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PubMed2002

Biological monitoring of environment exposure to safrole and the Taiwanese betel quid chewing.

A rapid and sensitive biological monitoring (BM) method for assessing exposure to the environmental carcinogen safrole has been developed. The method is an isocratic high-performance liquid chromatographic (HPLC) analysis of urinary dihydroxychavicol (DHAB) and eugenol, the urinary metabolites of safrole. Good linearity, precision, and accuracy were demonstrated. A recovery of 98.8 +/- 5.4% (SD, n = 3) was found for DHAB and 84.1 +/- 3.4% (n = 3) for eugenol. The quantitation limits of the method were 8 ng for DHAB and 10 ng for eugenol. The validity of the method was demonstrated by a linear dose-response relationship observed in rats given oral doses of safrole at 30, 75, and 150 mg/kg body weight. The method was also used to monitor the environmental exposure to the Taiwanese betel quid (TBQ) chewing, because TBQ used in Taiwan not only contains areca (betel) nut, slaked lime, and catechu but also Piper betle inflorescence or its leaves. Both of the latter have a high content of safrole. The feasibility of the method to monitor TBQ chewing was demonstrated by an analysis of 153 spot human urine samples. The results showed that the p value of the nonparametric group comparison was < 0.001 for DHAB and 0.832 for eugenol. The TBQ chewers also exhibited a significantly higher rate of urinary DHAB (but not eugenol) than the nonchewers with an odd ratio of 3.47 (95% CI, 1.61-7.51). However, when only the eugenol-positive subjects were taken into analysis, the ratio rose to 24.38 (95% CI, 3.00-197.90).

Administration, Oral↗
PubMed2006

Induction of plant defense enzymes and phenolics by treatment with plant growth-promoting rhizobacteria Serratia marcescens NBRI1213.

In greenhouse experiments, plant growth-promoting rhizobacteria (PGPR) Serratia marcescens NBRI1213 was evaluated for plant growth promotion and biologic control of foot and root rot of betelvine caused by Phytophthora nicotianae. Bacterization of betelvine (Piper betle L.) cuttings with S. marcescens NBRI1213 induced phenylalanine ammonia-lyase, peroxidase, and polyphenoloxidase activities in leaf and root. Qualitative and quantitative estimation of phenolic compounds was done through high-performance liquid chromatography (HPLC) in leaf and root of betelvine after treatment with S. marcescens NBRI1213 and infection by P. nicotianae. Major phenolics detected were gallic, protocatechuic, chlorogenic, caffeic, ferulic, and ellagic acids by comparison of their retention time with standards through HPLC. In all of the treated plants, synthesis of phenolic compounds was enhanced compared with control. Maximum accumulation of phenolics was increased in S. marcescens NBRI1213-treated plants infected with P. nicotianae. In a greenhouse test, bacterization using S. marcescens NBRI1213 decreased the number of diseased plants compared with nonbacterized controls. There were significant growth increases in shoot length, shoot dry weight, root length, and root dry weight, averaging 81%, 68%, 152%, and 290%, respectively, greater than untreated controls. This is the first report of PGPR-mediated induction of phenolics for biologic control and their probable role in protecting betelvine against P. nicotianae, an important soil-borne phytopathogenic fungus.

Hydroxybenzoates↗
PubMed2006

Ultrastructural alterations induced by the neolignan dihydrobenzofuranic eupomatenoid-5 on epimastigote and amastigote forms of Trypanosoma cruzi.

