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Published in final edited form as: Vascul Pharmacol. 2022 Jul 30;146:107093. doi: 10.1016/j.vph.2022.107093

Endothelial leptin receptor is dispensable for leptin-induced sympatho-activation and hypertension in male mice

Reem T Atawia a, Jessica L Faulkner a, Vinay Mehta a, Andrew Austin a, Coleton R Jordan a, Simone Kennard a, Eric J Belin de Chantemèle a,b,*
PMCID: PMC9561021  NIHMSID: NIHMS1840835  PMID: 35914636

Abstract

Leptin plays a crucial role in blood pressure (BP) regulation, notably in the context of obesity through central sympatho-mediated pressor effects. Leptin also relaxes arteries via endothelial (EC) leptin receptor (LepREC)- mediated increases in nitric oxide (NO) bioavailability. Herein, we investigated whether leptin-mediated increases in NO bioavailability represent a buffering mechanism against leptin-induced sympatho-activation. We tested the direct contribution of LepREC to BP regulation in physiological conditions and in response to chronic leptin infusion using mice deficient in LepREC. LepREC deficiency did not alter baseline metabolic profile nor leptin-induced reduction in adiposity and increases in energy expenditure. LepREC−/− mice demonstrated no increase in baseline BP and heart rate (HR) (MAP: LepREC+/+:94.7 ± 1.6, LepREC−/−:95.1 ± 1.8 mmHg; HR: LepREC+/+:492.4 ± 11.7, LepREC−/−:509.5 ± 13.4 bpm) nor in response to leptin (MAP, LepREC+/+:101.1 ± 1.7, LepREC−/−:101.7 ± 1.8 mmHg; HR, LepREC+/+:535.6 ± 11.1, LepREC−/−:539.3 ± 14.2 bpm). Moreover, baseline neurogenic control of BP and HR was preserved in LepREC−/− mice as well as leptin-mediated increases in sympathetic control of BP and HR and decreases in vagal tone. Remarkably, LepREC deficiency did not alter endothelium-dependent relaxation in resistance vessels, nor NO contribution to vasodilatation. Lastly, leptin induced similar increases in adrenergic contractility in mesenteric arteries from both LepREC+/+ and LepREC−/− mice. Collectively, these results demonstrate that the NO buffering effects of leptin are absent in resistance arteries and do not contribute to BP regulation. We provide further evidence that leptin-mediated hypertension involves increased vascular sympatho-activation and extend these findings by demonstrating for the first time that increased cardiac sympatho-activation and reduced vagal tone also contribute to leptin-mediated hypertension.

Keywords: Obesity, Hypertension, Autonomic control of blood pressure, Resistance artery, Nitric oxide

1. Introduction

Despite numerous health campaigns and the development of new strategies to mitigate body weight gain, the prevalence of obesity remains on a rising curve in the US with >42% adults suffering from obesity (BMI > 30) and almost 10% of them affected by severe obesity (BMI > 40). Obesity is the leading risk factor for cardiometabolic diseases and increases the risk notably of hypertension the primary contributor of cardiovascular events [1,2]. Obesity dramatically increases the secretion and plasma levels of the adipokine leptin, a key regulator of metabolic and cardiovascular function, which has been identified as a major contributor to hypertension in obese patients [3,4]. Leptin acts centrally in the hypothalamus to suppress appetite and increase energy expenditure [5,6] but also to increase sympathetic output and consequently elevate blood pressure [7–10]. Leptin receptor (LepR) expression is however not limited to the central nervous system. LepR is expressed in endothelial cells where its activation has been reported to increase nitric oxide (NO) bioavailability. However, whether leptin-mediated increases in NO bioavailability provides a buffering mechanism mitigating the central leptin-mediated sympatho-activation remains controversial [11,12]. Indeed, while it has also been shown that NO synthase inhibition enhances the hypertensive effects of leptin in rats [13–15], others reported no meaningful direct dilatory action of acute leptin administration on resistance vessels in vivo [16,17]. In addition, while several studies by our group and others have demonstrated that leptin increases NO bioavailability via activating its cognate receptor on endothelial cells in conduit arteries [12,18–21] conflicting reports indicate that leptin impairs endothelium-dependent relaxation in dog coronary arteries and promotes inflammation and oxidative stress [22–24]. Therefore, the goal of the present study is to take advantage of a novel mouse model with selective deficiency in endothelial leptin receptor to provide a better understanding of the contribution of leptin-mediated endothelial cell activation to BP regulation.

