Comparison of Muscle Regeneration Effects at Different Melittin Concentrations in Rabbit Atrophied Muscle.

This research aimed to explore the healing impacts of Melittin treatment on gastrocnemius muscle wasting caused by immobilization with a cast in rabbits. Twenty-four rabbits were randomly allocated to four groups. The procedures included different injections: 0.2 mL of normal saline to Group 1 (G1-NS); 4 µg/kg of Melittin to Group 2 (G2-4 µg/kg Melittin); 20 µg/kg of Melittin to Group 3 (G3-20 µg/kg Melittin); and 100 µg/kg of Melittin to Group 4 (G4-100 µg/kg Melittin). Ultrasound was used to guide the injections into the rabbits' atrophied calf muscles following two weeks of immobilization via casting. Clinical measurements, including the length of the calf, the compound muscle action potential (CMAP) of the tibial nerve, and the gastrocnemius muscle thickness, were assessed. Additionally, cross-sectional slices of gastrocnemius muscle fibers were examined, and immunohistochemistry and Western blot analyses were performed following two weeks of therapy. The mean regenerative changes, as indicated by clinical parameters, in Group 4 were significantly more pronounced than in the other groups (p < 0.05). Furthermore, the cross-sectional area of the gastrocnemius muscle fibers and immunohistochemical indicators in Group 4 exceeded those in the remaining groups (p < 0.05). Western blot analysis also showed a more significant presence of anti-inflammatory and angiogenic cytokines in Group 4 compared to the others (p < 0.05). Melittin therapy at a higher dosage can more efficiently activate regeneration in atrophied gastrocnemius muscle compared to lower doses of Melittin or normal saline.

Transcriptional Changes in Radiation-Induced Lung Injury: A Comparative Analysis of Two Radiation Doses for Preclinical Research.

In a recent stereotactic body radiation therapy animal model, radiation pneumonitis and radiation pulmonary fibrosis were observed at around 2 and 6 weeks, respectively. However, the molecular signature of this model remains unclear. This study aimed to examine the molecular characteristics at these two stages using RNA-seq analysis. Transcriptomic profiling revealed distinct transcriptional patterns for each stage. Inflammatory response and immune cell activation were involved in both stages. Cell cycle processes and response to type II interferons were observed during the inflammation stage. Extracellular matrix organization and immunoglobulin production were noted during the fibrosis stage. To investigate the impact of a 10 Gy difference on fibrosis progression, doses of 45, 55, and 65 Gy were tested. A dose of 65 Gy was selected and compared with 75 Gy. The 65 Gy dose induced inflammation and fibrosis as well as the 75 Gy dose, but with reduced lung damage, fewer inflammatory cells, and decreased collagen deposition, particularly during the inflammation stage. Transcriptomic analysis revealed significant overlap, but differences were observed and clarified in Gene Ontology and KEGG pathway analysis, potentially influenced by changes in interferon-gamma-mediated lipid metabolism. This suggests the suitability of 65 Gy for future preclinical basic and pharmaceutical research connected with radiation-induced lung injury.

The miR-15b-Smurf2-HSP27 axis promotes pulmonary fibrosis.

BACKGROUND: Heat shock protein 27 (HSP27) is overexpressed during pulmonary fibrosis (PF) and exacerbates PF; however, the upregulation of HSP27 during PF and the therapeutic strategy of HSP27 inhibition is not well elucidated. METHODS: We have developed a mouse model simulating clinical stereotactic body radiotherapy (SBRT) with focal irradiation and validated the induction of RIPF. HSP25 (murine form of HSP27) transgenic (TG) and LLC1-derived orthotropic lung tumor models were also used. Lung tissues of patients with RIPF and idiopathic pulmonary fibrosis, and lung tissues from various fibrotic mouse models, as well as appropriated cell line systems were used. Public available gene expression datasets were used for therapeutic response rate analysis. A synthetic small molecule HSP27 inhibitor, J2 was also used. RESULTS: HSP27 expression with its phosphorylated form (pHSP27) increased during PF. Decreased mRNA expression of SMAD-specific E3 ubiquitin-protein ligase 2 (Smurf2), which is involved in ubiquitin degradation of HSP27, was responsible for the increased expression of pHSP27. In addition, increased expression of miRNA15b was identified with decreased expression of Smurf2 mRNA in PF models. Inverse correlation between pHSP27 and Smurf2 was observed in the lung tissues of PF animals, an irradiated orthotropic lung cancer models, and PF tissues from patients. Moreover, a HSP27 inhibitor cross-linked with HSP27 protein to ameliorate PF, which was more effective when targeting the epithelial to mesenchymal transition (EMT) stage of PF. CONCLUSIONS: Our findings identify upregulation mechanisms of HSP27 during PF and provide a therapeutic strategy for HSP27 inhibition for overcoming PF.

