Targeting autophagy to discover the Piper wallichii petroleum ether fraction exhibiting antiaging and anti-Alzheimer's disease effects in Caenorhabditis elegans.

BACKGROUND: With population aging, the incidence of aging-related Alzheimer's disease (AD) is increasing, accompanied by decreased autophagy activity. At present, Caenorhabditis elegans (C. elegans) is widely employed to evaluate autophagy and in research on aging and aging-related diseases in vivo. To discover autophagy activators from natural medicines and investigate their therapeutic potential in antiaging and anti-AD effects, multiple C. elegans models related to autophagy, aging, and AD were used. METHOD: In this study, we employed the DA2123 and BC12921 strains to discover potential autophagy inducers using a self-established natural medicine library. The antiaging effect was evaluated by determining the lifespan, motor ability, pumping rate, lipofuscin accumulation of worms, and resistance ability of worms under various stresses. In addition, the anti-AD effect was examined by detecting the paralysis rate, food-sensing behavior, and amyloid-ß and Tau pathology in C. elegans. Moreover, RNAi technology was used to knock down the genes related to autophagy induction. RESULTS: We discovered that Piper wallichii extract (PE) and the petroleum ether fraction (PPF) activated autophagy in C. elegans, as evidenced by increased GFP-tagged LGG-1 foci and decreased GFP-p62 expression. In addition, PPF extended the lifespan and enhanced the healthspan of worms by increasing body bends and pumping rates, decreasing lipofuscin accumulation, and increasing resistance to oxidative, heat, and pathogenic stress. Moreover, PPF exhibited an anti-AD effect by decreasing the paralysis rate, improving the pumping rate and slowing rate, and alleviating Aß and Tau pathology in AD worms. However, the feeding of RNAi bacteria targeting unc-51, bec-1, lgg-1, and vps-34 abolished the antiaging and anti-AD effects of PPF. CONCLUSION: Piper wallichii may be a promising drug for antiaging and anti-AD. More future studies are also needed to identify autophagy inducers in Piper wallichii and clarify their molecular mechanisms.

Longevity-promoting properties of ginger extract in Caenorhabditis elegans via the insulin/IGF-1 signaling pathway.

Ginger is a traditional medicinal and edible plant with multiple health-promoting properties. Nevertheless, the effects and potential mechanism of ginger on antiaging remain unknown. The aim of this study was to comprehend the antiaging effects and potential mechanism of ginger in Caenorhabditis elegans (C. elegans). The current findings showed that the lifespan of C. elegans was prolonged by 23.16% with the supplementation of 60 µg mL-1 ginger extract (GE), and the extension of lifespan was mainly attributed to the major bioactive compounds in GE, 6-, 8-, 10-gingerol and 6-, 8-, 10-shogaol. Subsequently, GE promoted healthy aging by improving nematode movement and attenuating lipofuscin accumulation, and enhanced stress tolerance by up-regulating the expression of stress-related genes and activating DAF-16 and SKN-1. Moreover, lifespan assays of relative mutants revealed that GE mediated extension of lifespan via the insulin/IGF-1 signaling (IIS) pathway. In summary, GE endowed nematodes (C. elegans) with longevity and stress resistance in an IIS pathway dependent manner.

Retinal Pigment Epithelium in Human Donor Eyes Contains Higher Levels of Bisretinoids Including A2E in Periphery than Macula.

