Protection against oxidative damage by dihydroflavonols in Engelhardtia chrysolepis

Evaluation of the mineral composition, phytochemical and proximate constituents of three culinary spices in Nigeria: a comparative study

Spices are prolific sources of phytochemicals of pharmaceutical and nutritional importance. They have been employed for centuries in the treatment of various maladies, in cuisines, and as inhibitors of oxidative degradation in foods. On this premise, a comparative assessment of the quantitative mineral composition, phytochemical and proximate constituents of Xylopia aethiopica (fruits), Piper guineense (seeds), and Rhaphiostylis beninensis (roots) was done using standard protocols. Subsequently, methanol extracts of the spices were subjected to Gas Chromatography-Mass Spectrometry (GC-MS) analysis. Mineral analysis of the culinary spices revealed significant differences (p < 0.05) in the spices' magnesium, zinc, iron, selenium, copper, calcium, manganese, molybdenum, potassium, and sodium contents. In the phytochemical analysis, flavonoids, phenols, and alkaloids (4.04%, 2.92%, 2.23%) predominate in X. aethiopica. Similarly, proximate analysis shows a preponderance of carbohydrates (81.24%) and proteins (4.83%) in R. beninensis and P. guineense respectively. However, values for the selenium (0.25 mg/L), saponin (0.23%), and moisture (0.71%) contents for R. beninensis were the lowest among the three spices. Results from the GC-MS analysis revealed the presence of thirteen, twelve, and thirteen phytoconstituents of X. aethiopica, P. guineense, and R. beninensis respectively. Prominent among them are hydrocarbons, acids, and esters with renowned biological attributes such as antioxidant, antimicrobial and anti-inflammatory. These findings indicate that the spices are notable wellsprings of bioactive components and justify their plethoric applications in Nigeria. Therefore, they could serve as lead compounds in the search for natural ingredients for drugs and nutraceuticals formulation.

Natural Compounds That Enhance Motor Function in a Mouse Model of Muscle Fatigue

Musculoskeletal disease can be a serious condition associated with aging that may lead to fractures and a bedridden state due to decreased motor function. In addition to exercise training to increase muscle mass, increasing muscle function with the intake of functional foods is an effective treatment strategy for musculoskeletal disease. Muscle-specific SOD2-deficient mice (muscle-Sod2^-/-) show a severe disturbance in exercise in association with increased mitochondrial reactive oxygen species, as well as mitochondrial dysfunction and muscle damage. In the present study, to develop a therapeutic strategy for musculoskeletal disease, we searched for substances that enhanced motor function among functional compounds by in vivo screening using muscle-Sod2^-/- mice as a muscle fatigue model. We administered 96 compounds, including antioxidants, to muscle-Sod2^-/- mice and assessed their effects on treadmill performance. Among the administered compounds, gossypin, genistein, kaempferol, taxifolin, fumaric acid, β-hydroxy-β-methylbutyrate Ca, and astaxanthin, which are dietary functional food factors, increased forced running time in muscle-Sod2^-/- mice. In addition, troglitazone, tempol, trolox, and MnTE-2-PyP, which are antioxidants, also significantly increased the running ability of muscle-Sod2^-/- mice. These results suggest that the intake of functional foods with antioxidant activity can improve motor function. Muscle-Sod2^-/- mice, as a muscle fatigue model, are suitable for the in vivo screening of functional substances that promote improvements in exercise and muscle performance.

Smilax glabra Roxb.: A Review of Its Traditional Usages, Phytochemical Constituents, Pharmacological Properties, and Clinical Applications

Smilax glabra Roxb. (SGB) is a medicinal plant widely distributed in 17 countries worldwide. It is the primary raw material of the world-famous and best-selling functional food and beneficial tea. SGB was first recorded in Ben Cao Jing Ji Zhu of the Southern and Northern Dynasties (420–589 AD) and was reported for nutritional and medicinal properties for thousands of years. This review searched PubMed, Web of Science, and other databases for relevant literature on SGB species until April 2022. It aims to provide more integrated thinking, detailed awareness, and better knowledge of SGB. More than 200 chemical components have been discovered, including flavonoids, phenolic, phenolic acids, stilbenes, organic acids, phenylpropanoids, and others. Previous studies have demonstrated that SGB and its active ingredients show a wide range of pharmacological effects, including anti-infective, anti-cancer, anti-inflammatory, antioxidant, cardiovascular protection, etc. However, many studies on the biological activity of this plant were mainly based on crude extracts and active ingredients, and there is a lack of clinical studies and toxicity studies to support the development of drug design, development, and therapy. In summary, this review will provide specific and valuable suggestions and guidelines for further research and application of this plant in the medicinal field.

