Tetrahedral Framework Nucleic Acids Ameliorate Insulin Resistance in Type 2 Diabetes Mellitus via the PI3K/Akt Pathway

Flavonoid Derivatives Isolated from Hypericum monogynum Ameliorate Insulin Resistance via Modulation of IRS-1/PI3K/Akt/FOXO1 Pathway in HepG2 Cells

In this study, two high-content flavonoid derivatives [3-8 biapigenin (HM 104) and quercetin-3-O-β-d-galactopyranoside (HM 111)] were obtained through the bioactivity-guided isolation of antidiabetic compounds from Hypericum monogynum flowers. HM 104 and HM 111 exhibited good glucose consumption in fatty acid-induced insulin-resistant HepG2 cells. Moreover, both active compounds enhanced glucose uptake by restoring the expression of key regulators of glucose metabolism, including insulin receptor substrate 1, phosphoinositide 3-kinase, protein kinase B, and glucose transporter type 4, and by mitigating the expression of forkhead box O1 and the factors involved in gluconeogenesis. They upregulate the phosphorylation of glycogen synthase kinase-3β, which may affect glycogen synthesis. Furthermore, the production of reactive oxygen species was decreased by the two compounds. This study provides novel mechanistic insights into the protective effects of flavonoid derivatives isolated from H. monogynum flowers in preventing and managing insulin resistance and associated metabolic disorders.

Exploring Framework Nucleic Acids: A Perspective on Their Cellular Applications

Cells are fundamental units of life. The coordination of cellular functions and behaviors relies on a cascade of molecular networks. Technologies that enable exploration and manipulation of specific molecular events in living cells with high spatiotemporal precision would be critical for pathological study, disease diagnosis, and treatment. Framework nucleic acids (FNAs) represent a novel class of nucleic acid materials characterized by their monodisperse and rigid nanostructure. Leveraging their exceptional programmability, convenient modification property, and predictable atomic-level architecture, FNAs have attracted significant attention in diverse cellular applications such as cell recognition, imaging, manipulation, and therapeutic interventions. In this perspective, we will discuss the utilization of FNAs in living cell systems while critically assessing the opportunities and challenges presented in this burgeoning field.

VEGFB ameliorates insulin resistance in NAFLD via the PI3K/AKT signal pathway

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is one of the most universal liver diseases with complicated pathogenesis throughout the world. Insulin resistance is a leading risk factor that contributes to the development of NAFLD. Vascular endothelial growth factor B (VEGFB) was described by researchers as contributing to regulating lipid metabolic disorders. Here, we investigated VEGFB as a main target to regulate insulin resistance and metabolic syndrome.

METHODS

In this study, bioinformatics, transcriptomics, morphological experiments, and molecular biology were used to explore the role of VEGFB in regulating insulin resistance in NAFLD and its molecular mechanism based on human samples, animal models, and cell models. RNA-seq was performed to analyze the signal pathways associated with VEGFB and NAFLD; Palmitic acid and High-fat diet were used to induce insulin-resistant HepG2 cells model and NAFLD animal model. Intracellular glucolipid contents, glucose uptake, hepatic and serum glucose and lipid levels were examined by Microassay and Elisa. Hematoxylin-eosin staining, Oil Red O staining, and Periodic acid-schiff staining were used to analyze the hepatic steatosis, lipid droplet, and glycogen content in the liver. Western blot and quantitative real-time fluorescent PCR were used to verify the expression levels of the VEGFB and insulin resistance-related signals PI3K/AKT pathway.

RESULTS

We observed that VEGFB is genetically associated with NAFLD and the PI3K/AKT signal pathway. After VEGFB knockout, glucolipids levels were increased, and glucose uptake ability was decreased in insulin-resistant HepG2 cells. Meanwhile, body weight, blood glucose, blood lipids, and hepatic glucose of NAFLD mice were increased, and hepatic glycogen, glucose tolerance, and insulin sensitivity were decreased. Moreover, VEGFB overexpression reduced glucolipids and insulin resistance levels in HepG2 cells. Specifically, VEGFB/VEGFR1 activates the PI3K/AKT signals by activating p-IRS1Ser307 expression, inhibiting p-FOXO1pS256 and p-GSK3Ser9 expressions to reduce gluconeogenesis and glycogen synthesis in the liver. Moreover, VEGFB could also enhance the expression level of GLUT2 to accelerate glucose transport and reduce blood glucose levels, maintaining glucose homeostasis.

CONCLUSIONS

Our studies suggest that VEGFB could present a novel strategy for treating NAFLD as a positive factor.

Framework Nucleic Acids Loaded with Quercetin: Protecting Retinal Neurovascular Unit via the Protein Kinase B/Heme Oxygenase-1 Pathway

Retinal neovascular disease is a leading cause of vision loss and blindness globally. It occurs when abnormal new blood vessels form in the retina. In this study, we utilized tetrahedral framework nucleic acids (tFNAs) as vehicles to load quercetin (QUE), a small-molecule flavonoid, forming a deoxyribonucleic acid (DNA) nanocomplex, tFNAs-QUE. Our data show this nanocomplex inhibits pathological neovascularization, reduces the area of retinal nonperfusion area, protects retinal neurons, and preserves the visual function. Further, we discovered that tFNAs-QUE selectively upregulates the AKT/Nrf2/HO-1 signaling pathway, which can suppress pathological vascular growth and exert antioxidative effects. Therefore, this study presents a promising small-molecule-loading mechanism for the treatment of ischemic retinal diseases.

Valorization of cell wall polysaccharides extracted from Liubao brick tea residues: chemical, structural, and hypoglycemic properties

BACKGROUND

Tea dregs, typically generated during the production of instant tea or tea beverages, have conventionally been regarded as waste material and routinely discarded. Nevertheless, contemporary research endeavors are concentrating on discovering efficient methods for utilizing the potential of this discarded resource.

