The role of macrophages in obesity-associated islet inflammation and β-cell abnormalities

Probiotic for Pancreatic β-Cell Function in Type 2 Diabetes: A Randomized, Double-Blinded, Placebo-Controlled Clinical Trial

INTRODUCTION

Many clinical studies have proved the effectiveness of probiotics in metabolic disorders associated with insulin resistance. However, the impact of probiotic therapy on pancreatic β-cell function is ambiguous. The influence of probiotic supplementation vs. placebo on β-cell function in people with type 2 diabetes (T2D) was assessed in a double-blind, single-center, randomized, placebo-controlled trial (RCT).

METHODS

Sixty-eight patients with T2D were selected for participation in the RCT. Patients were randomly allocated to consumption of live multistrain probiotics or a placebo for 8 weeks, administered as a sachet formulation in double-blind treatment. The primary main outcome was the assessment of β-cell function as change in C-peptide and HOMA-β (homeostasis model assessment-estimated β-cell function), which was calculated using the HOMA2 calculator (Diabetes Trials Unit, University of Oxford). Secondary outcomes were the changes in glycemic control-related parameters, anthropomorphic variables, and cytokines levels. Analysis of covariance was used to assess the difference between groups.

RESULTS

Supplementation with live multiprobiotic was associated with slight significant improvement of β-cell function (HOMA-β increased from 32.48 ± 13.12 to 45.71 ± 25.18; p = 0.003) and reduction of fasting glucose level (13.03 ± 3.46 vs 10.66 ± 2.63 mmol/L and 234.63 ± 62.36 vs 192.07 ± 47.46 mg/dL; p < 0.001) and HbA1c (8.86 ± 1.28 vs 8.48 ± 1.22; p = 0.043) as compared to placebo. Probiotic therapy significantly affects chronic systemic inflammation in people with T2D by reducing pro-inflammatory cytokine levels.

CONCLUSIONS

Probiotic therapies modestly improved β-cell function in patients with T2D. Modulating the gut microbiota represents a new diabetes treatment and should be tested in more extensive studies.

TRIAL REGISTRATION

NCT05765292.

Asprosin, a novel glucogenic adipokine implicated in type 2 diabetes mellitus

Asprosin, encoded by penultimate two exons (exon 65 and exon 66) of the gene Fibrillin 1 (FBN1), has been recently discovered to be a novel hormone secreted by white adipose tissues during fasting. The glucose metabolism disorders are often accompanied by increased asprosin level. Previous research suggests that asprosin may contribute to the development of diabetes by regulating glucose homeostasis, appetite, insulin secretion, and insulin sensitivity. In this review, we summarize the recent findings from studies on asprosin and its association with Type 2 diabetes mellitus, and discusses its mechanisms from various aspects, so as to provide clinical diagnosis and treatment ideas for T2DM.

Functional screening and rational design of compounds targeting GPR132 to treat diabetes

Chronic inflammation due to islet-residing macrophages plays key roles in the development of type 2 diabetes mellitus. By systematically profiling intra-islet lipid-transmembrane receptor signalling in islet-resident macrophages, we identified endogenous 9(S)-hydroxy-10,12-octadecadienoic acid-G-protein-coupled receptor 132 (GPR132)-Gi signalling as a significant contributor to islet macrophage reprogramming and found that GPR132 deficiency in macrophages reversed metabolic disorders in mice fed a high-fat diet. The cryo-electron microscopy structures of GPR132 bound with two endogenous agonists, N-palmitoylglycine and 9(S)-hydroxy-10,12-octadecadienoic acid, enabled us to rationally design both GPR132 agonists and antagonists with high potency and selectivity through stepwise translational approaches. We ultimately identified a selective GPR132 antagonist, NOX-6-18, that modulates macrophage reprogramming within pancreatic islets, decreases weight gain and enhances glucose metabolism in mice fed a high-fat diet. Our study not only illustrates that intra-islet lipid signalling contributes to islet macrophage reprogramming but also provides a broadly applicable strategy for the identification of important G-protein-coupled receptor targets in pathophysiological processes, followed by the rational design of therapeutic leads for refractory diseases such as diabetes.

Signaling pathways in macrophages: molecular mechanisms and therapeutic targets

Macrophages play diverse roles in development, homeostasis, and immunity. Accordingly, the dysfunction of macrophages is involved in the occurrence and progression of various diseases, such as coronavirus disease 2019 and atherosclerosis. The protective or pathogenic effect that macrophages exert in different conditions largely depends on their functional plasticity, which is regulated via signal transduction such as Janus kinase-signal transducer and activator of transcription, Wnt and Notch pathways, stimulated by environmental cues. Over the past few decades, the molecular mechanisms of signaling pathways in macrophages have been gradually elucidated, providing more alternative therapeutic targets for diseases treatment. Here, we provide an overview of the basic physiology of macrophages and expound the regulatory pathways within them. We also address the crucial role macrophages play in the pathogenesis of diseases, including autoimmune, neurodegenerative, metabolic, infectious diseases, and cancer, with a focus on advances in macrophage-targeted strategies exploring modulation of components and regulators of signaling pathways. Last, we discuss the challenges and possible solutions of macrophage-targeted therapy in clinical applications. We hope that this comprehensive review will provide directions for further research on therapeutic strategies targeting macrophage signaling pathways, which are promising to improve the efficacy of disease treatment.

Tracing the evolving dynamics and research hotspots of microbiota and immune microenvironment from the past to the new era

Gut microbiota can regulate many physiological processes within gastrointestinal tract and other distal sites. Dysbiosis may not only influence chronic diseases like the inflammatory bowel disease (IBD), metabolic disease, tumor and its therapeutic efficacy, but also deteriorate acute injuries. This article aims to review the documents in this field and summarize the research hotspots as well as developing processes. Gut microbiota and immune microenvironment-related documents from 1976 to 2022 were obtained from the Web of Science Core Collection database. Bibliometrics was used to assess the core authors and journals, most contributive countries and affiliations together with hotspots in this field and keyword co-occurrence analysis. Data were visualized to help comprehension. Nine hundred and twelve documents about gut microbiota and immune microenvironment were retrieved, and the annual publications increased gradually. The most productive author, country, and affiliation were "Zitvogel L," USA and "UNIV TEXAS MD ANDERSON CANC CTR," respectively. FRONTIERS IN IMMUNOLOGY, CANCERS, and INTERNATIONAL JOURNAL OF MOLECULAR SCIENCE were the periodicals with most publications. Keyword co-occurrence analysis identified three clusters, including gut microbiota, inflammation, and IBD. Combined with the visualized analysis of documents and keyword co-occurrence as well as literature reading, we recognized three key topics of gut microbiota: cancer and therapy; immunity, inflammation and IBD; acute injuries and metabolic diseases. This article revealed researches on gut microbiota and immune microenvironment were growing. More attention should be given to the latest hotspots like gut microbiota, inflammation, IBD, cancer and immunotherapy, acute traumas, and metabolic diseases.IMPORTANCEGut microbiota can regulate many physiological processes within gastrointestinal tract and other distal sites. Dysbiosis may not only influence chronic diseases like inflammatory bowel disease (IBD), metabolic disease, tumor and its therapeutic efficacy, but also deteriorate acute injuries. While the application of bibliometrics in the field of gut microbiota and immune microenvironment still remains blank, which focused more on the regulation of the gut microbiota on the immune microenvironment of different kinds of diseases. Here, we intended to review and summarize the presented documents in gut microbiota and immune microenvironment field by bibliometrics. And we revealed researches on gut microbiota and immune microenvironment were growing. More attention should be given to the latest hotspots like gut microbiota, inflammation, IBD, cancer and immunotherapy, acute traumas, and metabolic diseases.

Association of remnant cholesterol with hypertension, type 2 diabetes, and their coexistence: the mediating role of inflammation-related indicators

PURPOSE

Cholesterol metabolism is a risk factor for cardiovascular disease, and recent studies have shown that cholesterol metabolism poses a residual risk of cardiovascular disease even when conventional lipid risk factors are in the optimal range. The association between remnant cholesterol (RC) and cardiovascular disease has been demonstrated; however, its association with hypertension, type 2 diabetes mellitus (T2DM), and the concomitance of the two diseases requires further study. This study aimed to evaluate the association of RC with hypertension, T2DM, and both in a large sample of the U.S. population, and to further explore the potential mechanisms involved.

METHODS

This cross-sectional study used data from the 2005-2018 cycles of the National Health and Nutrition Examination Survey (N = 17,749). Univariable and multivariable logistic regression analyses were performed to explore the relationships of RC with hypertension, T2DM, and both comorbidities. A restricted cubic spline regression model was used to reveal the dose effect. Mediation analyses were performed to explore the potential mediating roles of inflammation-related indicators in these associations.