Purpose: With age, human retinal pigment epithelium (RPE) accumulates bisretinoid fluorophores that may impact cellular function and contribute to age-related macular degeneration (AMD). Bisretinoids are comprised of a central pyridinium, dihydropyridinium, or cyclohexadiene ring. The pyridinium bisretinoid A2E has been extensively studied, and its quantity in the macula has been questioned. Age-changes and distributions of other bisretinoids are not well characterized. We measured levels of three bisretinoids and oxidized A2E in macula and periphery in human donor eyes of different ages. Methods: Eyes (N = 139 donors, 61 women and 78 men, aged 40-80 years) were dissected into 8 mm diameter macular and temporal periphery punches. Using liquid chromatography - electrospray ionization - mass spectrometry (LC-ESI-MS) and an authentic synthesized standard, we quantified A2E (ng). Using LC-ESI-MS and a 50-eye-extract of A2E, we semiquantified A2E and 3 other compounds (eye extract equivalent units [EEEUs): A2-glycerophosphoethanolamine (A2GPE), dihydropyridine phosphatidyl ethanolamine (A2DHPE), and monofuranA2E (MFA2E). Results: A2E quantities in ng and EEEUs were highly correlated (r = 0.97, P < 0.001). From 262 eyes, 5 to 9-fold higher levels were observed in the peripheral retina than in the macula for all assayed compounds. A2E, A2DHPE, and MFA2E increased with age, whereas A2GPE remained unaffected. No significant right-left or male-female differences were detected. Conclusions: Significantly higher levels were observed in the periphery than in the macula for all assayed compounds signifying biologic differences between these regions. Levels of oxidized A2E parallel native A2E and not the distribution of retinal illuminance. Data will assist with the interpretion of clinical trial outcomes of agents targeting bisretinoid-related pathways.

Impacts of engineered iron nanoparticles on oxidative stress, fatty acid composition, and histo-architecture of the smooth scallop Flexopecten glaber.

Engineered iron nanoparticles are widely used in environmental remediation, yet their potential toxic effects on marine biota remain poorly elucidated. This study aimed to gain insight into the nanoscale zero-valent iron (NZVI) toxicity mechanisms for marine invertebrates. Aside from the effect on oxidative status and histopathology, the effect of NZVI on lipid metabolism in bivalves was studied for the first time. To this end, specimens of Flexopecten glaber were exposed to ascending concentrations (0.5, 1, and 1.5 mg/L) of NZVI for 96 h. Results illustrate differential patterns of iron accumulation in the gills and the digestive gland. By increasing NZVI concentrations, the total iron level tended to markedly increase in the gills and decrease in the digestive gland, reaching 132 and 37.6 µg/g DW, respectively, in the specimens exposed to 1.5 mg/L. Biochemical and cellular biomarkers highlighted that NZVI caused oxidative stress (measured as hydrogen peroxide, malondialdehyde, and advanced oxidation protein product levels) and alterations of antioxidant defense systems, including reduced glutathione, non-protein thiol, glutathione peroxidase, superoxide dismutase, and catalase. Modulation of lipid metabolism with changed fatty acid compositions (mainly an increase in the saturation and a decrease in unsaturation levels) was also observed in both gills and digestive gland. Moreover, several histological damages, including lipofuscin accumulation, infiltrative inflammations, and digestive tubule alterations, were observed in the two studied organs, providing supplementary evidence regarding the toxic effect of NZVI. This study adds to the growing body of evidence pointing to the hazardous impacts of iron NPs on aquatic ecosystems.

Citrulline protects human retinal pigment epithelium from hydrogen peroxide and iron/ascorbate induced damages.

Oxidative stress plays an important role in the ageing of the retina and in the pathogenesis of retinal diseases such as age-related macular degeneration (ARMD). Hydrogen peroxide is a reactive oxygen species generated by the photo-excited lipofuscin that accumulates during ageing in the retinal pigment epithelium (RPE), and the age-related accumulation of lipofuscin is associated with ARMD. Iron also accumulates with age in the RPE that may contribute to ARMD as an important source of oxidative stress. The aim of this work was to investigate the effects of L-Citrulline (CIT), a naturally occurring amino acid with known antioxidant properties, on oxidative stressed cultured RPE cells. Human RPE (ARPE-19) cells were exposed to hydrogen peroxide (H2 O2 ) or iron/ascorbate (I/A) for 4 h, either in the presence of CIT or after 24 h of pretreatment. Here, we show that supplementation with CIT protects ARPE-19 cells against H2 O2 and I/A. CIT improves cell metabolic activity, decreases ROS production, limits lipid peroxidation, reduces cell death and attenuates IL-8 secretion. Our study evidences that CIT is able to protect human RPE cells from oxidative damage and suggests potential protective effect for the treatment of retinal diseases associated with oxidative stress.

