INVESTIGADORES
MOZZI Fernanda Beatriz
congresos y reuniones científicas
Título:
Gastroprotector effect of the exopolysaccharide produced by Streptococcus thermophilus CRL 1190 on chronic gastritis
Autor/es:
RODRÍGUEZ C.; MEDICI M.; MOZZI F. ; FONT DE VALDEZ, G.
Lugar:
San Miguel de Tucumán
Reunión:
Simposio; III Simposio Internacional de Bacterias Lácticas. II Encuentro RED BAL Argentina; 2009
Resumen:
Gastritis is a common disorder where discontinuity in
the gastric mucosa is observed. It is caused by several factors such as
intensive use of anti-inflammatory drugs (e.g. acetyl-salicylic acid; ASA) producing
toxic effects on the gastric epitelial cells with amplification of the
inflammatory process by expression of pro-inflammatory cytokines.
Streptococcus thermophilus is used as starter culture for the manufacture of
fermented products such as yogurt and cheese. Certain S. thermophilus strains
are able to produce exopolysaccharides (EPS); these compounds play an important
role in the dairy industry by improving the texture and rheology of fermented
foods. In addition, EPS
have been claimed to display immunostimulatory and anti-ulcer effects in the
host. Previously, we demostrated that BALB/c mice fed with
a fermented milk with the EPS-producing S. thermophilus CRL 1190 (FM
1190) was efficient in gastritis preventive and therapeutic treatments. The aim of this work was to evaluate whether the
EPS produced by S. thermophilus CRL
1190 (EPS1190) was responsible for the antigastritis effect observed. Thus, the
EPS 1190 was isolated from 16-h old milk cultures grown at 37°C by using a deproteinization/precipitation
technique with trichloroacetic acid and ethanol and purified by dyalisis. BALB/c
mice were fed with 4 mg/Kg/d of the EPS suspended in milk (M-EPS 1190) and
water (W-EPS 1190) for 7 days before and after gastritis induction with ASA
(400 mg/Kg/d during 10 days). The minimal dose of EPS with gastroprotector
effect was also determined. The inflammatory level was assayed by histopathology
of the gastric mucosa (hematoxylin-eosin), and the number of pro-inflammatory
(INFg+ and TNFa+) and regulatory (IL-10+)
cytokine-producing cells by indirect immunofluorescence. The mucus gel layer thickness and the volume of
intramucosal mucus layer were also determined. M-EPS 1190, but not W-EPS 1190,
was able to modulate gastritis, displaying similar histological, histochemical
and immunological parameters to those of healthy animals and those treated with
the FM 1190. No positive effect was obtained at EPS concentrations lower than 4
mg/kg/d. These results indicate that even though the EPS
is responsible for the beneficial effect, the interactions between EPS and milk
proteins seem to play an important role in the gastroprotection observed.