Synthesis and properties of a novel modified nucleic acid, 2'-N-methanesulfonyl-2'-amino-locked nucleic acid.

2'-Amino-locked nucleic acid has a functionalizable nitrogen atom at the 2'-position of its furanose ring that can provide desired properties to a nucleic acid as a scaffold. In this study, we synthesized a novel nucleic acid, 2'-N-methanesulfonyl-2'-amino-locked nucleic acid (ALNA[Ms]) and conducted comparative studies on the physical and pharmacological properties of the ALNA[Ms] and on conventional nucleic acids, such as 2'-methylamino-LNA (ALNA[Me]), which is a classical 2'-amino-LNA derivative, and also on 2',4'-BNA/LNA (LNA). ALNA[Ms] oligomers exhibited binding affinities for the complementary RNA strand that are similar to those of conventional nucleic acids. Four types of ALNA[Ms] nucleosides exhibited no genotoxicity in bacterial reverse mutation assays. The knockdown abilities of Malat1 RNA using the Matat1 antisense oligonucleotide (ASO) containing ALNA[Ms] were higher than those of ALNA[Me] and were closer to those of LNA. Furthermore, the ASO containing ALNA[Ms] showed different tissue tropism from that containing LNA. ALNA[Ms] exhibited biological activities that were distinct from conventional constrained nucleic acids, suggesting the possibility that ALNA[Ms] can serve as novel modified nucleic acids in oligonucleotide therapeutics.

Altered Biodistribution and Hepatic Safety Profile of a Gapmer Antisense Oligonucleotide Bearing Guanidine-Bridged Nucleic Acids.

Guanidine-bridged nucleic acid (GuNA) is a novel 2',4'-bridged nucleic acid/locked nucleic acid (2',4'-BNA/LNA) analog containing cations that exhibit strong affinity for target RNA and superior nuclease resistance. In this study, Malat1 antisense oligonucleotide (ASO) bearing GuNA was evaluated for target knockdown (KD) activity and tolerability. The GuNA ASO did not interfere with RNase H recruitment on the target RNA/ASO heteroduplex and did show potent target KD activity in a skeletal muscle-derived cell line equivalent to that of the LNA ASO under gymnotic conditions, whereas almost no KD activity was observed in a hepatocyte-derived cell line. The GuNA ASO exhibited potent KD activity in various tissues; the KD activity in the skeletal muscle was equivalent with that of the LNA ASO, but the KD activities in the liver and kidney were clearly lower compared with the LNA ASO. In addition, despite the higher accumulation of the GuNA ASO in the liver, levels of aspartate aminotransferase and alanine aminotransferase with the GuNA ASO administration were not elevated compared with those induced by the LNA ASO. Our data indicate that the GuNA ASO is tolerable and exhibits unique altered pharmacological activities in comparison with the LNA ASO in terms of the relative effect between liver and skeletal muscle.

Relationship between matrix metalloproteinase-3 serum level and pulmonary artery systolic pressure in patients with rheumatoid arthritis.

Activity of rheumatoid arthritis (RA) has been evaluated by various biomarkers including matrix metalloproteinase (MMP)-3, but the relationship between the levels of biomarkers and elevation of pulmonary artery systolic pressure (PAs) has not been evaluated in detail. We sought to determine the utility of MMP-3 with other biomarkers for the prediction of PAs in patients with RA. Blood samples for biomarkers and echocardiography were obtained in 100 consecutive patients with RA. PAs was measured by continuous-wave Doppler echocardiography and was correlated with laboratory findings. PAs had a fair correlation with MMP-3 (r = 0.53, p < 0.001) and a weak correlation with KL (Krebs von den Lungen)-6 (r = 0.36, p < 0.001) and rheumatoid factor (r = 0.25, p = 0.011). MMP-3 had a fair correlation with pulmonary vascular resistance (r = 0.42, p < 0.001), but MMP-3 was not related to cardiac output (r = 0.09, p = 0.352). Thirty-nine patients had impaired left ventricular diastolic function. There was no significant differences in PAs and pulmonary vascular resistance (PVR) between the patients with and without impaired left ventricular diastolic function. When 5 variables (age, MMP-3, C-reactive protein, KL-6, and rheumatoid factor) were used in the multivariate analysis, MMP-3 (partial regression coefficient = 0.553, p < 0.001) emerged as the most important variable related to the elevation of PAs. Nine patients (9%) were diagnosed to have pulmonary hypertension by echocardiography. MMP-3 value of 245 ng/ml was the optimal cut-off value for the prediction of pulmonary hypertension (sensitivity: 100%, specificity: 67%, area under the curve 0.89). Thus, a close relation of MMP-3 with PAs and PVR indicate that rise in PAs in patients with RA was ascribed to increase in PVR due to underlying systemic inflammation-mediated pulmonary vascular remodeling.

