Adipose Tissue Exosomal Proteomic Profile Reveals a Role on Placenta Glucose Metabolism in Gestational Diabetes Mellitus

Extracellular Vesicles and Pregnancy-Related Hypertensive Disorders: A Descriptive Review on the Possible Implications "From Bench to Bedside"

Pregnancy involves extracellular vesicles (EVs) through mechanisms that are poorly understood to date. Furthermore, it is not surprising that EVs may also be involved in the pathophysiology of pre-eclampsia (PE) and gestational hypertension, two clinical conditions with high morbidity and mortality, given their capacity to mediate intracellular communications and regulate inflammation and angiogenesis. We searched major online scientific search engines (PubMed, Google Scholar, Scopus, WES, Embase, etc.) using the terms "Preeclampsia", "Pregnancy", "Hypertension", "Pregnancy-related hypertension", "Extracellular vesicles", "Biomarkers", "Gestation" AND "Obstetrics". Finding potential early biomarkers of risk or illness progression would be essential for the optimum care of expectant mothers with the aforementioned conditions. Nevertheless, none of the various screening assays that have been discovered recently have shown high predictive values. The analysis of EVs in the peripheral blood starting from the first trimester of pregnancy may hold great promise for the possible correlation with gestational hypertension problems and represent a marker of the early stages of the disease. EVs use may be a novel therapeutic approach for the management of various illnesses, as well. In order to define EVs' function in the physiopathology of pregnancy-associated hypertension and PE, as well as their potential as early biomarkers and therapeutic tools, we have compiled the most recent data in this review.

Gestational Diabetes Mellitus: Mechanisms Underlying Maternal and Fetal Complications

Gestational diabetes mellitus (GDM) affects over 10% of all pregnancies, both in Korea and worldwide. GDM not only increases the risk of adverse pregnancy outcomes such as preeclampsia, preterm birth, macrosomia, neonatal hypoglycemia, and shoulder dystocia, but it also significantly increases the risk of developing postpartum type 2 diabetes mellitus and cardiovascular disease in the mother. Additionally, GDM is linked to a higher risk of childhood obesity and diabetes in offspring, as well as neurodevelopmental disorders, including autistic spectrum disorder. This review offers a comprehensive summary of clinical epidemiological studies concerning maternal and fetal complications and explores mechanistic investigations that reveal the underlying pathophysiology.

Updates on neonatal cell and novel therapeutics: Proceedings of the Second Neonatal Cell Therapies Symposium (2024)

Cell therapies as treatments for neonatal conditions have attracted significant research and parent interest over the last two decades. Mesenchymal stromal cells, umbilical cord blood cells and neural stem cells translate from lab, to preclinical and into clinical trials, with contributions being made from all over the world. Effective and timely translation involves frequent reflection and consultation from research-adjacent fields (i.e. cell therapies for cerebral palsy, adult neurology, companies, and regulatory bodies) as well as meaningful involvement of people with lived experience. Progress to date suggests that aligning outcome and data reporting in later phase clinical trials will support our sector, as well as involving industry partners for streamlined solutions in cell manufacturing, commercialisation and regulatory processes. Importantly, our field can also benefit from resource sharing and research collaboration in novel drug therapies, small molecules and extracellular vesicles as we attempt to bridge preclinical and clinical research. In this review, we present highlights and learnings from the second Neonatal Cell Therapies Symposium (2024), held in Sydney, Australia. IMPACT: Multiple cell therapy candidates have advanced through preclinical and clinical trials in neonatology, showing promising feasibility, safety and efficacy. Effective and timely translation is enabled by collaboration across research-adjacent fields, commercial partnerships, harmonising research outcomes and meaningful involvement of people with lived experience. Progress on the potential utility of cell therapies for neonatal conditions and further translational considerations are discussed in this paper.

Sirtuins and Their Implications in the Physiopathology of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) imposes serious short- and long-term health problems for the mother and her child. An effective therapeutic that can reduce the incidence of GDM and improve long-term outcomes is a major research priority and is very important for public health. Unfortunately, despite numerous studies, the molecular mechanisms underlying GDM are not fully defined and require further study. Chronic low-grade inflammation, oxidative stress, and insulin resistance are central features of pregnancies complicated by GDM. There is evidence of the involvement of sirtuins, which are NAD+-dependent histone deacetylases, in energy metabolism and inflammation. Taking these facts into consideration, the role of sirtuins in the pathomechanism of GDM will be discussed.

Ucp1 Ablation Improves Skeletal Muscle Glycolytic Function in Aging Mice

Muscular atrophy is among the systematic decline in organ functions in aging, while defective thermogenic fat functionality precedes these anomalies. The potential crosstalk between adipose tissue and muscle during aging is poorly understood. In this study, it is showed that UCP1 knockout (KO) mice characterized deteriorated brown adipose tissue (BAT) function in aging, yet their glucose homeostasis is sustained and energy expenditure is increased, possibly compensated by improved inguinal adipose tissue (iWAT) and muscle functionality compared to age-matched WT mice. To understand the potential crosstalk, RNA-seq and metabolomic analysis were performed on adipose tissue and muscle in aging mice and revealed that creatine levels are increased both in iWAT and muscle of UCP1 KO mice. Interestingly, molecular analysis and metabolite tracing revealed that creatine biosynthesis is increased in iWAT while creatine uptake is increased in muscle in UCP1 KO mice, suggesting creatine transportation from iWAT to muscle. Importantly, creatine analog β-GPA abolished the differences in muscle functions between aging WT and UCP1 KO mice, while UCP1 inhibitor α-CD improved muscle glycolytic function and glucose metabolism in aging mice. Overall, these results suggested that iWAT and skeletal muscle compensate for declined BAT function during aging via creatine metabolism to sustain metabolic homeostasis.

Extracellular Vesicles as Biomarkers of Pregnancy Complications

Extracellular vesicles (EVs) are double-membrane vesicles that facilitate intercellular communication and play a pivotal role in both physiological and pathological processes. A substantial body of evidence suggests that EVs play a role in the pathogenesis of various pregnancy complications. Because EVs can be detected in the peripheral blood, they are potential biomarkers for the early diagnosis of pregnancy complications and foetal developmental disorders. The majority of studies have demonstrated a correlation between alterations in the concentration of EVs and changes in their contents and the occurrence of pregnancy complications. Despite the current limitations in establishing a clear link between these findings and the pathogenesis of the disease, as well as the lack of sufficient evidence to support their use in clinical practice, it is noteworthy to highlight the potential role of specific miRNAs carried by EVs in the development of pregnancy complications. These include miR-210 and miR-136-5p for pre-eclampsia and gestational diabetes mellitus, miR-155, miR-26b-5p, miR-181a-5p, miR-495 and miR-374c for pre-eclampsia and preterm birth. The following miRNAs have been identified as potential biomarkers for preterm birth and gestational diabetes mellitus: miR-197-3p and miR-520h, miR-1323, miR-342-3p, miR-132-3p, miR-182-3p, miR-517-3p, miR-222-3p, miR-16-5p and miR-126-3p. Additionally, miR-127-3p has been linked to foetal growth restriction and preterm birth. Nevertheless, it would be premature to propose that EVs can be employed as biomarkers for pregnancy complications. Further research and the accumulation of results obtained using the methods proposed in the MISEV2023 guidelines will enable a definitive conclusion to be reached.

