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Sample records for 5alpha-reductase inhibitory activity

  1. The 5 alpha-reductase inhibitory components from heartwood of Artocarpus incisus: structure-activity investigations.

    PubMed

    Shimizu, K; Fukuda, M; Kondo, R; Sakai, K

    2000-02-01

    The methanol extract of heartwood of Artocarpus incisus showed potent 5 alpha-reductase inhibitory activity. We investigated the 5 alpha-reductase inhibitory effects of nine compounds isolated from A. incisus. Chlorophorin (IC50 = 37 microM) and artocarpin (IC50 = 85 microM) showed more potent inhibitory effects than did alpha-linolenic acid, which is known as a naturally occurring potent inhibitor. Structure-activity investigations suggested that the presence of an isoprene substituent (prenyl and geranyl) would enhance 5 alpha-reductase inhibitory effects.

  2. Testosterone 5alpha-reductase inhibitory active constituents of Piper nigrum leaf.

    PubMed

    Hirata, Noriko; Tokunaga, Masashi; Naruto, Shunsuke; Iinuma, Munekazu; Matsuda, Hideaki

    2007-12-01

    Previously we reported that Piper nigrum leaf extract showed a potent stimulation effect on melanogenesis and that (-)-cubebin (1) and (-)-3,4-dimethoxy-3,4-desmethylenedioxycubebin (2) were isolated as active constituents. As a part of our continuous studies on Piper species for the development of cosmetic hair-care agents, testosterone 5alpha-reductase inhibitory activity of aqueous ethanolic extracts obtained from several different parts of six Piper species, namely Piper nigrum, P. methysticum, P. betle, P. kadsura, P. longum, and P. cubeba, were examined. Among them, the extracts of P. nigrum leaf, P. nigrum fruit and P. cubeba fruit showed potent inhibitory activity. Activity-guided fractionation of P. nigrum leaf extract led to the isolation of 1 and 2. Fruits of P. cubeba contain 1 as a major lignan, thus inhibitory activity of the fruit may be attributable to 1. As a result of further assay on other known constituents of the cited Piper species, it was found that piperine, a major alkaloid amide of P. nigrum fruit, showed potent inhibitory activity, thus a part of the inhibitory activity of P. nigrum fruit may depend on piperine. The 5alpha-reductase inhibitory activities of 1 and piperine were found for the first time. In addition, the P. nigrum leaf extract showed in vivo anti-androgenic activity using the hair regrowth assay in testosterone sensitive male C57Black/6CrSlc strain mice.

  3. 5 alpha-reductase and aromatase inhibitory constituents from Brassica rapa L. pollen.

    PubMed

    Li, Yong-Hui; Yang, Yi-Fang; Li, Kun; Jin, Li-Li; Yang, Nian-Yun; Kong, De-Yun

    2009-04-01

    In the screening of biologically active constituents from Brassica rapa pollen, the supercritical CO(2) fluid extract (SFE-CO(2)) showed potent 5 alpha-reductase and aromatase inhibiting activity. The SFE-CO(2) extract was separated by various chromatographic methods to give two new phytosterol derivatives, 24-methylenecholesterol linolenate (1) and cycloeucalenol linolenate (2), as well as eight known compounds, 24-methylenecholesterol palmitate (3), cycloeucalenol (4), pollinastanol (5), 24-methylenecholesterol (6), linolenic acid (7), palmitic acid (8), monolinolein (9) and monopalmitin (10), compounds 7 and 9 showed potent 5 alpha-reductase inhibitory activity; compounds 1-6 and 10 showed potent aromatase inhibitory activity.

  4. Antihormonal activities of 5 alpha-reductase and aromatase inhibitors.

    PubMed

    Zoppi, S; Cocconi, M; Lechuga, M J; Messi, E; Zanisi, M; Motta, M

    1988-10-01

    The problem of developing androgen antagonists has been tackled so far only by synthesizing steroids able to displace testosterone and other androgens from their specific receptor sites. The observation that testosterone has to be converted intracellularly either to 5 alpha-reduced metabolites (DHT, 3 alpha-diol, etc.) or to estrogens, in order to become fully active on androgen-dependent structures (both central and peripheral), has opened the possibility of creating molecules which prevent these conversions, and which could then block the actions of testosterone. The availability of these new compounds has allowed a better understanding of the selective physiological role of each of the metabolites of testosterone, and to provide the basis for the development of new hormone antagonists to be used in those clinical conditions for which an inhibition of the actions of testosterone is foreseen. The usefulness of these enzyme inhibitors is underlined by some examples described in this paper. The results obtained may permit the formulation of the following conclusions: (1) The conversion of testosterone to its 5 alpha-reduced metabolites occurring in the neuroendocrine structures may represent an essential step for the appearance of the inhibitory feedback effect testosterone exerts on LH secretion; (2) Testosterone exhibits its negative feedback effect on FSH secretion as such and not following the local aromatization to estrogens; (3) Testosterone exerts its effect on the intrahypothalamic stores of LHRH acting as such and not following its local conversion either to 5 alpha-reduced metabolites or to estrogenic molecules; (4) Some of the new enzyme inhibitors (e.g. 4-OH-A) may represent an interesting tool for the treatment and/or the prevention of BPH and possibly of other androgen-dependent diseases (prostate carcinoma, acne etc.), as shown by their ability to prevent the in vitro conversion of testosterone to its 5 alpha-reduced metabolites both in the normal

  5. 5-alpha reductase inhibitors in patients on active surveillance: do the benefits outweigh the risk?

    PubMed

    Al Edwan, Ghazi; Fleshner, Neil

    2013-06-01

    Prostate cancer (PCa) is a slow, progressive disease. Prostate specific antigen testing, screening, and aggressive case identification has made PCa the most frequently diagnosed cancer. Concerns regarding overdiagnosis and overtreatment flourish on a large scale. In order to avoid overtreatment for those in whom therapeutic intervention is not required, active surveillance for eligible patients with the use of 5-alpha reductase can be considered a safe and a promising approach to delay the progression of the disease with minimal side effects. PMID:23579402

  6. Activity of type 1 5 alpha-reductase is greater in the follicular infrainfundibulum compared with the epidermis.

    PubMed

    Thiboutot, D M; Knaggs, H; Gilliland, K; Hagari, S

    1997-02-01

    The enzyme 5 alpha-reductase converts testosterone (T) to dihydrotestosterone (DHT). Although this enzyme has been localized to various regions of the pilosebaceous unit, its activity has not been studied in the follicular portion of either vellus or sebaceous follicles. The goal of our study was to determine the relative activities of 5 alpha-reductase within various regions of these follicles with particular emphasis on the infrainfundibulum. A finding of increased 5 alpha-reductase activity in upper follicles compared to epidermis might support the hypothesis that increased follicular production of DHT is involved in the hyperkeratinization observed in this region of the follicle in acne vulgaris. 5 alpha-reductase activity was determined at pH 5 (optimal for the type 2 isozyme) and pH 7 (optimal for the type 1 isozyme) in isolated infrainfundibular segments from sebaceous and vellus follicles, homogenized epidermis from various anatomical areas and in microdissected segments of the pilosebaceous unit from breast skin of normal subjects. Enzyme activity was also determined at pH 7 in cultured infrainfundibular keratinocytes and in interfollicular epidermal keratinocytes. Homogenates of infrainfundibular segments demonstrated significantly greater activity at pH 7 compared to pH 5 (P < 0.001), confirming activity of the type 1 5 alpha-reductase in this region. Activity of 5 alpha-reductase was much lower in homogenized epidermis and did not demonstrate a clear pH preference. Keratinocytes cultured from the infrainfundibulum demonstrated significantly greater 5 alpha-reductase activity compared to keratinocytes from interfollicular epidermis (P = 0.04). In the dissected segments of pilosebaceous units from breast skin, 5 alpha-reductase activity was greatest in the sebaceous gland followed by the sebaceous duct, infrainfundibulum, whole skin and epidermis. These data indicate that 5 alpha-reductase activity varies within regions of the pilosebaceous unit and

  7. Proscar (Finasteride) inhibits 5 alpha-reductase activity in the ovaries and testes of Lytechinus variegatus Lamarck (Echinodermata: Echinoidea).

    PubMed

    Wasson, K M; Watts, S A

    1998-10-01

    Recent investigations into the steroid metabolic pathway in the echinoid Lytechinus variegatus demonstrated the capacity of the gonads to convert androstenedione, the classical mammalian precursor to bioactive androgens, into testosterone and a variety of 5 alpha-reduced androgens including 5 alpha-androstane-3 beta, 17 beta-diol and 5 alpha-androstane-3 alpha, 17 beta-diol. The synthesis of these steroids, which requires 5 alpha-reductase activity, varies with sex and reproductive state in L. variegatus, suggesting that these steroids may be involved in reproductive processes. The classical method of castration followed by steroid replacement therapy to determine the biological role of steroids in the gonads of higher vertebrates is not possible in echinoids. Therefore, this study was designed to determine the efficacy of finasteride, a selective 5 alpha-reductase inhibitor in the mammalian prostate gland, on 5 alpha-reductase activity in the gonads of L. variegatus. Finasteride inhibits echinoid 5 alpha-reductase in a dose-dependent manner with IC50 approximately 2.7 microM for both ovaries and testes. These echinoid IC50s are significantly higher than those reported for humans and rats. In addition, oral administration of finasteride to the echinoids appeared to inhibit 5 alpha-reductase with no apparent stress (no spine loss) to the animals. These data suggest that finasteride may be used to selectively and chemically ablate 5 alpha-reduced androgen synthesis in the gonads of L. variegatus. PMID:9827060

  8. Inhibition of type 1 and type 2 5alpha-reductase activity by free fatty acids, active ingredients of Permixon.

    PubMed

    Raynaud, Jean Pierre; Cousse, Henri; Martin, Pierre Marie

    2002-10-01

    In different cell systems, the lipido-sterolic extract of Serenoa repens (LSESr, Permixon inhibits both type 1 and type 2 5alpha-reductase activity (5alphaR1 and 5alphaR2). LSESr is mainly constituted of fatty acids (90+/-5%) essentially as free fatty acids (80%). Among these free fatty acids, the main components are oleic and lauric acids which represent 65% and linoleic and myristic acids 15%. To evaluate the inhibitory effect of the different components of LSESr on 5alphaR1 or 5alphaR2 activity, the corresponding type 1 and type 2 human genes have been cloned and expressed in the baculovirus-directed insect cell expression system Sf9. The cells were incubated at pH 5.5 (5alphaR2) and pH 7.4 (5alphaR1) with 1 or 3nM testosterone in presence or absence of various concentrations of LSESr or of its different components. Dihydrotestosterone formation was measured with an automatic system combining HPLC and an on-line radiodetector. The inhibition of 5alphaR1 and 5alphaR2 activity was only observed with free fatty acids: esterified fatty acids, alcohols as well as sterols assayed were inactive. A specificity of the fatty acids in 5alphaR1 or 5alphaR2 inhibition has been found. Long unsaturated chains (oleic and linolenic) were active (IC(50)=4+/-2 and 13+/-3 microg/ml, respectively) on 5alphaR1 but to a much lesser extent (IC(50)>100 and 35+/-21 microg/ml, respectively) on 5alphaR2. Palmitic and stearic acids were inactive on the two isoforms. Lauric acid was active on 5alphaR1 (IC(50)=17+/-3 microg/ml) and 5alphaR2 (IC(50)=19+/-9 microg/ml). The inhibitory activity of myristic acid was evaluated on 5alphaR2 only and found active on this isoform (IC(50)=4+/-2 microg/ml). The dual inhibitory activity of LSESr on 5alpha-reductase type 1 and type 2 can be attributed to its high content in free fatty acids.

  9. Determination of oenothein B as the active 5-alpha-reductase-inhibiting principle of the folk medicine Epilobium parviflorum.

    PubMed

    Lesuisse, D; Berjonneau, J; Ciot, C; Devaux, P; Doucet, B; Gourvest, J F; Khemis, B; Lang, C; Legrand, R; Lowinski, M; Maquin, P; Parent, A; Schoot, B; Teutsch, G

    1996-05-01

    Several extracts from Epilobium parviflorum, a plant used in Central Europe for the treatment of prostate disorders, were evaluated in a biochemical assay with 5-alpha-reductase. The aqueous extract displaying inhibition of the enzyme was analyzed, the fraction responsible for this activity was purified, and the active compound identified as a macrocyclic tannin, oenothein B (1). PMID:8778238

  10. Induction of a deficiency of steroid delta 4-5 alpha-reductase activity in liver by a porphyrinogenic drug.

    PubMed Central

    Kappas, A; Bradlow, H L; Bickers, D R; Alvares, A P

    1977-01-01

    The hepatic enzymes that catalyze drug oxidations and the reductive metabolism of steroid hormones to 5alpha-derivatives are localized in membranes of the endoplasmic reticulum. Phenobarbital, which exacerbates acute intermittent porphyria in man, induces drug-oxidizing enzymes in liver. Additionally, patients in whome the primary gene defect (uroporphyrinogen-I-synthetase deficiency) of acute intermittent porphyria has become clinically expressed have low levels of hepatic steroid delta4-5alpha-reductase activity. This 5alpha-reductase deficiency in acute intermittent porphyria leads to the disproportionate generation of 5beta-steroid metabolites from precursor hormones; such steroid metabolites have significant porphyria-inducing action experimentally. In this study the effects of phenobarbital on drug oxidation and steroid 5alpha-reduction in man were examined to determine if this drug could produce changes in steroid 5alpha-reductase activity which mimicked those seen in patients with acute intermittent porphyria. Metabolic studies with [14C]-testosterone and 11beta-[3H]hydroxyandrostenedione were carried out in five normal volunteers. In all five subjects phenobarbital administration (2 mg/kg/per day for 21 days) enhanced plasma removal of the test drugs antipyrine and phenylbutazone as expected; but in four subjects phenobarbital also substantially depressed 5alpha-metabolite formation from [14C]testosterone and resulted in a pattern of hormone biotransformation characterized by a high ratio of 5beta/5alpha-metabolite formation. Studies with 11beta-[3H]hydroxy-androstenedione in three subjects confirmed that phenobarbital produced this high 5beta/5alpha ratio of steroid metabolism by depressing 5alpha-reductase activity for steroid hormones in liver. The high ratio of 5beta/5alpha-metabolites formed in normals after drug treatment mimicks the high 5beta/5alpha-steroid metabolite ratio formed from endogenous hormones in acute intermittent porphyria. The

  11. 5 alpha-reductase deficiency without hypospadias.

    PubMed Central

    Ng, W K; Taylor, N F; Hughes, I A; Taylor, J; Ransley, P G; Grant, D B

    1990-01-01

    A boy aged 4 with penoscrotal hypospadias and his brother aged 12 with micropenis had typical changes of homozygous 5 alpha-reductase deficiency. After three injections of chorionic gonadotrophin there was a trivial rise in plasma dihydrotestosterone with a normal increase in plasma testosterone. Urine steroid chromatography showed abnormally high 5 beta: 5 alpha ratios and 5 alpha-reductase activity was appreciably reduced in genital skin fibroblasts. The results indicate that 5 alpha-reductase deficiency is not invariably associated with genital ambiguity. PMID:2248513

  12. Relationship of changing delta 4-steroid 5 alpha-reductase activity to (125I)iododeoxyuridine uptake during regeneration of involuted rat prostates

    SciTech Connect

    Kitahara, S.; Higashi, Y.; Takeuchi, S.; Oshima, H. )

    1989-04-01

    To elucidate the phenotypic expression of proliferating prostatic cells, rats were castrated, and the regenerating process of involuted ventral prostates during testosterone propionate (TP) administration was investigated by examining morphology, (5-{sup 125}I)iododeoxyuridine ({sup 125}I-UdR) uptake, DNA content, weight, acid phosphatase, and delta 4-steroid 5 alpha-reductase (5 alpha-reductase) activities. Morphologically, TP treatment initially increased the number of epithelial cells lining glandular lobules and subsequently restored the shape of epithelial cells. {sup 125}I-UdR uptake peaked on Day 3 of TP treatment and stayed at higher levels than for uncastrated controls until Day 14 of treatment. Prostatic weight, protein content, acid phosphatase, and DNA content returned to uncastrated control levels by Day 14 of TP treatment. TP administration markedly stimulated prostatic 5 alpha-reductase activity, which peaked on the Day 5 of treatment and decreased to uncastrated control levels by Day 14 of treatment. It is concluded that TP administration to castrated rats initially induced active mitotic division of the remaining stem cells, followed by formation of differentiated functional epithelial cells. Prostatic 5 alpha-reductase was highly active at the initial phase of active mitotic cell division. The major portion of the increased enzyme activity can be regarded as a phenotypic expression of stem or transient cells of prostatic epithelium.

  13. Genetics Home Reference: 5-alpha reductase deficiency

    MedlinePlus

    ... gene provides instructions for making an enzyme called steroid 5-alpha reductase 2. This enzyme is involved ... external genitalia. Mutations in the SRD5A2 gene prevent steroid 5-alpha reductase 2 from effectively converting testosterone ...

  14. Theaflavin-3,3'-digallate and penta-O-galloyl-beta-D-glucose inhibit rat liver microsomal 5alpha-reductase activity and the expression of androgen receptor in LNCaP prostate cancer cells.

    PubMed

    Lee, Hung-Hsiao; Ho, Chi-Tang; Lin, Jen-Kun

    2004-07-01

    Androgens play a critical role in regulating the growth, differentiation and survival of epithelial cells in many androgen-responsive organs, such as prostate and skin. The enzyme steroid 5alpha-reductase (EC 1.3.99.5) catalyzes the conversion of testosterone (T) to a more active androgen, dihydrotestosterone (DHT). DHT then binds to androgen receptors (AR) and functions in the nucleus to regulate specific gene expression. Androgens via their cognate receptor may be involved in the development and progression of benign prostate hyperplasia, prostate cancer, hirsutism, male pattern alopecia and acne. The aim of this study was to determine whether theaflavin-3,3'-digallate (TF3) and penta-O-galloyl-beta-D-glucose (5GG) have inhibitory effects on androgen production and action. We found that TF3 and 5GG inhibit rat liver microsomal 5alpha-reductase activity. Furthermore, TF3 and 5GG significantly reduced androgen-responsive LNCaP prostate cancer cell growth, suppressed expression of the AR and lowered androgen-induced prostate-specific antigen secretion and fatty acid synthase protein level. In conclusion, our result suggests that TF3 and 5GG might be useful chemoprevention agents for prostate cancer through suppressing the function of androgen and its receptor. PMID:14963012

  15. An overview on 5alpha-reductase inhibitors.

    PubMed

    Aggarwal, Saurabh; Thareja, Suresh; Verma, Abhilasha; Bhardwaj, Tilak Raj; Kumar, Manoj

    2010-02-01

    Benign prostatic hyperplasia (BPH) is the noncancerous proliferation of the prostate gland associated with benign prostatic obstruction and lower urinary tract symptoms (LUTS) such as frequency, hesitancy, urgency, etc. Its prevalence increases with age affecting around 70% by the age of 70 years. High activity of 5alpha-reductase enzyme in humans results in excessive dihydrotestosterone levels in peripheral tissues and hence suppression of androgen action by 5alpha-reductase inhibitors is a logical treatment for BPH as they inhibit the conversion of testosterone to dihydrotestosterone. Finasteride (13) was the first steroidal 5alpha-reductase inhibitor approved by U.S. Food and Drug Administration (USFDA). In human it decreases the prostatic DHT level by 70-90% and reduces the prostatic size. Dutasteride (27) another related analogue has been approved in 2002. Unlike Finasteride, Dutasteride is a competitive inhibitor of both 5alpha-reductase type I and type II isozymes, reduced DHT levels >90% following 1 year of oral administration. A number of classes of non-steroidal inhibitors of 5alpha-reductase have also been synthesized generally by removing one or more rings from the azasteroidal structure or by an early non-steroidal lead (ONO-3805) (261). In this review all categories of inhibitors of 5alpha-reductase have been covered. PMID:19879888

  16. Role of 5 alpha-reductase in health and disease.

    PubMed

    Randall, V A

    1994-04-01

    The mechanism of androgen action varies in different tissues, but in the majority of androgen target tissues either testosterone or 5 alpha-dihydrotestosterone (DHT) binds to a specific androgen receptor to form a complex that can regulate gene expression. Testosterone is metabolized to DHT by the enzyme 5 alpha-reductase. The autosomal recessive genetic disorder of 5 alpha-reductase deficiency has clearly shown that the requirement for DHT formation varies with different tissues. In this syndrome genetic males contain normal male internal structures including testes, but exhibit ambiguous or female external genitalia at birth; at puberty they undergo partial virilization which includes development of a male gender identity even if brought up as females. Their development suggests that testosterone itself is able to stimulate psychosexual behaviour, development of the embryonic wolffian duct, muscle development, voice deepening, spermatogenesis, and axillary and pubic hair growth; DHT seems to be essential for prostate development and growth, the development of the external genitalia and male patterns of facial and body hair growth or male-pattern baldness. How different hormones operate to regulate genes via the same receptor is currently unknown, but appears to involve cell-specific factors. The 5-alpha-reductase enzyme has proved difficult to isolate biochemically, but recently at least two human isoenzymes have been identified using molecular biological methods. All the various 5 alpha-reductase-deficient kindreds have been shown to have mutations in 5 alpha-reductase 2, the predominant form in the prostate. The biological role of 5 alpha-reductase 1 has not yet been ascertained, but at present it cannot be ruled out that some of the actions ascribed to testosterone are indeed in cells producing DHT via this enzyme. The activity of 5 alpha-reductase is also implicated in benign prostatic hypertrophy, hirsutism and possibly male-pattern baldness; recent evidence

  17. New 5alpha-reductase inhibitors: in vitro and in vivo effects.

    PubMed

    Pérez-Ornelas, Víctor; Cabeza, Marisa; Bratoeff, Eugene; Heuze, Ivonne; Sánchez, Mauricio; Ramírez, Elena; Naranjo-Rodríguez, Elia

    2005-03-01

    The enzyme 5alpha-reductase is responsible for the conversion of testosterone (T) to its more potent androgen dihydrotestosterone (DHT). This steroid had been implicated in androgen-dependent diseases such as: benign prostatic hyperplasia, prostate cancer, acne and androgenic alopecia. The inhibition of 5alpha-reductase enzyme offers a potentially useful treatment for these diseases. In this study, we report the synthesis and pharmacological evaluation of several new 3-substituted pregna-4, 16-diene-6, 20-dione derivatives. These compounds were prepared from the commercially available 16-dehydropregnenolone acetate. The biological activity of the new steroidal derivatives was determined in vivo as well as in vitro experiments. In vivo experiments, the anti-androgenic effect of the steroids was demonstrated by the decrease of the weight of the prostate gland of gonadectomized hamster treated with T plus finasteride or the new steroids. The IC50 value of these steroids was determined by measuring the conversion of radio labeled T to DHT. The results of this study carried out with 5alpha-reductase enzyme from hamster and human prostate showed that four of the six steroidal derivatives (5, 7, 9, 10) exhibited much higher 5alpha-reductase inhibitory activity, as indicated by the IC50 values than the presently used Proscar 3 (finasteride). The comparison of the weight of the hamster's prostate gland indicated that compound 5 had a comparable weight decrease as finasteride. The overall data of this study showed very clearly those compounds 5, 7, 9, 10 are good inhibitors for the 5alpha-reductase enzyme. PMID:15763601

  18. Selective non-steroidal inhibitors of 5 alpha-reductase type 1.

    PubMed

    Occhiato, Ernesto G; Guarna, Antonio; Danza, Giovanna; Serio, Mario

    2004-01-01

    The enzyme 5 alpha-reductase (5 alpha R) catalyses the reduction of testosterone (T) into the more potent androgen dihydrotestosterone (DHT). The abnormal production of DHT is associated to pathologies of the main target organs of this hormone: the prostate and the skin. Benign prostatic hyperplasia (BPH), prostate cancer, acne, androgenetic alopecia in men, and hirsutism in women appear related to the DHT production. Two isozymes of 5 alpha-reductase have been cloned, expressed and characterized (5 alpha R-1 and 5 alpha R-2). They share a poor homology, have different chromosomal localization, enzyme kinetic parameters, and tissue expression patterns. Since 5 alpha R-1 and 5 alpha R-2 are differently distributed in the androgen target organs, a different involvement of the two isozymes in the pathogenesis of prostate and skin disorders can be hypothesized. High interest has been paid to the synthesis of inhibitors of 5 alpha-reductase for the treatment of DHT related pathologies, and the selective inhibition of any single isozyme represents a great challenge for medical and pharmaceutical research in order to have more specific drugs. At present, no 5 alpha R-1 inhibitor is marketed for the treatment of 5 alpha R-1 related pathologies but pharmaceutical research is very active in this field. This paper will review the major classes of 5 alpha R inhibitors focusing in particular on non-steroidal inhibitors and on structural features that enhance the selectivity versus the type 1 isozyme. Biological tests to assess the inhibitory activity towards the two 5 alpha R isozymes will be also discussed. PMID:15026079

  19. Regulation of 5alpha-reductase isoforms by oxytocin in the rat ventral prostate.

    PubMed

    Assinder, S J; Johnson, C; King, K; Nicholson, H D

    2004-12-01

    Oxytocin (OT) is present in the male reproductive tract, where it is known to modulate contractility, cell growth, and steroidogenesis. Little is known about how OT regulates these processes. This study describes the localization of OT receptor in the rat ventral prostate and investigates if OT regulates gene expression and/or activity of 5alpha-reductase isoforms I and II. The ventral prostates of adult male Wistar rats were collected following daily sc administration of saline (control), OT, a specific OT antagonist or both OT plus antagonist for 3 d. Expression of the OT receptor was identified in the ventral prostate by RT-PCR and Western blot, and confirmed to be a single active binding site by radioreceptor assay. Immunohistochemistry localized the receptor to the epithelium of prostatic acini and to the stromal tissue. Real-time RT-PCR determined that OT treatment significantly reduced expression of 5alpha-reductase I but significantly increased 5alpha-reductase II expression in the ventral prostate. Activity of both isoforms of 5alpha-reductase was significantly increased by OT, resulting in increased concentration of prostatic dihydrotestosterone. In conclusion, OT is involved in regulating conversion of testosterone to the biologically active dihydrotestosterone in the rat ventral prostate. It does so by differential regulation of 5alpha-reductase isoforms I and II.

  20. Finasteride: the first 5 alpha-reductase inhibitor.

    PubMed

    Sudduth, S L; Koronkowski, M J

    1993-01-01

    Finasteride is a synthetic 4-azasteroid that is a specific competitive inhibitor of 5 alpha-reductase, an intracellular enzyme that converts testosterone to dihydrotestosterone (DHT). It has no binding affinity for androgen receptor sites and itself possesses no androgenic, antiandrogenic, or other steroid hormone-related properties. It is well absorbed after oral administration, with absolute bioavailability in humans of 63% (range 34-108%). The mean time to maximum concentration is 1-2 hours, and it is approximately 90% plasma protein bound. The elimination half-life averages 6-8 hours. The agent is metabolized to a series of five metabolites, of which two are active and possess less than 20% of the 5 alpha-reductase activity of finasteride. Little is known about potential drug interactions, although they appear to be minimal and not clinically relevant. The drug is indicated for the treatment of symptomatic benign prostatic hyperplasia. Its efficacy in regression of prostate gland enlargement is rapid and predictable, although correlation with subsequent improvement in urinary flow and symptoms is highly variable. Dosages of 0.5-100 mg/day regress prostate enlargement; the recommended dosage is 5 mg once/day. Finasteride may hold promise for other DHT-mediated disorders such as acne, facial hirsutism, frontal lobe alopecia, and prostate cancer, but its use in these conditions remains investigational. The frequency of adverse drug events is low, with the most common side effects being impotence, decreased libido, and decreased volume of ejaculate. No reports of intentional overdose have been reported, and dosages of up to 80 mg/day for 3 months have been taken without adverse effect. PMID:7689728

  1. Molecular genetics of steroid 5 alpha-reductase 2 deficiency.

    PubMed Central

    Thigpen, A E; Davis, D L; Milatovich, A; Mendonca, B B; Imperato-McGinley, J; Griffin, J E; Francke, U; Wilson, J D; Russell, D W

    1992-01-01

    Two isozymes of steroid 5 alpha-reductase encoded by separate loci catalyze the conversion of testosterone to dihydrotestosterone. Inherited defects in the type 2 isozyme lead to male pseudohermaphroditism in which affected males have a normal internal urogenital tract but external genitalia resembling those of a female. The 5 alpha-reductase type 2 gene (gene symbol SRD5A2) was cloned and shown to contain five exons and four introns. The gene was localized to chromosome 2 band p23 by somatic cell hybrid mapping and chromosomal in situ hybridization. Molecular analysis of the SRD5A2 gene resulted in the identification of 18 mutations in 11 homozygotes, 6 compound heterozygotes, and 4 inferred compound heterozygotes from 23 families with 5 alpha-reductase deficiency. 6 apparent recurrent mutations were detected in 19 different ethnic backgrounds. In two patients, the catalytic efficiency of the mutant enzymes correlated with the severity of the disease. The high proportion of compound heterozygotes suggests that the carrier frequency of mutations in the 5 alpha-reductase type 2 gene may be higher than previously thought. Images PMID:1522235

  2. Regulation of androgen receptor and 5 alpha-reductase in the skin of normal and hirsute women.

    PubMed

    Mauvais-Jarvis, P

    1986-05-01

    The hormonal activity of androgens is mediated in target cells, particularly in human skin, by two kinds of proteins: the androgen receptor and the enzyme 5 alpha-reductase. In well differentiated androgen target cells, 5 alpha-reductase achieves the transformation of testosterone (T) into dihydrotestosterone (DHT), a more active androgen than T, because of its higher affinity for the receptor. In other words, 5 alpha-reductase acts as an amplifier of the androgen signal but is not absolutely required for androgen action. Regarding the regulation of the androgen receptor, minimal information is available. However, in genital skin, the receptor seems to be predominantly localized in the cytosolic compartment before puberty in males and in the nuclear compartment after puberty. In hirsute patients, recent data on genital skin fibroblasts do not show significant differences between the binding capacity of fibroblasts from normal and hirsute women whereas there is no difference between normal men and women. 5 alpha-Reductase activity seems to be a very important step in the processes involved in androgen action. While 5 alpha-reductase activity present in the skin of external genitalia does not seem to be androgen dependent, this is not the case for the enzyme located in pubic skin. In this area, a sex difference between males and females may be observed both in skin homogenates and in cultured fibroblasts. In addition DHT added to a medium of pubic skin fibroblasts is capable of increasing 5 alpha-reductase activity. This increase is not observed when cyproterone acetate is added to the medium and in patients with testicular feminization syndrome without receptors. Pubic 5 alpha-reductase activity is an androgen receptor mediated phenomenon. In patients with hirsutism, and particularly idiopathic hirsutism, 5 alpha-reductase activity is high without an increase in circulating androgens. This may be observed both in pubic skin homogenates and in cultured fibroblasts

  3. 5 alpha-reductase deficiency in patients with micropenis.

    PubMed

    Gad, Y Z; Nasr, H; Mazen, I; Salah, N; el-Ridi, R

    1997-03-01

    The enzyme 5 alpha-reductase (5 alpha R), by virtue of its peripheral 5 alpha-reduction of testosterone (T) to dihydrotestosterone (DHT), is believed to play a major role in the differentiation and the subsequent growth of the penis. However, recent studies have reported 5 alpha R deficiency (5 alpha RD) in patients with isolated micropenis and hypothesized that 5 alpha RD is not invariably associated with genital ambiguity. In Egypt, 5 alpha RD has been reported frequently among intersex patients. The aim of this study was to assess the role of 5 alpha RD in the development of micropenis among Egyptian patients with abnormal sexual development. The study included 29 patients who were categorized into three groups (isolated micropenis, 9 patients; microphallus with genital ambiguity, 11 patients; genital ambiguity with normal-sized phallus, 9 patients). Activity of 5 alpha R was assessed by estimating T/DHT ratios in the basal state in pubertal subjects and following human chorionic gonadotropin (HCG) stimulation test in prepubertals. The results showed that the incidence of 5 alpha RD was much higher in cases of ambiguous genitalia with micropenis (5 families out of 10, 50%) than in those with isolated microphallus (1/9, 11.1%) or those with ambiguous genitalia and normal-sized phallus (1/8, 12.5%). In conclusion, the study showed that isolated micropenis is a heterogeneous disorder and that 5 alpha RD, despite its relative prevalence in Egypt, has a minimal role in the aetiology. On the other hand, 5 alpha RD seems to correlate with penile length in intersex cases.

  4. Phenotypic classification of male pseudohermaphroditism due to steroid 5{alpha}-reductase 2 deficiency

    SciTech Connect

    Sinnecker, G.H.G; Hiort, O.; Kruse, K.; Dibbelt, L.

    1996-05-03

    Conversion of testosterone (T) to dihydrotestosterone (DHT) in genital tissue is catalysed by the enzyme 5{alpha}-reductase 2, which is encoded by the SRD5A2 gene. The potent androgen DHT is required for full masculinization of the external genitalia. Mutations of the SRD5A2 gene inhibit enzyme activity, diminish DHT formation, and hence cause masculinization defects of varying degree. The classical syndrome, formerly described as pseudovaginal perineoscrotal hypospadias, is characterized by a predominantly female phenotype at birth and significant virilization without gynecomastia at puberty. We investigated nine patients with steroid 5{alpha}-reductase 2 deficiency (SRD). T/DHT-ratios were highly increased in the classical syndrome, but variable in the less severe affected patients. Mutations in the SRD5A2 gene had been characterized using PCR-SSCP analysis and direct DNA sequencing. A small deletion was encountered in two patients, while all other patients had single base mutations which result in amino acid substitutions. We conclude that phenotypes may vary widely in patients with SRD5A2 gene mutations spanning the whole range from completely female to normal male without distinctive clinical signs of the disease. Hence, steroid 5{alpha}-reductase deficiency should be considered not only in sex reversed patients with female or ambiguous phenotypes, but also in those with mild symptoms of undermasculinization as encountered in patients with hypospadias and/or micropenis. A classification based on the severity of the masculinization defect may be used for correlation of phenotypes with enzyme activities and genotypes, and for comparisons of phenotypes between different patients as the basis for clinical decisions to be made in patients with pseudohermaphroditism due to steroid 5{alpha}-reductase 2 deficiency. 22 refs., 2 figs., 2 tabs.

  5. 5-Alpha-Reductase Inhibitors and Combination Therapy.

    PubMed

    Füllhase, Claudius; Schneider, Marc P

    2016-08-01

    By inhibiting the conversion from testosterone to dihydrotestosterone 5-Alpha reductase inhibitors (5ARIs) are able to hinder prostatic growth, shrink prostate volumes, and improve BPH-related LUTS. 5ARIs are particularly beneficial for patients with larger prostates (>30-40ml). Generally the side effects of 5ARI treatment are mild, and according to the FORTA classification 5ARIs are suitable for frail elderly. 5ARI / alpha-blocker (AB) combination therapy showed the best symptomatic outcome and risk reduction for clinical progression. Combining Phosphodieseterase type 5 inhbibitors (PDE5Is) with 5ARIs counteracts the negative androgenic sexual side effects of 5ARIs, and simultaneously combines their synergistic effects on LUTS. PMID:27476125

  6. 5alpha-reductase: history and clinical importance.

    PubMed

    Marks, Leonard S

    2004-01-01

    The treatment of men with symptomatic benign prostatic hyperplasia (BPH) has shifted dramatically from surgery to drug therapy over the past decade. The revolution in BPH treatment began with the discovery of congenital 5alpha-reductase (5AR) deficiency, leading to the appreciation of 2 different androgenic hormones: testosterone, which mediates overt masculinization in the adult male, and dihydrotestosterone (DHT), which mediates prostatic growth, acne, facial beard, and male pattern baldness. Inhibition of DHT in adults results in prostatic shrinkage and symptomatic relief in many men, without the side effects seen with conventional androgen-deprivation therapy. The 5AR inhibitor drugs (finasteride and the dual inhibitor, dutasteride) are able to ablate the accumulation of intraprostatic DHT, the mechanism most responsible for prostate growth and maintenance. Not only may these drugs relieve symptoms, but they may also alter the natural history of the BPH process. Future indications for the 5ARI drugs could include chemoprevention of prostate cancer, prophylaxis of BPH-related complications, and treatment of BPH-associated hematuria. PMID:16985920

  7. Prostates, pates, and pimples. The potential medical uses of steroid 5 alpha-reductase inhibitors.

    PubMed

    Tenover, J S

    1991-12-01

    The steroid 5 alpha-reductase enzyme is responsible for the formation of DHT from testosterone. DHT has been the major androgen implicated in the pathogenesis of benign prostatic hyperplasia, male pattern baldness, acne, and idiopathic female hirsutism. Although specific inhibitors of 5 alpha-reductase are not yet generally available for human use, it is expected that they will become available within the next several years. Based on biochemical, histologic, and anatomic information from animals given 5 alpha-reductase inhibitors, preliminary data on their use in humans, and knowledge gained from men with the inherited 5 alpha-reductase deficiency, it is expected that these 5 alpha-reductase inhibitors may have a major role in the medical management of benign prostatic hyperplasia. In addition, it is possible that these compounds will hold promise for the prevention of male pattern baldness and for the treatment of resistant acne and idiopathic hirsutism. PMID:1723383

  8. 5 alpha-reductase inhibitors and prostatic disease.

    PubMed

    Schröder, F H

    1994-08-01

    5 alpha-Reductase inhibitors are a new class of substances with very specific effects on type I and type II 5 alpha R which may be of use in the treatment of skin disease, such as male pattern baldness, male acne and hirsutism, as well as prostatic hyperplasia and prostate cancer. At least two types of 5 alpha R inhibitors with a different pH optimum have been described. cDNA encoding for both the type I and the type II enzyme has been cloned. Most of the orally effective 5 alpha R inhibitors belong to the class of 4-azasteroids. The radical substituted in the 17 position of the steroid ring seems to be related to species specific variations and to the types of 5 alpha R enzymes in different species and organ systems. 5 alpha R inhibitors lead to a decrease of plasma DHT by about 65% while there is a slight rise in plasma testosterone. The decrease of tissue DHT in the ventral prostate of the intact rat, the dog and in humans is more pronounced and amounts to about 85%. There is a reciprocal rise of tissue T in these systems. The application of an inhibitor of 5 alpha R type II leads to a shrinkage of BPH in men by about 30%. In the rat a similar shrinkage accompanied by a significant decrease of total organ DNA occurs. This decrease, however, is not as pronounced as can be achieved with castration.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7522999

  9. In vivo and in vitro effect of novel 4,16-pregnadiene-6,20-dione derivatives, as 5alpha-reductase inhibitors.

    PubMed

    Bratoeff, Eugene; Cabeza, Marisa; Pérez-Ornelas, Victor; Recillas, Sergio; Heuze, Ivonne

    2008-09-01

    In this study, we report the synthesis and biological evaluation of several new 3-substituted pregna-4,16-diene-6,20-dione derivatives (11a-11d). These compounds were prepared from the commercially available 16-dehydropregnenolone acetate. The biological effect of these steroids was demonstrated in in vivo and in vitro experiments. In the in vivo experiments, we measured the activity of the 11a-11d on the weight of the prostate gland of gonadectomized hamsters treated with testosterone plus finasteride or with the new steroids. For the studies in vitro, we determined the IC50 values by measuring the steroid concentration that inhibits 50% of the activity of 5alpha-reductase present in human prostate. In order to study the mechanism of action of 11a-11d, we also determined the capacity of these steroids to bind to the androgen receptor (AR) present in the rat prostate cytosol using labeled mibolerone as a tracer. The results from this work indicated that compounds 11a-11d significantly decreased the weight of the prostate as compared to testosterone treated animals and this reduction of the weight of the prostate was comparable to that produced by the finasteride. On the other hand 11a-11d exhibited a high inhibitory activity for the human 5alpha-reductase enzyme with IC50 values of 1.4 x 10(-8), 1.8 x 10(-9), 1.0 x 10(-8) and 4 x 10(-5) respectively. However the IC50 value of 11a (1.8 x 10(-9)) was the only one lower than that of finasteride (8.5 x 10(-9)). Nevertheless this compound did not show a higher potency in vivo as compared to that of compounds 11b-11d. The competition analysis for the androgen receptor indicated that the IC50 value of non-labeled mibolerone used in this experiment was 1nM, whereas steroids 10, 11a-11d did not inhibit the labeled mibolerone binding to the androgen receptor. On the other hand, steroid 10 did not show any activities in vitro or in vivo, and for this reason these steroidal derivatives (11a-11d) cannot be considered as

  10. Different patterns of 5{alpha}-reductase expression, cellular distribution, and testosterone metabolism in human follicular dermal papilla cells

    SciTech Connect

    Liu, Shicheng Yamauchi, Hitoshi

    2008-04-18

    Androgens regulate hair growth, and 5{alpha}-reductase (5{alpha}R) plays a pivotal role in the action of androgens on target organs. To clarify the molecular mechanisms responsible for controlling hair growth, the present study presents evidence that the human follicular dermal papilla cells (DPCs) from either beard (bDPCs) or scalp hair (sDPCs) possess endogenous 5{alpha}R activity. Real-time RT-PCR revealed that the highest level of 5{alpha}R1 mRNA was found in bDPCs, followed by sDPCs, and a low but detectable level of 5{alpha}R1 mRNA was observed in fibroblasts. Minimally detectable levels of 5{alpha}R2 mRNA were found in all three cell types. A weak band at 26 kDa corresponding to the human 5{alpha}R1 protein was detected by Western blot in both DPCs, but not in fibroblasts. Immuonofluorescence analysis confirmed that 5{alpha}R1 was localized to the cytoplasm rather than in the nuclei in both DPCs Furthermore, a 5{alpha}R assay using [{sup 14}C]testosterone labeling in intact cells revealed that testosterone was transformed primarily into androstenedione, and in small amounts, into DHT. Our results demonstrate that the 5{alpha}R activities of either bDPCs or sDPCs are stronger than that of dermal fibroblasts, despite the fact that the major steroidogenic activity is attributed to 17{beta}-HSD rather than 5{alpha}R among the three cell types. The 5{alpha}R1 inhibitor MK386 exhibited a more potent inhibitory effect on 5{alpha}R activity than finasteride (5{alpha}R2 inhibitor) in bDPCs.

  11. Chronic ethanol ingestion during puberty alters the transient increase in testicular 5 alpha-reductase in the Swiss-Webster mouse.

    PubMed

    Anderson, R A; Phillips, J F; Zaneveld, L J

    1989-01-01

    Previous experiments with inbred mice showed that chronic ethanol treatment delays male pubertal development. An initial event in sexual maturation in the rat is a transient increase in 5 alpha-reductase. The present study was conducted to determine whether similar ethanol effects occur in outbred mice (Swiss-Webster), to determine the ontological profile of testicular 5 alpha-reductase in the mouse, and to evaluate the effect of ethanol treatment on this enzyme. After 29 days of treatment with a liquid diet (beginning at age 20 days), reductions in the ethanol-treated mice as compared with the controls were noted in testicular weight (55.0 +/- 2.0 vs. 63.0 +/- 2.4 mg; P less than 0.01), epididymal sperm content (6.8 X 10(5) vs. 14.4 X 10(5); P less than 0.05), and sperm motility (45% vs. 57%; P less than 0.05). After 43 days, differences no longer existed. In chow-fed mice, a substantial rise in 5 alpha-reductase (1 unit = 1 pmole DHT formed/45 min/mg testis) began at age 24 days. Activity peaked at approximately 65 units at 25 to 30 days and gradually declined to 6.4 +/- 0.8 units at 63 days. After 29 days treatment, 5 alpha-reductase of the pair-fed control group was 26.8 +/- 4.9 units, which decreased to a baseline value of 7.0 +/- 2.1 units after 43 days treatment. In contrast, 5 alpha-reductase of the ethanol-treated group remained at baseline levels after 29 days (7.7 +/- 2.3 units) and 43 days of treatment (7.6 +/- 2.3 units).(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Adverse Effects and Safety of 5-alpha Reductase Inhibitors (Finasteride, Dutasteride): A Systematic Review

    PubMed Central

    Hirshburg, Jason M.; Kelsey, Petra A.; Therrien, Chelsea A.; Gavino, A. Carlo; Reichenberg, Jason S.

    2016-01-01

    Finasteride and dutasteride, both 5-alpha reductase inhibitors, are considered first-line treatment for androgenetic hair loss in men and used increasingly in women. In each case, patients are expected to take the medications indefinitely despite the lack of research regarding long-term adverse effects. Concerns regarding the adverse effects of these medications has led the United States National Institutes of Health to add a link for post-finasteride syndrome to its Genetic and Rare Disease Information Center. Herein, the authors report the results of a literature search reviewing adverse events of 5-alpha reductase inhibitors as they relate to prostate cancer, psychological effects, sexual health, and use in women. Several large studies found no increase in incidence of prostate cancer, a possible increase of high-grade cancer when detected, and no change in survival rate with 5-alpha reductase inhibitor use. Currently, there is no direct link between 5-alpha reductase inhibitor use and depression; however, several small studies have led to depression being listed as a side effect on the medication packaging. Sexual effects including erectile dysfunction and decreased libido and ejaculate were reported in as many as 3.4 to 15.8 percent of men. To date, there are very few studies evaluating 5-alpha reductase inhibitor use in women. Risks include birth defects in male fetuses if used in pregnancy, decreased libido, headache, gastrointestinal discomfort, and isolated reports of changes in menstruation, acne, and dizziness. Overall, 5-alpha reductase inhibitors were well-tolerated in both men and women, but not without risk, highlighting the importance of patient education prior to treatment. PMID:27672412

  13. The biochemical and phenotypic characterization of females homozygous for 5 alpha-reductase-2 deficiency.

    PubMed

    Katz, M D; Cai, L Q; Zhu, Y S; Herrera, C; DeFillo-Ricart, M; Shackleton, C H; Imperato-McGinley, J

    1995-11-01

    The biochemical and physiologic manifestations of decreased 5 alpha-dihydrotestosterone (DHT) in females are characterized. Three females from the large Dominican kindred with 5 alpha-reductase-2 deficiency were identified as homozygous for a point mutation (R246W, C-->T) on exon 5 of the 5 alpha-reductase-2 gene by single strand DNA conformational polymorphism analysis and DNA sequence analysis. Body hair was decreased; there was no history of acne. Despite delayed menarche, all were fertile, and two had twins. Urinary 5 beta/5 alpha C19 and C21 steroid metabolite ratios were elevated. Plasma testosterone was normal to elevated, with low DHT, resulting in an increased testosterone/DHT ratio. 3 alpha,5 alpha-Androstanediol glucuronide was low. Menstrual cycle profiling performed in two subjects showed ovulatory gonadotropin peaks. Sebum production was normal. 5 alpha-Reductase-2-deficient homozygotic females demonstrate the importance of DHT in the physiology and pathophysiology of body hair growth. Normal sebum implies regulation by the 5 alpha-reductase-1 isoenzyme. Delayed puberty suggests involvement of 5 alpha-reductase-2 in menarche at the hypothalamic/pituitary and/or ovarian level. As two had nonidentical twins, DHT and/or the DHT/estradiol ratio may regulate follicular development, with lower levels permitting more than one dominant follicle per cycle and higher levels impairing follicular development and ovulation. Thus, females with 5 alpha-reductase-2 deficiency highlight a role for DHT in hirsutism and/or menstrual disorders. PMID:7593420

  14. Adverse Effects and Safety of 5-alpha Reductase Inhibitors (Finasteride, Dutasteride): A Systematic Review

    PubMed Central

    Hirshburg, Jason M.; Kelsey, Petra A.; Therrien, Chelsea A.; Gavino, A. Carlo; Reichenberg, Jason S.

    2016-01-01

    Finasteride and dutasteride, both 5-alpha reductase inhibitors, are considered first-line treatment for androgenetic hair loss in men and used increasingly in women. In each case, patients are expected to take the medications indefinitely despite the lack of research regarding long-term adverse effects. Concerns regarding the adverse effects of these medications has led the United States National Institutes of Health to add a link for post-finasteride syndrome to its Genetic and Rare Disease Information Center. Herein, the authors report the results of a literature search reviewing adverse events of 5-alpha reductase inhibitors as they relate to prostate cancer, psychological effects, sexual health, and use in women. Several large studies found no increase in incidence of prostate cancer, a possible increase of high-grade cancer when detected, and no change in survival rate with 5-alpha reductase inhibitor use. Currently, there is no direct link between 5-alpha reductase inhibitor use and depression; however, several small studies have led to depression being listed as a side effect on the medication packaging. Sexual effects including erectile dysfunction and decreased libido and ejaculate were reported in as many as 3.4 to 15.8 percent of men. To date, there are very few studies evaluating 5-alpha reductase inhibitor use in women. Risks include birth defects in male fetuses if used in pregnancy, decreased libido, headache, gastrointestinal discomfort, and isolated reports of changes in menstruation, acne, and dizziness. Overall, 5-alpha reductase inhibitors were well-tolerated in both men and women, but not without risk, highlighting the importance of patient education prior to treatment.

  15. Adverse Effects and Safety of 5-alpha Reductase Inhibitors (Finasteride, Dutasteride): A Systematic Review.

    PubMed

    Hirshburg, Jason M; Kelsey, Petra A; Therrien, Chelsea A; Gavino, A Carlo; Reichenberg, Jason S

    2016-07-01

    Finasteride and dutasteride, both 5-alpha reductase inhibitors, are considered first-line treatment for androgenetic hair loss in men and used increasingly in women. In each case, patients are expected to take the medications indefinitely despite the lack of research regarding long-term adverse effects. Concerns regarding the adverse effects of these medications has led the United States National Institutes of Health to add a link for post-finasteride syndrome to its Genetic and Rare Disease Information Center. Herein, the authors report the results of a literature search reviewing adverse events of 5-alpha reductase inhibitors as they relate to prostate cancer, psychological effects, sexual health, and use in women. Several large studies found no increase in incidence of prostate cancer, a possible increase of high-grade cancer when detected, and no change in survival rate with 5-alpha reductase inhibitor use. Currently, there is no direct link between 5-alpha reductase inhibitor use and depression; however, several small studies have led to depression being listed as a side effect on the medication packaging. Sexual effects including erectile dysfunction and decreased libido and ejaculate were reported in as many as 3.4 to 15.8 percent of men. To date, there are very few studies evaluating 5-alpha reductase inhibitor use in women. Risks include birth defects in male fetuses if used in pregnancy, decreased libido, headache, gastrointestinal discomfort, and isolated reports of changes in menstruation, acne, and dizziness. Overall, 5-alpha reductase inhibitors were well-tolerated in both men and women, but not without risk, highlighting the importance of patient education prior to treatment. PMID:27672412

  16. The use of 5-alpha reductase inhibitors for the prevention of prostate cancer.

    PubMed

    Yu, Eun-mi; El-Ayass, Walid; Aragon-Ching, Jeanny B

    2010-07-01

    The use of 5-alpha-reductase inhibitors has been studied not only in benign prostatic hyperplasia, but as a chemopreventive strategy in prostate cancer. Both finasteride and dutasteride, 5 alpha-reductase inhibitors (5ARI), have been shown to decrease the risk of prostate cancer. The results of the REDUCE trial using the dual alpha-reductase isoenzyme inhibitor dutasteride, has recently been published by Andriole et al. in the New England Journal of Medicine. Certain considerations regarding its use and applicability to men with high risk of developing prostate cancer are herein discussed. PMID:20574153

  17. Tissue distribution and ontogeny of steroid 5 alpha-reductase isozyme expression.

    PubMed Central

    Thigpen, A E; Silver, R I; Guileyardo, J M; Casey, M L; McConnell, J D; Russell, D W

    1993-01-01

    The synthesis of dihydrotestosterone is catalyzed by steroid 5 alpha-reductase isozymes, designated types 1 and 2. Mutation of type 2 results in male pseudohermaphroditism, in which the external genitalia are phenotypically female at birth. Two striking and unexplained features of this disorder are that external genitalia of affected males undergo virilization during puberty and that these individuals have less temporal hair regression. The tissue-specific and developmental expression patterns of the 5 alpha-reductase isozymes were investigated by immunoblotting. The type 1 isozyme is not detectable in the fetus, is transiently expressed in newborn skin and scalp, and permanently expressed in skin from the time of puberty. There was no qualitative difference in 5 alpha-reductase type 1 expression between adult balding vs. nonbalding scalp. The type 2 isozyme is transiently expressed in skin and scalp of newborns. Type 2 is the predominant isozyme detectable in fetal genital skin, male accessory sex glands, and in the prostate, including benign prostatic hyperplasia and prostate adenocarcinoma tissues. Both isozymes are expressed in the liver, but only after birth. These results are consistent with 5 alpha-reductase type 1 being responsible for virilization in type 2-deficient subjects during puberty, and suggest that the type 2 isozyme may be an initiating factor in development of male pattern baldness. Images PMID:7688765

  18. Male pseudohermaphroditism due to 5 alpha-reductase-2 deficiency in an Arab kindred.

    PubMed Central

    al-Attia, H. M.

    1997-01-01

    Six Arabs subjects (three postpubertal, two prepubertal and one pubertal) from three interrelated Omani families with male pseudohermaphroditism due to 5 alpha-reductase-2 deficiency were evaluated. These subjects had been raised as girls since birth as they were born with a clitoral-like phallus and ambiguous external genitalia of pseudovaginal perineoscrotal hypospadias with separate urethral and vaginal orifices. They underwent variable degrees of increased muscular habitus and phallic enlargement during puberty and beyond. Gynaecomastia was absent and the body and facial hair was insignificant. After diagnosis, a transition to male social sex occurred in two cases, one of which was interventional. Two retained the female social sex, one of which was also interventional, while the other two maintained an equivocal gender status. This report provides new data on the characterisation of 5 alpha-reductase-2 deficiency in various clusters. Images Figure 2 Figure 3 PMID:9497950

  19. 5alpha-Reductase inhibitor treatment of prostatic diseases: background and practical implications.

    PubMed

    Dörsam, J; Altwein, J

    2009-01-01

    This literature review discusses the theoretical background of 5alpha-reductase inhibitor (5ARI) treatment and the resulting clinical implications. A Medline-based search for peer-reviewed articles addressing 5ARIs, benign prostatic hyperplasia and prostate cancer was performed. The 5ARIs Finasteride and Dutasteride, which specifically inhibit the production of dihydrotestosterone by acting as competitive inhibitors of 5alpha-reductase, are clinically well tolerated and represent an effective treatment option for benign prostatic obstruction. Finasteride is the first compound which has a proven efficacy in chemoprevention of prostate cancer. The aim of this review was to elucidate, if there are sufficient data available to point out clinically relevant differences between the drugs. Both compounds achieve a significant reduction of prostate volume, an improvement of symptoms and a lower risk of acute urinary retention. Whether the different pharmacokinetic and pharmacodynamic properties of Finasteride and Dutasteride are of clinical importance cannot be judged at this time. PMID:19030020

  20. 5-Alpha-Reductase 2 Deficiency in a Woman with Primary Amenorrhea

    PubMed Central

    Kalantar Hormozi, Mohammadreza; Iranparvar Alamdari, Manouchehr; Tavosi, Zahra

    2013-01-01

    Steroid 5-alpha-reductase 2 deficiency is a rare disorder leading to male pseudohermaphroditism, a condition characterized by incomplete differentiation of male genitalia in 46,XY patients. Here, we report a case of a 21-year-old woman from Ardabil who presented with primary amenorrhea, ambiguous genitalia, and lack of breast development. All of the serum hormone profiles were normal except for raised serum total testosterone. Testosterone to DHT ratio (T/DHT) was elevated before (15.72) and further increased after hCG stimulation (32.46). A chromosomal study revealed a 46,XY karyotype. A bilateral gonadectomy, recessive cliteroplasty, urethroplasty, and vaginoplasty were performed and hormonal replacement therapy using estrogen was started. In conclusion, the diagnosis of 5-alpha-reductase 2 deficiency may be suspected in infants with ambiguous genitalia or in adolescents or young adults with the characteristic phenotype and serum hormone profiles. PMID:24383016

  1. Ockham's razor and selective androgen receptor modulators (SARMs): are we overlooking the role of 5alpha-reductase?

    PubMed

    Gao, Wenqing; Dalton, James T

    2007-02-01

    Selective Androgen Receptor Modulators (SARMs) are a novel class of AR ligands that possess tissue-selective pharmacological activities. SARMs of various chemical structures have been discovered and characterized, and lead compounds with much improved specificity for AR, in vivo pharmacokinetic profiles, and higher degree of tissue selectivity have entered clinical development, and are expected to dramatically expand the clinical applications of androgens. With the rapid progress in SARM discovery and increasing demand for mechanism-based drug design, more and more research efforts have been devoted to the mechanisms of action of the observed tissue selectivity of SARMs. There is increasing enthusiasm in adapting the molecular mechanisms of action from SERM research to the SARM field; however, is the SARM story really so complicated? The tissue-specific expression of 5alpha-reductase might provide a simple explanation for this puzzle.

  2. Differential expression of 5-alpha reductase isozymes in the prostate and its clinical implications

    PubMed Central

    Wang, Kai; Fan, Dong-Dong; Jin, Song; Xing, Nian-Zeng; Niu, Yi-Nong

    2014-01-01

    The development of human benign or malignant prostatic diseases is closely associated with androgens, primarily testosterone (T) and dihydrotestosterone (DHT). T is converted to DHT by 5-alpha reductase (5-AR) isozymes. Differential expression of 5-AR isozymes is observed in both human benign and malignant prostatic tissues. 5-AR inhibitors (5-ARI) are commonly used for the treatment of benign prostatic hyperplasia (BPH) and were once promoted as chemopreventive agents for prostate cancer (PCa). This review discusses the role of the differential expression of 5-AR in the normal development of the human prostate and in the pathogenesis and progression of BPH and PCa. PMID:24457841

  3. The REDUCE trial: chemoprevention in prostate cancer using a dual 5alpha-reductase inhibitor, dutasteride.

    PubMed

    Musquera, Mireia; Fleshner, Neil E; Finelli, Antonio; Zlotta, Alexandre R

    2008-07-01

    Dutasteride, a dual 5alpha-reductase inhibitor, is used in the treatment of benign prostatic hyperplasia (BPH). It reduces serum prostate-specific antigen levels by approximately 50% at 6 months and total prostate volume by 25% after 2 years. Randomized placebo-controlled trials in BPH patients have shown the efficacy of dutasteride in symptomatic relief, improvements in quality of life and peak urinary flow rate. Side effects occurring with dutasteride are decreased libido, erectile dysfunction, ejaculation disorders and gynecomastia. Preliminary data from placebo-controlled BPH trials have shown a decrease in the detection of prostate cancer in patients treated with dutasteride, although these studies were not designed to look at this issue. Dutasteride differs from finasteride in that it inhibits both isoenzymes of 5alpha-reductase, type I and type II. The landmark Prostate Cancer Prevention Trial at the end of the 7-year study demonstrated a 24.8% reduction in the incidence of prostate cancer in the finasteride group compared with placebo. However, a 25.5% increase in the prevalence of high-grade Gleason tumors has been observed, the clinical significance of which has been debated. Preliminary data suggest a decrease in prostate cancer incidence in dutasteride-treated patients and demonstrate type I alphareductase enzyme expression in prostate cancer. As a result, dutasteride is being investigated for prostate cancer prevention in the ongoing Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial, which is discussed here. PMID:18588452

  4. Molecular study of the 5 {alpha}-reductase type 2 gene in three European families with 5 {alpha}-reductase deficiency

    SciTech Connect

    Boudon, C.; Lumbroso, S.; Lobaccaro, J.M. ||

    1995-07-01

    The molecular basis of 5{alpha}-reductase (5{alpha}R) deficiency was investigated in four patients from three European families. In the French family, the first patient was raised as a female, and gonadectomy was performed before puberty. The second sibling, also raised as female, differed in that gonadal removal was performed after the onset of pubertal masculinization. The other two patients, both from Polish families, developed masculinization of external genitalia during puberty. All patients developed a female sexual identity. In all cases, no known consanguinity or family history of 5{alpha}R deficiency was reported. The genomic DNAs of the patients were sequenced after polymerase chain reaction amplification of the five exons of the 5{alpha}R type 2 gene. We found two homozygous mutations responsible for gutamine to arginine and histidine to arginine substitution in families 1 and 3, respectively. In family 2, we found a heterozygous mutation responsible for an asparagine to serine substitution at position 193. The glutamine/arginine 126 mutation in the French family was previously reported in a Creole ethnic group, and the Polish histidine/arginine 231 mutation was previously reported in a patient from Chicago, Moreover, all of the mutations created new restriction sites, which were used to determine the kindred carrier status in the three families. Because 5{alpha}R deficiency is known to be heterogenous disease in terms of clinical and biochemical expression, our data suggest that molecular biology analysis of the type 2 gene could be an essential step in diagnosing 5{alpha}R deficiency. 22 refs., 3 figs., 1 tab.

  5. Gender identity of children and young adults with 5alpha-reductase deficiency.

    PubMed

    Praveen, E P; Desai, Ankush K; Khurana, M L; Philip, Jim; Eunice, Marumudi; Khadgawat, Rajesh; Kulshreshtha, Bindu; Kucheria, Kiran; Gupta, Devendra K; Seith, Ashu; Ammini, Ariachery C

    2008-02-01

    Male pseudohermaphroditism (46,XY DSD) due to 5alpha-reductase deficiency has been recognized for the last few decades. There is scant literature on this entity in India. We compiled data on five patients with this disorder. Four of our five patients were reared as females. Our assessment of these children reveals that they had male gender identity from childhood. Three of the four reared as females chose to change gender role at adolescence, while the fourth is still prepubertal. We conclude that all these patients had male gender identity from early childhood. The parents took note of this only after the appearance of male secondary sexual characteristics at puberty, thereby giving an impression of change in gender identity and gender role.

  6. Battling prostate cancer with 5-alpha-reductase inhibitors: a pyrrhic victory?

    PubMed

    Hoffman, Richard M; Roberts, Richard G; Barry, Michael J

    2011-07-01

    Given the relatively small impact of prostate cancer screening on cancer mortality, experts are now suggesting that chemoprevention with 5-alpha-reductase inhibitors (5-ARI) may be a more effective strategy for cancer control. Two large placebo-controlled randomized trials found that men receiving 5-ARI were about 25% less likely than controls to be detected with cancer. However, most cancers were detected on routine biopsies required by study protocols. The benefit from receiving 5-ARI was minimal among men who underwent biopsy for clinical indications. Additionally, men receiving 5-ARI were more likely than controls to be diagnosed with high-grade cancers, though post-hoc analyses adjusting for biases accounted for the excess risk in one of the studies. A recent guideline recommended that men considering prostate cancer screening also consider chemoprevention. The rationale is that reducing cancer incidence, given the known risks for overdiagnosis and subsequent overtreatment, is sufficient justification for chemoprevention. However, a large randomized controlled trial found that screening was associated with a 70% increase in prostate cancer diagnosis--which chemoprevention would then reduce by 25%. This does not seem an acceptable trade-off especially because the potential increased risk for high-grade cancers could lead to higher cancer mortality. PMID:21222171

  7. Male pseudohermaphroditism due to steroid 5alpha-reductase 2 deficiency. Diagnosis, psychological evaluation, and management.

    PubMed

    Mendonca, B B; Inacio, M; Costa, E M; Arnhold, I J; Silva, F A; Nicolau, W; Bloise, W; Russel, D W; Wilson, J D

    1996-03-01

    Sixteen subjects (from 10 Brazilian families) with male pseudohermaphroditism due to steroid 5alpha-reductase 2 deficiency have been evaluated in 1 clinic. The diagnoses were made on the basis of normal plasma testosterone values, normal or low plasma dihydrotestosterone levels and high testosterone/dihydrotestosterone ratios in the basal state in postpubertal subjects or after treatment with either human chorionic gonadotropin or testosterone in prepubertal subjects. The analysis of the ratios of etiocholanolone to androsterone in urine confirmed the diagnosis in all subjects who were tested, and the molecular basis of the underlying mutations was established in 9 of the families. Fourteen of the individuals were evaluated by the same psychologist. All subjects but 1 were given a female sex assignment at birth. Three of the subjects (1 the sibling of an individual who has undergone female to male social behavior) maintain a female social sex; they have been gonadectomized and treated with exogenous estrogens. Ten of 13 subjects of postpubertal age underwent a change of social sex from female to male, had surgical correction of the hypospadias, and were treated with high-dose testosterone esters by parenteral injection and subsequently with dihydrotestosterone cream. These regimens brought serum dihydrotestosterone levels to the normal male range (or above) but resulted only in limited growth of the prostate and penis and, in some, increase in body and facial hair and enhancement of libido and sexual performance. Treatment of the prepubertal boys with testosterone and/or dihydrotestosterone resulted in a doubling of penis size.

  8. Synthesis of some new testosterone derivatives fused with substituted pyrazoline ring as promising 5alpha-reductase inhibitors.

    PubMed

    Amr, Abd El-Galil El-Sayed; Abdel-Latif, Nehad Ahmed; Abdalla, Mohamed Mostafa

    2006-06-01

    Condensation of 3beta-hydroxy-16-[(4-chlorophenyl)methylene]androst-5-en-17-one (1) with hydrazine hydrate in acetic acid afforded N-acetyl pyrazoline derivative 2, while condensation of 1 with semicarbazide afforded compound 3. Also, compound 1 was treated with hydrazine hydrate in absolute methanol or ethanol to afford the corresponding alpha-methoxy (4) and alpha-ethoxy (5) derivatives, which were cyclized with etherated boron trifluoride to the pyrazoline derivative 6. The latter could be prepared directly by refluxing 1 with hydrazine hydrate in dioxane. Oxidation of compound 6 with Oppenour or Moffat oxidizing agents yielded 3-oxo-derivatives 7 and 8, respectively. On the other hand, condensation of compound 1 with substituted hydrazines, gave the corresponding 3beta-hydroxyandrostenopyrazolines 9a,b, which were oxidized using the Moffat method to give 3-oxo-androstenopyrazolines 10a,b, which were condensed with ethylene triphenyl-phosphorane in DMSO to yield 3-ethylene androstenopyrazolines 11a,b. Dehydrogenation of 9a,b with Wettestein oxidation afforded Delta4,6-diene-3-one analogues 12a,b, which were treated with chloranil to yield Delta(4,6,8(14))-tri-ene-3-one analogues 13a,b. Oppenour oxidation of 9a,b afforded Delta4-ene-3-one analogues 14a,b, which were treated with dichlorodicyanoquinone (DDQ) in dioxane to give Delta1,4,6-triene-3-one analogues 15a,b. Pharmacological screening showed that many of these compounds inhibit 5alpha-reductase activity. PMID:16613726

  9. Benzo[c]quinolizin-3-ones: a novel class of potent and selective nonsteroidal inhibitors of human steroid 5alpha-reductase 1.

    PubMed

    Guarna, A; Machetti, F; Occhiato, E G; Scarpi, D; Comerci, A; Danza, G; Mancina, R; Serio, M; Hardy, K

    2000-10-01

    The synthesis and biological evaluation of a series of novel, selective inhibitors of isoenzyme 1 of human 5alpha-reductase (5alphaR) (EC 1.3.99.5) are reported. The inhibitors are 4aH- (19-29) or 1H-tetrahydrobenzo[c]quinolizin-3-ones (35-47) bearing at positions 1, 4, 5, and 6 a methyl group and at position 8 a hydrogen, methyl group, or chlorine atom. All these compounds were tested toward 5alphaR-1 and 5alphaR-2 expressed in CHO cells (CHO 1827 and CHO 1829, respectively) resulting in selective inhibitors of the type 1 isoenzyme, with inhibitory potencies (IC(50)) ranging from 7.6 to 9100 nM. The inhibitors of the 4aH-series, having a double bond at position 1,2, were generally less active than the corresponding inhibitors of the 1H-series having the double bond at position 4,4a on the A ring. The presence of a methyl group at position 4 (as in compounds 39-40 and 45-47), associated with a substituent at position 8, determined the highest inhibition potency (IC(50) from 7.6 to 20 nM). Compounds 39 and 40, having K(i) values of 5.8+/-1.8 and 2.7+/-0.6 nM, respectively, toward 5alphaR-1 expressed in CHO cells, were also tested toward native 5alphaR-1 in human scalp and 5alphaR-2 in human prostate homogenates, in comparison with finasteride and the known 5alphaR-1-selective inhibitor LY191704, and their mechanism of inhibition was determined. They both inhibited the enzyme through a reversible competitive mechanism and again were selective inhibitors of 5alphaR-1 with IC(50) values of 41 nM. These specific features make these inhibitors suitable candidates for further development as drugs in the treatment of DHT-dependent disorders such as acne and androgenic alopecia in men and hirsutism in women. PMID:11020287

  10. Enzyme-linked immunosorbent assays for doping control of 5alpha-reductase inhibitors finasteride and dutasteride.

    PubMed

    Brun, Eva M; Torres, Ana; Ventura, Rosa; Puchades, Rosa; Maquieira, Angel

    2010-06-25

    Finasteride and dutasteride are 5alpha-reductase inhibitors included in the World Anti-Doping Agency's list of banned substances. Two highly sensitive and selective ELISA assays were developed for these compounds. Polyclonal rabbit antibodies were raised using synthesized haptens and other commercial products. The best immunoassay obtained, based on an antibody-coated format, showed a limit of detection of 0.01 microg L(-1) and an IC(50) of 0.75 microg L(-1) for finasteride (cross-reactivity with dutasteride<4%). The second assay allowed finasteride and dutasteride determination, with limits of detection of 0.013 and 0.021 microg L(-1), and IC(50) values 0.18 and 1.18 microg L(-1), respectively. Both assays were highly selective to a set of anabolic steroids, but they showed 37% and 30% cross-reactivity with the major urinary metabolite of finasteride, allowing its determination. The developed ELISA had better sensitivity than HPLC/MS/MS method and was applied as a screening technique to quantify dutasteride, finasteride, and its main metabolite in human urine without sample pre-treatment. Moreover, the analysis of dutasteride's excretion urines by ELISA was used to obtain its human excretion rate, essential to improve the analytical strategies about this type of drugs (permitted as medicines and prohibited in sport) and to establish an effective anti-doping policy. PMID:20541645

  11. 5-Alpha reductase inhibitors in men with an enlarged prostate: an evaluation of outcomes and therapeutic alternatives.

    PubMed

    Naslund, Michael; Regan, Timothy S; Ong, Christine; Hogue, Susan L

    2008-05-01

    This article presents background information and highlights key findings from a managed care perspective related to enlarged prostate (EP) in Medicare-eligible patients. This article does not provide a comprehensive review of EP but instead attempts to increase the current understanding of EP through discussion of its prevalence in men aged > or =65 years, its associated economic burden, and some available treatment options. This supplement includes 3 additional articles, all of which present data from a naturalistic, managed care setting. The article by Fenter et al assesses differences in outcomes between elderly EP patients treated with finasteride and those treated with dutasteride in relation to the risks of acute urinary retention and prostate-related surgery. Issa et al conduct a comparative analysis of the combined use of alpha-blockers and 5-alpha reductase inhibitors to treat EP. The final article compares medical costs incurred within the first year of initiating treatment for EP patients receiving finasteride versus dutasteride. This supplement is intended to assist managed care formulary decision makers in evaluating key clinical and economic data that differentiate dutasteride and finasteride within the Medicare-aged population. Although the information presented is not designed to illustrate the superiority of one product over the other, it answers important questions in relation to treating EP in elderly men and raises substantial issues beyond medication costs. PMID:18611088

  12. Differential expression of steroid 5alpha-reductase isozymes and association with disease severity and angiogenic genes predict their biological role in prostate cancer.

    PubMed

    Das, Kakoli; Lorena, Pia D N; Ng, Lai Kuan; Lim, Diana; Shen, Liang; Siow, Woei Yun; Teh, Ming; Reichardt, Juergen K V; Salto-Tellez, Manuel

    2010-09-01

    The biological role of steroid 5alpha-reductase isozymes (encoded by the SRD5A1 and SRD5A2 genes) and angiogenic factors that play important roles in the pathogenesis and vascularization of prostate cancer (PC) is poorly understood. The sub-cellular expression of these isozymes and vascular endothelial growth factor (VEGF) in PC tissue microarrays (n=62) was examined using immunohistochemistry. The effect of SRD5A inhibition on the angiogenesis pathway genes in PC was also examined in prostate cell lines, LNCaP, PC3, and RWPE-1, by treating them with the SRD5A inhibitors finasteride and dutasteride, followed by western blot, quantitative PCR, and ELISA chip array techniques. In PC tissues, nuclear SRD5A1 expression was strongly associated with higher cancer Gleason scores (P=0.02), higher cancer stage (P=0.01), and higher serum prostate specific antigen (PSA) levels (P=0.01), whereas nuclear SRD5A2 expression was correlated with VEGF expression (P=0.01). Prostate tumor cell viability was significantly reduced in dutasteride-treated PC3 and RWPE-1 cells compared with finasteride-treated groups. Expression of the angiogenesis pathway genes transforming growth factor beta 1 (TGFB1), endothelin (EDN1), TGFalpha (TGFA), and VEGFR1 was upregulated in LNCaP cells, and at least 7 out of 21 genes were upregulated in PC3 cells treated with finasteride (25 muM). Our findings suggest that SRD5A1 expression predominates in advanced PC, and that inhibition of SRD5A1 and SRD5A2 together was more effective in reducing cell numbers than inhibition of SRD5A2 alone. However, these inhibitors did not show any significant difference in prostate cell angiogenic response. Interestingly, some angiogenic genes remained activated after treatment, possibly due to the duration of treatment and tumor resistance to inhibitors. PMID:20519274

  13. The effect of 5alpha-reductase inhibition with finasteride and dutasteride on bone mineral density in older men with benign prostatic hyperplasia.

    PubMed

    Mačukat, Indira Radin; Spanjol, Josip; Orlič, Zeljka Crncevič; Butorac, Marta Zuvič; Marinovič, Marin; Ćupič, Dora Fučkar

    2014-09-01

    Testosterone is converted to dihyrotestosterone by two isoenzymes of 5alpha-reductase. Finasteride and dutasteride are 5alpha-reductase inhibitors commonly used in the treatment of benign prostatic hyperplasia. We compared indices of bone mineral density in 50 men treated with finasteride, 50 men treated with dutasteride and 50 men as control. Bone mineral density of spine and hip were measured using dual energy X-ray absorptiometry. Bone formation was assessed by measuring serum osteocalcin and bone resorptionby measuring serum C-terminal telopeptide of collagen type 1. In addition serum total testosteron and estradiol were determined. The dutasteride group had significantly higher mean bone min- eral density, mean bone mineral content, mean T score, mean Z score at femoral neck and mean total hip Z score than control. Mean total testosterone and estradiol levels were higher in the dutasteride group. There were no significant dif- ferences between the groups in lumbar spine bone density parameters or bone turnover markers. Our results provide evidence that long-term 5alpha-reductase suppression does not adversely affect bone mineral density. Dutasteride therapy could have beneficial effect on bone density. PMID:25507347

  14. The effect of 5alpha-reductase inhibition with finasteride and dutasteride on bone mineral density in older men with benign prostatic hyperplasia.

    PubMed

    Mačukat, Indira Radin; Spanjol, Josip; Orlič, Zeljka Crncevič; Butorac, Marta Zuvič; Marinovič, Marin; Ćupič, Dora Fučkar

    2014-09-01

    Testosterone is converted to dihyrotestosterone by two isoenzymes of 5alpha-reductase. Finasteride and dutasteride are 5alpha-reductase inhibitors commonly used in the treatment of benign prostatic hyperplasia. We compared indices of bone mineral density in 50 men treated with finasteride, 50 men treated with dutasteride and 50 men as control. Bone mineral density of spine and hip were measured using dual energy X-ray absorptiometry. Bone formation was assessed by measuring serum osteocalcin and bone resorptionby measuring serum C-terminal telopeptide of collagen type 1. In addition serum total testosteron and estradiol were determined. The dutasteride group had significantly higher mean bone min- eral density, mean bone mineral content, mean T score, mean Z score at femoral neck and mean total hip Z score than control. Mean total testosterone and estradiol levels were higher in the dutasteride group. There were no significant dif- ferences between the groups in lumbar spine bone density parameters or bone turnover markers. Our results provide evidence that long-term 5alpha-reductase suppression does not adversely affect bone mineral density. Dutasteride therapy could have beneficial effect on bone density. PMID:25420363

  15. Micropenis and the 5alpha-reductase-2 (SRD5A2) gene: mutation and V89L polymorphism analysis in 81 Japanese patients.

    PubMed

    Sasaki, Goro; Ogata, Tsutomu; Ishii, Tomohiro; Kosaki, Kenjiro; Sato, Seiji; Homma, Keiko; Takahashi, Takao; Hasegawa, Tomonobu; Matsuo, Nobutake

    2003-07-01

    The 5alpha-reductase-2 encoded by the SRD5A2 gene plays a critical role in male sex differentiation by converting testosterone into 5alpha dihydrotestosterone in the peripheral target tissues. In this study, we examined the SRD5A2 gene in 81 Japanese patients with micropenis (age, 0-14 yr; median, 7 yr) whose stretched penile lengths were between -2.5 SD and -2.0 SD in 39 patients (age, 0-13 yr; median, 8 yr) and below -2.5 SD in 42 patients (age, 0-14 yr; median, 6 yr), together with 100 control males (50 boys and 50 fertile adult males). Mutation analysis was performed for exons 1-5 and their flanking introns by denaturing HPLC and direct sequencing, revealing Y26X/R227Q in an 11-yr-old boy with a penile length of -2.6 SD, G34R/R227Q in a 9-yr-old boy with a penile length of -3.6 SD, and R227Q/R227Q in a 3-yr-old boy with a penile length of -2.4 SD, together with heterozygous R227Q in a control boy and a fertile adult male. Polymorphism analysis was carried out for the most frequent V89L known to reduce the enzyme activity by approximately 30% in 78 patients, except for the three patients with SRD5A2 mutations, and in the 100 control males by direct sequencing, showing that allele and genotype frequencies were similar between 78 patients with micropenis below -2.0 SD or 40 patients with micropenis below -2.5 SD and the 100 control males, the 50 boys, or the 50 fertile adult males, with no statistically significant differences. The results suggest that, in Japanese patients, micropenis can be caused by SRD5A2 gene mutations, especially by R227Q which has been shown to retain approximately 3.2% of normal enzyme activity and appears relatively frequent in Asian populations, and that V89L polymorphism is unlikely to raise the susceptibility to the development of micropenis.

  16. Selective induction of apoptosis in the hamster flank sebaceous gland organ by a topical liposome 5-alpha-reductase inhibitor: a treatment strategy for acne.

    PubMed

    Li, Lingna; Tang, Li; Baranov, Eugene; Yang, Meng; Amoh, Yasuyuki; Katsuoka, Kensei; Hoffman, Robert M

    2010-02-01

    Acne is a very widespread cosmesis problem. Isotretinoin, a synthetic oral retinoid is used to treat acne, which is androgen dependent. Numerous side-effects occur from this treatment. 5-alpha-Reductase plays a critical role in normal and pathological androgen-dependent processes. We have taken the approach to develop a selective, effective, topically-applied 5-alpha-reductase inhibitor to modify unwanted or pathological processes in the pilosebaceous unit such as acne. Toward this goal, we have previously developed a selective liposome hair follicle targeting system. We demonstrate in this report that the 5-alpha-reductase inhibitor N,N-diethyl-4-methyl-3-oxo-4-aza-5alpha-androstane-17beta-carboxamide (4-MA) incorporated into liposomes induces apoptosis and inhibits growth of the dihydrotestosterone (DHT)-dependent hamster flank organ sebaceous gland. We have compared topical application of liposome 4-MA and solvent-formulated 4-MA and observed selective efficacy of topical application of liposome 4-MA by the reduction of size and induction of apoptosis only in the treated hamster flank organ. Apoptosis induced by liposome 4-MA in the treated flank organ sebaceous gland cells was observed both by assays for DNA fragments (transferase deoxytidyl uridine end labeling) and by observation of condensed and fragmented nuclei. When 4-MA was topically applied formulated in ethanol and glycerol without liposomes, the selective efficacy was lost. Liposome 4-MA did not significantly affect prostate weight, testosterone/DHT ratios or bodyweight gain compared to controls indicating safety as well as efficacy of topical application of liposome 4-MA for pathological processes such as acne. PMID:20175850

  17. The role of 5-alpha reductase inhibitors in prostate pathophysiology: Is there an additional advantage to inhibition of type 1 isoenzyme?

    PubMed

    Goldenberg, Larry; So, Alan; Fleshner, Neil; Rendon, Ricardo; Drachenberg, Darrel; Elhilali, Mostafa

    2009-06-01

    Normal growth and function of the prostate are contingent on the reduction of testosterone to dihydrotestosterone (DHT) by 5-alpha reductase (5-AR) enzymes types 1 and 2. It has been theorized that an overabundance of DHT may be implicated in the pathogenesis of both benign prostatic hyperplasia (BPH) and prostate cancer. Inhibitors of 5-AR such as dutasteride and finasteride may therefore have an important role in the prevention and treatment of BPH and prostate cancer. Dutasteride provides greater suppression of DHT than finasteride, thereby underlying the hypothesis that inhibition of both type 1 and type 2 would provide correspondingly greater protection than inhibition of type 2 alone. We review the potential significance of the 5-AR inhibitors in reducing the risk of prostate cancer according to the basic biology of prostate disease. PMID:19543428

  18. Reprint of "Current perspectives on the androgen 5 alpha-dihydrotestosterone (DHT) and 5 alpha-reductases in teleost fishes and amphibians".

    PubMed

    Martyniuk, Christopher J; Bissegger, Sonja; Langlois, Valérie S

    2014-07-01

    The androgen 5 alpha-dihydrotestosterone (DHT) is a steroidogenic metabolite that has received little attention in non-mammalian species. DHT is produced by the reduction of the double-bond of testosterone by a group of enzymes called 5 alpha-reductases of which there can be multiple isoforms (i.e., srd5a1, srd5a2, and srd5a3). Data from amphibians suggest that the expression of the srd5a genes occurs in early development, and continues until adulthood; however insufficient data exist in fish species, where DHT is thought to be relatively biologically inactive. Here, we demonstrate that fathead minnow (FHM; Pimephales promelas) developing embryos and adults express srd5a enzyme isoforms. During FHM embryogenesis, both srd5a1 and srd5a3 mRNA levels were significantly correlated in expression levels while srd5a2 showed a more unique pattern of expression. In adult FHMs, males had significantly higher levels of srd5a2 in the liver and gonad compared to females. In the male and female liver, transcript levels for srd5a2 were more abundant compared to srd5a1 and srd5a3, suggesting a prominent role for srd5a2 in this tissue. Interestingly, the ovary expressed higher mRNA levels of srd5a3 than the testis. Thus, data suggest that srd5a isoforms can show sexually dimorphic expression patterns in fish. We also conducted a literature review of the biological effects observed in embryonic and adult fish and amphibians after treatments with DHT and DHT-related compounds. Treatments with DHT in teleost fishes and amphibians have resulted in unexpected biological responses that are characteristic of both androgens and anti-androgens. For example, in fish DHT can induce vitellogenin in vitro from male and female hepatocytes and can increase 17β-estradiol production from the teleost ovary. We propose, that to generate further understanding of the roles of DHT in non-mammals, studies are needed that (1) address how DHT is synthesized within tissues of fish and amphibians; (2

  19. MK-386, an inhibitor of 5alpha-reductase type 1, reduces dihydrotestosterone concentrations in serum and sebum without affecting dihydrotestosterone concentrations in semen.

    PubMed

    Schwartz, J I; Tanaka, W K; Wang, D Z; Ebel, D L; Geissler, L A; Dallob, A; Hafkin, B; Gertz, B J

    1997-05-01

    Two isozymes (types 1 and 2) of 5alpha-reductase (5alphaR; EC 1.3.99.5), with differential tissue distribution, catalyze the reduction of testosterone (T) to dihydrotestosterone (DHT) in humans. This study examined sequentially increasing oral doses of MK-386 (4,7beta-dimethyl-4-aza-5alpha-cholestan-3-one), an azasteroid that specifically inhibits the human 5alphaR1 isozyme in vitro. Finasteride, a selective inhibitor of 5alphaR2, was included for comparison. One hundred men were evaluated in a double blind, randomized, placebo-controlled, sequential, increasing dose, parallel group trial. Ten to 20 subjects received MK-386, and 2 to 5 received placebo in each of 6 panels. In 1 panel, 10 subjects received finasteride (5 mg), and 5 received placebo. Treatments were given once daily for 14 days, except in 1 panel in which MK-386 was administered 10 mg twice daily for comparison to 20 mg daily. Serum, sebum, and semen DHT concentrations and serum and sebum T concentrations were measured before and after treatment. The mean changes from baseline on day 14 for serum DHT after placebo and 0.1, 0.5, 5, 20, and 50 mg MK-386 were 6.9%, 4.6%, -2.7%, -1.2%, -14.1% (P < 0.05 vs. placebo), and -22.2% (P < 0.05 vs. placebo), respectively. No significant alterations in serum T were observed after any dose of MK-386. Serum DHT fell 65.8% from the baseline 14 days after finasteride treatment (P < 0.05 vs. placebo). The mean changes from baseline on day 14 in sebum DHT were 5.0%, 3.0%, -25.4% (P < 0.05 vs. placebo), -30.1% (P < 0.05 vs. placebo), and -49.1% (P < 0.05 vs. placebo) for the placebo and 0.5, 5, 20, and 50 mg MK-386 groups, respectively. Finasteride also reduced sebum DHT, but to a lesser extent (- 14.9%; P < 0.05 vs. placebo). Reciprocal increases in sebum T concentration were noted at doses of 5 mg or more of MK-386, but not with finasteride. The mean reduction in semen DHT with 5 mg finasteride was approximately 88% (P < 0.01 vs. placebo); no significant change in

  20. Mode of action of human pharmaceuticals in fish: the effects of the 5-alpha-reductase inhibitor, dutasteride, on reproduction as a case study.

