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Diabetes Care Symposium

CV Protection in the EMPA-REG OUTCOME Trial: A “Thrifty Substrate” Hypothesis

  1. Ele Ferrannini1⇑,
  2. Michael Mark2 and
  3. Eric Mayoux2
  1. 1CNR Institute of Clinical Physiology, Pisa, Italy
  2. 2Cardiometabolic Disease Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
  1. Corresponding author: Ele Ferrannini, ferranni{at}ifc.cnr.it.
  1. E.F. and E.M. contributed equally to this study.

Diabetes Care 2016 Jul; 39(7): 1108-1114. https://doi.org/10.2337/dc16-0330
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Abstract

The striking and unexpected relative risk reductions in cardiovascular (CV) mortality (38%), hospitalization for heart failure (35%), and death from any cause (32%) observed in the EMPA-REG OUTCOME trial using an inhibitor of sodium–glucose cotransporter 2 (SGLT2) in patients with type 2 diabetes and high CV risk have raised the possibility that mechanisms other than those observed in the trial—modest improvement in glycemic control, small decrease in body weight, and persistent reductions in blood pressure and uric acid level—may be at play. We hypothesize that under conditions of mild, persistent hyperketonemia, such as those that prevail during treatment with SGLT2 inhibitors, β-hydroxybutyrate is freely taken up by the heart (among other organs) and oxidized in preference to fatty acids. This fuel selection improves the transduction of oxygen consumption into work efficiency at the mitochondrial level. In addition, the hemoconcentration that typically follows SGLT2 inhibition enhances oxygen release to the tissues, thereby establishing a powerful synergy with the metabolic substrate shift. These mechanisms would cooperate with other SGLT2 inhibition–induced changes (chiefly, enhanced diuresis and reduced blood pressure) to achieve the degree of cardioprotection revealed in the EMPA-REG OUTCOME trial. This hypothesis opens up new lines of investigation into the pathogenesis and treatment of diabetic and nondiabetic heart disease.

Introduction

First among cardiovascular (CV) end point trials of glucose-lowering agents (1), the EMPA-REG OUTCOME trial—using 10 or 25 mg/day sodium–glucose cotransporter 2 (SGLT2) inhibitor empagliflozin against placebo in 7,020 patients with type 2 diabetes (T2D) who were at increased CV risk—reported a 14% reduction in major CV events and marked relative risk reductions in CV mortality (38%), hospitalization for heart failure (35%), and death from any cause (32%) over a median time period of 2.6 years (2). Of note, all the pathologic categories of CV death (ischemic, pump failure, arrhythmic, embolic) contributed to the overall reduction in CV death in a patient cohort well treated with the use of renin-angiotensin-aldosterone inhibitors, statins, and acetylsalicylic acid. Furthermore, separation of the cumulative incidence functions between pooled-dose groups and placebo was already evident months after randomization. This unusual time course and the discrepancy between the relative risk reduction of the primary end point (nonfatal myocardial infarction, stroke, and CV mortality) and CV mortality itself suggests that active treatment affected case fatality rates more than event rates. In other words, empagliflozin treatment appeared mostly to rescue patients from impending cardiac decompensation. This interpretation is supported by the recent post hoc analyses of heart failure, documenting a large benefit in first and recurrent heart failure hospitalization across virtually every patient subgroup (3). Despite the fact that the diagnosis of heart failure was based on investigator reporting, this outcome of the EMPA-REG OUTCOME trial stands out against the recognized lack of evidence on the safety or efficacy of glucose-lowering drugs in patients with heart failure (4,5); indeed, a risk signal of incident heart failure after treatment with saxagliptin emerged from the SAVOR-TIMI trial (1).

As expected from previous clinical studies, in the EMPA-REG OUTCOME trial the difference in glycemic control between the treatment and placebo arms (with HbA1c averaging 0.54–0.60% at 12 weeks and 0.24–0.36% at study end) was accompanied by a small decrease in body weight and persistent reductions in blood pressure and uric acid level. Ahead of the study end, the EMPA-REG OUTCOME trial investigators themselves had outlined additional risk factors that the use of SGLT2 inhibitors influences positively: visceral adiposity, hyperinsulinemia, arterial stiffness, albuminuria, and oxidative stress (6). However, isolated reductions in HbA1c level, body weight, or uricemia of the degree seen in the trial have been generally reputed to be insufficient to explain the outcome (7–11). For example, a meta-analysis of macrovascular outcomes in intensive glucose control trials (12) reported a 9% reduction in major CV events for an average HbA1c reduction of 0.7%, but no significant reduction in CV or all-cause mortality. By their mode of action, SGLT2 inhibitors induce natriuresis and osmotic diuresis (13,14) and a drop in systolic and diastolic blood pressure levels (2); indeed, these effects have been hypothesized to play a pivotal role in the CV benefit shown by the EMPA-REG OUTCOME trial (10,11), especially during the early weeks of treatment when the systolic blood pressure gradient between the arms was largest (5 mmHg) (10). Clearly, such hemodynamic changes can be beneficial, particularly in patients with high CV risk, insofar as a reduced blood volume lowers the preload and a reduced blood pressure lowers the postload burden to the heart. There remain, however, inconsistencies between EMPA-REG OUTCOME trial outcomes and the CV benefit profile of antihypertensive and diuretic therapy. For example, a recent systematic review of blood pressure lowering in T2D patients (15) reported significant reductions in major CV events (including stroke), but smaller reductions in heart failure and mortality associated with a 10 mmHg decrease in systolic blood pressure. Likewise, in systematic meta-analyses (16,17), diuretic agents appear to be associated with a smaller (∼20%) reduction in CV mortality than that seen in the EMPA-REG OUTCOME trial and a clear risk reduction in stroke, which was not observed in the EMPA-REG OUTCOME trial. In a recent trial (18), the use of the mineralocorticoid receptor antagonist eplerenone in patients with systolic heart failure resulted in a reduction in hospitalization for heart failure similar in size and time course to the corresponding outcome in the EMPA-REG OUTCOME trial. The eplerenone-treated patients, however, did not have diabetes, were selected on the basis of high levels of B-type natriuretic peptide (BNP) and N-terminal pro-BNP, and the trial outcome showed no protection against nonfatal myocardial infarction or stroke. The EMPA-REG OUTCOME trial cohort (2) was composed of older patients with long-standing T2D whose heart failure, when reported, was not characterized either for ejection fraction or levels of natriuretic peptides. Also, most patients in the EMPA-REG OUTCOME trial were being treated with antihypertensive drugs, including diuretic agents, so SGLT2 inhibition conferred a benefit for heart failure above and beyond antihypertensive treatment. Interestingly, in a small, short-term (12-week) mechanistic study in T2D patients (19), treatment with dapagliflozin (another selective SGLT2 inhibitor) resulted in a smaller reduction in blood pressure than did treatment with a comparator diuretic (25 mg hydrochlorothiazide), but also in a 7% decrease in plasma volume (as directly measured with the use of 125I-labeled albumin) and some increment in N-terminal pro-BNP levels, neither of which were observed with the treatment with the diuretic agent. Thiazide diuretic agents decrease plasma volume only transiently, whereas in the EMPA-REG OUTCOME trial the observed increase in hematocrit persisted for the entire duration of the trial (20).