RESULTS

Of the 17,749 participants included (mean [SD] age: 41.57 [0.23] years; women: 8983 (50.6%), men: 8766 (49.4%)), the prevalence of hypertension, T2DM, and their co-occurrence was 32.6%, 16.1%, and 11.0%, respectively. Higher RC concentrations were associated with an increased risk of hypertension, T2DM, and their co-occurrence (adjusted odds ratios for per unit increase in RC were 1.068, 2.259, and 2.362, and 95% confidence intervals were 1.063-1.073, 1.797-2.838, and 1.834-3.041, respectively), with a linear dose-response relationship. Even when conventional lipids were present at normal levels, positive associations were observed. Inflammation-related indicators (leukocytes, lymphocytes, monocytes, and neutrophils) partially mediated these associations. Among these, leukocytes had the greatest mediating effect (10.8%, 14.5%, and 14.0%, respectively).

CONCLUSION

The results of this study provide evidence that RC is associated with the risk of hypertension, T2DM, and their co-occurrence, possibly mediated by an inflammatory response.

The impact of microbiota-derived short-chain fatty acids on macrophage activities in disease: Mechanisms and therapeutic potentials

Short-chain fatty acids (SCFAs) derived from the fermentation of carbohydrates by gut microbiota play a crucial role in regulating host physiology. Among them, acetate, propionate, and butyrate are key players in various biological processes. Recent research has revealed their significant functions in immune and inflammatory responses. For instance, butyrate reduces the development of interferon-gamma (IFN-γ) generating cells while promoting the development of regulatory T (Treg) cells. Propionate inhibits the initiation of a Th2 immune response by dendritic cells (DCs). Notably, SCFAs have an inhibitory impact on the polarization of M2 macrophages, emphasizing their immunomodulatory properties and potential for therapeutics. In animal models of asthma, both butyrate and propionate suppress the M2 polarization pathway, thus reducing allergic airway inflammation. Moreover, dysbiosis of gut microbiota leading to altered SCFA production has been implicated in prostate cancer progression. SCFAs trigger autophagy in cancer cells and promote M2 polarization in macrophages, accelerating tumor advancement. Manipulating microbiota- producing SCFAs holds promise for cancer treatment. Additionally, SCFAs enhance the expression of hypoxia-inducible factor 1 (HIF-1) by blocking histone deacetylase, resulting in increased production of antibacterial effectors and improved macrophage-mediated elimination of microorganisms. This highlights the antimicrobial potential of SCFAs and their role in host defense mechanisms. This comprehensive review provides an in-depth analysis of the latest research on the functional aspects and underlying mechanisms of SCFAs in relation to macrophage activities in a wide range of diseases, including infectious diseases and cancers. By elucidating the intricate interplay between SCFAs and macrophage functions, this review aims to contribute to the understanding of their therapeutic potential and pave the way for future interventions targeting SCFAs in disease management.

Engineered Cytokine-Primed Extracellular Vesicles with High PD-L1 Expression Ameliorate Type 1 Diabetes

Type 1 diabetes (T1D), which is a chronic autoimmune disease, results from the destruction of insulin-producing β cells targeted by autoreactive T cells. The recent discovery that mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) function as therapeutic tools for autoimmune conditions has attracted substantial attention. However, the in vivo distribution and therapeutic effects of MSC-EVs potentiated by pro-inflammatory cytokines in the context of T1D have yet to be established. Here, it is reported that hexyl 5-aminolevulinate hydrochloride (HAL)-loaded engineered cytokine-primed MSC-EVs (H@TI-EVs) with high expression of immune checkpoint molecule programmed death-legend 1 (PD-L1) exert excellent inflammatory targeting and immunosuppressive effects for T1D imaging and therapy. The accumulated H@TI-EVs in injured pancreas not only enabled the fluorescence imaging and tracking of TI-EVs through the intermediate product protoporphyrin (PpIX) generated by HAL, but also promoted the proliferative and anti-apoptotic effects of islet β cells. Further analysis revealed that H@TI-EVs exhibited an impressive ability to reduce CD4+ T cell density and activation through the PD-L1/PD-1 axis, and induced M1-to-M2 macrophage transition to reshape the immune microenvironment, exhibiting high therapeutic efficiency in mice with T1D. This work identifies a novel strategy for the imaging and treatment of T1D with great potential for clinical application.

Pancreatic β-Cell Apoptosis in Normoglycemic Rats is Due to Mitochondrial Translocation of p53-Induced by the Consumption of Sugar-Sweetened Beverages

Overstimulation of pancreatic β-cells can lead to dysfunction and death, prior to the clinical manifestations of type 2 diabetes (T2D). The excessive consumption of carbohydrates induces metabolic alterations that can affect the functions of the β-cells and cause their death. We analyzed the role of p53 in pancreatic β cell death in carbohydrate-supplemented Sprague Dawley rats. For four months, the animals received drinking water containing either 40% sucrose or 40% fructose. The glucose tolerance test was performed at week 15. Apoptosis was assessed with the TUNEL assay (TdT-mediated dUTP-nick end-labeling). Bax, p53, and insulin were assessed by Western blotting, immunofluorescence, and real-time quantitative PCR. Insulin, triacylglycerol, and serum glucose and fatty acids in pancreatic tissue were measured. Carbohydrate consumption promotes apoptosis and mobilization of p53 from the cytosol to rat pancreatic β-cell mitochondria before blood glucose rises. An increase in p53, miR-34a, and Bax mRNA was also detected (P < 0.001) in the sucrose group. As well as hypertriglyceridemia, hyperinsulinemia, glucose intolerance, insulin resistance, visceral fat accumulation, and increased pancreatic fatty acids in the sucrose group. Carbohydrate consumption increases p53 and its mobilization into β-cell mitochondria and coincides with the increased rate of apoptosis, which occurs before serum glucose levels rise.

Biomarkers of obesity-mediated insulin resistance: focus on microRNAs

Obesity and metabolic syndromes are becoming increasingly prevalent worldwide. Insulin resistance (IR) is a common complication of obesity. However, IR occurrence varies across individuals with obesity and may involve epigenetic factors. To rationalize the allocation of healthcare resources, biomarkers for the early risk stratification of individuals with obesity should be identified. MicroRNAs (miRNAs) are closely associated with metabolic diseases and involved in epigenetic regulation. In this review, we have summarized the changes in miRNA expression in the peripheral circulation and tissues of patients and animals with obesity-associated IR over the last 5 years and identified several candidate biomarkers that predict obesity-related IR. There are areas for improvement in existing studies. First, more than the predictive validity of a single biomarker is required, and a biomarker panel needs to be formed. Second, miRNAs are often studied in isolation and do not form a network of signaling pathways. We believe that early biomarkers can help clinicians accurately predict individuals prone to obesity-related IR at an early stage. Epigenetic regulation may be one of the underlying causes of different clinical outcomes in individuals with obesity. Future studies should focus on objectively reflecting the differences in miRNA profile expression in individuals with obesity-related IR, which may help identify more reliable biomarkers. Understanding the metabolic pathways of these miRNAs can help design new metabolic risk prevention and management strategies, and support the development of drugs to treat obesity and metabolic disorders.

Stress-induced pseudokinase TRB3 augments IL1β signaling by interacting with Flightless homolog 1

Interleukin-1β is one of the most potent inducers of beta cell inflammation in the lead-up to type 1 diabetes. We have previously reported that IL1β-stimulated pancreatic islets from mice with genetic ablation of stress-induced pseudokinase TRB3(TRB3KO) show attenuated activation kinetics for the MAP3K MLK3 and JNK stress kinases. However, JNK signaling constitutes only a portion of the cytokine-induced inflammatory response. Here we report that TRB3KO islets also show a decrease in amplitude and duration of IL1β-induced phosphorylation of TAK1 and IKK, kinases that drive the potent NF-κB proinflammatory signaling pathway. We observed that TRB3KO islets display decreased cytokine-induced beta cell death, preceded by a decrease in select downstream NF-κB targets, including iNOS/NOS2 (inducible nitric oxide synthase), a mediator of beta cell dysfunction and death. Thus, loss of TRB3 attenuates both pathways required for a cytokine-inducible, proapoptotic response in beta cells. In order to better understand the molecular basis of TRB3-enhanced, post-receptor IL1β signaling, we interrogated the TRB3 interactome using coimmunoprecipitation followed by mass spectrometry to identify immunomodulatory protein Flightless homolog 1 (Fli1) as a novel, TRB3-interacting protein. We show that TRB3 binds and disrupts Fli1-dependent sequestration of MyD88, thereby increasing availability of this most proximal adaptor required for IL1β receptor-dependent signaling. Fli1 sequesters MyD88 in a multiprotein complex resulting in a brake on the assembly of downstream signaling complexes. By interacting with Fli1, we propose that TRB3 lifts the brake on IL1β signaling to augment the proinflammatory response in beta cells.

