Development and application of a multiple reaction monitoring method for the simultaneous quantification of sodium channels Nav 1.1, Nav 1.2, and Nav 1.6 in solubilized membrane proteins from stable HEK293 cell lines, rodents, and human brain tissues.

RATIONALE: Nav 1.1, 1.2, and 1.6 are transmembrane proteins acting as voltage-gated sodium channels implicated in various forms of epilepsy. There is a need for knowing their actual concentration in target tissues during drug development. METHODS: Unique peptides for Nav 1.1, Nav 1.2, and Nav 1.6 were selected as quantotropic peptides for each protein and used for their quantification in membranes from stably transfected HEK293 cells and rodent and human brain samples using ultra-high-performance liquid chromatography-electrospray ionization tandem mass spectrometry. RESULTS: Nav 1.1, 1.2, and 1.6 protein expressions in three stably individually transfected HEK293 cell lines were found to be 2.1 ± 0.2, 6.4 ± 1.2, and 4.0 ± 0.6 fmol/µg membrane protein, respectively. In brains, Nav 1.2 showed the highest expression, with approximately three times higher (P < 0.003) in rodents than in humans at 3.05 ± 0.57, with 3.35 ± 0.56 in mouse and rat brains and 1.09 ± 0.27 fmol/µg in human brain. Both Nav 1.1 and 1.6 expressions were much lower in the brains, with approximately 40% less expression in human Nav 1.1 than rodent Nav 1.1 at 0.49 ± 0.1 (mouse), 0.43 ± 0.3 (rat), and 0.28 ± 0.04 (humans); whereas Nav 1.6 had approximately 60% less expression in humans than rodents at 0.27 ± 0.09 (mouse), 0.26 ± 0.06 (rat), and 0.11 ± 0.02 (humans) fmol/µg membrane proteins. CONCLUSIONS: Multiple reaction monitoring was used to quantify sodium channels Nav 1.1, 1.2, and 1.6 expressed in stably transfected HEK293 cells and brain tissues from mice, rats, and humans. We found significant differences in the expression of these channels in mouse, rat, and human brains. Nav expression ranking among the three species was Nav 1.2 ≫ Nav 1.1 > Nav 1.6, with the human brain expressing much lower concentrations overall compared to rodent brain.

Healing Words: Effects of Psychoeducation on Likelihood to Seek and Refer Psychedelic-Assisted Psychotherapy Among BIPOC Individuals.

Psychedelic-assisted psychotherapy (PAP) is gaining renewed interest as a treatment for various mental disorders. However, there has been limited Black, Indigenous, and People of Color (BIPOC) representation in PAP clinical trials, signaling the need for culturally consonant communication about the efficacy and safety of PAP. We randomly assigned 321 BIPOC and 301 non-Hispanic White participants to four different modes of psychoeducation (didactic, visual, narrative, hope-based) and tested effects on likelihood of seeking and referring others to PAP using ANCOVAS. The influences of different psychoeducation components on these likelihoods were also tested using hierarchical regression modeling. Regardless of psychoeducation mode, BIPOC participants were more likely to seek PAP than non-Hispanic White participants after psychoeducation. Further, information on physical safety and success rate of PAP uniquely predicted BIPOC participants' likelihood of seeking and referring others to PAP after psychoeducation. Our findings suggest that once provided psychoeducation, BIPOC participants are receptive to seeking or referring others to PAP. BIPOC participants also appear to prioritize physical safety and rate of success of PAP in these decisions. Stigma against PAP is likely not the primary barrier to recruitment of BIPOC individuals into PAP trials. Instead, researchers should conduct more psychoeducational outreach to diversify future trials.