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

The efficiency of stem cell differentiation into functional beta cells for treating insulin-requiring diabetes: Recent advances and current challenges

In recent years, the potential of stem cells (SCs) to differentiate into various types of cells, including β-cells, has led to a significant boost in development. The efficiency of this differentiation process and the functionality of the cells post-transplantation are crucial factors for the success of stem cell therapy in diabetes. Herein, this article reviews the current advances and challenges faced by stem cell differentiation into functional β-cells for diabetes treatment. In vitro, researchers have sought to enhance the differentiation efficiency of functional β-cells by mimicking the normal pancreatic development process, using gene manipulation, pharmacological and culture conditions stimulation, three-dimensional (3D) and organoid culture, or sorting for functional β-cells based on mature islet cell markers. Furthermore, in vivo studies have also looked at suitable transplantation sites, the enhancement of the transplantation microenvironment, immune modulation, and vascular function reconstruction to improve the survival rate of functional β-cells, thereby enhancing the treatment of diabetes. Despite these advancements, developing stem cells to produce functional β-cells for efficacious diabetes treatment is a continuous research endeavor requiring significant multidisciplinary collaboration, for the stem-cell-derived beta cells to evolve into an effective cellular therapy.

Mitochondria in Mesenchymal Stem Cells: Key to Fate Determination and Therapeutic Potential

Mesenchymal stem cells (MSCs) have become popular tool cells in the field of transformation and regenerative medicine due to their function of cell rescue and cell replacement. The dynamically changing mitochondria serve as an energy metabolism factory and signal transduction platform, adapting to different cell states and maintaining normal cell activities. Therefore, a clear understanding of the regulatory mechanism of mitochondria in MSCs is profit for more efficient clinical transformation of stem cells. This review highlights the cutting-edge knowledge regarding mitochondrial biology from the following aspects: mitochondrial morphological dynamics, energy metabolism and signal transduction. The manuscript mainly focuses on mitochondrial mechanistic insights in the whole life course of MSCs, as well as the potential roles played by mitochondria in MSCs treatment of transplantation, for seeking pivotal targets of stem cell fate regulation and stem cell therapy.

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.

The Role of Mesenchymal Stem/Stromal Cells Secretome in Macrophage Polarization: Perspectives on Treating Inflammatory Diseases

Mesenchymal stem/stromal cells (MSCs) have exhibited potential for treating multiple inflammation- related diseases (IRDs) due to their easy acquisition, unique immunomodulatory and tissue repair properties, and immune-privileged characteristics. It is worth mentioning that MSCs release a wide array of soluble bioactive components in the secretome that modulate host innate and adaptive immune responses and promote the resolution of inflammation. As the first line of defense, macrophages exist throughout the entire inflammation process. They continuously switch their molecular phenotypes accompanied by complementary functional regulation ranging from classically activated pro-inflammatory M1-type (M1) to alternatively activated anti-inflammatory M2-type macrophages (M2). Recent studies have shown that the active intercommunication between MSCs and macrophages is indispensable for the immunomodulatory and regenerative behavior of MSCs in pharmacological cell therapy products. In this review, we systematically summarized the emerging capacities and detailed the molecular mechanisms of the MSC-derived secretome (MSC-SE) in immunomodulating macrophage polarization and preventing excessive inflammation, providing novel insights into the clinical applications of MSC-based therapy in IRD management.

Differentiation of Pancreatic Beta Cells: Dual Acting of Inflammatory Factors

In the past decades, scientists have made outstanding efforts to treat diabetes. However, diabetes treatment is still far from satisfactory due to the complex nature of the disease and the challenges encountered in resolving it. Inflammatory factors are key regulators of the immune system's response to pathological insults, organ neogenesis, rejuvenation of novel cells to replace injured cells and overwhelming disease conditions. Currently, the available treatments for type 1 diabetes include daily insulin injection, pancreatic beta cell or tissue transplantation, and gene therapy. Cell therapy, exploiting differentiation, and reprogramming various types of cells to generate pancreatic insulin-producing cells are novel approaches for the treatment of type 1 diabetes. A better understanding of the inflammatory pathways offers valuable and improved therapeutic options to provide more advanced and better treatments for diabetes. In this review, we investigated different types of inflammatory factors that participate in the pathogenesis of type 1 diabetes, their possible dual impacts on the differentiation, reprogramming, and fusion of other stem cell lines into pancreatic insulin-producing beta cells, and the possibility of applying these factors to improve the treatment of this disease.

