Raman spectral characteristics of neck and head of femur in low-density lipoprotein receptor gene knockout mice submitted to treadmill aerobic training.

Hypercholesterolemia is associated with deterioration of bone tissue. Trough Raman spectroscopy, the present study aimed to assess the molecular changes in terms of mineral and organic bone-tissue remodeling in low-density lipoprotein receptor gene knockout mice (LDLr-/-) submitted to treadmill aerobic training. In order to evaluate alterations in trabecular bone and cartilage surface, neck and head femoral were assessed into four groups: (CON, n=7), the 1) animals did not perform any physical activity and had hypercholesterolemia (CON, n=7); The trained groups where animals underwent a protocols of low, moderate and high training for 8weeks and 4 times per week on a treadmill with progressive intensities: running speed (8-13m/min) and time of exercise (20-60min). These progressive intensities were needed to adjust the working load for the physical training to 2) 30-49% (LOW, n=7), 3) 50-79% (MOD, n=7), and 4) 80-100% (HIGH, n=7) of the maximum running speed. Each group was examined for molecular changes in both bone phases (mineral and organic) using principal components analysis (PCA). All exercised groups showed a significant increase (p<0.05) of bone remodeling in trabecular area and a higher content of proteins (organic content) in cartilage independently of physical activity intensity. Thus, this work demonstrated that physical training could act as a bone-protector factor in hyperlipidemic animal model as well as Raman technique associated with PCA analysis may be feasible methodology for assessment or monitoring of bone at the molecular level.

Detection of creatine in rat muscle by FTIR spectroscopy.

There is a current lack of clarity regarding the use of Fourier-transform infrared spectroscopy (FT-IR) to evaluate intramuscular concentrations of creatine (Cr). Thus, the aim of this study was to assess the FT-IR spectral features of tibialis anterior muscle in rats submitted in conditions that were expected to perturb the Cr pool. First, an experiment was performed to ensure that FT-IR was able to detect the Cr intramuscular in sedentary and supplemented rats (Experiment 1). The effect of physical exercise on spectral muscle features was then examined, especially in relation to the spectroscopy markers (Experiment 2). Using pure Cr (control), it was possible to verify that only the peaks centered at 1308 and 1396 cm(-1) of all the spectra showed the same peak positions, indicating these FT-IR shifts as indirect markers of Cr intramuscular content. Experiment 2 revealed a higher Cr content for the Cr-supplemented and exercised animals than the rats of other groups. In conclusion, it was demonstrated that FT-IR spectroscopy using 1396 cm(-1) and mainly 1308 band was able to monitor Cr muscle content in rats sedentary, Cr-supplemented, and submitted to physical training. Besides, FT-IR could be a feasible method for the nondestructive assessment of Cr skeletal muscle content.