High Dose Pomegranate Extract Suppresses Neutrophil Myeloperoxidase and Induces Oxidative Stress in a Rat Model of Sepsis.

Introduction: The effect of using high dose pomegranate extract on sepsis and its safety is not clarified. Considering the fact that proper immune and inflammatory responses are needed to cope with infection, the aim of current study was to assess the effect of high dose pomegranate extract consumption on oxidative and inflammatory responses after disease induction in rat model of sepsis. METHODS: Sepsis was induced by Cecal Ligation and Perforation (CLP) surgery. Adult male Wistar rats were divided into three groups of eight animals: Sham; CLP and POMx [consumed POMx (250 mg of pomegranate fruit extract/kg/day) for four weeks before CLP]. RESULTS: Peritoneal neutrophil myeloperoxidase activity was significantly lower in POMx compared with Sham and CLP groups (p < 0.01 and p < 0.05, respectively). Although antioxidant enzymes were higher in POMx group after sepsis induction, lower serum total antioxidant status (TAS) (p < 0.01 compared with both CLP and Sham groups) and higher liver thiobarbituric acid reactive species (TBARS) levels were observed in this group (p < 0.01 and p < 0.05, compared with Sham and CLP groups, respectively). CONCLUSION: High dose POMx consumption prior to sepsis induction, suppressed the vital function of neutrophils in early hours after sepsis initiation, resulting in higher oxidative stress. These findings indicate that caution should be made in using high dose pomegranate products. The main message of current study is that such useful compounds as antioxidants including pomegranate juice which have beneficial effects on general health status may have detrimental effects if misused or used in high doses.

Mouse preantral follicle growth in 3D co-culture system using human menstrual blood mesenchymal stem cell.

Follicle culture provides a condition which can help investigators to evaluate various aspects of ovarian follicle growth and development and impact of different components and supplementations as well as presumably application of follicle culture approach in fertility preservation procedures. Mesenchymal Stem Cells (MSCs), particularly those isolated from menstrual blood has the potential to be used as a tool for improvement of fertility. In the current study, a 3D co-culture system with mice preantral follicles and human Menstrual Blood Mesenchymal Stem Cells (MenSCs) using either collagen or alginate beads was designed to investigate whether this system allows better preantral follicles growth and development. Results showed that MenSCs increase the indices of follicular growth including survival rate, diameter, and antrum formation as well as the rate of in vitro maturation (IVM) in both collagen and alginates beads. Although statistically not significant, alginate was found to be superior in terms of supporting survival rate and antrum formation. Hormone assay demonstrated that the amount of secreted 17 ß-estradiol and progesterone in both 3D systems increased dramatically after 12 days, with the highest levels in system employing MenSCs. Data also demonstrated that relative expression of studied genes increased for Bmp15 and Gdf9 and decreased for Mater when follicles were cultured in the presence of MenSCs. Collectively, results of the present study showed that MenSCs could improve indices of follicular growth and maturation in vitro. Further studies are needed before a clinical application of MenSCs-induced IVM is considered.

Facile fabrication of nickel immobilized on magnetic nanoparticles as an efficient affinity adsorbent for purification of his-tagged protein.

In the present research, an efficient, convenient, and inexpensive method for the one-pot synthesis of Fe3O4@Histidine is developed. Histidine is readily loaded on magnetic nanoparticles by one step and simple method without any supplemental linkers. In the structure of Fe3O4@Histidine, histidine covalently immobilized on the surface of Fe3O4, magnetic nanoparticles are able to trap Ni2+ ions through a strong interaction between nickel and histidines in protein tag. Two coordination sites of nickel are occupied with ligand on the surface of magnetic nanoparticles and four coordination sites have been remained that these sites will be occupied with histidine tag of recombinant protein A. The functionalized nanoparticles were spherical and well separated with an average diameter around 30nm. The obtained magnetic nanoparticles have a saturation magnetization of about 54emu/g. Fe3O4@Histidine-Ni was used to enrich and purify 6×histidine-tagged recombinant protein-A directly from the mixture of lysed cells. It has been found that Ni(II)-immobilized Fe3O4@Histidine magnetic nanoparticles present negligible nonspecific protein adsorption and high His-tag protein binding capacity The average binding capacity (MW 42k Da), is 700±25µg·mg-1 (protein/Fe3O4@Histidine-Ni).

Vitamin A Decreases Cytotoxicity of Oxidized Low-Density Lipoprotein in Patients with Atherosclerosis.