2. Material and methods

2.1. Animals

Male mice (12 week-old, C57BL/6 background) with inducible endothelial cell-specific deletion of the leptin receptor (LepREC−/−) were generated by crossing mice with loxP-flanked (flox) LepR alleles (LepR flox/flox, Jackson Laboratory) with mice expressing a Cre recombinase-estrogen receptor ERT2 fusion protein under control of the endothelial Cadherin promoter (Cdh5-CreERT2, from R. Adams, Max-Planck-Institute). At 12 weeks of age, tamoxifen (0.1 mL of a 20 mg/mL solution in corn oil) was injected intraperitoneally for 10 days to induce Cre recombinase activity. The efficiency of the protocol at selectively deleting LepR in vascular endothelial cells has been previously demonstrated [12]. All experiments were conducted 1 week following the last tamoxifen injection. All animals were housed in an American Association of Laboratory Animal Care-approved animal care facility at Augusta University. Mice were provided standard mouse chow and tap water ad libitum. All protocols were approved by Augusta University Institutional Animal Care and Use Committee (IACUC protocol #2011–0108).

2.2. Indirect calorimetry and body composition

Body composition was determined in a subset of mice using Bruker minispec LF90 TD-Nuclear magnetic resonance (NMR) analyzer. The Oxymax Comprehensive Lab Animal Monitoring System (CLAMS, Columbus Instruments, Columbus, OH) was used to measure average daily food and water consumption, respiratory exchange ratio (RER, ratio VCO2 to VO2), energy expenditure, locomotor activity and voluntary wheel counts over a 3-day period, and activity as previously described [25,26].

2.3. In vivo blood pressure measurement

In another cohort of mice, radio-telemetry transmitters were implanted to record arterial pressure and heart rate (PA-C10, Data Sciences, St Paul, MN). Following 7 days of recovery from surgery, baseline blood pressure and heart rate values were obtained at 10-min intervals for 7 days then values were recorded for 7 more days following leptin treatment. Mean, systolic and diastolic blood pressure and heart rate values were analyzed from 12-h averages for day and night as described previously [25,27].

2.4. Leptin supplementation

Animals were implanted with subcutaneous osmotic mini-pumps (ALZET, Cupertino, Calif; model 1007D, 0.5 μL/h) to infuse leptin (1 mg/kg per day, leptin CYT-351, Prospec, Rehovost, Israel) continuously for 7 days and achieve plasma leptin levels similar to that of obese individuals [12,18,28,29].

2.5. Indices of autonomic function

Indices of autonomic control of BP and heart rate (HR) were obtained by measuring BP and HR responses to injections of the ganglionic blocker Hexamethonium (1 mg/kg), the β-adrenergic receptor blocker propranolol (6 mg/kg) and of the muscarinic receptor blocker atropine (1 mg/kg), in a random order, in conscious mice instrumented for telemetry. All drugs were dissolved in saline solution (0.9% NaCl) and were given intraperitoneally 2.5 h apart of each other [25,27,28,30].

2.6. Blood, organ collection and vascular function

Mice were euthanized with isoflurane, trunk blood was collected for plasma isolation and measurement of blood glucose using an Alpha-TRAK glucometer as well as leptin using ELISA kit (EZML-82 K, Merck Millipore, Darmstadt, Germany). Additionally, 2nd order mesenteric arteries were isolated and cleaned from surrounding fat and connective tissues in ice-cold Krebs solution, and 2 mm segments were mounted on tungsten wires in a multi-channel myography system (DMT, Aarhus, Denmark) as described in [22]. Vessels were equilibrated in myograph chambers and DMT normalization module from ADInstruments was used to determine the passive tension to be applied to the segment which is equivalent to an effective active pressure above 13.3 kPa or 100 mmHg. Data were recorded and analyzed using a data acquisition system (LabChart software; AD Instruments, Colorado Springs, CO). After equilibration, arterial viability was determined with a potassium-rich solution (KCl, 80 mmol/L) until reaching maximum depolarizationinduced contractions. Concentration response curves (CRC) to phenylephrine (PE, 1 nmol/L to 100 μmol/L), acetylcholine (ACh, 1 ηmol/L to 100 μmol/L) in presence or absence of nitric oxide synthase (NOS) inhibitor; N-nitro-larginine methyl ester (L-NAME; 100 μmol/L, Sigma Aldrich, MO-USA) as well as sodium nitroprusside (SNP, 0.1 ηmol/L to 1 μmol/L) were conducted. The response to ACh and SNP is expressed as percentage of the preconstriction with PE (1 μM). The response to PE is presented as a percentage of KCl-mediated constriction [27].

