Phyllodulcin from the hexane fraction of Hydrangea macrophylla inhibits glucose-induced lipid accumulation and reactive oxygen species generation in Caenorhabditis elegans.

We confirmed that the hexane layer of Hydrangea macrophylla leaf extract (HLH) is rich in phyllodulcin (PD), an alternative sweetener, through high performance liquid chromatography (HPLC) analysis. To investigate in vivo activity of HLH and its PD, acute toxicity and growth rate of Caenorhabditis elegans were tested and there are no clinical abnormalities at 125-500 µg/mL of HLH. HLH decreased the total lipid and triglyceride contents dose-dependently in glucose-induced obese worms. Also, HLH increased survival rates under oxidative and thermal stress and decreased body reactive oxygen species (ROS) contents significantly. Such antioxidant properties of HLH were attributed to the enhanced activity of the antioxidant enzyme catalase. To determine whether the effect of HLH was due to PD, worms were treated with PD (concentration contained in HLH), and inhibitory effects on total lipids and ROS were observed. Our results suggest that HLH and its PD as a natural alternative sweetener can be used as materials to improve metabolic diseases.

Autumn Olive (Elaeagnus umbellata Thunb.) Berries Improve Lipid Metabolism and Delay Aging in Middle-Aged Caenorhabditis elegans.

This study evaluated the positive effects of autumn olive berries (AOBs) extract on delaying aging by improving lipid metabolism in middle-aged Caenorhabditis elegans that had become obese due to a high-glucose (GLU) diet. The total phenolic content and DPPH radical scavenging abilities of freeze-dried AOBs (FAOBs) or spray-dried AOBs (SAOBs) were examined, and FAOBs exhibited better antioxidant activity. HPLC analysis confirmed that catechin is the main phenolic compound of AOBs; its content was 5.95 times higher in FAOBs than in SAOBs. Therefore, FAOBs were used in subsequent in vivo experiments. FAOBs inhibited lipid accumulation in both the young adult and middle-aged groups in a concentration-dependent manner under both normal and 2% GLU conditions. Additionally, FAOBs inhibited ROS accumulation in a concentration-dependent manner under normal and 2% GLU conditions in the middle-aged worms. In particular, FAOB also increased body bending and egg production in middle-aged worms. To confirm the intervention of genetic factors related to lipid metabolism from the effects of FAOB, body lipid accumulation was confirmed using worms deficient in the daf-16, atgl-1, aak-1, and akt-1 genes. Regarding the effect of FAOB on reducing lipid accumulation, the impact was nullified in daf-16-deficient worms under the 2% GLU condition, and nullified in both the daf-16- and atgl-1-deficient worms under fasting conditions. In conclusion, FAOB mediated daf-16 and atgl-1 to regulate lipogenesis and lipolysis in middle-aged worms. Our findings suggest that FAOB improves lipid metabolism in metabolically impaired middle-aged worms, contributing to its age-delaying effect.

Chlorogenic Acid of Cirsium japonicum Resists Oxidative Stress Caused by Aging and Prolongs Healthspan via SKN-1/Nrf2 and DAF-16/FOXO in Caenorhabditis elegans.

To evaluate the value of Cirsium japonicum (CJ; thistle) as a material for functional foods, we studied the functional composition of cultivated CJ and the in vitro and in vivo antioxidant activity of the functional substance. The detected phenolics in farmed CJ were chlorogenic acid (CA), linarin (LIN), and pectolinarin (PLIN) by HPLC analysis. As a result of the antioxidant activity of CJ and its phenolics by DPPH and ABTS method, CA had shown the greatest antioxidant activity. We employed Caenorhabditis elegans to validate that in vitro effects of CA are shown in vivo. CA delayed reduction in pumping rate and progeny production during aging of C. elegans. Under both normal and oxidative stress conditions, CA reduced the production of reactive oxygen species (ROS) in worms and increased their lifespan. In particular, CA showed the reducing effect of ROS accumulation due to aging in aged worms (8 days old). To gain insight into the mechanism, we used skn-1/Nrf2 and daf-16/FOXO transformed worms. The CA effects (on catalase activity and lifespan extension) in the wild-type (WT) decreased in skn-1 and daf-16 mutants. In particular, CA strongly relied on daf-16 under mild oxidative condition and skn-1 under overall (from mild to strong) oxidative stress to reduce ROS and extend healthspan. Thus, we conclude that CA, a key bioactive phenolic of CJ, reduces ROS production and ultimately extends healthspan, and this effect is the result of actions of daf-16 or skn-1 at different stages depending on the degree of oxidation or aging. Our results suggest that CJ containing CA can be used as an antiaging material due to its antioxidant properties.

