Responses of Endothelial Progenitor Cells to Chronic and Acute Physical Activity in Healthy Individuals.

Endothelial progenitor cells (EPCs) are circulating cells of various origins that possess the capacity for renewing and regenerating the endothelial lining of blood vessels. During physical activity, in response to factors such as hypoxia, changes in osmotic pressure, and mechanical forces, endothelial cells undergo intense physiological stress that results in endothelial damage. Circulating EPCs participate in blood vessel repair and vascular healing mainly through paracrine signalling. Furthermore, physical activity may play an important role in mobilising this important cell population. In this narrative review, we summarise the current knowledge on the biology of EPCs, including their characteristics, assessment, and mobilisation in response to both chronic and acute physical activity in healthy individuals.

Physical Activity as a Modern Intervention in the Fight against Obesity-Related Inflammation in Type 2 Diabetes Mellitus and Gestational Diabetes.

Diabetes is one of the greatest healthcare problems; it requires an appropriate approach to the patient, especially when it concerns pregnant women. Gestational diabetes mellitus (GDM) is a common metabolic condition in pregnancy that shares many features with type 2 diabetes mellitus (T2DM). T2DM and GDM induce oxidative stress, which activates cellular stress signalling. In addition, the risk of diabetes during pregnancy can lead to various complications for the mother and foetus. It has been shown that physical activity is an important tool to not only treat the negative effects of diabetes but also to prevent its progression or even reverse the changes already made by limiting the inflammatory process. Physical activity has a huge impact on the immune status of an individual. Various studies have shown that regular training sessions cause changes in circulating immune cell levels, cytokine activation, production and secretion and changes in microRNA, all of which have a positive effect on the well-being of the diabetic patient, mother and foetus.

A Role for Advanced Glycation End Products in Molecular Ageing.

Ageing is a composite process that involves numerous changes at the cellular, tissue, organ and whole-body levels. These changes result in decreased functioning of the organism and the development of certain conditions, which ultimately lead to an increased risk of death. Advanced glycation end products (AGEs) are a family of compounds with a diverse chemical nature. They are the products of non-enzymatic reactions between reducing sugars and proteins, lipids or nucleic acids and are synthesised in high amounts in both physiological and pathological conditions. Accumulation of these molecules increases the level of damage to tissue/organs structures (immune elements, connective tissue, brain, pancreatic beta cells, nephrons, and muscles), which consequently triggers the development of age-related diseases, such as diabetes mellitus, neurodegeneration, and cardiovascular and kidney disorders. Irrespective of the role of AGEs in the initiation or progression of chronic disorders, a reduction in their levels would certainly provide health benefits. In this review, we provide an overview of the role of AGEs in these areas. Moreover, we provide examples of lifestyle interventions, such as caloric restriction or physical activities, that may modulate AGE formation and accumulation and help to promote healthy ageing.

Plasma Levels of Interleukins 36α, 36ß, and 37 in Patients with Psoriasis and Their Correlation with Disease Activity Parameters.

Psoriasis is a chronic, proliferative, inflammatory skin disease characterised by skin lesions and systemic symptoms. Numerous cytokines are produced in psoriasis as a result of inflammation. The aim of this study was to examine the plasma concentrations of IL-36α, IL-36ß, and IL-37 in psoriasis and their correlations with disease activity parameters. This study recruited 84 individuals, 53 with plaque-type psoriasis and 31 healthy controls. The plaque type of psoriasis is the most common type and is typically characterized by circular-to-oval red plaques distributed over body surfaces of the extremities and scalp. In patients with psoriasis, we observed statistically significantly decreased plasma concentrations of IL-36ß and IL-37. The concentrations of IL-36α were increased in comparison with control group. The plasma concentrations of IL-36α and IL-36ß were statistically significantly correlated with all tested parameters of disease activity: the Psoriasis Activity Severity Index, Dermatology Life Quality Index, and Body Surface Area Index. There were no statistically significant correlations between plasma levels of IL-37 and the tested parameters of disease activity. These results indicate a role of IL36α, IL-36ß, and IL-37 in the pathogenesis of psoriasis.

