Cortistatin Research Articles

Cortistatin protects against septic cardiomyopathy by inhibiting cardiomyocyte pyroptosis through the SSTR2-AMPK-NLRP3 pathway

BackgroundAlthough the pathophysiological mechanism of septic cardiomyopathy has been continuously discovered, it is still a lack of effective treatment method. Cortistatin (CST), a neuroendocrine polypeptide of the somatostatin family, has emerged as a novel cardiovascular-protective peptide, but the specific mechanism has not been elucidated. PurposeThe aim of our study is to explore the role of CST in cardiomyocytes pyroptosis and myocardial injury in sepsis and whether CST inhibits cardiomyocytes pyroptosis through specific binding with somastatin receptor 2 (SSTR2) and activating AMPK/Drp1 signaling pathway. Methods and ResultsIn this study, plasma CST levels were significantly high and were negatively correlated with N-terminal pro-B type natriuretic peptide (NT-proBNP), a biomarker for cardiac dysfunction, in patients with sepsis. Exogenous administration of CST significantly improved survival rate and cardiac function in mouse models of sepsis by inhibiting the activation of the NLRP3 inflammasome and pyroptosis of cardiomyocytes (decreased cleavage of caspase-1, IL-1β and gasdermin D). Pharmacological inhibition and genetic ablation revealed that CST exerted anti-pyroptosis effects by specifically binding to somatostatin receptor subtype 2 (SSTR2), thus activating AMPK and inactivating Drp1 to inhibit mitochondrial fission in cardiomyocytes. ConclusionsThis study is the first to report that CST attenuates septic cardiomyopathy by inhibiting cardiomyocyte pyroptosis through the SSTR2-AMPK-Drp1-NLRP3 pathway. Importantly, CST specifically binds to SSTR2, which promotes AMPK phosphorylation, inhibits Drp1-mediated mitochondrial fission, and reduces ROS levels, thereby inhibiting NLRP3 inflammasome activation-mediated pyroptosis and alleviating sepsis-induced myocardial injury.

Cortistatin prevents glucocorticoid-associated osteonecrosis of the femoral head via the GHSR1a/Akt pathway

Long-term use of glucocorticoids (GCs) is known to be a predominant cause of osteonecrosis of the femoral head (ONFH). Moreover, GCs can mediate apoptosis of various cell types by exaggerating oxidative stress. We have previously found that Cortistatin (CST) antagonizes oxidative stress and improves cell apoptosis in several conditions. In this study, we detected that the CST expression levels were diminished in patients with ONFH compared with femoral neck fracture (FNF). In addition, a GC-induced rat ONFH model was established, which impaired bone quality in the femoral head. Then, administration of CST attenuated these ONFH phenotypes. Furthermore, osteoblast and endothelial cells were cultured and stimulated with dexamethasone (Dex) in the presence or absence of recombinant CST. As a result, Dex induced impaired anabolic metabolism of osteoblasts and suppressed tube formation in endothelial cells, while additional treatment with CST reversed this damage to the cells. Moreover, blocking GHSR1a, a well-accepted receptor of CST, or blocking the AKT signaling pathway largely abolished the protective function of CST in Dex-induced disorder of the cells. Taken together, we indicate that CST has the capability to prevent GC-induced apoptosis and metabolic disorder of osteoblasts in the pathogenesis of ONFH via the GHSR1a/AKT signaling pathway.

Transcriptomic analysis identifies the neuropeptide cortistatin (CORT) as an inhibitor of temozolomide (TMZ) resistance by suppressing the NF-κB-MGMT signaling axis in human glioma

Glioma is a common tumor originating in the brain that has a high mortality rate. Temozolomide (TMZ) is the first-line treatment for high-grade gliomas. However, a large proportion of gliomas are resistant to TMZ, posing a great challenge to their treatment. In the study, the specific functions and mechanism(s) by which cortistatin (CORT) regulates TMZ resistance and glioma progression were evaluated. The decreased expression of CORT was detected in glioma tissues, and highly expressed CORT was associated with a better survival rate in patients with glioma. CORT overexpression notably decreased the capacity of glioma cells to proliferate and migrate in vitro and to form tumors in vivo. CORT overexpression also markedly suppressed the viability and enhanced the apoptosis of TMZ-resistant U251 cells by regulating MGMT, p21, and Puma expression. Importantly, CORT overexpression reduced the resistance of gliomas to TMZ in vivo. CORT expression was negatively correlated with MGMT expression in both glioma tissues and cells, and it was found that CORT inhibited NF-κB pathway activation in glioma cells, thereby inhibiting MGMT expression. In conclusion, CORT regulates glioma cell growth, migration, apoptosis, and TMZ resistance by weakening the activity of NF-κB/p65 and thereby regulating MGMT expression. The CORT/NF-κB/MGMT axis might be regarded as a molecular mechanism contributing to the resistance of glioma to TMZ. Our data also suggest that CORT regulates the viability and metastatic potential of glioma cells, independent of its effects on TMZ resistance, providing evidence of novel therapeutic targets for glioma that should be evaluated in further studies.

