Acute and Subacute Toxicity and Cytotoxicity of Opuntia Dillenii (Ker-Gawl) Haw. Seed Oil and Its Impact on the Isolated Rat Diaphragm Glucose Absorption.

This study aims to assess the safety of the Opuntia dillenii (Ker-Gawl) haw. seed oil (ODSO) and its effect on the glucose absorption activity of the isolated rat hemidiaphragm. This oil's safety was studied by exploring its acute (doses 1, 3, 5, and 7 mL/kg) and subacute (doses 1 and 2 mL/kg) toxicities in albino mice and Wistar rats, respectively. The safety of the ODSO was also assessed by studying its effect on the HepG2 cell viability in vitro. The effect of ODSO, or combined with the insulin, on the glucose absorption activity of isolated rat hemidiaphragm was evaluated at the dose 1 g/L in vitro. The results demonstrated the safety of ODSO. Indeed, this study showed that this oil does not produce any mortality or signs of toxicity after the single-dose administration in mice. Additionally, the daily intake of the ODSO during four weeks does not induce a significant variation in the biochemical parameters and body weight of rats compared with the control group. Besides, the cell viability of HepG2 did not change in the presence of ODSO. On the other hand, the ODSO increased the glucose absorption activity of the isolated rat hemidiaphragm, and this activity was significantly enhanced when combined with insulin. This study confirms, on one side, the safety of this oil and its efficacy and, on the other side, encourages its potential use as a complement to treat diabetes.

A randomized, phase 1, placebo-controlled trial of APG-157 in oral cancer demonstrates systemic absorption and an inhibitory effect on cytokines and tumor-associated microbes.

BACKGROUND: Although curcumin's effect on head and neck cancer has been studied in vitro and in vivo, to the authors' knowledge its efficacy is limited by poor systemic absorption from oral administration. APG-157 is a botanical drug containing multiple polyphenols, including curcumin, developed under the US Food and Drug Administration's Botanical Drug Development, that delivers the active components to oromucosal tissues near the tumor target. METHODS: A double-blind, randomized, placebo-controlled, phase 1 clinical trial was conducted with APG-157 in 13 normal subjects and 12 patients with oral cancer. Two doses, 100 mg or 200 mg, were delivered transorally every hour for 3 hours. Blood and saliva were collected before and 1 hour, 2 hours, 3 hours, and 24 hours after treatment. Electrocardiograms and blood tests did not demonstrate any toxicity. RESULTS: Treatment with APG-157 resulted in circulating concentrations of curcumin and analogs peaking at 3 hours with reduced IL-1ß, IL-6, and IL-8 concentrations in the salivary supernatant fluid of patients with cancer. Salivary microbial flora analysis showed a reduction in Bacteroidetes species in cancer subjects. RNA and immunofluorescence analyses of tumor tissues of a subject demonstrated increased expression of genes associated with differentiation and T-cell recruitment to the tumor microenvironment. CONCLUSIONS: The results of the current study suggested that APG-157 could serve as a therapeutic drug in combination with immunotherapy. LAY SUMMARY: Curcumin has been shown to suppress tumor cells because of its antioxidant and anti-inflammatory properties. However, its effectiveness has been limited by poor absorption when delivered orally. Subjects with oral cancer were given oral APG-157, a botanical drug containing multiple polyphenols, including curcumin. Curcumin was found in the blood and in tumor tissues. Inflammatory markers and Bacteroides species were found to be decreased in the saliva, and immune T cells were increased in the tumor tissue. APG-157 is absorbed well, reduces inflammation, and attracts T cells to the tumor, suggesting its potential use in combination with immunotherapy drugs.

Antioxidant activity and absorption of cyanidin-3-O-glucoside liposomes in GES-1 cells in vitro.

