Mechanism of action and in vivo role of platelet-derived growth factor

Clinical observations and mechanistic insights of traditional Chinese medicine in the management of diabetic retinopathy

CONTEXT

Diabetic retinopathy (DR) is one of the leading causes of vision impairment and blindness among diabetic patients globally. Despite advancements in conventional treatments, the quest for more holistic approaches and fewer side effects persists. Traditional Chinese medicine (TCM) has been used for centuries in managing various diseases, including diabetes and its complications.

OBJECTIVE

This review evaluated the efficacy and underlying mechanisms of TCM in the management of DR, providing information on its potential integration with conventional treatment methods.

METHODS

A comprehensive literature review was conducted using PubMed, Web of Science, and the China National Knowledge Infrastructure (CNKI) with the search terms 'traditional Chinese medicine', 'diabetic retinopathy', 'clinical efficacies' and their combinations. Studies published before 2023 without language restriction were included, focusing on clinical trials and observational studies that assessed the effectiveness of TCM in DR treatment.

RESULTS

The review synthesized evidence of empirical traditional Chinese formulas, traditional Chinese patent medicines, and isolated phytochemicals on DR treatment. The key mechanisms identified included the reduction of oxidative stress, inflammation, and neovascularization, as well as the improvement in neurovascular functionality and integrity of the retinal blood barrier.

CONCLUSIONS

TCM shows promising potential to manage DR. More large-scale, randomized controlled trials are recommended to validate these findings and facilitate the integration of TCM into mainstream DR treatment protocols.

MicroRNA miR-145-5p Inhibits Cutaneous Wound Healing by Targeting PDGFD in Diabetic Foot Ulcer

Diabetic foot ulcer (DFU) is one major, common and serious chronic complication of diabetes mellitus, which is characterized by high incidence, high risk, high burden, and high treatment difficulty and is a leading cause of disability and death in patients with diabetes. Long-term hyperglycemia can result in cellular dysfunction of fibroblasts, which play pivotal roles in wound healing. MicroRNAs (miRNAs) were reported to mediate the pathological processes of multiple diseases, including diabetic wound healing. This research aimed to investigate the functional role of miR-145-5p in high-glucose (HG)-exposed fibroblasts and in DFU mouse models. Human foreskin fibroblast cells (HFF-1) were stimulated by HG to induce cell injury. MiR-145-5p level in HG-stimulated HFF-1 cells was detected via RT-qPCR. The binding between miR-145-5p and PDGFD was validated by Luciferase reporter assay. The effects of the miR-145-5p/PDGFD axis on the viability, migration, and apoptosis of HG-exposed HFF-1 cells were determined by CCK-8, wound healing, and flow cytometry assays. DFU mouse models were subcutaneously injected at the wound edges with miR-145-5p inhibitor/mimics. Images of the wounds were captured on day 0 and 8 post-injection, and wound samples were collected after mice were sacrificed for histological analysis by H&E staining. HG decreased cell viability and increased miR-145-5p expression in HFF-1 cells in a dose- and time-dependent manner. MiR-145-5p downregulation promoted cell viability and migration and inhibited cell apoptosis of HG-stimulated HFF-1 cells, while miR-145-5p overexpression exerted an opposite effect on cell viability, migration, and apoptosis. PDGFD was a direct target gene of miR-145-5p, whose silencing reversed the influence of miR-145-5p downregulation on HG-induced cellular dysfunction of HFF-1 cells. Additionally, downregulating miR-145-5p facilitated while overexpressing miR-145-5p inhibited wound healing in DFU mouse models. MiR-145-5p level was negatively associated with PDGFD level in wound tissue samples of DFU mouse models. MiR-145-5p inhibition improves wound healing in DFU through upregulating PDGFD expression.

Molecular immunological mechanisms of impaired wound healing in diabetic foot ulcers (DFU), current therapeutic strategies and future directions

Diabetic foot ulcer (DFU) is a foremost cause of amputation in diabetic patients. Consequences of DFU include infections, decline in limb function, hospitalization, amputation, and in severe cases, death. Immune cells including macrophages, regulatory T cells, fibroblasts and other damage repair cells work in sync for effective healing and in establishment of a healthy skin barrier post-injury. Immune dysregulation during the healing of wounds can result in wound chronicity. Hyperglycemic conditions in diabetic patients influence the pathophysiology of wounds by disrupting the immune system as well as promoting neuropathy and ischemic conditions, making them difficult to heal. Chronic wound microenvironment is characterized by increased expression of matrix metalloproteinases, reactive oxygen species as well as pro-inflammatory cytokines, resulting in persistent inflammation and delayed healing. Novel treatment modalities including growth factor therapies, nano formulations, microRNA based treatments and skin grafting approaches have significantly augmented treatment efficiency, demonstrating creditable efficacy in clinical practices. Advancements in local treatments as well as invasive methodologies, for instance formulated wound dressings, stem cell applications and immunomodulatory therapies have been successful in targeting the complex pathophysiology of chronic wounds. This review focuses on elucidating the intricacies of emerging physical and non-physical therapeutic interventions, delving into the realm of advanced wound care and comprehensively summarizing efficacy of evidence-based therapies for DFU currently available.

Variations of VEGFR2 Chemical Space: Stimulator and Inhibitory Peptides

The kinase pathway plays a crucial role in blood vessel function. Particular attention is paid to VEGFR type 2 angiogenesis and vascular morphogenesis as the tyrosine kinase pathway is preferentially activated. In silico studies were performed on several peptides that affect VEGFR2 in both stimulating and inhibitory ways. This investigation aims to examine the molecular properties of VEGFR2, a molecule primarily involved in the processes of vasculogenesis and angiogenesis. These relationships were defined by the interactions between Vascular Endothelial Growth Factor receptor 2 (VEGFR2) and the structural features of the systems. The chemical space of the inhibitory peptides and stimulators was described using topological and energetic properties. Furthermore, chimeric models of stimulating and inhibitory proteins (for VEGFR2) were computed using the protein system structures. The interaction between the chimeric proteins and VEGFR was computed. The chemical space was further characterized using complex manifolds and high-dimensional data visualization. The results show that a slightly similar chemical area is shared by VEGFR2 and stimulating and inhibitory proteins. On the other hand, the stimulator peptides and the inhibitors have distinct chemical spaces.

Healing the diabetic wound: Unlocking the secrets of genes and pathways

Diabetic wounds (DWs) are open sores that can occur anywhere on a diabetic patient's body. They are often complicated by infections, hypoxia, oxidative stress, hyperglycemia, and reduced growth factors and nucleic acids. The healing process involves four phases: homeostasis, inflammation, proliferation, and remodeling, regulated by various cellular and molecular events. Numerous genes and signaling pathways such as VEGF, TGF-β, NF-κB, PPAR-γ, MMPs, IGF, FGF, PDGF, EGF, NOX, TLR, JAK-STAT, PI3K-Akt, MAPK, ERK, JNK, p38, Wnt/β-catenin, Hedgehog, Notch, Hippo, FAK, Integrin, and Src pathways are involved in these events. These pathways and genes are often dysregulated in DWs leading to impaired healing. The present review sheds light on the pathogenesis, healing process, signaling pathways, and genes involved in DW. Further, various therapeutic strategies that target these pathways and genes via nanotechnology are also discussed. Additionally, clinical trials on DW related to gene therapy are also covered in the present review.

Immunohistochemical analysis of PDGFR-α for wound age determination

Immunohistochemical analysis of platelet-derived growth factor receptor-α (PDGFR-α) was performed on human skin wounds obtained from forensic autopsy cases. Thirty human skin wounds were collected at different post-infliction intervals as follows: Group I, 4 h to 3 days (n = 16); Group II, 4 to 7 days (n = 7); Group III, 9 to 10 days (n = 3); and Group IV, 14 to 20 days (n = 4). Immunopositive reactions for PDGFR-α were not observed in the uninjured human skin specimens. In a semi-quantitative morphometrical analysis, the number of PDGFR-α-positive cells was observed increased in Group II, with the average number of PDGFR-α-positive cells being the highest in Group II. Additionally, in Group II, all specimens showed PDGFR-α-positive cells, with an average number of > 200 cells in five fields of view, suggesting a wound age of 4 to 7 days. Taken together, the immunohistochemical detection of PDGFR-α in human skin wounds can be a useful tool for wound age determination.

