MyMedR

Displaying publications 1 - 20 of 41 in total

Abstract:

Sort:

Autologous chondrocyte transplantation in the repair of full-thickness focal cartilage damage in rabbits

Kamarul T, Selvaratnam L, Masjuddin T, Ab-Rahim S, Ng C, Chan KY, et al.

J Orthop Surg (Hong Kong), 2008 Aug;16(2):230-6.
PMID: 18725678

To compare the efficacy of autologous chondrocyte transplantation (ACT) versus non-operative measures for cartilage repair in rabbits.

Matched MeSH terms: Glycosaminoglycans/metabolism
Fulltext Development of decellularized meniscus using closed sonication treatment system: potential scaffolds for orthopedics tissue engineering applications

Yusof F, Sha'ban M, Azhim A

Int J Nanomedicine, 2019;14:5491-5502.
PMID: 31410000 DOI: 10.2147/IJN.S207270

PURPOSE: Meniscus is a fibrocartilagenous tissue that cannot effectively heal due to its complex structure and presence of avascular zone. Thus, tissue engineering and regenerative medicine offer an alternative for the regeneration of meniscus tissues using bioscaffolds as a replacement for the damaged one. The aim of this study was to prepare an ideal meniscus bioscaffold with minimal adverse effect on extracellular matrix components (ECMs) using a sonication treatment system.
METHODS: The decellularization was achieved using a developed closed sonication treatment system for 10 hrs, and continued with a washing process for 5 days. For the control, a simple immersion treatment was set as a benchmark to compare the decellularization efficiency. Histological and biochemical assays were conducted to investigate the cell removal and retention of the vital extracellular matrix. Surface ultrastructure of the prepared scaffolds was evaluated using scanning electron microscope at 5,000× magnification viewed from cross and longitudinal sections. In addition, the biomechanical properties were investigated through ball indentation testing to study the stiffness, residual forces and compression characteristics. Statistical significance between the samples was determined with p-value =0.05.
RESULTS: Histological and biochemical assays confirmed the elimination of antigenic cellular components with the retention of the vital extracellular matrix within the sonicated scaffolds. However, there was a significant removal of sulfated glycosaminoglycans. The surface histoarchitecture portrayed the preserved collagen fibril orientation and arrangement. However, there were minor disruptions on the structure, with few empty micropores formed which represented cell lacunae. The biomechanical properties of bioscaffolds showed the retention of viscoelastic behavior of the scaffolds which mimic native tissues. After immersion treatment, those scaffolds had poor results compared to the sonicated scaffolds due to the inefficiency of the treatment.
CONCLUSION: In conclusion, this study reported that the closed sonication treatment system had high capabilities to prepare ideal bioscaffolds with excellent removal of cellular components, and retained extracellular matrix and biomechanical properties.

Matched MeSH terms: Glycosaminoglycans/metabolism
Fulltext Poor peer support as a predictive factor towards depression among adolescent

Norfazilah, A., Hafizah, Z., Siti Zubaidah, Azmawati, M.N.

Medicine & Health, 2015;10(1):48-57.
MyJurnal

Kebelakangan ini, tanda-tanda kemurungan dalam kalangan remaja semakin meningkat. Kajian ini dijalankan untuk menentukan prevalens kemurungan dan faktor-faktor ramalan. Satu kajian keratan rentas telah dijalankan 191 remaja yang terpilih secara rawak dan terdiri daripada pelajar tingkatan empat dari lima buah sekolah menengah di negeri Selangor, Malaysia. Satu soal selidik yang terdiri daripada enam bahagian (A) demografi, (B) tahap kemurungan, (C) hubungan keluarga, (D) tahap sokongan rakan sebaya, (E) harga diri, dan (F) pencapaian akademik telah diedarkan. Prevalen kemurungan adalah 50.3%. Analisis regresi logistik mendapati, remaja yang mempunyai masalah dengan rakan-rakan adalah lebih cenderung untuk mengalami kemurungan berbanding dengan mereka yang tidak mempunyai masalah dengan rakan-rakan mereka (aOR 2.84, 95% CI 1.50, 5.36). Kajian selanjutnya perlu meneliti faktor-faktor lain seperti tekanan daripada guru-guru untuk mengukuhkan pemahaman kita mengenai kemurungan di kalangan remaja. Diharapkan hasil kajian ini berguna kepada pelbagai pihak yang mengambil berat tentang masalah ini.