The role of microRNAs in pregnancies complicated by maternal diabetes

With the global prevalence of diabetes increasing, more people of reproductive age are experiencing hyperglycaemic pregnancies. Maternal Type 1 (T1DM) or Type 2 (T2DM) diabetes mellitus, and gestational diabetes mellitus (GDM) are associated with maternal cardiovascular and metabolic complications. Pregnancies complicated by maternal diabetes also increase the risk of short- and long-term health complications for the offspring, including altered fetal growth and the onset of T2DM and cardiometabolic diseases throughout life. Despite advanced methods for improving maternal glucose control, the prevalence of adverse maternal and offspring outcomes associated with maternal diabetes remains high. The placenta is a key organ at the maternal-fetal interface that regulates fetal growth and development. In pregnancies complicated by maternal diabetes, altered placental development and function has been linked to adverse outcomes in both mother and fetus. Emerging evidence suggests that microRNAs (miRNAs) are key molecules involved in mediating these changes. In this review, we describe the role of miRNAs in normal pregnancy and discuss how miRNA dysregulation in the placenta and maternal circulation is associated with suboptimal placental development and pregnancy outcomes in individuals with maternal diabetes. We also discuss evidence demonstrating that miRNA dysregulation may affect the long-term health of mothers and their offspring. As such, miRNAs are potential candidates as biomarkers and therapeutic targets in diabetic pregnancies at risk of adverse outcomes.

Prospects and challenges of tissue-derived extracellular vesicles

Extracellular vesicles (EVs) are considered a vital component of cell-to-cell communication and represent a new frontier in diagnostics and a means to identify pathways for therapeutic intervention. Recently, studies have revealed the importance of tissue-derived EVs (Ti-EVs), which are EVs present in the interstitial spaces between cells, as they better represent the underlying physiology of complex, multicellular tissue microenvironments in biology and disease. EVs are native, lipid bilayer membraned nano-sized particles produced by all cells that are packaged with varied functional biomolecules including proteins, lipids, and nucleic acids. They are implicated in short- and long-range cellular communication and may elicit functional responses in recipient cells. To date, studies have often utilized cultured cells or biological fluids as a source for EVs that do not capture local molecular signatures of the tissue microenvironment. Recent work utilizing Ti-EVs has elucidated novel biomarkers for disease and provided insights into disease mechanisms that may lead to the development of novel therapeutic agents. Still, there are considerable challenges facing current studies. This review explores the vast potential and unique challenges for Ti-EV research and provides considerations for future studies that seek to advance this exciting field.

Adipose stem cells-derived small extracellular vesicles transport Thrombospondin 1 cargo to promote insulin resistance in gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) is a highly prevalent disease and poses a significant risk to the health of pregnant women. Abdominal adipose tissue (AT) contributes to insulin resistance (IR) associated with GDM. However, the underlying mechanisms remain unclear.

METHODS

In this study, we developed a mouse model of GDM by subjecting mice to a high-fat diet. We collected adipose-derived stem cells (ADSCs) from the abdominal and inguinal regions and examined their role in inducing IR in normal tissues through the secretion of small extracellular vesicles (sEVs). The sEVs derived from ADSCs isolated from GDM mice (ADSC/GDM) were found to inhibit cell viability and insulin sensitivity in AML12, a normal mouse liver cell line.

RESULTS

Through proteomic analysis, we identified high levels of the thrombospondin 1 (Thbs1) protein in the sEVs derived from ADSC/GDM. Subsequent overexpression of Thbs1 protein in AML12 cells demonstrated similar IR as observed with ADSC/GDM-derived sEVs. Mechanistically, the Thbs1 protein within the sEVs interacted with CD36 and transforming growth factor (Tgf) β receptors in AML12 cells, leading to the activation of Tgfβ/Smad2 signaling. Furthermore, the administration of LSKL, an antagonistic peptide targeting Thbs1, suppressed Thbs1 expression in ADSC/GDM-derived sEVs, thereby restoring insulin sensitivity in AML12 cells and GDM mice in vivo.

CONCLUSIONS

These findings shed light on the intercellular transmission mechanism through which ADSCs influence hepatic insulin sensitivity and underscore the therapeutic potential of targeting the Thbs1 protein within sEVs.

Early-Pregnancy Serum Maternal and Placenta-Derived Exosomes miRNAs Vary Based on Pancreatic β-Cell Function in GDM

CONTEXT

Pancreatic β-cell function impairment is a key mechanism for developing gestational diabetes mellitus (GDM). Maternal and placental exosomes regulate maternal and placental responses during hyperglycemia. Studies have associated exosomal micro-RNAs (miRNAs) with GDM development. To date, no studies have been reported that evaluate the profile of miRNAs present in maternal and placental exosomes in the early stages of gestation from pregnancies that develop GDM.

OBJECTIVE

We assessed whether early-pregnancy serum maternal and placenta-derived exosomes miRNA profiles vary according to pancreatic β-cell function in women who will develop GDM.

METHODS

A prospective nested case-control study was used to identify exosomal miRNAs that vary in early-pregnancy stages (<18 weeks of gestation) from women with normoglycemia and those who developed GDM based on their pancreatic β-cell function using the homeostasis model assessment of pancreatic β-cell function (HOMA-%β) index. Early-pregnancy serum maternal and placenta-derived exosomes were isolated to obtain miRNA profiles. Potential target and pathway analyses were performed to identify molecular and metabolic pathways associated with the exosomal miRNAs identified.

RESULTS

In early-pregnancy stages, serum maternal exosome size and concentration are modified in GDM group and fluctuate according to HOMA-%β index. Serum maternal exosomal hsa-miR-149-3p and hsa-miR-455-3p in GDM are related to insulin secretion and signaling, lipolysis, and adipocytokine signaling. Early-pregnancy serum placenta-derived exosomes hsa-miR-3665 and hsa-miR-6727-5p in GDM are related to regulating genes involved in response to immunological tolerance of pregnancy and pathways associated with placental dysfunction.

CONCLUSION

Early serum exosomal miRNAs differ depending on their origin (maternal or placental) and pancreatic β-cell function. This research provides insights into the interactions between maternal and placental exosomal miRNAs and may have implications for identifying potential biomarkers or therapeutic targets for GDM.

Research advances of tissue-derived extracellular vesicles in cancers

BACKGROUND

Extracellular vesicles (EVs) can mediate cell-to-cell communication and affect various physiological and pathological processes in both parent and recipient cells. Currently, extensive research has focused on the EVs derived from cell cultures and various body fluids. However, insufficient attention has been paid to the EVs derived from tissues. Tissue EVs can reflect the microenvironment of the specific tissue and the cross-talk of communication among different cells, which can provide more accurate and comprehensive information for understanding the development and progression of diseases.

METHODS

We review the state-of-the-art technologies involved in the isolation and purification of tissue EVs. Then, the latest research progress of tissue EVs in the mechanism of tumor occurrence and development is presented. And finally, the application of tissue EVs in the clinical diagnosis and treatment of cancer is anticipated.

RESULTS

We evaluate the strengths and weaknesses of various tissue processing and EVs isolation methods, and subsequently analyze the significance of protein characterization in determining the purity of tissue EVs. Furthermore, we focus on outlining the importance of EVs derived from tumor and adipose tissues in tumorigenesis and development, as well as their potential applications in early tumor diagnosis, prognosis, and treatment.

CONCLUSION

When isolating and characterizing tissue EVs, the most appropriate protocol needs to be specified based on the characteristics of different tissues. Tissue EVs are valuable in the diagnosis, prognosis, and treatment of tumors, and the potential risks associated with tissue EVs need to be considered as therapeutic agents.

