COL1A1 Expression Research Articles

Progression from cardiomyopathy to heart failure with reduced ejection fraction: A CORIN deficient course

Cardiomyopathies, encompassing hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM), constitute a diverse spectrum of heart muscle diseases that often culminating in heart failure (HF). The inherent molecular heterogeneity of these conditions has implications for prognosis and therapeutic strategies.Publicly available microarray and RNA sequencing (RNA-seq) data sets of HCM (n = 106 from GSE36961) and DCM (n = 18 from GSE135055 and 166 from GSE141910) patients were employed for our analysis. The Non-negative Matrix Factorization (NMF) algorithm was applied to explore the molecular stratification within HCM and DCM, and enrichment analysis was performed to delineate their biological characteristics. By integrating bulk and single-nucleus RNA-seq (snRNA-seq) data, we identified a potential biomarker for HCM progression and cardiac fibrosis, which was subsequently validated using mendelian randomization and in vitro.Our application of NMF identified two distinct molecular clusters. Particularly, a profibrotic, heart failure with reduced ejection fraction (HFrEF)-resembling Cluster 1 emerged, characterized by diminished expression of CORIN and a high degree of fibroblast activation. This cluster also exhibited lower left ventricular ejection fraction (LVEF) and worse prognostic outcomes, establishing the significance of this molecular subclassification. We further found that overexpression of CORIN could mitigate TGFβ1-induced expression of col1a1 and α-SMA in neonatal rat cardiac fibroblasts.Our results indicated the heterogeneity of HCM population, and further evidenced the participation of corin in the progression of HCM, DCM and HFrEF. Nevertheless, our study is constrained by the lack of corresponding clinical data and experimental validation of the identified subtypes. Therefore, further studies are warranted to elucidate the downstream pathways of corin and to validate these findings in independent patient cohorts.

Abstract P232: Estradiol Supplementation Prevents Ovariectomy-Induced Arterial Stiffness and Vascular Fibrosis

Background: Arterial stiffness is an independent predictor of cardiovascular events and mortality. Clinical data shows arterial stiffness increases rapidly after menopause, but mechanisms that mediate this change are not well known. The effect of ovariectomy (ovx) in rodent models is inconsistent in the literature. We hypothesize that the loss of estradiol (E2) contributes to ovx-induced arterial stiffening in a mouse model via fibrotic mechanisms, and that restoration of E2 will prevent these changes. Methods: Eight-week-old female C57/Bl6J mice received bilateral ovx or sham operation. Subcutaneous placebo or E2 (0.36 mg/day) pellets were implanted 2 weeks later to achieve three groups (sham+placebo, ovx+placebo, and ovx+E2). Aortic pulse wave velocity (PWV) was measured as an index of arterial stiffness. Blood pressure (BP) was measured by radiotelemetry. Aortic fibrosis was assessed by histological quantification of Masson’s trichrome staining and expressed as fold change in %fibrosis from sham. Pro-fibrotic genes were assessed in aortic tissue via quantitative PCR. Data presented are mean ± SEM. Results: Successful ovx was confirmed by reduction in uterine weight in the ovx group compared with other groups ( p <0.0001). At 6-weeks-post-surgery (N=16-18/group), PWV was increased in ovx (5.2±0.2 mm/ms) versus sham (3.4±0.1 mm/ms, p <0.0001) and ovx+E2 (3.5±0.1 mm/ms, p <0.0001) groups. In biweekly measures (N=4-5/group), PWV was greater in the ovx group at 4- and 6-weeks-post-surgery compared with sham ( p <0.0001) and ovx+E2 ( p <0.0001) groups, while PWV in the ovx+E2 group did not differ from sham at any time ( p ≥0.6). At 6-weeks post-surgery (N=5/group), there were no observed differences between groups for dark or light cycle systolic or diastolic BP, mean arterial pressure, or pulse pressure. Aortic fibrosis was increased in the ovx group (1.6-fold) compared with sham ( p =0.03) and ovx+E2 (0.9-fold, p =0.02) groups (N=10-12/group). Aortic fibrosis correlated with PWV at 6-weeks-post-surgery (R 2 =0.25, p <0.01). Aortic mRNA expression of collagen1a1 was increased in ovx versus ovx+E2 mice ( p =0.04, N=4-6/group). Conclusion: In conclusion, the restoration of E2 prevents ovx-driven arterial stiffening in female mice via a reduction in fibrotic remodeling of the aorta. The results also support that ovx is an appropriate model to study the mechanisms of menopause-induced arterial stiffening and that anti-fibrotic therapeutics may be beneficial in aging women.

CAF-Associated Genes in Breast Cancer for Novel Therapeutic Strategies.

