Andrea C M Sinanan

University of Bedfordshire, Luton, England, United Kingdom

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Publications (21)34.3 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: SUMMARYA hypofunctional masticatory system was developed in 21-day-old male rats by feeding them a soft diet for 27 weeks. Retraining of a parallel group for 6 weeks was achieved by switching back to a hard diet after 21 weeks. A control group was fed a hard diet for 27 weeks. At the end of the experimental period, the expression levels of the myosin heavy chain isoform genes MYH 1 and 2 (fast), 3 (embryonic) and 7 (slow) in the deep masseter were compared using qRT-PCR analysis.The gene expressions of MYH 3 and MYH 7 were significantly higher in the rehabilitation group compared with the normal and hypofunctional group, but no significant differences were found in regards to the gene expression of MYH 1 and 2.Retraining made it possible for the slow (MYH 7) isoform levels to adapt to the increased mechanical load. The increased level of embryonic (MYH 3) isoform could be due to the need of creation of new MYH isoforms.
    The European Journal of Orthodontics 11/2012; · 1.08 Impact Factor
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    ABSTRACT: The mechanism whereby anabolic androgens are associated with hypertrophy of skeletal muscle is incompletely understood but may involve an interaction with locally generated insulin-like growth factor (IGF) 1. The present investigation utilized a cell culture model of human skeletal muscle-derived cell maturation to test the hypothesis that androgens increase differentiation of human muscle precursor cells in vitro and to assess effects of androgen with or without IGF-1 on IGF-1 messenger RNA (mRNA) expression in human muscle precursor cells. Differentiation of muscle-derived cells was induced under standard low-serum conditions. Cultures were then exposed to androgen (testosterone (T)) at 50, 100, and 500 nM or IGF-1 (10-50 ng·mL⁻¹). Immunocytochemistry and real-time polymerase chain reaction (RT-PCR) were used to assess effects of androgens and IGF-1 after 3- (early) or 7-d (late) muscle differentiation, respectively; RT-PCR was used to quantify the effects on androgen receptor expression. Under low-serum conditions, 3-d exposure to androgens or IGF-1 or both resulted in no significant increase in cellular myogenic commitment. After 7-d exposure, however, T and IGF-1 were both found to increase fusion index with no observable synergistic effect. T also increased IGF-1 mRNA generation (P < 0.0001), whereas exogenous IGF-1 (P < 0.001) reduced IGF-1 mRNA transcription relative to control. The T effect was reversible after treatment with flutamide, an androgen receptor antagonist. Both T and IGF-1 increase myogenic commitment after 7-d exposure to a differentiation medium. With T causing a concomitant increase in IGF-1 mRNA underpinning IGF-1 as a central mediator in the cellular pathways associated with muscle hypertrophy, including those affected by androgens. The novel system described has the potential for elucidating the pattern of growth factor effects associated with androgens in skeletal muscle.
    Medicine and science in sports and exercise 09/2011; 44(4):610-5. · 4.48 Impact Factor
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    ABSTRACT: To use various facial classifications, including either/both vertical and horizontal facial criteria, to assess their effects on the interpretation of masseter muscle (MM) gene expression. Fresh MM biopsies were obtained from 29 patients (age, 16-36 years) with various facial phenotypes. Based on clinical and cephalometric analysis, patients were grouped using three different classifications: (1) basic vertical, (2) basic horizontal, and (3) combined vertical and horizontal. Gene expression levels of the myosin heavy chain genes MYH1, MYH2, MYH3, MYH6, MYH7, and MYH8 were recorded using quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and were related to the various classifications. The significance level for statistical analysis was set at P ≤ .05. Using classification 1, none of the MYH genes were found to be significantly different between long face (LF) patients and the average vertical group. Using classification 2, MYH3, MYH6, and MYH7 genes were found to be significantly upregulated in retrognathic patients compared with prognathic and average horizontal groups. Using classification 3, only the MYH7 gene was found to be significantly upregulated in retrognathic LF compared with prognathic LF, prognathic average vertical faces, and average vertical and horizontal groups. The use of basic vertical or basic horizontal facial classifications may not be sufficient for genetics-based studies of facial phenotypes. Prognathic and retrognathic facial phenotypes have different MM gene expressions; therefore, it is not recommended to combine them into one single group, even though they may have a similar vertical facial phenotype.