    PubMed

    Margiotta-Casaluci, Luigi; Hannah, Robert E; Sumpter, John P

    2013-03-15

    In recent years, a growing number of human pharmaceuticals have been detected in the aquatic environment, generally at low concentrations (sub-ng/L-low μg/L). In most cases, these compounds are characterised by highly specific modes of action, and the evolutionary conservation of drug targets in wildlife species suggests the possibility that pharmaceuticals present in the environment may cause toxicological effects by acting through the same targets as they do in humans. Our research addressed the question of whether or not dutasteride, a pharmaceutical used to treat benign prostatic hyperplasia, may cause adverse effects in a teleost fish, the fathead minnow (Pimephales promelas), by inhibiting the activity of both isoforms of 5α-reductase (5αR), the enzyme that converts testosterone into dihydrotestosterone (DHT). Mammalian pharmacological and toxicological information were used to guide the experimental design and the selection of relevant endpoints, according to the so-called "read-across approach", suggesting that dutasteride may affect male fertility and steroid hormone dynamics. Therefore, a 21-day reproduction study was conducted to determine the effects of dutasteride (10, 32 and 100 μg/L) on fish reproduction. Exposure to dutasteride significantly reduced fecundity of fish and affected several aspects of reproductive endocrine functions in both males and females. However, none of the observed adverse effects occurred at concentrations of exposure lower than 32 μg/L; this, together with the low volume of drug prescribed every year (10.34 kg in the UK in 2011), and the extremely low predicted environmental concentration (0.03 ng/L), suggest that, at present, the potential presence of dutasteride in the environment does not represent a threat to wild fish populations. PMID:23280489

  1. Lipoxygenase inhibitory activity of alkyl protocatechuates.

    PubMed

    Ha, Tae Joung; Shimizu, Kuniyoshi; Kubo, Isao

    2014-09-15

    Alkyl 3,4-dihydroxybenzoates (protocatechuates) inhibited linoleic acid peroxidation catalyzed by soybean lipoxygenase-1 (EC 1.13.11.12, Type 1). Their inhibitory activities displayed a parabolic function of their lipophilicity and maximized with alkyl chain lengths of between C11 and C14. Tetradecanyl protocatechuate exhibited the most potent inhibition with an IC50 of 0.05 μM, followed by dodecyl (lauryl) protocatechuate with an IC50 of 0.06 μM. However, their parent compound, protocatechuic acid, did not show this inhibitory activity up to 200 μM, indicating that the alkyl chain length is significantly related to the inhibition activity. The allosteric (or cooperative) inhibition of soybean lipoxygenase-1 of longer alkyl protocatechuates is reversible but in combination with their iron binding ability to disrupt the active site competitively and to interact with the hydrophobic portion surrounding near the active site (sequential action). In the case of dodecyl protocatechuate, the enzyme quickly binds this protocatechuate and then its dodecyl group undergoes a slow interaction with the hydrophobic domain in close proximity to the active site in the enzyme. The inhibition kinetics analyzed by Lineweaver-Burk plots indicates that octyl protocatechuate is a competitive inhibitor and the inhibition constant (Ki) was obtained as 0.23 μM but dodecyl protocatechuate is a slow binding inhibitor.

  2. Monoamine oxidase inhibitory activities of heterocyclic chalcones.

    PubMed

    Minders, Corné; Petzer, Jacobus P; Petzer, Anél; Lourens, Anna C U

    2015-11-15

    Studies have shown that natural and synthetic chalcones (1,3-diphenyl-2-propen-1-ones) possess monoamine oxidase (MAO) inhibition activities. Of particular importance to the present study is a report that a series of furanochalcones acts as MAO-B selective inhibitors. Since the effect of heterocyclic substitution, other than furan (and more recently thiophene, piperidine and quinoline) on the MAO inhibitory properties of the chalcone scaffold remains unexplored, the aim of this study was to synthesise and evaluate further heterocyclic chalcone analogues as inhibitors of the human MAOs. For this purpose, heterocyclic chalcone analogues that incorporate pyrrole, 5-methylthiophene, 5-chlorothiophene and 6-methoxypyridine substitution were examined. Seven of the nine synthesised compounds exhibited IC50 values <1 μM for the inhibition of MAO-B, with all compounds exhibiting higher affinities for MAO-B compared to the MAO-A isoform. The most potent MAO-B inhibitor (4h) displays an IC50 value of 0.067 μM while the most potent MAO-A inhibitor (4e) exhibits an IC50 value of 3.81 μM. It was further established that selected heterocyclic chalcones are reversible and competitive MAO inhibitors. 4h, however, may exhibit tight-binding to MAO-B, a property linked to its thiophene moiety. We conclude that high potency chalcones such as 4h represent suitable leads for the development of MAO-B inhibitors for the treatment of Parkinson's disease and possibly other neurodegenerative disorders.

  3. Xanthine oxidase inhibitory activity of Hungarian wild-growing mushrooms.

    PubMed

    Ványolós, Attila; Orbán-Gyapai, Orsolya; Hohmann, Judit

    2014-08-01

    Mushrooms represent a remarkable and yet largely unexplored source of new, biologically active natural products. In this work, we report on the xanthine oxidase (XO) inhibitory activity of 47 wild-growing mushrooms native to Hungary. Aqueous and organic (n-hexane, chloroform, and 50% methanol) extracts of selected mushrooms from different families were screened for their XO inhibitory activities. Among the 188 extracts investigated, the chloroform and 50% methanol fractions proved to be the most effective. Some species exhibited high inhibitory activity, e.g., Hypholoma fasciculare (IC50  =67.76 ± 11.05 µg/mL), Suillus grevillei (IC50  =13.28 ± 1.58 µg/mL), and Tricholoma populinum (IC50  =85.08 ± 15.02 µg/mL); others demonstrated moderate or weak activity. Additional studies are warranted to characterize the compounds responsible for the XO inhibitory activity of mushroom extracts.

  4. Antioxidative/acetylcholinesterase inhibitory activity of some Asteraceae plants.

    PubMed

    Mekinić, Ivana Generalić; Burcul, Franko; Blazević, Ivica; Skroza, Danijela; Kerum, Daniela; Katalinić, Visnja

    2013-04-01

    The extracts obtained by 80% EtOH from some Asteraceae plants (Calendula officinalis, Inula helenium, Arctium lappa, Artemisia absinthium and Achillea millefolium) were studied. Rosmarinic acid, one of the main compounds identified in all extracts, was determined quantitatively by using HPLC. In addition, spectrophotometric methods were evaluated as an alternative for rosmarinic acid content determination. Total phenolic content was also established for all extracts. A. millefolium extract was found to have the highest content of rosmarinic acid as well as total phenols. All extracts were tested for antioxidant and acetylcholinesterase inhibitory activity. A. millefolium was shown to possess the best antioxidant activity (for all tested methods) as well as acetylcholinesterase inhibitory activity. Highly positive linear relationships were obtained between antioxidant/acetylcholinesterase inhibitory activity and the determined rosmarinic acid content indicating its significance for the observed activities. PMID:23738456

  5. Serum chemotactic inhibitory activity: heat activation of chemotactic inhibition.

    PubMed Central

    Epps, D E; Williams, R C

    1976-01-01

    Serum chemotactic inhibitory activity (CIA) was studied in 46 patients with various systemic diseases, using a system consisting of normal human leukocytes as indicator cells and 10% fresh normal serum as a control chemotactic attractant. It was shown, as previously reported, that an association exists between CIA and skin test anergy. Heat treatment of sera at 56 C for 30 min increased both the incidence and the degree of chemotactic inhibition observed in these patients. The effects of heat treatment of sera containing CIA on other chemotactic attractants (C3a, bacteria-derived chemotactic factor (BF), and casein) are shown. Before heat treatment, some sera suppressed chemotaxis mediated by BF in the absence of suppression of normal serum-mediated chemotaxis, indicating the possible involvement of more than one system of inhibition. Multiple systems were further supported by data indicating that room temperature incubation resulted in a loss of CIA as measured by normal serum-mediated chemotoxis with no apparent decrease in the inhibition of BF -mediated chemotaxis. Separation of sera containing CIA by Sephadex G-200 showed chemotactic inhibitory activity to be increased in both the void volume region. Experiments showed that heat treating before separation resulted in similar increases in both peaks, implying the presence of an antagonist to CIA. Experiments demonstrating that sera containing CIA do not suppress casein-mediated chemotaxis by means of an irreversible inactivation of chemotactic factor are included along with experiments demonstrating a cellular mode of action. The possible presence of two systems of chemotactic inhibition, one acting directly upon chemotactic factors and one interacting with the responding cell, are discussed. PMID:773824

  6. Xanthine oxidase inhibitory activity of Vietnamese medicinal plants.

    PubMed

    Nguyen, Mai Thanh Thi; Awale, Suresh; Tezuka, Yasuhiro; Tran, Quan Le; Watanabe, Hiroshi; Kadota, Shigetoshi

    2004-09-01

    Among 288 extracts, prepared from 96 medicinal plants used in Vietnamese traditional medicine to treat gout and related symptoms, 188 demonstrated xanthine oxidase (XO) inhibitory activity at 100 microg/ml, with 46 having greater than 50% inhibition. At 50 microg/ml, 168 of the extracts were active, with 21 possessing more than 50% inhibition. At 25 microg/ml, 146 extracts exhibited inhibitory activity, with 8 showing over 50% inhibition, while 126 extracts presented activity at 10 microg/ml, with 2 having greater than 50% inhibition. The MeOH extracts of Artemisia vulgaris, Caesalpinia sappan (collected at the Seven-Mountain area), Blumea balsamifera (collected in Lam Dong province), Chrysanthemum sinense and MeOH-H(2)O extract of Tetracera scandens (Khanh Hoa province) exhibited strong XO inhibitory activity with IC(50) values less than 20 microg/ml. The most active extract was the MeOH extract of the flower of C. sinense with an IC(50) value of 5.1 microg/ml. Activity-guided fractionation of the MeOH extract led to the isolation of caffeic acid (1), luteolin (2), eriodictyol (3), and 1,5-di-O-caffeoylquinic acid (4). All these compounds showed significant XO inhibitory activity in a concentration-dependent manner, and the activity of 2 was more potent (IC(50) 1.3 microM) than the clinically used drug, allopurinol (IC(50) 2.5 microM). PMID:15340229

  7. Decorrelation of Neural-Network Activity by Inhibitory Feedback

    PubMed Central

    Einevoll, Gaute T.; Diesmann, Markus

    2012-01-01

    Correlations in spike-train ensembles can seriously impair the encoding of information by their spatio-temporal structure. An inevitable source of correlation in finite neural networks is common presynaptic input to pairs of neurons. Recent studies demonstrate that spike correlations in recurrent neural networks are considerably smaller than expected based on the amount of shared presynaptic input. Here, we explain this observation by means of a linear network model and simulations of networks of leaky integrate-and-fire neurons. We show that inhibitory feedback efficiently suppresses pairwise correlations and, hence, population-rate fluctuations, thereby assigning inhibitory neurons the new role of active decorrelation. We quantify this decorrelation by comparing the responses of the intact recurrent network (feedback system) and systems where the statistics of the feedback channel is perturbed (feedforward system). Manipulations of the feedback statistics can lead to a significant increase in the power and coherence of the population response. In particular, neglecting correlations within the ensemble of feedback channels or between the external stimulus and the feedback amplifies population-rate fluctuations by orders of magnitude. The fluctuation suppression in homogeneous inhibitory networks is explained by a negative feedback loop in the one-dimensional dynamics of the compound activity. Similarly, a change of coordinates exposes an effective negative feedback loop in the compound dynamics of stable excitatory-inhibitory networks. The suppression of input correlations in finite networks is explained by the population averaged correlations in the linear network model: In purely inhibitory networks, shared-input correlations are canceled by negative spike-train correlations. In excitatory-inhibitory networks, spike-train correlations are typically positive. Here, the suppression of input correlations is not a result of the mere existence of correlations between

  8. Xanthine oxidase inhibitory activity of alkyl gallates.

    PubMed

    Masuoka, Noriyoshi; Nihei, Ken-ichi; Kubo, Isao

    2006-08-01

    A series (C1-C12) of alkyl gallates was examined for their effects on the activity of xanthine oxidase. Octyl (C8), decyl (C10), and dodecyl (C12) gallates competitively inhibited uric acid formation generated by xanthine oxidase, and the inhibition increased upon increasing the alkyl chain length. Interestingly, neither menthyl nor bornyl gallates inhibited uric acid formation. These data indicate that the hydrophobic alkyl portion is associated with the xanthine-binding site in the Mo-binding domain. It is likely that the linear alkyl portion interacts with the hydrophobic domain close to the binding site, and the hydrophobic interaction is crucial to inhibit the xanthine oxidase reaction. On the other hand, all of gallic acid and its esters equally suppress superoxide anion generation catalyzed by xanthine oxidase at low concentration. The suppression is not due to scavenging activity of these gallates but due to reduction of xanthine oxidase by these gallates. The reduced enzyme catalyzes the reaction to generate hydrogen peroxide and uric acid.

  9. Dihydroasparagusic acid: antioxidant and tyrosinase inhibitory activities and improved synthesis.

    PubMed

    Venditti, Alessandro; Mandrone, Manuela; Serrilli, Anna Maria; Bianco, Armandodoriano; Iannello, Carmelina; Poli, Ferruccio; Antognoni, Fabiana

    2013-07-17

    Dihydroasparagusic acid (DHAA) is the reduced form of asparagusic acid, a sulfur-containing flavor component produced by Asparagus plants. In this work, DHAA was synthetically produced by modifying some published protocols, and the synthesized molecule was tested in several in vitro assays (DPPH, ABTS, FRAP-ferrozine, BCB, deoxyribose assays) to evaluate its radical scavenging activity. Results show that DHAA is endowed with a significant in vitro antioxidant activity, comparable to that of Trolox. DHAA was also evaluated for its inhibitory activity toward tyrosinase, an enzyme involved, among others, in melanogenesis and in browning processes of plant-derived foods. DHAA was shown to exert an inhibitory effect on tyrosinase activity, and the inhibitor kinetics, analyzed by a Lineweaver-Burk plot, exhibited a competitive mechanism. Taken together, these results suggest that DHAA may be considered as a potentially active molecule for use in various fields of application, such as pharmaceutical, cosmetics, agronomic and food. PMID:23790134

  10. Phenolic compounds with IL-6 inhibitory activity from Aster yomena.

    PubMed

    Kim, A Ryun; Jin, Qinglong; Jin, Hong-Guang; Ko, Hae Ju; Woo, Eun-Rhan

    2014-07-01

    A new biflavonoid, named asteryomenin (1), as well as six known phenolic compounds, esculetin (2), 4-O-β-D-glucopyranoside-3-hydroxy methyl benzoate (3), caffeic acid (4), isoquercitrin (5), isorhamnetin-3-O-glucoside (6), and apigenin (7) were isolated from the aerial parts of Aster yomena. The structures of compounds (1-7) were identified based on 1D and 2D NMR, including (1)H-(1)H COSY, HSQC, HMBC and NOESY spectroscopic analyses. Compounds 2-7 were isolated from this plant for the first time. For these isolates, the inhibitory activity of IL-6 production in the TNF-α stimulated MG-63 cell was examined. Among these isolates, compounds 4 and 7 appeared to have potent inhibitory activity of IL-6 production in the TNF-α stimulated MG-63 cell, while compounds 1-3 and 5-6 showed moderate activity.

  11. Urease inhibitory activities of β-boswellic acid derivatives

    PubMed Central

    2013-01-01

    Background and the purpose of the study Boswellia carterii have been used in traditional medicine for many years for management different gastrointestinal disorders. In this study, we wish to report urease inhibitory activity of four isolated compound of boswellic acid derivative. Methods 4 pentacyclic triterpenoid acids were isolated from Boswellia carterii and identified by NMR and Mass spectroscopic analysis (compounds 1, 3-O-acetyl-9,11-dehydro-β-boswellic acid; 2, 3-O-acetyl-11-hydroxy-β-boswellic acid; 3. 3-O- acetyl-11-keto-β-boswellic acid and 4, 11-keto-β-boswellic acid. Their inhibitory activity on Jack bean urease were evaluated. Docking and pharmacophore analysis using AutoDock 4.2 and Ligandscout 3.03 programs were also performed to explain possible mechanism of interaction between isolated compounds and urease enzyme. Results It was found that compound 1 has the strongest inhibitory activity against Jack bean urease (IC50 = 6.27 ± 0.03 μM), compared with thiourea as a standard inhibitor (IC50 = 21.1 ± 0.3 μM). Conclusion The inhibition potency is probably due to the formation of appropriate hydrogen bonds and hydrophobic interactions between the investigated compounds and urease enzyme active site and confirms its traditional usage. PMID:23351363

  12. Potential xanthine oxidase inhibitory activity of endophytic Lasiodiplodia pseudotheobromae.

    PubMed

    Kapoor, Neha; Saxena, Sanjai

    2014-07-01

    Xanthine oxidase is considered as a potential target for treatment of hyperuricemia. Hyperuricemia is predisposing factor for gout, chronic heart failure, atherosclerosis, tissue injury, and ischemia. To date, only two inhibitors of xanthine oxidase viz. allopurinol and febuxostat have been clinically approved for used as drugs. In the process of searching for new xanthine oxidase inhibitors, we screened culture filtrates of 42 endophytic fungi using in vitro qualitative and quantitative XO inhibitory assays. The qualitative assay exhibited potential XO inhibition by culture filtrates of four isolates viz. #1048 AMSTITYEL, #2CCSTITD, #6AMLWLS, and #96 CMSTITNEY. The XO inhibitory activity was present only in the chloroform extract of the culture filtrates. Chloroform extract of culture filtrate #1048 AMSTITYEL exhibited the highest inhibition of XO with an IC50 value of 0.61 μg ml(-1) which was better than allopurinol exhibiting an IC50 of 0.937 μg ml(-1) while febuxostat exhibited a much lower IC50 of 0.076 μg ml(-1). Further, molecular phylogenetic tools and morphological studies were used to identify #1048 AMSTITYEL as Lasiodiplodia pseudotheobromae. This is the first report of an endophytic Lasiodiplodia pseudotheobromae from Aegle marmelos exhibiting potential XO Inhibitory activity.

  13. Histamine release inhibitory activity of Piper nigrum leaf.

    PubMed

    Hirata, Noriko; Naruto, Shunsuke; Inaba, Kazunori; Itoh, Kimihisa; Tokunaga, Masashi; Iinuma, Munekazu; Matsuda, Hideaki

    2008-10-01

    Oral administration of a methanolic extract of Piper nigrum leaf (PN-ext, 50, 200 and 500 mg/kg) showed a potent dose-dependent inhibition of dinitrofluorobenzene (DNFB)-induced cutaneous reaction at 1 h [immediate phase response (IPR)] after and 24 h [late phase response (LPR)] after DNFB challenge in mice which were passively sensitized with anti-dinitrophenyl (DNP) IgE antibody. Ear swelling inhibitory effect of PN-ext (50, 200 and 500 mg/kg, per os (p.o.)) on very late phase response (vLPR) in the model mice was significant but weaker than that on IPR. Oral administration of PN-ext (50, 200 and 500 mg/kg for 7 d) inhibited picryl chloride (PC)-induced ear swelling in PC sensitized mice. PN-ext exhibited in vitro inhibitory effect on compound 48/80-induced histamine release from rat peritoneal mast cells. Two lignans of PN-ext, (-)-cubebin (1) and (-)-3,4-dimethoxy-3,4-desmethylenedioxycubebin (2), were identified as major active principles having histamine release inhibitory activity.

  14. Potential xanthine oxidase inhibitory activity of endophytic Lasiodiplodia pseudotheobromae.

    PubMed

    Kapoor, Neha; Saxena, Sanjai

    2014-07-01

    Xanthine oxidase is considered as a potential target for treatment of hyperuricemia. Hyperuricemia is predisposing factor for gout, chronic heart failure, atherosclerosis, tissue injury, and ischemia. To date, only two inhibitors of xanthine oxidase viz. allopurinol and febuxostat have been clinically approved for used as drugs. In the process of searching for new xanthine oxidase inhibitors, we screened culture filtrates of 42 endophytic fungi using in vitro qualitative and quantitative XO inhibitory assays. The qualitative assay exhibited potential XO inhibition by culture filtrates of four isolates viz. #1048 AMSTITYEL, #2CCSTITD, #6AMLWLS, and #96 CMSTITNEY. The XO inhibitory activity was present only in the chloroform extract of the culture filtrates. Chloroform extract of culture filtrate #1048 AMSTITYEL exhibited the highest inhibition of XO with an IC50 value of 0.61 μg ml(-1) which was better than allopurinol exhibiting an IC50 of 0.937 μg ml(-1) while febuxostat exhibited a much lower IC50 of 0.076 μg ml(-1). Further, molecular phylogenetic tools and morphological studies were used to identify #1048 AMSTITYEL as Lasiodiplodia pseudotheobromae. This is the first report of an endophytic Lasiodiplodia pseudotheobromae from Aegle marmelos exhibiting potential XO Inhibitory activity. PMID:24801403

  15. Angiotensin-converting enzyme inhibitory activity in Mexican Fresco cheese.

    PubMed

    Torres-Llanez, M J; González-Córdova, A F; Hernandez-Mendoza, A; Garcia, H S; Vallejo-Cordoba, B

    2011-08-01

    The objective of this study was to evaluate if Mexican Fresco cheese manufactured with specific lactic acid bacteria (LAB) presented angiotensin I-converting enzyme inhibitory (ACEI) activity. Water-soluble extracts (3 kDa) obtained from Mexican Fresco cheese prepared with specific LAB (Lactococcus, Lactobacillus, Enterococcus, and mixtures: Lactococcus-Lactobacillus and Lactococcus-Enterococcus) were evaluated for ACEI activity. Specific peptide fractions with high ACEI were analyzed using reverse phase-HPLC coupled to mass spectrometry for determination of amino acid sequence. Cheese containing Enterococcus faecium or a Lactococcus lactis ssp. lactis-Enterococcus faecium mixture showed the largest number of fractions with ACEI activity and the lowest half-maximal inhibitory concentration (IC(50); <10 μg/mL). Various ACEI peptides derived from β-casein [(f(193-205), f(193-207), and f(193-209)] and α(S1)-casein [f(1-15), f(1-22), f(14-23), and f(24-34)] were found. The Mexican Fresco cheese manufactured with specific LAB strains produced peptides with potential antihypertensive activity.

  16. Anticholinesterase inhibitory activity of quaternary alkaloids from Tinospora crispa.

    PubMed

    Yusoff, Mashitah; Hamid, Hazrulrizawati; Houghton, Peter

    2014-01-01

    Quaternary alkaloids are the major alkaloids isolated from Tinospora species. A previous study pointed to the necessary presence of quaternary nitrogens for strong acetylcholinesterase (AChE) inhibitory activity in such alkaloids. Repeated column chromatography of the vine of Tinospora crispa extract led to the isolation of one new protoberberine alkaloid, 4,13-dihydroxy-2,8,9-trimethoxydibenzo[a,g]quinolizinium (1), along with six known alkaloids-dihydrodiscretamine (2), columbamine (3), magnoflorine (4), N-formylannonaine (5), N-formylnornuciferine (6), and N-trans-feruloyltyramine (7). The seven compounds were isolated and structurally elucidated by spectroscopic analysis. Two known alkaloids, namely, dihydrodiscretamine and columbamine are reported for the first time for this plant. The compounds were tested for AChE inhibitory activity using Ellman's method. In the AChE inhibition assay, only columbamine (3) showed strong activity with IC50 48.1 µM. The structure-activity relationships derived from these results suggest that the quaternary nitrogen in the skeleton has some effect, but that a high degree of methoxylation is more important for acetylcholinesterase inhibition. PMID:24448061

  17. Xanthine oxidase inhibitory activity of extracts prepared from Polygonaceae species.

    PubMed

    Orbán-Gyapai, Orsolya; Lajter, Ildikó; Hohmann, Judit; Jakab, Gusztáv; Vasas, Andrea

    2015-03-01

    The xanthine oxidase (XO) inhibitory activity of aqueous and organic extracts of 27 selected species belonging in five genera (Fallopia, Oxyria, Persicaria, Polygonum and Rumex) of the family Polygonaceae occurring in the Carpathian Basin were tested in vitro. From different plant parts (aerial parts, leaves, flowers, fruits and roots), a total of 196 extracts were prepared by subsequent extraction with methanol and hot H2O and solvent-solvent partition of the MeOH extract yielding n-hexane, chloroform and 50% MeOH subextracts. It was found that the chloroform subextracts and/or the remaining 50% MeOH extracts of Fallopia species (F. bohemica, F. japonica and F. sachalinensis), Rumex species (R. acetosa, R. acetosella, R. alpinus, R. conglomeratus, R. crispus, R. hydrolapathus, R. pulcher, R. stenophyllus, R. thyrsiflorus, R. obtusifolius subsp. subalpinus, R. patientia) and Polygonum bistorta, Polygonum hydropiper, Polygonum lapathifolium and Polygonum viviparum demonstrated the highest XO inhibitory activity (>85% inhibition) at 400 µg/mL. The IC50 values of the active extracts were also determined. On the basis of the results, these plants, and especially P. hydropiper and R. acetosella, are considered worthy of activity-guided phytochemical investigations.

  18. Design, Synthesis and Inhibitory Activity of Photoswitchable RET Kinase Inhibitors

    NASA Astrophysics Data System (ADS)

    Ferreira, Rubén; Nilsson, Jesper R.; Solano, Carlos; Andréasson, Joakim; Grøtli, Morten

    2015-05-01

    REarranged during Transfection (RET) is a transmembrane receptor tyrosine kinase required for normal development and maintenance of neurons of the central and peripheral nervous systems. Deregulation of RET and hyperactivity of the RET kinase is intimately connected to several types of human cancers, most notably thyroid cancers, making it an attractive therapeutic target for small-molecule kinase inhibitors. Novel approaches, allowing external control of the activity of RET, would be key additions to the signal transduction toolbox. In this work, photoswitchable RET kinase inhibitors based on azo-functionalized pyrazolopyrimidines were developed, enabling photonic control of RET activity. The most promising compound displays excellent switching properties and stability with good inhibitory effect towards RET in cell-free as well as live-cell assays and a significant difference in inhibitory activity between its two photoisomeric forms. As the first reported photoswitchable small-molecule kinase inhibitor, we consider the herein presented effector to be a significant step forward in the development of tools for kinase signal transduction studies with spatiotemporal control over inhibitor concentration in situ.

  19. Xanthine oxidase inhibitory activity of some Indian medical plants.

    PubMed

    Umamaheswari, Muthuswamy; AsokKumar, Kuppusamy; Somasundaram, Arumugam; Sivashanmugam, Thirumalaisamy; Subhadradevi, Varadharajan; Ravi, Thenvungal Kochupapy

    2007-02-12

    Xanthine oxidase inhibitory activity was assayed from six species belonging to different families traditionally used for the treatment of gout and related symptoms by indigenous people of India. The aqueous, methanol-water mixture and methanolic extract of these plants were used for the experiment. Of the 18 extracts assayed, 14 extracts demonstrated xanthine oxidase inhibitory activity at 100 microg/ml, among which 10 extracts showed an inhibition greater than 50% and IC(50) values below 100 microg/ml. The methanolic extracts of Coccinia grandis, Datura metel, Strychnos nux-vomica and Vitex negundo showed more than 50% inhibition, hence, they were screened for their in vivo hypouricaemic activity against potassium oxonate-induced hyperuricaemia in mice. Methanolic extracts of Coccinia grandis and Vitex negundo showed a significant decrease in the serum urate level (3.90+/-0.07 mg/dl, P<0.001) and (6.26+/-0.06 mg/dl, P<0.01), respectively, when compared to hyperuricaemic control (11.42+/-0.14 mg/dl). This effect is almost similar to the serum urate level of allopurinol (3.89+/-0.07 mg/dl).

  20. Design, Synthesis and Inhibitory Activity of Photoswitchable RET Kinase Inhibitors

    PubMed Central

    Ferreira, Rubén; Nilsson, Jesper R.; Solano, Carlos; Andréasson, Joakim; Grøtli, Morten

    2015-01-01

    REarranged during Transfection (RET) is a transmembrane receptor tyrosine kinase required for normal development and maintenance of neurons of the central and peripheral nervous systems. Deregulation of RET and hyperactivity of the RET kinase is intimately connected to several types of human cancers, most notably thyroid cancers, making it an attractive therapeutic target for small-molecule kinase inhibitors. Novel approaches, allowing external control of the activity of RET, would be key additions to the signal transduction toolbox. In this work, photoswitchable RET kinase inhibitors based on azo-functionalized pyrazolopyrimidines were developed, enabling photonic control of RET activity. The most promising compound displays excellent switching properties and stability with good inhibitory effect towards RET in cell-free as well as live-cell assays and a significant difference in inhibitory activity between its two photoisomeric forms. As the first reported photoswitchable small-molecule kinase inhibitor, we consider the herein presented effector to be a significant step forward in the development of tools for kinase signal transduction studies with spatiotemporal control over inhibitor concentration in situ. PMID:25944708

  1. Lanostanoids with acetylcholinesterase inhibitory activity from the mushroom Haddowia longipes.

    PubMed

    Zhang, Shuang-Shuang; Ma, Qing-Yun; Huang, Sheng-Zhuo; Dai, Hao-Fu; Guo, Zhi-Kai; Yu, Zhi-Fang; Zhao, You-Xing

    2015-02-01

    Nine lanostanoids, together with nine known ones, were isolated from the ethyl acetate extract of the fruiting bodies of the mushroom Haddowia longipes. Their structures were elucidated as 11-oxo-ganoderiol D, lanosta-8-en-7,11-dioxo-3β-acetyloxy-24,25,26-trihydroxy, lanosta-8-en-7-oxo-3β-acetyloxy-11β,24,25,26-tetrahydroxy, lanosta-7,9(11)-dien-3β-acetyloxy-24,25,26-trihydroxy, lanosta-7,9(11)-dien-3β-acetyloxy-24,26-dihydroxy-25-methoxy, 11-oxo-lucidadiol, 11β-hydroxy-lucidadiol, lucidone H and lanosta-7,9(11),24E-trien-3β-acetyloxy-26,27-dihydroxy by analysing their 1D/2D NMR and MS spectra. In addition, bioassays of inhibitory activity against acetylcholinesterase (AChE) of all compounds showed that thirteen compounds possessed inhibitory activity against AChE with the percentage inhibition ranging from 10.3% to 42.1% when tested at 100 μM.

  2. Origin of aromatase inhibitory activity via proteochemometric modeling.

    PubMed

    Simeon, Saw; Spjuth, Ola; Lapins, Maris; Nabu, Sunanta; Anuwongcharoen, Nuttapat; Prachayasittikul, Virapong; Wikberg, Jarl E S; Nantasenamat, Chanin

    2016-01-01

    Aromatase, the rate-limiting enzyme that catalyzes the conversion of androgen to estrogen, plays an essential role in the development of estrogen-dependent breast cancer. Side effects due to aromatase inhibitors (AIs) necessitate the pursuit of novel inhibitor candidates with high selectivity, lower toxicity and increased potency. Designing a novel therapeutic agent against aromatase could be achieved computationally by means of ligand-based and structure-based methods. For over a decade, we have utilized both approaches to design potential AIs for which quantitative structure-activity relationships and molecular docking were used to explore inhibitory mechanisms of AIs towards aromatase. However, such approaches do not consider the effects that aromatase variants have on different AIs. In this study, proteochemometrics modeling was applied to analyze the interaction space between AIs and aromatase variants as a function of their substructural and amino acid features. Good predictive performance was achieved, as rigorously verified by 10-fold cross-validation, external validation, leave-one-compound-out cross-validation, leave-one-protein-out cross-validation and Y-scrambling tests. The investigations presented herein provide important insights into the mechanisms of aromatase inhibitory activity that could aid in the design of novel potent AIs as breast cancer therapeutic agents. PMID:27190705

  3. Origin of aromatase inhibitory activity via proteochemometric modeling

    PubMed Central

    Simeon, Saw; Spjuth, Ola; Lapins, Maris; Nabu, Sunanta; Anuwongcharoen, Nuttapat; Prachayasittikul, Virapong; Wikberg, Jarl E.S.

    2016-01-01

    Aromatase, the rate-limiting enzyme that catalyzes the conversion of androgen to estrogen, plays an essential role in the development of estrogen-dependent breast cancer. Side effects due to aromatase inhibitors (AIs) necessitate the pursuit of novel inhibitor candidates with high selectivity, lower toxicity and increased potency. Designing a novel therapeutic agent against aromatase could be achieved computationally by means of ligand-based and structure-based methods. For over a decade, we have utilized both approaches to design potential AIs for which quantitative structure–activity relationships and molecular docking were used to explore inhibitory mechanisms of AIs towards aromatase. However, such approaches do not consider the effects that aromatase variants have on different AIs. In this study, proteochemometrics modeling was applied to analyze the interaction space between AIs and aromatase variants as a function of their substructural and amino acid features. Good predictive performance was achieved, as rigorously verified by 10-fold cross-validation, external validation, leave-one-compound-out cross-validation, leave-one-protein-out cross-validation and Y-scrambling tests. The investigations presented herein provide important insights into the mechanisms of aromatase inhibitory activity that could aid in the design of novel potent AIs as breast cancer therapeutic agents. PMID:27190705

  4. Origin of aromatase inhibitory activity via proteochemometric modeling.

    PubMed

    Simeon, Saw; Spjuth, Ola; Lapins, Maris; Nabu, Sunanta; Anuwongcharoen, Nuttapat; Prachayasittikul, Virapong; Wikberg, Jarl E S; Nantasenamat, Chanin

    2016-01-01

    Aromatase, the rate-limiting enzyme that catalyzes the conversion of androgen to estrogen, plays an essential role in the development of estrogen-dependent breast cancer. Side effects due to aromatase inhibitors (AIs) necessitate the pursuit of novel inhibitor candidates with high selectivity, lower toxicity and increased potency. Designing a novel therapeutic agent against aromatase could be achieved computationally by means of ligand-based and structure-based methods. For over a decade, we have utilized both approaches to design potential AIs for which quantitative structure-activity relationships and molecular docking were used to explore inhibitory mechanisms of AIs towards aromatase. However, such approaches do not consider the effects that aromatase variants have on different AIs. In this study, proteochemometrics modeling was applied to analyze the interaction space between AIs and aromatase variants as a function of their substructural and amino acid features. Good predictive performance was achieved, as rigorously verified by 10-fold cross-validation, external validation, leave-one-compound-out cross-validation, leave-one-protein-out cross-validation and Y-scrambling tests. The investigations presented herein provide important insights into the mechanisms of aromatase inhibitory activity that could aid in the design of novel potent AIs as breast cancer therapeutic agents.

  5. Xanthine oxidase inhibitory activity of Lychnophora species from Brazil ("Arnica").

    PubMed

    Filha, Z S Ferraz; Vitolo, I F; Fietto, L G; Lombardi, J A; Saúde-Guimarães, D A

    2006-08-11

    Twenty-two extracts from five Lychnophora species and one Lychnophoriopsis species, traditionally used in Brazil as analgesic, anti-inflammatory, and to treat bruise and rheumatism were examined for the inhibition of xanthine oxidase (XO), the enzyme that catalyses the metabolism of hypoxanthine and xanthine into uric acid. Sixteen extracts were tested. All of them were found to have excellent XO inhibitory activity, with inhibitions greater than 38% at 100 microg/mL in the assay mixture. The most active plants examined were Lychnophora trichocarpha, Lychnophora ericoides, Lychnophora staavioides and Lychnophoriopsis candelabrum, with inhibitions of 77%, 78%, 66% and 63% at 100 microg/mL, respectively, and IC(50) values of 6.16, 8.28, 33.97 and 37.70 microg/mL, respectively.

  6. Screening of selected Indian medicinal plants for acetylcholinesterase inhibitory activity.

    PubMed

    Vinutha, B; Prashanth, D; Salma, K; Sreeja, S L; Pratiti, D; Padmaja, R; Radhika, S; Amit, A; Venkateshwarlu, K; Deepak, M

    2007-01-19

    Seventy-six plant extracts including methanolic and successive water extracts from 37 Indian medicinal plants were investigated for acetylcholinesterase (AChE) inhibitory activity (in vitro). Results indicated that methanolic extracts to be more active than water extracts. The potent AChE inhibiting methanolic plant extracts included Withania somnifera (root), Semecarpus anacardium (stem bark), Embelia ribes (Root), Tinospora cordifolia (stem), Ficus religiosa (stem bark) and Nardostachys jatamansi (rhizome). The IC(50) values obtained for these extracts were 33.38, 16.74, 23.04, 38.36, 73.69 and 47.21mug/ml, respectively. These results partly substantiate the traditional use of these herbs for improvement of cognition. PMID:16950584

  7. Average activity of excitatory and inhibitory neural populations

    NASA Astrophysics Data System (ADS)

    Roulet, Javier; Mindlin, Gabriel B.

    2016-09-01

    We develop an extension of the Ott-Antonsen method [E. Ott and T. M. Antonsen, Chaos 18(3), 037113 (2008)] that allows obtaining the mean activity (spiking rate) of a population of excitable units. By means of the Ott-Antonsen method, equations for the dynamics of the order parameters of coupled excitatory and inhibitory populations of excitable units are obtained, and their mean activities are computed. Two different excitable systems are studied: Adler units and theta neurons. The resulting bifurcation diagrams are compared with those obtained from studying the phenomenological Wilson-Cowan model in some regions of the parameter space. Compatible behaviors, as well as higher dimensional chaotic solutions, are observed. We study numerical simulations to further validate the equations.

  8. Aldose reductase inhibitory activity of compounds from Zea mays L.

    PubMed

    Kim, Tae Hyeon; Kim, Jin Kyu; Kang, Young-Hee; Lee, Jae-Yong; Kang, Il Jun; Lim, Soon Sung

    2013-01-01

    Aldose reductase (AR) inhibitors have a considerable therapeutic potential against diabetes complications and do not increase the risk of hypoglycemia. Through bioassay-guided fractionation of an EtOH extract of the kernel from purple corn (Zea mays L.), 7 nonanthocyanin phenolic compounds (compound 1-7) and 5 anthocyanins (compound 8-12) were isolated. These compounds were investigated by rat lens aldose reductase (RLAR) inhibitory assays. Kinetic analyses of recombinant human aldose reductase (rhAR) were performed, and intracellular galactitol levels were measured. Hirsutrin, one of 12 isolated compounds, showed the most potent RLAR inhibitory activity (IC(50), 4.78 μ M). In the kinetic analyses using Lineweaver-Burk plots of 1/velocity and 1/substrate concentration, hirsutrin showed competitive inhibition against rhAR. Furthermore, hirsutrin inhibited galactitol formation in rat lens and erythrocytes sample incubated with a high concentration of galactose; this finding indicates that hirsutrin may effectively prevent osmotic stress in hyperglycemia. Therefore, hirsutrin derived from Zea mays L. may be a potential therapeutic agent against diabetes complications. PMID:23586057

  9. Predicting Monoamine Oxidase Inhibitory Activity through Ligand-Based Models

    PubMed Central

    Vilar, Santiago; Ferino, Giulio; Quezada, Elias; Santana, Lourdes; Friedman, Carol

    2013-01-01

    The evolution of bio- and cheminformatics associated with the development of specialized software and increasing computer power has produced a great interest in theoretical in silico methods applied in drug rational design. These techniques apply the concept that “similar molecules have similar biological properties” that has been exploited in Medicinal Chemistry for years to design new molecules with desirable pharmacological profiles. Ligand-based methods are not dependent on receptor structural data and take into account two and three-dimensional molecular properties to assess similarity of new compounds in regards to the set of molecules with the biological property under study. Depending on the complexity of the calculation, there are different types of ligand-based methods, such as QSAR (Quantitative Structure-Activity Relationship) with 2D and 3D descriptors, CoMFA (Comparative Molecular Field Analysis) or pharmacophoric approaches. This work provides a description of a series of ligand-based models applied in the prediction of the inhibitory activity of monoamine oxidase (MAO) enzymes. The controlled regulation of the enzymes’ function through the use of MAO inhibitors is used as a treatment in many psychiatric and neurological disorders, such as depression, anxiety, Alzheimer’s and Parkinson’s disease. For this reason, multiple scaffolds, such as substituted coumarins, indolylmethylamine or pyridazine derivatives were synthesized and assayed toward MAO-A and MAO-B inhibition. Our intention is to focus on the description of ligand-based models to provide new insights in the relationship between the MAO inhibitory activity and the molecular structure of the different inhibitors, and further study enzyme selectivity and possible mechanisms of action. PMID:23231398

  10. Native New Zealand plants with inhibitory activity towards Mycobacterium tuberculosis

    PubMed Central

    2010-01-01

    Background Plants have long been investigated as a source of antibiotics and other bioactives for the treatment of human disease. New Zealand contains a diverse and unique flora, however, few of its endemic plants have been used to treat tuberculosis. One plant, Laurelia novae-zelandiae, was reportedly used by indigenous Maori for the treatment of tubercular lesions. Methods Laurelia novae-zelandiae and 44 other native plants were tested for direct anti-bacterial activity. Plants were extracted with different solvents and extracts screened for inhibition of the surrogate species, Mycobacterium smegmatis. Active plant samples were then tested for bacteriostatic activity towards M. tuberculosis and other clinically-important species. Results Extracts of six native plants were active against M. smegmatis. Many of these were also inhibitory towards M. tuberculosis including Laurelia novae-zelandiae (Pukatea). M. excelsa (Pohutukawa) was the only plant extract tested that was active against Staphylococcus aureus. Conclusions Our data provide support for the traditional use of Pukatea in treating tuberculosis. In addition, our analyses indicate that other native plant species possess antibiotic activity. PMID:20537175

  11. Inhibitory neurotransmission regulates vagal efferent activity and gastric motility.

    PubMed

    McMenamin, Caitlin A; Travagli, R Alberto; Browning, Kirsteen N

    2016-06-01

    The gastrointestinal tract receives extrinsic innervation from both the sympathetic and parasympathetic nervous systems, which regulate and modulate the function of the intrinsic (enteric) nervous system. The stomach and upper gastrointestinal tract in particular are heavily influenced by the parasympathetic nervous system, supplied by the vagus nerve, and disruption of vagal sensory or motor functions results in disorganized motility patterns, disrupted receptive relaxation and accommodation, and delayed gastric emptying, amongst others. Studies from several laboratories have shown that the activity of vagal efferent motoneurons innervating the upper GI tract is inhibited tonically by GABAergic synaptic inputs from the adjacent nucleus tractus solitarius. Disruption of this influential central GABA input impacts vagal efferent output, hence gastric functions, significantly. The purpose of this review is to describe the development, physiology, and pathophysiology of this functionally dominant inhibitory synapse and its role in regulating vagally determined gastric functions. PMID:27302177

  12. Bacterial maximum non-inhibitory and minimum inhibitory concentrations of different water activity depressing solutes.

    PubMed

    Cebrián, G; Arroyo, C; Mañas, P; Condón, S

    2014-10-01

    The NaCl MNICs (maximum non-inhibitory concentrations) and MICs (minimum inhibitory concentrations) for growth of various strains of six bacterial species were determined and then compared with those obtained for seven other solutes. The influence of prior growth conditions on the MNICs and MICs was also evaluated. No significant changes on the MNICs and MICs were found among the strains studied within each species. Among all factors investigated, only growth phase -for Gram-negatives- and growth at high NaCl concentrations led to a change in the NaCl MNICs. Species could be classified depending on its NaCl MNICs and MICs (in decreasing order) as follows: Staphylococcus aureus, Listeria monocytogenes, Cronobacter sakazakii, Enterococcus faecium, Escherichia coli and Salmonella Typhimurium. Similar results were obtained for KCl, LiCl, and sodium acetate, but not for the remaining solutes investigated (sucrose, glycerol, MgCl2 and CaCl2). Results obtained indicate that, in general, Gram-negatives showed lower MNICs and MICs than Gram-positives for all the solutes, S. aureus being the most solute tolerant microorganism. When compared on a molar basis, glycerol showed the highest MNICs and MICs for all the microorganisms -except for S. aureus- and LiCl the lowest ones. NaCl MNICs and MICs were not significantly different from those of KCl when compared on a molar basis. Therefore, the inhibitory action of NaCl could not be linked to the specific action of Na(+). Results also showed that the Na(+) tolerance of some species was Cl(-) dependent whereas for others it was not, and that factors others than aw-decrease contribute to the inhibitory action of LiCl, CaCl2 and MgCl2.

  13. Inhibitory effects of ionic liquids on the lactic dehydrogenase activity.

    PubMed

    Dong, Xing; Fan, Yunchang; Zhang, Heng; Zhong, Yingying; Yang, Yang; Miao, Juan; Hua, Shaofeng

    2016-05-01

    Ionic liquids (ILs) were widely used in scientific and industrial application and have been reported to possess potential toxicity to the environment and human health. The effects of six typical N-methylimidazolium-based ILs ([Cnmim]X, n=4, 6, 8; X=Br(-), Cl(-), BF4(-), CF3SO3(-)) on the lactic dehydrogenase (LDH) activity and the molecular interaction mechanism of ILs and the LDH were investigated with the aid of spectroscopic techniques. Experimental results showed that the LDH activity was inhibited in the presence of ILs. For the ILs with the same anion but different cations, their inhibitory ability on the LDH activity increased with increasing the alkyl chain length on the IL cation. Thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS) were obtained by analyzing the fluorescence behavior of LDH with the addition of ILs. Both positive ΔH and ΔS suggested that hydrophobicity was the major driven force in the interaction process as expected. PMID:26802246

  14. Inhibitory Effects of Angelica Polysaccharide on Activation of Mast Cells

    PubMed Central

    Mao, Wei-An; Sun, Yuan-Yuan; Mao, Jing-Yi; Wang, Li; Zhang, Jian; Zhou, Jie; Rahman, Khalid; Ye, Ying

    2016-01-01

    This study was designed to investigate the inhibitory effects of Angelica polysaccharide (AP) on activation of mast cells and its possible molecular mechanism. In our study, we determined the proinflammatory cytokines and allergic mediators in anti-DNP IgE stimulated RBL-2H3 cells and found that AP (50, 100, and 200 μg/mL) significantly decreased the release of histamine, β-hexosaminidase, leukotrienes C4 (LTC4), IL-1, IL-4, TNF-α, IL-6, and human monocyte chemotactic protein-1 (MCP-1/CCL2) (p < 0.05). In addition, Ca2+ entry was inhibited by treatment with AP. AP also downregulated the protein expressions of p-Fyn, p-Akt, p-P38, IL-4, TNF-α, and NF-κB p65 in both Fyn gene upregulated and normal RBL-2H3 cells (p < 0.05). Collectively, our results showed that AP could inhibit the activation of mast cells via suppressing the releases of proinflammatory cytokines allergic mediators, Gab2/PI3-K/Akt and Fyn/Syk pathways. PMID:27200102

  15. Inhibitory activity of spices and essential oils on psychrotrophic bacteria.

    PubMed

    Fabio, A; Corona, A; Forte, E; Quaglio, P

    2003-01-01

    This study was designed to evaluate "in vitro" the inhibitory effects of spices and essential oils on the growth of psycrotrophic food-borne bacteria: Aeromonas hydrophila, Listeria monocytogenes and Yersinia enterocolitica. The sensitivity to nine spices and their oils (chilli, cinnamon, cloves, ginger, nutmeg, oregano, rosemary, sage, thyme) was studied. Antibacterial activity was evaluated on liquid and solid medium. Spices: 1% concentration of each spice was added separately to Triptic Soy Broth and then inoculated to contain 10(8)/ml organism and held to 4 degrees C for 7 days. Populations of test organism were determined on Triptic Soy Agar. Oils: Inhibition of growth was tested by using the paper disc agar diffusion method (at 35, 20 and 4 degrees C) and measuring their inhibition zone. MIC was determined by the broth microdilution method. Some culinary spices produce antibacterial activity: inhibition of growth ranged from complete (cinnamon and cloves against A. hydrophila) to no inhibition. Antibacterial inhibition zone ranged from 8 mm to 45 mm: thyme essential oil showed the greatest inhibition against A. hydrophila. PMID:12578319

  16. Toward the Prediction of FBPase Inhibitory Activity Using Chemoinformatic Methods

    PubMed Central

    Hao, Ming; Zhang, Shuwei; Qiu, Jieshan

    2012-01-01

    Currently, Chemoinformatic methods are used to perform the prediction for FBPase inhibitory activity. A genetic algorithm-random forest coupled method (GA-RF) was proposed to predict fructose 1,6-bisphosphatase (FBPase) inhibitors to treat type 2 diabetes mellitus using the Mold2 molecular descriptors. A data set of 126 oxazole and thiazole analogs was used to derive the GA-RF model, yielding the significant non-cross-validated correlation coefficient r2ncv and cross-validated r2cv values of 0.96 and 0.67 for the training set, respectively. The statistically significant model was validated by a test set of 64 compounds, producing the prediction correlation coefficient r2pred of 0.90. More importantly, the building GA-RF model also passed through various criteria suggested by Tropsha and Roy with r2o and r2m values of 0.90 and 0.83, respectively. In order to compare with the GA-RF model, a pure RF model developed based on the full descriptors was performed as well for the same data set. The resulting GA-RF model with significantly internal and external prediction capacities is beneficial to the prediction of potential oxazole and thiazole series of FBPase inhibitors prior to chemical synthesis in drug discovery programs. PMID:22837677

  17. Antioxidant Activity and α-Glucosidase Inhibitory Activities of the Polycondensate of Catechin with Glyoxylic Acid

    PubMed Central

    Ma, Hanjun; Liu, Benguo

    2016-01-01

    In order to investigate polymeric flavonoids, the polycondensate of catechin with glyoxylic acid (PCG) was prepared and its chemically antioxidant, cellular antioxidant (CAA) and α-glucosidase inhibitory activities were evaluated. The DPPH and ABTS radical scavenging activities and antiproliferative effect of PCG were lower than those of catechin, while PCG had higher CAA activity than catechin. In addition, PCG had very high α-glucosidase inhibitory activities (IC50 value, 2.59 μg/mL) in comparison to catechin (IC50 value, 239.27 μg/mL). Inhibition kinetics suggested that both PCG and catechin demonstrated a mixture of noncompetitive and anticompetitive inhibition. The enhanced CAA and α-glucosidase inhibitor activities of PCG could be due to catechin polymerization enhancing the binding capacity to the cellular membrane and enzymes. PMID:26960205

  18. Differential activity-dependent, homeostatic plasticity of two neocortical inhibitory circuits.

    PubMed

    Bartley, Aundrea F; Huang, Z Josh; Huber, Kimberly M; Gibson, Jay R

    2008-10-01

    Chronic changes in neuronal activity homeostatically regulate excitatory circuitry. However, little is known about how activity regulates inhibitory circuits or specific inhibitory neuron types. Here, we examined the activity-dependent regulation of two neocortical inhibitory circuits--parvalbumin-positive (Parv+) and somatostatin-positive (Som+)--using paired recordings of synaptically coupled neurons. Action potentials were blocked for 5 days in slice culture, and unitary synaptic connections among inhibitory/excitatory neuron pairs were examined. Chronic activity blockade caused similar and distinct changes between the two inhibitory circuits. First, increases in intrinsic membrane excitability and excitatory synaptic drive in both inhibitory subtypes were consistent with the homeostatic regulation of firing rate of these neurons. On the other hand, inhibitory synapses originating from these two subtypes were differentially regulated by activity blockade. Parv+ unitary inhibitory postsynaptic current (uIPSC) strength was decreased while Som+ uIPSC strength was unchanged. Using short-duration stimulus trains, short-term plasticity for both unitary excitatory postsynaptic current (uEPSCs) and uIPSCs was unchanged in Parv+ circuitry while distinctively altered in Som+ circuitry--uEPSCs became less facilitating and uIPSCs became more depressing. In the context of recurrent inhibition, these changes would result in a frequency-dependent shift in the relative influence of each circuit. The functional changes at both types of inhibitory connections appear to be mediated by increases in presynaptic release probability and decreases in synapse number. Interestingly, these opposing changes result in decreased Parv+-mediated uIPSCs but balance out to maintain normal Som+-mediated uIPSCs. In summary, these results reveal that inhibitory circuitry is not uniformly regulated by activity levels and may provide insight into the mechanisms of both normal and pathological

  19. Inhibitory effect of curcuminoids and tetrahydrocurcuminoids on equine activated neutrophils and myeloperoxidase activity.

    PubMed

    Franck, T; Kohnen, S; Grulke, S; Neven, P; Goutman, Y; Peters, F; Pirotte, B; Deby-Dupont, G; Serteyn, D

    2008-01-01

    In the horse, the inflammation response to various pathologies (intestinal strangulations, laminitis, etc.) involves an excessive stimulation of the polymorphonuclear neutrophils releasing reactive oxygen species (ROS) and myeloperoxidase (MPO). The aim of the present work was to study the effect of natural polyphenols, curcuminoids and tetrahydrocurcuminoids (THC) on isolated stimulated equine neutrophils and on the activity of purified MPO. The ROS production and the release of MPO by activated neutrophils were measured by chemiluminescence and ELISA techniques, respectively. The activity of purified MPO was measured by studying its nitration, chlorination or oxidation capacity and by using an original method called SIEFED allowing the study of drug interaction with the enzyme without interferences of the medium. Curcuminoids and THC had dose-dependent inhibitory effects on ROS production and MPO release by activated neutrophils and on purified MPO activity. We suggest that the higher efficacy of curcuminoids versus THC could be explained, at least partially, by its chemical structure: the conjugated double bounds and the plane structure of curcuminoids made easier the neutralization of the radical species generated by activated neutrophils and the interaction of the drug with the active site of MPO. These inhibitory effects of curcuminoids on the oxidant activity of equine neutrophils and on MPO activity open therapeutic perspectives in equine pathologies with excessive inflammatory reactions.

  20. Synthesis of sulfanilamide derivatives and investigation of in vitro inhibitory activities and antimicrobial and physical properties.

    PubMed

    Turkmen, Hasan; Zengin, Gulay; Buyukkircali, Belkis

    2011-06-01

    Novel sulfanilamide derivatives were synthesized and evaluated for carbonic anhydrase inhibitory activity as a target for the treatment of glaucoma, and antibacterial properties for use in chemotherapy. Synthesized compounds were characterized by FT-IR, (1)H NMR, (13)C NMR and photoluminescence. In vitro inhibitory activities were measured by UV-Vis and some of the compounds were found have greater inhibitory effects than the lead compound sulfanilamide. The correlation between inhibitory activity, biological properties and the physicochemical properties of water solubility and partition coefficients was also investigated. Sulfanilamide derivatives gave intense emissions upon irradiation by UV light and a dimethyl substituted compound and a cyclic analog have photoluminescence quantum yields 42% and 31% and long excited-state lifetimes of 3.92 and 2.91 ns, respectively. PMID:21429552

  1. Inhibitory effect of hemin on the mutagenic activities of carcinogens.

    PubMed

    Arimoto, S; Negishi, T; Hayatsu, H

    1980-11-01

    An inhibitory effect of hemin on mutagenicities of a range of carcinogens was found by adding hemin to the preincubation mixture of the Ames' test. Strong inhibitions were observed for benzo[alpha]pyrene, 3-methylcholanthrene, 7,10-dimethylbenz[alpha]anthracene, chrysene, 2-acetylaminofluorene, 2-nitrofluorene and aflatoxin B1. Generally, 50% inhibition was caused by an amount of hemin 1--2 equivalents to the mutagen. Excess of hemin caused complete inhibitions. Hemin did not affect the mutagenicities of 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide, 4-nitroquinoline-1-oxide, nitromin, N-methyl-N-nitrosourea, N-methyl-N'-nitro-N-nitrosoguanidine, N-nitrosodi-n-butyl-amine, quinoxaline-1,4-dioxide and carbadox. Biliverdin, bilirubin and chlorophyllin were also effective as inhibitors for the mutagenicity of benzo[alpha]pyrene. PMID:7226136

  2. ACR-12 ionotropic acetylcholine receptor complexes regulate inhibitory motor neuron activity in Caenorhabditis elegans.

    PubMed

    Petrash, Hilary A; Philbrook, Alison; Haburcak, Marian; Barbagallo, Belinda; Francis, Michael M

    2013-03-27

    Heterogeneity in the composition of neurotransmitter receptors is thought to provide functional diversity that may be important in patterning neural activity and shaping behavior (Dani and Bertrand, 2007; Sassoè-Pognetto, 2011). However, this idea has remained difficult to evaluate directly because of the complexity of neuronal connectivity patterns and uncertainty about the molecular composition of specific receptor types in vivo. Here we dissect how molecular diversity across receptor types contributes to the coordinated activity of excitatory and inhibitory motor neurons in the nematode Caenorhabditis elegans. We show that excitatory and inhibitory motor neurons express distinct populations of ionotropic acetylcholine receptors (iAChRs) requiring the ACR-12 subunit. The activity level of excitatory motor neurons is influenced through activation of nonsynaptic iAChRs (Jospin et al., 2009; Barbagallo et al., 2010). In contrast, synaptic coupling of excitatory and inhibitory motor neurons is achieved through a second population of iAChRs specifically localized at postsynaptic sites on inhibitory motor neurons. Loss of ACR-12 iAChRs from inhibitory motor neurons leads to reduced synaptic drive, decreased inhibitory neuromuscular signaling, and variability in the sinusoidal motor pattern. Our results provide new insights into mechanisms that establish appropriately balanced excitation and inhibition in the generation of a rhythmic motor behavior and reveal functionally diverse roles for iAChR-mediated signaling in this process. PMID:23536067

  3. Synaptic basis for intense thalamocortical activation of feedforward inhibitory cells in neocortex.

    PubMed

    Cruikshank, Scott J; Lewis, Timothy J; Connors, Barry W

    2007-04-01

    The thalamus provides fundamental input to the neocortex. This input activates inhibitory interneurons more strongly than excitatory neurons, triggering powerful feedforward inhibition. We studied the mechanisms of this selective neuronal activation using a mouse somatosensory thalamocortical preparation. Notably, the greater responsiveness of inhibitory interneurons was not caused by their distinctive intrinsic properties but was instead produced by synaptic mechanisms. Axons from the thalamus made stronger and more frequent excitatory connections onto inhibitory interneurons than onto excitatory cells. Furthermore, circuit dynamics allowed feedforward inhibition to suppress responses in excitatory cells more effectively than in interneurons. Thalamocortical excitatory currents rose quickly in interneurons, allowing them to fire action potentials before significant feedforward inhibition emerged. In contrast, thalamocortical excitatory currents rose slowly in excitatory cells, overlapping with feedforward inhibitory currents that suppress action potentials. These results demonstrate the importance of selective synaptic targeting and precise timing in the initial stages of neocortical processing.

  4. Synthesis and acetylcholinesterase inhibitory activity of polyhydroxylated sulfated steroids: structure/activity studies.

    PubMed

    Richmond, Victoria; Murray, Ana P; Maier, Marta S

    2013-11-01

    Disulfated and trisulfated steroids have been synthesized from cholesterol and their acetylcholinesterase inhibitory activity has been evaluated. In our studies we have found that the activity was not only dependent on the location of the sulfate groups but on their configurations. 2β,3α,6α-trihydroxy-5α-cholestan-6-one trisulfate (18) was the most active steroid with an IC50 value of 15.48 μM comparable to that of 2β,3α-dihydroxy-5α-cholestan-6-one disulfate (1). Both compounds were found to be less active than the reference compound eserine. The butyrylcholinesterase activity of 1 and 18 was one magnitude lower than that against acetylcholinesterase revealing a selective inhibitor profile.

  5. 5-Alpha reductase inhibitor use and prostate cancer survival in the Finnish Prostate Cancer Screening Trial.

    PubMed

    Murtola, Teemu J; Karppa, Elina K; Taari, Kimmo; Talala, Kirsi; Tammela, Teuvo L J; Auvinen, Anssi

    2016-06-15

    Randomized clinical trials have shown that use of 5α-reductase inhibitors (5-ARIs) lowers overall prostate cancer (PCa) risk compared to placebo, while the proportion of Gleason 8-10 tumors is elevated. It is unknown whether this affects PCa-specific survival. We studied disease-specific survival by 5-ARI usage in a cohort of 6,537 prostate cancer cases diagnosed in the Finnish Prostate Cancer Screening Trial and linked to the national prescription database for information on medication use. Cox proportional hazards regression was used to estimate hazard ratios and 95% confidence intervals for prostate cancer-specific deaths. For comparison, survival among alpha-blocker users was also evaluated. During the median follow-up of 7.5 years after diagnosis a total of 2,478 men died; 617 due to prostate cancer and 1,861 due to other causes. The risk of prostate cancer death did not differ between 5-ARI users and nonusers (multivariable adjusted HR 0.94, 95% CI 0.72-1.24 and HR 0.98, 95% CI 0.69-1.41 for usage before and after the diagnosis, respectively). Alpha-blocker usage both before and after diagnosis was associated with increased risk of prostate cancer death (HR 1.29, 95% CI 1.08-1.54 and HR 1.56, 95% CI 1.30-1.86, respectively). The risk increase vanished in long-term alpha-blocker usage. Use of 5-ARIs does not appear to affect prostate cancer mortality when used in management of benign prostatic hyperplasia. Increased risk associated with alpha-blocker usage should prompt further exploration on the prognostic role of lower urinary tract symptoms.

  6. Screening for antimalarial and acetylcholinesterase inhibitory activities of some Iranian seaweeds.

    PubMed

    Ghannadi, A; Plubrukarn, A; Zandi, K; Sartavi, K; Yegdaneh, A

    2013-04-01

    Alcoholic extracts of 8 different types of seaweeds from Iran's Persian Gulf were tested for their antimalarial and acetylcholinesterase enzyme (AChE) inhibitory activities for the first time. A modified Ellman and Ingkaninan method was used for measuring AChE inhibitory activity in which galanthamine was used as the reference. The antimalarial assay was performed using microculture radioisotope technique. Mefloquine and dihydroartemisinin were uased as the standards. The extract of Sargassum boveanum (Sargasseae family) showed the highest AChE inhibitory activity (IC50 equals to 1 mg ml(-1)) while Cystoseira indica (Cystoseiraceae family) exhibited the least activity (IC50 of 11 mg ml(-1)). The species from Rhodophyta (Gracilaria corticata and Gracilaria salicornia) also showed moderate activities (IC509.5, 8.7 mg ml(-1), respectively). All extracts were inactive in antimalarial assay. PMID:24019820

  7. Structural requirement of isoflavonones for the inhibitory activity of interleukin-5.

    PubMed

    Jung, Sang-Hun; Cho, Soo-Hyun; Dang, The Hung; Lee, Jee-Hyun; Ju, Jung-Hun; Kim, Mi-Kyung; Lee, Seung-Ho; Ryu, Jae-Chun; Kim, Youngsoo

    2003-05-01

    Sophoricoside isolated from Sophora japonica is a glycoside of isoflavonone as an inhibitor of interleukin (IL)-5. To identify structural requirements of this isoflavonone for its inhibitory activity against IL-5, isoflavonones, isoflavanones, and their glycosides were prepared and their inhibitory activity was tested against IL-5. Among them, 5-benzyloxy-3-(4-hydroxyphenyl)chromen-4-one (4b, 87.9% inhibition at 50 microM, IC(50)=15.3 microM) shows the most potent activity, comparable with that of sophoricoside. The important structural requirements of these isoflavonone analogs exhibiting the inhibitory activity against IL-5 were recognized as (1) planarity of chromen-4-one ring, (2) existence of phenolic hydroxyl at 4-position of B ring, and (3) introduction of benzyloxy at 5-position, which may act as a bulky group for occupying hydrophobic pocket in putative binding site. However the glucopyranosyl moiety of sophoricoside is not an essential motif for the activity. PMID:12767605

  8. Inhibitory activity of isoniazid and ethionamide against Cryptococcus biofilms.

    PubMed

    Cordeiro, Rossana de Aguiar; Serpa, Rosana; Marques, Francisca Jakelyne de Farias; de Melo, Charlline Vládia Silva; Evangelista, Antonio José de Jesus; Mota, Valquíria Ferreira; Brilhante, Raimunda Sâmia Nogueira; Bandeira, Tereza de Jesus Pinheiro Gomes; Rocha, Marcos Fábio Gadelha; Sidrim, José Júlio Costa

    2015-11-01

    In recent years, the search for drugs to treat systemic and opportunistic mycoses has attracted great interest from the scientific community. This study evaluated the in vitro inhibitory effect of the antituberculosis drugs isoniazid and ethionamide alone and combined with itraconazole and fluconazole against biofilms of Cryptococcus neoformans and Cryptococcus gattii. Antimicrobials were tested at defined concentrations after susceptibility assays with Cryptococcus planktonic cells. In addition, we investigated the synergistic interaction of antituberculosis drugs and azole derivatives against Cryptococcus planktonic cells, as well as the influence of isoniazid and ethionamide on ergosterol content and cell membrane permeability. Isoniazid and ethionamide inhibited both biofilm formation and viability of mature biofilms. Combinations formed by antituberculosis drugs and azoles proved synergic against both planktonic and sessile cells, showing an ability to reduce Cryptococcus biofilms by approximately 50%. Furthermore, isoniazid and ethionamide reduced the content of ergosterol in Cryptococcus spp. planktonic cells and destabilized or permeabilized the fungal cell membrane, leading to leakage of macromolecules. Owing to the paucity of drugs able to inhibit Cryptococcus biofilms, we believe that the results presented here might be of interest in the designing of new antifungal compounds.

  9. Honey, pollen, and propolis extracts show potent inhibitory activity against the zinc metalloenzyme carbonic anhydrase.

    PubMed

    Sahin, H; Aliyazicioglu, R; Yildiz, O; Kolayli, S; Innocenti, A; Supuran, C T

    2011-06-01

    Three different honey extracts from the endemic plant in the Black Sea region Rhododendron ponticum, were investigated for their inhibitory effects against the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1), more precisely the human (h) isoforms hCA I and hCA II. Hexane, methanol, ethanol, and water solid-phase extractions (SPEs) showed inhibitory activity towards the two CA isozymes which were related to the total phenolic content. The highest inhibitory effects (0.036-0.039 mg/mL) were those of propolis methanolic extract. Among the three different samples investigated here, the aqueous extracts showed lower inhibitory effects compared to the organic solvent SPE extracts (in the range of 1.150- 5.144 mg/mL). The studied honey extracts constitute an interesting source of phenolic derivatives that might serve to identify lead compounds, targeting the physiologically relevant enzymes CA I and CA II.

  10. Inhibitory activities of 2-pyridinecarboxylic acid analogs on phytogrowth and enzymes.

    PubMed

    Sakagami, Y; Tsujibo, H; Hirai, Y; Yamada, T; Numata, A; Inamori, Y

    1999-11-01

    Five 2-pyridinecarboxylic acid-related compounds (1, 2 and 5-7) showed germination inhibition against the seed of Brassica campestris L. subsp. rapa HOOK fil et ANDERS at a concentration of 5.0 x 10(-4) M. These compounds also demonstrated inhibitory activity on the growth of the root of this plant at a concentration of 3.0 x 10(-4) M; among these compounds, 2-pyridylacetic acid (5) showed the strongest inhibitory activity, and the effect was slightly stronger than that of sodium 2,4-dichlorophenoxyacetate (2,4-D) used as a positive control. The amounts of chlorophyll in the cotyledons of this plant treated with these active compounds was lower than that of the control group. Four compounds (1 and 5-7) with germination inhibition also showed inhibitory activities against alpha-amylase and carboxypeptidase A, and 5 was the strongest inhibitor toward both enzymes.

  11. [Activation and inhibitory types of brain neuronal sinchronisation: genesis and functional significance].

    PubMed

    Shul'gina, G I

    2007-01-01

    The generalization of studies of the systemic work of cortical neurons during the information processing initiated in Livanov's laboratory allows us to make the following conclusions in terms of the modem state of the problem. In different brain structures, there is a considerable degree of correlation between neuronal activities and slow potential oscillations. In the state of rest or deep extinction, the synchronization of brain neurons increases by the inhibitory type. In the active state of the brain, the degree of neuronal synchronization increases by the activation type. Both processes are determined by the involvement of the whole brain inhibitory or activation systems, respectively. A relative augmentation of inhibitory processes results in a restriction of information transmission in the cortex and prevents its fixation in memory of the system. A decrease in inhibition facilitates the excitation thransmission in the interconnected brain structures. Synchronous convergence of ordered polse flows ensures the information fixation during learning.

  12. Glucosidase inhibitory activity and antioxidant activity of flavonoid compound and triterpenoid compound from Agrimonia Pilosa Ledeb

    PubMed Central

    2014-01-01

    Background In Chinese traditional medicine, Agrimonia pilosa Ledeb (APL) exhibits great effect on treatment of type 2 diabetes mellitus (T2DM), however its mechanism is still unknown. Considering that T2DM are correlated with postprandial hyperglycemia and oxidative stress, we investigated the α-glucosidase inhibitory activity and the antioxidant activity of flavonoid compound (FC) and triterpenoid compound (TC) from APL. Methods Entire plants of APL were extracted using 95% ethanol and 50% ethanol successively. The resulting extracts were partitioned and isolated by applying liquid chromatography using silica gel column and Sephadex LH 20 column to give FC and TC. The content of total flavonoids in FC and the content of total triterpenoids in TC were determined by using UV spectrophotometry. HPLC analysis was used to identify and quantify the monomeric compound in FC and TC. The α-glucosidase inhibitory activities were determined using the chromogenic method with p-nitrophenyl-α-D-glucopyranoside as substrate. Antioxidant activities were assessed through three kinds of radical scavenging assays (DPPH radical, ABTS radical and hydroxyl radical) & β-carotene-linoleic acid assay. Results The results indicate FC is abundant of quercitrin, and hyperoside, and TC is abundant of 1β, 2β, 3β, 19α-tetrahydroxy-12-en-28-oic acid (265.2 mg/g) and corosolic acid (100.9 mg/g). The FC & the TC have strong α-glucosidase inhibitory activities with IC50 of 8.72 μg/mL and 3.67 μg/mL, respectively. We find that FC show competitive inhibition against α-glucosidase, while the TC exhibits noncompetitive inhibition. Furthermore, The FC exhibits significant radical scavenging activity with the EC50 values of 7.73 μg/mL, 3.64 μg/mL and 5.90 μg/mL on DPPH radical, hydroxyl radical and ABTS radical, respectively. The FC also shows moderate anti-lipid peroxidation activity with the IC50 values of 41.77 μg/mL on inhibiting β-carotene bleaching. Conclusion These results

  13. Inhibitory Activity of (+)-Usnic Acid against Non-Small Cell Lung Cancer Cell Motility

    PubMed Central

    Yang, Yi; Nguyen, Thanh Thi; Jeong, Min-Hye; Crişan, Florin; Yu, Young Hyun; Ha, Hyung-Ho; Choi, Kyung Hee; Jeong, Hye Gwang; Jeong, Tae Cheon; Lee, Kwang Youl; Kim, Kyung Keun; Hur, Jae-Seoun; Kim, Hangun

    2016-01-01

    Lichens are symbiotic organisms that produce various unique chemicals that can be used for pharmaceutical purposes. With the aim of screening new anti-cancer agents that inhibit cancer cell motility, we tested the inhibitory activity of seven lichen species collected from the Romanian Carpathian Mountains against migration and invasion of human lung cancer cells and further investigated the molecular mechanisms underlying their anti-metastatic activity. Among them, Alectoria samentosa, Flavocetraria nivalis, Alectoria ochroleuca, and Usnea florida showed significant inhibitory activity against motility of human lung cancer cells. HPLC results showed that usnic acid is the main compound in these lichens, and (+)-usnic acid showed similar inhibitory activity that crude extract have. Mechanistically, β-catenin-mediated TOPFLASH activity and KITENIN-mediated AP-1 activity were decreased by (+)-usnic acid treatment in a dose-dependent manner. The quantitative real-time PCR data showed that (+)-usnic acid decreased the mRNA level of CD44, Cyclin D1 and c-myc, which are the downstream target genes of both β-catenin/LEF and c-jun/AP-1. Also, Rac1 and RhoA activities were decreased by treatment with (+)-usnic acid. Interestingly, higher inhibitory activity for cell invasion was observed when cells were treated with (+)-usnic acid and cetuximab. These results implied that (+)-usnic acid might have potential activity in inhibition of cancer cell metastasis, and (+)-usnic acid could be used for anti-cancer therapy with a distinct mechanisms of action. PMID:26751081

  14. Cyclolinopeptides, cyclic peptides from flaxseed with osteoclast differentiation inhibitory activity.

    PubMed

    Kaneda, Toshio; Yoshida, Haruka; Nakajima, Yuki; Toishi, Minako; Nugroho, Alfarius Eko; Morita, Hiroshi

    2016-04-01

    Flaxseed (Linum usitatissimum seed) is widely used in food and natural health products. In our search for osteoclast differentiation inhibitors, some cyclic peptides isolated from flaxseed, known as the cyclolinopeptides, were discovered to have osteoclast differentiation inhibition activity. The osteoclast differentiation inhibition activity of cyclolinopeptides A-I (1-9) and their related derivatives (10-14) are described herein. Cyclolinopeptides F, H and I (6, 8 and 9), in particular, showed potent osteoclast differentiation inhibition activity. PMID:26923696

  15. Effect of reactive site loop elongation on the inhibitory activity of C1-inhibitor.

    PubMed

    Bos, Ineke G A; Lubbers, Yvonne T P; Eldering, Eric; Abrahams, Jan Pieter; Hack, C Erik

    2004-06-01

    The serine protease inhibitor C1-Inhibitor (C1-Inh) inhibits several complement- and contact-system proteases, which play an important role in inflammation. C1-Inh has a short reactive site loop (RSL) compared to other serpins. RSL length determines the inhibitory activity of serpins. We investigated the effect of RSL elongation on inhibitory activity of C1-Inh by insertion of one or two alanine residues in the RSL. One of five mutants had an increased association rate with kallikrein, but was nevertheless a poor inhibitor because of a simultaneous high stoichiometry of inhibition (>10). The association rate of the other variants was lower than that of wild-type C1-Inh. These data suggest that the relatively weak inhibitory activity of C1-Inh is not the result of its short RSL. The short RSL of C1-Inh has, surprisingly, the optimal length for inhibition.

  16. Radical scavenging and angiotensin converting enzyme inhibitory activities of standardized extracts of Ficus racemosa stem bark.

    PubMed

    Ahmed, Faiyaz; Siddesha, Jalahalli M; Urooj, Asna; Vishwanath, Bannikuppe S

    2010-12-01

    The present study evaluated the radical scavenging and angiotensin converting enzyme (ACE) inhibitory activity of cold and hot aqueous extracts of Ficus racemosa (Moraceae) stem bark. The extracts were standardized using HPLC. Radical scavenging activity was determined using 1,1-diphenyl-2-picrylhydrazyl radical and angiotensin converting enzyme inhibitory activity using rabbit lung and partially purified porcine kidney ACE. HPLC profiles of cold aqueous extract (FRC) showed the presence of bergenin, an isocoumarin, while hot aqueous extract (FRH) was found to contain ferulic acid, kaempferol and coumarin in addition to bergenin. FRH showed significantly higher (p ≤ 0.01) radical scavenging activity than FRC and butylated hydroxytoluene (BHT), consequently resulting in a significantly lower (p ≤ 0.01) IC₅₀ value than FRC and BHT. Both the extracts exhibited a dose dependent inhibition of porcine kidney and rabbit lung ACE. FRH showed significantly higher (p ≤ 0.01) activity than FRC with lower IC(50) values of 1.36 and 1.91 μg/mL respectively, for porcine kidney and rabbit lung ACE, compared with those of FRC (128 and 291 μg/mL). Further, a significant correlation (r = 0.893; p ≤ 0.05) was observed between radical scavenging activity and ACE-inhibitory activity. This is the first report on the ACE-inhibitory activity of F. racemosa stem bark suggesting its potential to be utilized as a therapeutic alternative for hypertension. PMID:20564493

  17. Behavioral state-specific inhibitory postsynaptic potentials impinge on cat lumbar motoneurons during active sleep.

    PubMed

    Morales, F R; Boxer, P; Chase, M H

    1987-11-01

    High-gain intracellular records were obtained from lumbar motoneurons in intact, undrugged cats during naturally occurring states of wakefulness, quiet sleep, and active sleep. Spontaneous, discrete, inhibitory postsynaptic potentials (IPSPs) were found to impinge on lumbar motoneurons during all states of sleep and wakefulness. IPSPs which occurred during wakefulness and quiet sleep were of relatively low amplitude and had a low frequency of occurrence. During the state of active sleep there occurred a great increase in inhibitory input. This was the result of the appearance of large-amplitude IPSPs and of an increase in the frequency of low-amplitude IPSPs which were indistinguishable from those recorded during wakefulness and quiet sleep. In addition to a difference in amplitude, the time course of the large IPSPs recorded during active sleep further differentiated them from the smaller IPSPs recorded during wakefulness, quiet sleep, and active sleep; i.e., their rise-time and half-width were of longer duration and their rate-of-rise was significantly faster. We suggest that the large, active sleep-specific IPSPs reflect the activity of a group of inhibitory interneurons which are inactive during wakefulness and quiet sleep and which discharge during active sleep. These as yet unidentified interneurons would then serve as the last link in the brain stem-spinal cord inhibitory system which is responsible for producing muscle atonia during the state of active sleep. PMID:3666087

  18. Inhibitory Activities of Alkyl Syringates and Related Compounds on Aflatoxin Production.

    PubMed

    Furukawa, Tomohiro; Iimura, Kurin; Kimura, Taichi; Yamamoto, Toshiyoshi; Sakuda, Shohei

    2016-06-07

    Inhibitors of aflatoxin production of aflatoxigenic fungi are useful for preventing aflatoxin contamination in crops. As methyl syringate weakly inhibits aflatoxin production, aflatoxin production inhibitory activities of additional alkyl syringates with alkyl chains from ethyl to octyl were examined. Inhibitory activity toward aflatoxin production of Aspergillus flavus became stronger as the length of the alkyl chains on the esters became longer. Pentyl, hexyl, heptyl, and octyl syringates showed strong activity at 0.05 mM. Heptyl and octyl parabens, and octyl gallate also inhibited aflatoxin production as strongly as octyl syringate. Alkyl parabens and alkyl gallates inhibit the complex II activity of the mitochondrial respiration chain; thus, whether alkyl syringates inhibit complex II activity was examined. Inhibitory activities of alkyl syringates toward complex II also became stronger as the length of the alkyl chains increased. The complex II inhibitory activity of octyl syringate was comparable to that of octyl paraben and octyl gallate. These results suggest that alkyl syringates, alkyl parabens, and alkyl gallates, including commonly used food additives, are useful for aflatoxin control.

  19. Costus afer Possesses Carbohydrate Hydrolyzing Enzymes Inhibitory Activity and Antioxidant Capacity In Vitro

    PubMed Central

    Tchamgoue, Armelle D.; Tchokouaha, Lauve R. Y.; Tarkang, Protus A.; Kuiate, Jules-Roger; Agbor, Gabriel A.

    2015-01-01

    Diabetes mellitus is a metabolic disorder of glucose metabolism which correlates with postprandial hyperglycemia and oxidative stress. Control of blood glucose level is imperative in the management of diabetes. The present study tested the hypothesis that Costus afer, an antihyperglycemic medicinal plant, possesses inhibitory activity against carbohydrate hydrolyzing enzymes. Hexane, ethyl acetate, methanol, and water extracts were prepared from the leaf, stem, and rhizome of C. afer and subjected to phytochemical screening, assayed for α-amylase and α-glucosidase inhibitory activities and antioxidant capacity (determined by total phenolic and total flavonoids contents, ferric reducing antioxidant power (FRAP), and DPPH radical scavenging activity). All extracts inhibited α-amylase and α-glucosidase activities. Ethyl acetate rhizome and methanol leaf extracts exhibited the best inhibitory activity against α-amylase and α-glucosidase (IC50: 0.10 and 5.99 mg/mL), respectively. Kinetic analysis revealed two modes of enzyme inhibition (competitive and mixed). All extracts showed antioxidant capacity, with hexane extracts exhibiting the best activity. DPPH assay revealed that methanol leaf, rhizome, and ethyl acetate stem extracts (IC50 < 5 mg/mL) were the best antioxidants. The presence of bioactive compounds such as flavonoids, alkaloids, phenols, and tannins may account for the antioxidant capacity and carbohydrate hydrolyzing enzyme inhibitory activity of C. afer. PMID:26246844

  20. Inhibitory Activities of Alkyl Syringates and Related Compounds on Aflatoxin Production.

    PubMed

    Furukawa, Tomohiro; Iimura, Kurin; Kimura, Taichi; Yamamoto, Toshiyoshi; Sakuda, Shohei

    2016-01-01

    Inhibitors of aflatoxin production of aflatoxigenic fungi are useful for preventing aflatoxin contamination in crops. As methyl syringate weakly inhibits aflatoxin production, aflatoxin production inhibitory activities of additional alkyl syringates with alkyl chains from ethyl to octyl were examined. Inhibitory activity toward aflatoxin production of Aspergillus flavus became stronger as the length of the alkyl chains on the esters became longer. Pentyl, hexyl, heptyl, and octyl syringates showed strong activity at 0.05 mM. Heptyl and octyl parabens, and octyl gallate also inhibited aflatoxin production as strongly as octyl syringate. Alkyl parabens and alkyl gallates inhibit the complex II activity of the mitochondrial respiration chain; thus, whether alkyl syringates inhibit complex II activity was examined. Inhibitory activities of alkyl syringates toward complex II also became stronger as the length of the alkyl chains increased. The complex II inhibitory activity of octyl syringate was comparable to that of octyl paraben and octyl gallate. These results suggest that alkyl syringates, alkyl parabens, and alkyl gallates, including commonly used food additives, are useful for aflatoxin control. PMID:27338472

  1. Inhibitory Activities of Alkyl Syringates and Related Compounds on Aflatoxin Production

    PubMed Central

    Furukawa, Tomohiro; Iimura, Kurin; Kimura, Taichi; Yamamoto, Toshiyoshi; Sakuda, Shohei

    2016-01-01

    Inhibitors of aflatoxin production of aflatoxigenic fungi are useful for preventing aflatoxin contamination in crops. As methyl syringate weakly inhibits aflatoxin production, aflatoxin production inhibitory activities of additional alkyl syringates with alkyl chains from ethyl to octyl were examined. Inhibitory activity toward aflatoxin production of Aspergillus flavus became stronger as the length of the alkyl chains on the esters became longer. Pentyl, hexyl, heptyl, and octyl syringates showed strong activity at 0.05 mM. Heptyl and octyl parabens, and octyl gallate also inhibited aflatoxin production as strongly as octyl syringate. Alkyl parabens and alkyl gallates inhibit the complex II activity of the mitochondrial respiration chain; thus, whether alkyl syringates inhibit complex II activity was examined. Inhibitory activities of alkyl syringates toward complex II also became stronger as the length of the alkyl chains increased. The complex II inhibitory activity of octyl syringate was comparable to that of octyl paraben and octyl gallate. These results suggest that alkyl syringates, alkyl parabens, and alkyl gallates, including commonly used food additives, are useful for aflatoxin control. PMID:27338472

  2. Inhibitory Activity of Podophyllotoxin and Matairesinol-derivative Lignans on the Root Growth of Brassica campestris.

    PubMed

    Arimoto, M; Matsuura, S; Muro, C; Tsujibo, H; Matsumura, E; Yamaguchi, H; Inamori, Y

    1994-01-01

    All the lignans tested in a bioassay with Brassica campestris L. subsp. rapa Hook. fil. et Anders inhibited the root growth of this plant, except for deoxypicropodophyllin. The effects of functional groups in the molecule on the inhibitory activity of these compounds were studied. It is suggested that the methylenedioxyl group and the stereochemical configuration of the lactone junction of podophyllotoxin derivatives were closely related to the inhibitory activity. The O-methyl derivative of two hydroxyl groups of matairesinol greatly enhanced the inhibition of root growth in this plant.

