Stem cells in the treatment of diabetes mellitus - Focus on mesenchymal stem cells

Do human adipose stem cell-derived artificial insulin-producing cells develop tumorigenic characteristics throughout differentiation?

BACKGROUND

Artificial insulin-producing cells (IPCs) used to treat diabetes mellitus type 1 (DMT1) are naturally hampered by their carcinogenicity. This in vitro study aimed to examine the carcinogenic potential of IPCs produced by the differentiation of human adipose tissue-derived mesenchymal stem cells (hADSCs).

METHODS AND RESULTS

hADSCs were transformed into IPCs by administering insulin-transferrin, selenium (ITS), and nicotinamide in a 14-day differentiation protocol. The cells were transfected with 20 μg of pure Pdx1-pIRES recombinant vector on the tenth day of differentiation. The successful transfection was confirmed by Pdx1 overexpression and GFP fluorescence activity. The differentiated cells' capacity to release insulin and glucose-dependent C-peptide was used to evaluate their functionality. Gene expression was assessed using real-time PCR. Meanwhile, protein expression was investigated using western blotting. The transfected cells exhibited fluorescence activity and Pdx1 overexpression. The differentiated IPCs were able to secrete C-peptide and insulin. The artificial IPCs showed significantly reduced Oct4 and Nanog expression. However, the differentiation process induced a noticeable elevation in tPA expression. The artificial IPCs expressed much lower c-MYC expression compared to undifferentiated hADSCs. The differentiated cells exhibited a significant elevation in Glut2, MMP-2, CD24, P16, and P21 expression.

CONCLUSIONS

The differentiation technique used in this work produced functional beta-like cells devoid of typical markers of stem cells. The synthetic IPCs displayed characteristics of newly generated β-like cells. The artificial IPCs showed no signs of expressing tumor-associated markers. The findings imply that the artificial IPC cells lack tumor characteristics in vitro.

Cell membrane-derived nanovesicles as extracellular vesicle-mimetics in wound healing

Cell membrane-derived nanovesicles (NVs) have emerged as promising alternatives to extracellular vesicles (EVs) for wound healing applications, addressing the limitations of traditional EVs, which include insufficient targeting capability, low production yield, and limited drug-loading capacity. Through mechanical cell extrusion methods, NVs exhibit superior characteristics, demonstrating enhanced yield, stability, and purity compared to natural EVs. These NVs can be derived from various membrane sources, including single cell types (stem cells, blood cells, immune cells, and bacterial membranes), hybrid cell membranes and cell membranes mixed with liposomes, with each offering unique therapeutic properties. The integration of genetic engineering and surface modifications has further enhanced NV functionality, enabling precise targeting and improved drug delivery capabilities. Recent advances in NV-based therapies have demonstrated their potential across multiple biomedical applications. Although challenges persist in terms of standardization, storage stability, and clinical translation, the combination of natural cell-derived functions with artificial modification potential positions NVs as a promising platform for next-generation therapeutic delivery systems, thereby offering new possibilities in wound healing applications. Finally, we explore the challenges and future prospects of translating NV-based therapeutics into clinical practice, providing insights into the future development of this innovative approach in wound healing and tissue repair.

Thyroid Hormone Activation Regulates the Crosstalk between Breast Cancer and Mesenchymal Stem Cells

BACKGROUND

Thyroid Hormones (THs) critically impact human cancer. Although endowed with both tumor-promoting and inhibiting effects in different cancer types, excess of THs has been linked to enhanced tumor growth and progression. Breast cancer depends on the interaction between bulk tumor cells and the surrounding microenvironment in which mesenchymal stem cells (MSCs) exert powerful pro-tumorigenic activities.

METHODS

Primary human MSCs from healthy female donors were co-cultured with DIO2 knock out (D2KO) and wild type (WT) MCF7 breast cancer cells to assess cell growth, migration, invasion and the expression of known epithelial-mesenchymal transition (EMT)- and inflammation-related markers. Furthermore, a surgery-free intraductal delivery model, i.e., the Mouse-INtraDuctal (MIND) injection method, was used as a tool for in vivo characterization of breast tumor formation and progression.

RESULTS

In this study, we uncovered a novel role of THs in regulating the tumor-stroma crosstalk. MCF7 cells enhanced the intracellular activation of THs through the TH-activating enzyme, D2, fostering their EMT properties and the dialogue with MSCs. D2 inactivation reduced the invasiveness of MCF7 cells and their responsiveness to the pro-tumorigenic induction via MSCs, both in vivo and in vitro.

CONCLUSIONS

Thus, we argue that intracellular activation of THs via D2 is a critical requirement for invasive and metastatic conversion of breast cancer cells, advising the blocking of D2 as a potential therapeutic tool for cancer therapy.

The Diurnal Variation in Mitochondrial Gene in Human Type 2 Diabetic Mesenchymal Stem Cell Grafts

The application of regenerative therapy through stem cell transplantation has emerged as a promising avenue for the treatment of diabetes mellitus (DM). Transplanted tissue homeostasis is affected by disturbances in the clock genes of stem cells. The aim of this study is to investigate the diurnal variation in mitochondrial genes and function after transplantation of adipose-derived mesenchymal stem cells (T2DM-ADSCs) from type 2 diabetic patients into immunodeficient mice. Diurnal variation in mitochondrial genes was assessed by next-generation sequencing. As a result, the diurnal variation in mitochondrial genes showing troughs at ZT10 and ZT22 was observed in the group transplanted with adipose-derived mesenchymal stem cells derived from healthy individuals (N-ADSC). On the other hand, in the group transplanted with T2DM-ADSCs, diurnal variation indicative of troughs was observed at ZT18, with a large phase and amplitude deviation between the two groups. To evaluate the diurnal variation in mitochondrial function, we quantified mitochondrial DNA copy number using the Human mtDNA Monitoring Primer Set, measured mitochondrial membrane potential using JC-1, and evaluated mitophagy staining. The results showed a diurnal variation in mitochondrial DNA copy number, mitophagy, mitochondrial membrane potential, and NF-kB signaling in the N-ADSC transplant group. In contrast, no diurnal variation was observed in T2DM-ADSC transplants. The diurnal variation in mitochondrial function revealed in this study may be a new marker for the efficiency of T2DM-ADSC transplantation.

The Potential of Mesenchymal Stem Cell-Derived Exosomes to Treat Diabetes Mellitus

Diabetes mellitus (DM) is a fatal metabolic disease characterized by persistent hyperglycemia. In recent studies, mesenchymal stem cell (MSC)-derived exosomes, which are being investigated clinically as a cell-free therapy for various diseases, have gained attention due to their biomimetic properties that closely resemble natural cellular communication systems. These MSC-derived exosomes inherit the regenerative and protective effects from MSCs, inducing pancreatic β-cell proliferation and inhibiting apoptosis, as well as ameliorating insulin resistance by suppressing the release of various inflammatory cytokines. Consequently, MSC-derived exosomes have attracted attention as a novel treatment for DM as an alternative to stem cell therapy. In this review, we will introduce the potential of MSC-derived exosomes for the treatment of DM by discussing the studies that have used MSC-derived exosomes to treat DM, which have shown therapeutic effects in both type 1 and type 2 DM.

A biomimetic 3D DNA nanoplatform for enhanced capture and high-purity isolation of stem cell exosomes

Exosomes are uniformly sized vesicle-like bodies that cells secrete. Researchers now believe that exosomes can mediate various health and pathological processes. However, because the biophysical properties of exosomes are similar to those of other cell secretion products and biological fluids are rich and diverse, their separation and purification have always been challenging. Inspired by the adhesive domains in the tentacles of marine organisms that effectively capture and release mobile food particles, we have built a biomimetic 3D DNA nanoplatform. This platform not only captures exosomes efficiently but also allows for light-controlled exosome release. The surface of the 3D DNA nanoplatform can grow multivalent aptamers via rolling circle amplification. Aptamers fold into specific secondary structures that bind to CD63, a protein expressed on the surface of exosomes, enabling efficient exosome capture. As a photothermal reagent, the temperature of the DNA nanoplatform increases under near-infrared light irradiation, destroying the secondary structure of the CD63 aptamer and releasing the exosomes. Additionally, we have demonstrated that a 3D DNA nanoplatform with multivalent CD63 aptamer structures achieves more efficient and convenient stem cell exosome separation compared to ultracentrifugation. This strategy provides an efficient and high-purity way to capture and reversibly separate exosomes, and the separated ultrapure exosomes are used for enhancing wound healing by modulating migration and angiogenesis.