2.7. Statistical analysis

All data are presented as mean ± SEM. t-test or Two-way or repeated measure Three-way analysis of variance (ANOVA) followed by Tukey post-hoc test were used to analyze data (GraphPad Prism 7; GraphPad Software Inc., La Jolla, CA). For all comparisons, P values <0.05 were considered significant.

3. Results

3.1. The metabolic effects of leptin are independent of endothelial LepR activation

As reported in Table 1, endothelial cell LepR deficiency does not alter baseline nor metabolic response to leptin. Indeed, LepREC+/+ and LepREC−/− mice exhibit similar body weight and organ weights as well as comparable blood glucose and plasma leptin levels. In addition, LepREC+/+ and LepREC−/− mice present with similar decreases in body weight, blood glucose and adipose tissue weights (VAT, SAT and BAT) in response to chronic leptin infusion, which are associated with similar reductions in food and water intake (Fig.1A and B). Leptin decreased RER and increased energy expenditure similarly in LepREC+/+ and LepREC−/− mice (Fig.1C and D) with no alterations in locomotor or voluntary wheel activity (Fig.1E and F).

Table 1.

Leptin-induced reductions in body and adipose depots masses are independent of endothelial LepR.

LepREC+/+ LepREC−/− LepREC+/++ leptin LepREC−/− + leptin Effect of Leptin Effect of genotype
Body weight (g) 28.9 ± 1.1 28.4 ± 1.0 25.4 ± 1.5 25.6 ± 0.8 p = 0.0157* p = 0.8876
Liver (mg/g) 58.4 ± 1.9 54.3 ± 2.1 48.2 ± 2.2 50.4 ± 5.8 p = 0.0522 p = 0.7768
Heart (mg/g) 6.3 ± 0.5 6.3 ± 0.3 6.7 ± 0.4 6.5 ± 0.4 p = 0.4562 p = 0.9116
Kidney (mg/g) 15.0 ± 0.5 14.2 ± 0.7 14.8 ± 0.3 13.8 ± 0.3 p = 0.6659 p = 0.1231
VAT (mg/g) 9.8 ± 2.2 7.8 ± 0.9 2.6 ± 0.6 1.7 ± 0.5 p = 0.0001**** p = 0.2626
SAT (mg/g) 6.1 ± 0.7 5.6 ± 1.1 2.5 ± 0.3 2.4 ± 0.6 p = 0.0013** p = 0.7455
BAT (mg/g) 3.5 ± 0.1 2.9 ± 0.5 2.3 ± 0.2 2.4 ± 0.5 p = 0.0599 p = 0.5798
Glucose (mg/dl) 239.3 ± 12.4 196.5 ± 25.6 144.3 ± 11.0 154.5 ± 9.0 p = 0.001** p = 0.3266
Leptin (ng/ml) 1.28 ± 0.3 1.0 ± 0.2 9.4 ± 3.5 11.2 ± 4.2 p = 0.0007*** p = 0.7592
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Tissue weight expressed per gram of body weight. Plasma glucose and leptin concentration. VAT, Visceral adipose tissue; SAT, subcutaneous adipose tissue; BAT, brown adipose tissue. Data are mean ± SEM,

*

P < 0.05,

**

p < 0.01,

***

p < 0.001 and

****

p < 0.0001 vs. baseline within the same genotype group, (N = 3–8/group).

Fig. 1.

Fig. 1.

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Leptin increased metabolic rate with no effect on locomotor activity. Quantitation of average daily food intake (A), water intake (B), Respiratory exchange ratio (RER, C), energy expenditure (D) calculated as kcal of heat produced/h/ body weight in grams, voluntary wheel activity (E) and locomotor activity (F) measured by Comprehensive Laboratory Animal Monitoring System (CLAMS). Data are presented as mean ± SEM. *P < 0.05, **p < 0.01 and ****p < 0.0001 vs. baseline within the same genotype group. (n per group: 4).

