Huangquan Lin

Calycosin orchestrates the functions of Danggui Buxue Tang, a Chinese herbal decoction composing of Astragali Radix and Angelica Sinensis Radix: An evaluation by using calycosin-knock out herbal extract

ETHNOPHARMACOLOGICAL RELEVANCE Danggui Buxue Tang (DBT) is a classical Chinese herbal decoction containing two herbs, Astragali Radix (AR) and Angelicae Sinensis Radix (ASR), which serves as dietary supplement for treating women menopausal syndromes. Pharmacological studies indicate that DBT has estrogenic, erythropoietic and osteogenic properties; however, the action mechanism for this complex herbal decoction is not known. Calycosin, a major flavonoid in AR, shares similar structure with β-estradiol, and thus which is hypothesized to be the critical compound of DBT. Here, we aim to investigate the role of calycosin in DBT in terms of its biological functions by using a calycosin-depleted DBT decoction (DBT(Δcal)). The biological functions of DBT(Δcal) and parental DBT were systematically compared. MATERIALS AND METHODS In order to standardize DBT decoction, four chemical markers were determined and quantified by HPLC. A semi-preparative HPLC method was utilized to prepare DBT(Δcal). The authenticity of DBT(Δcal) was evaluated by LC-QQQ-MS/MS. To reveal the effect of calycosin on DBT functions, several cell assays related to the known properties of DBT were revealed, including estrogenic, erythropoietic and osteogenic functions. RESULTS As compared to parental DBT, the estrogenic, erythropoietic and osteogenic abilities were markedly reduced in DBT(Δcal). However, calycosin alone did not show significant responses. CONCLUSIONS Our results suggest that calycosin is a bioactive chemical in DBT decoction, and which could play a key linker in orchestrating multi-components of DBT as to achieve maximal functions. These discoveries should be invaluable in drug development and in investigating the modernization of traditional Chinese medicine from a new perspective.

Asarone from Acori Tatarinowii Rhizoma Potentiates the Nerve Growth Factor-Induced Neuronal Differentiation in Cultured PC12 Cells: A Signaling Mediated by Protein Kinase A

Acori Tatarinowii Rhizoma (ATR), the rhizome of Acorus tatarinowii Schott, is being used clinically to treat neurological disorders. The volatile oil of ATR is being considered as an active ingredient. Here, α-asarone and β-asarone, accounting about 95% of ATR oil, were evaluated for its function in stimulating neurogenesis. In cultured PC12 cells, application of ATR volatile oil, α-asarone or β-asarone, stimulated the expression of neurofilaments, a bio-marker for neurite outgrowth, in a concentration-dependent manner. The co-treatment of ATR volatile oil, α-asarone or β-asarone, with low concentration of nerve growth factor (NGF) potentiated the NGF-induced neuronal differentiation in cultured PC12 cells. In addition, application of protein kinase A inhibitors, H89 and KT5720, in cultures blocked the ATR-induced neurofilament expression, as well as the phosphorylation of cAMP-responsive element binding protein (CREB). In the potentiation of NGF-induced signaling in cultured PC12 cells, α-asarone and β-asarone showed synergistic effects. These results proposed the neurite-promoting asarone, or ATR volatile oil, could be useful in finding potential drugs for treating various neurodegenerative diseases, in which neurotrophin deficiency is normally involved.

Optimizing the compatibility of paired-herb in an ancient Chinese herbal decoction Kai-Xin-San in activating neurofilament expression in cultured PC12 cells.

ETHNOPHARMACOLOGICAL RELEVANCE Kai-Xin-San (KXS), a well-known traditional Chinese herbal decoction, has been widely used to treat mental depression and memory loss in China. It has a combination of four herbs: Ginseng Radix et Rhizoma (GR; root and rhizome of Panax ginseng C. A. Mey.), Polygalae Radix (PR; root of Polygala tenuifolia Wild.), Acori Tatarinowii Rhizoma (ATR; rhizome of Acorus tatarinowii Schott), and Poria (PO; sclerotium of Poriacocos (Schw.) Wolf), from which a pairing of two herbs was considered as paired-herb, such as the pairing of GR-PR and ATR-PO. The depression-induced neural cell loss is one of the major pathogenesis in depression. Here, an optimized KXS by changing the ratio of paired-herbs in KXS was demonstrated aiming at promoting neural cell differentiation. MATERIALS AND METHODS Quantitative assessment of chemical markers in each herbal extract was determined by LC-MS. Promoters of neurofilaments, NF68 and NF200, linked with luciferase reporter gene (pNF68-Luc and pNF200-Luc) were applied in cultured pheochromocytoma (PC12) cells to study the transcriptional activation of each herbal extract. The effect of GR-PR and ATR-PO in improving NF promoter activity was analyzed by Compusyn software. The activation of PKA was indicated. RESULTS In PC12 cells, an optimized KXS named KXS1:5 having 1:5 of GR-PR:ATR-PO had greater capability in promoting the expression of neurofilament. The synergistic effect of GR-PR and ATR-PO on the improved efficiency was further determined. Moreover, the treatment of H89, a PKA inhibitor, significantly inhibited the induced NF promoter activity. CONCLUSION These results indicated an optimized KXS by optimizing the compatibility of paired-herb and this compatibility was proven to exert synergistic effect. Moreover, the underlying mechanism was mediated by a PKA signaling pathway.

