TNNI3 and myocardial infarction: Regarding serum omentin-1 level, it decreased from 27.13 ± 1.55 pg/mL in healthy controls to 23.71 ± 1.161 pg/mL in patients with MI not previously treated with metformin, while serum cardiac troponin-I increased from 21.202 ± 0.636 pg/mL in healthy controls to 79.53 ± 3.60 pg/mL in patients with MI not previously treated with metformin (Table 3).