    The Angle Orthodontist 08/2011; 82(2):261-6. · 1.18 Impact Factor
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    ABSTRACT: Annual Meeting of the Society-for-Experimental-Biology JUN 28-JUL 01, 2009 Glasgow, SCOTLAND Soc Expt Biol
    01/2009; 153A:S73-S73.
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    ABSTRACT: There is a clearly established relationship between masticatory muscle structure and facial form. Human studies in this area, however, have been limited, especially in consideration of the myosin heavy chain (MyHC) family of contractile proteins. The aim of this pilot study was to assess if differences were detectable between genotype with respect to MyHC isoforms and the vertical facial phenotype in a sample of nine Caucasian female patients, age range 18-49 years, using a novel rapid technique. Masseter muscle biopsies were taken from patients with a range of vertical facial form. The levels of expression of the MyHC isoform genes MYH 1, 2, 3, 6, 7, and 8 were compared with the expression in a female calibrator patient aged 23 years with normal vertical facial form, using quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. Statistical analysis was undertaken using Pearson correlation coefficient. The results showed that there were distinct differences in gene expression between patients with a wide range of variation although changes in MYH1 were consistent with one cephalometric variable, the maxillo-mandibular angle. The full procedure, from start to finish, can be completed within half a day. Rapid genotyping of patients in this way could reveal important information of relevance to treatment. This technology has potential as a diagnostic and prognostic aid when considering correction of certain malocclusions.
    The European Journal of Orthodontics 01/2009; 31(2):196-201. · 1.08 Impact Factor
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    ABSTRACT: Background Information. Functional adaptation of skeletal muscle is a requirement for different muscle groups (e.g. craniofacial, ocular, limb) to undergo site-specific changes. Such tissue remodelling depends on dynamic interactions between muscle cells and their extracellular matrix, via participation of multifunctional molecules like integrins. In view of data suggesting a role in fundamental muscle biology and muscle development in other systems, this study has focussed on expression and function of alphav integrins, in cultured adult human craniofacial muscle (masseter) precursor cells and myotubes, and the predominantly fibroblastic interstital cell population. Results and conclusions. Flow cytometric and immunofluorescence phenotyping show that alphav, alphavbeta3 and alphavbeta5, are expressed in all mononuclear cells (muscle precursors and interstitial cells) seeded on muscle extracellular molecules such as gelatin, vitronectin and fibronectin. In this system, blockade of alphav activity using a function perturbing antibody abrogates cell migration on vitronectin and fibronectin. alphav integrins act predominantly as vitronectin receptors as cell-substrate attachment is diminished when alphav neutralizing agents are introduced into cultures seeded on vitronectin, and this inhibition is reversible; these integrins also appear to be minor fibronectin receptors. These results demonstrate that the alphav subset of integrins present on both myogenic precursors and interstitial cells, is an essential cohort of vitronectin and, to a lesser extent, fibronectin receptors mediating cell adhesion and either directly or indirectly, arbiters of cell motilty.
    Biology of the Cell 12/2008; · 3.49 Impact Factor
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    ABSTRACT: BACKGROUND INFORMATION: Functional adaptation of skeletal muscle is a requirement for different muscle groups (e.g. craniofacial, ocular and limb) to undergo site-specific changes. Such tissue remodelling depends on dynamic interactions between muscle cells and their extracellular matrix, via participation of multifunctional molecules such as integrins. In view of data suggesting a role in fundamental muscle biology and muscle development in other systems, the present study has focused on expression and function of alpha v integrins, in cultured adult human craniofacial muscle (masseter) precursor cells and myotubes, and the predominantly fibroblastic IC (interstitial cells) population. RESULTS AND CONCLUSIONS: Flow-cytometric phenotyping and immunofluorescence phenotyping show that alpha v, alpha v beta 3 and alpha v beta 5 are expressed in all mononuclear cells (muscle precursors and IC) seeded on muscle extracellular molecules such as gelatin, VN (vitronectin) and FN (fibronectin). In this system, blockade of alpha v activity using a function-perturbing antibody abrogates cell migration on VN and FN. alpha v integrins act predominantly as VN receptors as cell-substrate attachment is diminished when alpha v neutralizing agents are introduced into cultures seeded on VN, and this inhibition is reversible; these integrins also appear to be minor FN receptors. These results demonstrate that the alpha v subset of integrins present on both myogenic precursors and IC is an essential cohort of VN and, to a lesser extent, FN receptors mediating cell adhesion and, either directly or indirectly, arbiters of cell motility.