The natural source, physicochemical properties, biological activities and metabolism of astilbin

Astilbin is a dihydroflavanol found in many plants and processed foods. Astilbin possesses multiple health-beneficial bioactivities and has received great attention. Hence, the natural source, physicochemical properties, biological activities and metabolism of astilbin are summarized in the present article. Engelhardia roxburghiana Wall. and Smilax glabra Roxb. are the main resource for astilbin purification because of high content. Because of chemical instability, astilbin amount in foods is dependent on the processing and storage conditions. The degradation of astilbin includes isomerization and decomposition. The interconversion of astilbin and its isomers occurs through a chalcone intermediates, which significantly affects the taste of wine during storage. Many factors such as temperature, pH, metal ions and food additives could affect the chemical stability of astilbin. Astilbin exhibits very novel selective immunosuppressive activity, which is not found in other compounds. The rhamnose moiety of astilbin is essential for this bioactivity. After digestion, astilbin was mainly absorbed and transported in circulatory blood in its intact form, and only one metabolite, 3'-O-methylastilbin, was found. Although having many bioactivities, astilbin faces the challenge of poor bioavailability. Some promising strategies were developed for improving its bioavailability, particularly through fabrication the zein nanoparticles.

Effects of quercetin on ovarian function and regulation of the ovarian PI3K/Akt/FoxO3a signalling pathway and oxidative stress in a rat model of cyclophosphamide-induced premature ovarian failure

To investigate the ability of quercetin to improve ovarian function and inhibit ovarian oxidative stress through the PI3K/Akt/FoxO3a signalling pathway in a rat model of premature ovarian failure (POF), we constructed a POF rat model with cyclophosphamide (CTX) and treated it with quercetin. Haematoxylin and eosin staining (H&E staining) was used to observe the morphological changes of the ovaries. The serum levels of AMH, E2, FSH, SOD, GSH-Px and MDA were determined by enzyme-linked immunosorbent assays. The expression of phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), forkhead box O3a (FoxO3a) and their phosphorylated forms AMH, FSH and their receptors in the ovary were detected by western blots. The mRNA expression of PI3K, Akt, FOXO3a, AMH, FSH and their receptors was detected by qRT-PCR. Our results showed that quercetin could significantly increase the expression of AMH, E2, SOD and GSH-Px, upregulate the protein expression of AMH, FSH and its receptor and decrease the expression ratio of phosphorylated PI3K, Akt, FOXO3a and the unphosphorylated forms. Moreover, quercetin inhibited the mRNA expression of PI3K, Akt and FOXO3a. These results suggest that quercetin can restore ovarian function and inhibit oxidative stress by regulating the PI3K/Akt/FoxO3a signalling pathway.

Taxifolin: A Potential Therapeutic Agent for Cerebral Amyloid Angiopathy

Cerebral amyloid angiopathy (CAA) is characterized by the accumulation of β-amyloid (Aβ) in the walls of cerebral vessels, leading to complications such as intracerebral hemorrhage, convexity subarachnoid hemorrhage and cerebral microinfarcts. Patients with CAA-related intracerebral hemorrhage are more likely to develop dementia and strokes. Several pathological investigations have demonstrated that more than 90% of Alzheimer's disease patients have concomitant CAA, suggesting common pathogenic mechanisms. Potential causes of CAA include impaired Aβ clearance from the brain through the intramural periarterial drainage (IPAD) system. Conversely, CAA causes restriction of IPAD, limiting clearance. Early intervention in CAA could thus prevent Alzheimer's disease progression. Growing evidence has suggested Taxifolin (dihydroquercetin) could be used as an effective therapy for CAA. Taxifolin is a plant flavonoid, widely available as a health supplement product, which has been demonstrated to exhibit anti-oxidative and anti-inflammatory effects, and provide protection against advanced glycation end products and mitochondrial damage. It has also been shown to facilitate disassembly, prevent oligomer formation and increase clearance of Aβ in a mouse model of CAA. Disturbed cerebrovascular reactivity and spatial reference memory impairment in CAA are completely prevented by Taxifolin treatment. These results highlight the need for clinical trials on the efficacy and safety of Taxifolin in patients with CAA.

Taxifolin attenuates the developmental testicular toxicity induced by di-n-butyl phthalate in fetal male rats

Di-n-butyl phthalate (DBP) is widely used in consumer products as a plasticizer. Here, we report a natural product taxifolin that can attenuate developmental and reproductive toxicity of DBP. Pregnant rats were daily gavaged with 500 mg/kg DBP alone or together with taxifolin (10 and 20 mg/kg) from gestational day (GD) 12-21. At GD21, sera and testes of male fetus were collected. DBP significantly lowered serum testosterone level at 500 mg/kg and taxifolin can completely reverse its action. DBP caused abnormal aggregation of fetal Leydig cells and taxifolin can reverse it. DBP down-regulated the expression of the genes of cholesterol side-chain cleavage enzyme (Cyp11a1), 17β-hydroxysteroid dehydrogenase 3 (Hsd17b3), and insulin-like 3 (Insl3) and taxifolin can reverse its action. DBP increased malondialdehyde levels and decreased superoxide dismutase and glutathione peroxidase expression and taxifolin can reverse it. DBP increased incidence of multinucleated gonocytes and taxifolin can prevent it. Moreover, DBP lowered sirtuin 1 (SIRT1)/peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) and phosphorylated AMP-activated protein kinase (pAMPK) signalling and taxifolin antagonized DBP. In conclusion, in utero exposure to DBP caused developmental/reproductive toxicity of male offspring via increasing reactive oxygen species and taxifolin is an effective food component that completely reverses DBP-mediated action.

