DNA-based ForceChrono probes for deciphering single-molecule force dynamics in living cells.

Understanding cellular force transmission dynamics is crucial in mechanobiology. We developed the DNA-based ForceChrono probe to measure force magnitude, duration, and loading rates at the single-molecule level within living cells. The ForceChrono probe circumvents the limitations of in vitro single-molecule force spectroscopy by enabling direct measurements within the dynamic cellular environment. Our findings reveal integrin force loading rates of 0.5-2 pN/s and durations ranging from tens of seconds in nascent adhesions to approximately 100 s in mature focal adhesions. The probe's robust and reversible design allows for continuous monitoring of these dynamic changes as cells undergo morphological transformations. Additionally, by analyzing how mutations, deletions, or pharmacological interventions affect these parameters, we can deduce the functional roles of specific proteins or domains in cellular mechanotransduction. The ForceChrono probe provides detailed insights into the dynamics of mechanical forces, advancing our understanding of cellular mechanics and the molecular mechanisms of mechanotransduction.

Sequential CD7 CAR T-Cell Therapy and Allogeneic HSCT without GVHD Prophylaxis.

BACKGROUND: Patients with relapsed or refractory hematologic cancers have a poor prognosis. Chimeric antigen receptor (CAR) T-cell therapy as a bridge to allogeneic hematopoietic stem-cell transplantation (HSCT) has the potential for long-term tumor elimination. However, pre-HSCT myeloablation and graft-versus-host disease (GVHD) prophylaxis agents have toxic effects and could eradicate residual CAR T cells and compromise antitumor effects. Whether the integration of CAR T-cell therapy and allogeneic HSCT can preserve CAR T-cell function and improve tumor control is unclear. METHODS: We tested a novel "all-in-one" strategy consisting of sequential CD7 CAR T-cell therapy and haploidentical HSCT in 10 patients with relapsed or refractory CD7-positive leukemia or lymphoma. After CAR T-cell therapy led to complete remission with incomplete hematologic recovery, patients received haploidentical HSCT without pharmacologic myeloablation or GVHD prophylaxis drugs. Toxic effects and efficacy were closely monitored. RESULTS: After CAR T-cell therapy, all 10 patients had complete remission with incomplete hematologic recovery and grade 4 pancytopenia. After haploidentical HSCT, 1 patient died on day 13 of septic shock and encephalitis, 8 patients had full donor chimerism, and 1 patient had autologous hematopoiesis. Three patients had grade 2 HSCT-associated acute GVHD. The median follow-up was 15.1 months (range, 3.1 to 24.0) after CAR T-cell therapy. Six patients remained in minimal residual disease-negative complete remission, 2 had a relapse of CD7-negative leukemia, and 1 died of septic shock at 3.7 months. The estimated 1-year overall survival was 68% (95% confidence interval [CI], 43 to 100), and the estimated 1-year disease-free survival was 54% (95% CI, 29 to 100). CONCLUSIONS: Our findings suggest that sequential CD7 CAR T-cell therapy and haploidentical HSCT is safe and effective, with remission and serious but reversible adverse events. This strategy offers a feasible approach for patients with CD7-positive tumors who are ineligible for conventional allogeneic HSCT. (Funded by the National Natural Science Foundation of China and the Key Project of Science and Technology Department of Zhejiang Province; ClinicalTrials.gov numbers, NCT04599556 and NCT04538599.).

Hydrogel-based molecular tension fluorescence microscopy for investigating receptor-mediated rigidity sensing.

Extracellular matrix (ECM) rigidity serves as a crucial mechanical cue impacting diverse biological processes. However, understanding the molecular mechanisms of rigidity sensing has been limited by the spatial resolution and force sensitivity of current cellular force measurement techniques. Here we developed a method to functionalize DNA tension probes on soft hydrogel surfaces in a controllable and reliable manner, enabling molecular tension fluorescence microscopy for rigidity sensing studies. Our findings showed that fibroblasts respond to substrate rigidity by recruiting more force-bearing integrins and modulating integrin sampling frequency of the ECM, rather than simply overloading the existing integrin-ligand bonds, to promote focal adhesion maturation. We also demonstrated that ECM rigidity positively regulates the pN force of T cell receptor-ligand bond and T cell receptor mechanical sampling frequency, promoting T cell activation. Thus, hydrogel-based molecular tension fluorescence microscopy implemented on a standard confocal microscope provides a simple and effective means to explore detailed molecular force information for rigidity-dependent biological processes.

