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Ehsan Hashemi,1– 3 Omid Akhavan,4 Mehdi Shamsara,1,2 Saeid Ansari Majd,2 Mohammad Hossein Sanati,5 Morteza Daliri Joupari,1,2 Abbas Farmany6 1Animal Biotechnology Department, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran; 2National Research Center for Transgenic Mouse, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran; 3Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran; 4Department of Physics, Sharif University of Technology, Tehran, Iran; 5Medical Genetics Department, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran; 6Dental Research Center, Hamadan University of Medical Sciences, Hamadan, IranCorrespondence: Morteza Daliri Joupari; Abbas Farmany Tel +98 21 4458-0340Fax +98 21 44580393Email daliri@nigeb.ac.ir; a.farmany@ut.ac.irBackground: Unique properties of graphene and its derivatives make them attractive in the field of nanomedicine. However, the mass application of graphene might lead to side effects, which has not been properly addressed in previous studies, especially with regard to its effect on the cell cycle.Methods: The effect of two concentrations (100 and 200 μg/mL) of nano- and microsized graphene oxide (nGO and mGO) on apoptosis, cell cycle, and ROS generation was studied. The effect of both sizes on viability and genotoxicity of the embryonic fibroblast cell cycle was evaluated. MTT and flow cytometry were applied to evaluate the effects of graphene oxide (GO) nanosheets on viability of cells. Apoptosis and cell cycle were analyzed by flow cytometry.Results: The results of this study showed that GO disturbed the cell cycle and nGO impaired cell viability by inducing cell apoptosis. Interestingly, both nGO and mGO blocked the cell cycle in the S phase, which is a critical phase of the cell cycle. Upregulation of TP53-gene transcripts was also detected in both nGO- and mGO-treated cells compared to the control, especially at 200 μg/mL. DNA content of the treated cells increased; however, because of DNA degradation, its quality was decreased.Conclusion: In conclusion, graphene oxide at both nano- and micro-scale damages cell physiology and increases cell population in the S phase of the cell cycle.Keywords: apoptosis, cell cycle, fibroblast cell, graphene, TP53 gene

Ehsan Hashemi,1,2 Hossein Mahdavi,3 Jafar Khezri,1 Farideh Razi,2,4 Mehdi Shamsara,1 Abbas Farmany5 1National Research Center for Transgenic Mouse & Animal Biotechnology Division, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran; 2Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran; 3School of Chemistry, College of Science, University of Tehran, Tehran, Iran; 4Diabetes Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran; 5Dental Implant Research Center, Hamadan University of Medical Sciences, Hamadan, IranCorrespondence: Abbas FarmanyDental Implant Research Center, Hamadan University of Medical Sciences, Hamadan, IranEmail a.farmany@ut.ac.irBackground: Beyond viral carriers which have been widely used in gene delivery, non-viral carriers can further improve the delivery process. However, the high cytotoxicity and low efficiency impedes the clinical application of non-viral systems. Therefore, in this work, we fabricated polyethylene glycol (PEG) coated, calcium doped magnetic nanograin (PEG/Ca(II)/Fe3O4) as a genome expression enhancer.Methods: Monodisperse magnetic nanograins (MNGs) with tunable size were synthesized by a solvothermal method. The citrate anions on the spherical surface of MNGs capture Ca2+ ions by an ion exchange process, which was followed by surface capping with PEG. The synthesized PEG/Ca(II)/Fe3O4 was characterized using Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) spectra, vibrating sample magnetometer (VSM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). MTT test was utilized to assess the toxicity of PEG/Ca(II)/Fe3O4. Real time qPCR was applied for quantification of gene expression.Results: DLS spectra and TEM images confirmed a thin layer of PEG on the nanocarrier surface. Shifting the zeta potential in the biological pH window from −23.9 mV (for Fe3O4) to ≈ +11 mV (for PEG/Ca(II)/Fe3O4) confirms the MNGs surface protonation. Cytotoxicity results show that cell viability and proliferation were not hindered in a wide range of nanocarrier concentrations and different incubation times.Conclusion: PEGylated calcium doped magnetic nanograin enhanced PUC19 plasmid expression into E. Coli and GFP protein expression in HEK-293 T cells compared to control. A polymerase chain reaction of the NeoR test shows that the transformed plasmids are of high quality.Keywords: gene expression, calcium doped magnetic nanograins, cytotoxicity

Designing and producing a proper fusion construction is the most important problem of producing large quantities of a properly folded functional protein. This construction should have all necessary components of a real gene. A good designed fusion gene construction could be cloned into a good and suitable host. Clostridium perfringens is an important pathogen of humans and livestock and produces numerous toxins including epsilon and beta which are responsible for severe diseases. In the present study a new construction containing Clostridium perfringens type D epsilon toxin gene and type B beta toxin gene was designed. At the first step two pairs of primers were used for these genes amplification. At the next step epsilon forward and beta reveres primers were used to produce a chimeric gene containing amplified partial cds of etxD and partial cds of cpbB which are linked together by the AEAAAKEAAAKA fragment as a small linker. The method was based on fusion PCR and using of Pfu DNA polymerase, which has a proofreading activity. The fusion gene inserted into pJET1.2blunt and cloned into E.coli strain TOP10. Based on the latest information, this is the first design and cloning of epsilon-beta fusion gene and also this is the first time that PCR fusion strategy is used for Clostriadial gene fusion, which could be used for development of a recombinant epsilon-beta fusion protein vaccine. This construction also could serve as a model for development and production of novel fusion protein for other potential proteins and toxins.

Background and Objective: Ovarian cancer is the fifth common cancer among women and the number of new cases is increasing. Valproic acid is a histone deacetylase inhibitor effectively used to treat epilepsy and bipolar disease. Recently, this compound has attracted attention as an anti-cancer agent. Bim is one of the most important genes of mitochondrial pathway of apoptosis, and it plays an important role in the biology of cancer. Expression of this gene is greatly reduced in ovarian cancer. This study was done to evaluate the effect of valproic acid on the viability of ovarian cancer cells, apoptosis and Bim gene expression in A2780 line. Methods: In this experimental study, the human ovarian cancer cells (A2780) were grown in RPMI- 1640 medium in appropriate culture conditions. The cells were treated by various concentrations valproic acid (1-30 mM) and were incubated for 24, 48 and 72 hours. After the incubation of period, cell viability was investigated using MTT. Apoptosis was analyzed by flow-cytometry method in the cells were treated by valproic acid. The Real time PCR test was used to assess the effect of this drug on the expression of Bim gene. Results: The results of MTT assay showed that valproic acid reduced the viability of A2780 cells, and this effect was time and dose-dependent. The reduction of cell viability at 30 mM concentration and 72 hours after treatment, was maximum and statistically significant (P<0.05). Exposure to valproic acid significantly increased the percentage of apoptotic cells (P<0.05). Also, Valproic acid significantly increased the expression of Bim (P<0.05). Conclusion: Valproic acid reduced viability in ovarian cancer cell line A2780. Valproic acid increased cell death by altering the expression of genes involved in apoptosis in ovarian cancer cell line A2780. [ABSTRACT FROM AUTHOR]

