scholarly journals Nicotinamide Phosphoribosyltransferase Inhibitor APO866 Prevents IL-1β-Induced Human Nucleus Pulposus Cell Degeneration via Autophagy

2018 ◽  
Vol 49 (6) ◽  
pp. 2463-2482 ◽  
Author(s):  
Changgui Shi ◽  
Huiqiao Wu ◽  
Di Du ◽  
Hee-Jeong Im ◽  
Ying Zhang ◽  
...  

Background/Aims: Intervertebral discs consist of an extracellular matrix (ECM) with a central gelatinous nucleus pulposus (NP) enclosed in an outer layer known as the annulus fibrosus. ECM metabolic disorders result in loss of boundary between the annulus fibrosus and NP, which can lead to intervertebral disc degeneration (IDD). Proinflammatory cytokines, such as interleukin (IL)-1β, mediate the progression of IDD. Nicotinamide phosphoribosyltransferase (Nampt) catalyzes the first step in the biosynthesis of nicotinamide adenine dinucleotide (NAD) and is known to be induced by IL-1β. APO866 is an inhibitor of NAD biosynthesis and is involved in autophagy. LC3 (microtubule-associated protein 1 light chain 3) is a key regulator of autophagy and is used as an indicator of increased autophagy. Herein, we investigate the role of APO866 in regulating autophagy in NP cells and IL-1β mediated NP cell degeneration and apoptosis. Methods: NP cells were extracted from IDD tissues and cultured in DMEM/F12 medium. Nampt was induced by different concentrations of IL-1β (0, 0.5, 1, 5, 10 ng/mL) for 24 h or NP cells were treated with 10 ng/mL IL-1β for 0, 6, 12, 48 h. QRT-PCR and western blots were used to detect Nampt and ECM-related protein expression in NP tissue of patients with IDD and in NP cells. Confocal analysis was used to detect membrane-bound LC3, Aggrecan, and Collagen II. Results: Nampt is expressed in NP tissue at higher levels in severe grades of IDD (Grade IV and V) compared with low grades (Grade II and III). In NP cells, 10 ng/mL IL-1β induced Nampt expression for 48 h, increased expression of the degradative-associated proteins, ADAMTS4/5 and MMP-3/13, and decreased expression of ECM-related proteins, Aggrecan and Collagen II. However, the Nampt inhibitor APO866 blocked IL-1β induction, and the knockdown of Nampt expression increased the expression of ECM proteins that were inhibited by IL-1β. Moreover, evidence provided by the autophagic markers LC3 and Beclin-1 indicated that APO866 induced NP cell autophagy. Furthermore, although APO866 inhibited the downregulated expression of ECM-related proteins by IL-1β, this function was blocked by autophagy inhibitor, 3-methyladenine. Conclusion: APO866 protects NP cells and induces autophagy by inhibiting IL-1β-induced NP cell degeneration and apoptosis, which may have therapeutic potential in IDD.

2012 ◽  
Vol 2 (1) ◽  
pp. 6 ◽  
Author(s):  
Marie Klauser ◽  
Franck Forterre ◽  
Marcus Doherr ◽  
Andreas Zurbriggen ◽  
David Spreng ◽  
...  

Disc degeneration occurs commonly in dogs. A variety of factors is thought to contribute an inappropriate disc matrix that isolate cells in the disc and lead to apoptosis. Disc herniation with radiculopathy and discogenic pain are the results of the degenerative process. The objective of this prospective study was to determine the extent of apoptosis in intact and herniated intervertebral discs of chondrodystrophic dogs and non-chondrodystrophic dogs. In addition, the nucleus pulposus (NP) was histologically compared between non-chondrodystrophic and chondrodystrophic dogs. Thoracolumbar intervertebral discs and parts of the extruded nucleus pulposus were harvested from 45 dogs. Samples were subsequently stained with haematoxylin-eosin and processed to detect cleaved caspase-3 and poly(ADP-ribose) polymerase. A significant greater degree of apoptosis was observed in herniated NPs of chondrodystrophic dogs compared to non- chondrodystrophic dogs with poly (ADP-ribose) polymerase and cleaved caspase- 3 detection. Within the group of chondrodystrophic dogs, dogs with an intact disc and younger than 6 years showed a significant lower incidence of apoptosis in the NP compared to the herniated NP of chondrodystrophic dogs. The extent of apoptosis in the annulus fibrosus was not different between the intact disc from chondrodystrophic and non- chondrodystrophic dogs. An age-related increase of apoptotic cells in NP and annulus fibrosus was found in the intact non-herniated intervertebral discs. Histologically, absence of notochordal cells and occurrence of chondroid metaplasia were observed in the nucleus pulposus of chondrodystrophic dogs. As a result, we found that apoptosis plays a role in disc degeneration in chondrodystrophic dogs.


