Objective:To investigate the effects of myeloid-derived growth factor(MYDGF) on inflammatory response and osteoclast differentiation of RAW264.7 cells.Methods:The RAW264.7 osteoclast precursor cells were cultured and treated with different concentrations of recombinant MYDGF protein(rMYDGF), and their cell viability was assessed using the MTT assay. RAW264.7 cells were induced with lipopolysaccharide(LPS) to induce inflammation, and the expression of inflammatory mediators and cell polarization were observed after intervention with rMYDGF. The RAW264.7 cells were induced for osteoclast differentiation using receptor activator of nuclear factor-κB ligand(RANKL), and rMYDGF was added for intervention. Osteoclast differentiation was evaluated by tartrate-resistant acid phosphatase(TRAP) staining. The osteoclast resorption pits and the number of actin rings(F-actin rings) were observed under a microscope. Reverse transcription PCR was performed to detect the expression of activated T cell nuclear factor 1(Nfatc1), cathepsin K(CTSK), and c-Fos genes during osteoclast differentiation. The protein phosphorylation levels of nuclear factor-κB(NF-κB) signaling pathway proteins were detected using Western blotting.Results:MTT assay showed that rMYDGF did not significantly inhibit the viability of RAW264.7 cell when the concentration was lower than 100 ng/mL. Moreover, rMYDGF inhibited the expression levels of inflammatory factors and M1 cell polarization after LPS stimulation. Compared with the control group, the number and area of TRAP positive cells, the number and area of bone resorption pit were decreased in rMYDGF intervention group respectively, as well as the area of the F-actin ring was reduced and its shape was incomplete after rMYDGF intervention. Furthermore, rMYDGF reduced the expression levels of osteoclast-specific marker genes and inhibited the phosphorylation of NF-κB signaling pathway protein IκBα during osteoclast differentiation.Conclusion:MYDGF inhibits the inflammatory response and osteoclast differentiation of RAW264.7 cells.

Objective To investigate the effect of myeloid-derived growth factor ( MYDGF) on the secretion of glucagon-like peptide 1 ( GLP-1) in type 2 diabetic mice and its mechanism. Methods A type 2 diabetes model was established by injecting streptozotocin into C57BL/6J wild type ( WT) mice and MYDGF knockout ( KO) mice, which were divided into diabetic group ( WT-D, KO-D) and non-diabetic group ( WT-ND, KO-ND) . Six weeks later, the relevant indicators were detected. Next, those mice were divided into wild-type diabetes group (WT-GFP), wild-type diabetes MYDGF intervention group (WT-MYDGF), knockout type diabetes group (KO-GFP), and knockout type MYDGF intervention group ( KO-MYDG ) according to whether or not the AAV-MYDGF intervention was performed. The wild-type non-diabetic mice were used as a blank control group to observe the effects of MYDGF on biochemical indexes, GLP-1 secretion, and mitogen-activated protein kinase kinase ( MEK)/extracellular regulated protein kinases ( ERK) signal pathway in mice. Results After 6 weeks of intervention, there was no significant difference in the glucose and lipid metabolism indexes between WT-ND and KO-ND groups ( P>0.05) . Compared with WT-D group, fasting plasma glucose (FPG), HbA1C, and blood lipid levels in KO-D group were increased, while gcg, pc3 mRNA, and GLP-1 secretion levels were decreased (all P<0.05). Compared with the WT-GFP group, FPG, HbA1C , and blood lipid levels were decreased in WT-MYDGF group, while gcg and pc3 mRNA, and GLP-1 secretion levels were increased (all P<0.05). KO group revealed a result similar to that in WT group after MYDGF intervention. Western blotting showed that the phosphorylation level of ERK1/2 was lowered in KO diabetic mice compared with WT diabetic mice, which was enhanced in WT and KO mice after MYDGF intervention. Conclusions MYDGF promotes the secretion of GLP-1 by activating MEK/ERK signaling pathway, thereby delaying the development of diabetes.

