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1.
Stem Cell Rev Rep ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38713406

ABSTRACT

Although stem/progenitor cell therapy shows potential for myocardial infarction repair, enhancing the therapeutic efficacy could be achieved through additional genetic modifications. HCLS1-associated protein X-1 (HAX1) has been identified as a versatile modulator responsible for cardio-protective signaling, while its role in regulating stem cell survival and functionality remains unknown. In this study, we investigated whether HAX1 can augment the protective potential of Sca1+ cardiac stromal cells (CSCs) for myocardial injury. The overexpression of HAX1 significantly increased cell proliferation and conferred enhanced resistance to hypoxia-induced cell death in CSCs. Mechanistically, HAX1 can interact with Mst1 (a prominent conductor of Hippo signal transduction) and inhibit its kinase activity for protein phosphorylation. This inhibition led to enhanced nuclear translocation of Yes-associated protein (YAP) and activation of downstream therapeutic-related genes. Notably, HAX1 overexpression significantly increased the pro-angiogenic potential of CSCs, as demonstrated by elevated expression of vascular endothelial growth factors. Importantly, implantation of HAX1-overexpressing CSCs promoted neovascularization, protected against functional deterioration, and ameliorated cardiac fibrosis in ischemic mouse hearts. In conclusion, HAX1 emerges as a valuable and efficient inducer for enhancing the effectiveness of cardiac stem or progenitor cell therapeutics.

2.
Can J Physiol Pharmacol ; 102(1): 1-13, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37903419

ABSTRACT

Cardiovascular diseases remain a leading cause of hospitalization affecting approximately 38 million people worldwide. While pharmacological and revascularization techniques can improve the patient's survival and quality of life, they cannot help reversing myocardial infarction injury and heart failure. Direct reprogramming of somatic cells to cardiomyocyte and cardiac progenitor cells offers a new approach to cellular reprogramming and paves the way for translational regenerative medicine. Direct reprogramming can bypass the pluripotent stage with the potential advantage of non-immunogenic cell products, reduced carcinogenic risk, and no requirement for embryonic tissue. The process of directly reprogramming cardiac cells was first achieved through the overexpression of transcription factors such as GATA4, MEF2C, and TBX5. However, over the past decade, significant work has been focused on enhancing direct reprogramming using a mixture of transcription factors, microRNAs, and small molecules to achieve cardiac cell fate. This review discusses the evolution of direct reprogramming, recent progress in achieving efficient cardiac cell fate conversion, and describes the reprogramming mechanisms at a molecular level. We also explore various viral and non-viral delivery methods currently being used to aid in the delivery of reprogramming factors to improve efficiency. However, further studies will be needed to overcome molecular and epigenetic barriers to successfully achieve translational cardiac regenerative therapeutics.


Subject(s)
Cellular Reprogramming Techniques , Quality of Life , Humans , Cellular Reprogramming Techniques/methods , Myocytes, Cardiac , Cellular Reprogramming , Transcription Factors/genetics , Regenerative Medicine/methods , Fibroblasts
3.
Curr Drug Targets ; 24(13): 1055-1065, 2023.
Article in English | MEDLINE | ID: mdl-37861037

ABSTRACT

BACKGROUND: Viaminate, a vitamin A acid drug developed in China, has been clinically used in acne treatment to regulate epithelial cell differentiation and proliferation, inhibit keratinization, reduce sebum secretion, and control immunological and anti-inflammatory actions; however, the exact method by which it works is unknown. METHODS: In the present study, acne was induced in the ears of rats using Propionibacterium acnes combined with sebum application. RESULTS: After 30 days of treatment with viaminate, the symptoms of epidermal thickening and keratin overproduction in the ears of rats were significantly improved. Transcriptomic analysis of rat skin tissues suggested that viaminate significantly regulated the biological pathways of cellular keratinization. Gene differential analysis revealed that the S100A8 and S100A9 genes were significantly downregulated after viaminate treatment. The results of qPCR and Western blotting confirmed that viaminate inhibited the expression of S100A8 and S100A9 genes and proteins in rat and HaCat cell acne models, while its downstream pathway MAPK (MAPK p38/JNK/ERK1/2) protein expression levels were suppressed. Additional administration of the S100A8 and S100A9 complex protein significantly reversed the inhibitory effect of viaminate on abnormal proliferation and keratinization levels in acne cell models. CONCLUSION: In summary, viaminate can improve acne by modulating S100A8 and S100A9 to inhibit MAPK pathway activation and inhibit keratinocyte proliferation and keratinization levels.