Neurosurgery ◽  
2018 ◽  
Vol 85 (2) ◽  
pp. E350-E359 ◽  
Author(s):  
Ibrahim Hussain ◽  
Stephen R Sloan ◽  
Christoph Wipplinger ◽  
Rodrigo Navarro-Ramirez ◽  
Micaella Zubkov ◽  
...  

AbstractBACKGROUNDOur group has previously demonstrated in vivo annulus fibrosus repair in animal models using an acellular, riboflavin crosslinked, high-density collagen (HDC) gel.OBJECTIVETo assess if seeding allogenic mesenchymal stem cells (MSCs) into this gel yields improved histological and radiographic benefits in an in vivo sheep model of annular injury.METHODSFifteen lumbar intervertebral discs (IVDs) were randomized into 4 groups: intact, injury only, injury + acellular gel treatment, or injury + MSC-seeded gel treatment. Sheep were sacrificed at 6 wk. Disc height index (DHI), Pfirrmann grade, nucleus pulposus area, and T2 relaxation time (T2-RT) were calculated for each IVD and standardized to healthy controls from the same sheep. Quantitative histological assessment was also performed using the Han scoring system.RESULTSAll treated IVDs retained gel plugs on gross assessment and there were no adverse perioperative complications. The MSC-seeded gel treatment group demonstrated statistically significant improvement over other experimental groups in DHI (P = .002), Pfirrmann grade (P < .001), and T2-RT (P = .015). There was a trend for greater Han scores in the MSC-seeded gel-treated discs compared with injury only and acellular gel-treated IVDs (P = .246).CONCLUSIONMSC-seeded HDC gel can be delivered into injured IVDs and maintained safely in live sheep to 6 wk. Compared with no treatment and acellular HDC gel, our data show that MSC-seeded HDC gel improves outcomes in DHI, Pfirrmann grade, and T2-RT. Histological analysis shows improved annulus fibrosus and nucleus pulposus reconstitution and organization over other experimental groups as well.


2015 ◽  
Vol 84 (3) ◽  
pp. 157-166
Author(s):  
Witold Woźniak ◽  
Małgorzata Grzymisławska ◽  
Joanna Łupicka ◽  
Małgorzata Bruska ◽  
Adam Piotrowski ◽  
...  

Introduction. In the vast literature concerning the development of the intervertebral discs controversies exist as to the period of differentiation and structure of the nucleus pulposus and annulus fibrosus. These controversies result from different determination of age of the investigated embryos. Aim. Using embryos from departmental collection age of which was established according to international Carnegie staging and expressed in postfertilizational days, the differentiation of the intervertebral discs was traced. Material and methods. Study was performed on 34 embryos at developmental stages 13–23 (32–56 days). Embryos were serially sectioned in sagittal, frontal and horizontal planes. Sections were stained with various histological methods and impregnated with silver.Results. Division of sclerotomes into loose cranial and dense caudal zones (sclerotomites) was observed in embryos aged 32 days (stage 13). The intervertebral disc developed from the dense zone of sclerotome and was well recognized in embryos aged 33 days (stage 14). At the end of fifth week (embryos at stage 15, 36 days) the annulus fibrosus and the nucleus pulposus were seen. The annulus fibrosus differentiated into lateral and medial zones. Within the lateral zone cells were arranged into circular rows. These rows were considered as the first stage of laminar structure. In further developmental stages the laminae occupied both zones of the annulus fibrosus.Conclusions. The intervertebral discs develop from the dense zone of the sclerotome which is evident in embryos at stage 13 (32 days). Discs differentiate in embryos aged 33 days, when the nucleus pulposus and annulus fibrosus are recognized. In embryos aged 36 days in the annulus fibrosus circular rows forming laminar arrangement are seen.


Author(s):  
David T. Korda ◽  
Delphine Perie ◽  
James C. Iatridis

The intervertebral disc provides flexibility and load support for the spine. It consists of two main regions; the outer annulus fibrosus which is a highly organized collagen matrix and the inner nucleus pulposus which (in a healthy disc) is a proteoglycan rich gelatinous material. The predominant mode of loading on the intervertebral disc is axial compression, which generates hydrostatic pressures within the disc. The high water content of the nucleus plays a major role in supporting these loads. With age and degeneration, the water content of the nucleus changes, and is believed to significantly impact its ability to bear load. The purpose of this study therefore, was to define the effects of swelling conditions (which affect disc hydration) on the material properties of the disc under compressive loading.


