yaser tahamtani

Kelussia odoratissima (KO) and Angelica sinensis (AS) have been used in their indigenous traditional medicine, for various diseases. This study was conducted to evaluate the volatile oil composition of KO leaves (KVL) and AS root (AVR) and biological activity of essential oils (EOs) and hydroalcoholic extracts of both plants using two different transgenic zebrafish (Danio rerio) models.

Both EOs were isolated by hydrodistillation and analysed by GC and GC/MS. For viability tests, larvae were treated with different concentrations of extracts to determine an appropriate starting concentration. Hydroalcoholic extracts and EOs have been tested in a dose-dependent manner for their biological activity using tissue-specific transgenic zebrafish Tg(fli-1: EGFP) and Tg (ins: GFP-NTR) embryos and larvae. One-way ANOVA was used to compare the mean of pBC area and intersegmental vessels (ISVs) outgrowth between the treatment groups.

Eleven compounds were in common to both oils, comprising 51.3% of KVL and 61.7% of AVR, of which 39.3% in KVL and 37.6% in AVR were phthalide structures. Results revealed that both EOs blocked ISVs formation in the Tg (fli-1: EGFP) embryos increased to 10% of the control value, while both hydroalcoholic extracts did not show any anti-angiogenesis effects in these embryos. In addition, AVR has been shown to significantly induce PBC regeneration following ablation in the Tg (ins: GFP-NTR), but its regenerative activity was lower than that of 5′-N-ethylcarboxamidoadenosine (NECA) as a positive control. Taken together, the anti-angiogenesis activity of both EOs could be attributed to the phthalide structures while for the PBC regenerative activity, other compounds including β-Thujaplicinol, exclusively existing in AVR, might be effective.

Although the genera, organs, and origin of these plants are different, their similar chemical composition and biological activities make them valuable resources for further investigation in basic medical and pharmaceutical science.

Autophagy is a conservative mechanism for cell survival as the main response of cells to stress conditions. The present study aimed to assess the effect of docetaxel on the survival, fertilization, and expression of autophagy-related genes in vitrified oocytes.  The study was conducted in 2018 at the Stem Cells Technology Research Center, Shiraz University of Medical Sciences (Shiraz, Iran). Denuded oocytes were randomly selected and assigned to five groups, namely control (n=133), docetaxel (n=136), docetaxel+cryoprotectants (n=146), docetaxel+vitrification (n=138), and vitrification (n=145). The effect of vitrification on the expression of autophagy-related gene 5 (ATG5) and Beclin-1 was determined using a real-time polymerase chain reaction. Data were analyzed using SPSS software (version 26.0) and GraphPad Prism 9. Survival and fertilization rates in each experimental group were significantly reduced compared to the control group (P=0.001). After in vitro fertilization of oocytes, the 2-cell formation rate was significantly reduced in the docetaxel+vitrification and vitrification groups compared to the control and docetaxel groups (P=0.001 and P=0.001, respectively). Pre-incubation of oocytes with docetaxel reduced gene expression levels of Beclin-1 and ATG5 in the docetaxel+cryoprotectants and docetaxel+vitrification groups (P=0.001 and P=0.019, respectively). The expression level of these genes was also reduced in the docetaxel group compared to the control group (P=0.001).  Incubation of mouse metaphase II oocytes with docetaxel prior to vitrification reduced the expression of autophagy-related genes and increased survival and fertilization rates compared to untreated oocytes.

Efficient production of functional and mature alveolar epithelial is a major challenge for developing any cellreplacement therapy for lung degenerative diseases. The extracellular matrix (ECM) pro-vides a dynamic environmentand mediates cellular responses during development and maintenance of tissue functions. The decellularized ECM(dECM) which retains its native-like structure and bio-chemical composition can provide the induction of embryonicstem cell (ESC) differentiation toward the tissue-specific lineages during in vitro culture. Therefore, the aim of this studywas to evaluate the effect of sheep lung dECM-derived scaffold on differentiation and further maturation of ESC-derivedlung progenitor cells.

This study was an experimental study. In the first step, a sheep lung was decellularizedto achieve dECM scaffolds and hydrogels. Afterwards, the obtained dECM scaffold was evaluated for collagen andglycosaminoglycan contents, DNA quantification, and its ultrastructure. Next, the three experimental groups: i. Sheeplung dECM-derived scaffold, ii. Sheep lung dECM-derived hydrogel, and iii. Fibronectin-coated plates were comparedin their abilities to induce further differentiation of human embryonic stem cells (hESCs)-derived definitive endoderm(DE) into lung progenitor cells. The comparison was evaluated by immuno-staining and real-time polymerase chainreaction (PCR) assessments.

