Electroacupuncture alleviates streptozotocin-induced diabetic neuropathic pain via suppressing phosphorylated CaMKIIα in rats.

Diabetic neuropathic pain (DNP) is a frequent complication of diabetes. Calcium/calmodulin-dependent protein kinase II α (CaMKIIα), a multi-functional serine/threonine kinase subunit, is mainly located in the surface layer of the spinal cord dorsal horn (SCDH) and the primary sensory neurons in dorsal root ganglion (DRG). Numerous studies have indicated electroacupuncture (EA) takes effect in various kinds of pain. In this research, we explored whether CaMKIIα on rats' SCDH and DRG participated in DNP and further explored the mechanisms underlying the analgesic effects of EA. The DNP model in rats was successfully established by intraperitoneal injection of streptozotocin. Certain DNP rats were treated with intrathecal injections of KN93, a CaMKII antagonist, and some of the DNP rats received EA intervention. The general conditions, behaviors, the expressions of CaMKIIα and phosphorylated CaMKIIα (p-CaMKIIα) were evaluated. DNP rats' paw withdrawal threshold was reduced and the expressions of p-CaMKIIα in SCDH and DRG were upregulated compared with the Normal group, while the level of CaMKIIα showed no significance. KN93 attenuated DNP rats' hyperalgesia and reduced the expressions of p-CaMKIIα. We also found EA attenuated the hyperalgesia of DNP rats and reduced the expressions of p-CaMKIIα. The above findings suggest that p-CaMKIIα in SCDH and DRG is involved in DNP. The analgesic effect of EA in DNP might be related to the downregulation of p-CaMKIIα expression level. Our study further supports that EA can be an effective clinical treatment for DNP.

Electroacupuncture may alleviate diabetic neuropathic pain by inhibiting the microglia P2X4R and neuroinflammation.

Diabetic neuropathic pain (DNP) is a common and destructive complication of diabetes mellitus. The discovery of effective therapeutic methods for DNP is vitally imperative because of the lack of effective treatments. Although 2 Hz electroacupuncture (EA) was a successful approach for relieving DNP, the mechanism underlying the effect of EA on DNP is still poorly understood. Here, we established a rat model of DNP that was induced by streptozotocin (STZ) injection. P2X4R was upregulated in the spinal cord after STZ-injection. The upregulation of P2X4R was mainly expressed on activated microglia. Intrathecal injection of a P2X4R antagonist or microglia inhibitor attenuated STZ-induced nociceptive thermal hyperalgesia and reduced the overexpression of brain-derived neurotrophic factor (BDNF), interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) in the spinal cord. We also assessed the effects of EA treatment on the pain hypersensitivities of DNP rats, and further investigated the possible mechanism underlying the analgesic effect of EA. EA relieved the hyperalgesia of DNP. In terms of mechanism, EA reduced the upregulation of P2X4R on activated microglia and decreased BDNF, IL-1ß and TNF-α in the spinal cord. Mechanistic research of EA's analgesic impact would be beneficial in ensuring its prospective therapeutic effect on DNP as well as in extending EA's applicability.

Inhibition of phosphorylated calcium/calmodulin-dependent protein kinase IIα relieves streptozotocin-induced diabetic neuropathic pain through regulation of P2X3 receptor in dorsal root ganglia.

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.

Dorsal root ganglia P2X4 and P2X7 receptors contribute to diabetes-induced hyperalgesia and the downregulation of electroacupuncture on P2X4 and P2X7.

