title: Fourier transform infrared spectroscopic imaging of cardiac tissue to detect collagen deposition after myocardial infarction.
abstract: Myocardial infarction often leads to an increase in deposition of fibrillar collagen. Detection and characterization of this cardiac fibrosis is of great interest to investigators and clinicians. Motivated by the significant limitations of conventional staining techniques to visualize collagen deposition in cardiac tissue sections, we have developed a Fourier transform infrared imaging spectroscopy (FT-IRIS) methodology for collagen assessment. The infrared absorbance band centered at 1338  cm(-1), which arises from collagen amino acid side chain vibrations, was used to map collagen deposition across heart tissue sections of a rat model of myocardial infarction, and was compared to conventional staining techniques. Comparison of the size of the collagen scar in heart tissue sections as measured with this methodology and that of trichrome staining showed a strong correlation (R=0.93). A Pearson correlation model between local intensity values in FT-IRIS and immuno-histochemical staining of collagen type I also showed a strong correlation (R=0.86). We demonstrate that FT-IRIS methodology can be utilized to visualize cardiac collagen deposition. In addition, given that vibrational spectroscopic data on proteins reflect molecular features, it also has the potential to provide additional information about the molecular structure of cardiac extracellular matrix proteins and their alterations.
authors.affiliation: Temple University, Department of Mechanical Engineering, Philadelphia, PA, USA.
authors.forename: Rabee
authors.initials: R
authors.lastname: Cheheltani
authors.forename: Jenna M
authors.initials: JM
authors.lastname: Rosano
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.forename: Abdel Karim
authors.initials: AK
authors.lastname: Sabri
authors.forename: Nancy
authors.initials: N
authors.lastname: Pleshko
authors.forename: Mohammad F
authors.initials: MF
authors.lastname: Kiani
mesh_terms: D000465:Algorithms; D000818:Animals; D015415:Biomarkers / Q000032:analysis; D003094:Collagen / Q000032:analysis*; D008297:Male; D009203:Myocardial Infarction / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*
chemical_list: D015415:Biomarkers; D003094:Collagen