Indian Almond (Terminalia catappa Linn.) Leaf Extract Extends Lifespan by Improving Lipid Metabolism and Antioxidant Activity Dependent on AMPK Signaling Pathway in Caenorhabditis elegans under High-Glucose-Diet Conditions.

This study aimed to evaluate the antioxidant and antiaging effects of Indian almond (Terminalia catappa Linn.) leaf extract (TCE) on high-glucose (GLU)-induced obese Caenorhabditis elegans. Since TCE contains high contents of flavonoids and phenolics, strong radical scavenging activity was confirmed in vitro. The stress-resistance effect of TCE was confirmed under thermal and oxidative stress conditions at nontoxic tested concentrations (6.25, 12.5, and 25 µg/mL). GLU at 2% caused lipid and reactive oxygen species (ROS) accumulation in C. elegans, and TCE inhibited lipid and ROS accumulation under both normal and 2% GLU conditions in a concentration-dependent manner. In addition, TCE proved to be effective in prolonging the lifespan of C. elegans under normal and 2% GLU conditions. The ROS reduction effect of TCE was abolished in mutants deficient in daf-16/FOXO and skn-1/Nrf-2. In addition, the lifespan-extending effect of TCE in these two mutants disappeared. The lifespan-extending effect was abolished even in atgl-1/ATGL-deficiency mutants. The TCE effect was reduced in aak-1/AMPK-deficient mutants and completely abolished under 2% GLU conditions. Therefore, the effect of prolonging lifespan by inhibiting lipid and ROS accumulation under the high GLU conditions of TCE is considered to be the result of atgl-1, daf-16, and skn-1 being downregulated by aak-1. These results suggest that the physiological potential of TCE contributes to antiaging under metabolic disorders.

Schisandrin C isolated from Schisandra chinensis fruits inhibits lipid accumulation by regulating adipogenesis and lipolysis through AMPK signaling in 3T3-L1 adipocytes.

In this study, lignans of Schisandra chinensis fruits (SCF) were profiled using HPLC-MS/MS, and the inhibitory effects of nine of these lignans were evaluated on triglyceride (TG) accumulation. We then examined the effects and molecular mechanisms on adipogenesis and lipolysis of schisandrin C (SC), which most inhibited TG levels during adipogenesis of 3T3-L1 cells. Treatment of 3T3-L1 cells with SC markedly decreased adipocyte differentiation but did not influence cell proliferation. During adipogenesis, SC significantly reduced total lipid and TG contents and down-regulated the mRNA expressions of C/EBPα, PPARγ, SREBP1c, aP2, and FAS. In addition, SC significantly increased p-AMPK, and this activation regulated the protein levels of major adipogenic transcription factors (PPARγ and C/EBPα). Furthermore, SC lowered the mRNA expressions of HSL and perilipin and inhibited pancreatic lipase levels, which are both related to lipolysis. PRACTICAL APPLICATIONS: Our results indicate that SC regulates lipogenesis and lipolysis by increasing AMPK phosphorylation and suggest that it may be beneficial for preventing obesity and related metabolic diseases. Thus, this study proposes a mechanical basis for developing SC-containing foods as a beneficial dietary strategy.

Anti-obesity effects of agar (Gelidium amansii)-derived oligosaccharides in high-fat diet-treated C57BL/6N mice due to differential regulations of lipogenesis and lipolysis.