Improved Insulin Secretion Response and Beta-cell Function Correlated with Increased Prolactin Levels After Laparoscopic Sleeve Gastrectomy in Morbidly Obese Patients with Acanthosis Nigricans

OBJECTIVE

To explore insulin secretion patterns, β-cell function, and serum prolactin (PRL) concentrations in Chinese morbidly obese patients with Acanthosis nigricans (AN) and their alterations after laparoscopic sleeve gastrectomy (LSG).

METHODS

A total of 138 morbidly obese subjects undergoing LSG were categorized as simple obesity without AN (OB group, n = 55) and obesity with AN (AN group, n = 83). Oral glucose tolerance test (OGTT), PRL, and related metabolic indices were performed pre- and 12 months post-LSG. Insulin secretion patterns were derived from insulin secretion peak time during OGTT: type I (peak at 30 or 60 min) and type II (peak at 120 or 180 min).

RESULTS

Preoperatively, AN group showed significantly higher proportions of type II insulin secretion pattern, fasting insulin (FINS), and homeostatic model assessment of insulin resistance (HOMA-IR) whereas lower oral glucose insulin sensitivity (OGIS), insulinogenic index (IGI), and disposition index (DI) than OB group, which were improved significantly at 12 months postoperatively in both groups, more pronounced in AN group. Intriguingly, serum PRL declined substantially in AN group than OB group at baseline whereas elevated only in the AN group post-LSG. After adjusting for confounding factors, elevated PRL correlated significantly with increased IGI and DI, and decreased HOMA-IR in both genders, as well as increased OGIS in females, which was detected only in the AN group CONCLUSION: Morbidly obese patients with AN presented delayed insulin secretion response, impaired insulin secretion, and β-cell dysfunction, which were significantly improved by LSG and might benefit from elevated PRL.

Visualizing temporal dynamics and research trends of macrophage-related diabetes studies between 2000 and 2022: a bibliometric analysis

Background

Macrophages are considered an essential source of inflammatory cytokines, which play a pivotal role in the development of diabetes and its sequent complications. Therefore, a better understanding of the intersection between the development of diabetes and macrophage is of massive importance.

Objectives

In this study, we performed an informative bibliometric analysis to enlighten relevant research directions, provide valuable metrics for financing decisions, and help academics to gain a quick understanding of the current macrophage-related diabetes studies knowledge domain.

Methods

The Web of Science Core Collection database was used for literature retrieval and dataset export. Bibliometrix R-package was performed to conduct raw data screening, calculating, and visualizing.

Results

Between 2000 and 2022, the annual publication and citation trends steadily increased. Wu Yonggui was the scholar with the most published papers in this field. The institute with the highest number of published papers was the University of Michigan. The most robust academic collaboration was observed between China and the United States of America. Diabetologia was the journal that published the most relevant publications. The author's keywords with the highest occurrences were "inflammation", "diabetic nephropathy", and "obesity". In addition, "Macrophage polarization" was the current motor topic with potential research prospects.

Conclusions

These comprehensive and visualized bibliometric results summarized the significant findings in macrophage-related diabetes studies over the past 20 years. It would enlighten subsequent studies from a macro viewpoint and is also expected to strengthen investment policies in future macrophage-related diabetes studies.

Efferocytosis: An Emerging Therapeutic Strategy for Type 2 Diabetes Mellitus and Diabetes Complications

Increasing evidence indicates that chronic, low-grade inflammation is a significant contributor to the fundamental pathogenesis of type 2 diabetes mellitus (T2DM). Efferocytosis, an effective way to eliminate apoptotic cells (ACs), plays a critical role in inflammation resolution. Massive accumulation of ACs and the proliferation of persistent inflammation caused by defective efferocytosis have been proven to be closely associated with pancreatic islet β cell destruction, adipose tissue inflammation, skeletal muscle dysfunction, and liver metabolism abnormalities, which together are considered the most fundamental pathological mechanism underlying T2DM. Therefore, here we outline the association between the molecular mechanisms of efferocytosis in glucose homeostasis, T2DM, and its complications, and we analyzed the present constraints and potential future prospects for therapeutic targets in T2DM and its complications.

Selenium Nanodots (SENDs) as Antioxidants and Antioxidant-Prodrugs to Rescue Islet β Cells in Type 2 Diabetes Mellitus by Restoring Mitophagy and Alleviating Endoplasmic Reticulum Stress

Preventing islet β-cells death is crucial for treating type 2 diabetes mellitus (T2DM). Currently, clinical drugs are being developed to improve the quality of T2DM care and self-care, but drugs focused on reducing islets β-cell death are lacking. Given that β-cell death in T2DM is dominated ultimately by excessive reactive oxygen species (ROS), eliminating excessive ROS in β-cells is a highly promising therapeutic strategy. Nevertheless, no antioxidants have been approved for T2DM therapy because most of them cannot meet the long-term and stable elimination of ROS in β-cells without eliciting toxic side-effects. Here, it is proposed to restore the endogenous antioxidant capacity of β-cells to efficiently prevent β-cell death using selenium nanodots (SENDs), a prodrug of the antioxidant enzyme glutathione peroxidase 1 (GPX1). SENDs not only scavenge ROS effectively, but also "send" selenium precisely to β-cells with ROS response to greatly enhance the antioxidant capacity of β-cells by increasing GPX1 expression. Therefore, SENDs greatly rescue β-cells by restoring mitophagy and alleviating endoplasmic reticulum stress (ERS), and demonstrate much stronger efficacy than the first-line drug metformin for T2DM treatment. Overall, this strategy highlights the great clinical application prospects of SENDs, offering a paradigm for an antioxidant enzyme prodrug for T2DM treatment.

Shared biological mechanisms of depression and obesity: focus on adipokines and lipokines

Depression and obesity are both common disorders currently affecting public health, frequently occurring simultaneously within individuals, and the relationship between these disorders is bidirectional. The association between obesity and depression is highly co-morbid and tends to significantly exacerbate metabolic and related depressive symptoms. However, the neural mechanism under the mutual control of obesity and depression is largely inscrutable. This review focuses particularly on alterations in systems that may mechanistically explain the in vivo homeostatic regulation of the obesity and depression link, such as immune-inflammatory activation, gut microbiota, neuroplasticity, HPA axis dysregulation as well as neuroendocrine regulators of energy metabolism including adipocytokines and lipokines. In addition, the review summarizes potential and future treatments for obesity and depression and raises several questions that need to be answered in future research. This review will provide a comprehensive description and localization of the biological connection between obesity and depression to better understand the co-morbidity of obesity and depression.

Continuous glucose monitoring in a healthy population: understanding the post-prandial glycemic response in individuals without diabetes mellitus

Continuous glucose monitoring has become a common adjunct in the management of Diabetes Mellitus. However, there has been a recent trend among individuals without diabetes using these devices as a means of monitoring their health. The increased visibility of glucose data has allowed users to study the effect lifestyle has upon post-prandial glucose levels. Although post-prandial hyperglycemia is well understood in the setting of diabetes, its impact in individuals without diabetes is less well defined. This article reviews the factors which contribute to post-prandial hyperglycemia in individuals without diabetes and how the data obtained from continuous glucose monitoring can be used to improve an individual's metabolic health.

Physiopathological mechanisms related to inflammation in obesity and type 2 diabetes mellitus

Overweight, obesity, and type 2 diabetes mellitus pose global health problems that are ever-increasing. A chronic low-grade inflammatory status and the presence of various pro-inflammatory markers either in circulation or within dysfunctional metabolic tissues are well established. The presence of these factors can, to some extent, predict disease development and progression. A central role is played by the presence of dysfunctional adipose tissue, liver dysfunction, and skeletal muscle dysfunction, which collectively contribute to the increased circulatory levels of proinflammatory factors. Weight loss and classical metabolic interventions achieve a decrease in many of these factors’ circulating levels, implying that a better understanding of the processes or even the modulation of inflammation may alleviate these diseases. This review suggests that inflammation plays a significant role in the development and progression of these conditions and that measuring inflammatory markers may be useful for assessing disease risk and development of future treatment methods.

