Cells In Diabetic Patients Research Articles

Cellular Senescence: A Bridge Between Diabetes and Microangiopathy

Cellular senescence is a state of permanent cell cycle arrest and plays an important role in many vascular lesions. This study found that the cells of diabetic patients have more characteristics of senescence, which may cause microvascular complications. Cell senescence, as one of the common fates of cells, links microangiopathy and diabetes. Cell senescence in a high-glucose environment can partially elucidate the mechanism of diabetic microangiopathy, and various types of cellular senescence induced by it can promote the progression of diabetic microangiopathy. Still, the molecular mechanism of microangiopathy-related cellular senescence has not yet been clearly studied. Building on recent research evidence, we herein summarize the fundamental mechanisms underlying the development of cellular senescence in various microangiopathies associated with diabetes. We gradually explain how cellular senescence serves as a key driver of diabetic microangiopathy. At the same time, the treatment of basic senescence mechanisms such as cellular senescence may have a great impact on the pathogenesis of the disease, may be more effective in preventing the development of diabetic microangiopathy, and may provide new ideas for the clinical treatment and prognosis of diabetic microangiopathy.

#1324 The antiproteinuric effect of Gliflozins is associated with the mitochondrial density of endothelial cells in diabetic patients

Abstract Background and Aims The sodium-glucose co-transporter type 2 inhibitors (SGLT2i) such as dapagliflozin and empagliflozin, are a new class of nephro- and cardio-protective drugs in diabetic and non-diabetic patients. SGLT2 is greatly expressed in the proximal tubule cells, and therefore the protective effects of gliflozins are thought to be mediated by a hemodynamic mechanism on glomerular hyperfiltration. However, they could be acting also in other cell types, particularly in diabetic patients, because hyperglycemia induces the expression of SGLT2 in endothelial cells, mesangial cells, cardiomyocytes, etc. Because SGLT2 changes the intracellular concentration of sodium and glucose, gliflozins may indirectly change mitochondrial swelling and activity. In this study, we have tested the hypothesis that gliflozins act on mitochondria in patients suffering from diabetes. Method We have analyzed kidney biopsies from diabetic patients in treatment with a gliflozin (n = 10) or without gliflozin treatment (n = 10) stained with fuchsin red, which gives a color intensity proportional to mitochondrial content. Clinical variables (albumin-creatinine ratio (ACR), blood pressure, eGFR, glycated albumin) have been measured before and after 4 months of treatment. Images have been acquired using a Zeiss Axioscope with 100x objective and analyzed using ImageJ software to quantify staining intensity (expressed as optical density) after background subtraction. Two different cell types have been considered: proximal tubule cells and endothelial cells in glomeruli. Only non-sclerotic glomeruli have been considered. Results The systolic blood pressure was linearly correlated to the intensity of staining of mitochondria in the proximal tubule cells in all patients irrespective of gliflozin treatment. In non-treated diabetic patients, the mitochondrial content of endothelial cells was not related to the extent of ACR reduction over time. In diabetic patients treated with gliflozins, the extent of ACR reduction after treatment was correlated with the intensity of mitochondrial staining in glomerular endothelial cells. This correlation was not present in proximal tubule cells. Gliflozin treatment may induce a change in the mitochondrial content of endothelial cells, particularly in patients responding with a reduction in proteinuria. Conclusion Proteinuria in diabetic patients depends on damage in both the endothelial and podocyte compartments. Gliflozins may improve proteinuria by a hemodynamic mechanism; however, our data suggest an effect of gliflozins specific on mitochondria of the endothelial cells in the glomeruli, which is proportional to their anti-proteinuric effect. Though we do not analyze the mechanism of gliflozins on mitochondria, it is possible to speculate that the changes of intracellular sodium-induced by gliflozins may induce an altered mitochondrial activity.

A hybrid construct of decellularized matrix and fibrin for differentiating adipose stem cells into insulin-producing cells, an optimized in vitro assessment.

