Efficacy of tibial cortex transverse transport in treating diabetic foot ulcer and its effect on serum omentin-1 and irisin levels.

OBJECTIVE: Diabetic foot ulcer (DFU) is a common and debilitating complication of diabetes that is associated with an increased risk of lower-limb amputation and a reduced life expectancy. Tibial cortex transverse transport (TTT) has become a newly alternative surgical method to facilitate ulcer healing and prevent lower limb amputation. Herein, we investigated the efficacy of TTT in treating DFU and changes of serum omentin-1 and irisin levels. METHODS: This study prospectively recruited 52 consecutive patients with DFU who were treated with TTT. The follow-up was performed weekly during the first 12 weeks postoperatively and every 3 months until 1 year after TTT. The serum levels of vascular endothelial growth factor (VEGF), omentin-1, and irisin in DFU patients undergoing TTT were determined by ELISA methods on the preoperative 1st day, postoperative 2nd week and 4th week. RESULTS: The wound healing rate was 92.3% (48/52) at the 1-year follow-up. The visual analog scale (VAS) pain scores of patients showed a significant reduction at the 4th week after TTT (p < 0.001). The dorsal foot skin temperature, ankle brachial index, and dorsal foot blood flow of patients were significantly increased at the 4th week after TTT (p < 0.001). Results of ELISA methods showed the serum levels of VEGF, omentin-1, and irisin on the 2nd week and 4th week after TTT were notably elevated compared to the levels determined on the preoperative 1st day (p < 0.001). The serum levels of VEGF, omentin-1, and irisin on the 4th week after TTT were also significantly higher than the levels determined on the 2nd week after TTT (p < 0.001). CONCLUSION: TTT could promote the wound healing and reduce the risk of lower limb amputation, demonstrating promising clinical benefits in the treatment of DFU. Increased expressions of serum proangiogenic factors including VEGF, omentin-1, and irisin were noted in the early stage after TTT, which may provide a new mechanism of TTT promoting wound heal.

Relationship between serum Midkine and Omentin-1 levels and the severity of sepsis in patients and their prognostic value.

To explore the relationship between serum levels of midkine and omentin-1 and the severity of sepsis in patients, and their prognostic value. A retrospective analysis was conducted on the clinical data of 180 sepsis patients. According to the severity of the patient's condition, they were separated into sepsis group (n = 76), severe sepsis group (n = 59), and sepsis shock group (n = 45). Based on the survival within 28 days of admission, they were grouped into survivors group (n = 128) and nonsurvivors group (n = 52). The serum Midkine level and APACHE II score in the sepsis shock group were higher than those in the severe sepsis group and sepsis group, while the Omentin-1 level was lower than that in the severe sepsis group and sepsis group (p < 0.05). The serum Midkine level and APACHE II score in the severe sepsis group were higher than those in the sepsis group, while the Omentin-1 level was lower than that in the sepsis group (p < 0.05). The Midkine and APACHE II score in the nonsurvivors group was higher than those in the survivors group, while the Omentin-1 score was lower than that in the survivors group (p < 0.05). Midkine and APACHE II score were independent risk factors for the prognosis of sepsis patients, while Omentin-1 was a protective factor for the prognosis of sepsis patients (p < 0.05). The AUC of the combined prediction of serum Midkine and Ommentin-1 for the prognosis of sepsis patients was 0.880, with a sensitivity of 90.38% and a specificity of 72.66%. The combined prediction of serum Midkine and Ommentin-1 was better than that of individual prediction of Midkine and Ommentin-1. Serum Midkine is highly expressed and Omentin-1 is lowly expressed in sepsis patients, and the combination of the two has a high predictive power for the prognosis of sepsis patients.

The role of adipokines in the pathogenesis of psoriasis - a focus on resistin, omentin-1 and vaspin.