Fecal microbiota transplantation from young mice rejuvenates aged hematopoietic stem cells by suppressing inflammation.

Hematopoietic stem cell (HSC) aging is accompanied by hematopoietic reconstitution dysfunction, including loss of regenerative and engraftment ability, myeloid differentiation bias, and elevated risks of hematopoietic malignancies. Gut microbiota, a key regulator of host health and immunity, has recently been reported to affect hematopoiesis. However, there is currently limited empirical evidence explaining the direct impact of gut microbiome on aging hematopoiesis. In this study, we performed fecal microbiota transplantation (FMT) from young mice to aged mice and observed a significant increment in lymphoid differentiation and decrease in myeloid differentiation in aged recipient mice. Furthermore, FMT from young mice rejuvenated aged HSCs with enhanced short-term and long-term hematopoietic repopulation capacity. Mechanistically, single-cell RNA sequencing deciphered that FMT from young mice mitigated inflammatory signals, upregulated the FoxO signaling pathway, and promoted lymphoid differentiation of HSCs during aging. Finally, integrated microbiome and metabolome analyses uncovered that FMT reshaped gut microbiota composition and metabolite landscape, and Lachnospiraceae and tryptophan-associated metabolites promoted the recovery of hematopoiesis and rejuvenated aged HSCs. Together, our study highlights the paramount importance of the gut microbiota in HSC aging and provides insights into therapeutic strategies for aging-related hematologic disorders.

Anti-inflammatory roles of type I interferon signaling in the lung.

Excessive or persistent inflammation may have detrimental effects on lung structure and function. Currently, our understanding of conserved host mechanisms that control the inflammatory response remains incompletely understood. In this study, we investigated the role of type I interferon signaling in the inflammatory response against diverse clinically relevant stimuli. Using mice deficient in type I interferon signaling (IFNAR1-/-), we demonstrate that the absence of interferon signaling resulted in a robust and persistent inflammatory response against Pseudomonas aeruginosa, lipopolysaccharide, and chemotherapeutic agent bleomycin. The elevated inflammatory response in IFNAR1-/- mice was manifested as elevated myeloid cells, such as macrophages and neutrophils, in the bronchoalveolar lavage. The inflammatory cell response in the IFNAR1-/- mice persisted to 14 days and there is impaired recovery and fibrotic remodeling of the lung in IFNAR1-/- mice after bleomycin injury. In the Pseudomonas infection model, the elevated inflammatory cell response led to improved bacterial clearance in IFNAR1-/- mice, although there was similar lung injury and survival. We performed RNA sequencing of lung tissue in wild-type and IFNAR1-/- mice after LPS and bleomycin injury. Our unbiased analysis identified differentially expressed genes between IFNAR1-/- and wild-type mice, including previously unknown regulation of nucleotide-binding oligomerization domain (NOD)-like receptor signaling, retinoic acid-inducible gene-I (RIG-I) signaling, and necroptosis pathway by type I interferon signaling in both models. These data provide novel insights into the conserved anti-inflammatory mechanisms of the type I interferon signaling.NEW & NOTEWORTHY Type I interferons are known for their antiviral activities. In this study, we demonstrate a conserved anti-inflammatory role of type I interferon signaling against diverse stimuli in the lung. We show that exacerbated inflammatory response in the absence of type I interferon signaling has both acute and chronic consequences in the lung including structural changes.

Integrative multi-omics analysis identifies genetically supported druggable targets and immune cell specificity for myasthenia gravis.

