Emerging role of extracellular vesicles in diabetic retinopathy.

Diabetic retinopathy (DR), a complex complication of diabetes mellitus (DM), is a leading cause of adult blindness. Hyperglycemia triggers DR, resulting in microvascular damage, glial apoptosis, and neuronal degeneration. Inflammation and oxidative stress play crucial roles during this process. Current clinical treatments for DR primarily target the advanced retinal disorder but offer limited benefits with inevitable side effects. Extracellular vesicles (EVs) exhibit unique morphological features, contents, and biological properties and can be found in cell culture supernatants, various body fluids, and tissues. In DR, EVs with specific cargo composition would induce the reaction of receptor cell once internalized, mediating cellular communication and disease progression. Increasing evidence indicates that monitoring changes in EV quantity and content in DR can aid in disease diagnosis and prognosis. Furthermore, extensive research is investigating the potential of these nanoparticles as effective therapeutic agents in preclinical models of DR. This review explores the current understanding of the pathological effects of EVs in DR development, discusses their potential as biomarkers and therapeutic strategies, and paves the way for further research and therapeutic advancements.

Tandem mass tag-based quantitative proteomics analyses of the spermatogenesis-ameliorating effect of Youjing granule on rats.

RATIONALE: Male infertility is a common reproductive system disease manifested as aberrant spermatogenesis and identified as "kidney deficiency and dampness" in Chinese traditional medicine. Youjing granule (YG) is a Chinese material medica based on tonifying kidneys and removing dampness. It has proven to be able to regulate semen quality in clinical application, but the underlying mechanism has not been clarified. METHODS: Using serum containing YG to treat primarily cultured spermatogonial stem cells (SSCs), the apoptotic rate and mitosis phase ratio of SSCs were measured. The liquid chromatography-tandem mass spectrometry with tandem mass tags method was applied for analyzing the serum of rats treated with YG/distilled water, and proteomic analyses were performed to clarify the mechanisms of YG. RESULTS: Totally, 111 proteins in YG-treated serum samples were differentially expressed compared with control groups, and 43 of them were identified as potential target proteins, which were further annotated based on their enrichment in Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways. Proteomic analyses showed that the mechanisms of YG may involve regulation of glycolysis, gluconeogenesis and nucleotide-binding and oligomerization domain-like receptor signaling pathway. In addition, RhoA and Lamp2 were found to be possible responders of YG through reviewing the literature. CONCLUSIONS: The results demonstrate that our serum proteomics platform is clinically useful in understanding the mechanisms of YG.

A Dual Role of Mesenchymal Stem Cell Derived Small Extracellular Vesicles on TRPC6 Protein and Mitochondria to Promote Diabetic Wound Healing.

Diabetic wounds exhibit delayed and incomplete healing, usually due to vascular and nerve damage. Dysregulation of cellular Ca2+ homeostasis has recently been shown to be closely related to insulin resistance and type 2 diabetes mellitus. However, the involvement of this dysregulation in diabetic wound complications remains unknown. In this study, we found calcium dysregulation in patients with diabetic ulcers via tissue protein profiling. High glucose and glucometabolic toxicant stimulation considerably impaired the function of TRPC6, a pore subunit of transient receptor potential channels mediating Ca2+ influx, and mitochondria, which regulate calcium cycling and metabolism. Furthermore, we found that mesenchymal stem cell (MSC)-derived small extracellular vesicles (MSC-sEVs) could play a dual role in restoring the function of TRPC6 and mitochondria by delivering transcription factor SP2 and deubiquitinating enzyme USP9, respectively. MSC-sEVs could transfer SP2 that activated TRPC6 expression by binding to its specific promoter regions (-1519 to -1725 bp), thus recovering Ca2+ influx and downstream pathways. MSC-sEVs also promoted mitophagy to restore mitochondrial function by transporting USP9 that stabilized the expression of Parkin, a major player in mitophagy, thereby guaranteeing Ca2+ efflux and avoidance of Ca2+ overload. Targeting the regulation of calcium homeostasis provides a perspective for understanding diabetic wound healing, and the corresponding design of MSC-sEVs could be a potential therapeutic strategy.