Breast cancer (BC) is the most common cancer in women, and therapeutic strategies for it are based on the molecular subtypes of luminal BC, HER2 BC, and triple-negative BC (TNBC) because each subtype harbors different unique genetic aberrations. Recently, features of the tumor microenvironment (TME), especially cancer-associated fibroblasts (CAFs), have been demonstrated to play a critical role in BC progression, and we would like to understand the molecular features of BC CAFs for novel therapeutic strategies. In a recent study, 115 CAF-associated genes (CAFGs) were identified in a public database of microdissection and microarray data (GSE35602) from 13 colorectal cancer (CRC) tumors. Using a public database (GSE10797) of 28 BC tumors, a similar analysis was performed. In BC, 59 genes from the 115 CAFGs identified in CRC (CRC CAFGs) were also closely associated with a CAFs marker, SPARC (R = 0.6 or beyond), and POSTN was of particular interest as one of the BC CAFGs with the highest expression levels and a close association with SPARC expression (R = 0.94) in the cancer stroma of BC tumors. In BC stroma, POSTN was followed in expression levels by DKK3, MMP2, PDPN, and ACTA2. Unexpectedly, FAP and VIM were not as highly associated with SPARC expression in the cancer stroma of BC tumors and exhibited low expression. These findings suggested that ACTA2 might be the most relevant conventional CAFs marker in BC, and ACTA2 was actually correlated in expression with many CRC CAFGs, such as SPARC. Surprisingly, the SE ratio values of the BC CAFGs were much lower (average SE = 3.8) than those of the CRC CAFGs (SE = 10 or beyond). We summarized the current understanding of BC CAFs from the literature. Finally, in triple-negative BC (TNBC) (n = 5), SPARC expression uniquely showed a close association with COL11A1 and TAGLN expression, representing a myofibroblast (myCAFs) marker in the cancer stroma of the BC tumors, suggesting that myCAFs may be molecularly characterized by TNBC in contrast to other BC phenotypes. In summary, CAFs could have unique molecular characteristics in BC, and such TME uniqueness could be therapeutically targeted in BC.

Delay the progression of glucocorticoid-induced osteoporosis: Fraxin targets ferroptosis via the Nrf2/GPX4 pathway.

Glucocorticoid-induced osteoporosis (GIOP) commonly accelerates bone loss, increasing the risk of fractures and osteonecrosis more significantly than traditional menopausal osteoporosis. The extracellular environment influenced by glucocorticoids heightens fracture and osteonecrosis risks. Fraxin (Fra), a key component of the traditional Chinese herbal remedy Cortex Fraxini, is known for its wide-ranging pharmacological effects, but its impact on GIOP remains unexplored. This investigation aims to delineate the effects and underlying mechanisms of Fra in combating dexamethasone (Dex)-induced ferroptosis and GIOP. We established a mouse model of GIOP via intraperitoneal injections of Dex and cultured osteoblasts with Dex treatment for in vitro analysis. We evaluated the impact of Fra on Dex-treated osteoblasts through assays such as C11-BODIPY and FerroOrange staining, mitochondrial functionality tests, and protein expression analyses via Western blot and immunofluorescence. The influence of Fra on bone microarchitecture of GIOP in mice was assessed using microcomputerized tomography, hematoxylin and eosin staining, double-labeling with Calcein-Alizarin Red S, and immunohistochemistry at imaging and histological levels. Based on our data, Fra prevented Dex-induced ferroptosis and bone loss. In vitro, glutathione levels increased and malondialdehyde, lipid peroxidation, and mitochondrial reactive oxygen species decreased. Fra treatment also increases nuclear factor erythroid 2-related factor 2 (Nrf2), glutathione peroxidase 4 (GPX4), and COL1A1 expression and promotes bone formation. To delve deeper into the mechanism, the findings revealed that Fra triggered the activation of Nrf2/GPX4 signaling. Moreover, the use of siRNA-Nrf2 blocked the beneficial effect of Fra in osteoblasts cultivated with Dex. Fra effectively combats GIOP by activating the Nrf2/GPX4 signaling pathway to inhibit ferroptosis.