Yohimbine Inhibits PDGF-Induced Vascular Smooth Muscle Cell Proliferation and Migration via FOXO3a Factor

Yohimbine (YHB) has been reported to possess anti-inflammatory, anticancer, and cardiac function-enhancing properties. Additionally, it has been reported to inhibit the proliferation, migration, and neointimal formation of vascular smooth muscle cells (VSMCs) induced by platelet-derived growth factor (PDGF) stimulation by suppressing the phospholipase C-gamma 1 pathway. However, the transcriptional regulatory mechanism of YHB controlling the behavior of VSMCs is not fully understood. In this study, YHB downregulated the expression of cell cycle regulatory proteins, such as proliferating cell nuclear antigen (PCNA), cyclin D1, cyclin-dependent kinase 4 (CDK4), and cyclin E, by modulating the transcription factor FOXO3a in VSMCs induced by PDGF. Furthermore, YHB decreased p-38 and mTOR phosphorylation in a dose-dependent manner. Notably, YHB significantly reduced the phosphorylation at Y397 and Y925 sites of focal adhesion kinase (FAK), and this effect was greater at the Y925 site than Y397. In addition, the expression of paxillin, a FAK-associated protein known to bind to the Y925 site of FAK, was significantly reduced by YHB treatment in a dose-dependent manner. A pronounced reduction in the migration and proliferation of VSMCs was observed following co-treatment of YHB with mTOR or p38 inhibitors. In conclusion, this study shows that YHB inhibits the PDGF-induced proliferation and migration of VSMCs by regulating the transcription factor FOXO3a and the mTOR/p38/FAK signaling pathway. Therefore, YHB may be a potential therapeutic candidate for preventing and treating cardiovascular diseases such as atherosclerosis and vascular restenosis.

Defining the Role of Oral Pathway Inhibitors as Targeted Therapeutics in Arteriovenous Malformation Care

Arteriovenous malformations (AVMs) are vascular malformations that are prone to rupturing and can cause significant morbidity and mortality in relatively young patients. Conventional treatment options such as surgery and endovascular therapy often are insufficient for cure. There is a growing body of knowledge on the genetic and molecular underpinnings of AVM development and maintenance, making the future of precision medicine a real possibility for AVM management. Here, we review the pathophysiology of AVM development across various cell types, with a focus on current and potential druggable targets and their therapeutic potentials in both sporadic and familial AVM populations.

Recent advances and future directions on small molecule VEGFR inhibitors in oncological conditions

"A journey of mixed emotions" is a quote that best describes the progress chart of vascular endothelial growth factor receptor (VEGFR) inhibitors as cancer therapeutics in the last decade. Exhilarated with the Food and Drug Administration (FDA) approvals of numerous VEGFR inhibitors coupled with the annoyance of encountering the complications associated with their use, drug discovery enthusiasts are on their toes with an unswerving determination to enhance the rate of translation of VEGFR inhibitors from preclinical to clinical stage. The recently crafted armory of VEGFR inhibitors is a testament to their growing dominance over other antiangiogenic therapies for cancer treatment. This review perspicuously underscores the earnest attempts of the researchers to extract the antiproliferative potential of VEGFR inhibitors through the design of mechanistically diverse structural assemblages. Moreover, this review encompasses sections on structural/molecular properties and physiological functions of VEGFR, FDA-approved VEGFR inhibitors, and hurdles restricting the activity range/clinical applicability of VEGFR targeting antitumor agents. In addition, tactics to overcome the limitations of VEGFR inhibitors are discussed. A clear-cut viewpoint transmitted through this compilation can provide practical directions to push the cart of VEGFR inhibitors to advanced-stage clinical investigations in diverse malignancies.

Mitogen-Activated Protein Kinases Mediate Adventitial Fibroblast Activation and Neointima Formation via GATA4/Cyclin D1 Axis

PURPOSE

Activation of mitogen-activated protein kinases (MAPKs) by pathological stimuli participates in cardiovascular diseases. Dysfunction of adventitial fibroblast has emerged as a critical regulator in vascular remodeling, while the potential mechanism remains unclear. In this study, we sought to determine the effect of different activation of MAPKs in adventitial fibroblast contributing to neointima formation.

METHODS

Balloon injury procedure was performed in male 12-week-old Sprague-Dawley rats. After injury, MAPK inhibitors were applied to the adventitia of injured arteries to suppress MAPK activation. Adventitial fibroblasts were stimulated by platelet-derived growth factor-BB (PDGF-BB) with or without MAPK inhibitors. RNA sequencing was performed to investigate the change of pathway and cell function. Wound healing, transwell assay, and flow cytometry were used to analyze adventitial fibroblast function.

RESULTS

Phosphorylation of p38, c-Jun N-terminal kinase (JNK), and extracellular regulated kinases 1/2 (ERK1/2) was increased in injured arteries after balloon injury. In primary culture of adventitial fibroblasts, PDGF-BB increased phosphorylation of p38, JNK, ERK1/2, and extracellular regulated kinase 5 (ERK5) in a short time, which was normalized by their inhibitors respectively. Compared with the injury group, perivascular administration of four MAPK inhibitors significantly attenuated neointima formation by quantitative analysis of neointimal area, intima to media (I/M) ratio, and lumen area. RNA sequencing of adventitial fibroblasts treated with PDGF-BB with or without four inhibitors demonstrated differentially expressed genes involved in multiple biological processes, including cell adhesion, proliferation, migration, and inflammatory response. Wound healing and transwell assays showed that four inhibitors suppressed PDGF-BB-induced adventitial fibroblast migration. Cell cycle analysis by flow cytometry demonstrated that JNK, ERK1/2, and ERK5 but not p38 inhibitor blocked PDGF-BB-induced G1 phase release associated with decrease expression of cell cycle protein Cyclin D1 and transcription factor GATA4. Moreover, four inhibitors decreased macrophage infiltration into adventitia and monocyte chemoattractant protein-1 (MCP-1) expression.

CONCLUSION

These results suggest that MAPKs differentially regulate activation of adventitial fibroblast through GATA4/Cyclin D1 axis that participates in neointima formation.

Vertical Intrauterine Bovine and Ovine Papillomavirus Coinfection in Pregnant Cows

There is very little information available about transplacental infections by the papillomavirus in ruminants. However, recent evidence has emerged of the first report of vertical infections of bovine papillomavirus (BPV) in fetuses from naturally infected, pregnant cows. This study reports the coinfection of BPV and ovine papillomavirus (OaPV) in bovine fetuses from infected pregnant cows suffering from bladder tumors caused by simultaneous, persistent viral infections. Some molecular mechanisms involving the binary complex composed of Eras and platelet-derived growth factor β receptor (PDGFβR), by which BPVs and OaPVs contribute to reproductive disorders, have been investigated. A droplet digital polymerase chain reaction (ddPCR) was used to detect and quantify the nucleic acids of the BPVs of the Deltapapillomavirus genus (BPV1, BPV2, BPV13, and BPV14) and OaPVs belonging to the Deltapapillomavirus (OaPV1, OaPV2, and OaPV4) and Dyokappapapillomavirus (OaPV3) genera in the placenta and fetal organs (heart, lung, liver, and kidneys) of four bovine fetuses from four pregnant cows with neoplasia of the urinary bladder. A papillomaviral evaluation was also performed on the bladder tumors and peripheral blood of these pregnant cows. In all fetal and maternal samples, the genotype distribution of BPVs and OaPVs were evaluated using both their DNA and RNA. A BPV and OaPV coinfection was seen in bladder tumors, whereas only BPV infection was found in peripheral blood. The genotype distribution of both the BPVs and OaPVs detected in placentas and fetal organs indicated a stronger concordance with the viral genotypes detected in bladder tumors rather than in peripheral blood. This suggests that the viruses found in placentas and fetuses may have originated from infected bladders. Our study highlights the likelihood of vertical infections with BPVs and OaPVs and emphasizes the importance of gaining further insights into the mechanisms and consequences of this exposure. This study warrants further research as adverse pregnancy outcomes are a major source of economic losses in cattle breeding.

Evaluation of the Treatment Effects of Conditioned Medium from Human Orbital Adipose-Derived Stem Cells in a Corneal Alkali Burn Rabbit Model

Purpose: This study aimed to evaluate the effects of a new treatment-conditioned medium from human orbital adipose-derived stem cells (OASC-CM)-on corneal recovery after alkali burns in a rabbit model. Methods: The corneal alkali burn rabbit model was established and treated with OASC-CM, conditioned medium from human abdominal subcutaneous adipose-derived stem cells (ABASC-CM), and fresh control culture medium (con-CM) three times a day for 7 days, respectively. Subsequently, the treatment effects were evaluated and compared through clinical, histological, immunohistochemical, and cytokine evaluations. Results: Clinically, OASC-CM alleviated corneal opacity and edema and promoted recovery of corneal epithelium defect. Histologically and immunohistochemically, OASC-CM inhibited neovascularization, conjunctivalization, and immuno-inflammatory reaction, while promoting corneal regeneration and rearrangement. Increased secretion of interleukin-10 and inhibited protein levels of cluster of differentiation 45, interferon-γ, and tumor necrosis factor-α were observed in the alkali-burned cornea after OASC-CM treatment, which might be the relevant molecular mechanism. Conclusions: OASC-CM showed significant effects on the recovery of rabbit corneal alkali burns and eliminated immunological and ethical limitations, representing a new option for corneal wound treatment.

