Treatment with adipose tissue-derived mesenchymal stem cells exerts anti-diabetic effects, improves long-term complications, and attenuates inflammation in type 2 diabetic rats. Stem Cell Res Ther. 2019;10:333. [PMID: 31747961 PMCID: PMC6868748 DOI: 10.1186/s13287-019-1474-8]

Human Adipose Tissue-Derived Stromal Cells Ameliorate Adriamycin-Induced Nephropathy by Promoting Angiogenesis

This study is to investigate the therapeutical effect and mechanisms of human-derived adipose mesenchymal stem cells (ADSC) in relieving adriamycin (ADR)-induced nephropathy (AN). SD rats were separated into normal group, ADR group, ADR+Losartan group (20 mg/kg), and ADR + ADSC group. AN rats were induced by intravenous injection with adriamycin (8 mg/kg), and 4 d later, ADSC (2 × 105 cells/mouse) were administrated twice with 2 weeks interval time (i.v.). The rats were euthanized after the 6 weeks' treatment. Biochemical indicators reflecting renal injury, such as blood urea nitrogen (BUN), neutrophil gelatinase alpha (NGAL), serum creatinine (Scr), inflammation, oxidative stress, and pro-fibrosis molecules, were evaluated. Results demonstrated that we obtained high qualified ADSCs for treatment determined by flow cytometry, and ADSCs treatment significantly ameliorated renal injuries in DN rats by decreasing BUN, Scr and NGAL in peripheral blood, as well as renal histopathological injuries, especially protecting the integrity of podocytes by immunofluorescence. Furthermore, ADSCs treatment also remarkably reduced the renal inflammation, oxidative stress, and fibrosis in DN rats. Preliminary mechanism study suggested that the ADSCs treatment significantly increased renal neovascularization via enhancing proangiogenic VEGF production. Pharmacodynamics study using in vivo imaging confirmed that ADSCs via intravenous injection could accumulate into the kidneys and be alive at least 2 weeks. In a conclusion, ADSC can significantly alleviate ADR-induced nephropathy, and mainly through reducing oxidative stress, inflammation and fibrosis, as well as enhancing VEGF production.

The Effect of Exercise on Mesenchymal Stem Cells and their Application in Obesity Treatment

Mesenchymal stem cells (MSCs) have demonstrated considerable potential in tissue repair and the treatment of immune-related diseases, but there are problems with homing efficiency during MSCs transplantation. Exercise, as an intervention, has been shown to have an important impact on the properties of MSCs. This review summarizes the effects of exercise on the properties (including proliferation, apoptosis, differentiation, and homing) of bone marrow-derived MSCs and adipose-derived MSCs. Studies indicated that exercise enhances bone marrow-derived MSCs proliferation, osteogenic differentiation, and homing while reducing adipogenic differentiation. For adipose-derived MSCs, exercise enhances proliferation and reduces adipogenic differentiation. In addition, studies have investigated the therapeutic effects of combined therapy of MSCs transplantation with exercise on diseases of the bone, cardiac, and nervous systems. The combined therapy improves tissue repair by increasing the homing of transplanted MSCs and cytokine secretion (such as neurotrophin 4). Furthermore, MSCs transplantation also has potential for the treatment of obesity. Although the effect is not significant in weight loss, MSCs transplantation shows effects in controlling blood glucose, improving dyslipidemia, reducing inflammation, and improving liver disease. Finally, the potential role of combined MSCs transplantation and exercise therapy in addressing obesity is discussed.

Microarray analysis of tRNA-derived small RNA (tsRNA) in LPS-challenged macrophages treated with metformin

Metformin, a widely used anti-diabetic drug, has demonstrated its efficacy in addressing various inflammatory conditions. tRNA-derived small RNA (tsRNA), a novel type of small non-coding RNA, exhibits diverse regulatory functions and holds promise as both a diagnostic biomarker and a therapeutic target for various diseases. The purpose of this study is to investigate whether the abundance of tsRNAs changed in LPS versus LPS + metformin-treated cells, utilizing microarray technology. Firstly, we established an in vitro lipopolysaccharide (LPS)-induced inflammation model using RAW264.7 macrophages and assessed the protective effects of metformin against inflammatory damage. Subsequently, we extracted total RNA from both LPS-treated and metformin + LPS-treated cell samples for microarray analysis to identify differentially abundant tsRNAs (DA-tsRNAs). Furthermore, we conducted bioinformatics analysis to predict target genes for validated DA-tsRNAs and explore the biological functions and signaling pathways associated with DA-tsRNAs. Notably, metformin was found to inhibit the inflammatory response in RAW264.7 macrophages. The microarray results revealed a total of 247 DA-tsRNAs, with 58 upregulated and 189 downregulated tsRNAs in the Met + LPS group compared to the LPS group. The tsRNA-mRNA network was visualized, shedding light on potential interactions. The results of bioinformatics analysis suggested that these potential targets of specific tsRNAs were mainly related to inflammation and immunity. Our study provides compelling evidence that metformin exerts anti-inflammatory effects and modulates the abundance of tsRNAs in LPS-treated RAW264.7 macrophages. These findings establish a valuable foundation for using tsRNAs as potential biomarkers for metformin in the treatment of inflammatory conditions.

The impact of gut microbial dysbiosis on the atrophy of the hippocampus and abnormal metabolism of N-acetyl aspartate in type 2 diabetic rats

Rationale and objectives

This study aimed to investigate the effect of intestinal dysbiosis on the hippocampal volume using proton magnetic resonance spectroscopy (1H-MRS) in a type 2 diabetes mellitus (T2DM) rat model.

Materials and methods

We established a T2DM animal model with high-fat diet and streptozotocin (HFD/STZ) administration to Sprague-Dawley rats. Short-term ceftriaxone sodium administration was used to establish a T2DM intestinal dysbiosis (T2DM-ID) model. After establishing the model, fecal microbiota were detected using 16S rRNA sequencing. The models were then subjected to magnetic resonance imaging (MRI). Associations between MRI findings and fecal microbiota were evaluated.

Results

Magnetic resonance imaging (MRI) showed that the bilateral hippocampal voxel value and N-acetylaspartate (NAA) level were lower in the experimental group than in the normal control (NC) group (p < 0.05) and that NAA/creatine in the left hippocampus was lower in the T2DM-ID group than in the NC group (p < 0.05). α and β diversities differed significantly among the three groups (p < 0.05). In the T2DM and T2DM-ID groups, the abundance of bacteria in the phylum Proteobacteria increased significantly, whereas that of bacteria in the phylum Firmicutes decreased. The relative abundance of Actinobacteria was significantly increased in the T2DM-ID group. The Chao1 index (r = 0.33, p < 0.05) and relative abundance of Firmicutes (r = 0.48, p < 0.05) were positively correlated with the left hippocampal voxel, while the relative abundance of Proteobacteria was negatively correlated with the left hippocampal voxel (r = -0.44, p < 0.05). NAA levels, bilateral hippocampal voxels, and the relative abundance of Lactobacillus, Clostridia_UCG_014, and other genera were correlated positively (r = 0.34-0.70, p < 0.05). NAA levels and the relative abundances of Blautia and Enterococcus were correlated negatively (r = -0.32-0.44, p < 0.05).

Conclusion

The T2DM-ID rat model showed hippocampal volume atrophy and decreased levels of neuronal markers (such as NAA). The abnormal content of specific gut microorganisms may be a key biomarker of T2DM-associated brain damage.

Therapeutic potential: The role of mesenchymal stem cells from diverse sources and their derived exosomes in diabetic nephropathy

Diabetic nephropathy (DN) is one of the most common microvascular complications in diabetic patients, with its incidence continuously increasing in recent years. DN causes renal tissue damage and functional decline, expedites the aging process of the kidneys, and may ultimately progress leading to end-stage renal disease, severely impacting the patient's quality of life and prognosis. Mesenchymal stem cells (MSCs) are highly valued for their multipotent differentiation, paracrine functions, immunomodulatory effects, and capacity for tissue repair. Particularly, exosomes (Exo) derived from MSCs (MSCs-Exo) are rich in bioactive molecules and facilitate intercellular communication, participating in various physiological and pathological processes. MSCs and MSCs-Exo, in particular, have been demonstrated to have therapeutic effects in DN treatment research by encouraging tissue repair, fibrosis inhibition, and inflammation reduction. Research has shown that MSCs and MSCs-Exo have therapeutic effects in DN treatment by promoting tissue repair, inhibiting fibrosis, and reducing inflammation. Recent studies underscore the potential of MSCs and MSCs-Exo, highlighting their broad applicability in DN treatment. This review aims to provide a comprehensive summary of the scientific developments in treating DN using MSCs and MSCs-Exo from diverse sources, while also exploring their future therapeutic possibilities in detail.

