Tyrosine-phosphorylated SOCS3 negatively regulates cellular transformation mediated by the myeloproliferative neoplasm-associated JAK2 V617F mutant

In the majority of myeloproliferative neoplasms (MPNs) patients, a point mutation, V617F has been found in Janus kinase 2 (JAK2) gene, and this JAK2 mutant provoked aberrant signaling pathway. In the current study, we found that suppressor of cytokine signaling proteins 3 (SOCS3) possessed the tumor suppressive activity against the JAK2 V617F mutant-provoked cellular transformation. The knockdown of SOCS3 increased the expression level of the JAK2 V617F mutant, which enhanced the activation of signaling mediators, including signal transducer and activator of transcription 3 and 5 (STAT3, STAT5) and extracellular signal-regulated kinase (ERK), and also increased of the proliferation rate and tumorigenesis activity of Ba/F3 cells expressing the JAK2 V617F mutant and erythropoietin receptor (EpoR). In contrast, the enforced expression of SOCS3 significantly inhibited the JAK2 V617F mutant-induced activation of downstream signaling molecules, cell proliferation, and tumorigenesis by down-regulating the expression level of the JAK2 V617F mutant. SOCS3 interacted with the JAK2V617F mutant through its SH2 domain and was phosphorylated at Tyr-204 and Tyr-221 in its SOCS box by the JAK2V617F mutant. SOCS3 mutants carrying a mutation in the SH2 domain (R71E) and a substitution at Tyr-221 (Y221F) failed to exert inhibitory effects on JAK2V617F mutant-induced cellular transformation and tumorigenesis. Collectively, these results imply that SOCS3 plays a negative role in the JAK2 V617F mutant-induced oncogenic signaling pathway through its SH2 domain and the phosphorylation of Tyr-221 in its SOCS box.

Coffee brew intake can prevent the reduction of lens glutathione and ascorbic acid levels in HFD-fed animals

The lens has high concentrations of glutathione (GSH) and ascorbic acid (AsA) to maintain redox activity and prevent cataract formation, which is the leading cause of visual impairment worldwide. Metabolic syndrome is reported to be linked with a higher risk of age-associated cataract. As it was demonstrated previously that coffee consumption improved high-fat diet (HFD) -induced metabolic symptoms, it was hypothesized that coffee intake could delay the onset of obesity related-cataract; however, the effect of coffee consumption on this type of cataract remains unknown. Four-week-old male C57BL/6JJms SLC mice were divided into two groups and were provided ad libitum access to either a control diet (control groups) or a HFD (HFD groups). The control groups and HFD groups were further divided into three or four subgroups for each experiment. Coffee intake markedly reduced the increase in body weight in a roasting-time and concentration-dependent manner. Coffee consumption also prevented the HFD-induced decrease in the concentration of GSH and AsA, and treatment with pyrocatechol or caffeine also restored the reduction of antioxidant compounds. Plasma cholesterol and triglycerides were significantly higher in HFD groups; however, coffee brew or coffee constituent treatment in the HFD-fed mice group prevented elevation of these levels. Caffeine is a major coffee component and pyrocatechol is generated thought the roasting process. These results revealed that caffeine and pyrocatechol in coffee brew may be the key constituents responsible for preventing the reduction of lens GSH and AsA in HFD-fed animals.

Estimating the Net Utility Gains Among Donors and Recipients of Adult Living Donor Kidney Transplant

OBJECTIVES

Living donor kidney transplant relieves the disease burden of patients with end-stage renal disease but may shorten donor life expectancy; however, their quality of life (QOL) is preserved. Nevertheless, the magnitude of the net gain of this procedure is unknown. We evaluated the QOL of both donors and recipients concurrently and calculated the net utility gain.

METHODS

We recruited 210 subjects who visited the kidney transplantation clinic of a university hospital. Subjects were asked to complete the 5-level EQ-5D-based questionnaire, and patient characteristics were extracted from their medical records. We performed multivariate tobit models analysis to evaluate the QOL change caused by transplant surgery and subsequently ran computational simulations to determine the net utility gains of donors and recipients. We also performed sensitivity analyses.

RESULTS

After excluding 16 answers with missing data, we analyzed 203 answers in total. After the transplant surgery, recipients gained 0.07 in utility value while donors lost 0.04. In the net utility analysis, we found that the quality-adjusted life years gained ranged from 7.2 to 7.8 in the most favorable case observed in the combination of middle-aged recipients and elderly donors. Assuming no utility discount, the most favorable combination was that with older donors and younger recipients.

CONCLUSIONS

These findings indicated that the QOL improvement in recipients was larger than the loss among donors. When calculating the net utilities, a combination of middle-aged recipients and elderly donors yielded the largest net utility, but this was likely derived from assumption in the discount of QOL.

