Depinning of domain walls in permalloy nanowires with asymmetric notches

Effective control of the domain wall (DW) motion along the magnetic nanowires is of great importance for fundamental research and potential application in spintronic devices. In this work, a series of permalloy nanowires with an asymmetric notch in the middle were fabricated with only varying the width (d) of the right arm from 200 nm to 1000 nm. The detailed pinning and depinning processes of DWs in these nanowires have been studied by using focused magneto-optic Kerr effect (FMOKE) magnetometer, magnetic force microscopy (MFM) and micromagnetic simulation. The experimental results unambiguously exhibit the presence of a DW pinned at the notch in a typical sample with d equal to 500 nm. At a certain range of 200 nm < d < 500 nm, both the experimental and simulated results show that the DW can maintain or change its chirality randomly during passing through the notch, resulting in two DW depinning fields. Those two depinning fields have opposite d dependences, which may be originated from different potential well/barrier generated by the asymmetric notch with varying d.

[Effects of pelvic balance after posterior reduction of balanced L5-S1 Ⅲ-grade isthmic spondylolisthesis in adults]

OBJECTIVE

To observe the changes in pelvic balance after posterior reduction of balanced L5-S1 Ⅲ-grade isthmic spondylolisthesis in adults.

METHODS

A total of 18 adult patients with balanced L5-S1 Ⅲ-grade isthmic spondylolisthesis were retrospectively studied after successful treatment by posterior decompression, reduction and L5-S1 interbody fusion in Department of Orthopedic Surgery, the First Affiliated Hospital of Soochow University from October 2009 to October 2014.L5-S1 of eight patients were fixed with pedical strews, while others were fixed upgrade to L4.Spino-pelvic parameters: slipping percentage (SP), spondy slip angle (SSA), pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT) and lumbar lordosis (LL) were measured on standing lateral view radiograms.The changes in pelvic balance were analyzed after posterior reduction.

RESULTS

All the patients experienced significant changes in SP and SSA with (42.4%±8.3)% and (9.8±4.9)°improved significantly while no significant differences were recorded in PI, PT, SS and LL. PI, PT, SS and LL passed from an average(61.1±6.2)°, (16.2±4.5)°, (44.8±2.9)°, (51.3±9.3)°preoperatively to (61.4±6.1)°, (14.9±4.0)°, (46.5±3.0)°, (48.6±7.0)°respectively.According to K-means cluster analysis, pelvic balance improved postoperatively.No significant correlation was found for ΔPT, ΔSS with ΔSP, while ΔPT and ΔSS had a significant correlation with ΔSSA (correlation coefficient -0.77 and 0.82 respectively).

CONCLUSION

Posterior SSA reduction in adults with balanced L5-S1 Ⅲ-grade isthmic spondylolisthesis can improve the former pelvic balance.

Comparison of two methods for RNA extraction from the nucleus pulposus of intervertebral discs

RNA extraction from the nucleus pulposus of intervertebral discs has been extensively used in orthopedic studies. We compared two methods for extracting RNA from the nucleus pulposus: liquid nitrogen grinding and enzyme digestion. The RNA was detected by agarose gel electrophoresis, and the purity was evaluated by absorbance ratio using a spectrophotometer. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) expression was assayed by reverse transcription-polymerase chain reaction (RT-PCR). Thirty human lumbar intervertebral discs were used in this study. The liquid nitrogen-grinding method was used for RNA extraction from 15 samples, and the mean RNA concentration was 491.04 ± 44.16 ng/mL. The enzyme digestion method was used on 15 samples, and the mean RNA concentration was 898.42 ± 38.64 ng/mL. The statistical analysis revealed that there was a significant difference in concentration between the different methods. Apparent 28S, 18S, and 5S bands were detectable in RNA extracted using the enzyme digestion method, whereas no 28S or 18S bands were detected in RNA extracted using the liquid nitrogen-grinding method. The GAPDH band was visible, and no non-specific band was detected in the RT-PCR assay by the enzyme digestion method. Therefore, the enzyme digestion method is an efficient and easy method for RNA extraction from the nucleus pulposus of intervertebral discs for further intervertebral disc degeneration-related studies.

