Transcription factor 21 (TCF21) promotes proinflammatory interleukin 6 expression and extracellular matrix remodeling in visceral adipose stem cells

Single-cell multiomic analysis identifies macrophage subpopulations in promoting cardiac repair

Cardiac mononuclear phagocytic cells (Cardiac MPCs) participate in maintaining homeostasis and orchestrating cardiac responses upon injury. However, the function of specific MPC subtypes and the related cell fate commitment mechanisms remain elusive in regenerative and nonregenerative hearts due to their cellular heterogeneities. Using spatiotemporal single-cell epigenomic analysis of cardiac MPCs in regenerative (P1) and nonregenerative (P10) mouse hearts after injury, we found that P1 hearts accumulate reparative Arg1+ macrophages, while proinflammatory S100a9+Ly6c+ monocytes are uniquely abundant during nonregenerative remodeling. Moreover, blocking chemokine CXCR2 to inhibit the specification of the S100a9+Ly6c+-biased inflammatory fate in P10 hearts resulted in elevated wound repair responses and marked improvements in cardiac function after injury. Single-cell RNA-Seq further confirmed an increased Arg1+ macrophage subpopulation after CXCR2 blockade, which was accomplished by increased expression of wound repair-related genes and reduced expression of proinflammatory genes. Collectively, our findings provide instructive insights into the molecular mechanisms underlying the function and fate specification of heterogeneous MPCs during cardiac repair and identify potential therapeutic targets for myocardial infarction.

Polymorphism rs2327430 in TCF21 predicts the risk and prognosis of gastric cancer by affecting the binding between TFAP2A and TCF21

BACKGROUND

Single nuclear polymorphisms (SNPs) have been published to be correlated with multiple diseases. Transcription Factor 21 (TCF21) is a critical transcription factor involved in various types of cancers. However, the association of TCF21 genetic polymorphisms with gastric cancer (GC) susceptibility and prognosis remains unclear.

METHODS

A case-control study comprising 890 patients diagnosed with GC and an equal number of cancer-free controls was conducted. After rigorous statistical analysis, molecular experiments were carried out to elucidate the functional significance of the SNPs in the context of GC.

RESULTS

TCF21 rs2327430 (OR = 0.78, P = 0.026) provides protection against GC, while rs4896011 (OR = 1.39, P = 0.005) exhibit significant associations with GC risk. Furthermore, patients with the (TC + CC) genotype of rs2327430 demonstrate a relatively favorable prognosis (OR = 0.47, P = 0.012). Mechanistically, chromatin immunoprecipitation assay and luciferase reporter assay revealed that the C allele of rs2327430 disrupts the binding of Transcription Factor AP-2 Alpha (TFAP2A) to the promoter region of TCF21, resulting in increased expression of TCF21 and inhibition of malignant behaviors in GC cells.

CONCLUSION

Our findings highlight the significant role of TCF21 SNPs in both the risk and prognosis of GC and provide valuable insights into the underlying molecular mechanisms. Specifically, the disruptive effect of rs2327430 on TCF21 expression and its ability to modulate malignant cell behaviors suggest that rs2327430 may serve as a potential predictive marker for GC risk and prognosis.

Transcription Factor 21: A Transcription Factor That Plays an Important Role in Cardiovascular Disease

BACKGROUND

According to the World Health Organisation's Health Report 2019, approximately 17.18 million people die from cardiovascular disease each year, accounting for more than 30% of all global deaths. Therefore, the occurrence of cardiovascular disease is still a global concern. The transcription factor 21 (TCF21) plays an important role in cardiovascular diseases. This article reviews the regulation mechanism of TCF21 expression and activity and focuses on its important role in atherosclerosis in order to contribute to the development of diagnosis and treatment of cardiovascular diseases.

SUMMARY

TCF21 is involved in the phenotypic regulation of vascular smooth muscle cells (VSMCs), promotes the proliferation and migration of VSMCs, and participates in the activation of inflammatory sequences. Increased proliferation and migration of VSMCs can lead to neointimal hyperplasia after vascular injury. Abnormal hyperplasia of neointima and inflammation are one of the main features of atherosclerosis. Therefore, targeting TCF21 may become a potential treatment for relieving atherosclerosis.