3.2. Endothelial LepR does not contribute to baseline BP regulation and BP response to leptin

In vivo radio-telemetric blood pressure monitoring revealed no effect of endothelial cell LepR deficiency on baseline BP as well as on hemodynamic responses to leptin. LepREC+/+ and LepREC−/− mice present with similar systolic (SBP) (Fig.2A–C), diastolic (DBP) (Fig.2D–F) and mean arterial pressure (MAP) (Fig.2G–I). Leptin treatment for 7 days elevated SBP, DBP and MAP to a similar extent in both LepREC−/− and LepREC+/+ mice. In both genotypes, leptin increased blood pressure significantly in the inactive (daytime) period only (Fig.2A–I) generating a reduction in the day-night blood pressures differences in both LepREC+/+ and LepREC−/− mice (Fig.3A–C) characteristic of a non-dipping hypertensive phenotype. Additionally, leptin treatment increased heart rate (HR) with no effect of endothelial leptin receptor deletion (Fig.4A–C).

Fig. 2.

Fig. 2.

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Leptin-induced hypertension is independent of endothelial leptin receptor. Circadian rhythm and quantitative analysis of systolic (SBP, A-C), diastolic (DBP, D–F), mean arterial (MAP, G-I) pressure as measured by radio-telemetry in LepREC−/− and LepREC+/+ mice at baseline and 7 days following leptin implantation. Data are presented as mean ± SEM. **p < 0.01 and ***p < 0.001vs. baseline within the same genotype group. (n per group: 11–12).

Fig. 3.

Fig. 3.

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Leptin-induced a nondipping hypertensive phenotype independent of endothelial leptin receptor. Quantitative analysis of difference between day and night SBP (A), DBP (B), MAP (C) in LepREC−/− and LepREC+/+ mice at baseline and 7 days following leptin implantation. Data are presented as mean ± SEM. ***p < 0.001 and ****p < 0.0001 vs. baseline within the same genotype group. (n per group: 11–12).

Fig. 4.

Fig. 4.

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Leptin-induced cardiac tone is independent of endothelial leptin receptor. Circadian rhythm and quantitative analysis of heart rate (A-C) measured by radio-telemetry in LepREC−/− and LepREC+/+ mice at baseline and 7 days following leptin implantation. Data are presented as mean ± SEM. **p < 0.01 vs. baseline within the same genotype group. (n per group: 11–12).

3.3. Leptin modulates cardiac autonomic nervous system activity independently of endothelial LepR

The neurogenic control of BP and HR was examined by measuring MAP and HR responses to the ganglionic blocker, hexamethonium, the β-blocker, propranolol, and the muscarinic receptor antagonist, atropine. As reported in Fig. 5, Endothelial leptin receptor deficiency had no effects on sympathetic and vagal tone responses to pharmacological stimulations. In addition, leptin treatment significantly increased MAP response to ganglionic blockade (Fig. 5A) and HR responses to propranolol (Fig. 5B) and atropine (Fig. 5C), in both LepREC−/−and LepREC+/+ mice.

Fig. 5.

Fig. 5.

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Leptin reduced cardiac vagal and increased adrenergic tone independently of EC LepR deficiency. Change in MAP in response to ganglionic blockade, hexamethonium (A), Change in HR in response to β-adrenergic blockade, propranolol (B), muscaric antagonist, atropine (C). Data are presented as mean ± SEM. *P < 0.05, **p < 0.01 vs. baseline within the same genotype group. (n per group: 4–12).

3.4. Endothelial LepR deletion does not affect vascular reactivity in resistance arteries

In order to investigate the vascular consequences of endothelial cell LepR deletion, we analyzed the vascular reactivity of mesenteric arteries from LepREC+/+ and LepREC−/− mice via wire myography. As reported in Fig. 6, endothelial cell LepR deletion did not alter endothelium-dependent (ACh, Fig.6A) or -independent (SNP, Fig.6B) relaxation nor receptor-independent (KCl, Fig.6D) or α-adrenergic receptor-mediated constriction (PE, Figs. 6E, F). Chronic leptin infusion was without effects on endothelial and smooth muscle cells-dependent relaxation in LepREC+/+ and LepREC−/− mice but specifically increased α-adrenergic contractility in both genotypes. Concentration response curves to ACh in the presence of the NO synthase inhibitor L-NAME revealed that neither endothelial cell LepR deficiency, nor chronic leptin infusion altered NO contribution to endothelium-dependent relaxation in both genotypes.

Fig. 6.

Fig. 6.

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Leptin induced vascular adrenergic tone in resistance vessels. Concentration response curves (CRC) to Acetylcholine (ACh,A) and Sodium Nitroprusside (SNP, B). CRC to ACh in the presence of L-NAME (C). Quantitation of KCl-induced vascular contractility (D) CRC to phenylephrine (PE, E) and quantitative analysis of maximum response to PE (F) expressed as percentage of KCl-induced contractility in mesenteric arteries from LepREC+/+ and LepREC−/− treated with or without leptin (1 mg/kg per day, 7 days). Data are presented as mean ± SEM. *P < 0.05 vs. baseline within the same genotype group. (n per group: 4–10).