Hericium erinaceus Inhibits TNF-α-Induced Angiogenesis and ROS Generation through Suppression of MMP-9/NF-κB Signaling and Activation of Nrf2-Mediated Antioxidant Genes in Human EA.hy926 Endothelial Cells

Hericium erinaceus (HE) is an edible mushroom that has been shown to exhibit anticancer and anti-inflammatory activities. We investigated the antiangiogenic and antioxidant potentials of ethanol extracts of HE in human endothelial (EA.hy926) cells upon tumor necrosis factor-α- (TNF-α-) stimulation (10 ng/mL). The underlying molecular mechanisms behind the pharmacological efficacies were elucidated. We found that noncytotoxic concentrations of HE (50-200 μg/mL) significantly inhibited TNF-α-induced migration/invasion and capillary-like tube formation of endothelial cells. HE treatment suppressed TNF-α-induced activity and/or overexpression of matrix metalloproteinase-9 (MMP-9) and intercellular adhesion molecule-1 (ICAM-1). Furthermore, HE downregulated TNF-α-induced nuclear translocation and transcriptional activation of nuclear factor-κB (NF-κB) followed by suppression of I-κB (inhibitor-κB) degradation. Data from fluorescence microscopy illustrated that increased intracellular ROS production upon TNF-α-stimulation was remarkably inhibited by HE pretreatment in a dose-dependent manner. Notably, HE triggered antioxidant gene expressions of heme oxygenase-1 (HO-1), γ-glutamylcysteine synthetase (γ-GCLC), and glutathione levels, which may contribute to inhibition of ROS. Increased antioxidant status was associated with upregulated nuclear translocation and transcriptional activation of NF-E2 related factor-2 (Nrf2) in HE treated cells. Our findings conclude that antiangiogenic and anti-inflammatory activities of H. erinaceus may contribute to its anticancer property through modulation of MMP-9/NF-κB and Nrf2-antioxidant signaling pathways.

Pure spin-Hall magnetoresistance in Rh/Y3Fe5O12 hybrid

We report an investigation of anisotropic magnetoresistance (AMR) and anomalous Hall resistance (AHR) of Rh and Pt thin films sputtered on epitaxial Y₃Fe₅O₁₂ (YIG) ferromagnetic insulator films. For the Pt/YIG hybrid, large spin-Hall magne toresistance (SMR) along with a sizable conventional anisotropic magnetoresistance (CAMR) and a nontrivial temperature dependence of AHR were observed in the temperature range of 5–300 K. In contrast, a reduced SMR with negligible CAMR and AHR was found in Rh/YIG hybrid. Since CAMR and AHR are characteristics for all ferromagnetic metals, our results suggest that the Pt is likely magnetized by YIG due to the magnetic proximity effect (MPE) while Rh remains free of MPE. Thus the Rh/YIG hybrid could be an ideal model system to explore physics and devices associated with pure spin current.

Dermato-protective properties of ergothioneine through induction of Nrf2/ARE-mediated antioxidant genes in UVA-irradiated Human keratinocytes

