ABSTRACT
BACKGROUND: Therapeutic angiogenesis is a clinical intervention for controlled stimulation and augmentation of neovascularisation in ischemic tissues. Conventional therapeutic techniques involve proangiogenic factor based induction of host tissue angiogenesis. In this review, we provide a holistic idea about therapeutic angiogenesis while specifically highlighting the role of proangiogenic factors as growth factors, peptides, small molecules and polysaccharides in tissue neovascularisation. METHODS: A detailed search of peer-reviewed literature was carried out with prime focus on therapeutic angiogenesis and proangiogenic factors. The content of each literature reviewed in this paper was qualitatively analysed for particulars and relevance to the subject of study. This work has been distributed under four broad titles, namely, proangiogenic growth factors, peptides, small molecules and polysaccharides. Also, recent developments pertaining to proangiogenic factors for therapeutic angiogenesis have been detailed. RESULTS: A total of 244 literatures have been reviewed from the bibliographic database to present a conceptual understanding about the importance of proangiogenic factors in revascularisation of ischemic tissues. CONCLUSION: This review focuses on importance of various proangiogenic factors, with reference to therapeutic angiogenesis. Thorough analysis of clinical data reveals the dearth of a defined system for proangiogenic growth factor delivery. Designing of a biomaterial based paradigm for growth factor therapy, might help in enhancing clinical translation of therapeutic angiogenesis.
Subject(s)
Intercellular Signaling Peptides and Proteins/pharmacology , Neovascularization, Physiologic/drug effects , Polysaccharides/pharmacology , Small Molecule Libraries/pharmacology , Animals , Coronary Artery Disease/drug therapy , Coronary Artery Disease/pathology , Fibroblast Growth Factors/pharmacology , Fibroblast Growth Factors/therapeutic use , Humans , Intercellular Signaling Peptides and Proteins/therapeutic use , Peptides/pharmacology , Peptides/therapeutic use , Polysaccharides/therapeutic use , Small Molecule Libraries/chemistry , Small Molecule Libraries/therapeutic use , Vascular Endothelial Growth Factors/pharmacology , Vascular Endothelial Growth Factors/therapeutic useABSTRACT
Injectable hydrogels are gaining popularity as tissue engineering constructs because of their ease of handling and minimal invasive delivery. Making hydrogels from natural polymers helps to overcome biocompatibility issues. Here, we have developed an Amorphous Chitin (ACh)-Agarose (Agr) composite hydrogel using a simpletechnique. Rheological studies, such as viscoelastic behavior (elastic modulus, viscous modulus, yield stress, and consistency), inversion test, and injectability test, were carried out for different ACh-Agr concentrations. The composite gel, having a concentration of 1.5% ACh and 0.25% Agr, showed good elastic modulus (17.3 kPa), yield stress (3.8 kPa), no flow under gravity, injectability, and temperature stability within the physiological range. Based on these studies, the optimum concentration for injectability was found to be 1.5% ACh and 0.25% Agr. This optimized concentration was used for further studies and characterized using FT-IR and SEM. FT-IR studies confirmed the presence of ACh and Agr in the composite gel. SEM results showed that the lyophilized composite gel had good porosity and mesh like networks. The cytocompatibility of the composite gel was studied using human mesenchymal stem cells (hMSCs). The composite gels showed good cell viability.These results indicated that this injectable composite gel can be used for biomedical applications.
