Garlic (Allium sativum) modifies TNF-α mRNA production in macrophages challenged with LPS and Candida albicans
Garlic (Allium sativum) has a long recorded history as a medicinal agent. Modern efforts have begun to elucidate the effects of garlic on the immune system. Macrophages are essential innate immune cells that-when activated-produce protein signals called cytokines. Lipopolysaccharide (LPS) is an outer membrane component of gram-negative bacteria. Candida albicans (C. albicans) is an opportunistic yeast species that heavily infects immunocompromised individuals. We previously reported that garlic increases the secretion of a cytokine, TNF-α, from LPS activated J774A.1 (J7) macrophages. We have found similar results in LPS activated mouse-harvested macrophages but did not see an effect in LPS activated RAW 264.7 (RAW) macrophages. We further observed that garlic reduces TNF-α secretion from C. albicans activated J7, RAW, and mouse-harvested macrophages. The mechanism of action utilized by garlic to exert its effects on immunity remains elusive. Thus, we sought to understand if garlic alters TNF-α mRNA levels from LPS or C. albicans activated macrophages. To this end, we plated J7 and RAW macrophages at a concentration of 1.25x105 cells/mL and mouse-harvested macrophages at a concentration of 1.00x106 cells/mL. Macrophages were then challenged with LPS (0.1 ng/mL) or heat-killed C. albicans (6.25x106) cells/mL and treated with a 1:500 dilution of garlic. Following a 2 hour incubation, mRNA was extracted and analyzed via RT-qPCR. Preliminary data shows that garlic reduces TNF-α mRNA levels in LPS activated J7, RAW, and mouse-harvested macrophages. Results also suggest that garlic reduces TNF-α mRNA levels in C. albicans activated J7, RAW, and female mouse-harvested macrophages.