Introduction: For embryo preservation in the long-term, cryopreservation is one of the undeniable technologies in assisted reproductive technologies. Exposure to a variety of cellular stressors, like culture media and high concentrations of cryoprotectants, can induce changes in gene expression and apoptosis pattern. This study compared vitrified-warmed in vivo and in vitro embryos in terms of viability and expression of Bax and Bcl2 genes which are involved in apoptosis. Materials and Methods: In experiment 1, about 300 in vivo blastocysts divided into 3 groups. Group A, vitrified/warmed blastocysts, group B, blastocysts just exposed to vitrification/warming solutions as toxicity test and finally group C, non-treated blastocysts as control. In experiment 2, same number of IVF-derived blastocysts divided into the same categories. Survival and hatching rates of blastocysts in all groups were assessed. Expression of Bax and Bcl2 was evaluated by Real Time PCR technique. Results: The proportion of hatching and hatched blastocysts in in-vivo blastocyst was notably higher than those observed in IVF-derived counterpart. No significant difference was observed in expression of Bax and Bcl2 genes between treated groups. Conclusion: These data suggest that vitrification of IVF-derived blastocysts can be used as an efficient method for blastocysts preservation. [ABSTRACT FROM AUTHOR]

Introduction: Nowadays, in vitro fertilization (IVF) is a routine and widely accepted treatment for infertility. IVF-derived embryos are exposed to many cellular stresses like changes in pH and temperature during the culture period. Cellular stresses are associated with changes in gene expression and thus activation of the apoptotic process. The aim of the present study was to compare the expression level of apoptotic specific gene, P53 in IVF-derived embryos with in vivo embryo counterpart. Materials and Methods: In this experiment, 420 IVF-derived blastocysts (treated group) and in vivo produced blastocysts (control group) were used. The survival and hatching rates of blastocysts were evaluated in these groups. Expression of p53 gene in both IVF and in vivo embryos were evaluated using Real-time PCR. Results: A decrease was observed in survival rate in treated group than control group (97.14 vs. 92.89). Also the hatching rate of blastocysts decreased significantly compared with control group (50% vs. 60.10%). P53 expression was increased in treated group in comparison with control group, but this increase was not statistically significant (p>0.05). Conclusion: The findings of this study indicate that in vitro fertilization as a successful approach for infertility treatment. Although the hatching and survival rates of IVF-derived blastocysts were decreased, our results revealed that in vitro fertilization do not make undesired effects on P53 gene expression. [ABSTRACT FROM AUTHOR]

Introduction: In vitro fertilization (IVF) is one of the assisted reproductive technologies used to help infertility treatment. In vitro culture of preimplantation embryos is associated with changes in gene expression. Exposure of preimplantation embryos to a variety of cellular stresses like culture media can induce apoptosis. It is however, not known if the method of fertilization affects the pattern of gene expression. We compared gene expression of IVF-derived mouse blastocysts versus in vivo produced blastocysts. The purpose of this study was to investigate the effect of in vitro fertilization on the expression of P53 gene which is involved in apoptosis process. Material and Methods: IVF-derived blastocysts were considered as group 1 and in vivo blastocysts as group 2. Expression of P53 gene in IVF and in vivo embryos were assessed with real-time PCR. Results: Our results showed no significant changes in the expression of P53 gene between two groups. Conclusion: In vitro fertilization can be used as an efficient and feasible method for infertility treatment. [ABSTRACT FROM AUTHOR]

Introduction: Since the birth of the first baby using in vitro fertilization (IVF) in 1978, enormous changes in the field of reproductive biology and infertility treatment have been established. Although IVF is considered as a safe technique but studies have shown that during IVF, some stresses induced by osmosis, oxygen, temperature and pH changes in ectopic conditions can cause morphological, genetic and epigenetic changes in embryos derived from IVF compared to in vivo. The purpose of this study was to assess the effect of IVF on embryo quality regarding the expression level of Oct4 gene. This gene is effective in the pluripotency of blastocyst inner cell mass. Materials and Methods: In this experiment 3.5 to 4.5 days old mouse embryos were used in both treated and control groups. Expression level of Oct4 gene was evaluated using Real-time PCR technique in IVF derived blastocyst (treated group) and In vivo blastocyst (control group). Results: Oct4 gene expression levels increased in the treated group compared to the control group, but this increase was not significant (p>0.05). Conclusion: According to the results, in vitro fertilization does not have undesired effects on Oct4 gene expression in mouse blastocyst. [ABSTRACT FROM AUTHOR]

Introduction: Based on previous studies, manual puncture of trophectoderm (TE) of mouse blastocyst using a microneedle prior to vitrification increases survival rate. But this might be invasive and induce TE cell damage. Therefore, we examined the effect of artificial collapse (AC) of blastocoele on viability and quality of embryos through expression of Cdx2 as a TE specific marker. Materials and methods: 3.5 to 4.5 days old embryos were obtained from superovulated female mice and divided randomly in AC-treated and non-treated groups. In first group blastocysts were mechanically punctured with a microneedle. Survival capacities of collapsed blastocysts were assessed on the basis of their ability to re-expansion and leave the zona pellucida (hatching) 3 and 12 hours after AC. In addition, quantitative expression of Cdx2 was performed in both groups by Real-time PCR technique. Results: The re-expansion and hatching rate of collapsed blastocysts were significantly improved. In the first group, expression of cdx2 gene increased in compare with second group. Conclusion: Our results reveal that using AC of blastocoele cavity would be a useful approach to improve pregnancy outcome. [ABSTRACT FROM AUTHOR]

Introduction: Embryo cryopreservation is possible in all stages of pre-implantation, but according to some studies, the survival rate of cryopreserved blastocyst is lower than the other stages. This problem could be due to the fluid-filled cavity of blastocyst that provides a good ground for ice crystals formation and cell structure damages. Artificial collapse of blastocyst cavity is one of the assisted reproductive technologies that can diminish this problem by reducing the volume of blastocoelic fluid. But the risk of mechanical damages to blastomers is possible during this technique. The purpose of this study was to investigate the effect of artificial collapse of blastocyst on embryo quality through evaluation of Nanog gene expression that is effective in the pluripotency of inner cell mass. Materials and Methods: 3.5-4.5 days old In vivo mouse embryos were divided in treated and control groups randomly. Blastocysts were collapsed by using a microneedle in treated group. The Nanog gene expression assessed in treated group and fresh blastocysts as control group by Real-time PCR technique. Results: Nanog gene expression was increased in treated group in comparison with control group, but this increase was not statistically significant. Conclusion: Our results revealed that artificial collapse of blastocyst do not make undesired effects on Nanog gene expression. [ABSTRACT FROM AUTHOR]

