Cells Tissues Organs最新文献

Introduction: Fibrous connections between the suboccipital muscles and the spinal dura mater (DM), known as myodural bridges (MBs), have been extensively described in adults, but their embryological development and morphogenesis remain incompletely understood. This study examines the development of these structures, along with the posterior atlanto-occipital and atlanto-axial membranes (AOM and AAM), in human fetuses, to clarify their origin and potential functional relevance.

Methods: This study examined the histological sections of 40 human embryos and fetuses from 8 to 14 weeks of development (WD). The used sample belongs to the collection of the department of anatomy and embryology of the Complutense University of Madrid and was examined under light microscopy.

Results: At 8 WD, the DM, AOM, and AAM formed a common mesenchymal anlage, while the ligamentum nuchae (LN) developed separately. At 9 WD, the common anlage differentiated into DM and AOM-AAM. By 10 WD, the DM and AAM separated, forming the epidural space and allowing the establishment of connective tissue junctions. Between weeks 11 and 12 WD, the lower third of the AOM became continuous with the DM, forming a "fibrous intersection" composed of the DM, AOM, rectus capitis posterior minor (RMI), and LN. Between 13 and 14 WD, the DM thickened through the incorporation of connective fibers from the AOM, AAM, RMI, rectus capitis posterior major (RMA), obliquus capitis inferior (OCI), and LN.

Conclusion: This study shows that dense, regular fibrous connective tissue connections integrate into the DM originated from the AOM, AAM, RMI, RMA, OCI, and LN. The MB may help prevent dural infolding during upper cervical extension, as previously suggested, and the LN-DM junction could be a pathway used by veins to drain the epidural venous plexus. In our opinion, head movements and these connections would facilitate venous return.

Introduction: Innate lymphoid cells (ILCs) play a crucial role in immunity by regulating innate and adaptive immune cells and are involved in various physiological processes such as morphogenesis, homeostasis, metabolism, and tissue repair. ILCs are categorized into three primary subgroups: ILC1s, ILC2s, and ILC3s, which are distinguished by their functions and their production of cytokines resembling those of T helper cell subsets. The distribution of ILCs during development, particularly in rats, is not well understood. This study aimed to investigate the changes in tissue-specific ILC populations throughout rat development from embryonic days to postnatal day (PN) 30.

Methods: ILC subsets in different organs, such as the liver, lung, spleen, mesenteric lymph nodes (mLN), thymus, small intestine, and colon, were examined through surface and intracellular staining using flow cytometry (FACSAria III).

Results: In the liver, ILC3s were most common before birth, followed by an increase in ILC1s 1 week after birth and a rise in ILC2s by the end of the first month after birth. The lung showed an increase in ILC1s and NK progenitor cells after birth, with a decrease in ILC3s by the end of the first month postnatally. The spleen changed from being dominated by ILC3s in the fetal period to being dominated by ILC2s at PN30. In the mLN, ILC2s were the most common subtype throughout development. ILC3s were the main subtype in the thymus, with a decrease in NK cell representation after birth. The small intestine and colon were dominated by ILC2s, with an increase in ILC1s observed in the colon after birth.

Conclusions: This study provides insights into the changes in ILC populations during prenatal and postnatal development in rat hematopoietic, lymphoid, and non-lymphoid organs, which can be valuable for researchers studying ILCs and improves the rat model in developmental biology.

Introduction: Mesenchymal stromal cells (MSCs) play a crucial role in tissue repair and exhibit anti-inflammatory properties, making them promising for regenerative medicine. Dental tissue-derived MSCs, such as stromal cells from human exfoliated deciduous teeth (SHEDs) and dental pulp stromal cells (DPSCs), express neural markers and hold the potential for treating neurodegenerative diseases. Nonetheless, their relative ability to differentiate into neurons is still unclear. Given their shared embryonic origin, we hypothesised that SHEDs and DPSCs possess similar potential for neuronal differentiation along with intrinsic expression of neuronal markers. The objective of this study was to compare their differentiation abilities under standardised conditions, evaluate neuronal markers pro- and post-neuronal induction, and compare the neuronal differentiation potential of SHEDs and DPSCs.

Methods: SHEDs (n = 3) and DPSCs (n = 3) were collected with ethical approval, cultured, and characterised according to established MSC criteria. Clonogenicity, proliferation, senescence, and trilineage differentiation were assessed. Neuronal differentiation was induced for 21 days and evaluated using flow cytometry (SRY-Box Transcription Factor 1 [SOX1], SRY-Box Transcription Factor 2 [SOX2], glial fibrillary acidic protein [GFAP], doublecortin, nestin, CD56, CD146), immunofluorescence for βIII-tubulin, reverse transcription polymerase chain reaction for tubulin 3 (TUB3), and microtubule-associated protein 2 (MAP2).