Subject(s)
Acne Vulgaris , Skin Neoplasms , Rats , Animals , Humans , MAP Kinase Signaling System , HaCaT Cells/metabolism , Propionibacterium acnes/metabolism , Calgranulin B/genetics , Calgranulin B/metabolism , Calgranulin B/pharmacology , Tretinoin/metabolism , Tretinoin/pharmacology , Acne Vulgaris/drug therapy , Cell Differentiation , Cell Proliferation
4.
Front Neurosci ; 17: 1212049, 2023.
Article in English | MEDLINE | ID: mdl-37397450

ABSTRACT

Introduction: The human brain processes shape and texture information separately through different neurons in the visual system. In intelligent computer-aided imaging diagnosis, pre-trained feature extractors are commonly used in various medical image recognition methods, common pre-training datasets such as ImageNet tend to improve the texture representation of the model but make it ignore many shape features. Weak shape feature representation is disadvantageous for some tasks that focus on shape features in medical image analysis. Methods: Inspired by the function of neurons in the human brain, in this paper, we proposed a shape-and-texture-biased two-stream network to enhance the shape feature representation in knowledge-guided medical image analysis. First, the two-stream network shape-biased stream and a texture-biased stream are constructed through classification and segmentation multi-task joint learning. Second, we propose pyramid-grouped convolution to enhance the texture feature representation and introduce deformable convolution to enhance the shape feature extraction. Third, we used a channel-attention-based feature selection module in shape and texture feature fusion to focus on the key features and eliminate information redundancy caused by feature fusion. Finally, aiming at the problem of model optimization difficulty caused by the imbalance in the number of benign and malignant samples in medical images, an asymmetric loss function was introduced to improve the robustness of the model. Results and conclusion: We applied our method to the melanoma recognition task on ISIC-2019 and XJTU-MM datasets, which focus on both the texture and shape of the lesions. The experimental results on dermoscopic image recognition and pathological image recognition datasets show the proposed method outperforms the compared algorithms and prove the effectiveness of our method.

5.
Nutrients ; 15(9)2023 May 02.
Article in English | MEDLINE | ID: mdl-37432375

ABSTRACT

The gut microbiome plays an essential role in regulating lipid metabolism. However, little is known about how gut microbiome modulates sex differences in lipid metabolism. The present study aims to determine whether gut microbiota modulates sexual dimorphism of lipid metabolism in mice fed a high-fat diet (HFD). Conventional and germ-free male and female mice were fed an HFD for four weeks, and lipid absorption, plasma lipid profiles, and apolipoprotein levels were then evaluated. The gut microbiota was analyzed by 16S rRNA gene sequencing. After 4-week HFD consumption, the females exhibited less body weight gain and body fat composition and significantly lower triglyceride levels in very-low-density lipoprotein (VLDL) and cholesterol levels in high-density lipoprotein (HDL) compared to male mice. The fecal microbiota analysis revealed that the male mice were associated with reduced gut microbial diversity. The female mice had considerably different microbiota composition compared to males, e.g., enriched growth of beneficial microbes (e.g., Akkermansia) and depleted growth of Adlercreutzia and Enterococcus. Correlation analyses suggested that the different compositions of the gut microbiota were associated with sexual dimorphism in body weight, fat mass, and lipid metabolism in mice fed an HFD. Our findings demonstrated significant sex differences in lipid metabolism and the microbiota composition at baseline (during LFD), along with sex-dependent responses to HFD. A comprehensive understanding of sexual dimorphism in lipid metabolism modulated by microbiota will help to develop more sex-specific effective treatment options for dyslipidemia and metabolic disorders in females.


