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Interleukin‐38 (IL‐38), recently recognized as a cytokine with anti‐inflammatory properties that mitigate type 2 diabetes, has been associated with indicators of insulin resistance and nonalcoholic fatty liver disease (NAFLD). This study investigated the impact of IL‐38 on hepatic lipid metabolism and endoplasmic reticulum (ER) stress. We assessed protein expression levels using Western blot analysis, while monodansylcadaverine staining was employed to detect autophagosomes in hepatocytes. Oil red O staining was utilized to examine lipid deposition. The study revealed elevated serum IL‐38 levels in high‐fat diet (HFD)‐fed mice and IL‐38 secretion from mouse keratinocytes. IL‐38 treatment attenuated lipogenic lipid accumulation and ER stress markers in hepatocytes exposed to palmitate. Furthermore, IL‐38 treatment increased AMP‐activated protein kinase (AMPK) phosphorylation and autophagy. The effects of IL‐38 on lipogenic lipid deposition and ER stress were nullified in cultured hepatocytes by suppressing AMPK through small interfering (si) RNA or 3‐methyladenine (3MA). In animal studies, IL‐38 administration mitigated hepatic steatosis by suppressing the expression of lipogenic proteins and ER stress markers while reversing AMPK phosphorylation and autophagy markers in the livers of HFD‐fed mice. Additionally, AMPK siRNA, but not 3MA, mitigated IL‐38‐enhanced fatty acid oxidation in hepatocytes. In summary, IL‐38 alleviates hepatic steatosis through AMPK/autophagy signaling‐dependent attenuation of ER stress and enhancement of fatty acid oxidation via the AMPK pathway, suggesting a therapeutic strategy for treating NAFLD. [ABSTRACT FROM AUTHOR]

This article discusses the role of heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2B1) in the development of myocardial fibrosis (MF), a condition characterized by the excessive accumulation of extracellular matrix in the heart. The study found that hnRNPA2B1 is upregulated in MF and regulates the inflammatory response and activation of cardiac fibroblasts. The researchers identified miR-221-3p/Foxo4 axis as a key pathway regulated by hnRNPA2B1 in MF. Understanding the role of hnRNPA2B1 in cardiac fibrosis could lead to new therapeutic strategies for treating MF. [Extracted from the article]

Present understandings of cardiomyocyte mechanobiology have primarily been developed using 2‐dimensional, monocellular cell cultures, however the emergence of 3‐dimensional (3D) multicellular cardiac constructs has enabled us to develop more sophisticated recapitulations of the cardiac microenvironment. Several of these strategies have illustrated that incorporating elements of the extracellular matrix (ECM) can promote greater maturation and enhance desirable cardiac functions, such as contractility, but the responses of these cardiac constructs to biophysically aberrant conditions, such as in the post‐infarct heart, has remained relatively unexplored. In our study, we employ a stiffness gradient gelatin methacryloyl (GelMA) hydrogel platform to unpack the mechanobiology of cardiac spheroids. We encapsulated neonatal rat cardiac cell spheroids in a 4.4–18.7 kPa linear stiffness gradient up to 120 h. We found the proportion of viable cells within the spheroids increased over time, but the cell number per spheroid decreased. Spheroids expand more in softer matrices while stiffer matrices promote larger nuclei without changing nuclei shape. Volume expansion came primarily from cells expressing vimentin. We did not observe any correlations between stiffness and mechanomarker expression, however we found that after 120 h post‐encapsulation, the localization of YAP, the localization of MRTF‐A and the expression of Lamin‐A was correlated with spheroid morphology. The same trends were not observed 24 h post‐encapsulation, indicating that volume adaptation can take a relatively long time. Our data demonstrates that cardiac spheroids are mechanosensitive and that their capacity to respond to ECM‐based cues depends on their capacity to adapt their volume with a 3D microenvironment. [ABSTRACT FROM AUTHOR]

Gremlin‐1 (GR1) is a novel adipokine that is highly expressed in human adipocytes and has been shown to inhibit the BMP2/4‐TGFb signaling pathway. It has an effect on insulin sensitivity. Elevated levels of Gremlin have been shown to lead to insulin resistance in skeletal muscle, adipocytes, and hepatocytes. In this study, we investigated the effect of GR1 on hepatic lipid metabolism under hyperlipidemic conditions and explored the molecular mechanisms associated with GR1 by in vitro and in vivo studies. We found that palmitate increased GR1 expression in visceral adipocytes. Recombinant GR1 increased lipid accumulation, lipogenesis, and ER stress markers in cultured primary hepatocytes. Treatment with GR1 increased EGFR expression and mTOR phosphorylation and reduced autophagy markers. EGFR or rapamycin siRNA reduced the effects of GR1 on lipogenic lipid deposition and ER stress in cultured hepatocytes. Administration of GR1 via the tail vein induced lipogenic proteins and ER stress while suppressing autophagy in the livers of experimental mice. Suppression of GR1 by in vivo transfection reduced the effects of a high‐fat diet on hepatic lipid metabolism, ER stress, and autophagy in mice. These results suggest that the adipokine GR1 promotes hepatic ER stress due to the impairment of autophagy, ultimately causing hepatic steatosis in the obese state. The current study demonstrated that targeting GR1 may be a potential therapeutic approach for treating metabolic diseases, including metabolic‐associated fatty liver disease (MAFLD). [ABSTRACT FROM AUTHOR]