    Biology of the Cell 09/2008; 100(8):465-77. · 3.49 Impact Factor
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    ABSTRACT: The effects of muscle splice variants of insulin-like growth factor I (IGF-I) on proliferation and differentiation were studied in human primary muscle cell cultures from healthy subjects as well as from muscular dystrophy and ALS patients. Although the initial numbers of mononucleated progenitor cells expressing desmin were lower in diseased muscle, the E domain peptide of IGF-IEc (MGF) significantly increased the numbers of progenitor cells in healthy and diseased muscle. IGF-I significantly enhances myogenic differentiation whereas MGF E peptide blocks this pathway, resulting in an increased progenitor (stem) cell pool and thus potentially facilitating repair and maintenance of this postmitotic tissue.
    FEBS Letters 07/2007; 581(14):2727-32. · 3.58 Impact Factor
  • Nigel Hunt, Rishma Shah, Andrea Sinanan, Mark Lewis
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    ABSTRACT: Hunt, Nigel
    l Orthodontie Française 07/2007; 78(2):79-88.
  • Nigel Hunt, Rishma Shah, Andrea Sinanan, Mark Lewis
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    ABSTRACT: The British Orthodontic Society invites outstanding contributors from the field of Orthodontics to give the guest lecture in memory of George Northcroft. In 2005 the guest lecturer was Professor Nigel Hunt. The article that follows was presented as the Northcroft Memorial Lecture 2005 at the World Orthodontic Congress, Paris.
    Journal of orthodontics 10/2006; 33(3):187-97.
  • Andrea C M Sinanan, Paul G Buxton, Mark P Lewis
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    ABSTRACT: Skeletal muscle is one of the few adult tissues that possesses the capacity for regeneration (restoration of lost functional tissue) as opposed to repair. This capacity is due to the presence of 'muscle stem cells' known as satellite cells. Detailed investigation of these cells over the past 50 years has revealed that both these and other cells within the skeletal muscle complex are capable of regenerating both muscle and other cell types as well. Here, we review this information, and suggest that skeletal muscle is an exciting reservoir of cells for regenerating skeletal muscle itself, as well as other cell types.
    Biology of the Cell 05/2006; 98(4):203-14. · 3.49 Impact Factor
  • R Shah, A C M Sinanan, J C Knowles, N P Hunt, M P Lewis
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    ABSTRACT: The current technique to replace missing craniofacial skeletal muscle is the surgical transfer of local or free flaps. This is associated with donor site morbidity, possible tissue rejection and limited supply. The alternative is to engineer autologous skeletal muscle in vitro, which can then be re-implanted into the patient. A variety of biomaterials have been used to engineer skeletal muscle with limited success. This study investigated the use of phosphate-based glass fibres as a potential scaffold material for the in vitro engineering of craniofacial skeletal muscle. Human masseter (one of the muscles of mastication)--derived cell cultures were used to seed the glass fibres, which were arranged into various configurations. Growth factors and matrix components were to used to manipulate the in vitro environment. Outcome was determined with the aid of microscopy, time-lapse footage, immunofluorescence imaging and CyQUANT proliferation, creatine kinase and protein assays. A 3-dimensional mesh arrangement of the glass fibres was the best at encouraging cell attachment and proliferation. In addition, increasing the density of the seeded cells and using Matrigel and insulin-like growth factor I enhanced the formation of prototypic muscle fibres. In conclusion, phosphate-based glass fibres can support the in vitro engineering of human craniofacial muscle.
