Gastrodin Attenuates Colitis and Prevents Tumorigenesis in Mice by Interrupting TLR4/MD2/NF-κB Signaling Transduction.

INTRODUCTION: Chronic inflammation is one of the causative factors for tumorigenesis. Gastrodin is a main active ingredient isolated from Gastrodia elata Blume, a famous medicinal herb with a long edible history. AIM: This study aimed to explore the effects of gastrodin on colitis-associated carcinogenesis (CRC) in mice and to elucidate its potential molecular mechanisms. METHODS: Balb/c mice were induced with azoxymethane (AOM) and dextran sulfate sodium (DSS) for 12 weeks. Gastrodin (50 mg/kg) was administered via oral gavage three times per week until the end of the experiment. Disease indexes, including body weight, bloody diarrhea, colon length, histopathological score, and tumor size, were measured. Tumor cell proliferation was evaluated by BrdU incorporation assay and tumor cell cytotoxicity was assessed by cell counting kit (CCK-8). The expression levels of toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) signaling molecules, NF-κB luciferase, and pro-inflammatory cytokines were determined by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), immunoblotting, immunohistochemistry (IHC), enzyme-linked immunosorbent assay (ELISA), or reporter gene assays. The binding affinity between gastrodin and myeloid differentiation protein-2 (MD2) was analyzed by molecular docking and cellular thermal shift assay (CETSA). RESULTS: Gastrodin administration was demonstrated to mitigate various CRC-related symptoms in mice, including weight loss, diarrhea, and tissue abnormalities. Notably, gastrodin suppressed tumor cell growth during colitis- associated tumorigenesis, resulting in fewer and smaller adenomas in the colon. Unlike irinotecan, a broadspectrum antitumor drug, gastrodin did not exhibit apparent cytotoxicity in various colorectal adenocarcinoma cell lines. Additionally, gastrodin downregulated TLR4/NF-κB signaling molecules and pro-inflammatory mediators in mice and macrophages. Molecular docking and CETSA experiments suggested that gastrodin binds to the MD2 protein, potentially interfering with the recognition of lipopolysaccharide (LPS) by TLR4, leading to NF-κB pathway inhibition. CONCLUSION: This study provides evidence for the first time that gastrodin attenuated colitis and prevented colitisrelated carcinogenesis in mice, at least partially, by diminishing tumor-promoting cytokines through the interruption of TLR4/MD2/NF-κB signaling transduction.

Selective hydrodeoxygenation of lignin model compound (3,4-dimethoxybenzyl alcohol) by Pd/CNX catalyst.

Upgrading of lignin derived bio-oil is an essential step for producing sustainable bio-based chemicals and fuel. Taken into account that α hydroxyl is the abundant functional group in lignin, high effective and selective catalytic alcoholysis for cleaving the Cα-OH linkages would be desirable. However, an in-depth understanding of the reaction mechanisms involved in the cleavage of Caromatic-Cα and Cα-O bonds over a novel catalyst is still needed. Herein, we report an efficient liquid-phase hydrogen transfer strategy for the selective hydrodeoxygenation of a non-phenolic lignin model compound, 3,4-dimethoxybenzyl (veratryl) alcohol, under mild conditions. By employing iso-propanol as solvent and H-donor, and palladium nanoparticles immobilized on nitrogen-doped carbon (Pd/CNX) as efficient multifunctional catalyst, veratryl alcohol dehydroxylation exhibited almost 100% conversion along with very high selectivity for 1,2-dimethoxy-benzene (46%) and 3,4-dimethoxytoluene (54%). Compared with other Pd catalysis, the Pd/CNX has excellent catalytic performances and exhibits higher selectivity for 3,4-dimethoxytoluene under incorporation with 1% HCOOH at 220 °C. The proportion of Pd (0) significantly increases in Pd/CNX catalyst when introduced into N precursor because of its highly dispersed Pd NPs and preventing the reoxidation of Pd (0). The dehydrogenation reaction occurred through the hydrogen generation of a secondary alcohol. Then, the Cα-OH and Caromatic-Cα bonds of veratryl alcohol were selectively cleaved by catalytic transfer hydrogenolysis. The alcoholysis mechanism is supported by dispersion-corrected density functional theory computations.