Effect of 660-nm LED photobiomodulation on the proliferation and chondrogenesis of meniscus-derived stem cells (MeSCs)

Meniscus-derived stem cells (MeSCs), a unique type of MSC, have outstanding advantages in meniscal cytotherapy and tissue engineering, but the effects and molecular mechanisms of PBM on MeSCs are still unclear. We used 660-nm LED light with different energy densities to irradiate six human MeSC samples and tested their proliferation rate via cell counting, chondrogenic differentiation capacity via the DMMB assay, mitochondrial activity via the MTT assay, and gene expression via qPCR. The proliferation ability, chondrogenic capacity and mitochondrial activity of the 18 J/cm2 group were greater than those of the 4 J/cm2 and control groups. The mRNA expression levels of Akt, PI3K, TGF-β3, Ki67 and Notch-1 in the 18 J/cm2 group were greater than those in the other groups in most samples. After chondrogenic induction, the expression of Col2A1, Sox9 and Aggrecan in the 18 J/cm2 group was significantly greater than that in the 4 J/cm2 and control groups in most of the samples. The variation in the MTT values and Src, PI3K, Akt, mTOR and GSK3β levels decreased with time. The results showed that 660-nm LED red light promoted proliferation and chondrogenic differentiation and affected the gene expression of MeSCs, and the effects on gene expression and mitochondrial activity decreased with time.

Development of the insect adult fat body relies on glycolysis, lipid synthesis, cell proliferation, and cell adhesion.

The fat body of the holometabolous insect is remodeled by the degradation of the larval fat body and the development of the adult fat body during metamorphosis. However, the mechanism of adult fat body development is quite unclear. Using the agricultural pest Helicoverpa armigera, the cotton bollworm, as a model, we revealed that the development of adult fat body was regulated by glycolysis, triglyceride (triacylglycerol [TAG]) synthesis, cell proliferation, and cell adhesion. RNA sequencing detected a set of genes that were upregulated in the 8-d late pupal fat body at a late metamorphic stage compared with the 2-d pupal fat body at an earlier metamorphic stage. The pathways for glycolysis, TAG synthesis, cell proliferation, and cell adhesion were enriched by the differentially expressed genes, and the key genes linked with these pathways showed increased expression in the 8-d pupal fat body. Knockdown of phosphofructokinase (Pfk), acetyl-CoA carboxylase (Acc1), phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit (P110) and collagen alpha-1(IV) chain (Col4a1) by RNA interference resulted in abnormal eclosion and death at pupal stages, and repressed lipid droplets accumulation and adult fat body development. The expression of Acc1, P110, and Col4a1 was repressed by the insect steroid hormone 20-hydroxyecdysone (20E). The critical genes in the 20E pathway appeared to decrease at the late pupal stage. These data suggested that the development of the insect adult fat body is regulated by glycolysis, lipids synthesis, cell proliferation, and cell adhesion at the late pupal stage when the 20E signal decreases.

Glutamine metabolism promotes human trophoblast cell invasion via COL1A1 mediated by PI3K-AKT pathway

Abnormal trophoblast invasion function is an important cause of recurrent spontaneous abortion (RSA). Recent research has revealed a connection between glutamine metabolism and RSA. However, the interplay between these three factors and their related mechanisms remains unclear. To address this issue, we collected villus tissues from 10 healthy women with induced abortion and from 10 women with RSA to detect glutamine metabolism. Then, the trophoblast cell line HTR-8/SVneo was used in vitro to explore the effect of glutamine metabolism on trophoblast cells invasion, which was tested by transwell assay. We found that the concentration of glutamine in the villi of the normal pregnancy group was significantly higher than that in the RSA group. Correspondingly, the expression levels of key enzymes involved in glutamine synthesis and catabolism, including glutamine synthetase and glutaminase, were significantly higher in the villi of the normal pregnancy group. Regarding trophoblast cells, glutamine markedly enhanced the proliferative and invasive abilities of HTR-8/SVneo cells. Additionally, collagen type I alpha 1 (COL1A1) was confirmed to be a downstream target of glutamine, and glutamine also activated the PI3K-AKT pathway in HTR-8/SVneo cells. These findings indicate that glutamine metabolism facilitates the invasion of trophoblasts by up-regulating COL1A1 expression through the activation of the PI3K-AKT pathway, but the specific mechanism of COL1A1 requires further study.

Network Pharmacology, Molecular Docking Analysis and Experiment Validations on Molecular Targets and Mechanisms of the Dispel-Scar Ointment in Scar Treatment.

