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MARGARITA LORENZO Y COLS. ANAL. REAL ACAD. NAC. FARM.

FIGURE 2. The different steps in the development of type 2 diabetes.

Obesity is a risk factor to develop type 2 diabetes, due in part to
the fact that adipose tissue secretes proteins named adipokines that
may influence insulin sensitivity. Adipose tissue, in particular the
visceral compartment, is now recognized as the primary contributor
to the insulin resistance syndrome. Several factors secreted from
adipose tissue, including cytokines, chemokines and FFA, can impair
insulin signaling altering insulin-mediated processes, including
glucose homeostasis and lipid metabolism (9). Accordingly, obesity
is being considered a chronic state of low intensity inflammation.
On the other hand, recent studies reveal that obesity is also
associated with an increase in adipose tissue infiltration of
macrophages, which contribute to the inflammatory process through
the additional secretion of cytokines (10). The mechanisms by which
WAT recruits and maintains macrophages could involve expression
of monocyte chemoattractan proteins and intercellular adhesion
molecule-1, as has been recently described (11). Tumor necrosis
factor (TNF)-a. has been proposed as a link between adiposity and

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