Effect of Axial Ligand Length on Biological and Anticancer Properties of Axially Disubstituted Silicon Phthalocyanines.

In this study, three new axially disubstituted silicon phthalocyanines (SiPc1-3) and their quaternized phthalocyanine derivatives (QSiPc1-3) were prepared and characterized. The biological properties (antioxidant, antimicrobial, antibiofilm, and microbial cell viability activities) of the water-soluble silicon phthalocyanines were examined, as well. A 1 % DMSO diluted with pure water was used as a solvent in biological activity studies. All the compounds exhibited high antioxidant activity. They displayed efficient antimicrobial and antimicrobial photodynamic therapeutic properties against various microorganisms, especially Gram (+) bacteria. Additionally, they demonstrated high antibiofilm activities against S. aureus and P. aeruginosa. In addition, 100 % bacterial reduction was obtained for all the studied phthalocyanines against E. coli viable cells. Besides, the DNA cleavage and binding features of compounds (QSiPc1-3) were studied using pBR322 DNA and CT-DNA, respectively. Furthermore, the human topoisomerase I enzyme inhibition activities of compounds QSiPc1-3 were studied. Anticancer properties of the water-soluble compounds were investigated using cell proliferation MTT assay. They exhibited anticarcinogenic activity against the human colon cancer cell line (DLD-1). Compounds QSiPc1 and QSiPc3 displayed a high anticarcinogenic effect on the DLD-1 cell line. The obtained results indicated that all the studied compounds may be effective biological agents and anticancer drugs after further investigations.

Bone marrow-derived mesenchymal stem cells alleviate paclitaxel-induced mechanical allodynia in rats.

Anticancer drug paclitaxel (PTX) frequently causes painful peripheral neuropathy; however, no medication has been shown to be effective in the treatment of this debilitating side effect. We aimed to investigate the efficacy of two different doses of allogeneic bone marrow-derived mesenchymal stem cells (BM-MSCs) on PTX-induced mechanical allodynia and spinal cytokine levels and their localization to target tissues such as the spinal cord and sciatic nerve. After the development of mechanical allodynia with repeated PTX administration, two different doses of rat BM-MSCs, low or high (1 × 106 -5 × 106 ), were transplanted into rats and the evaluation continued for 30 days. Interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and IL-10 levels in spinal cord samples of animals were analyzed by enzyme-linked immunosorbent assay. PTX-induced mechanical allodynia was relieved significantly 15 days after the transplantation of high-dose of BM-MSCs. Both MSCs doses were effective in alleviating allodynia, but the onset of effect was earlier with the high dose. High-dose of BM-MSCs significantly decreased spinal IL-1ß and TNF-α levels compared to the PTX group. Fluorescent dye-labeled BM-MSCs were observed much more frequently in the sciatic nerve and spinal cord samples of the high-dose BM-MSCs transplanted group than in the low-dose group animals. In conclusion, we found that the antiallodynic effects of BM-MSCs appeared earlier when high-dose of cells were administered. We think that other mechanisms may play a role in the effects of MSCs, besides localization to damaged tissues and reducing spinal inflammatory cytokine levels. We show that BM-MSCs can be a novel approach in PTX-induced mechanical allodynia.

Effects of combination TGF-B1 transfection and platelet rich plasma (PRP) on three-dimension chondrogenic differentiation of rabbit dental pulp-derived mesenchymal stem cells.

