Induction of gene pattern changes associated with dysfunctional lipid metabolism induced by dietary fat and exposure to a persistent organic pollutant

Environmental modulators of chronic diseases can include nutrition, lifestyle, as well as exposure to environmental toxicants such as persistent organic pollutants. A study was designed to explore gene expression changes as affected by both dietary fat and exposure to the polychlorinated biphenyl PCB77. Mice were fed for 4 months diets enriched with high-linoleic acid oils (20% and 40% as calories), and during the last 2 months half of each group was exposed to PCB77. Ribonucleic acids (RNA) were extracted from liver tissue to determine gene expression changes using DNA microarray analysis. Our microarray data demonstrated a significant interaction between dietary fat and PCB exposure. Deregulated genes were organized into patterns describing the interaction of diet and PCB exposure. Annotation of the deregulated genes matching these probe sets revealed a significant high-fat mediated induction of genes associated with fatty acid metabolism, triacylglycerol synthesis and cholesterol catabolism, which was down-regulated in animals exposed to PCB77. Many of these genes are regulated by the peroxisome proliferator activated receptor-α (PPARα), and changes in PPARα gene expression followed the same gene pattern as described above. These results provide insight into molecular mechanisms of how dietary fat can interact with environmental pollutants to compromise lipid metabolism.     

N-type and P/Q-type calcium channels regulate differentially the release of noradrenaline, ATP and beta-NAD in blood vessels

Using HPLC techniques we evaluated the electrical field stimulation-evoked overflow of noradrenaline (NA), adenosine 5'-triphosphate (ATP), and beta-nicotinamide adenine dinucleotide (beta-NAD) in the presence of low nanomolar concentrations of omega-conotoxin GVIA or omega-agatoxin IVA in the canine mesenteric arteries and veins. omega-conotoxin GVIA abolished the evoked overflow of NA and beta-NAD in artery and vein, whereas the evoked overflow of ATP remained unchanged in the presence of omega-conotoxin GVIA. omega-agatoxin IVA significantly reduced the evoked overflow of ATP and beta-NAD. The overflow of NA remained largely unaffected by omega-agatoxin IVA, except at 16Hz in the vein where the overflow of NA was reduced by about 50%. Artery and vein exhibited similar expression levels of the alpha(1B) (CaV2.2, N-type) subunit, whereas the vein showed greater levels of the alpha(1A) (CaV2.1, P/Q-type) subunit than artery. Therefore, there are at least two release sites for NA, beta-NAD and ATP in the canine mesenteric artery and vein: an N-type-associated site releasing primarily NA, beta-NAD and some ATP, and a P/Q-type-associated site releasing ATP, beta-NAD and some NA. The N-type-mediated mechanisms are equally expressed in artery and vein, whereas the P/Q-type-mediated mechanisms are more pronounced in the vein and may ensure additional neurotransmitter release at higher levels of neural activity. In artery, beta-NAD caused a dual effect consisting of vasodilatation or vasoconstriction depending on concentrations, whereas vein responded with vasodilatation only. In contrast, ATP caused vasoconstriction in both vessels. beta-NAD and ATP may mediate disparate functions in the canine mesenteric resistive and capacitative circulations.     

Improving potencies and properties of CD4 down-modulating CADA analogs

INTRODUCTION: CADA is a synthetic small molecule that inhibits HIV replication in cell cultures through down-modulating cell surface CD4 by inhibiting cotranslational translocation of nascent CD4 across the ER membrane in a signal sequence-specific manner. Analogs have been prepared mainly to increase potency and investigate the mechanism of action. AREAS COVERED: This article reviews progress on discovery of more potent CADA analogs, including symmetrical and unsymmetrical compounds, as well as fluorescent derivatives. The article also discusses some properties of CADA and a more potent analog (KKD023) that are relevant to drug development, including aqueous solubility, permeability, metabolism and oral bioavailability. EXPERT OPINION: Further studies on CADA analogs should focus on improving both potency and drug-like properties, and on elucidating the detailed mechanism of action. Solubility and permeability may be improved by reducing molecular weight, decreasing molecular flexibility and symmetry, or by a prodrug approach inducing active transport. Identifying the molecular mechanism of CD4 down-modulation may aid in assessing potential side effects of such immunomodulatory/anti-HIV drugs, and it could potentially lead to a general approach to designing drugs for specifically down-modulating other cell-surface proteins.     

LTBP2 and CYP1B1 mutations and associated ocular phenotypes in the Roma/Gypsy founder population

Primary congenital glaucoma (PCG) is a genetically heterogeneous autosomal recessive disorder, which is an important cause of blindness in childhood. The first known gene, CYP1B1, accounts for a variable proportion of cases in most populations. A second gene, LTBP2, was recently reported in association with a syndrome, in which glaucoma is secondary to lens dislocation. We report on the molecular and clinical profile of 34 families diagnosed as PCG, all originating from the Roma/Gypsy founder population. Comprehensive sequencing analysis revealed a level of heterogeneity unusual for this population, with five CYP1B1 and one ancestral LTBP2 mutation accounting for ～70% of patients (25 out of 37) and the remainder still unexplained. Homozygosity for the founder LTBP2 p.R299X mutation resulted in a more severe clinical phenotype and poorer outcome despite a markedly higher number of surgical interventions. The genetically homogeneous group of p.R299X homozygotes showed variable phenotypes (presumably also underlying pathogenetic mechanisms), wherein PCG proper with primary dysgenesis of the trabecular meshwork, and Marfan syndrome-like zonular disease with ectopia lentis and later onset secondary glaucoma are two extremes. The spectrum manifestations may occur in different combinations and have a different evolution even within the same sibship or a single patient. Preliminary observations on compounds with mutations in both CYP1B1-LTBP2 suggest that the observed combinations are of no clinical significance and digenic inheritance is unlikely. We provide a population genetics perspective to explain the allelic heterogeneity, comparing the history and geographic distribution of the two major founder mutations--p.R299X/LTBP2 and p.E387K/CYP1B1.     