Dispel-Scar Ointment is used in Traditional Chinese Medicine to treat scarred tissue and increasing evidence has shown that DSO has potent therapeutic; however, its exact mechanism remains unexplored. This study explored the molecular mechanisms of action of DSO in scarring using network pharmacology, molecular docking, and experimental validation. Public databases were used to predict the bioactive ingredients and putative targets of DSO against scars. A compounds-targets network was constructed using the Cytoscape software. Enrichment analysis was performed using ClueGo and FunRich to specify the biological functions and associated pathways of hub targets. Molecular docking was used to verify the correlation between the major active components and hub targets, visualised using PyMol 2.3. Experimental validations were conducted to elucidate the influence of DSO on keloid fibroblast cells using the CCK-8, wound-scratch, cell reactive oxygen species, and western blot assays. Results：Network pharmacological analysis of DSO for scar treatment identified 146 ingredients and 1078 gene targets. Major targets included, prostaglandin-endoperoxide synthase 2 matrix metallopeptidases, and nitric oxide synthase 2. ClueGo analysis revealed 29 pathways (p<0.05) and FunRich 345 pathways (p<0.05), mainly toll-like receptor, TGF-β, interleukin-4/13, glypican, and tumour necrosis factor-related apoptosis-inducing ligand pathways. Molecular docking showed MMP2-flavoxanthin, MMP9-luteolin and MMP-9-kaempferol bound best to DSO. DSO could inhibit the proliferation and migration of scar fibroblasts and promote their apoptosis in a concentration-dependent manner. DSO also decreased TGF-β1, -βR2, pSMAD2, pSMAD3, SMAD4, CoL1a1, and MMP2 expression. Network pharmacology, molecular docking, and experimental validation showed DSO's potential in treating scars. It may inhibit scars via the TGF-β1/SMADs/MMPs signalling pathway, providing a basis for DSO's scar treatment application.

Talabostat, fibroblast activation protein inhibitor, attenuates inflammation and fibrosis in systemic sclerosis.

Systemic sclerosis (SSc) is a connective tissue disorder characterized by excessive fibrosis, where activated fibroblasts play a pivotal role in disease progression. This study aimed to investigate the potential of Talabostat, a small molecule inhibitor of dipeptidyl peptidases, in alleviating fibrosis and inflammation associated with SSc pathogenesis. Dermal fibroblasts were obtained from skin biopsies of ten diffuse cutaneous SSc patients and healthy controls. These fibroblasts were subjected to treatment with either TGF-β alone or in combination with Talabostat. Immunofluorescence staining was conducted to evaluate FAPα and α-SMA protein levels. The expression of activated fibroblast markers (FAPα and ACAT2), pro-fibrotic (COL1A1 and COL1A2), anti-fibrotic (MMP1, MMP2, and MMP9), and inflammatory (IL-6 and TGFβ1) related genes was measured by quantitative real-time PCR. Talabostat-treated fibroblasts were assessed for their migratory capacity using a scratch assay and for their viability through MTT assay and Annexin V staining. The basal expression of COL1A1 and TGFβ1 was notably higher in healthy subjects, while MMP1 expression showed a significant increase in SSc patients. Furthermore, TGF-β stimulation led to upregulation of activated fibroblast markers, pro-fibrotic, and inflammatory-related genes in SSc-derived fibroblasts, which were attenuated upon Talabostat treatment. Interestingly, Talabostat treatment resulted in an upregulation of MMP9 expression. Moreover, Talabostat exhibited a concentration-dependent inhibition of activated fibroblast viability in both healthy and SSc fibroblasts, and suppressed fibroblast migration specifically in SSc patients. In summary, Talabostat modulates fibrotic genes in SSc, thereby inhibiting myofibroblast differentiation, activation, and migration. These findings suggest promising therapeutic avenues for targeting fibrosis in SSc.

Inhibition of MMP2 activity mitigates N-omega-nitro-l-arginine-methyl ester (l-NAME)-induced right heart failure

In rats decreased bioavailability of nitric oxide induces oxidative stress and right heart failure. Oxidative stress can activate matrix metalloproteinase-2 (MMP2). We addressed the question whether increasing oxidative defense by administration of the SOD mimetic Tempol or direct inhibition of MMP2 activity by SB-3CT mitigates right heart failure. Rats received l-NAME for four weeks and during week three and four treatment groups received either Tempol or SB-3CT in addition. After four weeks heart function was analyzed by echocardiography, organ weights and expression of NPPB and COL1A1 were analyzed, oxidative stress was monitored by DHE-staining and MMP2 activity was quantified by proteolytic auto-activation, zymography, and troponin I degradation. l-NAME induced oxidative stress and MMP2 activity stronger in the right ventricle than in the left ventricle. Troponin I, a MMP2 substrate, was degraded in right ventricles. Tempol reduced oxidative stress and preferentially affected the expression of fibrotic genes (i.e. COL1A1) and fibrosis. Tempol and SB-3CT mitigated right but not left ventricular hypertrophy. Neither SB-3CT nor Tempol alone strongly improved right ventricular function. In conclusion, both MMP2 activity and oxidative stress contribute to right ventricular failure but neither is MMP2 activation linked to oxidative stress nor does oxidative stress and MMP2 activity have common targets.

