Histology and histopathology最新文献

Background: 1,25-Dihydroxyvitamin D3 (1,25(OH)₂D₃) is a physiologically active form of vitamin D. Our study investigated the renoprotective functions of 1,25(OH)₂D₃ in diabetic nephropathy (DN) progression and its underlying mechanism targeting the ROS/TXNIP/NLRP3 inflammasome pathway.

Methods: DN was induced in Wistar rats via high-fat diet (4 weeks) and streptozotocin injection (30 mg/kg, i.p.); hyperglycemic rats were randomized into DN and DN + 1,25(OH)₂D₃ (16 μg/kg, 12 weeks) groups. Rat mesangial HBZY-1 cells were maintained under normal glucose (5.5 mM), high glucose (25 mM), high glucose plus 1,25(OH)₂D₃ (1-50 nM), or high glucose plus N-acetylcysteine (NAC, 10 mM). Cell viability was assessed by the CCK-8 assay. Oxidative stress parameters (ROS via DCFH-DA fluorescence, MDA content, SOD activity) and pyroptosis markers (LDH release, PI/Hoechst 33342 nuclear staining) were quantified. Renal histopathology was performed using PAS and Masson trichrome staining. Biochemical analyses included serum creatinine, urea nitrogen, and 24-h urinary protein quantification. Molecular profiling encompassed ELISA (IL-1β, IL-6, TNF-α, IL-18, fibronectin, collagen IV), RT-qPCR (NOX2, NOX4, NLRP3, ASC), western blotting (TXNIP, NLRP3, ASC, caspase-1, IL-1β, IL-18, collagen IV, fibronectin, laminin), and TXNIP immunofluorescence.

Results: 1,25(OH)₂D₃ significantly attenuated high glucose-induced pathological alterations in HBZY-1 cells, including ROS overproduction, TXNIP upregulation, NLRP3 inflammasome activation, oxidative stress, inflammation, extracellular matrix (ECM) deposition, and pyroptotic cell death. Consistently, 1,25(OH)₂D₃ suppressed ROS/TXNIP/NLRP3/caspase-1 signaling, ameliorated renal dysfunction, and mitigated histopathological damage in DN rats.

Conclusion: 1,25(OH)₂D₃ confers renoprotection in DN by inhibiting the ROS/TXNIP/NLRP3 inflammasome axis, thereby suppressing oxidative stress, inflammatory cytokine production, ECM accumulation, and pyroptotic cell death in glomerular mesangial cells and renal tissues.

Background: Myocardial ischemia/reperfusion (MI/R) injury may cause serious arrhythmia and even sudden death. Sirtuin 2 (SIRT2) belongs to NAD (+) dependent class III histone deacetylase. The present study explored the potential mechanism of SIRT2 in MI/R injury.

Methods: A rat model with MI/R injury was established. Differentially expressed genes in myocardial tissues of MI/R-treated rats and sham-operated rats were analyzed by microarray. The AAV9-encapsulated SIRT2 overexpression vector was injected into rats to evaluate the effect of SIRT2 on MI/R injury. Oxygen glucose deprivation/reoxygenation (OGD/R) treatment was used to simulate MI/R injury at a cellular level. SIRT2 overexpression vector was transfected into cardiomyocytes. The expression of forkhead box O3 (FOXO3), a potential transcription factor predicted to bind to SIRT2, was detected in myocardial tissues of modeled rats and OGD/R-treated cardiomyocytes. The effect of FOXO3 on OGD/R-treated cardiomyocytes was confirmed by functional rescue experiments. The expressions of NLRP3 and caspase1 were detected.

Results: SIRT2 was downregulated in myocardial tissues of MI/R-treated rats. Overexpression of SIRT2 alleviated MI/R injury in modeled rats and enhanced viability of OGD/R-treated cardiomyocytes. FOXO3 activated SIRT2 transcription and expression. FOXO3 was downregulated in the myocardial tissues of MI/R-treated rats and OGD/R-treated cardiomyocytes. Knockdown of FOXO3 weakened the effects of SIRT2 on MI/R injury. SIRT2 reduced MI/R injury by inhibiting NLPR3/caspase1 inflammasome signaling.