The use of anthocyanins are limited by their chemical properties. Recent evidence suggests Cyanidin-3-O-glucoside (C3 G) liposomes via the ethanol injection method exhibit improved stability. In the current study, the characterization and cell absorption of C3 G liposomes were explored via transmission electron microscopy and flow cytometry. The internalization of the C3 G liposomes across the gastric epithelial cell monolayer (GES-1 cells) were investigated. Results showed that the particle size and encapsulation efficiency were 234 ± 9.35 nm and 75.0% ± 0.001, respectively. The total antioxidant capacity (T-AOC) and malondialdehyde (MDA) content were used to evaluate the antioxidant activity of C3 G liposomes. The C3 G liposomes can obviously increased T-AOC and decreased the MDA content.Collectively, C3 G liposomes protected human GES-1 cells from gastric mucosal injury induced by H2O2 by activating the related antioxidant pathway. Our research could provide a new effective treatment strategy for the absorption of stomach drugs.Abbreviations: C3G: Cyanidin-3-O-glucoside; LP: Liposome; GES-1 cells: Human gastric epithelial cell lines; FBS: Fetal Bovine Serum; PBS: Phosphate-buffered saline; PC: Phosphatidylcholine; CH: Cholesterol; MDA: Malondialdehyde; TEM: Transmission electron microscope; FCM: Flow cytometry; FITC: Fluorescein isothiocyanate; DAPI: 4', 6-diamidino-2phenylidole; FT-IR: Fourier Transform infrared spectroscopy; PFA: Paraformaldehyde.

The glutamine transporter ASCT2 (SLC1A5) promotes tumor growth independently of the amino acid transporter LAT1 (SLC7A5).

The transporters for glutamine and essential amino acids, ASCT2 (solute carrier family 1 member 5, SLC1A5) and LAT1 (solute carrier family 7 member 5, SLC7A5), respectively, are overexpressed in aggressive cancers and have been identified as cancer-promoting targets. Moreover, previous work has suggested that glutamine influx via ASCT2 triggers essential amino acids entry via the LAT1 exchanger, thus activating mechanistic target of rapamycin complex 1 (mTORC1) and stimulating growth. Here, to further investigate whether these two transporters are functionally coupled, we compared the respective knockout (KO) of either LAT1 or ASCT2 in colon (LS174T) and lung (A549) adenocarcinoma cell lines. Although ASCT2KO significantly reduced glutamine import (>60% reduction), no impact on leucine uptake was observed in both cell lines. Although an in vitro growth-reduction phenotype was observed in A549-ASCT2KO cells only, we found that genetic disruption of ASCT2 strongly decreased tumor growth in both cell lines. However, in sharp contrast to LAT1KO cells, ASCT2KO cells displayed no amino acid (AA) stress response (GCN2/EIF2a/ATF4) or altered mTORC1 activity (S6K1/S6). We therefore conclude that ASCT2KO reduces tumor growth by limiting AA import, but that this effect is independent of LAT1 activity. These data were further supported by in vitro cell proliferation experiments performed in the absence of glutamine. Together these results confirm and extend ASCT2's pro-tumoral role and indicate that the proposed functional coupling model of ASCT2 and LAT1 is not universal across different cancer types.

EDTA-facilitated toxic tolerance, absorption and translocation and phytoremediation of lead by dwarf bamboos.

Bamboos are considered as potential plants for phytoremediation. However, the mechanisms of EDTA-assisted bamboo for lead (Pb) control has not been described. The objective of this study was to examine the tolerance and behaviors of Pb to screen bamboos for Pb-contaminated soil and to explore the effects of EDTA on their phytoremediation. In this regard, five dwarf bamboos were treated with various doses Pb (0-1500 mg kg-1) and/or EDTA (500 or 250-1000 mg kg-1) to investigate antioxidant systems and Pb accumulation/species. Our findings showed that different doses of Pb significantly affect lipid peroxidation and antioxidant compounds in studied bamboos. EDTA increased the absorption of soil Pb2+ in all tissues with increasing Pb doses, while the Pb concentrations in all bamboo roots was higher than those in other tissues. Among these plants, Arundinaria argenteostriata (AA) and A. fortunei (AF) showed greater oxidative tolerance than other bamboos. Moreover, Pb accumulation showed the highest values in AA and AF plants relative to other bamboos. With increasing EDTA doses, levels of reducible and residual Pb decreased but the weak acid-soluble and total Pb increased in Pb-stressed AA/AF soils. Similarly, EDTA increased Pb2+ concentration in both bamboo tissues, while the Pb2+ level in leaves was higher than that in other organs at the highest EDTA dose. This study provides the first comprehensive evidence regarding EDTA enhancing the availability, absorption, and translocation of Pb in bamboo/soil, suggesting the application of EDTA may be an effective strategy for phytoremediation with two Arundinaria bamboos in Pb-contaminated soils.