Subject(s)
Gastrointestinal Microbiome , Female , Male , Animals , Mice , Sex Characteristics , Diet, High-Fat/adverse effects , Lipid Metabolism , RNA, Ribosomal, 16S/genetics , Body Weight , Lipoproteins, HDL
6.
bioRxiv ; 2023 Apr 24.
Article in English | MEDLINE | ID: mdl-37131709

ABSTRACT

Ischemia-reperfusion (I/R) injury is a common occurrence in various surgical procedures used to treat heart diseases. However, the role of insulin-like growth factor 2 receptor (IGF2R) during the process of myocardial I/R remains unclear. Therefore, this study aims to investigate the expression, distribution, and functionality of IGF2R in various I/R-associated models (such as reoxygenation, revascularization, and heart transplant). Loss-of-function studies (including myocardial conditional knockout and CRISPR interference) were performed to clarify the role of IGF2R in I/R injuries. Following hypoxia, IGF2R expression increased, but this effect was reversed upon restoration of oxygen levels. Loss of myocardial IGF2R was found to enhance the cardiac contractile functions, and reduced cell infiltration or cardiac fibrosis of I/R mouse models compared to the genotype control. CRISPR-inhibition of IGF2R decreased cell apoptotic death under hypoxia. RNA sequencing analysis indicated that myocardial IGF2R played a critical role in regulating the inflammatory response, innate immune response, and apoptotic process following I/R. Integrated analysis of the mRNA profiling, pulldown assays, and mass spectrometry identified granulocyte-specific factors as potential targets of myocardial IGF2R in the injured heart. In conclusion, myocardial IGF2R emerges as a promising therapeutic target to ameliorate inflammation or fibrosis following I/R injuries.

7.
Sci Rep ; 13(1): 3384, 2023 02 28.
Article in English | MEDLINE | ID: mdl-36854764

ABSTRACT

Vitiligo is the most common depigmenting disorder to which both genetic and environmental factors contribute. The aim of the current work was to evaluate the relationship between polymorphisms of the gene nuclear receptor subfamily 1 Group H member 3 (NR1H3) and the risk of vitiligo and phototherapy effects in the Chinese Han population. Two independent samples were enrolled to form the discovery set (comprised of 1668 nonsegmental vitiligo [NSV] patients and 2542 controls) and the validation set (comprised of 745 NSV patients and 1492 controls). A total of 13 tag single nucleotide polymorphisms (SNPs) were genotyped in the samples from the discovery stage. SNPs that achieved nominal significance were validated in another independent sample set. The serum level of NR1H3 protein was assayed using enzyme-linked immunosorbent assay kits in the validation set. Genetic association analysis was carried out at allelic and genotypic levels. The therapeutic effects of significant SNPs were examined in the validation set. The SNP rs3758672 was significantly associated with NSV. The A allele was correlated with NSV risk and poorer therapeutic effects. The A allele was strongly correlated with the increased level of serum NR1H3 in both controls and patients. In summary, SNP rs3758672 in NR1H3 was significantly associated with both disease susceptibility and individualized therapeutic effects of NSV in study participants with Han Chinese ancestry.


Subject(s)
Hypopigmentation , Ultraviolet Therapy , Vitiligo , Humans , Vitiligo/genetics , Vitiligo/radiotherapy , Polymorphism, Single Nucleotide , Alleles , Liver X Receptors
8.
Naunyn Schmiedebergs Arch Pharmacol ; 396(7): 1487-1500, 2023 07.
Article in English | MEDLINE | ID: mdl-36757484

