Angelica sinensis and its alkylphthalides induce the detoxification enzyme NAD(P)H: quinone oxidoreductase 1 by alkylating Keap1

Hydroxysafflor yellow A ameliorates alcohol-induced liver injury through PI3K/Akt and STAT3/NF-κB signaling pathways

BACKGROUND

Alcohol-associated liver disease (ALD) is a prevalent liver ailment. It has escalated into a significant public health issue, imposing substantial burdens on medical, economic, and social domains. Currently, oxidative stress, inflammation, and apoptosis are recognized as crucial culprits in improving ALD. Consequently, mitigating these issues has emerged as a promising avenue for enhancing ALD. Hydroxysafflor yellow A (HSYA) is the main ingredient in safflower, showing excellent antioxidative stress, anti-inflammatory, and anti-apoptosis traits. However, there are limited investigations into the mechanisms by which HSYA ameliorates ALD PURPOSE: We investigated whether HSYA, a significant constituent of Asteraceae safflower, exerts antioxidant stress and attenuates inflammation and anti-apoptotic effects through PI3K/Akt and STAT3/NF-κB pathways, thereby ameliorating ALD METHODS: We established two experimental models: an ethanol-induced liver damage mouse model in vivo and a HepG2 cell alcohol injury model in vitro RESULTS: The results demonstrated that HSYA effectively ameliorated liver tissue damage, reduced levels of ALT, AST, LDL-C, TG, TC, and MDA, enhanced HDL-C levels, SOD and GSH activities, reduced ROS accumulation in cells, and activated the Nrf2 pathway, a transcription factor involved in antioxidant defense. By regulating the PI3K/Akt and STAT3/NF-κB pathways, HSYA exhibits notable antioxidative stress, anti-inflammatory, and anti-apoptotic effects, effectively impeding ALD's advancement. To further confirm the regulatory effect of HSYA on PI3K/Akt and downstream signaling pathways, the PI3K activator 740 Y-P was used and was found to reverse the downregulation of PI3K by HSYA CONCLUSION: This study supports the effectiveness of HSYA in reducing ALD by regulating the PI3K/Akt and STAT3/NF-κB pathways, indicating its potential medicinal value.

Phenolic acids from medicinal and edible homologous plants: a potential anti-inflammatory agent for inflammatory diseases

Inflammation has been shown to trigger a wide range of chronic diseases, particularly inflammatory diseases. As a result, the focus of research has been on anti-inflammatory drugs and foods. In recent years, the field of medicinal and edible homology (MEH) has developed rapidly in both medical and food sciences, with 95% of MEH being associated with plants. Phenolic acids are a crucial group of natural bioactive substances found in medicinal and edible homologous plants (MEHPs). Their anti-inflammatory activity is significant as they play a vital role in treating several inflammatory diseases. These compounds possess enormous potential for developing anti-inflammatory drugs and functional foods. However, their development is far from satisfactory due to their diverse structure and intricate anti-inflammatory mechanisms. In this review, we summarize the various types, structures, and distribution of MEHP phenolic acids that have been identified as of 2023. We also analyze their anti-inflammatory activity and molecular mechanisms in inflammatory diseases through NF-κB, MAPK, NLRP3, Nrf2, TLRs, and IL-17 pathways. Additionally, we investigate their impact on regulating the composition of the gut microbiota and immune responses. This analysis lays the groundwork for further exploration of the anti-inflammatory structure-activity relationship of MEHP phenolic acids, aiming to inspire structural optimization and deepen our understanding of their mechanism, and provides valuable insights for future research and development in this field.

Decreased Nrf2 protein level and low sperm quality in intractable spermatocystitis

To investigate the molecular etiology of low sperm quality in patients with intractable spermatocystitis, spermatozoa samples from patients with persistent hematospermia undergoing transurethral seminal vesiculoscopy and healthy volunteers were utilized. Spermatozoa samples were collected from the seminal vesicles through transurethral seminal vesiculoscopy or by masturbation ejaculation. Sperm quality was analyzed by a WLJY-9000 color semen analysis system. Measurement of tumor necrosis factor alpha (TNFα) and interleukin-6 (IL-6) in the seminal plasma was performed using enzyme-linked immunosorbent assay (ELISA). Measurement of H 2 O 2 in the seminal plasma was performed with a hydrogen peroxide kit. The protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and phosphorylated-Nrf2 (p-Nrf2) were measured by western blot analysis and immunofluorescence assays. Low sperm quality parameters and increased levels of inflammatory cytokines (TNFα, IL-6, and H 2 O 2 ) in the seminal plasma were detected among the semen samples from the patients with persistent hematospermia. Nrf2 and p-Nrf2 were strongly expressed in the nucleus and periphery of human sperm cells, according to the results of the immunofluorescence assays. The protein levels of Nrf2 and p-Nrf2 were significantly lower in the spermatozoa samples from patients with persistent hematospermia than in those from healthy volunteers with normal sperm motility. The results suggested that Nrf2 signaling might play a role in the low sperm quality of patients with intractable spermatocystitis.

Phthalides from the rhizome of Ligusticum chuanxiong Hort. attenuate diabetic nephropathy in mice

ETHNOPHARMACOLOGICAL RELEVANCE

In many famous formulas of traditional Chinese medicine (TCM), the rhizome of Ligusticum chuanxiong (L. chuanxiong) is commonly used as an ingredient for promoting blood circulation and resolving blood stasis to treat diabetic nephropathy. However, its material basis and mechanism of action are still needed to be explored.

AIM OF THE STUDY

The aim of this work is to elucidate the potential effective parts (phthalides) of L. chuanxiong responsible for renal protection and to explore the possible mechanism of renal protection.

MATERIALS AND METHODS

A method based on column chromatography of macroporous resin was established to enrich an effective part (LCE70), and the composition of LCE70 was identified by HPLC-UV and UPLC-MS/MS methods. Mice model was induced by streptozotocin (STZ) to evaluate the protective effect of LCE70 on diabetic nephropathy (DN). In vitro, the suppressive effect of LCE70 on oxidative damage, inflammation and its mechanism were tested using immunoblot analysis, ELISA, etc. Cellular thermal shift assay (CETSA) was adopted to verify the interaction between the phthalides and the key targets involved in renal injury.

RESULTS

LCE70 displayed therapeutic potential against metabolic disorders, renal dysfunction, and fibrosis in a DN model induced by STZ in mice. Furthermore, it markedly reduced oxidative stress of the kidney in DN mice by activating Nrf2 pathway. Z-ligustilide, the main component of LCE70, reacted with Keap1, and thus promoted Nrf2 dissociating from Keap1 to activate Nrf2 pathway.

CONCLUSIONS

LCE70 improved hyperglycemia-induced renal function by enhancing the Nrf2 activation, reducing collagen deposition, and alleviating inflammation and oxidative stress, which suggested its potential as a therapeutic agent for DN.