Conclusion: FOXO3 activates SIRT2 expression and inhibits NLPR3 inflammasome signaling pathway, thus alleviating MI/R injury. This study may offer a novel molecular target for the management of MI/R injury.

Intraductal carcinoma of the prostate (IDC-P) is characterized by neoplastic cell proliferation within pre-existing ducts or acini, exhibiting architectural and cytological atypia exceeding that of high-grade prostatic intraepithelial neoplasia. Its presence in needle biopsies and prostatectomies is associated with adverse clinical and pathological features, including large tumor volume, high grade, advanced stage, early biochemical recurrence, and intrinsic resistance to systemic therapy. Although rare, IDC-P can occasionally occur without concurrent invasive cancer or be associated with low-grade prostate cancer. Molecularly, IDC-P resembles its associated invasive carcinoma, sharing alterations typical of high-grade aggressive tumors. These findings support the hypothesis that IDC-P arises from the retrograde spread of invasive carcinoma, with ducts providing a protective niche against the tumor microenvironment. In contrast, isolated IDC-P and IDC-P associated with low-grade invasive carcinoma may represent precursor lesions. IDC-P must be distinguished from other intraductal lesions, both benign and malignant, particularly in needle biopsies, as its detection impacts therapeutic decisions. While grading does not apply to isolated IDC-P, there is an ongoing debate regarding IDC-P with synchronous invasive cancer. The International Society of Urological Pathology (2019) recommends incorporating IDC-P into Gleason score calculations, whereas the Genitourinary Pathology Society advises against grading it at all. Both approaches have merit, but further validation studies focusing on cases where IDC-P inclusion alters the final grade, though uncommon, are warranted.

Limb-girdle muscular dystrophy (LGMD) is a genetically heterogeneous group of muscle disorders characterized by progressive muscle atrophy and loss of motor function. Over 30 subtypes have been identified and classified into two main inheritance patterns: autosomal dominant and autosomal recessive. Besides primarily affecting skeletal muscle, certain subtypes also impact the cardiac and respiratory muscles, significantly influencing disease progression and patient survival. Substantial progress has been made in understanding the pathogenic genes and molecular mechanisms of LGMD; however, developing disease-modifying therapies remains challenging due to genetic heterogeneity, limitations in gene delivery technologies, and secondary pathological complications. Current treatments are primarily supportive, focusing on symptom management and improving quality of life rather than addressing the underlying cause. This paper summarizes recent advances in LGMD pathogenesis and emerging therapeutic strategies, highlighting progress and remaining challenges in the field.

Melanocytic neoplasms range from benign nevi to malignant melanomas, and accurate differentiation between these lesions is crucial for effective treatment. Among the various immunohistochemical markers available, PRAME (Preferentially Expressed Antigen in Melanoma) has emerged as a significant diagnostic tool in the evaluation of melanocytic lesions due to its high sensitivity and specificity, particularly in distinguishing malignant melanomas from benign nevi. PRAME is strongly expressed in malignant melanomas, including cutaneous, uveal, and mucosal variants, while its expression is minimal or absent in benign and dysplastic nevi. Its utility extends to identifying metastases, especially in difficult-to-diagnose cases such as metastatic melanoma, where it aids in differentiating melanoma from other malignancies. Additionally, the presence of PRAME is associated with poor prognosis, as higher expression levels correlate with increased metastatic risk. Despite its effectiveness, the use of PRAME in immunohistochemistry is not without limitations. It is not exclusive to melanoma, as its expression can be seen in some non-melanocytic tumors, which may reduce its specificity in certain cases. Nevertheless, PRAME remains a valuable tool in the diagnostic and prognostic evaluation of melanocytic lesions, particularly when histological features are unclear or ambiguous. Further research is needed to refine its role in different melanoma subtypes and to explore its potential as a target for immunotherapy.

