Oligonucleotide therapies for nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) represents a severe disease subtype of nonalcoholic fatty liver disease (NAFLD) that is thought to be highly associated with systemic metabolic abnormalities. It is characterized by a series of substantial liver damage, including hepatocellular steatosis, inflammation, and fibrosis. The end stage of NASH, in some cases, may result in cirrhosis and hepatocellular carcinoma (HCC). Nowadays a large number of investigations are actively under way to test various therapeutic strategies, including emerging oligonucleotide drugs (e.g., antisense oligonucleotide, small interfering RNA, microRNA, mimic/inhibitor RNA, and small activating RNA) that have shown high potential in treating this fatal liver disease. This article systematically reviews the pathogenesis of NASH/NAFLD, the promising druggable targets proven by current studies in chemical compounds or biological drug development, and the feasibility and limitations of oligonucleotide-based therapeutic approaches under clinical or pre-clinical studies.

Oral administration of the herbal oligonucleotide XKC-sRNA-h3 prevents angiotensin II-induced hypertension in mice

Hypertension has become a growing public health concern worldwide. In fact, hypertension is commonly associated with increased morbidity and mortality. Currently, oligonucleotide drugs have proven to be promising therapeutic agents for various diseases. In the present study, we aimed to demonstrate that a herbal small RNA (sRNA), XKC-sRNA-h3 (B55710460, F221. I000082.B11), exhibits potent antihypertensive effects by targeting angiotensin-converting enzyme (ACE) in mice. When compared with captopril, oral administration of the sphingosine (d18:1)-XKC-sRNA-h3 bencaosome more effectively prevented angiotensin II-induced hypertensive cardiac damage and alleviated kidney injury in mice. Such findings indicated that XKC-sRNA-h3 may be a novel orally available ACE inhibitor type oligonucleotide drug for hypertension.

Orally administered BZL-sRNA-20 oligonucleotide targeting TLR4 effectively ameliorates acute lung injury in mice

The global COVID-19 pandemic emerged at the end of December 2019. Acute respiratory distress syndrome (ARDS) and acute lung injury (ALI) are common lethal outcomes of bacterial lipopolysaccharide (LPS), avian influenza virus, and SARS-CoV-2. Toll-like receptor 4 (TLR4) is a key target in the pathological pathway of ARDS and ALI. Previous studies have reported that herbal small RNAs (sRNAs) are a functional medical component. BZL-sRNA-20 (Accession number: B59471456; Family ID: F2201.Q001979.B11) is a potent inhibitor of Toll-like receptor 4 (TLR4) and pro-inflammatory cytokines. Furthermore, BZL-sRNA-20 reduces intracellular levels of cytokines induced by lipoteichoic acid (LTA) and polyinosinic-polycytidylic acid (poly (I:C)). We found that BZL-sRNA-20 rescued the viability of cells infected with avian influenza H5N1, SARS-CoV-2, and several of its variants of concern (VOCs). Acute lung injury induced by LPS and SARS-CoV-2 in mice was significantly ameliorated by the oral medical decoctosome mimic (bencaosome; sphinganine (d22:0)+BZL-sRNA-20). Our findings suggest that BZL-sRNA-20 could be a pan-anti-ARDS ALI drug.

Feasibility of using PALSAR technology as a signal amplifier for antibody bridging assay

The immunogenicity testing of oligonucleotide drugs using an antibody bridging assay has been scarcely investigated. We developed a highly sensitive antibody bridging assay model and assessed it using probe alteration link self-assembly reactions (PALSAR) technology as a signal amplifier. Methods: The concentration of each probe was optimized, and the bridging assay model was compared with and without signal amplification. Cut-point and analytical sensitivity were determined, and accuracy, precision and drug tolerance were evaluated. Results: The PALSAR bridging assay achieved a net signal 21-36 times higher than that obtained with the conventional method. The analytical sensitivity achieved was 48.8 ng/ml, with adequate accuracy, precision and drug tolerance. Conclusion: PALSAR technology is feasible for developing an antibody bridging assay using oligonucleotides as capture and detection probes.

Orthogonal analysis of dystrophin protein and mRNA as a surrogate outcome for drug development

Aim: Detection of drug-induced dystrophin in patient muscle biopsy is a surrogate outcome measure for Duchenne muscular dystrophy. We sought to establish and validate an orthogonal approach to measurement of dystrophin protein and RNA in muscle biopsies. Materials & methods: Validated methods were developed for dystrophin western blotting, mass spectrometry, immunostaining and reverse transcriptase PCR of biopsy mRNA using muscle biopsy standards. Results: Both western blotting and mass spectrometry validated methods demonstrated good linearity, and acceptable precision and accuracy with a lower limit of quantitation at 1%. Immunostaining and reverse transcriptase PCR methods were shown to be reliable. Conclusion: The described orthogonal approach is sufficient to support measures of dystrophin as a surrogate outcome in a clinical trial.