1,25(OH)2D3 improves diabetic wound healing by modulating inflammation and promoting angiogenesis

Vitamin D was found to regulate inflammatory response and angiogenesis, which were often impaired in diabetic wound healing. This study aimed to investigate the effects of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on diabetic wound healing both in vivo and in vitro. Diabetes was induced by high-fat diet combined with streptozotocin. After four weeks of establishing diabetic mouse model, full-thickness excisional wounds were created on their dorsal skin. Then 1,25(OH)2D3 was administered via intraperitoneal injection for 14 consecutive days. Human umbilical vein endothelial cells (HUVECs) were cultured with normal glucose, high glucose, high glucose plus 1,25(OH)2D3. Cell proliferation, migration, tube formation, and expression levels of relevant pathway components were measured. Intervention with 1,25(OH)2D3 significantly increased wound closure rates of diabetic mice. During the inflammatory phase, 1,25(OH)2D3 alleviated excessive inflammation and promoted the transition of macrophages from M1 to M2 phenotype. Regarding vascular endothelial function, 1,25(OH)2D3 significantly up-regulated eNOS protein expression and inhibited Vcam-1 mRNA expression in diabetic mice (P < 0.05). As for angiogenesis, 1,25(OH)2D3 markedly increased CD31-positive area, the protein and mRNA expression of VEGF, VEGFR2, PDGF, and PDGFRβ, as well as the mRNA expression of Bfgf and Egfr (P < 0.05). In vitro, 1,25(OH)2D3 restored impaired cell proliferation, migration, and tube formation induced by high-glucose, and up-regulated expression of angiogenesis-related factors. These protective effects might be mediated through PI3K/AKT/HIF-1α pathway. These findings suggested that 1,25(OH)2D3 accelerated diabetic wound healing by modulating inflammation, restoring vascular endothelial dysfunction, and promoting angiogenesis.

Immune cells in skin inflammation, wound healing, and skin cancer

Given the self-evident importance of cutaneous immunity in the maintenance of body-surface homeostasis, disturbance of the steady-state skin is inextricably intertwined with dysfunction in cutaneous immunity. It is often overlooked by people that skin, well-known as a solid physical barrier, is also a strong immunological barrier, considering the abundant presence of immune cells including lymphocytes, granulocytes, dendritic cells, and macrophages. What's more, humoral immune components including cytokines, immunoglobulins, and antimicrobial peptides are also rich in the skin. This review centers on skin inflammation (acute and chronic, infection and aseptic inflammation), wound healing, and skin cancer to elucidate the elaborate network of immune cells in skin diseases.

Effects of pulsed electrical stimulation on α-smooth muscle actin and type I collagen expression in human dermal fibroblasts

Pulsed electrical stimulation (PES) is known to affect cellular activities. We previously found PES to human dermal fibroblasts (HFs) promoted platelet-derived growth factor subunit A (PDGFA) gene expression, which enhanced proliferation. In this study, we investigated PES effects on fibroblast collagen production and differentiation into myofibroblasts. HFs were electrically stimulated at 4800 Hz and 5 V for 60 min. Imatinib, a specific inhibitor of PDGF receptors, was treated before PES. After 6 h of PES, PDGFA, α-smooth muscle actin (α-SMA), and collagen type I α1 chain gene expressions were upregulated in PES group. Imatinib suppressed the promoted expression except for PDGFA. Immunofluorescence staining and enzyme-linked immunosorbent assay showed the production of α-SMA and collagen I was enhanced in PES group but suppressed in PES + imatinib group at 48 h after PES. Therefore, PES promotes the production of α-SMA and collagen I in fibroblasts, which is triggered by PDGFA that is upregulated early after PES.

The interaction of platelet-related factors with tumor cells promotes tumor metastasis

Platelets not only participate in thrombosis and hemostasis but also interact with tumor cells and protect them from mechanical damage caused by hemodynamic shear stress and natural killer cell lysis, thereby promoting their colonization and metastasis to distant organs. Platelets can affect the tumor microenvironment via interactions between platelet-related factors and tumor cells. Metastasis is a key event in cancer-related death and is associated with platelet-related factors in lung, breast, and colorectal cancers. Although the factors that promote platelet expression vary slightly in terms of their type and mode of action, they all contribute to the overall process. Recognizing the correlation and mechanisms between these factors is crucial for studying the colonization of distant target organs and developing targeted therapies for these three types of tumors. This paper reviews studies on major platelet-related factors closely associated with metastasis in lung, breast, and colorectal cancers.

Association between Platelet-Derived Growth Factor Receptor Alpha Gene Polymorphisms and Platelet-Rich Plasma's Efficiency in Treating Lateral Elbow Tendinopathy-A Prospective Cohort Study

Individual differences in the response to platelet-rich plasma (PRP) therapy can be observed among patients. The genetic background may be the cause of this variability. The current study focused on the impact of genetic variants on the effectiveness of PRP. The aim of the present study was to analyze the impact of single nucleotide polymorphisms (SNP) of the platelet-derived growth factor receptor alpha (PDGFRA) gene on the effectiveness of treating lateral elbow tendinopathy (LET) with PRP. The treatment's efficacy was analyzed over time (2, 4, 8, 12, 24, 52 and 104 weeks after the PRP injection) on 107 patients using patient-reported outcome measures (PROM) and achievement of a minimal clinically important difference (MCID). Four SNPs of the PDGFRA gene (rs7668190, rs6554164, rs869978 and rs1316926) were genotyped using the TaqMan assay method. Patients with the AA genotypes of the rs7668190 and the rs1316926 polymorphisms, as well as carriers of the T allele of rs6554164 showed greater effectiveness of PRP therapy than carriers of other genotypes. Moreover, the studied SNPs influenced the platelets' parameters both in whole blood and in PRP. These results showed that PDGFRA gene polymorphisms affect the effectiveness of PRP treatment. Genotyping the rs6554164 and the rs1316926 SNPs may be considered for use in individualized patient selection for PRP therapy.

Bispecific aptamer-decorated and light-triggered nanoparticles targeting tumor and stromal cells in breast cancer derived organoids: implications for precision phototherapies

BACKGROUND

Based on the established role of cancer-stroma cross-talk in tumor growth, progression and chemoresistance, targeting interactions between tumor cells and their stroma provides new therapeutic approaches. Dual-targeted nanotherapeutics selectively acting on both tumor and stromal cells may overcome the limits of tumor cell-targeting single-ligand nanomedicine due to the complexity of the tumor microenvironment.

METHODS

Gold-core/silica-shell nanoparticles embedding a water-soluble iridium(III) complex as photosensitizer and luminescent probe (Iren-AuSiO2_COOH) were efficiently decorated with amino-terminated EGFR (CL4) and PDGFRβ (Gint4.T) aptamers (Iren-AuSiO2_Aptamer). The targeting specificity, and the synergistic photodynamic and photothermal effects of either single- and dual-aptamer-decorated nanoparticles have been assessed by confocal microscopy and cell viability assays, respectively, on different human cell types including mesenchymal subtype triple-negative breast cancer (MES-TNBC) MDA-MB-231 and BT-549 cell lines (both EGFR and PDGFRβ positive), luminal/HER2-positive breast cancer BT-474 and epidermoid carcinoma A431 cells (only EGFR positive) and adipose-derived mesenchymal stromal/stem cells (MSCs) (only PDGFRβ positive). Cells lacking expression of both receptors were used as negative controls. To take into account the tumor-stroma interplay, fluorescence imaging and cytotoxicity were evaluated in preclinical three-dimensional (3D) stroma-rich breast cancer models.

RESULTS

We show efficient capability of Iren-AuSiO2_Aptamer nanoplatforms to selectively enter into target cells, and kill them, through EGFR and/or PDGFRβ recognition. Importantly, by targeting EGFR+ tumor/PDGFRβ+ stromal cells in the entire tumor bulk, the dual-aptamer-engineered nanoparticles resulted more effective than unconjugated or single-aptamer-conjugated nanoparticles in either 3D spheroids cocultures of tumor cells and MSCs, and in breast cancer organoids derived from pathologically and molecularly well-characterized tumors.