BACKGROUND: Myasthenia gravis (MG) is a chronic autoimmune disorder characterized by fluctuating muscle weakness. Despite the availability of established therapies, the management of MG symptoms remains suboptimal, partially attributed to lack of efficacy or intolerable side-effects. Therefore, new effective drugs are warranted for treatment of MG. METHODS: By employing an analytical framework that combines Mendelian randomization (MR) and colocalization analysis, we estimate the causal effects of blood druggable expression quantitative trait loci (eQTLs) and protein quantitative trait loci (pQTLs) on the susceptibility of MG. We subsequently investigated whether potential genetic effects exhibit cell-type specificity by utilizing genetic colocalization analysis to assess the interplay between immune-cell-specific eQTLs and MG risk. RESULTS: We identified significant MR results for four genes (CDC42BPB, CD226, PRSS36, and TNFSF12) using cis-eQTL genetic instruments and three proteins (CTSH, PRSS8, and CPN2) using cis-pQTL genetic instruments. Six of these loci demonstrated evidence of colocalization with MG susceptibility (posterior probability > 0.80). We next undertook genetic colocalization to investigate cell-type-specific effects at these loci. Notably, we identified robust evidence of colocalization, with a posterior probability of 0.854, linking CTSH expression in TH2 cells and MG risk. CONCLUSIONS: This study provides crucial insights into the genetic and molecular factors associated with MG susceptibility, singling out CTSH as a potential candidate for in-depth investigation and clinical consideration. It additionally sheds light on the immune-cell regulatory mechanisms related to the disease. However, further research is imperative to validate these targets and evaluate their feasibility for drug development.

A rare KMT2A::CBL transcript in an acute monoblastic leukemia patient with an unfavorable outcome.

BACKGROUND: Lysine [K] methyltransferase 2A (KMT2A, previously known as MLL) gene rearrangements are common in acute leukemias of various lineages and are associated with features such as chemotherapy resistance and rapid relapse. KMT2A::CBL is a rare fusion of unknown pathogenesis generated by a unique interstitial deletion of chromosome 11 that has been reported across a wide age range in both acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) patients. The leukemogenic effect of the KMT2A::CBL rearrangement and its association with clinical prognosis have not been well clarified. METHODS AND RESULTS: We report the case of a 64-year-old female who was diagnosed with acute monoblastic leukemia (M5a) and who acquired the rare KMT2A::CBL fusion. The patient received multiple cycles of therapy but did not achieve remission and eventually succumbed to severe infection and disease progression. Additionally, we characterized the predicted KMT2A-CBL protein structure in this case to reveal the underlying leukemogenic mechanisms and summarized reported cases of hematological malignancies with KMT2A::CBL fusion to investigate the correlation of gene rearrangements with clinical outcomes. CONCLUSIONS: This report provides novel insights into the leukemogenic potential of the KMT2A::CBL rearrangement and the correlation between gene rearrangements and clinical outcomes.

The Impact of Parental Myopia and High Myopia on the Hyperopia Reserve of Preschool Children.

INTRODUCTION: The aim of this study was to explore the association between parental myopia and high myopia with children's refraction and ocular biometry in large-scale Chinese preschool children from the Beijing Hyperopia Reserve Study. SUBJECTS/METHODS: This cross-sectional kindergarten-based study enrolled children aged 3-6 years. Cycloplegic refraction, axial length (AL), and corneal radius (CR) were measured for all children. Parents were asked to complete a questionnaire about refractive status (no myopia, mild myopia <-3 D, moderate myopia ≥-3 D and ≤-6, and high myopia >-6 D). RESULTS: The study enrolled 2,053 children (1,069 boys and 984 girls), with a mean age of 4.26 ± 0.96 years and mean spherical equivalent refraction (SER) of 1.11 ± 0.97 diopter. Of the children, 90.7% had at least one myopic parent, and 511 children (24.9%) had at least one highly myopic parent. SER decreased significantly with increasing severity of parental myopia (p < 0.001). Preschool children's myopia was independently associated with parental myopia (OR, 10.4 and 11.5 for one and two highly myopic parent[s]). Age (OR = 1.1), gender (OR = 1.7; girls as references), near work time (OR = 1.2), and both maternal (OR, 1.4 and 2.0 for moderate and high myopia) and paternal myopia (OR, 1.6 and 1.9 for moderate and high myopia) were independent risk factors for lacking hyperopia reserve. CONCLUSION: Severe parental myopia was associated with a lower SER, longer AL, and higher AL/CR ratio in preschool children. Parental myopia and near work may predispose children to faster elimination of hyperopia reserves before exposure to higher educational stress.