Introduction: It is generally accepted that mammalian preimplantation embryos are sensitive to their surrounding environment and culture conditions in case of in vitro studies. Culture conditions can affect gene expressions which are associated with embryo quality. Therefore, we compared the expression of primitive endoderm layer markers (Gata6, Grb2) and development of mouse blastocysts produced by in vitro fertilization (IVF) versus in vivo produced blastocysts. Materials and Methods: For IVF group, oocytes were isolated from the superovulated females and fertilized in vitro by capacitated sperm obtained from the cauda epididymis of male. The presumptive zygotes were cultured to the blastocyst stage. For control group, blastocysts were flushed out of the uterus on post mating day 3.5. Finally expression levels of Gata6 and Grb2 genes in both groups of blastocysts were analyzed by Real-time PCR. Results: In vitro blastocysts have a reduction in hatching rate compared with blastocysts generated in vivo (70.22% vs. 87.80%). Furthermore blastocysts produced by IVF had an increase in the expression levels of Gata6 and Grb2 when compared with the in vivo control embryos (p>0.05). Conclusion: Assisted hatching for in vitro produced embryos would be a useful approach to improve pregnancy outcome. [ABSTRACT FROM AUTHOR]

Contamination of aquatic food webs with nanomaterials poses a significant ecological and human health challenge. Ingestion of nanomaterials alongside food disrupts digestion and impairs physiological processes, with potential consequences for organism fitness and survival. Complex interactions between nanomaterials and biota further exacerbate the issue, influencing life-history strategies and ecosystem dynamics. Accumulation of nanomaterials within autotrophic and detritus-based food webs raises concerns about biomagnification, especially for top-level consumers and seafood-dependent human populations. Understanding the extent and impact of nanomaterial contamination on aquatic biota is crucial for effective mitigation strategies. To address this challenge, we conducted a comprehensive study evaluating the bioaccumulation effects of graphene oxide (GO), a commonly used nanomaterial, within an aquatic food chain. Using a gnotobiotic freshwater microcosm, we investigated the effects of micro- and nano-scale GO sheets on key organisms: green algae (Chlorella vulgaris), brine shrimp (Artemia salina), and zebrafish (Danio rerio). Two feeding regimes, direct ingestion and trophic transfer, were employed to assess GO uptake and transfer within the food web. Direct exposure involved individual organisms being exposed to either nano- or micro-scale GO sheets, while trophic transfer involved a sequential exposure pathway: algae exposed to GO sheets, artemias feeding on the algae, and zebrafish consuming the artemias. Our study provides critical insights into nanomaterial contamination in aquatic ecosystems. Physicochemical properties of GO sheets, including ζ-potential and dispersion, were influenced by salt culture media, resulting in aggregation under salt conditions. Microscopic imaging confirmed the bioaccumulation of GO sheets within organisms, indicating prolonged exposure and potential long-term effects. Notably, biodistribution analysis in zebrafish demonstrated the penetration of nano-sized GO into the intestinal wall, signifying direct interaction with vital organs. Exposure to GO resulted in increased zebrafish mortality and impaired reproductive performance, particularly through trophic transfer. These findings emphasize the urgent need to address nanomaterial contamination in aquatic food webs to protect ecosystem components and human consumers. Our study highlights the importance of developing effective mitigation strategies to preserve the integrity of aquatic ecosystems, ensure resource sustainability, and safeguard human well-being. In conclusion, our study provides crucial insights into the impact of nanomaterial pollution on aquatic biota. By recognizing the challenges posed by nanomaterial contamination and implementing targeted interventions, we can mitigate the adverse effects, preserving the integrity of aquatic ecosystems and safeguarding human health., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Probiotics offer health advantages when consumed in adequate quantities. As ongoing research identifies promising new strains, ensuring their viability and functionality through simple preservation methods is vital for success within the probiotic industry. This study employed a factorial design to investigate the combined effects of four cryoprotectants [C1: MRS broth + 14 % (w/v) glycerol, C2: Aqueous solution containing 4 % (w/v) trehalose, 6 % (w/v) skimmed milk, and 4 % (w/v) sodium glutamate, C3: Aqueous solution containing 10 % (w/v) skimmed milk and 4 % (w/v) sodium glutamate, C4: Aqueous solution containing 4 % (w/v) sucrose, 6 % (w/v) skimmed milk, and 4 % (w/v) sodium glutamate] and three methods of preservation (P1: -86 °C freezing, P2: -196 °C liquid nitrogen freezing, and P3: storing at 4 °C after lyophilization) on the cell viability of three potentially probiotic strains over 12 months. Pediococcus sp P15 and Weissella cibaria ml6 had the highest viability under treatments C3 and C2, after 12 months of storage, respectively. Meanwhile, Lactococcus lactis ml3 demonstrated the highest viability in both treatments C2 and C4 (P ≤ 0.05). According to the results freezing, either P1 or P2, is the most effective preservation method for P. sp P15 and W. cibaria ml6. Meanwhile, L. lactis ml3 showed the highest colony count under treatment (P1) after 12 months of storage (P ≤ 0.05). Among the tested conditions, P. sp P15 and L. lactis ml3 exhibited the highest viability and bile salt resistance when stored under P1C1. For W. cibaria ml6, the optimal storage condition was P2C2 (frozen in liquid nitrogen with cryoprotectant C2)., (Copyright © 2024. Published by Elsevier Inc.)

Purpose: Fetal hemoglobin (HbF) upregulation is a mitigating factor in β-hemoglobinopathies therapy like β-thalassemia and sickle cell diseases. Finding molecular mechanisms and the key regulators responsible for globin switching could be helpful to develop effective ways to HbF upregulation. In our prior in silico report, we identified a few factors that are likely to be responsible for globin switching. The goal of this study is to experimentally validate the factors., Methods: We established K562 cell line with BCL11A knock down leading to increase in HBG1/2 using CRISPR/Cas9 system. Then, using quantitative polymerase chain reaction (qPCR), we determined the expression level of the factors which were previously identified in our prior in silico study., Results: our analysis showed that BCL11A was substantially knocked down, resulting in the upregulation of HBG1/2 in the BCL11A-ablated K562 cells using CRISPR/Cas9 system. Additionally, the experimental data acquired in this study validated our prior bioinformatics findings about three potentially responsible genes for globin switching, namely HIST1H2Bl, TRIM58, and Al133243.2., Conclusion: BCL11A is a promising candidate for the treatment of β-hemoglobinopathies, with high HbF reactivation. In addition, HIST1H2BL, TRIM58 and Al133243.2 are likely to be involved in the mechanism of hemoglobin switching. To further validate the selected genes, more experimental in vivo and in vitro studies are required., Competing Interests: The authors have no conflict of interest., (©2023 The Authors.)

