Genotoxicity assessment of cardioprotective terbium hydroxide nanorods: A comprehensive in vitro and in vivo study

Therapeutic potentials of terbium hydroxide nanorods for amelioration of hypoxia-reperfusion injury in cardiomyocytes

Critical limb ischemia (CLI) refers to a severe condition resulting from gradual obstruction in the supply of blood, oxygen, and nutrients to the limbs. The most promising clinical solution to CLI is therapeutic angiogenesis. This study explored the potency of pro-angiogenic terbium hydroxide nanorods (THNR) for treatment of CLI, with a major focus on their impact on ischemia-induced maladaptive alterations in endothelial cells as well as on vascularization in ischemic limbs. This study demonstrated that, in hypoxia-exposed endothelial cells, THNR improve survival and promote proliferation, migration, restoration of nitric oxide production, and regulation of vascular permeability. Based on molecular studies, these attributes of THNR can be traced to the stimulation of PI3K/AKT/eNOS signaling pathways. Besides, Wnt/GSK-3β/β-catenin signaling pathways may also play a role in the therapeutic actions of THNR. Furthermore, in the murine model of CLI, THNR administration can integrally re-establish blood perfusion with concomitant reduction of muscle damage and inflammation. Additionally, improvement of locomotor activities and motor coordination in ischemic limbs in THNR treated mice is also evident. Overall, the study demonstrates that THNR have the potential to be developed as an efficacious and cost-effective alternative clinical therapy for CLI, using a nanomedicine approach.

The process of angiogenesis, involving generation of new blood vessels from the existing ones, is vital for the supply of oxygen and nutrients to various tissues of body system. Angiogenesis is directly associated with several physiological and pathological processes. It is well-established that impairment in angiogenesis process results in various fatal conditions. Recently, few research groups including ours demonstrated therapeutic angiogenesis through nanomedicine approach using metal oxide/hydroxide nanoparticles. However, there is still a thorough necessity for the development of novel, eco-friendly, pro-angiogenic nanomaterials. Hence, in the present study we demonstrate the in vitro and in vivo pro-angiogenic properties of terbium hydroxide nanorods (THNRs) synthesized using an advanced microwave irradiation method, along with the detailed molecular signaling cascade underlying THNRs induced angiogenesis. The in vivo wound healing and nonimmunogenicity of the THNRs have been validated in the mouse models. We thus strongly believe that the present study establishing the pro-angiogenic properties of THNRs will aid in the development of alternative treatment strategies for wound healing along with cardiovascular and ischemic diseases, where angiogenesis is the chief target.