Eupomatenoid-5, a compound isolated from leaves of Piper regnellii var. pallescens, showed antiprotozoal activity against the epimastigote proliferative stages and intracellular amastigote forms of Trypanosoma cruzi Y strain. Eupomatenoid-5, at 7.0 microg/ml (50% growth inhibition concentration) produced morphological changes in epimastigote forms of the parasite, such as intense cytoplasmic vacuolization, mitochondrial swelling, kinetoplast alteration, presence of myelin-like figures, and mitochondrial damage, as observed by transmission electron microscopy. In amastigote forms in LLCMK(2) cells, at 7.0-microg/ml concentration, the compound induced a decrease in the number of cells with internalized parasites and in the number of internalized parasites per LLCMK(2) cell, compared with untreated cells. Furthermore, intense cytoplasmic vacuolization and autophagic vacuoles were observed in T. cruzi intracellular amastigotes after 72 h of incubation. Scanning electron microscopy confirmed the alterations in the shape of the parasites.

Animals↗
PubMed2005

The influence of a neotropical herbivore (Lamponius portoricensis) on nutrient cycling and soil processes.

The role of phytophagous insects in ecosystem nutrient cycling remains poorly understood. By altering the flow of litterfall nutrients from the canopy to the forest floor, herbivores may influence key ecosystem processes. We manipulated levels of herbivory in a lower montane tropical rainforest of Puerto Rico using the common herbivore, Lamponius portoricensis (Phasmatidea), on a prevalent understory plant, Piper glabrescens (Piperaceae), and measured the effects on nutrient input to the forest floor and on rates of litter decomposition. Four treatment levels of herbivory generated a full range of leaf area removal, from plants experiencing no herbivory to plants that were completely defoliated (>4,000 cm(2) leaf area removed during the 76-day study duration). A significant (P<0.05) positive regression was found between all measures of herbivory (total leaf area removed, greenfall production, and frass-related inputs) and the concentration of NO (3) (-) in ion exchange resin bags located in the litter layer. No significant relationship was found between any of the herbivory components and resin bag concentrations of NH (4) (+) or PO (4) (-) . Rates of litter decay were significantly affected by frass-related herbivore inputs. A marginally significant negative relationship was also found between the litter mass remaining at 47 days and total leaf area removed. This study demonstrated a modest, but direct relationship between herbivory and both litter decomposition and NO (3) (-) transfer to the forest floor. These results suggest that insect herbivores can influence forest floor nutrient dynamics and thus merit further consideration in discussions on ecosystem nutrient dynamics.

Animals↗
PubMed2006

Postnatal development and reproductive performance of F1 progeny exposed in utero to an ayurvedic contraceptive: Pippaliyadi yoga.

Pippaliyadi yoga or pippaliyadi vati is an ayurvedic contraceptive used in India since ancient times. It is a combination of powdered fruit berries of Embelia ribes Burm.f. (Myrsinaceae), Piper longum L. (Piperaceae) and borax in equal proportion. Though the contraceptive potential is known since ancient times, no systematic developmental toxicity studies have been carried out. The present study was carried out to evaluate the postnatal developmental toxicity and the reproductive performance of the progeny exposed in utero to pippaliyadi. Pippaliyadi yoga was obtained from National Institute for Pharmaceutical Education and Research (NIPER), India and the developmental toxicity was studied by administering three doses, viz. 140, 300 and 700 mg/(kg day) to gravid females from day 6 to day 16 of gestation. Pippaliyadi did not have any adverse developmental effects with low doses, however, with the five times higher dose, a decrease in body weight of the pups was observed. The reproductive performance of the progeny born to mothers treated with pippaliyadi was not significantly affected. The present study suggests that in utero exposure to pippaliyadi does not have any adverse effect on the postnatal development and reproductive performance of the F(1) progeny.

Animals↗
PubMed2006

Piplartine induces inhibition of leukemia cell proliferation triggering both apoptosis and necrosis pathways.

