Nesfatin-1 ameliorates oxidative bowel injury in rats with necrotizing enterocolitis: The role of the microbiota composition and claudin-3 expression

Nesfatin-1 regulates the HMGB1-TLR4-NF-κB signaling pathway to inhibit inflammation and its effects on the random skin flap survival in rats

OBJECTIVE

Random skin flaps are often placed by plastic surgeons to treat limb deformities and dysfunction. Nesfatin-1 (NES) is a peptide that exerts angiogenic, anti-inflammatory, and anti-oxidant effects. We assessed the impact of NES on flap survival and the underlying mechanism.

METHODS

We modified the McFarlane random skin flap rat model. Thirty-six male Sprague-Dawley rats were randomly divided into a control group (corn oil solution with DMSO), low-dose group (NES-L at 10 µg/kg/day), and high-dose group (NES-H at 20 µg/kg/day). On day 7 after surgery, average flap survival areas were calculated. Laser Doppler blood flow monitoring and lead oxide/gelatin angiography were used to evaluate blood perfusion and neovascularization, respectively. Flap histopathological status was evaluated by hematoxylin and eosin (H&E) staining. The levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were determined. Immunohistochemical techniques were used to evaluate the expression of angiogenetic and inflammatory factors.

RESULTS

In the experimental groups, the mean skin flap survival areas and blood perfusion increased considerably. The SOD activities in the experimental groups increased and the MDA contents decreased. Immunohistochemically, VEGF expression was upregulated in the experimental groups and the expression levels of inflammatory factors decreased markedly.

CONCLUSION

NES inhibited ischemic skin flap necrosis, promoted angiogenesis, and reduced ischemia-reperfusion injury and inflammation. Inhibition of the inflammatory HMGB1-TLR4-NF-κB signal pathway, which reduced flap inflammation and oxidative stress, may explain the enhanced flap survival.

Nesfatin-1 peptide protects rat renal epithelial cells against high glucose and H2O2 induced injury via inhibition of oxidative stress, apoptosis, and fibrosis

Nesfatin-1 is a potent polypeptide and plays a crucial role in many physiological functions. Nesfatin-1 levels are reported in both the central nervous system and peripheral organs. However, the expression of nesfatin-1 in the renal system under chronic oxidative stress-induced conditions and the direct effect of nesfatin-1 treatment on stress-induced pathological damage are not reported. Thus, the present study aimed to explore the role of nesfatin-1 in vitro in oxidative stress-induced renal epithelial cells. High glucose (HG) and H2O2 combination were used to induce oxidative stress (OS). MTT, crystal violet, and H and E staining were used to measure cell viability, cytotoxicity, and morphology. FACS analysis and confocal microscopy were used to measure OS and apoptosis. RT-PCR was done for gene expression analysis. Decreased nesfatin-1 expression was observed in renal epithelial cells induced with HG and H2O2 compared to an untreated control (0.16; p < 0.0001). Nesfatin-1 co-treatment with HG and H2O2 attenuated ROS, apoptosis, and fibrosis. SOD, Catalase, and Bcl-2 expression decreased (p < 0.0001) and Caspase-3 and TGF-β1 expression increased in HG and H2O2-induced cells compared to control cells (p < 0.0001). Nesfatin-1 co-treatment attenuated these changes induced by HG and H2O2 (p < 0.0001). Nesfatin-1 expression was decreased in renal epithelial cells under stress-induced conditions. Moreover, nesfatin-1 co-treatment under stress-induced conditions protects the renal epithelial cells via inhibition of oxidative stress, apoptotic, and fibrotic signaling pathways.

Role of brain NUCB2/nesfatin-1 in stress and stress-related gastrointestinal disorders

Since the discovery of NUCB2/nesfatin-1 as a novel anorexigenic factor, the expanding function of this peptide has been elucidated in recent years. Increasing evidence suggests that NUCB2/nesfatin-1 is also involved in the regulation of stress and stress-related gastrointestinal disorders. Therefore, we investigated the relationship between NUCB2/nesfatin-1, stress and stress-related gastrointestinal disorders and summarized the results of these studies. Different stressors and duration of stress activate different NUCB2/nesfatin-1-associated brain regions and have different effects on serum corticosterone levels. Central and peripheral NUCB2/nesfatin-1 mediates stress-related gastrointestinal disorders but appears to be protective against inflammatory bowel disease. NUCB2/nesfatin-1 plays an important role in mediating the brain-gut crosstalk, but precise clarification is still needed to gain more insight into these complex relationships.

