An Experimental Model Design for Photoaging.

Unlabelled: Autologous adipose-derived stem cells have shown great promise in applications that treat photodamaged skin. Adipose-derived stem cells also have an antiwrinkle effect; consequently, they have become a topic of primary interest. Nude mice have been used extensively in studies of adipose-derived stem cells, human dermal fibroblasts, and other filler injections.

Improvement of photoaged skin wrinkles with cultured human fibroblasts and adipose-derived stem cells: a comparative study.

We investigated the antiwrinkle effects of cultured human fibroblasts and adipose-derived stem cells (ADSCs) and the mechanisms underlying the reduction of wrinkles in photoaged skin. The fibroblasts and ADSCs were isolated from human tissue and cultured. A total of 28 6-week-old female BALB/c nude mice were classified into four groups, including the normal control group and three groups that were irradiated six times a week for 6-weeks using ultraviolet B radiation to induce photoaged wrinkles.

Tiam-1, a GEF for Rac1, plays a critical role in metformin-mediated glucose uptake in C2C12 cells.

Metformin is known to stimulate glucose uptake, but the mechanism for this action is not fully understood. In this study, AMPK activators (AICAR and metformin) increased the expression of T-lymphoma invasion and metastasis-inducing protein-1 (Tiam-1), a Rac1 specific guanine nucleotide exchange factor (GEF), mRNA and protein in skeletal muscle C2C12 cells. Metformin increases the serine-phosphorylation of Tiam-1 by AMPK and induces interaction between Tiam-1 and 14-3-3.

E3 ubiquitin ligase, WWP1, interacts with AMPKα2 and down-regulates its expression in skeletal muscle C2C12 cells.

It is known that the activity of AMP-activated protein kinase (AMPKα2) was depressed under high glucose conditions. However, whether protein expression of AMPKα2 is also down-regulated or not remains unclear. In this study, we showed that the expression of AMPKα2 was down-regulated in cells cultured under high glucose conditions.

Celastrol suppresses breast cancer MCF-7 cell viability via the AMP-activated protein kinase (AMPK)-induced p53-polo like kinase 2 (PLK-2) pathway.

Celastrol, an anti-oxidant flavonoid that is widely distributed in the plant kingdom, has been suggested to have chemopreventive effects on cancer cells: however, the mechanism of this process is not completely understood. In this study, we found that celastrol suppressed the viability of breast cancer MCF-7 cells in an AMP-activated protein kinase (AMPK)-dependent fashion. Celastrol also induced an increase in reactive oxygen species (ROS) levels, leading to AMPK phosphorylation.

Metformin regulates glucose transporter 4 (GLUT4) translocation through AMP-activated protein kinase (AMPK)-mediated Cbl/CAP signaling in 3T3-L1 preadipocyte cells.

Metformin is a leading oral anti-diabetes mellitus medication and is known to stimulate GLUT4 translocation. However, the mechanism by which metformin acts is still largely unknown. Here, we showed that short time treatment with metformin rapidly increased phosphorylation of Cbl in an AMP-activated protein kinase (AMPK)-dependent fashion in 3T3-L1 preadipocytes.

Coenzyme Q10 increases the fatty acid oxidation through AMPK-mediated PPARα induction in 3T3-L1 preadipocytes.

Coenzyme Q10(CoQ10) is a known anti-adipogenic factor. However, the mechanism by which CoQ10 acts is unclear. In this study, we found that CoQ10 increased the phosphorylation of AMP-activated protein kinase (AMPK) in 3T3-L1preadipocytes.

Metformin sensitizes insulin signaling through AMPK-mediated PTEN down-regulation in preadipocyte 3T3-L1 cells.

Insulin resistance is the primary cause responsible for type 2 diabetes. Phosphatase and tensin homolog (PTEN) plays a negative role in insulin signaling and its inhibition improves insulin sensitivity. Metformin is a widely used insulin-sensitizing drug; however, the mechanism by which metformin acts is poorly understood.

The glutamate agonist homocysteine sulfinic acid stimulates glucose uptake through the calcium-dependent AMPK-p38 MAPK-protein kinase C zeta pathway in skeletal muscle cells.

Homocysteine sulfinic acid (HCSA) is a homologue of the amino acid cysteine and a selective metabotropic glutamate receptor (mGluR) agonist. However, the metabolic role of HCSA is poorly understood. In this study, we showed that HCSA and glutamate stimulated glucose uptake in C2C12 mouse myoblast cells and increased AMP-activated protein kinase (AMPK) phosphorylation.

Metformin induces Rab4 through AMPK and modulates GLUT4 translocation in skeletal muscle cells.

Metformin is a major oral anti-diabetic drug and is known as an insulin sensitizer. However, the mechanism by which metformin acts is unclear. In this study, we found that AICAR, an AMPK activator, and metformin increased the expression of Rab4 mRNA and protein levels in skeletal muscle C2C12 cells.

Clozapine activates AMP-activated protein kinase (AMPK) in C2C12 myotube cells and stimulates glucose uptake.

Aims: Clozapine has previously been implicated in the dysregulation of energy balance and glucose metabolism in the central nervous system, but its effects in the periphery have yet to be thoroughly elucidated. The objective of this study was to characterize the effects of clozapine on AMP-activated protein kinase (AMPK) activity in the skeletal muscles.

Main Methods: Myotube C2C12 cells were incubated under control conditions, or with clozapine.

C-peptide stimulates nitrites generation via the calcium-JAK2/STAT1 pathway in murine macrophage Raw264.7 cells.

Aims: C-peptide is a product of pro-insulin cleavage. Numerous studies have demonstrated that C-peptide, although not influencing blood glucose control, may play a role in preventing and potentially reversing some of the chronic complications of type 1 diabetes. The aim of this paper was to present a novel function of C-peptide, focusing on its role in nitric oxide (NO) generation.

Curcumin stimulates glucose uptake through AMPK-p38 MAPK pathways in L6 myotube cells.

Curcumin has been shown to exert a variety of beneficial human health effects. However, mechanisms by which curcumin acts are poorly understood. In this study, we report that curcumin activated AMP-activated protein kinase (AMPK) and increased glucose uptake in rat L6 myotubes.

Quercetin suppresses HeLa cell viability via AMPK-induced HSP70 and EGFR down-regulation.

Quercetin, an anti-oxidant flavonoid that is widely distributed in the plant kingdom, has been suggested to have chemopreventive effects on cancer cells, although the mechanism is not completely understood. In this study, we found that quercetin increased the phosphorylation of AMP-activated protein kinase (AMPK) and downstream acetyl-CoA carboxylase (ACC) and suppressed the viability of HeLa cells. AICAR, an AMPK activator, and quercetin down-regulated heat shock protein (HSP)70 and increased the activity of the pro-apoptotic effector, caspase 3.

Gaegurin-6 stimulates insulin secretion through calcium influx in pancreatic beta Rin5mf cells.

Gaegurin-6, an antimicrobial peptide that belongs to the alpha-helix family, was isolated from the skin of Rana rugosa. Gaegurin-6 contains a hydrophobic motif at the N-terminus and a helical region at the C-terminus. Although gaegurin-6 has been implicated in cell signaling, the precise role in insulin secretion is currently unknown.