Mitochondrial redox impairment and enhanced autophagy in peripheral blood mononuclear cells from type 1 diabetic patients

Egg exosome miR-145-5p decreases mitochondrial ROS to protect chicken embryo hepatocytes against apoptosis through targeting MAPK10

BACKGROUND

Higher embryonic mortality, especially in aged breeding hens, is associated with insufficient hepatic functionality in maintaining redox homeostasis. Our previous study demonstrated that egg exosome-derived miRNAs may play a key role in modulating embryonic oxidation-reduction process, whereas the exact function and mechanism were still poorly understood. The present study aimed to investigate the roles of egg exosome miRNAs in maintaining dynamic equilibrium of free radicals and peroxide agents in embryonic liver, as well as demonstrate the specific mechanism using oxidative stress-challenged hepatocytes.

RESULTS

Compared to 36-week-old breeding hens, decreased hatchability and increased embryonic mortality were observed in 65-week-old breeding hens. Meanwhile, the older group showed the increased MDA levels and decreased SOD and GSH-Px activities in embryonic liver, muscle and serum. Embryonic mortality was significantly positively correlated with MDA level and negatively correlated with GSH-Px activity in embryonic liver. In addition, 363 differentially expressed genes (DEGs) were identified in embryonic liver, 13 differentially expressed miRNAs (DE-miRNAs) were identified in egg exosomes. These DEGs and DE-miRNAs were involved in oxidoreductase activity, glutathione metabolic process, MAPK signaling pathway, apoptosis and autophagy. miRNA-mRNA network analysis further found that DEGs targeted by DE-miRNAs were mainly enriched in programmed cell death, such as apoptosis and autophagy. Wherein, MAPK10 with highest MCC and AUC values was significantly related to GSH-Px activity and MDA level, and served as the target gene of miR-145-5p based on dual luciferase reporter experiment and correlation analysis. Bioinformatics analysis found that miR-145-5p/MAPK10 axis might alleviate peroxide generation and apoptosis. In primary hepatocytes of chick embryos, miR-145-5p transfection significantly reversed H2O2-induced mitochondrial ROS increase, MAPK10, BAX and CASP3 overexpression and excessive apoptosis.

CONCLUSION

Exosome miR-145-5p in eggs could target MAPK10 and decrease mitochondrial ROS, attenuating oxidative damage and apoptosis in hepatocytes of chick embryos. These findings may provide new theoretical basis for the improvement of maternal physiological status to maintain embryonic redox homeostasis by nutritional or genetic modifications.

Poor glycaemic control in type 2 diabetes compromises leukocyte oxygen consumption rate, OXPHOS complex content and neutrophil-endothelial interactions

The mitochondrial electron transport chain becomes overloaded in type 2 diabetes (T2D), which increases ROS (Reactive Oxygen Species) production and impairs mitochondrial function. Peripheral blood mononuclear cells (PBMCs) are critical players in the inflammatory process that underlies T2D. Poor glycaemic control in T2D is closely linked to the development of comorbidities. Our aim was to evaluate if glycaemic control in T2D has an impact on the oxygen consumption rates (OCR) of PBMC, OXPHOS complexes and inflammation. We recruited 181 subjects, consisting of 79 healthy controls, 64 patients with T2D and good glycaemic control (HbA1c<7 %), and 38 T2D patients with poor glycaemic control (HbA1c>7 %). We found a decrease in the basal OCR of PBMCs from patients with HbA1c>7 % with respect to controls (p < 0.05). Maximal OCR and spare respiratory capacity were lower in patients with HbA1c>7 % than in controls and patients with HbA1c<7 % (p < 0.05 for all). Mitochondrial ROS levels were higher in T2D patients, and particularly in the HbA1c > 7 group (p < 0.05 HbA1c<7 % vs control, p < 0.001 HbA1c>7 % vs control; p < 0.001 HbA1c > 7 vs HbA1c < 7). With respect to controls, poor glycaemic control in T2D patients was associated with a decrease in mitochondrial complex III and V (p < 0.05 and p < 0.01, respectively) and enhanced neutrophil-endothelial interactions (p < 0.001 vs controls). MPO levels were enhanced in T2D patients in general (p < 0.05 vs controls), and ICAM-1 and VCAM-1 were specifically increased in HbA1c > 7 patients vs controls (p < 0.01 and p < 0.001, respectively). Negative low-to-moderate correlations were found between HbA1c and basal respiration (r = -0.319, p < 0.05), maximal respiration (r = -0.350, p < 0.01) and spare respiratory capacity (r = -0.295, p < 0.05). Our findings suggest that poor glycaemic control during the progression of T2D compromises mitochondrial respiration and OXPHOS complex content in PBMCs. These alterations occur in parallel to enhanced neutrophil-endothelial interactions and adhesion molecule levels, leaving T2D patients with poor glycaemic control at a higher risk of developing vascular diseases.

