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Although exercise is known as an effective factor in maintaining and improving bone strength; it is not clear that its effects on bone-forming and bone-eating cells of different age groups are the same. Therefore, this study aimed to investigate the effect of resistance-endurance training on the number of osteocyte, osteoblast, and osteoclast cells in femur bone tissue in male rats of different ages.

In the present study, 30 male Wistar rats in three age groups of 2 weeks, 6 weeks, and 96 weeks were randomly divided into 2 groups of 5 each, training and control. Resistance-endurance exercises were performed for 6 training sessions per week for 6 weeks. Rats were sacrificed under carbon dioxide gas. H&E staining was used for tissue microscopic examination.

The results of one-way analysis of variance with Tukey's post hoc test showed that higher amounts of osteoblast and osteocyte cells and lower amounts of osteoclast cells in trained rats of all three age groups were significant compared to their control group. The comparison of exercise groups showed that the number of osteoblasts in the child and adult groups, the number of osteocytes in the adult group, and the number of osteoclasts in the adult and elderly groups were higher.

The results showed that resistance-endurance training led to an increase in bone-forming cells and a decrease in bone-eating cells. However, the effects of exercise on bone formation in younger age groups were more than in old age. Nevertheless, the prevention of exercise from the process of bone loss in older age, especially old age, was evident.

Evaluation of the alkaline phosphatase expression is known as one of the diagnostic markers to confirm the stem cells differentiation into osteoblasts. Several methods, including immunocytochemistry, are used to measure alkaline phosphatase in different studies. Due to limitations of using this method, we decided to optimize the calorimetric method as an alternative, low cost and efficient method for quantitative assessment of alkaline phosphatase.

Mesenchymal stem cells derived from human adipose tissue were used. Cells were differentiated into osteoblasts using an induction medium. Alkaline phosphatase levels were assessed on the days 0 and 21 of differentiation using both immunocytochemistry and calorimetric methods.

Immunocytochemistry findings demonstrated a significant increase (approximately 5-fold) in alkaline phosphatase expression level on the 21st day of differentiation compared to that on the day 0 (p <0.0001). Also, statistical analysis of the results of the calorimetric test showed a significant increase (approximately 9-fold) in alkaline phosphatase expression level on the 21st day of differentiation compared to  that on the day 0 (p<0.0001).

Comparison of the data between calorimetric and immunocytochemistry showed similar results. These findings suggested that colorimetric assay can be used as an alternative, quantitative, fast, and low cost method for determining the levels of alkaline phosphatase in osteoblasts differentiated from mesenchymal stem cells.

In tissue engineering, a porous material is applied as the extracellular matrix or scaffold for cell growth. Then growth factors are added to this scaffold whose cytotoxicity must be assessed. In this study, the cytotoxicity effects of polyhydroxybutyrate/chitosan/bioglass nanocomposite scaffolds on human osteoblast-like cells (SAOS-2 cells) are explored.

This study was experimental and was done in Isfahan Dental School. The polyhydroxybutyrate/chitosan/bioglass nanocomposite scaffold was fabricated using the electrospinning method. Scanning Electron Microscopy (SEM) analysis was used to evaluate the morphological characteristics of the nanofibers and their diameter distribution. Additionally, bioglass nanoparticles in the fibers were identified via SEM. The MTT assay was performed to assess cell viability after 3, 5, and 7 days. The collected data were analyzed using SPSS 20.0 through statistical tests including Kruskal-Wallis test (p value ≤ 0.05).

According to SEM images, the scaffold fibers were fully porous and no beads were observed. Furthermore, the polyhydroxybutyrate/chitosan/bioglass scaffold showed greater cell viability and proliferation compared to the groups lacking bioglass.

The polyhydroxybutyrate/chitosan/bioglass scaffold has no cytotoxic effect on osteoblast– like cells.

