Comparative analysis of in vitro immunomodulatory potential of four Gentiana species

Among Gentiana species present in the Balkan Peninsula, eight are used in traditional medicine mainly for the treatment of gastrointestinal disorders, but other applications have also been recorded, including improving the immune system and health maintenance.

To examine the immunomodulatory potential of methanol extracts obtained from the aerial parts of Gentiana asclepiadea, G. utriculosa, G. cruciata, and G. dinarica.

Following phytochemical analysis of Gentiana extracts by HPLC, splenocytes isolated from Wistar rats were stimulated with the extracts in culture for 48 h, and changes in cell viability and function (nitric oxide (NO), myeloperoxidase (MPO), and cytokine production) were examined.

Among the examined extracts, G. asclepiadea was the most toxic to immune cells (IC₂₀ = 146 μg/ml), followed by G. dinarica (IC₂₀ = 331 μg/ml), G. utriculosa (IC₂₀ = 467 μg/ml), and G. cruciata (IC₂₀ = 705 μg/ml). G. asclepiadea and G. cruciata extracts both suppressed (2 μg/ml) and stimulated (10 and 50 μg/ml) interferon-γ (IFN-γ) production, while G. cruciata extract additionally suppressed interleukin (IL)-10 but stimulated the IL-17 response. Extracts obtained from G. utriculosa and G. dinarica suppressed MPO (all examined doses), IL-6 (10 and 50 μg/ml), IL-17 (2 μg/ml), and IFN-γ (50 μg/ml).

All examined Gentiana species extracts have the potential to modulate immune system function, which may be beneficial in the treatment of various diseases.