Piplartine {5,6-dihydro-1-[1-oxo-3-(3,4,5-trimethoxyphenyl)-2-propenyl]-2(1H)pyridinone} is an alkaloid/amide component of Piper species. The purpose of the present study was to examine the antiproliferative effects of piplartine on human leukemia cell lines HL-60, K562, Jukart, and Molt-4 using the trypan blue exclusion method, as well as the effect of piplartine on DNA synthesis. The viability of all human leukemia cell lines were not affected by piplartine after 6 h, 9 h, and 12 h exposure, whereas a steady decline was seen after an exposure time of 24 h. The antiproliferative activity of piplartine seemed to be related to the inhibition of DNA synthesis, as revealed by the reduction of 5-bromo-2'-deoxyuridine (BrdU) incorporation after 24h of incubation. Piplartine-mediated reduction in cell number was associated with an increasing number of dead cells at a concentration of 10 microg/ml. These findings were corroborated by morphologic analysis. However, at the lowest concentration (2.5 microg/ml), piplartine-treated cells exhibited typical apoptotic morphological changes. The increase in caspase-3 activity was also observed in lysates of piplartine-treated cells (2.5 microg/ml). Our findings suggest that piplartine can suppress leukemia growth and reduce cell survival, triggering both apoptosis and/or necrosis, depending on the concentration used.

Antineoplastic Agents, Phytogenic↗
PubMed2004

Hydroxychavicol modulates benzo[a]pyrene-induced genotoxicity through induction of dihydrodiol dehydrogenase.

Areca quid (AQ) chewing and smoking have synergistic potential in the development of oral squamous cell carcinoma (OSCC). In Taiwan, fresh Piper betle inflorescence is uniquely added to AQ, and hydroxychavicol (HC) is the major phenolic component of P. betle inflorescence. This study investigated whether HC modulates cigarette carcinogen benzo[a]pyrene (B[a]P)-mediated toxic effects. Pretreatment of HC and followed by B[a]P challenge resulted in higher cytotoxicity and HPRT gene mutation frequency (P < 0.05). However, this treatment protocol resulted in decreased bulky B[a]P-DNA adduct levels as demonstrated by 32P-postlabeling technique (P < 0.05). Western blotting analysis indicated that HC pretreatment induced the expression of cyclooxygenase-2 (COX-2) and dihydrodiol dehydrogenase (DDH). COX-2 is know to participate in the B[a]P-DNA adduct formation, while DDH has been shown to divert B[a]P-diol to B[a]P-7,8-quinone and the generation of reactive oxygen species (ROS). Using flow cytometry, this study demonstrated the increased production of 8-oxoguanine (P < 0.001). Overall, the results suggest that HC-induced DDH is more important than site-by-site up-regulation of COX-2 in B[a]P-induced cytotoxicity and HPRT gene mutation. Furthermore, DDH-mediated oxidative DNA damage and not B[a]P-DNA adduct formation may be involved in the HC and B[a]P-induced toxic effects.

Areca↗
PubMed1997

The C-terminus of yeast plasma membrane H+-ATPase is essential for the regulation of this enzyme by heat shock protein Hsp30, but not for stress activation.

Several stresses cause additional activation to the glucose-stimulated plasma membrane H+-ATPase activity of yeast, but it is not clear how this is achieved. We recently reported that cells lacking the integral plasma membrane heat shock protein Hsp30 display enhanced increases in plasma membrane H+-ATPase activity with either heat shock or weak organic acid stress (Piper, P.W., Ortiz-Calderon, C., Holyoak, C., Coote, P. and Cole, M. (1997) Cell Stress and Chaperones 2, 12-24), indicating that the stress induction of Hsp30 acts to reduce stress stimulation of the H+-ATPase. In this study it is shown that Hsp30 acts to reduce the Vmax of H+-ATPase in heat shocked cells. Its action is lost with deletion of the C-terminal 11 amino acids of the H+-ATPase, a deletion that does not abolish the stress stimulation of this enzyme. Mutation of the Thr-912 residue within the C-terminal domain of H+-ATPase, a potential site of phosphorylation by the Ca2+-calmodulin-dependent protein kinase, also abolishes any effect of Hsp30. Hsp30 may therefore be acting on a Thr-912 phosphorylated form of the H+-ATPase.