UVA irradiation-induced skin damage and redox imbalance have been shown to be ameliorated by ergothioneine (EGT), a naturally occurring sulfur-containing amino acid. However, the responsible molecular mechanism with nanomolar concentrations of EGT remains unclear. We investigated the dermato protective efficacies of EGT (125-500nM) against UVA irradiation (15J/cm(2)), and elucidated the underlying molecular mechanism in human keratinocyte-derived HaCaT cells. We found that EGT treatment prior to UVA exposure significantly increased the cell viability and prevented lactate dehydrogenase release into the medium. UVA-induced ROS and comet-like DNA formation were remarkably suppressed by EGT with a parallel inhibition of apoptosis, as evidenced by reduced DNA fragmentation (TUNEL), caspase-9/-3 activation, and Bcl-2/Bax dysregulation. Furthermore, EGT alleviated UVA-induced mitochondrial dysfunction. Dose-dependent increases of antioxidant genes, HO-1, NQO-1, and γ-GCLC and glutathione by EGT were associated with upregulated Nrf2 and downregulated Keap-1 expressions. This was confirmed by increased nuclear accumulation of Nrf2 and inhibition of Nrf2 degradation. Notably, augmented luciferase activity of ARE may explain Nrf2/ARE-mediated signaling pathways behind EGT dermato-protective properties. We further demonstrated that Nrf2 translocation was mediated by PI3K/AKT, PKC, or ROS signaling cascades. This phenomenon was confirmed with suppressed nuclear Nrf2 activation, and consequently diminished antioxidant genes in cells treated with respective pharmacological inhibitors (LY294002, GF109203X, and N-acetylcysteine). Besides, increased basal ROS by EGT appears to be crucial for triggering the Nrf2/ARE signaling pathways. Silencing of Nrf2 or OCTN1 (EGT carrier protein) signaling with siRNA showed no such protective effects of EGT against UVA-induced cell death, ROS, and apoptosis, which is evidence of the vitality of Nrf2 translocation and protective efficacy of EGT in keratinocytes. Our findings conclude that EGT at nanomolar concentrations effectively ameliorated UVA-induced skin damage, and may be considered as a desirable food supplement for skin protection and/or preparation of skin care products.

DAMGO depresses inhibitory synaptic transmission via different downstream pathways of μ opioid receptors in ventral tegmental area and periaqueductal gray

Opioid-induced rewarding and motorstimulant effects are mediated by an increased activity of the ventral tegmental area (VTA) dopamine (DA) neurons. The excitatory mechanism of opioids on VTA-DA neurons has been proposed to be due to the depression of GABAergic synaptic transmission in VTA-DA neurons. However, how opioids depress GABAergic synaptic transmission in VTA-DA neurons remain to be studied. In the present study, we explored the mechanism of the inhibitory effect of [D-Ala(2), N-Me-Phe(4), Gly(5)-ol]-enkephalin (DAMGO) on GABAergic synaptic transmission in VTA-DA neurons using multiple approaches and techniques. Our results showed that (1) DAMGO inhibits GABAergic inputs in VTA-DA neurons at presynaptic sites; (2) effect of DAMGO on GABAergic inputs in VTA-DA neurons is inhibited by potassium channel blocker 4-aminopyridine (4-AP) and Gi protein inhibitor N-ethylmaleimide (NEM); (3) phospholipase A2 (PLA2) does not mediate the effect of DAMGO on GABAergic inputs in VTA-DA neurons, but mediates it in the periaqueductal gray (PAG); (4) multiple downstream signaling molecules of μ receptors do not mediate the effect of DAMGO on GABAergic inputs in VTA-DA neurons. These results suggest that DAMGO depresses inhibitory synaptic transmission via μ receptor-Gi protein-Kv channel pathway in VTA-DA neurons, but via μ receptor-PLA2 pathway in PAG neurons.

Isolation of microsatellite loci for Rhodiola alsia (Crassulaceae), an important ethno-medicinal herb endemic to the Qinghai-Tibetan plateau

Rhodiola alsia, which has been used widely in traditional Chinese medicine for a considerable time, grows on moist habitats at high altitude near the snow line. Microsatellite loci were developed for R. alsia to investigate its population genetics. In total, 17 polymorphic microsatellites were developed based on ESTs from the Illumina HiSeq(TM) 2000 platform. The microsatellite loci were checked for variability using 80 individuals of R. alsia sampled from four locations on the Qinghai-Tibet Plateau. The total number of alleles per locus ranged from 10 to 20, and the observed heterozygosity ranged from 0.000 to 1.000. The null allele frequency ranged from 0.000 to 0.324. These microsatellites are expected to be helpful in future studies of population genetics in R. alsia and related species.

