Cooperative regulation of light-harvesting complex II phosphorylation via the plastoquinol and ferredoxin-thioredoxin system in chloroplasts

Light induces phosphorylation of photosystem II (PSII) proteins in chloroplasts by activating the protein kinase(s) via reduction of plastoquinone and the cytochrome b(6)f complex. The recent finding of high-light-induced inactivation of the phosphorylation of chlorophyll a/b-binding proteins (LHCII) of the PSII antenna in floated leaf discs, but not in vitro, disclosed a second regulatory mechanism for LHCII phosphorylation. Here we show that this regulation of LHCII phosphorylation is likely to be mediated by the chloroplast ferredoxin-thioredoxin system. We present a cooperative model for the function of the two regulation mechanisms that determine the phosphorylation level of the LHCII proteins in vivo, based on the following results: (i) Chloroplast thioredoxins f and m efficiently inhibit LHCII phosphorylation. (ii) A disulfide bond in the LHCII kinase, rather than in its substrate, may be a target component regulated by thioredoxin. (iii) The target disulfide bond in inactive LHCII kinase from dark-adapted leaves is exposed and easily reduced by external thiol mediators, whereas in the activated LHCII kinase the regulatory disulfide bond is hidden. This finding suggests that the activation of the kinase induces a conformational change in the enzyme. The active state of LHCII kinase prevails in chloroplasts under low-light conditions, inducing maximal phosphorylation of LHCII proteins in vivo. (iv) Upon high-light illumination of leaves, the target disulfide bond becomes exposed and thus is made available for reduction by thioredoxin, resulting in a stable inactivation of LHCII kinase.

Differential induction of plant volatile biosynthesis in the lima bean by early and late intermediates of the octadecanoid-signaling pathway

Plants are able to respond to herbivore damage with de novo biosynthesis of an herbivore-characteristic blend of volatiles. The signal transduction initiating volatile biosynthesis may involve the activation of the octadecanoid pathway, as exemplified by the transient increase of endogenous jasmonic acid (JA) in leaves of lima bean (Phaseolus lunatus) after treatment with the macromolecular elicitor cellulysin. Within this pathway lima bean possesses at least two different biologically active signals that trigger different biosynthetic activities. Early intermediates of the pathway, especially 12-oxo-phytodienoic acid (PDA), are able to induce the biosynthesis of the diterpenoid-derived 4,8, 12-trimethyltrideca-1,3,7,11-tetraene. High concentrations of PDA result in more complex patterns of additional volatiles. JA, the last compound in the sequence, lacks the ability to induce diterpenoid-derived compounds, but is highly effective at triggering the biosynthesis of other volatiles. The phytotoxin coronatine and amino acid conjugates of linolenic acid (e.g. linolenoyl-L-glutamine) mimic the action of PDA, but coronatine does not increase the level of endogenous JA. The structural analog of coronatine, the isoleucine conjugate of 1-oxo-indanoyl-4-carboxylic acid, effectively mimics the action of JA, but does not increase the level of endogenous JA. The differential induction of volatiles resembles previous findings on signal transduction in mechanically stimulated tendrils of Bryonia dioica.

Phosphorylation of light-harvesting complex II and photosystem II core proteins shows different irradiance-dependent regulation in vivo. Application of phosphothreonine antibodies to analysis of thylakoid phosphoproteins

An immunological approach using a polyclonal phosphothreonine antibody is introduced for the analysis of thylakoid protein phosphorylation in vivo. Virtually the same photosystem II (PSII) core phosphoproteins (D1, D2, CP43, and the psbH gene product) and the light-harvesting chlorophyll a/b complex II (LHCII) phosphopolypeptides (LHCB1 and LHCB2), as earlier identified by radiolabeling experiments, were recognized in both pumpkin and spinach leaves. Notably, the PSII core proteins and LHCII polypeptides were found to have a different phosphorylation pattern in vivo with respect to increasing irradiance. Phosphorylation of the PSII core proteins in leaf discs attained the saturation level at the growth light intensity, and this level was also maintained at high irradiances. Maximal phosphorylation of LHCII polypeptides only occurred at low light intensities, far below the growth irradiance, and then drastically decreased at higher irradiances. These observations are at variance with traditional studies in vitro, where LHCII shows a light-dependent increase in phosphorylation, which is maintained even at high irradiances. Only a slow restoration of the phosphorylation capacity for LHCII polypeptides at the low light conditions occurred in vivo after the high light-induced inactivation. Furthermore, if thylakoid membranes were isolated from the high light-inactivated leaves, no restoration of LHCII phosphorylation took place in vitro. However, both the high light-induced inactivation and low light-induced restoration of LHCII phosphorylation seen in vivo could be mimicked in isolated thylakoid membranes by incubating with reduced and oxidized dithiothreitol, respectively. We propose that stromal components are involved in the regulation of LHCII phosphorylation in vivo, and inhibition of LHCII phosphorylation under increasing irradiance results from reduction of the thiol groups in the LHCII kinase.