Research on the effect of Dipsaci Radix before and after salt-processed on kidney yang deficiency syndrome rats and the preliminary mechanism study through the BMP-Smad signaling pathway

Ethnopharmacological relevanceDipsaci Radix (DR) is the dry root of Dipsacus asper Wall. ex DC. Aim of the studyThe purpose of this study was to compare the effects of DR on rats before and after salt-processed with kidney yang deficiency syndrome (KYDS), and we selected the BMP-Smad signaling pathway to explore the mechanism of DR. Materials and methodsThe model of KYDS was established by subcutaneous injection of hydrocortisone, the crude DR (CDR) and salt-processed DR (SDR) were given the corresponding dose (2 g/kg, 4 g/kg, and 6 g/kg). The organ index and the contents of adrenocorticotropic hormone (ACTH), cortistatin (CORT), thyroid hormone (T4), tumor necrosis factor-alpha (TNF-α), testosterone (T), estradiol (E2), cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP), Na+-K+-ATPase, and growth hormone (GH) in serum were measured to evaluate the intervention effect of DR on KYDS rats. The expression of Smad 1, Smad 4, Smad 5, Smad 8, and BMP 7 protein in kidney was determined by immunohistochemistry, quantitative PCR (qPCR) and Western blot analysis. The effects of DR on 5 expression factors in the BMP-Smad signaling pathway were studied. Constituents absorbed into blood were identified by UPLC-Q-TOF/MS. ResultsThe results showed that compared with the model group, the thymus and kidney index, as well as the contents of ACTH, CORT, cAMP, GH, Na+-K+-ATPase, T, T4, and E2 were significantly increased in the CDR and SDR groups, and the contents of cGMP and TNF-α were significantly decreased. Compared with the CDR high dose group, ACTH, Na+-K+-ATPase, T, and T4 were significantly increased in the SDR high dose group. The results of immunohistochemistry, qPCR, and Western blot analysis showed that compared with the model group, the expression levels of Smad 1, Smad 4, Smad 5, Smad 8 and BMP 7 proteins in the kidney of DR groups were significantly increased. And SDR groups tended to be better than CDR groups. 8 constituents migrating to blood were identified. ConclusionThis study showed that both CDR and SDR could have a good therapeutic effect on KYDS, and SDR was better than CDR. This study chose the BMP-Smad signaling pathway to study the mechanism of DR in the treatment of KYDS and provided a scientific basis for the processing mechanism of salt-processed.

Serum Cortistatin Level in Type 2 Diabetes Mellitus and Its Relationship with Nonalcoholic Fatty Liver Disease.

To evaluate serum cortistatin (CST) levels in type 2 diabetes mellitus (T2DM) patients with or without non-alcoholic fatty liver disease (NAFLD) and to examine the relationship between CST and NAFLD. A total of 90 T2DM patients, which included 56 NAFLD patients (referred to as DM+NAFLD group) and 34 patients without NAFLD (DM-only group), and 83 non-diabetes individuals that included 39 NAFLD patients (NAFLD-only group) and 44 without NAFLD that acted as the normal-control group (NC group). The differences in the serum CST levels between the groups were compared, and the correlations between CST and other variables were calculated by applying both correlational analysis and multiple linear regression analysis. The mean serum CST levels were significantly lower in the DM+NAFLD and DM groups than in the NC group (P < 0.05). In addition, the CST levels were lower in the DM group relative to that in the NAFLD group (P < 0.05). However, no statistical difference was noted in the serum CST between diabetic patients with and without NAFLD (P > 0.05). Similarly, in the non-diabetic group, the serum CST level was not significantly different between individuals with and without NAFLD (P > 0.05). Furthermore, the serum CST levels were negatively associated with the levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG), homeostasis model assessment-insulin resistance (HOMA-IR), and insulin cell function index (HOMA-β). Conversely, the serum CST levels were positively associated with high-density lipoprotein cholesterol (HDL-C). The data obtained through multiple linear regression implied that LDL-C and HOMA-β, but not HOMA-IR, were closely related to serum CST levels. T2DM was related to decreased serum CST. However, serum CST was correlated with HOMA-β in T2DM patients, while HOMA-IR was not. There was no correlation between CST and NAFLD.

