Safety assessment and exploration of the mechanism of toxic effects of diallyl trisulfide: Based on acute and subacute toxicity and proteomics experiments.

ETHNOPHARMACOLOGICAL RELEVANCE: Garlic (Allium sativum L.) is a widely consumed spice and condiment around the world, applied both as a food and as a traditional medicine, and is a natural strengthening agent for the body's circulatory and nervous systems. Diallyl trisulfide (DATS) is the major volatile organosulfur phytochemical found in garlic, with antithrombotic, anticoagulant, and antiplatelet activities as well as antioxidant, anti-infective, and other pharmacological effects. However, the safe dose and the underlying mechanisms of its toxic effects remain elusive.

AIM OF THE STUDY: DATS, an important pharmacologically active compound found in garlic, has garnered attention for its ability to fight cancer, antioxidant, anti-infective, and cardioprotective. The aim of this study was to evaluate the safety of DATS and to elucidate the potential mechanisms of its toxicity.

MATERIALS AND METHODS: In this study, ICR mice were selected for acute and subacute toxicity experiments according to OECD guidelines. The toxicity profile of DATS was analyzed by computer prediction software. Also, key differential proteins in spleen and serum were analyzed by proteomics. The binding stability of DAST to differential proteins was analyzed by molecular docking. Additionally, the regulatory relationship between DATS and differential proteins was verified by Western blot and ELISA experiments.

RESULTS: The results showed that the LD50 value of DATS in acute toxicity was 188.67 mg/kg. In subacute toxicity, water consumption and food intake were reduced in both male and female mice. In addition, the spleen and small intestinal organ coefficients were significantly elevated in male mice at the high dose of DATS; the blood biochemical indices ALB and TP were also significantly elevated. HE staining results showed significant damage to the spleen, liver, small intestine, and kidney of mice at high doses of DATS. Spleen and serum proteomics analyses showed that DATS significantly inhibited ZBP1 expression and upregulated TEC. ADMETlab 2.0 software predictions identified DATS as having potential genotoxicity, dermal sensitization, carcinogenicity, and respiratory and ocular toxicity. Docking results showed that the binding energies between DATS and TEC protein (PDB: 6F3F) and ZBP1 protein (PDB: 4KA4) were -3.7 kcal/mol, -2.4 kcal/mol, respectively. Western blot results showed that DATS-H significantly inhibited the expression of ZBP1 (only in male mice) and Bcl-2 proteins. ELISA results showed that DATS-H significantly increased the level of TEC protein both in male and female mice.

CONCLUSIONS: Long-term administration of high-dose DATS may carry some risk of toxicity. Based on the amount of DATS in garlic, it is recommended that adults should not take more than 359 mg of DATS and 84.5 g of garlic per day. The mechanism of toxicity may be related to the fact that DATS significantly inhibits ZBP1 expression, upregulates TEC, and promotes apoptosis. This study provides valuable toxicological data for the effective evaluation of the long-term toxicity of DATS and offers an additional experimental basis for developing DATS as a healthy food or drug.