We found that the dECM-derived scaffold preserved its composition and native porous structures whilelacking nuclei and intact cells. All experimental groups displayed lung progenitor cell differen-tiation as revealed by theRNA and protein expression of NKX2.1, P63 and CK5. DE cells differenti-ated on dECM-derived scaffold and dECMderivedhydrogel showed significant upregulation of SOX9 gene expression, a marker of the distal airway epithelium.DE cells differentiated on the dECM-derived scaffold compared to the two other groups, showed enhanced expressionof SFTPC (type 2 alveolar epithelial [AT2] cell marker), FOXJ1 (ciliated cell marker), and MUC5A (secretory cell marker)genes.

Overall, our results suggest that dECM-derived scaffold improves the differentiation of DE cells towardslung alveolar progenitor cells in comparison with dECM-derived hydrogel and fibronectin-coated plates.

Freezing is a long-term egg storage method that plays an important role in assisted reproductive methods. The aim of the present study is to investigate the effect of freezing solutions and docetaxel on the expression changes of autophagy genes such as Atg5 and Beclin-1 in mouse MII oocytes after glass freezing by cryotop method. To achieve this goal, mouse MII oocytes were collected and frozen in two different concentrations of 15% ethylene glycol, 15% dimethyl sulfoxide and 0.5 M sucrose in group A (VS1) and 7.5% ethylene glycol, glycerol. 7.5% and 0.5 M sucrose were frozen in group B (VS2) and some groups were affected by docetaxel before freezing. After thawing, the eggs were fertilized.The percentage of survival and fertilization of frozen and thawed oocytes was evaluated and the expression changes of genes (Atg5 and Beclin-1) were investigated by RT-PCR method. The results showed that there are significant differences between the percentage of survival and the percentage of fertilization in the freezing groups compared to the control group (P<0.05). The percentage of survival and fertilization in the VS1 group decreased compared to the VS2 group. Also, the percentage of survival and conception of the groups pre-incubated with Docetaxel was higher than the non-incubated groups. This study showed that vitrification with cryotop changes the transcript levels of autophagy genes in frozen-thawed MII oocytes, and pre-incubation of oocytes with docetaxel before vitrification can decrease the transcript levels of Atg5 and Beclin-1 in the experimental groups and above Increase the percentage of survival and the percentage of formation of two-celled embryos.

Genome editing is an efficient and accurate method in biological and medical studies. Among the wide range of genome editing techniques, clustered regularly interspaced short palindromic repeats (CRISPR) is one of the simplest and yet promising methods. The CRISPR system consists of two key components; an endonuclease enzyme called Cas9 and guide RNA (gRNA), ensuring that Cas9 enzyme cuts at the right point in the genome. Although CRISPR genome editing is one of the useful methods to modify the genome, there are still multiple challenges in the technique steps.

sgRNAs were designed and ordered accordingly on the basis of the target site and vector of interest. Cloning procedures were performed and confirmed by sequencing as a gold standard. The list of high efficient sgRNAs for the LAMP-2 gene was prepared based on the available outstanding databases by analyzing and comparing the specificity and functionality as two main characteristics.

In this study, we tried to evaluate the main challenges in the process of preparing CRISPR/Cas9 popular vectors (pX330/pX459). A list of high efficient sgRNAs for an autophagy gene is also prepared as an example for clarification of the sgRNA design procedures.

This study tried to depict problems that may be encountered during sgRNA design and plasmid preparation, followed by giving appropriate recommendations.

Isolated pancreatic islets are valuable resources for a wide range of research, including cell replacement studies and cell-based platforms for diabetes drug discovery and disease modeling. Islet isolation is a complex and stepwise procedure aiming to obtain pure, viable, and functional islets for in vitro and in vivo studies. It should be noted that differences in rodent strains, gender, weight, and density gradients may affect the isolated islet’s properties. We evaluated the variables affecting the rat islet isolation procedure to reach the maximum islet yield and functionality, which would be critical for further studies on islet regenerative biology.

The present experimental study compared the yield and purity of isolated islets from nondiabetic rats of two different strains. Next, islet particle number (IPN) and islet equivalent (IEQ) were compared between males and females, and the weight range that yields the highest number of islets was investigated. Moreover, the influence of three different density gradients, namely Histopaque, Pancoll, and Lymphodex, on final isolated islets purity and yield were assessed. Finally, the viability and functionality of isolated islets were measured.

