Molecular Medicine最新文献

Aims: Atrial fibrillation (AF) has high mortality and morbidity rates. However, the intracellular molecular complexity of the atrial tissue of patients with AF has not been adequately assessed.

Methods and results: We investigated the cellular heterogeneity of human atrial tissue and changes in differentially expressed genes between cells using single-cell RNA sequencing, fluorescence in situ hybridization, intercellular communication, and cell trajectory analysis. Using genome-wide association studies (GWAS) and proteomics, we discovered cell types enriched for AF susceptibility genes. We discovered eight different cell types, which were further subdivided into 23 subpopulations. In AF, the communication strength between smooth muscle cells (SMCs) and fibroblast (FB) 3 cells increased and the relevant signaling pathways were quite similar. Subpopulations of endothelial cells (ECs) are mainly involved in fibrosis through TXNDC5 and POSTN. AF susceptibility genes revealed by GWAS were especially enriched in neuronal and epicardial cells, FB3, and lymphoid (Lys) cells, whereas proteomic sequencing differential proteins were concentrated in FB3 cells and SMCs.

Conclusions: This study provides a cellular landscape based on the atrial tissue of patients with AF and highlights intercellular changes and differentially expressed genes that occur during the disease process. A thorough description of the cellular populations involved in AF will facilitate the identification of new cell-based interventional targets with direct functional significance for the treatment of human disease.

In the mammalian brain, new neurons continue to be generated throughout life in a process known as adult neurogenesis. The role of adult-generated neurons has been broadly studied across laboratories, and mounting evidence suggests a strong link to the HPA axis and concomitant dysregulations in patients diagnosed with mood disorders. Psychedelic compounds, such as phenethylamines, tryptamines, cannabinoids, and a variety of ever-growing chemical categories, have emerged as therapeutic options for neuropsychiatric disorders, while numerous reports link their effects to increased adult neurogenesis. In this systematic review, we examine studies assessing neurogenesis or other neurogenesis-associated brain plasticity after psychedelic interventions and aim to provide a comprehensive picture of how this vast category of compounds regulates the generation of new neurons. We conducted a literature search on PubMed and Science Direct databases, considering all articles published until January 31, 2023, and selected articles containing both the words "neurogenesis" and "psychedelics". We analyzed experimental studies using either in vivo or in vitro models, employing classical or atypical psychedelics at all ontogenetic windows, as well as human studies referring to neurogenesis-associated plasticity. Our findings were divided into five main categories of psychedelics: CB1 agonists, NMDA antagonists, harmala alkaloids, tryptamines, and entactogens. We described the outcomes of neurogenesis assessments and investigated related results on the effects of psychedelics on brain plasticity and behavior within our sample. In summary, this review presents an extensive study into how different psychedelics may affect the birth of new neurons and other brain-related processes. Such knowledge may be valuable for future research on novel therapeutic strategies for neuropsychiatric disorders.

Background: Triolein, a symmetric triglyceride exhibiting anti-inflammatory and antioxidant properties, has demonstrated potential in mitigating cellular damage. However, its therapeutic efficacy in ischemic stroke (IS) and underlying molecular mechanisms remain elusive. Given the critical roles of inflammation and autophagy in IS pathogenesis, this study aimed to elucidate the effects of triolein in IS and investigate its mechanism of action.

Methods: We evaluated the impact of triolein using both in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) and in vivo middle cerebral artery occlusion (MCAO/R) models. Neurological function and cerebral infarct volume were assessed 72 h post-reperfusion. Autophagy was quantified through monodansyl cadaverine (MDC) labeling of autophagic vesicles and Western blot analysis of autophagy-related proteins. Microglial activation was visualized via immunofluorescence, while inflammatory cytokine expression was quantified using RT-qPCR. The cytoprotective effect of triolein on OGD/R-induced HT22 cells was evaluated using Cell Counting Kit-8 and lactate dehydrogenase release assays. The involvement of the Protein kinase B/Mechanistic target of rapamycin kinase (AKT/mTOR) pathway was assessed through Western blot analysis.

