Effect of A Modified Ketogenic Diet on The Hepatobiliary System in Experimental Metabolic Syndrome: Dynamics of Apolipoprotein E and Lipoprotein Lipase

Background: Metabolic syndrome (MetS) is accompanied by dyslipidemia, impaired glucose homeostasis, systemic inflammation, and hepatobiliary dysfunction [1, 2]. Apolipoprotein E (ApoE) and lipoprotein lipase (LPL) are key components of triglyceride-rich lipoprotein metabolism [7–9]. Objective: To evaluate the effects of a modified ketogenic diet (MKD; 60% fat, 30% protein, 10% carbohydrate) on hepatobiliary, metabolic, inflammatory, and lipoprotein-related parameters in an experimental rabbit model of MetS, with particular emphasis on ApoE and LPL dynamics. Methods: Sixty Chinchilla rabbits entered the experiment. Eight formed the intact control group, whereas MetS was induced in 52 animals for 60 days using crystalline cholesterol (250 mg/kg), 5% sucrose solution, and subcutaneous insulin (0.1 U/100 g every other day) [5]. Four animals died during induction. The remaining 48 animals with MetS were allocated to six groups (n=8 each): MetS control, traditional ketogenic diet (TKD), MKD, MKD+ezetimibe (0.14 mg/kg/day), MKD+metformin (25 mg/kg/day), and MKD+metformin+ezetimibe. Treatment lasted 30 days. Biochemical variables were assessed on days 10, 20, and 30; ApoE and LPL were measured by ELISA. Results: In the MKD group, ALT decreased from 64.4±5.8 U/L on day 10 to 49.9±4.8 U/L on day 30, GGT from 14.9±1.6 to 12.4±1.2 U/L, and albumin increased from 35.9±3.2 to 40.5±3.9 g/L. ApoE decreased from 26.2±1.2 to 23.2±1.2 and 21.2±1.1 mg/dL, whereas LPL increased from 25.8±0.8 to 27.0±0.8 and 30.8±0.9 ng/mL on days 10, 20, and 30, respectively. Conclusion: MKD was associated with improvement in hepatobiliary, metabolic, inflammatory, and lipoprotein-related indices in experimental MetS. ApoE and LPL showed clear time-dependent responses and warrant further investigation as research indicators of lipoprotein metabolic changes.

Metabolic syndrome, modified ketogenic diet, lipoprotein lipase

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