7,8-dihydroxyflavone displayed antioxidant effect through activating HO-1 expression and inhibiting caspase-3/PARP activation in RAW264.7 cells

Flavonoids, which contain a benzo-γ-pyrone (C6-C3-C6) skeleton, have been reported to exhibit effective antioxidant ability. This study aimed to compare the antioxidant activities of 7,8-dihydroxyflavone (7,8-DHF) and 7-hydroxyflavone (7-HF) in H2 O2 , lipopolysaccharide (LPS), or tert-butyl hydroperoxide (t-BHP)-induced RAW264.7 cells, respectively. The antioxidant capacities of 7,8-DHF and 7-HF were firstly evaluated by 2,2-azinobis-3-ethyl-benzothiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Then, reactive oxygen species (ROS), super oxide dismutase (SOD), and malondialdehyde (MDA) productions in H2 O2 , LPS, or t-BHP-induced RAW264.7 cells were tested and compared, respectively. Finally, the antioxidant mechanisms of 7-HF and 7,8-DHF were initially investigated by western blot. Our results showed that 7,8-DHF possessed stronger free-radical scavenging capacity than 7-HF. Both 7,8-DHF and 7-HF suppressed MDA production and ROS accumulation, improved the activity of SOD in H2 O2 , LPS, or t-BHP-induced RAW264.7 cells, respectively. And 7,8-DHF exerted a better antioxidant effect than 7-HF, especially in t-BHP-induced oxidative stress. Mechanically, 7,8-DHF prevented the activation of poly ADP-ribosepolymerase and caspase-3, meanwhile markedly upregulated the expression of HO-1 protein in t-BHP-induced oxidative stress. These results suggested that 7,8-DHF might serve as a potential pharmaceutical drug against oxidative stress injury.

Ligustilide covalently binds to Cys129 of HMGCS1 to ameliorate dyslipidemia

Dyslipidemia is characterized by elevated levels of total cholesterol and triglycerides in serum, and has become the primary human health killer because of the major risk factors for cardiovascular diseases. Although there exist plenty of drugs for dyslipidemia, the number of patients who could benefit from lipid-lowering drugs still remains a concern. Ligustilide (Lig), a natural phthalide derivative, was reported to regulate lipid metabolic disorders. However, its specific targets and underlying molecular mechanism are still unclear. In this study, we found that Lig alleviated high fat diet-induced dyslipidemia by inhibiting cholesterol biosynthesis. Furthermore, a series of chemical biological analysis methods were used to identify its target protein for regulating lipid metabolism. Collectively, 3-hydroxy-3-methylglutaryl coenzyme A synthetase 1 (HMGCS1) of hepatic cells was identified as a target for Lig to regulate lipid metabolism. The mechanistic study confirmed that Lig irreversibly binds to Cys129 of HMGCS1 via its metabolic intermediate 6,7-epoxyligustilide, thereby reducing cholesterol synthesis and improving lipid metabolism disorders. These findings not only systematically elucidated the lipid-lowering mechanism of Lig, but also provided a new structural compound for the treatment of dyslipidemia.

NRF2 modulation in TRAMP mice: an in vivo model of prostate cancer

BACKGROUND

Prostate cancer (PCa) is one of the most common cancers worldwide and oxidative stress is involved in its occurrence, development and progression. In fact, in transgenic adenocarcinoma of mouse prostate (TRAMP) mice, prostate cancer onset is associated with the methylation of the first five CpG in the nuclear factor erythroid 2-related factor 2 (NRF2) promoter, a key regulator of oxidative stress response, leading to its downregulation and accumulation of reactive oxygen species (ROS). It has been demonstrated that both natural and synthetic compounds can reactivate NRF2 expression inhibiting the methylation status of its promoter by downregulation of DNA methyltransferases (DNMTs) and histone deacetylases (HDACs). Interestingly, NRF2 re-expression significantly reduced prostate cancer onset in TRAMP mice highlighting an important role of NRF2 in prostate tumorigenesis.

METHODS AND RESULTS

We analysed the current literature regarding the role of natural and synthetic compounds in modulating NRF2 pathway in TRAMP mice, an in vivo model of prostate cancer, to give an overview on prostate carcinogenesis and its possible prevention.

CONCLUSION

We can conclude that specific natural and synthetic compounds can downregulate DNMTs and/or HDACs inhibiting the methylation status of NRF2 promoter, then reactivating the expression of NRF2 protecting normal prostatic cells from ROS damage and tumorigenesis.

Bacterial Infections Affect Male Fertility: A Focus on the Oxidative Stress-Autophagy Axis

Numerous factors trigger male infertility, including lifestyle, the environment, health, medical resources and pathogenic microorganism infections. Bacterial infections of the male reproductive system can cause various reproductive diseases. Several male reproductive organs, such as the testicles, have unique immune functions that protect the germ cells from damage. In the reproductive system, immune cells can recognize the pathogen-associated molecular patterns carried by pathogenic microorganisms and activate the host's innate immune response. Furthermore, bacterial infections can lead to oxidative stress through multiple signaling pathways. Many studies have revealed that oxidative stress serves dual functions: moderate oxidative stress can help clear the invaders and maintain sperm motility, but excessive oxidative stress will induce host damage. Additionally, oxidative stress is always accompanied by autophagy which can also help maintain host homeostasis. Male reproductive system homeostasis disequilibrium can cause inflammation of the genitourinary system, influence spermatogenesis, and even lead to infertility. Here, we focus on the effect of oxidative stress and autophagy on bacterial infection in the male reproductive system, and we also explore the crosslink between oxidative stress and autophagy during this process.

Enantioselective synthesis of 3-aryl-phthalides through a nickel-catalyzed stereoconvergent cross-coupling reaction

A nickel-catalyzed asymmetric Suzuki-Miyaura cross-coupling of racemic 3-bromo-phthalides and arylboronic acids was realized for the synthesis of diverse chiral 3-aryl-phthalides in moderate to excellent reaction yields. The reaction proceeded in a stereoconvergent manner and high enantioselectivities were observed for most examined examples. A number of functional groups like aldehyde, ester and bromide were well tolerated. Heteroaromatic boronic acids were also competent coupling partners in this reaction.