VAV3 oncogene expression in colorectal cancer: clinical aspects and functional characterization

Although colorectal cancer (CRC) is one of the most common malignancies worldwide, the current therapeutic approaches for advanced CRC are ineffective. In this study, we investigated the involvement of the VAV3 oncogene in tumor progression and in the prognosis of human CRC. The two patient cohorts in this study comprised 354 CRC cases from 1998 to 2005 with documented pathologic and clinical factors and clinical outcomes. VAV3 protein levels were significantly correlated with the depth of invasion (P = 0.0259), the nodal status (P < 0.0001), distant metastasis (P = 0.0354), the stage (P < 0.0001), and poor disease-free survival (P = 0.003). Multivariate Cox regression analysis showed that VAV3 overexpression is an independent prognostic marker for CRC (P = 0.041). In vitro experiments indicated that VAV3 knockdown inhibited CRC cell growth, spread, and xenograft proliferation. Mechanistic studies further revealed that VAV3 overexpression could dysregulate the expression of cell cycle control- and metastasis-related molecules by activating the PI3K-AKT signaling pathway in both CRC cells and xenografts. This study suggests that VAV3 overexpression could be a useful marker for predicting the outcomes of CRC patients and that VAV3 targeting represents a potential modality for treating CRC.

Induction of macrophage cell-cycle arrest and apoptosis by humic acid

Humic acid (HA) in well water is associated with Blackfoot disease and various cancers. Previously, we reported that acute humic acid exposure (25-200 µg/mL for 24 hr) induces inflammation in RAW264.7 macrophages. In this study, we observed that prolonged (72 hr) HA exposure (25-200 µg/mL) induces cell-cycle arrest and apoptosis in cultured RAW264.7 cells. We also observed that exposing macrophages to HA arrests cells in the G2 /M phase of the cell cycle by reducing cyclin A/B1 , Cdc2, and Cdc25C levels. Treating macrophages with HA triggers a sequence of events characteristic of apoptotic cell death including loss of cell viability, morphological changes, internucleosomal DNA fragmentation, sub-G1 accumulation. Molecular markers of apoptosis associated with mitochondrial dysfunction were similarly observed, including cytochrome c release, caspase-3 or caspase-9 activation, and Bcl-2/Bax dysregulation. In addition to the mitochondrial pathway, HA-induced apoptosis may also be mediated through the death receptor and ER stress pathways, as evidence by induction of Fas, caspase-8, caspase-4, and caspase-12 activity. HA also upregulates p53 expression and causes DNA damage as assessed by the comet assay. These findings yield new insight into the mechanisms by which HA exposure may trigger atherosclerosis through modulation of the macrophage-mediated immune system.

Induction of Nrf2-mediated genes by Antrodia salmonea inhibits ROS generation and inflammatory effects in lipopolysaccharide-stimulated RAW264.7 macrophages

Antrodia salmonea (AS), a well-known medicinal mushroom in Taiwan, has been reported to exhibit anti-oxidant, anti-angiogenic, anti-atherogenic, and anti-inflammatory effects. In the present study, we investigated the activation of Nrf2-mediated antioxidant genes in RAW264.7 macrophages by the fermented culture broth of AS, studied the resulting protection against lipopolysaccharide (LPS)-stimulated inflammation, and revealed the molecular mechanisms underlying these protective effects. We found that non-cytotoxic concentrations of AS (25-100 μg mL⁻¹) protected macrophages from LPS-induced cell death and ROS generation in a dose-dependent manner. The antioxidant potential of AS was directly correlated with the increased expression of the antioxidant genes HO-1, NQO-1, and γ-GCLC, as well as the level of intracellular GSH followed by an increase in the nuclear translocation and transcriptional activation of the Nrf2-ARE pathway. Furthermore, Nrf2 knockdown diminished the protective effects of AS, as evidenced by the increased production of pro-inflammatory cytokines and chemokines, including PGE₂, NO, TNF-α, and IL-1β, in LPS-stimulated macrophages. Notably, AS treatment significantly inhibited LPS-induced ICAM-1 expression in macrophages. Our data suggest that the anti-inflammatory potential of Antrodia salmonea is mediated by the activation of Nrf2-dependent antioxidant defense mechanisms. Results support the traditional usage of this beneficial mushroom for the treatment of free radical-related diseases and inflammation.