Disulfidptosis signature predicts immune microenvironment and prognosis of gastric cancer

BackgroundDisulfidptosis is a newly identified mechanism of cell death triggered by disulfide stress. Thus, gaining a comprehensive understanding of the disulfidptosis signature present in gastric cancer (GC) could greatly enhance the development of personalized treatment strategies for this disease.MethodsWe employed consensus clustering to identify various subtypes of disulfidptosis and examined the distinct tumor microenvironment (TME) associated with each subtype. The Disulfidptosis (Dis) score was used to quantify the subtype of disulfidptosis in each patient. Subsequently, we assessed the predictive value of Dis score in terms of GC prognosis and immune efficacy. Finally, we conducted in vitro experiments to explore the impact of Collagen X (COL10A1) on the progression of GC.ResultsTwo disulfidptosis-associated molecular subtypes (Discluster A and B) were identified, each with distinct prognosis, tumor microenvironment (TME), immune cell infiltration, and biological pathways. Discluster A, characterized by high expression of disulfidptosis genes, exhibited a high immune score but poor prognosis. Furthermore, the Dis score proved useful in predicting the prognosis and immune response in GC patients. Those in the low Dis score group showed better prognosis and increased sensitivity to immunotherapy. Finally, our experimental findings validated that downregulation of COL10A1 expression attenuates the proliferation and migration capabilities of GC cells while promoting apoptosis.ConclusionsThis study demonstrates that the disulfidptosis signature can assist in risk stratification and personalized treatment for patients with GC. The results offer valuable theoretical support for anti-tumor strategies.

Spatial multiomics reveals a subpopulation of fibroblasts associated with cancer stemness in human hepatocellular carcinoma

BackgroundCancer-associated fibroblasts (CAFs) are the prominent cell type in the tumor microenvironment (TME), and CAF subsets have been identified in various tumors. However, how CAFs spatially coordinate other cell populations within the liver TME to promote cancer progression remains unclear.MethodsWe combined multi-region proteomics (6 patients, 24 samples), 10X Genomics Visium spatial transcriptomics (11 patients, 25 samples), and multiplexed imaging (92 patients, 264 samples) technologies to decipher the expression heterogeneity, functional diversity, spatial distribution, colocalization, and interaction of fibroblasts. The newly identified CAF subpopulation was validated by cells isolated from 5 liver cancer patients and in vitro functional assays.ResultsWe identified a liver CAF subpopulation, marked by the expression of COL1A2, COL4A1, COL4A2, CTGF, and FSTL1, and named F5-CAF. F5-CAF is preferentially located within and around tumor nests and colocalizes with cancer cells with higher stemness in hepatocellular carcinoma (HCC). Multiplexed staining of 92 patients and the bulk transcriptome of 371 patients demonstrated that the abundance of F5-CAFs in HCC was associated with a worse prognosis. Further in vitro experiments showed that F5-CAFs isolated from liver cancer patients can promote the proliferation and stemness of HCC cells.ConclusionsWe identified a CAF subpopulation F5-CAF in liver cancer, which is associated with cancer stemness and unfavorable prognosis. Our results provide potential mechanisms by which the CAF subset in the TME promotes the development of liver cancer by supporting the survival of cancer stem cells.

Experimental mouse model of pulmonary fibrosis induced by nebulized LPS administration

Lipopolysaccharide (LPS)-induced lung injury is the most commonly used mouse model of acute lung inflammation that simulates the development of respiratory distress syndrome in humans. The effects of acute LPS-induced airway inflammation are well studied and associated with the neutrophil accumulation in bronchoalveolar lavage fluid (BALF), local and systemic production of proinflammatory cytokines and narrowing of the airways. Recent studies demonstrated the presence of pulmonary fibrosis characterized by increased fibroblast proliferation and excess extracellular matrix deposition in late phase of acute lung inflammation caused by LPS exposure. This work describes an experimental model of acute lung injury induced by a single aerosol injection of LPS as a reproducible in vivo model of pulmonary fibrosis. To induce lung injury, C57BL/6 mice were placed in a chamber and exposed to an aerosol containing 10 mg of LPS using an Aeroneb Lab Nebulizer delivery system. We found that 5 weeks after a single nebulized LPS administration, mice have increased production of IL-6 in BALF. Although the frequency of neutrophils was not altered, there was a decrease in the percentage of alveolar macrophages at 5 weeks after LPS exposure, indicating continued lung inflammation. Several weeks after aerosolized LPS challenge, IL-10 production in BALF was increased, as well as expression of Tgfb1, Col1a1, Il13 and Acta2, and collagen deposition in lung tissue compared to mice with acute lung inflammation. Thus, the single nebulized LPS administration represents a relevant, reproducible and physiologic model in mice allowing to investigate the mechanisms of pulmonary fibrosis development and help in the search for new therapeutic agents and approaches.

