Comparative analysis of effects of conditioned mediums obtained from 2D or 3D cultured mesenchymal stem cells on kidney functions of diabetic rats: Early intervention could potentiate transdifferentiation of parietal epithelial cell into podocyte precursors.

AIM: The secretome of mesenchymal stem cells (MSCs) could be a potential therapeutic intervention for diabetes and associated complications like nephropathy. This study aims to evaluate the effects of conditioned mediums (CMs) collected from umbilical cord-derived MSCs incubated under 2-dimensional (2D) or 3D culture conditions on kidney functions of rats with type-I diabetes (T1D). MAIN METHODS: Sprague-Dawley rats were treated with 20 mg/kg streptozocin for 5 consecutive days to induce T1D, and 12 doses of CMs were applied intraperitoneally for 4 weeks. The therapeutic effects of CMs were comparatively investigated by biochemical, physical, histopathological, and immunohistochemical analysis. KEY FINDINGS: 3D-CM had significantly higher total protein concentration than the 2D-CM Albumin/creatinine ratios of both treatment groups were significantly improved in comparison to diabetes. Light microscopic evaluations showed that glomerular and cortical tubular damages were significantly ameliorated in only the 3D-CM applied group compared to the diabetes group, which were correlated with transmission electron microscopic observations. The nephrin and synaptopodin expressions increased in both treatment groups compared to diabetes. The WT1, Ki-67, and active caspase-3 expressions in glomeruli and parietal layers of the treatment groups suggest that both types of CMs suppress apoptosis and promote possible parietal epithelial cells' (PECs') transdifferentiation towards podocyte precursor cells by switching on WT1 expression in parietal layer rather than inducing new cell proliferation. SIGNIFICANCE: 3D-CM was found to be more effective in improving kidney functions than 2D-CM by ameliorating glomerular damage through the possible mechanism of transdifferentiation of PECs into podocyte precursors and suppressing glomerular apoptosis.

Preconditioning of human umbilical cord mesenchymal stem cells with deferoxamine potentiates the capacity of the secretome released from the cells and promotes immunomodulation and beta cell regeneration in a rat model of type 1 diabetes.

This study aimed to examine the effects of the secretome released by human umbilical cord-mesenchymal stem cells (MSC) as a result of preconditioning with deferoxamine (DFX), a hypoxia mimetic agent, on type 1 diabetes (T1D), by comparing it with the secretome produced by untreated MSCs. Initially, the levels of total protein, IL4, IL10, IL17, and IFNγ in the conditioned medium (CM) obtained from MSCs subjected to preconditioning with 150 µM DFX (DFX-CM) were analyzed in comparison to CM derived from untreated MSCs (N-CM). Subsequently, the CMs were administered to rats with T1D within a specific treatment plan. Following the sacrification, immunomodulation was evaluated by measuring serum cytokine levels and assessing the regulatory T cell (Treg) ratio in spleen mononuclear cells. Additionally, ß-cell mass was determined in the islets by immunohistochemical labeling of NK6 Homeobox 1 (Nkx6.1), Pancreatic duodenal homeobox-1 (Pdx1), and insulin antibodies in pancreatic sections. In vitro findings indicated that the secretome levels of MSCs were enhanced by preconditioning with DFX. In vivo, the use of DFX-CM significantly increased the Treg population, and accordingly, the level of inflammatory cytokines decreased. In ß-cell marker labeling, D + DFX-CM showed significantly increased PDX1 and insulin immunoreactivity. In conclusion, while the factors released by MSCs without external stimulation had limited therapeutic effects, substantial improvements in immunomodulation and ß-cell regeneration were seen with DFX-preconditioned cell-derived CM.

Investigation of conditioned medium properties obtained from human umbilical cord mesenchymal stem/stromal cells preconditioned with dimethyloxalylglycine in a correlation with ultrastructural changes.