3D bioprinted small extracellular vesicles from periodontal cells enhance mesenchymal stromal cell function

Recent research indicates that combining 3D bioprinting and small extracellular vesicles (sEVs) offers a promising 'cell-free' regenerative medicine approach for various tissue engineering applications. Nonetheless, the majority of existing research has focused on bioprinting of sEVs sourced from cell lines. There remains a notable gap in research regarding the bioprinting of sEVs derived from primary human periodontal cells and their potential impact on ligamentous and osteogenic differentiation. Here, we investigated the effect of 3D bioprinted periodontal cell sEVs constructs on the differentiation potential of human buccal fat pad-derived mesenchymal stromal cells (hBFP-MSCs). Periodontal cell-derived sEVs were enriched by size exclusion chromatography (SEC) with particle-shaped morphology, and characterized by being smaller than 200 nm in size and CD9/CD63/CD81 positive, from primary human periodontal ligament cells (hPDLCs) and human gingival fibroblasts (hGFs). The sEVs were then 3D bioprinted in 10 % gelatin methacryloyl (GelMA) via microextrusion bioprinting. Release of sEVs from bioprinted constructs was determined by DiO-labelling and confocal imaging, and CD9 ELISA. Attachment and ligament/osteogenic/cementogenic differentiation of hBFP-MSCs was assessed on bioprinted GelMA, without and with sEVs (GelMA/hPDLCs-sEVs and GelMA/hGFs-sEVs), scaffolds. hBFP-MSCs seeded on the bioprinted sEVs constructs spread well with significantly enhanced focal adhesion, mechanotransduction associated gene expression, and ligament and osteogenesis/cementogenesis differentiation markers in GelMA/hPDLCs-sEVs, compared to GelMA/hGFs-sEVs and GelMA groups. A 2-week osteogenic and ligamentous differentiation showed enhanced ALP staining, calcium formation and toluidine blue stained cells in hBFP-MSCs on bioprinted GelMA/hPDLCs-sEVs constructs compared to the other two groups. The proof-of-concept data from this study supports the notion that 3D bioprinted GelMA/hPDLCs-sEVs scaffolds promote cell attachment, as well as ligamentous, osteogenic and cementogenic differentiation, of hBFP-MSCs in vitro.

Human gestational diabetes mellitus-derived exosomes impair glucose homeostasis in pregnant mice and stimulate functional maturation of offspring-islets

AIMS

Pancreatic islets undergo critical development and functional maturation during the perinatal period when they are highly sensitive to microenvironment. We aim to determine the effects and mechanisms of gestational diabetes mellitus (GDM) hypermetabolic stress on glucose homeostasis in pregnant mice and functional maturation of the islets of their offspring.

MAIN METHODS

Exosomes were extracted from the umbilical vein blood of individuals with or without GDM for administration to pregnant mice. The blood glucose, serum insulin, glycosylated hemoglobin, and lipopolysaccharide levels were measured in pregnant mice. The expression and localization of insulin, glucagon, PC1/3, PDX1, and p-S6 in the islets of neonatal rats were continuously monitored using immunofluorescence to evaluate their functional status. Primary islet cells were cultured and treated with GDM exosomes and exendin to determine the expression of GLP-1R, AKT, p-AKT, and p-S6 via western blotting.

KEY FINDINGS

GDM exosomes induced remarkable oral glucose intolerance, hyperinsulinemia, and metabolic inflammation in pregnant mice. The islets of GDM offspring exhibited high insulin, glucagon, PC1/3, PDX1, and p-S6 expression at and after birth, and activation of the local GLP-1/GLP-1R axis. The functional maturation of normal-offspring islets did not commence until after birth, while it was activated prior to birth in GDM offspring, seriously disrupting the whole process. GDM exosomes activated the GLP-1/GLP-1R axis between α and β cells, and stimulated functional maturation of β cells via the Akt-mTORC1-pS6 pathway.

SIGNIFICANCE

These findings provide preliminary insights into the mechanisms underlying the high incidence of diabetes in the offspring of mothers with GDM.

Advances in extracellular vesicles as mediators of cell-to-cell communication in pregnancy

Cell-to-cell communication mediated by Extracellular Vesicles (EVs) is a novel and emerging area of research, especially during pregnancy, in which placenta derived EVs can facilitate the feto-maternal communication. EVs comprise a heterogeneous group of vesicle sub-populations with diverse physical and biochemical characteristics and originate by specific biogenesis mechanisms. EVs transfer molecular cargo (including proteins, nucleic acids, and lipids) between cells and are critical mediators of cell communication. There is growing interest among researchers to explore into the molecular cargo of EVs and their functions in a physiological and pathological context. For example, inflammatory mediators such as cytokines are shown to be released in EVs and EVs derived from immune cells play key roles in mediating the immune response as well as immunoregulatory pathways. Pregnancy complications such as gestational diabetes mellitus, preeclampsia, intrauterine growth restriction and preterm birth are associated with altered levels of circulating EVs, with differential EV cargo and bioactivity in target cells. This implicates the intriguing roles of EVs in reprogramming the maternal physiology during pregnancy. Moreover, the capacity of EVs to carry bioactive molecules makes them a promising tool for biomarker development and targeted therapies in pregnancy complications. This review summarizes the physiological and pathological roles played by EVs in pregnancy and pregnancy-related disorders and describes the potential of EVs to be translated into clinical applications in the diagnosis and treatment of pregnancy complications.

Recent progress in metabolic reprogramming in gestational diabetes mellitus: a review

Gestational diabetes mellitus is a prevalent metabolic disease that can impact the normal course of pregnancy and delivery, leading to adverse outcomes for both mother and child. Its pathogenesis is complex and involves various factors, such as insulin resistance and β-cell dysfunction. Metabolic reprogramming, which involves mitochondrial oxidative phosphorylation and glycolysis, is crucial for maintaining human metabolic balance and is involved in the pathogenesis and progression of gestational diabetes mellitus. However, research on the link and metabolic pathways between metabolic reprogramming and gestational diabetes mellitus is limited. Therefore, we reviewed the relationship between metabolic reprogramming and gestational diabetes mellitus to provide new therapeutic strategies for maternal health during pregnancy and reduce the risk of developing gestational diabetes mellitus.

Effects of periodontal cells-derived extracellular vesicles on mesenchymal stromal cell function

OBJECTIVE

To enrich and compare three extracellular vesicles-EV subtypes (apoptotic bodies, microvesicles and small EV) from three periodontal cells (periodontal ligament cells-PDLCs, alveolar bone-derived osteoblasts-OBs and gingival fibroblasts-GFs), and assess uptake and cell function changes in buccal fat pad-derived mesenchymal stromal cells (BFP-MSCs).

BACKGROUND

Periodontal cells such as PDLCs, OBs and GFs have the potential to enhance bone and periodontal regeneration, but face significant challenges, such as the regulatory and cost implications of in vitro cell culture and storage. To address these challenges, it is important to explore alternative 'cell-free' strategies, such as extracellular vesicles which have emerged as promising tools in regenerative medicine, to facilitate osteogenic differentiation and bone regeneration.

METHODS AND MATERIALS

Serial centrifuges at 2600 and 16 000 g were used to isolate apoptotic bodies and microvesicles respectively. Small EV-sEV was enriched by our in-house size exclusion chromatography (SEC). The cellular uptake, proliferation, migration and osteogenic/adipogenic differentiation genes were analysed after EVs uptake in BFP-MSCs.

RESULTS

Three EV subtypes were enriched and characterised by morphology, particle size and EV-associated protein expression-CD9. Cellular uptake of the three EVs subtypes was observed in BFP-MSCs for up to 7 days. sEV from the three periodontal cells promoted proliferation, migration and osteogenic gene expression. hOBs-sEV showed superior levels of osteogenesis markers compared to that hPDLCs-sEV and hGFs-sEV, while hOBs-16k EV promoted adipogenic gene expression compared to that from hPDLCs and hGFs.

CONCLUSIONS

Our proof-of-concept data demonstrate that hOBs-sEV might be an alternative cell-free therapeutic for bone tissue engineering.

