Hydrogen gas reduces ischemia and reperfusion injury (IRI) in the liver and other organs. However... more Hydrogen gas reduces ischemia and reperfusion injury (IRI) in the liver and other organs. However, the precise mechanism remains elusive. We investigated whether hydrogen gas ameliorated hepatic I/R injury after cold preservation. Rat liver was subjected to 48-h cold storage in University of Wisconsin solution. The graft was reperfused with oxygenated buffer with or without hydrogen at 37° for 90 min on an isolated perfusion apparatus, comprising the H2 (+) and H2 (-) groups, respectively. In the control group (CT), grafts were reperfused immediately without preservation. Graft function, injury, and circulatory status were assessed throughout the perfusion. Tissue samples at the end of perfusion were collected to determine histopathology, oxidative stress, and apoptosis. In the H2 (-) group, IRI was indicated by a higher aspartate aminotransferase (AST), alanine aminotransferase (ALT) leakage, portal resistance, 8-hydroxy-2-deoxyguanosine-positive cell rate, apoptotic index, and end...
β‐Amyloid precursor protein (APP) has been reported to be expressed in the CNS from the early sta... more β‐Amyloid precursor protein (APP) has been reported to be expressed in the CNS from the early stages of development. However, the functional role of APP during early development remains unclear. In the present study, we found that the secreted form of APP (sAPP) significantly enhanced proliferation of neural stem cells. Cells were prepared from 13‐day embryonic rat neocortex, which was dissected with a Pasteur pipette to make cell clusters. After 12 h of cultivation in the medium without serum, cells around the centre of the cluster were still nestin‐positive proliferative cells, i.e. neural stem cells. To determine whether the proliferation of cells was regulated by sAPP, cultures were treated with recombinant sAPP695, the secreted form of human APP695 produced by yeast. Both DNA synthesis and expression of proliferating cell nuclear antigen markedly increased after 5 h of sAPP695 addition. The enhancement of DNA synthesis by sAPP695 stimulation was blocked by the 22C11 monoclonal ...
The reaction system for the bioconversion of dethiobiotin into biotin by resting cells and protop... more The reaction system for the bioconversion of dethiobiotin into biotin by resting cells and protoplasts of a Bacillus sphaericus bioB transformant was established. The reaction mixtures consisted of completely synthetic components, such as amino acids and metal salts. Among the sulfur compounds tested, L-CyS and L-cystine were effective in the biosynthesis of biotin from dethiobiotin both by resting cells and by protoplasts. The optimum concentrations of L-Cys were 2 to 3 mM and more than 0.25 mM for resting cell and protoplast systems, respectively. Vigorous shaking enhanced the biotin biosynthesis by protoplasts. The addition of yeast extract to the reaction mixture without a mixture of amino acids brought about a three-fold increase in the, amount of biotin synthesized by protoplasts when compard to the case with the reaction mixture containing the amino acid mixture. The amount of biotin synthesized by protoplasts increased with the incubation time up to 6 h and reached about 2 μg/ml. There was a clear...
December 2008.We used data on prescription of nearly three million inhabitants from the Drug Admi... more December 2008.We used data on prescription of nearly three million inhabitants from the Drug Administrative Lombardy Region Database. Data of first prescription of one ChEI was used as the index-day to calculate the co-prescribing of an antipsychotic. Results: There were 543,000 people aged 65 years or older, 60% women; the mean age was 75.1 (+/-7.2) years. The prevalence of individuals who received at least one prescription for ChEIs rose from 0.5% in 2002 to 0.7% in 2004, reaching a plateau that was roughly stable until 2008, with no difference between sex. Figure 1 shows the co-prescribing trend of antipsychotics in patients exposed to ChEIs. While the prevalence of elderly receiving a co-prescription of atypical antipsychotics declined from 21% in 2002 to 14% in 2007 (chi-squared test for trend, p<0.0001), the prescribing prevalence of typicals showed a mild increase (chi-squared test for trend, p< 0.0001). Atypical antipsychotics were four times more prescribed than typicals. No difference in co-prescribing trend was found for sex and age. The decline in 2004 and 2006 for a typicals is probably due to the official warnings issued by the Italian Drug Agency to restrict the use of antipsychotics in elderly with dementia because the risk of serious adverse reactions. Conclusions: Although two warnings issued to discourage the use of antipsychotics and numerous publications concerning the safety of these drugs, their prescription is still high in patients taking ChEIs. Awaiting further studies for clarifying their therapeutic role, physicians should prescribe antipsychotics most cautiously and only after a careful risk-benefit evaluation.
