Developmental patterns of Ki-67, bcl-2 and caspase-3 proteins expression in the human upper jaw

Evaluation of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in human cases with orofacial clefts: A systematic review

INTRODUCTION

The interaction between several cell populations or many genes and the coordination of multiple signal transmission pathways can lead to defects such as orofacial clefts (OFCs). Herein, a systematic review was designed to evaluate a group of important biomarkers (matrix metalloproteinases [MMPs] and tissue inhibitors of metalloproteinases [TIMPs]) in human cases with OFCs.

MATERIAL AND METHODS

Four databases including PubMed, Scopus, Web of Science, and Cochrane Library databases were searched until March 10, 2023, without any restriction. STRING, the protein-protein interaction (PPI) network software, was applied to investigate the functional interactions among the examined genes. The effect sizes including odds ratio (OR) dealing with a 95% confidence interval (CI), were extracted by the Comprehensive Meta-Analysis version 2.0 (CMA 2.0) software.

RESULTS

Thirty-one articles were entered into the systematic review that four articles were analyzed in the meta-analysis. Single studies reported that several polymorphisms of MMPs (rs243865, rs9923304, rs17576, rs6094237, rs7119194, and rs7188573); and TIMPs (rs8179096, rs7502916, rs4789936, rs6501266, rs7211674, rs7212662, and rs242082) had an association with OFC risk. There was no significant difference for MMP-3 rs3025058 polymorphism in allelic (OR: 0.832; P=0.490), dominant (OR: 1.177; P=0.873), and recessive (OR: 0.363; P=0.433) models and MMP-9 rs17576 polymorphism in an allelic model (OR: 0.885; P=0.107) between the OFC cases and the controls. Based on immunohistochemistry reports, three MMPs (MMP-2, MMP-8, and MMP-9) and TIMP-2 had significant correlations with several other biomarkers in OFC cases.

CONCLUSIONS

MMPs and TIMPs can impact the tissue and cells affected by OFCs and the process of apoptosis. The interaction between some biomarkers with MMPs and TIMPs (e.g., TGFb1) in OFCs can be interesting for future research.

Trigeminal neurons control immune-bone cell interaction and metabolism in apical periodontitis

Abstract

Apical periodontitis (AP) is an inflammatory disease occurring following tooth infection with distinct osteolytic activity. Despite increasing evidence that sensory neurons participate in regulation of non-neuronal cells, their role in the development of AP is largely unknown. We hypothesized that trigeminal ganglia (TG) Nav1.8⁺ nociceptors regulate bone metabolism changes in response to AP. A selective ablation of nociceptive neurons in Nav1.8^Cre/Diphtheria toxin A (DTA)^Lox mouse line was used to evaluate the development and progression of AP using murine model of infection-induced AP. Ablation of Nav1.8⁺ nociceptors had earlier progression of AP with larger osteolytic lesions. Immunohistochemical and RNAscope analyses demonstrated greater number of macrophages, T-cells, osteoclast and osteoblast precursors and an increased RANKL:OPG ratio at earlier time points among Nav1.8^Cre/ DTA^Lox mice. There was an increased expression of IL-1α and IL-6 within lesions of nociceptor-ablated mice. Further, co-culture experiments demonstrated that TG neurons promoted osteoblast mineralization and inhibited osteoclastic function. The findings suggest that TG Nav1.8⁺ neurons contribute to modulation of the AP development by delaying the influx of immune cells, promoting osteoblastic differentiation, and decreasing osteoclastic activities. This newly uncovered mechanism could become a therapeutic strategy for the treatment of AP and minimize the persistence of osteolytic lesions in refractory cases.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00018-022-04335-w.

