Histology and histopathology最新文献

Knowledge regarding the biology of the nervous system and its functions has gone through various theoretical, methodological, and interpretative stages throughout history, depending largely on technical advances that have allowed us not only to approach old questions from new perspectives but also to address new ones. One advance that constituted a watershed in the history of neuroscience was the appearance of a chrome-silver staining technique called the Golgi method that allowed the complete, three-dimensional observation of nerve cells. Discovered by Camilo Golgi and, later, modified significantly and employed by Santiago Ramón y Cajal, Golgi's method was crucial in demonstrating the veracity of the Neuronal Theory over the earlier Reticular Theory, and in revealing numerous findings related to the human brain and those of many other animal species, which continue to be analyzed today. Despite a period of scientific recession in the first half of the 20^th century, the use of the Golgi method prevailed and even expanded in the second half of that century and into the 21^st, as researchers continued to use it in its original or modified form and in combination with emerging methodologies. Currently, there are no signs of any decline in its use.

Background and objective: From a clinical standpoint, myocardial ischemia/reperfusion injury (MIRI) has always been an enormous challenge for the treatment of acute myocardial infarction (AMI). Molecular targeting therapy may help overcome this challenge. The present work aimed to elucidate the possible involvement of Yin-Yang 1 (YY1)/nuclear receptor-interacting protein 1 (NRIP1) and discover the molecular mechanism of MIRI.

Methods: Herein, a cardiomyocyte ischemia/reperfusion (I/R) model was established via oxygen-glucose deprivation/re-oxygenation (OGD/R) damage in H9c2 cardiomyocytes. Reverse transcription-quantitative PCR and western blotting were conducted to measure the levels of YY1 and NRIP1 at the RNA and protein levels, respectively. H9c2 cell viability and apoptosis were assayed using the Cell Counting Kit-8, flow cytometry, and western blotting. In addition, superoxide dismutase, glutathione peroxidase, and malondialdehyde levels were analyzed as markers of oxidative stress. Additionally, mitochondrial membrane potential, which was measured via JC-1 staining, ATP content, Complex I activity, mitochondrial DNA copy number, and mitochondrial permeability transition pore (mPTP) opening rate were analyzed to evaluate mitochondrial activity. Moreover, luciferase reporter and chromatin immunoprecipitation assays experimentally validated the predicted affinity of YY1 with the NRIP1 promoter according to the HumanTFDB online tool.

Results: YY1/NRIP1 were both highly expressed in OGD/R-injured H9c2 cardiomyocytes. Downregulation of NRIP1 improved cell viability, whereas it inhibited cell apoptosis and oxidative stress, and suppressed mitochondrial dysfunction in OGD/R-injured H9c2 cardiomyocytes. Importantly, it was verified that YY1 could bind to the NRIP1 promoter to positively regulate NRIP1 expression. The protective effects of NRIP1 knockdown against cardiomyocyte damage and mitochondrial dysfunction in OGD/R-injured H9c2 cardiomyocytes were partly abolished through overexpression of YY1.

Conclusion: NRIP1 emerged as a downstream target of YY1 in promoting OGD/R-induced H9c2 cardiomyocyte injury and mitochondrial dysfunction, providing novel ideas for targeted treatments to alleviate MIRI.

Background: The aim of this study was to evaluate the morphology (atrophy and fibrosis), apopto-sis, and cell proliferation in the uterine wall. The research material came from postmenopausal women who had undergone hysterectomy due to uterine myomas or prolapse of the reproductive organ and were not taking menopausal hormone therapy (MTH).

Material and methods: The collected material was divided into three groups. Group I (n=18) con-sisted of uterine sections taken 1 to 5 years after the last menstruation, Group II (n=17) 6 to 10 years after the last menstruation, and Group III (n=15) over 11 years after the last menstruation. To assess morphology and fibrosis, the uterine sections were subjected to hematoxylin and eosin (HE) staining and to Mallory's staining. In addition, we performed a histochemical examination to identify apopto-sis in endometrial and myometrial cells using the TUNEL method. An immunohistochemical analysis of endometrial and myometrial cells was also performed to detect the location of the proliferating cell nuclear antigen (PCNA).

