Assessment of mitochondrial respiratory capacity using minimally invasive and noninvasive techniques in persons with spinal cord injury

This study explores methods to assess mitochondrial function in people with spinal cord injury (SCI) using less invasive techniques like blood tests (PBMCs) and near-infrared spectroscopy (NIRS). Muscle biopsies, the standard method, are difficult to perform regularly in SCI patients. The research aims to find easier ways to monitor mitochondrial health in this population. The study compares mitochondrial respiration measurements from PBMCs and NIRS with those from muscle biopsies in individuals with SCI. The goal is to determine if these less invasive methods can accurately reflect mitochondrial function in skeletal muscle. The findings suggest that PBMC measurements, particularly for mitochondrial complex IV, correlate well with muscle biopsy results. This indicates PBMCs could be a viable alternative for assessing mitochondrial health in SCI patients. NIRS measurements, however, did not show a significant relationship with muscle biopsy results in this study.

• 1
  A significant positive relationship was observed between PBMC and permeabilized skeletal muscle for mitochondrial complex IV (r = 0.86, P < 0.0001), indicating that PBMC measurements can reflect muscle mitochondrial function for this specific complex.
• 2
  Bland-Altman analysis showed agreement between PBMCs and permeabilized muscle fibers for complex IV (MD = 0.18, LOA = -0.86 to 1.21), further supporting the comparability of these methods.
• 3
  No significant relationships were observed between NIRS mitochondrial capacity and respiration in permeabilized muscle fibers, suggesting that NIRS may not be a reliable method for assessing individual mitochondrial complexes in SCI patients in this study.