Novel insights into the role of urotensin II in cardiovascular disease

Expanding Structure-Activity Relationships of Human Urotensin II Peptide Analogues: A Proposed Key Role of the N-Terminal Region for Novel Urotensin II Receptor Modulators

While the urotensinergic system plays a role in influencing various pathologies, its potential remains untapped because of the absence of therapeutically effective urotensin II receptor (UTR) modulators. Herein, we developed analogues of human urotensin II (hU-II) peptide in which, along with well-known antagonist-oriented modifications, the Glu1 residue was subjected to single-point mutations. The generated library was tested by a calcium mobilization assay and ex vivo experiments, also in competition with selected ligands. Interestingly, many derivatives showed noncompetitive modulation that was rationalized by the lateral allostery concept applied to a G protein-coupled receptor (GPCR) multimeric model. UPG-108 showed an unprecedented ability to double the efficacy of hU-II, while UPG-109 and UPG-111 turned out to be negative allosteric modulators of UTR. Overall, our investigation will serve to explore and highlight the expanding possibilities of modulating the UTR system through N-terminally modified hU-II analogues and, furthermore, will aim to elucidate the intricate nature of such a GPCR system.

Urantide alleviates atherosclerosis-related liver and kidney injury via the Wnt/β-catenin signaling pathway in ApoE(-/-) mice

OBJECTIVE

To investigate the role of urantide in the prevention and treatment of atherosclerosis (AS)-related liver and kidney injury by antagonizing the urotensin II/urotensin receptor (UII/UT) system and regulating the Wnt/β-catenin signaling pathway.

METHODS

Atherosclerotic ApoE-/- mice were treated with 20 mg/kg, 30 mg/kg, and 40 mg/kg urantide for 14 days.

RESULTS

When ApoE-/- mice developed AS, significant pathological changes occurred in the liver and kidney, and the UII/UT system in tissue was highly activated; furthermore, the Wnt/β-catenin signalling pathway was activated, and proteins related to this signalling pathway, such as GSK-3β, AXIN2, CK‑1, and APC, were significantly downregulated. After urantide treatment, the pathological damage to the liver and kidney was effectively improved, the activity of the UII/UT system was effectively inhibited, and the expression of the Wnt/β-catenin signalling pathway and related proteins was restored. Wnt/β-catenin signals were mainly localized in the cytoplasm, renal tubules, and interstitium.

CONCLUSION

Urantide could improve AS-related liver and kidney injury by antagonizing the UII/UT system, and the improvements in liver and kidney function in atherosclerotic ApoE-/- mice may be related to inhibition of the Wnt/β-catenin signalling pathway.

Sex-biased gene regulation varies across human populations as a result of adaptive evolution

OBJECTIVES

Studies of human sexual dimorphism and gender disparities in health focus on ostensibly universal molecular sex differences, such as sex chromosomes and circulating hormone levels, while ignoring the extraordinary diversity in biology, behavior, and culture acquired by different human populations over their unique evolutionary histories.

MATERIALS AND METHODS

Using RNA-Seq data and whole genome sequences from 1000G and HGDP, we investigate variation in sex-biased gene expression across 11 human populations and test whether population-level variation in sex-biased expression may have resulted from adaptive evolution in regions containing sex-specific regulatory variants.

RESULTS

We find that sex-biased gene expression in humans is highly variable, mostly population-specific, and demonstrates between population reversals. Expression quantitative trait locus mapping reveals sex-specific regulatory regions with evidence of recent positive natural selection, suggesting that variation in sex-biased expression may have evolved as an adaptive response to ancestral environments experienced by human populations.

DISCUSSION

These results indicate that sex-biased gene expression is more flexible than previously thought and is not generally shared among human populations. Instead, molecular phenotypes associated with sex depend on complex interactions between population-specific molecular evolution and physiological responses to contemporary socioecologies.