Intravascular hemolysis in patients with mitral regurgitation: Evaluation by erythrocyte creatine.

BACKGROUND: Intravascular hemolysis has been reported in patients with cardiac valve prostheses, but intravascular hemolysis in patients with mitral regurgitation with native valve has not been evaluated in detail. We designed a study to elucidate the impact of regurgitation flow on intravascular hemolysis in patients with primary mitral regurgitation by measuring erythrocyte creatine. METHODS: Erythrocyte creatine was enzymatically assayed in 29 patients with moderate to severe primary mitral regurgitation and 12 age-matched healthy volunteers. The size and characteristics of mitral regurgitation were determined by color Doppler echocardiography. RESULTS: Erythrocyte creatine was significantly higher in patients with eccentric jet (n=17, 2.64±0.77µmol/g Hb) than that of central jet (n=12, 1.68±0.13µmol/g Hb) and control subjects (1.39±0.25µmol/g Hb). Patients with eccentric jet had a significantly lower erythrocyte count and hemoglobin (385±58 x104/µL and 116±19g/l) compared to those with central jet (450±47×104/µL and 137±14g/l) and control subjects (433±31×104/µL and 134±19g/l). There were no significant differences in age, estimated glomerular filtration rate, pulmonary artery systolic pressure, left atrial size and left ventricular end-diastolic dimension between patients with eccentric jet and central jet. CONCLUSIONS: Intravascular hemolysis associated with subclincal anemia in patients with eccentric jet was due to the destruction of erythrocyte by collision of the eccentric jet to the atrial wall.

3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors prevent the progression of renal dysfunction in Japanese hypertensive patients.

AIM: The aim was to determine whether the use of statins prevents the progression of chronic kidney disease (CKD) in hypertensive patients. METHODS: We retrospectively reviewed data obtained from hypertensive patients, and subjects with diabetes mellitus and those undergoing hemodialysis were excluded. At total of 227 patients were enrolled (83 men, mean age 73 years) and 90% of the patients were of CKD stage 2 or 3. The patients were divided into two groups: those treated with statins (n = 93) and those not treated with statins (n = 134). Renal function was evaluated by estimated glomerular filtration rate (eGFR). RESULTS: The statin group and the non-statin group were similar in age, sex, blood pressure, follow-up period and prescriptions of antihypertensive medicines. The eGFR in the statin group increased from 62 +/- 14 to 66 +/- 15 (mL/min per 1.73 m(2)), whereas it decreased in the non-statin group from 69 +/- 16 to 64 +/- 18 (mL/min per 1.73 m(2)). The annual eGFR improved in the statin group (2.5 +/- 6.6 mL/min per 1.73 m(2)/year), but decreased in the non-statin group (-3.3 +/- 6.6 mL/min per 1.73 m(2)/year) (P < 0.001). When the patients were divided into two groups by low-density lipoprotein (LDL) cholesterol levels at the second evaluation, annual eGFR improved in the group of LDL to below 100 mg/dL (n = 99) (0.4 +/- 7.2 mL/min per 1.73 m(2)/year), but decreased in the other group (n = 128) (-1.9 +/- 7.0 mL/min per 1.73 m(2)/year) (P = 0.018). CONCLUSION: Lipid-lowering intervention with statins inhibits the progression of CKD in hypertensive patients.

Establishment and evaluation of cancer-specific human monoclonal antibody GAH for targeting chemotherapy using immunoliposomes.

To establish human monoclonal antibodies suitable for targeting chemotherapy, we prepared a panel of human-mouse hybridomas, using mouse myelomas and lymphocytes of regional lymph nodes excised from cancer patients, and selected antibodies on the basis of their specificity of binding to the surface of viable cancer cells derived from fresh cancer tissues. A selected antibody, named GAH, was found to react with viable cancer cells from 21/22 stomach and 13/20 colon cancer tissues. As for further analysis, complementary DNAs encoding GAH were cloned and recombinant GAH (rGAH) was obtained from established CHO cells transfected with GAH expression vectors. rGAH selectively stained cancer cells in human tissue sections from 13/14 stomach, 4/11 colon, 5/11 mammary, and 0/7 lung cancers, while no positive staining was observed in those of non-tumor and various normal specimens. Notably, using confocal fluorescence microscopy, rGAH was not only bound to the surface of cancer cells, but was also internalized by the cells. The potential of rGAH for intracellular drug delivery was subsequently evaluated using rGAH-conjugated, doxorubicin (DXR)-encapsulated immunoliposomes. The immunoliposomes were also internalized into the cancer cells and finally DXR was delivered to the cell nucleus. Furthermore, the immunoliposomes could inhibit the growth of DXR-insensitive stomach cancer cells (B37) in an in vivo model. These results suggest that a GAH-utilized liposome-targeting technique will provide a potent and useful cancer chemotherapy with broad applications for cancer patients.