CONCLUSIONS

Our study proposes smart, novel and safe multifunctional nanoplatforms simultaneously addressing cancer-stroma within the tumor microenvironment, which are: (i) actively delivered to the targeted cells through highly specific aptamers; (ii) localized by means of their luminescence, and (iii) activated via minimally invasive light, launching efficient tumor death, thus providing innovative precision therapeutics. Given the unique features, the proposed dual targeted nanoformulations may open a new door to precision cancer treatment.

Multi-omics analysis revealed the regulation mode of intratumor microorganisms and microbial signatures in gastrointestinal cancer

OBJECTIVE

Gastrointestinal cancer is one of the most common malignant tumors in the world, and its incidence rate is always high. In recent years, research has shown that microorganisms may play a broad role in the diagnosis, pathogenesis, and treatment of cancer.

METHODS

In this study, samples were first classified according to the microbial expression data of Gastrointestinal cancer, followed by functional enrichment and Immunoassay. In order to better understand the role of intratumor microorganisms in the prognosis, we screened gene signatures and constructed risk model through univariate cox and lasso regression and multivariable cox, then screened microbial signatures using zero-inflated model regression model and constructed risk index (RI), and finally predicted the immunotherapeutic effect of the risk model.

RESULTS

The results indicate that the composition of tumor microorganisms in the C3 subtype is closely related to tumor angiogenesis, and there is a significant difference in the proportion of innate and acquired immune cells between the C2 and C1 subtypes, as well as differences in the physiological functions of immune cells. There are significant differences in the expression of microbial signatures between high and low risk subtypes, with 9 microbial signatures upregulated in high risk subtypes and 15 microbial signatures upregulated in low risk subtypes. These microbial signatures were significantly correlated with the prognosis of patients. The results of immunotherapy indicate that immunotherapy for high-risk subtypes is more effective.

CONCLUSION

Overall, we analyze from the perspective of microorganisms within tumors, pointing out new directions for the diagnosis and treatment of cancer.

Ascites does not accompany pleural effusion developing under dasatinib therapy in patients with CML-CP

Objectives

Pleural effusion (PE) is the most frequent pulmonary complication of dasatinib, a tyrosine kinase inhibitor (TKI). Concurrent pericardial effusions have been reported in about one-third of the cases. In this study, we aimed to investigate ascites generation in chronic-phase chronic myeloid leukemia (CML-CP) patients developing PE under dasatinib.

Methods

We conducted a cross-sectional study to evaluate whether pericardial effusion and ascites accompany PE in CML-CP patients treated with dasatinib. For this purpose, consecutive patients with CML-CP who developed PE under dasatinib therapy have been evaluated with chest X-ray, transthoracic echocardiography, and abdominal ultrasonography.

Results

There were seven patients, and the median age was 50 years (range, 31-73 years). Most of patients were male (n=5). All patients received imatinib as first-line TKI. Six patients received dasatinib following imatinib failure in second line. The median duration from dasatinib initiation to PE generation was 58 months (range, 8-135 months). Consequently, four patients had grade 1 pericardial effusion, and no patient had ascites.

Conclusions

In our small study, dasatinib-related PE was associated with low-grade pericardial effusion but no ascites. There are hypothetical explanations of this phenomenon including the simultaneous activation/inhibition of kinases; however, more research needs to be performed on this topic.

Reversing immunosuppression in the tumor microenvironment of fibrolamellar carcinoma via PD-1 and IL-10 blockade

Fibrolamellar carcinoma (FLC) is a rare liver tumor driven by the DNAJ-PKAc fusion protein that affects healthy young patients. Little is known about the immune response to FLC, limiting rational design of immunotherapy. Multiplex immunohistochemistry and gene expression profiling were performed to characterize the FLC tumor immune microenvironment and adjacent non-tumor liver (NTL). Flow cytometry and T cell receptor (TCR) sequencing were performed to determine the phenotype of tumor-infiltrating immune cells and the extent of T cell clonal expansion. Fresh human FLC tumor slice cultures (TSCs) were treated with antibodies blocking programmed cell death protein-1 (PD-1) and interleukin-10 (IL-10), with results measured by cleaved caspase-3 immunohistochemistry. Immune cells were concentrated in fibrous stromal bands, rather than in the carcinoma cell compartment. In FLC, T cells demonstrated decreased activation and regulatory T cells in FLC had more frequent expression of PD-1 and CTLA-4 than in NTL. Furthermore, T cells had relatively low levels of clonal expansion despite high TCR conservation across individuals. Combination PD-1 and IL-10 blockade signficantly increased cell death in human FLC TSCs. Immunosuppresion in the FLC tumor microenvironment is characterized by T cell exclusion and exhaustion, which may be reversible with combination immunotherapy.

Anti-angiogenesis in colorectal cancer therapy

The morbidity of colorectal cancer (CRC) has risen to third place among malignant tumors worldwide. In addition, CRC is a common cancer in China whose incidence increases annually. Angiogenesis plays an important role in the development of tumors because it can bring the nutrients that cancer cells need and take away metabolic waste. Various mechanisms are involved in the formation of neovascularization, and vascular endothelial growth factor is a key mediator. Meanwhile, angiogenesis inhibitors and drug resistance (DR) are challenges to consider when formulating treatment strategies for patients with different conditions. Thus, this review will discuss the molecules, signaling pathways, microenvironment, treatment, and DR of angiogenesis in CRC.

Crosstalk among podocytes, glomerular endothelial cells and mesangial cells in diabetic kidney disease: an updated review

Diabetic kidney disease (DKD) is a long-term and serious complication of diabetes that affects millions of people worldwide. It is characterized by proteinuria, glomerular damage, and renal fibrosis, leading to end-stage renal disease, and the pathogenesis is complex and involves multiple cellular and molecular mechanisms. Among three kinds of intraglomerular cells including podocytes, glomerular endothelial cells (GECs) and mesangial cells (MCs), the alterations in one cell type can produce changes in the others. The cell-to-cell crosstalk plays a crucial role in maintaining the glomerular filtration barrier (GFB) and homeostasis. In this review, we summarized the recent advances in understanding the pathological changes and interactions of these three types of cells in DKD and then focused on the signaling pathways and factors that mediate the crosstalk, such as angiopoietins, vascular endothelial growth factors, transforming growth factor-β, Krüppel-like factors, retinoic acid receptor response protein 1 and exosomes, etc. Furthermore, we also simply introduce the application of the latest technologies in studying cell interactions within glomerular cells and new promising mediators for cell crosstalk in DKD. In conclusion, this review provides a comprehensive and updated overview of the glomerular crosstalk in DKD and highlights its importance for the development of novel intervention approaches.

Gliomas: a reflection of temporal gliogenic principles

The hijacking of early developmental programs is a canonical feature of gliomas where neoplastic cells resemble neurodevelopmental lineages and possess mechanisms of stem cell resilience. Given these parallels, uncovering how and when in developmental time gliomagenesis intersects with normal trajectories can greatly inform our understanding of tumor biology. Here, we review how elapsing time impacts the developmental principles of astrocyte (AS) and oligodendrocyte (OL) lineages, and how these same temporal programs are replicated, distorted, or circumvented in pathological settings such as gliomas. Additionally, we discuss how normal gliogenic processes can inform our understanding of the temporal progression of gliomagenesis, including when in developmental time gliomas originate, thrive, and can be pushed towards upon therapeutic coercion.

Review of treatment strategies after lymphadenectomy: from molecular therapeutics to immediate microsurgical lymphatic reconstruction

OBJECTIVE

Lymphedema is a common complication of cancer treatment, such as lymphadenectomy and radiation therapy. It is a debilitating condition with pathologic tissue changes that hinder effective curative treatment and jeopardize patients' quality of life. Various attempts to prevent the development of lymphedema have been made, with improvements in the incidence of the pathology. However, it is still prevalent among survivors of cancer. In this paper, we review both molecular therapeutics and immediate surgical lymphatic reconstruction as treatment strategies after lymphadenectomy. Specifically, we discuss pro-lymphangiogenic molecules that have proved efficient in animal models of lymphedema and clinical trials, and review currently available microsurgical techniques of immediate lymphatic reconstruction.

METHODS

A literature search was conducted in PubMed, Embase, Cochrane Library, and Google Scholar through May 2022. Searches were done separately for molecular therapeutics and microsurgical techniques for immediate lymphatic reconstruction. Search terms used for (1) non-surgical methods include 'lymphangiogenesis,' 'lymphedema,' 'growth factor,' and 'gene therapy.' Search terms used for (2) surgical methods include 'lymphedema,' 'lymph node excision,' 'lymphatic vessels,' 'primary prevention,' and 'microsurgery.'