CD14 is a key mediator of both lysophosphatidic acid and lipopolysaccharide induction of foam cell formation.

Macrophage uptake of oxidized low-density lipoprotein (oxLDL) plays an important role in foam cell formation and the pathogenesis of atherosclerosis. We report here that lysophosphatidic acid (LPA) enhances lipopolysaccharide (LPS)-induced oxLDL uptake in macrophages. Our data revealed that both LPA and LPS highly induce the CD14 expression at messenger RNA and protein levels in macrophages. The role of CD14, one component of the LPS receptor cluster, in LPA-induced biological functions has been unknown. We took several steps to examine the role of CD14 in LPA signaling pathways. Knockdown of CD14 expression nearly completely blocked LPA/LPS-induced oxLDL uptake in macrophages, demonstrating for the first time that CD14 is a key mediator responsible for both LPA- and LPS-induced oxLDL uptake/foam cell formation. To determine the molecular mechanism mediating CD14 function, we demonstrated that both LPA and LPS significantly induce the expression of scavenger receptor class A type I (SR-AI), which has been implicated in lipid uptake process, and depletion of CD14 levels blocked LPA/LPS-induced SR-AI expression. We further showed that the SR-AI-specific antibody, which quenches SR-AI function, blocked LPA- and LPS-induced foam cell formation. Thus, SR-AI is the downstream mediator of CD14 in regulating LPA-, LPS-, and LPA/LPS-induced foam cell formation. Taken together, our results provide the first experimental evidence that CD14 is a novel connecting molecule linking both LPA and LPS pathways and is a key mediator responsible for LPA/LPS-induced foam cell formation. The LPA/LPS-CD14-SR-AI nexus might be the new convergent pathway, contributing to the worsening of atherosclerosis.

Zinc oxide nanoparticles provide anti-cholera activity by disrupting the interaction of cholera toxin with the human GM1 receptor.

Vibrio cholerae causes cholera and is the leading cause of diarrhea in developing countries, highlighting the need for the development of new treatment strategies to combat this disease agent. While exploring the possibility of using zinc oxide (ZnO) nanoparticles (NPs) in cholera treatment, we previously found that ZnO NPs reduce fluid accumulation in mouse ileum induced by the cholera toxin (CT) protein. To uncover the mechanism of action of ZnO NPs on CT activity, here we used classical (O395) and El Tor (C6706) V. cholerae biotypes in growth and biochemical assays. We found that a ZnO NP concentration of 10 µg/ml did not affect the growth rates of these two strains, nor did we observe that ZnO NPs reduce the expression levels of CT mRNA and protein. It was observed that ZnO NPs form a complex with CT, appear to disrupt the CT secondary structure, and block its interaction with the GM1 ganglioside receptor in the outer leaflet of the plasma membrane in intestinal (HT-29) cells and thereby reduce CT uptake into the cells. In the range of 2.5-10 µg/ml, ZnO NPs exhibited no cytotoxicity on kidney (HEK293) and HT-29 cells. We conclude that ZnO NPs prevent the first step in the translocation of cholera toxin into intestinal epithelial cells without exerting measurable toxic effects on HEK293 and HT-29 cells.

Skeletal muscle-specific overexpression of heat shock protein 72 improves skeletal muscle insulin-stimulated glucose uptake but does not alter whole body metabolism.

