Objective To investigate the effect of berberine on the serum uncarboxylated osteocalcin (ucOC) in non-alcoholic fatty liver disease (NAFLD) patients with impaired glucose metabolism.

Methods A total of 114 NAFLD patients with impaired glucose tolerance or type 2 diabetes mellitus were treated with lifestyle intervention. Among whom, 57 patients received berberine treatment with 0.5 g every time and 3 times a day. The intervention continued for 16 weeks. The osteocalcin level, serum glucose level, lipid concentration, and hepatic fat content (HFC) were measured before and after the intervention, and the relating factors of osteocalcin level were analyzed.

Results Serum osteocalcin level was significantly elevated in the berberine group compared with the control group (P < 0.001). After adjusting age, gender, and body mass index (BMI), the improvement of serum osteocalcin level in the berberine group (4.603.50, 5.70) was still significantly higher than that in the control group (0.96-0.14, 2.05, P < 0.001), with mean difference of 3.64 (95%CI 1.74-5.55). Subgroup analysis showed that the effect of osteocalcin improvement of berberine was more significant in non-obese old male patients. Partial correlation analysis showed that the difference of serum osteocalcin level was negatively correlated with BMI, body weight, waist circumference, HFC, glycated hemoglobin 1c (HbA1c), and total cholesterol (TC) before and after treatment after age and gender adjustment (P < 0.05).

Conclusions The effect of berberine on improving metabolic disorders in patients with NAFLD accompanied by impaired glycometabolism is related to the increase of serum uncarboxylated osteocalcin level.