H Y Huang1,2, W C Wang2,3,4, P Y Lin1, C P Huang1, C Y Chen2,3,4, Y K Chen2,3,4. 1. Department of Dentistry, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chia-Yi, Taiwan. 2. School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. 3. Oral & Maxillofacial Imaging Center, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. 4. Division of Oral Pathology & Maxillofacial Radiology, Department of Dentistry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
Abstract
AIM: To determine the expressions of hypoxia-related [hypoxia-inducible transcription factors (HIF)-1α, BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 (BNIP3) and phospho-adenosine monophosphate activated protein kinase (pAMPK)] and autophagy-related [microtubule-associated protein 1 light chain 3 (LC3), beclin-1 (BECN-1), autophagy-related gene (Atg)5-12, and p62] proteins in human inflammatory periapical lesions. METHODOLOGY: Fifteen samples of radicular cysts (RCs) and 21 periapical granulomas (PGs), combined with 17 healthy dental pulp tissues, were examined. Enzyme-linked immunosorbent assay (ELISA) was used to detect interleukin (IL)-1β cytokine; immunohistochemical (IHC) and Western blot (WB) analyses were employed to examine autophagy-related and hypoxia-related proteins. Transmission electron microscopy (TEM) was used to explore the ultrastructural morphology of autophagy in periapical lesions. Nonparametric Kruskal-Wallis tests and Mann-Whitney U-tests were used for statistical analyses. RESULTS: ELISA revealed a significantly higher (P < 0.001) IL-1β expression in periapical lesions than in normal pulp tissue. Immunoscores of IHC expressions of pAMPK, HIF-1α, BNIP3, BECN-1 and Atg5-12 proteins in periapical lesions were significantly higher (P < 0.001) (except BECN-1) than those in normal pulp tissue. The results of IHC studies were largely compatible with those of WB analyses, where significantly higher (P < 0.05) expressions of hypoxia-related and autophagy-related proteins (except BECN-1, p62 and LC3II in WB analyses) in periapical lesions were noted as compared to normal pulp tissue. Upon TEM, ultrastructural double-membrane autophagosomes and autolysosomes were observed in PGs and RCs. CONCLUSIONS: Autophagy associated with hypoxia may play a potential causative role in the development and maintenance of inflamed periapical lesions.
AIM: To determine the expressions of hypoxia-related [hypoxia-inducible transcription factors (HIF)-1α, BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 (BNIP3) and phospho-adenosine monophosphate activated protein kinase (pAMPK)] and autophagy-related [microtubule-associated protein 1 light chain 3 (LC3), beclin-1 (BECN-1), autophagy-related gene (Atg)5-12, and p62] proteins in human inflammatory periapical lesions. METHODOLOGY: Fifteen samples of radicular cysts (RCs) and 21 periapical granulomas (PGs), combined with 17 healthy dental pulp tissues, were examined. Enzyme-linked immunosorbent assay (ELISA) was used to detect interleukin (IL)-1β cytokine; immunohistochemical (IHC) and Western blot (WB) analyses were employed to examine autophagy-related and hypoxia-related proteins. Transmission electron microscopy (TEM) was used to explore the ultrastructural morphology of autophagy in periapical lesions. Nonparametric Kruskal-Wallis tests and Mann-Whitney U-tests were used for statistical analyses. RESULTS: ELISA revealed a significantly higher (P < 0.001) IL-1β expression in periapical lesions than in normal pulp tissue. Immunoscores of IHC expressions of pAMPK, HIF-1α, BNIP3, BECN-1 and Atg5-12 proteins in periapical lesions were significantly higher (P < 0.001) (except BECN-1) than those in normal pulp tissue. The results of IHC studies were largely compatible with those of WB analyses, where significantly higher (P < 0.05) expressions of hypoxia-related and autophagy-related proteins (except BECN-1, p62 and LC3II in WB analyses) in periapical lesions were noted as compared to normal pulp tissue. Upon TEM, ultrastructural double-membrane autophagosomes and autolysosomes were observed in PGs and RCs. CONCLUSIONS: Autophagy associated with hypoxia may play a potential causative role in the development and maintenance of inflamed periapical lesions.
Authors: Rokeya Tasneen; Deborah S Mortensen; Paul J Converse; Michael E Urbanowski; Anna Upton; Nader Fotouhi; Eric Nuermberger; Natalie Hawryluk Journal: Antimicrob Agents Chemother Date: 2021-06-17 Impact factor: 5.191