Heme oxygenase 1-mediated ferroptosis in Kupffer cells initiates liver injury during heat stroke.

With the escalating prevalence of global heat waves, heat stroke has become a prominent health concern, leading to substantial liver damage. Unlike other forms of liver injury, heat stroke-induced damage is characterized by heat cytotoxicity and heightened inflammation, directly contributing to elevated mortality rates. While clinical assessments have identified elevated bilirubin levels as indicative of Kupffer cell dysfunction, their specific correlation with heat stroke liver injury remains unclear. Our hypothesis proposes the involvement of Kupffer cell ferroptosis during heat stroke, initiating IL-1ß-mediated inflammation. Using single-cell RNA sequencing of murine macrophages, a distinct and highly susceptible Kupffer cell subtype, Clec4F+/CD206+, emerged, with heme oxygenase 1 (HMOX-1) playing a pivotal role. Mechanistically, heat-induced HMOX-1, regulated by early growth response factor 1, mediated ferroptosis in Kupffer cells, specifically in the Clec4F+/CD206+ subtype (KC2), activating phosphatidylinositol 4-kinase beta and promoting PI4P production. This cascade triggered NLRP3 inflammasome activation and maturation of IL-1ß. These findings underscore the critical role of targeted therapy against HMOX-1 in ferroptosis within Kupffer cells, particularly in Clec4F+/CD206+ KCs. Such an approach has the potential to mitigate inflammation and alleviate acute liver injury in the context of heat stroke, offering a promising avenue for future therapeutic interventions.

TRPV1/cPLA2/AA pathway contributes to ferroptosis-mediated acute liver injury in heatstroke.

With the increasing frequency of global heatwaves, the incidence of heatstroke (HS) is significantly rising. The liver plays a crucial role in metabolism and is an organ highly sensitive to temperature. Acute liver injury (ALI) frequently occurs in patients with HS, yet the exact mechanisms driving ALI in HS are still unknown. In this basic study, we investigated the specific molecular mechanisms by which cytosolic phospholipase A2 (cPLA2) mediates ferroptosis, contributing to the development of ALI following HS. We utilized a mouse model of HS and divided the mice into healthy control and HS groups for a series of experiments. Firstly, we assessed oxidative damage markers in tissues and cells, as well as ferroptosis biomarkers. Additionally, we conducted a non-targeted metabolomics analysis to validate the role of key enzymes in metabolism and the ferroptosis pathway. Our results indicated that ferroptosis contributed to the progression of ALI after HS. Administering the ferroptosis inhibitor liproxstatin-1 (10 mg/kg) post-HS onset significantly inhibits HS-induced ALI progression. Mechanistically, heatstroke triggered cPLA2 activation and increased the levels of its metabolic product, arachidonic acid, thereby further promoted the occurrence of ferroptosis. Furthermore, heatstroke mediated cPLA2 activation might involve enhancing transient receptor potential vanilloid subtype 1 (TRPV1) receptor function. Overall, these results highlighted the critical role that cPLA2-mediated ferroptosis plays in the development of ALI following HS, indicating that inhibiting cPLA2 may present a novel therapeutic approach to prevent ALI after HS by limiting liver cell death.

Oral magnesium prevents acetaminophen-induced acute liver injury by modulating microbial metabolism.

Acetaminophen overuse is a common cause of acute liver failure (ALF). During ALF, toxins are metabolized by enzymes such as CYP2E1 and transformed into reactive species, leading to oxidative damage and liver failure. Here, we found that oral magnesium (Mg) alleviated acetaminophen-induced ALF through metabolic changes in gut microbiota that inhibit CYP2E1. The gut microbiota from Mg-supplemented humans prevented acetaminophen-induced ALF in mice. Mg exposure modulated Bifidobacterium metabolism and enriched indole-3-carboxylic acid (I3C) levels. Formate C-acetyltransferase (pflB) was identified as a key Bifidobacterium enzyme involved in I3C generation. Accordingly, a Bifidobacterium pflB knockout showed diminished I3C generation and reduced the beneficial effects of Mg. Conversely, treatment with I3C or an engineered bacteria overexpressing Bifidobacterium pflB protected against ALF. Mechanistically, I3C bound and inactivated CYP2E1, thus suppressing formation of harmful reactive intermediates and diminishing hepatocyte oxidative damage. These findings highlight how interactions between Mg and gut microbiota may help combat ALF.

Pre-Implantation Genetic Testing for Aneuploidy on a Semiconductor Based Next-Generation Sequencing Platform.

Next-generation sequencing has gained increasing importance in the clinical application in the determination of genetic variants. In the pre-implantation genetic test, this technique has its unique advantages in scalability, throughput, and cost. For the pre-implantation genetic test for aneuploidy analysis, the semiconductor-based next-generation sequencing (NGS) system presented here provides a comprehensive approach to determine structural genetic variants at a minimum resolution of 8 Mb. From sample acquisition to the final report, the working process requires multiple steps with close adherence to protocols. Since various critical steps could determine the outcome of amplification, quality of the library, coverage of reads, and output of data, descriptive information with visual demonstration other than words could offer more detail to the operation and manipulation, which may have a great impact on the results of all critical steps. The methods presented herein will display the procedures involved in whole genome amplification (WGA) of biopsied Trophectoderm (TE) cells, genomic library construction, sequencer management, and finally, generating copy number variants' reports.