Adipose-derived stem cells can alleviate RHDV2 induced acute liver injury in rabbits

Rabbit hemorrhagic disease virus (RHDV) can cause fatal fulminant hepatitis, which is very similar to human acute liver failure. The aim of this study was to investigate whether adipose-derived stem cells (ADSCs) could alleviate RHDV2-induced liver injury in rabbits. Twenty 50-day-old rabbits were divided randomly into two groups (RHDV2 group, ADSCs + RHDV2 group). Starting from the 1st day, two groups of rabbits were given 0.5 ml of viral suspensions by subcutaneous injection in the neck. Meanwhile, the ADSCs + RHDV2 group was injected with ADSCs cell suspension (1.5 × 107 cells/ml) via a marginal ear vein, and the RHDV2 group was injected with an equal amount of saline via a marginal ear vein. At the end of the 48 h experiment, the animals were euthanized and gross hepatic changes were observed before liver specimens were collected. Histopathological analysis was performed using hematoxylin-eosin (HE), periodic acid schiff (PAS) and Masson's trichrome staining. For RHDV2 affected rabbits, HE staining demonstrated disorganized hepatic cords, loss of cellular detail, and severe cytoplasmic vacuolation within hepatocytes. Glycogen was not observed with PAS staining, and Masson's Trichrome staining showed increased hepatic collagen deposition. For rabbits treated with ADSCs at the time of inoculation, hepatic pathological changes were significantly less severe, liver glycogen synthesis was increased, and collagen fiber deposition was decreased. For RHDV2 affected rabbits, Tunel and immunofluorescence staining showed that the number of apoptotic cells, TGF-β, and MMP-9 protein expression increased. And that in the ADSC treated group there was less hepatocyte apoptosis. In addition, RHDV2 induces liver inflammation and promotes the expression of IL-1β, IL-6, and TNF-α. In rabbits administered ADSCs at time of inoculation, the expression of inflammatory factors in liver tissue decreased significantly. Our experiments show that ADSCs can protect rabbits from liver injury by RHDV2 and reduce the pathological and inflammatory response of liver. However, the specific protective mechanism needs further study.

Mechanical stretch preconditioned adipose-derived stem cells elicit polarization of anti-inflammatory M2-like macrophages and improve chronic wound healing

Transplantation of adipose-derived stem cells (ASCs) is a promising option in the field of chronic wounds treatment. However, the effectiveness of ASCs therapies has been hampered by highly inflammatory environment in chronic wound areas. These problems could be partially circumvented using efficient approaches that boost the survival and anti-inflammatory capacity of transplanted ASCs. Here, by application of mechanical stretch (MS), we show that ASCs exhibits increased survival and immunoregulatory properties in vitro. MS triggers the secretion of macrophage colony stimulating factor (M-CSF) from ASCs, a chemokine that is linked to anti-inflammatory M2-like macrophages polarization. When the MS-ASCs were transplanted to chronic wounds, the wound area yields significantly faster closure rate and lower inflammatory mediators, largely due to macrophages polarization driven by transplanted MS-ASCs. Thus, our work shows that mechanical stretch can be harnessed to enhance ASCs transplantation efficiency in chronic wounds treatment.

Human Umbilical Cord Mesenchymal Stem Cells Promote Anti-Inflammation and Angiogenesis by Targeting Macrophages in a Rat Uterine Scar Model

BACKGROUND

Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have demonstrated efficacy in repairing uterine scars, although the underlying mechanisms remain unclear.

METHODS

Uterine injury was surgically induced in a rat model, followed by immediate transplantation of 5 × 10 ^ 5 hUC-MSCs to each side of the uterus. Uterine morphology was evaluated at days 14 and 30 using HE and Masson staining. Immunohistochemistry assessed macrophage polarization, angiogenesis and endometrial receptivity in the endometrium. Additionally, the regulatory effects of hUC-MSCs on macrophage polarization were explored through coculture. qRT-PCR quantified the expression of anti-inflammatory (IL10 and Arg1) and pro-inflammatory (iNOS and TNF-α) factors. Western blotting evaluated CD163 expression.

RESULTS

Transplantation of hUC-MSCs promoted the healing of uterine injuries and tissue regeneration while inhibiting tissue fibrosis. Immunohistochemistry at days 14 and 30 post-transplantation demonstrated the polarization of macrophages toward the M2 phenotype in the uterine injury area in the presence of hUC-MSCs. Furthermore, hUC-MSC transplantation improved angiogenesis and endometrial receptivity in the uterine injury rat model, associated with increased IL10 expression. hUC-MSC-induced angiogenesis can be resisted by depleted macrophages. In vitro coculture experiments further demonstrated that hUC-MSCs promoted IL10 expression in macrophages while suppressing TNF-α and iNOS expression. Western blotting showed enhanced CD163 expression in macrophages following hUC-MSC treatment.

CONCLUSIONS

hUC-MSCs contribute to the healing of uterine injuries by targeting macrophages to promote angiogenesis and the expression of anti-inflammatory factors.

Pathophysiological Features of Rat Models of Nonalcoholic Fatty Liver Disease/Nonalcoholic Steatohepatitis

Nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) is caused by various factors, including genetic and/or environmental factors, and has complicated pathophysiological features during the development of the disease. NAFLD/NASH is recognized as an unmet medical need, and NAFLD/NASH animal models are essential tools for developing new therapies, including potential drugs and biomarkers. In this review, we describe the pathological features of the NAFLD/NASH rat models, focusing on the histopathology of hepatic fibrosis. NAFLD/NASH rat models are divided into three categories: diet-induced, genetic, and combined models based on diet, chemicals, and genetics. Rat models of NASH with hepatic fibrosis are especially expected to contribute to the development of new therapies, such as drugs and biomarkers.

Influence of blood glucose fluctuations on chemotherapy efficacy and safety in type 2 diabetes mellitus patients complicated with lung carcinoma

BACKGROUND

Patients with type 2 diabetes mellitus (T2DM) have large fluctuations in blood glucose (BG), abnormal metabolic function and low immunity to varying degrees, which increases the risk of malignant tumor diseases and affects the efficacy of tumor chemotherapy. Controlling hyperglycemia may have important therapeutic implications for cancer patients.

AIM

To clarify the influence of BG fluctuations on chemotherapy efficacy and safety in T2DM patients complicated with lung carcinoma (LC).

METHODS

The clinical data of 60 T2DM + LC patients who presented to the First Affiliated Hospital of Ningbo University between January 2019 and January 2021 were retrospectively analyzed. All patients underwent chemotherapy and were grouped as a control group (CG; normal BG fluctuation with a mean fluctuation < 3.9 mmol/L) and an observation group (OG; high BG fluctuation with a mean fluctuation ≥ 3.9 mmol/L) based on their BG fluctuations, with 30 cases each. BG-related indices, tumor markers, serum inflammatory cytokines and adverse reactions were comparatively analyzed. Pearson correlation analysis was performed to analyze the correlation between BG fluctuations and tumor markers.

RESULTS

The fasting blood glucose and 2-hour postprandial blood glucose levels in the OG were notably elevated compared with those in the CG, together with markedly higher mean amplitude of glycemic excursions (MAGE), mean of daily differences, largest amplitude of glycemic excursions and standard deviation of blood glucose (P < 0.05). In addition, the OG exhibited evidently higher levels of carbohydrate antigen 19-9, carbohydrate antigen 125, carcinoembryonic antigen, neuron-specific enolase, cytokeratin 19, tumor necrosis factor-α, interleukin-6, and high-sensitivity C-reactive protein than the CG (P < 0.05). Pearson analysis revealed a positive association of MAGE with serum tumor markers. The incidence of adverse reactions was significantly higher in the OG than in the CG (P < 0.05).

CONCLUSION

The greater the BG fluctuation in LC patients after chemotherapy, the more unfavorable the therapeutic effect of chemotherapy; the higher the level of tumor markers and inflammatory cytokines, the more adverse reactions the patient experiences.

Alleviation of taurine on liver injury of type 2 diabetic rats by improving antioxidant and anti-inflammatory capacity

Type 2 diabetes mellitus (T2DM) is a serious metabolic disease characterized by insulin resistance and reduced insulin production, which causes abnormally elevated blood glucose. It has been reported that T2DM can enhance oxidative stress and inflammatory responses, and stimulate a variety of complications including liver injury. Studies have shown that taurine has antioxidant and anti-inflammatory effects that can not only ameliorate diabetes but also alleviate liver injury caused by various diseases. However, its effect on liver injury in T2DM is not clear. In our study, a high-fat diet and intraperitoneal injection of streptozotocin (STZ) was used to induce liver injury in T2DM rats, and taurine was given as a treatment. Through the use of HE staining on paraffin sections, ELISA, and qRT-PCR, the effects of taurine on liver pathological alterations, antioxidant capacity, and inflammatory response were investigated. We found that: hepatic transaminase levels of rats were reduced significantly following taurine administration; histopathological observations revealed that the morphology of rat hepatocytes was close to normal, and the number of inflammatory cells around liver vessels was significantly reduced; antioxidant-related indicators were significantly increased, including SOD, CAT, GSH-Px and T-AOC, while related factors of the Nrf2 signalling pathway and its downstream HO-1, NQO1 and γ-GCS were significantly increased; the expression of the JAK2-STAT1 signalling pathway, TLR4/NF-κB signalling pathway and NLRP3 inflammatory vesicle-related factors were significantly reduced. Our results suggest taurine can alleviate T2DM-induced liver injury by improving the antioxidant capacity of the liver and inhibiting macrophage M1-type polarization and the inflammatory response mediated thereby.