BACKGROUND: Psoriasis is a chronic immune-mediated skin condition with several types of manifestation, including psoriatic arthritis. In recent years, studies have demonstrated multiple molecules and mechanisms that play important roles in the pathophysiology of psoriasis. Studies have been conducted to determine the role of adipokines, bioactive peptides secreted by the adipose tissue, in the pathogenesis of inflammatory diseases. These studies have shown that adipokines are dysregulated in psoriasis and their abnormal expression profile could contribute to the inflammatory mechanisms observed in psoriasis. AREAS COVERED: In this review, we discuss the immunomodulatory features of resistin, omentin-1, and vaspin, and discuss their potential involvement in the pathogenesis of psoriasis. EXPERT OPINION: The adipokines resistin, omentin, and vaspin appear to be promising therapeutic targets in psoriasis. It is important to seek to block the action of resistin, either by blocking its receptors or by blocking its systemic effects with antibodies. In the case of omentin and vaspin, substances that are receptor mimetics of these adipokines should be sought and studies conducted of their analogues for the treatment of psoriasis. To introduce these therapies into clinical practice, multicentre clinical trials are required to confirm their efficacy and safety after initial studies in animal models.

Omentin-1 inhibits the development of benign prostatic hyperplasia by attenuating local inflammation.

BACKGROUND: Benign prostatic hyperplasia (BPH) is a prevalent disease affecting elderly men, with chronic inflammation being a critical factor in its development. Omentin-1, also known as intelectin-1 (ITLN-1), is an anti-inflammatory protein primarily found in the epithelial cells of the small intestine. This study aimed to investigate the potential of ITLN-1 in mitigating BPH by modulating local inflammation in the prostate gland. METHODS: Our investigation involved two in vivo experimental models. Firstly, ITLN-1 knockout mice (Itln-1-/-) were used to study the absence of ITLN-1 in BPH development. Secondly, a testosterone propionate (TP)-induced BPH mouse model was treated with an ITLN-1 overexpressing adenovirus. We assessed BPH severity using prostate weight index and histological analysis, including H&E staining, immunohistochemistry, and enzyme-linked immunosorbent assay. In vitro, the impact of ITLN-1 on BPH-1 cell proliferation and inflammatory response was evaluated using cell proliferation assays and enzyme-linked immunosorbent assay. RESULTS: In vivo, Itln-1-/- mice exhibited elevated prostate weight index, enlarged lumen area, and higher TNF-α levels compared to wild-type littermates. In contrast, ITLN-1 overexpression in TP-induced BPH mice resulted in reduced prostate weight index, lumen area, and TNF-α levels. In vitro studies indicated that ITLN-1 suppressed the proliferation of prostate epithelial cells and reduced TNF-α production in macrophages, suggesting a mechanism involving the inhibition of macrophage-mediated inflammation. CONCLUSION: The study demonstrates that ITLN-1 plays a significant role in inhibiting the development of BPH by reducing local inflammation in the prostate gland. These findings highlight the potential of ITLN-1 as a therapeutic target in the management of BPH.

Omentin-1 ameliorates pulmonary arterial hypertension by inhibiting endoplasmic reticulum stress through AMPKα signaling.

BACKGROUND: Endothelial dysfunction of the pulmonary artery contributes to hypoxia-induced pulmonary arterial hypertension (PAH). Omentin-1, as a novel adipocytokine, plays an important protective role against cardiovascular diseases. However, the effect and underlying mechanisms of omentin-1 against PAH remain unclear. METHODS: PAH was induced in SD (Sprague & Dawley) rats via a low-oxygen chamber for 4 weeks. Hemodynamic evaluation was undertaken using a PowerLab data acquisition system, and histopathological analysis was stained with hematoxylin and eosin (H&E). Endothelial function of pulmonary artery was assessed using wire myography. RESULTS: We found that omentin-1 significantly improved pulmonary endothelial function in rats exposed to hypoxia and attenuated PAH. Mechanistically, we found that omentin-1 increased phosphorylated 5'­adenosine monophosphate­activated protein kinase (p­AMPK) level and reduced endoplasmic reticulum (ER) stress and increased NO production in pulmonary artery from rats exposed to hypoxia. However, the effect of omentin-1 was abolished by treatment with AMPK inhibitor (Compound C). CONCLUSIONS: Our results reveal a protective effect of omentin-1 in PAH via inhibiting ER stress through AMPKα signaling and provide an agent with translational potential for the treatment of PAH.