Recently, sclerostin (SCL), a circulating glycoprotein, was proposed to be a novel myokine involved in developing metabolic disorders. The association between SCL levels and insulin resistance in skeletal muscle, liver, and adipose tissue was studied in individuals with aggravated glucose tolerance. Thus, we hypothesized that elevated circulating SCL might affect skeletal muscle insulin signaling and hepatic lipid metabolism, and aimed to investigate the effects of SCL on skeletal muscle insulin resistance and hepatic steatosis in obesity using in vitro and in vivo experimental models under hyperlipidemic conditions. In the current study, we found elevated SCL messenger RNA expression levels in myocytes in obese patients. In addition to a higher blood level, SCL was expressed at an elevated level in the skeletal muscle of mice fed a high‐fat diet (HFD). Higher SCL release levels and expression were also noticed in palmitate‐treated C2C12 myocytes. SCL suppression by in vivo transfection improves skeletal muscle insulin resistance and hepatic steatosis in HFD‐fed mice. The treatment of C2C12 myocytes with recombinant SCL aggravated insulin signaling. Furthermore, treatment with SCL augmented lipogenic lipid deposition in human primary hepatocytes. Treatment with SCL upregulated mammalian target of rapamycin (mTOR) phosphorylation and suppressed autophagy markers, thereby causing endoplasmic reticulum (ER) stress. 4‐Phenylbutyric acid, a pharmacological ER stress inhibitor, abolished the effects of SCL on insulin signaling in C2C12 myocytes and lipid accumulation in primary hepatocytes. In conclusion, SCL promotes skeletal muscle insulin resistance and hepatic steatosis by upregulating ER stress via the mTOR/autophagy‐mediated pathway. The present study suggests that antagonizing SCL might be a novel therapeutic strategy for simultaneously managing insulin resistance and hepatic steatosis in obesity. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum (ER) stress plays a causative role in the development of nonalcoholic fatty liver disease (NAFLD). Kynurenic acid (KA) is a tryptophan metabolite that has been shown to exert anti‐inflammatory effects in macrophages and endothelial cells. However, the role of KA in ER stress‐associated development of NAFLD has not been fully explored. In the current study, we observed decreased KA levels in the serum of obese subjects. Treated hepatocytes with KA attenuated palmitate‐induced lipid accumulation and downregulated lipogenesis‐associated genes as well as ER stress markers in a dose‐dependent manner. Furthermore, KA augmented AMP‐activated protein kinase (AMPK) phosphorylation, oxygen‐regulated protein 150 (ORP150) expression, and autophagy markers. The small interfering RNA‐mediated suppression of AMPK and ORP150, or 3‐methyladenine also abrogated the effects of KA on ER stress and lipid accumulation in hepatocytes. In accordance with in vitro observations, KA administration to mice fed a high‐fat diet ameliorated hepatic lipid accumulation and decreased the expression of lipogenic genes as well as ER stress. Moreover, KA treatment increased hepatic AMPK phosphorylation, ORP150 expression, and autophagy related markers in mouse livers. Knockdown of AMPK using in vivo transfection mitigated the effects of KA on hepatic steatosis and ER stress as well as autophagy and ORP150 expression. These results suggest that KA ameliorates hepatic steatosis via the AMPK/autophagy‐ and AMPK/ORP150‐mediated suppression of ER stress. In sum, KA might be used as a promising therapeutic agent for treatment of NAFLD. [ABSTRACT FROM AUTHOR]

This work shows that microporous organic polymer can be applied to the engineering of CeO2‐based antioxidant nanomaterials for in vivo regenerative wound healing. Whilst nanoparticulate CeO2 has shown excellent redox quenching of reactive oxygen species (ROS) because it is rich in oxygen defects and Ce3+ species, it has a strong tendency to form aggregates because it is a kinetic intermediate of bulk materials. Anchoring of nanoparticulate CeO2 on suitable supports can be an efficient anti‐aggregation strategy. In this work, CeO2 nanoparticles were immobilized on microporous organic nanoparticles (MONPs) to form MONP@CeO2 nanocomposites. Compared to CeO2 materials, the MONP@CeO2 nanocomposites showed not only efficient ROS scavenging in in vivo regenerative wound healing but also reduced cytotoxicity in in vitro cell studies, due to the efficient distribution and dilution effect of CeO2 nanomaterials. [ABSTRACT FROM AUTHOR]

