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Andrew Tsin
Title Chair and Associate Dean
Faculty Rank Professor
Degree PhD
Institution University of Texas Rio Grande Valley
Department Biomedical Sciences
Clusters Cancer
Cardiovascular and Related Diseases
Community Engagement
Genes and Environmental Health/Toxicology
HIV/AIDS
Informatics
Infectious and Immunological Diseases
Neurological Disorders and Mental Health
Obesity and Metabolic Syndromes
Women's Health and Reproductive Biology
Other
Address
1210 W. Schunior St
City Edingburg
State TX
Postal Code 78541
Telephone 9566656599
Fax
Email
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Other Positions icon

Title Adjunct Professor
Institution UTSA
Department Biology
 
Title Adjunct Professor
Institution UTH-San Antonio
Department Biochemistry

Awards and Honors icon

2011 White House Office of Science and Technology Presidential Award for Excellence in Mathematics, Science and Engineering Mentoring
2014 American Association for the Advancement of Science Mentor Award for Lifetime Achievement
2018 American Society of Biochemistry and Molecular Biology Ruth Kirschtein Diversity of Science Award

Narrative icon

  Research Interests – Dr. Andrew Tsin

Eye Disease Development: Diabetic Retinopathy & Age-Related Macular Degeneration
An recent emphasis of our vision research laboratory is to learn how hyperglycemia and/or insulin induce vascular endothelial growth factor (VEGF) secretion by retinal cells. Retinal pigment epithelial cells, retinal pericytes, and endothelial cells are maintained in culture. Growth factors such as VEGF, transforming growth factor (TGF), and bone morphological proteins (BMP) are assayed for protein end-product using ELISA. The expression of these proteins is measured by RNA protection assays. We are particularly interested in the effect of BMP-4, TGB-ß, and PEDF on the secretion of VEGF by retinal cells. Our long term goal is to learn how cytokines mediate angiogenesis leading to diabetic retinopathy or age-related macular degeneration.

Biochemistry of the Cone Visual Cycle in the Eye
A major emphasis of our laboratory is to investigate the mechanism of pigment regeneration in the cone visual system. Upon light adaptation, cone pigments are bleached to initiate electrical signals in the cone photoreceptors. These signals are then transmitted by neurons to the brain for color visual perception. In order to sustain such visual function, cone pigment must be regenerated in-situ but the underlying mechanism of this cone pigment regeneration is not known. Using animals models, the kinetics of cone pigment bleaching and regeneration are studied in details using biochemical methods. The cellular mechanisms of cone pigment regeneration are also studied using Muller cells and retinal pigment epithelial cells in culture. Specifically, we focus on the abilities of these cells to esterify, isomerize and oxidize the vitamin A (retinoid) chromophore of cone visual pigments.

Mentorship icon

 
Availability Date:
Tuesday, September 12, 2017

Dr. Tsin is personally and professionally committee to mentoring STEM workforce and diversity in science.

I am available to mentor as:
  • Biomedical Research
  • Professional Development
Contact Information for Mentoring:
  • email: Andrew.tsin@utrgv.edu
  • Phone: 956 665 6599

Programs, Membership, and Biomedical Research icon

Mentoring Mentor

NIH Awarded Grants icon

  Research projects funded by the National Institutes of Health (NIH), the Centers for Disease Control (CDC), the Food and Drug Administration (FDA), and the Department of Veterans Affairs (VA)