To investigate the effects of agar oligosaccharides (AO) on lipid metabolism, changes in obesity phenotypes and related molecular factors were evaluated in C57BL/6N mice fed a high-fat diet (HFD). When HFD-induced obese mice were fed AO, they lost weight. Also, fat accumulation in abdominal and liver tissues was lower in the AO groups than in the Vehicle group. Lipid droplet sizes in tissue sections were reduced by AO, and these observations were mirrored by serum lipid contents. To evaluate the effects of AO on lipid metabolism, lipogenesis and lipolysis-related factors were analyzed. The mRNA expressions of genes involved in lipogenesis, such as adipocyte-protein 2 (aP2) and fatty acid synthase (FAS), were reduced by AO administration, and the expressions of lipolysis-associated proteins, including perilipin, hormone-sensitive lipase (HSL), and fat triglyceride lipase (ATGL), were increased. Taken together, our results suggest that AO should be considered a valuable natural agent that inhibits obesity.

Combined Treatment of Monopolar and Bipolar Radiofrequency Increases Skin Elasticity by Decreasing the Accumulation of Advanced Glycated End Products in Aged Animal Skin.

It is well known that skin aging is related to the destruction of collagen and elastin fibers by metalloproteinases (MMPs). Aged fibroblasts have a decreased ability to synthesize collagen and elastin. Nuclear factor erythroid 2-related factor 2 (NRF2) involves glyoxalase (GLO) activation, which inhibits the production of advanced glycated end products (AGE) and the expression of its receptor (RAGE). RAGE increases nuclear transcription factor-kappa B (NF-κB), which upregulates MMPs and decreases skin elasticity. NRF2 also decreases M1 macrophages, which secrete tumor necrosis factor-alpha (TNF-α), thereby decreasing AGE production. It is well known that radiofrequency (RF) decreases skin elasticity by increasing collagen synthesis. We evaluated whether RF increases skin elasticity via NRF2/GLO and whether they decrease AGE and RAGE expression in aged animal skin. We also compared the effects of RF based on the modes (monopolar or bipolar) or the combination used. In aged skin, NRF2, GLO-1, and M2 macrophage expression was decreased, and their expression increased when RF was applied. M1 and TNF-α demonstrated increased expression in the aged skin and decreased expression after RF application. AGE accumulation and RAGE, NF-κB, and MMP2/3/9 expression were increased in the aged skin, and they were decreased by RF. The papillary and reticular fibroblast markers showed decreased expression in young skin and increased expression in aged skin. The densities of collagen and elastin fiber in the aged skin were low, and they were increased by RF. In conclusion, RF leads to increased collagen and elastin fibers by increasing NRF2/GLO-1 and modulating M1/M2 polarization, which leads to decreased AGE and RAGE and, consequently, decreased NF-κB, which eventually slows collagen and elastin destruction. RF also leads to increased collagen and elastin fiber synthesis by increasing papillary and reticular fibroblast expression.

The Effect of Juingong Meditation on the Theta to Alpha Ratio in the Temporoparietal and Anterior Frontal EEG Recordings.

(1) Background: The effect of Juingong meditation on brainwave patterns has not been explored yet. This study aimed to study the changes in brainwave patterns produced by Juingong meditation, through electroencephalography (EEG) measurements. (2) Methods: The study included 23 participants from the Hanmaum Seon Center in Korea. EEG measurements were performed using InteraXon's four-channel EEG measurement equipment, Muse. It measures EEG patterns in the temporoparietal and anterior frontal lobes. Brainwaves were measured in two different states: when Juingong meditation was practiced and when instructed mind wandering (IMW) was practiced. The EEG recordings were analyzed using the theta/alpha index. (3) Results: In the Juingong meditation state, the power of alpha was relatively higher than that of theta and these results were valid in the temporal parietal lobe channel. This indicates that relatively more alpha waves were induced in the temporal parietal lobe when Juingong meditation was practiced. (4) Conclusions: When Juingong meditation is practiced, the theta/alpha ratio changes without delay, which means that the practical effect of Juingong meditation on brainwave patterns is immediately apparent.