Effects of Momordica charantia fruit juice on islet morphology in the pancreas of the streptozotocin-diabetic rat

An investigation was made of the effect of Momordica charantia fruit juice on the distribution and number of alpha, beta and delta cells in the pancreas of streptozotocin (STZ)-induced diabetic rats using immunohistochemical methods. The results indicated that there was a significant (Student's t-test, P < 0.004) increase in the number of beta cells in M. charantia-treated animals when compared with untreated diabetics, however, their number was still significantly less than that obtained for normal rats. There was also a significant (P < 0.006) increase in the number of delta cells in STZ-diabetic rats compared to non-diabetic rats. This increase in the number of delta cells was not affected by M. charantia treatment. The number of alpha cells did not change significantly in M. charantia-treated rats when compared with untreated diabetic rats. Our results suggest that oral feeding of M. charantia fruit juice may have a role in the renewal of beta cells in STZ-diabetic rats or alternately may permit the recovery of partially destroyed beta cells.

Role of Selected Indian Plants in Management of Type 2 Diabetes: A Review

Type 2 diabetes has become a global epidemic. Modern medicines, despite offering a variety of effective treatment options, can have several adverse effects. Ayurveda, a science that uses herbal medicines extensively, originated in India. Of considerable interest is the adoption of Ayurveda by the mainstream medical system in some European countries (e.g., Hungary), emphasizing this modality is increasing worldwide recognition. From ancient times, some of these herbal preparations have been used in the treatment of diabetes. This paper reviews the accumulated literature for 10 Indian herbs that have antidiabetic activity and that have been scientifically tested. Few of these herbs, such as Momordica charantia, Pterocarpus marsupium, and Trigonella foenum greacum, have been reported to be beneficial for treating type 2 diabetes. Mechanisms such as the stimulating or regenerating effect on beta cells or extrapancreatic effects are proposed for the hypoglycemic action of these herbs.

Reassessing Coxcatlan Cave and the early history of domesticated plants in Mesoamerica

Reanalysis and direct accelerator mass spectrometry radiocarbon dating of the cucurbit assemblage from Coxcatlan Cave provide information on the timing and sequence of the initial appearance of three domesticated plants in the Tehuacán Valley (Puebla, Mexico) and allow reassessment of the overall temporal context of plant domestication in Mexico. Cucurbita pepo is the earliest documented domesticate in the cave, dating to 7,920 calibrated calendrical (cal) years B.P. The bottle gourd (Lagenaria siceraria) is dated at 7,200 cal years B.P. Cucurbita argyrosperma does not appear until 2,065 cal years B.P. The earlier identification of Cucurbita moschata specimens is not confirmed. Seventy-one radiocarbon dates, including 23 accelerator mass spectrometry dates on cucurbits, provide ample evidence of postdepositional vertical displacement of organic materials in the western half of Coxcatlan Cave, but they also indicate that the eastern half of the cave was largely undisturbed.

Root-secreted bitter triterpene modulates the rhizosphere microbiota to improve plant fitness

Underground microbial ecosystems have profound impacts on plant health^1-5. Recently, essential roles have been shown for plant specialized metabolites in shaping the rhizosphere microbiome^6-9. However, the potential mechanisms underlying the root-to-soil delivery of these metabolites remain to be elucidated¹⁰. Cucurbitacins, the characteristic bitter triterpenoids in cucurbit plants (such as melon and watermelon), are synthesized by operon-like gene clusters¹¹. Here we report two Multidrug and Toxic Compound Extrusion (MATE) proteins involved in the transport of their respective cucurbitacins, a process co-regulated with cucurbitacin biosynthesis. We further show that the transport of cucurbitacin B from the roots of melon into the soil modulates the rhizosphere microbiome by selectively enriching for two bacterial genera, Enterobacter and Bacillus, and we demonstrate that this, in turn, leads to robust resistance against the soil-borne wilt fungal pathogen, Fusarium oxysporum. Our study offers insights into how transporters for specialized metabolites manipulate the rhizosphere microbiota and thereby affect crop fitness.

