Molecular and Cellular Biochemistry最新文献

Introduction: Liver fibrosis is a crucial pathological factor in the persistence and progression of chronic liver disease. Increasing evidence has demonstrated the significant potential of extracellular vesicles (EVs) secreted by bone marrow mesenchymal stem cells (BMSCs) in the clinical treatment of liver fibrosis. This study aimed to mechanistically investigate the impact of BMSC-derived EVs (BMSC-EVs) containing miR-7045-5p on the autophagy of activated hepatic stellate cells (HSCs) during liver fibrosis.

Method: BMSCs were isolated from the bilateral femurs and tibiae of mice. Their identity was confirmed via immunofluorescence staining for the BMSC marker CD44. EVs were harvested from BMSC culture medium at passages 3-5 and then DiR-labeled. Labeled BMSC-EVs were co-cultured with the HSC-T6 cell line to determine their uptake and sub-cellular localization in HSCs. Various methods, such as western blotting, qRT-PCR, and ELISA, were employed to assess the effects of BMSC-EVs on the fibrotic activation (marked by COL1-A1 and α-SMA expression) and autophagy (p62, Atg16L1, Beclin-1, and LC3 expression) of HSC-T6 cells. Additionally, the BMSC-EV-induced changes in autophagy-related signaling pathways (PI3K, AKT, and mTOR pathways) in these cells were evaluated. Finally, the gene-chip detection technology was utilized to predict the involvement of BMSC-EV-derived miRNAs (BMSC-EV-miRs) in the observed effects, with a focus on miR-7045-5p, and our findings were validated in HSCs transfected with a miR-7045-5p mimic.

Result: The gene-chip detection results indicated that miR-7045-5p was enriched in BMSC-EVs compared with BMSCs and targeted Akt. In the CCl₄-induced mouse model of liver fibrosis, BMSC-EV-miR-7045-5p ameliorated the fibrosis and enhanced liver function by suppressing the PI3K/Akt/mTOR signaling pathway. Additionally, miR-7045-5p inhibited TGF-β1-induced fibrotic activation of HSC-T6 cells.

Conclusion: BMSC-EVs promote autophagy in HSC-T6 cells and alleviate liver fibrosis by inhibiting the PI3K/Akt/mTOR signaling pathway at least in part by delivering anti-fibrotic miRNAs, such as miR-7045-5p.

T2DM is a serious global health problem and usually caused by unhealthy diet, such diet with high carbohydrate or monosodium glutamate (MSG). In this study, we used the T2DM mice (BALB/c) model by exposing the mice with foods high in carbohydrate (HCD) or MSG (HMD) to determine the changes in molecular expression and methylation pattern of genes correlated to the development of T2DM. The data including clinical data, i.e. body weight, fasting blood glucose, and glucose tolerance, as well as gene expression, methylation pattern of glucose transport related gene (Slc2a4, FTO, and PPARγ) and also collagen deposition were measured. HCD and HMD diet for 18 weeks failed to show any clinical development of T2DM. However, it was shown that both diets significantly altered the methylation pattern and gene expression. A decrease in the expression level of Slc2a4 accompanied with a decreased methylation level in its NF-κB attachment site was observed in both groups. In addition, both treatments also showed a decrease in the expression of PPARγ in contrast to its elevated methylation level. On the other hand, a significant increase in the expression of FTO was apparent. Furthermore, an increase in collagen deposition in both groups was also detected. Overall, this study showed that an alteration on the expression and methylation pattern of the genes that are associated with glucose transportation was observed in HCD and HMD despite having no T2DM clinical development. It can potentially be a new biomarker for detection of pre-diabetes.

Irritable bowel syndrome is a gastrointestinal disorder due to multiple pathologies. While patients with this condition experience anxiety and depressed mood more frequently than healthy individuals, it is unclear how gastrointestinal dysfunction interacts with such neuropsychiatric symptoms. Data suggest that irritable bowel syndrome patients predominantly display a lower zinc intake, which presumably impairs enterochromaffin cells producing 5-hydroxytryptamine, gut bacteria fermenting short-chain fatty acids, and barrier system in the intestine, with the accompanying constipation, diarrhea, low-grade mucosal inflammation, and visceral pain. Dyshomeostasis of copper and zinc concentrations as well as elevated pro-inflammatory cytokine levels in the blood can disrupt blood-cerebrospinal fluid barrier function, leading to locus coeruleus neuroinflammation and hyperactivation with resultant amygdalar overactivation and dorsolateral prefrontal cortex hypoactivation as found in neuropsychiatric disorders. The dysregulation between the dorsolateral prefrontal cortex and amygdala is likely responsible for visceral pain-related anxiety, depressed mood caused by anticipatory anxiety, and visceral pain catastrophizing due to catastrophic thinking or cognitive distortion. Collectively, these events can result in a spiral of gastrointestinal symptoms and neuropsychiatric signs, prompting the progression of irritable bowel syndrome. Given that the negative feedback mechanism in regulation of the hypothalamic-pituitary-adrenal axis is preserved in a subset of neuropsychiatric cases, dorsolateral prefrontal cortex abnormality accompanied by neuropsychiatric symptoms may be a more significant contributing factor in brain-gut axis malfunction than activation of the hypothalamic corticotropin-releasing hormone system. The proposed mechanistic model could predict novel therapeutic interventions for comorbid irritable bowel syndrome and neuropsychiatric disorders.

