Recombinant frizzled1 protein attenuated cardiac hypertrophy after myocardial infarction via the canonical Wnt signaling pathway

Chlorogenic Acid Attenuates Isoproterenol Hydrochloride-Induced Cardiac Hypertrophy in AC16 Cells by Inhibiting the Wnt/β-Catenin Signaling Pathway

Cardiac hypertrophy (CH) is an important characteristic in heart failure development. Chlorogenic acid (CGA), a crucial bioactive compound from honeysuckle, is reported to protect against CH. However, its underlying mechanism of action remains incompletely elucidated. Therefore, this study aimed to explore the mechanism underlying the protective effect of CGA on CH. This study established a CH model by stimulating AC16 cells with isoproterenol (Iso). The observed significant decrease in cell surface area, evaluated through fluorescence staining, along with the downregulation of CH-related markers, including atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and β-myosin heavy chain (β-MHC) at both mRNA and protein levels, provide compelling evidence of the protective effect of CGA against isoproterenol-induced CH. Mechanistically, CGA induced the expression of glycogen synthase kinase 3β (GSK-3β) while concurrently attenuating the expression of the core protein β-catenin in the Wnt/β-catenin signaling pathway. Furthermore, the experiment utilized the Wnt signaling activator IM-12 to observe its ability to modulate the impact of CGA pretreatment on the development of CH. Using the Gene Expression Omnibus (GEO) database combined with online platforms and tools, this study identified Wnt-related genes influenced by CGA in hypertrophic cardiomyopathy (HCM) and further validated the correlation between CGA and the Wnt/β-catenin signaling pathway in CH. This result provides new insights into the molecular mechanisms underlying the protective effect of CGA against CH, indicating CGA as a promising candidate for the prevention and treatment of heart diseases.

Functional small peptides for enhanced protein delivery, solubility, and secretion in microbial biotechnology

In microbial biotechnology, there is a constant demand for functional peptides to give new functionality to engineered proteins to address problems such as direct delivery of functional proteins into bacterial cells, enhanced protein solubility during the expression of recombinant proteins, and efficient protein secretion from bacteria. To tackle these critical issues, we selected three types of functional small peptides: cell-penetrating peptides (CPPs) enable the delivery of diverse cargoes into bacterial cytoplasm for a variety of purposes, protein-solubilizing peptide tags demonstrate remarkable efficiency in solubilizing recombinant proteins without folding interference, and signal peptides play a key role in enabling the secretion of recombinant proteins from bacterial cells. In this review, we introduced these three functional small peptides that offer effective solutions to address emerging problems in microbial biotechnology. Additionally, we summarized various engineering efforts aimed at enhancing the activity and performance of these peptides, thereby providing valuable insights into their potential for further applications.

Transcription factor EB (TFEB) improves ventricular remodeling after myocardial infarction by inhibiting Wnt/β-catenin signaling pathway

Background

Adverse left ventricular remodeling after myocardial infarction (MI) compromises cardiac function and increases heart failure risk. Until now, comprehension of the role transcription factor EB (TFEB) plays after MI is limited.

Objectives

The purpose of this study was to describe the effects of TFEB on fibroblasts differentiation and extracellular matrix expression after MI.

Methods

AAV9 (adeno-associated virus) mediated up- and down-regulated TFEB expressions were generated in C57BL/6 mice two weeks before the MI modeling. Echocardiography, Masson, Sirius red staining immunofluorescence, and wheat germ agglutinin staining were performed at 3 days, and 1, 2, and 4 weeks after MI modeling. Fibroblasts collected from SD neonatal rats were transfected by adenovirus and siRNA, and cell counting kit-8 (CCK8), immunofluorescence, wound healing and Transwell assay were conducted. Myocardial fibrosis-related proteins were identified by Western blot. PNU-74654 (100 ng/mL) was used for 12 hours to inhibit β-catenin-TCF/LEF1 complex.

Results

The up-regulation of TFEB resulted in reduced fibroblasts proliferation and its differentiation into myofibroblasts in vitro studies. A significant up-regulation of EF and down-regulation of myocyte area was shown in the AAV9-TFEB group. Meanwhile, decreased protein level of α-SMA and collagen I were observed in vitro study. TFEB didn't affect the concentration of β-catenin. Inhibition of TFEB, which promoted cell migration, proliferation and collagen I expression, was counteracted by PNU-74654.

Conclusions

TFEB demonstrated potential in restraining fibrosis after MI by inhibiting the Wnt/β-catenin signaling pathway.