4. Discussion

Leptin is a pleiotropic hormone which affects almost every physiological system and has been shown to play a key role in the control of blood pressure, notably in the context of obesity [31,32]. While it is currently well-established that leptin increases sympathetic activity via centrally mediated mechanisms [7–10], the role of leptin in the control of peripheral vascular resistance remains ill-defined. Previous in vitro and ex vivo studies have revealed that leptin exerts vasomotor functions and regulates vascular dilatory properties via either increases or decreases in NO bioavailability at the endothelial cell level [13,15,19,33]. This led to the proposal that leptin-mediated increases in endothelial NO bioavailability counterbalances the well-established centrally mediated leptin-induced sympatho-activation [13–15,19]. However, until the present study, no approach had been developed to systematically test the contribution of endothelial leptin signaling to BP regulation and investigate the potential buffering effects of leptin-mediated endothelium-derived increases in NO bioavailability on BP. Using a validated mouse model, in which leptin receptor (LepR) has been selectively deleted in endothelial cells [12], we reported for the first time that endothelial leptin signaling does not contribute to leptin-mediated increases in BP. Relevant to this observation are the tissue specific effects of leptin and the heterogeneity in the mechanisms of vascular relaxation between vascular beds.

Numerous studies conducted in vitro in endothelial cells in culture or ex vivo in isolated arteries have established that activation of endothelial leptin signaling increases NO bioavailability and promotes vascular relaxation through NO-dependent mechanisms [14,34]. Activation of endothelial leptin signaling has been shown to increase endothelial NO synthase activity through Akt-dependent mechanisms [19] but also to elevate bioavailable NO levels via reducing oxidative stress [12,18]. Notably, recent work by our group showed in three different mouse models including the present endothelial inducible LepR deficient mice, that activation of endothelial leptin signaling reduces NOX1-derived ROS production [12,21,35]. The groups of Hall and Frühbeck investigated the functional relevance of these ex vivo findings in terms of BP control. While measuring BP response to leptin in animals treated with the non-specific NO synthase inhibitor L-NAME they reported that acute and chronic NO synthase inhibition exacerbated the BP response to leptin, which led to the postulate that leptin derived-NO opposes the pressor effects of sympatho-activation [13,15]. Although all the latter studies have been conducted in rigorous conditions, these studies present several caveats still questioning the functional relevance of the observations. These include the nature of the study (in vitro and ex vivo), the type of the vessels studied (conductance arteries) and the use of a drug (L-NAME), which is not specific to endothelial NO synthase and which use has been associated with an activation of the renin-angiontensin-aldosterone system [36,37], increases in sympathetic tone [38,39] as well as in prostaglandins [40,41] and ROS production [42,43]. To compensate for these limitations, we selectively targeted endothelial leptin signaling and focused on resistance arteries which are the main vessels contributing to BP regulation. We reported that selective disruption in endothelial leptin signaling in LepR deficient mice has no impact on leptin-control of metabolic function, a potential confounding factor while studying BP regulation. Indeed, EC lepR deletion did not alter leptin-induced reduction in food intake and increases in energy expenditure. Moreover, both LepREC+/+ and LepREC−/− mice exhibited a similar shift in metabolic substrate from carbohydrates towards fatty acids. This is reflected by a decrease in RER which is associated with reduced fat masses due to lipids mobilization from fat stores for energy oxidation [44]. We also showed that leptin-mediated control of autonomic function is preserved in LepR EC−/−. Leptin induced a similar increase in sympathetic activity and decrease in parasympathetic tone in LepREC−/− and LepREC+/+ mice. Although we demonstrated that EC LepR deficiency increased NOX1-derived ROS production, decreased NO bioavailability and impaired endothelial-dependent relaxation in aorta [12], we found no effect of EC LepR deficiency on baseline BP or BP response to leptin. Remarkably, EC LepR deficiency did not alter endothelial function nor NO contribution to relaxation in mesenteric arteries. In combination with the data from the literature [16,17], these findings suggest that leptin-mediated increases in NO bioavailability is likely restricted to conduit arteries which relaxation is almost entirely dependent on NO and which contribution to BP regulation is minimum. Resistance vessels, in opposition to conductance arteries, play a crucial role in the regulation of BP, however, their relaxation is much less dependent on NO and involves other factors such as prostaglandins and endothelium-derived hyperpolarization factor (EDHF) [45]. Endothelium-dependent relaxation was preserved in mesenteric arteries from EC LepR deficient mice and the contribution of NO to relaxation was neither affected by EC LepR deficiency nor by chronic leptin infusion as reflected by the relaxation response curves in the presence of L-NAME. Consistent with the absence of effects of leptin on rat mesenteric and renal artery conductance [16] and the observation that leptin infusion does not relax rat hindlimb arteries [17], the preserved endothelial function in resistance arteries from EC LepR deficient mice provide an explanation for the lack of contribution of endothelial LepR to BP control. All together, these data indicate that leptin-induced endothelium-derived increases in NO bioavailability are restricted to conductance arteries and do not buffer the central pressor effects of leptin.