Autophagy has gained importance in the context of ferroptosis. Nevertheless, a deeper understanding of the regulatory mechanism governing autophagy-dependent ferroptosis is necessary. Cytoglobin (CYGB), a member of the globin family, exhibits antifibrotic effects, regulates cellular reactive oxygen species, and stimulates tumor inhibition. Herein, we present further insights into the role of CYGB in ferroptosis regulation. Our investigation confirmed that CYGB impedes cell proliferation and migration. Furthermore, a significant association between CYGB and the lysosomal pathway was suggested based on the RNA sequencing data analysis. Elevated lysosomal signal and colocalization of CYGB with lysosome-associated membrane glycoprotein 1 (LAMP1) were observed. Moreover, upregulated autophagy and augmented ferroptosis induced by RSL3 were confirmed in CYGB-overexpression cells with an obviously increased colocalization of nuclear receptor coactivator 4 (NCOA4) and LC3B. The autophagy inhibitor bafilomycin or chloroquine alleviated autophagy-dependent degradation of ferritin protein under RSL3 treated condition. Additionally, a colocalization of CYGB with the transferrin receptor (TFR) was confirmed. Our results demonstrate an important functional pathway by which CYGB regulates ferroptosis through TFR-binding and autophagic degradation of ferritin, and provide a potential pathway for the treatment of colorectal cancer.

The pathological signature of Alzheimer's disease (AD) includes the accumulation of toxic protein aggregates, mainly consisting of amyloid beta (Aβ). Recent strides in fundamental research underscore the pivotal role of waste clearance mechanisms in the brain suggesting it may be an early indication of early onset AD. This study delves into the involvement of leptomeningeal cells (LMCs), crucial components forming integral barriers within the clearance system, in the context of AD. We examined the inflammatory cytokine responses of LMCs in the presence of Aβ, alongside assessments of LMC growth response, viability, oxidative stress, and changes in vimentin expression. The LMCs showed no changes in growth, viability, oxidative stress, or vimentin expression in the presence of Aβ, indicating that LMCs are less susceptible to Aβ damage compared to other CNS cells. However, LMCs exhibited a unique pro-inflammatory response to Aβ when compared to an LPS inflammatory control, showing an mRNA expression of pro-inflammatory cytokines such IL-6, IL-10 and IL-33 but no changes in IL-1α and IL-1β. Furthermore, LMCs influenced the astrocyte response to Aβ, as conditioned media from Aβ-treated LMCs was observed to downregulate somatic S100β in astrocytes. We also investigated whether the JAK/STAT3 pathway was involved in the Aβ response of the LMCs, as this pathway has been shown to be activated in astrocytes and neurons in the presence of Aβ. JAK/STAT3 activation was assessed through phosphorylated STAT3, revealing that JAK/STAT3 was not active in the cells when in the presence of Aβ. However, when JAK1 and JAK2 were inhibited, cytokine protein levels of IL7, IL10, IL15 and IL33 levels, which had shown alteration when LMCs were treated with Aβ, returned to base levels. This indicates that although JAK1/STAT3 and JAK2/STAT3 are not the direct pathway for Aβ response in LMCs, JAK1 and JAK2 may still play a role in regulating cytokine levels, potentially through indirect means or crosstalk. Overall, our findings reveal that LMCs are resilient to Aβ toxicity and suggest that JAK1/STAT3 and JAK2/STAT3 does not play a central role in the inflammatory response, providing new insights into the cellular mechanisms underlying AD.

Cardiovascular disease remains the leading cause of global mortality. Current stem cell therapy and heart transplant therapy have limited long-term stability in cardiac function. Cardiac tissue engineering may be one of the key methods for regenerating damaged myocardial tissue. As an ideal scaffold material, hydrogel has become a viable tissue engineering therapy for the heart. Hydrogel can not only provide mechanical support for infarcted myocardium but also serve as a carrier for various drugs, bioactive factors, and cells to increase myocardial contractility and improve the cell microenvironment in the infarcted area, thereby improving cardiac function. This paper reviews the applications of hydrogels and biomedical mechanisms in cardiac tissue engineering and discusses the challenge of clinical transformation of hydrogel in cardiac tissue engineering, providing new strategies for treating cardiovascular diseases.

