Effect of NF-κB Haploinsufficiency on Calvarial Bone Healing

Bone defect is a major and challenging health concern. The treatment for bone defect aims to enhance bone regeneration, which is highly regulated by many molecular signaling pathways. Growing evidence suggested that proper inflammatory signaling was crucial for bone regeneration. Previous study showed that treatment of MSCs with expression of NF-κB increased MSCs engraftment in damaged tissue. Previous work in our lab indicated a role of NF-κB on osteoblast differentiation during physiological bone development. The present study was designed to study role of NF-κB signaling in bone healing using genetically-modified mouse with haploinsufficiency of p65 in osteoblasts. Here, we showed that mice with osteoprogenitor-specific NF-κB haploinsufficiency displayed reduced calvarial defect bone repair manifested by micro-CT and histological analysis. The progenitor cells from p65 haploinsufficient mice demonstrated fewer CFU-OB colonies and decreased osteoblastic markers expression (Sp7, Alp and Bsp) in response to rhBMP2. Furthermore, rhBMP2 mediated Smad phosphorylation was disrupted in the absence of sufficient p65 signal. Therefore, we concluded that NF-κB haploinsufficiency impairs bone repair by downregulation of BMP2 mediated canonical Smads signaling and osteogenic differentiation. The effect of inflammatory mediators on bone formation was complex and yet to be elucidated. Based on our findings, we proposed a direct regulatory role of NF-κB in rhBMP2 mediated bone repair, suggesting that sufficient inflammatory cues are essential for bone regeneration. Uncovering the function of NF-κB in MSC-mediated repair will improve understanding of bone regeneration mechanism and provide a clue for bone regenerative therapy for treatment of bony defect.Doctor of Philosoph

RhoA-Mediated Functions in C3H10T1/2 Osteoprogenitors Are Substrate Topography Dependent: TOPOGRAPHY-DEPENDENT RhoA MEDIATED FUNCTIONS

Surface topography broadly influences cellular responses. Adherent cell activities are regulated, in part, by RhoA, a member of the Rho-family of GTPases. In this study, we evaluated the influence of surface topography on RhoA activity and associated cellular functions. The murine mesenchymal stem cell line C3H10T1/2 cells (osteoprogenitor cells) were cultured on titanium substrates with smooth topography (S), microtopography (M), and nanotopography (N) to evaluate the effect of surface topography on RhoA-mediated functions (cell spreading, adhesion, migration, and osteogenic differentiation). The influence of RhoA activity in the context of surface topography was also elucidated using RhoA pharmacologic inhibitor. Following adhesion, M and N adherent cells developed multiple projections, while S adherent cells had flattened and widespread morphology. RhoA inhibitor induced remarkable longer and thinner cytoplasmic projections on all surfaces. Cell adhesion and osteogenic differentiation was topography dependent with S < M and N surfaces. RhoA inhibition increased adhesion on S and M surfaces, but not N surfaces. Cell migration in a wound healing assay was greater on S versus M versus N surfaces and RhoA inhibitor increased S adherent cell migration, but not N adherent cell migration. RhoA inhibitor enhanced osteogenic differentiation in S adherent cells, but not M or N adherent cells. RhoA activity was surface topography roughness dependent (S < M, N). RhoA activity and -mediated functions are influenced by surface topography. Smooth surface adherent cells appear highly sensitive to RhoA function, while nano-scale topography adherent cell may utilize alternative cellular signaling pathway(s) to influence adherent cellular functions regardless of RhoA activity

Mechanistic basis for mitigating drought tolerance by selenium application in tobacco (Nicotiana tabacum L.): a multi-omics approach

