Intestinal microbiota may play a significant role in the development and progression of mild cognitive impairment (MCI). In addition, sex differences in the prevalence of MCI and intestinal microbiota are likely to exist. Therefore, this study investigated the association between MCI and intestinal microbiota by comparing Japanese patients in their 70s with MCI (11 males and 18 females) and disease-free controls (17 males and 23 females), taking sex into account.
View Article and Find Full Text PDFAims: Chronic inflammation plays crucial roles in obesity-induced metabolic diseases. Protein tyrosine phosphatase receptor type O (PTPRO) is a member of the R3 subfamily of receptor-like protein tyrosine phosphatases. We previously suggested a role for PTPRO in the inactivation of the insulin receptor.
View Article and Find Full Text PDFCompelling evidence support an involvement of oxidative stress and intestinal inflammation as early events in the predisposition and development of obesity and its related comorbidities. Here, we show that deficiency of the major mitochondrial antioxidant enzyme superoxide dismutase 2 (SOD2) in the gastrointestinal tract drives spontaneous obesity. Intestinal epithelium-specific ablation in mice induced adiposity and inflammation via phospholipase A2 (PLA2) activation and increased release of omega-6 polyunsaturated fatty acid arachidonic acid.
View Article and Find Full Text PDFThe oxygen consumption rate (OCR) and cytochrome c oxidase (CcO) activity of respiratory complex IV (CIV) in brain mitochondria significantly decline in middle-aged male mice compared to younger male mice. To explore the mechanisms underlying the regulation of brain mitochondrial function, we examined CIV-associated proteins, and identified actin inside the isolated brain mitochondria. Inhibiting actin polymerization using cytochalasin B (CB) significantly enhanced the OCR and CcO activity of CIV in the mitochondria.
View Article and Find Full Text PDFEph receptors play pivotal roles in the axon guidance of retinal ganglion cells (RGCs) at the optic chiasm and the establishment of the topographic retinocollicular map. We previously demonstrated that protein tyrosine phosphatase receptor type O (PTPRO) is specifically involved in the control of retinotectal projections in chicks through the dephosphorylation of EphA and EphB receptors. We subsequently revealed that all the mouse R3 subfamily members (PTPRB, PTPRH, PTPRJ, and PTPRO) of the receptor protein tyrosine phosphatase (RPTP) family inhibited Eph receptors as their substrates in cultured mammalian cells.
View Article and Find Full Text PDFThe oxygen consumption rate (OCR) in brain mitochondria is significantly lower in aged mice than in young mice, and the reduced OCR is rescued by administration of water-solubilized CoQ to aged mice via drinking water. However, the mechanism behind this remains unclear. Here, we show that the activity of respiratory complex IV (CIV) in brain mitochondria declined in aged mice than in young mice, with no significant change in individual respiratory complex levels and their supercomplex assembly.
View Article and Find Full Text PDFThe aim of this study was to investigate the effect of N-acetyl glucosamine and proteoglycan-containing supplement (NGPS) on knee pain and locomotor functions in middle-aged and elderly persons with knee pain. An open trial was conducted on 19 subjects suffering from knee pain. The subjects, aged (55.
View Article and Find Full Text PDFBrain mitochondrial function declines with age; however, the accompanying behavioral and histological alterations that are characteristic of Parkinson's disease (PD) are poorly understood. We found that the mitochondrial oxygen consumption rate (OCR) and coenzyme Q (CoQ) content were reduced in aged (15-month-old) male mice compared to those in young (6-month-old) male mice. Concomitantly, motor functions, including the rate of movement and exploratory and voluntary motor activities, were significantly reduced in the aged mice compared to the young mice.
View Article and Find Full Text PDFPurpose: A healthy conjunctiva secreting mucins is essential for maintaining the integrity of the ocular surface epithelium. We used Cu, Zn-superoxide dismutase 1-deficient mice (Sod1-/- mice) and investigated the effect of oxidative stress on the tear function, conjunctival phenotype, and ocular surface mucin expression.
Methods: Fifty-week-old C57/B6 wild-type (WT) and Sod1-/- mice were used for evaluations of the tear film breakup time and periodic acid Schiff staining of the conjunctival specimens to detect goblet cell densities in the conjunctiva.
High-fat diet (HFD) triggers insulin resistance and diabetes mellitus, but their link remains unclear. Characterization of overt hyperglycemia in insulin receptor mutant (Insr(P1195L/+)) mice exposed to HFD (Insr(P1195L/+)/HFD mice) revealed increased glucose-6-phosphatase (G6pc) expression in liver and increased gluconeogenesis from glycerol. Lipolysis in white adipose tissues (WAT) and lipolysis-induced blood glucose rise were increased in Insr(P1195L/+)/HFD mice, while wild-type WAT transplantation ameliorated the hyperglycemia and the increased G6pc expression.
View Article and Find Full Text PDFPurpose. This study evaluated the effects of using a newly developed eye cleansing formulation (Eye Shampoo) to cleanse the eyelids for 4 weeks in a parallel-group comparative study in women with chronic eye discomfort caused by heavy use of eye makeup and poor eye hygiene habits. Methods.
View Article and Find Full Text PDFOxidative stress is believed to greatly contribute to the pathogenesis of various diseases, including neurodegeneration. Impairment of mitochondrial energy production and increased mitochondrial oxidative damage are considered early pathological events that lead to neurodegeneration. Manganese superoxide dismutase (Mn-SOD, SOD2) is a mitochondrial antioxidant enzyme that converts toxic superoxide to hydrogen peroxide.
View Article and Find Full Text PDFMechanical stress and aging are major risk factors of cartilage degeneration. Human studies have previously reported that oxidative damage increased, while SOD2 protein was reciprocally downregulated in osteoarthritic degenerated cartilage. However, it remains unclear whether mitochondrial superoxide imbalance in chondrocytes causes cartilage degeneration.
