Vitamin D3 Stimulates Proliferation Capacity, Expression of Pluripotency Markers, and Osteogenesis of Human Bone Marrow Mesenchymal Stromal/Stem Cells, Partly through SIRT1 Signaling

The biology of vitamin D3 is well defined, as are the effects of its active metabolites on various cells, including mesenchymal stromal/stem cells (MSCs). However, the biological potential of its precursor, cholecalciferol (VD3), has not been sufficiently investigated, although its significance in regenerative medicine—mainly in combination with various biomaterial matrices—has been recognized. Given that VD3 preconditioning might also contribute to the improvement of cellular regenerative potential, the aim of this study was to investigate its effects on bone marrow (BM) MSC functions and the signaling pathways involved. For that purpose, the influence of VD3 on BM-MSCs obtained from young human donors was determined via MTT test, flow cytometric analysis, immunocytochemistry, and qRT-PCR. Our results revealed that VD3, following a 5-day treatment, stimulated proliferation, expression of pluripotency markers (NANOG, SOX2, and Oct4), and osteogenic differentiation potential in BM-MSCs, while it reduced their senescence. Moreover, increased sirtuin 1 (SIRT1) expression was detected upon treatment with VD3, which mediated VD3-promoted osteogenesis and, partially, the stemness features through NANOG and SOX2 upregulation. In contrast, the effects of VD3 on proliferation, Oct4 expression, and senescence were SIRT1-independent. Altogether, these data indicate that VD3 has strong potential to modulate BM-MSCs’ features, partially through SIRT1 signaling, although the precise mechanisms merit further investigation

Association between oxidative stress and melanoma progression

Background: Overproduction of free radicals accompanied with their insufficient removal/neutralization by antioxidative defense system impairs redox hemostasis in living organisms. Oxidative stress has been shown to be involved in all the stages of carcinogenesis and malignant melanocyte transformation. The aim of this study was to examine association between oxidative stress development and different stages of melanoma. Methods: The measured oxidative stress parameters included: superoxide anion radical, total and manganese superoxide dismutase, catalase and malondialdehyde. Oxidative stress parameters were measured spectrophotometrically in serum samples from melanoma patients (n=72) and healthy control subjects (n=30). Patients were classified according to AJCC clinical stage. Results: Average superoxide anion and malondialdehyde concentrations were significantly higher in melanoma patients than in control group, with the highest value of superoxide anion in stage III, while malondialdehyde highest value was in stage IV. The activity of total and manganese superoxide dismutase was insignificantly higher in melanoma patients than in control group, while catalase activity was significantly higher. The highest activity of total superoxide dismutase was in stage III, while the highest activity of manganese superoxide dismutase was in stage IV. Catalase activity was increasing with the disease progression achieving the maximum in stage III. Conclusions: Results of our study suggest that melanoma is oxidative stress associated disease, as well as deteriorated cell functioning at mitochondrial level

The Simple Isocratic HPLC-UV Method for the Simultaneous Determination of Reduced and Oxidized Glutathione in Animal Tissue

The aim of our work was to optimize and apply simple high-performance liquid chromatography method with ultraviolet detection (HPLC-UV) for simultaneous determination of reduced (GSH) and oxidized (GSSG) glutathione in biological matrix (specifically, the rat liver tissue was used herein), since the ratio between oxidized and reduced glutathione forms (GSSG-GSH) has been recognized as an important biological marker of oxidatively depleted GSH in oxidative stress (OS)-associated diseases and poisonings. An isocratic chromatographic separation of GSH and GSSG (2.8 min and 6.3 min, respectively) was performed with the mobile phase consisted of sodium perchlorate solution (pH adjusted to 2.8) at flow rate of 1 mL min(-1), detection set at 215 nm, and column temperature of 40 degrees C. The method offers short run time, linearity in the range of 0.01-200 mu M concentration for both compounds (R-2 = 1), low limits of detection and quantification (GSH: 0.18 mu M and 0.56 mu M, GSSG: 0.52 mu M and 1.58 mu M, respectively), precision, accuracy (bias lt 2%), and high reproducibility. Through suitable sample handling, an overestimation of GSSG was prevented. High recovery (>99%) was achieved. The method was successfully applied for the analysis of GSH and GSSG in liver homogenates of Wistar rats intraperitoneally exposed to cadmium (Cd) (1 mg kg(-1) CdCl2/21 days). Regardless of other Cd-mediated hepatotoxicity mechanisms, herein, we have exclusively interpreted/emphasized oxidative GSH depletion. The presented method is acceptable for a routine analysis of GSH and GSSG in biological matrix, while the calculated ratio GSSG-GSH is considered as a valuable OS marker