Results: Both SHEDs and DPSCs exhibited MSC characteristics. SHEDs showed higher clonogenicity. Early neuronal markers (e.g., SOX1, nestin, GFAP, βIII-tubulin) were detected pre- and post-induction in both cell types without significant intergroup differences. No significant expression of TUB3 and MAP2 was observed.

Conclusion: SHEDs and DPSCs show comparable neuronal marker expression profiles, suggesting similar early neuronal differentiation potential. These findings support using undifferentiated SHEDs and DPSCs in neuroregenerative strategies, offering cost-effective and safer alternatives to pre-differentiated cells.

Introduction: While caudal foregut development in human fetuses has been outlined in previous research, the formation of its border region remains unclear. This study aimed to visualize the precise timeline of caudal foregut boundary formation.

Methods: Three-dimensional images of the foregut from T1-weighted scans of 24 fetuses (crown-rump length [CRL]: 34-103 mm) were analyzed to measure the wall thickness and lumen diameter at nine specific sites. The internal structure in the border region was verified using histological sections and diffusion tensor imaging (DTI) tractography.

Results: The lower esophageal and pyloric canal walls were thicker in samples with a CRL ≥50 mm. The esophageal wall at the esophageal hiatus, where the lower esophageal sphincter is located, was particularly thick in samples with a CRL ≥88 mm. Increased wall thickness at the esophageal hiatus and pyloric canal resulted in a narrower lumen. The pyloric canal lumen narrowed from its distal to proximal sections. The lumen diameter-to-wall thickness ratio at the esophageal hiatus and proximal pyloric was negatively correlated with CRL. The thickened esophageal wall at the esophageal hiatus had a thick submucosa, and all layers in the pyloric canal thickened with growth. DTI tractography revealed that the lower esophageal wall mainly comprised longitudinal fibers, whereas the pyloric canal wall consisted solely of circular fibers, with fractional anisotropy increasing with growth.

Conclusion: This study provides a comprehensive timeline of normal caudal foregut boundary formation during the early human fetal period, thereby improving the understanding of congenital foregut obstruction pathogenesis.

Introduction: Surgical reconstruction is recommended for cleft palate patients. However, improper muscle reconstruction can cause scarring and velopharyngeal insufficiency. Understanding the developmental patterns of soft palatal musculature is crucial for improving treatments. Although mice are commonly used to investigate soft palate development, the uvula deficiency in mice limits their applicability. This study aimed to compare the developmental characteristics of soft palate muscles in miniature pigs and mice at various stages to better understand the patterns in large mammals.

Methods: Specimens of soft palate were collected from human embryos, miniature pigs, and mice at different stages. Furthermore, comprehensive gross observations, haematoxylin and eosin staining, and immunohistochemical analyses for myosin heavy chain and hypermethylated cancer 1 (Hic1) were conducted on multiple dissected sections.

Results: Mature soft palatal musculature exhibited anatomical and histological similarities across the three species. Notably, miniature pigs exhibited the uvula structure and uvula muscle (MU) development comparable to humans. Embryonic day 40 (E40, equivalent to human embryonic week 11, E11w) represented the early developmental stage of the MU, characterized by scattered muscle cells not yet coalescing into multinucleated fibres. By E45 (aligned with human E12w), the muscle bundles reached maturity, exhibiting two oriented fibre bundles flanking the midline. Levator veli palatini muscle and palatopharyngeus of miniature pigs exhibited a distinct course pattern due to the presence of the MU. Hic1+ perimysial cells were observed at the extending edge of the developing palatopharyngeus of miniature pigs, indicating a potential guiding role in the migration of myogenic cells.

Conclusion: Characterized by the MU, the spatiotemporal dynamic process of soft palatal musculature of miniature pigs was revealed. Miniature pigs exhibit a similar structure of the MU to that of humans and therefore serve as a promising model for researching soft palatal musculature development of large mammals in the future.

Introduction: Cytosolic carboxypeptidase 1 (CCP1) is a deglutamylase that antagonizes polyglutamylation. Mutations in human CCP1 gene cause a severe disease known as childhood-onset neurodegeneration with cerebellar atrophy (CONDCA), which is characterized by marked growth retardation. However, the role and mechanisms of CCP1 in skeletal development remain unclear.

