SOD2 promotes the immunosuppressive function of mesenchymal stem cells at the expense of adipocyte differentiation

Genetic Basis of Motor Neuron Diseases: Insights, Clinical Management, and Future Directions

Motor neuron diseases (MNDs) are a heterogeneous group of neurodegenerative disorders characterized by the progressive loss of motor neurons, resulting in debilitating physical decline. Advances in genetics have revolutionized the understanding of MNDs, elucidating critical genes such as SOD1, TARDBP, FUS, and C9orf72, which are implicated in their pathogenesis. Despite these breakthroughs, significant gaps persist in understanding the interplay between genetic and environmental factors, the role of rare variants, and epigenetic contributions. This review synthesizes current knowledge on the genetic landscape of MNDs, highlights challenges in linking genotype to phenotype, and discusses the promise of precision medicine approaches. Emphasis is placed on emerging strategies, such as gene therapy and targeted molecular interventions, offering hope for personalized treatments. Addressing these challenges is imperative to harness the full potential of genomics for improving outcomes in MNDs.

Phenethyl Isothiocyanate (PEITC) interaction with Keap1 activates the Nrf2 pathway and inhibits lipid accumulation in adipocytes

Phenethyl isothiocyanate (PEITC) has been recognized for its potential effects in various human diseases. However, the impact of PEITC on adipocyte differentiation and its underlying molecular mechanisms is not well understood. This study investigates the effects of PEITC on adipocyte differentiation and elucidates the molecular mechanisms involved in Nrf2 activation. The effects of PEITC on adipocyte differentiation were assessed in C3H10T1/2 and 3T3-L1 cells. Nrf2-induced effects by PEITC were examined in Nrf2 knockout (KO) MEF and Keap1 KO H1299 cells. The interaction between PEITC and Keap1 was evaluated using thermal shift assays and Co-immunoprecipitation experiments. Reconstitution of cysteine mutants of Keap1 in Keap1 KO cells was used to elucidate a critical amino acid for the PEITC-induced Nrf2 stabilization. The initial stages of adipogenesis were crucial for PEITC's anti-adipogenic effects in C3H10T1/2 and 3T3-L1 cells. PEITC increased Nrf2 protein expression, but this induction was absent in Keap1 KO cells. Thermal shift assays with the purified BTB domain of Keap1 confirmed a direct interaction with PEITC. Re-expression of Keap1 in Keap1 KO cells showed that the cysteine residue at position 151 is essential for PEITC-induced Nrf2 expression and the disruption of the Nrf2-Keap1 complex. PEITC was found to activate Nrf2-mediated gene expression and inhibit adipocyte differentiation, at least partially, through Nrf2-dependent mechanisms. This study confirms the anti-adipogenic effects of PEITC. Mechanistic investigations demonstrate that PEITC interacts with Keap1 and that the cysteine residue (C151) of Keap1 is critical for PEITC's effects on Nrf2 activation.

Basal and AT2 cells promote IPF-lung cancer co-occurrence via EMT: Single-cell analysis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrotic interstitial lung disease. With IPF, the probability of complication with lung cancer (LCA) increases considerably, and the prognosis is worse than that of simple IPF. To understand the pathological mechanisms and molecular pathways shared by these two diseases, we used the single-cell analysis from the Gene Expression Omnibus (GEO) database, and find that basal cells (BCs) and alveolar type 2 cells (AT2 cells) are important components of lung epithelial cells. Changes in molecular pathways in BCs and AT2 cells may be involved in the common pathogenesis of IPF and LCA. KRT17 and S100A14 in BCs may promote the IPF co-occurrence with LCA by mediating the EMT. WFDC2 and KRT19 may be the elements in AT2 cells that activate the EMT process to promote IPF co-occurrence with LCA. In both IPF and LCA, FN1-WNT axis may be involved in the interaction between BCs and AT2 cells. Importantly, the results of immunofluorescence colocalization experiments on tissue samples from patients with IPF and LCA were consistent with these conclusions. Basal-macrophage interactions may have also induced the IPF co-occurrence with LCA via the CYBA-ERK1/2 axis. The regulation of M2 macrophage polarization by JUN/SOD2-glycolysis axis may therefore be involved in the co-morbidity mechanism of IPF and LCA. Therefore, our results suggest that molecular changes in BCs, AT2 cells and macrophages may play important roles in the pathogenesis of IPF co-occurrence with LCA, and the cellular interactions between these cells may be critical for the progression of both diseases.