Penta-O-galloyl-β-D-glucose suppresses EGF-induced eIF3i expression through inhibition of the PI3K/AKT/mTOR pathway in prostate cancer cells

Approximately 70% of prostate cancer patients will develop bone metastasis in axial and other regions of the skeleton. Epidermal growth factor (EGF) generated from bone tissue contributes to prostate cancer metastasis. In a previous study, penta-O-galloyl-β-D-glucose (PGG) suppressed androgen-independent prostate cancer bone metastasis by transcriptionally repressing EGF-induced MMP-9 expression. This study utilized proteomics to analyze the effects of PGG in EGF-induced prostate cancer bone metastasis. This study showed that PGG suppressed EGF-induced eIF3i expression in PC-3 cells. By transfection of eIF3i shRNA, it was observed that reduced eIF3i expression suppressed the invasion of PC-3 cells in vitro. PGG reduced EGF-induced eIF3i expression through inhibition of the PI3K/AKT/mTOR pathway. Therefore, PGG may be able to be used as a potential new therapeutic drug for prostate cancer bone metastasis.

The anti-tumor activity of Antrodia salmonea in human promyelocytic leukemia (HL-60) cells is mediated via the induction of G₁ cell-cycle arrest and apoptosis in vitro or in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

The medicinal mushroom Antrodia salmonea has been used as a traditional Chinese medicine and has demonstrated antioxidant and anti-inflammatory effects.

MATERIALS AND METHODS

In the present study, we examined the anti-tumor activity of the fermented culture broth of Antrodia salmonea (AS) in vitro and in vivo and revealed its underlying molecular mechanism of action.

RESULTS

Treatment of human promyelocytic leukemia (HL-60) cells with AS (50-150 μg/mL) significantly reduced cell viability and caused G1 arrest via the inhibition of cell-cycle regulatory proteins, including cyclin D1, CDK4, cyclin E, cyclin A, and phosphorylated retinoblastoma protein (p-Rb). Furthermore, AS treatment induced apoptosis, which was associated with DNA fragmentation, followed by a sequence of events, including intracellular ROS generation; mitochondrial dysfunction; Fas ligand activation; cytochrome c release; caspase-3, -8, -9, and PARP activation; and Bcl-2/Bax dysregulation. The results of the in vitro study suggested that AS-induced apoptosis in HL-60 cells was mediated by both the mitochondrial and death receptor pathways. Furthermore, we found that AS treatment was effective in delaying tumor incidence in HL-60 xenografted nude mice and reducing tumor burden.

CONCLUSIONS

To the best of our knowledge, this is the first report confirming the anti-tumor activity of this potentially beneficial mushroom against human promyelocytic leukemia.

Long-term effects of evodiamine on expressions of lipogenesis and lipolysis genes in mouse adipose and liver tissues

Evodiamine, the major alkaloid component isolated from the fruit of dried, unripened Evodia rutaecarpa Bentham, affects the plasma levels of cholecystokinin and various biological events such as gastric emptying and gastrointestinal transit; these effects of evodiamine were previously investigated in male rats. In this study, we aimed to investigate the effects of evodiamine on average daily weight gain, rectal temperature, and expressions of genes involved in lipid metabolism in liver and adipose tissues. Evodiamine was added as a supplement, comprising 0.02, 0.04, and 0.06% of the diet fed to mice for 1, 2, 3, and 4 weeks. Results showed that average daily weight gain and rectal temperature decreased significantly over time in a dose-dependent manner. Evodiamine changed expressions of the peroxisome proliferator-activated receptor-g (PPARg) in mouse adipose and liver tissues in time- and dose-dependent manners. We found that evodiamine decreased mRNA expression of the sterol-regulatory element binding protein (SREBP-1c) and fatty acid synthase in adipose tissue. In addition, evodiamine increased expressions of hormone-sensitive lipase in both liver and adipose tissues. Interestingly, evodiamine increased the expression of triglyceride hydrolase only in adipose tissue. In conclusion, evodiamine could influence lipid metabolism through regulation of the expressions of its key genes, as well as reduce body heat and body weight.