Methods: In this study, we used CCP1 knockout (CCP1-KO) mice to assess bone mass changes by micro-CT, HE, alkaline phosphatase (ALP) staining, tartrate-resistant acid phosphatase staining and immunofluorescence staining. Changes in osteogenic differentiation, proliferation, and migration capacity of bone marrow mesenchymal stem cells (BMSCs) were assessed by ALP, alizarin red (ARS) staining, quantitative real-time PCR, EdU staining, and cell scratching assay. Then, tubulin glutamylation and primary cilia of BMSCs after deletion of CCP1 was analyzed by Western blot and immunofluorescence staining. Finally, CB839, an inhibitor of glutamine metabolism, was used to detect changes in the osteogenic differentiation ability and primary cilia of BMSCs after reducing the elevated glutamylation level.

Results: CCP1-KO mice exhibited phenotypes relevant to humans, including reduced body size, decreased bone mass, and reduced bone density during growth and development. CCP1 deficiency impairs the proliferation, migration, and osteogenic differentiation of BMSCs. Meanwhile, the number of pre-osteoblasts derived from BMSCs is decreased, leading to impaired osteogenesis. At the cellular level, CCP1 loss results in aberrant tubulin glutamylation, increased microtubule glutamylation, and shortened primary cilia in BMSCs. Finally, reduction of abnormally elevated tubulin glutamylation was efficacious for promoting osteogenic differentiation of BMSCs and restoring primary cilia length of BMSCs.

Conclusion: We propose that CCP1 plays a critical role in regulating BMSCs differentiation and promotes osteogenesis by modulating the post-translational modifications of tubulin, with a view to provide new targets for the prevention and treatment of hard tissue diseases.

Introduction: Endo-beta-N-acetylglucosaminidase (ENGASE) is one of the key enzymes involved in the structural and functional regulations of glycoproteins. Although its enzymatic activities and applications have been well studied in vitro, its biological function in vivo yet remains to be illustrated. In this study, the biological function of ENGASE in Caenorhabditis elegans was explored in detail.

Methods: An Engase gene knockout in C. elegans (CeEng-1 or CeEngase) was constructed and subjected to a panel of phenotypical and glycomics analysis. In addition, in vitro and in vivo ENGASE inhibition assays were performed.

Results: Engase knockout worm's adaptivity to environmental stresses (heat and osmotic) was significantly improved, and its longevity was also increased mildly. A clustered change in basement membrane proteins (e.g., LAM-1, LAM-2, and EPI-1) was illustrated by N-glycopeptide analysis, suggesting that ENGASE is involved in a basement membrane-based stress regulation. Then, the heat stress phenotype was further supported by in vivo CeEngase knockdown assay and in vitro and in vivo small compound inhibitory assay of CeENGASE, indicating that ENGASE is a potential drug target for stress management.

Conclusion: Engase is actively involved in a basement membrane-mediated stress adaptation and could serve as a potential target for healthcare products.

Introduction: Intracellular Ca2+ oscillations of unknown function occur in human adipose tissue stem cells (ASCs). In the present study, we investigated whether Ca2+ oscillations in ASCs from subcutaneous fat tissue derived from female patients were driving albumin endocytosis by involving the neonatal Fc receptor (FcRn), which is mediating the recycling of albumin and IgG.

Methods: Intracellular Ca2+ oscillations were monitored by Fluo-4 microfluorometry. Uptake of fluorescence-labeled albumin was assessed by confocal laser scanning microscopy in the presence of endocytotic pathway inhibitors. FcRn was inactivated either by use of the antagonizing antibody nipocalimab or siRNA technology.

Results: Endocytosis of albumin occurred by macropinocytosis (inhibition by cytochalasin D, wortmannin, and ethylisopropylamiloride [EIPA]), caveolae-dependent (inhibition by genistein and nystatin) and clathrin-mediated (inhibition by Dyngo-4a) pathways. In serum-free medium, Ca2+ oscillations were absent, but were induced by the addition of either fetal bovine serum, albumin, IgG or a stimulating antibody against FcRn. Consequently, FcRn expression was demonstrated in ASCs by Western blot analysis and immunohistochemistry, and colocalized with endocytosed albumin. Ca2+ oscillations were inhibited by the Ca2+ chelating agent BAPTA, the store-operated Ca2+ entry inhibitor SKF96365, the Ca2+-sensing receptor (CaSR) inhibitor NPS-2143, the macropinocytosis inhibitors cytochalasin D, wortmannin, and EIPA, the caveolae-dependent endocytosis inhibitors genistein and nystatin, and the clathrin-mediated endocytosis inhibitor Dyngo-4a. Uptake of fluorescence-labeled albumin was inhibited by agents interfering with Ca2+ oscillations and endocytosis blockers. Notably, not only intracellular albumin and IgG accumulation, but also Ca2+ oscillations were inhibited by the FcRn-blocking antibody nipocalimab, which interferes with the IgG binding site of FcRn. Moreover, siRNA-mediated downregulation of FcRn protein expression significantly reduced intracellular albumin content, the number of cells displaying Ca2+ oscillations, and the duration and amplitude of Ca2+ signals.

