer's disease (AD). Pretreating Aβ-induced neurotoxicity is a potential therapeutic approach to ameliorate the progression and development of AD. The present study aimed to investigate the neuroprotective effect of shikonin, a naphthoquinone pigment isolated from the roots of the traditional Chinese herb Lithospermum erythrorhizon, on Aβ1-42-treated neurotoxicity in PC12 cells. Pretreating cells with shikonin strongly improved cell viability, decreased the malondialdehyde and reactive oxygen species (ROS) content, and stabilized the mitochondrial membrane potential in Aβ1-42-induced PC12 cells. In addition, shikonin strongly improved the response of the antioxidant system to ROS by increasing the levels of superoxidedismutase, catalase and glutathione peroxidase. Furthermore, shikonin has the ability to reduce proapoptotic signaling by reducing the activity of caspase-3 and moderating the ratio of Bcl-2/Bax. These observations indicate that shikonin holds great potential for neuroprotection via inhibition of oxidative stress and cell apoptosis.

Blood-brain barrier permeability and neuroprotective effects of three main alkaloids from the fruits of Euodia rutaecarpa with MDCK-pHaMDR cell monolayer and PC12 cell line

The fruits of Euodia rutaecarpa (Euodiae Fructus, EF), the widely used traditional Chinese medicine, have various central nervous system effects. Alkaloids following as evodiamine (EDM), rutaecarpine (RCP) and dehydroevodiamine (DEDM) are the major substances in EF. The MDCK-pHaMDR cell monolayer model was utilized as a blood-brain barrier (BBB) surrogate model to study their BBB permeability. The transport samples were analyzed by high performance liquid chromatography and the apparent permeability coefficients (P_app) were calculated. EDM and RCP showed high permeability through BBB by passive diffusion, while DEDM showed moderate permeability with efflux mechanism related to P-glycoprotein (P-gp). EDM and RCP could also reduce the efflux of DEDM probably by inhibiting P-gp. The neuroprotective effects of the three alkaloids were then studied on the PC12 cell line injured by 1-methyl-4-phenylpyridinium ion (MPP⁺) or hydrogen peroxide (H₂O₂). EDM could significantly reduce MPP⁺ or H₂O₂-induced cell injury dose-dependently. RCP could increase the cell viability in MPP⁺ treated group while DEDM showed a protective effect against H₂O₂ injury. This study predicted the permeability of EDM, RCP and DEDM through BBB and discovered the neuroprotective substance basis of EF as a potential encephalopathy drug.

Potassium 2-(1-hydroxypentyl)-benzoate attenuates neuronal apoptosis in neuron-astrocyte co-culture system through neurotrophy and neuroinflammation pathway

Potassium 2-(1-hydroxypentyl)-benzoate (d,l-PHPB), a new drug candidate for ischemic stroke at the phase II clinic trial, has been shown to protect neurons by inhibiting oxidative injury and reducing neuron apoptosis in previous studies. But the mechanisms of d,l-PHPB remain to be studied. In this study, a neuron–astrocytes co-culture system was used to elucidate the roles of astrocytes in neuroprotection of d,l-PHPB under oxygen-glucose deprivation/reoxygenation (OGD/R) condition. Our data showed that d,l-PHPB reduced neuronal apoptosis in mono-culture system and this effect was enhanced in neuron–astrocyte co-culture system under the OGD/R condition. Meanwhile, d,l-PHPB obviously increased the levels of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), which were mainly secreted from astrocytes, in the co-culture system after OGD/R. The PI3K/AKT and ERK signaling pathways as well as the p-TRKA/B receptors were involved in the process. In addition, the levels of TNF-α and IL-1β secreted from astrocytes after OGD/R were markedly reduced after d,l-PHPB treatment, which was mainly due to the suppression of phosphorylated p38. In conclusion, the present study demonstrates that the neuroprotective effects of d,l-PHPB were improved by astrocytes, mainly mediated by increasing the release of BDNF/NGF and attenuating inflammatory cytokines.

