Fig. 1
Establishment of DIO and T1D mouse models for real-ambient PM exposure. A schematic diagram of experimental design: six-week-old male C57BL/6 mice were injected with 50 mg/kg of streptozotocin (STZ) for 5 consecutive days or fed a 45% high-fat diet to generate DIO and T1D mice, followed by a 4-week real-ambient PM exposure (n = 20). B. The mean concentration of daily PM2.5 in ambient air (black line), PM exposure chambers (red line), and AF control chambers (blue line) during the exposure period, with reference to 35 µg/m3 of China’s Air Quality Standards and 150 µg/m3 of the threshold for heavy PM2.5 pollution in China. Eight representative indices of metabolic disorders that were divided into 4 categories: (1) body composition: body weight gain (C) and fat percentage (D); (2) daily water intake (E) (n = 10); (3) dysregulation of glucose metabolism: fasting glucose (F) and insulin levels (G) (n = 5); and (4) dysregulation of lipid metabolism: triglyceride (H), cholesterol (I), and low-density lipoprotein cholesterol or LDL-C (J) (n = 3). The data are presented as mean ± SEM. *P < 0.05 (PM vs. AF); #P < 0.05 (DIO vs. ND); &P < 0.05 (T1D vs. ND); $P < 0.05 (T1D vs. DIO).