Oxidative stress: roles in skeletal muscle atrophy

Oxidative stress, inflammation, mitochondrial dysfunction, reduced protein synthesis, and increased proteolysis are all critical factors in the process of muscle atrophy. In particular, oxidative stress is the key factor that triggers skeletal muscle atrophy. It is activated in the early stages of muscle atrophy and can be regulated by various factors. The mechanisms of oxidative stress in the development of muscle atrophy have not been completely elucidated. This review provides an overview of the sources of oxidative stress in skeletal muscle and the correlation of oxidative stress with inflammation, mitochondrial dysfunction, autophagy, protein synthesis, proteolysis, and muscle regeneration in muscle atrophy. Additionally, the role of oxidative stress in skeletal muscle atrophy caused by several pathological conditions, including denervation, unloading, chronic inflammatory diseases (diabetes mellitus, chronic kidney disease, chronic heart failure, and chronic obstructive pulmonary disease), sarcopenia, hereditary neuromuscular diseases (spinal muscular atrophy, amyotrophic lateral sclerosis, and Duchenne muscular dystrophy), and cancer cachexia, have been discussed. Finally, this review proposes the alleviation oxidative stress using antioxidants, Chinese herbal extracts, stem cell and extracellular vesicles as a promising therapeutic strategy for muscle atrophy. This review will aid in the development of novel therapeutic strategies and drugs for muscle atrophy.

Structure-activity relationship, bioactivities, molecular mechanisms, and clinical application of nuciferine on inflammation-related diseases

Nuciferine aporphine alkaloid mainly exists in Nelumbo nucifera Gaertn and is a beneficial to human health, such as anti-obesity, lowering blood lipid, prevention of diabetes and cancer, closely associated with inflammation. Importantly, nuciferine may contribute to its bioactivities by exerting intense anti-inflammatory activities in multiple models. However, no review has summarized the anti-inflammatory effect of nuciferine. This review critically summarized the information regarding the structure-activity relationships of dietary nuciferine. Moreover, biological activities and clinical application on inflammation-related diseases, such as obesity, diabetes, liver, cardiovascular diseases, and cancer, as well as their potential mechanisms, involving oxidative stress, metabolic signaling, and gut microbiota has been reviewed. The current work provides a better understanding of the anti-inflammation properties of nuciferine against multiple diseases, thereby improving the utilization and application of nuciferine-containing plants across functional food and medicine.

Endocrine disruptors in plastics alter β-cell physiology and increase the risk of diabetes mellitus

Plastic pollution breaks a planetary boundary threatening wildlife and humans through its physical and chemical effects. Of the latter, the release of endocrine disrupting chemicals (EDCs) has consequences on the prevalence of human diseases related to the endocrine system. Bisphenols (BPs) and phthalates are two groups of EDCs commonly found in plastics that migrate into the environment and make low-dose human exposure ubiquitous. Here we review epidemiological, animal, and cellular studies linking exposure to BPs and phthalates to altered glucose regulation, with emphasis on the role of pancreatic β-cells. Epidemiological studies indicate that exposure to BPs and phthalates is associated with diabetes mellitus. Studies in animal models indicate that treatment with doses within the range of human exposure decreases insulin sensitivity and glucose tolerance, induces dyslipidemia, and modifies functional β-cell mass and serum levels of insulin, leptin, and adiponectin. These studies reveal that disruption of β-cell physiology by EDCs plays a key role in impairing glucose homeostasis by altering the mechanisms used by β-cells to adapt to metabolic stress such as chronic nutrient excess. Studies at the cellular level demonstrate that BPs and phthalates modify the same biochemical pathways involved in adaptation to chronic excess fuel. These include changes in insulin biosynthesis and secretion, electrical activity, expression of key genes, and mitochondrial function. The data summarized here indicate that BPs and phthalates are important risk factors for diabetes mellitus and support a global effort to decrease plastic pollution and human exposure to EDCs.

Hypolipidemic and Anti-Inflammatory Effects of Curcuma longa-Derived Bisacurone in High-Fat Diet-Fed Mice

Turmeric (Curcuma longa) contains various compounds that potentially improve health. Bisacurone is a turmeric-derived compound but has been less studied compared to other compounds, such as curcumin. In this study, we aimed to evaluate the anti-inflammatory and lipid-lowering effects of bisacurone in high-fat diet (HFD)-fed mice. Mice were fed HFD to induce lipidemia and orally administered bisacurone daily for two weeks. Bisacurone reduced liver weight, serum cholesterol and triglyceride levels, and blood viscosity in mice. Splenocytes from bisacurone-treated mice produced lower levels of the pro-inflammatory cytokines IL-6 and TNF-α upon stimulation with a toll-like receptor (TLR) 4 ligand, lipopolysaccharide (LPS), and TLR1/2 ligand, Pam3CSK4, than those from untreated mice. Bisacurone also inhibited LPS-induced IL-6 and TNF-α production in the murine macrophage cell line, RAW264.7. Western blot analysis revealed that bisacurone inhibited the phosphorylation of IKKα/β and NF-κB p65 subunit, but not of the mitogen-activated protein kinases, p38 kinase and p42/44 kinases, and c-Jun N-terminal kinase in the cells. Collectively, these results suggest that bisacurone has the potential to reduce serum lipid levels and blood viscosity in mice with high-fat diet-induced lipidemia and modulate inflammation via inhibition of NF-κB-mediated pathways.

Beta Cell Dysfunction in Youth- and Adult-Onset Type 2 Diabetes: An Extensive Narrative Review with a Special Focus on the Role of Nutrients

Traditionally a disease of adults, type 2 diabetes (T2D) has been increasingly diagnosed in youth, particularly among adolescents and young adults of minority ethnic groups. Especially, during the recent COVID-19 pandemic, obesity and prediabetes have surged not only in minority ethnic groups but also in the general population, further raising T2D risk. Regarding its pathogenesis, a gradually increasing insulin resistance due to central adiposity combined with a progressively defective β-cell function are the main culprits. Especially in youth-onset T2D, a rapid β-cell activity decline has been observed, leading to higher treatment failure rates, and early complications. In addition, it is well established that both the quantity and quality of food ingested by individuals play a key role in T2D pathogenesis. A chronic imbalance between caloric intake and expenditure together with impaired micronutrient intake can lead to obesity and insulin resistance on one hand, and β-cell failure and defective insulin production on the other. This review summarizes our evolving understanding of the pathophysiological mechanisms involved in defective insulin secretion by the pancreatic islets in youth- and adult-onset T2D and, further, of the role various micronutrients play in these pathomechanisms. This knowledge is essential if we are to curtail the serious long-term complications of T2D both in pediatric and adult populations.

MicroRNA-126 regulates macrophage polarization to prevent the resorption of alveolar bone in diabetic periodontitis

OBJECTIVE

This study aims to investigate the effects of microRNA-126 (miR-126) on the macrophage polarization in vitro and alveolar bone resorption in vivo.

DESIGN

The relationship between miR-126 and MEK/ERK kinase 2 (MEKK2) was confirmed by dual-luciferase reporter assay. Real-time quantitative polymerase chain reaction, enzyme-linked immunosorbent assay or Western blot was used to detect the changes of miR-126, inducible nitric oxide synthase (iNOS), arginase-1 (Arg-1), tumor necrosis factor (TNF)-α, interleukin (IL)-10, MEKK2 and MEKK2-related pathways: mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) in RAW264.7 macrophages challenged with Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS) and/or high glucose and/or miR-126 mimic. In mice with diabetic periodontitis, the expressions of iNOS and Arg-1 in gingiva, and alveolar bone level were detected after miR-126 mimic injection.

RESULTS

MiR-126 could directly bind with MEKK2 3'-untranslated region (UTR). MEKK2, phosphorylation of NF-κB and MAPK signaling proteins, TNF-α and iNOS increased (P < 0.05), while miR-126, Arg-1 and IL-10 were inhibited (P < 0.05) in macrophage challenged with high glucose and/or P. gingivalis LPS, however, miR-126 mimic reversed these effects (P < 0.05). The expressions of iNOS in gingiva and alveolar bone resorption were elevated (P < 0.05), the expression of Arg-1 in gingiva decreased (P < 0.05) in mice with diabetic periodontitis, which could be inhibited by miR-126 mimic.

CONCLUSIONS

miR-126 might prevent alveolar bone resorption in diabetic periodontitis and inhibit macrophage M1 polarization via regulating MEKK2 signaling pathway.

Pancreatic β-cell dysfunction in type 2 diabetes: Implications of inflammation and oxidative stress

Insulin resistance and pancreatic β-cell dysfunction are major pathological mechanisms implicated in the development and progression of type 2 diabetes (T2D). Beyond the detrimental effects of insulin resistance, inflammation and oxidative stress have emerged as critical features of T2D that define β-cell dysfunction. Predominant markers of inflammation such as C-reactive protein, tumor necrosis factor alpha, and interleukin-1β are consistently associated with β-cell failure in preclinical models and in people with T2D. Similarly, important markers of oxidative stress, such as increased reactive oxygen species and depleted intracellular antioxidants, are consistent with pancreatic β-cell damage in conditions of T2D. Such effects illustrate a pathological relationship between an abnormal inflammatory response and generation of oxidative stress during the progression of T2D. The current review explores preclinical and clinical research on the patho-logical implications of inflammation and oxidative stress during the development of β-cell dysfunction in T2D. Moreover, important molecular mechanisms and relevant biomarkers involved in this process are discussed to divulge a pathological link between inflammation and oxidative stress during β-cell failure in T2D. Underpinning the clinical relevance of the review, a systematic analysis of evidence from randomized controlled trials is covered, on the potential therapeutic effects of some commonly used antidiabetic agents in modulating inflammatory makers to improve β-cell function.