Oxidative Stress: A Culprit in the Progression of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the principal culprit behind chronic kidney disease (CKD), ultimately developing end-stage renal disease (ESRD) and necessitating costly dialysis or kidney transplantation. The limited therapeutic efficiency among individuals with DKD is a result of our finite understanding of its pathogenesis. DKD is the result of complex interactions between various factors. Oxidative stress is a fundamental factor that can establish a link between hyperglycemia and the vascular complications frequently encountered in diabetes, particularly DKD. It is crucial to recognize the essential and integral role of oxidative stress in the development of diabetic vascular complications, particularly DKD. Hyperglycemia is the primary culprit that can trigger an upsurge in the production of reactive oxygen species (ROS), ultimately sparking oxidative stress. The main endogenous sources of ROS include mitochondrial ROS production, NADPH oxidases (Nox), uncoupled endothelial nitric oxide synthase (eNOS), xanthine oxidase (XO), cytochrome P450 (CYP450), and lipoxygenase. Under persistent high glucose levels, immune cells, the complement system, advanced glycation end products (AGEs), protein kinase C (PKC), polyol pathway, and the hexosamine pathway are activated. Consequently, the oxidant-antioxidant balance within the body is disrupted, which triggers a series of reactions in various downstream pathways, including phosphoinositide 3-kinase/protein kinase B (PI3K/Akt), transforming growth factor beta/p38-mitogen-activated protein kinase (TGF-β/p38-MAPK), nuclear factor kappa B (NF-κB), adenosine monophosphate-activated protein kinase (AMPK), and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling. The disease might persist even if strict glucose control is achieved, which can be attributed to epigenetic modifications. The treatment of DKD remains an unresolved issue. Therefore, reducing ROS is an intriguing therapeutic target. The clinical trials have shown that bardoxolone methyl, a nuclear factor erythroid 2-related factor 2 (Nrf2) activator, blood glucose-lowering drugs, such as sodium-glucose cotransporter 2 inhibitors, and glucagon-like peptide-1 receptor agonists can effectively slow down the progression of DKD by reducing oxidative stress. Other antioxidants, including vitamins, lipoic acid, Nox inhibitors, epigenetic regulators, and complement inhibitors, present a promising therapeutic option for the treatment of DKD. In this review, we conduct a thorough assessment of both preclinical studies and current findings from clinical studies that focus on targeted interventions aimed at manipulating these pathways. We aim to provide a comprehensive overview of the current state of research in this area and identify key areas for future exploration.

ATP releasing channels and the ameliorative effects of high intensity interval training on diabetic heart: a multifaceted analysis

Type 2 diabetes (T2D) can cause severe cardiac complications at functional, histologic and molecular levels. These pathological complications could be mediated by ATP-releasing channels such as Panx1 and ATP receptors, in particular P2X7. The aim of our study was to investigate the effect of high-intensity interval training (HIIT) on T2D-induced cardiac complications at the functional, histopathological and molecular levels, with a particular focus on ATP-releasing channels. 48 male Wistar rats at the age of 8 weeks were randomly allocated into four groups: control (Con), Diabetes (T2D), Training (TR), and Diabetes + Training (T2D + TR). T2D was induced by a high-fat diet plus a low dose (35 mg/kg) of STZ administration. Rats in the TR and T2D + TR groups underwent an 8-weeks training program involving intervals ranging from 80 to 100% of their maximum running speed (Vmax), with 4-10 intervals per session. Protein expression of Interleukin 1β (IL1β), Interleukin 10 (IL-10), Pannexin 1 (Panx1), P2X7R (purinergic P2X receptor 7), NLRP1 (NLR Family Pyrin Domain Containing 1), BAX, and Bcl2 were measured in the heart tissue. Additionally, we assessed heart function, histopathological changes, as well as insulin resistance using the homeostasis model assessment of insulin resistance (HOMA-IR). In contrast to the T2D group, HIIT led to increased protein expression of Bcl2 and IL-10 in the heart. It also resulted in improvements in systolic and diastolic blood pressures, heart rate, ± dp/dt (maximum and minimum changes in left ventricular pressure), while reducing protein expression of IL-1β, Panx1, P2X7R, NLRP1, and BAX levels in the heart. Furthermore, left ventricular diastolic pressure (LVDP) was reduced (P ≤ 0.05). Moreover, heart lesion scores increased with T2D but decreased with HIIT, along with a reduction in fibrosis percentage (P ≤ 0.05). The results of this study suggest that the cardioprotective effects of HIIT on the diabetic heart may be mediated by the modulation of ATP-releasing channels. This modulation may lead to a reduction in inflammation and apoptosis, improve cardiac function, and attenuate cardiac injury and fibrosis.

The phenotype and related gene expressions of macrophages in adipose tissue of T2D mice following MSCs infusion

BACKGROUND

Infusion of mesenchymal stem cells (MSCs) induces polarization of M2 macrophages in adipose tissue of type 2 diabetes (T2D) mice. Studies have shown that M2 macrophages were divided into four sub-phenotypes (M2a, M2b, M2c and M2d) with different functions, and manuscripts have also confirmed that macrophages co-cultured with MSCs were not matched with known four phenotype macrophages. Therefore, our study explored the phenotype and related gene expressions of macrophages in the adipose tissue of T2D mice with/without MSCs infusion.

METHODS

We induced a T2D mouse model by using high-fat diets and streptozotocin (STZ) injection. The mice were divided into three groups: the control group, the T2D group, and the MSCs group. MSCs were systemically injected once a week for 6 weeks. The phenotype of macrophages in adipose tissue was detected via flow cytometric analysis. We also investigated the gene expression of macrophages in different groups via SMART-RNA-sequencing and quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR).

RESULTS

The present study found that the macrophages of adipose tissue in the MSCs group were polarized to the M2 phenotype mixed with four sub-phenotypes. Besides, M2a and M2c held a dominant position, while M2b and M2d (tumor-associated macrophages, TAMs) exhibited a decreasing trend after infusion of MSCs. Moreover, the MSCs group did not appear to express higher levels of tumor-associated, inflammation-associated, or fibrosis-associated genes in comparison to the T2D group.

CONCLUSION

The present results unveiled that the macrophage phenotype was inclined to be present in a hybridity state of four M2 sub-phenotypes and the genes related to tumor-promoting, pro-inflammation and pro-fibrosis were not increased after MSCs injection.

Effects of adipose-derived mesenchymal stem cell conditioned medium on human tenocytes exposed to high glucose

Introduction

Diabetic tendinopathy is a common invalidating and challenging disease that may be treated using stem cells. However, the effects of adipose-derived mesenchymal stem cell conditioned medium (ASC-CM) in diabetic tendinopathy have never been explored.

Objectives

The present study evaluated the effects of ASC-CM on morphology, cell viability, structure, and scratch wound closure of human tenocytes (HTNC) exposed to high glucose (HG).

Design

Experimental study.

Methods

HTNC were exposed to HG (25 mM) for 7, 14 and 21 days with or without ASC-CM for the last 24 h. CM was collected from 4 × 105 ASCs, centrifuged for 10 min at 200 g and sterilized with 0.22 μm syringe filter.

Results

At 7 days, HG-HTNC had decreased cell viability [72 ± 2%, p < 0.01 versus normal glucose (NG)] compared to NG-HTNC (90 ± 5%). A further decrement was detected after 14 and 21 days (60 ± 4% and 60 ± 5%, both, p < 0.01 versus NG and p < 0.01 versus HG7). While NG-HTNC evidenced a normal fibroblast cell-like elongated morphology, HG-HTNC showed increased cell roundness. In contrast, HG-HTNC exposed to ASC-CM showed a significant increase in cell viability, an improved cell morphology and higher scratch wound closure at all HG time points. Moreover, the exposure to ASC-CM significantly increased thrombospondin 1 and transforming growth factor beta 1 (TGF-β1) content in HG-HTNC. The TGF-β1 elevation was paralleled by higher Collagen I and Vascular Endothelial Growth Factor in HG-HTNC.

Conclusion

ASC-CM may restore the natural morphology, cell viability and structure of HTNC, promoting their scratch wound closure through TGF-β1 increase.

Progress and application of adipose-derived stem cells in the treatment of diabetes and its complications

Diabetes mellitus (DM) is a serious chronic metabolic disease that can lead to many serious complications, such as cardiovascular disease, retinopathy, neuropathy, and kidney disease. Once diagnosed with diabetes, patients need to take oral hypoglycemic drugs or use insulin to control blood sugar and slow down the progression of the disease. This has a significant impact on the daily life of patients, requiring constant monitoring of the side effects of medication. It also imposes a heavy financial burden on individuals, their families, and even society as a whole. Adipose-derived stem cells (ADSCs) have recently become an emerging therapeutic modality for DM and its complications. ADSCs can improve insulin sensitivity and enhance insulin secretion through various pathways, thereby alleviating diabetes and its complications. Additionally, ADSCs can promote tissue regeneration, inhibit inflammatory reactions, and reduce tissue damage and cell apoptosis. The potential mechanisms of ADSC therapy for DM and its complications are numerous, and its extensive regenerative and differentiation ability, as well as its role in regulating the immune system and metabolic function, make it a powerful tool in the treatment of DM. Although this technology is still in the early stages, many studies have already proven its safety and effectiveness, providing new treatment options for patients with DM or its complications. Although based on current research, ADSCs have achieved some results in animal experiments and clinical trials for the treatment of DM, further clinical trials are still needed before they can be applied in a clinical setting.