Modulation of autophagy by an innovative phytocosmetic preparation (Myrothamnus flabelifolia and Coffea arabica) in human fibroblasts and its effects in a clinical randomized placebo-controlled trial.

BACKGROUND: Autophagy is a natural and evolutionary mechanism that reduces cell toxic components and reutilizes metabolites to provide energy and renew cell function, which is linked to a wide range of age-related diseases, including those that affect the skin. Positive modulation of autophagy is useful to treat skin disorders and new active herbal products are potential candidates as autophagy modulators. AIMS: The present study aimed to evaluate the effects of a phytocosmetic formulation containing Myrothamnus flabellifolia leaf and Coffea arabica seed plant extracts (MflCas) on the ubiquitin-proteasome and autophagy markers in human dermal fibroblasts, and investigate its topical skin effects in a randomized, simple-blind, and placebo-controlled trial. METHODS: Human dermal fibroblasts were used to determine proteasome activity, protein carbonylation, LC3B protein, and lipofuscin production by luminescence and immune-enzymatic assays, and to determinate gene expression of autophagy biomarkers (Atg5, Atg7, EI24, EIF2A, Park2, foxo1, and mTOR) by RT-PCR. A clinical trial was conducted to evaluate the effects of MflCas on the hand, face, and forearms skin features after treatment by 56 days. RESULTS: Topical treatment with MflCas improved several skin features of volunteers, mainly skin aging and pigmentation signals. On the hand skin, MflCas 2% after 56 days of treatment, reduced the spots length (30.8%), skin contrast (42.2%), and increased skin homogeneity (63.2%) and skin lightening effect (1.4%). On the face skin, topical treatment after 56 days reduced the spots length (21.5%), wrinkles area (8.1%), and wrinkles volume (5.6%) with an increment in face skin homogeneity (59.5%). These effects were related to the ability of MflCas to reduce proteasome activity protein carbonylation, and lipofuscin level, increase LC3B production, downregulate Atg7 and mTOR genes, and upregulate Park2 gene expressions. CONCLUSIONS: The phytocosmetic preparation containing Myrothamnus flabellifolia leaf and Coffea arabica seed modulated ubiquitin-proteasome and autophagy process, representing an innovative and safe herbal preparation to improve skin features, mainly acting as skin anti-aging and lightening agent.

Tissue-Specific Gamma-Flicker Light Noninvasively Ameliorates Retinal Aging.

Aging is a risk factor for multiple retinal degeneration diseases. Entraining brain gamma oscillations with gamma-flicker light (γFL) has been confirmed to coordinate pathological changes in several Alzheimer's disease mouse models and aged mice. However, the direct effect of γFL on retinal aging remains unknown. We assessed retinal senescence-associated beta-galactosidase (ß-gal) and autofluorescence in 20-month-old mice and found reduced ß-gal-positive cells in the inner retina and diminished lipofuscin accumulation around retinal vessels after 6 days of γFL. In immunofluorescence, γFL was further demonstrated to ameliorate aging-related retinal changes, including a decline in microtubule-associated protein 1 light chain 3 beta expression, an increase in complement C3 activity, and an imbalance between the anti-oxidant factor catalase and pro-oxidant factor carboxymethyl lysine. Moreover, we found that γFL can increase the expression of activating transcription factor 4 (ATF4) in the inner retina, while revealing a decrease of ATF4 expression in the inner retina and positive expression in the outer segment of photoreceptor and RPE layer for aged mice. Western blotting was then used to confirm the immunofluorescence results. After mRNA sequencing (NCBI Sequence Read Archive database: PRJNA748184), we found several main mechanistic clues, including mitochondrial function and chaperone-mediated protein folding. Furthermore, we extended γFL to aged Apoe-/- mice and showed that 1-m γFL treatment even improved the structures of retinal-pigment-epithelium basal infolding and Bruch's membrane. Overall, γFL can orchestrate various pathological characteristics of retinal aging in mice and might be a noninvasive, convenient, and tissue-specific therapeutic strategy for retinal aging.