There are numerous applications for recombinant antibodies (rAbs) in biological and toxicological research. Monoclonal antibodies are synthesized using genetic engineering and other related processes involved in the generation of rAbs. Because they can identify specific antigenic sites on practically any molecule, including medicines, hormones, microbial antigens, and cell receptors, rAbs are particularly useful in scientific research. The key benefits of rAbs are improved repeatability, control, and consistency, shorter manufacturing times than with hybridoma technology, an easier transition from one format of antibody to another, and an animal-free process. The engineering of the host cell has recently been developed method for enhancing the production efficiency and improving the quality of antibodies from mammalian cell lines. In this light, genetic engineering is mostly utilized to manage cellular chaperones, decrease cell death, increase cell viability, change the microRNAs (miRNAs) pattern in mammalian cells, and glycoengineered cell lines. Here, we shed light on how genetic engineering can be used therapeutically to produce antibodies at higher levels with greater potency and effectiveness., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Developing mouse models of hemophilia A has been shown to facilitate in vivo studies to explore the probable mechanism(s) underlying the disease and to examine the efficiency of the relevant potential therapeutics. This study aimed to knockout (KO) the coagulation factor viii (fviii) gene in NMRI mice, using CRISPR/Cas9 (D10A/nickase) system, to generate a mouse model of hemophilia A. Two single guide RNAs (sgRNAs), designed from two distinct regions on NMRI mouse FVIII (mFVIII) exon 3, were designed and inserted in the pX335 vector, expressing both sgRNAs and nickase. The recombinant construct was delivered into mouse zygotes and implanted into the pseudopregnant female mice's uterus. Mutant mice were identified by genotyping, genomic sequencing, and mFVIII activity assessment. Two separate lines of hemophilia A were obtained through interbreeding the offspring of the female mice receiving potential CRISPR-Cas9-edited zygotes. Genomic DNA analysis revealed disruptions of the mfviii gene reading frame through a 22-bp deletion and a 23-bp insertion in two separate founder mice. The founder mice showed all the clinical signs of hemophilia A including; excessive bleeding after injuries, and spontaneous bleeding in joints and other organs. Coagulation test data showed that mFVIII coagulation activity was significantly diminished in the mFVIII knockout (FVIII KO ) mice compared to normal mice. The CRISPR/nickase system was successfully applied to generate mouse lines with the knockout fviii gene. The two novel FVIII KO mice demonstrated all clinical symptoms of hemophilia A, which could be successfully inherited. Therefore, both of the developed FVIII KO mouse lines are eligible for being considered as proper mouse models of hemophilia A for in vivo therapeutic studies.

Introduction: Different kinds of treatments have been developed to fight cancers. Low-level laser therapy (LLLT), also known as photobiomodulation therapy (PBMT), is a low-power monochromatic and coherent light that has been used successfully for healing injuries and combating malignancies. However, there are concerns about the application of LLLT to cancers due to the increased proliferation of some cancer cells after LLLT. Methods: This study investigated the effects of 650 nm and 870 nm lasers on the proliferation of HT29 colorectal cancer cell lines in vitro and in vivo . Results: The results showed that the laser with a wavelength of 870 nm did not meaningfully alter the proliferation of cultured cells. However, cell proliferation was promoted when the laser was applied within a wavelength of 650 nm. Treatment of HT29-derived tumors in nude mice with the 650 nm laser resulted in the decline of the tumor progression rate compared to controls. This result was inconsistent with the proliferative effects of the laser on the cultured cells. Conclusion: Cell behavior in response to LLLT might be different between cell culture and xenograft models., Competing Interests: The authors state no conflicts of interest regarding this study., (Copyright © 2023 J Lasers Med Sci.)

The keratin-degrading bacterium Bacillus licheniformis secretes a keratinase with potential industrial interest. Here, the Keratinase gene was intracellularly expressed in Escherichia coli BL21(DE3) using pET-21b (+) vector. Phylogenetic tree analysis showed that KRLr1 is closely related to Bacillus licheniformis keratinase that belongs to the serine peptidase/subtilisin-like S8 family. Recombinant keratinase appeared on the SDS-PAGE gel with a band of about 38 kDa and was confirmed by western blotting. Expressed KRLr1 was purified by Ni-NTA affinity chromatography with a yield of 85.96% and then refolded. It was found that this enzyme has optimum activity at pH 6 and 37°C. PMSF inhibited the KRLr1 activity and Ca 2+ and Mg 2+ increased the KRLr1 activity. Using keratin 1% as the substrate, the thermodynamic values were determined as K m 14.54 mM, k cat 912.7 × 10 -3 (S -1 ), and k cat /K m 62.77 (M -1 S -1 ). Feather digestion by recombinant enzyme using HPLC method, showed that the amino acids cysteine, phenylalanine, tyrosine and lysine had the highest amount compared to other amino acids obtained from digestion. Molecular dynamics (MD) simulation of HADDOCK docking results exhibited that KRLr1 enzyme was able to interact strongly with chicken feather keratine 4 (FK4) compared to chicken feather keratine 12 (FK12). These properties make keratinase KRLr1 a potential candidate for various biotechnological applications., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Rahimnahal, Meimandipour, Fayazi, Asghar Karkhane, Shamsara, Beigi Nassiri, Mirzaei, Hamblin, Tarrahimofrad, Bakherad, Zamani and Mohammadi.)

Introduction: Spermatogonial stem cells (SSCs) offer remarkable competencies for animal reproduction and overcoming human disease as a result of their differentiation capability. We evaluated the effect of small molecule pifithrin-mu (PFT-µ), a well-known inhibitor of P53 on SSC biological processes such as viability, apoptosis, and gene expression pattern., Methods: The SSCs were isolated from the testes of adult NMRI mice and then cultured in DMEM/F12 medium containing 10% FBS. Then, they were characterized by the immunocytochemistry technique by high PLZF and low c-Kit expressions. SSC colony formation assay was carried out and their viability was estimated by methylthiazolyldiphenyl-tetrazolium bromide (MTT, or 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2H-tetrazolium bromide) assay upon exposure to PFT-µ (0, 0.6, 1.2, 2.5, and 5 µm). The apoptosis percentages were also measured using FACS analysis, and finally, Oct4 and Stra8 expression at mRNA levels was assessed using real-time quantitative PCR., Results: The 0.6 and 1.2 µm PFT-µ improved the viability of SSC based on MTT assay results; however, 2.5 and 5 µm PFT-µ reduced SSC viability compared with the control group. Moreover, PFT-µ at lower concentrations enhanced the colony size of SSCs and diminished their apoptosis. As well, exposure to PFT-µ upregulated Oct4 expression while downregulating the meiotic entry marker, Stra8., Conclusion: Based on findings, optimized concentrations of PFT-µ can decrease SSC apoptosis, and conversely potentiate their pluripotency and self-renewal capacities in vitro., (© 2023 The Author(s). Published by S. Karger AG, Basel.)

The main goals of medicine consist of early detection and effective treatment of different diseases. In this regard, the rise of exosomes as carriers of natural biomarkers has recently attracted a lot of attention and managed to shed more light on the future of early disease diagnosis methods. Here, exosome biogenesis, its role as a biomarker in metabolic disorders, and recent advances in state-of-art technologies for exosome detection and isolation will be reviewed along with future research directions and challenges regarding the manipulation and genetic engineering of exosomes for potential in vitro and in vivo disease diagnosis approaches., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Hadizadeh, Bagheri, Shamsara, Hamblin, Farmany, Xu, Liang, Razi and Hashemi.)

