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1.
Arch Iran Med ; 22(6): 318-327, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31356098

RESUMO

BACKGROUND: Accomplishments in stem cell science and tissue engineering have resulted in a remarkable revolution in the context of future medicine. However, a general insight over the progress of stem cell research in Iran is still lacking. A better understanding of current needs in this field is required to design a better national roadmap. METHODS: In this study, we defined the geographical regions based on the significance of their contribution to stem cell research; then, using the Scopus database, we retrieved reports from Iran and other countries concerning stem cell science and regenerative medicine published from 1994 until the end of 2016. RESULTS: A significant number of citations belong to North America (6554029 citations equal to 49% of the total citations) and Europe (4425465 citations equal to 33% of the total citations) and the rest of citations were related to Asia (2423352 citations equal to 18% of the total citations). East Asian (2168472 citations equal to 76% of the total citations related to Asia) documents were cited more than those from the Middle East (ME) (494141 citations equal to 17% of the total citations related to Asia) and North and Central Asia (196382 citations equal to 7% of the total citations related to Asia). Iran as a country in the ME attracted 17% of the total citations related to the Asian countries winning the second position in this regard. The overview of total number of citations showed a sharp increase and upward trend in citation numbers for all the Iranian institutes from 2007 that resulted in the expansion of stem cell science in all major cities of Iran such as Shiraz (8%), Mashhad (5%), Isfahan (5%) and Ahvaz (5%). H-index of Tehran University of Medical Science, which has the highest total citations and document numbers, is the highest among all Iranian research institutes. Citation per paper of Royan Institute (RI) is the highest among the top 10 Iranian institutes, by 13 citations per paper. CONCLUSION: Stem cell research in Iran is rapidly developing. Since 2007, the number of published documents in major research institutes increased; thus, there is necessity for analysis of the status of publications in this field and choosing a better direction based on needs. Furthermore, it is necessary to expand and organize international collaborations to enrich our research and benefit from different team experiences.

2.
Differentiation ; 109: 1-8, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31323479

RESUMO

End-stage renal disease (ESRD) is a major global public health issue. In the past decade, regenerative medicine and cell-based therapies were recommended for treatment of devastating diseases like ESRD. Renal progenitor (RP) cells are essential players in such treatment approaches. The major practical difficulties in application of RP cells are generation of these cells and preservation of their self-renewal capacity; also, they should lack identified appropriate cell surface markers. To identify and isolate RP cells, two cell surface markers namely, CD133 and CD24 were recently used. In this study, we used these markers to facilitate selection and purification of RP cells from embryoid bodies (EBs), and assessed the impact of the use of bFGF on frequency of CD133+CD24+ expression in cells presented in EBs. Moreover, following isolation of CD133+CD24+ cells from EBs, we evaluated the effect of embryonic, neonatal and adult mouse kidney-derived mesenchymal stem cells (E-KMSC, N-KMSC and A-KMSC respectively) and fibronectin on further differentiation of the sorted cells. Hence, we cultured undifferentiated human embryonic stem cells (hESCs) in suspension state in the presence or absence of bFGF and determined maximum number of CD133+CD24+ cells in bFGF-treated EBs on day 7. Then, we tested the effect of E-KMSC co-culture and seeding on fibronectin-coated plated on differentiation of the sorted cells into renal epithelial cells. Results revealed down-regulation of several RP cells, markers in CD133+CD24+ cells. In contrast, renal epithelial marker gene expressions were up-regulated after 7 days of co-culture with E-KMSC. Furthermore, fibronectin resulted in higher expression of renal epithelial markers compared to the E-KMSC co-cultured cells. All in all, bFGF could enhance the number of RP cells expressing CD133 and CD24 markers, in human EBs. We suggest E-KMSC and fibronectin as a promising supplementary factor to further induce differentiation of RP cells into renal epithelial cells.