Objective To investigate the effects of growth differentiation factor 11 ( GDF11 ) on β-cell function in db/db mice and its possible mechanism. Methods Twenty eight-week-old male db/db mice were randomizedtoi.p. administration of GDF11(0.3mg·kg-1·day-1)or equivalent PBS(n=10)for 6 weeks.10age-matched male db/m were used as normal control, received equivalent PBS injection for 6 weeks. Blood glucose levels, body weights and food intake were monitored weekly. IPGTT and glucose-stimulated insulin secretion ( GSIS) were analyzed. After 6 weeks of intervention, serum HbA1C , TG, TC, and FFA were measured respectively. The concentrations of hormones in serum and pancreas were evaluated. The mRNA expression of Pdx-1, MafA, Nkx6. 1, and insulin2 were determined by RT-PCR. The expression of phosphorylated Smd2 (P-Smad2), Smad2 in islet were examined by western blot. Results Compared with NC group, GDF11 administration decreased FBG, HbA1C , modified lipid profiles. GDF11 improved glucose tolerance and augmented GSIS. Moreover, GDF11 increased serum insulin and pancreatic insulin content, while decreased serum glucagon concentration. The expression of Pdx-1, MafA, Nkx6. 1, and Insulin2 were significantly increased in GDF11 group. GDF11 elevated the expression of P-Smad2 in islets. Conclusion s GDF11 may preserve β-cell function and facilitate the secretion and production of insulin. Diminishing the metabolic abnormalities, alleviating the secretion of glucagon, as well as maintaining the key transcript factor activation may contribute to the amelioration of β-cell function after GDF11 administration. Smad2 pathway may be related to the protective effects of GDF11.

Objective To investigate the effects and possible mechanism of growth differentiation factor 11 (GDF11)on angiogenesis in diabetic hindlimb ischemia. Methods Sixty SD rats were used in this study. Diabetes was induced by intraperitoneal injection of streptozotocin. 3 days after streptozotocin administration, 40 rats with plasma glucose concentration≥16.7 mmol/L were selected in the subsequent experiments. 12 weeks after diabetes was induced,the left femoral artery and all the sides branches were dissected free and excised. After resection of the left femoral artery,rats were randomized to four groups:PBS group(n=10),GDF11 group(n=10),IgG Ab group (n=10),or GDF11 Ab group(n=10). After 0,7,and 14 days,the serial blood flows were measured by a Laser Doppler perfusion image(LDPI)analyzer. To detect capillary endothelial cell,the sections of muscles were reacted with anti-CD31 monoclonal antibodies,and subsequently reacted with Cy3-conjugated anti-rabbit IgG antibody. The expression levels of HIF1α and VEGF were detected by western blotting. Results In GDF11 group significantly increased the blood perfusion and capillary density of ischemia hindlimb of the diabetic rats were found,which was correlated to an increased level of HIF1α and VEGF. In contrast, GDF11 Ab could lead to the opposite effects. Conclusion GDF11 treatment promotes the recovery of diabetic hindlimb ischemia, which may be related to the improvement of expression of HIF1 alpha and VEGF.