Somatostatin, Cortistatin and Their Receptors Exert Antitumor Actions in Androgen-Independent Prostate Cancer Cells: Critical Role of Endogenous Cortistatin.

Somatostatin (SST), cortistatin (CORT), and their receptors (SSTR1-5/sst5TMD4-TMD5) comprise a multifactorial hormonal system involved in the regulation of numerous pathophysiological processes. Certain components of this system are dysregulated and play critical roles in the development/progression of different endocrine-related cancers. However, the presence and therapeutic role of this regulatory system in prostate cancer (PCa) remain poorly explored. Accordingly, we performed functional (proliferation/migration/colonies-formation) and mechanistic (Western-blot/qPCR/microfluidic-based qPCR-array) assays in response to SST and CORT treatments and CORT-silencing (using specific siRNA) in different PCa cell models [androgen-dependent (AD): LNCaP; androgen-independent (AI)/castration-resistant PCa (CRPC): 22Rv1 and PC-3], and/or in the normal-like prostate cell-line RWPE-1. Moreover, the expression of SST/CORT system components was analyzed in PCa samples from two different patient cohorts [internal (n = 69); external (Grasso, n = 88)]. SST and CORT treatment inhibited key functional/aggressiveness parameters only in AI-PCa cells. Mechanistically, antitumor capacity of SST/CORT was associated with the modulation of oncogenic signaling pathways (AKT/JNK), and with the significant down-regulation of critical genes involved in proliferation/migration and PCa-aggressiveness (e.g., MKI67/MMP9/EGF). Interestingly, CORT was highly expressed, while SST was not detected, in all prostate cell-lines analyzed. Consistently, endogenous CORT was overexpressed in PCa samples (compared with benign-prostatic-hyperplasia) and correlated with key clinical (i.e., metastasis) and molecular (i.e., SSTR2/SSTR5 expression) parameters. Remarkably, CORT-silencing drastically enhanced proliferation rate and blunted the antitumor activity of SST-analogues (octreotide/pasireotide) in AI-PCa cells. Altogether, we provide evidence that SST/CORT system and SST-analogues could represent a potential therapeutic option for PCa, especially for CRPC, and that endogenous CORT could act as an autocrine/paracrine regulator of PCa progression.

The Number of MRGPRX2-Expressing Cells Is Increased in Skin Lesions of Patients With Indolent Systemic Mastocytosis, But Is Not Linked to Symptom Severity.

BackgroundRecently, the expression of the mast cell (MC) receptor Mas-related G protein–coupled receptor X2 (MRGPRX2) has been detected in lesional skin of adult patients with cutaneous mastocytosis. As of yet, little is known about the clinical relevance of MRGPRX2 and its agonists in patients with mastocytosis, including indolent systemic mastocytosis (ISM).MethodsMRGPRX2 and MRGPRX2 agonists, cortistatin (CST), and major basic protein (MBP) were analyzed in lesional and non-lesional skin of patients with ISM and skin of healthy controls by immunohistochemistry. Co-localization of MRGPRX2 and MRGPRX2-mRNA with the MC marker tryptase was assessed by immunofluorescence microscopy and in situ hybridization, respectively. We assessed clinical, demographic, and laboratory data, including mastocytosis activity score (MAS), serum tryptase, and KIT D816V allele burden.ResultsThe number of MRGPRX2-expressing (MRGPRX2+) cells, MRGPRX2-mRNA+ MCs, and CST-expressing (CST+) and MBP-expressing (MBP+) cells was significantly higher in lesional skin as compared to non-lesional skin and/or skin of healthy controls (all p < 0.05). Increased numbers of MRGPRX2+ cells, MRGPRX2-mRNA+ MCs, and CST+ and MBP+ cells were not associated with clinical and laboratory features of ISM, including disease burden, symptom severity, evidence of anaphylaxis, and tryptase levels.ConclusionsSkin lesions of patients with ISM showed high numbers of MRGPRX2+ cells, although they were not linked to symptom severity. Clinical relevance of the MRGPRX2-mediated pathway of MC activation in ISM remains unclear and should be investigated in further studies.

Evaluation of a Novel DNA Vaccine Double Encoding Somatostatin and Cortistatin for Promoting the Growth of Mice.

