Peptidases from Latex of Carica candamarcensis Upregulate COX-2 and IL-1 mRNA Transcripts against Salmonella enterica ser. Typhimurium-Mediated Inflammation

Abstract EN

The immunomodulatory properties of a mixture of cysteine peptidases (P1G10) obtained from the fruit lattice of Carica candamarcensis were investigated.

P1G10 was obtained from fresh latex samples by chromatography in a Sephadex column and initially administered to Swiss mice ( n = 5 ; 1 or 10 mg/kg) via i.p.

After 30 min, the mice were injected with carrageenan (0.5 mg/mouse) or heat-killed S.

Typhimurium (107 CFU/mL; 100°C/30 min) into the peritoneal cavity.

Afterwards, two animal groups were i.p.

administered with P1G10 ( n = 6 ; 1, 5, or 10 mg/Kg) or PBS 24 hours prior to challenge with live S.

Typhimurium (107 CFU/mL).

P1G10 stimulated the proliferation of circulating neutrophils and lymphocytes, 6 h after injection of carrageenan or heat-killed bacteria, respectively.

Furthermore, survival after infection was dose-dependent and reached 60% of the animal group.

On the other hand, control mice died 1–3 days after infection.

The examination of mRNA transcripts in liver cells 24 h after infection confirmed fold variation increases of 5.8 and 4.8 times on average for IL-1 and COX-2, respectively, in P1G10 pretreated mice but not for TNF-α, IL-10, γ-IFN and iNOS, for which the results were comparable to untreated animals.

These data are discussed in light of previous reports.