Aim: The aim of this study was to evaluate the effects of standard culture medium and chondrogenic differentiation medium with PRP on chondrogenic differentiation of rabbit dental pulp-derived mesenchymal stem cells (rabbit DPSCs) that are transfected with transforming growth factor-beta 1 (TGF-B1) gene, based on the hypothesis of TGF- B1 and PRP can be effective on the chondrogenesis of stem cells. Materials and Methods: Rabbit DPSCs were characterized by using flow cytometry, immunofluorescent staining, quantitative Real Time Polymerase Chain Reaction (qRT-PCR) and differentiation tests. For the characterization, CD29, CD44 and CD45 mesenchymal cell markers were used. Rabbit DPSCs were transfected with TGF-B1 gene using electroporation technique in group 1; with PRP 10% in group 2; with chondrogenic medium in group 3; with both chondrogenic medium and PRP in group 4. DPSCs were cultured in medium with 10% inactive PRP in group 5, chondrogenic medium in group 6, chondrogenic medium with PRP 10% in group 7. SOX9, MMP13 and Aggrecan gene expression levels were evaluated in 3, 6, 12. and 24. days by qRT-PCR. Results: The expression levels of SOX9, MMP13 and Aggrecan were higher in group 2, 3 and group 7 in 3th day however in 24th day group 7 and group 2 were found higher. The expression levels changed by time-dependent. The extracellular matrix of the cells in experimental groups were positively stained with safranin O and toluidine blue. Conclusion: The combination in culture medium of TGF-B1 gene transfection and 10% PRP accelerates the chondrogenic differentiation of DPSCs.

Prevention of Burn Wound Progression by Mesenchymal Stem Cell Transplantation: Deeper Insights Into Underlying Mechanisms.

INTRODUCTION: Burns are dynamic wounds that may present a progressive expansion of necrosis into the initially viable zone of stasis. Therefore, salvage of this zone is a major subject of focus in burn research. The beneficial effects of mesenchymal stem cells (MSCs) on the survival of the zone of stasis have been previously documented. However, many gaps still exist in our knowledge regarding the underlying protective mechanisms. Hence, this study was designed to evaluate the pathophysiological basis of MSCs in the prevention of burn wound progression. METHODS: Wistar rats received thermal trauma on the back according to the "comb burn" model. Animals were randomly divided into sham, control, and stem cell groups with sacrifice and analysis at 72 hours after the burn. The stasis zones were evaluated using histochemistry, immunohistochemistry, biochemistry, real-time polymerase chain reaction assay, and scintigraphy to evaluate the underlying mechanisms. RESULTS: Gross evaluation of burn wounds revealed that vital tissue percentage of the zone of stasis was significantly higher in the stem cell group. Semiquantitative grading of the histopathologic findings showed that MSCs alleviated burn-induced histomorphological alterations in the zone of stasis. According to CC3a staining and expression analysis of Bax (B-cell leukemia 2-associated X) and Bcl-2 (B-cell leukemia 2) genes, MSCs attenuated increases in apoptosis postburn. In addition, these transplants showed an immunomodulatory effect that involves reduced neutrophilic infiltration, down-regulation of proinflammatory cytokines (tumor necrosis factor α, interleukin 1ß [IL-1ß], and IL-6), and up-regulation of the anti-inflammatory cytokine IL-10 in the zone of stasis. Burn-induced oxidative stress was significantly relieved with MSCs, as shown by increased levels of malondialdehyde, whereas the expression and activity of the antioxidant enzyme superoxide dismutase were increased. Finally, MSC-treated interspaces had enhanced vascular density with higher expression levels for vascular endothelial growth factor A, platelet-derived growth factor, fibroblast growth factor, and transforming growth factor ß. Gamma camera images documented better tissue perfusion in animals treated with MSCs. CONCLUSIONS: The protective effects of MSCs are mediated by the inhibition of apoptosis through immunomodulatory, antioxidative, and angiogenic actions.

Pituitary Cell Turnover: From Adult Stem Cell Recruitment through Differentiation to Death.