Epigenetic Alterations in Sports-Related Injuries.

It is a well-known fact that physical activity benefits people of all age groups. However, highly intensive training, maladaptation, improper equipment, and lack of sufficient rest lead to contusions and sports-related injuries. From the perspectives of sports professionals and those performing regular-amateur sports activities, it is important to maintain proper levels of training, without encountering frequent injuries. The bodily responses to physical stress and intensive physical activity are detected on many levels. Epigenetic modifications, including DNA methylation, histone protein methylation, acetylation, and miRNA expression occur in response to environmental changes and play fundamental roles in the regulation of cellular activities. In the current review, we summarise the available knowledge on epigenetic alterations present in tissues and organs (e.g., muscles, the brain, tendons, and bones) as a consequence of sports-related injuries. Epigenetic mechanism observations have the potential to become useful tools in sports medicine, as predictors of approaching pathophysiological alterations and injury biomarkers that have already taken place.

Adiponectin Is a Component of the Inflammatory Cascade in Rheumatoid Arthritis.

Adiponectin is a secretory protein of adipocytes that plays an important role in pathological processes by participation in modulating the immune and inflammatory responses. The pro-inflammatory effect of adiponectin is observed in rheumatoid arthritis (RA). In this study, we examined adiponectin plasma levels and the expression of adiponectin in bone marrow tissue samples, synovium samples, and infrapatellar fat pad samples from patients with osteoarthritis (OA) and RA. Additionally we examined the expression of adiponectin receptors AdipoR1 and AdipoR2 in synovium samples and infrapatellar fat pad samples from patients with OA and RA. We also assessed the correlations between adiponectin plasma concentrations, adiponectin expression in bone marrow, synovium, infrapatellar fat pad, and plasma levels of selected cytokines. We found increased expression of adiponectin in synovium samples and infrapatellar fat pad samples from patients with RA as compared to patients with OA. There were no statistically significant differences of adiponectin plasma levels and adiponectin expression in bone marrow tissue samples between OA and RA patients. There were no differences in the expression of AdipoR1 and AdipoR2 at the mRNA level in synovial tissue and the infrapatellar fat pad between RA and OA patients. However, in immunohistochemical analysis in samples of the synovial membrane from RA patients, we observed very strong expression of adiponectin in intima cells, macrophages, and subintimal fibroblasts, such as synoviocytes, vs. strong expression in OA samples. Very strong expression of adiponectin was also noted in adipocytes of Hoffa's fat pad of RA patients. Expression of AdipoR1 was stronger in RA tissue samples, while AdipoR2 expression was very similar in both RA and OA samples. Our results showed increased adiponectin expression in the synovial membrane and Hoffa's pad in RA patients compared to that of OA patients. However, there were no differences in plasma adiponectin concentrations and its expression in bone marrow. The results suggest that adiponectin is a component of the inflammatory cascade that is present in RA. Pro-inflammatory factors enhance the expression of adiponectin, especially in joint tissues-the synovial membrane and Hoffa's fat pad. In turn, adiponectin also increases the expression of further pro-inflammatory mediators.

Short-Term Functional Outcomes of Short Femoral Neck Stems Are the Same as Those of Conventional Stems in Primary Total Hip Arthroplasty.

(1) Background: In this study, two types of implants were compared-a conventional hip stem and a femoral neck prosthesis. (2) Methods: The femoral neck prosthesis study group included 21 patients, while the conventional hip stem control group was 40 patients. The first examination was the pre-op check, while the next ones were performed 6 weeks, 1 year, and 3 years after surgery. The Harris Hip Score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Oxford Hip Score (OHS), University of California at Los Angeles Activity Score (UCLA), and Visual Analog Scale EQ (VAS EQ) forms were completed at each clinical study visit. (3) Results: The HHS in the femoral neck prosthesis group and the conventional hip stem group 6 weeks after surgery was 68.8 ± 16.47 and 67.6 ± 8.92, respectively, and 1 year after surgery, this was 93 ± 5.58 vs. 90.6 ± 5.17, respectively. The OHS of the femoral neck prosthesis group was 34.8 points after 6 weeks, 45.5 points after 1 year, and 43.9 points after 3 years. The respective values in the conventional hip stem group were 35.5, 41.55, and 42.13 points. The WOMAC values for the femoral neck prosthesis group were 70.6, 92.7, and 86 points, respectively, while for the conventional hip stem group, they were 74, 88.1, and 86.1 points. The UCLA scores recorded in the conventional hip stem group ranged from 3.15 to 5.05 points, but a higher mean value of 5.33 points was obtained in the femoral neck prosthesis group. VAS EQ was equal to 84 points three years after the operation. (4) Conclusions: The study showed no significant differences in the functional scores of both groups, and the new type of cervical femoral stem could be the first choice in younger patients.