Inhibitory effects of three bisbenzylisoquinoline alkaloids on lipopolysaccharide-induced microglial activation

Three bisbenzylisoquinoline alkaloids (liensinine, neferine, and isoliensinine) inhibit lipopolysaccharide-induced microglial activation.

Neuroprotective Effect of Ligustilide through Induction of α-Secretase Processing of Both APP and Klotho in a Mouse Model of Alzheimer's Disease

Emerging evidence suggests that alpha-processing single transmembrane proteins, amyloid precursor protein (APP) and anti-aging protein Klotho, are likely to be involved in the progression of Alzheimer's disease (AD). The natural phthalide Ligustilide (LIG) has been demonstrated to protect against aging- and amyloid-β (Aβ)-induced brain dysfunction in animal models. The present study is to investigate the effects of LIG on cognitive deficits and metabolism of both APP and Klotho and its underlying mechanism in AD double-transgenic (APP/PS1) mice and cultured human cells. Our results show that treatment with LIG significantly ameliorated memory impairment and Aβ levels and plaques burden. Specifically, LIG might act as a potent enhancer of α-secretase, disintegrin, and metalloprotease 10 (ADAM10), leading to upregulation of alpha-processing of both APP and Klotho and subsequent increases in the levels of both soluble APP fragment (sAPPα) and soluble Klotho (sKL) with inhibition of IGF-1/Akt/mTOR signaling in AD mice and cultured cells. Moreover, the specific ADAM10 inhibitor (G1254023X) effectively reversed LIG-induced alpha-processing of both APP and Klotho in vitro, while Klotho gene knockdown by small interfering RNA significantly blunted LIG-mediated inhibition of IGF-1/Akt/mTOR signaling in vitro. Taken together with the reported neuroprotective effects of both sAPPα and sKL as well as autophagy induction by Akt/mTOR pathway inhibition, our findings suggest that neuroprotection of LIG against AD is associated with induction alpha-processing of APP and Klotho and potential Aβ clearance. Whether LIG might induce Aβ autophagic clearance and the underlying mechanisms need to be further studied.

Natural products against Alzheimer's disease: Pharmaco-therapeutics and biotechnological interventions

Alzheimer's disease (AD) is a severe, chronic and progressive neurodegenerative disease associated with memory and cognition impairment ultimately leading to death. It is the commonest reason of dementia in elderly populations mostly affecting beyond the age of 65. The pathogenesis is indicated by accumulation of the amyloid-beta (Aβ) plaques and neurofibrillary tangles (NFT) in brain tissues and hyperphosphorylation of tau protein in neurons. The main cause is considered to be the formation of reactive oxygen species (ROS) due to oxidative stress. The current treatment provides only symptomatic relief by offering temporary palliative therapy which declines the rate of cognitive impairment associated with AD. Inhibition of the enzyme acetylcholinesterase (AChE) is considered as one of the major therapeutic strategies offering only symptomatic relief and moderate disease-modifying effect. Other non-cholinergic therapeutic approaches include antioxidant and vitamin therapy, stem cell therapy, hormonal therapy, use of antihypertensive or lipid-lowering medications and selective phosphodiesterase (PDE) inhibitors, inhibition of β-secretase and γ-secretase and Aβ aggregation, inhibition of tau hyperphosphorylation and intracellular NFT, use of nonsteroidal anti-inflammatory drugs (NSAIDs), transition metal chelators, insulin resistance drugs, etanercept, brain-derived neurotrophic factor (BDNF) etc. Medicinal plants have been reported for possible anti-AD activity in a number of preclinical and clinical trials. Ethnobotany, being popular in China and in the Far East and possibly less emphasized in Europe, plays a substantial role in the discovery of anti-AD agents from botanicals. Chinese Material Medica (CMM) involving Chinese medicinal plants has been used traditionally in China in the treatment of AD. Ayurveda has already provided numerous lead compounds in drug discovery and many of these are also undergoing clinical investigations. A number of medicinal plants either in their crude forms or as isolated compounds have exhibited to reduce the pathological features associated with AD. In this present review, an attempt has been made to elucidate the molecular mode of action of various plant extracts, phytochemicals and traditional herbal formulations investigated against AD as reported in various preclinical and clinical tests. Herbal synergism often found in polyherbal formulations were found effective to combat disease heterogeneity as found in complex pathogenesis of AD. Finally a note has been added to describe biotechnological improvement, genetic and genomic resources and mathematical and statistical techniques for empirical model building associated with anti-AD plant secondary metabolites and their source botanicals.