ASTILBIN: A PROMISING UNEXPLORED COMPOUND WITH MULTIDIMENSIONAL MEDICINAL AND HEALTH BENEFITS

BACKGROUND

Many flavonoids have various beneficial actions like anti-inflammatory, anti-carcinogenic properties and many other clinical conditions. Astilbin is one such flavanoid compound having many physiological as well as pharmacological actions.

PURPOSE

To summarize the important findings from the research conducted using astilbin having significance to its physiological and pharmacological activities as well as the patents filed using astilbin.

STUDY DESIGN

Systematic review and compilation of the collected literature.

METHOD

An extensive investigation of literature was done using several worldwide electronic scientific databases like PUBMED, SCOPUS, Science Direct and Google Scholar etc. All the article available in the English language that used our compound of interest i.e. astilbin, on the basis of inclusion criteria decided were retrieved from these databases, thoroughly reviewed and were summarized.

RESULT

It has been established that astilbin can play a vital in the management of diseases associated with immune system. It also possesses antibacterial, anti-oxidative and hepatoprotective activity.

CONCLUSION

These researches provide evidence that astilbin possesses great potential and thus can be utilized in the management of various disorders, thus establishing itself as a potential candidate for novel drug development. Also, there is still room for research on astilbin like it can be evaluated for anticancer potential, protective effect in various diabetic complications and many more. Overall observations from data suggested that astilbin is a promising compound and proved its efficacy in every preclinical study which is conducted till date. Some of the pharmacological activity is still unexplored. After successful preclinical trials, astilbin can go for further clinical trials.

Quercetin inhibits Mrgprx2-induced pseudo-allergic reaction via PLCγ-IP3R related Ca2+ fluctuations

An allergic reaction is a potentially fatal hypersensitivity response caused by mast cell activation, particularly histamine and lipid mediators. Histamine release caused by reaction to drugs is considered a pseudo-allergic reaction. Quercetin is known for its anti-allergic immune effect. However, at present, its anti-pseudo-allergic effect and its mechanism are less investigated. Therefore, the purpose of this study was to evaluate the anti-pseudo-allergic effect of Quercetin in vivo and to explore the mechanism in vitro. The anti-pseudo-allergic activity of Quercetin was evaluated in vivo using a mouse model, while Quercetin mechanism of action was examined in vitro using HEK293 cells expressing Mrgprx2, a mast cell specific receptor, and LAD2 mast cell line. Our in vivo results showed that Quercetin could attenuate Evans blue leakage in the paws and hind paw thickness in C57BL/6 mice in a dose-dependent manner, and could significantly inhibit serum histamine and chemokines release. In addition, it suppressed calcium mobilization and attenuated the release of histamine and MCP-1 in peritoneal mast cells in a dose-dependent manner. Furthermore, it inhibited the vasodilation due to histamine, the release of eosinophils, and the percentage of degranulated mast cells, indicating that Quercetin antagonized mast cell mediators in vivo, histamine-induced vasodilation and eosinophil release. In vitro results showed that Quercetin reduced pseudo-allergic induced calcium influx, suppressed degranulation and chemokines release in a similar way as dexamethasone (100 μM) (mast cell stabilizer) in LAD2 mast cell line. In addition, Quercetin inhibited Mrgprx2-induced both calcium influx and pseudo-allergic reaction in HEK293 cells expressing Mrgprx2. C48/80, a histamine promoter, and Substance P (a neuropeptide) EC₅₀ was higher when combined with Quercetin compared to the EC₅₀ of these compounds alone, suggesting that Quercetin could inhibit Mrgprx2-induced pseudo-allergic reaction. Furthermore, Quercetin decreased PLCγ-IP3R signaling pathway activation induced by C48/80 in LAD2 mast cell line. In Mrgprx2 knockdown LAD2 cells, the effect of Quercetin (200 μM) reduced C48/80 induced calcium flux and the release of β‑hexosaminidase, histamine, MCP-1 and IL-8 compared with non-atopic control (NC) transfected LAD2 human mast cells, suggesting that Quercetin anti-pseudo-allergic effect was related to Mrgprx2. The docking results showed that Quercetin had a good binding affinity with Mrgprx2 similar to the one of Substance P and C48/80. Therefore, Quercetin inhibited Mrgprx2-induced pseudo-allergic reaction via PLCγ-IP3R associated Ca²⁺ fluctuations. Our results validated Quercetin as an effective small molecule inhibiting Mrgprx2-induced pseudo-allergic reaction via PLCγ-IP3R associated Ca²⁺ fluctuations, thus highlighting a potential candidate to suppress Mrgprx2 induced pseudo-allergic related diseases.

Phytochemicals That Influence Gut Microbiota as Prophylactics and for the Treatment of Obesity and Inflammatory Diseases

Gut microbiota (GM) plays several crucial roles in host physiology and influences several relevant functions. In more than one respect, it can be said that you “feed your microbiota and are fed by it.” GM diversity is affected by diet and influences metabolic and immune functions of the host's physiology. Consequently, an imbalance of GM, or dysbiosis, may be the cause or at least may lead to the progression of various pathologies such as infectious diseases, gastrointestinal cancers, inflammatory bowel disease, and even obesity and diabetes. Therefore, GM is an appropriate target for nutritional interventions to improve health. For this reason, phytochemicals that can influence GM have recently been studied as adjuvants for the treatment of obesity and inflammatory diseases. Phytochemicals include prebiotics and probiotics, as well as several chemical compounds such as polyphenols and derivatives, carotenoids, and thiosulfates. The largest group of these comprises polyphenols, which can be subclassified into four main groups: flavonoids (including eight subgroups), phenolic acids (such as curcumin), stilbenoids (such as resveratrol), and lignans. Consequently, in this review, we will present, organize, and discuss the most recent evidence indicating a relationship between the effects of different phytochemicals on GM that affect obesity and/or inflammation, focusing on the effect of approximately 40 different phytochemical compounds that have been chemically identified and that constitute some natural reservoir, such as potential prophylactics, as candidates for the treatment of obesity and inflammatory diseases.