Control processes in osteoblastic differentiation of mesenchymal stem cells are not yet fully understood. Epigenetic mechanisms, especially the methylation of CpG Islands in the promoter of genes, are considered as one of the most important control mechanisms in stem cell differentiation. In the process of differentiation, it is debated whether only the methylation of specific genes changes or the methylation of global DNA. Therefore, in the present study, the state of global DNA methylation was evaluated during osteoblastic differentiation of mesenchymal stem cells by differentiation medium and also in treatment by zoledronic acid.

In this laboratory study, after isolation and proliferation of mesenchymal stem cells, induction of osteoblastic differentiation was done using differentiating medium and zoledronic acid. DNA extraction was performed at differentiation weeks 1, 2, and 3 as well as from undifferentiated mesenchymal stem cells. Global DNA methylation status was assessed by antibodies against 5-methyl cytosine. Repeated measurement design test was used to analyze the data.

Global DNA methylation status of the genome did not change during osteoblastic differentiation of mesenchymal stem cells (p=0.093). Also, treatment with zoledronic acid had no effect on global DNA methylation (p=0.057).

Osteoblastic differentiation of mesenchymal stem cells by differentiation medium and also in treatment with zoledronic acid is not associated with altered global methylation of the genome. Therefore, the differentiation process of mesenchymal stem cells to osteoblasts is a unique pathway, and possibly other genetic and epigenetic mechanisms play a role in controlling it.

One of the tissues that is affected by physical activity is bone. Bone is one of the tissues that needs to receive mechanical load to have normal function as a key factor in strengthening bone mass (2). Evidence shows that the mechanical load resulting from physical activity activates a set of proteins involved in the process of osteoblast activation and inhibits osteoclasts. One of these proteins is osteonectin. It is commonly used as a serum marker of osteoblastic bone formation and is believed to regulate minerals in the bone matrix, but now new genetic and pharmacological evidence also points to the hormonal role of this protein (5).Osteopointin, on the other hand, accounts for about 2% of non-collagenous bone proteins and is synthesized mainly by osteoblasts as well as bone-forming cells, bone cells and other hematopoietic cells in the bone marrow (7). Another important factor in the ossification process is ALP, a membrane-bound tetrameric enzyme found in the plasma membrane of osteoblasts. This substance plays an important role in the formation of osteoids and mineralization by degrading enzymes inhibiting minerals, pyrophosphate at alkaline pH (8).Also, due to their active phytochemical compounds, medicinal plants can affect the formation and destruction of bone tissue through various mechanisms. One of the plants used in traditional medicine for various therapeutic purposes is palm tree pollen. This plant is used to improve infertility and impotence in men and women. Phytochemical compounds such as estrone, α-amirin, triterpenoidal, saponins, flavonoids, estrone, estradiol and estriol are abundant in this plant (15). Therefore, the researcher seeks to answer the question whether resistance training and date pollen extract affect bone tissue density and osteoblast cell proliferation in young males?

For the present experimental study, 36 8-week-old male rats with a weight range of 220 20 20 g were purchased from the Pasteur Institute of Iran and randomly divided into 6 groups: 1) sham, 2) exercise, 3) palm pollen, 4) testosterone. 5) Exercise + palm pollen and 6) Exercise + Testosterone were divided. After one week of adaptation, groups 2, 4 and 6 performed resistance training for four weeks and five sessions per week. Groups 3 and 5 performed 100 mg / kg of date fertilization pollen five days a week. Gavage was also given. Groups 4 and 6 also received 2 mg / kg of testosterone propionate per week peritoneally. Finally, descriptive statistics, Shapiro-Wilk test, two-way analysis of variance and Benferroni post hoc using SPSS software at a significance level of p <0.05 were used for statistical analysis of data.

The results showed that resistance training and drug administration significantly increased osteocalcin gene expression, ALP concentration, ALP gene expression and osteopontin and osteogenesis of femoral bone tissue. Although the highest expression of osteocalcin gene was observed in the group of resistance training and date palm pollen or testosterone enanthate, but the interaction of these two interventions was not statistically significant. It was also found that resistance training (palm pollen and testosterone enanthate) significantly reduced serum ALP. The interaction of these two interventions on serum ALP concentration was significant. Simultaneous resistance training and medication enhanced the reducing effect of each intervention.