Locally and traditionally used Ligusticum species - A review of their phytochemistry, pharmacology and pharmacokinetics

ETHNOPHARMACOLOGICAL RELEVANCE

Ligusticum species (Umbelliferae) have been widely used in traditional Chinese medicine, Korean folk medicine and Native American medicine for their medicinal and nutritional value. Decoctions of the rhizomes are used in treatment and prophylaxis of migraine, anemia and cardiovascular conditions including stroke.

AIM OF STUDY

This review is intended to fully compile the constituents of locally and traditionally used Ligusticum species, present their bioactivities and highlight potential leads for future drug design, and thus, provide a reference for further research and application of these species. Emphasis is also placed on current trends in the pharmacokinetic studies of the major constituents.

METHODS

The literature discussed is derived from readily accessible papers spanning the early 1990s to the end of 2015. Information was collected from journals, books and online searches (Google Scholar, PubMed, ScienceDirect, SciFinder, Springerlink and CNKI).

RESULTS

The major phytoconstituents, 154 of which are presented in this review, include alkaloids, phthalides and phenolic acids. The crude extracts and isolated constituents have exhibited a wide range of in vitro and in vivo pharmacologic effects, including cardioprotective, antioxidant, anti-inflammatory and neuroprotective activities. The bioactive alkaloid tetramethylpyrazine (TMP) has attracted the most attention for its potent effect on calcium channels, anti-platelet as well as anti-inflammatory effects. Pharmacokinetic studies of major constituents have also been summarized.

CONCLUSION

The pthalides, organic acids and alkaloids of Ligusticum species have emerged as a good source of traditional medicines for the management of cardio- and cerebrovascular conditions, inflammation and neurogenerative disorders. The species discussed in this review have demonstrated wide pharmacological actions and have great potential to yield multipotent drugs if challenges such as poor bioavailability, solubility and toxicological profiles are addressed. Apart from the rhizomes, pharmacological activities of other botanical parts also need to be studied further. Expansion of research to cover other species in the Ligusticum genus would provide more opportunities for the discovery of new bioactive principles.

Neuroprotective effect of a novel Chinese herbal decoction on cultured neurons and cerebral ischemic rats

Background

Historically, traditional Chinese medicine has been widely used to treat stroke. Based on the theory of Chinese medicine and the modern pharmacological knowledge of herbal medicines, we have designed a neuroprotective formula called Post-Stroke Rehabilitation (PSR), comprising seven herbs – Astragalus membranaceus (Fisch.) Bunge, Salvia miltiorrhiza Bunge, Paeonia lactiflora Pall., Cassia obtusifolia L., Ligusticum chuanxiong Hort., Angelica sinensis (Oliv.) Diels, and Glycyrrhiza uralensis Fisch. We aim to examine the neuroprotective activity of PSR in vitro and in vivo, and to explore the underlying molecular mechanisms, to better understand its therapeutic effect and to further optimize its efficacy.

Methods

PSR extract or vehicle was applied to primary rat neurons to examine their survival effects against N-methyl-d-aspartate (NMDA)-elicited excitotoxicity. Whole-cell patch-clamp recording was conducted to examine the NMDA-induced current in the presence of PSR. ERK- and CREB-activation were revealed by western blot analysis. Furthermore, PSR was tested for CRE promoter activation in neurons transfected with a luciferase reporter. The protective effect of PSR was then studied in the rat middle cerebral artery occlusion (MCAO) model. MCAO rats were either treated with PSR extract or vehicle, and their neurobehavioral deficit and cerebral infarct were evaluated. Statistical differences were analyzed by ANOVA or t-test.