Expression of TNF-α, omentin-1, and IL-6 before and after adjunctive treatment with a bioactive antimicrobial peptide periodontal gel.

BACKGROUND: The objective of this study was to evaluate and compare the expression levels of TNF-α, omentin-1, and IL-6 in periodontitis patients before and after treatment with biological antimicrobial peptide (AMP) periodontal gel. METHODS: There involved 86 periodontitis patients admitted to our hospital from January 2020 to March 2021. They were equally and randomly distributed into the study group and the control group. The efficacy and adverse reactions were compared between the two groups after treatment, Additionally, the sulcus bleeding index (SBI), plaque index (PLI), gingival index (GI), periodontal probing depth (PD), and levels of TNF-α, omentin-1, and IL-6 were measured before and after treatment. RESULTS: After treatment, the total effective rate of the study group was significantly higher than that of the control group (p < 0.05), while the scores of four indicators (SBI, PLI, GI, and PD) and the levels of TNF-α, omentin-1, and IL-6 in the study group were evidently lower than the control group (p < 0.05). The study group had 1 case of mild irritant reaction, with an adverse reaction rate of 2.33% (1/43). And the control group had 1 case of nausea and 1 case of allergy, with an adverse reaction rate of 4.65% (2/43). The adverse reactions demonstrated no statistical difference between the two groups (χ2 = 0.345, p = 0.557). CONCLUSIONS: The levels of TNF-α and IL-6 were highly expressed before the auxiliary therapy of biological AMP periodontal gel for periodontitis, alongside low expression of omentin-1. Subsequently, the biological antibacterial polypeptide periodontal gel demonstrated efficacy in the treatment of periodontitis.

Association between serum omentin-1 and mucosal disease activity in patients with ulcerative colitis.

PURPOSE: Mucosal inflammation is a key feature of ulcerative colitis (UC), a chronic relapsing and remitting form of inflammatory bowel disease. Omentin-1, a newly discovered adipokine, is reported to have anti-inflammatory effects and has been found to be decreased in patients with inflammatory bowel disease. The aim of our study was to investigate the association between serum omentin-1 levels and mucosal disease activity in patients with UC. STUDY DESIGN: A total of 126 patients with UC and 77 healthy volunteers were enrolled in the study. Serum omentin-1 expression levels were measured using enzyme-linked immunosorbent assay to evaluate its potential for monitoring disease activity, including clinical and endoscopic activity. RESULTS: Serum omentin-1 levels were significantly lower in patients with UC compared to healthy controls (HC) (UC, 61.7 interquartile range: 51.5-72.6 versus healthy controls, 103.5 interquartile range: 48.3-156.2 ng/ml; P < .001). Furthermore, serum omentin-1 levels were associated with both clinical and endoscopic activity in patients with UC. Notably, omentin-1 levels were significantly lower in patients who achieved mucosal healing. Receiver operating characteristic curves indicated that serum omentin-1 levels could potentially serve as an activity index for evaluating UC. CONCLUSIONS: These findings provide further insight into the association between omentin-1 and UC, suggesting that omentin-1 may be a useful biomarker for monitoring mucosal disease activity in patients with UC.

Effect of Exercise Training on Some Anti-Inflammatory Adipokines, High Sensitivity C-Reactive Protein, and Clinical Outcomes in Sedentary Adults With Metabolic Syndrome.

