Mitochondrial Dysfunction as an Underlying Cause of Skeletal Muscle Disorders.

Mitochondria are an important energy source in skeletal muscle. A main function of mitochondria is the generation of ATP for energy through oxidative phosphorylation (OXPHOS). Mitochondrial defects or abnormalities can lead to muscle disease or multisystem disease.

Identification of distinct slow mode of reversible adaptation of pancreatic ductal adenocarcinoma to the prolonged acidic pH microenvironment.

Background: Pancreatic ductal adenocarcinoma (PDAC) is the most common pancreatic neoplasm with high metastatic potential and poor clinical outcome. Like other solid tumors, PDAC in the early stages is often asymptomatic, and grows very slowly under a distinct acidic pHe (extracellular pH) microenvironment. However, most previous studies have only reported the fate of cancerous cells upon cursory exposure to acidic pHe conditions.

Conditioned Media of Adipose-Derived Stem Cells Suppresses Sidestream Cigarette Smoke Extract Induced Cell Death and Epithelial-Mesenchymal Transition in Lung Epithelial Cells.

The role of the epithelial-mesenchymal transition (EMT) in lung epithelial cells is increasingly being recognized as a key stage in the development of COPD, fibrosis, and lung cancers, which are all highly associated with cigarette smoking and with exposure to second-hand smoke. Using the exposure of human lung cancer epithelial A549 cells and non-cancerous Beas-2B cells to sidestream cigarette smoke extract (CSE) as a model, we studied the protective effects of adipose-derived stem cell-conditioned medium (ADSC-CM) against CSE-induced cell death and EMT. CSE dose-dependently induced cell death, decreased epithelial markers, and increased the expression of mesenchymal markers.

Enhancement of Neurite Outgrowth by Warming Biomaterial Ultrasound Treatment.

Ultrasound is a method for enhancing neurite outgrowth because of its thermal effect. In order to reach the working temperature to enhance neurite outgrowth, long-time treatment by ultrasound is necessary, while acknowledging that the treatment poses a high risk of damaging nerve cells. To overcome this problem, we developed a method that shortens the ultrasonic treatment time with a warming biomaterial.

A Tri-fusion Reporter Mouse Reveals Tissue-Specific FGF1B Promoter Activity in vivo.

Transgenic mice harboring imaging reporters take full advantage of imaging technologies in studies using living mice. Here, we established a tri-fusion multimodal reporter gene containing fragments from firefly luciferase, enhanced green fluorescent protein, and herpes simplex virus type 1 thymidine kinase and generated tri-fusion reporter Tg mice. Fibroblast growth factor type 1 (FGF1), a multifunctional mitogen to a wide range of tissues, regulates proliferation of neural stem cells of the brain, where FGF1 expression is initiated through activation of the FGF1B (F1B) promoter.

Cardiac fibrosis in mouse expressing DsRed tetramers involves chronic autophagy and proteasome degradation insufficiency.

Proteinopathy in the heart which often manifests excessive misfolded/aggregated proteins in cardiac myocytes can result in severe fibrosis and heart failure. Here we developed a mouse model, which transgenically express tetrameric DsRed, a red fluorescent protein (RFP), in an attempt to mimic the pathological mechanisms ofcardiac fibrosis. Whilst DsRed is expressed and forms aggregation in most mouse organs, certain pathological defects are specifically recapitulated in cardiac muscle cells including mitochondria damages, aggresome-like residual bodies, excessive ubiquitinated proteins, and the induction of autophagy.

Neonatal Death and Heart Failure in Mouse with Transgenic HSP60 Expression.

Mitochondrial heat shock proteins, such as HSP60, are chaperones responsible for the folding, transport, and quality control of mitochondrial matrix proteins and are essential for maintaining life. Both prosurvival and proapoptotic roles have been proposed for HSP60, and HSP60 is reportedly involved in the initiation of autoimmune, metabolic, and cardiovascular diseases. The role of HSP60 in pathogenesis of these diseases remains unclear, partly because of the lack of mouse models expressing HSP60.

Notch signaling prevents mucous metaplasia in mouse conducting airways during postnatal development.