The IEQ, IPN, and purity of isolated islets in 15 Lister hooded rats (LHRs) were significantly (P≤0.05) higher than those of the other strains. Male LHRs resulted in significantly higher IEQ compared to females (P≤0.05). Moreover, IPN and IEQ did not significantly vary among different weight groups. Also, the utilization of Histopaque and Pancoll leads to higher yield and purity. In vivo assessments of the isolated islets presented significantly reduced blood glucose percentage in the transplanted group on days 2-5 following transplantation.

Based on these results, an optimal protocol for isolating high-quality rat islets with a constant yield, purity, and function has been established as an essential platform for developing diabetes research.

Measurement of pancreatic beta cell mass in animal models is a common assay in diabetes researches. Novel whole-organ clearance methods in conjunction with transgenic mouse models hold tremendous promise to improve beta cell mass measurement methods. Here, we proposed a refined method to estimate the beta cell mass using a new transgenic Tg(Pdx1-GFP) mouse model and a recently developed free-of-acrylamide clearing tissue (FACT) protocol.

First, we generated and evaluated a Tg(Pdx1-GFP) transgenic mouse model. Using the FACT protocol in our model, we could quantify the beta cell mass and alloxan-induced beta cell destruction in whole pancreas specimens.

Compiled fluorescent images of pancreas resulted in enhanced beta cell mass characterization in FACT-cleared sections (2928869±120215 AU) compared to No-FACT cleared sections (1292372±325632 AU). Additionally, the total number of detected islets with this method was significantly higher than the other clearance methods (155.7 and 109, respectively). Using this method, we showed green fluorescent protein (GFP) expression confined to beta cells in Tg(Pdx1-GFP) transgenic. This enhanced GFP expression enabled us to accurately measure beta cell loss in a beta cell destruction model. The results suggest that our proposed method can be used as a simple, and rapid assay for beta cell mass measurement in islet biology and diabetes studies.

The Tg(Pdx1-GFP) transgenic mouse in conjunction with the FACT protocol can enhance large-scale screening studies in the field of diabetes.

The aim of the present study was to investigate the effect of docetaxel on the survival rate and in vitro fertilization of oocytes after vitrification by two cryopreservation solution.

For this NMRI mice (8-10 weeks old) were superovulated by injecting PMSG and HCG. Oocytes are surrounded by cumulus and corona cells and must be denuded by 0.1% hyaluronidase enzyme. The oocytes were then divided into 8 experimental groups including control, docetaxel, docetaxel + vitrification 1 solution; docetaxel + vitrification1; vitrification1; docetaxel + vitrification 2 solution; docetaxel + vitrification2; vitrification2. Mature oocytes were vitrified in ethylene glycol and dimethyl sulfoxide solutions at 15% concentration and 0.5 M sucrose in cryopreservation solution1 and ethylene glycol and glycerol at 7.5 concentration and 0.5 M sucrose in cryopreservation solution2. After thawing, their survival and fertilization rates were assessed up to the two-cell stage. Staining of the microtubules in the oocytes was performed with alpha-tubulin antibody.

The results showed a significant difference in survive and fertilization rates compared to the control group (P<0.05). The rate of survival and formation of 2-cell embryos in the first cryopreservation group decreased compared to the second cryopreservation group but the two groups were not statistically significant. The results showed that survival and fertilization rates in pre-incubated groups with docetaxel were higher than non-incubated groups.

Docetaxel could improve reproductive techniques by reducing the damage to the oocyte cytoskeleton.

Pancreatic β cells are recognized as central players in the pathogenesis of types 1 and 2 diabetes. Efficient and robust primary culture methods are required to interrogate β cell biology and screen potential anti-diabetic therapeutics. The aim of this study was to refine monolayer culture of beta cells and to investigate potential inducers of beta cell proliferation.

In this experimental study, we compared different culture methods to optimize conditions required for a monolayer culture of rat pancreatic islet cells in order to facilitate image analysis-based assays. We also used the refined culture method to screen a group of rationally selected candidate small molecules and their combinations to determine their potential proliferative effects on the β cells.

Ham’s F10 medium supplemented with 2% foetal bovine serum (FBS) in the absence of any surface coating provided a superior monolayer β cell culture, while other conditions induced fibroblast-like cell growth or multilayer cell aggregation over two weeks. Evaluation of candidate small molecules showed that a menin inhibitor MI-2 and a combination of transforming growth factor-β (TGF-β) inhibitor SB481542 and protein kinase C (PKC) activator indolactam V (IndV) significantly induced replication of pancreatic β cells.

