Crocetin is an aglycon of carotenoid extracted by saffron stigmas (Crocus sativus L.) and known to have a potent anti-oxidative effect. Amyliod β (Aβ), hallmark of Alzheimer’s disease, is reported to have neurotoxi...Crocetin is an aglycon of carotenoid extracted by saffron stigmas (Crocus sativus L.) and known to have a potent anti-oxidative effect. Amyliod β (Aβ), hallmark of Alzheimer’s disease, is reported to have neurotoxicity partly via oxidative stress. In this study, we investigated the effect of crocetin on hippocampal HT22 cell death induced by Aβ1-42. Furthermore, to clarify the mechanism underlying the protective effects of crocetin against Aβ1-42- induced cell death, we measured reactive oxygen species (ROS) production by CM-H2DCFDA kit assay. Crocetin at 1 -10 μM protected HT22 cells against Aβ1-42-induced neuronal cell death and decreased ROS production increased by Aβ1-42. These results that crocetin has the potent neuroprotective effect against Aβ1-42-induced cytotoxicity in hippocampal cells by attenuating oxidative stress, suggest that crocetin may provide a useful therapeutic strategy against Aβ-related disorders.展开更多
Diacylglycerol kinase (DGK) is an enzyme that converts diacylglycerol to phosphatidic acid. Several DGK isoforms have been implicated in the pathogenesis of seizure, but the role of DGKβ in seizure is unknown. In the...Diacylglycerol kinase (DGK) is an enzyme that converts diacylglycerol to phosphatidic acid. Several DGK isoforms have been implicated in the pathogenesis of seizure, but the role of DGKβ in seizure is unknown. In the present study, we investigated the involvement of DGKβ in seizure using DGKβ knockout (KO) mice. Seizures were more severe in DGKβ KO mice than in wild-type (WT) mice after pentylenetetrazol (PTZ) treatment and after kainic acid treatment, but there were no differences in latency to seizure. The expression levels of DGKβ in the hippocampal CA1, CA3, or DG areas did not differ between PTZ (60 mg/kg) treatment and saline treatment. There were fewer parvalbumin-positive interneurons in the hippocampal CA3 area in DGKβ KO mice than in control WT mice, which might partly account for the increased seizure susceptibility displayed by DGKβ KO mice. These results suggest that DGKβ may play a pivotal role in the development of the relevant interneurons, and that on inherent deficiency of DGKβ increases the animal’s sensitivity to seizure-inducing stimuli.展开更多
In the present study, we investigated whether blue light emission diode (LED) light exposure affects the maternal behavior of mice. The brain function of the offspring mice, including short-term memory, locomotor acti...In the present study, we investigated whether blue light emission diode (LED) light exposure affects the maternal behavior of mice. The brain function of the offspring mice, including short-term memory, locomotor activity, anxiety-like behavior, and depression-like behavior, was evaluated. Pregnant mice at day 11 were housed in the apparatus for exposure to blue LED light during the daytime. Nesting behavior and the survival of pups were observed until weaning. After weaning, the offspring mice were bred in normal light conditions until 12 weeks old, and then the Y-maze test, open field test, and tail suspension test were performed. Retinal functions were evaluated by electroretinogram and histological analysis. Blue LED light exposure during the daytime induced retinal damage, but did not affect behavior related to maternal care in maternal mice. In the offspring mice, blue LED light exposure during the daytime did not affect the retina or brain functions. These findings suggest that blue LED light during the daytime might not be a risk factor for disruption of the mother-infant relationship or offspring brain development in mice.展开更多