Exploring proteomic immunoprofiles: common neurological and immunological pathways in multiple sclerosis and type 1 diabetes mellitus

BACKGROUND

Interest in the study of type 1 diabetes mellitus (T1DM) and multiple sclerosis (MS) has increased because of their significant negative impact on the patient quality of life and the profound implications for the health care system. Although the clinical symptoms of T1DM differ from those of MS, such as pancreatic β-cell failure in T1DM and demyelination in the central nervous system (CNS) in MS, both pathologies are considered as autoimmune-related diseases with shared pathogenic pathways, which include autophagy, inflammation and degeneration, among others. Considering the challenges in obtaining pancreatic β-cells and CNS tissue from patients with T1DM and MS, respectively, it is fundamental to explore alternative methods for evaluating disease status. Proteomic analysis of peripheral blood mononuclear cells (PBMCs) is an ideal approach for identifying novel and potential biomarkers for both autoimmune diseases.

METHODS

We conducted a proteomic analysis of PBMCs from patients with T1DM and relapsing remitting Multiple Sclerosis (herein forth MS) patients (n = 9 per condition), using a label-free quantitative proteomics approach. The patients were diagnosed following the American Diabetes Association (ADA) criteria for T1DM and McDonald criteria for MS respectively, and were aged over 18 years and more than 2 years from the onset respectively.

RESULTS

A total of 2476 proteins were differentially expressed in PBMCs from patients with T1DM and MS patients compared with those form healthy controls (H). Predictive analysis highlighted 15 common proteins, up- or downregulated in PBMCs from patients with T1DM and MS patients vs. healthy controls, involved in the immune system activity (BTF3, TTR, CD59, CSTB), diseases of the neuronal system (TTR), signal transduction (STMN1, LAMTOR5), metabolism of nucleotides (RPS21), proteins (TTR, ENAM, CD59, RPS21, SRP9) and RNA (SRSF10, RPS21). In addition, this study revealed both shared and distinct molecular patterns between the two conditions.

CONCLUSIONS

Compared with H, patients with T1DM and MS presented a specific expression pattern of common proteins has been identified. This pattern underscores the shared mechanisms involved in their immune responses and neurological complications, alongside dysregulation of the autophagy pathway. Notably, CSTB has emerged as a differential biomarker, distinguishing between these two autoimmune diseases.

LncRNA LUCAT1 offers protection against human coronary artery endothelial cellular oxidative stress injury through modulating hsa-miR-6776-5p/LRRC25 axis and activating autophagy flux

BACKGROUND

Coronary artery disease (CAD) has become a dominant economic and health burden worldwide, and the role of autophagy in CAD requires further clarification. In this study, we comprehensively revealed the association between autophagy flux and CAD from multiple hierarchies. We explored autophagy-associated long noncoding RNA (lncRNA) and the mechanisms underlying oxidative stress-induced human coronary artery endothelial cells (HCAECs) injury.

METHODS

(1) Autophagy-related proteins including LC3, p62, Beclin1, ATG5, and ATG7 were immunohistochemical stained in coronary specimens; (2) The levels and function of autophagy in the HCAEC oxidative stress model were evaluated using western blot (WB), transmission electron microscopy (TEM), and mRFP-GFP-LC3 adenovirus transfection experiments; (3) The competing endogenous RNA (ceRNA) network of lncRNA LUCAT1/hsa-miR-6776-5p/LRRC25 axis was constructed and validated; (4) The expression levels of above autophagy-related RNAs in peripheral blood mononuclear cells (PBMCs) were verified by qPCR, and their diagnostic performance was subsequently analyzed using receiver operating characteristic (ROC) analysis.