Matched MeSH terms: Glycosaminoglycans
Fulltext Enterovirus 71 uses cell surface heparan sulfate glycosaminoglycan as an attachment receptor

Tan CW, Poh CL, Sam IC, Chan YF

J Virol, 2013 Jan;87(1):611-20.
PMID: 23097443 DOI: 10.1128/JVI.02226-12

Enterovirus 71 (EV-71) infections are usually associated with mild hand, foot, and mouth disease in young children but have been reported to cause severe neurological complications with high mortality rates. To date, four EV-71 receptors have been identified, but inhibition of these receptors by antagonists did not completely abolish EV-71 infection, implying that there is an as yet undiscovered receptor(s). Since EV-71 has a wide range of tissue tropisms, we hypothesize that EV-71 infections may be facilitated by using receptors that are widely expressed in all cell types, such as heparan sulfate. In this study, heparin, polysulfated dextran sulfate, and suramin were found to significantly prevent EV-71 infection. Heparin inhibited infection by all the EV-71 strains tested, including those with a single-passage history. Neutralization of the cell surface anionic charge by polycationic poly-d-lysine and blockage of heparan sulfate by an anti-heparan sulfate peptide also inhibited EV-71 infection. Interference with heparan sulfate biosynthesis either by sodium chlorate treatment or through transient knockdown of N-deacetylase/N-sulfotransferase-1 and exostosin-1 expression reduced EV-71 infection in RD cells. Enzymatic removal of cell surface heparan sulfate by heparinase I/II/III inhibited EV-71 infection. Furthermore, the level of EV-71 attachment to CHO cell lines that are variably deficient in cell surface glycosaminoglycans was significantly lower than that to wild-type CHO cells. Direct binding of EV-71 particles to heparin-Sepharose columns under physiological salt conditions was demonstrated. We conclude that EV-71 infection requires initial binding to heparan sulfate as an attachment receptor.

Matched MeSH terms: Glycosaminoglycans/metabolism*
Polysulfonate suramin inhibits Zika virus infection

Tan CW, Sam IC, Chong WL, Lee VS, Chan YF

Antiviral Res, 2017 07;143:186-194.
PMID: 28457855 DOI: 10.1016/j.antiviral.2017.04.017

Zika virus (ZIKV) is an arthropod-borne flavivirus that causes newborn microcephaly and Guillian-Barré syndrome in adults. No therapeutics are available to treat ZIKV infection or other flaviviruses. In this study, we explored the inhibitory effect of glycosaminoglycans and analogues against ZIKV infection. Highly sulfated heparin, dextran sulfate and suramin significantly inhibited ZIKV infection in Vero cells. De-sulfated heparin analogues lose inhibitory effect, implying that sulfonate groups are critical for viral inhibition. Suramin, an FDA-approved anti-parasitic drug, inhibits ZIKV infection with 3-5 log10 PFU viral reduction with IC50value of ∼2.5-5 μg/ml (1.93 μM-3.85 μM). A time-of-drug-addition study revealed that suramin remains potent even when administrated at 1-24 hpi. Suramin inhibits ZIKV infection by preventing viral adsorption, entry and replication. Molecular dynamics simulation revealed stronger interaction of suramin with ZIKV NS3 helicase than with the envelope protein. Suramin warrants further investigation as a potential antiviral candidate for ZIKV infection. Heparan sulfate (HS) is a cellular attachment receptor for multiple flaviviruses. However, no direct ZIKV-heparin interaction was observed in heparin-binding analysis, and downregulate or removal of cellular HS with sodium chlorate or heparinase I/III did not inhibit ZIKV infection. This indicates that cell surface HS is not utilized by ZIKV as an attachment receptor.

