Astragaloside IV Synergizes with Ferulic Acid to Alleviate Hepatic Fibrosis in Bile Duct-Ligated Cirrhotic Rats.

BACKGROUND: Due to the multi-factorial etiology of hepatic fibrosis, multi-target therapeutics based on combinatory drugs is known to be a promising strategy for the disease. AIMS: The present study attempted to test the hypothesis that astragaloside IV combined with ferulic acid synergistically inhibits activation of hepatic stellate cells in vivo. METHODS: Bile duct-ligated rats were treated with astragaloside IV or/and ferulic acid for 28 days. Liver fibrosis was measured by histological examination. The oxidative stress-related biomarkers were measured with spectrophotometry. Expressions of mRNA and protein were measured by real-time PCR and Western blotting. RESULTS: Bile duct-ligated rat treatment with astragaloside IV and ferulic acid in combination resulted in synergistic alleviation of hepatic fibrosis. Simultaneously, activation of hepatic stellate cells was significantly inhibited by the combination therapy when compared with astragaloside IV or ferulic acid alone. Interestingly, astragaloside IV, but not ferulic acid, induced accumulation of Nrf2 in the nucleus, synthesized antioxidant enzymes through negative regulation of glycogen synthase kinase-3ß, scavenged reactive oxygen species, and, in turn, suppressed hepatic stellate cells activation in bile duct-ligated rats. Conversely, ferulic acid, but not astragaloside IV, suppressed TGF-ß1 and its receptors expression, which resulted in downregulation of Smad3 and Smad4. CONCLUSIONS: These findings suggest that the combination of astragaloside IV and ferulic acid synergistically induces deactivation of hepatic stellate cells through inhibition of the TGF-ß pathway and activation of the Nrf2 pathway, and suggest that combination of astragaloside IV and ferulic acid is a promising candidate for the treatment of hepatic fibrosis.

[Effect of maternal exposure to Curcumae Rhizoma during pregnancy on neurodevelopment and apoptosis mechanism in offspring].

Curcumae Rhizoma is a Chinese medicinal herb that is contraindicated during pregnancy. Cold-congelation and blood-stasis are corresponding syndromes to Curcumae Rhizoma. Whether syndrome-based treatment is associated with developmental neurotoxicity of Curcumae Rhizoma remains to be unclear. To verify the theory of traditional Chinese medicine of "syndrome-based treatment during pregnancy", the present study induced the mice blood stasis model by immersing mice in ice water. Pregnant C57 BL/6 wild type(WT) mice and pregnant Nrf2 knock out(KO) mice were randomly divided into control groups and Rhizoma Curcumae exposure groups. The mice were exposed to Rhizoma Curcumae during day 5 to day 18 after pregnancy. The neurodevelopment was examined to evaluate the differences of developmental neurotoxicity between normal and blood-stasis pregnant mice exposed to Rhizoma Curcumae. caspase-3 and caspase-9 activity in brain of the offspring were measured by colorimetric assays. Bcl-2 mRNA and protein expression in brain of the offspring were examined by Real-time RT-PCR and Western blot, respectively. According to the findings, C57 BL/6 mice exposed to Rhizoma Curcumae(10.0 g·kg~(-1)) had a longer positive occurring time of the surface righting reflex test of offspring and higher caspase-3 and caspase-9 activities in brain of offspring, compared with the normal control group, but with no significant change in those of blood-stasis pregnant mice offspring. However, mice exposed to Rhizoma Curcumae(10.0 g·kg~(-1)) showed no change in Bcl-2 gene expression and p38 MAPK phosphorylation in brain of the offspring. Nrf2 gene knockout using CRISPR/Cas9 resulted in a longer positive occurring time of the surface righting reflex test of offspring and higher caspase-3 and caspase-9 activities in brain of offspring. In conclusion, developmental neurotoxicity of the blood-stasis pregnant mice exposed to Rhizoma Curcumae was weaker than that of the normal pregnant mice. Nrf2 activation involved in the phenomenon of Rhizoma Curcumae of "syndrome-based treatment during pregnancy", but the upstream signal pathway mechanism value shall be further investigated.