In this study, due to resistance training, osteocalcin, osteopontin, ALP, RUNX2 gene expression, ALP protein expression and osteogenesis were significantly increased. While serum ALP showed a significant decrease.The expression of bone matrix proteins, alkaline phosphatase, and osteocalcin appears to increase with the differentiation of osteoblasts, which may lead to bone mineralization and formation. Another reason for the increased expression of acetocalcin gene in this study can be explained by the change in cytokine changes caused by resistance training, especially interleukin-6. Much of IL-6 has been reported to be secreted into the bloodstream from muscle during physical activity, an increase that is essential for increasing physical function capacity. IL-6, on the other hand, triggers signals in osteoblasts to stimulate osteoclast differentiation and the secretion of the bioactive form of osteocalcin into the bloodstream. In general, an increase in interleukin-6 is necessary to increase circulating osteocalcin levels during physical activity (28).Another mechanism of increased expression of osteocalcin gene induced by resistance training in this study can be explained based on the effect of resistance training on oxidative stress. Evidence suggests that regular resistance training can increase antioxidant capacity and reduce oxidative stress (29). On the other hand, increasing oxidative pressure can reduce the process of osteoblast differentiation by activating apoptotic processes in bone (30).In the present study, resistance training increased the expression of osteopontin gene. Along with osteocalcin, acetaminophen is involved in the organization of the extracellular matrix, the coordination of bone cell interactions with the extracellular matrix, and the matrix minerals. Both proteins also play a structural role in bone and determine the tendency of bone to break. As a result, these proteins may regulate the structure and morphology of the entire bone and affect the mechanical properties of bone (36, 37). Like osteocalcin, the mechanical load resulting from resistance training appears to stimulate the expression of the osteopontin gene. It has been shown that the application of mechanical load on bone increases the periosteal of bone by increasing the activation of bone formation processes. In these conditions, mechanical load can stimulate both gene expression and ALP protein expression by activating adult osteoblasts and increase They become (26).On the other hand, date palm extract could increase the expression of the studied genes and the process of osteogenesis. The effect of date palm extract on increasing gene expression of osteocalcin, osteopontin, alkaline phosphatase and osteogenesis can be examined from two perspectives. The first view is the effect of this extract on the motility of LH followed by stimulation of testicular Leydig cells to produce and secrete circulating testosterone. Numerous studies have reported stimulation of testosterone secretion after induction of date palm pollen (45, 46).The view on the effect of date pollen extract on the process of outcomes measured in this study is the antioxidant and anti-inflammatory role of the compounds in this plant material (47, 48). As mentioned about the antioxidant and anti-inflammatory effect of physical exercise and its role on acetoblasts, increasing oxidative stress and inflammation has an inhibitory effect on the differentiation and proliferation of osteoblasts (30). Induction of date palm pollen extract in this way can develop the process of bone formation.

Mesenchymal stem cells are able to differentiate into osteoblasts, which is forced by several growth factors. Similar to growth factors, plant metabolites have been shown to be able to support stem cell differentiation. The aim of this study was to assess the synergistic effects of resveratrol-poly(lactic-co-glycolic acid) (PLGA) and curcumin-PLGA nanoparticles on directing adipose-derived mesenchymal stem cells towards osteoblastic differentiation.

Human mesenchymal stem cells derived from the adipose tissue, after being characterized by flow cytometry, were simultaneously treated with 10 μM concentrations of each of PLGA-resveratrol and PLGA-curcumin nanoparticles. The cytotoxic effects of resveratrol and curcumin were evaluated by the MTT assay, and their differentiating potentials were evaluated by Alizarin red staining.

