Drug-induced liver injury (DILI) is an important cause of acute liver failure, with limited therapeutic options. During DILI, oncotic necrosis with concomitant release and recognition of intracellular content amplifies liver inflammation and injury. Among these molecules, self-DNA has been widely shown to trigger inflammatory and autoimmune diseases; however, whether DNA released from damaged hepatocytes accumulates into necrotic liver and the impact of its recognition by the immune system remains elusive. Here we show that treatment with two different hepatotoxic compounds (acetaminophen and thioacetamide) caused DNA release into the hepatocyte cytoplasm, which occurred in parallel with cell death in vitro. Administration of these compounds in vivo caused massive DNA deposition within liver necrotic areas, together with an intravascular DNA coating. Using confocal intravital microscopy, we revealed that liver injury due to acetaminophen overdose led to a directional migration of neutrophils to DNA-rich areas, where they exhibit an active patrolling behavior. DNA removal by intravenous DNASE1 injection or ablation of Toll-like receptor 9 (TLR9)-mediated sensing significantly reduced systemic inflammation, liver neutrophil recruitment, and hepatotoxicity. Analysis of liver leukocytes by flow cytometry revealed that emigrated neutrophils up-regulated TLR9 expression during acetaminophen-mediated necrosis, and these cells sensed and reacted to extracellular DNA by activating the TLR9/NF-jB pathway. Likewise, adoptive transfer of wild-type neutrophils to TLR9 2/2 mice reversed the hepatoprotective phenotype otherwise observed in TLR9 absence. Conclusion: Hepatic DNA accumulation is a novel feature of DILI pathogenesis. Blockage of DNA recognition by the innate immune system may constitute a promising therapeutic venue. (HEPATOLOGY 2015;61:348-360) See Editorial on Page 35 D rug-induced liver injury (DILI) is a serious condition, with a high mortality rate and limited therapeutic alternatives.1 Among these

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Estrogen receptors, in addition to the androgen receptor (AR), are expressed at high levels in efferent ductules of the male reproductive tract and it is now well recognized that estrogen receptor (ER) a is required for the maintenance of normal structure and function of the ductules. However, little is known regarding the hormonal regulation of the receptors themselves in the male. In the present study, efferent ductule ligation and castration, followed by replacement with testosterone, dihydrotestosterone (DHT) or estradiol was used to investigate the relative importance of circulating and luminal sources of steroid for the modulation of ERa, ERb and AR in rat efferent ductules. Uni-or bilateral castration and ligation did not affect the expression of ERa and ERb, but bilateral castration caused down-regulation of AR. Replacement with DHT and testosterone alone or in combination with estradiol caused the recovery of AR expression to control levels. A slight recovery of AR was also observed after estrogen replacement. ERa expression was decreased to nearly undetectable levels after estrogen replacement. On the other hand, ERb did not show evident effects following any of the treatments, suggesting a constitutive expression of this receptor. This differential modulation of the steroid hormone receptors highlights the importance of maintaining a physiological androgen-estrogen balance to regulate the structure and function of efferent ductules in the male.

This work aims to investigate the influence of the formation of ion pairing between all-trans retinoic acid (RA) and a lipophilic amine (stearylamine; STE) on the drug encapsulation efficiency (EE) and stability of solid lipid nanoparticles (SLNs). The SLNs were characterized for EE and size. The EE and particle size were significantly improved and reduced, respectively, when the surfactant or co-surfactant concentration increased. However, while the formulation without STE allowed only 13% of RA encapsulation, the EE for RA-STE-loaded SLNs was 94%. The stability studies showed a significant decrease in EE for the SLNs without STE, while, for SLNs loaded with RA and STE, the EE remained constant after 360 days. The interactions among ion pairing components and the lipid matrix were investigated through small-angle X-ray scattering (SAXS). The SAXS analysis revealed the presence of RA in the crystalline form in SLNs without ion pairing, while crystalline RA was not observed in SLNs loaded with RA/amine. Skin irritation studies showed that the SLNs loaded with the ion pairing were significantly less irritating when compared to the marketed RA-cream. This novel SLN formulation represents a promising alternative for topical treatment of acne with RA.

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