Simple SummaryGrowth trait is one of the most important economic traits for meat animals. Somatostatin DNA vaccine has been proven to enhance the growth rate of animals. However, the growth-promoting effect is not ideal. This study aimed to evaluate the immune effects of a novel eukaryotic dual expression vaccine known as pIRES-S/CST14-S/2SS in mice. Firstly, we demonstrated pIRES-S/CST14-S/2SS could functionally express in GH3 pituitary cells by regulating the growth hormone (GH) and prolactin (PRL) productions. Secondly, we observed that all concentrations of pIRES-S/CST14-S/2SS vaccine could evoke anti-somatostatin (SS) antibodies, leading to a higher level of GH concentration. Notably, pIRES-S/CST14-S/2SS (10 μg/100 μL) immunized mice obtained maximum body weight gain in a booster vaccination period. Our results are helpful for better understanding of the relationship between SS and CST, and pIRES-S/CST14-S/2SS vaccine may be used as a promising alternative for developing growth-promoting vaccine.Animal growth traits are directly linked with the economics of livestock species. A somatostatin DNA vaccine has been developed to improve the growth of animals. However, the growth-promoting effect is still unsatisfying. The current study aimed to evaluate the effect of a novel eukaryotic dual expression vaccine known as pIRES-S/CST14-S/2SS, which encodes the genes obtained by fusing somatostatin (SS) and cortistatin (CST) into hepatitis B surface antigen (HBsAg). After transfection into GH3 cells with pIRES-S/CST14-S/2SS, green fluorescence signals were observed by fluorescence microscopy, suggesting the effective expression of CST and SS in GH3 cells using the IRES elements. Subsequently, both GH and PRL levels were found to be significantly lower in pIRES-S/CST14-S/2SS-treated cells as compared to the control group (p < 0.05). Furthermore, the antibody level, hormone secretion, and weight gain in the mice injected with novel recombinant plasmids were also evaluated. The anti-SS antibodies were detectable in all vaccine treated groups, resulting in significantly higher levels of GH secretion (p < 0.05). It is worth mentioning that pIRES-S/CST14-S/2SS (10 μg/100 μL) vaccinated mice exhibited a higher body weight gain in the second immunization period. This study increases the understanding of the relationship between somatostatin and cortistatin, and may help to develop an effective growth-promoting DNA vaccine in animals.

The neuropeptide cortistatin attenuates Th17 cell response through inhibition of glycolysis via GHSR1

The neuropeptide cortistatin (CST) has been reported to attenuate Th17 cell response in multiple disease models, but the mechanism of action remains obscure. Here, we show that either overexpression or exogenous addition of CST obviously restricts Th17 cell differentiation. As metabolic reprogramming plays an important role in Th17 cell development, we explore whether CST inhibits Th17 cell differentiation by regulating glycolysis. The results show that CST substantially attenuates the glycolysis during Th17 differentiation and down-regulates the mRNA expression of myelocytomatosis oncogene (Myc) and hexokinase 2 (HK2), the glycolysis rate-limiting enzyme. Following the overexpression of Myc and HK2, the inhibitory effect of CST on Th17 differentiation nearly disappears, suggesting that Myc-HK2 pathway is deeply involved. Furthermore, growth hormone secretagogue receptor 1 (GHSR1) is identified as the key receptor subtype for CST attenuating glycolysis and Th17 cell differentiation by the combined uses of CST with various receptor subtype blockers. The knockdown of GHSR1 abrogates the inhibition of CST on Th17 differentiation and glycolysis. Finally, in the colitis mice induced by dextran sulfate sodium, an intraperitoneal injection of CST markedly inhibits Th17 cell response and down-regulates the expression of HK2 in the Th17 cells, which is reversed by the combined use of GHSR1 antagonist. These findings suggest that inhibition of glycolysis is the key pathway for CST attenuating Th17 cell response, and GHSR1, Myc and HK2 are potential therapeutic targets of Th17 cell-related diseases.

Cortistatin Inhibits Intestinal Ion Secretion via Activating the Somatostatin‐2 Receptor in the Submucosal Neurons of the Mouse Colon