  3. Lipase inhibitory activity of chlorophyll a, isofucosterol and saringosterol isolated from chloroform fraction of Sargassum thunbergii.

    PubMed

    Kim, Koth-Bong-Woo-Ri; Kim, Min-Ji; Ahn, Dong-Hyun

    2014-01-01

    Three compounds (chlorophyll a, isofucosterol and saringosterol) were isolated from chloroform fraction of Sargassum thunbergii extract. The three compounds had two- to fourfold lower lipase inhibitory activity than that of the CHCl3:MeOH (C:M) (100:1) fraction (fraction I, 83.78% at 1 mg/mL). These results suggested that the high lipase inhibitory activity of fraction I was attributable to the actions of the three compounds. Therefore, S. thunbergii has potential for application as an anti-obesity agent.

  4. GC-MS investigation and acetylcholinesterase inhibitory activity of Galanthus rizehensis.

    PubMed

    Sarikaya, Buket Bozkurt; Somer, Nehir Unver; Kaya, Gulen Irem; Onur, Mustafa Ali; Bastida, Jaume; Berkov, Strahil

    2013-01-01

    GC-MS (gas chromatography-mass spectrometry) analyses of alkaloids in the aerial parts and bulbs of Galanthus rizehensis Stern (Amaryllidaceae), collected during two different vegetation periods, was performed. Twenty three alkaloids were identified in four different alkaloid extracts. Acetylcholinesterase (AChE) inhibitory activities of the alkaloid extracts were tested. Both the highest alkaloid diversity and the most potent inhibitory activity (IC50 12.94 microg/ml) were obtained in extracts from the bulbs of G. rizehensis collected during the fruiting period.

  5. Inhibitory effects of cefotaxime on the activity of mushroom tyrosinase.

    PubMed

    Hu, Yong-Hua; Zhuang, Jiang-Xing; Yu, Feng; Cui, Yi; Yu, Wen-Wen; Yan, Chong-Ling; Chen, Qing-Xi

    2016-04-01

    Tyrosinase (EC 1.14.18.1) catalyzes both the hydroxylation of tyrosine into o-diphenols and the oxidation of o-diphenols into o-quinones that form brown or black pigments. In the present paper, cefotaxime, a cephalosporin antibacterial drug, was tested as an inhibitor of tyrosinase. The results show that cefotaxime inhibits both the monophenolase and diphenolase activities of tyrosinase. For the monophenolase activity, cefotaxime increased the lag time and decreased the steady-state activity with an IC50 of 3.2 mM. For the diphenolase activity, the inhibition by cefotaxime is reversible and mix-I type with an IC50 of 0.14 mM. The inhibition constants (K(I) and K(IS)) were determined to be 0.14 and 0.36 mM, respectively. The molecular mechanism of inhibition of tyrosinase by cefotaxime was determined by fluorescence quenching and molecular docking. The results demonstrated that cefotaxime was a static quencher of tyrosinase and that cefotaxime could dock favorably in the active site of tyrosinase. This research may offer a lead for designing and synthesizing novel and effective tyrosinase inhibitors in the future.

  6. Design and Synthesis of Norendoxifen Analogues with Dual Aromatase Inhibitory and Estrogen Receptor Modulatory Activities

    PubMed Central

    Lv, Wei; Liu, Jinzhong; Skaar, Todd C.; Flockhart, David A.; Cushman, Mark

    2015-01-01

    Both selective estrogen receptor modulators and aromatase inhibitors are widely used for the treatment of breast cancer. Compounds with both aromatase inhibitory and estrogen receptor modulatory activities could have special advantages for treatment of breast cancer. Our previous efforts led to the discovery of norendoxifen as the first compound with dual aromatase inhibitory and estrogen receptor binding activities. To optimize its efficacy and aromatase selectivity versus other cytochrome P450 enzymes, a series of structurally related norendoxifen analogues were designed and synthesized. The most potent compound, 4'-hydroxynorendoxifen (10), displayed elevated inhibitory potency against aromatase and enhanced affinity for estrogen receptors when compared to norendoxifen. The selectivity of 10 for aromatase versus other cytochrome P450 enzymes was also superior to norendoxifen. 4'-Hydroxynorendoxifen is therefore an interesting lead for further development to obtain new anticancer agents of potential value for the treatment of breast cancer. PMID:25751283

  7. Ultrasonic extraction of polysaccharides from Laminaria japonica and their antioxidative and glycosidase inhibitory activities

    NASA Astrophysics Data System (ADS)

    Wan, Peng; Yang, Xiaoman; Cai, Bingna; Chen, Hua; Sun, Huili; Chen, Deke; Pan, Jianyu

    2015-08-01

    In the present study, ultrasonic extraction technique (UET) is used to improve the yield of polysaccharides from Laminaria japonica (LJPs). And their antioxidative as well as glycosidase inhibitory activities are investigated. Box-Behnken design (BBD) combined with response surface methodology (RSM) is applied to optimize ultrasonic extraction for polysaccharides. The optimized conditions are obtained as extraction time at 54 min, ultrasonic power at 1050 W, extraction temperature at 80°C and ratio of material to solvent at 1:50 (g mL-1). Under these optimal ultrasonic extraction conditions, an actual experimental yield (5.75% ± 0.3%) is close to the predicted result (5.67%) with no significant difference ( P > 0.05). Vitro antioxidative and glycosidase inhibitory activities tests indicate that the crude polysaccharides (LJP) and two major ethanol precipitated fractions (LJP1 and LJP2) are in a concentration-dependent manner. LJP2 (30%-60% ethanol precipitated polysaccharides) possesses the strongest α-glucosidase inhibitory activity and moderate scavenging activity against hydroxyl radicals (66.09% ± 2.19%, 3.0 mg mL-1). Also, the inhibitory activity against α-glucosidase (59.08% ± 3.79%, 5.0 mg mL-1) is close to that of acarbose (63.99% ± 3.27%, 5.0 mg mL-1). LJP1 (30% ethanol precipitated polysaccharides) exhibits the strongest scavenging activity against hydroxyl radicals (99.80% ± 0.00%, 3.0 mg mL-1) and moderate α-glucosidase inhibitory activity (47.76% ± 1.92%, 5.0 mg mL-1). LJP shows the most remarkable DPPH scavenging activity (66.20% ± 0.11%, 5.0 mg mL-1) but weakest α-glucosidase inhibitory activity (37.77% ± 1.30%, 5.0 mg mL-1). However, all these LJPs exert weak inhibitory effects against α-amylase. These results show that UET is an effective method for extracting bioactive polysaccharides from seaweed materials. LJP1 and LJP2 can be developed as a potential ingredient in hypoglycemic agents or functional food for the management of

  8. Competition between activating and inhibitory processes in photobiology

    NASA Astrophysics Data System (ADS)

    Friedmann, Harry; Lubart, Rachel

    1996-01-01

    We discuss light-induced stimulation and inhibition of biological activity by means of three types of competing processes. In the visible region, these competing processes are the formation by photosensitization of reactive oxygen species (ROS) which stimulate the redox activity of the respiratory chain (RC) on the one hand, and intramolecular electronic- vibrational energy transfer from an endogenous photosensitizer to an enzyme of the RC, thereby bringing this enzyme into an inactive configuration and paralyzing the RC, on the other hand. Moreover, there is competition between stimulation of the redox activity of the RC by the ROS and a slower process where the enzymes of the RC react with the ROS, again paralyzing the RC. This paralysis of the RC plays a dominant role in photodynamic therapy, where exogenous photosensitizers together with a sufficiently large visible light-energy dose lead to overproduction of ROS. Finally, in the far-red region, there is competition between reactivation of the ATPase ion pumps in the cell membrane and inhibition of the enzymes in the RC as a result of vibrational overtone excitation. Photobioactivation is shown to lead to enhanced transient Ca2+ concentration increase (calcium oscillations) in the cytosol, thereby triggering further biological activity such as afflux of intercellular messengers which open gated ion channels in neighboring cells, producing calcium waves. Addition of ROS scavengers or quenchers such as SOD in the presence of catalase neutralizes photobiomodulation induced by visible light.

  9. Angiotensin converting enzyme inhibitory activity of soy protein subjected to selective hydrolysis and thermal processing.

    PubMed

    Margatan, Wynnie; Ruud, Kirsten; Wang, Qian; Markowski, Todd; Ismail, Baraem

    2013-04-10

    Soy protein isolate (SPI) and β-conglycinin- and glycinin-rich fractions were hydrolyzed using papain and pepsin. Protein denaturation, profiling, and peptide identification were carried out following DSC, SDS-PAGE, and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The in vitro antihypertensive activity of the hydrolysates was compared by determining the angiotensin converting enzyme (ACE) inhibitory activity. SDS-PAGE and LC-MS/MS analysis confirmed pepsin selectivity to glycinin and papain partial selectivity to β-conglycinin when the protein is least denatured. Both the papain-hydrolyzed SPI and the papain-hydrolyzed β-conglycinin-rich fraction had more than double the ACE inhibitory activity of that of pepsin-hydrolyzed SPI and pepsin-hydrolyzed glycinin-rich fraction. This observation indicated that β-conglycinin is a better precursor for antihypertensive peptides than glycinin. Additionally, the inhibitory activity of the papain-hydrolyzed SPI was thermally stable. This work demonstrated, for the first time, that selective hydrolysis to release peptides with ACE inhibitory activity can be accomplished without inducing extensive hydrolysis and performing unnecessary fractionation. PMID:23514371

  10. Pyochelin potentiates the inhibitory activity of gallium on Pseudomonas aeruginosa.

    PubMed

    Frangipani, Emanuela; Bonchi, Carlo; Minandri, Fabrizia; Imperi, Francesco; Visca, Paolo

    2014-09-01

    Gallium (Ga) is an iron mimetic that has successfully been repurposed for antibacterial chemotherapy. To improve the antibacterial potency of Ga on Pseudomonas aeruginosa, the effect of complexation with a variety of siderophores and synthetic chelators was tested. Ga complexed with the pyochelin siderophore (at a 1:2 ratio) was more efficient than Ga(NO3)3 in inhibiting P. aeruginosa growth, and its activity was dependent on increased Ga entrance into the cell through the pyochelin translocon.

  11. Pyochelin potentiates the inhibitory activity of gallium on Pseudomonas aeruginosa.

    PubMed

    Frangipani, Emanuela; Bonchi, Carlo; Minandri, Fabrizia; Imperi, Francesco; Visca, Paolo

    2014-09-01

    Gallium (Ga) is an iron mimetic that has successfully been repurposed for antibacterial chemotherapy. To improve the antibacterial potency of Ga on Pseudomonas aeruginosa, the effect of complexation with a variety of siderophores and synthetic chelators was tested. Ga complexed with the pyochelin siderophore (at a 1:2 ratio) was more efficient than Ga(NO3)3 in inhibiting P. aeruginosa growth, and its activity was dependent on increased Ga entrance into the cell through the pyochelin translocon. PMID:24957826

  12. COX-2 and sPLA2 inhibitory activity of aqueous extract and polyphenols of Rhizophora mangle (red mangrove).

    PubMed

    Marrero, Evangelina; Sánchez, Janet; de Armas, Elizabeth; Escobar, Arturo; Melchor, Gleiby; Abad, M J; Bermejo, Paulina; Villar, Angel M; Megías, J; Alcaraz, Maria J

    2006-06-01

    The aqueous extract of Rhizophora mangle bark and its polyphenolic fractions showed remarkable in vitro antiinflammatory activity in a preliminary study. The low molecular weight fraction exhibited cyclooxygenase-2 inhibitory activity while the total aqueous extract and the low molecular weight fraction showed secretory phospholipase A(2) inhibitory activity. PMID:16698195

  13. An Update on Natural Products with Carbonic Anhydrase Inhibitory Activity.

    PubMed

    Karioti, Anastasia; Carta, Fabrizio; Supuran, Claudiu T

    2016-01-01

    Carbonic anhydrases (CAs, EC 4.2.1.1) catalyze the fundamental reaction of CO2 hydration in all living organisms, being actively involved in the regulation of a plethora of patho/physiological processes. They represent a typical example of enzyme convergent evolution, as six genetically unrelated families of such enzymes were described so far. It is more than 70 years that synthetic compounds, mainly sulfonamides, have been used in clinical practice as diuretics and systemic acting antiglaucoma drugs. Recent studies using natural product libraries and isolated constituents from natural sources (such as fungi and plants) have disclosed novel chemotypes possessing carbonic anhydrase inhibition activities. These natural sources offer new opportunities in the search for new and more effective carbonic anhydrase inhibitors, and may serve as new leads for the design and development of future drugs. This review will discuss the most recent advances in the search of naturally occurring products and their synthetic derivatives that inhibit the CAs and their mechanisms of action at molecular level. Plant extracts are not considered in the present review. PMID:26654592

  14. Matrix metalloproteinase-1 inhibitory activity of Kaempferia pandurata Roxb.

    PubMed

    Shim, Jae-Seok; Choi, Eun-Jung; Lee, Chan-Woo; Kim, Han-Sung; Hwang, Jae-Kwan

    2009-06-01

    Matrix metalloproteinase (MMP)-1 is a superfamily of zinc-dependent endopeptidases that are capable of degrading all components of the extracellular matrix. Kaempferia pandurata extract (0.01-0.5 microg/mL) significantly reduced the expression of MMP-1 and induced the expression of type 1 procollagen at the protein and mRNA levels in a dose-dependent manner. Ultraviolet (UV)-induced MMP-1 initiates cleavage of fibrillar collagen. Once cleaved by MMP-1, collagen can be further degraded by elevated levels of MMP-3 and MMP-9. It was found that increased MMP-1 expression due to UV irradiation was mediated by activation of mitogen-activated protein kinases such as extracellular-regulated kinase (ERK), Jun N-terminal kinase (JNK), and p38 kinase. Treatment of K. pandurata extract in the range of 0.01-0.5 microg/mL inhibited the UV-induced phosphorylations of ERK, JNK, and p38, respectively. Moreover, inhibition of phosphorylated ERK, JNK, and p38 by K. pandurata extract resulted in decreased c-Fos expression and c-Jun phosphorylation induced by UV light. The results strongly suggest that K. pandurata is potentially useful for the prevention and treatment of skin aging.

  15. Evaluation of the Antioxidant Activities and Tyrosinase Inhibitory Property from Mycelium Culture Extracts

    PubMed Central

    Park, Ki Moon; Kwon, Kyung Min; Lee, Seung Ho

    2015-01-01

    Since mushrooms have many bioactive components, they have been used as components in folk medicine. Because mycelium has an advantage when it comes to large-scale production, this study aimed to evaluate the antioxidant properties and anti-tyrosinase activity from 55 mycelia in culture media. Relatively high 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging capacity was detected from the ethanol extract of culture media including mycelium (EECiM) of Morchella esculenta var. esculenta (MEVE), Auricularia polytricha (APO), Tremella aurantia (TAU), Volvariella bombycina (VBO), and Oudemansiella sp. (Osp), which also showed strong reducing power and inhibitory activity in relation to the thiobarbituric acid (TBA) value. On the other hand, relatively high tyrosinase inhibitory activity was detected in Inonotus mikadoi (IMI), Coriolus versicolor (CVE), Volvariella volvacea (VVO), Panellus serotinus (PSE), Auricularia auricula (AAU), and Fomitopsis sp. (Fsp). Interestingly, the APO EECiM exhibited the highest DPPH radical scavenging rate (77.5 ± 4.3%) and reducing power (1.18 ± 0.041), while the highest inhibitory power of the TBA value and antityrosinase activity were detected in that of TAU (64.5 ± 4.1%) and IMI (46.0 ± 7.5%), respectively. Overall, our study suggested potential candidates for EECiMs that exhibited powerful antioxidant and tyrosinase inhibitory properties and might be used as natural antioxidant tyrosinase inhibitor. PMID:26345142

  16. Nobiletin metabolites: synthesis and inhibitory activity against matrix metalloproteinase-9 production.

    PubMed

    Oshitari, Tetsuta; Okuyama, Yuji; Miyata, Yoshiki; Kosano, Hiroshi; Takahashi, Hideyo; Natsugari, Hideaki

    2011-08-01

    A divergent synthesis of nobiletin metabolites was developed through highly oxygenated acetophenone derivative. We used commercially available methyl 3,4,5-trimethoxybenzoate as a starting material for concise preparation of the key intermediate, 2'-hydroxy-3',4',5',6'-tetramethoxyacetophenone (I). These metabolites showed strong inhibitory activity against matrix metalloproteinase-9 production in human lens epithelial cells.

  17. Phenolic constituents of Carex vulpinoidea seeds and their tyrosinase inhibitory activities.

    PubMed

    Niesen, Daniel B; Ma, Hang; Yuan, Tao; Bach, Alvin C; Henry, Geneive E; Seeram, Navindra P

    2015-03-01

    Two new phenolics, a stilbenoid, vulpinoideol A (1), and a chalcone, vulpinoideol B (2), along with ten known compounds (3-12) were isolated from Carex vulpinoidea Michx. seeds. The structures of compounds 1-12 were elucidated based on spectrometric and spectroscopic analyses including HRESIMS, 1D and 2D NMR data. All compounds were evaluated for their tyrosinase enzyme inhibitory activities.

  18. Bioactive diterpenoids from Trigonostemon chinensis: Structures, NO inhibitory activities, and interactions with iNOS.

    PubMed

    Xu, Jing; Peng, Maoqin; Sun, Xiaocong; Liu, Xingyu; Tong, Ling; Su, Guochen; Ohizumi, Yasushi; Lee, Dongho; Guo, Yuanqiang

    2016-10-01

    A phytochemical investigation to obtain new NO inhibitors led to the isolation of two new (1 and 2) and four known (3-6) diterpenoids from Trigonostemon chinensis. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analyses, and the absolute configurations of new compounds were established by experimental and calculated ECD spectra. The inhibitory activities on lipopolysaccharide-induced NO production in murine microglial BV-2 cells of these diterpenoids were evaluated, and all of the compounds showed inhibitory effects. The interactions of bioactive compounds with iNOS protein were also studied by molecular docking. PMID:27570243

  19. Activity Prediction and Molecular Mechanism of Bovine Blood Derived Angiotensin I-Converting Enzyme Inhibitory Peptides

    PubMed Central

    Zhang, Ting; Nie, Shaoping; Liu, Boqun; Yu, Yiding; Zhang, Yan; Liu, Jingbo

    2015-01-01

    Development of angiotensin I-converting enzyme (ACE, EC 3.4.15.1) inhibitory peptides from food protein is under extensive research as alternative for the prevention of hypertension. However, it is difficult to identify peptides released from food sources. To accelerate the progress of peptide identification, a three layer back propagation neural network model was established to predict the ACE-inhibitory activity of pentapeptides derived from bovine hemoglobin by simulated enzyme digestion. The pentapeptide WTQRF has the best predicted value with experimental IC50 23.93 μM. The potential molecular mechanism of the WTQRF / ACE interaction was investigated by flexible docking. PMID:25768442

  20. Activity prediction and molecular mechanism of bovine blood derived angiotensin I-converting enzyme inhibitory peptides.

    PubMed

    Zhang, Ting; Nie, Shaoping; Liu, Boqun; Yu, Yiding; Zhang, Yan; Liu, Jingbo

    2015-01-01

    Development of angiotensin I-converting enzyme (ACE, EC 3.4.15.1) inhibitory peptides from food protein is under extensive research as alternative for the prevention of hypertension. However, it is difficult to identify peptides released from food sources. To accelerate the progress of peptide identification, a three layer back propagation neural network model was established to predict the ACE-inhibitory activity of pentapeptides derived from bovine hemoglobin by simulated enzyme digestion. The pentapeptide WTQRF has the best predicted value with experimental IC50 23.93 μM. The potential molecular mechanism of the WTQRF / ACE interaction was investigated by flexible docking. PMID:25768442

  1. Blumeaenes A-J, sesquiterpenoid esters from Blumea balsamifera with NO inhibitory activity.

    PubMed

    Chen, Ming; Qin, Jiang-Jiang; Fu, Jian-Jun; Hu, Xiao-Jia; Liu, Xiao-Hua; Zhang, Wei-Dong; Jin, Hui-Zi

    2010-06-01

    Chemical examination of the ethanol extract of the aerial parts of Blumea balsamifera led to the isolation of ten new sesquiterpenoid esters, blumeaenes A-J (1- 10), with 13 known flavonoids. Their structures were determined mainly by use of 1D and 2D NMR spectroscopic techniques. All sesquiterpenoid esters were tested for their inhibitory activity against LPS-induced NO production in RAW264.7 macrophages. Compounds 1, 4 and 5 showed slight inhibitory effect on the production of NO with IC(50) values of 40.06, 46.35 and 57.80 microg/mL, respectively. PMID:20101563

  2. Protein glycation inhibitory activity and antioxidant capacity of clove extract.

    PubMed

    Suantawee, Tanyawan; Wesarachanon, Krittaporn; Anantsuphasak, Kanokphat; Daenphetploy, Tanuch; Thien-Ngern, Sroshin; Thilavech, Thavaree; Pasukamonset, Porntip; Ngamukote, Sathaporn; Adisakwattana, Sirichai

    2015-06-01

    Syzygium aromaticum (L.) (clove) is one of the most widely cultivated spices in many tropical countries. The aim of this study was to determine the phytochemical content, the antioxidant properties and the antiglycation properties of aqueous extract of clove against fructose-mediated protein glycation and oxidation. The result showed that the content of total phenolics and flavonoids in clove extract was 239.58 ± 0.70 mg gallic acid equivalents/g dried extract and 65.67 ± 0.01 mg catechin equivalents/g dried extract, respectively. In addition, clove exhibited antioxidant properties including DPPH radical scavenging activity (IC50 = 0.29 ± 0.01 mg/ml), Trolox equivalent antioxidant capacity (4.69 ± 0.03 μmol Trolox equivalents/mg dried extract), ferric reducing antioxidant power (20.55 ± 0.11 μmol ascorbic acid equivalents/mg dried extract), Oxygen radical absorbance capacity (31.12 ± 0.21 μmol Trolox equivalents/mg dried extract), hydroxyl radical scavenging activity (0.15 ± 0.04 mg Trolox equivalents/mg dried extract), and superoxide radical scavenging activity (18.82 ± 0.50 mg Trolox equivalents/mg dried extract). The aqueous extract of clove (0.25-1.00 mg/ml) significantly inhibited the formation of fluorescent advanced glycation end products (AGEs) and non-fluorescent AGEs (N(ɛ)-(carboxymethyl) lysine (CML)) in glycated BSA during 4 weeks of incubation. The extract also markedly prevented oxidation-induced protein damage by decreasing protein carbonyl formation and protecting against the loss of protein thiol group. These results clearly demonstrated that a polyphenol enriched clove extract, owing to its antioxidant, was capable to inhibit the formation of AGEs and protein glycation. The findings might lead to the possibility of using the clove extract for targeting diabetic complications.

  3. Urease Inhibitory Activities of some Commonly Consumed Herbal Medicines.

    PubMed

    Mahernia, Shabnam; Bagherzadeh, Kowsar; Mojab, Faraz; Amanlou, Massoud

    2015-01-01

    Urease enzyme has a crucial role in the persistent habitation of Helicobacter pylori (H. pylori) that induces gastrointestinal diseases, in particular gastritis, duodenal, peptic ulcer, and gastric cancer. Plants have long been utilized as the biggest source of substances with medicinal properties from natural origin and therefore result in less toxicity and adverse side effects upon usage. 15 medicinal plant extracts were examined against Jack bean urease activity by Berthelot reaction. Each herb was extracted using 80% aqueous methanol. The more effective extracts were further tested and their IC50 values were determined. Three plant extracts including Ginkgo biloba, Rhus coriaria, and Matricaria inodora were found to be the most effective ones with IC50 values of 36.17, 80.29, and 100.6 μg/mL, respectively. PMID:26330884

  4. Urease Inhibitory Activities of some Commonly Consumed Herbal Medicines

    PubMed Central

    Mahernia, Shabnam; Bagherzadeh, Kowsar; Mojab, Faraz; Amanlou, Massoud

    2015-01-01

    Urease enzyme has a crucial role in the persistent habitation of Helicobacter pylori (H. pylori) that induces gastrointestinal diseases, in particular gastritis, duodenal, peptic ulcer, and gastric cancer. Plants have long been utilized as the biggest source of substances with medicinal properties from natural origin and therefore result in less toxicity and adverse side effects upon usage. 15 medicinal plant extracts were examined against Jack bean urease activity by Berthelot reaction. Each herb was extracted using 80% aqueous methanol. The more effective extracts were further tested and their IC50 values were determined. Three plant extracts including Ginkgo biloba, Rhus coriaria, and Matricaria inodora were found to be the most effective ones with IC50 values of 36.17, 80.29, and 100.6 μg/mL, respectively. PMID:26330884

  5. Natural Product Compounds with Aromatase Inhibitory Activity: An Update

    PubMed Central

    Balunas, Marcy J.; Kinghorn, A. Douglas

    2010-01-01

    Several synthetic aromatase inhibitors are currently in clinical use for the treatment of postmenopausal women with hormone-receptor positive breast cancer. However, these treatments may lead to untoward side effects and so a search for new aromatase inhibitors continues, especially those for which the activity is promoter-specific, targeting the breast-specific promoters I.3 and II. Recently, numerous natural product compounds have been found to inhibit aromatase in non-cellular, cellular, and in vivo studies. These investigations, covering the last two years, as well as additional studies that have focused on the evaluation of natural product compounds as promoter-specific aromatase inhibitors or as aromatase inducers, are described in this review. PMID:20635310

  6. A novel inhibitory nucleo-cortical circuit controls cerebellar Golgi cell activity

    PubMed Central

    Ankri, Lea; Husson, Zoé; Pietrajtis, Katarzyna; Proville, Rémi; Léna, Clément; Yarom, Yosef; Dieudonné, Stéphane; Uusisaari, Marylka Yoe

    2015-01-01

    The cerebellum, a crucial center for motor coordination, is composed of a cortex and several nuclei. The main mode of interaction between these two parts is considered to be formed by the inhibitory control of the nuclei by cortical Purkinje neurons. We now amend this view by showing that inhibitory GABA-glycinergic neurons of the cerebellar nuclei (CN) project profusely into the cerebellar cortex, where they make synaptic contacts on a GABAergic subpopulation of cerebellar Golgi cells. These spontaneously firing Golgi cells are inhibited by optogenetic activation of the inhibitory nucleo-cortical fibers both in vitro and in vivo. Our data suggest that the CN may contribute to the functional recruitment of the cerebellar cortex by decreasing Golgi cell inhibition onto granule cells. DOI: http://dx.doi.org/10.7554/eLife.06262.001 PMID:25965178

  7. Angiotensin I-Converting Enzyme (ACE) Inhibitory Activity and ACE Inhibitory Peptides of Salmon (Salmo salar) Protein Hydrolysates Obtained by Human and Porcine Gastrointestinal Enzymes

    PubMed Central

    Darewicz, Małgorzata; Borawska, Justyna; Vegarud, Gerd E.; Minkiewicz, Piotr; Iwaniak, Anna

    2014-01-01

    The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE) inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes) and ex vivo digestion (with human gastrointestinal enzymes). Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50%) of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes. PMID:25123137

  8. Angiotensin I-converting enzyme (ACE) inhibitory activity and ACE inhibitory peptides of salmon (Salmo salar) protein hydrolysates obtained by human and porcine gastrointestinal enzymes.

    PubMed

    Darewicz, Małgorzata; Borawska, Justyna; Vegarud, Gerd E; Minkiewicz, Piotr; Iwaniak, Anna

    2014-08-13

    The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE) inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes) and ex vivo digestion (with human gastrointestinal enzymes). Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50%) of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes.

  9. Synthesis and quorum sensing inhibitory activity of key phenolic compounds of ginger and their derivatives.

    PubMed

    Kumar, N Vijendra; Murthy, Pushpa S; Manjunatha, J R; Bettadaiah, B K

    2014-09-15

    Phenolic components of ginger (Zingiber officinale Roscoe) viz. [6]-gingerol, [6]-shogaol and zingerone exhibited quorum sensing inhibitory activity (QSI) against Chromobacterium violaceum and Pseudomonas aeruginosa. The inhibitory activity of all the compounds was studied by zone inhibition, pyocyanin, and violacein assay. All the compounds displayed good inhibition at 500ppm. [6]-Azashogaol, a new derivative of [6]-shogaol has been synthesized by Beckmann rearrangement of its oxime in the presence of ZnCl2. The structure elucidation of this new derivative was carried out by 1D ((1)H NMR and (13)C NMR) and 2D-NMR (COSY, HSQC and NOESY) spectral studies. This compound showed good QSI activity against P. aeruginosa. An isoxazoline derivative of [6]-gingerol was prepared and it exhibited good QSI activity. Present study illustrated that, the phenolic compounds of ginger and their derivatives form a class of compounds with promising QSI activity. PMID:24767081

  10. Inhibitory effect of morinda citrifolia L. On lipoprotein lipase activity.

    PubMed

    Pak-Dek, M S; Abdul-Hamid, A; Osman, A; Soh, C S

    2008-10-01

    Efficacy of Morinda citrifolia L. leaf (MLE) and fruit extracts (MFE) in inhibiting lipoprotein lipase (LPL) was determined in vitro. The result of the study showed that the highest inhibition on the LPL activity was exhibited by MLE (66%+/- 2.1%), which is significantly higher than that demonstrated by MFE (54.5%+/- 2.5%), green tea extract (GTE) (54.5%+/- 2.6%), and catechin (43.6%+/- 6.1%). Percent of LPL inhibition increase with concentration of the extracts. Quantitative analysis of the extracts revealed the presence of high levels of (+)-catechin at 63.5 +/- 17 and 53.7 +/- 5.7 mg/g in MLE and MFE, respectively, although not as high as that found in GTE (530.6 +/- 42 mg/g). Appreciable amount of epicatechin was found in all extracts tested, while rutin was only found in MLE and MFE. The study suggested that both leaf and fruit of M. citrifolia may be used as antiobesity agents in body weight management.

  11. Estimation of excitatory and inhibitory synaptic conductance variations in motoneurons during locomotor-like rhythmic activity.

    PubMed

    Kobayashi, Ryota; Nishimaru, Hiroshi; Nishijo, Hisao

    2016-10-29

    The rhythmic activity of motoneurons (MNs) that underlies locomotion in mammals is generated by synaptic inputs from the locomotor network in the spinal cord. Thus, the quantitative estimation of excitatory and inhibitory synaptic conductances is essential to understand the mechanism by which the network generates the functional motor output. Conductance estimation is obtained from the voltage-current relationship measured by voltage-clamp- or current-clamp-recording with knowledge of the leak parameters of the recorded neuron. However, it is often difficult to obtain sufficient data to estimate synaptic conductances due to technical difficulties in electrophysiological experiments using in vivo or in vitro preparations. To address this problem, we estimated the average variations in excitatory and inhibitory synaptic conductance during a locomotion cycle from a single voltage trace without measuring the leak parameters. We found that the conductance variations can be accurately reconstructed from a voltage trace of 10 cycles by analyzing synthetic data generated from a computational model. Next, the conductance variations were estimated from mouse spinal MNs in vitro during drug-induced-locomotor-like activity. We found that the peak of excitatory conductance occurred during the depolarizing phase of the locomotor cycle, whereas the peak of inhibitory conductance occurred during the hyperpolarizing phase. These results suggest that the locomotor-like activity is generated by push-pull modulation via excitatory and inhibitory synaptic inputs. PMID:27561702

  12. Inhibitory effect of several fluoroquinolones on hepatic microsomal cytochrome P-450 1A activities in dogs.

    PubMed

    Regmi, N L; Abd El-Aty, A M; Kuroha, M; Nakamura, M; Shimoda, M

    2005-12-01

    We examined inhibitory effects of ofloxacin (OFX), orbifloxacin (OBFX), ciprofloxacin (CFX), enrofloxacin (EFX) and norfloxacin (NFX) on cytochrome P-450 1A (CYP1A) activities using hepatic microsomes from four beagle dogs. Ethoxyresorufin O-de-ethylation was referred as CYP1A activities. All the fluoroquinolones inhibited the reaction in a noncompetitive manner. The determined inhibitory constants were the followings; 10.1 +/- 3.8 mM for OFX, 6.43 +/- 2.01 mM for OBFX, 0.726 +/- 0.134 mM for CFX, 4.06 +/- 1.19 mM for EFX and 4.75 +/- 1.63 mM for NFX respectively. As these values are >100-fold of plasma concentrations after a clinical single dose of the fluoroquinolones, it is suggested that the inhibitory effect on CYP1A activities is not so high to elicit drug-drug interaction with CYP1A substrates, when these fluoroquinolones are co-administered. Mechanism based inhibition was also examined in this study. Of the five fluoroquinolones examined, OFX, OBFX and CFX had this inhibition manner. As this inhibition is irreversible, inhibitory effects of the three fluoroquinolones may accumulate, when they are repeatedly administered. Therefore, OFX, OBFX and CFX may result in substantial drug-drug interaction with a CYP1A substrate even in clinical states. As EFX is metabolized to CFX in the body, it may also have the same possibility.

  13. Sugar compositions, α-glucosidase inhibitory and amylase inhibitory activities of polysaccharides from leaves and flowers of Camellia sinensis obtained by different extraction methods.

    PubMed

    Wang, Yuanfeng; Yang, Zhiwei; Wei, Xinlin

    2010-11-01

    The sugar compositions, α-glucosidase inhibitory and α-amylase inhibitory activities of polysaccharides from leaves and flowers of green tea (Camellia sinensis) obtained by hot water extraction (HWE), boiled water extraction (BWE) and enzymatic extraction (EE) were investigated. The yields, sugar contents and monosaccharide compositions of tea leaves polysaccharides (TLPS) and tea flower polysaccharides (TFPS) were all significantly affected by extraction methods. The contents of acidic polysaccharides (APS) extracted by BWE and EE were both much more than those by HWE. The yields of TLPS and TFPS were determined as EE>BWE>HWE. Enzyme and higher temperature could improve the contents of APS and yields of TLPS and TFPS. TLPS and TFPS were all mainly composed of Rha, Ara, Gal, Glu and GalA, very little molar contents of GluA, Xyl and Man. It seemed that enzyme extraction could be more conducive to increase the content of Ara, Gal and GaLA. The molecular weights of TFPS were larger than those of TLPS. The molecular weights of polysaccharides obtained by EE decreased. Proteins in tea leaves and tea flowers might be decomposed by EE by observing UV peaks and IR absorption. peaks. The α-glucosidase inhibitory and amylase inhibitory activities of TLPS and TFPS obtained by EE were lower than those by water extracted method. The inhibitory percentages of TLPS and TFPS against α-amylase were all lower than α-glucosidase for different extractions.

  14. Effect of Jatropha curcas Peptide Fractions on the Angiotensin I-Converting Enzyme Inhibitory Activity

    PubMed Central

    Segura-Campos, Maira R.; Peralta-González, Fanny; Castellanos-Ruelas, Arturo; Chel-Guerrero, Luis A.; Betancur-Ancona, David A.

    2013-01-01

    Hypertension is one of the most common worldwide diseases in humans. Angiotensin I-converting enzyme (ACE) plays an important role in regulating blood pressure and hypertension. An evaluation was done on the effect of Alcalase hydrolysis of defatted Jatropha curcas kernel meal on ACE inhibitory activity in the resulting hydrolysate and its purified fractions. Alcalase exhibited broad specificity and produced a protein hydrolysate with a 21.35% degree of hydrolysis and 34.87% ACE inhibition. Ultrafiltration of the hydrolysate produced peptide fractions with increased biological activity (24.46–61.41%). Hydrophobic residues contributed substantially to the peptides' inhibitory potency. The 5–10 and <1 kDa fractions were selected for further fractionation by gel filtration chromatography. ACE inhibitory activity (%) ranged from 22.66 to 45.96% with the 5–10 kDa ultrafiltered fraction and from 36.91 to 55.83% with the <1 kDa ultrafiltered fraction. The highest ACE inhibitory activity was observed in F2 (IC50 = 6.7 μg/mL) from the 5–10 kDa fraction and F1 (IC50 = 4.78 μg/mL) from the <1 kDa fraction. ACE inhibitory fractions from Jatropha kernel have potential applications in alternative hypertension therapies, adding a new application for the Jatropha plant protein fraction and improving the financial viability and sustainability of a Jatropha-based biodiesel industry. PMID:24224169

  15. Chemical Evidence for Potent Xanthine Oxidase Inhibitory Activity of Ethyl Acetate Extract of Citrus aurantium L. Dried Immature Fruits.

    PubMed

    Liu, Kun; Wang, Wei; Guo, Bing-Hua; Gao, Hua; Liu, Yang; Liu, Xiao-Hong; Yao, Hui-Li; Cheng, Kun

    2016-03-02

    Xanthine oxidase is a key enzyme which can catalyze hypoxanthine and xanthine to uric acid causing hyperuricemia in humans. Xanthine oxidase inhibitory activities of 24 organic extracts of four species belonging to Citrus genus of the family Rutaceae were assayed in vitro. Since the ethyl acetate extract of C. aurantium dried immature fruits showed the highest xanthine oxidase inhibitory activity, chemical evidence for the potent inhibitory activity was clarified on the basis of structure identification of the active constituents. Five flavanones and two polymethoxyflavones were isolated and evaluated for inhibitory activity against xanthine oxidase in vitro. Of the compounds, hesperetin showed more potent inhibitory activity with an IC50 value of 16.48 μM. For the first time, this study provides a rational basis for the use of C. aurantium dried immature fruits against hyperuricemia.

  16. Antioxidant, antimicrobial and tyrosinase inhibitory activities of xanthones isolated from Artocarpus obtusus F.M. Jarrett.

    PubMed

    Hashim, Najihah Mohd; Rahmani, Mawardi; Ee, Gwendoline Cheng Lian; Sukari, Mohd Aspollah; Yahayu, Maizatulakmal; Amin, Muhamad Aizat Mohd; Ali, Abd Manaf; Go, Rusea

    2012-05-21

    One of the most promising plants in biological screening test results of thirteen Artocarpus species was Artocarpus obtusus FM Jarrett and detailed phytochemical investigation of powdered dried bark of the plant has led to the isolation and identification of three xanthones; pyranocycloartobiloxanthone A (1), dihydroartoindonesianin C (2) and pyranocycloartobiloxanthone B (3). These compounds were screened for antioxidant, antimicrobial and tyrosinase inhibitory activities. Pyranocycloartobiloxanthone A (1) exhibited a strong free radical scavenger towards DPPH free radicals with IC50 value of 2 µg/mL with prominent discoloration observed in comparison with standard ascorbic acid, α-tocopherol and quercetin, The compound also exhibited antibacterial activity against methicillin resistant Staphylococcus aureus (ATCC3359) and Bacillus subtilis (clinically isolated) with inhibition zone of 20 and 12 mm, respectively. However the other two xanthones were found to be inactive. For the tyrosinase inhibitory activity, again compound (1) displayed strong activity comparable with the standard kojic acid.

  17. Secondary Metabolites Produced by an Endophytic Fungus Pestalotiopsis sydowiana and Their 20S Proteasome Inhibitory Activities.

    PubMed

    Xia, Xuekui; Kim, Soonok; Liu, Changheng; Shim, Sang Hee

    2016-01-01

    Fungal endophytes have attracted attention due to their functional diversity. Secondary metabolites produced by Pestalotiopsis sydowiana from a halophyte, Phragmites communis Trinus, were investigated. Eleven compounds, including four penicillide derivatives (1-4) and seven α-pyrone analogues (5-10) were isolated from cultures of P. sydowiana. The compounds were identified based on spectroscopic data. The inhibitory activities against the 20S proteasome were evaluated. Compounds 1-3, 5, and 9-10 showed modest proteasome inhibition activities, while compound 8 showed strong activity with an IC50 of 1.2 ± 0.3 μM. This is the first study on the secondary metabolites produced by P. sydowiana and their proteasome inhibitory activities. The endophytic fungus P. sydowiana might be a good resource for proteasome inhibitors. PMID:27447600

  18. 2'-Epi-uscharin from the latex of Calotropis gigantea with HIF-1 inhibitory activity.

    PubMed

    Parhira, Supawadee; Zhu, Guo-Yuan; Jiang, Ren-Wang; Liu, Liang; Bai, Li-Ping; Jiang, Zhi-Hong

    2014-04-23

    Two stereoisomeric cardenolides, uscharin (1) and a new compound, 2'-epi-uscharin (2), were isolated from the latex of Calotropis gigantea (Asclepiadaceae). Their structures were fully elucidated based on their spectroscopic data, X-ray crystallographic data and chemical evidences. Both epimers (1 and 2) exhibited strong inhibitory effects on HIF-1 activity with different magnitudes. Compound 1 showed much more potent activity than 2 and digoxin, a well-known HIF-1 inhibitor. Discrepancy in potencies between 1 and 2 revealed the contribution of a β-configuration of 2' hydroxyl moiety for HIF-1 inhibitory activity. This is a first report of the activity of HIF-1 inhibition of thiazoline ring-containing cardenolides.

  19. 2‧-Epi-uscharin from the Latex of Calotropis gigantea with HIF-1 Inhibitory Activity

    NASA Astrophysics Data System (ADS)

    Parhira, Supawadee; Zhu, Guo-Yuan; Jiang, Ren-Wang; Liu, Liang; Bai, Li-Ping; Jiang, Zhi-Hong

    2014-04-01

    Two stereoisomeric cardenolides, uscharin (1) and a new compound, 2'-epi-uscharin (2), were isolated from the latex of Calotropis gigantea (Asclepiadaceae). Their structures were fully elucidated based on their spectroscopic data, X-ray crystallographic data and chemical evidences. Both epimers (1 and 2) exhibited strong inhibitory effects on HIF-1 activity with different magnitudes. Compound 1 showed much more potent activity than 2 and digoxin, a well-known HIF-1 inhibitor. Discrepancy in potencies between 1 and 2 revealed the contribution of a β-configuration of 2' hydroxyl moiety for HIF-1 inhibitory activity. This is a first report of the activity of HIF-1 inhibition of thiazoline ring-containing cardenolides.

  20. Inhibitory role of monovalent ions on rat brain cortex adenylyl cyclase activity.

    PubMed

    Nikolic, Ivana; Mitrovic, Marina; Zelen, Ivanka; Zaric, Milan; Kastratovic, Tatjana; Stanojevic, Marijana; Nenadovic, Milutin; Stojanovic, Tomislav

    2013-10-01

    Adenylyl cyclases, comprise of a large family of enzymes that catalyze synthesis of the cyclic AMP from ATP. The aim of our study was to determine the effect of monovalent ions on both basal, stimulated adenylate cyclase EC 4.6.1.1 (AC) activity and C unit of AC and on GTPase active G-protein in the synaptic membranes of rat brain cortex. The effect of ion concentration from 30 to 200 mM (1 mM MgCl2) showed dose-dependent and significant inhibition of the basal AC activity, stimulated and unstimulated C unit activity. Stimulation of AC with 5 μM GTPγS in the presence of 50-200 mM of tested salts showed inhibitory effect on the AC activity. From our results it could be postulated that the investigated monovalent ions exert inhibitory effect on the AC complex activity by affecting the intermolecular interaction of the activated α subunit of G/F protein and the C unit of AC complex an inhibitory influence of tested monovalent ions on these molecular interaction.

  1. Effect of hyperoxaluria on the inhibitory activity of a 45-kD urinary protein.

    PubMed

    Selvam, Ramasamy; Balakrishnan, Selvakumar; Kalaiselvi, Periandavan

    2002-02-01

    Proteins are thought to play a major role in stone formation and structurally abnormal proteins have been reported to be present in the urine of stone formers. This study was aimed to determine whether hyperoxaluria modifies the kinetic properties of urinary inhibitory proteins. Hyperoxaluria was induced by feeding 1% ethylene glycol to rats. Oxalate, uric acid and calcium excretion were increased progressively during hyperoxaluria, while magnesium level was decreased. Urinary proteins were separated on a DEAE-cellulose column by eluting with stepwise increasing salt concentration in 0.05 M Tris-HCl buffer (pH 7.0). Each protein fraction was studied for its crystallization inhibitory potential by the spectrophotometric method. The protein eluted in 0.3 M NaCl containing buffer had the maximal nucleation as well as inhibitory activity. The protein had a molecular weight of 45 kD. In hyperoxaluria, the urinary excretion of this protein significantly increased. In the crystal growth assay, the control rat 45-kD protein inhibited nucleation by 75% and aggregation by 100%. In contrast, it is very interesting to note that the protein derived from 28th day hyperoxaluric urine, behaved as a promoter of nucleation (-113%, percentage inhibition) and weak inhibitor of aggregation (28%). A significantly high negative correlation (r = -0.97) between oxalate excretion and the inhibitory activity of the 45-kD protein was observed suggesting a modification of the protein by oxalate. PMID:11818706

  2. Telomerase inhibitory effects of medicinal mushrooms and lichens, and their anticancer activity.

    PubMed

    Xu, Baojun; Li, Chantian; Sung, Changkeun

    2014-01-01

    Telomerase has been widely accepted as a cancer marker and a promising therapeutic target for novel anticancer drugs. The aim of this study was to investigate the in vitro telomerase inhibitory effects of mushrooms and their anticancer properties. The inhibitory effects of mushrooms and lichens against telomerase activity of HL-60 cells were systematically assessed using polymerase chain reaction based on assay of telomeric repeat amplification protocol. Telomerase inhibitory samples were further tested for antiproliferation effects against the gastric cell line SNU-1 using the MTT method. Ethyl acetate extract of Pleurotus ostreatus, ethyl acetate and water extracts of Lasiosphaera fenzlii, hexane extract of Strobilomyces floccopus, water extract of Sarcodon aspratus, and hexane, ethyl acetate, and water extracts from Umbilicaria esculenta showed strong positive telomerase inhibitory activity. Hexane extract of S. floccopus and water extracts from the edible lichen U. esculenta exhibited strong anticancer effects against SNU-1 cells through antiproliferation assay. The water extract of U. esculenta has a great potential to be developed into an anticancer agent that targets telomerase.

  3. Cytochrome P450-inhibitory activity of parabens and phthalates used in consumer products.

    PubMed

    Ozaki, Hitomi; Sugihara, Kazumi; Watanabe, Yoko; Ohta, Shigeru; Kitamura, Shigeyuki

    2016-01-01

    The in vitro cytochrome P450 (CYP)-inhibitory effects of 11 parabens and 7 phthalates used in consumer products, as well as their hydrolytic metabolites, were investigated, using rat liver microsomes as an enzyme source. The effects on individual CYP isozymes were evaluated by assaying inhibition of activities towards specific substrates, i.e., ethoxyresorufin O-dealkylase (EROD), methoxyresorufin O-dealkylase (MROD), pentoxyresorufin O-dealkylase (PROD), 7-benzyloxy-4-trifluoromethylcoumarin dealkylase (BFCD), 7-methoxy-4-trifluoromethylcoumarin dealkylase (MFCD) and 7-ethoxy-4-trifluoromethylcoumarin dealkylase (EFCD) activities. These activities were dose-dependently inhibited, most potently by medium-side-chain parabens (C6-9) and phthalates (C4-6), and less potently by shorter- and longer-side-chain esters. The hydrolytic product of parabens, 4-hydroxybenzoic acid, was not inhibitory, while those of phthalates, phthalic acid monoesters, showed lower inhibitory activity than the parent phthalates. Parabens showed relatively potent inhibition of MFCD activity, considered to be mainly due to CYP2C, and phthalates showed relatively potent inhibition of PROD activity, considered to be mainly due to CYP2B. PMID:27432241

  4. Cytochrome P450-inhibitory activity of parabens and phthalates used in consumer products.

    PubMed

    Ozaki, Hitomi; Sugihara, Kazumi; Watanabe, Yoko; Ohta, Shigeru; Kitamura, Shigeyuki

    2016-01-01

    The in vitro cytochrome P450 (CYP)-inhibitory effects of 11 parabens and 7 phthalates used in consumer products, as well as their hydrolytic metabolites, were investigated, using rat liver microsomes as an enzyme source. The effects on individual CYP isozymes were evaluated by assaying inhibition of activities towards specific substrates, i.e., ethoxyresorufin O-dealkylase (EROD), methoxyresorufin O-dealkylase (MROD), pentoxyresorufin O-dealkylase (PROD), 7-benzyloxy-4-trifluoromethylcoumarin dealkylase (BFCD), 7-methoxy-4-trifluoromethylcoumarin dealkylase (MFCD) and 7-ethoxy-4-trifluoromethylcoumarin dealkylase (EFCD) activities. These activities were dose-dependently inhibited, most potently by medium-side-chain parabens (C6-9) and phthalates (C4-6), and less potently by shorter- and longer-side-chain esters. The hydrolytic product of parabens, 4-hydroxybenzoic acid, was not inhibitory, while those of phthalates, phthalic acid monoesters, showed lower inhibitory activity than the parent phthalates. Parabens showed relatively potent inhibition of MFCD activity, considered to be mainly due to CYP2C, and phthalates showed relatively potent inhibition of PROD activity, considered to be mainly due to CYP2B.

  5. Acute larvicidal activity against mosquitoes and oxygen consumption inhibitory activity of dihydroguaiaretic acid derivatives.

    PubMed

    Nishiwaki, Hisashi; Tabara, Yoshimi; Kishida, Taro; Nishi, Kosuke; Shuto, Yoshihiro; Sugahara, Takuya; Yamauchi, Satoshi

    2015-03-11

    (-)-Dihydroguaiaretic acid (DGA) and its derivatives having 3-hydroxyphenyl (3-OH-DGA) and variously substituted phenyl groups instead of 3-hydroxy-4-methoxyphenyl groups were synthesized to measure their larvicidal activity against the mosquito Culex pipiens Linnaeus, 1758 (Diptera: Culicidae). Compared with DGA and 3-OH-DGA (LC50 (M), 3.52 × 10(-5) and 4.57 × 10(-5), respectively), (8R,8'R)-lignan-3-ol (3) and its 3-Me (10), 2-OH (12), 3-OH (13), and 2-OMe (15) derivatives showed low potency (ca. 6-8 × 10(-5) M). The 4-Me derivative (11) showed the lowest potency (12.1 × 10(-5) M), and the 2-F derivative (4) showed the highest (2.01 × 10(-5) M). All of the synthesized compounds induced an acute toxic symptom against mosquito larvae, with potency varying with the type and position of the substituents. The 4-F derivative (6), which killed larvae almost completely within 45 min, suppressed the O2 consumption of the mitochondrial fraction, demonstrating that this compound inhibited mitochondrial O2 consumption contributing to a respiratory inhibitory activity.

  6. Activation of local inhibitory circuits in the dentate gyrus by adult-born neurons.

    PubMed

    Drew, Liam J; Kheirbek, Mazen A; Luna, Victor M; Denny, Christine A; Cloidt, Megan A; Wu, Melody V; Jain, Swati; Scharfman, Helen E; Hen, René

    2016-06-01

    Robust incorporation of new principal cells into pre-existing circuitry in the adult mammalian brain is unique to the hippocampal dentate gyrus (DG). We asked if adult-born granule cells (GCs) might act to regulate processing within the DG by modulating the substantially more abundant mature GCs. Optogenetic stimulation of a cohort of young adult-born GCs (0 to 7 weeks post-mitosis) revealed that these cells activate local GABAergic interneurons to evoke strong inhibitory input to mature GCs. Natural manipulation of neurogenesis by aging-to decrease it-and housing in an enriched environment-to increase it-strongly affected the levels of inhibition. We also demonstrated that elevating activity in adult-born GCs in awake behaving animals reduced the overall number of mature GCs activated by exploration. These data suggest that inhibitory modulation of mature GCs may be an important function of adult-born hippocampal neurons. © 2015 Wiley Periodicals, Inc.

  7. A cortico-hippocampal learning rule shapes inhibitory microcircuit activity to enhance hippocampal information flow

    PubMed Central

    Basu, Jayeeta; Srinivas, Kalyan V.; Cheung, Stephanie K.; Taniguchi, Hiroki; Huang, Z. Josh

    2013-01-01

    Summary How does coordinated activity between distinct brain regions implement a set of learning rules to sculpt information processing in a given neural circuit? Using interneuron cell-type specific optical activation and pharmacogenetic silencing in vitro, we show that temporally precise pairing of direct entorhinal perforant path (PP) and trisynaptic Schaffer collateral (SC) inputs to CA1 pyramidal cells selectively suppresses SC-associated perisomatic inhibition from cholecystokinin (CCK) expressing interneurons. The CCK interneurons provide a surprisingly strong feed-forward inhibitory drive to effectively control the coincident excitation of CA1 pyramidal neurons by convergent inputs. Thus, in-phase cortico-hippocampal activity provides a powerful heterosynaptic learning rule for long-term gating of information flow through the hippocampal excitatory macrocircuit by the silencing of the CCK inhibitory microcircuit. PMID:24050406

  8. Antimicrobial and quorum sensing inhibitory activities of the pericarp of Garcinia mangostana.

    PubMed

    Asfour, Hani Z

    2016-07-01

    A prenylated xanthone, α-mangostin was separated from the alcoholic extract of Garcinia mangostana pericarp. Its structure was established by different spectroscopic analysis. The total methanolic extract (TME) and different fractions of G. mangostana pericarp as well as α-mangostin were assessed for their antimicrobial and quorum sensing inhibitory effects (QSI). The TME, CHCl3 fraction, and α-mangostin exhibited strong activity against all tested strains. While, EtOAc, n-BuOH, and aqueous fractions showed moderate activity against some of the tested organisms. In addition TME, CHCl3, EtOAc, and α-mangostin showed promising QSI, while n-BuOH and aqueous fractions showed moderate activity. Minimal inhibitory concentration (MIC) for TME, CHCl3 fractions, and α-mangostin was also assessed. PMID:27592485

  9. Inhibitory effect of vanillin on cellulase activity in hydrolysis of cellulosic biomass.

    PubMed

    Li, Yun; Qi, Benkun; Wan, Yinhua

    2014-09-01

    Pretreatment of lignocellulosic material produces a wide variety of inhibitory compounds, which strongly inhibit the following enzymatic hydrolysis of cellulosic biomass. Vanillin is a kind of phenolics derived from degradation of lignin. The effect of vanillin on cellulase activity for the hydrolysis of cellulose was investigated in detail. The results clearly showed that vanillin can reversibly and non-competitively inhibit the cellulase activity at appropriate concentrations and the value of IC50 was estimated to be 30 g/L. The inhibition kinetics of cellulase by vanillin was studied using HCH-1 model and inhibition constants were determined. Moreover, investigation of three compounds with similar structure of vanillin on cellulase activity demonstrated that aldehyde group and phenolic hydroxyl groups of vanillin had inhibitory effect on cellulase. These results provide valuable and detailed information for understanding the inhibition of lignin derived phenolics on cellulase.

  10. Synthesis of some novel hydrazone and 2-pyrazoline derivatives: monoamine oxidase inhibitory activities and docking studies.

    PubMed

    Evranos-Aksöz, Begüm; Yabanoğlu-Çiftçi, Samiye; Uçar, Gülberk; Yelekçi, Kemal; Ertan, Rahmiye

    2014-08-01

    A novel series of 2-pyrazoline and hydrazone derivatives were synthesized and investigated for their human monoamine oxidase (hMAO) inhibitory activity. All compounds inhibited the hMAO isoforms (MAO-A or MAO-B) competitively and reversibly. With the exception of 5i, which was a selective MAO-B inhibitor, all derivatives inhibited hMAO-A potently and selectively. According to the experimental Ki values, compounds 6e and 6h exhibited the highest inhibitory activity towards the hMAO-A, whereas compound 5j, which carries a bromine atom at R(4) of the A ring of the pyrazoline, appeared to be the most selective MAO-A inhibitor. Tested compounds were docked computationally into the active site of the hMAO-A and hMAO-B isozymes. The computationally obtained results were in good agreement with the corresponding experimental values.

  11. Isolation and analysis of polysaccharide showing high hyaluronidase inhibitory activity in Nostochopsis lobatus MAC0804NAN.

    PubMed

    Yamaguchi, Yuji; Koketsu, Mamoru

    2016-03-01

    An active substance with high hyaluronidase inhibitory effect was isolated from the edible cyanobacterium Nostochopsis lobatus MAC0804NAN strain and characterized. The active component in the hot water extract was purified by anion exchange and gel filtration chromatography and was found to be a polysaccharide. The IC(50) against hyaluronidase of the purified polysaccharide was 7.18 μg/ml whose inhibitory activity is 14.5 times stronger than that of disodium cromoglycate (DSCG), an anti-allergy medication. The carbohydrate composition which was analyzed by GC-MS and NMR was found to be composed mainly of glucose, glucuronic acid, fucose, 2-O-methylfucose, mannose, galactose and xylose.

  12. Inhibitory compound of tyrosinase activity from the sprout of Polygonum hydropiper L. (Benitade).

    PubMed

    Miyazawa, Mitsuo; Tamura, Naotaka

    2007-03-01

    A tyrosinase inhibitor was isolated from the sprout of Polygonum hydropiper L. (Benitade) by activity-guided fractionation and identified as (2R,3R)-+-taxifolin (1) by spectroscopic means. Compound 1 inhibited 70% of tyrosinase activity at a concentration of 0.50 mM. ID50 (50% inhibition dose) value of compound 1 was 0.24 mM. As compared with tyrosinase inhibitor known cosmetic agent such as arbutin and kojic acid, compound 1 was more inhibited than the former and showed inhibitory effect equal to that of the latter. To study the inhibitory effect of (2R,3R)-+-taxifolin derivatives against tyrosinase activity, 3,7,3',4'-taxifolin tetraacetate (2) and 5,7,3',4'-taxifolin teramethyl ether (3) were also assayed together with compound 1.

  13. Evaluation of the effect of Thai breadfruit's heartwood extract on melanogenesis-inhibitory and antioxidation activities.

    PubMed

    Donsing, Piyaporn; Limpeanchob, Nanteetip; Viyoch, Jarupa

    2008-01-01

    The aim of this study was to clarify the melanogenesis-inhibitory and antioxidant activity of Thai breadfruit's heartwood extract for application as a skin-lightening agent. The heartwood of breadfruit (Artocarpus incisus ) grown in Phitsanulok Province, Thailand, was extracted by using diethyl ether or methanol. The amount of artocarpin, a major component of A. incisus extract, was determined by using the HPLC method. The artocarpin content found in ether extract was 45.19 +/- 0.45% w/w, whereas that in methanol extract was 19.61 +/- 0.05% w/w. The ether extract was then evaluated for tyrosinase-inhibitory, melanogenesis-inhibitory, and antioxidant activities. The tyrosinase-inhibitory activity was tested in vitro by monitoring the inhibition of the extract against the formation of DOPAchrome by tyrosinase enzyme. The results showed that the tyrosinase-inhibitory activity of the extract was in a dose-dependent manner. The obtained IC50 value was 10.26 +/- 3.04 microg/ml, while kojic acid, a well-known tyrosinase inhibitor, provided an IC50 of 7.89 +/- 0.18 microg/ml. Melanocyte B16F1 melanoma cells (ATCC No. CRL-6323) were then used for determination of the melanogenesis-inhibitory activity of the extract, comparing it to hydroquinone, kojic acid, and purified artocarpin. The amount of melanin produced by the cells was monitored by measuring an absorbence at 490 nm. The obtained results indicated that A. incisus extract at a concentration of 2 to 25 microg/ml was able to decrease the melanin production of the melanocyte B16F1 cells. The obtained micrograph also confirmed that the extract did not change the cell morphology but reduced the melanin content by inhibiting melanin synthesis, whereas the purified artocarpin at a concentration of 4.5 microg/ml caused changes in cell morphology. Additionally, the extract exhibited antioxidant activity in a dose-dependent manner at an EC50 of 169.53 +/- 9.73 microg/ml, according to DPPH assay. The obtained results indicated

  14. Antioxidant and lipase inhibitory activities and essential oil composition of pomegranate peel extracts.

    PubMed

    Hadrich, Fatma; Cher, Slim; Gargouri, Youssef Talel; Adel, Sayari

    2014-01-01

    The chemical composition of essential oil, antioxidant and pancreatic lipase inhibitory activities of various solvent extracts obtained from pomegranate peelTunisian cultivar was evaluated. Gas chromatography/mass spectrometry was used to determine the composition of the PP essential oil. Nine-teen components were identified and the main compounds were the camphor (60.32%) and the benzaldehyde (20.98%). The phenolic and flavonoids content varied from 0 to 290.10 mg Gallic acid equivalent and from 5.2 to 20.43 mg catechin equivalent/g dried extract. The antioxidant activity of various solvent extracts from pomegranate peel was also investigated using various in vitro assays as the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical method, β-carotene bleaching and reducing power assays.Methanol and ethanol extracts showed the most potent antioxidant activity in all assays tested followed by water and acetone extracts. The inhibitory effect of the pomegranate peelextracts on porcine pancreatic lipase was evaluated and the results showed that ethanol and methanol extracts markedly reduced lipase activity. Generally, the highestlipase activity inhibitory (100%) was observed at a concentration of 1 mg/ml after 30 min of incubation. LC-MS analysis of ethanol extract showed the presence of four components which are cholorogenic acid, mannogalloylhexoside, gallic acid and ellagic acid. Our findings demonstrate that the ethanol extract from pomegranate peel might be a good candidate for furtherinvestigations of new bioactive substances. PMID:24770478

  15. Inhibitory activity in vitro of probiotic lactobacilli against oral Candida under different fermentation conditions.

    PubMed

    Jiang, Q; Stamatova, I; Kari, K; Meurman, J H

    2015-01-01

    Clinical studies have shown that probiotics positively affect oral health by decreasing gum bleeding and/or reducing salivary counts of certain oral pathogens. Our aim was to investigate the inhibitory effect of six probiotic lactobacilli against opportunistic oral Candida species. Sugar utilisation by both lactobacilli and Candida was also assessed. Agar overlay assay was utilised to study growth inhibition of Candida albicans, Candida glabrata and Candida krusei by Lactobacillus rhamnosus GG, Lactobacillus casei Shirota, Lactobacillus reuteri SD2112, Lactobacillus brevis CD2, Lactobacillus bulgaricus LB86 and L. bulgaricus LB Lact. The inhibitory effect was measured at pH 5.5, 6.4, and 7.2, respectively, and in the presence of five different carbohydrates in growth medium (glucose, fructose, lactose, sucrose, and sorbitol). Growth and final pH values were measured at two-hour time points to 24 h. L. rhamnosus GG showed the strongest inhibitory activity in fructose and glucose medium against C. albicans, followed by L. casei Shirota, L. reuteri SD2112 and L. brevis CD2. None of the lactobacilli tested affected the growth of C. krusei. Only L. rhamnosus GG produced slight inhibitory effect on C. glabrata. The lower pH values led to larger inhibition zones. Sugar fermentation profiles varied between the strains. L. casei Shirota grew in the presence of all sugars tested, whereas L. brevis CD2 could utilise only glucose and fructose. All Candida species metabolised the available sugars but the most rapid growth was observed with C. glabrata. The results suggest that commercially available probiotics differ in their inhibitory activity and carbohydrate utilisation; the above properties are modified by different pH values and sugars with more pronounced inhibition at lower pH.

  16. Susceptibility of enterococci. I. Inhibitory and bactericidal activity of several chemoantibiotics against Streptococcus faecalis and Streptococcus faecium.

    PubMed

    Fabbri, A; Manno, G; Tacchella, A; Belli, M L; Palmero, C

    1986-10-01

    The authors present a microbiological study of 100 strains of Enterococcus (70 strains of Streptococcus faecalis and 30 strains of Streptococcus faecium) tested for susceptibility to the following antibiotics, amoxicillin, ampicillin + flucloxacillin, piperacillin, rifampicin, vancomycin, netilmicin, ofloxacin, and norfloxacin. The assessment of minimum inhibitory and minimum bactericidal concentrations of these substances indicates that all have good inhibitory activity except netilmicin, which is active at higher concentrations; with rifampicin and vancomycin showing very poor bactericidal activity. The bactericidal activity of penicillins was hard to assess because of tolerance and paradoxical effect phenomena. The quinolones showed good inhibitory and bactericidal activity.

  17. Effects of incentives, age, and behavior on brain activation during inhibitory control: a longitudinal fMRI study.

    PubMed

    Paulsen, David J; Hallquist, Michael N; Geier, Charles F; Luna, Beatriz

    2015-02-01

    We investigated changes in brain function supporting inhibitory control under age-controlled incentivized conditions, separating age- and performance-related activation in an accelerated longitudinal design including 10- to 22-year-olds. Better inhibitory control correlated with striatal activation during neutral trials, while Age X Behavior interactions in the striatum indicated that in the absence of extrinsic incentives, younger subjects with greater reward circuitry activation successfully engage in greater inhibitory control. Age was negatively correlated with ventral amygdala activation during Loss trials, suggesting that amygdala function more strongly mediates bottom-up processing earlier in development when controlling the negative aspects of incentives to support inhibitory control. Together, these results indicate that with development, reward-modulated cognitive control may be supported by incentive processing transitions in the amygdala, and from facilitative to obstructive striatal function during inhibitory control. PMID:25284272

  18. Effects of incentives, age, and behavior on brain activation during inhibitory control: A longitudinal fMRI study

    PubMed Central

    Paulsen, David J.; Hallquist, Michael N.; Geier, Charles F.; Luna, Beatriz

    2014-01-01

    We investigated changes in brain function supporting inhibitory control under age-controlled incentivized conditions, separating age- and performance-related activation in an accelerated longitudinal design including 10- to 22-year-olds. Better inhibitory control correlated with striatal activation during neutral trials, while Age × Behavior interactions in the striatum indicated that in the absence of extrinsic incentives, younger subjects with greater reward circuitry activation successfully engage in greater inhibitory control. Age was negatively correlated with ventral amygdala activation during Loss trials, suggesting that amygdala function more strongly mediates bottom-up processing earlier in development when controlling the negative aspects of incentives to support inhibitory control. Together, these results indicate that with development, reward-modulated cognitive control may be supported by incentive processing transitions in the amygdala, and from facilitative to obstructive striatal function during inhibitory control. PMID:25284272

  19. Discovery, structure-activity relationship study, and oral analgesic efficacy of cyproheptadine derivatives possessing N-type calcium channel inhibitory activity.

    PubMed

    Yamamoto, Takashi; Niwa, Seiji; Iwayama, Satoshi; Koganei, Hajime; Fujita, Shin-ichi; Takeda, Tomoko; Kito, Morikazu; Ono, Yukitsugu; Saitou, Yuki; Takahara, Akira; Iwata, Seinosuke; Yamamoto, Hiroshi; Shoji, Masataka

    2006-08-01

    Antiallergic drug cyproheptadine (Cyp) is known to have inhibitory activities for L-type calcium channels in addition to histamine and serotonin receptors. Since we found that Cyp had an inhibitory activity against N-type calcium channel, Cyp was optimized to obtain more selective N-type calcium channel blocker with analgesic action. As a consequence of the optimization, we found 13 with potent N-type calcium channel inhibitory activity which had lower inhibitory activities against L-type calcium channel, histamine (H1), and serotonin (5-HT2A) receptors than those of Cyp. 13 showed an oral analgesic activity in rat formalin-induced pain model.

  20. Antioxidant and enzyme inhibitory activities of Plebeian herba (Salvia plebeia R. Br.) under different cultivation conditions.

    PubMed

    Chen, Lei; Kang, Young-Hwa

    2014-03-12

    An adaptation of cultural management to the specific cultural system, as well as crop demand, can further result in the improvement of the quality of horticultural products. Therefore, this study focused on the antioxidant and enzyme inhibitory activities of Plebeian herba (Salvia plebeia R. Br.) grown in hydroponics in comparison with those of the plant grown in soil. The antioxidant activities of Plebeian herba extract were measured as 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging abilities as well as the reducing power by decreasing nitric oxide (NO) and superoxide dismutase activity (SOD) in vitro. Interestingly, by comparison with hydroponics and traditional cultivation, Plebeian herba cultivated in nutrition-based soil improved inhibitory effect on free radicals of DPPH, ABTS, and NO and increased the contents of phenolics such as caffeic acid (1), luteolin-7-glucoside (2), homoplantaginin (3), hispidulin (4), and eupatorin. Free radical scavenging and SOD activity, as well as α-glucosidase inhibitory effect, were higher in Plebeian herba grown in nutrition-based soil than in plants grown in hydroponics and traditional condition. PMID:24422962

  1. Sequential injection spectrophotometric system for evaluation of mushroom tyrosinase-inhibitory activity.

    PubMed

    Moonrungsee, Nuntaporn; Shimamura, Tomoko; Kashiwagi, Takehiro; Jakmunee, Jaroon; Higuchi, Keiro; Ukeda, Hiroyuki

    2012-11-15

    A sequential injection (SI) spectrophotometric method with absorbance detection at 475 nm has been developed for evaluating activity of some compounds on an inhibition of the mushroom tyrosinase. The method involved a reaction of 3,4-dihydroxyphenylalanine (L-DOPA) and mushroom tyrosinase to form the o-dopaquinone. The decrease of the o-dopaquinone was related to an increase of tyrosinase-inhibitory activity. Under the optimum conditions (concentration and volume of L-DOPA and mushroom tyrosinase of 2.0 mM, 60 μL and 142 U mL(-1), 15 μL, respectively), some antioxidant compounds were examined for the tyrosinase-inhibitory activity. A batch enzymatic assay of tyrosinase-inhibitory activity was applied as the reference method for comparison. The results of IC(50) values obtained from the proposed method and the batch method were correlated well, with r(2) of 0.969. The SIA provides higher precision and degrees of automation, consumes smaller amounts of chemicals and it is simpler and faster than the batch method.

  2. Antioxidant and enzyme inhibitory activities of Plebeian herba (Salvia plebeia R. Br.) under different cultivation conditions.

    PubMed

    Chen, Lei; Kang, Young-Hwa

    2014-03-12

    An adaptation of cultural management to the specific cultural system, as well as crop demand, can further result in the improvement of the quality of horticultural products. Therefore, this study focused on the antioxidant and enzyme inhibitory activities of Plebeian herba (Salvia plebeia R. Br.) grown in hydroponics in comparison with those of the plant grown in soil. The antioxidant activities of Plebeian herba extract were measured as 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging abilities as well as the reducing power by decreasing nitric oxide (NO) and superoxide dismutase activity (SOD) in vitro. Interestingly, by comparison with hydroponics and traditional cultivation, Plebeian herba cultivated in nutrition-based soil improved inhibitory effect on free radicals of DPPH, ABTS, and NO and increased the contents of phenolics such as caffeic acid (1), luteolin-7-glucoside (2), homoplantaginin (3), hispidulin (4), and eupatorin. Free radical scavenging and SOD activity, as well as α-glucosidase inhibitory effect, were higher in Plebeian herba grown in nutrition-based soil than in plants grown in hydroponics and traditional condition.

  3. Antioxidant, Iron Chelating and Tyrosinase Inhibitory Activities of Extracts from Talinum triangulare Leach Stem

    PubMed Central

    Oliveira Amorim, Ana Paula; Campos de Oliveira, Márcia Cristina; de Azevedo Amorim, Thiago; Echevarria, Aurea

    2013-01-01

    The aim of this work is to evaluate the antioxidant activity against the radical species DPPH, the reducing capacity against Fe II ions, and the inhibitory activity on the tyrosinase enzyme of the T. triangulare. Hydromethanolic crude extract provided two fractions after the liquid/liquid partition with chloroform. The Folin-Ciocalteu method determined the total phenolic content of the crude extract (CE) and the hydromethanolic fraction (Fraction 1), resulting in a concentration of 0.5853 g/100 g for Fraction 1, and 0.1400 g/100 g for the CE. Taking into account the results of the DPPH, the free radical scavenging capacity was confirmed. The formation of complexes with Fe II ions was evaluated by UV/visible spectrometry; results showed that CE has complexing power similar to the positive control (Gingko biloba extract).The inhibitory capacity of samples against the tyrosinase enzyme was determined by the oxidation of L-DOPA, providing IC50 values of 13.3 μg·mL−1 (CE) and 6.6 μg·mL−1 (Fraction 1). The values indicate that Fraction 1 was more active and showed a higher inhibitory power on the tyrosinase enzyme than the ascorbic acid, used as positive control. The hydromethanolic extract of T. triangulare proved to have powerful antioxidant activity and to inhibit the tyrosinase enzyme; its potential is increased after the partition with chloroform. PMID:26784338

  4. Galantamine derivatives with indole moiety: Docking, design, synthesis and acetylcholinesterase inhibitory activity.

    PubMed

    Atanasova, Mariyana; Stavrakov, Georgi; Philipova, Irena; Zheleva, Dimitrina; Yordanov, Nikola; Doytchinova, Irini

    2015-09-01

    The inhibitors of acetylcholinesterase are the main therapy against Alzheimer's disease. Among them, galantamine is the best tolerated and the most prescribed drug. In the present study, 41 galantamine derivatives with known acetylcholinesterase inhibitory activities expressed as IC50 were selected from the literature and docked into a recombinant human acetylcholinesterase by GOLD. A linear relationship between GoldScores and pIC50 values was found and used to design and predict novel galantamine derivatives with indole moiety in the side chain. The four best predicted compounds were synthesized and tested for inhibitory activity. All of them were between 11 and 95 times more active than galantamine. The novel galantamine derivatives with indole moiety have dual site binding to the enzyme--the galantamine moiety binds to the catalytic anionic site and the indole moiety binds to peripheral anionic site. Additionally, the indole moiety of one of the novel inhibitors binds in a region, close to the peripheral anionic site of the enzyme, where the Ω-loop of amyloid beta peptide adheres to acetylcholinesterase. This compound emerges as a promising lead compound for multi-target anti-Alzheimer therapy not only because of the strong inhibitory activity, but also because it is able to block the amyloid beta deposition on acetylcholinesterase. PMID:26260334

  5. FKBP-12 exhibits an inhibitory activity on calcium oxalate crystal growth in vitro.

    PubMed Central

    Han, In Sook; Nakagawa, Yasushi; Park, Jong Wook; Suh, Min Ho; Suh, Sung Il; Shin, Song Woo; Ahn, Su Yul; Choe, Byung Kil

    2002-01-01

    Urolithiasis and calcium oxalate crystal deposition diseases are still significant medical problems. In the course of nephrocalcin cDNA cloning, we have identified FKBP-12 as an inhibitory molecule of calcium oxalate crystal growth. lambdagt 11 cDNA libraries were constructed from renal carcinoma tissues and screened for nephrocalcin cDNA clones using anti-nephrocalcin antibody as a probe. Clones expressing recombinant proteins, which appeared to be antigenically cross-reactive to nephrocalcin, were isolated and their DNA sequences and inhibitory activities on the calcium oxalate crystal growth were determined. One of the clone lambda gt 11 #31-1 had a partial fragment (80 bp) of FKBP-12 cDNA as an insert. Therefore, a full-length FKBP-12 cDNA was PCR-cloned from the lambda gt 11 renal carcinoma cDNA library and was subcloned into an expression vector. The resultant recombinant FKBP-12 exhibited an inhibitory activity on the calcium oxalate crystal growth (Kd=10(-7) M). Physiological effect of the extracellular FKBP-12 was investigated in terms of macrophage activation and proinflammatory cytokine gene induction. Extracellular FKBP-12 failed to activate macrophages even at high concentrations. FKBP-12 seems an anti-stone molecule for the oxalate crystal deposition disease and recurrent stone diseases. PMID:11850587

  6. Melanogenesis inhibitory activity of two generic drugs: cinnarizine and trazodone in mouse B16 melanoma cells.

    PubMed

    Chang, Te-Sheng; Lin, Victor Chia-Hsiang

    2011-01-01

    More than 200 generic drugs were screened to identify the inhibitory activity on melanogenesis in mouse B16 melanoma cells. Cinnarizine and trazodone were identified as melanogenesis inhibitors. The inhibitory effects of the two drugs on cell survival, melanogenesis, and tyrosinase activity were investigated. The results showed that both cinnarizine and trazodone inhibited melanogenesis in B16 cells by a dose-dependent manner at the non-cytotoxic concentrations. Based on the results of the present study, seeking new melanogenesis inhibitors from generic drugs is an alternative approach to developing new depigmenting agents in cosmeceuticals. Moreover, cinnarizine and trazodone were proven to be good candidates as skin-whitening agents for treatment of skin hyperpigmentation. PMID:22272104

  7. Melanogenesis Inhibitory Activity of Two Generic Drugs: Cinnarizine and Trazodone in Mouse B16 Melanoma Cells

    PubMed Central

    Chang, Te-Sheng; Lin, Victor Chia-Hsiang

    2011-01-01

    More than 200 generic drugs were screened to identify the inhibitory activity on melanogenesis in mouse B16 melanoma cells. Cinnarizine and trazodone were identified as melanogenesis inhibitors. The inhibitory effects of the two drugs on cell survival, melanogenesis, and tyrosinase activity were investigated. The results showed that both cinnarizine and trazodone inhibited melanogenesis in B16 cells by a dose-dependent manner at the non-cytotoxic concentrations. Based on the results of the present study, seeking new melanogenesis inhibitors from generic drugs is an alternative approach to developing new depigmenting agents in cosmeceuticals. Moreover, cinnarizine and trazodone were proven to be good candidates as skin-whitening agents for treatment of skin hyperpigmentation. PMID:22272104

  8. Jojoba seed meal proteins associated with proteolytic and protease inhibitory activities.

    PubMed

    Shrestha, Madan K; Peri, Irena; Smirnoff, Patricia; Birk, Yehudith; Golan-Goldhirsh, Avi

    2002-09-25

    The jojoba, Simmondsia chinensis, is a characteristic desert plant native to the Sonoran desert. The jojoba meal after oil extraction is rich in protein. The major jojoba proteins were albumins (79%) and globulins (21%), which have similar amino acid compositions and also showed a labile thrombin-inhibitory activity. SDS-PAGE showed two major proteins at 50 kDa and 25 kDa both in the albumins and in the globulins. The 25 kDa protein has trypsin- and chymotrypsin-inhibitory activities. In vitro digestibility of the globulins and albumins resembled that of casein and soybean protein concentrates and was increased after heat treatment. The increased digestibility achieved by boiling may be attributed to inactivation of the protease inhibitors and denaturation of proteins.

  9. Predicting the DPP-IV inhibitory activity pIC₅₀ based on their physicochemical properties.

    PubMed

    Gu, Tianhong; Yang, Xiaoyan; Li, Minjie; Wu, Milin; Su, Qiang; Lu, Wencong; Zhang, Yuhui

    2013-01-01

    The second development program developed in this work was introduced to obtain physicochemical properties of DPP-IV inhibitors. Based on the computation of molecular descriptors, a two-stage feature selection method called mRMR-BFS (minimum redundancy maximum relevance-backward feature selection) was adopted. Then, the support vector regression (SVR) was used in the establishment of the model to map DPP-IV inhibitors to their corresponding inhibitory activity possible. The squared correlation coefficient for the training set of LOOCV and the test set are 0.815 and 0.884, respectively. An online server for predicting inhibitory activity pIC50 of the DPP-IV inhibitors as described in this paper has been given in the introduction.

  10. Structure activity relationship modelling of milk protein-derived peptides with dipeptidyl peptidase IV (DPP-IV) inhibitory activity.

    PubMed

    Nongonierma, Alice B; FitzGerald, Richard J

    2016-05-01

    Quantitative structure activity type models were developed in an attempt to predict the key features of peptide sequences having dipeptidyl peptidase IV (DPP-IV) inhibitory activity. The models were then employed to help predict the potential of peptides, which are currently reported in the literature to be present in the intestinal tract of humans following milk/dairy product ingestion, to act as inhibitors of DPP-IV. Two models (z- and v-scale) for short (2-5 amino acid residues) bovine milk peptides, behaving as competitive inhibitors of DPP-IV, were developed. The z- and the v-scale models (p<0.05, R(2) of 0.829 and 0.815, respectively) were then applied to 56 milk protein-derived peptides previously reported in the literature to be found in the intestinal tract of humans which possessed a structural feature of DPP-IV inhibitory peptides (P at the N2 position). Ten of these peptides were synthetized and tested for their in vitro DPP-IV inhibitory properties. There was no agreement between the predicted and experimentally determined DPP-IV half maximal inhibitory concentrations (IC50) for the competitive peptide inhibitors. However, the ranking for DPP-IV inhibitory potency of the competitive peptide inhibitors was conserved. Furthermore, potent in vitro DPP-IV inhibitory activity was observed with two peptides, LPVPQ (IC50=43.8±8.8μM) and IPM (IC50=69.5±8.7μM). Peptides present within the gastrointestinal tract of human may have promise for the development of natural DPP-IV inhibitors for the management of serum glucose.

  11. Antioxidative and melanogenesis-inhibitory activities of caffeoylquinic acids and other compounds from moxa.

    PubMed

    Akihisa, Toshihiro; Kawashima, Kohta; Orido, Masashi; Akazawa, Hiroyuki; Matsumoto, Masahiro; Yamamoto, Ayako; Ogihara, Eri; Fukatsu, Makoto; Tokuda, Harukuni; Fuji, Jizaemon

    2013-03-01

    The MeOH extract of moxa, the processed leaves of Artemisia princeps PAMP. (Asteraceae), exhibited potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and melanogenesis-inhibitory activity in α-melanocyte-stimulating hormone (α-MSH)-stimulated B16 melanoma cells. Eight caffeoylquinic acids, 1 and 6-12, five flavonoids, 13-17, two benzoic acid derivatives, 18 and 19, three coumarin derivatives, 20-22, four steroids, 23-26, and six triterpenoids, 27-32, were isolated from the MeOH extract. Upon evaluation of compounds 1, 6-23, and four semisynthetic caffeoylquinic acid esters, 2-5, for their DPPH radical-scavenging activity, 15 compounds, 1-13, 17, and 19, showed potent activities (IC(50) 3.1-16.8 μM). The 15 compounds exhibited, moreover, potent inhibitory activities (51.1-92.5% inhibition) against peroxidation of linoleic acid emulsion at 10 μg/ml concentration. In addition, when 27 compounds, 1-8, 10, 12, 13, 15-18, 20-25, and 27-32, were evaluated for their inhibitory activity against melanogenesis in α-MSH-stimulated B16 melanoma cells, five caffeoylquinic acids, i.e., chlorogenic acid (1), ethyl chlorogenate (3), propyl chlorogenate (4), isopropyl chlorogenate (5), and butyl chlorogenate (6), along with homoorientin (17) and vanillic acid (18), exhibited inhibitory activities with 33-62% reduction of melanin content at 100 μM concentration with no or almost no toxicity to the cells (89-114% of cell viability at 100 μM). Western blot analysis showed that compound 6 reduced the protein levels of microphtalmia-associated transcription factor (MITF), tyrosinase, tyrosine-related protein 1 (TRP-1), and TRP-2 mostly in a concentration-dependent manner, suggesting that this compound inhibits melanogenesis on α-MSH-stimulated B16 melanoma cells by, at least in part, inhibiting the expression of MITF, followed by decreasing the expression of tyrosinase, TRP-1, and TRP-2. Furthermore, four compounds, 13, 15, 16, and 30, exhibited

  12. Bioactive Compounds, Antioxidant, Xanthine Oxidase Inhibitory, Tyrosinase Inhibitory and Anti-Inflammatory Activities of Selected Agro-Industrial By-products

    PubMed Central

    Oskoueian, Ehsan; Abdullah, Norhani; Hendra, Rudi; Karimi, Ehsan

    2011-01-01

    Evaluation of abundantly available agro-industrial by-products for their bioactive compounds and biological activities is beneficial in particular for the food and pharmaceutical industries. In this study, rapeseed meal, cottonseed meal and soybean meal were investigated for the presence of bioactive compounds and antioxidant, anti-inflammatory, xanthine oxidase and tyrosinase inhibitory activities. Methanolic extracts of rapeseed meal showed significantly (P < 0.01) higher phenolics and flavonoids contents; and significantly (P < 0.01) higher DPPH and nitric oxide free radical scavenging activities when compared to that of cottonseed meal and soybean meal extracts. Ferric thiocyanate and thiobarbituric acid tests results showed rapeseed meal with the highest antioxidant activity (P < 0.01) followed by BHT, cotton seed meal and soybean meal. Rapeseed meal extract in xanthine oxidase and tyrosinase inhibitory assays showed the lowest IC50 values followed by cottonseed and soybean meals. Anti-inflammatory assay using IFN-γ/LPS stimulated RAW 264.7 cells indicated rapeseed meal is a potent source of anti-inflammatory agent. Correlation analysis showed that phenolics and flavonoids were highly correlated to both antioxidant and anti-inflammatory activities. Rapeseed meal was found to be promising as a natural source of bioactive compounds with high antioxidant, anti-inflammatory, xanthine oxidase and tyrosinase inhibitory activities in contrast to cotton and soybean meals. PMID:22272095

  13. Evaluation of Xanthine Oxidase Inhibitory Potential and In vivo Hypouricemic Activity of Dimocarpus longan Lour. Extracts

    PubMed Central

    Sheu, Shi-Yuan; Fu, Yuan-Tsung; Huang, Wen-Dar; Chen, Yung-Ann; Lei, Yi-Chih; Yao, Chun-Hsu; Hsu, Feng-Lin; Kuo, Tzong-Fu

    2016-01-01

    Background: Longan is a fruit tree known to contain many phenolic components, which are capable of protecting people from oxidative damage through an anti-inflammatory mechanism. It may be also worthwhile to study the effect on lowering uric acid activity. Materials and Methods: This study investigates the lowering of uric acid using longan extracts, including flowers, pericarps, seeds, leaves, and twigs, on potassium-oxonate-induced hyperuricemia mice and its inhibitory actions against xanthine oxidase (XO) activities. Results: The findings revealed that ethyl acetate fraction of longan extracts exhibited strong XO-inhibitory activity, and the flower extracts (IC50 = 115.8 μg/mL) revealed more potent XO-inhibitory activity to those of pericarps (118.9 μg/mL), twigs (125.3 μg/mL), seeds (262.5 μg/mL), and leaves (331.1 μg/mL) in vitro. In addition, different dosages of longan extract (50–100 mg/kg) were administered to hyperuricemic mice. The lowering effect of longan extracts on uric acid at 75 mg/kg markedly reduced plasma uric acid levels in decreasing order: Flowers (80%) > seeds (72%) > pericarps (64%) > twigs (59%) > leaves (41%), compared with allopurinol (89%). Finally, 10 isolated phytochemicals from longan flowers were then examined in vitro. The results indicated that proanthocyanidin A2 and acetonylgeraniin A significantly inhibited XO activity in vitro. This is the first report providing new insights into the urate-reducing effect of phenolic dimer and hydrolyzable tannin, which can be developed to potential hypouricemic agents. SUMMARY Longan flower extracts possess more potent XO-inhibitory activity than pericarps, twigs, seeds, and leaves in vitroThe lowering effect of longan flowers and seeds extracts markedly reduced plasma uric acid levels as compared to allopurinol in vivoThe extract proanthocyanidin A2 and acetonylgeraniin A were demonstrated potent XO inhibitory activity in vitro Abbreviations used: PO: Potassium-oxonate, XO: xanthine

  14. Microwave assisted synthesis, cholinesterase enzymes inhibitory activities and molecular docking studies of new pyridopyrimidine derivatives.