Grifola frondosa (Maitake) Extract Reduces Fat Accumulation and Improves Health Span in C. elegans through the DAF-16/FOXO and SKN-1/NRF2 Signalling Pathways.

In recent years, food ingredients rich in bioactive compounds have emerged as candidates to prevent excess adiposity and other metabolic complications characteristic of obesity, such as low-grade inflammation and oxidative status. Among them, fungi have gained popularity for their high polysaccharide content and other bioactive components with beneficial activities. Here, we use the C. elegans model to investigate the potential activities of a Grifola frondosa extract (GE), together with the underlying mechanisms of action. Our study revealed that GE represents an important source of polysaccharides and phenolic compounds with in vitro antioxidant activity. Treatment with our GE extract, which was found to be nongenotoxic through a SOS/umu test, significantly reduced the fat content of C. elegans, decreased the production of intracellular ROS and aging-lipofuscin pigment, and increased the lifespan of nematodes. Gene expression and mutant analyses demonstrated that the in vivo anti-obesity and antioxidant activities of GE were mediated through the daf-2/daf-16 and skn-1/nrf-2 signalling pathways, respectively. Taken together, our results suggest that our GE extract could be considered a potential functional ingredient for the prevention of obesity-related disturbances.

Pharmacologic activation of autophagy without direct mTOR inhibition as a therapeutic strategy for treating dry macular degeneration.

Dry age-related macular degeneration (AMD) is marked by the accumulation of extracellular and intracellular lipid-rich deposits within and around the retinal pigment epithelium (RPE). Inducing autophagy, a conserved, intracellular degradative pathway, is a potential treatment strategy to prevent disease by clearing these deposits. However, mTOR inhibition, the major mechanism for inducing autophagy, disrupts core RPE functions. Here, we screened autophagy inducers that do not directly inhibit mTOR for their potential as an AMD therapeutic in primary human RPE culture. Only two out of more than thirty autophagy inducers tested reliably increased autophagy flux in RPE, emphasizing that autophagy induction mechanistically differs across distinct tissues. In contrast to mTOR inhibitors, these compounds preserved RPE health, and one inducer, the FDA-approved compound flubendazole (FLBZ), reduced the secretion of apolipoprotein that contributes to extracellular deposits termed drusen. Simultaneously, FLBZ increased production of the lipid-degradation product ß-hydroxybutyrate, which is used by photoreceptor cells as an energy source. FLBZ also reduced the accumulation of intracellular deposits, termed lipofuscin, and alleviated lipofuscin-induced cellular senescence and tight-junction disruption. FLBZ triggered compaction of lipofuscin-like granules into a potentially less toxic form. Thus, induction of RPE autophagy without direct mTOR inhibition is a promising therapeutic approach for dry AMD.

Material basis, effect, and mechanism of ethanol extract of Pinellia ternata tubers on oxidative stress-induced cell senescence.

BACKGROUND: The tuber of Pinellia ternata has been used for a thousand years in China. P. ternata possessed the activities of anti-emetic, sedative-hypnotic, anti-cancer, anti-asthmatic, anti-tussive, and anti-inflammatory. It is the representative of expectorant medicines in Traditional Chinese Medicine (TCM). Phlegm is the pathological product and a new pathogenic factor of the metabolite, which is analogous to the damage of oxidative stress. PURPOSE: The objectives of the study were to investigate the protective activity and mechanism of ethanol extract of P. ternata tubers (PTE) and its main constituents on oxidative stress-induced cell senescence. METHODS: H2O2 and AAPH were used to establish cellular senescence models. The anti-aging effects of PTE and its components were evaluated by SA-ß-gal staining, flow cytometry, scanning electron microscope (SEM), and multiple microplate reader, the molecular mechanisms of them were investigated by qRT-PCR and Western Blot. RESULTS: We found PTE exhibited the apparent effect on cell senescence, evidenced by inhibiting senescence ß-Galactosidase (SA-ß-gal) expression, lipofuscin accumulation, cell cycle arrest at the G2/M phase, oxidative damage and apoptosis, and increasing telomerase activity. Their mechanisms were related to increase expressions of SIRT1, forkhead box 3a (Foxo3a), Bcl-2, active regulator of SIRT1, RPS19BP1 (AROS), and Hu antigen R (HuR), but decrease Bax, p53 and deleted in breast cancer 1 (DBC1) levels. Furthermore, adenosine, and succinic acid, as the critical substances in PTE, could also inhibit SA-ß-gal expression and cell cycle arrest, down-regulate the expression of Bax, and up-regulate Bcl-2, SirT1, and Foxo3a. CONCLUSIONS: We have demonstrated that PTE slows down oxidative stress-induced cell senescence, and adenosine and succinic acid are the key active components.

