The Effect of Tannic Acid and Tannic Extract on Rat Adipocyte Metabolic Components

Tannins are polyphenolic compounds naturally produced in plants. There are two major classifications of tannins, hydrolyzable (H) and condensed (C), which have been studied for potential therapeutic uses. Tannins were reported to suppress differentiation of pre-adipocytes into mature, lipid-filled adipocytes, which was associated with the inhibition of lipid droplet formation.  The adipogenic hormone, leptin, is associated with adipocyte lipid droplet metabolism. Therefore, it is hypothesized that tannins, H and C, will influence lipid metabolic components, such as leptin, in mature adipocytes.  Subcue fat was collected from rats (n=5) for cell culture.  Approximately 3×106cells were cultured with/without gall nut-tannic acid (H) or Quebracho plant-tannins (C) (1mg, 100ug, 10ug, 1ug, or 0ug) and incubated at 37°C in an atmosphere of 5% CO2 and 95% air for 2 and 18h. Leptin gene expression increased (P<0.05) in cells treated for 18h.  Free glycerol was dose dependently suppressed in C 2h treated cells except at the 1 mg when concentrations increased, similar to other treatment times and doses.  Collectively, the evidence suggests that plant tannins appear to influence adipocyte lipid metabolic components.