Antrodia camphorata induces G1 cell-cycle arrest in human premyelocytic leukemia (HL-60) cells and suppresses tumor growth in athymic nude mice

Antrodia camphorata is a well-known medicinal mushroom in Taiwan.

Antrodia salmonea inhibits TNF-α-induced angiogenesis and atherogenesis in human endothelial cells through the down-regulation of NF-κB and up-regulation of Nrf2 signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Antrodia salmonea (AS) is known as a traditional Chinese medicine, but very few biological activities have been reported.

MATERIALS AND METHODS

The present study was aimed to investigate the anti-angiogenic and anti-atherosclerotic potential of the fermented culture broth of AS against tumor necrosis factor-α (TNF-α)-stimulated human endothelial (EA.hy 926) cells.

RESULTS

The non-cytotoxic concentrations of AS significantly inhibited TNF-α-induced migration/invasion and capillary-like tube formation in EA.hy 926 cells. Furthermore, AS suppressed TNF-α-induced activity and expression of matrix metalloproteinase-9 (MMP-9), and cell-surface expression of intercellular adhesion molecule-1 (ICAM-1), which was associated with abridged adhesion of U937 leukocytes to endothelial cells. Moreover, AS significantly down-regulated TNF-α-induced nuclear translocation and transcriptional activation of nuclear factor κB (NF-κB) followed by suppression of I-κB degradation and phosphorylation of I-κB kinase-α (IKKα). Notably, the protective effect of AS was directly correlated with the increased expression of hemeoxygenase-1 (HO-1) and γ-glutamylcysteine synthetase (γ-GCLC), which was reasoned by nuclear translocation and transactivation of NF-E2 related factor-2 (Nrf2)/antioxidant response element (ARE). Furthermore, HO-1 knockdown by HO-1-specific shRNA diminished the protective effects of AS on TNF-α-stimulated invasion, tube formation, and U937 adhesion in EA.hy 926 cells.

CONCLUSIONS

Taken together, these results suggest that Antrodia salmonea may be useful for the prevention of angiogenesis and atherosclerosis.

Cardenolides and bufadienolide glycosides from Kalanchoe tubiflora and evaluation of cytotoxicity

Two new cardenolides, kalantubolide A (1) and kalantubolide B (2), and two bufadienolide glycosides, kalantuboside A (3) and kalantuboside B (4), as well as eleven known compounds were isolated and characterized from the EtOH extract of Kalanchoe tubiflora. The structures of compounds were assigned based on 1D and 2D NMR spectroscopic analyses including HMQC, HMBC, and NOESY. Biological evaluation indicated that cardenolides (1-2) and bufadienolide glycosides (3-7) showed strong cytotoxicity against four human tumor cell lines (A549, Cal-27, A2058, and HL-60) with IC50 values ranging from 0.01 µM to 10.66 µM. Cardenolides (1-2) also displayed significant cytotoxicity toward HL-60 tumor cell line. In addition, compounds 3, 4, 5, 6, and 7 blocked the cell cycle in the G2/M-phase and induced apoptosis in HL-60 cells.

The anti-cancer activity of Antrodia camphorata against human ovarian carcinoma (SKOV-3) cells via modulation of HER-2/neu signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Antrodia camphorata (AC) is well known in Taiwan as a traditional Chinese medicinal fungus. However, the anticancer activity of AC against human HER-2/neu-overexpressing ovarian cancers is poorly understood.

MATERIALS AND METHODS

The aim of this study is to investigate whether a submerged fermentation culture of AC can inhibit human ovarian carcinoma cell (SKOV-3) proliferation by suppressing the HER-2/neu signaling pathway. Cell viability, colony formation, DCFH-DA fluorescence microscopy, western blotting, HER-2/neu immunofluorescence imaging, flow cytometry, and TUNEL assays were carried out to determine the anti-cancer effects of AC.