Taxifolin Activates the Nrf2 Anti-Oxidative Stress Pathway in Mouse Skin Epidermal JB6 P+ Cells through Epigenetic Modifications

Nuclear factor erythroid-2 related factor 2 (Nrf2) is a vital transcription factor that regulates the anti-oxidative defense system. Previous reports suggested that the expression of the Nrf2 gene can be regulated by epigenetic modifications. The potential epigenetic effect of taxifolin (TAX), a potent cancer chemopreventive agent, in skin cancer chemoprotection is unknown. In this study, we investigated how Nrf2 is epigenetically regulated by TAX in JB6 P+ cells. TAX was found to inhibit the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced colony formation of JB6 P+ cells. TAX induced antioxidant response element (ARE)-luciferase activity in HepG2-C8 cells and up-regulated mRNA and protein levels of Nrf2 and its downstream genes heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO1), in JB6 P+ cells. Furthermore, bisulfite genomic sequencing revealed that TAX treatment reduces the methylation level of the first 15 CpGs sites in the Nrf2 promoter. Western blotting showed that TAX inhibits the expression levels of DNA methyltransferase (DNMT) and histone deacetylase (HDAC) proteins. In summary, our results revealed that TAX can induce expression of Nrf2 and its downstream target genes in JB6 P+ cells by CpG demethylation. These finding suggest that TAX may exhibit a skin cancer preventive effect by activating Nrf2 via an epigenetic pathway.

Taxifolin inhibits amyloid-β oligomer formation and fully restores vascular integrity and memory in cerebral amyloid angiopathy

Cerebral amyloid angiopathy (CAA) induces various forms of cerebral infarcts and hemorrhages from vascular amyloid-β accumulation, resulting in acceleration of cognitive impairment, which is currently untreatable. Soluble amyloid-β protein likely impairs cerebrovascular integrity as well as cognitive function in early stage Alzheimer’s disease. Taxifolin, a flavonol with strong anti-oxidative and anti-glycation activities, has been reported to disassemble amyloid-β in vitro but the in vivo relevance remains unknown. Here, we investigated whether taxifolin has therapeutic potential in attenuating CAA, hypothesizing that inhibiting amyloid-β assembly may facilitate its clearance through several elimination pathways. Vehicle- or taxifolin-treated Tg-SwDI mice (commonly used to model CAA) were used in this investigation. Cognitive and cerebrovascular function, as well as the solubility and oligomerization of brain amyloid-β proteins, were investigated. Spatial reference memory was assessed by water maze test. Cerebral blood flow was measured with laser speckle flowmetry and cerebrovascular reactivity evaluated by monitoring cerebral blood flow changes in response to hypercapnia. Significantly reduced cerebrovascular pan-amyloid-β and amyloid-β_1-40 accumulation was found in taxifolin-treated Tg-SwDI mice compared to vehicle-treated counterparts (n = 5). Spatial reference memory was severely impaired in vehicle-treated Tg-SwDI mice but normalized after taxifolin treatment, with scoring similar to wild type mice (n = 10–17). Furthermore, taxifolin completely restored decreased cerebral blood flow and cerebrovascular reactivity in Tg-SwDI mice (n = 4–6). An in vitro thioflavin-T assay showed taxifolin treatment resulted in efficient inhibition of amyloid-β_1-40 assembly. In addition, a filter trap assay and ELISA showed Tg-SwDI mouse brain homogenates exhibited significantly reduced levels of amyloid-β oligomers in vivo after taxifolin treatment (n = 4–5), suggesting the effects of taxifolin on CAA are attributable to the inhibition of amyloid-β oligomer formation. In conclusion, taxifolin prevents amyloid-β oligomer assembly and fully sustains cognitive and cerebrovascular function in a CAA model mice. Taxifolin thus appears a promising therapeutic approach for CAA.

Sarcandra glabra (Caoshanhu) protects mesenchymal stem cells from oxidative stress: a bioevaluation and mechanistic chemistry

BACKGROUND

Sarcandra glabra (Caoshanhu) is a traditional Chinese herbal medicine used for treating various oxidative-stressed diseases. The present work evaluated its protective effect on mesenchymal stem cells (MSCs) from oxidative stress and then discussed possible mechanisms underlying this observation.

