243PST-297S than PST 287 K, and this one, in turn, higher than WT-PST. These
differences in secondary structure, have a direct relation with the plasma glucose
and gluconeogenic genes expression, being highest in case of PST-297S. These
findings could shed light on the inter-individual variations in glucose homeostasis,
which opens new doors to a better diagnostics and personalized therapies of glu-
cose/insulin disorders (Allu et al. 2014 ).
8 Final Remarks
The isolation of the PST peptide from porcine pancreas 30 years ago, reporting a
biological effect, started up the era of the extracellular function of CGA as a precur-
sor of peptides with regulatory functions. Different autocrine, paracrine and endo-
crine effects of PST have been described, and we have proposed that metabolic
effects of PST could be useful in the physiology of stress, and could also participate
in pathophysiological conditions such as insulin resistance. Different mechanisms
of PST action have been proposed so far, and new mechanisms may be revealed in
the future. Nevertheless, the precise role of PST in the context of CGA function in
health and disease deserves further investigation, and we are positive that it will
help to find the role of CGA as a precursor of biologically active peptides.
Acknowledgement We acknowledge the financial support of the Consejería de Innovacion,
Ciencia y Empresa, Junta de Andalucía, Spain (Proyecto de Excelencia 08-CTS-4329), funded in
part by FEDER.
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