3D-Cultured Adipose-Derived Stem Cell Spheres Using Calcium-Alginate Scaffolds for Osteoarthritis Treatment in a Mono-Iodoacetate-Induced Rat Model

Osteoarthritis (OA) is a degenerative disease that causes pain, cartilage deformation, and joint inflammation. Mesenchymal stem cells (MSCs) are potential therapeutic agents for OA treatment. However, the 2D culture of MSCs could potentially affect their characteristics and functionality. In this study, calcium-alginate (Ca-Ag) scaffolds were prepared for human adipose-derived stem cell (hADSC) proliferation with a homemade functionally closed process bioreactor system; the feasibility of cultured hADSC spheres in heterologous stem cell therapy for OA treatment was then evaluated. hADSC spheres were collected from Ca-Ag scaffolds by removing calcium ions via ethylenediaminetetraacetic acid (EDTA) chelation. In this study, 2D-cultured individual hADSCs or hADSC spheres were evaluated for treatment efficacy in a monosodium iodoacetate (MIA)-induced OA rat model. The results of gait analysis and histological sectioning showed that hADSC spheres were more effective at relieving arthritis degeneration. The results of serological and blood element analyses of hADSC-treated rats indicated that the hADSC spheres were a safe treatment in vivo. This study demonstrates that hADSC spheres are a promising treatment for OA and can be applied to other stem cell therapies or regenerative medical treatments.

Engineered cell-laden thermosensitive poly(N-isopropylacrylamide)-immobilized gelatin microspheres as 3D cell carriers for regenerative medicine

Several studies have focused on using cell carriers to solve the problem of mesenchymal stem cell expansion on regenerative medicine. However, the disadvantages of using prolonged enzymatic treatment and low cell harvest efficiency still trouble researchers. In this study, PNIPAAm-immobilized gelatin microspheres (abbreviated as GNMS) were synthesized using a simple power-driven flow-focusing microinjection system. The developed thermosensitive GNMS can allow easier harvesting of cells from the microspheres, requiring only 10 ​min of low-temperature treatment and 5 ​min of trypsin treatment. The developed GNMS was characterized by Fourier-transform infrared spectroscopy, optical microscopy, and scanning electron microscopy. Further, live/dead staining, F-actin staining, and PrestoBlue cell viability assays were used to evaluate cytotoxicity, cell morphology, cell proliferation, and harvest efficiency. The gene expression of stem cell markers was determined by real-time quantitative PCR (Q-PCR) analysis to investigate the stemness and phenotypic changes in Wharton's jelly-derived mesenchymal stem cells. The results showed that the engineered cell-laden thermosensitive GNMS could significantly increase the cell harvest rate with over 99% cell survival rate and no change in the cell phenotype. Thus, the described strategy GNMS could be the suitable 3D cell carriers in the therapeutic application and opens new avenues for regenerative medicine.

The Production of Fat-Containing Cultured Meat by Stacking Aligned Muscle Layers and Adipose Layers Formed From Gelatin-Soymilk Scaffold

Tissue engineered cultured meat has been proposed as an emerging innovative process for meat production to overcome the severe consequences of livestock farming, climate change, and an increasing global population. However, currently, cultured meat lacks organized tissue structure, possesses insufficient fat content, and incurs high production costs, which are the major ongoing challenges. In this study, a developed scaffold was synthesized using gelatin and soymilk to create a friendly environment for myogenesis and adipogenesis in C2C12 and 3T3-L1 cells, respectively. The fat containing cultured meat was fabricated with an aligned muscle-like layer and adipose-like layer by stacking these layers alternately. The muscle-like layer expressing myosin and the adipose-like layer abundant in fat were sandwiched to form fat containing muscle tissue. The cytotoxicity and cell survival rate were evaluated using the WST-1 assay and live/dead staining. Myogenesis was confirmed by the expression of myogenin and myosin. The myotubes, myofibrils, and sarcomeres were observed under an inverted microscope, fluorescence microscope, and scanning electron microscope. Adipogenesis was evaluated by protein expression of the peroxisome proliferator-activated receptor γ, and oil droplet accumulation was determined by fluorescence microscopy with Nile Red stain. Extracellular matrix secretion was examined by safranin-O staining. In this study, the cultured meat was prepared with muscle-like texture with the addition of pre-adipocyte, where the multilayered muscle-like tissues with fat content would produce juicy cultured meat.

