Lipids

, Volume 48, Issue 1, pp 63–73 | Cite as

l-Carnitine and Long-Chain Acylcarnitines are Positively Correlated with Ambulatory Blood Pressure in Humans: The SABPA Study

  • Catharina M. C. Mels
  • Aletta E. Schutte
  • Elardus Erasmus
  • Hugo W. Huisman
  • Rudolph Schutte
  • Carla M. T. Fourie
  • Ruan Kruger
  • Johannes M. Van Rooyen
  • Wayne Smith
  • Nicolaas T. Malan
  • Leoné Malan
Original Article

Abstract

The prevalence of hypertension in sub-Saharan Africa is increasing rapidly, and treatment remains challenging. Although the use of l-carnitine in treatment has received much attention, studies reporting on physiological l-carnitine levels in hypertensives are limited. Our aim was to determine physiological levels of l-carnitine and acylcarnitines in African and Caucasian men, and to investigate associations between ambulatory blood pressure (BP) and carnitine levels. Participants included 101 African and 101 Caucasian teachers. Ambulatory BP measurements were conducted, and l-carnitine and acylcarnitine levels determined. African men showed significantly higher systolic BP (p < 0.001), diastolic BP (p < 0.001) and l-carnitine levels (p = 0.01). In both ethnic groups, partial regression analyses revealed a positive association between BP and l-carnitine, although in Caucasians it was with systolic (r = 0.20, p = 0.045), and in Africans with diastolic BP (r = 0.23, p = 0.023). After adjusting for confounders, an independent positive association between systolic (R 2 = 0.37, β = 0.12, p = 0.041) and diastolic BP (R 2 = 0.39, β = 0.14, p = 0.018) and l-carnitine and long-chain acylcarnitines (R 2 = 0.38, β = 0.17, p = 0.005 and R 2 = 0.39, β = 0.15, p = 0.011) were found, independent of ethnicity. Physiological l-carnitine levels were not only higher in Africans than in Caucasians but also above the expected reference range. Despite promising results on l-carnitine (and its short-chain derivatives) in hypertension treatment regimens, our findings paradoxically show that elevated BP is significantly associated with higher physiological l-carnitine and long-chain acylcarnitine levels.

Keywords

Ambulatory blood pressure l-Carnitine Long-chain acylcarnitines Ethnicity Lipid biochemistry β-Oxidation Fatty acid metabolism Heart lipid metabolism Nuclear receptors 

Abbreviations

ABPM

Ambulatory blood pressure monitoring

ATP

Adenosine-5′-triphosphate

BP

Blood pressure

cIMT

Carotid intima-media thickness

CRP

C-reactive protein

CSWA

Cross-sectional wall area

ESI–MS/MS

Electrospray ionisation tandem mass spectrometry

FRAP

Ferric reducing antioxidant power

GGT

γ-Glutamyl transferase

HDL

High-density lipoprotein

LCFA

Long-chain fatty acids

L-NAME

Nω-nitro-l-arginine methyl ester

MAP

Mean arterial pressure

OCTN2

Organic cation transporter 2

PPARα

Peroxisome proliferator-activated receptor α

ROS

Reactive oxygen species

SABPA study

Sympathetic activity and ambulatory blood pressure in Africans study

Notes

Acknowledgments

The Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) Study would not have been possible without the voluntary collaboration of the participants and the Department of Education, North-West Province, South Africa. We gratefully acknowledge the technical assistance of Mrs. Tina Scholtz, Dr Szabolcs Péter and Sr Chrissie Lessing. This study was supported by the National Research Foundation, South Africa; the North-West University, Potchefstroom, South Africa, and the Metabolic Syndrome Institute, France.

Conflict of interest

The authors declare no conflict of interest. This study was supported by the National Research Foundation, South Africa; the North-West University, Potchefstroom, South Africa; and the Metabolic Syndrome Institute, France.

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Copyright information

© AOCS 2012

Authors and Affiliations

  • Catharina M. C. Mels
    • 1
  • Aletta E. Schutte
    • 1
  • Elardus Erasmus
    • 2
  • Hugo W. Huisman
    • 1
  • Rudolph Schutte
    • 1
  • Carla M. T. Fourie
    • 1
  • Ruan Kruger
    • 1
  • Johannes M. Van Rooyen
    • 1
  • Wayne Smith
    • 1
  • Nicolaas T. Malan
    • 1
  • Leoné Malan
    • 1
  1. 1.Hypertension in Africa Research Team (HART)North-West UniversityPotchefstroomSouth Africa
  2. 2.Centre for Human MetabonomicsNorth-West UniversityPotchefstroomSouth Africa

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