Objectives: As a surgical option for osteochondral lesions of the talus, autologous matrix-induced chondrogenesis (AMIC^®) combines bone marrow stimulation, filling of subchondral defects, and application of a collagen bilayer matrix. The purpose of the study was to analyze the cartilage at the treated defect site in two patients.

Methods: Two patients underwent revision surgery (14 and 36 months after the index AMIC^® procedure) for failure due to ligamentous instability. During revision, the repair cartilage was evaluated regarding its integration, presence of fissures, thinning, or firmness. Samples for histologic evaluation were taken from the centre of the treated site. The samples were examined using standard histological and immunohistochemistry techniques.

Results: During the revision arthroscopy, the regenerated cartilage was the same color but softer than the surrounding cartilage, superficially frayed, without fissures and even with the level of the original cartilage, but not completely stable on the subchondral bone. Histology revealed the presence of Safranin-O-positive fibrocartilage-like tissue. Additionally, cartilaginous-like tissue was found in the 36-month biopsy. IHC revealed a fraction of collagen type II positive cells in the fibrocartilage-like tissue as well as a collagen type II positive extracellular matrix. The cartilaginous tissue of the 36-month biopsy revealed a homogeneous collagen type II stain.

Conclusions: The presence of collagen type II within the tissue indicates its transformation into hyaline-like cartilage at 14 months after AMIC^® continuing up to 36 months. While second-look arthroscopies and histological analyses are rare, the data presented here demonstrate cartilage regeneration, with a progressive formation of a hyaline-like cartilaginous tissue in the talus after AMIC^®.

Sepsis is a major cause of acute kidney injury (AKI). Dysregulation of N7-methyladenosine (m7G) methylation is a pathogenic mechanism of sepsis. However, the role of m7G methylation in renal damage remains poorly understood. In this study, we investigated the regulation of METTL1, an m7G writer, on pyroptosis in sepsis-induced AKI. HK-2 cells were treated with lipopolysaccharide (LPS), and pyroptosis was assessed using enzyme-linked immunosorbent assays and western blotting. The m7G methylation status of NLRP3 was analyzed through methylated-RNA immunoprecipitation (Me-RIP), RNA immunoprecipitation (RIP), and dual-luciferase reporter assays. Renal injury in mice subjected to cecal ligation and puncture (CLP) was evaluated using hematoxylin and eosin (H&E) staining. Our results demonstrated that METTL1 expression was significantly upregulated in both LPS-treated HK-2 cells and the CLP-induced mouse model. Interfering with METTL1 suppressed LPS-induced pyroptosis in vitro and attenuated kidney damage and pyroptosis in vivo. Furthermore, METTL1 knockdown inhibited m7G methylation of NLRP3, thereby reducing its stability. Overexpression of NLRP3 abrogated the inhibition of pyroptosis caused by METTL1 knockdown. In conclusion, silencing of METTL1 alleviates sepsis-induced AKI by inhibiting m7G methylated NLRP3-mediated pyroptosis in renal tubular epithelial cells. These findings suggest that targeting METTL1 may represent a promising therapeutic strategy for managing sepsis-associated AKI.

Glucocorticoid receptor (GR) has been implicated in prostate carcinoma and possibly involved in cancer growth and progression. Therefore, in this study, we examined whether the genes involved in cell proliferation regulation were induced by cortisol in androgen-independent human prostate cancer DU145 cells. Gene expression profiling of the DU145 cell pathway was conducted using the RT² Profile PCR Array System, quantitative reverse transcriptase polymerase chain reaction, and immunoblot analysis. These analyses demonstrated that the expression level of Period 1 (PER1), a gene associated with an organism's biological clock and involved in anti-apoptosis and cell growth, was markedly increased in DU145 cells treated with dexamethasone (DEX). In addition, analysis using short hairpin RNA demonstrated that products of PER1 were involved in the DEX-induced proliferation of DU145 cells. Therefore, PER1 is considered a glucocorticoid-responsive gene that regulates DU145 cell proliferation induced by GR stimulation, thus potentially playing an important role in GR-related androgen-independent human prostate cancer.

