Two glucosyltransferases are involved in detoxification of benzoxazinoids in maize

Benzoxazinoids are major compounds involved in chemical defence in grasses. These toxins are stored in the vacuole as glucosides. Two glucosyltransferases, BX8 and BX9, that catalyse this last step of benzoxazinoid biosynthesis have been isolated via functional cloning. No close relative of these maize genes was found among the known glucosyltransferases. The enzymes display a very high degree of substrate specificity. DIMBOA, the major benzoxazinoid in young maize, is the preferred substrate. Both genes are highly expressed in young maize seedlings, the developmental stage with the highest activity of benzoxazinoid biosynthesis. Bx8 is included in the cluster of DIMBOA biosynthesis genes located on the short arm of chromosome 4. Hence, the gene cluster comprises three different enzymatic functions and a complete set of genes for the biosynthesis of DIBOA glucoside. Bx9 mapped to chromosome 1. Expression of Bx8 and Bx9 in Arabidopsis corroborated the potency of the enzymes in detoxification of their substrates. This capacity might have implications for allelopathic interactions.     

Validation of Heart Failure Events in the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) Participants Assigned to Doxazosin and Chlorthalidone

BACKGROUND: The Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) is a randomized, double-blind, active-controlled trial designed to compare the rate of coronary heart disease events in high-risk hypertensive participants initially randomized to a diuretic (chlorthalidone) versus each of three alternative antihypertensive drugs: alpha-adrenergic blocker (doxazosin), ACE-inhibitor (lisinopril), and calcium-channel blocker (amlodipine). Combined cardiovascular disease risk was significantly increased in the doxazosin arm compared to the chlorthalidone arm (RR 1.25; 95% CI, 1.17-1.33; P <.001), with a doubling of heart failure (fatal, hospitalized, or non-hospitalized but treated) (RR 2.04; 95% CI, 1.79-2.32; P <.001). Questions about heart failure diagnostic criteria led to steps to validate these events further. METHODS AND RESULTS: Baseline characteristics (age, race, sex, blood pressure) did not differ significantly between treatment groups (P <.05) for participants with heart failure events. Post-event pharmacologic management was similar in both groups and generally conformed to accepted heart failure therapy. Central review of a small sample of cases showed high adherence to ALLHAT heart failure criteria. Of 105 participants with quantitative ejection fraction measurements provided, (67% by echocardiogram, 31% by catheterization), 29/46 (63%) from the chlorthalidone group and 41/59 (70%) from the doxazosin group were at or below 40%. Two-year heart failure case-fatalities (22% and 19% in the doxazosin and chlorthalidone groups, respectively) were as expected and did not differ significantly (RR 0.96; 95% CI, 0.67-1.38; P = 0.83). CONCLUSION: Results of the validation process supported findings of increased heart failure in the ALLHAT doxazosin treatment arm compared to the chlorthalidone treatment arm.     

Marathon running alters the DNA base excision repair in human skeletal muscle

Reactive oxygen and nitrogen species generated either as products of aerobic metabolism or as a consequence of environmental mutagens, oxidatively modify DNA. Formamidopyrimidine-DNA glycosylase (Fpg) and endonuclease III (endo III) or their functional mammalian homologues repair 7,8-dihydro-8-oxoguanine (8-oxoG) and damaged pyrimidines, respectively, to curb the deleterious effects of oxidative DNA alterations. A single bout of physical exercise can induce oxidative DNA damage. However, its effect on the activity of repair enzymes is not known. Here we report that the activity of a functional homolog of Fpg, human 8-oxoG DNA glycosylase (hOGG1), is increased significantly, as measured by the excision of 32P labeled damaged oligonucleotide, in human skeletal muscle after a marathon race. The AP site repair enzyme did not change significantly. Despite the large individual differences among the six subjects measured, data suggest that a single-bout of aerobic exercise increases the activity of hOGG1 which is responsible for the excision of 8-oxoG. The up-regulation of DNA repair enzymes might be an important part of the regular exercise induced adaptation process.     