According to MTT results, neither resveratrol-PLGA nor curcumin-PLGA nanoparticles had no significant toxic effects on the target cells after 24 hours. At the 20 and 10 μM concentrations of resveratrol-PLGA and curcumin-PLGA nanoparticles, respectively, a significant increase was observed in the proliferation of human mesenchymal stem cells. Alizarin red staining showed that treatment with resveratrol-PLGA and curcumin-PLGA nanoparticles increased the deposition of mineral ions in the extracellular matrix, an indicator of the onset of the cellular differentiation process.

The results of this study showed that the simultaneous use of bioactive compounds such as resveratrol-PLGA and curcumin-PLGA nanoparticles can direct stem cells towards osteoblastic differentiation. The simultaneous use of resveratrol-PLGA and curcumin-PLGA nanoparticles increases their efficiency at lower concentrations due to their synergistic effects.

Spinal cord injury (SCI) causes devastating injuries in patients. The main mechanisms of the pathogenesis of secondary injury include nerve degeneration, gliosis, and inflammation. Spinal cord injury induces a disorder or failure in several organs due to the vital role of the spinal cord in regulating bodily functions. Osteoporosis is a consequence of spinal cord injury that occurs in the vast majority of patients with spinal cord injury.
Articles on the related topic were searched in the following databases: Science Direct, Scopus, Springer Science, PubMed and Google scholar to have been used in writing from this review article. A total of 120 related research papers, including quantitatve and qualitative researches in English, from the last 57 years papers (1962- 2019) were included in this study. The review article is written according to 120 articles and the keywords “Spinal cord injury, Osteoporosis, Inflammation, Osteoblast and Osteoclast”.

Although weight loss is an important factor in the development of osteoporosis following SCI, inflammation, nerve damage, and hormonal changes also contribute to this process. Hormonal changes mediated by SCI may contribute to postoperative osteoporosis with several mechanisms. These mechanisms included: increased renal excretion and decreased intestinal absorption of calcium, consequently, a negative balance of calcium ions; Vitamin D deficiency; impair the function of the gonads and inhibits the osteoanabolic (ossification) activity of sex steroids; elevated blood leptin; Pituitary suppression of parathyroid hormone, and bone loss following SCI may (at least in part) be caused directly by insulin resistance and insulin-like growth factor.

It has been shown that growth factors have a great role in improving wound healing processes. In addition, a relatively high proportion of endodontically treated teeth will require retrograde treatment in the future. Therefore, the aim of the present study was to evaluate the effect of platelet-rich plasma (PRP) on differentiation of osteoblasts and osteoclasts in the presence of a three-dimensional scaffold.

In this in vitro study, mesenchymal stem cells were isolated from the Wharton jelly of human fetal umbilical cord and assigned into osteoblasts and osteoclasts groups for the evaluation of differentiation. Each group was subdivided into two subgroups with and without PRP. All the samples were cultured on two PCL/HA (polycaprolacton/hydroxyapatite) polymer scaffold. To evaluate differentiation into osteoblasts, DMEM (Dulbecco’s Modified Eagle’s Medium) was used that contained 7‒10-mol dexamethasone, 10-mol glycerophosphate, and 50-mol ascorbic acid. In the osteoclast differentiation group, RANKL (receptor activator of nuclear factor Kappa-B ligand) and CSF (colony-stimulating factor) were used. In addition to differentiation agents, 10% PRP was added to the two subgroups containing PRP. After 10 days, differentiation into osteoblasts and osteoclasts was evaluated by assessing the expression of specific genes using real-time PCR. In the osteoblast differentiation group, expression of osteocalcin and osteotrix genes was evaluated and in the osteoclast differentiation group, expression of TRAP (tartrate-resistant acid phosphatase) was evaluated. Data were analyzed using one-way ANOVA, two-way ANOVA, and post hoc Tukey tests, using Graph Pad software program.