Conclusion: Our data suggest that Ca2+ oscillations in human ASCs regulate albumin uptake and presumably IgG recycling via FcRn.

Introduction: One of well-known exogenous fluorinated glucocorticoid that is used to treat inflammatory and various autoimmune illnesses is dexamethasone. Dexamethasone is known to cause skeletal muscular weakness and when used for an extended period of time, skeletal muscle undergoes atrophy. Granulocyte colony-stimulating factor (G-CSF) is a glycoprotein that helps mobilize stem cells from bone marrow into peripheral circulation. In order to maintain the function of skeletal muscle, these mobilized stem cells multiply and differentiate into mature myocytes. This study was conducted to investigate to what extent administration of filgrastim, human methionyl granulocyte colony-stimulating factor (G-CSF), ameliorates glucocorticoid-induced skeletal muscles damage in adult male albino rats.

Methods: Thirty adult male albino rats were randomly divided into three groups (ten/group), group I (control group, CG): rats received normal diet and orally given normal saline, group II (dexamethasone group, DG): rats were given dexamethasone at a dose of 0.5mg/kg for one month by intraperitoneal injection, group III (filgrastim group, FG): rats were given dexamethasone at dose of 0.5 mg/kg and on day 15, at the beginning of the third week, they were given Filgrastim at a dose of 20 µg/kg till the end of the 4th week by intraperitoneal injection with dexamethasone. Assessment of CK levels, total body weight and motor activity at different time points were done and skeletal muscles specimens were processed for light microscopy, electron microscopy and immunohistochemistry examination.

Results: Administration of dexamethasone (group II) showed variant types of pathological changes such as elevated CK, decrease in body weight, impairment of muscle activity and histologically myofibrillar disarrangement together with cellular infiltration and edema. Filgrastim group showed significant reduction in most of those manifestations. Administration of filgrastim with dexamethasone meliorated most of the symptoms related to dexamethasone induced-myopathy.

Conclusion: Filgrastim administration recovered manifestations of skeletal muscle injuries caused by dexamethasone.

Introduction: Mitochondrial studies are crucial for assessing livestock health and performance. While extensive research has been done on cattle and pigs, the influence of mitochondria in Indian buffalo remains unexplored. Therefore, in order to understand functions of mitochondria, their energy-related processes, or any additional mitochondrial traits in buffaloes, it is imperative to isolate high-yield mitochondria with purity and functionality. Mitochondria are extracted by few conventional buffers. These buffers were previously characterized for their effectiveness in isolating mitochondria from rodent and human tissues. Therefore, the present study is to assess the performance of mitochondria isolation buffers specifically in buffalo tissues.

Methods: The study involved isolation of mitochondria from four different tissues, i.e., liver, brain, heart and muscles of slaughtered buffalo (n = 3), using: (i) Tris-Mannitol buffer (ii) Tris-Sucrose buffer, and (iii) MOPS-Sucrose buffer. Buffer efficiency in preserving high fidelity during mitochondria isolation was assessed by comparison with Cayman's MitoCheck® Mitochondrial Isolation Kit (control). Further mitochondrial purity and functionality was assessed through comparative estimation of protein concentration and marker enzyme assays, respectively.

Results: Our results revealed insights into the suitability of specific buffer for functional mitochondria isolation from specific type of buffalo tissue. Notably for obtaining high quality functional mitochondria from buffalo, MOPS-Sucrose buffer appeared optimal for soft tissues (liver and brain), while Tris-Mannitol buffer was efficient for hard tissues (muscles and heart).

Conclusions: Thus, our research highlights the influence of buffer composition and tissue-specific variations in buffer effectiveness on mitochondrial activity in different tissues, leading to improved mitochondrial isolation in buffalo.