Goblet cell metaplasia and mucus overproduction contribute to the pathogenesis of chronic lung diseases, including asthma and chronic obstructive pulmonary disease (COPD). Notch signaling regulates cell fate decisions and is crucial in controlling goblet cell differentiation in the gut epithelium. Little is known, however, about how endogenous Notch signaling influences the goblet cell differentiation program that takes place in the postnatal lung.

A single-monomer derived linear-like PEI-co-PEG for siRNA delivery and silencing.

Polyethylenimines (PEIs) are commonly used as a vehicle to deliver and protect siRNA, but the strong interaction still remains to be modulated for efficient siRNA release and silencing. Herein, a single-monomer derived linear-like PEI-co-PEG (LPEI-co-PEG, P(2)) was synthesized to substantially enhance the siRNA release, but not affect the efficiency of protection. The linear-like copolymer (P(2)) was only synthesized from a single-monomer by intensive synchrotron X-ray irradiation within 5 min, randomly producing both PEI and PEG segments.

Notch signaling regulates late-stage epidermal differentiation and maintains postnatal hair cycle homeostasis.

Background: Notch signaling involves ligand-receptor interactions through direct cell-cell contact. Multiple Notch receptors and ligands are expressed in the epidermis and hair follicles during embryonic development and the adult stage. Although Notch signaling plays an important role in regulating differentiation of the epidermis and hair follicles, it remains unclear how Notch signaling participates in late-stage epidermal differentiation and postnatal hair cycle homeostasis.

RU486-inducible recombination in the salivary glands of lactoferrin promoter-driven green fluorescent Cre transgenic mice.

When compared with the many tamoxifen-activated Cre mouse lines available for gene manipulation studies, relatively few RU486-inducible Cre mice are in use, due to leakiness issues. Here, we report the generation of an RU486-inducible triple fusion gene (GCrePR1e), consisting of green fluorescent protein, Cre, and the progesterone receptor ligand-binding domain (F642-L901). We sought to improve the GCrePR1e by selecting a truncated human lactoferrin (Lf) promoter to drive its expression, based on the promoter's low basal activity and innate sensitivity to RU486.

Mechanical strain modulates age-related changes in the proliferation and differentiation of mouse adipose-derived stromal cells.

Background: Previous studies on the effects of aging in human and mouse mesenchymal stem cells suggest that a decline in the number and differentiation potential of stem cells may contribute to aging and aging-related diseases. In this report, we used stromal cells isolated from adipose tissue (ADSCs) of young (8-10 weeks), adult (5 months), and old (21 months) mice to test the hypothesis that mechanical loading modifies aging-related changes in the self-renewal and osteogenic and adipogenic differentiation potential of these cells.

Results: We show that aging significantly reduced the proliferation and increased the adipogenesis of ADSCs, while the osteogenic potential is not significantly reduced by aging.

Mechanical stretching induces osteoprotegerin in differentiating C2C12 precursor cells through noncanonical Wnt pathways.

Mechanical loading is known to be important for maintaining the formation and resorption rates of bone. To study the mechanisms by which mechanical loading regulates osteogenesis, we investigated the role of the Wnt pathway in C2C12 cells committed to osteogenic differentiation in response to cyclic mechanical stretching. Osteoprotegerin (OPG) acts as a decoy receptor for RANKL to inhibit osteoclastogenesis and resorption of bone.

Detection of experimentally induced pulmonary granuloma inflammation in monocyte chemoattractant protein-1 reporter mice.

Purpose: Among different chemokines, monocyte chemoattractant protein-1 (MCP-1) plays an important role in inflammatory disorders of lung. In response to stimuli, MCP-1 increases its transcription as an immediate early gene. In this paper, we describe the MCP-1-enhanced green fluorescent protein(EGFP) transgenic mouse in which EGFP expression is driven by human MCP-1 promoter and mimics the MCP-1 expression in situ.

The use of injectable spherically symmetric cell aggregates self-assembled in a thermo-responsive hydrogel for enhanced cell transplantation.

Typical cell transplantation techniques involve the administration of dissociated cells directly injected into muscular tissues; however, retention of the transplanted cells at the sites of the cell graft is frequently limited. An approach, using spherically symmetric aggregates of cells with a relatively uniform size self-assembled in a thermo-responsive methylcellulose hydrogel system, is reported in the study. The obtained cell aggregates preserved their endogenous extracellular matrices (ECM) and intercellular junctions because no proteolytic enzyme was used when harvesting the cell aggregates.