GRP78 improves the therapeutic effect of mesenchymal stem cells on hemorrhagic shock-induced liver injury: Involvement of the NF-кB and HO-1/Nrf-2 pathways

Mesenchymal stem cells (MSCs) are a popular cell source for repairing the liver. Improving the survival rate and colonization time of MSCs may significantly improve the therapeutic outcomes of MSCs. Studies showed that 78-kDa glucose-regulated protein (GRP78) expression improves cell viability and migration. This study aims to examine whether GRP78 overexpression improves the efficacy of rat bone marrow-derived MSCs (rBMSCs) in HS-induced liver damage. Bone marrow was isolated from the femurs and tibias of rats. rBMSCs were transfected with a GFP-labeled GRP78 expression vector. Flow cytometry, transwell invasion assay, scratch assay immunoblotting, TUNEL assay, MTT assay, and ELISA were carried out. The results showed that GRP78 overexpression enhanced the migration and invasion of rBMSCs. Moreover, GRP78-overexpressing rBMSCs relieved liver damage, repressed liver oxidative stress, and inhibited apoptosis. We found that overexpression of GRP78 in rBMSCs inhibited activation of the NLRP3 inflammasome, significantly decreased the levels of inflammatory factors, and decreased the expression of CD68. Notably, GRP78 overexpression activated the Nrf-2/HO-1 pathway and inhibited the NF-κB pathway. High expression of GRP78 efficiently enhanced the effect of rBMSC therapy. GRP78 may be a potential target to improve the therapeutic efficacy of BMSCs.

Therapeutic potential of stem cells in regeneration of liver in chronic liver diseases: Current perspectives and future challenges

The deposition of extracellular matrix and hyperplasia of connective tissue characterizes chronic liver disease called hepatic fibrosis. Progression of hepatic fibrosis may lead to hepatocellular carcinoma. At this stage, only liver transplantation is a viable option. However, the number of possible liver donors is less than the number of patients needing transplantation. Consequently, alternative cell therapies based on non-stem cells (e.g., fibroblasts, chondrocytes, keratinocytes, and hepatocytes) therapy may be able to postpone hepatic disease, but they are often ineffective. Thus, novel stem cell-based therapeutics might be potentially important cutting-edge approaches for treating liver diseases and reducing patient' suffering. Several signaling pathways provide targets for stem cell interventions. These include pathways such as TGF-β, STAT3/BCL-2, NADPH oxidase, Raf/MEK/ERK, Notch, and Wnt/β-catenin. Moreover, mesenchymal stem cells (MSCs) stimulate interleukin (IL)-10, which inhibits T-cells and converts M1 macrophages into M2 macrophages, producing an anti-inflammatory environment. Furthermore, it inhibits the action of CD4+ and CD8+ T cells and reduces the activity of TNF-α and interferon cytokines by enhancing IL-4 synthesis. Consequently, the immunomodulatory and anti-inflammatory capabilities of MSCs make them an attractive therapeutic approach. Importantly, MSCs can inhibit the activation of hepatic stellate cells, causing their apoptosis and subsequent promotion of hepatocyte proliferation, thereby replacing dead hepatocytes and reducing liver fibrosis. This review discusses the multidimensional therapeutic role of stem cells as cell-based therapeutics in liver fibrosis.

Treatment of type 2 diabetes mellitus with stem cells and antidiabetic drugs: a dualistic and future-focused approach

Type 2 Diabetes Mellitus (T2DM) accounts for more than 90% of total diabetes mellitus cases all over the world. Obesity and lack of balance between energy intake and energy expenditure are closely linked to T2DM. Initial pharmaceutical treatment and lifestyle interventions can at times lead to remission but usually help alleviate it to a certain extent and the condition remains, thus, recurrent with the patient being permanently pharmaco-dependent. Mesenchymal stromal cells (MSCs) are multipotent, self-renewing cells with the ability to secrete a variety of biological factors that can help restore and repair injured tissues. MSC-derived exosomes possess these properties of the original stem cells and are potentially able to confer superior effects due to advanced cell-to-cell signaling and the presence of stem cell-specific miRNAs. On the other hand, the repository of antidiabetic agents is constantly updated with novel T2DM disease-modifying drugs, with higher efficacy and increasingly convenient delivery protocols. Delving deeply, this review details the latest progress and ongoing studies related to the amalgamation of stem cells and antidiabetic drugs, establishing how this harmonized approach can exert superior effects in the management and potential reversal of T2DM.

Tetrahedral Framework Nucleic Acids Based Small Interfering RNA Targeting Receptor for Advanced Glycation End Products for Diabetic Complications Treatment

Complications arising from diabetes can threaten multiple organs. Advanced glycation end products (AGEs) play a significant role in inducing these complications. Highly processed diets and hyperglycemia facilitate the accumulation of AGEs in the body. Interaction between AGEs and their main receptor (RAGE) initiates the transmission of intracellular inflammatory and cell death signals, which ultimately lead to complications. To counter AGEs-induced damage, we developed an siRNA-binding tetrahedral framework nucleic acids (TDN) system, termed Tsi, which combines the potent cell membrane penetrability and serum stability of TDN with the gene-targeting specificity of siRNA-RAGE. Tsi effectively and persistently downregulates the expression of RAGE, thereby suppressing inflammation by blocking the NF-κB pathway as well as exhibiting antioxidant functions. Furthermore, Tsi regulates the pyroptosis state of macrophages via the NLRP3/caspase-1 axis, which inhibits the spread of cell death signals and maintains homeostasis. This is of great significance for the synergistic treatment strategy for systemic complications in patients with refractory hyperglycemia. In summary, this study describes a nanomedicine that targets the RAGE and suppresses AGE-induced inflammation. This nucleic acid drug holds long-lasting efficacy and is independent of lowering hyperglycemia, which provides a strategy for the treatment of diabetic complications and age-related diseases.

A crossroads between dietary habits, alcohol consumption, and smoking in the clinical course of psoriasis: a narrative review

Psoriasis is a chronic autoimmune disease that affects 1-3% of the population. The pathomechanism of psoriasis development is complex, but genetic (non-modifiable) factors play a key role. However, the importance of environmental factors and lifestyle choices, such as the diet, alcohol consumption, and smoking, is increasing. The objective of this review was to analyse the influence of dietary habits, alcohol consumption, and smoking on the clinical course of psoriasis. Stress, a poor diet, alcohol abuse, and smoking can trigger psoriasis or cause its exacerbation. Therefore, in addition to the correct selection of therapy, it is extremely important to educate patients about the impact of these factors on the onset and progression of psoriasis. This literature review confirms that a holistic and multidisciplinary approach is required for patients with psoriasis, further emphasizing Hippocrates' thesis, "Let food be thy medicine, and medicine be thy food".

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.

Transplantation of insulin-producing cells derived from human MSCs to treat diabetes in a non-human primate model

BACKGROUND

Islet cell transplantation is an emerging therapy in the treatment of diabetes mellitus. Differentiation of islet cells from mesenchymal stem cells (MSCs) is a potential solution to the challenge of insufficient donor sources. This study investigated whether human umbilical cord-derived MSCs could effectively differentiate into insulin-producing cells (IPCs) and evaluated the therapeutic efficacy of IPCs in treating diabetes.

METHODS

IPCs were induced from MSCs by a two-step protocol. IPC expression products were evaluated by western blot and real-time PCR. IPC insulin secretion was evaluated by ELISA. The viability of IPCs was measured by FDA/PI and dithizone staining. The non-human primate tree shrew was used as a diabetes model. After a single STZ induction into a diabetes model, a single intraportal transplantation of IPCs, MSCs, or normal saline was performed (n = 6 per group). Blood glucose was monitored for 3 weeks, then the animals were euthanized and the distribution of IPCs in the liver was examined pathologically.

RESULTS

After about 3 weeks of in vitro induction, IPCs formed microspheres of 100-200 μm, with >95% viable cells that were dithizone stain positive. IPCs expressed islet-related genes and proteins and secreted high levels of insulin whether stimulated by low or high levels of glucose. After transplantation of IPCs into diabetic tree shrews, blood glucose levels decreased rapidly to near normal and were significantly lower than the MSC or saline groups for 3 weeks thereafter.

CONCLUSION

We present the novel discovery that IPCs derived from human umbilical cord MSCs exert a therapeutic effect in a non-human primate model of diabetes. This study provides a preliminary experimental basis for the use of autologous MSC-derived IPCs in the treatment of human diabetes.

