BE(2)-M17

The BE (2)-M17 Cell Line has a Better Dopaminergic Phenotype than the Traditionally Used for Parkinson´S Research SH-SY5Y, which is Mostly Serotonergic

SH-SY5Y, the most frequently used in vitro PD model, does not differentiate into a dopaminergic phenotype and mainly exhibits a serotonergic identity after differentiation. In this study, Caravjal-Oliveros et al. attempted to directly compare the dopaminergic and serotonergic marker profile of undifferentiated and differentiated SH-SY5Y and BE(2)-M17 neuroblastoma cells under the same conditions in order to assess their PD model potential.

Identical differentiation protocols with retinoic acid (RA) or staurosporine (Stau) were used to quantify dopaminergic and serotonergic markers in SH-SY5Y and BE(2)-M17 cells. Treatment with 10 μM RA or Stau (10 and 20 nM) resulted in a complete growth arrest of SH-SY5Y cells, whereas BE (2)-M17 cells were less susceptible. Morphological changes were observed after six days of RA treatment and were more evident at 12 days. Treatment with Stau for six days resembled the morphological state of 12 days of RA treatment. After 12 days of RA treatment or six days of Stau, neurites were thicker and the branch length decreased (Fig. 1). Tyrosine hydroxylase (TH), an enzyme essential for dopamine synthesis, was naturally expressed only in BE (2)-M17 cells. TH in BE (2)-M17 cells was significantly induced by RA after 12 days in culture (not in SH-SY5Y cells). Stau treatment further increased TH levels in BE (2)-M17 cells, which also decreased the induction time to six days. TH expression was only seen in SH-SY5Y cells when treated with 20 nM Stau. In all cases, the TH level was always significantly higher in BE (2)-M17 cells. The TH levels in SH-SY5Y cells after Stau treatment were, at most, at the same level of the initial TH levels of BE (2)-M17 cells (Fig. 2A and C).

Fig. 1. Retinoic acid and staurosporine induce morphological changes consistent with neuronal differentiation in BE (2)-M17 and SH-SY5Y cells (Caravjal-Oliveros A, Uriostegui-Arcos M, et al., 2022).

Fig. 2. Induction of tyrosine hydroxylase and tryptophan hydroxylase determined by western blot of untreated and treated BE (2)-M17 and SH-SY5Y cells (Caravjal-Oliveros A, Uriostegui-Arcos M, et al., 2022).

Protection of LM Compounds Against MPP⁺-Induced Neurotoxicity in BE(2)-M17 Cells

Parkinson's disease is driven by a positive feedback loop of microglial activation, oxidative stress, and neuron-derived neuroinflammation. The study focused on determining whether synthetic coumarin–chalcone hybrids LM-021 and LM-036 serve as dual NLRP1/NLRP3 inhibitors to protect human microglia HMC3 cells and neuroblastoma BE(2)-M17 cells from damage caused by MPP⁺ exposure.

Human BE(2)-M17 cells were exposed to different MPP⁺ concentrations (0–5 mM) for 20 h to study MPP⁺ cytotoxicity. MPP⁺ at 0.62 mM concentration was used for further experiments. BE(2)-M17 cells were treated with retinoic acid on day 1 to induce neuronal differentiation, and on day 5 after the removal of retinoic acid, the cells were pre-treated with LM compounds (1–10 μM) for 8 h and then MPP⁺ was added for 40 h (Fig. 3B). As shown in Figure 3C, LM-016, LM-021, and LM-036 at 10 μM concentration increased the cell viability (from 81 to 95–97%, p = 0.004–0.002) and decreased the LDH release in the cell culture medium (from 302 to 160–121%, p < 0.001). The observation of a decreased production of ROS (from 178 to 142–139%, p = 0.005–0.003) also supports the protective role of LM-016, LM-021, and LM-036 against MPP⁺-mediated neurotoxicity in BE(2)-M17 cells (Fig. 3D).

Fig. 3. Reduction of cytotoxicity and ROS of LM compounds in MPP⁺-treated BE(2)-M17 cells (Lin T, Chiu Y, et al., 2024).