Impact of Selected Serum Factors on Metastatic Potential of Gastric Cancer Cells.

(1) Background: stromal-derived factor-1 (SDF-1/CXCL12), hepatocyte and vascular-endothelial growth factors (HGF and VEGF) have been shown to facilitate cell motility, proliferation and promote local tumor progression and metastatic spread. Recent research shows the important role of these cytokines in gastric cancer (GC) progression. (2) Methods: 21 gastric cancer patients and 19 healthy controls were included in the study. SDF-1, HGF and VEGF levels were evaluated in sera by ELISA. Patients and control sera were used to stimulate CRL-1739 GC cell line, and chemotaxis, adhesion and proliferation potential were assessed. (3) Results: Concentrations of SDF-1, HGF and VEGF were significantly higher in patients than in controls. Chemotaxis and adhesion assays revealed a significant response of GC cells to patients' serum. Furthermore, significant relationships were seen between chemotactic/adhesion response and tumor stage. Serum from intestinal early GC patients produced significantly stronger chemotactic response when compared to patients with metastatic spread. In turn, serum from patients with distal metastases significantly increased the adhesion of GC cells when compared to sera from the patients with no distal metastases. We also observed that HGF strongly stimulated the proliferation of CRL-1739 cells. (4) Conclusions: We observed that the sera from GC patients, but also SDF-1, HGF and VEGF used alone, have a strong pro-metastatic effect on CRL-1739 cells. We also demonstrated that the concentration of these cytokines is specifically elevated in the sera of patients in an early stage of malignancy. Our results indicate that SDF-1, HGF and VEGF are very important molecules involved in gastric cancer progression.

Protein Arginine Methyltransferase (PRMT) Inhibitors-AMI-1 and SAH Are Effective in Attenuating Rhabdomyosarcoma Growth and Proliferation in Cell Cultures.

Rhabdomyosarcoma (RMS) is a malignant soft tissue cancer that develops mostly in children and young adults. With regard to histopathology, four rhabdomyosarcoma types are distinguishable: embryonal, alveolar, pleomorphic and spindle/sclerosing. Currently, increased amounts of evidence indicate that not only gene mutations, but also epigenetic modifications may be involved in the development of RMS. Epigenomic changes regulate the chromatin architecture and affect the interaction between DNA strands, histones and chromatin binding proteins, thus, are able to control gene expression. The main aim of the study was to assess the role of protein arginine methyltransferases (PRMT) in the cellular biology of rhabdomyosarcoma. In the study we used two pan-inhibitors of PRMT, called AMI-1 and SAH, and evaluated their effects on proliferation and apoptosis of RMS cells. We observed that AMI-1 and SAH reduce the invasive phenotype of rhabdomyosarcoma cells by decreasing their proliferation rate, cell viability and ability to form cell colonies. In addition, microarray analysis revealed that these inhibitors attenuate the activity of the PI3K-Akt signaling pathway and affect expression of genes related to it.

Lead (Pb) Accumulation in Human THP-1 Monocytes/Macrophages In Vitro and the Influence on Cell Apoptosis.