Small nucleolar RNA host gene 5 plays a role in orthodontic tooth movement by inhibiting osteoclast differentiation.

BACKGROUND AND OBJECTIVES: The alveolar bone remodelling promoted by reasonable mechanical force triggers orthodontic tooth movement (OTM). The generation of osteoclasts is essential in this process. However, the mechanism of mechanical force mediating osteoclast differentiation remains elusive. Small nucleolar RNA host gene 5 (SNHG5), which was reported to mediate the osteogenic differentiation of bone marrow mesenchymal stem cells in our previous study, was downregulated in human periodontal ligament cells (hPDLCs) under mechanical force. At the same time, the RANKL/OPG ratio increased. Based on this, we probed into the role of SNHG5 in osteoclast formation during OTM and the relevant mechanism. MATERIALS AND METHODS: SNHG5 and the RANKL/OPG ratio under different compressive forces were detected by western blotting (WB) and qRT-PCR. Impact of overexpression or knockdown of SNHG5 on osteoclast differentiation was detected by qRT-PCR, WB and transwell experiments. The combination of SNHG5 and C/EBPß was verified by RNA immunoprecipitation and RNA pull-down assays. The expression of SNHG5 and osteoclast markers in gingiva were analysed by qRT-PCR and the paraffin sections of periodontal tissues were used for histological analysis. RESULTS: Compressive force downregulated SNHG5 and upregulated the RANKL/OPG ratio in hPDLCs. Overexpression of SNHG5 inhibited RANKL's expression and osteoclast differentiation. SNHG5 combined with C/EBPß, a regulator of osteoclast. The expression of SNHG5 in periodontal tissue decreased during OTM. CONCLUSION: SNHG5 inhibited osteoclast differentiation during OTM, achieved by affecting RANKL secretion, which may provide a new idea to interfere with bone resorption during orthodontic treatment.

Pancreatic Cancer: An Exocrine Tumor with Endocrine Characteristics.

OBJECTIVE: To examine the characteristics of pancreatic cancer patients with long-term survival. BACKGROUND: Although pancreatic cancer is a highly lethal malignancy, a minority of patients experience long-term survival. The characteristics of these patients remain largely unidentified. METHODS: An indolent subgroup was established using carbohydrate antigen 19-9 (CA19-9), which is the best-validated biomarker for pancreatic cancer. Of 1558 patients, 13.9% were included in the CA19-9-normal (≤ 37 U/mL) subgroup. RESULTS: A normal A19-9 level was an independent variable for overall survival (median survival, 18.1 vs. 9.7 months, hazard ratio = 0.53, P < 0.001). The 5-year survival of patients with stage IV CA19-9-normal cancer was higher than that of patients with stage I-IV CA19-9-high cancer (22.4% vs. 6.8%, P = 0.034). The CA19-9-normal subgroup exhibited reduced levels of circulating glucose (P < 0.001) and increased expression of insulin (P < 0.001) compared with the CA19-9-high subgroup. Glucose was a substrate for CA19-9 biosynthesis through the hexosamine biosynthesis pathway. In addition, in pancreatic cancer animal models of diabetes, glucose control decreased CA19-9 levels and improved overall survival. In a clinical trial (NCT05306028) of patients before undergoing major anticancer treatments, glucose control decreased CA19-9 levels in 90.9% of the patients. CONCLUSIONS: CA19-9-normal pancreatic cancer is a strikingly indolent subgroup with low glucose and high insulin. Glucose control is a promising therapeutic strategy for pancreatic cancer.

Transfer of miR-4755-5p through extracellular vesicles and particles induces decitabine resistance in recipient cells by targeting CDKN2B.

