Fasting concentrations of nesfatin‐1 are negatively correlated with body mass index in non‐obese males

Background We recently identified a novel anorexigenic protein, nesfatin‐1, which is processed from nesfatin/nucleobindin‐2 (NUCB2). However, the clinical importance of this protein has not been determined. Objective To investigate its clinical significance in humans, we have established a new specific enzyme‐linked immunosorbent assay (ELISA) for human nesfatin‐1 in peripheral blood and measured its circulating concentration in healthy subjects. Design The new sandwich‐type ELISA method was validated and then used to measure nesfatin‐1 levels in plasma samples, under overnight fasting conditions, followed by oral glucose tolerance and meal tests. Patients and measurements A total of 43 nonobese males (age: 24·5 ± 0·6 , body mass index (BMI); 21·1 ± 0·3 kg/m²) were recruited to the study for evaluating fasting concentrations of nesfatin‐1. In those, fifteen subjects underwent a 75‐ g oral glucose tolerance test (OGTT) and another 15 underwent a meal test. In addition, fasting concentrations of nesfatin‐1 were measured in nine males with high BMI (age: 32·4 ± 3·7 , BMI; 37·3 ± 3·8 kg/m²). Results Peripheral concentrations of nesfatin‐1 showed a significant negative correlation with BMI, percentage body fat, body fat weight and blood glucose (P < 0·05). Nesfatin‐1 concentrations were not significantly changed during OGTT and meal tests. Fasting nesfatin‐1 levels were significantly lower in subjects with high BMI compared to nonobese subjects (P < 0·05). Conclusions A new specific and sensitive ELISA for nesfatin‐1 was established. Further accumulation of clinical observations is necessary to clarify the role of circulating nesfatin‐1 in various metabolic disorders.