Background and AimsCortistatin (CST) is a somatostatin‐like neuropeptide that is found in both the central and peripheral nervous system. CST binds with high affinity to all somatostatin receptors and also has actions not shared by somatostatin. We previously found that CST is expressed by enteric neurons in the guinea pig ileum and acts as an inhibitory neurotransmitter in the submucosal plexus. The aim of the present study was to evaluate the effect of CST on neurogenic intestinal secretion.MethodsMucosal/submucosal flat‐sheet preparations from mouse proximal colon were mounted in Ussing flux chambers for measurement of short‐circuit current (Isc) as an indicator of mucosal secretion. Transmural electrical field stimulation (EFS) evoked characteristic biphasic increases in Isc, with an early rapidly rising phase followed by a sustained phase.ResultsApplication of CST‐14, CST‐17, or CST‐29 to the basolateral side of the mucosal/submucosal preparation decreased baseline Isc in a concentration‐dependent manner with an IC50 of 90.5 nM, 52.1 nM, or 102.9 nM, respectively. The somatostatin‐2 receptor (SSTR‐2) antagonist CYN 154806 (1 mM) significantly suppressed CST‐14 (100 nM), CST‐17 (100 nM), or CST‐29 (100 nM)‐evoked ΔIsc by 36.0 ± 8.2% (n=5; P &lt; 0.05), 47.2 ± 11.2% (n=5; P &lt; 0.01), or 51.7.0 ± 8.4% (n=5; P &lt; 0.01), respectively. The neuronal blocker tetrodotoxin (300 nM) significantly reduced CST‐14 (100 nM), CST‐17 (100 nM), or CST‐29 (100 nM)‐evoked ΔIsc by 36.5 ± 2.7% (n=5; P &lt; 0.01), 48.9 ± 11.2% (n=5; P &lt; 0.01), or 49.5 ± 3.6% (n=5; P &lt; 0.01), respectively. All of the CSTs (1 nM – 1 mM) also produced a concentration‐dependent reduction of the EFS‐evoked biphasic secretory responses. The effect of CSTs on the EFS‐evoked responses was antagonized by CYN 154806 (1 mM). Immunohistochemical staining with a CST‐17 polyclonal antibody revealed expression of CST‐17 immunoreactivity (IR) in mouse colonic submucosal neurons. CST‐17‐IR was localized in cholinergic secretomotor neurons but was absent from non‐cholinergic secretomotor neurons and calbindin‐IR neurons.ConclusionsThe results suggest that CST acts at SST‐2 receptors in the submucosal plexus to suppress secretomotor neuronal excitability and neurogenic intestinal secretion in the mouse colon.

Cortistatin attenuates titanium particle-induced osteolysis through regulation of TNFR1-ROS-caspase-3 signaling in osteoblasts.

Aseptic loosening is a major complication of prosthetic joint surgery and is associated with impaired osteoblast homeostasis. Cortistatin (CST) is a neuropeptide that protects against inflammatory conditions. In this study, we found that expression of CST was diminished in patients with prosthetic joint loosening and in titanium (Ti) particle-induced animal models. A Ti particle-induced calvarial osteolysis model was established in wild-type and CST gene knockout mice; CST deficiency enhanced, while exogenously added CST attenuated, the severity of Ti particle-mediated osteolysis. CST protected against inflammation as well as apoptosis and maintained the osteogenic function of MC3T3-E1 osteoblasts upon stimulation with Ti particles. Furthermore, CST antagonized reactive oxygen species production and suppressed caspase-3-associated apoptosis mediated by Ti particles in osteoblasts. Additionally, CST protects against Ti particle-induced osteolysis through tumor necrosis factor receptor 1. Taken together, CST might provide a therapeutic strategy for wear debris-induced inflammatory osteolysis.

Mast cells, cortistatin, and its receptor, MRGPRX2, are linked to the pathogenesis of chronic prurigo

Chronic prurigo (CPG) is characterized by intensive itch and interactions among nerves, neuropeptides, and mast cells (MCs). The role of some neuropeptides such as cortistatin (CST) and its receptor, Mas-related G protein-coupled receptor X2 (MRGPRX2), in CPG remains poorly investigated. We evaluated first whether CST activates human skin MCs, and second whether CST and MRGPRX2 are expressed in the skin of CPG patients, and by which cells. Skin prick tests and microdialysis with CST were performed in 6 and 1 healthy volunteers, respectively. Degranulation of human skin MCs was assessed using β-hexosaminidase and histamine release assays. Skin samples from 10 patients with CPG and 10 control subjects were stained for CST, MCs, and MRGPRX2 (protein and mRNA) using immunohistochemistry, immunofluorescence, and/or in situ hybridization. Flow cytometry was used to assess CST in human skin MCs. MRGPRX2 levels were measured in serum by ELISA. CST induced concentration-dependent degranulation of human skin MCs invivo and exvivo. Skin lesions of CPG patients exhibited markedly higher numbers of CST-expressing cells, CST-expressing MCs, MRGPRX2-expressing cells, and MRGPRX2 mRNA-expressing cells than nonlesional skin. MCs were the main MRGPRX2 mRNA-expressing cells in the lesions of most CPG patients (70%). Stimulation of human skin MCs with anti-IgE led to a release of CST. The number of MRGPRX2-expressing cells correlated with disease severity (r= 0.649, P= .04). MRGPRX2 serum levels in CPG patients correlated with disease severity (r= 0.704, P= .023) and quality-of-life impairment (r= 0.687, P= .028). CST and MRGPRX2 may contribute to the pathogenesis of CPG and should be evaluated in further studies as potential biomarkers and novel therapeutic targets.