Interactome profiling of Crimean-Congo hemorrhagic fever virus glycoproteins

Crimean-Congo hemorrhagic fever virus (CCHFV) is a biosafety level-4 pathogen requiring urgent research and development efforts. The glycoproteins of CCHFV, Gn and Gc, are considered to play multiple roles in the viral life cycle by interactions with host cells; however, these interactions remain largely unclear to date. Here, we analyzed the cellular interactomes of CCHFV glycoproteins and identified 45 host proteins as high-confidence Gn/Gc interactors. These host molecules are involved in multiple cellular biological processes potentially associated with the physiological actions of the viral glycoproteins. Then, we elucidated the role of a representative cellular protein, HAX1. HAX1 interacts with Gn by its C-terminus, while its N-terminal region leads to mitochondrial localization. By the strong interaction, HAX1 sequestrates Gn to mitochondria, thus depriving Gn of its normal Golgi localization that is required for functional glycoprotein-mediated progeny virion packaging. Consistently, the inhibitory activity of HAX1 against viral packaging and hence propagation was further elucidated in the contexts of pseudotyped and authentic CCHFV infections in cellular and animal models. Together, the findings provide a systematic CCHFV Gn/Gc-cell protein-protein interaction map, but also unravel a HAX1/mitochondrion-associated host antiviral mechanism, which may facilitate further studies on CCHFV biology and therapeutic approaches.

Urotensin II promotes the proliferation and secretion of vascular endothelial growth factor in rat dermal papilla cells by activating the Wnt-β-catenin signaling pathway

Introduction. Urotensin II (U II) is a kind of active peptide with a variety of biological effects, such as promoting cell proliferation and endocrine effects. The aim of this study is to investigate the effect of urotensin II on the proliferation and secretion of vascular endothelial growth factor (VEGF) in cultured rat dermal papilla cells (DPCs), and to explore its molecular mechanism. Materials and Methods. We used the DPCs isolated from the thoracic aortas of Wistar-Kyoto rats to run the CCK8 and ELISA assay, RC-PCR and Western blotting techniques to identify the effect of Urotensin II on the proliferation and secretion of VEGF in DPCs, data were analyzed by one-way ANOVA or t-test. Results. U II can increase the mRNA expression of proliferation markers Ki67 and PCNA. In addition, the Wnt/β-catenin pathway was activated by U II, but Wnt inhibitor DKK1 reversed the effect of U II. Conclusions. U II promoted the proliferation and secretion of VEGF in rat DPCs through activation of the Wnt-β-catenin signaling pathway.

Activation of the urotensin-II receptor by remdesivir induces cardiomyocyte dysfunction

Remdesivir is an antiviral drug used for COVID-19 treatment worldwide. Cardiovascular side effects have been associated with remdesivir; however, the underlying molecular mechanism remains unknown. Here, we performed a large-scale G-protein-coupled receptor screening in combination with structural modeling and found that remdesivir is a selective, partial agonist for urotensin-II receptor (UTS2R) through the Gα_i/o-dependent AKT/ERK axis. Functionally, remdesivir treatment induced prolonged field potential and APD₉₀ in human induced pluripotent stem cell (iPS)-derived cardiomyocytes and impaired contractility in both neonatal and adult cardiomyocytes, all of which mirror the clinical pathology. Importantly, remdesivir-mediated cardiac malfunctions were effectively attenuated by antagonizing UTS2R signaling. Finally, we characterized the effect of 110 single-nucleotide variants in UTS2R gene reported in genome database and found four missense variants that show gain-of-function effects in the receptor sensitivity to remdesivir. Collectively, our study illuminates a previously unknown mechanism underlying remdesivir-related cardiovascular events and that genetic variations of UTS2R gene can be a potential risk factor for cardiovascular events during remdesivir treatment, which collectively paves the way for a therapeutic opportunity to prevent such events in the future.