Matched MeSH terms: Glycosaminoglycans/pharmacology
Fulltext Oxygen tension modulates the effects of TNFα in compressed chondrocytes

Tilwani RK, Vessillier S, Pingguan-Murphy B, Lee DA, Bader DL, Chowdhury TT

Inflamm Res, 2017 Jan;66(1):49-58.
PMID: 27658702 DOI: 10.1007/s00011-016-0991-5

OBJECTIVE AND DESIGN: Oxygen tension and biomechanical signals are factors that regulate inflammatory mechanisms in chondrocytes. We examined whether low oxygen tension influenced the cells response to TNFα and dynamic compression.
MATERIALS AND METHODS: Chondrocyte/agarose constructs were treated with varying concentrations of TNFα (0.1-100 ng/ml) and cultured at 5 and 21 % oxygen tension for 48 h. In separate experiments, constructs were subjected to dynamic compression (15 %) and treated with TNFα (10 ng/ml) and/or L-NIO (1 mM) at 5 and 21 % oxygen tension using an ex vivo bioreactor for 48 h. Markers for catabolic activity (NO, PGE2) and tissue remodelling (GAG, MMPs) were quantified by biochemical assay. ADAMTS-5 and MMP-13 expression were examined by real-time qPCR. 2-way ANOVA and a post hoc Bonferroni-corrected t test were used to analyse data.
RESULTS: TNFα dose-dependently increased NO, PGE2 and MMP activity (all p

Matched MeSH terms: Glycosaminoglycans/metabolism
Quantitative analysis of sulphated glycosaminoglycans content of Malaysian sea cucumber Stichopus hermanni and Stichopus vastus

Masre SF, Yip GW, Sirajudeen KN, Ghazali FC

Nat Prod Res, 2012;26(7):684-9.
PMID: 21859370 DOI: 10.1080/14786419.2010.545354

Stichopus hermanni and Stichopus vastus are sea cucumber species from the Stichopodidae family within the coastal waters of Malaysia. The integument of these invertebrates is hypothesised to contain abundant glycosaminoglycans (GAGs). GAGs are divided into non-sulphated and sulphated GAGs. Sulphated GAGs have various chemico-biological functions that are beneficial to humans. This study quantitatively analysed N-, O-sulphated and total sulphated GAG content from three different anatomical regions (integument, internal organs and coelomic fluid) of S. hermanni and S. vastus. The integument revealed the highest content of total, O- and N-sulphated GAGs, followed by the internal organs and the coelomic fluid for both species of sea cucumbers. The percentage division of O- and N-sulphated GAGs suggested that anatomical parts of both species showed higher levels of O-sulphated GAGs compared to N-sulphated GAGs. In conclusion, these findings indicate that the integument body wall of S. hermanni and S. vastus is a rich source of sulphated GAGs.

Matched MeSH terms: Glycosaminoglycans/analysis*; Glycosaminoglycans/isolation & purification
Fulltext Pulsed low-intensity ultrasound increases proliferation and extracelluar matrix production by human dermal fibroblasts in three-dimensional culture

Bohari SP, Grover LM, Hukins DW

J Tissue Eng, 2015 Nov 19;6:2041731415615777.
PMID: 26668710 DOI: 10.1177/2041731415615777

This study evaluated the effect of pulsed low-intensity ultrasound on cell proliferation, collagen production and glycosaminoglycan deposition by human dermal fibroblasts encapsulated in alginate. Hoechst 33258 assay for cell number, hydroxyproline assay for collagen content, dimethylmethylene blue assay for glycosaminoglycan content and scanning electron microscopy were performed on the encapsulated cells treated with pulsed low-intensity ultrasound and a control group that remained untreated. Pulsed low-intensity ultrasound showed a significant effect on cell proliferation and collagen deposition but no consistent pattern for glycosaminoglycan content. Alcian blue staining showed that glycosaminoglycans were deposited around the cells in both treated and control groups. These results suggest that pulsed low-intensity ultrasound alone shows a positive effect on cell proliferation and collagen deposition even without growth factor supplements.