Convergent Cortistatin losses parallel modifications in circadian rhythmicity and energy homeostasis in Cetacea and other mammalian lineages

The ancestors of Cetacea underwent profound morpho-physiological alterations. By displaying an exclusive aquatic existence, cetaceans evolved unique patterns of locomotor activity, vigilant behaviour, thermoregulation and circadian rhythmicity. Deciphering the molecular landscape governing many of these adaptations is key to understand the evolution of phenotypes. Here, we investigate Cortistatin (CORT), a neuropeptide displaying an important role in mammalian biorhythm regulation. This neuropeptide is a known neuroendocrine factor, stimulating slow-wave sleep, but also involved in the regulation of energy metabolism and hypomotility inducement. We assessed the functional status of CORT in 359 mammalian genomes (25 orders), including 30 species of Cetacea. Our findings indicate that cetaceans and other mammals with atypical biorhythms, thermal constraints and/or energy metabolism, have accumulated deleterious mutations in CORT. In light of the pleiotropic action of this neuropeptide, we suggest that this inactivation contributed to a plethora of phenotypic adjustments to accommodate adaptive solutions to specific ecological niches.

Cortistatin protects against inflammatory airway diseases through curbing CCL2 and antagonizing NF-κB signaling pathway

Asthma is a chronic inflammatory disease affecting millions of people around the world, yet much remains unknown about its underlying mechanisms. Cortistatin (CST) is a neuropeptide which is reported to be a potential endogenous anti-inflammatory factor in several conditions. To testify the potential involvement of CST in airway inflammatory reaction, an ovalbumin (OVA)-induced mice model was established in wild-type (WT) as well as CST-knockout (Cort-/-) mice. Thereafter, lung tissue or cell samples were gathered in each group, and histological analysis as well as cell counting assay indicated that Cort-/- mice exhibited exaggeration of asthma compared with WT control group. Moreover, mRNA sequencing assay revealed that CCL2 was a potential target of CST in asthma, and administration of CCL2 inhibitor alleviated airway inflammation of asthma in Cort-/- mice. Moreover, NF-κB signaling pathway might be closely associated with the protective function of CST in asthma, as enhanced activation of NF-κB signaling pathway was observed in OVA-induced asthma model of Cort-/- mice, and SN50, an inhibitor of NF-κB signaling pathway, antagonized asthma development in Cort-/- mice. In summary, CST might represent as a promising target for the treatment of asthma through interacting with CCL2 and NF-κB signaling pathway.

Cortistatin ameliorates Ang II-induced proliferation of vascular smooth muscle cells by inhibiting autophagy through SSTR3 and SSTR5

AimsVascular smooth muscle cell (VSMC) proliferation plays a significant role in the development of various vascular disorders. However, the effect of cortistatin (CST) on VSMC proliferation remains unclear. Therefore, the purpose of our research aimed to study whether CST protected VSMCs from angiotensin II (Ang II)-induced proliferation and which mechanisms participated in the process. Main methodsCultured rat VSMCs were treated with Ang II with or without CST for 24 h. Cell proliferation rate was measured by cell counting kit-8 (CCK8) assay. The expressions of CST and its receptors were assessed by quantitative real-time PCR (qRT-PCR). The protein expression levels were analyzed by western blots. Immunofluorescence and transmission electron microscopy (TEM) were used to observe autophagy. Key findingsOur results showed that different concentrations of CST alleviated the Ang II-induced VSMC proliferation. The autophagy and reactive oxygen species (ROS) stimulated by Ang II were attenuated by CST. Furthermore, when the autophagy inhibitor 3-methyladenine (3-MA) was added, it exerted similar inhibition effects like CST, but didn't augment the protective role of CST on Ang II-induced VSMC autophagy and proliferation. Moreover, blocking somatostatin receptor 3 and 5 (SSTR3 and SSTR5) partially abrogated the suppressive effect of CST on Ang II-stimulated VSMC proliferation and autophagy. SignificanceThis study indicated that CST could ameliorate Ang II-stimulated VSMC proliferation by inhibiting autophagy partially through its receptors SSTR3 and SSTR5, providing a reasonable evidence for CST as a novel perspective therapeutic target of vascular diseases.

Cardioprotection of cortistatin against isoproterenol-induced myocardial injury in rats.