Can natural antibodies to VIP or VIP-like HIV-1 glycoprotein facilitate prevention and supportive treatment of breast cancer?

Objectives

The incidence of non-AIDS-defining cancer is remarkably higher in HIV-infected than in the general population. In contrast, breast cancer risk is significantly reduced in the HIV-infected population. The molecular mechanisms underlying the phenomenon of suppression of breast cancer in the HIV-infected population may serve as a basis for development of a new platform for prevention and treatment of breast cancer.

Hypothesis

Various evidences indicate that vasoactive intestinal peptide (VIP) plays an important role in growth, and differentiation of breast cancer. We previously showed (i) that natural antibodies recognizing VIP and the gp120-derived peptide NTM significantly contribute to the control of HIV disease progression by suppression of VIP-like activity of HIV-1 gp120 and (ii) that physical exercise stimulates production of these natural antibodies. These findings suggest that natural anti-VIP/NTM antibodies could contribute to a decrease of breast cancer in the HIV-infected population by suppression of VIP, which may play a pro/oncogenic function. Aerobic exercise which stimulates production of anti-VIP/NTM antibodies could be used as prevention and supportive treatment of breast cancer.

Impact

Immunotherapy based on natural anti-VIP/NTM antibodies could serve as an effective adjunct therapy for the treatment of breast cancer. Similarly, aerobic exercise, which stimulates production of these antibodies, should be considered as an inexpensive and safe preventive and supportive breast cancer therapy. Natural anti-VIP/NTM antibodies also represent promising prognostic marker for breast cancer.     

Gelatin-siloxane hybrid scaffolds with vascular endothelial growth factor induces brain tissue regeneration

In the brain after infarction or trauma, the tissue becomes pannecrotic and forms a cavity. In such situation, a scaffold is necessary to produce new tissue. In this study, we implanted a new porous gelatin-siloxane hybrid derived from gelatin and 3-(glycidoxypropyl) trimethoxysilane (gelatin-GPTMS) scaffolds into a brain defect, and investigated whether it makes a new brain tissue. In addition, vascular endothelial growth factor (VEGF) was added on gelatin-GPTMS scaffolds and its effect on tissue regeneration was examined. At 30 days after the implantation, the marginal territory of the scaffolds became occupied by newly formed tissue. Immunohistochemical analysis revealed that the new tissue was constituted by endothelial, astroglial and microglial cells, some of which were labeled for bromodeoxyuridine (BrdU). Addition of VEGF promoted numbers of these cells. Thus, combination of gelatin-GPTMS scaffolds and VEGF is preferable for brain regeneration.     

The Use of Early and Midpoint Adenoma-Carcinoma Sequence Biomarkers in Prediction of Neoplastic Progression in Patients with a History of Colorectal Neoplasia

Since significant neoplasia after initial colonoscopy is low, we conducted this pilot study to compare the predictive role for colorectal neoplasia recurrence of anti-DCC with that of Adnab-9 binding to colonic effluent of high-risk patients. DCC and Adnab-9 effluent ELISA were performed at baseline colonoscopies. The results of follow-up colonoscopies were reviewed. To ensure specificity, immunohistochemistry and Western blot was performed with anti-DCC and for Adnab-9 where optimal fixation times were also evaluated. Mean follow-up was 2.6 years. Of 21 patients, 6 of 10 who progressed to CRN and 2 of 11 who did not had a positive Adnab-9 ELISA result (P=0.08). Despite an initial good correlation with Adnab-9 ELISA results in a smaller dataset, we were unable to obtain consistent subsequent DCC immunohistochemistry or Western blot data using antibody from two different sources. However, the original dataset of Adnab-9 results was reproducible on repetition of the ELISA with a larger set of samples that included this initial dataset and optimal fixation time was 20 min. We conclude that Adnab-9 appears to be a promising prognostic marker for neoplasia in the high-risk population. Industry standards need to be developed for DCC monoclonal antibodies that may have similar utility.     

Alpha-enolase: a novel autoantigen in patients with premature ovarian failure

OBJECTIVE: Although controversial, the presence of circulating antiovarian antibodies (AOA) may be considered a marker of autoimmune premature ovarian failure (POF). The purpose of the present work was to evaluate the presence of AOA in POF patients, and to identify a possible autoantigen in order to develop a reliable diagnostic tool that might help to determine the real prevalence of autoimmune POF. DESIGN: Non-randomised study. Blood sampling for determination of circulating AOA. PATIENTS: One hundred and ten patients with POF and 60 normally menstruating women with no record of autoimmune diseases (controls). MEASUREMENTS: Presence of circulating AOA was assessed by Western-blot, using cytosolic fraction from human ovarian homogenate as antigen. RESULTS: Twenty-one of 110 women with POF presented circulating antibodies directed toward an antigen of approximately 50 kD. Sixty control subjects proved negative. After purification and analysis by mass spectrometry, the antigen was identified as alpha-enolase. CONCLUSION: Determination of the presence of circulating antialpha-enolase antibodies might be instrumental in identifying those patients who may present a putative defect in immunoregulation and therefore a possible autoimmune aetiolgy for POF.