Traumatic brain injury (TBI) is a world-wide leading health problem with high morbidity and mortality rates. Emerging studies have demonstrated that TBI is the consequence of a series of inflammatory responses in the body. The alteration of Cystatin C (Cys C) was reported in a variety of chronic inflammatory diseases and was also recommended as a biomarker for predicting renal diseases. In this study, we aimed to investigate the relationship between serum Cys C and TBI, and to evaluate the prognostic role of Cys C in TBI prediction. One hundred and seventy-six patients with TBI were recruited and 102 patients were finally analyzed, with 30 healthy control subjects. The concentrations of Cys C were significantly reduced in the healthy control group compared to the TBI group, and correlated with high GCS scores. The levels of hsCRP, counts of white blood cells, and levels of IL-6 and TNF-α were remarkably elevated in the TBI patients compared with the control group in a severity-dependent manner. Moreover, the concentration of Cys C was negatively correlated with TBI severity and positively correlated with inflammatory factors. In conclusion, serum Cys is an inflammatory cytokine-related factor and might indicate the severity of TBI thus serving as a prognostic biomarker.
Animals appoint incentive value and learn to approach otherwise behaviorally inert stimuli if these stimuli come to predict the delivery of reward. Interestingly, this adaptive Pavlovian learning process has been implicated in behavioral control disorders, such as drug addiction. One brain region implicated in directing conditioned approach behavior is the prelimbic region of the prefrontal cortex. The present study employed in vivo electrophysiology in the prelimbic cortex to characterize the distribution of neural responses to the presence of a cue that had acquired incentive value after being associated with a primary reward. Male rats were trained in a Pavlovian autoshaping task in which a lever was presented prior to reward delivery. Following repeated pairings of lever availability and reward delivery, rats pressed the lever even though reward delivery was not contingent on any interaction with the lever. Neurons in the prelimbic cortex selectively encoded the presentation of the reward-predicting lever. Although the response was heterogeneous, most responsive neurons decreased their firing rate in response to the presence of the lever. These findings characterize the varied responses of prelimbic cortical neurons to reward cues and are consistent with evidence that the role of the prelimbic cortex in reward learning depends on the downstream target.