    Biomaterials 06/2005; 26(13):1497-505. · 8.31 Impact Factor
  • Andrea C M Sinanan, Nigel P Hunt, Mark P Lewis
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    ABSTRACT: Skeletal muscle has been well characterized as a reservoir of myogenic precursors or satellite cells with the potential to participate in cellular repopulation therapies for muscle dysfunction. Recent evidence, however, suggests that the postnatal muscle compartment can be considered an alternative to bone marrow as a source of multipotent cells or muscle-derived stem cells (MDSCs). MDSCs, when primed with appropriate environmental cues, can differentiate into a variety of non-muscle cells. The present study describes the application of a new technique for the isolation of adult human myoblasts and putative MDSCs, based on microbead-immunomagnetic selection of CD56+ cells, derived from craniofacial skeletal muscle, and details changes in morphological/molecular phenotype of the purified cells when maintained in either a myogenic or a non-myogenic milieu. Multiple immunofluorescence microscopy and two-colour flow-cytometric analysis of proliferating CD56+ cultures revealed positive staining for myogenic markers (CD56, desmin and M-cadherin) as well as putative stem-cell markers [the antigens CD34, CD90 and CD106, and Flk-1 (fetal liver kinase-1)/VEGFR-2 (vascular-endothelial-growth-factor receptor)]. Confluent cultures subjected to cycles of adipogenic or osteogenic induction contained either adipocytes or osteoblasts and myotubes. In conclusion, the CD56+ subpopulation within adult human skeletal muscle is heterogeneous and is composed of both lineage-committed myogenic cells and multipotent cells (the candidate MDSCs), which are able to form non-muscle tissue such as fat and bone.
    Biotechnology and Applied Biochemistry 09/2004; 40(Pt 1):25-34. · 1.35 Impact Factor
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    ABSTRACT: Successful adaptation of craniofacial skeletal muscle is dependent upon the connective tissue component of the muscle. This is exemplified by procedures such as distraction histo/osteogenesis. The mechanisms underlying remodelling of intramuscular connective tissue are complex and multifactorial and involve extracellular matrix (ECM) molecules, receptors for the ECM (integrins) and enzymes that remodel the ECM (MMPs). This review discusses the current state of knowledge and clinical implications of connective tissue biology as applied to craniofacial skeletal muscle.
    European Journal Of Oral Sciences 09/2001; 109(4):209-21. · 1.42 Impact Factor
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    ABSTRACT: The remodelling of connective tissue components is a fundamental requirement for a number of pivotal processes in cell biology. These may include myoblast migration and fusion during development and regeneration. In other systems, similar biological processes are facilitated by secretion of the matrix metalloproteinases (MMPs), especially the gelatinases. This study investigated the activity of the gelatinases MMP-2 and 9 by zymography on cell conditioned media in cultures of cells derived from explants of the human masseter muscle and in the murine myoblast cell-line C2C12. Expression of MMP-9 by western blotting and TIMP-1, the major inhibitor of MMPs, by northern blotting, during all phases of myoblast proliferation, migration, alignment and fusion, was also measured. Irrespective of the origin of the cultures, MMP-9 activity was secreted only by single cell and pre-fusion cultures whilst MMP-2 activity was secreted at all stages as well as by myotubes. The loss of MMP-9 activity was due to the loss of MMP-9 protein expression. TIMP-1 mRNA was not detectable at the single cell stage but its expression increased as cells progressed through the pre-fusion and post-fusion stages to reach a maximal in myotube containing cultures. Migration of cells derived from human masseter muscle was inhibited, using a specific anti-MMP-9 blocking monoclonal antibody (6-6B). These data are consistent with the concept that regulation of matrix turnover via MMP-9 may be involved in the events leading to myotube formation, including migration. Loss of expression of this enzyme and expression of TIMP-1 mRNA is associated with myotube containing cultures. Consequently, the ratio between MMPs and TIMPs maybe important in determining myoblast migration and differentiation.
    Journal of Muscle Research and Cell Motility 05/2000; 21(3):223-33. · 1.36 Impact Factor
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    Nigel Hunt, Rishma Shah, Andrea Sinanan, Mark Lewis
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    ABSTRACT: Times Cited: 0
    79:591-591.
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    ABSTRACT: Conference of the Tissue-Engineering-and-Regenerative-Medicine-International-Society (TERMIS-EU) SEP 04-07, 2007 London, ENGLAND Tissue Engn & Regenerat Med Int Soc, European Chapter; UK Tissue & Cell Engn Soc
    13:1681-1682.
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    ABSTRACT: Export Date: 13 December 2011
  • Nigel Hunt, Rishma Shah, Andrea Sinanan, Mark Lewis

Publication Stats

219 Citations
34.30 Total Impact Points

Institutions

  • 2011
    • University of Bedfordshire
      • Institute for Sport and Physical Activity Research
      Luton, England, United Kingdom
  • 2005–2009
    • UCL Eastman Dental Institute
      Londinium, England, United Kingdom
  • 2004–2007
    • University College London
      • • Department of Cell and Developmental Biology
      • • Eastman Dental Institute
      London, ENG, United Kingdom