Abstract
Background and Study Aims In patients with obesity and type-2
diabetes, short-time very low-calorie diet may ameliorate hyperglycemia and
hepatic steatosis. Whether this also implies the glucose-regulating hormone
glucagon remains to be elucidated. This study investigated the effects of a
very low-calorie diet on plasma levels of glucagon and liver fat in obese
patients with type-2 diabetes.
Patients and Methods Ten obese patients with type-2 diabetes, 6 men
and 4 women, were included. At baseline, fasting plasma glucagon, insulin
and glucose were determined, and liver fat and stiffness evaluated by
transient elastography. The subjects were then prescribed a very low-calorie
diet of maximum 800 kcal/day for 7 weeks and reexamined
after 7 weeks and 12 months.
Results At baseline, BMI was
42±4 kg/m2 and fasting glucose
10.6±3.4 mmol/l. All patients had hepatic steatosis.
Plasma glucagon was strongly related to liver fat
(r2=0.52, p=0.018). After 7 weeks of very
low-calorie diet, plasma glucagon was significantly decreased by nearly
30% (p=0.004) along with reductions of BMI
(p<0.0001), glucose (p=0.02), insulin (p=0.03),
liver fat (p=0.007) and liver stiffness (p=0.05). At 12
months follow-up, both glucagon and liver fat increased and were not
different to basal levels, despite persistent reductions of BMI
(p<0.002) and glucose (p=0.008).
Conclusion In obese type-2 diabetic subjects, plasma glucagon and
liver fat are correlated and similarly affected by a very low-calorie diet,
supporting a role of hepatic steatosis in glucagon metabolism.