View Article and Find Full Text PDFOsteocytes are major bone cells that play a crucial role in maintaining the quality of and healing damage to bone tissue. The number of living osteocytes and canalicular networks declines in an age-dependent manner. However, the pathological effects of mitochondrial redox imbalances on osteocytes and bone metabolism have not been fully elucidated.
View Article and Find Full Text PDFWe investigated age-induced changes in mRNA expression profiles of sex-steroidogenic enzymes and sex-steroid receptors in 3-, 12-, and 24-month-old male rat brain subregions [cerebral cortex (CC), hypothalamus (Hy) and cerebellum (CL)]. In many cases, the expression levels of mRNA decreased with age for androgen synthesis enzyme systems, including Cyp17a1, Hsd17b and Srd5a in the CC and CL, but not in the Hy. Estradiol synthase Cyp19a1 did not show age-induced decline in the Hy, and nearly no expression of Cyp19a1 was observed in the CC and CL over 3-24 m.
View Article and Find Full Text PDFMutational inactivation of clk-1, which encodes an enzyme necessary for the biosynthesis of coenzyme Q (CoQ), extends the lifespan of Caenorhabditis elegans. However, whether mammalian clk-1 regulates the lifespan of mice is not known because clk-1-deficiencies are embryonic lethal. Here, we investigated the lifespan of clk-1 transgenic mice (Tg96/I), which were rescued from embryonic lethality via the transgenic expression of mouse clk-1.
View Article and Find Full Text PDFPurpose: To investigate the role of a water and mucin secretagogue (3% diquafosol sodium eye drops) on the tear function and conjunctival ocular surface changes in Sod1(-/-) in comparison to the wild-type (WT) mice.
Methods: Fourteen eyes of 7 Sod1(-/-) male mice with C57BL/background and 14 eyes of 7 C57BL6 strain wild-type male mice were examined at 40 weeks in this study. All mice had application of 3% diquafosol ophthalmic solution six times a day for 2 weeks.
Cardiac electrophysiological alterations induced by chronic exposure to reactive oxygen species and protective effects of dietary antioxidant have not been thoroughly examined. We recorded surface electrocardiograms (ECG) and evaluated cellular electrophysiological abnormalities in enzymatically-dissociated left ventricular (LV) myocytes in heart/muscle-specific manganese-superoxide dismutase-deficient (H/M-Sod2(-/-)) mice, which exhibit dilated cardiomyopathy due to increased oxidative stress. We also investigated the influences of intake of apple polyphenols (AP) containing mainly procyanidins with potent antioxidant activity.
View Article and Find Full Text PDFMelinjo (Gnetum gnemon L.) seed extract (MSE) containing trans-resveratrol (3,5,4'-trihydroxy-trans-stilbene) and other derivatives exerts various beneficial effects. However, its mechanism of action in humans remains unknown.
View Article and Find Full Text PDFPurpose: To investigate the efficacy of 2% rebamipide ophthalmic solution on the tear functions and ocular surface status of the superoxide dismutase-1(Sod1(-/-)) mice.
Methods: Two percent Rebamipide ophthalmic solution was applied to 40-week-old male Sod1(-/-) and wild-type (WT) mice four times a day for 2 weeks. We examined the cytokine concentrations in the tear fluid (by CytoBead assay), tear film break-up time, amount of tear production, and expressions of mucins 1, 4, and 5AC, by RT-PCR.
Gnetum gnemon is an arboreal dioecious plant that is cultivated in Indonesia. The seeds of this species mainly contain dimeric stilbenoid compounds [gnetin C (1), gnemonoside A (2), and gnemonoside D (3)] along with trans-resveratrol (4). trans-Resveratrol has been reported to have antiaging, anticancer, and antidiabetic effects, as well as being a calorie restriction mimetic.
View Article and Find Full Text PDFRespir Physiol Neurobiol
June 2013
The working hypothesis of this study was that chronically increased tissue oxygenation would facilitate respiratory endurance to chemical stimuli. We investigated the ventilatory responses to hypoxia and hypercapnia before and after carotid chemodenervation in the anesthetized, spontaneously breathing Presbyterian, which carry a low affinity variant of hemoglobin, and in wild-type mice. We found a dampening of all chemosensory responses in Presbyterian hemoglobinopathy.
View Article and Find Full Text PDFRedox imbalance elevates the reactive oxygen species (ROS) level in cells and promotes age-related diseases. Superoxide dismutases (SODs) are antioxidative enzymes that catalyze the degradation of ROS. There are three SOD isoforms: SOD1/CuZn-SOD, SOD2/Mn-SOD, and SOD3/EC-SOD.
View Article and Find Full Text PDFIn this study we tried to confirm the effect of an astaxanthin-rich Haematococcus pluvialis extract on cognitive function in 96 subjects by a randomised double-blind placebo-controlled study. Healthy middle-aged and elderly subjects who complained of age-related forgetfulness were recruited. Ninety-six subjects were selected from the initial screen, and ingested a capsule containing astaxanthin-rich Haematococcus pluvialis extract, or a placebo capsule for 12 weeks.
View Article and Find Full Text PDFOxidative stress is involved in the pathogenesis of neurodegeneration. Amyloid β (Aβ) oligomer as an intermediate of aggregates causes memory loss in Alzheimer's disease (AD). We have suggested that oxidative stress plays an important role in Aβ oligomerization and cognitive impairment using a human amyloid precursor protein (hAPP) transgenic AD mice lacking cytoplasmic superoxide dismutase (hAPP/Sod1-/-).
View Article and Find Full Text PDF