Ectopic pregnancy adjacent to iliac vessels managed successfully by minimally invasive treatment using local methotrexate injection: An extremely rare case and literature review.

A case report of successfully treated retroperitoneal ectopic pregnancy (REP) is presented. A 36-year-old woman, gravida 3, para 2, was admitted to hospital for suspected ectopic pregnancy with light vaginal bleeding and mild abdominal pain for 3 days at 45 days of gestation by the last menstrual period.Multiple transvaginal ultrasonography and two times laparoscopic probes led to the diagnosis of REP located to the iliac blood vessels closely. Eventually the patient was cured with the treatment using local methotrexate injection under real-time ultrasound guidance and systemic methotrexate administration. We also summarized another 31 cases of REP to further understand this disease, sharing them to arouse clinical attention for the diagnosis and treatment of REP timely.

Kaempferol has potential anti-coronavirus disease 2019 (COVID-19) targets based on bioinformatics analyses and pharmacological effects on endotoxin-induced cytokine storm.

COVID-19 has infected 272 million patients and caused 5.33 million deaths around the world, and it remains the main global threat. Previous studies revealed that Chinese traditional medicine is an effective treatment for COVID-19 infection. This study aims to reveal the pharmacological effects of kaempferol, which is the active component of Radix Bupleuri and Tripterygii Radix, and potential mechanisms for the treatment of COVID-19. Here, we employed the bioinformatics methods to filter the anti-COVID-19 candidate genes of kaempferol, which mainly enriched in inflammation (TNF, JUN, etc.) and virus infection (AKT1, JNK, etc.). The Transcription levels of AKT1, JNK and JUN were significantly reduced by kaempferol treatment in the LPS-activated macrophages. In addition, kaempferol reduced the secretion of inflammatory factors by LPS-stimulated macrophages, inhibited MAPK/NF-κB signaling and regulated macrophage polarization to M2 type in vitro, and suppressed endotoxin-induced cytokine storm and improved survival in mice. Molecular docking analysis demonstrated that kaempferol was probable to bind the COVID-19 protein 5R84 and formatted hydrogen bond with the residues, the free binding energy of which was lower than the original ligand. In summary, our current work indicates that kaempferol has anti-COVID-19 potential through the reduction of COVID-19-induced body dysfunction and molecule-protein interaction, and bioinformatics results clarify that some of these key target genes might serve as potential molecular markers for detecting COVID-19.

Skin cell-derived extracellular vesicles: a promising therapeutic strategy for cutaneous injury.

Wound healing refers to the healing process that occurs after the skin and other tissues are separated or damaged by internal or external forces. It is a complex combination of tissue regeneration, granulation tissue hyperplasia, and scar formation, and shows the synergistic effects of these processes. After skin damage, the environment around the wound and the cells at site of the damage respond immediately, and a range of cytokines and growth factors are released. In cutaneous injury, extracellular vesicle (EV) signaling plays a vital role in the healing process via paracrine and endocrine mechanisms. EVs are natural intercellular and inter-organ communication tools that carry various bioactive substances for message exchange. Stem cells and stem cell EVs facilitate tissue repair, showing promising potential in regenerative medicine. Nevertheless, EVs derived from specific skin tissue cells, such as epidermal cells, fibroblasts, vascular endothelial cells and inflammatory cells, also play important roles in cutaneous tissue repair. Here, we describe the characteristics of wound healing, concentrating on the production and functions of EVs derived from specific skin cells, and provide new ideas for wound therapy using EVs.

Small extracellular vesicles isolation and separation: Current techniques, pending questions and clinical applications.