Urotensin II can Induce Skeletal Muscle Atrophy Associated with Upregulating Ubiquitin-Proteasome System and Inhibiting the Differentiation of Satellite Cells in CRF Mice

Skeletal muscle wasting and atrophy is highly prevalent in chronic renal failure (CRF) and increases the risk of mortality. According to our previous study, we speculate that urotensin II (UII) can induce skeletal muscle atrophy by upregulating ubiquitin-proteasome system(UPS) in CRF. C2C12 mouse myoblast cells were differentiated into myotubes, and myotubes were exposed to different concentrations of UII. Myotube diameters, myosin heavy chain(MHC), p-Fxo03A, skeletal muscle-specific E3 ubiquitin ligases such as muscle RING finger 1 (MuRF1) and muscle atrophy F-box (MAFbx/atrogin1) were detected. Three animal models (the sham operation mice as normal control (NC) group, wild-type C57BL/6 mice with 5/6 nephrectomy (WT CRF) group, UII receptor gene knock out (UT KO) mice with 5/6 nephrectomy (UT KO CRF) group) were designed. Cross-sectional area (CSA) of skeletal muscle tissues in three animal models were measured, and western blot detected protein of UII, p-Fxo03A, MAFbx and MuRF1, and immunofluorescence assays explored the satellite cell marker of Myod1 and Pax7, and PCR arrays detected the muscle protein degradation genes, protein synthesis genes and the genes which were involved in muscle components. UII could decrease mouse myotube diameters, and upregulate dephosphorylated Fxo03A protein. MAFbx and MuRF1 were higher in WT CRF group than that in NC group, but after UII receptor gene was knocked out (UT KO CRF), their expressions were downregulated. UII could inhibit the expression of Myod1 but not Pax7 in animal study. We first demonstrate that skeletal muscle atrophy induced by UII associated with upregulating ubiquitin-proteasome system and inhibiting the differentiation of satellite cells in CRF mice.

Globular adiponectin-mediated vascular remodeling by affecting the secretion of adventitial-derived tumor necrosis factor-α induced by urotensin II

OBJECTIVES

In this study, we explored how adiponectin mediated urotensin II (UII)‍-induced tumor necrosis factor-‍α (TNF-‍α) and α‍-smooth muscle actin (α‍-SMA) expression and ensuing intracellular signaling pathways in adventitial fibroblasts (AFs).

METHODS

Growth-arrested AFs and rat tunica adventitia of vessels were incubated with UII and inhibitors of signal transduction pathways for 1‍‒‍24 h. The cells were then harvested for TNF-α receptor (TNF-‍α-R) messenger RNA (mRNA) and TNF-‍α protein expression determination by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Adiponectin and adiponectin receptor (adipoR) expression was measured by RT-PCR, quantitative real-time PCR (qPCR), immunohistochemical analysis, and cell counting kit-8 (CCK-8) cell proliferation experiments. We then quantified TNF-α and α-SMA mRNA and protein expression levels by qPCR and immunofluorescence (IF) staining. RNA interference (RNAi) was used to explore the function of the adipoR genes. To investigate the signaling pathway, we applied western blotting (WB) to examine phosphorylation of adenosine 5'-monophosphate (AMP)‍-activated protein kinase (AMPK). In vivo, an adiponectin (APN)‍-knockout (APN-KO) mouse model mimicking adventitial inflammation was generated to measure TNF-α and α‍-SMA expression by application of qPCR and IF, with the goal of gaining a comprehensive atlas of adiponectin in vascular remodeling.

RESULTS

In both cells and tissues, UII promoted TNF-α protein and TNF-α-R secretion in a dose- and time-dependent manner via Rho/protein kinase C (PKC) pathway. We detected marked expression of adipoR1, T-cadherin, and calreticulin as well as a moderate presence of adipoR2 in AFs, while no adiponectin was observed. Globular adiponectin (gAd) fostered the growth of AFs, and acted in concert with UII to induce α-SMA and TNF-α through the adipoR1/T-cadherin/calreticulin/AMPK pathway. In AFs, gAd and UII synergistically induced AMPK phosphorylation. In the adventitial inflammation model, APN deficiency up-regulated the expression of α-SMA, UII receptor (UT), and UII while inhibiting TNF-‍α expression.

