Traditionally accepted treatments for obesity were diet control, exercise, and behavior therapy, and drug usage is also increasing. Obesity is now considered to be a disease and at the same time an important risk factor for hypertension, diabetes mellitus, and cardiovascular diseases. It is obvious that treating obesity may help in prophylaxis of these related diseases and their complications, but this should be clearly distinguished from body contour correction, which reduces the fat tissue of a specific part of the body. Body contour correction can sometimes reduce the risk factors of obesity but more importantly, it increases patients with their body image. A typical example of body contouring is liposuction. It is an invasive procedure that is performed under general anesthesia and is relatively expensive. Moreover, fatal complications may take place, such as fat embolism and sepsis, although the incidence is very rare. For this reason, many new body contouring procedures has been recently introduced for local fat tissue reduction. Although many of these procedures are available to the public, few of them have been properly tested for their efficacy and safety for use in the reduction of adipose cells and tissues.
Lately, a drug composed of PPC, which is extracted from soybean oil, was introduced. PPC is mainly composed of lecithin and is an important phospholipid in the cell membrane. This substance influences triglyceride metabolism including cholesterol, and increases the solubility of cholesterol, which may cause changes in the composition of fat deposits and prevents plaque aggregation of adipose tissue. As a result of this pharmacologic mechanism, PPC is currently used as a medicine for many diseases such as lipid atheroma, hypercholesterolemia, fat embolism, fatty deposits, atherosclerotic plaque, metal disturbances, and liver cirrhosis caused by drugs or alcohol [11
PPC has gained some popularity in recent several years as a prevalent form of injection lipolysis material and has become popular in the United States, Europe, and South America for this purpose [12
]. Mesotherapy is also an injection form of lipolysis which is currently popular, but it differs from PPC in that the former is a "size-reducing" procedure whereas the latter destroys the adipose cells. This is why the brand names for this therapy include the Lipodissolve and fat-away.
PPC was first introduced into medicine in the 1960s. It was firstly used as a treatment option for cardiovascular accident, cerebrovascular diseases, and dementia prophylaxis. It was in the 1980s when PPC usage was initially reported for aesthetic purposes at the International Convention of Mesotherapy in Paris. In the convention, Doctor Sergio Magguiori from Italy first announced the original use of PPC for its lipolytic effect on eyelid xanthelasma. In the mid-1990's, a Brazilian dermatologist, Doctor Patricia Rittes [13
], published a PPC usage manual for removing infraorbital fat tissue. This initiated the invention of many new partial lipolysis techniques worldwide, and clinical studies are now in progress in the US under US Food and Drug Administration approval. In 2006, Doctor Franz Hasengschwandtner [14
] from Austria published his findings that 441 patients who received PPC injections all experienced a lipolysis effect. He described in his article that this PPC injection therapy is very safe, as all but 6 patients who were enrolled in his study were satisfied with their results. Likewise, PPC injection as lipolysis treatment is becoming a matter of interest worldwide [13
The efficacy of PPC is generally accepted, but there have been relatively few good studies about the safety of the treatment, although few complications have been reported. Also, some recent studies suggest that DCA has some effect in lipo-destruction in vitro
]. This remains a question to be addressed in future research.
The present experiment on the lipolytic effect of PPC/DCA in a rat model has provided a useful clinical basis for the efficacy of PPC/DCA and a foundation for a future clinical trial. The rat inguinal fat pad model we proposed for the study of lipolysis may also become a useful tool as it is anatomically orderly and simple to manipulate.
In conclusion, the PPC/DCA-injected group and the control group had significantly different quantities of normal fat tissue, inflammation, necrosis, and fibrosis in a rat inguinal fat pad model. This suggests the injection of PPC/DCA affects the fat tissue component histologically and this can be the clinical basis for additional safety research and for a future clinical trial.