ABSTRACT

Viaminate, a retinoic acid derivative developed in China, has been clinically used for acne treatment to regulate and control keratinocyte cell differentiation and proliferation, inhibit keratinization, reduce sebum secretion, and regulate immune and anti-inflammatory functions; however, its potential molecular mechanism has not yet been elucidated. Therefore, we induced ear acne in rats using Propionibacterium acnes and sebum application. Symptoms of ear redness, epidermal thickening, inflammatory reaction, keratin overproduction, subcutaneous oil, and triglyceride (TG) accumulation improved significantly in acne model rats treated with viaminate for 30 days. Transcriptome analysis of rat skin tissues suggested that viaminate had significant regulatory effects on fatty acid metabolism and cellular keratinization pathways. Molecular target prediction suggested that toll-like receptor 2 (TLR2) may be a key target of viaminate's therapeutic mechanism. Western blotting results confirmed that viaminate inhibited the TLR2 and its downstream pathways, nuclear factor-kappa B (NF-κB) [NF-κB inhibitor alpha (IκBα)/NF-κB-p65] and mitogen-activated protein kinases (MAPKs) [MAPK p38/c-Jun N-terminal kinase (JNK)/extracellular regulated kinase 1/2 (ERK1/2)] in acne vulgaris rats. In vitro studies revealed that viaminate treatment attenuated P. acnes proliferation and P. acnes-induced inflammatory response in human keratinocytes and has an inhibitory effect on the activation of NF-κB and MAPKs, while overexpression of TLR2 attenuated these effects. In conclusion, viaminate ameliorates P. acnes-induced acne by inhibiting the proliferation and inflammatory response of keratinocytes, ascribed to the deactivation of the TLR2-mediated NF-κB and MAPK pathways.


Subject(s)
Acne Vulgaris , NF-kappa B , Rats , Humans , Animals , NF-kappa B/metabolism , Propionibacterium acnes/metabolism , Toll-Like Receptor 2 , Tretinoin , Acne Vulgaris/drug therapy , Acne Vulgaris/metabolism , Mitogen-Activated Protein Kinases
9.
Cells ; 11(9)2022 05 07.
Article in English | MEDLINE | ID: mdl-35563879

ABSTRACT

We demonstrated previously that extracellular vesicles (EVs) released from mesenchymal stem cells (MSCs) play a critical role in angiogenesis. Here, we examine whether this pro-angiogenic efficacy is enhanced in EVs derived from MSCs overexpressing GATA-4 (MSCGATA-4). Methods and Results. EVs were isolated from MSCGATA-4 (EVGATA-4) and control MSCs transduced with an empty vector (EVnull). EVs from both cell types were of the same size and displayed similar molecular markers. Compared with EVnull, EVGATA-4 increased both a tube-like structure formation and spheroid-based sprouting of human umbilical vein endothelial cells (HUVECs). The EVGATA-4 increased the numbers of CD31-positive cells and hemoglobin content inside Matrigel plugs subcutaneously transplanted into mice for 2 weeks. Moreover, EVGATA-4 encapsulated higher levels of let-7 family miRs compared to EVnull. The transfer of exosomal let-7 miRs into HUVECs was recorded with an accompanied down-regulation of thrombospondin-1 (THBS1) expression, a major endogenous angiogenesis inhibitor. The loss-and-gain of function studies of let-7 miRs showed that let-7f knockdown significantly decreased EVGATA-4-mediated vascularization inside Matrigel plugs. In contrast, let-7f overexpression promoted HUVEC migration and tube formation. Conclusion. Our results indicate that EVs derived from genetically modified MSCs with GATA-4 overexpression had increased pro-angiogenic capacity due to the delivery of let-7 miRs that targeted THBS1 in endothelial cells.


