The unveiling of adiponectin, a new adipocytokine released from WAT, was the result of a collaborative effort between two research groups in the span of two years. The Lodish Group in 1995 first identified a 30 kilo-Dalton (kDa) secretory protein expressed exclusively in adipocytes, which was termed Acrp30 at the time of the study.19 The protein was cloned a year following its discovery by the Spiegelman Group, found to reside on chromosome 3, and termed AdipoQ.20 Adiponectin has since been scrutinized immensely in its ability to modulate insulin sensitivity and other hormonal and metabolic processes.
There has been a general consensus among researchers that levels of ...view middle of the document...
Certain cancers have also been implicated in the study of adiponectin. Subjects with prostate cancer, in particular, were found to have low levels of adiponectin, a 2005 study showed.22 Adiponectin levels were also linked to the stage and histologic grade of the cancer, suggesting a causal relationship between adiponectin and prostate cancer.22 A direct role and mechanism of adiponectin on cancer and other chronic diseases will be fundamental to understanding key disease processes and combating these obesity-induced malignancies. However, a deeper comprehension of the biological activities and mechanisms of adiponectin must be elucidated beforehand.
The year 2005 marked the introduction of a new adipocytokine termed omentin-1. Omentin-1 was discovered by the Buchler Research Group as a 34 kDa protein expressed and secreted from, primarily, omental, or abdominal, adipose tissue.23 Omentin-1, also referred to as intelectin-1, presents itself as another lucrative candidate, boasting similar properties as adiponectin.24 The many opportune characteristics of omentin-1 include its ability to mediate insulin activity, promote cardiovascular and bone health, and ameliorate the inflammatory response that stem from obesity. Concentrations of omentin-1 in the body, measured in the blood, are understood to be inversely proportional to the level of adiposity, and in this sense, behave similarly to adiponectin.24 Like adiponectin, correlation studies have identified it as being inversely proportional to both the level of obesity and insulin resistance.24 Omentin-1 has been exemplified to inhibit inflammation caused by TNF-α cytokine, another powerful cytokine released by WAT, and shown to induce vasodilation in blood vessels.24 A recent 2013 study by the Liao group out of Central South University in Hunan, China provided a role of omentin-1 in stimulating human osteoblast, or bone-synthesizing cells, production, making it a potential target in osteoporotic treatment.24 However, menial literature on this potentially beneficial peptide persists. Continuing to expose and understand its biological functions will allocate more tools for researchers to bring promise to obesity research.
Summary: Pharmacological Initiatives and Future Directions
Many potential pharmacological targets have already been previously discussed in this article. This section will allude to previous statements made. The aforementioned characteristic common to nearly all obese subjects is leptin resistance. However, leptin resistance has erected a hurdle in the wake of researchers seeking remedies to appease it. Prospective studies will need to address this gap and exploit the functions of other adipocytokines and target tissues in order to reach any sort of conclusion on this matter. Antagonizing ghrelin receptors to attenuate hunger and increase energy expenditure is one such area of weakness to be bolstered. Modulating expression of inflammatory cytokines provides...