OBJECTIVE: This study aimed to investigate the effects of aerobic interval training and resistance training on anti-inflammatory adipokines, high sensitivity C-reactive protein, and clinical outcomes in sedentary men with metabolic syndrome. METHODS: A total of 33 sedentary men with metabolic syndrome (age: 46.2 ± 4.6 years; body mass index: 35.4 ± 1.9 kg.m2) were randomly assigned to one of 3 groups: aerobic interval training (n = 12), resistance training (n = 10), or control (n = 11). Participants in the exercise groups completed a 12-week training program, 3 sessions per week, while those in the control group maintained their sedentary lifestyle. The levels of high sensitivity C-reactive protein (hs-CRP), omentin-1, adiponectin, lipid profiles, blood pressure, glucose metabolism, body composition, and peak oxygen uptake (VO2peak) were measured at baseline and after the intervention. RESULTS: Both aerobic interval training and resistance training significantly improved the levels of omentin-1 and adiponectin, as well as reduced inflammation, as indicated by a decrease in hs-CRP levels. Exercise training also led to significant improvements in lipid profiles, blood pressure, glucose metabolism, and body composition. Specifically, the aerobic interval training group had significantly greater increases in high-density lipoprotein cholesterol and VO2peak, as well as greater reductions in low-density lipoprotein cholesterol, triglycerides, and total cholesterol compared to the resistance training group. CONCLUSION: Exercise training, particularly aerobic interval training and resistance training, can be an effective non-pharmacological intervention for managing inflammation and improving cardiovascular health in metabolic syndrome patients.

The potential role of omentin-1 in obesity-related metabolic dysfunction-associated steatotic liver disease: evidence from translational studies.

BACKGROUND: Obesity, characterized by visceral adipose tissue (VAT) expansion, is closely associated with metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH). Recent research has highlighted the crucial role of the adipose tissue-liver axis in the development of MASLD. In this study, we investigated the potential role of omentin-1, a novel adipokine expressed by VAT, in obesity-related MASLD pathogenesis. METHODS: Through in silico analysis of differentially expressed genes in VAT from obese patients with and without MASH, we identified omentin-1 as a significant candidate. To validate our findings, we measured omentin-1 levels in VAT and plasma of lean controls and obese patients with biopsy-proven MASLD. Additionally, we assessed omentin-1 expression in the VAT of diet-induced mice MASLD model. In vitro and ex vivo studies were conducted to investigate the effects of omentin-1 on MASLD-related mechanisms, including steatosis, inflammation, endoplasmic reticulum (ER) stress, and oxidative stress. We also analyzed the impact of D-glucose and insulin on VAT omentin-1 levels ex vivo. RESULTS: Compared to the lean group, the obese groups exhibited significantly lower VAT and plasma levels of omentin-1. Interestingly, within the obese groups, omentin-1 is further decreased in MASH groups, independent of fibrosis. Likewise, VAT of mice fed with high-fat diet, showing histological signs of MASH showed decreased omentin-1 levels as compared to their control diet counterpart. In vitro experiments on fat-laden human hepatocytes revealed that omentin-1 did not affect steatosis but significantly reduced TNF-α levels, ER stress, and oxidative stress. Similar results were obtained using ex vivo VAT explants from obese patients upon omentin-1 supplementation. Furthermore, omentin-1 decreased the mRNA expression of NF-κB and mitogen-activated protein kinases (ERK and JNK). Ex vivo VAT explants showed that D-glucose and insulin significantly reduced omentin-1 mRNA expression and protein levels. CONCLUSIONS: Collectively, our findings suggest that reduced omentin-1 levels contribute to the development of MASLD. Omentin-1 supplementation likely exerts its beneficial effects through the inhibition of the NF-κB and MAPK signaling pathways, and it may additionally play a role in the regulation of glucose and insulin metabolism. Further research is warranted to explore omentin-1 as a potential therapeutic target and/or biomarker for MASLD.

Evaluation of serum adipokines (omentin-1 and visfatin) in coronary artery disease at a North Indian hospital.