RESULTS

Various pro-lymphangiogenic factors with therapeutic potential include VEGF-C, VEGF-D, HGF, bFGF, PDGF, IGF, Retinoic acid, Ang-1, S1P, TLR4, and IL-8. Microsurgical lymphatic reconstruction for prevention of secondary lymphedema includes lymphovenous anastomosis, vascularized lymph node flap transfer, and lymph-interpositional flap transfer, with promising clinical outcomes.

CONCLUSIONS

With growing knowledge of the lymphangiogenic pathway and lymphedema pathology and advances in microsurgical techniques to restore lymphatic channels, molecular and surgical approaches may represent a promising method for primary prevention of lymphedema.

Evaluation of the effect of injectable platelet-rich fibrin (i-PRF) in wound healing and growth factor release in rats: a split-mouth study

This experimental study aimed to evaluate the effects of injectable platelet-rich fibrin (i-PRF) on mucosal healing and the release of growth factors in rats. 40 rats were used; i-PRF was administered in the right buccal area while saline was injected in the left. Cytokeratin, FGF, PDGF, TGF, and VEGF expressions were determined with immunohistochemistry. Gene expressions of EGF, TGF-β, and VEGF were analysed. Epithelialization started on the 3rd day, and connective tissue maturation was more prominent in the i-PRF-applied group. Also, the releases of VEGF, EGF, TGF-β, PDGF, and FGF were higher in the i-PRF group during the 14 days. Gene expression analysis showed that changes in TGF-β at 14 days after i-PRF injection and VEGF after 21 days were statistically significant. The results of this study suggested that autologous i-PRF application enhanced the healing of oral mucosal wounds by increasing the release of growth factors for 21 days.

Extra Virgin Olive Oil Phenolic Compounds Modulate the Gene Expression of Biomarkers Involved in Fibroblast Proliferation and Differentiation

Extra virgin olive oil phenolic compounds have been identified as possible biostimulant agents against different pathological processes, including alterations in healing processes. However, there is little evidence on the molecular mechanisms involved in this process. The aim was to analyse the effect of hydroxytyrosol, tyrosol, and oleocanthal on fibroblast gene expression. PCR was used to determine the expression of different differentiation markers, extracellular matrix elements, and growth factors in cultured human fibroblasts CCD-1064Sk treated with different doses of hydroxytyrosol (10-5 M and 10-6 M), tyrosol (10-5 M and 10-6 M), and oleocanthal (10-6 M and 10-7 M). After 24 h of hydroxytyrosol treatment, increased expression of connective tissue growth factor, fibroblast growth factor (FGF), platelet-derived growth factor, vascular endothelial growth factor, transforming growth factor β1 (TGF-β1), and their receptors was observed. Tyrosol and olecanthal modulated the expression of FGF and TGFβR1. All phytochemicals tested modified the expression of differentiation markers and extracellular matrix elements, increasing gene expression of actin, fibronectin, decorin, collagen I, and III. Phenolic compounds present in extra virgin olive could have a beneficial effect on tissue regeneration by modulating fibroblast physiology.

Antifibrotic Drugs against Idiopathic Pulmonary Fibrosis and Pulmonary Fibrosis Induced by COVID-19: Therapeutic Approaches and Potential Diagnostic Biomarkers

The COVID-19 pandemic has had a significant impact on the health and economy of the global population. Even after recovery from the disease, post-COVID-19 symptoms, such as pulmonary fibrosis, continue to be a concern. This narrative review aims to address pulmonary fibrosis (PF) from various perspectives, including the fibrotic mechanisms involved in idiopathic and COVID-19-induced pulmonary fibrosis. On the other hand, we also discuss the current therapeutic drugs in use, as well as those undergoing clinical or preclinical evaluation. Additionally, this article will address various biomarkers with usefulness for PF prediction, diagnosis, treatment, prognosis, and severity assessment in order to provide better treatment strategies for patients with this disease.

Co-expression patterns of cancer associated fibroblast markers reveal distinct subgroups related to patient survival in oropharyngeal squamous cell carcinoma

Background: The incidence of oropharyngeal squamous cell carcinoma (OPSCC) is rapidly increasing in high income countries due to its association with persistent high-risk human papilloma virus (HPV) infection. Recent scientific advances have highlighted the importance of the tumor microenvironment in OPSCC. In this study, including 216 OPSCC patients, we analyze the composition of four established markers of cancer associated fibroblasts (CAFs) in the context of intratumoral CD8 T-cell infiltration. Methods: Immunohistochemical staining for fibroblast activation protein (FAP), platelet-derived growth factor receptor beta (PDGFRb), periostin, alpha smooth muscle actin (α-SMA) and CD8 were analyzed digitally and their association with survival, tumor- and patient characteristics was assessed. Results: Co-expression of CAF markers was frequent but not associated with HPV status. FAPhigh and PDGFRbhigh expression were associated with increased CD8 T-cell infiltration. Low expression of PDGFRb improved patient survival in female patients but not in male patients. We identified PDGFRblow periostinlow α-SMAlow status as an independent predictor of improved survival (hazard ratio 0.377, p = 0.006). Conclusion: These findings elucidate the co-expression of four established CAF markers in OPSCC and underscore their association with T-cell infiltration and patient survival. Future analyses of CAF subgroups in OPSCC may enable the development of individualized therapies.

Biological processes and factors involved in soft and hard tissue healing

Wound healing is a complex and iterative process involving myriad cellular and biologic processes that are highly regulated to allow satisfactory repair and regeneration of damaged tissues. This review is intended to be an introductory chapter in a volume focusing on the use of platelet concentrates for tissue regeneration. In order to fully appreciate the clinical utility of these preparations, a sound understanding of the processes and factors involved in soft and hard tissue healing. This encompasses an appreciation of the cellular and biological mediators of both soft and hard tissues in general as well as specific consideration of the periodontal tissues. In light of good advances in this basic knowledge, there have been improvements in clinical strategies and therapeutic management of wound repair and regeneration. The use of platelet concentrates for tissue regeneration offers one such strategy and is based on the principles of cellular and biologic principles of wound repair discussed in this review.

Platelet-derived growth factor receptor beta is required for embryonic specification and confinement of the adult white adipose lineage

White adipose tissue (WAT) development and adult homeostasis rely on distinct adipocyte progenitor cells (APCs). While adult APCs are defined early during embryogenesis and generate adipocytes after WAT organogenesis, the mechanisms underlying adult adipose lineage determination and preservation remain undefined. Here, we uncover a critical role for platelet-derived growth factor receptor beta (Pdgfrβ) in identifying the adult APC lineage. Without Pdgfrβ, APCs lose their adipogenic competency to incite fibrotic tissue replacement and inflammation. Through lineage tracing analysis, we reveal that the adult APC lineage is lost and develops into macrophages when Pdgfrβ is deleted embryonically. Moreover, to maintain the APC lineage, Pdgfrβ activation stimulates p38/MAPK phosphorylation to promote APC proliferation and maintains the APC state by phosphorylating peroxisome proliferator activated receptor gamma (Pparγ) at serine 112. Together, our findings identify a role for Pdgfrβ acting as a rheostat for adult adipose lineage confinement to prevent unintended lineage switches.

Functional characterization of the dimeric form of PDGF-derived fusion peptide fabricated based on theoretical arguments

A skin wound leads to the loss of skin integrity and the influx of pathogens into the tissue. Platelet-derived growth factors (PDGFs) are cytokines released from alpha granules during wound healing and interact with their cell surface receptors and activate signals involved in chemotaxis, growth, proliferation, and differentiation pathways. Due to the low stability of growth factors (GFs), a new peptide-derived PDGF-BB was designed, expressed in the Shuffle strain of E. coli, and purified by Ni-NTA agarose affinity column chromatography. The effect of fusion peptide was then evaluated on L929 fibroblast cells and animal models with skin lesions. In vitro, studies showed that the peptide led to an increase in the migration of fibroblast cells in the scratch assay. Its positive effect on wound healing was also observed in the skin-injured rats after 3, 7, and 12 days. A significant rise in neutrophils and granular tissue formation, re-epithelialization, angiogenesis, and collagen formation was exhibited on the third day of treatment when compared to the control group. The results showed that, despite reducing PDGF size, the fusion peptide was able to maintain at least some of the known functions attributed to full-length PDGF and showed positive results in wound healing.