Overall, our optimized culture condition provided a convenient approach to study the cultured pancreatic islet cells and enabled us to detect the proliferative effect of menin inhibition and combined TGF-β inhibition and PKC activation, which could be considered as potential strategies for inducing β cell proliferation and regeneration.

Skeletal muscle injuries are one of the most common problems in the worldwide which impose a substantial financial burden to the health care system.  Accordingly, it widely accepted that muscle regeneration is a promising approach that can be used to treat muscle injury patients. However, the underlying mechanisms of muscle regeneration have yet to be elucidated. The muscle structure and muscle-related gene expression are highly conserved between human and zebrafish. Therefore, the zebrafish can be considered as an ideal animal model in muscle regeneration studies. In this study, Tol2 transposase was applied to produce Tg(mylpfa: cfp-nfsB) zebrafish model that express a fusion protein composed of cyan fluorescent protein (CFP) and nitrorudactase (NTR) under control of mylpfa promoter. The results showed that MTZ (Metronidazole) treatment of Tg(mylpfa:cfp-nfsB) zebrafish larvae can lead to muscle injury by selective ablation of muscle cells. And also, results confirmed the muscle regeneration ability of the transgenic larvae after withdrawal of Mtz for three days. Overall, The results of this study suggest that the Tg(mylpfa:cfp-nfsB) zebrafish model can be used in muscle regeneration study in order to elucidate the mechanisms of this process.

Diabetes is a major worldwide health problem. It is widely accepted that the beta cell mass decreases in type I diabetes (T1D). Accordingly, beta cell regeneration is a promising approach to increase the beta cell mass in T1D patients. However, the underlying mechanisms of beta cell regeneration have yet to be elucidated. One promising avenue is to create a relevant animal model to explore the underlying molecular and cellular mechanisms of beta cell regeneration. The zebrafish can be considered a model in beta cell regeneration studies because the pancreas structure and gene expression pattern are highly conserved between human and zebrafish.

In this study, the Tol2 transposase was exploited to generate a Tg(Ins:egfp-nfsB) zebrafish model that expressed a fusion protein composed of enhanced green fluorescent protein (EGFP) and nitroreductase (NTR) under control of the Ins promoter.

Metronidazole (MTZ) treatment of Tg(ins:egfp-nfsB) zebrafish larvae led to selective ablation of beta cells. Proof-of-concept evidence for beta cell regeneration in the transgenic larvae was observed two days after withdrawal of MTZ.

This study suggests that the Tg(ins:egfp-nfsB) zebrafish can be used as a disease model to study beta cell regeneration and elucidate underlying mechanisms during the regeneration process.

Growth factors are key elements of embryonic stem cell (ESC) research. Cell line development in eukaryotes is a time-consuming procedure which usually takes 12-18 months. Here, we report an easy and fast method with which production of Chinese hamster ovary (CHO) cells that express and secrete recombinant Activin A, as a major growth factor in endo/mesoderm differentiation of embryonic stem cells is achieved within 3-4 weeks.

In this experimental study, we cloned human Activin A into the pDONR/Zeo gateway entry vector using the BP reaction. Activin A was subcloned next into the pLIX_403 and pLenti6.3/TO/V5-DEST destination vectors by the LR reaction. The result was the production of constructs with which 293T cells were finally transfected for virus production. CHO cells were transduced using viral particles to produce a cell line that secretes the His6- Activin A fusion protein.

We developed a quick protocol which saves up to 3-4 weeks of time for producing recombinant proteins in CHO cells. The recombinant cell line produced 90 mg/L of functional Activin A measured in human ESC line Royan H5 (RH5), during in vitro differentiation into meso-endoderm and definitive endoderm.

Our results showed no significant differences in functionality between commercial Activin A and the one produced using our novel protocol. This approach can be easily used for producing recombinant proteins in CHO.