Enantioselective Hydroxylation of Benzylic C(sp3)-H Bonds by an Artificial Iron Hydroxylase Based on the Biotin-Streptavidin Technology.

The selective hydroxylation of C-H bonds is of great interest to the synthetic community. Both homogeneous catalysts and enzymes offer complementary means to tackle this challenge. Herein, we show that biotinylated Fe(TAML)-complexes (TAML = Tetra Amido Macrocyclic Ligand) can be used as cofactors for incorporation into streptavidin to assemble artificial hydroxylases. Chemo-genetic optimization of both cofactor and streptavidin allowed optimizing the performance of the hydroxylase. Using H2O2 as oxidant, up to ∼300 turnovers for the oxidation of benzylic C-H bonds were obtained. Upgrading the ee was achieved by kinetic resolution of the resulting benzylic alcohol to afford up to >98% ee for (R)-tetralol. X-ray analysis of artificial hydroxylases highlights critical details of the second coordination sphere around the Fe(TAML) cofactor.

Miyabeacin: A new cyclodimer presents a potential role for willow in cancer therapy.

Willow (Salix spp.) is well known as a source of medicinal compounds, the most famous being salicin, the progenitor of aspirin. Here we describe the isolation, structure determination, and anti-cancer activity of a cyclodimeric salicinoid (miyabeacin) from S. miyabeana and S. dasyclados. We also show that the capability to produce such dimers is a heritable trait and how variation in structures of natural miyabeacin analogues is derived via cross-over Diels-Alder reactions from pools of ortho-quinol precursors. These transient ortho-quinols have a role in the, as yet uncharacterised, biosynthetic pathways around salicortin, the major salicinoid of many willow genotypes.

Pharmacological Effects of 1'-Acetoxychavicol Acetate, a Major Constituent in the Rhizomes of Alpinia galanga and Alpinia conchigera.

1'-Acetoxychavicol acetate (ACA) is found in the rhizomes or seeds of Alpinia galanga and Alpinia conchigera, which are used as traditional spices in cooking and traditional medicines in Southeast Asia. ACA possesses numerous medicinal properties. Those include anticancer, antiobesity, antiallergy, antimicrobial, antidiabetic, gastroprotective, and anti-inflammatory activities. ACA is also observed to exhibit antidementia activity. Recent studies have demonstrated that combining ACA with other substances results in synergistic anticancer effects. The structural factors that regulate the activity of ACA include (1) the acetyl group at position 1', (2) the acetyl group at position 4, and (3) the unsaturated double bond between positions 2' and 3'. ACA induces the activation of AMP-activated protein kinase (AMPK), which regulates the signal transduction pathways, and has an important role in the prevention of diseases, including cancer, obesity, hyperlipidemia, diabetes, and neurodegenerative disorders. Such findings suggest that AMPK has a central role in different pharmacological functions of ACA, and ACA is useful for the prevention of life-threatening diseases. However, more studies should be performed to evaluate the clinical effects of ACA and to better understand its potential.

United States Pharmacopeia Safety Review of Willow Bark.