Diabetic neuropathic pain (DNP) is highly common in diabetes patients. P2X receptors play critical roles in pain sensitization. We previously showed that elevated P2X3 expression in dorsal root ganglion (DRG) contributes to DNP. However, the role of other P2X receptors in DNP is unclear. Here, we established the DNP model using a single high-dose streptozotocin (STZ) injection and investigated the expression of P2X genes in the DRG. Our data revealed elevated P2X2, P2X4, and P2X7 mRNA levels in DRG of DNP rats. The protein levels of P2X4 and P2X7 in DNP rats increased, but the P2X2 did not change significantly. To study the role of P2X4 and P2X7 in diabetes-induced hyperalgesia, we treated the DNP rats with TNP-ATP (2',3'-O-(2,4,6-trinitrophenyl)-adenosine 5'-triphosphate), a nonspecific P2X1-7 antagonist, and found that TNP-ATP alleviated thermal hyperalgesia in DNP rats. 2 Hz electroacupuncture is analgesic against DNP and could downregulate P2X4 and P2X7 expression in DRG. Our findings indicate that P2X4 and P2X7 in L4-L6 DRGs contribute to diabetes-induced hyperalgesia, and that EA reduces thermal hyperalgesia and the expression of P2X4 and P2X7.

Circulating THBS1: A Risk Factor for Nonalcoholic Fatty Liver Disease in Obese Children.

INTRODUCTION: Thrombospondin 1 (THBS1) is a highly expressed adipokine in adults with obesity. In the present study, we aimed to investigate the clinical significance of THBS1in children with obesity and nonalcoholic fatty liver disease (NAFLD) and determine the effect of metformin on THBS1 expression in dietary-induced obese (DIO) mice. METHODS: A cross-sectional study was conducted among 78 obese children and 35 nonobese children. Anthropometric parameters, clinical data, and circulating THBS1 levels were measured. The expression of THBS1 was detected in the serum and liver tissue from diet-induced obese mice (C57BL/6) with or without metformin treatment. RESULTS: Higher THBS1 levels were observed in children with NAFLD and higher SDS-BMI. Individuals in the higher THBS1 quartile had a higher prevalence of hypo-high-density lipoprotein cholesterol (HDL-C). Logistic regression analysis showed a significant correlation between THBS1 and NAFLD, as well as between hip circumference and leptin levels. Receiver-operating characteristic (ROC) analysis revealed that THBS1 was a more sensitive predictor of NAFLD than leptin. Additionally, metformin ameliorated hepatic steatosis and decreased hepatic THBS1 expression in high-fat diet (HFD)-fed mice. CONCLUSIONS: Circulating THBS1 level may be a risk factor for NAFLD in obese children. Our findings provided a novel approach of metformin administration for the prevention and treatment of NAFLD. This study also confirmed that metformin decreased the expression of hepatic THBS in DIO mice.

[Effect of electroacupuncture and pretreatment of electroacupuncture on pain sensitization and expression of P2X7R in spinal dorsal horn in rats with diabetic neuropathic pain].

OBJECTIVE: To observe the occurrence time of neuralgia and the expression of purinergic ligand-gated ion channel 7 receptor (P2X7R) in the dorsal horn of the spinal cord after intraperitoneal injection of streptozotocin (STZ) in diabetic rats, and to explore the effect of electroacupuncture (EA) and pretreatment of EA on the heat pain threshold and expression of P2X7R in the spinal dorsal horn in rats with diabetic neuropathic pain (DNP), and to explore the possible mechanism of EA for DNP. METHODS: PartⅠ: Thirty male SD rats were randomly selected from 64 male SD rats as the control group; the remaining rats were given intraperitoneal injection of STZ (10 mg/mL) at a dose of 65 mg/kg to establish the diabetes model, and 30 rats were successfully modeled as the model group. The control group and the model group were divided into three subgroups respectively at 7, 14 and 21 days, with 10 rats in each subgroup. Body mass, fasting blood glucose (FBG) and thermal pain threshold were recorded at 7, 14 and 21 days after injection; the expression of P2X7R in spinal dorsal horn was detected by Western blot. PartⅡ: Eight SD rats were randomly selected from 35 male SD rats as the blank group, and the remaining 27 rats were given intraperitoneal injection of STZ (10 mg/mL) at a dose of 65 mg/kg to establish the diabetes model. The 24 rats with successful diabetes model were randomly divided into a DNP group, an EA group and a pre-EA group, 8 rats in each group. Fifteen to 21 days after STZ injection, the EA group received EA at "Zusanli" (ST 36) and "Kunlun" (BL 60), continuous wave, frequency of 2 Hz, 30 min each time, once a day; the intervention method in the pre-EA group was the same as that in the EA group. The intervention time was 8 to 14 days after STZ injection. The body mass, FBG and thermal pain threshold were recorded before STZ injection and 7, 14 and 21 days after STZ injection; the expression of P2X7R in spinal dorsal horn was detected by Western blot 21 days after injection. RESULTS: PartⅠ: Compared with the control group, in the model group, the body mass was decreased and FBG was increased 7, 14 and 21 days after STZ injection (P<0.01), and the thermal pain threshold was decreased 14 and 21 days after STZ injection (P<0.05), and the expression of P2X7R in spinal dorsal horn was increased 7, 14 and 21 days after STZ injection (P<0.05, P<0.01). PartⅡ: Compared with the blank group, in the DNP group, the body mass was decreased and fasting blood glucose were increased 7, 14 and 21 days after STZ injection (P<0.01). Compared with the DNP group, in the pre-EA group, the heat pain threshold was increased 14 and 21 days after STZ injection (P<0.05), while in the EA group, the heat pain threshold was increased 21 days after STZ injection (P<0.01), and the expression of P2X7R in the dorsal horn in the EA group and the pre-EA group was decreased (P<0.01). CONCLUSION: The diabetic neuropathic pain is observed 14 days after STZ injection. EA could not only treat but also prevent the occurrence of DNP, and its mechanism may be related to down-regulation of P2X7R expression in the dorsal horn of the spinal cord.