The Synthesis of Europium-Doped Calcium Carbonate by an Eco-Method as Free Radical Generator Under Low-Intensity Ultrasonic Irradiation for Body Sculpture

Body sculpture is a common method to remove excessive fat. The diet and exercise are the first suggestion to keep body shape; however, those are difficult to keep adherence. Ultrasound has been developed for fat ablation; however, it could only serve as the side treatment along with liposuction. In the study, a sonosensitizer of europium-doped calcium carbonate (CaCO₃: Eu) would be synthesized by an eco-method and combined with low-intensity ultrasound for lipolysis. The crystal structure of CaCO₃: Eu was identified by x-ray diffractometer (XRD). The morphology of CaCO₃: Eu was analyzed by scanning electron microscope (SEM). The chemical composition of CaCO₃: Eu was evaluated by energy-dispersed spectrophotometer (EDS) and inductively coupled plasma mass spectrometer (ICP-MS). The electronic diffraction pattern was to further check crystal structure of the synthesized individual grain by transmission electron microscope (TEM). The particle size was determined by Zeta-sizer. Water-soluble tetrazolium salt (WST-1) were used to evaluate the cell viability. Chloromethyl-2′,7′-dichlorofluorescein diacetate (CM-H₂DCFDA) and live/dead stain were used to evaluate feasibility in vitro. SD-rat was used to evaluate the safety and efficacy in vivo. The results showed that CaCO₃: Eu had good biocompatibility and could produce reactive oxygen species (ROS) after treated with low-intensity ultrasound. After 4-weeks, the CaCO₃: Eu exposed to ultrasound irradiation on SD rats could significantly decrease body weight, waistline, and subcutaneous adipose tissue. We believe that ROS from sonoluminescence, CO₂-bomb and locally increasing Ca²⁺ level would be three major mechanisms to remove away adipo-tissue and inhibit adipogenesis. We could say that the combination of the CaCO₃: Eu and low-intensity ultrasound would be a non-invasive treatment for the body sculpture.

Synthesis, characterization, and evaluation of BDDE crosslinked chitosan-TGA hydrogel encapsulated with genistein for vaginal atrophy

Vagina atrophy is a common symptom in women after menopause owing to decreasing estrogen levels. The most conventional treatment for this condition is estrogen cream. The shortcoming is its weak adhesion to the vagina mucus, thus requiring frequent daily application. In this study, BDDE was selected to crosslink and graft chitosan with thioglycolic acid, to form thiolated chitosan (CT) and improve the mucoadhesive properties of chitosan. Genistein was selected as the bioactive molecule that could exhibit estrogen-like properties for long-term treatment of vaginal atrophy. The efficacies of the materials were characterized and evaluated both in vitro and in vivo. Results showed that the mucoadhesive property of CT was approximately two-fold stronger against the constant flow than unmodified chitosan. CT with genistein (CT-G) was administered intravaginally every three days in vivo. It showed that the developed CT-G recover 54 % of the epithelium thickness of an atrophic vagina and ease vaginal atrophy.

