NF-κB-Inducing Kinase Provokes Insulin Resistance in Skeletal Muscle of Obese Mice

Body Roundness Index Trajectories and the Risk of Cancer: A Cohort Study

BACKGROUND

The body rounds index (BRI), an innovative obesity indicator integrating waist circumference (WC) and height, offers a two-dimensional assessment of obesity. The relationship between BRI trajectories and cancer has been overlooked in previous studies. This study aims to explore the association between BRI trajectories and the incidence of cancer.

METHODS

This study included 42,022 participants with a median age of 48.91 years. Based on the changes in participants' BRI during the period from 2006 to 2010, three BRI trajectory patterns were identified: low-stable, medium-stable, and high-stable. The primary outcome was cancer incidence and the secondary outcome was cancer-specific deaths. The association between BRI trajectories and cancer incidence and death was explored by cox regression analysis in the total, sex-specific and age-specific populations, respectively. Additionally, we further investigated the relationship between BRI and site-specific cancer incidence. Sensitivity analyses were applied to exclude interferences and ensure the stability of the results.

RESULTS

After a median follow-up time of 11.04 years, high-stable BRI trajectory was significantly associated with increased risk of cancer occurrence compared to low-stable BRI trajectory. This association was more pronounced in middle-aged men (men: HR = 1.46, 95% CI = 1.21-1.77, p < 0.001; age < 65: HR = 11.38, 95% CI = 1.15-1.66, p = 0.001). Additionally, high-stable BRI trajectory was significantly associated with a substantial increase in the risk of site-specific uterine cancers (HR = 4.92, 95% CI = 1.69-14.33, p = 0.004). Sensitivity analysis confirmed the stability of the results.

CONCLUSION

Our study identified a significant association between a high-stable BRI trajectory and cancer incidence, with this association being most pronounced in middle-aged men. Moreover, the high-stable BRI trajectory was strongly associated with uterine site-specific cancer development. Our findings underscore the importance of implementing lifestyle modifications and monitoring BRI values and their changes to provide effective health guidance.

NIK Is a Mediator of Inflammation and Intimal Hyperplasia in Endothelial Denudation-Induced Vascular Injury

Neointimal hyperplasia is the main cause of vascular graft failure in the medium term. NFκB is a key mediator of inflammation that is activated during neointimal hyperplasia following endothelial injury. However, the molecular mechanisms involved in NFκB activation are poorly understood. NFκB may be activated through canonical (transient) and non-canonical (persistent) pathways. NFκB-inducing kinase (NIK, MAP3K14) is the upstream kinase of the non-canonical pathway. We have now explored the impact of NIK deficiency on neointimal hyperplasia following guidewire-induced endothelial cell injury and on local inflammation by comparing NIK activity-deficient alymphoplasia mice (NIKaly/aly) with control wild-type (NIK+/+) mice. Guidewire-induced endothelial cell injury caused neointimal hyperplasia and luminal stenosis and upregulated the local expression of NIK and the NFκB target chemokines monocyte chemoattractant protein-1 (MCP-1/CCL2) and chemokine ligand 5 (RANTES/CCL5). Immunohistochemistry disclosed the infiltration of the media and intima by F4/80 positive macrophages. The intima/media ratio and percentage of stenosis were milder in the NIKaly/aly than in the NIK+/+ mice. Additionally, the gene expression for MCP-1 and RANTES was lower and F4/80+ cell infiltration was milder in the NIKaly/aly than in the NIK+/+ mice. Finally, circulating MCP-1 levels were lower in the NIKaly/aly than in the NIK+/+ mice, reflecting milder systemic inflammation. In conclusion, NIK is a driver of vascular wall inflammation and stenosis following guidewire-induced endothelial cell injury. NIK targeting may be a novel therapeutic approach to limit arterial stenosis following endothelial cell injury.

