Effects of laser photocoagulation on serum angiopoietin-1, angiopoietin-2, angiopoietin-1/angiopoietin-2 ratio, and soluble angiopoietin receptor Tie-2 levels in type 2 diabetic patients with proliferative diabetic retinopathy.

AIM: To determine the effects of laser photocoagulation on serum levels of angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), soluble angiopoietin receptor Tie-2 (Tie-2), Ang-1/Ang-2 ratio and vascular endothelial growth factor (VEGF) in patients with type 2 diabetes mellitus (T2DM) and proliferative diabetic retinopathy (PDR). We also explored the role of the Ang/Tie system in PDR. METHODS: 160 patients with T2DM, including 50 patients with non-diabetic retinopathy (NDR), 58 patients with non-proliferative diabetic retinopathy (NPDR), and 52 patients with PDR were enrolled in this study. Serum Ang-1, Ang-2, Tie-2 receptor and VEGF levels were measured using enzyme-linked immunosorbent assays for all patients and were repeated in 26 patients who underwent laser photocoagulation two months after the procedure. RESULTS: The median levels of Ang-2 and VEGF in serum were significantly higher in the NPDR group (4.23 ng/mL and 303.2 pg/mL, respectively) compared to the NDR group (2.67 ng/mL and 159.8 pg/mL, respectively, P<0.01), with the highest level in the PDR group (6.26 ng/mL and 531.2 pg/mL, respectively, P<0.01). The median level of Ang-1 was significantly higher in the NPDR group (10.77 ng/mL) compared to the NDR group (9.31 ng/mL) and the PDR groups (9.54 ng/mL) (P<0.05), while no difference was observed between the PDR and NDR groups. Ang-1/Ang-2 ratio of PDR group was lowest in three groups (1.49 vs 2.69 and 2.90, both P<0.01). The median level of Tie-2 was not significantly different among three groups (P>0.05). Ang-2 was positively correlated with VEGF and Tie-2 in the PDR and NPDR groups (both P<0.05). Among the 26 patients who underwent laser photocoagulation, serum Ang-2 and VEGF levels significantly decreased (both P<0.05), whereas serum Ang-1 level and Ang-1/Ang-2 ratio were weakly increased (P>0.05). The median levels of Ang-2 and VEGF in serum were highest in PDR group, however, Ang-1/Ang-2 ratio of PDR group was lowest in three groups. CONCLUSION: Laser photocoagulation can reduce serum Ang-2 and VEGF levels. The Ang/Tie system and VEGF play an important role in the development and progression of T2DM patients with PDR.

Serum phospholipid omega-3 polyunsaturated fatty acids and insulin resistance in type 2 diabetes mellitus and non-alcoholic fatty liver disease.

AIMS: To investigate the relationship between serum phospholipid omega-3 polyunsaturated fatty acids (ω-3 PUFAs) and insulin resistance (IR) in patients with type 2 diabetes mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD). METHODS: 51 patients with T2DM and NAFLD (T2DM+NAFLD group), 50 with T2DM alone (T2DM group), 45 with NAFLD alone (NAFLD group), and 42 healthy control subjects (NC group) were studied. Serum ω-3 PUFA profiles were analyzed by gas chromatography, and alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltransferase (GGT), and serum lipid concentrations were measured. Insulin resistance was assessed by the homeostasis model assessment method (HOMA-IR). RESULTS: HOMA-IR levels were higher in the T2DM+NAFLD group than in the T2DM, NAFLD and NC groups (p<0.05), as were ALT, AST, GGT, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) concentrations (p<0.05). Conversely, serum ω-3 PUFA levels were significantly lower in the T2DM+NAFLD group than in the other groups (p<0.05). The ω-3 PUFA level was negatively correlated with HOMA-IR, TC, LDL-C and TG. CONCLUSIONS: Serum phospholipid ω-3 PUFA levels were significantly decreased in patients with T2DM and NAFLD, and were negatively related with insulin resistance. Thus, reduced ω-3 PUFAs may play an important role in the development of T2DM and NAFLD.

PP121, a dual inhibitor of tyrosine and phosphoinositide kinases, inhibits anaplastic thyroid carcinoma cell proliferation and migration.

The tyrosine and phosphoinositide kinases play crucial roles in the regulation of many cancer cell processes including cell survival and cell motility. Anaplastic thyroid carcinoma (ATC) is a rare and deadly type of thyroid cancer, and so far, there are no effective therapeutic compounds for ATC. Herein, we investigate the anticancer activities of PP121, a dual inhibitor of tyrosine and phosphoinositide kinases, in ATC therapy. We found that PP121 is effective at suppressing cell viability, inducing cell apoptosis, and inhibiting cell migration and invasion. The potential anticancer mechanism for PP121 might be its inhibitory effects on phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways in ATC cells. Furthermore, PP121 is effective at suppressing ATC tumor growth in vivo. In summary, our studies suggest that PP121 might be a promising therapeutic compound for ATC treatment, which might shed new light on ATC therapy.