Using C-doped TiO2 Nanoparticles as a Novel Sonosensitizer for Cancer Treatment

Sonodynamic therapy is an effective treatment for eliminating tumor cells by irradiating sonosentitizer in a patient's body with higher penetration ultrasound and inducing the free radicals. Titanium dioxide has attracted the most attention due to its properties among many nanosensitizers. Hence, in this study, carbon doped titanium dioxide, one of inorganic materials, is applied to avoid the foregoing, and furthermore, carbon doped titanium dioxide is used to generate ROS under ultrasound irradiation to eliminate tumor cells. Spherical carbon doped titanium dioxide nanoparticles are synthesized by the sol-gel process. The forming of C-Ti-O bond may also induce defects in lattice which would be beneficial for the phenomenon of sonoluminescence to improve the effectiveness of sonodynamic therapy. By dint of DCFDA, WST-1, LDH and the Live/Dead test, carbon doped titanium dioxide nanoparticles are shown to be a biocompatible material which may induce ROS radicals to suppress the proliferation of 4T1 breast cancer cells under ultrasound treatment. From in vivo study, carbon doped titanium dioxide nanoparticles activated by ultrasound may inhibit the growth of the 4T1 tumor, and it showed a significant difference between sonodynamic therapy (SDT) and the other groups on the seventh day of the treatment.

The preparation of oxidized methylcellulose crosslinked by adipic acid dihydrazide loaded with vitamin C for traumatic brain injury

Oxi-MC-ADH-VC can open up a new avenue for clinical TBI treatment and rehabilitation.

Requirement of the JIP1 scaffold protein for stress-induced JNK activation

The c-Jun N-terminal kinase (JNK) signal transduction pathway is activated in response to the exposure of cells to environmental stress. Components of the JNK signaling pathway interact with the JIP1 scaffold protein. JIP1 is located in the neurites of primary hippocampal neurons. However, in response to stress, JIP1 accumulates in the soma together with activated JNK and phosphorylated c-Jun. Disruption of the Jip1 gene in mice by homologous recombination prevented JNK activation caused by exposure to excitotoxic stress and anoxic stress in vivo and in vitro. These data show that the JIP1 scaffold protein is a critical component of a MAP-kinase signal transduction pathway.

Programmed cell death of developing mammalian neurons after genetic deletion of caspases

An analysis of programmed cell death of several populations of developing postmitotic neurons after genetic deletion of two key members of the caspase family of pro-apoptotic proteases, caspase-3 and caspase-9, indicates that normal neuronal loss occurs. Although the amount of cell death is not altered, the death process may be delayed, and the cells appear to use a nonapoptotic pathway of degeneration. The neuronal populations examined include spinal interneurons and motor, sensory, and autonomic neurons. When examined at both the light and electron microscopic levels, the caspase-deficient neurons exhibit a nonapoptotic morphology in which nuclear changes such as chromatin condensation are absent or reduced; in addition, this morphology is characterized by extensive cytoplasmic vacuolization that is rarely observed in degenerating control neurons. There is also reduced terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling in dying caspase-deficient neurons. Despite the altered morphology and apparent temporal delay in cell death, the number of neurons that are ultimately lost is indistinguishable from that seen in control animals. In contrast to the striking perturbations in the morphology of the forebrain of caspase-deficient embryos, the spinal cord and brainstem appear normal. These results are consistent with the growing idea that the involvement of specific caspases and the occurrence of caspase-independent programmed cell death may be dependent on brain region, cell type, age, and species or may be the result of specific perturbations or pathology.

JNK3 contributes to c-Jun activation and apoptosis but not oxidative stress in nerve growth factor-deprived sympathetic neurons

The stress activated protein kinase pathway culminates in c-Jun phosphorylation mediated by the Jun Kinases (JNKs). The role of the JNK pathway in sympathetic neuronal death is unclear in that apoptosis is not inhibited by a dominant negative protein of one JNK kinase, SEK1, but is inhibited by CEP-1347, a compound known to inhibit this overall pathway but not JNKs per se. To evaluate directly the apoptotic role of the JNK isoform that is selectively expressed in neurons, JNK3, we isolated sympathetic neurons from JNK3-deficient mice and quantified nerve growth factor (NGF) deprivation-induced neuronal death, oxidative stress, c-Jun phosphorylation, and c-jun induction. Here, we report that oxidative stress in neurons from JNK3-deficient mice is normal after NGF deprivation. In contrast, NGF-deprivation-induced increases in the levels of phosphorylated c-Jun, c-jun, and apoptosis are each inhibited in JNK3-deficient mice. Overall, these results indicate that JNK3 plays a critical role in activation of c-Jun and apoptosis in a classic model of cell-autonomous programmed neuron death.