RESULTS

In this study, we employed a sequential extraction method using chemical chelating agents to extract and isolate four distinct cell wall polysaccharides, designated as CWTPS-1 through CWTPS-4, from the tea dregs of Liubao brick tea. A comprehensive investigation into their physicochemical, structural, and hypoglycemic properties was conducted. The analysis of chemical composition and physicochemical characteristics revealed that all four CWTPSs were characterized as acidic polysaccharides, albeit with varying chemical compositions and physicochemical attributes. Specifically, the xyloglucan fractions, CWTPS-3 and CWTPS-4, were found to be rich in glucose and xylose, displaying a more uniform molecular weight distribution, greater structural stability, and a more irregular surface compared to the others. Moreover, they exhibited a higher diversity of monosaccharide residues. Importantly, our research unveiled that all four CWTPSs exhibited the capacity to modulate key glucose-regulated and antioxidant enzyme activities within HepG2 cells via the IRS-1-PI3K/AKT signaling pathway, thereby ameliorating cellular insulin resistance. Furthermore, our correlation analysis highlighted significant associations between monosaccharide composition and neutral sugar content with the observed hypoglycemic activity of CWTPSs.

CONCLUSION

This study highlights the potential of utilizing tea dregs as a valuable resource, making a significant contribution to the advancement of the tea industry. Furthermore, CWTPS-4 exhibits promising prospects for further development as a functional food ingredient or additive. © 2024 Society of Chemical Industry.

Unveiling the bioinformatic genes and their involved regulatory mechanisms in type 2 diabetes combined with osteoarthritis

Background

Type 2 Diabetes Mellitus (T2D) and Osteoarthritis (OA) are both prevalent diseases that significantly impact the health of patients. Increasing evidence suggests that there is a big correlation between T2D and OA, but the molecular mechanisms remain elusive. The aims of this study are to investigate the shared biomarkers and potential molecular mechanisms in T2D combined with OA.

Methods

T2D and OA-related differentially expressed genes (DEGs) were identified via bioinformatic analysis on Gene Expression Omnibus (GEO) datasets GSE26168 and GSE114007 respectively. Subsequently, extensive target prediction and network analysis were finished with Gene Ontology (GO), protein-protein interaction (PPI), and pathway enrichment with DEGs. The transcription factors (TFs) and miRNAs coupled in co-expressed DEGs involved in T2D and OA were predicted as well. The key genes expressed both in the clinical tissues of T2D and OA were detected with western blot and qRT-PCR assay. Finally, the most promising candidate compounds were predicted with the Drug-Gene Interaction Database (DGIdb) and molecular docking.

Results

In this study, 209 shared DEGs between T2D and OA were identified. Functional analysis disclosed that these DEGs are predominantly related to ossification, regulation of leukocyte migration, extracellular matrix (ECM) structural constituents, PI3K/AKT, and Wnt signaling pathways. Further analysis via Protein-Protein Interaction (PPI) analysis and validation with external datasets emphasized MMP9 and ANGPTL4 as crucial genes in both T2D and OA. Our findings were validated through qRT-PCR and Western blot analyses, which indicated high expression levels of these pivotal genes in T2D, OA, and T2D combined with OA cases. Additionally, the analysis of Transcription Factors (TFs)-miRNA interactions identified 7 TFs and one miRNA that jointly regulate these important genes. The Receiver Operating characteristic (ROC) analysis demonstrated the significant diagnostic potential of MMP9 and ANGPTL4.Moreover, we identified raloxifene, ezetimibe, and S-3304 as promising agents for patients with both T2D and OA.

Conclusion

This study uncovers the shared signaling pathways, biomarkers, potential therapeutics, and diagnostic models for individuals suffering from both T2D and OA. These findings not only present novel perspectives on the complex interplay between T2D and OA but also hold significant promise for improving the clinical management and prognosis of patients with this concurrent condition.

Biomaterials Designed to Modulate Reactive Oxygen Species for Enhanced Bone Regeneration in Diabetic Conditions

Diabetes mellitus, characterized by enduring hyperglycemia, precipitates oxidative stress, engendering a spectrum of complications, notably increased bone vulnerability. The genesis of reactive oxygen species (ROS), a byproduct of oxygen metabolism, instigates oxidative detriment and impairs bone metabolism in diabetic conditions. This review delves into the mechanisms of ROS generation and its impact on bone homeostasis within the context of diabetes. Furthermore, the review summarizes the cutting-edge progress in the development of ROS-neutralizing biomaterials tailored for the amelioration of diabetic osteopathy. These biomaterials are engineered to modulate ROS dynamics, thereby mitigating inflammatory responses and facilitating bone repair. Additionally, the challenges and therapeutic prospects of ROS-targeted biomaterials in clinical application of diabetic bone disease treatment is addressed.

Waist circumference glucose, a novel and effective predictor of type 2 diabetes: a prospective cohort study

Introduction

Waist circumference (WC) and fasting plasma glucose (FPG) have been demonstrated as risk factors for type 2 diabetes mellitus (T2DM). Evidence is limited regarding the association of the combination of WC and FPG (WyG) with the risk of T2DM. The primary aim of the study was to investigate the relationship between WyG and T2DM.

Research design and methods

The current study was a population-based cohort study using data from the NAGALA database. Participants were divided into tertiles based on WyG. Cox proportional hazard regression model was applied to identify the association of WyG with T2DM.

Results

During a median follow-up of 6.19 years in the normoglycemia group and 5.58 years in the prediabetes group, respectively, 88 and 285 individuals in the two groups received a diagnosis of T2DM. After full adjustment, risk of T2DM increased in step-wise fashion with increasing tertiles of WyG. For a per-SD increase in WyG, the hazard ratios for T2DM were 3.05 (95% CI 2.64 - 3.51) in all populations, 1.94 (95% CI 1.46 - 2.58) in the normoglycemia group and 1.63 (95% CI 1.40 - 1.90) in the prediabetes group. The interaction between WyG and fatty liver on T2DM was statistically significant in the prediabetes group (P for interaction = 0.034).

Conclusions

Elevated WyG was independently associated with incident T2DM in Japan. Baseline WyG help identify individuals at high risk of T2DM and implement effective preventive measures.

