Reproducibility of total choline/water ratios in mouse U87MG xenograft tumors by 1H-MRS

1H-MRS Quantitation of Age-Dependent Taurine Changes in Mouse Brain

PURPOSE

A mouse model of Alzheimer's disease demonstrates reduced beta-amyloid levels in the whole brain, associated with a gain of hippocampal memory, after drinking taurine-enriched water; this suggests that a taurine supplement could be a promising treatment for cognitive deficit. The objective of this study is to establish a methodology for quantifying taurine in the whole brain, taking advantage of the rapid development of non-invasive imaging techniques such as magnetic resonance imaging and magnetic resonance spectroscopy (MRS).

PROCEDURES

Single-voxel proton MRS was used to obtain quantifiable taurine peaks at 3.25 and 3.43 ppm. Quantitative MRS results were obtained in C57BL/6 mice of various age groups: 4, 11, 18, and 27 months old.

RESULTS

Compared with the 4-month-old group, taurine levels dropped significantly only at 27 months of age (p = 0.03). However, a significant decrease of N-acetyl-aspartate (NAA) in the brain was observed at both 18 and 27 months (p = 0.03 and p = 0.02). In addition, MRS-measured taurine level is highly correlated with hippocampal volume (r = 0.95).

CONCLUSIONS

These results suggest that decreased taurine levels in the brain could be used as biomarkers for hippocampal changes and are fully translatable into putative cognitive loss in both animal models and human studies without the ex vivo approach.

Evaluation of short- and long-term efficacy of chemoradiotherapy for advanced cervical cancer using HSP70 protein combined with multimodal MRI

This study aims to evaluate the efficacy of chemoradiotherapy for advanced cervical cancer using heat shock protein 70 (HSP70) combined with multimodal MRI. The protein expressions of HSP70 in biopsy specimens obtained from 101 patients with cervical cancer were detected by immunohistochemistry. Plain MRI scan, DWI, DCE-MR, and MRS were performed before and after a period of 6 months of chemoradiotherapy. All patients were assigned into the complete response (CR) and partial response (PR) groups. HSP70 protein expression, tumor diameter, and tumor volume were lower in the CR group than in the PR group. The rate of tumor shrinkage, relative positive enhancement integral (rPEI), relative maximum slope of decrease (rMSD), relative signal enhancement ratio at 60 s (rSER₆₀ ) and maximum SER (rSER_max ), mean apparent diffusion coefficient (ADC_mean ) and minimum ADC value (ADC_min ) values in the CR group were higher than those in the PR group. Tumor diameter and volume, rSER₁₅ and rSER₃₀ were reduced after chemoradiotherapy, while rMSD, rSER_max , time to peak (TTP), ADC_mean and ADC_min were higher after the treatment. The receiver operating characteristic (ROC) curves indicated that HSP70 expression, tumor diameter, rPEI, ADC_mean and Cho peak showed the better chemoradiotherapy efficacy. Our data demonstrates that HSP70 protein combined with multimodal MRI may accurately evaluate the chemoradiotherapy efficacy of patients with advanced cervical cancer. The recurrence of cervical cancer significantly decreased in patients with negative expression of HSP70 and HSP70 protein detection provides potential therapy for the prevention, diagnosis, and prognosis of cervical cancer.