Quantitative Lipid Profiling Reveals Major Differences between Liver Organoids with Normal Pi*M and Deficient Pi*Z Variants of Alpha-1-antitrypsin

Chaperone-mediated autophagy degrades SERPINA1E342K/α1-antitrypsin Z variant and alleviates cell stress

Chaperone-mediated autophagy (CMA) is a specific form of autophagy that selectively targets proteins containing a KFERQ-like motif and relies on the chaperone protein HSPA8/HSC70 for substrate recognition. In SERPINA1/a1-antitrypsin deficiency (AATD), a disease characterized by the hepatic buildup of the SERPINA1E342K/ATZ, CMA's role had been unclear. This work demonstrates the critical role that CMA plays in preventing SERPINA1E342K/ATZ accumulation; suppressing CMA worsens SERPINA1E342K/ATZ accumulation while activating it through chemical stimulation or LAMP2A overexpression promotes SERPINA1E342K/ATZ breakdown. Specifically, SERPINA1E342K/ATZ's 121QELLR125 motif is critical for HSPA8/HSC70 recognition and LAMP2A's charged C-terminal cytoplasmic tail is vital for substrate binding, facilitating CMA-mediated degradation of SERPINA1E342K/ATZ. This selective activation of CMA operates independently of other autophagy pathways and alleviates SERPINA1E342K/ATZ aggregate-induced cellular stress. In vivo administration of AR7 promotes hepatic SERPINA1E342K/ATZ elimination and mitigates hepatic SERPINA1E342K/ATZ aggregation pathology. These findings highlight CMA's critical function in cellular protein quality control of SERPINA1E342K/ATZ and place it as a novel target for AATD treatment.Abbreviation: AR7: atypical retinoid 7; ATG16L1: autophagy related 16 like 1; AATD: SERPINA1/alpha-1 antitrypsin deficiency; CHX: cycloheximide; CMA: chaperone-mediated autophagy; CQ: chloroquine; ER: endoplasmic reticulum; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; HSPA8/HSC70: heat shock protein family A (Hsp70) member 8; LAMP2A: lysosomal associated membrane protein 2A; LAMP2B: lysosomal associated membrane protein 2B; LAMP2C: lysosomal associated membrane protein 2C; MG132: carbobenzoxy-L-leucyl-L-leucyl-L-leucinal; PAS-D: periodic acid-Schiff plus diastase; SERPINA1/A1AT: serpin family A member 1; SERPINA1E342K/ATZ: Z variant of SERPINA1; TMRE: tetramethyl rhodamine ethyl ester perchlorate.

Bioinformatic analysis of serpina1 expression in papillary thyroid carcinoma and its potential association with Hashimoto's thyroiditis

PURPOSE

Previous studies have suggested that SERPINA1 may promote a better prognosis in papillary thyroid carcinoma (PTC) along with Hashimoto's thyroiditis (HT). This study aims to further explore the role of the SERPINA1 gene in PTC and its relationship with HT using multiple databases.

METHODS

Transcriptomic data from The Cancer Genome Atlas (TCGA) were utilized to analyze differences in SERPINA1 expression between PTC patients with and without HT. The expression levels of SERPINA1 in tumor tissues and its association with tumor characteristics were assessed using the Wilcoxon test across both patient groups. The impact of SERPINA1 expression on immune cell infiltration in PTC was evaluated using the CIBERSORT tool. Single-cell transcriptomic data from the Gene Expression Omnibus (GEO) were further analyzed to identify SERPINA1-expressing subpopulations based on Thyroid Differentiation Score (TDS) and pseudotime analysis. Gene Set Variation Analysis (GSVA) was employed to characterize pathways associated with SERPINA1, inferring its potential functions. Finally, CellChat was used to investigate key ligand-receptor interactions between SERPINA1-positive subpopulations and other cell types.

RESULTS

TCGA data analysis reveals that, compared to normal thyroid tissue, the transcriptional level of SERPINA1 is significantly elevated in PTC tissues. Moreover, the expression of SERPINA1 is closely linked to certain clinical pathological features of PTC and the infiltration of immune cells in the tumor microenvironment. Single-cell transcriptome analysis reveals that SERPINA1 is primarily expressed in thyrocytes and myeloid cells. In thyrocytes, SERPINA1 is associated with complement-related proteins (e.g., C3, CD55). In poorly differentiated thyrocytes, it is linked to protease inhibitors and epithelial-mesenchymal transition (EMT) pathways, while in moderately differentiated thyrocytes, it associates with apolipoproteins APOE and APOC1. In macrophages, SERPINA1 is highly expressed in HT-associated macrophages and unpolarized macrophages, correlating with inflammation and extracellular matrix regulation pathways. Cell-cell interaction analysis indicates that SERPINA1-positive cells interact with other cells in the tumor microenvironment through macrophage migration inhibitory factor (MIF) and fibronectin 1 (FN1).

CONCLUSION

Compared to normal thyroid tissue or cells, the expression level of SERPINA1 is elevated in PTC. In cancer cells, SERPINA1 may be associated with the complement system and complement regulator functions. In poorly differentiated thyrocytes, SERPINA1 may primarily function as a protease inhibitor and is closely related to FN1. In moderately differentiated thyrocytes, SERPINA1 is associated with apolipoproteins. In unpolarized macrophages, the function of SERPINA1 may be to act as a serine protease inhibitor, participating in the remodeling of the extracellular matrix. In macrophages within an HT environment, the elevated expression of SERPINA1 may serve as a protective mechanism to limit inflammation. In the tumor microenvironment coexisting with HT, SERPINA1 outside the tumor cells may enter the tumor cells through lipid metabolism pathways. The potential role of SERPINA1 in PTC progression is complex, and the findings of this study require further validation.

