Proteolysis‐targeting chimeras (PROTACs) are heterobifunctional molecules that hijack the ubiquitin‐proteasome system to drive catalytic, sub‐stoichiometric degradation of disease‐associated proteins, offering a mechanistic advantage over occupancy‐driven inhibitors and access to ‘undruggable’ targets. However, their clinical translation is constrained by high molecular weight, poor solubility, low oral bioavailability, inefficient membrane permeability, nonspecific biodistribution, off‐target degradation, and the concentration‐dependent ‘hook effect.’ Exosomes, nanoscale extracellular vesicles with innate biocompatibility, low immunogenicity, prolonged circulation, and the ability to cross barriers such as the blood–brain barrier, offer a biologically integrated platform to overcome these limitations. This review traces the evolution of PROTAC technology, delineates the challenges of conventional delivery, and evaluates the rationale for exosomal encapsulation, including cargo protection, intracellular trafficking, endosomal escape, and release kinetics. We examine natural and engineered exosomes spanning source selection, active loading strategies, and surface functionalization for tissue‐specific homing and synthesize therapeutic applications across viral infections, cancer, neurodegenerative disorders, and inflammatory diseases. Proof‐of‐concept studies, such as camel milk‐derived exosomes delivering the BRD4‐targeting PROTAC ARV‐825, demonstrate enhanced permeability, lower IC ₅₀ values, and improved oral bioavailability. Finally, we discuss key hurdles to clinical translation: scalable production, purification, and standardization, and outline future directions for exosome‐mediated targeted protein degradation.

Neuroimmune interactions in the intestine are essential for maintaining tissue homeostasis, yet they remain poorly understood in teleost fish. This study investigated the structural and cellular organization of enteric neurons and immune cells in the intestine of goldfish (Carassius auratus) using semithin histology, transmission electron microscopy (TEM), and confocal immunofluorescence. Histological observations revealed a well-organized epithelium composed of enterocytes and goblet cells, with numerous lymphocytes located in the basal epithelium. Prominent gut-associated lymphoid tissue (GALT) was identified in both scattered and aggregated forms within the lamina propria and submucosa. Macrophages were widely distributed throughout all intestinal layers and were consistently found in close proximity to enteric neurons and nerve fibers. Ultrastructural analysis confirmed direct contacts between macrophages and neuronal elements. These macrophages exhibited typical phagocytic features, including lysosomes, vacuoles, and engulfed material, particularly in association with myenteric nerve fibers. Immunofluorescence analysis revealed strong expression of toll-like receptor 2 (TLR2) and major histocompatibility complex class II (MHC II) in macrophages and enterocytes, suggesting an active role in antigen recognition. Langerin-positive dendritic-like cells were identified in the submucosa, while CD4-positive lymphocytes showed partial colocalization with serotonin (5-HT). S100-positive cells also exhibited partial overlap with 5-HT, and goblet cells demonstrated serotonin immunoreactivity. In addition, inducible nitric oxide synthase (iNOS) colocalized with TLR2 in submucosal immune cells. These findings demonstrate a close structural and functional association between enteric neurons and immune cells, highlighting an integrated neuroimmune network in the goldfish intestine.

Diabetes mellitus (DM) is a global health challenge marked by chronic hyperglycemia, which can result in complications such as diabetic cardiomyopathy. Sitagliptin, an oral anti-hyperglycemic drug, has demonstrated efficacy in alleviating cardiovascular complications associated with DM. This study explored the impact of Sitagliptin’s potential as a therapeutic agent, functioning not only to control blood sugar levels but also to enhance vascular health and strengthen cardiac resilience in diabetes. The investigation focused on alterations in the vascular endothelial growth factor (VEGF) and its receptor-1 (FLT-1) signaling pathways, as well as its potential to suppress inflammation and oxidative stress. A number of rats received a single dose of streptozotocin (STZ) 55 mg/kg (i.p.) to induce DM. Sitagliptin was administered orally (100 mg/kg/90 days) to normal and diabetic rats, after which samples were collected for investigation. Sitagliptin significantly mitigated weight loss in diabetic rats. Its administration significantly reduced blood glucose levels and improved serum troponin I and CK-MB levels. Heart sections from diabetic rats showed a marked increase in mTOR, VEGF, and FLT-1 immune reaction, while sitagliptin-treated diabetic rats’ heart sections showed moderate immune reactions. Sitagliptin’s protective effect was also associated with reduced inflammation, and apoptotic markers. In conclusion, Sitagliptin is suggested to offer beneficial effects on the vascular health of cardiac blood vessels, thereby potentially reducing myocardial stress in diabetic patients.

The brachial plexus is the most variable part of the peripheral nervous system. The Musculocutaneous nerve is a terminal branch of the...