# Adipolin, Chemerin, Neprilysin and Metabolic Disorders Associated with Obesity
## 4 Discussion  
### Adipokines and Anthropometric Parameters  
The first analyzed molecule, adipolin, is an adipokine with potentially beneficial effects on human metabolism [19]. According to some researchers, adipolin concentration decreases with increasing body weight. For example, [PERSON] et al. showed that blood levels of this adipokine are negatively correlated with waist circumference in patients with type 2 diabetes [4]. [PERSON] et al. found a negative correlation between adipolin levels and WHR [20] among overweight individuals. A similar relationship with the WHR among obese women was observed by [PERSON] et al. In addition, in this group, it was shown that adipolin concentration also correlated negatively with BMI [21]. The occurrence of a negative correlation with BMI in subjects without obesity was also observed by [PERSON] et al. [22]. [PERSON] et al. found, contrary to the majority of researchers, that blood adipolin concentrations in overweight and obese individuals were higher than in normal-weight participants [23]. This result is partly consistent with our observations. Indeed, in the control group, it was observed that adipolin concentrations correlated positively with body fat percentage and, among women in this group, also with body weight, BMI, waist circumference, and WHR. Among obese participants, a positive correlation between adipolin concentration and body weight and waist circumference was also found in the women's group. These studies show how difficult it is to define the relationship between adipolin levels and body weight clearly. There is some evidence that plasma neprilysin concentration correlates positively with BMI. It was shown by [PERSON] et al. among men, some of whom had metabolic syndrome. Figure 6: Insulin resistance (blue line) risk in non-obese (**A**) and obese (**B**) populations. However, not all studies support this [24]. For example, [PERSON] et al., evaluating neprilysin levels in pregnant women, did not find that it correlated with BMI [25]. In our study among obese individuals, no association between neprilysin concentrations and anthropometric indices was observed. However, somewhat surprising results were obtained in a control group, specifically among non-obese men. The neprilysin concentration in this group correlated negatively with body weight, waist circumference, BMI, and WHR. Interventional studies provided exciting findings. [PERSON] et al. observed a significant decrease in blood neprilysin concentrations among people with morbid obesity and diabetes 6 months after bariatric surgery, compared with values before surgery [26]. In contrast, [PERSON] et al. investigated how blood neprilysin concentrations were affected by a six-month weight-reduction diet leading to weight loss. The researchers showed a significant decrease in blood levels of this adipokine due to the dietary intervention in the low-fat diet group, which they did not find with the low-carbohydrate diet, despite comparable weight loss in both groups [27]. On this basis, it can be suggested that neprilysin concentrations depend more on the diet (which can lead to weight gain or loss) than on the subjects' weight. This observation may explain the discrepancy in the results obtained in the different study centers. According to most researchers, blood levels of chemerin increase with increasing body weight. For example, [PERSON] et al. showed that circulating blood levels of chemerin were significantly higher in individuals with a BMI above 25 kg/m\({}^{2}\) compared to a group with a BMI below 25 kg/m\({}^{2}\)[28]. Similarly, [PERSON] et al. found higher levels of chemerin in the blood of obese individuals than in lean individuals [29]. [PERSON] et al., in their study, also showed that patients with morbid obesity had significantly higher blood chemerin concentrations than non-obese individuals and observed that its concentration correlated positively with waist circumference and WHR [30]. Similar conclusions were reached by [PERSON] et al.