Glaucoma is a common neurodegenerative disease that can cause blindness and occurs worldwide. Currently, lowering intraocular pressure is the only therapy available to protect retinal ganglion cells (RGCs). However, t...Glaucoma is a common neurodegenerative disease that can cause blindness and occurs worldwide. Currently, lowering intraocular pressure is the only therapy available to protect retinal ganglion cells (RGCs). However, this therapy does not prevent RGC death in all patients. Therefore, new therapeutic approaches for glaucoma are urgently required, and neuroprotection of RGCs is a focus for many researchers. Optineurin (OPTN) is one of the normal tension glaucoma (NTG) relative genes, while mutant OPTN can form a characteristic aggregation, causing RGC death. Hence, elucidation of the mechanism of OPTN aggregation might provide a clue to help understand RGC death. To examine whether non-mutant OPTN could also aggregate, we pharmacologically induced some glaucoma-related stresses, such as endoplasmic reticulum (ER) stress, glutamate toxicity, activation of TNF-α signaling, mitochondrial dysfunction, and autophagic flux impairment. Our results showed that ER stress, TNF-α signaling, and autophagic flux are involved in OPTN aggregation. Furthermore, our data indicated that increased ER stress, activation of TNF-α signaling, and impaired autophagic flux induce OPTN aggregation, suggesting that OPTN aggregation might be an important therapeutic target not only for familial NTG with mutated OPTN but also for patients with glaucoma more generally.展开更多
Depression is a significant public health concern but its pathology remains unclear. Previously, increases in an endoplasmic reticulum (ER) stress-related protein were reported in the temporal cortex of subjects with ...Depression is a significant public health concern but its pathology remains unclear. Previously, increases in an endoplasmic reticulum (ER) stress-related protein were reported in the temporal cortex of subjects with major depressive disorder who had died by suicide. This finding suggests an association between depression and ER stress. The present study was designed to investigate whether acute stress could affect the ER stress response. Mice were immobilized for a period of 6 hr and then expression of ER stress response-related genes was measured by real-time PCR. We also used enzyme-linked immunosorbent assay for concomitant measurement of the plasma corticosterone levels in the mice. The effect of corticosterone on ER stress proteins was further investigated by treating mice with corticosterone for 2 weeks and then measuring ER protein expression by Western blotting. After a 6 hr restraint stress, mRNA levels of ER stress-related genes, such as the 78-kilodalton glucose regulated protein (GRP78), the 94-kilodalton glucose regulated protein (GRP94), and calreticulin, were increased in the cortex, hippocampus, and striatum of mouse brain. Blood plasma corticosterone level was also increased. In the corticosterone-treated mouse model, the expression of GRP78 and GRP94 was significantly increased in the hippocampus. These results suggest that acute stress may affect ER function and that ER stress may be involved in the pathogenesis of restraint stress, including the development of depression.展开更多
Background: This study investigated the safety (cytotoxicity in vitro) and pharmacological effects (ocular hypotensive effects and aqueous humor concentrations in normotensive monkeys in vivo) of latanoprost formulati...Background: This study investigated the safety (cytotoxicity in vitro) and pharmacological effects (ocular hypotensive effects and aqueous humor concentrations in normotensive monkeys in vivo) of latanoprost formulations with benzalkonium chloride (latanoprost with BAK) and without BAK (NP). Methods: A bioequivalence study of latanoprost with BAK and NP was also conducted on human healthy volunteers. Cytotoxicity and the protective effect against H2O2 stress in vitro were evaluated using human corneal epithelial cells. The ocular hypotensive effects in normotensive monkeys were measured by pneumatonometer and the aqueous humor concentrations of latanoprost free acid were determined by liquid chromatography/mass spectrum (LC/MS) methods. The bioequivalence study of latanoprost with BAK and NP was carried out as a single eye drop, two-sequence, crossover randomized study. Results: Cytotoxicity tests in vitro revealed that NP was less toxic than latanoprost with BAK and significantly inhibited H2O2 induced cell damage while latanoprost with BAK did not. The hypotensive efficacy and the latanoprost free acid concentrations in aqueous humor of each formulation were not significantly different in monkeys. In the bioequivalence study, NP was bioequivalent to latanoprost with BAK. NP was safer than latanoprost with BAK with respect the results obtained in the in vitro cytotoxicity test. There was no difference observed between latanoprost with BAK and NP in the IOP lowering effect in monkeys and healthy volunteers. Conclusion: Taken together, these results indicate that NP is as effective as latanoprost with BAK, and is more likely to maintain ocular surface health than latanoprost with BAK.展开更多