Early Prediction of Radiation-Induced Pulmonary Fibrosis Using Gastrin-Releasing Peptide Receptor-Targeted PET Imaging.

Early diagnosis of radiation-induced pulmonary fibrosis (RIPF) in lung cancer patients after radiation therapy is important. A gastrin-releasing peptide receptor (GRPR) mediates the inflammation and fibrosis after irradiation in mice lungs. Previously, our group synthesized a GRPR-targeted positron emission tomography (PET) imaging probe, [64Cu]Cu-NODAGA-galacto-bombesin (BBN), an analogue peptide of GRP. In this study, we evaluated the usefulness of [64Cu]Cu-NODAGA-galacto-BBN for the early prediction of RIPF. We prepared RIPF mice and acquired PET/CT images of [18F]F-FDG and [64Cu]Cu-NODAGA-galacto-BBN at 0, 2, 5, and 11 weeks after irradiation (n = 3-10). We confirmed that [64Cu]Cu-NODAGA-galacto-BBN targets GRPR in irradiated RAW 264.7 cells. In addition, we examined whether [64Cu]Cu-NODAGA-galacto-BBN monitors the therapeutic efficacy in RIPF mice (n = 4). As a result, the lung uptake ratio (irradiated-to-normal) of [64Cu]Cu-NODAGA-galacto-BBN was the highest at 2 weeks, followed by its decrease at 5 and 11 weeks after irradiation, which matched with the expression of GRPR and was more accurately predicted than [18F]F-FDG. These uptake results were also confirmed by the cell uptake assay. Furthermore, [64Cu]Cu-NODAGA-galacto-BBN could monitor the therapeutic efficacy of pirfenidone in RIPF mice. We conclude that [64Cu]Cu-NODAGA-galacto-BBN is a novel PET imaging probe for the early prediction of RIPF-targeting GRPR expressed during the inflammatory response.

Polydeoxyribonucleotide and Shock Wave Therapy Sequence Efficacy in Regenerating Immobilized Rabbit Calf Muscles.

This study primarily aimed to investigate the combined effects of polydeoxyribonucleotide (PDRN) and extracorporeal shock wave therapy (ESWT) sequences on the regenerative processes in atrophied animal muscles. Thirty male New Zealand rabbits, aged 12 weeks, were divided into five groups: normal saline (Group 1), PDRN (Group 2), ESWT (Group 3), PDRN injection before ESWT (Group 4), and PDRN injection after ESWT (Group 5). After 2 weeks of cast immobilization, the respective treatments were administered to the atrophied calf muscles. Radial ESWT was performed twice weekly. Calf circumference, tibial nerve compound muscle action potential (CMAP), and gastrocnemius (GCM) muscle thickness after 2 weeks of treatment were evaluated. Histological and immunohistochemical staining, as well as Western blot analysis, were conducted 2 weeks post-treatment. Staining intensity and extent were assessed using semi-quantitative scores. Groups 4 and 5 demonstrated significantly greater calf muscle circumference, GCM muscle thickness, tibial nerve CMAP, and GCM muscle fiber cross-sectional area (type I, type II, and total) than the remaining three groups (p < 0.05), while they did not differ significantly in these parameters. Groups 2 and 3 showed higher values for all the mentioned parameters than Group 1 (p < 0.05). Group 4 had the greatest ratio of vascular endothelial growth factor (VEGF) to platelet endothelial cell adhesion molecule-1 (PECAM-1) in the GCM muscle fibers compared to the other four groups (p < 0.05). Western blot analysis revealed significantly higher expression of angiogenesis cytokines in Groups 4 and 5 than in the other groups (p < 0.05). The combination of ESWT and PDRN injection demonstrated superior regenerative efficacy for atrophied calf muscle tissue in rabbit models compared to these techniques alone or saline. In particular, administering ESWT after PDRN injection yielded the most favorable outcomes in specific parameters.