Results

PSR prominently reduced the death of cultured neurons caused by NMDA excitotoxicity in a dose-dependent manner, indicating its neuroprotective property. Furthermore, PSR significantly reduced NMDA-evoked current reversibly and activated phosphorylation of ERK and CREB with distinct time courses, with the latter’s kinetics slower. PSR also triggered CRE-promoter activity as revealed by the increased expression of luciferase reporter in transfected neurons. PSR effectively reduced cerebral infarct and deficit in neurological behavior in MCAO rats when PSR decoction was administered starting either 6 days before or 6 h after onset of ischemia.

Conclusions

PSR is neuroprotective both in vitro and in vivo – it protects cultured neurons against NMDA excitotoxicity, and effectively reduces ischemic injury and neurobehavioral deficit in MCAO rats in both the pre- and post-treatment regimens. The underlying neuroprotective mechanisms may involve inhibition of NMDA receptor current and activation of ERK and CREB. This study provides important preclinical data necessary for the further development of PSR for stroke treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-016-1417-1) contains supplementary material, which is available to authorized users.

Chemical Compositions of Ligusticum chuanxiong Oil and Lemongrass Oil and Their Joint Action against Aphis citricola Van Der Goot (Hemiptera: Aphididae)

In order to develop novel botanical insecticides, the joint action of Ligusticum chuanxiong oil (LCO) and lemongrass oil (LO) against Aphis citricola van der Goot was determined systematically indoors and outdoors. The chemical profiles of LCO and LO as determined by gas chromatography-mass spectrometry (GC-MS) analysis revealed that the main compounds from LCO were (Z)-ligustilide (44.58%) and senkyunolide A (26.92%), and that of LO were geranial (42.16%) and neral (32.58%), respectively. The mixture of LCO and LO showed significant synergy against A. citricola, with a common-toxicity coefficient (CTC) value of 221.46 at the optimal ratio of LCO to LO (4:1, w:w). Based on the results of solvents and emulsifiers screening, L. chuanxiong oil·Lemongrass oil 20% emulsifiable concentrate (20% LCO·LO EC) was developed, and its stability was confirmed with tests of cold and thermal storage. Field trials indicated that the insecticidal activity of the diluted 20% LCO·LO EC (1000 fold dilution) was comparable to conventional pesticide (20% imidacloprid EC) on A. citricola seven days after application. Thus, the mixture of LCO and LO has the potential to be further developed as a botanical pesticide.

Neuroprotective Effects of Theaflavins Against Oxidative Stress-Induced Apoptosis in PC12 Cells

Oxidative stress can induce neuronal apoptosis via the production of superoxide and hydroxyl radicals. This process is as a major pathogenic mechanism in neurodegenerative disorders. In this study, we aimed to clarify whether theaflavins protect PC12 cells from oxidative stress damage induced by H₂O₂. A cell model of PC12 cells undergoing oxidative stress was created by exposing cells to 200 μM H₂O₂ in the presence or absence of varying concentrations of theaflavins (5, 10, and 20 μM). Cell viability was monitored using the MTT assay and Hoechst 33258 staining, showing that 10 μM theaflavins enhanced cell survival following 200 μM H₂O₂ induced toxicity and increased cell viability by approximately 40 %. Additionally, we measured levels of intracellular reactive oxygen species (ROS) and antioxidant enzyme activity. This suggested that the neuroprotective effect of theaflavins against oxidative stress in PC12 cells is derived from suppression of oxidant enzyme activity. Furthermore, Western blot analyses indicated that theaflavins downregulated the ratio of pro-apoptosis/anti-apoptosis proteins Bax/Bcl-2. Theaflavins also downregulated the expression of caspase-3 compared with a H₂O₂-treated group that had not been treated with theaflavins. Interestingly, this is the first study to report that the four main components of theaflavins found in black tea can protect neural cells (PC12) from apoptosis induced by H₂O₂. These findings provide the foundations for a new field of using theaflavins or its source, black tea, in the treatment of neurodegenerative diseases caused by oxidative stress.

