Taurine Augments Telomerase Activity and Promotes Chondrogenesis in Dental Pulp Stem Cells
Authors: Mohamed Jamal
Mohammed Mashyakhy
A Thirumal Raj
Abdulaziz S Abumelha
Hitesh Chohan
Shilpa Bhandi
Vikrant R Patil
Sultan Binalrimal
Rodolfo Reda
Ahmed Alkahtani
Reham Jamal Sharroufna
Shankargouda Patil
Mazen F Alkahtany
Ali Robaian
Luca Testarelli
Journal: Journal of Personalized Medicine (2021)
Discipline: CLINICAL MEDICINE
Keywords: chondrogenesis; dental pulp; mesenchymal stem cells; regenerative medicine; taurine
Affiliations: Department of Restorative Dental Sciences, College of Dentistry, Jazan University, Jazan 45412, Saudi Arabia., Department of Restorative Dental Sciences, Division of Endodontics, College of Dentistry, King Saud University, Riyadh 11451, Saudi Arabia., Department of Restorative Dental Sciences, College of Dentistry, King Khalid University, Abha 61421, Saudi Arabia., Private Hospital, Khobar 122001, Saudi Arabia., Department of Endodontics, Hamdan Bin Mohamed College of Dental Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai Health Care City, Dubai 66566, United Arab Emirates., Conservative Dental Sciences Department, College of Dentistry, Prince Sattam Bin Abdulaziz University, Alkharj 11942, Saudi Arabia., Restorative Department, College of Dentistry, Riyadh Elm University, Riyadh 12611, Saudi Arabia., Biogenre Private Limited, Pune 412105, India., Department of Oral Pathology and Microbiology, Sri Venkateswara Dental College and Hospital, Chennai 600130, India., Department of Oral and Maxillofacial Sciences, Sapienza University, University of Rome, 00185 Rome, Italy., Department of Maxillofacial Surgery and Diagnostic Sciences, Division of Oral Pathology, College of Dentistry, Jazan University, Jazan 45412, Saudi Arabia.

Abstract:  Background: Stem cell therapy has become an advanced and state-of-the-art procedure to regenerate lost tissues of the human body. Cartilage repair is a challenging task in which stem cells find potential application. One of the important biologic modifiers that can cause chondrogenic differentiation of stem cells is taurine. However, taurine has not been investigated for its effects on dental pulp derived stem cell (DPSC) chondrogenic differentiation. Objective: The objective of the study was to investigate if taurine administration to DPSCs heralds chondrogenic differentiation as ascertained by expression of SOX9, COL2A1, ACAN, ELN, and COMP. The study also investigated if the differentiated cells synthesized glycosaminoglycans, a marker of cartilage formation. The study also aimed to assess proliferative activity of the cells after taurine administration by measuring the hTERT gene and protein expression. Materials and methods: DPSCs were obtained from a molecular biology laboratory and characterization of stem cell markers was done by flow cytometry. The cells were subjected to a MTT assay using various concentrations of taurine. Following this, hTERT gene and protein estimation was done in the control, telomerase inhibitor treated DPSC (TI-III), 10 μM taurine treated DPSC, and TI-III + 10 μM taurine treated DPSCs. A polymerase chain reaction was done to assess gene expression of SOX9, COL2A1, ACAN, ELN, and COMP genes and glycosaminoglycans were estimated in control cells, Induced DPSCs, induced and TI-III treated DPSCs, and 10 μM taurine treated DPSCs. Results: DPSCs expressed CD73, CD90, and CD105 and did not express CD34, CD45, and HLA-DR, which demonstrated that they were mesenchymal stem cells. The MTT assay revealed that various concentrations of taurine did not affect the cell viability of DPSCs. A concentration of 10 μM of taurine was used for further assays. With regard to the hTERT gene and protein expression, the taurine treated cells expressed the highest levels that were statistically significant compared to the other groups. Taurine was also found to restore hTERT expression in telomerase inhibitor treated cells. With regard to chondrogenesis related genes, taurine administration significantly increased the expression of SOX9, COL2A1, ACAN, and ELN genes in DPSCs and caused a significant increase in glycosaminoglycan production by the cells. Conclusions: Taurine can be regarded a biologic modifier that can significantly augment chondrogenic differentiation of DPSCs and can find potential applications in regenerative medicine in the area of cartilage regeneration. 