Sorption and transport of sulfamethazine in agricultural soils amended with invasive-plant-derived biochar

Sulfonamides (SAs) are one of the most frequently used antibiotics in the veterinary industry, showing high mobility in soils. Objectives of this research were to determine the sorption, distribution coefficients and involvement of different ionic forms of sulfamethazine (SMZ), a representative SAs, and to evaluate the transport of SMZ in biochar treated soils. Biochars were produced from an invasive plant, burcucumber (Sicyos angulatus L.), under slow pyrolysis conditions at peak temperatures of 300 °C (biochar-300) and 700 °C (biochar-700), respectively. The abilities of the biochars to retain SMZ in loamy sand and sandy loam soils were examined under different pHs and SMZ loadings. Soil column experiments were performed with and without biochars addition. Results showed that biochar-700 had a high degree of SMZ retention, with resultant decreased pH in both soils. Modeled effective sorption coefficients (KD,eff) values indicated that the observed high SMZ retention at pH 3 could be attributed to the π-π electron donor-acceptor interaction and electrostatic cation exchange, whereas at pH 5 and 7, cation exchange was the main mechanisms responsible. There was no temporal retardation of SMZ in biochar treated soil as compared to the untreated soil. However, biochar-700 treatment achieved up to 89% and 82% increase in the SMZ retention in sandy loam and loamy sand soils, respectively. The overall results demonstrated that burcucumber biochar produced at higher temperature was effective in reducing the mobility of SMZ in the studied soils.

Isolation, purification and identification of ellagic acid derivatives, catechins, and procyanidins from the root bark of Anisophyllea dichostyla R. Br

The root bark of Anisophyllea dichostyla R. Br. is traditionally used in the Democratic Republic Congo for the treatment of several conditions such as anorexia, fatigue and intestinal infections. We have identified and quantitated several polyphenol antioxidants in the methanol extract of the root bark (120g). The polyphenol content (3.32g/kg) was predominantly ellagitannins (25%) and polyhydroxyflavan-3-ols (catechins and procyanidins, 75%) with 3'-O-methyl-3,4-methylenedioxo ellagic acid 4'-O-beta-d-glucopyranoside and (-)-epicatechin as the major species in each class. These two compounds and the following species were identified unequivocally by NMR spectroscopy: (+)-catechin, (-)-epicatechin 3-O-gallate, 3-O-methyl ellagic acid, 3,3'-di-O-methyl ellagic acid, 3'-O-methyl-3,4-methylenedioxo ellagic acid, 3'-O-methyl-3,4-methylenedioxo ellagic acid 4'-O-beta-d-glucopyranoside, and 3'-O-methyl ellagic acid 4-O-beta-d-xylopyranoside. The following additional compounds were purified by semi-preparative HPLC and tentatively identified on the basis of UV spectra, HPLC-ESI-MS and nano-ESI-MS-MS: (+)-catechin-3-O-beta-d-glucopyranoside, epicatechin-(4beta-->8)-catechin (procyanidin B(1)), epicatechin-(4beta-->8)-epicatechin (procyanidin B(2)), an (epi)catechin trimer, 3-O-methyl ellagic acid 4-O-beta-d-glucopyranoside, (-)-epicatechin 3-O-vanillate, 3,4-methylenedioxo ellagic acid 4'-O- beta-d-glucopyranoside, and 3,3'-di-O-methyl ellagic acid 4-O-beta-d-xylopyranoside. Fractionation of the raw extract by column chromatography on silicic acid yielded 10 fractions. In the hypoxanthine/xanthine oxidase antioxidant assay system, CC-9 which contained a range of polyphenols dominated by (-)-epicatechin-O-gallate proved to be the most potent antioxidant fraction (IC(50)=52 micro g/mL) in terms of ROS scavenging. In terms of XO inhibition CC-8, dominated by (epi)catechin trimer and which also contained appreciable amounts of 3'-O-methyl ellagic acid 4'-O-beta-d-xylopyranoside, as well as the catechins (+)-catechin-3-O-beta-d-glucopyranoside, epicatechin-(4beta-->8)-catechin (procyanidin B(1)), and (-)-epicatechin 3-O-gallate, proved to be the most potent (IC(50)=36 micro g/mL).