Results: Triolein administration significantly reduced infarct volume, enhanced neurological recovery, and attenuated M1 microglial activation and inflammation in MCAO/R-induced mice. Western blot analysis and MDC labeling revealed that triolein exerted an inhibitory effect on post-IS autophagy. Notably, in the BV2-induced OGD/R model, triolein demonstrated an autophagy-dependent suppression of the inflammatory response. Furthermore, triolein inhibited the activation of the AKT/mTOR signaling pathway, consequently attenuating autophagy and mitigating the post-IS inflammatory response.

Conclusions: This study provides novel evidence that triolein exerts neuroprotective effects by inhibiting post-stroke inflammation through an autophagy-dependent mechanism. Moreover, the modulation of the AKT/mTOR signaling pathway appears to be integral to the neuroprotective efficacy of triolein. These findings elucidate potential therapeutic strategies for IS management and warrant further investigation.

Background: Extragonadal follicle-stimulating hormone receptor (FSHR) expression at low levels has been shown in several normal and tumor tissues, including myometrium and adipose tissue. FSH-FSHR signaling in the myometrium has been suggested to regulate uterine contractile activity and the timing of labor. In contrast, FSH-FSHR has been linked to the activation of brown/beige fat thermogenesis in adipose tissue. The issue of extragonadal FSHR expression and its functionality remains contentious within the scientific community, as contradictory findings necessitate further independent and critical analyses. Hereby, we re-investigated the FSHR expression and its functionality in normal non-pregnant (M-NP) and pregnant (N-P) human myometrium, as well as in human visceral (VAT) and subcutaneous (SCAT) adipose tissue (AT).

Methods: FSHR expression at mRNA (real-time qPCR, RNAscope in situ hybridization) and protein (immunohistochemical staining) levels in adipose tissue, myometrium, and adipocytes were evaluated. Myometrium and adipocytes were treated with recombinant (rh)FSH to study its effects on functional pathways. Myometrium contractile activity was measured using a force transducer with digital output and the DASYLab software unit. Cyclic adenosine monophosphate (cAMP) production by myometrium explants and adipocytes was measured using a cAMP ELISA Kit. The activation of the AKT pathway in myometrium and adipocytes was analyzed by Western blot analysis.

Results: Contrary to previous observations, we found no expression of FSHR at either mRNA or protein levels in M-NP, N-P, VAT, and SCAT. Treatment with recombinant human FSH (rhFSH) showed no effect on cAMP production or phosphorylation of AKT in M-NP, N-P, as well as in VAT and SCAT. rhFSH treatment did not influence contractile activity in M-NP, N-P.

Conclusions: These findings suggest that the FSHR signaling pathway does not regulate myometrial contractility during pregnancy. Additionally, the absence of FSHR expression in both VAT and SCAT implied that FSHR does not play a role in the functional signaling pathways in adipose tissues. In conclusion, our findings contradict earlier data on the involvement of FSH-FSHR signaling in regulating myometrial contractility near term, as well as in adipose tissue function.

Background: Rotator cuff tears (RCTs) are among the most common musculoskeletal disorders that affect quality of life. This study aimed to investigate the efficacy of ginsenoside Rb1 in RCTs and the mechanisms involved.

Methods: First, a fibrotic model of FAPs was induced, and FAPs were cultured in media supplemented with different concentrations of ginsenoside Rb1. Next, a rat model of RCTs was constructed and treated with ginsenoside Rb1. Molecular docking was subsequently utilized to detect the binding of ginsenoside Rb1 and SFRP1. Finally, SFRP1 was knocked down and overexpressed in vivo and in vitro to investigate the mechanism of ginsenoside Rb1 and SFRP1 in RCTs.