RESULTS

(1) The expression of LC3, Beclin1, ATG5, and ATG7 demonstrated a consistent decline whereas p62 expression exhibited an opposite increase as atherosclerosis progressed; (2) Autophagy levels was significantly elevated in HCAECs under oxidative stress, while inhibition of the initial stage of autophagy with 3-MA exacerbated cellular damage; (3) The lncRNA LUCAT1/hsa-miR-6776-5p/LRRC25 axis was established through bioinformatic prediction and validated by dual-luciferase reporter assay, which resulted in a significant decrease in autophagy levels in HCAECs; (4) In total, p62, ATG7, lncRNA LUCAT1 and LRRC25 were validated as robust diagnostic biomarkers for CAD.

CONCLUSIONS

Our results delineated the dynamic disruption of the autophagy landscape during the progression of human coronary atherosclerosis and identified the lncRNA LUCAT1/hsa-miR-6776-5p/LRRC25 axis, uncovered through transcriptomic profiling, as a protective mechanism against endothelial cell injury through autophagy activation. Furthermore, we recognized p62, ATG7, lncRNA LUCAT1, and LRRC25 as dependable autophagy-related diagnostic biomarkers in circulating PBMCs, correlating with CAD severity. Collectively, Our findings furnish novel insights into the intricate autophagy landscape at various levels of coronary atherosclerosis and propose potential diagnostic biomarkers, and a theoretical foundation for managing CAD patients.

Tenovin-6 exhibits inhibitory effects on the growth of Sonic Hedgehog (SHH) medulloblastoma, as evidenced by both in vitro and in vivo studies

Medulloblastoma (MB) is the most common malignant brain tumor in children. Within MB, tumors driven by the Sonic Hedgehog (SHH) pathway represent the most heterogeneous subtype, known as SHH subtype medulloblastoma (SHH-MB). Tenovin-6, a recognized p53 activator, has been demonstrated to inhibit autophagy and modulate sirtuin activity, underscoring its potential as a novel therapeutic agent across various malignancies. However, its efficacy in treating SHH-MB remains unexplored. This study aims to investigate the inhibitory effects of tenovin-6 on SHH-MB and elucidate its underlying signaling pathways. We assessed the impact of tenovin-6 on cell proliferation through the CCK-8 and colony formation assays. The scratch and transwell invasion assays were utilized to evaluate the drug's effects on metastasis. Apoptosis and reactive oxygen species (ROS) levels were measured using flow cytometry. Potential signaling pathways were identified via transcriptomics and quantitative PCR (qPCR). Our in vivo studies involved a mouse xenograft model to explore tenovin-6's anticancer efficacy against SHH-MB. The findings indicate that tenovin-6 not only inhibits cell proliferation and metastasis in SHH-MB cell lines but also promotes apoptosis, which is closely linked to its proliferation-inhibiting properties. Additionally, animal experiments confirmed that tenovin-6 suppresses MB growth in vivo. We discovered that tenovin-6 reduces intracellular ROS levels and inhibits autophagy in SHH-MB by disrupting the fusion of autophagosomes with lysosomes, likely through inducing autophagosome formation.

Targeting Autophagy: A Promising Therapeutic Strategy for Diabetes Mellitus and Diabetic Nephropathy

Diabetes mellitus (DM) significantly impairs patients' quality of life, primarily because of its complications, which are the leading cause of mortality among individuals with the disease. Autophagy has emerged as a key process closely associated with DM, including its complications such as diabetic nephropathy (DN). DN is a major complication of DM, contributing significantly to chronic kidney disease and renal failure. The intricate connection between autophagy and DM, including DN, highlights the potential for new therapeutic targets. This review examines the interplay between autophagy and these conditions, aiming to uncover novel approaches to treatment and enhance our understanding of their underlying pathophysiology. It also explores the role of autophagy in maintaining renal homeostasis and its involvement in the development and progression of DM and DN. Furthermore, the review discusses natural compounds that may alleviate these conditions by modulating autophagy.