Activation of NRF2 by epiberberine improves oxidative stress and insulin resistance in T2DM mice and IR-HepG2 cells in an AMPK dependent manner

ETHNOPHARMACOLOGICAL RELEVANCE

Phytochemical compounds offer a distinctive edge in diabetes management, attributed to their multifaceted target mechanisms and minimal toxicological profiles. Epiberberine (EPI), an alkaloid derived from plants of the Rhizoma Coptidis, has been reported to have antidiabetic effects. However, the underlying molecular mechanism of EPI are not fully elucidated.

AIM OF THE STUDY

This study explored the anti-diabetic effects of EPI and the role of the NRF2/AMPK signaling pathway in improving insulin resistance.

MATERIALS AND METHODS

We utilized two distinct models: in vivo, we employed mice with type 2 diabetes mellitus (T2DM) induced by high-fat diet (HFD) and streptozotocin (STZ) to conduct a range of assessments including measuring physical parameters, conducting biochemical analyses, examining histopathology, and performing Western blot tests. In parallel, in vitro experiments were carried out using insulin resistance (IR)-HepG2 cells, through which we conducted a CCK8 assay, glucose uptake tests, Western blot analyses, and flow cytometry studies.

RESULTS

In the EPI-treated group of T2DM mice, there was a significant reduction in hyperglycemia, IR, and hyperlipidemia, accompanied by beneficial changes in the liver and pancreas, as well as enhanced glucose uptake in IR-HepG2 cells. Herein, our finding also provided evidence that EPI could increase the expression of GLUT4 and activated the IRS-1/PI3K/AKT insulin signaling pathway to improve IR in vitro and in vivo. Moreover, EPI alleviated oxidative stress by enhancing SOD and GPX-px activity, decreasing reactive oxygen species (ROS) and malondialdehyde (MDA) content, and promoting nuclear factor (erythroid-derived 2)-like 2 (NRF2), total NRF2, NAD(P)H-quinone oxidoreductase (NQO1) and heme oxygenase-1 (HO-1) expression in the liver tissue of T2DM mice and IR-HepG2 cells. Furthermore, EPI decreased oxidative stress and improved IR, but these benefits were nullified by siNRF2 transfection. In particular, AMP-activated protein kinase (AMPK) deficiency by short-hairpin RNA (shRNA) partially reversed the effects of EPI on nuclear transcription, oxidative stress, and IR of NRF2 in IR-HepG2 cells.

CONCLUSIONS

Taken together, EPI activated NRF2-dependent AMPK cascade to protect T2DM from oxidative stress, thereby alleviating IR.

Recent advances in molecular mechanisms of skin wound healing and its treatments

The skin, being a multifaceted organ, performs a pivotal function in the complicated wound-healing procedure, which encompasses the triggering of several cellular entities and signaling cascades. Aberrations in the typical healing process of wounds may result in atypical scar development and the establishment of a persistent condition, rendering patients more vulnerable to infections. Chronic burns and wounds have a detrimental effect on the overall quality of life of patients, resulting in higher levels of physical discomfort and socio-economic complexities. The occurrence and frequency of prolonged wounds are on the rise as a result of aging people, hence contributing to escalated expenditures within the healthcare system. The clinical evaluation and treatment of chronic wounds continue to pose challenges despite the advancement of different therapeutic approaches. This is mainly owing to the prolonged treatment duration and intricate processes involved in wound healing. Many conventional methods, such as the administration of growth factors, the use of wound dressings, and the application of skin grafts, are used to ease the process of wound healing across diverse wound types. Nevertheless, these therapeutic approaches may only be practical for some wounds, highlighting the need to advance alternative treatment modalities. Novel wound care technologies, such as nanotherapeutics, stem cell treatment, and 3D bioprinting, aim to improve therapeutic efficacy, prioritize skin regeneration, and minimize adverse effects. This review provides an updated overview of recent advancements in chronic wound healing and therapeutic management using innovative approaches.

Exploring the mechanism of Jinlida granules against type 2 diabetes mellitus by an integrative pharmacology strategy

Jinlida granule (JLD) is a Traditional Chinese Medicine (TCM) formula used for the treatment of type 2 diabetes mellitus (T2DM). However, the mechanism of JLD treatment for T2DM is not fully revealed. In this study, we explored the mechanism of JLD against T2DM by an integrative pharmacology strategy. Active components and corresponding targets were retrieved from Traditional Chinese Medicine System Pharmacology (TCMSP), SwissADME and Bioinformatics Analysis Tool for Molecular Mechanisms of Traditional Chinese Medicine Database (BATMAN-TCM) database. T2DM-related targets were obtained from Drugbank and Genecards databases. The protein-protein interaction (PPI) network was constructed and analyzed with STRING (Search Toll for the Retrieval of Interacting Genes/proteins) and Cytoscape to get the key targets. Then, Gene Ontology (GO) and Kyoto Encyclopedia of Gene and Genomes (KEGG) enrichment analyses were performed with the Database for Annotation, Visualization and Integrated Discovery (DAVID). Lastly, the binding capacities and reliability between potential active components and the targets were verified with molecular docking and molecular dynamics simulation. In total, 185 active components and 337 targets of JLD were obtained. 317 targets overlapped with T2DM-related targets. RAC-alpha serine/threonine-protein kinase (AKT1), tumor necrosis factor (TNF), interleukin-6 (IL-6), cellular tumor antigen p53 (TP53), prostaglandin G/H synthase 2 (PTGS2), Caspase-3 (CASP3) and signal transducer and activator of transcription 3 (STAT3) were identified as seven key targets by the topological analysis of the PPI network. GO and KEGG enrichment analyses showed that the effects were primarily associated with gene expression, signal transduction, apoptosis and inflammation. The pathways were mainly enriched in PI3K-AKT signaling pathway and AGE-RAGE signaling pathway in diabetic complications. Molecular docking and molecular dynamics simulation verified the good binding affinity between the key components and targets. The predicted results may provide a theoretical basis for drug screening of JLD and a new insight for the therapeutic effect of JLD on T2DM.