Subject(s)
Extracellular Vesicles , Mesenchymal Stem Cells , MicroRNAs , Animals , Extracellular Vesicles/metabolism , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Mesenchymal Stem Cells/metabolism , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Neovascularization, Pathologic/metabolism
10.
Nanotechnology ; 33(24)2022 Mar 23.
Article in English | MEDLINE | ID: mdl-35235919

ABSTRACT

In this study, we developed a flexible and transparent silver/polystyrene/polydimethylsiloxane (Ag/PS/PDMS) substrate with both high density of hot spots and satisfactory uniformity using a cost-effective approach. Via template-guided self-assembly, PS beads were arranged regularly in nanobowls of a square array on PDMS, whose surface structure was transferred from a commercial complementary metal oxide semiconductor chip. Roughness was introduced onto the PS bead surface by nitrogen plasma treatment, followed by sputtering of Ag which generated many hot spots. Differential roughness on the PS bead surface greatly influenced the morphology of the Ag/PS/PDMS substrate. A meat-ball like surface structure was formed with a plasma etching time of 5 min, whose growth mechanism was proposed based on the scanning electron microscope analysis. The high sensitivity and desirable uniformity of the meat-ball like Ag/PS/PDMS substrate were demonstrated by using crystal violet as a Raman reporter, exhibiting an enhancement factor of 2.7 × 107and a relative standard deviation of 5.04%. Thiram of a lower concentration than the maximum residue limit on the cucumber surface could easily be detectedin situby the proposed substrate, demonstrating its great potential forin-situfood safety analysis.

11.
Genes (Basel) ; 13(2)2022 01 30.
Article in English | MEDLINE | ID: mdl-35205322

ABSTRACT

The sequential meal pattern has recently received more attention because it reflects a phycological diet style for human beings. The present study investigated the effects of the second lipid meal on lymphatic lipid absorption and transport in adult rats following a previous lipid meal. Using the well-established lymph fistula model, we found that the second lipid meal significantly increased the lymphatic output of triglycerides, cholesterol, phospholipids, and non-esterified fatty acids compared with a single lipid meal. Besides that, the time reaching the peak of each lipid output was significantly faster compared with the first lipid meal. Additionally, the second lipid meal significantly increased the lymphatic output of apolipoprotein A-IV (ApoA-IV), but not apolipoprotein B-48 (ApoB-48) or apolipoprotein A-I (ApoA-I). Interestingly, the triglyceride/apoB-48 ratio was significantly increased after the second lipid meal, indicating the increased chylomicron size in the lymph. Finally, the second lipid meal increased the lymphatic output of rat mucosal mast cell protease II (RMCPII). No change was found in the expression of genes related to the permeability of lymphatic lacteals, including vascular endothelial growth factor-A (Vegfa), vascular endothelial growth factor receptor 1 (Flt1), and Neuropilin1 (Nrp1). Collectively, the second lipid meal led to the rapid appearance of bigger-sized chylomicrons in the lymph. It also increased the lymphatic output of various lipids and apoA-IV, and mucosal mast cell activity in the intestine.


Subject(s)
Apolipoproteins A , Vascular Endothelial Growth Factor A , Animals , Apolipoprotein B-48 , Chylomicrons/metabolism , Meals , Rats , Triglycerides/metabolism
12.
Mol Ther ; 30(1): 54-74, 2022 01 05.
Article in English | MEDLINE | ID: mdl-34678511

ABSTRACT

Fibroblasts can be reprogrammed into cardiovascular progenitor cells (CPCs) using transgenic approaches, although the underlying mechanism remains unclear. We determined whether activation of endogenous genes such as Gata4, Nkx2.5, and Tbx5 can rapidly establish autoregulatory loops and initiate CPC generation in adult extracardiac fibroblasts using a CRISPR activation system. The induced fibroblasts (>80%) showed phenotypic changes as indicated by an Nkx2.5 cardiac enhancer reporter. The progenitor characteristics were confirmed by colony formation and expression of cardiovascular genes. Cardiac sphere induction segregated the early and late reprogrammed cells that can generate functional cardiomyocytes and vascular cells in vitro. Therefore, they were termed CRISPR-induced CPCs (ciCPCs). Transcriptomic analysis showed that cell cycle and heart development pathways were important to accelerate CPC formation during the early reprogramming stage. The CRISPR system opened the silenced chromatin locus, thereby allowing transcriptional factors to access their own promoters and eventually forming a positive feedback loop. The regenerative potential of ciCPCs was assessed after implantation in mouse myocardial infarction models. The engrafted ciCPCs differentiated into cardiovascular cells in vivo but also significantly improved contractile function and scar formation. In conclusion, multiplex gene activation was sufficient to drive CPC reprogramming, providing a new cell source for regenerative therapeutics.