Astragaloside IV attenuates lead acetate-induced inhibition of neurite outgrowth through activation of Akt-dependent Nrf2 pathway in vitro.

Recently, oxidative stress is strongly associated with lead (Pb)-induced neurotoxicity. We reported previously that Astragaloside IV (AS-IV) possesses potent antioxidant properties. Here, we evaluate the hypothesis that AS-IV attenuates lead acetate (PbAc)-mediated inhibition of neurite outgrowth might mainly result from its antioxidant property via serine/threonine protein kinase (Akt)-dependent activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Interestingly, AS-IV attenuates PbAc-induced inhibition of neurite outgrowth and displayed potential antioxidant properties by inhibiting reactive oxygen species (ROS). Concomitantly, AS-IV enhanced phase II detoxifying enzymes such as heme oxygenase 1 (HO-1), thioredoxin reductase (TrxR), and glutamate cysteine ligase catalytic subunit (GCLc). Conversely, AS-IV had no effect on GCL modulatory subunit (GCLm) and superoxide dismutase (SOD) activity/expression. Furthermore, AS-IV evoked Akt phosphorylation, and subsequent induced phosphorylation of glycogen synthase kinase-3ß (GSK-3ß) at Ser9 (that is, inactivation), which stimulated Nrf2-mediated antioxidant response element (ARE)-containing activation. Importantly, Akt locates upstream of GSK-3ß and regulates phase II detoxifying enzymes gene expression through Nrf2 nuclear accumulation in PC12 cells exposed to PbAc. Noteworthy, these results were further confirmed through signalling pathway inhibitors, dominant negative mutant and short hairpin RNA technology. Collectively, these in vitro findings suggest that AS-IV attenuates PbAc-induced inhibition of neurite outgrowth attributed to its antioxidant properties and may be a promising candidate for the treatment of lead developmental neurotoxicity.

Rosmarinic acid counteracts activation of hepatic stellate cells via inhibiting the ROS-dependent MMP-2 activity: Involvement of Nrf2 antioxidant system.

Recently, oxidative stress is involved in hepatofibrogenesis. Matrix metalloproteinase-2 (MMP-2) is required for activation of hepatic stellate cells (HSCs) in response to reactive oxygen species (ROS). This study was designed to explore the hypothesis that the inhibitory effect of rosmarinic acid (RA) on HSCs activation might mainly result from its antioxidant capability by increasing the synthesis of glutathione (GSH) involved in nuclear factor kappa B (NF-κB)-dependent inhibition of MMP-2 activity. Here, we demonstrate that RA reverses activated HSCs to quiescent cells. Concomitantly, RA inhibits MMP-2 activity. RNA interference-imposed knockdown of NF-κB abolished down-regulation of MMP-2 by RA. RA-mediated inactivation of NF-κB could be blocked by the diphenyleneiodonium chloride (DPI; a ROS inhibitor). Conversely, transfection of dominant-negative (DN) mutant of extracellular signal-regulated kinases 2 (ERK2), c-Jun N-terminal kinase 1 (JNK1), or p38α kinase had no such effect. Simultaneously, RA suppresses ROS generation and lipid peroxidation (LPO) whereas increases cellular GSH in HSC-T6 cells. Furthermore, RA significantly increased antioxidant response element (ARE)-mediated luciferase activity, nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and catalytic subunits from glutamate cysteine ligase (GCLc) expression, but not modulatory subunits from GCL (GCLm). RA-mediated up-regulation of GClc is inhibited by the shRNA-induced Nrf2 knockdown. The knocking down of Nrf2 or buthionine sulfoximine (a GCL inhibitor) abolished RA-mediated inhibition of ROS. Collectively, these results provide novel insights into the mechanisms of RA as an antifibrogenic candidate in the prevention and treatment of liver fibrosis.

Comparison of the curdione in brain of blood stasis pregnant rats and its offsprings with the normal group rats by UPLC-Q-TOF-MS.

