Details

Autor(en) / Beteiligte

• Shah, Prithvi K
• Ye, Fan
• Liu, Min
• Jayaraman, Arun
• Baligand, Celine
• Walter, Glenn
• Vandenborne, Krista

Titel

In vivo ^sup 31^P NMR spectroscopy assessment of skeletal muscle bioenergetics after spinal cord contusion in rats

Ist Teil von

• European journal of applied physiology, 2014-04, Vol.114 (4), p.847

Ort / Verlag

Heidelberg: Springer Nature B.V

Erscheinungsjahr

2014

Quelle

Springer journals

Beschreibungen/Notizen

• Muscle paralysis after spinal cord injury leads to muscle atrophy, enhanced muscle fatigue, and increased energy demands for functional activities. Phosphorus magnetic resonance spectroscopy (^sup 31^P-MRS) offers a unique non-invasive alternative of measuring energy metabolism in skeletal muscle and is especially suitable for longitudinal investigations. We determined the impact of spinal cord contusion on in vivo muscle bioenergetics of the rat hind limb muscle using ^sup 31^P-MRS. A moderate spinal cord contusion injury (cSCI) was induced at the T8-T10 thoracic spinal segments. ^sup 31^P-MRS measurements were performed weekly in the rat hind limb muscles for 3 weeks. Spectra were acquired in a Bruker 11 T/470 MHz spectrometer using a 31P surface coil. The sciatic nerve was electrically stimulated by subcutaneous needle electrodes. Spectra were acquired at rest (5 min), during stimulation (6 min), and recovery (20 min). Phosphocreatine (PCr) depletion rates and the pseudo first-order rate constant for PCr recovery (k ^sub PCr^) were determined. The maximal rate of PCr resynthesis, the in vivo maximum oxidative capacity (V ^sub max^) and oxidative adenosine triphosphate (ATP) synthesis rate (Q ^sub max^) were subsequently calculated. One week after cSCI, there was a decline in the resting total creatine of the paralyzed muscle. There was a significant reduction (~24 %) in k ^sub PCr^ measures of the paralyzed muscle, maximum in vivo mitochondrial capacity (V ^sub max^) and the maximum oxidative ATP synthesis rate (Q ^sub max^) at 1 week post-cSCI. During exercise, the PCr depletion rates in the paralyzed muscle one week after injury were rapid and to a greater extent than in a healthy muscle. Using in vivo MRS assessments, we reveal an acute oxidative metabolic defect in the paralyzed hind limb muscle. These altered muscle bioenergetics might contribute to the host of motor dysfunctions seen after cSCI.[PUBLICATION ABSTRACT]