BackgroundThe present study was designed to examine whether cortistatin (CORT) could protect rats from myocardial injury induced by subcutaneously injecting isoproterenol (ISO) and to clarify the possible mechanisms.MethodsMale Sprague-Dawley (SD) rats were placed at random into four groups: the control group, the ISO group, the ISO + CORT 25 µg/(kg·d) group, and the ISO + CORT 50 µg/(kg·d) group. Rat models of myocardial injury were established with the subcutaneous (s.c.) injections of 85 mg/kg ISO for 2 days. In the ISO+ CORT 25 µg/(kg·d) group and ISO+ CORT 50 µg/(kg·d) group, rats were given s.c. injections of CORT 25 µg/(kg·d) and CORT 50 µg/(kg·d) on the day before ISO, 3 days, respectively. Serum malondialdehyde (MDA) content, lactate dehydrogenase (LDH) activity, and creatine kinase isoenzyme (CK-MB) activity were measured by corresponding test kits. Western blot was applied to evaluate the expression of endoplasmic reticulum stress-related protein glucose regulatory protein 78 (GRP78), enhancer-binding protein homologous protein (CHOP), cysteinyl aspartate specific proteinase-12 (caspase-12), LC3-II, Beclin-1, and p62 in the rat myocardium.ResultsCORT alleviated the increased enzyme activities of serum LDH and CK-MB, and content of MDA (a typical marker of lipid peroxidation) in rats induced by ISO. CORT also prevented pathological myocardial injury in rats induced by ISO. Moreover, CORT attenuated the increased protein levels of GRP78, CHOP, and caspase-12, and reduced the increase of LC3-II, LC3-II/I, Beclin-1, and p62 in rats induced by ISO.ConclusionsThese data demonstrate that CORT can attenuate ISO-induced acute myocardial injury in rats likely by reducing lipid peroxidation, and inhibiting endoplasmic reticulum stress and autophagy. This supports CORT as a potentially being a new target for preventing and treating myocardial injury and its related disease.

Cortistatin protects against intervertebral disc degeneration through targeting mitochondrial ROS-dependent NLRP3 inflammasome activation.

Background: Intervertebral disc (IVD) degeneration is a common degenerative disease that can lead to collapse or herniation of the nucleus pulposus (NP) and result in radiculopathy in patients.Methods: NP tissue and cells were isolated from patients and mice, and the expression profile of cortistatin (CST) was analysed. In addition, ageing of the NP was compared between 6-month-old WT and CST-knockout (CST-/-) mice. Furthermore, NP tissues and cells were cultured to validate the role of CST in TNF-α-induced IVD degeneration. Moreover, in vitro and in vivo experiments were performed to identify the potential role of CST in mitochondrial dysfunction, mitochondrial ROS generation and activation of the NLRP3 inflammasome during IVD degeneration. In addition, NF-κB signalling pathway activity was tested in NP tissues and cells from CST-/- mice.Results: The expression of CST in NP cells was diminished in the ageing- and TNF-α-induced IVD degeneration process. In addition, compared with WT mice, aged CST-/- mice displayed accelerated metabolic imbalance and enhanced apoptosis, and these mice showed a disorganized NP tissue structure. Moreover, TNF-α-mediated catabolism and apoptosis were alleviated by exogenous CST treatment. Furthermore, CST inhibited mitochondrial dysfunction in NP cells through IVD degeneration and suppressed activation of the NLRP3 inflammasome. In vitro and ex vivo experiments indicated that increased NF-κB pathway activity might have been associated with the IVD degeneration observed in CST-/- mice.Conclusion: This study suggests the role of CST in mitochondrial ROS and activation of the NLRP3 inflammasome in IVD degeneration, which might shed light on therapeutic targets for IVD degeneration.

Anti-inflammatory effect of cortistatin in rat endotoxin-induced uveitis model.

Purpose:To evaluate the anti-inflammatory effect of cortistatin (CST) in endotoxin-induced uveitis (EIU) model and to compare the results with corticosteroid treatment.Methods:A total of 35 healthy Wistar albino rats were randomly divided into five groups. EIU was induced by a single subcutaneous injection of lipopolysaccharide (LPS). Group I received intraperitoneal (ip) normal saline (NS), Group II received ip 150 μg LPS plus NS, Group III received ip 150 μg LPS plus 250 μg/kg CST, Group IV received ip 150 μg LPS plus 1mg/kg dexamethasone, and Group V received ip 250 μg/kg CST only. The aqueous humor was collected 24 h after injection and the infiltrating cells were determined. Moreover, histopathological and immunohistochemical examinations were also performed.Results:The clinical score and infiltrated cell count were reduced in Groups III and IV compared with Group II (P < 0.001). The pathological findings of Groups III and IV were significantly reduced compared with Group II (P < 0.001). These findings were similar between Groups III and IV (P = 1.000). Tumor necrosis factor-alpha (TNF-α) and interleukin 1 beta (IL-1β) immunoreactivity in the ciliary body of Group III and Group IV were significantly reduced compared with Group II (P < 0.001). TNF-α and IL-1β immunoreactivity in the ciliary body of Group III and Group IV were similar compared with Group I and Group V (range of P values was 0.539–0.958).Conclusion:CST administration as a therapeutic agent might ameliorate the severity of intraocular inflammation in uveitis patients. In conclusion, effect of CST and dexamethasone in EIU model was comparable.