Willow bark (Salix spp.) is an ingredient in some dietary supplements. No serious adverse effects were reported from trials of willow bark extracts delivering 120 - 240 mg salicin (the purported active constituent) daily for up to 8 weeks. All studies involved adults only; none involved special subpopulations such as pregnant or breastfeeding women, or children. The most common adverse effects associated with willow bark are gastrointestinal; a few allergic reactions were also reported. Some publications advise caution when taking willow bark. There is a risk of increased bleeding in vulnerable individuals, salicylates cross the placenta and are eliminated slowly in newborns, some persons are sensitive or allergic to aspirin, and children are at risk of Reye syndrome. Concurrent use with other salicylate-containing medicines increases these risks. Metabolism of 240 mg salicin from willow bark could yield 113 mg of salicylic acid, yet dietary supplement products are not required to be labeled with warnings. In contrast, over-the-counter low-dose aspirin (81 mg strength), which delivers 62 mg salicylic acid, is required by law to include cautions, warnings, and contraindications related to its use in pregnant and nursing women, children, and other vulnerable subpopulations, e.g., those using anticoagulants. In the interest of protecting public health, the United States Pharmacopeia has included a cautionary labeling statement in the United States Pharmacopeia Salix Species monograph as follows: "Dosage forms prepared with this article should bear the following statement: 'Not for use in children, women who are pregnant or nursing, or by persons with known sensitivity to aspirin.'".

Mechanochemical Synthesis of CuO/MgAl2O4 and MgFe2O4 Spinels for Vanillin Production from Isoeugenol and Vanillyl Alcohol.

CuO/MgAl2O4 and CuO/MgFe2O4 catalysts were successfully synthesized with the use of spinel supports by a very simple and low-cost mechanochemical method. High-speed ball-milling was used to synthesize these catalyst supports for the first time. Materials were subsequently characterized by using XRD, FESEM, TEM, EDS-Dot mapping, XPS, BET-BJH, and Magnetic Susceptibility to investigate the physical-chemical characteristics of the catalysts. Acidity evaluation results indicated that the catalyst with the Mg-Al spinel support had more acid sites. XRD results showed a successful synthesis of the catalysts with large crystal sizes. Both catalysts were used in isoeugenol oxidation and vanillyl alcohol to vanillin reactions, with the CuO/MgAl2O4 showing optimum results. This catalyst provided 67% conversion (74% selectivity) after 2 h and this value improved to 81% (selectivity 100%) with the second reaction after 8 h. The CuO/MgFe2O4 catalyst in the first reaction after five hours revealed 53% conversion (47% selectivity) and after eight hours with the second reaction, the conversion value improved to 64% (100% selectivity). In terms of reusability, CuO/MgAl2O4 showed better results than the CuO/MgFe2O4 catalyst, for both reactions.

Optimal Extraction Study of Gastrodin-Type Components from Gastrodia Elata Tubers by Response Surface Design with Integrated Phytochemical and Bioactivity Evaluation.

Gastrodia elata tuber (GET) is a popular traditional Chinese medicines (TCMs). In this study, response surface methodology (RSM) with a Box⁻Behnken design (BBD) was performed to optimize the extraction parameters of gastrodin-type components (gastrodin, gastrodigenin, parishin A, parishin B, parishin C and parishin E). Different from the conventional studies that merely focused on the contents of phytochemical, we gave consideration to both quantitative analysis of the above six components by HPLC and representative bioactivities of GET, including antioxidation and protection of human umbilical vein endothelial cells (HUVEC). Four independent variables (ethanol concentration, liquid-material ratio, soaking time and extraction time) were investigated with the integrated evaluation index of phytochemical contents. With the validation experiments, the optimal extraction parameters were as follows: ethanol concentration of 41%, liquid⁻solid ratio of 28.58 mL/g, soaking time of 23.91 h and extraction time of 46.60 min. Under the optimum conditions, the actual standardized comprehensive score was 1.8134 ± 0.0110, which was in accordance with the predicted score of 1.8100. This firstly established method was proved to be feasible and reliable to optimize the extraction parameters of the bioactive components from GET. Furthermore, it provides some reference for the quality control and extraction optimization of TCMs.

Four new phenolic constituents from the rhizomes of Gastrodia elata Blume.

Four new gastrodin derivatives containing a trans-cinnamoyl unit (1-4) and nine known compounds (5-13) were isolated from the rhizomes of Gastrodia elata Blume. All these compounds were evaluated for their neuroprotective effects against 6-hydroxydopamine-induced cell death, and compounds 7 and 12 showed potent activities with EC50 values of 10.5 and 10.2 µM, respectively.