The ability to generate lung alveolar epithelial type II (ATII) cells from pluripotent stem cells (PSCs) enables the study of lung development, regenerative medicine, and modeling of lung diseases. The establishment of defined, scalable differentiation methods is a step toward this goal. This study intends to investigate the competency of small molecule induced mouse embryonic stem cell-derived definitive endoderm (mESC-DE) cells towards ATII cells.
In this experimental study, we designed a two-step differentiation protocol. mESC line Royan B20 (RB20) was induced to differentiate into DE (6 days) and then into ATII cells (9 days) by using an adherent culture method. To induce differentiation, we treated the mESCs for 6 days in serum-free differentiation (SFD) media and induced them with 200 nM small molecule inducer of definitive endoderm 2 (IDE2). For days 7-15 (9 days) of induction, we treated the resultant DE cells with new differentiation media comprised of 100 ng/ml fibroblast growth factor (FGF2) (group F), 0.5 μg/ml hydrocortisone (group H), and A549 conditioned medium (A549 CM) (group CM) in SFD media. Seven different combinations of factors were tested to assess the efficiencies of these factors to promote differentiation. The expressions of DE- and ATII-specific markers were investigated during each differentiation step.
Although both F and H (alone and in combination) promoted differentiation through ATII-like cells, the highest percentage of surfactant protein C (SP-C) expressing cells (~37%) were produced in DE-like cells treated by Fῠ. Ultrastructural analyses also confirmed the presence of lamellar bodies (LB) in the ATII-like cells.
These results suggest that hydrocortisone can be a promoting factor in alveolar fate differentiation of IDE2- induced mESC-DE cells. These cells have potential for drug screening and cell-replacement therapies.

Type 1 diabetes mellitus (T1DM) is a disease where destruction of the insulin producing pancreatic beta-cells leads to increased blood sugar levels. Both genetic and environmental factors play a part in the development of T1DM. Currently, numerous loci are specified to be the responsible genetic factors for T1DM; however, the mechanisms of only a few of these genes are known. Although several environmental factors are presumed responsible for progression of T1DM, to date, most of their mechanisms remain undiscovered. After several years of hyperglycemia, late onsets of macrovascular (e.g., cardiovascular) and microvascular (e.g., neurological, ophthalmological, and renal) complications may occur. This review and accompanying figures provides an overview of the etiological factors for T1DM, its pathogenesis at the cellular level, and attributed complications.

CRISPR/Cas9 technology provides a powerful tool for targeted modification of genomes. In this system, a donor DNA harboring two flanking homology arms is mostly used for targeted insertion of long exogenous DNA. Here, we introduced an alternative design for the donor DNA by incorporation of a single short homology arm into a circular plasmid.
In this experimental study, single homology arm donor was applied along with a single guide RNA (sgRNA) specific to the homology region, and either Cas9 or its mutant nickase variant (Cas9n). Using Pdx1 gene as the target locus the functionality of this system was evaluated in MIN6 cell line and murine embryonic stem cells (ESCs).
Both wild type Cas9 and Cas9n could conduct the knock-in process with this system. We successfully applied this strategy with Cas9n for generation of Pdx1GFP knock-in mouse ESC lines. Altogether, our results demonstrated that a combination of a single homology arm donor, a single guide RNA and Cas9n is capable of precisely incorporating DNA fragments of multiple kilo base pairs into the targeted genomic locus.
While taking advantage of low off-target mutagenesis of the Cas9n, our new design strategy may facilitate the targeting process. Consequently, this strategy can be applied in knock-in or insertional inactivation studies.

In vitro production of a definitive endoderm (DE) is an important issue in stem cell-related differentiation studies and it can assist with the production of more efficient endoderm derivatives for therapeutic applications. Despite tremendous progress in DE differentiation of human embryonic stem cells (hESCs), researchers have yet to discover universal, efficient and cost-effective protocols. In this experimental study, we have treated hESCs with 200 nM of Stauprimide (Spd) for one day followed by activin A (50 ng/ml; A50) for the next three days (Spd-A50). In the positive control group, hESCs were treated with Wnt3a (25 ng/ml) and activin A (100 ng/ml) for the first day followed by activin A for the next three days (100 ng/ml; W/A100-A100). Gene expression analysis showed up regulation of DE-specific marker genes (SOX17, FOXA2 and CXCR4) comparable to that observed in the positive control group. Expression of the other lineage specific markers did not significantly change (p<0.05). We also obtained the same gene expression results using another hESC line. The use of higher concentrations of Spd (400 and 800 nM) in the Spd-A50 protocol caused an increase in the expression SOX17 as well as a dramatic increase in mortality rate of the hESCs. A lower concentration of activin A (25 ng/ml) was not able to up regulate the DE-specific marker genes. Then, A50 was replaced by inducers of definitive endoderm; IDE1/2 (IDE1 and IDE2), two previously reported small molecule (SM) inducers of DE, in our protocol (Spd-IDE1/2). This replacement resulted in the up regulation of visceral endoderm (VE) marker (SOX7) but not DE-specific markers. Therefore, while the Spd-A50 protocol led to DE production, we have shown that IDE1/2 could not fully replace activin A in DE induction of hESCs. These findings can assist with the design of more efficient chemically-defined protocols for DE induction of hESCs and lead to a better understanding of the different signaling networks that are involved in DE differentiation of hESCs.