Cortistatin Dampens Psoriasis-Like Skin Inflammation Through Interacting with TNF-Α/TNFR1/Nf-κB Signaling Pathway and Regulating Macrophage Polarization

Psoriasis is a common autoimmune disease in clinic. TNF-α/TNFR pathway plays a critical role in inflammatory response of various autoimmune diseases, including psoriasis. Cortistatin (CST), a cyclic neuropeptide, is involved in activation of several types of immune cells, and fights against inflammation procedure. Recently, we found that CST directly binds to TNFR and antagonizes TNF-α function. In this study, IMQ induced psoriasis-like skin inflammation mice models were established in wild type mice, TNFR1-/- mice, TNFR2-/- mice and CST-/- mice, followed by assays of inflammatory response. Moreover, macrophages were isolated from stimulated dorsal skin of wild type mice and CST-/- mice, and macrophage polarization was analyzed. Deficiency of CST led to exaggerated skin inflammation, while exogenous CST attenuated skin inflammatory reaction, which was exhibited by destruction of structure and expression of inflammatory biomarkers in skin. Moreover, IMQ induced psoriasis mice model showed that M1/M2 polarization was altered in deficiency of CST. Furthermore, IMQ induced psoriasis model in CST-/-TNFR1-/- and CST-/-TNFR2-/- mice indicated the role of CST in skin inflammation might rely on interaction with TNFR1. Collectively, CST appears to regulate the polarization of M1/M2 in psoriasis-like skin inflammation via directly bind to TNFR1, which might provide a potential therapeutic target of psoriasis-like skin inflammation. Funding: This work was supported by the Key Research and Development Projects of Shandong Province (Grant No. 2015GSF118115 and 2019GSF108152), the Natural Science Foundation of Shandong Province (Grant No. BS2014YY048, BS2015SW028, ZR2019MH075, ZR2014HM101, and ZR2016HM53), the Cross-disciplinary Fund of Shandong University (Grant No. 2018JC007) and the National Natural Science Foundation of China (Grant No. 81501880 and 81602761). Declaration of Interest: None. Ethical Approval: All experiments concerning animals in this study were approved by the Institutional Animal Care and Use Committee of Shandong University, and performed according to the ARRIVE guideline.

RETRACTED: Overexpression of cortistatin alleviates oxygen/glucose-deprivation-induced ER stress and prompts neural stem cell proliferation via SSTR2

Cerebral infarction (CI), a blood circulatory disorder, causes a high mortality and disability rate worldwide. Intriguingly, a newly discovered neuropeptide, Cortistatin (CST), has been indicated to inhibit the cortical activity. In our research, we aimed to explore the functional relevance of CST in neural stem cells (NSCs) in CI rats. The expression of CST was determined in NSCs induced by oxygen-glucose deprivation (OGD). NSCs isolated from the embryonic rat brain were treated with OGD to establish an in vitro CI model while dithiothreitol (DTT) was introduced to induce endoplasmic reticulum stress (ERS), which were evaluated by assessment of GRP94, caspase-12 and CHOP expression. Then CST expression was restored by transfection of oe-CST, followed by assessment of NSC proliferation ability and cytotoxicity. Finally, the expression of CST and its receptor Somatostatin receptor subtype 2 (SSTR2) was quantified for mechanism exploration. CST was downregulated in CI, which was further confirmed in NSCs under OGD treatment. Overexpressed CST was found to promote cell activity and attenuate OGD-induced cytotoxicity of NSCs. Meanwhile, it was observed that the injured proliferation ability of NSCs was restored by CST overexpression. Besides, lower expression of GRP94, caspase-12 and CHOP was indicative of suppressed occurrence of ERS by CST. Mechanically, CST inhibited ERS through SSTR2. CST could facilitate the proliferation of NSCs in CI induced by OGD, ultimately highlighting a novel therapeutic target for CI treatment.