TNF and periodontitis: The regulation of periodontitis by the active ingredients of the Asarum–Angelica drug pair may be closely related to the targets of tumor necrotizing factor (TNF), serine/threonine protein kinase (AKT1), jun proto-oncogene, AP-1 transcription factor subunit (JUN), RELA proto-oncogene (RELA), prostaglandin endoperoxide synthase 2 (PTGS2), and Caspase 3 (CASP3).