Recent Patents on Regenerative Medicine - Volume 4, Issue 3, 2014

Myocardial infarction results in loss of cardiac muscle and deficiency in cardiac performance. Likewise, peripheral artery disease can result in critical limb ischemia leading to reduced mobility, non-healing ulcers, gangrene and amputation. Both of these common conditions diminish quality of life and enhance risk of mortality. Successful advances in treatment have led to more people surviving incidences of myocardial infarction or living with peripheral artery disease. However, the current treatments are inadequate in repairing ischemic tissue. Over the last 5 years, a vast number of patents have been submitted concerning the use of stem cells, which correlates with the exponential growth in stem cell publications. Exploiting stem cell therapy offers a real potential in replacing ischemic tissue with functional cells. In this paper, we review recent patents concerning stem cell therapy that have the potential to provide or potentiate novel treatment for ischemic cardiovascular disease. In addition, we evaluate the promise of the inventions by describing some clinical trials that are currently taking place, as well as considering how current research on ischemic cardiovascular disease may change the patent landscape in the future.

Over the past 15 years, the development of magnesium (Mg)-based biodegradable materials has undergone considerable progress and has demonstrated great potential for orthopedic applications. Mg-based biomaterials possess many advantages over newly developed and current applied biomaterials as bone implants, such as favorable in vivo biological properties, mechanical properties and density similar to those of natural bone, and Young’s modulus much lower than Ti-based alloys developed for biomedical applications. However, the main concern with the Mg alloys is related to their rapid corrosion in the physiological environment that can lead to premature failure of the implant due to poor mechanical properties and also to adverse effects caused by the accumulation of metal ions in the surrounding tissues. To adjust the corrosion rate of Mg-based materials so as to match the rates of bone healing, extensive research has been undertaken on modification methods such as alloying and various surface modifications including coating techniques. This article reviews literature and recent patents focusing on strategies used to improve the performance of Mg-based biomaterials.

Cardiovascular diseases represent the first cause of death in industrialized countries. To date, cardiac surgery is still considered the preferential treatment especially for those patients with severe heart failure. For these reasons, over the years the number of patents and applications in the cardiothoracic surgical area has notably improved probably than any other research field, starting from heart valves, devices and stents and including today the modern tissue engineering such as 3D scaffolds, patches and tissues. In this paper, we review the last recent patents specifically relevant to cardiothoracic surgery, beyond a simple description of inventions; we have also attempted to offer a broad overview on the scientific background and to highlight issues that still need to be addressed in the next future.

Experimental works in the field of reconstructive plastic surgery have been especially focused in restorative procedures based on flaps and peripheral nerve regeneration. Those involving the use of VEGF gene therapy showed generated particular interest but also many significant conclusions in both fields of reconstructive surgery which are currently introducing in the operating room. Interestingly, composite tissue allotransplantation methods joined the possibility to perform anatomical and functional reconstructions, since skin, muscle or bones can be transferred together, but also the concomitant nerves, which will be responsible to produce the movements of these transplanted tissues like in facial transplantation or limb transplantation. During reconstructive surgeries involving flaps, partial or complete ischemia of tissues can be a common complication, especially after free tissue transfer. For this reason, there is always a reasonable risk of flap necrosis that can lead to the loss of the reconstructive procedure due to venous or/and arterial insufficiency. On the other hand, after nerve damage, axons distal to the nerve crush begin to degenerate. As a consequence, the functional connections between motor axons and muscles are finally damaged leading to progressive muscle atrophy. When nerve continuity is repaired, the proximal stumps of injured axons are in condition to sprout within the distal nerve stumps. Experimental studies demonstrated the utility and efficiency of growth factors in stimulating neoangiogenesis in order to improve flap survival as well as in the promotion of axonal sprouting which is an important point for nerve regeneration. Among the ones, the Vascular Endothelial Growth Factor (VEGF) has shown to be an efficient therapeutic agent in both fields. Gene therapy based on adeno-associated viruses, liposomes or nanoparticles is the accepted method to develop the new angiogenesis and nerve promotion as these carriers are able to efficiently deliver therapeutic genes to flaps and nerves. Nevertheless, there are still many obstacles to be solved like the therapeutic maintenance of VEGF production along the period of time necessary to perform the desired effects, but also the use of VEGF as a preventive factor to avoid flap failure in reconstructive procedures. This reviews describes the advances in regenerative medicine in flap and nerve surgery using VEGF gene therapy and related patents.