Collectively, these considerations suggest that other mechanisms triggered by SGLT2 inhibition may contribute to the CV outcomes of the EMPA-REG OUTCOME trial.

Hypothesis

Raised circulating levels of β-hydroxybutyrate offered significant cardioprotection to the high-risk diabetes patients in the trial.

Rationale

In diet-induced obese rats treated with dapagliflozin (21), ipragliflozin (22), or tofogliflozin (23), lipolysis is accelerated and circulating ketone body levels are increased, especially in the fasting state or when animals are fed in pairs. In patients with T2D, empagliflozin-induced glycosuria lowers plasma glucose and insulin levels and raises fasting and postmeal glucagon concentrations. The subtraction of large amounts of glucose from the glucose pool, coupled with the dual hormonal changes, results in a 25% restriction of glucose utilization, and a concomitant increase in lipid mobilization and usage for energy production (24). Under conditions of reduced portal insulin-to-glucagon ratio, the increased delivery of free fatty acids (FFAs) to the liver stimulates ketogenesis (25), resulting in a metabolic condition resembling a prolonged fast (26). In well-controlled Caucasian patients with T2D who were receiving stable doses of metformin or were drug-naive (27), a 4-week course of treatment with 25 mg empagliflozin was associated with raised fasting and postmeal circulating FFA and glycerol levels, indicating enhanced lipolysis. Concomitantly, both fasting and postmeal plasma β-hydroxybutyrate concentrations were increased twofold to threefold; these changes were similar in time course, though attenuated in extent, in a group of nondiabetic volunteers receiving the drug. Similar results have been reported in Japanese patients with T2D with the use of empagliflozin, tofogliflozin, luseogliflozin, or canagliflozin (28–32). For example, in a 24-week phase III study of drug-naive patients with T2D (32), plasma ketones rose dose dependently with the administration of 100 or 200 mg canagliflozin versus placebo throughout the study period. Of note, though mean plasma ketone levels are only modestly elevated, in a sizeable proportion of subjects they rise into the millimolar range (27–32), particularly in the more insulinopenic patients (27).

Circulating β-hydroxybutyrate is taken up (through the monocarboxylate transporter, which also transports pyruvate) in proportion to its plasma concentration into most organs, including heart, brain, and kidney, by a saturable transport mechanism (33). In humans, β-hydroxybutyrate uptake by forearm tissues is not influenced by local hyperinsulinemia (34) (Fig. 1), and exogenous β-hydroxybutyrate infusion does not interfere with insulin-mediated glucose utilization (35). Thus, β-hydroxybutyrate transport is insulin independent. In the fasting state, β-hydroxybutyrate is taken up by the human heart, along with glucose, lactate, pyruvate, glycerol, and FFA, with the highest avidity per unit mass among body tissues and with a fractional extraction (∼40%) comparable to that of pyruvate and far higher than that of glucose (∼2%) or FFA (15–20%) (36) (Fig. 2). By combining mass uptake (∼10 µmol/min) with the heat of combustion (Table 1), it can be calculated that in the overnight fasted state β-hydroxybutyrate contributes 15% of resting cardiac energy expenditure compared with 45% of FFAs and 8% of glucose/lactate/pyruvate. When the rate pressure product is increased by incremental atrial pacing (Fig. 3), the fractional extraction of β-hydroxybutyrate remains high at ∼40%, thereby continuing to support external cardiac work (37).

Figure 1
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Figure 1

Fractional exchange of substrates by the human forearm under basal conditions and during local physiological hyperinsulinemia. Note the insulin-induced increased net release of lactate and the switch from net uptake to net release of pyruvate in the face of a constant extraction of β-hydroxybutyrate. Data were recalculated from the study by Natali et al. (34).

Figure 2
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Figure 2

Fractional extraction of substrates by the human heart under basal (overnight fast) and systemic hyperinsulinemia (euglycemic-hyperinsulinemic clamp). Note the increased net extraction of glucose, lactate, and pyruvate in the face of a marked reduction in the net extraction of FFA and β-hydroxybutyrate (due to insulin-induced suppression of whole-body lipolysis). Data were recalculated from the study by Ferrannini et al. (36).

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Table 1

Comparative mitochondrial energetics of β-hydroxybutyrate oxidation

Figure 3
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Figure 3

β-hydroxybutyrate (β-HB) extraction by the normal human heart during graded atrial pacing. RPP, rate pressure product. Data were recalculated from the study by Camici et al. (37).

