A series of modified oligonucleotides containing P=S backbone and a six-membered azasugar (6-AZS) were synthesized and tested for their ability to inhibit human immunodeficiency virus (HIV) in vitro without the aid of any transfecting agents. While P=S oligonucleotides with natural nucleotides had little anti-HIV-1 activity, six-membered azasugar nucleotide (6-AZN)-containing P=S oligonucleotides (AZPSON) potently inhibited the HIV-1/SHIV production and syncytium formation in vitro (EC50 = 0.02~0.2 micro M) without cytotoxicity up to 100 micro M. AZPSONs are enzymatically stable over 6 days in culture supernatant. Phosphodiester (P=O) backbone only or mixed backbone (P=O and P=S) oligonucleotides that contain 6-AZN did not exhibit anti-HIV-1 activity. The anti-HIV-1 capacity of AZPSON seems to depend on the number and/or distribution patterns of 6-AZN in the oligonucleotides. The oligomer 2198, most effective for anti-HIV-1 activity among the AZPSONs, was much more effective than ddI or ddC in anti-HIV activity. Particularly noteworthy is that the anti-HIV-1 activity of AZPSON-2198 was better than AZT in the long-lasting efficacy after a single treatment.
Giant Cells ; HIV ; HIV-1 ; Nucleotides ; Oligonucleotides ; Phosphorothioate Oligonucleotides*

OBJECTIVETo determine whether 3'phosphorothioate-modified-2 terminal mismatched primers can turn off DNA polymerization mediated by Exo(+) polymerase.

METHODSTwo-directional primer extension was performed using polymerase with and without 3' exonuclease activity. The effects of unmodified primers and 3' phosphorothioate-modified primers on primer extension were evaluated.

RESULTSExo(-) polymerase yielded products from matched and mismatched primers regardless of their modification. However, 3' phosphorothioate-modified primers with a single base mismatch at -2 position worked similarly to the terminal (-1) mismatched primers in triggering the novelly reported "off-switch" of Exo(+) polymerase.

CONCLUSIONThese data suggested that the "off-switch" can be of enormous application in the diagnosis of single gene diseases and in the association studies by single nucleotide polymorphism screening.

DNA Primers ; chemistry ; genetics ; Exonucleases ; metabolism ; Humans ; Phosphorothioate Oligonucleotides ; chemistry ; genetics ; Polymerase Chain Reaction ; Polymorphism, Single Nucleotide

To search the effective antisense oligonucleotide that inhibit the growth of Herpes simplex virus type 1 (HSV-1), six kinds of phosphorothioate oligodeoxynucleotides (S-ODNs) were synthesized and the antiviral activity was assessed by measuring cytopathic effect in Vero cells infected with HSV-1. Of the three dodecamer S-ODNs, cornplernentary to the translation initiation site of IE2 (AS2) and scrambled S-ODN (AS1) showed more significant antiherpetic activity than AS4 complementary to the IE4. Accordingly, the antiviral effect of dodecamer S-ODN was not specific. In contrast to the no inhibitory effect of sense strand S-ODN of ICP8 (AS6), two S-ODNs complementary to the translation initiation site of ICP8 (AS3) and that of IE1 (AS5) showed potent antiherpetic activity assessed in vitro HSV-1 virus yield assay. Antiherpetic effect of AS3 was decreased in proportion to the addition of AS6. The synthesis of viral protein ICPS and IE1 were inhibited in AS3 and AS5 treated HSV-1 infected Vero cells, respectively. These findings suggest that antiherpetic effect of AS3 is specifically mediated by targeting ICPS. S-ODNs had no effect on Vero cell viability. The data suggest that the 19-mer S-ODNs may be effective in antiviral chemotherapy.
Drug Therapy ; Herpes Simplex* ; Herpesvirus 1, Human ; Oligodeoxyribonucleotides ; Phosphorothioate Oligonucleotides* ; Simplexvirus* ; Vero Cells

To study the pharmacokinetics of cantide, an antisense oligonucleotide, and its metabolites after iv gtt administration in rhesus monkeys, a dual solid phase extraction pretreatment method coupling with non-gel sieving capillary electrophoresis analysis method was used for determination of cantide and its metabolites in plasma and their pharmacokinetic parameters were calculated. The pharmacokinetic behavior of cantide and its metabolites (M1 and M2) after iv gtt administration (8, 16 and 24 mg kg(-1)) in rhesus monkeys were investigated. After iv gtt administration of cantide to rhesus monkeys, cantide in plasma was eliminated rapidly and the terminal elimination half-life (t1/2) was 57.91-77.97 min, the correlation coefficients (r) to the dose of Cmax AUC(o-inf) and AUC(0-t) of the prototype was 0.9918, 0.9568 and 0.9773, respectively. The metabolites of cantide reached the Cmax following cantide immediately and the Cmax of metabolites were lower than that of the prototype. The CL(S) of cantide and its metabolites (M1 and M2) were 1.60-2.19, 5.92-8.58 and 6.07-8.78 mL min(-1) kg(-1), respectively. So, it is concluded that the Cmax of cantide and its metabolites increased with the dose, which is the same as their AUC(0-inf) and AUC(0-t). The CL(S) of metabolites were higher than that of the prototype. The MRT and t1/2 of metabolites in the high dose group increased obviously.
Animals ; Area Under Curve ; Electrophoresis, Capillary ; methods ; Female ; Half-Life ; Infusions, Intravenous ; Macaca mulatta ; Male ; Oligonucleotides, Antisense ; blood ; metabolism ; pharmacokinetics ; Phosphorothioate Oligonucleotides ; blood ; metabolism ; pharmacokinetics ; Solid Phase Extraction