RESULTS

MTT and colony formation assays showed that AC induced a dose-dependent reduction in SKOV-3 cell growth. Immunoblot analysis demonstrated that HER-2/neu activity and tyrosine phosphorylation were significantly inhibited by AC. Furthermore, AC treatment significantly inhibited the activation of PI3K/Akt and their downstream effector β-catenin. We also observed that AC caused G2/M arrest mediated by down-regulation of cyclin D1, cyclin A, cyclin B1, and Cdk1 and increased p27 expression. Notably, AC induced apoptosis, which was associated with DNA fragmentation, cytochrome c release, caspase-9/-3 activation, PARP degradation, and Bcl-2/Bax dysregulation. An increase in intracellular reactive oxygen species (ROS) was observed in AC-treated cells, whereas the antioxidant N-acetylcysteine (NAC) prevented AC-induced cell death, HER-2/neu depletion, PI3K/Akt inactivation, and Bcl-2/Bax dysregulation, indicating that AC-induced cell death was mediated by ROS generation.

CONCLUSIONS

These results suggest that AC may exert anti-tumor activity against human ovarian carcinoma by suppressing HER-2/neu signaling pathways.

Lucidone protects human skin keratinocytes against free radical-induced oxidative damage and inflammation through the up-regulation of HO-1/Nrf2 antioxidant genes and down-regulation of NF-κB signaling pathway

We investigated the protective effects of lucidone, a naturally occurring cyclopentenedione isolated from the fruits of Lindera erythrocarpa Makino, against free-radical and inflammation stimulator 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH)-induced oxidative stress in human keratinocyte (HaCaT) cells, with the aim of revealing the possible mechanisms underlying the protective efficacy. Lucidone pretreatment (0.5-10 μg/mL) markedly increased HaCaT cell viability and suppressed AAPH-induced reactive oxygen species (ROS) generation, lipid peroxidation, and DNA damage. Notably, the antioxidant potential of lucidone was directly correlated with the increased expression of an antioxidant gene, heme oxygenase 1 (HO-1), which was followed by the augmentation of the nuclear translocation and transcriptional activation of NF-E2-related factor-2 (Nrf2), with or without AAPH. Nrf2 knockdown diminished the protective effects of lucidone. We also observed that lucidone pretreatment inhibited AAPH-induced inflammatory chemokine prostaglandin E₂ (PGE₂) production and the expression of cyclooxygenase-2 (COX-2) in HaCaT cells. Lucidone treatment also significantly inhibited AAPH-induced nuclear factor-κB (NF-κB) activation and suppressing the degradation of inhibitor-κB (I-κB). Furthermore, lucidone significantly diminished AAPH-induced COX-2 expression through the down-regulation of the extracellular signal-regulated kinase (ERK) and p38 MAPK signaling pathways. Therefore, lucidone may possess antioxidant and anti-inflammatory properties and may be useful for the prevention of free radical-induced skin damage.

Differential expression of lipid metabolism genes in the liver and adipose tissue of mice treated with evodiamine

