Cytoprotective effects of creosote bush () and Southern live oak () extracts against toxicity induced by venom of the black-tailed rattlesnake ().

The venom of (v) poses a threat to human health, as it contains a mixture of toxins that can cause cytotoxic, necrotic, and hemolytic effects. The present study assessed methanolic and acetone extracts from leaves and flowers of , as well as the bark of as potential suppressors of the toxic effects of v. The content of total phenols, flavonoids, and tannins of the plant extracts were quantified for the suppression of v cytotoxicity in two cell culture models, human lymphocytes and porcine aortic endothelial (PAE) cells. Extracts from displayed a greater concentration of total phenols, flavonoids, and tannins. Co-incubation of lymphocytes and PAE cells with fixed concentrations of v and plant extracts resulted in decreased v-induced cytotoxicity. A 24-hour co-incubation of lymphocytes with v (2.36 ± 0.17 µg/mL) and 0.5 µg/mL of methanolic leaf extract from (LLM) significantly suppressed the venom-induced cytotoxicity by 37.33 ± 8.33%. Similarly, the LLM extract (4 µg/mL) caused a significant decrease in v cytotoxicity after 24 hours in PAE cells. In contrast, while the acetone extract of bark (QA) suppressed cytotoxicity by 29.20 ± 3.51% ( < 0.001) in lymphocytes, it failed to protect PAE cells against v after 24 hours. In PAE cells, a shorter 4-hour co-incubation showed significant suppression of cytotoxicity with both extracts. Our results collectively suggest that LLM and QA possess cytoprotective properties against the toxic effects of v, and thus establish extracts from these plants as potential therapeutic interventions against envenomation.