StuartParks

StuartParks __The Classification and Uses of Platelet Rich Plasma__ __Introduction__

It is very obvious that throughout the course of human history, it has been science that has pioneered humanity through any and all obstacles thrown in its way. From plagues to famine, to war and other such competitions, the light that science brings has always shown us where to go. It is because of that light that we explore new avenues that in the past where either too dark, or too misunderstood to go down. As we reach a heightened level of civility in our collective humanity, a sense of preservation is endowed in all of us. We all try to take care of our health, make decisions that prolong our lives, and do the best we can to survive. However, despite our best intentions, accidents happen. Random acts of chance occur. And we are often left to the machinations of the world. Much of the population has had a trip to the ER. It is just a fact of life that we will eventually need medical attention, whether it be severe or non-severe. In this respect, it has become a forefront of our scientific agenda to advance medicine. Chemically and biologically, this is what most of the “industry” of science funnels into. It is through this that we have stumbled upon the very promising concept of platelet rich plasma. This is of huge importance to us, as this discovery allows us to not only live better, but also live with a renewed sense of vigor, as we look forward to the next innovation that we as a species come to pass as not only one of the greatest, but also the best. Now before the platelet rich plasma, or PRP, can be classified, it first must be explained. Humans have a very natural healing system, and this is propagated by the blood in our bodies. When ever we are wounded, we tend to bleed from those wounds. When this occurs, there is actually a large chemical reaction going on, that happens right on our skin. The blood reacts with the oxygen in the air to coagulate and close the wound. This is nothing new, and shouldn’t be surprising information. Though what is interesting, is how platelets affect this process. By “plugging” the site of the wound, platelets act as the first line of defense during an open wound. So, the higher the concentration of platelets, the faster the wound is healed [1]. This concept is what first introduced the idea of created plasma with a high concentration of platelets.

__Classifications of PRP__

Now that the idea of the importance of platelets is understood, we can begin to look at the various types of PRP. They are pure PRP, leukocyte rich PRP, pure plasma rich fibrin, and leukocyte rich fibrin. These classifications are all very unique and distinguishable from one another. The chemical compositions of these are very dissimilar however, and finding ways to produce all of them was not an easy challenge. However, the procedures for this were all determined, and it is based on these procedures that the plasma is classified. In order to gather any PRP, a sample of blood is drawn from the victim and after anti-coagulants are added, they are centrifuged down to separate the blood into three distinct layers. The bottom layer is all red blood cells, and they are largely ignored. The next layer is a sort of “buffy” layer, which houses a large concentration of the platelets. The upper layer is largely plasma with a low concentration of platelets. It is here that the classifications split, and so first we will focus on pure PRP. To harness this, after the first step of centrifuging is complete, all layers excluding the red blood cells are extracted and again centrifuged, this time at a much higher force. What is left over is the lower layer consisting of very concentrated platelets, and the upper layer of platelet poor plasma. With this however, much of the leukocytes are left out, and few if any are in the final product. Leukocyte rich PRP, however, tries to eliminate this factor. After initial centrifuging, the entire layer of concentrated platelets, along with some red blood cells, are extracted, and then centrifuged once again at high speed. This gives the sample an upper layer of vey platelet poor plasma, and this layer is discarded. After this, some chemicals, including calcium chloride, are introduced to the leukocyte rich PRP. The last two classifications are very unique [2]. They utilize the same first steps of centrifugation as the first two do, but what follows sets them apart. The upper two layers are collected, and placed in a tube containing a coagulating agent, generally calcium chloride. This leads to clotting, and after high speed centrifugation, they are left with a clot of highly concentrated platelets, which has a very rigid fibrin complex, which overall adds to the stability of the plasma. While the classifications are necessary to garner an understanding of what PRP is, it is the uses of PRP that are of the most importance.