Curdione is a main active component of curcuma rhizomes (Ezhu), which shows an excellent antithrombotic activity. In this study, the concentration of Curdione in pregnant rats and their offspring brain was determined using ultra-performance liquid chromatography-quadrupole time-of-flight/mass spectrometry (UPLC-Q-TOF-MS) method. The water extraction then alcohol precipitation extract from Ezhu was administered through tail intravenous injection. The pharmacokinetic parameters were analyzed to compare the differences between the blood stasis group rats and normal group rats. Using Schisandrol A as an internal standard, samples were extracted using dichloromethane and isopropanol (90:10, v/v). Calibration plot was linear over the range of 0.5-200µg•mL.-1. for Curdione in brain with the lower quantification limit being 0.5µg•mL-1. The recoveries of Curdione and IS from brain were more than 93.31% and 90.90% separately. The RSD for both intra- and inter-day precision were <6.49%, RE were -14.84%~-2.8%. The pharmacokinetic parameters Cmax and AUC among the four kinds of rats had significant difference. The Curdione distributed in rat brain in model group is less than normal group. Ezhu medicine may show the therapeutic effect but not the reproductive toxicity on mother or unborn baby to cure the pregnant women under the adaptive symptoms.

An investigation of the developmental neurotoxic potential of curcumol in PC12 cells.

Curcuma phaeocaulis Val. is a Chinese medicinal herb that is contraindicated during pregnancy for over a thousand years in China. The aims of the present study were to evaluate the effect of curcumol (one of the major components of C. phaeocaulis Val.) on neurite outgrowth and characterize the signal transduction pathways in PC12 cells. Curcumol significantly inhibited neurite outgrowth and cell proliferation, but did not cause cell death at a concentration of 450 µM in differentiated PC12 cells. In addition, curcumol evoked oxidative stress and it was indicated by an elevation in reactive oxygen species (ROS) and lipid peroxidation (LPO). Although PC12 cells exhibited inhibition of the differentiation into the acetylcholine (ACh) phenotype following 450 µM curcumol exposure, there was no significant alteration in net shift toward the ACh phenotype or tyrosine hydroxylase (TH) phenotype was observed. Neural cell adhesion molecule (NCAM)/focal adhesion kinase (FAK) but not extracellular signal-regulated kinases 1 and 2 (ERK1/2) signaling was repressed by curcumol exposure in differentiated PC12 cells. Curcumol does not affect calpain activity and nuclear factor-κB (NF-κB) DNA-binding activity. These findings suggest that curcumol might be a developmental neurotoxicant and NCAM/FAK signaling pathway may play an important role in curcumol-evoked inhibition of neurite outgrowth.

Analyzing 395,793 samples shows significant association between rs999737 polymorphism and breast cancer.

Large-scale genome-wide association studies (GWAS) have been conducted and reported the association between rs999737 polymorphism at 14q24.1 (RAD51L1) and breast cancer risk. Following studies investigated rs999737 polymorphism in European and Asian populations. However, some of these studies reported weak and no significant association. Here, we reevaluated this association using large-scale samples from previous 11 studies (n=395,793; 162,261 cases and 233,532 controls) from the PubMed database. We evaluated the genetic heterogeneity among the selected studies. The pooled odds ratio (OR) is calculated by the fixed effect model. All statistical tests for heterogeneity and meta-analysis were computed using R package. We did not identify significant heterogeneity among the included studies using the allele model (P=0.1314 and I (2)=33.4 %). We observed significant association between rs999737 and breast cancer using the allele model (P=2.47E - 35, OR=0.92, 95 % confidence interval (CI) 0.91-0.93). Our analysis further supports previous findings that the rs999737 polymorphism contributes to breast cancer susceptibility. We believe that our finding will be very useful for future genetic studies in breast cancer.

Natural polyphenol: Their pathogenesis-targeting therapeutic potential in Alzheimer's disease.