Loperamide-induced Constipation Activates Inflammatory Signaling Pathways in the Mid Colon of SD Rats Via Complement C3 and its Receptors.

BACKGROUND: Complement component 3 (C3) receptors play an important role as inflammatory mediators in the innate immune system, although their mechanisms were not well studied during constipation. OBJECTIVE: The aim of this study is to investigate the regulatory role of C3 and its receptors' downstream signaling during constipation. METHODS: Alterations in the C3, C3a receptor (C3aR), and C3b receptor (C3bR) expressions, PI3K/AKT pathway, RhoA/MLC pathway, MAP kinase pathway, and inflammatory cytokine expressions were measured in the mid colon of loperamide (Lop) treated SD rats. RESULTS: Lop treatment successfully induced constipation phenotypes, including decreased stool parameters and histological structure alterations. The expression levels of C3 were significantly increased, whereas expressions of C3aR and C3bR were decreased during Lop-induced constipation. Moreover, significant upregulation was observed in the phosphorylation levels of PI3K, AKT, and GSK3ß in mid colons of Lop treated SD rats. The expression of RhoA and phosphorylation of MLC were also enhanced in the Lop treated group. Furthermore, a similar pattern was detected in the MAP kinase pathway and inflammatory cytokine expressions. Subsequent to the Lop treatment, the phosphorylation of ERK and p38, as well as the mRNA levels of NF-κB, TNF-α, IL-6 and IL-1α were remarkably increased in the mid colon. CONCLUSION: These results indicate that Lop-induced constipation is tightly linked to the downregulation of C3aR and C3bR expressions, and upregulation of the C3 and C3Rs downstream signaling pathway, including PI3K/AKT, RhoA/MLC, and MAP kinase pathways as well as inflammatory cytokine expressions in the mid colon of SD rats.

Evaluating Whether Radiofrequency Irradiation Attenuated UV-B-Induced Skin Pigmentation by Increasing Melanosomal Autophagy and Decreasing Melanin Synthesis.

Autophagy is involved in the degradation of melanosomes and the determination of skin color. TLR4 and tumor necrosis factor (TNF) signaling upregulates NF-kB expression, which is involved in the upregulation of mTOR. The activation of mTOR by UV-B exposure results in decreased autophagy, whereas radiofrequency (RF) irradiation decreases TLR4 and TNF receptor (TNFR) expression. We evaluated whether RF decreased skin pigmentation by restoring autophagy by decreasing the expression of TLR4 or TNFR/NF-κB/mTOR in the UV-B-irradiated animal model. UV-B radiation induced the expressions of TNFR, TLR, and NF-κB in the skin, which were all decreased by RF irradiation. RF irradiation also decreased phosphorylated mTOR expression and upregulated autophagy initiation factors such as FIP200, ULK1, ULK2, ATG13, and ATG101 in the UV-B-irradiated skin. Beclin 1 expression and the expression ratio of LC3-I to LC3-II were increased by UV-B/RF irradiation. Furthermore, melanin-containing autophagosomes increased with RF irradiation. Fontana-Masson staining showed that the amount of melanin deposition in the skin was decreased by RF irradiation. This study showed that RF irradiation decreased skin pigmentation by restoring melanosomal autophagy, and that the possible signal pathways which modulate autophagy could be TLR4, TNFR, NF-κB, and mTOR.

Azelaic Acid Promotes Caenorhabditis elegans Longevity at Low Temperature Via an Increase in Fatty Acid Desaturation.

PURPOSE: Azelaic acid (AzA) is a dicarboxylic acid naturally occurring in various grains having anti-inflammatory and anti-oxidation properties. Recently, AzA is shown to reduce high-fat diet-induced adiposity in animals. However, its physiological role in lipid metabolism and aging in various environmental stresses is unknown. METHODS AND RESULTS: Using C. elegans as an invertebrate animal model, we demonstrate that AzA suppresses fat accumulation with no effect on lifespan at normal temperatures. Moreover, AzA promotes lifespan at low temperatures by elevation of unsaturated long-chain fatty acids and expression of genes in fatty acid desaturation. We further find that genes encoding fatty acid desaturases such as fat-1, fat-5, fat-6, and fat-7 are crucial for the lifespan-extending effect of AzA at low temperature. CONCLUSIONS: Taken together, our results suggest that AzA promotes adaption to low temperature in C. elegans via shifting fatty acid profile to unsaturated long-chain fatty acids.