The generation of insulin-producing cells (IPCs) is an attractive approach for replacing damaged β cells in diabetic patients. In the present work, we introduced a hybrid platform of decellularized amniotic membrane (dAM) and fibrin encapsulation for differentiating adipose tissue-derived stem cells (ASCs) into IPCs. ASCs were isolated from healthy donors and characterized. Human AM was decellularized, and its morphology, DNA, collagen, glycosaminoglycan (GAG) contents, and biocompatibility were evaluated. ASCs were subjected to four IPC differentiation methods, and the most efficient method was selected for the experiment. ASCs were seeded onto dAM, alone or encapsulated in fibrin gel with various thrombin concentrations, and differentiated into IPCs according to a method applying serum-free media containing 2-mercaptoethanol, nicotinamide, and exendin-4. PDX-1, GLUT-2 and insulin expression were evaluated in differentiated cells using real-time PCR. Structural integrity and collagen and GAG contents of AM were preserved after decellularization, while DNA content was minimized. Cultivating ASCs on dAM augmented their attachment, proliferation, and viability and enhanced the expression of PDX-1, GLUT-2, and insulin in differentiated cells. Encapsulating ASCs in fibrin gel containing 2 mg/ml fibrinogen and 10 units/ml thrombin increased their differentiation into IPCs. dAM and fibrin gel synergistically enhanced the differentiation of ASCs into IPCs, which could be considered an appropriate strategy for replacing damaged β cells.

Histone Deacetylase Inhibitors Restore the Odontogenic Differentiation Potential of Dental Pulp Stem Cells under Hyperglycemic Conditions.

Complications arising from diabetes can result in stem cell dysfunction, impairing their ability to undergo differentiation into various cellular lineages. The present study evaluated the effect of histone deacetylase inhibitors, Valproic acid and Trichostatin A, on the odontogenic differentiation potential of dental pulp stem cells under hyperglycemic conditions. Streptozotocin (STZ) induced diabetes mellitus in 12 male Wistar rats. Dental parameters were examined using micro-computed tomography. The odontogenic potential of human pulp stem cells exposed to 30 mM glucose was assessed through alkaline phosphatase assays, examination of gene expression for dentin matrix protein 1 and dentin sialoprotein using real-time PCR, and alizarin red staining for calcium deposition. Along with reduced dentin thickness and root length in diabetic rats, the results revealed a significant increase in histone deacetylase 3 and 2 gene expressions in isolated diabetic pulp tissues compared to the control groups. The gene expression of odontogenic-related markers and alkaline phosphatase activity in human cultured pulp stem cells under hyperglycemic conditions significantly decreased. Adding Valproic acid and Trichostatin A restored the odontogenic differentiation markers, including calcium deposition, gene expression of dentin sialophosphoprotein, dentin matrix protein 1, and alkaline phosphatase activity. The data suggests that hyperglycemic conditions negatively impact the odontogenic potential of pulp mesenchymal stem cells. However, histone deacetylase inhibitors improve the impaired odontogenic differentiation capacity. This study implies that histone deacetylases may represent a potential therapeutic target for enhancing the regenerative mineralization of pulp cells in diabetic patients.

Analysis of multi-disease targeting effect of phytochemicals by AMPK stimulation– diabetes: A computational approach

Diabetes is a silent killer and a metabolic syndrome characterized by hyperglycemia that has been exponentially increasing in recent years. There is a need to develop therapeutic agents to control hyperglycemia and its secondary complications as well as protect and revive beta cells in diabetic patients. The target for first-line diabetes treatment is the adenosine monophosphate protein kinase (AMPK), which participates in cellular energy metabolism through phosphorylation of metabolic enzymes and transcription regulators. This study examined the drug-related properties as well as lead preparation of Catharanthus roseus alkaloids and testing molecular interaction at the AMPK targets to confirm their anti-diabetic effect. A control drug metformin and a library of 85 molecules of C. roseus alkaloids were crossed with the ADMET test, followed by the investigation of molecular interaction tested on AMPK1 and AMPK2 targets through an in silico docking process. Vindolinine (CID: 24148538), vindoline (CID: 425978), (+)-vindorosine (CID: 261578), Cr-1 (CID: 5315746), and Cr-2 (CID: 59908094) had passed the ADMET test. Molecular interaction of the tested C. roseus alkaloids on AMPK1 and AMPK2 targets had potential energy that varied from −7.4 to −5.3 kcal/mol, whereas binding energies of −4.0 kcal/mol for AMPK1-metformin interaction and −4.2 kcal/mol for AMPK2-metformin interaction were observed. The tested C. roseus alkaloids were shown to be more potent activators of AMPK than the control drug. All five biomolecules of C. roseus acted as modulators that have the potential to stimulate AMPK, reduce glucose production, and increase glucose utilization in hepatocytes. In addition, they diminished insulin resistance and secondary complications of diabetes by inhibiting acetyl-CoA carboxylase, regulating cholesterol levels and macrophage, and reviving beta cells in Type 2 diabetes. These results provided the foundation for developing new multi-disease-targeting drugs that can treat diabetes, obesity, cardiovascular disease, cancer, and other diseases by the stimulation of AMPK1 and AMPK2 targets.