CONCLUSIONS

From the results of our study, we can speculate that UII induces TNF‍-‍α protein and TNF-‍α‍-R secretion in AFs and rat tunica adventitia of vessels via the Rho and PKC signal transduction pathways. Thus, it is plausible that adiponectin is a major player in adventitial progression and could serve as a novel therapeutic target for cardiovascular disease administration.

Urotensin II level is elevated in inflammatory bowel disease patients

It was reported that the urotensin II (U-II) level in inflammatory bowel disease (IBD) patients are significantly higher than in controls. To provide future guidance for the management of cardiovascular risk factors in IBD patients, the sample size of the current study appears to be limited, and more clinical samples to compare U-II levels in IBD patients and controls are needed. This will clarify the possible roles of inflammation factors and related signaling pathways (like EPK1/2, NF-κB and Rho/ROCK) in the pathophysiology of IBD. Therefore, large multicenter studies should be done to confirm the findings and underlying mechanisms in the future.

Urotensin II induces activation of NLRP3 and pyroptosis through calcineurin in cardiomyocytes

Cell pyroptosis, a new type of programmed cell death, has been recently reported to play important roles in the development of cardiac remodeling. How cardiomyocyte pyroptosis is induced remains to be elucidated. Urotensin II (UII) has been known closely related to cardiac remodeling and the development of heart failure. Inhibition of UII receptors has been shown to be effective in the treatment of cardiac hypertrophy and remodeling. However, it is not clear whether UII might induce cardiomyocyte pyroptosis. We here examined the effect of UII treatment on pyroptosis in cultured cardiomyocytes. Treatment of cardiomyocyes of neonatal rats with UII (500 nmol/l) for 48 hours induced a significant pyroptosis as evidenced by not only increased cell death but also upregulated expression levels of NLR family pyrin domain containing 3 (NLRP3), caspase-1, IL-1β, IL-18 and gasdermin D (GMDSD)-N which are important markers for the identification of cell pyroptosis. All these pyroptosis responses induced by UII were abrogated by an inhibitor of NLRP3. Moreover, the antagonist of UII receptor, Urantide abolished UII- induced cardiomyocyte pyroptosis. Additionally, inhibition of calcineurin by cyclosporin A rather than that of CaMKII by KN93 suppressed the UII-upregulated expression levels of those pyroptosis markers. We therefore demonstrate that UII might induce cardiomyocyte pyroptosis through calcineurin.

Urotensin II Induces Cardiac Fibrosis through the TGF-β/Smad Signaling Pathway during the Development of Cardiac Hypertrophy

Myocardial fibrosis is an important pathological phenomenon of cardiac remodeling that is induced by hypertension, myocardial ischemia, valvular heart disease, hypertrophic cardiomyopathy, and other heart diseases and can progress to heart failure. Urotensin II (UII) is regarded as a cardiovascular autacoid/hormone that is not only the most potent vasoconstrictor in mammals but also involved in cardiac remodeling. However, the molecular mechanisms responsible for UII-induced cardiac fibrosis have not yet been fully elucidated. Therefore, we aimed to investigate the effect of UII on myocardial fibrosis in cardiac hypertrophy and the mechanism of UII-induced cardiac fibrosis. Cardiac tissue from mice subjected to Transverse aortic constriction (TAC) was collected. Cardiac hypertrophy, myocardial fibrosis, and the expression of UII protein were assessed using echocardiography and pathological and molecular biological analyses. The effect of UII on fibrosis was evaluated in UII-treated mice and isolated rat primary cardiac fibroblasts, and the results indicated that UII induced significant myocardial fibrosis and increases in the proliferation and fibrotic responses both in mice and cultured fibroblasts. Mechanistically, UII treatment induced activation of the TGF-β/Smad signaling pathway, which was suppressed by the UII receptor antagonist. In conclusion, UII plays critical roles in cardiac fibrosis by modulating the TGF-β/Smads signaling pathway, which may be a promising therapeutic target in hypertrophic cardiomyopathy and related problems, such as cardiac remodeling and heart failure.

