Thermoneutrality modifies the impact of hypoxia on lipid metabolism

Jonathan Jun, Mi-Kyung Shin, Qiaoling Yao, Ronald Devera, Shannon Fonti-Bevans, Vsevolod Polotsky

Research output: Contribution to journalArticle

Abstract

Hypoxia has been shown to rapidly increase triglycerides in mice by decreasing plasma lipoprotein clearance. However, the usual temperature of hypoxic exposure is below thermoneutrality for mice, which may increase thermogenesis and energy requirements, resulting in higher tissue lipid uptake. We hypothesize that decreased lipid clearance and ensuing hyperlipidemia are caused by hypoxic suppression of metabolism at cold temperatures and, therefore, would not occur at thermoneutrality. Twelve-week-old, male C57BL6/J mice were exposed to 6 h of 10% O2 at the usual temperature (22°C) or thermoneutrality (30°C). Acclimation to 22°C increased lipid uptake in the heart, lungs, and brown adipose tissue, resulting in lower plasma triglyceride and cholesterol levels. At this temperature, hypoxia attenuated lipid uptake in most tissues, thereby raising plasma triglycerides and LDL cholesterol. Thermoneutrality decreased tissue lipid uptake, and hypoxia did not cause a further reduction in lipid uptake in any organs. Consequently, hypoxia at thermoneutrality did not affect plasma triglyceride levels. Unexpectedly, plasma HDL cholesterol increased. The effect of hypoxia on white adipose tissue lipolysis was also modified by temperature. Independent of temperature, hypoxia increased heart rate and glucose and decreased activity, body temperature, and glucose sensitivity. Our study underscores the importance of ambient temperature for hypoxia research, especially in studies of lipid metabolism.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Endocrinology and Metabolism
Volume304
Issue number4
DOIs
StatePublished - Feb 15 2013

Fingerprint

Lipid Metabolism
Lipids
Temperature
Triglycerides
Glucose
White Adipose Tissue
Brown Adipose Tissue
Thermogenesis
Lipolysis
Acclimatization
Hypoxia
Hyperlipidemias
Body Temperature
LDL Cholesterol
HDL Cholesterol
Lipoproteins
Heart Rate
Cholesterol
Lung
Research

Keywords

  • Altitude
  • Hypoxia
  • Lipids
  • Metabolism
  • Thermoregulation

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)
  • Endocrinology, Diabetes and Metabolism

Cite this

Thermoneutrality modifies the impact of hypoxia on lipid metabolism. / Jun, Jonathan; Shin, Mi-Kyung; Yao, Qiaoling; Devera, Ronald; Fonti-Bevans, Shannon; Polotsky, Vsevolod.

In: American Journal of Physiology - Endocrinology and Metabolism, Vol. 304, No. 4, 15.02.2013.

Research output: Contribution to journalArticle

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