KEY MESSAGES

TCF21 as a member of basic helix-loop-helix transcription factors regulates cell growth and differentiation by modulating gene expression during the development of different organs and plays an important role in cardiovascular development and disease. VSMCs and cells derived from VSMCs constitute the majority of plaques in atherosclerosis. TCF21 plays a key role in regulation of VSMCs' phenotype, thus accelerating atherogenesis in the early stage. However, TCF21 enhances plaque stability in late-stage atherosclerosis. The dual role of TCF21 should be considered in the translational medicine.

Downregulation of LILRB4 Promotes Human Aortic Smooth Muscle Cell Contractile Phenotypic Switch and Apoptosis in Aortic Dissection

Aortic dissection (AD) is a severe vascular disease with high rates of mortality and morbidity. However, the underlying molecular mechanisms of AD remain unclear. Differentially expressed genes (DEGs) were screened by bioinformatics methods. Alterations of histopathology and inflammatory factor levels in β-aminopropionitrile (BAPN)-induced AD mouse model were evaluated through Hematoxylin-Eosin (HE) staining and Enzyme-linked immunosorbent assay (ELISA), respectively. Reverse transcription quantitative real-time polymerase chain reaction was performed to detect DEGs expression. Furthermore, the role of LILRB4 in AD was investigated through Cell Counting Kit-8 (CCK-8), wound healing, and flow cytometry. Western blotting was employed to assess the phenotypic switch and extracellular matrix (ECM)-associated protein expressions in platelet-derived growth factor-BB (PDGF-BB)-stimulated in vitro model of AD. In the AD mouse model, distinct dissection formation was observed. TNF-α, IL-1β, IL-8, and IL-6 levels were higher in the AD mouse model than in the controls. Six hub genes were identified, including LILRB4, TIMP1, CCR5, CCL7, MSR1, and CLEC4D, all of which were highly expressed. Further exploration revealed that LILRB4 knockdown inhibited the cell vitality and migration of PDGF-BB-induced HASMCs while promoting apoptosis and G0/G1 phase ratio. More importantly, LILRB4 knockdown promoted the protein expression of α-SMA and SM22α, while decreasing the expression of Co1, MMP2, and CTGF, which suggested that LILRB4 silencing promoted contractile phenotypic transition and ECM stability. LILRB4 knockdown inhibits the progression of AD. Our study provides a new potential target for the clinical treatment of AD.

Senescence-associated inflammation and inhibition of adipogenesis in subcutaneous fat in Werner syndrome

Werner syndrome (WS) is a hereditary premature aging disorder characterized by visceral fat accumulation and subcutaneous lipoatrophy, resulting in severe insulin resistance. However, its underlying mechanism remains unclear. In this study, we show that senescence-associated inflammation and suppressed adipogenesis play a role in subcutaneous adipose tissue reduction and dysfunction in WS. Clinical data from four Japanese patients with WS revealed significant associations between the decrease of areas of subcutaneous fat and increased insulin resistance measured by the glucose clamp. Adipose-derived stem cells from the stromal vascular fraction derived from WS subcutaneous adipose tissues (WSVF) showed early replicative senescence and a significant increase in the expression of senescence-associated secretory phenotype (SASP) markers. Additionally, adipogenesis and insulin signaling were suppressed in WSVF, and the expression of adipogenesis suppressor genes and SASP-related genes was increased. Rapamycin, an inhibitor of the mammalian target of rapamycin (mTOR), alleviated premature cellular senescence, rescued the decrease in insulin signaling, and extended the lifespan of WS model of C. elegans. To the best of our knowledge, this study is the first to reveal the critical role of cellular senescence in subcutaneous lipoatrophy and severe insulin resistance in WS, highlighting the therapeutic potential of rapamycin for this disease.