Additional file 3. The original, full-length western blot images of fibronectin, αSMA, GAPDH, COL... more Additional file 3. The original, full-length western blot images of fibronectin, αSMA, GAPDH, COL1, TGF-β1 and β-actin.
Biochemical and Biophysical Research Communications, 2021
Mitochondrial dysfunction is considered to be a major cause of sarcopenia, defined as age-related... more Mitochondrial dysfunction is considered to be a major cause of sarcopenia, defined as age-related muscle fiber atrophy and muscle weakness, as reduced mitochondrial respiration and morphological changes such as ragged red fibers (RRFs) are observed in aging muscles. However, the role of mitochondrial dysfunction in sarcopenia is not fully elucidated. Although previous studies have suggested that aging has a fiber type-specific effect on mitochondrial function, little is known about mitochondrial changes in individual fiber types. Here, we used C57BL/6NCr female mice to identify fiber type-specific pathological changes, examine the significance of pathological changes in sarcopenia, and identify possible mechanisms behind mitochondrial changes in slow-twitch soleus muscle (SOL) and fast-twitch extensor digitorum longus muscle (EDL). We observed reduced type I fiber-specific mitochondrial respiratory enzyme activity, impaired respiration, and subsarcolemmal mitochondrial accumulation in aged SOL, which was different from RRFs. These pathological alterations were not directly associated with fiber atrophy. Additionally, we found increased oxidative stress markers in aged SOL, suggesting that oxidative stress is involved in the pathological and functional changes in mitochondria. Meanwhile, obvious mitochondrial changes were not seen in aged EDL. Thus, age-related mitochondrial dysfunction is specific to the fiber type and may correlate with the muscle quality rather than the muscle mass.
<jats:p> [Introduction] Despite an increase in the levels of aldehydes, the heart from alde... more <jats:p> [Introduction] Despite an increase in the levels of aldehydes, the heart from aldehyde dehydrogenase ( <jats:italic>ALDH</jats:italic> ) <jats:italic>2*2</jats:italic> -transgenic (Tg) mice, loss of function model of ALDH, exhibited a greater tolerance to oxidative stress via activation of amino acid metabolism leading to glutathione biosynthesis. This study was designed to identify the signaling cascades responsible for the activation of amino acid metabolism by aldehydes. [Methods &amp; Results] (1) Phosphorylation of <jats:italic>α</jats:italic> -subunit of eukaryotic translation initiation factor 2 (eIF2 <jats:italic>α</jats:italic> ) and subsequent translational activation of ATF4 have been shown to induce amino acid metabolism as a common response to a wide variety of stressors. Consistent with this, phosphorylation levels of eIF2 <jats:italic>α</jats:italic> and protein expression of ATF4 were increased in <jats:italic>ALDH2*2</jats:italic> -Tg hearts. (2) Among four eIF2 <jats:italic>α</jats:italic> kinases, general control non-depressible (GCN)2 kinase, a sensor for amino acid insufficiency, was activated in <jats:italic>ALDH2*2</jats:italic> -Tg heart. (3) Quantification of intracellular amino acid demonstrated that free histidine concentration in <jats:italic>ALDH2*2</jats:italic> -Tg heart was selectively reduced by 50% compared to that in non-Tg littermates. (4) To clarify the functional significance of observed reduction in histidine, <jats:italic>ALDH2*2</jats:italic> -Tg mice were fed a high histidine diet. The phosphorylation levels of eIF2 <jats:italic>α</jats:italic> and the protein levels of ATF4 were diminished by 50% in <jats:italic>ALDH2*2</jats:italic> -Tg mice fed the high histidine diet, in agreement with the normalization of histidine concentration. Accordingly, both enhanced tolerance to ischemia-reperfusion injury and elevated levels of glutathione were partially diminished in the heart from <jats:italic>ALDH2*2</jats:italic> -Tg mice fed the high histidine diet