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1.
2013RCMI Center for Interdiscplinary Health Research CIHR5G12MD007591-14
2.
2012RCMI Center for Interdiscplinary Health Research CIHR3G12MD007591-13S1
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2012RCMI Center for Interdiscplinary Health Research CIHR8G12MD007591-13
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2011RCMI Center for Interdiscplinary Health Research CIHR5G12RR013646-12
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2011CORE A: ADMINISTRATIVE CORE5G12RR013646-12
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2010CORE A: ADMINISTRATIVE CORE2G12RR013646-11
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2009CORE A: ADMINISTRATIVE CORE3G12RR013646-10S1
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2006UTSA MBRS SCORE Program5S06GM008194-27
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2005UTSA MBRS SCORE Program5S06GM008194-26
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2004UTSA MBRS SCORE Program5S06GM008194-25
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2004UTSA MBRS SCORE Program3S06GM008194-25S1
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2004Pathways of the Cone Visual Cycle3S06GM008194-25S1
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2003UTSA MBRS SCORE Program2S06GM008194-24
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2002The UTSA MBRS SCORE Program3S06GM008194-22S2
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2002MOLECULAR BIOLOGY OF 11CIS RETNYL ESTER HYDROLASE5K14GM000670-05
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2002UTSA MBRS SCORE PROGRAM5S06GM008194-23
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200211 CIS RETINAL ESTER HYDROLASE IN THE EYE5S06GM008194-23
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2001UTSA MBRS SCORE PROGRAM5S06GM008194-22
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200111 CIS RETINAL ESTER HYDROLASE IN THE EYE3S06GM008194-22S3
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2001MOLECULAR BIOLOGY OF 11CIS RETNYL ESTER HYDROLASE5K14GM000670-04
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2001The UTSA MBRS SCORE Program3S06GM008194-22S3
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200111 CIS RETINAL ESTER HYDROLASE IN THE EYE5S06GM008194-22
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2000MOLECULAR BIOLOGY OF 11CIS RETNYL ESTER HYDROLASE5K14GM000670-03
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200011 CIS RETINAL ESTER HYDROLASE IN THE EYE5S06GM008194-21
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2000UTSA MBRS SCORE PROGRAM5S06GM008194-21
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200011 CIS RETINAL ESTER HYDROLASE IN THE EYE3S06GM008194-21S2
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1999MOLECULAR BIOLOGY OF 11CIS RETNYL ESTER HYDROLASE5K14GM000670-02
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199911 CIS RETINAL ESTER HYDROLASE IN THE EYE2S06GM008194-20
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1999UTSA MBRS SCORE PROGRAM2S06GM008194-20
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1998MINORITIES RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM5S06GM008194-19
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1998MOLECULAR BIOLOGY OF 11CIS RETNYL ESTER HYDROLASE1K14GM000670-01
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199811 CIS RETINAL ESTER HYDROLASE IN THE EYE5S06GM008194-19
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199711 CIS RETINAL ESTER HYDROLASE IN THE EYE5S06GM008194-18
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1997MINORITIES RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM5S06GM008194-18
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1996MINORITIES IN RESEARCH AND SCIENCE ACHIEVMENT PROGRAM3S06GM008194-17S2
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1996MINORITIES RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM3S06GM008194-17S4
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1996MINORITIES RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM5S06GM008194-17
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1996MINORITIES IN RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM3S06GM008194-17S3
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1996MINORITES IN RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM3S06GM008194-17S1
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1995MINORITIES RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM2S06GM008194-16
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199511-CIS-RETINYL ESTER HYDROLASE IN THE EYE5R01EY006438-06
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1995MINORITIES IN RESEARCH AND SCIENCE ACHIEVEMENT3S06GM008194-16S1
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199411-CIS-RETINYL ESTER HYDROLASE IN THE EYE3R01EY006438-04A3S1
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1994MINORITIES IN RESEARCH AND SCIENCE ACHIEVEMENT3S06GM008194-15S1
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199411-CIS-RETINYL ESTER HYDROLASE IN THE EYE5R01EY006438-05
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1994MINORITIES IN RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM5S06GM008194-15
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199311-CIS-RETINYL ESTER HYDROLASE IN THE EYE2R01EY006438-04A3
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1993MINORITIES IN RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM5S06GM008194-14
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1992MINORITIES IN RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM3S06GM008194-13S1
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1992MINORITY HIGH SCHOOL STUDENT RESEARCH APPRENTICE PROGRAM2S03RR003243-11
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1992MINORITIES IN RESEARCH AND SCIENCE ACHIEVEMENT PROGRAM5S06GM008194-13
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1991MINORITIES IN RESEARCH AND SCIENCE ACHIEVEMENT2S06GM008194-12
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1988LOCALIZATION OF RETINYL PALMITATE HYDROLASE IN THE EYE5R01EY006438-03
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1987LOCALIZATION OF RETINYL PALMITATE HYDROLASE IN THE EYE5R01EY006438-02
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1986LOCALIZATION OF RETINYL PALMITATE HYDROLASE IN THE EYE1R01EY006438-01

