Astaxanthin effectiveness in preventing multiple sclerosis in animal model.

OBJECTIVE: The aim of the present study was to reveal the effect of therapeutic and prophylactic potential of astaxanthin in experimental autoimmune encephalomyelitis (EAE) as an acceptable model for the study of multiple sclerosis (MS). BACKGROUND: Astaxanthin has powerful antioxidant activities as well as several essential biological functions while multiple sclerosis prevention is highly regarded by researchers. METHODS: The astaxanthin potential in prevention of multiple sclerosis was examined in the chronic model of experimental autoimmune encephalomyelitis (EAE) by using female C57BL/6 mice induced with oligodendrocyte glycoprotein (MOG). Splenocytes were assessed to measure the levels of proinflammatory and anti-inflammatory cytokines, proliferation rate and FoxP3+Treg cell frequency. Immunohistochemical examinations were performed on spinal cord and brain tissue. RESULTS: Astaxanthin reduced splenocytes proliferation index and proinflammatory cytokine levels, and vice versa increased the anti-inflammatory cytokine levels. Immunohistochemical studies of the spinal cord and brain showed that the infiltration with inflammatory cells was highly confined in the central nervous system. Protective effects of astaxanthin were visible by assigning low score recording in clinical behavior and disease severity. CONCLUSION: Astaxanthin is a powerful tool for intervention in EAE on a model of multiple sclerosis, so it can be studied further to prevent and treat MS (Tab. 2, Fig. 3, Ref. 41).

Stemness of spermatogonial stem cells encapsulated in alginate hydrogel during cryopreservation.

This study investigated the effect of spermatogonial stem cell encapsulated in alginate hydrogel during cryopreservation, as cells were protected against damage during cryopreservation within the hydrogel. Spermatogonial stem cells were isolated from the testes of Balb/c mice pups (6 days old), purified in laminin-coated dishes and CD90.1 microbeads, encapsulated in alginate hydrogel and then cryopreserved. After thawing, cell viability and Spermatogonial stem cell (SSC) colony diameter were evaluated. After RNA was isolated and cDNA was synthesised, the expression of stemness genes was considered using RT real-time PCR. Finally, spermatogonial stem cells labelled with BrdU were transplanted to busulfan azoospermic mouse models. Lin28a and Sall4 genes were significantly upregulated after cryopreservation in alginate hydrogel. However, cell viability was significantly decreased. The diameter of colonies consisting of spermatogonial stem cells freeze-thawed in alginate microbeads showed no significant difference with fresh spermatogonial stem cells and the control group. The injection of freeze-thawed spermatogonial stem cells encapsulated in alginate hydrogel resulted in spermatogenesis recovery. Alginate mimics the extracellular matrices (ECM) for spermatogonial stem cells; therefore, it can support stemness potential during the cell cryopreservation process and restart spermatogenesis after transplantation.

Effect of silibinin and trans-chalcone in an Alzheimer's disease-like model generated by insulin amyloids.

Amyloid fibrils are characteristic of several disorders including Alzheimer's disease (AD), with no cure or preventive therapy. Diminishing amyloid deposits using aromatic compounds is an interesting approach toward AD treatment. The present study examined the anti-fibrillogenic effects of silibinin and trans-chalcone in vitro, in vivo, and in silico on insulin amyloids. In vitro incubation of insulin at 37°C for 24 h induced amyloid formation. Addition of trans-chalcone and silibinin to insulin led to reduced amounts of fibrils as shown by thioflavin S fluorescence and Congo red absorption spectroscopy, with a better effect observed for silibinin. In vivo bilateral injection of fibrils formed by incubation of insulin in the presence or absence of silibinin and trans-chalcone or insulin fibrils plus the compounds in rats' hippocampus was performed to obtain AD characteristics. Passive avoidance (PA) test showed that treatment with both compounds efficiently increased latency compared with the model group. Histological investigation of the hippocampus in the cornu ammonis (CA1) and dentate gyrus (DG) regions of the rat's brain stained with hematoxylin-eosin and thioflavin S showed an inhibitory effect on amyloid aggregation and markedly reduced amyloid plaques. In silico, a docking experiment on native and fibrillar forms of insulin provided an insight onto the possible binding site of the compounds. In conclusion, these small aromatic compounds are suggested to have a protective effect on AD.

Effect of silibinin and trans-chalcone in an Alzheimer's disease-like model generated by insulin amyloids

Amyloid fibrils are characteristic of several disorders including Alzheimer's disease (AD), with no cure or preventive therapy. Diminishing amyloid deposits using aromatic compounds is an interesting approach toward AD treatment. The present study examined the anti-fibrillogenic effects of silibinin and trans-chalcone in vitro, in vivo, and in silico on insulin amyloids. In vitro incubation of insulin at 37°C for 24 h induced amyloid formation. Addition of trans-chalcone and silibinin to insulin led to reduced amounts of fibrils as shown by thioflavin S fluorescence and Congo red absorption spectroscopy, with a better effect observed for silibinin. In vivo bilateral injection of fibrils formed by incubation of insulin in the presence or absence of silibinin and trans-chalcone or insulin fibrils plus the compounds in rats' hippocampus was performed to obtain AD characteristics. Passive avoidance (PA) test showed that treatment with both compounds efficiently increased latency compared with the model group. Histological investigation of the hippocampus in the cornu ammonis (CA1) and dentate gyrus (DG) regions of the rat's brain stained with hematoxylin-eosin and thioflavin S showed an inhibitory effect on amyloid aggregation and markedly reduced amyloid plaques. In silico, a docking experiment on native and fibrillar forms of insulin provided an insight onto the possible binding site of the compounds. In conclusion, these small aromatic compounds are suggested to have a protective effect on AD.