Enhanced Solubility and Permeability of Salicis cortex Extract by Formulating as a Microemulsion.

A microemulsion system was developed and investigated as a novel oral formulation to increase the solubility and absorption of Salicis cortex extract. This extract possesses many pharmacological activities, in particular, it is beneficial for back pain and osteoarthritic and rheumatic complaints. In this work, after qualitative and quantitative characterization of the extract and the validation of an HPLC/diode array detector analytical method, solubility studies were performed to choose the best components for microemulsion formulation. The optimized microemulsion consisted of 2.5 g of triacetin, as the oil phase, 2.5 g of Tween 20 as the surfactant, 2.5 g of labrasol as the cosurfactant, and 5 g of water. The microemulsion was visually checked, characterized by light scattering techniques and morphological observations. The developed formulation appeared transparent, the droplet size was around 40 nm, and the ζ-potential result was negative. The maximum loading content of Salicis cortex extract resulted in 40 mg/mL. Furthermore, storage stability studies and an in vitro digestion assay were performed. The advantages offered by microemulsion were evaluated in vitro using artificial membranes and cells, i.e., parallel artificial membrane permeability assay and a Caco-2 model. Both studies proved that the microemulsion was successful in enhancing the permeation of extract compounds, so it could be useful to ameliorate the bioefficacy of Salicis cortex.

Herbal Compounds with Special Reference to Gastrodin as Potential Therapeutic Agents for Microglia Mediated Neuroinflammation.

BACKGROUND: Activated microglia play a pivotal role neurodegenerative diseases by producing a variety of proinflammatory mediators including tumor necrosis factor-alpha (TNF-α), interleukin- 1beta (IL-1ß) and nitric oxide (NO) that are toxic to neurons and oligodendrocytes. METHODS: In view of the above, suppression of microglia mediated neuroinflammation is deemed a therapeutic strategy for neurodegenerative diseases. Several potential Chinese herbal extracts have been reported to exert neuroprotective effects against neurodegenerative diseases targeting specifically at the activated microglia. In this connection, the phenolic glucoside gastrodin, a main constituent of the Chinese herbal medicine Gastrodia rhizoma, produced widely in the local community exhibits potential neuroprotective effects through suppression of neurotoxic proinflammatory mediators. RESULTS: Here, we first review the roles of activated microglia in different brain diseases. The effects of gastrodin on activated microglia are then considered. We have identified gastrodin as a putative therapeutic agent as it has been found to suppress microglial activation thus ameliorating neuroinflammation. More importantly, gastrodin downregulates the expression of renin angiotensin system (RAS) and production of proinflammatory mediators. Remarkably, gastrodin promotes Sirtuin 3 (Sirt3) up-regulation and nicotinamide adenine dinucleotide phosphate oxidase-2 (NOX-2) down-regulation after ischemichypoxia in activated microglia mediated by AT1 or AT2 receptors which are angiotensin II receptors subtypes, indicating a possible molecular link between RAS and Sirt3 survival genes. CONCLUSION: This review summarizes the beneficial effects of gastrodin acting on activated microglia along with other herbal compounds. Its efficacy in neuroprotection is consistent with some common herbal products in China.

Salicin-7-sulfate: A new salicinoid from willow and implications for herbal medicine.

Willow (Salix sp.) is a historically well-known herbal medicine that provided the lead compound (salicin) for the discovery of aspirin, one of the most successful plant derived drugs in human medicine. During a metabolomics screen of 86 Salix species contained in the UK National Willow Collection, we have discovered, isolated and fully characterised a new natural salicinoid - salicin-7-sulfate. This molecule may have important human pharmacological actions that need to be considered in determining the efficacy and safety of willow herbal medicines.

Gastrodin protects MC3T3-E1 osteoblasts from dexamethasone-induced cellular dysfunction and promotes bone formation via induction of the NRF2 signaling pathway.