    PubMed

    Basiri, Alireza; Murugaiyah, Vikneswaran; Osman, Hasnah; Kumar, Raju Suresh; Kia, Yalda; Ali, Mohamed Ashraf

    2013-06-01

    A series of hitherto unreported pyrido-pyrimidine-2-ones/pyrimidine-2-thiones were synthesized under microwave assisted solvent free reaction conditions in excellent yields and evaluated in vitro for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes inhibitory activity. Among the pyridopyrimidine derivatives, 7e and 7l displayed 2.5- and 1.5-fold higher enzyme inhibitory activities against AChE as compared to standard drug, galanthamine, with IC50 of 0.80 and 1.37 μM, respectively. Interestingly, all the compounds except 6k, 7j and 7k displayed higher inhibitory potential against BChE enzyme in comparison to standard with IC50 ranging from 1.18 to 18.90 μM. Molecular modeling simulations of 7e and 7l was performed using three-dimensional structure of Torpedo californica AChE (TcAChE) and human butyrylcholinesterase (hBChE) enzymes to disclose binding interaction and orientation of these molecule into the active site gorge of respective receptors.

  15. Hypotensive and Angiotensin-Converting Enzyme Inhibitory Activities of Eisenia fetida Extract in Spontaneously Hypertensive Rats

    PubMed Central

    Mao, Shumei; Li, Chengde

    2015-01-01

    Objectives. This study aimed to investigate the antihypertensive effects of an Eisenia fetida extract (EFE) and its possible mechanisms in spontaneously hypertensive rats (SHR rats). Methods. Sixteen-week-old SHR rats and Wistar-Kyoto rats (WKY rats) were used in this study. Rats were, respectively, given EFE (EFE group), captopril (captopril group), or phosphate-buffered saline (PBS) (normal control group and SHR group) for 4 weeks. ACE inhibitory activity of EFE in vitro was determined. The systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using a Rat Tail-Cuff Blood Pressure System. Levels of angiotensin II (Ang II), aldosterone (Ald), and 6-keto-prostaglandin F1 alpha (6-keto-PGF1α) in plasma were determined by radioimmunoassay, and serum nitric oxide (NO) concentration was measured by Griess reagent systems. Results. EFE had marked ACE inhibitory activity in vitro (IC50 = 2.5 mg/mL). After the 4-week drug management, SHR rats in EFE group and in captopril group had lower SBP and DBP, lower levels of Ang II and Ald, and higher levels of 6-keto-PGF1α and NO than the SHR rats in SHR group. Conclusion. These results indicate that EFE has hypotensive effects in SHR rats and its effects might be associated with its ACE inhibitory activity. PMID:26798397

  16. Medicinal Plants and Their Inhibitory Activities against Pancreatic Lipase: A Review.

    PubMed

    Seyedan, Atefehalsadat; Alshawsh, Mohammed Abdullah; Alshagga, Mustafa Ahmed; Koosha, Sanaz; Mohamed, Zahurin

    2015-01-01

    Obesity is recognized as a major life style disorder especially in developing countries and it is prevailing at an alarming speed in new world countries due to fast food intake, industrialization, and reduction of physical activity. Furthermore, it is associated with a vast number of chronic diseases and disabilities. To date, relatively effective drugs, from either natural or synthetic sources, are generally associated with serious side effects, often leading to cessation of clinical trials or even withdrawal from the market. In order to find new compounds which are more effective or with less adverse effects compared to orlistat, the drug that has been approved for obesity, new compounds isolated from natural products are being identified and screened for antiobesity effects, in particular, for their pancreatic lipase inhibitory effect. Pancreatic lipase inhibitory activity has been extensively used for the determination of potential efficacy of natural products as antiobesity agents. In attempts to identify natural products for overcoming obesity, more researches have been focused on the identification of newer pancreatic lipase inhibitors with less unpleasant adverse effects. In this review, we consider the potential role of plants that have been investigated for their pancreatic lipase inhibitory activity.

  17. Synthesis and in vitro α-chymotrypsin inhibitory activity of 6-chlorobenzimidazole derivatives.

    PubMed

    Siddiqui, Hina; Farooq, Rabia; Marasini, Bishnu P; Malik, Rizwana; Syed, Naima; Moin, Syed Tarique; Atta-Ur-Rahman; Choudhary, M Iqbal

    2016-08-15

    A library of benzimidazole derivatives 1-20 were synthesized, and studied for their α-chymotrypsin (α-CT) inhibitory activity in vitro. Kinetics and molecular docking studies were performed to identify the type of inhibition. Compound 1 was found to be a good inhibitor of α-chymotrypsin enzyme (IC50=14.8±0.1μM, Ki=16.4μM), when compared with standard chymostatin (IC50=5.7±0.13μM). Compounds 2-8, 15, 17, and 18 showed significant inhibitory activities. All the inhibitors were found to be competitive inhibitors, except compound 17, which was a mixed type inhibitor. The substituents (R) in para and ortho positions of phenyl ring B, apparently played a key role in the inhibitory potential of the series. Compounds 1-20 were also studied for their cytotoxicity profile by using 3T3 mouse fibroblast cells and compounds 3, 5, 6, 8, 12-14, 16, 17, 19, and 20 were found to be cytotoxic. Molecular docking was performed on the most active members of the series in comparison to the standard compound, chymostatin, to identify the most likely binding modes. The compounds reported here can serve as templates for further studies for new inhibitors of α-chymotrypsin and other chymotrypsin-like serine proteases enzymes. PMID:27374882

  18. Medicinal Plants and Their Inhibitory Activities against Pancreatic Lipase: A Review

    PubMed Central

    Seyedan, Atefehalsadat; Alshawsh, Mohammed Abdullah; Alshagga, Mustafa Ahmed; Koosha, Sanaz; Mohamed, Zahurin

    2015-01-01

    Obesity is recognized as a major life style disorder especially in developing countries and it is prevailing at an alarming speed in new world countries due to fast food intake, industrialization, and reduction of physical activity. Furthermore, it is associated with a vast number of chronic diseases and disabilities. To date, relatively effective drugs, from either natural or synthetic sources, are generally associated with serious side effects, often leading to cessation of clinical trials or even withdrawal from the market. In order to find new compounds which are more effective or with less adverse effects compared to orlistat, the drug that has been approved for obesity, new compounds isolated from natural products are being identified and screened for antiobesity effects, in particular, for their pancreatic lipase inhibitory effect. Pancreatic lipase inhibitory activity has been extensively used for the determination of potential efficacy of natural products as antiobesity agents. In attempts to identify natural products for overcoming obesity, more researches have been focused on the identification of newer pancreatic lipase inhibitors with less unpleasant adverse effects. In this review, we consider the potential role of plants that have been investigated for their pancreatic lipase inhibitory activity. PMID:26640503

  19. Medicinal Plants and Their Inhibitory Activities against Pancreatic Lipase: A Review.

    PubMed

    Seyedan, Atefehalsadat; Alshawsh, Mohammed Abdullah; Alshagga, Mustafa Ahmed; Koosha, Sanaz; Mohamed, Zahurin

    2015-01-01

    Obesity is recognized as a major life style disorder especially in developing countries and it is prevailing at an alarming speed in new world countries due to fast food intake, industrialization, and reduction of physical activity. Furthermore, it is associated with a vast number of chronic diseases and disabilities. To date, relatively effective drugs, from either natural or synthetic sources, are generally associated with serious side effects, often leading to cessation of clinical trials or even withdrawal from the market. In order to find new compounds which are more effective or with less adverse effects compared to orlistat, the drug that has been approved for obesity, new compounds isolated from natural products are being identified and screened for antiobesity effects, in particular, for their pancreatic lipase inhibitory effect. Pancreatic lipase inhibitory activity has been extensively used for the determination of potential efficacy of natural products as antiobesity agents. In attempts to identify natural products for overcoming obesity, more researches have been focused on the identification of newer pancreatic lipase inhibitors with less unpleasant adverse effects. In this review, we consider the potential role of plants that have been investigated for their pancreatic lipase inhibitory activity. PMID:26640503

  20. Bromotyrosine Alkaloids with Acetylcholinesterase Inhibitory Activity from the Thai Sponge Acanthodendrilla sp.

    PubMed

    Sirimangkalakitti, Natchanun; Olatunji, Opeyemi J; Changwichit, Kanokwan; Saesong, Tongchai; Chamni, Supakarn; Chanvorachote, Pithi; Ingkaninan, Kornkanok; Plubrukarn, Anuchit; Suwanborirux, Khanit

    2015-11-01

    Twenty bromotyrosine alkaloids, including a new compound, 13-oxosubereamolline D (5), were isolated from the Thai sponge Acanthodendrilla sp. Their structures were determined by analyses of 1D- and 2D-NMR, high-resolution mass, and circular dichroism data. The complete 1H and 13C NMR assignments of 5,7β-dichlorocavernicolin (19) and 5,7α-dichlorocavernicolin (20) are described herein for the first time. The acetylcholinesterase (AChE) inhibitory activity of all isolated compounds was evaluated. Only homoaerothionin (7) and fistularin 1 (10) exhibited inhibitory activity against human recombinant AChE (hrAChE) with IC50s of 4.5 and 47.5 µM, respectively. The hrAChE inhibition kinetics of 7, the most potent alkaloid, showed increased Km and unchanged Vmaxvalues, suggesting its competitive mode of inhibition. The spirocyclohexadienylisoxazole and the length of the alkyl diamine linkage were proposed as the crucial parts for its strong inhibitory activity. This finding indicates a therapeutic potential for 7 in acetylcholine-related diseases, most importantly Alzheimer's disease. PMID:26749833

  1. Angiotensin I-converting enzyme inhibitory activity of gelatin hydrolysates and identification of bioactive peptides.

    PubMed

    Herregods, Griet; Van Camp, John; Morel, Nicole; Ghesquière, Bart; Gevaert, Kris; Vercruysse, Lieselot; Dierckx, Stephan; Quanten, Erwin; Smagghe, Guy

    2011-01-26

    In this project we report on the angiotensin I-converting enzyme (ACE)-inhibitory activity of a bovine gelatin hydrolysate (Bh2) that was submitted to further hydrolysis by different enzymes. The thermolysin hydrolysate (Bh2t) showed the highest in vitro ACE inhibitory activity, and interestingly a marked in vivo blood pressure-lowering effect was demonstrated in spontaneously hypertensive rats (SHR). In contrast, Bh2 showed no effect in SHR, confirming the need for the extra thermolysin hydrolysis. Hence, an angiotensin I-evoked contractile response in isolated rat aortic rings was inhibited by Bh2t, but not by Bh2, suggesting ACE inhibition as the underlying antihypertensive mechanism for Bh2t. Using mass spectrometry, seven small peptides, AG, AGP, VGP, PY, QY, DY and IY or LY or HO-PY were identified in Bh2t. As these peptides showed ACE inhibitory activity and were more prominent in Bh2t than in Bh2, the current data provide evidence that these contribute to the antihypertensive effect of Bh2t.

  2. Dipeptidyl peptidase-IV inhibitory activity of dimeric dihydrochalcone glycosides from flowers of Helichrysum arenarium.

    PubMed

    Morikawa, Toshio; Ninomiya, Kiyofumi; Akaki, Junji; Kakihara, Namiko; Kuramoto, Hiroyuki; Matsumoto, Yurie; Hayakawa, Takao; Muraoka, Osamu; Wang, Li-Bo; Wu, Li-Jun; Nakamura, Seikou; Yoshikawa, Masayuki; Matsuda, Hisashi

    2015-10-01

    A methanol extract of everlasting flowers of Helichrysum arenarium L. Moench (Asteraceae) was found to inhibit the increase in blood glucose elevation in sucrose-loaded mice at 500 mg/kg p.o. The methanol extract also inhibited the enzymatic activity against dipeptidyl peptidase-IV (DPP-IV, IC50 = 41.2 μg/ml), but did not show intestinal α-glucosidase inhibitory activities. From the extract, three new dimeric dihydrochalcone glycosides, arenariumosides V-VII (2-4), were isolated, and the stereostructures were elucidated based on their spectroscopic properties and chemical evidence. Of the constituents, several flavonoid constituents, including 2-4, were isolated, and these isolated constituents were investigated for their DPP-IV inhibitory effects. Among them, chalconaringenin 2'-O-β-D-glucopyranoside (16, IC50 = 23.1 μM) and aureusidin 6-O-β-D-glucopyranoside (35, 24.3 μM) showed relatively strong inhibitory activities.

  3. New diterpenoids with estrogen sulfotransferase inhibitory activity from Leonurus sibiricus L.

    PubMed

    Narukawa, Yuji; Niimura, Akiko; Noguchi, Hitomi; Tamura, Hiroomi; Kiuchi, Fumiyuki

    2014-01-01

    Four new diterpenoids (1-4), along with eight known diterpenoids (5-12) were isolated from the acetone extract of Leonurus herb (aerial parts of Leonurus sibiricus L.). The structures of the compounds were determined by spectroscopic methods. Among the isolated compounds, compounds 2, 3, 8, 9 and 10 showed inhibitory activity against human liver cytosol estrogen sulfotransferase (E-ST), which plays a key role in the maintenance of cellular estrogen levels. Compound 2 showed the strongest activity with an IC50 value of 7.9 μM, which is comparable to the activity of the positive control, meclofenamic acid (IC50 5.4 μM).

  4. The availability of attentional resources modulates the inhibitory strength related to weakly activated priming.

    PubMed

    Wang, Yongchun; Wang, Yonghui; Liu, Peng; Dai, Dongyang; Di, Meilin; Chen, Qiang

    2016-08-01

    The current study investigated the role of attention in inhibitory processes (the inhibitory processes described in the current study refer only to those associated with masked or flanked priming) using a mixed paradigm involving the negative compatibility effect (NCE) and object-based attention. Accumulating evidence suggests that attention can be spread more easily within the same object, which increases the availability of attentional resources, than across different objects. Accordingly, we manipulated distractor location (with primes presented in the same object versus presented in different objects) together with prime/target compatibility (compatible versus incompatible) and prime-distractor stimulus onset asynchrony (SOA, 23 ms vs 70 ms). The aim was to investigate whether inhibitory processes related to weakly activated priming, which have been previously assumed to be automatic, depend on the availability of attentional resources. The results of Experiment 1 showed a significant NCE for the 70-ms SOA when the prime and distractor were presented in the same object (greater attentional resource availability); however, reversed NCEs were obtained for all other conditions. Experiment 2 was designed to disentangle whether the results of Experiment 1 were affected by the prime position, and the results indicated that the prime position did not modulate the NCE in Experiment 1. Together, these results are consistent with the claim that the availability of attentional resources modulates the inhibitory strength related to weakly activated priming. Specifically, if attentional resources are assigned to the distractor when it is presented in the same object as the prime, the strength of the inhibition elicited by the distractor may increase and reverse the activation elicited by the prime, which could lead to a significant NCE. PMID:27198916

  5. Growth inhibitory activity of extracts and compounds from Cimicifuga species on human breast cancer cells

    PubMed Central

    Einbond, Linda Saxe; Wen-Cai, Ye; He, Kan; Wu, Hsan-au; Cruz, Erica; Roller, Marc; Kronenberg, Fredi

    2008-01-01

    The purpose of this report is to explore the growth inhibitory effect of extracts and compounds from black cohosh and related Cimicifuga species on human breast cancer cells and to determine the nature of the active components. Black cohosh fractions enriched for triterpene glycosides and purified components from black cohosh and related Asian species were tested for growth inhibition of the ER− Her2 overexpressing human breast cancer cell line MDA-MB-453. Growth inhibitory activity was assayed using the Coulter Counter, MTT and colony formation assays. Results suggested that the growth inhibitory activity of black cohosh extracts appears to be related to their triterpene glycoside composition. The most potent Cimicifuga component tested was 25-acetyl-7,8-didehydrocimigenol 3-O-β-D-xylopyranoside, which has an acetyl group at position C-25. It had an IC50 of 3.2 µg/ml (5 µM) compared to7.2 µg/ml (12.1 µM) for the parent compound 7,8-didehydrocimigenol 3-O-β-D-xylopyranoside. Thus, the acetyl group at position C-25 enhances growth inhibitory activity. The purified triterpene glycoside actein (β-D-xylopyranoside), with an IC50 equal to 5.7 µg/ml (8.4 µM), exhibited activity comparable to cimigenol 3-O-β-D-xyloside. MCF7 (ER+Her2 low) cells transfected for Her2 are more sensitive than the parental MCF7 cells to the growth inhibitory effects of actein from black cohosh, indicating that Her2 plays a role in the action of actein. The effect of actein on Her2 overexpressing MDA-MB-453 and MCF7 (ER+Her2 low) human breast cancer cells was examined by fluorescent microscopy. Treatment with actein altered the distribution of actin filaments and induced apoptosis in these cells. These findings, coupled with our previous evidence that treatment with the triterpene glycoside actein induced a stress response and apoptosis in human breast cancer cells, suggest that compounds from Cimicifuga species may be useful in the prevention and treatment of human breast cancer

  6. Phagocytic receptors activate and immune inhibitory receptor SIRPα inhibits phagocytosis through paxillin and cofilin.

    PubMed

    Gitik, Miri; Kleinhaus, Rachel; Hadas, Smadar; Reichert, Fanny; Rotshenker, Shlomo

    2014-01-01

    The innate immune function of phagocytosis of apoptotic cells, tissue debris, pathogens, and cancer cells is essential for homeostasis, tissue repair, fighting infection, and combating malignancy. Phagocytosis is carried out in the central nervous system (CNS) by resident microglia and in both CNS and peripheral nervous system by recruited macrophages. While phagocytosis proceeds, bystander healthy cells protect themselves by sending a "do not eat me" message to phagocytes as CD47 on their surface ligates immune inhibitory receptor SIRPα on the surface of phagocytes and SIRPα then produces the signaling which inhibits phagocytosis. This helpful mechanism becomes harmful when tissue debris and unhealthy cells inhibit their own phagocytosis by employing the same mechanism. However, the inhibitory signaling that SIRPα produces has not been fully revealed. We focus here on how SIRPα inhibits the phagocytosis of the tissue debris "degenerated myelin" which hinders repair in axonal injury and neurodegenerative diseases. We tested whether SIRPα inhibits phagocytosis by regulating cytoskeleton function through paxillin and cofilin since (a) the cytoskeleton generates the mechanical forces that drive phagocytosis and (b) both paxillin and cofilin control cytoskeleton function. Paxillin and cofilin were transiently activated in microglia as phagocytosis was activated. In contrast, paxillin and cofilin were continuously activated and phagocytosis augmented in microglia in which SIRPα expression was knocked-down by SIRPα-shRNA. Further, levels of phagocytosis, paxillin activation, and cofilin activation positively correlated with one another. Taken together, these observations suggest a novel mechanism whereby paxillin and cofilin are targeted to control phagocytosis by both the activating signaling that phagocytic receptors produce by promoting the activation of paxillin and cofilin and the inhibiting signaling that immune inhibitory SIRPα produces by promoting the

  7. Discovery of Diverse Small Molecule Chemotypes with Cell-Based PKD1 Inhibitory Activity

    PubMed Central

    Sharlow, Elizabeth R.; Mustata Wilson, Gabriela; Close, David; Leimgruber, Stephanie; Tandon, Manuj; Reed, Robyn B.; Shun, Tong Ying; Wang, Q. Jane; Wipf, Peter; Lazo, John S.

    2011-01-01

    Protein kinase D (PKD) is a novel family of serine/threonine kinases regulated by diacylglycerol, which is involved in multiple cellular processes and various pathological conditions. The limited number of cell-active, selective inhibitors has historically restricted biochemical and pharmacological studies of PKD. We now markedly expand the PKD1 inhibitory chemotype inventory with eleven additional novel small molecule PKD1 inhibitors derived from our high throughput screening campaigns. The in vitro IC50s for these eleven compounds ranged in potency from 0.4 to 6.1 µM with all of the evaluated compounds being competitive with ATP. Three of the inhibitors (CID 1893668, (1Z)-1-(3-ethyl-5-methoxy-1,3-benzothiazol-2-ylidene)propan-2-one; CID 2011756, 5-(3-chlorophenyl)-N-[4-(morpholin-4-ylmethyl)phenyl]furan-2-carboxamide; CID 5389142, (6Z)-6-[4-(3-aminopropylamino)-6-methyl-1H-pyrimidin-2-ylidene]cyclohexa-2,4-dien-1-one) inhibited phorbol ester-induced endogenous PKD1 activation in LNCaP prostate cancer cells in a concentration-dependent manner. The specificity of these compounds for PKD1 inhibitory activity was supported by kinase assay counter screens as well as by bioinformatics searches. Moreover, computational analyses of these novel cell-active PKD1 inhibitors indicated that they were structurally distinct from the previously described cell-active PKD1 inhibitors while computational docking of the new cell-active compounds in a highly conserved ATP-binding cleft suggests opportunities for structural modification. In summary, we have discovered novel PKD1 inhibitors with in vitro and cell-based inhibitory activity, thus successfully expanding the structural diversity of small molecule inhibitors available for this important pharmacological target. PMID:21998636

  8. Melanogenesis-inhibitory activity and cancer chemopreventive effect of glucosylcucurbic acid from shea (Vitellaria paradoxa) kernels.

    PubMed

    Zhang, Jie; Kurita, Masahiro; Ebina, Kodai; Ukiya, Motohiko; Tokuda, Harukuni; Yasukawa, Ken; Masters, Eliot T; Shimizu, Naoto; Akihisa, Momoko; Feng, Feng; Akihisa, Toshihiro

    2015-04-01

    Two jasmonate derivatives, glucosylcucurbic acid (1) and methyl glucosylcucurbate (2), were isolated from the MeOH extract of defatted shea (Vitellaria paradoxa; Sapotaceae) kernels. These and their deglucosylated derivatives, cucurbic acid (3) and methyl cucurbate (4), were evaluated for their melanogenesis-inhibitory and cancer chemopreventive potencies. Compounds 1, 3, and 4 exhibited potent melanogenesis-inhibitory activities in α-melanocyte-stimulating hormone (α-MSH)-stimulated B16 melanoma cells. Western-blot analysis revealed that compounds 1 and 3 reduced the protein levels of MITF (=microphthalmia-associated transcription factor), tyrosinase, TRP-1 (=tyrosine-related protein 1), and TRP-2 mostly in a concentration-dependent manner. In addition, compound 1 exhibited inhibitory effects against Epstein-Barr virus early antigen (EBV-EA) activation induced with 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, against TPA-induced inflammation in mice, and against skin tumor promotion in an in vivo two-stage mouse skin carcinogenesis test based on 7,12-dimethylbenz[a]anthracene (DMBA) as initiator, and with TPA as promoter. PMID:25879500

  9. Absolute Configurations and NO Inhibitory Activities of Terpenoids from Curcuma longa.

    PubMed

    Xu, Jing; Ji, Feifei; Kang, Jing; Wang, Hao; Li, Shen; Jin, Da-Qing; Zhang, Qiang; Sun, Hongwei; Guo, Yuanqiang

    2015-06-24

    Curcuma longa L., belonging to the Zingiberaceae family, is a perennial herb and has been used as a spice and a pigment in the food industry. In the ongoing search for inhibitory reagents of NO production and survey of the chemical composition of natural vegetable foods, the chemical constituents of C. longa used as spice were investigated. This investigation resulted in the isolation of 2 new terpenoids and 14 known analogues. Their structures were established on the basis of the extensive analyses of 1D and 2D NMR spectroscopic data, and the absolute configurations of 1-4 were elucidated by comparison of the calculated and experimental ECD spectra. Among them, compound 1 is a rare norditerpene with an ent-labdane skeleton, and 2 is a skeletally novel sesquiterpene having an eight-membered ring. All of the compounds were found to possess NO inhibitory activities in murine microglial BV-2 cells. The discovery of two new compounds in this chemical investigation further disclosed the chemical composition of C. longa used a food spice, and the bioassay implied that the natural food spice C. longa, containing terpenoids with NO inhibitory activities, may be potentially promotive to human health.

  10. Inhibitory activity of cigarette-smoke condensate on the mutagenicity of heterocyclic amines.

    PubMed

    Lee, C K; Munoz, J A; Fulp, C; Chang, K M; Rogers, J C; Borgerding, M F; Doolittle, D J

    1994-07-01

    Cigarette-smoke condensate (CSC) is a complex mixture containing over 3800 identified chemicals including nicotine, water, mutagens, antimutagens, cytotoxins and inert chemicals. Although CSC is mutagenic in the Ames test, its effect on the activity of other mutagens has not been characterized. Using the Ames Salmonella bacterial mutagenesis assay, we found CSC exerts a significant inhibitory effect on mutagens requiring bioactivation. Those studied included heterocyclic amines (Glu-P-1, Glu-P-2, IQ, MeIQ, Trp-P-1 and Trp-P-2), benzo[a]pyrene (B[a]P) and aflatoxin B1. However, CSC had no effect on the activity of direct-acting mutagens (2-nitrofluorene, sodium azide, 4-nitro-1,2-phenylenediamine, 4-nitroquinoline N-oxide and methyl methanesulfonate). With indirect-acting mutagens, the reduced number of revertants observed in the presence of CSC was not attributable to cytotoxicity. CSC exhibited a potent inhibitory effect on the cytochrome P-450 dependent monooxygenases, ethoxyresorufin O-deethylase and B[a]P hydroxylase. This suggests inhibition of the cytochrome P-450 isozymes as one possible mechanism for the antimutagenicity of CSC. Fractionation studies of CSC revealed that the neutral, weakly acidic (phenolic) and basic fractions are all effective as antimutagens against Glu-P-1, a representative heterocyclic amine. This indicates that several classes of chemicals contribute to the inhibitory effect of CSC on the mutagenicity of the heterocyclic amines. PMID:7517501

  11. Isolation, characterization, and NO inhibitory activities of sesquiterpenes from Blumea balsamifera.

    PubMed

    Xu, Jing; Jin, Da-qing; Liu, Cuizhou; Xie, Chunfeng; Guo, Yuanqiang; Fang, Lingzhi

    2012-08-15

    Blumea balsamifera belongs to the family Compositae, and its leaves have been used as a flavoring ingredient and a tea. A phytochemical investigation of the aerial parts of B. balsamifera led to the isolation of 10 new (1-10) and 1 known (11) sesquiterpenes. Their structures were elucidated on the basis of extensive one- and two-dimensional nuclear magnetic resonance (heteronuclear multiple-quantum coherence, heteronuclear multiple-bond correlation, (1)H-(1)H correlation spectroscopy, and nuclear Overhauser effect spectrometry) spectroscopic data analyses, and the structure of compound 1 was confirmed by X-ray crystallography. The inhibitory activities on lipopolysaccharide-induced NO production in murine microglial BV-2 cells of these sesquiterpenes were evaluated, and all of the compounds showed inhibitory effects. PMID:22823402

  12. New compound with DNA Topo I inhibitory activity purified from Penicillium oxalicum HSY05.

    PubMed

    Liu, Bing; Wang, Hai-Feng; Zhang, Li-Hua; Liu, Fang; He, Feng-Jun; Bai, Jiao; Hua, Hui-Ming; Chen, Gang; Pei, Yue-Hu

    2015-01-01

    Strain HSY05 was isolated from sea sediment collected from the South China Sea and was later identified as Penicillium oxalicum by 16S rDNA sequence analysis. Various chromatographic processes led to the isolation and purification of two metabolites from the fermentation culture of HSY05, including one new compound, 2,2',4,4'-tetrahyoxy-8'-methyl-6-methoxy-acyl-ethyl-diphenylmethanone (1), and a known compound secalonic acid D (SAD, 2), as characterised by UV, IR, 1D, 2D-NMR and MS data. The inhibitory activities against topoisomerase I of these two compounds were evaluated. The result showed that in addition to the known topo I inhibitor SAD (2), compound 1 also exhibited a moderate inhibitory effect.

  13. Chemical constituents of Swertia longifolia Boiss. with α-amylase inhibitory activity

    PubMed Central

    Saeidnia, Soodabeh; Ara, Leila; Hajimehdipoor, Homa; Read, Roger W.; Arshadi, Sattar; Nikan, Marjan

    2016-01-01

    α-Amylase inhibitors play a critical role in the control of diabetes and many of medicinal plants have been found to act as α-amylase inhibitors. Swertia genus, belonging to the family Gentianaceae, comprises different species most of which have been used in traditional medicine of several cultures as antidiabetic, anti-pyretic, analgesic, liver and gastrointestinal tonic. Swertia longifolia Boiss. is the only species of Swertia growing in Iran. In the present investigation, phytochemical study of S. longifolia was performed and α-amylase inhibitory effects of the plant fractions and purified compounds were determined. Aerial parts of the plant were extracted with hexane, chloroform, methanol and water, respectively. The components of the hexane and chloroform fractions were isolated by different chromatographic methods and their structures were determined by 1H NMR and 13C NMR data. α-Amylase inhibitory activity was determined by a colorimetric assay using 3,5-dinitro salysilic acid. During phytochemical examination, α-amyrin, β-amyrin and β-sitosterol were purified from the hexane fraction, while ursolic acid, daucosterol and swertiamarin were isolated from chloroform fraction. The results of the biochemical assay revealed α-amylase inhibitory activity of hexane, chloroform, methanol and water fractions, of which the chloroform and methanol fractions were more potent (IC50 16.8 and 18.1 mg/ml, respectively). Among examined compounds, daucosterol was found to be the most potent α-amylase inhibitor (57.5% in concentration 10 mg/ml). With regard to α-amylase inhibitory effects of the plant extracts, purified constituents, and antidiabetic application of the species of Swertia genus in traditional medicine of different countries, S. longifolia seems more appropriate species for further mechanistic antidiabetic evaluations. PMID:27051429

  14. Increased alpha band activity indexes inhibitory competition across a border during figure assignment.

    PubMed

    Sanguinetti, Joseph L; Trujillo, Logan T; Schnyer, David M; Allen, John J B; Peterson, Mary A

    2016-09-01

    Figure-ground assignment is thought to entail inhibitory competition between potential objects on opposite sides of a shared border; the winner is perceived as the figure, and the loser as the shapeless ground. Computational models and response time measures support this understanding but to date no online measure of inhibitory competition during figure-ground assignment has been reported. The current study assays electroencephalogram (EEG) alpha power as a measure of inhibitory competition during figure-ground assignment. Activity in the EEG alpha band has been linked to functional inhibition in the brain, and it has been proposed that increased alpha power reflects increased inhibition. In 2 experiments participants viewed silhouettes designed so that the insides would be perceived as figures. Real-world silhouettes depicted namable objects. Novel silhouettes depicted novel objects on the insides of their borders, but varied in the amount of hypothesized cross-border competition for figural status: In "Low-Competition" silhouettes, the borders suggested novel objects on the outside as well as on the inside. In "High-Competition" silhouettes the borders suggested portions of real-world objects on the outside; these compete with the figural properties favoring the inside as figure. Participants accurately categorized both types of novel silhouettes as "novel" objects and were unaware of the real world objects suggested on the outside of the High-Competition silhouettes. In both experiments, we observed more alpha power while participants viewed High- rather than Low-Competition novel silhouettes. These are the first results to show via an online index of neural activity that figure assignment entails inhibitory competition.

  15. Chemical constituents of Swertia longifolia Boiss. with α-amylase inhibitory activity.

    PubMed

    Saeidnia, Soodabeh; Ara, Leila; Hajimehdipoor, Homa; Read, Roger W; Arshadi, Sattar; Nikan, Marjan

    2016-01-01

    α-Amylase inhibitors play a critical role in the control of diabetes and many of medicinal plants have been found to act as α-amylase inhibitors. Swertia genus, belonging to the family Gentianaceae, comprises different species most of which have been used in traditional medicine of several cultures as antidiabetic, anti-pyretic, analgesic, liver and gastrointestinal tonic. Swertia longifolia Boiss. is the only species of Swertia growing in Iran. In the present investigation, phytochemical study of S. longifolia was performed and α-amylase inhibitory effects of the plant fractions and purified compounds were determined. Aerial parts of the plant were extracted with hexane, chloroform, methanol and water, respectively. The components of the hexane and chloroform fractions were isolated by different chromatographic methods and their structures were determined by (1)H NMR and (13)C NMR data. α-Amylase inhibitory activity was determined by a colorimetric assay using 3,5-dinitro salysilic acid. During phytochemical examination, α-amyrin, β-amyrin and β-sitosterol were purified from the hexane fraction, while ursolic acid, daucosterol and swertiamarin were isolated from chloroform fraction. The results of the biochemical assay revealed α-amylase inhibitory activity of hexane, chloroform, methanol and water fractions, of which the chloroform and methanol fractions were more potent (IC50 16.8 and 18.1 mg/ml, respectively). Among examined compounds, daucosterol was found to be the most potent α-amylase inhibitor (57.5% in concentration 10 mg/ml). With regard to α-amylase inhibitory effects of the plant extracts, purified constituents, and antidiabetic application of the species of Swertia genus in traditional medicine of different countries, S. longifolia seems more appropriate species for further mechanistic antidiabetic evaluations. PMID:27051429

  16. Biflavonoids of Dacrydium balansae with potent inhibitory activity on dengue 2 NS5 polymerase.

    PubMed

    Coulerie, Paul; Eydoux, Cécilia; Hnawia, Edouard; Stuhl, Laetitia; Maciuk, Alexandre; Lebouvier, Nicolas; Canard, Bruno; Figadère, Bruno; Guillemot, Jean-Claude; Nour, Mohammed

    2012-05-01

    In order to find new molecules for antiviral drug design, we screened 102 ethyl acetate extracts from New-Caledonian flora for antiviral activity against the dengue 2 virus RNA-dependant RNA polymerase (DV-NS5 RdRp). The leaf extract of Dacrydium balansae, which strongly inhibited the DV-NS5, was submitted to bioguided fractionation. Four biflavonoids ( 1- 4), three sterols ( 5- 7), and two stilbene derivatives ( 8- 9) were identified and evaluated for their antiviral potential on the DV-NS5 RdRp. Biflavonoids appeared to be potent inhibitors of DV-NS5 RdRp with IC (50)s between 0.26 and 3.12 µM. Inhibitory activity evaluations against the RNA polymerase from other Flaviviridae viruses allowed us to conclude that these compounds are specific inhibitors of the DV RNA polymerase. The strongest inhibitions were observed with hinokiflavone ( 4), but podocarpusflavone A ( 2) is the strongest noncytotoxic inhibitor of the DV-NS5 and it also displayed polymerase inhibitory activity in a DV replicon. A preliminary structure-activity relationship study (SARs) revealed the necessity of the biflavonoid skeleton, the influence of number and position of methoxylations, and the importance of a free rotation of the linkage between the two apigenin monomers of the biflavonoids. To the best of our knowledge, podocarpusflavone A ( 2) is the strongest noncytotoxic non-nucleotide molecule exhibiting a specific inhibitory activity against the RNA polymerase domain of DV-NS5 and thus is promising for chemotherapy development against dengue fever. PMID:22411725

  17. Trivalent metal ions based on inorganic compounds with in vitro inhibitory activity of matrix metalloproteinase 13.

    PubMed

    Wen, Hanyu; Qin, Yuan; Zhong, Weilong; Li, Cong; Liu, Xiang; Shen, Yehua

    2016-10-01

    Collagenase-3 (MMP-13) inhibitors have attracted considerable attention in recent years and have been developed as a therapeutic target for a variety of diseases, including cancer. Matrix metalloproteinases (MMPs) can be inhibited by a multitude of compounds, including hydroxamic acids. Studies have shown that materials and compounds containing trivalent metal ions, particularly potassium hexacyanoferrate (III) (K3[Fe(CN)6]), exhibit cdMMP-13 inhibitory potential with a half maximal inhibitory concentration (IC50) of 1.3μM. The target protein was obtained by refolding the recombinant histidine-tagged cdMMP-13 using size exclusion chromatography (SEC). The secondary structures of the refolded cdMMP-13 with or without metal ions were further analyzed via circular dichroism and the results indicate that upon binding with metal ions, an altered structure with increased domain stability was obtained. Furthermore, isothermal titration calorimetry (ITC) experiments demonstrated that K3[Fe(CN)6]is able to bind to MMP-13 and endothelial cell tube formation tests provide further evidence for this interaction to exhibit anti-angiogenesis potential. To the best of our knowledge, no previous report of an inorganic compound featuring a MMP-13 inhibitory activity has ever been reported in the literature. Our results demonstrate that K3[Fe(CN)6] is useful as a new effective and specific inhibitor for cdMMP-13 which may be of great potential for future drug screening applications. PMID:27542739

  18. Screening of plants containing Naja naja siamensis cobra venom inhibitory activity using modified ELISA technique.

    PubMed

    Daduang, Sakda; Sattayasai, Nison; Sattayasai, Jintana; Tophrom, Pattara; Thammathaworn, Achra; Chaveerach, Arunrat; Konkchaiyaphum, Monruedee

    2005-06-15

    Enzyme-linked immunosorbent assay (ELISA) has been modified for screening plants with antagonistic activity to Naja naja siamensis cobra venom. Aqueous extracts from plants were investigated for their inhibitory effects on the binding of anti-cobra venom antibody to antigen, cobra venom, fixed onto 96-well microtiter plates. Ingredients in extracts were allowed to react with immobilized venom before the subsequent addition of antivenom antibody. Venom components affected by exposure to the extracts, unable to interact with their specific antibody, were predicted to be unable to bind to their native destinations or natural receptors. Curcuma cf. zedoaria, an old Thai medicinal plant, showed clear inhibitory activity in the ELISA test. Neurotoxin and protein degradative enzymes, major components in venom, were identified as targets of this extract in Western immunoblotting analysis. Ingredients in the extract showed high affinity to the toxin in competition assay by immunoprecipitation. The extract attenuated toxin activity by extending contraction time of diaphragm muscle after envenomation and had a potency to protect cellular proteins from venom degradative enzymes. Curcuma parviflora, with less activity in ELISA, exhibited acceptable results in two experiments but negative results in two experiments, whereas Curcuma longa, having low activity in the ELISA test, never showed any favorable results. Screening of 36 samples could classify plants into an inhibition range of 0 to 86%. This modified ELISA is recommended as a preliminary screening method for inhibitors with a large number of samples.

  19. Ongoing Network State Controls the Length of Sleep Spindles via Inhibitory Activity

    PubMed Central

    Barthó, Péter; Slézia, Andrea; Mátyás, Ferenc; Faradzs-Zade, Lejla; Ulbert, István; Harris, Kenneth D.; Acsády, László

    2014-01-01

    Summary Sleep spindles are major transient oscillations of the mammalian brain. Spindles are generated in the thalamus; however, what determines their duration is presently unclear. Here, we measured somatic activity of excitatory thalamocortical (TC) cells together with axonal activity of reciprocally coupled inhibitory reticular thalamic cells (nRTs) and quantified cycle-by-cycle alterations in their firing in vivo. We found that spindles with different durations were paralleled by distinct nRT activity, and nRT firing sharply dropped before the termination of all spindles. Both initial nRT and TC activity was correlated with spindle length, but nRT correlation was more robust. Analysis of spindles evoked by optogenetic activation of nRT showed that spindle probability, but not spindle length, was determined by the strength of the light stimulus. Our data indicate that during natural sleep a dynamically fluctuating thalamocortical network controls the duration of sleep spindles via the major inhibitory element of the circuits, the nRT. PMID:24945776

  20. Inhibitory short-term plasticity modulates neuronal activity in the rat entopeduncular nucleus in vitro.

    PubMed

    Lavian, Hagar; Korngreen, Alon

    2016-04-01

    The entopeduncular nucleus (EP) is one of the basal ganglia output nuclei integrating synaptic information from several pathways within the basal ganglia. The firing of EP neurons is modulated by two streams of inhibitory synaptic transmission, the direct pathway from the striatum and the indirect pathway from the globus pallidus. These two inhibitory pathways continuously modulate the firing of EP neurons. However, the link between these synaptic inputs to neuronal firing in the EP is unclear. To investigate this input-output transformation we performed whole-cell and perforated-patch recordings from single neurons in the entopeduncular nucleus in rat brain slices during repetitive stimulation of the striatum and the globus pallidus at frequencies within the in vivo activity range of these neurons. These recordings, supplemented by compartmental modelling, showed that GABAergic synapses from the striatum, converging on EP dendrites, display short-term facilitation and that somatic or proximal GABAergic synapses from the globus pallidus show short-term depression. Activation of striatal synapses during low presynaptic activity decreased postsynaptic firing rate by continuously increasing the inter-spike interval. Conversely, activation of pallidal synapses significantly affected postsynaptic firing during high presynaptic activity. Our data thus suggest that low-frequency striatal output may be encoded as progressive phase shifts in downstream nuclei of the basal ganglia while high-frequency pallidal output may continuously modulate EP firing.

  1. Inhibitory effect of flavonoid derivatives on Epstein-Barr virus activation and two-stage carcinogenesis of skin tumors.

    PubMed

    Iwase, Y; Takemura, Y; Ju-ichi, M; Mukainaka, T; Ichiishi, E; Ito, C; Furukawa, H; Yano, M; Tokuda, H; Nishino, H

    2001-11-28

    To search for possible anti-tumor promoters, ten flavonoid derivatives (1-10) synthesized from morin and quercetin were examined for their inhibitory effects on the Epstein-Barr virus early antigen (EBV-EA) activation by a short-term in vitro assay. Of these compounds, pentaallyl ethers (9, 10) showed significant inhibitory effects on EBV-EA activation induced by the tumor promoter, 12-O-tetradecanoylphorbol 13-acetate. Further, quercetin pentaallyl ether (10) exhibited remarkable inhibitory effects on mouse skin tumor promotion in an in vivo two-stage carcinogenesis test.

  2. Synthesis of Triazole Schiff’s Base Derivatives and Their Inhibitory Kinetics on Tyrosinase Activity

    PubMed Central

    Wang, Hui-Fang; Zheng, Jing; Cui, Yi; Fang, Xin-Yu; Zhang, Lin-Min; Chen, Qing-Xi

    2015-01-01

    In the present study, new Schiff’s base derivatives: (Z)-4-amino-5-(2-(3- fluorobenzylidene)hydrazinyl)-4H-1,2,4-triazole-3-thiol (Y1), (Z)-3-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y2), (Z)-2-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y3) and 3-((Z)-(2-(4- (((E)-3-hydroxybenzylidene)amino)-5-mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y4) were synthesized and their structures were characterized by LC-MS, IR and 1H NMR. The inhibitory effects of these compounds on tyrosinase activites were evaluated. Compounds Y1, Y2 and Y3 showed potent inhibitory effects with respective IC50 value of 12.5, 7.0 and 1.5 μM on the diphenolase activities. Moreover, the inhibition mechanisms were determined to be reversible and mixed types. Interactions of the compounds with tyrosinase were further analyzed by fluorescence quenching, copper interaction, and molecular simulation assays. The results together with the anti-tyrosinase activities data indicated that substitution on the second position of benzene ring showed superior ant-ityrosinase activities than that on third position, and that hydroxyl substitutes were better than fluorine substitutes. In addition, two benzene rings connecting to the triazole ring would produce larger steric hindrance, and affect the bonding between tyrosinase and inhibitors to decrease the inhibitory effects. The anti-tyrosinase effects of these compounds were in contrast to their antioxidant activities. In summary, this research will contribute to the development and design of antityrosinase agents. PMID:26422245

  3. Synthesis of Triazole Schiff's Base Derivatives and Their Inhibitory Kinetics on Tyrosinase Activity.

    PubMed

    Yu, Feng; Jia, Yu-Long; Wang, Hui-Fang; Zheng, Jing; Cui, Yi; Fang, Xin-Yu; Zhang, Lin-Min; Chen, Qing-Xi

    2015-01-01

    In the present study, new Schiff's base derivatives: (Z)-4-amino-5-(2-(3- fluorobenzylidene)hydrazinyl)-4H-1,2,4-triazole-3-thiol (Y1), (Z)-3-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y2), (Z)-2-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y3) and 3-((Z)-(2-(4- (((E)-3-hydroxybenzylidene)amino)-5-mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y4) were synthesized and their structures were characterized by LC-MS, IR and 1H NMR. The inhibitory effects of these compounds on tyrosinase activites were evaluated. Compounds Y1, Y2 and Y3 showed potent inhibitory effects with respective IC50 value of 12.5, 7.0 and 1.5 μM on the diphenolase activities. Moreover, the inhibition mechanisms were determined to be reversible and mixed types. Interactions of the compounds with tyrosinase were further analyzed by fluorescence quenching, copper interaction, and molecular simulation assays. The results together with the anti-tyrosinase activities data indicated that substitution on the second position of benzene ring showed superior ant-ityrosinase activities than that on third position, and that hydroxyl substitutes were better than fluorine substitutes. In addition, two benzene rings connecting to the triazole ring would produce larger steric hindrance, and affect the bonding between tyrosinase and inhibitors to decrease the inhibitory effects. The anti-tyrosinase effects of these compounds were in contrast to their antioxidant activities. In summary, this research will contribute to the development and design of antityrosinase agents. PMID:26422245

  4. Alpha-amylase inhibitory activity and phytochemical study of Zhumeria majdae Rech. f. and Wendelbo

    PubMed Central

    Mirshafie, Behnaz; Mokhber-Dezfouli, Najmeh; Manayi, Azadeh; Saeidnia, Soodabeh; Ajani, Yousef; Gohari, Ahmad Reza

    2015-01-01

    Background: Zhumeria majdae (Lamiaceae) is an endemic species growing in the South parts of Iran especially Hormozgan province. The plant is so-called Mohrekhosh locally and widely used for medicinal purposes including stomachache and dysmenorrhea. Objective: In order to separation and identification of the main flavonoid glycosides of the plant (aerial parts including leaves, stems, flowers, and fruits were used) and evaluation of its alpha-amylase inhibitory (AAI) activity, methanolic extract was prepared and fractionated to botanolic portion. Materials and Methods: Isolation of the main compounds of the butanol extract of the plant have been performed using different column chromatography methods such as high-performance liquid chromatography (C18 column) and Sephadex LH-20 as well. The isolated compounds were identified by Hydrogen-1 nuclear magnetic resonance and Carbon-13 nuclear magnetic resonance spectra and comparison with those reported in previous literature. Moreover, inhibitory activity of the butanolic extract of the plant against alpha-amylase enzyme was examined in different concentrations (15–30 mg/mL), where acarbose used as a positive control. Results: Three flavonoid glycosides: Linarin (1), hispidulin-7-O-(4-O-acetyl-rutinoside) (2), hispidulin-7-O-rutinoside (3) were successfully identified in the extract. The activity of alpha amylase enzyme was dose-dependently suppressed by the butanol extract. The extract exhibited the highest inhibition at 30 mg/mL toward enzyme (77.9 ± 2.1%), while acarbose inhibited the enzyme at 20 mg/mL by 73.9 ± 1.9%. The inhibitory concentrations of 50% for the extract and acarbose were calculated at 24.5 ± 2.1 and 6.6 ± 3.1 mg/mL, respectively. Conclusion: Z. majdae contains glycosylated flavones and could be a good candidate for anti-diabetic evaluations in animal and clinical trials due to possessing AAI activity. PMID:26692743

  5. Definition of an electronic profile of compounds with inhibitory activity against hematin aggregation in malaria parasite.

    PubMed

    Portela, César; Afonso, Carlos M M; Pinto, Madalena M M; Ramos, Maria João

    2004-06-15

    Malaria is one of the most important parasitic diseases, affecting almost half of the world and posing a threat to the other half. Xanthone derivatives can behave as antimalarial drugs in the same mechanistic way as chloroquine and other related quinolines. This action is due to the inhibition of the detoxification pathway of the parasite, responsible for the production of hemozoin. We report a study of the electronic properties of the xanthonic and quinolinic compounds based on DFT calculations, in order to determine a pattern that could be applied to the development of new potentially active antimalarial molecules. As a result, a new interpretation of structure-activity relationship of the quinoline antimalarial drugs, and of the active hydroxylated xanthones is proposed here. We conclude that electronic features rather than steric factors control primarily the inhibitory activity of the studied compounds against hematin aggregation, concurring to a potential antimalarial activity.

  6. Growth-inhibitory activity of natural and synthetic isothiocyanates against representative human microbial pathogens

    PubMed Central

    Kurepina, Natalia; Kreiswirth, Barry N.; Mustaev, Arkady

    2013-01-01

    Aims The aim of this study was to test the growth inhibition activity of isothiocyanates (ITC), defense compounds of plants, against common human microbial pathogens. Methods and Results In this study we have tested the growth inhibitory activity of a diverse collection of new and previously known representative ITC of various structural classes against pathogenic bacteria, fungi and molds by a serial dilution method. Generally, the compounds were more active against Gram-positive bacteria and fungi exhibiting species-specific bacteriostatic or bactericidal effect. The most active compounds inhibited the growth of both drug-susceptible and multi drug resistant (MDR) pathogens at micromolar concentrations. In the case of Mycobacterium tuberculosis some compounds were more active against MDR, rather than against susceptible strains. The average anti-microbial activity for some of new derivatives was significantly higher than previously reported for the most active ITC compounds. The structure-activity relationship (SAR) established for various classes of ITC with Bacillus cereus (model organism for B. anthracis) followed a distinct pattern, thereby enabling prediction of new more efficient inhibitors. Remarkably, tested bacteria failed to develop resistance to ITC. While effectively inhibiting microbial growth, ITCs displayed moderate toxicity towards eukaryotic cells. Conclusions High antimicrobial activity coupled with moderate toxicity grants further thorough studies of the ITC compounds aimed at elucidation of their cellular targets and inhibitory mechanism. Significance and impact of the study This systematic study identified new ITC compounds highly active against common human microbial pathogens at the concentrations comparable with those for currently used antimicrobial drugs (e.g. rifampicin, fluconazole). Tested representative pathogens do not develop resistance to the inhibitors. These properties justify further evaluation of ITC compounds as potential

  7. Biotransformation of isoimperatorin and imperatorin by Glomerella cingulata and beta-secretase inhibitory activity.

    PubMed

    Marumoto, Shinsuke; Miyazawa, Mitsuo

    2010-01-01

    Biotransformation studies conducted on the furanocoumarins isoimperatorin (1) and imperatorin (3) have revealed that 1 was metabolized by Glomerella cingulata to give the corresponding reduced acid, 6,7-furano-5-prenyloxy hydrocoumaric acid (2), and 3 was transformed by G. cingulata to give the dealkylated metabolite, xanthotoxol (4) in high yields (83% and 81%), respectively. The structures of the new compound 2 have been established on the basis of spectral data. The metabolites 2 and 4 were tested for the beta-secretase (BACE1) inhibitory activity in vitro, and metabolite 2 slightly inhibited the beta-secretase activity with an IC(50) value of 185.6+/-6.8 microM. The metabolite 4 was less potent activity than compounds 1-3. In addition, methyl ester (2Me), methyl ether (2a) and methyl ester and ether (2aMe) of 2 were synthesized, and investigated for the ability to inhibit beta-secretase. Compound 2aMe exhibited the best beta-secretase inhibitory activity at the IC(50) value 16.2+/-1.2 microM and found to be the 2aMe showed competitive mode of inhibition against beta-secretase with K(i) value 11.3+/-2.8 microM. PMID:19939683

  8. Phenolics from strawberry cv. Falandi and their antioxidant and α-glucosidase inhibitory activities.

    PubMed

    Yang, Dan; Xie, Haihui; Jiang, Yueming; Wei, Xiaoyi

    2016-03-01

    Three new phenolic glucosides, falandiosides A (1), B (2), and C (6) were isolated from strawberry (Fragaria×ananassa Duch.) cv. Falandi fruit, together with three flavone glucuronides (3-5), eleven lignan glycosides (12-22), and five others. Their structures were determined by spectroscopic methods. All the known phenolics were reported from strawberry for the first time. They were evaluated for antioxidant and α-glucosidase inhibitory activities. Three new and fifteen known phenolics showed potent 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical cation scavenging activity with IC50 values of 22.50-4.28μM in comparison to l-ascorbic acid (14.21μM). Quercetin 3-(6-methylglucuronide) (4), (+)-isolariciresinol 9'-glucoside (12), and (-)-isolariciresinol 9'-glucoside (13) were active in scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. Moreover, compounds 12 and 13 had moderate ferric reducing antioxidant power (FRAP) values. Further, two new and seven known phenolics exhibited more potent α-glucosidase inhibitory activity with IC50 values of 537.43-25.39μM than acarbose (619.94μM).

  9. Nanocapsular dispersion of cinnamaldehyde for enhanced inhibitory activity against aflatoxin production by Aspergillus flavus.

    PubMed

    Li, Hongbo; Shen, Qingshan; Zhou, Wei; Mo, Haizhen; Pan, Daodong; Hu, Liangbin

    2015-01-01

    Cinnamaldehyde (CA) is marginally soluble in water, making it challenging to evenly disperse it in foods, and resulting in lowered anti-A. flavus efficacy. In the present study, nano-dispersed CA (nano-CA) was prepared to increase its aqueous solubility. Free and nano-dispersed CA were compared in terms of their inhibitory activity against fungal growth and aflatoxin production of A. flavus both in Sabouraud Dextrose (SD) culture and in peanut butter. Our results indicated that free CA inhibited the mycelia growth and aflatoxin production of A. flavus with a minimal inhibitory concentration (MIC) value of 1.0 mM, but promoted the aflatoxin production at some concentrations lower than the MIC. Nano-CA had a lower MIC value of 0.8 mM against A. flavus, and also showed improved activity against aflatoxin production without the promotion at lower dose. The solidity of peanut butter had an adverse impact on the antifungal activity of free CA, whereas nano-dispersed CA showed more than 2-fold improved activity against the growth of A. flavus. Free CA still promoted AFB1 production at the concentration of 0.25 mM, whereas nano-CA showed more efficient inhibition of AFB1 production in the butter. PMID:25853318

  10. T Cells Expressing Constitutively Active Akt Resist Multiple Tumor-associated Inhibitory Mechanisms

    PubMed Central

    Sun, Jiali; Dotti, Gianpietro; Huye, Leslie E; Foster, Aaron E; Savoldo, Barbara; Gramatges, Maria M; Spencer, David M; Rooney, Cliona M

    2010-01-01

    Adoptive transfer of antigen-specific cytotoxic T lymphocytes has shown promise for the therapy of cancer. However, tumor-specific T cells are susceptible to diverse inhibitory signals from the tumor microenvironment. The Akt/protein kinase B plays a central role in T-cell proliferation, function, and survival and we hypothesized that expression of constitutively active Akt (caAkt) in T cells could provide resistance to many of these tumor-associated inhibitory mechanisms. caAkt expression in activated human T cells increased proliferation and cytokine production, a likely result of their sustained expression of nuclear factor-κB (NF-κB) and provided resistance to apoptosis by upregulating antiapoptotic molecules. caAkt expressing T cells (caAkt-T-cells) were also relatively resistant to suppression by and conversion into regulatory T cells (Tregs). These characteristics provided a survival advantage to T cells cocultured with tumor cells in vitro; CD3/28-stimulated T cells expressing a chimeric antigen receptor (CAR) specific for disialoganglioside (GD2) that redirected their activity to the immunosuppressive, GD2-expressing neuroblastoma cell line, LAN-1, resisted tumor-induced apoptosis when co-expressing transgenic caAkt. In conclusion, caAkt-transduced T cells showed resistance to several evasion strategies employed by tumors and may therefore enhance the antitumor activity of adoptively transferred T lymphocytes. PMID:20842106

  11. Inhibitory activity against plasmin, trypsin, and elastase in rennet whey and in cheese fortified with whey protein.

    PubMed

    Benfeldt, C; Sørensen, J; Petersen, T E

    1998-03-01

    The inhibitory activity against trypsin, elastase, and plasmin was determined in samples of Danbo 45+ that were manufactured from milk pasteurized at 72, 80, and 90 degrees C for 15, 30 and 60 s; the corresponding rennet wheys; and Havarti 45+ manufactured from milk concentrated 1.8-fold, 2.7-fold, and 4.6-fold by ultrafiltration. A sensitive colorimetric assay demonstrated that the incorporation of thermally denatured whey proteins into the cheese curd by pasteurization resulted in a decreased proteinase inhibitory activity against trypsin and elastase in Danbo 45+ and against trypsin, elastase, and plasmin in the corresponding rennet wheys. However, incorporation of native whey proteins into Havarti 45+ by ultrafiltration of the cheese milk resulted in an increased inhibitory activity against trypsin and elastase in the cheeses. Cheese manufactured from milk concentrated 1.8-fold, 2.7-fold, or 4.6-fold displayed trypsin inhibitory activity that was 1.8, 2.9, and 5.1 times, respectively, that of the reference cheese. Similarly, the elastase inhibitory activity in the cheeses increased 2.2, 3.2 and 7.8 times. The increased inhibitory activity in cheese fortified with native whey protein likely contributes to the decreased proteolysis and altered ripening characteristics of the resulting cheeses, and further, the method can be adapted to detection of other inhibitors if sufficiently sensitive substrates are available.

  12. Flavonoids and its derivatives from Callistephus chinensis flowers and their inhibitory activities against alpha-glucosidase

    PubMed Central

    Zhang, Xiaoshu; Liu, Zhenting; Bi, Xiuli; Liu, Jingxin; Li, Wei; Zhao, Yuqing

    2013-01-01

    Inhibitors of carbohydrate-hydrolysing enzymes play an important role for the treatment of diabetes. One of the therapeutic methods for decreasing of postprandial hyperglycemia is to retard absorption of glucose by the inhibition of carbohydrate- hydrolysing enzymes, such as α-glucosidase, in the digestive organs. To investigate the therapeutic potential of compounds from natural sources, Callistephus chinensis flowers (CCF) were tested for inhibition of α-glucosidase, and acarboes was used as the positive control. The 70 % ethanol extract of CCF exhibited significant α-glucosidase inhibitory activities with IC50 value of 8.14 μg/ml. The stepwise polarity fractions of CCF were tested further for in vitro inhibition of α-glucosidase. The ethyl acetate (EtOAc) fraction exhibited the most significant inhibitory activity. Eight pure compounds, apigenin, apigenin-7-O-β-D- glucoside, kaempferol, hyperin, naringenin, quercetin, luteolin, and kaempferol-7-O-β-D- glucoside, were isolated (using enzyme assay-guide fractionation method) from the EtOAc fraction. Among these, quercetin was the most active one (IC50 values 2.04 μg/ml), and it appears that the inhibiting percentages are close to acarbose (IC50 values 2.24 μg/ml), the positive control, on α-glucosidase inhibition. HPLC/UV analysis indicated that the major components of CCF are kaempferol, hyperin and quercetin. The presented results revealed that CCF containing these eight flavonoids could be a useful natural source in the development of a novel α-glucosidase inhibitory agent against diabetic complications. PMID:27298611

  13. DC-159a Shows Inhibitory Activity against DNA Gyrases of Mycobacterium leprae

    PubMed Central

    Yamaguchi, Tomoyuki; Yokoyama, Kazumasa; Nakajima, Chie

    2016-01-01

    Background Fluoroquinolones are a class of antibacterial agents used for leprosy treatment. Some new fluoroquinolones have been attracting interest due to their remarkable potency that is reportedly better than that of ofloxacin, the fluoroquinolone currently recommended for treatment of leprosy. For example, DC-159a, a recently developed 8-methoxy fluoroquinolone, has been found to be highly potent against various bacterial species. Nonetheless, the efficacy of DC-159a against Mycobacterium leprae is yet to be examined. Methodology/Principal Findings To gather data that can support highly effective fluoroquinolones as candidates for new remedies for leprosy treatment, we conducted in vitro assays to assess and compare the inhibitory activities of DC-159a and two fluoroquinolones that are already known to be more effective against M. leprae than ofloxacin. The fluoroquinolone-inhibited DNA supercoiling assay using recombinant DNA gyrases of wild type and ofloxacin-resistant M. leprae revealed that inhibitory activities of DC-159a and sitafloxacin were at most 9.8- and 11.9-fold higher than moxifloxacin. Also the fluoroquinolone–mediated cleavage assay showed that potencies of those drugs were at most 13.5- and 9.8-fold higher than moxifloxacin. In addition, these two drugs retained their inhibitory activities even against DNA gyrases of ofloxacin-resistant M. leprae. Conclusions/Significance The results indicated that DC-159a and sitafloxacin are more effective against wild type and mutant M. leprae DNA gyrases than moxifloxacin, suggesting that these antibacterial drugs can be good candidates that may supersede current fluoroquinolone remedies. DC-159a in particular is very promising because it is classified in a subgroup of fluoroquinolones that is known to be less likely to cause adverse effects. Our results implied that DC-159a is well worth further investigation to ascertain its in vivo effectiveness and clinical safety for humans. PMID:27681932

  14. Nitric oxide inhibitory activity of monogalactosylmonoacylglycerols from a freshwater microalgae Chlorella sorokiniana.

    PubMed

    Banskota, Arjun H; Stefanova, Roumiana; Gallant, Pamela; Osborne, Jane A; Melanson, Ronald; O'Leary, Stephen J B

    2013-01-01

    Chemical investigation of the freshwater microalgae Chlorella sorokiniana led to the isolation of a new monogalactosylmonoacylglycerol, namely, (2S)-1-O-(7Z,10Z-hexadecadienoyl)-3-O-β-D-galactopyranosylglycerol (1) together with a known glycolipid (2S)-1-O-(7Z,10Z,13Z-hexadecatrienoyl)-3-O-β-D-galactopyranosylglycerol (2). Both monogalactosylmonoacylglycerols showed dose-dependent nitric oxide (NO) inhibitory activity against lipopolysaccharide-induced NO production in RAW264.7 macrophage cells suggesting their possible use as anti-inflammatory agents. PMID:22703524

  15. Four New Flavonoids with α-Glucosidase Inhibitory Activities from Morus alba var. tatarica.

    PubMed

    Zhang, Ya-Long; Luo, Jian-Guang; Wan, Chuan-Xing; Zhou, Zhong-Bo; Kong, Ling-Yi

    2015-11-01

    Four new flavonoids, mortatarins A-D (1-4, resp.), along with eight known flavonoids (5-12) were isolated from the root bark of Morus alba var. tatarica. Their structures were established on the basis of spectroscopic data analysis, and the absolute configuration of 4 was determined by analysis of its CD spectrum. All isolates were tested for inhibitory activities against α-glucosidase. Compounds 4, 7, and 8 exhibited a significant degree of inhibition with IC50 values of 5.0 ± 0.3, 7.5 ± 0.5, and 5.9 ± 0.2 μM, respectively. PMID:26567954

  16. Synthesis and p38 Inhibitory Activity of Some Novel Substituted N,N'-Diarylurea Derivatives.

    PubMed

    Zhu, Dianxi; Xing, Qifeng; Cao, Ruiyuan; Zhao, Dongmei; Zhong, Wu

    2016-01-01

    We have identified a novel series of substituted N,N'-diarylurea p38α inhibitors. The inhibitory activity of the target compounds against the enzyme p38α, MAPKAPK2 in BHK cells, TNF-α release in LPS-stimulated THP-1 cells and p38α binding experiments were tested. Among these compounds, 25a inhibited the p38α enzyme with an IC50 value of 0.47 nM and a KD value of 1.54 × 10(-8) and appears to be the most promising one in the series. PMID:27223276

  17. Flavonol dimers from callus cultures of Dysosma versipellis and their in vitro neuraminidase inhibitory activities.

    PubMed

    Chen, Ridao; Duan, Ruigang; Wei, Yannan; Zou, Jianhua; Li, Junwei; Liu, Xiaoyue; Wang, Haiyan; Guo, Ying; Li, Qiuhong; Dai, Jungui

    2015-12-01

    A chemical investigation of callus cultures of Dysosma versipellis led to the isolation of five new flavonol dimers, dysoverines A-E (1-5), together with 12 known compounds (6-17). The structures of new compounds were determined by the extensive spectroscopic data analyses. The biosynthetic pathway of the new compounds was proposed to involve O-methylation, prenylation, and Diels-Alder cycloaddition, which successively occurred in cultured plant cells. Compounds 1-17 exhibited in vitro neuraminidase inhibitory activities with the IC50 values of 31.0-93.9μM. PMID:26481138

  18. Four New Flavonoids with α-Glucosidase Inhibitory Activities from Morus alba var. tatarica.

    PubMed

    Zhang, Ya-Long; Luo, Jian-Guang; Wan, Chuan-Xing; Zhou, Zhong-Bo; Kong, Ling-Yi

    2015-11-01

    Four new flavonoids, mortatarins A-D (1-4, resp.), along with eight known flavonoids (5-12) were isolated from the root bark of Morus alba var. tatarica. Their structures were established on the basis of spectroscopic data analysis, and the absolute configuration of 4 was determined by analysis of its CD spectrum. All isolates were tested for inhibitory activities against α-glucosidase. Compounds 4, 7, and 8 exhibited a significant degree of inhibition with IC50 values of 5.0 ± 0.3, 7.5 ± 0.5, and 5.9 ± 0.2 μM, respectively.

  19. The inhibitory effect of metals and other ions on acid phosphatase activity from Vigna aconitifolia seeds.

    PubMed

    Srivastava, Pramod Kumar; Anand, Asha

    2015-01-01

    Sensitivity of acid phosphatase from Vigna aconitifolia seeds to metal ions, fluoride, and phosphate was examined. All the effectors had different degree of inhibitory effect on the enzyme. Among metal ions, molybdate and ferric ion were observed to be most potent inhibitors and both exhibited mixed type of inhibition. Acid phosphatase activity was inhibited by Cu2+ in a noncompetitive manner. Zn and Mn showed mild inhibition on the enzyme activity. Inhibition kinetics analysis explored molybdate as a potent inhibitor for acid phosphatase in comparison with other effectors used in this study. Fluoride was the next most strong inhibitor for the enzyme activity, and caused a mixed type of inhibition. Phosphate inhibited the enzyme competitively, which demonstrates that inhibition due to phosphate is one of the regulatory factors for enzyme activity.

  20. Evaluation of antioxidant activity and inhibitory effect on nitric oxide production of some common vegetables.

    PubMed

    Bor, Jung-Yi; Chen, Hui-Yin; Yen, Gow-Chin

    2006-03-01

    The objectives of this study were to study the antioxidant activities and nitric oxide (NO) scavenging effects of vegetables in vitro systems and to study the inhibitory effects of vegetables on the NO production and NO-induced DNA damage in RAW 264.7 macrophage. The results indicated that water extracts from Indian lotus, Jew's ear, shiitake, eggplant, and winter mushroom showed stronger antioxidant activity and free-radical-scavenging ability than that of other vegetable extracts. The scavenging effects of vegetable extracts on NO derived from sodium nitroprusside (SNP) were in decreasing order of water spinach > Indian lotus > eggplant and garland chrysanthemum. In the macrophage model system, the water extracts from fresh daylily flower, sponge gourd, pea sprout, and eggplant exhibited over 80% inhibition on NO generation stimulated by lipopolysaccharide. The extract from fresh daylily flower that expressed the strongest inhibition on NO production was attributed to the ability to reduce the inducible nitric oxide synthase (iNOS) induction. However, the extracts from pea sprout and eggplant suppressed the NO production by scavenging on NO and inactivating toward iNOS enzyme. In addition, the water extracts from fresh daylily flower, sponge gourd, pea sprout, and eggplant also showed over 40% inhibitory effect on DNA damage induced by SNP in RAW 264.7 macrophage. The data also indicated that eggplant and pea sprout extracts contained higher total phenolic compounds, anthocyanins, and ascorbic acids and appeared to be responsible for their antioxidant activities and scavenging effects on NO derived from SNP. PMID:16506819

  1. Hypocholesterolemic Effect and In Vitro Pancreatic Lipase Inhibitory Activity of an Opuntia ficus-indica Extract

    PubMed Central

    Flores-Fernandez, Jose Miguel; Fernandez-Flores, Ofelia; Gutierrez-Mercado, Yanet; Carmona-de la Luz, Joel; Sandoval-Salas, Fabiola; Mendez-Carreto, Carlos

    2015-01-01

    Cholesterol control is fundamental for prevention of cardiovascular disorders. In this work, the hypocholesterolemic activity of an aqueous Opuntia ficus-indica extract (AOE) was tested in triton-induced mice. The inhibitory activity on pancreatic lipase enzyme was evaluated in vitro by the same extract. Furthermore, polyphenol content of the extract was evaluated. Hypercholesterolemia was induced in three groups of mice by intraperitoneal administration of Triton WR-1339. After induction of hypercholesterolemia, the groups were treated with an AOE (500 mg/kg) and saline solution and the positive control group with orlistat, respectively. Cholesterol levels were measured 24 h later in peripheral blood. The levels of blood cholesterol after administration of AOE significantly decreased compared to negative control. The inhibitory activity of AOE on pancreatic lipase enzyme was evaluated at concentrations from 60 to 1000 μg/mL. The AOE inhibited the pancreatic lipase with an IC50 = 588.5 μg/mL. The AOE had a high content of polyphenolic compounds. These results show that AOE is able to prevent hypercholesterolemia by pancreatic lipase inhibition, in part due to its polyphenolic compounds. PMID:26078966

  2. Inhibitory effects of fruit juices on cytochrome P450 2C9 activity in vitro.

    PubMed

    Hidaka, Muneaki; Nagata, Masashi; Kawano, Yohei; Sekiya, Hiroshi; Kai, Hirofumi; Yamasaki, Keishi; Okumura, Manabu; Arimori, Kazuhiko

    2008-02-01

    There is limited information on the effect of fruits on human cytochrome P450 (CYP) 2C9 activity. The objective of this study was to determine the effect of fruit juice on CYP2C9-mediated drug metabolism. Nine citrus fruits and eight tropical fruits were chosen. We investigated effects of the fruits on diclofenac 4'-hydroxylation and tolbutamide hydroxylation by human liver microsomes. Among the fruits, pineapple juice showed potent inhibition of CYP2C9 activity. The addition of 25 microl (5.0% v/v) of pineapple juice resulted in almost complete inhibition. Next we examined the inhibitory effect of bromelain, a cysteine protease in pineapple. Bromelain also strongly inhibited CYP2C9 activity. In addition, E-64, a cysteine protease inhibitor, almost entirely blocked inhibition by pineapple juice and bromelain. Thus we found that pineapple juice was a potent inhibitor of CYP2C9, and that the inhibitory effect might be due to the bromelain contained in pineapple.

  3. Superoxide radicals scavenging and xanthine oxidase inhibitory activity of magnesium lithospermate B from Salvia miltiorrhiza.

    PubMed

    Liu, Xiaoyu; Chen, Ruohua; Shang, Yanjun; Jiao, Binghua; Huang, Caiguo

    2009-06-01

    In this study we investigated the superoxide radicals scavenging effect and xanthine oxidase inhibitory activity by magnesium lithospermate B, which was originally isolated from the roots of Salvia miltiorrhiza (also named Danshen or Dansham), an important herb in Oriental medicine. Superoxide radicals were generated both in beta-NADH/PMS system and xanthine/ xanthine oxidase system. Magnesium lithospermate B significantly inhibited the reduction of NBT induced by superoxide radicals with an IC(50) of 29.8 microg/mL and 4.06 microg/mL respectively in the two systems. Further study suggested that magnesium lithospermate B can directly inhibit xanthine oxidase and exhibits competitive inhibition. Magnesium lithospermate B was also found to have the hypouricemic activity in vivo against potassium oxonate-induced hyperuricaemia in mice. After oral administration of magnesium lithospermate B at doses of 10, 20 and 30 mg/kg, there was a significant decrease in the serum urate level when compared to the hyperuricemia control. In addition, magnesium lithospermate B significantly protected HL-60 cells from superoxide radicals-induced apoptosis in the xanthine/ xanthine oxidase reactions. This study provided evidence that magnesium lithospermate B exhibits direct superoxide radicals scavenging and xanthine oxidase inhibitory activity.

  4. Neuraminidase inhibitory activities of quaternary isoquinoline alkaloids from Corydalis turtschaninovii rhizome.

    PubMed

    Kim, Jang Hoon; Ryu, Young Bae; Lee, Woo Song; Kim, Young Ho

    2014-11-01

    Clostridium perfringens is a Gram-positive spore-forming bacterium that causes food poisoning. The neuraminidase (NA) protein of C. perfringens plays a pivotal role in bacterial proliferation and is considered a novel antibacterial drug target. Based on screens for novel NA inhibitors, a 95% EtOH extract of Corydalis turtschaninovii rhizome showed NA inhibitory activity (68% at 30 μg/ml), which resulted in the isolation of 10 isoquinoline alkaloids; namely, palmatine (1), berberine (2), coptisine (3), pseudodehydrocorydaline (4), jatrorrhizine (5), dehydrocorybulbine (6), pseudocoptisine (7), glaucine (8), corydaline (9) and tetrahydrocoptisine (10). Interestingly, seven quaternary isoquinoline alkaloids 1-7 (IC50 = 12.8 ± 1.5 to 65.2 ± 4.5 μM) showed stronger NA inhibitory activity than the tertiary alkaloids 8-10. In addition, highly active compounds 1 and 2 showed reversible non-competitive behavior based on a kinetic study. Molecular docking simulations using the Autodock 4.2 software increased our understanding of receptor-ligand binding of these compounds. In addition, we demonstrated that compounds 1 and 2 suppressed bacterial growth.

  5. Spectroscopic studies on the inhibitory effects of ionic liquids on lipase activity

    NASA Astrophysics Data System (ADS)

    Fan, Yunchang; Dong, Xing; Li, Xiaojing; Zhong, Yingying; Kong, Jichuan; Hua, Shaofeng; Miao, Juan; Li, Yan

    2016-04-01

    The effects of ionic liquids (ILs) on the lipase activity were studied by UV-Vis spectroscopy and the IL-lipase interaction mechanism at the molecular level was investigated by fluorescence technique. Experimental results indicated that the lipase activity was inhibited by ILs and the degree of inhibition highly depended on the chemical structures of ILs. The inhibitory ability of the Cl-- and Br--based ILs increased with increasing the alkyl chain length in the IL cation. Thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS) were obtained by analyzing the fluorescence behavior of lipase with the addition of ILs. Both ΔH and ΔS were positive suggesting hydrophobicity was the major driven force for the Cl-- and Br--based ILs. For the BF4--, CF3SO3--, ClO4-- and N(CN)2--based ILs, hydrogen bonding was the main driven force. For a more comprehensive understanding of the effects of ILs on lipase activity, the roles of hydrophobicity and hydrogen bonding must be considered simultaneously. A regression-based equation was developed to describe the relationship of the inhibitory ability of ILs and their hydrophobicity and hydrogen bonding ability.

  6. Spectroscopic studies on the inhibitory effects of ionic liquids on lipase activity.

    PubMed

    Fan, Yunchang; Dong, Xing; Li, Xiaojing; Zhong, Yingying; Kong, Jichuan; Hua, Shaofeng; Miao, Juan; Li, Yan

    2016-04-15

    The effects of ionic liquids (ILs) on the lipase activity were studied by UV-Vis spectroscopy and the IL-lipase interaction mechanism at the molecular level was investigated by fluorescence technique. Experimental results indicated that the lipase activity was inhibited by ILs and the degree of inhibition highly depended on the chemical structures of ILs. The inhibitory ability of the Cl(-)- and Br(-)-based ILs increased with increasing the alkyl chain length in the IL cation. Thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS) were obtained by analyzing the fluorescence behavior of lipase with the addition of ILs. Both ΔH and ΔS were positive suggesting hydrophobicity was the major driven force for the Cl(-)- and Br(-)-based ILs. For the BF4(-)-, CF3SO3(-)-, ClO4(-)- and N(CN)2(-)-based ILs, hydrogen bonding was the main driven force. For a more comprehensive understanding of the effects of ILs on lipase activity, the roles of hydrophobicity and hydrogen bonding must be considered simultaneously. A regression-based equation was developed to describe the relationship of the inhibitory ability of ILs and their hydrophobicity and hydrogen bonding ability. PMID:26836454

  7. Acetylcholinesterase inhibitory activity of Thai traditional nootropic remedy and its herbal ingredients.

    PubMed

    Tappayuthpijarn, Pimolvan; Itharat, Arunporn; Makchuchit, Sunita

    2011-12-01

    The incidence of Alzheimer disease (AD) is increasing every year in accordance with the increasing of elderly population and could pose significant health problems in the future. The use of medicinal plants as an alternative prevention or even for a possible treatment of the AD is, therefore, becoming an interesting research issue. Acetylcholinesterase (AChE) inhibitors are well-known drugs commonly used in the treatment of AD. The aim of the present study was to screen for AChE inhibitory activity of the Thai traditional nootropic recipe and its herbal ingredients. The results showed that ethanolic extracts of four out of twenty-five herbs i.e. Stephania pierrei Diels. Kaempfera parviflora Wall. ex Baker, Stephania venosa (Blume) Spreng, Piper nigrum L at 0.1 mg/mL showed % AChE inhibition of 89, 64, 59, 50; the IC50 were 6, 21, 29, 30 microg/mL respectively. The other herbs as well as combination of the whole recipe had no synergistic inhibitory effect on AChE activity. However some plants revealed antioxidant activity. More research should have be performed on this local wisdom remedy to verify the uses in scientific term. PMID:22619927

  8. Hypocholesterolemic Effect and In Vitro Pancreatic Lipase Inhibitory Activity of an Opuntia ficus-indica Extract.

    PubMed

    Padilla-Camberos, Eduardo; Flores-Fernandez, Jose Miguel; Fernandez-Flores, Ofelia; Gutierrez-Mercado, Yanet; Carmona-de la Luz, Joel; Sandoval-Salas, Fabiola; Mendez-Carreto, Carlos; Allen, Kirk

    2015-01-01

    Cholesterol control is fundamental for prevention of cardiovascular disorders. In this work, the hypocholesterolemic activity of an aqueous Opuntia ficus-indica extract (AOE) was tested in triton-induced mice. The inhibitory activity on pancreatic lipase enzyme was evaluated in vitro by the same extract. Furthermore, polyphenol content of the extract was evaluated. Hypercholesterolemia was induced in three groups of mice by intraperitoneal administration of Triton WR-1339. After induction of hypercholesterolemia, the groups were treated with an AOE (500 mg/kg) and saline solution and the positive control group with orlistat, respectively. Cholesterol levels were measured 24 h later in peripheral blood. The levels of blood cholesterol after administration of AOE significantly decreased compared to negative control. The inhibitory activity of AOE on pancreatic lipase enzyme was evaluated at concentrations from 60 to 1000 μg/mL. The AOE inhibited the pancreatic lipase with an IC50 = 588.5 μg/mL. The AOE had a high content of polyphenolic compounds. These results show that AOE is able to prevent hypercholesterolemia by pancreatic lipase inhibition, in part due to its polyphenolic compounds.

  9. The inhibitory activity of pomelo essential oil on the bacterial biofilms development on soft contact lenses.

    PubMed

    Saviuc, Crina; Dascălu, Luminita; Chifiriuc, Mariana Carmen; Rădulescu, Valeria; Oprea, Eliza; Popa, Marcela; Hristu, Radu; Stanciu, George; Lazăr, Veronica

    2010-01-01

    The aim of present study was to investigate the microbial colonization of worn contact lenses (CLs) and to evaluate the inhibitory effect of pomelo (Citrus maxima) peels essential oil on the biofilm development on unworn CLs. The essential oil was isolated by steam distillation and analyzed by gas chromatography coupled with mass spectrometry, twenty compounds being isolated. The antimicrobial activity of pomelo oil was tested against S. epidermidis and P. aeruginosa strains, known for their ability to develop biofilms on prosthetic devices, by qualitative screening methods and quantitative assay of the minimal inhibitory concentrations (MIC) in order to evaluate the antibiofilm activity. Our study revealed that all worn CLs where 100% colonized by staphylococci and Enterobacteriaceae strains. The pomelo essential oil inhibited the development of bacterial biofilms formed by Gram-positive and Gram-negative microorganisms on soft CLs, its antibiofilm activity being specific and dependent on different physical parameters (contact time and temperature). The architecture of bacterial biofilms developed on soft contact lenses was analyzed using confocal scanning laser microscopy (CSLM). PMID:21434591

  10. Oleanane-type triterpenoids of Aceriphyllum rossii and their diacylglycerol acyltransferase-inhibitory activity.

    PubMed

    Seo, Jee-Hee; Kim, Mun-Ock; Han, Ah-Reum; Kwon, Eun-Bin; Kang, Myung Ji; Cho, Sungchan; Moon, Dong-Oh; Noh, Jung-Ran; Lee, Chul-Ho; Kim, Young-Soo; Lee, Hyun-Sun

    2015-02-01

    Six known triterpenoid compounds, 3-oxoolean-12-en-27-oic acid (1), gypsogenic acid (2), 3α-hydroxyolean-12-en-27-oic acid (3), 3β-hydroxyolean-12-en-27-oic acid (4), aceriphyllic acid A (5), and oleanolic acid (6), were isolated from the roots of Aceriphyllum rossii. Their chemical structures were determined by comparison with available (1)H-NMR and (13)C-NMR data on known compounds. All the isolated compounds were evaluated for inhibitory activity against human diacylglycerol acyltransferases 1 and 2. Most of the isolates exhibited a better inhibitory activity against diacylglycerol acyltransferase 2 (IC50: 11.6-44.2 µM) than against diacylglycerol acyltransferase 1 (IC50: 22.7-119.5 µM). In particular, compounds 1 and 5 showed strong inhibition efficacy towards diacylglycerol acyltransferases 1 and 2, and appeared to act competitively against oleoyl-CoA in vitro. The results also indicated that both compounds reduced newly synthesized triacylglycerol in HuTu80 and HepG2 cells. Oral administration of compound 1 significantly reduced postprandial triacylglycerol in mice following an oral lipid challenge. In conclusion, the current study indicates that compound 1 suppresses both de novo triacylglycerol biosynthesis and resynthesis through the inhibition of diacylglycerol acyltransferase activity, and therefore may be a useful agent for treating diseases associated with a high triacylglycerol level.

  11. Mutation at Glu23 eliminates the neuron growth inhibitory activity of human metallothionein-3

    SciTech Connect

    Ding Zhichun; Teng Xinchen; Cai Bin; Wang Hui; Zheng Qi; Wang Yang; Zhou Guoming; Zhang Mingjie; Wu Houming; Sun Hongzhe . E-mail: hsun@hku.hk; Huang Zhongxian . E-mail: zxhuang@fudan.edu.cn

    2006-10-20

    Human metallothionein-3 (hMT3), first isolated and identified as a neuronal growth inhibitory factor (GIF), is a metalloprotein expressed predominantly in brain. However, untill now, the exact mechanism of the bioactivity of hMT3 is still unknown. In order to study the influence of acid-base catalysis on S-nitrosylation of hMT3, we constructed the E23K mutant of hMT3. During the course of bioassay, we found out unexpectedly that mutation at E23 of hMT3 eliminates the neuronal growth inhibitory activity completely. To the best of our knowledge, it is First report that other residues, besides the TCPCP motif, in the {beta}-domain can alter the bioactivity of hMT3. In order to figure out the causes for the loss of bioactivity of the E23K mutant, the biochemical properties were characterized by UV-vis spectroscopy, CD spectroscopy, pH titration, DTNB reaction, EDTA reaction, and SNOC reaction. All data demonstrated that stability of the metal-thiolate cluster and overall structure of the E23K mutant were not altered too much. However, the reaction of the E23K mutant with SNOC exhibited biphasic kinetics and the mutant protein released zinc ions much faster than hMT3 in the initial step, while hMT3 exhibited single kinetic process. The 2D [{sup 1}H-{sup 15}N] HSQC was also employed to characterize structural changes during the reaction of hMT3 with varying mounts of nitric oxide. It was shown that the resonance of Glu23 disappeared at a molar ratio of NO to protein of 4. Based on these results, we suggest that mutation at Glu23 may alter the NO metabolism and/or affect zinc homeostasis in brain, thus altering the neuronal growth inhibitory activity.