In perfused working rat hearts, β-hydroxybutyrate supplementation inhibits pyruvate oxidation by deactivating pyruvate dehydrogenase (38), mimics insulin action (39), and competes with oxidation of FFAs (possibly also by impeding their transport into cells [40]). Within the cell, after conversion to acetoacetate (catalyzed by the mitochondrial isoform of 3-hydroxy-3-methylglutaryl-CoA synthase) and breakdown to acetyl-CoA, β-hydroxybutyrate enters the tricarboxylic acid cycle (TCA) to be oxidized. By expanding the mitochondrial acetyl-CoA pool, β-hydroxybutyrate competes for entry into the TCA cycle with the acetyl-CoA originating from FFA oxidation and glucose-derived pyruvate (Fig. 4) (39,40). Thus, during fasting and starvation, β-hydroxybutyrate partially replaces glucose as a fuel, which is critical for the brain in circumstances of low glucose availability (26). Importantly, the energetics of mitochondrial β-hydroxybutyrate oxidation compares favorably with the oxidation of pyruvate (Table 1); in fact, when β-hydroxybutyrate is added to the perfusion medium of working rat hearts, the heat of combustion per unit of carbon has been calculated to be 31% increased and the oxygen cost of this energy output to be 27% decreased (41). This advantage is granted by a more efficient oxidation of the mitochondrial coenzyme Q couple and an increase in the free energy of cytosolic ATP hydrolysis. As a consequence, in the isolated working heart β-hydroxybutyrate increases external cardiac work at the same time as it reduces oxygen consumption, thereby improving cardiac efficiency by 24%. Furthermore, a persistently elevated rate of FFA oxidation generates reactive oxygen species in excess of scavenging capacity (42); the resulting oxidative stress contributes to mitochondrial damage in a range of pathologies (43). In in vitro systems, β-hydroxybutyrate has been shown to suppress oxidative stress (44) by inhibiting histone deacetylases. Finally, ketone bodies have been shown to upregulate mitochondrial biogenesis and, by stabilizing cell membrane potential, to exhibit antiarrhythmic potential (45).

Figure 4
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Figure 4

Raised circulating FFAs are taken up by the liver and metabolized via β-oxidation. Under circumstances of reduced insulin/glucagon ratio, in liver mitochondria the acetyl-CoA is condensed to form acetoacetate (AcAc, catalyzed by the mitochondrial isoform of 3-hydroxy-3-methylglutaryl synthase [mHMG-CoA]) and β-hydroxybutyrate (β-HB) (catalyzed by β-hydroxybutyrate dehydrogenase [HBD]). β-HB is then exported into the bloodstream, from which it is avidly taken up into the heart (through the monocarboxylate transporter [MCT]). In heart mitochondria, β-HB is converted to AcAc (by HBD), AcAc-CoA (catalyzed by succinyl-CoA:3-oxoacid CoA transferase [SCOT], with succinyl-CoA as the CoA donor), and finally acetyl-CoA (by mitochondrial thiolase [Th]), which then enters the TCA for oxidative phosphorylation (Ox Phos). The excess acetyl-CoA restrains (dotted lines) further generation of acetyl-CoA from pyruvate (by inhibiting pyruvate dehydrogenase [PDH]) and from β-oxidation of fatty acids. Ketone body oxidation results in a more efficient oxidation of the mitochondrial coenzyme Q couple and an increase in the free energy of cytosolic ATP hydrolysis. The increase in hematocrit contributes to the improvement in cardiac efficiency by releasing more oxygen (O2) to the muscle.

In the fed state, as insulin restrains lipolysis and stimulates glucose oxidation, the circulating concentrations of β-hydroxybutyrate decline along with FFA flux and oxidation. In the normal human heart, systemic insulin administration at physiologic concentrations stimulates myocardial glucose uptake, both directly and by suppressing plasma FFA concentrations, without altering coronary blood flow; the uptake of β-hydroxybutyrate and its contribution to cardiac energy expenditure drop to nil (Fig. 2) (36). However, in patients with T2D (27,46) as well as in patients without diabetes with coronary artery disease (47) or stress-induced ischemia (48), whole-body and myocardial insulin-mediated glucose utilization are impaired (i.e., insulin resistance), and a larger (>80%) than normal (50–70%) proportion of energy is derived from the oxidation of fatty substrates (49). FFAs require ∼8% more oxygen than glucose to produce the same number of calories, and the external power of the left ventricle for a given oxygen consumption is higher when rates of fatty acid β-oxidation are low relative to glucose and lactate oxidation (50). This coupling between substrate selection and mechanical efficiency is especially relevant to heart failure, regardless of its nature (ischemic or nonischemic) and functional manifestation (reduced or preserved ejection fraction) (51). Whether primarily or secondary to systemic changes induced by cardiac failure itself (e.g., adrenergic activation [47]), the failing heart is an “engine out of fuel” (52), especially when the energy demand increases, such as it does during exercise. Indeed, most kinds of cardiac injury—ischemic, myopathic, and reperfusion injury (53)—converge on insufficient mitochondrial energy output and contractile failure as the basic mechanism. Enhancing oxygen use and mechanical efficiency through the long-term provision of an energetically thrifty substrate should therefore benefit most conditions of extensive CV damage in a relatively short time frame, precisely as was the case in the EMPA-REG OUTCOME trial. In this context, β-hydroxybutyrate can be viewed as a constitutive mitochondrial helper, just as is its closest kin of energetics, pyruvate (54,55) (Table 1). Of note is that, in a mouse model of heart failure, metabolite signatures of fatty acid oxidation are reduced, whereas signatures of the oxidation of ketone bodies (e.g., β-hydroxybutyrate dehydrogenase) are increased (56). Furthermore, in patients with heart failure, the use of circulating ketones is impaired by >50% in skeletal muscle but is preserved in myocardial tissues (57). Finally, in a study of myocardial tissue obtained from patients with advanced heart failure at the time of cardiac transplantation (58), levels of acyl-CoAs were reduced and those of acetyl-CoA (and succinyl-CoA:3-oxoacid CoA transferase expression) were increased, as predicted by the metabolic sequence sketched in Fig. 4. Thus, the failing heart attempts to cope with the increased energy expenditure (59) by turning to ketone use at the expense of fatty acid use (60).

A contributing factor to the CV outcomes of the EMPA-REG OUTCOME trial could be represented by an increased delivery of oxygen to tissues. In fact, SGLT2 inhibitors cause an increase in hematocrit (61), which in the EMPA-REG OUTCOME trial averaged 5% in absolute values, and 11% in percentage points (2). This change likely reflects the hemoconcentration associated with the diuretic effect. However, preliminary results in patients with T2D who were receiving treatment with dapagliflozin (19) have shown that red blood cell mass (as measured by 51Cr-labeled erythrocytes) was expanded by ∼6%, a change that was preceded by a transient increase in erythropoietin concentrations and reticulocyte count. Thus, the observed increase in hematocrit might result in part from the stimulation of erythropoiesis, an intriguing possibility that awaits confirmation. Interestingly, the blood volume contraction was not associated with a significant increase in heart rate (2), suggesting that cardiac output was maintained at least at pretreatment levels. A higher hematocrit for the same blood flow is expected to deliver more oxygen to tissues (62). In quantitative terms, experiments in hamsters transfused with packed red blood cells (63) demonstrate that short-term increments in the hematocrit (up to ∼10%) induce a 20% rise in oxygen delivery to tissues, coupled with a 10% drop in arterial blood pressure and an increase in cardiac output. In patients (including patients with diabetes) with decompensated heart failure and renal dysfunction, hemoconcentration induced with very high doses of a loop diuretic has been associated with a substantially improved survival time despite the deterioration of renal function (64–67).

