aqueous extract reduces T cell response and ameliorates type I diabetes in NOD mice.

Background: New products with tolerogenic properties on T cell response are necessary to improve current efficacy, cost and side effects of immunosuppressants. aqueous extract (PsAE) have reported cytotoxic, antitumoral, antiatherogenic and antileishmanial activities, containing phytochemicals with immune-related activities. Despite these, there are no previous studies with respect to PsAE suppressive properties over T cell proliferation and their function.

Goal: Because of previous antecedents, this study aims to evaluate the effect of PsAE on T cell activation, proliferation, cytokine production, and to investigate its effect over an model of type 1 diabetes (T1D).

Experimental Procedure: Splenocytes and sorted CD4/CD8 from wild type C57BL/6 mice were cultured to determine activation, IFN-γ release and T-cell proliferation after polyclonal stimulation. NOD (non-obese diabetic) mice were used to study the effects of orally administered extract on glycemia, insulitis stages and perforin-1 (PRF-1)/granzyme-B (GRZ-B) expression.

Results: In primary cultures, the plant extract impairs T cell activation, decreases IFN-γ release, and reduces proliferation after different polyclonal stimuli. , PsAE improves NOD mice glycemic levels and T1D progression by diminution of pancreas insulitis and reduction of PRF-1 and GRZ-B mRNA expression. To our knowledge, this is the first report characterizing the therapeutic properties of PsAE on T cell activation.

Conclusion: The current work provides evidence about and immunosuppressive effects of PsAE and promotes this plant extract as a complementary and alternative treatment in autoimmune T-cell mediated diseases as T1D.