RNA therapeutics inhibit the expression of specific proteins/RNAs by targeting complementary sequences of corresponding genes or encode proteins for the synthesis desired genes to treat genetic diseases. RNA-based therapeutics are categorized as oligonucleotide drugs (antisense oligonucleotides, small interfering RNA, RNA aptamers), and mRNA drugs. The antisense oligonucleotides and small interfering RNA for treatment of genetic diseases have been approved by the FDA in the United States, while RNA aptamers and mRNA drugs are still in clinical trials. Chemical modifications can be applied to RNA drugs, such as pseudouridine modification of mRNA, to reduce immunogenicity and improve the efficacy. The secure and effective delivery systems such as lipid-based nanoparticles, extracellular vesicles, and virus-like particles are under development to address stability, specificity, and safety issues of RNA drugs. This article provides an overview of the specific molecular mechanisms of eleven RNA drugs currently used for treating genetic diseases, and discusses the research progress of chemical modifications and delivery systems of RNA drugs.
Aptamers, Nucleotide ; RNA, Small Interfering/therapeutic use* ; RNA, Messenger ; Oligonucleotides, Antisense/therapeutic use*

The present study was undertaken to investigate the role of glial glutamate transporter-1 (GLT-1) in the brain ischemic tolerance induced by cerebral ischemic preconditioning (CIP) by observing the effect of GLT-1 antisense oligodeoxynucleotides (AS-ODNs) on the neuro-protection of CIP against brain ischemic insult in rats. Wistar rats with permanently occluded bilateral vertebral arteries were randomly assigned to 7 groups: (1) Sham group: the bilateral common carotid arteries (BCCA) were separated, but without occluding the blood flow; (2) CIP group: the BCCA were clamped for 3 min; (3) Brain ischemic insult group: the BCCA were clamped for 8 min; (4) CIP+brain ischemic insult group: 3 min CIP was preformed 2 d prior to 8 min ischemic insult; (5) Double distilled water group: 5 muL double distilled water was injected into the right lateral cerebral ventricle 12 h before, 12 h and 36 h after the BCCA was separated (but without occluding the blood flow), respectively; (6) AS-ODNs group: 5 microL AS-ODNs solution was injected into the right lateral cerebral ventricle 12 h before, 12 h and 36 h after the BCCA was separated (but without occluding the blood flow), respectively. This group was further divided into 9 nmol and 18 nmol subgroups according to the doses of AS-ODNs; (7) AS-ODNs+CIP+brain ischemic insult group: 5 microL AS-ODNs solution was injected into the right lateral cerebral ventricle 12 h before, 12 h and 36 h after CIP, respectively. This group was also further divided into 9 nmol and 18 nmol subgroups according to the doses of AS-ODNs. The other treatments were the same as those in CIP+brain ischemic insult group. The effect of the AS-ODNs on the expression of GLT-1 was assayed by using Western blot analysis. The profile of delayed neuronal death (DND) of pyramidal neurons in the CA1 hippocampus was evaluated by using thionin staining under light microscope by determining the neuronal density (ND) and histological grade (HG). Western blot analysis showed that AS-ODNs injected into the lateral cerebroventricle inhibited the expression of GLT-1 in the CA1 hippocampus in a dose-dependent manner. Neuropathological evaluation showed that there was no apparent DND in sham and CIP groups. Obvious DND of pyramidal neurons was found in brain ischemic insult group, which was represented by an increase in HG and a decrease in ND. CIP effectively protected the pyramidal neurons in the CA1 hippocampus against DND normally induced by ischemic insult, which indicating that CIP induced ischemic tolerance on the pyramidal neurons in the CA1 hippocampus. However, the injection of AS-ODNs into the lateral cerebroventricle blocked the neuro-protection of CIP against DND induced by brain ischemic insult. These results further proved the role of GLT-1 in the brain ischemic tolerance induced by CIP in rats.
Animals ; Brain ; pathology ; Brain Ischemia ; drug therapy ; CA1 Region, Hippocampal ; pathology ; Excitatory Amino Acid Transporter 2 ; metabolism ; Ischemic Preconditioning ; Oligodeoxyribonucleotides ; pharmacology ; Oligonucleotides, Antisense ; pharmacology ; Pyramidal Cells ; metabolism ; Rats ; Rats, Wistar

Base Sequence ; Hepacivirus ; drug effects ; genetics ; Hepatitis C ; drug therapy ; virology ; Humans ; Molecular Sequence Data ; Oligonucleotides ; therapeutic use ; Phosphorothioate Oligonucleotides ; therapeutic use

OBJECTIVETo study the effect of phosphorothioate antisense Bcl-xL oligodeoxynucleotides on apoptosis and thermosensitivity of BcaCD885 cells.

