Tehran University Medical Journal

Background: Isosorbide dinitrate has been broadly used in the treatment of various ischemic heart diseases. Isosorbide is a nitric oxide donor which increases blood flow to tumors through vasodilatation and consequently accelerates the access of chemo-drugs to them. Furthermore, this drug has inhibitory effects on angiogenesis, tumor growth and metastasis in vivo. Moreover, its ant-inflammatory effects have also been reported. In the present study we evaluated the effects of isosorbide on the proliferative activity of fibrosarcoma WEHI-164 cell line and peripheral blood mononuclear cells (PBMCs).

Methods: WEHI-164 fibrosarcoma cells and human PBMCs were cultured in complete Roswell Park Memorial Institute (RPMI) 1640 medium with 10% fetal bovine serum and 2×104 cells/mL for WEHI-164 and 2×105 cells/mL for PBMCs. The cells were then incubated at the exponential growth phase with different concentrations of isosorbide (4×10-6-1.6×10-3 M) for 24, 48 and 72 hours. Subsequently, isosorbide effects on proliferation of the cells were evaluated by trypan blue dye exclusion (TB) test and MTT assay. Statistical comparisons between groups were made by analysis of variance.

Results: The proliferative activity of WEHI-164 fibrosarcoma cells and human PBMCs treated with different concentrations of isosorbide, did not show any significant difference with untreated control cells.

Conclusion: The results of this study showed that isosorbide neither had any significant effects on the proliferative activity of fibrosarcoma WEHI-164 cells nor on human PBMCs. Our findings suggest that anti-tumoral effects of isosorbide reported by other investigators may be mediated through non-cytotoxic mechanisms.

Background: Tonsils and adenoid hypertrophy is a major respiratory symptom in children which is partly due to recruitment of inflammatory cells in upper airway lymph nodes as a result of the effects of synthesis and release of different inflammatory cytokines. It seems that infections play role in concert with these cytokines leading to tonsilar hypertrophy and other pathologic consequences. It is proposed that cellular infiltrate of tonsils and adenoids may secrete different quantities of these cytokines compared with peripheral blood mononuclear cells (PBMC) cultures.
Methods: Among patients who were admitted for adenotonsillectomy to the ENT ward, 37 patients, under 1-12 years old patients with fulfill criteria selected to include the study. Excised adenoid and tonsils cultured and inflammatory cytokines Interferon-γ (INF-γ), Interlukine-1 (IL-1), IL-6, IL-8 and tumor necrosis factor-α (TNF-α) measured in cellular culture supernatant. The same cytokines measured in PBMC cultures.
Results: The data shows that there is a significant difference between IFN-γ and IL-8 amounts in adenoid tissue culture supernatant and PBMC culture of our patients. Furth-ermore, the amounts of IFN-γ, IL-1 and IL-8 showed considerable difference between tonsilar tissue culture supernatant and PBMC culture of these patients. Although there is a significant correlation between IL-6 amounts in tissue culture supernatant and PBMC culture (P=0.02), the respective data for TNF is only almost significant.
Conclusion: Inflammatory cytokines may have significant role in the early provoke of inflammation occurred in hypertrophied tonsils and adenoid. The majority of these cyt-okines increase the expression of adhesion molecules on epithelial cells and influence the recruitment of leucocytes and inflamed tonsils. On the other hand lack of sufficient cytokine release may lead to persistent infections and may cause chronic inflammation and hypertrophied tissue.