Non specific scrambled controls

POX-specific siRNAs and non-specific scrambled controls were purchased from Santa Cruz Biotechnology (Texas, USA). Differentiated SH-SY5Y cells (2 × 10⁵ cells/well) grown in 6-well culture plates were transfected with 200 nM of POX-specific siRNAs or scrambled controls using Lipofectamine 3000 (Invitrogen, USA) as per the manufacturer’s protocol. 24 h post-transfection, differentiated cells were treated with cocaine at 100 µM and further incubated for an additional 24 h at 37 °C/5% CO₂, washed with PBS (1X) and harvested by gentle scraping for analyses. Knockdown of POX expression was confirmed by immunoblot analysis.

Prolidase-specific siRNAs and non-specific scrambled controls were purchased from Santa Cruz Biotechnology (Texas, USA). HBMECs (2 × 10⁵ cells/well) grown in 6-well culture plates were transfected with 100–300 pM of Prolidase-specific siRNAs or scrambled controls using Jetprime (Polypus, USA) as per the manufacturer’s protocol. Post transfection, cells were incubated for 36–48 h at 37 °C/5% CO2, washed with PBS (1X) and harvested by gentle scraping for protein isolation. Knock-down of prolidase was confirmed by immunoblot analysis.