In the present study, we investigated whether mood stabilizer lithium (Li) protects against d‐amphetamine (AMP)‐induced mania‐like behaviours via modulating the novel proinflammatory potential. Repeated treatment with AMP resulted in significant increases in proinflammatory cyclooxygenase‐2 (COX‐2) and indolemaine‐2,3‐dioxygenase‐1 (IDO)‐1 expression in the prefrontal cortex (PFC) of mice. However, AMP treatment did not significantly change IDO‐2 and 5‐lipoxygenase (5‐LOX) expression, suggesting that proinflammatory parameters such as COX‐2 and IDO‐1 are specific for AMP‐induced behaviours. AMP‐induced initial expression of COX‐2 (15 minutes post‐AMP) was earlier than that of IDO‐1 (1 hour post‐AMP). Mood stabilizer Li and COX‐2 inhibitor meloxicam significantly attenuated COX‐2 expression 15 minutes post‐AMP, whereas IDO‐1 inhibitor 1‐methyl‐DL‐tryptophan (1‐MT) did not affect COX‐2 expression. However, AMP‐induced IDO‐1 expression was significantly attenuated by Li, meloxicam or 1‐MT, suggesting that COX‐2 is an upstream molecule for the induction of IDO‐1 caused by AMP. Consistently, co‐immunoprecipitation between COX‐2 and IDO‐1 was observed at 30 minutes, 1, 3, and 6 hours after the final AMP treatment. This interaction was also significantly inhibited by Li, meloxicam or 1‐MT. Furthermore, AMP‐induced hyperlocomotion was significantly attenuated by Li, meloxicam or 1‐MT. We report, for the first time, that mood stabilizer Li attenuates AMP‐induced mania‐like behaviour via attenuation of interaction between COX‐2 and IDO‐1, and that the interaction of COX‐2 and IDO‐1 may be critical for the therapeutic intervention mediated by mood stabilizer. [ABSTRACT FROM AUTHOR]

It has been reported that asprosin is a novel adipokine which is augmented in mice and humans with type 2 diabetes (T2DM). Asprosin stimulates hepatic gluconeogenesis under fasting conditions. However, the roles of asprosin in inflammation, endoplasmic reticulum (ER) stress, and insulin resistance in skeletal muscle has not been studied. In the currents study, elevated levels of asprosin expression were observed in adipocytes under hyperlipidemic conditions. Treatment of C2C12 myocytes with asprosin‐induced ER stress markers (phosphorylated inositol‐requiring enzyme 1 and eukaryotic initiation factor 2, and CHOP expression) as well as inflammation markers (interleukin‐6 expression, phosphorylated IκB, and nuclear translocated nuclear factor‐κβ). Finally, asprosin treatment promoted exacerbation of insulin sensitivity as determined by levels of insulin receptor substrate 1 and Akt phosphorylation as well as glucose uptake. Moreover, treatment of asprosin augmented protein kinase C‐δ (PKCδ) phosphorylation and nuclear translocation, but suppressed messenger RNA expression of sarcoplasmic reticulum Ca2+ ATPase 2b in both C2C12 myocytes and in mouse soleus skeletal muscle. These asprosin‐induced effects were markedly decreased in small interfering (si) RNA‐mediated PKCδ‐knockdown in C2C12 myocytes. These results suggest that asprosin results in impairment of insulin sensitivity in skeletal muscle through PKCδ‐associated ER stress/inflammation pathways and may be a valuable strategy for management of insulin resistance and T2DM. [ABSTRACT FROM AUTHOR]

The role as well as the molecular mechanisms of protectin DX (PDX) in the prevention of hepatic insulin resistance, a hallmark of type 2 diabetes, remains unknown. Therefore, the present study was designed to explore the direct impact of PDX on insulin resistance and to investigate the expression of fetuin‐A and selenoprotein P (SeP), hepatokines that are involved in insulin signalling, in hepatocytes. Human serum levels of PDX as well as fetuin‐A and SeP were determined by high‐performance liquid chromatography (HPLC). Human primary hepatocytes were treated with palmitate and PDX. NF‐κB phosphorylation as well as expression of insulin signalling associated genes and hepatokines were determined by Western blotting analysis. FOXO1 binding levels were measured by quantitative real‐time PCR. Selected genes from candidate pathways were evaluated by small interfering (si) RNA‐mediated gene suppression. Serum PDX levels were significantly (P < 0.05) downregulated, whereas serum fetuin‐A and SeP levels were increased (P < 0.05) in obese subjects compared with healthy subjects. In in vitro experiments, PDX treatment increased AMP‐activated protein kinase (AMPK) phosphorylation and SIRT1 expression and attenuated palmitate‐induced fetuin‐A and SeP expression and insulin resistance in hepatocytes. AMPK or SIRT1 siRNA mitigated the suppressive effects of PDX on palmitate‐induced fetuin‐A through NF‐κB and SeP expression linked to FOXO1 and insulin resistance. Recombinant fetuin‐A and SeP reversed the suppressive effects of fetuin‐A and SeP expression on palmitate‐mediated impairment of insulin signalling. The current finding provides novel insight into the underlying mechanism linking hepatokines to the pathogenesis of hepatic insulin resistance. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether the glutathione peroxidase‐1 gene (GPx‐1) affects cocaine‐induced conditioned place preference (CPP) using a mouse model. Cocaine‐induced CPP was accompanied by an increase in the level of σ‐1 receptor in the nucleus accumbens (NAc). This phenomenon was more pronounced in the GPx‐1 gene knockout (GPx‐1 KO) than in wild type (WT) mice. In contrast, the CPP and expression of σ‐1 receptor were much less pronounced in GPx‐1‐overexpressing transgenic (GPx‐1 TG) mice than non‐transgenic (non‐TG) mice. Treatment of the mice with BD1047, a σ‐1 receptor antagonist, significantly attenuated both cocaine‐induced CPP and c‐Fos‐immunoreactivity (c‐Fos‐IR) in WT and GPx‐1 KO mice, although the effects were more evident in the latter group. Despite the protective effects of BD1047 on cocaine‐induced CPP and c‐Fos in non‐TG mice, there were no additional protective effects in cocaine‐treated GPx‐1 TG mice, indicating that the σ‐1 receptor is a critical target for GPx‐1‐mediated psychoprotective activity. Overall, our results suggest that GPx‐1 attenuates cocaine‐induced CPP via inhibition of σ‐1 receptor expression. [ABSTRACT FROM AUTHOR]