Study of corneal endothelial cells in diabetic patients

Background: The cornea is the anterior transparent part of the eye. In addition to its optical and refractive function, it is an important protective structure.Aim: The aim of this study was to assess corneal endothelium (counts, morphology and structure) as well as corneal thickness of Type 2 diabetic participants.Setting: This is a hospital-based case–control study and was carried out at Ibn Al Haitham tertiary eye hospital in Baghdad, Iraq.Methods: The sample size was 240 eyes of 120 diabetic participants and 120 healthy participants. Non-contact specular microscopy was utilised to evaluate corneal endothelial cells, including endothelial cell density (ECD), coefficient of variation in cell area (CV), hexagonality (HEX) of cells as well as central corneal thickness (CCT).Results: The ECD was lower in the diabetic corneas (2584.87 ± 259.15 cell/mm2) compared with the healthy corneas (2717.56 ± 289.67 cell/mm2) (p = 0.017, statistically significant). Coefficient of variance (CV) was greater in the diabetic group (40.8 ± 4.17) as opposed to the group with healthy corneas (37.3 ± 2.89) (p = 0.019, statistically significant). The corneas of the diabetic group showed lower hexagonality (44.36% ± 9.87%) compared with the healthy corneas (59.35% ± 9.67%) (p 0.001, statistically significant). Furthermore, the corneas of the diabetic group had greater central thickness (581.1 ± 32.4 µm) when compared with the control group (511.8 ± 29.8 µm), (p 0.001, statistically significant). No correlation was found between the severity level of diabetic retinopathy and corneal endothelial pathological alterations.Conclusion: Long-term poorly controlled glycaemia has a remarkable impact on corneal endothelium (counts, morphology and structure) as well as corneal thickness.

Alteration of autophagy-related protein 5 (ATG5) levels and Atg5 gene expression in diabetes mellitus with and without complications.

BackgroundAutophagy is a catabolic mechanism that involves lysosomal-dependent degradation of unnecessary intracellular components and responsible for normal cellular homeostasis. Autophagy pathway and its key participant ATG5/LC3 are associated with several pathologies such as diabetes mellitus and its complications.MethodsLevels and expression of autophagy key components ATG5 and LC3B were analyzed in both human model and murine tissues. One hundred and twenty human subjects were divided into four groups: Healthy (control), diabetes mellitus without complications, diabetic nephropathy, and diabetic retinopathy. Additionally, we used kidneys from WT healthy and diabetic nephropathy mice. Lysate derived from human peripheral blood mononuclear cells and murine renal cortex lysates were subjected to western blot and immunohistochemical analysis.ResultsWestern blot and immunohistochemical analysis demonstrate that ATG5 protein levels were significantly decreased in diabetes mellitus, diabetic nephropathy (DN), and diabetic retinopathy patients versus healthy controls and in DN mice compared to healthy mice (0.65 ± 0.04; 1.15 ± 0.13 A.U. units, respectively). Quantification of staining area (%) of ATG5 mice tissue expression also decreased in DN versus healthy mice (4.42 ± 1.08%; 10.87 ± 1.01%, respectively).LC3B levels and expressionSignificant reduction in peripheral blood mononuclear cells in diabetic patients (with or without complications) vs. healthy controls. Renal LC3B levels were lower in DN versus healthy mice (0.36 ± 0.03; 0.68 ± 0.07 A.U. units). Renal LC3B staining quantification revealed significant reduction in DN versus healthy mice (1.7 ± 0.23%; 8.56 ± 1.7%).ConclusionWe conclude that ATG5, as well as LC3B, are down regulated in diabetic patients with or without complications. This diminution contributes to deficiencies in the autophagy process.

Efficacy and safety of intramuscular administration of allogeneic adipose tissue derived and expanded mesenchymal stromal cells in diabetic patients with critical limb ischemia with no possibility of revascularization: study protocol for a randomized controlled double-blind phase II clinical trial (The NOMA Trial)