Subject(s)
Clustered Regularly Interspaced Short Palindromic Repeats , Myocardial Infarction , Animals , Cell Differentiation/genetics , Cellular Reprogramming/genetics , Fibroblasts/metabolism , Mice , Myocardial Infarction/genetics , Myocardial Infarction/metabolism , Myocardial Infarction/therapy , Myocytes, Cardiac/metabolism , Stem Cells/metabolism
13.
Cells ; 10(7)2021 07 15.
Article in English | MEDLINE | ID: mdl-34359955

ABSTRACT

The functionalization of decellularized scaffolds is still challenging because of the recellularization-related limitations, including the finding of the most optimal kind of cell(s) and the best way to control their distribution within the scaffolds to generate native mimicking tissues. That is why researchers have been encouraged to study stem cells, in particular, mesenchymal stem cells (MSCs), as alternative cells to repopulate and functionalize the scaffolds properly. MSCs could be obtained from various sources and have therapeutic effects on a wide range of inflammatory/degenerative diseases. Therefore, in this mini-review, we will discuss the benefits using of MSCs for recellularization, the factors affecting their efficiency, and the drawbacks that may need to be overcome to generate bioengineered transplantable organs.


Subject(s)
Extracellular Matrix/metabolism , Mesenchymal Stem Cells/cytology , Stem Cells/cytology , Tissue Scaffolds , Animals , Cell Differentiation , Humans , Tissue Engineering/methods
14.
J Invest Dermatol ; 141(11): 2710-2719.e6, 2021 11.
Article in English | MEDLINE | ID: mdl-34029575

ABSTRACT

Vitiligo shows insufficient response to current therapies largely owing to T-lymphocyte dysfunction, abnormal inflammatory activation, and excessive oxidative stress in lesions. Cold atmospheric plasma (CAP) possesses pleiotropic antioxidant and anti-inflammatory properties and may offer an improvement to current treatment options. In this study, the efficacy and safety of CAP were investigated in a mouse model of vitiligo and a randomized and controlled trial of patients with active focal vitiligo. Skin biopsies showed that topical treatment of vitiligo-like lesions on mouse dorsal skin by CAP restored the distribution of melanin. In addition, CAP treatment reduced the infiltration of CD11c+ dendritic cells, CD3+ T cells, and CD8+ T cells; inhibited the release of CXCL10 and cytokine IFN-γ; and enhanced cellular resistance to oxidative stress and excessive immune response by enhancing the expression of the transcription factor NRF2 and attenuating the activity of inducible nitric oxide synthase. In a randomized and controlled trial, CAP treatment achieved partial and complete repigmentation in 80% and 20% of vitiligo lesions, respectively, without hyperpigmentation in surrounding areas or other adverse events during the treatment period and its follow-up period. In conclusion, CAP offers a promising option for the management of vitiligo.


Subject(s)
Hydrogels/therapeutic use , Plasma Gases/therapeutic use , Vitiligo/therapy , Adolescent , Adult , Aged , Animals , CD8-Positive T-Lymphocytes/immunology , Chemokine CXCL10/analysis , Child , Disease Models, Animal , Female , Humans , Male , Mice, Inbred C57BL , Middle Aged , Nitric Oxide Synthase Type II/physiology , Oxidative Stress , Vitiligo/immunology , Vitiligo/metabolism , Vitiligo/pathology , Young Adult
15.
Exp Biol Med (Maywood) ; 246(7): 851-860, 2021 04.
Article in English | MEDLINE | ID: mdl-33327780