Objective. Adipose tissue is considered to be an endocrine organ that secretes bioactive substances known as adipokines that contribute to the pathophysiology of metabolic and coronary diseases related to obesity. In this study, various novel biomarkers, such as inflammatory markers that are pro-inflammatory (visfatin) and anti-inflammatory (omentin-1), as prognostic indicators for people with coronary artery disease (CAD) were investigated. Methods. In this study, 30 diabetic patients with CAD, 30 diabetic patients without CAD, and 30 healthy control counterparts were included. Serum omentin and visfatin concentrations were evaluated by solid-phase enzyme linked immunosorbent assay (ELISA) kit. Patients with established diagnosis of CAD based on angiography, ECG, and elevated cardiac marker level were included into the study. Patients with cardioembolic stroke, cerebral venous sinus thrombosis, CNS vasculitis, and hemorrhage due to trauma, tumor, vascular malformation, and coagulopathy were excluded. Results. The serum omentin-1 levels were significantly higher in the healthy controls in comparison with the diabetic group (p<0.0001) and serum visfatin levels were significantly higher in the diabetic group in comparison with the healthy controls (p<0.0001). The serum omentin levels were significantly higher in the diabetic group in comparison with the cardio-diabetic group (p<0.0001) and serum visfatin levels were significantly higher in the cardio-diabetic group in comparison with the diabetic group (p<0.0001). The serum omentin-1 showed negative correlation with the serum visfatin in the cardio-diabetic group. Conclusion. The adipokines, such as omentin and visfatin, may be good therapeutic candidates in preventing or ameliorating CAD.

Omentin-1 ameliorates the progress of osteoarthritis by promoting IL-4-dependent anti-inflammatory responses and M2 macrophage polarization.

Osteoarthritis (OA) is a prevalent joint disease commonly associated with aging and obesity, which can lead to pain, stiffness, joint dysfunction, and disability. Omentin-1 (also called intelectin-1) is a newly discovered adipokine, which plays a protective role in suppressing the secretion of pro-inflammatory cytokines. Based on data from the Gene Expression Omnibus (GEO) dataset and clinical samples obtained at our institution revealed, determined that omentin-1 and IL-4 (an anti-inflammatory cytokine) levels were significantly lower in OA patients than in normal controls. Omentin-1 was shown to induce IL-4-depedent anti-inflammatory responses and M2 macrophage polarization in OA synovial fibroblasts via the PI3K, ERK, and AMPK pathways. Administering omentin-1 was shown to block cartilage degradation and bone erosion resulting from anterior cruciate ligament transection by inhibiting the production of pro-inflammatory cytokines and promoting M2 macrophage polarization in vivo. Our findings indicate omentin-1 as a promising therapeutic avenue for the treatment for OA.

Association between omentin-1 and heart failure with preserved ejection fraction in Chinese elderly patients.

BACKGROUND: Omentin-1 is a novel adipokine and is associated with chronic inflammation and cardiovascular diseases. However, it remains unclear whether omentin-1 levels are associated with diagnostic significance in elderly patients with heart failure with preserved ejection fraction (HFpEF). This study aimed to investigate the correlation between omentin-1 and HFpEF in Chinese elderly patients. HYPOTHESIS: Omentin-1 may be invovled in HFpEF and there may be a difference of omentin-1 levels between HFpEF and control. METHODS: 217 subjects were selected, including 115 patients with HFpEF and 102 control subjects. Enzyme-linked immuno sorbent assay (ELISA) was used to detect plasma levels of omentin-1, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). The receiver operating characteristics (ROC) curve was used to examine the diagnostic performance of omentin-1 in HFpEF. RESULTS: The levels of omentin-1 decreased significantly in the HFpEF group (14.02 ± 8.35 vs. 19.74 ± 8.45 ng/mL, p < .001), while NT-proBNP, IL-6, and TNF-α levels were significantly increased in the HFpEF group compared with the control group. Spearman correlation analysis showed that omentin-1 levels were negatively correlated with E/e' (r = -.340, p < .001). The multivariate logistic regression analysis indicated that omentin-1 was an independent protective factor for HFpEF (odd ratio = 0.948, 95% confidence interval [CI] 0.905-0.993, p = .025). Omentin-1 levels were negatively correlated with NT-proBNP (r = -.273, p < .001) and TNF-α (r = -.221, p = .001). Diagnostic efficiency by ROC curve analysis in the patients with HFpEF showed that the area under the curve (AUC) for omentin-1 was equivalent to NT-proBNP (AUC: 0.734, 95%CI 0.667-0.802; AUC: 0.800, 95%CI 0.738-0.861). Subgroup analysis showed that in the patients between the age of 70 and 80, the predictive capability of omentin-1 was stronger than NT-proBNP (AUC: 0.809, 95%CI 0.680-0.937; AUC: 0.674, 95%CI 0.514-0.833). CONCLUSIONS: Omentin-1 levels which were associated with inflammation, were decreased in the HFpEF patients. It could be regarded as a valuable biomarker for the occurrence and development of HFpEF in elderly patients.