Glucocorticoid (GC)-induced osteoporosis (GIO) is one of the most common secondary and iatrogenic forms of osteoporosis. GCs are widely used in clinical therapy and play a key role in the normal regulation of bone remodeling. However, the prolonged and high-dose administration of GCs results in the occurrence of osteoporosis, which is partially due to the dysfunction and apoptosis of osteoblasts and osteocytes. The aim of the present study was to investigate the effects of gastrodin, a natural bioactive compound isolated from the traditional Chinese herbal agent Gastrodia elata, on GC-treated MC3T3­E1 murine osteoblastic cells. MC3T3­E1 cells were exposed to dexamethasone (DEX), with or without gastrodin pretreatment, and cell viability was measured by the cell counting kit-8 (CCK-8) assay. Quantitative polymerase chain reaction analysis was performed to evaluate osteogenic gene expression, and cellular alkaline phosphatase (ALP) activity was measured as well. Alizarin Red staining of calcium deposits was found to reflect the degree of osteoblast maturity. Western blotting was performed to determine the expression of osteogenic and adipogenic differentiation key proteins, as well as nuclear factor-like 2 (NRF2) pathway­related proteins. Annexin V-fluorescein isothiocyanate̸propidium iodide flow cytometric analysis was performed to determine osteoblast apoptosis. JC-1 staining was used to detect the changes of the mitochondrial membrane potential in cells. The results revealed that gastrodin prevented the decrease in cell viability caused by DEX-induced MC3T3­E1 cell dysfunction, and that groups pretreated with gastrodin exhibited higher mRNA levels of osteogenic genes, such as Runx2, osterix, bone morphogenetic protein-2 and osteocalcin. Furthermore, treatment with both DEX and gastrodin was associated with increased ALP activity in MC3T3-E1 cells, as well as more calcium deposits, compared with cells treated with DEX alone. In addition, gastrodin increased osteogenic key marker protein Runx2 while activating NRF2 and downstream effector protein expression. Therefore, gastrodin may have the potential to reduce DEX-induced cell apoptosis and increase the mitochondrial membrane potential against DEX. These results demonstrated that gastrodin was able to prevent and/or delay DEX­induced osteoporosis by improving osteoblast function, and these protective effects were verified in an animal model.

New Alkaloid and Aromatic Glucoside from the Flowers of Cymbidium Lunagrad Eternal Green.

In this paper, we investigated the chemical components of the flowers of Cymbidium Lunagrad Eternal Green for the first time. In the whole post-fertilization, a new alkaloid, named Lunagrad A (1), and a new aromatic glucoside, named Lunagrad B (2), were isolated from the MeOH extract of the flowers of Cymbidium Lunagrad Eternal Green, along with other six known aromatic compounds (3-8) and three flavone glucosides (9-11). These structures were determined on the basis of NMR experiments, as well as chemical evidence.

In vitro inhibitory mechanisms and molecular docking of 1'-S-1'-acetoxychavicol acetate on human cytochrome P450 enzymes.