Mechanisms of programmed cell death in the developing brain

Programmed cell death (apoptosis) is an important mechanism that determines the size and shape of the vertebrate nervous system. Recent gene-targeting studies have indicated that homologs of the cell-death pathway in the nematode Caenorhabditis elegans have analogous functions in apoptosis in the developing mammalian brain. However, epistatic genetic analysis has revealed that the apoptosis of progenitor cells during early embryonic development and apoptosis of postmitotic neurons at later stage of brain development have distinct roles and mechanisms. These results provide new insight on the significance and mechanism of neural cell death in mammalian brain development.

Caspase-3 is required for apoptosis-associated DNA fragmentation but not for cell death in neurons deprived of potassium

Caspases are crucial effectors of the cell death pathway activated by virtually all apoptosis-inducing stimuli within neurons and nonneuronal cells. Among the caspases, caspase-3 (CPP32) appears to play a pivotal role and has been found to be necessary for developmentally regulated cell death in the brain. We have used mice lacking caspase-3 (-/-CPP32) to examine its involvement in cultured cerebellar granule neurons induced to undergo apoptosis by potassium deprivation (K+). We find that, following K+ deprivation, neurons from -/-CPP32 mice die to the same extent as those from normal (+/+) mice. Although a small delay in the induction of cell death is observed in -/-CPP32 neurons, the rate of cell death is generally comparable to that of +/+ cultures. Though not critical for neuronal death, caspase-3 is required for DNA fragmentation and chromatin condensation as judged by the absence of these apoptotic features in -/-CPP32 neurons. Boc.Asp.fmk, a pan caspase inhibitor, partially protects +/+ neurons from low-K+-mediated cell death and does so to the same extent in -/-CPP32 cultures, suggesting the involvement of a caspase other than caspase-3 in cell death. However, the protective effect of boc.Asp.fmk is not seen beyond 24 hr, suggesting that the effect of caspase inhibition is one of delaying rather than preventing apoptosis. The more selective caspase inhibitors DEVD.fmk, IETD.fmk, and VEID.fmk fail to affect cell death, indicating that members inhibited by these agents (such as caspases - 6 ,7, 8, 9 and 10) are also not involved in low-K+-mediated apoptosis.

The role of cell death in regulating the size and shape of the mammalian forebrain

The size of the cerebral cortex is determined by the rate of production of neurons and glial cells in the proliferative ventricular and subventricular zones. Recent studies from targeted mutations of different death-effector gene families indicate that programmed cell death (PCD) plays an important role in cell production and early morphogenesis of the mammalian forebrain before the formation of neuronal connections. For example, disruption of the c/Jun N-kinase signaling pathway by double-targeted mutation of both Jnk1 and Jnk2 results in increased PCD in the forebrain leading to precocious degeneration of cerebral precursors. In contrast, disturbance of the caspase cascade by targeted disruption of either casp-9 or casp-3 leads to decreased PCD causing expansion and exencephaly of the forebrain as well as supernumerary neurons in the cerebral cortex. The supernumerary neurons in these knockout mice align radially and form an expanded cortical plate which begins to form cerebral convolutions. Thus, the precise coordination of different apoptotic signaling pathways during early stages of neurogenesis is crucial for regulation of the proper cortical size and shape.

The Jnk1 and Jnk2 protein kinases are required for regional specific apoptosis during early brain development

The c-Jun NH2-terminal kinase (Jnk) family is implicated in apoptosis, but its function in brain development is unclear. Here, we address this issue using mutant mice lacking different members of the family (Jnk1, Jnk2, and Jnk3). Mice deficient in Jnk1, Jnk2, Jnk3, and Jnk1/Jnk3 or Jnk2/Jnk3 double mutants all survived normally. Compound mutants lacking Jnk1 and Jnk2 genes were embryonic lethal and had severe dysregulation of apoptosis in brain. Specifically, there was a reduction of cell death in the lateral edges of hindbrain prior to neural tube closure. In contrast, increased apoptosis and caspase activation were found in the mutant forebrain, leading to precocious degeneration. These results suggest that Jnk1 and Jnk2 regulate region-specific apoptosis during early brain development.