The Application Potential of the Regulation of Tregs Function by Irisin in the Prevention and Treatment of Immune-Related Diseases

Irisin is a muscle factor induced by exercise, generated through the proteolytic cleavage of the membrane protein fibronectin type III domain-containing protein 5 (FNDC-5). Numerous studies have shown that irisin plays a significant role in regulating glucose and lipid metabolism, inhibiting oxidative stress, reducing systemic inflammatory responses, and providing neuroprotection. Additionally, irisin can exert immunomodulatory functions by regulating regulatory T cells (Tregs). Tregs are a highly differentiated subset of mature T cells that play a key role in maintaining self-immune homeostasis and are closely related to infections, inflammation, immune-related diseases, and tumors. Irisin exerts persistent positive effects on Treg cell functions through various mechanisms, including regulating Treg cell differentiation and proliferation, improving their function, modulating the balance of immune cells, increasing the production of anti-inflammatory cytokines, and enhancing metabolic functions, thereby helping to maintain immune homeostasis and prevent immune-related diseases. As an important myokine, irisin interacts with receptors on the cell membrane, activating multiple intracellular signaling pathways to regulate cell metabolism, proliferation, and function. Although the specific receptor for irisin has not been fully identified, integrins are considered potential receptors. Irisin activates various signaling pathways, including AMPK, MAPK, and PI3K/Akt, through integrin receptors, thereby exerting multiple biological effects. These research findings provide important clues for understanding the mechanisms of irisin's action and theoretical basis for its potential applications in metabolic diseases and immunomodulation. This article reviews the relationship between irisin and Tregs, as well as the research progress of irisin in immune-related diseases such as multiple sclerosis, myasthenia gravis, acquired immune deficiency syndrome, type 1 diabetes, sepsis, and rheumatoid arthritis. Studies have revealed that irisin plays an important role in immune regulation by improving the function of Tregs, suggesting its potential application value in the treatment of immune-related diseases.

Single-cell and transcriptomic analyses reveal the influence of diabetes on ovarian cancer

BACKGROUND

There has been a significant surge in the global prevalence of diabetes mellitus (DM), which increases the susceptibility of individuals to ovarian cancer (OC). However, the relationship between DM and OC remains largely unexplored. The objective of this study is to provide preliminary insights into the shared molecular regulatory mechanisms and potential biomarkers between DM and OC.

METHODS

Multiple datasets from the GEO database were utilized for bioinformatics analysis. Single cell datasets from the GEO database were analysed. Subsequently, immune cell infiltration analysis was performed on mRNA expression data. The intersection of these datasets yielded a set of common genes associated with both OC and DM. Using these overlapping genes and Cytoscape, a protein‒protein interaction (PPI) network was constructed, and 10 core targets were selected. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were then conducted on these core targets. Additionally, advanced bioinformatics analyses were conducted to construct a TF-mRNA-miRNA coregulatory network based on identified core targets. Furthermore, immunohistochemistry staining (IHC) and real-time quantitative PCR (RT-qPCR) were employed for the validation of the expression and biological functions of core proteins, including HSPAA1, HSPA8, SOD1, and transcription factors SREBF2 and GTAT2, in ovarian tumors.

RESULTS

The immune cell infiltration analysis based on mRNA expression data for both DM and OC, as well as analysis using single-cell datasets, reveals significant differences in mononuclear cell levels. By intersecting the single-cell datasets, a total of 119 targets related to mononuclear cells in both OC and DM were identified. PPI network analysis further identified 10 hub genesincludingHSP90AA1, HSPA8, SNRPD2, UBA52, SOD1, RPL13A, RPSA, ITGAM, PPP1CC, and PSMA5, as potential targets of OC and DM. Enrichment analysis indicated that these genes are primarily associated with neutrophil degranulation, GDP-dissociation inhibitor activity, and the IL-17 signaling pathway, suggesting their involvement in the regulation of the tumor microenvironment. Furthermore, the TF-gene and miRNA-gene regulatory networks were validated using NetworkAnalyst. The identified TFs included SREBF2, GATA2, and SRF, while the miRNAs included miR-320a, miR-378a-3p, and miR-26a-5p. Simultaneously, IHC and RT-qPCR reveal differential expression of core targets in ovarian tumors after the onset of diabetes. RT-qPCR further revealed that SREBF2 and GATA2 may influence the expression of core proteins, including HSP90AA1, HSPA8, and SOD1.

