Publication of the week: Professor Paul Trayhurn

Trayhurn, P. & Alomar, S.Y., “Oxygen deprivation and the cellular response to hypoxia in adipocytes – perspectives on white and brown adipose tissues in obesity”, Frontiers in Endocrinology – Genomic Endocrinology 6 (2015), Article 19, 1-8. doi: 10.3389/fendo.2015.00019

Relative hypoxia (lack of oxygen) has been shown to develop in white adipose tissue depots of different types of obese mouse (genetic, dietary), and this leads to substantial changes in white adipocyte (fat cell) function. These changes include increased production of inflammation-related proteins – adipokines (such as IL-6, leptin, Angptl4 and VEGF) – an increase in glucose utilisation and lactate production, and the induction of fibrosis and insulin resistance. Whether hypoxia also occurs in brown adipose tissue depots in obesity has been little considered. However, a recent study has reported low O₂ tension in brown fat of obese mice, this involving mitochondrial loss and dysfunction. We suggest that obesity-linked hypoxia may lead to similar alterations in brown adipocytes as in white fat cells – particularly changes in adipokine production, increased glucose uptake and lactate release, and insulin resistance. This would be expected to compromise thermogenic activity (the ability to produce heat) and the role of brown fat in glucose homeostasis and triglyceride clearance, underpinning the development of the metabolic syndrome. Hypoxia-induced augmentation of lactate production may also stimulate the ‘browning’ of white fat depots through recruitment of UCP1 and the development of the recently discovered ‘brite’ adipocytes.

This ‘Hypothesis and Theory’ article has emanated from the collaborative link that Professor Paul Trayhurn has established with the College of Science at King Saud University in Riyadh, Saudi Arabia, which is funded through their Distinguished Scientist Fellowship programme.

Read the whole article on the NCBI website.

Paul Trayhurn was Dean of Research Strategy and is now a Professorial Fellow in the Clore Laboratory at Buckingham.