EDA2R-NIK signaling in cancer cachexia

PURPOSE OF REVIEW

Cachexia is a debilitating condition causing weight loss and skeletal muscle wasting that negatively influences treatment and survival of cancer patients. The objective of this review is to describe recent discoveries on the role of a novel signaling pathway involving ectodysplasin A2 receptor (EDA2R) and nuclear factor κB (NFκB)-inducing kinase (NIK) in muscle atrophy.

RECENT FINDINGS

Studies identified tumor-induced upregulation of EDA2R expression in muscle tissues in pre-clinical cachexia models and patients with various cancers. Activation of EDA2R by its ligand promoted atrophy in cultured myotubes and muscle tissue, which depended on NIK activity. The non-canonical NFκB pathway via NIK also stimulated muscle atrophy. Mice lacking EDA2R or NIK were protected from muscle loss due to tumors. Tumor-induced cytokine oncostatin M (OSM) upregulated EDA2R expression in muscles whereas OSM receptor-deficient mice were resistant to muscle wasting.

SUMMARY

Recent discoveries revealed a mechanism involving EDA2R-NIK signaling and OSM that drives cancer-associated muscle loss, opening up new directions for designing anti-cachexia treatments. The therapeutic potential of targeting this mechanism to prevent muscle loss should be further investigated. Future research should also explore broader implications of the EDA2R-NIK pathway in other muscle wasting diseases and overall muscle health.

The Potential of Anti-Inflammatory DC Immunotherapy in Improving Proteinuria in Type 2 Diabetes Mellitus

A typical consequence of type 2 diabetes mellitus, diabetic kidney disease (DKD) is a significant risk factor for end-stage renal disease. The pathophysiology of diabetic kidney disease (DKD) is mainly associated with the immune system, which involves adhesion molecules and growth factors disruption, excessive expression of inflammatory mediators, decreased levels of anti-inflammatory mediators, and immune cell infiltration in the kidney. Dendritic cells are professional antigen-presenting cells acting as a bridge connecting innate and adaptive immune responses. The anti-inflammatory subset of DCs is also capable of modulating inflammation. Autologous anti-inflammatory dendritic cells can be made by in vitro differentiation of peripheral blood monocytes and utilized as a cell-based therapy. Treatment with anti-inflammatory cytokines, immunosuppressants, and substances derived from pathogens can induce tolerogenic or anti-inflammatory features in ex vivo-generated DCs. It has been established that targeting inflammation can alleviate the progression of DKD. Recent studies have focused on the potential of dendritic cell-based therapies to modulate immune responses favorably. By inducing a tolerogenic phenotype in dendritic cells, it is possible to decrease the inflammatory response and subsequent kidney damage. This article highlights the possibility of using anti-inflammatory DCs as a cell-based therapy for DKD through its role in controlling inflammation.

Transcriptome sequencing and bioinformatics analysis of gastrocnemius muscle in type 2 diabetes mellitus rats

OBJECTIVE

Type 2 diabetes mellitus (T2DM) is one of the high risk factors for sarcopenia. However, the pathogenesis of diabetic sarcopenia has not been fully elucidated. This study obtained transcriptome profiles of gastrocnemius muscle in normal and T2DM rats based on high-throughput sequencing technology, which may provide new ideas for exploring the pathogenesis of diabetic sarcopenia.

METHODS

Twelve adult male Sprague-Dawley rats were randomly divided into Control group and T2DM group, and gastrocnemius muscle tissue was retained for transcriptome sequencing and real-time quantitative polymerase chain reaction (qRT-PCR) 6 months later. Screening differentially expressed genes (DEGs), Cluster analysis, gene ontology (GO) functional annotation analysis and Kyoto Encyclopedia of Genes and Gnomes (KEGG) functional annotation and enrichment analysis were performed for DEGs. Six DEGs related to apoptosis were selected for qTR-PCR verification.

