Anti-Hair Loss Effect of Adenosine Is Exerted by cAMP Mediated Wnt/β-Catenin Pathway Stimulation via Modulation of Gsk3β Activity in Cultured Human Dermal Papilla Cells

In the present study, we investigated the molecular mechanisms of adenosine for its hair growth promoting effect. Adenosine stimulated the Wnt/β-catenin pathway by modulating the activity of Gsk3β in cultured human dermal papilla cells. It also activated adenosine receptor signaling, increasing intracellular cAMP level, and subsequently stimulating the cAMP mediated cellular energy metabolism. The phosphorylation of CREB, mTOR, and GSK3β was increased. Furthermore, the expression of β-catenin target genes such as Axin2, Lef1, and growth factors (bFGF, FGF7, IGF-1) was also enhanced. The inhibitor study data conducted in Wnt reporter cells and in cultured human dermal papilla cells demonstrated that adenosine stimulates Wnt/β-catenin signaling through the activation of the adenosine receptor and Gsk3β plays a critical role in transmitting the signals from the adenosine receptor to β-catenin, possibly via the Gαs/cAMP/PKA/mTOR signaling cascade.     

5-Bromo-3,4-dihydroxybenzaldehyde Promotes Hair Growth through Activation of Wnt/β-Catenin and Autophagy Pathways and Inhibition of TGF-β Pathways in Dermal Papilla Cells

Various studies addressing the increasing problem of hair loss, using natural products with few side effects, have been conducted. 5-bromo-3,4-dihydroxybenzaldehyde (BDB) exhibited anti-inflammatory effects in mouse models of atopic dermatitis and inhibited UVB-induced oxidative stress in keratinocytes. Here, we investigated its stimulating effect and the underlying mechanism of action on hair growth using rat vibrissa follicles and dermal papilla cells (DPCs), required for the regulation of hair cycle and length. BDB increased the length of hair fibers in rat vibrissa follicles and the proliferation of DPCs, along with causing changes in the levels of cell cycle-related proteins. We investigated whether BDB could trigger anagen-activating signaling pathways, such as the Wnt/β-catenin pathway and autophagy in DPCs. BDB induces activation of the Wnt/β-catenin pathway through the phosphorylation of GSG3β and β-catenin. BDB increased the levels of autophagic vacuoles and autophagy regulatory proteins Atg7, Atg5, Atg16L, and LC3B. We also investigated whether BDB inhibits the TGF-β pathway, which promotes transition to the catagen phase. BDB inhibited the phosphorylation of Smad2 induced by TGF-β1. Thus, BDB can promote hair growth by modulating anagen signaling by activating Wnt/β-catenin and autophagy pathways and inhibiting the TGF-β pathway in DPCs.     

Decreased expression of ATF3, orchestrated by β-catenin/TCF3, miR-17-5p and HOXA11-AS,promoted gastric cancer progression via increased β-catenin and CEMIP

ATF3 has been reported to be dysregulated in various cancers and involved in various steps of tumorigenesis. However, the mechanisms underlying the abnormal expression of ATF3 and its biological function in gastric cancer (GC) have not been well investigated. Here, we report ATF3 as one of the key regulators of GC development and progression. Patients with low ATF3 expression had shorter survival and a poorer prognosis. In vitro and in vivo assays investigating ATF3 alterations revealed a complex integrated phenotype that affects cell growth and migration. Strikingly, high-throughput sequencing and microarray analysis of cells with ATF3 silencing or of ATF3-low GC tissues indicated alterations in the Wnt signaling pathway, focal adhesions and adherens junctions. Mechanistically, the expression of β-catenin and cell migration inducing hyaluronidase 1 (CEMIP) was significantly upregulated in GC cells with downregulated ATF3, which was synergistically repressed by the β-catenin/TCF3 signaling axis and noncoding RNA miR-17-5p and HOXA11-AS. In addition, we found that WDR5 expression was promoted by TCF3 and is involved in miR-17-5p and HOXA11-AS activation in GC cells. Taken together, our findings revealed the mechanism of ATF3 downregulation and its biological role in regulating the expression of Wnt signaling-related genes during GC progression, suggesting new informative biomarkers of malignancy and therapeutic directions for GC patients.Subject terms: Gastric cancer, Experimental models of disease     