The role of cytokine licensing in shaping the therapeutic potential of wharton's jelly MSCs: metabolic shift towards immunomodulation at the expense of differentiation

BACKGROUND

Cytokine licensing with pro-inflammatory molecules, such as tumour necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ), has emerged as a promising strategy to enhance the therapeutic potential of multipotent mesenchymal stromal cells (MSCs). While licensing has demonstrated benefits for immunomodulation, its effects on other key MSC functions, including differentiation and paracrine activity, remain incompletely explored. In this study, we evaluated the transcriptomic, metabolomic, and functional changes induced by short-term TNF-α/IFN-γ priming of Wharton's jelly-derived MSCs (WJ-MSCs).

METHODS

WJ-MSCs were expanded and exposed to TNF-α and IFN-γ (10 ng/ml each) for 24 h. Transcriptomic analysis was performed using RNA sequencing to identify differentially expressed genes related to immune modulation and lineage commitment. Metabolomic profiling was conducted using high-resolution mass spectrometry to assess changes in metabolic pathways. Functional assays evaluated the effects of cytokine priming on induced differentiation and growth factor secretion.

RESULTS

Cytokine licensing induced notable alterations in gene expression, upregulating pathways linked to immune response, inflammation, and cytokine signalling. However, short-term cytokine treatment significantly attenuated the osteogenic and adipogenic differentiation of MSCs, as evidenced by the reduced expression of RUNX2, ALP, CEBPA, and PPARG. The priming had a negligible effect on EGF, FGF-2, HGF, LIF, and SCF secretion. The production of VEGF-A and VEGF-C was elevated, although the levels remained low. Metabolomic analysis revealed enhanced kynurenine pathway activity, indicative of increased tryptophan catabolism, accompanied by elevated levels of fatty acids and polyamines.

CONCLUSIONS

Our findings demonstrate that TNF-α/IFN-γ priming reprograms WJ-MSCs by enhancing their immunomodulatory capacity at the expense of differentiation potential. These results highlight the need for tailored strategies to optimize MSC functionality for specific clinical applications.

Serum miR-365b-5p/miR-222-5p as a potential diagnostic biomarker for long-term weight loss in patients with morbid obesity after bariatric surgery

BACKGROUND

The successful weight loss following bariatric surgery is not achieved in all patients with morbid obesity (MO). This study aims to determine whether a serum miRNA profile can predict this outcome.

DESIGN

Thirty-three patients with MO were classified in "Good Responders" (GR, percentage of excess weight loss (%EWL) ≥ 50 %) or "Non-Responders" (NR, %EWL < 50 %) according to the %EWL 5-8 year following bariatric surgery. Baseline serum miRNA sequencing was performed to find predictor biomarkers and human adipocyte culture were performed to determine their effect.

RESULTS

Fifty-six differentially expressed miRNAs were found between GR and NR. Logistic regression models showed two miRNAs, hsa-miR-365b-5p (upregulated in GR) and hsa-miR-222-5p (upregulated in NR) associated to %EWL. Receiver operating characteristic curves showed that the combination of these miRNAs was the best serum miRNAs profile that distinguished between GR and NR. The experimentally validated target genes of these miRNAs were involved in processes related to the response to stress, cell cycle, transduction, and development and proliferation processes. The in vitro expression of six genes involved in adipogenesis and adipocyte differentiation (STAT3, ILR7, PARP1, SOD2, FGF2 and TMEM18) was downregulated in lipogenic and upregulated in lipolitic conditions in human adipocytes incubated with the combination of a hsa-miR-365b-5p mimic and a hsa-miR-222-5p inhibitor.

CONCLUSIONS

Baseline serum hsa-miR-365b-5p and hsa-miR-222-5p were able to predict %EWL 5-8 years following bariatric surgery. The combination of these potential predictive biomarkers was involved in regulating the expression levels of genes associated with obesity. However, these effects could be modified depending of other stimuli.