Ticlopidine induces embryonic development toxicity and hepatotoxicity in zebrafish by upregulating the oxidative stress signaling pathway

Ticlopidine exerts its anti-platelet effects mainly by antagonizing platelet p2y12 receptors. Previously, a few studies have shown that ticlopidine can induce liver injury, but the exact mechanism of hepatotoxicity remains unclear. Oxidative stress, metabolic disorders, hepatocyte apoptosis, lipid peroxidation, and inflammatory responses can all lead to hepatic liver damage, which can cause hepatotoxicity. In this study, in order to deeply explore the potential molecular mechanisms of ticlopidine -induced hepatotoxicity, we used zebrafish as a model organism to comprehensively evaluate the hepatotoxicity of ticlopidine and its associated mechanism. Three days post-fertilization, zebrafish larvae were exposed to varying concentrations (1.5, 1.75 and 2 μg/mL) of ticlopidine for 72 h, in contrast, adult zebrafish were exposed exposure to 4 μg/mL of ticlopidine for 28 days. Ticlopidine-exposed zebrafish larvae showed changes in liver morphology, shortened body length, and delayed development of the swim bladder development. Liver tissues of ticlopidine-exposed zebrafish larvae and adults stained with Hematoxylin & Eosin revealed vacuolization and increased cellular interstitial spaces in liver tissues. Furthermore, using Oil Red O and periodic acid-Schiff staining methods and evaluating different metabolic enzymes of ticlopidine-exposed zebrafish larvae and adults suggested abnormal liver metabolism and liver injury in both ticlopidine-exposed zebrafish larvae and adults. Ticlopidine also significantly elevated inflammation and oxidative stress and reduced hepatocyte proliferation. During the rescue intervention using N-acetylcysteine, we observed significant improvement in ticlopidine-induced morphological changes in the liver, shortened body length, delayed swim bladder development, and proliferation of liver tissues showed significant improvement. In conclusion, ticlopidine might inhibit normal development and liver proliferation in zebrafish by upregulation of oxidative stress levels, thus leading to embryonic developmental toxicity and hepatotoxicity. In this study, we used zebrafish as a model organism to elucidate the developmental toxicity and hepatotoxicity induced by ticlopidine upregulation of oxidative stress signaling pathway in zebrafish, providing a theoretical basis for clinical application.

Adipose-derived Mesenchymal Stem Cells Therapy as a new Treatment Option for Diabetes Mellitus

The worldwide increase in the prevalence of diabetes mellitus has raised the demand for new therapeutic strategies targeting diabetic symptoms and its chronic complications. Among different treatment options for diabetes, adipose-derived mesenchymal stem cells (ADMSCs) therapy attract the most attention. The therapeutic effects of ADMSCs are based primarily on their paracrine release of immunomodulatory, anti-inflammatory, and trophic factors. Animal models of diabetes as well as human clinical trials have shown that ADMSCs can effectively facilitate endogenous β cell regeneration, preserve residual β cell mass, reduce islet graft rejection, regulate the immune system, and ultimately improve insulin sensitivity or ameliorate insulin resistance in peripheral tissues. Nevertheless, transplantation of mesenchymal stem cells is associated with certain risks; therefore recently much attention has been devoted to ADMSCs derivatives, such as exosomes or conditioned media, as therapeutic agents for the treatment of diabetes. Compared to ADMSCs, cell-free therapy has even better therapeutic potential. This narrative review summarizes recent outcomes and molecular mechanisms of ADMSCs action in the treatment for both type 1 DM and type 2 DM, as well as shows their feasibility, benefits, and current limitations.

Awareness of Stem Cell Therapy for Diabetes Among Type II Diabetic Patients in Makkah: A Cross-Sectional Study

Background Diabetes mellitus is a chronic disease that affects millions of people worldwide. Several studies have suggested using stem cells for diabetes treatment. However, there is a lack of research assessing the population's awareness of stem cells. This study aimed to evaluate the level of awareness regarding the use of stem cell therapy for type 2 diabetes mellitus (T2DM). Methodology This study was conducted from December 2021 to April 2022 through an online survey that was distributed electronically via social media platforms. T2DM patients or their care providers who lived in Makkah were included. Patients aged less than 18 years and those with mental disabilities were excluded. Results Of the 316 participants included in the study, 56% were males, 33% had an age range of 46-55 years, and 76% were married. T2DM patients and their caregivers had a moderate level of awareness about stem cell therapy, with caregivers having higher awareness than diabetic patients. A non-significant relationship was found between educational level, income, diabetes control, time of diagnosis, and patients' awareness. However, regarding the decision of treatment, participants aged less than 35 years were highly likely to decide to undergo stem cell treatment compared to other age groups. Conclusions There is a moderate level of awareness about stem cell therapy as a treatment option for T2DM among T2DM patients and caregivers in Makkah. Hence, there is a need to raise awareness by using online and in-person well-organized education programs in Makkah.

Mechanism of immune attack in the progression of obesity-related type 2 diabetes

Obesity and overweight are widespread issues in adults, children, and adolescents globally, and have caused a noticeable rise in obesity-related complications such as type 2 diabetes mellitus (T2DM). Chronic low-grade inflammation is an important promotor of the pathogenesis of obesity-related T2DM. This proinflammatory activation occurs in multiple organs and tissues. Immune cell-mediated systemic attack is considered to contribute strongly to impaired insulin secretion, insulin resistance, and other metabolic disorders. This review focused on highlighting recent advances and underlying mechanisms of immune cell infiltration and inflammatory responses in the gut, islet, and insulin-targeting organs (adipose tissue, liver, skeletal muscle) in obesity-related T2DM. There is current evidence that both the innate and adaptive immune systems contribute to the development of obesity and T2DM.

Hypoxia activates the PI3K/AKT/HIF-1α pathway to promote the anti-inflammatory effect of adipose mesenchymal stem cells

This study aimed to investigate the effect of hypoxia on the anti-inflammatory effect of adipose-derived mesenchymal stem cells (AMSCs) in vitro and its possible mechanism. AMSCs were cultured in vitro in a hypoxic environment with 3% O₂, and a normoxic (21% O₂) environment was used as the control. The cells were identified by in vitro adipogenic and osteogenic differentiation and cell surface antigen detection, and the cell viability were detected. The effect of hypoxic AMSCs on macrophage inflammation was analyzed by co-culture. The results showed that under hypoxia, AMSCs had better viability, significantly downregulated the expression of inflammatory factors, alleviated macrophage inflammation, and activated the PI3K/AKT/HIF-1α pathway.

Gene Therapy Based on Mesenchymal Stem Cells Derived from Adipose Tissue for the Treatment of Obesity and Its Metabolic Complications

Obesity is a highly prevalent condition often associated with dysfunctional adipose tissue. Stem cell-based therapies have become a promising tool for therapeutic intervention in the context of regenerative medicine. Among all stem cells, adipose-derived mesenchymal stem cells (ADMSCs) are the most easily obtained, have immunomodulatory properties, show great ex vivo expansion capacity and differentiation to other cell types, and release a wide variety of angiogenic factors and bioactive molecules, such as growth factors and adipokines. However, despite the positive results obtained in some pre-clinical studies, the actual clinical efficacy of ADMSCs still remains controversial. Transplanted ADMSCs present a meager rate of survival and proliferation, possibly because of the damaged microenvironment of the affected tissues. Therefore, there is a need for novel approaches to generate more functional ADMSCs with enhanced therapeutic potential. In this context, genetic manipulation has emerged as a promising strategy. In the current review, we aim to summarize several adipose-focused treatments of obesity, including cell therapy and gene therapy. Particular emphasis will be given to the continuum from obesity to metabolic syndrome, diabetes, and underlying non-alcoholic fatty liver disease (NAFLD). Furthermore, we will provide insights into the potential shared adipocentric mechanisms involved in these pathophysiological processes and their remediation using ADMSCs.

Human adipose-derived mesenchymal stem cells-based microspheres ameliorate atherosclerosis progression in vitro

Atherosclerosis (AS) is a chronic inflammatory disease associated with lipids deposition which could be converted into acute clinical events by thrombosis or plaque rupture. Adipose-derived mesenchymal stem cells (ADSCs) encapsulated repair units could be an effective cure for the treatment of AS patients. Here, we encapsulate human ADSCs in collagen microspheres to fabricate stem cell repair units. Besides, we show that encapsulation in collagen microspheres and cultured in vitro for 14 days maintain the viability and stemness of human ADSCs. Moreover, we generate AS progression model and niche in vitro by combining hyperlipemia serum of AS patients with AS cell models. We further systematically demonstrate that human ADSCs-based microspheres could ameliorate AS progression by inhibiting oxidative stress injure, cell apoptosis, endothelial dysfunction, inflammation, and lipid accumulation. In addition, we perform transcriptomic analysis and functional studies to demonstrate how human ADSCs (3D cultured in microspheres) respond to AS niche compared with healthy microenvironment. These findings reveal a role for ADSCs-based microspheres in the treatment of AS and provide new ideas for stem cell therapy in cardiovascular disease. The results may have implications for improving the efficiency of human ADSC therapies by illuminating the mechanisms of human ADSCs exposed in special pathological niche.

Targeting inflammation to treat diabetic kidney disease: the road to 2030

Diabetic kidney disease (DKD) is one of the fastest growing causes of chronic kidney disease and associated morbidity and mortality. Preclinical research has demonstrated the involvement of inflammation in its pathogenesis and in the progression of kidney damage, supporting clinical trials designed to explore anti-inflammatory strategies. However, the recent success of sodium-glucose cotransporter-2 inhibitors and the nonsteroidal mineralocorticoid receptor antagonist finerenone has changed both guidelines and standard of care, rendering obsolete older studies directly targeting inflammatory mediators and the clinical development was discontinued for most anti-inflammatory drugs undergoing clinical trials for DKD in 2016. Given the contribution of inflammation to the pathogenesis of DKD, we review the impact on kidney inflammation of the current standard of care, therapies undergoing clinical trials, or repositioned drugs for DKD. Moreover, we review recent advances in the molecular regulation of inflammation in DKD and discuss potential novel therapeutic strategies with clinical relevance. Finally, we provide a road map for future research aimed at integrating the growing knowledge on inflammation and DKD into clinical practice to foster improvement of patient outcomes.

