Liver enzymes mediate association of particulate matter exposure with diabetes risk

Liver enzymes play a partial role in the relationship between exposure to particulate matter (PM) and risk of diabetes, indicating the involvement of lipid accumulation, oxidative stress, and chronic inflammation in the liver in its pathogenesis, reports a recent study.

“Although liver-derived biological intermediates may play irreplaceable roles in the pathophysiology of diabetes, few studies have explored this in the association between PM and diabetes,” the researchers said.

This study included a total of 7,963 participants from the China Multi-Ethnic Cohort. A group of researchers assessed residential exposure to PM using a validated spatial-temporal assessment method. The criteria from the American Diabetes Association were used to diagnose diabetes.

Multivariable regression models were used to explore the associations between PM, liver enzyme (alanine aminotransferase [ALT], aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transpeptidase [GGT]), and diabetes. Finally, mediation analysis was conducted to determine the role of liver enzymes in the relationship between PM and diabetes.

PM exposure showed a positive association with diabetes onset (odds ratio [OR] for every 10-μg/m³ increment in ≤1 μm PM [PM₁], 1.32, 95 percent confidence interval [CI], 0.83‒2.09; OR in ≤2.5 μm (PM_2.5), 1.33, 95 percent CI, 1.07‒1.65; OR in ≤10 μm (PM₁₀), 1.18, 95 percent CI, 1.02‒1.36).

Of note, ALT (4.47 percent) and GGT (4.78 percent) appeared to significantly facilitate the association between PM_2.5 and diabetes, while ALT (4.30 percent) showed a mediating role on PM₁₀. None of these liver enzymes, however, exhibited a significant mediating effect on PM₁.