Molecular Mechanism of Cellular Oxidative Stress Sensing by Keap1

The Keap1-Nrf2 system plays a central role in the oxidative stress response; however, the identity of the reactive oxygen species sensor within Keap1 remains poorly understood. Here, we show that a Keap1 mutant lacking 11 cysteine residues retains the ability to target Nrf2 for degradation, but it is unable to respond to cysteine-reactive Nrf2 inducers. Of the 11 mutated cysteine residues, we find that 4 (Cys226/613/622/624) are important for sensing hydrogen peroxide. Our analyses of multiple mutant mice lines, complemented by MEFs expressing a series of Keap1 mutants, reveal that Keap1 uses the cysteine residues redundantly to set up an elaborate fail-safe mechanism in which specific combinations of these four cysteine residues can form a disulfide bond to sense hydrogen peroxide. This sensing mechanism is distinct from that used for electrophilic Nrf2 inducers, demonstrating that Keap1 is equipped with multiple cysteine-based sensors to detect various endogenous and exogenous stresses.

KEAP1, a cysteine-based sensor and a drug target for the prevention and treatment of chronic disease

Redox imbalance and persistent inflammation are the underlying causes of most chronic diseases. Mammalian cells have evolved elaborate mechanisms for restoring redox homeostasis and resolving acute inflammatory responses. One prominent mechanism is that of inducing the expression of antioxidant, anti-inflammatory and other cytoprotective proteins, while also suppressing the production of pro-inflammatory mediators, through the activation of transcription factor nuclear factor-erythroid 2 p45-related factor 2 (NRF2). At homeostatic conditions, NRF2 is a short-lived protein, which avidly binds to Kelch-like ECH-associated protein 1 (KEAP1). KEAP1 functions as (i) a substrate adaptor for a Cullin 3 (CUL3)-based E3 ubiquitin ligase that targets NRF2 for ubiquitination and proteasomal degradation, and (ii) a cysteine-based sensor for a myriad of physiological and pharmacological NRF2 activators. Here, we review the intricate molecular mechanisms by which KEAP1 senses electrophiles and oxidants. Chemical modification of specific cysteine sensors of KEAP1 results in loss of NRF2-repressor function and alterations in the expression of NRF2-target genes that encode large networks of diverse proteins, which collectively restore redox balance and resolve inflammation, thus ensuring a comprehensive cytoprotection. We focus on the cyclic cyanoenones, the most potent NRF2 activators, some of which are currently in clinical trials for various pathologies characterized by redox imbalance and inflammation.

Synthesis and antifungal activities of 3-substituted phthalide derivatives

In order to obtain novel bioactive compounds with significant antifungal activities, two series of 3-substituted phthalide derivatives were designed and synthesized via reduction, bromine substitution, and etherification. In addition, the antifungal activities of all target compounds against nine phytopathogenic fungi in vitro were tested by using the mycelial growth rate method at the concentration of 50 μg mL−1. Preliminary bioassay tests showed that some compounds exhibited more potent antifungal activities as compared with hymexazol. The preliminary structure-activity relationships (SARs) of all target compounds were also investigated.

Z-Ligustilide protects vascular endothelial cells from oxidative stress and rescues high fat diet-induced atherosclerosis by activating multiple NRF2 downstream genes

BACKGROUND AND AIMS

Oxidative stress-induced endothelial dysfunction is considered to exert a vital role in the development of atherosclerotic coronary heart disease (CHD). NRF2 is a key transcriptional factor against oxidative stress through activation of multiple ARE-mediated genes. Z-Lig is derived from the Ligusticum species with antitumor, anti-inflammation and neuroprotection activities. However, the antioxidant potentials of Z-Lig on endothelial dysfunction and atherosclerosis have not been well elucidated. Therefore, in the present work, we appraise the cytoprotective property and anti-atherosclerosis effect of Z-Lig.

METHODS

Potential NRF2 activators were screened and verified by luciferase reporter gene assay. The protein and mRNA levels of NRF2 and ARE-mediated genes, and GSH/GSSG level in EA.hy926 cells treated with Z-Lig were detected. The cytoprotective property of Z-Lig was assessed in the tert-butyl hydroperoxide (t-BHP)-evoked oxidative stress model. Cell viability and reactive oxygen species (ROS) levels in EA.hy926 cells were determined. An atherosclerosis model induced by HFD was used to determine the anti-atherosclerosis effect of Z-Lig in HFD-fed Ldlr-deficient mice.

RESULTS

In vitro, 100 μM Z-Lig upregulated expressions of NRF2 and ARE-driven genes, promoted accumulation of nuclear NRF2 and unbound NRF2- KEAP1 complex in EA.hy926 cells. Furthermore, Z-Lig alleviated oxidative stress and cell injury caused by t-BHP via stimulation of the NRF2/ARE pathway. In vivo, intervention with 20 mg/kg Z-Lig markedly restrained atherosclerosis progression, including attenuation of HFD-induced atherosclerotic plaque formation, alleviation of lipid peroxidation and increase in antioxidant enzyme activity in aortas of HFD-fed Ldlr^-/- mice. The chemopreventive effects of Z-Lig might be associated with the activation of NRF2 and ARE-driven genes.

CONCLUSIONS

The present study suggested that Z-Lig is an effective NRF2 activator, which can protect vascular endothelial cells from oxidative stress and rescue HFD-induced atherosclerosis.

Itaconate: an emerging determinant of inflammation in activated macrophages

Macrophages play a central role in innate immunity as the first line of defense against pathogen infection. Upon exposure to inflammatory stimuli, macrophages rapidly respond and subsequently undergo metabolic reprogramming to substantially produce cellular metabolites such as itaconate. As a derivate of the tricarboxylic acid cycle, itaconate is derived from the decarboxylation of cis-aconitate mediated by immunoresponsive gene 1 in the mitochondrial matrix. It is well known that itaconate has a direct antimicrobial effect by inhibiting isocitrate lyase. Strikingly, two recent studies published in Nature showed that itaconate markedly decreases the production of proinflammatory mediators in lipopolysaccharide-treated macrophages and ameliorates sepsis and psoriasis in animal models, revealing a novel biological action of itaconate beyond its regular roles in antimicrobial defense. The mechanism for this anti-inflammatory effect has been proposed to involve the inhibition of succinate dehydrogenase, blockade of IκBζ translation and activation of Nrf2. These intriguing discoveries provide a new explanation for how macrophages are switched from a pro- to an anti-inflammatory state to limit the damage and facilitate tissue repair under proinflammatory conditions. Thus, the emerging effect of itaconate as a crucial determinant of macrophage inflammation has important implications in further understanding cellular immunometabolism and developing future therapeutics for the treatment of inflammatory diseases. In this review, we focus on the roles of itaconate in controlling the inflammatory response during macrophage activation, providing a rationale for future investigation and therapeutic intervention.