Glycolysis: A fork in the path of normal and pathological pregnancy

Glucose metabolism is vital to the survival of living organisms. Since the discovery of the Warburg effect in the 1920s, glycolysis has become a major research area in the field of metabolism. Glycolysis has been extensively studied in the field of cancer and is considered as a promising therapeutic target. However, research on the role of glycolysis in pregnancy is limited. Recent evidence suggests that blastocysts, trophoblasts, decidua, and tumors all acquire metabolic energy at specific stages in a highly similar manner. Glycolysis, carefully controlled throughout pregnancy, maintains a dynamic and coordinated state, so as to maintain the homeostasis of the maternal-fetal interface and ensure normal gestation. In the present review, we investigate metabolic remodeling and the selective propensity of the embryo and placenta for glycolysis. We then address dysregulated glycolysis that occurs in the cellular interactive network at the maternal-fetal interface in miscarriage, preeclampsia, fetal growth restriction, and gestational diabetes mellitus. We provide new insights into the field of maternal-fetal medicine from a metabolic perspective, thus revealing the mystery of human pregnancy.

Extracellular vesicles as markers and mediators of pregnancy complications: gestational diabetes, pre-eclampsia, preterm birth and fetal growth restriction

In high income countries, approximately 10% of pregnancies are complicated by pre-eclampsia (PE), preterm birth (PTB), fetal growth restriction (FGR) and/or macrosomia resulting from gestational diabetes (GDM). Despite the burden of disease this places on pregnant people and their newborns, there are still few, if any, effective ways of preventing or treating these conditions. There are also gaps in our understanding of the underlying pathophysiologies and our ability to predict which mothers will be affected. The placenta plays a crucial role in pregnancy, and alterations in placental structure and function have been implicated in all of these conditions. As extracellular vesicles (EVs) have emerged as important molecules in cell-to-cell communication in health and disease, recent research involving maternal- and placental-derived EV has demonstrated their potential as predictive and diagnostic biomarkers of obstetric disorders.  This review will consider how placental and maternal EVs have been investigated in pregnancies complicated by PE, PTB, FGR and GDM and aims to highlight areas where further research is required to enhance the management and eventual treatment of these pathologies.

Comparative Analysis of Protein Digestion Characteristics in Human, Cow, Goat, Sheep, Mare, and Camel Milk under Simulated Infant Condition

An infant in vitro digestion model was utilized to investigate protein digestion characteristics in human and diverse mammalian milk (i.e., cow, goat, sheep, mare, and camel milk) using electrophoresis and chromatography. Digestive differences among milks were mainly manifested in the infant gastric phase, as evidenced by varying degrees of protein digestion. Notably, proteins (i.e., lactoferrin, serum albumin, and immunoglobulin G-heavy chain) remained partially intact in human milk, whereas these proteins in animal milk were exclusively degraded after gastrointestinal digestion. The peptide spectra of human, mare, and camel milk were highly similar, with a predominant formation of low-intensity small peptides, whereas the other three milk showed the opposite phenomenon. Heatmap cluster analysis indicated that camel milk was the most comparable to human milk before digestion, yet sheep milk was the most similar to human milk regarding protein digestion behaviors following infant gastric digestion.

Extracellular vesicle-mediated targeting strategies for long-term health benefits in gestational diabetes

Extracellular vesicles (EVs) are critical mediators of cell communication, playing important roles in regulating molecular cross-talk between different metabolic tissues and influencing insulin sensitivity in both healthy and gestational diabetes mellitus (GDM) pregnancies. The ability of EVs to transfer molecular cargo between cells imbues them with potential as therapeutic agents. During pregnancy, the placenta assumes a vital role in metabolic regulation, with multiple mechanisms of placenta-mediated EV cross-talk serving as central components in GDM pathophysiology. This review focuses on the role of the placenta in the pathophysiology of GDM and explores the possibilities and prospects of targeting the placenta to address insulin resistance and placental dysfunction in GDM. Additionally, we propose the use of EVs as a novel method for targeted therapeutics in treating the dysfunctional placenta. The primary aim of this review is to comprehend the current status of EV targeting approaches and assess the potential application of these strategies in placental therapeutics, thereby delivering molecular cargo and improving maternal and fetal outcomes in GDM. We propose that EVs have the potential to revolutionize GDM management, offering hope for enhanced maternal-fetal health outcomes and more effective treatments.

Adipocyte-Derived Exosomal NOX4-Mediated Oxidative Damage Induces Premature Placental Senescence in Obese Pregnancy

Background

A recent study has reported that maternal obesity is linked to placental oxidative damage and premature senescence. NADPH oxidase 4 (NOX4) is massively expressed in adipose tissue, and its induced reactive oxygen species have been found to contribute to cellular senescence. While, whether, in obese pregnancy, adipose tissue-derived NOX4 is the considerable cause of placental senescence remained elusive.

Methods

This study collected term placentas from obese and normal pregnancies and obese pregnant mouse model was constructed by a high fat diet to explore placental senescence. Furthermore, adipocyte-derived exosomes were isolated from primary adipocyte medium of obese and normal pregnancies to examine their effect on placenta functions in vivo and vitro.

Results

The placenta from the obese group showed a significant increase in placental oxidative damage and senescence. Exosomes from obese adipocytes contained copies of NOX4, and when cocultured with HTR8/SVneo cells, they induced severe oxidative damage, cellular senescence, and suppressed proliferation and invasion functions when compared with the control group. In vivo, adipocyte-derived NOX4-containing exosomes could induce placental oxidative damage and senescence, ultimately leading to adverse pregnancy outcomes.

Conclusion

In obesity, adipose tissue can secrete exosomes containing NOX4 which can be delivered to trophoblast resulting in severe DNA oxidative damage and premature placental senescence, ultimately leading to adverse pregnancy outcomes.

Exosomal non coding RNAs as a novel target for diabetes mellitus and its complications

Diabetes mellitus (DM) is a first-line priority among the problems facing medical science and public health in almost all countries of the world. The main problem of DM is the high incidence of damage to the cardiovascular system, which in turn leads to diseases such as myocardial infarction, stroke, gangrene of the lower extremities, blindness and chronic renal failure. As a result, the study of the molecular genetic mechanisms of the pathogenesis of DM is of critical importance for the development of new diagnostic and therapeutic strategies. Molecular genetic aspects of the etiology and pathogenesis of diabetes mellitus are intensively studied in well-known laboratories around the world. One of the strategies in this direction is to study the role of exosomes in the pathogenesis of DM. Exosomes are microscopic extracellular vesicles with a diameter of 30-100 nm, released into the intercellular space by cells of various tissues and organs. The content of exosomes depends on the cell type and includes mRNA, non-coding RNAs, DNA, and so on. Non-coding RNAs, a group of RNAs with limited transcriptional activity, have been discovered to play a significant role in regulating gene expression through epigenetic and posttranscriptional modulation, such as silencing of messenger RNA. One of the problems of usage exosomes in DM is the identification of the cellular origin of exosomes and the standardization of protocols for molecular genetic studies in clinical laboratories. In addition, the question of the target orientation of exosomes and their targeted activity requires additional study. Solving these and other problems will make it possible to use exosomes for the diagnosis and delivery of drugs directly to target cells in DM. This study presents an analysis of literature data on the role of exosomes and ncRNAs in the development and progression of DM, as well as the prospects for the use of exosomes in clinical practice in this disease.

Extracellular Vesicles as Carriers of Adipokines and Their Role in Obesity

Extracellular vesicles (EVs) have lately arisen as new metabolic players in energy homeostasis participating in intercellular communication at the local and distant levels. These nanosized lipid bilayer spheres, carrying bioactive molecular cargo, have somehow changed the paradigm of biomedical research not only as a non-classic cell secretion mechanism, but as a rich source of biomarkers and as useful drug-delivery vehicles. Although the research about the role of EVs on metabolism and its deregulation on obesity and associated pathologies lagged slightly behind other diseases, the knowledge about their function under normal and pathological homeostasis is rapidly increasing. In this review, we are focusing on the current research regarding adipose tissue shed extracellular vesicles including their characterization, size profile, and molecular cargo content comprising miRNAs and membrane and intra-vesicular proteins. Finally, we will focus on the functional aspects attributed to vesicles secreted not only by adipocytes, but also by other cells comprising adipose tissue, describing the evidence to date on the deleterious effects of extracellular vesicles released by obese adipose tissue both locally and at the distant level by interacting with other peripheral organs and even at the central level.