Emodin prevents intima thickness via Wnt4/Dvl-1/β-catenin signaling pathway mediated by miR-126 in balloon-injured carotid artery rats

Neointimal proliferation after vascular injury is a key mechanism of restenosis, a major cause of percutaneous transluminal angioplasty failure and artery bypass occlusion. Emodin, an anthraquinone with multiple physiological activities, has been reported to inhibit proliferation of vascular smooth muscle cells (VSMCs) that might cause intimal arterial thickening. Thus, in this study, we established a rat model of balloon-injured carotid artery and investigated the therapeutic effect of emodin and its underlying mechanism. Intimal thickness was analyzed by hematoxylin and eosin staining. Expression of Wnt4, dvl-1, β-catenin and collagen was determined by immunohistochemistry and/or western blotting. The proliferation of VSMC was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and electron microscopy. MicroRNA levels were quantified by real-time quantitative PCR. Emodin relieved injury-induced artery intimal thickness. Results of western blots and immunohistochemistry showed that emodin suppressed expression of signaling molecules Wnt4/Dvl-1/β-catenin as well as collagen protein in the injured artery. In addition, emodin enhanced expression of an artery injury-related microRNA, miR-126. In vitro, MTT assay showed that emodin suppressed angiotensin II (AngII)-induced proliferation of VSMCs. Emodin reversed AngII-induced activation of Wnt4/Dvl-1/β-catenin signaling by increasing expression of miR-126 that was strongly supported by transfection of mimic or inhibitor for miR-126. Emodin prevents intimal thickening via Wnt4/Dvl-1/β-catenin signaling pathway mediated by miR-126 in balloon-injured carotid artery of rats.     

The Wnt/β-catenin signaling pathway regulates the development of airway remodeling in patients with asthma

Airway remodeling is a key characteristic of chronic asthma, particularly in patients with a fixed airflow limitation. The mechanisms underlying airway remodeling are poorly understood, and no therapeutic option is available. The Wnt/β-catenin signaling pathway is involved in various physiological and pathological processes, including fibrosis and smooth muscle hypertrophy. In this study, we investigated the roles of Wnt/β-catenin signaling in airway remodeling in patients with asthma. Wnt7a mRNA expression was prominent in induced sputum from patients with asthma compared with that from healthy controls. Next, we induced a chronic asthma mouse model with airway remodeling features, including subepithelial fibrosis and airway smooth muscle hyperplasia. Higher expression of Wnt family proteins and β-catenin was detected in the lung tissue of mice with chronic asthma compared to control mice. Blocking β-catenin expression with a specific siRNA attenuated airway inflammation and airway remodeling. Decreased subepithelial fibrosis and collagen accumulation in the β-catenin siRNA-treated mice was accompanied by reduced expression of transforming growth factor-β. We further showed that suppressing β-catenin in the chronic asthma model inhibited smooth muscle hyperplasia by downregulating the tenascin C/platelet-derived growth factor receptor pathway. Taken together, these findings demonstrate that the Wnt/β-catenin signaling pathway is highly expressed and regulates the development of airway remodeling in chronic asthma.     

Cancer-associated fibroblast-secreted exosomal miR-423-5p promotes chemotherapy resistance in prostate cancer by targeting GREM2 through the TGF-β signaling pathway

Therapeutic failure in prostate cancer (PC) is believed to result from its unusually invasive and metastatic nature. Cancer-associated fibroblasts (CAFs) are essential in the tumor microenvironment. We intended to study the role of CAF-derived exosomes in the context of PC and the potential regulatory mechanism associated with miR-423-5p and GREM2. CAF-derived exosomes decreased the chemosensitivity of parental PC cells and enhanced the drug resistance of drug-resistant cells. PC-associated fibroblast-derived exosomes carrying miR-423-5p increased the resistance of PC to taxane by inhibiting GREM2 through the TGF-β pathway. Inhibition of the TGF-β pathway partially reversed the increased drug resistance in PC cells induced by CAF-derived exosomes. Inhibition of miR-423-5p enhanced the drug sensitivity of PC cells in vivo. We showed that CAF-secreted exosomal miR-423-5p promoted chemotherapy resistance in PC by targeting GREM2 through the TGF-β pathway. This study may allow the development of novel approaches for PC.Subject terms: Cancer, Cancer     