The effects of chaperones and the influence of protein assembly on peroxisomal protein import

Peroxisomal proteins are synthesized in the cytoplasm and post-translationally translocated into the organelle. The role of chaperones and protein folding in peroxisomal protein transport is still unclear. Translocation of proteins into mitochondria requires that precursor proteins assume an extended conformation; cytosolic chaperones are thought to help maintain this conformation. In contrast, peroxisomal protein import does not require unfolding of the targeted protein. However, the molecular chaperones Hsp70 and Hsp40 may be important for translocation. We present several lines of evidence that show that plant peroxisomal protein import is enhanced by chaperones. First, peroxisomes isolated from heat-shocked pumpkin seedling tissues exhibited increased protein import relative to control peroxisomes. Second, antibodies raised against wheat germ cytosolic Hsp70 and Escherichia coli Hsp90 inhibited import of the peroxisomal protein isocitrate lyase. To our knowledge, this is the first time that Hsp90 has been directly implicated in a protein transport event. Third, peroxisomal proteins were immunoprecipitated by wheat germ Hsp70 antibodies. We also present results that suggest that the efficiency of peroxisomal protein import is influenced by the structure of the targeted protein; monomeric isocitrate lyase was imported more efficiently than oligomeric isocitrate lyase. Taken together, these data demonstrate that the assembly state of peroxisomal proteins and the chaperones that may mediate those states are both important for efficient peroxisomal protein import.

Arsenic removal by natural and chemically modified water melon rind in aqueous solutions and groundwater

Contamination of groundwater with toxic arsenic (As) has become an emerging health and environmental problem around the world, which has seen significant attention amongst the scientists for development of new sorbents to remediate As-contaminated water. Here, we explored the arsenate (As(V)) and arsenite (As(III)) sorption to natural water melon rind (WMR), xanthated WMR and citric acid-modified WMR in aqueous solutions, and determined potential of the most potent sorbent for As removal in groundwater. Xanthated WMR (X-WMR) showed relatively higher As(V) and As(III) removal than the citric acid modified WMR (CA-WMR) and natural WMR. The maximum As(III) (99%) and As(V) (98%) removal was obtained at pH 8.2 and 4.6, respectively, by X-WMR at 4 mg L^-1 initial As(V) and As(III) concentrations and sorbent dose of 1 g L^-1. Langmuir isotherm model best fitted (R² of up to 0.96) the data both for As(III) and As(V) sorption to X-WMR. Sorption kinetics of As(V) and As(III) was well described (R² of up to 0.99) by the pseudo second-order model on surface of the X-WMR. Thermodynamic investigations revealed that As(V) and As(III) sorption was endothermic and spontaneous. The FTIR spectroscopy depicted the presence of different surface function groups (OH, COOH, S-bearing (C=S, S=O and S-S)) which were involved in As(V) and As(III) sequestration on the sorbents examined here. Significantly, X-WMR showed (up to 49%) greater As(III) and As(V) sorption than that of natural WMR. Our results demonstrated that X-WMR efficiently removed 94%-100% (n = 16) of As from As-contaminated drinking well water which possessed detectable concentrations of some anions (e.g., SO₄, CO₃, HCO₃). This study highlights that the X-WMR has potential to remove As, notably As(III), from solutions and drinking water, and might be utilized as a reactive medium for the treatment of As-contaminated water.

Larvicidal efficacy of some Cucurbitacious plant leaf extracts against Culex quinquefasciatus (Say)

Larvicidal efficacies of extracts of five species of Cucurbitacious plants, Momordica charantia, Trichosanthes anguina, Luffa acutangula, Benincasa cerifera and Citrullus vulgaris were tested against the late third larval age group of Culex quinquefasciatus. The larval mortality was observed after 24 h exposure. The LC50 values of M. charantia, T. anguina, L. acutangula, B. cerifera and C. vulgaris were 465.85, 567.81, 839.81, 1189.30 and 1636.04 ppm respectively.

Mediterranean vegetable soup consumption increases plasma vitamin C and decreases F2-isoprostanes, prostaglandin E2 and monocyte chemotactic protein-1 in healthy humans

Consumption of fruits and vegetables is associated with a reduced risk of death from all causes including heart disease and stroke. In this work, the bioavailability of vitamin C from a Mediterranean vegetable soup (gazpacho) constituted mainly of tomato, pepper and cucumber, and its influence on plasma vitamin C, 8-epi-prostaglandin F(2alpha) (8-epi-PGF2alpha), prostaglandin E2 (PGE2), monocyte chemotactic protein-1 (MCP-1), and the cytokines/tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-6 concentrations in a healthy human population were assessed. Six men and six women consumed 500 ml of commercial gazpacho per day for 14 days, corresponding to an intake of 78 mg of ascorbic acid per day. There were no differences (P = .22) in baseline plasma vitamin C concentrations between the men and women. The maximum increase (P < .05) in plasma vitamin C occurred 4 h postdose in both men and women. Vitamin C concentrations were significantly higher (P < .03) on Days 7 and 14 of the intervention. Baseline concentrations of uric acid and 8-epi-PGF2alpha were significantly higher (P < or = .032) in men than in women. Baseline concentrations of 8-epi-PGF2alpha decreased significantly (P < or = .05) by Day 14 of the intervention. A significant inverse correlation was observed between vitamin C and 8-epi-PGF2alpha (r = -.415, P = .049). Baseline concentrations of PGF2 and MCP-1 were significantly higher (P< or = .025) in men than in women but decreased significantly (P< or = .05) by Day 14 of the intervention. No effect on TNF-alpha, IL-1beta and IL-6 was observed at Day 14 of the intervention. Drinking gazpacho (500 ml/day) significantly increases plasma concentrations of vitamin C and significantly decreases 8-epi-PGF2alpha, PGE2 and MCP-1 concentrations in healthy humans.