Evaluation of the expression of the TRAP gene did not reveal any significant differences between the study and control groups. There was a significant difference between the group with the osteoclastogenic factor alone and the group with osteoclastogenic factor and PRP (p=0.0324). There was a significant difference in osterix expression between the control group and the PRP-treated group (p=0.0050). There was a significant difference between the group with osteoblastogenic factor alone and the group with osteoblastogenic factor and PRP (p=0.00001). There was a significant difference in the expression of osteocalcin gene between the control and PRP-treated groups (p=0.0110); however, the differences between the osteoblastogenesis groups with and without PRP treatment were not significant (P=0.5191). The differences in the expression of TRAP, osterix, and osteocalcin genes between the control and PRP-treated groups were significant (p=0.006 and p=0.0001, respectively).

The results of the present study showed that PRP resulted in an increase in osteoblastic differentiation, with no significant increase in osteoclastic differentiation.

The resin secretions of Cannabis sativa are called Hashish, which has medicinal and psychological properties. The most important psychoactive compound of this plant is THC (Delta-9-Tetrahydrocannabinol), which can stimulate cannabinoid receptors in the body. This study was carried out to evaluate the effect of hydroalcoholic extract of Cannabis sativa on cell survival and osteoblastic differentiation of human mesenchymal stem cells. In this experimental study, mesenchymal stem cells derived from fat tissue of human abdominal were treated with 100 ng/ml concentration of hydroalcoholic extract of Cannabis sativa. Flow cytometry and RT-PCR techniques were used for detection of cells. The cytotoxic effect of Cannabis sativa extract and osteoblastic differentiation of cells were investigated using MTT method and Alizarin-Red staining, respectively. The karyotype analysis was performed with the preparation of extended metaphase chromosomes. The identity of the fat mesenchymal stem cells was confirmed by the expression of non-hematopoietic mesenchymal markers (CD90, CD44 and CD73) and the lack of expression of the hematopoietic marker (CD34 and CD45). The Alizarin-Red showed that the treatment with Cannabis sativa has no effect on the osteoblastic differentiation of human fat mesenchymal stem cells, and the treated cells were differentiated into bone cells same as control group. Also, Cannabis sativa extract has no effect on the structure, morphological status and number of chromosomes of these cells. This study showed that human fat mesenchymal cells in the presence of a hydroalcoholic extract of Cannabis sativa maintain the ability of osteoblastic differentiation. Also, this extract has no effect on the chromosomal karyotype of the cells.

Mesenchymal stromal cells (MSCs) are stem cells with high differentiation potential that have been investigated for bone differentiation both in vivo and in vitro during the last decade. It was shown that platelet-rich plasma (PRP) can accelerate bone formation. Due to limitation of human studies in this field, and unknown appropriate concentration of platelet-rich plasma, this study compared the effect of applicable concentration of platelet-rich plasma on osteoblast differentiation in mesenchymal stromal cells.
Mesenchymal stromal cells were isolated from human adipose tissue and differentiated into osteoblasts. The effects of 10% and 15% of platelet-rich plasma on bone differentiation evaluate via measuring biochemical markers like alkaline phosphatase activity and calcium deposition. The expression of RUNX2 and osteocalcin genes were calculated using real-time polymerase chain reaction.
Findings: Compared to other groups, when treated by 10% platelet-rich plasma, human adipose-derived cells, having the potential to differentiate to adipocyte and osteoblast cell lines, showed significant increase in osteoblast differentiation rate, expression of gene markers, enzyme activity, and mineralization.
Activated platelet-rich plasma as a biological catalyst has different and significant effect on bone differentiation of human mesenchymal stromal cells (hMSCs) in different concentration; so, the onset of osteogenic differentiation in 10% platelet-rich plasma was observed earlier than other groups. Further investigations in this field can improve its clinical application in bone remodeling.

