Vol. 5, n. 1, January-March 2009 1th International ... - Salute per tutti

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C. Ferreri
the double layer proteins, ionic channels,
receptors are positioned. The membrane fatty
acid composition and the balance between saturated
and unsaturated structures are essential
to ensure the physiological status of the organization
and its functioning. Moreover this balance
can affect skin status and functionality.
Several factors influence the presence of saturated
fatty acids (SFA), monounsaturated fatty
acids (MUFA) and polyunsaturated fatty acids
(PUFA), and in particular:
a) the dietary regime adopted by the subject,
especially considering that the PUFA omega-
6 and omega-3 precursors (linoleic and alfalinolenic
acids, see Figure 2) are “essential”,
which means that they are only obtained
f rom nutrition, and afterw a rds they are
transformed (by desaturase and elongase
enzymes) into the other components of the
two families;
b) the oxidative and free radical events, which
occur under several metabolic conditions,
either physiological and pathological ones,
and can induce MUFA and PUFA transformations
1 .
It is worth underlining that the oxidative and
free radical events are part of natural mechanisms
of defense, as well as cell signaling, therefore
they are physiological and have not to be
totally suppressed. Under pathological situations
or exposition to specific agents (radiations,
smoke, UV light) an uncontro l l e d
Journal of Plastic Dermatology 2009; 5, 1
increase of these events can occur, which brings
to transformations and loss of normal levels, as
well as to the formation of toxic metabolites.
The body has a control of the oxidative and free
radical status, through enzymatic and molecular
systems, which intervene to protect the natural
components and neutralize toxicity.
However, when degradation factors increase
indiscriminately, the endogenous systems do
not succeed to control all damages and keep
them within the “good” limits.
As in other cell structures, the membrane faces
several metabolic conditions which can influence
the lipid composition and change its characteristics.
Nowadays all these changes can be
followed-up and interpreted also through the
approach of lipidomics. Some years ago the
multidisciplinary field of lipid research has
been profoundly innovated thanks to the birth
of lipidomics 2-4 . This discipline has introduced
a new dynamic interpretation of the lipid structures
existing in living organisms, evidencing
the importance of monitoring their transformations,
either quantitatively and qualitatively,
connected to the metabolic and biochemical
changes occurring in cells, through the comparison
between physiological and pathological
situations.
Also in cell aging, transformations are followedup
in function of time and can be understood
by the lipidomic approach. Lipids have to be
considered not only as single structures but also
Figure 2.
Enzymatic competition between the omega-6 (left) and omega-3 (right) families of essential fatty acids.