Mechanical sensing protein PIEZO1 controls osteoarthritis via glycolysis mediated mesenchymal stem cells-Th17 cells crosstalk

Aberrant mechanical stimuli can cause tissue attrition and activate mechanosensitive intracellular signaling, impacting the progression of osteoarthritis (OA). However, the precise relationship between mechanical loading and bone metabolism remains unclear. Here, we present evidence that Piezo1 senses the mechanical stimuli to coordinate the crosstalk between mesenchymal stem cells (MSCs) and T helper 17 (Th17) cells, leading to the deterioration of bone and cartilage in osteoarthritis (OA). Mechanical loading impaired the property of MSCs by inhibiting their osteo-chondrogenic differentiation and promoting inflammatory signaling to enhance Th17 cells. Mechanistically, mechanical stimuli activated Piezo1, thereby facilitating Ca2+ influx which upregulated the activity of Hexokinase 2(HK2), the rate-limiting enzyme of glycolysis. The resultant increase in glycolytic activity enhanced communication between MSCs and T cells, thus promoting Th17 cell polarization in a macrophage migration inhibitory factor (MIF) dependent manner. Functionally, Wnt1cre; Piezo1fl/fl mice reduced bone and cartilage erosion in the temporomandibular joint condyle following mechanical loading compared to control groups. Additionally, we observed activated Piezo1 and HK2-mediated glycolysis in patients with temporomandibular joint OA, thereby confirming the clinical relevance of our findings. Overall, our results provide insights into how Piezo1 in MSCs coordinates with mechano-inflammatory signaling to regulate bone metabolism. The schema shows that mechanical sensing protein PIEZO1 in MSCs controls osteoarthritis via glycolysis mediated MSCs and Th17 cells crosstalk in a MIF dependent manner.

Melatonin ameliorates Pb-induced mitochondrial homeostasis and ovarian damage through regulating the p38 signaling pathway

Lead (Pb), a widespread metallic pollutant in the environment, has been found to have detrimental effects on the female reproduction system. Recently, our group discovered a significant correlation between toxic metals and reproductive endocrine diseases. However, there is limited research on the relationship between blood concentration of Pb and the risk of diminished ovarian reserve function (DOR). Melatonin (MT), as a unique antioxidant, has been shown to reduce Pb toxicity both in vivo and in vitro，but the role of MT on follicle development in Pb-exposed female C57BL6 mice, and the underlying mechanisms, have not been clearly identified. In this study, blood Pb level was detected in the DOR patients, and a significant elevation in Pb levels was observed compared to the control group. Subsequently, we investigated the impact of lead acetate trihydrate (0.2 %), an endocrine disruptor of heavy metals, on follicle development in mice. We observed abnormal follicle development induced by lead acetate trihydrate without concurrent follicular apoptosis or excessive autophagy. Furthermore, we found that co-treatment with MT (30 mg/kg) rescued Pb-induced abnormal follicle development. Anti-Müllerian hormone (AMH) is a commonly utilized marker to evaluate ovarian reserve function. Our observation revealed that MT treatment effectively reversed the decrease in AMH levels induced by Pb. Importantly, our results revealed that MT not only protected against the Pb-induced increase of nucleus-encoded proteins, including SDHA, mitofilin and MTCO2, but also rescued Pb-induced the increase of mitochondrial dynamic-related proteins, such as OPA1, MFN and FIS1. In addition, MT protected against the decrease of mitochondrial dynamic-related protein anti-mitochondrial fission factor (MFF) antibody expression and mitochondrial membrane potential level. Finally, MT rescued the Pb-induced inhibition of phosphorylation in the P38 signaling pathway. Conclusively, these findings provide compelling evidence that exposure to Pb influences mitochondrial homeostasis, and MT effectively restores the imbalance between mitochondrial fusion and fission, nucleus-encoded proteins, and improves ovarian reserve function through regulating P38 signaling pathway. These results indicate that targeting the P38 signaling pathway with MT could be a potential therapeutic strategy for treating DOR.