Publications icon

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1. Bermea KC, Rodríguez-García A, Tsin A, Barrera-Saldaña HA. Somatolactogens and diabetic retinopathy. Growth Horm IGF Res. 2018 Feb 06.
2. Pérez-Ibave DC, Rodríguez-Sánchez IP, Garza-Rodríguez ML, Pérez-Maya AA, Luna M, Arámburo C, Tsin A, Perry G, Mohamed-Noriega K, Mohamed-Noriega J, Cavazos-Adame H, Mohamed-Hamsho J, Barrera-Saldaña HA. Expression of growth hormone gene in the baboon eye. Exp Eye Res. 2018 Apr; 169:157-169.
3. Betts-Obregon BS, Salinas M, Oladunni D, Negrete GR, Tsin AT. Chemical Modification of Ginsenoside on Cell Viability and Cytokine Secretion. Curr Aging Sci. 2017; 10(1):68-75.
4. Grigsby JG, Allen DM, Ferrigno AS, Vellanki S, Pouw CE, Hejny WA, Tsin ATC. Autocrine and Paracrine Secretion of Vascular Endothelial Growth Factor in the Pre-Hypoxic Diabetic Retina. Curr Diabetes Rev. 2017; 13(2):161-174.
5. Aryan N, Betts-Obregon BS, Perry G, Tsin AT. Oxidative Stress Induces Senescence in Cultured RPE Cells. Open Neurol J. 2016; 10:83-7.
6. Betts-Obregon BS, Mondragon AA, Mendiola AS, LeBaron RG, Asmis R, Zou T, Gonzalez-Fernandez F, Tsin AT. TGFß induces BIGH3 expression and human retinal pericyte apoptosis: a novel pathway of diabetic retinopathy. Eye (Lond). 2016 Dec; 30(12):1639-1647.
7. Pedraza FJ, Avalos JC, Yust BG, Tsin A, Sardar DK. Effect of surface coating of KYb2F7:Tm(3+) on optical properties and biomedical applications. Nanotechnology. 2016 Sep 23; 27(38):385601.
8. Gonzalez-Fernandez F, Betts-Obregon B, Tsin AT, DeSa RJ. Technical brief: Pump-probe paradigm in an integrating cavity to study photodecomposition processes. Mol Vis. 2016; 22:953-8.
9. Moritz RJ, LeBaron RG, Phelix CF, Rupaimoole R, Kim HS, Tsin A, Asmis R. Macrophage TGF-ß1 and the Proapoptotic Extracellular Matrix Protein BIGH3 Induce Renal Cell Apoptosis in Prediabetic and Diabetic Conditions. Int J Clin Med. 2016 Jul; 7(7):496-510.
10. Wambo TO, Chen LY, McHardy SF, Tsin AT. Molecular dynamics study of human carbonic anhydrase II in complex with Zn(2+) and acetazolamide on the basis of all-atom force field simulations. Biophys Chem. 2016 Jul-Aug; 214-215:54-60.
11. Betts-Obregon BS, Vellanki S, Buikema J, Tsin AT, Wright K. Effect of Glucose on Retinal Endothelial Cell Viability and VEGF Secretion. HSOA J Cell Biol Cell Metabol. 2016; 3(1).
12. Vellanki S, Ferrigno A, Alanis Y, Betts-Obregon BS, Tsin AT. High Glucose and Glucose Deprivation Modulate Müller Cell Viability and VEGF Secretion. Int J Ophthalmol Eye Sci. 2016 Feb; 4(2):178-183.
13. Gonzalez-Fernandez F, Betts-Obregon B, Yust B, Mimun J, Sung D, Sardar D, Tsin AT. Interphotoreceptor retinoid-binding protein protects retinoids from photodegradation. Photochem Photobiol. 2015 Mar-Apr; 91(2):371-8.
14. Mondragon AA, Betts-Obregon BS, Moritz RJ, Parvathaneni K, Navarro MM, Kim HS, Lee CF, LeBaron RG, Asmis R, Tsin AT. BIGH3 protein and macrophages in retinal endothelial cell apoptosis. Apoptosis. 2015 Jan; 20(1):29-37.