Background and Osteoporosis is a common disease characterized by low bone mass that can harm health. Lactoferrin increase osteogenesis. PerFlourooctyl Bromide is a neutral particle that used as a drug carier.
In this study, lactoferrin (LF) of Camel milk were isolated. PFOB-NEP was prepared using an oil-in-water emulsion method (O/W). and then evaluated by The zeta potential measurement methods and tryptophan fluorescence spectroscopy before and after loaded by lactoferrin. The concentrations of 25, 50 and 100 µg/mL of LF were loaded on perflourooctylbromide -NEPs. The effects of standard LF, the LF, and LF loaded on PFOB-NEPs on growth of osteoblasts Cell Line (MG-63) was studied using MTT assay.
The results showed that the LF and the LF loaded on PFOB-NEPs significantly increased Osteoblast cells proliferation. But there was no significant difference between the LF and LF uploaded on PFOB-NEPs (α The results proved that LF of camel milk causes the growth of osteoblasts cells in MG-63 cell lines. It is also possible to load LF on PFOB-NEPs and this nanoparticle could be used as carriers of lactoferrin.

Following initial studies reporting the presence of βeta adrenergic receptors on bone cells, several studies have investigated the role of the Beta adrenergic system in the formation and resorption of bone. The goal of this report was to review the data supporting the role of the beta adrenergic system and osteo-neuromediators in the regulation of bone homeostasis.
In this review, more than 100 published articles were reviewed for the evidence of the adrenergic effect on bone remodeling and focused on the latest advances in this area.
Based on a variety of pharmacologic, genetic and clinical studies focused on b-adrenergic receptor (bAR) signaling in bone cells, The adrenergic activity of the sympathetic nervous system has been shown to be a negative regulator of bone mass; adrenergic signaling inhibits osteoblast proliferation and promotes osteoclastogenesis .
Altogether, these observations and linked findings are of great significance since they improve our understanding of bone physiology., and uncovered new potential therapeutic strategies for the design of bone anabolic drugs. Certainly, knowledge about downstream factors of beta-adrenergic system can be helpful in making decisions about appropriate therapeutic interventions.

Saffron (Crocus Sativus L) has various pharmacological effects. Gold nanoparticle (GNPs) is involved in cell function and differentiation. In this study the osteogenic effects of Saffron extract and biogenic synthesis gold nanoparticles (GNPs) using Shirazi Thyme (Zataria multiflora) leaves was investigated on differentiation of bone marrow mesenchymal stem cells (BMSCs). In this exoerimental study, Wistar rat bone marrow cells were collected and identified. Then these cells were detected by flow cytometry.Cytotoxicity of GNPs and Saffron extract was measured by MTT assay(. Samples were divided to 3 experimental groups and were treated with GNPs (20 µg/ml), Saffron extract (400 µg/ml), and a combination of Saffron extract and GNPs (400 and 20 µg/ml respectively). Differentiation effects were investigated by alizarin red staining after 21 days and alkaline phosphates (ALP) activity after 14 days. Flow cytometry analysis of surface specific marker confirmed the presence of stem cells. According to the results of MTT assay (P<0.05), the concentrations chosen for combination had not affect cell viability. Alizarin red staining showed Saffron extract and GNPs alone increased osteogenic differentiation. This effect on synergic group was higher. Alkaline phosphates activity in the combined Saffron and GNPs group showed a significant increase compared to the other groups. According to the findings of this study, synergic used of Saffron extract and GNPs effectively enhance BMSCs differentiation.

Green tea is a rich source of Epigallocatechingallate and has many antioxidant properties that can increase bone mineral content. On the other hand, people in current industrialized societies are in direct contact with contaminants such as bisphenol A that, in addition to causing environmental problems, are harmful to human�s health. In this study, following extraction and cultivation of rat bone marrow mesenchymal stem cells, third passage cells were divided into 13 groups, control, different doses of bisphenol A (250 and 1000 nM) and different doses of Epigallocatechingallate (5, 10, 15, 20 and 30 M) + bisphenol A, and were treated in an osteogenic environment for 21 days. Afterward, viability and mineralization of bone matrix were assessed. To continue the study, 250 nM dose ofbisphenol A and 30 M dose of Epigallocatchingallate were selected. Simultaneous effect of bisphenol A and Epigallocatchingallate on osteogenic differentiation of cells through MTT tests, alizarin red, evaluation of intracellular and extracellular calcium deposition content, alkaline phosphatase enzyme activity and morphology of differentiated cells was analyzed by florescent colors. Based on two-way ANOVA, 250 and 1000 nM doses of bisphenol A caused a highly significant reduction in the viability of bone marrow mesenchymal stem cells (P<0.05). Moreover, Epigallocatchingallate (30 M) was able to reduce the destructive effect of bisphenol A on bone marrow stem cells. The present study showed that Epigallocatechingallat can compensate for the destructive effects of bisphenol A on mesenchymal cells.