From stem cells to pancreatic β-cells: strategies, applications, and potential treatments for diabetes

Loss and functional failure of pancreatic β-cells results in disruption of glucose homeostasis and progression of diabetes. Although whole pancreas or pancreatic islet transplantation serves as a promising approach for β-cell replenishment and diabetes therapy, the severe scarcity of donor islets makes it unattainable for most diabetic patients. Stem cells, particularly induced pluripotent stem cells (iPSCs), are promising for the treatment of diabetes owing to their self-renewal capacity and ability to differentiate into functional β-cells. In this review, we first introduce the development of functional β-cells and their heterogeneity and then turn to highlight recent advances in the generation of β-cells from stem cells and their potential applications in disease modeling, drug discovery and clinical therapy. Finally, we have discussed the current challenges in developing stem cell-based therapeutic strategies for improving the treatment of diabetes. Although some significant technical hurdles remain, stem cells offer great hope for patients with diabetes and will certainly transform future clinical practice.

Therapeutic Interventions for Diabetes Mellitus-associated Complications

BACKGROUND

Diabetes Mellitus (DM) is an alarming health concern, affecting approximately 537 million people worldwide. As a leading cause of morbidity and mortality, DM demands a comprehensive understanding of its diverse pathophysiological mechanisms and disease progression.

METHODS

This traditional review has consolidated literature on the pathogenesis of hyperglycemia, its progression into complications, and advances in optimal treatment strategies. The literature in the last two decades has been reviewed using several keywords, including "diabetes," "diabetes-associated complications", "novel therapeutic interventions for diabetes-associated diseases", "phyto-extracts as antidiabetic drugs", etc. in prominent databases, such as PubMed, Scopus, Google Scholar, Web of Science, and ClinicalTrials.gov.

RESULTS

We have discussed macrovascular and microvascular complications, such as atherosclerosis, cardiovascular disease, Peripheral Arterial Disease (PAD), stroke, diabetic nephropathy, retinopathy, and neuropathy, as well as various pharmacological and non-pharmacological interventions that are currently available for the management of DM. We have also focused on the potential of natural products in targeting molecular mechanisms involved in carbohydrate metabolism, insulin production, repair of pancreatic cells, and reduction of oxidative stress, thereby contributing to their antidiabetic activity. Additionally, novel therapeutic approaches, like genetic, stem cell, and immunomodulatory therapies, have been explored. We have also discussed the benefits and limitations of each intervention, emerging research and technologies, and precision medicine interventions.

CONCLUSION

This review has emphasized the need for an improved understanding of these advancements, which is essential to enhance clinicians' ability to identify the most effective therapeutic interventions.

Mesenchymal stem cells for osteoarthritis: Recent advances in related cell therapy

Osteoarthritis (OA) is a degenerative joint disease that affects the entire joint and has been a huge burden on the health care system worldwide. Although traditional therapy and targeted cartilage cell therapy have made significant progress in the treatment of OA and cartilage regeneration, there are still many problems. Mesenchymal stem cells from various tissues are the most studied cell type and have been used in preclinical and clinical studies of OA, because they are more widely available, have a greater capacity for in vitro expansion, and have anti-inflammatory and immunomodulatory properties compared to autologous chondrocytes. This article will systematically review the latest developments in these areas. It may provide new insights for improving OA and cartilage regeneration.

HucMSCs can alleviate abnormal vasculogenesis induced by high glucose through the MAPK signaling pathway

Vascular complications caused by diabetes mellitus contribute a major threat to increased disability and mortality of diabetic patients, which are characterized by damaged endothelial cells and angiogenesis. Human umbilical cord-derived mesenchymal stem cells (hucMSCs) have been demonstrated to alleviate endothelial cell damage and improve angiogenesis. However, these investigations overlooked the pivotal role of vasculogenesis. In this study, we utilized blood vessel organoids (BVOs) to investigate the impact of high glucose on vasculogenesis and subsequent angiogenesis. We found that BVOs in the vascular lineage induction stage were more sensitive to high glucose and more susceptible to affect endothelial cell differentiation and function. Moreover, hucMSCs can alleviate the high glucose-induced inhibition of endothelial cell differentiation and dysfunction through MAPK signaling pathway downregulation, with the MAPK activator dimethyl fumarate further illustrating the results. Thereby, we demonstrated that high glucose can lead to abnormal vasculogenesis and impact subsequent angiogenesis, and hucMSCs can alleviate this effect.

Circadian Rhythms of Clock Genes After Transplantation of Mesenchymal Stem Cells with Type 2 Diabetes Mellitus

Regenerative therapy involving stem cell transplantation has become an option for the radical treatment of diabetes mellitus. Disruption in the clock genes of stem cells affects the homeostasis of transplanted tissues. We examined the circadian rhythm of genes in transplanted adipose-derived mesenchymal stem cells derived from a patient with type 2 diabetes mellitus (T2DM-ADSC). The clock genes (PER2, CLOCK1, CRY1, and ARNTL[BMAL1]) exhibited similar daily fluctuations in phase and amplitude between a group transplanted with adipose-derived mesenchymal stem cells derived from a healthy individual (N-ADSC) and a group transplanted with T2DM-ADSC. The findings demonstrated that clock genes in stem cells are synchronized with those in living organisms. Next-generation sequencing was then employed to categorize genes that exhibited variation in expression between N-ADSC and T2DM-ADSC. MTATP8P1 and NDUFA7_2 gene expression was significantly reduced at two time points (ZT6 and ZT18), and daily fluctuations were lost. The present study reports, for the first time, that the circadian rhythms of MTATP8P1 and NDUFA7_2, genes involved in mitochondrial processes, are altered in T2DM-ADSC.

Wharton's Jelly Mesenchymal Stem Cell Conditioned Medium Ameliorates Diabetes-Induced Testicular Damage and Sperm Abnormalities by Mitigating Oxidative Stress, Apoptosis, and Inflammation

Diabetes leads to testicular damage and infertility. Mesenchymal stem cells and their secretory trophic factors have shown potential as regenerative therapies for diabetes and its associated complications. This study examined the effects of conditioned medium derived from Wharton's jelly mesenchymal stem cells (WJMSCs-CM) on sperm parameters, reproductive hormones, biochemical parameters, and histological changes in the testes of diabetic rats. Fifty-six male Sprague-Dawley rats (250-300 g) were assigned to eight groups: control, diabetes, and six diabetic groups receiving early or late treatments with WJMSCs-CM (D-CME, D-CML), insulin (D-INSE, D-INSL), or DMEM (D-DME, D-DML). In the early treatment groups, insulin (3 U/day, subcutaneously) and WJMSCs-CM (10 mg/week, intraperitoneally) were administered immediately after diabetes induction; in the late treatment groups, these interventions began 30 days postinduction. Blood glucose and insulin levels, along with sperm parameters, were assessed. Sex hormones, testicular antioxidant enzyme activity, malondialdehyde (MDA), and glutathione (GSH) concentrations were measured using colorimetric methods. Real-time PCR detected Bax, Bcl-2, and tumor necrosis factor-alpha (TNF-α) gene expression. Our results showed that diabetes increased blood glucose levels, decreased insulin and sex hormone levels, induced testicular oxidative stress and apoptosis, and reduced sperm parameters compared to the control. WJMSCs-CM significantly ameliorated hyperglycemia, increased insulin and sex hormone levels, and improved sperm quality. In WJMSCs-CM-treated diabetic rats, MDA levels were reduced, while GSH and antioxidant enzyme activity increased. Furthermore, WJMSCs-CM decreased the testicular Bax/Bcl-2 ratio and TNF-α expression, as well as enhanced spermatogenic, Sertoli, and Leydig cells. In conclusion, WJMSC-CM administration effectively mitigated diabetes-induced testicular damage by reducing oxidative stress, inflammation, and apoptosis. Early treatment with WJMSCs-CM was more effective than late treatment for diabetes-induced reproductive dysfunction.