Objective To investigate the effect of growth differentiation factor 11 ( GDF11 ) on aorta in apolipoprotein E-Null( ApoE-/-) mice and its possible mechanisms. Methods Four-week-old healthy male ApoE-/-mice were fed with high-fat diet for 1 week and were then divided into 4 groups:vehicle group(n=10), GDF11 group (n=10),adeno-associated virus-green fluorescent protein group(AAV-GFP group, n=10), and AAV-GDF11 group ( n=10 ) . The mice received intraperitoneal injection with phosphate buffered saline, GDF11 protein, a single injection of purified AAV-GDF11 or AAV-GFP through the tail vein, respectively. After 4 weeks, serum GDF11/8 level and endothelium-dependent vasodilatation were detected. After 12 weeks, serum GDF11/8, interleukin-6 (IL-6), tumor necrosis factor-α( TNF-α), total cholesterol ( TC), triglycerides ( TG), oxidized low density lipoprotein(ox-LDL), and free fatty acids(FFA)levels were measured, the plaque areas in aortic enface and cross sections were measured by oil red O or HE staining, the macrophages/T lymphocytes infiltration in plaques were detected with immunohistochemistry, and the mRNA expressions of IL-6, TNF-α, and IL-10 were determined by real-time PCR. Results Compared with vehicle or AAV-GFP groups, GDF11 and AAV-GDF11 groups presented improved endothelium-dependent vasodilatation, decreased levels of blood inflammatory factors, blood lipid, reduced plaque on face area sections[Vehicle group : GDF11 group:(31. 23 ± 3. 12)% vs (17. 18 ± 2. 17) %;AAV-GFP group : AAV-GDF11 group:(38.01±4.43)% vs(14.54±2.86)%,P<0.05]andcrosssections[Vehiclegroup :GDF11 group:(19. 87 ± 2. 11)% vs (10. 32 ± 1. 47)%;AAV-GFP group : AAV-GDF11 group:(23. 02 ± 2. 76)%vs (9.06±1.63)%, P<0. 05]. There were less macrophages and T lymphocytes infiltration in plaques and lower mRNA expressions of inflammatory factors at aortic wall. Conclusion GDF11 reduces the area of atherosclerotic lesion in ApoE-/-mice, which may be involved in endothelial protection, such as to reduce inflammatory reaction, and to change cellular composition in plaques.

Humanumbilicalveinendothelialcells(HUVECs)weretreatedwith3nmol/Lliraglutidefor10, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240, and 270 minutes at the concentrations of 5. 5 or 30 mmol/L glucose. Western blot analysis was used to detected protein expression and phosphorylation of insulin receptor substrates-1 ( IRS-1 ) and endothelial nitric oxide synthase ( eNOS ) . The results showed that the baseline level of phosphorylated-eNOS/eNOS was lower in high glucose group than that in normal group(0. 239 ± 0. 016 vs 0. 400 ± 0. 02,P<0. 05). Liraglutide time-dependently increased phosphorylated-eNOS/eNOS and phosphorylated-IRS-1/IRS-1 levels at 5. 5 or 30 mmol/L glucose.

Objective: To explore the effect of irisin on atherosclerosis with possible mechanisms in diabetes mellitus (DM) mice. Methods: A total of 30 ApoE-/- mice were randomly divided into 2 groups: Control group, the mice received citrate buffer solution for modeling control,n=10. DM group, the mice received streptozotocin injection for DM modeling,n=20; the DM group was further divided into 2 subgroups as DM control (DM-C) group, the mice received normal saline injection for 12 weeks and DM + irisin group, the diabetic mice received irisin injection for 12 weeks.n=10 in each subgroup. With 4 weeks of irisin intervention, the endothelium-dependent vasodilatation was detected. With 12 weeks of intervention, the blood levels of tumor necrosis factor-α (TNF-α), high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and oxidized low-density lipoprotein (ox-LDL) were examined by ELISA, the plaque areas in aortic en face and cross sections were measured by Oil red O or HE staining, the macrophages/T lymphocytes inifltration in plaques were detected with immunohistochemistry, and the mRNA expressions of IL-6, IL-10, TNF-α were determined by RT-PCR. Results: Compared with DM-C group, DM + irisin group presented improved endothelium-dependent vasodilatation, decreased levels of blood inlfammatory factors, reduced plaque on face area sections (22.57 ± 2.17) % vs (35.09 ± 2.38) % and cross sections (19.36 ± 1.85) % vs (25.53 ± 7.87) %,P < 0.05, less macrophages (30.5 ± 2.79) % vs (41.34 ± 9.13) % T and lymphocytes infiltration (28.11 ± 4.24) % vs (35.79 ± 9.11) % in plaques and lower mRNA expressions of inflammatory factors(IL-6: 1.76 ± 0.50 vs 3.78 ± 1.15; TNF-α: 1.05 ± 0.30 vs 2.11 ± 0.48; ICAM-1: 1.96 ± 0.69 vs 2.71 ± 0.72; VCAM-1: 0.87 ± 0.21vs 1.45±0.25; MCP-1: 1.34 ± 0.34 vs 1.77 ± 0.55) at aortic wall, P<0.05.Conclusion: Irisin may improve atherosclerosis condition in ApoE-/- DM mice, the endothelial protection and antiinflammatoryreaction were the important mechanisms. Irisin has the potential for preventing/treating atherosclerosis.