Effects of vitamin D status on cutaneous wound healing through modulation of EMT and ECM

To investigate the effects of vitamin D status on cutaneous wound healing, C57BL/6J mice were fed diets with different vitamin D levels or injected intraperitoneally with 1α,25(OH)2D3. Dorsal skin wounds were created and wound edge tissues were collected on days 4, 7, 11, and 14 postwounding. The proliferation and migration of HaCaT cells treated with shVDR or 1α,25(OH)2D3 were assessed. Vitamin D deficiency (VDD) decreased wound closure and might delay inflammatory response, shown by slower inflammatory cell infiltration, decreased IL6 and TNF expression in early phase followed by an increase later. VDD might postpone epithelial-mesenchymal transition (EMT), initially characterized by higher epithelial markers and lower mesenchymal markers, followed by opposite appearance later. Dietary vitamin D supplementation and 1α,25(OH)2D3 intervention tended to accelerate EMT. Regarding extracellular matrix (ECM), VDD appeared to reduce collagen deposition on day 4 and downregulated fibronectin, COL3A1, and MMP9 expression early, followed by an increase later, together with an initial increase and subsequent decrease in Timp1 mRNA expression. Dietary vitamin D intervention promoted fibronectin and MMP9 expression on day 4 and then downregulated their expression on day 14. TGFb1/SMAD2/3 signaling seemed to be downregulated by VDD and upregulated by 1α,25(OH)2D3. In vitro, partial inhibition of VDR by shVDR tended to inhibit HaCaT cell proliferation and migration, EMT, and TGFb1/SMAD2/3 signaling, whereas 1α,25(OH)2D3 appeared to generate opposite effects. In conclusion, VDD hindered cutaneous wound healing, potentially due to impaired inflammatory response, delayed EMT, decreased ECM, and inhibited TGFb1/SMAD2/3 pathway. Vitamin D and 1α,25(OH)2D3 tended to enhance EMT and ECM.

Identification of COL3A1 as a candidate protein involved in the crosstalk between obesity and diarrhea using quantitative proteomics and machine learning

BackgroundIncreasing epidemiologic studies have shown a positive correlation between obesity and chronic diarrhea. Nevertheless, the precise etiology remains uncertain. MethodsWe performed a comprehensive proteomics analysis utilizing the data-independent acquisition (DIA) technique on jejunal tissues from patients with obesity and chronic diarrhea (OD, n = 33), obese patients (OB, n = 10), and healthy controls (n = 8). Differentially expressed proteins (DEPs) in OD vs. control and OD vs. OB comparisons were subjected to pathway enrichment and protein-protein interaction (PPI) network analysis. Machine learning algorithms were adopted on overlapping DEPs in both comparisons. The candidate protein was further validated using Western blot, immunohistochemistry (IHC), and in vitro experiments. ResultsWe identified 189 and 228 DEPs in OD vs. control and OD vs. OB comparisons, respectively. DEPs in both comparisons were co-enriched in extracellular matrix (ECM) organization. Downregulated DEPs were associated with tight junction and ECM-receptor interaction in OD vs. control and OD vs. OB comparisons, respectively. Machine learning algorithms selected 3 proteins from 14 overlapping DEPs in both comparisons, among which collagen alpha-1(III) chain (COL3A1) was identified as a core protein in PPI networks. Western blot and IHC verified the expression of COL3A1. Moreover, the tight junction-related proteins decreased after the knockdown of COL3A1 in Caco2 intestinal cells upon PA challenge, consistent with the proteomics results. ConclusionsWe generated in-depth profiling of a proteomic dataset from samples of OD patients and provided unique insights into disease pathogenesis. COL3A1 was involved in the crosstalk between obesity and intestinal homeostasis via the ECM-receptor interaction pathway.

Eosinophil Depletion as a Potential Therapeutic Strategy in Acute and Chronic Intestinal Inflammation Based on a Dextran Sulfate Sodium Colitis Model.

A role for eosinophils in intestinal inflammation and fibrosis in the context of inflammatory bowel disease has been suggested, yet the precise nature, whether causal or secondary remains debated. Hence, it remains unclear whether targeting eosinophils should be further explored as a treatment option in inflammatory bowel disease. Acute and chronic dextran sulfate sodium colitis was induced in wild-type C57BL/6 mice. Eosinophils were depleted by anti-CCR3 injections before colitis induction in a chronic model and after colitis onset in an acute model in order to investigate the impact of eosinophil depletion on pre-existing colitis. Inflammation was assessed using the disease activity index, macroscopic damage, and histological disease activity score. In the chronic model, fibrosis was assessed by examining colon weight/length ratio, collagen deposition through Martius Scarlet Blue staining, hydroxyproline assay, and COL1A1 expression. Protein and gene expression were assessed using the Meso Scale Discovery platform and real-time quantitative polymerase chain reaction. In the acute and chronic colitis model, eosinophil depletion resulted in reduced disease activity and faster recovery, as observed via the total area under the curve of the disease activity index (P = .004 and P = .02, respectively), macroscopic damage score (P = .009 and P = .08, respectively), and histological disease activity score (P = .09 and P = .002, respectively). In the acute model, the accelerated recovery was accompanied by an increase in interleukin (IL)-10 (P = .03) and a decrease in IL-4 (P = .03) and IL-6 (P = .009). Colon weight/length ratio and collagen deposition were not affected by eosinophil depletion. Eosinophil depletion prevents and decreases intestinal inflammation in a preclinical dextran sulfate sodium model without affecting fibrosis. These results pave the way for exploring eosinophil depletion as a novel treatment modality in addressing intestinal inflammation.