The Angiogenic Repertoire of Stem Cell Extracellular Vesicles: Demystifying the Molecular Underpinnings for Wound Healing Applications

Stem cells-derived extracellular vesicles (SC-EVs) have emerged as promising therapeutic agents for wound repair, recapitulating the biological effects of parent cells while mitigating immunogenic and tumorigenic risks. These EVs orchestrate wound healing processes, notably through modulating angiogenesis-a critical event in tissue revascularization and regeneration. This study provides a comprehensive overview of the multifaceted mechanisms underpinning the pro-angiogenic capacity of EVs from various stem cell sources within the wound microenvironment. By elucidating the molecular intricacies governing their angiogenic prowess, we aim to unravel the mechanistic repertoire underlying their remarkable potential to accelerate wound healing. Additionally, methods to enhance the angiogenic effects of SC-EVs, current limitations, and future perspectives are highlighted, emphasizing the significant potential of this rapidly advancing field in revolutionizing wound healing strategies.

Bioengineered mesenchymal stem cell-derived exosomes: emerging strategies for diabetic wound healing

Diabetic wounds are among the most common complications of diabetes mellitus and their healing process can be delayed due to persistent inflammatory reactions, bacterial infections, damaged vascularization and impaired cell proliferation, which casts a blight on patients'health and quality of life. Therefore, new strategies to accelerate diabetic wound healing are being positively explored. Exosomes derived from mesenchymal stem cells (MSC-Exos) can inherit the therapeutic and reparative abilities of stem cells and play a crucial role in diabetic wound healing. However, poor targeting, low concentrations of therapeutic molecules, easy removal from wounds and limited yield of MSC-Exos are challenging for clinical applications. Bioengineering techniques have recently gained attention for their ability to enhance the efficacy and yield of MSC-Exos. In this review, we summarise the role of MSC-Exos in diabetic wound healing and focus on three bioengineering strategies, namely, parental MSC-Exos engineering, direct MSC-Exos engineering and MSC-Exos combined with biomaterials. Furthermore, the application of bioengineered MSC-Exos in diabetic wound healing is reviewed. Finally, we discuss the future prospects of bioengineered MSC-Exos, providing new insights into the exploration of therapeutic strategies.

Hydrogel-Encapsulated Pancreatic Islet Cells as a Promising Strategy for Diabetic Cell Therapy

Islet transplantation has now become a promising treatment for insulin-deficient diabetes mellitus. Compared to traditional diabetes treatments, cell therapy can restore endogenous insulin supplementation, but its large-scale clinical application is impeded by donor shortages, immune rejection, and unsuitable transplantation sites. To overcome these challenges, an increasing number of studies have attempted to transplant hydrogel-encapsulated islet cells to treat diabetes. This review mainly focuses on the strategy of hydrogel-encapsulated pancreatic islet cells for diabetic cell therapy, including different cell sources encapsulated in hydrogels, encapsulation methods, hydrogel types, and a series of accessorial manners to improve transplantation outcomes. In addition, the formation and application challenges as well as prospects are also presented.

Comparative Evaluation of the Differentiation and Proliferation Potential of Dental Pulp Stem Cells on Hydroxyapatite/Beta-Tricalcium Bone Graft and Bovine Bone Graft: An In Vitro Study

BACKGROUND

Stem cells of mesenchymal origin have good proliferative capacity when compared to other stem cell types. Dental pulp stem cells (DPSCs) are a variety of mesenchymal cells obtained from the pulpal tissue of teeth and are abundantly available and easy to obtain. DPSCs facilitate and improve the formation of new bone using different bone graft scaffolds. This present study aims to evaluate and compare the osteogenic potential of DPSCs on alloplastic and xenogeneic bone grafts.

MATERIALS AND METHODS

Hydroxyapatite and beta-tricalcium bone graft and bovine bone graft were used in a triplicate manner in the laboratory. DPSCs were obtained from the pulpal tissue of extracted third molars in the laboratory. The cytotoxicity, osteogenic potential, and difference in the rate of proliferation of mesenchymal cells on the biomaterials were assessed.

RESULTS

Darker purple staining was seen in the case of hydroxyapatite/beta-tricalcium bone graft on MTT colorimetric assay stating that there was an increase in cell viability in hydroxyapatite/beta-tricalcium bone graft as compared to the bovine bone graft. Hydroxyapatite/beta-tricalcium bone graft showed more osteogenic potential as compared to the bovine bone graft as a higher degree of red staining was seen in Alizarin staining.

CONCLUSION

Higher cell viability and higher osteogenic proliferation and differentiation were seen on the hydroxyapatite/beta-tricalcium bone graft compared to the bovine bone scaffold.

Multifunctional Hydrogel of Recombinant Humanized Collagen Loaded with MSCs and MnO2 Accelerates Chronic Diabetic Wound Healing

Chronic wound repair is a clinical treatment challenge. The development of multifunctional hydrogels is of great significance in the key aspects of treating chronic wounds, including reducing oxidative stress, promoting angiogenesis, and improving the natural remodeling of extracellular matrix and immune regulation. In this study, we prepared a composite hydrogel, sodium alginate (SA)@MnO2/recombinant humanized collagen III (RHC)/mesenchymal stem cells (MSCs), composed of SA, MnO2 nanoparticles, RHC, and MSCs. The hydrogel has high mechanical properties and good biocompatibility. In vitro, SA@MnO2/RHC/MSCs hydrogel effectively enhanced the formation of intricate tubular structures and angiogenesis and showed synergistic effects on cell proliferation and migration. In vivo, the SA@MnO2/RHC/MSCs hydrogel enhanced diabetes wound healing, rapid re-epithelization, favorable collagen deposition, and abundant wound angiogenesis. These findings demonstrated that the combined effects of SA, MnO2, RHC, and MSCs synergistically accelerate healing, resulting in a reduced healing time. These observed healing effects demonstrated the potential of this multifunctional hydrogel to transform chronic wound care and improve patient outcomes.

The Immunomodulatory effect of exosomes in diabetes: a novel and attractive therapeutic tool in diabetes therapy

Exosomes carry proteins, metabolites, nucleic acids and lipids from their parent cell of origin. They are derived from cells through exocytosis, are ingested by target cells, and can transfer biological signals between local or distant cells. Therefore, exosomes are often modified in reaction to pathological processes, including infection, cancer, cardiovascular diseases and in response to metabolic perturbations such as obesity and diabetes, all of which involve a significant inflammatory aspect. Here, we discuss how immune cell-derived exosomes origin from neutrophils, T lymphocytes, macrophages impact on the immune reprogramming of diabetes and the associated complications. Besides, exosomes derived from stem cells and their immunomodulatory properties and anti-inflammation effect in diabetes are also reviewed. Moreover, As an important addition to previous reviews, we describes promising directions involving engineered exosomes as well as current challenges of clinical applications in diabetic therapy. Further research on exosomes will explore their potential in translational medicine and provide new avenues for the development of effective clinical diagnostics and therapeutic strategies for immunoregulation of diabetes.

Differentiation of placenta-derived MSCs cultured in human platelet lysate: a xenofree supplement

In the last few decades, mesenchymal stem cells (MSCs)-based regenerative therapies in clinical applications have gradually become a hot topic due to their long-term self-renewal and multilineage differentiation ability. In this scenario, placenta (p) has been considered as a good source of MSCs. As a tissue of fetal origin with abundant number of stem cells compared to other sources, their non-invasive acquisition, strong immunosuppression, and lack of ethical concerns make placenta an indispensable source of MSC in stem cell research and therapy. The mesenchymal stem cells were derived from human term placenta (p-MSCs) in xenofree condition using platelet lysate (PL) as a suitable alternative to fetal bovine serum (FBS). Upon isolation, p-MSCs showed plastic adherence with spindle-shaped, fibroblast-like morphology under microscope. p-MSCs flourished well in PL-containing media. Immunophenotyping showed classical MSC markers (> 90%) and lack expression of hematopoietic and HLA-DR (< 1%). Surprisingly, differentiation study showed differentiation of p-MSCs to mature adipocytes in both induced cells and control (spontaneous differentiation), as observed via oil red staining. This is in line with gene expression data where both control and induced cells were positive for visfatin and leptin. Thus, we propose that p-MSCs can be used for clinical applications in the treatment of various chronic and degenerative diseases.