3.
Oncogene ; 38(34): 6226-6239, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31308488

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) arises through accumulation of multiple genetic alterations. However, cancer cells also acquire and depend on cancer-specific epigenetic changes. To conclusively demonstrate the crucial relevance of the epigenetic programme for the tumourigenicity of the cancer cells, we used cellular reprogramming technology to reverse these epigenetic changes. We reprogrammed human PDAC cultures using three different techniques - (1) lentivirally via induction of Yamanaka Factors (OSKM), (2) the pluripotency-associated gene OCT4 and the microRNA mir-302, or (3) using episomal vectors as a safer alternative without genomic integration. We found that induction with episomal vectors was the most efficient method to reprogram primary human PDAC cultures as well as primary human fibroblasts that served as positive controls. Successful reprogramming was evidenced by immunostaining, alkaline phosphatase staining, and real-time PCR. Intriguingly, reprogramming of primary human PDAC cultures drastically reduced their in vivo tumourigenicity, which appeared to be driven by the cells' enhanced differentiation and loss of stemness upon transplantation. Our study demonstrates that reprogrammed primary PDAC cultures are functionally distinct from parental PDAC cells resulting in drastically reduced tumourigenicity in vitro and in vivo. Thus, epigenetic alterations account at least in part for the tumourigenicity and aggressiveness of pancreatic cancer, supporting the notion that epigenetic modulators could be a suitable approach to improve the dismal outcome of patients with pancreatic cancer.

4.
Trends Biotechnol ; 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31227305

RESUMO

The human brain has been deemed the most complex organ and has captivated neuroscientists for decades. Most studies of this organ have relied on reductionist model systems. Although all model systems are essentially wrong, cerebral organoids so far represent the closest recapitulation of human brain development and disease both in terms of cell diversity and organization. The optogenetic technique can be used in this context to study the functional neuroanatomy of the brain, to examine the neural circuits, and to determine the etiology of neurological disorders. In this opinion article, we suggest ways in which optogenetics can be combined with cerebral organoids to allow unprecedented precision and accuracy in studying normal and aberrant neurodevelopmental processes and, as well, neurodegenerative diseases.

5.
Stem Cell Res Ther ; 10(1): 191, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31248450

RESUMO

BACKGROUND: WNT and TGFß signaling pathways play critical regulatory roles in cardiomyocyte fate determination and differentiation. MiRNAs are also known to regulate different biological processes and signaling pathways. Here, we intended to find candidate miRNAs that are involved in cardiac differentiation through regulation of WNT and TGFß signaling pathways. METHODS: Bioinformatics analysis suggested hsa-miR-335-3p and hsa-miR-335-5p as regulators of cardiac differentiation. Then, RT-qPCR, dual luciferase, TOP/FOP flash, and western blot analyses were done to confirm the hypothesis. RESULTS: Human embryonic stem cells (hESCs) were differentiated into beating cardiomyocytes, and these miRNAs showed significant expression during the differentiation process. Gain and loss of function of miR-335-3p and miR-335-5p resulted in BRACHYURY, GATA4, and NKX2-5 (cardiac differentiation markers) expression alteration during the course of hESC cardiac differentiation. The overexpression of miR-335-3p and miR-335-5p also led to upregulation of CNX43 and TNNT2 expression, respectively. Our results suggest that this might be mediated through enhancement of WNT and TGFß signaling pathways. CONCLUSION: Overall, we show that miR-335-3p/5p upregulates cardiac mesoderm (BRACHYURY) and cardiac progenitor cell (GATA4 and NKX2-5) markers, which are potentially mediated through activation of WNT and TGFß signaling pathways. Our findings suggest miR-335-3p/5p to be considered as a regulator of the cardiac differentiation process.

6.
Int J Pharm ; 565: 391-408, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31085260

RESUMO

Safe and efficient delivery of microRNA (miRNA) molecules is essential for their successful transition from research to the clinic setting. In the present study, we have used a bile acid, deoxycholic acid (DA), to modify 1.8 kDa branched polyethylenimine (bPEI1.8) and subsequently investigated gene delivery features of the resultant conjugates (PEI-DAn). We found significant differences between the PEI-DAn conjugates and conventional bPEIs with respect to miRNA condensation ability, buffering capacity, cellular uptake, and intracellular gene release behavior in endothelial cells (ECs) isolated from human umbilical vein (HUVECs). Changes in the conjugation degree greatly influenced the transfection performance of the PEI-DAn conjugates with respect to miRNA condensation and decondensation properties as well as cellular uptake behavior. The PEI-DA3 conjugates could significantly enhance the expression level of miRNA-210 in HUVECs. The overexpressed miRNA-210, in turn, markedly downregulated the expression levels of Efna3 and Ptp1b as well as led to a substantial rise in HUVECs' migration rate in a wound healing assay. Collectively, our results have demonstrated that PEI-DA3 conjugates facilitate the formation of stable nanocomplexes that are loose enough to release miRNAs into the cytosol. The free bioavailable miRNAs, in turn, result in efficient gene silencing comparable to bPEI25 as well as Lipofectamine RNAiMAX.