METHODS

Ethanolic extract of S. glabra (ESG) was investigated by chemical methods for its content of total phenolics, rosmarinic acid, and astilbin. ESG, along with rosmarinic acid and astilbin, was investigated for the effect on the viability of Fenton-treated MSCs using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl (MTT) assay. The observed cell protective effect was further explored by mechanistic chemistry using various antioxidant assays, including DNA protection, •OH-scavenging, •O2--scavenging, FRAP (ferric ion reducing antioxidant power), ABTS+•-scavenging, DPPH•-scavenging, and Fe2+-chelating assays.

RESULTS

Analysis of ESG revealed a content of 46.31 ± 0.56 mg quercetin/g total phenolics, 0.78 ± 0.01 % rosmarinic acid, and 3.37 ± 0.01 % astilbin. Results from the MTT assay revealed that three compounds (rosmarinic acid>astilbin>ESG) could effectively increase the survival of Fenton-treated MSCs. Similarly, in •O2--scavenging, DPPH•-scavenging, and Fe2+-chelating assays, rosmarinic acid exhibited more activity than astilbin; while in FRAP, ABTS+•-scavenging assays, astilbin was stronger than rosmarinic acid.

CONCLUSION

S. glabra can prevent MSCs from •OH-induced oxidative stress. Such protective effect can be attributed to its antioxidant ability and the presence of two kinds of phytophenols, i.e. caffeoyl derivatives and flavonoids. As the respective representatives of caffeoyl derivatives and flavonoids, rosmarinic acid and astilbin may exert the antioxidant action via direct ROS-scavenging and indirect ROS-scavenging (i.e. Fe2+-chelating). The direct ROS-scavenging ability involves hydrogen atom transfer (HAT) and/or electron transfer (ET) pathway. Astilbin engages the latter pathway more, which can be attributed to the larger planar conjugation in A/C fused rings. Rosmarinic acid, on the other hand, shows more HAT and Fe2+-chelating potential, which may be due to rosmarinic acid bearing one more catechol moiety whereas astilbin has steric-hindrance from 3-α-L-rhamnose and an H-bonding between 4,5 sites. The antioxidant features of rosmarinic acid can be generalized to other caffeoyl derivatives, while that of astilbin cannot be generalized to other flavonoids because of the difference in chemical structures.

Astilbin alleviates LPS-induced ARDS by suppressing MAPK signaling pathway and protecting pulmonary endothelial glycocalyx

Acute respiratory distress syndrome (ARDS) is a devastating disorder that is characterized by increased vascular endothelial permeability and inflammation. Unfortunately, no effective treatment beyond supportive care is available for ARDS. Astilbin, a flavonoid compound isolated from Rhizoma Smilacis Glabrae, has been used for anti-hepatic, anti-arthritic, and anti-renal injury treatments. This study examined the effects of Astilbin on pulmonary inflammatory activation and endothelial cell barrier dysfunction caused by Gram-negative bacterial endotoxin lipopolysaccharide (LPS). Endothelial cells from human umbilical veins or male Kunming mice were pretreated with Astilbin 24h before LPS stimulation. Results showed that Astilbin significantly attenuated the pulmonary histopathological changes and neutrophil infiltration 6h after the LPS challenge. Astilbin suppressed the activities of myeloperoxidase and malondialdehyde, as well as the expression of tumor necrosis factor-α and interleukin-6 in vivo and in vitro. As indices of pulmonary edema, lung wet-to-dry weight ratios, were markedly decreased by Astilbin pretreatment. Western blot analysis also showed that Astilbin inhibited LPS-induced activation of mitogen-activated protein kinase (MAPK) pathways in lung tissues. Furthermore, Astilbin significantly inhibited the activity of heparanase and reduced the production of heparan sulfate in the blood serum as determined by ELISA. These findings indicated that Astilbin can alleviate LPS-induced ARDS, which potentially contributed to the suppression of MAPK pathway activation and the degradation of endothelial glycocalyx.

Assessment of Pradosia huberi effects on the reproductive system of male rats

Pradosia huberi is a species found in the Amazon region and used as an antiulcerogenic and gastroprotective agent; however, phytochemical analysis has revealed the presence of compounds with potential toxic effects on the reproductive system. For the evaluation of the toxicity of P. huberi on male fertility, male Wistar rats were divided into four groups: one control (distilled water p.o.) and three treated (hydroalcoholic extract of the stem bark of P. Huberi (PH-HAE) at doses of 1.22, 6.1, and 30.5 mg/kg p.o.) once daily, for 63 days. In the last week of treatment (from the 57th to the 63rd day), the rats were mated with untreated virgin females (n = 30/group) and were killed on day 64. To investigate the toxic potential of PH-HAE on the reproductive system of rats the following parameters were evaluated: sperm production, genotoxicity, and general development. The production of gametes and their morphology did not differ between control and treated groups. Treatment with PH-HAE did not result in fewer vaginal plugs formed, indicating that the ability to mate was not impaired, but caused an increase of 14.3 and 10.8% in the preimplantation loss index, a reduction of 14.3 and 10.8% in the implantation index, and a reduction of 5.6 and 8.2% in the postimplantation loss index of female rats mated with rats treated with 6.1 and 30.5 mg/kg, respectively, indicating a possible toxic action of PH-HAE on the reproductive system of rats.