Epigallocatechin-3-gallate maintains Th1/Th2 response balance and mitigates type-1 autoimmune diabetes induced by streptozotocin through promoting the effect of bone-marrow-derived mesenchymal stem cells

Stem-cell-based therapy is one of the most promising therapeutic strategies owing to its regenerative and immunomodulatory properties. Epigallocatechin-3-gallate (EGCG), a known antioxidant and anti-inflammatory agent, has beneficial effects on cellular protection. We aimed to elucidate the feasibility of using EGCG, along with bone marrow-derived mesenchymal stem cells (BM-MSCs), to improve pancreatic damage through their immune regulatory functions in an experimental model of type 1 diabetes mellitus (T1DM) induced by multiple injections of streptozotocin (STZ). BM-MSCs were isolated from C57BL/6 mice and characterized. The diabetic groups were treated intraperitoneally with PBS, MSCs, EGCG, and a combination of MSCs and EGCG. Real-time PCR assays showed that MSCs with EGCG modulated T-bet and GATA-3 expression and upregulated the mRNA levels of Foxp-3 more efficiently. Analyses of spleen-isolated lymphocytes revealed that combinational treatment pronouncedly increased regulatory cytokines and decreased pro-inflammatory cytokines and splenocyte proliferation. The histopathological assessment demonstrated that co-treatment significantly reduced insulitis and recovered pancreatic islet morphology. Furthermore, the combination of MSCs and EGCG is associated with downregulated blood glucose and enhanced insulin levels. Therefore, combined therapy with EGCG and MSCs holds clinical potential for treating T1DM through synergetic effects in maintaining the Th1/Th2 response balance and promoting the regeneration of damaged pancreatic tissues.

Strategy for Clinical Setting of Co-transplantation of Mesenchymal Stem Cells and Pancreatic Islets

Islet transplantation may be the most efficient therapeutic technique for patients with type 1 diabetes mellitus (T1DM). However, the clinical application of this method is faced with numerous limitations, including isolated islet apoptosis, recipient rejection, and graft vascular reconstruction. Mesenchymal stem cells (MSCs) possess anti-apoptotic, immunomodulatory, and angiogenic properties. Here, we review recent studies on co-culture and co-transplantation of islets with MSCs. We have summarized the methods of preparation of co-transplantation, especially the merits of co-culture, and the effects of co-transplantation. Accumulating experimental evidence shows that co-culture of islets with MSCs promotes islet survival, enhances islet secretory function, and prevascularizes islets through various pretransplant preparations. This review is expected to provide a reference for exploring the use of MSCs for clinical islet co-transplantation.

Extracellular Vesicles Derived from Human Umbilical Cord MSC Improve Vascular Endothelial Function in In Vitro and In Vivo Models of Preeclampsia through Activating Arginine Metabolism

Endothelial cell damage is an important feature of preeclampsia (PE). Human umbilical mesenchymal stem-cell-derived extracellular vesicles (HUMSCs-derived EVs) have been shown to have therapeutic effects on a variety of diseases and tissue damage. However, the therapeutic effect of HUMSCs-derived EVs on endothelial injury in PE remains unclear. This study explored the possible mechanism of HUMSCs-derived EVs in the treatment of endothelial cell injury. Tumor necrosis factor α- and lipopolysaccharide-induced endothelial dysfunction models were used to evaluate the therapeutic effect of HUMSCs-derived EVs on endothelial injury. We further constructed PE mouse models to explore the function of HUMSCs-derived EVs in vivo. The changes of metabolites in endothelial cells after HUMSCs-derived EVs treatment were analyzed by metabolomics analysis and further validated by cell experiments. HUMSCs-derived EVs treatment can alleviate endothelial cell injury in PE, involving cell proliferation, migration, angiogenesis, and anti-inflammatory. Importantly, administration of HUMSCs-derived EVs improves hypertension and proteinuria in PE mice, alleviates kidney damage, and promotes vascularization in the placenta. Furthermore, metabolomics analysis found that the arginine metabolic pathway is activated after HUMSCs-derived EVs treatment. We also observed increased arginine level, nitric oxide content, and nitric oxide synthase activity, and further experiments proved that activating the arginine metabolic pathway could alleviate endothelial dysfunction. Our results reveal that HUMSCs-derived EVs could ameliorate PE endothelial dysfunction by activating the arginine metabolic pathway and may serve as a therapeutic method for treating PE.

Regeneration and anti-inflammatory effects of stem cells and their extracellular vesicles in gynecological diseases

There are many gynecological diseases, among which breast cancer (BC), cervical cancer (CC), endometriosis (EMs), and polycystic ovary syndrome (PCOS) are common and difficult to cure. Stem cells (SCs) are a focus of regenerative medicine. They are commonly used to treat organ damage and difficult diseases because of their potential for self-renewal and multidirectional differentiation. SCs are also commonly used for difficult-to-treat gynecological diseases because of their strong directional differentiation ability with unlimited possibilities, their tendency to adhere to the diseased tissue site, and their use as carriers for drug delivery. SCs can produce exosomes in a paracrine manner. Exosomes can be produced in large quantities and have the advantage of easy storage. Their safety and efficacy are superior to those of SCs, which have considerable potential in gynecological treatment, such as inhibiting endometrial senescence, promoting vascular reconstruction, and improving anti-inflammatory and immune functions. In this paper, we review the mechanisms of the regenerative and anti-inflammatory capacity of SCs and exosomes in incurable gynecological diseases and the current progress in their application in genetic engineering to provide a foundation for further research.

A Supportive Role of Mesenchymal Stem Cells on Insulin-Producing Langerhans Islets with a Specific Emphasis on The Secretome

Type 1 Diabetes (T1D) is a chronic autoimmune disease characterized by a gradual destruction of insulin-producing β-cells in the endocrine pancreas due to innate and specific immune responses, leading to impaired glucose homeostasis. T1D patients usually require regular insulin injections after meals to maintain normal serum glucose levels. In severe cases, pancreas or Langerhans islet transplantation can assist in reaching a sufficient β-mass to normalize glucose homeostasis. The latter procedure is limited because of low donor availability, high islet loss, and immune rejection. There is still a need to develop new technologies to improve islet survival and implantation and to keep the islets functional. Mesenchymal stem cells (MSCs) are multipotent non-hematopoietic progenitor cells with high plasticity that can support human pancreatic islet function both in vitro and in vivo and islet co-transplantation with MSCs is more effective than islet transplantation alone in attenuating diabetes progression. The beneficial effect of MSCs on islet function is due to a combined effect on angiogenesis, suppression of immune responses, and secretion of growth factors essential for islet survival and function. In this review, various aspects of MSCs related to islet function and diabetes are described.

Understanding Type 2 Diabetes Mellitus Risk Parameters through Intermittent Fasting: A Machine Learning Approach

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by elevated blood glucose levels. Despite the availability of pharmacological treatments, dietary plans, and exercise regimens, T2DM remains a significant global cause of mortality. As a result, there is an increasing interest in exploring lifestyle interventions, such as intermittent fasting (IF). This study aims to identify underlying patterns and principles for effectively improving T2DM risk parameters through IF. By analyzing data from multiple randomized clinical trials investigating various IF interventions in humans, a machine learning algorithm was employed to develop a personalized recommendation system. This system offers guidance tailored to pre-diabetic and diabetic individuals, suggesting the most suitable IF interventions to improve T2DM risk parameters. With a success rate of 95%, this recommendation system provides highly individualized advice, optimizing the benefits of IF for diverse population subgroups. The outcomes of this study lead us to conclude that weight is a crucial feature for females, while age plays a determining role for males in reducing glucose levels in blood. By revealing patterns in diabetes risk parameters among individuals, this study not only offers practical guidance but also sheds light on the underlying mechanisms of T2DM, contributing to a deeper understanding of this complex metabolic disorder.

Intravenous injection of human umbilical cord-derived mesenchymal stem cells ameliorates not only blood glucose but also nephrotic complication of diabetic rats through autophagy-mediated anti-senescent mechanism

BACKGROUND

Diabetic nephropathy (DN) is one of the most severe complications of diabetes mellitus, which is characterized by early occurrence of albuminuria and end-stage glomerulosclerosis. Senescence and autophagy of podocytes play an important role in DN development. Human umbilical cord-derived mesenchymal stem cells (hucMSCs) have potential in the treatment of diabetes and its complications. However, the role of hucMSCs in the treatment of DN and the underlying mechanism remain unclear.

METHODS

In vivo, a streptozotocin-induced diabetic male Sprague Dawley rat model was established to determine the renoprotective effect of hucMSCs on DN by biochemical analysis, histopathology, and immunohistochemical staining of renal tissues. And the distribution of hucMSCs in various organs in rats within 168 h was analyzed. In vitro, CCK8 assay, wound healing assay, and β-galactosidase staining were conducted to detect the beneficial effects of hucMSCs on high glucose-induced rat podocytes. Real-time PCR and western blot assays were applied to explore the mechanism of action of hucMSCs.