Alzheimer's disease (AD) is a detrimental neurodegenerative disease affecting the elderly. Clinically, it is characterized by progressive memory decline and subsequent loss of broader cognitive functions. Current drugs provide only symptomatic relief but do not have profound disease-modifying effects. There is an unmet need to identify novel pharmacological agents for AD therapy. Neuropathologically, the characteristic hallmarks of the disease are extracellular senile plaques containing amyloid ß-peptides and intracellular neurofibrillary tangles containing hyperphosphorylated microtubule-associated protein tau. Simultaneously, oxidative stress, neuroinflammation and mitochondrial dysfunction in specific brain regions are early events during the process of AD pathologic changes and are associated with Aß/tau toxicity. Here, we first summarized probable pathogenic mechanisms leading to neurodegeneration and hopefully identify pathways that serve as specific targets to improve therapy for AD. We then reviewed the mechanisms that underlie disease-modifying effects of natural polyphenols, with a focus on nuclear factor erythroid 2-related factor 2 activators for AD treatment. Lastly, we discussed challenges in the preclinical to clinical translation of natural polyphenols. In conclusion, there is evidence that natural polyphenols can be therapeutically useful in AD through their multifaceted mechanism of action. However, more clinical studies are needed to confirm these effects.

Alteration of the ERK5 pathway by hydroxysafflor yellow A blocks expression of MEF2C in activated hepatic stellate cells in vitro: Potential treatment for hepatic fibrogenesis.

Abstract Context: Hepatic fibrosis ultimately leads to cirrhosis if not treated effectively. Hepatic stellate cells (HSC) are a main mediator of hepatic fibrosis through the accumulation of extracellular matrix proteins. Suppression activation of passaged HSC has been proposed as therapeutic strategies for the treatment and prevention of hepatic fibrosis. Objective: To evaluate the effect of hydroxysafflor yellow A (HSYA), an active chemical compound derived from the flowers of Carthamus tinctorius L. (Compositae), on HSC inhibition, and to begin elucidating underlying mechanisms. Materials and methods: Primary HSCs were isolated from rats by in situ pronase/collagenase perfusion. Culture-activated HSCs were treated with or without HSYA at 30 µM in the presence or absence of PD98059 for 48 h, and then cell proliferation was measured by MTS assays. Messenger RNA (mRNA) expression was quantified by polymerase chain reaction, and protein was quantified by Western blots or enzyme-linked immunosorbent assays. Results: HSYA significantly inhibits culture-activated HSC proliferation in a dose-dependent and time-dependent manner with an IC50 value of 112.79 µM. HSYA (30 µM) induce the suppression of HSC activation, as indicated by decreases in contents of type I alpha collagen in HSC-cultured media and expression of α-smooth muscle actin protein in culture-activated HSC by 55 and 71%, respectively. HSYA (30 µM) also caused significant decreases in mRNA expression of type III alpha collagen in HSC by 28%. HSYA (30 µM) suppresses myocyte enhancer factor 2 C (MEF2C) expression both at its mRNA and protein levels by 60 and 61%, respectively. Further study demonstrated that HSYA (30 µM) caused significant decreases in p-ERK5 by 49%. Blocking extracellular signal-regulated protein kinase 5 (ERK5) activity by XMD 8--92, an ERK5 inhibitor, markedly abrogated the inhibitive effects of HSYA on HSC activation, and blocked the HSYA-mediated MEF2C down-regulation. Conclusions: HSYA suppress HSC activation by ERK5-mediated MEF2C down-regulation and makes it a potential candidate for prevention and treatment of hepatic fibrogenesis.

Lead toxicity and potential therapeutic effect of plant-derived polyphenols.

BACKGROUND: Due to its unique physical and chemical properties, lead is still used worldwide in several applications, especially in industry. Both environmental and industrial lead exposures remain a public health problem in many developing and rapidly industrializing countries. Plant polyphenols are pleiotropic in their function and have historically made a major contribution to pharmacotherapy. PURPOSE: To summarize available pre-clinical and limited clinical evidence on plant polyphenols as potential antidotes against lead poisoning and discuss toxic mechanisms of lead. METHOD: A comprehensive search of peer-reviewed publications was performed from core collections of electronic databases such as PubMed, Web of Science, Google Scholar, and Science Direct. Articles written in English-language from inception until December 2022 were selected. RESULTS: In this review, we review key toxic mechanisms of lead and its pathological effects on the neurological, reproductive, renal, cardiovascular, hematological, and hepatic systems. We focus on plant polyphenols against lead toxicity and involved mechanisms. Finally, we address scientific gaps and challenges associated with translating these promising preclinical discoveries into effective clinical therapies. CONCLUSION: While preclinical evidence suggests that plant polyphenols exhibit bioprotective effects against lead toxicity, scant and equivocal clinical data highlight a need for clinical trials with those polyphenols.