Perspectives on using laser fluorescence spectroscopy in chronological skin ageing assessment.

INTRODUCTION: Laser fluorescence spectroscopy (LFS) is a potential tool for diagnosing pathological skin processes such as fibrosis, hypoxia, and inflammation. This article describes the results of the non-invasive assessment of skin autofluorescence for animals of different ages. METHODS: The study was performed on outbred white male mice (n = 14). Fluorescence spectra were measured using the multifunctional device LAKK-M (SPE Lazma, Moscow, Russia), which implements LFS in vivo. The method is to record the fluorescence spectrum of a tissue after laser irradiation at a wavelength of λe excites its fluorescence. The wavelength λe is selected corresponding to specific fluorophore properties. To excite the fluorescence, the wavelength λe = 535 nm was used, which made it possible to estimate the fluorescence intensity of the lipofuscin. RESULTS: Increased autofluorescence of lipofuscin in the green waveband was detected in animals in the older age group compared to the younger group using LFS. It is important to note that the autofluorescence spectra of lipofuscin are in superposition with the spectra of other fluorophores and that the autofluorescence spectra of lipofuscin overlap the spectra of other fluorophores such as porphyrins. This may affect the interpretation of LFS data. CONCLUSIONS: Adjustment of animal age is necessary for the optical assessment of pathological processes using LFS.

Effects of diets high in corn oil or in extra virgin olive oil on oxidative stress in an experimental model of breast cancer.

Experimental evidence highlights the importance of dietetic factors on breast cancer. In this work we aimed to analyze the effects two oils, corn oil (rich in n-6 polyunsaturated fatty acids -PUFA-) and extra virgin olive oil (EVOO), on oxidative stress in an animal model of breast carcinogenesis. Female rats were fed a low-fat control, a high-corn oil, or a high-EVOO diet from weaning or after induction with 7,12-dimethylbenz[a]anthracene at 53 days. Animals were euthanized at 36, 51, 100 and 246 days of age. We analyzed antioxidant enzymes (mRNA and activity of superoxide dismutase, glutathione peroxidase and catalase), non-enzymatic capacity (oxidized and reduced glutathione) and DNA damage (8-oxo-dG) in tumors and mammary gland at different ages. We also analyzed lipid peroxidation (isoprostanes in serum and lipofuscin in liver). Results indicated a decrease in the enzymatic antioxidant capacity and increased oxidative stress in mammary gland of healthy young animals after a short period of high-fat diets intake, followed by an adaptation to chronic dietary intervention. After induction both diets, especially the one high in n-6 PUFA, increased the oxidized glutathione. In tumors no clear effects of the high-fat diets were observed, although in the long-term lipofuscin and 8-oxo-dG suggested greater oxidative damage by effect of the n-6 PUFA-rich diet. Considering the differential effects of these diets on mammary carcinogenesis that we have previously reported, this study suggests that these high-fat diets could have an effect on oxidative stress that would lead to different signaling pathways.

A newly characterized exopolysaccharide from Sanghuangporus sanghuang.