Visnagin Attenuates Gestational Diabetes Mellitus in Streptozotocin-induced Diabetic Pregnant Rats via Regulating Dyslipidemia, Oxidative Stress, and Inflammatory Response

Background:

Gestational diabetes mellitus (GDM) is a condition of glucose intolerance and insulin resistance only diagnosed during pregnancy. GDM has exhibited several adverse effects on both mother and offspring. The current research focuses on discovering visnagin’s beneficial properties against the streptozotocin (STZ)-induced GDM in rats via alleviating the inflammation and oxidative stress.

Materials and Methods:

GDM was caused in the pregnant rats by the administration of 25 mg/kg of STZ by the intraperitoneal route and then treated with 20 mg/kg of visnagin for 20 consecutive days. The rats’ body weight was measured, and fasting blood glucose (FBG) status was determined using a standard glucometer. The contents of total cholesterol (TCh), triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were assessed using kits. The MDA level, total antioxidant capacity (TAC) status, and activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione S-transferase (GST) were determined using assay kits. Kits also assessed the contents of TNF-α and IL-1β. The contents of TNF-α and IL-1β effectively improved the body weight and decreased the FBG status in the GDM rats. The visnagin also decreased the TCh, TG, and LDL, and elevated the HDL content. The content of MDA was decreased and the visnagin treatment increased SOD, CAT, GST, and GPx, and the visnagin treatment increased SOD, CAT, GST, and GPx activities SOD, CAT, GST, and GPx activities. The visnagin effectively decreased the STZ-induced histopathological alterations in the pancreas.

Conclusion:

Altogether, our investigation results suggest a beneficial role visnagin against STZ-induced GDM in rats via inhibiting the inflammatory responses. Hence, it can be a talented therapeutic candidate for the successful management of GDM.

Clinical expert consensus on the assessment and protection of pancreatic islet β-cell function in type 2 diabetes mellitus

Islet β-cell dysfunction is a basic pathophysiological characteristic of type 2 diabetes mellitus (T2DM). Appropriate assessment of islet β-cell function is beneficial to better management of T2DM. Protecting islet β-cell function is vital to delay the progress of type 2 diabetes mellitus. Therefore, the Pancreatic Islet β-cell Expert Panel of the Chinese Diabetes Society and Endocrinology Society of Jiangsu Medical Association organized experts to draft the "Clinical expert consensus on the assessment and protection of pancreatic islet β-cell function in type 2 diabetes mellitus." This consensus suggests that β-cell function can be clinically assessed using blood glucose-based methods or methods that combine blood glucose and endogenous insulin or C-peptide levels. Some measures, including weight loss and early and sustained euglycemia control, could effectively protect islet β-cell function, and some newly developed drugs, such as Sodium-glucose cotransporter-2 inhibitor and Glucagon-like peptide-1 receptor agonists, could improve islet β-cell function, independent of glycemic control.

Sodium butyrate attenuate hyperglycemia-induced inflammatory response and renal injury in diabetic mice

The activation of the monocyte-macrophage system and the damage to the renal and pancreatic tissue are common complications in patients with diabetes induced by hyper-glycemia. This study aimed to evaluate the effect and mechanism of butyrate (NaB), a metabolite of intestinal flora, on inhibiting the inflammatory response of human monocyte-macrophages (THP-1 cells) induced by high glucose and the damage of pancreatic and renal tissue in diabetic mice. The results showed that high concentration glucose significantly up-regulated the expressions of IL-1β, TNF-α, and NLRP3 in THP-1 cells and mouse spleen, and that NaB could inhibit the overexpression of those genes. The abundance of Beclin-1, LC3B and reactive oxygen species (ROS) in THP-1 cells is increased due to the high glucose concentration, and NaB can inhibit the genes responsible for upregulating the expression. In diabetic mice, vacuolar degeneration of renal tubules was observed. Then we observed that some of the epithelial cells of the renal tubules were exfoliated and some formed tubules. NaB could alleviate these pathological lesions, but NaB cannot alleviate pancreatic injury. Our results indicated that NaB could be used for the prevention and adjuvant treatment of diabetic kidney injury.

Pancreas-Liver-Adipose Axis: Target of Environmental Cadmium Exposure Linked to Metabolic Diseases

Cadmium has been well recognized as a critical toxic agent in acute and chronic poisoning cases in occupational and nonoccupational settings and environmental exposure situations. Cadmium is released into the environment after natural and anthropogenic activities, particularly in contaminated and industrial areas, causing food pollution. In the body, cadmium has no biological activity, but it accumulates primarily in the liver and kidney, which are considered the main targets of its toxicity, through oxidative stress and inflammation. However, in the last few years, this metal has been linked to metabolic diseases. The pancreas-liver-adipose axis is largely affected by cadmium accumulation. Therefore, this review aims to collect bibliographic information that establishes the basis for understanding the molecular and cellular mechanisms linked to cadmium with carbohydrate, lipids, and endocrine impairments that contribute to developing insulin resistance, metabolic syndrome, prediabetes, and diabetes.

Nicotinamide mononucleotide alters body composition and ameliorates metabolic disorders induced by a high-fat diet

Obesity is caused by an imbalance between calorie intake and energy expenditure, leading to excessive adipose tissue accumulation. Nicotinamide adenine dinucleotide (NAD⁺ ) is an important molecule in energy and signal transduction, and NAD⁺ supplementation therapy is a new treatment for obesity in recent years. Liver kinase B1 (LKB1) is an energy metabolism regulator. The relationship between NAD⁺ and LKB1 has only been studied in the heart and has not yet been reported in obesity. Nicotinamide mononucleotide (NMN), as a direct precursor of NAD⁺ , can effectively enhance the level of NAD⁺ . In the current study, we showed that NMN intervention altered body composition in obese mice, characterized by a reduction in fat mass and an increase in lean mass. NMN reversed high-fat diet-induced blood lipid levels then contributed to reducing hepatic steatosis. NMN also improved glucose tolerance and alleviated adipose tissue inflammation. Moreover, our data suggested that NMN supplementation may be depends on the NAD⁺ /SIRT6/LKB1 pathway to regulate brown adipose metabolism. These results provided new evidence for NMN in obesity treatment.

Identification and Validation of Immune-Related Genes Diagnostic for Progression of Atherosclerosis and Diabetes

Background

Atherosclerosis and type 2 diabetes mellitus contribute to a large part of cardiovascular events, but the underlying mechanism remains unclear. In this study, we focused on identifying the linking genes of the diagnostic biomarkers and effective therapeutic targets associated with these two diseases.

Methods

The transcriptomic datasets of atherosclerosis and type 2 diabetes mellitus were obtained from the GEO database. Differentially expressed genes analysis was performed by R studio software, and differential analysis including functional enrichment, therapeutic small molecular agents prediction, and protein-protein interaction analysis were applied to the common shared differentially expressed genes. Hub genes were identified and further validated using an independent dataset and clinical samples. Furthermore, we measured the expression correlations, immune cell infiltration, and diagnostic capability of the three key genes.

Results

We screened out 28 up-regulated and six down-regulated common shared differentially expressed genes. Functional enrichment analysis showed that cytokines and immune activation were involved in the development of these two diseases. Six small molecules with the highest absolute enrichment value were identified. Three critical genes (CD4, PLEK, and THY1) were further validated both in validation sets and clinical samples. The gene correlation analysis showed that CD4 was strongly positively correlated with PLEK, and ROC curves confirmed the good discriminatory capacity of CD4 and PLEK in two diseases.

We have established the co-expression network between atherosclerosis lesions progressions and type 2 diabetes mellitus, and identified CD4 and PLEK as key genes in the two diseases, which may facilitate both development of diagnosis and therapeutic strategies.