Caveats

The metabolic mechanism laid out here is basic, and as such it should apply across organs (foremost, the kidney and the brain) and pathologies (ischemic and nonischemic). However, at present crucial information is missing. Thus, we do not know 1) the dose-response relationship between raised ketone bodies and cardiac function in humans, 2) the time course of hyperketonemia during SGLT2 inhibitor treatment, and 3) the impact of other medications. For instance, the combination of an SGLT2 inhibitor with glucose-lowering agents that stimulate insulin secretion (sulfonylureas, dipeptidyl peptidase-4 inhibitors, and glucagon-like peptide 1 receptor agonists) or with exogenous insulin itself may quench or obliterate the glucagon and/or the ketone response. Furthermore, our hypothesis posits that the combination of improved oxygen use/supply with sodium/volume reduction should work best toward heart failure and organ ischemia (as well as arrhythmias), but in the EMPA-REG OUTCOME trial these end points were affected differentially in size and, possibly, in time course (2). Thus, the incidence of stroke was, if anything, numerically higher in the treatment arm than in the placebo arm (hazard ratio 1.24 [95% CI 0.92–1.67], P = 0.16), although death from stroke was recorded in 0.34% of treated patients versus 0.47% of placebo patients, and transient ischemic attacks were recorded in 0.8% of treated patients versus 1.0% of placebo participants. Given the small number of these latter events, a satisfactory explanation is not at hand, but it is theoretically possible that in vulnerable patients the increased blood viscosity associated with hemoconcentration may play a role. More adjudicated events and/or a longer trial duration and better definition of end points (e.g., type of heart failure), as well as measures of circulating substrates (e.g., β-hydroxybutyrate) and biomarkers (e.g., natriuretic peptides), would be needed to refine the quantitative aspects of any hypothesis. We hope that ongoing CV outcomes trials with other SGLT2 inhibitors (1) will provide additional information on these important issues.

Starting from the evolutionary role of ketosis (26), other biology of ketone bodies (e.g., their effects on cardiac remodeling, oxidative stress, and mitochondrial biogenesis [42–45]) has generated some enthusiasm for their therapeutic exploitation (68–70). Low-carbohydrate ketogenic diets are still widely used, mainly for weight loss, but their long-term impact on CV function is still uncertain and controversial (71). In patients with type 1 diabetes or insulin-treated patients with T2D who are receiving therapy with SGLT2 inhibitors, inappropriate reductions in exogenous insulin administration or intercurrent illness may precipitate episodes of nonhyperglycemic ketoacidosis (72). It is conceivable that the overall physiological impact of ketone bodies follows an inverted U-shaped curve, whereby mild elevations are beneficial, but higher levels may be harmful. According to the present evidence, treatment with SGLT2 inhibitors appears to superimpose intermittent mild hyperketonemia on an otherwise normal daily pattern of fast/feeding, with consistent but limited restriction of carbohydrate usage (24). More drastic changes in circulating ketone levels, carbohydrate availability, and fat composition may be counterproductive. Above all, it should not be forgotten that the cardioprotection of the EMPA-REG OUTCOME trial was seen in a cohort of patients with T2D who were at high CV risk.

Future Studies

A viable hypothesis should be not just plausible but verifiable. To this end, the presence, amount, and time course of SGLT2-induced ketonemia could be measured and related to cardiac outcomes in adequately powered clinical studies in patients with T2D. Short-term, low-rate β-hydroxybutyrate infusions could be used in hospital settings to test their effects on metabolic and functional parameters in patients with decompensated heart failure (59–63). The failing heart is insulin resistant (46) (Fig. 5) because of increased adrenergic tone and the release of natriuretic peptides and inflammatory molecules (73). Furthermore, there is evidence that myocardial insulin resistance is an independent risk factor for mortality in stable patients with chronic heart failure (74). Also, myocardial insulin resistance is associated with a mismatch between insulin-mediated glucose uptake and myocardial blood flow, possibly as a result of remodeling (75). However, we do not know whether reducing myocardial insulin resistance would restore contractile function and improve prognosis. Functional studies (three-dimensional echocardiography and magnetic resonance spectroscopy) and imaging studies (MRI, positron emission tomography) in patients with diabetes who have a high CV risk load could be performed before and after an SGLT2 treatment course. Finally, if the thrifty substrate paradigm held up in high-risk patients, studies in patients with lower CV risk would generate clinically useful data to inform therapeutic strategies.

Figure 5
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Figure 5

Direct association between insulin-induced myocardial glucose uptake and ejection fraction in control subjects and T2D patients. Redrawn with permission from Iozzo et al. (46).

Summary

The hypothesis posits that, under conditions of mild but persistent hyperketonemia—such as those that prevail during treatment with SGLT2 inhibitors—β-hydroxybutyrate is freely taken up by the heart and oxidized in preference to fatty acids. This substrate selection improves the transduction of oxygen consumption into work efficiency in the endangered myocardium (and may also improve metabolic status and function of other organs, mainly the kidney). This mechanism should cooperate with other SGLT2-induced changes (reduced blood pressure [10] and enhanced diuresis [11]) to achieve the degree of cardioprotection revealed by the EMPA-REG OUTCOME trial. In addition, enhanced oxygen release to the myocardium through hemoconcentration would be in powerful synergy with the substrate shift.

Article Information

Funding. This work was aided in part by the Italian Ministry of Education, University, and Research (grant #2010329EKE).

Duality of Interest. E.F. has been a speaker and consultant for Merck Sharp & Dohme, Sanofi, Eli Lilly and Company, Boehringer Ingelheim, Johnson & Johnson, and AstraZeneca. M.M. and E.M. are employees of Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany. No other potential conflicts of interest relevant to this article were reported.

Prior Presentation. Parts of this article were presented at the 76th Scientific Sessions of the American Diabetes Association, New Orleans, LA, 10–14 June 2016.