Saffron has the various significant pharmacological effects.Vitamin D3 is also involved in differentiation and functions in various cells. This study aimed to investigate the synergetic effects of the aqueous extract of saffron and vitamin D3 on the differentiation of mesenchymal stem cells into osteoblasts. Flushing method was used to extract mesenchymal stem cells. Immunocytochemistry agonist CD44 antigen was also used to verify the identification of stem cells. In the experimental group, cells were treated with 600,700,800 mg/l doses of the saffron extract and the above-mentioned doses of saffron with 5×10-7 M of vitamin D3 were used to induce differentiation. The control group did not receive any treatment. Cell differentiation was evaluated by the alkaline phosphatase activity assay after 10 days and Alizarin Red staining was also performed 21 days after the treatment. Alkaline phosphatase activity in the vitamin D3 and saffron groups showed a significant increase compared to the control groups. The activity of this enzyme in the combined treatment groups showed a significant increase compared to their single use. The Alizarin Red staining showed the differentiative effects of vitamin D3, saffron and their coadministration in the differentiation of stem cells into osteoblast.The saffron and Vitamin D3 coadministration has the most profound effect on the differentiation of mesenchymal stem cell into osteoblast. The results indicate that the coadministration of saffron and vitamin D3 has a significant effect on the differentiation of mesenchymal stem cell into osteoblast cells.

Stigmas of Crocus sativus L. is widely used against different human diseases.Regarding the properties of this plant, in the present study the effects of saffron extract on inducing cell differentiation of a rat's bone marrow-derived mesenchymal stem cells (MSCs) into osteoblasts was examined. Bone marrow cells collected from ……..Wistar rat's femor and flowcytometrywere used to identify them. In the experimental group (n=…..) MSCs treatment was done with various concentrations of saffron extract (i.e.0.5, 1, 1.5, and 2 mg/ml). Cytotoxic effect of saffron extract was evaluated using MTT assay and its aqueous extract effect on cell differentiation was investigated by means of Alizarin staining and alkaline phosphates activity. Flowcytometry results confirmed the presence of stem cells using CD44 antibody. MTT assay results showed that the extract concentration of 1.5 mg/ml resulted in the death of 50 percent of stem cells derived from therats’ bone marrow during 24 hours (P<0.001). Alizarin staining showed saffron aqueous extract increased osteogenic s cell differentiation in a dose dependent manner in 21 days. (The maximum cell differentiation achieved by700 μg/ml concentration). Besides, higher alkaline phosphates activity was evident in the experimental group compared to the control group (n=……) in the 14th day (P<0.001). According to the findings of the current study, MSCs derived from the rat's bone marrow transform into osteoblasts when treated with saffron aqueous extract.

Bone defects in jaws create major problems for oral and maxillofacial surgery. To overcome the limitations of Autografts tissue engineering uses autogenus cells and synthetic scaffolds. Type of cells or cell sources have an important effect on the construction which is produced. The aim of this study was to evaluate the feasibility and probable limitations of osteoblast isolation from the periosteum and alveolar bone in an animal model and to compare their probable results quantitatively. Bone and periosteal samples were harvested from interdental septum and retromolar area of 4 dogs. Because no cell was grown new samples were harvested from edentulous ridge and buccal mandibular periosteum. Since no cell was isolated in next step samples were harvested from buccal area of maxillary premolars and explants in cell culture medium. After 2 weeks adherent cells reaching 80% confluent; cells were counted and passaged in cell culture flasks. Despite first good proliferation of periosteal cells of all dogs in P0, their growth was stopped and they become senescence after one week. The key problems in culture techniques are cell senescence and de-differentiation leading to lose the ability of proliferation. It seems there are probable reasons for isolating of osteoblasts including thermal damage of cells, contamination of culture with fibroblasts, inconsistency of medium and cell requirements, enzymatic damage from enzymes used for cell passage and high donor ages.