Multi-probiotic consumption sex-dependently interferes with MSG-induced obesity and concomitant phagocyte pro-inflammatory polarization in rats: Food for thought about personalized nutrition

Epidemic scope which obesity has reached in many countries necessitates shifting the emphasis in medicine from traditional reaction to individualized and personalized prevention. Numerous trials convincingly prove sexual dimorphism of obesity in morbidity, pathophysiology, comorbidity, outcomes and prophylaxis efficacy. Obesity is characterized by chronic systemic low-grade inflammation that creates the preconditions for the emergence of numerous comorbidities. Leading role in the initiation, propagation and resolution of inflammation belongs to tissue resident and circulating phagocytes. The outcome of inflammation largely depends on phagocyte functional polarization, which in turn is governed by environmental stimuli. Gut microbiota (GM), whose disturbances are one of the key pathogenetic features in obesity, substantially affect phagocyte functions and can either aggravate or calm obesity-associated inflammation. Probiotics possess promising physiological functions, including microbiota-restoring and anti-inflammatory traits, that may possibly help prevent obesity. However, sex-specific effects of probiotic supplementation for targeted obesity prevention remain unknown. The aim of the current study was aimed to compare the effect of multi-probiotic preparation used in prophylactic regimen on the adiposity, profile of culturable GM and its short-chain fatty acids as well as on functional profile of phagocytes from different locations in male and female rats with monosodium glutamate (MSG)-induced obesity. Obesity was induced by neonatal MSG injections in male and female rats, who were given the multi-species probiotic during juvenile and adult developmental stages. Culturable fecal and mucosa-associated microbiota of the intestine were examined using selective diagnostic media. Short-chain fatty acid profile in fecal samples was determined by GC-MS. Phagocyte functional profile was evaluated using flow cytometry and colorimetric methods. Probiotic supplementation after the administration of MSG prevented weight gain and fat accumulation, inflammatory phagocyte activation and alterations in GM in female rats. In male MSG-injected rats, probiotic supplementation restricted but did not prevent weight gain and fat deposition, alleviated but did not prevent systemic inflammation, prevented the alterations in GM, but with residual imbalance in the ratio of obligate anaerobic to facultative anaerobic bacteria. Our findings emphasize the necessity of sex-centered approaches to the prophylactic use of probiotics in obesity in the context of predictive preventive and personalized medicine.

Forkhead box P3 gene polymorphisms predispose to type 2 diabetes and diabetic nephropathy in the Han Chinese populations: a genetic-association and gender-based evaluation study

BACKGROUND

Functional mutations or polymorphisms affecting forkhead box P3 (FOXP3) can lead to their abnormal FOXP3 gene expression and/or defective Treg cells generation, thus resulting in autoimmune disease and inflammatory disorders. FOXP3 also plays a key role in Type 2 diabetes mellitus (T2DM) and its complications, because the disease usually involves chronic low-grade inflammatory disorders and is associated with long-term immune system imbalance. This study aimed to investigate the association between FOXP3 polymorphisms and the susceptibility to T2DM and type 2 diabetes nephropathy (T2DN) within the Han Chinese populations.

METHODS

Polymorphisms in rs3761548C/A and rs2294021C/T were examined in 400 patients (which include an equal number of T2DM and T2DN groups) and 200 healthy controls using PCR-HRM and sequence analysis.

RESULTS

The genotype and allelic frequencies of the two single nucleotide polymorphisms (SNPs) were significantly different in T2DM and the progression of diabetes developing to T2DN. The further gender-based evaluation showed that in female subjects, rs3761548C/A was associated with an approximately 3-fold higher threat for T2DM and 4.5-fold for T2DN, while there was no noticeable association with rs2294021C/T; in males, the promoter polymorphism showed an increased predisposition of 5.4-fold and 3.4-fold predisposition to T2DM and T2DN, respectively, while rs2294021 polymorphism could impart a nearly 2-fold risk of developing T2DN. An additional analysis of combined genotypes (rs3761548 C/A-rs2294021C/T) revealed that CC-CC and CC-CT can be considered protective combinations in the predisposition of males with diabetes towards T2DN, while AA-CC and AA-TT have the opposite effect.

CONCLUSIONS

This study demonstrated the possible involvement of individual and combined genetic associations of rs3761548C/A and rs2294021C/T polymorphisms with the susceptibility to diabetes and diabetic nephropathy in the Han Chinese population, as well as gender bias.

Associations between Systemic Immune-Inflammation Index and Diabetes Mellitus Secondary to Pancreatic Ductal Adenocarcinoma

BACKGROUND

There is a high prevalence of diabetes mellitus (DM) in patients with pancreatic ductal adenocarcinoma (PDAC). An inflammatory response is considered as a potential mechanism involved in the process. The systemic immune-inflammation (SII) index is an integrated and novel inflammatory indicator developed in recent years. The purpose of this study was to determine the relationship between the SII and DM secondary to PDAC.

METHOD

Patients with a confirmed diagnosis of PDAC were analyzed in this cross-sectional study. Anthropometric measures, glucose-related data (including fasting glucose, 2 h OGTT, glycated hemoglobin, fasting insulin, and fasting c-peptide), tumor characteristics (tumor volumes, location and stages), and the periphery blood inflammatory index (white blood cell count, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and SII) were recorded. The inflammation index was analyzed for its association with glucose-related parameters. Multivariable logistic regression analysis was used to analyze the association between SII levels and DM secondary to PDAC.

RESULTS

Blood cell results showed that the white blood cell count, neutrophils, lymphocytes, monocytes, platelets, the neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio were higher in patients with diabetes. It was worth noting that SII significantly increased in patients with diabetes secondary to PDAC (4.41 vs. 3.19, p < 0.0001). Multivariable logistic regression analysis showed that SII (OR: 2.024, 95%CI: 1.297, 3.157, p = 0.002) and age (OR: 1.043, 95%CI: 1.01, 1.077, p = 0.011) were the risk factors for DM secondary to PDAC after adjusting for covariates. According to Spearmen correlation analysis, SII was positively correlated with fasting glucose (r = 0.345, p < 0.0001), 2 h OGTT (r = 0.383, p < 0.0001), HbA1c (r = 0.211, p = 0.005), fasting insulin (r = 0.435, p < 0.0001), fasting C-peptide (r = 0.420, p < 0.0001), and HOMA2-IR (r = 0.491, p < 0.0001).

CONCLUSIONS

In conclusion, SII is significantly increased among patients with DM secondary to PDAC and is associated with the DM in patients with PDAC (OR: 2.382, 95% CI: 1.157, 4.903, p = 0.019). Additionally, SII is significantly correlated with insulin resistance. We are the first to investigate the relationship between SII and diabetes secondary to PDAC and further confirm the role of an inflammatory response in this process. More studies need to be designed to clarify how inflammatory responses participate.

RNA-Seq analysis of obese Pdha1fl/flLyz2-Cre mice induced by a high-fat diet

Pyruvate dehydrogenase complex (PDH) is an important complex of three enzymes that transforms pyruvate into acetyl-CoA, subsequently entering the tricarboxylic acid (TCA) cycle to produce ATP and electron donors. As a key regulator of energy and metabolic homeostasis, PDH is considered a potential therapeutic target of many diseases. On the other hand, the relationship between PDH and obesity is not clear. In this study, peripheral blood of Pdha1^fl/flLyz2-Cre and C57BL/6 mice fed a high-fat diet (HFD) was collected and subjected to extensive transcriptome sequencing. Differentially expressed genes (DEGs) were identified. Enrichment of functions and signaling pathways analyses were performed based on Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to verify the genes selected from RNA sequencing (RNA-seq). Eventually, we found that Pdha1^fl/flLyz2-Cre mice were more susceptible to HFD-induced obesity. A total of 302 up-regulated genes and 30 down-regulated genes were screened that were differentially expressed between Pdha1^fl/flLyz2-Cre mice fed the HFD and the control groups. Furthermore, we verified that significant transcriptional changes in the genes Sgstm1, Ncoa4, Rraga, Slc3a2, Usp15, Gabarapl2, Wipi1, Sh3glb1, Mtmr3, and Cd36 were consistent with the results obtained from RNA-seq analysis. In summary, this study preliminarily established that there is a close relationship between Pdha1 and obesity and revealed the possible downstream pathways and target genes involved, laying a good foundation for the further study of Pdha1 function in the future.

Adolescents with Type 2 Diabetes: Overcoming Barriers to Effective Weight Management

The prevalence of type 2 diabetes (T2DM) among children and adolescents has remarkably increased in the last two decades, particularly among ethnic minorities. Management of T2DM is challenging in the adolescent population due to a constellation of factors, including biological, socioeconomic, cultural, and psychological barriers. Weight reduction is an essential component in management of T2DM as weight loss is associated with improvement in insulin sensitivity and glycemic status. A family centered and culturally appropriate approach offered by a multidisciplinary team is crucial to address the biological, psychosocial, cultural, and financial barriers to weight management in youth with T2DM. Lifestyle interventions and pharmacotherapy have shown modest efficacy in achieving weight reduction in adolescents with T2DM. Bariatric surgery is associated with excellent weight reduction and remission of T2DM in youth. Emerging therapies for weight reduction in youth include digital technologies, newer GLP-1 agonists and endoscopic procedures.