  • Received February 16, 2016.
  • Accepted March 28, 2016.
  • © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

References

  1. ↵
    1. Ferrannini E,
    2. DeFronzo RA
    . Impact of glucose-lowering drugs on cardiovasculare disease in type 2 diabetes. Eur Heart J 2015;36:2288–2296
    OpenUrlAbstract/FREE Full Text
  2. ↵
    1. Zinman B,
    2. Wanner C,
    3. Lachin JM, et al.; EMPA-REG OUTCOME Investigators
    . Empagliflozin, cardiovascular outcomes, and mortality in type 2 diabetes. N Engl J Med 2015;373:2117–2128pmid:26378978
    OpenUrlCrossRefPubMed
  3. ↵
    1. Fitchett D,
    2. Zinman B,
    3. Wanner C, et al.; EMPA-REG OUTCOME trial investigators
    . Heart failure outcomes with empagliflozin in patients with type 2 diabetes at high cardiovascular risk: results of the EMPA-REG OUTCOME trial. Eur Heart J. 26 January 2016 [Epub ahead of print]. DOI: 10.1093/eurheartj/ehv728pmid:26819227
    OpenUrlAbstract/FREE Full Text
  4. ↵
    1. McMurray JJ,
    2. Adamopoulos S,
    3. Anker SD, et al.; Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 of the European Society of Cardiology; ESC Committee for Practice Guidelines
    . ESC guidelines for the diagnosis and treatment of acute and chronic heart failure 2012: The Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association (HFA) of the ESC. Eur J Heart Fail 2012;14:803–869pmid:22828712
    OpenUrlCrossRefPubMed
  5. ↵
    1. Rydén L,
    2. Grant PJ,
    3. Anker SD, et al.; Authors/Task Force Members; ESC Committee for Practice Guidelines (CPG); Document Reviewers
    . ESC Guidelines on diabetes, pre-diabetes, and cardiovascular diseases developed in collaboration with the EASD: the Task Force on diabetes, pre-diabetes, and cardiovascular diseases of the European Society of Cardiology (ESC) and developed in collaboration with the European Association for the Study of Diabetes (EASD). Eur Heart J 2013;34:3035–3087pmid:23996285
    OpenUrlFREE Full Text
  6. ↵
    1. Inzucchi SE,
    2. Zinman B,
    3. Wanner C, et al
    . SGLT-2 inhibitors and cardiovascular risk: proposed pathways and review of ongoing outcome trials. Diab Vasc Dis Res 2015;12:90–100pmid:25589482
    OpenUrlAbstract/FREE Full Text
  7. ↵
    1. Muskiet MHA,
    2. van Raalte DH,
    3. van Bommel E,
    4. Smits MM,
    5. Tonneijck L
    . Understanding EMPA-REG OUTCOME. Lancet Diabetes Endocrinol 2015;3:928–929pmid:26590679
    OpenUrlCrossRefPubMed
    1. Ceriello A,
    2. Genovese S,
    3. Mannucci E,
    4. Gronda E
    . Understanding EMPA-REG OUTCOME. Lancet Diabetes Endocrinol 2015;3:929–930pmid:26590680
    OpenUrlCrossRefPubMed
    1. Gilbert RE,
    2. Connelly KA
    . Understanding EMPA-REG OUTCOME. Lancet Diabetes Endocrinol 2015;3:930–931pmid:26590681
    OpenUrlCrossRefPubMed
  8. ↵
    1. DeFronzo RA
    . The EMPA-REG study: what has it told us? A diabetologist’s perspective. J Diabetes Complications 2016;30:1–2pmid:26541076
    OpenUrlCrossRefPubMed
  9. ↵
    1. McMurray J
    . EMPA-REG - the “diuretic hypothesis”. J Diabetes Complications 2016;30:3–4pmid:26597600
    OpenUrlCrossRefPubMed
  10. ↵
    1. Turnbull FM,
    2. Abraira C,
    3. Anderson RJ, et al.; Control Group
    . Intensive glucose control and macrovascular outcomes in type 2 diabetes. Diabetologia 2009;52:2288–2298pmid:19655124
    OpenUrlCrossRefPubMedWeb of Science
  11. ↵
    1. Komoroski B,
    2. Vachharajani N,
    3. Feng Y,
    4. Li L,
    5. Kornhauser D,
    6. Pfister M
    . Dapagliflozin, a novel, selective SGLT2 inhibitor, improved glycemic control over 2 weeks in patients with type 2 diabetes mellitus. Clin Pharmacol Ther 2009;85:513–519pmid:19129749
    OpenUrlCrossRefPubMedWeb of Science
  12. ↵
    1. Cherney DZ,
    2. Perkins BA,
    3. Soleymanlou N, et al
    . Renal hemodynamic effect of sodium-glucose cotransporter 2 inhibition in patients with type 1 diabetes mellitus. Circulation 2014;129:587–597pmid:24334175
    OpenUrlAbstract/FREE Full Text
  13. ↵
    1. Emdin CA,
    2. Rahimi K,
    3. Neal B,
    4. Callender T,
    5. Perkovic V,
    6. Patel A
    . Blood pressure lowering in type 2 diabetes: a systematic review and meta-analysis. JAMA 2015;313:603–615pmid:25668264
    OpenUrlCrossRefPubMed
  14. ↵
    1. Psaty BM,
    2. Lumley T,
    3. Furberg CD, et al
    . Health outcomes associated with various antihypertensive therapies used as first-line agents: a network meta-analysis. JAMA 2003;289:2534–2544pmid:12759325
    OpenUrlCrossRefPubMedWeb of Science
  15. ↵
    1. Olde Engberink RH,
    2. Frenkel WJ,
    3. van den Bogaard B,
    4. Brewster LM,
    5. Vogt L,
    6. van den Born BJ
    . Effects of thiazide-type and thiazide-like diuretics on cardiovascular events and mortality: systematic review and meta-analysis. Hypertension 2015;65:1033–1040pmid:25733241
    OpenUrlCrossRefPubMed
  16. ↵
    1. Zannad F,
    2. McMurray JJ,
    3. Krum H, et al.; EMPHASIS-HF Study Group
    . Eplerenone in patients with systolic heart failure and mild symptoms. N Engl J Med 2011;364:11–21pmid:21073363
    OpenUrlCrossRefPubMedWeb of Science
