title: Up-regulation of niacinamide in intervertebral disc aggrecan in vitro.
abstract: The regulatory effects of niacinamide (Nia) on intervertebral disc (IVD) aggrecan in vitro was investigated. Chiba's 10 ng/mL interleukin-1 (IL-1)-induced rabbit IVD degeneration model in vitro was established. 0.5, 0.25 and 0.05 mg/mL Nia was added to normal and degenerated IVDs for intervention. On the first and second week after intervention, safranin O-fast green staining intensity and glycosaminoglycan (GS) content were measured. The expression of aggrecan core protein was detected by RT-PCR. The results showed: (1) After treatment with 0.5 mg/mL Nia for one week, the GS content in nucleus pulposus (NP) was increased by 44.8% as compared with control group (P < 0 01); The GS content in IL-1 induction groups was increased with the increase of Nia concentrations: After treatment with 0.5 mg/mL for one week, the GS content in NP was increased by 68.3% as compared with control group (P < 0.01). After two weeks, GS content in NP and fibrous rings was still higher than in control group at the same period (P < 0.01) and untreated group (P < 0.01). (2) Safranin O-fast green staining revealed that with the increase of Nia concentrations, staining density in NP and fibrous rings was increased and histological structure damage to IVDs by IL-1beta was alleviated. (3) RT-PCR showed that the expression of core protein gene in IL-1beta-induced degenerated IVDS was increased with the increase of Nia concentrations. It was concluded that under conditions in vitro, Nia could up-regulate the expression of aggrecan in IVDs and protect IVDs from IL-1beta-induced degeneration at least partially, which offers a potential choice for IVD degeneration clinical therapy.
authors.affiliation: Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
authors.forename: Xiaoqian
authors.initials: X
authors.lastname: Xiong
authors.forename: Shuhua
authors.initials: S
authors.lastname: Yang
authors.forename: Zengwu
authors.initials: Z
authors.lastname: Shao
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.forename: Zirui
authors.initials: Z
authors.lastname: Zhan
authors.forename: Deyu
authors.initials: D
authors.lastname: Duan
mesh_terms: D053674:Aggrecans; D000818:Animals; D002478:Cells, Cultured; D011508:Chondroitin Sulfate Proteoglycans / Q000096:biosynthesis* / Q000235:genetics; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis* / Q000235:genetics; D006025:Glycosaminoglycans / Q000096:biosynthesis / Q000235:genetics; D007375:Interleukin-1 / Q000494:pharmacology; D007403:Intervertebral Disc / Q000166:cytology / Q000378:metabolism* / Q000473:pathology; D037181:Lectins, C-Type / Q000096:biosynthesis* / Q000235:genetics; D009536:Niacinamide / Q000494:pharmacology*; D011817:Rabbits; D015854:Up-Regulation
chemical_list: D053674:Aggrecans; D011508:Chondroitin Sulfate Proteoglycans; D016326:Extracellular Matrix Proteins; D006025:Glycosaminoglycans; D007375:Interleukin-1; D037181:Lectins, C-Type; D009536:Niacinamide