__Surgical Applications of Platelet Rich Plasma__

Surgery, overall, is a very effective way to help someone in need recover from an otherwise life changing injury. However, the pain associated with recovering from the surgery is often times a very hard stage for people. However many studies have shown that surgeries utilizing the chemical opportunities that PRP brings helps to reduce the recovery stage. It is stated that in a test group where some patients were treated with PRP, while others weren’t, the recovery of those that were treated with PRP had a much easier time during recovery, and out shone the others during tests of physical stress [6]. This may have had to do with the growth factors that are associated with platelet rich plasma. It is no secret that platelets in general house growth factors within them, and that these growth factors act in many cases as stem cell boosters, increasing the stock amount of stem cells available in adults. With platelet rich plasma, a higher concentration of these stimulating growth factors are being applied to the area most in need of new cells. By this logic, it is only sensible that more of the healing ability of stem cells are being directed at this area. More substance to this is given by the trials of those in a group with osteoarthritis [3]. Osteoarthritis, or OA, is a severely debilitating disease that is associated with great pain. In a group of over 600 subjects, roughly 50% were treated with PRP. This group showed considerable decreased pain levels, while some cases actually showed a complete reversal of the disease. This is simply more proof of the chemically active growth hormones stimulating stem cells in adult humans [7]. While the overall majority did not get a reversal of the disease, there was no case in which a patient became worse while being treated with PRP. In another study, this time with animals, defects were created in the subjects, making them lose tissue, fibrin, and many other structures were weakened. In this experiment, the subjects were treated with PRP, while a control group was healing naturally. The PRP group was then examined, and on the whole, they had healed exponentially better than the control group [8]. The tissue that had been removed had all healed, while the fibrin damaged had grown back thicker and more vibrant than before, and at a much faster pace than the control group. In another similar experiment, rat’s femurs were broken then healed with PRP. Once again, there was a control group that was not healed with PRP. After a few weeks of healing, the femurs were then tested to see what amount of stress they could withstand. The rats healed with PRP showed an incredible resistance of over 100N, while the group that had not received PRP had a much lower resistance. This had great implications in the use of PRP in biomedical repair of bones. Much of this is due to the awesome power that PRP has in instigating bone regeneration [4]. Chemical compounds capable of osteogenesis have always been at the heart of every biochemists experiments. And in this experiment, it was shown to be one of incredible power. PRP has been shown to exhibit the effects of TGF-B1 (transforming growth factor) and platelet derived growth factor (PDGF)[9]. These, among a few other growth factors, attribute to the fact that platelet rich plasma can in effect regrow bone cells, or bone tissue. These obviously have great implications for surgical use, and not only that, but for therapeutic use as well. Another use of this platelet rich plasma is to improve musculoskeletal cell strength. The implications of previous use of platelet rich plasma shows us that it has the potential to have a huge impact on the world of tendon and ligament repair. As is common knowledge, ligaments, once damaged have a very hard time repairing themselves. It is only through very tedious and careful caution that one is able to fully recover from an injury of that magnitude [10]. The surgical implications of this platelet rich plasma are immense. There are also studies that show us how the cavities of our sinuses could be improved with the application of platelet rich plasma to affected areas. In the grand scheme of things, perhaps platelet rich plasma is not the ultimate answer.

__Platelet Rich Plasma in Sports__

Recently it has come to the attention of some sports officials that surgical procedures utilizing platelet rich plasma could be a covert form of “doping” [5]. Doping is a term used to describe a player who tries to gain an unfair advantage in the sport they are playing by utilizing performance enhancing drugs. Such famous players guilty of this, like Marks Maguire and Lance Armstrong, were guilty of taking direct performance enhancing drugs, which may have attributed to their overall success in their respective sports of baseball and cycling. The performance enhancing drugs they were taking however were anabolic steroids, which directly affected their natural hormonal balance of testosterone. Remember, platelet rich plasma was shown to have growth factors associated with it [11]. In this way, a player technically could schedule a minor surgery simply to be dosed with some platelet rich plasma, and in doing so give him a potentially performance enhancing boost over his colleagues. It was a real issue, and was even brought up before the World Anti-Doping Agency. It was seriously considered that this might affect a players performance due to the growth factors associated with the platelet rich plasma. However, this claim was dropped as there is no correlation between platelet rich plasma and increased testosterone or other potentially performance enhancing factors [12]. In the end, there simply was no evidence that any of the growth factors were as potent or even as serious as the other ones that were currently available at the time. It was an issue that was put down due to scientific reasoning, and it was a case in which there was no severe public dispute. This was mainly due to the diligence of the scientific community stepping in and doing their job efficiently. It is quite possible that if the scientific community did not act as diligently as they did, that this issue could have erupted into a serious debate, one that would have eventually had to be settled by the very scientists who had let the ball drop in the beginning. Luckily though, none of that happened and the scientific community gained a small victory. Despite the possible negative connotation that may have been stuck with platelet rich plasma, there is no reason that its uses shouldn’t be explored further.