The underlying mechanisms of DNA methylation in high salt memory in hypertensive vascular disease

This study demonstrates the effect and DNA methylation-related mechanisms of a high-salt diet and salt memory-induced hypertension and vasculopathy. Thirty Sprague Dawley rats were randomly divided into a control (CON) group (n = 6) and a modeling group (n = 24). A 12% NaCl solution (1 mL/100 g) was intragastrically administered for 60 consecutive days for modeling. An increase in blood pressure up to 140 mmHg was considered successful modeling. Twelve of fifteen successfully modeled rats were randomly selected and divided into a High Salt Diet (HSD) group and a High Salt Memory (HSM) group (n = 6). Rats in HSD group were intragastrically administered a 12% NaCl solution, while rats in HSM group were administered a 3% NaCl solution twice a day for 30 days. At the end of the intervention, blood pressure and the serum levels of ET-1, NO, TNF-α and IL-1β were measured. RRBS-heavy sulfite sequencing technology was selected for DNA methylation analysis. The systolic blood pressure of rats in the HSD group and HSM group was significantly higher than that in the CON group. Compared with those in the CON group, the serum levels of ET-1 in the HSM group and the serum levels of NO in the HSD group and HSM group were significantly increased. The methylation level of the CON group was lower than that of the HSD group and the HSM group, and there was no significant difference between the HSD group and the HSM group. The methylation level of Myoz3 was downregulated in the HSD group and HSM group. The methylation level of Fgd3 were upregulated in HSD group and downregulated in the HSM group. The methylation levels of AC095693.1, Adamts3, PDGFA and PDGFRα were downregulated in the HSD group and upregulated in the HSM group. According to the GO database, the differentially methylated genes were significantly enriched in the coordination of cell function, genetic development, and RNA transcription. There were three main metabolic pathways that were enriched in the differentially expressed genes between the groups: the PI3K-Akt signaling pathway, MAPK signaling pathway, and Hippo signaling pathway. Excessive salt intake may cause hypertension and vascular damage, and this damage may continue after the reduction of salt intake. Therefore, salt memory phenomenon exists, and this memory effect may be correlated with the levels of DNA methylation.

Antifibrotic effects of sodium-glucose cotransporter-2 inhibitors: A comprehensive review

BACKGROUND AND AIMS

Scar tissue accumulation in organs is the underlying cause of many fibrotic diseases. Due to the extensive array of organs affected, the long-term nature of fibrotic processes and the large number of people who suffer from the negative impact of these diseases, they constitute a serious health problem for modern medicine and a huge economic burden on society. Sodium-glucose cotransporter-2 inhibitors (SGLT2is) are a relatively new class of anti-diabetic pharmaceuticals that offer additional benefits over and above their glucose-lowering properties; these medications modulate a variety of diseases, including fibrosis. Herein, we have collated and analyzed all available research on SGLT2is and their effects on organ fibrosis, together with providing a proposed explanation as to the underlying mechanisms.

METHODS

PubMed, ScienceDirect, Google Scholar and Scopus were searched spanning the period from 2012 until April 2023 to find relevant articles describing the antifibrotic effects of SGLT2is.

RESULTS

The majority of reports have shown that SGLT2is are protective against lung, liver, heart and kidney fibrosis as well as arterial stiffness. According to the results of clinical trials and animal studies, many SGLT2 inhibitors are promising candidates for the treatment of fibrosis. Recent studies have demonstrated that SGLT2is affect an array of cellular processes, including hypoxia, inflammation, oxidative stress, the renin-angiotensin system and metabolic activities, all of which have been linked to fibrosis.

CONCLUSION

Extensive evidence indicates that SGLT2is are promising treatments for fibrosis, demonstrating protective effects in various organs and influencing key cellular processes linked to fibrosis.

Clinical Observation of Various Types of Idiopathic Hypertrophic Cranial Pachymeningitis

BACKGROUND

To assist doctors in making better treatment decisions and improve patient prognosis, it is important to determine which therapy modalities are suitable for various forms of idiopathic hypertrophic cranial pachymeningitis (IHCP).

METHODS

All cases were received from the hospital medical record system, and some follow-up information was gathered through telephone follow-up.

RESULTS

A total of 26 patients, 14 men and 12 women, with ages ranging from 20 to 73 years and a mean of 47.42 years, were included in the research. Regular types were less likely to recur than irregular and nodular types, focal types were less likely to recur than diffuse types, and corticosteroid-refractory types were more likely to recur than corticosteroid-sensitive types.

CONCLUSIONS

The extent and shape of the lesion and susceptibility to corticosteroids are potential factors that could influence recurrence. Futhermore, this paper also proposes the fibroblasts as a new therapeutic target which may improve the quality of prognostic survival of patients.

Plasma cytokine and growth factor response to acute psychosocial stress in major depressive disorder

BACKGROUND

Pro-inflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor (TNF)-α are elevated in response to psychosocial stress; however, less is known about other inflammatory markers.

METHODS

We explored response to the Trier Social Stress Test (TSST) of 16 cytokines and growth factors in patients with major depressive disorder (MDD, n = 12) vs. healthy volunteers (HV, n = 16). Outcomes were baseline and post-stress levels estimated by area under the curve (AUCi) and peak change over 3 timepoints. We also explored correlations between biomarkers and clinical characteristics.

RESULTS

Baseline concentrations were higher in MDD for platelet-derived growth factor (PDGF)-AB/BB (p = 0.037, d = 0.70), granulocyte-macrophage colony-stimulating factor (GM-CSF, p = 0.033, d = 0.52), and IL-8 (p = 0.046, d = 0.74). After TSST, AUCi was higher in MDD for GM-CSF (p = 0.003, d = 1.21), IL-5 (p = 0.014, d = 1.62), and IL-27 (p = 0.041, d = 0.74). In MDD, depression severity correlated positively with soluble CD40L (sCD40L) for AUCi (Spearman's ρ = 0.76, p = 0.004) and with baseline vascular endothelial growth factor A (VEGFA, r = 0.85, p < 0.001), but negatively with baseline monokine induced by gamma interferon (MIG, aka CXCL9; r = -0.77, p = 0.003).

CONCLUSIONS

Effect sizes were robust in this exploratory study, although interpretation of the results must be cautious, given small sample size and multiple comparisons. Differential study of stress-induced biomarkers may have important ramifications for MDD treatment.

The uterine secretory cycle: recurring physiology of endometrial outputs that setup the uterine luminal microenvironment

Conserved in female reproduction across all mammalian species is the estrous cycle and its regulation by the hypothalamic-pituitary-gonadal (HPG) axis, a collective of intersected hormonal events that are crucial for ensuring uterine fertility. Nonetheless, knowledge of the direct mediators that synchronously shape the uterine microenvironment for successive yet distinct events, such as the transit of sperm and support for progressive stages of preimplantation embryo development, remain principally deficient. Toward understanding the timed endometrial outputs that permit luminal events as directed by the estrous cycle, we used Bovidae as a model system to uniquely surface sample and study temporal shifts to in vivo endometrial transcripts that encode for proteins destined to be secreted. The results revealed the full quantitative profile of endometrial components that shape the uterine luminal microenvironment at distinct phases of the estrous cycle (estrus, metestrus, diestrus, and proestrus). In interpreting this comprehensive log of stage-specific endometrial secretions, we define the "uterine secretory cycle" and extract a predictive understanding of recurring physiological actions regulated within the uterine lumen in anticipation of sperm and preimplantation embryonic stages. This repetitive microenvironmental preparedness to sequentially provide operative support was a stable intrinsic framework, with only limited responses to sperm or embryos if encountered in the lumen within the cyclic time period. In uncovering the secretory cycle and unraveling realistic biological processes, we present novel foundational knowledge of terminal effectors controlled by the HPG axis to direct a recurring sequence of vital functions within the uterine lumen.NEW & NOTEWORTHY This study unravels the recurring sequence of changes within the uterus that supports vital functions (sperm transit and development of preimplantation embryonic stages) during the reproductive cycle in female Ruminantia. These data present new systems knowledge in uterine reproductive physiology crucial for setting up in vitro biomimicry and artificial environments for assisted reproduction technologies for a range of mammalian species.

Systems genetics and bioinformatics analyses using ESR1-correlated genes identify potential candidates underlying female bone development

Estrogen receptor α (ESR1) is involved in E2 signaling and plays a major role in postmenopausal bone loss. However, the molecular network underlying ESR1 has not been explored. We used systems genetics and bioinformatics to identify important genes associated with Esr1 in postmenopausal bone loss. We identified ~2300 Esr1-coexpressed genes in female BXD bone femur, functional analysis of which revealed 'osteoblast signaling' as the most enriched pathway. PPI network led to the identification of 25 'female bone candidates'. The gene-regulatory analysis revealed RUNX2 as a key TF. ANKRD1 and RUNX2 were significantly different between osteoporosis patients and healthy controls. Sp7, Col1a1 and Pth1r correlated with multiple femur bone phenotypes in BXD mice. miR-3121-3p targeted Csf1, Ankrd1, Sp7 and Runx2. β-estradiol treatment markedly increased the expression of these candidates in mouse osteoblast. Our study revealed that Esr1-correlated genes Ankrd1, Runx2, Csf1 and Sp7 may play important roles in female bone development.