Reduced apoptosis and cytochrome c-mediated caspase activation in mice lacking caspase 9

Caspases are essential components of the mammalian cell death machinery. Here we test the hypothesis that Caspase 9 (Casp9) is a critical upstream activator of caspases through gene targeting in mice. The majority of Casp9 knockout mice die perinatally with a markedly enlarged and malformed cerebrum caused by reduced apoptosis during brain development. Casp9 deletion prevents activation of Casp3 in embryonic brains in vivo, and Casp9-deficient thymocytes show resistance to a subset of apoptotic stimuli, including absence of Casp3-like cleavage and delayed DNA fragmentation. Moreover, the cytochrome c-mediated cleavage of Casp3 is absent in the cytosolic extracts of Casp9-deficient cells but is restored after addition of in vitro-translated Casp9. Together, these results indicate that Casp9 is a critical upstream activator of the caspase cascade in vivo.

Bioflavonoids commonly and potently induce tyrosine dephosphorylation/inactivation of oncogenic proline-directed protein kinase FA in human prostate carcinoma cells

In this study, we investigate the effect of bioflavonoids on the activity and phosphotyrosine content of oncogenic proline-directed protein kinase FA (PDPK FA) in human prostate carcinoma cells. Chronic treatment of human prostate carcinoma cells with low concentrations of quercetin, apigenin, and kaempferol commonly and potently induced tyrosine dephosphorylation and concurrent inactivated oncogenic PDPK FA in a concentration-dependent manner. This is demonstrated by a specific assay of this kinase's activity in the immunoprecipitates from the cell extracts followed by immunoblotting and phosphotyrosine analysis. The results indicate that bioflavonoids may function as common tyrosine kinase inhibitors to inhibit PDPK FA-specific tyrosine kinase and thereby to induce tyrosine dephosphorylation/inactivation of this oncogenic kinase in human carcinoma cells. Under this condition, quercetin, apigenin, and kaempferol can also inhibit cell growth in a similar concentration-dependent manner. The results further indicate that inhibition of tyrosine phosphorylation/activation of this oncogenic PDPK represents a new mode of action mechanism for bioflavonoids during the antiproliferation process in human carcinoma cells.

The naturally occurring PKC inhibitor sphingosine and tumor promoter phorbol ester potentially induce tyrosine phosphorylation/activation of oncogenic proline-directed protein kinase FA/GSK-3alpha in a common signalling pathway

When serum-starved A431 cells were treated with 200 nM phorbol ester TPA for 15 min, the cellular activity of protein kinase FA/glycogen synthase kinase-3alpha (kinase FA/GSK-3alpha) could be decreased to approximately 25% of control. Conversely, when treated with 1 microM TPA for 24 hr, the activity could be reversibly increased to approximately 200% of Control. The naturally occurring protein kinase C (PKC) inhibitor sphingosine at a concentration of 27 microM could also induce activation of kinase FA/GSK-3alpha to approximately 200% of control within 60 min. Further, when cells were chronically treated with 1 microM TPA for 24 hr and then with 27 microM sphingosine for 60 min, the activity of kinase FA/GSK-3alpha could only be increased to approximately 200% of control. Furthermore, when cells were pretreated with sphingosine and then acutely treated with TPA, the acute TPA effect on kinase FA/GSK-3alpha activity could be abolished by genistein or tyrosine phosphorylation, which could be blocked by genistein or tyrosine phosphatase, but could be reversed by orthovanadate. Taken together, the results demonstrate that TPA/sphingosine induce tyrosine phosphorylation and concurrent activation of kinase FA/GSK-3alpha in a common signalling pathway. Since TPA and sphingosine are potent PKC modulators, the results further suggest a potential role of PKC in modulating tyrosine phosphorylation/activation of kinase FA/GSK-3alpha. Kinetic studies on seven subtypes of PKC further demonstrate a specific involvement of PKCE in this tyrosine phosphorylation/activation process. This provides a new mode of signal transduction between these two important serine/threonine kinases in cells.