Nesfatin-1 exerts protective effects on acidosis-stimulated chondrocytes and rats with adjuvant-induced arthritis by inhibiting ASIC1a expression

Nesfatin-1, a newly identified energy-regulating peptide, has been reported to possess antioxidant, anti-inflammatory, and antiapoptotic properties; however, to date, its effect on rheumatoid arthritis (RA) has not been previously explored in detail. We previously showed that activation of acid-sensing ion channel 1a (ASIC1a) by acidosis plays an important role in RA pathogenesis. Therefore, in this study, we evaluated the effects of nesfatin-1 on acidosis-stimulated chondrocyte injury in vitro and in vivo and examined the involvement of ASIC1a and the mechanism underlying the effects of nesfatin-1 on RA. Acid-stimulated articular chondrocytes were used to examine one of the several possible mechanisms underlying RA pathogenesis in vitro. The mRNA expression profile of acid-induced chondrocytes treated or not treated with nesfatin-1 was investigated by RNA sequencing. The effects of nesfatin-1 on oxidative stress, inflammation, and apoptosis in acid-induced chondrocytes were measured. The mechanistic effect of nesfatin-1 on ASIC1a expression and intracellular Ca²⁺ in acid-stimulated chondrocytes was studied. Rats with adjuvant-induced arthritis (AA) were used for in vivo analysis of RA pathophysiology. Cartilage degradation and ASIC1a expression in chondrocytes were detected in rats with AA after intraarticular nesfatin-1 injection. The in vitro experiments showed that nesfatin-1 decreased acidosis-induced cytotoxicity and elevation of intracellular Ca²⁺ levels in chondrocytes. Moreover, it attenuated acid-induced oxidative stress, inflammation, and apoptosis in chondrocytes. Nesfatin-1 decreased ASIC1a protein levels in acid-stimulated chondrocytes via the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) and nuclear factor kappa-B (NF-κB) signaling pathways. In vivo analysis showed that nesfatin-1 ameliorated cartilage degradation and decreased ASIC1a expression in the chondrocytes of rats with AA. Collectively, nesfatin-1 suppressed acidosis-induced oxidative stress, inflammation, and apoptosis in acid-stimulated chondrocytes and alleviated arthritis symptoms in rats with AA, and its mechanism may be related to its ability to decrease ASIC1a protein levels via the MAPK/ERK and NF-κB pathways.

"Sibling" battle or harmony: crosstalk between nesfatin-1 and ghrelin

Ghrelin was first identified as an endogenous ligand of the growth hormone secretagogue receptor (GHSR) in 1999, with the function of stimulating the release of growth hormone (GH), while nesfatin-1 was identified in 2006. Both peptides are secreted by the same kind of endocrine cells, X/A-like cells in the stomach. Compared with ghrelin, nesfatin-1 exerts opposite effects on energy metabolism, glucose metabolism, gastrointestinal functions and regulation of blood pressure, but exerts similar effects on anti-inflammation and neuroprotection. Up to now, nesfatin-1 remains as an orphan ligand because its receptor has not been identified. Several studies have shown the effects of nesfatin-1 are dependent on the receptor of ghrelin. We herein compare the effects of nesfatin-1 and ghrelin in several aspects and explore the possibility of their interactions.

Minireview: Peripheral Nesfatin-1 in Regulation of the Gut Activity—15 Years since the Discovery

Simple Summary

Nesfatin-1 is a newly identified molecule derived from the precursor protein NEFA/nucleobindin2. In this minireview we analyzed the research on the nesfatin-1 localization in the gastrointestinal tract of the mammals. We also referred to the effects of the protein on disorders in the gastrointestinal tract.

Abstract

Nesfatin-1, discovered in 2006, is an anorexigenic molecule derived from the precursor protein NEFA/nucleobindin2. It is generally postulated that this molecule acts through a specific G protein-coupled receptor, as yet unidentified. Research conducted over the last 15 years has revealed both central and peripheral actions of nesfatin-1. Given its major central role, studies determining its inhibitory effect on food intake seem to be of major scientific interest. However, in recent years a number of experiments have found that peripheral organs, including those of the gastrointestinal tract (GIT), may also be a source (possibly even the predominant source) of nesfatin-1. This mini-review aimed to summarize the current state of knowledge regarding the expression and immunoreactivity of nesfatin-1 and its possible involvement (both physiological and pathological) in the mammalian GIT. Research thus far has shown very promising abilities of nesfatin-1 to restore the balance between pro-oxidants and antioxidants, to interplay with the gut microbiota, and to alter the structure of the intestinal barrier. This necessitates more extensive research on the peripheral actions of this molecule. More in-depth knowledge of such mechanisms (especially those leading to anti-inflammatory and anti-apoptotic effects) is important for a better understanding of the involvement of nefatin-1 in GIT pathophysiological conditions and/or for future therapeutic approaches.

Low-dose cyclooxygenase-2 (COX-2) inhibitor celecoxib plays a protective role in the rat model of neonatal necrotizing enterocolitis