Matched MeSH terms: Glycosaminoglycans
Fulltext Persepsi pakar perubatan kesihatan awam, Kementerian Kesihatan Malaysia mengenai skim Sistem Saraan Malaysia (SSM)

Aniza, I., Syed Mohamed Aljunid, Jamsiah, M.

Malaysian Journal of Community Health, 2007;13(1):22-31.
MyJurnal

Skim Sistem Saraan Malaysia (SSM) telah diperkenalkan pada tahun 2002 menggantikan skim Sistem Saraan Baru (SSB) kepada kakitangan sektor awam. Satu kajian keratan rentas telah dijalankan ke atas Pakar Perubatan Kesihatan Awam (PPKA) pada 2004 yang bertujuan untuk mendapatkan persepsi mereka mengenai skim SSM. Semua PPKA yang berdaftar dengan Persatuan Pakar Perubatan Kesihatan Awam (PPPKA) yang berkhidmat dengan Kementerian Kesihatan Malaysia (KKM) dipilih sebagai responden. Kajian ini menggunakan borang soalselidik yang diisi sendiri oleh responden. Kadar respon kajian ini ialah 70.0% iaitu 217 responden. Kajian ini mendapati sebanyak 80.6% PPKA tidak bersetuju dengan pelaksanaan SSM, hanya 7.4% bersetuju dan sebanyak 12.0% berkecuali. Kelemahan-kelemahan utama SSM yang dikenalpasti oleh responden yang tidak bersetuju dengan SSM ialah prosedur atau skim perkhidmatan yang kabur(83.9%), peperiksaan Tahap Kecekapan yang tidak releven (54.1%) dan kenaikan pangkat terjejas (40.5%). Hasil kajian ini dapat membantu pihak-pihak yang terlibat memperbaiki kelemahan-kelemahan SSM supaya pelaksanaannya menjadi lebih mantap dan dapat menangani kelemahan yang wujud di dalam skim tersebut.

Matched MeSH terms: Glycosaminoglycans
N-O, carboxymethyl chitosan enhanced scaffold porosity and biocompatibility under e-beam irradiation at 50 kGy

Lee SY, Kamarul T

Int J Biol Macromol, 2014 Mar;64:115-22.
PMID: 24325858 DOI: 10.1016/j.ijbiomac.2013.11.039

In this study, a chitosan co-polymer scaffold was prepared by mixing poly(vinyl alcohol) (PVA), NO, carboxymethyl chitosan (NOCC) and polyethylene glycol (PEG) solutions to obtain desirable properties for chondrocyte cultivation. Electron beam (e-beam) radiation was used to physically cross-link these polymers at different doses (30 kGy and 50 kGy). The co-polymers were then lyophilized to form macroporous three-dimensional (3-D) matrix. Scaffold morphology, porosity, swelling properties, biocompatibility, expression of glycosaminoglycan (GAG) and type II collagen following the seeding of primary chondrocytes were studied up to 28 days. The results demonstrate that irradiation of e-beam at 50 kGy increased scaffold porosity and pore sizes subsequently enhanced cell attachment and proliferation. Scanning electron microscopy and transmission electron microscopy revealed extensive interconnected microstructure of PVA-PEG-NOCC, demonstrated cellular activities on the scaffolds and their ability to maintain chondrocyte phenotype. In addition, the produced PVA-PEG-NOCC scaffolds showed superior swelling properties, and increased GAG and type II collagen secreted by the seeded chondrocytes. In conclusion, the results suggest that by adding NOCC and irradiation cross-linking at 50 kGy, the physical and biological properties of PVA-PEG blend can be further enhanced thereby making PVA-PEG-NOCC a potential scaffold for chondrocytes.

Matched MeSH terms: Glycosaminoglycans/biosynthesis
Fulltext Histology, glycosaminoglycan level and cartilage stiffness in monoiodoacetate-induced osteoarthritis: comparative analysis with anterior cruciate ligament transection in rat model and human osteoarthritis

Naveen SV, Ahmad RE, Hui WJ, Suhaeb AM, Murali MR, Shanmugam R, et al.