Dysphagia induces aspiration and causes aspiration pneumonia. There is no treatment for dysphagia fundamentally. Haloperidol reportedly induces dysphagia. In the present study, we established a haloperidol-induced dys...Dysphagia induces aspiration and causes aspiration pneumonia. There is no treatment for dysphagia fundamentally. Haloperidol reportedly induces dysphagia. In the present study, we established a haloperidol-induced dysphagia model in guinea pigs, and evaluated the effects of ginger, kikyoto, and a mixture of ginger and kikyoto on swallowing. Swallowing ability was evaluated using behavioral tests, computed tomography (CT), and videofluoroscopic examination of swallowing. To investigate the effect of ginger and kikyoto on swallowing, ginger, kikyoto, or a mixture of ginger and kikyoto was administered orally to guinea pigs with haloperidol-induced dysphagia. Effects of these compounds were evaluated with behavioral tests. Chronic administration of haloperidol reduced the number of swallows, as evaluated by the behavioral test and videofluoroscopic examination of swallowing. In our model, these compounds improved swallowing dysfunction. Our results suggest that this model might be useful in revealing the pathogenesis of dysphagia and evaluating compounds that might improve swallowing.展开更多
The expression of cytosolic phospholipase A2 (cPLA2) expression is up-regulated in animal model of ALS and in patients with familial amyotrophic lateral sclerosis (fALS). Inhibition of cyclooxygenase 2 (COX2), which i...The expression of cytosolic phospholipase A2 (cPLA2) expression is up-regulated in animal model of ALS and in patients with familial amyotrophic lateral sclerosis (fALS). Inhibition of cyclooxygenase 2 (COX2), which is a downstream enzyme of cPLA2, ameliorates the impairment of motor function in the ALS model mice. Therefore, the arachidonic acid cascade, including the cPLA2-COX2 pathway, is an important therapeutic target of ALS. The current study was designed to investigate the potential of AK106-001616, an inhibitor of cPLA2, in protection of motor neuron cell death induced by mutant superoxide dismutase (SOD1<sup>G93A</sup>). AK106-001616 (1 - 10 μM) protected NSC34 cells (mouse motor neuron like cells) against SOD1<sup>G93A</sup>-induced motor neuron cell death. Furthermore, aspirin, an inhibitor of COX1/2, reduced the SOD1<sup>G93A</sup>-induced motor neuron cell death at a concentration that inhibited COX2. Celecoxib, a selective COX2 inhibitor, also reduced the SOD1<sup>G93A</sup>-induced motor neuron cell death. These results suggest that the arachidonic acid cascade is important for SOD1<sup>G93A</sup>-induced motor neuron cell death and AK106-001616 has a potent neuroprotective effect against it. AK106-001616 may be a useful therapeutic agent against SOD1<sup>G93A</sup>-induced ALS.展开更多
文摘Crocetin is an aglycon of carotenoid extracted by saffron stigmas (Crocus sativus L.) and known to have a potent anti-oxidative effect. Amyliod β (Aβ), hallmark of Alzheimer’s disease, is reported to have neurotoxicity partly via oxidative stress. In this study, we investigated the effect of crocetin on hippocampal HT22 cell death induced by Aβ1-42. Furthermore, to clarify the mechanism underlying the protective effects of crocetin against Aβ1-42- induced cell death, we measured reactive oxygen species (ROS) production by CM-H2DCFDA kit assay. Crocetin at 1 -10 μM protected HT22 cells against Aβ1-42-induced neuronal cell death and decreased ROS production increased by Aβ1-42. These results that crocetin has the potent neuroprotective effect against Aβ1-42-induced cytotoxicity in hippocampal cells by attenuating oxidative stress, suggest that crocetin may provide a useful therapeutic strategy against Aβ-related disorders.