The role of histone deacetylase 3 (HDAC3) is to repress the expression of various genes by eliminating acetyl group from histone. Thus, the regulation of HDAC3 activity is essential to maintain cellular homeostasis. In this study, we found that HDAC3 interacts with c‐Src kinase. However, the interaction between HDAC3 and c‐Src was previously reported, it has still been ambiguous whether c‐Src phosphorylates HDAC3 and affects the function of HDAC3. First, we confirmed that HDAC3 directly binds to c‐Src, and c‐Src identified to interact with C‐terminal domain (277–428 a.a.) of HDAC3. c‐Src also phosphorylated three tyrosine sites of HDAC3 at tyrosine 325, 328, and 331. Importantly, wild‐type c‐Src increases HDAC3 activity, but not mutant c‐SrcK298M (kinase inactive form). When these tyrosine residues are all substituted for alanine residues, the deacetylase activity of mutant HDAC3 was abolished. In addition, a proliferation of HER2‐positive breast cancer cells expressing phosphorylation deficient mutant HDAC3 is decreased in comparison with control cells. Thus, our findings suggested that phosphorylation of HDAC3 by c‐Src kinase regulates the HDAC3 activity and the proliferation of breast cancer cells. c‐Src phosphorylates HDAC3: Phosphorylation of HDAC3 by c‐Src regulates cancer cell proliferation [ABSTRACT FROM AUTHOR]

Since the cocaine‐induced oxidative stress has been established to lead to hepatotoxicity, we examined the role of the glutathione peroxidase (GPx)‐1 gene in cocaine‐induced hepatotoxicity. Cocaine treatment significantly increased superoxide dismutase activity in as little as 1 hour, with a maximum level at 6 hours in wild‐type mice, while significantly decreasing GPx activity and subsequently inducing oxidative damage (i.e., reactive oxygen species, lipid peroxidation and protein carbonylation). These changes were more prominent in the mitochondrial fraction than in the cytosolic fraction. In contrast, genetic overexpression of GPx‐1 significantly attenuated cocaine‐induced oxidative damage in mice. Cocaine treatment significantly increased alanine aminotransferase and aspartate aminotransferase levels in the serum. Consistently, cocaine significantly enhanced cleaved caspase‐3 expression and intramitochondrial Ca2+, while significantly reducing mitochondrial transmembrane potential. Cocaine treatment potentiated cleavage of protein kinase C δ (PKCδ), mitochondrial translocation of PKCδ, cytosolic release of cytochrome c and activation of caspase‐3, followed by hepatopathologic changes. These results were more prominent in GPx‐1 knockout than in wild‐type mice, and they were less pronounced in overexpressing transgenic than in non‐transgenic mice. Combined, our results suggest that the GPx‐1 gene possesses protective potential against mitochondrial oxidative burden, mitochondrial dysfunction and hepatic degeneration induced by cocaine and that the protective mechanisms are associated with anti‐apoptotic activity via inactivation of PKCδ. We investigated the role of glutathione peroxidase (GPx)‐1, a major subtype of GPx in response to hepatotoxicity induced by cocaine in mice. We observed that the failure in GPx induction against superoxide dismutase activation mediates cocaine hepatotoxicity, suggesting that the endogenous GPx‐1 gene is involved in a defensive mechanism against the hepatotoxicity. Furthermore, we also found that the overexpression of the GPx‐1 gene protects cocaine‐induced hepatotoxicity in mice via attenuating mitochondrial burdens (oxidative stress and dysfunction) and pro‐apoptotic parameters. [ABSTRACT FROM AUTHOR]