With the unexpected emergence of the novel 2019 Wuhan coronavirus, the world was faced with a sudden uproar that quickly shifted into a serious life-threatening pandemic. Affecting the lives of the global population and leaving drastic damage in various sections and systems, several measures have been constantly taken to tackle down this crisis. For instance, numerous vaccines have been developed in the past two years, some of which have been granted emergency use, thus providing sufficient immunity to the vaccinated individuals. However, the appearance of newly emerged SARS-CoV-2 variants with accelerated transmission and fatality has led the world towards another pandemic. Having undergone various mutations in genomic and/or amino acid profiles, some of the emerged variants of concern (VOCs) including Alpha, Beta, Gamma, and Delta have displayed immune evasion and pathogenicity even in the vaccinated population, hence raising concerns regarding the efficacy of current vaccines against new VOCs of COVID-19. Therefore, genomic investigations of SARS-CoV-2 mutations are expected to provide valuable insight into the evolution of SARS-CoV-2, while also determining the impact of different mutations on infection severity. This study was constructed with the aim of shining light on recent advances regarding mutations in major COVID-19 VOCs, as well as vaccination efficacy against those VOCs., Competing Interests: Conflict of interestsOn behalf of all authors, the corresponding author states that there is no conflict of interest., (© The Author(s), under exclusive licence to Tehran University of Medical Sciences 2022.)

Background: The octamer-binding transcription factor-4 (OCT4) is known as an established important regulator of pluripotency, as well as a genetic "master switch" in the self-renewal of embryonic stem and germ cells. OCT4B1 , one of the three spliced variants of human OCT4, plays crucial roles in the regulation of pluripotency and stemness., Objectives: The present study developed a transgenic mouse model containing an OCT4B1 -expressing construct under the transcriptional direction of mouse mammary tumor virus promoter (pMMTV) to evaluate the role of OCT4B1 in the function of male germ cells in terms of fertility potential. Additionally, the effect of ectopic OCT4B1 overexpression on endogenous OCT4 expression was examined in mouse embryonic stem cells (mESCs)., Material and Methods: The pMMTV-OCT4B1cDNA construct was injected into the pronuclei of 0.5-day NMRI embryos. Transgenic mice were identified based on the PCR analysis of tail DNA. Further, Diff-Quik staining was applied to assess sperm morphology, while the other sperm parameters were analyzed through a conventional light microscopic evaluation according to World Health Organization (WHO) criteria. The fertility rate was scored by using in vitro frtilization (IVF) method. Furthermore, mESCs was electroporated with the OCT4B1cDNA -containing constructs, followed by analyzing through employing semi-quantitative RT-PCR and western blotting., Results: The results demonstrated the changes in sperm morphology, as well as a statistically significant decrease in the other sperm parameters (count, viability, and motility) and fertility rate (p<0.05) in the transgenic mice compared with the control group. The assessment of the cause of the embryonic stem cell (ESC) death following transfection revealed a significant reduction in the endogenous OCT4 expression at both mRNA and protein levels in the transfected mESCs compared to the control ones., Conclusion: In general, the in vivo results suggested a potential role of OCT4B1 in the spermatogenesis process. These results represented that the overexpression of OCT4B1 may induce its role in spermatogenesis and fertility rate by interfering endogenous OCT4 expression. However, further studies are required to clarify the mechanisms underlying OCT4B1 function., (Copyright: © 2021 The Author(s); Published by Iranian Journal of Biotechnology.)

In recent decades, bone tissue engineering has had an effective role in introducing orthopedic implants. In this regard, polymeric scaffolds reinforced with bioactive nanomaterials can offer great potential in tissue engineering implants for replacing bone loss in patients. In this study, the thermally induced phase separation method was used to fabricate three-dimensional highly porous scaffolds made of layered double hydroxide (LDH)/polycaprolactone (PCL) nanocomposites with varied LDH contents ranging from 0.1 wt.% to 10 wt.%. The Phase identification, morphology, and elemental composition were studied using X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy, respectively. Interconnected pores ranging from 5 to 150 µm were detected in all samples. The results revealed that the inclusion of LDH to PCL scaffold reinforced mechanical strength and compressive modulus increased from 0.6418 to 1.3251 for the pure PCL and PCL + LDH (1 Wt.%) scaffolds, respectively. Also, thermal stability, degradation rate, and biomineralization especially in comparison with the pure PCL were enhanced. Adhesion, viability, and proliferation of human bone marrow-derived mesenchymal stem cells (hBMSCs) seeded on PCL + LDH scaffolds were improved as compared to the pure PCL. Furthermore, the addition of LDH resulted in the increased mineral deposition as well as expression of ALP and RUNX2 osteogenic genes in terms of differentiation. All in all, our findings revealed that PCL + LDH (1 Wt.%) scaffold might be an ideal choice for 3D scaffold design in bone tissue engineering approaches., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Enderami, Shafiei, Shamsara, Enderami and Rostamian Tabari.)

Human papillomavirus infections are associated with most cervical cancers, which are the fourth most common cancer in women. HPV-E6 protein binds to protein p53 and inhibits its function, leading to the switching of normal cells toward cancer cells. Here, we disrupted the HPV-E6 gene and investigated its effects on the proliferation and apoptosis of HeLa cells. The HPV18-E6 gene was targeted with two designed sgRNAs cloned into an AAV-CRISPR-based plasmid. The AAV-E6-CRISPR/Cas9 virions were prepared and titrated in HEK293t cells. The cleavage created in the HPV-E6 gene was detected using the T7E1 assay. Cell cycle profiling, MTT assay, and annexin V/PI staining were performed. Also, the p53 protein level was measured by Western blotting. Our data showed that disruption of the HPV-E6 gene led to increased cell apoptosis and decreased cell proliferation. A significant accumulation of infected cells in sub-G1 phase was observed in the cell profiling assay. Also, HPV-E6 gene disruption resulted in a significant increase in the level of P53 protein. Our findings indicated that AAV-mediated delivery of CRISPR/Cas9 can effectively target the HPV-E6 gene in HeLa cells, and its antiproliferative effects may provide therapeutic benefits of local administration of this gene-editing system for HPV-related cervical cancers., (© 2022. The Author(s).)