Sanghuangporus sanghuang is a well-known pharmacodynamic and economically important edible fungus associated with mulberry (Morus spp.). A distinctly new exopolysaccharide (EPS), designated SHP-2 was obtained from S. sanghuang P0988 broth, and its structure and anti-aging prosperity were characterized. SHP-2 was found to be composed of a back-bone of →4)-ß-Manp-(1→4)-α-Araf-(1→3,4)-α-Glcp(1→3,4)-α-Glcp-(1→3,4)-α-Glcp-(1→3,4)-α-Glcp-(1→3,4)-α-Glcp-(1→6)-α-Galp-(1→4)-ß-Manp-(1→ and five branches, including four α-D-Glcp-(1→ and one α-D-Manp-(1→SHP-2 was shown to increase antioxidant enzyme activities including catalase (CAT) and superoxide dismutase (SOD) activities, as well as trolox equivalent antioxidant (TEAC) capacity in serum of mice pre-treated with D-Gal, while reducing lipofuscin levels. SHP-2 exerted a favorable influence on immune organ coefficients and ameliorated the histopathological hepatic lesions and apoptosis in hepatocytes of D-galactose-aged mice almost in a dose-dependent manner. Using the same analytical methods, on comparison with previously studied EPS compounds (i.e. SHP-1), SHP-2 was found to have more complex structure, larger molecule weight, and different anti-aging properties. The results presented here suggest that not only does EPS bioactivity vary with respect to molecular structures and molecule weight, but that multiple structures with different activity can be expressed by a single fungal strain. These results may help understanding the anti-aging prosperity of these polysaccharides for use in health foods or dietary supplements.

Pantothenate Rescues Iron Accumulation in Pantothenate Kinase-Associated Neurodegeneration Depending on the Type of Mutation.

Neurodegeneration with brain iron accumulation (NBIA) is a group of inherited neurologic disorders in which iron accumulates in the basal ganglia resulting in progressive dystonia, spasticity, parkinsonism, neuropsychiatric abnormalities, and optic atrophy or retinal degeneration. The most prevalent form of NBIA is pantothenate kinase-associated neurodegeneration (PKAN) associated with mutations in the gene of pantothenate kinase 2 (PANK2), which is essential for coenzyme A (CoA) synthesis. There is no cure for NBIA nor is there a standard course of treatment. In the current work, we describe that fibroblasts derived from patients harbouring PANK2 mutations can reproduce many of the cellular pathological alterations found in the disease, such as intracellular iron and lipofuscin accumulation, increased oxidative stress, and mitochondrial dysfunction. Furthermore, mutant fibroblasts showed a characteristic senescent morphology. Treatment with pantothenate, the PANK2 enzyme substrate, was able to correct all pathological alterations in responder mutant fibroblasts with residual PANK2 enzyme expression. However, pantothenate had no effect on mutant fibroblasts with truncated/incomplete protein expression. The positive effect of pantothenate in particular mutations was also confirmed in induced neurons obtained by direct reprograming of mutant fibroblasts. Our results suggest that pantothenate treatment can stabilize the expression levels of PANK2 in selected mutations. These results encourage us to propose our screening model as a quick and easy way to detect pantothenate-responder patients with PANK2 mutations. The existence of residual enzyme expression in some affected individuals raises the possibility of treatment using high dose of pantothenate.

Yokukansan Ameliorates Hippocampus-Dependent Learning Impairment in Senescence-Accelerated Mouse.

Yokukansan (YKS) is a traditional Japanese herbal medicine. It has been currently applied for treating behavioral and psychological symptoms of dementia in Japan. We investigated the effect of YKS on learning ability, hippocampal cell proliferation, and neural ultrastructural features in senescence-accelerated mouse prone 8 (SAMP8), a proposed animal model of Alzheimer's disease. Five-month-old male SAMP8 mice were randomly assigned to control and experimental groups. The control group had drug-free water ad libitum. The experimental mice were given 0.15% aqueous solution of YKS orally for eight weeks. Learning ability was assessed in Morris water maze test. Hippocampal cell proliferation was investigated using bromodeoxyuridine immunohistochemical method. The neural ultrastructural features, including myelin sheath and synapse, were investigated electron microscopy. Administration with YKS improved the hippocampal cell proliferation in dentate gyrus, and ameliorated learning impairment in SAMP8 mice. Numerous lipofuscin inclusions were presented in hippocampal neurons of the control mice. However, little were found after treatment with YKS. Myelin sheath was thicker and postsynaptic density length was longer after treatment with YKS. Administration with YKS ameliorated learning impairment in SAMP8 mice, mediated at least partially via delaying neuronal aging process, neurogenesis, myelin sheath and synaptic plasticity in the hippocampus. These results suggest that YKS might be effective for preventing hippocampus-dependent cognitive deficits with age.