Extracellular vesicles, especially small extracellular vesicles (sEVs) are now accepted as important messengers in cell-to-cell communication and as a promising drug delivery platform. They are involved in nearly all physiological and pathological processes and are involved in disease diagnosis and therapy. However, their heterogeneity of physicochemical properties and functions is not fully understood, which hinders further clinical applications. To obtain highly bioactive sEVs with both high yield and purity, will certainly facilitate their future study and application. This review informs up-to-date research on frequently-used and cutting-edge technologies of sEVs isolation and makes a deep comparison and analysis of different methods, including their advantages, limitations and applications. Pending questions about the inherent property of these small vesicles as well as isolation strategies are discussed. Additionally, an overview of their applications in disease diagnosis and treatment, including some of the on-going clinical trials, are also reviewed.

Youjing granules ameliorate spermatogenesis in rats through regulating the prolifereation of spermatogonial stem cells.

Male infertility has evolved from a common reproductive system disease to a major social issue. Youjing granule (YG) is a Chinese medicinal material used as a therapy method for tonifying the kidneys and removing dampness due to its pathogenic characteristics. YG has been shown to regulate sperm quality in clinical trials, but the underlying mechanism is not fully understood. The present study was aimed to explore the protective effects and mechanism of action of YG on male reproductive system damage caused by methyl methane sulfonate (MMS). We first established an infertility model of rats through oral administration of MMS and then treated with YG. To determine the effect of YG, spermatogenesis, microvascular density, and secretory function of Leydig cells and Sertoli cells in rats were assessed. Spermatogonial stem cells (SSCs) were co-cultured with mouse embryo fibroblast (MEF) cells as an in vitro cell model before exposure to serum containing YG. Furthermore, the proliferation and apoptosis of SSCs were measured. Results indicated that YG increased the expression of self-renewal and proliferation-related molecules such as glial cell line derived neurotrophic factor (GDNF) and fibroblast growth factor-2 (FGF2), and improved the quality of sperm and the proliferation of SSCs. In conclusion, YG may protect spermatogenetic function of rats through regulating the proliferation and self-renewal of SSCs.

Tea Ingredients Have Anti-coronavirus Disease 2019 (COVID-19) Targets Based on Bioinformatics Analyses and Pharmacological Effects on LPS-Stimulated Macrophages.

Coronavirus disease 2019 (COVID-19) is a contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that caused millions of deaths and lacks treatment. Although several studies have focused on the major component of green tea, epigallocatechin 3-gallate (EGCG), which is efficient in preventing COVID-19, systemic analyses of the anti-COVID-19 potential of green tea remain insufficient. Here, we co-analyzed the target genes of tea ingredients and COVID-19 signature genes and found that epigallocatechin 3-acetalbehyde was capable of reversing the major molecular processes of COVID-19 (MAPK and NF-κB activation). These findings were further supported by Western blotting (WB), immunofluorescence, and quantitative polymerase chain reaction (qPCR) in LPS-stimulated macrophages. Moreover, using molecular docking analysis, we identified three tea ingredients ((-)-catechin gallate, D-(+)-cellobiose, and EGCG) that may interact with the vital SARS-CoV-2 protein, 5R84, compared with the qualified 5R84 ligand WGS. Thus, our results indicated that tea ingredients have the potential to treat COVID-19 by suppressing the COVID-19 signature genes and interacting with the vital SARS-CoV-2 protein.

Stem Cell-Based Therapy for Diabetic Foot Ulcers.

Diabetic foot ulcer has become a worldwide clinical medical challenge as traditional treatments are not effective enough to reduce the amputation rate. Therefore, it is of great social significance to deeply study the pathogenesis and biological characteristics of the diabetic foot, explore new treatment strategies and promote their application. Stem cell-based therapy holds tremendous promise in the field of regenerative medicine, and its mechanisms include promoting angiogenesis, ameliorating neuroischemia and inflammation, and promoting collagen deposition. Studying the specific molecular mechanisms of stem cell therapy for diabetic foot has an important role and practical clinical significance in maximizing the repair properties of stem cells. In addition, effective application modalities are also crucial in order to improve the survival and viability of stem cells at the wound site. In this paper, we reviewed the specific molecular mechanisms of stem cell therapy for diabetic foot and the extended applications of stem cells in recent years, with the aim of contributing to the development of stem cell-based therapy in the repair of diabetic foot ulcers.