Decrease of Functional Activated T and B Cells and Treatment of Glomerulonephitis in Lupus-Prone Mice Using a Natural Flavonoid Astilbin

Treatment of systemic lupus erythematosus (SLE), a chronic inflammatory disease, involves the long-term use of immunosuppressive agents with significant side effects. New therapeutic approaches are being explored to find better treatment possibilities. In this study, age-matched female MRL/lpr mice were treated orally with a natural flavonoid astilbin. Astilbin administration started either at week 8 or week 12 of age though week 20. In the early treatment regimen, the treatment with astilbin reduced splenomegaly / lymphomegaly, autoantibody production and ameliorated lupus nephitis. Several serum cytokines were significantly decreased upon treatment including IFN-g, IL-17A, IL-1b, TNF-a and IL-6. Both spleen CD44^hiCD62L^lo activated T cells and CD138⁺B220^- plasma cells greatly declined. Furthermore, astilbin treatment resulted in decreased mitochondrial membrane potential in activated T cells and downregulated expression of the co-stimulatory molecules CD80 and CD86 on LPS stimulated B cells. Similar but less profound effectiveness was observed in the mice with established disease in the late treatment regimen. These results indicate that the natural product astilbin can mitigate disease development in lupus-prone mice by decreasing functional activated T and B cells.

Inhibition of Rat 5α-Reductase Activity and Testosterone-Induced Sebum Synthesis in Hamster Sebocytes by an Extract of Quercus acutissima Cortex

Objective. Bokusoku (BK) is an extract from the Quercus cortex used in folk medicine for treatment of skin disorders and convergence, and is present in jumihaidokuto, a traditional Japanese medicine that is prescribed for purulent skin diseases like acne vulgaris. The excess of sebum production induced by androgen is involved in the development of acne. Our aim is to examine whether BK and its constituents inhibit testosterone metabolism and testosterone-induced sebum synthesis. Methods. Measurements of 5α-reductase activity and lipogenesis were performed using rat liver microsomes and hamster sebocytes, respectively. Results. BK dose-dependently reduced the conversion of testosterone to a more active androgen, dihydrotestosterone in a 5α-reductase enzymatic reaction. Twenty polyphenols in BK categorized as gallotannin, ellagitannin, and flavonoid were identified by LC-MS/MS. Nine polyphenols with gallate group, tetragalloyl glucose, pentagalloyl glucose, eugeniin, 1-desgalloyl eugeniin, casuarinin, castalagin, stenophyllanin C, (−)-epicatechin gallate, and (−)-epigallocatechin gallate, inhibited testosterone metabolism. In particular, pentagalloyl glucose showed the strongest activity. BK and pentagalloyl glucose suppressed testosterone-induced lipogenesis, whereas they weakly inhibited the lipogenic action of insulin. Conclusions. BK inhibited androgen-related pathogenesis of acne, testosterone conversion, and sebum synthesis, partially through 5α-reductase inhibition, and has potential to be a useful agent in the therapeutic strategy of acne.

Qualitative and quantitative analysis of Rhizoma Smilacis glabrae by ultra high performance liquid chromatography coupled with LTQ OrbitrapXL hybrid mass spectrometry

Rhizoma Smilacis glabrae, a traditional Chinese medicine (TCM) as well as a functional food, has been commonly used for detoxification treatments, relieving dampness and as a diuretic. In order to quickly define the chemical profiles and control the quality of Smilacis glabrae, ultra high performance liquid chromatography coupled with electrospray ionization hybrid linear trap quadrupole orbitrap mass spectrometry (UHPLC-ESI/LTQ-Orbitrap-MS) was applied for simultaneous identification and quantification of its bioactive constituents. A total of 56 compounds, including six new compounds, were identified or tentatively deduced on the basis of their retention behaviors, mass spectra, or by comparison with reference substances and literature data. The identified compounds belonged to flavonoids, phenolic acids and phenylpropanoid glycosides. In addition, an optimized UHPLC-ESI/LTQ-Orbitrap-MS method was established for quantitative determination of six marker compounds from five batches. The validation of the method, including linearity, sensitivity (LOQ), precision, repeatability and spike recoveries, was carried out and demonstrated to be satisfied the requirements of quantitative analysis. The results suggested that the established method would be a powerful and reliable analytical tool for the characterization of multi-constituent in complex chemical system and quality control of TCM.

Induction of TGF-β and IL-10 production in dendritic cells using astilbin to inhibit dextran sulfate sodium-induced colitis

Astilbin, a major bioactive compound from Rhizoma smilacis glabrae, has been reported to possess anti-inflammatory properties. Our study first evaluated astilbin on dextran sulfate sodium (DSS)-induced acute colitis in mice. By intraperitoneal injection of astilbin, the severity of colitis was attenuated, and the serum levels of IL-10 and TGF-β were increased. Using flow cytometry, a higher number of IL-10(+) dendritic cells (DCs) and TGF-β(+) DCs and a lower number of CD86(+) DCs, IL-12 p40(+) DCs, and IL-1β(+) DCs were detected in the spleen of mice with colitis after astilbin treatment. The administration of astilbin also resulted in the upregulation of CD103(+) expression in colonic DCs. In a coculture system, murine bone marrow-derived DCs pretreated with astilbin resulted in an enhanced production of CD4(+)CD25(+)Foxp3(+) T cells. The results of this study show that astilbin could be a candidate drug for inflammatory bowel disease by mediating the regulatory functions of DCs.