RESULTS

The in vivo data revealed that hucMSCs were distributed into kidneys and significantly protected kidneys from diabetic damage. The in vitro data indicated that hucMSCs improved cell viability, wound healing, senescence of the high glucose-damaged rat podocytes through a paracrine action mode. Besides, the altered expressions of senescence-associated genes (p16, p53, and p21) and autophagy-associated genes (Beclin-1, p62, and LC3) were improved by hucMSCs. Mechanistically, hucMSCs protected high glucose-induced injury in rat podocytes by activating autophagy and attenuating senescence through the AMPK/mTOR pathway.

CONCLUSIONS

In conclusion, hucMSCs might be a promising therapeutic strategy for the clinical treatment of DN-induced renal damages.

Biomedical importance of the ubiquitin-proteasome system in diabetes and metabolic transdifferentiation of pancreatic duct epithelial cells into β-cells

The ubiquitin-proteasome system (UPS) is a major pathway for cellular protein degradation. The molecular function of the UPS is the removal of damaged proteins, and this function is applied in many biological processes, including inflammation, proliferation, and apoptosis. Accumulating evidence also suggests that the UPS also has a key role in pancreatic β-cell transdifferentiation in diabetes and can be targeted for treatment of diabetic diseases. In this review, we summarized the mechanistic roles of the UPS in the biochemical activities of pancreatic β-cells, including the role of the UPS in insulin synthesis and secretion, as well as β-cell degradation. Also, we discuss how the UPS mediates the transdifferentiation of pancreatic duct epithelial cells into β-cells as the experimental basis for the development of new strategies for the treatment of diabetes in regenerative medicine.

Metformin coordinates with mesenchymal cells to promote VEGF-mediated angiogenesis in diabetic wound healing through Akt/mTOR activation

INTRODUCTION

Cell therapy with mesenchymal stem cells (MSCs) and biomaterials holds great potential for the treatment of diabetic ulceration; however, the underlying mechanism as well as its compatibility with the first-line anti-diabetic drug, metformin (MTF), has not been well elucidated.

METHODS

MSCs derived from the umbilical cord were labeled with fluorescent proteins, followed by transplantation in a fibrin scaffold (MSCs/FG) onto the STZ-induced diabetic wound in a C57BL6/J mouse model. MTF was administered by oral gavage at a dose of 250 mg/kg/day. The wound healing rate, epithelization, angiogenesis, and underlying mechanism were evaluated in MSCs/FG- and MTF-treated diabetic wounds. Moreover, the dose-dependent effects of MTF and involvement of the Akt/mTOR pathway were analyzed in keratinocyte and fibroblast cultures.

RESULTS

MSCs/FG significantly promoted angiogenesis in diabetic wound healing without signs of differentiation or integration. The recruitment of fibroblasts and keratinocytes by MSCs/FG promotes migration and vascular endothelial growth factor (VEGF) expression in an Akt/mTOR-dependent manner. MTF, which is generally considered a mTOR inhibitor, displayed dose-dependent effects on MSC-unregulated Akt/mTOR and VEGF expression. Oral administration of MTF at an anti-diabetic dosage synergistically acted with MSCs/FG to promote Akt/mTOR activation, VEGF expression, and subsequent angiogenesis in diabetic wounds; however, it reduced the survival of MSCs.

CONCLUSIONS

Our study identifies that MTF coordinates with mesenchymal cells to promote Akt/mTOR activation and VEGF-mediated angiogenesis during diabetic wound healing. These findings offer new insights into MSCs engraftment in FG scaffolds for diabetic wound healing and provide support for the promotion of MSCs therapy in patients prescribed with MTF.

Kidney Mesenchymal stem cells alleviate cisplatin-induced kidney injury and apoptosis in rats

OBJECTIVE

This experiment was designed to demonstrate Mesenchymal stem cells (MSCs) derived from kidney can alleviate cisplatin-induced kidney injury and renal cell apoptosis through paracrine pathway.

METHODS

Firstly, MSCs were isolated from kidney of young rats, and their surface-specific markers were identified by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and immunofluorescence staining. Self-renewal ability of Kidney Mesenchymal Stem Cells (KMSCs) was observed by cell counting and 5-Bromo-2'-deoxyuridine (BrdU) fluorescence staining. KMSCs at logarithmic growth stage were traced and injected into rat through tail vein.

RESULTS

The results showed that KMSCs homed in the kidney tissues, decreased the secretion of inflammatory factors (CRP, TNFα, IL-1β, IL-6), and alleviated renal function. Hematoxylin and Eosin (H＆E), Masson and Periodic Acid-silver Methenamine (PASM) staining showed that KMSCs could alleviate pathological damage in rats. Terminal Deoxynucleotidyl Transferase mediated dUTP Nick-End Labeling (TUNEL) assay showed that KMSCs could reduce the apoptosis of rat kidney cells induced by cisplatin. Finally, Immunohistochemistry (IHC) results showed that cisplatin could induce higher expression of the pro-apoptotic protein Bax and lower expression of anti-apoptotic Bcl-2 in kidney tissues. However, KMSCs could reverse the pro-apoptotic effect of cisplatin on kidney cells and improve the survival rate of rats.

CONCLUSIONS

In conclusion, KMSCs were successfully isolated from kidney tissues, and KMSCs have therapeutic effects on rat kidney injury induced by cisplatin.

In vitro comparison of the osteogenic capability of human pulp stem cells on alloplastic, allogeneic, and xenogeneic bone scaffolds

BACKGROUND

A rigorous search for alternatives to autogenous bone grafts to avoid invasiveness at the donor site in the treatment of maxillomandibular bone defects. Researchers have used alloplastic, allogeneic, and xenogeneic bone graft substitutes in clinical studies with varying degrees of success, although their in vitro effects on stem cells remain unclear. Dental pulp stem cells (DPSCs) can potentially enhance the bone regeneration of bone graft substitutes. The present in vitro study investigates the osteogenic capability of DPSCs on alloplastic (biphasic calcium phosphate [BCP]), allogeneic (freeze-dried bone allografts [FDBAs]), and xenogeneic (deproteinized bovine bone mineral [DBBM]) bone grafts.

METHODS

Human DPSCs were seeded on 0.5 mg/ml, 1 mg/ml, and 2 mg/ml of BCP, FDBA, and DBBM to evaluate the optimal cell growth and cytotoxicity. Scaffolds and cell morphologies were analyzed by scanning electron microscopy (SEM). Calcein AM and cytoskeleton staining were performed to determine cell attachment and proliferation. Alkaline phosphatase (ALP) and osteogenesis-related genes expressions was used to investigate initial osteogenic differentiation.

RESULTS

Cytotoxicity assays showed that most viable DPSCs were present at a scaffold concentration of 0.5 mg/ml. The DPSCs on the DBBM scaffold demonstrated a significantly higher proliferation rate of 214.25 ± 16.17 (p < 0.001) cells, enhancing ALP activity level and upregulating of osteogenesis-related genes compared with other two scaffolds.

CONCLUSION

DBBP scaffold led to extremely high cell viability, but also promoted proliferation, attachment, and enhanced the osteogenic differentiation capacity of DPSCs, which hold great potential for bone regeneration treatment; however, further studies are necessary.

Immune responses in mildly versus critically ill COVID-19 patients

The current coronavirus pandemic (COVID-19), caused by SARS-CoV-2, has had devastating effects on the global health and economic system. The cellular and molecular mediators of both the innate and adaptive immune systems are critical in controlling SARS-CoV-2 infections. However, dysregulated inflammatory responses and imbalanced adaptive immunity may contribute to tissue destruction and pathogenesis of the disease. Important mechanisms in severe forms of COVID-19 include overproduction of inflammatory cytokines, impairment of type I IFN response, overactivation of neutrophils and macrophages, decreased frequencies of DC cells, NK cells and ILCs, complement activation, lymphopenia, Th1 and Treg hypoactivation, Th2 and Th17 hyperactivation, as well as decreased clonal diversity and dysregulated B lymphocyte function. Given the relationship between disease severity and an imbalanced immune system, scientists have been led to manipulate the immune system as a therapeutic approach. For example, anti-cytokine, cell, and IVIG therapies have received attention in the treatment of severe COVID-19. In this review, the role of immunity in the development and progression of COVID-19 is discussed, focusing on molecular and cellular aspects of the immune system in mild vs. severe forms of the disease. Moreover, some immune- based therapeutic approaches to COVID-19 are being investigated. Understanding key processes involved in the disease progression is critical in developing therapeutic agents and optimizing related strategies.