BACKGROUND: The compound, 1'-S-1'-acetoxychavicol acetate (ACA), isolated from the rhizomes of a Malaysian ethno-medicinal plant, Alpinia conchigera Griff. (Zingiberaceae), was previously shown to have potential in vivo antitumour activities. In the development of a new drug entity, potential interactions of the compound with the cytochrome P450 superfamily metabolizing enzymes need to be ascertain. PURPOSE: The concomitant use of therapeutic drugs may cause potential drug-drug interactions by decreasing or increasing plasma levels of the administered drugs, leading to a suboptimal clinical efficacy or a higher risk of toxicity. Thus, evaluating the inhibitory potential of a new chemical entity, and to clarify the mechanism of inhibition and kinetics in the various CYP enzymes is an important step to predict drug-drug interactions. STUDY DESIGN: This study was designed to assess the potential inhibitory effects of Alpinia conchigera Griff. rhizomes extract and its active constituent, ACA, on nine c-DNA expressed human cytochrome P450s (CYPs) enzymes using fluorescent CYP inhibition assay. METHODS/RESULTS: The half maximal inhibitory concentration (IC50) of Alpinia conchigera Griff. rhizomes extract and ACA was determined for CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2D6, CYP2E1, CYP3A4 and CYP3A5. A. conchigera extract only moderately inhibits on CYP3A4 (IC50 = 6.76 ± 1.88µg/ml) whereas ACA moderately inhibits the activities of CYP1A2 (IC50 = 4.50 ± 0.10µM), CYP2D6 (IC50 = 7.50 ± 0.17µM) and CYP3A4 (IC50 = 9.50 ± 0.57µM) while other isoenzymes are weakly inhibited. In addition, mechanism-based inhibition studies reveal that CYP1A2 and CYP3A4 exhibited non-mechanism based inhibition whereas CYP2D6 showed mechanism-based inhibition. Lineweaver-Burk plots depict that ACA competitively inhibited both CYP1A2 and CYP3A4, with a Ki values of 2.36 ± 0.03 µM and 5.55 ± 0.06µM, respectively, and mixed inhibition towards CYP2D6 with a Ki value of 4.50 ± 0.08µM. Further, molecular docking studies show that ACA is bound to a few key amino acid residues in the active sites of CYP1A2 and CYP3A4, while one amino residue of CYP2D6 through predominantly Pi-Pi interactions. CONCLUSION: Overall, ACA may demonstrate drug-drug interactions when co-administered with other therapeutic drugs that are metabolized by CYP1A2, CYP2D6 or CYP3A4 enzymes. Further in vivo studies, however, are needed to evaluate the clinical significance of these interactions.

Anti-oxidative effects of 4-hydroxybenzyl alcohol in astrocytes confer protective effects in autocrine and paracrine manners.

4-Hydroxybenzyl alcohol (4-HBA) is an important phenolic constituent of Gastrodia elata Blume (GEB), a traditional herbal medicine used in East Asia. Many activities have been reported to underlie the beneficial effects of 4-HBA in the brain, and in particular, its anti-inflammatory, anti-oxidative, and anti-zinc-toxic effects have been implicated in the postischemic brain. Here, the authors investigated the anti-oxidative effect of 4-HBA on astrocytes and sought to identify the underlying molecular mechanisms involved. 4-HBA dose-dependently suppressed H2O2-induced astrocyte cell death. More specifically, pre-incubation of C6 cells (an astrocyte cell line) with 100 µM 4-HBA for 6 hrs increased survival when cells were treated with H2O2 (100 µM, 1 hr) from 54.2±0.7% to 85.9±1.5%. In addition, 4-HBA was found to up-regulate and activate Nrf2, and subsequently, to induce the expressions of several anti-oxidative genes, such as, HO-1, NQO1, and GCLM. Notably, HO-1 was induced by 3.4-fold in 4-HBA-treated C6 cells, and siRNA-mediated HO-1 knockdown demonstrated that Nrf2 activation and HO-1 induction were responsible for the observed cytoprotective effect of 4-HBA. ERK and Akt signaling pathways were activated by 4-HBA in C6 cells, suggesting their involvements in protective effect of 4-HBA. In addition, 4-HBA-conditioned astrocyte culture medium was found to have neuroprotective effects on primary neuronal cultures or fresh C6 cells exposed to oxidative stress, and these effects seemed to be mediated by glial cell line-derived neurotrophic factor (GDNF) and vascular endothelial growth factor (VEGF), which both accumulated in 4-HBA-treated astrocyte culture media. Thus, the 4-HBA-mediated activation of Nrf2 and induction of HO-1 in astrocytes were found to act via autocrine and paracrine mechanisms to confer protective effects. Furthermore, given the pleiotropic effects of 4-HBA with respect to its targeting of various brain cell types and functions, it would appear that 4-HBA has therapeutic potential for the prevention and amelioration of various brain diseases.

