Platelet-Derived Exosomes and Atherothrombosis

Novel Advances in Cell-Free Therapy for Premature Ovarian Failure (POF): A Comprehensive Review

Premature ovarian failure (POF), is a condition characterized by the early decline of ovulation function. POF is a complex disorder that can be caused by various factors, and the idiopathic form represents a significant proportion of POF patients. Hormone replacement therapy (HRT) is currently considered the first-line treatment for POF. This review aims to provide a comprehensive overview of recent advancements in platelet-rich plasma (PRP), in vitro activation (IVA), stem cell therapy, exosome therapy, microRNAs, and mitochondrial targeting therapies as a promising cell-free therapeutic approach in reproductive medicine. PLT-Exos, a new generation of cells, has been used to treat POF for more than a decade and has been shown to attenuate oocyte morphology and promote the differentiation of theca cells through the upregulation of PI3K/Akt and Bcl2, as well as the downregulation of the Smad and Bax signaling pathways. This review summarizes the current state of the art in the field of PLT-Exos and discusses the advantages and limitations of their potential clinical applications.

Thrombotic events associated with immune checkpoint inhibitors and novel antithrombotic strategies to mitigate bleeding risk

Although immunotherapy is expanding treatment options for cancer patients, the prognosis of advanced cancer remains poor, and these patients must contend with both cancers and cancer-related thrombotic events. In particular, immune checkpoint inhibitors are associated with an increased risk of atherosclerotic thrombotic events. Given the fundamental role of platelets in atherothrombosis, co-administration of antiplatelet agents is always indicated. Platelets are also involved in all steps of cancer progression. Classical antithrombotic drugs can cause inevitable hemorrhagic side effects due to blocking integrin β3 bidirectional signaling, which regulates simultaneously thrombosis and hemostasis. Meanwhile, many promising new targets are emerging with minimal bleeding risk and desirable anti-tumor effects. This review will focus on the issue of thrombosis during immune checkpoint inhibitor treatment and the role of platelet activation in cancer progression as well as explore the mechanisms by which novel antiplatelet therapies may exert both antithrombotic and antitumor effects without excessive bleeding risk.

Role of Platelets and Their Interaction with Immune Cells in Venous Thromboembolism

Venous thromboembolism (VTE) represents a significant global health challenge, ranking as the third leading cause of cardiovascular-related mortality. VTE pervades diverse clinical specialties, posing substantial risks to patient well-being and imposing considerable economic strains on health care systems. While platelets have long been recognized as pivotal players in hemostasis, emerging evidence underscores their multifaceted immune functions and their capacity to engage in crosstalk with other immune cells, such as neutrophils, thereby fostering immune-related thrombosis. Notably, investigations have elucidated the pivotal role of platelets in the pathogenesis of VTE. This review provides a comprehensive overview of platelet physiology, encompassing their activation, secretion dynamics, and implications in VTE. Moreover, it delineates the impact of platelet interactions with various immune cells on the initiation and progression of VTE, explores the correlation between platelet-related laboratory markers and VTE, and elucidates the role of platelets in thrombosis regression.

Platelet-derived exosomes regulate endothelial cell inflammation and M1 macrophage polarization in coronary artery thrombosis via modulating miR-34a-5p expression

As the important factors in coronary artery thrombosis, endothelial injury and M1 macrophage polarization are closely related to the expression of miR-34a-5p. Exosomes in plasma are mainly derived from platelets and play an important role in thrombosis. Based on these facts, this study was conducted to investigate the acting mechanism of platelet-derived exosomes (PLT-exo) in the effects of endothelial injury and M1 macrophage polarization on coronary artery thrombosis. Firstly, rats were divided into the sham-operated group and the coronary microembolization (CME) group, and their plasma-derived exosomes were extracted to detect the expression of miR-34a-5p. Next, the PLT-exo were extracted from healthy volunteers and then co-cultured with ox-LDL-induced endothelial cells and LPS-induced macrophages, respectively. Subsequently, the expression of IL-1β, IL-6, TNF-α, and ICAM-1 in endothelial cells was measured, and the level of markers related to M1 macrophage polarization and Sirt1/NF-κB pathway was detected. Finally, the above indicators were examined again after PLT-exo combined with miR-34a-5p mimic were co-cultured with endothelial cells and macrophages, respectively. The results demonstrated that the expression of miR-34a-5p in the CME group was up-regulated compared with the sham-operated group. In cell experiments, PLT-exo modulated the Sirt1/NF-κB pathway by inhibiting the expression of intracellular miR-34a-5p and down-regulated the expression of IL-1β, IL-6, TNF-α, and ICAM-1 in endothelial cells and M1 macrophage polarization. After the transfection with miR-34a-5p mimic, endothelial cell inflammatory injury and M1 macrophage polarization increased to varying degrees. In conclusion, PLT-exo can alleviate coronary artery thrombosis by reducing endothelial cell inflammation and M1 macrophage polarization via inhibiting miR-34a-5p expression. In contrast, miR-34a-5p overexpression in PLT-exo may exacerbate these pathological injuries in coronary artery thrombosis.