NXC736 Attenuates Radiation-Induced Lung Fibrosis via Regulating NLRP3/IL-1ß Signaling Pathway.

Radiation-induced lung fibrosis (RILF) is a common complication of radiotherapy in lung cancer. However, to date no effective treatment has been developed for this condition. NXC736 is a novel small-molecule compound that inhibits NLRP3, but its effect on RILF is unknown. NLRP3 activation is an important trigger for the development of RILF. Thus, we aimed to evaluate the therapeutic effect of NXC736 on lung fibrosis inhibition using a RILF animal model and to elucidate its molecular signaling pathway. The left lungs of mice were irradiated with a single dose of 75 Gy. We observed that NXC736 treatment inhibited collagen deposition and inflammatory cell infiltration in irradiated mouse lung tissues. The damaged lung volume, evaluated by magnetic resonance imaging, was lower in NXC736-treated mice than in irradiated mice. NXC736-treated mice exhibited significant changes in lung function parameters. NXC736 inhibited inflammasome activation by interfering with the NLRP3-ASC-cleaved caspase-1 interaction, thereby reducing the expression of IL-1ß and blocking the fibrotic pathway. In addition, NXC736 treatment reduced the expression of epithelial-mesenchymal transition markers such as α-SMA, vimentin, and twist by blocking the Smad 2,3,4 signaling pathway. These data suggested that NXC736 is a potent therapeutic agent against RILF.

Efferocytosis and enhanced FPR2 expression following apoptotic cell instillation attenuate radiation-induced lung inflammation and fibrosis.

Lung inflammation and fibrosis are common side effects of radiotherapy that can lead to serious reduction in the quality of life of patients. However, no effective treatment is available, and the mechanisms underlying its pathophysiology are poorly understood. Irradiation increases formyl peptide receptor 2 (FPR2) expression in lung tissue, and FPR2 agonists are known to promote the uptake of apoptosis cells, referred to as efferocytosis that is a hallmark of the resolution of inflammation. Herein, in a mouse model of radiation-induced lung injury (RILI), efferocytosis was induced by injecting apoptotic cells into the lung through the trachea, and its correlation with FPR expression and the effect of efferocytosis and FPR expression on RILI were assessed. Interestingly, when apoptotic cells were injected into the lung, the radiation-induced increase in FPR2 expression was further amplified. In the mouse model of RILI, apoptotic cell instillation reduced the volume of the damaged lung and prevented the decrease in lung function. Additionally, the expression of inflammatory cytokines, fibrosis-related markers, and oxidative stress-related markers was reduced by apoptotic cell instillation. Co-administration of apoptotic Jurkat cells and WRW4, the FPR2 antagonist, reversed these effects. These findings suggest that efferocytosis induced by apoptotic cell instillation and enhanced FPR2 expression attenuate RILI, thereby alleviating lung inflammation and fibrosis.

A PGC1α-mediated transcriptional axis suppresses melanoma metastasis.

