Sexual dimorphism of acetaminophen-induced liver injury and regeneration

摘要 扑热息痛(乙酰对氨基酚或APAP)是最常用的止痛药 在美国，对乙酰氨基酚过量是发达国家急性肝功能衰竭的主要原因。 目前唯一可用的治疗方法是N-乙酰半胱氨酸(NAC)，它只有一个很短的窗口 有效性，或最终肝移植。因此，治疗APAP过量的治疗方法有 临床上急需的。该提案将通过破译以下机制来解决这一问题 APAP诱导的肝损伤和修复的性别二型性，并通过 确定激素治疗将如何加速APAP过量后男女患者的肝脏恢复。 性激素及其受体在许多肝脏过程中被认为是导致性别二型性的因素。 具体地说，女性生长激素(GH)分泌的平均水平较高有助于更高的代谢 他们肝脏中的活动。与文献一致，我们的初步数据支持女性更高的抵抗力 小鼠对APAP的作用，表现为肝坏死、细胞死亡和血清损伤标志物的检测与对照组相比减少 男性。此外，我们的单细胞RNA测序分析表明，女性肝细胞和内皮细胞 (ECS)表达的GH受体和GH途径激活水平显著高于雄性细胞，而雄性细胞 上调炎症和细胞死亡途径的激活。在为此应用程序做准备时，我们 产生的初步数据显示，生长激素治疗显著并迅速修复了两名男性的组织 雌鼠服用亚致死剂量的APAP，通过组织坏死、细胞死亡和小鼠存活来量化。 这些关键数据表明，女性具有性别二态的肝脏再生优势，这一优势可以概括出来 使用生长激素治疗，以诱导男性康复，加速女性康复。因此，我们假设 APAP敏感度中存在性别二态，我们可以通过使用GH来利用这一点 促进两性肝脏再生。在这项建议中，我们会进一步研究总督府及其 APAP过量给药后肝细胞和内皮细胞通路激活的单细胞RNA测序分析 肝细胞和EC特异性生长激素受体基因敲除。我们将利用这些发现来建立一个最佳的 GH治疗，确定GH特定剂量和男女有效时间框架以减轻肝脏 与目前的标准护理NAC相比，它具有更好的疗效，并能促进肝脏再生。潜力 GH/NAC联合治疗的附加疗效也将被确定。总之， 了解APAP所致肝损伤性别差异背后的生物学机制 生长激素的再生和调节将为建立生长激素治疗方法提供生物学基础 APAP过量在男女中都存在，这是目前尚未得到满足的临床需求。

ABSTRACT Acetaminophen (acetyl-para-aminophenol or APAP) is the most commonly used pain reliever in the United States, yet acetaminophen overdose is the leading cause of acute liver failure in the developed world. Currently the only available treatments are N-acetyl cysteine (NAC), which only has a short window of effectiveness, or ultimately liver transplant. Therefore, therapeutic alternatives to treat APAP overdose are urgently needed in the clinic. This proposal will address this issue by deciphering the mechanisms of sexual dimorphism of APAP-induced liver injury and repair, and to leverage this sexual dimorphism by establishing how hormone therapy will accelerate liver recovery in both sexes following APAP overdose. Sex hormones and their receptors have been implicated in driving sexual dimorphism in many liver processes. Specifically, higher average levels of growth hormone (GH) secretion in females contributes to higher metabolic activity in their livers. Consistent with the literature, our preliminary data support the higher resistance of female mice to APAP, shown by reduced liver necrosis, cell death, and detection of serum injury markers compared to males. Moreover, our single-cell RNA sequencing analyses reveal that female hepatocytes and endothelial cells (ECs) express significantly higher levels of GH receptor and GH pathway activation than male cells, while males have upregulated inflammatory and cell death pathway activation. In preparation for this application, we generated preliminary data showing that GH treatment significantly and rapidly repairs the tissues of both males and females following sub-lethal doses of APAP, as quantified by tissue necrosis, cell death, and mouse survival. These key data suggest a sexually dimorphic liver regenerative advantage in females, which can be recapitulated with GH treatment to induce recovery in males and accelerate recovery in females. Therefore, we hypothesize that there is a sexual dimorphism in APAP sensitivity that we can leverage with the use of GH to accelerate liver regeneration in both sexes. In this proposal, we will further examine the role of GH and its pathway activation in hepatocytes and ECs following APAP overdose via single-cell RNA sequencing analysis and hepatocyte and EC -specific GH receptor knockouts. We will leverage these findings to establish an optimal GH therapy with identification of GH specific doses and time frame of effectiveness for each sex to mitigate liver injury and accelerate liver regeneration with superior efficacy to the current standard-of-care NAC. Potential additive therapeutic effect of combined GH/NAC treatment will be also determined. In conclusion, understanding the biological mechanisms behind the sexual disparity in APAP-induced liver injury, subsequent regeneration, and modulation by GH will provide the biological foundation to establish a GH therapy to treat APAP overdose in both sexes, a currently unmet clinical need.