Prospecting of exosomal-miRNA signatures as prognostic marker for gestational diabetes mellitus and other adverse pregnancy outcomes

Exosomal microRNA (ExomiRs) serves as potential cargo molecules responsible for post-translation of gene expression and intracellular communication playing a vital role in acting as clinically relevant prognostic biomarkers for identifying pregnancy-associated complications in patients. ExomiRs are associated with Gestational Diabetes Mellitus (GDM) as potential targets for understanding the pathophysiology of beta-cell dysfunction. ExomiRs (ExomiR 122, ExomiR 16-5p, ExomiR 215-5p, ExomiR 450b-3p, ExomiR 122-5p) aid to act as biomarkers and regulate the progression of diabetes and its related complication. These ExomiRshave been reported to interfere with the regulation of various genes such as ZEB2, IRS1, IRS2, GLUT1, GLUT4, etc. and inhibition of several pathways like PI3K/AKT, Wnt, and mTOR signaling pathways leading to the modulation in the development of GDM affecting the clinical and pathological features of women. These ExomiRs have also been associated with other pregnancy-associated complications, including preeclampsia, hypothyroidism, pregnancy loss, and ectopic pregnancies. On the other hand, overexpression of certain ExomiRs such as Exomir-515-5p, ExomiR-221, and ExomiR-96 serve a regulatory role in overcoming insulin resistance. Taken together, the current review focuses on the prospective capabilities of ExomiRs for diagnosis and clinical prognosis of GDM women with respect to pregnancy outcomes.

Research advances and challenges in tissue-derived extracellular vesicles

Extracellular vesicles (EV) are vesicular vesicles with phospholipid bilayer, which are present in biological fluids and extracellular microenvironment. Extracellular vesicles serve as pivotal mediators in intercellular communication by delivering lipids, proteins, and RNAs to the recipient cells. Different from extracellular vesicles derived from biofluids and that originate from cell culture, the tissue derived extracellular vesicles (Ti-EVs) send us more enriched and accurate information of tissue microenvironment. Notably, tissue derived extracellular vesicles directly participate in the crosstalk between numerous cell types within microenvironment. Current research mainly focused on the extracellular vesicles present in biological fluids and cell culture supernatant, yet the studies on tissue derived extracellular vesicles are increasing due to the tissue derived extracellular vesicles are promising agents to reflect the occurrence and development of human diseases more accurately. In this review, we aimed to clarify the characteristics of tissue derived extracellular vesicles, specify the isolation methods and the roles of tissue derived extracellular vesicles in various diseases, including tumors. Moreover, we summarized the advances and challenges of tissue derived extracellular vesicles research.

Unfolding the role of placental-derived Extracellular Vesicles in Pregnancy: From homeostasis to pathophysiology

The human placenta is a critical structure with multiple roles in pregnancy, including fetal nutrition and support, immunological, mechanical and chemical barrier as well as an endocrine activity. Besides, a growing body of evidence highlight the relevance of this organ on the maternofetal wellbeing not only during gestation, but also from birth onwards. Extracellular vesicles (EVs) are complex macromolecular structures of different size and content, acting as carriers of a diverse set of molecules and information from donor to recipient cells. Since its early development, the production and function of placental-derived EVs are essential to ensure an adequate progress of pregnancy. In turn, the fetus receives and produce their own EVs, highlighting the importance of these components in the maternofetal communication. Moreover, several studies have shown the clinical relevance of EVs in different obstetric pathologies such as preeclampsia, infectious diseases or gestational diabetes, among others, suggesting that they could be used as pathophysiological biomarkers of these diseases. Overall, the aim of this article is to present an updated review of the published basic and translational knowledge focusing on the role of placental-derived EVs in normal and pathological pregnancies. We suggest as well future lines of research to take in this novel and promising field.

Parental obesity-induced changes in developmental programming

Many studies support the link between parental obesity and the predisposition to develop adult-onset metabolic syndromes that include obesity, high blood pressure, dyslipidemia, insulin resistance, and diabetes in the offspring. As the prevalence of obesity increases in persons of childbearing age, so does metabolic syndrome in their descendants. Understanding how parental obesity alters metabolic programs in the progeny, predisposing them to adult-onset metabolic syndrome, is key to breaking this cycle. This review explores the basis for altered metabolism of offspring exposed to overnutrition by focusing on critical developmental processes influenced by parental obesity. We draw from human and animal model studies, highlighting the adaptations in metabolism that occur during normal pregnancy that become maladaptive with obesity. We describe essential phases of development impacted by parental obesity that contribute to long-term alterations in metabolism in the offspring. These encompass gamete formation, placentation, adipogenesis, pancreas development, and development of brain appetite control circuits. Parental obesity alters the developmental programming of these organs in part by inducing epigenetic changes with long-term consequences on metabolism. While exposure to parental obesity during any of these phases is sufficient to alter long-term metabolism, offspring often experience multiple exposures throughout their development. These insults accumulate to increase further the susceptibility of the offspring to the obesogenic environments of modern society.

Proteomic Approaches in the Study of Placenta of Pregnancy Complicated by Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM), a glucose intolerance developing or first recognized during pregnancy, leads to a series of short- and long-term maternal and fetal complications, somehow related to placenta structural and functional changes. The focus and the objective of the present review are to discuss the results which can be obtained by different mass spectrometric approaches in the study of placenta protein profile. Thus, matrix-assisted laser desorption/ionization mass spectrometry (MALDI) has been applied on placenta omogenates before and after one-dimensional electrophoretic separation, followed by tryptic digestion. MALDI imaging was used for direct investigation on the placenta tissue (both maternal and fetal sides). The results showed that some differences among the absolute abundances of some proteins are present for placenta samples from GDM patients. The majority of investigations were carried out by two-dimensional electrophoresis (2DE) followed by LC-MS/MS or, directly by the label-free LC-MS^E approach. It should be emphasized that all these techniques were showed differences in the protein expression between the placenta samples from healthy or GDM subjects. 2DE was also employed to separate and compare placental protein levels from GDM and the control groups: differentially expressed proteins between the two groups were identified by MALDI-TOF/TOF mass spectrometry and were further confirmed by Western blotting. The physiopathological significance of the obtained results are reported and discussed in this narrative review. The experimental data obtained until now show that the newest, mass spectrometric approaches can be considered a valid tool to investigate the possible changes of placenta in the presence of GDM.

Composition of Maternal Circulating Short-Chain Fatty Acids in Gestational Diabetes Mellitus and Their Associations with Placental Metabolism

Short-chain fatty acids (SCFAs), which are produced by gut microbiota from dietary fiber, have become candidates for gestational diabetes mellitus (GDM) treatment. However, the associations of circulating SCFAs with maternal-neonatal clinical parameters in GDM and further influences on placental immune-metabolic responses are unclear. Acetate, propionate, and butyrate were decreased in GDM during the second and third trimesters, especially in those with abnormal glucose tolerance at three "oral glucose tolerance test" time points. Butyrate was closely associated with acetate and propionate in correlation and dynamic trajectory analysis. Moreover, butyrate was negatively correlated with white blood cell counts, neutrophil counts, prepregnancy BMI, gestational weight gain per week before GDM diagnosis, and ponderal index but positively correlated with total cholesterol and low-density lipoprotein levels in all pregnancies. On the premise of reduced SCFA contents in GDM, the placental G-protein-coupled receptors 41 and 43 (GPR41/43) were decreased, and histone deacetylases (HDACs) were increased, accompanied by enhanced inflammatory responses. The metabolic status was disturbed, as evidenced by activated glycolysis in GDM. Maternal circulating acetate, propionate, and butyrate levels were associated with demographic factors in normal and GDM women. They influenced placental function and fetal development at birth through GPRs or HDACs, providing more evidence of their therapeutic capacity for GDM pregnancies.

