Background: Acetaminophen (APAP) overdose induces massive hepatocyte necrosis. Necrotic tissue releases high mobility group B1 (HMGB1), and HMGB1 contributes to liver injury. Even though blockade of HMGB1 does not protect against APAP-induced acute liver injury (ALI) at 9 h time point, the later time points are not studied and the role of HMGB1 in APAP overdose is unknown, it is possible that neutralization of HMGB1 might improve hepatocyte regeneration. This study aims to test whether blockade of HMGB1 improves hepatocyte regeneration after APAP overdose. Methods: Male C57BL/6 mice were treated with a single dose of APAP (350 mg/kg). 2 hrs after APAP administration, the APAP challenged mice were randomized to receive treatment with either anti-HMGB1 antibody (400 μg per dose) or non-immune (sham) IgG every 24 hours for a total of 2 doses. Results: 24 hrs after APAP injection, anti-HMGB1 therapy instead of sham IgG therapy significantly improved hepatocyte regeneration microscopically; 48 hrs after APAP challenge, the sham IgG treated mice showed 14.6% hepatic necrosis; in contrast, blockade of HMGB1 significantly decreased serum transaminases (ALT and AST), markedly reduced the number of hepatic inflammatory cells infiltration and restored liver structure to nearly normal; this beneficial effect was associated with enhanced hepatic NF-κB DNA binding and increased the expression of cyclin D1, two important factors related to hepatocyte regeneration. Conclusion: HMGB1 impairs hepatocyte regeneration after APAP overdose; Blockade of HMGB1 enhances liver recovery and may present a novel therapy to treat APAP overdose.

Background—: Macrophage (MΦ) infiltration and smooth muscle cell (SMC) proliferation are hallmarks of atherosclerosis and unstable plaques. Neuroimmune guidance cue 1 (netrin-1 [NTN1]) plays a critical role controlling MΦ trafficking and SMC activation. Characterization of expression of NTN1 and its receptors and their association with plaque stability in human(s) is lacking. Methods and Results—: The expression of NTN1 and its receptors did not differ in either whole blood or circulating monocytes from patients with coronary artery disease (n=55) compared with healthy controls (n=45). However, NTN1 was downregulated (−2.9-fold; P <0.0001) and UNC5B upregulated (2.2-fold; P <0.0001) in atherosclerotic plaques (n=68), whereas there were no differences in other NTN1 receptors compared with histologically normal controls (n=28). Increased UNC5B expression is associated with histologically more stable plaques ( P =0.011). NTN1 expression correlated positively with SMC markers and signatures and negatively with inflammatory markers and M1 and especially M2 signatures in the atherosclerotic plaques. UNC5B clustering correlated positively with inflammatory and MΦ markers. NTN1 protein colocalized with CD68-positive cells of monocytic origin and muscle-actin-specific-antibody (HHF3)-positive cells indicative of SMCs in the plaques and only with SMCs in the control samples. NTN1 protein was highly expressed in the intimal layer of the control vessels. Conclusions—: Present findings provide support for the hypothesis that dysregulation of expression of NTN1 in SMCs and its chemorepulsive receptor UNC5B in macrophages are involved in the development of atherosclerosis and unstable plaques.

Background and Purpose—Cerebral small vessel disease reflected by white matter lesions (WMLs) in MRI and kidney function reflected by estimated glomerular filtration rate (eGFR) is closely associated in patients without stroke. We studied whether eGFR and WMLs predict long-term survival in patients with acute stroke. Methods—After exclusion of patients with low eGFR (N=5 [1.3%]; <30 mL/min/1.73 m2), consecutive patients with acute stroke (N=378) subjected to MRI and serum creatinine determination were included in the study and prospectively followed-up up to 12 years. Results—Of the patients, 71.2% had died during the follow-up, 152 (40.2%) had moderate (eGFR <60 mL/min/1.73 m2), and 226 (59.8%) had normal or mildly impaired eGFR (≥60 mL/min/1.73 m2). Of the patients, 108 (28.6%) had mild, 68 (18.0%) had moderate, and 202 (53.4%) had severe WMLs. In logistic regression analysis adjusted with age and sex, eGFR <60 mL/min/1.73 m2 was associated with severe WMLs (relative risk 2.77, 95% CI 1.10 to 6.98, P=0....