Beta-asarone attenuates beta-amyloid-induced apoptosis through the inhibition of the activation of apoptosis signal-regulating kinase 1 in SH-SY5Y cells.

Beta-amyloid (Abeta) toxicity has been postulated to initiate synaptic loss and subsequent neuronal degeneration seen in Alzheimer's disease (AD). We previously demonstrated that beta-asarone improves cognitive function by suppressing neuronal apoptosis in vivo. In this study, we assessed the neuroprotective effects of beta-asarone against the toxicity of Abeta in relation to the mitochondria-mediated cell death process, and to elucidated the role of the ASK1/MKK7/JNK and mitochondrial pathways in beta-asarone-induced neuroprotection in SH-SY5Y cells. Our results show that beta-asarone afforded protection against Abeta-induced toxicity by inhibiting apoptosis in SH-SY5Y cells. This result was also confirmed by caspase-9 and caspase-3 activity assays. Expression of p-ASK1, p-MKK7, p-JNK, Bax, Bad, and cytochrome c release decreased after pretreatment with beta-asarone in SH-SY5Y cells exposed to A1-42. Interestingly, these effects of beta-asarone against Abeta1-42 insult were enhanced by ASK1 siRNA. These findings suggest that beta-asarone prevents Abeta1-42-induced neurotoxicity through attenuating neuronal apoptosis, and might be a potential preventive or therapeutic agent for AD.

Nrf2 as a potential target for Parkinson's disease therapy.

Parkinson's disease (PD) is a complex neurodegenerative disorder featuring both motor and nonmotor symptoms associated with a progressive loss of dopaminergic neurons in the substantia nigra pars compacta. Conventionally, PD treatment options have focused on dopamine replacement and provide only symptomatic relief. However, disease-modifying therapies are still unavailable. Mechanistically, genetic and environmental factors can produce oxidative stress which has been implicated as a core contributor to the initiation and progression of PD through the degeneration of dopaminergic neurons. Importantly, nuclear factor erythroid 2-related factor 2 (Nrf2) is essential for maintaining redox homeostasis by binding to the antioxidant response element which exists in the promoter regions of most genes coding for antioxidant enzymes. Furthermore, protein kinase C, mitogen-activated protein kinases, and phosphotidylinositol 3-kinase have been implicated in the regulation of Nrf2 activity during PD. Here, we review the evidence supporting the regulation of Nrf2 through Keap1-dependent and Keap1-independent mechanisms. We also address that targeting Nrf2 may provide a therapeutic option to mitigate oxidative stress-associated PD. Finally, we discuss currently known classes of small molecule activators of Nrf2, including Nrf2-activating compounds in PD.

Astragaloside IV-induced Nrf2 nuclear translocation ameliorates lead-related cognitive impairments in mice.

Recently, oxidative stress is a common denominator in the pathogenesis of metal-induced neurotoxicity. Thus, antioxidant therapy is considered as a promising strategy for treating lead-related cognitive impairment. Here, we tested the hypothesis that astragaloside IV (AS-IV) ameliorates lead-associated cognitive deficits through Nrf2-dependent antioxidant mechanisms. Male Nrf2-KO and WT mice received drinking water with 2000 ppm lead and/or AS-IV by gavage for 8 weeks starting at 4 weeks of age. Morris water maze test and biochemical assays were employed to study cognition-enhancing and antioxidant effects of AS-IV. The signaling pathways involved were analyzed using RT-PCR and western blot technology. Significantly, AS-IV attenuated Morris water maze-based cognitive impairment in lead-intoxicated mice. Importantly, cognition-enhancing effect of AS-IV was lost in Nrf2-KO mice. In parallel, AS-IV suppressed lead acetate (PbAc)-induced oxidative stress, as measured by MDA. Mechanistically, AS-IV can up-regulate the expressions of the GCLc and HO-1 at the level of transcription and translation, but not SOD, TrxR activity, GCLm, Trx1, and NQO1 expression. Interestingly, AS-IV induced accumulation of Nrf2 in the nucleus, whereas Nrf2 mRNA levels were unchanged. Furthermore, AS-IV treatment resulted in elevated levels of phosphorylated Akt (active form) and phosphorylated GSK-3ß (inactive forms) but decreased level of phosphorylated Fyn. Collectively, our findings indicate that AS-IV may target Nrf2 to attenuate lead-triggered oxidative stress and subsequent cognitive impairments, suggesting that AS-IV is a potential candidate for the treatment of lead-associated cognitive diseases.

