{"title":"Laminin Receptors in Peripheral Tissues: Functions Revealed by Analysis of Knockout Mice.","authors":"Wanling Xuan, Yao Yao","doi":"10.1016/j.ajpath.2025.08.007","DOIUrl":"10.1016/j.ajpath.2025.08.007","url":null,"abstract":"<p><p>Laminin, by interacting with its receptors (mainly integrins and dystroglycan), exerts a variety of important functions in multiple organs. Loss-of-function studies have described the essential roles of laminin receptors in both physiological and pathologic conditions. This review summarizes the pathology and loss-of-function phenotypes of laminin receptors, including integrin-α3, integrin-α6, integrin-α7, integrin-β1, integrin-β4, and dystroglycan, focusing on the skin, kidney, skeletal muscle, peripheral nervous system, mammary gland, lung, and heart. To explore the functional redundancy/compensation among different laminin receptors, the phenotypes of compound knockout mice are compared with that of single mutants. Next, key signaling pathways downstream of each laminin receptor are summarized and compared. In addition, key questions in the field and future directions are also discussed. The aim of this review was to provide a synthetic review on loss-of-function studies of laminin receptors and foster the formation and testing of new hypotheses in the field.</p>","PeriodicalId":7623,"journal":{"name":"American Journal of Pathology","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145058228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Role of Extracellular Vesicle-Derived miRNA in the Atherosclerotic Burden.","authors":"Alessandra S Rizzuto, Isabella Fichtner, Stefano Carugo, Annalisa Radeghieri, Chiara Macchi, Massimiliano Ruscica","doi":"10.1016/j.ajpath.2025.08.006","DOIUrl":"10.1016/j.ajpath.2025.08.006","url":null,"abstract":"<p><p>In the context of atheroma-related sequelae, the role of extracellular vesicles (EVs) continues to spike interest. Their ability to traffic molecular cargo between cells highlights their role in intercellular communication, and consequently their involvement in mediating molecular events at the basis of physiological and pathologic processes. EVs encapsulate miRNAs within their lumen, shielding them from circulating ribonucleases, which would otherwise catalyze their degradation. However, there is an ongoing debate regarding the implication of miRNA contained within EVs in modulating biological activities on a molecular level. Therefore, the aim of the present review is to discuss the role of EV-derived miRNA, focusing on their implication in molecular mechanisms underlying atheroma formation. EVs of endothelial origin can regulate monocyte activation by transferring miR-10a that targets components of the inflammatory pathway. Tail vein administration of EVs derived from endothelial cells enriched in miR-34c-5p markedly reduces atherosclerosis progression. In patients with stable coronary artery disease, elevated levels of miR-126 and miR-199a in circulating EVs are significantly associated with a reduced incidence of major adverse cardiovascular event rate. These nanoparticles, released by all cells into most biological fluids, hold promise as a liquid biopsy tool as their circulating patterns and cargo can reflect the onset and severity of cardiovascular diseases.</p>","PeriodicalId":7623,"journal":{"name":"American Journal of Pathology","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145058223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"This Month in AJP","authors":"","doi":"10.1016/j.ajpath.2025.09.001","DOIUrl":"10.1016/j.ajpath.2025.09.001","url":null,"abstract":"","PeriodicalId":7623,"journal":{"name":"American Journal of Pathology","volume":"195 11","pages":"Page 1963"},"PeriodicalIF":3.6,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145038856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Aldehyde Dehydrogenase 2 Deficiency Impairs Liver Progenitor Cell Proliferation in Alcohol-Fed Mice.","authors":"Peng Xiao, Siting Yang, Shenghua Bi, Yawen Hao, Feiyu Zhang, Lin Ru, Tao Liu, Shengying Qian, Qiuhong Zai, Ningning Ma, Junqi Niu, Yong He, Yanhang Gao","doi":"10.1016/j.ajpath.2025.08.004","DOIUrl":"10.1016/j.ajpath.2025.08.004","url":null,"abstract":"<p><p>Aldehyde dehydrogenase 2 (ALDH2) is a critical enzyme involved in the detoxification of acetaldehyde. Although numerous studies have demonstrated the significance of ALDH2 in alcohol-associated liver disease, its role in alcohol-induced activation of liver progenitor cells (LPCs) has not been thoroughly investigated. Proteomic analysis of serum samples from patients with either normal ALDH2 genotype or ALDH2 mutation following alcohol consumption revealed that ALDH2 deficiency may suppress LPC proliferation. To test this hypothesis, Aldh2 knockout (Aldh2KO) mice were generated and fed a 3,5-diethoxycarbonyl1,4-dihydrocollidine-supplemented diet along with 10% ethanol in drinking water. A significant inhibition of LPC proliferation was observed in Aldh2KO mice after alcohol exposure, as indicated by reduced numbers of pan-cytokeratin (PanCK)- and Ki-67-positive cells in the liver. Bulk RNA sequencing revealed that differentially expressed genes (DEGs) in 3,5-diethoxycarbonyl1,4-dihydrocollidine plus ethanol-fed Aldh2KO mice were enriched in pathways related to inflammation (up-regulated DEGs) and cell cycle suppression (down-regulated DEGs) based on Reactome pathway analysis compared with wild-type mice. Mechanistically, alcohol exposure in Aldh2KO mice led to reduced LPC proliferation, likely mediated by enhanced hepatic pyroptosis and inflammatory responses. In conclusion, these findings suggest that ALDH2 deficiency appears to impair LPC proliferation in alcohol-associated liver disease, highlighting the critical role of ALDH2 in liver regeneration following alcohol-induced injury.