In addition to clarifying the role of endothelial leptin signaling in BP regulation, the present study provides additional knowledge regarding the contribution of the autonomic nervous system to BP regulation. Notably, the present work highlights the contribution of the autonomic control of heart function to BP regulation. The increased BP response to ganglionic blockade and enhanced mesenteric arteries adrenergic contractility in response to leptin infusion confirm the well-established leptin-driven increase in sympathetic activity. However, the increased and reduced heart rate responses to propranolol and atropine respectively, indicate that leptin both increases sympathetic control of heart function and reduces vagal tone. This increase in heart rate in response to leptin is consistent with the positive correlation between leptin levels and heart rate previously reported in healthy men [46] as well as with the observation that diet-induced obesity elevates heart rate while heart rate is preserved in obese leptin deficient (ob/ob) mice [20,47] . These data likely provide an additional mechanism whereby leptin elevates blood pressure in obesity and further support the concept that leptin exerts artery-type specific effects.

Another key finding of the present study is the development of a non-dipping hypertensive phenotype with leptin infusion. Non-dipping hypertension, defined as reduction in day-night blood pressure differences, is a major risk factor for cardiovascular morbidity and mortality with an prognostic value higher than that of blood pressure alone [48–50], In agreement with the results of the present study, non-dipping hypertension has been associated with autonomic dysregulation [51,52]. Therefore, together these data would support a role for excess leptin in the non-dipping hypertension associated with obesity [53].

A limitation of the present study is the conduction of experiments in male mice only. Based on previous findings from our group demonstrating that leptin induces hypertension via sex-specific mechanisms [54] and involves aldosterone-mediated endothelial dysfunction in females, one could expect that EC LepR deficiency would regulates endothelial function differently in males and females. Therefore, further studies are warranted to define the role of endothelial leptin signaling in the control of endothelial function and blood pressure in females.

5. Conclusion

In summary, using a novel mouse model with a selective deficiency in leptin signaling in endothelial cells, we demonstrated that leptin-mediated increases in NO bioavailability is absent in resistant arteries, specific to conductance blood vessels and does not provide a buffering mechanism against the central pressor effects of leptin. We also provide new evidence that leptin-mediated elevation in blood pressure involves an increase in vascular adrenergic contractility and increase in heart rate caused by a concomitant increase in cardiac sympatho-activation and reduced vagal tone. Thus, strategies that regulate autonomic tone rather than NO bioavailability are promising against obesity and metabolic syndrome-associated hypertension.

Acknowledgments

We thank Dr. David Stepp and James D. Mintz for technical assistance with NMR and metabolic cage studies. The Graphical abstract was created using Servier® medical art https://smart.servier.com/

Funding

This work was supported by the NHLBI (1R01HL130301-01, 1R01HL147639-01A1 and 1R01HL155265-01) and 19EIA34760167 to E.J. Belin de Chantemèle. APS APHYS00010 and 2020AHA000-POST000204982 to R.T.Atawia.

Footnotes

CRediT authorship contribution statement

Reem T. Atawia: Conceptualization, Methodology, Formal analysis, Data curation, Writing – original draft, Funding acquisition. Jessica L. Faulkner: Methodology, Formal analysis, Writing – review & editing. Vinay Mehta: Methodology, Formal analysis, Writing – review & editing. Andrew Austin: Formal analysis. Coleton Jordan: Methodology. Simone Kennard: Methodology. Eric J. Belin de Chanteméle: Conceptualization, Data curation, Supervision, Project administration, Writing – original draft, Funding acquisition.

Declaration of Competing Interest

The authors declare no conflict of interest.

The authors have nothing to disclose.

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