Effect of electrical muscle stimulation on the improvement of deltoid muscle atrophy in a rat shoulder immobilization model.

Immobilization following trauma or surgery induces skeletal muscle atrophy, and improvement in the muscle atrophy is critical for successful clinical outcomes. The purpose of this study is to evaluate the effect of electrical muscle stimulation (EMS) on muscle atrophy. The study design is a controlled laboratory study. Eighty rats (56 to establish the deltoid muscle atrophy [DMA] model and 24 to evaluate the effect of EMS on the model) were used. DMA was induced by completely immobilizing the right shoulder of each rat by placing sutures between the scapula and humeral shaft, with the left shoulder as a control. After establishing the DMA model, rats were randomly assigned into three groups: low-frequency EMS (L-EMS, 10 Hz frequency), medium-frequency EMS (M-EMS, 50 Hz frequency), and control (eight rats per group). After 3 weeks, the deltoid muscles of each rat were harvested, alterations in gene expression and muscle cell size were evaluated, and immunohistochemical analysis was performed. DMA was most prominent 3 weeks after shoulder immobilization. Murf1 and Atrogin were significantly induced at the initial phase and gradually decreased at approximately 3 weeks; however, MyoD expressed an inverse relationship with Murf1 and Atrogin. IL6 expression was prominent at 1 week. The time point for the EMS effect evaluation was selected at 3 weeks, when the DMA was the most prominent with a change in relevant gene expression. The M-EMS group cell size was significantly larger than that of L-EMS and control group in both the immobilized and intact shoulders (all p < 0.05), without significant differences between the L-EMS and control groups. The M-EMS group showed significantly lower mRNA expressions of Murf1 and Atrogin and higher expressions of MyoD and Col1A1 than that of the control group (all p < 0.05). In immunohistochemical analysis, similar results were observed with lower Atrogin staining and higher MyoD and Col1A1 staining in the M-EMS group. DMA model was established by complete shoulder immobilization, with the most prominent muscle atrophy observed at 3 weeks. M-EMS improved DMA with changes in the expression of relevant genes. M-EMS might be a solution for strengthening atrophied skeletal muscles and facilitating rehabilitation after trauma or surgery.

L-Carnitine relieves cachexia-related skeletal muscle fibrosis by inducing deltex E3 ubiquitin ligase 3L to negatively regulate the Runx2/COL1A1 axis.

Cancer cachexia-induced skeletal muscle fibrosis (SMF) impairs muscle regeneration, alters the muscle structure and function, reduces the efficacy of anticancer drugs, diminishes the patient's quality of life and shortens overall survival. RUNX family transcription factor 2 (Runx2), a transcription factor, and collagen type I alpha 1 chain (COL1A1), the principal constituent of SMF, have been linked previously, with Runx2 shown to directly modulate COL1A1 mRNA levels. l-Carnitine, a marker of cancer cachexia, can alleviate fibrosis in liver and kidney models; however, its role in cancer cachexia-associated fibrosis and the involvement of Runx2 in the process remain unexplored. Female C57 mice (48weeks old) were inoculated subcutaneously with MC38 cells to establish a cancer cachexia model. A 5mg/kg dose of l-carnitine or an equivalent volume of water was administered for 14days via oral gavage, followed by assessments of muscle function (grip strength) and fibrosis. To elucidate the interplay between the deltex E3 ubiquitin ligase 3L(DTX3L)/Runx2/COL1A1 axis and fibrosis in transforming growth factor beta 1-stimulated NIH/3T3 cells, a suite of molecular techniques, including quantitative real-time PCR, western blot analysis, co-immunoprecipitation, molecular docking, immunofluorescence and Duolink assays, were used. The relevance of the DTX3L/Runx2/COL1A1 axis in the gastrocnemius was also explored in the in vivo model. l-Carnitine supplementation reduced cancer cachexia-induced declines in grip strength (>88.2%, P<0.05) and the collagen fibre area within the gastrocnemius (>57.9%, P<0.05). At the 5mg/kg dose, l-carnitine also suppressed COL1A1 and alpha-smooth muscle actin (α-SMA) protein expression, which are markers of SMF and myofibroblasts. Analyses of the TRRUST database indicated that Runx2 regulates both COL1A1 and COL1A2. In vitro, l-carnitine diminished Runx2 protein levels and promoted its ubiquitination. Overexpression of Runx2 abolished the effects of l-carnitine on COL1A1 and α-SMA. Co-immunoprecipitation, molecular docking, immunofluorescence and Duolink assays confirmed an interaction between DTX3L and Runx2, with l-carnitine enhancing this interaction to promote Runx2 ubiquitination. l-Carnitine supplementation restored DTX3L levels to those observed under non-cachectic conditions, both in vitro and in vivo. Knockdown of DTX3L abolished the effects of l-carnitine on Runx2, COL1A1 and α-SMA in vitro. The expression of DTX3L was negatively correlated with the levels of Runx2 and COL1A1 in untreated NIH/3T3 cells. This study revealed a previously unrecognized link between Runx2 and DTX3L in SMF and demonstrated that l-carnitine exerted a significant therapeutic impact on cancer cachexia-associated SMF, potentially through the upregulation of DTX3L.