Decitabine (5-aza-2-deoxycytidine, DAC), a DNA-hypomethylating agent, has been one of the frontline therapies for clonal hematopoietic stem cell disorders, such as myelodysplastic syndrome and acute myeloid leukemia, but DAC-resistance often occurs and leads to treatment failure. Therefore, elucidating the mechanisms of DAC resistance is important for improving its therapeutic efficacy. The extracellular vesicles and particles (EVPs) have been reported to be involved in mediating drug resistance by transporting diverse bioactive components. In this study, we established the DAC-resistant cell line (KG1a-DAC) from its parental human leukemia-derived cell line KG1a and observed that EVPs released from KG1a-DAC can promote DAC-resistant in KG1a cells. Moreover, treatment with KG1a-DAC EVPs reduced the expression of cyclin-dependent kinase inhibitor 2B (CDKN2B) in KG1a cells. miRNA-Seq analysis revealed that miR-4755-5p is overexpressed in EVPs from KG1a-DAC. Dual-luciferase reporter assay and flow cytometry analysis confirmed that miR-4755-5p rendered KG1a cells resistant to the DAC by targeting CDKN2B gene. Taken together, miR-4755-5p in EVPs released from the DAC-resistant cells plays an essential role in inducing DAC-resistance, and is a potential therapeutic target for suppression of DAC resistance.

Systems pharmacology approach to explore the mechanisms of shufeng Jiedu Capsule on treating H1N1 infection.

BACKGROUND: Influenza caused by the H1N1 virus still affects human health. There is currently no effective strategy against H1N1 virus infection. The present study is to evaluate the mechanism of Shufeng Jiedu Capsule (SFJDC) in the treatment of H1N1 infection using an integrated systems pharmacology approach and experimental validation. SFJDC is recommended for the treatment of H1N1 infection in traditional Chinese medicine (TCM), whose mechanism of action is not precise. METHODS: We systematically analyzed SFJDC using a systematic pharmacology and ADME screening model, and predicted effective targets using systematic drug targeting (SysDT) algorithm. Subsequently, the network of interactions between compounds and targets was built to help in the discovery of new drugs. In addition, the pathway of molecular action was determined by using enrichment analysis from the predicted targets. what is more, molecular docking also applied to predict the specific binding sites and binding capacity of active compounds and related targets, which validated the results of the compounds-targets network (C-T network). Finally, the mechanism of SFJDC effect on autophagy and virus replication in H1N1 virus-infected RAW264.7 mouse macrophage cells was experimentally verified. RESULTS: The systematic pharmacology results suggested that 68 candidate compounds were obtained from SFJDC, which interacted with 74 different targets related to inflammation and the immune system. The CCK-8 results showed that different concentrations of SFJDC serum had no significant inhibitory effect on the viability of RAW264.7 cells. LC3-II was significantly increased after virus infection compared to the control group, while it was inhibited by different concentrations of SFJDC serum. H1N1 virus nucleocapsid protein (NP protein) was significantly reduced in the high concentration group, Interleukin-1ß (IL-1ß), Interleukin-6 (IL-6), Tumor Necrosis Factor-α (TNF-α), and viral M1 gene were significantly reduced compared to the H1N1 group. CONCLUSIONS: The integrated systemic pharmacological approach and experimental validation not only provide a precise explanation of the molecular mechanism of SFJDC in the treatment of H1N1 infection but also provide valuable clues for the development of novel drug strategies to control the H1N1 infection.

iNKT cells with high PLZF expression are recruited into the lung via CCL21-CCR7 signaling to facilitate the development of asthma tolerance in mice.