  17. ↵
    1. Lambers Heerspink HJ,
    2. de Zeeuw D,
    3. Wie L,
    4. Leslie B,
    5. List J
    . Dapagliflozin a glucose-regulating drug with diuretic properties in subjects with type 2 diabetes. Diabetes Obes Metab 2013;15:853–862pmid:23668478
    OpenUrlCrossRefPubMedWeb of Science
  18. ↵
    1. Roush GC,
    2. Kaur R,
    3. Ernst ME
    . Diuretics: a review and update. J Cardiovasc Pharmacol Ther 2014;19:5–13pmid:24243991
    OpenUrlAbstract/FREE Full Text
  19. ↵
    1. Devenny JJ,
    2. Godonis HE,
    3. Harvey SJ,
    4. Rooney S,
    5. Cullen MJ,
    6. Pelleymounter MA
    . Weight loss induced by chronic dapagliflozin treatment is attenuated by compensatory hyperphagia in diet-induced obese (DIO) rats. Obesity (Silver Spring) 2012;20:1645–1652pmid:22402735
    OpenUrlCrossRefPubMed
  20. ↵
    1. Yokono M,
    2. Takasu T,
    3. Hayashizaki Y, et al
    . SGLT2 selective inhibitor ipragliflozin reduces body fat mass by increasing fatty acid oxidation in high-fat diet-induced obese rats. Eur J Pharmacol 2014;727:66–74pmid:24486393
    OpenUrlCrossRefPubMed
  21. ↵
    1. Suzuki M,
    2. Takeda M,
    3. Kito A, et al
    . Tofogliflozin, a sodium/glucose cotransporter 2 inhibitor, attenuates body weight gain and fat accumulation in diabetic and obese animal models. Nutr Diabetes 2014;4:e125pmid:25000147
    OpenUrlCrossRefPubMed
  22. ↵
    1. Ferrannini E,
    2. Muscelli E,
    3. Frascerra S, et al
    . Metabolic response to sodium-glucose cotransporter 2 inhibition in type 2 diabetic patients. J Clin Invest 2014;124:499–508pmid:24463454
    OpenUrlCrossRefPubMedWeb of Science
  23. ↵
    1. McGarry JD,
    2. Foster DW
    . Regulation of hepatic fatty acid oxidation and ketone body production. Annu Rev Biochem 1980;49:395–420pmid:6157353
    OpenUrlCrossRefPubMedWeb of Science
  24. ↵
    1. Cahill GF Jr
    . Fuel metabolism in starvation. Annu Rev Nutr 2006;26:1–22pmid:16848698
    OpenUrlCrossRefPubMedWeb of Science
  25. ↵
    1. Ferrannini E,
    2. Baldi S,
    3. Frascerra S, et al
    . Shift to fatty substrates utilization in response to sodium-glucose co-transporter-2 inhibition in nondiabetic subjects and type 2 diabetic patients. Diabetes. 9 February 2016 [Epub ahead of print]. DOI: 10.2337/db15-1356pmid:26861783
    OpenUrlAbstract/FREE Full Text
  26. ↵
    1. Nishimura R,
    2. Tanaka Y,
    3. Koiwai K, et al
    . Effect of empagliflozin monotherapy on postprandial glucose and 24-hour glucose variability in Japanese patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled, 4-week study. Cardiovasc Diabetol 2015;14:11pmid:25633683
    OpenUrlCrossRefPubMed
    1. Nishimura R,
    2. Osonoi T,
    3. Kanada S, et al
    . Effects of luseogliflozin, a sodium-glucose co-transporter 2 inhibitor, on 24-h glucose variability assessed by continuous glucose monitoring in Japanese patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled, crossover study. Diabetes Obes Metab 2015;17:800–804pmid:25930989
    OpenUrlCrossRefPubMed
    1. Nishimura R,
    2. Omiya H,
    3. Sugio K,
    4. Ubukata M,
    5. Sakai S,
    6. Samukawa Y
    . The sodium-glucose cotransporter 2 inhibitor luseogliflozin improves glycaemic control assessed by continuous glucose monitoring even on a low-carbohydrate diet. Diabetes Obes Metab. 6 December 2015 [Epub ahead of print]. DOI: 10.1111/dom.12611pmid:26639943
    OpenUrlCrossRefPubMed
    1. Ikeda S,
    2. Takano Y,
    3. Cynshi O, et al
    . A novel and selective sodium-glucose cotransporter-2 inhibitor, tofogliflozin, improves glycaemic control and lowers body weight in patients with type 2 diabetes mellitus. Diabetes Obes Metab 2015;17:984–993pmid:26179482
    OpenUrlCrossRefPubMed
  27. ↵
    1. Inagaki N,
    2. Kondo K,
    3. Yoshinari T,
    4. Takahashi N,
    5. Susuta Y,
    6. Kuki H
    . Efficacy and safety of canagliflozin monotherapy in Japanese patients with type 2 diabetes inadequately controlled with diet and exercise: a 24-week, randomized, double-blind, placebo-controlled, phase III study. Expert Opin Pharmacother 2014;15:1501–1515pmid:25010793
    OpenUrlCrossRefPubMed
  28. ↵
    1. Balasse EO,
    2. Féry F
    . Ketone body production and disposal: effects of fasting, diabetes, and exercise. Diabetes Metab Rev 1989;5:247–270pmid:2656155
    OpenUrlCrossRefPubMedWeb of Science
  29. ↵
    1. Natali A,
    2. Buzzigoli G,
    3. Taddei S, et al
    . Effects of insulin on hemodynamics and metabolism in human forearm. Diabetes 1990;39:490–500pmid:2180759
    OpenUrlAbstract/FREE Full Text
  30. ↵
    1. Bratusch-Marrain PR,
    2. DeFronzo RA
    . Failure of hyperketonemia to alter basal and insulin-mediated glucose metabolism in man. Horm Metab Res 1986;18:185–189pmid:3516834
    OpenUrlCrossRefPubMed
  31. ↵
    1. Ferrannini E,
    2. Santoro D,
    3. Bonadonna R,
    4. Natali A,
    5. Parodi O,
    6. Camici PG
    . Metabolic and hemodynamic effects of insulin on human hearts. Am J Physiol 1993;264:E308–E315pmid:8447398
    OpenUrlPubMed
  32. ↵
    1. Camici PG,
    2. Marraccini P,
    3. Lorenzoni R, et al