Framework nucleic acids as promising reactive oxygen species scavengers for anti-inflammatory therapy

Reactive oxygen species (ROS) are an array of derivatives of molecular oxygen that participate in multiple physiological processes under the control of redox homeostasis. However, under pathological conditions, the over-production of ROS often leads to oxidative stress and inflammatory reactions, indicating a potential therapeutic target. With the rapid development of nucleic acid nanotechnology, scientists have exploited various DNA nanostructures with remarkable biocompatibility, programmability, and structural stability. Among these novel organic nanomaterials, a group of skeleton-like framework nucleic acid (FNA) nanostructures attracts the most interest due to their outstanding self-assembly, cellular endocytosis, addressability, and functionality. Surprisingly, different FNAs manifest similarly satisfactory antioxidative and anti-inflammatory effects during their biomedical application process. First, they are intrinsically endowed with the ability to neutralize ROS due to their DNA nature. Therefore, they are extensively involved in the complicated inflammatory signaling network. Moreover, the outstanding editability of FNAs also allows for flexible modifications with nucleic acids, aptamers, peptides, antibodies, low-molecular-weight drugs, and so on, thus further strengthening the targeting and therapeutic ability. This review focuses on the ROS-scavenging potential of three representative FNAs, including tetrahedral framework nucleic acids (tFNAs), DNA origami, and DNA hydrogels, to summarize the recent advances in their anti-inflammatory therapy applications. Although FNAs exhibit great potential in treating inflammatory diseases as promising ROS scavengers, massive efforts still need to be made to overcome the emerging challenges in their clinical translation.

A DNA tetrahedron-based ferroptosis-suppressing nanoparticle: superior delivery of curcumin and alleviation of diabetic osteoporosis

Diabetic osteoporosis (DOP) is a significant complication that poses continuous threat to the bone health of patients with diabetes; however, currently, there are no effective treatment strategies. In patients with diabetes, the increased levels of ferroptosis affect the osteogenic commitment and differentiation of bone mesenchymal stem cells (BMSCs), leading to significant skeletal changes. To address this issue, we aimed to target ferroptosis and propose a novel therapeutic approach for the treatment of DOP. We synthesized ferroptosis-suppressing nanoparticles, which could deliver curcumin, a natural compound, to the bone marrow using tetrahedral framework nucleic acid (tFNA). This delivery system demonstrated excellent curcumin bioavailability and stability, as well as synergistic properties with tFNA. Both in vitro and in vivo experiments revealed that nanoparticles could enhance mitochondrial function by activating the nuclear factor E2-related factor 2 (NRF2)/glutathione peroxidase 4 (GPX4) pathway, inhibiting ferroptosis, promoting the osteogenic differentiation of BMSCs in the diabetic microenvironment, reducing trabecular loss, and increasing bone formation. These findings suggest that curcumin-containing DNA tetrahedron-based ferroptosis-suppressing nanoparticles have a promising potential for the treatment of DOP and other ferroptosis-related diseases.

The combination of body mass index and fasting plasma glucose is associated with type 2 diabetes mellitus in Japan: a secondary retrospective analysis

Background

Body mass index (BMI) and fasting plasma glucose (FPG) are known risk factors for type 2 diabetes mellitus (T2DM), but data on the prospective association of the combination of BMI and FPG with T2DM are limited. This study sought to characterize the association of the combination of BMI and FPG (ByG) with T2DM.

Methods

The current study used the NAGALA database. We categorized participants by tertiles of ByG. The association of ByG with T2DM was expressed with hazard ratios (HRs) with 95% confidence intervals (CIs) after adjustment for potential risk factors.

Results

During a median follow-up of 6.19 years in the normoglycemia cohort and 5.58 years in the prediabetes cohort, the incidence of T2DM was 0.75% and 7.79%, respectively. Following multivariable adjustments, there were stepwise increases in T2DM with increasing tertiles of ByG. After a similar multivariable adjustment, the risk of T2DM was 2.57 (95% CI 2.26 - 2.92), 1.97 (95% CI 1.53 - 2.54) and 1.50 (95% CI 1.30 - 1.74) for a per-SD change in ByG in all populations, the normoglycemia cohort and the prediabetes cohort, respectively.

Conclusion

ByG was associated with an increased risk of T2DM in Japan. The result reinforced the importance of the combination of BMI and FPG in assessing T2DM risk.

LIPUS-SCs-Exo promotes peripheral nerve regeneration in cavernous nerve crush injury-induced ED rats via PI3K/Akt/FoxO signaling pathway

OBJECTIVE

Clinical treatment of erectile dysfunction (ED) caused by cavernous nerve (CN) injury during pelvic surgery is difficult. Low-intensity pulsed ultrasound (LIPUS) can be a potential strategy for neurogenic ED (NED). However, whether Schwann cells (SCs) can respond to LIPUS stimulation signals is unclear. This study aims to elucidate the signal transmission between SCs paracrine exosome (Exo) and neurons stimulated by LIPUS, as well as to analyze the role and potential mechanisms of exosomes in CN repair after injury.

METHODS

The major pelvic ganglion (MPG) neurons and MPG/CN explants were stimulated with LIPUS of different energy intensities to explore the appropriate LIPUS energy intensity. The exosomes were isolated and purified from LIPUS-stimulated SCs (LIPUS-SCs-Exo) and non-stimulated SCs (SCs-Exo). The effects of LIPUS-SCs-Exo on neurite outgrowth, erectile function, and cavernous penis histology were identified in bilateral cavernous nerve crush injury (BCNI)-induced ED rats.