Protection against β-amyloid-induced neurotoxicity by naturally occurring Z-ligustilide through the concurrent regulation of p38 and PI3-K/Akt pathways

Alzheimer's disease (AD) is primarily characterized by the progressive loss of functional neurons in the brain. Therefore, compounds with neuroprotective property may have therapeutic value in treating AD. Z-ligustilide (Z-LIG) is an essential oil originally isolated from umbelliferous plants. In the current study, the neuroprotective effects and underlying mechanisms of Z-LIG against fibrillar aggregates of Aβ_25-35 and Aβ_1-42-induced neurotoxicity were investigated in both SH-SY5Y cells and differentiated PC12 cells. Z-LIG at 1-30 μM provided an effective neuroprotection, as evidenced by the increase in cell viability, as well as the decrease in LDH release and intracellular accumulation of reactive oxygen species. Additionally, Z-LIG markedly blocked Aβ fibrils-induced condensed nuclei and sub-G1 accumulation suggestive of apoptosis. Furthermore, Z-LIG substantially reversed the activation of phosphorylated p38 and the inhibition of phosphorylated Akt caused by Aβ_25-35. LY294002, the specific inhibitor of PI3-K, significantly abrogated the protein expression of up-regulated phosphorylated Akt offered by Z-LIG. Most importantly, siRNA-mediated knockdown of PI3-K and p38 significantly abolished the neuroprotective effects of Z-LIG. The results taken together indicate that Z-LIG protects against Aβ fibrils-induced neurotoxicity possibly through the inhibition of p38 and activation of PI3-K/Akt signaling pathways concurrently. Z-LIG might be a potential candidate for further preclinical study aimed at the prevention and treatment of AD.

Protective Effects of Costunolide against Hydrogen Peroxide-Induced Injury in PC12 Cells

Oxidative stress-mediated cellular injury has been considered as a major cause of neurodegenerative diseases including Alzheimer’s and Parkinson’s diseases. The scavenging of reactive oxygen species (ROS) mediated by antioxidants may be a potential strategy for retarding the diseases’ progression. Costunolide (CS) is a well-known sesquiterpene lactone, used as a popular herbal remedy, which possesses anti-inflammatory and antioxidant activity. This study aimed to investigate the protective role of CS against the cytotoxicity induced by hydrogen peroxide (H₂O₂) and to elucidate potential protective mechanisms in PC12 cells. The results showed that the treatment of PC12 cells with CS prior to H₂O₂ exposure effectively increased the cell viability. Furthermore, it decreased the intracellular ROS, stabilized the mitochondria membrane potential (MMP), and reduced apoptosis-related protein such as caspase 3. In addition, CS treatment attenuated the cell injury by H₂O₂ through the inhibition of phosphorylation of p38 and the extracellular signal-regulated kinase (ERK). These results demonstrated that CS is promising as a potential therapeutic candidate for neurodegenerative diseases resulting from oxidative damage and further research on this topic should be encouraged.

Antihypertensive and antioxidant effects of hydroalcoholic extract from the aerial parts of Kelussia odoratissima Mozaff. in dexamethasone-induced hypertensive rats

Background:

Kelussia odoratissima Mozaff. is a monotypic endemic plant of Apiaceae growing wild in Iran. The aerial parts of this plant are used for treatment of hypertension, ulcer, and inflammatory conditions in folk medicine. In this study, the effects of hydroalcoholic extract of the aerial parts of K. odoratissima were evaluated in dexamethasone (Dex)-induced hypertension in male Wistar rats.

Materials and Methods:

For induction of hypertension, Dex (30 μg/kg/day) was administered subcutaneously for 14 days. In a prevention study, rats received oral K. odoratissima extract (100, 200, and 400 mg/kg) from 4 days before Dex administration and during the test period (days 1–18). In a reversal study, K. odoratissima extract was administered orally from day 8 to 14. Systolic blood pressure (SBP) was evaluated using tail-cuff method. The hydrogen peroxide (H₂O₂) concentration and ferric-reducing antioxidant power (FRAP) were measured in plasma samples.