Reduced adiposity in bitter melon (Momordica charantia) fed rats is associated with lower tissue triglyceride and higher plasma catecholamines

Slower weight gain and less visceral fat had been observed when rats fed a high-fat diet were supplemented with freeze-dried bitter melon (BM) juice; the metabolic consequences and possible mechanism(s) were further explored in the present study. In a 4-week experiment, rats were fed a low-fat (70 g/kg) or a high-fat (300 g/kg) diet with or without BM (7.5 g/kg or 0.75%). BM-supplemented rats had lower energy efficiency, visceral fat mass, plasma glucose and hepatic triacylglycerol, but higher serum free fatty acids and plasma catecholamines. In the second experiment, 7-week BM supplementation in high-fat diet rats led to a lowering of hepatic triacylglycerol (P<0.05) and steatosis score (P<0.05) similar to those in rats fed a low-fat diet. BM supplementation did not affect serum and hepatic cholesterol. However, plasma epinephrine and serum free fatty acid concentrations were increased (P<0.05). In the third experiment, BM(7.5 and 15 g/kg) and 1.5 % BM lowered triacylglycerol concentration in red gastrocnemius and tibialis anterior (P<0.05) muscle, but a dose-response effect was not observed. These data suggest that chronic BM feeding leads to a general decrease in tissue fat accumulation and that such an effect is mediated in part by enhanced sympathetic activity and lipolysis. BM or its bioactive ingredient(s) could be used as a dietary adjunct in the control of body weight and blood glucose.

Subcellular localization and membrane topology of the melon ethylene receptor CmERS1

Ethylene receptors are multispanning membrane proteins that negatively regulate ethylene responses via the formation of a signaling complex with downstream elements. To better understand their biochemical functions, we investigated the membrane topology and subcellular localization of CmERS1, a melon (Cucumis melo) ethylene receptor that has three putative transmembrane domains at the N terminus. Analyses using membrane fractionation and green fluorescent protein imaging approaches indicate that CmERS1 is predominantly associated with the endoplasmic reticulum (ER) membrane. Detergent treatments of melon microsomes showed that the receptor protein is integrally bound to the ER membrane. A protease protection assay and N-glycosylation analysis were used to determine membrane topology. The results indicate that CmERS1 spans the membrane three times, with its N terminus facing the luminal space and the large C-terminal portion lying on the cytosolic side of the ER membrane. This orientation provides a platform for interaction with the cytosolic signaling elements. The three N-terminal transmembrane segments were found to function as topogenic sequences to determine the final topology. High conservation of these topogenic sequences in all ethylene receptor homologs identified thus far suggests that these proteins may share the same membrane topology.

Acid-activated biochar increased sulfamethazine retention in soils

Sulfamethazine (SMZ) is an ionizable and highly mobile antibiotic which is frequently found in soil and water environments. We investigated the sorption of SMZ onto soils amended with biochars (BCs) at varying pH and contact time. Invasive plants were pyrolyzed at 700 °C and were further activated with 30 % sulfuric (SBBC) and oxalic (OBBC) acids. The sorption rate of SMZ onto SBBC and OBBC was pronouncedly pH dependent and was decreased significantly when the values of soil pH increased from 3 to 5. Modeled effective sorption coefficients (K D,eff) values indicated excellent sorption on SBBC-treated loamy sand and sandy loam soils for 229 and 183 L/kg, respectively. On the other hand, the low sorption values were determined for OBBC- and BBC700-treated loamy sand and sandy loam soils. Kinetic modeling demonstrated that the pseudo second order model was the best followed by intra-particle diffusion and the Elovich model, indicating that multiple processes govern SMZ sorption. These findings were also supported by sorption edge experiments based on BC characteristics. Chemisorption onto protonated and ligand containing functional groups of the BC surface, and diffusion in macro-, meso-, and micro-pores of the acid-activated BCs are the proposed mechanisms of SMZ retention in soils. Calculated and experimental q e (amount adsorbed per kg of the adsorbent at equilibrium) values were well fitted to the pseudo second order model, and the predicted maximum equilibrium concentration of SBBC for loamy sand soils was 182 mg/kg. Overall, SBBC represents a suitable soil amendment because of its high sorption rate of SMZ in soils.