文摘Diacylglycerol kinase (DGK) is an enzyme that converts diacylglycerol to phosphatidic acid. Several DGK isoforms have been implicated in the pathogenesis of seizure, but the role of DGKβ in seizure is unknown. In the present study, we investigated the involvement of DGKβ in seizure using DGKβ knockout (KO) mice. Seizures were more severe in DGKβ KO mice than in wild-type (WT) mice after pentylenetetrazol (PTZ) treatment and after kainic acid treatment, but there were no differences in latency to seizure. The expression levels of DGKβ in the hippocampal CA1, CA3, or DG areas did not differ between PTZ (60 mg/kg) treatment and saline treatment. There were fewer parvalbumin-positive interneurons in the hippocampal CA3 area in DGKβ KO mice than in control WT mice, which might partly account for the increased seizure susceptibility displayed by DGKβ KO mice. These results suggest that DGKβ may play a pivotal role in the development of the relevant interneurons, and that on inherent deficiency of DGKβ increases the animal’s sensitivity to seizure-inducing stimuli.
文摘In the present study, we investigated whether blue light emission diode (LED) light exposure affects the maternal behavior of mice. The brain function of the offspring mice, including short-term memory, locomotor activity, anxiety-like behavior, and depression-like behavior, was evaluated. Pregnant mice at day 11 were housed in the apparatus for exposure to blue LED light during the daytime. Nesting behavior and the survival of pups were observed until weaning. After weaning, the offspring mice were bred in normal light conditions until 12 weeks old, and then the Y-maze test, open field test, and tail suspension test were performed. Retinal functions were evaluated by electroretinogram and histological analysis. Blue LED light exposure during the daytime induced retinal damage, but did not affect behavior related to maternal care in maternal mice. In the offspring mice, blue LED light exposure during the daytime did not affect the retina or brain functions. These findings suggest that blue LED light during the daytime might not be a risk factor for disruption of the mother-infant relationship or offspring brain development in mice.
文摘Glaucoma is a common neurodegenerative disease that can cause blindness and occurs worldwide. Currently, lowering intraocular pressure is the only therapy available to protect retinal ganglion cells (RGCs). However, this therapy does not prevent RGC death in all patients. Therefore, new therapeutic approaches for glaucoma are urgently required, and neuroprotection of RGCs is a focus for many researchers. Optineurin (OPTN) is one of the normal tension glaucoma (NTG) relative genes, while mutant OPTN can form a characteristic aggregation, causing RGC death. Hence, elucidation of the mechanism of OPTN aggregation might provide a clue to help understand RGC death. To examine whether non-mutant OPTN could also aggregate, we pharmacologically induced some glaucoma-related stresses, such as endoplasmic reticulum (ER) stress, glutamate toxicity, activation of TNF-α signaling, mitochondrial dysfunction, and autophagic flux impairment. Our results showed that ER stress, TNF-α signaling, and autophagic flux are involved in OPTN aggregation. Furthermore, our data indicated that increased ER stress, activation of TNF-α signaling, and impaired autophagic flux induce OPTN aggregation, suggesting that OPTN aggregation might be an important therapeutic target not only for familial NTG with mutated OPTN but also for patients with glaucoma more generally.
文摘Depression is a significant public health concern but its pathology remains unclear. Previously, increases in an endoplasmic reticulum (ER) stress-related protein were reported in the temporal cortex of subjects with major depressive disorder who had died by suicide. This finding suggests an association between depression and ER stress. The present study was designed to investigate whether acute stress could affect the ER stress response. Mice were immobilized for a period of 6 hr and then expression of ER stress response-related genes was measured by real-time PCR. We also used enzyme-linked immunosorbent assay for concomitant measurement of the plasma corticosterone levels in the mice. The effect of corticosterone on ER stress proteins was further investigated by treating mice with corticosterone for 2 weeks and then measuring ER protein expression by Western blotting. After a 6 hr restraint stress, mRNA levels of ER stress-related genes, such as the 78-kilodalton glucose regulated protein (GRP78), the 94-kilodalton glucose regulated protein (GRP94), and calreticulin, were increased in the cortex, hippocampus, and striatum of mouse brain. Blood plasma corticosterone level was also increased. In the corticosterone-treated mouse model, the expression of GRP78 and GRP94 was significantly increased in the hippocampus. These results suggest that acute stress may affect ER function and that ER stress may be involved in the pathogenesis of restraint stress, including the development of depression.