Melanoma is the deadliest form of commonly encountered skin cancer because of its rapid progression towards metastasis. Although metabolic reprogramming is tightly associated with tumour progression, the effect of metabolic regulatory circuits on metastatic processes is poorly understood. PGC1α is a transcriptional coactivator that promotes mitochondrial biogenesis, protects against oxidative stress and reprograms melanoma metabolism to influence drug sensitivity and survival. Here, we provide data indicating that PGC1α suppresses melanoma metastasis, acting through a pathway distinct from that of its bioenergetic functions. Elevated PGC1α expression inversely correlates with vertical growth in human melanoma specimens. PGC1α silencing makes poorly metastatic melanoma cells highly invasive and, conversely, PGC1α reconstitution suppresses metastasis. Within populations of melanoma cells, there is a marked heterogeneity in PGC1α levels, which predicts their inherent high or low metastatic capacity. Mechanistically, PGC1α directly increases transcription of ID2, which in turn binds to and inactivates the transcription factor TCF4. Inactive TCF4 causes downregulation of metastasis-related genes, including integrins that are known to influence invasion and metastasis. Inhibition of BRAFV600E using vemurafenib, independently of its cytostatic effects, suppresses metastasis by acting on the PGC1α-ID2-TCF4-integrin axis. Together, our findings reveal that PGC1α maintains mitochondrial energetic metabolism and suppresses metastasis through direct regulation of parallel acting transcriptional programs. Consequently, components of these circuits define new therapeutic opportunities that may help to curb melanoma metastasis.

2-Methoxyestradiol Inhibits Radiation-Induced Skin Injuries.

Radiation-induced skin injury (RISI) is a main side effect of radiotherapy for cancer patients, with vascular damage being a common pathogenesis of acute and chronic RISI. Despite the severity of RISI, there are few treatments for it that are in clinical use. 2-Methoxyestradiol (2-ME) has been reported to regulate the radiation-induced vascular endothelial-to-mesenchymal transition. Thus, we investigated 2-ME as a potent anti-cancer and hypoxia-inducible factor 1 alpha (HIF-1α) inhibitor drug that prevents RISI by targeting HIF-1α. 2-ME treatment prior to and post irradiation inhibited RISI on the skin of C57/BL6 mice. 2-ME also reduced radiation-induced inflammation, skin thickness, and vascular fibrosis. In particular, post-treatment with 2-ME after irradiation repaired the damaged vessels on the irradiated dermal skin, inhibiting endothelial HIF-1α expression. In addition to the increase in vascular density, post-treatment with 2-ME showed fibrotic changes in residual vessels with SMA+CD31+ on the irradiated skin. Furthermore, 2-ME significantly inhibited fibrotic changes and accumulated DNA damage in irradiated human dermal microvascular endothelial cells. Therefore, we suggest that 2-ME may be a potent therapeutic agent for RISI.

Arctigenin induces necroptosis through mitochondrial dysfunction with CCN1 upregulation in prostate cancer cells under lactic acidosis.

Arctigenin, a mitochondrial complex I inhibitor, has been identified as a potential anti-tumor agent, but the involved mechanism still remains elusive. Herein, we studied the underlying mechanism(s) of action of arctigenin on acidity-tolerant prostate cancer PC-3AcT cells in the lactic acid-containing medium. At concentration showing no toxicity on normal prostate epithelial RWPE-1 and HPrEC cells, arctigenin alone or in combination with docetaxel induced significant cytotoxicity in PC-3AcT cells compared to parental PC-3 cells. With arctigenin treatment, reactive oxygen species (ROS) levels, annexin V-PE positive fractions, sub-G0/G1 peak in cell cycle analysis, mitochondrial membrane depolarization, and cell communication network factor 1 (CCN1) levels were increased, while cellular ATP content and phospho (p)-Akt level were decreased. Pretreatment with ROS scavenger N-acetylcysteine effectively reversed the series of phenomena caused by arctigenin, suggesting that ROS served as upstream molecules of arctigenin-driven cytotoxicity. Meanwhile, arctigenin increased the levels of p-receptor-interacting serine/threonine-protein kinase 3 (p-RIP3) and p-mixed lineage kinase domain-like pseudokinase (p-MLKL) as necroptosis mediators, and pretreatment with necroptosis inhibitor necrostatin-1 restored their levels and cell viability. Treatment of spheroids with arctigenin resulted in necroptotic cell death, which was prevented by N-acetylcysteine. The siRNA-based knockdown of CCN1 suppressed the levels of MLKL, B-cell lymphoma 2 (Bcl-2), and induced myeloid leukemia cell differentiation (Mcl-1) with increased cleavage of Bcl-2-associated X (Bax) and caspase-3. Collectively, these results provide new insights into the molecular mechanisms underlying arctigenin-induced cytotoxicity, and support arctigenin as a potential therapeutic agent for targeting non-Warburg phenotype through induction of necroptosis via ROS-mediated mitochondrial damage and CCN1 upregulation.