In this study, we investigated the ability of THP-1 monocytes and macrophages to accumulate lead (Pb) in vitro, relative to Pb concentration and length of exposure. Moreover, we also evaluated the effect of Pb accumulation on cell viability and apoptosis. THP-1 monocytes and macrophages were cultured in the presence of Pb at 1.25 µg/dL, 2.5 µg/dL, 5 µg/dL, and 10 µg/dL. Pb accumulation was examined by inductively coupled plasma and confocal microscopy. The influence of Pb on cell viability, apoptosis, and necrosis was assessed using flow cytometry. The results showed that Pb was toxic to THP-1 monocytes/macrophages even at very low environmental concentrations. Despite the use of low concentrations, both monocytes and macrophages showed dose-dependent and time-dependent decreases in viability, with a simultaneous increase in the percentage of early and late apoptotic cells. Macrophages reacted more strongly to Pb than monocytes. When exposed to the same Pb concentrations, they showed lower viability and a higher percentage of necrotic cells. The incubation time positively correlated with Pb accumulation in a dose-dependent manner. The obtained results indicate that environmental exposure to low Pb concentrations may significantly impair the function of macrophages, with the increased number of apoptotic cells potentially contributing to the development of many pathologies in the brain and whole body.

Extracellular Adenine Nucleotides and Adenosine Modulate the Growth and Survival of THP-1 Leukemia Cells.

A new approach to improve the effectiveness of acute myeloid leukemia (AML) treatment is to use the properties of purinergic signaling molecules secreted into the bone marrow milieu in response to leukemic cell growth. Therefore, our study aimed to evaluate the effects of extracellular adenine nucleotides and adenosine on the growth and death parameters in the leukemic THP-1 cell line. Cells were exposed to ATP, ADP, AMP, adenosine and nonhydrolyzable analogues of ATP and ADP (ATPγS and ADPßS) in a 1-1000 µM broad concentration range. The basal mRNA expression of the P1 and P2 receptors was evaluated by real-time PCR. Changes in the processes of cell growth and death were assessed by flow cytometry analysis of proliferation, cell cycle and apoptosis. Chemotaxis toward stromal cell-derived factor-1 (SDF-1) was performed using the modified Boyden chamber assay, and chemokine receptor type 4 (CXCR4) surface expression was quantified by flow cytometry. We indicated several antileukemic actions. High micromolar concentrations (100-1000 µM) of extracellular adenine nucleotides and adenosine inhibit the growth of cells by arresting the cell cycle and/or inducing apoptosis. ATP is characterized by the highest potency and widest range of effects, and is responsible for the cell cycle arrest and the apoptosis induction. Compared to ATP, the effect of ADP is slightly weaker. Adenosine mostly has a cytotoxic effect, with the induction of apoptosis. The last studied nucleotide, AMP, demonstrated only a weak cytotoxic effect without affecting the cell cycle. In addition, cell migration towards SDF-1 was inhibited by low micromolar concentrations (10 µM). One of the reasons for this action of ATPγS and adenosine was a reduction in CXCR4 surface expression, but this only partially explains the mechanism of antimigratory action. In summary, extracellular adenine nucleotides and adenosine inhibit THP-1 cell growth, cause death of cells and modulate the functioning of the SDF-1/CXCR4 axis. Thus, they negatively affect the processes that are responsible for the progression of AML and the difficulties in AML treatment.

Differential effect of adenosine on rhabdomyosarcoma migration and proliferation.

INTRODUCTION: Adenosine and its receptors are involved deeply in the regulation of tumour biology. Purine nucleotides are released from stressed cells in states of hypoxia or radiochemotherapy-induced cell damage. Adenosine exerts its effect through the P1 family of selective receptors. The purpose of the study was to evaluate the exact role of extracellular role on biology of Rhabdomyosarcoma (RMS) cells. MATERIAL AND METHODS: Series of in vitro studies accompanied by immunohistochemical, RQ-PCR and shRNA methods have characterised adenosine receptor expression on Rhabdomyosarcoma cell lines, normal skeletal muscle and effect of adenosine on Rhabdomyosarcoma growth and migration. RESULTS: Extracellular adenosine (highest at 50 µM, p < 0.05) and AMP (highest at 300 µM, p < 0.05) markedly enhanced chemotaxis in the Boyden chamber assay The reaction is mostly governed by the A1 receptor, which is greatly overexpressed in Rhabdomyosarcoma as compared with normal skeletal muscle. Cell migration induced by adenosine and AMP is blocked by pertussis toxin, phospholipase C and MAP kinase inhibitor, which demonstrates the importance of these signalling pathways. High doses of adenosine have a detrimental effect on cellular proliferation, in a receptor-independent manner (≥ 500 µM; p < 0.05). The blockage of adenosine transporter by dipyridamole abolishes this effect, indicating involvement of an intrinsic pathway. Further increase of adenosine concentration, induced by deaminase inhibitors, augment the effect. CONCLUSIONS: Our results suggest that adenosine and AMP trigger cell migration by binding to P1 receptors and directing cancer cells to the sites of hypoxia or cellular damage. Specifically by A1 receptor which is overexpressed in RMS.