Dynamic chromatin architecture of the porcine adipose tissues with weight gain and loss

Using an adult female miniature pig model with diet-induced weight gain/weight loss, we investigated the regulatory mechanisms of three-dimensional (3D) genome architecture in adipose tissues (ATs) associated with obesity. We generated 249 high-resolution in situ Hi-C chromatin contact maps of subcutaneous AT and three visceral ATs, analyzing transcriptomic and chromatin architectural changes under different nutritional treatments. We find that chromatin architecture remodeling underpins transcriptomic divergence in ATs, potentially linked to metabolic risks in obesity development. Analysis of chromatin architecture among subcutaneous ATs of different mammals suggests the presence of transcriptional regulatory divergence that could explain phenotypic, physiological, and functional differences in ATs. Regulatory element conservation analysis in pigs and humans reveals similarities in the regulatory circuitry of genes responsible for the obesity phenotype and identified non-conserved elements in species-specific gene sets that underpin AT specialization. This work provides a data-rich tool for discovering obesity-related regulatory elements in humans and pigs.

Non-coding RNA-based therapeutics in cancer therapy: An emphasis on Wnt/β-catenin control

Non-coding RNA transcripts are RNA molecules that have mainly regulatory functions and they do not encode proteins. microRNAs (miRNAs), lncRNAs and circRNAs are major types of this family and these epigenetic factors participate in disease pathogenesis, especially cancer that their abnormal expression may lead to cancer progression. miRNAs and lncRNAs possess a linear structure, whereas circRNAs possess ring structures and high stability. Wnt/β-catenin is an important factor in cancer with oncogenic function and it can increase growth, invasion and therapy resistance in tumors. Wnt upregulation occurs upon transfer of β-catenin to nucleus. Interaction of ncRNAs with Wnt/β-catenin signaling can determine tumorigenesis. Wnt upregulation is observed in cancers and miRNAs are able to bind to 3'-UTR of Wnt to reduce its level. LncRNAs can directly/indirectly regulate Wnt and in indirect manner, lncRNAs sponge miRNAs. CircRNAs are new emerging regulators of Wnt and by its stimulation, they increase tumor progression. CircRNA/miRNA axis can affect Wnt and carcinogenesis. Overall, interaction of ncRNAs with Wnt can determine proliferation rate, migration ability and therapy response of cancers. Furthermore, ncRNA/Wnt/β-catenin axis can be utilized as biomarker in cancer and for prognostic applications in patients.

Novel TCF21high pericyte subpopulation promotes colorectal cancer metastasis by remodelling perivascular matrix

OBJECTIVE

Haematogenous dissemination is a prevalent route of colorectal cancer (CRC) metastasis. However, as the gatekeeper of vessels, the role of tumour pericytes (TPCs) in haematogenous metastasis remains largely unknown. Here, we aimed to investigate the heterogeneity of TPCs and their effects on CRC metastasis.

DESIGN

TPCs were isolated from patients with CRC with or without liver metastases and analysed by single-cell RNA sequencing (scRNA-seq). Clinical CRC specimens were collected to analyse the association between the molecular profiling of TPCs and CRC metastasis. RNA-sequencing, chromatin immunoprecipitation-sequencing and bisulfite-sequencing were performed to investigate the TCF21-regulated genes and mechanisms underlying integrin α5 on TCF21 DNA hypermethylation. Pericyte-conditional Tcf21-knockout mice were constructed to investigate the effects of TCF21 in TPCs on CRC metastasis. Masson staining, atomic force microscopy, second-harmonic generation and two-photon fluorescence microscopy were employed to observe perivascular extracellular matrix (ECM) remodelling.

RESULTS

Thirteen TPC subpopulations were identified by scRNA-seq. A novel subset of TCF21^high TPCs, termed 'matrix-pericytes', was associated with liver metastasis in patients with CRC. TCF21 in TPCs increased perivascular ECM stiffness, collagen rearrangement and basement membrane degradation, establishing a perivascular metastatic microenvironment to instigate colorectal cancer liver metastasis (CRCLM). Tcf21 depletion in TPCs mitigated perivascular ECM remodelling and CRCLM, whereas the coinjection of TCF21^high TPCs and CRC cells markedly promoted CRCLM. Mechanistically, loss of integrin α5 inhibited the FAK/PI3K/AKT/DNMT1 axis to impair TCF21 DNA hypermethylation in TCF21^high TPCs.