The recent demonstration using genetic tracing that in the adult pituitary stem cells are normally recruited from the niche in the marginal zone and differentiate into secretory cells in the adenopituitary has elegantly confirmed the proposal made when the pituitary stem cell niche was first discovered 5 years ago. Some of the early controversies have also been resolved. However, many questions remain, such as which are the markers that make a pituitary stem cell truly unique and the exact mechanisms that trigger recruitment from the niche. Little is known about the processes of commitment and differentiation once a stem cell has left the niche. Moreover, the acceptance that pituitary cells are renewed by stem cells implies the existence of regulated mechanisms of cell death in differentiated cells which must themselves be explained. The demonstration of an apoptotic pathway mediated by RET/caspase 3/Pit-1/Arf/p53 in normal somatotrophs is therefore an important step towards understanding how pituitary cell number is regulated. Further work will elucidate how the rates of the three processes of cell renewal, differentiation and apoptosis are balanced in tissue homeostasis after birth, but altered in pituitary hyperplasia in response to physiological stimuli such as puberty and lactation. Thus, we can aim to understand the mechanisms underlying human disease due to insufficient (hypopituitarism) or excess (pituitary tumor) cell numbers.

Assessment of Genomic and Metabolic Characteristics of Cholesterol-Reducing and GABA Producer Limosilactobacillus fermentum AGA52 Isolated from Lactic Acid Fermented Shalgam Based on "In Silico" and "In Vitro" Approaches.

This study aimed to characterize the genomic and metabolic properties of a novel Lb. fermentum strain AGA52 which was isolated from a lactic acid fermented beverage called "shalgam." The genome size of AGA52 was 2,001,184 bp, which is predicted to carry 2024 genes, including 50 tRNAs, 3 rRNAs, 3 ncRNAs, 15 CRISPR repeats, 14 CRISPR spacers, and 1 CRISPR array. The genome has a GC content of 51.82% including 95 predicted pseudogenes, 56 complete or partial transposases, and 2 intact prophages. The similarity of the clusters of orthologous groups (COG) was analyzed by comparison with the other Lb. fermentum strains. The detected resistome on the genome of AGA52 was found to be intrinsic originated. Besides, it has been determined that AGA52 has an obligate heterofermentative carbohydrate metabolism due to the absence of the 1-phosphofructokinase (pfK) enzyme. Furthermore, the strain is found to have a better antioxidant capacity and to be tolerant to gastrointestinal simulated conditions. It was also observed that the AGA52 has antimicrobial activity against Yersinia enterocolitica ATCC9610, Bacillus cereus ATCC33019, Salmonella enterica sv. Typhimurium, Escherichia coli O157:h7 ATCC43897, Listeria monocytogenes ATCC7644, Klebsiella pneumoniae ATCC13883, and Proteus vulgaris ATCC8427. Additionally, AGA52 exhibited 42.74 ± 4.82% adherence to HT29 cells. Cholesterol assimilation (33.9 ± 0.005%) and GABA production capacities were also confirmed by "in silico" and "in vitro." Overall, the investigation of genomic and metabolic features of the AGA52 revealed that is a potential psychobiotic and probiotic dietary supplement candidate and can bring functional benefits to the host.

Dental Pulp-Derived Mesenchymal Stem Cells Increase Axon Numbers in Mental Nerve Repair.

Aim: The mental nerve, the extended part of the inferior alveolar nerve, is often injured during dentoalveolar, orthognathic, or tumor surgery. Numerous therapeutic interventions, including surgery and pharmacotherapy, have been used to enhance the recovery of nerve injuries. Dental pulp stem cells (DPSCs) represent an easily accessible source of adult stem cells that can be isolated from the pulp of extracted teeth. This study evaluated the effect of DPSCs on the regeneration of the mental nerve injury model of rabbits. Methods: In this presented study, DPSCs were cultured and cell characterizations were performed by using flow cytometry and immunostainings. Bilateral mental nerve injury models of rabbits were created. In the control group (n = 10), saline was applied, and in the study group (n = 10), 2 × 106 DPSCs were applied to the repaired nerve areas. After 3 weeks, animals were killed and histological examination was obtained by using Masson's trichrome staining. An unpaired Student's t test was used when comparing the groups. Differences were considered to be statistically significant at P values of less than 0.05. Results: The DPSCs demonstrated a homogeneous population of mesenchymal stromal cells which expressed cluster of differentiation CD44, CD73, CD90, and CD105 and lack of CD34, CD45, and HLA-DR. Our finding clearly demonstrated that a lower number of cross-sectioned axons were founded in the control group (60.18 ± 2.52) compared to the study group (72.96 ± 2.43) (p = 0.00). Conclusions: DPSCs promote mental nerve axonal regeneration. These results suggest that DPSCs provide an important accessible source of adult stem cells for mental nerve regeneration.