Abstract: Although it has been well‐recognized that microcystin‐leucine‐arginine (MCLR), the most common form of microcystins, induces neurotoxicity, little is currently known about the underlying mechanism for this neurotoxicity. Here, we found that MCLR (10 ng/μL/mouse, i.c.v.) induces significant neuronal loss in the hippocampus of mice. MCLR‐induced neurotoxicity was accompanied by oxidative stress, as shown by a significant increase in the level of 4‐hydroxynonenal, protein carbonyl, and reactive oxygen species (ROS). Superoxide dismutase‐1 (SOD‐1) activity was significantly increased, but glutathione peroxidase (GPx) level was significantly decreased following MCLR insult. In addition, MCLR significantly inhibited GSH/GSSG ratio, and significantly induced NFκB DNA binding activity. Because reduced activity of GPx appeared to be critical for the imbalance between activities of SODs and GPx, we utilized GPx‐1 overexpressing transgenic mice to ascertain the role of GPx‐1 in this neurotoxicity. Genetic overexpression of GPx‐1 or NFκB inhibitor pyrrolidine dithiocarbamate (PDTC) significantly attenuated MCLR‐induced hippocampal neuronal loss in mice. However, PDTC did not exert any additive effect on neuroprotection mediated by GPx‐1 overexpression, indicating that NFκB is a neurotoxic target of MCLR. Combined, these results suggest that MCLR‐induced neurotoxicity requires oxidative stress associated with failure in compensatory induction of GPx, possibly through activation of the transcription factor NFκB. [ABSTRACT FROM AUTHOR]

Wnt1‐inducible signaling pathway protein‐1 (WISP1) is a Cyr61/CTGF/NOV (CCN) family matricellular protein involved in adipogenesis and low‐grade inflammation in obesity. However, the roles of WISP1 in hepatic steatosis and insulin resistance in skeletal muscle remain elusive. Mouse primary hepatocytes and differentiated mouse skeletal muscle cells (C2C12) were treated with various concentrations of WISP1 and the functions and signaling pathways were analyzed by Western blot analysis. In vivo transfection for WISP1 knockdown was also performed to examine the effects of WISP1 on hepatic steatosis and skeletal muscle insulin resistance. Knockdown of WISP1 in high‐fat diet‐fed C57BL/6 mice significantly reduced (0.45–0.5%; p < 0.05) inflammation and JNK phosphorylation (45–50%; P < 0.01) and attenuated hepatic steatosis (approximately 55%; p < 0.001) and skeletal muscle insulin resistance (30–40%; p < 0.05). Treatment with WISP1 significantly induced inflammation (hepatocytes: approximately 500%; p < 0.01, C2C12 cells: approximately 500%; p < 0.01) and JNK phosphorylation (hepatocytes: approximately 200%; p < 0.01, C2C12 cells: approximately 280%; p < 0.01) in mouse primary hepatocytes and C2C12 mouse skeletal muscle cells. Moreover, it increased lipogenesis‐associated gene expression (200–300%; p < 0.01) and accumulation of triglycerides (approximately 320%; p < 0.01) in hepatocytes, and suppressed insulin signaling (approximately 50%; p < 0.01) in C2C12 cells. These WISP1‐induced effects were significantly abrogated in NFκB‐, JNK‐, and TLR4‐knockdown hepatocytes (p < 0.05) and C2C12 cells (p < 0.05). These results indicate that WISP1 contributes to hepatic steatosis and skeletal muscle insulin resistance through a TLR4‐activated inflammation/JNK signaling pathway and could be a useful therapeutic target for treatment of non‐alcoholic fatty liver disease and type 2 diabetes. [ABSTRACT FROM AUTHOR]

The category of 'leafy vegetables' comprises a wide range of plants, including cabbage, lettuce, leeks, spinach, Swiss chard and kale, and it forms a significant component of the human diet. Typically, leafy vegetables are low in calories and fat, are great sources of vitamins, protein, dietary fibre and minerals (including iron, calcium, and nitrates), and are rich in phytochemicals. To counter the impact of pests on vegetables, a broad variety of pesticides are used. Because of their large surface areas, leafy vegetables are expected to have high residual pesticide levels. As such, a sound analytical approach is needed to detect and quantify residue levels that are equal to or lower than the maximum residue limits, thus rendering the products safe for consumption. Overall, leafy vegetables consumed raw (after a tap water wash only), boiled or steamed contribute 2% of total vegetable consumption globally, and they might have a comparatively greater influence on health than cereal ingestion. Consequently, in this review paper, we highlight the importance of leafy vegetables, the pesticides that are commonly used on them and various analytical techniques, including sample preparation, extraction, clean-up and final detection. The effects on dissipation patterns, pre-harvest residue limits and safety/risks imposed by various pesticides are also reviewed and discussed. In conclusion, environmentally friendly extraction methods coupled with high-throughput techniques with greater reproducibility and lower uncertainty are needed for quantifying residues in leafy vegetables at very low concentrations. Commercial and household food preparation, such as washing, peeling, blanching and cooking are effective in removing most of the pesticide residues that are loosely attached on vegetables. [ABSTRACT FROM AUTHOR]