CONCLUSION

This study uncovers a previously unidentified role of TPCs in haematogenous metastasis and provides a potential diagnostic marker and therapeutic target for CRC metastasis.

Tcf21 marks visceral adipose mesenchymal progenitors and functions as a rate-limiting factor during visceral adipose tissue development

Distinct locations of different white adipose depots suggest anatomy-specific developmental regulation, a relatively understudied concept. Here, we report a population of Tcf21 lineage cells (Tcf21 LCs) present exclusively in visceral adipose tissue (VAT) that dynamically contributes to VAT development and expansion. During development, the Tcf21 lineage gives rise to adipocytes. In adult mice, Tcf21 LCs transform into a fibrotic or quiescent state. Multiomics analyses show consistent gene expression and chromatin accessibility changes in Tcf21 LC, based on which we constructed a gene-regulatory network governing Tcf21 LC activities. Furthermore, single-cell RNA sequencing (scRNA-seq) identifies the heterogeneity of Tcf21 LCs. Loss of Tcf21 promotes the adipogenesis and developmental progress of Tcf21 LCs, leading to improved metabolic health in the context of diet-induced obesity. Mechanistic studies show that the inhibitory effect of Tcf21 on adipogenesis is at least partially mediated via Dlk1 expression accentuation.

Hypoxia as a Double-Edged Sword to Combat Obesity and Comorbidities

The global epidemic of obesity is tightly associated with numerous comorbidities, such as type II diabetes, cardiovascular diseases and the metabolic syndrome. Among the key features of obesity, some studies have suggested the abnormal expansion of adipose-tissue-induced local endogenous hypoxic, while other studies indicated endogenous hyperoxia as the opposite trend. Endogenous hypoxic aggravates dysfunction in adipose tissue and stimulates secretion of inflammatory molecules, which contribute to obesity. In contrast, hypoxic exposure combined with training effectively generate exogenous hypoxic to reduce body weight and downregulate metabolic risks. The (patho)physiological effects in adipose tissue are distinct from those of endogenous hypoxic. We critically assess the latest advances on the molecular mediators of endogenous hypoxic that regulate the dysfunction in adipose tissue. Subsequently we propose potential therapeutic targets in adipose tissues and the small molecules that may reverse the detrimental effect of local endogenous hypoxic. More importantly, we discuss alterations of metabolic pathways in adipose tissue and the metabolic benefits brought by hypoxic exercise. In terms of therapeutic intervention, numerous approaches have been developed to treat obesity, nevertheless durability and safety remain the major concern. Thus, a combination of the therapies that suppress endogenous hypoxic with exercise plans that augment exogenous hypoxic may accelerate the development of more effective and durable medications to treat obesity and comorbidities.

Associations of Transcription Factor 21 Gene Polymorphisms with the Growth and Body Composition Traits in Broilers

Simple Summary

The functional SNPs discovered in this work will give helpful information on the crucial molecular markers that may be employed in breeding efforts to improve the heart development of broiler chickens.

Abstract

This study aims to identify molecular marker loci that could be applied in broiler breeding programs. In this study, we used public databases to locate the Transcription factor 21 (TCF21) gene that affected the economically important traits in broilers. Ten single nucleotide polymorphisms were detected in the TCF21 gene by monoclonal sequencing. The polymorphisms of these 10 SNPs in the TCF21 gene were significantly associated (p < 0.05) with multiple growth and body composition traits. Furthermore, the TT genotype of g.-911T>G was identified to significantly increase the heart weight trait without affecting the negative traits, such as abdominal fat and reproduction by multiple methods. Thus, it was speculated that the g.-911T>G identified in the TCF21 gene might be used in marker-assisted selection in the broiler breeding program.