Design of N-heterocycle based-phthalonitrile/metal phthalocyanine-silver nanoconjugates for cancer therapies.

This study reports the anticancer properties of carbazole-containing phthalonitrile/phthalocyanine-modified silver nanoparticles for the first time. In this study, a new mono-substituted phthalonitrile namely 3-[9H-carbazole-9-ethoxy]phthalonitrile and its metal phthalocyanines {M = Zn, Co, and Mn(Cl)} were synthesized by template cyclotetramerization of phthalonitrile derivatives. The newly synthesized compounds were characterized using UV-vis, FT-IR, 1H NMR, 13C NMR, and mass spectroscopy. The resultant compounds were successfully linked to the surface of silver nanoparticles. The characterization of the surficial modification was carried out by applying the TEM technique. The cytotoxic activities of the studied nanoconjugates were tested against A549, DLD-1, and Wi38 cell lines by performing a (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay with/without irradiation. Although the functionalization of silver nanoparticles increased the solubility of phthalocyanines in aqueous media, the presence of phthalonitrile/phthalocyanine derivatives on the silver nanoparticles' surface improved their biological properties. All the studied biological candidates exhibited antiproliferative activities against the cell lines. The IC50 values calculated were between 6.80 and 97.99 µM against the studied cell lines in the dark. However, the IC50 values determined were between 3.11 and 88.90 µM with irradiation. The highest IC50 values obtained were 3.11 and 3.52 µM against the DLD-1 cell line for nanoconjugates 1-AgNP and 3-AgNP, respectively. The findings indicated that the compounds may be utilized as anticancer agents after further studies.

The effect of phthalocyanine's periphery on the biological activities of carbazole-containing metal phthalocyanines.

This study reports the synthesis and characterization of two new mono- and di-substituted phthalonitriles namely 4-((9H-carbazol-3-yl)oxy)-5-chlorophthalonitrile and 4,5-bis((9H-carbazol-3-yl)oxy)phthalonitrile, respectively. Cyclotetramerization of the new phthalonitriles in the presence of zinc(II) acetate resulted in related zinc(II) phthalocyanines. To study the effect of the position and number of substituents on the biological properties of the phthalocyanines, peripherally or non-peripherally tetra-substituted zinc(II) phthalocyanines bearing (9H-carbazol-3-yl)oxy groups, as well as axially di-substituted silicon phthalocyanines containing the same groups, were prepared. Since gold nanoparticles are well-known as efficient drug delivery agents, the surface of these metal nanoparticles was functionalized with all the compounds. This modification also improved the solubility of the phthalocyanines in aqueous media. In this study, the antioxidant, DNA cleavage, and toxic/phototoxic activities of the resultant nanoconjugates were examined. With a combination of metal ion and substituent (nature, number, and position) effects, the silicon(IV) phthalocyanine exhibited the highest biological properties.

Anticancer and biological properties of new axially disubstituted silicon phthalocyanines.