Int J Med Sci, 2014;11(1):97-105.
PMID: 24396291 DOI: 10.7150/ijms.6964

Monosodium -iodoacetate (MIA)-induced animal model of osteoarthritis (OA) is under-utilised despite having many inherent advantages. At present, there is lack of studies that directly compare the degenerative changes induced by MIA with the surgical osteoarthritis induction method and human osteoarthritis, which would further verify a greater use of this model. Therefore, we compared the histological, biochemical and biomechanical characteristics in rat model using MIA against the anterior cruciate ligament transection (ACLT) and human cartilage with clinically established osteoarthritis. The right knees of Sprague-Dawley rats were subjected to either MIA or ACLT (n=18 in each group). Six rats were used as controls. Human cartilage samples were collected and compared from patients clinically diagnosed with (n=7) and without osteoarthritis (n=3). Histological, biochemical (Glycosaminoglycans/total protein) and biomechanical (cartilage stiffness) evaluations were performed at the end of the 1(st) and 2(nd) week after OA induction. For human samples, evaluations were performed at the time of sampling. Histopathological changes in the MIA group were comparable to that observed in the ACLT group and human OA. The Mankin scores of the 3 groups were comparable (MIA: 11.5 ± 1.0; ACLT: 10.1 ± 1.1; human OA: 13.2 ± 0.8). Comparable reduction in Glycosaminoglycan/total protein content in the intervention groups were observed (MIA: 7 ± 0.6; ACLT: 6.6 ± 0.5; human OA: 3.1 ± 0.7). Cartilage stiffness score were 24.2 ± 15.3 Mpa for MIA, 25.3 ± 4.8 for ACLT and 0.5 ± 0.0 Mpa for human OA. The MIA model produces comparable degenerative changes to ACLT and human OA with the advantage of being rapid, minimally invasive and reproducible. Therefore, wider utilisation of MIA as animal translational OA model should perhaps be advocated.

Matched MeSH terms: Glycosaminoglycans/metabolism*
Fulltext Differential protein expression between chondrogenic differentiated MSCs, undifferentiated MSCs and adult chondrocytes derived from Oryctolagus cuniculus in vitro

Tay LX, Lim CK, Mansor A, Kamarul T

Int J Med Sci, 2014;11(1):24-33.
PMID: 24396283 DOI: 10.7150/ijms.7244

This preliminary study aims to determine the differentially expressed proteins from chondrogenic differentiated multipotent stromal cells (cMSCs) in comparison to undifferentiated multipotent stromal cells (MSCs) and adult chondrocytes (ACs).

Matched MeSH terms: Glycosaminoglycans/metabolism
Treatment outcomes of alginate-embedded allogenic mesenchymal stem cells versus autologous chondrocytes for the repair of focal articular cartilage defects in a rabbit model

Tay LX, Ahmad RE, Dashtdar H, Tay KW, Masjuddin T, Ab-Rahim S, et al.

Am J Sports Med, 2012 Jan;40(1):83-90.
PMID: 21917609 DOI: 10.1177/0363546511420819

Mesenchymal stem cells (MSCs) represent a promising alternative form of cell-based therapy for cartilage injury. However, the capacity of MSCs for chondrogenesis has not been fully explored. In particular, there is presently a lack of studies comparing the effectiveness of MSCs to conventional autologous chondrocyte (autoC) treatment for regeneration of full-thickness cartilage defects in vivo.

Matched MeSH terms: Glycosaminoglycans/metabolism
Human amniotic membrane as a chondrocyte carrier vehicle/substrate: in vitro study

Krishnamurithy G, Shilpa PN, Ahmad RE, Sulaiman S, Ng CL, Kamarul T

J Biomed Mater Res A, 2011 Dec 01;99(3):500-6.
PMID: 21913317 DOI: 10.1002/jbm.a.33184