compared to <jats:italic>ALDH2*2</jats:italic> -Tg mice fed normal chow. (5) In culture, exposure to 4-hydroxy-2-nonenal (4-HNE) phosphorylated GCN2 and eIF2 <jats:italic>α</jats:italic> and increased protein levels of ATF4 in a time-dependent manner. (6) siRNA-mediated knockdown of GCN2 abrogated 4-HNE-induced induction of amino acid metabolic genes. [Conclusions] Activation of eIF2 <jats:italic>α</jats:italic> -ATF4 pathway via GCN2 kinase might be of special importance in the transcriptional control that coordinately promotes amino acid metabolism in response to aldehydes. Intracellular depletion of free histidine is at least partly involved in the activation of GCN2 kinase by aldehydes. </jats:p>
Vertebrate animals detect odors through olfactory receptors (ORs), members of the G protein-coupl... more Vertebrate animals detect odors through olfactory receptors (ORs), members of the G protein-coupled receptor (GPCR) family. Due to the difficulty in the heterologous expression of ORs, studies of their odor molecule recognition mechanisms have progressed poorly. Functional expression of most ORs in heterologous cells requires the co-expression of their chaperone proteins, receptor transporting proteins (RTPs). Yet, some ORs were found to be functionally expressed without the support of RTP (RTP-independent ORs). In this study, we investigated whether amino acid residues highly conserved among RTP-independent ORs improve the functional expression of ORs in heterologous cells. We found that a single amino acid substitution at one of two sites (NBW3.39 and 3.43) in their conserved residues (E and L, respectively) significantly improved the functional expression of ORs in heterologous cells. E3.39 and L3.43 also enhanced the membrane expression of RTP-dependent ORs in the absence of RTP...
Background Acute respiratory distress syndrome, which is caused by acute lung injury, is a destru... more Background Acute respiratory distress syndrome, which is caused by acute lung injury, is a destructive respiratory disorder caused by a systemic inflammatory response. Persistent inflammation results in irreversible alveolar fibrosis. Because hydrogen gas possesses anti-inflammatory properties, we hypothesized that daily repeated inhalation of hydrogen gas could suppress persistent lung inflammation by inducing functional changes in macrophages, and consequently inhibit lung fibrosis during late-phase lung injury. Methods To test this hypothesis, lung injury was induced in mice by intratracheal administration of bleomycin (1.0 mg/kg). Mice were exposed to control gas (air) or hydrogen (3.2% in air) for 6 h every day for 7 or 21 days. Respiratory physiology, tissue pathology, markers of inflammation, and macrophage phenotypes were examined. Results Mice with bleomycin-induced lung injury that received daily hydrogen therapy for 21 days (BH group) exhibited higher static compliance (0...
Because multicellular organisms do not have hydrogenase, H2 has been considered to be biologicall... more Because multicellular organisms do not have hydrogenase, H2 has been considered to be biologically inactive in these species, and enterobacteria to be largely responsible for the oxidation of H2 taken into the body. However, we showed previously that inhalation of H2 markedly suppresses brain injury induced by focal ischemia-reperfusion by buffering oxidative stress. Although the reaction constant of H2 with hydroxyl radical in aqueous solution is two to three orders of magnitude lower than that of conventional antioxidants, we showed that hydroxyl radical generated by the Fenton reaction reacts with H2 at room temperature without a catalyst. Suppression of hydroxyl radical by H2 has been applied in ophthalmic surgery. However, many of the anti- inflammatory and other therapeutic effects of H2 cannot be completely explained by its ability to scavenge reactive oxygen species. H2 administration is protective in several disease models, and preculture in the presence of H2 suppresses ox...