15. Betts-Obregon BS, Gonzalez-Fernandez F, Tsin AT. Interphotoreceptor retinoid-binding protein (IRBP) promotes retinol uptake and release by rat Müller cells (rMC-1) in vitro: implications for the cone visual cycle. Invest Ophthalmol Vis Sci. 2014 Sep 02; 55(10):6265-71.
16. Grigsby JG, Cardona SM, Pouw CE, Muniz A, Mendiola AS, Tsin AT, Allen DM, Cardona AE. The role of microglia in diabetic retinopathy. J Ophthalmol. 2014; 2014:705783.
17. Pedraza F, Yust B, Tsin A, Sardar D. NIR to NIR upconversion in KYb2F7: RE3+ (RE = Tm, Er) nanoparticles for biological imaging. Proc SPIE Int Soc Opt Eng. 2014 Feb 01; 8956.
18. Gonzalez-Fernandez F, Sung D, Haswell KM, Tsin A, Ghosh D. Thiol-dependent antioxidant activity of interphotoreceptor retinoid-binding protein. Exp Eye Res. 2014 Mar; 120:167-74.
19. Muñiz A, Greene WA, Plamper ML, Choi JH, Johnson AJ, Tsin AT, Wang HC. Retinoid uptake, processing, and secretion in human iPS-RPE support the visual cycle. Invest Ophthalmol Vis Sci. 2014 Jan 09; 55(1):198-209.
20. Godoy DL, Betts-Obregon BS, Tsin AT. Ginsenoside-Rb1 Inhibition of VEGF Release - Structure and Activity Relations (SAR) Perspective. Med Hypothesis Discov Innov Ophthalmol. 2014; 3(2):38-9.
21. Yust BG, Sardar DK, Mimun LC, Gangadharan AK, Tsin AT. Rare Earth doped nanoparticles in imaging and PDT. Proc SPIE Int Soc Opt Eng. 2013 Feb 19; 8594.
22. Barrera FJ, Yust B, Mimun LC, Nash KL, Tsin AT, Sardar DK. Optical and spectroscopic properties of human whole blood and plasma with and without Y2O3 and Nd³?:Y2O3 nanoparticles. Lasers Med Sci. 2013 Nov; 28(6):1559-66.
23. Obregon ID, Betts-Obregon BS, Yust B, Pedraza F, Ortiz A, Sardar D, Tsin AT. Effect of Silver Coating on Barium Titanium Oxide Nanoparticle Toxicity. Adv Mat Res. 2013; 787:404-407.
24. Yust BG, Razavi N, Pedraza F, Elliott Z, Tsin AT, Sardar DK. Enhancement of nonlinear optical properties of BaTiO3 nanoparticles by the addition of silver seeds. Opt Express. 2012 Nov 19; 20(24):26511-20.
25. Parvathaneni K, Grigsby JG, Betts BS, Tsin AT. Estrogen-induced retinal endothelial cell proliferation: possible involvement of pigment epithelium-derived factor and phosphoinositide 3-kinase/mitogen-activated protein kinase pathways. J Ocul Pharmacol Ther. 2013 Feb; 29(1):27-32.
26. Grigsby J, Betts B, Vidro-Kotchan E, Culbert R, Tsin A. A possible role of acrolein in diabetic retinopathy: involvement of a VEGF/TGFß signaling pathway of the retinal pigment epithelium in hyperglycemia. Curr Eye Res. 2012 Nov; 37(11):1045-53.
27. Betts BS, Obregon I, Tsin AT. Cultured Müller cells from mammals can synthesize and accumulate retinyl esters. Exp Eye Res. 2012 Aug; 101:56-9.
28. Betts BS, Parvathaneni K, Yendluri BB, Grigsby J, Tsin AT. Ginsenoside-Rb1 Induces ARPE-19 Proliferation and Reduces VEGF Release. ISRN Ophthalmol. 2011; 2011:184295.
