Dapagliflozin and Cholesterol Metabolism in Type 2 Diabetes (DM2)

Background: Type 2 diabetes is associated with an increased cardiovascular risk. Besides metformin, a new treatment strategy is oral SGLT2 inhibition (dapagliflozin), Although the recently published, first-in-class cardiovascular outcome trial (EMPA-REG OUTCOME) has suggested a beneficial effect on all cause cardiovascular mortality upon SGLT2 inhibition, a known (class) side effect in worsening of dyslipidemia in all DM2 patients. The investigators thus aim to dissect the effect of SGLT2 inhibition (Dapagliflozin 10mg once daily for 5 weeks) on glucose and lipid fluxes in uncomplicated DM2 subjects.

Objective: To investigate the effect of 5 weeks dapagliflozin 10 mg once daily treatment on glucose and lipid fluxes in patients with type 2 diabetes.

Study design: Single center single arm (mechanistic) intervention trial.

Study Population: Male or postmenopausal female patients with type 2 diabetes BMI > 25 kg/m2and more than 12 weeks a stable dose of metformin treatment > 1500mg, HbA1C ≥6.5% - <8.5%, FPG<13.2 mmol/l, LDL cholesterol >2.5 mmol/l, willing to switch to rosuvastatin 10mg once daily for 4 weeks, and then receive 10 mg dapagliflozin once daily orally, for 5 weeks.

Treatment: After a statin washout fase of 4 weeks, baseline cholesterol synthesis will be measured (2H3 Leucine, 2H2O deuterated water). Then, treatment with rosuvastatin 10mg for 4 weeks will be initiated after which, patients will undergo glucose (2H2enriched glucose) and lipid flux (2H3 Leucine, 2H2O deuterated water and oral 1,2,3,4-13C16 - palmitate enrichment measurements) followed by 5 weeks treatment with dapagliflozin 10mg once daily. In the final week glucose/lipid flux measurements will be repeated.

Outcome measures: The primary endpoint is effect of 5 weeks SLGT2 inhibition on LDL cholesterol synthesis in patients with DM2. Secondary endpoints are effect of SGLT2 inhibition on triglyceride and cholesterol fluxes as well as (hepatic and peripheral) insulin sensitivity and energy expenditure. Finally, effect of SGLT2 inhibition on dietary intake, liver fat content (MRI liver) and fecal microbiome will be studied at these timepoints.

Sample Size: Based on published data, the investigators expect 10% higher plasma LDL level (from 3.1 ± 0.8 to 1.7 ± 0.4 mmol/l ) upon SGLT2 inhibition in DM2. DM2 subjects have concomitant LDL- ApoB synthesis (1.8 ± 0.4 gram/day) after 4 weeks of rosuvastatin 10mg. Assuming an increase in LDL-apoB synthesis of 0.3 gram/day with SD of 0.4 and using single-sided test (with alfa of 0.05 and 85% power), the sample size needs to be 11 DM2 subjects on dapagliflozin 10mg treatment. Taking a 10% patient dropout rate, the aim is to include 12 DM2 subjects in total.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness: The risk for patients to participate in this study is minimal. All of the stable isotopes are GMP produced and analyses techniques have been previously used and published by the investigators. Also, REE and liver MRI measurements are not associated with adverse events. Both rosuvastatin and dapagliflozin have been approved by FDA/EMA and are widely prescribed. In total 470 ml blood (100 ml per lipidflux day, 90 ml per clamp day) will be drawn over period of 13 weeks (divided over 5 visits).

Inclusion criteria

• Male or postmenopausal female patients ;
• Type 2 diabetes mellitus(HbA1C ≥6.5% - <8.5%)
• At least 12 weeks of stable dose metformin treatment, FPG<13.2 mmol/l
• LDL cholesterol >2.5 mmol/l
• Willing to switch used statin to rosuvastatin 10mg once daily
• 18-75 years of age
• Ability to provide informed consent

Exclusion criteria

• History of cardiovascular event
• Smoking
• exogenous insulin use
• Creatinin clearance < 60ml/min
• Alcohol abuse (>4 units/day)
• AST or ALT elevation (>2.5x upper limit)
• Contraindication to MR scanning (i.e. pacemaker, metallic foreign body, claustrophobia)