Omentin-1 induces mechanically activated fibroblasts lipogenic differentiation through pkm2/yap/pparγ pathway to promote lung fibrosis resolution.

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal lung disease characterized by extensive extracellular matrix (ECM) deposition by activated myofibroblasts, which are specialized hyper-contractile cells that promote ECM remodeling and matrix stiffening. New insights on therapeutic strategies aimed at reversing fibrosis by targeting myofibroblast fate are showing promise in promoting fibrosis resolution. Previously, we showed that a novel adipocytokine, omentin-1, attenuated bleomycin (BLM)-induced lung fibrosis by reducing the number of myofibroblasts. Apoptosis, deactivation, and reprogramming of myofibroblasts are important processes in the resolution of fibrosis. Here we report that omentin-1 reverses established lung fibrosis by promoting mechanically activated myofibroblasts dedifferentiation into lipofibroblasts. Omentin-1 promotes myofibroblasts lipogenic differentiation by inhibiting dimerization and nuclear translocation of glycolytic enzymes pyruvate kinase isoform M2 (PKM2) and activation of the downstream Yes-associated protein (YAP) by increasing the cofactor fructose-1,6-bisphosphate (F1, 6BP, FBP). Moreover, omentin-1 activates proliferator-activated receptor gamma (PPARγ) signaling, the master regulator of lipogenesis, and promotes the upregulation of the lipogenic differentiation-related protein perilipin 2 (PLIN2) by suppressing the PKM2-YAP pathway. Ultimately, omentin-1 facilitates myofibroblasts transformation into the lipofibroblast phenotype, with reduced collagen synthesis and enhanced degradation properties, which are crucial mechanisms to clear the ECM deposition in fibrotic tissue, leading to fibrosis resolution. Our results indicate that omentin-1 targets mechanical signal accelerates fibrosis resolution and reverses established lung fibrosis by promoting myofibroblasts lipogenic differentiation, which is closely associated with ECM clearance in fibrotic tissue. These findings suggest that targeting mechanical force to promote myofibroblast lipogenic differentiation is a promising therapeutic strategy against persistent lung fibrosis.

SERUM OMENTIN-1 LEVEL IS ASSOCIATED WITH THE AGGREGATION OF CARDIOVASCULAR RISK FACTORS IN ADOLESCENTS.

Objective: The existing studies involving omentin-1 have mainly focused on relationships with single cardiovascular risk factor. Whether omentin-1 is associated with the aggregation of cardiovascular risk factors has not been reported. We investigate the relationship between the serum omentin-1 level and aggregation of cardiovascular risk factors in adolescents. Subjects and Methods: A total of 741 young students, 11-16 years of age, were enrolled using a stratified cluster sampling method. The participants were given a questionnaire survey and underwent a physical examination. The aggregation of cardiovascular risk factors was defined as two or more cardiovascular risk factors occurring simultaneously in the same individual. Results: Partial correlation analysis suggested that serum omentin-1 level was significantly correlated with waist circumference (R=-0.086, P=0.019) and Body Mass Index (R=-0.096, P=0.009). Logistic regression analysis showed that as the serum omentin-1 level increased, the risk of aggregation of cardiovascular risk factors decreased. Cardiovascular risk factors which were most closely associated with a decrease in the serum omentin-1 level were obesity calculated by Body Mass Index (OR=0.988, P=0.043) and central obesity calculated by waist circumference (OR=0.993, P=0.012). Conclusions: The serum omentin-1 level in adolescents is inversely associated with the aggregation of cardiovascular risk factors. Waist circumference and Body Mass Index are factors most closely associated with a decrease in the serum omentin-1 level.