The markers to delineate different phenotypes of macrophages related to metabolic disorders

Macrophages have a wide variety of roles in physiological and pathological conditions, making them promising diagnostic and therapeutic targets in diseases, especially metabolic disorders, which have attracted considerable attention in recent years. Owing to their heterogeneity and polarization, the phenotypes and functions of macrophages related to metabolic disorders are diverse and complicated. In the past three decades, the rapid progress of macrophage research has benefited from the emergence of specific molecular markers to delineate different phenotypes of macrophages and elucidate their role in metabolic disorders. In this review, we analyze the functions and applications of commonly used and novel markers of macrophages related to metabolic disorders, facilitating the better use of these macrophage markers in metabolic disorder research.

Timing of Mesenchymal Stromal Cell Therapy Defines its Immunosuppressive Effects in a Rat Lung Transplantation Model

Cell therapy using mesenchymal stromal cells (MSCs) is being studied for its immunosuppressive effects. In organ transplantation, the amount of MSCs that accumulate in transplanted organs and other organs may differ depending on administration timing, which may impact their immunosuppressive effects. In vitro, adipose-derived mesenchymal stem cells (ADMSCs) suppress lymphocyte activation under cell-to-cell contact conditions. However, in vivo, it is controversial whether ADMSCs are more effective in accumulating in transplanted organs or in secondary lymphoid organs. Herein, we aimed to investigate whether the timing of ADMSC administration affects its immunosuppression ability in a rat lung transplantation model. In the transplantation study, rats were intramuscularly administered half the usual dose of tacrolimus (0.5 mg/kg) every 24 h after lung transplantation. ADMSCs (1 × 106) were administered via the jugular vein before (PreTx) or after (PostTx) transplantation. Cell tracking using quantum dots was performed. ADMSCs accumulated predominantly in the lung and liver; fewer ADMSCs were distributed in the grafted lung in the PreTx group than in the PostTx group. The rejection rate was remarkably low in the ADMSC-administered groups, particularly in the PostTx group. Serum tumor necrosis factor-α (TNF-α), interferon-γ, and interleukin (IL)-6 levels showed a greater tendency to decrease in the PreTx group than in the PostTx group. The proportion of regulatory T cells in the grafted lung 10 days after transplantation was higher in the PostTx group than in the PreTx group. PostTx administration suppresses rejection better than PreTx administration, possibly due to regulatory T cell induction by ADMSCs accumulated in the transplanted lungs, suggesting a mechanism different from that in heart or kidney transplantation that PreTx administration is more effective than PostTx administration. These results could help establish cell therapy using MSCs in lung transplantation.

Function and mechanism of mesenchymal stem cells in the healing of diabetic foot wounds

Diabetes has become a global public health problem. Diabetic foot is one of the most severe complications of diabetes, which often places a heavy economic burden on patients and seriously affects their quality of life. The current conventional treatment for the diabetic foot can only relieve the symptoms or delay the progression of the disease but cannot repair damaged blood vessels and nerves. An increasing number of studies have shown that mesenchymal stem cells (MSCs) can promote angiogenesis and re-epithelialization, participate in immune regulation, reduce inflammation, and finally repair diabetic foot ulcer (DFU), rendering it an effective means of treating diabetic foot disease. Currently, stem cells used in the treatment of diabetic foot are divided into two categories: autologous and allogeneic. They are mainly derived from the bone marrow, umbilical cord, adipose tissue, and placenta. MSCs from different sources have similar characteristics and subtle differences. Mastering their features to better select and use MSCs is the premise of improving the therapeutic effect of DFU. This article reviews the types and characteristics of MSCs and their molecular mechanisms and functions in treating DFU to provide innovative ideas for using MSCs to treat diabetic foot and promote wound healing.

LPS-pretreatment adipose-derived mesenchymal stromal cells promote wound healing in diabetic rats by improving angiogenesis

Mesenchymal stem cells (MSCs) play a key role in wound healing, and the advantages of pretreated MSCs in wound healing have previously been reported. In the present study, we investigated the impact of LPS pretreated human adipose-derived MSCs on skin wound healing in diabetic rats. We found that some improvements occurred through improving angiogenesis. Then, we scrutinized the impact of lipopolysaccharide (LPS) treatment on human adipose-derived MSCs in a high-glucose (HG) medium, as an in vitro diabetic model. In vivo findings revealed significant improvements in epithelialization and angiogenesis of diabetic wounds which received LPS pre-MSCs. Particularly, LPS pre-MSCs-treated diabetic wounds reached considerably higher percentages of wound closure. Also, the granulation tissue of these wounds had higher pronounced epithelialization and more vascularization compared with PBS-treated and MSCs-treated diabetic ones by CD31, VEGF, CD90, collagen 1, and collagen 3 immunostaining. Western-blots analyses indicated that LPS pre-MSCs led to the upregulation of vascular endothelial growth factor (VEGF) and DNMT1. In addition, significantly higher cell viability (proliferation/colonie), and elevated VEGF and DNMT1 protein expression were observed when MSCs were treated with LPS (10 ng/ml, 6 h) in HG culture media. Based on these findings, it is suggested that LPS pre-MSCs could promote wound repair and skin regeneration, in some major processes, via the improvement of cellular behaviors of MSCs in the diabetic microenvironment. The beneficial advantages of LPS treated with mesenchymal stem cells on wound healing may lead to establishing a novel approach as an alternative therapeutic procedure to cure chronic wounds in diabetic conditions.

S100A8 accelerates wound healing by promoting adipose stem cell proliferation and suppressing inflammation

Adipose-derived stem cells (ADSCs) are stem cells with multidirectional differentiation potential isolated from adipose tissue. They have the same immunomodulatory effect as bone marrow mesenchymal stem cells in wound repair and immune regulation as bone marrow. The mechanism of action of ADSCs in skin wound repair has not been elucidated. S100A8 is a calcium and zinc binding protein, but its role in skin wound healing is rarely reported. We herein show that S100A8 overexpression significantly promoted ADSC proliferation and differentiation, whereas S100A8 knockdown yielded the opposite results. A skin injury model with bone exposure was created in rats by surgically removing the skin from the head and exposing the skull. The wounds were treated with S100A8-overexpressing or S100A8-knockdown ADSCs, and wound healing was monitored. The serum levels of the inflammation-related factors tumor necrosis factor-α and interleukin-6 were decreased significantly after S100A8 overexpression, while the angiogenic factor vascular endothelial growth factor and connective tissue generating factor showed the opposite trend. Histological staining revealed that granulation tissue neovascularization was more pronounced in wounds treated with S100A8-overexpressing ADSCs than that in the control group. We conclude that S100A8 promotes the proliferation of ADSCs and inhibits inflammation to improve skin wound healing.

Current applications of adipose-derived mesenchymal stem cells in bone repair and regeneration: A review of cell experiments, animal models, and clinical trials

In the field of orthopaedics, bone defects caused by severe trauma, infection, tumor resection, and skeletal abnormalities are very common. However, due to the lengthy and painful process of related surgery, people intend to shorten the recovery period and reduce the risk of rejection; as a result, more attention is being paid to bone regeneration with mesenchymal stromal cells, one of which is the adipose-derived mesenchymal stem cells (ASCs) from adipose tissue. After continuous subculture and cryopreservation, ASCs still have the potential for multidirectional differentiation. They can be implanted in the human body to promote bone repair after induction in vitro, solve the problems of scarce sources and large damage, and are expected to be used in the treatment of bone defects and non-union fractures. However, the diversity of its differentiation lineage and the lack of bone formation potential limit its current applications in bone disease. Here, we concluded the current applications of ASCs in bone repair, especially with the combination and use of physical and biological methods. ASCs alone have been proved to contribute to the repair of bone damage in vivo and in vitro. Attaching to bone scaffolds or adding bioactive molecules can enhance the formation of the bone matrix. Moreover, we further evaluated the efficiency of ASC-committed differentiation in the bone in conditions of cell experiments, animal models, and clinical trials. The results show that ASCs in combination with synthetic bone grafts and biomaterials may affect the regeneration, augmentation, and vascularization of bone defects on bone healing. The specific conclusion of different materials applied with ASCs may vary. It has been confirmed to benefit osteogenesis by regulating osteogenic signaling pathways and gene transduction. Exosomes secreted by ASCs also play an important role in osteogenesis. This review will illustrate the understanding of scientists and clinicians of the enormous promise of ASCs’ current applications and future development in bone repair and regeneration, and provide an incentive for superior employment of such strategies.