Puerarin attenuates isoproterenol‑induced myocardial hypertrophy via inhibition of the Wnt/β‑catenin signaling pathway

Myocardial hypertrophy (MH) is an independent risk factor for cardiovascular disease, which in turn lead to arrhythmia or heart failure. Therefore, attention must be paid to formulation of therapeutic strategies for MH. Puerarin is a key bioactive ingredient isolated from Pueraria genera of plants that is beneficial for the treatment of MH. However, its molecular mechanism of action has not been fully determined. In the present study, 40 µM puerarin was demonstrated to be a safe dose for human AC16 cells using Cell Counting Kit‑8 assay. The protective effects of puerarin against MH were demonstrated in AC16 cells stimulated with isoproterenol (ISO). These effects were characterized by a significant decrease in surface area of cells (assessed using fluorescence staining) and mRNA and protein expression levels of MH‑associated biomarkers, including atrial and brain natriuretic peptide, assessed using reverse transcription‑quantitative PCR and western blotting, as well as β‑myosin heavy chain mRNA expression levels. Mechanistically, western blotting demonstrated that puerarin inhibited activation of the Wnt signaling pathway. Puerarin also significantly decreased phosphorylation of p65; this was mediated via crosstalk between the Wnt and NF‑κB signaling pathways. An inhibitor (Dickkopf‑1) and activator (IM‑12) of the Wnt signaling pathway were used to demonstrate that puerarin‑mediated effects alleviated ISO‑induced MH via the Wnt signaling pathway. The results of the present study demonstrated that puerarin pre‑treatment may be a potential therapeutic strategy for preventing ISO‑induced MH and managing MH in the future.

Brain vasculature disturbance in schizophrenia

PURPOSE OF REVIEW

The vascular hypothesis of schizophrenia (SZ) postulates that brain endothelial dysfunction contributes to brain pathophysiology. This review discusses recent evidence for and against this hypothesis, including data related to blood-brain barrier (BBB), brain endothelium, and brain blood supply, to provide a critical weighed update.

RECENT FINDINGS

Different studies report a consistent proportion of SZ patients showing increased BBB permeability, reflected by higher levels of albumin in the cerebral spinal fluid. Of note, this was not a result of antipsychotic medication. The high inflammatory profile observed in some SZ patients is strongly associated with increased BBB permeability to circulating immune cells, and with more severe cognitive deficiencies. Also, sex was found to interact with BBB integrity and permeability in SZ. The strongest independent genetic association with SZ has been identified in FZD1, a hypoxia-response gene that is 600-fold higher expressed in early development endothelium as compared to adult brain endothelium. Regarding brain blood supply, there is evidence to suggest alterations in proper brain perfusion in SZ. Nonetheless, ex-vivo experiments suggested that widely used antipsychotics favor vasoconstriction; thus, alterations in cerebral perfusion might be related to the patients' medication.

SUMMARY

In some patients with SZ, a vulnerable brain endothelium may be interacting with environmental stressors, such as inflammation or hypoxia, converging into a more severe SZ symptomatology. Gene expression and performance of human brain endothelium could vary along with development and the establishment of the BBB; therefore, we encourage to investigate its possible contribution to SZ considering this dynamic context.

Effect of Interventions in WNT Signaling on Healing of Cardiac Injury: A Systematic Review

The wound healing that follows myocardial infarction is a complex process involving multiple mechanisms, such as inflammation, angiogenesis and fibrosis. In the last two decades, the involvement of WNT signaling has been extensively studied and effects on virtually all aspects of this wound healing have been reported. However, as often is the case in a newly emerging field, inconsistent and sometimes even contradictory findings have been reported. The aim of this systematic review is to provide a comprehensive overview of studies in which the effect of interventions in WNT signaling were investigated in in vivo models of cardiac injury. To this end, we used different search engines to perform a systematic search of the literature using the key words "WNT and myocardial and infarction". We categorized the interventions according to their place in the WNT signaling pathway (ligand, receptor, destruction complex or nuclear level). The most consistent improvements of the wound healing response were observed in studies in which the acylation of WNT proteins was inhibited by administering porcupine inhibitors, by inhibiting of the downstream glycogen synthase kinase-3β (GSK3β) and by intervening in the β-catenin-mediated gene transcription. Interestingly, in several of these studies, evidence was presented for activation of cardiomyocyte proliferation around the infarct area. These findings indicate that inhibition of WNT signaling can play a valuable role in the repair of cardiac injury, thereby improving cardiac function and preventing the development of heart failure.