Amino Acid Substitution↗
PubMed1998

Lactate dehydrogenase and the diagnosis of malaria.

Over the past five years, several methods have been developed that exploit the differences between Plasmodium lactate dehydrogenase (pLDH) and the human LDH isoforms for the purposes of measuring pLDH in blood and in in vitro cultures. These methods have been incorporated into an easy screening method for the identification and quantitation of parasite growth in in vitro cultures using a Malstattrade mark reagent. In addition, another quantitative microplate method, the immunocapture pLDH (IcpLDH) assay, has been developed that utilizes monoclonal antibodies (mAbs) to capture the pLDH and then to measure the captured enzyme by its ability to reduce 3 acetyl pyridine adenine dinucleotide (APAD). In addition, a rapid immunochromatographic method, the OptiMAL® assay, has been formatted to capture pLDH as an antigen, and then to signal the presence of this captured antigen (enzyme) with a colloid conjugated antibody. The microplate IcpLDH assay, and the dipstick OptiMAL® assays, are both being used for the diagnosis and monitoring of malaria infections, as described here by Michael Makler, Rob Piper and Wil Milhous.

Journal Article↗
PubMed2003

Antimutagenic properties of bell and black peppers.

The wing Somatic Mutation And Recombination Test (SMART) in Drosophila melanogaster was used to study the modulating action of bell pepper (Capsicum annuum) and black pepper (Piper nigrum) in combination with the alkylating agent methyl methanesulfonate (MMS) and the promutagen agent ethyl carbamate (EC). Larvae trans-heterozygous for the third chromosome recessive markers multiple wing hairs (mwh) and flare-3 [flr(3)] were fed genotoxins alone or in combination with each of the two spices. Genetic changes induced in somatic cells of the wing's imaginal discs lead to the formation of mutant clones on the wing blade. Our results showed that bell pepper was effective in reducing the mutational events induced by EC and MMS and black pepper was only effective against EC. Pretreatment of 2-day-old larvae with the spices for 24 h followed by a treatment with EC and MMS was only effective in reducing mutations induced by EC. Suppression of metabolic activation or interaction with the active groups of mutagens could be mechanisms by which the spices exert their antimutagenic action.

Animals↗
PubMed2002

Effect of some pulverised plant materials on the developmental stages of fish beetle, Dermestes maculatus Degeer in smoked catfish (Clarias gariepinus) during storage.

The effectiveness of pulverised plant materials; Tithonium diversifolia, Afromomum melegueta, Nicotiana tabacum, Monodora myristica and Piper guineense as ovicidal, larvicidal and adult deterents of fish beetle (Dermestes maculatus) in smoked catfish (Clarias gariepinus) during storage were evaluated. Leaves of T. diversifolia, N. tabacum and seeds of A. melegueta, M. myristica and P. guineese were dried and pulverised into powder. Adults and larvae of third generation (F3) of D. maculatus were introduced into Kilner jars containing disinfested fish samples. Pulverised plant materials were applied to the surface of the fish samples at 10% (w/w) and monitored for 40 days, while egg hatchability of the insects was monitored for seven days. The result showed that all the plant materials had varying degree of insecticidal activities. Pulverised powder of P. guineense and A. melegueta were the most effective and significantly (P < 0.05) inhibited egg hatchability and adult emergence of D. maculatus in smoked catfish. N. tabacum gave the lowest insecticidal effect on adults, larvae and eggs of D. maculatus. However, the larvae of D. maculatus were not significantly (P > 0.05) affected by the plant materials. The percentage weight loss in fish treated with P. guineense and A. melegueta were minimal compared with the untreated fish sample. The result of this study showed that pulverised plant materials obtained from P. guineense and A. melegueta could be used to deter egg hatchability and adult emergence of D. maculatus in smoked catfish during storage. This could also reduce percentage losses due to insect infestation on smoked fish during storage.