Chemoenzymatic synthesis of hydroxytyrosol monoesters and their suppression effect on nitric oxide production stimulated by lipopolysaccharides

Fatty acid monoesters of hydroxytyrosol [2-(3,4-dihydroxyphenyl)ethanol] were synthesized in two steps from tyrosol (4-hydroxyphenylethanol) by successive Candida antarctica lipase B-catalyzed chemoselective acylation on the primary aliphatic hydroxy group over phenolic hydroxy group in tyrosol, and 2-iodoxybenzoic acid (IBX)-mediated hydroxylation adjacent to the remaining free phenolic hydroxy group. Examination of their suppression effects on nitric oxide production stimulated by lipopolysaccharides in RAW264.7 cells showed that hydroxytyrosol butyrate exhibited the highest inhibition (IC₅₀ 7.0 μM) among the tested compounds.

Roasted Coffee Reduces β-Amyloid Production by Increasing Proteasomal β-Secretase Degradation in Human Neuroblastoma SH-SY5Y Cells

SCOPE

Epidemiological studies have shown that coffee consumption may be associated with a lower risk of developing several neurological disorders, including Alzheimer's disease (AD). Caffeine is a prominent candidate component underlying the preventive effects of coffee; however, the contribution of other constituents is unclear. To clarify this issue, the effect of roasting coffee beans on β-secretase (BACE1) expression in human neuroblastoma SH-SY5Y cells is investigated.

METHODS AND RESULTS

Coffee (2%) reduces Aβ accumulation in culture medium to 80% of control levels after 24 h. Accordingly, BACE1 expression is decreased to 70% of control levels at 12 h. Experiments using cycloheximide and MG132, a proteasome inhibitor, reveal that coffee enhanced BACE1 degradation through activation of proteasomal activity. Furthermore, coffee activates cAMP-dependent protein kinase, and consequently, phosphorylation of a serine residue of proteasome 26S subunit, non-ATPase 11 (PSMD11). Pyrocatechol, a strong antioxidant known as catechol or 1,2-dihydroxybenzene, produced from chlorogenic acid during roasting, also reduces BACE1 expression by activation of proteasomal activity. Furthermore, pyrocatechol reduces Aβ production in SH-SY5Y cells.

CONCLUSION

The data suggest that the roasting process may be crucial for the protective effects of coffee consumption in AD.

Hydroxytyrosol butyrate inhibits 6-OHDA-induced apoptosis through activation of the Nrf2/HO-1 axis in SH-SY5Y cells

Hydroxytyrosol (HT) is a polyphenol contained in olives and exhibits antioxidant activity. We herein investigated the effects of HT and its derivatives, hydroxytyrosol acetate (HT-A) and hydroxytyrosol butyrate (HT-B), on the protection of neuronal cells against apoptosis induced by the Parkinson's disease-related neurotoxin 6-hydroxydopamine (6-OHDA). The pretreatment of SH-SY5Y cells with HT-B, but not HT or HT-A significantly reduced the 6-OHDA-induced generation of reactive oxygen species, activation of caspase-3, and subsequent cell death. HT-B also induced the protein expression of the transcription factor, NF-E2-related factor-2 (Nrf2) and its transcriptional activation, resulting in the up-regulated expression of heme oxygenase-1 (HO-1), which conferred neuroprotection against 6-OHDA-induced oxidative damage. Furthermore, three cysteine residues, Cys151, Cys273, and Cys288 in Kelch-like ECH-associated protein 1 (Keap1) were necessary for the HT-B-induced activation of Nrf2. Collectively, the present results demonstrated that HT-B, harboring higher fat solubility than HT and HT-A, effectively elicited adaptive responses to oxidative stress by activating the Nrf2/HO-1 axis in neuronal cells.

Effect of hesperetin derivatives on the development of selenite‑induced cataracts in rats

Cataracts are a major cause of blindness worldwide. As anti‑cataract pharmaceutical therapies require long‑term treatment, identifying anti‑cataract compounds that are ubiquitous in the human diet, have no adverse effects and are affordable, is of paramount importance. The present study focused on hesperetin and its derived compounds, hesperetin stearic acid ester (Hes‑S) and hesperetin oleic acid ester (Hes‑O), in order to investigate their therapeutic potential to treat cataracts in a selenite animal model. Thirteen‑day‑old Sprague Dawley rats were divided into 12 groups. Animals in groups 1 and 7 were subcutaneously injected with vehicle, those in groups 2 and 8 were administered hesperetin, those in groups 3 and 9 received stearic acid, those in groups 4 and 10 were injected with oleic acid, those in groups 5 and 11 were administered Hes‑S, and those in groups 6 and 12 received Hes‑O (10 nmol/kg body weight on days 0, 1 and 2). Animals in groups 7 to 12 were treated with sodium selenite (20 µmol/kg body weight given 4 h following the test compound treatment on day 0) to induce cataract. On day 6, rats had less severe central opacities and lower stage cataracts than rats in the selenite treatment‑only control groups. The levels of glutathione (GSH) and ascorbic acid (AsA) in lenses with selenite‑induced cataracts declined to one‑third of that of controls, and the reduction in GSH and AsA levels was rescued following hesperetin, Hes‑S or Hes‑O treatment, with concentrations remaining to 70‑80% of that of controls. However, there were no changes in the plasma levels of GSH and AsA following treatments. Administration of either hesperetin or hesperetin‑derived compounds prevented the reduction of chaperone activity in the lens, and rats treated with Hes‑S or Hes‑O treatment had significantly greater chaperone activity than hesperetin‑treated rats. Collectively, these results suggested that hesperetin and hesperetin‑derived compounds may be novel drug compounds that have the potential to prevent or delay the onset of cataracts.