Optimization of the Production of 1-Phenylethanol Using Enzymes from Flowers of Tea (Camellia sinensis) Plants.

1-Phenylethanol (1PE) can be used as a fragrance in food flavoring and cosmetic industries and as an intermediate in the pharmaceutical industry. 1PE can be synthesized from acetophenone, and the cost of 1PE is higher than the cost of acetophenone. Therefore, it is important to establish an effective and low-cost approach for producing 1PE. Our previous studies found that tea (Camellia sinensis) flowers, which are an abundant and waste resource, contained enzymes that could transform acetophenone to 1PE. In the present study, we extracted crude enzymes from tea flowers and optimized the production conditions of 1PE using response surface methodology. The optimized conditions were an extraction pH of 7.0, a reaction pH of 5.3, a reaction temperature of 55 °C, a reaction time of 100 min, a coenzyme NADPH concentration of 3.75 µmol/mL in the reaction assay, and a substrate acetophenone concentration of 1.25 µmol/mL in the reaction assay. The results provide essential information for future industrial 1PE production using plant-derived enzymes.

Peniphenylanes A-G from the Deep-Sea-Derived Fungus Penicillium fellutanum HDN14-323.

Seven new 6-methylsaligenin derivatives, including the trimeric peniphenylanes A-B (1-2) and dimeric peniphenylanes C-G (3-7), together with four known biogenetically related compounds (8-11) were discovered from the extract of the deep-sea-derived fungus Penicillium fellutanum HDN14-323. The structures of the new compounds were established through extensive analysis. Their cytotoxic activity against HeLa, HL-60, and HCT-116 cell lines was evaluated, with compound 4 exhibiting the best activity against the HeLa cell line (IC50 = 9.3 µM).

Salicin derivatives from Salix glandulosa and their biological activities.

Two new salicin derivatives, saliglandin (1) and 6'-O-(Z)-p-coumaroylsalicin (2), along with fourteen known analogues (3-16) were isolated from the twigs of Salix glandulosa Seemen. The structures of 1-16 were characterized by the use of NMR methods ((1)H and (13)C NMR, (1)H-(1)H COSY, HSQC and HMBC), chemical hydrolysis, and GC/MS. The full NMR data assignment of the known compounds 6, 13, and 14 are reported for the first time. Isolated compounds were evaluated for their nitric oxide (NO) inhibitory efficacy in lipopolysaccharide (LPS)-activated microglial cell (BV-2). Compounds 2, 5, 8-16 significantly inhibited NO production, compound 11 being the most efficacious (IC50 13.57 µM) respectively. Moreover, compound 16 dramatically increased the nerve growth factor (NGF) production (165.24 ± 11.1%) in C6 glioma cells. Taken together, these results revealed that salicin derivatives from Salix glandulosa might have potent effect as anti-neuroinflammatory agents.

Efficacy and Safety of White Willow Bark (Salix alba) Extracts.

Willow bark extract has been used for thousands of years as an anti-inflammatory, antipyretic, and analgesic. In spite of its long history of use, relatively few human and animal studies have been published that confirm anecdotal observations. A small number of clinical studies have been conducted that support the use of willow bark extracts in chronic lower back and joint pain and osteoarthritis. Willow bark extracts also are widely used in sports performance and weight loss products presumably because of anti-inflammatory and analgesic activities, although no human studies have been published that specifically and directly document beneficial effects. In recent years, various in vitro and animal studies have demonstrated that the anti-inflammatory activity of willow bark extract is associated with down regulation of the inflammatory mediators tumor necrosis factor-α and nuclear factor-kappa B. Although willow bark extracts are generally standardized to salicin, other ingredients in the extracts including other salicylates as well as polyphenols, and flavonoids may also play prominent roles in the therapeutic actions. Adverse effects appear to be minimal as compared to non-steroidal anti-inflammatory drugs including aspirin. The primary cause for concern may relate to allergic reactions in salicylate-sensitive individuals.