The Tryptophan Pathway Targeting Antioxidant Capacity in the Placenta

The placenta plays a vital role in fetal development during pregnancy. Dysfunction of the placenta can be caused by oxidative stress and can lead to abnormal fetal development. Preventing oxidative stress of the placenta is thus an important measure to ensure positive birth outcomes. Research shows that tryptophan and its metabolites can efficiently clean free radicals (including the reactive oxygen species and activated chlorine). Consequently, tryptophan and its metabolites are suggested to act as potent antioxidants in the placenta. However, the mechanism of these antioxidant properties in the placenta is still unknown. In this review, we summarize research on the antioxidant properties of tryptophan, tryptophan metabolites, and metabolic enzymes. Two predicted mechanisms of tryptophan's antioxidant properties are discussed. (1) Tryptophan could activate the phosphorylation of p62 after the activation of mTORC1; phosphorylated p62 then uncouples the interaction between Nrf2 and Keap1, and activated Nrf2 enters the nucleus to induce expressions of antioxidant proteins, thus improving cellular antioxidation. (2) 3-Hydroxyanthranilic acid, a tryptophan kynurenine pathway metabolite, changes conformation of Keap1, inducing the dissociation of Nrf2 and Keap1, activating Nrf2 to enter the nucleus and induce expressions of antioxidant proteins (such as HO-1), thereby enhancing cellular antioxidant capacity. These mechanisms may enrich the theory of how to apply tryptophan as an antioxidant during pregnancy, providing technical support for its use in regulating the pregnancy's redox status and enriching our understanding of amino acids' nutritional value.

Effects of bioactive constituents in the Traditional Chinese Medicinal formula Si-Wu-Tang on Nrf2 signaling and neoplastic cellular transformation

BACKGROUND

The nuclear factor erythroid 2-related factor 2 (Nrf2) is a potential molecular target for cancer chemoprevention. Si-Wu-Tang (SWT), a popular traditional Chinese medicine for women's health, was reported with a novel activity of cancer prevention.

PURPOSE

The present study was aimed to identify the bioactive constituents in SWT responsible for the Nrf2 activating and cancer preventive activity and explore the pharmacological mechanisms.

METHODS

Nine compounds detectable from various batches of SWT were ranked using in silico molecular docking based on their ability to interfere the forming of Nrf2-Keap1 complex. The predicted Nrf2 activating effect was validated using the antioxidant response element (ARE) luciferase reporter assay and quantitative RT-PCR analysis for select Nrf2 regulated genes Hmox1, Nqo1 and Slc7a11. The antimutagenic activity of the compounds were determined by the Ames test. The chemopreventive activity of these compounds were assessed on EGF-induced neoplastic transformation of JB6 P+ cells, an established non-cancerous murine epidermal model for studying tumor promotion and identifying cancer preventive agents. These compounds were further characterized using luciferase reporter assay on EGF-induced activation of AP-1, a known transcription factor mediating carcinogenesis.

RESULTS

Three of the nine compounds predicted as Nrf2 activators by molecular docking, gallic acid (GA), Z-liguistilide (LIG), and senkyunolide A (SA), were confirmed with highest potency of increasing the Nrf2/ARE promoter activity and upregulating the expression of Hmox1, Nqo1 and Slc7a11. In addition, GA, LIG and SA exhibited an antimutagenic activity against the direct mutagen 2-nitrofluorene while no mutagenic effects were observed at the same time in Ames test. At nontoxic concentrations, GA, LIG, and SA inhibited EGF-induced neoplastic transformation of JB6 P+ cells. Combined treatment of GA, LIG and SA, in the same ratio as detected in SWT, showed enhanced effect against JB6 transformation compared with that of the single compound alone. GA, LIG and SA, alone or in combination, suppressed EGF-induced activation of AP-1.

CONCLUSION

We identified three bioactive constituents in SWT responsible for the Nrf2 activating and cancer preventive activity. This study provides evidence supporting novel molecular basis of SWT in cancer prevention.

Effect of Angelica sinensis Root Extract on Cancer Prevention in Different Stages of an AOM/DSS Mouse Model

Angelica sinensis root (ASR) extract was obtained to investigate its effects on colorectal carcinogenesis in different stages of an Azoxymethane/Dextran sodium sulphate (AOM/DSS) model. In this study, we showed that ASR extract administration in the initial stage of the AOM/DSS model had cancer preventive effects with decreasing tumor incidence and a high-grade of intraepithelial neoplasia incidence. With respect to DNA damage, the amounts of 8-oxoguanine and γ-H2AX were suppressed in colon tissue. The balance of apoptosis and proliferation was approaching the normal state. In contrast, ASR extract administration in the promotion stage of the AOM/DSS model accelerated the progression of carcinogenesis. The maximum tumor size reached 49.85 ± 25.04 mm³. High-grade pathological changes were significantly increased. Decreased DNA damage and P53 level reflected the disrupted reactive oxygen species (ROS) concentration in colorectal tissue, which led to an imbalance of proliferative and apoptotic relationships. These findings suggested that the cancer-preventive effect of ASR extract may be stage-dependent in the process of carcinogenesis.

Effects of trigonelline inhibition of the Nrf2 transcription factor in vitro on Echinococcus granulosus

The aim of this study was to investigate the impact of trigonelline (TRG) on Echinococcus granulosus, and to explore the inhibition impact of nuclear factor erythroid-2-related factor 2 (Nrf2) signaling pathway on E. granulosus protoscoleces. Echinococcus granulosus protoscoleces were incubated with various concentrations of TRG, and then Nrf2 protein expression and its localization in protoscoleces were detected by western blot analysis and immunofluorescence assay, respectively. Reactive oxygen species (ROS) level in protoscoleces was measured using ROS detection kit. Caspase-3 activity was measured using a caspase-3 activity assay kit, and NAD(P)H quinone oxidoreductase (NQO)-1 and heme oxygenase (HO)-1 activities in protoscoleces were measured by ELISA. The effect of TRG on protoscoleces viability was investigated using 0.1% eosin staining, and ultrastructural alterations in protoscoleces were examined by scanning electron microscopy (SEM). Immunolocalization experiment clearly showed that Nrf2 protein was predominantly present in cells of protoscoleces. TRG treatment reduced NQO-1 and HO-1 activities in protoscoleces, but could increase ROS level at early time. Protoscoleces could not survive when treated with 250 μM TRG for 12 days. SEM results showed that TRG-treated protoscoleces presented damage in the protoscoleces region, including hook deformation, lesions, and digitiform protuberance. Nrf2 protein expression was significantly decreased and caspase-3 activity was clearly increased in protoscoleces treated with TRG for 24 and 48 h, respectively, when compared with that in controls (P < 0.05). Our results demonstrated that TRG had scolicidal activity against E. granulosus protoscoleces. Nrf2 protein was mainly expressed in the cells and TRG could efficiently inhibit the Nrf2 signaling pathway in E. granulosus.