‬The expression of purinergic P2X4 and P2X7 receptors in selected mesolimbic structures during morphine withdrawal in rats.

Morphine is one of the most potent analgesics used in medicine and it's long-term use is associated with the risk of the state of dependence. The cessation of chronic morphine administration leads to withdrawal signs which are associated with neurotransmitter dysregulations within mesolimbic system. Adenosine 5'-triphosphate (ATP) and purinergic system play an important role in the activity of central nervous system (CNS). Purinergic receptors are widely distributed in neurons and glial cells throughout the CNS taking part in integration of functional activity between neurons, glial and vascular cells. In the present study the mRNA and protein expression of purinergic P2X4 and P2X7 receptors in selected mesolimbic structures (striatum, hippocampus and prefrontal cortex) during morphine withdrawal in rats was investigated by RT-PCR and Western Blot analysis. Two experimental models of morphine withdrawal were studied: single and repeated morphine withdrawal. We demonstrated that expression of P2X4 and P2X7 receptors was altered during morphine withdrawal period in rats. These alterations were varied in particular mesolimbic areas depending on the scheme of morphine administration. Our results extend the current knowledge on morphine withdrawal and for the first time high-light interactions between purinergic system and morphine withdrawal. It seems, the purinergic system may be a new, valuable tool in searching for a new strategy of management of opioid dependence.

Connexin 43 expression in the testes during postnatal development of finasteride-treated male rat offspring.

INTRODUCTION: Hormone-dependent events that occur throughout the first wave of spermatogenesis, such as cellular communication within seminiferous epithelium during early postnatal testis maturation, are important for adult male fertility. Any changes in the T/DHT ratio in male progeny born from females fertilized by finasteride-treated male rats can result in impairment of testicular physiology. The aim of the study was to verify whether finasteride has a transgenerational effect on the expression of connexin 43 (Cx43), a gap junction protein in testes of the F1 generation. MATERIAL AND METHODS: The subjects of the study were 7, 14, 21/22, 28, and 90-day-old Wistar male rats born by females fertilized by finasteride-treated rats (F1:Fin). The offspring born by untreated rats were used as controls (F1:Control). Connexin 43 was evaluated in the seminiferous epithelium by immunohistochemistry, and in the testis homogenates by Western blot and qRT-PCR. The Cx43 mRNA and protein expression was correlated with intratesticular levels of T and DHT by Spearman's rank correlation coefficient. RESULTS: We observed a difference in the Cx43 expression in the testis of male rats born by female rats fertilized by finasteride-treated male rats, as compared to the control on following PND (7, 22 and 28 PND, p < 0.001; 14 PND, p < 0.01); and a strong, positive correlation between Cx43 with DHT was only in the F1:Fin group (mRNA: rs = +0.51, p = 0.004; protein: rs = +0.54, p = 0.002). CONCLUSIONS: Finasteride treatment of male adult rats may cause changes in the communication between the testicular cells of their offspring, leading to a defective course of spermatogenesis.

Comparative evaluation of new dihydropyrimidine and dihydropyridine derivatives perturbing mitotic spindle formation.