Background: Reactivation of HbF is a potential strategy to ameliorate symptoms of hemoglobinopathies such as sickle cell disease and b-thalassemia. After birth, there is a switch from fetal to adult hemoglobin, for which the molecular mechanisms and key regulators await further understanding in order to develop effective methods for HbF reactivation. Bcl11a, one of the major HbF reactivation regulators, demonstrates no significant changes at transcriptional levels in F erythroblasts compared to the non-HbF expressing cells. Therefore, it is possible that posttranscriptional regulation and epigenetic effects, for which the miRNAs play an important role, are the primary causes of the decreased Bcl11a protein level in adult erythroblasts., Objective: This paper aims to determine the differentially expressed mRNAs and miRNAs of erythroblasts in HSCs from the fetal liver and bone marrow., Methods: Raw high-throughput sequencing data (GSE110936, GSE90878) was downloaded from Gene Expression Omnibus (GEO) database. After RNAseq analysis, several data sets and tools were used to select key genes and examine selection validation., Results: We selected 42 DEmRNAs and nine DEmiRs, including hsa-let-7f-5p, hsa-miR-21-5p, hsamiR- 22-3p, hsa-miR-126-5p, hsa-miR-146b-5p, hsa-miR-181a-5p, hsa-miR-92a-3p, hsa-miR-25-3p and hsa-miR-191-5p. Furthermore, hub genes including hist1h2bl, al133243.2, trim58, abcc13, bpgm, and fam210b were identified in the coexpression network, as well as RPS27A in the PPI network. Functional analysis revealed that these DEmRNAs and DEmiRs might play a role in gene expression regulation at multiple levels. Gene set enrichment analysis, in particular, revealed a possible role for genes in the globin switching process., Conclusion: According to our findings, a number of the DEmRNAs and DEmiRs may play significant roles in globin switching regulation and thus have the potential to be applied for HbF reactivation., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Leukemia inhibitory factor (LIF) is an essential cytokine for blastocyst implantation. This study evaluated the effect of LIF inhibition on the blockage of embryo implantation. A truncated mouse LIF (tmLIF) was designed and expressed in E. coli. The protein expression was optimized using different culture media and inducers. To block pregnancy, the mice were immunized by the purified protein via maternal injection of the protein or in utero injection of the anti-LIF serum. The expression of implantation-relevant genes was quantified in the uterine tissue. The results showed that the protein was expressed in aggregated form in E. coli. The highest yield of protein was produced in the M9 medium. The insoluble protein was completely dissociated by SDS and 2-ME combination, but not by urea. The maternal immunization reduced the number of offspring, but not significantly. Instead, in utero injection of the anti-LIF serum prevented the blastocyst implantation. Gene expression analyses showed decrease of Jam2, Msx1and HB-EGF genes and increase of Muc1 gene as the result of intrauterine administration of the anti-LIF serums. In conclusion, SDS-mediated solubilization of inclusion bodies was compatible with in vivo studies. The intrauterine administration of anti-LIF serum could prevent mouse pregnancy. This indicates that in utero application of LIF antibodies might be used as a contraceptive., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Vimentin, an intermediate filament of mesenchymal cells, is upregulated in epithelial-mesenchymal transition (EMT) and has a main role in cancer metastasis. As a new strategy to control metastatic outgrowth, EMT markers are generally inhibited using some drugs or specific siRNA. In this study, AGS gastric cancer cells were treated with metformin and vimentin-specific siRNA (vim-siRNA) for 48 h. The impact of metformin and vim-siRNA on vimentin downregulation in AGS cells were analyzed by quantitative PCR and Western blot. Following treatment with metformin and vim-siRNA, cell motility, migration and invasion abilities of AGS cells were also analyzed. The results showed that inhibition of vimentin due to metformin was comparable with the vim-siRNA. Furthermore, wound-healing and invasion assays showed a significant decrease in migration and invasion of AGS cells following metformin and vim-siRNA treatment. Our finding for the first time indicated that metformin can be an alternative to specific siRNA for inhibition of vimentin expression and migration of AGS cell line. Taken together, our data indicates that the use of metformin might have a priority to siRNA for inhibition of gastric cancer cell behaviors siRNA is more unstable and expensive than metformin, and needs special vehicles and delivery strategies for efficient transfection of cells. Further in vivo studies can reveal metformin's potential in inhibition of EMT and metastasis of cancer cells., Competing Interests: The authors declare that they have no conflict of interest.

Epithelial-mesenchymal transition (EMT) is a biological event, which critically regulates migration and invasion of cancer cells. EMT is regulated by several protein and nonprotein factors (such as noncoding RNAs). HOTAIR is an oncogenic long noncoding RNA that stimulates EMT in cancers. In the current study, we investigated the effect of metformin on EMT behavior and HOTAIR expression in MDA-MB-231 breast cancer cells. The minimal effective concentrations of metformin (10 and 20 mM) were obtained by the MTT test. Cell migration and invasion in the metformin-containing medium were assayed in the scratch assay and transwell test. Meaningful decreases in both cell migration and invasion were observed in the presence of metformin. Vimentin, snail, β-catenin, and HOTAIR transcripts were quantified by real-time polymerase chain reaction (PCR). Reduction in the expression of vimentin, β-catenin, and HOTAIR was detected as the result of metformin treatment, but the snail showed a constant expression. Western blottingrevealed the downregulation of vimentin and β-catenin proteins. HOTAIR promoter methylation pattern was also investigated in metformin-exposed cells using bisulfite sequencing PCR which the result showed differences in the methylation profile of CpG islands between the treated and untreated cells. In conclusion, metformin modulated oncogenic expression of the HOTAIR gene in the MDA-MB-231 cells. This downregulation was associated with the modification of promoter methylation patterns. Since HOTAIR induces EMT in breast cancer, HOTAIR decline might be one of the mechanisms by which metformin reverses EMT., (© 2020 Wiley Periodicals LLC.)

Despite its convenience and precision, CRISPR-based gene editing approaches still suffer from off-target effects and low efficiencies, which are partially rooted in Cas9, the nuclease component of the CRISPR/Cas9 system. In this study, we showed how mouse genome editing efficiency can be improved by constitutive and inheritable expression of Cas9 nuclease. For this goal, a transgenic mouse line expressing the Cas9 protein (Cas9-mouse) was generated. For in vitro assessment of gene editing efficiency, the Cas9-mice were crossed with the EGFP-mice to obtain mouse embryonic fibroblasts (MEF) expressing both EGFP and Cas9 (MEF Cas9-EGFP ). Transfection of these cells with in vitro transcribed (IVT) EGFP sgRNA or phU6-EGFP sgRNA plasmid led to robust decrease of Mean Fluorescent Intensity (MFI) to 8500 ± 1025 a.u. and 13,200 ± 1006 a.u. respectively. However, in the control group, in which the MEF EGFP cells were transfected with a pX330-EGFP sgRNA plasmid, the measured MFI was 16,800 ± 2254 a.u. For in vivo assessment, the Cas9-zygotes at two pronuclei stage (2PN) were microinjected with a phU6-Hhex sgRNA vector and the gene mutation efficiency was compared with the wild-type (WT) zygotes microinjected with a pX330-Hhex sgRNA plasmid. The analysis of born mice showed that while the injection of Cas9-zygotes resulted in 43.75% Hhex gene mutated mice, it was just 15.79% for the WT zygotes. In conclusion, the inheritable and constitutive expression of Cas9 in mice provides an efficient platform for gene editing, which can facilitate the production of genetically-modified cells and animals., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest in the publication., (© King Abdulaziz City for Science and Technology 2021.)