Anti-adipogenic effect of Lactobacillus fermentum MG4231 and MG4244 through AMPK pathway in 3T3-L1 preadipocytes.

This study evaluated the anti-adipogenic effects and mechanisms underlying the action of Lactobacillus fermentum MG4231 and MG4244 strains on adipogenesis and lipid accumulation in 3T3-L1 preadipocytes. Treatment with cell-free extracts (CFEs) from the two strains reduced lipid accumulation and intracellular triglyceride production in 3T3-L1 adipocytes by more than 50%. The inhibitory effects of L. fermentum on lipid accumulation were mediated by the downregulation of FAS and aP2 resulting from the inhibition of PPARγ and C/EBPα gene expression. Moreover, AMPK and HSL phosphorylation was upregulated by CFE treatment. These results indicated that the anti-adipogenic and lipolysis activities of L. fermentum strains were caused by increased AMPK and HSL phosphorylation. Both strains displayed high leucine arylamidase and ß-galactosidase enzymatic activity, with excellent adhesion to epithelial cells. Therefore, we identified L. fermentum as potential new probiotics for the prevention of obesity.

C. elegans ACAT regulates lipolysis and its related lifespan in fasting through modulation of the genes in lipolysis and insulin/IGF-1 signaling.

Overly active acyl-coenzyme A: cholesterol acyltransferases (ACATs) are known to contribute to the development of atherosclerosis, cancer cell proliferation and de novo lipogenesis. However, the role of ACAT in systemic lipid metabolism and its consequence of aging is unknown. Using avasimibe, a clinically proven ACAT inhibitor, and mboa-1 mutant strain, a homologous to mammalian ACAT, herein, we found that Ava treatment and mboa-1 mutant exhibited a decreased fat accumulation during feeding and increased lipolysis with extended lifespan of C. elegans during fasting. Our study highlights the essential role of ACAT inhibitor and mboa-1 in fat mobilization and the survival of C. elegans in fasting through the modulation of the genes involved in lipolysis and insulin/IGF-1 signaling.

Mori Cortex Radicis Attenuates High Fat Diet-Induced Cognitive Impairment via an IRS/Akt Signaling Pathway.

Present study was conducted to investigate ameliorating effects of Mori Cortex radicis on cognitive impair and neuronal defects in HFD-induced (High Fat Diet-Induced) obese mice. To induce obesity, C57BL/6 mice were fed an HFD for 8 weeks, and then mice were fed the HFD plus Mori Cortex radicis extract (MCR) (100 or 200 mg/kg/day) for 6 weeks. Prior to sacrifice, body weights were measured, and Y-maze test and oral glucose tolerance test were performed. Serum lipid metabolic biomarkers (TG, LDL, and HDL/total cholesterol ratio) and antioxidant enzymes (glutathione, superoxide dismutase, and catalase), malondialdehyde (MDA), and acetylcholinesterase (AChE) levels were measured in brain tissues. The expressions of proteins related to insulin signaling (p-IRS, PI3K, p-Akt, and GLUT4) and neuronal protection (p-Tau, Bcl-2, and Bax) were examined. MCR suppressed weight gain, improved serum lipid metabolic biomarker and glucose tolerance, inhibited AChE levels and MDA production, and restored antioxidant enzyme levels in brain tissue. In addition, MCR induced neuronal protective effects by inhibiting p-Tau expression and increasing Bcl-2/Bax ratio, which was attributed to insulin-induced increases in the expressions p-IRS, PI3K, p-Akt, and GLUT4. These indicate MCR may reduce HFD-induced insulin dysfunction and neuronal damage and suggest MCR be considered a functional material for the prevention of T2DM-associated neuronal disease.