7.
J Cell Biochem ; 120(10): 16624-16633, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31081256

RESUMO

Clinical and pharmaceutical applications of primary hepatocytes (PHs) are limited due to inadequate number of donated livers and potential challenges in successful maintenance of PHs in culture. Freshly isolated hepatocytes lose their specific features and rapidly de-differentiate in culture. Bipotent hepatoblasts, as liver precursor cells that can differentiate into both hepatocytes and cholangiocytes (Alb- and Ck19-positive cells, respectively), could be used as an alternative and reliable cell source to produce enough PHs for drug discovery or possible clinical applications. In this study, growth factor-free coculture systems of prenatal or postnatal murine liver stromal cells (pre-LSCs or post-LSCs, respectively) were used as feeder cells to support freshly isolated mice hepatoblasts. DLK1-positive hepatoblasts were isolated from mouse fetuses (E14.5) and cocultured with feeder cells under adherent conditions. The hepatoblasts' bipotent features, proliferation rate, and colony formation capacity were assessed on day 5 and 7 post-seeding. Immunofluorescence staining showed that the hepatoblasts remained double positive for Alb and Ck19 on both Pre- and Post-LSCs, after 5 and 7 days of coculture. Moreover, application of pre-LSCs as feeder cells significantly increased the number of DLK1-positive cells and their proliferation rate (ie, increased the number of Ki-67 positive cells) on day 7, compared to Post-LSCs group. Finally, to address our ultimate goal, which was an extension of hepatoblasts ex vivo maintenance, 3D spheres of isolated hepatoblasts were, cultured in conditioned medium (CM) derived from pre-LSCs until day 30. It was observed that the CM derived from Pre-LSCs could successfully prolong the maintenance of hepatic progenitor cells (HPCs) in 3D suspension culture.

8.
Urol J ; 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31004339

RESUMO

INTRODUCTION: This clinical study evaluated the effect of autologous muscle-derived cell (MDC) injection for the treatment of female patients with pure stress urinary incontinence (SUI). MATERIALS AND METHODS: A total of 20 women with SUI received transurethral injections of autologous MDCs. Baseline and follow-up evaluations consisted of physical examinations (cough stress tests), one-hour pad test, Incontinence Impact Questionnaire-7 (IIQ-7), and Urogenital Distress Inventory (UDI-6) scoring. The patients were followed one week as well as 1, 3, 6, 9, 12, and 24 month(s) after the procedure. Multichannel urodynamic study was performed before and 24 months after the intervention. The incidence and severity of adverse events (AE) were also recorded at each follow-up visit. RESULTS: A total of 20 eligible female patients with the chief complaint of SUI that was unresponsive to conservative management, was enrolled in the trial, 17 of whom completed all follow-up visits. At 12th months, 10 (59%) patients had complete response, whereas 2 (12%) and 5 (29%) patients had partial and no response, respectively.  At 24th months, relapse of SUI in 5 out of 10 complete responders (29%) and 2 out of 2 partial responders to the treatment, respectively. The intervention produced no serious AE during the trial. CONCLUSION: According to our results, though obtained from a limited number of patients, MDC therapy was a minimally invasive and safe procedure for treatment of female patients with pure SUI.  However, currently, the efficacy of this type of treatment for SUI is not sufficiently high and multi-center randomized clinical trials are required to be conducted before reaching a concrete conclusion.

9.
Exp Cell Res ; 379(2): 225-234, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30981668

RESUMO

This study aims to prepare intermediate mesoderm-like cells from mouse embryonic fibroblasts (MEFs). In the first step, intermediate mesoderm-like cells (IMLCs) and renal epithelial-like cells (RELCs) were extracted from mouse embryonic stem cells (mESCs) in a specified media that contained two small molecules, CHIR99021 and TTNPB, along with growth factors, FGF9and BMP7. Then, MEFs were directly converted into IM by genes for the pluripotency factors, which encode the transcription factors; Oct4, Sox2, Klf4, and c-Myc (OSKM). These unstable intermediate cells were quickly encouraged to form IM with the assistance of CHIR99021 and TTNPB. The results showed that exogenous expression of OSKM factors for four days was adequate to generate partially reprogrammed cells (SSEA1+/Nanog-). Real-time PCR and immunocytochemistry analysis confirmed the presence of the MEF-derived IMs. This study introduced a method for mESCs differentiation to RELCs followed by MEF conversion in an attempt to generate IM by circumventing pluripotency.