29. Grigsby JG, Parvathaneni K, Almanza MA, Botello AM, Mondragon AA, Allen DM, Tsin AT. Effects of tamoxifen versus raloxifene on retinal capillary endothelial cell proliferation. J Ocul Pharmacol Ther. 2011 Jun; 27(3):225-33.
30. Vidro-Kotchan E, Yendluri BB, Le-Thai T, Tsin A. NBHA reduces acrolein-induced changes in ARPE-19 cells: possible involvement of TGFß. Curr Eye Res. 2011 Apr; 36(4):370-8.
31. Yust BG, Sardar DK, Tsin A. A Comparison of Methods for Determining Optical Properties of Thin Samples. Proc SPIE Int Soc Opt Eng. 2010 Feb 11; 7562.
32. Muniz A, Betts BS, Trevino AR, Buddavarapu K, Roman R, Ma JX, Tsin AT. Evidence for two retinoid cycles in the cone-dominated chicken eye. Biochemistry. 2009 Jul 28; 48(29):6854-63.
33. Sardar DK, Yust BG, Barrera FJ, Mimun LC, Tsin AT. Optical absorption and scattering of bovine cornea, lens and retina in the visible region. Lasers Med Sci. 2009 Nov; 24(6):839-47.
34. Vidro EK, Gee S, Unda R, Ma JX, Tsin A. Glucose and TGFbeta2 modulate the viability of cultured human retinal pericytes and their VEGF release. Curr Eye Res. 2008 Nov; 33(11):984-93.
35. Muniz A, Villazana-Espinoza ET, Hatch AL, Trevino SG, Allen DM, Tsin AT. A novel cone visual cycle in the cone-dominated retina. Exp Eye Res. 2007 Aug; 85(2):175-84.
36. Sardar DK, Swanland GY, Yow RM, Thomas RJ, Tsin AT. Optical properties of ocular tissues in the near infrared region. Lasers Med Sci. 2007 Mar; 22(1):46-52.
37. Heimsath EG, Unda R, Vidro E, Muniz A, Villazana-Espinoza ET, Tsin A. ARPE-19 cell growth and cell functions in euglycemic culture media. Curr Eye Res. 2006 Dec; 31(12):1073-80.
38. Muniz A, Villazana-Espinoza ET, Thackeray B, Tsin AT. 11-cis-Acyl-CoA:retinol O-acyltransferase activity in the primary culture of chicken Muller cells. Biochemistry. 2006 Oct 10; 45(40):12265-73.
39. Vogt RR, Unda R, Yeh LC, Vidro EK, Lee JC, Tsin AT. Bone morphogenetic protein-4 enhances vascular endothelial growth factor secretion by human retinal pigment epithelial cells. J Cell Biochem. 2006 Aug 01; 98(5):1196-202.
40. Villazana-Espinoza ET, Hatch AL, Tsin AT. Effect of light exposure on the accumulation and depletion of retinyl ester in the chicken retina. Exp Eye Res. 2006 Oct; 83(4):871-6.
41. Trevino SG, Villazana-Espinoza ET, Muniz A, Tsin AT. Retinoid cycles in the cone-dominated chicken retina. J Exp Biol. 2005 Nov; 208(Pt 21):4151-7.
42. Sardar DK, Yow RM, Tsin AT, Sardar R. Optical scattering, absorption, and polarization of healthy and neovascularized human retinal tissues. J Biomed Opt. 2005 Sep-Oct; 10(5):051501.
43. Trevino SG, Schuschereba ST, Bowman PD, Tsin A. Lecithin:retinol acyltransferase in ARPE-19. Exp Eye Res. 2005 Jun; 80(6):897-900.
44. Sardar DK, Salinas FS, Perez JJ, Tsin AT. Optical characterization of bovine retinal tissues. J Biomed Opt. 2004 May-Jun; 9(3):624-31.
45. Chen M, Thomson AB, Tsin AT, Basu TK. The hepatic retinyl ester hydrolase activity is depressed at the onset of diabetes in BB rats. Br J Nutr. 2003 Feb; 89(2):231-8.