Mesenchymal stem/stromal cells (MSCs) hold significant therapeutic value due to their regeneration abilities, migration capacity, and immunosuppressive and immunomodulatory properties. These cells secrete soluble and insoluble factors, and this complex secretome contributes to their therapeutic effect. Furthermore, stimulation of cells by various external stimuli lead to secretome modifications that can increase the therapeutic efficacy. So, this study examined the effect of dimethyloxalylglycine (DMOG), a hypoxia-mimetic agent, on secretome profiles and exosome secretions of MSCs by evaluating conditioned medium (CM) and ultrastructural morphologies of the cells in comparison with unpreconditioned MSCs. The appropriate dose and duration of the use of DMOG were determined as 1000 µM and 24 h by evaluating the HIF-1α expression. DMOG-CM and N-CM were collected from MSCs incubated in serum-free medium with/without DMOG for 24 h, respectively. The content analysis of conditioned mediums (CMs) revealed that VEGF, NGF, and IL-4 levels were increased in DMOG-CM. Subsequently, exosomes were isolated from the CMs and were shown by transmission electron microscopy and Western blot analysis in both groups. The effects of CMs on proliferation and migration were determined by in vitro wound healing tests; both CMs increased the fibroblast's migratory and proliferative capacities. According to the ultrastructural evaluation, autophagosome, autolysosome, myelin figure, and microvesicular body structures were abundant in DMOG-preconditioned MSCs. Consistent with the high number of autophagic vacuoles, Beclin-1 expression was increased in those cells. These findings suggested that DMOG could alter MSCs' secretion profile, modify their ultrastructural morphology accordingly, and make the CM a more potent therapeutic tool. RESEARCH HIGHLIGHTS: Preconditioning mesenchymal stem/stromal cells with dimethyloxalylglycine, a hypoxia-mimetic agent, could modify cellular metabolism. Hypoxic mechanisms lead to alterations in the ultrastructural characteristics of mesenchymal stromal/stem cells. Preconditioning with dimethyloxalylglycine leads to ultrastructural and metabolic changes of mesenchymal stromal/stem cells along with modifications in their secretome profiles. Preconditioning of mesenchymal stromal/stem cells could render them a more potent therapeutic tool.

2D and 3D cultured human umbilical cord-derived mesenchymal stem cell-conditioned medium has a dual effect in type 1 diabetes model in rats: immunomodulation and beta-cell regeneration.

BACKGROUND: Type 1 diabetes (T1D) is a T-cell-mediated autoimmune disease characterized by the irreversible destruction of insulin-producing ß-cells in pancreatic islets. Helper and cytotoxic T-cells and cytokine production, which is impaired by this process, take a synergetic role in ß-cell destruction, and hyperglycemia develops due to insulin deficiency in the body. Mesenchymal stem cells (MSCs) appear like an excellent therapeutic tool for autoimmune diseases with pluripotent, regenerative, and immunosuppressive properties. Paracrine factors released from MSCs play a role in immunomodulation by increasing angiogenesis and proliferation and suppressing apoptosis. In this context, the study aims to investigate the therapeutic effects of MSC's secretomes by conditioned medium (CM) obtained from human umbilical cord-derived MSCs cultured in 2-dimensional (2D) and 3-dimensional (3D) environments in the T1D model. METHODS: First, MSCs were isolated from the human umbilical cord, and the cells were characterized. Then, two different CMs were prepared by culturing MSCs in 2D and 3D environments. The CM contents were analyzed in terms of total protein, IL-4, IL-10, IL-17, and IFN-λ. In vivo studies were performed in Sprague-Dawley-type rats with an autoimmune T1D model, and twelve doses of CM were administered intraperitoneally for 4 weeks within the framework of a particular treatment model. In order to evaluate immunomodulation, the Treg population was determined in lymphocytes isolated from the spleen after sacrification, and IL-4, IL-10, IL-17, and IFN-λ cytokines were analyzed in serum. Finally, ß-cell regeneration was evaluated immunohistochemically by labeling Pdx1, Nkx6.1, and insulin markers, which are critical for the formation of ß-cells. RESULTS: Total protein and IL-4 levels were higher in 3D-CM compared to 2D-CM. In vivo results showed that CMs induce the Treg population and regulate cytokine release. When the immunohistochemical results were evaluated together, it was determined that CM application significantly increased the rate of ß-cells in the islets. This increase was at the highest level in the 3D-CM applied group. CONCLUSION: The dual therapeutic effect of MSC-CM on immunomodulation and homeostasis/regeneration of ß-cells in the T1D model has been demonstrated. Furthermore, this effect could be improved by using 3D scaffolds for culturing MSCs while preparing CM.

Therapeutic potential of conditioned medium obtained from deferoxamine preconditioned umbilical cord mesenchymal stem cells on diabetic nephropathy model.

