Human Mesenchymal Stem Cells Seeded on the Natural Membrane to Neurospheres for Cholinergic-like Neurons

This study aimed to differentiate human mesenchymal stem cells (hMSCs) from the human umbilical cord in cholinergic-like neurons using a natural membrane. The isolation of hMSCs from Wharton’s jelly (WJ) was carried out using “explant” and mononuclear cells by the density gradient from umbilical blood and characterized by flow cytometry. hMSCs were seeded in a natural functional biopolymer membrane to produce neurospheres. RT-PCR was performed on hMSCs and neurospheres derived from the umbilical cord. Neural precursor cells were subjected to a standard cholinergic-like neuron differentiation protocol. Dissociated neurospheres, neural precursor cells, and cholinergic-like neurons were characterized by immunocytochemistry. hMSCs were CD73+, CD90+, CD105+, CD34- and CD45- and demonstrated the trilineage differentiation. Neurospheres and their isolated cells were nestin-positive and expressed NESTIN, MAP2, ßIII-TUBULIN, GFAP genes. Neural precursor cells that were differentiated in cholinergic-like neurons expressed ßIII-TUBULIN protein and choline acetyltransferase enzyme. hMSCs seeded on the natural membrane can differentiate into neurospheres, obtaining neural precursor cells without growth factors or gene transfection before cholinergic phenotype differentiation.

Differentiation of human mesenchymal stem cells through the natural matrix to neurospheres for cholinergic-like cells

Background

In Alzheimer's Disease there is an impairment of the cholinergic system, causing loss of neurons, impairment of intellectual abilities. In this context, the mesenchymal stem cells (MSC) and its applications in cell therapies become target of the research, which may contribute to the treatment of neurodegenerative diseases. Through the differentiation potential of MSCs, prospecting functional repair of the injured tissue from cholinergic neuronal cells could be a potential treatment. The aims was to evaluate the possibility of differentiation of MSCs from the human umbilical cord in nestin-positive neural precursor cells (NPCN+) through the NFBX into cholinergic ‘like’ cells.

Methods

The isolation of hMSCs from Wharton's jelly (WJ) was by the explant and mononuclear cells by density gradient. hMSCs were plating in natural matrix as NFBX for neurospheres production. Neural precursor cells were subjected to standard cholinergic differentiation protocol. Dissociated neurospheres, neural precursor cells and cholinergic-like cells were characterized by immunocytochemistry. The RT-PCR was done.

Results

hMSCs were CD73+, CD90+, CD105+, CD34- and CD45- and demonstrated the trilineage differentiation. Neurospheres and their isolated cells were nestin positive, and also expressed NESTIN, MAP2, ßIII-TUBULIN, GFAPgenes. Neural precursor cells that were differentiated in cholinergic-like cells expressed ßIII-TUBULIN protein and choline acetyltransferase enzyme.

Conclusions

hMSCs on the natural matrix were capable of differentiating hMSC into neurospheres, obtaining neural precursor cells without growth factors or gene transfection before cholinergic differentiation.

Nanostructured Cellulose-Gellan-Xyloglucan-Lysozyme Dressing Seeded with Mesenchymal Stem Cells for Deep Second-Degree Burn Treatment

PURPOSE

In deep burns, wound contraction and hypertrophic scar formation can generate functional derangement and debilitation of the affected part. In order to improve the quality of healing in deep second-degree burns, we developed a new treatment in a preclinical model using nanostructured membranes seeded with mesenchymal stem cells (MSCs).

METHODS

Membranes were obtained by reconstitution of bacterial cellulose (reconstituted membrane [RM]) and produced by a dry-cast process, then RM was incorporated with 10% tamarind xyloglucan plus gellan gum 1:1 and 10% lysozyme (RMGT-LZ) and with 10% gellan gum and 10% lysozyme (RMG-LZ). Membrane hydrophobic/hydrophilic characteristics were investigated by static/dynamic contact-angle measurements. They were cultivated with MSCs, and cell adhesion, proliferation, and migration capacity was analyzed with MTT assays. Morphological and topographic characteristics were analyzed by scanning electron microscopy. MSC patterns in flow cytometry and differentiation into adipocytes and osteocytes were checked. In vivo assays used RMG-LZ and RMGT-LZ (with and without MSCs) in Rattus norvegicus rats submitted to burn protocol, and histological sections and collagen deposits were analyzed and immunocytochemistry assay performed.

RESULTS

In vitro results demonstrated carboxyl and amine groups made the membranes moderately hydrophobic and xyloglucan inclusion decreased wettability, favoring MSC adhesion, proliferation, and differentiation. In vivo, we obtained 40% and 60% reduction in acute/chronic inflammatory infiltrates, 96% decrease in injury area, increased vascular proliferation and collagen deposition, and complete epithelialization after 30 days. MSCs were detected in burned tissue, confirming they had homed and proliferated in vivo.