Urotensin II levels in patients with inflammatory bowel disease

BACKGROUND

Patients with inflammatory bowel disease (IBD) are associated with increased cardiovascular risk and have increased overall cardiovascular burden. On the other hand, urotensin II (UII) is one of the most potent vascular constrictors with immunomodulatory effect that is connected with a number of different cardiometabolic disorders as well. Furthermore, patients with ulcerative colitis have shown increased expression of urotensin II receptor in comparison to healthy controls. Since the features of IBD includes chronic inflammation and endothelial dysfunction as well, it is plausible to assume that there is connection between increased cardiac risk in IBD and UII.

AIM

To determine serum UII levels in patients with IBD and to compare them to control subjects, as well as investigate possible associations with relevant clinical and biochemical parameters.

METHODS

This cross sectional study consecutively enrolled 50 adult IBD patients (26 with Crohn’s disease and 24 with ulcerative colitis) and 50 age and gender matched controls. Clinical assessment was performed by the same experienced gastroenterologist according to the latest guidelines. Ulcerative Colitis Endoscopic Index of Severity and Simple Endoscopic Score for Crohn’s Disease were used for endoscopic evaluation. Serum levels of UII were determined using the enzyme immunoassay kit for human UII, according to the manufacturer’s instructions.

RESULTS

IBD patients have significantly higher concentrations of UII when compared to control subjects (7.57 ± 1.41 vs 1.98 ± 0.69 ng/mL, P < 0.001), while there were no significant differences between Crohn’s disease and ulcerative colitis patients (7.49 ± 1.42 vs 7.65 ± 1.41 ng/mL, P = 0.689). There was a significant positive correlation between serum UII levels and high sensitivity C reactive peptide levels (r = 0.491, P < 0.001) and a significant negative correlation between serum UII levels and total proteins (r = -0.306, P = 0.032). Additionally, there was a significant positive correlation between serum UII levels with both systolic (r = 0.387, P = 0.005) and diastolic (r = 0.352, P = 0.012) blood pressure. Moreover, serum UII levels had a significant positive correlation with Ulcerative Colitis Endoscopic Index of Severity (r = 0.425, P = 0.048) and Simple Endoscopic Score for Crohn’s Disease (r = 0.466, P = 0.028) scores. Multiple linear regression analysis showed that serum UII levels retained significant association with high sensitivity C reactive peptide (β ± standard error, 0.262 ± 0.076, P < 0.001) and systolic blood pressure (0.040 ± 0.017, P = 0.030).

CONCLUSION

It is possible that UII is involved in the complex pathophysiology of cardiovascular complications in IBD patients, and its purpose should be investigated in further studies.

Dynamic Changes in Plasma Urotensin II and Its Correlation With Plaque Stability

ABSTRACT

Urotensin II (UII) is involved in the formation of atherosclerosis, but its role in the stability of atherosclerotic plaques is unknown. The purpose of this study was to observe the dynamic changes in plasma UII and analyze its relationship to the stability of atherosclerotic plaques. One hundred thirty-five consecutive patients with acute coronary syndrome (ACS) were enrolled. The plasma UII levels were measured immediately after admission and during three-month follow-up. A vulnerable plaque model was established using local transfection of a recombinant P53 adenovirus into plaques in rabbits fed with a high-cholesterol diet and subjected to balloon arterial injury. The levels of plasma UII were measured weekly. The changes in plasma UII during the formation of atherosclerotic plaques and before and after plaque transfection were observed. The morphology of the plaques and the expression, distribution, and quantitative expression of UII in the plaques also were observed. Our results showed that the levels of plasma UII in patients with ACS at admission were lower than levels observed at the three-month follow-up. UII dynamic changes and its correlation with plaque stabilities were further verified in rabbits with atherosclerotic vulnerable plaques. The UII levels in rabbits were significantly decreased immediately after the P53 gene transfection, which led to plaque instability and rupture. These results suggested that UII expression was down-regulated in ACS, which may be related to its ability to modulate mechanisms involved in plaque stability and instability.