The Molecular Basis of the Anti-Inflammatory Property of Astragaloside IV for the Treatment of Diabetes and Its Complications

Astragali Radix is a significant traditional Chinese medication, and has a long history of clinical application in the treatment of diabetes mellitus (DM) and its complications. AS-IV is an active saponin isolated from it. Modern pharmacological study shows that AS-IV has anti-inflammatory, anti-oxidant and immunomodulatory activities. The popular inflammatory etiology of diabetes suggests that DM is a natural immune and low-grade inflammatory disease. Pharmacological intervention of the inflammatory response may provide promising and alternative approaches for the prevention and treatment of DM and its complications. Therefore, this article focuses on the potential of AS-IV in the treatment of DM from the perspective of an anti-inflammatory molecular basis. AS-IV plays a role by regulating a variety of anti-inflammatory pathways in multiple organs, tissues and target cells throughout the body. The blockade of the NF-κB inflammatory signaling pathway may be the central link of AS-IV's anti-inflammatory effect, resulting in a reduction in the tissue structure and function damage stimulated by inflammatory factors. In addition, AS-IV can delay the onset of DM and its complications by inhibiting inflammation-related oxidative stress, fibrosis and apoptosis signals. In conclusion, AS-IV has therapeutic prospects from the perspective of reducing the inflammation of DM and its complications. An in-depth study on the anti-inflammatory mechanism of AS-IV is of great significance for the effective use of Chinese herbal medicine and the promotion of its status and influence on the world.

Bariatric Surgery: Targeting pancreatic β cells to treat type II diabetes

Pancreatic β-cell function impairment and insulin resistance are central to the development of obesity-related type 2 diabetes mellitus (T2DM). Bariatric surgery (BS) is a practical treatment approach to treat morbid obesity and achieve lasting T2DM remission. Traditionally, sustained postoperative glycemic control was considered a direct result of decreased nutrient intake and weight loss. However, mounting evidence in recent years implicated a weight-independent mechanism that involves pancreatic islet reconstruction and improved β-cell function. In this article, we summarize the role of β-cell in the pathogenesis of T2DM, review recent research progress focusing on the impact of Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) on pancreatic β-cell pathophysiology, and finally discuss therapeutics that have the potential to assist in the treatment effect of surgery and prevent T2D relapse.

Role of Macrophage in Type 2 Diabetes Mellitus: Macrophage Polarization a New Paradigm for Treatment of Type 2 Diabetes Mellitus

Metabolic diseases such as type 2 diabetes mellitus are usually associated with meta-inflammation. β-cell failure is a marked feature observed in the pathogenesis of type 2 diabetes mellitus. Type 2 diabetes mellitus (T2DM) is a heterogeneous situation that is accompanied by not only defective insulin secretion but also peripheral insulin resistance. β-cells are the primary organ for insulin secretion; hence, it is crucial to maintain a significant β-cell mass in response to a variety of changes. Insulin resistance is a chief cause of T2DM, leading to increased free fatty acid (FFA) levels, which in turn elevates β-cell mass and insulin secretion as compensation for insulin insensitivity. It has recently been established that amplified numbers of innate immune cells, cytokines, and chemokines result in detrimental effects on islets in chronic conditions. Macrophage migration inhibitory factor (MIF) is the lymphokine that prevents arbitrary migration of macrophages and assembles macrophages at inflammatory loci. Inflammation is known to trigger monocytes to differentiate into macrophages. Progress of complications associated with type 2 diabetes mellitus, as indicated through recent findings, is also dependent on the buildup of macrophages in tissues vulnerable to diabetic injury. The present article scientifically evaluates the present knowledge concerning the mechanisms of monocyte and macrophage-mediated injury recruitment in complications associated with type 2 diabetes mellitus. It also describes some of the established and experimental therapies that might bring about a reduction in these inflammatory complications. Recent discoveries in the field of drug delivery have facilitated phenotype-specific targeting of macrophages. This review highlights the pathophysiology of type 2 diabetes mellitus, how macrophage induces type 2 diabetes mellitus and potential therapeutics for type 2 diabetes mellitus via macrophage-specific delivery.

Establishment and validation of a predictive nomogram for gestational diabetes mellitus during early pregnancy term: A retrospective study

OBJECTIVE

This study aims to develop and evaluate a predictive nomogram for early assessment risk factors of gestational diabetes mellitus (GDM) during early pregnancy term, so as to help early clinical management and intervention.

METHODS

A total of 824 pregnant women at Zhongnan Hospital of Wuhan University and Maternal and Child Health Hospital of Hubei Province from 1 February 2020 to 30 April 2020 were enrolled in a retrospective observational study and comprised the training dataset. Routine clinical and laboratory information was collected; we applied least absolute shrinkage and selection operator (LASSO) logistic regression and multivariate ROC risk analysis to determine significant predictors and establish the nomogram, and the early pregnancy files (gestational weeks 12-16, n = 392) at the same hospital were collected as a validation dataset. We evaluated the nomogram via the receiver operating characteristic (ROC) curve, C-index, calibration curve, and decision curve analysis (DCA).

RESULTS

We conducted LASSO analysis and multivariate regression to establish a GDM nomogram during the early pregnancy term; the five selected risk predictors are as follows: age, blood urea nitrogen (BUN), fibrinogen-to-albumin ratio (FAR), blood urea nitrogen-to-creatinine ratio (BUN/Cr), and blood urea nitrogen-to-albumin ratio (BUN/ALB). The calibration curve and DCA present optimal predictive power. DCA demonstrates that the nomogram could be applied clinically.

CONCLUSION

An effective nomogram that predicts GDM should be established in order to help clinical management and intervention at the early gestational stage.

Effects of High-Fat Diet on Cardiovascular Protein Expression in Mice Based on Proteomics

PURPOSE

To investigate the effect of high-fat diet on protein expression in mouse heart and aorta using proteomic techniques.

METHODS

A high-fat diet was used to construct an obese mouse model, and body weight was checked regularly. After the experiment, serum lipid and oxidative stress levels were measured. Proteomic detection of cardiac and aortic protein expression. Cardiac and aortic common differentially expressed proteins (Co-DEPs) were screened based on proteomic results. Subsequently, functional enrichment analysis and screening of key proteins were performed.

RESULTS

A high-fat diet significantly increased body weight in mice. Obese mice had considerably higher levels of TC, TG, LDL-C, ROS, and MDA. In the heart and aorta, 17 Co-DEPs were discovered. The results of functional analysis of these proteins indicated that they were mainly related to lipid metabolism. Ech1, Decr1, Hsd17b4, Hsdl2 and Acadvl were screened as key proteins. In mice, a high-fat diet causes lipid metabolism to become disrupted, resulting in higher levels of oxidative stress and lipid peroxidation products.

CONCLUSION

Ech1, Decr1, Hsd17b4, Hsdl2 and Acadvl as cardiac and aortic Co-DEPs are closely related to lipid metabolism and may serve as potential diagnostic and therapeutic targets for obesity-induced cardiovascular disease.

Rebamipide treatment ameliorates obesity phenotype by regulation of immune cells and adipocytes

Obesity is a medical term used to describe an over-accumulation of adipose tissue. It causes abnormal physiological and pathological processes in the body. Obesity is associated with systemic inflammation and abnormalities in immune cell function. Rebamipide, an amino acid derivative of 2-(1H)-quinolinone, has been used as a therapeutic for the protection from mucosal damage. Our previous studies have demonstrated that rebamipide treatment regulates lipid metabolism and inflammation, leading to prevention of weight gain in high-fat diet mice. In this study, mice were put on a high calorie diet for 11 weeks while receiving injections of rebamipide. Rebamipide treatment reduced the body weight, liver weight and blood glucose levels compared to control mice and reduced both glucose and insulin resistance. Fat accumulation has been shown to cause pro-inflammatory activity in mice. Treatment with rebamipide decreased the prevalence of inflammatory cells such as Th2, Th17 and M1 macrophages and increased anti-inflammatory Treg and M2 macrophages in epididymal fat tissue. Additionally, rebamipide addition inhibited adipocyte differentiation in 3T3-L1 cell lines. Taken together, our study demonstrates that rebamipide treatment is a novel and effective method to prevent diet-induced obesity.