METHODSAfter phosphorothioate antisense Bcl-xL oligodeoxynucleotides were transfected into BcaCD885 cells. The characteristics of apoptotic cells were evaluated by morphological observation and TUNEL staining. Apoptotic rate and Bcl-xL protein expression were analyzed with flow cytometry. The influence of phosphorothioate antisense Bcl-xL oligodeoxynucleotides on apoptotic rate of BcaCD885 cells induced by hyperthermia with 43 degrees C 40 min was also examined through flow cytometry.

RESULTSThe BcaCD885 cells transfected with phosphorothioate antisense Bcl-xL oligodeoxynucleotides displayed apoptotic morphological features. The Bcl-xL protein expression level of these cells was down-regulated significantly compared with the controlled group (P < 0.05). The apoptotic rate of these cells induced by hyperthermia was increased significantly compared with the controlled group (P < 0.05).

CONCLUSIONPhosphorothioate antisense Bcl-xL oligodeoxynucleotides can induce apoptosis and improve thermosensitivity of BcaCD885 cells.

Apoptosis ; drug effects ; Flow Cytometry ; Gene Expression Regulation, Neoplastic ; drug effects ; genetics ; Hot Temperature ; Humans ; Hyperthermia, Induced ; Mouth Neoplasms ; genetics ; pathology ; Oligodeoxyribonucleotides, Antisense ; pharmacology ; Oligonucleotides, Antisense ; genetics ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Thionucleotides ; pharmacology ; Transfection ; Tumor Cells, Cultured ; bcl-X Protein

CpG-Oligodeoxynucleotide (ODN) has two backbones. Phosphorothioate backbone (PS) shows a strong immunostimulating effect while phosphodiester (PE) shows little in vivo. 3' hexameric deoxyriboguanosine-run (3' dG6-run) conjugation to PE CpG-ODN has been reported to enhance immunostimulation and to protect against asthma when injected at the time of sensitization in mice. We evaluated the treatment effects of PE and PS CpG-ODN with or without 3' dG6-run on asthma in presensitized mice. BALB/c mice sensitized with ovalbumin and alum were challenged with 1% ovalbumin on three days. CpG-ODNs (100 microgram) or PBS were injected 4 times; 27 hr before challenge and 3 hr before each challenge (CpG-dG6: CpG-ODN with 3' dG6-run, PE*-CpG-dG6: PE-CpG-dG6 with two PS backbones at the 5' terminus). PE-CpG showed no treatment effect. PE-CpG-dG6 only increased ovalbumin-specific IgG2a. PE*-CpG-dG6 increased ovalbumin-specific IgG2a but also reduced BAL fluid eosinophils and airway hyperresponsiveness. PS-CpG increased ovalbumin-specific IgG2a, reduced airway inflammation and airway hyperresponsiveness. PS-CpG-dG6 was less effective than PS-CpG on airway inflammation and airway hyperresponsiveness. In pre-sensitized mice, PE-CpG required not only 3' dG6-run but also the modification of two PS linkages at 5' terminus to inhibit features of asthma. PS-CpG was strong enough to inhibit asthma but PS-CpG-dG6 was less effective.
Animals ; Anti-Asthmatic Agents/*therapeutic use ; Asthma/*drug therapy/physiopathology ; Bronchial Hyperreactivity/drug therapy ; Bronchoalveolar Lavage Fluid/immunology ; Deoxyguanosine/*analogs & derivatives/*chemistry ; Female ; Immunoglobulin G/metabolism ; Interleukin-12/analysis ; Interleukin-4/analysis ; Interleukin-5/analysis ; Lung/pathology ; Mice ; Mice, Inbred BALB C ; Oligodeoxyribonucleotides/*therapeutic use ; Phosphorothioate Oligonucleotides/therapeutic use ; Splenomegaly/pathology

Despite advances in neurosurgery, radiation, and chemotherapy, the prognosis of patients with malignant brain tumors still remains grim. Considerable efforts have been made to develop new therapeutic strategies for malignant brain tumors. One of the promising new therapies for brain tumors is an intervention at molecular level, and several molecular approaches have been shown to have in vitro and in vivo activities. These include the use of retroviral vectors, herpes simplex viruses, adenoviral vectors in gene transfer, and antisense vectors and oligonucleotides. Preclinical studies of retroviral vector have already been extended to clinical trials, clearly demonstrating the clinical potential of these molecular therapies. Here, I discuss the current status of molecular therapy for brain tumors together with future directions for its development.
Brain Neoplasms* ; Brain* ; Drug Therapy ; Humans ; Neurosurgery ; Oligonucleotides ; Oligonucleotides, Antisense* ; Prognosis ; Simplexvirus ; Zidovudine