ABSTRACT

Heart transplantation continues to be the gold standard clinical intervention to treat patients with end-stage heart failure. However, there are major complications associated with this surgical procedure that reduce the survival prognosis of heart transplant patients, including allograft rejection, malignancies, infections, and other complications that arise from the use of broad-spectrum immunosuppression drugs. Recent studies have demonstrated the use of mesenchymal stem cells (MSCs) against allotransplantation rejection in both in vitro and in vivo settings due to their immunomodulatory properties. Therefore, utilization of MSCs provides new and exciting strategies to improve heart transplantation and potentially reduce the use of broad-spectrum immunosuppression drugs while alleviating allograft rejection. In this review, we will discuss the current research on the mechanisms of cardiac allograft rejection, the physiological and immunological characteristics of MSCs, the effects of MSCs on the immune system, and immunomodulation of heart transplantation by MSCs.


Subject(s)
Allografts/immunology , Graft Rejection/immunology , Heart Transplantation , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/cytology , Animals , Heart Transplantation/methods , Humans , Immunosuppression Therapy/methods , Mesenchymal Stem Cell Transplantation/methods , Mesenchymal Stem Cells/immunology
17.
Front Med (Lausanne) ; 8: 775587, 2021.
Article in English | MEDLINE | ID: mdl-35071264

ABSTRACT

Malignant melanoma (MM) recognition in whole-slide images (WSIs) is challenging due to the huge image size of billions of pixels and complex visual characteristics. We propose a novel automatic melanoma recognition method based on the multi-scale features and probability map, named MPMR. First, we introduce the idea of breaking up the WSI into patches to overcome the difficult-to-calculate problem of WSIs with huge sizes. Second, to obtain and visualize the recognition result of MM tissues in WSIs, a probability mapping method is proposed to generate the mask based on predicted categories, confidence probabilities, and location information of patches. Third, considering that the pathological features related to melanoma are at different scales, such as tissue, cell, and nucleus, and to enhance the representation of multi-scale features is important for melanoma recognition, we construct a multi-scale feature fusion architecture by additional branch paths and shortcut connections, which extracts the enriched lesion features from low-level features containing more detail information and high-level features containing more semantic information. Fourth, to improve the extraction feature of the irregular-shaped lesion and focus on essential features, we reconstructed the residual blocks by a deformable convolution and channel attention mechanism, which further reduces information redundancy and noisy features. The experimental results demonstrate that the proposed method outperforms the compared algorithms, and it has a potential for practical applications in clinical diagnosis.

18.
Genes (Basel) ; 11(12)2020 12 12.
Article in English | MEDLINE | ID: mdl-33322656

ABSTRACT

Estradiol (E2) enhances the anorectic action of apolipoprotein A-IV (apoA-IV), however, the intracellular mechanisms are largely unclear. Here we reported that the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway was significantly activated by E2 and apoA-IV, respectively, in primary neuronal cells isolated from rat embryonic brainstem. Importantly, the combination of E2 and apoA-IV at their subthreshold doses synergistically activated the PI3K/Akt signaling pathway. These effects, however, were significantly diminished by the pretreatment with LY294002, a selective PI3K inhibitor. E2-induced activation of the PI3K/Akt pathway was through membrane-associated ERα, because the phosphorylation of Akt was significantly increased by PPT, an ERα agonist, and by E2-BSA (E2 conjugated to bovine serum albumin) which activates estrogen receptor on the membrane. Centrally administered apoA-IV at a low dose (0.5 µg) significantly suppressed food intake and increased the phosphorylation of Akt in the nucleus tractus solitarius (NTS) of ovariectomized (OVX) rats treated with E2, but not in OVX rats treated with vehicle. These effects were blunted by pretreatment with LY294002. These results indicate that E2's regulatory role in apoA-IV's anorectic action is through the ERα-PI3K pathway in the NTS. Manipulation of the PI3K/Akt signaling activation in the NTS may provide a novel therapeutic approach for the prevention and the treatment of obesity-related disorders in females.