PDGFRα/β heterodimer activation negatively affects downstream ERK1/2 signaling and cellular proliferation

The platelet-derived growth factor receptor (PDGFR) family of receptor tyrosine kinases allows cells to communicate with one another by binding to growth factors at the plasma membrane and activating intracellular signaling pathways to elicit responses such as migration, proliferation, survival and differentiation. The PDGFR family consists of two receptors, PDGFRα and PDGFRβ, that dimerize to form PDGFRα homodimers, PDGFRα/β heterodimers and PDGFRβ homodimers. Here, we overcame prior technical limitations in visualizing and purifying PDGFRα/β heterodimers by generating a cell line stably expressing C-terminal fusions of PDGFRα and PDGFRβ with bimolecular fluorescence complementation fragments corresponding to the N-terminal and C-terminal regions of the Venus fluorescent protein, respectively. We found that these receptors heterodimerize relatively quickly in response to PDGF-BB ligand treatment, with a peak of receptor autophosphorylation following 5 minutes of ligand stimulation. Moreover, we demonstrated that PDGFRα/β heterodimers are rapidly internalized into early endosomes, particularly signaling endosomes, where they dwell for extended lengths of time. We showed that PDGFRα/β heterodimer activation does not induce downstream phosphorylation of ERK1/2 and significantly inhibits cell proliferation. Further, we characterized the PDGFR dimer-specific interactome and identified MYO1D as a novel protein that preferentially binds PDGFRα/β heterodimers. We demonstrated that knockdown of MYO1D leads to retention of PDGFRα/β heterodimers at the plasma membrane, resulting in increased phosphorylation of ERK1/2 and increased cell proliferation. Collectively, our findings impart valuable insight into the molecular mechanisms by which specificity is introduced downstream of PDGFR activation to differentially propagate signaling and generate distinct cellular responses.

Ubiquinol attenuates γ-radiation induced coronary and aortic changes via PDGF/p38 MAPK/ICAM-1 related pathway

Endothelial vascular injury is one of the most pivotal disorders emerging during radiotherapy. It is crucial to rely on strong antioxidants to defend against vascular damage. The current study was carried out to investigate the ameliorative effect of ubiquinol (Ubq) against gamma (γ)-radiation induced aortic and coronary changes, with highlighting its role in suppression of p38 mitogen activated protein kinase (MAPK). Exposure to γ-radiation was adopted as a potent detrimental model that induces vascular tissue damage. Concisely, male albino rats were irradiated at a dose level of 7 Gy and treated daily with Ubq (10 mg/kg/day, p.o.) for 7 days pre-and post-irradiation. At the end of the experiment, lipid profile, 8-hydroxydeoxyguanosine (8-OHdG), gene expression of intercellular adhesion molecule (ICAM-1), platelet derived growth factor (PDGF), p38 MAPK and matrix metalloproteinase-9 (MMP-9) were estimated. Exposure to radiation significantly deteriorates aortic and coronary tissues. Conversely, administration of Ubq significantly reduced serum t-cholesterol, LDL and triglycerides (p = 0.001). In addition, Ubq prevented oxidative DNA damage (8-OHdG) (p = 0.1) and reduced serum MMP-9 (p = 0.001) which contributed to the endothelial cells damage. The positive impact of Ubq was more apparent in suppression of both PDGF (p = 0.001) and p38 MAPK (p = 0.1) protein concentrations, leading subsequently in reduction of ICAM-1 (p = 0.001) gene expression. As a conclusion, vascular endothelial damage brought on by γ-radiation is one of the leading causes of coronary and aortic deteriorations which could be successfully mitigated by Ubq.

Generation and characterization of PDGFRα-GFP knock-in mice for visualization of PDGFRα+ fibroblasts in vivo

The platelet-derived growth factor (PDGF) and its receptor, PDGFRα, are critical for tissue development and injury repair. To track PDGFRα-expressing cells in vivo, we generated a knock-in mouse line that expresses green fluorescent protein (GFP) under the control of the PDGFRα promoter. This genetic tool enabled us to detect PDGFRα expression in various organs during both neonatal and adult stages. Additionally, we confirmed the correlation between endogenous PDGFRα and transgenic PDGFRα expression using mouse injury models, showing the potential of this genetic reporter for studying PDGFRα-mediated signaling pathways and developing therapeutic strategies. Overall, the PDGFRα-GFP knock-in mouse line serves as a valuable tool for investigating the biology of PDGFRα and its role in normal development and disease.

Impact of a High-Fat Diet at a Young Age on Wound Healing in Mice

As the prevalence of juvenile-onset obesity rises globally, the multitude of related health consequences gain significant importance. In this context, obesity is associated with impaired cutaneous wound healing. In experimental settings, mice are the most frequently used model for investigating the effect of high-fat diet (HFD) chow on wound healing in wild-type or genetically manipulated animals, e.g., diabetic ob/ob and db/db mice. However, these studies have mainly been performed on adult animals. Thus, in the present study, we introduced a mouse model for a juvenile onset of obesity. We exposed 4-week-old mice to an investigational feeding period of 9 weeks with an HFD compared to a regular diet (RD). At a mouse age of 13 weeks, we performed excisional and incisional wounding and measured the healing rate. Wound healing was examined by serial photographs with daily wound size measurements of the excisional wounds. Histology from incisional wounds was performed to quantify granulation tissue (thickness, quality) and angiogenesis (number of blood vessels per mm2). The expression of extracellular matrix proteins (collagen types I/III/IV, fibronectin 1, elastin), inflammatory cytokines (MIF, MIF-2, IL-6, TNF-α), myofibroblast differentiation (α-SMA) and macrophage polarization (CD11c, CD301b) in the incisional wounds were evaluated by RT-qPCR and by immunohistochemistry. There was a marked delay of wound closure in the HFD group with a decrease in granulation tissue quality and thickness. Additionally, inflammatory cytokines (MIF, IL-6, TNF-α) were significantly up-regulated in HFD- when compared to RD-fed mice measured at day 3. By contrast, MIF-2 and blood vessel expression were significantly reduced in the HFD animals, starting at day 1. No significant changes were observed in macrophage polarization, collagen expression, and levels of TGF-β1 and PDGF-A. Our findings support that an early exposition to HFD resulted in juvenile obesity in mice with impaired wound repair mechanisms, which may be used as a murine model for obesity-related studies in the future.

Bone-derived PDGF-BB drives brain vascular calcification in male mice

Brain vascular calcification is a prevalent age-related condition often accompanying neurodegenerative and neuroinflammatory diseases. The pathogenesis of large-vessel calcifications in peripheral tissue is well studied, but microvascular calcification in the brain remains poorly understood. Here, we report that elevated platelet-derived growth factor BB (PDGF-BB) from bone preosteoclasts contributed to cerebrovascular calcification in male mice. Aged male mice had higher serum PDGF-BB levels and a higher incidence of brain calcification compared with young mice, mainly in the thalamus. Transgenic mice with preosteoclast-specific Pdgfb overexpression exhibited elevated serum PDGF-BB levels and recapitulated age-associated thalamic calcification. Conversely, mice with preosteoclast-specific Pdgfb deletion displayed diminished age-associated thalamic calcification. In an ex vivo cerebral microvascular culture system, PDGF-BB dose-dependently promoted vascular calcification. Analysis of osteogenic gene array and single-cell RNA-Seq (scRNA-Seq) revealed that PDGF-BB upregulated multiple osteogenic differentiation genes and the phosphate transporter Slc20a1 in cerebral microvessels. Mechanistically, PDGF-BB stimulated the phosphorylation of its receptor PDGFRβ (p-PDGFRβ) and ERK (p-ERK), leading to the activation of RUNX2. This activation, in turn, induced the transcription of osteoblast differentiation genes in PCs and upregulated Slc20a1 in astrocytes. Thus, bone-derived PDGF-BB induced brain vascular calcification by activating the p-PDGFRβ/p-ERK/RUNX2 signaling cascade in cerebrovascular cells.

A high-throughput single-cell RNA expression profiling method identifies human pericyte markers

AIMS

We sought to identify and optimise a universally available histological marker for pericytes in the human brain. Such a marker could be a useful tool for researchers. Further, identifying a gene expressed relatively specifically in human pericytes could provide new insights into the biological functions of this fascinating cell type.

METHODS

We analysed single-cell RNA expression profiles derived from different human and mouse brain regions using a high-throughput and low-cost single-cell transcriptome sequencing method called EasySci. Through this analysis, we were able to identify specific gene markers for pericytes, some of which had not been previously characterised. We then used commercially (and therefore universally) available antibodies to immunolabel the pericyte-specific gene products in formalin-fixed paraffin-embedded (FFPE) human brains and also performed immunoblots to determine whether appropriately sized proteins were recognised.