Patient-derived organoid models to decode liver pathophysiology

Liver diseases represent a growing global health challenge, and the increasing prevalence of obesity and metabolic disorders is set to exacerbate this crisis. To meet evolving regulatory demands, patient-specific in vitro liver models are essential for understanding disease mechanisms and developing new therapeutic approaches. Organoid models, which faithfully recapitulate liver biology, can be established from both non-malignant and malignant liver tissues, offering insight into various liver conditions, from acute injuries to chronic diseases and cancer. Improved understanding of liver microenvironments, innovative biomaterials, and advanced imaging techniques now facilitate comprehensive and unbiased data analysis, paving the way for personalised medicine. In this review, we discuss state-of-the-art patient-derived liver organoid models, recent technological advancements, and strategies to enhance their clinical impact.

Mitochondrial dysfunction and impaired DNA damage repair through PICT1 dysregulation in alveolar type II cells in emphysema

BACKGROUND

Alveolar type II (ATII) cells have a stem cell potential in the adult lung and repair the epithelium after injury induced by harmful factors. Their damage contributes to emphysema development, characterized by alveolar wall destruction. Cigarette smoke is the main risk factor for this disease development.

METHODS

ATII cells were obtained from control non-smoker and smoker organ donors and emphysema patients. Isolated cells were used to study the role of PICT1 in this disease. Also, a cigarette smoke-induced murine model of emphysema was applied to define its function in disease progression further.

RESULTS

Decreased PICT1 expression was observed in human and murine ATII cells in emphysema. PICT1 was immunoprecipitated, followed by mass spectrometry analysis. We identified MRE11, which is involved in DNA damage repair, as its novel interactor. PICT1 and MRE11 protein levels were decreased in ATII cells in this disease. Moreover, cells with PICT1 deletion were exposed to cigarette smoke extract. This treatment induced cellular and mitochondrial ROS, cell cycle arrest, nuclear and mitochondrial DNA damage, decreased mitochondrial respiration, and impaired DNA damage repair.

CONCLUSIONS

This study indicates that PICT1 dysfunction can negatively affect genome stability and mitochondrial activity in ATII cells, contributing to emphysema development. Targeting PICT1 can lead to novel therapeutic approaches for this disease.

Research progress and application of liver organoids for disease modeling and regenerative therapy

The liver is a major metabolic organ of the human body and has a high incidence of diseases. In recent years, the annual incidence of liver disease has increased, seriously endangering human life and health. The study of the occurrence and development mechanism of liver diseases, discovery of new therapeutic targets, and establishment of new methods of medical treatment are major issues related to the national economy and people's livelihood. The development of stable and effective research models is expected to provide new insights into the pathogenesis of liver diseases and the search for more effective treatment options. Organoid technology is a new in vitro culture system, and organoids constructed by human cells can simulate the morphological structure, gene expression, and glucose and lipid metabolism of organs in vivo, providing a new model for related research on liver diseases. This paper reviews the latest research progress on liver organoids from the establishment of cell sources and application of liver organoids and discusses their application potential in the field of liver disease research.

Diagnostic and therapeutic value of human serpin family proteins

SERPIN (serine proteinase inhibitors) is an acronym for the superfamily of structurally similar proteins found in animals, plants, bacteria, viruses, and archaea. Over 1500 SERPINs are known in nature, while only 37 SERPINs are found in humans, which participate in inflammation, coagulation, angiogenesis, cell viability, and other pathophysiological processes. Both qualitative or quantitative deficiencies or overexpression and/or abnormal accumulation of SERPIN can lead to diseases commonly referred to as "serpinopathies". Hence, strategies involving SERPIN supplementation, elimination, or correction are utilized and/or under consideration. In this review, we discuss relationships between certain SERPINs and diseases as well as putative strategies for the clinical explorations of SERPINs.

An association between plasma levels of α2-macroglobulin and α1-antitrypsin in PiMM and PiZZ individuals differing in COPD presentation

INTRODUCTION

Compared to normal PiMM, individuals with severe α1-antitrypsin (AAT) PiZZ (Glu342Lys) genotype deficiency are at higher risk of developing early-onset chronic obstructive pulmonary disease (COPD)/emphysema associated with Z-AAT polymers and neutrophilic inflammation. We aimed to investigate putative differences in plasma levels of acute phase proteins (APP) between PiMM and PiZZ subjects and to determine plasma Z-AAT polymer levels in PiZZ subjects.

MATERIALS AND METHODS

Nephelometric analysis of seven plasma APPs was performed in 67 PiMM and 44 PiZZ subjects, of whom 43 and 42, respectively, had stable COPD. Of the PiZZ-COPD patients, 21 received and 23 did not receive intravenous therapy with human AAT preparations (IV-AAT). Plasma levels of Z-AAT polymers were determined by Western blotting using specific mouse monoclonal antibodies (2C1 and LG96).

RESULTS

In addition to lower plasma AAT, PiZZ patients had higher α2-macroglobulin (A2MG) levels than PiMM patients. In contrast, PiZZ who received IV-AAT had higher AAT values but lower A2MG values than PiZZ without IV-AAT. Regardless of the AAT genotype, AAT levels were inversely correlated with A2MG, and the AAT/A2MG ratio was correlated with lung diffusion capacity (DCLO%). All PiZZ patients had circulating Z-AAT polymer levels that correlated directly with A2MG. In PiZZ without IV-AAT therapy polymer levels correlated inversely with the ratio of forced expiratory volume in 1 s to forced vital capacity (FEV1/FVC).

CONCLUSION

Combined measurement of plasma AAT and A2MG levels may be of clinical value in assessing the progression of COPD and requires further attention.