Hua Wang

IVDD represents a major etiology of lower back pain in the elderly [1], contributing significantly to global disability and health care burdens. Risk factors associated with this pathology include ...

Mesenchymal stromal cells (MSCs) hold significant promise in regenerative medicine, yet their clinical application is hindered by challenges such as cellular heterogeneity and quality control. This study aims to develop a rapid, noninvasive method for evaluating the quality of MSCs using femtosecond laser label-free imaging (FLI). We examined the proliferation, metabolic dynamics, and differentiation potential of MSCs from various tissue sources, including human dental pulp, umbilical cord, and fat, across different passages. Conventional experiments show that as the number of passages increases, the morphology of MSCs alters, proliferation capacity decreases, β-galactosidase activity linked to aging rises, and both osteogenic and adipogenic differentiation abilities markedly decline. FLI technology effectively captures these changes: reduced NAD(P)H/FAD ratio in higher-passage cells suggests decreased metabolic activity, while enhanced aging-related fluorescence signals, such as lipofuscin, align with cellular senescence. In the assessment of differentiation capability, increased fluorescence intensity of NAD(P)H and FAD signals indicates heightened metabolic activity within the cells. With the passages increasing, the fluorescence intensities of NAD(P)H and FAD decline, suggesting diminished ability of cell differentiation. Furthermore, during osteogenic differentiation, the optical REDOX ratio (FAD/(NAD(P)H + FAD)) decreases with successive passages, whereas during adipogenic differentiation, it increases. Three-dimensional FLI of suspension cells further reveals that the cells of lower-passage exhibit greater spatial heterogeneity in metabolic signals, possibly reflecting more active mitochondrial function. This study demonstrates that FLI technology can effectively assess the proliferation activity, senescence, and differentiation potential of MSCs through noninvasive, dynamic monitoring of their metabolic status and morphological features, offering a novel approach for standardized quality assessment of MSCs preparations.

High‐altitude pulmonary edema (HAPE) is a life‐threatening disorder caused by hypobaric hypoxia and characterized by pulmonary injury, oxidative stress, and inflammation. We investigated the effects of small extracellular vesicles derived from dental pulp stem cells (DPSCs‐sEVs) in a rat model of HAPE as well as hypoxia‐injured pulmonary microvascular endothelial cells (PMVECs). Rats were exposed to hypobaric hypoxia for 96 h. Lung injury was assessed by histology and immunofluorescence (VEGF, TNF‐α, Occludin). Pulmonary permeability was evaluated by total protein in bronchoalveolar lavage fluid and lung homogenates and by Na ⁺ /K ⁺ ‐ATPase activity. Oxidative stress, inflammatory mediators, and vasoactive factors (NO, PGI₂) were measured. DPSCs‐sEVs attenuated hypoxia‐induced lung injury, increased VEGF and Occludin, reduced TNF‐α, decreased protein leakage, and enhanced Na ⁺ /K ⁺ ‐ATPase activity. DPSCs‐sEVs alleviated oxidative stress and upregulated Nrf2, HO‐1, and GPX1. In vivo, dexamethasone served as a reference treatment; DPSCs‐sEVs produced greater improvements in most endpoints, with comparable effects in selected measures. In PMVECs, DPSCs‐sEVs dose‐dependently mitigated hypoxia‐induced dysfunction. These findings suggest DPSCs‐sEVs protect against hypoxia‐induced pulmonary injury by preserving barrier integrity and improving redox and inflammatory homeostasis.

Atherosclerosis (AS), a leading cause of cardiovascular disease (CVD), is closely associated with excessive oxidative stress. Dietary nitrate has emerged as a promising intervention for cardiovascular protection through the nitrate–nitrite–nitric oxide (NO) pathway. Meanwhile, dental pulp stem cell (DPSC) possess potent antioxidant properties. However, the potential synergistic effect of sodium nitrate (NaNO ₃ ) and DPSC on AS remains unclear. In this study, ApoE ^−/− mice were fed a high‐fat diet (HFD) and treated with NaNO ₃ and/or DPSC. The combined treatment markedly attenuated atherosclerotic plaque formation, reduced oxidative stress, increased endothelial NO synthase (eNOS) expression, and decreased circulating monocyte levels. Furthermore, in vitro assays revealed that NaNO ₃ and DPSC synergistically alleviated oxidative stress and promoted macrophage polarization toward the M2 phenotype, thereby suppressing oxidized lipid uptake. Mechanistic studies revealed that these benefits were mediated by activation of the nuclear factor erythroid 2‐related factor 2 (Nrf2) signaling pathway and the subsequent upregulation of heme oxygenase‐1 (HO‐1). Collectively, our findings unveil a novel therapeutic strategy that combines NaNO ₃ with DPSC to alleviate oxidative stress and inflammation, presenting a promising approach for the treatment of AS.

