The plasma levels of CST and BCKDK in patients with sepsis

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

BACKGROUND

Although 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.

PURPOSE

The 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 RESULTS

In 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.

CONCLUSIONS

This 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.

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.

Serum Cortistatin Levels in Patients with Ocular Active and Ocular Inactive Behçet Disease

PURPOSE

To evaluate serum cortistatin (CST) levels in patients with ocular active and ocular inactive Behçet disease (BD) and its relationship with disease activity.

METHODS

24 BD patients with ocular active, 24 BD patients with ocular inactive patients and 24 healthy control subjects were included in the study.

RESULTS

In ocular active and ocular inactive BD patients and healthy control subjects, the mean serum CST levels were 4.38 ± 1.63ng/ml, 5.46 ± 1.81ng/ml and 7.56 ± 1.73ng/ml, respectively. ESR, serum CRP, CST levels and NLR were significantly different between the groups (p < 0.001 for all). The CST levels were similar between ocular active and inactive BD patient groups (p = 0.197). ESR, CRP and NLR were significantly higher in ocular active BD patients compared to ocular inactive BD patients and healthy control subjects (p < 0.05 for all).

CONCLUSION

Serum CST level was significantly lower in BD patients. CST may be a neuropeptide that plays a role in the pathogenesis of BD.

Cortistatin, a novel cardiovascular protective peptide

Cortistatin (CST) is a small molecule bioactive peptide containing an FWKT tetramer. It is widely distributed in nervous, immune and endocrine systems. Many studies have shown that CST can exert many biological effects, for example: regulating sleep, learning and memory processes, inducing immune tolerance, inhibiting inflammatory responses, and regulating endocrine metabolism. Notably, it is found that CST and its receptors are also widely distributed in the cardiovascular system, such as the aorta, coronary arteries and heart. In recent years, increasing studies have shown that CST played an important role in the development of cardiovascular diseases, such as reducing myocardial damage, inhibiting autoimmune myocarditis, alleviating vascular smooth muscle cell (VSMC) proliferation and migration, reducing vascular calcification (VC), and inhibiting atherosclerosis and aneurysm formation. Therefore, we reviewed the cardiovascular effects of CST in the heart and blood vessels, which will help to understand the role of CST and its receptors in the pathogenesis of cardiovascular diseases, and highlight novel strategies and targets for the prevention and treatment of cardiovascular diseases.

Circulating levels of cortistatin are correlated with metabolic parameters in patients with newly diagnosed type 2 diabetes mellitus

Cortistatin (CST) is a recently discovered cyclic neuropeptide with multiple bioactive effects. The aim of this study was to investigate the relationship between plasma CST and various metabolic markers in patients with newly diagnosed type 2 diabetes mellitus (T2DM). For this study, 60 patients with newly diagnosed T2DM and 38 age- and gender-matched healthy controls were recruited. Fasting plasma glucose (FPG), serum insulin and hemoglobin A_1c (HbA_1c) levels and a blood lipid profile were obtained with commercially available diagnostic reagents. CST plasma levels were determined using an enzyme immunoassay kit. The results showed that the plasma levels of CST were substantially lower in patients with newly diagnosed T2DM compared with the healthy controls. Plasma CST levels were positively correlated with high-density lipoprotein and negatively related to FPG, serum insulin, the homeostasis model assessment of insulin resistance (HOMA-IR) and HbA_1c in all subjects. Further analysis showed that CST levels were positively correlated with systolic blood pressure and negatively correlated with FPG, serum insulin, HOMA-IR and HbA_1c in patients with newly diagnosed T2DM. Moreover, logistic regression analyses indicated that plasma CST was correlated with newly diagnosed T2DM. In conclusion, patients with newly diagnosed T2DM had significantly lower plasma levels of CST than healthy controls, and plasma CST was associated with glucose metabolism and insulin resistance, indicating a potential role of CST in the development of T2DM.