Type 1 Diabetes Mellitus: A Review on Advances and Challenges in Creating Insulin Producing Devices

Type 1 diabetes mellitus (T1DM) is the most common autoimmune chronic disease in young patients. It is caused by the destruction of pancreatic endocrine β-cells that produce insulin in specific areas of the pancreas, known as islets of Langerhans. As a result, the body becomes insulin deficient and hyperglycemic. Complications associated with diabetes are life-threatening and the current standard of care for T1DM consists still of insulin injections. Lifesaving, exogenous insulin replacement is a chronic and costly burden of care for diabetic patients. Alternative therapeutic options have been the focus in these fields. Advances in molecular biology technologies and in microfabrication have enabled promising new therapeutic options. For example, islet transplantation has emerged as an effective treatment to restore the normal regulation of blood glucose in patients with T1DM. However, this technique has been hampered by obstacles, such as limited islet availability, extensive islet apoptosis, and poor islet vascular engraftment. Many of these unsolved issues need to be addressed before a potential cure for T1DM can be a possibility. New technologies like organ-on-a-chip platforms (OoC), multiplexed assessment tools and emergent stem cell approaches promise to enhance therapeutic outcomes. This review will introduce the disorder of type 1 diabetes mellitus, an overview of advances and challenges in the areas of microfluidic devices, monitoring tools, and prominent use of stem cells, and how they can be linked together to create a viable model for the T1DM treatment. Microfluidic devices like OoC platforms can establish a crucial platform for pathophysiological and pharmacological studies as they recreate the pancreatic environment. Stem cell use opens the possibility to hypothetically generate a limitless number of functional pancreatic cells. Additionally, the integration of stem cells into OoC models may allow personalized or patient-specific therapies.

The role of mesenchymal stem cell-derived EVs in diabetic wound healing

Diabetic foot is one of the most common complications of diabetes, requiring repeated surgical interventions and leading to amputation. In the absence of effective drugs, new treatments need to be explored. Previous studies have found that stem cell transplantation can promote the healing of chronic diabetic wounds. However, safety issues have limited the clinical application of this technique. Recently, the performance of mesenchymal stem cells after transplantation has been increasingly attributed to their production of exocrine functional derivatives such as extracellular vesicles (EVs), cytokines, and cell-conditioned media. EVs contain a variety of cellular molecules, including RNA, DNA and proteins, which facilitate the exchange of information between cells. EVs have several advantages over parental stem cells, including a high safety profile, no immune response, fewer ethical concerns, and a reduced likelihood of embolism formation and carcinogenesis. In this paper, we summarize the current knowledge of mesenchymal stem cell-derived EVs in accelerating diabetic wound healing, as well as their potential clinic applications.

Tissue engineering approaches and generation of insulin-producing cells to treat type 1 diabetes

Tissue engineering (TE) has become a new effective solution to a variety of medical problems, including diabetes. Mesenchymal stem cells (MSCs), which have the ability to differentiate into endodermal and mesodermal cells, appear to be appropriate for this function. The purpose of this review was to evaluate the outcomes of various researches on the insulin-producing cells (IPCs) generation from MSCs with TE approaches to increase efficacy of type 1 diabetes treatments. The search was performed in PubMed/Medline, Scopus and Embase databases until 2021. Studies revealed that MSCs could also differentiate into IPCs under certain conditions. Therefore, a wide range of protocols have been used for this differentiation, but their effectiveness is very different. Scaffolds can provide a microenvironment that enhances the MSCs to IPCs differentiation, improves their metabolic activity and up-regulate pancreatic-specific transcription factors. They also preserve IPCs architecture and enhance insulin production as well as protect against cell death. This systematic review offers a framework for prospective research based on data. In vitro and in vivo evidence suggests that scaffold-based TE can improve the viability and function of IPCs.

The Therapeutic Potential of Mesenchymal Stem Cells in the Treatment of Diabetes Mellitus

Mesenchymal stem cells (MSCs) exist in many tissues and can differentiate into cells of multiple lineages, such as adipocytes, osteoblasts, or chondrocytes. MSC administration has demonstrated therapeutic potential in various degenerative and inflammatory diseases (e.g., graft-vs.-host disease, multiple sclerosis, Crohn's disease, organ fibrosis, and diabetes mellitus [DM]). The mechanisms involved in the therapeutic effects of MSCs are multifaceted. Generally, implanted MSCs can migrate to sites of injury, where they establish an anti-inflammatory and regenerative microenvironment in damaged tissues. In addition, MSCs can modulate innate and adaptive immune responses through immunosuppressive mechanisms that involve immune cells, inflammatory cytokines, chemokines, and immunomodulatory factors. DM has a high prevalence worldwide; it also contributes to a high rate of mortality worldwide. MSCs offer a promising therapeutic agent to prevent or repair damage from DM and diabetic complications through properties such as multilineage differentiation, homing, promotion of angiogenesis, and immunomodulation (e.g., prevention of oxidative stress, fibrosis, and cell death). In this study, we review current findings regarding the immunomodulatory and regenerative mechanisms of MSCs, as well as their therapeutic applications in DM and DM-related complications.

Human Mesenchymal Stem Cell Secretome Driven T Cell Immunomodulation Is IL-10 Dependent

The Human Mesenchymal Stem Cell (hMSC) secretome has pleiotropic effects underpinning its therapeutic potential. hMSC serum-free conditioned media (SFCM) contains a variety of cytokines, with previous studies linking a changed secretome composition to physoxia. The Jurkat T cell model allowed the efficacy of SFCM vs. serum-free media (SFM) in the suppression of immunological aspects, including proliferation and polarisation, to be explored. Cell growth in SFM was higher [(21% O2 = 5.3 × 105 ± 1.8 × 104 cells/mL) and (2% O2 = 5.1 × 105 ± 3.0 × 104 cells/mL)], compared to SFCM [(21% O2 = 2.4 × 105 ± 2.5 × 104 cells/mL) and (2% O2 = 2.2 × 105 ± 5.8 × 103 cells/mL)]. SFM supported IL-2 release following activation [(21% O2 = 5305 ± 211 pg/mL) and (2% O2 = 5347 ± 327 pg/mL)] whereas SFCM suppressed IL-2 secretion [(21% O2 = 2461 ± 178 pg/mL) and (2% O2 = 1625 ± 159 pg/mL)]. Anti-inflammatory cytokines, namely IL-4, IL-10, and IL-13, which we previously confirmed as components of hMSC SFCM, were tested. IL-10 neutralisation in SFCM restored proliferation in both oxygen environments (SFM/SFCM+antiIL-10 ~1-fold increase). Conversely, IL-4/IL-13 neutralisation showed no proliferation restoration [(SFM/SFM+antiIL-4 ~2-fold decrease), and (SFM/SFCM+antiIL-13 ~2-fold decrease)]. Present findings indicate IL-10 played an immunosuppressive role by reducing IL-2 secretion. Identification of immunosuppressive components of the hMSC secretome and a mechanistic understanding of their action allow for the advancement and refinement of potential future cell-free therapies.

Glucose Enhances Pro-Tumorigenic Functions of Mammary Adipose-Derived Mesenchymal Stromal/Stem Cells on Breast Cancer Cell Lines

Adiposity and diabetes affect breast cancer (BC) progression. We addressed whether glucose may affect the interaction between mammary adipose tissue-derived mesenchymal stromal/stem cells (MAT-MSCs) and BC cells. Two-dimensional co-cultures and spheroids were established in 25 mM or 5.5 mM glucose (High Glucose-HG or Low Glucose-LG) by using MAT-MSCs and MCF7 or MDA-MB231 BC cells. Gene expression was measured by qPCR, while protein levels were measured by cytofluorimetry and ELISA. CD44high/CD24low BC stem-like sub-population was quantified by cytofluorimetry. An in vivo zebrafish model was assessed by injecting spheroid-derived labeled cells. MAT-MSCs co-cultured with BC cells showed an inflammatory/senescent phenotype with increased abundance of IL-6, IL-8, VEGF and p16INK4a, accompanied by altered levels of CDKN2A and LMNB1. BC cells reduced multipotency and increased fibrotic features modulating OCT4, SOX2, NANOG, αSMA and FAP in MAT-MSCs. Of note, these co-culture-mediated changes in MAT-MSCs were partially reverted in LG. Only in HG, MAT-MSCs increased CD44high/CD24low MCF7 sub-population and promoted their ability to form mammospheres. Injection in zebrafish embryos of HG spheroid-derived MCF7 and MAT-MSCs was followed by a significant cellular migration and caudal dissemination. Thus, MAT-MSCs enhance the aggressiveness of BC cells in a HG environment.