Results: Differences in apoptosis were only found in the myometrium between Group I and Group III, and were strongest in Group I myometrial cells, and weakest in Group III. Neither the endome-trium nor the myometrium showed statistically significant differences in the overall percentage of PCNA(+) cells between groups.

Conclusion: Morphological changes in the endometrial and myometrial layers of postmenopausal uteri increased with time since the last menstruation.

Natural killer (NK) cells are the promoters in graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT), while demethylation can regulate NK cell function. We explored the mechanism of demethylation regulating NK cell function to affect GVHD after allo-HSCT. BALB/c mice were transfused with C57BL/6 mouse-derived NK and bone marrow cells to establish GVHD models, followed by isolation and in-vitro expansion of NK cells. NK cell purity, cytokine levels, proliferation, and cytokine-producing NK cell levels were measured via flow cytometry. KIR2DL1/2/3 methylation was tested by Methylation-specific polymerase chain reaction (MSP), with determination of mouse survival and GVHD scores. KIR2DL1/2/3 and DNMT1 expression was detected through qRT-PCR and/or western blot. Methylation levels were upregulated and KIR2DL1/2/3 expression was downregulated in GVHD mouse model-derived NK cells following IL-2 stimulation. DNMT1 silencing promoted KIR2DL1/2/3 expression, proliferation, and the secretion of Granzyme, Perforin, and Interferon-γ (IFN-γ) in C57BL/6 mouse-derived NK cells. DNMT1 silencing also enhanced mouse survival, reduced GVHD scores, promoted KIR2DL1/2/3 expression on the NK cell surface, and increased the secretion of Granzyme, Perforin, IFN-γ, and the number of cytokine-producing NK cells in the spleen, liver, and lung tissues of the models. Collectively, DNMT1 silencing induced KIR2DL1/2/3 expression in NK cells through reducing methylation to alleviate GVHD after allo-HSCT.

The lamina propria (LP) of the urinary bladder lies between the urothelial mucosa and the muscularis propria. This complex stratum is composed of extracellular matrix, several cell types, and collagen types I and III fibers. LP invasion by urothelial carcinoma (progression from stage Ta to T1) is a determinant of bladder cancer advancement. We attempted to characterize collagen fiber arrangement in the LP. This could enrich our understanding of this important layer and potentially provide clues for sub-staging of the T1 bladder cancer. A total of 24 Masson trichrome-stained images of normal bladder, including 12,530 collagen fibers were quantitatively analyzed using the Dragonfly software. The LP was divided according to fiber orientation into superficial LP (SLP, 15% of the thickness) and the deep LP (DLP, 85% of the thickness). Collagen fiber geometry analysis demonstrated that the SLP fibers are more parallel to the urothelium with an average angle of 26⁰±23⁰ compared to 40⁰±26⁰ in the DLP (p=3.4X10^-144), more packed (average distance to the closest fiber of 0.61±0.67 compared to 0.66±0.77, p=0.0001), and their aspect ratio is considerably longer (average of 1.93±0.12 compared to 0.20±0.11, p=2.84x10^-8). No difference was found in fiber perimeter or Feret diameter. Thus, we conclude that bladder collagen fibers are arranged in two distinct layers: a dense-ordered SLP and a loose disorder DLP. This indicates that the physical barrier to cancer cell invasion probably lies in the SLP, immediately underneath the urothelium. Once this barrier is breached, the looser and disorganized DLP poses no remarkable obstacle. Thus, we believe that histology-based subdivisions of stage T1 are expected to fail in providing clinically meaningful prognostic information.

Background: Hepatic fibrosis, ultimately causing hepatic sclerosis, remains significant health concerns. Adipose-derived mesenchymal stem cell (ADMSC)-derived exosomes (Exo) exhibit amelioration of liver injury. Hepatocyte growth factor (HGF) regulates hepatocyte growthn. However, its involvement during hepatic fibrosis remains unclear.