Hydrogel-mediated delivery of platelet-derived exosomes: Innovations in tissue engineering

In this scholarly review, we conduct a thorough examination of the significant role played by platelet-derived exosomes (Plt-Exos) and hydrogels in the fields of tissue engineering and regenerative medicine. Our detailed investigation highlights the central involvement of Plt-Exos in various physiological and pathological processes, underscoring their potential contributions to diverse areas such as wound healing, neural rejuvenation, and cancer progression. Despite the promising therapeutic aspects, the notable variability in the isolation and characterization of pEVs underscores the need for a more rigorous and standardized methodology. Shifting our focus to hydrogels, they have emerged as promising biomaterials relevant to tissue engineering and regenerative medicine. Their unique characteristics, especially their chemical and physical adaptability, along with the modifiability of their biochemical properties, make hydrogels a captivating subject. These exceptional features open avenues for numerous tissue engineering applications, facilitating the delivery of essential growth factors, cytokines, and microRNAs. This analysis explores the innovative integration of Plt-Exos with hydrogels, presenting a novel paradigm in tissue engineering. Through the incorporation of Plt-Exos into hydrogels, there exists an opportunity to enhance tissue regeneration endeavors by combining the bioactive features of Plt-Exos with the restorative capabilities of hydrogel frameworks. In conclusion, the cooperative interaction between platelet-derived exosomes and hydrogels indicates a promising path in tissue engineering and regenerative medicine. Nevertheless, the successful execution of this approach requires a deep understanding of molecular dynamics, coupled with a dedication to refining isolation techniques.

[Correlation between preoperative platelet parameters and clinicopathological features of differentiated thyroid cancer]

Objective:To investigate the correlation between preoperative platelet parameters and the clinicopathological features of differentiated thyroid cancer. Methods:We retrospectively analyzed the medical records of patients with thyroid tumors admitted to Zhongda Hospital affiliated to Southeast University and healthy adults with normal physical examination results in our hospital from January 2019 to December 2020, and collected their general information and preoperative blood routine data. Patients with undifferentiated thyroid cancer, diabetes, coronary heart disease, hematological diseases, kidney diseases, autoimmune diseases, genetic diseases, infectious diseases, other systemic tumors, hepatitis or cirrhosis, or those taking anticoagulants were excluded. The exclusion criteria for healthy adults were the absence of the above diseases and normal physical examination results. Differences in platelet parameters among the three groups were compared, and the correlation between clinicopathological characteristics of thyroid cancer, accompanying cervical lymph node metastasis, and platelet parameters of patients was analyzed. A multivariate logistic regression model was used to analyze the risk factors of thyroid cancer with cervical lymph node metastasis. Results:A total of 117 cases of differentiated thyroid cancer were collected, including 33 males and 84 females, with an average age of （41.64±12.25） years; 46 patients had benign thyroid tumors, including 15 males and 31 females, with an average age of （41.35±12.52） years; 50 healthy adults with normal physical examination results in our hospital during the same period were also included, including 18 males and 32 females, with an average age of（42.02±9.62） years, without underlying diseases. The platelet count of the differentiated thyroid cancer group was higher than that of the benign thyroid tumor group（t=-2.219, P=0.028） and the normal control group（t=2.069, P=0.04）, while the platelet distribution width of the differentiated thyroid cancer group was lower than that of the benign thyroid tumor group（t=2.238, P=0.027） and the normal control group（t=-2.618, P=0.002）. These differences were statistically significant. Preoperative age ≤45 years（χ²=4.225, P=0.04）, tumor diameter>1 cm（χ²=4.415, P=0.036）, PLT（t=-4.018, P<0.01） increase, and PDW（t=4.568, P<0.01） decrease were significantly correlated with cervical lymph node metastasis of thyroid cancer and had statistical significance. Univariate analysis showed that age ≤45 years（OR=0.447, 95%CI 0.206-0.970, P=0.042）, tumor diameter>1 cm（OR=2.3, 95%CI 1.050-5.039, P=0.037）, PLT（OR=1.012, 95%CI 1.005-1.019, P=0.001）, and PDW（OR=0.693, 95%CI 0.518-0.827, P<0.01） were risk factors for cervical lymph node metastasis of thyroid cancer. The results of multifactorial logistic regression analysis showed that PLT（OR=1.008, 95%CI 1.001-1.016, P=0.026） and PDW（OR=0.692, 95%CI 0.564-0.848, P<0.01） were independent risk factors for thyroid cancer with cervical lymph node metastasis. Conclusion:PLT and PDW may be useful predictive factors for the differentiation of thyroid cancer malignancy and central lymph node metastasis.

