RESUMEN
Introduction: In the U.S., xylazine, the veterinary non-opioid sedative, has emerged as a major threat to people who use illicitly manufactured fentanyl and other drugs. The aim of this study was to compare wastewater detection of xylazine with other public health and safety surveillance data from 2019 to 2023 in Kentucky. Methods: Wastewater samples from 5 rest areas, 2 truck weigh stations, and 4 wastewater treatment plants were tested for xylazine. Wastewater xylazine positivity rates were compared with xylazine-positive submission rates from the National Forensic Laboratory Information System and Kentucky's fatal overdoses in 6-month periods (Period 1=January-June; Period 2=July-December). Results: Xylazine was detected in 61.6% (424 of 688) of daily wastewater samples from roadway sites/wastewater treatment plants. For roadways, detection increased from 55% (Period 1, 2021) to 94% (Period 1, 2023), and wastewater treatment plants had an overall detection of 25.8% (n=66 samples, Periods 1 and 2, 2022). Increasing roadway positivity corresponded to trends in National Forensic Laboratory Information System xylazine-positive submission rates: from 0.19 per 1,000 submissions (Period 1, 2019) to 2.9 per 1,000 (Period 2, 2022, latest available). No deaths from xylazine were reported publicly in Kentucky, although this study's authors identified 1-4 deaths (true count suppressed) in the overdose surveillance system, which, in back-of-the-envelope comparisons with other states, is far fewer than expected. Conclusions: Wastewater signals indicate broad geographic exposure to xylazine in Kentucky, yet health outcomes data suggest otherwise. These findings may inform regional, national, and international efforts to incorporate wastewater-based drug surveillance. Harm-reduction activities along roadways and other suitable locations may be needed.
RESUMEN
Chronically elevated levels of glucose are deleterious to pancreatic ß cells and contribute to ß cell dysfunction, which is characterized by decreased insulin production and a loss of ß cell identity. The Krüppel-like transcription factor, Glis3 has previously been shown to positively regulate insulin transcription and mutations within the Glis3 locus have been associated with the development of several pathologies including type 2 diabetes mellitus. In this report, we show that Glis3 is significantly downregulated at the transcriptional level in INS1 832/13 cells within hours of being subjected to high glucose concentrations and that diminished expression of Glis3 is at least partly attributable to increased oxidative stress. CRISPR/Cas9-mediated knockdown of Glis3 indicated that the transcription factor was required to maintain normal levels of both insulin and MafA expression and reduced Glis3 expression was concomitant with an upregulation of ß cell disallowed genes. We provide evidence that Glis3 acts similarly to a pioneer factor at the insulin promoter where it permissively remodels the chromatin to allow access to a transcriptional regulatory complex including Pdx1 and MafA. Finally, evidence is presented that Glis3 can positively regulate MafA transcription through its pancreas-specific promoter and that MafA reciprocally regulates Glis3 expression. Collectively, these results suggest that decreased Glis3 expression in ß cells exposed to chronic hyperglycemia may contribute significantly to reduced insulin transcription and a loss of ß cell identity.