10.
J Cell Physiol ; 234(11): 20742-20754, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31004353

RESUMO

A large number of treatment approaches have been used for spinal cord injury improvement, a medically incurable disorder, and subsequently stem cell transplantation appears to be a promising strategy. The main objective of this study is to ascertain whether combinational therapy of human neural stem cells (hNSCs) together with lithium chloride improves cell survival, proliferation, and differentiation in a rat spinal contusion model, or not. Contusive spinal cord injury was implemented on Wistar male rats. Experimental groups comprised of: control, hNSCs transplanted, lithium chloride (Li), and hNSCs and lithium chloride (hNSCs + Li). In every experimental group, locomotor activity score and motor evoked potential (MEP) were performed to evaluate motor recovery as well as histological assessments to determine mechanisms of improvement. In accordance with our results, the hNSCs + Li and the Li groups showed significant improvement in locomotor scores and MEP. Also, Histological assessments revealed that transplanted hNSCs are capable of differentiation and migration along the spinal cord. Although NESTIN-positive cells were proliferated significantly in the Lithium group in comparison with control and the hNSCs + Li groups, the quantity of ED1 cells in the hNSCs + Li was significantly larger than the other two groups. Our results demonstrate that combinational therapy of hNSCs with lithium chloride and lithium chloride individually are adequate for ameliorating more than partial functional recovery and endogenous repair in spinal cord-injured rats.

11.
Mater Sci Eng C Mater Biol Appl ; 101: 64-75, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029357

RESUMO

Recruitment of mesenchymal stem cells (MSCs) to an injury site and their differentiation into the desired cell lineage are implicated in deficient bone regeneration. To date, there is no ideal structure that provides these conditions for bone regeneration. In the current study, we aim to develop a novel scaffold that induces MSC migration towards the defect site, followed by their differentiation into an osteogenic lineage. We have fabricated a gelatin/nano-hydroxyapatite (G/nHAp) scaffold that delivered cannabidiol (CBD)-loaded poly (lactic-co-glycolic acid) (PLGA) microspheres to critical size radial bone defects in a rat model. The fabricated scaffolds were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and then analyzed for porosity and degradation rate. The release profile of CBD from the PLGA microsphere and CBD-PLGA-G/nHAp scaffold was analyzed by fluorescence spectroscopy. We performed an in vitro assessment of the effects of CBD on cellular behaviors of viability and osteogenic differentiation. Radiological evaluation, histomorphometry, and immunohistochemistry (IHC) analysis of all defects in the scaffold and control groups were conducted following transplantation into the radial bone defects. An in vitro migration assay showed that CBD considerably increased MSCs migration. qRT-PCR results showed upregulated expression of osteogenic markers in the presence of CBD. Histological and immunohistochemical findings confirmed new bone formation and reconstruction of the defect at 4 and 12 week post-surgery (WPS) in the CBD-PLGA-G/nHAp group. Immunofluorescent analysis revealed enhanced migration of MSCs into the defect areas in the CBD-PLGA-G/nHAp group in vivo. Based on the results of the current study, we concluded that CBD improved bone healing and showed a critical role for MSC migration in the bone regeneration process.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/patologia , Canabidiol/farmacologia , Células-Tronco Mesenquimais/citologia , Microesferas , Osseointegração/efeitos dos fármacos , Tecidos Suporte/química , Animais , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/cirurgia , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Osteogênese/efeitos dos fármacos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos Wistar , Cicatrização/efeitos dos fármacos , Microtomografia por Raio-X
12.
J Cell Physiol ; 234(10): 18697-18706, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30912162

RESUMO

Generating neural stem cells (NSCs) from astroglia as an abundant cell type in the mammalian brain has a promising outlook to be used in cell-replacement therapy for treatment of neurodegenerative disorders and neuronal trauma. However, little is known about a single reprogramming factor that may lead to the generation of induced NSCs (iNSCs) from adult brain-derived astrocytes in the absence of extrinsic inductive signals. Here, we show that zinc-finger nuclear protein Zfp521 alone is sufficient for converting the adult mouse brain-derived astrocytes into iNSCs. In vitro, Zfp521-iNSCs demonstrated long-term self-renewal and multipotency and expressed related markers. Moreover, single-seeded iNSCs were able to produce NSC colonies. These results suggest that application of Zfp521 to generate iNSCs could be regarded as a new approach for conversion of resident astrocytes into iNSCs in cell therapy for in vivo treatment of neural injuries.

