Zhang Haojie, Cui Yuke, Dong Ruihua, Zhang Wen, Chen Shihan, Wan Heng, Chen Chi, Chen Yi, Wang Yuying, Zhu Chunfang, Chen Bo, Wang Ningjian, Lu Yingli
Institute and Department of Endocrinology and Metabolism, Shanghai Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China.
Key Laboratory of Public Health Safety of Ministry of Education, Collaborative Innovation Center of Social Risks Governance in Health, School of Public Health, Fudan University, Shanghai, China.
Endocr Connect. 2021 Apr;10(4):378-386. doi: 10.1530/EC-21-0006.
Bone is thought to be the reservoir of the human lead burden, and vitamin D is associated with bone turnover. We aimed to explore whether exposure to lower 25-hydroxy vitamin D (25(OH)D) levels was associated with higher blood lead levels (BLLs) by increasing the bone turnover rate in individuals with type 2 diabetes.
A total of 4103 type 2 diabetic men and postmenopausal women in Shanghai, China, were enrolled in 2018. Their 25(OH)D, β-C-terminal telopeptide (β-CTX), N-MID osteocalcin and procollagen type 1 N-peptide (P1NP) levels were detected. Their BLLs were determined by atomic absorption spectrometry. Mediation analyses were performed to identify the possible role that bone turnover played in the underlying mechanisms.
In both the men and postmenopausal women, all three bone turnover markers were inversely associated with 25(OH)D and positively associated with the BLL (all P < 0.01) after adjusting for age, current smoking habits, metabolic parameters, duration of diabetes, vitamin D intake, and use of anti-osteoporosis medication. In the mediation analyses, none of the direct associations between 25(OH)D and BLL was significant for the three bone turnover markers, but all three bone turnover markers were found to be significant mediators of the indirect associations between 25(OH)D and BLL.
The association between vitamin D and BLL was fully mediated by bone turnover markers in type 2 diabetic patients (mediation effect). This finding suggested that vitamin D may protect against blood lead exposure from the bone reservoir by decreasing bone turnover in individuals with type 2 diabetes.
骨骼被认为是人体铅负荷的储存库，而维生素D与骨转换有关。我们旨在探讨2型糖尿病患者中，较低的25-羟基维生素D（25(OH)D）水平暴露是否通过增加骨转换率而与较高的血铅水平（BLLs）相关。
2018年，中国上海共有4103名2型糖尿病男性和绝经后女性参与研究。检测他们的25(OH)D、β-羧基端肽（β-CTX）、N-端中段骨钙素和I型前胶原N-端肽（P1NP）水平。通过原子吸收光谱法测定他们的血铅水平。进行中介分析以确定骨转换在潜在机制中可能发挥的作用。
在男性和绝经后女性中，调整年龄、当前吸烟习惯、代谢参数、糖尿病病程、维生素D摄入量和抗骨质疏松药物使用情况后，所有三种骨转换标志物均与25(OH)D呈负相关，与血铅水平呈正相关（所有P<0.01）。在中介分析中，对于三种骨转换标志物，25(OH)D与血铅水平之间的直接关联均不显著，但发现所有三种骨转换标志物均为25(OH)D与血铅水平之间间接关联的显著中介因素。
在2型糖尿病患者中，维生素D与血铅水平之间的关联完全由骨转换标志物介导（中介效应）。这一发现表明，维生素D可能通过降低2型糖尿病患者的骨转换，来保护机体免受骨骼储存库中铅暴露的影响。