Zeolite pretreatment accomplishes partial brain radioprotective role by reducing iron and oxidative / nitrosative stress in rats

The aim of our study was to test the effect of subacutely applied micronized zeolite [micronized clinoptilolite (MZC)] on brain status of iron (Fe), reactive oxygen and nitrogen species (ROS, RNS), and radioprotective role against brain oxidative/nitrosative stress (OS/NS) initiated by single ionizing radiation of 2 or 10Gray (Gy). Wistar rats on normal (n=18) and 5% MZC supplemented diet (n=18), during 4 weeks, were internally subdivided into 3 subgroups (6 rats in each subgroup), with one of subgroup remaining as a control, and the other two subjected to single ionizing radiation of 2Gy or 10Gy. Thus, we had groups on normal diet: C – controls, 2Gy and 10Gy; and on 5% MZC supplemented diet: MZC, MZC+2Gy and MZC+10Gy. Concentrations of nitrates (a final RNS metabolite) and superoxide anion radical (O2 •-) (an initial ROS) were measured in homogenates of selective vulnerable brain regions (cerebellum, hippocampus and forebrain cortex), while Fe was determined in whole brain of rats. Results documented a significant drop of Fe in MZC and MZC+2Gy/10Gy groups; decrease of O2 •- and nitrate in MZC group; almost equal drop of O2 •- , in 2Gy and MZC+2Gy groups; and nitrate increase in 10Gy and MZC+10Gy groups. We confirmed that subacute MZC pretreatment contributes to partially accomplished brain radioprotective effect in rats exposed to single radiation dose of 2Gy and 10Gy, probably due to reduced OS/NS and Fe

Subacute alcohol and/or disulfiram intake affects bioelements and redox status in rat testes

The aim of the study was to investigate if alcohol and disulfiram (DSF) individually and in combination affect bioelements' and red-ox homeostasis in testes of the exposed rats. The animals were divided into groups according to the duration of treatments (21 and/or 42 days): C-21/C-42 groups (controls); OL21 and OL22-42 groups (0.5 mL olive oil intake); A(1-21) groups (3 mL 20% ethanol intake); DSF1-21 groups (178.5 mg DSF/kg/day intake); and A(21)+DSF22-42 groups (the DSF ingestion followed previous 21 days' treatment with alcohol). The measured parameters in testes included metals: zinc (Zn), copper (Cu), iron (Fe), magnesium (Mg) and selenium (Se); as well as oxidative stress (OS) parameters: superoxide anion radical (O-2(center dot-)), glutathione reduced (GSH) and oxidized (GSSG), malondialdehyde (MDA), hydrogen peroxide (H2O2) decomposition and activities of total superoxide dismutase (tSOD), glutathione-Stransferase (GST) and glutathione reductase (GR). Metal status was changed in all experimental groups (Fe rose, Zn fell, while Cu increased in A(21)+DSF24-32 groups). Development of OS was demonstrated in A(1-21) groups, but not in DSF1-21 groups. In A(21)+DSF22-42 groups, OS was partially reduced compared to A groups (A(1-21)>MDA>C; A(1-21) lt GSH lt C). High metal-binding affinity of DSF/DDTC changes red-ox homeostasis in rat testes