Animals↗
PubMed2002

CYP3A4 inhibitory activity of new bisalkaloids, dipiperamides D and E, and cognates from white pepper.

Two new bisalkaloids, dipiperamides D and E, were isolated as inhibitors of a drug metabolizing enzyme cytochrome P450 (CYP) 3A4 from the white pepper, Piper nigrum. Their structures were elucidated by spectroscopic methods. Dipiperamides D and E showed potent CYP3A4 inhibition with IC(50) values of 0.79 and 0.12 microM, respectively, and other metabolites from the pepper were moderately active or inactive.

Alkaloids↗
PubMed2003

The alliance as mediator of expectancy effects in short-term individual therapy.

The authors investigated the hypothesis that the therapeutic alliance mediates the relationship between pretherapy expectancy of improvement and psychotherapy outcome. Data were drawn from a comparative trial of 2 forms of short-term, time-limited individual psychotherapy (W. E. Piper, A. S. Joyce, M. McCallum, & H. F. Azim, 1998). Measures of expectancy and outcome were based on an individualized assessment of target objectives; outcome was considered from 3 perspectives (patient, independent assessor, therapist). Using the R. M. Baron and D. A. Kenny (1986) procedure, the authors found evidence in support of the hypothesized mediation effect. The effect was evident when the alliance was rated from the perspective of either patient or therapist, and it accounted for one third of the direct impact of expectancy on outcome. Clinical implications and limitations of the study are discussed.

Adult↗
PubMed2003

Antioxidant activity of piperlactam S: prevention of copper-induced LDL peroxidation and amelioration of free radical-induced oxidative stress of endothelial cells.

The protective effects of piperlactam S, an alkaloid isolated from Piper kadsura (Choisy) Ohwi, on lipid peroxidation and free radical-mediated cell injuries were investigated. Piperlactam S (1 to 20 microM) concentration-dependently prevented the copper-catalyzed oxidative modification of human low-density lipoproteins (LDL) measured through (i) the lag period, (ii) the slope of the propagation phase, (iii) the total amount of conjugated dienes formed, and (iv) the electrophoretic mobility of LDL. Fe2+-induced oxidative modification of cell membrane was also significantly attenuated by piperlactam S as measured by thiobarbituric acid-reactive substances (TBARS). Furthermore, piperlactam S effectively minimized the loss of cell viability induced by Fenton's reagent (H2O2/FeSO4) in cultured endothelial cells and significantly reversed H2O2/FeSO4-induced impairment of endothelium-dependent relaxation to acetylcholine in rat aorta. Since the oxidative modification of LDL plays an important role in the genesis of atherosclerosis, piperlactam S may help to reduce the risk of atherosclerosis, not only by protecting LDL and membrane lipids from oxidative modification but also by reducing free radical-induced endothelial injury and/or dysfunction.

Animals↗
PubMed2003

Anti-inflammatory properties of piperlactam S: modulation of complement 5a-induced chemotaxis and inflammatory cytokines production in macrophages.

Macrophages infiltrate tissues in response to chemoattractants including complement 5a (C5a). Infiltrating macrophages clear microorganisms but also can cause tissue damage. We hypothesized that prevention of macrophages from excessive recruitment into infected sites may underlie the anti-inflammatory effects of piperlactam S, an alkaloid isolated from Piper kadsura (Choisy) Ohwi. To test this hypothesis, chemotactic migration of RAW264.7 macrophages was induced by C5a and the effects of piperlactam S were studied. The results showed that piperlactam S (1-30 microM) concentration-dependently suppressed C5a-induced migration across a fibrinogen-coated barrier with an IC50 of 4.5 +/- 0.3 microM. At 30 microM, piperlactam S inhibited chemotaxis by more than 95 % and also decreased phagocytosis by 25 % without reducing macrophage viability and adherent capacity. Furthermore, piperlactam S treated cells adhered but failed to spread and elongate as in control cells. Finally, piperlactam S inhibited the C5a-stimulated release of tumor necrosis factor-alpha and interleukin-1beta. We conclude that retardation of macrophage recruitment by interfering with the migration process and suppression of cytokines production might underlie the potential usefulness of piperlactam S as an anti-inflammatory agent.