The differences between sinonasal respiratory epithelial adenomatoid hamartoma and nasal polyps: insights into immunopathology.

Respiratory epithelial adenomatoid hamartoma (REAH) is a benign lesion commonly occurring in the nasal cavity and sinuses. It is often accompanied by nasal polyps (NP). While the histological features of these two conditions have been studied, there is limited knowledge about their differences in the underlying immunopathology. Nasal tissue specimens were collected from 8 patients with concurrent REAH and NP and 10 controls. The expression levels of inflammatory cytokines, tight junctions (TJ), and epithelial-mesenchymal transition (EMT)-related factors in the tissues were analyzed. The mRNA expression of the aforementioned factors was measured using qRT-PCR, while the expression of TJ and EMT-related proteins was analyzed through Western blotting and immunohistochemistry. Compared to the control group, levels of inflammatory cytokines (IFN-α, IL-5, IL-17A, IL-31, IL-33, and TNF-α) and EMT-related factors (α-SMA, COL1A1, MMP9, TGF-β1, and Vimentin) were significantly increased in both REAH and NP tissues. Conversely, E-Cadherin and TJ-related factors (Claudin-4 and Occludin) significantly decreased. When comparing REAH with NP, it was observed that the expression of IL-4, IL-5, and IL-33 was lower in REAH, while TNF-ɑ; was higher. Regarding TJ-related factors, the expression of Occludin was lower in REAH. Furthermore, in terms of EMT-related factors, except for E-Cadherin, the expressions of ɑ-SMA, COL1A1, CTGF, MMP9, TGF-β11, and Vimentin were higher in REAH. REAH and NP exhibit different immunopathological mechanisms. NP demonstrates a more severe inflammatory response, whereas REAH is characterized by a more pronounced TJ and EMT breakdown than NP.

Development of polyvinyl alcohol nanofiber scaffolds loaded with flaxseed extract for bone regeneration: phytochemicals, cell proliferation, adhesion, and osteogenic gene expression.

Introduction: Bone tissue engineering seeks innovative materials that support cell growth and regeneration. Electrospun nanofibers, with their high surface area and tunable properties, serve as promising scaffolds. This study explores the incorporation of flaxseed extract, rich in polyphenolic compounds, into polyvinyl alcohol (PVA) nanofibers to improve their application in bone tissue engineering. Methods: High-performance liquid chromatography (HPLC) identified ten key compounds in flaxseed extract, including polyphenolic acids and flavonoids. PVA nanofibers were fabricated with 30 wt.% flaxseed extract (P70/E30) via electrospinning. We optimized characteristics like diameter, hydrophilicity, swelling behavior, and hydrolytic degradation. MG-63 osteoblast cultures were used to assess scaffold efficacy through cell adhesion, proliferation, viability (MTT assay), and differentiation. RT-qPCR measured expression of osteogenic genes RUNX2, COL1A1, and OCN. Results: Flaxseed extract increased nanofiber diameter from 252nm (pure PVA) to 435nm (P70/E30). P70/E30 nanofibers showed higher cell viability (102.6% vs. 74.5% for pure PVA), although adhesion decreased (151 vs. 206 cells/section). Notably, P70/E30 enhanced osteoblast differentiation, significantly upregulating RUNX2, COL1A1, and OCN genes. Discussion: Flaxseed extract incorporation into PVA nanofibers enhances bone tissue engineering by boosting osteoblast proliferation and differentiation, despite reduced adhesion. These properties suggest P70/E30's potential for regenerative medicine, emphasizing scaffold optimization for biomedical applications.