High altitude (HA), with the main feature of hypobaric hypoxia, is an independent risk factor for thrombosis. However, little is known on the alterations of fibrinolytic system in adaptation to HA....

To explore the correlations between RBCs indexes and the basic coagulation parameters, and provide data for further studies on high altitude-induced thrombotic disease. A total of eligible 433 volunteers were divided into different groups according to HGB concentration and HCT, respectively. PT, APTT, TT and Fbg were measured by clotting assays. HGB content, HCT and PLT count were assessed by automated hematology analyzer. APTT and PT were significantly higher in group 4 (high HGB or HCT groups) (p < 0.05 for all comparison) and PLT count was significantly lower in group 4 than in other groups (p < 0.01 for all comparison). APTT and PT showed negative correlations with HGB concentration (r = -0.168 and -0.165 resp.; both p < 0.01), whereas positive correlations were found between APTT and HCT, PT and HCT (r = 0.225 and 0.258, resp.; both p < 0.01). PLT, TT and Fbg showed no correlation with HGB and HCT. HGB and HCT may not correlate with basic coagulation parameters in high altitude population, their predictive value for high altitude-induced thrombotic disease may relatively independent and this remain to be determined in further studies.

GDF11, a member of TGF-β superfamily, has recently received widespread attention as a novel anti-ageing/rejuvenation factor to reverse age-related dysfunctions in heart and skeletal muscle, and to induce angiogenesis and neurogenesis. However, these positive effects of GDF11 were challenged by several other studies. Furthermore, the mechanism is still not well understood. In the present study, we evaluated the effects of GDF11 on C17.2 neural stem cells. GDF11 induced differentiation and apoptosis, and suppressed migration of C17.2 neural stem cells. In addition, GDF11 slightly increased cell viability after 24 h treatment, showed no effects on proliferation for about 10 days of cultivation, and slightly decreased cumulative population doubling for long-term treatment (p < 0.05). Phospho-proteome profiling array displayed that GDF11 significantly increased the phosphorylation of 13 serine/threonine kinases (p < 0.01), including p-p38, p-ERK and p-Akt, in C17.2 cells, which implied the activation of MAPK pathway. Western blot validated that the results of phospho-proteome profiling array were reliable. Based on functional analysis, we demonstrated that the differentially expressed proteins were mainly involved in signal transduction which was implicated in cellular behavior. Collectively, our findings suggest that, for neurogenesis, GDF11 might not be the desired rejuvenation factor, but a potential target for pharmacological blockade.

According to the international guidelines, fresh frozen plasma (FFP) is unanimously used to treat coagulation disorders. The quality of FFP is critical for the clinical transfusion. Till now, few studies have integratedly evaluated the differences of FFP from blood donors at between high altitude (HA) and low altitude (LA). Besides, there were no special quality standards for HA FFP in China. Up to 41 HA (Lhasa, 3700 m) and 46 LA (Chengdu, 500 m) blood donors were included in our study to estimate the differences of FFP from HA and LA blood donors. The concentration of total plasma proteins, prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time (TT), fibrinogen (Fbg), factor (F) II, FV, FVII, FVIII, FIX, FX, FXI, FXII, D-dimer, protein C (PC), protein S (PS), antithrombin III (ATIII) and von Willebrand factor antigen (vWF:Ag) were determined, respectively. As compared with FFP of LA blood donors, the total protein content of HA blood donors showed a significant decrease (65.2±8.9 vs.57.2±6.3 g/L; p<0.001); PT, aPTT, TT were significantly increased (p<0.001); the levels of FII, FV, FVII, FVIII, FIX, FX, FXI, FXII and vWF:Ag were notably decreased (all p<0.05), whereas Fbg and D-dimer were dramaticly increased (p = 0.038). Additionly, in HA blood donors, vWF: Ag and FVIII:C of O-group was significantly lower (p<0.05) than that of non-O-group. It should be noted that FVIII:C of HA blood donors (0.64±0.10 IU/mL) was lower than the current Chinese quality requirements for FFP (≥ 0.7 IU/ml). No significant differences were observed in PC, PS and ATIII. In general, our findings showed that the quality of FFP was significantly different between HA and LA blood donors, and the current Chinese quality requirements of FFP are not suitable for HA FFP. Therefore, setting up a special quality requirement for HA is quite necessary and meaningful.