Aims: To investigate the diagnostic value of Interferon regulatory factor 8 (IRF8) in blastic plasmacytoid dendritic cell neoplasm (BPDCN) and extranodal NK/T-cell lymphoma, nasal type (ENKTL).

Methods: Immunohistochemistry staining was used to detect IRF8 expression in 19 cases of BPDCN and 59 cases of ENKTL. In addition, 21 cases of myeloid sarcoma, 30 of B-lymphoblastic leukemia/lymphoma (B-ALL/LBL), 30 of T-lymphoblastic leukemia/lymphoma (T-ALL/LBL), 10 of histiocytic sarcoma, 10 of Langerhans cell histiocytosis, and 9 of follicular dendritic cell sarcoma were also included. DNA sequencing detected IRF8 genetic variation in 6 cases of BPDCN and 20 cases of ENKTL.

Results: IRF8 expression was detected in 100.00% (19/19) of BPDCN, exhibiting a strong and uniform staining pattern, and in 91.53% (54/59) of ENKTL, with varying degrees of staining intensity. Weak and focal staining was detected in 33.33% (7/21) of myeloid sarcoma, 13.33% (4/30) of B-ALL/LBL, and 11.11% (1/9) of follicular dendritic cell sarcoma. No expression was found in T-ALL/LBL, histiocytic sarcoma, or Langerhans cell histiocytosis. The proportion of IRF8 positive expression was higher in BPDCN and ENKTL than in other hematolymphoid neoplasms. In ENKTL, the average IRF8 expression was higher in nasal cases than in extranasal cases and in cases with mitosis figures of more than 4/10 high-power field (HPF). Predominantly large transformed cell morphology and extranasal involvement site might serve as independent prognostic factors of two-year survival in ENKTL. IRF8 genetic point mutations were found in 33.33% (2/6) of BPDCN and 10.00% (2/20) of ENKTL.

Conclusion: The study demonstrated the promising value of IRF8 in the diagnosis of BPDCN and ENKTL.

Objective: Myocardial ischemia/reperfusion injury (MIRI) is a life-threatening event that typically follows reperfusion therapy for myocardial infarction. Regarding the effects of dexmedetomidine (Dex) in MIRI, we explored its specific mechanism.

Methods: The MIRI rat model was treated with Dex, Topotecan [a hypoxia-inducible factor-1α (HIF-1α) inhibitor], and lentiviral-overexpressing FUN14 domain-containing protein 1 (Lv-oe-FUNDC1), with rat heart rate analysis. The pathological damage of rat myocardial tissue was evaluated by hematoxylin-eosin (HE) and Masson staining. Positive expression levels of PTEN-induced kinase 1 (PINK1), Parkin, microtubule-associated protein 1 light chain 3 (LC3) II/I, p62 and Beclin1 proteins, HIF-1α and FUNDC1 messenger RNA (mRNA), and HIF-1α and FUNDC1 were assessed by western blot, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and immunohistochemical staining, respectively. HIF-1α-FUNDC1 binding sites and targeted binding relationships were predicted and verified via databases and dual-luciferase assay. HIF-1α enrichment levels in the FUNDC1 promoter region were evaluated using a ChIP assay.

Results: MIRI rats exhibited myocardial injury and severe myocardial dysfunction, with elevated left ventricular diastolic pressure and p62 expression, reduced left ventricular systolic pressure, and maximum rate of change in left ventricular pressure and PINK1, Parkin, LC3 II/I ratio and Beclin-1 protein levels, which were reversed by Dex treatment. MIRI rats had increased HIF-1α and FUNDC1 expression levels, which were further boosted after Dex treatment. Dex promoted mitophagy to ameliorate myocardial injury in MIRI rats via the HIF-1α/FUNDC1 axis.

Conclusion: Dex promoted mitophagy by up-regulating HIF-1α to facilitate the transcriptional expression of FUNDC1, thereby ameliorating myocardial injury in MIRI rats.