Preliminary evidence for white matter metabolite differences in marijuana-dependent young men using 2D J-resolved magnetic resonance spectroscopic imaging at 4 Tesla

Abstract

Chronic marijuana (MRJ) use is associated with altered cognition and mood state, altered brain metabolites, functional and structural brain changes. The objective of this study was to apply proton magnetic resonance spectroscopic imaging (MRSI) to compare proton metabolite levels in 15 young men with MRJ-dependence and 11 healthy non-using (NU) young men. Spectra were acquired at 4.0 Tesla using 2D J-resolved MRSI to resolve coupled resonances in J-space and to quantify the entire J-coupled spectral surface of metabolites from voxels containing basal ganglia and thalamus, temporal and parietal lobe, and occipital white and gray matter. This method permitted investigation of high-quality spectra for regression analyses to examine metabolites relative to tissue type. Distribution of myo-inositol (mI)/creatine (Cr) was altered in the MRJ group whereas the NU group exhibited higher mI/Cr in WM than GM, this pattern was not observed in MRJ subjects. Significant relationships observed between global mI/Cr and distribution in WM, and self-reported impulsivity and mood symptoms were also unique between MRJ and NU groups. These preliminary findings suggest that mI, and distribution of this glial metabolite in WM, is altered by MRJ use and is associated with behavioral and affective features reported by young MRJ-dependent men.

Imaging Biomarkers of the Neuroimmune System among Substance Use Disorders: A Systematic Review

“…Five MRS studies met our inclusion criteria (Table 2) [167-171]. Four studies reported lower myo- inositol and myo- inositol/creatine ratio levels (10–36%) among regular cannabis users relative to controls [168-171].…”

“…Four studies reported lower myo- inositol and myo- inositol/creatine ratio levels (10–36%) among regular cannabis users relative to controls [168-171]. In each study, subjects were not required to remain cannabis-abstinent prior to imaging [168-171].…”

“…Finally, sex effects may exist [167]. The majority of MRS studies conducted to date were underpowered to explore possible sex effects [168-171]; thus, future research is needed to investigate this possibility.…”

Marijuana’s Role in The Adolescent Population

“…Studies utilizing magnetic resonance spectroscopy showed alterations in glutamate, Nacetyl aspartate, creatinine and myo-nositol in the anterior cingulate [53]. Also, myo-inositol/creatine ratios were demonstrated in subcortical area as well as a reduction of myo-inositol in the white matter [52].…”

“…Through the cannabinoid receptors, Marijuana causes changes in inhibitory as well as exitatory neuro-transmitter release. In particular alterations in dopamine, glutamate and GABA release have been shown [52]. Studies utilizing magnetic resonance spectroscopy showed alterations in glutamate, Nacetyl aspartate, creatinine and myo-nositol in the anterior cingulate [53].…”