Euodia sutchuenensis Dode extract stimulates osteoblast differentiation via Wnt/β-catenin pathway activation

The Wnt/β-catenin pathway has a role in osteoblast differentiation and bone formation. We screened 100 plant extracts and identified an extract from Euodia sutchuenensis Dode (ESD) leaf and young branch as an effective activator of the Wnt/β-catenin pathway. ESD extract increased β-catenin levels and β-catenin nuclear accumulation in murine primary osteoblasts. The ESD extract also increased mRNA levels of osteoblast markers, including RUNX2, BMP2 and COL1A1, and enhanced alkaline phosphatase (ALP) activity in murine primary osteoblasts. Both ESD extract-induced β-catenin increment and ALP activation were abolished by β-catenin knockdown, confirming that the Wnt/β-catenin pathway functions in osteoblast differentiation. ESD extract enhanced terminal osteoblast differentiation as shown by staining with Alizarin Red S and significantly increased murine calvarial bone thickness. This study shows that ESD extract stimulates osteoblast differentiation via the Wnt/β-catenin pathway and enhances murine calvarial bone formation ex vivo.     

Activation of Hair Cell Growth Factors by Linoleic Acid in Malva verticillata Seed

Hair loss by excessive stress from work and lifestyle changes has become a growing concern, particularly among young individuals. However, most drugs for alopecia impose a plethora of side effects. We have found the powerful impact of Malva verticillata seed extracts on alleviating hair loss. This study further isolated effective chemicals in M. verticillata seed extracts by liquid silica gel column chromatography. Under the screening for the growth rate (%) of human follicles dermal papilla cells (HFDPCs), we identified linoleic acid (LA) and oleic acid in n-hexane of M. verticillate (MH)2 fraction. LA treatment activated Wnt/β-catenin signaling and induced HFDPCs growth by increasing the expression of cell cycle proteins such as cyclin D1 and cyclin-dependent kinase 2. LA treatment also increased several growth factors, such as vascular endothelial growth factor, insulin-like growth factor-1, hepatocyte growth factor, and keratinocyte growth factor, in a dose-dependent manner. Besides, LA significantly inhibited Dickkopf-related protein expression (DKK-1), a primary alopecia signaling by dihydrotestosterone. Our findings suggest that LA treatment may alleviate a testosterone-induced signaling molecule and induces HFDPCs growth by activating Wnt/β-catenin signaling.     

Negative feedback regulation of Wnt signaling by G�¦�-mediated reduction of Dishevelled

Wnt signaling is known to be important for diverse embryonic and post-natal cellular events and be regulated by the proteins Dishevelled and Axin. Although Dishevelled is activated by Wnt and involved in signal transduction, it is not clear how Dishevelled-mediated signaling is turned off. We report that guanine nucleotide binding protein beta 2 (Gnb2; Gβ₂) bound to Axin and Gβ₂ inhibited Wnt mediated reporter activity. The inhibition involved reduction of the level of Dishevelled, and the Gβ₂γ₂ mediated reduction of Dishevelled was countered by increased expression of Axin. Consistent with these effects in HEK293T cells, injection of Gβ₂γ₂ into Xenopus embryos inhibited the formation of secondary axes induced either by XWnt8 or Dishevelled, but not by β-catenin. The DEP domain of Dishevelled is necessary for both interaction with Gβ_2γ2 and subsequent degradation of Dishevelled via the lysosomal pathway. Signaling induced by Gβ_2γ2 is required because a mutant of Gβ₂, Gβ₂ (W332A) with lower signaling activity, had reduced ability to downregulate the level of Dishevelled. Activation of Wnt signaling by either of two methods, increased Frizzled signaling or transient transfection of Wnt, also led to increased degradation of Dishevelled and the induced Dishevelled loss is dependent on Gβ₁ and Gβ₂. Other studies with agents that interfere with PLC action and calcium signaling suggested that loss of Dishevelled is mediated through the following pathway: Wnt/Frizzled→Gβγ→PLC→Ca⁺²/PKC signaling. Together the evidence suggests a novel negative feedback mechanism in which Gβ₂γ₂ inhibits Wnt signaling by degradation of Dishevelled.     