BACKGROUND: The therapeutic potential of mesenchymal stem cells (MSCs)-derived conditioned media (CM) can be increased after preconditioning with various chemical agents. The aim of this study is comparative evaluation of effects of N-CM and DFS-CM which are collected from normal (N) and deferoxamine (DFS) preconditioned umbilical cord-derived MSCs on rat diabetic nephropathy (DN) model. METHODS: After incubation of the MSCs in serum-free medium with/without 150 µM DFS for 48 h, the contents of N-CM and DFS-CM were analyzed by enzyme-linked immunosorbent assay. Diabetes (D) was induced by single dose of 55 mg/kg streptozotocin. Therapeutic effects of CMs were evaluated by biochemical, physical, histopathological and immunohistochemical analysis. RESULTS: The concentrations of vascular endothelial growth factor alpha, nerve growth factor and glial-derived neurotrophic factor in DFS-CM increased, while one of brain-derived neurotrophic factor decreased in comparison with N-CM. The creatinine clearance rate increased significantly in both treatment groups, while the improvement in albumin/creatinine ratio and renal mass index values were only significant for D + DFS-CM group. Light and electron microscopic deteriorations and loss of podocytes-specific nephrin and Wilms tumor-1 (WT-1) expressions were significantly restored in both treatment groups. Tubular beclin-1 expression was significantly increased for DN group, but it decreased in both treatment groups. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive apoptotic cell death increased in the tubules of D group, while it was only significantly decreased for D + DFS-CM group. CONCLUSIONS: DFS-CM can be more effective in the treatment of DN by reducing podocyte damage and tubular apoptotic cell death and regulating autophagic activity with its more concentrated secretome content than N-CM.

Effects of SGLT2 inhibitors on patients with diabetic kidney disease: A preliminary study on the basis of podocyturia.

BACKGROUND: The aim of this study was to investigate the effects of sodium glucose cotransporter 2 inhibitors (SGLT2i) on the glomerulus through the evaluation of podocyturia in patients with diabetic kidney disease (DKD). METHODS: The study population was composed of 40 male patients with type 2 diabetes mellitus; 22 of them received SGLT2i (SGLT2i group), and the others who did not were the control. The DKD-related parameters of patients were monitored before SGLT2i initiation, and then in the third and sixth month of the follow-up period. Patients' demographic, clinical, laboratory, and follow-up data were obtained from medical charts. Microalbuminuria was measured in 24-h urine. The number of podocytes in the urine was determined by immunocytochemical staining of two different markers, namely podocalyxin (podx) and synaptopodin (synpo). Concentrations of urine stromal cell-derived factor 1a and vascular endothelial growth factor cytokines were quantified with an enzyme-linked immunosorbent assay kit. RESULTS: At the end of the follow-up period, decreases in glycosylated hemoglobin, glucose, systolic and diastolic blood pressure, uric acid level, and microalbuminuria, and improvement in body mass index level and weight loss were significant for the SGLT2i group. On the other hand, there was no significant difference in terms of these parameters in the control group. The excretion of synaptopodin-positive (synpo+ ) and podocalyxin-positive (podx+ ) cells was significantly reduced at the end of the follow-up period for the SGLT2i group, while there was no significant change for the control. CONCLUSIONS: At the end of the follow-up period, male patients receiving SGLT2i had better DKD-related parameters and podocyturia levels compared to baseline and the control group. Our data support the notion that SGLT2i might have structural benefits for glomerular health.

The Keystone, Scroll Complex, and Interdomal Area of the Nose: Histologic and Anatomical Observations.

Comprehensive knowledge of nasal anatomy is essential for obtaining aesthetically and functionally pleasing results in rhinoplasty. In this study, the authors described the anatomy, histology, and clinical relevance of the interdomal region, keystone, and scroll complex. The current study examined these areas in 26 fresh cadaver heads. All cadavers were fresh, and no conservation or freezing processes were applied. All dissections were performed by the first author. It was determined that the structure that connected the middle crura in the interdomal region actually came together in the transverse plane and contained abundant capillaries within. It was observed that chondroblasts with high regenerative potential were present in the keystone area, and there was very tight attachment between periosteum and perichondrium. The scroll complex was found to be more flexible and thin and had fewer regenerative cells compared to the keystone region. With its unique anatomy and histology, the keystone acts as a transition area between the flexible and fixed units of the nose. The scroll complex should be taken into consideration during rhinoplasty because of its effects on fixation of the skin in the lateral supratip area and functional effects on internal and external nasal valves. The interdomal ligament, in contrast, acts as a transition between both middle crura rather than a real ligament.

In-vitro investigation of calcitonin associated effects on the trophoblastic cells.

Calcitonin is expressed in the epithelium of endometrium, and modulates zonula adherens junctions which are composed of cadherin-catenins complex during the implantation window. Trophoblastic cells which have complex interaction with the epithelial cells of endometrium during implantation were demonstrated to have calcitonin receptors. Mechanism of action of calcitonin on trophoblastic cells has not yet been elucidated. Therefore, it was aimed to determine the effects of calcitonin on the expressions of ß-catenin and phospho-ß-catenin in a dose depended manner under the influence of progesterone and estrogen hormones (P + E) by using JAR cell line through the immunocytochemical and Western blot analyses. Moreover, adherens junctions (AJs) were ultrastructurally investigated to assess the involvement of cadherin-catenin complex in accordance with the changes in the specified parameters. Immunocytochemical analysis showed that only 10 nM calcitonin treated group had increased expression of membranous ß-catenin compared to the control group, while there was decreased expression of ß-catenin in the nucleus of all the experimental groups. Cytoplasmic expressions of the phospho-ß-catenin decreased in all experimental groups compared to the control group while the decrease in the nuclear expression was remarkable in the groups treated with P + E, and P + E + 250 nM calcitonin. Western blot analysis showed that total ß-catenin and phospho-ß-catenin expressions were not significantly different. Ultrastructural analysis showed that increase in the number of AJs was noticeable in the group treated with 10 nM calcitonin. Overall, the localization and expression levels of ß-catenin and phospho-ß-catenin suggest that calcitonin could show its effects through the non-canonical pathway in the trophoblastic cells.