Investigation on repairing diabetic foot ulcer based on 3D bio-printing Gel/dECM/Qcs composite scaffolds

Diabetic foot ulcers are one of the most serious of the numerous complications of diabetes mellitus, causing great physical trauma and financial stress to patients, and accelerating wound healing in diabetic patients remains one of the major clinical challenges. Exosomes from adipose-derived stem cells can directly and indirectly promote wound healing. However, due to the low retention rate of exosomes in the wound, exosome treatment is difficult to achieve the expected effect. Therefore, it is of great significance to synthesize a composite scaffold that can stably load exosomes and has antibacterial properties. In this study, fresh pig skin was decellularized to obtain decellularized matrix (dECM). Secondly, quaternized chitosan (Qcs) was modified with quaternary ammonium salt to make it soluble in water after quaternization. Finally, Gel-dECM-Qcs (GDQ) bioink was prepared by adding acellular matrix and quaternized chitosan with temperature sensitive gelatin (Gel) as carrier. Tissue engineered composite scaffolds were then prepared by extrusion 3D printing technology. Subsequently, the physicochemical properties, biocompatibility and antimicrobial capacity of the composite scaffolds were determined, and the data showed that the composite scaffolds had good mechanical properties, biocompatibility and antimicrobial capacity, and the maximum stress of the composite scaffolds was 1.16 ± 0.05 MPa, the composite scaffolds were able to proliferate and adhered to the L929 cells, and the kill rates of composite scaffolds against E. coli and S. aureus after incubation for 24 h were 93.24 ± 1.22 % and 97.34 ± 0.23 %, respectively. Overall, the GDQ composite scaffolds have good mechanical properties adapted to skin bending, its good biocompatibility can promote the growth and migration of fibroblasts, reshape injured tissues, accelerate the wound healing, and excellent antimicrobial ability can inhibit the growth of E. coli and S. aureus, reducing the impact of bacterial infections on wounds. Moreover, the composite scaffolds have the potential to be used as exosom-loaded hydrogel dressings, which provides a basis for the subsequent research on the repair of diabetic foot ulcers.

The ameliorating effects of mesenchymal stem cells compared to α-tocopherol on apoptosis and autophagy in streptozotocin-induced diabetic rats: Implication of PI3K/Akt signaling pathway and entero-insular axis

Bone marrow-derived mesenchymal stem cells (BM-MSCs) are considered a novel regenerative therapy that holds much potential. This study aimed to examine and compare the ameliorative effects of BM-MSCs compared to α-tocopherol (α-Toc) on apoptosis, autophagy, and β-cell function in a rat model of streptozotocin (STZ)-induced diabetes and further analyzed the implications and interrelations of the entero-insular axis, and type I phosphoinositide 3-kinase (PI3K)/Akt signaling. Forty adult male albino rats were categorized into four groups (n = 10, in each): control group, STZ-induced diabetic group (single i.p. injection of STZ 45 mg/kg), diabetic and treated with BM-MSCs injection, diabetic and treatment with α-Toc p.o. The serum glucose, insulin, nitric oxide (NO), and catalase (CAT) were measured. Histopathological examination of the pancreas, the expression levels of insulin, CD44, caspase-3, autophagy markers, P13K/Akt, and pancreas/duodenum homeobox protein 1, in pancreatic tissue, and glucose-dependent insulinotropic polypeptide (GIP) in the duodenum were detected by hematoxylin and eosin staining, immunofluorescence labeling, and by quantitative real-time polymerase chain reaction. The diabetic rats showed reduced insulin, hyperglycemia, nitrosative stress (NO, CAT), augmented apoptosis (caspase 3), impaired autophagy (p62/SQSTM1, LC3), downregulated PI3K/Akt pathway and increased GIP expression, and degeneration of pancreatic islets. Treatment with either BM-MSCs or α-Toc suppressed the nitrosative stress, reduced apoptosis, recovered autophagy, upregulated PI3K/Akt pathway, and subsequently increased insulin levels, decreased blood glucose, and downregulated GIP expression with partial restoration of pancreatic islets. Based on our findings, the cytoprotective effects of BM-MSCs and α-Toc in type 1-induced diabetes appeared to be related to repaired autophagy and recovered PI3K/Akt signaling. Moreover, we reported their novel effects on reversing intestinal GIP expression level. The effect of BM-MSCs was notably superior to that of α-Toc.

