Metabolism of chylomicron-like emulsions in patients with Hodgkin’s and with non-Hodgkin’s lymphoma

Abstract

Background: Chylomicrons carry in the bloodstream dietary fats absorbed the intestine for storage in the body tissues such as adipose and muscle. The two-step chylomicron metabolism consists in lipolysis by lipoprotein lipase on vessel walls and hepatic uptake of triglyceride-depleted remnants. Chylomicron metabolism is understudied in cancer, despite its direct involvement in the patient nutritional status. We investigated this metabolism in Hodgkin and non-Hodgkin lymphoma patients, using the method of triglyceride-rich emulsions that mimic chylomicrons. Patients and methods: The chylomicron-like emulsion, labeled with [9,10- 3 H ]glycerol-trioleate and [1- 14 C ] cholesteryl-oleate was intravenously injected into 11 Hodgkin’s, 19 non-Hodgkin’s patients and 12 healthy subjects. Triglyceride kinetics evaluate lipolysis whereas cholesteryl ester kinetics evaluate remnant removal. Results: Plasma total, LDL, HDL cholesterol, apo B, apo A1 and Lp(a) values were similar between the three groups, but VLDL cholesterol and triglycerides were higher in the lymphoma groups. The fractional catabolic rate (FCR, in min −1) of the emulsion triglycerides was roughly three-fold smaller in non-Hodgkin’s (0.043±0.007, mean±S.E.M., P<0.001) and Hodgkin’s (0.045±0.009, P<0.0001) lymphoma patients compared with the control values (0.151±0.032). FCR of the emulsion cholesteryl esters, was four-fold smaller in non-Hodgkin’s (0.016±0.002, P<0.0001), and three-fold in Hodgkin’s lymphoma patients (0.024±0.006, P<0.001) compared with the control group (0.069±0.013). The lipolysis index, calculated from the decay curves of both isotopes was also markedly smaller in both groups of lymphoma patients compared with the controls. Conclusions: In both lymphoma groups, marked alterations in chylomicron lipolysis and remnant removal occurs.