Efficient Production of Hepatocyte-like Cells from Human-induced Pluripotent Stem Cells by Optimizing Growth Factors.

BACKGROUND: Generating hepatocytes with complete liver functions is still a challenge and developing more functional hepatocytes is needed. OBJECTIVE: To compare various differentiation factors and protocols and introducing a preferable protocol to differentiate human-induced pluripotent stem cells (hiPSCs) into hepatocyte-like cells (HLCs). METHODS: After 3 days of the endoderm differentiation of hiPSCs, the cells were incubated with 5 hepatocyte differentiation culture media, protocols (P), for 14 days-P1: hepatocyte growth factor and fibroblast growth factor-4 (FGF-4) for the first week and oncostatin-M and dexamethasone for the second week; P2: similar to P1 but FGF4 was used in both the first and second weeks; P3: similar to P1 but FGF-4 was not used; P4: similar to P1 but FGF-4 and dexamethasone were not used; and P5: similar to P1 but FGF-4 and oncostatin-M were not used. After 17 days, characterization was done by qRT-PCR, immunofluorescence and ELISA. RESULTS: The mRNA expression levels of hepatocyte markers (albumin, cytokeratin-18, tyrosine aminotransferase, hepatocyte nuclear factor-4α, cytochrome-P450 7A1) increased significantly (p<0.05) in the differentiated cells by 5 different protocols. Furthermore, significant protein expression and secretion of albumin were detected in the differentiated cells by 5 different protocols. In P3, the differentiated cells had the highest exhibit of hepatocyte characteristics and in P4 they had the lowest. Moreover, in P1 and P2 similar results were observed. CONCLUSION: Since P3 gave us the best results among all protocols, we recommend it as an efficient protocol to differentiate the functional HLCs from hiPSCs, which can improve cell therapies.

Gd3+-DTPA-bis (N-methylamine) - anionic linear globular Dendrimer-G1; a more efficient MRI contrast media.

By advancing of molecular imaging techniques, magnetic resonance imaging (MRI) is becoming an increasingly important tool in early diagnosis. Researchers have found new ways to increase contrast of MRI images.Therefore some types of drug known as contrast media are produced. Contrast media improve the visibility of internal body structures in MRI images. Gadodiamide (Omniscan®) is one of these contrast media which is produced commercially and used clinically. In this study Gadodiamide was first synthesized and then qualitative and quantitative methods were carried out to ensure the proper synthesis of this drug then to increase the efficiency of this contrast medium use dendrimer that is one kind of nano particle. This dendrimer has a polyethylene glycol (PEG) core and citric acid branches. After dendrimer attached to Gadodiamide to ensure the proper efficient connection between them the stability studies were carried out and cytotoxicity of the drug was evaluated. Finally, after ensuring the non-toxicity of the drug, in vivo studies (injected into mice) MR imaging was performed to examine the impact of synthesis drug on the resolution of image.The result obtained from this study demonstrated that the attachment of Gadodiamide to dendrimer reduces its cytotoxicity and also improved resolution of image. Also the new contrast media (Gd3+-DTPA- bis [N-methylamine] - Dendrimer) - unlike Omniscan® - is biodegradable and able to enter the HEPG2 cell line. The results confirm the hypothesis that using dendrimer to synthesize this new nano contrast medium increases its effectiveness.

Isomalt production by cloning, purifying and expressing of the MDH gene from Pseudomonas fluorescens DSM 50106 in different strains of E. coli.

A NADH-dependent mannitol dehydrogenase gene (mtlD) was cloned from Pseudomonas fluorescens, subcloned into an expression vector (pDEST110) and entered into different strains of E. coli to compare their protein expression and the enzyme specific activity. Purifications were accomplished by Ni(2+)-NTA affinity chromatography. Using this approach, the efficiency of purification process significantly increased (up to 90%) so that the purified enzyme gave a sharp single band (55 kDa) in SDS-PAGE. The results showed that among the strains, BL21 (DE3) plysS exhibited the maximum expression level of MDH(mannitol dehydrogenase) (11 mg L(-1)). Results from activity assay with fructose as substrate also showed that in this strain the specific activity of 63 U mg(-1) protein monitored for the enzyme, the record not reported before. Resazurin staining also indicated that the enzyme reduced fructose, whereas oxidized other substrates including mannitol, sorbitol and arabitol under optimal assay condition. From HPLC analysis it was showed for the first time that the enzyme could convert substrate isomaltulose to the specific products, GPM and GPS. Interestingly, because of the high specificity of the enzyme for substrate, the method can be used as an alternative approach to substitute nonspecific conventional method of isomalt production.