Omega-3 Fatty Acids Supplementation: Therapeutic Potential in a Mouse Model of Stargardt Disease.

Purpose: To evaluate the therapeutic effects of omega-3 (ω3) fatty acids on retinal degeneration in the ABCA4-/- model of Stargardt disease when the blood level of arachidonic acid (AA)/eicosapentaenoic acid (EPA) ratio is between 1 and 1.5. Methods: Eight-month-old mice were allocated to three groups: wild type (129S1), ABCA4-/- untreated, and ABCA4-/- ω3 treated. ω3 treatment lasted 3 months and comprised daily gavage administration of EPA and docosahexaenoic acid (DHA). Blood and retinal fatty acid analysis was performed using gas chromatography to adjust the blood AA/EPA ∼1 to 1.5. Eyecups were histologically examined using transmission electron microscopy and confocal microscopy to evaluate lipofuscin granules and the photoreceptor layer. Retinal N-retinylidene-N-retinylethanolamine (A2E), a major component of retinal pigment epithelium lipofuscin, was quantified using liquid chromatography and tandem mass spectrometry, in addition to retinal proteomic analysis to determine changes in inflammatory proteins. Results: EPA levels increased and AA levels decreased in the blood and retinas of the treatment group. Significantly less A2E and lipofuscin granules were observed in the treatment group. The thickness of the outer nuclear layer was significantly greater in the treatment group (75.66 ± 4.80 µm) than in the wild-type (61.40 ± 1.84 µm) or untreated ABCA4-/- (56.50 ± 3.24 µm) groups. Proteomic analysis indicated lower levels of complement component 3 (C3) in the treatment group, indicative of lower complement-induced inflammatory response. Conclusions: Three months of ω3 supplementation (AA/EPA ∼1-1.5) reduces A2E levels, lipofuscin granules, and C3 levels in the ABCA4-/- mouse model of Stargardt disease, consistent with slowing of the disease.

Glucosamine-Induced Autophagy through AMPK⁻mTOR Pathway Attenuates Lipofuscin-Like Autofluorescence in Human Retinal Pigment Epithelial Cells In Vitro.

Age-related macular degeneration (AMD) is a vision-threatening age-associated disease. The retinal pigment epithelial (RPE) cells phagocytose and digest photoreceptor outer segment (POS). Incomplete digestion of POS leads to lipofuscin accumulation, which contributes to the pathology of the AMD. Autophagy could help reduce the amount of lipofuscin accumulation. In the present study, we evaluated the effects of glucosamine (GlcN), a natural supplement, on the induction of autophagy and POS-derived lipofuscin-like autofluorescence (LLAF) in ARPE-19 cells in vitro, and investigated the potential molecular pathway involved. Our results revealed that GlcN had no effect on phagocytosis of POS at the lower doses. GlcN treatment induced autophagy in cells. GlcN decreased the LLAF in native POS-treated cells, whereas malondialdehyde or 4-hydroxynonenal-modified POS attenuated this effect. 3-Methyladenine inhibited GlcN-induced autophagy and attenuated the effect of GlcN on the decrease of the native POS-derived LLAF. Furthermore, GlcN induced the phosphorylation of AMP-activated protein kinase (AMPK) and inhibited the phosphorylation of mammalian target of rapamycin (mTOR), whereas Compound C inhibited these effects of GlcN. Altogether, these results suggest that GlcN decreased the native POS-derived LLAF through induction of autophagy, at least in part, by the AMPK⁻mTOR pathway. This mechanism has potential for the preventive treatment of lipofuscin-related retinal degeneration such as AMD.