Proteomic Insights on the Metabolism of Penicillium janczewskii during the Biotransformation of the Plant Terpenoid Labdanolic Acid

Plant terpenoids compose a natural source of chemodiversity of exceptional value. Many of these compounds own biological/pharmacological activity, others are regarded as unique chemical skeletons for the synthesis of derivatives with improved properties. Functional chemical modification of terpenoids through biotransformation frequently relies on the use of Ascomycota strains, but information on major cellular responses is still largely lacking. Penicillium janczewskii mediates a stereo-selective hydroxylation of labdanolic acid (LA)-terpenoid found abundantly in Cistus ladanifer-producing 3β-hydroxy-labdanolic acid with yields >90%. Herein, combined analyses of mycelial and extracellular differential proteomes demonstrated that the plant terpenoid increased stress responses, especially against oxidative stress (e.g., accumulation of superoxide dismutase) and apparently altered mitochondria functioning. One putative cytochrome P450 monooxygenase differentially accumulated in the secretome and the terpenoid bioconversion was inhibited in vivo in the presence of a P450 inhibitor. The stereo-selective hydroxylation of the plant terpenoid is likely mediated by P450 enzymes, yet its unequivocal identity remains unclear. To the best of our knowledge, this is the first time that proteomics was used to investigate how a plant terpenoid impacts the metabolism of a filamentous fungus during its efficiently biotransformation. Our findings may encourage the development of new strategies for the valorization of plant natural resources through biotechnology.

Intranasal Pretreatment with Z-Ligustilide, the Main Volatile Component of Rhizoma Chuanxiong, Confers Prophylaxis against Cerebral Ischemia via Nrf2 and HSP70 Signaling Pathways

Z-Ligustilide (Z-LIG) is a major component in Rhizoma Chuanxiong, which has been traditionally used as a health food supplement for the prevention of cerebrovascular disease in China. This study investigates the ability of intranasal Z-LIG pretreatment to enhance protection against neuronal damage in rats with middle cerebral artery occlusion (MCAO) and the role of cellular stress response mechanisms Nrf2 and HSP70. Z-LIG significantly mitigated infarct volume, neurological dysfunction, blood-brain barrier disruption, and brain edema (p < 0.01). Moreover, Z-LIG prevented the loss of collagen IV, occludin, and ZO-1 (p < 0.05) and decreased MMP-2 and -9 levels (p < 0.01). Meanwhile, Z-LIG up-regulated NQO1 and HSP70. Notably, blockage of Nrf2-driven transcription or down-regulation of HSP70 remarkably attenuated the preventive effect of Z-LIG (p < 0.05). Together, intranasal delivery of Z-LIG enhanced protection against ischemic injury via Nrf2 and HSP70 signaling pathways and has prophylactic potential in the population at high risk of stroke.

Botanicals and Their Bioactive Phytochemicals for Women's Health

Botanical dietary supplements are increasingly popular for women's health, particularly for older women. The specific botanicals women take vary as a function of age. Younger women will use botanicals for urinary tract infections, especially Vaccinium macrocarpon (cranberry), where there is evidence for efficacy. Botanical dietary supplements for premenstrual syndrome (PMS) are less commonly used, and rigorous clinical trials have not been done. Some examples include Vitex agnus-castus (chasteberry), Angelica sinensis (dong quai), Viburnum opulus/prunifolium (cramp bark and black haw), and Zingiber officinale (ginger). Pregnant women have also used ginger for relief from nausea. Natural galactagogues for lactating women include Trigonella foenum-graecum (fenugreek) and Silybum marianum (milk thistle); however, rigorous safety and efficacy studies are lacking. Older women suffering menopausal symptoms are increasingly likely to use botanicals, especially since the Women's Health Initiative showed an increased risk for breast cancer associated with traditional hormone therapy. Serotonergic mechanisms similar to antidepressants have been proposed for Actaea/Cimicifuga racemosa (black cohosh) and Valeriana officinalis (valerian). Plant extracts with estrogenic activities for menopausal symptom relief include Glycine max (soy), Trifolium pratense (red clover), Pueraria lobata (kudzu), Humulus lupulus (hops), Glycyrrhiza species (licorice), Rheum rhaponticum (rhubarb), Vitex agnus-castus (chasteberry), Linum usitatissimum (flaxseed), Epimedium species (herba Epimedii, horny goat weed), and Medicago sativa (alfalfa). Some of the estrogenic botanicals have also been shown to have protective effects against osteoporosis. Several of these botanicals could have additional breast cancer preventive effects linked to hormonal, chemical, inflammatory, and/or epigenetic pathways. Finally, although botanicals are perceived as natural safe remedies, it is important for women and their healthcare providers to realize that they have not been rigorously tested for potential toxic effects and/or drug/botanical interactions. Understanding the mechanism of action of these supplements used for women's health will ultimately lead to standardized botanical products with higher efficacy, safety, and chemopreventive properties.

Screening of traditional Chinese medicines with therapeutic potential on chronic obstructive pulmonary disease through inhibiting oxidative stress and inflammatory response

Background

Chronic obstructive pulmonary disease (COPD) is a major public health problem and gives arise to severe chronic morbidity and mortality in the world. Inflammatory response and oxidative stress play dominant roles in the pathological mechanism of COPD, and have been regarded to be two important targets for the COPD therapy. Traditional Chinese medicines (TCMs) possess satisfying curative effects on COPD under guidance of the TCM theory in China, and merit in-depth investigations as a resource of lead compounds.

Methods

One hundred ninety-six of TCMs were collected, and extracted to establish a TCM extract library, and then further evaluated for their potency on inhibitions of oxidative stress and inflammatory response using NADP(H):quinone oxidoreductase (QR) assay and nitric oxide (NO) production assay, respectively.

Results

Our investigation observed that 38 of the tested TCM extracts induced QR activity in hepa 1c1c7 murine hepatoma cells, and 55 of them inhibited NO production in RAW 264.7 murine macrophages at the tested concentrations. Noteworthily, 20 of TCM extracts simultaneously inhibited oxidative stress and inflammatory responses.

Conclusion

The observed bioactive TCMs, particularly these 20 TCMs with dual inhibitory effects, might be useful for the treatment of COPD. More importantly, the results of the present research afford us an opportunity to discover new lead molecules as COPD therapeutic agents from these active TCMs.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-016-1347-y) contains supplementary material, which is available to authorized users.