    . Coronary hemodynamics and myocardial metabolism in patients with syndrome X: response to pacing stress. J Am Coll Cardiol 1991;17:1461–1470pmid:2033177
    OpenUrlCrossRefPubMedWeb of Science
  33. ↵
    1. Garland PB,
    2. Newsholme EA,
    3. Randle PJ
    . Regulation of glucose uptake by muscle. 9. Effects of fatty acids and ketone bodies, and of alloxan-diabetes and starvation, on pyruvate metabolism and on lactate-pyruvate and L-glycerol 3-phosphate-dihydroxyacetone phosphate concentration ratios in rat heart and rat diaphragm muscles. Biochem J 1964;93:665–678pmid:4284560
    OpenUrlFREE Full Text
  34. ↵
    1. Kashiwaya Y,
    2. King MT,
    3. Veech RL
    . Substrate signaling by insulin: a ketone bodies ratio mimics insulin action in heart. Am J Cardiol 1997;80:50A–64Apmid:9293956
    OpenUrlCrossRefPubMed
  35. ↵
    1. Stanley WC,
    2. Meadows SR,
    3. Kivilo KM,
    4. Roth BA,
    5. Lopaschuk GD
    . β-Hydroxybutyrate inhibits myocardial fatty acid oxidation in vivo independent of changes in malonyl-CoA content. Am J Physiol Heart Circ Physiol 2003;285:H1626–H1631pmid:12969881
    OpenUrlAbstract/FREE Full Text
  36. ↵
    1. Sato K,
    2. Kashiwaya Y,
    3. Keon CA, et al
    . Insulin, ketone bodies, and mitochondrial energy transduction. FASEB J 1995;9:651–658pmid:7768357
    OpenUrlAbstract
  37. ↵
    1. Boveris A,
    2. Oshino N,
    3. Chance B
    . The cellular production of hydrogen peroxide. Biochem J 1972;128:617–630pmid:4404507
    OpenUrlAbstract/FREE Full Text
  38. ↵
    1. Murphy MP
    . How mitochondria produce reactive oxygen species. Biochem J 2009;417:1–13pmid:19061483
    OpenUrlAbstract/FREE Full Text
  39. ↵
    1. Shimazu T,
    2. Hirschey MD,
    3. Newman J, et al
    . Suppression of oxidative stress by β-hydroxybutyrate, an endogenous histone deacetylase inhibitor. Science 2013;339:211–214pmid:23223453
    OpenUrlAbstract/FREE Full Text
  40. ↵
    1. Cotter DG,
    2. Schugar RC,
    3. Crawford PA
    . Ketone body metabolism and cardiovascular disease. Am J Physiol Heart Circ Physiol 2013;304:H1060–H1076pmid:23396451
    OpenUrlAbstract/FREE Full Text
  41. ↵
    1. Iozzo P,
    2. Chareonthaitawee P,
    3. Dutka D,
    4. Betteridge DJ,
    5. Ferrannini E,
    6. Camici PG
    . Independent association of type 2 diabetes and coronary artery disease with myocardial insulin resistance. Diabetes 2002;51:3020–3024pmid:12351442
    OpenUrlAbstract/FREE Full Text
  42. ↵
    1. Paternostro G,
    2. Camici PG,
    3. Lammerstma AA, et al
    . Cardiac and skeletal muscle insulin resistance in patients with coronary heart disease. A study with positron emission tomography. J Clin Invest 1996;98:2094–2099pmid:8903329
    OpenUrlCrossRefPubMedWeb of Science
  43. ↵
    1. Camici P,
    2. Marraccini P,
    3. Lorenzoni R, et al
    . Metabolic markers of stress-induced myocardial ischemia. Circulation 1991;83(Suppl.):III8–III13pmid:2022052
    OpenUrlPubMed
  44. ↵
    1. Camici P,
    2. Ferrannini E,
    3. Opie LH
    . Myocardial metabolism in ischemic heart disease: basic principles and application to imaging by positron emission tomography. Prog Cardiovasc Dis 1989;32:217–238pmid:2682779
    OpenUrlCrossRefPubMedWeb of Science
  45. ↵
    1. Lopaschuk GD,
    2. Ussher JR,
    3. Folmes CDL,
    4. Jaswal JS,
    5. Stanley WC
    . Myocardial fatty acid metabolism in health and disease. Physiol Rev 2010;90:207–258pmid:20086077
    OpenUrlAbstract/FREE Full Text
  46. ↵
    1. Stanley WC,
    2. Recchia FA,
    3. Lopaschuk GD
    . Myocardial substrate metabolism in the normal and failing heart. Physiol Rev 2005;85:1093–1129pmid:15987803
    OpenUrlAbstract/FREE Full Text
  47. ↵
    1. Neubauer S
    . The failing heart—an engine out of fuel. N Engl J Med 2007;356:1140–1151pmid:17360992
    OpenUrlCrossRefPubMedWeb of Science
  48. ↵
    1. Chouchani ET,
    2. Pell VR,
    3. Gaude E, et al
    . Ischaemic accumulation of succinate controls reperfusion injury through mitochondrial ROS. Nature 2014;515:431–435pmid:25383517
    OpenUrlCrossRefPubMed
  49. ↵
    1. Tanaka M,
    2. Nishigaki Y,
    3. Fuku N,
    4. Ibi T,
    5. Sahashi K,
    6. Koga Y
    . Therapeutic potential of pyruvate therapy for mitochondrial diseases. Mitochondrion 2007;7:399–401pmid:17881297
    OpenUrlCrossRefPubMed
  50. ↵
    1. Fujii T,
    2. Nozaki F,
    3. Saito K, et al
    . Efficacy of pyruvate therapy in patients with mitochondrial disease: a semi-quantitative clinical evaluation study. Mol Genet Metab 2014;112:133–138pmid:24830361
    OpenUrlCrossRefPubMed
  51. ↵
    1. Aubert G,
    2. Martin OJ,
    3. Horton JL, et al
    . The failing heart relies on ketone bodies as a fuel. Circulation 2016;133:698–705pmid:26819376
    OpenUrlAbstract/FREE Full Text
  52. ↵
    1. Janardhan A,
    2. Chen J,
    3. Crawford PA
    . Altered systemic ketone body metabolism in advanced heart failure. Tex Heart Inst J 2011;38:533–538pmid:22163128
    OpenUrlPubMed
  53. ↵
    1. Bedi KC Jr,
    2. Snyder NW,
    3. Brandimarto J, et al
