Cardiovascular disease causes the largest number of deaths across the world. The weak regenerative ability of adult hearts originates from limited cell proliferation and polyploidization of postnatal cardiomyocytes, which severely hinders tissue repair after myocardial injury. Fetal development represents a critical window during which maternal physiological and metabolic status can shape long-term offspring cardiac structure and function. Maternal exercise represents a safe nonpharmacological prenatal intervention that confers long-term benefits to offspring health. Available evidence indicates that maternal exercise enhances placental apelin secretion and elevates α-ketoglutarate (α-KG) levels in fetal brown adipose tissue, liver, and skeletal muscle. The apelin and α-KG signaling cascade participates in epigenetic regulation and confers protective effects on offspring metabolic health. Independent animal experiments have further validated that supplementation with either apelin or α-KG alleviates myocardial infarction (MI)-induced cardiac injury in adult mice, with α-KG showing direct evidence of reactivating cardiomyocyte proliferation. Nevertheless, it remains poorly elucidated whether maternal exercise could modulate fetal cardiomyocyte proliferative capacity in offspring through apelin- or α-KG-associated signaling. This narrative review integrates current evidence and proposes a testable framework in which maternal exercise influences fetal cardiac growth and regenerative potential through placental, metabolic, and epigenetic signaling. Because direct evidence remains limited, this model should be regarded as a hypothesis that requires further experimental validation.
Peptide-Guided Nanoparticle Drug Delivery for Cardiomyocytes
Background: Nanoparticles (NPs) have been extensively utilized as a drug delivery system to control the release of therapeutic agents to treat cardiac injuries. However, despite the advantages of utilizing NP-based drug delivery for treating heart diseases, the current delivery system lacks specificity in targeting the cardiac tissue, thus limiting its application. Methods: We created three linear peptides, each consisting of 16–24 amino acids. These peptides were conjugated on the surface of NPs, resulting in the formation of cardiac targeting peptide (CTP)-NPs (designated as CTP-NP1, CTP-NP2, and CTP-NP3). To assess their effectiveness, we compared the binding efficiency of these three CTP-NPs to human and mouse cardiomyocytes. Additionally, we determined their distribution 24 h after injecting the CTP-NPs intravenously into adult C57BL/6J mice. Results: When compared to control NPs without CTP (Con-NPs), all three CTP-NPs exhibited significantly increased binding affinity to both human and mouse cardiomyocytes in vitro and enhanced retention in mouse hearts in vivo. A thorough assessment of the heart sections demonstrated that the binding specificity of CTP-NP3 to cardiomyocytes in vivo was significantly greater than that of Con-NPs. None of the three CTP-NPs were proven to cause cardiomyocyte apoptosis. Conclusions: Biocompatible and safe CTP-NP3 can target the heart via binding to cardiomyocytes. This approach of targeting specific molecules-coated NPs may help in delivering therapeutic compounds to cardiomyocytes for the treatment of heart diseases with high efficacy and low toxicity to other tissues.