Exosomes: Emerging Cell-Free Based Therapeutics in Dermatologic Diseases.

Exosomes are lipid bilayer vesicles released by multiple cell types. These bioactive vesicles are gradually becoming a leading star in intercellular communication involving in various pathological and physiological process. Exosomes convey specific and bioactive transporting cargos, including lipids, nucleic acids and proteins which can be reflective of their parent cells, rendering them attractive in cell-free therapeutics. Numerous findings have confirmed the crucial role of exosomes in restraining scars, burning, senescence and wound recovery. Moreover, the biology research of exosomes in cutting-edge studies are emerging, allowing for the development of particular guidelines and quality control methodology, which favor their possible application in the future. In this review, we discussed therapeutic potential of exosomes in different relevant mode of dermatologic diseases, as well as the various molecular mechanisms. Furthermore, given the advantages of favorable biocompatibility and transporting capacity, the bioengineering modification of exosomes is also involved.

The Utility of Exosomes in Diagnosis and Therapy of Diabetes Mellitus and Associated Complications.

Diabetes mellitus and the associated complications are metabolic diseases with high morbidity that result in poor quality of health and life. The lack of diagnostic methods for early detection results in patients losing the best treatment opportunity. Oral hypoglycemics and exogenous insulin replenishment are currently the most common therapeutic strategies, which only yield temporary glycemic control rather than curing the disease and its complications. Exosomes are nanoparticles containing bioactive molecules reflecting individual physiological status, regulating metabolism, and repairing damaged tissues. They function as biomarkers of diabetes mellitus and diabetic complications. Considering that exosomes are bioactive molecules, can be obtained from body fluid, and have cell-type specificity, in this review, we highlight the multifold effects of exosomes in the pathology and therapy of diabetes mellitus and diabetic complications.

Calcium Channels: Noteworthy Regulators and Therapeutic Targets in Dermatological Diseases.

Dysfunctional skin barrier and impaired skin homeostasis may lead to or aggravate a series of dermatologic diseases. A large variety of biological events and bioactive molecules are involved in the process of skin wound healing and functional recovery. Calcium ions (Ca2+) released from intracellular stores as well as influx through plasma membrane are essential to skin function. Growing evidence suggests that calcium influx is mainly regulated by calcium-sensing receptors and channels, including voltage-gated, transient potential receptor, store-operated, and receptor-operated calcium channels, which not only maintain cellular Ca2+ homeostasis, but also participate in cell proliferation and skin cell homeostasis through Ca2+-sensitive proteins such as calmodulin (CaM). Furthermore, distinct types of Ca2+ channels not merely work separately, they may work concertedly to regulate cell function. In this review, we discussed different calcium-sensing receptors and channels, including voltage-gated, transient receptor potential, store-operated, and receptor-operated calcium channels, particularly focusing on their regulatory functions and inherent interactions as well as calcium channels-related reagents and drugs, which is expected to bridge basic research and clinical applications in dermatologic diseases.

3,3'-Diindolylmethane Promotes Gastric Cancer Progression via ß-TrCP-Mediated NF-κB Activation in Gastric Cancer-Derived MSCs.

Gastric cancer is a malignant tumor characterized by high morbidity and invasion. Surgery combined with chemo-radiotherapy is the most common treatment for gastric cancer, while multiple drug resistance always results in treatment failure. Once the anti-tumor drugs enter the tumor foci, tumor cells as well as those found in the microenvironment are affected. However, the effects of drugs on tumor microenvironment (TME) are easily overlooked. In this study, we investigated the effects of the anti-cancer drug 3,3'-diindolylmethane (DIM) on gastric cancer-derived mesenchymal stem cells (GC-MSCs) and their subsequent impact on cancer progression. Surprisingly, we found that the therapeutic concentration of DIM upregulated the expression level of tumor-related factors such as CCL-2, IL-6, and IL-8 in GC-MSCs. The conditioned medium of DIM-treated GC-MSCs promoted the proliferation, invasion, and migration of gastric cancer cells in vitro and tumor growth in vivo. Mechanistically, DIM enhanced the expression of ß-TrCP, an E3 ubiquitin ligase leading to IκBα degradation and NF-κB activation in GC-MSCs. The ß-TrCP knockdown partially eliminated positive results caused by DIM. Our results showed that the therapeutic dosage of DIM induced cell death in cancer cells, while enhancing MSC paracrine functions in the stroma to offset the original DIM effect on cancer cells. These findings provide a new mechanism of anti-cancer drug resistance and remind us to adjust the chemotherapeutic scheme by combining the anti-cancer drug with an appropriate signaling pathway inhibitor to block the side effects of drug on targeted TME cells.