New therapeutic approaches for type 1 diabetes: Disease-modifying therapies

It has been 100 years since the first successful clinical use of insulin, yet it remains the only treatment option for type 1 diabetes mellitus (T1DM) patients. Advances in diabetes care, such as insulin analogue therapies and new devices, including continuous glucose monitoring with continuous subcutaneous insulin infusion have improved the quality of life of patients but have no impact on the pathogenesis of the disease. They do not eliminate long-term complications and require several lifestyle sacrifices. A more ideal future therapy for T1DM, instead of supplementing the insufficient hormone production (a consequence of β-cell destruction), would also aim to stop or slow down the destructive autoimmune process. The discovery of the autoimmune nature of type 1 diabetes mellitus has presented several targets by which disease progression may be altered. The goal of disease-modifying therapies is to target autoimmune mechanisms and prevent β-cell destruction. T1DM patients with better β-cell function have better glycemic control, reduced incidence of long-term complications and hypoglycemic episodes. Unfortunately, at the time symptomatic T1DM is diagnosed, most of the insulin secreting β cells are usually lost. Therefore, to maximize the salvageable β-cell mass by disease-modifying therapies, detecting autoimmune markers in an early, optimally presymptomatic phase of T1DM is of great importance. Disease-modifying therapies, such as immuno- and regenerative therapies are expected to take a relevant place in diabetology. The aim of this article was to provide a brief insight into the pathogenesis and course of T1DM and present the current state of disease-modifying therapeutic interventions that may impact future diabetes treatment.

Human umbilical cord mesenchymal stem cells ameliorate erectile dysfunction in rats with diabetes mellitus through the attenuation of ferroptosis

Background

Erectile dysfunction (ED), as one of the most prevalent consequences in male diabetic patients, has a serious impact on men's physical and mental health, and the treatment effect of diabetic mellitus erectile dysfunction (DMED) is often worse. Therefore, the development of a novel therapeutic approach is urgent. As stem cells with high differentiation potential, human umbilical cord mesenchymal stem cells (HUCMSCs) have been widely used in the treatment of diseases in other systems, and are expected to be a promising strategy for the treatment of DMED. In this study, we investigated the role of HUCMSCs in managing erectile function in rat models of type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) and compared the effects of two different injection methods.

Methods

T1DM and T2DM ED rats were given labelled HUCMSCs by corpus cavernosum injection and tail vein injection, respectively. ICP and MAP were monitored simultaneously by electrical stimulation four weeks after injection to indicate the erectile function of rats. To track the development and colonisation capabilities of stem cells, we performed EdU assay with penile tissue. The histological changes of the penis were observed by hematoxylin–eosin staining, and Masson’s trichrome staining was conducted to evaluate the smooth muscle content and the degree of fibrosis in the rat penis. Then, we employed specific kits to measure the level of NO, cGMP, MDA, SOD and Fe in penis. Electron transmission microscopy was implemented to observe morphology of mitochondria. Besides, western blot and immunofluorescence staining were performed to demonstrate the expression of ferroptosis-related genes.

Results

We found that HUCMSCs improved erectile function in T1DM and T2DM ED rats, with no difference in efficacy between corpus cavernosum injection and tail vein injection. The EdU assay revealed that only a tiny percentage of HUCMSCs colonised the corpus cavernosum, while smooth muscle in the penis expanded and collagen decreased following HUCMSC injection. Moreover, the levels of oxidative stress in the penis of the rats given HUCMSCs were dramatically reduced, as was the tissue iron content. HUCMSCs normalised mitochondrial morphology within corpus cavernosum smooth muscle cells (CCSMCs), which were characteristically altered by high glucose. Furthermore, the expression of ferroptosis inhibitory genes SLC7A11 and GPX4 was obviously elevated in CCSMCs after stem cell management, but the abundances of ACSL4, LPCAT3 and ALOX15 showed the polar opposite tendency.

Conclusions

HUCMSCs can effectively and safely alleviate erectile dysfunction in T1DM and T2DM ED rats, while restoring erectile function by attenuating diabetes-induced ferroptosis in CCSMCs. Additionally, this study provides significant evidence for the development of HUCMSCs as a viable therapeutic strategy for DMED.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03147-w.

Strategies for the induction of anti-inflammatory mesenchymal stem cells and their application in the treatment of immune-related nephropathy

Mesenchymal stem cells (MSCs) have potent immunomodulatory functions. Animal studies and clinical trials have demonstrated that MSCs can inhibit immune/inflammatory response in tissues and have good therapeutic effects on a variety of immune-related diseases. However, MSCs currently used for treatment are a mixed, undefined, and heterogeneous cell population, resulting in inconsistent clinical treatment effects. MSCs have dual pro-inflammatory/anti-inflammatory regulatory functions in different environments. In different microenvironments, the immunomodulatory function of MSCs has plasticity; therefore, MSCs can transform into pro-inflammatory MSC1 or anti-inflammatory MSC2 phenotypes. There is an urgent need to elucidate the molecular mechanism that induces the phenotypic transition of MSCs to pro-inflammatory or anti-inflammatory MSCs and to develop technical strategies that can induce the transformation of MSCs to the anti-inflammatory MSC2 phenotype to provide a theoretical basis for the future clinical use of MSCs in the treatment of immune-related nephropathy. In this paper, we summarize the relevant strategies and mechanisms for inducing the transformation of MSCs into the anti-inflammatory MSC2 phenotype and enhancing the immunosuppressive function of MSCs.

Exocrine pancreas regeneration modifies original pancreas to alleviate diabetes in mouse models

Diabetes is a major public health issue because of its widely epidemic nature and lack of cure. Here, we show that pancreas-derived mesenchymal stem cells (PMSCs) are capable of regenerating exocrine pancreas when implanted into the kidney capsule of mice with streptozotocin (STZ)-induced diabetes. Mechanistically, we found that the regenerated exocrine pancreas elevated interleukin-6 (IL-6) in PMSC implants, which transiently activated tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) to inhibit IL-17, thereby rescuing damaged exocrine pancreas and islet β cells. In addition, we used knockout mouse models to show that global lack of IL-6, TNF-α, or IFN-γ resulted in increased severity of STZ-induced diabetes and resistance to PMSC implantation therapy, confirming the roles of these factors in safeguarding pancreatic β cells. Furthermore, removal of the kidney capsule PMSC implants at 28 days after implantation did not affect the PMSC-initiated therapeutic effect on diabetic mice. This study reveals a previously unknown role of exocrine pancreas regeneration in safeguarding β cells and demonstrates a "soil-rescues-seed" strategy for type 1 diabetes therapy.

Bone marrow mesenchymal stromal cells for diabetes therapy: touch, fuse, and fix?

Bone marrow mesenchymal stromal cells (BM-MSCs) have anti-inflammatory and pro-survival properties. Naturally, they do not express human leukocyte antigen class II surface antigens and have immunosuppressive capabilities. Together with their relatively easy accessibility and expansion, they are an attractive tool for organ support in transplantation and regenerative therapy. Autologous BM-MSC transplantation alone or together with transplanted islets improves β-cell function, graft survival, and glycemic control in diabetes. Albeit MSCs’ capacity to transdifferentiate into β-cell is limited, their protective effects are mediated mainly by paracrine mechanisms through BM-MSCs circulating through the body. Direct cell–cell contact and spontaneous fusion of BM-MSCs with injured cells, although at a very low rate, are further mechanisms of their supportive effect and for tissue regeneration. Diabetes is a disease of long-term chronic inflammation and cell therapy requires stable, highly functional cells. Several tools and protocols have been developed by mimicking natural fusion events to induce and accelerate fusion in vitro to promote β-cell-specific gene expression in fused cells. BM-MSC-islet fusion before transplantation may be a strategy for long-term islet survival and improved function. This review discusses the cell-protective and anti-inflammatory characteristics of BM-MSCs to boost highly functional insulin-producing cells in vitro and in vivo, and the efficacy of their fusion with β-cells as a path to promote β-cell regeneration.

