Correlations of Cerebrospinal Fluid/Plasma Fibroblast Growth Factor 21 Ratio with Metabolic Parameters in Chinese Individuals of Normal Weight.

BACKGROUND: Fibroblast growth factor 21 (FGF21) is an important metabolic regulator that has multiple beneficial effects on glucose homeostasis and lipid metabolism. Although circulating levels of FGF21 are mainly derived from liver, FGF21 is also found in other tissues and fluids including the cerebrospinal fluid (CSF). The aim of the present study was to investigate the relationships of CSF and/or plasma FGF21 levels with metabolic parameters in a normal-weight Chinese population. METHODS: Forty-five subjects (22 males and 23 females) were recruited from a patient population undergoing surgery for lower extremity injuries due to ligament damage or bone fractures below the knee in the Beijing Jishuitan Hospital. The levels of FGF21 in CSF and plasma were determined by radioimmunoassay and enzyme-linked immunosorbent assay, respectively. RESULTS: No significant differences were detected in the levels of FGF21 in CSF and plasma between males (CSF: 158.01 ± 12.10 pg/mL; plasma: 206.19 ± 7.22 pg/mL) and females (CSF: 159.27 ± 17.85 pg/mL; plasma: 203.10 ± 7.53 pg/mL). The level of FGF21 in CSF was about 75% of that in plasma. The FGF21 level in CSF was positively correlated with triglyceride level, whereas plasma FGF21 level was negatively correlated with alanine aminotransferase in women but not in men. The CSF/plasma FGF21 ratio was positively correlated with CSF FGF21 in both genders and with peripheral glucose, triglyceride, and gamma-glutamyl transferase levels in female Chinese patients. CONCLUSIONS: These results have important implications regarding the potential central actions of FGF21.

Prediction of liver injury using the BP-ANN model with metabolic parameters in overweight and obese Chinese subjects.

Nonalcoholic fatty liver disease (NAFLD) is often associated with dyslipidemia. Metabolic disequilibrium, resulting from being overweight and obesity, increases risk to cardiovascular system and chronic liver disease. Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) are standard clinical markers for liver injury. In this study, we examined association of body mass index (BMI) and metabolic markers with serum ALT, AST and GGT activity in an overweight and obese Chinese population. A total of 421 overweight and obese Chinese adults (211 males and 210 females) from The First Affiliated Hospital of Wenzhou Medical University were recruited in this study in 2014. All participants underwent anthropometric measures and phlebotomy after an overnight fast. Elevated ALT, AST and GGT levels were found in 17%, 5% and 24%, respectively. There were significant correlations between ALT and BMI, plasma triglycerides (TG), cholesterol, HDL and glucose, and between AST and plasma TG and cholesterol. GGT also correlated with plasma TG, cholesterol and glucose. The levels of ALT, AST and GGT could be predicted by BMI, plasma TG, cholesterol, HDL and glucose using the back propagation artificial neural network model (BP-ANN). These data suggest that abnormal metabolic markers could be used to monitor liver function to determine whether liver damage has occurred in overweight and obese individuals. This approach has clinical utility with respect to early scanning of liver injury or NAFLD based on routinely available metabolic data in overweight and obese population.

Cerebrospinal fluid oxytocin correlated with peripheral ALT and AST in Chinese female subjects.

OBJECTIVE: Oxytocin (OT) is primarily synthesized in the paraventricular nucleus of the hypothalamus and supraoptic nucleus of the hypothalamus in the central nervous system and exhibits a wide spectrum of central and peripheral activities. OT is involved in lipid metabolism and glucose homeostasis and plays a protective role against liver damage. METHODS: In this study, we investigated whether CSF OT levels correlates with peripheral glucose, lipid profiles, and/or liver enzymes in Chinese subjects. Sixty-nine subjects (n=36 males; n=33 females) who were recruited from Beijing Jishuitan Hospital participated in the study. Their levels of CSF OT and peripheral parameters were assayed by radioimmunoassay and continuous monitoring assay, respectively. RESULTS: There was no significant difference in CSF OT levels between males (53.09±6.88 nmol/mL) and females (52.34±6.87 nmol/mL), and no correlation found between CSF OT levels and peripheral glucose and lipid profiles. Significant negative correlation was observed between CSF OT levels and peripheral ALT and AST concentration in females but not in males. CONCLUSION: Our results support the physiological role of neuropeptides acting on brain sites to regulate liver enzymes, and shed new light on the brain-liver interaction.