BackgroundChronic lower limb ischemia develops earlier and more frequently in patients with type 2 diabetes mellitus. Diabetes remains the main cause of lower-extremity non-traumatic amputations. Current medical treatment, based on antiplatelet therapy and statins, has demonstrated deficient improvement of the disease. In recent years, research has shown that it is possible to improve tissue perfusion through therapeutic angiogenesis. Both in animal models and humans, it has been shown that cell therapy can induce therapeutic angiogenesis, making mesenchymal stromal cell-based therapy one of the most promising therapeutic alternatives. The aim of this study is to evaluate the feasibility, safety, and efficacy of cell therapy based on mesenchymal stromal cells derived from adipose tissue intramuscular administration to patients with type 2 diabetes mellitus with critical limb ischemia and without possibility of revascularization.MethodsA multicenter, randomized double-blind, placebo-controlled trial has been designed. Ninety eligible patients will be randomly assigned at a ratio 1:1:1 to one of the following: control group (n = 30), low-cell dose treatment group (n = 30), and high-cell dose treatment group (n = 30). Treatment will be administered in a single-dose way and patients will be followed for 12 months. Primary outcome (safety) will be evaluated by measuring the rate of adverse events within the study period. Secondary outcomes (efficacy) will be measured by assessing clinical, analytical, and imaging-test parameters. Tertiary outcome (quality of life) will be evaluated with SF-12 and VascuQol-6 scales.DiscussionChronic lower limb ischemia has limited therapeutic options and constitutes a public health problem in both developed and underdeveloped countries. Given that the current treatment is not established in daily clinical practice, it is essential to provide evidence-based data that allow taking a step forward in its clinical development. Also, the multidisciplinary coordination exercise needed to develop this clinical trial protocol will undoubtfully be useful to conduct academic clinical trials in the field of cell therapy in the near future.Trial registrationClinicalTrials.govNCT04466007. Registered on January 07, 2020. All items from the World Health Organization Trial Registration Data Set are included within the body of the protocol.

Safety and Efficacy of 2 Intracavernous Injections of Allogeneic Wharton’s Jelly-Derived Mesenchymal Stem Cells in Diabetic Patients with Erectile Dysfunction: Phase 1/2 Clinical Trial

Background and Objectives: Stem cell therapy is a novel treatment with regenerative ability that can treat erectile dysfunction (ED). This phase 1/2 clinical trial (NCT02945449) using 2 consecutive intracavernous (IC) injections of allogeneic Wharton’s jelly-derived mesenchymal stem cells (WJ-MSCs) was studied for the first time in the treatment of diabetic patients with ED. The primary outcome was to assess the safety and tolerability, and the secondary outcome was to assess the efficacy of 2 consecutive IC injections of allogeneic WJ-MSCs in diabetic ED. Patients and Methods: Twenty-two diabetic patients with refractory ED were included. Two consecutive IC injections of allogeneic WJ-MSCs were performed. Tolerability was assessed immediately, and at 24 h, safety was evaluated for 12 months. Efficacy was assessed using International Index of Erectile Function-5 (IIEF-5), Erection Hardness Score (EHS), and Color Duplex Doppler Ultrasound for 12 months. Results: The procedure was well-tolerated. Minimal and transient adverse events were redness and bruising at the site of injections. There were no patient-reported serious adverse effects. There were significant improvements in IIEF-5, EHS, peak systolic velocity (PSV) basal, and 20-min PSV, all over the follow-up time points in comparison to the baseline. Conclusion: This is the first human study with proven tolerability, safety, and efficacy of IC injections of allogeneic WJ-MSCs for the treatment of diabetic patients with ED.

Pseudoexfoliation syndrome in diabetic patients: transmission electron microscopy study of anterior lens epithelial cells.

Purpose: to examine the lens epithelial cells in diabetic patients with pseudoexfoliation to ultramicroscope and to compare the findings with those of patients without diabetes mellitus (DM) and/or without pseudoexfoliation (PEX).Materials and Methods: Forty patients aged 65-86 years were enrolled in the study. All patients had senile cataract and were divided into four groups of ten patients in each group. Group I: patients without pseudoexfoliation, without DM, Group II: without pseudoexfoliation, with DM, Group III: with pseudoexfoliation, without DM, Group IV (Pseudoexfoliation-Diabetic Group): with pseudoexfoliation, with DM. In all cases, part of the central portion of anterior lens capsule was removed during routine cataract surgery, and was properly prepared in order to be examined under a transmission electron microscope.Results: In the control group, mainly degenerative alterations to varying extents were observed. In all groups, intracellular and extracellular oedema, multilayering, apoptosis, completely destroyed cells adjacent to normal cellswere described. In the diabetic group, alterations were more severe with respect to group I. In PEX cases, the additionalirregularity of the epithelium surface, loose intercellular connection, as well as the loose connection between cells and basement membrane were described with the presence of PEX material free and within the basement membrane. In cases with PEX and DM, degenerative alterations and PEX material were observed as well, but the epithelium was better conserved compared to the PEX group.Conclusion: the observed lesions were more extended and more frequent in the pseudoexfoliation group, followed by the diabetic group. The pseudoexfoliation-diabetic group presented less intense modifications raising questions about the interaction of these different diseases.Abbreviations: DM = Diabetes Mellitus, PEX = Pseudoexfoliation, PXM = Pseudoexfoliative Material, AD = Alzheimer disease, TGF-β1 = Transforming Growth Factor beta 1, WHO = World Health Organization, LEC = Lens Epithelium Cells, BM = Basement Membrane, CM = Cytoplasmic Membrane