Additive effect by combination of Akt inhibitor, MK-2206, and PDGFR inhibitor, tyrphostin AG 1296, in suppressing anaplastic thyroid carcinoma cell viability and motility.

The phosphatidylinositol-3-kinase/Akt pathway and receptor tyrosine kinases regulate many tumorigenesis related cellular processes including cell metabolism, cell survival, cell motility, and angiogenesis. Anaplastic thyroid carcinoma (ATC) is a rare type of thyroid cancer with no effective systemic therapy. It has been shown that Akt activation is associated with tumor progression in ATC. Here we observed the additive effect between an Akt inhibitor (MK-2206) and a novel platelet-derived growth factor receptor inhibitor (tyrphostin AG 1296) in ATC therapy. We found an additive effect between MK-2206 and tyrphostin AG 1296 in suppressing ATC cell viability. The combination of MK-2206 and tyrphostin AG 1296 induces additive apoptosis, additive suppression of the Akt signaling pathway, as well as additive inhibition of cell migration and invasion of ATC cells. Furthermore, the combination of MK-2206 and tyrphostin AG 1296 induced additive suppression of ATC tumor growth in vivo. In summary, our studies suggest that the combination of Akt and receptor tyrosine kinase inhibitors may be an efficient therapeutic strategy for ATC treatment, which might shed new light on ATC therapy.

[Serum omega-3 polyunsaturated fatty acid and insulin resistance in type 2 diabetes mellitus and non-alcoholic fatty liver disease].

OBJECTIVE: To investigate the relationship between serum omega-3 polyunsaturated fatty acid (omega-3PUFA) and insulin resistance (IR) in patients with type 2 diabetes mellitus and non-alcoholic fatty liver disease (NAFLD). METHODS: This trial involved 51 patients of type 2 diabetes mellitus with NAFLD (G4 group), 50 patients of type 2 diabetes alone (G3 group), 45 patients of NAFLD alone (G2 group) and 42 healthy control subjects (G1 group). Serum omega-3PUFA profile was analyzed with capillary gas chromatography. Insulin resistance was assessed by homeostasis model assessment (HOMA-IR). ALT, AST, gamma-glutamyltransferase (GGT) and serum lipids were measured. RESULTS: The levels of HOMA-IR were higher in G4 group than those in G3, G2 and G1 group (4.90 + or - 2.54 vs 2.38 + or - 1.23, 2.20 + or - 1.15, 1.13 + or - 0.42; P < 0.05). The level of ALT, AST, GGT, TC, TG, LDL-C were higher in G4 group than those in G3, G2 and G1 group (P < 0.05). The level of omega-3PUFA was significantly lower in G4 group than those in G3, G2 and G1 group (5.68 + or - 2.02 vs 7.17 + or - 2.38, 6.97 + or - 2.32, 10.08 + or - 2.76; P < 0.05). omega-3PUFA concentration was negatively correlated with HOMA-IR, TC, TG and LDL-C (r = -0.491, -0.376, -0.462, -0.408, P < 0.05). CONCLUSIONS: Serum omega-3PUFA is significantly decreased in patients with type 2 diabetes mellitus and NAFLD. Serum omega-3PUFA is negatively correlated with insulin resistance. omega-3PUFA plays a very important role in the development of diabetes mellitus and NAFLD.

[Study on the associations between inflammatory factor and insulin resistance as well as type 2 diabetes with macrovascular complications].

OBJECTIVE: To study the possible association between C-reactive (CRP) and insulin resistance (IR) as well as the pathogenesis of type 2 diabetes macrovascular complication. METHODS: Serum CRP was measured by ultrasensitive immuoturbidimetric, which was determined on type 2 diabetes (T2DM) with or without macrovascular complication (70 and 60 cases respectively) and on normal controls (90 cases). IR was estimated by homeostasis model assessment (HOMA-IR). RESULTS: Results showed that the concentration of CRP was higher in T2DM with or without macrovascular complications than that in the healthy subjects (P < 0.01), while it was higher in diabetic patients with macrovascular complications than that in diabetic patients without macrovascular complications (P < 0.01). In diabetic patients with macrovascular complications, person correlation analysis indicated that there existed positive correlations between CRP and FINS, HOMA-IR, triglyceride (TG) while stepwise linear regression showed that usCRP and HOMA-IR, TG having linear correlation. CONCLUSION: CRP seemed to play a role in the initiation and progression of atherosclerosis in type 2 diabetes, possibly was by the way of IR.