RESULTS

LIPUS-SCs-Exo group can enhance the axon elongation of MPG/CN and MPG neurons compared to SCs-Exo group in vitro. Then, the LIPUS-SCs-Exo group showed a stronger ability to promote the injured CN regeneration and SCs proliferation compared to the SCs-Exo group in vivo. Furthermore, the LIPUS-SCs-Exo group increased the Max intracavernous pressure (ICP)/mean arterial pressure (MAP), lumen to parenchyma and smooth muscle to collagen ratios compared to the SCs-Exo group in vivo. Additionally, high-throughput sequencing combined with bioinformatics analysis revealed the differential expression of 1689 miRNAs between the SCs-Exo group and the LIPUS-SCs-Exo group. After LIPUS-SCs-Exo treatment, the phosphorylated levels of Phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt) and forkhead box O (FoxO) in MPG neurons increased significantly compared to negative control (NC) and SCs-Exo groups.

CONCLUSION

Our study revealed that LIPUS stimulation could regulate the gene of MPG neurons by changing miRNAs derived from SCs-Exo, then activating the PI3K-Akt-FoxO signal pathway to enhance nerve regeneration and restore erectile function. This study had important theoretical and practical significance for improving the NED treatment.

Functional nucleic acids for the treatment of diabetic complications

In recent decades, diabetes mellitus (DM) has become a major global health problem owing to its high prevalence and increased incidence of diabetes-associated complications, including diabetic wounds (DWs), diabetic nephropathy, metabolic syndrome, diabetic retinopathy, and diabetic neuropathy. In both type 1 and type 2 diabetes, tissue damage is organ-specific, but closely related to the overproduction of reactive oxygen species (ROS) and hyperglycaemia-induced macrovascular system damage. However, existing therapies have limited effects on complete healing of diabetic complications. Fortunately, recent advances in functional nucleic acid materials have provided new opportunities for the treatment and diagnosis of diabetic complications. Functional nucleic acids possess independent structural functions that can replace traditional proteases and antibodies and perform specific biological non-genetic functions. This review summarises the current functional nucleic acid materials reported for the treatment of diabetic complications, including tetrahedral framework nucleic acids (tFNAs), short interfering RNA (siRNA), micorRNA (miRNA), locked nucleic acids, antisense oligonucleotides (ASOs), and DNA origami, which may assist in the development of novel nucleic acids with new functions and capabilities for better healing of diabetic complications.

Natural exosomes-like nanoparticles in mung bean sprouts possesses anti-diabetic effects via activation of PI3K/Akt/GLUT4/GSK-3β signaling pathway

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease characterized by hyperglycemia and insulin resistance. Mung bean sprouts are traditionally considered a "folk" hypoglycemic food and their pharmacological effects and underlying mechanisms warrant further investigation.

PURPOSE

This study aimed to investigate the anti-diabetic effects of the exosomes-like nanoparticles in mung bean sprouts (MELNs) and explore the related molecular mechanisms.

RESULTS

MELNs were isolated using a differential centrifugation-polyethylene glycol (PEG) method, and the identification of MELNs were confirmed by PAGE gel electrophoresis, agarose gel electrophoresis, thin-layer chromatography (TLC), and transmission electron microscopy (TEM). In the high-fat diet/streptozotocin (HFD/STZ) mouse model, MELNs ameliorated the progression of T2DM by increasing oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) results, decreasing the fasting blood glucose level, and reducing the serum triglycerides (TG) and total cholesterol (TC). Histopathological examinations indicated MELNs diminished inflammatory infiltration of hepatocytes and amplified the area of islet B cells. In addition, MELNs decreased the oxidative stress levels in liver tissue and had good biocompatibility. In vitro experiments verified that MELNs improved the viability of glucosamine (GlcN) induced insulin-resistant hepatocytes. Furthermore, this study also revealed that MELNs upregulated GLUT4 & Nrf2 and down-regulated GSK-3β via activating the PI3K/Akt signaling pathway, promoting the production of antioxidant enzymes, such as HO-1 and SOD, to reduce oxidative stress.

CONCLUSION

MELNs mitigated the progression of type 2 diabetes in HFD/STZ mouse model. The underlying molecular mechanism is related to PI3K/Akt/GLUT4/GSK-3β signaling pathway.

Chinese Sumac Fruits (Rhus chinesis Mill.) Alleviate Type 2 Diabetes in C57BL/6 Mice through Repairing Islet Cell Functions, Regulating IRS-1/PI3K/AKT Pathways and Promoting the Entry of Nrf2 into the Nucleus

This research aimed to probe the potential alleviative effects of ethanol extracts of Chinese sumac (Rhus chinesis Mill.) fruits against type 2 diabetes mellitus (T2DM) in C57BL/6 mice induced by high-fat/high-fructose diet (HFFD) and streptozotocin. The results showed that the ethanol extracts could significantly regulate blood glucose levels, glycosylated hemoglobin, blood lipids, insulin, and insulin resistance, while also restoring endogenous oxidative stress. Pathological and immunohistochemical analyses revealed that the extracts partially restored the physiological function of islet cells. Furthermore, Western blotting results suggested that the extracts could regulate the protein expression in IRS-1/PI3K/AKT signaling pathway, and immunofluorescence findings demonstrated their potential to promote the translocation of Nrf2 into the nucleus. This study elucidated a novel finding that ethanol extracts derived from Chinese sumac fruits have the potential to alleviate symptoms of T2DM in mice. Moreover, these findings could offer valuable scientific insights into the potential utilization of R. chinensis fruits as nutritional supplement and/or functional food to prevent or ameliorate diabetes.

Tetrahedral framework nucleic acids enhance the chondrogenic potential of human umbilical cord mesenchymal stem cells via the PI3K/AKT axis

The field of regenerative medicine faces a notable challenge in terms of the regeneration of articular cartilage. Without proper treatment, it can lead to osteoarthritis. Based on the research findings, human umbilical cord mesenchymal stem cells (hUMSCs) are considered an excellent choice for regenerating cartilage. However, there is still a lack of suitable biomaterials to control their ability to self-renew and differentiate. To address this issue, in this study using tetrahedral framework nucleic acids (tFNAs) as a new method in an in vitro culture setting to manage the behaviour of hUMSCs was proposed. Then, the influence of tFNAs on hUMSC proliferation, migration and chondrogenic differentiation was explored by combining bioinformatics methods. In addition, a variety of molecular biology techniques have been used to investigate deep molecular mechanisms. Relevant results demonstrated that tFNAs can affect the transcriptome and multiple signalling pathways of hUMSCs, among which the PI3K/Akt pathway is significantly activated. Furthermore, tFNAs can regulate the expression levels of multiple proteins (GSK3β, RhoA and mTOR) downstream of the PI3K-Akt axis to further enhance cell proliferation, migration and hUMSC chondrogenic differentiation. tFNAs provide new insight into enhancing the chondrogenic potential of hUMSCs, which exhibits promising potential for future utilization within the domains of AC regeneration and clinical treatment.