The Korean Petasites japonicus is a perennial plant used in folk medicine as a remedy for many diseases and popularly consumed as spring greens. Ten polyphenols were characterized from the leaves, stems and roots of this plant via high-performance liquid chromatography-tandem mass spectrometry. Individual polyphenols were quantified for the first time using calibration curves of six structurally related external standards. Validation data indicated that coefficients of determinations ( R2) were ≥0.9702 for all standards. Recoveries measured at 50 and 100 mg/L were 80.0-91.9 and 80.3-105.3%, respectively. Precisions at these two concentration levels were 0.7-6.1 and 1.1-5.5%, respectively. The total number of identified components was largest for the leaves and smallest for the stems. The leaf and root polyphenolic extracts showed anti-inflammatory effects by inducing LPS-activated COX-2 and iNOS protein levels in mouse macrophage RAW 264.7 cells. The antioxidant capacity of the polyphenols, when evaluated for DPPH ( α, α-diphenyl- β-picrylhydrazyl)ˑ, ABTS+ [2-2′-azino- bis(3-ethylbenzothiazoline-6-sulfonic acid)] and superoxide radical scavenging activities, and in ferric reducing ability of plasma (FRAP) assays, was highest in the leaf and lowest in the stem. This trend suggests that the antioxidant capacities depend primarily on polyphenol concentration in each tissue. The current findings suggest that polyphenols derived from P. japonica s tissues could have potential as functional health foods. [ABSTRACT FROM AUTHOR]

Despite their potential in various fields of bioapplications, such as drug/cell delivery, tissue engineering, and regenerative medicine, hydrogels have often suffered from their weak mechanical properties, which are attributed to their single network of polymers. Here, supertough composite hydrogels are proposed consisting of alginate/polyacrylamide double-network hydrogels embedded with mesoporous silica particles (SBA-15). The supertoughness is derived from efficient energy dissipation through the multiple bondings, such as ionic crosslinking of alginate, covalent crosslinking of polyacrylamide, and van der Waals interactions and hydrogen bondings between SBA-15 and the polymers. The superior mechanical properties of these hybrid hydrogels make it possible to maintain the hydrogel structure for a long period of time in a physiological solution. Based on their high mechanical stability, these hybrid hydrogels are demonstrated to exhibit on-demand drug release, which is controlled by an external mechanical stimulation (both in vitro and in vivo). Moreover, different types of drugs can be separately loaded into the hydrogel network and mesopores of SBA-15 and can be released with different speeds, suggesting that these hydrogels can also be used for multiple drug release. [ABSTRACT FROM AUTHOR]

The present study investigates the role of the glutathione peroxidase ( GPx)-1 gene in cocaine-induced renal damage in mice. Multiple doses of cocaine increased lipid peroxidation, protein oxidation, and glutathione oxidation in the kidney of the non-transgenic mice (non- TG mice). The enzymatic activities of GPx and glutathione reductase were significantly decreased in non- TG mice, whereas superoxide dismutase was increased in the early phase of cocaine exposure. Treatment with cocaine resulted in significant decreases in expression of Bcl-2 and Bcl-xl in the kidney of non- TG mice, which resulted in significant increases in Bax and cleaved-caspase 3. Consistently, cocaine-induced tubular epithelial vacuolization and focal tubular necrosis were mainly observed in the proximal tubules in the kidneys of non- TG mice. These renal pathologic changes were much less pronounced in GPx-1 TG than in non- TG mice. These results suggest that the GPx-1 gene is a protective factor against nephrotoxicity induced by cocaine via interactive modulations between antioxidant and cell survival signaling processes. [ABSTRACT FROM AUTHOR]