Cyclin D1-Cdk4 controls glucose metabolism independently of cell cycle progression.

Insulin constitutes a principal evolutionarily conserved hormonal axis for maintaining glucose homeostasis; dysregulation of this axis causes diabetes. PGC-1α (peroxisome-proliferator-activated receptor-γ coactivator-1α) links insulin signalling to the expression of glucose and lipid metabolic genes. The histone acetyltransferase GCN5 (general control non-repressed protein 5) acetylates PGC-1α and suppresses its transcriptional activity, whereas sirtuin 1 deacetylates and activates PGC-1α. Although insulin is a mitogenic signal in proliferative cells, whether components of the cell cycle machinery contribute to its metabolic action is poorly understood. Here we report that in mice insulin activates cyclin D1-cyclin-dependent kinase 4 (Cdk4), which, in turn, increases GCN5 acetyltransferase activity and suppresses hepatic glucose production independently of cell cycle progression. Through a cell-based high-throughput chemical screen, we identify a Cdk4 inhibitor that potently decreases PGC-1α acetylation. Insulin/GSK-3ß (glycogen synthase kinase 3-beta) signalling induces cyclin D1 protein stability by sequestering cyclin D1 in the nucleus. In parallel, dietary amino acids increase hepatic cyclin D1 messenger RNA transcripts. Activated cyclin D1-Cdk4 kinase phosphorylates and activates GCN5, which then acetylates and inhibits PGC-1α activity on gluconeogenic genes. Loss of hepatic cyclin D1 results in increased gluconeogenesis and hyperglycaemia. In diabetic models, cyclin D1-Cdk4 is chronically elevated and refractory to fasting/feeding transitions; nevertheless further activation of this kinase normalizes glycaemia. Our findings show that insulin uses components of the cell cycle machinery in post-mitotic cells to control glucose homeostasis independently of cell division.

The deacetylase Sirt6 activates the acetyltransferase GCN5 and suppresses hepatic gluconeogenesis.

Hepatic glucose production (HGP) maintains blood glucose levels during fasting but can also exacerbate diabetic hyperglycemia. HGP is dynamically controlled by a signaling/transcriptional network that regulates the expression/activity of gluconeogenic enzymes. A key mediator of gluconeogenic gene transcription is PGC-1α. PGC-1α's activation of gluconeogenic gene expression is dependent upon its acetylation state, which is controlled by the acetyltransferase GCN5 and the deacetylase Sirt1. Nevertheless, whether other chromatin modifiers-particularly other sirtuins-can modulate PGC-1α acetylation is currently unknown. Herein, we report that Sirt6 strongly controls PGC-1α acetylation. Surprisingly, Sirt6 induces PGC-1α acetylation and suppresses HGP. Sirt6 depletion decreases PGC-1α acetylation and promotes HGP. These acetylation effects are GCN5 dependent: Sirt6 interacts with and modifies GCN5, enhancing GCN5's activity. Lepr(db/db) mice, an obese/diabetic animal model, exhibit reduced Sirt6 levels; ectopic re-expression suppresses gluconeogenic genes and normalizes glycemia. Activation of hepatic Sirt6 may therefore be therapeutically useful for treating insulin-resistant diabetes.

Apigenin causes necroptosis by inducing ROS accumulation, mitochondrial dysfunction, and ATP depletion in malignant mesothelioma cells.

