Alka Singh1, Suruchi Singh2, Saloni Raj1, Ravindra Kumar Garg3, Abbas Ali Mahdi4, Raja Roy2, and Rajeshwar Nath Srivastava1
1Orthopaedic Surgery, King George's Medical University, Lucknow, India, 2Centre of Biomedical Research, Lucknow, India, 3Neurology, King George's Medical University, Lucknow, India, 4Biochemistry, King George's Medical University, Lucknow, India
Synopsis
It
mainly focuses on
finding significant metabolites in serum using 1H NMR based
spectroscopic methods and to study the variation of concentration of these
metabolites during the recovery of the patient ongoing treatment after surgery.
Significant metabolites, namely,
lactate, glycine, acetone and succinate were identified using statistical
methods (ANOVA along with Mann- Whitney U test) and are found to be elevated
during the time of injury. The levels gradually decrease as the patient
recovers in an average period of six months.This is a prospective case-control preliminary study on recovery of the
patient during acute spinal cord injury.Purpose
Proton
NMR Spectroscopic metabolic profiling has been applied to analyze a variety of
metabolites in serum which may be used for evaluating metabolic biomarkers if
any that could help to determine the
degree of injury, severity and to prognosticate
neurologic recovery in Acute Spinal Cord Injury (ASCI).
Introduction
Acute
Spinal Cord Injury (ASCI) is a devastating disease that it results into temporary or often permanent physical disabilities
resulting into large socio-economic costs on affected family and society. According to WHO 2013 data the incidence of
traumatic SCI ranges from 13 to 53 per million populations.1 In
most developing countries, very little is known about the exact epidemiology of
SCI. In India approx 20,000 new cases per
year are registered and major victims are from poor , illiterate population.2 ASCI start a cascade of pathophysiological reaction resulting in
inflammation, electrolytic shifts and edema.3 Various experiments on untargeted metabolomic
profiling of ASCI in animals strongly indicate that in different metabolic
phases, neuronal signalling, stress, and inflammatory metabolites were altered
with an obvious relationship which can be taken as useful clue for further
human research.
Methods
Spinal
trauma patients having a grading ASIA impairment scale A were enrolled for the study. A
total of 30 subjects were analysed, 10 were healthy controls (group-0) having
no significant pathology. The remaining 20 subjects were cases of ASCI (ASIA impairment scale A) which were operated using Fixation with Stem cell treatment (n=10,
group-1) and Fixation without Stem cell treatment (n=10, group-2). All the
samples (case and control) were collected at the time of admission of the
subject to the hospital and after 6th month follow-up. Ethical
clearance was
approved by the institutional committee. Blood samples were
collected in plain vials and were subjected to centrifugation, the serum was
then collected and stored at -800c until analysed. The spectra for
serum were acquired using 1D single pulse Carr-Purcell-Meiboom-Grill (CPMG)
experiment on BrukerBiospinAvance III 800 MHz NMR spectrometer (BrukerGmBH,
Germany). The spectra were quantified after phase and base line correction, and
an analysed using one way ANOVA along with Mann-Whitney U test was performed in
order to observe the difference between the group 0, 1 & 2 subjects on the
basis of the metabolic perturbation. The p-value of ˂0.05 was considered
statistically significant.
Result
Significant metabolic alterations were
observed among the groups in both injured as well as treated subjects (6th
month follow-up). The representative class of proton MR spectra are shown in
Figures 1 & 2 respectively. Valine was found to be significant in
differentiation of group 1 from group 0. It was found to decrease in subjects
operated with stem cell treatment after 6 month while it remained almost constant
in control group. Other metabolites which were found to be significant in
differentiation were lactate, succinate, glycine and acetone. All these
metabolites were found to be elevated at the time of injury and the levels
decreased according to patient’s recovery in 6 months. However, the levels for
control group were constant during this period (Figure 3).
The Mann-Whitney U test allowed the
differentiation on the basis of just 3 metabolites, namely valine, acetone and
glycine. Valine was significant in differentiating group 1 from healthy
individuals. Acetone & glycine were significant in differentiating group 2
from individuals. Acetone alone was responsible to differentiate the Stem cell treatment
from conservative treatment, and therefore can be considered as a biomarker for
ASCI.
Discussion
Observation of evaluated lactate levels
is common in severely injured subjects and shows a dependency on the severity
of injury and related to neuropsychological deficits. Glycine plays a pivotal
role in development of neuropathic pain and its concentrations and the synoptic
cleft is controlled by the glycine transporters. At the time of injury the
signalling of pain occurs which may be due to elevated glycine levels. These
levels are further observed to decrease as the patients recovers and pain
relievers. This is an ongoing study which has
started to show some promising results. Till now a small number of cases with
only serum samples were analysed and some significant metabolite relationships
with disease progression has been observed.
Conclusion
The
study is being planned further on larger number of cases with increased follow-ups.
Urine and cerebrospinal fluid samples will also be incorporated and compared on
the next stage of this study. This would certainly provide a larger perspective
in relationships between metabolites and progress of spinal cord injury.
Acknowledgements
The
authors are thankful to King George’s Medical University and Centre of Biomedical
Research, SGPGIMS, Lucknow, where the present study was conducted.References
1. Jerome B. et al.
International perspectives on spinal cord injury, World Health Organization publication. Http://apps.who.int/iris/bitstream/10665/94192/10/WHO_NMH_VIP_13.03_rum.pdf2013.
2. Singh R, Sharma SC,
Mittal R, et al. Traumatic spinal cord injuries in Haryana: an epidemiological
study. Indian
J Community Med. 2003; 28:184-186.
3. Fujieda Y, et al., Metabolite
Profiles Correlate Closely with Neurobehavioral Function in Experimental Spinal
Cord Injury in Rats. PLOS ONE. 2012; 7: e43152.