Subject(s)
Anorexia , Apolipoproteins A/pharmacology , Estradiol/pharmacology , Estrogen Receptor alpha/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction/drug effects , Solitary Nucleus , Animals , Anorexia/chemically induced , Anorexia/metabolism , Anorexia/pathology , Female , Rats , Rats, Long-Evans , Solitary Nucleus/metabolism , Solitary Nucleus/pathology
19.
Genes (Basel) ; 11(11)2020 10 29.
Article in English | MEDLINE | ID: mdl-33137935

ABSTRACT

BACKGROUND: We demonstrated that the transduction of Wnt11 into mesenchymal stem cells (MSCs) (MSCWnt11) promotes these cells differentiation into cardiac phenotypes. In the present study, we investigated the paracrine effects of MSCWnt11 on cardiac function and angiogenesis. METHODS AND RESULTS: Conditioned medium was collected from MSCWnt11 (CdMWnt11) and their control cells (CdMGFP). CdMWnt11, especially obtained from MSCWnt11 exposed to hypoxia, significantly promoted human umbilical vein endothelial cells (HUVECs) migration and increased capillary-like tube (CLT) formation, which was blocked by Wnt11 neutralizing antibody. Wnt11 protein was significantly higher in CdMWnt11 compared to that in CdMGFP. Directly treating HUVECs with recombinant Wnt11 protein significantly increased CLT formation, which was abrogated by treating cells with the JNK inhibitor SP600125, as well as the PKC inhibitor Calphostin-C. Moreover, the transfection of Wnt11 to HUVECs (HWnt11) significantly increased CLT formation and HUVEC migration, as well as upregulated p-pan-PKC and p-JNK expression. Injection of CdMWnt11 into the peri-infarct region in a rat acute myocardial infarction (AMI) model significantly improved cardiac function, reduced infarct size, and increased myocardial blood flow and blood vessel density in the ischemic area. CONCLUSION: Wnt11 released from MSCWnt11 increased angiogenesis and improved cardiac function via non-canonical Wnt-PKC-JNK dependent pathways.


Subject(s)
Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Neovascularization, Physiologic , Wnt Proteins/metabolism , Wnt Signaling Pathway , Animals , Capillaries/cytology , Capillaries/growth & development , Capillaries/metabolism , Cells, Cultured , Culture Media, Conditioned , Disease Models, Animal , Female , Human Umbilical Vein Endothelial Cells , Humans , MAP Kinase Signaling System , Myocardial Infarction/metabolism , Myocardial Infarction/physiopathology , Neovascularization, Physiologic/genetics , Protein Kinase C/metabolism , Rats , Rats, Sprague-Dawley , Rats, Transgenic , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Wnt Proteins/antagonists & inhibitors , Wnt Proteins/genetics , Wnt Signaling Pathway/genetics
20.
Stem Cells Int ; 2019: 3726392, 2019.
Article in English | MEDLINE | ID: mdl-31814833

ABSTRACT

Cardiac stem cell therapy offers the potential to ameliorate postinfarction remodeling and development of heart failure but requires optimization of cell-based approaches. Cardiac progenitor cells (CPCs) induction by ISX-9, a small molecule possessing antioxidant, prosurvival, and regenerative properties, represents an attractive potential approach for cell-based cardiac regenerative therapy. Here, we report that extracellular vesicles (EV) secreted by ISX-9-induced CPCs (EV-CPCISX-9) faithfully recapitulate the beneficial effects of their parent CPCs with regard to postinfarction remodeling. These EV contain a distinct repertoire of biologically active miRNAs that promoted angiogenesis and proliferation of cardiomyocytes while ameliorating fibrosis in the infarcted heart. Amongst the highly enriched miRNAs, miR-373 was strongly antifibrotic, targeting 2 key fibrogenic genes, GDF-11 and ROCK-2. miR-373 mimic itself was highly efficacious in preventing scar formation in the infarcted myocardium. Together, these novel findings have important implications with regard to prevention of postinfarction remodeling.

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