The adipokine orosomucoid alleviates adipose tissue fibrosis via the AMPK pathway

The excess deposition of underlying extracellular matrix (ECM) in adipose tissue is defined as adipose tissue fibrosis that is a major contributor to metabolic disorder such as obesity and type 2 diabetes. Anti-fibrosis therapy has received much attention in the treatment of metabolic disorders. Orosomucoid (ORM) is an acute-phase protein mainly produced by liver, which is also an adipokine. In this study, we investigated the effects of ORM on adipose tissue fibrosis and the potential mechanisms. We showed that ORM1-deficient mice exhibited an obese phenotype, manifested by excessive collagen deposition in adipose tissues and elevated expression of ECM regulators such as metalloproteinases (MMP-2, MMP-13, MMP-14) and tissue inhibitors of metalloproteinases (TIMP-1, TIMP-2, TIMP-3). Administration of exogenous ORM (50 mg· kg^-1· d^-1, ip) for 7 consecutive days in high-fat diet (HFD)-fed mice and leptin receptor (LepR)-deficient db/db mice attenuated these abnormal expressions. Meanwhile, ORM administration stimulated AMP-activated protein kinase (AMPK) phosphorylation and decreased transforming growth factor-β1 (TGF-β1) level in adipose tissues of the mice. In TGF-β1-treated 3T3-L1 fibroblasts, ORM (10 μg/mL) improved the impaired expression profiles of fibrosis-related genes, whereas a selective AMPK inhibitor dorsomorphin (1 μmol/mL) abolished these effects. Together, our results suggest that ORM exerts a direct anti-fibrosis effect in adipose tissue via AMPK activation. ORM is expected to become a novel target for the treatment of adipose tissue fibrosis.

Single-cell chromatin accessibility and lipid profiling reveals SCD1-dependent metabolic shift in adipocytes induced by bariatric surgery

Obesity promotes type 2 diabetes and cardiometabolic pathologies. Vertical sleeve gastrectomy (VSG) is used to treat obesity resulting in long-term weight loss and health improvements that precede weight loss; however, the mechanisms underlying the immediate benefits remain incompletely understood. Because adipose plays a crucial role in energy homeostasis and utilization, we hypothesized that VSG exerts its influences, in part, by modulating adipose functional states. We applied single-cell ATAC sequencing and lipid profiling to inguinal and epididymal adipose depots from mice that received sham surgery or VSG. We observed depot-specific cellular composition and chromatin accessibility patterns that were altered by VSG. Specifically, accessibility at Scd1, a fatty acid desaturase, was substantially reduced after VSG in mature adipocytes of inguinal but not epididymal depots. This was accompanied by reduced accumulation of SCD1-produced unsaturated fatty acids. Given these findings and reports that reductions in Scd1 attenuate obesity and insulin resistance our results suggest VSG exerts its beneficial effects through an inguinal depot-specific reduction of SCD1 activity.

miR-6745-TIMP1 axis inhibits cell growth and metastasis in gastric cancer

Tissue inhibitor matrix metalloproteinase 1 (TIMP1) has been reported to act as a tumor oncogene in colon cancer. However, little is known about the biological role of TIMP1 in gastric cancer. In this study, we found that the expression of TIMP1 in GC tissues was upregulated compared with the normal gastric tissues. TIMP1 was confirmed as a direct target of miR-6745 and silencing TIMP1 mimicked the effects of miR-6745 in GC cells. Further mechanism studies have shown that miR-6745 inhibits the Wnt/β-catenin pathway by targeting TIMP1, thereby inhibiting cell proliferation, migration and invasion. In addition, through the analysis of GC tissues, a negative correlation between miR-6745 and TIMP1 was found in 42 GC tissues. Our findings indicate that the miR-6745-TIMP1 axis regulates Wnt/βcatenin signaling and participates in GC tumorigenesis and provide a potential therapeutic target for preventing GC progression.