Antioxidant Capacity of Thistle (Cirsium japonicum) in Various Drying Methods and their Protection Effect on Neuronal PC12 Cells and Caenorhabditis elegans.

The aim of this study was, firstly, to evaluate the phenol profile of thistle (Cirsium japonicum, CJ) by High performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS), dried by different methods (90 °C hot-air, 70 °C hot-air, shade-, and freeze-drying). Secondly, we aimed to evaluate the relationship between phenolic compounds content and antioxidant properties. CJ contained chlorogenic acid, linarin, and pectolinarin. Total phenolic contents of CJ significantly decreased under hot-air-drying condition, especially chlorogenic acid contents in CJ have been reduced by 85% and 60% for 90 °C and 70 °C hot-air-drying, respectively. We evaluated the protective effect on adrenal pheochromocytoma (PC12) cells and Caenorhabditis elegans using shade-dried CJ, which has the largest phenolic contents and the strongest antioxidant property. CJ-treated PC 12 cells dose-dependently exhibited the protective effects against reactive oxygen species (ROS), while cell viability increases, lactate dehydrogenase release decreases, and ROS formation decreases. Furthermore, CJ has also shown protection against ROS in C. elegans. Consequently, CJ contributed to lifespan extension under ROS stress without influencing the physiological growth.

PAC-5 Gene Expression Signature for Predicting Prognosis of Patients with Pancreatic Adenocarcinoma.

Pancreatic adenocarcinoma (PAC) is one of the most aggressive malignancies. Intratumoural molecular heterogeneity impedes improvement of the overall survival rate. Current pathological staging system is not sufficient to accurately predict prognostic outcomes. Thus, accurate prognostic model for patient survival and treatment decision is demanded. Using differentially expressed gene analysis between normal pancreas and PAC tissues, the cancer-specific genes were identified. A prognostic gene expression model was computed by LASSO regression analysis. The PAC-5 signature (LAMA3, E2F7, IFI44, SLC12A2, and LRIG1) that had significant prognostic value in the overall dataset was established, independently of the pathological stage. We provided evidence that the PAC-5 signature further refined the selection of the PAC patients who might benefit from postoperative therapies. SLC12A2 and LRIG1 interacted with the proteins that were implicated in resistance of EGFR kinase inhibitor. DNA methylation was significantly involved in the gene regulations of the PAC-5 signature. The PAC-5 signature provides new possibilities for improving the personalised therapeutic strategies. We suggest that the PAC-5 genes might be potential drug targets for PAC.

Phenolic components rich ethyl acetate fraction of Orostachys japonicus inhibits lipid accumulation by regulating reactive oxygen species generation in adipogenesis.

In this study, Orostachys japonicus was extracted with ethyl alcohol and fractionated by a serial of organic solvents. The ethyl acetate fraction was found to be the most effective among the tested five fractions. High-performance liquid chromatography and mass spectrometry analysis of the ethyl acetate fraction presented epicatechin gallate, quercetin-3-O-glucoside, and kaempferol-3-O-rutinoside. Treatment with O. japonicus inhibited reactive oxygen species (ROS) generation and lipid accumulation during adipogenesis. The gene expression of enzymes involved in the antioxidant system increased in O. japonicus-treated cells. messeanger RNA (mRNA) and protein expression of the pro-oxidant enzymes such as nicotinamide adenine dinucleotide phosphate hydrogen oxidase4 and glucose-6-phosphate dehydrogenase suppressed in O. japonicus-treated cells. O. japonicus also inhibited the mRNA and protein levels of adipogenic transcription factors (including proliferator activated receptor-γ and CCAAT/enhancer-binding protein-α) and their target gene (adipocyte protein 2). These results suggest that O. japonicus inhibits adipogenesis by controlling pro-/anti-oxidant enzyme responses and adipogenic transcription factors. PRACTICAL APPLICATIONS: ROS generation is markedly related to the pathogenesis and development of metabolic disorders. Treatment with O. japonicus inhibited ROS generation and lipid accumulation during adipogenesis. This result indicates that O. japonicus inhibit adipogenesis by controlling pro-/anti-oxidant enzyme responses and adipogenic mediators.