CONCLUSION

Nanostructured cellulose-gellan-xyloglucan-lysozyme dressings, especially when seeded with MSCs, improved deep second-degree burn regeneration.

Non-Cytotoxic Sulfated Heterorhamnan from Gayralia brasiliensis Green Seaweed Reduces Driver Features of Melanoma Metastatic Progression

Melanoma is a form of skin cancer with high mortality owing to its fast progression and metastatic capacity. The treatments available nowadays are only palliative in advanced stages of the disease. Thus, alternative therapies for cancer treatment are in demand, and molecules from natural sources, such as polysaccharides, could represent new possible therapeutic approaches. Polysaccharides of freshwater and marine algae with biological activities, such as antitumor properties, are greatly reported in the scientific literature. In the present study, a sulfated heterorhamnan obtained from the green seaweed Gayralia brasiliensis (Gb1 fraction) was chemically characterized and its biological activities in the B16-F10 murine melanoma cell line were evaluated. The Gb1 polysaccharidic fraction tested concentrations presented low or absence of cytotoxicity to B16-F10 cells and neither cell proliferation nor cell cycle were altered. Interestingly, Gb1 treatment decreased B16-F10 cells migration and invasion capabilities and CD44 labeling, showing to be a promising compound for further in vitro and in vivo antitumor studies.

Immune-mediated febrile response in female rats: Role of central hypothalamic mediators

Lipopolysaccharide (LPS) induces fever through cytokines like receptor-activator of nuclear factor κB ligand (RANKL), triggering mediators like prostaglandins (PG), endothelin-1 (ET-1), corticotrophin-releasing factor (CRF), substance P (SP) and endogenous opioids. LPS-induced fever is reduced in females compared with males except in ovariectomized (OVX) females which show increased fever mediated by PG. The present study aimed to identify the mediators involved in fever in intact and OVX female rats. Fever was induced with LPS (50 μg/kg) intraperitoneally or CRF (2.5 μg), ET-1 (1 pg), morphine (10 μg) and SP (500 ng) intracerebroventricularly in sham-operated and OVX rats. The role of RANKL was evaluated with osteoprotegerin (OPG, 1 μg, intracerebroventricularly). Expression of RANK, CRFI/II, ETB, μ-opioid (MOR) and NK1 receptors was evaluated by confocal microscopy. Besides LPS, only morphine induced fever in OVX rats while all mediators induced fever in sham-operated animals. OPG abolished LPS-induced fever in OVX but not sham-operated animals. Overall, fever involves similar central mediators in cycling females and males but only morphine induced fever in OVX females. Importantly, RANK/RANKL participates in LPS-induced fever in OVX females, as in males but not in cycling females.

Fluorescence properties of curcumin-loaded nanoparticles for cell tracking

BACKGROUND

Posttransplant cell tracking, via stem cell labeling, is a crucial strategy for monitoring and maximizing benefits of cell-based therapies. The structures and functionalities of polysaccharides, proteins, and lipids allow their utilization in nanotechnology systems.

MATERIALS AND METHODS

In the present study, we analyzed the potential benefit of curcumin-loaded nanoparticles (NPC) using Vero cells (in vitro) and NPC-labeled adipose-derived mesenchymal stem cells (NPC-ADMSCs) (in vivo) in myocardial infarction and sciatic nerve crush preclinical models. Thereafter, transplantation, histological examination, real time imaging, and assessment of tissue regeneration were done.

RESULTS

Transplanted NPC-ADMSCs were clearly identified and revealed potential benefit when used in cell tracking.

CONCLUSION

This approach may have broad applications in modeling labeled transplanted cells and in developing improved stem cell therapeutic strategies.

A low-molecular-weight galactofucan from the seaweed, Spatoglossum schröederi, binds fibronectin and inhibits capillary-like tube formation in vitro

A low-molecular-weight (LMW) heterofucan (designated fucan B) was obtained from the brown seaweed, Spatoglossum schröederi, and its activity as an inhibitor of capillary-like tube formation by endothelial cells (ECs) was analyzed. Chemical, infrared and electrophoretic analyses confirmed the identity of fucan B. In contrast to other LMW fucans, fucan B (0.012-0.1 mg/mL) inhibited ECs capillary-like tube formation in a concentration-dependent manner. In addition, fucan B (0.01-0.05 mg/mL) did not affect ECs proliferation. Fucan B also inhibited ECs migration on a fibronectin-coated surface, but not on laminin- or collagen-coated surfaces. Biotinylated fucan B was used as a probe to identify its localization. Confocal microscopy experiments revealed that biotinylated fucan did not bind to the cell surface, but rather only to fibronectin. Our findings suggest that fucan B inhibits ECs capillary-like tube formation and migration by binding directly to fibronectin and blocking fibronectin sites recognized by cell surface ligands. However, further studies are needed to evaluate the in vivo effects of fucan B.