AIM: The mitotic spindle plays a key role in cell division which makes it an important target in cancer therapy. In the present study the antiproliferative activity of 4-benzyl-5-phenyl-3,4-dihydropyrimidine-2(1H)-thione (1) and its pyridine bioisoster (2) were evaluated and compared with monastrol (MON), the first known cell-permeable small molecule which disrupts bipolar spindle formation by inhibiting Eg5-kinesin activity. RESULTS: Our data revealed that compound 2 showed higher antiproliferative activity than MON against MCF7 and A375 cell lines and comparable reversible cell cycle inhibition in G2/M phase. However, compound 2 produced distinct phenotype from monoastral spindles, and did not affect Eg5 ATPase activity. CONCLUSION: The activity of compound 2 may suggest its new promising anticancer mechanism (different than MON), targeting other component required for spindle bipolarity.

Plasma concentration of urokinase plasminogen activator receptor is a marker of kidney allograft function.

BACKGROUND: Urokinase-type plasminogen activator receptor (uPAR) is found in a variety of cell types including monocytes, lymphocytes, macrophages, and endothelial cells and plays an important role in fibrinolysis and in the activation and chemotaxis of neutrophils and lymphocytes. In this study, we examined the correlation between uPAR plasma concentration and kidney allograft function. AIMS: This study enrolled 78 Caucasian deceased-donor renal transplant recipients. METHODS: Plasma concentrations of uPAR were measured using commercially available enzyme-linked immunosorbent assay (ELISA) kits. RESULTS: We observed elevated with borderline significance (p = 0.095) uPAR plasma concentrations in patients with tubular atrophy. Plasma concentrations of uPAR showed strong statistically significant positive correlations with serum creatinine or urea and strong negative correlation with estimated glomerular filtration rate (eGFR). There was also a borderline positive correlation between uPAR plasma concentration and protein concentration in urine as well as the duration of hemodialysis. CONCLUSIONS: The results of our study indicate that uPAR plasma concentrations in kidney allograft recipients are significantly negatively correlated with graft function and may be elevated in patients with tubular atrophy.

Picropodophyllin (PPP) is a potent rhabdomyosarcoma growth inhibitor both in vitro and in vivo.

BACKGROUND: Insulin-like growth factors and insulin are important factors promoting cancer growth and metastasis. The molecules act through IGF1 (IGF1R) and insulin (InsR) receptors. Rhambodmyosarcomas (RMS) overproduce IGF2 - a potent ligand for IGF1R and, at the same time, highly express IGF1 receptor. The purpose of the study was to evaluate possible application of picropodophyllin (PPP) - a potent IGF1R inhibitor. METHODS: In our study we used a number of in vitro assays showing influence of IGF1R blockage on RMS cell lines (both ARMS and ERMS) proliferation, migration, adhesion, cell cycling and signal transduction pathways. Additionally, we tested possible concomitant application of PPP with commonly used chemotherapeutics (vincristine, actinomycin-D and cisplatin). Moreover, we performed an in vivo study where PPP was injected intraperitoneally into RMS tumor bearing SCID mice. RESULTS: We observed that PPP strongly inhibits RMS proliferation, chemotaxis and adhesion. What is more, application of the IGF1R inhibitor attenuates MAPK phosphorylation and cause cell cycle arrest in G2/M phase. PPP increases sensitivity of RMS cell lines to chemotherapy, specifically to vincristine and cisplatin. In our in vivo studies we noted that mice treated with PPP grew smaller tumors and displayed significantly decreased seeding into bone marrow. CONCLUSIONS: The cyclolignan PPP effectively inhibits RMS tumor proliferation and metastasis in vitro and in an animal model.

COX2 and NOS3 gene polymorphisms in women with gestational diabetes.