Cytomorphometric Analysis of Exfoliated Buccal Mucosal Cells in Diabetic Patients

Background: Diabetes mellitus is a common metabolic disease that causeschronic hyperglycemia and disturbance in carbohydrate, lipid and proteinmetabolism. It causes various changes in the cells of the oral mucosa, which canbe determined by exfoliative cytology. The aim of this study was to study theCytomorphometric alterations of exfoliated buccal mucosal cells in diabeticpatients and to establish an additional diagnostic tool in diabetic patients inChattogram area.
 Materials and methods: It was a cross-sectional comparative study carried outin the Department of Pathology, Chattogram Medical College, Chattogram. Oralsmears were obtained from 88 diabetic patients and 88 healthy individuals. Thesmears were stained with Papanicolaou solution. The cell diameter and nucleardiameter of 50 clearly defined cells were measured by multi-head microscope(OLYMPUS B51X). The cytoplasmic area and nucleus-cytoplasmic ratio werethen calculated. SPSS software (version 17) was used for statistical analysis ofthe study.
 Results: In the result, mean Cell Diameter (CD), Nuclear Diameter (ND),cytoplasmic diameter (CyD) and N/C ratio of diabetic patients and healthy werefound to be 250.29 ± 29.02 μm, 54.48 ± 4.03 μm, 195.81 ± 27.97 μm, 0.283 ±0.04 and 287.15 ± 25.23 μm, 47.41 ± 2.52 μm, 239.74 ± 24.45 μm, 0.199 ± 0.02.A statistically significant increase in ND & N/C ratio and decrease in CD &CyDwere observed in diabetic patients compared to control. In addition, it wasfound that age, sex, blood sugar level, duration and treatment history ofdiabetes do not affect the morphometric changes significantly.
 Conclusions: Result of this study suggests that diabetes produces definitemorphometric changes in the exfoliated buccal mucosal cells. Exfoliativecytology can be useful as an additional tool to aid in diagnosis of diabetesmellitus.
 Chatt Maa Shi Hosp Med Coll J; Vol.19 (1); January 2020; Page 3-7

12(S)-HETE mediates diabetes-induced endothelial dysfunction by activating intracellular endothelial cell TRPV1

Patients with diabetes develop endothelial dysfunction shortly after diabetes onset that progresses to vascular disease underlying the majority of diabetes-associated comorbidities. Increased lipid peroxidation, mitochondrial calcium overload, and mitochondrial dysfunction are characteristics of dysfunctional endothelial cells in diabetic patients. We here identified that targeting the lipid peroxidation product 12(S)-hydroxyeicosatetraenoic acid-induced [12(S)-HETE-induced] activation of the intracellularly located cation channel transient receptor potential vanilloid 1 (TRPV1) in endothelial cells is a means to causally control early-stage vascular disease in type I diabetic mice. Mice with an inducible, endothelium-specific 12/15-lipoxygenase (12/15Lo) knockout were protected similarly to TRPV1-knockout mice from type 1 diabetes-induced endothelial dysfunction and impaired vascular regeneration following arterial injury. Both 12(S)-HETE in concentrations found in diabetic patients and TRPV1 agonists triggered mitochondrial calcium influx and mitochondrial dysfunction in endothelial cells, and 12(S)-HETE effects were absent in endothelial cells from TRPV1-knockout mice. As a therapeutic consequence, we found that a peptide targeting 12(S)-HETE-induced TRPV1 interaction at the TRPV1 TRP box ameliorated diabetes-induced endothelial dysfunction and augmented vascular regeneration in diabetic mice. Our findings suggest that pharmacological targeting of increased endothelial lipid peroxidation can attenuate diabetes-induced comorbidities related to vascular disease.

The Correlation between Hemoglobin A1c (HbA1c) and Hyperreflective Dots (HRD) in Diabetic Patients.