13.
Biofactors ; 45(3): 427-438, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30907984

RESUMO

One of the major issues in cell therapy of myocardial infarction (MI) is early death of engrafted cells in a harsh oxidative stress environment, which limits the potential therapeutic utility of this strategy in the clinical setting. Increasing evidence implicates beneficial effects of omega-3 fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and ascorbic acid (AA) in cardiovascular diseases, in particular their role in ameliorating fibrosis. In the current study, we aim to assess the cytoprotective role of EPA + DHA and AA in protecting embryonic stem cell (ESC)-derived cardiac lineage cells and amelioration of fibrosis. Herein, we have shown that preincubation of the cells with EPA + DHA + AA prior to H2 O2 treatment attenuated generation of reactive oxygen species (ROS) and enhanced cell viability. Gene expression analysis revealed that preincubation with EPA + DHA + AA followed by H2 O2 treatment, upregulated heme oxygenase-1 (HO-1) along with cardiac markers (GATA4, myosin heavy chain, α isoform [MYH6]), connexin 43 [CX43]) and attenuated oxidative stress-induced upregulation of fibroblast markers (vimentin and collagen type 1 [Col1]). Alterations in gene expression patterns were followed by marked elevation of cardiac troponin (TNNT2) positive cells and reduced numbers of vimentin positive cells. An injection of EPA + DHA + AA-pretreated ESC-derived cardiac lineage cells into the ischemic myocardium of a rat model of MI significantly reduced fibrosis compared to the vehicle group. This study provided evidence that EPA + DHA + AA may be an appropriate preincubation regimen for regenerative purposes. © 2019 BioFactors, 45(3):427-438, 2019.

14.
ACS Chem Neurosci ; 10(3): 1214-1221, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30644730

RESUMO

Bipolar disorder is a complex neuropsychiatric disorder, characterized by intermittent episodes of mania and depression. Recent studies have indicated argyrophilic grains, composed of hyperphosphorylated tau, are observable in postmortem brains of bipolar patients. It remains uncertain how tau hyperphosphorylation results in neurodegeneration upon the disease. Recent studies have demonstrated that phosphorylated tau at Thr231 exists in two distinct cis and trans conformations, in which cis pT231-tau is highly neurotoxic and acts as an early driver of tauopathy in several neurodegenerative diseases. We herein employed an in vitro model, which resembles some aspects of bipolar disorder, to study the cis p-tau mediatory role. We established GSK3ß overexpressing SH-SY5Y cells and examined cell viability, cis p-tau formation, and lithium effects by immunofluorescence and flow cytometry. We found an increase in cis p-tau levels as well as viability decrease in the cell model. Furthermore, we discovered that lithium treatment inhibits cis p-tau formation, resulting in diminished cell death. We also examined BD and healthy human brain samples and detected cis p-tau in the patients' brains. Our results show that tauopathy, observed in bipolar disorder, is being mediated through cis p-tau and that a conformer could be the cause of neurodegeneration upon the disease. Our findings would suggest novel therapeutic target to fight the devastating disorder.