Recently, we have demonstrated that ginsenoside Re protects methamphetamine (MA)-induced dopaminergic toxicity in mice via genetic inhibition of PKCδ and attenuation of mitochondrial stress. In addition, we have reported that induction of mitochondrial glutathione peroxidase (GPx) is also important for neuroprotection mediated by ginsenoside Re. To extend our knowledge, we examined the effects of ginsenoside Re against MA toxicity in vitro condition using SH-SY5Y neuroblastoma cells. Treatment with ginsenoside Re resulted in significant attenuations against a decrease in the activity of GPx and an increase in the activity of superoxide dismutase (SOD) in the cytosolic and mitochondrial fraction. The changes in glutathione (GSH) paralleled those in GPx in the same experimental condition. Consistently, ginsenoside Re treatment exhibited significant protections against cytosolic and mitochondrial oxidative damage (i.e. lipid peroxidation and protein oxidation), mitochondrial translocation of PKCδ, mitochondrial dysfunction (mitochondrial transmembrane potential and intra-mitochondrial Ca2+), apoptotic events [i.e., cytochrome c release from mitochondria, cleavage of caspase-3 and poly(ADP-ribose)polymerase-1, nuclear condensation, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive apoptotic cells], and a reduction in the tyrosine hydroxylase (TH) expression and TH activity induced by MA in SH-SY5Y neuroblastoma cells. These protective effects of ginsenoside Re were comparable to those of PKCδ antisense oligonucleotide (ASO). However, ginsenoside Re did not significantly provide additional protective effects mediated by genetic inhibition of PKCδ. Our results suggest that PKCδ is a specific target for ginsenoside Re-mediated protective activity against MA toxicity in SH-SY5Y neuroblastoma cells. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Recently, we proposed that inhibition of protein kinase ( PK) C δ may be a useful target for protection against methamphetamine ( MA)-induced dopaminergic toxicity. We demonstrated that treatment with MA resulted in a significant decrease in phosphorylation of tyrosine hydroxylase ( TH) at Ser40 in the striatum, but not in the phosphorylation of TH at Ser31. In the present study, treatment with rottlerin (1.5 or 3.0 μg, i.c.v, once a day for 5 days), a PKC δ inhibitor, or a PKC δ antisense oligonucleotide ( ASO; 2.5 μg/μl, i.c.v., 3 times) significantly attenuated MA-induced reductions in the phosphorylation of TH at Ser40 and in the expression of PKA in the striatum of mice. This attenuation was significantly counteracted by H89 (10 or 30 ng, i.c.v., 1 h after the last MA administration), a PKA inhibitor. Treatment with rottlerin or ASO significantly attenuated the MA-induced increase in protein phosphatase ( PP) 2 A activity. FTY720 (1 or 5 mg/kg, i.p., 1 h after the last MA administration), a PP2 A activator, significantly reversed the recovery in TH phosphorylation mediated by inhibition of PKC δ after MA treatment. Both H89 and FTY720 counteracted the recovery of MA-induced behavioural impairments induced by PKC δ inhibition. The effects, mediated by rottlerin or ASO in MA-treated wild-type mice were comparable with those in MA-treated PKCδ −/− mice. However, neither inhibition of the mitogen-activated protein kinase subfamily (extracellular signal-regulated kinase, c- Jun N-terminal kinase, p38) nor inhibition of calcium calmodulin kinase II significantly altered PKC δ inhibition-mediated attenuation of MA-induced impairment of TH phosphorylation. The results suggest that genetic or pharmacological inhibition of PKC δ requires modulation of PKA expression and/or PP2 A activity to attenuate the impairment of TH phosphorylation at Ser40 and behavioural activity induced by MA. [ABSTRACT FROM AUTHOR]

We have demonstrated that mitochondrial oxidative damage and PKCδ overexpression contribute to methamphetamine-induced dopaminergic degeneration. Although it is recognized that antioxidant melatonin is effective in preventing neurotoxicity induced by methamphetamine, its precise mechanism remains elusive. C57BL/6J wild-type mice exhibited a similar degree of dopaminergic deficit when methamphetamine was administered during light and dark phases. Furthermore, dopaminergic neuroprotection by genetic inhibition of PKCδ during the light phase was comparable to that during the dark phase. Thus, we have focused on the light phase to examine whether melatonin modulates PKCδ-mediated neurotoxic signaling after multiple high doses of methamphetamine. To enhance the bioavailability of melatonin, we applied liposomal melatonin. Treatment with methamphetamine resulted in hyperthermia, mitochondrial translocation of PKCδ, oxidative damage (mitochondria > cytosol), mitochondrial dysfunction, pro-apoptotic changes, ultrastructural mitochondrial degeneration, dopaminergic degeneration, and behavioral impairment in wild-type mice. Treatment with liposomal melatonin resulted in a dose-dependent attenuation against degenerative changes induced by methamphetamine in wild-type mice. Attenuation by liposomal melatonin might be comparable to that by genetic inhibition (using PKCδ(−/−) mice or PKCδ antisense oligonucleotide). However, liposomal melatonin did not show any additional protective effects on the attenuation by genetic inhibition of PKCδ. Our results suggest that the circadian cycle cannot be a key factor in modulating methamphetamine toxicity under the current experimental condition and that PKCδ is one of the critical target genes for melatonin-mediated protective effects against mitochondrial burdens (dysfunction), oxidative stress, pro-apoptosis, and dopaminergic degeneration induced by methamphetamine. [ABSTRACT FROM AUTHOR]

We report a stimuli-responsive fluorescent nanomaterial, based on graphene oxide coupled with a polymer conjugated with photochromic spiropyran (SP) dye and hydrophobic boron dipyrromethane (BODIPY) dye, for application in triggered target multicolor bioimaging. Graphene oxide (GO) was reduced by catechol-conjugated polymers under mildly alkaline conditions, which enabled to formation of functionalized multicolor graphene nanoparticles that can be induced by irradiation with UV light and by changing the pH from acidic to neutral. Investigation of these nanoparticles by using AFM, fluorescence emission, and in vitro cell and in vivo imaging revealed that they show different tunable colors in bioimaging applications and, more specifically, in cancer-cell detection. The stability, biocompatibility, and quenching efficacy of this nanocomposite open a different perspective for cell imaging in different independent colors, sequentially and simultaneously. [ABSTRACT FROM AUTHOR]