Hyperreflective dots (HRD) are activated retinal microglial cells induced by retinal inflammation in diabetic patients. This study was conducted to compare the HRD count of normal and diabetic subjects; to determine the correlation between hemoglobin A1c (HbA1c) levels and HRD count; to determine HbA1c cut-off levels for the appearance of HRD in diabetic patients. A cross-sectional study was conducted among normal and diabetic patients. Fundus photos, SD-OCT images and HbA1c levels were taken. A total of 25 normal subjects, 32 diabetics without retinopathy and 26 mild-to-moderate nonproliferative diabetic retinopathy (NPDR) diabetics were recruited. There was a statistically significant difference between the mean count of HRD among the normal group, the diabetic without retinopathy group and the mild-to-moderate NPRD group. The mean HRD count in the inner retina layer was significantly higher compared to the outer retina layer. There was a significant linear relationship between the HbA1c levels and HRD count. Using the receiver operating curve, the HbA1c level of 5.4% was chosen as the cut-off point for the appearance of HRD. The positive linear correlation between the HbA1c levels and the appearance of HRD may indicate that hyperglycemia could activate retina microglial cells in diabetic patients.

Активация конечных протеинкиназ инсулинового сигнального каскада в мононуклеарных клетках периферической крови пациентов с диабетом и различными типами рака

Сигнальний шлях Akt/mTOR/p70S6K1 відіграє важливу роль у патогенезі раку та діабету. Макрофаги та лімфоцити беруть участь у патогенезі діабету, діабетичного атеросклерозу, формуванні резистентності до інсуліну, а також імунної відповіді на рак та підтримці пухлини. Метою дослідження було вивчення активації Akt/mTOR/p70S6K1 у мононуклеарних клітинах периферичної крові (РВМС) пацієнтів із цукровим діабетом 2-го типу (T2D) і раком. Результати. Рівень інсуліну в крові діабетичних пацієнтів із раком молочної залози та ендометрія був значно вищим порівняно з контролем, але не відрізнявся від контролю в крові діабетичних пацієнтів із коло- ректальним раком і раком підшлункової залози. Найвищий рівень інсуліну спостерігався в крові пацієнтів із T2D. Майже таку ж картину спостерігали відносно концентрації IGF‑1 у крові. Фосфорилювання S473 в Akt кіназою mTORC2 було вищим від контрольних значень у РВМС пацієнтів із діабетом і раком молочної залози та ендометрія. Рівень фосфорилювання Akt у PBMC у пацієнтів із діабетом і колоректальним раком та раком підшлункової залози був нижчим від такого в контрольних клітинах, що відповідає концентраціям інсуліну та IGF‑1 у крові. Активації Akt mTORC2 у PBMC пацієнтів із діабетом не спостерігалося. У PBMC пацієнтів із раком і діабетом не відбувалося активації mTORC1, але спостерігали значну його активацію в клітинах пацієнтів із T2D. Імовірно, активацію Akt mTORC2 не пов’язано з активацією mTORC1 у клітинах пацієнтів із T2D. Зниження активності mTORC1 відбувалося в клітинах хворих на діабет з усіма досліджуваними типами раку. Можна припустити, що пов’язаний із діабетом сигналінг PI3K/Akt у PBMC, імовірно, інтерферує з механізмами передачі сигналів, пов’язаних із раком. Відзначено відмінності в онкологічних пацієнтів із T2D і раком молочної залози/ендометрія та раком підшлункової залози/кишечника з оглядуна вміст IGF/інсуліну в крові й активацію Akt у PMBC, що можна пояснити специфічним гормональним тлом перших двох типів раку. Висновок. Обговорюється гіпотеза щодо реципрокного фосфорилювання Akt комплексами PDK1 і mTORC2 по T308 і S473 відповідно.

Effect of negative-pressure wound therapy on the circulating number of peripheral endothelial progenitor cells in diabetic patients with mild to moderate degrees of ischaemic foot ulcer.