    . Evidence for intramyocardial disruption of lipid metabolism and myocardial ketone utilization in advanced human heart failure. Circulation 2016;133:706–716pmid:26819374
    OpenUrlAbstract/FREE Full Text
  54. ↵
    1. Du Z,
    2. Shen A,
    3. Huang Y, et al
    . 1H-NMR-based metabolic analysis of human serum reveals novel markers of myocardial energy expenditure in heart failure patients. PLoS One 2014;9:e88102pmid:24505394
    OpenUrlCrossRefPubMed
  55. ↵
    1. Kolwicz SC Jr,
    2. Airhart S,
    3. Tian R
    . Ketones step to the plate: a game changer for metabolic remodeling in heart failure? Circulation 2016;133:689–691pmid:26819375
    OpenUrlFREE Full Text
  56. ↵
    1. Mudaliar S,
    2. Polidori D,
    3. Zambrowicz B,
    4. Henry RR
    . Sodium-glucose cotransporter inhibitors: effects on renal and intestinal glucose transport: from bench to bedside. Diabetes Care 2015;38:2344–2353pmid:26604280
    OpenUrlAbstract/FREE Full Text
  57. ↵
    1. Testani JM,
    2. Chen J,
    3. McCauley BD,
    4. Kimmel SE,
    5. Shannon RP
    . Potential effects of aggressive decongestion during the treatment of decompensated heart failure on renal function and survival. Circulation 2010;122:265–272pmid:20606118
    OpenUrlAbstract/FREE Full Text
  58. ↵
    1. McBride BF,
    2. White CM
    . Anemia management in heart failure: a thick review of thin data. Pharmacotherapy 2004;24:757–767pmid:15222666
    OpenUrlCrossRefPubMed
  59. ↵
    1. Martini J,
    2. Tsai AG,
    3. Cabrales P,
    4. Johnson PC,
    5. Intaglietta M
    . Increased cardiac output and microvascular blood flow during mild hemoconcentration in hamster window model. Am J Physiol Heart Circ Physiol 2006;291:H310–H317pmid:16489106
    OpenUrlAbstract/FREE Full Text
    1. Mentz RJ,
    2. O’Connor CM
    . Pathophysiology and clinical evaluation of acute heart failure. Nat Rev Cardiol 2016;13:28–35pmid:26370473
    OpenUrlPubMed
    1. Greene SJ,
    2. Gheorghiade M,
    3. Vaduganathan M, et al.; EVEREST Trial investigators
    . Haemoconcentration, renal function, and post-discharge outcomes among patients hospitalized for heart failure with reduced ejection fraction: insights from the EVEREST trial. Eur J Heart Fail 2013;15:1401–1411pmid:23845795
    OpenUrlCrossRefPubMed
  60. ↵
    1. van der Meer P,
    2. Postmus D,
    3. Ponikowski P, et al
    . The predictive value of short-term changes in hemoglobin concentration in patients presenting with acute decompensated heart failure. J Am Coll Cardiol 2013;61:1973–1981pmid:23500313
    OpenUrlCrossRefPubMedWeb of Science
  61. ↵
    1. Cahill GF Jr,
    2. Veech RL
    . Ketoacids? Good medicine? Trans Am Clin Climatol Assoc 2003;114:149–161pmid:12813917
    OpenUrlPubMed
    1. Veech RL
    . The therapeutic implications of ketone bodies: the effects of ketone bodies in pathological conditions: ketosis, ketogenic diet, redox states, insulin resistance, and mitochondrial metabolism. Prostaglandins Leukot Essent Fatty Acids 2004;70:309–319pmid:14769489
    OpenUrlCrossRefPubMedWeb of Science
  62. ↵
    1. Veech RL,
    2. Chance B,
    3. Kashiwaya Y,
    4. Lardy HA,
    5. Cahill GF Jr
    . Ketone bodies, potential therapeutic uses. IUBMB Life 2001;51:241–247pmid:11569918
    OpenUrlCrossRefPubMedWeb of Science
  63. ↵
    1. Astrup A,
    2. Meinert Larsen T,
    3. Harper A
    . Atkins and other low-carbohydrate diets: hoax or an effective tool for weight loss? Lancet 2004;364:897–899pmid:15351198
    OpenUrlCrossRefPubMedWeb of Science
  64. ↵
    1. Rosenstock J,
    2. Ferrannini E
    . Euglycemic diabetic ketoacidosis: a predictable, detectable, and preventable safety concern with SGLT2 inhibitors. Diabetes Care 2015;38:1638–1642pmid:26294774
    OpenUrlFREE Full Text
  65. ↵
    1. Doehner W,
    2. Frenneaux M,
    3. Anker SD
    . Metabolic impairment in heart failure: the myocardial and systemic perspective. J Am Coll Cardiol 2014;64:1388–1400pmid:25257642
    OpenUrlCrossRefPubMed
  66. ↵
    1. Doehner W,
    2. Rauchhaus M,
    3. Ponikowski P, et al
    . Impaired insulin sensitivity as an independent risk factor for mortality in patients with stable chronic heart failure. J Am Coll Cardiol 2005;46:1019–1026pmid:16168285
    OpenUrlCrossRefPubMedWeb of Science
  67. ↵
    1. Iozzo P,
    2. Chareonthaitawee P,
    3. Rimoldi O,
    4. Betteridge DJ,
    5. Camici PG,
    6. Ferrannini E
    . Mismatch between insulin-mediated glucose uptake and blood flow in the heart of patients with type II diabetes. Diabetologia 2002;45:1404–1409pmid:12378381
    OpenUrlCrossRefPubMedWeb of Science
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CV Protection in the EMPA-REG OUTCOME Trial: A “Thrifty Substrate” Hypothesis
Ele Ferrannini, Michael Mark, Eric Mayoux
Diabetes Care Jul 2016, 39 (7) 1108-1114; DOI: 10.2337/dc16-0330

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CV Protection in the EMPA-REG OUTCOME Trial: A “Thrifty Substrate” Hypothesis
Ele Ferrannini, Michael Mark, Eric Mayoux
Diabetes Care Jul 2016, 39 (7) 1108-1114; DOI: 10.2337/dc16-0330
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