Longevity and Stress Resistant Property of 6-Gingerol from Zingiber officinale Roscoe in Caenorhabditis elegans

In order to discover lifespan-extending compounds made from natural resources, activity-guided fractionation of Zingiber officinale Roscoe (Zingiberaceae) ethanol extract was performed using the Caenorhabditis elegans (C. elegans) model system. The compound 6-gingerol was isolated from the most active ethyl acetate soluble fraction, and showed potent longevity-promoting activity. It also elevated the survival rate of worms against stressful environment including thermal, osmotic, and oxidative conditions. Additionally, 6-gingerol elevated the antioxidant enzyme activities of C. elegans, and showed a dose-depend reduction of intracellular reactive oxygen species (ROS) accumulation in worms. Further studies demonstrated that the increased stress tolerance of 6-gingerol-mediated worms could result from the promotion of stress resistance proteins such as heat shock protein (HSP-16.2) and superoxide dismutase (SOD-3). The lipofuscin levels in 6-gingerol treated intestinal worms were decreased in comparison to the control group. No significant 6-gingerol-related changes, including growth, food intake, reproduction, and movement were noted. These results suggest that 6-gingerol exerted longevity-promoting activities independently of these factors and could extend the human lifespan.

Relation of plasma selenium and lipid peroxidation end products in patients with Alzheimer's disease.

Increased oxidative stress in the brain during the course of Alzheimer's disease (AD) leads to an imbalance of antioxidants and formation of free radical reaction end-products which may be detected in blood as fluorescent lipofuscin-like pigments (LFPs). The aim of this study was to evaluate and compare LFPs with plasma selenium concentrations representing an integral part of the antioxidant system. Plasma samples from subjects with AD dementia (ADD; n=11), mild cognitive impairment (MCI; n=17) and controls (n=12), were collected. The concentration of selenium was measured using atomic absorption spectroscopy. LFPs were analyzed by fluorescence spectroscopy and quantified for different fluorescent maxima and then correlated with plasma selenium. Lower levels of selenium were detected in MCI and ADD patients than in controls (P=0.003 and P=0.049, respectively). Additionally, higher fluorescence intensities of LFPs were observed in MCI patients than in controls in four fluorescence maxima and higher fluorescence intensities were also observed in MCI patients than in ADD patients in three fluorescence maxima, respectively. A negative correlation between selenium concentrations and LFPs fluorescence was observed in the three fluorescence maxima. This is the first study focused on correlation of plasma selenium with specific lipofuscin-like products of oxidative stress in plasma of patients with Alzheimer´s disease and mild cognitive impairment.

Anti-Aging Effect of Riboflavin Via Endogenous Antioxidant in Fruit fly Drosophila Melanogaster.

OBJECTIVES: This study investigated the effect of riboflavin on aging in Drosophila melanogaster (fruit fly). DESIGN: Experimental study. SETTING: Naval Medical Research Institute. PARTICIPANTS: Fruit fly Drosophila melanogaster. INTERVENTION: After lifelong supplement of riboflavin, the lifespan and the reproduction of fruit flies were observed. Hydrogen peroxide (H2O2) was used to mimic oxidative stress damage to fruit flies and the survival time was recorded. MEASUREMENTS: The activity of copper-zinc-containing superoxide dismutase (SOD1), manganese containing SOD (SOD2) and catalase (CAT) and lipofuscin (LF) content were determined. RESULTS: Riboflavin significantly prolonged the lifespan (Log rank χ2=16.677, P<0.001) and increased the reproductive capacity (P<0.01 for day 15; P<0.05 for day 30) of fruit flies by lifelong supplement. The survival time of fruit flies damaged by H2O2 was significantly prolonged (Log rank χ2=15.886, P<0.001), the activity of SOD1 (P<0.01) and CAT (P<0.01) was enhanced, and the accumulation of LF (P<0.01) was inhibited by riboflavin supplement. CONCLUSION: Riboflavin prolonged the lifespan and increased the reproduction of fruit flies through anti-oxidative stress pathway involving enhancing the activity of SOD1 and CAT and inhibiting LF accumulation. Riboflavin deserves more attention for slowing human aging.