Absence of excitotoxicity-induced apoptosis in the hippocampus of mice lacking the Jnk3 gene

Excitatory amino acids induce both acute membrane depolarization and latent cellular toxicity, which often leads to apoptosis in many neurological disorders. Recent studies indicate that glutamate toxicity may involve the c-Jun amino-terminal kinase (JNK) group of mitogen-activated protein (MAP) kinases. One member of the JNK family, Jnk3, may be required for stress-induced neuronal apoptosis, as it is selectively expressed in the nervous system. Here we report that disruption of the gene encoding Jnk3 in mice caused the mice to be resistant to the excitotoxic glutamate-receptor agonist kainic acid: they showed a reduction in seizure activity and hippocampal neuron apoptosis was prevented. Although application of kainic acid imposed the same level of noxious stress, the phosphorylation of c-Jun and the transcriptional activity of the AP-1 transcription factor complex were markedly reduced in the mutant mice. These data indicate that the observed neuroprotection is due to the extinction of a Jnk3-mediated signalling pathway, which is an important component in the pathogenesis of glutamate neurotoxicity.

Restrictive clonal allocation in the chimeric mouse brain

Whether, and to what extent, lineage restriction contributes to the organization of the mammalian brain remains unclear. Here we address this issue by examining the distribution of clonally related cells in chimeric mice generated by injecting genetically tagged embryonic stem (ES) cells into blastocyst embryos. Our examination of postnatal chimeric brains revealed that the vast majority of labeled ES cell descendents were confined within a different subset of brain regions in each animal. Moreover, the deployment of labeled cells in different brain regions was distinctive. The pattern of ordered and binomial colonization suggested that early diversified founder cells may constrain the fates of their descendants through a restriction of dispersion. In addition, the symmetrical distribution of ES cell descendants suggests that bilaterally corresponding structures may arise from a common set of progenitor cells. Finally, clones of cells formed a continuous band within the deep strata of the neocortex. This later finding in conjunction with the radial distribution of clones in remaining layers observed in previous studies indicates that the cerebral neocortex may derive from two groups of founder cells, which is consistent with the hypothesis of dual phylogenetic origins of the mammalian cerebral cortex.

Overexpression of protein kinase FA/GSK-3 alpha (a proline-directed protein kinase) correlates with human hepatoma dedifferentiation/progression

Computer analysis of protein phosphorylation sites sequence revealed that transcriptional factors and viral oncoproteins are prime targets for regulation of proline-directed protein phosphorylation, suggesting an association of the proline-directed protein kinase (PDPK) family with neoplastic transformation and tumorigenesis. In this report, an immunoprecipitate activity assay of protein kinase FA/glycogen synthase kinase-3 alpha (kinase F(A)/GSK-3 alpha) (a member of PDPK family) has been optimized for human hepatoma and used to demonstrate for the first time significantly increased (P < 0.01) activity in poorly differentiated SK-Hep-1 hepatoma (24.2 +/- 2.8 units/mg) and moderately differentiated Mahlavu hepatoma (14.5 +/- 2.2 units/mg) when compared to well differentiated Hep 3B hepatoma (8.0 +/- 2.4 units/mg). Immunoblotting analysis revealed that increased activity of kinase FA/GSK-3 alpha is due to overexpression of the protein. Elevated kinase FA/GSK-3 alpha expression in human hepatoma biopsies relative to normal liver tissue was found to be even more profound. This kinase appeared to be fivefold overexpressed in well differentiated hepatoma and 13-fold overexpressed in poorly differentiated hepatoma when compared to normal liver tissue. Taken together, the results provide initial evidence that overexpression of kinase FA/GSK-3 alpha is involved in human hepatoma dedifferentiation/progression. Since kinase FA/GSK-3 alpha is a PDPK, the results further support a potential role of this kinase in human liver tumorigenesis, especially in its dedifferentiation/progression.