Circular RNA ITCH mediates H2O2-induced myocardial cell apoptosis by targeting miR-17-5p via wnt/β-catenin signalling pathway

Cardiovascular disease is a severe threat health worldwide, and circRNAs have been shown to be correlated with the development of cardiovascular disease. Expression of circ-ITCH and miR-17a-5p was evaluated by RT-qPCR. Cell viability was measured using CCK-8. Flow cytometry was applied to measure apoptosis rate. Binding between miR-17-5p and circ-ITCH was detected via luciferase reporter assays. Levels of ATP in cells were examined with ATP testing. Western blot was used to evaluate apoptosis-related proteins and proteins in Wnt/β-catenin signalling pathway. H2O2 induced apoptosis of H9c2 cells and lowered cell viability as well as ATP levels and circ-ITCH expression. After overexpression, circ-ITCH enhanced cell viability and ATP concentration. Meanwhile, apoptosis was inhibited. MiR-17-5p was the target of circ-ITCH as evidenced by luciferase report assays, with higher expression in H2O2-induced H9c2 cells. Knockdown of miR-17-5p could promote cell viability and level of ATP and curb apoptosis and p53 and PARP expression. Moreover, overexpressed miR-17-5p could reverse the function of upregulated circ-ITCH. Wnt3a, Wnt5a and β-catenin in Wnt/β-catenin signalling pathway were increased after H2O2 induction. Suppression of Wnt/β-catenin signalling pathway could initiate the process of injury in H9c2 cells. Circ-ITCH could protect myocardial cells from injuries caused by H2O2 by suppressing apoptosis while miR-17-5p played a reverse role, which could upregulate apoptosis and inhibit cell viability via Wnt/β-catenin signalling pathway.

Increased FGF23 protects against detrimental cardio-renal consequences during elevated blood phosphate in CKD

The phosphaturic hormone FGF23 is elevated in chronic kidney disease (CKD). The risk of premature death is substantially higher in the CKD patient population, with cardiovascular disease (CVD) as the leading mortality cause at all stages of CKD. Elevated FGF23 in CKD has been associated with increased odds for all-cause mortality; however, whether FGF23 is associated with positive adaptation in CKD is unknown. To test the role of FGF23 in CKD phenotypes, a late osteoblast/osteocyte conditional flox-Fgf23 mouse (Fgf23fl/fl/Dmp1-Cre+/-) was placed on an adenine-containing diet to induce CKD. Serum analysis showed casein-fed Cre+ mice had significantly higher serum phosphate and blood urea nitrogen (BUN) versus casein diet and Cre- genotype controls. Adenine significantly induced serum intact FGF23 in the Cre- mice over casein-fed mice, whereas Cre+ mice on adenine had 90% reduction in serum intact FGF23 and C-terminal FGF23 as well as bone Fgf23 mRNA. Parathyroid hormone was significantly elevated in mice fed adenine diet regardless of genotype, which significantly enhanced midshaft cortical porosity. Echocardiographs of the adenine-fed Cre+ hearts revealed profound aortic calcification and cardiac hypertrophy versus diet and genotype controls. Thus, these studies demonstrate that increased bone FGF23, although associated with poor outcomes in CKD, is necessary to protect against the cardio-renal consequences of elevated tissue phosphate.

The role of Wnt signaling in the healing myocardium: a focus on cell specificity

Various cell types are involved in the healing process after myocardial infarction (MI). Besides cardiac resident cells (such as cardiomyocytes, fibroblasts and endothelial cells) already present at the lesion site, a massive influx of leukocytes (mainly monocytes and neutrophils) is observed within hours after the ischemic event. So far, little is known about modes of interaction of these cells. Wnt signaling is an evolutionary conserved signaling cassette known to play an important role in cell-cell communication. While the overall reactivation of Wnt signaling upon ischemic injury is well described, the precise expression pattern of Wnt proteins, however, is far from understood. We here describe known Wnt components that partake in MI healing and differentiate cell-specific aspects. The secretion of Wnt proteins and their antagonists in the context of cardiac inflammation after MI appear to be tightly regulated in a spatial-temporal manner. Overall, we aim to stress the importance of elucidating not only Wnt component-specific aspects, but also their sometimes contradicting effects in different target cells. A better understanding of Wnt signaling in MI healing may eventually lead to the development of successful therapeutic approaches in an often considered "un-druggable" pathway.