46. Tsin A, Mata N, Villazana E, Vidro E. New developments in the visual cycle: functional role of 11-cis retinyl esters in the retinal pigment epithelium. Hong Kong J Ophthalmol. 2001 Oct; 5(1):25-29.
47. Lu J, Dixon WT, Tsin AT, Basu TK. The metabolic availability of vitamin A is decreased at the onset of diabetes in BB rats. J Nutr. 2000 Aug; 130(8):1958-62.
48. Gamble MV, Mata NL, Tsin AT, Mertz JR, Blaner WS. Substrate specificities and 13-cis-retinoic acid inhibition of human, mouse and bovine cis-retinol dehydrogenases. Biochim Biophys Acta. 2000 Jan 03; 1476(1):3-8.
49. Tsin AT, Mata NL, Ray JA, Villazana ET. Substrate specificities of retinyl ester hydrolases in retinal pigment epithelium. Methods Enzymol. 2000; 316:384-400.
50. Mata NL, Tsin AT. Distribution of 11-cis LRAT, 11-cis RD and 11-cis REH in bovine retinal pigment epithelium membranes. Biochim Biophys Acta. 1998 Oct 02; 1394(1):16-22.
51. Mata NL, Villazana ET, Tsin AT. Colocalization of 11-cis retinyl esters and retinyl ester hydrolase activity in retinal pigment epithelium plasma membrane. Invest Ophthalmol Vis Sci. 1998 Jul; 39(8):1312-9.
52. Mata JR, Mata NL, Tsin AT. Substrate specificity of retinyl ester hydrolase activity in retinal pigment epithelium. J Lipid Res. 1998 Mar; 39(3):604-12.
53. Sena LP, Vanderjagt DJ, Rivera C, Tsin AT, Muhamadu I, Mahamadou O, Millson M, Pastuszyn A, Glew RH. Analysis of nutritional components of eight famine foods of the Republic of Niger. Plant Foods Hum Nutr. 1998; 52(1):17-30.
54. Mata NL, Mata JR, Tsin AT. Comparison of retinyl ester hydrolase activities in bovine liver and retinal pigment epithelium. J Lipid Res. 1996 Sep; 37(9):1947-52.
55. Ziari SA, Mireles VL, Cantu CG, Cervantes M, Idrisa A, Bobsom D, Tsin AT, Glew RH. Serum vitamin A, vitamin E, and beta-carotene levels in preeclamptic women in northern nigeria. Am J Perinatol. 1996 Jul; 13(5):287-91.
56. Tuitoek PJ, Ziari S, Tsin AT, Rajotte RV, Suh M, Basu TK. Streptozotocin-induced diabetes in rats is associated with impaired metabolic availability of vitamin A (retinol). Br J Nutr. 1996 Apr; 75(4):615-22.
57. Bustamante JJ, Ziari S, Ramirez RD, Tsin AT. Retinyl ester hydrolase and the visual cycle in the chicken eye. Am J Physiol. 1995 Dec; 269(6 Pt 2):R1346-50.
58. Tuitoek P, Lakey J, Rajotte R, Ziari S, Tsin A, Basu T. Effect of Insulin Treatment or Zinc Supplementation on Vitamin A Status in Streptozotocin-Induced Diabetic Rats. J Clin Biochem Nutr. 1995; 19:165-173.
59. Sun JH, Reiter RJ, Hattori A, Yaga K, Herbert DC, Tsin AT. Phototransduction-related circadian changes in indoleamine metabolism in the chick pineal gland in vivo. J Pineal Res. 1993 Oct; 15(3):132-7.
60. Suzsuki T, Terakita A, Tsin AT. RETINOID METABOLISM AND CONVERSION OF RETINOL TO DEHYDRORETINOL IN THE CRAYFISH (PROCAMBARUS CLARKII) RETINA. Comp Biochem Physiol B. 1993 Jun; 105(2):257-261.