Topical Nano Clove/Thyme Gel against Genetically Identified Clinical Skin Isolates: In Vivo Targeting Behavioral Alteration and IGF-1/pFOXO-1/PPAR γ Cues

Antimicrobial resistance is a dramatic global threat; however, the slow progress of new antibiotic development has impeded the identification of viable alternative strategies. Natural antioxidant-based antibacterial approaches may provide potent therapeutic abilities to effectively block resistance microbes’ pathways. While essential oils (EOs) have been reported as antimicrobial agents, its application is still limited ascribed to its low solubility and stability characters; additionally, the related biomolecular mechanisms are not fully understood. Hence, the study aimed to develop a nano-gel natural preparation with multiple molecular mechanisms that could combat bacterial resistance in an acne vulgaris model. A nano-emulgel of thyme/clove EOs (NEG8) was designed, standardized, and its antimicrobial activity was screened in vitro and in vivo against genetically identified skin bacterial clinical isolates (Pseudomonas stutzeri, Enterococcus faecium and Bacillus thuringiensis). As per our findings, NEG8 exhibited bacteriostatic and potent biofilm inhibition activities. An in vivo model was also established using the commercially available therapeutic, adapalene in contra genetically identified microorganism. Improvement in rat behavior was reported for the first time and NEG8 abated the dermal contents/protein expression of IGF-1, TGF-β/collagen, Wnt/β-catenin, JAK2/STAT-3, NE, 5-HT, and the inflammatory markers; p(Ser536) NF-κBp65, TLR-2, and IL-6. Moreover, the level of dopamine, protective anti-inflammatory cytokine, IL-10 and PPAR-γ protein were enhanced, also the skin histological structures were improved. Thus, NEG8 could be a future potential topical clinical alternate to synthetic agents, with dual merit mechanism as bacteriostatic antibiotic action and non-antibiotic microbial pathway inhibitor.     

Design and Synthesis of New Benzo[d]oxazole-Based Derivatives and Their Neuroprotective Effects on β-Amyloid-Induced PC12 Cells

A series of novel synthetic substituted benzo[d]oxazole-based derivatives (5a–5v) exerted neuroprotective effects on β-amyloid (Aβ)-induced PC12 cells as a potential approach for the treatment of Alzheimer’s disease (AD). In vitro studies show that most of the synthesized compounds were potent in reducing the neurotoxicity of Aβ_25-35-induced PC12 cells at 5 μg/mL. We found that compound 5c was non-neurotoxic at 30 μg/mL and significantly increased the viability of Aβ_25-35-induced PC12 cells at 1.25, 2.5 and 5 μg/mL. Western blot analysis showed that compound 5c promoted the phosphorylation of Akt and glycogen synthase kinase (GSK-3β) and decreased the expression of nuclear factor-κB (NF-κB) in Aβ_25-35-induced PC12 cells. In addition, our findings demonstrated that compound 5c protected PC12 cells from Aβ_25-35-induced apoptosis and reduced the hyperphosphorylation of tau protein, and decreased the expression of receptor for AGE (RAGE), β-site amyloid precursor protein (APP)-cleaving enzyme 1 (BACE1), inducible nitric oxide synthase (iNOS) and Bcl-2-associated X protein/B-cell lymphoma 2 (Bax/Bcl-2) via Akt/GSK-3β/NF-κB signaling pathway. In vivo studies suggest that compound 5c shows less toxicity than donepezil in the heart and nervous system of zebrafish.