Diabetic microenvironment preconditioning of adipose tissue-derived mesenchymal stem cells enhances their anti-diabetic, anti-long-term complications, and anti-inflammatory effects in type 2 diabetic rats

Background

Mesenchymal stem cells (MSCs) exert anti-diabetic effects and improve long-term complications via secretory effects that regulate macrophage polarisation and attenuate inflammation. Enhancing the efficacy of MSCs needs to be explored further. The in vitro culture microenvironment influences the secretory profile of MSCs. Therefore, we hypothesised that a diabetic microenvironment would promote the secretion of cytokines responsible for macrophage polarisation, further attenuating systemic inflammation and enhancing the effects of MSCs on type 2 diabetes (T2D) and long-term diabetic complications.

Methods

Preconditioned adipose-derived mesenchymal stem cells (pre-ADSCs) were obtained after co-cultivating ADSCs in a diabetic metabolic environment (including high sugar, advanced glycation end-product, and lipopolysaccharides). The regulatory effects of pre-ADSCs on macrophages were observed in vitro. A T2D rat model was induced with a high-fat diet for 32 weeks combined with an intraperitoneal injection of streptozotocin. Sprague–Dawley (SD) rats were divided into four groups: normal group, diabetes without treatment group (PBS), ADSC treatment group, and pre-ADSC treatment group. ADSCs and pre-ADSCs were intravenously administered weekly to SD rats for 6 months, and then glucose homeostasis and long-term diabetic complications were evaluated in each group.

Results

The secretion of cytokines related to M2 macrophage polarisation (IL-6, MCP-1, etc.) was increased in the pre-ADSC group in the in vitro model. Pre-ADSC treatment significantly maintained blood glucose homeostasis, reduced insulin resistance, promoted islet regeneration, and ameliorated the complications related to diabetes in rats (chronic kidney disease, non-alcoholic steatohepatitis, lung fibrosis, and cataract) compared to the ADSC group (P < 0.05). Additionally, the number of anti-inflammatory M2 macrophage phenotypes was enhanced in tissues following pre-ADSC injections. Moreover, the expression of pro-inflammatory genes (iNOS, TNF-α, IL-1β) was reduced whereas that of anti-inflammatory genes (Arg1, CD206, and Il-10) was increased after cultivation with pre-ADSCs.

Conclusion

Diabetic microenvironment-preconditioned ADSCs effectively strengthen the capacity against inflammation and modulate the progress of long-term T2D complications.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03114-5.

Insufficient S-adenosylhomocysteine hydrolase compromises the beneficial effect of diabetic BMSCs on diabetic cardiomyopathy

Background

Autologous stem cell therapy is a promising strategy for cardiovascular diseases including diabetic cardiomyopathy (DCM), but conclusions from clinical trials were compromised. We assumed that diabetes might induce the dysfunction of stem cells and thus limit its therapeutic effect. This study aimed to compare the effect of diabetes and nondiabetes-derived bone marrow mesenchymal stem cells (BMSCs) transplantation on DCM and explored the potential mechanism.

Methods

Rats with diabetes were induced using high-fat diets and streptozotocin (STZ) injection. BMSCs harvested from diabetic and nondiabetic rats were infused into DCM rats, and the effects on the heart were identified by echocardiography and histopathology. The inhibition or overexpression of SAHH in nondiabetic and diabetic BMSCs was used to confirm its key role in stem cell activity and cardiac therapy.

Results

Compared with normal BMSCs, the therapeutic effects of diabetic rat-derived stem cells on improving cardiac function and adverse remodeling were significantly attenuated. In vitro, diabetic BMSCs had lower cell viability and paracrine function than nondiabetic BMSCs. It was further found that diabetic BMSCs had obvious mitochondrial oxidative stress damage and S-adenosylhomocysteine (SAH) accumulation due to S-adenosylhomocysteine hydrolase (SAHH) deficiency. SAHH inhibition by adenosine dialdehyde (ADA) or shSAHH plasmid in normal BMSCs significantly reduced the favorable effects on endothelial cell proliferation and tube-forming capacity. In contrast, SAHH overexpression in diabetic BMSCs significantly improved cellular activity and paracrine function. Transplantation of BMSCs with SAHH overexpression improved cardiac adverse remodeling and angiogenesis. Activation of the Nrf2 signaling pathway may be one of the key mechanisms of SAHH-mediated improvement of stem cell viability and cardiac repair.

Conclusions

Diabetes leads to compromised bioactivity and repair capacity of BMSCs. Our study suggests that SAHH activation may improve the cardioprotective effect of autologous transplantation of diabetes-derived BMSCs on patients with DCM.

Graphical abstract

Diabetes induced the inhibition of S-adenosylhomocysteine (SAH) expression and aging phenotype in BMSCs and thus decreased the cell viability and paracrine function. Compared with normal BMSCs, the therapeutic effects of diabetic rat-derived BMSCs on improving cardiac function and adverse remodeling were significantly attenuated. SAHH overexpression in diabetic BMSCs significantly rescued cellular function partly via activating Nrf2/HO-1 signal. Transplantation of diabetic BMSCs with SAHH overexpression improved angiogenesis and cardiac adverse remodeling in rats.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03099-1.

Advances in mesenchymal stromal cell therapy for acute lung injury/acute respiratory distress syndrome

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) develops rapidly and has high mortality. ALI/ARDS is mainly manifested as acute or progressive hypoxic respiratory failure. At present, there is no effective clinical intervention for the treatment of ALI/ARDS. Mesenchymal stromal cells (MSCs) show promise for ALI/ARDS treatment due to their biological characteristics, easy cultivation, low immunogenicity, and abundant sources. The therapeutic mechanisms of MSCs in diseases are related to their homing capability, multidirectional differentiation, anti-inflammatory effect, paracrine signaling, macrophage polarization, the polarization of the MSCs themselves, and MSCs-derived exosomes. In this review, we discuss the pathogenesis of ALI/ARDS along with the biological characteristics and mechanisms of MSCs in the treatment of ALI/ARDS.

Expression of TNF-α and IL-1β in Peripheral Blood of Patients with T2DM Retinopathy

Aims

The expression and clinical significance of tumor necrosis factor-α (INF-α) and interleukin 1-β (IL-1β) in retinal cells of patients with type 2 diabetes (T2DM) retinopathy were detected by flow cytometry.

Materials and Methods

Fifty patients with T2DM who attended our ophthalmology clinic between May 2021 and May 2022 were selected as the observation group. Another 50 healthy individuals who were examined at our hospital during the same period were selected as the comparison group. Tear film rupture time (BUT), fluorescein staining (FL), basal tear secretion (Schirmer I) test, and conjunctival impression cytology (CIC) were detected in both groups, and the expression of TNF-α and IL-1β in retinal cells was observed by immunohistochemical staining.

Results

The levels of IL13 and TNF-α in the two groups were not exactly the same. The serum levels of IL13 and TNF-α in the observation group were significantly higher than those in the control group, and there was a statistically significant difference (P < 0.05). TNF-α and IL-1B expressions in the observation group were positively correlated with the fluorescence staining, and the expression of TNF-α and IL-1β in the observation group was significantly negatively correlated with the BUT test and Schirmer I test.

Conclusion

Serums TNF-α and IL-1β are significantly elevated in patients with T2DM retinopathy and gradually increase with disease progression. Combined detection of serums TNF-α and IL-1β can help determine the severity of the disease and assess the prognosis.

Using adipose-derived mesenchymal stem cells to fight the metabolic complications of obesity: Where do we stand?

Obesity is a critical risk factor for the development of metabolic diseases, and its prevalence is increasing worldwide. Stem cell-based therapies have become a promising tool for therapeutic intervention. Among them are adipose-derived mesenchymal stem cells (ADMSCs), secreting numerous bioactive molecules, like growth factors, cytokines, and chemokines. Their unique features, including immunosuppressive and immunomodulatory properties, make them an ideal candidates for clinical applications. Numerous experimental studies have shown that ADMSCs can improve pancreatic islet cell viability and function, ameliorate hyperglycemia, improve insulin sensitivity, restore liver function, counteract dyslipidemia, lower pro-inflammatory cytokines, and reduce oxidative stress in the animal models. These results prompted scientists to use ADMSCs clinically. However, up to date, there have been few clinical studies or ongoing trails using ADMSCs to treat metabolic disorders such as type 2 diabetes mellitus (T2DM) or liver cirrhosis. Most human studies have implemented autologous ADMSCs with minimal risk of cellular rejection. Because the functionality of ADMSCs is significantly reduced in subjects with obesity and/or metabolic syndrome, their efficacy is questioned. ADMSCs transplantation may offer a potential therapeutic approach for the treatment of metabolic complications of obesity, but randomized controlled trials are required to establish their safety and efficacy in humans prior to routine clinical use.

Human adipose-derived stem cell-loaded small intestinal submucosa as a bioactive wound dressing for the treatment of diabetic wounds in rats

Chronic nonhealing wounds are one of the most common and serious complications of diabetes, which can lead to disability of patients. Adipose-derived stem cells (ADSCs) have emerged as a promising tool for skin wound healing, but the therapeutic potential depends considerably on the cell delivery system. Small intestinal submucosa (SIS) is an extracellular matrix-based membranous scaffold with outstanding repair potential for skin wounds. In this study, we first fabricated a bioactive wound dressing, termed the SIS+ADSCs composite, by using human ADSCs as the seed cell and porcine SIS as the cell delivery vehicle. Then, we systematically investigated, for the first time, the healing potential of this wound dressing in a rat model of type 2 diabetes. In vitro studies revealed that SIS provided a favorable microenvironment for ADSCs and significantly promoted the expression of growth factors critical for chronic wound healing. After implantation in the full-thickness skin wounds of diabetic rats, the SIS+ADSCs composite showed a higher wound healing rate and wound healing quality than those in the PBS, ADSCs, and SIS groups. Along with the ability to modulate the polarization of macrophages in vivo, the SIS+ADSCs composite was potent at promoting wound angiogenesis, reepithelialization, and skin appendage regeneration. Taken together, these results indicate that the SIS+ADSCs composite has good therapeutic potential and high translational value for diabetic wound treatment.