HucMSC exosome-delivered 14-3-3ζ alleviates ultraviolet radiation-induced photodamage via SIRT1 pathway modulation.

Exosomes derived from human umbilical cord mesenchymal stem cells (hucMSC-ex) are nano-sized membrane-bound vesicles that have been reported to facilitate skin regeneration and repair. However, the roles played by hucMSC-ex in ultraviolet (UV) radiation-induced skin photodamage and the underlying mechanisms remain unknown. To investigate the functions of hucMSC-ex in a rat model of acute skin photodamage, immunofluorescence and immunohistochemical staining, quantitative real-time-polymerase chain reaction (qRT-PCR), western blot, and gene silencing assays were performed. We found that the in vivo subcutaneous injection of hucMSC-ex elicited antioxidant and anti-inflammatory effects against UV radiation-induced DNA damage and apoptosis. Further studies showed that the sirtuin 1 (SIRT1) expression level in skin keratinocytes (HaCaT) decreased in a time- and dose-dependent manner under in vitro UV radiation induced-oxidative stress conditions, which could be reversed by treatment with hucMSC-ex. The activation of SIRT1 significantly attenuated UV- and H2O2-induced cytotoxic damage by inhibiting oxidative stress and promoting the activation of autophagy. Our study found that 14-3-3ζ protein, which was delivered by hucMSC-ex, exerted a cytoprotective function via the modulation of a SIRT1-dependent antioxidant pathway. Collectively, our findings indicated that hucMSC-ex might represent a new potential agent for preventing or treating UV radiation-induced skin photodamage and aging.

Resveratrol improves human umbilical cord-derived mesenchymal stem cells repair for cisplatin-induced acute kidney injury.

Human umbilical cord-derived mesenchymal stem cells (hucMSCs) are a promising tool for damaged tissues repair, especially for the kidney. However, their efficacy requires improvement. In order to optimize the clinical utility of hucMSCs, we adopted a strategy of treating hucMSCs with 20 µmol/L of resveratrol (Res-hucMSCs), applying it in a cisplatin-induced acute kidney injury model. Interestingly, we found that Res-hucMSCs exhibited a more efficient repairing effect than did hucMSCs. Resveratrol-promoted hucMSCs secreted platelet-derived growth factor-DD (PDGF-DD) into renal tubular cells resulting in downstream phosphorylation of extracellular signal-regulated kinase (ERK), which inhibited renal tubular cells apoptosis. In contrast, PDGF-DD knockdown impaired the renal protection of Res-hucMSCs. In addition, angiogenesis induced by PDGF-DD in endothelial cells was also involved in the renal protection of Res-hucMSCs. The conditioned medium of Res-hucMSCs accelerated proliferation and migration of vascular endothelial cells in vitro and CD31 was in a high-level expression in Res-hucMSCs group in vivo. Nevertheless, the angiogenesis was abrogated when Res-hucMSCs were treated with PDGF-DD siRNA. In conclusion, our findings showed that resveratrol-modified hucMSCs activated ERK pathway in renal tubular cells and promoted angiogenesis in endothelial cells via paracrine PDGF-DD, which could be a novel strategy for enhancing the therapy efficacy of hucMSCs in cisplatin-induced kidney injury.