Cytotoxicity and antimicrobial activity of goniothalamin isolated fromBryonopsis laciniosa

The cytotoxicity and antimicrobial activity of goniothalamin isolated from Bryonopsis laciniosa was investigated. Goniothalamin showed potent cytotoxicity with LC50 values (5.03 microg/mL) comparable with the reference standard agent, gallic acid. It also showed weak antibacterial and significant antifungal activity against a wide range of gram positive and gram negative bacteria and fungi. The antibacterial (minimum inhibitory concentration) effect against Bacillus cereus and Shigella shiga was found to be 64 microg/mL.

Functional analysis of cytochrome P450 genes linked with acetamiprid resistance in melon aphid, Aphis gossypii

Cytochrome P450 monooxygenases (P450s) are highly conserved multifunctional enzymes that play crucial roles in insecticide resistance development. In this study, the molecular mechanisms of P450s in acetamiprid resistance development to melon aphid, Aphis gossypii was investigated. Acetamiprid resistant (32.64-fold resistance) population (Ace-R) of A. gossypii was established by continuous selection with acetamiprid for 24 generations. Quantitative Real Time PCR was carried out to analyze the expression of P450 genes in both acetamiprid resistant (Ace-R) and susceptible (Ace-S) strains. Result showed that nine genes (CYP6CY14, CYP6DC1, CYP6CZ1, CYP6DD1, CYP6CY5, CYP6CY9, CYP6DA1, CYP6CY18, and CYP6CY16) of CYP3 clade, four genes (CYP302A1, CYP315A1, CYP301A1, and CYP314A1) of CYP2 clade, two genes (CYP4CK1, CYP4G51) of CYP4 clade and three genes (CYP306A1, CYP305E1, CYP307A1) of mitochondrial clade (Mito clad) were significantly up-regulated, in Ace-R compared to Ace-S strain. Whilst CYP4CJ2 gene from (CYP4 clade) was significantly down-regulated in Ace-R strain. Furthermore, RNA interference-mediated knockdown of CYP6CY14, CYP6DC1, and CYP6CZ1 genes significantly increased the sensitivity of Ace-R strain to acetamiprid. Taken together, this study showed that P450 genes especially CYP6CY14, CYP6DC1 and CYP6CZ1 are potentially involved in acetamiprid resistance development in A. gossypii. This study could be useful to understand the molecular basis of acetamiprid resistance mechanism in A. gossypii.

Upper airway edema resulting from use of Ecballium elaterium

OBJECTIVES

To present a rare occurrence in ear, nose and throat practice of upper airway allergic edema from use of juice extracted from the fruit of Ecballium elaterium.

INTRODUCTION

Ecballium elaterium is a plant indigenous to the Mediterranean region that bears the common name squirting cucumber. Many people in this region for the treatment of sinusitis use the juice of its fruit. However, allergy-prone patients after using it may sometimes present with edema at various sites of the upper respiratory tract. Otolaryngologists are frequently asked to diagnose and treat such an emergency situation.

STUDY DESIGN

Retrospective review of the records of 42 patients with this condition during the last 4 years.

METHODS

Patient records were retrospectively reviewed for age, sex, presenting symptoms, physical examination, and medical treatment. Seasonal distribution and data from the history of the patients were also considered. Skin prick and prick-to-prick testing to various allergens was performed in 12 patients.

RESULTS

Most of the patients presented with localized swelling of the uvula and the nasal mucosa, whereas in the remainder of the patients various sites of swelling of the upper respiratory tract were observed. Skin tests elicited positive reactions to pollen weeds and to various fruits of the Cucurbitaceae family. Treatment of the patients with corticosteroids and antihistamines resulted in an uneventful recovery, and we did not need to resort to therapeutic modalities, such as intubation or tracheotomy.

CONCLUSIONS

We think a further study of the pharmaceutical properties of the plant's fruit juice is needed, especially regarding its curative properties of rhinitis and sinusitis. However, adverse reactions in some patients with a positive history of allergy should always be considered.