Results:

Administrations of Dex significantly induced an increase in SBP and in plasma H₂O₂ and a decrease in body and thymus weights, and in FRAP value (P < 0.001). K. odoratissima extract dose-dependently prevented and reversed hypertension (P < 0.001). It also prevented and reduced the plasma H₂O₂ concentration and prevented the body weight loss upon Dex administration at all doses (100–400 mg/kg, P < 0.001) but failed to improve FRAP value.

Conclusions:

These results suggest antihypertensive and antioxidant effects of K. odoratissima extract in Dex-induced hypertension. Further studies are needed to elucidate the exact mechanism of the antihypertensive effect of this herbal medicine.

Effects of ferulic acid on antioxidant activity in Angelicae Sinensis Radix, Chuanxiong Rhizoma, and their combination

The present study aimed at exploring different roles of the same compound in different environment, using preparative HPLC, and the significance to investigating bio-active constituents in traditional Chinese medicine (TCM) on the basis of holism. In this study, the depletion of target component ferulic acid (FA) by using preparative HPLC followed by antioxidant activity testing was applied to investigate the roles of FA in Angelicae Sinensis Radix (DG), Chuanxiong Rhizoma (CX) and their combination (GX). The antioxidant activity was performed by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity testing. FA was successfully and exclusively depleted from DG, CX, and GX, respectively. By comparing the effects of the samples, it was found that FA was one of the main antioxidant constituents in DG, CX and GX, and the roles of FA were DG > CX > GX. Furthermore, the effects of FA varied at different doses in these herbs. This study provided a reliable and effective approach to clarifying the contribution of same compound in different TCMs to their bio-activities. The role of a constituent in different TCMs might be different, and a component with the same content might have different effects in different chemical environments. Furthermore, this study also suggested the potential utilization of preparative HPLC in the characterization of the roles of multi-ingredients in TCM.

A systems pharmacology approach to decipher the mechanism of danggui-shaoyao-san decoction for the treatment of neurodegenerative diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Neurodegenerative diseases (NDs) is a time-dependent course for a sequence of conditions that primarily impact the neurons in the human brain, ultimately, resulting in persistence and progressive degeneration and / or death of nerve cells and reduction of cognition and memory function. Currently, there are no therapeutic approaches to cure neurodegeneration, except certain medicines that temporarily alleviate symptoms, facilitating the improvement of a patients' quality of life. Danggui-shaoyao-san (DSS), as a famous Chinese herbal formula, has been widely used in the treatment of various illnesses, including neurodegenerative diseases. Although well-practiced in clinical medicine, the mechanisms involved in DSS for the treatment of neurodegenerative diseases remain elusive.

MATERIALS AND METHODS

In the present study, a novel systems pharmacology approach was developed to decipher the potential mechanism between DSS and neurodegenerative disorders, implicated in oral bioavailability screening, drug-likeness assessment, target identification and network analysis.

RESULTS

Based on a comprehensive systems approach, active compounds of DSS, relevant potential targets and targets associated with diseases were predicted. Active compounds, targets and diseases were used to construct biological networks, such as, compound-target interactions and target-disease networks, to decipher the mechanisms of DSS to address NDs.

CONCLUSIONS

Overall, a well-understood picture of DSS, hallmarked by multiple herbs-compounds-targets-pathway-cooperation networks for the treatment of NDs, was revealed. Notably, this systems pharmacology approach provided a novel in silico approach for the development paradigm of traditional Chinese medicine (TCM) and the generation of new strategies for the management of NDs.