The link between gestational diabetes and cardiovascular diseases: potential role of extracellular vesicles

Extracellular vesicles are critical mediators of cell communication. They encapsulate a variety of molecular cargo such as proteins, lipids, and nucleic acids including miRNAs, lncRNAs, circular RNAs, and mRNAs, and through transfer of these molecular signals can alter the metabolic phenotype in recipient cells. Emerging studies show the important role of extracellular vesicle signaling in the development and progression of cardiovascular diseases and associated risk factors such as type 2 diabetes and obesity. Gestational diabetes mellitus (GDM) is hyperglycemia that develops during pregnancy and increases the future risk of developing obesity, impaired glucose metabolism, and cardiovascular disease in both the mother and infant. Available evidence shows that changes in maternal metabolism and exposure to the hyperglycemic intrauterine environment can reprogram the fetal genome, leaving metabolic imprints that define life-long health and disease susceptibility. Understanding the factors that contribute to the increased susceptibility to metabolic disorders of children born to GDM mothers is critical for implementation of preventive strategies in GDM. In this review, we discuss the current literature on the fetal programming of cardiovascular diseases in GDM and the impact of extracellular vesicle (EV) signaling in epigenetic programming in cardiovascular disease, to determine the potential link between EV signaling in GDM and the development of cardiovascular disease in infants.

Hyperglycemia in Pregnancy-Associated Oxidative Stress Augments Altered Placental Glucose Transporter 1 Trafficking via AMPKα/p38MAPK Signaling Cascade

GLUT1, being a ubiquitous transporter isoform, is considered primarily responsible for glucose uptake during glycolysis. However, there is still uncertainty about the regulatory mechanisms of GLUT1 in hyperglycemia in pregnancy (HIP, PGDM, and GDM) accompanied by abnormal oxidative stress responses. In the present study, it was observed that the glycolysis was enhanced in GDM and PGDM pregnancies. In line with this, the antioxidant system was disturbed and GLUT1 expression was increased due to diabetes impairment in both placental tissues and in vitro BeWo cells. GLUT1 responded to high glucose stimulation through p38MAPK in an AMPKα-dependent manner. Both the medical-mediated and genetic depletion of p38MAPK in BeWo cells could suppress GLUT1 expression and OS-induced proapoptotic effects. Furthermore, blocking AMPKα with an inhibitor or siRNA strategy promoted p38MAPK, GLUT1, and proapoptotic molecules expression and vice versa. In general, a new GLUT1 regulation pathway was identified, which could exert effects on placental transport function through the AMPKα-p38MAPK pathway. AMPKα may be a therapeutic target in HIP for alleviating diabetes insults.

Exosomes and exosomal non‑coding RNAs throughout human gestation (Review)

In recent years, research on exosomes and their content has been intensive, which has revealed their important role in cell-to-cell communication, and has implicated exosomal biomolecules in a broad spectrum of physiological processes, as well as in the pathogenesis of various diseases. Pregnancy and its normal progression rely highly on the efficient communication between the mother and the fetus, mainly mediated by the placenta. Recent studies have established the placenta as an important source of circulating exosomes and have demonstrated that exosome release into the maternal circulation gradually increases during pregnancy, starting from six weeks of gestation. This orchestrates maternal-fetal crosstalk, including maternal immune tolerance and pregnancy-associated metabolic adaptations. Furthermore, an increased number of secreted exosomes, along with altered patterns of exosomal non-coding RNAs (ncRNAs), especially microRNAs and long non-coding RNAs (lncRNAs), have been observed in a number of pregnancy complications, such as gestational diabetes mellitus and preeclampsia. The early detection of exosomes and specific exosomal ncRNAs in various biological fluids during pregnancy highlights them as promising candidate biomarkers for the diagnosis, prognosis and treatment of numerous pregnancy disorders in adolescents and adults. The present review aimed to provide insight into the current knowledge regarding the potential, only partially elucidated, role of exosomes and exosomal cargo in the regulation and progression of normal pregnancy, as well as their potential dysregulation and contribution to pathological pregnancy situations.

The Mystery of Exosomes in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is one of the common pregnancy complications, which increases the risk of short-term and long-term adverse consequences in both the mother and offspring. However, the pathophysiological mechanism of GDM is still poorly understood. Inflammation, insulin resistance and oxidative stress are considered critical factors in the occurrence and development of GDM. Although the lifestyle intervention and insulin are the primary treatment, adverse pregnancy outcomes still cannot be ignored. Exosomes have a specific function of carrying biological information, which can transmit information to target cells and play an essential role in intercellular communication. Their possible roles in normal pregnancy and GDM have been widely concerned. The possibility of exosomal cargos as biomarkers of GDM is proposed. This paper reviews the literature in recent years and discusses the role of exosomes in GDM and their possible mechanisms to provide some reference for the prediction, prevention, and treatment of GDM and improve the outcome of pregnancy.

The role of extracellular vesicles in animal reproduction and diseases

Extracellular vesicles (EVs) are nanosized membrane-enclosed compartments that serve as messengers in cell-to-cell communication, both in normal physiology and in pathological conditions. EVs can transfer functional proteins and genetic information to alter the phenotype and function of recipient cells, which undergo different changes that positively affect their structural and functional integrity. Biological fluids are enriched with several subpopulations of EVs, including exosomes, microvesicles (MVs), and apoptotic bodies carrying several cargoes, such as lipids, proteins, and nucleic acids. EVs associated with the reproductive system are actively involved in the regulation of different physiological events, including gamete maturation, fertilization, and embryo and fetal development. EVs can influence follicle development, oocyte maturation, embryo production, and endometrial-conceptus communication. EVs loaded with cargoes are used to diagnose various diseases, including pregnancy disorders; however, these are dependent on the type of cell of origin and pathological characteristics. EV-derived microRNAs (miRNAs) and proteins in the placenta regulate inflammatory responses and trophoblast invasion through intercellular delivery in the placental microenvironment. This review presents evidence regarding the types of extracellular vesicles, and general aspects of isolation, purification, and characterization of EVs, particularly from various types of embryos. Further, we discuss EVs as mediators and messengers in reproductive biology, the effects of EVs on placentation and pregnancy disorders, the role of EVs in animal reproduction, in the male reproductive system, and mother and embryo cross-communication. In addition, we emphasize the role of microRNAs in embryo implantation and the role of EVs in reproductive and therapeutic medicine. Finally, we discuss the future perspectives of EVs in reproductive biology.

Extracellular Vesicles and Their Emerging Roles as Cellular Messengers in Endocrinology: An Endocrine Society Scientific Statement

During the last decade, there has been great interest in elucidating the biological role of extracellular vesicles (EVs), particularly, their hormone-like role in cell-to-cell communication. The field of endocrinology is uniquely placed to provide insight into the functions of EVs, which are secreted from all cells into biological fluids and carry endocrine signals to engage in paracellular and distal interactions. EVs are a heterogeneous population of membrane-bound vesicles of varying size, content, and bioactivity. EVs are specifically packaged with signaling molecules, including lipids, proteins, and nucleic acids, and are released via exocytosis into biofluid compartments. EVs regulate the activity of both proximal and distal target cells, including translational activity, metabolism, growth, and development. As such, EVs signaling represents an integral pathway mediating intercellular communication. Moreover, as the content of EVs is cell-type specific, it is a "fingerprint" of the releasing cell and its metabolic status. Recently, changes in the profile of EV and bioactivity have been described in several endocrine-related conditions including diabetes, obesity, cardiovascular diseases, and cancer. The goal of this statement is to highlight relevant aspects of EV research and their potential role in the field of endocrinology.

