# Crack Cocaine Smoke Induces Tissue Degeneration in Rat Submandibular Glands by Toll-like Signaling Pathway

## TL;DR

Crack cocaine smoke causes damage to rat salivary glands, increasing cell aging and growth.

## Contribution

This study reveals how crack cocaine smoke harms salivary glands via toll-like signaling in rats.

## Key findings

- Crack cocaine smoke caused histopathological changes in all exposed rat groups.
- Exposure increased BCL-2, P16, and Ki-67 expression, indicating cell senescence and proliferation.
- MYD88 expression was significantly higher only in the highest dose group.

## Abstract

Background: This study investigated the impact of crack cocaine smoke exposure on the submandibular salivary gland of Wistar rats. Methods: The animals were distributed into four groups: control (CTRL); 25 mg exposure (CK25); 50 mg exposure (CK50); and 100 mg exposure (CK100). The animals were exposed to crack cocaine smoke once a day for five consecutive days. Results: Exposure to crack cocaine smoke-induced histopathological changes in submandibular salivary glands in all groups under exposure. The immunohistochemical analysis demonstrates that exposure to crack cocaine smoke led to an increase in BCL-2 and P16 expression in all groups exposed to crack cocaine (p < 0.05). The analysis of Ki-67 expression revealed a significant increase in immunoreactive cells across all exposure groups (p < 0.05). Although MYD88 expression was observed in all crack cocaine-exposed groups, only the group treated with the highest dose (100 mg) exhibited a statistically significant increase compared to the control group (p < 0.05). Conclusions: In summary, this study demonstrates that exposure to crack cocaine smoke-induced tissue degeneration in the submandibular salivary gland, increasing cellular senescence and promoting compensatory cell proliferation in Wistar rats.