Establishment of immune tolerance is crucial to protect humans against asthma. Promyelocytic leukemia zinc finger (PLZF) is an emerging suppressor of inflammatory responses. CCL21-CCR7 signaling mediates tolerance development. However, whether PLZF and CCL21-CCR7 are required for the development of asthma tolerance is unknown. Here, we found that Zbtb16 (coding PLZF) and Ccl21 were upregulated in OVA-induced asthma tolerance (OT) lungs by RNA-seq. PLZF physically interacted with GATA3 and its expression was higher in GATA3+ Th2 cells and ILC2s in OT lungs. Zbtb16-knockdown in lymphocytes promoted the differentiation of CD3e+ CD4+ T cells, particularly those producing IL-4 and IL-5. Moreover, iNKT cells with high expression of PLZF were recruited into the lungs via draining lymph nodes during tolerance. Blockade of CCL21-CCR7 signaling in OT mice decreased the PLZF+  cell population, abolished CCR7-induced PLZF+ iNKT recruitment to the lungs, enhanced Th2responses and exacerbated lung pathology. In OT mice, respiratory syncytial virus (RSV) infection impeded PLZF+  cell and CCR7+ PLZF+ iNKT cellrecruitment to the lungs and increased airway resistance. Collectively, these results indicate that PLZF could interact with GATA3 and restrain differentiation of IL-4- and IL-5-producing T cells, iNKT cells with high PLZF expression are recruited to the lungs via CCL21-CCR7 signaling to facilitate the development of asthma tolerance.

Emissions of Liquid Crystal Monomers from Obsolete Smartphone Screens in Indoor Settings: Characteristics and Human Exposure Risk.

Liquid crystal monomers (LCMs) have been found to accumulate in indoor environments, but the emission kinetics of LCMs from electronic devices are not well understood. Leakage from damaged liquid crystal displays may be an important mechanism for LCMs to enter the environment and become potential health hazards to humans. To address this issue, we conducted chamber experiments to characterize the emissions of LCMs from obsolete smartphone screens and estimated the doses of residential and occupational exposures to LCMs. The emission rates of the detected LCMs were in the ranges of 0.1-7 µg m-2 h-1 at 80 °C, 0.05-7 µg m-2 h-1 at 60 °C, and 0.002-0.2 µg m-2 h-1 at 25 °C. Liquid crystal monomers with large molecular weights and low volatilities tended to accumulate at screen surfaces and were re-emitted at elevated temperatures, leading to high emission rates of heavy LCMs upon thermal treatment. The estimated doses of residential and occupational exposures to individual LCMs were 0.0001-0.009 and 0.007-2 ng kg-1 d-1, respectively. As LCMs are potentially carcinogenic based on in silico assessments, LCMs emitted from obsolete smartphones in indoor settings may become human health hazards.

Long noncoding RNA GAS5 attenuates cigarette smoke-induced airway remodeling by regulating miR-217-5p/PTEN axis.

Airway remodeling is a remarkable pathological characteristic of chronic obstructive pulmonary disease (COPD), and long noncoding RNAs have been demonstrated to participate in COPD development and pathogenesis. Here, we investigate the role of long noncoding RNA GAS5 in cigarette smoke (CS)-induced airway remodeling. GAS5 expression is significantly lower in lung tissues of CS-exposed mice than in tissues of control mice without exposure to CS. Forced GAS5 overexpression suppresses CS-induced airway inflammation and remodeling. GAS5 overexpression also inhibits CS extract-induced inflammatory-cytokine expression and fibroblast activation in vitro. Regarding the mechanism, GAS5 acts as a sponge of miR-217-5p, thereby increasing PTEN expression. MiR-217-5p overexpression and PTEN knockdown separately reverse the inhibitory effects of GAS5 overexpression on the inflammatory-cytokine expression and fibroblast activation. Collectively, these results suggest that GAS5 can suppress airway inflammation and fibroblast activation by regulating miR-217-5p/PTEN axis, which may help develop novel therapeutic strategies against COPD.

LncRNA IGF2-AS promotes endometriosis progression through targeting miR-370-3p/IGF2 axis and activating PI3K/AKT/mTOR signaling pathway.