Therapeutic Effect of Ligustilide-Stimulated Adipose-Derived Stem Cells in a Mouse Thromboembolic Stroke Model

Stroke is a result of cerebral ischemia that triggers a cascade of both physiological and biochemical events. No effective treatment is available for stroke; however, stem cells have the potential to rescue tissue from the effects of stroke. Adipose-derived stem cells (ADSCs) are an abundant source of adult stem cells; therefore, ADSC therapy can be considered as a future strategy for regenerative medicine. However, more research is required to improve the effectiveness of transplanted ADSCs as a treatment for stroke in the mouse stroke model. Ligustilide, isolated from the herb Angelica sinensis, exhibits a protective effect on neurons and inhibits inflammation. We also demonstrated that ligustilide treatment increases the expression levels of homing factors such as SDF-1 and CXCR4. In the present study, we evaluated the therapeutic effects of ADSC transplantation and ligustilide treatment in a mouse thromboembolic stroke model by behavioral tests, including beam walking, locomotor activity, and rotarod analysis. ADSCs pretreated with ligustilide were transplanted into the brains of stroke mice. The results showed that the therapeutic effect of ADSCs pretreated with ligustilide was better than that of ADSCs without ligustilide pretreatment. There was no difference between the recovery of mice treated by ADSC transplantation combined with subcutaneous ligustilide injection and that of mice treated only with ADSCs. The TUNEL assay showed fewer apoptotic cells in the brains of mice transplanted with ADSCs pretreated with ligustilide as well as in those without pretreatment. In summary, pretreatment of ADSCs with ligustilide improves the therapeutic efficacy of ADSC transplantation. The results of this study will help improve stem cell therapies being developed for future clinical applications.

Schisandrin B protects PC12 cells against oxidative stress of neurodegenerative diseases

Increasing evidence places Schisandrin B (Sch B) at an important position in nerve protection, indicating that Sch B might play a positive role in the therapy of neurodegenerative diseases. However, there is little information on it. Our studies showed that pretreatment with Sch B could reduce lactate dehydrogenase, malondialdehyde, and reactive oxygen species release and significantly increase the cell viability and the superoxide dismutase level. Sch B (10 μM) markedly inhibited cell apoptosis, whereas LY294002 (20 μM), a phosphatidylinositol-3 kinase inhibitor, blocked the antiapoptotic effect. More importantly, Sch B (10 μM) increased the phosphoprotein kinase B/protein kinase B (Akt) and B-cell lymphoma-2/Bcl-2 associated X protein ratios on preincubation with cells for 2 h, which was then inhibited by LY294002 (20 μM). Results indicate that Sch B can protect PC12 cells from apoptosis by activating the phosphatidylinositol-3 kinase/Akt signaling pathway and may emerge as a potential drug for neurodegenerative diseases.

Cocktail of Four Active Components Derived from Sheng Mai San Inhibits Hydrogen Peroxide-Induced PC12 Cell Apoptosis Linked with the Caspase-3/ROCK1/MLC Pathway

SMXZF, a combination of four active components including ginsenoside Rb1, ginsenoside Rg1, schizandrin, and DT-13 (6:9:5:4) that is derived from Sheng Mai San, has previously been shown to exhibit a neuroprotective effect against focal ischemia/reperfusion injury. Due to the key role of oxidative stress-induced neuronal apoptosis in the pathogenesis of stroke, we examined the effect of SMXZF in oxidative stress responses and related signaling pathways in differentiated pheochromocytoma (PC12) cells. Our results showed that incubation with 100 μM hydrogen peroxide (H2O2) for 12 hr could reduce cell viability and superoxide dismutase (SOD) activity with an increase of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA). In contrast, SMXZF alleviated oxidative stress by reducing the over-production of ROS and MDA in parallel to concentration dependently increasing SOD activity. In addition, SMXZF significantly attenuated H2O2-induced caspase-3 cleavage, Rho-associated coiled-coil-containing protein kinase-1 (ROCK1) activation, and myosin light-chain (MLC) phosphorylation. Inhibiting either caspase-3 or ROCK1 mimicked the effect. Consequently, our results suggest that SMXZF inhibits H2O2-induced neuronal apoptosis linked with the caspase-3/ROCK1/MLC pathway, which has also been confirmed to be a positive feedback loop in oxidative stress-injured PC12 cells. These findings support the pharmacological potential of SMXZF for neurodegenerative diseases and stroke.