Hydrogen gas reduces ischemia and reperfusion injury (IRI) in the liver and other organs. However... more Hydrogen gas reduces ischemia and reperfusion injury (IRI) in the liver and other organs. However, the precise mechanism remains elusive. We investigated whether hydrogen gas ameliorated hepatic I/R injury after cold preservation. Rat liver was subjected to 48-h cold storage in University of Wisconsin solution. The graft was reperfused with oxygenated buffer with or without hydrogen at 37° for 90 min on an isolated perfusion apparatus, comprising the H2 (+) and H2 (-) groups, respectively. In the control group (CT), grafts were reperfused immediately without preservation. Graft function, injury, and circulatory status were assessed throughout the perfusion. Tissue samples at the end of perfusion were collected to determine histopathology, oxidative stress, and apoptosis. In the H2 (-) group, IRI was indicated by a higher aspartate aminotransferase (AST), alanine aminotransferase (ALT) leakage, portal resistance, 8-hydroxy-2-deoxyguanosine-positive cell rate, apoptotic index, and end...
β‐Amyloid precursor protein (APP) has been reported to be expressed in the CNS from the early sta... more β‐Amyloid precursor protein (APP) has been reported to be expressed in the CNS from the early stages of development. However, the functional role of APP during early development remains unclear. In the present study, we found that the secreted form of APP (sAPP) significantly enhanced proliferation of neural stem cells. Cells were prepared from 13‐day embryonic rat neocortex, which was dissected with a Pasteur pipette to make cell clusters. After 12 h of cultivation in the medium without serum, cells around the centre of the cluster were still nestin‐positive proliferative cells, i.e. neural stem cells. To determine whether the proliferation of cells was regulated by sAPP, cultures were treated with recombinant sAPP695, the secreted form of human APP695 produced by yeast. Both DNA synthesis and expression of proliferating cell nuclear antigen markedly increased after 5 h of sAPP695 addition. The enhancement of DNA synthesis by sAPP695 stimulation was blocked by the 22C11 monoclonal ...
The reaction system for the bioconversion of dethiobiotin into biotin by resting cells and protop... more The reaction system for the bioconversion of dethiobiotin into biotin by resting cells and protoplasts of a Bacillus sphaericus bioB transformant was established. The reaction mixtures consisted of completely synthetic components, such as amino acids and metal salts. Among the sulfur compounds tested, L-CyS and L-cystine were effective in the biosynthesis of biotin from dethiobiotin both by resting cells and by protoplasts. The optimum concentrations of L-Cys were 2 to 3 mM and more than 0.25 mM for resting cell and protoplast systems, respectively. Vigorous shaking enhanced the biotin biosynthesis by protoplasts. The addition of yeast extract to the reaction mixture without a mixture of amino acids brought about a three-fold increase in the, amount of biotin synthesized by protoplasts when compard to the case with the reaction mixture containing the amino acid mixture. The amount of biotin synthesized by protoplasts increased with the incubation time up to 6 h and reached about 2 μg/ml. There was a clear...
December 2008.We used data on prescription of nearly three million inhabitants from the Drug Admi... more December 2008.We used data on prescription of nearly three million inhabitants from the Drug Administrative Lombardy Region Database. Data of first prescription of one ChEI was used as the index-day to calculate the co-prescribing of an antipsychotic. Results: There were 543,000 people aged 65 years or older, 60% women; the mean age was 75.1 (+/-7.2) years. The prevalence of individuals who received at least one prescription for ChEIs rose from 0.5% in 2002 to 0.7% in 2004, reaching a plateau that was roughly stable until 2008, with no difference between sex. Figure 1 shows the co-prescribing trend of antipsychotics in patients exposed to ChEIs. While the prevalence of elderly receiving a co-prescription of atypical antipsychotics declined from 21% in 2002 to 14% in 2007 (chi-squared test for trend, p<0.0001), the prescribing prevalence of typicals showed a mild increase (chi-squared test for trend, p< 0.0001). Atypical antipsychotics were four times more prescribed than typicals. No difference in co-prescribing trend was found for sex and age. The decline in 2004 and 2006 for a typicals is probably due to the official warnings issued by the Italian Drug Agency to restrict the use of antipsychotics in elderly with dementia because the risk of serious adverse reactions. Conclusions: Although two warnings issued to discourage the use of antipsychotics and numerous publications concerning the safety of these drugs, their prescription is still high in patients taking ChEIs. Awaiting further studies for clarifying their therapeutic role, physicians should prescribe antipsychotics most cautiously and only after a careful risk-benefit evaluation.