Spatio-Temporal Expression Pattern of Ki-67, pRB, MMP-9 and Bax in Human Secondary Palate Development

We analyzed the immunohistochemical expression of Ki-67, pRb, Bax, and MMP-9 during the human secondary palate formation (7th to 12th developmental weeks (DWs). The most significant proliferation was observed in the seventh DW with 32% of Ki-67-positive cells in the epithelium, while loose ectomesenchyme condensations (lec) and loose non-condensing ectomesenchyme (lnc) had only 18 and 11%, respectively (Kruskal–Wallis, p < 0.001), and diminished afterwards. Contrarily, pRb-positive cells were mostly located in the lnc (67%), with significant difference in comparison to epithelium and lec in all investigated periods (Kruskal–Wallis, p < 0.001). Ki-67- and pRb-positive cells co-expressed occasionally in all investigated periods. MMP-9 displayed a strong expression pattern with the highest number of positive cells during the seventh DW in the epithelium, with significant difference in comparison to lec and lnc (Kruskal–Wallis, p < 0.0001). The ninth DW is particularly important for the Bax expression, especially in the epithelium (84%), in comparison to lec (58%) and lnc (47%) (Kruskal–Wallis, p < 0.001). The co-expression of Bax and MMP-9 was seen only in the epithelium during seventh and ninth DWs. Our study indicates the parallel persistence of proliferation (Ki-67, pRb) and remodeling (MMP-9) that enables growth and apoptotic activity (Bax) that enable the removal of the epithelial cells at the fusion point during secondary palate formation.

Expression of apoptotic and proliferation factors in gastric mucosa of patients with systemic sclerosis correlates with form of the disease

Despite high prevalence of patients with gastric disease in systemic sclerosis (SSc), its pathogenesis is still poorly understood. We immunohistochemically analysed biopsies of gastric mucosa (GM) in 5 controls and 15 patients with different forms of SSc: limited cutaneous (lc), diffuse cutaneous moderate (sys1) and severe (sys2). The number of positive cells was analysed by a Kruskall-Wallis test, P < 0.05 was considered statistically significant. Percentage of proliferating (Ki-67 positive) cells was highest in sys1 (3% in superficial and 4,6% in deeper parts of GM), which dropped to 1% in sys2. Percentage of α-smooth muscle actin (α-SMA) positive cells was 5% in controls, 9% in superficial GM, while in deeper GM rose from 7% to 19% in sys1 and sys2, thus indicating increased myofibroblast population. Caspase-3 positive apoptotic cells characterized 1,5–2% of controls, 8% of superficial and 6% of deeper GM cells in sys1. In sys2, apoptosis affected 50% of surface epithelial and gland cells and 30% of deeper glands, and correlated with increased fibrosis and decreased syndecan-1 expression. Our data demonstrate that sys1 is the most „active” proliferating form of SSc. Sys2 characterize collagen deposition, surface epithelium defects, extensive apoptosis and low proliferation, GM atrophy and loss of function.

Spatiotemporal distribution of proliferation, proapoptotic and antiapoptotic factors in the early human limb development

Involvement of proliferation and apoptosis in the human limb development was analyzed electronmicroscopically and immunohistochemically in histological sections of 8 human embryos, 4(th) -10(th) week old, using apoptotic (caspase-3, AIF, BAX), anti-apoptotic (Bcl-2) and proliferation (Ki-67) markers, and TUNEL method. The data were analyzed by Mann-Whitney test, Kruskal-Wallis and Dunn's post hoc test. Initially, developing human limbs consisted of mesenchymal core and surface ectoderm with apical ectodermal ridge (AER). During progression of development, strong proliferation activity gradually decreased in the mesenchyme (from 78% to 68%) and in the epithelium (from 62% to 42%), while in the differentiating finger cartilages proliferation was constantly low (26-7%). Apoptotic caspase-3 and AIF-positive cells characterized mesenchyme and AER at earliest stages, while during digit separation they appeared in interdigital mesenchyme as well. Strong Bcl-2 expression was observed in AER, subridge mesenchyme and phalanges, while BAX expression charaterized limb areas undergoing apoptosis. Ultrastructurally, proliferating cells showed mitotic figures, while apoptotic cells were characterized by nuclear fragmentation. Macrophages were observed around the apoptotic cells. We suggest that intense proliferation enables growth and elongation of human limb primordia, and differential growth of digits. Both caspase-3 and AIF-dependant pathways of cell death control the extent of AER and numer of cells in the subridge mesenchyme at earliest developmental stages, as well as process of digit separation at later stages of limb development. Spatio-temporal co-expresson of Bcl-2 and BAX indicates their role in suppression of apoptosis and selective stimulation of growth during human limb morphogenesis.