2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Jun Ge ◽  
Quan Zhou ◽  
Junjie Niu ◽  
Yingjie Wang ◽  
Qi Yan ◽  
...  

Melatonin, a neuroendocrine hormone secreted by the pineal body, has a positive effect on intervertebral disc degeneration. The present study is aimed at investigating the biological role of melatonin in intervertebral disc degeneration and its underlying mechanism. A human nucleus pulposus cell (NPC) line was exposed to melatonin at different concentrations. Cell proliferation was measured by CCK-8 assay. Cell cycle and apoptosis were analyzed by flow cytometry. Western blot was performed to measure the protein expression of indicated genes. A rabbit model of intervertebral disc degeneration was established to detect the role and mechanism of melatonin on intervertebral disc degeneration. Our study showed that melatonin promoted NPC viability and inhibited cell arrest. Furthermore, melatonin treatment led to the upregulation of collagen II and aggrecan and downregulation of collagen X. Moreover, melatonin significantly elevated the activity of the ERK signaling pathway. Inhibition of the ERK1/2 signals reversed the role of melatonin in the regulation of NPCs both in vitro and in vivo. Melatonin increased NPC viability through inhibition of cell cycle arrest and apoptosis. Moreover, melatonin promoted the secretion of functional factors influencing the nucleus pulposus cell physiology and retarded cell degeneration. Our results suggest that melatonin activated the ERK1/2 signaling pathway, thereby affecting the biological properties of the intervertebral disc degeneration.


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Hongze Chang ◽  
Hongzhang Wang ◽  
Xiaolong Yang ◽  
Kemin You ◽  
Mingwei Jiang ◽  
...  

Nucleus pulposus (NP) is the core substance to maintain the homeostasis of intervertebral disc and stability of biomechanics. The insufficient supply of nutrition (especially glucose) is an important factor that leads to the degeneration of NP cells. circRNAs play an important role in the process of intervertebral disc degeneration (IDD) by regulating the functions of NP cells. However, glucose deprivation-related circRNAs and their functions in IDD have not been reported. In this study, the differentially expressed circRNAs in NP cells after 0, 6, 12, and 24 h of glucose deprivation culture were detected by a microarray assay. Besides, time series clustering analysis by STEM software obtained the differentially up- and downregulated circRNAs during glucose deficiency. Then, the main functions and pathways of up- and downregulated circRNAs were predicted by the functional enrichment analysis. By constructing the circRNA-miRNA regulatory network, the potential mechanisms of the most differentially expressed circRNAs were predicted. In addition, according to in vitro validation, circ_0075062 was upregulated in degenerating NP tissues and glucose deprivation-induced NP cell degeneration. Based on Sanger sequencing and RNase tolerance assay, circ_0075062 was the circular transcript. Interfering with circ_0075062 expression could potentially alleviate the imbalance of extracellular matrix (ECM) synthesis and degradation in the NP cells induced by glucose deprivation. Together, these findings help us gain a comprehensive understanding of the underlying mechanisms of IDD, and circ_0075062 may be a promising therapeutic target of IDD.


2021 ◽  
Author(s):  
Audrey McAlinden ◽  
David M Hudson ◽  
Aysel A Fernandes ◽  
Soumya Ravindran ◽  
Russell J Fernandes

For next generation tissue-engineered constructs and regenerative medicine to succeed clinically, the basic biology and extracellular matrix composition of tissues that these repair techniques seek to restore have to be fully determined. Using the latest reagents coupled with tried and tested methodologies, we continue to uncover previously undetected structural proteins in mature intervertebral disc. In this study we show that the ″embryonic″ type IIA procollagen isoform (containing a cysteine-rich amino propeptide) was biochemically detectable in the annulus fibrosus of both calf and mature steer intervertebral discs, but not in the nucleus pulposus where the type IIB isoform was predominantly localized. Specifically, the triple-helical type IIA procollagen isoform immunolocalized in the outer margins of the inner annulus fibrosus. Triple helical processed type II collagen exclusively localized within the inter- lamellae regions and with type IIA procollagen in the intra-lamellae regions. Mass spectrometry of the a1(II) collagen chains from the region where type IIA procollagen localized showed high 3-hydroxylation of Proline-944, a post- translational modification that is correlated with thin collagen fibrils as in the nucleus pulposus. The findings implicate small diameter fibrils of type IIA procollagen in select regions of the annulus fibrosus where it likely contributes to the organization of collagen bundles and structural properties within the type I- type II collagen transition zone.


Sign in / Sign up

Export Citation Format

Share Document