ABSTRACT
The escalating prevalence of metabolic syndrome poses a significant public health challenge, particularly among aging populations, with metabolic dysfunctions contributing to pro-inflammatory states. In this review, we delved into the less recognized association between hyperuricemia (HUA), a manifestation of metabolic syndrome and a primary risk factor for gout, and age-related macular degeneration (AMD), a sight-threatening ailment predominantly affecting the elderly. In recent years, inflammation, particularly its involvement in complement pathway dysregulation, has gained prominence in AMD pathophysiology. The contradictory role of uric acid (UA) in intercellular and intracellular environments was discussed, highlighting its antioxidant properties in plasma and its pro-oxidant effects intracellularly. Emerging evidence suggests a potential link between elevated serum uric acid levels and choroid neovascularization in AMD, providing insights into the role of HUA in retinal pathologies. Various pathways, including crystal-induced and non-crystal-induced mechanisms, were proposed to indicate the need for further research into the precise molecular interactions. The implication of HUA in AMD underscores its potential involvement in retinal pathologies, which entails interdisciplinary collaboration for a comprehensive understanding of its impact on retina and related clinical manifestations.
Subject(s)
Gout , Hyperuricemia , Macular Degeneration , Humans , Hyperuricemia/complications , Hyperuricemia/metabolism , Macular Degeneration/etiology , Macular Degeneration/metabolism , Gout/metabolism , Gout/etiology , Uric Acid/metabolism , Uric Acid/blood , AnimalsABSTRACT
Klotho is known for its age-suppressing function and has been implicated in sarcopenia pathology. It has recently been proposed that the adenosine A2B receptor plays a crucial role in skeletal muscle energy expenditure. However, the association between Klotho and A2B remains elusive. In this study, Klotho knockout mice, aged 10 weeks, and wild-type mice, aged 10 and 64 weeks, were used for comparison in indicators of sarcopenia (n = 6 for each group). PCR was performed to confirm the mice genotypes. Skeletal muscle sections were analyzed using hematoxylin and eosin staining as well as immunohistochemistry staining. The skeletal muscle cross-sectional area was significantly reduced in Klotho knockout mice and wild-type mice, aged 64 weeks, when compared with wild-type mice, aged 10 weeks, with a decreased percentage of type IIa and IIb myofibers. Likely impaired regenerative capacity, as reflected by the reduction of paired box 7 (Pax7)- and myogenic differentiation protein 1 (MyoD)-positive cells, was also observed in Klotho knockout mice and aged wild-type mice. 8-Hydroxy-2-deoxyguanosine expression was enhanced with Klotho knockout and aging, indicating higher oxidative stress. Adenosine A2B signaling was impaired, with a lower expression of the A2B receptor and the cAMP-response element binding protein in Klotho knockout and aged mice. The present study provides the novel finding that sarcopenia involves adenosine signaling under the influence of Klotho knockout.
Subject(s)
Receptor, Adenosine A2B , Sarcopenia , Mice , Animals , Receptor, Adenosine A2B/genetics , Receptor, Adenosine A2B/metabolism , Glucuronidase/metabolism , Loss of Function Mutation , Sarcopenia/genetics , Sarcopenia/metabolism , Sarcopenia/pathology , Muscle, Skeletal/metabolism , Mice, KnockoutABSTRACT
Objective:Cordyceps cicadae, a medicinal fungus, is assessed as having many functions: anti-cancer, anti-fatigue, anti-aging, immune-boosting, renal and liver protection. Since the industrial production of C. cicadae mycelium consistently manufactures bioactive compounds superior to wild fruiting bodies, there is a need to confirm the toxicity of liquid fermented C. cicadae mycelium. Studies showed the toxicity evaluation of C. cicadae mycelium in animal models, but safety reports in clinical studies are scarce. As such, a safety assessment of oral N6-(2-hydroxyethyl) adenosine (HEA-enriched) C. cicadae mycelium in humans is provided here.Method: After 49 participants ingested granules of 1.05 g of freeze-dried C. cicadae mycelium once a day for 3 months, their blood samples were collected at the beginning and end of the experiment for analysis.Results: There were no significant differences between the initial and final measurements in renal and liver function. Also, there was no influence on blood electrolytes as well as blood lipid levels. In clinical observation, there were also no side effects or adverse feelings mentioned by participants.Conclusion: These results suggested that HEA-enriched C. cicadae mycelium produced by liquid fermentation is safe and can be developed as a functional health food.