Upregulation of TCF21 inhibits migration of adrenocortical carcinoma cells

BACKGROUND

Adrenocortical carcinomas (ACC) are rare and aggressive cancer. Our previous study has revealed that the transcription factor 21, TCF21, is downregulated in ACC and regulates steroidogenic factor 1 (SF-1) binding to the SF-1 E-box promoter. In addition, it could be found that TCF21 is a predictor of overall survival (OS) in adult carcinomas.

METHODS

In this study, it was investigated the correlation between TCF21 expression and the promoter methylation status in adrenocortical tumor cells, carcinomas and adenoma. The biological function and potential molecular mechanism of TCF21 restoration in migration and invasion of ACC cells was examined.

RESULTS

We could be demonstrated a negative correlation between the level of TCF21 expression and methylation of its promoter in adenoma and carcinoma cells indicating the epigenetic control of TCF21 expression. It was also demonstrated that the expression of TCF21 inhibits migration and invasion in the ACC cell line, H295R cells, using plasmid transfection to express TCF21. Furthermore, it could be investigated the TCF21 function as tumor suppressor probably through Kisspeptin 1 (KISS-1) expression and epithelial-mesenchymal transition (EMT) reversion, as well as the modulation of several metalloproteinases in ACC cells.

CONCLUSIONS

Our results suggest that enhancement of TCF21 expression levels may be a potential strategy to revert invasive abilities in adrenocortical carcinomas.

Fight against fibrosis in adipose tissue remodeling

Adipose is a key tissue regulating energy homeostasis. In states of obesity, caloric intake exceeds energy expenditure, thereby accelerating lipid accumulation with ongoing extracellular matrix (ECM) remodeling. Excess deposition of lipids and expansion of adipocytes potentially decrease ECM flexibility with local hypoxia and inflammation. Hypoxia and chronic low-grade inflammation accelerate the development of adipose tissue fibrosis and related metabolic dysfunctions. Recent research investigated that some cytokines and proteins are functional in regulating energy homeostasis, meanwhile, are potential targets to fight against adipose tissue fibrosis and insulin resistance. In this review, we focused on the regulatory mechanisms and mediators in remodeling of adipose tissue fibrosis, along with their relevance to clinical manifestations.

Distinct fibroblast functional states drive clinical outcomes in ovarian cancer and are regulated by TCF21

Recent studies indicate that cancer-associated fibroblasts (CAFs) are phenotypically and functionally heterogeneous. However, little is known about CAF subtypes, the roles they play in cancer progression, and molecular mediators of the CAF “state.” Here, we identify a novel cell surface pan-CAF marker, CD49e, and demonstrate that two distinct CAF states, distinguished by expression of fibroblast activation protein (FAP), coexist within the CD49e⁺ CAF compartment in high-grade serous ovarian cancers. We show for the first time that CAF state influences patient outcomes and that this is mediated by the ability of FAP-high, but not FAP-low, CAFs to aggressively promote proliferation, invasion and therapy resistance of cancer cells. Overexpression of the FAP-low–specific transcription factor TCF21 in FAP-high CAFs decreases their ability to promote invasion, chemoresistance, and in vivo tumor growth, indicating that it acts as a master regulator of the CAF state. Understanding CAF states in more detail could lead to better patient stratification and novel therapeutic strategies.

Concise Review: Adipose-Derived Stem Cells (ASCs) and Adipocyte-Secreted Exosomal microRNA (A-SE-miR) Modulate Cancer Growth and proMote Wound Repair