AIMS: The induction of heat shock protein 72 (Hsp72) via heating, genetic manipulation or pharmacological activation is metabolically protective in the setting of obesity-induced insulin resistance across mammalian species. In this study, we set out to determine whether the overexpression of Hsp72, specifically in skeletal muscle, can protect against high-fat diet (HFD)-induced obesity and insulin resistance. MATERIALS AND METHODS: An Adeno-Associated Viral vector (AAV), designed to overexpress Hsp72 in skeletal muscle only, was used to study the effects of increasing Hsp72 levels on various metabolic parameters. Two studies were conducted, the first with direct intramuscular (IM) injection of the AAV:Hsp72 into the tibialis anterior hind-limb muscle and the second with a systemic injection to enable body-wide skeletal muscle transduction. RESULTS: IM injection of the AAV:Hsp72 significantly improved skeletal muscle insulin-stimulated glucose clearance in treated hind-limb muscles, as compared with untreated muscles of the contralateral leg when mice were fed an HFD. Despite this finding, systemic administration of AAV:Hsp72 did not improve body composition parameters such as body weight, fat mass or percentage body fat, nor did it lead to an improvement in fasting glucose levels or glucose tolerance. Furthermore, no differences were observed for other metabolic parameters such as whole-body oxygen consumption, energy expenditure or physical activity levels. CONCLUSIONS: At the levels of Hsp72 over-expression reported herein, skeletal muscle-specific Hsp72 overexpression via IM injection has the capacity to increase insulin-stimulated glucose clearance in this muscle. However, upon systemic injection, which results in lower muscle Hsp72 overexpression, no beneficial effects on whole-body metabolism are observed.

Global functions of extracellular, transmembrane and cytoplasmic domains of organic solute transporter ß-subunit.

Transport of bile acids across the basolateral membrane of the intestinal enterocyte is carried out by the organic solute transporter (Ost) composed of a seven-transmembrane domain (TMD) subunit (Ostα) and an ancillary single TMD subunit (Ostß). Although previous investigations have demonstrated the importance of the TMD of Ostß for its activity, further studies were conducted to assess the contributions of other regions of the Ostß subunit. Transport activity was retained when Ostß was truncated to contain only the TMD with 15 additional residues on each side and co-expressed with Ostα, whereas shorter fragments were inactive. To probe the broader functions of Ostß segments, chimeric proteins were constructed in which N-terminal, TMD or C-terminal regions of Ostß were fused to corresponding regions of receptor activity-modifying protein (RAMP1), a single TMD protein required by several seven-TMD G-protein-coupled receptors including the calcitonin receptor-like receptor (CLR). Ostß/RAMP1 chimeras were expressed with Ostα and CLR. As expected, replacing the Ostß TMD abolished transport activity; however, replacing either the entire N-terminal or entire C-terminal domain of Ostß with RAMP1 sequences did not prevent plasma membrane localization or the ability to support [3H]taurocholate uptake. Co-immunoprecipitation experiments revealed that the C-terminus of Ostß is a previously unrecognized site of interaction with Ostα. All chimeras containing N-terminal RAMP1 segments allowed co-expressed CLR to respond to agonists with strong increases in cyclic AMP. These results provide new insights into the structure and function of the heteromeric Ost transporter complex.

The Effects of Different Degrees of Procyanidin Polymerization on the Nutrient Absorption and Digestive Enzyme Activity in Mice.

Proanthocyanidins, including polymers with both low and high degrees of polymerization, are the focus of intensive research worldwide due to their high antioxidant activity, medicinal applications, and pharmacological properties. However, the nutritional value of these compounds is limited because they readily form complexes with proteins, polysaccharides, and metal ions when consumed. In this study, we examined the effects of proanthocyanidins with different degrees of polymerization on white mice. Twenty-four male white mice were randomly divided into three groups of eight mice each and fed proanthocyanidins with a low degree of polymerization or a high degree of polymerization or a distilled water control via oral gavage over a 56-day period. We examined the effects of these proanthocyanidins on digestive enzyme activity and nutrient absorption. Compared to the control group, the group fed high-polymer proanthocyanidins exhibited a significant reduction in net body mass, total food intake, food utility rate, amylase activity, protease activity, and major nutrient digestibility (p < 0.05), while the group fed low-polymerization proanthocyanidins only exhibited significant reductions in total food intake, α-amylase activity, and apparent digestibility of calcium and zinc (p < 0.05). Therefore, proanthocyanidins with a high degree of polymerization had a greater effect on digestive enzyme activity and nutrient absorption than did those with a low degree of polymerization. This study lays the foundation for elucidating the relationship between procyanidin polymerization and nutrient uptake, with the aim of reducing or eliminating the antinutritional effects of polyphenols.