Cancer stem cells (CSCs) are a small subset of cancer cells responsible for self-renewal activity, drug resistance, and tumor recurrence. CSCs have been derived from diverse tumors and cell lines. The expression of stemness markers has been identified in CSCs. Oct4 is a well-established transcription factor expressed in stem cells and CSCs. In this study, we isolated and characterized breast CSC-like cells from murine MC4-L2 cells by Oct4 promoter-mediated activity. The MC4-L2 cells were electroporated by a plasmid expressing puromycin resistance (Puro R ) gene from the Oct4 promoter and then selected by puromycin. The isolated cells were named as the MC4-L2 puro cells and characterized for CSCs properties. Immunostaining indicated CD44 high and CD24 high phenotype for the MC4-L2 and MC4-L2 puro cells. The enhanced expression of stem cell markers was detected in the puromycin-selected cells compared with the parental cells. Moreover, the isolated cells only grew up in sphere-formed shape in low attachment plates. Serial dilution transplantation in syngeneic mouse models showed increased tumorigenicity of the MC4-L2 puro cells, as they induced new tumors when injected into the mammary fat pad as few as 10 4 cells. In conclusion, we designed a novel genetic construct, which allows the isolation of Oct4-positive cells in a cancer population by a simple selection step in a puromycin-containing medium. Transfection of this construct into the MC4-L2 cells resulted in growing a subpopulation of cells having tumor-initiating cell characteristics. To the best of our knowledge, this is the first report on the isolation of CSC-like cells from the mouse breast cancer MC4-L2 cells., (© 2020 Wiley Periodicals, Inc.)

Immunotherapy is a promising approach for specific targeting of cancer cells. Leukemia inhibitory factor (LIF) regulates several features of cancers and cancer stem cells (CSCs) through binding to LIF receptor (LIFR). In this study, we investigated the consensus of LIF and LIFR immunization on the growth of mouse mammary tumors. For this purpose, mouse LIF and LIFR were designed as truncated proteins, expressed in E. coli and then injected to mice as individual and mixed antigens. The results showed the production of neutralizing antibodies and secretion of interferon-γ and interleukin-2 in response to immunization. In continue, the immunized mice were subjected for tumor formation challenge by inoculation of the breast CSCs derived from MC4-L2 cells. Development of the breast tumors was observed in all the control mice, while the tumors appeared in 75% of animals in the LIF group. LIFR injection, individually or in combination with LIF, strongly inhibited the tumor growth to only 25% of the mice. Moreover, a delay in tumor appearance was observed in the immunized mice compared to the controls. Immunostaining of the tumor sections confirmed the expression of LIF and LIFR. In conclusion, LIF and LIFR might be effective targets for immunotherapy of the tumors that express these proteins.

Background and Purpose: Mitochondrion is the main indicator of oocyte quality and one of the components of oocyte, which is sensitive to oxidative damage during the maturation process. Mitoquinone mesylate (MitoQ) is a strong antioxidant targeting mitochondria as well as anti-apoptotic agent. However, the effect of MitoQ on the quality of oocytes during in vitro maturation (IVM) is still unknown., Objectives: This study investigated the possible effects of MitoQ on maturation and developmental competency in mice oocytes., Materials and Methods: The oocytes were collected at germinal vesicle stage from 6-8-week old female NMRI mice and then cultured in TCM-199 medium supplemented with 0, 0.01, 0.02 and 0.04 µM MitoQ. The sham group was treated with DMSO (0.01% v.v). Then intracellular Glutathione (GSH), reactive oxygen species (ROS) levels, mitochondria membrane potential (ΔΨm), as well as in vitro fertilization (IVF) rate in the 18-20 h matured oocytes and metaphase II (MII) oocytes (in vivo-control), were assessed., Results: The results showed that between three dose of MitoQ, the 0.02 µM significantly increased nuclear maturation rate, GSH level, fertilization rate and blastulation (92.6, 231.7, 90.19 and 81.66%, respectively) than the in vitro -control (71.14, 152, 78.84 and 73.50%, respectively) and more comparable to that of the in vivo matured oocytes (100, 243.5, 92.10 and 83%, respectively). Also, the mitochondria membrane potential in the 0.02 µM MitoQ was significantly higher compared with those in the other groups (4.4). However, the intracellular ROS level in 0.02 µM MitoQ was significantly decreased (38.72%) compared to in vitro -control (82.2%) and was similar to the in vivo-control (33.5%)., Conclusion: The results indicated that supplementation of IVM medium with MitoQ (specially 0.02 µM) enhance maturation and fertilization rate. In conclusion, MitoQ might be considered as a novel component that could be added to IVM media., (Copyright: © 2020 The Author(s); Published by Iranian Journal of Biotechnology.)

Dedifferentiation can be induced by small molecules. One of these small molecules used in this study in order to increase the plasticity of differentiation of stem cells was reversine. The objective of present study was to investigate the effect of different concentrations of reversine on the plasticity of ovine fetal bone-marrow mesenchymal stem cells (BM-MSCs). BM-MSCs were extracted from ovine fetal and cultured. Passaged-3 cells were evaluated for their differentiation potential into osteocytes and adipocytes cells. In the present study, BM-MSCs were culture plated in the presence of 0, 300, 600, 900 and 1200 nM of reversine. The number of viable cells was determined by MTT test after addition of different concentrations of reversine. Furthermore, expression of the nanog gene was evaluated. The culture without reversine was taken as the control group. Expression of nanog was analysed by immunocytochemistry. Multi-lineage differentiation showed that the BM-MSCs could be differentiated into adipose cells and osteocytes. Our results indicated that the addition of 1200 nM of reversine to medium significantly decreased overall proliferation compared to the other treatment groups ( p  > 0.05). Real-time PCR analysis showed that after addition of 600 nM of reversine significantly increased nanog expression compared to other treatments. All treatments received reversine were seen to be relative expression of nanog. Our findings confirm that low concentrations reversine increases the plasticity of ovine BM-MSCs., Competing Interests: Conflict of interestNone of the authors have any conflicts of interest to declare., (© Association of Clinical Biochemists of India 2018.)

L-glutaminase importance to use in the food industry and medicine has attracted much attention. Enzymes stability has always been a challenge while working with them. We heterologously expressed and characterized a novel stable L-glutaminase from an extremophile bacterium (Cohnella sp. A01, PTCC No: 1921). K m , V max , catalytic efficiency and specific activity of rSAM were respectively 1.8 mM, 49 µmol/min, 1851 1/(S.mM) and 9.2 IU/mg. Activation energy for substrate to product conversion and irreversible thermo-inactivation were respectively 4 kJ/mol and 105 kJ/mol from the linear Arrhenius plot. rSAM had the highest activity at temperature 50 °C, pH 8 and was resistant to a wide range of temperature and pH. In compare to the other characterized glutaminases, rSAM was the most resistant to NaCl. Mg 2+ , glycerol, DTT, and BME enhanced the enzyme activity and iodoacetate and iodoacetamide inhibited it. rSAM had only been partially digested by some proteases. According to the Fluorimetry and Circular dichroism analysis, rSAM in pH range from 4 to 11 and temperatures up to 60 °C had structural stability. A cysteine residue in the enzyme active site and a thiol bond were predicted upon the modeled tertiary structure of rSAM. Present structural studies also confirmed the presence of a thiol bond in its structure.