Autophagic flux-lipid droplet biogenesis cascade sustains mitochondrial fitness in colorectal cancer cells adapted to acidosis

Cancer development is associated with adaptation to various stressful conditions, such as extracellular acidosis. The adverse tumor microenvironment also selects for increased malignancy. Mitochondria are integral in stress sensing to allow for tumor cells to adapt to stressful conditions. Here, we show that colorectal cancer cells adapted to acidic microenvironment (CRC-AA) are more reliant on oxidative phosphorylation than their parental cells, and the acetyl-CoA in CRC-AA cells are generated from fatty acids and glutamine, but not from glucose. Consistently, CRC-AA cells exhibit increased mitochondrial mass and fitness that depends on an upregulated autophagic flux-lipid droplet axis. Lipid droplets (LDs) function as a buffering system to store the fatty acids derived from autophagy and to protect mitochondria from lipotoxicity in CRC-AA cells. Blockade of LD biogenesis causes mitochondrial dysfunction that can be rescued by inhibiting carnitine palmitoyltransferase 1 α (CPT1α). High level of mitochondrial superoxide is essential for the AMPK activation, resistance to apoptosis, high autophagic flux and mitochondrial function in CRC-AA cells. Thus, our results demonstrate that the cascade of autophagic flux and LD formation plays an essential role in sustaining mitochondrial fitness to promote cancer cell survival under chronic acidosis. Our findings provide insight into the pro-survival metabolic plasticity in cancer cells under microenvironmental or therapeutic stress and imply that this pro-survival cascade may potentially be targeted in cancer therapy.

Species variations in muscle stem cell-mediated immunosuppression on T cells

Muscle stem cells (MuSCs) are effective in treating inflammatory diseases driven by overactive innate immune responses, such as colitis and acute lung injury, due to their immunomodulatory properties. However, their potential in treating diseases driven by adaptive immune responses is still uncertain. When primed with inflammatory cytokines, MuSCs strongly suppressed T cell activation and proliferation in vitro in co-culture with activated splenocytes or peripheral blood mononuclear cells. Systemic administration of MuSCs from both mice and humans alleviated pathologies in mice with concanavalin A-induced acute liver injury, characterized by hyperactivated T lymphocytes. Importantly, MuSCs showed significant species-specific differences in their immunoregulatory functions. In mouse MuSCs (mMuSCs), deletion or inhibition of inducible nitric oxide synthase (iNOS) reduced their immunosuppressive activity, and absence of iNOS negated their therapeutic effects in liver injury. Conversely, in human MuSCs (hMuSCs), knockdown or inhibition of indoleamine 2,3-dioxygenase (IDO) eliminated their immunosuppressive effects, and loss of IDO function rendered hMuSCs ineffective in treating liver injury in mice. These results reveal significant species-specific differences in the mechanisms by which MuSCs mediate T cell immunosuppression. Mouse MuSCs rely on iNOS, while human MuSCs depend on IDO expression. This highlights the need to consider species-specific responses when evaluating MuSCs' therapeutic potential in immune-related disorders.

Engineering mesenchymal stem cells for premature ovarian failure: overcoming challenges and innovating therapeutic strategies

Premature ovarian failure (POF) is a leading cause of infertility in women, causing significant psychological and physical distress. Current therapeutic options are limited, necessitating the exploration of new treatments. Mesenchymal stem cells (MSCs), known for their remarkable homing and regenerative properties, have emerged as a promising intervention for POF. However, their clinical efficacy has been inconsistent. This paper aims to address these challenges by examining the cellular heterogeneity within MSC populations, which is crucial for identifying and selecting specific functional subpopulations for clinical applications. Understanding this heterogeneity can enhance therapeutic efficacy and ensure treatment stability. Additionally, this review comprehensively examines the literature on the effectiveness, safety, and ethical considerations of MSCs for ovarian regeneration, with a focus on preclinical and clinical trials. We also discuss potential strategies involving genetically and tissue-engineered MSCs. By integrating insights from these studies, we propose new directions for the design of targeted MSC treatments for POF and related disorders, potentially improving outcomes, addressing safety concerns, and expanding therapeutic options while ensuring ethical compliance.