Adipose-derived stem cells (ASCs) have been routinely used from several years in regenerative surgery without any definitive statement about their potential pro-oncogenic or anti-oncogenic role. ASCs has proven to favor tumor progression in several experimental cancer models, playing a central role in regulating tumor invasiveness and metastatic potential through several mechanisms, such as the paracrine release of exosomes containing pro-oncogenic molecules and the induction of epithelial-mesenchymal transition. However, the high secretory activity and the preferential tumor-targeting make also ASCs a potentially suitable vehicle for delivery of new anti-cancer molecules in tumor microenvironment. Nanotechnologies, viral vectors, drug-loaded exosomes, and micro-RNAs (MiR) represent additional new tools that can be applied for cell-mediated drug delivery in a tumor microenvironment. Recent studies revealed that the MiR play important roles in paracrine actions on adipose-resident macrophages, and their dysregulation has been implicated in the pathogenesis of obesity, diabetes, and diabetic complications as wounds. Numerous MiR are present in adipose tissues, actively participating in the regulation of adipogenesis, adipokine secretion, inflammation, and inter-cellular communications in the local tissues. These results provide important insights into Adipocyte-secreted exosomal microRNA (A-SE-MiR) function and they suggest evaluating the potential role of A-SE-MiR in tumor progression, the mechanisms underlying ASCs-cancer cell interplay and clinical safety of ASCs-based therapies.

Are IL1B, IL6 and IL6R Gene Variants Associated with Anterior Cruciate Ligament Rupture Susceptibility?

Cytokines, such as interleukins, are crucial in regulating critical cell signaling pathways as well as being major contributors to inflammatory response and are upregulated during ligament and tendon injuries. The genes encoding key interleukins, such as IL1B and IL6 as well as interleukin receptor IL6R, were chosen as candidate genes for association with soft tissue injuries. The aim of the case-control study was to verify the hypothesis that sequence variants rs1143627, rs16944, rs1800795, rs2228145 in the IL1B, IL6 and IL6R genes are associated with ACL rupture susceptibility in a Polish population. Among four analyzed SNPs, the rs1800795 IL6 gene polymorphism was found to be the only one significantly associated with ACL rupture (p = 0.010, p = 0.022, p = 0.004 for codominant, recessive and overdominant models, respectively; odds ratio = 1.74, 95% CI 1.08-2.81, sex adjusted p = 0.032 for recessive model). With reference to the other analyzed polymorphisms, we failed to show significant differences in the genotype and allele frequencies for IL6R rs2228145as well as IL1B rs16944 and rs1143627 (analyzed alone or in haplotype combination) between the ACL rupture group and the healthy control group among Polish participants. Due to the nature of case-control studies, the results of this study need to be confirmed in independent studies with larger sample sizes.

Fibro-Adipogenic Remodeling of the Diaphragm in Obesity-Associated Respiratory Dysfunction

Respiratory dysfunction is a common complication of obesity, conferring cardiovascular morbidity and increased mortality and often necessitating mechanical ventilatory support. While impaired lung expansion in the setting of increased adipose mass and reduced central response to hypercapnia have been implicated as pathophysiological drivers, the impact of obesity on respiratory muscles-in particular, the diaphragm-has not been investigated in detail. Here, we demonstrate that chronic high-fat diet (HFD) feeding impairs diaphragm muscle function, as assessed in vivo by ultrasonography and ex vivo by measurement of contractile force. During an HFD time course, progressive adipose tissue expansion and collagen deposition within the diaphragm parallel contractile deficits. Moreover, intradiaphragmatic fibro-adipogenic progenitors (FAPs) proliferate with long-term HFD feeding while giving rise to adipocytes and type I collagen-depositing fibroblasts. Thrombospondin 1 (THBS1), a circulating adipokine, increases with obesity and induces FAP proliferation. These findings suggest a novel role for FAP-mediated fibro-adipogenic diaphragm remodeling in obesity-associated respiratory dysfunction.

Beneficial alterations in body composition, physical performance, oxidative stress, inflammatory markers, and adipocytokines induced by long-term high-intensity interval training in an aged rat model