Inhibitory effects of Orostachys malacophyllus var. iwarenge extracts on reactive oxygen species production and lipid accumulation during 3T3-L1 adipocyte differentiation.

Orostachys malacophyllus var. iwarenge was extracted with water, 30 and 70% ethyl alcohol. The ethyl alcohol extracts showed higher total phenol contents and greater antioxidant effects than the water extract. Treatment with the 70% alcohol extract inhibited reactive oxygen species (ROS) production and lipid accumulation during 3T3-L1 adipogenesis. Furthermore, the 70% extract inhibited the mRNA and protein expressions of the pro-oxidant enzyme NADPH oxidase 4 and of the NADPH-producing enzyme glucose-6-phosphate dehydrogenase. The mRNA and protein expressions of antioxidant enzymes, such as copper-zinc superoxide dismutase and manganese superoxide dismutase increased in cells treated with the 70% alcohol extract. In addition, this extract suppressed the mRNA and protein levels of adipogenic transcription factors and of their marker genes. These results indicate that O. malacophyllus extracts inhibit lipid accumulation and ROS production by controlling adipogenic factors and pro-/anti-oxidant enzyme responses.

Midostaurin reduces Regulatory T cells markers in Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) is a heterogeneous hematological malignancy in which the only curative approach is allogeneic stem cell transplant (Allo-HSCT). The recognition and elimination of leukemic clones by donor T-cells contribute significantly to Allo-HSCT success. FLT3-ITD, a common mutation in AML, is associated with poor prognosis. Recently, midostaurin became the first FDA approved FLT3-inhibitor for pre-transplant patients with FLT3-ITD in combination with standard therapy. In addition to their multikinase activity which may affect T-cell signaling, FLT3-inhibitors induce apoptosis of malignant cells which may also enhance antigen presentation to activate T-cells. Considering the increased clinical use of these inhibitors in patients with AML, and the limited clinical benefit derived from their use as single agents, understanding how FLT3-inhibitors affect T cell population and function is needed to improve their clinical benefit. We examined the effect of four different FLT3 inhibitors (midostaurin, sorafenib, tandutinib, and quizartenib) on T cell populations in peripheral blood mononuclear cells (PBMC) obtained from healthy donors and from patients with AML. Midostaurin exhibited a significant decrease in CD4 + CD25 + FOXP3+ T cell population and FOXP3 mRNA expression in healthy and AML PBMCs. Similarly, samples collected from patients with AML treated with midostaurin showed a reduction in Tregs markers. Interferon-γ(IFN-γ), tumor necrosis factor-α(TNF-α), and IL-10 levels were also reduced following midostaurin treatment. Considering the FDA approval of midostaurin for use in patients with AML in the pre-transplant setting, our finding will have important clinical implication as it provides the rationale for functional investigation of the use of midostaurin in post-transplant patients.

Mitochondrial ROS-derived PTEN oxidation activates PI3K pathway for mTOR-induced myogenic autophagy.

Muscle differentiation is a crucial process controlling muscle development and homeostasis. Mitochondrial reactive oxygen species (mtROS) rapidly increase and function as critical cell signaling intermediates during the muscle differentiation. However, it has not yet been elucidated how they control myogenic signaling. Autophagy, a lysosome-mediated degradation pathway, is importantly recognized as intracellular remodeling mechanism of cellular organelles during muscle differentiation. Here, we demonstrated that the mtROS stimulated phosphatidylinositol 3 kinase/AKT/mammalian target of rapamycin (mTOR) cascade, and the activated mTORC1 subsequently induced autophagic signaling via phosphorylation of uncoordinated-51-like kinase 1 (ULK1) at serine 317 and upregulation of Atg proteins to prompt muscle differentiation. Treatment with MitoQ or rapamycin impaired both phosphorylation of ULK1 and expression of Atg proteins. Therefore, we propose a novel regulatory paradigm in which mtROS are required to initiate autophagic reconstruction of cellular organization through mTOR activation in muscle differentiation.