Apigenin, a naturally occurring flavonoid, is known to exhibit significant anticancer activity. This study was designed to determine the effects of apigenin on two malignant mesothelioma cell lines, MSTO-211H and H2452, and to explore the underlying mechanism(s). Apigenin significantly inhibited cell viability with a concomitant increase in intracellular reactive oxygen species (ROS) and caused the loss of mitochondrial membrane potential (Δ𝚿m), and ATP depletion, resulting in apoptosis and necroptosis in monolayer cell culture. Apigenin upregulated DNA damage response proteins, including the DNA double strand break marker phospho (p)- histone H2A.X. and caused a transition delay at the G2/M phase of cell cycle. Western blot analysis showed that apigenin treatment upregulated protein levels of cleaved caspase-3, cleaved PARP, p-MLKL, and p-RIP3 along with an increased Bax/Bcl-2 ratio. ATP supplementation restored cell viability and levels of DNA damage-, apoptosisand necroptosis-related proteins that apigenin caused. In addition, N-acetylcysteine reduced ROS production and improved Δ𝚿m loss and cell death that were caused by apigenin. In a 3D spheroid culture model, ROS-dependent necroptosis was found to be a mechanism involved in the anti-cancer activity of apigenin against malignant mesothelioma cells. Taken together, our findings suggest that apigenin can induce ROS-dependent necroptotic cell death due to ATP depletion through mitochondrial dysfunction. This study provides us a possible mechanism underlying why apigenin could be used as a therapeutic candidate for treating malignant mesothelioma.

Mussel adhesive Protein-conjugated Vitronectin (fp-151-VT) Induces Anti-inflammatory Activity on LPS-stimulated Macrophages and UVB-irradiated Keratinocytes.

BACKGROUND: Skin inflammation and dermal injuries are a major clinical problem because current therapies are limited to treating established scars, and there is a poor understanding of healing mechanisms. Mussel adhesive proteins (MAPs) have great potential in many tissue engineering and biomedical applications. It has been successfully demonstrated that the redesigned hybrid type MAP (fp-151) can be utilized as a promising adhesive biomaterial. The aim of this study was to develop a novel recombinant protein using fp-151 and vitronectin (VT) and to elucidate the anti-inflammatory effects of this recombinant protein on macrophages and keratinocytes. METHODS: Lipopolysaccharide (LPS) was used to stimulate macrophages and UVB was used to stimulate keratinocytes. Inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 were analyzed by Western Blot. Inflammatory cytokines and NO and ROS production were analyzed. RESULT: In macrophages stimulated by LPS, expression of the inflammatory factors iNOS, COX-2, and NO production increased, while the r-fp-151-VT-treated groups had suppressed expression of iNOS, COX-2, and NO production in a dose-dependent manner. In addition, keratinocytes stimulated by UVB and treated with r-fp-151-VT had reduced expression of iNOS and COX-2. Interestingly, in UVB-irradiated keratinocytes, inflammatory cytokines, such as interleukin (IL)-1b, IL-6, and tumor necrosis factor (TNF)-a, were significantly reduced by r-fp-151-VT treatment. CONCLUSIONS: These results suggest that the anti-inflammatory activity of r-fp-151-VT was more effective in keratinocytes, suggesting that it can be used as a therapeutic agent to treat skin inflammation.

Short-term cone-beam computed tomography evaluation of maxillary third molar changes after total arch distalization in adolescents.

INTRODUCTION: Our objectives were to evaluate changes in the position of maxillary third molars with cone-beam computed tomography images in adolescents after total arch distalization using a modified C-palatal plate (MCPP) and to compare them with the changes in a matched control group. METHODS: We included 68 maxillary third molars of 40 adolescent patients (mean age, 12.6 years). They were divided into MCPP and control groups. Cone-beam computed tomography images were taken before and after molar distalization (mean duration, 14.4 months) in the MCPP group and also in the control group (mean duration, 12.9 months). The changes in the position, angulation, and rotation of the third molars were assessed, and the volumes of maxillary tuberosity were measured. RESULTS: After distalization, the third molars moved backward (1.2 mm) and upward (0.5 mm) in the MCPP group with a significant difference (P <0.003), and they moved downward and forward in the control group. The changes in rotation and angulation were insignificant. The volumes of maxillary tuberosity increased in both groups. CONCLUSIONS: Maxillary total arch distalization caused unerupted third molars to move backward and upward, with an insignificant difference in the posttreatment volume of maxillary tuberosity. Therefore, it may be possible to perform maxillary total arch distalization in adolescents with unerupted third molars without a germectomy, at least in the short term.