This study reports the synthesis of three novel axially disubstituted silicon phthalocyanines (1-3-Si) and their quaternized phthalocyanines (1-3-QSi). The resulting compounds were characterized by applying spectroscopic techniques including 1H NMR, FT-IR, UV-vis, and mass spectroscopy. The biological properties of compounds 1-3-QSi, including DNA cleavage activities, DNA binding modes, and topoisomerase enzyme inhibition activities, were investigated using agarose gel electrophoresis. pBR322 plasmid DNA, CT-DNA, and AL-DNA (isolated from apricot leaf) were used for DNA studies. All the quaternized compounds exhibited acceptable DNA cleavage activities. Human topoisomerase I and E. coli topoisomerase enzymes were used for the topoisomerase I inhibition studies. All the quaternized complexes inhibited topoisomerase I activity. Moreover, these compounds were screened for cytotoxic and apoptotic effects against a human colon cancer cell line (DLD-1) by performing MTT and Annexin V assays. They exhibited toxicity and apoptotic effect on the DLD-1 cell line. The findings reveal that the compounds can be utilized for cancer therapy after further investigations.

Repair of Rat Calvarial Bone Defect by Using Exosomes of Umbilical Cord-Derived Mesenchymal Stromal Cells Embedded in Chitosan/Hydroxyapatite Scaffolds.

PURPOSE: To seek out the bone regeneration effect of human umbilical cord-mesenchymal stem cell (hUC-MSC)-derived exosomes of loaded chitosan/hydroxyapatite (CS/HA) scaffold in a rat calvarium bone regeneration model. MATERIALS AND METHODS: The hUC-MSC exosomes were purified and characterized. The scaffolds were prepared by a freeze-drying method. Animals were divided into five groups, and the CS/HA/exosome (CS/HA/Exo) scaffolds were transplanted to 5 × 2-mm critical-sized calvarial bone defects for repair in rats. All animals were sacrificed at the postoperative sixth week. Immunohistochemical and histologic analyses were performed. RESULTS: Scanning electron microscopy (SEM) images showed that the exosomes were round-shaped vesicles with bounded membrane, and the diameter of the exosomes was 83.728 ± 27.269 nm. Histologic analysis showed that mean new bone volumes were statistically significantly higher in the CS/HA/Exo group (1.83 ± 0.54, PCS/Exo-CS/HA/Exo = .000), and other new bone volumes in the other groups were statistically significant compared with the control (CS/Exo 1.50 ± 0.14 mm3; CS 1.20 ± 0.43 mm3; control 1.06 ± 0.10 mm3; and CS/HA 1.43 ± 0.66 mm3). CONCLUSION: The CS/HA/Exo combination is a novel treatment for bone defect repair to induce bone formation. The CS scaffold can significantly promote bone regeneration compared with the control. Moreover, the combination with HA and exosomes is promising for applications in bone tissue regeneration.

Effects of TGF-ß1 Overexpression on Biological Characteristics of Human Dental Pulp-derived Mesenchymal Stromal Cells.

OBJECTIVE: The aim of our study was to investigate the effect of Transforming growth factor beta-1 (TGF-ß1) gene therapy on the surface markers, multilineage differentiation, viability, apoptosis, cell cycle, DNA damage and senescence of human Dental Pulp-derived Mesenchymal Stromal Cells (hDPSC). METHODS: hDPSCs were isolated from human teeth, and were cultured with 20% Fetal Bovine Serum (FBS) in minimum essential media-alpha (α-MEM). TGF-ß1 gene transfer into hDPSCs was performed by electroporation method after the plasmid was prepared. The transfection efficiency was achieved by using western blot and flow cytometry analyses and GFP transfection. Mesenchymal stem cell (MSC) markers, multilineage differentiation, cell proliferation, apoptosis, cell cycle, DNA damage and cellular senescence assays were performed by comparing the transfected and non-transfected cells. Statistical analyses were performed using GraphPad Prism. RESULTS: Strong expression of TGF-ß1 in pCMV-TGF-ß1-transfected hDPSCs was detected in flow cytometry analysis. TGF-ß1 transfection efficiency was measured as 95%. Western blot analysis showed that TGF-ß1 protein levels increased at third and sixth days in pCMV-TGF-ß1-transfected hDPSCs. The continuous TGF-ß1 overexpression in hDPSCs did not influence the immunophenotype and surface marker expression of MSCs. Our results showed that TGF-ß1 increased osteogenic and chondrogenic differentiation, but decreased adipogenic differentiation. Overexpression of TGF-ß1 increased the proliferation rate and decreased total apoptosis in hDPSCs (p<0.05). The number of cells at “S” phase was higher with TGF-ß1 transfection (p＜0.05). Cellular senescence decreased in TGF-ß1 transfected group (p＜0.05). CONCLUSIONS: These results reflect that TGF-ß1 has major impact on MSC differentiation. TGF-ß1 transfection has positive effect on proliferation, cell cycle, and prevents cellular senescence and apoptosis.