Salidroside and isorhamnetin attenuate urotensin II-induced inflammatory response in vivo and in vitro: Involvement in regulating the RhoA/ROCK II pathway

Urotensin II (UII), a vital vasoconstrictor peptide, causes an inflammatory response in the pathogenesis of atherosclerosis. Previous studies have reported that the Ras homolog gene family, member A (RhoA)/Rho kinases (ROCK) pathway modulates the inflammatory response of the atherosclerotic process. However, to the best of our knowledge, whether the RhoA/ROCK pathway mediates the inflammatory effect of UII has not been previously elucidated. Salidroside and isorhamnetin are two early developed antioxidant Tibetan drugs, both displaying cardioprotective effects against atherosclerosis. Therefore, the aim of the present study was to investigate the protective effects of salidroside, isorhamnetin or combination of these two drugs on the UII-induced inflammatory response in vivo (rats) or in vitro [primary vascular smooth muscle cells (VSMCs)], as well as to examine the role of the RhoA/ROCK pathway in these processes. The levels of inflammatory markers were measured via ELISA. The mRNA and protein expression levels of RhoA and ROCK II were detected using reverse transcription-quantitative PCR assay and western blot analysis. It was demonstrated that salidroside, isorhamnetin and both in combination decreased the levels of the serum pro-inflammatory cytokines TNF-α and IL-1β, as well as increased the levels of the anti-inflammatory cytokine IL-10 and macrophage migration inhibitory factor in rats with subacute infusion of UII and in the culture supernatant from primary VSMCs-exposed to UII. Moreover, salidroside, isorhamnetin and both in combination attenuated the mRNA and protein expression levels of RhoA and ROCK II in vivo and in vitro, at concentrations corresponding to human therapeutic blood plasma concentrations. Thus, these drugs could inhibit the RhoA/ROCK II pathway under UII conditions. The combination of salidroside and isorhamnetin did not display a stronger inhibitory effect on the inflammatory response and the RhoA/ROCK II pathway compared with salidroside and isorhamnetin in isolation. Collectively, the results indicated that salidroside, isorhamnetin and both in combination inhibited the RhoA/ROCK II pathway, which then attenuated the inflammatory response under UII-induced conditions, resulting in cardioprotection in atherosclerosis.

Urantide attenuates myocardial damage in atherosclerotic rats by regulating the MAPK signalling pathway

OBJECTIVE

To explore the effect of urantide on atherosclerotic myocardial injury by antagonizing the urotensin II/urotensin II receptor (UII/UT) system and regulating the mitogen-activated protein kinase (MAPK) signalling pathway.

METHODS

Atherosclerosis (AS) was established in rats by administering a high-fat diet and an intraperitoneal injection of vitamin D₃. The effect of treatment with urantide (30 μg/kg), a UII receptor antagonist, for 3, 7, or 14 days on AS-induced myocardial damage was evaluated.

RESULTS

The heart of rats with AS exhibited pathological changes suggestive of myocardial injury, and the serum levels of creatine kinase (CK) and lactate dehydrogenase (LDH) were significantly increased. Additionally, significant increases in the levels of UII, its receptor (G protein-coupled receptor 14, GPR14), p-P38, p-extracellular signal-regulated kinase (ERK) and p-c-Jun N-terminal kinase (JNK) were observed in the heart. Urantide improved pathological changes in the heart of rats with AS and reduced the serum CK and LDH levels. Additionally, the UII antagonist decreased the increased levels of UII, GPR14, p-P38, p-ERK and p-JNK in the heart.

CONCLUSIONS

Urantide alleviates atherosclerotic myocardial injury by inhibiting the UII-GPR14 interaction and regulating the MAPK signalling pathway. We hypothesized that myocardial injury may be associated with the regulation of the MAPK signalling pathway.