BACKGROUND: Gestational diabetes (GDM) is carbohydrate intolerance occurring in pregnancy. Low-grade inflammation plays an important role in the pathogenesis of this disorder. The present study aimed to examine the association between COX2 (rs6681231) and NOS3 (rs1799983 and rs2070744) gene polymorphisms and GDM. METHODS: The study included 204 pregnant women with GDM and 207 pregnant women with normal glucose tolerance. The diagnosis of GDM was based on a 75-g oral glucose tolerance test at 24-28 weeks of gestation. RESULTS: We observed an increased frequency of COX2 rs6681231 CC and GC genotype carriers among women with GDM (CC + GC versus GG, odds ratio = 1.55, 95% confidence interval = 1.01-2.36, p = 0.043; C versus G, odds ratio = 1.59, 95% confidence interval = 1.10-2.30, p = 0.013). There were no statistically significant differences in the distribution of NOS3 rs1799983 and rs2070744 between GDM and healthy women. Moreover, among women treated with insulin, we observed an increased frequency of COX2 rs6681231 CC and NOS3 rs1799983 TT genotype carriers. CONCLUSIONS: The results of the present study suggest that the CC genotype of the COX2 rs6681231 polymorphism is associated with an increased risk of GDM and the need for insulin therapy, whereas the TT genotype of the NOS3 rs1799983 polymorphism may be associated with the need for insulin therapy in women with GDM.

Comparative in vitro study of single and four layer graphene oxide nanoflakes - Cytotoxicity and cellular uptake.

In recent years, graphene and its derivatives have been extensively investigated because of their unique properties, which can be used in many fields including biomedical applications. Therefore, detailed biological study is required. In the current paper the detailed toxicological studies on single and four layer graphene oxide (GO) nanoflakes is presented. The morphology and size of the nanomaterials were characterized via atomic force microscopy. Cytotoxicity, proliferation and internalization study were performed using various methods, including optical, confocal and Raman microscopy imaging, flow cytometry analysis, colorimetric and luminescent cell assays. Our first findings undeniably show that the nanomaterials' functionalization has a considerable impact on their behavior in a biological environment. The cytotoxicity assay confirmed comparable, dose dependent cytotoxicity of single and four layers GO flakes. The differences between these two nanomaterials became more distinct during cell proliferation study and ROS detection. Namely, markedly stronger inhibition of cell proliferation and higher ROS generation by one-layer GO-PEG than four-layer GO-PEG were observed. Cell imaging revealed efficient internalization of the both GO nanoflakes in a time dependent manner. These findings emphasize the role of number of layer and functionalization in GO toxicological characteristics and may provide helpful information for their further biomedical applications.

Effect of colorectal cancer on the number of normal stem cells circulating in peripheral blood.

Bone marrow (BM) residing stem cells are mobilized from their BM niches into peripheral blood (PB) in several pathological situations including tissue organ injury and systemic inflammation. We recently reported that the number of BM-derived stem cells (SCs) increases in patients with pancreatic and stomach cancer. Accordingly, we observed higher numbers of circulating very small embryonic/epiblast­like stem cells (VSELs) and mesenchymal stem cells (MSCs) that were associated with the activation of pro-mobilizing complement cascade and an elevated level of sphingosine-1 phosphate (S1P) in PB plasma. We wondered if a similar correlation occurs in patients with colorectal cancer (CRC). A total of 46 patients were enrolled in this study: 17 with CRC, 18 with benign colonic adenomas (BCA) and 11 healthy individuals. By employing fluorescence-activated cell sorting (FACS) we evaluated the number of BM-derived SCs circulating in PB: i) CD34+/Lin-/CD45- and CD133-/Lin-/CD45- VSELs; ii) CD45-/CD105+/CD90+/CD29+ MSCs; iii) CD45-/CD34+/CD133+/KDR+ endothelial progenitor cells (EPCs); and iv) CD133+/Lin-/CD45+ or CD34+/Lin-/CD45+ cells enriched for hematopoietic stem/progenitor cells (HSPCs). In parallel, we measured in the PB parameters regulating the egress of SCs from BM into PB. In contrast to pancreatic and gastric cancer patients, CRC subjects presented neither an increase in the number of circulating SCs nor the activation of pro-mobilizing factors such as complement, coagulation and fibrinolytic cascade, circulating stromal derived factor 1 (SDF­1), vascular endothelial growth factor (VEGF) and intestinal permeability marker (zonulin). In conclusion, mobilization of SCs in cancer patients depends on the type of malignancy and its ability to activate pro-mobilization cascades.