Yu Ping Feng San, an Ancient Chinese Herbal Decoction, Induces Gene Expression of Anti-viral Proteins and Inhibits Neuraminidase Activity

Yu Ping Feng San (YPFS), a Chinese herbal decoction comprised of Astragali Radix (Huangqi), Atractylodis Macrocephalae Rhizoma (Baizhu) and Saposhnikoviae Radix (Fangfeng), has been used clinically for colds and flus; however, the action mechanism of which is not known. Previously, we had demonstrated that YPFS could modulate inflammatory response and phagocytosis in exerting anti‐viral and anti‐bacterial effects. Here, we further evaluated the bioactivities of YPFS in gene expression regulated by interferon (IFN) signaling and neuraminidase activity of influenza virus A. Application of YPFS onto cultured murine macrophages, the expressions of mRNAs encoding ribonuclease L (RNaseL), myxovirus (influenza virus) resistance 2 (Mx2), protein kinase R (PKR) and IFN‐stimulated gene 15 (ISG15) were induced from 2 to 30 folds in dose‐dependent manners. In parallel, the transcriptional activity of IFN‐stimulated response element (ISRE), an up stream regulator of the above anti‐viral proteins, was also triggered by YPFS treatment. Conversely, YPFS was found to suppress the neuraminidase activity of influenza virus A in cultured epithelial cells, thereby preventing the viral release and spreading. Taken together, YPFS exerted anti‐bacterial and anti‐viral effects in innate immunity. Copyright

Discovery of FDA-approved drugs as inhibitors of fatty acid binding protein 4 using molecular docking screening

We first identified fluorescein, ketazolam, antrafenine, darifenacin, fosaprepitant, paliperidone, risperidone, pimozide, trovafloxacin, and levofloxacin as inhibitors of fatty acid binding protein 4 using molecular docking screening from FDA-approved drugs. Subsequently, the biochemical characterizations showed that levofloxacin directly inhibited FABP4 activity in both the in vitro ligand displacement assay and cell-based function assay. Furthermore, levofloxacin did not induce adipogenesis in adipocytes, which is the major adverse effect of FABP4 inhibitors.

Pimozide, a novel fatty acid binding protein 4 inhibitor, promotes adipogenesis of 3T3-L1 cells by activating PPARγ

Pimozide is a conventional antipsychotic of the diphenylbutylpiperidine class that has been clinically used for over 30 years. The obvious side effect of this drug is weight gain. However, the mechanism of pimozide-induced weight gain is still unknown. In the present study, we identified pimozide as a novel fatty acid binding protein 4 (FABP4) inhibitor using molecular docking simulation as well as biochemical characterizations. BMS309403, a well-known FABP4 inhibitor, elevated the basal protein levels of PPARγ, therefore stimulating adipogenesis in adipocytes. The present study showed that the inhibitory effect of pimozide on FABP4 promoted adipocyte differentiation with the potency proportional to their propensities for weight gain. These effects in adipogenesis by pimozide may help to explain the weight gain that is frequently observed in patients treated with pimozide.

Jujube-containing herbal decoctions induce neuronal differentiation and the expression of anti-oxidant enzymes in cultured PC12 cells

ETHNOPHARMACOLOGICAL RELEVANCE The fruit of Ziziphus jujuba (Mill.), known as Jujuba Fructus (JF) or jujube, is a well-known Traditional Chinese Medicine (TCM) for blood nourishment and sedation effect. Apart from prescribing as single herb alone, JF is very often being included in multi-herbal decoctions to prolong, enhance and harmonize pharmaceutical effects of decoctions while at the same time reducing toxicity. Here, we aimed to compare the protective and differentiating activities of three chemically standardized jujube-containing decoctions, including Guizhi Tang (GZT), Neibu Dangguijianzhong Tang (NDT) and ZaoTang (ZOT) in cultured PC12 cells. MATERIALS AND METHODS The protein expressions of neurofilaments, including NF68, NF160 and NF200, under the herbal treatment were revealed by western blot. The determination of neurite outgrowth in cultured PC12 cells upon the treatment of herbal extracts was performed by light microscope equipped with a phase-contrast condenser and SPOT imaging software. The protective effect against tBHP-induced cytotoxicity under the herbal treatment was measured by MTT assay. A luciferase reporter construct carrying four repeats of anti-oxidant response element (ARE) and a downstream luciferase reporter gene luc2P was transfected into PC12 cells to study the transcriptional activation of ARE. The mRNA expression of antioxidant enzymes under the herbal treatment was analyzed by quantitative real-time PCR. RESULTS These jujube-containing decoctions processed similar neuro-protective and brain beneficial properties. The herbal treatment induced the protein expression of neurofilaments. Neurite outgrowth was observed under the herbal treatment. In parallel, the pre-treatment of herbal extracts protected PC 12 cells against oxidative stress-induced apoptosis in a dose-dependent manner. Moreover, the herbal treatments triggered the mRNA expressions of relevant anti-oxidation genes, i.e. glutamate-cysteine ligase catalytic subunit (GCLC), glutamate-cysteine ligase modulatory subunit (GCLM), glutathione S-transferase (GST) and NAD(P)H quinone oxidoreductase (NQO1) via the activation of anti-oxidant response element (ARE). CONCLUSION The results therefore demonstrated neuro-protective and differentiating properties of the three closely related decoctions, and which subsequently illustrated the enhancement function of jujube within a multi-herbal decoction.