Evodiamine is the main active alkali of Wu Zhuyu, a widely distributed Chinese herb. It plays an important role in the regulation of body fat deposition. In this study, we aimed to investigate the effect of evodiamine administration on the expression of genes involved in lipid metabolism in the liver and adipose tissue. Fasted mice were subcutaneously injected with evodiamine (37 °C, 20 mg/kg), and the core body temperature change and expression levels of lipid metabolism-related genes were evaluated at baseline, 0.5, 1, and 2 h. We detected the mRNA expression of fatty acid synthesis enzyme (FAS), peroxisome proliferator-activated receptor gamma (PPAR-γ), sterol regulatory element binding protein 1c (SREBP-1c), triglyceride hydrolase (TGH), and hormone-sensitive lipase (HSL) by real-time PCR and analyzed their correlation with core body temperature. Our results showed that the core body temperature was reduced greater than 1 °C with evodiamine treatment at 1 and 2 h (P < 0.01). In mouse livers, SREBP-1c, HSL, and TGH mRNA expression was significantly increased, and they reached the highest levels 1 h after injection (P < 0.01). However, PPAR-γ mRNA expression was decreased and reached a significant level at 0.5 h (P < 0.01) and FAS mRNA expression was not significantly different; FAS and SREBP-1c mRNA expression were reduced and reached significant levels at 1 h (P < 0.01). Of note, other genes demonstrated opposite changes in adipose tissue, and HSL mRNA expression was significantly reduced at 0.5 h (P < 0.01). The decreasing core temperature had a significant negative correlation with the expression of TGH, HSL, FAS, and SREBP- 1c mRNA in the liver (P < 0.01), but had significant positive correlation with levels of FAS and SREBP-1c mRNA in adipose tissue (P < 0.01). In light of these results, the main mechanism of the regulation of body fat deposition by evodiamine is raising energy consumption through reducing body temperature and promoting fat decomposition.

In vitro and in vivo studies disclosed the depigmenting effects of gallic acid: a novel skin lightening agent for hyperpigmentary skin diseases

Gallic acid (GA) is a phenolic compound, which has been reported to suppress melanogenesis in melanoma cells. However, the molecular mechanism underlying this inhibitory effect was poorly understood. In this article, we revealed that GA down-regulated melanogenic regulatory genes including tyrosinase, tyrosinase related protein-1 (TRP-1), and dopachrome tatamerase (Dct) expression at transcriptional and translational level. In addition, GA effectively suppressed the microphthalmia-associated transcription factor (MITF) expression by down-regulating the cAMP-mediated PKA/CREB signaling cascades. To delineate the inhibition of MITF by GA, the activation of extracellular signal-regulated protein kinase (ERK) and AKT was investigated. GA caused significant increase of ERK and AKT phosphorylation, while ERK (PD98059) or AKT (LY294002) inhibitor prevents their phosphorylation and increased melanin biosynthesis. In addition, pre-treatment of MITF-siRNA significantly reduced melanin production from 100 to 40%, and even decreased into 10% by combination treatment with GA. Furthermore, UVB-induced hyperpigmentation in the mice skin was significantly rescued by topical application of GA for 4 weeks. Immunohistochemical analyses also confirmed that GA significantly inhibited melanin production followed by the down-regulation of MITF, tyrosinase and their regulatory proteins. In addition, when compared with control zebrafish, GA caused a remarkable inhibition on the endogenous pigmentation in the zebrafish. Results presented in this study strongly suggest that GA is an effective de-pigmenting or skin lightening cosmetics for topical application.

Construction of suppressor of cytokine signaling 2 (SOCS2) adenoviral overexpression vector and its impact on growth-hormone-induced lipolysis in swine primary adipocytes

We investigated the effect of overexpression suppressor of cytokine signaling 2 (SOCS2) on lipolysis in swine primary adipocytes (pAd) induced by growth hormone (GH). We constructed pAd-SOCS2 adenoviral overexpression vectors to infect HEK293 cells for virus packaging and propagation. Cultured swine primary adipocytes were infected with virus particles; after 48 h the infected adipocytes were treated with 500 ng GH/mL in the growth medium. Lipometabolism-related gene expressions were detected at 0, 0.25, 0.5, 1, 2, and 4 h, by measuring mRNA and protein levels. The pAd-SOCS2 overexpression vector was successfully constructed and the concentration of titrated virus was 1.2 x 10(9) PFU/mL. We found that virus infection significantly increased SOCS2 mRNA and protein levels in swine primary adipocytes. Overexpression of SOCS2 significantly inhibited the increase in fatty acid synthase, adipose triglyceride lipase mRNA, and protein expression at 0.5 h. However, after 0.5 h, this inhibition was not significant. We concluded that overexpression of SOCS2 inhibited the increase in lipolysis induced by GH in swine primary adipocytes; this could provide a basis for studies of lipometabolism.