The implications of exosomes in pregnancy: emerging as new diagnostic markers and therapeutics targets

Extracellular vehicles (EVs) are a heterogeneous group of cell and membranous particles originating from different cell compartments. EVs participate in many essential physiological functions and mediate fetal-maternal communications. Exosomes are the smallest unit of EVs, which are delivered to the extracellular space. Exosomes can be released by the umbilical cord, placenta, amniotic fluid, and amniotic membranes and are involved in angiogenesis, endothelial cell migration, and embryo implantation. Also, various diseases such as gestational hypertension, gestational diabetes mellitus (GDM), preterm birth, and fetal growth restriction can be related to the content of placental exosomes during pregnancy. Due to exosomes' ability to transport signaling molecules and their effect on sperm function, they can also play a role in male and female infertility. In the new insight, exosomal miRNA can diagnose and treat infertilities disorders. In this review, we focused on the functions of exosomes during pregnancy. Video abstract.

Extracellular vesicles in gestational diabetes mellitus: A scoping review

Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy worldwide. Despite extensive study, the molecular mechanisms leading to GDM and associated perinatal complications are not well understood. The condition is also associated with an increased risk of future cardiometabolic disease in both mothers and their offspring. Thus, there is a pressing need for the development of effective screening tools and to identify novel molecular mechanisms responsible for the short and long-term risks associated with GDM. In this regard, extracellular vesicles (EVs) offer promise as novel biomarkers of GDM-mediated changes to both mother and fetus. The purpose of this scoping review is to provide an overview of studies examining EVs in the context of GDM. EMBASE and Ovid Medline were searched for articles published from inception to December 2020. We update current knowledge in this area and identify key knowledge gaps with recommendations for future research.

Tissue-derived extracellular vesicles in cancers and non-cancer diseases: Present and future

Extracellular vesicles (EVs) are lipid‐bilayer membrane structures secreted by most cell types. EVs act as messengers via the horizontal transfer of lipids, proteins, and nucleic acids, and influence various pathophysiological processes in both parent and recipient cells. Compared to EVs obtained from body fluids or cell culture supernatants, EVs isolated directly from tissues possess a number of advantages, including tissue specificity, accurate reflection of tissue microenvironment, etc., thus, attention should be paid to tissue‐derived EVs (Ti‐EVs). Ti‐EVs are present in the interstitium of tissues and play pivotal roles in intercellular communication. Moreover, Ti‐EVs provide an excellent snapshot of interactions among various cell types with a common histological background. Thus, Ti‐EVs may be used to gain insights into the development and progression of diseases. To date, extensive investigations have focused on the role of body fluid‐derived EVs or cell culture‐derived EVs; however, the number of studies on Ti‐EVs remains insufficient. Herein, we summarize the latest advances in Ti‐EVs for cancers and non‐cancer diseases. We propose the future application of Ti‐EVs in basic research and clinical practice. Workflows for Ti‐EV isolation and characterization between cancers and non‐cancer diseases are reviewed and compared. Moreover, we discuss current issues associated with Ti‐EVs and provide potential directions.

Composition, isolation, identification and function of adipose tissue-derived exosomes

Exosomes are nano-sized extracellular vesicles (30–160 nm diameter) with lipid bilayer membrane secrete by various cells that mediate the communication between cells and tissue, which contain a variety of non-coding RNAs, mRNAs, proteins, lipids and other functional substances. Adipose tissue is important energy storage and endocrine organ in the organism. Recent studies have revealed that adipose tissue-derived exosomes (AT-Exosomes) play a critical role in many physiologically and pathologically functions. Physiologically, AT-Exosomes could regulate the metabolic homoeostasis of various organs or cells including liver and skeletal muscle. Pathologically, they could be used in the treatment of disease and or that they may be involved in the progression of the disease. In this review, we describe the basic principles and methods of exosomes isolation and identification, as well as further summary the specific methods. Moreover, we categorize the relevant studies of AT-Exosomes and summarize the different components and biological functions of mammalian exosomes. Most importantly, we elaborate AT-Exosomes crosstalk within adipose tissue and their functions on other tissues or organs from the physiological and pathological perspective. Based on the above analysis, we discuss what remains to be discovered problems in AT-Exosomes studies and prospect their directions needed to be further explored in the future.

Digestibility of proteins in camel milk in comparison to bovine and human milk using an in vitro infant gastrointestinal digestion system

The absence of β-lactoglobulin, high β-/α_s-casein ratio and protective proteins make camel milk a promising alternative protein base for making human infant formulae. In this study, protein digestibility of camel milk was compared with that of bovine and human milk using an in vitro infant gastrointestinal digestion system. A low degree of gastric proteolysis was observed in all three kinds of milk, and a single clot was formed in camel milk. The soluble milk proteins remaining in the gastric digesta were digested rapidly and extensively in the intestinal phase, while the proteins in the camel milk clot were hydrolysed gradually. Despite several similarities, bioactive peptides unique to individual milk were identified in the three intestinal milk digesta. The results suggest that camel milk proteins are equally digestible as bovine and human milk proteins under infant gastrointestinal digestion conditions, and it may be a prospective substitute for infant formula base.

Early markers of gestational diabetes mellitus: what we know and which way forward?

Women's metabolism during pregnancy undergoes numerous changes that can lead to gestational diabetes mellitus (GDM). The cause and pathogenesis of GDM, a heterogeneous disease, are not completely clear, but GDM is increasing in prevalence and is associated with the modern lifestyle. Most diagnoses of GDM are made via the guidelines from the International Association of Diabetes and Pregnancy Study Groups (IADSPG), which involve an oral glucose tolerance test (OGTT) between 24 and 28 weeks of pregnancy. Diagnosis in this stage of pregnancy can lead to short- and long-term implications for the mother and child. Therefore, there is an urgent need for earlier GDM markers in order to enable prevention and earlier treatment. Routine GDM biomarkers (plasma glucose, insulin, C-peptide, homeostatic model assessment of insulin resistance, and sex hormone-binding globulin) can differentiate between healthy pregnant women and those with GDM but are not suitable for early GDM diagnosis. In this article, we present an overview of the potential early biomarkers for GDM that have been investigated recently. We also present our view of future developments in the laboratory diagnosis of GDM.

Tissue-derived extracellular vesicles: Research progress from isolation to application

Extracellular vesicles (EVs) are the structures that all cells release into the environment. They are separated by a lipid bilayer and contain the cellular components that release them. To date, most studies have been performed on EVs derived from cell supernatants or different body fluids, while the number of studies on EV isolation directly from tissues is still limited. Studies of EV isolation directly from tissues may provide us with better information. This review summarizes the role of EV in the extracellular matrix, the protocol for isolation of EV in the tissue interstitium, and the application of the protocol in different tissues.

Exosomal mRNA and lncRNA profiles in cord blood of preeclampsia patients

BACKGROUND

Exosomes are endosome-derived membrane vesicles that contain numerous RNAs and allow intercellular communication. The roles of mRNAs and lncRNAs from umbilical cord blood exosomes in the development of preeclampsia (PE) remain unclear.

METHODS

In the study, microarray technology was used to construct the differential mRNA and lncRNA expression profiles in umbilical cord blood exosomes between PE patients and normal controls.

RESULTS

Totally, 120 differentially expressed mRNAs and 248 differentially expressed lncRNAs were identified. Pathway analysis showed that the differentially expressed mRNAs were related to glycolysis/gluconeogenesis, PI3K-Akt signaling pathway and JAK-STAT signaling pathway, which are critical in PE development. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were conducted for the differential lncRNA-associated mRNAs. We found several significantly enriched pathways were closely associated with metabolic process, cell proliferation, differentiation, and apoptosis. Moreover, the constructed pathway network revealed key pathways in PE, including apoptosis and TGF-beta signaling pathway. Further analysis of lncRNA/miRNA interactions showed that most of the lncRNAs had miRNA binding sites, and some of them were associated with PE.