The lack of irrigation water in agricultural soils poses a significant constraint on global crop production. In-depth investigation into microRNAs (miRNAs) has been widely used to achieve a comprehensive understanding of plant defense mechanisms. However, there is limited knowledge on the association of miRNAs with drought tolerance in cigar tobacco. In this study, a hydroponic experiment was carried out to identify changes in plant physiological characteristics, miRNA expression and metabolite profile under drought stress, and examine the mitigating effects of selenium (Se) application. The shoot dry weight of drought-stressed plants was approximately half (50.3%) of that in non-stressed (control) conditions. However, plants supplied with Se attained 38.8% greater shoot dry weight as compared to plants with no Se supply under drought stress. Thirteen miRNAs were identified to be associated with drought tolerance. These included 7 known (such as nta-miR156b and nta-miR166a) and 6 novel miRNAs (such as novel-nta-miR156-5p and novel-nta-miR209-5p) with the target genes of squamosa promoter-binding-like protein 4 (SPL4), serine/threonine protein phosphatase 2A (PPP2A), cation/calcium exchanger 4-like (CCX4), extensin-1-like (EXT1) and reduced wall acetylation 2 (RWA2). Further investigation revealed that the expression levels of Ext1 and RWA2 were significantly decreased under drought stress but increased with Se addition. Moreover, key metabolites such as catechin and N-acetylneuraminic acid were identified, which may play a role in the regulation of drought tolerance. The integrated analysis of miRNA sequencing and metabolome highlighted the significance of the novel-nta-miR97-5p- LRR-RLK- catechin pathway in regulating drought tolerance. Our findings provide valuable insights into the molecular mechanisms underlying drought tolerance and Se-induced stress alleviation in cigar tobacco

Survival outcomes and risk factors of patients with stage ⅡB cervical cancer undergoing neoadjuvant chemotherapy followed by radical hysterectomy

Objective To investigate the survival outcomes and risk factors of patients with stage ⅡB cervical cancer undergoing neoadjuvant chemotherapy (NACT) followed by laparoscopic radical hysterectomy (LRH). Methods A retrospective cohort study was conducted on 178 patients with stage ⅡB cervical cancer who underwent NACT followed by LRH in our department from 2015 to 2018. COX regression analysis was used to analyze the surgical pathological characteristics, and stratified analysis was performed according to the results. Kaplan-Meier survival curve analysis and log-Rank test were employed to analyze the survival outcomes of different subgroups. Results For the 178 subjected patients, their median follow-up period was 51 months, and the rates of 3-year disease-free survival (DFS) and overall survival (OS) were 75.4% and 82.6%, respectively. COX regression analysis showed that lymph node metastasis (LNM) (HR: 2.04, 95%CI: 1.16~3.60) and deep stromal invasion (DSI) (HR: 4.72, 95%CI: 2.11~10.60) were independent risk factors for DFS. LNM (HR: 2.77, 95%CI: 1.48~5.22), DSI (HR: 4.24, 95%CI: 1.64~10.98) and tumor diameter ≥4 cm after NACT (HR: 2.12, 95%CI: 1.14~3.94) were independent risk factors for OS. The rates of 3-year DFS of patients with and without LNM was 55.3% and 81.0% (P 50% after NACT were significantly better than those ≤50% (the 3-year DFS rate: 92.9% vs 71.0%, P 50% after NACT have better survival outcomes. LNM, DSI and tumor diameter ≥4 cm after NACT are independent risk factors for the prognosis of stage ⅡB cervical cancer

Comparative Study on Trace Element Excretions between Nonanuric and Anuric Patients Undergoing Continuous Ambulatory Peritoneal Dialysis

Few studies have been reported on alterations of trace elements (TE) in peritoneal dialysis patients. Our objective was to investigate and assess the characteristics of daily TE excretions in continuous ambulatory peritoneal dialysis (CAPD) patients. This cross-sectional study included 61 CAPD patients (nonanuric/anuric: 45/16) and 11 healthy subjects in Wuhan, China between 2013 and 2014. The dialysate and urine of patients and urine of healthy subjects were collected. The concentrations of copper (Cu), zinc (Zn), selenium (Se), molybdenum (Mo), and arsenic (As) in dialysate and urine were determined using inductively coupled plasma mass spectrometer (ICP-MS). Various clinical variables were obtained from automatic biochemical analyzer. Daily Cu, Zn, Se, and Mo excretions in nonanuric patients were higher than healthy subjects, while arsenic excretion in anuric patients was lower. A strong and positive correlation was observed between Se and Mo excretion in both dialysate (β = 0.869, p &lt; 0.010) and urine (β = 0.968, p &lt; 0.010). Furthermore, the clinical variables associated with Se excretion were found to be correlated with Mo excretion. Our findings indicated that nonanuric CAPD patients may suffer from deficiency of some essential TEs, while anuric patients are at risk of arsenic accumulation. A close association between Se and Mo excretion was also found