Omentin-1 enhances the inhibitory effect of endothelial progenitor cells on neointimal hyperplasia by inhibiting the p38 MAPK/CREB pathway.

AIMS: Endothelial progenitor cells (EPCs) play an important role in vascular repair. However, they are dysfunctional in the inflammatory microenvironment during restenosis. In this study, we investigated whether omentin-1, an anti-inflammatory factor, could reduce neointima formation after carotid artery injury (CAI) in rats by improving EPC functions that were damaged by inflammation and the underlying mechanisms. MAIN METHODS: EPCs were transfected with adenoviral vectors expressing human omentin-1 or green fluorescent protein (GFP). Then, the rats received 2 × 106 EPCs expressing omentin-1 or GFP by tail vein injection directly after CAI and again 24 h later. Hematoxylin-eosin staining and immunohistochemistry were used for analyzing neointimal hyperplasia. Besides, EPCs were treated with omentin-1 and TNF-α to examine the underlying mechanism. KEY FINDINGS: Our results showed that omentin-1 could significantly improve EPC functions, including proliferation, apoptosis and tube formation. Meanwhile, EPCs overexpressed with omentin-1 could significantly reduce neointimal hyperplasia and tumor necrosis factor-α (TNF-α) expression after CAI in rats. TNF-α could notably induce EPC dysfunction, which could be markedly reversed by omentin-1 through the inhibition of the p38 MAPK/CREB pathway. Furthermore, a p38 MAPK agonist (anisomycin) significantly abrogated the protective effects of omentin-1 on EPCs damaged by TNF-α. SIGNIFICANCE: Our results indicated that genetically modifying EPC with omentin-1 could be an alternative strategy for the treatment of restenosis.

The Role of Omentin-1 in Cancers Development and Progression.

Adipose tissue serves as an energy store and is also an active endocrine organ, exerting activity that influences obesity-related processes through the production of regulatory proteins called adipokines or adipocytokines. Adipokines play important direct and indirect roles in the pathogenesis of insulin resistance, the regulation of local and systemic inflammatory processes, and related metabolic complications. There have been an increasing number of studies showing the relationship between some adipokines and carcinogenesis. This work reviews the current literature concerning the effects of omentin-1 on carcinogenesis.

Omentin-1 and diabetes: more evidence but far from enough.

AIMS AND BACKGROUND: Omentin-1 (oment-1) is a type of adipokines that is mainly expressed in visceral fat tissue. Based on accumulating evidence, oment-1 is closely related to diabetes and its complications. However, so far data about oment-1 and diabetes is fragmented. In this review, we focus on the role of oment-1 on diabetes, including its possible signalling pathways, the correlation of circulating omens-1 levels with diabetes and its complications. METHODS: The web of PubMed was searched for articles of relevant studies published until February, 2023. RESULTS AND CONCLUSIONS: Oment-1 might exert its effects by inhibiting the NF-κB pathway and activating the Akt and AMPK-dependent pathways. The level of circulating oment-1 is negatively correlated with the occurrence of type 2 diabetes and some complications, including diabetic vascular disease, cardiomyopathy, and retinopathy, which can be affected by anti-diabetic therapies. Oment-1 could be a promising marker for screening and targeted therapy for diabetes and its complications; however, more studies are still needed.

Omentin-1 ameliorates experimental inflammatory bowel disease via Nrf2 activation and redox regulation.

