Neuron-restrictive silencer factor–mediated downregulation of μ-opioid receptor contributes to the reduced morphine analgesia in bone cancer pain

Abstract

Neuron-restrictive silencer factor–induced downregulation of μ-opioid receptor is involved in the reduction of morphine analgesia in sarcoma-induced bone cancer pain.

Antinociceptive effect of intrathecal injection of miR-9-5p modified mouse bone marrow mesenchymal stem cells on a mouse model of bone cancer pain

“…Twenty-five-to 30-g C3H/HeN adult male mice were used in the present study. The mice housing and maintenance were as described previously [15]. Specifically, the mice were attained from Weitong Lihua Laboratory Animal Technology Co, Ltd., Beijing, China.…”

“…The mouse bone cancer pain model was generated as previously described [15]. Specifically, the NCTC murine sarcoma cells were purchased from American Type Culture Collection, Rockville, MD.…”

“…Behavioral assessment related to pain sensation was as described previously [15]. In the present study, spontaneous flinches were used to assess the ongoing pain and paw withdrawal latency (PWT) was used to assess mechanical allodynia.…”

“…On days 3, 7, 14, and 21 post operation, all mice received the same assessments conducted by the same experimenter who are blinded to the treatment regimen. For spontaneous flinches, the mice were observed for 2 min and a scale as described previously [15] was adopted for scoring flinching behaviors. For PWT, von Frey filaments with a weight range as described in our previous study [15] were used to stimulate the hind paws and every mouse was tested for 5 times per stimulus.…”

“…In vitro, REST regulates MOR expression by directly inhibiting MOR transcription [13,14]. In vivo, it is found that REST can modulate MOR gene expression profile by silencing MOR gene promoter epigenetically [15]. Interestingly, REST is also regulated by a variety of cytokines that are known to trigger pain sensation in different pathological situations [16].…”