Genome-based analysis of the transcriptome from mature chickpea root nodules

Symbiotic nitrogen fixation (SNF) in root nodules of grain legumes such as chickpea is a highly complex process that drastically affects the gene expression patterns of both the prokaryotic as well as eukaryotic interacting cells. A successfully established symbiotic relationship requires mutual signaling mechanisms and a continuous adaptation of the metabolism of the involved cells to varying environmental conditions. Although some of these processes are well understood today many of the molecular mechanisms underlying SNF, especially in chickpea, remain unclear. Here, we reannotated our previously published transcriptome data generated by deepSuperSAGE (Serial Analysis of Gene Expression) to the recently published draft genome of chickpea to assess the root- and nodule-specific transcriptomes of the eukaryotic host cells. The identified gene expression patterns comprise up to 71 significantly differentially expressed genes and the expression of twenty of these was validated by quantitative real-time PCR with the tissues from five independent biological replicates. Many of the differentially expressed transcripts were found to encode proteins implicated in sugar metabolism, antioxidant defense as well as biotic and abiotic stress responses of the host cells, and some of them were already known to contribute to SNF in other legumes. The differentially expressed genes identified in this study represent candidates that can be used for further characterization of the complex molecular mechanisms underlying SNF in chickpea.

Taxifolin suppresses UV-induced skin carcinogenesis by targeting EGFR and PI3K

Skin cancer is one of the most commonly diagnosed cancers in the United States. Taxifolin reportedly exerts multiple biologic effects, but the molecular mechanisms and direct target(s) of taxifolin in skin cancer chemoprevention are still unknown. In silico computer screening and kinase profiling results suggest that the EGF receptor (EGFR), phosphoinositide 3-kinase (PI3K), and Src are potential targets for taxifolin. Pull-down assay results showed that EGFR, PI3K, and Src directly interacted with taxifolin in vitro, whereas taxifolin bound to EGFR and PI3K, but not to Src in cells. ATP competition and in vitro kinase assay data revealed that taxifolin interacted with EGFR and PI3K at the ATP-binding pocket and inhibited their kinase activities. Western blot analysis showed that taxifolin suppressed UVB-induced phosphorylation of EGFR and Akt, and subsequently suppressed their signaling pathways in JB6 P+ mouse skin epidermal cells. Expression levels and promoter activity of COX-2 and prostaglandin E(2) (PGE(2)) generation induced by UVB were also attenuated by taxifolin. The effect of taxifolin on UVB-induced signaling pathways and PGE(2) generation was reduced in EGFR knockout murine embryonic fibroblasts (MEF) compared with EGFR wild-type MEFs. Taxifolin also inhibited EGF-induced cell transformation. Importantly, topical treatment of taxifolin to the dorsal skin significantly suppressed tumor incidence, volume, and multiplicity in a solar UV (SUV)-induced skin carcinogenesis mouse model. Further analysis showed that the taxifolin-treated group had a substantial reduction in SUV-induced phosphorylation of EGFR and Akt in mouse skin. These results suggest that taxifolin exerts chemopreventive activity against UV-induced skin carcinogenesis by targeting EGFR and PI3K.

Dihydroquercetin: More than just an impurity?

Dihydroquercetin (taxifolin) is a potent flavonoid found in onions, French maritime bark, milk thistle, tamarind seeds and commercially available semi-synthetic monoHER marketed as Venoruton. This review focuses on the therapeutic promise of dihydroquercetin in major disease states such as cancer, cardiovascular disease and liver disease by reviewing the proposed mechanism(s) of action, including the activation of the antioxidant response element (ARE) and detoxifying phase II enzymes, inhibition of cytochrome P(450) and fatty acid synthase in carcinogenesis. TNF-alpha and NF-ĸB dependent transcription in hepatitis C infections, the scavenging effect of myeloperoxidase (MPO) derived reactive nitrogen species and subsequent effects on cholesterol biosynthesis as well as the effects on apob/apoA-I, HMG-CoA reductase and apoptosis are reviewed. The stereochemistry and pro-oxidant effect of dihydroquercetin are also considered. Although the majority of research on dihydroquercetin to date has focused on the identification of molecular targets in vitro, this review will bring together evidence of the potency and mode of action of dihydroquercetin and will propose a role for the therapeutic potential of flavonoid antioxidants.

Isolation and characterization of two flavonoids, engeletin and astilbin, from the leaves of Engelhardia roxburghiana and their potential anti-inflammatory properties

Engeletin, a flavonoid compound, was isolated from the leaves of Engelhardia roxburghiana for the first time, along with astilbin, another flavonoid. The chemical structures of engeletin and astilbin were confirmed by (1)H and (13)C nuclear magnetic resonance (NMR) and mass spectrometry (MS) spectra, and their anti-inflammatory activities were studied in lipopolysaccharide (LPS)-stimulated mouse J774A.1 macrophage cells. LPS induced the inflammatory state in macrophage cells and increased mRNA expressions of pro-inflammatory cytokines. Engeletin and astilbin exhibited remarkable inhibitory effects on interleukin (IL)-1β and IL-6 mRNA expression. Significant inhibition of LPS-mediated mRNA expressions were also seen in LPS binding toll-like receptor (TLR)-4, pro-inflammatory cytokine tumor necrosis factor (TNF)-α, IL-10, chemoattractant monocyte chemotactic protein (MCP)-1, and cyclooxygenase (COX)-2 genes. The reduced expression of these cytokines may alleviate immune response and reduce inflammatory activation, indicating that engeletin and astilbin may serve as potential anti-inflammatory agents.