Subject(s)
Cordyceps , Adenosine , Animals , Humans , Kidney , MyceliumABSTRACT
Objective Vegetarian diets have been shown to increase the risk of certain nutritional deficiencies, such as iron. As a number of patients with chronic kidney disease (CKD) in Taiwan are lacto-ovo vegetarians, the aim of this study was to investigate the effects of different proportions and sources of protein in lacto-ovo vegetarian and omnivorous diets, as well as the influence of adequate dietary protein intake, on renal function and nutritional status of Taiwanese patients with stage 3 to stage 5 CKD. Methods This is a cross-sectional study. In total, 100 outpatients with stage 3 to stage 5 CKD were enrolled in this study, including 40 lacto-ovo vegetarians and 60 omnivores. Subjects were divided into the lacto-ovo vegetarian group and omnivorous group based on dietary protein patterns. The indicators of renal function included estimated glomerular filtration rate (eGFR), creatinine, and blood urea nitrogen (BUN). Albumin, hemoglobin (Hb), and red blood cell count (RBC) measurements served as nutritional indicators. The levels of dietary energy and protein, as well as protein sources (plant or animal), were also analyzed. Results The levels of serum phosphate and triglycerides were significantly lower in the lacto-ovo vegetarian group than in the omnivore group, suggesting that lacto-ovo vegetarian diets have both phosphate-lowering and lipid-lowering effects, which could reduce the development of hyperphosphatemia and dyslipidemia. However, since all groups consumed higher than the recommended amounts of protein diet intake, no significant differences were observed in other renal function indices between the two groups. Conclusion Although a larger cohort study is necessary, the findings of this study could help patients with CKD to make healthier food choices and be used to support future medical nutritional therapies.
Subject(s)
Diet , Kidney/physiology , Renal Insufficiency, Chronic/metabolism , Vegetarians , Aged , Aged, 80 and over , Blood Urea Nitrogen , Creatinine , Female , Glomerular Filtration Rate , Humans , Male , Middle AgedABSTRACT
The Klotho loss-of-function mutation is known to cause accelerated senescence in many organs, but its effects on the cornea have not been published. The present study aims to investigate the effects of the Klotho null mutation on cornea degeneration and to characterize the pathological features. Mouse corneas of Klotho homozygous, heterozygous, and wild-type mice at 8 weeks of age for both genders were subject to pathological and immunohistological examinations. The results show an irregular topography on the corneal surface with a Klotho null mutation. Histological examinations revealed a reduced corneal epithelial cell density, endothelial cell-shedding, and decreased cornea stromal layer thickness in the absence of the Klotho function. Furthermore, guttae formation and the desquamation of wing cells were significantly increased, which was comparable to the characteristics of Fuchs endothelial corneal dystrophy and bullous keratopathy. The mechanism analysis showed multi-fold abnormalities, including oxidative stress-induced cornea epithelium apoptosis and inflammation, extracellular matrix remodeling in the stroma, and a disruption of epithelial repair, presumably through the epithelial-mesenchymal transition. In conclusion, cornea degeneration was observed in the Klotho loss-of-function mutant mice. These pathological features support the use of Klotho mutant mice for investigating age-related cornea anomalies, including Fuchs endothelial corneal dystrophy, bullous keratopathy, and dry eye diseases.