Increasing efficacy and reducing systemic absorption of brimonidine tartrate ophthalmic gels in rabbits.

Systemic absorption of ocularly administered Brimonidine Tartrate has been reported to give rise to several side-effects. Hence, it has become crucial to develop a delivery system that could increase efficacy and reduce systemic absorption. Therefore, the present work aims to develop Brimonidine Tartrate gels with different concentrations (0.05%, 0.1%, and 0.2% w/v, respectively) using Carbopol 974 P and HPMC E4M, and compare the therapeutic efficacy and systemic absorption with that of eye drop (0.2%, w/v) by UPLC-MS/MS. The result of histological analysis did not show any morphological or structural changes after the administration of formulations. In vitro residence time studies demonstrated that the gels exhibited a better precorneal residence time as compared with the eye drop. The gels with lower concentrations of the drug (0.05% and 0.1%, w/v) could significantly decrease intraocular pressure (IOP) in both normal and water-loaded rabbits as compared to the eye drop. Finally, the values of the ratio of AUC(0→∞) in comparison to eye drop showed the gels with lower concentrations of Brimonidine Tartrate could decrease the systemic absorption. From the result, it can be concluded the 0.1% ophthalmic gel has a potential to improve therapeutic efficacy and reduce the potential toxicity caused by systemic absorption.

Toxicity of ZnO nanoparticles (NPs) with or without hydrophobic surface coating to THP-1 macrophages: interactions with BSA or oleate-BSA.

It is recently shown that biological macromolecules in food could interact with nanoparticles (NPs) and consequently change the biological effects of NPs. In this study, the interactions between ZnO NPs with or without hydrophobic surface coating and bovine serum albumin (BSA) or oleate (OA) complexed to BSA (OA-BSA) were assessed. Atomic force microscope (AFM) showed topographic changes of both types of NPs by BSA or OA-BSA, which could indicate the formation of protein corona. ZnO NPs showed negative Zeta potential, which was slightly decreased by BSA or OA-BSA, with OA-BSA being more effective. The UV-Vis was increased, whereas the fluorescence and synchronous fluorescence was decreased by the presence of ZnO NPs. Exposure to both types of ZnO NPs was associated with cytotoxicity to THP-1 macrophages, which was equally mitigated by BSA or OA-BSA associated with decreased cellular Zn elements. Exposure to ZnO NPs was associated with decreased release of cytokines, which was not affected by BSA or OA-BSA. In combination, the results from this study suggested that both BSA and OA-BSA could be adsorbed to ZnO NPs regardless of hydrophobic surface coating, which reduced the cytotoxicity of NPs to macrophages probably due to reduced association between NPs and cells. BSA and OA-BSA equally protected THP-1 macrophages from ZnO NP exposure, which might indicate that complexation to OA did not compromise the cytoprotective effects of BSA. These data might also indicate the complex interaction between NPs and biological macromolecules as food components, which should be considered for future nanotoxicological studies.

Physiologically Based Absorption Modeling of Salts of Weak Bases Based on Data in Hypochlorhydric and Achlorhydric Biorelevant Media.

Physiologically based absorption modeling has been attracting increased attention to study the interactions of weakly basic drug compounds with acid-reducing agents like proton-pump inhibitors and H2 blockers. Recently, standardized gastric and intestinal biorelevant media to simulate the achlorhydric and hypochlorhydric stomach were proposed and solubility and dissolution data for two model compounds were generated. In the current manuscript, for the first time, we report the utility of these recently proposed biorelevant media as input into physiologically based absorption modeling. Where needed, data collected with the biorelevant gastrointestinal transfer (BioGIT) system were used for informing the simulations in regard to the precipitation kinetics. Using two model compounds, a HCl salt and a semi-fumarate co-crystal which as expected dissolve to a greater extent in these media (and in gastric and intestinal human aspirates) compared to what the pH-solubility profile of the free form would suggest, we demonstrate successful description of the plasma concentration profiles and correctly predicted the lack of significant interaction after administration with pantoprazole or famotidine, respectively. Thus, the data reported in this manuscript represent an initial step towards defining biorelevant input for such simulations on interactions with acid-reducing agents.