CONCLUSION

This study revealed the shared gene interaction network between OC and DM and predicted the TFs and miRNAs associated with core genes in monocytes. Our research findings contribute to identifying potential biological mechanisms underlying the relationship between OC and DM.

Clostridium butyricum and its metabolite butyrate promote ferroptosis susceptibility in pancreatic ductal adenocarcinoma

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive disease with limited therapeutic options. The diversity and composition of the intratumoral microbiota are associated with PDAC outcomes, and modulating the tumor microbiota has the potential to influence tumor growth and the host immune response. Here, we explore whether intervention with butyrate-producing probiotics can limit PDAC progression.

METHODS

Based on the TCGA (PAAD) database, we analyzed the differential communities of intratumoral microbiota in PDAC patients with long survival and short survival and explored the relevant mechanisms of Clostridium butyricum and its metabolite butyrate in the treatment of PDAC. Treatment with Clostridium butyricum or butyrate in combination with the ferroptosis inducer RSL3 in a PDAC mouse model has an inhibitory effect on PDAC progression. The potential molecular mechanisms were verified by flow cytometry, RNA-seq, Western blotting, qRT‒PCR and immunofluorescence.

RESULTS

We found that the tumoral butyrate-producing microbiota was linked to a better prognosis and less aggressive features of PDAC. Intervention with Clostridium butyricum or its metabolite butyrate triggered superoxidative stress and intracellular lipid accumulation, which enhanced ferroptosis susceptibility in PDAC.

CONCLUSION

Our study reveals a novel antitumor mechanism of butyrate and suggests the therapeutic potential of butyrate-producing probiotics in PDAC.

Morphological and molecular changes in the Harderian gland of streptozotocin-induced diabetic rats

Using a rat model of type 1 diabetes (T1D) obtained by treatment with streptozotocin, an antibiotic that destroys pancreatic β-cells, we evaluated the influence of subsequent hyperglycemia on the morphology and physiology of the Harderian gland (HG). HG is located in the medial corner of the orbit of many terrestrial vertebrates and, in rodents, is characterized by the presence of porphyrins, which being involved in the phototransduction, through photo-oxidation, produce reactive oxygen species activating the autophagy pathway. The study focused on the expression of some morphological markers involved in cell junction formation (occludin, connexin-43, and α-tubulin) and mast cell number (MCN), as well as autophagic and apoptotic pathways. The expression of enzymes involved in steroidogenesis [steroidogenic acute regulatory protein (StAR), and 3β-hydroxysteroid dehydrogenase (3β-HSD)] and the level of lipid peroxidation by thiobarbituric acid reactive species assay were also evaluated. The results strongly indicate, for the first time, that T1D has a negative impact on the pathophysiology of rat HG, as evidenced by increased oxidative stress, morphological and biochemical alterations, hyperproduction and secretion of porphyrins, increased MCN, reduced protein levels of StAR and 3β-HSD, and, finally, induced autophagy and apoptosis. All the combined data support the use of the rat HG as a suitable experimental model to elucidate the molecular damage/survival pathways elicited by stress conditions.

Exploring the protective effects of herbal monomers against diabetic retinopathy based on the regulation of autophagy and apoptosis: A review

Diabetic retinopathy (DR) has become one of the top 3 blinding eye diseases in the world. In spite of recent therapeutic breakthroughs, it is not yet possible to cure DR through pharmacotherapy. Cell death is thought to play a key role in the pathogenesis of DR. Moderate modulation of cellular autophagy and inhibition of apoptosis have been identified as effective targets for the treatment of DR. Numerous phytochemicals have emerged as potential new drugs for the treatment of DR. We collected basic DR research on herbal monomers through keywords such as autophagy and apoptosis, and conducted a systematic search for relevant research articles published in the PubMed database. This review provides the effects and reports of herbal monomers on various DR cellular and animal models in vivo and in vitro in the available literature, and emphasizes the importance of cellular autophagy and apoptosis as current DR therapeutic targets. Based on our review, we believe that herbal monomers that modulate autophagy and inhibit apoptosis may be potentially effective candidates for the development of new drugs in the treatment of DR. It provides a strategy for further development and application of herbal medicines for DR treatment.