</p>","PeriodicalId":7623,"journal":{"name":"American Journal of Pathology","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145005771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zoey K. Wallis , Yingshan Wei , Lily M. Ceraso , Cecily C. Midkiff , Addison Q. Amadeck , Yiwei Wang , Andrew D. Miller , Robert V. Blair , Kenneth C. Williams
{"title":"Novel Perineural Pathways and the Dynamics of SIV-Infected Macrophage Trafficking Out of the Central Nervous System","authors":"Zoey K. Wallis , Yingshan Wei , Lily M. Ceraso , Cecily C. Midkiff , Addison Q. Amadeck , Yiwei Wang , Andrew D. Miller , Robert V. Blair , Kenneth C. Williams","doi":"10.1016/j.ajpath.2025.07.014","DOIUrl":"10.1016/j.ajpath.2025.07.014","url":null,"abstract":"<div><div>A challenge to eradicate HIV is the central nervous system (CNS) reservoir and unknown mechanisms-pathways by which infected macrophages can exit. We used intracisternal injection of superparamagnetic iron oxide nanoparticles (SPIONs), some of which had different internal immune fluorescence to define perineural pathways of SPION<sup>+</sup> macrophage traffic in SIV-infected animals with AIDS, on antiretroviral therapy (ART) and with ART interruption. SPION<sup>+</sup> macrophages are identified in central (spinal cord and cranial nerves) and peripheral (dorsal root ganglia) sites. In noninfected animals, SPION<sup>+</sup> macrophages traffic out normally. With SIV infection, SPION<sup>+</sup> macrophages accumulate in the CNS, and there are decreased numbers that traffic out. SIV-RNA and SIV-glycoprotein 41 (gp41) SPION<sup>+</sup> macrophages are found in cranial nerves and dorsal root ganglion that are significantly reduced, but not eliminated, with ART. Using SPIONs with two different internal fluorescences, injected early and late after SIV infection, we find AIDS animals have greater numbers of early injected SPION<sup>+</sup> macrophages within cranial nerves, consistent with reduced traffic late. With ART, there are greater numbers of late and dual (early and late) labeled SPION<sup>+</sup> macrophages in the periphery, that return to levels found in AIDS animals following ART interruption. These findings reveal a novel pathway by which CNS macrophages can redistribute virus from the CNS to the periphery that persists despite ART.</div></div>","PeriodicalId":7623,"journal":{"name":"American Journal of Pathology","volume":"195 11","pages":"Pages 2233-2246"},"PeriodicalIF":3.6,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144999411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Sugar-Coated Truth of Alcohol-Associated Liver Disease: Galectins as Multifaceted Regulators of Alcohol-Induced Liver Injury.","authors":"Doug Terry, Brian S Robinson","doi":"10.1016/j.ajpath.2025.07.013","DOIUrl":"10.1016/j.ajpath.2025.07.013","url":null,"abstract":"<p><p>Alcohol-associated diver disease is a major driver of end-stage liver diseases globally. Alcohol functions as a hepatotoxin by overwhelming cell stress response pathways and deregulating hepatocellular protein, amino acid, and lipid metabolism. In addition, alcohol alters innate and adaptive inflammatory immune responses and acts on extrahepatic organs to flood the liver with pro-inflammatory stimuli. Here we examine how galectins, a class of highly conserved carbohydrate-binding proteins, regulate liver homeostasis and pathology. Next, we define how galectins affect key pathways that drive alcohol-induced liver disease, including hepatocyte cell biology (eg, altered lipid metabolism, endoplasmic reticulum and lysosomal stress, mitochondrial dysfunction), innate and immune response, intestinal dysfunction, and liver fibrosis. We then document the roles of galectins in the setting of alcohol-associated liver disease. Finally, we discuss galectins as theragnostic markers and therapeutic targets for alcohol-associated liver disease and address key open questions in the field.</p>","PeriodicalId":7623,"journal":{"name":"American Journal of Pathology","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144939071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Role of Perivascular Adipose Tissue, White Adipose Tissue, and Brown Adipose Tissue in the Pathophysiological Effects of Ethanol.","authors":"Thales M H Dourado, Carlos R Tirapelli","doi":"10.1016/j.ajpath.2025.07.012","DOIUrl":"10.1016/j.ajpath.2025.07.012","url":null,"abstract":"<p><p>Adipose tissue plays a crucial role in energy storage, but it also acts as an endocrine organ by secreting hormones and proinflammatory molecules. It regulates various processes, including adipogenesis, metabolism, and inflammation. White and brown adipose tissue (WAT and BAT) consists of white and brown adipocytes, respectively, which differ in cellular structure and function. Adipocytes also make up a significant part of perivascular adipose tissue (PVAT), which forms a sheath-like structure around blood vessels. Current research indicates that WAT, BAT, and PVAT are negatively affected by ethanol (ethyl alcohol). The changes induced by ethanol in the storage, metabolic, and secretory functions of PVAT and WAT are linked to vascular and hepatic dysfunction. In this context, while adipose tissue is a target of the harmful effects of ethanol, it also contributes to its pathophysiological consequences. Although the function of BAT is impacted by ethanol, BAT exhibits a protective role against ethanol-induced liver disease. This review highlights both past and recent efforts to identify the mechanisms through which ethanol consumption alters adipocyte function, with a focus on findings from studies that explain the detrimental effects of ethanol on WAT and BAT, and discusses the interplay between adipose tissue and the liver, particularly its implications for alcoholic liver disease. Additionally, new data that elucidate the mechanisms underlying ethanol-induced dysfunction in PVAT are summarized.</p>","PeriodicalId":7623,"journal":{"name":"American Journal of Pathology","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144939057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Proteostasis Network in Proteinopathies","authors":"Dariusz Pytel, Jody Fromm Longo","doi":"10.1016/j.ajpath.2025.07.011","DOIUrl":"10.1016/j.ajpath.2025.07.011","url":null,"abstract":"<div><div>Proteinopathies are neurodegenerative disorders that are characterized by accumulation of misfolded toxic protein aggregates that lead to synaptic and neuronal dysfunction. Although genetically, clinically, and pathologically distinct, a common feature of these diseases is disruption of protein homeostasis (proteostasis), which causes accumulation of misfolded proteins. The machinery mediating proteostasis exquisitely balances and interlaces protein synthesis, protein folding and trafficking, and protein degradation processes within the proteostasis network to maintain homeostasis. The proteostasis network governs a functional and dynamic proteome by modulating the timing, location, and stoichiometry of protein expression, surveillance, and maintenance of protein folding and removal of misfolded or excess proteins. Although a functional proteome is essential for the health of all cell types, this is especially true for neurons, which are prone to enhanced cellular stress. Aging is the most important risk factor for proteostasis decline and the development of proteinopathies. However, germline and somatic mutations can also functionally impair components of the proteostasis network. Post-mitotic cells, particularly neurons, are rendered further susceptible to proteostasis dysfunction because of their extended lifespan. This review discusses the interconnections between the functional components mediating proteostasis in neuronal cells and how aberrations in proteostasis contribute to neuronal dysfunction and disease.</div></div>","PeriodicalId":7623,"journal":{"name":"American Journal of Pathology","volume":"195 11","pages":"Pages 1998-2014"},"PeriodicalIF":3.6,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144938985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Delia Y Omar, Mathilda M Willoughby, Nourhan Mostafa, Kelly Otakhor, Saumya Bhatt, Mohammad A Abbas Zaidi, Micah B Schott
{"title":"Lipid Droplet Dynamics in Alcoholic Steatohepatitis.","authors":"Delia Y Omar, Mathilda M Willoughby, Nourhan Mostafa, Kelly Otakhor, Saumya Bhatt, Mohammad A Abbas Zaidi, Micah B Schott","doi":"10.1016/j.ajpath.2025.07.010","DOIUrl":"10.1016/j.ajpath.2025.07.010","url":null,"abstract":"<p><p>Alcohol-associated liver disease poses a significant global health burden, with alcoholic steatohepatitis (ASH) representing a severe subtype driven by chronic alcohol consumption, hepatic inflammation, and limited treatment options. Central to ASH pathogenesis is the dysregulation of lipid droplet (LD) dynamics in hepatocytes. This review explores the critical role of LDs, focusing on alcohol-induced disruptions in LD biogenesis and catabolism. Chronic ethanol exposure enhances LD biogenesis from lipid import and de novo lipogenesis, while impairing LD catabolism by inhibiting lipolysis and lipophagy. Also, the review article examines alcohol's effect on remodeling the LD proteome and lipidome, including post-translational modifications. Additionally, LDs emerge as morphologic markers in hepatic stellate cells, where their loss drives fibrosis. Recent advances highlight potential therapeutic targets, such as restoring lipophagy or modulating LD biogenesis, offering hope for effective ASH treatments. This review underlines LDs as pivotal organelles in ASH progression and therapeutic innovation.</p>","PeriodicalId":7623,"journal":{"name":"American Journal of Pathology","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144939040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Navigating the Road to Progress in Neurodegeneration","authors":"Yomna Badawi , Christi L. Kolarcik","doi":"10.1016/j.ajpath.2025.02.010","DOIUrl":"10.1016/j.ajpath.2025.02.010","url":null,"abstract":"","PeriodicalId":7623,"journal":{"name":"American Journal of Pathology","volume":"195 9","pages":"Pages 1572-1574"},"PeriodicalIF":3.6,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}