Pumpkin-seed oil modulates the effect of felodipine and captopril in spontaneously hypertensive rats

Natural products like pumpkin-seed oil (PSO) may modify the potency of the calcium antagonist felodipine (FEL) or angiotensin-converting enzyme inhibitor (ACE-inhibitor), captopril (CPT) in modulating the biochemical derangement in blood, heart and kidney as well as blood pressure and heart rate of spontaneously hypertensive rats (SHR) were investigated. SHR were treated orally with FEL at a dose of 0. 45 mg kg(-1) body wt. or CPT at a dose of 9 mg kg(-1) body wt. once daily for 4 weeks. PSO was administered at a dose of 40 mg kg(-1) body wt. alone or with FEL or CPT in the previous respective dose regimen for the same period to SHR. This study showed that hypertension induced increments the content of malondialdehyde (MDA) by 55% and 38% as well as the activity of glutathione peroxidase (GSH-Px) by 26% and 23% in heart and kidney, respectively, accompanied by reductions in the activity of myocardial superoxide dismutase (SOD) from 3.40+/-0.17 to 2.42+/-0.19 U mg protein(-1)and contents of glutathione (GSH) and protein thiols (PrSHs) in different tissues of SHR as compared to normotensive rats. Treatment of SHR with FEL or CPT monotherapy or combined with PSO produced improvement in the measured free radical scavengers in the heart and kidney. Our results also showed that pretreatment of SHR with PSO for 4 weeks then i.v. administration of FEL or CPT produced a significant beneficial hypotensive action. The results were explained in the light of the antioxidant properties of PSO. Therefore, it is concluded that concomitant administration of FEL or CPT with natural antioxidants can yield a beneficial therapeutic effect and retard the progression of hypertension.

Regulating the gut microbiota and SCFAs in the faeces of T2DM rats should be one of antidiabetic mechanisms of mogrosides in the fruits of Siraitia grosvenorii

ETHNOPHARMACOLOGICAL RELEVANCE

The Siraitia grosvenorii fruits extract (SG, in which mogrosides are the main components), considered as a non-nutritional sweetener, has an antidiabetic effect. Our previous studies have confirmed that an extract of mogrosides being rich in triterpene glycosides with 1-3 glucosyl residues, designated as low-polar S. grosvenorii glycosides (L-SGgly), had a significant antidiabetic effect. However, whether the mechanism through impacting on gut microbiota to exert the antidiabetic effect of mogrosides remains unclear.

AIMS OF THE STUDY

To explore the potential mechanism of mogrosides (SG and L-SGgly) on gut microbiota and faecal metabolites in the treatment of diabetes.

STUDY DESIGN AND METHODS

In this study, the effects of SG and L-SGgly on gut microbiota and faecal endogenous metabolites were explored by sequencing the 16S rRNA V3-V4 region of gut microbiota, and detecting with gas chromatography-mass spectrometry (GC-MS) and liquid chromatography quadrupole time-of-flight MS (LC-Q-TOF/MS), respectively. In particular, correlation analyses revealed how these influences affect the anti-hyperglycaemic effect, to give the underlying antidiabetic mechanisms of the mogrosides in S. grosvenorii fruits.

RESULTS

After a 14-day treatment with SG and L-SGgly for type 2 diabetes mellitus (T2DM) rats induced by a high-fat diet (HFD) and streptozotocin (STZ), the disordered gut microbiota in the faeces of T2DM rats were recovered. At the same time, the short-chain fatty acids (SCFAs) concentration significantly increased and the deoxycholic acid and 1β-hydroxycholic acid content decreased in the faeces of T2DM rats. Moreover, correlation analyses provided the evidences that gut microbiota and its metabolites could be the target for exerting the anti-hyperglycaemic effects of SG and L-SGgly. Especially, Elusimicrobium, Lachnospiraceae_UCG-004, acetate, butyrate, and 1β-hydroxycholic acid would be the potential dominant bacteria and biomarkers for SG and L-SGgly in reducing the blood glucose and insulin resistance of T2DM rats.

CONCLUSION

It is the first time that a mechanism of targeting on gut microbiota for the antidiabetic effect of mogrosides in S. grosvenorii fruits has been proposed.

Experimental assessment of antidiarrheal and antisecretory activity of 80% methanolic leaf extract of Zehneria scabra in mice

BACKGROUND

The leaf of Zehneria scabra is traditionally used for the management of diarrhea in Ethiopia. Its use, however, has not been scientifically validated for safety and efficacy. The aim of this study was to investigate antidiarrheal and antisecretory effects of hydroalcolic leaf extract of Z. scabra in mice models.