Objective To investigate the effect of negative-pressure wound therapy (NPWT) on the circulating number of endothelial progenitor cells (EPCs) in diabetic patients with mild to moderate degrees of ischemic foot ulcer. Methods We selected 84 diabetic patients who had a foot ulcer with a duration of at least four weeks and who had an ankle-brachial index of 0.5–0.9. Patients were assigned to one two groups according to 2:1 randomization: NPWT group ( n = 56) and non-NPWT (patients who did not receive NPWT) group ( n = 28). The control group (NC group) was composed of 18 patients who had normal glucose tolerance and lower extremity ulcer without arteriovenous disease. NPWT was performed on the ulcer after debridement for one week for patients in both the NPWT group and the NC group, and the patients in the non-NPWT group received conventional treatment process. The circulating number of EPCs was measured before and after various treatments, and the factors influencing their changes were analysed. Results After NPWT, the circulating number of EPCs significantly increased in both the NPWT group and the NC group ((85.3 ± 18.1) vs. (34.1 ± 12.5)/106 cells; (119.9 ± 14.4) vs. (66.1 ± 10.6)/106 cells, both P < 0.05). In contrast, the circulating number of EPCs had no significant change in the non-NPWT group ((45.2 ± 19.4) vs. (34.7 ± 16.8)/106 cells, P > 0.05). In addition, the circulating levels of vascular endothelial growth factor (VEGF) and the protein expressions of VEGF and stromal cell-derived factor-1α (SDF-1α) in the granulation tissue significantly increased after NPWT in both the NPWT and the NC group, but there was no significant change in the non-NPWT group. Compared with the non-NPWT group, the changes in VEGF and SDF-1α levels in the sera and granulation tissue were all significantly higher in both the NPWT and NC groups ( P < 0.05, P < 0.01, respectively). There was no significant difference in changes in the circulating number of EPCs in the peripheral blood and levels of VEGF and SDF-1α in the sera and granulation tissue between the NPWT and NC groups. Correlation analysis showed that the change in the circulating number of EPCs was correlated with the changes of VEGF and SDF-1α levels in the sera and granulation of the NPWT and NC groups ( P < 0.05). Conclusion NPWT may increase the circulating number of EPCs in diabetic patients with mild to moderate ischaemic foot ulcer as in non-diabetic controls, which may be attributed to the upregulation of systemic and local VEGF and SDF-1α levels.

Stem Cell-Based Therapies: A New Ray of Hope for Diabetic Patients.

Diabetes and its complications are a significant health concern throughout the globe. There are physiological differences in the mechanism of type-I and type-II diabetes and the conventional drug therapy as well as insulin administration seem to be insufficient to address the problem at large successfully. Hypoglycemic swings, frequent dose adjustments and resistance to the drug are major problems associated with drug therapy. Cellular approaches through stem cell based therapeutic interventions offer a promising solution to the problem. The need for pancreatic transplants in case of Type- I diabetes can also be by-passed/reduced due to the formation of insulin producing β cells via stem cells. Embryonic Stem Cells (ESCs) and induced Pluripotent Stem Cells (iPSCs), successfully used for generating insulin producing β cells. Although many experiments have shown promising results with stem cells in vitro, their clinical testing still needs more exploration. The review attempts to bring into light the clinical studies favoring the transplantation of stem cells in diabetic patients with an objective of improving insulin secretion and improving degeneration of different tissues in response to diabetes. It also focuses on the problems associated with successful implementation of the technique and possible directions for future research.

Restoring vasculogenic potential of endothelial cells from diabetic patients through spheroid formation.

Diabetes is an emerging epidemic in the developing world and represents a major risk factor for cardiovascular disease. Among other issues, patients with diabetes suffer from diminished endothelial cell (EC) function, which contributes to impaired vasculogenesis and recovery from ischemic insult. The formation of cells into three-dimensional spheroids promotes cell survival and activates key signaling pathways through the upregulation of cell-cell contacts, providing an opportunity to overcome shortcomings associated with individual autologous cells. We hypothesized that forming human microvascular endothelial cells (HMVECs) from diabetic patients into spheroids would restore their vasculogenic potential following upregulation of these cell-cell interactions. HMVEC spheroids were formed and suspended in fibrin gels to quantify vasculogenic potential. Individual HMVECs from diabetic patients exhibited similar proliferative and chemotactic potential to cells from healthy donors but reduced tubulogenesis. HMVEC spheroids formed from diabetic donors formed more sprouts than spheroids from healthy donors, and more sprouts than individual cells from either population. Compared to cells from healthy donors, sprout formation was more efficiently abrogated in HMVECs from diabetic patients by blocking matrix metalloproteinase activity. This study demonstrates a promising approach for restoring the diminished vasculogenic potential of endothelial cells in diabetic patients.