Methods: Isolation of ADMSCs and Exo, transfection of HGF overexpression, and activation of hepatic stellate cells (HSCs) by Angiotensin II (AngII) were conducted. Cells were randomized into HSC, AngII-HSC, ADMSCs-Exo, ADMSCs-Exo, and ADMSCs^HGFblank-Exo, and ADMSCs^HGF-Exo groups (n=6). HE, Sirius red, and Oil Red O staining, liver function indicators, and ELISA for oxidative stress were performed. ROS generation-related and PI3K/Akt/P38MAPK-related factors were detected by immunofluorescence, immunohistochemistry, and western blot.

Results: After identification of ADMSC-Exo and transfection, AngII increased cell viability, migration, Collagen I (CoLI), α-smooth muscle actin (α-SMA), ROS, NADPH oxidase 4 (NOX4), PI3K, p-Akt, p-P38MAPK, ras-related C3 botulinum toxin substrate 1 (RAC1), p47^phox, and p22^phox expression. However, ADMSCs^HGF-Exo, DPI, LY294002, and SB203580 reversed the above effects. Moreover, ADMSCs^HGF-Exo inhibited pathological damage, fibrosis, lipid accumulation, ALT, AST, TBIL, CoLI, α-SMA, NOX4, MDA, PI3K, p-Akt, and p-P38MAPK expression, and increased ALB, SOD, GPx, CAT, GSH, Mn-SOD, Na⁺-K⁺-ATPase, and Ca²⁺-Mg²⁺-ATPase levels in hepatic fibrosis mice.

Conclusion: ADMSCs^HGF-Exo attenuated hepatic fibrosis by inhibiting oxidative stress through activating the PI3K/Akt/P38MAPK pathway, providing valuable insights for potential treatment of liver fibrosis.

The skin forms the external covering of the body and is its largest organ, comprising many different cell types. Although the diversity of these cells has been widely studied with various histological methods, our understanding of skin architecture is mainly established on thin tissue sections, which restricted the information available to two dimensions. The development of innovative techniques to induce optical transparency ("clearing") in biological tissues has enabled researchers to visualize the three-dimensional reconstruction of intact organs and thick tissue sections at a cellular resolution. With the aid of tissue-clearing treatment, the labeled cutaneous nerve fibers and blood vessels can be followed for a longer distance on the thicker skin section or the whole mount skin under a fluorescence microscopy or a confocal microscopy. It is beneficial for demonstrating the morphological characteristics of nerve fibers and blood vessels themselves, as well as their spatial interconnection. In this review, we provide a brief summary of the literature on the use of tissue optical clearing methods and describe our experience of multiple fluorescent staining and tissue clearing approaches on thicker skin sections and whole-mount skin in our laboratory. Given the existing conventional methods, we expected to provide a more effective approach to comprehensively study skin architecture.

Background: Sarcopenia is a common age-related disease. Melatonin (MEL) is an age-related endocrine hormone, which displays a crucial role in resisting oxidative stress during aging. Importantly, the antioxidant properties of MEL can be mediated by mitochondria.

Objective: Therefore, we wondered whether MEL could mitigate oxidative stress caused by mitochondria in sarcopenia.

Methods: The middle-aged mice were administered 5 mg/kg/d and 10 mg/kg/d of MEL for 2 months. Young mice were used as the control group.

Results: After treatment with MEL, the grip strength of the fore/hind limbs, running time, and distance were elevated, and the weights of the gastrocnemius (GA), tibialis anterior (TA), extensor digitorum longus (EDL), and soleus (SOL) were enhanced in middle-aged mice. Additionally, MEL was observed to alleviate histological damage and increase the cross-sectional area of muscle fibers in GA tissues of middle-aged mice. Furthermore, following MEL treatment, there was an increase in the percentage and size of normal mitochondria as well as mtDNA copy number but a reduction in the levels of malondialdehyde (MDA), protein carbonyl, and reactive oxygen species (ROS) in the GA tissues of middle-aged mice. At the molecular level, MEL repressed the levels of ATROGIN-1, muscle RING-finger protein-1 (MURF-1), and the ratio of p-P38/P38, but elevated the expression of cytochrome c oxidase subunit 4 (COX4), cystatin C (CYTC), nuclear respiratory factor 1 (NRF-1), mitochondrial transcription factor A (TFAM), and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) in the GA tissues of middle-aged mice. Importantly, 10 mg/kg MEL was more efficacious in the treatment of sarcopenia than 5 mg/kg MEL.