METHODS

For each of antidiarrheal, gastrointestinal motility and antisecretory activity study Swiss albino mice were divided in to five groups. Group I was treated as control group and received 10 ml/kg of 2% Tween-80 orally; Group II served as a positive control and took standard drug in each of the experiments orally; Group III, IV and V were test groups which received the methanolic extract orally at 100, 200 and 400 mg/kg, respectively. Depending on the model total weight of fecal output, total weight of wet feces, total number of fecal output, number of wet faeces, length of intestinal transit and intestinal weight were collected. Finally, data were analyzed using one-way ANOVA followed by Tukey's post test.

RESULT

In castor oil induced diarrhea model, the extract dose produced a significant reduction in mean stool score (1.94 ± 0.102) at 200 mg/kg. Moreover, the 100, 200, and 400 mg/kg doses inhibited stool frequency by 40, 45 and 55%, respectively. All test doses of extract and loperamide (3mg/kg) reduced fecal fluid content significantly (p<0.01). The 100 mg/kg dose of extract produced 25.74% reduction of fluid content (p<0.001) while both 200 and 400 mg/kg showed 29.70 % (p<0.001) compared to negative control group.

CONCLUSION

The extract of Zehineria scabra showed antidiarrheal and antisecretory activity in mice model. Moreover, the extract found to be safe at dose of 2000mg/kg in mice model. The findings suggest the validity of the acclaimed effect of Zehineria scabra as antidiarrheal agent in Ethiopian traditional herbal medicine.

Arsenic exposure, dietary patterns, and skin lesion risk in bangladesh: a prospective study

Dietary factors are believed to modulate arsenic toxicity, potentially influencing risk of arsenical skin lesions. The authors evaluated associations among dietary patterns, arsenic exposure, and skin lesion risk using baseline food frequency questionnaire data collected in the Health Effects of Arsenic Longitudinal Study (HEALS) in Araihazar, Bangladesh (2000-2009). They identified dietary patterns and estimated dietary pattern scores using factor analysis. Scores were tested for association with incident skin lesion risk and interaction with water arsenic exposure by using ∼6 years of follow-up data (814 events among 9,677 individuals) and discrete time hazards models (adjusting for key covariates). The authors identified 3 clear dietary patterns: the "gourd and root," "vegetable," and "animal protein" patterns. The gourd and root pattern score was inversely associated with skin lesion risk (P(trend) = 0.001), with hazard ratios of 0.86, 0.73, and 0.69 for the second, third, and fourth highest quartiles. Furthermore, the association between water arsenic and skin lesion incidence was stronger among participants with low gourd and root scores (multiplicative P(interaction) < 0.001; additive P(interaction) = 0.05). The vegetable pattern and animal protein pattern showed similar but weaker associations and interactions. Eating a diet rich in gourds and root vegetables and increasing dietary diversity may reduce arsenical skin lesion risk in Bangladesh.

Momordica charantia (Bitter Gourd) peel, pulp, seed and whole fruit extract inhibits mouse skin papillomagenesis

The present study was designed to elucidate the inhibitory potential of Momordica charantia (Bitter Gourd) peel, pulp, seed and whole fruit extract on mouse skin papillomagensis with the modulatory influence of biotransformation system enzymes. Topical application of Momordica whole fruit extract (100 microl/animal per day) during the peri-initiation stage (1 week before and 2 weeks after initiation) by 7,12-dimethylbenz[a]anthracene (DMBA) and/or during the tumor promotion stage reduced the (i) tumor burden to 4.26, 3.72 and 3.11 (positive control value: 5.42); (ii) cumulative number of papillomas to 81, 67 and 53 (positive control value: 103); and (iii) percent incidence of mice bearing papillomas to 100, 94 and 94, respectively (positive control value: 100). In a comparison of the anticarcinogenic efficacy of Momordica peel, pulp, seed and whole fruit extract (100 microl/animal per day), after topical treatment during the peri-initiation and during the tumor promotion stage, revealed the modulation of the (i) tumor burden (tumors/mouse) to 3.06, 3.61, 3.17 and 3.11; (ii) cumulative number of papillomas to 49, 65, 54 and 53; and (iii) percent incidence of mice bearing papillomas to 84, 100, 94 and 94, respectively. Significant elevation in the sulfhydryl (-SH) level was observed in the liver and skin tissues by the topical treatment of Momordica peel, pulp, seed and whole fruit extract. Elevation in the hepatic levels of cytosolic glutathione S-transferase (GST) and microsomal cytochrome b, was also observed by the topical treatment of Momordica peel, seed and whole fruit extract. The results suggest the maximum chemopreventive potential is in the Momordica peel. Equivocal efficacy is in the Momordica seed and whole fruit extract. Biotransformation system enzymes may be the cause of this reduced papillomagenesis.