Tissue engineering using somatic cells and synthetic extracellular matrix (scaffold) represents a new approach for regeneration of mineralized tissue and bone. This study was carried out to investigate the ability of a PLLA/HA scaffold to culture osteoblast cells in a three dimensional milieu. Three bony samples were taken from extraction sites during surgical extraction of wisdom teeth. Osteoblasts were obtained from specimens by using trypsin and collagenase and were cultured in monolayer up to passage four. Cells were seeded on PLLA/HA scaffolds at density of 106 cells/ml and then incubated for 21 days. The seeded cells were evaluated by Hoechst، von kossa and H&E stainings and scanning electron microscopy. Cellular growth was more pronounced when isolation was carried out by collagenase. According to scanning electron microscopy، osteoblast cells had been proliferated and attached to the scaffolds. H&E، Hoechst and von kossa stainings confirmed the presence of the harvested cells in the scaffold too. Our findings suggest that osteoblast cells can grow onto PLLA/HA scaffold in vitro.

Bone is a tissue with high repair capacity; but، this ability dramatically is limited during irrecoverable bone and skeletal defects. Stem cell therapy is a promising approach for construction of bone tissue. Mesenchymal stem cells (MSCs) have been introduced as basic tools for bone tissue generation in tissue engineering. Core binding factor alpha 1 (Cbfa1) is one of the main genes involved in osteogenesis. Since relative expression of Cbfa1 in differentiated osteoblasts from adipose derived stem cells is unknown، this study aimed to evaluate the gene expression pattern of Cbfa1 in adipose derived differentiated osteoblasts in 4 different time intervals.

Real-time PCR was used for studying the gene expression of Cbfa1 in human normal osteoblasts and adipose derived osteogenic osteoblasts at the days 7، 14، 21 and 28.

There was a progressive increase in Cbfa1 expression over the differentiation period of adipose derived mesenchymal stem cells (ADSCs) from day 7 to day 28. Differentiated osteoblasts expressed Cbfa1 lower than native osteoblasts (P < 0. 05).

ADSCs are an attractive source for engineering a new bone tissue. According to our results، adipose derived differentiated osteoblasts express candidate gene at least on day 7 of culture. Our study indicates that longer treatment of ADSCs in osteogenic medium confer better osteoblastic properties to these cells.

In recent years, composite scaffolds made ofpolymers and bioactive ceramics have foundnumerous applications in bone tissue engineering dueto their superior properties. Among various polymers, chitosan (Cs) and gelatin (Gel) gained more attention because of their desirable properties. In this study, by using these two polymers and hydroxyapatite (HA) which resembles inorganic phase of human bone, three-dimensional composite scaffolds were preparedby freeze-drying method andbehavior of osteoblast cells on them was evaluated.Thisstudy aimed at preparing an appropriate bioactive scaffold for bone tissue engineering.

In order to evaluatethe effect ofgelatin concentration onbiological propertiesof scaffolds, three different concentrations of gelatin (0,10, and 20%) were added to composite scaffolds.Forassessment of thebiological properties of scaffolds, osteoblast cells were cultured on the composite scaffolds and their behavior was monitored.Scanning electron microscopy (SEM)analysis and alkaline phosphatase activity (ALP)testwerecarried out to assess the mentioned factors.

SEM analysis showed high cell attachment and proliferation on the scaffolds. Alkaline phosphatase activity of osteoblast cells indicated the suitability of composite scaffolds containing a higher concentration of gelatincompared to otherconcentrationsas well as overallhigh activity of osteoblast cells on all scaffolds.

Cs/Gel/HA bioactive composite scaffold is recommended for bone tissue regeneration purposes as a suitable scaffold.