Summary:
Pfeiffer and colleagues years ago pointed out that different distributions and amounts
of adipose tissue are associated with abnormalities of lipolysis and lipoprotein metabolism.
Adipose tissue has several crucial roles including (i) mobilization from stores of
fatty acids as an energy source, (ii) catabolism of lipoproteins such as very-low-density
lipoprotein and (iii) synthesis and release of hormonal signals such as leptin and
interleukin-6. These adipose tissue actions are crucially regulated by nutrition.
The review considers the existence of metabolic pathways and modes of regulation within
adipose tissue, and how such metabolic activity can be quantitated in humans. Nutrition
can influence adipose tissue at several ‘levels’. Firstly the level of obesity or
malnutrition has important effects on many aspects of adipose tissue metabolism. Secondly
short-term overfeeding, underfeeding and exercise have major impacts on adipose tissue
behaviour. Lastly, specific nutrients are capable of regulating adipose tissue metabolism.
Recently there have been considerable advances in understanding adipose tissue metabolism
and in particular its regulation. This review discusses the behaviour of adipose tissue
under various nutritional conditions. There is then a review of recent work examining
the ways in which nutritional influences act via intra-cellular mechanisms, insulin
and the sympathetic innervation of adipose tissue.
Key words:
Insulin - non-esterified fatty acids - obesity - catecholamines - leptin