  12. Enzyme Inhibitory Properties, Antioxidant Activities, and Phytochemical Profile of Three Medicinal Plants from Turkey

    PubMed Central

    Zengin, Gokhan; Guler, Gokalp Ozmen; Aktumsek, Abdurrahman; Ceylan, Ramazan; Picot, Carene Marie Nancy; Mahomoodally, M. Fawzi

    2015-01-01

    We aimed to investigate the inhibitory potential of three medicinal plants (Hedysarum varium, Onobrychis hypargyrea, and Vicia truncatula) from Turkey against key enzymes involved in human pathologies, namely, diabetes (α-amylase and α-glucosidase), neurodegenerative disorders (tyrosinase, acetylcholinesterase, and butyrylcholinesterase), and hyperpigmentation (tyrosinase). The antioxidant potential, phenolic and flavonoid content of ethyl acetate, and methanolic and aqueous extracts were investigated using in vitro assays. The total antioxidant capacity (TAC), β-carotene/linoleic acid bleaching activity, 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH•), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+), cupric ion reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), and metal chelating activity on ferrous ions were used to evaluate the antioxidant capabilities of the extracts. The half-maximal inhibitory concentrations (IC50) of the extracts on cholinesterase, tyrosinase, and α-amylase were significantly higher than the references, galantamine, kojic acid, and acarbose, respectively. The half-maximal effective concentrations (EC50) of the extracts on TAC, CUPRAC, and FRAP were significantly higher than trolox. The phenol and flavonoid contents of the plant extracts were in the range 20.90 ± 0.190–83.25 ± 0.914 mg gallic acid equivalent/g extract and 1.45 ± 0.200–39.71 ± 0.092 mg rutin equivalent/g extract, respectively. The plants were found to possess moderate antioxidant capacities and interesting inhibitory action against key enzymes. PMID:26798334

  13. Enzyme Inhibitory Properties, Antioxidant Activities, and Phytochemical Profile of Three Medicinal Plants from Turkey.

    PubMed

    Zengin, Gokhan; Guler, Gokalp Ozmen; Aktumsek, Abdurrahman; Ceylan, Ramazan; Picot, Carene Marie Nancy; Mahomoodally, M Fawzi

    2015-01-01

    We aimed to investigate the inhibitory potential of three medicinal plants (Hedysarum varium, Onobrychis hypargyrea, and Vicia truncatula) from Turkey against key enzymes involved in human pathologies, namely, diabetes (α-amylase and α-glucosidase), neurodegenerative disorders (tyrosinase, acetylcholinesterase, and butyrylcholinesterase), and hyperpigmentation (tyrosinase). The antioxidant potential, phenolic and flavonoid content of ethyl acetate, and methanolic and aqueous extracts were investigated using in vitro assays. The total antioxidant capacity (TAC), β-carotene/linoleic acid bleaching activity, 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH(•)), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(•+)), cupric ion reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), and metal chelating activity on ferrous ions were used to evaluate the antioxidant capabilities of the extracts. The half-maximal inhibitory concentrations (IC50) of the extracts on cholinesterase, tyrosinase, and α-amylase were significantly higher than the references, galantamine, kojic acid, and acarbose, respectively. The half-maximal effective concentrations (EC50) of the extracts on TAC, CUPRAC, and FRAP were significantly higher than trolox. The phenol and flavonoid contents of the plant extracts were in the range 20.90 ± 0.190-83.25 ± 0.914 mg gallic acid equivalent/g extract and 1.45 ± 0.200-39.71 ± 0.092 mg rutin equivalent/g extract, respectively. The plants were found to possess moderate antioxidant capacities and interesting inhibitory action against key enzymes. PMID:26798334

  14. Quassinoids from the stems of Picrasma quassioides and their cytotoxic and NO production-inhibitory activities.

    PubMed

    Xu, Jian; Xiao, Di; Song, Wei-Wu; Chen, Lei; Liu, Wen-Yuan; Xie, Ning; Feng, Feng; Qu, Wei

    2016-04-01

    Three new C20 quassinoids nigakilactone P (1), picraqualide F (2), nigakilactone Q (3), along with eight known quassinoids (4-11), were isolated from the 95% EtOH extract of the stems of Picrasma quassioides. The structures of the new compounds were elucidated by means of HRESIMS and different NMR techniques. Assignments of relative and absolute configurations for these compounds were achieved on the basis of ROESY spectra and quantum chemical ECD calculation. In vitro activity assays, none of the compounds showed cytotoxic (IC50>50 μM) and NO production-inhibitory activities (IC50>30 μM), and the structure-activity relationships of quassinoids were summarized. In addition, the chemotaxonomic significance of the isolated compounds was also discussed.

  15. Inhibitory effect of pinaverium bromide on gastrointestinal contractile activity in conscious dogs.

    PubMed

    Itoh, Z; Takahashi, I

    1981-01-01

    The inhibitory effect of 4-(6-bromoveratryl)-4-(2-[2-(6,6-dimethyl-2-norpinyl)-ethoxy]-ethyl)-morpholinium hydroxide (pinaverium bromide), a quaternary ammonium derivative, on the contractile activity of the gastrointestinal tract from the stomach to the colon was investigated in six conscious dogs. Gastrointestinal motor activity was monitored by means of chronically implanted force transducers. Pinaverium bromide was continuously administered i.v. for 30 min in doses of 10 and 20 mg/kg/h during both the digestive and interdigestive states. It was found that pinaverium bromide strongly inhibited gastrointestinal contractile activity during both the digestive and interdigestive states; contractions in the stomach were most strongly inhibited; however, those in the small and large bowels were also significantly inhibited. No significant side effects in the circulatory and respiratory systems and the gastrointestinal tract such as nausea, vomiting or diarrhea were observed during and after the infusion of this agent. PMID:7197953

  16. Development of cyclobutene- and cyclobutane-functionalized fatty acids with inhibitory activity against Mycobacterium tuberculosis

    PubMed Central

    Sittiwong, Wantanee; Zinniel, Denise K.; Fenton, Robert J.; Marshall, Darrel; Story, Courtney B.; Kim, Bohkyung; Lee, Ji-Young; Powers, Robert; Barletta, Raúl G.

    2014-01-01

    Eleven fatty acid analogs incorporating four-membered carbocycles (cyclobutenes, cyclobutanes, cyclobutanones, and cyclobutanols) were investigated for the ability to inhibit growth of Mycobacterium smegmatis (Msm) and Mycobacterium tuberculosis (Mtb). A number of the analogs displayed inhibitory activity against both mycobacterial species in minimal media. Several of the molecules displayed potent levels of inhibition against Mtb with MIC values equal to or below those obtained with the anti-tuberculosis drugs D-cycloserine and isoniazid. In contrast, two of the analogs displaying the greatest activity against Mtb failed to inhibit E. coli growth under either set of conditions. Thus, the active molecules identified here (1, 2, 6, and 8) may provide the basis for development of anti-mycobacterial agents against Mtb. PMID:24902951

  17. In vitro inhibitory activity of essential oil vapors against Ascosphaera apis.

    PubMed

    Kloucek, Pavel; Smid, Jakub; Flesar, Jaroslav; Havlik, Jaroslav; Titera, Dalibor; Rada, Vojtech; Drabek, Ondrej; Kokoska, Ladislav

    2012-02-01

    This work evaluates the in vitro inhibitory activity of 70 essential oils (EOs) in the vapor phase for the control of Chalkbrood disease caused by Ascosphaera apis Maassen ex Claussen (Olive et Spiltoir). Two wild strains isolated from infected honey bee colonies together with one standard collection strain were tested by the microatmosphere method. From 70 EOs, 39 exhibited an antifungal effect against A. apis standard and wild strains. The greatest antifungal action was observed for EO vapors from Armoracia rusticana, followed by Thymus vulgaris, Cymbopogon flexosus, Origanum vulgare and Allium sativum. An investigation of chemical composition by GC-MS revealed, that the most active EOs contained allyl isothiocyanate, citral, carvacrol and diallyl sulfides as the main constituents. The chemical composition plays a key role, as activities of different EOs from the same botanical species were different according to their composition. PMID:22474973

  18. Inhibitory effect of plant Manilkara subsericea against biological activities of Lachesis muta snake venom.

    PubMed

    De Oliveira, Eduardo Coriolano; Fernandes, Caio Pinho; Sanchez, Eladio Flores; Rocha, Leandro; Fuly, André Lopes

    2014-01-01

    Snake venom is composed of a mixture of substances that caused in victims a variety of pathophysiological effects. Besides antivenom, literature has described plants able to inhibit injuries and lethal activities induced by snake venoms. This work describes the inhibitory potential of ethanol, hexane, ethyl acetate, or dichloromethane extracts and fractions from stem and leaves of Manilkara subsericea against in vivo (hemorrhagic and edema) and in vitro (clotting, hemolysis, and proteolysis) activities caused by Lachesis muta venom. All the tested activities were totally or at least partially reduced by M. subsericea. However, when L. muta venom was injected into mice 15 min first or after the materials, hemorrhage and edema were not inhibited. Thus, M. subsericea could be used as antivenom in snakebites of L. muta. And, this work also highlights Brazilian flora as a rich source of molecules with antivenom properties.

  19. Inhibitory Effect of Plant Manilkara subsericea against Biological Activities of Lachesis muta Snake Venom

    PubMed Central

    De Oliveira, Eduardo Coriolano; Fernandes, Caio Pinho; Sanchez, Eladio Flores; Fuly, André Lopes

    2014-01-01

    Snake venom is composed of a mixture of substances that caused in victims a variety of pathophysiological effects. Besides antivenom, literature has described plants able to inhibit injuries and lethal activities induced by snake venoms. This work describes the inhibitory potential of ethanol, hexane, ethyl acetate, or dichloromethane extracts and fractions from stem and leaves of Manilkara subsericea against in vivo (hemorrhagic and edema) and in vitro (clotting, hemolysis, and proteolysis) activities caused by Lachesis muta venom. All the tested activities were totally or at least partially reduced by M. subsericea. However, when L. muta venom was injected into mice 15 min first or after the materials, hemorrhage and edema were not inhibited. Thus, M. subsericea could be used as antivenom in snakebites of L. muta. And, this work also highlights Brazilian flora as a rich source of molecules with antivenom properties. PMID:24511532

  20. Data on synthesis of methylene bisphosphonates and screening of their inhibitory activity towards HIV reverse transcriptase.

    PubMed

    Yanvarev, D V; Korovina, A N; Usanov, N N; Khomich, O A; Vepsäläinen, J; Puljula, E; Kukhanova, M K; Kochetkov, S N

    2016-09-01

    Inorganic pyrophosphate (PPi) mimetics designed on a basis of methylenediphosphonic acid backbone are promising inhibitors of two key HIV replication enzymes, IN [1] and RT [2]. Herein, we present chemical synthesis of eleven methylenebisphosphonates (BPs) with their NMR and HRMS analysis synthesized via five different ways. Also, we present data on inhibition of HIV RT catalyzed phosphorolysis and polymerization by synthesized BPs using two methods based on denaturing urea PAGE. Tests were also performed for thymidine analogue mutations reverse transcriptase (TAM RT), which was expressed and purified for that. Structure-activity relationships and inhibitory activity data of synthesized BPs are presented in "Methylene bisphosphonates as the inhibitors of HIV RT phosphorolytic activity" [2]. PMID:27547792

  1. Quassinoids from the stems of Picrasma quassioides and their cytotoxic and NO production-inhibitory activities.

    PubMed

    Xu, Jian; Xiao, Di; Song, Wei-Wu; Chen, Lei; Liu, Wen-Yuan; Xie, Ning; Feng, Feng; Qu, Wei

    2016-04-01

    Three new C20 quassinoids nigakilactone P (1), picraqualide F (2), nigakilactone Q (3), along with eight known quassinoids (4-11), were isolated from the 95% EtOH extract of the stems of Picrasma quassioides. The structures of the new compounds were elucidated by means of HRESIMS and different NMR techniques. Assignments of relative and absolute configurations for these compounds were achieved on the basis of ROESY spectra and quantum chemical ECD calculation. In vitro activity assays, none of the compounds showed cytotoxic (IC50>50 μM) and NO production-inhibitory activities (IC50>30 μM), and the structure-activity relationships of quassinoids were summarized. In addition, the chemotaxonomic significance of the isolated compounds was also discussed. PMID:26851344

  2. Acid-sensing ion channels regulate spontaneous inhibitory activity in the hippocampus: possible implications for epilepsy.

    PubMed

    Ievglevskyi, O; Isaev, D; Netsyk, O; Romanov, A; Fedoriuk, M; Maximyuk, O; Isaeva, E; Akaike, N; Krishtal, O

    2016-08-01

    Acid-sensing ion channels (ASICs) play an important role in numerous functions in the central and peripheral nervous systems ranging from memory and emotions to pain. The data correspond to a recent notion that each neuron and many glial cells of the mammalian brain express at least one member of the ASIC family. However, the mechanisms underlying the involvement of ASICs in neuronal activity are poorly understood. However, there are two exceptions, namely, the straightforward role of ASICs in proton-based synaptic transmission in certain brain areas and the role of the Ca(2+)-permeable ASIC1a subtype in ischaemic cell death. Using a novel orthosteric ASIC antagonist, we have found that ASICs specifically control the frequency of spontaneous inhibitory synaptic activity in the hippocampus. Inhibition of ASICs leads to a strong increase in the frequency of spontaneous inhibitory postsynaptic currents. This effect is presynaptic because it is fully reproducible in single synaptic boutons attached to isolated hippocampal neurons. In concert with this observation, inhibition of the ASIC current diminishes epileptic discharges in a low Mg(2+) model of epilepsy in hippocampal slices and significantly reduces kainate-induced discharges in the hippocampus in vivo Our results reveal a significant novel role for ASICs.This article is part of the themed issue 'Evolution brings Ca(2+) and ATP together to control life and death'. PMID:27377725

  3. ACE-I Inhibitory Activity from Phaseolus lunatus and Phaseolus vulgaris Peptide Fractions Obtained by Ultrafiltration.

    PubMed

    Betancur-Ancona, David; Dávila-Ortiz, Gloria; Chel-Guerrero, Luis Antonio; Torruco-Uco, Juan Gabriel

    2015-11-01

    The involvement of angiotensin-I-converting enzyme (ACE-I) as one of the mechanisms controlling blood pressure is being studied to find alternative means of control of hypertension on human beings. On the market there are synthetic drugs that can control it, but these can cause undesirable health side effects. In this work was assessed the fractionation by ultrafiltration of the Lima bean (Phaseolus lunatus) and Jamapa bean (Phaseolus vulgaris), protein hydrolysates obtained with Alcalase(®) and Flavourzyme(®) on ACE-I inhibitory activity. Four membranes of different molecular cutoffs (10, 5, 3, and 1 kDa) were used. Fractions that had a higher inhibitory activity in both legumes were denominated as E (<1 kDa) with IC50 of 30.3 and 51.8 μg/mL values for the P. lunatus with Alcalase and Flavourzyme, respectively, and for the Phaseolus vulgaris with Alcalase and Flavourzyme with about 63.8 and 65.8 μg/mL values, respectively. The amino acid composition of these fractions showed residues in essential amino acids, which make a good source of energy and amino acids. On the other hand, the presence of hydrophobic amino acids such as V and P is a determining factor in the ACE-I inhibitor effect. The results suggest the possibility of obtaining and utilizing these peptide fractions in the development and innovation of a functional product that helps with treatment and/or prevention of hypertension.

  4. The effects of inhibitory control training for preschoolers on reasoning ability and neural activity.

    PubMed

    Liu, Qian; Zhu, Xinyi; Ziegler, Albert; Shi, Jiannong

    2015-09-23

    Inhibitory control (including response inhibition and interference control) develops rapidly during the preschool period and is important for early cognitive development. This study aimed to determine the training and transfer effects on response inhibition in young children. Children in the training group (N = 20; 12 boys, mean age 4.87 ± 0.26 years) played "Fruit Ninja" on a tablet computer for 15 min/day, 4 days/week, for 3 weeks. Children in the active control group (N = 20; 10 boys, mean age 4.88 ± 0.20 years) played a coloring game on a tablet computer for 10 min/day, 1-2 days/week, for 3 weeks. Several cognitive tasks (involving inhibitory control, working memory, and fluid intelligence) were used to evaluate the transfer effects, and electroencephalography (EEG) was performed during a go/no-go task. Progress on the trained game was significant, while performance on a reasoning task (Raven's Progressive Matrices) revealed a trend-level improvement from pre- to post-test. EEG indicated that the N2 effect of the go/no-go task was enhanced after training for girls. This study is the first to show that pure response inhibition training can potentially improve reasoning ability. Furthermore, gender differences in the training-induced changes in neural activity were found in preschoolers.

  5. Antioxidant activity and ACE-inhibitory of Class II hydrophobin from wild strain Trichoderma reesei.

    PubMed

    Khalesi, Mohammadreza; Jahanbani, Raheleh; Riveros-Galan, David; Sheikh-Hassani, Vahid; Sheikh-Zeinoddin, Mahmoud; Sahihi, Mehdi; Winterburn, James; Derdelinckx, Guy; Moosavi-Movahedi, Ali Akbar

    2016-10-01

    There are several possible uses of the Class II hydrophobin HFBII in clinical applications. To fully understand and exploit this potential however, the antioxidant activity and ACE-inhibitory potential of this protein need to be better understood and have not been previously reported. In this study, the Class II hydrophobin HFBII was produced by the cultivation of wild type Trichoderma reesei. The crude hydrophobin extract obtained from the fermentation process was purified using reversed-phase liquid chromatography and the identity of the purified HFBII verified by MALDI-TOF (molecular weight: 7.2kDa). Subsequently the antioxidant activities of different concentrations of HFBII (0.01-0.40mg/mL) were determined. The results show that for HFBII concentrations of 0.04mg/mL and upwards the protein significantly reduced the presence of ABTS(+) radicals in the medium, the IC50 value found to be 0.13mg/mL. Computational modeling highlighted the role of the amino acid residues located in the conserved and exposed hydrophobic patch on the surface of the HFBII molecule and the interactions with the aromatic rings of ABTS. The ACE-inhibitory effect of HFBII was found to occur from 0.5mg/mL and upwards, making the combination of HFBII with strong ACE-inhibitors attractive for use in the healthcare industry. PMID:27211298

  6. acetylcholinesterase inhibitory potential and insecticidal activity of an endophytic Alternaria sp. from Ricinus communis.

    PubMed

    Singh, Bahaderjeet; Thakur, Abhinay; Kaur, Sanehdeep; Chadha, B S; Kaur, Amarjeet

    2012-11-01

    Keeping in view the vast potential of endophytic fungi to produce bioactive molecules, this study aimed at isolating and screening endophytes for the production of acetylcholinesterase inhibitors. Fifty-four endophytic fungi were isolated from Ricinus communis and screened for their AChE inhibitory activity using Ellman's colorimetric assay method. Six isolates were found to possess AChE inhibitory activity with maximum inhibition of 78 % being evinced by culture Cas1 which was identified to be Alternaria sp. on the basis of molecular as well as microscopic methods. Optimization of inhibitor production was carried out using one factor at a time approach. Maximum production of inhibitor was obtained on potato dextrose broth after 10 days incubation. The IC(50) of the chloroform extract was observed to be 40 μg/ml. The extract was purified on silica gel and eluted stepwise with a gradient of chloroform/methanol. The insecticidal potential of the extract was evaluated by feeding the larvae of Spodoptera litura on diet containing varying concentrations of the extract. It was observed that with increase in the concentration of the extract, mortality of the larvae increased. The culture has the potential of being exploited in medicine as well as a biocontrol agent.

  7. Screening of α-Glucosidase Inhibitory Activity from Some Plants of Apocynaceae, Clusiaceae, Euphorbiaceae, and Rubiaceae

    PubMed Central

    Elya, Berna; Basah, Katrin; Mun'im, Abdul; Yuliastuti, Wulan; Bangun, Anastasia; Septiana, Eva Kurnia

    2012-01-01

    Diabetes mellitus (DM) is recognized as a serious global health problem that is characterized by high blood sugar levels. Type 2 DM is more common in diabetic populations. In this type of DM, inhibition of α-glucosidase is a useful treatment to delay the absorption of glucose after meals. As a megabiodiversity country, Indonesia still has a lot of potential unexploited forests to be developed as a medicine source, including as the α-glucosidase inhibitor. In this study, we determine the α-glucosidase inhibitory activity of 80% ethanol extracts of leaves and twigs of some plants from the Apocynaceae, Clusiaceae, Euphorbiaceae, and Rubiaceae. Inhibitory activity test of the α-glucosidase was performed in vitro using spectrophotometric methods. Compared with the control acarbose (IC50 117.20 μg/mL), thirty-seven samples of forty-five were shown to be more potent α-glucosidase inhibitors with IC50 values in the range 2.33–112.02 μg/mL. PMID:22187534

  8. Isolation of natural compounds from Phlomis stewartii showing α-glucosidase inhibitory activity.

    PubMed

    Jabeen, Bushra; Riaz, Naheed; Saleem, Muhammad; Naveed, Muhammad Akram; Ashraf, Muhammad; Alam, Umber; Rafiq, Hafiza Mehwish; Tareen, Rasool Bakhsh; Jabbar, Abdul

    2013-12-01

    Stewartiiside (1), a phenylethanoid glycoside and three 28-nortriterpenoids: stewertiisins A-C [(17R)-19(18→17)-abeo-3α,18β,23,24-tetrahydroxy-28-norolean-12-ene, 2; (17R)-19(18→17)-abeo-2α,16β,18β,23,24-pentahydroxy-28-norolean-12-en-3-one, 3; (17R)-19(18→17)-abeo-2α,3α,23,24-tetrahydroxy-28-noroleane-11,13-diene, 4] together with eight known compounds: lunariifolioside (5), notohamosin A (6), phlomispentanol (7), isorhamnetin 3-(6-p-coumaroyl)-β-D-glucopyranoside (8), tiliroside (9), caffeic acid (10), p-hydrxybenzoic acid (11) and oleanolic acid (12) were isolated from the ethyl acetate soluble fraction of the methanolic extract of whole plant of Phlomis stewartii. The structures of these isolates (1-12) were elucidated by the combination of 1D ((1)H and (13)C NMR), 2D (HMQC, HMBC COSY, NOESY) NMR spectroscopy and mass spectrometry (EIMS, HREIMS, FABMS, HRFABMS) and in comparison with literature data of related compounds. All the isolates (1-12) showed α-glucosidase inhibitory activity with IC50 values ranging between 14.5 and 355.4 μM, whereas, compounds 1, 5, 9 and 10 showed promising α-glucosidase inhibitory activity with IC50 values below 30 μM.

  9. Investigation of aromatase inhibitory activity of metal complexes of 8-hydroxyquinoline and uracil derivatives

    PubMed Central

    Prachayasittikul, Veda; Pingaew, Ratchanok; Nantasenamat, Chanin; Prachayasittikul, Supaluk; Ruchirawat, Somsak; Prachayasittikul, Virapong

    2014-01-01

    Purpose Estrogens play important roles in the pathogenesis and progression of breast cancer as well as estrogen-related diseases. Aromatase is a key enzyme in the rate-limiting step of estrogen production, in which its inhibition is one strategy for controlling estrogen levels to improve prognosis of estrogen-related cancers and diseases. Herein, a series of metal (Mn, Cu, and Ni) complexes of 8-hydroxyquinoline (8HQ) and uracil derivatives (4–9) were investigated for their aromatase inhibitory and cytotoxic activities. Methods The aromatase inhibition assay was performed according to a Gentest™ kit using CYP19 enzyme, wherein ketoconazole and letrozole were used as reference drugs. The cytotoxicity was tested on normal embryonic lung cells (MRC-5) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results Only Cu complexes (6 and 9) exhibited aromatase inhibitory effect with IC50 0.30 and 1.7 μM, respectively. Cytotoxicity test against MRC-5 cells showed that Mn and Cu complexes (5 and 6), as well as free ligand 8HQ, exhibited activity with IC50 range 0.74–6.27 μM. Conclusion Cu complexes (6 and 9) were found to act as a novel class of aromatase inhibitor. Our findings suggest that these 8HQ–Cu–uracil complexes are promising agents that could be potentially developed as a selective anticancer agent for breast cancer and other estrogen-related diseases. PMID:25152615

  10. Production of feline leukemia inhibitory factor with biological activity in Escherichia coli.

    PubMed

    Kanegi, R; Hatoya, S; Tsujimoto, Y; Takenaka, S; Nishimura, T; Wijewardana, V; Sugiura, K; Takahashi, M; Kawate, N; Tamada, H; Inaba, T

    2016-07-15

    Leukemia inhibitory factor (LIF) is a cytokine which is essential for oocyte and embryo development, embryonic stem cell, and induced pluripotent stem cell maintenance. Leukemia inhibitory factor improves the maturation of oocytes in the human and the mouse. However, feline LIF (fLIF) cloning and effects on oocytes during IVM have not been reported. Thus, we cloned complete cDNA of fLIF and examined its biological activity and effects on oocytes during IVM in the domestic cat. The aminoacid sequence of fLIF revealed a homology of 81% or 92% with that of mouse or human. The fLIF produced by pCold TF DNA in Escherichia coli was readily soluble and after purification showed bioactivity in maintaining the undifferentiated state of mouse embryonic stem cells and enhancing the proliferation of human erythrocyte leukemia cells. Furthermore, 10- and 100-ng/mL fLIF induced cumulus expansion with or without FSH and EGF (P < 0.05). The rate of metaphase II oocytes was also improved with 100-ng/mL fLIF (P < 0.05). We therefore confirmed the successful production for the first time of biologically active fLIF and revealed its effects on oocytes during IVM in the domestic cat. Feline LIF will further improve reproduction and stem cell research in the feline family. PMID:27020881

  11. The effects of inhibitory control training for preschoolers on reasoning ability and neural activity

    PubMed Central

    Liu, Qian; Zhu, Xinyi; Ziegler, Albert; Shi, Jiannong

    2015-01-01

    Inhibitory control (including response inhibition and interference control) develops rapidly during the preschool period and is important for early cognitive development. This study aimed to determine the training and transfer effects on response inhibition in young children. Children in the training group (N = 20; 12 boys, mean age 4.87 ± 0.26 years) played “Fruit Ninja” on a tablet computer for 15 min/day, 4 days/week, for 3 weeks. Children in the active control group (N = 20; 10 boys, mean age 4.88 ± 0.20 years) played a coloring game on a tablet computer for 10 min/day, 1–2 days/week, for 3 weeks. Several cognitive tasks (involving inhibitory control, working memory, and fluid intelligence) were used to evaluate the transfer effects, and electroencephalography (EEG) was performed during a go/no-go task. Progress on the trained game was significant, while performance on a reasoning task (Raven’s Progressive Matrices) revealed a trend-level improvement from pre- to post-test. EEG indicated that the N2 effect of the go/no-go task was enhanced after training for girls. This study is the first to show that pure response inhibition training can potentially improve reasoning ability. Furthermore, gender differences in the training-induced changes in neural activity were found in preschoolers. PMID:26395158

  12. The effects of inhibitory control training for preschoolers on reasoning ability and neural activity.

    PubMed

    Liu, Qian; Zhu, Xinyi; Ziegler, Albert; Shi, Jiannong

    2015-01-01

    Inhibitory control (including response inhibition and interference control) develops rapidly during the preschool period and is important for early cognitive development. This study aimed to determine the training and transfer effects on response inhibition in young children. Children in the training group (N = 20; 12 boys, mean age 4.87 ± 0.26 years) played "Fruit Ninja" on a tablet computer for 15 min/day, 4 days/week, for 3 weeks. Children in the active control group (N = 20; 10 boys, mean age 4.88 ± 0.20 years) played a coloring game on a tablet computer for 10 min/day, 1-2 days/week, for 3 weeks. Several cognitive tasks (involving inhibitory control, working memory, and fluid intelligence) were used to evaluate the transfer effects, and electroencephalography (EEG) was performed during a go/no-go task. Progress on the trained game was significant, while performance on a reasoning task (Raven's Progressive Matrices) revealed a trend-level improvement from pre- to post-test. EEG indicated that the N2 effect of the go/no-go task was enhanced after training for girls. This study is the first to show that pure response inhibition training can potentially improve reasoning ability. Furthermore, gender differences in the training-induced changes in neural activity were found in preschoolers. PMID:26395158

  13. QSAR prediction of HIV-1 protease inhibitory activities using docking derived molecular descriptors.

    PubMed

    Fatemi, Mohammad H; Heidari, Afsane; Gharaghani, Sajjad

    2015-03-21

    In this study, application of a new hybrid docking-quantitative structure activity relationship (QSAR) methodology to model and predict the HIV-1 protease inhibitory activities of a series of newly synthesized chemicals is reported. This hybrid docking-QSAR approach can provide valuable information about the most important chemical and structural features of the ligands that affect their inhibitory activities. Docking studies were used to find the actual conformations of chemicals in active site of HIV-1 protease. Then the molecular descriptors were calculated from these conformations. Multiple linear regression (MLR) and least square support vector machine (LS-SVM) were used as QSAR models, respectively. The obtained results reveal that statistical parameters of the LS-SVM model are better than the MLR model, which indicate that there are some non-linear relations between selected molecular descriptors and anti-HIV activities of interested chemicals. The correlation coefficient (R), root mean square error (RMSE) and average absolute error (AAE) for LS-SVM are: R=0.988, RMSE=0.207 and AAE=0.145 for the training set, and R=0.965, RMSE=0.403 and AAE=0.338 for the test set. Leave one out cross validation test was used for assessment of the predictive power and validity of models which led to cross-validation correlation coefficient QUOTE of 0.864 and 0.850 and standardized predicted relative error sum of squares (SPRESS) of 0.553 and 0.581 for LS-SVM and MLR models, respectively.

  14. Inhibitory activity of Thai condiments on pandemic strain of Vibrio parahaemolyticus.

    PubMed

    Vuddhakul, Varaporn; Bhoopong, Phuangthip; Hayeebilan, Fadeeya; Subhadhirasakul, Sanan

    2007-06-01

    Antibacterial activity of 13 condiments used in Thai cooking was investigated with a pandemic strain of Vibrio parahaemolyticus. Using a disk diffusion technique, freshly squeezed extracts from galangal, garlic and lemon, at a concentration of 10 microl/disk produced a clear zone of 13.6+/-0.5, 11.6+/-0.5 and 8.6+/-1.2mm, respectively. The inhibitory activity of these 3 condiments on pandemic strains was not significantly different from that on non-pandemic strains of V. parahaemolyticus. Because of its popularity in seafood cooking, galangal was subjected to further investigation. Only a chloroform extract of galangal inhibited growth of V. parahaemolyticus producing a clear zone of 9.5+/-0.5, 12.0+/-0 and 13.5+/-0.5mm diameter at concentrations of 25, 50 and 100 microg/disk, respectively. One active component is identified as 1'-acetoxychavicol acetate. The activity of galangal was not reduced at pH 3 or in the presence of 0.15% bile salt but was reduced by freeze and spray drying. Heating a fresh preparation of galangal to 100 degrees C but not 50 degrees C for 30 min also reduced growth inhibition. Therefore, using fresh galangal in cooking was recommended. The MIC and MBC of a freshly squeezed preparation of galangal were 1:16 and 1:16, respectively. This is the first report of an inhibitory activity of a Thai medicinal plant, galangal that is used in Thai cooking, on the pandemic strain of V. parahaemolyticus.

  15. Dibenzocyclooctadiene lignans from Schisandra chinensis and their inhibitory activity on NO production in lipopolysaccharide-activated microglia cells.

    PubMed

    Hu, Di; Yang, Zhiyou; Yao, Xuechun; Wang, Hua; Han, Na; Liu, Zhihui; Wang, Yu; Yang, Jingyu; Yin, Jun

    2014-08-01

    Four dibenzocyclooctadiene lignans, schisanchinins A-D, and 10 known compounds were isolated from the EtOAc extract of fruits of Schisandra chinensis (Turcz.) Baill. Structures of compounds 1-4 were elucidated using a combination of spectroscopic techniques, including MS, UV and IR, NMR ((1)H NMR, (13)C NMR, HMQC, HMBC). The stereochemistry of the chiral centers and the biphenyl configuration were determined using NOESY, as well as analysis of CD spectra. In vitro activity assays showed that 11 of the 14 compounds exhibited inhibitory activity on lipopolysaccharide (LPS)-induced NO release in primary murine BV2 microglia cells.

  16. Signaling pathways engaged by NK cell receptors: double concerto for activating receptors, inhibitory receptors and NK cells.

    PubMed

    Tomasello, E; Bléry, M; Vély, F; Vivier, E

    2000-04-01

    Despite the absence of antigen-specific receptors at their surface, NK cells can selectively eliminate virus-infected cells, tumor cells and allogenic cells. A dynamic and precisely coordinated balance between activating and inhibitory receptors governs NK cell activation programs. Multiple activating and inhibitory NK cell surface molecules have been described, a group of them acting as receptors for MHC class I molecules. In spite of their heterogeneity, activating NK cell receptors present remarkable structural and functional homologies with T cell- and B cell-antigen receptors. Inhibitory NK cell receptors operate at early stages of activating cascades by recruiting protein tyrosine phosphatases via intra- cytoplasmic motifs (ITIM), a strategy which is widely conserved in hematopoietic and non-hematopoietic cells.

  17. Inhibitory responses in Aplysia pleural sensory neurons act to block excitability, transmitter release, and PKC Apl II activation.

    PubMed

    Dunn, Tyler W; Farah, Carole A; Sossin, Wayne S

    2012-01-01

    Expression of the 5-HT(1Apl(a)) receptor in Aplysia pleural sensory neurons inhibited 5-HT-mediated translocation of the novel PKC Apl II in sensory neurons and prevented PKC-dependent synaptic facilitation at sensory to motoneuron synapses (Nagakura et al. 2010). We now demonstrate that the ability of inhibitory receptors to block PKC activation is a general feature of inhibitory receptors and is found after expression of the 5-HT(1Apl(b)) receptor and with activation of endogenous dopamine and FMRFamide receptors in sensory neurons. Pleural sensory neurons are heterogeneous for their inhibitory response to endogenous transmitters, with dopamine being the most prevalent, followed by FMRFamide, and only a small number of neurons with inhibitory responses to 5-HT. The inhibitory response is dominant, reduces membrane excitability and synaptic efficacy, and can reverse 5-HT facilitation at both naive and depressed synapses. Indeed, dopamine can reverse PKC translocation during the continued application of 5-HT. Reversal of translocation can also be seen after translocation mediated by an analog of diacylglycerol, suggesting inhibition is not through blockade of diacylglycerol production. The effects of inhibition on PKC translocation can be rescued by phosphatidic acid, consistent with the inhibitory response involving a reduction or block of production of this lipid. However, phosphatidic acid could not recover PKC-dependent synaptic facilitation due to an additional inhibitory effect on the non-L-type calcium flux linked to synaptic transmission. In summary, we find a novel mechanism downstream of inhibitory receptors linked to inhibition of PKC activation in Aplysia sensory neurons. PMID:21994260

  18. Cholinesterases inhibitory and antioxidant activities of Harpagophytum procumbens from in vitro systems.

    PubMed

    Georgiev, Milen I; Alipieva, Kalina; Orhan, Ilkay Erdogan

    2012-02-01

    A previous report showed that extracts of cell suspension and transformed root cultures of Harpagophytum procumbens (commonly known as Devil's claw), an African plant with high medicinal value, exhibit strong antiinflammatory characteristics. The present work tests the ability of extracts, phenylethanoid-containing fractions and the major phenylethanoid glycoside isolated from the Devil's claw cultures, to inhibit acetylcholinesterase and butyrylcholinesterase, and the antioxidant activity in iron-related systems (e.g. ferric-reducing antioxidant power and ferrous ion-chelating capacity). The results indicated that the phenylethanoid fractions may be attractive for various commercial purposes since they displayed significant cholinesterase inhibitory activity (even higher than that of pure galanthamine in the case of butyrylcholinesterase inhibition assay). Crude methanolic extracts from cell and hairy root cultures of Devil's claw exhibited strong ferrous ion-chelating capacity (1.5-2 times higher than pure butylated hydroxyanisole, used as positive standard). PMID:21721061

  19. Synthesis and characterization of tritylthioethanamine derivatives with potent KSP inhibitory activity.

    PubMed

    Rodriguez, Delany; Ramesh, Chinnasamy; Henson, Lauren H; Wilmeth, Lori; Bryant, Bj K; Kadavakollu, Samuel; Hirsch, Rebecca; Montoya, Johnelle; Howell, Porsha R; George, Jon M; Alexander, David; Johnson, Dennis L; Arterburn, Jeffrey B; Shuster, Charles B

    2011-09-15

    Assembly of a bipolar mitotic spindle requires the action of class 5 kinesins, and inhibition or depletion of this motor results in mitotic arrest and apoptosis. S-Trityl-l-cysteine is an allosteric inhibitor of vertebrate Kinesin Spindle Protein (KSP) that has generated considerable interest due to its anti-cancer properties, however, poor pharmacological properties have limited the use of this compound. We have modified the triphenylmethyl and cysteine groups, guided by biochemical and cell-based assays, to yield new cysteinol and cysteamine derivatives with increased inhibitory activity, greater efficacy in model systems, and significantly enhanced potency against the NCI60 tumor panel. These results reveal a promising new class of conformationally-flexible small molecules as allosteric KSP inhibitors for use as research tools, with activities that provide impetus for further development as anti-tumor agents.

  20. α-Glucosidase inhibitory activity of marine sponges collected in Mauritius waters.

    PubMed

    Ramanjooloo, Avin; Cresteil, Thierry; Lebrasse, Cindy; Beedessee, Girish; Oogarah, Preeti; van Soest, Rob W M; Marie, Daniel E P

    2015-01-01

    This report describes the use of α-glucosidase to evaluate the anti-diabetic potential of extracts from marine sponges collected in the Mauritius waters. Initial screening at 1.0 mg/mL of 141 extracts obtained from 47 sponge species revealed 10 extracts with inhibitory activity greater than 85%. Seven of the 10 extracts were further tested at 0.1 and 0.01 mg/mL and only the methanol extract of two sponges namely Acanthostylotella sp. (ASSM) and Echinodictyum pykei (EPM) showed inhibition activity greater than 60% at 0.1 mg/mL with an IC50 value of 0.16 ± 0.02 and 0.04 ± 0.01 mg/mL, respectively, while being inactive at 0.01 mg/mL.

  1. Labdane-type diterpenoids from Leonurus heterophyllus and their cholinesterase inhibitory activity.

    PubMed

    Hung, Tran Manh; Luan, Tran Cong; Vinh, Bui The; Cuong, To Dao; Min, Byung Sun

    2011-04-01

    In the course of screening plants used in natural medicines as memory enhancers, a 70% ethanol extract of the aerial parts of Leonurus heterophyllus showed significant AChE inhibitory activity. Bioassay-guided fractionation and repeated column chromatography led to the isolation of a new labdane-type diterpenoids (1), named leoheteronin F, and six known compounds (2-7). The chemical structures of isolated compounds were elucidated based on extensive 1D and 2D NMR spectroscopic data. The isolates 1-7 were investigated in vitro for their anticholinesterase activity using mouse cortex AChE enzyme. Leoheteronin A (5) and leopersin G (7), which possess a 15,16-epoxy group at the side chain, were found to be potent in the inhibition of AChE.

  2. Feedback Activation of Leukemia Inhibitory Factor Receptor Limits Response to Histone Deacetylase Inhibitors in Breast Cancer.

    PubMed

    Zeng, Hanlin; Qu, Jia; Jin, Nan; Xu, Jun; Lin, Chenchu; Chen, Yi; Yang, Xinying; He, Xiang; Tang, Shuai; Lan, Xiaojing; Yang, Xiaotong; Chen, Ziqi; Huang, Min; Ding, Jian; Geng, Meiyu

    2016-09-12

    Histone deacetylase (HDAC) inhibitors have demonstrated clinical benefits in subtypes of hematological malignancies. However, the efficacy of HDAC inhibitors in solid tumors remains uncertain. This study takes breast cancer as a model to understand mechanisms accounting for limited response of HDAC inhibitors in solid tumors and to seek combination solutions. We discover that feedback activation of leukemia inhibitory factor receptor (LIFR) signaling in breast cancer limits the response to HDAC inhibition. Mechanistically, HDAC inhibition increases histone acetylation at the LIFR gene promoter, which recruits bromodomain protein BRD4, upregulates LIFR expression, and activates JAK1-STAT3 signaling. Importantly, JAK1 or BRD4 inhibition sensitizes breast cancer to HDAC inhibitors, implicating combination inhibition of HDAC with JAK1 or BRD4 as potential therapies for breast cancer. PMID:27622335

  3. Some aspects of the inhibitory activity of hypolaetin-8-glucoside in acute inflammation.

    PubMed

    Villar, A; Gascó, M A; Alcaraz, M J

    1987-07-01

    Hypolaetin-8-glucoside (H-8-G) has been examined for its mode of action in several models of acute inflammation. Its anti-inflammatory activity in carrageenan-induced inflammation of the rat hind-paw is not affected either by adrenalectomy or by phentolamine given with propranolol. H-8-G and its aglycone, hypolaetin, did not antagonize the actions of histamine, 5-hydroxytryptamine (5-HT), bradykinin or prostaglandin E2 (PGE2) on various smooth muscle preparations in-vitro, but protected erythrocytes from heat-induced lysis. The glycoside was more potent than troxerutin on capillary permeability increased by histamine and exerted inhibitory effects on protein exudation, leucocyte migration and beta-glucuronidase activity in the carrageenan air pouch, thereby showing some difference from indomethacin. These results are discussed in relation to the features of non-steroidal anti-inflammatory drugs (NSAID) and flavonoid anti-inflammatory actions.

  4. Feeding deterrent and growth inhibitory activities of PONNEEM, a newly developed phytopesticidal formulation against Helicoverpa armigera (Hubner)

    PubMed Central

    Packiam, Soosaimanickam Maria; Baskar, Kathirvelu; Ignacimuthu, Savarimuthu

    2014-01-01

    Objective To assess the feeding deterrent, growth inhibitory and egg hatchability effects of PONNEEM on Helicoverpa armigera (H. armigera). Methods Five oil formulations were prepared at different ratios to assess the feeding deterrent, growth inhibitory and egg hatchability effects on H. armigera. Results Invariably all the newly formulated phytopesticidal oil formulations showed the feeding deterrent and growth inhibitory activities against H. armigera. The maximum feeding deterrent activity of 88.44% was observed at 15 µL/L concentration of PONNEEM followed by formulation A (74.54%). PONNEEM was found to be effective in growth inhibitory activities and egg hatchability at 10 µL/L concentration. It exhibited statistically significant feeding deterrent activity and growth inhibitory activity compared with all the other treatments. Conclusions PONNEEM was found to be effective phytopesticidal formulation to control the larval stage of H. armigera. This is the first report for the feeding deterrent activity of PONNEEM against H. armigera. This newly formulated phytopesticide was patented in India. PMID:25183105

  5. The NRTIs Lamivudine, Stavudine and Zidovudine Have Reduced HIV-1 Inhibitory Activity in Astrocytes

    PubMed Central

    Gray, Lachlan R.; Tachedjian, Gilda; Ellett, Anne M.; Roche, Michael J.; Cheng, Wan-Jung; Guillemin, Gilles J.; Brew, Bruce J.; Turville, Stuart G.; Wesselingh, Steve L.; Gorry, Paul R.; Churchill, Melissa J.

    2013-01-01

    HIV-1 establishes infection in astrocytes and macroage-lineage cells of the central nervous system (CNS). Certain antiretroviral drugs (ARVs) can penetrate the CNS, and are therefore often used in neurologically active combined antiretroviral therapy (Neuro-cART) regimens, but their relative activity in the different susceptible CNS cell populations is unknown. Here, we determined the HIV-1 inhibitory activity of CNS-penetrating ARVs in astrocytes and macrophage-lineage cells. Primary human fetal astrocytes (PFA) and the SVG human astrocyte cell line were used as in vitro models for astrocyte infection, and monocyte-derived macrophages (MDM) were used as an in vitro model for infection of macrophage-lineage cells. The CNS-penetrating ARVs tested were the nucleoside reverse transcriptase inhibitors (NRTIs) abacavir (ABC), lamivudine (3TC), stavudine (d4T) and zidovudine (ZDV), the non-NRTIs efavirenz (EFV), etravirine (ETR) and nevirapine (NVP), and the integrase inhibitor raltegravir (RAL). Drug inhibition assays were performed using single-round HIV-1 entry assays with luciferase viruses pseudotyped with HIV-1 YU-2 envelope or vesicular stomatitis virus G protein (VSV-G). All the ARVs tested could effectively inhibit HIV-1 infection in macrophages, with EC90s below concentrations known to be achievable in the cerebral spinal fluid (CSF). Most of the ARVs had similar potency in astrocytes, however the NRTIs 3TC, d4T and ZDV had insufficient HIV-1 inhibitory activity in astrocytes, with EC90s 12-, 187- and 110-fold greater than achievable CSF concentrations, respectively. Our data suggest that 3TC, d4T and ZDV may not adequately target astrocyte infection in vivo, which has potential implications for their inclusion in Neuro-cART regimens. PMID:23614033

  6. Associations of Physical Activity, Sports Participation and Active Commuting on Mathematic Performance and Inhibitory Control in Adolescents

    PubMed Central

    Huang, Tao; Gejl, Anne Kær; Froberg, Karsten

    2016-01-01

    Objectives To examine objectively measured physical activity level, organized sports participation and active commuting to school in relation to mathematic performance and inhibitory control in adolescents. Methods The design was cross-sectional. A convenient sample of 869 sixth and seventh grade students (12–14 years) was invited to participate in the study. A total of 568 students fulfilled the inclusion criteria and comprised the final sample for this study. Mathematic performance was assessed by a customized test and inhibitory control was assessed by a modified Eriksen flanker task. Physical activity was assessed with GT3X and GT3X+ accelerometers presented in sex-specific quartiles of mean counts per minute and mean minutes per day in moderate-to-vigorous physical activity. Active commuting and sports participation was self-reported. Mixed model regression was applied. Total physical activity level was stratified by bicycling status in order to bypass measurement error subject to the accelerometer. Results Non-cyclists in the 2nd quartile of counts per minute displayed a higher mathematic score, so did cyclists in the 2nd and 3rd quartile of moderate-to-vigorous physical activity relative to the least active quartile. Non-cyclists in the 3rd quartile of counts per minute had an improved reaction time and cyclists in the 2nd quartile of counts per minute and moderate-to-vigorous physical activity displayed an improved accuracy, whereas non-cyclists in the 2nd quartile of counts per minute showed an inferior accuracy relative to the least active quartile. Bicycling to school and organized sports participation were positively associated with mathematic performance. Conclusions Sports participation and bicycling were positively associated with mathematic performance. Results regarding objectively measured physical activity were mixed. Although, no linear nor dose-response relationship was observed there was no indication of a higher activity level impairing the

  7. Aldose Reductase Inhibitory Activity of Compounds from  Zea mays L.

    PubMed Central

    Kim, Tae Hyeon; Kim, Jin Kyu; Kang, Young-Hee; Lee, Jae-Yong; Kang, Il Jun; Lim, Soon Sung

    2013-01-01

    Aldose reductase (AR) inhibitors have a considerable therapeutic potential against diabetes complications and do not increase the risk of hypoglycemia. Through bioassay-guided fractionation of an EtOH extract of the kernel from purple corn (Zea mays L.), 7 nonanthocyanin phenolic compounds (compound 1–7) and 5 anthocyanins (compound 8–12) were isolated. These compounds were investigated by rat lens aldose reductase (RLAR) inhibitory assays. Kinetic analyses of recombinant human aldose reductase (rhAR) were performed, and intracellular galactitol levels were measured. Hirsutrin, one of 12 isolated compounds, showed the most potent RLAR inhibitory activity (IC50, 4.78 μM). In the kinetic analyses using Lineweaver-Burk plots of 1/velocity and 1/substrate concentration, hirsutrin showed competitive inhibition against rhAR. Furthermore, hirsutrin inhibited galactitol formation in rat lens and erythrocytes sample incubated with a high concentration of galactose; this finding indicates that hirsutrin may effectively prevent osmotic stress in hyperglycemia. Therefore, hirsutrin derived from Zea mays L. may be a potential therapeutic agent against diabetes complications. PMID:23586057

  8. Melanogenesis inhibitory activity of sesquiterpenes from Canarium ovatum resin in mouse B16 melanoma cells.

    PubMed

    Kikuchi, Takashi; Watanabe, Kensuke; Tochigi, Yuichi; Yamamoto, Ayako; Fukatsu, Makoto; Ezaki, Yoichiro; Tanaka, Reiko; Akihisa, Toshihiro

    2012-08-01

    Four known sesquiterpene alcohols, i.e., 1-4, ten triterpene alcohols, i.e., 5-14, and four triterpene acids, i.e., 15-18, were isolated from the MeOH extract of Canarium ovatum resin (elemi resin). Upon evaluation of the previously described compounds 1-18 on the melanogenesis in B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH), three sesquiterpene alcohols, i.e., cryptomeridiol (1), 4-epicryptomeridiol (2), and cadin-1(14)-ene-7α,11-diol (4), exhibited inhibitory effects with 27.4-34.1 and 39.0-56.9% reduction of melanin content at 50 and 100 μM, respectively, with no or very low toxicity to the cells (80.9-103.9% of cell viability at 100 μM). Western-blot analysis revealed that compounds 1 and 2 reduced the protein levels of MITF (=microphtalmia-associated transcription factor), tyrosinase, and TRP-2 (=tyrosine-related protein 2), mostly in a concentration-dependent manner, suggesting that these compounds exhibit melanogenesis inhibitory activity on α-MSH-stimulated B16 melanoma cells by, at least in part, inhibiting the expression of MITF, followed by decreasing the expression of tyrosinase and TRP-2. Three sesquiterpene alcohols, i.e., 1, 2, and 4, are, therefore, considered to be valuable as potential skin-whitening agents.

  9. Evaluation of antioxidant and xanthine oxidase inhibitory activity of different solvent extracts of leaves of Citrullus colocynthis

    PubMed Central

    Nessa, Fazilatun; Khan, Saeed A.

    2014-01-01

    Background: Citrullus colocynthis is a folk medicinal plan of United Arab Emirates. Several studies on this plant reported and focused on the biological and toxicological profile of fruits pulp. The present study focused on the antioxidant potency of leaf extract of this plant. Aim: To evaluate the antioxidant and xanthine oxidase (XO) inhibitory activities of C. colocynthis by chemical method. Materials and Methods: Four different solvent extracts (methanol-CCM, methanol: water (1:1)-CCMW, chloroform-CCC and hexane-CCH) of leaves of C. colocynthis were investigated for their free radical scavenging activity using DPPH radical as a substrate, lipid peroxidation (LPO) inhibitory activity using a model system consisting of β-carotene-linoleic acid, superoxide radical scavenging activity (enzymatically/nonenzymatically) and XO inhibitory activity. A dose response curve was plotted for determining SC50 and IC50 values for expressing the results of free radical scavenging activity and XO inhibitory activities respectively. Results: The high polyphenolic content of CCM and CCMW extract showed highest antioxidant activity irrespective the method used for this investigation. The overall results decreased in the order of: CCM > CCMW > CCC > CCH. CCH extract was inactive towards chemically generated superoxide radical and poor DPPH radical scavengers. The results of LPO inhibitory activities of leaves extract (0.1, 0.5 and 1.0 mg/mL) also decreased in the order of: CCM > CCMW > CCC > CCH. Overall 1.0 mg/mL leaves extract showed highest antioxidant potency amongst the studied concentration. Conclusion: CCMW and CCM extract of C. colocynthis exhibited promising antioxidants and XO inhibitory activities. PMID:25002802

  10. Syntheses of new 3-thiazolyl coumarin derivatives, in vitro α-glucosidase inhibitory activity, and molecular modeling studies.

    PubMed

    Salar, Uzma; Taha, Muhammad; Khan, Khalid Mohammed; Ismail, Nor Hadiani; Imran, Syahrul; Perveen, Shahnaz; Gul, Sahib; Wadood, Abdul

    2016-10-21

    3-Thiazolylcoumarin derivatives 1-14 were synthesized via one-pot two step reactions, and screened for in vitro α-glucosidase inhibitory activity. All compounds showed inhibitory activity in the range of IC50 = 0.12 ± 0.01-16.20 ± 0.23 μM as compared to standard acarbose (IC50 = 38.25 ± 0.12 μM), and also found to be nontoxic. Molecular docking study was carried out in order to establish the structure-activity relationship (SAR) which demonstrated that electron rich centers at one and electron withdrawing centers at the other end of the molecules showed strong inhibitory activity. All the synthesized compounds were characterized by spectroscopic techniques such as EI-MS, HREI-MS, (1)H NMR and (13)C NMR. CHN analysis was also performed.

  11. Screening the methanol extracts of some Iranian plants for acetylcholinesterase inhibitory activity

    PubMed Central

    Gholamhoseinian, A.; Moradi, M.N.; Sharifi-far, F.

    2009-01-01

    Acetylcholinesterase (AChE) is the main enzyme for the breakdown of acetylcholine. Nowadays, usage of the inhibitors of this enzyme is one of the most important types of treatment of mild to moderate neurodegenerative diseases such as Alzheimer’s disease. Herbal medicines can be a new source of inhibitors of this enzyme. In this study we examined around 100 different plants to evaluate their inhibitory properties for AChE enzyme. Plants were scientifically identified and their extracts were prepared by methanol percolation. Acetylcholinesterase activity was measured using a colorimetric method in the presence or absence of the extracts. Eserine was used as a positive control. Methanol extracts of the Levisticum officinale, Bergeris integrima and Rheum ribes showed more than 50% AChE inhibitory activity. The inhibition kinetics were studied in the presence of the most effective extracts. L. officinale and B. integrima inhibited AChE activity in a non-competitive manner, while R. ribes competitively inhibitied the enzyme as revealed by double-reciprocal Linweaver-Burk plot analysis. Under controlled condition, Km and Vmax values of the enzyme were found to be 9.4 mM and 0.238 mM/min, respectively. However, in the presence of L. officinale, B. integrima, and R. ribes extracts, Vmax values were 0.192, 0.074 and 0.238 mM/min, respectively. Due to the competitive inhibition of the enzyme by R. ribes extract, the Km value of 21.2 mM was obtained. The concentration required for 50% enzyme inhibition (IC50 value) was 0.5, 0.9, and 0.95 mg/ml for the L. officinale, B. integrima and R. ribes extracts, respectively. The IC50 of the eserine was determined to be 0.8 mg/ml. PMID:21589805

  12. Probing the origins of aromatase inhibitory activity of disubstituted coumarins via QSAR and molecular docking

    PubMed Central

    Worachartcheewan, Apilak; Suvannang, Naravut; Prachayasittikul, Supaluk; Prachayasittikul, Virapong; Nantasenamat, Chanin

    2014-01-01

    This study investigated the quantitative structure-activity relationship (QSAR) of imidazole derivatives of 4,7-disubstituted coumarins as inhibitors of aromatase, a potential therapeutic protein target for the treatment of breast cancer. Herein, a series of 3,7- and 4,7-disubstituted coumarin derivatives (1-34) with R1 and R2 substituents bearing aromatase inhibitory activity were modeled as a function of molecular and quantum chemical descriptors derived from low-energy conformer geometrically optimized at B3LYP/6-31G(d) level of theory. Insights on origins of aromatase inhibitory activity was afforded by the computed set of 7 descriptors comprising of F10[N-O], Inflammat-50, Psychotic-80, H-047, BELe1, B10[C-O] and MAXDP. Such significant descriptors were used for QSAR model construction and results indicated that model 4 afforded the best statistical performance. Good predictive performance were achieved as verified from the internal (comprising the training and the leave-one-out cross-validation (LOO-CV) sets) and external sets affording the following statistical parameters: R2Tr = 0.9576 and RMSETr = 0.0958 for the training set; Q2CV = 0.9239 and RMSECV = 0.1304 for the LOO-CV set as well as Q2Ext = 0.7268 and RMSEExt = 0.2927 for the external set. Significant descriptors showed correlation with functional substituents, particularly, R1 in governing high potency as aromatase inhibitor. Molecular docking calculations suggest that key residues interacting with the coumarins were predominantly lipophilic or non-polar while a few were polar and positively-charged. Findings illuminated herein serve as the impetus that can be used to rationally guide the design of new aromatase inhibitors. PMID:26417339

  13. Inhibitory effect of synthetic cannabinoids on CYP1A activity in mouse liver microsomes.

    PubMed

    Ashino, Takashi; Hakukawa, Kanae; Itoh, Yuka; Numazawa, Satoshi

    2014-01-01

    Synthetic cannabinoids developed by chemical modification are believed to bind to cannabinoid receptors and cause neurological effects similar to cannabis; however, their effects on drug metabolizing enzymes are unknown. This study aimed to elucidate the effect of synthetic cannabinoids on cytochrome P450 1A activity. Naphthoylindole, a basic structure of the major synthetic cannabinoids, strongly inhibited CYP1A activity in a competitive manner; the apparent Ki value was 0.40 μM. The N-Alkylated derivatives of naphthoylindole, MAM-2201 and JWH-019, also inhibited CYP1A activity in a concentration-dependent manner; however, their inhibitory effects were weaker than naphthoylindole. An adamantylamidoindole derivative, STS-135, showed inhibition of CYP1A activity in a concentrationdependent manner, but the adamantoylindole derivatives, AB-001 and AM-1248, did not. A tetramethylcyclopropanoylindole derivative, UR-144, showed a weak inhibition of CYP1A activity at high concentrations. These results suggest that synthetic cannabinoids and their basic molecules are capable of inhibiting CYP1A enzymatic activity.

  14. Inhibitory effect of synthetic cannabinoids on CYP1A activity in mouse liver microsomes.

    PubMed

    Ashino, Takashi; Hakukawa, Kanae; Itoh, Yuka; Numazawa, Satoshi

    2014-01-01

    Synthetic cannabinoids developed by chemical modification are believed to bind to cannabinoid receptors and cause neurological effects similar to cannabis; however, their effects on drug metabolizing enzymes are unknown. This study aimed to elucidate the effect of synthetic cannabinoids on cytochrome P450 1A activity. Naphthoylindole, a basic structure of the major synthetic cannabinoids, strongly inhibited CYP1A activity in a competitive manner; the apparent Ki value was 0.40 μM. The N-Alkylated derivatives of naphthoylindole, MAM-2201 and JWH-019, also inhibited CYP1A activity in a concentration-dependent manner; however, their inhibitory effects were weaker than naphthoylindole. An adamantylamidoindole derivative, STS-135, showed inhibition of CYP1A activity in a concentrationdependent manner, but the adamantoylindole derivatives, AB-001 and AM-1248, did not. A tetramethylcyclopropanoylindole derivative, UR-144, showed a weak inhibition of CYP1A activity at high concentrations. These results suggest that synthetic cannabinoids and their basic molecules are capable of inhibiting CYP1A enzymatic activity. PMID:25374372

  15. Phosphodiesterase-1 Inhibitory Activity of Two Flavonoids Isolated from Pistacia integerrima J. L. Stewart Galls

    PubMed Central

    Saleem, Muhammad; Uddin, Ghias; Siddiqui, Bina S.; Khan, Haroon; Raza, Muslim; Hamid, Syeda Zehra; Khan, Ajmal; Maione, Francesco; Mascolo, Nicola

    2015-01-01

    Pistacia integerrima is one of twenty species among the genus Pistacia. Long horn-shaped galls that develop on this plant are harvested and used in Ayurveda and Indian traditional medicine to make “karkatshringi”, a herbal medicine used for the treatment of asthma and different disorders of respiratory tract. However, until now, the molecular mechanisms of action of “karkatshringi” and its chemical characterization are partially known. This study deals with the isolation and characterization of the active constituents from the methanolic extract of P. integerrima galls and it was also oriented to evaluate in vitro and in silico their potential enzymatic inhibitory activity against phosphodiesterase-1 (PDE1), a well-known enzyme involved in airway smooth muscle activity and airway inflammation. Our results showed that the methanolic extract of P. integerrima galls and some of its active constituents [naringenin (1) and 3,5,7,4′-tetrahydroxy-flavanone (2)] are able in vitro to inhibit PDE1 activity (59.20 ± 4.95%, 75.90 ± 5.90%, and 65.25 ± 5.25%, resp.) and demonstrate in silico an interesting interaction with this enzymatic site. Taken together, our results add new knowledge of chemical constituents responsible for the biological activity of P. integerrima and contextually legitimate the use of this plant in folk medicine. PMID:25945110

  16. Sesquiterpenoids from the Rhizomes of Curcuma phaeocaulis and Their Inhibitory Effects on LPS-Induced TLR4 Activation.

    PubMed

    Jang, Hyun-Jae; Kim, Jin-Han; Oh, Hyun-Mee; Kim, Min-Suk; Jo, Jin Ha; Jung, Kyungsook; Lee, Soyoung; Kim, Young-Ho; Lee, Woo Song; Lee, Seung Woong; Rho, Mun-Chual

    2016-01-01

    Two new guaiane-type (2, 6) and one new furanogermacrane-type (11) sesquiterpenoids have been isolated along with twelve known compounds from an EtOAc-soluble extract of Curcuma phaeocaulis rhizomes. The structures of the isolated compounds were elucidated using a combination of NMR, MS, and circular dichroism (CD) spectra. The inhibitory effects of each compound on lipopolysaccharide (LPS)-induced Toll-like receptor 4 (TLR4) activation in THP-1-Blue cells were assessed, and compound 4 showed more potent inhibitory activity against LPS-stimulated TLR4 activation. PMID:27373668

  17. Protease and protease inhibitory activity in pregnant and postpartum involuting uterus

    SciTech Connect

    Milwidsky, A.; Beller, U.; Palti, Z.; Mayer, M.

    1982-08-15

    The presence of two distinct proteolytic activities in the rat uterus was confirmed with /sup 14/C-labeled globin used as a sensitive protein substrate and following release of label into the trichloroacetic acid-soluble supernatant fraction. Protease I is a cytoplasmic acid protease while protease II is associated with the pellet fraction, can be extracted by 0.6 M sodium chloride, and is active at pH 7.0. Protease I activity is low during pregnancy and markedly increases at term achieving maximal activity at day 3 post partum with a subsequent decline to preterm activity values. Lactation did not affect the uterine protease I activity. Protease II activity is not significantly different during pregnancy, at term, and post partum. The presence of an inhibitor of protease I was suggested by a decrease in enzyme activity with an increased cytosolic protein concentration. The inhibitor also lessened bovine trypsin activity but had no effect on protease II. Although its inhibitory potency on trypsin fluctuated during the various uterine physiologic stages, these changes appeared to be statistically insignificant. Human uterine samples were also found to contain the two protease activities with similar changes in protease I post partum. It is suggested that, both in the rat and in man, uterine involution post partum is associated with a marked increase in activity of acid cytosolic protease, while a particulate neutral protease and a soluble inhibitor of trypsin, which are also present in uterine cells, do not appear to play a significant role in the dissolution of uterine tissues after parturition.

  18. Lactobacillus isolates from weaned piglets' mucosa with inhibitory activity against common porcine pathogens.

    PubMed

    Hacin, B; Rogelj, I; Matijasić, B B

    2008-01-01

    Twelve lactobacilli isolates from mucosa of 3-5-week-old weaned pigs were found to exert good antimicrobial activity against common porcine pathogens (S. aureus, B. cereus, E. coli, C. perfringens). Two of them produced in addition to lactic acid also considerable amounts of acetic acid, and 6 of them produced hydrogen peroxide and metabolites other than organic acids. Isolates 4/26 and 2/25 (identified as L. crispatus or L. amylovorus) were inhibitory against most strains of S. aureus, B. cereus and E. coli, and especially the strain 4/26 survived well in simulated gastric and intestinal juice. Diarrhea-causing E. coli O8K88H9 Ent(+) was successfully inhibited by the growing culture as well as by the catalase-treated and neutralized supernatant of L. reuteri 12/26. Mucin degradation and multiple resistance to antibiotics were not observed.

  19. Monoamine Oxidase Inhibitory Activity of Novel Pyrazoline Analogues: Curcumin Based Design and Synthesis.

    PubMed

    Badavath, Vishnu Nayak; Baysal, İpek; Ucar, Gulberk; Sinha, Barij Nayan; Jayaprakash, Venkatesan

    2016-01-14

    A series of new 2-methoxy-4-(5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)phenolderivatives, 4-13, were synthesized and tested for their human MAO inhibitory activity. All the compounds were found to be selective and reversible toward hMAO-A except 4, a selective inhibitor of hMAO-B and 12, a nonselective inhibitor. Compound 7 was found to be a potent inhibitor of hMAO-A with Ki = 0.06 ± 0.003 μM and was having selectivity index of (SI = 1.02 × 10(-5)). It was found to be better than standard drug, Moclobemide (hMAO-A with Ki = 0.11 ± 0.01 μM) with selectivity index of SI = 0.049. Molecular docking simulation was carried out to understand the crucial interactions responsible for selectivity and potency. PMID:26819666

  20. Abietane-type diterpenoids from the roots of Caryopteris mongolica and their cholinesterase inhibitory activities.

    PubMed

    Murata, Toshihiro; Ishikawa, Yoshinobu; Saruul, Erdenebileg; Selenge, Erdenechimeg; Sasaki, Kenroh; Umehara, Kaoru; Yoshizaki, Fumihiko; Batkhuu, Javzan

    2016-10-01

    Eleven abietane-type diterpenoids and two known abietanes were isolated from the roots of Caryopteris mongolica, and their structures were characterized. The absolute configurations at C-5 and C-10 were determined from the NMR data, including from the nuclear Overhauser effect and CD spectra, and the absolute configuration of C-16 in the hydroxypropyl group was determined via a modified Mosher's method. Furthermore, the previously unknown absolute configuration of the C-15 of cyrtophyllone B was determined to be in an R-configuration using X-ray crystallography. To estimate the preventive effects of the isolates for neurodegenerative disease development, their inhibitory activities against acetylcholinesterase (AChE) from human erythrocytes and butyrylcholinesterase (BChE) from horse serum were evaluated.

  1. Sense of impending doom: inhibitory activity in waiting blood donors who subsequently experience vasovagal symptoms.

    PubMed

    Gilchrist, Philippe T; Ditto, Blaine

    2015-01-01

    This study examined autonomic and hemodynamic processes associated with the development of naturally occurring vasovagal responses. Data from a study assessing the physiological correlates of an intervention to reduce vasovagal responses in blood donors were examined (Ditto et al., 2009). Ninety-eight participants were assigned randomly to groups that either practiced applied tension or not. Dependent variables included ratings of vasovagal symptoms, heart rate, blood pressure, and other parameters derived from ambulatory impedance cardiography. Participants who subsequently experienced vasovagal symptoms had a lower ratio between low and high frequency components (LF/HF HRV) of heart rate variability (HRV) before blood donation, suggesting lower sympathetic nervous system activity. They also showed sharper decreases in total peripheral resistance and lower respiration rates. The results suggest that vasovagal reactions that begin during anticipation of a medical procedure may be characterized by an inhibitory process from the outset and do not support the belief that reactions follow a diphasic pattern.

  2. Four new sesquiterpenes from the rhizomes of Curcuma phaeocaulis and their iNOS inhibitory activities.

    PubMed

    Ma, Jiang-Hao; Wang, Ying; Liu, Yue; Gao, Su-Yu; Ding, Li-Qin; Zhao, Feng; Chen, Li-Xia; Qiu, Feng

    2015-05-01

    Three new guaiane-type sesquiterpenes named phaeocaulisins K-M (1-3), and one germacrane-type sesquiterpenoid with new ring system of 1,5- and 1,8-ether groups named phagermadiol (4), were isolated from rhizomes of Curcuma phaeocaulis. Their structures were established based on extensive spectroscopic analysis. Compound 1, the first example of norsesquiterpene with tropone backbone, and compound 3 with a novel 1,2-dioxolane sesquiterpene alcohol were isolated from the genus Curcuma. All of the isolated compounds were tested for inhibitory activity against lipopolysaccharide-induced nitric oxide (NO) production in RAW 264.7 macrophages. Compound 3 inhibited NO production with IC50 value of 6.05 ± 0.43 μM. The plausible biosynthetic pathway for compounds 3 and 4 in C. phaeocaulis was also discussed.

  3. Xanthones from the botanical dietary supplement mangosteen (Garcinia mangostana) with aromatase inhibitory activity.

    PubMed

    Balunas, Marcy J; Su, Bin; Brueggemeier, Robert W; Kinghorn, A Douglas

    2008-07-01

    Twelve xanthone constituents of the botanical dietary supplement mangosteen (the pericarp of Garcinia mangostana) were screened using a noncellular, enzyme-based microsomal aromatase inhibition assay. Of these compounds, garcinone D (3), garcinone E (5), alpha-mangostin (8), and gamma-mangostin (9) exhibited dose-dependent inhibitory activity. In a follow-up cell-based assay using SK-BR-3 breast cancer cells that express high levels of aromatase, the most potent of these four xanthones was gamma-mangostin (9). Because xanthones may be consumed in substantial amounts from commercially available mangosteen products, the consequences of frequent intake of mangosteen botanical dietary supplements require further investigation to determine their possible role in breast cancer chemoprevention.

  4. Chemical constituents of Blumea balsamifera of Indonesia and their protein tyrosine phosphatase 1B inhibitory activity.

    PubMed

    Saifudin, Azis; Tanaka, Ken; Kadota, Shigetoshi; Tezuka, Yasuhiro

    2012-07-01

    A methanol extract of the leaves of Blumea balsamifera (L.) DC. (Asteraceae) afforded a new guaian-type sesquiterpene, epiblumeaene K (1), together with four known guaian-type sesquiterpenes (2-5), three known sesquiterpenes (6-8), and nine known flavonoids (9-17) by a combination of chromatography and preparative TLC techniques. Their structures were elucidated by extensive spectroscopic methods and comparison with the literature data. Among the isolated compounds, a known sesquiterpene, beta-caryophyllene 8R,9R-oxide (6), exhibited a significant PTP1B inhibitory activity in a dose-dependent manner, with an IC50 value of 25.8 microM (5.62 microg/mL). PMID:22908553

  5. Glucose level determines excitatory or inhibitory effects of adiponectin on arcuate POMC neuron activity and feeding.

    PubMed

    Suyama, Shigetomo; Maekawa, Fumihiko; Maejima, Yuko; Kubota, Naoto; Kadowaki, Takashi; Yada, Toshihiko

    2016-01-01

    Adiponectin regulates glucose and lipid metabolism, acting against metabolic syndrome and atherosclerosis. Accumulating evidence suggest that adiponectin acts on the brain including hypothalamic arcuate nucleus (ARC), where proopiomelanocortin (POMC) neurons play key roles in feeding regulation. Several studies have examined intracerebroventricular (ICV) injection of adiponectin and reported opposite effects, increase or decrease of food intake. These reports used different nutritional states. The present study aimed to clarify whether adiponectin exerts distinct effects on food intake and ARC POMC neurons depending on the glucose concentration. Adiponectin was ICV injected with or without glucose for feeding experiments and administered to ARC slices with high or low glucose for patch clamp experiments. We found that adiponectin at high glucose inhibited POMC neurons and increased food intake while at low glucose it exerted opposite effects. The results demonstrate that glucose level determines excitatory or inhibitory effects of adiponectin on arcuate POMC neuron activity and feeding. PMID:27503800

  6. Abietane-type diterpenoids from the roots of Caryopteris mongolica and their cholinesterase inhibitory activities.

    PubMed

    Murata, Toshihiro; Ishikawa, Yoshinobu; Saruul, Erdenebileg; Selenge, Erdenechimeg; Sasaki, Kenroh; Umehara, Kaoru; Yoshizaki, Fumihiko; Batkhuu, Javzan

    2016-10-01

    Eleven abietane-type diterpenoids and two known abietanes were isolated from the roots of Caryopteris mongolica, and their structures were characterized. The absolute configurations at C-5 and C-10 were determined from the NMR data, including from the nuclear Overhauser effect and CD spectra, and the absolute configuration of C-16 in the hydroxypropyl group was determined via a modified Mosher's method. Furthermore, the previously unknown absolute configuration of the C-15 of cyrtophyllone B was determined to be in an R-configuration using X-ray crystallography. To estimate the preventive effects of the isolates for neurodegenerative disease development, their inhibitory activities against acetylcholinesterase (AChE) from human erythrocytes and butyrylcholinesterase (BChE) from horse serum were evaluated. PMID:27298275

  7. Inhibitory activity of Aloe vera gel on some clinically isolated cariogenic and periodontopathic bacteria.

    PubMed

    Fani, Mohammadmehdi; Kohanteb, Jamshid

    2012-03-01

    Aloe vera is a medicinal plant with anti-inflammatory, antimicrobial, antidiabetic and immune-boosting properties. In the present study we investigated the inhibitory activities of Aloe vera gel on some cariogenic (Streptococcus mutans), periodontopathic (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis) and an opportunistic periodontopathogen (Bacteroides fragilis) isolated from patients with dental caries and periodontal diseases. Twenty isolates of each of these bacteria were investigated for their sensitivity to Aloe vera gel using the disk diffusion and microdilution methods. S. mutans was the species most sensitive to Aloe vera gel with a MIC of 12.5 µg/ml, while A. actinomycetemcomitans, P. gingivalis, and B. fragilis were less sensitive, with a MIC of 25-50 µg/ml (P < 0.01). Based on our present findings it is concluded that Aloe vera gel at optimum concentration could be used as an antiseptic for prevention of dental caries and periodontal diseases.

  8. Glucose level determines excitatory or inhibitory effects of adiponectin on arcuate POMC neuron activity and feeding

    PubMed Central

    Suyama, Shigetomo; Maekawa, Fumihiko; Maejima, Yuko; Kubota, Naoto; Kadowaki, Takashi; Yada, Toshihiko

    2016-01-01

    Adiponectin regulates glucose and lipid metabolism, acting against metabolic syndrome and atherosclerosis. Accumulating evidence suggest that adiponectin acts on the brain including hypothalamic arcuate nucleus (ARC), where proopiomelanocortin (POMC) neurons play key roles in feeding regulation. Several studies have examined intracerebroventricular (ICV) injection of adiponectin and reported opposite effects, increase or decrease of food intake. These reports used different nutritional states. The present study aimed to clarify whether adiponectin exerts distinct effects on food intake and ARC POMC neurons depending on the glucose concentration. Adiponectin was ICV injected with or without glucose for feeding experiments and administered to ARC slices with high or low glucose for patch clamp experiments. We found that adiponectin at high glucose inhibited POMC neurons and increased food intake while at low glucose it exerted opposite effects. The results demonstrate that glucose level determines excitatory or inhibitory effects of adiponectin on arcuate POMC neuron activity and feeding. PMID:27503800

  9. Screening of some medicinal plants from cameroon for beta-lactamase inhibitory activity.

    PubMed

    Gangoué-Piéboji, Joseph; Baurin, Stéphane; Frère, Jean-Marie; Ngassam, Pierre; Ngameni, Bathelemy; Azebaze, Anatole; Pegnyemb, Dieudonné Emmanuel; Watchueng, Jean; Goffin, Colette; Galleni, Moreno

    2007-03-01

    In efforts to find new bioactive beta-lactamase inhibitors, this study investigated 16 Cameroonian plants belonging to 10 families which were evaluated for anti-beta-lactamase activity. The investigation showed that extracts 2, 6, 3 and 5 of the 16 plants investigated presented interesting in vitro beta-lactamase inhibition (over 90%), respectively, of the beta-lactamases TEM-1, OXA-10, IMP-1 and P99. These extracts were from Mammea africana (all beta-lactamases), Garcinia lucida, G. kola (OXA-10, IMP-1 and P99), Bridelia micrantha (OXA-10, P99), Ochna afzelii (OXA-10, P99), Prunus africana (IMP-1) and Adenia lobata (TEM-1). After elimination of tannins (according to the European Pharmacopoeia) the extracts from B. micrantha, G. lucida and M. africana were tested further for their anti-beta-lactamase activity. The extracts from B. micrantha and G. lucida exhibited potent inhibitory activity, respectively, of beta-lactamase OXA-10 (IC(50) = 0.02 mg/mL) and P99 (IC(50) = 0.01 mg/mL). The anti-beta-lactamase activity of M. africana extract was weak. The isolation and the structural elucidation of the active constituents of G. lucida and B. micrantha will provide useful leads in the development of beta-lactamase inhibitors.

  10. Structural and Kinetic Analyses of Macrophage Migration Inhibitory Factor Active Site Interactions

    SciTech Connect

    Crichlow, G.; Lubetsky, J; Leng, L; Bucala, R; Lolis, E

    2009-01-01

    Macrophage migration inhibitory factor (MIF) is a secreted protein expressed in numerous cell types that counters the antiinflammatory effects of glucocorticoids and has been implicated in sepsis, cancer, and certain autoimmune diseases. Interestingly, the structure of MIF contains a catalytic site resembling the tautomerase/isomerase sites of microbial enzymes. While bona fide physiological substrates remain unknown, model substrates have been identified. Selected compounds that bind in the tautomerase active site also inhibit biological functions of MIF. It had previously been shown that the acetaminophen metabolite, N-acetyl-p-benzoquinone imine (NAPQI), covalently binds to the active site of MIF. In this study, kinetic data indicate that NAPQI inhibits MIF both covalently and noncovalently. The structure of MIF cocrystallized with NAPQI reveals that the NAPQI has undergone a chemical alteration forming an acetaminophen dimer (bi-APAP) and binds noncovalently to MIF at the mouth of the active site. We also find that the commonly used protease inhibitor, phenylmethylsulfonyl fluoride (PMSF), forms a covalent complex with MIF and inhibits the tautomerase activity. Crystallographic analysis reveals the formation of a stable, novel covalent bond for PMSF between the catalytic nitrogen of the N-terminal proline and the sulfur of PMSF with complete, well-defined electron density in all three active sites of the MIF homotrimer. Conclusions are drawn from the structures of these two MIF-inhibitor complexes regarding the design of novel compounds that may provide more potent reversible and irreversible inhibition of MIF.

  11. Determination of a-glucosidase inhibitory activity from selected Fabaceae plants.

    PubMed

    Dej-Adisai, Sukanya; Pitakbut, Thanet

    2015-09-01

    Nineteen plants from Fabaceae family, which were used in Thai traditional medicine for treatment of diabetes, were determined of α-glucosidase inhibitory activity via enzymatic reaction. In this reaction, α-glucosidase was used as enzyme, which, reacted with the substrate, p-nitrophenol-D-glucopyranoside (pNPG). After that the product, p-nitro phenol (pNP) will be occurred and observed the yellow colour at 405 nm. In this study, acarbose was used as positive standard which, inhibited this enzyme with IC₅₀ as 331 ± 4.73 μg/ml. Caesalpinia pulcherrima leaves showed the highest activity with IC₅₀ as 436.97 ± 9.44 μg/ml. Furthermore, Bauhinia malabarica leaves presented moderately activity with IC₅₀ as 745.08 ± 11.15 μg/ml. However, the other plants showed mild to none activity of α-glucosidase inhibition. Accordingly, this study can support anti-diabetes of these plants in traditional medicine and it will be the database of the biological activity of Fabaceae plant.

  12. Cytotoxic and HIV-1 enzyme inhibitory activities of Red Sea marine organisms

    PubMed Central

    2014-01-01

    Background Cancer and HIV/AIDS are two of the greatest public health and humanitarian challenges facing the world today. Infection with HIV not only weakens the immune system leading to AIDS and increasing the risk of opportunistic infections, but also increases the risk of several types of cancer. The enormous biodiversity of marine habitats is mirrored by the molecular diversity of secondary metabolites found in marine animals, plants and microbes which is why this work was designed to assess the anti-HIV and cytotoxic activities of some marine organisms of the Red Sea. Methods The lipophilic fractions of methanolic extracts of thirteen marine organisms collected from the Red Sea (Egypt) were screened for cytotoxicity against two human cancer cell lines; leukaemia (U937) and cervical cancer (HeLa) cells. African green monkey kidney cells (Vero) were used as normal non-malignant control cells. The extracts were also tested for their inhibitory activity against HIV-1 enzymes, reverse transcriptase (RT) and protease (PR). Results Cytotoxicity results showed strong activity of the Cnidarian Litophyton arboreum against U-937 (IC50; 6.5 μg/ml ±2.3) with a selectivity index (SI) of 6.45, while the Cnidarian Sarcophyton trochliophorum showed strong activity against HeLa cells (IC50; 5.2 μg/ml ±1.2) with an SI of 2.09. Other species showed moderate to weak cytotoxicity against both cell lines. Two extracts showed potent inhibitory activity against HIV-1 protease; these were the Cnidarian jelly fish Cassiopia andromeda (IC50; 0.84 μg/ml ±0.05) and the red algae Galaxura filamentosa (2.6 μg/ml ±1.29). It is interesting to note that the most active extracts against HIV-1 PR, C. andromeda and G. filamentosa showed no cytotoxicity in the three cell lines at the highest concentration tested (100 μg/ml). Conclusion The strong cytotoxicity of the soft corals L. arboreum and S. trochliophorum as well as the anti-PR activity of the jelly fish C. andromeda and the red

  13. Shifting FcγRIIA-ITAM from activation to inhibitory configuration ameliorates arthritis

    PubMed Central

    Ben Mkaddem, Sanae; Hayem, Gilles; Jönsson, Friederike; Rossato, Elisabetta; Boedec, Erwan; Boussetta, Tarek; El Benna, Jamel; Launay, Pierre; Goujon, Jean-Michel; Benhamou, Marc; Bruhns, Pierre; Monteiro, Renato C.

    2014-01-01

    Rheumatoid arthritis–associated (RA-associated) inflammation is mediated through the interaction between RA IgG immune complexes and IgG Fc receptors on immune cells. Polymorphisms within the gene encoding the human IgG Fc receptor IIA (hFcγRIIA) are associated with an increased risk of developing RA. Within the hFcγRIIA intracytoplasmic domain, there are 2 conserved tyrosine residues arranged in a noncanonical immunoreceptor tyrosine–based activation motif (ITAM). Here, we reveal that inhibitory engagement of the hFcγRIIA ITAM either with anti-hFcγRII F(ab′)2 fragments or intravenous hIgG (IVIg) ameliorates RA-associated inflammation, and this effect was characteristic of previously described inhibitory ITAM (ITAMi) signaling for hFcαRI and hFcγRIIIA, but only involves a single tyrosine. In hFcγRIIA-expressing mice, arthritis induction was inhibited following hFcγRIIA engagement. Moreover, hFcγRIIA ITAMi-signaling reduced ROS and inflammatory cytokine production through inhibition of guanine nucleotide exchange factor VAV-1 and IL-1 receptor–associated kinase 1 (IRAK-1), respectively. ITAMi signaling was mediated by tyrosine 304 (Y304) within the hFcγRIIA ITAM, which was required for recruitment of tyrosine kinase SYK and tyrosine phosphatase SHP-1. Anti-hFcγRII F(ab′)2 treatment of inflammatory synovial cells from RA patients inhibited ROS production through induction of ITAMi signaling. These data suggest that shifting constitutive hFcγRIIA-mediated activation to ITAMi signaling could ameliorate RA-associated inflammation. PMID:25061875

  14. N-containing sugars from Morus alba and their glycosidase inhibitory activities.

    PubMed

    Asano, N; Oseki, K; Tomioka, E; Kizu, H; Matsui, K

    1994-06-17

    The reexamination of N-containing sugars from the roots of Morus alba by improved purification procedures led to the isolation of eighteen N-containing sugars, including seven that were isolated from the leaves of Morus bombycis. These N-containing sugars are 1-deoxynojirimycin (1), N-methyl-1-deoxynojirimycin (2), fagomine (3), 3-epi-fagomine (4), 1,4-dideoxy-1,4-imino-D-arabinitol (5), 1,4-dideoxy-1,4-imino-D-ribitol (6), calystegin B2 (1 alpha,2 beta,3 alpha,4 beta-tetrahydroxy-nor-tropane, 7), calystegin C1 (1 alpha,2 beta,3 alpha,4 beta,6 alpha-pentahydroxy-nor-tropane, 8), 1,4-dideoxy-1,4-imino-(2-O-beta-D-glucopyranosyl)-D-arabinitol (9), and nine glycosides of 1. These glycosides consist of 2-O- and 6-O-alpha-D-galactopyranosyl-1-deoxynojirimycins (10 and 11, respectively), 2-O-, 3-O- and 4-O-alpha-D-glucopyranosyl-1-deoxynojirimycins (12, 13, and 14, respectively), and 2-O-, 3-O-, 4-O- and 6-O-beta-D-glucopyranosyl-1-deoxynojirimycins (15, 16, 17, and 18, respectively). Compound 4 is a new member of polyhydroxylated piperidine alkaloids, and the isolation of 6 is the first report of its natural occurrence. It has recently been found that the polyhydroxy-nor-tropane alkaloids possess potent glycosidase inhibitory activities. Calystegin A3 is the trihydroxy-nor-tropane, and calystegins B1 and B2 are the tetrahydroxy-nor-tropane. Calystegin C1, a new member of calystegins, is the first naturally occurring pentahydroxy-nor-tropane alkaloid. The inhibitory activities of these compounds were investigated against rat digestive glycosidases and various commercially available glycosidases.

