Developmental exposure to the A6-pesticide causes changes in tyrosine hydroxylase gene expression, neurochemistry, and locomotors behavior in larval zebrafish.

In recent years, the increase in the biopesticides synthesis for alternative agricultural uses has required their impacts study. Among these compounds, several of them are known to exert endocrinedisrupting (EDs) effects causing deregulation of physiological functions affecting cell signaling pathways involved in neural cell differentiation leading to developmental neurotoxicity. The objective of our study was to determine the impact of the biopesticide A6 structurally related to estrogenic EDs on zebrafish larvae, to define its toxicity, the mechanisms responsible, and to monitor the locomotors activity at nanomolar concentrations (0.

Ethinylestradiol (EE2) residues from birth control pills impair nervous system development and swimming behavior of zebrafish larvae.

The ubiquitous use of ethinylestradiol (EE2), an active constituent of birth control preparations, results in continuous release of this synthetic estrogen to surface waters. Many studies document the untoward effects of EE2 on the endocrine system of aquatic organisms. Effects of environmental EE2 on the nervous system are still poorly documented.

Variant-specific discrepancy when quantitating BCR-ABL1 e13a2 and e14a2 transcripts using the Europe Against Cancer qPCR assay.

Objective: Molecular monitoring of treatment response in patients with chronic myelogenous leukemia is performed using the Europe Against Cancer (EAC) qPCR assay using the International Scale (IS). The assay amplifies both e13a2 and e14a2 BCR-ABL1 transcript variants. Observing distinct variant-dependent amplification curves during qPCR, we aimed to determine if this affected quantitation of BCR-ABL1.

In mammalian foetal testes, SOX9 regulates expression of its target genes by binding to genomic regions with conserved signatures.

In mammalian embryonic gonads, SOX9 is required for the determination of Sertoli cells that orchestrate testis morphogenesis. To identify genetic networks directly regulated by SOX9, we combined analysis of SOX9-bound chromatin regions from murine and bovine foetal testes with sequencing of RNA samples from mouse testes lacking Sox9. We found that SOX9 controls a conserved genetic programme that involves most of the sex-determining genes.

Neurotoxicity of a Biopesticide Analog on Zebrafish Larvae at Nanomolar Concentrations.

Despite the ever-increasing role of pesticides in modern agriculture, their deleterious effects are still underexplored. Here we examine the effect of A6, a pesticide derived from the naturally-occurring α-terthienyl, and structurally related to the endocrine disrupting pesticides anilinopyrimidines, on living zebrafish larvae. We show that both A6 and an anilinopyrimidine, cyprodinyl, decrease larval survival and affect central neurons at micromolar concentrations.

Intestinal epithelial stem cells do not protect their genome by asymmetric chromosome segregation.

The idea that stem cells of adult tissues with high turnover are protected from DNA replication-induced mutations by maintaining the same 'immortal' template DNA strands together through successive divisions has been tested in several tissues. In the epithelium of the small intestine, the provided evidence was based on the assumption that stem cells are located above Paneth cells. The results of genetic lineage-tracing experiments point instead to crypt base columnar cells intercalated between Paneth cells as bona fide stem cells.

A 20-amino acid module of protein kinase C{epsilon} involved in translocation and selective targeting at cell-cell contacts.

In the pituitary gland, activated protein kinase C (PKC) isoforms accumulate either selectively at the cell-cell contact (alpha and epsilon) or at the entire plasma membrane (beta1 and delta). The molecular mechanisms underlying these various subcellular locations are not known. Here, we demonstrate the existence within PKCepsilon of a cell-cell contact targeting sequence (3CTS) that, upon stimulation, is capable of targeting PKCdelta, chimerin-alpha1, and the PKCepsilon C1 domain to the cell-cell contact.

Delivery of steric block morpholino oligomers by (R-X-R)4 peptides: structure-activity studies.

Redirecting the splicing machinery through the hybridization of high affinity, RNase H- incompetent oligonucleotide analogs such as phosphoramidate morpholino oligonucleotides (PMO) might lead to important clinical applications. Chemical conjugation of PMO to arginine-rich cell penetrating peptides (CPP) such as (R-Ahx-R)(4) (with Ahx standing for 6-aminohexanoic acid) leads to sequence-specific splicing correction in the absence of endosomolytic agents in cell culture at variance with most conventional CPPs. Importantly, (R-Ahx-R)(4)-PMO conjugates are effective in mouse models of various viral infections and Duchenne muscular dystrophy.

Lipoplex and peptide-based strategies for the delivery of steric-block oligonucleotides.

Synthetic oligonucleotides offer interesting prospects for the control of gene expression but clinical applications have been severely limited by their poor bioavailability. Cationic lipids have been widely used for the delivery of charged oligonucleotide (ON) analogues but most of the commercial formulations are toxic and poorly stable in the presence of serum proteins. We have developed a DOGS/DOPE liposome formulation named DLS (for delivery liposomal system), that allows for the efficient nuclear delivery of negatively charged antisense ON analogues as monitored by fluorescence microscopy and by their ability to correct deficient pre-mRNA splicing, even in serum-supplemented cell culture.