A major component of vitamin E, α-tocopherol inhibits the anti-tumor activity of crizotinib against cells transformed by EML4-ALK

Crizotinib is an inhibitor of anaplastic lymphoma kinase (ALK) and is of significant therapeutic benefit to patients with non-small cell lung cancer (NSCLC) harboring the EML4-ALK fusion gene. In the present study, we demonstrated that α-tocopherol, a major component of vitamin E, attenuated the effects of crizotinib independently of its anti-oxidant properties. α-Tocopherol significantly inhibited crizotinib-induced apoptosis in cells transformed by EML4-ALK. It also effectively attenuated the crizotinib-induced inhibition of EML4-ALK and its downstream molecules, STAT3 and ERK, and suppressed the inhibitory effects of crizotinib on EML4-ALK-mediated transformation in the focus formation assay. On the other hand, other members of the vitamin E family, namely, β-tocopherol, γ-tocopherol, δ-tocopherol, and α-tocotrienol, and a water-soluble analog of vitamin E, Trolox had no effects on the anti-tumor activity of crizotinib in cells transformed by EML4-ALK. Collectively, these results revealed the risk of the anti-tumor activity of crizotinib being attenuated when it is administrated in combination with vitamin E supplements containing α-tocopherol as a major component.

First Determination of the Level Structure of an sd-Shell Hypernucleus, _{Λ}^{19}F

We report on the first observation of γ rays emitted from an sd-shell hypernucleus, _{Λ}^{19}F. The energy spacing between the ground state doublet, 1/2^{+} and 3/2^{+} states, of _{Λ}^{19}F is determined to be 315.5±0.4(stat)_{-0.5}^{+0.6}(syst)  keV by measuring the γ-ray energy of the M1(3/2^{+}→1/2^{+}) transition. In addition, three γ-ray peaks are observed and assigned as E2(5/2^{+}→1/2^{+}), E1(1/2^{-}→1/2^{+}), and E1(1/2^{-}→3/2^{+}) transitions. The excitation energies of the 5/2^{+} and 1/2^{-} states are determined to be 895.2±0.3(stat)±0.5(syst) and 1265.6±1.2(stat)_{-0.5}^{+0.7}(syst)  keV, respectively. It is found that the ground state doublet spacing is well described by theoretical models based on existing s- and p-shell hypernuclear data.

Robust singlet fission in pentacene thin films with tuned charge transfer interactions

Singlet fission, the spin-allowed photophysical process converting an excited singlet state into two triplet states, has attracted significant attention for device applications. Research so far has focused mainly on the understanding of singlet fission in pure materials, yet blends offer the promise of a controlled tuning of intermolecular interactions, impacting singlet fission efficiencies. Here we report a study of singlet fission in mixtures of pentacene with weakly interacting spacer molecules. Comparison of experimentally determined stationary optical properties and theoretical calculations indicates a reduction of charge-transfer interactions between pentacene molecules with increasing spacer molecule fraction. Theory predicts that the reduced interactions slow down singlet fission in these blends, but surprisingly we find that singlet fission occurs on a timescale comparable to that in pure crystalline pentacene. We explain the observed robustness of singlet fission in such mixed films by a mechanism of exciton diffusion to hot spots with closer intermolecular spacings.

Efficient Signal Processing of Multineuronal Activities for Neural Interface and Prosthesis

Objectives : Multineuronal spike trains must be efficiently decoded in order to utilize them for controlling artificial limbs and organs. Here we evaluated the efficiency of pooling (averaging) and combining (vectorizing) activities of multiple neurons for decoding neuronal information.

Methods : Multineuronal activities in the monkey inferior temporal (IT) cortex were obtained by classifying spikes of constituent neurons from multichannel data recorded with a multisite microelectrode. We compared pooling and combining procedures for the amount of visual information transferred by neurons, and for the success rate of stimulus estimation based on neuronal activities in each trial.

Results : Both pooling and combining activities of multiple neurons increased the amount of information and the success rate with the number of neurons. However, the degree of improvement obtained by increasing the number of neurons was higher when combining activities as opposed to pooling them.

Conclusion: Combining the activities of multiple neurons is more efficient than pooling them for obtaining a precise interpretation of neuronal signals.