Stroke, as a neurological disorder with a poor overall prognosis, has long plagued the patients. Current stroke therapy lacks effective treatments. Ferroptosis has emerged as a prominent subject of discourse across various maladies in recent years. As an emerging therapeutic target, notwithstanding its initial identification in tumor cells associated with brain diseases, it has lately been recognized as a pivotal factor in the pathological progression of stroke. Acyl-CoA synthetase long-chain family member 4 (ACSL4) is a potential target and biomarker of catalytic unsaturated fatty acids mediating ferroptosis in stroke. Specifically, the upregulation of ACSL4 leads to heightened accumulation of lipid peroxidation products and reactive oxygen species (ROS), thereby exacerbating the progression of ferroptosis in neuronal cells. ACSL4 is present in various tissues and involved in multiple pathways of ferroptosis. At present, the pharmacological mechanisms of targeting ACSL4 to inhibit ferroptosis have been found in many drugs, but the molecular mechanisms of targeting ACSL4 are still in the exploratory stage. This paper introduces the physiopathological mechanism of ACSL4 and the current status of the research involved in ferroptosis crosstalk and epigenetics, and summarizes the application status of ACSL4 in modern pharmacology research, and discusses the potential application value of ACSL4 in the field of stroke.

Non-small cell lung cancer (NSCLC) stands as the prevailing manifestation of lung cancer, with current therapeutic modalities linked to a dismal prognosis, necessitating further advancements. Hexokinase 2 (HK2), a critical enzyme positioned on the mitochondrial membrane, exerts control over diverse biological pathways, thereby regulating cancer. Nevertheless, the precise role and mechanism of HK2 in NSCLC remain inadequately elucidated, warranting comprehensive investigation. HK2 expression in NSCLC tissues and cell lines was detected through immunohistochemistry and western blot analysis. Concurrently, shRNA assays were applied to scrutinize the impact of HK2 on cell proliferation, apoptosis, migration, and invasion processes in NSCLC cell lines, utilizing CCK8, flow cytometry, wound-healing assay, and transwell techniques. The involvement of HK2 in mitochondrial dynamics was probed through western blot analysis, mitochondrial membrane potential assay, and assessment of ROS generation. Next, the functional role of HK2 was assessed by examining its influence on xenograft tumor growth in nude mice in vivo. Further research has demonstrated that HK2 played a role in NSCLC through its O-GlcNAcylation process. The results of the study revealed that HK2 O-GlcNAcylation promoted the proliferation, migration, and invasive characteristics of NSCLC cells, while alleviating mitochondrial damage, whereas O-GlcNAcylation inactivation yielded the opposite effect. Furthermore, in vivo experiments in nude mice illustrated that HK2 O-GlcNAcylation could stimulate tumor growth in NSCLC. These results suggested that HK2 may impact mitochondrial dynamics in NSCLC through its O-GlcNAcylation, thereby contributing to the progression of NSCLC.

Chemotherapy-induced cardiotoxicity is a major adverse effect, driven by multiple factors in its pathogenesis. Notably, RNAs have emerged as significant contributors in both cancer and heart failure (HF). RNAs carry genetic and metabolic information that mirrors the current state of cells, making them valuable as potential biomarkers and therapeutic tools for diagnosing, predicting, and treating a range of diseases, including cardiotoxicity. Over 97% of the genome is transcribed into non-coding RNAs (ncRNAs), including ribosomal RNA (rRNAs), transfer RNAs (tRNAs), and newly identified microRNAs (miRNAs), circular RNAs (circRNAs), and long non-coding RNAs (lncRNAs). NcRNAs function not only within their originating cells but also in recipient cells by being transported through extracellular compartments, referred to as extracellular RNAs (exRNAs). Since ncRNAs were identified as key regulators of gene expression, numerous studies have highlighted their significance in both cancer and cardiovascular diseases. Nevertheless, the role of ncRNAs in cardiotoxicity remains not fully elucidated. The study aims to review the existing knowledge on ncRNAs in Cardio-Oncology and explore the potential of ncRNA-based biomarkers and therapies. These investigations could advance the clinical application of ncRNA research, improving early detection and mitigating of chemotherapy-induced cardiotoxicity.

The NEK6 (NIMA-related kinase 6) serine/threonine kinase is a pivotal player in a multitude of cellular processes, including the regulation of the cell cycle and the response to DNA damage. Its significance extends to disease pathogenesis, as changes in NEK6 activity have been linked to the development of cancer. Non-synonymous single nucleotide polymorphisms (nsSNPs) in NEK6 have been linked to cancer as they alter the protein's native structure and function. The association between NEK6 activity and cancer development has prompted researchers to explore the effects of genetic variations within the NEK6 gene. Therefore, we utilized advanced computational tools to analyze 155 high-confidence nsSNPs in the NEK6 gene. From this analysis, 21 nsSNPs were identified as potentially harmful, raising concerns about their impact on NEK6 activity and cancer risk. These 21 mutations were then examined for structural alterations, and eight of nsSNPs (I51M, V76A, I134N, Y152D, R171Q, V186G, L237R, and C285S) were found to destabilize the protein. Among the destabilizing mutations screened, a specific mutation, R171Q, stood out due to its conserved nature. To understand its impact on the protein and conformation, all-atom molecular dynamics simulations (MDS) for 100 ns were performed for both Wildtype NEK6 (WT-NEK6) and R171Q. The simulations revealed that the R171Q variant was unstable and led to significant conformational changes in NEK6. This study provides valuable insights into NEK6 dysfunction caused by single amino acid alterations, offering a novel understanding of the molecular mechanisms underlying NEK6-related cancer progression.