Deubiquitylase Inhibition Reveals Liver X Receptor-independent Transcriptional Regulation of the E3 Ubiquitin Ligase IDOL and Lipoprotein Uptake.

Cholesterol metabolism is subject to complex transcriptional and nontranscriptional regulation. Herein, the role of ubiquitylation is emerging as an important post-translational modification that regulates cholesterol synthesis and uptake. Similar to other post-translational modifications, ubiquitylation is reversible in a process dependent on activity of deubiquitylating enzymes (DUBs). Yet whether these play a role in cholesterol metabolism is largely unknown. As a first step to test this possibility, we used pharmacological inhibition of cellular DUB activity. Short term (2 h) inhibition of DUBs resulted in accumulation of high molecular weight ubiquitylated proteins. This was accompanied by a dramatic decrease in abundance of the LDLR and attenuated LDL uptake into hepatic cells. Importantly, this occurred in the absence of changes in the mRNA levels of the LDLR or other SREBP2-regulated genes, in line with this phenotype being a post-transcriptional event. Mechanistically, we identify transcriptional induction of the E3 ubiquitin ligase IDOL in human and rodent cells as the underlying cause for ubiquitylation-dependent lysosomal degradation of the LDLR following DUB inhibition. In contrast to the established transcriptional regulation of IDOL by the sterol-responsive liver X receptor (LXR) transcription factors, induction of IDOL by DUB inhibition is LXR-independent and occurs in Lxrαß(-/-) MEFs. Consistent with the role of DUBs in transcriptional regulation, we identified a 70-bp region in the proximal promoter of IDOL, distinct from that containing the LXR-responsive element, which mediates the response to DUB inhibition. In conclusion, we identify a sterol-independent mechanism to regulate IDOL expression and IDOL-mediated lipoprotein receptor degradation.

Gastric and Duodenal Ethanol Concentrations after Intake of Alcoholic Beverages in Postprandial Conditions.

This study determined intraluminal ethanol concentrations (stomach and duodenum) in fed healthy volunteers after the consumption of common alcoholic beverages (beer, wine, and whisky). The results of this study were compared with a previous study in fasted volunteers. Five healthy volunteers were recruited in a crossover study. The fed state was simulated by ingestion of 250 mL of Nutridrink Compact Neutral. Volunteers subsequently consumed two standard units of beer (Stella Artois, 500 mL, 5.2% ethanol), wine (Blanc du Blanc, 200 mL, 11% ethanol), or whisky (Gallantry Whisky, 80 mL, 40% ethanol). Gastric and duodenal fluids were aspirated through two catheters over time and analyzed for ethanol content by head space gas chromatography. The capability of ethanol to permeate gastric and duodenal rat mucosa was examined in an Ussing chambers setup. A similar average gastric Cmax was observed in the beer and the wine conditions: 3.3% and 3.7% ethanol, respectively. The gastric Cmax in the whisky condition amounted to 8.5% ethanol. Lower ethanol concentrations were observed in the duodenum compared to the stomach. The duodenal Cmax was similar in all three conditions: 1.3%, 1.2%, and 1.6% ethanol for beer, wine, and whisky, respectively. Compared to the fasted state (reported in a previous study), higher gastric ethanol concentrations were observed during a longer time period. In the beer and wine conditions, similar concentrations were observed in the intestine regardless of the prandial state. After intake of whisky, however, the ethanol concentration was lower in the fed intestine. Alcohol was observed to permeate both gastric and duodenal rat mucosa. Higher intragastric ethanol concentrations were maintained for a longer period of time in fed compared to fasted state conditions. However, the observed concentration profiles were not in line with current FDA guidelines for alcohol resistance testing of formulations, stating that in vitro tests should investigate the impact of up to 40% ethanol for 2 h. The presented intraluminal ethanol concentrations may serve as reference data for the further development of relevant in vitro models to assess ethanol effects on formulation performance.

Inhibition of NF-κB activation improves insulin resistance of L6 cells.

