In recent years, several studies have been conducted on Muse cells mainly due to their pluripotency, high tolerance to stress, self-renewal capacity, ability to repair DNA damage and not being tumoral. Additionally, since these stem cells can be isolated from different tissues in the adult organism, obtaining them is not considered an ethical problem, providing an advantage over embryonic stem cells. Regarding their therapeutic potential, few studies have reported clinical applications in the treatment of different diseases, such as aortic aneurysm and chondral injuries in the mouse or acute myocardial infarction in the swine, rabbit, sheep and in humans. This review aims to describe the characterization of Muse cells, show their biological characteristics, explain the differences between Muse cells and mesenchymal stem cells, and present their contribution to the treatment of some diseases.

Acute-phase proteins (APPs) are biomarkers of systemic inflammation, which allow monitoring the response to surgery and post-operative complications. Ovariectomy (OVE) can be a useful model to evaluate surgical trauma and inflammation in feline species. The objective of this study was to evaluate and compare the acute-phase response (APR) after applying two different OVE techniques by measuring serum levels of serum amyloid A (SAA), haptoglobin (Hp), total serum proteins (TSPs), albumin (ALB), and paraoxonase-1 (PON-1) during the first 48 h post-surgery (hospital stay). Forty-two female cats were selected for elective spaying. The animals were randomly distributed into two groups: laparoscopic OVE (L-OVE) and midline OVE (M-OVE). Serum SAA, Hp, TSPs, ALB, and PON-1 were measured before surgery and 1, 6, 12, 24, and 48 h post-surgery. Unlike negative APPs such as PON-1 and ALB, SAA is the most sensitive positive APP for monitoring the inflammatory response in cats undergoing OVE following laparoscopic and conventional surgery. OVE performed in cats via both laparoscopic and midline techniques results in a significative increase in SAA levels, with early recovery, minor variations in serum total protein, and no significant changes in albumin, haptoglobin, or PON-1 over a 48-h period post-procedure. Based on SAA concentrations, the response to surgical trauma does not differ between surgical techniques.

Osteoarthritis (OA) is the most prevalent degenerative joint disease in both humans and companion animals, causing progressive cartilage destruction for which no curative treatment currently exists. Plasma rich in growth factors (PRGF) has shown chondroprotective effects in veterinary and preclinical models, but its efficacy is limited by the viscosity of synovial fluid and rapid degradation of growth factors within the joint. This study aimed to evaluate the effect of intra-articular co-administration of PRGF and urease-powered enzymatic nanobots on serum biomarkers of inflammation, oxidative stress, and cartilage metabolism in a rabbit (Oryctolagus cuniculus) full-depth chondral defect model (approval code: CEEA 2023-VSC-PEA-0242). Forty-one New Zealand White rabbits were allocated to a Control group (PRGF alone; n = 9 evaluable) or a Nanobots group (PRGF + nanobots; n = 24 evaluable). Twelve serum biomarkers were measured at baseline and days 28, 56, and 84. The Nanobots group showed markedly elevated serum hyaluronic acid at all timepoints (p < 0.006), significantly lower type II collagen cleavage neoepitope at day 28 (p = 0.018), persistently lower ferric reducing ability of plasma (p < 0.003), and higher C-reactive protein at days 56 and 84 (p < 0.035). These results provide preliminary in vivo evidence that urease-powered nanobots produce a distinct biomarker profile when combined with PRGF in a rabbit chondral defect model, with potential translational relevance for veterinary orthopedic therapy.