Chemical and biological assessment of Jujube (Ziziphus jujuba)-containing herbal decoctions: Induction of erythropoietin expression in cultures

Jujubae Fructus, known as jujube or Chinese date, is the fruit of Ziziphus jujuba (Mill.), which not only serves as daily food, but acts as tonic medicine and health supplement for blood nourishment and sedation. According to Chinese medicine, jujube is commonly included in herbal mixtures, as to prolong, enhance and harmonize the efficiency of herbal decoction, as well as to minimize the toxicity. Here, we aim to compare the chemical and pharmacological properties of three commonly used jujube-containing decoctions, including Guizhi Tang (GZT), Neibu Dangguijianzhong Tang (NDT) and Zao Tang (ZOT). These decoctions share common herbs, i.e. Glycyrrhizae Radix et Rhizoma Praeparata cum Melle, Zingiberis Rhizoma Recens and Jujube, and they have the same proposed hematopoietic functions. The amount of twelve marker biomolecules deriving from different herbs in the decoctions were determined by LC-MS, and which served as parameters for chemical standardization. In general, three decoctions showed common chemical profiles but with variations in solubilities of known active ingredients. The chemical standardized decoctions were tested in cultured Hep3B cells. The herbal treatment stimulated the amount of mRNA and protein expressions of erythropoietin (EPO) via the activation of hypoxia response elements: the three herbal decoctions showed different activation. The results therefore demonstrated the hematopoietic function of decoctions and explained the enhancement of jujube function within a herbal mixture.

Danggui Buxue Tang (Astragali Radix and Angelicae Sinensis Radix) for menopausal symptoms: A review

BACKGROUND Traditional Chinese medicine (TCM) has contributed greatly to human health in past several thousand years. Today, the development of TCM is facing two obstacles: (i) quality control of herbal extract; and (ii) action mechanisms not known. OBJECTIVES Among thousands of complex TCM formulations, Danggui Buxue Tang (DBT) is the simplest one. DBT is used to treat ailments in women and contains only two herbs, Astragali Radix (Huangqi; AR) and Angelicae Sinensis Radix (Danggui; ASR). The weight ratio of AR to ASR in DBT must be 5:1, as stipulated in AD 1247. By using DBT as a model formula, we develop a strategy to reveal the complexity of a traditional TCM formula. RESULTS There are 3 levels of research directions: (i) the preparation of DBT and its rationale behind; (ii) the traditional theory of DBT is elucidated by chemical and biological determinations; and (iii) the action mechanisms of DBT are revealed. CONCLUSION Through the chemical, biological, genomic and proteomic studies, a possible direction in resolving the preparation mythologies, pharmacological and mechanistic analyses of a TCM decoction is being proposed here.

Clivorine, an Otonecine Pyrrolizidine Alkaloid from Ligularia Species, Impairs Neuronal Differentiation via NGF-Induced Signaling Pathway in Cultured PC12 Cells

BACKGROUND Pyrrolizidine alkaloids (PAs) are commonly found in many plants including those used in medical therapeutics. The hepatotoxicities of PAs have been demonstrated both in vivo and in vitro; however, the neurotoxicities of PAs are rarely mentioned. PURPOSE In this study, we aimed to investigate in vitro neurotoxicities of clivorine, one of the PAs found in various Ligularia species, in cultured PC12 cells. STUDY DESIGN PC12 cell line was employed to first elucidate the neurotoxicity and the underlying mechanism of clivorine, including cell viability and morphology change, neuronal differentiation marker and signaling pathway. METHODS PC12 cells were challenged with series concentrations of clivorine and/or nerve growth factor (NGF). The cell lysates were collected for MTT assay, trypan blue staining, immunocytofluorescent staining, qRT-PCR and western blotting. RESULTS Clivorine inhibited cell proliferation and neuronal differentiation evidenced by MTT assay and dose-dependently reducing neurite outgrowth, respectively. In addition, clivorine decreased the level of mRNAs encoding for neuronal differentiation markers, e.g. neurofilaments and TrkA (NGF receptor). Furthermore, clivorine reduced the NGF-induced the phosphorylations of TrkA, protein kinase B and cAMP response element-binding protein in cultured PC12 cells. CONCLUSION Taken together, our results suggest that clivorine might possess neurotoxicities in PC12 cells via down-regulating the NGF/TrkA/Akt signaling pathway. PAs not only damage the liver, but also possess neurotoxicities, which could possibly result in brain disorders, such as depression.