Four-week-old male Sprague-Dawley rats were rendered diabetic by intraperitoneal injection of streptozotocin (STZ) after feeding high-fat-diet for 8 weeks,and divided into diabetes group and tumor necrosis factorrelated apoptosis ligand(TRAIL) group.Normal rats severed as a control group.Treatment with TRAIL lasted for 3 months.Total cholesterol,triglycerides,low-density lipoprotein-cholesterol,blood glucose,and insulin levels were decreased in TRAIL group,as compared with diabetes group.Area of atherosclerotic lesion in TRAIL group [(23.8 ± 5.7) ％] was significantly smaller than that in diabetes group [(47.6 ± 7.8) ％].It suggested that TRAIL may reduce the area of atherosclerotic lesion in diabetic rats.

Objective To explore the effect and its mechism of osteoprotegerin (OPG) on human umbilical vein endothelial cells(HUVECs) induced by high glucose.Methods (1) The cultured HUVECs were treated with normal glucose(5.5 mmol/L),high glucose(33 mmol/L),high glucose + OPG(0.5,1,and 2 μg/ml)as well as mannitol(5.5 mmol/L glucose+27.5 mmol/L mannitol) for 48 h,respectively.Flow cytometry assay and Hoechst 33258 staining were used to detect the cell apoptosis.The expression levels of Bcl-2 and Bax protein were measured by western blot analysis.(2) The cultured HUVECs were treated with normal glucose,high glucose,high glucose + OPG (2 μg/ml OPG),high glucose + rapamycin(10 ng/ml rapamycin) as well as high glucose + rapamycin + OPG for 24h,respectively.The expression levels of S6K,p-S6K,4EBP1 and p-4EBP1 protein were measured by western blot analysis.(3)The cultured HUVECs were treated with normal glucose,high glucose,high glucose + OPG(2 μg/ml)for 24 h,respectively.The expression levels of tuberin and p-tuberin protein were measured by western blot analysis.Results (1) Compared with normal glucose group,the apoptosis of HUVECs and the expression level of Bax was dramatically increased,and the expression of Bcl-2 was decreased significantly in high glucose group (P＜0.05).The apoptosis of HUVECs and the expression level of Bax in high glucose + OPG group was significantly lower than that in high glucose group,which was still higher than that in normal glucose group (P＜ 0.05).and the expression of Bcl-2 in high glucose + OPG group was significantly higher than that in high glucose group,which was still lower than that in normal glucose group (P＜0.05).There was no statistically difference between hyperosmolar control group and normal glucose group.(2) Compared with normal glucose group,the expression levels of p-S6K and p-4EBP1 were increased markedly in high glucose group(P＜0.05).The expression levels of p-S6K and p-4EBP1 in high glucose + OPG group were significantly lower than that in high glucose group,which were still higher than that in normal glucose group(P＜0.05).No significant difference was found between high glucose + OPG group and high glucose + rapamycin group.(3) Compared with normal glucose group,the expression level of p-tuberin was increased markedly in high glucose group (P ＜ 0.05).The expression level of p-tuberin in high glucose + OPG group was significantly lower than that in high glucose group,which was still higher than that in normal glucose group (P ＜0.05).Conclusions It suggests that the protective effect and mechanism of OPG on HUVECs cultured with high glucose may be association with tuberin/mTORC1 pathway.

Dynamic electrocardiography (DCG) or Holter is the best device to detect arrhythmia and can help early detection of some sudden cardiac death risk factors. The acquisition and recording system of the DCG, however, affects the data quality and the patients' comfort directly. This paper reviews the related latest studies, and discusses the importance of new ECG electrode and wireless dynamic monitoring in DCG monitoring field. Moreover, the existed main problems are summarized and classified and the prospects for the development trend are presented.
Electrocardiography, Ambulatory ; instrumentation ; trends ; Electrodes ; Humans ; Wireless Technology