Interplay of proliferation and proapoptotic and antiapoptotic factors is revealed in the early human inner ear development

HYPOTHESIS

Spatiotemporal interplay of factors controlling proliferation, differentiation and apoptosis within the developing human inner ear is essential for labyrinth morphogenesis and development of vestibular and cochlear functions.

BACKGROUND

Studies on the early human inner ear development are scarce and insufficient.

METHODS

The immunolocalization of Ki-67, Bcl-2, caspase-3, and IGF-1 was analyzed in 6 human inner ears, 5 to 10 gestational weeks old. Statistical data were analyzed using the Kruskal-Wallis test.

RESULTS

During the analyzed period, the otocyst has transformed into cochlear duct and saccule ventrally and semicircular canals and utricle dorsally. Initial differentiation of sensorineural fields characterized organ of Corti, maculae, and cristae ampullares. Intense (50%) and evenly distributed proliferation Ki-67 in the otocyst decreased to 24% to 30% and became spatially restricted within the membranous labyrinth epithelium. Simultaneously, expression of antiapoptotic Bcl-2 protein increased in sensorineural fields of organ of Corti, macula, and crista ampullaris. Throughout the investigated period, apoptotic caspase-3 positive cells were mainly distributed at the luminal and basal surfaces of labyrinth epithelium. An inhibitor of apoptosis IGF-1 co-expressed with Bcl-2 and increased in the sensorineural fields with advancing development.

CONCLUSION

The described expression pattern indicates roles for cell proliferation in the growth of the inner ear and Bcl-2 in differentiation of sensorineural fields and protection from apoptosis. Both IGF-1-and caspase-3-mediated apoptosis seem to contribute to proper morphogenesis, differentiation, and innervations of sensorineural fields within the cochlea, semicircular canals, saccule, and utricle. Alterations in spatiotemporal interplay of investigated factors might lead to disturbances of vestibular and cochlear function.

Cell proliferation and apoptosis in the fusion of human primary and secondary palates

The markers of cell proliferation (Ki-67) and apoptosis [caspase-3, TdT-mediated biotin-dUTP nick-end labelling (TUNEL)] and the expression of syndecan-1 and heat shock protein 70 (Hsp70) were analyzed immunohistochemically in 11 developing human palates, from developmental weeks 6 to 10. During fusion of the primary palate, the proportion of proliferating cells decreased from 42 to 32% and the proportion of apoptotic cells decreased from 11 to 7% in the medial-edge epithelium. At later stages, the proportions of both types of cells decreased in the ectomesenchyme, except for proliferating cells in its non-condensing part. At developmental weeks 9-10, the epithelial seam in the secondary palate comprised 28% proliferative cells and 5% apoptotic cells. While condensing ectomesenchyme contained more apoptotic cells than proliferating cells, the opposite was observed for the non-condensing ectomesenchyme. Co-expression of syndecan-1 and Hsp70 was detected in cells budding from the epithelial seam. Our study indicates similar principles for human primary palate and secondary palate fusion, and parallel persistence of proliferation and apoptotic activity. While proliferation enables growth and fusion of different palatal primordia, apoptosis results in the removal of of large numbers epithelial cells at the fusion point. The disintegration of seam remnants seems to be executed through the processes of change in protein content and cell migration, probably leading to cell death as their final outcome.