Diabetic neuropathic pain (DNP) is a troublesome diabetes complication all over the world. P2X3 receptor (P2X3R), a purinergic receptor from dorsal root ganglion (DRG), has important roles in neuropathic pain pathology and nociceptive sensations. Here, we investigated the involvement of DRG P2X3R and the effect of 2 Hz electroacupuncture (EA) on DNP. We monitored the rats’ body weight, fasting blood glucose level, paw withdrawal thresholds, and paw withdrawal latency, and evaluated P2X3R expression in DRG. We found that P2X3R expression is upregulated on DNP, while 2 Hz EA is analgesic against DNP and suppresses P2X3R expression in DRG. To evaluate P2X3R involvement in pain modulation, we then treated the animals with A317491, a P2X3R specific antagonist, or α β-me ATP, a P2X3R agonist. We found that A317491 alleviates hyperalgesia, while α β-me ATP blocks EA’s analgesic effects. Our findings indicated that 2 Hz EA alleviates DNP, possibly by suppressing P2X3R upregulation in DRG.

Pyoluteorin is a natural occurring antibiotic and its anti-tumor activity has rarely been reported. This study aims to investigate the anti-tumor effects of pyoluteorin on human non-small cell lung cancer (NSCLC) cells. The cell proliferation was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was determined through caspase3 activity assay and immunoblotting. Autophagy was measured by transmission electron microscope (TEM) and immunostaining. The autophagy-related proteins were detected through immunoblotting. We found that pyoluteorin showed significant anti-tumor effects on human NSCLC cell lines H1299 (IC 50 1.57 µM) and H2030 (IC 50 1.94 µM). Moreover, pyoluteorin could induce apoptosis and autophagy as evidence by the upregulation of caspase3 activity, the accumulation of LC3 and expression of apoptosis or autophagy related proteins. In addition, pyoluteorin induced autophagy through c-Jun N-terminal kinase/B-cell lymphoma-2 (JNK/Bcl-2) signal pathway. Blocking JNK/Bcl-2 pathway significantly attenuated pyoluteorin-induced autophagy. Moreover, inhibition of autophagy by 3-methyladenine (3-MA) or Beclin1 knockout greatly promoted pyoluteorin-induced apoptosis and cell death. Our results showed that pyoluteorin could induce both apoptosis and autophagy in human NSCLC cells. Combination of pyoluteorin with autophagy inhibitior significantly promoted pyoluteorin-induced apoptosis and may be a potential anticancer strategy in the NSCLC therapy.

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Diabetic neuropathic pain (DNP) is frequent among patients with diabetes. We previously showed that P2X3 upregulation in dorsal root ganglia (DRG) plays a role in streptozotocin (STZ)-induced DNP but the underlying mechanism is unclear. Here, a rat model of DNP was established by a single injection of STZ (65 mg/kg). Fasting blood glucose was significantly elevated from the 1st to 3rd week. Paw withdrawal thresholds (PWTs) and paw withdrawal latencies (PWLs) in diabetic rats significantly reduced from the 2nd to 3rd week. Western blot analysis revealed that elevated p-CaMKIIα levels in the DRG of DNP rats were accompanied by pain-associated behaviors while CaMKIIα levels were unchanged. Immunofluorescence revealed significant increase in the proportion of p-CaMKIIα immune positive DRG neurons (stained with NeuN) in the 2nd and 3rd week and p-CaMKIIα was co-expressed with P2X3 in DNP rats. KN93, a CaMKII antagonist, significantly reduce mechanical hyperalgesia and thermal hyperalgesia and these effects varied dose-dependently, and suppressed p-CaMKIIα and P2X3 upregulation in the DRGs of DNP rats. These results revealed that the p-CaMKIIα upregulation in DRG is involved in DNP, which possibly mediated P2X3 upregulation, indicating CaMKIIα may be an effective pharmacological target for DNP management.

The RAS protein activator like 2 (Rasal2) has been reported to be a tumor suppressor in variety of cancers; while an oncogenic protein in ovarian cancer and triple negative breast cancer (TNBC). However, the exact role of Rasal2 in non-small cell lung cancer (NSCLC) is lacking. This study aimed to investigate the role of Rasal2 in NSCLC and the underlying mechanisms. Rasal2 expression level was measured in NSCLC tissue and cells by using quantitative (q)-PCR and immunoblotting analysis. The clinical implication of Rasal2 in NSCLC patients was also analyzed. The function role of Rasal2 in NSCLC cells were measured by small interfering RNA (si-RNA), immunostaining, transwell assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Low Rasal2 expression level was observed in human NSCLC tissue and cell lines and significantly related to tumor thickness, ulceration and TNM staging in NSCLC patients. Rasal2 knockdown significantly increased NSCLC cell invasion and migration. Mechanistically, we showed that Rasal2 knockdown significantly increased the phosphorylation level of extracellular signal-regulated kinase (ERK)/Raf1/mitogen-activated protein extracellular kinase (MEK) thus activated Ras/ERK signal pathway. Thus, our data showed that Rasal2 is downregulated in NSCLC cells and act as an epithelial-mesenchymal transition (EMT) and metastasis suppressor through the Ras/ERK pathway. Rasal2 may be a prognostic biomarker for NSCLC in the future.