BACKGROUND: Oxidized low-density lipoprotein (ox-LDL) is implicated in initiation and progression of atherosclerosis. Previously, we found that ox-LDL increases vulnerability of peripheral blood mononuclear cells (PBMCs) in atherosclerotic patients compared to controls. Vitamin A induces proliferation of PBMCs. The aim of this study was to determine the effect of vitamin A supplementation on PBMC survival against LDL and different doses of ox-LDL. METHOD: In this double-blind placebo-controlled trial, we recruited 35 atherosclerotic patients and 38 healthy controls and randomly allocated them into placebo and vitamin A groups, which received either placebo or 25,000 IU/day of vitamin A for 3 months. PBMCs were isolated, cultured, and stimulated by 1 µg/mL LDL as well as 1 µg/mL and 50 µg/mL ox-LDL. The stimulation indexes (SIs) of PBMCs were calculated to identify cell viability. Additionally, the circulating ox-LDL levels were measured by ELISA. RESULTS: Viability of PBMCs stimulated by 50 µg/mL ox-LDL significantly increased following vitamin A supplementation in patients (p < 0.01). The levels of circulating ox-LDL were not changed by vitamin A treatment. Ox-LDL levels were strongly and positively correlated to SI of PBMCs stimulated by 1 µg/mL LDL and1 µg/mL ox-LDL in all groups. CONCLUSION: Vitamin A decreases cytotoxicity of high-dose ox-LDL and improves PBMC viability. The protective effect of vitamin A is not mediated by an antioxidative mechanism, but may instead have been due to intracellular protection of the apoptotic machinery or induction of proliferation of the cells. Higher levels of ox-LDL increase PBMC irritability in all participants.

Comparative effect of human platelet derivatives on proliferation and osteogenic differentiation of menstrual blood-derived stem cells.

Menstrual blood has been recognized as an easily accessible and inexpensive source of stem cells, in recent years. To establish a safe and efficient protocol for development of menstrual blood-derived stem cells (MenSCs) into osteoblasts, the effect of substitution of fetal bovine serum (FBS) with human platelet derivatives (HPDs) was evaluated during proliferation and osteogenic differentiation of MenSCs. To this aim, parallel experiments were carried out on cultured MenSCs in the presence of platelet-rich plasma, platelet-poor plasma, platelet gel supernatant, or human platelet releasate (HPR), and compared with cells cultured in conventional growth medium containing FBS. There was no significant difference between growth curves of cultured MenSCs in presence of different fortified media. However, the MenSCs demonstrated variant differentiation patterns in response to FBS replacement with HPDs. Mineralization, as judged by Alizarin red staining, was significantly higher in cells differentiated in the presence of HPR compared to cells that were fortified with other medium supplements. A greater osteocalcin production level, alkaline phosphatase activity, and mRNA expression of osteogenic-specific genes in differentiated MenSCs under HPR condition further confirmed our previous findings. Based on our data, FBS substitution by HPDs not only allows for successful MenSCs proliferation, but also promotes MenSCs development into osteoblasts. The effectiveness of HPR on osteogenic differentiation of MenSCs represents an important novel step toward safe and applied stem cell therapy of bone diseases.

Osteogenic differentiation of stem cells derived from menstrual blood versus bone marrow in the presence of human platelet releasate.

In recent decades, stem cell therapy has been introduced as a novel therapeutic approach for patients suffering from bone disorders. Recently, menstrual blood has been identified as an easily accessible and recycled stem cell source. However, the osteogenic differentiation capacity of menstrual blood-derived stem cells (MenSCs) compared with other adult stem cells remained unsolved. The aim of this study was to investigate the osteogenic differentiation capacity of MenSCs compared to bone marrow-derived mesenchymal stem cells (BMSCs) in the presence of human platelet releasate (HPR). Our results showed that MenSCs were strongly positive for mesenchymal and negative for hematopoietic stem cell markers in a similar manner to BMSCs. In contrary to BMSCs, MenSCs exhibited marked expression of OCT-4 and a significantly higher proliferative capacity. Mineralization, as judged by alizarin red staining, was more pronounced in differentiated BMSCs than in differentiated MenSCs in an osteogenic medium fortified with fetal bovine serum (FBS). However, FBS substitution with HPR in a differentiation medium resulted in typical impact on intensity of MenSC mineralization. The results of semiquantitative reverse transcription-polymerase chain reaction showed comparable levels of parathyroid hormone receptor and osteocalcin transcripts in both types of differentiated stem cells in an HPR medium supplemented with osteogenic inducers. However, the upregulation level of alkaline phosphatase was relatively lower in differentiated MenSCs than that in differentiated BMSCs. We concluded that despite lower osteogenic differentiation capacity of MenSCs compared to BMSCs, substitution of FBS with HPR could equalize the osteogenic differentiation of MenSCs. Therefore, by taking advantage of osteogenic driving potential of HPR, MenSCs could be introduced as an apt and safe alternative to BMSCs for bone tissue-engineering purposes.