PURPOSE: Endometriosis, a gynecological disease, is difficult to be cured. Currently, to identify more potential biomarkers for the early diagnosis of endometriosis is urgently needed. Insulin like growth factor 2 (IGF2) has been revealed to correlate with endometriosis. This research aimed to further explore the role of IGF2 and its up-stream mechanism in endometriosis. METHODS: Primary ectopic endometrial stromal cells (EESCs) were extracted from ectopic endometrial tissues which were pathological endometrial tissues resected from three patients with II-III endometriosis. Primary normal endometrial stromal cells (NESCs) were extracted from normal endometrial tissues of two patients with grade III cervical dysplasia and one patient with uterine leiomyoma III. Four endometriotic cell lines (EEC145T, hEM15A, hEM5B2, and 12Z) and normal human endometrial epithelial cells (hEECs) were purchased. Cell proliferation, migration, and invasion were evaluated through functional assays. The molecular interaction between RNAs was investigated through mechanistic analyses. RESULTS: We discovered that IGF2 was upregulated in purchased endometriotic cells and primary EESC. Suppression of IGF2 hampered cell proliferation, migration, and invasion. Furthermore, insulin-like growth factor 2 antisense RNA (IGF2-AS) was uncovered to positively regulate IGF2 expression and enhanced proliferative, migratory, and invasive abilities of endometriotic cells. Mechanistically, miR-370-3p was found to bind with IGF2-AS and IGF2. IGF2-AS competitively bind with miR-370-3p to upregulate IGF2. Furthermore, IGF2-AS was revealed to activate the PI3K/AKT/mTOR signaling pathway through targeting miR-370-3p/IGF2 axis. CONCLUSION: IGF2-AS promotes endometriotic cell growth via regulating IGF2/miR-370-3p axis and further activating PI3K/AKT/mTOR signaling pathway.

Astragaloside IV improved antioxidative stress capacity and related gene expression of the Keap1-Nrf2 pathway in grass carp (Ctenopharyngodon idella) hepatocytes under heat stress.

This study aims to investigate the protective effects of astragaloside IV (AS-IV) on the hepatocytes of grass carp (Ctenopharyngodon idella) on heat stress. Cultured cells were treated with AS-IV (0, 50, 100 and 200 µg/ml) at 28°C for 24 h and then exposed to heat stress by increasing the culturing temperature (32 ± 0.5°C) for 6 h. The increased temperatures significantly reduced cell viability and superoxide dismutase (SOD) activity, and increased malondialdehyde (MDA) levels in the 0 µg/ml AS-IV treatment group at 32°C, but the grass carp hepatocytes treated with 100 and 200 µg/ml AS-IV had significantly increased cell viability and SOD activity and decreased MDA levels. The mRNA levels of keap1a, keap1b, nrf2, gsh-px, cat, cu-zn sod, mgst1 and il-6 were significantly lower in the 0 µg/ml AS-IV treatment group at 32°C, while those of keap1a, nrf2, gsh-px, cat, cu-zn sod, gstp1, ho-1 and il-6 were significantly higher in cells treated with 100 or 200 µg/ml AS-IV. Our findings indicate that AS-IV could enhance the antioxidative stress capacity of grass carp hepatocytes under heat stress, and its mechanism may be associated with the activation of the Keap1-Nrf2 pathway. Thus, these results provide new insights into how to alleviate heat stress in grass carp.

Vagal-α7nAChR signaling attenuates allergic asthma responses and facilitates asthma tolerance by regulating inflammatory group 2 innate lymphoid cells.

Disorders of immune tolerance may lead to allergic asthma. Group 2 innate lymphoid cells (ILC2s) and inflammatory ILC2s (iILC2s) are key players in asthma. The vagus nerve innervating the airways releases acetylcholine or neuropeptides (i.e. calcitonin gene-related peptide) via pulmonary C-fibers (PCFs), which could regulate ILC2 activity upon binding the α7 nicotinic acetylcholine receptor (α7nAChR, coded by Chrna7) or neuropeptide receptors. Whether and how α7nAChR and PCFs regulate asthma and the formation of asthma tolerance via ILC2s or iILC2s are poorly understood. We used vagotomized, PCF degeneration and Chrna7 knockout mice to investigate ovalbumin (OVA)-induced asthma and oral OVA feeding-induced asthma tolerance. Our results revealed that vagotomy could generally suppress lung ILC2s and iILC2s, which mitigated allergic asthma responses but disrupted asthmatic tolerance. Removal of neuropeptides by PCF degeneration also reduced lung ILC2s and iILC2s, attenuating asthma responses, but did not affect asthma tolerance. In comparison, deletion of Chrna7 increased resident ILC2s and trafficking iILC2s in the lung, worsened allergic inflammation and disrupted oral tolerance. Mechanistically, deletion of Chrna7 in asthma-tolerant conditions upregulated T helper 2 cytokine- (Il4, Il13 and Il25) and sphingosine-1-phosphate (S1P)-related genes (S1pr1 and Sphk1). Blockade of S1P reduced iILC2 recruitment into asthmatic lungs. Our work is the first to demonstrate that vagal-α7nAChR signaling engaging with iILC2s and S1P not only alleviates asthma but also facilitates asthma tolerance. These findings may provide a novel therapeutic target for attenuating asthma by enhancing asthmatic tolerance.