Multi-ion-crosslinked nanoparticles with pH-responsive characteristics for oral delivery of protein drugs.

pH-Responsive nanoparticles composed of chitosan (CS) and poly-gamma-glutamic acid (gamma-PGA) blended with tripolyphosphate (TPP) and MgSO(4) (multi-ion-crosslinked NPs) were prepared and characterized to determine their effectiveness in the oral delivery of insulin. Their counterparts without TPP and MgSO(4) (NPs) were used as a control. FT-IR and XRD results indicated that the spontaneous interaction between CS, insulin, gamma-PGA, MgSO(4) and TPP can form an ionically crosslinked network-structure, leading to the formation of nanoparticles.

Human breast tumor cells express multimodal imaging reporter genes.

Objective: Human ZR75-1 cells were among the first few characterized estrogen-dependent mammary gland carcinoma cell lines and had been utilized in various studies for the pro- or antitumor effect of xenoestrogens and antiestrogens. The objective of this study was to establish a breast tumor model in ZR75-1 cells bearing multimodal reporter genes to allow noninvasive imaging of tumor growth using fluorescence and nuclear imaging platforms.

Methods And Results: Enhanced green fluorescent protein (eGFP) cDNA was fused at the C-terminus with herpes simplex virus type 1 thymidine kinase (HSV1-tk) to form the fusion reporter gene (eGFP-tk).

Angiogenic evaluation of ginsenoside Rg 1 from Panax ginseng in fluorescent transgenic mice.

Background: Evaluation of angiogenesis-inducing compounds is essential in tissue engineering to develop biological substitutes for the repair or regeneration of tissue function. In this report, we evaluated the angiogenic ability of ginsenoside Rg 1 from Panax ginseng, in Matrigel implanted on fluorescent transgenic mice.

Methods: The in vitro proliferation ability of each test agent was estimated by MTS assay.

Stability of angiogenic agents, ginsenoside Rg1 and Re, isolated from Panax ginseng: in vitro and in vivo studies.

The study was designed to investigate the stability of ginsenoside Rg(1) (Rg(1)) and Re (Re), two natural herbal compounds isolated from Panax ginseng, based on their activity to promote angiogenesis in vitro and in vivo. After being treated at different temperatures, pHs, and solvent species for distinct durations, the remaining activities of Rg(1) and Re on human umbilical vein endothelial cell (HUVEC) proliferation, migration, and tube formation were examined in vitro. Additionally, the remaining activity of each treated test agent, mixed in a growth factor-reduced Matrigel, in stimulating angiogenesis was evaluated subcutaneously in a mouse model.

Shear stress regulates gene expression in vascular endothelial cells in response to tumor necrosis factor-alpha: a study of the transcription profile with complementary DNA microarray.

We investigate the role of shear stress in regulating the gene expression in endothelial cells (ECs) in response to tumor necrosis factor-alpha (TNF-alpha). ECs were kept in static condition or pre-exposed to a high level (HSS, 20 dynes/cm2) or a low level of shear stress (LSS, 0.5 dynes/cm2) for 24 h, and TNF-alpha was added under static condition for 4 h.

Myocyte protection by 10 kD heat shock protein (Hsp10) involves the mobile loop and attenuation of the Ras GTP-ase pathway.

Heat shock proteins (hsp), hsp60 and hsp10, are involved in the folding of imported mitochondrial proteins and the refolding of denatured proteins after stress. We examined whether hsp10 can reduce myocyte death by its mitochondrial function or by interacting with cytoplasmic signaling pathways. Overexpression of hsp10 by adenoviral infection decreased myocyte death induced by hydrogen peroxide, sodium cyanide, and simulated ischemia and reoxygenation (SI/RO).

Overexpression of PHGPx and HSP60/10 protects against ischemia/reoxygenation injury.

Reactive oxygen species arising from ischemia/reperfusion (I/R) cause damage to cardiac tissue. We examined the effects of mitochondrial phospholipid hydroperoxide glutathione peroxidase (mPHGPx) and cytosolic PHGPx (cPHGPx) overexpression on protection against simulated I/R in neonatal rat cardiac myocytes (NCM). Additionally, a protective combinatorial effect with heat shock proteins 60 and 10 (HSP60/10) was investigated.