  15. Inhibitory activity of coumarins from Artemisia capillaris against advanced glycation endproduct formation.

    PubMed

    Jung, Hyun Ah; Park, Jin Ju; Islam, Md Nurul; Jin, Seung Eun; Min, Byung-Sun; Lee, Je-Hyun; Sohn, Hee Sook; Choi, Jae Sue

    2012-06-01

    Since glycation can lead to the onset of diabetic complications due to chronic hyperglycemia, several indigenous Artemisia species were evaluated as potential inhibitors of advanced glycation endproducts (AGE). Among them, the Artemisia capillaris plant demonstrated the highest AGE inhibitory activity. Repeated column chromatography was performed to isolate a new acylated flavonoid glycoside, acacetin-7-O-(6″-O-acetyl)-β-D-glucopyranosyl-(1→2)[α-L-rhamnopyranosyl]-(1→6)-β-D-glucopyranoside, along with 11 known flavonoids (acacetin-7-O-β-D-glucopyranosyl-(1→2)[α-L-rhamnopyranosyl]-(1→6)-β-D-glucopyranoside, linarin, quercetin, hyperoside, isorhamnetin, isorhamnetin 3-galactoside, isorhamnetin 3-glucoside, isorhamnetin 3-arabinoside, isorhamnetin 3-robinobioside, arcapillin, and cirsilineol), six coumarins (umbelliferone, esculetin, scopoletin, scopolin, isoscopolin, and scoparone), and two phenolic derivatives (4,5-di-O-caffeoylquinic acid and chlorogenic acid). In determining the structure-activity relationship (SAR), it was found that the presence and position of hydroxyl group of test coumarins (coumarin, esculin, isoscopoletin, daphnetin, 4-methylcoumarin, and six isolated coumarins) may play a crucial role in AGE inhibition. A free hydroxyl group at C-7 and a glucosyl group instead of a methoxyl group at C-6 are two important parameters for the inhibitory potential of coumarins on AGE formation. A. capillaris and five key AGE inhibitors, including 4,5-di-Ocaffeoylquinic acid, umbelliferone, esculetin, esculin, and scopoletin, were identified as potential candidates for use as therapeutic or preventive agents for diabetic complications and oxidative stress-related diseases. We understand this to be the first detailed study on the SAR of coumarins in AGE inhibition.

  16. Characterization of Inhibitory GABA-A Receptor Activation during Spreading Depolarization in Brain Slice

    PubMed Central

    Aiba, Isamu; Shuttleworth, C. William

    2014-01-01

    Spreading depolarization (SD) is a slowly propagating wave of near complete depolarizations of neurons and glia. Previous studies have reported large GABA releases during SD, but there is limited understanding of how GABA release and receptor activation are regulated and influence the propagating SD wavefront, as well as an excitatory phase immediately following the passage of SD. The present study characterized GABA-A type receptor (GABAAR) currents during SD generated by KCl microinjection in acute hippocampal slices from adult mice. Spontaneous GABAAR-mediated currents (sIPSCs) were initially enhanced, and were followed by a large outward current at the wavefront. sIPSC were then transiently supressed during the late SD phase, resulting in a significant reduction of the sIPSC/sEPSC ratio. The large outward current generated during SD was eliminated by the GABAAR antagonist gabazine, but the channel potentiator/agonist propofol failed to potentiate the current, likely because of a ceiling effect. Extracellular Cl− decreases recorded during SD were reduced by the antagonist but were not increased by the potentiator. Together with effects of GABAAR modulators on SD propagation rate, these results demonstrate a significant inhibitory role of the initial GABAAR activation and suggest that intracellular Cl− loading is insufficient to generate excitatory GABAAR responses during SD propagation. These results provide a mechanistic explanation for facilitating effects of GABAAR antagonists, and the lack of inhibitory effect of GABAAR potentiators on SD propagation. In addition, selective suppression of GABA transmission in the late SD period and the lack of effect of GABAA modulators on the duration of SD suggests that GABA modulation may not be effective approach to protect neurons during the vulnerable phase of SD. PMID:25338191

  17. Cell Assembly Dynamics of Sparsely-Connected Inhibitory Networks: A Simple Model for the Collective Activity of Striatal Projection Neurons

    PubMed Central

    Angulo-Garcia, David; Berke, Joshua D.; Torcini, Alessandro

    2016-01-01

    Striatal projection neurons form a sparsely-connected inhibitory network, and this arrangement may be essential for the appropriate temporal organization of behavior. Here we show that a simplified, sparse inhibitory network of Leaky-Integrate-and-Fire neurons can reproduce some key features of striatal population activity, as observed in brain slices. In particular we develop a new metric to determine the conditions under which sparse inhibitory networks form anti-correlated cell assemblies with time-varying activity of individual cells. We find that under these conditions the network displays an input-specific sequence of cell assembly switching, that effectively discriminates similar inputs. Our results support the proposal that GABAergic connections between striatal projection neurons allow stimulus-selective, temporally-extended sequential activation of cell assemblies. Furthermore, we help to show how altered intrastriatal GABAergic signaling may produce aberrant network-level information processing in disorders such as Parkinson’s and Huntington’s diseases. PMID:26915024

  18. Synthesis, crystal structures, fluorescence and xanthine oxidase inhibitory activity of pyrazole-based 1,3,4-oxadiazole derivatives

    NASA Astrophysics Data System (ADS)

    Qi, De-Qiang; Yu, Chuan-Ming; You, Jin-Zong; Yang, Guang-Hui; Wang, Xue-Jie; Zhang, Yi-Ping

    2015-11-01

    A series of pyrazole-based 1,3,4-oxadiazole derivatives were rationally designed and synthesized in good yields by following a convenient route. All the newly synthesized molecules were fully characterized by IR, 1H NMR and elemental analysis. Eight compounds were structurally determined by single crystal X-ray diffraction analysis. The fluorescence properties of all the compounds were investigated in dimethyl sulfoxide media. In addition, these newly synthesized compounds were evaluated for in vitro inhibitory activity against commercial enzyme xanthine oxidase (XO) by measuring the formation of uric acid from xanthine. Among the compounds synthesized and tested, 3d and 3e were found to be moderate inhibitory activity against commercial XO with IC50 = 72.4 μM and 75.6 μM. The studies gave a new insight in further optimization of pyrazole-based 1,3,4-oxadiazole derivatives with excellent fluorescence properties and XO inhibitory activity.

  19. Characterization of inhibitory mechanism and antifungal activity between group-1 and group-2 phytocystatins from taro (Colocasia esculenta).

    PubMed

    Wang, Ke-Ming; Kumar, Senthil; Cheng, Yi-Sheng; Venkatagiri, Shripathi; Yang, Ai-Hwa; Yeh, Kai-Wun

    2008-10-01

    Tarocystatin from Colocasia esculenta, a group-2 phytocystatin, is a defense protein against phytopathogenic nematodes and fungi. It is composed of a highly conserved N-terminal region, which is homological to group-1 cystatin, and a repetitive peptide at the C-terminus. The purified recombinant proteins of tarocystatin, such as full-length (FL), N-terminus (Nt) and C-terminus (Ct) peptides, were produced and their inhibitory activities against papain as well as their antifungal effects were investigated. Kinetic analysis revealed that FL peptide exhibited mixed type inhibition (K(ia) = 0.098 microM and K(ib) = 0.252 microM) and Nt peptide showed competitive inhibition (K(i) = 0.057 microM), whereas Ct peptide possessed weak papain activation properties. A shift in the inhibitory pattern from competitive inhibition of Nt peptide alone to mixed type inhibition of FL peptide implied that the Ct peptide has an regulatory effect on the function of FL peptide. Based on the inhibitory kinetics of FL (group-2) and Nt (group-1) peptides on papain activity, an inhibitory mechanism of group-2 phytocystatins and a regulatory mechanism of extended Ct peptide have each been proposed. By contrast, the antifungal activity of Nt peptide appeared to be greater than that of FL peptide, and the Ct peptide showed no effect on antifungal activity, indicating that the antifungal effect is not related to proteinase inhibitory activity. The results are valid for most phytocystatins with respect to the inhibitory mechanism against cysteine proteinase.

  20. Characterization of inhibitory mechanism and antifungal activity between group-1 and group-2 phytocystatins from taro (Colocasia esculenta).

    PubMed

    Wang, Ke-Ming; Kumar, Senthil; Cheng, Yi-Sheng; Venkatagiri, Shripathi; Yang, Ai-Hwa; Yeh, Kai-Wun

    2008-10-01

    Tarocystatin from Colocasia esculenta, a group-2 phytocystatin, is a defense protein against phytopathogenic nematodes and fungi. It is composed of a highly conserved N-terminal region, which is homological to group-1 cystatin, and a repetitive peptide at the C-terminus. The purified recombinant proteins of tarocystatin, such as full-length (FL), N-terminus (Nt) and C-terminus (Ct) peptides, were produced and their inhibitory activities against papain as well as their antifungal effects were investigated. Kinetic analysis revealed that FL peptide exhibited mixed type inhibition (K(ia) = 0.098 microM and K(ib) = 0.252 microM) and Nt peptide showed competitive inhibition (K(i) = 0.057 microM), whereas Ct peptide possessed weak papain activation properties. A shift in the inhibitory pattern from competitive inhibition of Nt peptide alone to mixed type inhibition of FL peptide implied that the Ct peptide has an regulatory effect on the function of FL peptide. Based on the inhibitory kinetics of FL (group-2) and Nt (group-1) peptides on papain activity, an inhibitory mechanism of group-2 phytocystatins and a regulatory mechanism of extended Ct peptide have each been proposed. By contrast, the antifungal activity of Nt peptide appeared to be greater than that of FL peptide, and the Ct peptide showed no effect on antifungal activity, indicating that the antifungal effect is not related to proteinase inhibitory activity. The results are valid for most phytocystatins with respect to the inhibitory mechanism against cysteine proteinase. PMID:18785929

  1. Insights into cholinesterase inhibitory and antioxidant activities of five Juniperus species.

    PubMed

    Orhan, Nilufer; Orhan, Ilkay Erdogan; Ergun, Fatma

    2011-09-01

    In vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory and antioxidant activities of the aqueous and ethanol extracts of the leaves, ripe fruits, and unripe fruits of Juniperus communis ssp. nana, Juniperus oxycedrus ssp. oxycedrus, Juniperus sabina, Juniperus foetidissima, and Juniperus excelsa were investigated in the present study. Cholinesterase inhibition of the extracts was screened using ELISA microplate reader. Antioxidant activity of the extracts was tested by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging, ferrous ion-chelating, and ferric-reducing antioxidant power (FRAP) assays. Total phenol and flavonoid contents of the extracts were determined spectrophotometrically. The extracts had low or no inhibition towards AChE, whereas the leaf aqueous extract of J. foetidissima showed the highest BChE inhibition (93.94 ± 0.01%). The leaf extracts usually exerted higher antioxidant activity. We herein describe the first study on anticholinesterase and antioxidant activity by the methods of ferrous ion-chelating, superoxide radical scavenging, and ferric-reducing antioxidant power (FRAP) assays of the mentioned Juniperus species.

  2. Inhibitory effects of stress on postprandial gastric myoelectrical activity and vagal tone in healthy subjects.

    PubMed

    Yin, J; Levanon, D; Chen, J D Z

    2004-12-01

    The aim was to investigate gastric myoelectrical activity (GMA) and vagal activity in response to stress. The study was performed in 10 healthy subjects in three sessions (control, relaxation and stress). The control session was composed of 30-min recordings before and 30-min recordings after a test meal. The protocol of two other sessions was similar except that the fasting recording was extended to 60 min and the subjects were continuously watching a horror movie (stress) or guided meditation tape (relaxation) after the 30-min baseline. GMA was recorded using electrogastrography and heart rate variability (HRV) was derived from the electrocardiogram. Meal resulted in a postprandial increase in the dominant frequency (2.91 cpm vs 3.17 cpm, P < 0.007), dominant power (30.0 dB vs 32.5 dB, P < 0.05), and percentage of normal slow waves (79.8%vs 87.4%, P = 0.09). Similar responses were found in the relaxation session. Stress inhibited all these normal postprandial response and reduced the regularity of gastric slow waves (82.0%vs 66.0%, P < 0.01). In addition, spectral analysis of the HRV demonstrated an inhibition of postprandial vagal activity and an increase of postprandial sympathetic activity with stress. Stress has an inhibitory effect on postprandial GMA and this may involve both vagal and sympathetic pathway.

  3. Green Synthesis and Urease Inhibitory Activity of Spiro-Pyrimidinethiones/Spiro-Pyrimidinones-Barbituric Acid Derivatives

    PubMed Central

    Mohammadi Ziarani, Ghodsi; Asadi, Shima; Faramarzi, Sakineh; Amanlou, Massoud

    2015-01-01

    Sulfonic acid functionalized SBA-15 (SBA-Pr-SO3H) with pore size 6 nm as an efficient heterogeneous nanoporous solid acid catalyst exhibited good catalytic activity in the Biginelli-like reaction in the synthesis of spiroheterobicyclic rings with good yield and good recyclability. Spiro-pyrimidinethiones/spiro-pyrimidinones-barbituric acid derivatives were synthesized in a simple and efficient method using the one-pot three-component reaction of a cyclic 1,3- dicarbonyl compounds (barbituric acid), an aromatic aldehyde and urea or thiourea in the presence of nanoporous silica SBA-Pr-SO3H under solvent free conditions. Urease inhibitory activity of spiro compounds were tested against Jack bean urease using Berthelot alkaline phenol–hypochlorite method. Five of 13 compounds were inhibitor and two of them were enzyme activators. Analysis of the docking results showed that, in most of the spiro molecules, one of the carbonyl groups is coordinated with both nickel atoms, while the other one is involved in the formation of hydrogen bonds with important active-site residues. The effect of inserting two methyl groups on N atoms of barbiturate ring, S substituted, ortho, meta and para substituted compounds were investigated too. PMID:26664377

  4. Angiotensin-I Converting Enzyme (ACE) Inhibitory and Anti-Oxidant Activities of Sea Cucumber (Actinopyga lecanora) Hydrolysates.

    PubMed

    Ghanbari, Raheleh; Zarei, Mohammad; Ebrahimpour, Afshin; Abdul-Hamid, Azizah; Ismail, Amin; Saari, Nazamid

    2015-01-01

    In recent years, food protein-derived hydrolysates have received considerable attention because of their numerous health benefits. Amongst the hydrolysates, those with anti-hypertensive and anti-oxidative activities are receiving special attention as both activities can play significant roles in preventing cardiovascular diseases. The present study investigated the angiotensin-I converting enzyme (ACE) inhibitory and anti-oxidative activities of Actinopyga lecanora (A. lecanora) hydrolysates, which had been prepared by alcalase, papain, bromelain, flavourzyme, pepsin, and trypsin under their optimum conditions. The alcalase hydrolysate showed the highest ACE inhibitory activity (69.8%) after 8 h of hydrolysis while the highest anti-oxidative activities measured by 2,2-diphenyl 1-1-picrylhydrazyl radical scavenging (DPPH) (56.00%) and ferrous ion-chelating (FIC) (59.00%) methods were exhibited after 24 h and 8 h of hydrolysis, respectively. The ACE-inhibitory and anti-oxidative activities displayed dose-dependent trends, and increased with increasing protein hydrolysate concentrations. Moreover, strong positive correlations between angiotensin-I converting enzyme (ACE) inhibitory and anti-oxidative activities were also observed. This study indicates that A. lecanora hydrolysate can be exploited as a source of functional food owing to its anti-oxidant as well as anti-hypertension functions. PMID:26690117

  5. Angiotensin-I Converting Enzyme (ACE) Inhibitory and Anti-Oxidant Activities of Sea Cucumber (Actinopyga lecanora) Hydrolysates

    PubMed Central

    Ghanbari, Raheleh; Zarei, Mohammad; Ebrahimpour, Afshin; Abdul-Hamid, Azizah; Ismail, Amin; Saari, Nazamid

    2015-01-01

    In recent years, food protein-derived hydrolysates have received considerable attention because of their numerous health benefits. Amongst the hydrolysates, those with anti-hypertensive and anti-oxidative activities are receiving special attention as both activities can play significant roles in preventing cardiovascular diseases. The present study investigated the angiotensin-I converting enzyme (ACE) inhibitory and anti-oxidative activities of Actinopyga lecanora (A. lecanora) hydrolysates, which had been prepared by alcalase, papain, bromelain, flavourzyme, pepsin, and trypsin under their optimum conditions. The alcalase hydrolysate showed the highest ACE inhibitory activity (69.8%) after 8 h of hydrolysis while the highest anti-oxidative activities measured by 2,2-diphenyl 1-1-picrylhydrazyl radical scavenging (DPPH) (56.00%) and ferrous ion-chelating (FIC) (59.00%) methods were exhibited after 24 h and 8 h of hydrolysis, respectively. The ACE-inhibitory and anti-oxidative activities displayed dose-dependent trends, and increased with increasing protein hydrolysate concentrations. Moreover, strong positive correlations between angiotensin-I converting enzyme (ACE) inhibitory and anti-oxidative activities were also observed. This study indicates that A. lecanora hydrolysate can be exploited as a source of functional food owing to its anti-oxidant as well as anti-hypertension functions. PMID:26690117

  6. Simultaneous quantitative analysis of 12 methoxyflavones with melanogenesis inhibitory activity from the rhizomes of Kaempferia parviflora.

    PubMed

    Ninomiya, Kiyofumi; Matsumoto, Taku; Chaipech, Saowanee; Miyake, Sohachiro; Katsuyama, Yushi; Tsuboyama, Akihiro; Pongpiriyadacha, Yutana; Hayakawa, Takao; Muraoka, Osamu; Morikawa, Toshio

    2016-04-01

    A methanol extract from the rhizomes of Kaempferia parviflora Wall. ex Baker (Zingiberaceae) has shown inhibitory effects against melanogenesis in theophylline-stimulated murine B16 melanoma 4A5 cells (IC50 = 9.6 μg/mL). Among 25 flavonoids and three acetophenones isolated previously (1-28), several constituents including 5-hydroxy-7,3',4'-trimethoxyflavone (6, IC50 = 8.8 μM), 5,7,3',4'-tetramethoxyflavone (7, 8.6 μM), 5,3'-dihydroxy-3,7,4'-trimethoxyflavone (12, 2.9 μM), and 5-hydroxy-3,7,3',4'-tetramethoxyflavone (13, 3.5 μM) showed inhibitory effects without notable cytotoxicity at the effective concentrations. Compounds 6, 7, 12, and 13 inhibited the expression of tyrosinase, tyrosine-related protein (TRP)-1, and TRP-2 mRNA, which could be the mechanism of their melanogenesis inhibitory activity. In addition, a quantitative analytical method for 12 methoxyflavones (1, 2, 4-11, 13, and 14) in the extract was developed using HPLC. The optimal condition for separation and detection of these constituents were achieved on an ODS column (3 μm particle size, 2.1 mm i.d. × 100 mm) with MeOH-0.1 % aqueous acetic acid solvent systems as the mobile phase, and the detection and quantitation limits of the method were estimated to be 0.08-0.66 ng and 0.22-2.00ng, respectively. The relative standard deviation values of intra- and interday precision were lower than 0.95 and 1.08 %, respectively, overall mean recoveries of all flavonoids were 97.9-102.9 %, and the correlation coefficients of all the calibration curves showed good linearity within the test ranges. For validation of the protocol, extracts of three kinds of the plant's rhizomes collected from different regions in Thailand (Leoi, Phetchabun, and Chiang Mai provinces) were evaluated. The results indicated that the assay was reproducible, precise, and could be readily utilized for the quality evaluation of the plant materials. PMID:26711832

  7. A new iridoid glycoside and potential MRB inhibitory activity of isolated compounds from the rhizomes of Cyperus rotundus L.

    PubMed

    Zhou, Zhongliu; Yin, Wenqing; Zhang, Hualin; Feng, Zongcai; Xia, Jingmin

    2013-01-01

    A new iridoid glycoside, rotunduside (1), along with four known iridoid glycosides, 10-O-p-hydroxybenzoyltheviridoside (2), 10-O-vanilloyltheviridoside (3), 6″-O-(trans-p-coumaroyl)-procumbide (4) and loganic acid (5), was isolated from the rhizomes of Cyperus rotundus L. Their chemical structures were elucidated on the basis of UV, IR, MS and NMR spectroscopic analyses. In addition, the macrophages respiratory burst (MRB) inhibitory activity of the isolated compounds was reported. Compound 2 exhibited considerable MRB inhibitory activity in the test with IC50 value of ~37 μM. PMID:23356789

  8. Antioxidant, antibacterial and ACE-inhibitory activity of four monofloral honeys in relation to their chemical composition.

    PubMed

    León-Ruiz, Virginia; González-Porto, Amelia V; Al-Habsi, Nasser; Vera, Soledad; San Andrés, María Paz; Jauregi, Paula

    2013-11-01

    Different monofloral honeys from Castilla-La Mancha (Spain) have been studied in order to determine their main functional and biological properties. Thyme honey and chestnut honey possess the highest antioxidant capacity, which is due to their high vitamin C (in thyme honey) and total polyphenolic content (in chestnut honey). On the other hand, chestnut honey showed high antimicrobial activity against Staphylococcus aureus and Escherichia coli, whilst others had no activity against S. aureus and showed very small activity against E. coli. Moreover it was found that the antimicrobial activity measured in chestnut honey was partly due to its lysozyme content. In addition the angiotensin I-converting enzyme (ACE) inhibitory activity was measured, and the ACE inhibition is one mechanism by which antihypertensive activity is exerted in vivo. All the types of honey showed some activity but chestnut honey had the highest ACE inhibitory activity. PMID:24056722

  9. Inhibitory Potency of 4-Carbon Alkanes and Alkenes toward CYP2E1 Activity

    PubMed Central

    Hartman, Jessica H.; Miller, Grover P.; Boysen, Gunnar

    2016-01-01

    CYP2E1 has been implicated in the bioactivation of many small molecules into reactive metabolites which form adducts with proteins and DNA, and thus a better understanding of the molecular determinants of its selectivity are critical for accurate toxicological predictions. In this study, we determined the potency of inhibition of human CYP2E1 for various 4-carbon alkanes, alkenes and alcohols. In addition, known CYP2E1 substrates and inhibitors including 4-methylpyrazole, aniline, and dimethylnitrosamine were included to determine their relative potencies. Of the 1,3-butadiene-derived metabolites studied, 3,4-epoxy-1-butene was the strongest inhibitor with an IC50 of 110 μM compared to 1700 μM and 6600 μM for 1,2-butenediol and 1,2:3,4-diepoxybutane, respectively. Compared to known inhibitors, inhibitory potency of 3,4-epoxy-1-butene is between 4-methylpyrazole (IC50 = 1.8 μM) and dimethylnitrosamine (IC50 = 230 μM). All three butadiene metabolites inhibit CYP2E1 activity through a simple competitive mechanism. Among the 4-carbon compounds studied, the presence and location of polar groups seems to influence inhibitory potency. To further examine this notion, the investigation was extended to include structurally and chemically similar analogs, including propylene oxide and various butane alcohols. Those results demonstrated preferential recognition of CYP2E1 toward the type and location of polar and hydrophobic structural elements. Taken together, CYP2E1 metabolism may be modified in vivo by exposure to 4-carbon compounds, such as drugs, and nutritional constituents, a finding that highlights the complexity of exposure to mixtures. PMID:24561005

  10. Stimulation of Phenolics, Antioxidant and α-Glucosidase Inhibitory Activities During Barley (Hordeum vulgare L.) Seed Germination.

    PubMed

    Ha, K-S; Jo, S-H; Mannam, V; Kwon, Y-I; Apostolidis, E

    2016-06-01

    The rationale of this study was to enhance the nutritional quality of dry barley seeds. In this study we are evaluating the effect of germination on barley seeds relevant to total phenolic contents, antioxidant activity (in terms of DPPH free-radical scavenging) and the in vitro α-glucosidase inhibitory activities. Barley seeds were germinated for 18.5, 24, 30, 48, and 67 h and then extracted in water. The total phenolic contents, antioxidant activities and α-glucosidase inhibitory activities changed with germination time. More specifically, within the first 48 h of germination the total phenolic content increased from 1.1 mg/g fresh weight (0 h) to 3.4 mg/g fresh weight (48 h) and then slightly reduced by 67 h. Similarly, α-glucosidase inhibitory activity was significantly increased from an IC50 128.82 mg/mL (0 h) to an IC50 18.88 mg/mL (48 h) and then slightly reduced by 67 h. Significant maltase inhibitory activity was observed only with 48 h-germinated extract. Antioxidant activities increased continuously from an IC50 15.72 mg/mL at 0 h to and IC50 5.72 mg/mL after 48 h of germination. Based on our observations, barley seed germination was over after 48 h. During the progress of germination phenolic compounds are becoming available and are more easily extracted. After 48 h, lignification is initiated resulting to the decreased total phenolic content and observed antioxidant and carbohydrate hydrolyzing enzyme inhibition activities. The above results indicate the positive effect of germination in barley seeds for enhanced antioxidant and α-glucosidase inhibitory activities.

  11. Alkaloids from Hippeastrum argentinum and Their Cholinesterase-Inhibitory Activities: An in Vitro and in Silico Study.

    PubMed

    Ortiz, Javier E; Pigni, Natalia B; Andujar, Sebastián A; Roitman, German; Suvire, Fernando D; Enriz, Ricardo D; Tapia, Alejandro; Bastida, Jaume; Feresin, Gabriela E

    2016-05-27

    Two new alkaloids, 4-O-methylnangustine (1) and 7-hydroxyclivonine (2) (montanine and homolycorine types, respectively), and four known alkaloids were isolated from the bulbs of Hippeastrum argentinum, and their cholinesterase-inhibitory activities were evaluated. These compounds were identified using GC-MS, and their structures were defined by physical data analysis. Compound 2 showed weak butyrylcholinesterase (BuChE)-inhibitory activity, with a half-maximal inhibitory concentration (IC50) value of 67.3 ± 0.09 μM. To better understand the experimental results, a molecular modeling study was also performed. The combination of a docking study, molecular dynamics simulations, and quantum theory of atoms in molecules calculations provides new insight into the molecular interactions of compound 2 with BuChE, which were compared to those of galantamine.

  12. Alkaloids from Hippeastrum argentinum and Their Cholinesterase-Inhibitory Activities: An in Vitro and in Silico Study.

    PubMed

    Ortiz, Javier E; Pigni, Natalia B; Andujar, Sebastián A; Roitman, German; Suvire, Fernando D; Enriz, Ricardo D; Tapia, Alejandro; Bastida, Jaume; Feresin, Gabriela E

    2016-05-27

    Two new alkaloids, 4-O-methylnangustine (1) and 7-hydroxyclivonine (2) (montanine and homolycorine types, respectively), and four known alkaloids were isolated from the bulbs of Hippeastrum argentinum, and their cholinesterase-inhibitory activities were evaluated. These compounds were identified using GC-MS, and their structures were defined by physical data analysis. Compound 2 showed weak butyrylcholinesterase (BuChE)-inhibitory activity, with a half-maximal inhibitory concentration (IC50) value of 67.3 ± 0.09 μM. To better understand the experimental results, a molecular modeling study was also performed. The combination of a docking study, molecular dynamics simulations, and quantum theory of atoms in molecules calculations provides new insight into the molecular interactions of compound 2 with BuChE, which were compared to those of galantamine. PMID:27096334

  13. Potent inhibitory effects of N-aryl S-alkylthiocarbamate derivatives on the dopa oxidase activity of mushroom tyrosinase.

    PubMed

    Lee, Kun Ho; Koketsu, Mamoru; Choi, Sang Yoon; Lee, Kang Jin; Lee, Pyeongjae; Ishihara, Hideharu; Kim, Sun Yeou

    2005-07-01

    This study reports the potent inhibitory effect of N-aryl S-alkylthiocarbamate derivatives on mushroom tyrosinase (MT) activity. N-Aryl S-alkylthiocarbamate derivatives were found to exhibit a potent inhibitory effect on the dopa (3,4-dihydroxyphenylalanine) oxidase activity of mushroom tyrosinase. Most of the N-aryl S-alkylthiocarbamate derivatives (compounds from A to J) exhibited higher inhibitory effects than kojic acid (IC50=318 microM), a well known tyrosinase inhibitor. Tyrosinase was the most inhibited by S-phenetyl N-phenylthiocarbamate (compound E, IC50=7.25 microM), and this inhibition was 44 times stronger than that of kojic acid. Compound E exhibited 95.0% of inhibition at 100 microM. A kinetic study of MT inhibition by compound E using the Lineweaver-Burk plots analysis was performed. And the kinetics profiles observed suggest that compound E competitively inhibits MT.

  14. Antifungal and Zearalenone Inhibitory Activity of Pediococcus pentosaceus Isolated from Dairy Products on Fusarium graminearum.

    PubMed

    Sellamani, Muthulakshmi; Kalagatur, Naveen K; Siddaiah, Chandranayaka; Mudili, Venkataramana; Krishna, Kadirvelu; Natarajan, Gopalan; Rao Putcha, Venkata L

    2016-01-01

    The present study was aimed to evaluate the bio-control efficacy of Pediococcus pentosaceus isolated from traditional fermented dairy products originated from India, against the growth and zearalenone (ZEA) production of Fusarium graminearum. The cell-free supernatants of P. pentosaceus (PPCS) were prepared and chemical profiling was carried out by GC-MS and MALDI-TOF analysis. Chemical profiling of PPCS evidenced that, the presence of phenolic antioxidants, which are responsible for the antifungal activity. Another hand, MALDI-TOF analysis also indicated the presence of antimicrobial peptides. To know the antioxidant potential of PPCS, DPPH free radical scavenging assay was carried out and IC50 value was determined as 32 ± 1.89 μL/mL. The antifungal activity of P. pentosaceus was determined by dual culture overlay technique and zone of inhibition was recorded as 47 ± 2.81%, and antifungal activity of PPCS on F. graminearum was determined by micro-well dilution and scanning electron microscopic techniques. The minimum inhibitory concentration (MIC) of PPCS was determined as 66 ± 2.18 μL/mL in the present study. Also a clear variation in the micromorphology of mycelia treated with MIC value of PPCS compared to untreated control was documented. Further, the mechanism of growth inhibition was revealed by ergosterol analysis and determination of reactive oxygen species (ROS) in PPCS treated samples. The effects of PPCS on mycelial biomass and ZEA production were observed in a dose-dependent manner. The mechanism behind the suppression of ZEA production was studied by reverse transcriptase qPCR analysis of ZEA metabolic pathway genes (PKS4 and PKS13), and results showed that there is a dose dependent down-regulation of target gene expression in PPCS treated samples. The results of the present study were collectively proved that, the antifungal and ZEA inhibitory activity of PPCS against F. graminearum and it may find a potential application in agriculture and food

  15. Antifungal and Zearalenone Inhibitory Activity of Pediococcus pentosaceus Isolated from Dairy Products on Fusarium graminearum

    PubMed Central

    Sellamani, Muthulakshmi; Kalagatur, Naveen K.; Siddaiah, Chandranayaka; Mudili, Venkataramana; Krishna, Kadirvelu; Natarajan, Gopalan; Rao Putcha, Venkata L.

    2016-01-01

    The present study was aimed to evaluate the bio-control efficacy of Pediococcus pentosaceus isolated from traditional fermented dairy products originated from India, against the growth and zearalenone (ZEA) production of Fusarium graminearum. The cell-free supernatants of P. pentosaceus (PPCS) were prepared and chemical profiling was carried out by GC-MS and MALDI-TOF analysis. Chemical profiling of PPCS evidenced that, the presence of phenolic antioxidants, which are responsible for the antifungal activity. Another hand, MALDI-TOF analysis also indicated the presence of antimicrobial peptides. To know the antioxidant potential of PPCS, DPPH free radical scavenging assay was carried out and IC50 value was determined as 32 ± 1.89 μL/mL. The antifungal activity of P. pentosaceus was determined by dual culture overlay technique and zone of inhibition was recorded as 47 ± 2.81%, and antifungal activity of PPCS on F. graminearum was determined by micro-well dilution and scanning electron microscopic techniques. The minimum inhibitory concentration (MIC) of PPCS was determined as 66 ± 2.18 μL/mL in the present study. Also a clear variation in the micromorphology of mycelia treated with MIC value of PPCS compared to untreated control was documented. Further, the mechanism of growth inhibition was revealed by ergosterol analysis and determination of reactive oxygen species (ROS) in PPCS treated samples. The effects of PPCS on mycelial biomass and ZEA production were observed in a dose-dependent manner. The mechanism behind the suppression of ZEA production was studied by reverse transcriptase qPCR analysis of ZEA metabolic pathway genes (PKS4 and PKS13), and results showed that there is a dose dependent down-regulation of target gene expression in PPCS treated samples. The results of the present study were collectively proved that, the antifungal and ZEA inhibitory activity of PPCS against F. graminearum and it may find a potential application in agriculture and food

  16. PvD1 defensin, a plant antimicrobial peptide with inhibitory activity against Leishmania amazonensis.

    PubMed

    do Nascimento, Viviane V; Mello, Érica de O; Carvalho, Laís P; de Melo, Edésio J T; Carvalho, André de O; Fernandes, Katia V S; Gomes, Valdirene M

    2015-01-01

    Plant defensins are small cysteine-rich peptides and exhibit antimicrobial activity against a variety of both plant and human pathogens. Despite the broad inhibitory activity that plant defensins exhibit against different micro-organisms, little is known about their activity against protozoa. In a previous study, we isolated a plant defensin named PvD1 from Phaseolus vulgaris (cv. Pérola) seeds, which was seen to be deleterious against different yeast cells and filamentous fungi. It exerted its effects by causing an increase in the endogenous production of ROS (reactive oxygen species) and NO (nitric oxide), plasma membrane permeabilization and the inhibition of medium acidification. In the present study, we investigated whether PvD1 could act against the protozoan Leishmania amazonensis. Our results show that, besides inhibiting the proliferation of L. amazonensis promastigotes, the PvD1 defensin was able to cause cytoplasmic fragmentation, formation of multiple cytoplasmic vacuoles and membrane permeabilization in the cells of this organism. Furthermore, we show, for the first time, that PvD1 defensin was located within the L. amazonensis cells, suggesting the existence of a possible intracellular target. PMID:26285803

  17. Fluorination Effects on NOS Inhibitory Activity of Pyrazoles Related to Curcumin.

    PubMed

    Nieto, Carla I; Cabildo, María Pilar; Cornago, María Pilar; Sanz, Dionisia; Claramunt, Rosa M; Torralba, María Carmen; Torres, María Rosario; Elguero, José; García, José A; López, Ana; Acuña-Castroviejo, Darío

    2015-01-01

    A series of new (E)-3(5)-[β-(aryl)-ethenyl]-5(3)-phenyl-1H-pyrazoles bearing fluorine atoms at different positions of the aryl group have been synthesized starting from the corresponding β-diketones. All compounds have been characterized by elemental analysis, DSC as well as NMR (¹H, (13)C, (19)F and (15)N) spectroscopy in solution and in solid state. Three structures have been solved by X-ray diffraction analysis, confirming the tautomeric forms detected by solid state NMR. The in vitro study of their inhibitory potency and selectivity on the activity of nNOS and eNOS (calcium-calmodulin dependent) as well as iNOS (calcium-calmodulin independent) isoenzymes is presented. A qualitative structure-activity analysis allowed the establishment of a correlation between the presence/ absence of different substituents with the inhibition data proving that fluorine groups enhance the biological activity. (E)-3(5)-[β-(3-Fluoro-4-hydroxyphenyl)-ethenyl]-5(3)-phenyl-1H-pyrazole (13), is the best inhibitor of iNOS, being also more selective towards the other two isoforms. PMID:26343623

  18. Synthesis, structures and urease inhibitory activity of cobalt(III) complexes with Schiff bases.

    PubMed

    Jing, Changling; Wang, Cunfang; Yan, Kai; Zhao, Kedong; Sheng, Guihua; Qu, Dan; Niu, Fang; Zhu, Hailiang; You, Zhonglu

    2016-01-15

    A series of new cobalt(III) complexes were prepared. They are [CoL(1)(py)3]·NO3 (1), [CoL(2)(bipy)(N3)]·CH3OH (2), [CoL(3)(HL(3))(N3)]·NO3 (3), and [CoL(4)(MeOH)(N3)] (4), where L(1), L(2), L(3) and L(4) are the deprotonated form of N'-(2-hydroxy-5-methoxybenzylidene)-3-methylbenzohydrazide, N'-(2-hydroxybenzylidene)-3-hydroxylbenzohydrazide, 2-[(2-dimethylaminoethylimino)methyl]-4-methylphenol, and N,N'-bis(5-methylsalicylidene)-o-phenylenediamine, respectively, py is pyridine, and bipy is 2,2'-bipyridine. The complexes were characterized by infrared and UV-Vis spectra, and single crystal X-ray diffraction. The Co atoms in the complexes are in octahedral coordination. Complexes 1 and 4 show effective urease inhibitory activities, with IC50 values of 4.27 and 0.35 μmol L(-1), respectively. Complex 2 has medium activity against urease, with IC50 value of 68.7 μmol L(-1). While complex 3 has no activity against urease. Molecular docking study of the complexes with Helicobacter pylori urease was performed.

  19. Inhibitory effects on phospholipase A2 and antivenin activity of melanin extracted from Thea sinensis Linn.

    PubMed

    Hung, Yao-Ching; Sava, Vasyl; Hong, Meng-Yen; Huang, G Steven

    2004-03-01

    Antivenin activity of melanin extracted from black tea (MEBT) was reported for the first time. The antagonistic effect of MEBT was evaluated for Agkistrodon contortrix laticinctus (broadbanded copperhead), Agkistrodon halys blomhoffii (Japanese mamushi), and Crotalus atrox (western diamondback rattlesnake) snake venoms administered i.p. to ICR mice. MEBT was injected i.p. immediately after the venom administration in dose of 3 mg per mouse in the same place of venom injection. MEBT demonstrated neutralization effect against all venoms tested. The greatest antivenin effect of MEBT was found against Japanese mamushi snake venom. In this case, half the mice died within 2.5 +/- 0.7 h after injection of 0.9 mg/kg of venom. An immediate injection of MEBT substantially reduced the toxic effect of venom and extended time at the 50% level of survival up to 52.3 +/- 2.3 h. The antivenin activity of MEBT is due to chelating of Ca++ and non-specific binding of phospholipase A2. The inhibitory effect of MEBT on phospholipase A2 assessed for different venoms was similar to that obtained with pure enzyme. Low toxicity of MEBT in combination with its antagonistic activity against different venoms may allow effective life-saving treatment against snakebites. Such application of MEBT is important when identification of the snake is impossible or if specific treatment is unavailable.

  20. PvD1 defensin, a plant antimicrobial peptide with inhibitory activity against Leishmania amazonensis

    PubMed Central

    do Nascimento, Viviane V.; Mello, Érica de O.; Carvalho, Laís P.; de Melo, Edésio J.T.; Carvalho, André de O.; Fernandes, Katia V.S.; Gomes, Valdirene M.

    2015-01-01

    Plant defensins are small cysteine-rich peptides and exhibit antimicrobial activity against a variety of both plant and human pathogens. Despite the broad inhibitory activity that plant defensins exhibit against different micro-organisms, little is known about their activity against protozoa. In a previous study, we isolated a plant defensin named PvD1 from Phaseolus vulgaris (cv. Pérola) seeds, which was seen to be deleterious against different yeast cells and filamentous fungi. It exerted its effects by causing an increase in the endogenous production of ROS (reactive oxygen species) and NO (nitric oxide), plasma membrane permeabilization and the inhibition of medium acidification. In the present study, we investigated whether PvD1 could act against the protozoan Leishmania amazonensis. Our results show that, besides inhibiting the proliferation of L. amazonensis promastigotes, the PvD1 defensin was able to cause cytoplasmic fragmentation, formation of multiple cytoplasmic vacuoles and membrane permeabilization in the cells of this organism. Furthermore, we show, for the first time, that PvD1 defensin was located within the L. amazonensis cells, suggesting the existence of a possible intracellular target. PMID:26285803

  1. New urushiols with platelet aggregation inhibitory activities from resin of Toxicodendron vernicifluum.

    PubMed

    Xie, Ya; Zhang, Jie; Liu, Wenyuan; Xie, Ning; Feng, Feng; Qu, Wei

    2016-07-01

    Eight new urushiol-type compounds (1-7b), along with seven known compounds were isolated from the resin of Toxicodendron vernicifluum Stokes. Their structures were determined by extensive spectroscopic methods, included (1)H NMR, (13)C NMR, HMQC, HMBC, HRESIMS, EI-MS in combination with CD methods. All the compounds except 7a and 7b were evaluated for their anti-platelet aggregation activities in vitro. Among them, compound 5 (IC50=5.12±0.85μmol/L), with a vic-diol moiety in the long alkyl chain showed the most potent inhibitory of platelet aggregation activity induced by ADP. In addition, compound 6 showed the effect of anti-platelet aggregation induced by AA with the IC50 value of 3.09±0.70μmol/L. Thus, these compounds might be the active components to the traditional use of Resina Toxicodendri for breaking up blood stasis, which could be related to the anti-platelet aggregation. PMID:27156871

  2. Troglitazone enhances tamoxifen-induced growth inhibitory activity of MCF-7 cells

    SciTech Connect

    Yu, Hong-Nu; Noh, Eun-Mi; Lee, Young-Rae; Roh, Si-Gyun; Song, Eun-Kyung; Han, Myung-Kwan; Lee, Yong-Chul; Shim, In Kyong; Lee, Seung Jin; Jung, Sung Hoo; Kim, Jong-Suk Youn, Hyun Jo

    2008-12-05

    Peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) ligands have been identified as a potential source of therapy for human cancers. However, PPAR{gamma} ligands have a limitation for breast cancer therapy, since estrogen receptor {alpha} (ER{sub {alpha}}) negatively interferes with PPAR{gamma} signaling in breast cancer cells. Here we show that ER{sub {alpha}} inhihits PPAR{gamma} transactivity and ER{sub {alpha}}-mediated inhibition of PPAR{gamma} transactivity is blocked by tamoxifen, an estrogen receptor blocker. The activation of ER{sub {alpha}} with 17-{beta}-estradiol blocked PPRE transactivity induced by troglitazone, a PPAR{gamma} ligand, indicating the resistance of ER{sub {alpha}}-positive breast cancer cells to troglitazone. Indeed, troglitazone inhibited the growth of ER{sub {alpha}}-negative MDA-MB-231 cells more than that of ER{sub {alpha}}-positive MCF-7 cells. Combination of troglitazone with tamoxifen led to a marked increase in growth inhibition of ER{sub {alpha}}-positive MCF-7 cells compared to either agent alone. Our data indicates that troglitazone enhances the growth inhibitory activity of tamoxifen in ER{sub {alpha}}-positive MCF-7 cells.

  3. Triterpenoids of sour jujube show pronounced inhibitory effect on human tumor cells and antioxidant activity.

    PubMed

    Qiao, Aimin; Wang, Yihai; Xiang, Limin; Zhang, Zhenxue; He, Xiangjiu

    2014-10-01

    Sour jujube is a common fruit and traditional medicine in China. Bioactivity-guided fractionation of sour jujube was used to determine the chemical identity of potent antiproliferative and antioxidant constituents. Four novel ursane-type triterpenoids, together with 8 known were isolated and identified. The new triterpenoids were elucidated to be 2α,3β,13β,23-tetrahydroxy-urs-11-en-28-oic acid (3), 2α,3β-dihydroxy-urs-20(30)-en-28-oic acid (9), 2α,3β,28-trihydroxy-urs-20(30)-ene (10), and 3β,12β,13β-trihydroxy-ursan-28-oic acid (11). Among the triterpenoids isolated, 2α,3β,19α-trihydroxy-urs-12-en-28-oic acid (7), 9 and 10 showed high potent inhibitory activity toward the proliferation of HepG2 cells, which the IC50 values were lower than 5 μM. Compounds 9 and 10 also exhibited pronounced activity against MCF-7 cells, with IC50 value of 0.8 ± 0.03 and 1.5 ± 0.1 μM, respectively. Compound 10 showed high antioxidant activity with an EC50 of 0.8 ± 0.02 μM, which was 18.9 times higher than ascorbic acid in antioxidant capacity.

  4. Inhibitory action of NoxA1 on dual oxidase activity in airway cells.

    PubMed

    Pacquelet, Sandrine; Lehmann, Mandy; Luxen, Sylvia; Regazzoni, Karine; Frausto, Monika; Noack, Deborah; Knaus, Ulla G

    2008-09-01

    Imbalance between pro- and antioxidant mechanisms in the lungs can compromise pulmonary functions, including blood oxygenation, host defense, and maintenance of an anti-inflammatory environment. Thus, tight regulatory control of reactive oxygen species is critical for proper lung function. Increasing evidence supports a role for the NADPH oxidase dual oxidase (Duox) as an important source for regulated H2O2 production in the respiratory tract epithelium. In this study Duox expression, function, and regulation were investigated in a fully differentiated, mucociliary airway epithelium model. Duox-mediated H2O2 generation was dependent on calcium flux, which was required for dissociation of the NADPH oxidase regulatory protein Noxa1 from plasma membrane-bound Duox. A functional Duox1-based oxidase was reconstituted in model cell lines to permit mutational analysis of Noxa1 and Duox1. Although the activation domain of Noxa1 was not required for Duox function, mutation of a proline-rich domain in the Duox C terminus, a potential interaction motif for the Noxa1 Src homology domain 3, caused up-regulation of basal and stimulated H2O2 production. Similarly, knockdown of Noxa1 in airway cells increased basal H2O2 generation. Our data indicate a novel, inhibitory function for Noxa1 in Duox regulation. This represents a new paradigm for control of NADPH oxidase activity, where second messenger-promoted conformational change of the Nox structure promotes oxidase activation by relieving constraint induced by regulatory components.

  5. Bioactive fraction of Saraca indica prevents diabetes induced cataractogenesis: An aldose reductase inhibitory activity

    PubMed Central

    Somani, Gauresh; Sathaye, Sadhana

    2015-01-01

    Background: The present study was designed to investigate the effect of Saraca indica (SI) flowers extract and different bioactive fraction on in vitro aldose reductase (AR) inhibitory activity, high glucose-induced cataract in goat lens and in vivo streptozotocin (STZ; 45 mg/kg, i.p) induced cataract in rats. Methods: Extract of flowers of SI tested for inhibition against rat lens AR. Furthermore, bioactive fraction was investigated against high glucose-induced opacification of the lens in vitro lens culture and STZ induced diabetic cataract in rats. Identification of the bioactive component was attempted through high-performance thin-layer chromatography, high-performance liquid chromatography and liquid chromatography-mass spectrometry analysis. Results: Ethyl acetate fraction of S. indica (EASI) produced maximum inhibition that may be due to high phenolic content. Goat lenses in media containing glucose developed a distinctly opaque ring in 72 h and treatment with EASI fraction lowered lens opacity in 72 h. Prolonged treatment with EASI to STZ-induced diabetic rats inhibited the AR activity and delayed cataract progression in a dose dependent manner. Conclusion: Ethyl acetate fraction of S. indica fraction has potential to inhibit rat lens AR enzyme and prevent cataractogenesis not only in goat lens model (in vitro), but also in STZ induced diabetic rats (in vivo). This study is suggestive of the anticataract activity of EASI fraction that could be attributed to the phytoconstituents present in the same. PMID:25709218

  6. Flavonoids from Millettia nitida var. hirsutissima with their anticoagulative activities and inhibitory effects on NO production.

    PubMed

    Liao, Xiao-Lin; Luo, Jian-Guang; Kong, Ling-Yi

    2013-10-01

    Two new compounds, (2R)-7,3'-dihydroxy-6,4'-methoxyflavan (1) and (3R)-7,4'-dihydroxy-2'-methoxyisoflavan (2), along with 12 known flavonoids (3-14), were isolated from the vine stems of Millettia nitida var. hirsutissima. The structures of the isolated compounds were elucidated based on spectroscopic analyses and comparison of literature data. All of the isolates were evaluated for their effects on in-vitro anticoagulative assay and on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW264.7 macrophages. As a result, all compounds showed weak antiplatelet aggregation activities and compounds 4, 5, 7, 8 and 9 demonstrated antithrombin activity with a good dose-effect relationship from 5 to 100 μg mL⁻¹ in rabbit plasma. Compounds 8, 9, 10 and 14 exhibited inhibitory effects on LPS-induced NO production in RAW264.7 macrophages with IC₅₀ values of 4.79 ± 0.20, 8.23 ± 0.35, 5.23 ± 0.11 and 6.30 ± 0.30 μg mL⁻¹, respectively. PMID:23359229

  7. Fluorination Effects on NOS Inhibitory Activity of Pyrazoles Related to Curcumin.

    PubMed

    Nieto, Carla I; Cabildo, María Pilar; Cornago, María Pilar; Sanz, Dionisia; Claramunt, Rosa M; Torralba, María Carmen; Torres, María Rosario; Elguero, José; García, José A; López, Ana; Acuña-Castroviejo, Darío

    2015-08-28

    A series of new (E)-3(5)-[β-(aryl)-ethenyl]-5(3)-phenyl-1H-pyrazoles bearing fluorine atoms at different positions of the aryl group have been synthesized starting from the corresponding β-diketones. All compounds have been characterized by elemental analysis, DSC as well as NMR (¹H, (13)C, (19)F and (15)N) spectroscopy in solution and in solid state. Three structures have been solved by X-ray diffraction analysis, confirming the tautomeric forms detected by solid state NMR. The in vitro study of their inhibitory potency and selectivity on the activity of nNOS and eNOS (calcium-calmodulin dependent) as well as iNOS (calcium-calmodulin independent) isoenzymes is presented. A qualitative structure-activity analysis allowed the establishment of a correlation between the presence/ absence of different substituents with the inhibition data proving that fluorine groups enhance the biological activity. (E)-3(5)-[β-(3-Fluoro-4-hydroxyphenyl)-ethenyl]-5(3)-phenyl-1H-pyrazole (13), is the best inhibitor of iNOS, being also more selective towards the other two isoforms.

  8. Inhibitory activity of monoacylglycerols on biofilm formation in Aeromonas hydrophila, Streptococcus mutans, Xanthomonas oryzae, and Yersinia enterocolitica.

    PubMed

    Ham, Youngseok; Kim, Tae-Jong

    2016-01-01

    Biofilm provides a bacterial hiding place by forming a physical barrier and causing physiological changes in cells. The elimination of biofilm is the main goal of hygiene. Chemicals that are inhibitory to biofilm formation have been developed for use in food, personal hygiene products, and medical instruments. Monoacylglycerols are recognized as safe and are used in food as emulsifiers. In this study, the inhibitory activity of monoacylglycerols on bacterial biofilm formation was evaluated systematically with four bacterial strains, Aeromonas hydrophila, Streptococcus mutans, Xanthomonas oryzae, and Yersinia enterocolitica. Monoacylglycerols with two specific lengths of fatty acid moiety, monolaurin and monobehenin, were found to have strong inhibitory activity toward bacterial biofilm formation of S. mutans, X. oryzae, and Y. enterocolitica in a strain specific manner. First, this result suggested that biofilm formation was not inhibited by the detergent characteristics of monoacylglycerols. This suggestion was supported by the inhibitory action of monolaurin on biofilm development but not on the initial cell attachment of Y. enterocolitica in flow cytometric observation. Second, it was also suggested that two distinct response mechanisms to monoacylglycerols existed in bacteria. The existence of these two inhibitory response mechanisms was bacterial strain specific. PMID:27652099

  9. Phytogrowth-inhibitory activities of sulfur-containing compounds. II. The inhibitory activities of thiosalicylic acid and dihydro-2(3H)-thiophenone-related compounds on plant growth.

    PubMed

    Inamori, Y; Muro, C; Yoshioka, M; Yamada, M; Tsujibo, H; Kusano, G; Watanabe, M; Fujimoto, M

    1993-08-01

    Thiosalicylic acid (I) showed rather strong inhibitory activity on the growth of roots of all plants treated except Abelmoschus esculentus Moench at the concentration of 5.0 x 10(-4) M. This compound strongly inhibited the growth of the root of Echinochloa utilis Ohwi et Yabuno even at the low concentration of 5.0 x 10(-5) M. Dihydro-2(3H)-thiophenone (VII) also exhibited inhibitory activity on the growth of roots of all plants treated except Glycine max Merrill. Both compounds inhibited the germination of seeds of some plants at the concentration of 1.0 x 10(-3) M. In I-related compounds (I-V), methyl acetylthiosalicylate (IV) had the strongest inhibitory activity, while in VII-related compounds (VII-XI), 4-hydroxy-2(5H)-thiophenone (VIII) showed the most potent inhibitory activity. The amount of chlorophyll in the cotyledon of Brassica campestris L. subsp. rapa Hook. f. et Anders treated with all compounds except tetrahydrothiophene (XI) was lower than that of the control group.

  10. Inhibitory activity of flavonoids from Prunus davidiana and other flavonoids on total ROS and hydroxyl radical generation.

    PubMed

    Jung, Hyun Ah; Jung, Mee Jung; Kim, Ji Young; Chung, Hae Young; Choi, Jae Sue

    2003-10-01

    Since reactive oxygen species (ROS) and hydroxyl radicals (*OH) play an important role in the pathogenesis of many human degenerative diseases, much attention has focused on the development of safe and effective antioxidants. Preliminary experiments have revealed that the methanol (MeOH) extract of the stem of Prunus davidiana exerts inhibitory/scavenging activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, total ROS and peroxynitrites (ONOO-). In the present study, the antioxidant activities of this MeOH extract and the organic solvent-soluble fractions, dichloromethane (CH2Cl2), ethyl acetate (EtOAc), and n-butanol (n-BuOH), and the water layer of P. davidiana stem were evaluated for the potential to inhibit *OH and total ROS generation in kidney homogenates using 2',7'-dichlorodihydrofluorescein diacetate (DCHF-DA), and for the potential to scavenge authentic ONOO-. We also evaluated the inhibitory activity of seven flavonoids isolated from P. davidiana stem, kaempferol, kaempferol 7-O-beta-D-glucoside, (+)-catechin, dihydrokaempferol, hesperetin 5-O-beta-D-glucoside, naringenin and its 7-O-beta-D-glucoside, on the total ROS, *OH and ONOO- systems. For the further elucidation of the structure-inhibitory activity relationship of flavonoids on total ROS and *OH generation, we measured the antioxidant activity of sixteen flavonoids available, including three active flavonoids isolated from P. davidiana, on the total ROS and *OH systems. We found that the inhibitory activity on total ROS generation increases in strength with more numerous hydroxyl groups on their structures. Also, the presence of an ortho-hydroxyl group, whether on the A-ring or B-ring, and a 3-hydroxyl group on the C-ring increased the inhibitory activity on both total ROS and *OH generation.

  11. GABAA receptor activity shapes the formation of inhibitory synapses between developing medium spiny neurons

    PubMed Central

    Arama, Jessica; Abitbol, Karine; Goffin, Darren; Fuchs, Celine; Sihra, Talvinder S.; Thomson, Alex M.; Jovanovic, Jasmina N.

    2015-01-01

    Basal ganglia play an essential role in motor coordination and cognitive functions. The GABAergic medium spiny neurons (MSNs) account for ~95% of all the neurons in this brain region. Central to the normal functioning of MSNs is integration of synaptic activity arriving from the glutamatergic corticostriatal and thalamostriatal afferents, with synaptic inhibition mediated by local interneurons and MSN axon collaterals. In this study we have investigated how the specific types of GABAergic synapses between the MSNs develop over time, and how the activity of GABAA receptors (GABAARs) influences this development. Isolated embryonic (E17) MSNs form a homogenous population in vitro and display spontaneous synaptic activity and functional properties similar to their in vivo counterparts. In dual whole-cell recordings of synaptically connected pairs of MSNs, action potential (AP)-activated synaptic events were detected between 7 and 14 days in vitro (DIV), which coincided with the shift in GABAAR operation from depolarization to hyperpolarization, as detected indirectly by intracellular calcium imaging. In parallel, the predominant subtypes of inhibitory synapses, which innervate dendrites of MSNs and contain GABAAR α1 or α2 subunits, underwent distinct changes in the size of postsynaptic clusters, with α1 becoming smaller and α2 larger over time, while both the percentage and the size of mixed α1/α2-postsynaptic clusters were increased. When activity of GABAARs was under chronic blockade between 4–7 DIV, the structural properties of these synapses remained unchanged. In contrast, chronic inhibition of GABAARs between 7–14 DIV led to reduction in size of α1- and α1/α2-postsynaptic clusters and a concomitant increase in number and size of α2-postsynaptic clusters. Thus, the main subtypes of GABAergic synapses formed by MSNs are regulated by GABAAR activity, but in opposite directions, and thus appear to be driven by different molecular mechanisms. PMID

  12. Phytogrowth-inhibitory and antibacterial activities of 2,5-dihydroxy-1,4-dithiane and its derivatives.

    PubMed

    Inamori, Y; Ohno, Y; Nishihata, S; Tsujibo, H; Baba, K

    1990-01-01

    2,5-Dihydroxy-1,4-dithiane (I) and its derivatives (II-IV) showed rather marked inhibitory activities on the growth of the roots of two plant species. All compounds tested had phytogrowth-inhibitory activities. These compounds markedly inhibited the growth of the two plant species at the concentration of 1.0 x 10(-3) M. Seeds of Brassica rapa treated with 2,5-dihydroxy-2,5-dimethyl-1,4-dithiane (III) and its diacetate (IV) at the same concentration failed to germinate. Among these compounds, IV showed the most potent inhibitory activity on the two plant species. The radicles of both plant species treated with these compounds at concentrations higher than 1.0 x 10(-4) M showed negative geotropism, even though germination occurred. The compounds except for 2,5-diacetoxy-1,4-dithiane (II) also had antibacterial activities. In particular, III had rather marked antibacterial activity and its minimal inhibitory concentration (MIC) for Staphylococcus aureus IFO-3060 and Escherichia coli IFO-12734 was 4.0 micrograms/ml.

  13. Yeasts from Colombian Kumis as source of peptides with Angiotensin I converting enzyme (ACE) inhibitory activity in milk.

    PubMed

    Chaves-López, Clemencia; Tofalo, Rosanna; Serio, Annalisa; Paparella, Antonello; Sacchetti, Giampiero; Suzzi, Giovanna

    2012-09-17

    This study investigated the possibility of using yeast strains in fermented milks to obtain products with high Angiotensin I-converting enzyme (ACE) inhibitory activity and low bitter taste. Ninety-three yeast strains isolated from Colombian Kumis in different geographic regions were molecularly identified, and their milk fermentation performances were determined. Molecular identification evidenced that Galactomyces geotrichum, Pichia kudriavzevii, Clavispora lusitaniae and Candida tropicalis, were the dominant species. Eighteen out of 93 strains produced fermented milk with ACE-inhibitory (ACEI) activity values ranging from 8.69 to 88.19%. Digestion of fermented milk samples by pepsin and pancreatin demonstrated an increase in ACEI activity, with C. lusitaniae KL4A as the best producer of ACEI peptides. Moreover, sensory analysis of the products containing the major ACE-inhibitory activity pointed out that P. kudriavzevii KL84A and Kluyveromyces marxianus KL26A could be selected as potential adjunct starter cultures in Kumis, since they made a considerable contribution to the ACE inhibitory activity and produced fermented milk without bitter taste. In this study we observed that Colombian Kumis can be an excellent vehicle for the isolation of yeasts with a potential to enhance bioactive peptides produced during milk fermentation. PMID:22938834

  14. Inhibitory effect of mitragynine on human cytochrome P450 enzyme activities

    PubMed Central

    Hanapi, N. A.; Ismail, S.; Mansor, S. M.

    2013-01-01

    Context: To date, many findings reveal that most of the modern drugs have the ability to interact with herbal drugs. Aims: This study was conducted to determine the inhibitory effects of mitragynine on cytochrome P450 2C9, 2D6 and 3A4 activities. Methods and Material: The in vitro study was conducted using a high-throughput luminescence assay. Statistical Analysis: Statistical analysis was conducted using one-way ANOVA and Dunnett's test with P < 0.05 vs. control. The IC50 values were calculated using the GraphPad Prism® 5 (Version 5.01, GraphPad Software, Inc., USA). Results: Assessment using recombinant enzymes showed that mitragynine gave the strongest inhibitory effect on CYP2D6 with an IC50 value of 0.45±0.33 mM, followed by CYP2C9 and CYP3A4 with IC50 values of 9.70±4.80 and 41.32±6.74 μM respectively. Positive inhibitors appropriate for CYP2C9, CYP2D6, and CYP3A4 which are sulfaphenazole, quinidine and ketoconazole were used respectively. Vmax values of CYP2C9, CYP2D6 and CYP3A4 were 0.0005, 0.01155 and 0.0137 μM luciferin formed/pmol/min respectively. Km values of CYP2C9, CYP2D6, and CYP3A4 were 32.65, 56.01, and 103.30 μM respectively. Mitragynine noncompetitively inhibits CYP2C9 and CYP2D6 activities with the Ki values of 61.48 and 12.86 μM respectively. On the other hand, mitragynine inhibits CYP3A4 competitively with a Ki value of 379.18 μM. Conclusions: The findings of this study reveal that mitragynine might inhibit cytochrome P450 enzyme activities, specifically CYP2D6. Therefore, administration of mitragynine together with herbal or modern drugs which follow the same metabolic pathway may contribute to herb-drug interactions. PMID:24174816

  15. Central and direct regulation of testicular activity by gonadotropin-inhibitory hormone and its receptor.

    PubMed

    Ubuka, Takayoshi; Son, You Lee; Tobari, Yasuko; Narihiro, Misato; Bentley, George E; Kriegsfeld, Lance J; Tsutsui, Kazuyoshi

    2014-01-01

    Gonadotropin-inhibitory hormone (GnIH) was first identified in Japanese quail to be an inhibitor of gonadotropin synthesis and release. GnIH peptides have since been identified in all vertebrates, and all share an LPXRFamide (X = L or Q) motif at their C-termini. The receptor for GnIH is the G protein-coupled receptor 147 (GPR147), which inhibits cAMP signaling. Cell bodies of GnIH neurons are located in the paraventricular nucleus (PVN) in birds and the dorsomedial hypothalamic area (DMH) in most mammals. GnIH neurons in the PVN or DMH project to the median eminence to control anterior pituitary function via GPR147 expressed in gonadotropes. Further, GnIH inhibits gonadotropin-releasing hormone (GnRH)-induced gonadotropin subunit gene transcription by inhibiting the adenylate cyclase/cAMP/PKA-dependent ERK pathway in an immortalized mouse gonadotrope cell line (LβT2 cells). GnIH neurons also project to GnRH neurons that express GPR147 in the preoptic area (POA) in birds and mammals. Accordingly, GnIH can inhibit gonadotropin synthesis and release by decreasing the activity of GnRH neurons as well as by directly inhibiting pituitary gonadotrope activity. GnIH and GPR147 can thus centrally suppress testosterone secretion and spermatogenesis by acting in the hypothalamic-pituitary-gonadal axis. GnIH and GPR147 are also expressed in the testis of birds and mammals, possibly acting in an autocrine/paracrine manner to suppress testosterone secretion and spermatogenesis. GnIH expression is also regulated by melatonin, stress, and social environment in birds and mammals. Accordingly, the GnIH-GPR147 system may play a role in transducing physical and social environmental information to regulate optimal testicular activity in birds and mammals. This review discusses central and direct inhibitory effects of GnIH and GPR147 on testosterone secretion and spermatogenesis in birds and mammals.

  16. Calystegins of Physalis alkekengi var. francheti (Solanaceae). Structure determination and their glycosidase inhibitory activities.

    PubMed

    Asano, N; Kato, A; Oseki, K; Kizu, H; Matsui, K

    1995-04-15

    calystegin B2, showed no activity against any glycosidases tested. Since calystegin B3, a 2-epimer of calystegin B2, also exhibited only a weak inhibitory activity, it was concluded that the equatorially oriented OH group at C2 is the essential feature for recognition and strong binding by the active site of glycosidases.(ABSTRACT TRUNCATED AT 400 WORDS)

  17. New Alkaloids from Green Vegetable Soybeans and Their Inhibitory Activities on the Proliferation of Concanavalin A-Activated Lymphocytes.

    PubMed

    Wang, Taoyun; Zhao, Jianping; Li, Xiaoran; Xu, Qiongming; Liu, Yanli; Khan, Ikhlas A; Yang, Shilin

    2016-03-01

    A comprehensive phytochemical study of the chemical constituents of green vegetable soybeans resulted in the isolation of two new alkaloids, soyalkaloid A, 1, and isoginsenine, 2, together with four known ones, ginsenine, 3, (1S,3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid, 4, (1R,3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid, 5, and indole-3-carboxylic acid, 6. The structures of compounds 1-6 were elucidated on the basis of spectroscopic and chemical analyses. All of the alkaloids were isolated from soybeans for the first time, and compound 1 was a new indole-type alkaloid with a novel carbocyclic skeleton. Their inhibitory activities on the proliferation of concanalin A-activated lymphocytes were assessed by CCK8 assay.

  18. Mouse mammary tumors display Stat3 activation dependent on leukemia inhibitory factor signaling

    PubMed Central

    Quaglino, Ana; Schere-Levy, Carolina; Romorini, Leonardo; Meiss, Roberto P; Kordon, Edith C

    2007-01-01

    Introduction It has been demonstrated that leukemia inhibitory factor (LIF) induces epithelium apoptosis through Stat3 activation during mouse mammary gland involution. In contrast, it has been shown that this transcription factor is commonly activated in breast cancer cells, although what causes this effect remains unknown. Here we have tested the hypothesis that locally produced LIF can be responsible for Stat3 activation in mouse mammary tumors. Methods The studies were performed in different tumorigenic and non-tumorigenic mammary cells. The expression of LIF and LIF receptor was tested by RT-PCR analysis. In tumors, LIF and Stat3 proteins were analyzed by immunohistochemistry, whereas Stat3 and extracellular signal-regulated kinase (ERK)1/2 expression and phosphorylation were studied by Western blot analysis. A LIF-specific blocking antibody was used to determine whether this cytokine was responsible for Stat3 phosphorylation induced by conditioned medium. Specific pharmacological inhibitors (PD98059 and Stat3ip) that affect ERK1/2 and Stat3 activation were used to study their involvement in LIF-induced effects. To analyze cell survival, assays with crystal violet were performed. Results High levels of LIF expression and activated Stat3 were found in mammary tumors growing in vivo and in their primary cultures. We found a single mouse mammary tumor cell line, LM3, that showed low levels of activated Stat3. Incidentally, these cells also showed very little expression of LIF receptor. This suggested that autocrine/paracrine LIF would be responsible for Stat3 activation in mouse mammary tumors. This hypothesis was confirmed by the ability of conditioned medium of mammary tumor primary cultures to induce Stat3 phosphorylation, activity that was prevented by pretreatment with LIF-blocking antibody. Besides, we found that LIF increased tumor cell viability. Interestingly, blocking Stat3 activation enhanced this effect in mammary tumor cells. Conclusion LIF is

  19. Inhibitory activity of synthesized acetylated Procyanidin B1 analogs against HeLa S3 cells proliferation.

    PubMed

    Okamoto, Syuhei; Ishihara, Sayaka; Okamoto, Taisuke; Doi, Syoma; Harui, Kota; Higashino, Yusuke; Kawasaki, Takashi; Nakajima, Noriyuki; Saito, Akiko

    2014-01-01

    Proanthocyanidins, also known as condensed tannins and/or oligomeric flavonoids, occur in many edible plants and have various interesting biological activities. Previously, we reported a synthetic method for the preparation of various procyanidins in pure form and described their biological activities. Here, we describe the synthesis of procyanidin B1 acetylated analogs and discuss their inhibition activities against HeLa S3 cell proliferation. Surprisingly, the lower-unit acetylated procyanidin B1 strongly inhibited the proliferation of HeLa S3 cells. This molecule showed much stronger inhibitory activity than did epigallocatechin-3-O-gallate (EGCG), green tea polyphenol, and dimeric compounds that included EGCG as a unit. This result suggests that the phenolic hydroxyl groups of the upper-units in flavan-3-ols are important for their inhibitory activity against cancer cell proliferation and that a hydrophobic lower unit dimer enhances this activity. PMID:24500007

  20. Regulator of G-protein signaling 18 integrates activating and inhibitory signaling in platelets.

    PubMed

    Gegenbauer, Kristina; Elia, Giuliano; Blanco-Fernandez, Alfonso; Smolenski, Albert

    2012-04-19

    Regulator of G-protein signaling 18 (RGS18) is a GTPase-activating protein for the G-α-q and G-α-i subunits of heterotrimeric G-proteins that turns off signaling by G-protein coupled receptors. RGS18 is highly expressed in platelets. In the present study, we show that the 14-3-3γ protein binds to phosphorylated serines 49 and 218 of RGS18. Platelet activation by thrombin, thromboxane A2, or ADP stimulates the association of 14-3-3 and RGS18, probably by increasing the phosphorylation of serine 49. In contrast, treatment of platelets with prostacyclin and nitric oxide, which trigger inhibitory cyclic nucleotide signaling involving cyclic AMP-dependent protein kinase A (PKA) and cyclic GMP-dependent protein kinase I (PKGI), induces the phosphorylation of serine 216 of RGS18 and the detachment of 14-3-3. Serine 216 phosphorylation is able to block 14-3-3 binding to RGS18 even in the presence of thrombin, thromboxane A2, or ADP. 14-3-3-deficient RGS18 is more active compared with 14-3-3-bound RGS18, leading to a more pronounced inhibition of thrombin-induced release of calcium ions from intracellular stores. Therefore, PKA- and PKGI-mediated detachment of 14-3-3 activates RGS18 to block Gq-dependent calcium signaling. These findings indicate cross-talk between platelet activation and inhibition pathways at the level of RGS18 and Gq. PMID:22234696

  1. Calcineurin-NFAT activation and DSCR-1 auto-inhibitory loop: how is homoeostasis regulated?

    PubMed

    Minami, Takashi

    2014-04-01

    Calcineurin-nuclear factor of activated T cells (NFAT) signalling plays a critical role not only in the immune and nervous systems, but also in cardiovascular development and pathological endothelial cell activation during angiogenesis or inflammation. Studies in NFAT-null mice demonstrated that there is high redundancy between functions of the different NFAT family members. Deletion of only one NFAT causes mild phenotypes, but compound deletions of multiple NFAT family members leads to severe abnormalities in multiple organ systems. Genome-wide transcription analysis revealed that many NFAT target genes are related to cell growth and inflammation, whereas the gene most strongly induced by NFAT in endothelial cells is an auto-inhibitory molecule, Down syndrome critical region (DSCR)-1. The NFAT-DSCR-1 signalling axis may vary depending on the cell-type or signal dosage level under the microenvironment. In the endothelium, stable expression of the DSCR-1 short isoform attenuates septic inflammatory shock, tumour growth and tumour metastasis to lung. Moreover, dysfunction of DSCR-1 and the NFAT priming kinase, DYRK1A, prevents NFAT nuclear occupancy. This change in NFAT nuclear localization is responsible for many of the features of Down syndrome. Thus, fine-tuning of the NFAT-DSCR-1 negative feedback loop may enable therapeutic manipulation in vasculopathic diseases.

  2. Lanostane triterpenoids from Ganoderma curtisii and their NO production inhibitory activities of LPS-induced microglia.

    PubMed

    Jiao, Yang; Xie, Ting; Zou, Lu-Hui; Wei, Qian; Qiu, Li; Chen, Li-Xia

    2016-08-01

    Twenty-nine lanostane triterpenoids (1-29) were obtained from the EtOH extract of fruiting bodies of the Ganoderma curtisii. Among them, compound 1 was a new lanostane triterpenoid and compounds 2-5 were isolated from the genus Ganoderma for the first time and their structures were unambiguously identified in this work. The NMR data of the four known lanostane triterpenoids (2-5) were reported for the first time because their structures were all tentatively characterized by interpreting the MS data from the methanol extract of Ganoderma lucidum or from the metabolites in rat bile after oral administration of crude extract of the fruiting bodies of G. lucidum using fragmentation rules. Their anti-inflammatory activities were tested by measuring their inhibitory effects on nitric oxide (NO) production in BV-2 microglia cells activated by lipopolysaccharide. Their IC50 values were in a range from 3.65±0.41 to 28.04±2.81μM. PMID:27335254

  3. Characterization of DicB by partially masking its potent inhibitory activity of cell division.

    PubMed

    Yang, Shaoyuan; Pei, Hairun; Zhang, Xiaoying; Wei, Qiang; Zhu, Jia; Zheng, Jimin; Jia, Zongchao

    2016-07-01

    DicB, a protein encoded by the Kim (Qin) prophage in Escherichia coli, inhibits cell division through interaction with MinC. Thus far, characterization of DicB has been severely hampered owing to its potent activity which ceases cell division and leads to cell death. In this work, through fusing maltose-binding protein to the N-terminus of DicB (MBP-DicB), we successfully expressed and purified recombinant DicB that enabled in vitro analysis for the first time. More importantly, taking advantage of the reduced inhibitory activity of MBP-DicB, we were able to study its effects on cell growth and morphology. Inhibition of cell growth by MBP-DicB was systematically evaluated using various DicB constructs, and their corresponding effects on cell morphology were also investigated. Our results revealed that the N-terminal segment of DicB plays an essential functional role, in contrast to its C-terminal tail. The N-terminus of DicB is of critical importance as even the first amino acid (following the initial Met) could not be removed, although it could be mutated. This study provides the first glimpse of the molecular determinants underlying DicB's function. PMID:27466443

  4. Calcineurin-NFAT activation and DSCR-1 auto-inhibitory loop: how is homoeostasis regulated?

    PubMed

    Minami, Takashi

    2014-04-01

    Calcineurin-nuclear factor of activated T cells (NFAT) signalling plays a critical role not only in the immune and nervous systems, but also in cardiovascular development and pathological endothelial cell activation during angiogenesis or inflammation. Studies in NFAT-null mice demonstrated that there is high redundancy between functions of the different NFAT family members. Deletion of only one NFAT causes mild phenotypes, but compound deletions of multiple NFAT family members leads to severe abnormalities in multiple organ systems. Genome-wide transcription analysis revealed that many NFAT target genes are related to cell growth and inflammation, whereas the gene most strongly induced by NFAT in endothelial cells is an auto-inhibitory molecule, Down syndrome critical region (DSCR)-1. The NFAT-DSCR-1 signalling axis may vary depending on the cell-type or signal dosage level under the microenvironment. In the endothelium, stable expression of the DSCR-1 short isoform attenuates septic inflammatory shock, tumour growth and tumour metastasis to lung. Moreover, dysfunction of DSCR-1 and the NFAT priming kinase, DYRK1A, prevents NFAT nuclear occupancy. This change in NFAT nuclear localization is responsible for many of the features of Down syndrome. Thus, fine-tuning of the NFAT-DSCR-1 negative feedback loop may enable therapeutic manipulation in vasculopathic diseases. PMID:24505143

  5. In vitro metabolism of pyripyropene A and ACAT inhibitory activity of its metabolites.

    PubMed

    Matsuda, Daisuke; Ohshiro, Taichi; Ohtawa, Masaki; Yamazaki, Hiroyuki; Nagamitsu, Tohru; Tomoda, Hiroshi

    2015-01-01

    Pyripyropene A (PPPA, 1) of fungal origin, a selective inhibitor of acyl-CoA:cholesterol acyltransferase 2 (ACAT2), proved orally active in atherogenic mouse models. The in vitro metabolites of 1 in liver microsomes and plasma of human, rabbit, rat and mouse were analyzed by ultra fast liquid chromatography and liquid chromatography/tandem mass spectrometry. In the liver microsomes from all species, successive hydrolysis occurred at the 1-O-acetyl residue, then at the 11-O-acetyl residue of 1, while the 7-O-acetyl residue was resistant to hydrolysis. Furthermore, dehydrogenation of the newly generated 11-alcoholic hydroxyl residue occurred in human and mouse-liver microsomes, while oxidation of the pyridine ring occurred in human and rabbit liver microsomes. On the other hand, hydrolysis of the 7-O-acetyl residue proceeded only in the mouse plasma. These data indicated that the in vitro metabolic profiles of 1 have subtle differences among animal species. All of the PPPA metabolites observed in liver microsomes and plasma markedly decreased ACAT2 inhibitory activity. These findings will help us to synthesize new PPPA derivatives more effective in in vivo study than 1. PMID:25005817

  6. Inhibitory activity of S-adenosylhomocysteine hydrolase inhibitors against human cytomegalovirus replication.

    PubMed

    Snoeck, R; Andrei, G; Neyts, J; Schols, D; Cools, M; Balzarini, J; De Clercq, E

    1993-07-01

    Various acyclic and carbocyclic adenosine analogues, which are apparently targeted at the S-adenosylhomocysteine (AdoHcy) hydrolase have been reported to inhibit the replication of a number of pox-, rhabdo-, paramyxo-, arena-, and reoviruses. Here we show that this activity spectrum extends to human cytomegalovirus (HCMV). Of the compounds tested, neplanocin A, 3-deazaneplanocin A, 6'-C-methylneplanocin A and 5'-noraristeromycin were found to be the most potent inhibitors of HCMV replication in vitro. Their 50% inhibitory concentration ranged from 0.05 to 1.35 micrograms/ml. In general, the anti-HCMV activity of the adenosine analogues correlated well with their affinity (Ki) for AdoHcy hydrolase, suggesting that AdoHcy hydrolase may be considered as a target enzyme for anti-HCMV agents. For four compounds (3-deazaneplanocin A, 6'-C-methylneplanocin A (isomers I and II) and 3-deazaadenosine), anti-HCMV potency was greater than could be expected solely from their interaction with AdoHcy hydrolase, suggesting that these compounds may be functioning by an additional mechanism. PMID:8215298

  7. Alkylphloroglucinol derivatives and triterpenoids with soluble epoxide hydrolase inhibitory activity from Callistemon citrinus.

    PubMed

    Khanh, Pham Ngoc; Duc, Ho Viet; Huong, Tran Thu; Son, Ninh The; Ha, Vu Thi; Van, Doan Thi; Tai, Bui Huu; Kim, Ji Eun; Jo, Ah Reum; Kim, Young Ho; Cuong, Nguyen Manh

    2016-03-01

    Phytochemical analysis of the leaves and stems of Callistemon citrinus (Curtis) Skeels led to the isolation of two new alkylphloroglucinols, gallomyrtucommulone E and F (1 and 2), along with four other known alkylphloroglucinol derivatives, gallomyrtucommulone A (3), endoperoxide G3 (4), myrtucommulone B (5), callistenone B (6) and five known triterpenoids, including betulinic acid (7), 3β-acetylmorolic acid (8), 3β-hydroxy-urs-11-en-13(28)-olide (9), diospyrolide (10) and ursolic acid (11). The structures of the natural compounds were determined from the spectroscopic evidences including 1D-/2D-NMR and HR-MS spectrometry. All the isolated compounds were assessed for the effects on the sEH inhibitory activity. The acylphloroglucinols myrtucommulone B (5)/callistenone B (6) (in mixture), and two triterpenoids, ursolic acid (11) and 3β-hydroxy-urs-11-en-13(28)-olide (9) displayed strong inhibition of sEH activity, with IC50 values of 0.7, 11.2 and 24.8 μM, respectively. PMID:26548595

  8. Regulators of complement activity mediate inhibitory mechanisms through a common C3b-binding mode.

    PubMed

    Forneris, Federico; Wu, Jin; Xue, Xiaoguang; Ricklin, Daniel; Lin, Zhuoer; Sfyroera, Georgia; Tzekou, Apostolia; Volokhina, Elena; Granneman, Joke Cm; Hauhart, Richard; Bertram, Paula; Liszewski, M Kathryn; Atkinson, John P; Lambris, John D; Gros, Piet

    2016-05-17

    Regulators of complement activation (RCA) inhibit complement-induced immune responses on healthy host tissues. We present crystal structures of human RCA (MCP, DAF, and CR1) and a smallpox virus homolog (SPICE) bound to complement component C3b. Our structural data reveal that up to four consecutive homologous CCP domains (i-iv), responsible for inhibition, bind in the same orientation and extended arrangement at a shared binding platform on C3b. Large sequence variations in CCP domains explain the diverse C3b-binding patterns, with limited or no contribution of some individual domains, while all regulators show extensive contacts with C3b for the domains at the third site. A variation of ~100° rotation around the longitudinal axis is observed for domains binding at the fourth site on C3b, without affecting the overall binding mode. The data suggest a common evolutionary origin for both inhibitory mechanisms, called decay acceleration and cofactor activity, with variable C3b binding through domains at sites ii, iii, and iv, and provide a framework for understanding RCA disease-related mutations and immune evasion. PMID:27013439

  9. Characterization of DicB by partially masking its potent inhibitory activity of cell division

    PubMed Central

    Yang, Shaoyuan; Pei, Hairun; Zhang, Xiaoying; Wei, Qiang; Zhu, Jia; Zheng, Jimin; Jia, Zongchao

    2016-01-01

    DicB, a protein encoded by the Kim (Qin) prophage in Escherichia coli, inhibits cell division through interaction with MinC. Thus far, characterization of DicB has been severely hampered owing to its potent activity which ceases cell division and leads to cell death. In this work, through fusing maltose-binding protein to the N-terminus of DicB (MBP–DicB), we successfully expressed and purified recombinant DicB that enabled in vitro analysis for the first time. More importantly, taking advantage of the reduced inhibitory activity of MBP–DicB, we were able to study its effects on cell growth and morphology. Inhibition of cell growth by MBP–DicB was systematically evaluated using various DicB constructs, and their corresponding effects on cell morphology were also investigated. Our results revealed that the N-terminal segment of DicB plays an essential functional role, in contrast to its C-terminal tail. The N-terminus of DicB is of critical importance as even the first amino acid (following the initial Met) could not be removed, although it could be mutated. This study provides the first glimpse of the molecular determinants underlying DicB's function. PMID:27466443

  10. Safety and Tolerability of the Dual 5-Alpha Reductase Inhibitor Dutasteride in the Treatment of Androgenetic Alopecia

    PubMed Central

    Choi, Gwang Seong; Kim, Joon Hyung; Oh, Shin-Young; Park, Jung-Min; Hong, Ji-Soo; Lee, Yil-Seob

    2016-01-01

    Background After the approval of dutastride for androgenic alopecia (AGA) in 2009, Korean authority required a post-marketing surveillance to obtain further data on its safety profile. Objective The objective was to monitor adverse events (AEs) of dutasteride 0.5 mg in Korean AGA male patients in a clinical practice environment. Methods Open label, multi-center, non-interventional observational study was done from July 2009 to July 2013. AGA subjects (18~41 years of age) with no experience of dutasteride were enrolled. Dosage regimen was recommended according to the prescribing information. The incidences of any AEs, serious adverse events (SAEs), and adverse drug reactions (ADRs) were evaluated. Multiple logistic regression method was used to identify risk factors related to ADRs. Effectiveness was generally evaluated by physicians. Results During study period, 712 subjects were enrolled. The subjects of 29.3±6.0 years old exposed to dutasteride for 204.7±161.5 days. One hundred and ten (15.4%) of subjects reported 138 AEs. Four subjects (0.6%) reported 5 SAEs (right radius fracture, 2 events of chronic follicular tonsillitis, influenza infection, and acute appendicitis). Sixty-six subjects (9.3%) reported 80 ADRs. Most frequent ADRs were libido decreased (9 subjects, 1.3%), dyspepsia (8 subjects, 1.1%), impotence (7 subjects, 1.0%), and fatigue (5 subjects, 0.7%). Other interested ADRs were sexual function abnormality (4 subjects, 0.6%), gynecomastia (2 subjects, 0.3%), and ejaculation disorder (1 subject, 0.1%). Most subjects (78.6%) showed overall improvement after treatment of dutasteride in the effectiveness. Conclusion Dutasteride 0.5 mg is to be well-tolerated in 18 to 41 years old AGA patients in a clinical practice environment. PMID:27489426

  11. Structure-activity relationships of vanillic acid ester analogs in inhibitory effect of antigen-mediated degranulation in rat basophilic leukemia RBL-2H3 cells.

