F11

Ascl1-Mediated Enhancement of Gabaergic Neuronal Function in Differentiated F11 Cells under High Glucose Conditions

Gamma-aminobutyric acid (GABA)ergic neurons play a key role in pain modulation within the dorsal root ganglion (DRG), making them critical targets for therapeutic studies. Go et al. utilized F11 cells as an in vitro model to examine GABAergic function under high-glucose conditions mimicking diabetic neuropathy.

After 23 days in differentiation media, F11 cells showed a neuron-like shape, transitioning from undifferentiated (F11) to differentiated (D-F11) state (Fig. 1A and B). This was confirmed by increased expression of neuronal markers MAP and Tuj1, and sensory neuronal genes TRPV1, TRPA1, Piezo1/2, Nav1.7, and Nav1.8 (Fig. 1C). Whole-cell patch-clamp recordings showed D-F11 cells had spontaneous action potentials unlike inactive F11 cells (Fig. 1D). Calcium imaging revealed D-F11 cells had a significant increase in the F340/380 ratio upon 50 mM KCl stimulation, unlike F11 cells with minimal calcium influx (Fig. 1E). These results show D-F11 cells have mature sensory neuron characteristics. To study Ascl1's role in GABAergic differentiation, Ascl1 was overexpressed in D-F11 cells using lentiviral transduction. For high-glucose (HG) conditions, cells were incubated in 45 mM glucose for 24 hours. In HG-D-F11 cells, GABAergic gene expression (GAD65, GAD67, vGAT) was reduced but restored by Ascl1 treatment (Fig. 2A). Pro-inflammatory cytokines (TNF-α, NF-κB, IL-1β, IL-6) were elevated in HG conditions and suppressed by Ascl1. Anti-inflammatory cytokines (IL-4, IL-10) were unchanged in HG-D-F11 cells but upregulated by Ascl1 (Fig. 2B). Pain-related ion channels (TRPV1, TRPA1, Nav1.8) were increased in HG-D-F11 cells, but Ascl1 overexpression reduced their expression, with significant reductions in TRPV1 and Nav1.8 (Fig. 2C). These findings suggest Ascl1 promotes GABAergic gene expression, suppresses inflammation, and modulates pain channel expression under HG conditions.

Enzymatically Polymerized Organic Conductors on Native Lipid Membranes

Conductive polymers, with their ability to conduct ions and electrons and flexible mechanical properties, are ideal for bioelectronic applications. Priyadarshini et al. aim to explore the in situ enzymatic polymerization of water-soluble π-conjugated monomers on native lipid bilayers from the F11 cell line, mimicking mammalian neural membranes, to develop minimally invasive neural electrodes for diagnosing and treating neurological disorders.

Real-time QCM-D was used to study the adsorption of F11 blebs, HRP, and ETE-S with H₂O₂ on the Au/Ti quartz sensor. ETE-S is polymerized by HRP to form PETE-S (Fig. 3). HRP has broad substrate selectivity and can polymerize ETE-S using H₂O₂ as the oxidant. After each adsorption step, a PBS buffer rinse was performed and EIS measurements were recorded. Control measurements were also taken without HRP and H₂O₂. The entire QCM-D process, including F11 bleb bilayer formation, HRP adsorption, ETE-S adsorption, and polymerization, is shown in Figure 4. QCM-D frequency shifts indicate changes in the film's hydrated mass, while dissipation shifts reflect changes in its viscoelastic properties. A frequency drop signifies increased adsorbed mass, and a dissipation rise indicates increased film softness. Lower overtones represent changes in the top-most surface of the adsorbed material.