We developed an analytical method using liquid–liquid extraction (LLE) and liquid chromatography–tandem mass spectrometry (LC‐MS/MS) to detect and quantify tebufenozide (TEB) and indoxacarb (IND) residues in animal and aquatic products (chicken muscle, milk, egg, eel, flatfish, and shrimp). The target compounds were extracted using 1% acetic acid (0.1% acetic acid for egg only) in acetonitrile and purified using n‐hexane. The analytes were separated on a Gemini‐NX C18 column using (a) distilled water with 0.1% formic acid and 5 mm ammonium acetate and (b) methanol with 0.1% formic acid as the mobile phase. All six‐point matrix‐matched calibration curves showed good linearity with coefficients of determination (R2) ≥0.9864 over a concentration range of 5–50 μg/kg. Intra‐ and inter‐day accuracy was expressed as the recovery rate at three spiking levels and ranged between 73.22 and 114.93% in all matrices, with a relative standard deviation (RSD, corresponding to precision) ≤13.87%. The limits of quantification (LOQ) of all target analytes ranged from 2 to 20 μg/kg, which were substantially lower than the maximum residue limits (MRLs) specified by the regulatory agencies of different countries. All samples were collected from different markets in Seoul, Republic of Korea, and tested negative for tebufenozide and indoxacarb residues. These results show that the method developed is robust and may be a promising tool to detect trace levels of the target analytes in animal products. [ABSTRACT FROM AUTHOR]

In article number 1703826, Jaeyun Kim and co‐workers report a new type of supertough hydrogel that exhibits enhanced mechanical stability under normal and physiological conditions. Various drugs loaded into the gel can be released on demand via mechanical stimulation, demonstrating the great potential of this approach for biological applications. [ABSTRACT FROM AUTHOR]

Recently, we proposed that inhibition of protein kinase (PK) Cδ may be a useful target for protection against methamphetamine (MA)-induced dopaminergic toxicity. We demonstrated that treatment with MA resulted in a significant decrease in phosphorylation of tyrosine hydroxylase (TH) at Ser(40) in the striatum, but not in the phosphorylation of TH at Ser(31) . In the present study, treatment with rottlerin (1.5 or 3.0 μg, i.c.v, once a day for 5 days), a PKCδ inhibitor, or a PKCδ antisense oligonucleotide (ASO; 2.5 μg/μl, i.c.v., 3 times) significantly attenuated MA-induced reductions in the phosphorylation of TH at Ser(40) and in the expression of PKA in the striatum of mice. This attenuation was significantly counteracted by H89 (10 or 30 ng, i.c.v., 1 h after the last MA administration), a PKA inhibitor. Treatment with rottlerin or ASO significantly attenuated the MA-induced increase in protein phosphatase (PP) 2A activity. FTY720 (1 or 5 mg/kg, i.p., 1 h after the last MA administration), a PP2A activator, significantly reversed the recovery in TH phosphorylation mediated by inhibition of PKCδ after MA treatment. Both H89 and FTY720 counteracted the recovery of MA-induced behavioural impairments induced by PKCδ inhibition. The effects, mediated by rottlerin or ASO in MA-treated wild-type mice were comparable with those in MA-treated PKCδ(-/-) mice. However, neither inhibition of the mitogen-activated protein kinase subfamily (extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38) nor inhibition of calcium calmodulin kinase II significantly altered PKCδ inhibition-mediated attenuation of MA-induced impairment of TH phosphorylation. The results suggest that genetic or pharmacological inhibition of PKCδ requires modulation of PKA expression and/or PP2A activity to attenuate the impairment of TH phosphorylation at Ser(40) and behavioural activity induced by MA., (© 2014 Wiley Publishing Asia Pty Ltd.)

A polyelectrolyte complex micelle (PECM)-based delivery system for targeting folate (FOL) receptor overexpressing tumor cells is demonstrated using poly(ethylene glycol) (PEG)-conjugated oligonucleotide (ODN). The tumor targeting property was conferred to the PECM by tethering a folate moiety to the distal end of the PEG segment in an anti-sense green fluorescent protein (GFP) ODN-PEG conjugate. Nanoscale PECMs were spontaneously produced from ionic interactions between the ODN-PEG-FOL conjugate and a cationic lipid, lipofectamine (Lf). When treated with FOL receptor overexpressing cells (KB), the PCEMs caused a significant reduction in GFP expression in a dose-dependent manner. This effect was not observed in FOL receptor deficient cells (A549). The enhanced transfection of ODN-PEG-FOL/Lf PECMs to KB cells was caused by FOL receptor mediated endocytosis. The efficiency of target-specific gene suppression by ODN-PEG-FOL/Lf PECMs was maintained even in the presence of 10% fetal bovine serum in the transfection medium.

Thermally sensitive poly(N-isopropylacrylamide, NIPAAm) hydrogel beads conjugated with a cell adhesive motif, GRGDY, were prepared and utilized as cell culture substrate for chondrocytes. They were produced to be uniform in size and distribution by using calcium alginate as a temporal mold. The RGD moieties were introduced, in a spatially selective manner, to the surface of the beads by conjugating GRGDY under the precollapsed state at a higher temperature above the lower critical solution temperature (LCST). These RGD-conjugated polyNIPAAm beads demonstrated a reversible swelling and deswelling behavior around the LCST, which enabled the chondrocytes attached on the surface of collapsed beads at 37 degrees C to readily detach when the temperature was shifted below 37 degrees C. The cell detachment percentage was largely affected by the temperature-dependent reswelling extent of the collapsed RGD-modified beads.