Garlic Volatile Oil and T-2 Toxin Effects

Effects of elephant garlic (Allium ampeloprasum) volatile oil (GVO) and trichothecene (T2) toxin were studied in Swiss albino mice. The animals were 1) topically applied GVO, 2) topically applied T-2 toxin, 3) topically applied GVO followed by T-2 toxin (GVO/T-2), and 4) T-2 toxin application followed by GVO (T-2/GVO) on the right footpad. All animals were observed by Langerhans cell enumeration and pathological changes of the footpad on days 1, 3, 5 and 7. The number of Langerhans cells in the GVO treated group (1,097±33/mm to 1,624±19/mm) was not significantly different when compared with the corresponding control left footpad (1,143±33/mm to 1,674±21/ mm). Langerhans cells density in T-2 toxin treated group (629±29/mm to 1,090±31/mm) was reduced by 20-35% of the opposite control footpad (962±40/mm to 1,392±29/mm). Furthermore, GVO/ T-2 and T-2/GVO treated mice showed a decrease in Langerhans cell number than a single T-2 toxin treated group. While Langerhans cells in T-2 toxin, GVO/T-2 and T-2/GVO groups revealed a smaller cell size with shortening dendritic processes when compare to the normal control group. Histopathological findings of the footpad skin in T-2 toxin treated group revealed epidermal desquamation and necrosis with edema and inflammatory cells infiltration. While GVO/T-2 and T-2/GVO showed a similar sequence but a lesser severe degree. These findings suggested that GVO both in pre-and posttreatment could protect T-2 toxin induced epidermal damage in a mouse footpad. The elephant garlic (Allium ampeloprasum Linn.) or ‘Kratiam-tone’ in Thai is believed to have anti-hepatotoxic activities and its steroidal saponin antifungal activities (Morita et al, 1988). At the present time, garlic in various preparations is regarded by the US Food and Drug Administration (FDA) as a natural and common food substance in the US food supply. Currently, there are no data regarding possible garlic toxicity from the National Toxicology Program, the US Government Office that is responsible for federal evaluation of chronic toxicity of chemicals (Dausch and Nixon, 1990). Trichothecene (T-2) toxin is one of the most toxic of the 12,13-epoxytrichothecene mycotoxins produced by the Fusarium species. T-2 toxin has been implicated in alimentary toxic aleukia (ATA) in Russia, a disease which has killed thousands of people (Ueno, 1977). It is a potent inhibitor of protein and DNA synthesis (Rosenstein and Lafarge-Frayssinet, 1983) and suppressed SOUTHEAST ASIAN J TROP MED PUBLIC HEALTH 900 Vol 34 No. 4 December 2003 antibody synthesis against sheep red blood cells (SRBC) observed by a delayed footpad swelling response in the classic delayed type hypersensitivity reaction (Masuko et al, 1977). The mechanism of action of T-2 toxin in inhibiting protein synthesis may be result from defective epidermal antigen presentation. Langerhans cells play a critical role in cutaneous immunological reactions (Weiss, 1988). The epidermal Langerhans cell is a potent antigen-presenting cell for eliciting the success of intradermal immunization and carries out the immunological activity in vivo and in vitro. (Taweechaisupapong et al, 1996). The mobilization of the Langerhans cell to the draining lymph node is important to initiate the immune response to an epidermally acquired virus infection (Johnston et al, 2000). Langerhans cells are also the targets of dengue virus infection (Marovich et al, 2001). It implicated for impaired skin immunologic functions in animals or humans exposed epidermally to T-2 toxin. The present study deals with the effect of elephant garlic volatile oil (GVO) and T-2 toxin on mice foot pad skin, which is richy supplied with epidermal Langerhans cells. Topical application of GVO after T-2 toxin should have to beneficial effects on mice footpads both in the dermatological and epidermal Langerhans cell populations. MATERIALS AND METHODS