Bone Marrow Mesenchymal Stem Cell Transplantation Enhances Nerve Regeneration in a Rat Model of Hindlimb Replantation.

BACKGROUND: Successful limb replantation must be based not only on the viability of the amputated part but also on satisfactory long-term functional recovery. Once the vascular, skeletal, and soft-tissue problems have been taken care of, nerve recovery becomes the ultimate limiting factor. Unfortunately, nerve regeneration after limb replantation is impaired by several consequences. The authors tested the hypothesis that bone marrow mesenchymal stem cells could improve nerve regeneration outcomes in an experimental model of limb replantation. METHODS: Twenty rats underwent replantation after total hindlimb amputation. Animals were subdivided into two groups: a replanted but nontreated control group and a replanted and bone marrow mesenchymal stem cell-transplanted group. Three months after surgery, nerve regeneration was assessed using functional, electrophysiologic, histomorphologic, and immunohistochemical analyses. RESULTS: Bone marrow mesenchymal stem cell-treated animals showed significantly better sciatic functional index levels and higher compound muscle action potential amplitudes in comparison with the controls. Histomorphometric analysis revealed that the number of regenerating axons was approximately two-fold greater in the treated nerves. In addition, the mean g-ratio of these axons was within the optimal range. Immunohistochemical assessment revealed that expression of S-100 and myelin basic protein in the treated nerves was significantly higher than in controls. Correspondingly, the expression levels of anti-protein gene product 9.5 and vesicular acetylcholine transporter in motor endplates were also significantly higher. Finally, muscles in the bone marrow mesenchymal stem cell-transplanted group showed significantly larger average fiber areas. CONCLUSION: The authors' findings demonstrate that it is possible to improve the degree of nerve regeneration after limb replantation by bone marrow mesenchymal stem cell transplantation.

The Effects of Anti-Vascular Endothelial Growth Factor Drugs on Retinal Pigment Epithelial Cell Culture.

OBJECTIVES: To assess the effects of anti-vascular endothelial growth factor (VEGF) drugs on retinal pigment epithelium cell culture. MATERIALS AND METHODS: Aflibercept (0.5 mg/mL), bevacizumab (0.3125 mg/mL), and ranibizumab (0.125 mg/mL) were applied to retinal pigment epithelium cell cultures isolated from the enucleated eyes of New Zealand white rabbits. Viability, apoptosis, proliferation, and senescence of the cells were evaluated in control and drug-treated cultures at the end of 72 hours. RESULTS: Cells treated with aflibercept showed increased viability and decreased apoptosis compared to the control culture and both the bevacizumab- and ranibizumab-treated groups (p<0.05). Statistically increased apoptosis and decreased viability were found in the bevacizumab and ranibizumab-treated groups compared with the control group (p<0.05). There were no statistically significant differences in cell proliferation and senescence between the groups (p>0.05). CONCLUSION: Anti-VEGF drugs did not affect senescence or proliferation of retinal pigment epithelium cells. Aflibercept was found to decrease apoptosis and increase cell viability, while ranibizumab and bevacizumab increased apoptosis and reduced cell viability in retinal pigment epithelium culture.