Recent progress and application of the tetrahedral framework nucleic acid materials on drug delivery

INTRODUCTION

The application of DNA framework nucleic acid materials in the biomedical field has witnessed continual expansion. Among them, tetrahedral framework nucleic acids (tFNAs) have gained significant traction as the foremost biological vectors due to their superior attributes of editability, low immunogenicity, biocompatibility, and biodegradability. tFNAs have demonstrated promising results in numerous in vitro and in vivo applications.

AREAS COVERED

This review summarizes the latest research on tFNAs in drug delivery, including a discussion of the advantages of tFNAs in regulating biological behaviors, and highlights the updated development and advantageous applications of tFNAs-based nanostructures from static design to dynamically responsive design.

EXPERT OPINION

tFNAs possess distinct biological regulatory attributes and can be taken up by cells without the requirement of transfection, differentiating them from other biological vectors. tFNAs can be easily physically/chemically modified and seamlessly incorporated with other functional systems. The static design of the tFNAs-based drug delivery system makes it versatile, reproducible, and predictable. Further use of the dynamic response mechanism of DNA to external stimuli makes tFNAs-based drug delivery more effective and specific, improving the uptake and utilization of the payload by the intended target. Dynamic targeting is poised to become the future primary approach for drug delivery.

Tetrahedral framework nucleic acids inhibit pathological neovascularization and vaso-obliteration in ischaemic retinopathy via PI3K/AKT/mTOR signalling pathway

This study aimed to explore the effect and the molecular mechanism of tetrahedral framework nucleic acids (tFNAs), a novel self-assembled nanomaterial with excellent biocompatibility and superior endocytosis ability, in inhibition of pathological retinal neovascularization (RNV) and more importantly, in amelioration of vaso-obliteration (VO) in ischaemic retinopathy. tFNAs were synthesized from four single-stranded DNAs (ssDNAs). Cell proliferation, wound healing and tube formation assays were performed to explore cellular angiogenic functions in vitro. The effects of tFNAs on reducing angiogenesis and inhibiting VO were explored by oxygen-induced retinopathy (OIR) model in vivo. In vitro, tFNAs were capable to enter endothelial cells (ECs), inhibit cell proliferation, tube formation and migration under hypoxic conditions. In vivo, tFNAs successfully reduce RNV and inhibit VO in OIR model via the PI3K/AKT/mTOR/S6K pathway, while vascular endothelial growth factor fusion protein, Aflibercept, could reduce RNV but not inhibit VO. This study provides a theoretical basis for the further understanding of RNV and suggests that tFNAs might be a novel promising candidate for the treatment of blind-causing RNV.

Antidiabetic effect of sciadonic acid on type 2 diabetic mice through activating the PI3K-AKT signaling pathway and altering intestinal flora

Type 2 diabetes mellitus (T2DM) is a metabolic disease characterized by hyperglycemia. The aim of this work was to investigate the effect of sciadonic acid (SA) on disorders of glucolipid metabolism and intestinal flora imbalance and to further investigate its potential molecular mechanism of anti-diabetes. The experimental data indicated that SA could alleviate hyperlipidemia, insulin resistance, oxidative stress, the inflammatory response, repair liver function damage, and promote glycogen synthesis caused by T2DM. SA could also activate the PI3K/AKT/GLUT-2 signaling pathway, promote glucose metabolism gene expression, and maintain glucose homeostasis. Furthermore, 16S rRNA analysis revealed that SA could reduce the Firmicutes/Bacteroidota (F/B) ratio; promote norank_f__Muribaculaceae, Allobaculum, Akkermansia, and Eubacterium_siraeum_group proliferation; increase the levels of major short-chain fatty acids (SCFAs), such as acetic acid, propionic acid, and butyric acid; and maintain the homeostasis of the intestinal flora. In conclusion, these results suggested that SA could reshape the structural composition of intestinal microbes, activate the PI3K/AKT/GLUT2 pathway, improve insulin resistance, and decrease blood glucose levels.

Quantitative Proteomic Analysis of Serum Reveals MST1 as a Potential Candidate Biomarker in Spontaneously Diabetic Cynomolgus Monkeys

The prevalence of type 2 diabetes (T2DM) is increasing globally, creating essential demands for T2DM animal models for the study of disease pathogenesis, prevention, and therapy. A non-human primate model such as cynomolgus monkeys can develop T2DM spontaneously in an age-dependent way similar to humans. In this study, a data-independent acquisition-based quantitative proteomics strategy was employed to investigate the serum proteomic profiles of spontaneously diabetic cynomolgus monkeys compared with healthy controls. The results revealed significant differences in protein abundances. A total of 95 differentially expressed proteins (DEPs) were quantitatively identified in the current study, among which 31 and 64 proteins were significantly upregulated and downregulated, respectively. Bioinformatic analysis revealed that carbohydrate digestion and absorption was the top enriched pathway by the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Protein-protein interaction network analysis demonstrated that MST1 was identified as the most connected protein in the network and could be considered as the hub protein. MST1 was significantly and inversely associated with FSG and HbA1c. Furthermore, recent lines of evidence also indicate that MST1 acts as a crucial regulator in regulating hepatic gluconeogenesis to maintain metabolic homeostasis while simultaneously suppressing the inflammatory processes. In conclusion, our study provides novel insights into serum proteome changes in spontaneously diabetic cynomolgus monkeys and points out that the dysregulation of several DEPs may play an important role in the pathogenesis of T2DM.