NEAT1: A novel long non-coding RNA involved in mediating type 2 diabetes and its various complications

Background:

Nuclear‐enriched abundant transcript 1 (abbreviated as NEAT1) refers to a long-chain non-coding RNA involved within various physiological and pathological processes. This study aimed at clarifying the effect and molecule system of neat1 within nonalcoholic fatty liver disease (NAFLD) as well as type 2 diabetes (T2DM).

Method:

In this review, we summarize and analyze current studies concerning mechanisms of NEAT1 in the development of type 2 diabetes and its complications. Also, we search the papers of NEAT1 in applying to NAFLD. The related studies were obtained through a systematic search of Pubmed.

Results:

Neat1 displays a close correlation with how T2DM occurs and develops, and it was confirmed to be significantly up-regulated in T2DM and its various complications (e.g., diabetics nephropathy, diabetics cardiomyopathy, diabetics retinopathy as well as diabetic neuropathy). Besides, neat1 is capable of impacting the occurrence, development and prognosis of NAFLD and T2DM.

Conclusion:

LncRNA neat1 is likely to act as a novel therapeutic target for and T2DM and its complications. Moreover, nonalcoholic fatty liver disease is also correlated with NEAT1.

Administration of mesenchymal stem cells in diabetic kidney disease: mechanisms, signaling pathways, and preclinical evidence

Diabetic kidney disease (DKD) is a serious microvascular complication of diabetes. Currently, the prevalence and mortality of DKD are increasing annually. However, with no effective drugs to prevent its occurrence and development, the primary therapeutic option is to control blood sugar and blood pressure. Therefore, new and effective drugs/methods are imperative to prevent the development of DKD in patients with diabetes. Mesenchymal stem cells (MSCs) with multi-differentiation potential and paracrine function have received extensive attention as a new treatment option for DKD. However, their role and mechanism in the treatment of DKD remain unclear, and clinical applications are still being explored. Given this, we here provide an unbiased review of recent advances in MSCs for the treatment of DKD in the last decade from the perspectives of the pathogenesis of DKD, biological characteristics of MSCs, and different molecular and signaling pathways. Furthermore, we summarize information on combination therapy strategies using MSCs. Finally, we discuss the challenges and prospects for clinical application.

Stromal Vascular Fraction and Mesenchymal Stem Cells from Human Adipose Tissue: A Comparison of Immune Modulation and Angiogenic Potential

INTRODUCTION

In recent years, both stromal vascular fraction (SVF) from adipose tissue and mesenchymal stem cells (MSC) from adipose tissues were extensively used in both preclinical and clinical treatment for various diseases. Some studies reported differences in treatment efficacy between SVFs and MSCs in animals as well as in humans. Therefore, this study is aimed to evaluate the immune modulation and angiogenic potential of SVFs and MSCs from the same SVF samples to support an explanation when SVFs or MSCs should be used.

METHODS

The adipose tissue samples from ten female donors with consent forms were collected. SVFs from these samples were isolated according to the published protocols. The existence of mesenchymal cells that positive with CD44, CD73, CD90, and CD105 and endothelial progenitor cells that positive with CD31 and CD34 was determined using flow cytometry. Three samples of SVFs with similar percentages of mesenchymal cell portion and endothelial progenitor cell portion were used to isolate MSCs. Obtained MSCs were confirmed as MSCs using the ISCT minimal criteria. To compare the immune modulation of SVF and MSCs, the mixed lymphocyte assay was used. The lymphocyte proliferation, as well as IFN-gamma and TNF-alpha concentrations, were determined. To compare the angiogenic potential, the angiogenesis in quail embryo assay was used. The angiogenesis efficacy was measured based on the vessel areas formed in the embryos after 7 days.

RESULTS

The results showed that all SVF samples contained the portions of mesenchymal cells and endothelial progenitor cells. MSCs from SVFs meet all minimal criteria of MSCs that suggested by ISCT. MSCs from SVFs efficiently suppressed the immune cell proliferation compared to the SVFs, especially at ratios of 1:4 (1 MSCs: 4 immune cells). MSCs also inhibited the IFN-gamma and TNF-alpha production more efficiently than SVFs (p < 0.05). However, in quail embryo models, SVFs triggered the angiogenesis and neovessel formation better than MSCs with more significant vessel areas after 7 days (p < 0.05).

CONCLUSION

This study suggested that SVFs and MSCs have different potentials for immune modulation and angiogenesis. SVFs help the angiogenesis better than MSCs, while MSCs displayed the more significant immune modulation. These results can guide the usage of SVFs or MSCs in disease treatment.

Human umbilical cord-derived mesenchymal stem cells alleviate insulin resistance in diet-induced obese mice via an interaction with splenocytes

Background

Previous research has demonstrated that the spleen plays an important role in mesenchymal stem cell (MSC)-mediated alleviation of acute inflammation, as MSC infusion increases the spleen-derived anti-inflammatory cytokine interleukin 10 (IL-10) levels. However, studies on splenic involvement in MSC-induced protection against chronic inflammatory diseases are limited. Obesity is characterized by chronic low-grade inflammation, a key driver of insulin resistance. This study aims to evaluate the effects of MSCs on obesity-related insulin resistance and explore the underlying mechanism, particularly regarding splenic involvement.

Methods

We induced obesity in mice by feeding them high-fat diets for 20 weeks. Human umbilical cord-derived MSCs (UC-MSCs) were systemically infused into the obese mice once per week for 6 weeks. Systemic glucose metabolic homeostasis and insulin sensitivity in epididymal adipose tissue (EAT) were evaluated. Then, we conducted in vivo blockade of IL-10 during UC-MSC infusion by intraperitoneally administrating an IL-10-neutralizing antibody twice per week. We also investigated the therapeutic effects of UC-MSCs on obese mice after removal of the spleen by splenectomy.

Results

UC-MSC infusions improved systemic metabolic homeostasis and alleviated insulin resistance in EAT but elicited no change in weight. Despite rare engraftment of UC-MSCs in EAT, UC-MSC infusions attenuated insulin resistance in EAT by polarizing macrophages into the M2 phenotype, coupled with elevated serum IL-10 levels. In vivo blockade of IL-10 blunted the effects of UC-MSCs on obese mice. Furthermore, UC-MSCs overwhelmingly homed to the spleen, and the ability of UC-MSCs to elevate serum IL-10 levels and alleviate insulin resistance was impaired in the absence of the spleen. Further in vivo and in vitro studies revealed that UC-MSCs promoted the capacity of regulatory T cells (Treg cells) to produce IL-10 in the spleen.

Conclusions

Our results demonstrated that UC-MSCs elevated serum IL-10 levels and subsequently promoted macrophage polarization, leading to alleviation of insulin resistance in EAT. The underlying mechanism was that UC-MSCs improved the capacity of Treg cells to produce IL-10 in the spleen. Our findings indicated that the spleen played a critical role in amplifying MSC-mediated immunomodulatory effects, which may contribute to maximizing MSC efficacy in clinical applications in the future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02791-6.

Anti-inflammatory effects of mesenchymal stem cell-conditioned media inhibited macrophages activation in vitro

The immunomodulatory effects of mesenchymal stem cells (MSCs) on macrophages have been reported, however, the underlying mechanism remains unknown. Therefore, this study aimed to investigate the anti-inflammatory effects of MSCs on lipopolysaccharide (LPS)-stimulated macrophages and the subsequent downregulation of their inflammatory mediators. Macrophages were treated with conditioned media from MSCs, without a subsequent change of MSCs responding to the inflammation state. This study also evaluated whether the interleukin (IL) 4 stimulation of MSCs can improve their anti-inflammatory effects. Results demonstrated that the MSC-conditioned medium (MSC-CM) stimulated with IL4 significantly inhibited inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression of LPS-activated macrophages. MSC-CM treatment inhibited the mRNA transcription of the cytokines IL1β and IL6, the chemokines C–C motif ligand (CCL) 2, CCL3, CCL4, and CCL5, and the chemokine receptors CCR2 and CCR5, in LPS-stimulated macrophages. As revealed through western blot and immunofluorescence analyses, the phosphorylation of p38, JNK, and ERK MAPKs, as well as phosphorylation of NF-κB in stimulated macrophages, were also inhibited by the MSC-CM. Further, more potent anti-inflammatory effects were observed with the IL4-stimulated cells, compared with those observed with the non-stimulated cells. The MSC-CM demonstrated a potent anti-inflammatory effect on LPS-activated macrophages, while the IL4 stimulation improved this effect. These findings indicate that MSCs could exert anti-inflammatory effects on macrophages, and may be considered as a therapeutic agent in inflammation treatment.