Animals↗
PubMed2003

Piperine lowers the serum concentrations of thyroid hormones, glucose and hepatic 5'D activity in adult male mice.

Piperine, the main alkaloid of Piper nigrum fruits, was evaluated for its thyroid hormone and glucose regulatory efficacy in adult male Swiss albino mice. Its daily oral administration (2.50 mg/kg) for 15 days lowered the serum levels of both the thyroid hormones, thyroxin (T (4)) and triiodothyronine (T (3)) as well as glucose concentrations with a concomitant decrease in hepatic 5'D enzyme and glucose-6-phospatase (G-6-Pase) activity. However, no significant alterations were observed in animals treated with 0.25 mg/kg of piperine in any of the activities studied except an inhibition in serum T (3) concentration. The decrease in T (4), T (3) concentrations and in G-6-Pase were comparable to that of a standard antithyroid drug, Proylthiouracil (PTU). The hepatic lipid-peroxidation (LPO) and the activity of endogenous antioxidants, superoxide dismutase (SOD), and catalase (CAT) were not significantly altered in either of the doses. It appears that the action of P. nigrum on thyroid functions is mediated through its active alkaloid, piperine. We also suggest that a higher dose of piperine may inhibit thyroid function and serum glucose concentration in euthyroid individuals.

Alkaloids↗
PubMed2004

Isolation and synthesis of isodihydropiperlonguminine.

The hexane extract of dried fruits of Piper longum on fractionation afforded a new alkamide, isodihydropiperlonguminine and two phenyl propanoic acid derivatives. The structures of these compounds are established based on spectroscopic evidence and synthesis.

Fruit↗
PubMed1993

GLUT-4 NH2 terminus contains a phenylalanine-based targeting motif that regulates intracellular sequestration.

Expression of chimeras, composed of portions of two different glucose transporter isoforms (GLUT-1 and GLUT-4), in CHO cells had indicated that the cytoplasmic NH2 terminus of GLUT-4 contains important targeting information that mediates intracellular sequestration of this isoform (Piper, R. C., C. Tai, J. W. Slot, C. S. Hahn, C. M. Rice, H. Huang, D. E. James. 1992. J. Cell Biol. 117:729-743). In the present studies, the amino acid constituents of the GLUT-4 NH2-terminal targeting domain have been identified. GLUT-4 constructs containing NH2-terminal deletions or alanine substitutions within the NH2 terminus were expressed in CHO cells using a Sindbis virus expression system. Deletion of eight amino acids from the GLUT-4 NH2 terminus or substituting alanine for phenylalanine at position 5 in GLUT-4 resulted in a marked accumulation of the transporter at the plasma membrane. Mutations at other amino acids surrounding Phe5 also caused increased cell surface expression of GLUT-4 but not to the same extent as the Phe5 mutation. GLUT-4 was also localized to clathrin lattices and this colocalization was abolished when either the first 13 amino acids were deleted or when Phe5 was changed to alanine. To ascertain whether the targeting information within the GLUT-4 NH2-terminal targeting domain could function independently of the glucose transporter structure this domain was inserted into the cytoplasmic tail of the H1 subunit of the asialoglycoprotein receptor. H1 with the GLUT-4 NH2 terminus was predominantly localized to an intracellular compartment similar to GLUT-4 and was sequestered more from the cell surface than was the wild-type H1 protein. It is concluded that the NH2 terminus of GLUT-4 contains a phenylalanine-based targeting motif that mediates intracellular sequestration at least in part by facilitating interaction of the transporter with endocytic machinery located at the cell surface.

Amino Acid Sequence↗