Female Sex Hormones Influence the Febrile Response Induced by Lipopolysaccharide, Cytokines and Prostaglandins but not by Interleukin-1β in Rats

There are differences in the immune response, and particularly fever, between males and females. In the present study, we investigated how the febrile responses induced by lipopolysaccharide (LPS) and different endogenous pyrogens were affected by female gonadal hormones. The febrile response to i.p. injection of LPS (50 μg/kg) was 40% lower in female rats compared to male or ovariectomised (OVX) female rats. Accordingly, oestrogen replacement in OVX animals reduced LPS-induced fever. Treatment with the prostaglandin synthesis inhibitor indomethacin (2 mg/kg, i.p. 30 min before) reduced the febrile response induced by LPS in both OVX (88%) and sham-operated (71%) rats. In line with the enhanced fever in OVX rats, there was increased expression of cyclooxygenase-2 (COX-2) in the hypothalamus and elevated levels of prostaglandin E₂ (PGE₂ ). In addition, OVX rats were hyper-responsive to PGE₂ injected i.c.v. By contrast to the enhanced fever in response to LPS and PGE₂ , the febrile response induced by i.c.v. injection of interleukin (IL)-1β was unaffected by ovariectomy, whereas the responses induced by tumour necrosis factor (TNF)-α and macrophage inflammatory protein (MIP)-1α were completely abrogated. These results suggest that the mediators involved in the febrile response in females are similar to males, although the reduction of female hormones may decrease the responsiveness of some mediators such as TNF-α and MIP-1α. Compensatory mechanisms may be activated in females after ovariectomy such as an augmented synthesis of COX-2 and PGE₂ .

Fucan effect on CHO cell proliferation and migration

Fucan is a term used to denominate sulfated L-fucose rich polysaccharides. Here, a heterofucan, named fucan B, was extracted from the Spatoglossum schröederi seaweed. This 21.5 kDa galactofucan inhibited CHO-K1 proliferation and migration when fibronectin was the substrate. Fucan B derivatives revealed that such effects depend on their degree of sulfation. Fucan B did not induce cell death, but promoted G1 cell cycle arrest. Western blotting and flow cytometry analysis suggest that fucan B binds to fibronectin and activates integrin, mainly integrin α5β1, which induces FAK/RAS/MEK/ERK activation. FAK activation inhibits CHO-K1 migration on fibronectin and ERK blocks cell cycle progression. This study indicates that fucan B could be applied in developing new antitumor drugs.

Cell death and DNA damage in peritoneal macrophages of mice (Mus musculus) exposed to inorganic lead

Lead is a heavy metal of considerable environmental and occupational concern and there is growing evidence that it is toxic to the human immune system. In this regard, this study examined the effect of lead (Pb) exposure to peritoneal macrophages (Mvarphis) of mice (Mus musculus) cultivated in DMEM medium supplemented with fetal bovine serum, in order to investigate cell damage related to cell death. Cells were exposed to two concentrations of inorganic lead [Pb(II)] for 4, 24 and 72h. Cell viability declined during the treatment, with responses including cell death, cellular damage and DNA damage. Cell death images were found in treated cells with an increase in Bax expression, but the inorganic lead failed to induce the loss of membrane asymmetry (Annexin V conjugates), suggesting that cell death was mainly due to necrosis induction. The effects of Pb(II) on the mechanisms of cell death is not completely understood, but the immunosuppression due to DNA damage and Mvarphis death is discussed here. We have previously shown the effect of inorganic lead in mitochondria and phagocytosis in Mvarphis, suggesting here a pathway for the effect of the metal on mechanisms of cell death, also discussing its effects on the immune system.

Cytotoxic effect of a new 1,3,4-thiadiazolium mesoionic compound (MI-D) on cell lines of human melanoma

The structural characteristics of mesoionic compounds, which contain distinct regions of positive and negative charges associated with a poly-heteroatomic system, enable them to cross cellular membranes and interact strongly with biomolecules. Potential biological applications have been described for mesoionic compounds. 1,3,4-Thiadiazolium mesoionic compound (MI-D), a new mesoionic compound, has been demonstrated to be extremely cytotoxic to B16-F10 murine melanoma cells when compared to fotemustine and dacarbazine, drugs of reference in melanoma treatment protocols, describing inhibition of tumours grown in vitro and in vivo. We now evaluate the effects of mesoionic compound MI-D on different human melanoma cell lines. The drug decreased the viability and proliferation of MEL-85, SK-MEL, A2058 and MEWO cell lines in vitro, showing a considerable cytotoxic activity on these human cells. Adhesion of MEL-85 cells was evaluated in the presence of the drug using different extracellular matrix (ECM) constituents. MI-D decreased MEL-85 adhesion to laminin, fibronectin and matrigel. The morphology and actin cytoskeleton organisation of MEL-85 cells were also modified on MI-D treatment. These results on human melanoma cell lines indicate that MI-D is a very encouraging drug against melanoma, a tumour that is extremely resistant to chemotherapy.