CONCLUSIONS

The study highlights the importance of exosomal mRNAs and lncRNAs in umbilical cord blood, and provides new insight into the development of PE.

Epigenetic Changes in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is defined as carbohydrate intolerance that appears or is for the first time diagnosed during pregnancy. It can lead to many complications in the mother and in the offspring, so diagnostics and management of GDM are important to avoid adverse pregnancy outcomes. Epigenetic studies revealed the different methylation status of genes in pregnancies with GDM compared to pregnancies without GDM. A growing body of evidence shows that the GDM can affect not only the course of the pregnancy, but also the development of the offspring, thus contributing to long-term effects and adverse health outcomes of the progeny. Epigenetic changes occur through histone modification, DNA methylation, and disrupted function of non-coding ribonucleic acid (ncRNA) including microRNAs (miRNAs). In this review, we focus on the recent knowledge about epigenetic changes in GDM. The analysis of this topic may help us to understand pathophysiological mechanisms in GDM and find a solution to prevent their consequences.

Impact of exosome-mediated feto-maternal interactions on pregnancy maintenance and development of obstetric complications

Pregnancy is an immunological paradox, a phenomenon in which the foetus and the placenta, containing foreign antigens to the mother, develop without inducing rejection by the maternal immune system. Cell-to-cell communication between the foetus and the mother is mediated by secreted factors such as cytokines, hormones and extracellular vesicles (EVs) for a successful pregnancy and to avoid rejection. Exosomes, the smallest of EVs, are released extracellularly, where they are taken up by proximal or distant recipient cells. Here, we discuss the role of EVs, especially exosomes in feto-maternal communication during pregnancy. This review will provide an overview of the functional roles exosomes may play during embryo implantation, modulating immune responses during pregnancy and the onset of labour. Moreover, we will discuss exosomal function in obstetric pathology, and the development of pregnancy-associated complications such as preeclampsia and preterm birth as well as the biomarker potential of exosomes for detecting such conditions.

Role of Extracellular Vesicles in Placental Inflammation and Local Immune Balance

Background

Pregnancy maintenance depends on the formation of normal placentas accompanied by trophoblast invasion and vascular remodeling. Various types of cells, such as trophoblasts, endothelial cells, immune cells, mesenchymal stem cells (MSCs), and adipocytes, mediate cell-to-cell interactions through soluble factors to maintain normal placental development. Extracellular vesicles (EVs) are diverse nanosized to microsized membrane-bound particles released from various cells. EVs contain tens to thousands of different RNA, proteins, small molecules, DNA fragments, and bioactive lipids. EV-derived microRNAs (miRNAs) and proteins regulate inflammation and trophoblast invasion in the placental microenvironment. Maternal-fetal communication through EV can regulate the key signaling pathways involved in pregnancy maintenance, from implantation to immune regulation. Therefore, EVs and the encapsulating factors play important roles in pregnancy, some of which might be potential biomarkers.

Conclusion

In this review, we have summarized published studies about the EVs in the placentation and pregnancy-related diseases. By summarizing the role of EVs and their delivering active molecules in pregnancy-related diseases, it provides novel insight into the diagnosis and treatment of diseases.

Adipose tissue function in healthy pregnancy, gestational diabetes mellitus and pre-eclampsia

Gestational diabetes mellitus (GDM) is a common disorder of pregnancy with short- and long-term consequences for mother and baby. Pre-eclampsia is of major concern to obstetricians due to its sudden onset and increased morbidity and mortality for mother and baby. The incidence of these conditions continues to increase due to widespread maternal obesity. Maternal obesity is a risk factor for GDM and pre-eclampsia, yet our understanding of the role of adipose tissue and adipocyte biology in their aetiology is very limited. In this article, available data on adipose tissue and adipocyte function in healthy and obese pregnancy and how these are altered in GDM and pre-eclampsia are reviewed. Using our understanding of adipose tissue and adipocyte biology in non-pregnant populations, a role for underlying adipocyte dysfunction in the pathological pathways of these conditions is discussed.

Placenta-Derived Exosomes as a Modulator in Maternal Immune Tolerance During Pregnancy

Exosomes are a subset of extracellular vesicles with an average diameter of ~100nm. Exosomes are released by all cells through an endosome-dependent pathway and carry nucleic acids, proteins, lipids, cytokines and metabolites, mirroring the state of the originating cells. The function of exosomes has been implicated in various reproduction processes, such as embryo development, implantation, decidualization and placentation. Placenta-derived exosomes (pEXO) can be detected in the maternal blood as early as 6 weeks after conception and their levels increase with gestational age. Importantly, alternations in the molecular signatures of pEXO are observed in pregnancy-related complications. Thus, these differentially expressed molecules could be the potential biomarkers for diagnosis of the pregnancy-associated diseases. Recent studies have demonstrated that pEXO play a key role in the establishment of maternal immune tolerance, which is critical for a successful pregnancy. To gain a better understanding of the underlying mechanism, we highlighted the advanced studies of pEXO on immune cells in pregnancy.

Immunomodulation of T Helper Cells by Tumor Microenvironment in Oral Cancer Is Associated With CCR8 Expression and Rapid Membrane Vitamin D Signaling Pathway

The immune system plays a key role in the protective response against oral cancer; however, the tumor microenvironment (TME) impairs this anti-cancer response by modulating T helper (Th) responses and promoting an anti-inflammatory environment. Regulatory T cells (Tregs) and Th2 effector cells (Teff) are associated with poor prognosis in oral squamous cell carcinoma (OSCC). However, the main immunomodulatory mechanisms associated with the enrichment of these subsets in OSCC remain unknown. We characterized Th-like lineages in Tregs and Teff and evaluated immunomodulatory changes induced by the TME in OSCC. Our phenotypic data revealed a higher distribution of tumour-infiltrating CCR8⁺ and Th2-like Treg in OSCC compared with non-malignant samples, whereas the percentages of Th1 cells were reduced in cancer. We then analyzed the direct effect of the TME by exposing T cell subsets to cancer secretomes and observed the OSCC secretome induced CCR8 expression and reduced cytokine production from both subsets. Transcriptomic analysis showed that the co-culture with OSCC secretome induced several gene changes associated with the vitamin D (VitD) signaling pathway in T cells. In addition, proteomic analysis identified the presence of several proteins associated with prostaglandin E2 (PGE2) production by rapid membrane VitD signaling and a reduced presence of the VitD binding protein. Thus, we analyzed the effect of VitD and PGE2 and observed that VitD promotes a regulatory Th2-like response with CCR8 expression whilst PGE2 also modulated CCR8 but inhibited cytokine production in combination with VitD. Finally, we evaluated the presence of CCR8 ligand in OSCC and observed increased chemokine CCL18, which was also able to upregulate CCR8 in activated Th cells. Overall, our data showed the immunomodulatory changes induced by the TME involving CCR8 expression and regulatory Th2 phenotypes, which are associated with PGE2 mediated VitD signaling pathway and CCL18 expression in OSCC.

Multifaceted Roles of Adipose Tissue-Derived Exosomes in Physiological and Pathological Conditions

Adipose tissue functions importantly in the bodily homeostasis and systemic metabolism, while obesity links to multiple disorders. Beyond the canonical hormones, growth factors and cytokines, exosomes have been identified to play important roles in transmission of information from adipose tissue to other organs. Exosomes are nanoscale membrane vesicles secreted by donor cells, and transfer the genetic information to the recipient cells where the encapsulated nucleic acids and proteins are released. In this review, we elaborate the recent advances in the biogenesis and profiling of adipose tissue derived exosomes, and their physiological and pathological effects on different organs. Moreover, the potential significance of the exosomes as therapeutic vehicles or drugs is also discussed.