Proliferative Capacity and Differentiation Potential of Isolated Postnatal Human Dental Pulp Stem Cells in Diabetic Patients

Stem cells are characterized by the ability to form clones, self-regenerate and differentiate into different types of cells. Stem cells derived from human dental pulp (DPSCs) have been shown to differentiate into odontoblasts in vitro after using Bone Morphogenic Protein -2 (BMP-2). The aim of the present study was to explore the variations in the differentiation potential of the DPSC into odontoblasts in diabetic adults; it also aimed at investigating the possible influence of the origin of stem cells (coronal and radicular pulp) on their differentiation potential. Pulp tissue was extirpated from healthy individuals as well as from controlled and uncontrolled diabetic patients. Pulp tissue was divided into coronal and radicular parts and each were cultured for 30 days and then BMP-2 was added. Alizarin red staining was performed to confirm mineralization. RT-PCR was used to analyse expression of mineralization markers Dentin sialophosphoprotein (DSPP) & Enamelysin. The results of this study showed that DPSCs of both healthy and diabetic groups had stem cell properties. DPSCs of the coronal pulp have a more proliferative capacity than that of the radicular pulp. Controlled diabetes mellitus provides relatively unfavourable conditions for the DPSCs to proliferate and differentiate while uncontrolled diabetes produces more deleterious effect on the DPSCs capacity for proliferation and differentiation. Expression of DSPP and enamelysin was positive in healthy and controlled diabetics groups, while in the uncontrolled diabetic group it was negative. It is concluded that DPSCs of the coronal pulp have a more proliferative capacity than that of the radicular pulp, controlled diabetes mellitus provides relatively unfavourable conditions for the DPSCs to proliferate and differentiate and uncontrolled diabetes produces more deleterious effect on the DPSCs capacity for proliferation and differentiation.

Effects of Hypoglycemia on Circulating Stem and Progenitor Cells in Diabetic Patients.

Iatrogenic hypoglycemia is the most common acute diabetic complication, and it significantly increases morbidity. In people with diabetes, reduction in the levels of circulating stem and progenitor cells predicts adverse outcomes. To evaluate whether hypoglycemia in diabetes affects circulating stem cells and endothelial progenitor cells (EPCs). We performed an experimental hypoglycemia study (Study 1) and a case-control study (Study 2). Tertiary referral inpatient clinic. Type 1 diabetic patients (Study 1, n = 19); diabetic patients hospitalized for severe iatrogenic hypoglycemia, matched inpatient and outpatient controls (Study 2, n = 22/group). Type 1 diabetic patients underwent two in-hospital sessions of glucose monitoring during a breakfast meal with or without induction of hypoglycemia in random order. In Study 2, patients hospitalized for hypoglycemia and matched controls were compared. Circulating stem cells and EPCs were measured by flow cytometry based on the expression of CD34 and kinase insert domain receptor (KDR). In Study 1, the physiologic decline of CD34+KDR+ EPCs from 8 am to 2 pm was abolished by insulin-induced hypoglycemia in type 1 diabetic patients. In Study 2, diabetic patients hospitalized for severe iatrogenic hypoglycemia had significantly lower levels of CD34+ stem cells and CD34+KDR+ EPCs compared with diabetic inpatients or outpatient controls. In diabetic patients, a single mild hypoglycemic episode can compromise the physiologic EPC fluctuation, whereas severe hypoglycemia is associated with a marked reduction in stem cells and EPCs. These data provide a possible link between hypoglycemia and adverse outcomes of diabetes.

Periodontal treatment modulates gene expression of endothelial progenitor cells in diabetic patients.

Periodontitis is closely linked with type 2 diabetes mellitus (T2DM) and endothelial dysfunction. This study investigated the effects of periodontal treatment on immuno-inflammatory gene expression of endothelial progenitor cells (EPCs) in diabetic patients. Eighteen T2DM patients with moderate to severe chronic periodontitis were randomly assigned to the Treatment group with oral hygiene instruction (OHI), scaling and root debridement (n=11), and Control group (n=7) with OHI alone. Peripheral blood samples were taken for biochemical analysis and culture of EPCs at baseline and 6months after the treatment. PCR array-based profiling of 84 Toll-like receptor signalling-related genes in EPCs was firstly assessed for four randomly selected patients from the Treatment group. The differentially expressed genes were then further validated by qPCR in both groups. All subjects in the Treatment group significantly improved their periodontal conditions. Among the 84 genes tested, IL-6 and IL-8 transcripts were significantly downregulated with over twofold change after the treatment, and this observation was further validated by qPCR in all subjects from both groups (p<.05). This preliminary study suggests that periodontal treatment may contribute to a notable reduction in immuno-inflammatory gene expression measured by IL-6 and IL-8 transcripts in EPCs.