Th17/Treg cell imbalance plays an important role in respiratory syncytial virus infection compromising asthma tolerance in mice.

Mucosal tolerance is induced early in life and is an important mechanism of protection from diseases, such as asthma. Respiratory syncytial virus (RSV) is a main cause of bronchiolitis and pneumonia in infants. Clinical studies have found that there is a strong association between RSV infection in infancy and later development of asthma, but the underlying mechanisms are unclear. A mouse model of immune tolerance induced by oral feeding of ovalbumin(OVA) was successfully established in our previous studies. We found that RSV infection could break the oral immune tolerance state.RSV infection increased the mRNA expression of IL-17A and IL-17A/Foxp3(the transcription factor forkhead box P3) in OT mice, but the mRNA expression of IL-4 and other T helper(Th)2 cytokines did not change significantly. As detected by flow cytometry analysis, RSV infection elevated Th17 cell levels and correspondingly decreased Regulatory T(Treg) cell levels in the hilar lymph nodes (HLNs) and mesenteric lymph nodes (MLNs), but there were no significant differences in the spleen or peripheral blood.We hypothesized that an imbalance in Th cells played an important role in RSV infection compromising asthma tolerance.RSV infection disrupted asthma tolerance by increasing the Th17/Treg ratio rather than the Th1/Th2 ratio'.Therefore, altering the Th17/Treg ratio has been identified as a potential therapeutic target in asthma caused by RSV or another virus.

The oncometabolite R-2-hydroxyglutarate dysregulates the differentiation of human mesenchymal stromal cells via inducing DNA hypermethylation.

BACKGROUND: Isocitrate dehydrogenase (IDH1/2) gene mutations are the most frequently observed mutations in cartilaginous tumors. The mutant IDH causes elevation in the levels of R-enantiomer of 2-hydroxylglutarate (R-2HG). Mesenchymal stromal cells (MSCs) are reasonable precursor cell candidates of cartilaginous tumors. This study aimed to investigate the effect of oncometabolite R-2HG on MSCs. METHODS: Human bone marrow MSCs treated with or without R-2HG at concentrations 0.1 to 1.5 mM were used for experiments. Cell Counting Kit-8 was used to detect the proliferation of MSCs. To determine the effects of R-2HG on MSC differentiation, cells were cultured in osteogenic, chondrogenic and adipogenic medium. Specific staining approaches were performed and differentiation-related genes were quantified. Furthermore, DNA methylation status was explored by Illumina array-based arrays. Real-time PCR was applied to examine the signaling component mRNAs involved in. RESULTS: R-2HG showed no influence on the proliferation of human MSCs. R-2HG blocked osteogenic differentiation, whereas promoted adipogenic differentiation of MSCs in a dose-dependent manner. R-2HG inhibited chondrogenic differentiation of MSCs, but increased the expression of genes related to chondrocyte hypertrophy in a lower concentration (1.0 mM). Moreover, R-2HG induced a pronounced DNA hypermethylation state of MSC. R-2HG also improved promotor methylation of lineage-specific genes during osteogenic and chondrogenic differentiation. In addition, R-2HG induced hypermethylation and decreased the mRNA levels of SHH, GLI1and GLI2, indicating Sonic Hedgehog (Shh) signaling inhibition. CONCLUSIONS: The oncometabolite R-2HG dysregulated the chondrogenic and osteogenic differentiation of MSCs possibly via induction of DNA hypermethylation, improving the role of R-2HG in cartilaginous tumor development.