No abstract

Nicotine withdrawal (NTW) has been shown to increase pain sensitivity. However, the pathogenesis of NTW-induced hyperalgesia syndrome is unknown. Microglial activation, with increased expression of the P2X4 receptor (P2X4R) and brain-derived neurotrophic factor (BDNF) as important markers, is associated with hyperalgesia; therefore, these markers may represent an unprecedented target to prevent hyperalgesia. In this study, we explored the contributions of spinal microglial P2X4R-BDNF signaling in NTW-induced hyperalgesia. Immunohistochemical analysis showed that spinal microglia were activated and that the P2X4R level was increased and colocalized with ionized calcium-binding adapter molecule 1 in NTW-induced hyperalgesia. Furthermore, we showed that microglial activation with NTW resulted in an increased expression of spinal P2X4R and an elevated release of BDNF. Intrathecal minocycline (a specific inhibitor of microglial activation) reversed thermal hyperalgesia as well as increased the spinal microglial P2X4R and BDNF levels induced by NTW. To the best of our knowledge, the present study provides evidence that spinal microglial P2X4R-BDNF signaling is critical for the development of NTW-induced hyperalgesia.

No abstract

Inosine 5′-monophosphate dehydrogenase (IMPDH) is one of the crucial enzymes in the de novo biosynthesis of guanosine nucleotides. It has served as an attractive target in immunosuppressive, anticancer, antiviral, and antiparasitic therapeutic strategies. In this study, pharmacophore mapping and molecular docking approaches were employed to discover novel Homo sapiens IMPDH (hIMPDH) inhibitors. The Güner-Henry (GH) scoring method was used to evaluate the quality of generated pharmacophore hypotheses. One of the generated pharmacophore hypotheses was found to possess a GH score of 0.67. Ten potential compounds were selected from the ZINC database using a pharmacophore mapping approach and docked into the IMPDH active site. We find two hits (i.e., ZINC02090792 and ZINC00048033) that match well the optimal pharmacophore features used in this investigation, and it is found that they form interactions with key residues of IMPDH. We propose that these two hits are lead compounds for the development of novel hIMPDH inhibitors.

No abstract