Comparison of different cryopreservation protocols for human umbilical cord tissue as source of mesenchymal stem cells.

The main purpose of this study is to establish an effective cryopreservation protocol for the umbilical cord tissue as a source of mesenchymal stem cells (MSCs). In this context, it was aimed to use a cryoprotectant that could be an alternative to dimethyl sulfoxide (DMSO) which is commonly used despite the toxic side effects. Therefore, two different cryopreservation solutions were prepared using 10% DMSO and 10% 1,2 propanediol (PrOH). The fresh tissue group that was not performed cryopreservation was used as the control group. Following the cryopreservation step, MSCs were isolated from all groups and compared with each other to assess the efficiency of the cryopreservation solutions. The comparison was performed in terms of followings: morphology, immunophenotypes, growth kinetics, differentiation, and ultrastructural features. Based on the results, there were no significant morphological and immunophenotypic differences between the MSCs isolated from cryopreserved tissue groups and the MSCs isolated from the fresh tissue group. According to the growth kinetic analysis, the cells isolated from the PrOH group had a lower proliferation rate than the cells isolated from the fresh tissue. However, there was no significant difference between the cryopreserved groups in this respect. Osteogenic and adipogenic differentiation was observed in all groups. Upon comparison of the cryopreserved groups, PrOH group was discovered to hold a minor superiority in terms of these modes of differentiation. These results suggest that PrOH, which is considered as a cryoprotectant with low toxicity, could be used as a preferred cryoprotectant instead of DMSO concerning the process of cryopreservation of the umbilical cord.

Ultrastructural analysis of human umbilical cord derived MSCs at undifferentiated stage and during osteogenic and adipogenic differentiation.

Mesenchymal stem cells (MSCs) are considered as an important tool for regenerative medicine and experimental treatments. Unveiling the ultrastructural changes during the differentiation of MSCs might help us to understand the nature of the process and to develop novel therapeutic approaches. For this purpose, human umbilical cord (hUC) was chosen as MSC source. In the first place, MSCs were isolated from sub-amniotic, intervascular and perivascular areas of hUC by enzymatic and tissue explant method to determine the most favorable region of hUC and technique for further processing. Therefore, microscopic and growth kinetics analyses showed that there was no clear difference in the morphologies and proliferation rates among the hUC-MSC groups. Flow cytometric analysis showed that CD44 and CD90 MSC markers were highly expressed, while CD34 and CD45 hematopoietic stem cells markers were expressed at low degree. Because our preliminary results showed that there was no conspicuous superiority among the hUC-MSCs groups, whole UC was utilized as a source, and tissue explant method was applied to isolate MSCs for further differentiation analysis. At the 1st and 3rd week of osteogenic and adipogenic differentiation, ultrastructural analysis showed an increase in the number of secondary lysosomes in comparison with the undifferentiated status. Increase in the mitochondrial content was also detected at the 1st week of adipogenic differentiation. Consequently, ultrastructural changes including increase in the number of mitochondria and secondary lysosomes during the adipogenic and osteogenic differentiation could be attributed to the switch in energy metabolism of the MSCs and increment in the lysosomal activity respectively.

Effects of resveratrol on high-fructose-induced testis injury in rats.

This study investigated whether a high-fructose (HFr) diet changes the morphology of seminiferous tubules (ST) in rats and resveratrol (RES) has a possible restoring effect in this sense. Fructose (30%; w/v) was administered to rats alone or together with RES (50 mg/L) in drinking water for 8 weeks. In the HFr group, destruction of the germinal epithelium led to the detection of immature germ cells in the lumen. HFr diet gave rise to a decrease in the ST diameters (p < 0.05), Johnsen's tubular biopsy score values (p < 0.001), and an increase in the apoptotic index (p < 0.05). Ultrastructurally, HFr feeding increased lipid accumulation (p < 0.01), mitochondrial damage, and acrosomal abnormalities in spermatogenic cells. Treatment of HFr -fed rats with RES improved the reduced ST diameters and overall general histological and ultrastructural abnormalities of the STs, but did not change the increased apoptotic index.