15.
Int J Pharm ; 558: 299-310, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30654056

RESUMO

Microneedle patches have been widely used as transdermal transport systems because of their painless and easy application. Marked rigidity, strength, biocompatibility, and physiological stability are unique features of microneedles fabricated from ceramic materials to be used as microneedle patches. However, the conventional ceramic microneedles are typically dense structures with limited free space for biomolecule loading. A facile method is required for fabrication of biocompatible ceramic microneedles with interconnected porosity. Herein, the simple method of centrifugal casting was developed for fabrication of microporous microneedles from alumina suspensions. The slurry or resin-based alumina suspensions were casted into micromolds under centrifugal force, followed by sintering at high temperatures. The effects of particle size, solvent type, binder amount, resin content and sintering temperature on the microstructure and mechanical properties of microneedles were investigated. By optimizing the process parameters, highly porous (up to 60%) microneedles with interconnected micropores (of diameter ∼1-1.5 µm) were produced. The microporous microneedles were biocompatible and mechanically strong for skin penetration. The potential use of the microneedles for transdermal transportation of biomolecules was shown by fast and accurate extraction of glucose from a skin model and efficient loading and fast release of insulin under physiological conditions. The results suggested that the microporous alumina microneedles may serve as molecular transport systems in transdermal biosensing and drug delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Agulhas , Adesivo Transdérmico , Administração Cutânea , Óxido de Alumínio , Animais , Glucose/química , Humanos , Hidrogéis/química , Insulina/administração & dosagem , Microinjeções , Ratos , Pele/metabolismo
16.
Biomater Sci ; 7(4): 1422-1436, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30666997

RESUMO

Extracellular matrix-derived scaffolds provide an efficient platform for the generation of organ-like structures. Successful development of testicular organoids (TOs) with the capability of supporting complete spermatogenesis has not been reported yet. Here, we have developed an optimized method for the decellularization of ram testicular tissue fragments. Our findings showed that testicular fragments treated with a serial combination of Triton X-100 and SDS in PBS for 48 h resulted in the efficient removal of cellular materials and retention of the extracellular matrix (ECM) components. In order to fabricate testis-derived scaffolds (TDSs), the testicular ECM (T-ECM) was digested in acid/pepsin, followed by neutralization of pre-gel solution to form a hydrogel. Then, the hydrogels were freeze-dried and cross-linked using a chemical method. To reach the optimal concentration for the T-ECM in the fabrication of TDSs, the scaffold properties including porosity, pore size, swelling behavior, and degradation were evaluated. Our study suggested that 25 mg ml-1 of the T-ECM is the best concentration for the fabrication of macroporous TDSs for demonstrating lower pore size, homogeneously distributed pores, and a higher swelling ratio. Furthermore, inoculation of neonatal mouse testicular cells onto TDSs resulted in the generation of multicellular TOs in which the differentiation of spermatogonial cells into post-meiotic cells was confirmed. Hormonal analysis of TDSs revealed the functionality of TOs in the secretion of testosterone and inhibin B. The current study also demonstrated that macroporous TDSs could provide a novel platform for testicular tissue engineering and in vitro spermatogenesis.


Assuntos
Organoides/química , Testículo/química , Animais , Matriz Extracelular/química , Masculino , Camundongos , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Engenharia Tecidual
17.
Biomaterials ; 192: 537-550, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30529872

RESUMO

Human cardiomyocytes (CM) differentiated from pluripotent stem cells (PSCs) are relatively immature when generated in two-dimensional (2D) in vitro cultures, which limits their biomedical applications. Here, we devised a strategy to enhance maturation of human CM in vitro by assembly of three-dimensional (3D) cardiac organoids (CO) containing human embryonic stem cell-derived cardiac progenitor cells (hESC-CPCs), endothelial cells (ECs), and mesenchymal stem cells (MSCs). In contrast to corresponding 2D cultures, 3D CO not only developed into structures containing spontaneously beating CM, but also showed enhanced maturity as indicated by increased expressions of sarcomere and ion channel genes and reduced proliferation. Heterotopic implantation of CO into the peritoneal cavity of immunodeficient mice induced neovascularization, and further stimulated upregulation of genes coding for the contractile apparatus, Ca2+ handling and ion channel proteins. In addition, CM in implanted CO were characterized by a more mature ultrastructure compared to CM implanted without CO support. Functional analysis revealed the presence of working cardiomyocytes in both in vivo and ex ovo chorioallantoic membrane implanted CO. Our results demonstrate that cultivation in 3D CO and subsequent heterotopic implantation enhance maturation of CM towards an adult-like phenotype. We reason that CO-derived CM represent an attractive source for drug discovery and other biomedical applications.