Preconditioning with Gua Lou Gui Zhi decoction enhances H2O2-induced Nrf2/HO-1 activation in PC12 cells

Spasticity is common in various central neurological conditions, including after a stroke. Such spasticity may cause additional problems, and often becomes a primary concern for afflicted individuals. A number of studies have identified nuclear factor (erythroid-derived 2)-like 2 (Nrf2) as a key regulator in the adaptive survival response to oxidative stress. Elevated expression of Nrf2, combined with heme oxygenase 1 (HO-1) resistance, in the central nervous system is known to elicit key internal and external oxidation protection. Gua Lou Gui Zhi decoction (GLGZD) is a popular traditional Chinese formula with a long history of clinical use in China for the treatment of muscular spasticity following a stroke, epilepsy or a spinal cord injury. However, the mechanism underlying the efficacy of the medicine remains unclear. In the present study, the antioxidative effects of GLGZD were evaluated and the underlying molecular mechanisms were investigated, using hydrogen peroxide (H₂O₂)-induced rat pheochromocytoma cells (PC12 cells) as an in vitro oxidative stress model of neural cells. Upon application of different concentrations of GLGZD, a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay and ATP measurement were conducted to assess the impact on PC12 cell proliferation. In addition, inverted microscopy observations, and the MTT and ATP assessments, revealed that GLGZD attenuated H₂O₂-induced oxidative damage and signaling repression in PC12 cells. Furthermore, the mRNA and protein expression levels of Nrf2 and HO-1, which are associated with oxidative stress, were analyzed using reverse transcription quantitative polymerase chain reaction (PCR) and confocal microscopy. Confocal microscopy observations, as well as the quantitative PCR assay, revealed that GLGZD exerted a neuroprotective function against H₂O₂-induced oxidative damage in PC12 cells. Therefore, the results demonstrated that GLGZD protected PC12 cells injured by H₂O₂, which may be associated with the upregulation of Nrf2 and HO-1 mRNA and protein expression levels in PC12 cells.

Botanical Integrity: The Importance of the Integration of Chemical, Biological, and Botanical Analyses, and the Role of DNA Barcoding

Raw materials, ingredients, and products derived from plants are commonly referred to as herbs or botanicals in both the biomedical literature and the natural products health industry. This overarching term includes the breadth of crude herbs, plant parts, and the ingredients made from them, and also covers finished products such as botanical dietary supplements. Botanical dietary supplements are intended to supplement the human diet and are composed primarily of powdered plant parts, their extracts, or other preparations derived from crude herbal material; some formulations include other ingredients such as vitamins, minerals, and amino acids. Botanical dietary supplements are highly complex mixtures reflecting the diverse chemical constituents that comprise the source plant's raw material. Botanical analysis is an intricate analytical challenge requiring specialized skills and instrumentation that is different from those required for quality control of chemically simpler pharmaceuticals, or for the safety assessment of many conventional food or other products that are generally regarded as safe (GRAS).

Cancer chemoprevention by traditional chinese herbal medicine and dietary phytochemicals: targeting nrf2-mediated oxidative stress/anti-inflammatory responses, epigenetics, and cancer stem cells

Excessive oxidative stress induced by reactive oxygen species (ROS), reactive nitrogen species (RNS), and reactive metabolites of carcinogens alters cellular homeostasis, leading to genetic/epigenetic changes, genomic instability, neoplastic transformation, and cancer initiation/progression. As a protective mechanism against oxidative stress, antioxidant/detoxifying enzymes reduce these reactive species and protect normal cells from endo-/exogenous oxidative damage. The transcription factor nuclear factor-erythroid 2 p45 (NF-E2)-related factor 2 (Nrf2), a master regulator of the antioxidative stress response, plays a critical role in the expression of many cytoprotective enzymes, including NAD(P)H:quinine oxidoreductase (NQO1), heme oxygenase-1 (HO-1), UDP-glucuronosyltransferase (UGT), and glutathione S-transferase (GST). Recent studies demonstrated that many dietary phytochemicals derived from various vegetables, fruits, spices, and herbal medicines induce Nrf2-mediated antioxidant/detoxifying enzymes, restore aberrant epigenetic alterations, and eliminate cancer stem cells (CSCs). The Nrf2-mediated antioxidant response prevents many age-related diseases, including cancer. Owing to their fundamental contribution to carcinogenesis, epigenetic modifications and CSCs are novel targets of dietary phytochemicals and traditional Chinese herbal medicine (TCHM). In this review, we summarize cancer chemoprevention by dietary phytochemicals, including TCHM, which have great potential as a safer and more effective strategy for preventing cancer.

Traditional Chinese medicinal formula Si-Wu-Tang prevents oxidative damage by activating Nrf2-mediated detoxifying/antioxidant genes

Background

Induction of Nrf2-mediated detoxifying/antioxidant genes has been recognized as an effective strategy for cancer chemoprevention. Si-Wu-Tang (SWT), comprising the combination of four herbs, Paeoniae, Angelicae, Chuanxiong and Rehmanniae, is one of the most popular traditional oriental medicines for women’s diseases. The purpose of this study is to determine the effects of SWT on Nrf2 pathway in vitro and in vivo and to identify the active component(s).

Results

Cell viability and apoptosis were analyzed in the non-cancerous breast epithelial cell line MCF-10A after H₂O₂ treatment in the presence or absence of SWT using the Sulphorhodamine B assay, Annexin-V/Propidium iodide staining and flow cytometry. SWT strongly reduced H₂O₂ -induced cytotoxicity and apoptosis in MCF-10A cells. Expression of Nrf2 and Nrf2-regulated genes HMOX1 (heme oxygenase 1) and SLC7A11 (xCT) was evaluated by quantitative RT-PCR, Western Blot and immunocytochemistry. SWT strongly induced Nrf2-regulated genes at mRNA and protein levels and increased the nuclear translocation of Nrf2 in MCF-10A cells. The in vivo pharmacodynamic effect of SWT was evaluated in healthy female Sprague–Dawley rats. Short-term oral administration of SWT (1,000 mg/kg per day for six consecutive days) to rats resulted in an increased expression of Nrf2-regulated genes Hmox1 and Slc7A11 in the liver detected by quantitative RT-PCR. Among nine compounds that have been identified previously in the SWT products, z-liguistilide was discovered as the main component responsible for the effect of Nrf2 activation using the antioxidant response element-luciferase reporter gene assay. Z-liguistilide was confirmed with a high potency to induce Nrf2-regulated genes and Nrf2 nuclear translocation.

Conclusions

Our results demonstrated that SWT and its component z-liguistilide are able to activate the Nrf2 pathway in non-cancerous cells and organs in vitro and in vivo, suggesting that SWT might be an orally effective and nontoxic agent for cancer chemoprevention.

HPLC method with fluorescence detection for the determination of ligustilide in rat plasma and its pharmacokinetics

CONTEXT

Few methods have been reported for the quantification of ligustilide (LIG) in biosamples: the pretreatment of the biological samples were laborious and time-consuming.

OBJECTIVE

A high-performance liquid chromatographic method with fluorescence detection (HPLC-FLD) for the determination of LIG in rat plasma was developed and validated. Pharmacokinetics and bioavailability of LIG were determined by systematic investigation in Sprague-Dawley rats.