This study aims to investigate the effects of the cyclooxygenase-2 (COX-2) inhibitor celecoxib on neonatal necrotizing enterocolitis (NEC) in rats. After treatment with a low dose of celecoxib (0.5, 1, or 1.5 mg/kg), pathological changes in the ileum and the levels of oxidative stress and inflammatory factors in NEC rats were compared. Enzyme-linked immunosorbent assay (ELISA) was employed to detect inflammatory factors, terminal deoxyribonucleotidyl transferase (TdT)-mediated biotin-16-dUTP nick-end labeling (TUNEL) staining was employed to assess apoptotic epithelial cells in the ileum, and real-time quantitative polymerase chain reaction (qRT-PCR) and Western blotting were used to quantify gene and protein expression, respectively. The incidences of NEC rats in the 0.5, 1 and 1.5 mg/kg celecoxib groups were lower than in the model group (100%). Celecoxib improved the histopathology of the ileum in NEC rats. Moreover, low doses of celecoxib relieved oxidative stress and inflammation in NEC rats, as evidenced by decreased tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), total oxidation state (TOS), malondialdehyde (MDA) and oxidative stress index (OSI), as well as increased interleukin-10 (IL-10), total antioxidant status (TAS), superoxide dismutase (SOD) and glutathione peroxidase (GPx). With increasing celecoxib doses (0.5, 1, or 1.5 mg/kg), the amount of apoptotic epithelial cells in the ileum of NEC rats gradually declined and Caspase-3 expression was reduced. The low dose of the COX-2 inhibitor celecoxib ameliorated the histopathologic conditions of the ileum, alleviated oxidative stress and inflammation, and reduced apoptotic epithelial cells in NEC rats, thereby making it a potential therapy for NEC.

Antioxidant, Anti-Inflammatory and Anti-Apoptotic Activities of Nesfatin-1: A Review

Nesfatin-1, a newly identified energy-regulating peptide, is widely expressed in the central and peripheral tissues, and has a variety of physiological activities. A large number of recent studies have shown that nesfatin-1 exhibits antioxidant, anti-inflammatory, and anti-apoptotic properties and is involved in the occurrence and progression of various diseases. This review summarizes current data focusing on the therapeutic effects of nesfatin-1 under different pathophysiological conditions and the mechanisms underlying its antioxidant, anti-inflammatory, and anti-apoptotic activities.

Nesfatin-1 Promotes Proliferation, Migration and Invasion of HTR-8/SVneo Trophoblast Cells and Inhibits Oxidative Stress via Activation of PI3K/AKT/mTOR and AKT/GSK3β Pathway

Preeclampsia (PE) is a leading cause of perinatal and maternal mortality. Considering that Nesfatin-1 was reported to be downregulated in serum of PE patients, we aimed to explore the functional role of Nesfatin-1 in trophoblast cells. Cell transfection was conducted to overexpress or inhibit Nesfatin-1, and its expression was measured by quantitative PCR. Cell proliferation, migration, and invasion abilities were determined employing CCK-8, flow cytometry, wound-healing, and transwell assays. Immunofluorescence assay was performed to detect E-cadherin and vimentin. ROS, MDA, and SOD levels were measured using their corresponding commercial kits. Western blot was used to identify the expression of vital kinases in PI3K/AKT/mTOR or GSK3β pathway and invasion-related proteins in trophoblast cells. Nesfatin-1 knockdown significantly suppressed proliferation, migration, and invasion and increased cell arrest in G1 phase, as well as downregulated expressions of MMP2/9 in HTR-8/SVneo cells. Besides, Nesfatin-1 knockdown promoted the expression of E-cadherin and reduced the expression of vimentin. Additionally, the levels of ROS, MDA, and SOD were elevated upon Nesfatin-1 knockdown. On the contrary, Nesfatin-1 overexpression exerted the opposite effects. Nesfatin-1 promoted the activation of PI3K/AKT/mTOR or GSK3β pathway, blocking of which reversed the promotive effects on trophoblast invasion and the inhibitory effects on oxidative stress of Nesfatin-1 in HTR-8/SVneo cells. In short, this study revealed that Nesfatin-1 promoted trophoblast cell proliferation, migration, invasion, and EMT and suppressed oxidative stress by activating PI3K/AKT/mTOR and AKT/GSK3β signaling pathway, laying the foundation for the development of therapeutic strategy for PE by targeting Nesfatin-1.

Reversal of Increase in Intestinal Permeability by Mangifera indica Seed Kernel Extract in High-Fat Diet-Induced Obese Mice

Obesity and hyper-intestinal permeability are interconnected. This study is designed to evaluate the ability of Mangifera indica seed kernel extract (MESK) in restoring the intestinal barrier and preventing obesity and associated metabolic complications in a high-fat diet-induced obese mouse model. Four groups of Swiss albino mice: (1) normal diet (ND), (2) high-fat diet (HFD), (3) HFD + Orlistat (100 µg/kg), and (4) HFD + MESK (75 µg/kg), were used to monitor various biochemical parameters associated with metabolic syndrome (glucose, total cholesterol, triglycerides) and body weight in an eight-week-long study. In vivo intestinal permeability was determined by the FITC-dextran method. Interestingly, MESK significantly reduced HFD-induced body weight gain, hepatic lipid accumulation, hepatic fibrosis, hyperglycemia, and dyslipidemia. Additionally, MESK treatment restored the expression of tight junction protein Zonula Occludens-1 (ZO-1) and Claudin-1 and hence prevented increased intestinal permeability induced by a high-fat diet. Moreover, it also increased the expression of potent satiety molecule Nesfatin-1 in the mouse jejunum. Our results, for the first time, establish MESK as a nutraceutical which prevents disruption of the intestinal barrier and thereby intercepts the adverse consequences of compromised intestinal permeability such as obesity, hyperglycemia, dyslipidemia, and systemic inflammation.