文摘Background: This study investigated the safety (cytotoxicity in vitro) and pharmacological effects (ocular hypotensive effects and aqueous humor concentrations in normotensive monkeys in vivo) of latanoprost formulations with benzalkonium chloride (latanoprost with BAK) and without BAK (NP). Methods: A bioequivalence study of latanoprost with BAK and NP was also conducted on human healthy volunteers. Cytotoxicity and the protective effect against H2O2 stress in vitro were evaluated using human corneal epithelial cells. The ocular hypotensive effects in normotensive monkeys were measured by pneumatonometer and the aqueous humor concentrations of latanoprost free acid were determined by liquid chromatography/mass spectrum (LC/MS) methods. The bioequivalence study of latanoprost with BAK and NP was carried out as a single eye drop, two-sequence, crossover randomized study. Results: Cytotoxicity tests in vitro revealed that NP was less toxic than latanoprost with BAK and significantly inhibited H2O2 induced cell damage while latanoprost with BAK did not. The hypotensive efficacy and the latanoprost free acid concentrations in aqueous humor of each formulation were not significantly different in monkeys. In the bioequivalence study, NP was bioequivalent to latanoprost with BAK. NP was safer than latanoprost with BAK with respect the results obtained in the in vitro cytotoxicity test. There was no difference observed between latanoprost with BAK and NP in the IOP lowering effect in monkeys and healthy volunteers. Conclusion: Taken together, these results indicate that NP is as effective as latanoprost with BAK, and is more likely to maintain ocular surface health than latanoprost with BAK.
文摘Dysphagia induces aspiration and causes aspiration pneumonia. There is no treatment for dysphagia fundamentally. Haloperidol reportedly induces dysphagia. In the present study, we established a haloperidol-induced dysphagia model in guinea pigs, and evaluated the effects of ginger, kikyoto, and a mixture of ginger and kikyoto on swallowing. Swallowing ability was evaluated using behavioral tests, computed tomography (CT), and videofluoroscopic examination of swallowing. To investigate the effect of ginger and kikyoto on swallowing, ginger, kikyoto, or a mixture of ginger and kikyoto was administered orally to guinea pigs with haloperidol-induced dysphagia. Effects of these compounds were evaluated with behavioral tests. Chronic administration of haloperidol reduced the number of swallows, as evaluated by the behavioral test and videofluoroscopic examination of swallowing. In our model, these compounds improved swallowing dysfunction. Our results suggest that this model might be useful in revealing the pathogenesis of dysphagia and evaluating compounds that might improve swallowing.
文摘The expression of cytosolic phospholipase A2 (cPLA2) expression is up-regulated in animal model of ALS and in patients with familial amyotrophic lateral sclerosis (fALS). Inhibition of cyclooxygenase 2 (COX2), which is a downstream enzyme of cPLA2, ameliorates the impairment of motor function in the ALS model mice. Therefore, the arachidonic acid cascade, including the cPLA2-COX2 pathway, is an important therapeutic target of ALS. The current study was designed to investigate the potential of AK106-001616, an inhibitor of cPLA2, in protection of motor neuron cell death induced by mutant superoxide dismutase (SOD1<sup>G93A</sup>). AK106-001616 (1 - 10 μM) protected NSC34 cells (mouse motor neuron like cells) against SOD1<sup>G93A</sup>-induced motor neuron cell death. Furthermore, aspirin, an inhibitor of COX1/2, reduced the SOD1<sup>G93A</sup>-induced motor neuron cell death at a concentration that inhibited COX2. Celecoxib, a selective COX2 inhibitor, also reduced the SOD1<sup>G93A</sup>-induced motor neuron cell death. These results suggest that the arachidonic acid cascade is important for SOD1<sup>G93A</sup>-induced motor neuron cell death and AK106-001616 has a potent neuroprotective effect against it. AK106-001616 may be a useful therapeutic agent against SOD1<sup>G93A</sup>-induced ALS.