Renal cancer secretome induces migration of mesenchymal stromal cells

BACKGROUND

Advanced renal cell carcinoma (RCC) is therapeutically challenging. RCC progression is facilitated by mesenchymal stem/stromal cells (MSCs) that exert remarkable tumor tropism. The specific mechanisms mediating MSCs' migration to RCC remain unknown. Here, we aimed to comprehensively analyze RCC secretome to identify MSCs attractants.

METHODS

Conditioned media (CM) were collected from five RCC-derived cell lines (Caki-1, 786-O, A498, KIJ265T and KIJ308T) and non-tumorous control cell line (RPTEC/TERT1) and analyzed using cytokine arrays targeting 274 cytokines in addition to global CM proteomics. MSCs were isolated from bone marrow of patients undergoing standard orthopedic surgeries. RCC CM and the selected recombinant cytokines were used to analyze their influence on MSCs migration and microarray-targeted gene expression. The expression of genes encoding cytokines was evaluated in 100 matched-paired control-RCC tumor samples.

RESULTS

When compared with normal cells, CM from advanced RCC cell lines (Caki-1 and KIJ265T) were the strongest stimulators of MSCs migration. Targeted analysis of 274 cytokines and global proteomics of RCC CM revealed decreased DPP4 and EGF, as well as increased AREG, FN1 and MMP1, with consistently altered gene expression in RCC cell lines and tumors. AREG and FN1 stimulated, while DPP4 attenuated MSCs migration. RCC CM induced MSCs' transcriptional reprogramming, stimulating the expression of CD44, PTX3 and RAB27B. RCC cells secreted hyaluronic acid (HA), a CD44 ligand mediating MSCs' homing to the kidney. AREG emerged as an upregulator of MSCs' transcription.

CONCLUSIONS

Advanced RCC cells secrete AREG, FN1 and HA to induce MSCs migration, while DPP4 loss prevents its inhibitory effect on MSCs homing. RCC secretome induces MSCs' transcriptional reprograming to facilitate their migration. The identified components of RCC secretome represent potential therapeutic targets.

Review: Research progress of adipose-derived stem cells in the treatment of chronic wounds

Although methods are used to treat wounds clinically, there are still many challenges in the treatment of chronic wounds due to excessive inflammatory response, difficulties in epithelialization, vascularization, and other factors. With the increasing research on adipose-derived stem cells (ADSCs) in recent years, accumulating evidence has shown that ADSCs scan promotes the healing of chronic wounds by regulating macrophage function and cellular immunity and promoting angiogenesis and epithelialization. The present study reviewed the difficulties in the treatment of chronic wounds, as well as the advantages and the mechanism of ADSCs in promoting the healing of chronic wounds, to provide a reference for the stem cell therapy of chronic wounds.

Cancer cells as a new source of induced pluripotent stem cells

Over the last 2 decades, induced pluripotent stem cells (iPSCs) have had various potential applications in various medical research areas, from personalized medicine to disease treatment. Different cellular resources are accessible for iPSC generation, such as keratinocytes, skin fibroblasts, and blood or urine cells. However, all these sources are somatic cells, and we must make several changes in a somatic cell's transcriptome and chromatin state to become a pluripotent cell. It has recently been revealed that cancer cells can be a new source of iPSCs production. Cancer cells show similarities with iPSCs in self-renewal capacity, reprogramming potency, and signaling pathways. Although genetic abnormalities and potential tumor formation in cancer cells pose a severe risk, reprogrammed cancer-induced pluripotent stem cells (cancer-iPSCs) indicate that pluripotency can transiently overcome the cancer phenotype. This review discusses whether cancer cells can be a preferable source to generate iPSCs.