Mesenchymal stem cells (MSCs) hold significant promise in regenerative medicine, yet their clinical application is hindered by challenges such as cellular heterogeneity and quality control. This study aims to develop a rapid, non-invasive method for evaluating MSCs quality using femtosecond laser label-free imaging (FLI). We examined the proliferation, metabolic dynamics, and differentiation potential of MSCs from various tissue sources, including human dental pulp, umbilical cord, and fat, across different passages. Our findings indicate that with the passages increasing, the morphology of MSCs alters, proliferation capacity decreases, β-galactosidase activity linked to aging rises, and both osteogenic and adipogenic differentiation abilities markedly decline. FLI technology effectively captures these changes: reduced NAD(P)H/FAD ratio in the cells of higher passage suggests decreased metabolic activity, while enhanced aging-related fluorescence signals, such as lipofuscin, align with cellular senescence. During differentiation, increased fluorescence intensity of NAD(P)H and FAD signals heightened metabolic activity within the cells. Due to varying differentiation potentials among cells from different sources, NAD(P)H and FAD change patterns also differ. Difference in the optical REDOX ratio (FAD/(NAD(P)H+FAD)) among differentiation directions indicate that differentiation potential of MSCs correlates with metabolic reprogramming. Three-dimensional FLI of suspension cells further revealed that the cells of lower-passage exhibit greater spatial heterogeneity in metabolic signals, possibly reflecting more active mitochondrial function. This study confirms that FLI technology can effectively assess the proliferation activity, senescence, and differentiation potential of MSCs through non-invasive, dynamic monitoring of their metabolic status and morphological features, offering a novel approach for standardized quality assessment of MSCs preparations.

Growth differentiation factor 15 (GDF15), a hypoxia-responsive mediator in myocardial injury, is established as a mitochondrial stress biomarker in skeletal muscle. However, its mechanistic role in regulating mitophagy during cardiac hypoxia remains unknown. In this study, human myocardial cells (AC16) were treated with cobalt chloride (CoCl₂) to induce hypoxia. GDF15 expression was analyzed using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot. Cells were transfected with GDF15-knockdown lentivirus (LV-shGDF15) or overexpression lentivirus (LV-GDF15), and proliferation was monitored in real-time under normoxia or hypoxia using the iCELLigence RTCA DP and SP system. Mitochondrial function was assessed through lactate dehydrogenase (LDH) activity, superoxide dismutase (SOD) activity, malonaldehyde (MDA) concentration, cytosolic reactive oxygen species (ROS), mitochondrial transmembrane potential (ΔΨm), and oxygen consumption rate (OCR) analysis. To validate sequencing results, BCL2/Adenovirus E1B Interacting Protein 3(BNIP3) was knocked down using siRNA in LV-shGDF15 cells and overexpressed via plasmid in the LV-GDF15 group before evaluating ΔΨm and ROS. The effects on mitochondrial homeostasis were further assessed through RNA sequencing and mitochondrial functional analyses. The proliferative ability of GDF15 knockdown cells was significantly decreased, accompanied by an increase in lactate dehydrogenase release. Overexpression of GDF15 significantly inhibited the accumulation of ROS and prevented ΔΨm loss. Administering GDF15 (50 ng/ml) to GDF15 knockdown cells effectively reduced MDA and ROS expression and mitigated ΔΨm loss. GDF15 protected AC16 cells from CoCl₂-induced hypoxic injury. LV-shGDF15 cells with BNIP3 knockdown and CoCl₂ treatment exhibited decreased levels of BNIP3 and LC3B-II, increased ΔΨm, and reduced ROS expression. Conversely, GDF15 overexpression significantly reduces BNIP3 levels, diminishes BNIP3-driven aberrant autophagosome biogenesis, and concurrently enhances lysosomal activity. This study unveils a novel cardioprotective mechanism of GDF15 through BNIP3 suppression and characterizes its temporal expression dynamics under hypoxia. GDF15 mitigates hypoxic injury by downregulating BNIP3, thereby curbing pathological mitophagy, activating lysosomes function, and offering a therapeutic target for ischemic cardiomyopathy.

Chronic kidney disease (CKD) is a major global health problem characterized by renal fibrosis, for which effective therapeutic options are still lacking. Mesenchymal stem cells (MSCs) have emerged as potential candidates for treating fibrosis due to their paracrine effects. This study first compared the antifibrotic capacities of umbilical cord-derived MSCs (UCMSCs) and dental pulp stem cells (DPSCs). The results showed that DPSCs exhibited superior effects in suppressing fibrosis markers and improving the fibrotic microenvironment. Thus, subsequent studies focused on DPSC and their hepatocyte growth factor (HGF)-modified counterpart (HGF-DPSC). Using an in vivo unilateral ureteral obstruction (UUO) mouse model and an in vitro Transforming Growth Factor-Beta 1(TGF-β1)-induced Human Renal Proximal Tubule Epithelial Cell (HK-2 cell) model, this study systematically evaluated the promising antifibrotic effects and mechanisms of DPSC. The results demonstrated that HGF-DPSC significantly improved the fibrotic microenvironment by regulating the Phosphoinositide 3-Kinase/Protein Kinase B/Glycogen Synthase Kinase 3 Beta (PI3K/AKT/GSK3β) signaling pathway and suppressing β-catenin activation. We confirmed direct protein–protein interaction between HGF and Iodothyronine Deiodinase 2 (DIO2) through co-immunoprecipitation (Co-IP), which suggested a novel molecular mechanism by which HGF-DPSC exerts its antifibrotic effects. These findings highlight the multitarget mechanism of HGF-DPSC in the treatment of renal fibrosis and provide new insights and possibilities for the treatment of CKD.