Protective HSP70 Induction by Z-Ligustilide against Oxygen-Glucose Deprivation Injury via Activation of the MAPK Pathway but Not of HSF1

Heat-shock protein 70 (HSP70) is known to function as a protective molecular chaperone that is massively induced in response to misfolded proteins following cerebral ischemia. The objective of this study was to characterize HSP70 induction by Z-ligustilide and explore its potential role in protection against cerebral ischemia-reperfusion injury. Our results demonstrated that the intranasal administration of Z-ligustilide reduced infarct volume and improved neurological function in a rat stroke model. Meanwhile, Z-ligustilide enhanced the cell viability of PC12 cells insulted by oxygen-glucose deprivation-reoxygenation (OGD-Reoxy) and decreased apoptotic and necrotic cell death. Importantly, Z-ligustilide induced HSP70 expression both in vitro and in vivo. Although heat-shock factor 1 (HSF1) nuclear translocation was promoted by Z-ligustilide, HSP70-based heat-shock element (HSE)-binding luciferase activity was not activated, and HSP70 expression responsive to Z-ligustilide was not attenuated by HSE decoy oligonucleotides. However, Z-ligustilide significantly activated the phosphorylation of mitogen-activated protein kinases (MAPKs). Further inhibition of MAPK activity by specific inhibitors attenuated HSP70 induction by Z-ligustilide. Meanwhile, downregulation of HSP70 using KNK437, an HSP70 synthesis inhibitor, or small hairpin RNA (shRNA) significantly attenuated the protection of Z-ligustilide against OGD-Reoxy-induced injury. Moreover, the application of specific inhibitors of MAPKs also achieved similar results. Finally, Z-ligustilide alleviated the accumulation of ubiquitinated proteins induced by OGD-Reoxy, which was inhibited by HSP70-shRNA. Taken together, our results demonstrated that Z-ligustilide may induce protective HSP70 expression via the activation of the MAPK pathway, but not canonical HSF1 transcription. HSP70 plays a key role in the protection of Z-ligustilide against OGD-Reoxy-induced injury.

Pennogenyl saponins induce cell cycle arrest and apoptosis in human hepatocellular carcinoma HepG2 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Pennogenyl saponins, the characterized components of Rhizoma Paridis, have been reported to have anticancer activity through induction of apoptosis or anti-metastasis in cultured cells or animal models. The aim of the study was to evaluate the anticancer properties of four pennogenyl saponins (PS1-PS4) on a panel of human cancer and normal cell lines, and explore the potential mechanisms underlying the selective anticancer effects of the steroidal saponins in cancer cells.

MATERIALS AND METHODS

Differences in the anticancer activity of pennogenyl saponins were examined by MTT assay in human cancer cell lines (HepG2 hepatocellular carcinoma cells, UACC-257 melanoma cells, MCF-7 breast and PC-3 prostate cancer cells) and normal human cell lines (L-02 liver cells and HEK293 kidney cells). Flow cytometry analysis, JC-1 staining and western blot analysis were applied to detect the effects of anticancer pennogenyl saponins on apoptosis, cell cycle, and expression and/or activation of main effectors involved in the potential signaling pathways.

RESULTS

Among the tested four saponins, only PS1 and PS2 selectively inhibited cell growth in HepG2, MCF-7 and PC-3 cells. Moreover, PS1 and PS2 could significantly induce apoptosis and cell cycle G2/M arrest in HepG2 cells, which were at least associated with activation of mitochondrial caspase-dependent and -independent apoptotic cascades, inhibition of cyclin-dependent kinase 1 and PI3K/Akt signaling pathway, and modulation of mitogen-activated protein kinases.

CONCLUSIONS

PS1 and PS2 had potent and selective anticancer activity to breast, liver and prostate cancer cells. Furthermore, the anticancer effects of PS1 and PS2 were associated with induction of apoptosis and blockage of cell cycle progression through multiple targets in HepG2 cells. These findings suggest that PS1 and PS2 can be considered as potential agents for the treatment of some cancers such as hepatoma.