Increased asprosin is associated with non-alcoholic fatty liver disease in children with obesity.

BACKGROUND: Obesity is a common disease among children, often accompanied by a lot of metabolic disease. Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of obesity among children and adolescents. Asprosin has been identified as a new adipokine that is closely associated with hepatic glucose metabolism. However, few data on asprosin in obese children with NAFLD are available. The present study focuses on the relationship between serum asprosin level and NAFLD in children with obesity. METHODS: A total of 110 subjects (71 boys and 39 girls aged 6-18 years) were recruited from the Second Affiliated Hospital of Xi'an Jiaotong University: 36 obese children with NAFLD, 39 obese children without NAFLD and 35 lean controls. Anthropometric parameters and biochemical data were measured, and the concentrations of asprosin were detected by ELISA. RESULTS: The levels of serum asprosin were significantly higher in obese children, particularly those with NAFLD and were positively correlated with body mass index, waist to height ratio, fasting blood glucose, alanine aminotransferase and tumor necrosis factor-alpha. Furthermore, asprosin was independently associated with NAFLD in binary logistic regression analysis. CONCLUSION: Serum asprosin levels were elevated in obese children, especially in those with NAFLD, and were involved in the pathogenesis of NAFLD in children with obesity.

miR­29a suppresses IL­13­induced cell invasion by inhibiting YY1 in the AKT pathway in lung adenocarcinoma A549 cells.

IL­13 is a proinflammatory cytokine associated with multiple pathological conditions and the promotion of metastasis in lung cancer. Previous studies have demonstrated that IL­13 and YY1 are associated with PI3K/AKT signaling. In addition, miR­29a has been found to play a critical role in cell invasion in lung cancer. However, the molecular mechanism of miR­29a underlying its involvement in IL­13­induced lung cancer cell invasion remains largely unknown. In the present study, we aimed to investigate the role of miR­29a in cell invasion mediated by IL­13 in lung cancer. By using MTT and wound­scratch assays, we assessed cell proliferation and migration induced by IL­13, and identified activation of the PI3K/AKT/YY1 pathway. Inhibition of PI3K/AKT by LY294002 downregulated IL­13­induced YY1 expression. Furthermore, we found that miR­29a directly targets YY1 and suppressed its expression in lung cancer. By using MTT, flow cytometry and Transwell assays, overexpression of miR­29a restricted both YY1 and N­cadherin expression, and inhibited IL­13­induced invasion of lung cancer A549 cells. Taken together, these findings demonstrate that PI3K/AKT/YY1 is involved in the regulation of lung cancer cell behavior induced by IL­13, and miR­29a represents a promising therapeutic target.