To explore the role of NF-κB activation in the development of insulin resistance and investigate whether or not that the inhibition of NF-κB activation by PDTC will improve the insulin resistance of L6 cells exposed to H2O2. L6 cells were treated with H2O2, PDTC or both H2O2 and PDTC for 4 hours. The uptake of glucose with stimulation of insulin, the expression of P38-MAPK, p- P38-MAPK, NF-κBp65, p- NF-κBp65, IRS-1, IRS-2, p-IRS-2, PI3K, IκBα, p- IκBα, caspase-8 and GLUT4, the production of ROS, TNF-α, IL-6 and IL-1ß as well as the apoptosis rate of L6 cells were determined and compared in L6 treated with H2O2 alone or both H2O2 and PDTC. Compared with the L6 cells treated with H2O2 alone, the L6 cells treated with both H2O2 and PDTC showed (1) significantly lower production of ROS, TNF-α, IL-6 and IL-1ß; (2) significantly decreased expression of P38-MAPK, p- P38-MAPK and NF-κBp65, p- NF-κBp65, p- IκBα and caspase-8; (3) significantly lower rate of apoptosis; (4) significantly higher expression of IRS-2, p-IRS-2 (Tyr 612), PI3K and GLUT4; (5) significantly higher uptake of glucose with stimulation of insulin; (6) significantly increased expression of Bcl2 and decreased ratio of Bax to Bcl2. Based on the findings of the present study, inhibition of NF-κB activation by PDTC would improve the insulin resistance of L6 cells exposed to H2O2.

Up-regulation of abscisic acid signaling pathway facilitates aphid xylem absorption and osmoregulation under drought stress.

The activation of the abscisic acid (ABA) signaling pathway reduces water loss from plants challenged by drought stress. The effect of drought-induced ABA signaling on the defense and nutrition allocation of plants is largely unknown. We postulated that these changes can affect herbivorous insects. We studied the effects of drought on different feeding stages of pea aphids in the wild-type A17 of Medicago truncatula and ABA signaling pathway mutant sta-1. We examined the impact of drought on plant water status, induced plant defense signaling via the abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA) pathways, and on the host nutritional quality in terms of leaf free amino acid content. During the penetration phase of aphid feeding, drought decreased epidermis/mesophyll resistance but increased mesophyll/phloem resistance of A17 but not sta-1 plants. Quantification of transcripts associated with ABA, JA and SA signaling indicated that the drought-induced up-regulation of ABA signaling decreased the SA-dependent defense but increased the JA-dependent defense in A17 plants. During the phloem-feeding phase, drought had little effect on the amino acid concentrations and the associated aphid phloem-feeding parameters in both plant genotypes. In the xylem absorption stage, drought decreased xylem absorption time of aphids in both genotypes because of decreased water potential. Nevertheless, the activation of the ABA signaling pathway increased water-use efficiency of A17 plants by decreasing the stomatal aperture and transpiration rate. In contrast, the water potential of sta-1 plants (unable to close stomata) was too low to support xylem absorption activity of aphids; the aphids on sta-1 plants had the highest hemolymph osmolarity and lowest abundance under drought conditions. Taken together this study illustrates the significance of cross-talk between biotic-abiotic signaling pathways in plant-aphid interaction, and reveals the mechanisms leading to alter aphid fecundity in water stresses plants.

Lidocaine Concentration in Oral Tissue by the Addition of Epinephrine.