RESULTS

Transcriptomic analysis showed that there were 1016 DEGs between the gastrocnemius muscle of T2DM and normal rats, among which 665 DEGs were up-regulated and 351 DEGs were down-regulated. GO analysis showed that the extracellular matrix organization was the most enriched in biological processes, with 26 DEGs. The extracellular matrix with 35 DEGs was the most abundant cellular component. The extracellular matrix structural constituent, with 26 DEGs, was the most enriched in molecular functions. The highest number of DEGs enriched in biological processes, cellular components and molecular functions were positive regulation of transcription by RNA polymerase II, nucleus and metal ion binding, respectively. There were 78, 230 and 89 DEGs respectively. KEGG pathway enrichment analysis showed that ECM-receptor interaction, PI3K-Akt signaling pathway and TGF-β signaling pathway(p < 0.001) had higher enrichment degree and number of DEGs. qRT-PCR results showed that the fold change of Map3k14, Atf4, Pik3r1, Il3ra, Gadd45b and Bid were 1.95, 3.25, 2.97, 2.38, 0.43 and 3.6, respectively. The fold change of transcriptome sequencing were 3.45, 2.21, 2.59, 5.39, 0.49 and 2.78, respectively. The transcriptional trends obtained by qRT-PCR were consistent with those obtained by transcriptome sequencing.

CONCLUSIONS

Transcriptomic analysis was used to obtain the "gene profiles" of gastrocnemius muscle of T2DM and normal rats. qRT-PCR verification showed that the genes related to apoptosis were differentially expressed. These DEGs and enrichment pathways may provide new ideas for exploring the pathogenesis of diabetic sarcopenia.

Ectodysplasin A2 receptor signaling in skeletal muscle pathophysiology

Skeletal muscle is essential in generating mechanical force and regulating energy metabolism and body temperature. Pathologies associated with muscle tissue often lead to impaired physical activity and imbalanced metabolism. Recently, ectodysplasin A2 receptor (EDA2R) signaling has been shown to promote muscle loss and glucose intolerance. Upregulated EDA2R expression in muscle tissue was associated with aging, denervation, cancer cachexia, and muscular dystrophies. Here, we describe the roles of EDA2R signaling in muscle pathophysiology, including muscle atrophy, insulin resistance, and aging-related sarcopenia. We also discuss the EDA2R pathway, which involves EDA-A2 as the ligand and nuclear factor (NF)κB-inducing kinase (NIK) as a downstream mediator, and the therapeutic potential of targeting these proteins in the treatment of muscle wasting and metabolic dysfunction.

Mitigation of chronic glucotoxicity-mediated skeletal muscle atrophy by arachidonic acid

Toxicity caused by chronic hyperglycemia is a significant factor affecting skeletal muscle myogenesis, resulting in diabetic myopathy. Chronic and persistent hyperglycemia causes activation of the atrophy-related pathways in the skeletal muscles, which eventually results in inflammation and muscle degeneration. To counteract this process, various bioactive compound has been studied for their reversal or hypertrophic effect. In this study, we explored the molecular mechanisms associated with reversing glucotoxicity's effect in C2C12 cells by arachidonic acid (AA). We found a substantial increase in the pro-inflammatory cytokines and ROS production in hyperglycemic conditions, mitigated by AA supplementation. We found that AA supplementation restored protein synthesis that was downregulated under glucotoxicity conditions. AA enhanced myogenesis by suppressing high glucose induced inflammation and ROS production and enhancing protein synthesis. These results imply that AA has cytoprotective actions against hyperglycemia-induced cytotoxicity.

Muscle wasting: emerging pathways and potential drug targets

Muscle wasting is a serious comorbidity associated with many disorders, including cancer, kidney disease, heart failure, and aging. Progressive loss of skeletal muscle mass negatively influences prognosis and survival, and is often accompanied by frailty and poor quality of life. Clinical trials testing therapeutics against muscle wasting have yielded limited success. Some therapies improved muscle mass in patients without appreciable differences in physical performance. This review article discusses emerging pathways that regulate muscle atrophy, including oncostatin M (OSM) and ectodysplasin A2 (EDA2) receptor (EDA2R) signaling, outcomes of recent clinical trials, and potential drug targets for future therapies.