Relationship between the expression of TNFR1-RIP1/RIP3 in peripheral blood and cognitive function in occupational Al-exposed workers: A mediation effect study

Abstract

Aluminium (Al), not essential for biological activities, accumulates in the tissues. It exerts toxic effects on the nervous system, inducing in humans’ irreversible cognitive impairment. In this study, a cluster sampling method was used to observe the cognitive function of long-term occupational Al-exposed workers in a large Al factory, and determine the expression of peripheral blood tumour necrosis factor receptor 1 (TNFR1), receptor-interacting protein 1 (RIP1), and RIP3. TNF-alpha, expressed in blood macrophages and microglia, with its receptors TNFR1, TR1 and TR3, enhances the necroptosis of neurons. Additionally, the relationship between the expression of TNFR1, RIP1, and RIP3 in the peripheral blood of long-term occupational Al-exposed workers and changes in their cognitive function was explored. The differences in the distributions of clock drawing test (CDT) scores among the three groups were statistically significant (P < 0.05). The results of correlation analysis showed that RIP1 and RIP3 protein contents were negatively correlated with mini-mental state examination (MMSE) and CDT scores (P < 0.05). Plasma Al content was positively correlated with other biological indicators (P < 0.05), and negatively correlated with MMSE and CDT scores (P < 0.05). Results showed that RIP3 protein had an incomplete mediation effect between plasma Al content and cognitive function. This suggests that Al may affect cognitive function by influencing the expression of TNFR1, RIP1, and RIP3 in the nervous system.