MATERIALS AND METHODS

LIG was isolated from the volatile oil of Radix Angelica sinensis and further purified by silica gel column chromatography. Podophyllotoxin was used as an internal standard. The analytes were detected by using fluorescence detection at an excitation and emission wavelength of 290 and 395 nm during 0-4 min, and 336 and 453 nm during 4-14 min, respectively. LIG pharmacokinetics was studied in rats after oral and intravenous administration of 12.5, 25 and 50 mg/kg doses.

RESULTS

Two calibration curves (Y = 133.49 X - 14.27 (r = 0.9995), Y = 145.61 X + 13.76 (r = 0.9996)) were constructed in the range of 2.44-10,000 ng/mL for LIG with a lower limit of quantitation of 2.44 ng/mL. Both intra-day and inter-day precision were less than 6%. Accuracy ranged from 88.93 to 99.52%. The recovery ranged from 89.07 to 99.71%. The absolute bioavailability values were 71.36, 68.26 and 75.44% for oral doses of 12.5, 25 and 50 mg/kg, respectively.

CONCLUSION

The present HPLC-FLD method was rapid, sensitive and reliable. LIG was absorbed and eliminated rapidly in rat.

Epigenetic reactivation of Nrf2 in murine prostate cancer TRAMP C1 cells by natural phytochemicals Z-ligustilide and Radix angelica sinensis via promoter CpG demethylation

Cancer development has been linked to epigenetic modifications of cancer oncogenes and tumor suppressor genes; in advanced metastatic cancers, severe epigenetic modifications are present. We previously demonstrated that the progression of prostate tumors in TRAMP mice is associated with methylation silencing of the Nrf2 promoter and a reduced level of transcription of Nrf2 and Nrf2 target genes. Radix Angelicae Sinensis (RAS; Danggui) is a medicinal herb and health food supplement that has been widely used in Asia for centuries. Z-Ligustilide (Lig) is one of the bioactive components of RAS. We investigated the potential of Lig and RAS to restore Nrf2 gene expression through epigenetic modification in TRAMP C1 cells. Lig and RAS induced the mRNA and protein expression of endogenous Nrf2 and Nrf2 downstream target genes, such as HO-1, NQO1, and UGT1A1. Bisulfite genomic sequencing revealed that Lig and RAS treatment decreased the level of methylation of the first five CpGs of the Nrf2 promoter. A methylation DNA immunoprecipitation assay demonstrated that Lig and RAS significantly decreased the relative amount of methylated DNA in the Nrf2 gene promoter region. Lig and RAS also inhibited DNA methyltransferase activity in vitro. Collectively, these results suggest that Lig and RAS are able to demethylate the Nrf2 promoter CpGs, resulting in the re-expression of Nrf2 and Nrf2 target genes. Epigenetic modifications of genes, including Nrf2, may therefore contribute to the overall health benefits of RAS, including the anticancer effect of RAS and its bioactive component, Lig.

The Nrf2 cell defence pathway: Keap1-dependent and -independent mechanisms of regulation

The transcription factor Nrf2 (NF-E2-related factor 2) plays a vital role in maintaining cellular homeostasis, especially upon the exposure of cells to chemical or oxidative stress, through its ability to regulate the basal and inducible expression of a multitude of antioxidant proteins, detoxification enzymes and xenobiotic transporters. In addition, Nrf2 contributes to diverse cellular functions including differentiation, proliferation, inflammation and lipid synthesis and there is an increasing association of aberrant expression and/or function of Nrf2 with pathologies including cancer, neurodegeneration and cardiovascular disease. The activity of Nrf2 is primarily regulated via its interaction with Keap1 (Kelch-like ECH-associated protein 1), which directs the transcription factor for proteasomal degradation. Although it is generally accepted that modification (e.g. chemical adduction, oxidation, nitrosylation or glutathionylation) of one or more critical cysteine residues in Keap1 represents a likely chemico-biological trigger for the activation of Nrf2, unequivocal evidence for such a phenomenon remains elusive. An increasing body of literature has revealed alternative mechanisms of Nrf2 regulation, including phosphorylation of Nrf2 by various protein kinases (PKC, PI3K/Akt, GSK-3β, JNK), interaction with other protein partners (p21, caveolin-1) and epigenetic factors (micro-RNAs -144, -28 and -200a, and promoter methylation). These and other processes are potentially important determinants of Nrf2 activity, and therefore may contribute to the maintenance of cellular homeostasis. Here, we dissect evidence supporting these Keap1-dependent and -independent mechanisms of Nrf2 regulation. Furthermore, we highlight key knowledge gaps in this important field of biology, and suggest how these may be addressed experimentally.

Modulation of Estrogen Chemical Carcinogenesis by Botanical Supplements used for Postmenopausal Women's Health

Breast cancer risk has been associated with long-term estrogen exposure including traditional hormone therapy (HT, formally hormone replacement therapy). To avoid traditional HT and associated risks, women have been turning to botanical supplements such as black cohosh, red clover, licorice, hops, dong gui, and ginger to relieve menopausal symptoms despite a lack of efficacy evidence. The mechanisms of estrogen carcinogenesis involve both hormonal and chemical pathways. Botanical supplements could protect women from estrogen carcinogenesis by modulating key enzymatic steps [aromatase, P4501B1, P4501A1, catechol-O-methyltransferase (COMT), NAD(P)H quinone oxidoreductase 1 (NQO1), and reactive oxygen species (ROS) scavenging] in estradiol metabolism leading to estrogen carcinogenesis as outlined in Figure 1. This review summarizes the influence of popular botanical supplements used for women's health on these key steps in the estrogen chemical carcinogenesis pathway, and suggests that botanical supplements may have added chemopreventive benefits by modulating estrogen metabolism.

Natural product nitric oxide chemistry: new activity of old medicines

The use of complementary and alternative medicine (CAM) as a therapy and preventative care measure for cardiovascular diseases (CVD) may prove to be beneficial when used in conjunction with or in place of conventional medicine. However, the lack of understanding of a mechanism of action of many CAMs limits their use and acceptance in western medicine. We have recently recognized and characterized specific nitric oxide (NO) activity of select alternative and herbal medicines that may account for many of their reported health benefits. The ability of certain CAM to restore NO homeostasis both through enhancing endothelial production of NO and by providing a system for reducing nitrate and nitrite to NO as a compensatory pathway for repleting NO bioavailability may prove to be a safe and cost-effective strategy for combating CVD. We will review the current state of science behind NO activity of herbal medicines and their effects on CVD.

Mechanism of the Nrf2/Keap1/ARE signaling system

Nrf2 regulates expression of genes containing antioxidant-respons(iv)e element (ARE) in their promoters and plays a pivotal role among all redox-sensitive transcription factors. Nrf2 is constitutively controlled by repressor protein Keap1, which acts as a molecular sensor of disturbances in cellular homeostasis. These molecular patterns are in close interconnection and function as parts of the integrated redox-sensitive signaling system Nrf2/Keap1/ARE. Depending on cellular redox balance, activity of this signaling system changes at the levels of transcription, translation, posttranslational modification, nuclear translocation of transcription factor, and its binding to ARE-driven gene promoters. This review summarizes current conceptions of Nrf2/Keap1/ARE induction and inactivation.

