PMID- 27581091 OWN - NLM STAT- MEDLINE DCOM- 20170131 LR - 20181113 IS - 1472-6882 (Electronic) IS - 1472-6882 (Linking) VI - 16 IP - 1 DP - 2016 Aug 31 TI - The role of kaempferol-induced autophagy on differentiation and mineralization of osteoblastic MC3T3-E1 cells. PG - 333 LID - 10.1186/s12906-016-1320-9 [doi] LID - 333 AB - BACKGROUND: Kaempferol, a kind of flavonol, has been reported to possess various osteogenic biological activities, such as inhibiting bone resorption of osteoclasts and promoting the differentiation and mineralization of preosteoblasts. However, the precise cellular mechanism of action of kaempferol in osteogenesis is elusive. Autophagy is a major intracellular degradation system, which plays an important role in cell growth, survival, differentiation and homeostasis in mammals. Recent studies showed that autophagy appeared to be involved in the degradation of osteoclasts, osteoblasts and osteocytes, potentially pointing to a new pathogenic mechanism of bone homeostasis and bone marrow disease. The potential correlation between autophagy, osteogenesis and flavonoids is unclear. METHODS: The present study verified that kaempferol promoted osteogenic differentiation and mineralization and that it elevated osteogenic gene expression based on alkaline phosphatase (ALP) activity, alizarin red staining and quantitative PCR. And then we found that kaempferol induced autophagy by acridine orange (AO) and monodansylcadaverine (MDC) staining and autophagy-related protein expression. The correlation between kaempferol-induced autophagy and the osteogenic process was confirmed by the autophagy inhibitor 3-methyladenine (3-MA). RESULTS: Kaempferol promoted the proliferation, differentiation and mineralization of osteoblasts at a concentration of 10 muM. Kaempferol showed cytotoxic properties at concentrations above 50 muM. Concentrations above 10 muM decreased ALP activity, whereas those up to 10 muM increased ALP activity. Kaempferol at concentrations up to 10 muM also increased the expression of the osteoblast- activated factors RUNX-2, osterix, BMP-2 and collagen I according to RT-PCR analyses. 10 muM or less, the higher of the concentration and over time, kaempferol promoted the activity of osteoblasts. Kaempferol induced autophagy. It also increased the expression of the autophagy-related factors beclin-1, SQSTM1/p62 and the conversion of LC3-II from LC3-I. The application of 3-MA decreased the activity of ALP and the autophagy induced by kaempferol. In the RT-PCR analysis, the expression of RUNX-2, osterix, BMP-2 and collagen I was decreased. CONCLUSION: The present study showed that kaempferol stimulated the osteogenic differentiation of cultured osteoblasts by inducing autophagy. FAU - Kim, In-Ryoung AU - Kim IR AUID- ORCID: 0000-0003-0232-0385 AD - Department of Oral Anatomy, School of Dentistry, Pusan National University, Busandaehak-ro, 49, Mulguem-eup, Yangsan-si, Gyeongsangnam-do, 626-870, South Korea. FAU - Kim, Seong-Eon AU - Kim SE AD - Department of Oral and Maxillofacial Surgery, Pusan National University Dental Hospital, 20, Geumo-ro, Mulgeum-eup, Yangsan-si, Gyeongsangnam-do, 626-770, South Korea. FAU - Baek, Hyun-Su AU - Baek HS AD - Department of Oral and Maxillofacial Surgery, Pusan National University Dental Hospital, 20, Geumo-ro, Mulgeum-eup, Yangsan-si, Gyeongsangnam-do, 626-770, South Korea. FAU - Kim, Bok-Joo AU - Kim BJ AD - Deptment of Oral and Maxillofacial Surgery, Medical center, Dong-A University, 26, Daesingongwon-ro, Seo-gu, Busan, 602-715, South Korea. FAU - Kim, Chul-Hoon AU - Kim CH AD - Deptment of Oral and Maxillofacial Surgery, Medical center, Dong-A University, 26, Daesingongwon-ro, Seo-gu, Busan, 602-715, South Korea. FAU - Chung, In-Kyo AU - Chung IK AD - Department of Oral and Maxillofacial Surgery, Pusan National University Dental Hospital, 20, Geumo-ro, Mulgeum-eup, Yangsan-si, Gyeongsangnam-do, 626-770, South Korea. FAU - Park, Bong-Soo AU - Park BS AD - Department of Oral Anatomy, School of Dentistry, Pusan National University, Busandaehak-ro, 49, Mulguem-eup, Yangsan-si, Gyeongsangnam-do, 626-870, South Korea. parkbs@pusan.ac.kr. FAU - Shin, Sang-Hun AU - Shin SH AD - Department of Oral and Maxillofacial Surgery, Pusan National University Dental Hospital, 20, Geumo-ro, Mulgeum-eup, Yangsan-si, Gyeongsangnam-do, 626-770, South Korea. ssh8080@pusan.ac.kr. LA - eng PT - Journal Article DEP - 20160831 PL - England TA - BMC Complement Altern Med JT - BMC complementary and alternative medicine JID - 101088661 RN - 0 (Flavonoids) RN - 0 (Kaempferols) RN - 5142-23-4 (3-methyladenine) RN - 731P2LE49E (kaempferol) RN - JAC85A2161 (Adenine) SB - IM MH - Adenine/analogs & derivatives/pharmacology MH - Animals MH - Autophagy/*drug effects MH - Cell Differentiation/*drug effects MH - Cell Line MH - Flavonoids/*pharmacology MH - Kaempferols/*pharmacology MH - Mice MH - Osteogenesis/drug effects PMC - PMC5007678 OTO - NOTNLM OT - Autophagy OT - Flavonoids OT - Kaemferol OT - Osteogenesis EDAT- 2016/09/02 06:00 MHDA- 2017/02/01 06:00 PMCR- 2016/08/31 CRDT- 2016/09/02 06:00 PHST- 2016/04/14 00:00 [received] PHST- 2016/08/25 00:00 [accepted] PHST- 2016/09/02 06:00 [entrez] PHST- 2016/09/02 06:00 [pubmed] PHST- 2017/02/01 06:00 [medline] PHST- 2016/08/31 00:00 [pmc-release] AID - 10.1186/s12906-016-1320-9 [pii] AID - 1320 [pii] AID - 10.1186/s12906-016-1320-9 [doi] PST - epublish SO - BMC Complement Altern Med. 2016 Aug 31;16(1):333. doi: 10.1186/s12906-016-1320-9.