Human Mesenchymal Stem Cell Derived Exosomes Alleviate Type 2 Diabetes Mellitus by Reversing Peripheral Insulin Resistance and Relieving ß-Cell Destruction.

Exosomes are nanosized extracellular vesicles (EVs) that show great promise in tissue regeneration and injury repair as mesenchymal stem cell (MSC). MSC has been shown to alleviate diabetes mellitus (DM) in both animal models and clinical trials. In this study, we aimed to investigate whether exosomes from human umbilical cord MSC (hucMSC-ex) have a therapeutic effect on type 2 DM (T2DM). We established a rat model of T2DM using a high-fat diet and streptozotocin (STZ). We found that the intravenous injection of hucMSC-ex reduced blood glucose levels as a main paracrine approach of MSC. HucMSC-ex partially reversed insulin resistance in T2DM indirectly to accelerate glucose metabolism. HucMSC-ex restored the phosphorylation (tyrosine site) of the insulin receptor substrate 1 and protein kinase B in T2DM, promoted expression and membrane translocation of glucose transporter 4 in muscle, and increased storage of glycogen in the liver to maintain glucose homeostasis. HucMSC-ex inhibited STZ-induced ß-cell apoptosis to restore the insulin-secreting function of T2DM. Taken together, exosomes from hucMSC can alleviate T2DM by reversing peripheral insulin resistance and relieving ß-cell destruction, providing an alternative approach for T2DM treatment.

3,3'-Diindolylmethane stimulates exosomal Wnt11 autocrine signaling in human umbilical cord mesenchymal stem cells to enhance wound healing.

Human umbilical cord-derived mesenchymal stem cells (hucMSCs) are suggested as a promising therapeutic tool in regenerative medicine, however, their efficacy requires improvement. Small molecules and drugs come up to be a convenient strategy in regulating stem cells fate and function. Here, we evaluated 3,3'-diindolylmethane (DIM), a natural small-molecule compound involved in the repairing effects of hucMSCs on a deep second-degree burn injury rat model. HucMSCs primed with 50 µM of DIM exhibited desirable repairing effects compared with untreated hucMSCs. DIM enhanced the stemness of hucMSCs, which was related to the activation of Wnt/ß-catenin signaling. ß-catenin inhibition impaired the healing effects of DIM-primed hucMSCs (DIM-hucMSCs) in vivo. Moreover, we demonstrated that DIM upregulated Wnt11 expression in hucMSC-derived exosomes. Wnt11 knockdown inhibited ß-catenin activation and stemness induction in DIM-hucMSCs and abrogated their therapeutic effects in vivo. Thus, our findings indicate that DIM promotes the stemness of hucMSCs through increased exosomal Wnt11 autocrine signaling, which provides a novel strategy for improving the therapeutic effects of hucMSCs on wound healing.

Exosomes derived from gastric cancer cells activate NF-κB pathway in macrophages to promote cancer progression.

Exosomes are nano-sized membrane vesicles secreted by both normal and cancer cells. Emerging evidence indicates that cancer cells derived exosomes contribute to cancer progression through the modulation of tumor microenvironment. However, the effects of exosomes derived from gastric cancer cells on macrophages are not well understood. In this study, we investigated the biological role of gastric cancer cells derived exosomes in the activation of macrophages. We demonstrated that gastric cancer cells derived exosomes activated macrophages to express increased levels of proinflammatory factors, which in turn promoted tumor cell proliferation and migration. In addition, gastric cancer cells derived exosomes remarkably upregulated the phosphorylation of NF-κB in macrophages. Inhibiting the activation of NF-κB reversed the upregulation of proinflammatory factors in macrophages and blocked their promoting effects on gastric cancer cells. Moreover, we found that gastric cancer cells derived exosomes could also activate macrophages from human peripheral blood monocytes through the activation of NF-κB. In conclusion, our results suggest that gastric cancer cells derived exosomes stimulate the activation of NF-κB pathway in macrophages to promote cancer progression, which provides a potential therapeutic approach for gastric cancer by interfering with the interaction between exosomes and macrophages in tumor microenvironment.