Results: Compared with the Normal group, FAP viability was decreased, but Collagen II, FN and α-SMA levels were increased in the Control group. After treatment with different concentrations of ginsenoside Rb1, FAP viability increased, but Collagen II, FN and α-SMA levels decreased. Among them, 60 µM ginsenoside Rb1 had the best effect. In vivo experiments revealed that ginsenoside Rb1 improved RCTs in rats. Molecular docking revealed the binding of ginsenoside Rb1 to SFRP1. Additionally, SFRP1 levels were lower in the Control group than in the Normal group. After treatment with ginsenoside Rb1, SFRP1 levels increased. In vivo, overexpressing SFRP1 along with ginsenoside Rb1 treatment further alleviated tendon tissue fibroblast infiltration and fat accumulation and further reduced the expression of Collagen II, FN, and α-SMA. In vitro, overexpressing SFRP1 along with ginsenoside Rb1 treatment further decreased the expression of CaMKII, PLC, PKC, Wnt, and β-catenin, further decreased the Ca²⁺ fluorescence intensity and mitochondrial length, increased the red/green intensity, and decreased the MitoSOX fluorescence intensity. Additionally, overexpressing SFRP1 along with ginsenoside Rb1 treatment further increased cell proliferation, decreased apoptosis, reduced the protein expression of Collagen II, FN, and α-SMA in muscle tissue, and further reduced the levels of TNF-α, IL-1β, and IL-6 in the cell supernatant.

Conclusions: Ginsenoside Rb1 inhibited the activation of the Wnt signaling pathway by promoting SFRP1 expression, thereby inhibiting mitochondrial function and Ca²⁺ absorption to treat fat infiltration and muscle fibrosis caused by RCTs.

Background: Evidence has shown that oxidative stress induced by high glucose microenvironment in placenta of gestational diabetes mellitus (GDM) is indispensable to the progression of this condition. Adipokine chemerin was linked with GDM, yet the roles of chemerin in placental oxidative stress and its underlying effects on GDM in vivo remain elusive.

Methods: We firstly analyzed the disparities of oxidative stress levels in placenta between GDM and normoglycaemic pregnant women, and then added recombinant active chemerin to the high-glucose treated human trophoblastic cells to investigate effects of chemerin on reactive oxygen species (ROS), total antioxidant capacity (T-AOC) and intake of glucose. Finally, a GDM animal model induced by high-fat diet (HFD) was established and the impacts of chemerin on oxidative stress of placenta and fetal growth of GDM were explored.

Results: Analysis of human samples showed that the extent of lipid peroxidation in placenta was significantly elevated in GDM patients compared with their normoglycaemic counterparts. In the high glucose cell model, active chemerin lessened the content of ROS, heightened the index of T-AOC and stimulated glucose uptake in a concentration-dependent manner. Importantly, we successfully constructed a GDM mouse model through HFD. The treatment of chemerin was found to alleviate the high blood glucose levels in these HFD-fed pregnant mice and attenuate the excessive growth of their offspring. Our data also revealed that chemerin might counteract placental oxidative stress in HFD mice by improving the activity of superoxide dismutase.

Conclusions: The present study further elucidated the molecular biology of chemerin, which plays a pivotal role in ameliorating oxidative stress and hyperglycemia, resulting in improved fetal overgrowth in GDM.

The fibrogenic conversion of satellite cells contributes to the atrophy and fibrosis of skeletal muscle, playing a significant role in the pathogenesis of age-related sarcopenia. Melatonin, a hormone secreted by the pineal gland, exhibits anti-aging and anti-fibrotic effects in various conditions. However, the effect of melatonin on satellite cell fate and age-related sarcopenia remains under-explored. Here, we report that melatonin treatment mitigated the loss of muscle mass and strength in aged mice, replenished the satellite cell pool and curtailed muscle fibrosis. When primary SCs were cultured in vitro and subjected to aging induction via D-galactose, they exhibited a diminished myogenic potential and a conversion from myogenic to fibrogenic lineage. Notably, melatonin treatment effectively restored the myogenic potential and inhibited this lineage conversion. Furthermore, melatonin attenuated the expression of the fibrogenic cytokine, transforming growth factor-β1, and reduced the phosphorylation of its downstream targets Smad2/3 both in vivo and in vitro. In summary, our findings show melatonin's capacity to counteract muscle decline and inhibit fibrogenic conversion in aging SCs and highlight its potential therapeutic value for age-related sarcopenia.