Differential expression of transgenes in transgenic animals is one of the main drawbacks of pronuclear injection. To overwhelm this issue, the genetic constructs are equipped with insulators. In this study, the consensus of exerting chicken hypersensitive site-4 ( cHS4 ) insulator was examined on the shield of phosphoglycerate kinase-1 ( Pgk - 1 ) promoter from the surrounding chromatin in transgenic mice. The PGK-EGFP cassette was flanked by insertion of three copies of the cHS4 insulators. Mouse zygotes' microinjection by the constructed cassette was resulted in the birth of nine transgenic founders (F0). Copy-number-dependent expression of the EGFP was investigated in the transgenic F1 offspring by fluorometry and real-time PCR. They showed no correlation between the expression level of transgene and gene copy number among the transgenic lines. Moreover, dissection of the EGFP -expressing mice revealed heterogeneous expression of the EGFP in the different organs. In conclusion, for the first time, these findings indicated that the cHS4 sequence is not a perfect insulator to fully protect the Pgk - 1 promoter from the side effects of integration site in transgenic mice and it needs probably to some additional elements of the cHS4 locus to reach this goal., Competing Interests: Conflict of interestThe authors declare no conflict of interest.

Animal models possess undeniable utility for progress on biomedical research projects and developmental and disease studies. Transgenic mouse models recreating specific disease phenotypes associated with β-hemoglobinopathies have been developed previously. However, traditional methods for gene targeting in mouse using embryonic stem cells (ESCs) are laborious and time consuming. Recently, CRISPR has been developed to facilitate and improve genomic modifications in mouse or isogenic cell lines. Applying CRISPR to gene modification eliminates the time consuming steps of traditional approach including selection of targeted ESC clones and production of chimeric mouse. This study shows that microinjection of a plasmid DNA encoding Cas9 protein along with dual sgRNAs specific to Hbb-bs gene (hemoglobin, beta adult s chain) enables breaking target sequences at exons 2 and 3 positions. The injections led to a knockout allele with efficiency around 10% for deletion of exons 2 and 3 and 20% for indel mutation., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Pancreatic and duodenal homeobox 1 (PDX1), a member of the homeodomain-containing transcription factor family, is a key transcription factor for pancreas development and mature β-cell function. In this study, induced overexpression of PDX1 resulted in producing susceptible cells for pancreatic differentiation and was well beneficial to enhance β-cell production, maturation, function, and survival. Induced PDX1 overexpression in harmony with a set of signaling molecules involves in guiding the signaling pathways toward pancreas development, leaded to high-efficient in vitro generation of ectopic insulin-producing cells (IPCs) with the effectively reduced number of polyhormonal cells and increased number of insulin (INS) single-positive cells. This strategy yielded 85.61% glucose-responsive insulin-positive cells in vitro, which was seven times higher than the basal level, and electron microscopy images revealed the presence of mature β-cell secretory granules. The generation of glucose-responsive insulin-secreting β-like cells from human-induced pluripotent stem cells (hiPSCs) in vitro would provide a promising approach to produce an unprecedented cell source for cell transplantation therapy in diabetes without the ethical obstacle of embryonic stem cells and would bypass immune rejection. These cells are an invaluable source for disease modeling, drug discovery, and pharmacogenomics studies as well.

Low oxygen concentrations during in vitro embryo development not only improving the embryo quality but also can lead to successful implantation. Yet, there is no investigation at the molecular level to indicate the association between increased implantation rate and invasive ability of blastocyst and its inner cell mass quality with in vitro culture under a hypoxic condition. Therefore, the present study was designed to investigate blastocyst formation, total cell number, hatching and implantation rates. In addition we assessed the transcription levels of invasion-(Mmp-9 and uPA) and pluripotency-related genes (Pou5f1, Nanog) in mouse blastocyst under hypoxic condition. In vivo two-cell embryos were randomly divided into two groups; 5% O 2 and 20% O 2 . Embryos were then cultured to the blastocyst stage and evaluated in terms of cellular parameters. The expression levels of selected genes were also analyzed both in experimental group and in vivo blastocysts recovered from uteri as control group. Results indicated the blastocyst formation, hatching and implantation rates were improved when the embryos were cultured in hypoxic condition. Furthermore, the expression levels of Mmp-9, Nanog and Pou5f1 showed an increase in 5% O 2 in comparison with 20% O2 group. In conclusion, it seems that hypoxic condition by increasing the quality and invasion ability of the blastocyst can improve implantation rate., (Copyright © 2018 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier B.V. All rights reserved.)

Background: Transgenic mice are being considered as invaluable tool in biological sciences towards comprehension of the cause of the genetic diseases. Manipulated embryonic stem (ES) cells are used to produce loss-of-function mutant mice. Microinjection of manipulated ES cells into blastocoel cavity, and morula fusion are the two main techniques in producing transgenic mice. So far, no reports have dealt with the comparison of these two methodologies provide., Objective: The object of this study was to determine advantages and disadvantages of knockout mouse creation protocols., Materials and Methods: Both blastocyst microinjection and morula aggregation were implemented to produce chimeric mice and the advantages and disadvantages of each technique were evaluated. For this, embryonic stem cells were transfected with a GFP-expression vector. In blastocyst microinjection technique, first transfected ES cell were cultured and appropriate colonies were selected. The cells were microinjected to blastocoel cavity of the expanded blastocyst. In morula aggregation technique, the transfected ES cell colonies were sandwiched between two naked morulas. After 16 h incubation in a 5% CO 2 at 37 °C the morulas and infected ES cell were aggregated to produce a new morula. All the injected blastocyst and aggregated morulas were transferred to uterus of foster mice. The new born mice were analyzed for chimera confirmation., Results: Five chimeric mice (21.75%) from morula aggregation and eight chimeric mice (63%) from blastocyst microinjection were born. The results indicated that both techniques can be used to generate chimeric mouse, however the success rate was higher in blastocyst microinjection., Conclusion: Morula fusion stands out where the required instrumentations are in place. Furthermore, the quality of ES cells plays a prominent role in the success rate. When the cell quality is low the blastocoel microinjection is recommended. The microinjection technique is more effective than morula aggregation.

Cisplatin resistance is one of the main limitations in the treatment of ovarian cancer, which is partly mediated by long noncoding RNAs (lncRNAs). H19 is a lncRNA involving in cisplatin resistance in cancers. Valproic acid (VPA) is a commonly used drug for clinical treatment of seizure disorders. In addition, this drug may display its effects through regulation of noncoding RNAs controlling gene expression. The aim of the present study was the investigation of VPA treatment effect on H19 expression in ovarian cancer cells and also the relation of the H19 levels with apoptosis and cisplatin resistance. Briefly, treatment with VPA not only led to significant increase in apoptosis rate, but also increased the cisplatin sensitivity of A2780/CP cells. We found that following VPA treatment, the expression of H19 and EZH2 decreased, but the expression of p21 and PTEN increased significantly. To investigate the involvement of H19 in VPA-induced apoptosis and cisplatin sensitivity, H19 was inhibited by a specific siRNA. Our results demonstrate that H19 knockdown by siRNA induced apoptosis and sensitized the A2780/CP cells to cisplatin-induced cytotoxicity. These data indicated that VPA negatively regulates the expression of H19 in ovarian cancer cells, which subsequently leads to apoptosis induction, cell proliferation inhibition, and overwhelming to cisplatin resistance. The implication of H19→EZH2→p21/PTEN pathway by VPA treatment suggests that we could repurpose an old drug, valproic acid, as an effective drug for treatment of ovarian cancer in the future.