Advances in regenerative medicine applications of tetrahedral framework nucleic acid-based nanomaterials: an expert consensus recommendation

With the emergence of DNA nanotechnology in the 1980s, self-assembled DNA nanostructures have attracted considerable attention worldwide due to their inherent biocompatibility, unsurpassed programmability, and versatile functions. Especially promising nanostructures are tetrahedral framework nucleic acids (tFNAs), first proposed by Turberfield with the use of a one-step annealing approach. Benefiting from their various merits, such as simple synthesis, high reproducibility, structural stability, cellular internalization, tissue permeability, and editable functionality, tFNAs have been widely applied in the biomedical field as three-dimensional DNA nanomaterials. Surprisingly, tFNAs exhibit positive effects on cellular biological behaviors and tissue regeneration, which may be used to treat inflammatory and degenerative diseases. According to their intended application and carrying capacity, tFNAs could carry functional nucleic acids or therapeutic molecules through extended sequences, sticky-end hybridization, intercalation, and encapsulation based on the Watson and Crick principle. Additionally, dynamic tFNAs also have potential applications in controlled and targeted therapies. This review summarized the latest progress in pure/modified/dynamic tFNAs and demonstrated their regenerative medicine applications. These applications include promoting the regeneration of the bone, cartilage, nerve, skin, vasculature, or muscle and treating diseases such as bone defects, neurological disorders, joint-related inflammatory diseases, periodontitis, and immune diseases.

Network exploration of gene signatures underlying low birth weight induced metabolic alterations

BACKGROUND

This study explored underlying gene signatures of low birth weight (LBW) by analyzing differentially expressed genes (DEGs) between LBW and normal birth weight (NBW) subjects.

METHODS

Subjects with different birth weight was collected from GEO database. P < .05 and | logFC | ≥ 1.0 were used for screening DEGs. David (2021 Update) was used to perform GO annotation and KEGG signaling pathway enrichment analysis. The protein-protein interaction network of DEGs was constructed using the STRING database, in which hub genes were mined through Cytoscape software.

RESULTS

A total of 326 DEGs were identified, including 287 up-regulated genes and 39 down-regulated genes. The GO biological processes enriched by DEGs mainly involved epidermal growth, keratinization and intermediate fibrous tissue. The DEGs were significantly enriched in intracellular insoluble membranes, desmosomes and extracellular space. Their molecular functions mainly focused on structural molecular activity, structural components of epidermis and structural components of cytoskeleton. PI3K/AKT signaling pathway and tight junction were highlighted as critical pathways enriched by DEGs. Ten hub genes which included KRT14, EGF, DSP, DSG1, KRT16, KRT6A, EPCAM, SPRR1B, PKP1, and PPL were identified from the constructed protein-protein interaction network.

CONCLUSION

A total of 326 DEGs and 10 hub genes were identified as candidates for metabolic disorders in LBW individuals. Our results indicated PI3K/AKT signaling pathway as an intrauterine adaptive mechanism for LBW individuals. We observed activated PI3K/AKT pathway in LBW individuals, which would promote growth and development at the early stage of life, but adversely introduce extra metabolic stress and thereby potentially induce metabolic disorders in adulthood.

In Vivo Assessment of the Effects of Mono-Carrier Encapsulated Fucoxanthin Nanoparticles on Type 2 Diabetic C57 Mice and Their Oxidative Stress

Fucoxanthin (FX) is a carotenoid from a marine origin that has an important role in our health, especially in the regulation and alleviation of type 2 diabetes. Its specific molecular structure makes it very unstable, which greatly affects its delivery in the body. In this study, FX was encapsulated in a mono-carrier using a hydrolyzed zein to form a nanocomplex with a stable structure and chemical properties (FZNP). Its stability was demonstrated by characterization and the efficacy of FX before and after encapsulation in alleviating diabetes in mice, which was evaluated by in vivo experiments. FZNP reduced the level of fasting blood glucose and restored it to normal levels in T2DM mice, which was not caused by a decrease in food intake, and effectively reduced oxidative stress in the organism. Both FX and FZNP repaired the hepatocyte and pancreatic β-cell damage, increased serum SOD and reduced INS values significantly, upregulated PI3K-AKT genes as well as CaMK and GNAs expression in the pancreas. FZNP increased ADPN and GSH-PX values more significantly and it decreased serum HOMA-IR and MDA values, upregulated GLUT2 expression, promoted glucose transport in pancreatic and hepatocytes, regulated glucose metabolism and glycogen synthesis with much superior effects than FX.

A Mini-Review of Diagnostic and Therapeutic Nano-Tools for Pancreatitis

Pancreatitis is an inflammatory reaction of pancreatic tissue digestion, edema, bleeding and even necrosis caused by activation of pancreatin due to various causes. In particular, patients with severe acute pancreatitis (SAP) often suffer from secondary infection, peritonitis and shock, and have a high mortality rate. Chronic pancreatitis (CP) can cause permanent damage to the pancreas. Due to the innate characteristics, structure and location of the pancreas, there is no effective treatment, only relief of symptoms. Especially, AP is an unpredictable and potentially fatal disease, and the timely diagnosis and treatment remains a major challenge. With the rapid development of nanomedicine technology, many potential tools can be used to address this problem. In this review, we have introduced the pathophysiological processes of pancreatitis to understanding its etiology and severity. Most importantly, the current progress in the diagnosis and treatment tools of pancreatitis based on nanomedicine is summarized and prospected.