ABSTRACT
Dry eye is a complicated ocular surface disease that causes discomfort, visual disturbance, and frequently observed ocular surface damage. Emerging hypotheses suggest probiotics may help relieve dry eye symptoms by modulating inflammation and oxidative stress. This study aimed to investigate the therapeutic effects of Streptococcus thermophilus iHA318 probiotics on dry eye using in vitro assays and an in vivo murine model of ultraviolet B (UVB) radiation-induced dry eye. In vitro analyses revealed that S. thermophilus iHA318® exhibited antioxidant activity and anti-inflammatory effects by inhibiting reactive oxygen species production and suppressing inflammatory cytokines. For the in vivo study, female ICR mice were assigned to normal control, UVB-induced dry eye, and UVB+iHA318 treatment groups. UVB exposure significantly decreased tear volume and tear film breakup time (TBUT) compared to normal controls. Supplementation with S. thermophilus iHA318® via oral gavage markedly improved tear production and TBUT on day 7 post-UVB exposure. Ocular surface photography demonstrated improved gradings of corneal opacity, smoothness, and lissamine green staining in the iHA318 group versus the UVB group. Topographical analysis further revealed improvement in the UVB-induced corneal irregularities by iHA318 treatment. Collectively, these results indicate that S. thermophilus iHA318 exerts a protective effect against dry eye symptoms by mitigating oxidative stress and inflammation, thereby preserving tear film stability and ocular surface integrity. This probiotic strain represents a promising therapeutic approach for managing dry eye syndrome.
ABSTRACT
PURPOSE: Weekly disposable soft contact lenses have been widely used recently, but their shield effects against ultraviolet (UV) irradiation remain to be evaluated. This study investigated the bioprotective effects of several weekly soft contact lenses against UVB irradiation on the corneal surface in a mouse model. METHODS: Fifty ICR mice were randomly divided into five groups: (1) blank control, (2) exposed to UVB without contact lens protection, (3) exposed to UVB and protected with Vifilcon A contact lenses, (4) exposed to UVB and protected with Etafilcon A contact lenses, and (5) exposed to UVB and protected with HEMA+MA contact lenses. The exposure to UVB irradiation was performed at 0.72 J/cm²)/day after anesthesia for a 7-day period, followed by cornea surface assessment for smoothness, opacity, and grading of lissamine green staining. Tissue sections were prepared for hematoxylin and eosin staining and immunohistochemical detection by using antibodies against myeloperoxidase, cytokeratin-5, P63, Ki-67, nuclear factor-kappa B (p65), cyclooxygenase-2, Fas L, and Fas. RESULTS: The results showed impaired corneal surface with myeloperoxidase+ polymorphonuclear leukocyte infiltration into the stroma after UVB exposure, in contrast to the intact status of the blank controls. The corneas with Etafilcon A and HEMA+MA contact lenses maintained more cells positive for cytokeratin-5, P63, and Ki-67 compared to those with Vifilcon A or without contact lens protection. Furthermore, less proinflammatory factors, including nuclear factor-kappa (p65), cyclooxygenase-2, Fas L, and Fas, were induced in the corneas protected by Etafilcon A and HEMA+MA. CONCLUSIONS: This study demonstrated various protective effects of weekly disposable contact lenses against UVB irradiation. The mouse model used in the present study may be used extensively for in vivo assessment of UV shield efficacy.