Ligustilide: a novel TRPA1 modulator

TRPA1 is activated by electrophilic compounds such as mustard oil (MO). Here, we demonstrate a bimodal sensitivity of TRPA1 to ligustilide (Lig), an electrophilic volatile dihydrophthalide of dietary and medicinal relevance. Lig is a potent TRPA1 activator and is also capable to induce a modest block of MO activated currents. Aromatization to dehydroligustilide (DH-Lig), as occurs during aging of its botanical sources, reversed this profile, enhancing TRPA1 inhibition and reducing activation. Mutation of the reactive cysteines in mouseTRPA1 (C622S, C642S, C666S) dramatically reduced activation by MO and significantly reduced that by Lig, but had an almost negligible effect on the action of DH-Lig, whose activation mechanism of TRPA1 is therefore largely independent from the alkylation of cysteine residues. Taken together, these observations show that the phthalide structural motif is a versatile platform to investigate the modulation of TRPA1 by small molecules, being tunable in terms of activation/inhibition profile and mechanism of interaction. Finally, the action of Lig on TRPA1 may contribute to the gustatory effects of celery, its major dietary source, and to the pharmacological action of important plants from the Chinese and native American traditional medicines.

Integrated standardization concept for Angelica botanicals using quantitative NMR

Despite numerous in vitro/vivo and phytochemical studies, the active constituents of Angelica sinensis (AS) have not been conclusively identified for the standardization to bioactive markers. Phytochemical analyses of AS extracts and fractions that demonstrate activity in a panel of in vitro bioassays, have repeatedly pointed to ligustilide as being (associated with) the active principle(s). Due to the chemical instability of ligustilide and related issues in GC/LC analyses, new methods capable of quantifying ligustilide in mixtures that do not rely on an identical reference standard are in high demand. This study demonstrates how NMR can satisfy the requirement for simultaneous, multi-target quantification and qualitative identification. First, the AS activity was concentrated into a single fraction by RP-solid-phase extraction, as confirmed by an alkaline phosphatase, (anti-)estrogenicity and cytotoxicity assay. Next, a quantitative (1)H NMR (qHNMR) method was established and validated using standard compounds and comparing processing methods. Subsequent 1D/2D NMR and qHNMR analysis led to the identification and quantification of ligustilide and other minor components in the active fraction, and to the development of quality criteria for authentic AS preparations. The absolute and relative quantities of ligustilide, six minor alkyl phthalides, and groups of phenylpropanoids, polyynes, and poly-unsaturated fatty acids were measured by a combination of qHNMR and 2D COSY. The qNMR approach enables multi-target quality control of the bioactive fraction, and enables the integrated biological and chemical standardization of AS botanicals. This methodology can potentially be transferred to other botanicals with active principles that act synergistically, or that contain closely related and/or constituents, which have not been conclusively identified as the active principles.

Bioactivities of major constituents isolated from Angelica sinensis (Danggui)

Danggui, also known as Angelica sinensis (Oliv.) Diels (Apiaceae), has been used in Chinese medicine to treat menstrual disorders. Over 70 compounds have been isolated and identified from Danggui. The main chemical constituents of Angelica roots include ferulic acid, Z-ligustilide, butylidenephthalide and various polysaccharides. Among these compounds, ferulic acid exhibits many bioactivities especially anti-inflammatory and immunostimulatory effects; Z-ligustilide exerts anti-inflammatory, anti-cancer, neuroprotective and anti-hepatotoxic effects; n-butylidenephthalide exerts anti-inflammatory, anti-cancer and anti-cardiovascular effects.

Discovery of molecular mechanisms of traditional Chinese medicinal formula Si-Wu-Tang using gene expression microarray and connectivity map

To pursue a systematic approach to discovery of mechanisms of action of traditional Chinese medicine (TCM), we used microarrays, bioinformatics and the “Connectivity Map” (CMAP) to examine TCM-induced changes in gene expression. We demonstrated that this approach can be used to elucidate new molecular targets using a model TCM herbal formula Si-Wu-Tang (SWT) which is widely used for women's health. The human breast cancer MCF-7 cells treated with 0.1 µM estradiol or 2.56 mg/ml of SWT showed dramatic gene expression changes, while no significant change was detected for ferulic acid, a known bioactive compound of SWT. Pathway analysis using differentially expressed genes related to the treatment effect identified that expression of genes in the nuclear factor erythroid 2-related factor 2 (Nrf2) cytoprotective pathway was most significantly affected by SWT, but not by estradiol or ferulic acid. The Nrf2-regulated genes HMOX1, GCLC, GCLM, SLC7A11 and NQO1 were upreguated by SWT in a dose-dependent manner, which was validated by real-time RT-PCR. Consistently, treatment with SWT and its four herbal ingredients resulted in an increased antioxidant response element (ARE)-luciferase reporter activity in MCF-7 and HEK293 cells. Furthermore, the gene expression profile of differentially expressed genes related to SWT treatment was used to compare with those of 1,309 compounds in the CMAP database. The CMAP profiles of estradiol-treated MCF-7 cells showed an excellent match with SWT treatment, consistent with SWT's widely claimed use for women's diseases and indicating a phytoestrogenic effect. The CMAP profiles of chemopreventive agents withaferin A and resveratrol also showed high similarity to the profiles of SWT. This study identified SWT as an Nrf2 activator and phytoestrogen, suggesting its use as a nontoxic chemopreventive agent, and demonstrated the feasibility of combining microarray gene expression profiling with CMAP mining to discover mechanisms of actions and to identify new health benefits of TCMs.

Chemistry of the cysteine sensors in Kelch-like ECH-associated protein 1

The protein Kelch-like ECH-associated protein 1 (Keap1) is a cysteine-rich regulatory and scaffold protein. Human Keap1 contains 27 cysteines. Some of these cysteines are believed to mediate derepression of the transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2), which subsequently upregulates phase 2 enzymes, in response to electrophilic/oxidative assault. Some current models depict a highly select group of two and possibly a few more cysteine residues as key sensors. The assumptions and approaches undergirding these models are commented upon. The chemical reactivity of the cysteines of Keap1 toward an array of electrophiles and one oxidant is reviewed. A number of reports in the recent literature of molecules that putatively modify cysteines of Keap1 are also included. Insights into the current molecular basis of electrophile/oxidant activation of the Nrf2 pathway via reaction at cysteines of Keap1 are discussed. Finally, important knowns and unknowns are summarized.