Arctigenin shows preferential cytotoxicity to acidity-tolerant prostate carcinoma PC-3 cells through ROS-mediated mitochondrial damage and the inhibition of PI3K/Akt/mTOR pathway.

Extracellular acidity in the tumor microenvironment contributes to chemoresistance of malignant tumors. The objective of this study was to determine anticancer effects of arctigenin, a novel anti-inflammatory lignan extracted from seeds of Arctium lappa, on acidity-tolerant prostate cancer PC-3AcT cells. The PC-3AcT cells manifested increased tolerance to low-pH media with enhanced percent cell viability and increased resistance to docetaxel compared to their parental PC-3 cells. Arctigenin alone or in combination with docetaxel induced potent cytotoxicity. Preferential sensitization of PC-3AcT cells to arctigenin was accompanied by increased cell fractions with sub-G0/G1 peak and annexin V-PE(+), increased ROS levels, decreased mitochondrial membrane potential and cellular ATP content, and inhibition of PI3K/Akt/mTOR pathway. A series of changes caused by arctigenin were efficiently reversed through reducing ROS levels by radical scavenger N-acetylcysteine, thus placing ROS upstream of arctigenin-driven cytotoxicity. Collectively, these results demonstrate that arctigenin can increase oxidative stress-mediated mitochondrial damage of acidity-tolerant PC-3AcT cells, suggesting that arctigenin might be a potential therapeutic candidate to overcome acidic-microenvironment-associated chemotherapeutic resistance in prostate cancer.

Therapeutic effect of microcurrent on calf muscle atrophy in immobilized rabbit.

INTRODUCTION: Immobilization causes significant muscle loss. In this study we assessed the regenerative effect of microcurrent electrical stimulation (MES) on gastrocnemius muscle (GCM) atrophy induced by immobilization by cast (IC) in rabbits. METHODS: Fifteen rabbits were divided into 3 groups: IC (group 1); IC and free re-ambulation for 2 weeks after cast removal (CR) (group 2); and IC and MES for 2 weeks after CR (group 3). We evaluated clinical parameters (calf circumference, compound muscle action potential of tibial nerve, and thickness of GCM by ultrasound), histomorphometric data (muscle composition and cross-sectional area), and immunohistochemistry. RESULTS: Mean atrophic changes in clinical parameters in group 3 were significantly less than those in groups 1 and 2 (P < 0.05). Histomophometric and immunohistochemical parameters in group 3 were significantly greater than those in groups 1 and 2, respectively (P < 0.05). DISCUSSION: MES prevents muscle atrophy and facilitates regeneration of muscle. Muscle Nerve 58: 270-276, 2018.

Probiotic fermentation augments the skin anti-photoaging properties of Agastache rugosa through up-regulating antioxidant components in UV-B-irradiated HaCaT keratinocytes.

BACKGROUND: Agastache rugosa (Fisch. & C.A.Mey.) Kuntze (Korean mint) is used to treat diverse types of human disorders in traditional medicine. In recent years, its non-fermented leaf extract (ARE) has been shown to possess protective properties against ultraviolet-B (UV-B) radiation-induced photooxidative stress. The present work aimed to examine whether probiotic bacterial fermentation would potentiate the skin anti-photoaging activity of ARE or not, by comparing the protective properties of ARE and corresponding fermented extract (ARE-F) against UV-B radiation-induced photooxidative stress in HaCaT keratinocytes. METHODS: ARE-F was produced from ARE by the fermentation with Lactobacillus rhamnosus HK-9, a type of Gram-positive probiotic bacterial strain. Anti-photoaging activities were evaluated by analyzing reactive oxygen species (ROS), promatrix metalloproteinases (proMMPs), total glutathione (GSH) and total superoxide dismutase (SOD) in UV-B-irradiated HaCaT keratinocytes. Antiradical activity was determined using 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay. RESULTS: ARE-F contained higher attenuating activity on the UV-B-induced ROS generation than ARE. Similarly, ARE-F was able to diminish the UV-B-induced proMMP-9 and -2 more effectively than ARE. ARE-F displayed higher tendencies to augment the UV-B-reduced total GSH content and SOD activity than ARE. However, there were no significant difference between ARE and ARE-F in ABTS radical scavenging activities. CONCLUSIONS: The findings suggest that the UV-B radiation-protective activity of ARE is enhanced by probiotic bacterial fermentation, which might improve the therapeutic and cosmetic values of A. rugosa leaves.