    PubMed

    Ishimata, Nao; Ito, Hideyuki; Tai, Akihiro

    2016-08-01

    Methyl vanillate (1) showed strong degranulation inhibitory activity among vanillin derivatives tested. In order to find structure-activity relationships for developing anti-allergic agents with simple structures and potent activity, we synthesized several vanillic acid (VA) ester derivatives with C1-C4 and C8 alkyl chains and evaluated their degranulation inhibitory activities. The most active compound of VA ester derivatives was derivative 5 with a C4 straight alkyl chain, and derivative 5 exhibited approximately three-fold greater inhibitory activity than that of 1. Moreover, we designed 8 types of analogs based on 5, and we found that the minimum structure for potent degranulation inhibitory activity requires direct connection of the butyl ester moiety on the benzene ring and at least one hydroxyl group on the benzene ring. Butyl meta or para hydroxyl benzoate (10 or 11) has a simpler structure than that of 5 and exhibited more potent degranulation inhibitory activity than that of 5. PMID:27324979

  12. Phytochemical screening and evaluation of in vitro angiotensin-converting enzyme inhibitory activity of Artocarpus altilis leaf.

    PubMed

    Siddesha, Jalahalli M; Angaswamy, Nataraju; Vishwanath, Bannikuppe S

    2011-12-01

    This study investigates the effect of Artocarpus altilis leaf extracts on angiotensin-converting enzyme (ACE) activity. Among the extracts tested, hot ethanol extract exhibited a potent ACE-inhibitory activity with an IC₅₀ value of 54.08 ± 0.29 µg mL⁻¹ followed by cold ethyl acetate extract (IC₅₀ of 85.44 ± 0.85 µg mL⁻¹). In contrast, the hot aqueous extracts showed minimum inhibition with the IC₅₀ value of 765.52 ± 11.97 µg mL⁻¹ at the maximum concentration tested. Further, the phytochemical analysis indicated the varied distribution of tannins, phenolics, glycosides, saponins, steroids, terpenoids and anthraquinones in cold and hot leaf extracts. The correlation between the phytochemical analysis and ACE-inhibitory activity suggests that the high content of glycosidic and phenolic compounds could be involved in exerting ACE-inhibitory activity. In conclusion, this study supports the utilisation of A. altilis leaf in the folk medicine for the better treatment of hypertension. Further studies on isolation and characterisation of specific ACE-inhibitory molecule(s) from ethyl acetate, ethanol and methanol extracts of A. altilis leaf would be highly interesting.

  13. Douglas-fir root-associated microorganisms with inhibitory activity towards fungal plant pathogens and human bacterial pathogens.

    PubMed

    Axelrood, P E; Clarke, A M; Radley, R; Zemcov, S J

    1996-07-01

    A microbial culture collection composed of 1820 bacterial strains, including 298 actinomycete strains, was established from the roots of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings harvested from conifer nurseries and forest sites. Two hundred and thirty-four strains inhibited the growth of Fusarium, Cylindrocarpon, and (or) Pythium spp. in in vitro assays. A significantly greater proportion of bacterial strains from actinomycete genera exhibited antifungal properties compared with bacterial strains from nonactinomycete genera. Eighty-nine percent of identified inhibitory strains were Streptomyces, Streptoverticillium, Bacillus, Pseudomonas, or Burkholderia species. The actinomycete species were isolated almost exclusively from forest seedlings. Recovery of inhibitory strains representing 29 microbial species was enhanced using a variety of methods to isolate microorganisms from the roots of seedlings from nursery and forest sites. Bacterial strains (including actinomycete strains) with antifungal activity were tested for in vitro growth inhibition of six clinical human bacterial pathogens (Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Proteus mirabilis, and Pseudomonas aeruginosa). Forty-eight percent of the tested strains inhibited one or more human pathogens, Inhibitory activity towards fungal and bacterial pathogens was strain specific, not species specific, and many inhibitory strains exhibited broad-spectrum activity. Strains with antifungal activity against several conifer root pathogens were also more likely to inhibit multiple species of clinical bacterial pathogens.

  14. Determination of antioxidant capacity and a-amylase inhibitory activity of the essential oils from citronella grass and lemongrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of the present study was to determine the antioxidant capacity of and in vitro a-amylase inhibitory activity of the essential oils extracted from citronella grass and lemongrass. The chemical composition of the extracted essential oils was determined by GC-MS. The antioxidant capacity ...

  15. Inhibitory effect of putranjivain A on allergic inflammation through suppression of mast cell activation

    SciTech Connect

    Kim, Hui-Hun; Park, Seung-Bin; Lee, Soyoung; Kwon, Taeg Kyu; Shin, Tae-Yong; Park, Pil-Hoon; Lee, Seung-Ho; Kim, Sang-Hyun

    2014-02-01

    A great number of people are suffering from allergic inflammatory disease such as asthma, atopic dermatitis, and sinusitis. Therefore discovery of drugs for the treatment of these diseases is an important subject in human health. Putranjivain A (PJA), member of ellagitannin, is known to possess beneficial effects including anti-cancer and anti-viral activities. The aim of the present study was to elucidate whether PJA modulates the allergic inflammatory reaction and to study its possible mechanisms of action using mast cell-based in vitro and in vivo models. The study was performed in anaphylaxis mouse model and cultured mast cells. PJA inhibited the expression of pro-inflammatory cytokines in immunoglobulin E-stimulated mast cells. PJA reduced this expression by inhibiting nuclear factor (NF)-κB and nuclear factor of activated T cell. The oral administration of PJA reduced systemic and cutaneous anaphylaxis, the release of serum histamine, and the expression of the histamine H{sub 1} receptor. In addition, PJA attenuated the activation of mast cells. PJA inhibited the release of histamine from various types of mast cells by the suppression of intracellular calcium. The inhibitory activity of PJA on the allergic reaction was similar to that of disodium cromoglycate, a known anti-allergic drug. These results suggest that PJA can facilitate the prevention or treatment of allergic inflammatory diseases mediated by mast cells. - Highlights: • PJA reduced the degranulation of mast cells. • PJA inhibited the production of inflammatory cytokines. • The effect of PJA on allergic reaction was comparable to the DSCG. • PJA might be a candidate for the treatment of allergic inflammatory diseases.

  16. Inhibitory mechanism of an extract of Althaea officinalis L. on endothelin-1-induced melanocyte activation.

    PubMed

    Kobayashi, Akemi; Hachiya, Akira; Ohuchi, Atsushi; Kitahara, Takashi; Takema, Yoshinori

    2002-02-01

    It is known that expression of endothelin-1 (ET-1) increases in the epidermis after UVB irradiation, and that this plays an important role during the induction of pigmentation both as a mitogen and as a melanogen for normal human melanocytes (NHMC). When ET-1 acts on NHMC via the endothelin B receptor (ET(B)R) on their cell surface, mobilization of intracellular calcium is induced, which is followed by activation of Raf-1 located upstream of mitogen activated protein kinase (MAPK). We have continued the search for new agent which inhibit this calcium mobilization and we have found that an extract of Althaea officinalis L. has such an action. In this study, we investigated the precise inhibitory mechanism of this botanical extract on the ET-1-induced activation of melanocytes. Treatment of NHMC with this extract abrogated the stimulatory effect of ET-1 on proliferation and also on activation of MAPK in the intracellular signal transduction pathway, but did not affect the binding of ET-1 to the ET(B)R or the production of Inositol 1,4,5-Trisphosphate (IP3). Further, when this extract was used to treat normal human keratinocytes (NHKC), secretion of ET-1 by those cells was reduced. Taken together, these findings indicate that an extract of A. officinalis inhibits both the secretion of ET-1 from NHKC and the action of ET-1 on NHMC mainly by suppressing the ET-1-induced calcium mobilization without the modification of IP3 production, which in turn suggests that this extract is a useful ingredient for a whitening agent.

  17. Inhibitory and Cytotoxic Activities of Chrysin on Human Breast Adenocarcinoma Cells by Induction of Apoptosis

    PubMed Central

    Samarghandian, Saeed; Azimi-Nezhad, Mohsen; Borji, Abasalt; Hasanzadeh, Malihe; Jabbari, Farahzad; Farkhondeh, Tahereh; Samini, Mohammad

    2016-01-01

    Objectives: Chrysin, an active natural bioflavonoid found in honey and many plant extracts, was first known for its antioxidant and anti-inflammatory effects. The fact that antioxidants have several inhibitory effects against different diseases, such as cancer, led to search for food rich in antioxidants. In this study, we investigated the antiproliferative and apoptotic effects of chrysin on the cultured human breast cancer cells (MCF-7). Materials and Methods: Cells were cultured in Roswell Park Memorial Institute medium and treated with different chrysin concentrations for three consecutive days. Cell viability was quantitated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The percentage of apoptotic cells was determined by flow cytometry using Annexin V-fluorescein isothiocyanate. Results: The MTT assay showed that chrysin had an antiproliferative effect on MCF-7 cells in a dose- and time-dependent manner. The 50% cell growth inhibition values for chrysin against MCF-7 cells were 19.5 and 9.2 μM after 48 and 72 h, respectively. Chrysin induced apoptosis in MCF-7 cells as determined by flow cytometry. Chrysin inhibits the growth of the breast cancer cells by inducing cancer cell apoptosis which may, in part, explain its anticancer activity. Conclusion: This study shows that chrysin could also be considered as a promising chemotherapeutic agent and anticancer activity in treatment of the breast cancer cells in future. SUMMARY Chrysin had an antiproliferative effect on human breast cancer cells (MCF-7) cells in a dose- and time-dependent mannerChrysin induced apoptosis in MCF-7 cells, as determined by flow cytometryChrysin inhibits the growth of the breast cancer cells by inducing cancer cell apoptosisChrysin may have anticancer activity. Abbreviations used: Human breast cancer cells (MCF-7), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), phosphate-buffered saline (PBS), normal fibroblast mouse (L929). PMID

  18. In vitro α-amylase and α-glucosidase inhibitory effects and cytotoxic activity of Albizia antunesiana extracts

    PubMed Central

    Chipiti, Talent; Ibrahim, Mohammed Auwal; Singh, Moganavelli; Islam, Md. Shahidul

    2015-01-01

    Context: Diabetes mellitus is a chronic disease, and its incidence is tremendously increasing globally. Decreasing postprandial hyperglycemia by retarding glucose absorption through inhibiting carbohydrates digesting enzymes (α-amylase and α-glucosidase) is one of many approaches used for the management of this disease. Objectives: The leaf and root aqueous and ethanol extracts of Albizia antunesiana were investigated for α-amylase and α-glucosidase inhibitory and cytotoxic activity in vitro. Materials and Methods: The α-amylase and α-glucosidase activities were measured in the presence of aqueous and ethanol extracts of the plant parts using starch and p-nitrophenyl-D-glucopyranoside as substrates respectively. Furthermore, cytotoxic effects of the extracts were investigated on HEK (human embryonic kidney) 293 cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay. Results: The results showed that ethanolic root extract of A. antunesiana had mild α-amylase and strong α-glucosidase inhibitory activity with half-maximal inhibitory concentration values of 30.68 and 4.35 µg/mL, respectively. The aqueous root extract showed mild α-glucosidase but no α-amylase inhibitory activity. Cytotoxicity studies on the extracts using the MTT assay revealed that the ethanolic (leaf and root) extracts were relatively nontoxic at tested concentrations on the HEK 293 cell lines. However, the aqueous extracts (leaf and root) were cytotoxic at concentrations above 50 µg/mL. Conclusion: Data from this study suggest that the ethanolic root extract of A. antunesiana possess in vitro α-amylase and α-glucosidase inhibitory activities and are not cytotoxic at least in an in vitro condition. PMID:26664010

  19. Pretreatment of garlic powder using sweep frequency ultrasound and single frequency countercurrent ultrasound: optimization and comparison for ACE inhibitory activities.

    PubMed

    Ma, Haile; Huang, Liurong; Peng, Lei; Wang, Zhenbin; Yang, Qiaorong

    2015-03-01

    The sweep frequency ultrasound (SFU) and single frequency countercurrent ultrasound (SFCU) pretreatments were modeled and compared based on production of angiotensin I-converting enzyme (ACE) inhibitory peptides from garlic hydrolysates. Two mathematical models were developed to show the effect of each variable and their combinatorial interactions on ACE inhibitory activity. The optimum levels of the parameters in SFU were determined using uniform design, which revealed these as follows: total ultrasonic time 1.5 h, on-time of pulse 18 s and off-time of pulse 3 s. Under optimized conditions, the experimental values of SFU and SFCU were 65.88% and 67.78%, which agreed closely with the predicted values of 63.44% and 67.33%. The SFU and SFCU pretreatments both resulted in higher ACE inhibitory activity compared with untreated garlic (p<0.05). However, there were no significant differences in the ACE inhibitory activities and IC₅₀ values obtained from SFCU and SFU pretreatments under optimum conditions (p>0.05).

  20. Retroviral reverse transcriptase inhibitory activity in Thai herbs and spices: screening with Moloney murine leukemia viral enzyme.

    PubMed

    Suthienkul, O; Miyazaki, O; Chulasiri, M; Kositanont, U; Oishi, K

    1993-12-01

    Fifty-seven Thai herbs and spices were examined for their retroviral reverse transcriptase inhibitory activity. All herbs and spices were extracted with hot-water and methanol. Reverse transcriptase inhibitory activity of the extracts was determined by using Moloney Murine Leukemia Virus reverse transcriptase (M-MuLV-RT) reacted with 3H-dTTP and radioactivity measured with a scintillation counter. Eighty-one per cent (46/57) of hot-water extracts and 54% (31/57) of methanol extracts showed inhibitory activities. At a concentration of 125 micrograms/ml, 13% (6/46) of hot-water extracts, namely Eugenia caryophyllus Bullock et Harrison, Phyllanthus urinaria Linn., Terminalia belerica Roxb., Nelumbo nucifera Gaertn., Psidium guajava Linn. and Lawsonia inermis Linn., had a relative inhibitory ratio (IR) over 50%. They showed ratios of 100%, 91%, 75%, 74%, 61% and 60%, respectively. For methanol extracts, only 10% (3/31) had IR values over 50%. They were T. belerica, E. caryophyllus and N. nucifera which exhibited IR values of 83%, 54% and 54%, respectively. PMID:7524165

  1. Systematic synthesis of galloyl-substituted procyanidin B1 and B2, and their ability of DPPH radical scavenging activity and inhibitory activity of DNA polymerases.

    PubMed

    Saito, Akiko; Mizushina, Yoshiyuki; Ikawa, Hiroshi; Yoshida, Hiromi; Doi, Yuki; Tanaka, Akira; Nakajima, Noriyuki

    2005-04-15

    Six galloyl-substituted procyanidin B1 and B2, 3-O-gallate, 3''-O-gallate, and 3,3''-di-O-gallate, were systematically synthesized with the condensation method using TMSOTf as a catalyst. Their ability of DPPH radical scavenging activity and DNA polymerase inhibitory activity were also investigated. The results indicated that the galloyl group of these compounds is very important for both activities. 3,3''-Di-O-gallate dimers acted as strong inhibitor against DNA polymerase alpha and beta, whereas the desgalloyl and monogalloyl compounds did not exhibit any appreciable inhibitory activity against the DNA polymerase beta.

  2. P-glycoprotein inhibitory activity of two phenolic compounds, (-)-syringaresinol and tricin from Sasa borealis.

    PubMed

    Jeong, Yeon Hee; Chung, Soo Yeon; Han, Ah-Reum; Sung, Min Kyung; Jang, Dae Sik; Lee, Jun; Kwon, Youngjoo; Lee, Hwa Jeong; Seo, Eun-Kyoung

    2007-01-01

    (-)-Syringaresinol and tricin, isolated from the AcOEt-soluble extract of the whole plants of Sasa borealis (Gramineae), showed inhibitory effects on the P-glycoprotein in adriamycin-resistant human breast cancer cells, MCF-7/ADR. PMID:17256728

  3. Inhibitory effects of docosyl p-coumarate on DNA topoisomerase activity and human cancer cell growth.

    PubMed

    Mizushina, Yoshiyuki; Nishimura, Katsumi; Takenaka, Yukiko; Takeuchi, Toshifumi; Sugawara, Fumio; Yoshida, Hiromi; Tanahashi, Takao

    2010-10-01

    We previously found six compounds of alkyl p-coumarates from a composite plant Artemisia annua L., and chemically synthesized these compounds (cis-isomer of C20, C22 and C24, and trans-isomer of C20, C22 and C24 of p-coumarates are compounds 1-6, respectively). This report describes the inhibitory activities of these alkyl p-coumarates against DNA polymerase (pol), DNA topoisomerase (topo), and human cancer cell growth. Among the compounds tested, compounds 1 and 4 weakly inhibited repair-related pol beta activity, but no compound influenced the activity of replicative pol alpha. Compounds 4-6 and compounds 2 and 5 were potent inhibitors of human topos I and II, respectively. Compounds 2, 4, 5 and 6 also suppressed the growth of human colon carcinoma cell line, HCT116, with or without p53, suggesting that cell growth inhibition had the same tendency as the inhibition of topos rather than pols. Compound 5 (docosyl p-coumarate), which was the strongest inhibitor of topo II and cancer cell growth in the compounds tested, halted HCT116 p53(+/+) cells in G2/M phases, and induced apoptosis, although this compound did not affect the cell cycle of HCT116 p53(-/-) cells. These results suggest that the effect of p53-dependent cell cycle arrest may be effective for topo inhibition by com-pound 5. From these findings, the action mode of alkyl p-coumarates as an anti-cancer agent is discussed. PMID:20811721

  4. Leukemia inhibitory factor promotes tumor growth and metastasis in human osteosarcoma via activating STAT3.

    PubMed

    Liu, Bin; Lu, Yi; Li, Jinzhi; Liu, Yanping; Liu, Jian; Wang, Weiguo

    2015-10-01

    The leukemia inhibitory factor (LIF) has been demonstrated to be an oncogene and participated in multiple procedures during the initiation and progression of many human malignancies. However, the role of LIF in osteosarcoma is still largely unknown. Here, we performed a series of in vitro and in vivo experiments to investigate the expression and biological functions of LIF in osteosarcoma. Compared to that in the non-cancerous tissues, LIF was significantly overexpressed in a panel of 68 osteosarcoma samples (p < 0.0001). Moreover, the overexpression of LIF was significantly correlated with advanced tumor stage, larger tumor size, and shorter overall survival. In addition, knockdown of LIF notably suppressed the proliferation and invasion of osteosarcoma via blocking the STAT3 signal pathway; in contrast, treatment with the recombinant LIF protein significantly promoted the growth and invasion of osteosarcoma through enhancing the phosphorylation of STAT3, which can be partially neutralized by the STAT3 inhibitor, HO-3867. In conclusion, we demonstrated that LIF was frequently overexpressed in osteosarcoma, which could promote the growth and invasion through activating the STAT3 pathway. Our findings proposed that LIF might be a potent therapeutic target for osteosarcoma.

  5. Anoctamin Calcium-Activated Chloride Channels May Modulate Inhibitory Transmission in the Cerebellar Cortex.

    PubMed

    Zhang, Weiping; Schmelzeisen, Steffen; Parthier, Daniel; Frings, Stephan; Möhrlen, Frank

    2015-01-01

    Calcium-activated chloride channels of the anoctamin (alias TMEM16) protein family fulfill critical functions in epithelial fluid transport, smooth muscle contraction and sensory signal processing. Little is known, however, about their contribution to information processing in the central nervous system. Here we examined the recent finding that a calcium-dependent chloride conductance impacts on GABAergic synaptic inhibition in Purkinje cells of the cerebellum. We asked whether anoctamin channels may underlie this chloride conductance. We identified two anoctamin channel proteins, ANO1 and ANO2, in the cerebellar cortex. ANO1 was expressed in inhibitory interneurons of the molecular layer and the granule cell layer. Both channels were expressed in Purkinje cells but, while ANO1 appeared to be retained in the cell body, ANO2 was targeted to the dendritic tree. Functional studies confirmed that ANO2 was involved in a calcium-dependent mode of ionic plasticity that reduces the efficacy of GABAergic synapses. ANO2 channels attenuated GABAergic transmission by increasing the postsynaptic chloride concentration, hence reducing the driving force for chloride influx. Our data suggest that ANO2 channels are involved in a Ca2+-dependent regulation of synaptic weight in GABAergic inhibition. Thus, in balance with the chloride extrusion mechanism via the co-transporter KCC2, ANO2 appears to regulate ionic plasticity in the cerebellum.

  6. Sulforaphane Analogues with Heterocyclic Moieties: Syntheses and Inhibitory Activities against Cancer Cell Lines.

    PubMed

    Shi, Ye-Hui; Dai, Dong-Fang; Li, Jing; Dong, Yan-Wei; Jiang, Yin; Li, Huan-Gong; Gao, Yuan; Chong, Chuan-Ke; Li, Hui-Ying; Chu, Xiao-Qian; Yang, Cheng; Zhang, Quan; Tong, Zhong-Sheng; Bai, Cui-Gai; Chen, Yue

    2016-01-01

    Recent studies have shown that sulforaphane (SFN) selectively inhibits the growth of ALDH⁺ breast cancer stem-like cells.Herein, a series of SFN analogues were synthesized and evaluated against breast cancer cell lines MCF-7 and SUM-159, and the leukemia stem cell-like cell line KG-1a. These SFN analogues were characterized by the replacement of the methyl group with heterocyclic moieties, and the replacement of the sulfoxide group with sulfide or sulfone. A growth inhibitory assay indicated that the tetrazole analogs 3d, 8d and 9d were significantly more potent than SFN against the three cancer cell lines. Compound 14c, the water soluble derivative of tetrazole sulfide 3d, demonstrated higher potency against KG-1a cell line than 3d. SFN, 3d and 14c significantly induced the activation of caspase-3, and reduced the ALDH⁺ subpopulation in the SUM159 cell line, while the marketed drug doxrubicin(DOX) increased the ALDH⁺ subpopulation. PMID:27110751

  7. Leukemia inhibitory factor promotes tumor growth and metastasis in human osteosarcoma via activating STAT3.

    PubMed

    Liu, Bin; Lu, Yi; Li, Jinzhi; Liu, Yanping; Liu, Jian; Wang, Weiguo

    2015-10-01

    The leukemia inhibitory factor (LIF) has been demonstrated to be an oncogene and participated in multiple procedures during the initiation and progression of many human malignancies. However, the role of LIF in osteosarcoma is still largely unknown. Here, we performed a series of in vitro and in vivo experiments to investigate the expression and biological functions of LIF in osteosarcoma. Compared to that in the non-cancerous tissues, LIF was significantly overexpressed in a panel of 68 osteosarcoma samples (p < 0.0001). Moreover, the overexpression of LIF was significantly correlated with advanced tumor stage, larger tumor size, and shorter overall survival. In addition, knockdown of LIF notably suppressed the proliferation and invasion of osteosarcoma via blocking the STAT3 signal pathway; in contrast, treatment with the recombinant LIF protein significantly promoted the growth and invasion of osteosarcoma through enhancing the phosphorylation of STAT3, which can be partially neutralized by the STAT3 inhibitor, HO-3867. In conclusion, we demonstrated that LIF was frequently overexpressed in osteosarcoma, which could promote the growth and invasion through activating the STAT3 pathway. Our findings proposed that LIF might be a potent therapeutic target for osteosarcoma. PMID:26271643

  8. Storkhead box 2 and melanoma inhibitory activity promote oral squamous cell carcinoma progression

    PubMed Central

    Sasahira, Tomonori; Nishiguchi, Yukiko; Fujiwara, Rina; Kurihara, Miyako; Kirita, Tadaaki; Bosserhoff, Anja Katrin; Kuniyasu, Hiroki

    2016-01-01

    Background Storkhead box protein 2 (STOX2) is a transcriptional factor associated with pre-eclampsia with fetal growth restriction. We recently reported that melanoma inhibitory activity (MIA) promotes oral squamous cell carcinoma (OSCC) progression. However, the relationship between STOX2 and MIA remains unknown in malignancies. Methods We used immunohistochemistry and PCR to investigate MIA and STOX2 expression in OSCC. We also performed functional analysis in human OSCC cells. Results MIA and STOX2 mRNA levels were higher in OSCCs than in normal oral epithelial cells, and upregulation of STOX2 was significantly correlated with overexpression of MIA. Immunostaining for STOX2 was associated with nodal metastasis (P = 0.0002) and MIA expression (P < 0.0001). Furthermore, MIA expression (P = 0.0035) and STOX2 expression (P = 0.0061) were associated with poor outcome in OSCCs. In vitro analysis using OSCC cells revealed that MIA increased expression of STOX2 by paracrine manner. Moreover, STOX2 accelerated OSCC cell growth, invasion, suppressed apoptosis, and enhanced resistance to paclitaxel, cisplatin, and 5-FU. Conclusions Our results suggest that MIA-STOX2 signaling may be a useful diagnostic and therapeutic target in OSCCs. PMID:27050375

  9. Anoctamin Calcium-Activated Chloride Channels May Modulate Inhibitory Transmission in the Cerebellar Cortex.

    PubMed

    Zhang, Weiping; Schmelzeisen, Steffen; Parthier, Daniel; Frings, Stephan; Möhrlen, Frank

    2015-01-01

    Calcium-activated chloride channels of the anoctamin (alias TMEM16) protein family fulfill critical functions in epithelial fluid transport, smooth muscle contraction and sensory signal processing. Little is known, however, about their contribution to information processing in the central nervous system. Here we examined the recent finding that a calcium-dependent chloride conductance impacts on GABAergic synaptic inhibition in Purkinje cells of the cerebellum. We asked whether anoctamin channels may underlie this chloride conductance. We identified two anoctamin channel proteins, ANO1 and ANO2, in the cerebellar cortex. ANO1 was expressed in inhibitory interneurons of the molecular layer and the granule cell layer. Both channels were expressed in Purkinje cells but, while ANO1 appeared to be retained in the cell body, ANO2 was targeted to the dendritic tree. Functional studies confirmed that ANO2 was involved in a calcium-dependent mode of ionic plasticity that reduces the efficacy of GABAergic synapses. ANO2 channels attenuated GABAergic transmission by increasing the postsynaptic chloride concentration, hence reducing the driving force for chloride influx. Our data suggest that ANO2 channels are involved in a Ca2+-dependent regulation of synaptic weight in GABAergic inhibition. Thus, in balance with the chloride extrusion mechanism via the co-transporter KCC2, ANO2 appears to regulate ionic plasticity in the cerebellum. PMID:26558388

  10. Anoctamin Calcium-Activated Chloride Channels May Modulate Inhibitory Transmission in the Cerebellar Cortex

    PubMed Central

    Parthier, Daniel; Frings, Stephan; Möhrlen, Frank

    2015-01-01

    Calcium-activated chloride channels of the anoctamin (alias TMEM16) protein family fulfill critical functions in epithelial fluid transport, smooth muscle contraction and sensory signal processing. Little is known, however, about their contribution to information processing in the central nervous system. Here we examined the recent finding that a calcium-dependent chloride conductance impacts on GABAergic synaptic inhibition in Purkinje cells of the cerebellum. We asked whether anoctamin channels may underlie this chloride conductance. We identified two anoctamin channel proteins, ANO1 and ANO2, in the cerebellar cortex. ANO1 was expressed in inhibitory interneurons of the molecular layer and the granule cell layer. Both channels were expressed in Purkinje cells but, while ANO1 appeared to be retained in the cell body, ANO2 was targeted to the dendritic tree. Functional studies confirmed that ANO2 was involved in a calcium-dependent mode of ionic plasticity that reduces the efficacy of GABAergic synapses. ANO2 channels attenuated GABAergic transmission by increasing the postsynaptic chloride concentration, hence reducing the driving force for chloride influx. Our data suggest that ANO2 channels are involved in a Ca2+-dependent regulation of synaptic weight in GABAergic inhibition. Thus, in balance with the chloride extrusion mechanism via the co-transporter KCC2, ANO2 appears to regulate ionic plasticity in the cerebellum. PMID:26558388

  11. Alpha-amylase inhibitory activity and sterol composition of the marine algae, Sargassum glaucescens

    PubMed Central

    Payghami, Nasrin; Jamili, Shahla; Rustaiyan, Abdolhossein; Saeidnia, Soodabeh; Nikan, Marjan; Gohari, Ahmad Reza

    2015-01-01

    Background: Sargassum species (phaeophyceae) are economically important brown algae in southern parts of Iran. Sargassum is mainly harvested as a row material in alginate production industries and is a source of plant foods or plant bio-stimulants even a component of animal foods. Objective: In this study, Sargassum glaucescens, collected from the seashore of Chabahar, was employed for phytochemical and biological evaluations. Materials and Methods: For that purpose, the dried algae was extracted by methanol and subjected to different chromatographic separation methods. Results: Six sterols, fucosterol (1), 24(S)-hydroxy-24-vinylcholesterol (2), 24(R)-hydroxy-24-vinylcholesterol (3), stigmasterol (4), β-sitosterol (5) and cholesterol (6) were identified by spectroscopic methods including 1H-NMR, 13C-NMR and mass spectroscopy. In vitro alpha-amylase inhibitory test was performed on the methanolic extract and the results revealed a potent inhibition (IC50 = 8.9 ± 2.4 mg/mL) of the enzyme compared to acarbose as a positive control. Conclusion: Various biological activities and distribution of sterols in Sargassum genus have been critically reviewed here. The results concluded that these algae are a good candidate for further anti-diabetic investigations in animals and human. PMID:26692744

  12. The inhibitory activity of linalool against the filamentous growth and biofilm formation in Candida albicans.

    PubMed

    Hsu, Chih-Chieh; Lai, Wen-Lin; Chuang, Kuei-Chin; Lee, Meng-Hwan; Tsai, Ying-Chieh

    2013-07-01

    Candida spp. are part of the natural human microbiota, but they also represent important opportunistic human pathogens. Biofilm-associated Candida albicans infections are clinically relevant due to their high levels of resistance to traditional antifungal agents. In this study, we investigated the ability of linalool to inhibit the formation of C. albicans biofilms and reduce existing C. albicans biofilms. Linalool exhibited antifungal activity against C. albicans ATCC 14053, with a minimum inhibitory concentration (MIC) of 8 mM. Sub-MIC concentrations of linalool also inhibited the formation of germ tubes and biofilms in that strain. The defective architecture composition of C. albicans biofilms exposed to linalool was characterized by scanning electron microscopy. The expression levels of the adhesin genes HWP1 and ALS3 were downregulated by linalool, as assessed by real-time RT-PCR. The expression levels of CYR1 and CPH1, which encode components of the cAMP-PKA and MAPK hyphal formation regulatory pathways, respectively, were also suppressed by linalool, as was the gene encoding their upstream regulator, Ras1. The expression levels of long-term hyphae maintenance associated genes, including UME6, HGC1, and EED1, were all suppressed by linalool. These results indicate that linalool may have therapeutic potential in the treatment of candidiasis associated with medical devices because it interferes with the morphological switch and biofilm formation of C. albicans.

  13. Inhibitory Effects of Glycyrrhetinic Acid on DNA Polymerase and Inflammatory Activities

    PubMed Central

    Ishida, Tsukasa; Mizushina, Yoshiyuki; Yagi, Saori; Irino, Yasuhiro; Nishiumi, Shin; Miki, Ikuya; Kondo, Yasuyuki; Mizuno, Shigeto; Yoshida, Hiromi; Azuma, Takeshi; Yoshida, Masaru

    2012-01-01

    We investigated the inhibitory effect of three glycyrrhizin derivatives, such as Glycyrrhizin (compound 1), dipotassium glycyrrhizate (compound 2) and glycyrrhetinic acid (compound 3), on the activity of mammalian pols. Among these derivatives, compound 3 was the strongest inhibitor of mammalian pols α, β, κ, and λ, which belong to the B, A, Y, and X families of pols, respectively, whereas compounds 1 and 2 showed moderate inhibition. Among the these derivatives tested, compound 3 displayed strongest suppression of the production of tumor necrosis factor-α (TNF-α) induced by lipopolysaccharide (LPS) in a cell-culture system using mouse macrophages RAW264.7 and peritoneal macrophages derived from mice. Moreover, compound 3 was found to inhibit the action of nuclear factor-κB (NF-κB) in engineered human embryonic kidney (HEK) 293 cells. In addition, compound 3 caused greater reduction of 12-O-tetradecanoylphorbol-13-acetate-(TPA-) induced acute inflammation in mouse ear than compounds 1 and 2. In conclusion, this study has identified compound 3, which is the aglycone of compounds 1 and 2, as a promising anti-inflammatory candidate based on mammalian pol inhibition. PMID:21785649

  14. Inhibitory activities against rice pathogens of 8-hydroxy-2,4,6-octatriynamide from Agrocybe sp.

    PubMed

    Zheng, Yongbiao; Xu, Xiaoping; Wu, Yabin

    2016-03-01

    8-Hydroxy-2,4,6-octatriynamide, a natural polyacetylene with inhibitory activities against rice pathogens, was isolated from the liquid fermentation broth of strain Agrocybe sp. YB2005 during screening for new natural chemical agents to control rice pathogens. 8-hydroxy-2,4,6-octatriynamide was purified by consecutive chromatography over a Cl8 reversed phase silica gel, sephadex LH-20 and silica gel. The chemical structure of 8-hydroxy-2,4,6-octatriynamide was elucidated through spectroscopic analyses, including 1D- and 2D-NMR, ESI mass spectrometry and X-ray single crystal diffraction. Bioassays showed that 8-hydroxy-2,4,6-octatriynamide could significantly inhibit growth of Xanthomonas oryzae with an MIC of 53.1 μM in a 96-well plate and the growth of Rhizoctonia solani at 1.02 mM in a 24-well plate. When rice leaves were inoculated with Magnaporthe grisea and cultured in artificial nutrition liquid containing 0.34 mM 8-hydroxy-2,4,6-octatriynamide, no rice blast was observed. The present study implied that 8-hydroxy-2,4,6-octatriynamide could be a candidate agent against rice pathogens. PMID:26861586

  15. [Inhibitory effect of imperatorin and isoimperatorin on activity of cytochrome P450 enzyme in human and rat liver microsomes].

    PubMed

    Cao, Yan; Zhong, Yu-Huan; Yuan, Mei; Li, Hua; Zhao, Chun-Jie

    2013-04-01

    Imperatorin (IM) and isoimperatorin (ISOIM) are major active components of common herbal medicines from Umbelliferae plants, and widely used in clinic. This article studies the inhibitory effect of IM and ISOIM on the activity of cytochrome P450 (CYP) enzyme, and assesses their potential drug-drug interaction. IM and ISOIM were incubated separately with human or rat liver microsomes for 30 min, with phenacetin, bupropion, tolbutamide, S-mephenytoin, dextromethorphan and midazolam as probe substrates. Metabolites of the CYP probe substrates were determined by LC-MS/MS, and IC50 values were calculated to assess the inhibitory effect of the two drugs on human CYP1A2, 2B6, 2C9, 2C19, 2D6 and 3A4 enzymes, as well as on rat CYP1A2, 2B6, 2D2 and 3A1/2, and grade their inhibitory intensity. In human liver microsomes, IM and ISOIM showed different inhibitory effects on all of the six CYP isoenzymes. They were strong inhibitors for 1A2 and 2B6. The IC50 values were 0.05 and 0.20 micromol x L(-1) for 1A2, and 0.18 and 1.07 micromol x L(-1) for 2B6, respectively. They also showed moderate inhibitory effect on 2C19, and weak effect on 2C9, 2D6 and 3A4. In rat liver microsomes, IM and ISOIM were identified as moderate inhibitors for 1A2, with IC50 values of 1.95 and 2.98 micromol x L(-1). They were moderate and weak inhibitors for 2B6, with IC50 values of 6.22 and 21.71 micromol x L(-1), respectively. They also had weaker inhibitory effect on 2D2 and 3A1/2. The results indicated that IM and ISOIM had extensive inhibitory effects on human CYP enzymes. They are strong inhibitors of CYP1 A2 and 2B6 enzymes. However, it is worth noting the interaction arising from the inhibitory effect of CYP enzymes in clinic.

  16. Prediction of Inhibitory Activity of Epidermal Growth Factor Receptor Inhibitors Using Grid Search-Projection Pursuit Regression Method

    PubMed Central

    Du, Hongying; Hu, Zhide; Bazzoli, Andrea; Zhang, Yang

    2011-01-01

    The epidermal growth factor receptor (EGFR) protein tyrosine kinase (PTK) is an important protein target for anti-tumor drug discovery. To identify potential EGFR inhibitors, we conducted a quantitative structure–activity relationship (QSAR) study on the inhibitory activity of a series of quinazoline derivatives against EGFR tyrosine kinase. Two 2D-QSAR models were developed based on the best multi-linear regression (BMLR) and grid-search assisted projection pursuit regression (GS-PPR) methods. The results demonstrate that the inhibitory activity of quinazoline derivatives is strongly correlated with their polarizability, activation energy, mass distribution, connectivity, and branching information. Although the present investigation focused on EGFR, the approach provides a general avenue in the structure-based drug development of different protein receptor inhibitors. PMID:21811593

  17. Iridoids from Fraxinus excelsior with adipocyte differentiation-inhibitory and PPARalpha activation activity.

    PubMed

    Bai, Naisheng; He, Kan; Ibarra, Alvin; Bily, Antoine; Roller, Marc; Chen, Xiaozhuo; Rühl, Ralph

    2010-01-01

    Two new secoiridoid glucosides, excelsides A (1) and B (2), were isolated from the seeds of Fraxinus excelsior. Their structures were elucidated as (2S,4S,3E)-methyl 3-ethylidene-4-(2-methoxy-2-oxoethyl)-2-[(6-O-beta-D-glucopyranosyl-beta-d-glucopyranosyl)oxy]-3,4-dihydro-2H-pyran-5-carboxylate and (2S,4S,3E)-methyl 3-ethylidene-4-{2-[2-(4-hydroxyphenyl)ethyl]oxy-2-oxoethyl}-2-[(6-O-beta-d-glucopyranosyl-beta-d-glucopyranosyl)oxy]-3,4-dihydro-2H-pyran-5-carboxylate, respectively, on the basis of NMR and MS data. Eight known compounds were identified as nuzhenide (3), GI3 (4), GI5 (5), ligstroside (6), oleoside 11-methyl ester (7), oleoside dimethyl ester (8), 1'''-O-beta-D-glucosylformoside (9), and salidroside (10). Compounds 1-9 inhibited adipocyte differentiation in 3T3-L1 cells. Dilutions of the aqueous extract of F. excelsior (1:10,000) as well as compounds 2, 3, 4, 5, and 8 activated the peroxisome proliferator-mediated receptor-alpha (PPARalpha) reporter cell system in the range of 10(-4) M, compared to 10(-7)-10(-8) M for the synthetic PPARalpha activator, WY14,643. Both biological activity profiles support the hypothesis that inhibition of adipocyte differentiation and PPARalpha-mediated mechanisms might be relevant pathways for the antidiabetic activity of F. excelsior extract.

  18. Breast Milk of HIV-Positive Mothers Has Potent and Species-Specific In Vivo HIV-Inhibitory Activity

    PubMed Central

    Wahl, Angela; Baker, Caroline; Spagnuolo, Rae Ann; Stamper, Lisa W.; Fouda, Genevieve G.; Permar, Sallie R.; Hinde, Katie; Kuhn, Louise; Bode, Lars; Aldrovandi, Grace M.

    2015-01-01

    ABSTRACT Despite the nutritional and health benefits of breast milk, breast milk can serve as a vector for mother-to-child HIV transmission. Most HIV-infected infants acquire HIV through breastfeeding. Paradoxically, most infants breastfed by HIV-positive women do not become infected. This is potentially attributed to anti-HIV factors in breast milk. Breast milk of HIV-negative women can inhibit HIV infection. However, the HIV-inhibitory activity of breast milk from HIV-positive mothers has not been evaluated. In addition, while significant differences in breast milk composition between transmitting and nontransmitting HIV-positive mothers have been correlated with transmission risk, the HIV-inhibitory activity of their breast milk has not been compared. This knowledge may significantly impact the design of prevention approaches in resource-limited settings that do not deny infants of HIV-positive women the health benefits of breast milk. Here, we utilized bone marrow/liver/thymus humanized mice to evaluate the in vivo HIV-inhibitory activity of breast milk obtained from HIV-positive transmitting and nontransmitting mothers. We also assessed the species specificity and biochemical characteristics of milk's in vivo HIV-inhibitory activity and its ability to inhibit other modes of HIV infection. Our results demonstrate that breast milk of HIV-positive mothers has potent HIV-inhibitory activity and indicate that breast milk can prevent multiple routes of infection. Most importantly, this activity is unique to human milk. Our results also suggest multiple factors in breast milk may contribute to its HIV-inhibitory activity. Collectively, our results support current recommendations that HIV-positive mothers in resource-limited settings exclusively breastfeed in combination with antiretroviral therapy. IMPORTANCE Approximately 240,000 children become infected with HIV annually, the majority via breastfeeding. Despite daily exposure to virus in breast milk, most infants

  19. Natural products possessing protein tyrosine phosphatase 1B (PTP1B) inhibitory activity found in the last decades

    PubMed Central

    Jiang, Cheng-shi; Liang, Lin-fu; Guo, Yue-wei

    2012-01-01

    This article provides an overview of approximately 300 secondary metabolites with inhibitory activity against protein tyrosine phosphatase 1B (PTP1B), which were isolated from various natural sources or derived from synthetic process in the last decades. The structure-activity relationship and the selectivity of some compounds against other protein phosphatases were also discussed. Potential pharmaceutical applications of several PTP1B inhibitors were presented. PMID:22941286

  20. Cholinesterase inhibitory activity of isoquinoline alkaloids from three Cryptocarya species (Lauraceae).

    PubMed

    Wan Othman, Wan Nurul Nazneem; Liew, Sook Yee; Khaw, Kooi Yeong; Murugaiyah, Vikneswaran; Litaudon, Marc; Awang, Khalijah

    2016-09-15

    Alzheimer's disease is the most common form of dementia among older adults. Acetylcholinesterase and butyrylcholinesterase are two enzymes involved in the breaking down of the neurotransmitter acetylcholine. Inhibitors for these enzymes have potential to prolong the availability of acetylcholine. Hence, the search for such inhibitors especially from natural products is needed in developing potential drugs for Alzheimer's disease. The present study investigates the cholinesterase inhibitory activity of compounds isolated from three Cryptocarya species towards acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Nine alkaloids were isolated; (+)-nornantenine 1, (-)-desmethylsecoantofine 2, (+)-oridine 3, (+)-laurotetanine 4 from the leaves of Cryptocarya densiflora BI., atherosperminine 5, (+)-N-methylisococlaurine 6, (+)-N-methyllaurotetanine 7 from the bark of Cryptocarya infectoria Miq., 2-methoxyatherosperminine 8 and (+)-reticuline 9 from the bark of Cryptocarya griffithiana Wight. In general, most of the alkaloids showed higher inhibition towards BChE as compared to AChE. The phenanthrene type alkaloid; 2-methoxyatherosperminine 8, exhibited the most potent inhibition against BChE with IC50 value of 3.95μM. Analysis of the Lineweaver-Burk (LB) plot of BChE activity over a range of substrate concentration suggested that 2-methoxyatherosperminine 8 exhibited mixed-mode inhibition with an inhibition constant (Ki) of 6.72μM. Molecular docking studies revealed that 2-methoxyatherosperminine 8 docked well at the choline binding site and catalytic triad of hBChE (butyrylcholinesterase from Homo sapiens); hydrogen bonding with Tyr 128 and His 438 residues respectively. PMID:27492195

  1. Memory retrieval of inhibitory avoidance requires histamine H1 receptor activation in the hippocampus.

    PubMed

    Fabbri, Roberta; Furini, Cristiane Regina Guerino; Passani, Maria Beatrice; Provensi, Gustavo; Baldi, Elisabetta; Bucherelli, Corrado; Izquierdo, Ivan; de Carvalho Myskiw, Jociane; Blandina, Patrizio

    2016-05-10

    Retrieval represents a dynamic process that may require neuromodulatory signaling. Here, we report that the integrity of the brain histaminergic system is necessary for retrieval of inhibitory avoidance (IA) memory, because rats depleted of histamine through lateral ventricle injections of α-fluoromethylhistidine (a-FMHis), a suicide inhibitor of histidine decarboxylase, displayed impaired IA memory when tested 2 d after training. a-FMHis was administered 24 h after training, when IA memory trace was already formed. Infusion of histamine in hippocampal CA1 of brain histamine-depleted rats (hence, amnesic) 10 min before the retention test restored IA memory but was ineffective when given in the basolateral amygdala (BLA) or the ventral medial prefrontal cortex (vmPFC). Intra-CA1 injections of selective H1 and H2 receptor agonists showed that histamine exerted its effect by activating the H1 receptor. Noteworthy, the H1 receptor antagonist pyrilamine disrupted IA memory retrieval in rats, thus strongly supporting an active involvement of endogenous histamine; 90 min after the retention test, c-Fos-positive neurons were significantly fewer in the CA1s of a-FMHis-treated rats that displayed amnesia compared with in the control group. We also found reduced levels of phosphorylated cAMP-responsive element binding protein (pCREB) in the CA1s of a-FMHis-treated animals compared with in controls. Increases in pCREB levels are associated with retrieval of associated memories. Targeting the histaminergic system may modify the retrieval of emotional memory; hence, histaminergic ligands might reduce dysfunctional aversive memories and improve the efficacy of exposure psychotherapies.

  2. Inhibitory effects of kiwifruit extract on human platelet aggregation and plasma angiotensin-converting enzyme activity.

    PubMed

    Dizdarevic, Lili L; Biswas, Dipankar; Uddin, M D Main; Jørgenesen, Aud; Falch, Eva; Bastani, Nasser E; Duttaroy, Asim K

    2014-01-01

    Previous human studies suggest that supplementation with kiwifruits lowers several cardiovascular risk factors such as platelet hyperactivity, blood pressure and plasma lipids. The cardiovascular health benefit of fruit and vegetables is usually attributed to the complex mixture of phytochemicals therein; however, kiwifruit's cardioprotective factors are not well studied. In this study, we investigated the effects of kiwifruit extract on human blood platelet aggregation and plasma angiotensin-converting enzyme (ACE) activity. A sugar-free, heat-stable aqueous extract with molecular mass less than 1000 Da was prepared from kiwifruits. Typically, 100 g kiwifruits produced 66.3 ± 5.8 mg (1.2 ± 0.1 mg CE) of sugar-free kiwifruit extract (KFE). KFE inhibited both human platelet aggregation and plasma ACE activity in a dose-dependent manner. KFE inhibited platelet aggregation in response to ADP, collagen and arachidonic acid, and inhibitory action was mediated in part by reducing TxA2 synthesis. The IC50 for ADP-induced platelet aggregation was 1.6 ± 0.2 mg/ml (29.0 ± 3.0 μg CE/ml), whereas IC50 for serum ACE was 0.6 ± 0.1 mg/ml (11.0 ± 1.2 μg CE/ml). Consuming 500 mg of KFE (9.0 mg CE) in 10 g margarine inhibited ex vivo platelet aggregation by 12.7%, 2 h after consumption by healthy volunteers (n = 9). All these data indicate that kiwifruit contains very potent antiplatelet and anti-ACE components. Consuming kiwifruits might be beneficial as both preventive and therapeutic regime in cardiovascular disease. PMID:24219176

  3. Inhibitory effects of kiwifruit extract on human platelet aggregation and plasma angiotensin-converting enzyme activity.

    PubMed

    Dizdarevic, Lili L; Biswas, Dipankar; Uddin, M D Main; Jørgenesen, Aud; Falch, Eva; Bastani, Nasser E; Duttaroy, Asim K

    2014-01-01

    Previous human studies suggest that supplementation with kiwifruits lowers several cardiovascular risk factors such as platelet hyperactivity, blood pressure and plasma lipids. The cardiovascular health benefit of fruit and vegetables is usually attributed to the complex mixture of phytochemicals therein; however, kiwifruit's cardioprotective factors are not well studied. In this study, we investigated the effects of kiwifruit extract on human blood platelet aggregation and plasma angiotensin-converting enzyme (ACE) activity. A sugar-free, heat-stable aqueous extract with molecular mass less than 1000 Da was prepared from kiwifruits. Typically, 100 g kiwifruits produced 66.3 ± 5.8 mg (1.2 ± 0.1 mg CE) of sugar-free kiwifruit extract (KFE). KFE inhibited both human platelet aggregation and plasma ACE activity in a dose-dependent manner. KFE inhibited platelet aggregation in response to ADP, collagen and arachidonic acid, and inhibitory action was mediated in part by reducing TxA2 synthesis. The IC50 for ADP-induced platelet aggregation was 1.6 ± 0.2 mg/ml (29.0 ± 3.0 μg CE/ml), whereas IC50 for serum ACE was 0.6 ± 0.1 mg/ml (11.0 ± 1.2 μg CE/ml). Consuming 500 mg of KFE (9.0 mg CE) in 10 g margarine inhibited ex vivo platelet aggregation by 12.7%, 2 h after consumption by healthy volunteers (n = 9). All these data indicate that kiwifruit contains very potent antiplatelet and anti-ACE components. Consuming kiwifruits might be beneficial as both preventive and therapeutic regime in cardiovascular disease.

  4. Inhibitory effect of CuSO₄ on α-glucosidase activity in ddY mice.

    PubMed

    Yoshikawa, Yutaka; Hirata, Ryoko; Yasui, Hiroyuki; Hattori, Masakazu; Sakurai, Hiromu

    2010-01-01

    We investigated the effects of divalent alkaline earth and first-row transition metal and zinc ions on α-glucosidase activity in vitro and in vivo. CuSO₄ and ZnSO₄ exhibited a high α-glucosidase inhibitory effect in vitro. The IC(50) values of CuSO₄ were 0.77 ± 0.01 (substrate; maltose) and 0.78 ± 0.01 (substrate; sucrose), and those of ZnSO₄ were 5.49 ± 0.14 (substrate; maltose) and 4.70 ± 0.06 (substrate; sucrose) for yeast α-glucosidase. On the basis of Lineweaver-Burk plots, both CuSO₄ and ZnSO₄ exhibited different modes of inhibition against α-glucosidase. Subsequently, oral glucose and sucrose tolerance tests (OGTT and OSTT) were performed on non-diabetic ddY mice to examine the effect of the metal ions on their blood glucose levels. As a result of single oral administration of CuSO₄ in non-diabetic ddY mice, a significant and potent lowering of the blood glycemic response toward disaccharide, sucrose, ingestion was observed at 45 min after doses of 0.08 and 0.24 mmol kg(-1) body weight. In contrast, the CuSO₄ administration showed no suppression of the elevation of blood glucose levels in mice after a monosaccharide, glucose, administration. These results indicate that CuSO₄ suppresses disaccharide digestion by inhibiting α-glucosidase activity in the epithelium of the small intestine, suggesting that antidiabetic Cu complexes with some ligands have a similar action mechanism to that of α-glucosidase inhibitor, acarbose, currently used for clinical purposes. PMID:21072376

  5. Fermentation with Aspergillus awamori enhanced contents of amino nitrogen and total phenolics as well as the low-density lipoprotein oxidation inhibitory activity of black soybeans.

    PubMed

    Chen, Yu-Fei; Lee, Shiow-Ling; Chou, Cheng-Chun

    2011-04-27

    A solid fermentation was performed on black soybeans with Aspergillus awamori. The effects of fermentation on the contents of total phenolics and amino nitrogen and on the inhibitory effect on low-density lipoprotein (LDL) oxidation of black soybeans were examined. Results revealed that fermentation significantly enhanced the LDL oxidation inhibitory activity and total phenolics and amino nitrogen contents of black soybeans. The increased content of amino nitrogen was closely related to the enhanced LDL oxidation inhibitory activity of fermented black soybeans and its water extract. Fermentation temperature and length affected the LDL oxidation inhibitory effect exerted by the prepared fermented black soybeans. The A. awamori-fermented black soybean prepared at 30 °C for 3 days exhibited the highest inhibitory effect on LDL oxidation. The bioactive principles related to the inhibitory effect on LDL oxidation in black soybeans, regardless of fermentation, could be most efficiently extracted with water rather than 80% methanol or 80% ethanol.

  6. Relationship between structure and P-glycoprotein inhibitory activity of dimeric peptides related to the Dmt-Tic pharmacophore.

    PubMed

    Ambo, Akihiro; Ohkatsu, Hiromichi; Minamizawa, Motoko; Watanabe, Hideko; Sugawara, Shigeki; Nitta, Kazuo; Tsuda, Yuko; Okada, Yoshio; Sasaki, Yusuke

    2012-03-15

    To develop novel inhibitors of P-glycoprotein (P-gp), dimeric peptides related to an opioid peptide containing the Dmt-Tic pharmacophore were synthesized and their P-gp inhibitory activities were analyzed. Of the 30 analogs synthesized, N(α),N(ε)-[(CH(3))(2)Mle-Tic](2)Lys-NH(2) and its D-Lys analog were found to exhibit potent P-gp inhibitory activity, twice that of verapamil, in doxorubicin-resistant K562 cells. Structure-activity studies indicated that the correct hydrophobicity and spacer length between two aromatic rings are important structural elements in this series of analogs for inhibition of P-gp.

  7. An expedient synthesis, acetylcholinesterase inhibitory activity, and molecular modeling study of highly functionalized hexahydro-1,6-naphthyridines.

    PubMed

    Almansour, Abdulrahman I; Kumar, Raju Suresh; Arumugam, Natarajan; Basiri, Alireza; Kia, Yalda; Ali, Mohamed Ashraf

    2015-01-01

    A series of hexahydro-1,6-naphthyridines were synthesized in good yields by the reaction of 3,5-bis[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones with cyanoacetamide in the presence of sodium ethoxide under simple mixing at ambient temperature for 6-10 minutes and were assayed for their acetylcholinesterase (AChE) inhibitory activity using colorimetric Ellman's method. Compound 4e with methoxy substituent at ortho-position of the phenyl rings displayed the maximum inhibitory activity with IC50 value of 2.12 μM. Molecular modeling simulation of 4e was performed using three-dimensional structure of Torpedo californica AChE (TcAChE) enzyme to disclose binding interaction and orientation of this molecule into the active site gorge of the receptor. PMID:25710037

  8. Isolation, modification, and aldose reductase inhibitory activity of rosmarinic acid derivatives from the roots of Salvia grandifolia.

    PubMed

    Kang, Jie; Tang, Yanbo; Liu, Quan; Guo, Nan; Zhang, Jian; Xiao, Zhiyan; Chen, Ruoyun; Shen, Zhufang

    2016-07-01

    To find aldose reductase inhibitors, two previously unreported compounds, grandifolias H and I, and five known compounds, including rosmarinic acid and rosmarinic acid derivatives, were isolated from the roots of Salvia grandifolia. A series of rosmarinic acid derivatives was obtained from rosmarinic acid using simple synthetic methods. The aldose reductase inhibitory activity of the isolated and synthesized compounds was assessed. Seven of the tested compounds showed moderate aldose reductase inhibition (IC50=0.06-0.30μM). The structure-activity relationship of aldose reductase inhibitory activity of rosmarinic acid derivatives was discussed for the first time. This study provided useful information that will facilitate the development of aldose reductase inhibitors. PMID:27233987

  9. An Expedient Synthesis, Acetylcholinesterase Inhibitory Activity, and Molecular Modeling Study of Highly Functionalized Hexahydro-1,6-naphthyridines

    PubMed Central

    Almansour, Abdulrahman I.; Suresh Kumar, Raju; Arumugam, Natarajan; Basiri, Alireza; Kia, Yalda; Ashraf Ali, Mohamed

    2015-01-01

    A series of hexahydro-1,6-naphthyridines were synthesized in good yields by the reaction of 3,5-bis[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones with cyanoacetamide in the presence of sodium ethoxide under simple mixing at ambient temperature for 6–10 minutes and were assayed for their acetylcholinesterase (AChE) inhibitory activity using colorimetric Ellman's method. Compound 4e with methoxy substituent at ortho-position of the phenyl rings displayed the maximum inhibitory activity with IC50 value of 2.12 μM. Molecular modeling simulation of 4e was performed using three-dimensional structure of Torpedo californica AChE (TcAChE) enzyme to disclose binding interaction and orientation of this molecule into the active site gorge of the receptor. PMID:25710037

  10. Angular-type furocoumarins from the roots of Angelica atropurpurea and their inhibitory activity on the NFAT signal transduction pathway.

    PubMed

    Nagasawa, Azumi; Sakasai, Mitsuyoshi; Sakaguchi, Daishi; Moriwaki, Shigeru; Nishizawa, Yoshinori; Kitahara, Takashi

    2014-12-01

    One new (1) and two known angular-type (2,3) furocoumarins, isoarchangelicin (1), archangelicin (2), and 2'-angeloyl-3'-isovaleryl vaginate (3), were isolated from the roots of Angelica atropurpurea. The structure of the new compound was established on the basis of one- and two-dimensional NMR spectra and other spectroscopic studies. The inhibitory activity of these three compounds and a deacylated form of archangelicin (4) on the nuclear factor of activated T cells (NFAT) signal transduction pathway was tested by NFAT-responsive luciferase reporter gene assay in cultured cells. Although 4 did not exhibit inhibitory activity on NFAT signaling, 1-3 exhibited dose-dependent inhibition with IC50 values of 16.5 (1), 9.0 (2), and 9.2 (3) μM.

  11. Differential inhibitory effects of methylmalonic acid on respiratory chain complex activities in rat tissues.

    PubMed

    Pettenuzzo, Leticia F; Ferreira, Gustavo da C; Schmidt, Anna Laura; Dutra-Filho, Carlos S; Wyse, Angela T S; Wajner, Moacir

    2006-02-01

    Methylmalonic acidemia is an inherited metabolic disorder biochemically characterized by tissue accumulation of methylmalonic acid (MMA) and clinically by progressive neurological deterioration and kidney failure, whose pathophysiology is so far poorly established. Previous studies have shown that MMA inhibits complex II of the respiratory chain in rat cerebral cortex, although no inhibition of complexes I-V was found in bovine heart. Therefore, in the present study we investigated the in vitro effect of 2.5mM MMA on the activity of complexes I-III, II, II-III and IV in striatum, hippocampus, heart, liver and kidney homogenates from young rats. We observed that MMA caused a significant inhibition of complex II activity in striatum and hippocampus (15-20%) at low concentrations of succinate in the medium, but not in the peripheral tissues. We also verified that the inhibitory property of MMA only occurred after exposing brain homogenates for at least 10 min with the acid, suggesting that this inhibition was mediated by indirect mechanisms. Simultaneous preincubation with the nitric oxide synthase inhibitor Nomega-nitro-L-arginine methyl ester (L-NAME) and catalase (CAT) plus superoxide dismutase (SOD) did not prevent MMA-induced inhibition of complex II, suggesting that common reactive oxygen (superoxide, hydrogen peroxide and hydroxyl radical) and nitric (nitric oxide) species were not involved in this effect. In addition, complex II-III (20-35%) was also inhibited by MMA in all tissues tested, and complex I-III only in the kidney (53%) and liver (38%). In contrast, complex IV activity was not changed by MMA in all tissues studied. These results indicate that MMA differentially affects the activity of the respiratory chain pending on the tissues studied, being striatum and hippocampus more vulnerable to its effect. In case our in vitro data are confirmed in vivo in tissues from methylmalonic acidemic patients, it is feasible that that the present findings may be

  12. Limonoids from Azadirachta indica var. siamensis extracts and their cytotoxic and melanogenesis-inhibitory activities.

    PubMed

    Manosroi, Aranya; Kitdamrongtham, Worapong; Ishii, Kenta; Shinozaki, Takuro; Tachi, Yosuke; Takagi, Mio; Ebina, Kodai; Zhang, Jie; Manosroi, Jiradej; Akihisa, Rima; Akihisa, Toshihiro

    2014-04-01

    Six new limonoids, 7-benzoyl-17-epinimbocinol (5), 3-acetyl-7-tigloylnimbidinin (8), 1-isovaleroyl-1-detigloylsalanninolide (15), 2,3-dihydro-3α-methoxynimbolide (16), deacetyl-20,21-epoxy-20,22-dihydro-21-deoxyisonimbinolide (26), and deacetyl-20,21,22,23-tetrahydro-20,22-dihydroxy-21,23-dimethoxynimbin (27), along with 28 known limonoids, 1-4, 6, 7, 9-14, 17-25, and 28-34, and two known flavonoids, 35 and 36, have been isolated from the extracts of bark, leaves, roots, and seeds of Azadirachta indica A. Juss. var. siamensis Valeton (Siamese neem tree; Meliaceae). The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. All of these compounds were evaluated for their cytotoxic activities against leukemia (HL60), lung (A549), stomach (AZ521), and breast (SK-BR-3) cancer cell lines. Eleven compounds, 1, 2, 4-7, 13, 16, 17, 29, and 30, exhibited potent cytotoxicities against one or more cell lines with IC50 values in the range of 0.1-9.3 μM. Compound 16 induced apoptotic cell death in AZ521 cells upon evaluation of the apoptosis-inducing activity by flow cytometric analysis. Western blot analysis on AZ521 cells revealed that compound 16 activated caspases-3, -8, and -9, while increasing the ratio of Bax/Bcl-2. This suggested that 16 induced apoptosis via both mitochondrial and death receptor pathways in AZ521. In addition, upon evaluation of all compounds against the melanogenesis in B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH), 20 limonoids, i.e., 1-3, 6, 9-11, 18, 19, 21-29, 32, and 34, and two flavonoids, 35 and 36, exhibited melanogenesis-inhibitory activities, with no, or almost no, toxicities to the cells at lower and/or higher concentrations, which were more potent than the reference arbutin, a known melanogenesis inhibitor. Western blot analysis showed that nimbin (18) reduced the protein levels of microphtalmia-associated transcription factor

  13. Antioxidant and ACE Inhibitory Activity of Cultivated and Wild Angelica gigas Nakai Extracts Prepared Using Different Extraction Conditions

    PubMed Central

    Noh, Bo-Young; Lee, Hye-Jin; Do, Jeong-Ryong; Kim, Hyun-Ku

    2014-01-01

    The purpose of this study was to investigate the biological activities of cultivated Angelica gigas Nakai (CAG) and wild Angelica gigas Nakai (WAG) extracts prepared by extraction with water, 30% ethanol, 60% ethanol, or 90% ethanol. The electron donating ability of the WAG extracts was higher than that of the CAG extracts and 0.1% and 1.0% solutions of the comparative substance, L-ascorbic acid. The superoxide dismutase-like activity of the CAG extracts was higher than that of WAG extracts. Superoxide dismutase-like activity was highest (33.95%) in the CAG water extract. The total polyphenol content was highest in the 60% ethanol extracts of WAG. The nitrite scavenging ability of the CAG and WAG extracts was highest at a pH of 1.2. The tyrosinase inhibitory effect was highest (43.72%) in the water extract of WAG. The angiotensin converting enzyme inhibitory activity was highest (83.84%) in the 60% ethanol extract of WAG. The results of the present study will be useful for understanding the antioxidant and angiotensin-converting enzyme inhibitory activities of Angelica gigas Nakai extracts. PMID:25580391

  14. Physical and biological characterization of a growth-inhibitory activity purified from the neuroepithelioma cell line A673.

    PubMed Central

    Stam, K; Stewart, A A; Qu, G Y; Iwata, K K; Fenyö, D; Chait, B T; Marshak, D R; Haley, J D

    1995-01-01

    Epithelial- and haematopoietic-cell growth-inhibitory activities have been identified in the conditioned medium of the human peripheral neuroepithelioma cell line A673. An A673-cell-derived growth-inhibitory activity was previously fractionated into two distinct components which inhibited the proliferation of human carcinoma and leukaemia cells in culture. One inhibitory activity was shown to comprise interleukin-1 alpha (IL-1 alpha). Here, we have purified to homogeneity a distinct activity which inhibited the growth of the epithelial cells in vitro. Using a combination of protein-sequence analysis and mass spectrometry, we demonstrated that biological activity can be assigned to a dimeric protein with a molecular mass of 25,576 (+/- 4) Da and an N-terminal sequence identical with that of transforming growth factor-beta 1 (TGF-beta 1). Further characterization of the growth inhibitor with TGF-beta-isoform-specific antibodies showed that > 90% of the bioactivity consists of TGF-beta 1 and not TGF-beta 2 or TGF-beta 3. Although A673 cells were growth-inhibited by exogenous TGF-beta 1, we showed that TGF-beta 1 in A673-cell-conditioned media was present in the latent, biologically inactive, form which did not act as an autocrine growth modulator of A673 cells in vitro. Images Figure 2 Figure 3 PMID:7826358

  15. QSAR study for the soybean 15-lipoxygenase inhibitory activity of organosulfur compounds derived from the essential oil of garlic.

    PubMed

    Camargo, Alejandra B; Marchevsky, Eduardo; Luco, Juan M

    2007-04-18

    In this study, multiple linear regression (MLR) and partial least-squares (PLS) techniques were used for modeling the soybean 15-lipoxygenase inhibitory activity of a varied group of mono-, di-, and trisulfides derived from the essential oil of garlic. The structures of the compounds under study were characterized by means of calculated physicochemical parameters and several nonempirical descriptors, such as topological, geometrical, and quantum chemical indices. The results obtained indicate that the inhibitory activity is strongly dependent on the ability of the compounds to participate in dispersive interactions with the enzyme, as expressed by the solvent-accessible surface area (SASA) and the average distance/distance degree descriptor (ADDD) index. On the other hand, the high contribution of the lowest unoccupied molecular orbit term (LUMO) in the PLS models derived for the di- and trisulfides suggests that the solute's electron-acceptor capacity plays a fundamental role in the inhibitory activity exhibited for these compounds. Finally, the geometric features as expressed by the shape parameters included in the models indicate a low but not negligible positive contribution of molecular linearity in the enzyme-inhibitor binding. In summary, the developed quantitative structure-activity relationship approach successfully accounts for the potencies of organosulfur compounds acting on soybean 15-lipoxygenase and thereby offers both a guide for the synthesis of new compounds and a hypothesis for the molecular basis of their activity. PMID:17367159

  16. Biological activity of a genetically modified BMP-2 variant with inhibitory activity

    PubMed Central

    Klammert, Uwe; Nickel, Joachim; Würzler, Kristian; Klingelhöffer, Christoph; Sebald, Walter; Kübler, Alexander C; Reuther, Tobias

    2009-01-01

    Background Alterations of the binding epitopes of bone morphogenetic protein-2 (BMP-2) lead to a modified interaction with the ectodomains of BMP receptors. In the present study the biological effect of a BMP-2 double mutant with antagonistic activity was evaluated in vivo. Methods Equine-derived collagenous carriers were loaded with recombinant human BMP-2 (rhBMP-2) in a well-known dose to provide an osteoinductive stimulus. The study was performed in a split animal design: carriers only coupled with rhBMP-2 (control) were implanted into prepared cavities of lower limb muscle of rats, specimens coupled with rhBMP-2 as well as BMP-2 double mutant were placed into the opposite limb in the same way. After 28 days the carriers were explanted, measured radiographically and characterized histologically. Results As expected, the BMP-2 loaded implants showed a typical heterotopic bone formation. The specimens coupled with both proteins showed a significant decreased bone formation in a dose dependent manner. Conclusion The antagonistic effect of a specific BMP-2 double mutant could be demonstrated in vivo. The dose dependent influence on heterotopic bone formation by preventing rhBMP-2 induced osteoinduction suggests a competitive receptor antagonism. PMID:19187528

  17. Anthocyanin content, lipid peroxidation and cyclooxygenase enzyme inhibitory activities of sweet and sour cherries.

    PubMed

    Mulabagal, Vanisree; Lang, Gregory A; DeWitt, David L; Dalavoy, Sanjeev S; Nair, Muraleedharan G

    2009-02-25

    Cherries contain bioactive anthocyanins that are reported to possess antioxidant, anti-inflammatory, anticancer, antidiabetic and antiobese properties. The present study revealed that red sweet cherries contained cyanidin-3-O-rutinoside as major anthocyanin (>95%). The sweet cherry cultivar "Kordia" (aka "Attika") showed the highest cyanidin-3-O-rutinoside content, 185 mg/100 g fresh weight. The red sweet cherries "Regina" and "Skeena" were similar to "Kordia", yielding cyanidin-3-O-rutinoside at 159 and 134 mg/100 g fresh weight, respectively. The yields of cyanidin-3-O-glucosylrutinoside and cyanidin-3-O-rutinoside were 57 and 19 mg/100 g fresh weight in "Balaton" and 21 and 6.2 mg/100 g fresh weight in "Montmorency", respectively, in addition to minor quantities of cyanidin-3-O-glucoside. The water extracts of "Kordia", "Regina", "Glacier" and "Skeena" sweet cherries gave 89, 80, 80 and 70% of lipid peroxidation (LPO) inhibition, whereas extracts of "Balaton" and "Montmorency" were in the range of 38 to 58% at 250 microg/mL. Methanol and ethyl acetate extracts of the yellow sweet cherry "Rainier" containing beta-carotene, ursolic, coumaric, ferulic and cafeic acids inhibited LPO by 78 and 79%, respectively, at 250 microg/mL. In the cyclooxygenase (COX) enzyme inhibitory assay, the red sweet cherry water extracts inhibited the enzymes by 80 to 95% at 250 microg/mL. However, the methanol and ethyl acetate extracts of "Rainier" and "Gold" were the most active against COX-1 and -2 enzymes. Water extracts of "Balaton" and "Montmorency" inhibited COX-1 and -2 enzymes by 84, and 91 and 77, and 87%, respectively, at 250 microg/mL. PMID:19199585

  18. Biotransformation of dianabol with the filamentous fungi and β-glucuronidase inhibitory activity of resulting metabolites.

    PubMed

    Khan, Naik T; Zafar, Salman; Noreen, Shagufta; Al Majid, Abdullah M; Al Othman, Zeid A; Al-Resayes, Saud Ibrahim; Atta-ur-Rahman; Choudhary, M Iqbal

    2014-07-01

    Biotransformation of the anabolic steroid dianabol (1) by suspended-cell cultures of the filamentous fungi Cunninghamella elegans and Macrophomina phaseolina was studied. Incubation of 1 with C. elegans yielded five hydroxylated metabolites 2-6, while M. phaseolina transformed compound 1 into polar metabolites 7-11. These metabolites were identified as 6β,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (2), 15α,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (3), 11α,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (4), 6β,12β,17β-trihydroxy-17α-methylandrost-1,4-dien-3-one (5), 6β,15α,17β-trihydroxy-17α-methylandrost-1,4-dien-3-one (6), 17β-hydroxy-17α-methylandrost-1,4-dien-3,6-dione (7), 7β,17β,-dihydroxy-17α-methylandrost-1,4-dien-3-one (8), 15β,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (9), 17β-hydroxy-17α-methylandrost-1,4-dien-3,11-dione (10), and 11β,17β-dihydroxy-17α-methylandrost-1,4-dien-3-one (11). Metabolite 3 was also transformed chemically into diketone 12 and oximes 13, and 14. Compounds 6 and 12-14 were identified as new derivatives of dianabol (1). The structures of all transformed products were deduced on the basis of spectral analyses. Compounds 1-14 were evaluated for β-glucuronidase enzyme inhibitory activity. Compounds 7, 13, and 14 showed a strong inhibition of β-glucuronidase enzyme, with IC50 values between 49.0 and 84.9 μM. PMID:24755238

  19. Shrimp single WAP domain (SWD)-containing protein exhibits proteinase inhibitory and antimicrobial activities.

    PubMed

    Amparyup, Piti; Donpudsa, Suchao; Tassanakajon, Anchalee

    2008-01-01

    Single WAP domain (SWD)-containing proteins are small proteins with a C-terminal region containing a single whey acidic protein (WAP) domain. In the present study, the cDNAs representing three isoforms of SWD proteins (SWDPm1, SWDPm2 and SWDPm3) were identified from hemocytes of the black tiger shrimp, Penaeus monodon. The deduced peptides revealed that they contain a putative signal peptide of 24 amino acids and encode for a mature peptide of 69, 68 and 56 amino acids, respectively, which contain typical characters similar to those of the shrimp SWD proteins (type III crustin) with a Pro-Arg region and a WAP domain towards the C-terminus. Tissue distribution analysis by RT-PCR showed that all three SWDPm transcripts were primarily found in hemocytes. Transcript expression of SWDPm1 was down-regulated upon injection with Staphylococcus aureus whilst there was no change of SWDPm2 and SWDPm3 expression. In contrast, white spot syndrome virus (WSSV) injection resulted in a biphasic response with up-regulation of SWDPm1 and SWDPm2 transcripts at 6h followed by significant down-regulation by 24h after infection. Genomic organization of the SWDPm2 gene revealed the presence of three exons interrupted by two introns. To characterize the biological functions of the SWD protein, the mature SWDPm2 protein encoding cDNA was cloned and expressed in Escherichia coli. Purified recombinant (r)SWDPm2 exhibits antibacterial activity against several Gram-positive, but not Gram-negative, bacteria and is a competitive inhibitor of subtilisin A with an inhibition constant (Ki) of 1.98nM. Thus, rSWDPm2 may contribute to the inhibitory regulation of subtilisin A from bacterial infection and P. monodon SWD protein likely function as immune effectors in defense against invasion of shrimp pathogens. PMID:18602420

  20. The X protein of hepatitis B virus activates hepatoma cell proliferation through repressing melanoma inhibitory activity 2 gene

    SciTech Connect

    Xu, Yilin; Yang, Yang; Cai, Yanyan; Liu, Fang; Liu, Yingle; Zhu, Ying; Wu, Jianguo

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer We demonstrated that HBV represses MIA2 gene expression both invitro and in vivo. Black-Right-Pointing-Pointer The X protein of HBV plays a major role in such regulation. Black-Right-Pointing-Pointer Knock-down of MIA2 in HepG2 cells activates cell growth and proliferation. Black-Right-Pointing-Pointer HBx activates cell proliferation, over-expression of MIA2 impaired such regulation. Black-Right-Pointing-Pointer HBx activates hepatoma cell proliferation through repressing MIA2 expression. -- Abstract: Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer deaths globally. Chronic hepatitis B virus (HBV) infection accounts for over 75% of all HCC cases; however, the molecular pathogenesis of HCC is not well understood. In this study, we found that the expression of the newly identified gene melanoma inhibitory activity 2 (MIA2) was reduced by HBV infection invitro and invivo, and that HBV X protein (HBx) plays a major role in this regulation. Recent studies have revealed that MIA2 is a potential tumor suppressor, and that, in most HCCs, MIA2 expression is down-regulated or lost. We found that the knock-down of MIA2 in HepG2 cells activated cell growth and proliferation, suggesting that MIA2 inhibits HCC cell growth and proliferation. In addition, the over-expression of HBx alone induced cell proliferation, whereas MIA2 over-expression impaired the HBx-mediated induction of proliferation. Taken together, our results suggest that HBx activates hepatoma cell growth and proliferation through repression of the potential tumor suppressor MIA2.

  1. Inhibitory effects of SKF96365 on the activities of K+ channels in mouse small intestinal smooth muscle cells

    PubMed Central

    TANAHASHI, Yasuyuki; WANG, Ban; MURAKAMI, Yuri; UNNO, Toshihiro; MATSUYAMA, Hayato; NAGANO, Hiroshi; KOMORI, Seiichi

    2015-01-01

    In order to investigate the effects of SKF96365 (SKF), which is a non-selective cationic channel blocker, on K+ channel currents, we recorded currents through ATP sensitive K+ (IKATP), voltage-gated K+ (IKv) and Ca2+ activated K+ channels (IBK) in the absence and presence of SKF in single small intestinal myocytes of mice with patch-clamp techniques. SKF (10 µM) reversibly abolished IKATP that was induced by cromakalim (10 µM), which is a selective ATP sensitive K+ channel opener. These inhibitory effects were induced in a concentration-dependent and voltage-independent manner. The 50% inhibitory concentration (IC50) was 0.85 µM, which was obviously lower than that reported for the muscarinic cationic current. In addition, SKF (1 µM ≈ the IC50 value in IKATP suppression) reversibly inhibited the IKv that was induced by repetitive depolarizing pulses from −80 to 20 mV. However, the extent of the inhibitory effects was only ~30%. In contrast, SKF (1 µM) had no significant effects on spontaneous transient IBK and caffeine-induced IBK. These results indicated that SKF inhibited ATP sensitive K+ channels and voltage-gated K+ channels, with the ATP sensitive K+ channels being more sensitive than the voltage-gated K+ channels. These inhibitory effects on K+ channels should be considered when SKF is used as a cationic channel blocker. PMID:26498720

  2. Inhibitory effects of flavonoids on phosphodiesterase isozymes from guinea pig and their structure-activity relationships.

    PubMed

    Ko, Wun-Chang; Shih, Chwen-Ming; Lai, Ya-Hsin; Chen, Jun-Hao; Huang, Hui-Lin

    2004-11-15

    The structure-activity relationships of flavonoids with regard to their inhibitory effects on phosphodiesterase (PDE) isozymes are little known. The activities of PDE1-5 were measured by a two-step procedure using cAMP with [(3)H]-cAMP or cGMP with [(3)H]-cGMP as substrates. In the present results, PDE1, 5, 2, and 4 isozymes were partially purified from guinea pig lungs in that order, and PDE3 was from the heart. The IC(50) values of PDE1-5 were greater than those reported previously for the reference drugs, vinpocetin, EHNA, milrinone, Ro 20-1724, and zaprinast, by 5-, 5-, 7-, 5-, and 3-fold, respectively. As shown in Table 2, luteolin revealed non-selective inhibition of PDE1-5 with IC(50) values in a range of 10-20 microM, as did genistein except with a low potency on PDE5. Daidzein, an inactive analogue of genistein in tyrosine kinase inhibition, showed selective inhibition of PDE3 with an IC(50) value of around 30 microM, as did eriodictyol with an IC(50) value of around 50 microM. Hesperetin and prunetin exhibited more-selective inhibition of PDE4 with IC(50) values of around 30 and 60 microM, respectively. Luteolin-7-glucoside exhibited dual inhibition of PDE2/PDE4 with an IC(50) value of around 40 microM. Diosmetin more-selectively inhibited PDE2 (IC(50) of 4.8 microM) than PDE1, PDE4, or PDE5. However, biochanin A more-selectively inhibited PDE4 (IC(50) of 8.5 microM) than PDE1 or PDE2. Apigenin inhibited PDE1-3 with IC(50) values of around 10-25 microM. Myricetin inhibited PDE1-4 with IC(50) values of around 10-40 microM. The same was true for quercetin, but we rather consider that it more-selectively inhibited PDE3 and PDE4 (IC(50) of < 10 microM). In conclusion, it is possible to synthesize useful drugs through elucidating the structure-activity relationships of flavonoids with respect to inhibition of PDE isozymes at concentrations used in this in vitro study.

  3. Nicotine enhances both excitatory and inhibitory synaptic inputs to inspiratory-activated airway vagal preganglionic neurons.

    PubMed

    Zhou, Xujiao; Chen, Yonghua; Ge, Dengyun; Yuan, Wenjun; Wang, Jijiang

    2013-01-01

    The airway vagal preganglionic neurons (AVPNs) supply the essential excitatory drive to the postganglionic neurons and dominate the neural control of the airway both physiologically and pathophysiologically. The AVPNs express multiple subunits of nicotinic acetylcholine receptors (nAChRs), but the influences of exogenous nicotine and endogenous acetylcholine are unknown. This study examined the effects of nicotine and endogenous acetylcholine on retrogradely labelled, functionally identified inspiratory-activated AVPNs (IA-AVPNs) using the patch-clamp technique. Nicotine (10 μmol l(-1)) significantly increased the frequency and amplitude of the spontaneous EPSCs of IA-AVPNs, and these effects were insensitive to methyllycaconitine (MLA, 100 nmol l(-1)), an antagonist of the α7 type of nAChR, but was prevented by dihydro-β-erythroidine (DHβE, 3 μmol l(-1)), an antagonist of the α4β2 type of nAChR. Nicotine caused a tonic inward current in IA-AVPNs, which was reduced by MLA or DHβE alone, but was not abolished by co-application of MLA and DHβE. Nicotine caused a significant increase in the frequency of GABAergic and glycinergic spontaneous IPSCs and significantly increased the amplitude of glycinergic spontaneous IPSCs, all of which were prevented by DHβE. Nicotine had no effects on the miniature EPSCs or miniature IPSCs following pretreatment with TTX. Under current clamp, nicotine caused depolarization and increased the firing rate of IA-AVPNs during inspiratory intervals. Neostigmine (10 μmol l(-1)), an acetylcholinesterase inhibitor, mimicked the effects of nicotine. These results demonstrate that nicotine and endogenous ACh enhance the excitatory and inhibitory synaptic inputs of IA-AVPNs and cause a postsynaptic excitatory current and that the nicotinic effects are mediated presynaptically by activation of the α4β2 type of nAChR and postsynaptically by activation of multiple nAChRs, including α7 and α4β2 types.

  4. Inhibitory effects of flavonoids on phosphodiesterase isozymes from guinea pig and their structure-activity relationships.

    PubMed

    Ko, Wun-Chang; Shih, Chwen-Ming; Lai, Ya-Hsin; Chen, Jun-Hao; Huang, Hui-Lin

    2004-11-15

    The structure-activity relationships of flavonoids with regard to their inhibitory effects on phosphodiesterase (PDE) isozymes are little known. The activities of PDE1-5 were measured by a two-step procedure using cAMP with [(3)H]-cAMP or cGMP with [(3)H]-cGMP as substrates. In the present results, PDE1, 5, 2, and 4 isozymes were partially purified from guinea pig lungs in that order, and PDE3 was from the heart. The IC(50) values of PDE1-5 were greater than those reported previously for the reference drugs, vinpocetin, EHNA, milrinone, Ro 20-1724, and zaprinast, by 5-, 5-, 7-, 5-, and 3-fold, respectively. As shown in Table 2, luteolin revealed non-selective inhibition of PDE1-5 with IC(50) values in a range of 10-20 microM, as did genistein except with a low potency on PDE5. Daidzein, an inactive analogue of genistein in tyrosine kinase inhibition, showed selective inhibition of PDE3 with an IC(50) value of around 30 microM, as did eriodictyol with an IC(50) value of around 50 microM. Hesperetin and prunetin exhibited more-selective inhibition of PDE4 with IC(50) values of around 30 and 60 microM, respectively. Luteolin-7-glucoside exhibited dual inhibition of PDE2/PDE4 with an IC(50) value of around 40 microM. Diosmetin more-selectively inhibited PDE2 (IC(50) of 4.8 microM) than PDE1, PDE4, or PDE5. However, biochanin A more-selectively inhibited PDE4 (IC(50) of 8.5 microM) than PDE1 or PDE2. Apigenin inhibited PDE1-3 with IC(50) values of around 10-25 microM. Myricetin inhibited PDE1-4 with IC(50) values of around 10-40 microM. The same was true for quercetin, but we rather consider that it more-selectively inhibited PDE3 and PDE4 (IC(50) of < 10 microM). In conclusion, it is possible to synthesize useful drugs through elucidating the structure-activity relationships of flavonoids with respect to inhibition of PDE isozymes at concentrations used in this in vitro study. PMID:15476679

  5. Engineered staphylococcal protein A's IgG-binding domain with cathepsin L inhibitory activity

    SciTech Connect

    Bratkovic, Tomaz . E-mail: tomaz.bratkovic@ffa.uni-lj.si; Berlec, Ales; Popovic, Tatjana; Lunder, Mojca; Kreft, Samo; Urleb, Uros; Strukelj, Borut

    2006-10-13

    Inhibitory peptide of papain-like cysteine proteases, affinity selected from a random disulfide constrained phage-displayed peptide library, was grafted to staphylococcal protein A's B domain. Scaffold protein was additionally modified in order to allow solvent exposed display of peptide loop. Correct folding of fusion proteins was confirmed by CD-spectroscopy and by the ability to bind the Fc-region of rabbit IgG, a characteristic of parent domain. The recombinant constructs inhibited cathepsin L with inhibitory constants in the low-micromolar range.

  6. Melanin biosynthesis inhibitory activity of a compound isolated from young green barley (Hordeum vulgare L.) in B16 melanoma cells.

    PubMed

    Meng, Tian Xiao; Irino, Nobuto; Kondo, Ryuichiro

    2015-07-01

    In the course to find compounds that inhibit melanin biosynthesis (i.e., whitening agents), we evaluated the effects of the methanol-soluble fraction (i.e., the water-soluble portion of methanol extracts-CHP20P-MeOH eluted fraction) from young green barley leaves on melanin production in B16 melanoma cells. Activity-guided fractionation led to an isolate called tricin (compound 1) as an inhibitory compound of melanin production in B16 melanoma cells. Furthermore, tricin analogs such as tricetin, tricetin trimethyl ether, luteolin, and apigenin were used for analyzing the structure-activity relationships (SAR) of 5,7-dihydroxyflavones studies. Tricin demonstrated stronger inhibitory activity compared to three other compounds. The results suggest that a hydroxyl group at the C-4' position and methoxy groups at the C-3',5' positions of the tricin skeleton may have important roles in this inhibitory activity in B16 melanoma cells. Our results suggest that tricin inhibits melanin biosynthesis with higher efficacy than arbutin, and it could be used as a whitening agent. PMID:25827948

  7. Superresolution microscopy reveals nanometer-scale reorganization of inhibitory natural killer cell receptors upon activation of NKG2D.