Antioxidant Effect of Tyr-Ala Extracted from Zein on INS-1 Cells and Type 2 Diabetes High-Fat-Diet-Induced Mice

Type 2 diabetes mellitus (T2DM) is associated with an oxidative milieu that often leads to adverse health problems. Bioactive peptides of zein possess outstanding antioxidant activity; however, their effects on hyperglycemia-related oxidative stress remain elusive. In the present study, the dipeptide Tyr-Ala (YA), a functional peptide with typical health benefits, was applied to alleviate oxidative stress in pancreatic islets under hyperglycemic conditions. By detecting viability, antioxidant ability, and insulin secretion in INS-1 cells, YA showed excellent protection of INS-1 cells from H2O2 oxidative stress, erasing reactive oxygen species (ROS) and promoting insulin secretion. Moreover, by Western blotting, we found that YA can regulate the PI3K/Akt signaling pathway associated with glycometabolism. After establishing a T2DM mice model, we treated mice with YA and measured glucose, insulin, hemoglobin A1C (HbA1c), total cholesterol (TC), triglyceride (TG), and malonaldehyde (MDA) levels and activities of superoxide dismutase (SOD) and glutathione (GSH) from blood samples. We observed that YA could reduce the production of glucose, insulin, HbA1c, TC, TG, and MDA, in addition to enhancing the activities of SOD and GSH. YA could also repair the function of the kidneys and pancreas of T2DM mice. Along with the decline in fasting blood glucose, the oxidative stress in islets was alleviated in T2DM mice after YA administration. This may improve the health situation of diabetic patients in the future.

Therapeutic Effects of Self-Assembled Tetrahedral Framework Nucleic Acids on Liver Regeneration in Acute Liver Failure

Liver failure is a serious disease that is characterized by global hepatocyte necrosis. Hepatocyte proliferation and liver regeneration are critically important for the success of treatments for liver disease. Tetrahedral framework nucleic acids (TFNAs), which are widely used antioxidants and anti-inflammatory nanomaterials, activate multiple proliferation and prosurvival pathways. Therefore, the effects of a TFNA on hepatocyte proliferation and liver regeneration in mouse livers injured by 70% partial hepatectomy (PHx), acetaminophen overdose, and carbon tetrachloride were explored in this study. The TFNA, which was successfully self-assembled from four specifically designed ssDNAs, entered the body quickly and was taken up effectively by hepatocytes in the liver and could eventually be cleared by the kidneys. The TFNA promoted hepatocyte proliferation in vitro by activating the Notch and Wnt signaling pathways. In the three in vivo mouse models of liver injury, the TFNA attenuated the injuries and enhanced liver regeneration by regulating the cell cycle and the P53 signaling pathway. Therefore, by promoting hepatocyte proliferation and enhancing liver regeneration, the TFNA shows potential as an effective therapeutic agent for treating acute liver injury induced by 70% PHx and other factors, thereby preventing the progression to acute liver failure and reducing the associated mortality rate.

Pyroptosis and inflammasomes in diabetic wound healing

Diabetic wound is one of the complications of diabetes and is not easy to heal. It often evolves into chronic ulcers, and severe patients will face amputation. Compared with normal wounds, diabetic wounds have an increased proportion of pro-inflammatory cytokines that are detrimental to the normal healing response. The burden of this disease on patients and healthcare providers is overwhelming, and practical solutions for managing and treating diabetic wounds are urgently needed. Pyroptosis, an inflammatory type of programmed cell death, is usually triggered by the inflammasome. The pyroptosis-driven cell death process is primarily mediated by the traditional signaling pathway caused by caspase -1 and the non-classical signaling pathways induced by caspase -4/5/11. Growing evidence that pyroptosis promotes diabetic complications, including diabetic wounds. In addition, inflammation is thought to be detrimental to wound healing. It is worth noting that the activation of the NLRP3 inflammasome plays a crucial role in the recovery of diabetic wounds. This review has described the mechanisms of pyroptosis-related signaling pathways and their impact on diabetic wounds. It has discussed new theories and approaches to promote diabetic wound healing, as well as some potential compounds targeting pyroptosis and inflammasome signaling pathways that could be new approaches to treating diabetic wounds.

Functionalizing Framework Nucleic-Acid-Based Nanostructures for Biomedical Application

Strategies for functionalizing diverse tetrahedral framework nucleic acids (tFNAs) have been extensively explored since the first successful fabrication of tFNA by Turberfield. One-pot annealing of at least four DNA single strands is the most common method to prepare tFNA, as it optimizes the cost, yield, and speed of assembly. Herein, the focus is on four key merits of tFNAs and their potential for biomedical applications. The natural ability of tFNA to scavenge reactive oxygen species, along with remarkable enhancement in cellular endocytosis and tissue permeability based on its appropriate size and geometry, promotes cell-material interactions to direct or probe cell behavior, especially to treat inflammatory and degenerative diseases. Moreover, the structural programmability of tFNA enables the development of static tFNA-based nanomaterials via engineering of functional oligonucleotides or therapeutic molecules, and dynamic tFNAs via attachment of stimuli-responsive DNA apparatuses, leading to potential applications in targeted therapies, tissue regeneration, antitumor strategies, and antibacterial treatment. Although there are impressive performance and significant progress, the challenges and prospects of functionalizing tFNA-based nanostructures are still indicated in this review.

Identification of C21 Steroidal Glycosides from Gymnema sylvestre (Retz.) and Evaluation of Their Glucose Uptake Activities

Gymnema sylvestre (Retz.) Schult is a multi-purpose traditional medicine that has long been used for the treatment of various diseases. To discover the potential bioactive composition of G. sylvestre, a chemical investigation was thus performed. In this research, four new C21 steroidal glycosides sylvepregosides A-D (1-4) were isolated along with four known compounds, gymnepregoside H (5), deacetylkidjoladinin (6), gymnepregoside G (7) and gymnepregoside I (8), from the ethyl acetate fraction of G. sylvestre. The structures of the new compounds were established by extensive 1D and 2D nuclear magnetic resonance (NMR) spectra with mass spectroscopy data. Compounds 1-6 promoted glucose uptake by the range of 1.10- to 2.37-fold, respectively. Compound 1 showed the most potent glucose uptake, with 1.37-fold enhancement. Further study showed that compounds 1 and 5 could promote GLUT-4 fusion with the plasma membrane in L6 cells. The result attained in this study indicated that the separation and characterization of these compounds play an important role in the research and development of new anti-diabetic drugs and pharmaceutical industry.