Human amniotic membrane (HAM) is an established biomaterial used in many clinical applications. However, its use for tissue engineering purposes has not been fully realized. A study was therefore conducted to evaluate the feasibility of using HAM as a chondrocyte substrate/carrier. HAMs were obtained from fresh human placenta and were process to produced air dried HAM (AdHAM) and freeze dried HAM (FdHAM). Rabbit chondrocytes were isolated and expanded in vitro and seeded onto these preparations. Cell proliferation, GAG expression and GAG/cell expression were measured at days 3, 6, 9, 12, 15, 21, and 28. These were compared to chondrocytes seeded onto plastic surfaces. Histological analysis and scanning electron microscopy was performed to observe cell attachment. There was significantly higher cell proliferation rates observed between AdHAM (13-51%, P=0.001) or FdHAM (18-48%, p = 0.001) to chondrocytes in monolayer. Similarly, GAG and GAG/cell expressed in AdHAM (33-82%, p = 0.001; 22-60%, p = 0.001) or FdHAM (41-81%, p = 0.001: 28-60%, p = 0.001) were significantly higher than monolayer cultures. However, no significant differences were observed in the proliferation rates (p = 0.576), GAG expression (p = 0.476) and GAG/cell expression (p = 0.135) between AdHAM and FdHAM. The histology and scanning electron microscopy assessments demonstrates good chondrocyte attachments on both HAMs. In conclusion, both AdHAM and FdHAM provide superior chondrocyte proliferation, GAG expression, and attachment than monolayer cultures making it a potential substrate/carrier for cell based cartilage therapy and transplantation.

Matched MeSH terms: Glycosaminoglycans/metabolism
Human amnion as a novel cell delivery vehicle for chondrogenic mesenchymal stem cells

Tan SL, Sulaiman S, Pingguan-Murphy B, Selvaratnam L, Tai CC, Kamarul T

Cell Tissue Bank, 2011 Feb;12(1):59-70.
PMID: 19953328 DOI: 10.1007/s10561-009-9164-x

This study investigates the feasibility of processed human amnion (HAM) as a substrate for chondrogenic differentiation of mesenchymal stem cells (MSCs). HAM preparations processed by air drying (AD) and freeze drying (FD) underwent histological examination and MSC seeding in chondrogenic medium for 15 days. Monolayer cultures were used as control for chondrogenic differentiation and HAMs without cell seeding were used as negative control. Qualitative observations were made using scanning electron microscopy analysis and quantitative analyses were based on the sulfated glycosaminoglycans (GAG) assays performed on day 1 and day 15. Histological examination of HAM substrates before seeding revealed a smooth surface in AD substrates, while the FD substrates exhibited a porous surface. Cell attachment to AD and FD substrates on day 15 was qualitatively comparable. GAG were significantly highly expressed in cells seeded on FD HAM substrates. This study indicates that processed HAM is a potentially valuable material as a cell-carrier for MSC differentiation.

Matched MeSH terms: Glycosaminoglycans/metabolism
Fulltext Ultra-structural changes and expression of chondrogenic and hypertrophic genes during chondrogenic differentiation of mesenchymal stromal cells in alginate beads

Dashtdar H, Murali MR, Selvaratnam L, Balaji Raghavendran H, Suhaeb AM, Ahmad TS, et al.

PeerJ, 2016;4:e1650.
PMID: 26966647 DOI: 10.7717/peerj.1650

Chondrogenic differentiation of mesenchymal stromal cells (MSCs) in the form of pellet culture and encapsulation in alginate beads has been widely used as conventional model for in vitro chondrogenesis. However, comparative characterization between differentiation, hypertrophic markers, cell adhesion molecule and ultrastructural changes during alginate and pellet culture has not been described. Hence, the present study was conducted comparing MSCs cultured in pellet and alginate beads with monolayer culture. qPCR was performed to assess the expression of chondrogenic, hypertrophic, and cell adhesion molecule genes, whereas transmission electron microscopy (TEM) was used to assess the ultrastructural changes. In addition, immunocytochemistry for Collagen type II and aggrecan and glycosaminoglycan (GAG) analysis were performed. Our results indicate that pellet and alginate bead cultures were necessary for chondrogenic differentiation of MSC. It also indicates that cultures using alginate bead demonstrated significantly higher (p < 0.05) chondrogenic but lower hypertrophic (p < 0.05) gene expressions as compared with pellet cultures. N-cadherin and N-CAM1 expression were up-regulated in second and third weeks of culture and were comparable between the alginate bead and pellet culture groups, respectively. TEM images demonstrated ultrastructural changes resembling cell death in pellet cultures. Our results indicate that using alginate beads, MSCs express higher chondrogenic but lower hypertrophic gene expression. Enhanced production of extracellular matrix and cell adhesion molecules was also observed in this group. These findings suggest that alginate bead culture may serve as a superior chondrogenic model, whereas pellet culture is more appropriate as a hypertrophic model of chondrogenesis.

