Cardiac stem cells: Current knowledge and future prospects

Regenerative medicine is the field concerned with the repair and restoration of the integrity of damaged human tissues as well as whole organs. Since the inception of the field several decades ago, regenerative medicine therapies, namely stem cells, have received significant attention in preclinical studies and clinical trials. Apart from their known potential for differentiation into the various body cells, stem cells enhance the organ's intrinsic regenerative capacity by altering its environment, whether by exogenous injection or introducing their products that modulate endogenous stem cell function and fate for the sake of regeneration. Recently, research in cardiology has highlighted the evidence for the existence of cardiac stem and progenitor cells (CSCs/CPCs). The global burden of cardiovascular diseases’ morbidity and mortality has demanded an in-depth understanding of the biology of CSCs/CPCs aiming at improving the outcome for an innovative therapeutic strategy. This review will discuss the nature of each of the CSCs/CPCs, their environment, their interplay with other cells, and their metabolism. In addition, important issues are tackled concerning the potency of CSCs/CPCs in relation to their secretome for mediating the ability to influence other cells. Moreover, the review will throw the light on the clinical trials and the preclinical studies using CSCs/CPCs and combined therapy for cardiac regeneration. Finally, the novel role of nanotechnology in cardiac regeneration will be explored.

Cardiac stem cells: Current knowledge and future prospects

Regenerative medicine is the field concerned with the repair and restoration of the integrity of damaged human tissues as well as whole organs. Since the inception of the field several decades ago, regenerative medicine therapies, namely stem cells, have received significant attention in preclinical studies and clinical trials. Apart from their known potential for differentiation into the various body cells, stem cells enhance the organ's intrinsic regenerative capacity by altering its environment, whether by exogenous injection or introducing their products that modulate endogenous stem cell function and fate for the sake of regeneration. Recently, research in cardiology has highlighted the evidence for the existence of cardiac stem and progenitor cells (CSCs/CPCs). The global burden of cardiovascular diseases' morbidity and mortality has demanded an in-depth understanding of the biology of CSCs/CPCs aiming at improving the outcome for an innovative therapeutic strategy. This review will discuss the nature of each of the CSCs/CPCs, their environment, their interplay with other cells, and their metabolism. In addition, important issues are tackled concerning the potency of CSCs/CPCs in relation to their secretome for mediating the ability to influence other cells. Moreover, the review will throw the light on the clinical trials and the preclinical studies using CSCs/CPCs and combined therapy for cardiac regeneration. Finally, the novel role of nanotechnology in cardiac regeneration will be explored.

Clinical and sonographic assessment of the side effects of intracavernous injection of vasoactive substances

The objective of this study is to evaluate the side effects of intracavernous vasoactive agents on clinical and sonographic basis. Two groups of patients were included, group I included 168 ED patients trained on self-injection therapy using one of the three protocols. Protocol A: papaverine; protocol B: PGE1; and protocol C: trimix (papaverine, phentolamine and PGE1). Patients were followed up clinically, sonographically and by laboratory investigations for 6 months to evaluate the occurrence of side effects. Group II included 21 patients presenting to our department for the first time with a complication of intracavernous injection pharmacotherapy (ICI) initiated elsewhere. In all, 168 patients of group I completed the study. Patients on papaverine had the highest incidence of complications concerning prolonged erection, subcutaneous hematoma and penile fibrosis. Postinjection penile pain was observed more with groups B and C than group A. No systemic side effects were reported. Duplex ultrasound was beneficial in detecting mild clinically impalpable fibrosis. In total, 10 patients of group II presented with prolonged erection, seven with penile fibrosis, three with cavernositis and one with intracavernous needle breakage. We conclude that although ICI therapy is an effective second-line treatment option, patients on a self-injection program should be followed up both clinically and sonographically both at the initiation phase and on regular follow-up visits.