18.
Iran Biomed J ; 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30501144

RESUMO

Background: Two of the Wnt signaling pathway target genes; tumor necrosis factor receptor family member (TROY) and leucine-rich G-protein coupled receptor (LGR5), are involved in the generation and maintenance of gastrointestinal epithelium. A negative modulatory role has recently been assigned to TROY, in this pathway. Here, we have examined their simultaneous expression in gastric carcinogenesis. Methods: Tumor and paired adjacent tissues of intestinal-type gastric cancer (GC) patients (n = 30) were evaluated for LGR5 and TROY expression by immunohistochemistry. The combination of the percentage of positively¬ stained cells and the intensity of staining was defined as the composite score and compared between groups. The obtained findings were re-evaluated in a mouse model. Results: TROY expression in the tumor tissue was significantly lower than that of the adjacent tissue (2.5 ± 0.9 vs. 3.3 ± 0.9, p = 0.004), which was coincident with higher LGR5 expression (3.6 ± 1.1 vs. 2.7 ± 0.9, p = 0.001). This observation was prominent at stages II/III of GC, leading to a statistically significant mean difference of expression between these two molecules (p = 0.005). In the H. pylori infected-mouse model, this inverse expression was observed in transition from early (8-16 w) to late (26-50 w) time points, post treatment (p = 0.002). Conclusion: Our data demonstrates an inverse trend between TROY down-regulation and LGR5 up-regulation in GC tumors, as well as in response to H. pylori infection in mice. These findings support a potential negative modulatory role for TROY on LGR5 expression.

19.
Cell Mol Life Sci ; 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30420999

RESUMO

Embryonic stem cells (ESCs) are immortal stem cells that own multi-lineage differentiation potential. ESCs are commonly derived from the inner cell mass (ICM) of pre-implantation embryos. Due to their tremendous developmental capacity and unlimited self-renewal, ESCs have diverse biomedical applications. Different culture media have been developed to procure and maintain ESCs in a state of naïve pluripotency, and to preserve a stable genome and epigenome during serial passaging. Chromatin modifications such as DNA methylation and histone modifications along with microRNA activity and different signaling pathways dynamically contribute to the regulation of the ESC gene regulatory network (GRN). Such modifications undergo remarkable changes in different ESC media and determine the quality and developmental potential of ESCs. In this review, we discuss the current approaches for derivation and maintenance of ESCs, and examine how differences in culture media impact on the characteristics of pluripotency via modulation of GRN during the course of ICM outgrowth into ESCs. We also summarize the current hypotheses concerning the origin of ESCs and provide a perspective about the relationship of these cells to their in vivo counterparts (early embryonic cells around the time of implantation). Finally, we discuss generation of ESCs from human embryos and domesticated animals, and offer suggestions to further advance this fascinating field.

20.
J Cell Physiol ; 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30378105

RESUMO

Mesenchymal stromal cells (MSCs) can effectively contribute to tissue regeneration inside the inflammatory microenvironment mostly through modulating immune responses. MSC-derived extracellular vesicles (MSC-EVs) display immunoregulatory functions similar to parent cells. Interactions between MSC-EVs and immune cells make them an ideal therapeutic candidate for infectious, inflammatory, and autoimmune diseases. These properties of MSC-EVs have encouraged researchers to perform extensive studies on multiple factors that mediate MSC-EVs immunomodulatory effects. Investigation of proteins involved in the complex interplay of MSC-EVs and immune cells may help us to better understand their functions. Here, we performed a comprehensive proteomic analysis of MSC-EVs that was previously reported by ExoCarta database. A total of 938 proteins were identified as MSC-EV proteome using quantitative proteomics techniques. Kyoto Encyclopedia of Genes and Genomes analysis demonstrates that ECM-receptor interaction, focal adhesion, and disease-specific pathways are enriched in MSC-EVs. By detail analysis of proteins presence in immune system process, we found that expression of some cytokines, chemokines, and chemokine receptors such as IL10, HGF, LIF, CCL2, VEGFC, and CCL20, which leads to migration of MSC-EVs to injured sites, suppression of inflammation and promotion of regeneration in inflammatory and autoimmune diseases. Also, some chemoattractant proteins such as CXCL2, CXCL8, CXCL16, DEFA1, HERC5, and IFITM2 were found in MSC-EV proteome. They may actively recruit immune cells to the proximity of MSC or MSC-EVs, may result in boosting immune response under specific circumstances, and may have protective role in infectious diseases. In this review, we summarize available information about immunomodulation of MSC-EVs with particular emphasis on their proteomics analysis.

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