RNA binding protein HuD mediates the crosstalk between β cells and islet endothelial cells by the regulation of Endostatin and Serpin E1 expression

RNA binding protein HuD plays essential roles in gene expression by regulating RNA metabolism, and its dysregulation is involved in the pathogenesis of several diseases, including tumors, neurodegenerative diseases, and diabetes. Here, we explored HuD-mediated differential expression of secretory proteins in mouse insulinoma βTC6 cells using a cytokine array. Endostatin and Serpin E1 that play anti-angiogenic roles were identified as differentially expressed proteins by HuD. HuD knockdown increased the expression of α chain of collagen XVIII (Col18a1), a precursor form of endostatin, and Serpin E1 by associating with the 3'-untranslated regions (UTRs) of Col18a1 and Serpin E1 mRNAs. Reporter analysis revealed that HuD knockdown increased the translation of EGFP reporters containing 3'UTRs of Col18a1 and Serpin E1 mRNAs, which suggests the role of HuD as a translational repressor. Co-cultures of βTC6 cells and pancreatic islet endothelial MS1 cells were used to assess the crosstalk between β cells and islet endothelial cells, and the results showed that HuD downregulation in βTC6 cells inhibited the growth and migration of MS1 cells. Ectopic expression of HuD decreased Col18a1 and Serpin E1 expression, while increasing the markers of islet vascular cells in the pancreas of db/db mice. Taken together, these results suggest that HuD has the potential to regulate the crosstalk between β cells and islet endothelial cells by regulating Endostatin and Serpin E1 expression, thereby contributing to the maintenance of homeostasis in the islet microenvironment.

Exenatide regulates Th17/Treg balance via PI3K/Akt/FoxO1 pathway in db/db mice

BACKGROUND

The T helper 17 (Th17)/T regulatory (Treg) cell imbalance is involved in the course of obesity and type 2 diabetes mellitus (T2DM). In the current study, the exact role of glucagon-like peptide-1 receptor agonist (GLP-1RA) exenatide on regulating the Th17/Treg balance and the underlying molecular mechanisms are investigated in obese diabetic mice model.

METHODS

Metabolic parameters were monitored in db/db mice treated with/without exenatide during 8-week study period. The frequencies of Th17 and Treg cells from peripheral blood and pancreas in db/db mice were assessed. The phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/Forkhead box O1 (FoxO1) pathway in Th17 and Treg cells from the spleens of male C57BL/6J mice was detected by western blotting. In addition, the expression of glucagon-like peptide-1 receptor (GLP-1R) in peripheral blood mononuclear cells (PBMCs) of male C57BL/6J mice was analyzed.

RESULTS

Exenatide treatment improved β-cell function and insulitis in addition to glucose, insulin sensitivity and weight. Increased Th17 and decreased Treg cells in peripheral blood were present as diabetes progressed while exenatide corrected this imbalance. Progressive IL-17 + T cell infiltration of pancreatic islets was alleviated by exenatide intervention. In vitro study showed no significant difference in the level of GLP-1R expression in PBMCs between control and palmitate (PA) groups. In addition, PA could promote Th17 but suppress Treg differentiation along with down-regulating the phosphorylation of PI3K/Akt/FoxO1, which was reversed by exenatide intervention. FoxO1 inhibitor AS1842856 could abrogate all these effects of exenatide against lipid stress.

CONCLUSIONS

Exenatide could restore systemic Th17/Treg balance via regulating FoxO1 pathway with the progression of diabetes in db/db mice. The protection of pancreatic β-cell function may be partially mediated by inhibiting Th17 cell infiltration into pancreatic islets, and the resultant alleviation of islet inflammation.

TonEBP in Myeloid Cells Promotes Obesity-Induced Insulin Resistance and Inflammation Through Adipose Tissue Remodeling

The phenotypic and functional plasticity of adipose tissue macrophages (ATMs) during obesity plays a crucial role in orchestration of adipose and systemic inflammation. Tonicity-responsive enhancer binding protein (TonEBP) (also called NFAT5) is a stress protein that mediates cellular responses to a range of metabolic insults. Here, we show that myeloid cell-specific TonEBP depletion reduced inflammation and insulin resistance in mice with high-fat diet-induced obesity but did not affect adiposity. This phenotype was associated with a reduced accumulation and a reduced proinflammatory phenotype of metabolically activated macrophages, decreased expression of inflammatory factors related to insulin resistance, and enhanced insulin sensitivity. TonEBP expression was elevated in the ATMs of obese mice, and Sp1 was identified as a central regulator of TonEBP induction. TonEBP depletion in macrophages decreased induction of insulin resistance-related genes and promoted induction of insulin sensitivity-related genes under obesity-mimicking conditions and thereby improved insulin signaling and glucose uptake in adipocytes. mRNA expression of TonEBP in peripheral blood mononuclear cells was positively correlated with blood glucose levels in mice and humans. These findings suggest that TonEBP in macrophages promotes obesity-associated systemic insulin resistance and inflammation, and downregulation of TonEBP may induce a healthy metabolic state during obesity.

Integrative analyses of hub genes and their association with immune infiltration in adipose tissue, liver tissue and skeletal muscle of obese patients after bariatric surgery

Bariatric surgery (BS) is an effective treatment for obesity. Adipose tissue, liver tissue and skeletal muscle are important metabolic tissues. This study investigated hub genes and their association with immune infiltration in these metabolic tissues of obese patients after BS by bioinformatic analysis with Gene Expression Omnibus datasets. Differentially expressed genes (DEGs) were identified, and a protein–protein interaction network was constructed to identify hub genes. As a result, 121 common DEGs were identified and mainly enriched in cytokine–cytokine receptor interactions, chemokine signaling pathway, neutrophil activation and immune responses. Immune cell infiltration analysis showed that the abundance of M1 macrophages was significantly lower in adipose and liver tissue after BS (p<0.05). Ten hub genes (TYROBP, TLR8, FGR, NCF2, HCK, CCL2, LAPTM5, MNDA and S100A9) that were all downregulated after BS were also associated with immune cells. Consistently, results in the validated dataset showed that the expression levels of these hub genes were increased in obese patients and mice, and decreased after BS. In conclusion, this study analysed the potential immune and inflammatory mechanisms of BS in three key metabolic tissues of obese patients, and revealed hub genes associated with immune cell infiltration, thus providing potential targets for obesity treatment.

Critical Role for Macrophages in the Developmental Programming of Pancreatic β-Cell Area in Offspring of Hypertensive Pregnancies

Preeclampsia is a pregnancy-specific complication with long-term negative outcomes for offspring, including increased susceptibility to type 2 diabetes (T2D) in adulthood. In a rat reduced uteroplacental perfusion pressure (RUPP) model of chronic placental ischemia, maternal hypertension in conjunction with intrauterine growth restriction mimicked aspects of preeclampsia and resulted in female embryonic day 19 (e19) offspring with reduced β-cell area and increased β-cell apoptosis compared with offspring of sham pregnancies. Decreased pancreatic β-cell area persisted to postnatal day 13 (PD13) in females and could influence whether T2D developed in adulthood. Macrophage changes also occurred in islets in T2D. Therefore, we hypothesized that macrophages are crucial to reduction in pancreatic β-cell area in female offspring after chronic placental ischemia. Macrophage marker CD68 mRNA expression was significantly elevated in e19 and PD13 islets isolated from female RUPP offspring compared with sham. Postnatal injections of clodronate liposomes into female RUPP and sham offspring on PD2 and PD9 significantly depleted macrophages compared with injections of control liposomes. Depletion of macrophages rescued reduced β-cell area and increased β-cell proliferation and size in RUPP offspring. Our studies suggest that the presence of macrophages is important for reduced β-cell area in female RUPP offspring and changes in macrophages could contribute to development of T2D in adulthood.

Lipid Peroxidation Linking Diabetes and Cancer: The Importance of 4-Hydroxynonenal

Significance: It is commonly believed that diabetes mellitus may be associated with cancer. Hence, diabetic patients are at higher risk for hepatocellular carcinoma, pancreatic cancer, colorectal cancer, and breast cancer, but the mechanisms that may link these two severe diseases are not well understood. Recent Advances: A number of factors have been suggested to promote tumorigenesis in diabetic patients, including insulin resistance, hyperglycemia, dyslipidemia, inflammation, and elevated insulin-like growth factor-1 (IGF-1), which may also promote pro-oxidants, and thereby alter redox homeostasis. The consequent oxidative stress associated with lipid peroxidation appears to be a possible pathogenic link between cancer and diabetes. Critical Issues: Having summarized the above aspects of diabetes and cancer pathology, we propose that the major bioactive product of oxidative degradation of polyunsaturated fatty acids (PUFAs), the reactive aldehyde 4-hydroxynonenal (4-HNE), which is also considered a second messenger of free radicals, may be the key pathogenic factor linking diabetes and cancer. Future Directions: Because the bioactivities of 4-HNE are cell-type and concentration-dependent, are often associated with inflammation, and are involved in signaling processes that regulate antioxidant activities, proliferation, differentiation, and apoptosis, we believe that further research in this direction could reveal options for better control of diabetes and cancer. Controlling the production of 4-HNE to avoid its cytotoxicity to normal but not cancer cells while preventing its diabetogenic activities could be an important aspect of modern integrative biomedicine. Antioxid. Redox Signal. 37, 1222-1233.