Ferulic acid exerts Nrf2-dependent protection against prenatal lead exposure-induced cognitive impairment in offspring mice.

Prenatal and/or early postnatal exposure to lead (Pb) may be associated with deficits in cognitive function in the toddler offspring, and oxidative stress likely play a central role in mediating these adverse effects. Here, we tested the hypothesis that ameliorative effect of ferulic acid (FA) on lead-induced cognitive deficits attributed to its antioxidant properties in a nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-dependent manner in the context of prenatal Pb exposure. To test this hypothesis, Nrf2 knockout and C57BL/6 wild type mouse dams were exposed/unexposed to PbAc (250 ppm) during gestation day 5 to postnatal day 14 via drinking water, and FA (50 mg/kg)/vehicle was administered orally to dams for 31 d. Spatial learning and memory in pups was assessed by Morris water maze. Biochemical assays, real-time PCR, western blot techniques were employed to evaluate oxidative stress and signaling pathways in the brain of pups. We report that lead acetate (PbAc) leads to deficits in cognitive functions in offspring, which were partially attenuated by FA (P<.05). In parallel, pretreatment with FA also significantly inhibited the PbAc-induced oxidative stress, as indicated by a change in NAD+/NADH ratio, glutathione (GSH) and malondialdehyde contents (all P<.05). Interestingly, FA significantly elevated the glutamate cysteine ligase and heme oxygenase 1 at levels of transcription and translation in both mice exposed and unexposed to Pb, increasing de novo synthesis of GSH (all P<.05). Furthermore, maternal FA administration activates extracellular signal-regulated kinases 1 and 2 and promotes more Nrf2 nuclear accumulation by increasing the Nrf2 total protein in brain of offspring mice (all P<.05). Conversely, FA failed to influence Pb-induced both memory deficits and oxidative stress in offspring of Nrf2 knockout mice (all P≥.05), suggesting that Nrf2 is essential in mediating the cognition-enhancing and antioxidant effects of FA. Overall, our results demonstrate that FA protects against Pb-induced offspring's cognitive deficits, suggesting that it is a promising candidate for the treatment of Pb toxicity.

Beta-asarone improves cognitive function by suppressing neuronal apoptosis in the beta-amyloid hippocampus injection rats.

Elevated levels of beta-amyloid (Abeta) in the brains being a hallmark of Alzheimer's disease (AD) have been believed to play a critical role in the cognitive dysfunction that occurs in AD. Recent evidence suggests that Abeta induces neuronal apoptosis in the brain and in primary neuronal cultures. In this study, we investigated the effects of beta-asarone, the major ingredient of Acorus Tatarinowii Schott, on cognitive function and neuronal apoptosis in Abeta hippocampus injection rats and its mechanism of action. The results show that the Abeta (1-42) injection caused impairments in spatial reference memory in a Morris water maze task and apoptosis in hippocampus. Oral administration of beta-asarone with three different dose (12.5, 25, or 50 mg/kg) for 28 d ameliorated Abeta (1-42)-induced cognitive impairment and reversed the increase of apoptosis in the hippocampus. Abeta-induced c-Jun N-terminal kinase (JNK) results in phosphorylation, subsequent down-regulation of Bcl-2 and Bcl-w expression, and caspase-3 activation. Beta-asarone attenuate Abeta (1-42)-induced neuronal apoptosis in hippocampus by reversal down-regulation of Bcl-2, Bcl-w, caspase-3 activation, and JNK phosphorylation. These results suggest that beta-asarone may be a potential candidate for development as a therapeutic agent to manage cognitive impairment associated with conditions such as Alzheimer's disease.

Beta-asarone attenuates neuronal apoptosis induced by Beta amyloid in rat hippocampus.