Additional file 3. The original, full-length western blot images of fibronectin, αSMA, GAPDH, COL... more Additional file 3. The original, full-length western blot images of fibronectin, αSMA, GAPDH, COL1, TGF-β1 and β-actin.
Biochemical and Biophysical Research Communications, 2021
Mitochondrial dysfunction is considered to be a major cause of sarcopenia, defined as age-related... more Mitochondrial dysfunction is considered to be a major cause of sarcopenia, defined as age-related muscle fiber atrophy and muscle weakness, as reduced mitochondrial respiration and morphological changes such as ragged red fibers (RRFs) are observed in aging muscles. However, the role of mitochondrial dysfunction in sarcopenia is not fully elucidated. Although previous studies have suggested that aging has a fiber type-specific effect on mitochondrial function, little is known about mitochondrial changes in individual fiber types. Here, we used C57BL/6NCr female mice to identify fiber type-specific pathological changes, examine the significance of pathological changes in sarcopenia, and identify possible mechanisms behind mitochondrial changes in slow-twitch soleus muscle (SOL) and fast-twitch extensor digitorum longus muscle (EDL). We observed reduced type I fiber-specific mitochondrial respiratory enzyme activity, impaired respiration, and subsarcolemmal mitochondrial accumulation in aged SOL, which was different from RRFs. These pathological alterations were not directly associated with fiber atrophy. Additionally, we found increased oxidative stress markers in aged SOL, suggesting that oxidative stress is involved in the pathological and functional changes in mitochondria. Meanwhile, obvious mitochondrial changes were not seen in aged EDL. Thus, age-related mitochondrial dysfunction is specific to the fiber type and may correlate with the muscle quality rather than the muscle mass.
<jats:p> [Introduction] Despite an increase in the levels of aldehydes, the heart from alde... more <jats:p> [Introduction] Despite an increase in the levels of aldehydes, the heart from aldehyde dehydrogenase ( <jats:italic>ALDH</jats:italic> ) <jats:italic>2*2</jats:italic> -transgenic (Tg) mice, loss of function model of ALDH, exhibited a greater tolerance to oxidative stress via activation of amino acid metabolism leading to glutathione biosynthesis. This study was designed to identify the signaling cascades responsible for the activation of amino acid metabolism by aldehydes. [Methods &amp; Results] (1) Phosphorylation of <jats:italic>α</jats:italic> -subunit of eukaryotic translation initiation factor 2 (eIF2 <jats:italic>α</jats:italic> ) and subsequent translational activation of ATF4 have been shown to induce amino acid metabolism as a common response to a wide variety of stressors. Consistent with this, phosphorylation levels of eIF2 <jats:italic>α</jats:italic> and protein expression of ATF4 were increased in <jats:italic>ALDH2*2</jats:italic> -Tg hearts. (2) Among four eIF2 <jats:italic>α</jats:italic> kinases, general control non-depressible (GCN)2 kinase, a sensor for amino acid insufficiency, was activated in <jats:italic>ALDH2*2</jats:italic> -Tg heart. (3) Quantification of intracellular amino acid demonstrated that free histidine concentration in <jats:italic>ALDH2*2</jats:italic> -Tg heart was selectively reduced by 50% compared to that in non-Tg littermates. (4) To clarify the functional significance of observed reduction in histidine, <jats:italic>ALDH2*2</jats:italic> -Tg mice were fed a high histidine diet. The phosphorylation levels of eIF2 <jats:italic>α</jats:italic> and the protein levels of ATF4 were diminished by 50% in <jats:italic>ALDH2*2</jats:italic> -Tg mice fed the high histidine diet, in agreement with the normalization of histidine concentration. Accordingly, both enhanced tolerance to ischemia-reperfusion injury and elevated levels of glutathione were partially diminished in the heart from <jats:italic>ALDH2*2</jats:italic> -Tg mice fed the high histidine diet compared to <jats:italic>ALDH2*2</jats:italic> -Tg mice fed normal chow. (5) In culture, exposure to 4-hydroxy-2-nonenal (4-HNE) phosphorylated GCN2 and eIF2 <jats:italic>α</jats:italic> and increased protein levels of ATF4 in a time-dependent manner. (6) siRNA-mediated knockdown of GCN2 abrogated 4-HNE-induced induction of amino acid metabolic genes. [Conclusions] Activation of eIF2 <jats:italic>α</jats:italic> -ATF4 pathway via GCN2 kinase might be of special importance in the transcriptional control that coordinately promotes amino acid metabolism in response to aldehydes. Intracellular depletion of free histidine is at least partly involved in the activation of GCN2 kinase by aldehydes. </jats:p>
Vertebrate animals detect odors through olfactory receptors (ORs), members of the G protein-coupl... more Vertebrate animals detect odors through olfactory receptors (ORs), members of the G protein-coupled receptor (GPCR) family. Due to the difficulty in the heterologous expression of ORs, studies of their odor molecule recognition mechanisms have progressed poorly. Functional expression of most ORs in heterologous cells requires the co-expression of their chaperone proteins, receptor transporting proteins (RTPs). Yet, some ORs were found to be functionally expressed without the support of RTP (RTP-independent ORs). In this study, we investigated whether amino acid residues highly conserved among RTP-independent ORs improve the functional expression of ORs in heterologous cells. We found that a single amino acid substitution at one of two sites (NBW3.39 and 3.43) in their conserved residues (E and L, respectively) significantly improved the functional expression of ORs in heterologous cells. E3.39 and L3.43 also enhanced the membrane expression of RTP-dependent ORs in the absence of RTP...
Background Acute respiratory distress syndrome, which is caused by acute lung injury, is a destru... more Background Acute respiratory distress syndrome, which is caused by acute lung injury, is a destructive respiratory disorder caused by a systemic inflammatory response. Persistent inflammation results in irreversible alveolar fibrosis. Because hydrogen gas possesses anti-inflammatory properties, we hypothesized that daily repeated inhalation of hydrogen gas could suppress persistent lung inflammation by inducing functional changes in macrophages, and consequently inhibit lung fibrosis during late-phase lung injury. Methods To test this hypothesis, lung injury was induced in mice by intratracheal administration of bleomycin (1.0 mg/kg). Mice were exposed to control gas (air) or hydrogen (3.2% in air) for 6 h every day for 7 or 21 days. Respiratory physiology, tissue pathology, markers of inflammation, and macrophage phenotypes were examined. Results Mice with bleomycin-induced lung injury that received daily hydrogen therapy for 21 days (BH group) exhibited higher static compliance (0...
Because multicellular organisms do not have hydrogenase, H2 has been considered to be biologicall... more Because multicellular organisms do not have hydrogenase, H2 has been considered to be biologically inactive in these species, and enterobacteria to be largely responsible for the oxidation of H2 taken into the body. However, we showed previously that inhalation of H2 markedly suppresses brain injury induced by focal ischemia-reperfusion by buffering oxidative stress. Although the reaction constant of H2 with hydroxyl radical in aqueous solution is two to three orders of magnitude lower than that of conventional antioxidants, we showed that hydroxyl radical generated by the Fenton reaction reacts with H2 at room temperature without a catalyst. Suppression of hydroxyl radical by H2 has been applied in ophthalmic surgery. However, many of the anti- inflammatory and other therapeutic effects of H2 cannot be completely explained by its ability to scavenge reactive oxygen species. H2 administration is protective in several disease models, and preculture in the presence of H2 suppresses ox...
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