Sarcopenia is associated with loss of muscle mass and function as well as oxidative stress, chronic low-grade inflammatory status, and adipocytokine dysfunction. It has been reported that sarcopenia can be attenuated by exercise training. The purpose of this study was to evaluate whether long-term high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) protocols could differentially modulate changes in body composition, physical performance, inflammatory parameters, and adipocytokines in fat tissues and serum, as well as oxidative parameters and insulin-like growth factor 1 (IGF-1) levels in skeletal muscle tissue of aged rats. Middle-aged (18-month-old) female Sprague Dawley rats (n = 36) were subjected to 8 months of MICT (26-m MICT) or HIIT (26-m HIIT) treadmill training (45 min, 5 times per week), and the results were compared with those of age-matched sedentary controls (26-m SED); 8-month-old (8-m SED) and 18-month-old (18-m SED) rats served as aging sedentary controls. Body composition parameters; physical performance; serum and skeletal muscle oxidative stress parameters; levels of IGF-1, a serum and fat tissue inflammatory marker; adipocytokine (leptin, adiponectin) levels; and plasma glucose and lipid metabolism-related parameters were analyzed among the five groups. The percent fat and body fat to lean mass ratio increased as a main effect with age, whereas 26-m HIIT but not 26-m MICT attenuated these alterations. The 26-m HIIT group showed a larger improvement in grip strength compared to that of 26-m MICT, with a similar increase in inclined plane performance, maximum running speed, and exhaustion over time as compared with the 26-m SED group. Notably, the 26-m HIIT group showed lower high-sensitivity C-reactive protein levels and higher IL-10 in serum compared with those of the 26-m SED and 26-m MICT groups. Both exercise protocols promoted increased skeletal muscle IGF-1 and decreased serum IGF-1 and adiponectin relative to those in the 26-m SED group, whereas only 26-m HIIT dampened the age-related decrease in plasma free fatty acids and increased serum leptin, along with providing lower fat tissue leptin as compared with that in the 26-m SED group. Moreover, the 26-m HIIT group showed lower serum and skeletal muscle malonylaldehyde and skeletal muscle 8-hydroxydeoxyguanosine (8-OHdG) levels than those in the 26-m MICT group, albeit similar decreases in serum and skeletal muscle 4-hydroxynonenal and serum 8-OHdG and increases in skeletal muscle superoxide dismutase 2 activity. In conclusion, HIIT initiated late in life exhibited greater beneficial effects in ameliorating aged-related elevations in oxidative stress and inflammation, as well as dysfunction of circulating adipocytokine levels, than a volume-matched MICT program. HIIT may therefore contribute to improvements in body composition and physical performance changes associated with aging.

Transcription factor 21 regulates expression of ERβ and SF-1 via upstream stimulatory factor-2 in endometriotic tissues

Steroidogenic factor-1 (SF-1, encoded by NR5A1) and estrogen receptor beta (ERβ, encoded by ESR2), which are highly expressed in endometriotic stromal cells (ESCs), contribute to the pathogenesis of endometriosis, but the regulation mechanism remains largely unknown. Transcription factor 21 (TCF21) belongs to the helix-loop-helix (bHLH) family characterized by regulating gene expression via binding to E-box element. Here, we attempted to determine the molecular mechanism of TCF21 on SF-1 and ERβ expression in endometriosis. We found that TCF21 expression in ESCs was higher than that in endometrial stromal cells (EMs), and positively correlated with SF-1 and ERβ expression in ESCs. Since the importance of E-box element for NR5A1 promoter activity has been previously reported, we performed site-mutation and luciferase assay, revealing that the E-box sequence in the ESR2 promoter is also a critical element modulating ERβ expression. Upstream stimulatory factor 2 (USF2) is another bHLH factor implicated in transcriptional regulation. Further analyses elucidated that it is not TCF21, but USF2 exhibited higher binding affinities in ESCs to NR5A1 and ESR2 promoters than in EMs. Additionally, TCF21 knockdown significantly decreased the binding activities of USF2 to NR5A1 and ESR2 promoters via disruption of the TCF21-USF2 complex. Meanwhile, manipulating TCF21 expression significantly affected MMP9 and cyclinD1 expression, as wells as proliferation and invasion of ESCs. Moreover, TCF21 depletion in endometriotic xenografts reduced SF-1 and ERβ expression, abrogating ectopic lesion growth in mice. Cumulatively, a critical role of TCF21 in the pathogenesis of endometriosis is demonstrated, suggesting a potential druggable target for future therapy.