CD14 and tuberculosis: Secondly, metformin treatment reduced soluble CD14, CD163, and inflammatory C-reactive protein levels in TB patients with diabetes, significantly decreased MMP-1, −2, −3, −7, −9, and − 12 levels, and promoted smear conversion, indicating that metformin has significant anti-inflammatory and lung injury improvement effects, and greatly reduced mortality (Degner et al., 2018; Kumar et al., 2018; Kumar N. P. et al., 2019; Li et al., 2021; Wang Y. et al., 2022).