Prolonged propagation of rat neural stem cells relies on inhibiting autocrine/paracrine bone morphogenetic protein and platelet derived growth factor signals

Continuous expansion of rat neural stem cell lines has not been achieved due to proliferation arrest and spontaneous differentiation in vitro. In the current study, neural precursor cells derived from the subventricular zone of adult rats spontaneously underwent astroglial and oligodendroglial differentiation after limited propagation. This differentiation was largely induced by autocrine or paracrine bone morphogenetic protein and platelet derived growth factor signals. The results showed that, by inhibiting bone morphogenetic protein and platelet derived growth factor signals, adult rat neural precursor cells could be extensively cultured in vitro as tripotent stem cell lines. In addition to adult rat neural stem cells, we found that bone morphogenetic protein antagonists can promote the proliferation of human neural stem cells. Therefore, the present findings illustrated the role of autocrine or paracrine bone morphogenetic protein and platelet derived growth factor signaling in determining neural stem cell self-renewal and differentiation. By antagonizing both signals, the long-term propagation of rat neural stem cell lines can be achieved.

Disseminated intravascular coagulation scores as predictors for progressive hemorrhage and neurological prognosis following traumatic brain injury

Coagulation abnormalities, such as disseminated intravascular coagulation （DIC）, are associated with progressive hemcrrhagic injury （PHI） following head trauma. However, the exact relationship between coagulopathy and PHI remains unclear. The present study utilized a scoring system defined by the International Society of Thrombosis and Haemostasis to investigate whether a high DIC score is predictive for PHI. This study was a multicenter prospective design involving four hospitals, a 6-month observation, and follow-up. Of 352 traumatic brain injury （TBI） patients, serial CT scan indicated approximately one third of patients developed progressive hemorrhage, which was most frequently observed in the frontal, temporal, and orbitofrontal lobes of patients with brain contusion. PHI-positive patients exhibited poor prognosis, as indicated by prolonged length of hospital/intensive care unit stay and high mortality. More importantly, a DIC score after TBI, as well as patient age and sex, could serve as predictors for PHI. In addition, DIC scores were closely associated with injury severity. Therefore, the DIC scoring system facilitated early PHI diagnosis in TBI patients, and DIC scores might serve as a valuable predictor for TBI patients with PHI.