Autosomal dominant polycystic kidney disease: Disrupted pathways and potential therapeutic interventions

Autosomal dominant polycystic kidney disease (ADPKD) is a monogenic inherited renal cystic disease that occurs in different races worldwide. It is characterized by the development of a multitude of renal cysts, which leads to massive enlargement of the kidney and often to renal failure in adulthood. ADPKD is caused by a mutation in PKD1 or PKD2 genes encoding the proteins polycystin-1 and polycystin-2, respectively. Recent studies showed that cyst formation and growth result from deregulation of multiple cellular pathways like proliferation, apoptosis, metabolic processes, cell polarity, and immune defense. In ADPKD, intracellular cyclic adenosine monophosphate (cAMP) promotes cyst enlargement by stimulating cell proliferation and transepithelial fluid secretion. Several interventions affecting many of these defective signaling pathways have been effective in animal models and some are currently being tested in clinical trials. Moreover, the stem cell therapy can improve nephropathies and according to studies were done in this field, can be considered as a hopeful therapeutic approach in future for PKD. This study provides an in-depth review of the relevant molecular pathways associated with the pathogenesis of ADPKD and their implications in development of potential therapeutic strategies.     

Effect of curcumin on glioblastoma cells

Curcumin is a polyphenolic compound derived from Curcumin longa L. There are growing bodies of evidence revealing the antitumor effect of curcumin in different tumors; although the molecular mechanism behind this inhibition in glioblastoma multiform (GBM) still remains unclear. Here we investigated the antitumor activity of nano micelles curcumin compared with erlotinib in U-373 cells in monolayer cell cultures and spheroids models. Furthermore, we characterized affecting cell cycle perturbation, as well as apoptosis induction in GBM cells. The antiproliferative activity of nano micelles curcumin and erlotinib were assessed in monolayer and spheroid models. The influence of the cell cycle and expression levels of nuclear factor κB (NF-κB) and Wnt/β-catenin pathway was checked. Nano micelles curcumin suppressed cell growth in U-373 cells via modulation of Wnt and NF-κB pathways. Moreover, cells developed an early G2/M cell cycle arrest followed by sub-G1 apoptosis and apoptotic bodies formation posttreatment with nano micelles curcumin and erlotinib. In the core signaling pathways of GBM, nano micelles curcumin either significantly influences the NF-κB pathway by decreasing p-65 expression or significantly inhibits the Wnt/β-catenin pathway by declining cyclin D1 expression. In conclusion, we have shown that nano micelles curcumin effectively prevent proliferation, and invasion of GBM cells through perturbation of Wnt/β-catenin and NF-κB pathways, suggesting further investigations on the therapeutic application of this novel anticancer drug in in vivo models.     

Design and Visualization of DNA/RNA Nanostructures from Branched Oligonucleotides Using Blender Software

Russian Journal of Bioorganic Chemistry - Recently, three-dimensional nucleic acid nanostructures have attracted great interest, which have been made available through the DNA origami technique. We...     

Expression of TGF-β3 in isolated fibroblasts from foreskin

Background:

The multifunctional transforming growth factor beta (TGF-β) is a glycoprotein that exists in three isoforms. TGF-β3 expression increases in fetal wound healing and reduces fibronectin and collagen I and III deposition, and also improves the architecture of the neodermis which is a combination of blood vessels and connective tissue during wound healing. Fibroblasts are key cells in the wound healing process. TGF-β3 plays a critical role in scar-free wound healing and fibroblast actions in the wound healing process. The aim of this study was to express the TGF-β3 gene (tgf-b3) in human foreskin fibroblasts (HFF’s).

Methods:

We obtained HFF’s from a newborn and a primary fibroblast culture was prepared. The cells were transfected with TGF-β3-pCMV6-XL5 plasmid DNA by both lipofection and electroporation. Expression of TGF-β3 was measured by enzyme-linked immunosorbent assay (ELISA).

Results:

The highest TGF-β3 expression (8.3-fold greater than control) was obtained by lipofection after 72 hours using 3 µl of transfection reagent. Expression was 1.4-fold greater than control by electroporation.

Conclusions:

In this study, we successfully increased TGF-β3 expression in primary fibroblast cells. In the future, grafting these transfected fibroblasts onto wounds can help the healing process without scarring.Key Words: Fibroblasts, Gene expression, TGF-β3