Neurodegenerative disorders, such as Alzheimer's disease (AD), is associated with the loss of neuronal cells, and it has been suggested that apoptosis is a crucial pathway in neuronal loss in AD patients. Recent evidence suggests that amyloid beta peptide (Abeta) induces neuronal apoptosis in the brain and in primary neuronal cultures. In this study, we investigated the impact of beta-asarone against the apoptosis induced by Abeta in rat hippocampus. The results showed that intrahippocampal injections of Abeta (1-42) caused apoptosis in rat hippocampus. Oral administration of beta-asarone (12.5, 25, or 50 mg/kg) for 28 d reverse the increase in the number of terminal deoxynucleotidyl transferase dUTP nick-end labeling positive cells in the hippocampus tissue. Mitochondrial dysfunction is a hallmark of beta-amyloid (Abeta)-induced neuronal toxicity in AD. Therefore, we investigated nuclear translocation of apoptosis induction factors. Our results showed that beta-asarone afforded a beneficial inhibition on both mRNA and protein expression of Bad, Bax, and cleavage of caspases 9 in rat hippocampus following intrahippocampal injections of Abeta (1-42). Our further investigation revealed that ASK1, p-MKK7, and p-c-Jun were significantly decreased after beta-asarone treatment, implicating that the modulation of ASK1/c-JNK-mediated intracellular signaling cascades might be involved in therapeutic effect of beta-asarone against Abeta toxicity. Taken together, these results suggest that beta-asarone may be a potential candidate for development as a therapeutic agent for AD.

A low molecular weight polysaccharide isolated from Agaricus blazei Murill (LMPAB) exhibits its anti-metastatic effect by down-regulating metalloproteinase-9 and up-regulating Nm23-H1.

The components of Agaricus blazei Murill (AbM) have been shown to possess antitumor potentials. Herein, we attempted to explore the anti-metastatic effect and underlying mechanism of a low molecular weight polysaccharide isolated from AbM (LMPAB). Matrigel invasion assay was applied to evaluate the effect of LMPAB on migration of BEL-7402 hepatic cancer cells in vitro. In vivo, the anti-metastatic effect of LMPAB was investigated in mouse B16 melanoma and a double-grafted SW180 tumor models. mRNA and protein levels of metalloproteinase-9 (MMP-9) or nm23-H1 upon LMPAB treatment were detected by real-time PCR and immunohistochemistry assays. LMPAB significantly reduced the invasion of BEL-7402 cells. In vivo, LMPAB was revealed to decrease lung metastatic foci in mouse B16 melanoma model. In the double-grafted SW180 mouse tumor model, we further demonstrated that intratumoral treatment of LMPAB inhibited the growth of tumor on treated side but also suppresses the regression of metastatic tumors on the non-treated side. Moreover, LMPAB reduced MMP-9 but enhanced nm23-H1 mRNA and protein expression. LMPAB displays anti-metastatic activities, indicating the potential of its clinical application for the prevention and treatment of cancer metastasis. Its anti-metastatic effect may relate to the modulation on MMP-9 and nm23-H1.

Immunostimulatory activities of a low molecular weight antitumoral polysaccharide isolated from Agaricus blazei Murill (LMPAB) in Sarcoma 180 ascitic tumor-bearing mice.

LMPAB is a linear beta-(1-3)-glucan we isolated from polysaccharide extract of Agaricus blazei Murill (AbM). Effects of LMPAB on splenic natural killer (NK) cell activity, splenocyte proliferation, index of spleen and thymus, IFN-gamma expression in spleen and the concentration of IL-12, IL-18 and TNF-alpha in serum of S180 ascitic tumor-bearing mice were detected. The results showed that intraperitoneal injection of LMPAB (100 mg x kg(-1) x d(-1)) significantly increased the thymus index. LMPAB augmented splenic NK cell activity in a dose-dependent manner (50-200 mg x kg(-1) x d(-1)). The concanavalin A (3 microg/ ml) stimulated splenocyte proliferation was significantly enhanced by LMPAB at dosages of 50, 100 or 200 mg x kg(-1) x d(-1). Further studies showed that LMPAB (50, 100 or 200 mg x kg(-1) x d(-1), 14d) significantly increased the production of IL-12, TNF-alpha, IL-18 and the expression IFN-gamma as determined by ELISA and immunohistochemistry, respectively. These results clearly indicate that the anti-tumor effects of LMPAB are closely associated with up-regulation of activity of NK cells, expression of IFN-gamma in spleen and the systemic level of IL-12, IL-18 and TNF-alpha in tumor-bearing mice.

