@article {Skrzypczak-Jankun:2010:1107-3756:45, title = "Theaflavin digallate inactivates plasminogen activator inhibitor: Could tea help in Alzheimer's disease and obesity?", journal = "International Journal of Molecular Medicine", parent_itemid = "infobike://sp/ijmm", publishercode ="sp", year = "2010", volume = "26", number = "1", publication date ="2010-07-01T00:00:00", pages = "45-50", itemtype = "ARTICLE", issn = "1107-3756", eissn = "1791-244X", url = "https://www.ingentaconnect.com/content/sp/ijmm/2010/00000026/00000001/art00007", doi = "doi:10.3892/ijmm_00000433", author = "Skrzypczak-Jankun and Jankun", abstract = "Proteolysis in general and particularly the serine proteases are causally involved in many physiological processes and different diseases. Recently it was reported that plasminogen activator inhibitor type one (PAI-1) inactivation can alleviate the symptoms of Alzheimer's disease and reduce the body weight of obese individuals. In our broad search for natural compounds and their derivatives that can inhibit PAI-1, we include the polyphenols of teas since teas (green and black) or their components have been reported to alleviate the symptoms of both obesity and Alzheimer's disease. Inactivation of PAI-1 was measured in human plasma using thromboelastography. We used known PAI-1 inhibitor PAI039 [{1-benzyl-5-[4-(trifluoromethoxy) phenyl]-1H-indol-3-yl}(oxo)acetic acid] as a positive control and (-)-epigallo-catechin-3-gallate (EGCG), its prodrug octaacetate EGCG (OcAc EGCG) and theaflavin digallate [TH(2)] as potential PAI-1 inhibitors. We found that inactivation of PAI-1 in plasma by EGCG and OcAc EGCG was low or very low. However, TH(2) inactivated PAI-1 in a concentration-dependent manner with an IC50 of 18 \textmuM which is equal to or better than the IC50 reported for known PAI-1 inhibitor PAI039. Clearly TH(2) inhibits PAI-1 and might play a role in slowing down the progression of Alzheimer's disease or obesity by a PAI-1-dependent pathway. While the clinical value of TH(2) has not been proven, long-term prospective studies assessing its efficacy are warranted due to the benign nature of the substance.", }