Matched MeSH terms: Glycosaminoglycans
Fulltext A preliminary study comparing the use of allogenic chondrogenic pre-differentiated and undifferentiated mesenchymal stem cells for the repair of full thickness articular cartilage defects in rabbits

Dashtdar H, Rothan HA, Tay T, Ahmad RE, Ali R, Tay LX, et al.

J Orthop Res, 2011 Sep;29(9):1336-42.
PMID: 21445989 DOI: 10.1002/jor.21413

Chondrogenic differentiated mesenchymal stem cells (CMSCs) have been shown to produce superior chondrogenic expression markers in vitro. However, the use of these cells in vivo has not been fully explored. In this study, in vivo assessment of cartilage repair potential between allogenic-derived chondrogenic pre-differentiated mesenchymal stem cells and undifferentiated MSCs (MSCs) were compared. Bilateral full thickness cartilage defects were created on the medial femoral condyles of 12 rabbits (n = 12). Rabbits were divided into two groups. In one group, the defects in the right knees were repaired using alginate encapsulated MSCs while in the second group, CMSCs were used. The animals were sacrificed and the repaired and control knees were assessed at 3 and 6 months after implantation. Quantitative analysis was performed by measuring the Glycosaminoglycans (GAGs)/total protein content. The mean Brittberg score was higher in the transplanted knees as compared to the untreated knee at 6 months (p 0.05). This study demonstrates that the use of either MSC or CMSC produced superior healing when compared to cartilage defects that were untreated. However, both cells produced comparable treatment outcomes.

Matched MeSH terms: Glycosaminoglycans/metabolism
Fulltext Human peripheral blood derived mesenchymal stem cells demonstrate similar characteristics and chondrogenic differentiation potential to bone marrow derived mesenchymal stem cells

Chong PP, Selvaratnam L, Abbas AA, Kamarul T

J Orthop Res, 2012 Apr;30(4):634-42.
PMID: 21922534 DOI: 10.1002/jor.21556

The use of mesenchymal stem cells (MSCs) for cartilage repair has generated much interest owing to their multipotentiality. However, their significant presence in peripheral blood (PB) has been a matter of much debate. The objectives of this study are to isolate and characterize MSCs derived from PB and, compare their chondrogenic potential to MSC derived from bone marrow (BM). PB and BM derived MSCs from 20 patients were isolated and characterized. From 2 ml of PB and BM, 5.4 ± 0.6 million and 10.5 ± 0.8 million adherent cells, respectively, were obtained by cell cultures at passage 2. Both PB and BM derived MSCs were able to undergo tri-lineage differentiation and showed negative expression of CD34 and CD45, but positively expressed CD105, CD166, and CD29. Qualitative and quantitative examinations on the chondrogenic potential of PB and BM derived MSCs expressed similar cartilage specific gene (COMP) and proteoglycan levels, respectively. Furthermore, the s-GAG levels expressed by chondrogenic MSCs in cultures were similar to that of native chondrocytes. In conclusion, this study demonstrates that MSCs from PB maintain similar characteristics and have similar chondrogenic differentiation potential to those derived from BM, while producing comparable s-GAG expressions to chondrocytes.