    PubMed

    Pageon, Sophie V; Cordoba, Shaun-Paul; Owen, Dylan M; Rothery, Stephen M; Oszmiana, Anna; Davis, Daniel M

    2013-07-23

    Natural killer (NK) cell responses are regulated by a dynamic equilibrium between activating and inhibitory receptor signals at the immune synapse (or interface) with target cells. Although the organization of receptors at the immune synapse is important for appropriate integration of these signals, there is little understanding of this in detail, because research has been hampered by the limited resolution of light microscopy. Through the use of superresolution single-molecule fluorescence microscopy to reveal the organization of the NK cell surface at the single-protein level, we report that the inhibitory receptor KIR2DL1 is organized in nanometer-scale clusters at the surface of human resting NK cells. Nanoclusters of KIR2DL1 became smaller and denser upon engagement of the activating receptor NKG2D, establishing an unexpected crosstalk between activating receptor signals and the positioning of inhibitory receptors. These rearrangements in the nanoscale organization of surface NK cell receptors were dependent on the actin cytoskeleton. Together, these data establish that NK cell activation involves a nanometer-scale reorganization of surface receptors, which in turn affects models for signal integration and thresholds that control NK cell effector functions and NK cell development. PMID:23882121

  8. Melanin biosynthesis inhibitory activity of a compound isolated from young green barley (Hordeum vulgare L.) in B16 melanoma cells.

    PubMed

    Meng, Tian Xiao; Irino, Nobuto; Kondo, Ryuichiro

    2015-07-01

    In the course to find compounds that inhibit melanin biosynthesis (i.e., whitening agents), we evaluated the effects of the methanol-soluble fraction (i.e., the water-soluble portion of methanol extracts-CHP20P-MeOH eluted fraction) from young green barley leaves on melanin production in B16 melanoma cells. Activity-guided fractionation led to an isolate called tricin (compound 1) as an inhibitory compound of melanin production in B16 melanoma cells. Furthermore, tricin analogs such as tricetin, tricetin trimethyl ether, luteolin, and apigenin were used for analyzing the structure-activity relationships (SAR) of 5,7-dihydroxyflavones studies. Tricin demonstrated stronger inhibitory activity compared to three other compounds. The results suggest that a hydroxyl group at the C-4' position and methoxy groups at the C-3',5' positions of the tricin skeleton may have important roles in this inhibitory activity in B16 melanoma cells. Our results suggest that tricin inhibits melanin biosynthesis with higher efficacy than arbutin, and it could be used as a whitening agent.

  9. In vitro CAPE inhibitory activity towards human AKR1C3 and the molecular basis.

    PubMed

    Li, Cuiyun; Zhao, Yining; Zheng, Xuehua; Zhang, Hong; Zhang, Liping; Chen, Yunyun; Li, Qing; Hu, Xiaopeng

    2016-06-25

    AKR1C3 is a critical enzyme for producing testosterone and 5α-DHT in the human body. Inhibiting AKR1C3 is a potential target for treating castration-resistant prostate cancer (CRPC). To find AKR1C3 inhibitors with a new molecular skeleton and binding mode, we analyzed the in vitro inhibitory activity of caffeic acid phenethyl ester (CAPE) and eight other phenolic acid analogues towards AKR1C3 and six other human AKR1 enzymes. We analyzed CAPE and octyl gallate interactions with AKR1C3 using X-ray crystallography, which provided a molecular basis for understanding the phenolic acid inhibitory activity and selectivity towards human AKR1s. PMID:27163852

  10. Polyketides from the Mangrove-Derived Endophytic Fungus Nectria sp. HN001 and Their α-Glucosidase Inhibitory Activity

    PubMed Central

    Cui, Hui; Liu, Yayue; Nie, Yang; Liu, Zhaoming; Chen, Senhua; Zhang, Zhengrui; Lu, Yongjun; He, Lei; Huang, Xishan; She, Zhigang

    2016-01-01

    Four new polyketides: nectriacids A–C (1–3) and 12-epicitreoisocoumarinol (4), together with three known compounds: citreoisocoumarinol (5), citreoisocoumarin (6), and macrocarpon C (7) were isolated from the culture of the endophytic fungus Nectria sp. HN001, which was isolated from a fresh branch of the mangrove plant Sonneratia ovata collected from the South China Sea. Their structures were determined by the detailed analysis of NMR and mass spectroscopic data. The absolute configuration of the stereogenic carbons for compound 4 was further assigned by Mosher’s ester method. All of the isolated compounds were tested for their α-glucosidase inhibitory activity by UV absorbance at 405 nm, and new compounds 2 and 3 exhibited potent inhibitory activity with IC50 values of 23.5 and 42.3 μM, respectively, which were more potent than positive control (acarbose, IC50, 815.3 μM). PMID:27136568

  11. Silk gland-specific proteinase inhibitor serpin16 from the Bombyx mori shows cysteine proteinase inhibitory activity.

    PubMed

    Guo, Peng-Chao; Dong, Zhaoming; Xiao, Li; Li, Tao; Zhang, Yan; He, Huawei; Xia, Qingyou; Zhao, Ping

    2015-01-30

    Serpins (serine proteinase inhibitors) are widely distributed in different species and are well known for their inhibitory activities towards serine proteinases. Here, we report the functional characterization of Bombyx mori serpin16. Expression analysis showed that serpin16 was specifically expressed at high levels in the silk gland at both the transcriptional and translational levels. Moreover, homology modeling and multi-sequence alignment suggested that serpin16 had a canonical serpin fold, but it contained a unique reactive center loop, which was obviously shorter than that of typical serpins. Inhibitory activity analyses revealed that the target proteinase of serpin18 is a cysteine proteinase, rather than a serine proteinase. Furthermore, a Michaelis complex model of serpin16 with its target proteinase was constructed to explain the structural basis of how serpin16 recognizes the cysteine proteinase and its target specificity.

  12. Determination of Plaque Inhibitory Activity of Adenine Arabinoside (9-β-d-Arabinofuranosyladenine) for Herpesviruses Using an Adenosine Deaminase Inhibitor

    PubMed Central

    Bryson, Yvonne; Connor, James D.; Sweetman, Lawrence; Carey, Sharen; Stuckey, Margaret A.; Buchanan, Robert

    1974-01-01

    The in vitro susceptibility of type 1 and type 2 strains of Herpesvirus hominis to 9-β-d-arabinofuranosyladenine (adenine arabinoside, ara-A) was measured in a system where deamination was inhibited. Under these conditions, it was possible to measure the activity of low concentrations of ara-A. It was determined that plaque inhibitory concentration for type 1 viruses was less than 3 μg/ml for all strains tested. The plaque inhibitory concentration for 7 of 10 type 2 strains was also less than 3 μg/ml. The method used identified and controlled the interaction between antiviral agent (ara-A) and the indicator system, human skin fibroblastic cells. Otherwise, metabolism of ara-A resulted in rapid enzymatic degradation and loss of antiviral activity. PMID:15828177

  13. Cadinane sesquiterpenes from Curcuma phaeocaulis with their inhibitory activities on nitric oxide production in RAW 264.7 cells.

    PubMed

    Ma, Jianghao; Wang, Ying; Liu, Yue; Gao, Suyu; Ding, Liqin; Zhao, Feng; Chen, Lixia; Qiu, Feng

    2015-06-01

    Four new cadinane-type sesquiterpenes named phacadinanes A-D (1-4) were isolated from the rhizomes of Curcuma phaeocaulis. Their structures were elucidated by 1D and 2D NMR, as well as accurate mass measurements. Compound 4 was the first example of a rare 4,5-seco-cadinane sesquiterpene isolated from the Zingiberaceae family. Furthermore, inhibitory effects of the isolated compounds on nitric oxide production in LPS-activated macrophages were evaluated. Compounds 1 and 2 showed strong inhibitory activities on NO production with IC50 values of 3.88±0.58 and 2.25±0.71 μM, respectively. A possible biogenetic pathway for 4,5-seco-cadinane sesquiterpene (4) was postulated.

  14. Polyketides from the Mangrove-Derived Endophytic Fungus Nectria sp. HN001 and Their α-Glucosidase Inhibitory Activity.

    PubMed

    Cui, Hui; Liu, Yayue; Nie, Yang; Liu, Zhaoming; Chen, Senhua; Zhang, Zhengrui; Lu, Yongjun; He, Lei; Huang, Xishan; She, Zhigang

    2016-05-01

    Four new polyketides: nectriacids A-C (1-3) and 12-epicitreoisocoumarinol (4), together with three known compounds: citreoisocoumarinol (5), citreoisocoumarin (6), and macrocarpon C (7) were isolated from the culture of the endophytic fungus Nectria sp. HN001, which was isolated from a fresh branch of the mangrove plant Sonneratia ovata collected from the South China Sea. Their structures were determined by the detailed analysis of NMR and mass spectroscopic data. The absolute configuration of the stereogenic carbons for compound 4 was further assigned by Mosher's ester method. All of the isolated compounds were tested for their α-glucosidase inhibitory activity by UV absorbance at 405 nm, and new compounds 2 and 3 exhibited potent inhibitory activity with IC50 values of 23.5 and 42.3 μM, respectively, which were more potent than positive control (acarbose, IC50, 815.3 μM).

  15. Inhibitory control of hippocampal inhibitory neurons

    PubMed Central

    Chamberland, Simon; Topolnik, Lisa

    2012-01-01

    Information processing within neuronal networks is determined by a dynamic partnership between principal neurons and local circuit inhibitory interneurons. The population of GABAergic interneurons is extremely heterogeneous and comprises, in many brain regions, cells with divergent morphological and physiological properties, distinct molecular expression profiles, and highly specialized functions. GABAergic interneurons have been studied extensively during the past two decades, especially in the hippocampus, which is a relatively simple cortical structure. Different types of hippocampal inhibitory interneurons control spike initiation [e.g., axo-axonic and basket cells (BCs)] and synaptic integration (e.g., bistratified and oriens–lacunosum moleculare interneurons) within pyramidal neurons and synchronize local network activity, providing a means for functional segregation of neuronal ensembles and proper routing of hippocampal information. Thus, it is thought that, at least in the hippocampus, GABAergic inhibitory interneurons represent critical regulating elements at all stages of information processing, from synaptic integration and spike generation to large-scale network activity. However, this raises an important question: if inhibitory interneurons are fundamental for network computations, what are the mechanisms that control the activity of the interneurons themselves? Given the essential role of synaptic inhibition in the regulation of neuronal activity, it would be logical to expect that specific inhibitory mechanisms have evolved to control the operation of interneurons. Here, we review the mechanisms of synaptic inhibition of interneurons and discuss their role in the operation of hippocampal inhibitory circuits. PMID:23162426

  16. Hypotensive, Angiotensin Converting Enzyme (ACE) Inhibitory and Diuretic Activities of the Aqueous-methanol Extract of Ipomoea reniformis

    PubMed Central

    Jabeen, Qaiser; Aslam, Naveed

    2013-01-01

    Ipomoea reniformis Roxb. (Convolvulaceae) is a small, weedy herb used for the management of cardiac problems in traditional systems of medicine in India and Pakistan. Objective of the present study was to investigate the hypotensive, diuretic and angiotensin converting enzyme (ACE) inhibitory activities of the aqueous-methanol (30:70) crude extract of the dried aerial parts of I. reniformis (Ir.Cr.) in rats. To record blood pressure lowering effects of the Ir.Cr, different doses of the extract were administered through jugular vein to the ketamine-diazepam anesthetized normotensive rats and blood pressure was recorded via carotid artery. ACE inhibitory activity of the extract was studied in-vitro; using hippuryl-l-histidyl-l-leucine as substrate, the product hippurate was quantified spectrophotometrically after reacting with cyanuric chloride/dioxane reagent. Effects of intraperitoneal administration of the extract on urine and urinary electrolyte excretion were also investigated in rats. The extract (Ir.Cr.) produced 21.51 ± 3.41, 28.99 ± 2.30, 53.34 ± 0.88 and 61.71 ± 3.37% fall in mean arterial blood pressure of the anesthetized rats at the doses of 0.1, 0.3, 1.0 and 3.0 mg/Kg, respectively. Ir.Cr. was found to have serum ACE inhibitory activity, with IC50 value of 422 ± 21.16 μg/mL. The extract also increased urine volume and urinary Na+ excretion significantly at the doses of 30 and 50 mg/Kg in rats. The study concludes that the crude extract of Ipomoea reniformis (Ir.Cr.) has hypotensive, ACE inhibitory and diuretic activities, which provide the scientific justification for the traditional uses of the plant as cardioprotective, antihypertensive and diuretic remedy. PMID:24523757

  17. Development of an antidiabetic formulation (ADJ6) and its inhibitory activity against α-amylase and α-glucosidase.

    PubMed

    Duraiswamy, Anand; Shanmugasundaram, Devanand; Sasikumar, Changam Sheela; Cherian, Sanjay M; Cherian, Kotturathu Mammen

    2016-07-01

    There has recently been much advancement in the diagnosis, treatment, and research of metabolic disorders, especially diabetes. Current research around the world is focused on finding an alternative source of treatment from natural resources for diabetic management, apart from the available synthetic medicines. The present study is a preliminary study of a polyherbal formulation using edible natural resources and an assessment of its antidiabetic activity. The formulation was screened for its phytochemical constituents, total phenols, flavonoids, and vitamin C content. It was also analyzed for its inhibitory effect against the digestive enzymes α-amylase and α-glucosidase, compared with the standard drug acarbose. The formulation showed the presence of major constituents such as steroids, cardiac glycosides, phenols, flavonoids, and saponins. It also had a high level of phenols (340 ± 2.5 mg/g), flavonoids (235.4 ± 8.3 mg/g), and vitamin C (470.8 ± 16.6 mg/g), and showed a half-maximal inhibitory concentration (IC50) value of 0.41 ± 0.03 mg/mL and 0.51 ± 0.01 mg/mL for amylase and glucosidase, respectively. The results showed that ADJ6 had a significant inhibitory activity on α-amylase and α-glucosidase; however, its inhibitory activity was less than that of acarbose. The plants that are formulated in ADJ6 possess potent antidiabetic activity. Thus, we found that ADJ6 is a potent lead for effective diabetic management; however, an evaluation of the formulation must be illustrated using an in vivo model. PMID:27419082

  18. Novel N-phenylcarbamothioylbenzamides with anti-inflammatory activity and prostaglandin E2 inhibitory properties

    PubMed Central

    Limban, Carmen; Missir, Alexandru Vasile; Fahelelbom, Khairi Mustafa Salem; Al-Tabakha, Moawia Mohammad; Caproiu, Miron Teodor; Sadek, Bassem

    2013-01-01

    A number of 2-((4-ethylphenoxy)methyl)-N-(substituted-phenylcarbamothioyl) benzamides (1a–h) were synthesized via reaction of 2-((4-ethylphenoxy)methyl)benzoyl isothiocyanate (2) as a key intermediate with several substituted primary aromatic amines. The new compounds were characterized by proton nuclear magnetic resonance (1H-NMR), carbon-13 nuclear magnetic resonance (13C-NMR), infrared spectrometry (IR), mass spectrometry (MS), and elemental analysis. The anti-inflammatory activity of 1a–h was investigated by acute carrageenan-induced paw edema in mice using the reference drug indomethacin. The results obtained indicated that, of the derivatives developed, 1a and 1d–h exhibited significantly higher anti-inflammatory activity (26.81%–61.45%) when compared with the reference drug indomethacin (22.43%) (P = 0.0490 for 1a, 0.0015 for 1d, 0.0330 for 1f, and P < 0.001 for 1e and 1h). Moreover, the ulcer incidence of 20% for 1e and 1h was clearly lower when compared with the indomethacin group (in which the ulcer incidence was 80%). Of particular note, the ulcer index of 0.2 for 1e was significantly less than that in the indomethacin group (0.6, P = 0.014). Additionally, prostaglandin E2 (PGE2) inhibitory properties were found to be high with 1e (68.32 pg/mL), significantly different from those of the placebo group (530.13 pg/mL, P < 0.001), and equipotent to the effect observed in the indomethacin-pretreated group (96.13 pg/mL, P > 0.05). Moreover, the PGE2 level of 54.15 pg/mL with 1h was also significantly different from that of the placebo group (P < 0.001) and of the indomethacin group (P < 0.05). The significant inhibition of PGE2 observed with 1e (68.32 pg/mL) and 1h (54.15 pg/mL) agree with their observed ulcer incidences. Our overall findings for N-phenylcarbamothioylbenzamides 1a–h clearly suggest that the compounds exhibit an anti-inflammatory effect, potently inhibit PGE2 synthesis, and markedly demonstrate low ulcer incidence. PMID:24039398

  19. Angiotensin I converting enzyme (ACE) inhibitory activity of hetero-chitooligosaccharides prepared from partially different deacetylated chitosans.

    PubMed

    Park, Pyo-Jam; Je, Jae-Young; Kim, Se-Kwon

    2003-08-13

    Angiotensin I converting enzyme (ACE) inhibitory activity of hetero-chitooligosaccharides (hetero-COSs) prepared from partially different deacetylated chitosans was investigated. Partially deacetylated chitosans, 90, 75, and 50% deacetylated chitosan, were prepared from crab chitin by N-deacetylation with 40% sodium hydroxide solution for durations. In addition, nine kinds of hetero-COSs with relatively high molecular masses (5000-10 000 Da; 90-HMWCOSs, 75-HMWCOSs, and 50-HMWCOSs), medium molecular masses (1000-5000 Da; 90-MMWCOSs, 75-MMWCOSs, and 50-MMWCOSs), and low molecular masses (below 1000 Da; 90-LMWCOSs, 75-LMWCOSs, and 50-LMWCOSs) were prepared using an ultrafiltration membrane bioreactor system. ACE inhibitory activity of hetero-COSs was dependent on the degree of deacetylation of chitosans. 50-MMWCOSs that are COSs hydrolyzed from 50% deacetylated chitosan, the relatively lowest degree of deacetylation, exhibited the highest ACE inhibitory activity, and the IC(50) value was 1.22 +/- 0.13 mg/mL. In addition, the ACE inhibition pattern of the 50-MMWCOSs was investigated by Lineweaver-Burk plots, and the inhibition pattern was found to be competitive.

  20. Separate activation of fast and slow inhibitory postsynaptic potentials in rat neocortex in vitro.

    PubMed Central

    Benardo, L S

    1994-01-01

    Synaptic inhibition was investigated by stimulating inhibitory neurones with focal microapplications of glutamate, while recording from layer V pyramidal neurones of rat somatosensory cortical slices. One class of inhibitory postsynaptic potentials (IPSPs) thus elicited was characterized as a fast, chloride-mediated, GABAA IPSP in part by its fast time-to-peak (mean 2.5 ms) and brief duration, but primarily on the basis of its reversal potential at -68 mV, and its blockade by picrotoxin. The average peak amplitude for these fast IPSPs was -1.5 mV, measured at -60 mV. The peak conductance calculated for these events was about 10 nS. The conductance change associated with the maximal fast inhibitory postsynaptic potential resulting from electrical stimulation of afferent pathways ranged up to 116 nS. A second class of IPSP was encountered much less frequently. These glutamate-triggered events were characterized as slow, potassium-mediated GABAB IPSPs partly because of their longer times-to-peak (mean, 45 ms) and duration, but especially because of their extrapolated equilibrium potential at about -89 mV and blockade by 2-hydroxysaclofen. The average peak amplitude for these slow IPSPs was -2.3 mV, measured at -60 mV. The peak conductance for these events was about 8 nS. IPSPs resulting from the excitation of individual inhibitory interneurones were elicited by glutamate microapplication at particular locations relative to recording sites. Both fast and slow IPSPs were generated, but these occurred as separate events, and mixed responses were never seen. Thus, the two mechanistically distinct types of IPSPs which result from GABA interaction at GABAA and GABAB receptors on neocortical neurones may be mediated by separate classes of inhibitory neurones. PMID:7913968

  1. 3-Prenyl luteolin, a new prenylated flavone with melanin biosynthesis inhibitory activity from wood of Artocarpus heterophyllus.

    PubMed

    Arung, Enos Tangke; Shimizu, Kuniyoshi; Tanaka, Hiroyuki; Kondo, Ryuichiro

    2010-09-01

    In our efforts to find new whitening agent from natural resources, we focused on wood of Artocarpus heterophyllus which shows anti-melanogenesis activity. By activity-guided fractionation of A. heterophyllus wood extract, a new prenylated flavonoid, 3-prenyl luteolin (1) was isolated. The IC(50) of mushroom tyrosinase inhibitory activity of 1 was 76.3 microM. The results of the comparison with that of luteolin showed the prenyl substituent at C-3 position of 1 play an important role for revealing tyrosinase inhibition. In melanin formation inhibition on B16 melanoma cells, IC(50) of 1 was 56.7 microM with less cytotoxicity.

  2. Inhibitory effects of Tyrphostin AG-related compounds on oxidative stress-sensitive transient receptor potential channel activation.

    PubMed

    Toda, Takahiro; Yamamoto, Shinichiro; Yonezawa, Ryo; Mori, Yasuo; Shimizu, Shunichi

    2016-09-01

    Some transient receptor potential (TRP) proteins including TRPA1, TPRM2 and TRPV1 are oxidative stress-sensitive Ca(2+)-permeable channels. Ca(2+) signaling via these TRP channels activated by oxidative stress has been implicated in the aggravation of various inflammatory diseases and pain sensation. We recently reported that Tyrphostin AG490 exerted inhibitory effects on H2O2-induced TRPM2 activation by scavenging the hydroxyl radical. In order to identify stronger inhibitors of oxidative stress-sensitive TRP channels than AG490, we examined the inhibitory effects of Tyrphostin AG-related compounds on H2O2-induced TRP channel activation in human embryonic kidney 293 cells expressing TRP channels. AG555 and AG556 blocked the activation of TRPM2 by H2O2 more strongly than AG490. Regarding TRPV1 and TRPA1, none of the three compounds tested affected H2O2-induced TRPV1 activation; however, AG555 and AG556 reduced H2O2-induced TRPA1 activation more than AG490. Thus, we herein identified AG555 and AG556 as new compounds that exert stronger inhibitory effects on H2O2-induced TRPM2 and TRPA1 activation than AG490. Edaravone, a hydroxyl radical scavenger used in the treatment of cerebral hemorrhage and cerebral infarction, did not affect H2O2-induced TRPM2 or TRPA1 activation. AG555 and AG556 may be useful seed compounds as therapeutic agents for several TRP-related diseases associated with oxidative stress. PMID:27238971

  3. Distinct inhibitory neurons exert temporally specific control over activity of a motoneuron receiving concurrent excitation and inhibition.

    PubMed

    Sasaki, Kosei; Brezina, Vladimir; Weiss, Klaudiusz R; Jing, Jian

    2009-09-23

    Recent work suggests that concurrent excitation and inhibition originating in central pattern generators (CPGs) may be used to control rhythmic motoneuronal activity. The specific roles that the inhibition plays in such cases are not well understood, however, in part because of the lack of identification of presynaptic inhibitory neurons. Here we demonstrate that, in the Aplysia feeding CPG, inhibitory inputs may be critical for flexible control of the activity of motoneurons in different forms of behavior. The feeding CPG generates ingestive and egestive motor programs, differing in the high and low activity, respectively, of the motoneuron B8 during the retraction phase of the programs. We show that, during retraction, B8 receives concurrent excitation and inhibition that produces a high-conductance state. The inhibition originates in two types of CPG neurons, B4/5 and B70, that are more active in egestion than ingestion and play a role in suppressing B8 activity during egestion. In turn, the activities of both B4/5 and B70 are suppressed by the ingestion-promoting descending interneuron CBI-3 (for cerebral-buccal interneuron 3). Thus, concurrent excitation and inhibition may be an effective means of controlling motoneuronal activity in a behavior-dependent manner. More detailed analyses reveal, furthermore, that B4/5 and B70 exert complementary actions by acting preferentially in the early and late part of retraction, respectively. Thus, the use of multiple neurons to generate inhibitory inputs to motoneurons that receive concurrent excitation and inhibition brings an additional level of flexibility that allows a temporally specific control of motoneuronal activity within a single phase of motor programs.

  4. Inhibitory effects of heterotopic noxious counter-stimulation on perception and brain activity related to Aβ-fibre activation.

    PubMed

    Rustamov, Nabi; Tessier, Jessica; Provencher, Benjamin; Lehmann, Alexandre; Piché, Mathieu

    2016-07-01

    Heterotopic noxious counter-stimulation (HNCS) inhibits pain and pain processes through cerebral and cerebrospinal mechanisms. However, it is unclear whether HNCS inhibits non-nociceptive processes, which needs to be clarified for a better understanding of HNCS analgesia. The aim of this study was to examine the effects of HNCS on perception and scalp somatosensory evoked potentials (SEPs). Seventeen healthy volunteers participated in two counter-balanced sessions, including non-nociceptive (selective Aβ-fibre activation) or nociceptive electrical stimulation, combined with HNCS. HNCS was produced by a 20-min cold pressor test (left hand) adjusted individually to produce moderate pain (mean ± SEM: 42.5 ± 5.3 on a 0-100 scale, where 0 is no pain and 100 the worst pain imaginable). Non-nociceptive electrical stimulation was adjusted individually at 80% of pain threshold and produced a tactile sensation in every subject. Nociceptive electrical stimulation was adjusted individually at 120% of RIII-reflex threshold and produced moderate pain (45.3 ± 4.5). Shock sensation was significantly decreased by HNCS compared with baseline for non-nociceptive (P < 0.001) and nociceptive (P < 0.001) stimulation. SEP peak-to-peak amplitude at Cz was significantly decreased by HNCS for non-nociceptive (P < 0.01) and nociceptive (P < 0.05) stimulation. These results indicate that perception and brain activity related to Aβ-fibre activation are inhibited by HNCS. The mechanisms of this effect remain to be investigated to clarify whether it involves inhibition of spinal wide-dynamic-range neurons by diffuse noxious inhibitory controls, supraspinal processes or both. PMID:27086672

  5. Polyphenols from the stems of Morus alba and their inhibitory activity against nitric oxide production by lipopolysaccharide-activated microglia.

    PubMed

    Rivière, Céline; Krisa, Stéphanie; Péchamat, Laurent; Nassra, Merian; Delaunay, Jean-Claude; Marchal, Axel; Badoc, Alain; Waffo-Téguo, Pierre; Mérillon, Jean-Michel

    2014-09-01

    Neuroinflammatory processes are involved in the pathogenesis of many neurodegenerative disorders. Microglial cells, the main immune cells of the central nervous system, represent a target of interest to search for naturally occurring anti-inflammatory products. In this study, we evaluated the anti-inflammatory properties of polyphenols obtained from the stems of Morus alba. This edible species, known as white mulberry, is frequently studied because of its traditional use in Asian medicine and its richness in different types of polyphenols, some of which are known to be phytoalexins. One new coumarin glycoside, isoscopoletin 6-(6-O-β-apiofuranosyl-β-glucopyranoside) (1) was mainly isolated by CPC (centrifugal partition chromatography) from this plant, together with seven known polyphenols (2-8). Their structures were established on the basis of spectroscopic analyses including extensive 2D NMR studies. The eight isolated compounds were evaluated for their inhibitory activities on nitric oxide (NO) production in lipopolysaccharide (LPS)-induced BV-2 microglial cells. The absence of cell toxicity is checked by a MTT assay.

  6. Chemical investigation of Cyperus distans L. and inhibitory activity of scabequinone in seed germination and seedling growth bioassays.

    PubMed

    Vilhena, Karyme S S; Guilhon, Giselle Maria Skelding Pinheiro; Zoghbi, Maria das Graças B; Santos, Lourivaldo Silva; Souza Filho, Antonio Pedro Silva

    2014-01-01

    Chemical investigation of the rhizomes of Cyperus distans (Cyperaceae) led to the identification of α-ciperone, cyperotundone and scabequinone, besides other common constituents. Complete assignment of the (13)C NMR data of scabequinone is being published for the first time. The inhibitory effects of C. distans extracts and scabequinone on the seed germination and seedling growth of Mimosa pudica, Senna obtusifolia and Pueraria phaseoloides were evaluated. Seed germination inhibition bioassay revealed that S. obtusifolia (52-53%) was more sensitive to the hexane and the methanol extracts at 1% than M. pudica (0-10%). Scabequinone at 250 mg L⁻¹ displayed seed germination inhibitions more than 50% and radicle growth reduction of more than 35% of the test species S. obtusifolia and P. phaseoloides, while the hypocotyl growth of M. pudica was significantly affected (>50%) by the quinone at the same concentration. These results demonstrate that scabequinone contributes to the overall inhibitory activities of C. distans.

  7. Chemical investigation of Cyperus distans L. and inhibitory activity of scabequinone in seed germination and seedling growth bioassays.

    PubMed

    Vilhena, Karyme S S; Guilhon, Giselle Maria Skelding Pinheiro; Zoghbi, Maria das Graças B; Santos, Lourivaldo Silva; Souza Filho, Antonio Pedro Silva

    2014-01-01

    Chemical investigation of the rhizomes of Cyperus distans (Cyperaceae) led to the identification of α-ciperone, cyperotundone and scabequinone, besides other common constituents. Complete assignment of the (13)C NMR data of scabequinone is being published for the first time. The inhibitory effects of C. distans extracts and scabequinone on the seed germination and seedling growth of Mimosa pudica, Senna obtusifolia and Pueraria phaseoloides were evaluated. Seed germination inhibition bioassay revealed that S. obtusifolia (52-53%) was more sensitive to the hexane and the methanol extracts at 1% than M. pudica (0-10%). Scabequinone at 250 mg L⁻¹ displayed seed germination inhibitions more than 50% and radicle growth reduction of more than 35% of the test species S. obtusifolia and P. phaseoloides, while the hypocotyl growth of M. pudica was significantly affected (>50%) by the quinone at the same concentration. These results demonstrate that scabequinone contributes to the overall inhibitory activities of C. distans. PMID:24941231

  8. Evaluation of copper-dependent proteasome-inhibitory and apoptosis-inducing activities of novel pyrrolidine dithiocarbamate analogues.

    PubMed

    Yu, Zhiyong; Wang, Fei; Milacic, Vesna; Li, Xiaofeng; Cui, Qiuzhi Cindy; Zhang, Bin; Yan, Bing; Dou, Q Ping

    2007-12-01

    Apoptosis has a central role in the pathogenesis of many human diseases, one of which is cancer. One of the most important strategies to regulate apoptosis is via the ubiquitin-proteasome pathway. It has been shown that inhibition of proteasomal chymotrypsin-like activity is a strong apoptosis-inducing stimulus and that actively proliferating cancer cells are more sensitive to proteasome inhibitors than normal or untransformed cells. Dithioscarbamates are a class of metal-chelating compounds with various applications in medicine. We reported previously that certain members of dithiocarbamates, such as pyrrolidine dithiocarbamate (PDTC), diethyldithiocarbamate and disulfiram, are able to bind with tumor cellular copper, forming an active complex with proteasome-inhibitory, apoptosis-inducing and anti-cancer activities. In the current study, we synthesized eight PDTC analogues with substitutions made to the pyrrolidine ring and studied their structure-activity relationships. We found that substitution of the pyrrolidine ring with piperidine had almost no effect on their proteasome-inhibitory and anti-proliferative potencies in human breast cancer cells. However, after the pyrrolidine ring was substituted with morpholine, the activity of the mixtures slightly decreased but was completely lost when piperazine with the attached ethyl group was used for the substitution. This structure-activity relationship was confirmed by the results generated with the corresponding copper complexes. Our data further support the novel concept of using accumulated copper in human cancer cells as a selective approach for chemotherapy. PMID:17982703

  9. Two new phthalides with BuChE inhibitory activity from Ligusticum chuanxiong.

    PubMed

    Huang, Jian; Lu, Xiao-Qing; Lu, Jin; Li, Guo-Yu; Wang, Hang-Yu; Li, Li-Hong; Lin, Rui-Chao; Wang, Jin-Hui

    2013-01-01

    Two new phthalides, chuanxiongdiolides A and B, were isolated from the roots of Ligusticum chuanxiong Hort. Their structures were established by UV, IR, 1D (¹H, ¹³C) and 2D (HSQC, ¹H-¹H COSY, HMBC, NOESY) NMR, and HR-ESI-MS methods, and their absolute configurations were assigned via circular dichroism exciton chirality. The two compounds showed different degrees of inhibitory effects against butyrylcholine esterase. PMID:24279751

  10. Norfriedelins A-C with acetylcholinesterase inhibitory activity from acerola tree (Malpighia emarginata).

    PubMed

    Liu, Jie-Qing; Peng, Xing-Rong; Li, Xu-Yang; Li, Ting-Zhao; Zhang, Wei-Ming; Shi, Lei; Han, Jiang; Qiu, Ming-Hua

    2013-04-01

    Three novel norfriedelanes, A-C (1-3), were isolated from the branches and roots of Malpighia emarginata . Their structures and absolute configurations were determined by 1D and 2D NMR techniques and X-ray crystallographic analysis. Norfriedelin A (possessing an α-oxo-β-lactone group) and norfriedelin B (with a keto-lactone group) showed acetylcholinesterase inhibitory effects with the IC50 values of 10.3 and 28.7 μM, respectively.

  11. Slow active potentials in ventral inhibitory motor neurons of the nematode Ascaris.

    PubMed

    Angstadt, J D; Stretton, A O

    1989-12-01

    The ability of ventral inhibitory motor neurons of the nematode Ascaris to generate slow depolarizing potentials was investigated using intracellular recording and current injection. In quiescent cells, regenerative depolarizations with peak amplitudes of approximately 20 mV and durations of several 100 ms were evoked in response to brief depolarizing current pulses. Repetitive slow potentials were produced in response to sustained depolarizing currents in a threshold-dependent manner. Repetitive slow potentials also occurred spontaneously, exhibiting cycle periods of about 700 ms. The ability of inhibitory motor neurons to generate slow potentials was blocked by addition of Co++, Cd++, or other Ca-channel blockers to the saline but not by TTX or substitution of Na+ with Tris. The amplitude and duration of slow potentials were increased in the presence of Ba++, Sr++, and TEA. Spontaneous slow potentials exhibited characteristics expected of intrinsically generated oscillations, including frequency modulation by injection of prolonged offset currents, phase resetting by brief current pulses, and suppression by strong hyperpolarization. Slow potentials appear to be generated in the ventral nerve cord processes and/or cell body of the motor neuron, and they produce rhythmic inhibitory postsynaptic potentials in ventral muscle cells. Slow potentials may therefore contribute to locomotory or other motor behaviors of the animal. PMID:2607486

  12. Biotransformation of finasteride by Ocimum sanctum L., and tyrosinase inhibitory activity of transformed metabolites: experimental and computational insights.

    PubMed

    Ali, Sajid; Nisar, Muhammad; Iriti, Marcello; Shah, Mohammad Raza; Mahmud, Maqsood; Ali, Ihsan; Khan, Inamullah

    2014-12-01

    Transformation of Finasteride (I) by cell suspension cultures of Ocimum sanctum L. was investigated. Fermentation of compound (I) with O. sanctum afforded three oxidized derivatives, 16β-hydroxyfinasteride (II), 11α-hydroxyfinasteride (III) and 15β-hydroxyfinasteride (IV). Among these metabolites, compound (II) was a new metabolite. Compound (I) and its derivatives were studied for their tyrosinase inhibition assay. All test compounds exhibited significant activity compared to standard drug kojic acid, with compound IV being the most potent member with an IC50 of 1.87μM. Molecular docking revealed significant molecular interactions behind the potent tyrosinase inhibitory activity of the tested compounds. PMID:25159102

  13. Inhibitory activity of a nisin-producing starter culture on Listeria innocua in raw ewes milk Manchego cheese.

    PubMed

    Rodríguez, E; Gaya, P; Nuñez, M; Medina, M

    1998-01-01

    The inhibitory activity of nisin-producing Lactococcus lactis subsp. lactis ESI 515 on the survival of Listeria innocua during ripening of raw ewes milk Manchego cheese was investigated. After 60 days of ripening, counts of L. innocua in cheese were 4.08 log units lower than the control when Lc. lactis subsp. lactis ESI 515 was used as a single-strain starter. Nisin activity was detected in cheeses manufactured with Lc. lactis subsp. lactis ESI 515 throughout the ripening period. PMID:9580244

  14. Inhibitory activity of oxyresveratrol on wild-type and drug-resistant varicella-zoster virus replication in vitro.

    PubMed

    Sasivimolphan, Pattaraporn; Lipipun, Vimolmas; Likhitwitayawuid, Kittisak; Takemoto, Masaya; Pramyothin, Pornpen; Hattori, Masao; Shiraki, Kimiyasu

    2009-10-01

    The anti-herpes simplex virus (HSV) compound, oxyresveratrol, purified from a Thai traditional medicinal plant of Artocarpus lakoocha, was evaluated for its anti-varicella-zoster virus (VZV) activity. This compound exhibited IC(50) values (50%-inhibitory concentrations for virus plaque formation) of 12.82, 12.80, 12.99 and 12.82 microg/ml against wild type, thymidine kinase-deficient and two types of DNA polymerase mutants with acyclovir-resistance, respectively. Thus oxyresveratrol showed a broad spectrum of anti-VZV activity with a mechanism of action different from that of acyclovir.

  15. Phosphorylation of the Arp2 subunit relieves auto-inhibitory interactions for Arp2/3 complex activation.

    PubMed

    Narayanan, Arjun; LeClaire, Lawrence L; Barber, Diane L; Jacobson, Matthew P

    2011-11-01

    Actin filament assembly by the actin-related protein (Arp) 2/3 complex is necessary to build many cellular structures, including lamellipodia at the leading edge of motile cells and phagocytic cups, and to move endosomes and intracellular pathogens. The crucial role of the Arp2/3 complex in cellular processes requires precise spatiotemporal regulation of its activity. While binding of nucleation-promoting factors (NPFs) has long been considered essential to Arp2/3 complex activity, we recently showed that phosphorylation of the Arp2 subunit is also necessary for Arp2/3 complex activation. Using molecular dynamics simulations and biochemical assays with recombinant Arp2/3 complex, we now show how phosphorylation of Arp2 induces conformational changes permitting activation. The simulations suggest that phosphorylation causes reorientation of Arp2 relative to Arp3 by destabilizing a network of salt-bridge interactions at the interface of the Arp2, Arp3, and ARPC4 subunits. Simulations also suggest a gain-of-function ARPC4 mutant that we show experimentally to have substantial activity in the absence of NPFs. We propose a model in which a network of auto-inhibitory salt-bridge interactions holds the Arp2 subunit in an inactive orientation. These auto-inhibitory interactions are destabilized upon phosphorylation of Arp2, allowing Arp2 to reorient to an activation-competent state. PMID:22125478

  16. Ex vivo digestion of carp muscle tissue--ACE inhibitory and antioxidant activities of the obtained hydrolysates.

    PubMed

    Borawska, J; Darewicz, M; Vegarud, G E; Iwaniak, A; Minkiewicz, P

    2015-01-01

    In the digestive tract of humans, bioactive peptides, i.e. protein fragments impacting the physiological activity of the body, may be released during the digestion of food proteins, including those of fish. The aim of the study was to establish the method of human ex vivo digestion of carp muscle tissue and evaluate the angiotensin I-converting enzyme inhibitory and antioxidant activities of hydrolysates obtained after digestion. It was found that the hydrolysates of carp muscle tissue obtained with the three-stage method of simulated ex vivo digestion showed ACE inhibitory as well as antioxidative activities. It was demonstrated that the degree of hydrolysis depended on the duration of individual stages and the degree of comminution of the examined material. Although the applied gastric juices initiated the process of hydrolysis of carp muscle tissue, the duodenal juices caused a rapid increase in the amount of hydrolysed polypeptide bonds. The antihypertensive and antioxidative activities of the hydrolysates of carp muscle tissue increased together with progressive protein degradation. However, the high degree of protein hydrolysis does not favour an increase in the activity of free radical scavenging. The presented results are an example of the first preliminary screening of the potential health-promoting biological activity of carp muscle tissue in an ex vivo study.

  17. Isolation, diversity and acetylcholinesterase inhibitory activity of the culturable endophytic fungi harboured in Huperzia serrata from Jinggang Mountain, China.

    PubMed

    Wang, Ya; Lai, Zheng; Li, Xi-Xi; Yan, Ri-Ming; Zhang, Zhi-Bin; Yang, Hui-Lin; Zhu, Du

    2016-02-01

    Huperzia serrata has many important medicinal properties with proven pharmacological potential. Some of these properties may be mediated by its endophytic fungi. To test this hypothesis, in the present study, we provided a first insights into evaluating the species composition and acetylcholinesterase (AChE) inhibitory activity of the culturable endophytic fungi of H. serrata from the regional at Jinggang Mountain in southeastern China. A total number of 885 fungal isolates distributed across 44 genera and 118 putative species were obtained from 1422 fragments of fine H. serrata roots, stems and leaves base on ITS-rDNA sequences BLAST analysis. The endophytic fungi were phylogenetically diverse and species-rich, with high rate of colonization and isolation. The assemble of endophytic fungi consisted mainly of Ascomycota (97.15%), followed by Basidiomycota (1.92%) and unknown fungal species (0.90%). Colletotrichum (64.29%), Phyllosticta (3.39%), Hypoxylon (2.81%), Xylaria (2.25%) and Nigrospora (2.04%) were the most abundant genera, whereas the remaining genera were infrequent groups. Although, roots yielded low abundance strains, the diverse and species-rich were both higher than that of stems and leaves. In addition, out of the 247 endophytic fungi strains determinated, 221 fungal extracts showed AChE inhibition activities in vitro. Among them, 22 endophytic fungi strains achieved high inhibitory activity (≥50%) on AChE which belongs to 13 genera and five incertae sedis strains. Four endophytic fungi designated as JS4 (Colletotrichum spp.), FL14 (Ascomycota spp.), FL9 (Sarcosomataceae spp.) and FL7 (Dothideomycetes spp.) were displayed highly active (≥80%) against AChE, which the inhibition effects were even more intense than the positive control. Our findings highlight that H. serrata grown in Jinggang Mountain harbors a rich and fascinating endophytic fungus community with potential AChE inhibitory activity, which could further broaden the natural

  18. A Double WAP Domain-Containing Protein Es-DWD1 from Eriocheir sinensis Exhibits Antimicrobial and Proteinase Inhibitory Activities

    PubMed Central

    Guo, Xiao-Nv; Yu, Ai-Qing; Wu, Min-Hao; Tan, Shang-Jian; Zhu, You-Ting; Li, Wei-Wei; Wang, Qun

    2013-01-01

    Whey acidic proteins (WAP) belong to a large gene family of antibacterial peptides, which are critical in the host immune response against microbial invasion. The common feature of these proteins is a single WAP domain maintained by at least one four-disulfide core (4-DSC) structure rich in cysteine residues. In this study, a double WAP domain (DWD)-containing protein, Es-DWD1, was first cloned from the Chinese mitten crab (Eriocheirsinensis). The full-length Es-DWD1cDNA was 1193 bp, including a 411 bp open reading frame (ORF) encoding 136 amino acids with a signal peptide of 22 amino acids in the N-terminus. A comparison with other reported invertebrate and vertebrate sequences revealed the presence of WAP domains characteristic of WAP superfamilies. As determined by quantitative real-time RT-PCR, Es-DWD1 transcripts were ubiquitously expressed in all tissues, but it was up-regulated in hemocytes post-challenge with pathogen-associated molecular patterns (PAMPs). The mature recombinant Es-DWD1 (rEs-DWD1) protein exhibited different binding activities to bacteria and fungus. Moreover, rEs-DWD1 could exert agglutination activities against Bacillus subtilis and Pichiapastoris and demonstrated inhibitory activities against the growth of Staphylococcus aureus, Aeromonas hydrophila and P. pastoris. Furthermore, rEs-DWD1 showed a specific protease inhibitory activity in B. subtilis. Coating of rEs-DWD1 onto agarose beads enhanced encapsulation of the beads by crab hemocytes. Collectively, the results suggest that Es-DWD1 is a double WAP domain containing protein with antimicrobial and proteinase inhibitory activities, which play significant roles in the immunity of crustaceans. PMID:23967346

  19. Acetylcholinesterase and insect growth inhibitory activities of Gutierrezia microcephala on fall armyworm Spodoptera frugiperda J.E. Smith.

    PubMed

    Calderón, J S; Céspedes, C L; Rosas, R; Gómez-Garibay, F; Salazar, J R; Lina, L; Aranda, E; Kubo, I

    2001-01-01

    From the aerial parts of Gutierrezia microcephala (Asteraceae), four oxyflavones were isolated, namely 5,7,2'-trihydroxy-3,6,8,4',5'-pentamethoxyflavone (1); 5,7,4'-trihydroxy-3,6,8-trimethoxyflavone (2); 5,7,2',4'-tetrahydroxy-3,6,8,5'-tetramethoxyflavone (3); 5,2'-dihydroxy-3,6,7,8,4',5'-hexamethoxyflavone (4), and an ent-clerodane, bacchabolivic acid (5). Compounds 1-5, the synthetic methyl ester (6), n-hexane and MeOH extracts were evaluated against the fall armyworm (Spodoptera frugiperda). Gedunin, a known insect growth regulator isolated from Cedrela spp. was used as a positive control. When tested for activity on neonate larvae into the no-choice artificial diet bioassay, flavone (1), clerodane (5), its methyl ester (6), MeOH and n-hexane extracts caused significant larval mortality with MC50 of 3.9, 10.7, 3.46, 7.95 and 7.5 ppm at 7 days, respectively, as well as growth reduction. They also increased the development time of surviving larvae and a significant delay in time to pupation and adult emergence. Acute toxicity against adults of S. frugiperda was also found, 5, 6, gedunin and n-hexane extract had the most potent activity with LD50 value of 6.59, 15.05, 10.78, and 12.79 ppm, respectively. In addition, MeOH, n-hexane extracts, 5, 6 and gedunin caused acetylcholinesterase inhibition with 93.7, 100, 90.2, 62.0 and 100% at 50.0 ppm, respectively; whereas 1-4 exhibited only moderate inhibitory activity. Compounds 1, 5 and 6 showed inhibitory activities comparable with gedunin. These compounds could be responsible of the insect growth inhibitory activity of this plant. PMID:11421454

  20. Potential inhibitory effect of herbal medicines on rat hepatic cytochrome P450 2D gene expression and metabolic activity.

    PubMed

    Al-Jenoobi, F I; Korashy, H M; Ahad, A; Raish, M; Al-Mohizea, A M; Alam, M A; Al-Suwayeh, S A; Alkharfy, K M

    2014-11-01

    The aim of current study was to investigate the effect of some commonly used medicinal herbs on the regulation of rat CYP2D gene expression and its metabolic activity. Wistar albino rats were treated for seven consecutive days with selected doses of five commonly used herbs (Trigonella foenum-graecum, Ferula asafoetida, Nigella sativa, Commiphora myrrha and Lepidium sativum). Thereafter, rat livers were harvested and CYP2D mRNA levels were determined by RT-PCR. The metabolic activity of CYP2D was performed on rat hepatic microsomes using dextromethorphan as specific substrate. All investigated herbs produced inhibition of CYP2D mRNA expression and metabolic activity. The inhibitory potential of investigated herbs on rat CYP2D mRNA was in the following order: Commiphora myrrha > Nigella sativa > Lepidium sativum > Trigonella foenum-graecum > Ferula asafoetida. Whereas, the inhibitory potential of investigated herbs on CYP2D mediated enzyme metabolic activity was found in following order: Nigella sativa > Lepidium sativum > Trigonella foenum-graecum > Commiphora myrrha > Ferula asafoetida. The current study shows that only used herbs reduce CYP2D activity in rat liver microsomes at the transcriptional levels. Such effects could lead to undesirable pharmacological effects of clinically used low therapeutic index CYP2D substrate drugs.

  1. Concerted regulation of inhibitory activity of alpha 1-antitrypsin by the native strain distributed throughout the molecule.

    PubMed

    Seo, Eun Joo; Lee, Cheolju; Yu, Myeong-Hee

    2002-04-19

    The native forms of common globular proteins are in their most stable state but the native forms of plasma serpins (serine protease inhibitors) show high energy state interactions. The high energy state strain of alpha(1)-antitrypsin, a prototype serpin, is distributed throughout the whole molecule, but the strain that regulates the function directly appears to be localized in the region where the reactive site loop is inserted during complex formation with a target protease. To examine the functional role of the strain at other regions of alpha(1)-antitrypsin, we increased the stability of the molecule greatly via combining various stabilizing single amino acid substitutions that did not affect the activity individually. The results showed that a substantial increase of stability, over 13 kcal mol(-1), affected the inhibitory activity with a correlation of 11% activity loss per kcal mol(-1). Addition of an activity affecting single residue substitution in the loop insertion region to these very stable substitutions caused a further activity decrease. The results suggest that the native strain of alpha(1)-antitrypsin distributed throughout the molecule regulates the inhibitory function in a concerted manner. PMID:11834734

  2. Differential involvement of excitatory and inhibitory neurons of cat motor cortex in coincident spike activity related to behavioral context.

    PubMed

    Putrino, David; Brown, Emery N; Mastaglia, Frank L; Ghosh, Soumya

    2010-06-01

    To assess temporal associations in spike activity between pairs of neurons in the primary motor cortex (MI) related to different behaviors, we compared the incidence of coincident spiking activity of task-related (TR) and non-task-related (NTR) neurons during a skilled motor task and sitting quietly in adult cats (Felis domestica). Chronically implanted microwires were used to record spike activity of MI neurons in four animals (two male and two female) trained to perform a skilled reaching task or sit quietly. Neurons were identified as TR if spike activity was modulated during the task (and NTR if not). Based on spike characteristics, they were also classified as either regular-spiking (RS, putatively excitatory) or fast-spiking (FS, putatively inhibitory) neurons. Temporal associations in the activities of simultaneously recorded neurons were evaluated using shuffle-corrected cross-correlograms. Pairs of NTR and TR neurons showed associations in their firing patterns over wide areas of MI (representing forelimb and hindlimb movements) during quiet sitting, more commonly involving RS neurons. During skilled task performance, however, significantly coincident firing was seen almost exclusively between TR neurons in a smaller part of MI (representing forelimb movements), involving mainly FS neurons. The findings of this study show evidence for widespread interactions in MI when the animal sits quietly, which changes to a more specific and restricted pattern of interactions during task performance. Different populations of excitatory and inhibitory neurons appear to be synchronized during skilled movement and quiet sitting.

  3. In vitro α-amylase inhibitory activity and in vivo hypoglycemic effect of methanol extract of Citrus macroptera Montr. fruit

    PubMed Central

    Uddin, Nizam; Hasan, Md. Rakib; Hossain, Md. Monir; Sarker, Arjyabrata; Hasan, A.H.M. Nazmul; Islam, A.F.M. Mahmudul; Chowdhury, Mohd. Motaher H.; Rana, Md. Sohel

    2014-01-01

    Objective To investigate the therapeutic effects of methanol extract of Citrus macroptera Montr.fruit in α-amylase inhibitory activity (in vitro) and hypoglycemic activity in normal and glucose induced hyperglycemic rats (in vivo). Methods Fruits of Citrus macroptera without rind was extracted with pure methanol following cold extraction and tested for presence of phytochemical constituents, α-amylase inhibitory activity, and hypoglycemic effect in normal rats and glucose induced hyperglycemic rats. Results Presence of saponin, steroid and terpenoid were identified in the extract. The results showed that fruit extract had moderate α-amylase inhibitory activity [IC50 value=(3.638±0.190) mg/mL] as compared to acarbose. Moreover at 500 mg/kg and 1 000 mg/kg doses fruit extract significantly (P<0.05 and P<0.01 respectively) reduced fasting blood glucose level in normal rats as compared to glibenclamide (5 mg/kg). In oral glucose tolerance test, 500 mg/kg dose significantly reduced blood glucose level (P<0.05) at 2 h but 1 000 mg/kg dose significantly reduced blood glucose level at 2 h and 3 h (P<0.05 and P<0.01 respectively) whereas glibenclamide (5 mg/kg) significantly reduced glucose level at every hour after administration. Overall time effect is also considered extremely significant with F value=23.83 and P value=0.0001 in oral glucose tolerance test. Conclusion These findings suggest that the plant may be a potential source for the development of new oral hypoglycemic agent. PMID:25182949

  4. Neuroendocrine mechanism of onset of puberty. Sequential reduction in activity of inhibitory and facilitatory N-methyl-D-aspartate receptors.

    PubMed Central

    Bourguignon, J P; Gérard, A; Alvarez Gonzalez, M L; Franchimont, P

    1992-01-01

    In humans and in several animal species, puberty results from changes in pulsatile gonadotropin-releasing hormone (GnRH) secretion in the hypothalamus. In particular, the frequency of pulsatile GnRH secretion increases at the onset of puberty, as can be shown by using hypothalamic explants of male rats of 15 and 25 d. Previous observations from us and others suggested that the initiation of puberty could involve a facilitatory effect of excitatory amino acids mediated through N-methyl-D-aspartate (NMDA) receptors. We found that GnRH secretion could be activated through NMDA receptors only around the time of onset of puberty (25 d). The aim of this study was to clarify why this activation did not occur earlier (at 15 d) and could no longer be observed by the end of puberty (at 50 d). We studied GnRH secretion in the presence of MK-801, a noncompetitive antagonist of NMDA receptors or AP-5, a competitive antagonist. We showed that, in the hypothalamus of immature male rats (15 d), a highly potent inhibitory control of pulsatile GnRH secretion in vitro was mediated through NMDA receptors. These data were confirmed in vivo because administration of the antagonist MK-801 (0.001 mg/kg) to immature male rats resulted in early pubertal development. Onset of puberty (25 d) was characterized by the disappearance of that NMDA receptor-mediated inhibition, thus unmasking a facilitatory effect also mediated through NMDA receptors. During puberty, there was a reduction in activity of this facilitatory control which was no longer opposed by its inhibitory counterpart. We conclude that a sequential reduction in activity of inhibitory and facilitatory NMDA receptors provides a developmental basis for the neuroendocrine mechanism of onset of puberty. Images PMID:1430201

  5. The active zone protein family ELKS supports Ca2+ influx at nerve terminals of inhibitory hippocampal neurons.

    PubMed

    Liu, Changliang; Bickford, Lydia S; Held, Richard G; Nyitrai, Hajnalka; Südhof, Thomas C; Kaeser, Pascal S

    2014-09-10

    In a presynaptic nerve terminal, synaptic vesicle exocytosis is restricted to specialized sites called active zones. At these sites, neurotransmitter release is determined by the number of releasable vesicles and their probability of release. Proteins at the active zone set these parameters by controlling the presynaptic Ca(2+) signal, and through docking and priming of synaptic vesicles. Vertebrate ELKS proteins are enriched at presynaptic active zones, but their functions are not well understood. ELKS proteins are produced by two genes in vertebrates, and each gene contributes ∼50% to total brain ELKS. We generated knock-out mice for ELKS1 and found that its constitutive removal causes lethality. To bypass lethality, and to circumvent redundancy between ELKS1 and ELKS2 in synaptic transmission, we used a conditional genetic approach to remove both genes in cultured hippocampal neurons after synapses are established. Simultaneous removal of ELKS1 and ELKS2 resulted in a 50% decrease of neurotransmitter release at inhibitory synapses, paralleled by a reduction in release probability. Removal of ELKS did not affect synapse numbers or their electron microscopic appearance. Using Ca(2+) imaging, we found that loss of ELKS caused a 30% reduction in single action potential-triggered Ca(2+) influx in inhibitory nerve terminals, consistent with the deficits in synaptic transmission and release probability. Unlike deletion of the active zone proteins RIM, RIM-BP, or bruchpilot, ELKS removal did not lead to a measurable reduction in presynaptic Ca(2+) channel levels. Our results reveal that ELKS is required for normal Ca(2+) influx at nerve terminals of inhibitory hippocampal neurons.

  6. The Active Zone Protein Family ELKS Supports Ca2+ Influx at Nerve Terminals of Inhibitory Hippocampal Neurons

    PubMed Central

    Liu, Changliang; Bickford, Lydia S.; Held, Richard G.; Nyitrai, Hajnalka

    2014-01-01

    In a presynaptic nerve terminal, synaptic vesicle exocytosis is restricted to specialized sites called active zones. At these sites, neurotransmitter release is determined by the number of releasable vesicles and their probability of release. Proteins at the active zone set these parameters by controlling the presynaptic Ca2+ signal, and through docking and priming of synaptic vesicles. Vertebrate ELKS proteins are enriched at presynaptic active zones, but their functions are not well understood. ELKS proteins are produced by two genes in vertebrates, and each gene contributes ∼50% to total brain ELKS. We generated knock-out mice for ELKS1 and found that its constitutive removal causes lethality. To bypass lethality, and to circumvent redundancy between ELKS1 and ELKS2 in synaptic transmission, we used a conditional genetic approach to remove both genes in cultured hippocampal neurons after synapses are established. Simultaneous removal of ELKS1 and ELKS2 resulted in a 50% decrease of neurotransmitter release at inhibitory synapses, paralleled by a reduction in release probability. Removal of ELKS did not affect synapse numbers or their electron microscopic appearance. Using Ca2+ imaging, we found that loss of ELKS caused a 30% reduction in single action potential-triggered Ca2+ influx in inhibitory nerve terminals, consistent with the deficits in synaptic transmission and release probability. Unlike deletion of the active zone proteins RIM, RIM-BP, or bruchpilot, ELKS removal did not lead to a measurable reduction in presynaptic Ca2+ channel levels. Our results reveal that ELKS is required for normal Ca2+ influx at nerve terminals of inhibitory hippocampal neurons. PMID:25209271

  7. Virtual Screening and Optimization Yield Low-Nanomolar Inhibitors of the Tautomerase Activity of Plasmodium falciparum Macrophage Migration Inhibitory Factor

    PubMed Central

    Dahlgren, Markus K.; Garcia, Alvaro Baeza; Hare, Alissa A.; Tirado-Rives, Julian; Leng, Lin; Bucala, Richard; Jorgensen, William L.

    2012-01-01

    The Plasmodium falciparum ortholog of the human cytokine, macrophage migratory inhibitory factor (PfMIF), is produced by the parasite during malaria infection and modulates the host’s immune response. As for other MIF orthologs, PfMIF has tautomerase activity, whose inhibition may influence the cytokine activity. To identify small-molecule inhibitors of the tautomerase activity of PfMIF, virtual screening has been performed by docking 2.1 million compounds into the enzymatic site. Assaying of 17 compounds identified four as active. Substructure search for the most potent of these compounds, a 4-phenoxypyridine analogue, identified four additional compounds that were purchased and also shown to be active. Thirty-one additional analogues were then designed, synthesized, and assayed. Three were found to be potent PfMIF tautomerase inhibitors with Ki values of ca. 40 nM; they are also highly selective with Ki values of >100 μM for human MIF. PMID:23067344

  8. Effect of Different Commerical Agar Preparations on the Inhibitory Activities of Phenols

    PubMed Central

    Sands, J. G.; Bennett, E. O.

    1966-01-01

    The minimal inhibitory concentrations of 11 phenolic inhibitors were compared in five commercial agars and in nutrient broth. It was found that the brand of agar affected the end point obtained for a particular inhibitor, and that the degree of antagonism varied with each compound studied. The results indicate that there are at least two deleterious factors present in agar, one of which is water-soluble and one which is not. The major portion of the total antagonism was due to the water-soluble factor, which could be removed by washing the agar in warm distilled water prior to use in the test medium. PMID:5959856

  9. In vitro inhibitory effect on pancreatic lipase activity of subfractions from ethanol extracts of fermented Oats (Avena sativa L.) and synergistic effect of three phenolic acids.

    PubMed

    Cai, Shengbao; Wang, Ou; Wang, Mengqian; He, Jianfeng; Wang, Yong; Zhang, Di; Zhou, Feng; Ji, Baoping

    2012-07-25

    The purpose of the present work is to study the pancreatic lipase inhibitory effects of different subfractions (n-hexane, ethyl acetate (EA), n-butanol, and water) from ethanol extracts of nonfermented and fungi-fermented oats and to delineate the interactions of three primary phenolic acids in the EA subfractions. The EA subfraction showed the highest inhibitory effect on pancreatic lipase activity at 1.5 mg/mL compared to the other subfractions, regardless of whether the oats were fermented. Meanwhile, both of the EA subfractions of two fungi-fermented oats demonstrated more effective inhibitory activity than that of nonfermented oats. A positive correlation between the total phenolics content and inhibitory activity was found. The inhibitory ability of the EA subfraction from nonfermented or fermented oats also displayed a dose-dependent effect. The standards of caffeic, ferulic, and p-coumaric acids, mainly included in EA subfractions of fermented oats, also displayed a dose-dependent inhibitory effect. A synergistic effect of each binary combination of p-coumaric, ferulic, and caffeic acids was observed, especially at 150.0 μg/mL. Those results indicate that fungi-fermented oats have a more effective inhibitory ability on pancreatic lipase and polyphenols may be the most effective component and could be potentially used for dietary therapy of obesity.

  10. Characterization of Peptides from Capsicum annuum Hybrid Seeds with Inhibitory Activity Against α-Amylase, Serine Proteinases and Fungi.

    PubMed

    Vieira Bard, Gabriela C; Nascimento, Viviane V; Ribeiro, Suzanna F F; Rodrigues, Rosana; Perales, Jonas; Teixeira-Ferreira, André; Carvalho, André O; Fernandes, Katia Valevski S; Gomes, Valdirene M

    2015-04-01

    Over the last several years, the activity of antimicrobial peptides (AMPs), isolated from plant species, against different microorganisms has been demonstrated. More recently, some of these AMPs have been described as potent inhibitors of α-amylases and serine proteinases from insects and mammals. The aim of this work was to obtain AMPs from protein extracts of a hybrid Capsicum (Ikeda × UENF 1381) seeds and to evaluate their microbial and enzyme inhibitory activities. Initially, proteins were extracted from the Capsicum hybrid seeds in buffer (sodium phosphate pH 5.4,) and precipitated with ammonium sulfate (90% saturated). Extract of hybrid seeds was subjected to size exclusion chromatography, and three fractions were obtained: S1, S2 and S3. The amino acid sequence, obtained by mass spectrometry, of the 6 kDa peptide from the S3 fraction, named HyPep, showed 100% identity with PSI-1.2, a serine protease inhibitor isolated from C. annuum seeds, however the bifunctionality of this inhibitor against two enzymes is being shown for the first time in this work. The S3 fraction showed the highest antifungal activity, inhibiting all the yeast strains tested, and it also exhibited inhibitory activity against human salivary and Callosobruchus maculatus α-amylases as well as serine proteinases.

  11. In Vitro Screening of Medicinal Plants Used in Mexico as Antidiabetics with Glucosidase and Lipase Inhibitory Activities

    PubMed Central

    Ramírez, Guillermo; Zavala, Miguel; Pérez, Julia; Zamilpa, Alejandro

    2012-01-01

    This work shows the inhibitory effect on glucosidase and lipase enzymes of 23 medicinal plants described as traditional treatments for diabetes in several Mexican sources. Hydroalcoholic extracts of selected plants were evaluated at 1 mg/mL for glucosidase and 0.25 mg/mL for lipase inhibitory activities, respectively. Camellia sinensis, acarbose, and orlistat were used as positive controls. Dose-response curves were done with the most active species. Sixty percent of all tested extracts inhibited more than 25% of α-glucosidase activity. C. sinensis displayed an inhibition of 85% (IC50 = 299 μg/mL), while Ludwigia octovalvis and Iostephane heterophylla showed the highest inhibition (82.7 %, IC50 = 202 μg/mL and 60.6%, CI50 = 509 μg/mL, resp.). With respect to lipase activity, L. octovalvis and Tecoma stans were the most inhibiting treatments (31.4%, IC50 = 288 μg/mL; 27.2%, IC50 = 320 μg/mL), while C. sinensis displayed 45% inhibition (IC50 = 310 μg/mL). These results indicate that a high proportion of plants used in Mexico as treatment for diabetes displays significant inhibition of these digestive enzymes. PMID:23082084

  12. Antioxidant, α-glucosidase and xanthine oxidase inhibitory activity of bioactive compounds from maize (Zea mays L.).

    PubMed

    Nile, Shivraj H; Park, Se W

    2014-01-01

    Chemical investigations into maize (Zea mays L.) kernels yielded phenolic compounds, which were structurally established using chromatographic and spectroscopic methods. The isolated phenolic compounds from maize kernel were examined in vitro for their antioxidant abilities by DPPH (2,2-diphenyl-1-picryl hydrazine) radical, OH radical scavenging activity, and reducing ability, along with α-glucosidase and xanthine oxidase (XO) inhibition. The isolated maize phenolics revealed significant xanthine oxidase and α-glucosidase inhibitory activity to that of allopurinol and acarbose in vitro and in vivo, respectively. The kinetics study with xanthine oxidase revealed competitive type of inhibition by isolated maize vanillic acid (M2), ferulic acid (M5), 3'-methoxyhirsutrin (M7), and peonidin-3-glucoside (M10) as compared to control allopurinol. Overall, with few exceptions, all the phenolic compounds from maize kernel revealed significant biological activities with all parameters examined. Also, the phenolic compounds from maize were found to be more reactive toward DPPH radical and had considerable reducing ability and OH radical scavenging activity. These findings suggest that maize kernel phenolic compounds can be considered as potential antioxidant, α-glucosidase, and XO inhibitory agents those might be further explored for the design of lead antioxidant, antidiabetic and antigout drug candidates using in vivo trials. PMID:23957301

  13. Inhibitory effect of linalool-rich essential oil from Lippia alba on the peptidase and keratinase activities of dermatophytes.

    PubMed

    Costa, Danielle Cristina Machado; Vermelho, Alane Beatriz; Almeida, Catia Amancio; de Souza Dias, Edilma Paraguai; Cedrola, Sabrina Martins Lage; Arrigoni-Blank, Maria de Fátima; Blank, Arie Fitzgerald; Alviano, Celuta Sales; Alviano, Daniela Sales

    2014-02-01

    Abstract Lippia alba (Miller) N.E. Brown is an aromatic plant known locally as "Erva-cidreira-do-campo" that has great importance in Brazilian folk medicine. The aim of our study was to evaluate the antidermatophytic potential of linalool-rich essential oil (EO) from L. alba and analyze the ability of this EO to inhibit peptidase and keratinase activities, which are important virulence factors in dermatophytes. The minimum inhibitory concentrations (MICs) of L. alba EO were 39, 156 and 312 µg/mL against Trichophyton rubrum, Epidermophyton floccosum and Microsporum gypseum, respectively. To evaluate the influence of L. alba EO on the proteolytic and keratinolytic activities of these dermatophytes, specific inhibitory assays were performed. The results indicated that linalool-rich EO from L. alba inhibited the activity of proteases and keratinases secreted from dermatophytes, and this inhibition could be a possible mechanism of action against dermatophytes. Due to the effective antidermatophytic activity of L. alba EO, further experiments should be performed to explore the potential of this linalool-rich EO as an alternative antifungal therapy.

  14. B-Ring-modified and/or 5-demethylated nobiletin congeners: inhibitory activity against pro-MMP-9 production.

    PubMed

    Oshitari, Tetsuta; Okuyama, Yuji; Miyata, Yoshiki; Kosano, Hiroshi; Takahashi, Hideyo; Natsugari, Hideaki

    2011-12-01

    Three metabolites and 12 analogues of nobiletin (1) were synthesized. Whereas nobiletin derivatives 2-4 inhibited pro-MMP-9 production similarly in both PMA- and TNF-α-stimulated human lens epithelial cells, the 2'-hydroxylated analogue 5a exerted marked inhibitory effects (IC(50): 0.4 μM) on PMA-treated cells, which were 170-fold more potent than those on TNF-α-treated cells. This activity may be closely related to PKC-mediated transcriptional regulation of pro-MMP-9.

  15. A new hexacyclic triterpene acid from the roots of Euscaphis japonica and its inhibitory activity on triglyceride accumulation.

    PubMed

    Li, Yan-Ci; Tian, Ke; Sun, Li-Juan; Long, Hui; Li, Lu-Jun; Wu, Zheng-Zhi

    2016-03-01

    A new taraxerene-type hexacyclic triterpene acid named (12R,13S)-3-methoxy-12,13-cyclo-taraxerene-2,14-diene-1-one-28-oic acid (1), together with a known compound 3,7-dihydroxy-5-octanolide (2), was isolated from the roots of Euscaphis japonica. The structure of new compound 1 was elucidated on the basis of NMR, HR-ESIMS and X-ray diffraction analysis. It showed promising inhibitory activity on oleic acid induced triglyceride accumulation on HepG2 cells. PMID:26828452

  16. New hippolide derivatives with protein tyrosine phosphatase 1B inhibitory activity from the marine sponge Hippospongia lachne.

    PubMed

    Piao, Shu-Juan; Jiao, Wei-Hua; Yang, Fan; Yi, Yang-Hua; Di, Ying-Tong; Han, Bing-Nan; Lin, Hou-Wen

    2014-07-01

    Five new sesterterpenoids, compounds 1-5, have been isolated from the sponge Hippospongia lachne off Yongxing Island in the South China Sea. The structures of compounds 1-5 were elucidated through extensive spectroscopic analysis, including HRMS, 1D, and 2D NMR experiments. The stereochemistry, including absolute configurations of these compounds, was determined by spectroscopic, chemical, and computational methods. Compounds 1 and 5 showed moderate protein tyrosine phosphatase 1B (PTP1B) inhibitory activities with IC50 values of 5.2 μM and 8.7 μM, respectively, more potent than previously reported hippolides.

  17. Incorporation of Bulky and Cationic Cyclam-Triazole Moieties into Marimastat Can Generate Potent MMP Inhibitory Activity without Inducing Cytotoxicity

    PubMed Central

    Yu, Mingfeng; Lim, Ngee H; Ellis, Samantha; Nagase, Hideaki; Triccas, James A; Rutledge, Peter J; Todd, Matthew H

    2013-01-01

    The synthesis and matrix metalloproteinase (MMP) inhibitory activity of a cyclam–marimastat conjugate and its metal complexes are described. The conjugate, synthesized with a copper(I)-catalyzed Huisgen 1,3-dipolar cycloaddition (“click” reaction), contains two zinc-binding groups (ZBGs). The metal complexation behavior with copper(II) and zinc(II) was investigated using UV/Vis spectrophotometry and 1H NMR spectroscopy, respectively, demonstrating that the first equivalent of the metal ion was chelated by the cyclam-triazole moiety rather than the hydroxamic acid site. Thus, the corresponding mononuclear metal–cyclam complexes were successfully prepared with one equivalent of the metal salt. Both the cyclam–marimastat conjugate and its metal complexes exhibited slightly reduced potency against MMP-1, but essentially identical inhibitory activity against MMP-3. The conjugate and its metal complexes displayed little or no cytotoxicity, further supporting their potential suitability for imaging MMP localization and activity. To the best of our knowledge, this is the first report that describes the incorporation of metal complexes into an MMP inhibitor without influencing the preexisting ZBG, and the first report of the evaluation of structures containing more than one ZBG as MMP inhibitors. PMID:24551546

  18. Hyaluronidase Inhibitory Activity of Pentacylic Triterpenoids from Prismatomeris tetrandra (Roxb.) K. Schum: Isolation, Synthesis and QSAR Study

    PubMed Central

    Abdullah, Nor Hayati; Thomas, Noel Francis; Sivasothy, Yasodha; Lee, Vannajan Sanghiran; Liew, Sook Yee; Noorbatcha, Ibrahim Ali; Awang, Khalijah

    2016-01-01

    The mammalian hyaluronidase degrades hyaluronic acid by the cleavage of the β-1,4-glycosidic bond furnishing a tetrasaccharide molecule as the main product which is a highly angiogenic and potent inducer of inflammatory cytokines. Ursolic acid 1, isolated from Prismatomeris tetrandra, was identified as having the potential to develop inhibitors of hyaluronidase. A series of ursolic acid analogues were either synthesized via structure modification of ursolic acid 1 or commercially obtained. The evaluation of the inhibitory activity of these compounds on the hyaluronidase enzyme was conducted. Several structural, topological and quantum chemical descriptors for these compounds were calculated using semi empirical quantum chemical methods. A quantitative structure activity relationship study (QSAR) was performed to correlate these descriptors with the hyaluronidase inhibitory activity. The statistical characteristics provided by the best multi linear model (BML) (R2 = 0.9717, R2cv = 0.9506) indicated satisfactory stability and predictive ability of the developed model. The in silico molecular docking study which was used to determine the binding interactions revealed that the ursolic acid analog 22 had a strong affinity towards human hyaluronidase. PMID:26907251

  19. Design and synthesis of conformationally constrained analogues of cis-cinnamic acid and evaluation of their plant growth inhibitory activity.

    PubMed

    Nishikawa, Keisuke; Fukuda, Hiroshi; Abe, Masato; Nakanishi, Kazunari; Tazawa, Yuta; Yamaguchi, Chihiro; Hiradate, Syuntaro; Fujii, Yoshiharu; Okuda, Katsuhiro; Shindo, Mitsuru

    2013-12-01

    1-O-cis-Cinnamoyl-β-D-glucopyranose is known to be one of the most potent allelochemical candidates and was isolated from Spiraea thunbergii Sieb by Hiradate et al. (2004), who suggested that it derived its strong inhibitory activity from cis-cinnamic acid, which is crucial for phytotoxicity. In this study, key structural features and substituent effects of cis-cinnamic acid (cis-CA) on lettuce root growth inhibition was investigated. These structure-activity relationship studies indicated the importance of the spatial relationship of the aromatic ring and carboxylic acid moieties. In this context, conformationally constrained cis-CA analogues, in which the aromatic ring and cis-olefin were connected by a carbon bridge, were designed, synthesized, and evaluated as plant growth inhibitors. The results of the present study demonstrated that the inhibitory activities of the five-membered and six-membered bridged compounds were enhanced, up to 0.27 μM, and were ten times higher than cis-CA, while the potency of the other compounds was reduced.

  20. Quantitative Determination of Alkaloids in Lotus Flower (Flower Buds of Nelumbo nucifera) and Their Melanogenesis Inhibitory Activity.

    PubMed

    Morikawa, Toshio; Kitagawa, Niichiro; Tanabe, Genzoh; Ninomiya, Kiyofumi; Okugawa, Shuhei; Motai, Chiaki; Kamei, Iyori; Yoshikawa, Masayuki; Lee, I-Jung; Muraoka, Osamu

    2016-01-01

    A quantitative analytical method for five aporphine alkaloids, nuciferine (1), nornuciferine (2), N-methylasimilobine (3), asimilobine (4), and pronuciferine (5), and five benzylisoquinoline alkaloids, armepavine (6), norarmepavine (7), N-methylcoclaurine (8), coclaurine (9), and norjuziphine (10), identified as the constituents responsible for the melanogenesis inhibitory activity of the extracts of lotus flowers (the flower buds of Nelumbo nucifera), has been developed using liquid chromatography-mass spectrometry. The optimum conditions for separation and detection of these 10 alkaloids were achieved on a πNAP column, a reversed-phase column with naphthylethyl group-bonded silica packing material, with CH₃CN-0.2% aqueous acetic acid as the mobile phase and using mass spectrometry equipped with a positive-mode electrospray ionization source. According to the protocol established, distributions of these 10 alkaloids in the petal, receptacle, and stamen parts, which were separated from the whole flower, were examined. As expected, excellent correlations were observed between the total alkaloid content and melanogenesis inhibitory activity. Among the active alkaloids, nornuciferine (2) was found to give a carbamate salt (2'') via formation of an unstable carbamic acid (2') by absorption of carbon dioxide from the air. PMID:27447599

  1. In vitro inhibitory effects of Moringa oleifera leaf extract and its major components on chemiluminescence and chemotactic activity of phagocytes.

    PubMed

    Vongsak, Boonyadist; Gritsanapan, Wandee; Wongkrajang, Yuvadee; Jantan, Ibrahim

    2013-11-01

    The ethanol extract of Moringa oleifera Lam. leaves and its major constituents, crypto-chlorogenic acid, quercetin 3-O-glucoside and kaempferol 3-O-glucoside, were investigated on the respiratory burst of human whole blood and isolated human polymorphonuclear leukocytes (PMNs) using a luminol-based chemiluminescence assay. The chemotactic migration of PMNs was also investigated using the Boyden chamber technique. The ethanol extract demonstrated inhibitory activities on the oxidative burst and the chemotactic migration of PMNs. Quercetin 3-O-glucoside, crypto-chlorogenic acid, and kaempferol 3-O-glucoside, isolated from the extract, expressed relatively strong inhibitory activity on the oxidative burst of PMNs with IC50 values of 4.1, 6.7 and 7.0 microM, respectively, comparable with that of aspirin. They also demonstrated strong inhibition of chemotatic migration of PMNs with IC50 values of 9.5, 15.9 and 18.2 microM, respectively. The results suggest that M. oleifera leaves could modulate the immune response of human phagocytes, linking to its ethnopharmacological use as an anti-inflammatory agent. The immunomodulating activity of the plant was mainly due to its major components. PMID:24427941

  2. Antioxidant capacity and angiotensin I converting enzyme inhibitory activity of a melon concentrate rich in superoxide dismutase.

    PubMed

    Carillon, Julie; Del Rio, Daniele; Teissèdre, Pierre-Louis; Cristol, Jean-Paul; Lacan, Dominique; Rouanet, Jean-Max

    2012-12-01

    Antioxidant capacity and angiotensin 1-converting enzyme (ACE) inhibitory activity of a melon concentrate rich in superoxide dismutase (SOD-MC) were investigated in vitro. The total antioxidant capacity (TAC) was measured by the Trolox equivalent antioxidant capacity assay (TEAC), the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assay, and the ferric reducing antioxidant power assay (FRAP). The ability of the extract to scavenge three specific reactive oxygen species (superoxide radical anion (O(2)(-)), hydroxyl radical (HO()) and hydrogen peroxide (H(2)O(2))) was also investigated in order to better evaluate its antioxidant properties. Even if the measures of TAC were relatively low, results clearly established an antioxidant potential of SOD-MC that exhibited the highest radical-scavenging activity towards O(2)(-), with a IC(50) 12-fold lower than that of H(2)O(2) or HO(). This lets hypothesis that the antioxidant potential of SOD-MC could be mainly due to its high level of SOD. Moreover, for the first time, an ACE inhibitory activity of SOD-MC (IC(50)=2.4±0.1mg/mL) was demonstrated, showing that its use as a functional food ingredient with potential preventive benefits in the context of hypertension may have important public health implications and should be carefully considered.

  3. alpha-Amylase inhibitory activity of some Malaysian plants used to treat diabetes; with particular reference to Phyllanthus amarus.

    PubMed

    Ali, Hasenah; Houghton, P J; Soumyanath, Amala

    2006-10-11

    Extracts of six selected Malaysian plants with a reputation of usefulness in treating diabetes were examined for alpha-amylase inhibition using an in vitro model. Inhibitory activity studied by two different protocols (with and without pre-incubation) showed that Phyllanthus amarus hexane extract had alpha-amylase inhibitory properties. Hexane and dichloromethane extracts of Anacardium occidentale, Lagerstroemia speciosa, Averrhoa bilimbiPithecellobium jiringa and Parkia speciosa were not active when tested without pre-incubation. Extraction and fractionation of Phyllanthus amarus hexane extract led to the isolation of dotriacontanyl docosanoate, triacontanol and a mixture of oleanolic acid and ursolic acid. Dotriacontanyl docosanoate and the mixture of oleanolic acid and ursolic acid are reported from this plant species for the first time. All compounds were tested in the alpha-amylase inhibition assay and the results revealed that the oleanolic acid and ursolic acid (2:1) mixture was a potent alpha-amylase inhibitor with IC(50)=2.01 microg/ml (4.41 microM) and that it contributes significantly to the alpha-amylase inhibition activity of the extract. Three pure pentacyclic triterpenoids, oleanolic acid, ursolic acid and lupeol were shown to inhibit alpha-amylase.

  4. Alkaloid metabolite profiles by GC/MS and acetylcholinesterase inhibitory activities with binding-mode predictions of five Amaryllidaceae plants.

    PubMed

    Cortes, Natalie; Alvarez, Rafael; Osorio, Edison H; Alzate, Fernando; Berkov, Strahil; Osorio, Edison

    2015-01-01

    Acetylcholinesterase (AChE) enzymatic inhibition is an important target for the management of Alzheimer disease (AD) and AChE inhibitors are the mainstay drugs for its treatment. In order to discover new sources of potent AChE inhibitors, a combined strategy is presented based on AChE-inhibitory activity and chemical profiles by GC/MS, together with in silico studies. The combined strategy was applied on alkaloid extracts of five Amaryllidaceae species that grow in Colombia. Fifty-seven alkaloids were detected using GC/MS, and 21 of them were identified by comparing their mass-spectral fragmentation patterns with standard reference spectra in commercial and private library databases. The alkaloid extracts of Zephyranthes carinata exhibited a high level of inhibitory activity (IC50 = 5.97 ± 0.24 μg/mL). Molecular modeling, which was performed using the structures of some of the alkaloids present in this extract and the three-dimensional crystal structures of AChE derived from Torpedo californica, disclosed their binding configuration in the active site of this AChE. The results suggested that the alkaloids 3-epimacronine and lycoramine might be of interest for AChE inhibition. Although the galanthamine group is known for its potential utility in treating AD, the tazettine-type alkaloids should be evaluated to find more selective compounds of potential benefit for AD. PMID:25305596

  5. Lack of inhibitory effects of several fluoroquinolones on cytochrome P-450 3A activities at clinical dosage in dogs.

    PubMed

    Regmi, N L; Abd El-Aty, A M; Kubota, R; Shah, S S; Shimoda, M

    2007-02-01

    Inhibitory effects of several fluoroquinolones (FQs) on liver CYP3A activities were examined by in vitro and in vivo tests in dogs. Midazolam (MDZ) hydroxylation rate was used to determine the CYP3A activities in liver microsomes. Enrofloxacin (EFX), ofloxacin (OFX) orbifloxacin (OBFX) and ciprofloxacin (CFX) were tested. None of the FQs changed Vmax, Km or intrinsic clearance (Vmax/Km) of MDZ. For in vivo test, we examined the effects of oral administration of EFX and OFX on the pharmacokinetics of quinidine (QN), a CYP3A substrate. EFX or OFX (10 mg/kg) was administered once a day for 3 days. QN (2 mg/kg) was intravenously injected at 2 h after the final dose of FQs administration. The same dose of QN was intravenously injected 3 weeks before the start of FQs administration for control. Neither EFX nor OFX changed the pharmacokinetic parameters of QN. These in vitro and in vivo consisted results suggest that these FQs lack the inhibitory effects on CYP3A activities in dogs. Hence, given these results, the risk of drug-drug interaction is unlikely to occur between FQs and CYP3A substrates in clinical situation in dogs.

  6. In vitro inhibitory effects of Moringa oleifera leaf extract and its major components on chemiluminescence and chemotactic activity of phagocytes.

    PubMed

    Vongsak, Boonyadist; Gritsanapan, Wandee; Wongkrajang, Yuvadee; Jantan, Ibrahim

    2013-11-01

    The ethanol extract of Moringa oleifera Lam. leaves and its major constituents, crypto-chlorogenic acid, quercetin 3-O-glucoside and kaempferol 3-O-glucoside, were investigated on the respiratory burst of human whole blood and isolated human polymorphonuclear leukocytes (PMNs) using a luminol-based chemiluminescence assay. The chemotactic migration of PMNs was also investigated using the Boyden chamber technique. The ethanol extract demonstrated inhibitory activities on the oxidative burst and the chemotactic migration of PMNs. Quercetin 3-O-glucoside, crypto-chlorogenic acid, and kaempferol 3-O-glucoside, isolated from the extract, expressed relatively strong inhibitory activity on the oxidative burst of PMNs with IC50 values of 4.1, 6.7 and 7.0 microM, respectively, comparable with that of aspirin. They also demonstrated strong inhibition of chemotatic migration of PMNs with IC50 values of 9.5, 15.9 and 18.2 microM, respectively. The results suggest that M. oleifera leaves could modulate the immune response of human phagocytes, linking to its ethnopharmacological use as an anti-inflammatory agent. The immunomodulating activity of the plant was mainly due to its major components.

  7. Angiotensin-converting enzyme inhibitory activity and antioxidant properties of Nepeta crassifolia Boiss & Buhse and Nepeta binaludensis Jamzad.

    PubMed

    Tundis, Rosa; Nadjafi, Farsad; Menichini, Francesco

    2013-04-01

    This article reports phytochemical and biological studies on Nepeta binaludensis and Nepeta crassifolia. Both species were investigated for their angiotensin-converting enzyme (ACE) inhibitory activity and antioxidant properties through three in vitro models [2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazolin