RNA sequencing provides novel insights into the pathogenesis of naturally occurring myxomatous mitral valve disease stage B1 in beagle dogs.

Myxomatous mitral valve disease (MMVD) is the most common cardiovascular disorder in dogs with a high prevalence, accounting for approximately 75% of all canine heart disease cases. MMVD is a complex disease and shows variable progression from mild valve leakage to severe regurgitation, potentially leading to heart failure. However, the molecular mechanisms and age-related changes that govern disease progression, especially at the early stage (B1) before the development of discernable clinical signs, remain poorly understood. In this prospective study, we aimed to compare gene expression differences between blood samples of aged beagle dogs with stage B1 MMVD and those of healthy controls using RNA sequencing. Clinical evaluation was also conducted, which revealed minimal differences in radiographic and echocardiographic measurements despite distinct biomarker variations between the two groups. Comparative transcriptomics revealed differentially expressed genes associated with extracellular matrix remodeling, prostaglandin metabolism, immune modulation, and interferon-related pathways, which bear functional relevance for MMVD. In particular, the top 10 over- and under-expressed genes represent promising candidates for influencing pathogenic changes in MMVD stage B1. Our research findings, which include identified variations in clinical markers and gene expression, enhance our understanding of MMVD. Furthermore, they underscore the need for further research into early diagnosis and treatment strategies, as, to the best of our knowledge, no prior studies have explored the precise molecular mechanisms of stage B1 in MMVD through total RNA sequencing.

Suppression of the TRIF-dependent signaling pathway of Toll-like receptor by CDr10b in RAW264.7 macrophages.

Toll-like receptors (TLRs) recognize distinct pathogen-associated molecular patterns and play a critical role in innate immune responses. TLR signaling pathways can be largely classified as either myeloid differential factor 88 (MyD88)- or toll-interleukin-1 receptor domain-containing adapter inducing interferon-ß (TRIF)-dependent pathways. Compound of Designation red 10 binding (CDr10b) was synthesized to investigate its role in neuroinflammatory diseases. This study was conducted to determine whether CDr10b can affect TLR signaling pathways. CDr10b suppressed NF-κB activation as well as COX-2 and iNOS expression induced by TLR3 or TLR4 agonists. CDr10b also suppressed the activation of interferon regulatory factor 3 (IRF3) and the expression of interferon inducible protein-10 (IP-10) induced by TLR3 or TLR4 agonists. These results indicate that CDr10b can modulate the TRIF-dependent pathway of TLRs and has the potential to become a new therapeutic drug for chronic inflammatory diseases.