Conclusion: MEL attenuates sarcopenia in middle-aged mice, and the mechanism may relate to mitochondria-induced oxidative stress and the PGC-1α/TFAM pathway.

Background: Intervertebral disc (IVD) degeneration (IVDD) is characterized by structural destruction accompanied by accelerated signs of aging. This study aimed to investigate the mechanism of lysine methyltransferase 2D (KMT2D) in the proliferation, apoptosis, and inflammation of nucleus pulposus cells (NPCs) in IVDD.

Methods: Mouse-derived NPCs were cultured and induced with interleukin-1 beta (IL-1β) to establish cell models. KMT2D expression was detected by western blot and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). KMT2D expression was interfered with, and the contents of IL-18, IL-6, and tumor necrosis factor (TNF) were detected by enzyme-linked immunosorbent assay. Cell proliferation, apoptosis, and the expression of miR-133a-5p and 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2 (PFKFB2) were measured. The enrichment of KMT2D and Histone 3 Lysine 4 monomethylation/dimethylation (H3K4me1/2) on the miR-133a-5p promoter was analyzed by chromatin immunoprecipitation and qPCR. The binding of miR-133a-5p and PFKFB2 was analyzed by a dual-luciferase assay.

Results: IL-1β treatment promoted KMT2D expression in NPCs. KMT2D knockdown reduced inflammation and apoptosis and promoted the proliferation of IL-1β-induced NPCs. Mechanistically, KMT2D upregulated miR-133a-5p expression by increasing the level of H3K4me2 at the miR-133a-5p promoter, thereby promoting the binding between miR-133a-5p and PFKFB2 and downregulating the transcription of PFKFB2. miR-133a-5p overexpression or PFKFB2 knockdown alleviated the protective effect of KMT2D knockdown on IL-1β-induced NPCs.

Conclusion: KMT2D promoted miR-133a-5p expression through H3K4me2 methylation, thereby promoting the binding of miR-133a-5p to PFKFB2, reducing the mRNA level of PFKFB2, promoting inflammation and apoptosis of IL-1β-induced NPCs, and inhibiting NPC proliferation.

Background: Gastric cancer (GC) is a predominant health concern in many countries. Actin-binding Rho activating C-terminal-like (ABRACL) belongs to a new family of low molecular weight proteins and has been implicated in cancers. This study was implemented to elucidate the role and mechanism of ABRACL in GC.

Methods: mRNA and protein expression of ABRACL and CBX4 in human gastric epithelium cell line GES-1 and GC cell lines were assessed with RT-qPCR and western blot. The transfection efficacy of sh-ABRACL, oe-CBX4, and sh-CBX4 was examined with RT-qPCR and western blot. AGS cell proliferation, migration, and invasion were evaluated using CCK-8, colony formation assay, wound healing, and Transwell assays, respectively. With western blot analysis, flow cytometry, and caspase-3 assay kits, the expressions of MMP2 and MMP9, cell apoptosis, and caspase-3 activity were estimated. Western blot was adopted to estimate the contents of apoptosis-related proteins. Luciferase reporter and chromatin immunoprecipitation (ChIP) were applied to verify the interaction between ABRACL and CBX4.

Results: The expression of ABRACL and CBX4 was increased in GC tissues and cells. After interfering with ABRACL, the proliferation, migration, and invasion of GC cells were inhibited while apoptosis was promoted. We also discovered that CBX4 could bind to ABRACL and transcriptionally regulate ABRACL expression in AGS cells. Rescue experiments revealed that CBX4 overexpression partially reversed the regulatory effects of ABRACL silencing on the proliferation, migration, invasion, and apoptosis of GC cells.

Conclusion: Collectively, ABRACL transcriptionally upregulated by CBX4 promoted the malignant progression of GC.