In vitro antioxidant activity of thiazolidinone derivatives of 1,3-thiazole and 1,3,4-thiadiazole

The initial steps in preclinical drug developing research concern the synthesis of new compounds for specific therapeutic use which needs to be confirmed by in vitro and then in vivo testing. Nine thiazolidinone derivatives (numerically labeled 1-9) classified as follows: 1,3-thiazole-based compounds (1 and 2); 1,3,4-thiadiazole based compounds (3 and 4); substituted 5-benzylideno-2-adamantylthiazol[3,2-b] [1,2,4] triazol-6(5H) ones (5-8); and an ethylaminothiazole-based chalcone (9), were tested for antioxidant activity (AOA) by using three in vitro assays: DPPH (1,1-diphenyl-2-picrylhydrazyl scavenging capacity test); FRAP (ferric reducing antioxidant power test); and TBARS (thiobarbituric acid reactive substances test). Compounds 1-4 and 9 in particular are newly synthesized compounds. Also, traditional antioxidants Vitamins E and C and alpha-lipoic acid (alpha-LA) were tested. The results of DPPH testing: Vitamin C 94.35%, Vitamin E 2.99% and alpha-LA 1.57%; compounds: 4 33.98%; 2 18.73%; 1 15.62%; 5 6.59%; 3 4.99%; 6-9 demonstrated almost no AOA. The results of TBARS testing (% of LPO inhibition): Vitamin C 62.32%; Vitamin E 36.29%; alpha-LA 51.36%; compounds: 1 62.11%; 5 66.71%; 9 60.93%; 4, 6 and 7 demonstrated similar to 50%; 3 and 8 displayed similar to 38%; 2 23.51%. By FRAP method, Vitamins E and C showed equal AOA, similar to 100%, unlike alpha-LA (no AOA), and AOA of the tested compounds (expressed as a fraction of the AOA of Vitamin C) were: 2 and 4-75%; 8, 3 and 1-45%; 5-7 and 9-27%. Different red-ox reaction principles between these assays dictate different AOA outcomes for a single compound. Vitamin C appeared to be the superior antioxidant out of the traditional antioxidants; and compound 4 was superior to other tested thiazolidinone derivatives. Vitamin C appeared to be the superior antioxidant out of the traditional antioxidants; and compound 4 was superior to other tested thiazolidinone derivatives. Phenyl-functionalized benzylidene, amino-carbonyl functional domains and chelating ligand properties of the thiazolidinone derivatives correlated with AOA

Oxidative stress, bioelements and androgen status in testes of rats subacutely exposed to cadmium

The objective of our study was to examine testicular toxicity of cadmium (Cd), focusing on oxidative stress (OS), essential metals and androgenic status and morphological changes. Male Wistar rats [controls and four Cd-subgroups (n = 6) organized according to the exposure (1, 3, 10 and 21 days)] were intraperitoneally (i.p.) treated with 1 mg CdCl2/kg/day. Testicular Cd deposition was noticed from the 1st day. After 10 and 21 days, copper (Cu) and iron (Fe) increased by 60-109% and 43-67%, respectively, while zinc (Zn) decreased by 24-33%. During 121 days of the exposure, decrease in testicular total superoxide dismutase (SOD) and total glutathione-s-transferase (GST) activities occurred gradually by 30-78% and 15-84%, respectively, while superoxide anion radical (O-2(center dot-)) increased gradually by 114-271%. After 10-21 days, decrease in testicular catalase (CAT) activity appeared by 13-31%. After 21 days, malondialdehyde (MDA) decreased by 44% and the ratio of oxidized glutathione/reduced glutathione (GSSG/GSH) increased by 130% in testes of the rats exposed to Cd. Additionally, decreased testicular testosterone level and the relative testes mass, along with induced microscopic and macroscopic changes were occured, what can be explained as the consequence of instantly developed OS, impaired essential metals status and Cd testicular deposition