RESULTS

In the EasySci data sets, highly pericyte-enriched expression was notable for SLC6A12 and SLC19A1. Antibodies against these proteins recognised bands of approximately the correct size in immunoblots of human brain extracts. Following optimisation of the immunohistochemical technique, staining for both antibodies was strongly positive in small blood vessels and was far more effective than a PDGFRB antibody at staining pericyte-like cells in FFPE human brain sections. In an exploratory sample of other human organs (kidney, lung, liver, muscle), immunohistochemistry did not show the same pericyte-like pattern of staining.

CONCLUSIONS

The SLC6A12 antibody was well suited for labelling pericytes in human FFPE brain sections, based on the combined results of single-cell RNA-seq analyses, immunoblots and immunohistochemical studies.

Tyrosine kinase inhibitors in osteosarcoma: Adapting treatment strategiesa

Osteosarcoma (OS) is an aggressive primary bone malignancy that metastasizes rapidly. The standard of care has changed little over the previous four decades, and survival rates have plateaued. In this context, tyrosine kinase inhibitors (TKIs) emerge as potential treatments. A literature search was conducted to collect data related to receptor tyrosine kinase genetic alterations and expression in OS specimens. Gene amplification and protein expression of these receptors were linked to prognosis and tumor behavior. Relevant TKIs were evaluated as monotherapies and as parts of combination therapies. Certain TKIs, such as apatinib, regorafenib, and cabozantinib, present a potential therapeutic avenue for OS patients, especially when combined with chemotherapy. Producing long-lasting responses and enhancing quality of life remain key goals in OS treatment. To this effect, optimizing the use of TKIs by identifying biomarkers predictive of response and assessing promising TKIs in larger-scale trials to validate the efficacy and safety outcomes relative to these drugs reported in phase II clinical trials. To this effect, it is necessary to identify biomarkers predictive of response to TKIs in larger-scale trials and to validate the efficacy and safety of these drugs reported in phase II clinical trials.

Myeloid Cell-Specific Deletion of PDGFR-α Promotes Dysbiotic Intestinal Microbiota and thus Increased Colitis Susceptibility

BACKGROUND AND AIMS

The incidence of inflammatory bowel diseases [IBD] is steadily increasing, and thus the identification of new targets to improve therapy is a major goal. Growth factors of the PDGF family and their receptors are expressed early in intestinal development and are found in mononuclear cells and macrophages in adult tissues. Macrophages play a distinct role in the pathogenesis of IBD since their function is crucial to maintaining tolerance.

METHODS

We aimed to study the role of myeloid expression of PDGFR-α in mediating intestinal homeostasis in mouse IBD and infectious models.

RESULTS

Our results show that loss of myeloid PDGFR-α increases susceptibility to dextran saline sulphate-induced colitis. Accordingly, LysM-PDGFR-α-/- mice showed higher colitis scores, and reduced levels of anti-inflammatory macrophages compared to control mice. This effect was mediated via a pro-colitogenic microbiota, which developed in the absence of myeloid PDGFR-α and caused increased colitis susceptibility in gnotobiotic mice upon faecal microbiota transplantation compared to controls. Furthermore, LysM-PDGFR-α-/- mice had a leaky gut, accompanied by impaired phagocytosis, resulting in a severe barrier defect.

CONCLUSIONS

Taken together, our results indicate a protective role for myeloid PDGFR-α in maintaining gut homeostasis by promoting a protective intestinal microbiota and providing an anti-inflammatory macrophage phenotype.

Molecular mechanisms of uterine incision healing and scar formation

Wound healing is a tandem process involving inflammation, proliferation, and remodeling, through which damage is repaired and ultimately scar tissue is formed. This process mainly relies on the complex and extensive interaction of growth factors and cytokines, which coordinate the synthesis of various cell types. The loss of normal regulation in any part of this process can lead to excessive scarring or unhealed wounds. Recent studies have shown that it is possible to improve wound healing and even achieve scar-free wound healing through proper regulation of cytokines and molecules in this process. In recent years, many studies have focused on accelerating wound healing and reducing scar size by regulating the molecular mechanisms related to wound healing and scar formation. We summarized the role of these factors in wound healing and scar formation, to provide a new idea for clinical scar-free healing treatment of uterine incisions.

G-quadruplexes in cancer-related gene promoters: from identification to therapeutic targeting

INTRODUCTION

Guanine-rich DNA sequences can fold into four-stranded noncanonical secondary structures called G-quadruplexes (G4s) which are widely distributed in functional regions of the human genome, such as telomeres and gene promoter regions. Compelling evidence suggests their involvement in key genome functions such as gene expression and genome stability. Notably, the abundance of G4-forming sequences near transcription start sites suggests their potential involvement in regulating oncogenes.

AREAS COVERED

This review provides an overview of current knowledge on G4s in human oncogene promoters. The most representative G4-binding ligands have also been documented. The objective of this work is to present a comprehensive overview of the most promising targets for the development of novel and highly specific anticancer drugs capable of selectively impacting the expression of individual or a limited number of genes.

EXPERT OPINION

Modulation of G4 formation by specific ligands has been proposed as a powerful new tool to treat cancer through the control of oncogene expression. Actually, most of G4-binding small molecules seem to simultaneously target a range of gene promoter G4s, potentially influencing several critical driver genes in cancer, thus producing significant therapeutic benefits.

Molecular evolution of wound healing-related genes during cetacean secondary aquatic adaptation

The marine environment presents challenges for wound healing in cetaceans, despite their remarkable recovery abilities with minimal infections or complications. However, the molecular mechanism underlying this efficient wound healing remains underexplored. To better understand the molecular mechanisms behind wound healing in cetaceans, we investigated the evolutionary patterns of 37 wound healing-related genes in representative mammals. We found wound healing-related genes experience adaptive evolution in cetaceans: (1) Three extrinsic coagulation pathway-related genes-tissue factor (F3), coagulation factor VII (F7), and coagulation factor X (F10)-are subject to positive selection in cetaceans, which might promote efficient hemostasis after injury; positive selection in transforming growth factor-beta 2 (TGF-β2), transforming growth factor-beta 3 (TGF-β3), and platelet-derived growth factor D (PDGFD), which play immunological roles in wound healing, may help cetaceans enhance inflammatory response and tissue debridement. (2) Coagulation factor XII (F12) is the initiation factor in the intrinsic coagulation pathway. It had a premature stop codon mutation and was subjected to selective stress relaxation in cetaceans, suggesting that the early termination of F12 may help cetaceans avoid the risk of vascular blockage during diving. (3) Fibrinogen alpha chain (FGA) and FIII, which were detected to contain the specific amino acid substitutions in marine mammals, indicating similar evolutionary mechanisms might exist among marine mammals to maintain strong wound-healing ability. Thus, our research provides further impetus to study the evolution of the wound healing system in cetaceans and other marine mammals, extending knowledge of preventing coagulation disorder and atherosclerosis in humans.

The expression of platelet-derived growth factor and its receptor in canine and feline meningiomas

Feline meningiomas usually have benign biological behavior, while canine and human meningiomas are often classified as grade 2 or 3. Activation of the platelet-derived growth factor (PDGF) and its receptor signal pathway through PDGFβ/Rβ autocrine and paracrine is considered to play an important role in the tumor proliferation and malignant transformation of human meningiomas. However, there have been few studies about the expression of these molecules in canine meningiomas and no studies about their expression in feline meningiomas. We analyzed the PDGFα/Rα and PDGFβ/Rβ expression in canine and feline meningiomas by immunohistochemistry and western blotting. Immunohistochemically, most canine meningiomas showed the expression of PDGFα (42/44; 95.5%), PDGFRα (44/44; 100%) and PDGFRβ (35/44; 79.5%), and a few showed the expression of PDGFβ (8/44; 18.2%). In contrast, feline meningiomas were immunopositive for PDGFRα and PDGFRβ in all cases (14/14; 100%), while no or a few cases expressed PDGFα (0/14; 0%) and PDGFβ (2/14; 14.3%). Western blotting revealed specific bands for PDGFα, PDGFRα and PDGFRβ, but not for PDGFβ in a canine meningioma. In a feline meningioma, specific bands for PDGFRα and PDGFRβ were detected, but not for PDGFα and PDGFβ. These results suggested that canine meningiomas commonly express PDGFα/Rα, and thus autocrine or paracrine PDGFα/Rα signaling may be involved in their initiation and progression. Moreover, PDGF negativity may be related to benign biological behavior and a low histopathological grade in feline meningioma.