Matched MeSH terms: Glycosaminoglycans/metabolism
The effect of TGF-beta1 and beta-estradiol on glycosaminoglycan and type II collagen distribution in articular chondrocyte cultures

Ab-Rahim S, Selvaratnam L, Kamarul T

Cell Biol Int, 2008 Jul;32(7):841-7.
PMID: 18479947 DOI: 10.1016/j.cellbi.2008.03.016

Articular cartilage extracellular matrix (ECM) plays a crucial role in regulating chondrocyte functions via cell-matrix interaction, cytoskeletal organization and integrin-mediated signaling. Factors such as interleukins, basic fibroblast growth factor (bFGF), bone morphogenic proteins (BMPs) and insulin-like growth factor (IGF) have been shown to modulate the synthesis of extracellular matrix in vitro. However, the effects of TGF-beta1 and beta-estradiol in ECM regulation require further investigation, although there have been suggestions that these factors do play a positive role. To establish the role of these factors on chondrocytes derived from articular joints, a study was conducted to investigate the effects of TGF-beta1 and beta-estradiol on glycosaminoglycan secretion and type II collagen distribution (two major component of cartilage ECM in vivo). Thus, chondrocyte cultures initiated from rabbit articular cartilage were treated with 10ng/ml of TGF-beta1, 10nM of beta-estradiol or with a combination of both factors. Sulphated glycosaminoglycan (GAG) and type II collagen levels were then measured in both these culture systems. The results revealed that the synthesis of GAG and type II collagen was shown to be enhanced in the TGF-beta1 treated cultures. This increase was also noted when TGF-beta1 and beta-estradiol were both used as culture supplements. However, beta-estradiol alone did not appear to affect GAG or type II collagen deposition. There was also no difference between the amount of collagen type II and GAG being expressed when chondrocyte cultures were treated with TGF-beta1 when compared with cultures treated with combined factors. From this, we conclude that although TGF-beta1 appears to stimulate chondrocyte ECM synthesis, beta-estradiol fails to produce similar effects. The findings of this study confirm that contrary to previous claims, beta-estradiol has little or no effect on chondrocyte ECM synthesis. Furthermore, the use of TGF-beta1 may be useful in future studies looking into biological mechanisms by which ECM synthesis in chondrocyte cultures can be augmented, particularly for clinical application.

Matched MeSH terms: Glycosaminoglycans/metabolism*
Chondrocyte-alginate constructs with or without TGF-β1 produces superior extracellular matrix expression than monolayer cultures

Ab-Rahim S, Selvaratnam L, Raghavendran HR, Kamarul T

Mol Cell Biochem, 2013 Apr;376(1-2):11-20.
PMID: 23238871 DOI: 10.1007/s11010-012-1543-0

Tissue engineering approaches often require expansion of cell numbers in vitro to accelerate tissue regenerative processes. Although several studies have used this technique for therapeutic purposes, a major concern involving the use of isolated chondrocyte culture is the reduction of extracellular matrix (ECM) protein expressed due to the transfer of cells from the normal physiological milieu to the artificial 2D environment provided by the cell culture flasks. To overcome this issue, the use of alginate hydrogel beads as a substrate in chondrocyte cultures has been suggested. However, the resultant characteristics of cells embedded in this bead is elusive. To elucidate this, a study using chondrocytes isolated from rabbit knee articular cartilage expanded in vitro as monolayer and chondrocyte-alginate constructs was conducted. Immunohistochemical evaluation and ECM distribution was examined with or without transforming growth factor (TGF-β1) supplement to determine the ability of cells to express major chondrogenic proteins in these environments. Histological examination followed by transmission electron microscopy and scanning electron microscopy was performed to determine the morphology and the ultrastructural characteristics of these cells. Results demonstrated a significant increase in glycosaminoglycan/mg protein levels in chondrocyte cultures grown in alginate construct than in monolayer cultures. In addition, an abundance of ECM protein distribution surrounding chondrocytes cultured in alginate hydrogel was observed. In conclusion, the current study demonstrates that the use of alginate hydrogel beads in chondrocyte cultures with or without TGF-β1 supplement provided superior ECM expression than monolayer cultures.

Matched MeSH terms: Glycosaminoglycans/metabolism

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links