Protective properties of geniposide against UV-B-induced photooxidative stress in human dermal fibroblasts.

CONTEXT: Geniposide (genipin-1-O-ß-d-glucoside) is a major bioactive ingredient in the fruits of gardenia [Gardenia jasminoides J. Ellis (Rubiaceae)], a traditional herbal medicine in Asian countries. OBJECTIVE: This work assesses the skin anti-photoaging potential of geniposide in human dermal fibroblasts under UV-B irradiation. MATERIALS AND METHODS: The anti-photoaging property of geniposide, at varying concentrations (5, 12 and 30 µM) treated for 30 min prior to UV-B irradiation, was evaluated by analysing reactive oxygen species (ROS), promatrix metalloproteinase-2 (proMMP-2), glutathione (GSH), superoxide dismutase (SOD), nuclear factor erythroid 2-related factor 2 (Nrf2) and cellular viability. RESULTS: Geniposide suppressed the ROS elevation under UV-B irradiation, which was revealed using three ROS-sensitive fluorescent dyes. The use of 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA), dihydroethidium (DHE) and dihydrorhodamine 123 (DHR-123) elicited the IC50 values of 10.5, 9.8 and 21.0 µM, respectively. Geniposide attenuated proMMP-2 at activity and protein levels that were elevated under UV-B-irradiation. Geniposide at 5, 12 and 30 µM augmented the UV-B-reduced total GSH content to 1.9 ± 0.1-, 2.2 ± 0.2- and 4.1 ± 0.2-fold, respectively. Geniposide at 5, 12 and 30 µM upregulated total SOD activity to 2.3 ± 0.1-, 2.5 ± 0.3- and 3.3 ± 0.3-fold, respectively, under UV-B irradiation. The UV-B-reduced Nrf2 levels were also upregulated by geniposide treatment. Geniposide, at the concentrations used, was unable to interfere with cellular viabilities under UV-B irradiation. DISCUSSION AND CONCLUSIONS: After the skin anti-photoaging potential of geniposide may be further verified, it can be utilized as a safer resource in the manufacture of effective anti-aging cosmetics.

Pro-apoptotic Noxa is involved in ablative focal irradiation-induced lung injury.

Although lung injury including fibrosis is a well-documented side effect of lung irradiation, the mechanisms underlying its pathology are poorly understood. X-rays are known to cause apoptosis in the alveolar epithelial cells of irradiated lungs, which results in fibrosis due to the proliferation and differentiation of fibroblasts and the deposition of collagen. Apoptosis and BH3-only pro-apoptotic proteins have been implicated in the pathogenesis of pulmonary fibrosis. Recently, we have established a clinically analogous experimental model that reflects focal high-dose irradiation of the ipsilateral lung. The goal of this study was to elucidate the mechanism underlying radiation-induced lung injury based on this model. A radiation dose of 90 Gy was focally delivered to the left lung of C57BL/6 mice for 14 days. About 9 days after irradiation, the mice began to show increased levels of the pro-apoptotic protein Noxa in the irradiated lung alongside increased apoptosis and fibrosis. Suppression of Noxa expression by small interfering RNA protected cells from radiation-induced cell death and decreased expression of fibrogenic markers. Furthermore, we showed that reactive oxygen species participate in Noxa-mediated, radiation-induced cell death. Taken together, our results show that Noxa is involved in X-ray-induced lung injury.