AIMS: Omentin-1 production is decreased in patients with IBD. However, the specific role of Omentin-1 in IBD has not been fully elucidated. This study aimed to investigate the expression and role of Omentin-1 in IBD and the potential mechanisms. MAIN METHODS: We collected human serum and colon biopsy samples at the Wuhan Union Hospital. Omentin-1 recombinant protein was injected intraperitoneally in a DSS-induced experimental IBD mouse model. Omentin-1 levels were measured in IBD patients, colitis mice, and LPS-induced HT-29 cells. Omentin-1 and/or a Nrf2 specific inhibitor (ML385) were administered to DSS mice and LPS-induced HT-29 cells. The effects of Omentin-1 on inflammation, intestinal barrier function, Nrf2 pathway, oxidative stress, and NF-κB signaling were detected in vivo and in vitro. KEY FINDINGS: Serum Omentin-1 levels were significantly reduced in UC and CD patients compared with controls (173.7 (IQR, 120.1-221.2) ng/ml, 80.8 (43.8-151.8) ng/ml, and 270.7 (220.7-306.5) ng/ml, respectively). The levels of Omentin-1 were also significantly lower in colitis mice and LPS-induced HT-29 cells. Omentin-1 treatment effectively ameliorated inflammation and impaired intestinal barrier, decreased ROS and MDA levels, and increased GSH and SOD production in the DSS-induced colitis mice and LPS-induced HT-29 cells. Mechanically, Omentin-1 repaired the intestinal barrier by activating Nrf2, then improving oxidative stress and inhibiting NF-κB signaling. Furthermore, the interaction between Omentin-1 and Nrf2 was identified. SIGNIFICANCE: Omentin-1 activates the Nrf2 pathway to regulate redox balance, ultimately protecting intestinal barrier function and reducing intestinal inflammation. In general, Omentin-1 can be used as a promising therapeutic target for IBD.

Role of omentin-1 in susceptibility to anxiety and depression like behaviors.

Neuro-inflammation and blood-brain barrier (BBB) dysfunction are associated with depression. Evidence shows that adipokines enter the brain from the circulation, which regulates depressive behaviors. Omentin-1 is a newly identified adipocytokine that has anti-inflammatory effects, but little is known about its role in neuro-inflammation and mood-relevant behavior. Our results showed omentin-1 knockout mice (Omentin-1-/-) increased susceptibility to anxiety and depressive-like behaviors, which are associated with abnormalities of cerebral blood flow (CBF) and impaired BBB permeability. Moreover, omentin-1 depletion significantly increased hippocampal pro-inflammatory cytokines (IL-1ß, TNFα, IL-6), caused microglial activation, inhibited hippocampus neurogenesis, and resulted in autophagy impairment by dysregulating ATG genes. Omentin-1 deficiency also sensitized mice to the behavioral changes induced by lipopolysaccharide (LPS), suggesting that omentin-1 could rescue neuro-inflammation by acting as an anti-depressant. Our in vitro microglia cell culture data confirmed that recombinant omentin-1 suppresses microglial activation and pro-inflammatory cytokine expression induced by LPS. Our study suggests that omentin-1 can be used as a promising therapeutic agent for the prevention or treatment of depression by providing a barrier-promoting effect and an endogenous anti-inflammatory balance to downregulate the proinflammatory cytokines.

In the Pursuit of Metabolic Markers of Systemic Sclerosis-Plasma Adiponectin and Omentin-1 in Monitoring the Course of the Disease.

Systemic sclerosis (SSc) is a connective tissue disease leading to cutaneous and visceral fibrosis. Pathological features of SSc include immune dysregulation, vasculopathy, and impaired angiogenesis. Adipokines act as cytokines and hormones and are involved in various pathological processes, including metabolic disorders, inflammation, vasculopathy, and fibrosis. This study aimed to determine the level of omentin-1 and adiponectin to evaluate their potential role in the pathogenesis of SSc. We assessed serum omentin-1 and adiponectin as well as metabolic parameters in 58 patients with SSc and 30 healthy controls. The follow-up was performed in SSc individuals. Omentin-1 levels were significantly higher in SSc individuals as compared to the controls. In post-hoc analysis, omentin-1 was higher in the group with disease duration ≥7 years than in the control group. A positive correlation was noted between disease duration and both adipokines and increased with longer disease duration. However, there were no correlations between selected adipokines and metabolic parameters. Enhanced omentin-1 levels and higher levels of omentin-1 in patients with longer disease duration may suggest that omentin-1 is involved in the pathomechanisms of SSc as its concentrations are not directly related to BMI, age, and insulin resistance.