Pro-α-cell-derived β-cells contribute to β-cell neogenesis induced by antagonistic glucagon receptor antibody in type 2 diabetic mice

The deficiency of pancreatic β-cells is the key pathogenesis of diabetes, while glucagon-secreting α-cells are another player in the development of diabetes. Here, we aimed to investigate the effects of glucagon receptor (GCGR) antagonism on β-cell neogenesis in type 2 diabetic (T2D) mice and explore the origins of the neogenic β-cells. We showed that GCGR monoclonal antibody (mAb) elevated plasma insulin level and increased β-cell mass in T2D mice. By using α-cell lineage-tracing (glucagon-cre-β-gal) mice and inducible Ngn3⁺ pancreatic endocrine progenitor lineage-tracing (Ngn3-CreERT2-tdTomato) mice, we found that GCGR mAb treatment promoted α-cell regression to progenitors, and induced Ngn3⁺ progenitor reactivation and differentiation toward β-cells. Besides, GCGR mAb upregulated the expression levels of β-cell regeneration-associated genes and promoted insulin secretion in primary mouse islets, indicative of a direct effect on β-cell identity. Our findings suggest that GCGR antagonism not only increases insulin secretion but also promotes pro-α-cell-derived β-cell neogenesis in T2D mice.

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Blockage of α-cell-derived glucagon promotes β-cell regeneration in situ in type 2 diabetic (T2D) mice

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Glucagon receptor (GCGR) mAb induces the trans-differentiation of α-cells to β-cells

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GCGR mAb promotes α-cell regression to pancreatic endocrine progenitors

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GCGR mAb induces Ngn3⁺ progenitor reactivation and differentiation toward β-cells

How to Make Sense out of 75,000 Mesenchymal Stromal Cell Publications?

Mesenchymal stromal cells have been the subject of an expanding number of studies over the past decades. Today, over 75,000 publications are available that shine light on the biological properties and therapeutic effects of these versatile cells in numerous pre-clinical models and early-phase clinical trials. The massive number of papers makes it hard for researchers to comprehend the whole field, and furthermore, they give the impression that mesenchymal stromal cells are wonder cells that are curative for any condition. It is becoming increasingly difficult to dissect how and for what conditions mesenchymal stromal cells exhibit true and reproducible therapeutic effects. This article tries to address the question how to make sense of 75,000, and still counting, publications on mesenchymal stromal cells.

The combined therapy of mesenchymal stem cell transplantation and resveratrol for diabetes: Future applications and challenges

Diabetes mellitus (DM) is a worldwide chronic epidemic disease of impaired glucose metabolism. Transplantation of mesenchymal stem cells (MSCs) is considered a promising emerging treatment strategy for diabetes. However, the harsh internal environment of DM patients can inhibit the treatment effects of transplanted MSCs. Fortunately, this adverse effect can be reversed by resveratrol (Res). Therefore, we investigated and summarized relevant studies on the combined treatment of diabetes with MSCs and resveratrol. This review presents the therapeutic effects of this combination therapy strategy on DM in glycemic control, anti-inflammatory, anti-oxidative stress and anti-fibrotic. Moreover, this review explained the mechanisms of MSCs and resveratrol in diabetes treatment from 3 aspects, including promoting cell survival and inhibiting apoptosis, inhibiting histiocyte fibrosis, and improving glucose metabolism. These findings help to understand in-depth mechanisms of the treatment of DM and help to propose a potential treatment strategy for DM and its complications.

Mesenchymal Stem Cells Ameliorate Hyperglycemia in Type I Diabetic Developing Male Rats

One of the most promising treatments for diabetes mellitus (DM) is stem cell therapy. This study is aimed at elucidating the antidiabetic effect of mesenchymal stem cells (MSCs) on streptozotocin- (STZ-) induced DM in developing male rats. Twenty-four male albino rats (4 weeks old) were divided into control, diabetic, diabetic+MSCs1 (received MSCs one week after STZ treatment), and diabetic+MSCs2 (received MSCs 4 weeks after STZ treatment). Diabetic rats showed marked impairment ( $p<0.05$ ) in serum levels of glucose, insulin, C-peptide, glycosylated hemoglobin (HbA1c), malondialdehyde (MDA), total antioxidant status (TAS), and total oxidant status (TOS) in addition to disruption of the calculated values of homeostatic model assessment of insulin resistance (HOMA-IR), pancreatic β cell function (HOMA-β), and oxidative stress index (OSI). These biochemical alterations were confirmed by the histopathological and ultrastructural assessments which showed marked destructive effect on pancreatic islet cells. MSC therapy in an early stage reversed most of the biochemical, histological, and ultrastructural alterations in the STZ-induced diabetic model and restored the normal cellular population of most acinar cells and islet of Langerhans. These results indicate that MSC therapy of STZ-induced diabetic developing rats during an early stage has the capacity of β cell restoration and the control of blood glycemic homeostasis.

Characteristics and regulation of mesenchymal stem cell plasticity by the microenvironment — specific factors involved in the regulation of MSC plasticity

Mesenchymal stem cells (MSCs), multipotent stromal cells, have attracted extensive attention in the field of regenerative medicine and cell therapy due to the capacity of self-renewal, multilineage differentiation, and immune regulation. MSCs have different cellular effects in different diseases, and even have markedly different curative effects with different tissue sources, indicating the plasticity of MSCs. The phenotypes, secreted factors, and proliferative, migratory, differentiating, and immunomodulatory effects of MSCs depend on certain mediators present in their microenvironment. Understanding microenvironmental factors and their internal mechanisms in MSC responses may help in subsequent prediction and improvement of clinical benefits. This review highlighted the recent advances in MSC plasticity in the physiological and pathological microenvironment and multiple microenvironmental factors regulating MSC plasticity. It also highlighted some progress in the underlying molecular mechanisms of MSC remodeling in the microenvironment. It might provide references for the improvement in vitro culture of MSCs, clinical application, and in vivo induction.

Differentiation of multipotent stem cells to insulin-producing cells for treatment of diabetes mellitus: bone marrow- and adipose tissue-derived cells comparison

BACKGROUND

Mesenchymal stem cells (MSCs) from human adipose tissue and bone marrow have a great potential for use in cell therapy due to their ease of isolation, expansion, and differentiation. Our intention was to isolate and promote in vitro expansion and differentiation of MSCs from human adipose and bone marrow tissue into cells with a pancreatic endocrine phenotype and to compare the potency of these cells together.

METHODS AND RESULTS

MSCs were pre-induced with nicotinamide, mercaptoethanol, B-27 and b-FGF in L-DMEM for 2 days and re-induced again in supplemented H-DMEM for another 3 days. Expression of five genes in differentiated beta cells was evaluated by Real-time PCR and western blotting and the potency of insulin release in response to glucose stimulation was evaluated by insulin and C-peptide ELISA kit. The differentiated cells were evaluated by immunocytochemistry staining for Insulin and PDX-1. Quantitative RT-PCR results showed up-regulation of four genes in differentiated beta-islet cells (Insulin, Ngn-3, Pax-4 and Pdx-1) compared with the control. Western blot analysis showed that MSCs cells mainly produced proinsulin and insulin after differentiation but nestin was more expressed in pre-differentiated stem cells. Glucose and insulin secretion assay showed that insulin levels and C-peptide secretion were significantly increased in response to 10 mM glucose.

CONCLUSIONS

Our study showed that both adipose and bone marrow stem cells could differentiate into functional beta-islet cells but it seems that adipose stem cells could be a better choice for treatment of diabetes mellitus according to their higher potency.

Insulin discovery: A pivotal point in medical history

The discovery of insulin in 1921 - due to the efforts of the Canadian research team based in Toronto - has been a landmark achievement in the history of medicine. Lives of people with diabetes were changed forever, considering that in the pre-insulin era this was a deadly condition. Insulin, right after its discovery, became the first hormone to be purified for human use, the first to be unraveled in its amino acid sequence and to be synthetized by DNA-recombinant technique, the first to be modified in its amino acid sequence to modify its duration of action. As such the discovery of insulin represents a pivotal point in medical history. Since the early days of its production, insulin has been improved in its pharmacokinetic and pharmacodynamic properties in the attempt to faithfully reproduce diurnal physiologic plasma insulin fluctuations. The evolution of insulin molecule has been paralleled by evolution in the way the hormone is administered. Once-weekly insulins will be available soon, and glucose-responsive "smart" insulins start showing their potential in early clinical studies. The first century of insulin as therapy was marked by relentless search for better formulations, a search that has not stopped yet. New technologies may have, indeed, the potential to provide further improvement of safety and efficacy of insulin therapy and, therefore, contribute to improvement of the quality of life of people with diabetes.