__Uses for Systemic Effects of Platelet Rich Plasma__

As mentioned earlier, platelet rich plasma does introduce new growth factors into the body of whoever has received the treatment[13]. What kind of stimulants due to these growth factors, are released into the body of the receiver of this treatment? Well, a study was done to show that while certain factors such as bFGF (basic fibroblast growth factor) and vascular endothelial growth factor (VEGF)[14]. These were actually elevated in patients who took leukocyte rich platelet rich plasma, which may sound alarming. However, no elevated levels of human growth hormone (hGH) were detected. This stands to reason that the World anti-Doping Agency was correct in their interpretation of platelet rich plasma as simply a medical tool to help alleviate the suffering of many. It is notable that a possible ergogenic effect may be instigated by the use of platelet rich plasma [15]. An ergogenic effect is simply an unintentional increase in performance. However, this increase in performance is very short lived, and most who undergo this type of healing process will never have the time or, quite frankly, the opportunity to utilize the potential boost to any performance. In this way, it is highly unlikely that any sports contender could abuse platelet rich plasma in such a way that could severely affect the outcome of any sporting event. But in the aftermath of it all, perhaps that is a blessing in disguise. This is all speculation, but it could be possible that with enough long term exposure to this, platelet rich plasma could have severely beneficial effects on those who are crippled or are in some way lamed. The growth hormones have a short term effect, but repeated exposure to it would keep feeding those growth factors over a much longer period of time, in essence funneling these factors into someone who is lacking in them. In this way, a crippled or lamed individual could perhaps walk or run or have control over a limb that otherwise have been lost to an unfortunate circumstance. But again, this is all speculation, and little if any support for that claim would or could be found. For now, it is enough that it heals peoples wounds much faster, and keeps them from feeling an over abundance of pain. However there are other uses for platelet rich plasma.

__Uses in Dentistry__

There are many important bones in our bodies. Ones that we often forget about is our teeth. Teeth for a very long time have been the focus of many individuals who wish to brighten up another’s day. Well certain individuals now certainly have a brighter smile, due to the impact that platelet rich plasma has had on their lives. The experiment being talked about had dogs receive dental implants, some of which had been treated with platelet rich plasma [16]. The purpose of this experiment was to see if treating the teeth with platelet rich plasma would have any effect on the operation of implanting the teeth into the gums of the canines. It was noted that the dogs were under anesthetics during the procedure. However, after the procedure, and also after the dogs were allowed to heal up, the results were astounding. The dogs that had received teeth infused with platelet rich plasma not only had stronger teeth, but also had much healthier gum tissue in the areas surrounding those teeth. The control group of dogs, the ones treated without any platelet rich plasma enriched teeth, suffered from abscesses and other mal nutritious conditions associated with that. These findings indicated that with any kind of human trials, the results would come out to be the same[17]. It would be very beneficial for humans to use this method, as it would drastically reduce the chance of a dental procedure going wrong or becoming a worse issue for the patient. With this method, there would be much less fear of the dentist, but in the contrary, a much better appreciation for them. If this were the case, most people would more than likely want to go to their dentist, if only to have their teeth strengthened. Studies show that 8 out of 10 people have an interest in keeping their teeth healthy for the majority of their lives, and this procedure would help those people do just that.

__Conclusion__

In conclusion, platelet rich plasma is a revolutionary concept that many have seen the true potential and value of. There are countless ways in which this product could improve the quality of life for so many people. Among these are the aforementioned surgical, systemic and dental ways. It is also worth mentioning that this is also a very young product[18]. There is still much research and innovation to be put into something so promising. It is the duty of every scientist, no matter what area they come from, be it chemistry or biology to do what they can to help move the world forward. Advancing science has always been the main objective whenever anyone wants to improve humanity’s place in the world. As mentioned before, the main goal of any chemical or biological experiment is ultimately to improve the medicinal quality of whatever is out there[19]. Even if a project does not set out with that goal originally in mind, it invariably comes back to that simple fact. Improving medicine will ultimately allow us as humans to pursue the things that we want to pursue for longer. This is simply due to the fact that extended the capabilities of what we can do medically, also extends our lives, so that we can go after the things that we may not have had time for[20]. It is proven that platelet rich plasma can help us improve our bodies[21]. And let’s not forget how much our life span has extended in the past hundred years. It is medical innovations like this that keep pushing the boundaries of life expectancy in the world. Where once it was rare to see a fiftieth year, now we can say with confidence that we can reach a ninetieth year. Chemically and biologically we have been able to come to a better understanding of ourselves and of our human nature, and that is ultimately what has allowed us to push the boundaries of what we are capable of.

__Bibliography__

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