Astragaloside IV and ferulic acid synergistically promote neurite outgrowth through Nrf2 activation.

Recently, nuclear factor (erythroid-derived 2)-like 2 (Nrf2) have nuclear localization and nuclear exclusion signals and shuttle between the cytoplasm and the nucleus. Thus, we hypothesised that astragaloside IV (AS-IV) induction nuclear import of Nrf2 and ferulic acid (FA) inhibition nuclear export of Nrf2 contribute to synergistic antioxidant effects of combination of FA and AS-IV (FA/AS-IV). Here, we have demonstrated that FA/AS-IV enhances neurite outgrowth of PC12 cells challenged with lead acetate (PbAc) via antioxidant properties in a synergistic manner. Concomitantly, FA/AS-IV significantly promotes Nrf2 activation and induces "phase-II'' enzymes during PbAc toxicity, compared with either FA or AS-IV alone. Interestingly, FA but not AS-IV activates the extracellular signal-regulated kinases 1 and 2 (ERK1/2), leading to an increase in both de novo synthesis of Nrf2 and nuclear import of Nrf2. Simultaneously, AS-IV but not FA suppresses Fyn phosphorylation via Akt-mediated inhibition of GSK-3ß, which inhibited nuclear export of Nrf2. Importantly, dual activation of both ERK1/2 and Akt by FA/AS-IV in PC12 cells challenged with PbAc is mediated by independent mechanisms, which are supported by pharmacological inhibitors. Collectively, these results support the notion that the FA/AS-IV may be promising in therapy for lead developmental neurotoxicity. This combination deserves further study in vivo.

Rosmarinic acid attenuates ß-amyloid-induced oxidative stress via Akt/GSK-3ß/Fyn-mediated Nrf2 activation in PC12 cells.

Oxidative stress is an important pathogenic factor in Alzheimer's disease (AD). Recently, nuclear factor E2-related factor 2 (Nrf2) has emerged as a master regulator for the endogenous antioxidant response, and thus represents an attractive therapeutic target against AD. The aim of this study is to test the hypothesis that rosmarinic acid (RosA) attenuates amyloid-ß (Aß)-evoked oxidative stress through activating Nrf2-inducible cellular antioxidant defense system. Here, we reported that RosA attenuated Aß-induced cellular reactive oxygen species (ROS) generation and lipid hydroperoxides (LPO). Interestingly, knockdown of Nrf2 by plasmid-based short hairpin RNA (shRNA) abrogated, at least in part, RosA-mediated neuroprotection in Aß-challenged PC12 cells. Mechanistically, RosA enhanced the nuclear translocation of Nrf2 and binding to antioxidant response element (ARE) core element but did not induced Nrf2 transcription. Simultaneously, RosA induced a set of Nrf2 downstream target genes encoding phase-II antioxidant enzymes. Furthermore, RosA enhanced protein kinase B (Akt) phosphorylation, glycogen synthase kinase-3ß (GSK-3ß) phosphorylation at Ser9, and Fyn phosphorylation. Noteworthy, pharmacological inhibition or gene knockdown studies demonstrated that Akt locate upstream of GSK-3ß and regulate Nrf2 through Fyn in the context of PC12 cells pre-incubated with RosA following exposed to Aß. Conversely, the antioxidant effects of RosA could be blocked by Akt inhibitors LY294002, GSK-3ß inhibitor LiCl, Nrf2 shRNA, or Fyn shRNA in Aß-challenged PC12 cells. Consequently, the antioxidant effects of RosA are mediated predominantly by Akt/GSK-3ß/Fyn pathway through increased activity of Nrf2. These results suggest, although do not prove, that RosA can be a promising candidate for neuroprotective treatment of AD.