Targeting of Antisense: Synthesis of Steroid-Linked and Steroid-Bridged Oligodeoxynucleotides

Estimation of drug-likeness properties of GC-MS separated bioactive compounds in rare medicinal Pleione maculata using molecular docking technique and SwissADME in silico tools

The main aim of the paper was to determine bioactive compounds in Pleione maculata extracts using gas chromatographic technique and to investigate their drug-likeness potential using molecular docking algorithm and ADME studies on the recent intractable disease, for example, SARS-CoV-2. Pleione maculata sample was prepared for GC–MS analysis. The peak components were identified based on the NIST Library. Molecular docking was performed using PatchDock, and energy refinement was carried out using the FireDock algorithm followed by drug-likeness analysis using the SwissADME tool. The mass spectrum revealed various pharmacologically important compounds and novel compounds 8-oxatetracyclo{5.2.1.1(2,6). 1(4,10)}dodecane, 7-tert-butyl-1,9,9-trimeth, docosane, 2,4-dimethyl, kryptogenin 2,4-dinitrophenyl hydrazine, and N-decyl-alpha,D-2-deoxyglycoside which are reported for the first time. Molecular docking using PatchDock illustrates GC–MS compounds Nor-diazepam,3-{N-hydroxymethyl}aminocarbonyloxy a good docking and high binding affinity with atomic contact energy -10.95 kcal/mol against SARS-CoV-2 spike protein S2 subunit. ADME analysis predicts Nor-diazepam,3-{N-hydroxymethyl}aminocarbonyloxy and andrographolide showed very high drug-likeness parameters with no metabolism disturbances. The random control antiviral drug arabidiol revealed a lower binding affinity and lower solubility compared to bioactive compounds of P. maculata. The study depicts the first and novel report on various pharmaceutical important GC–MS bioactive compounds and molecular docking study on Pleione maculata having potential against various intractable diseases.

Cationic corticosteroid for nonviral gene delivery

Delivery of plasmid DNA for gene therapy often provokes an inflammatory response that reduces transgene expression. Cationic lipids for lipofection lack pharmacological activity despite the hydrophobicity of many drug candidates that could be exploited. We report a one-step synthesis of a water-soluble, dexamethasone-spermine (DS) cationic lipid that has potent gene transfer capability in confluent endothelial cells when used with the neutral lipid, dioleoylphosphatidylethanolamine (DOPE). In contrast, unconjugated mixtures of dexamethasone, spermine, and/or DOPE have essentially no gene transfer activity. DS retains partial corticosteroid character as quantified by the rapid translocation of glucocorticoid receptor to the nucleus and by dose-dependent transactivation from a glucocorticoid response element. DS has anti-inflammatory activity in vivo in the mouse thioglycollate model of inflammation. In a mouse lung model, DS:DOPE resulted in significantly less interferon-gamma production at Day 1 and elevated transgene expression at Days 1 and 7 postintranasal instillation compared to DC-Chol:DOPE (sterol:DOPE:phosphate molar ratio of 1:1:1). Cationic pharmacophores such as DS represent a new approach to gene delivery and localized therapy.

Discovering antisense reagents by hybridization of RNA to oligonucleotide arrays

Antisense reagents have the potential to modify gene expression by interacting with DNA or mRNA to down-regulate transcription or translation. There have been a number of successful demonstrations of antisense activity in vivo. However, a number of problems must be solved before the method's full potential can be realized. One problem is the need for the antisense agent to form a duplex with the target molecule. We have found that most regions of mRNAs are not open to duplex formation with oligonucleotides because the bases needed for Watson-Crick base pairing are involved in intramolecular pairing. Using arrays of oligonucleotides that are complementary to extensive regions of the mRNA target, we are able to find those antisense oligonucleotides which bind optimally. There is good correspondence between the ability of an oligonucleotide to bind to its target and its activity as an antisense agent in in vivo and in vitro tests. To understand more fully the rules governing the process of duplex formation between a native RNA and complementary oligonucleotides, we have studied the interactions between tRNAphe and a complete set of complementary dodecanucleotides. Only four of the set of 65 oligonucleotides interact strongly. The four corresponding regions in the tRNA share structural features. However, other regions with similar features do not form a duplex. It is clear that ab initio prediction of patterns of interaction require much greater knowledge of the process of duplex formation than is presently available.