Retracted: No

PubPeer comments:
 This paper is one of at least 30 papers by the same research group that all share the same photo. In all papers, this photo is used as a zoomed-in inset representing the high-resolution transmission electron microscopy (HRTEM) analysis of the  atomic lattice fringe and particle size of the nanoparticles. Of concern, the same photo is used to represent a different type of nanoparticle in each of these papers. Here is a collage of 6 different uses of the same photo,  Inset 1 : ![file] Here is a list of the 30 papers identified so far that all use this photo, and the different types of nanoparticles that they represent. * Aysenur Aygun et al. - DOI: 10.1016 j.jpba.2019.112961 - Nigella sativa Pt * Aysun Su0327avk et al. - DOI: 10.1016 j.molliq.2019.112355 - PtNi@AC * Aysun Su0327avk et al. - DOI: 10.1016 j.msec.2019.01.113 - ZnNi@f-MWCNT * Aysun Su0327avk et al. - DOI: 10.1038 s41598-019-55746-y - PdNi@rGO * Betuu0308l Su0327en et al. - DOI: 10.1016 j.ijhydene.2018.03.175 - Pd@GO * Betuu0308l Su0327en et al. - DOI: 10.1016 j.nanoso.2017.08.013 - PdRu@GO * Betuu0308l Su0327en et al. - DOI: 10.1016 j.apcatb.2017.11.067 - RhPt TC@GO * Betuu0308l Su0327en et al. - DOI: 10.1016 j.ijhydene.2018.07.081 - Pd-Ir@AC * Betuu0308l Su0327en et al. - DOI: 10.1016 j.jcis.2018.05.021 - Ru-Ni@PVP * Betuu0308l Su0327en et al. - DOI: 10.1016 j.nanoso.2018.07.008 - Pd@AC * Betuu0308l Su0327en et al. - DOI: 10.1016 j.ijhydene.2018.07.122 - PdRuNi@GO * Betuu0308l Su0327en et al. - DOI: 10.1016 j.ijhydene.2019.01.215 - PdCo@GO * Betuu0308l Su0327en et al. - DOI: 10.1016 j.jtice.2019.04.040 - PdNi@VC * Betuu0308l Su0327en et al. - DOI: 10.1016 j.ijhydene.2018.12.051 - PdCo@MOF * Betuu0308l Su0327en et al. - DOI: 10.1016 j.ijhydene.2019.02.176 - RuCu@rGO * Birguu0308tay Su0327ahin et al. - DOI: 10.1016 j.colsurfb.2017.12.042 - Pt * Buse Demirkan et al. - DOI: 10.1038 s41598-020-59935-y - rGO Pd@PPy * Buse Demirkan et al. - DOI: 10.1038 s41598-019-48802-0 - Pt-Co@rGO * Fatma Diler et al. - DOI: 10.1016 j.molliq.2019.111967 - Pd@GO * Hayriye Genc Bilgicli et al. - DOI: 10.1016 j.micromeso.2020.110014 - CPG * Hilal Acidereli et al. - DOI: 10.1016 j.renene.2020.07.105 - PdRu@G * Mehmet Salih Nas et al. - DOI: 10.1016 j.molliq.2019.112100 - Pt-Co@GO * Nabih Lolak et al. - DOI: 10.1021 acsomega.9b00485 - PdNi@GO * Oznur Alptekin et al. - DOI: 10.1039 D0CY00641F - PtRh@GO * Rukiye Ayranci et al. - DOI: 10.1016 j.msec.2019.02.040 - Pt Ni@rGO * Sait Bozkurt et al. - DOI: 10.1016 j.aca.2017.07.051 - Pd TNM@rGO * Sinan Eris et al. - DOI: 10.1016 j.jcis.2017.11.085 - Pt@f-CB * Sinan Eris et al. - DOI: 10.1016 j.ijhydene.2017.11.063 - Pt@f-VC * Suat Tacu0327yu0131ldu0131z et al. - DOI: 10.1016 j.molliq.2019.04.019 - Ru-Rh@PVP * Zeynep Dasu0327delen et al. - DOI: 10.1016 j.apcatb.2017.08.014 - Pt@GO-PVP Here is Figure 2 of this paper: ![file] , 
 Figure 2 (shown above) also looks very similar to Figure 2 of Hilal Aciderel et al., DOI: 10.1016 j.renene.2020.07.105; https: pubpeer.com publications 64C20A4E41BA25E4889FE9420210E9. Left: Figure 2 from Betul Sen et al. (this paper). Right: Figure 2 from Hilal Aciderel et al. ![file] , 
 This paper is one of 4 (so far) showing the same XPS Pd 3d spectrum. Only two of the four papers are about PdRuNi@GO. ![file] https: doi.org 10.1038 s41598-019-55746-y https: pubpeer.com publications 6389B57905710C7A5B59C6673547D7 http: dx.doi.org 10.1016 j.nanoso.2017.08.013 https: pubpeer.com publications 7A123B2F1443D6AC355E4B633E05E2 2017 DOI: 10.1039 C6RA13142E https: pubpeer.com publications 333B326822135A21713764E73A2B86 2016 ,