The vasoconstrictive effect due to the addition of epinephrine to local anesthetic has been clearly shown by measuring blood-flow volume or blood anesthetic concentration in oral mucosal tissue. However, there are no reports on the measurement of anesthetic concentration using samples directly taken from the jawbone and oral mucosal tissue. Consequently, in this study, the effect of lidocaine concentration in the jawbone and oral mucosal tissue by the addition of epinephrine to the local anesthetic lidocaine was considered by quantitatively measuring lidocaine concentration within the tissue. Japanese white male rabbits (n = 96) were used as test animals. General anesthesia was induced by sevoflurane and oxygen, and then cannulation to the femoral artery was performed while arterial pressure was constantly recorded. Infiltration anesthesia was achieved by 0.5 mL of 2% lidocaine containing 1 : 80,000 epinephrine in the upper jawbone (E(+)) and 0.5 mL of 2% of epinephrine additive-free lidocaine (E(0)) under the periosteum. At specified time increments (10, 20, 30, 40, 50, and 60 minutes), samples from the jawbone, oral mucosa, and blood were collected, and lidocaine concentration was directly measured by high-performance liquid chromatography. No significant differences in the change in blood pressure were observed either in E(+) or E(0). In both E(+) and E(0) groups, the serum lidocaine concentration peaked 10 minutes after local anesthesia and decreased thereafter. At all time increments, serum lidocaine concentration in E(+) was significantly lower than that in E(0). There were no significant differences in measured lidocaine concentration between jawbone and mucosa within either the E(+) or the E(0) groups at all time points, although the E(0) group had significantly lower jawbone and mucosa concentrations than the E(+) group at all time points when comparing the 2 groups to each other. Addition of epinephrine to the local anesthetic inhibited systemic absorption of local anesthetic into the blood such that a high concentration could be maintained in the tissue. Epinephrine-induced vasoconstrictive effect was observed not only in the oral mucosa but also in the jawbone.

Base to Tip and Long-Distance Transport of Sodium in the Root of Common Reed [Phragmites australis (Cav.) Trin. ex Steud.] at Steady State Under Constant High-Salt Conditions.

We analyzed the directions and rates of translocation of sodium ions (Na(+)) within tissues of a salt-tolerant plant, common reed [Phragmites australis (Cav.) Trin. ex Steud.], and a salt-sensitive plant, rice (Oryza sativa L.), under constant high-salt conditions using radioactive (22)Na tracer and a positron-emitting tracer imaging system (PETIS). First, the test plants were incubated in a nutrient solution containing 50 mM NaCl and a trace level of (22)Na for 24 h (feeding step). Then the original solution was replaced with a fresh solution containing 50 mM NaCl but no (22)Na, in which the test plants remained for >48 h (chase step). Non-invasive dynamic visualization of (22)Na distribution in the test plants was conducted during feeding and chase steps with PETIS. Our results revealed that (22)Na was absorbed in the roots of common reed, but not transported to the upper shoot beyond the shoot base. During the chase step, a basal to distal movement of (22)Na was detected within the root tissue over >5 cm with a velocity of approximately 0.5 cm h(-1). On the other hand, (22)Na that was absorbed in the roots of rice was continuously translocated to and accumulated in the whole shoot. We concluded that the basal roots and the shoot base of common reed have constitutive functions of Na(+) exclusion only in the direction of root tips, even under constant high-salt conditions. This function apparently may contribute to the low Na(+) concentration in the upper shoot and high salt tolerance of common reed.

Prostanoid receptors EP2, EP4, and FP are regulated by estradiol in bovine oviductal smooth muscle.

Gamete and embryo transport is an important function of the oviduct. This transport involves both smooth muscle contraction and epithelial cell secretions, the former of which is mediated by prostaglandins (PGs) and their receptors. Our aim was to study the regulation of prostaglandin E2 and prostaglandin F2α receptors (EP2, EP4, and FP receptor) by estradiol in bovine oviduct smooth muscle. EP2, EP4, and FP receptor mRNA and protein expression was investigated using real-time RT-PCR and Western blot analyses, respectively. To evaluate the contraction or relaxation of cultured bovine oviductal smooth muscle tissue, peristalsis was used to assess contractile activity. EP2, EP4, and FP receptor mRNA and protein expression was increased in oviductal smooth muscle tissue after treatment with different concentrations of estradiol for various durations. The expression of all receptors peaked at an estradiol concentration of 10(-11)mol/L after 8h of treatment, whereas no increase in expression was observed after fulvestrant (a selective antagonist of E2 receptor) treatment, indicating that E2 interacts with specific E2 nuclear receptors to regulate EP2, EP4, and FP receptor expression. Although PGF2α and PGE2 induced both contraction and relaxation, no significant differences were found in contractility between the estradiol-treated and control groups, with both groups of cultured smooth muscle strips showing similar vitality. In conclusion, estradiol increases EP2, EP4, and FP receptor mRNA and protein expression in bovine oviductal smooth muscle when added for different periods of time and at different concentrations. Additionally, E2 is transported intracellularly and interacts with specific E2 nuclear receptors to regulate their expression.