Annonaceae: bio-resource for tomorrow's drug discovery

One of the rich sources of lead compounds is the Angiosperms. Many of these lead compounds are useful medicines naturally, whereas others have been used as the basis for synthetic agents. These are potent and effective compounds, which have been obtained from plants, including anti-cancer (cytotoxic) agents, anti-malaria (anti-protozoal) agents, and anti-bacterial agents. Today, the number of plant families that have been extensively studied is relatively very few and the vast majorities have not been studied at all. The Annonaceae is the largest family in the order Magnoliales. It includes tropical trees, bushes, and climbers, which are often used as traditional remedies in Southeast Asia. Members of the Annonaceae have the particularity to elaborate a broad spectrum of natural products that have displayed anti-bacterial, anti-fungal, and anti-protozoal effects and have been used for the treatment of medical conditions, such as skin diseases, intestinal worms, inflammation of the eyes, HIV, and cancer. These special effects and the vast range of variation in potent compounds make the Annonaceae unique from other similar families in the Magnoliales and the Angiosperms in general. This paper attempts to summarize some important information and discusses a series of hypotheses about the effects of Annonaceae compounds.

Transcriptomic changes induced by acute ozone in resistant and sensitive Medicago truncatula accessions

BACKGROUND

Tropospheric ozone, the most abundant air pollutant is detrimental to plant and animal health including humans. In sensitive plant species even a few hours of exposure to this potent oxidant (200-300 nL. L-1) leads to severe oxidative stress that manifests as visible cell death. In resistant plants usually no visible symptoms are observed on exposure to similar ozone concentrations. Naturally occurring variability to acute ozone in plants provides a valuable resource for examining molecular basis of the differences in responses to ozone. From our earlier study in Medicago truncatula, we have identified cultivar Jemalong is ozone sensitive and PI 464815 (JE154) is an ozone-resistant accession. Analyses of transcriptome changes in ozone-sensitive and resistant accession will provide important clues for understanding the molecular changes governing the plant responses to ozone.

RESULTS

Acute ozone treatment (300 nL L-1 for six hours) led to a reactive oxygen species (ROS) burst in sensitive Jemalong six hours post-fumigation. In resistant JE154 increase in ROS levels was much reduced compared to Jemalong. Based on the results of ROS profiling, time points for microarray analysis were one hour into the ozone treatment, end of treatment and onset of an ozone-induced ROS burst at 12 hours. Replicated temporal transcriptome analysis in these two accessions using 17 K oligonucleotide arrays revealed more than 2000 genes were differentially expressed. Significantly enriched gene ontologies (GOs) were identified using the Cluster Enrichment analysis program. A striking finding was the alacrity of JE154 in altering its gene expression patterns in response to ozone, in stark contrast to delayed transcriptional response of Jemalong. GOs involved in signaling, hormonal pathways, antioxidants and secondary metabolism were altered in both accessions. However, the repertoire of genes responding in each of these categories was different between the two accessions. Real-time PCR analysis confirmed the differential expression patterns of a subset of these genes.

CONCLUSION

This study provided a cogent view of the unique and shared transcriptional responses in an ozone-resistant and sensitive accession that exemplifies the complexity of oxidative signaling in plants. Based on this study, and supporting literature in Arabidopsis we speculate that plants sensitive to acute ozone are impaired in perception of the initial signals generated by the action of this oxidant. This in turn leads to a delayed transcriptional response in the ozone sensitive plants. In resistant plants rapid and sustained activation of several signaling pathways enables the deployment of multiple mechanisms for minimizing the toxicity effect of this reactive molecule.

Broad substrate Cytochrome P450 monooxygenase activity in the cells of Aspergillus terreus MTCC 6324

Cytochrome P450 (CYP) monooxygenase activities with different category of substrates namely, alkanes, alkane derivatives, alcohols, aromatic compounds, organic solvents, and steroids were detected in the cells of Aspergillus terreus. High CYP specific activity was observed when methanol (5.6+/-0.017 U mg(-1)), acetone (7.76+/-0.02 U mg(-1)), dimethylsulphoxide (DMSO) (9.70+/-0.005 U mg(-1)), n-hexadecane (4.39+/-0.02 U mg(-1)), or n-octadecane (4.23+/-0.01 U mg(-1)) were used as substrates. Significant CYP specific activity was also detected when naphthalene (3.80+/-0.002 U mg(-1)) was used as substrate. The CYP catalysis of n-hexadecane had followed both terminal and sub terminal oxidations. The activity was localized in the cytosol of n-hexadecane grown cells, while, it was apparently distributed in light mitochondrial fraction and microsomal fraction of glucose grown cells. The substrate specificities of CYP present in all the locations were similar irrespective of the substrates used for the growth. Heme staining of the microsomal fraction containing CYP and other proteins in SDS-PAGE showed single heme protein band with corresponding molecular weight of 110 kDa.