A role for platelets in metabolic reprogramming of tumor-associated macrophages

Cancer incidence and mortality are growing worldwide. With a lack of optimal treatments across many cancer types, there is an unmet need for the development of novel treatment strategies for cancer. One approach is to leverage the immune system for its ability to survey for cancer cells. However, cancer cells evolve to evade immune surveillance by establishing a tumor microenvironment (TME) that is marked by remarkable immune suppression. Macrophages are a predominant immune cell within the TME and have a major role in regulating tumor growth. In the TME, macrophages undergo metabolic reprogramming and differentiate into tumor-associated macrophages (TAM), which typically assume an immunosuppressive phenotype supportive of tumor growth. However, the plasticity of macrophage biology offers the possibility that macrophages may be promising therapeutic targets. Among the many determinants in the TME that may shape TAM biology, platelets can also contribute to cancer growth and to maintaining immune suppression. Platelets communicate with immune cells including macrophages through the secretion of immune mediators and cell-cell interaction. In other diseases, altering platelet secretion and cell-cell communication has been shown to reprogram macrophages and ameliorate inflammation. Thus, intervening on platelet-macrophage biology may be a novel therapeutic strategy for cancer. This review discusses our current understanding of the interaction between platelets and macrophages in the TME and details possible strategies for reprogramming macrophages into an anti-tumor phenotype for suppressing tumor growth.

Association between Intestinal Microecological Changes and Atherothrombosis

Atherosclerosis (AS) is a chronic inflammatory disease of large- and medium-sized arteries that causes ischemic heart disease, strokes, and peripheral vascular disease, collectively called cardiovascular disease (CVD), and is the leading cause of CVD resulting in a high rate of mortality in the population. AS is pathological by plaque development, which is caused by lipid infiltration in the vessel wall, endothelial dysfunction, and chronic low-grade inflammation. Recently, more and more scholars have paid attention to the importance of intestinal microecological disorders in the occurrence and development of AS. Intestinal G-bacterial cell wall lipopolysaccharide (LPS) and bacterial metabolites, such as oxidized trimethylamine (TMAO) and short-chain fatty acids (SCFAs), are involved in the development of AS by affecting the inflammatory response, lipid metabolism, and blood pressure regulation of the body. Additionally, intestinal microecology promotes the progression of AS by interfering with the normal bile acid metabolism of the body. In this review, we summarize the research on the correlation between maintaining a dynamic balance of intestinal microecology and AS, which may be potentially helpful for the treatment of AS.

The role of extracellular vesicles in intercellular communication in human reproduction

Embryo-maternal cross-talk has emerged as a vitally important process for embryo development and implantation, which is driven by secreted factors and extracellular vesicles (EVs). The EV cargo of bioactive molecules significantly influences target cells and primes them for critical stages of reproductive biology, including embryo development, adhesion, and implantation. Recent research has suggested that EVs and their cargo represent a powerful non-invasive tool that can be leveraged to assess embryo and maternal tissue quality during assisted reproduction treatments. Here, we review the current scientific literature regarding the intercellular cross-talk between embryos and maternal tissues from fertilization to implantation, focusing on human biology and signaling mechanisms identified in animal models.

Research landscape of exosomes in platelets from 2000 to 2022: A bibliometric analysis

Background

Blood-derived exosomes are involved in developing multiple pathological processes, with platelets being the most well-known source. Related studies have become an area of research with significant value and potential. However, no bibliometric studies in this field have yet been identified. We aimed to analyze the hotspots and academic trends of platelet exosome research through bibliometric visualization to actively grasp the research base in this field and track its developmental orientation.

Methods

From 2000 to 2022, we screened all relevant publications on platelet exosome-related research from the Web of Science database, generated knowledge maps using VOSviewer and CiteSpace software, and analyzed research trends in the field.

Results

A total of 722 articles were screened for inclusion based on the search strategy. The number of articles on exosome studies in platelets has expanded vastly. The USA and the People's Republic of China contributed substantially among 69 countries or regions. Amsterdam University and Semmelweis University are the research institutions with the most publications. The most studied and co-cited journals were the International Journal of Molecular Sciences and the Journal of Extracellular Vesicles. We identified 4,598 authors, with Nieuwland Rienk having the highest number of articles and Bruno Stefania having the most cited publications. Keywords of great interest include "thrombosis," "anti-inflammatory," "anti-apoptosis," "angiogenesis," "microparticles," "miRNAs," "stem cells," and "biomarkers," which are key research areas for future development.

Conclusion

We used bibliometric and visualization methods to identify hotspots and trends in platelet exosome research. Platelet exosome research is widely expanding. Future research will most likely focus on "thrombosis," "anti-inflammatory," "anti-apoptosis," "angiogenesis," "microparticles," "miRNAs," "stem cells," and "biomarkers."