Efficient splicing correction by PNA conjugation to an R6-Penetratin delivery peptide.

Sequence-specific interference with the nuclear pre-mRNA splicing machinery has received increased attention as an analytical tool and for development of therapeutics. It requires sequence-specific and high affinity binding of RNaseH-incompetent DNA mimics to pre-mRNA. Peptide nucleic acids (PNA) or phosphoramidate morpholino oligonucleotides (PMO) are particularly suited as steric block oligonucleotides in this respect.

Chemical modifications to improve the cellular uptake of oligonucleotides.

Specific control of gene expression by synthetic oligonucleotides (ON) is now widely used for target validation but clinical applications are limited by ON bioavailability. Moreover, most currently used strategies for physical and chemical delivery cannot be easily implemented in vivo. This article reviews new strategies which appear promising for ON delivery.

Vectorization of morpholino oligomers by the (R-Ahx-R)4 peptide allows efficient splicing correction in the absence of endosomolytic agents.

The efficient and non-toxic nuclear delivery of steric-block oligonucleotides (ON) is a prerequisite for therapeutic strategies involving splice correction or exon skipping. Cationic cell penetrating peptides (CPPs) have given rise to much interest for the intracellular delivery of biomolecules, but their efficiency in promoting cytoplasmic or nuclear delivery of oligonucleotides has been hampered by endocytic sequestration and subsequent degradation of most internalized material in endocytic compartments. In the present study, we compared the splice correction activity of three different CPPs conjugated to PMO(705), a steric-block ON targeted against the mutated splicing site of human beta-globin pre-mRNA in the HeLa pLuc705 splice correction model.

Improved brain uptake and pharmacological activity profile of morphine-6-glucuronide using a peptide vector-mediated strategy.

Morphine-6-glucuronide (M6G), an active metabolite of morphine, has been shown to have significantly attenuated brain penetration relative to that of morphine. Recently, we have demonstrated that conjugation of various drugs to peptide vectors significantly enhances their brain uptake. In this study, we have conjugated morphine-6-glucuronide to a peptide vector SynB3 to enhance its brain uptake and its analgesic potency after systemic administration.

Peptide-vector strategy bypasses P-glycoprotein efflux, and enhances brain transport and solubility of paclitaxel.

We present the results obtained with paclitaxel coupled to a peptide-vector SynB3 (PAX-OSUC-SynB3), showing that this peptide-vector enhances the solubility of paclitaxel and its brain uptake in mice using the in situ brain perfusion model. We also show by the in situ brain perfusion in P-glycoprotein (P-gp)-deficient and wild-type mice that vectorized paclitaxel bypasses the P-gp present at the luminal side of the blood-brain barrier. The effect of the vectorized paclitaxel on various cancer cells was not significantly different from that of free paclitaxel.

2-Pyrrolinodoxorubicin and its peptide-vectorized form bypass multidrug resistance.

A well-known mechanism leading to the emergence of multidrug-resistant tumor cells is the overexpression of P-glycoprotein, which is capable of lowering intracellular drug concentrations. In the present study, we tested the capability of 2-pyrrolinodoxorubicin (p-DOX), a highly potent derivative of DOX, to bypass multidrug resistance. The accumulation, intracellular distribution and cytotoxicity of p-DOX were tested in two cell lines (K562 and A2780) and their DOX-resistant counterparts (K562/ADR and A2780/ADR).

Improved brain uptake and pharmacological activity of dalargin using a peptide-vector-mediated strategy.

The blood-brain barrier restricts the passage of substances into the brain. Neuropeptides, such as enkephalins, cannot be delivered into the brain when given systemically because of this barrier. Therefore, there is a need to develop efficient transport systems to deliver these drugs to the brain.

Induction of antigen-specific CTL responses using antigens conjugated to short peptide vectors.

Linear peptides (SynB vectors) with specific sequence motifs have been identified that are capable of enhancing the transport of a wide range of molecules into cells. These peptide vectors have been used to deliver exogenous peptides and protein Ags across the cell membrane and into the cytoplasm of cells. Specifically, in vitro analysis indicated that these SynB peptides enhanced the uptake of two 9-mer peptide Ags, NP(147-155) and Mtb(250-258) (T cell epitopes of influenza nucleoprotein and Mycobacterium tuberculosis, respectively) and the M.

Improved brain delivery of benzylpenicillin with a peptide-vector-mediated strategy.

Previous studies from our laboratory have demonstrated that the coupling of doxorubicin with SynB1 vector dramatically increases its brain uptake. In the present study, we have evaluated the broad application of this approach using another molecule: benzylpenicillin (B-Pc). We, therefore, have coupled the beta-lactam antibiotic B-Pc with SynB1 and assessed its ability to cross the blood-brain barrier (BBB) using the in situ rat brain perfusion method.