Rheumatoid arthritis (RA) is a common autoimmune disease that can lead to irreversible joint damage when it occurs, but its pathogenesis has not yet been elucidated. In this study, we explored the roles of macrophage migration inhibitory factor (MIF), endoplasmic reticulum stress (ER stress), and Th17 cells in the pathogenesis of RA. We have preliminarily confirmed that MIF expression in CD4⁺T cells and the proportion of Th17 cells are increased in active RA patients. We also found that ER stress is activated, initiating ATF6 pathway in the UPR. Additionally, using in vitro stimulation and co-immunoprecipitation experiments, we have confirmed the interaction between MIF and ATF6, which enhances protein expression in ATF6 pathway. Subsequently, in the chromatin immunoprecipitation assay, we observed the enrichment of ATF6 subunit on the promoter sequences of the Th17 cell differentiation genes STAT3 and RORC. Additionally, the differentiation of Th17 cells was disrupted by Ceapin-A7 (ATF6 inhibitor). In summary, our results indicate that MIF enhances ATF6 pathway signaling, which promotes the differentiation of Th17 cells. This could be a potential mechanism underlying the pathogenesis of RA, offering a new direction for the clinical treatment of RA.

Background: Polycomb proteins are conventionally known as global repressors in cell fate determination. However, recent observations have shown their involvement in transcriptional activation, the mechanisms of which need further investigation.

Methods: Herein, multiple data from ChIP-seq, RNA-seq and HiChIP before or after RYBP depletion in embryonic stem cell (ESC), epidermal progenitor (EPC) and mesodermal cell (MEC) were analyzed.

Results: We found that Polycomb protein RYBP occupies super-enhancer (SE) in ESCs, where core Polycomb group (PcG) components such as RING1B and EZH2 are minimally enriched. Depletion of RYBP results in impaired deposition of H3K27ac, decreased expression of SE-associated genes, and reducing the transcription of enhancer RNA at SE regions (seRNA). Regarding the mechanism of seRNA transcription, the Trithorax group (TrxG) component WDR5 co-localizes with RYBP at SEs, and is required for seRNA expression. RYBP depletion reduces WDR5 deposition at SE regions. In addition, TrxG-associated H3K4me3 tends to be enriched at SEs with high levels of seRNA transcription, and RYBP deficiency impairs the deposition of H3K4me3 at SEs. Structurally, RYBP is involved in both intra- and inter-SE interactions. Finally, RYBP generally localizes at SEs in both in vitro cell lines and in vivo tissue-derived cells, dysfunction of RYBP is associated with various cancers and developmental diseases.

Conclusion: RYBP cooperates with TrxG component to regulate SE activity. Dysfunction of RYBP relates to various diseases. The findings provide new insights into the transcriptionally active function of Polycomb protein in cell fate determination.

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common liver disease worldwide and few drugs are available for its treatment. Lycorine has effective anti-inflammatory and lipid-lowering effects, but the impact on MASLD is not fully understood. In this study, we intend to test the intervention effect of lycorine on MASLD.

Methods: A MASLD mouse model was constructed on a high-fat diet for 16 weeks, and low, medium, and high doses of lycorine were given by gavage for the last 4 weeks. Detecting indicators related to liver steatosis, oxidative stress, and ferroptosis. In vivo and in vitro experiments co-validate potential targets identified by network pharmacology, molecular docking and western blot for lycorine intervention in MASLD liver. A combination of pathology, western blot, qRT-PCR, and 16 S rRNA sequencing verified adipose tissue and intestinal alterations.

Results: Lycorine ameliorated hepatic steatosis, oxidative stress and ferroptosis in MASLD mice by inhibiting the expression of phosphorylated EGFR, inhibiting the PI3K/AKT signaling pathway. We also observed a dose-dependent effect of lycorine to improve some of the indicators of MASLD. In vitro, knockdown of EGFR significantly attenuated palmitic acid-induced hepatocyte steatosis. In addition, lycorine promoted WAT browning for thermogenesis and energy consumption, affected the composition of intestinal flora, improved the intestinal barrier, and reduced intestinal inflammation.

Conclusions: EGFR was the target of lycorine intervention in MASLD. Lycorine ameliorated hepatic steatosis, oxidative stress and ferroptosis by affecting the EGFR/PI3K/AKT signaling pathway in MASLD mice. Furthermore, lycorine promoted WAT browning and ameliorated intestinal homeostatic imbalance. The above effects may also have dose-dependent effects.