Subject(s)
Contact Lenses , Cornea/radiation effects , Ultraviolet Rays , Animals , Cell Death/radiation effects , Cornea/pathology , Epithelial Cells/pathology , Epithelial Cells/radiation effects , Epithelium, Corneal/pathology , Epithelium, Corneal/radiation effects , Female , Inflammation Mediators/metabolism , Lens, Crystalline/pathology , Lens, Crystalline/radiation effects , Leukocytes, Mononuclear/pathology , Leukocytes, Mononuclear/radiation effects , Mice , Mice, Inbred ICR , Models, Animal , Surface Properties/radiation effectsABSTRACT
Purpose: Current ocular surface diagnostic methods may not totally meet and implement the clinical demands for early and precise treatments. The tear ferning (TF) test has been known as a quick, simple, and inexpensive procedure. This study aimed to validate the TF test as an alternative method for early determination of photokeratitis status. Methods: The tear sample was collected from the UVB-induced photokeratitis eyes and processed for TF formation. The TF patterns were graded by both the Masmali and a Sophie-Kevin (SK) grading criteria, a new set of criteria modified from the Masmali grading, for differential diagnoses. In addition, the TF test results were correlated with three clinical ocular surface indicators, including tear volume (TV), tear film break-up time (TBUT), and cornea staining, to evaluate the diagnostic capacity. Results: Differential diagnosis between the normal and the photokeratitis status was achieved by the TF test. The SK grading reflected earlier photokeratitis status than the Masmali grading criteria. The TF results were strongly correlated with the three clinical ocular surface indicators, particularly for the TBUT and cornea staining. Conclusions: The TF test was proven to have a capacity to distinguish photokeratitis from the normal status at an early stage by using the SK grading criteria. It is therefore potentially useful for photokeratitis diagnosis in the clinical settings. Translational Relevance: The TF test may fulfill the demands of precise and early diagnosis to facilitate in time the intervention for photokeratitis.
Subject(s)
Eye , Keratitis , Animals , Mice , Keratitis/diagnosis , TearsABSTRACT
The Klotho null mutation is known to lead to accelerated aging in many organs, but its effects on tear secretion and lacrimal gland (LG) senescence have not been addressed. This study investigated whether the Klotho null mutation would lead to a dry eye status and the outcome of LG without Klotho function. The Klotho (-/-) mutant mice showed reduced LG size and tear volume on the 8th week, as compared to their littermates (+/+, +/-). Hematoxylin-Eosin and Masson's trichrome staining were performed to determine morphological changes and collagen deposition. Traits of LG aging, including acinar atrophy, thickened capsules, and more collagen depositions, were observed. Immunohistochemical detections for Klotho, α-SMA, MDA, 8-OHdG, vasoactive intestinal polypeptide (VIP), tyrosine hydroxylase (TH), MMP-2, MMP-9, and FGF-23 were performed and compared among the three genotypes (+/+, +/-, -/-) at 6 and 8 weeks of age for mechanism analyses. Unexpectedly, the Klotho protein was not detected in the LG of all the three genotypes, indicating indirect effects from the Klotho null mutation. Further analyses showed abundant MDA and 8-OHdG detected in the Klotho (-/-) LG on the 8th week, indicating elevated oxidative stress. In addition, both sympathetic and parasympathetic neural transducing activities, as represented by TH and VIP expression, respectively, and α-SMA were increased in LGs with Klotho mutations. Furthermore, MMP-2 and MMP-9 expression were elevated, with FGF-23 expression being decreased on the 8th week in the Klotho (-/-) LG. In conclusion, characteristics of age-related LG degeneration were found in the Klotho null mutant mice. These traits support the use of Klotho mutant mice as a model of age-related dry eye disease.
ABSTRACT
Cataracts, a prevalent age-related eye condition, pose a significant global health concern, with rising rates due to an aging population and increased digital device usage. In Taiwan, cataract prevalence is particularly high, reaching up to 90% among individuals aged 70 and above. The lens of the eye absorbs short-wave light, which can lead to oxidative stress in lens epithelial cells and contribute to cataract formation. Exposure to ultraviolet (UV) light further exacerbates the risk of cataracts by generating reactive oxygen species. Heat-shock proteins (HSPs), involved in protein maintenance and repair, have been linked to cataract development. Cordyceps cicadae (C. cicadae), a traditional Chinese medicine, has a long history of use and is known for its pharmacological effects. N6-(2-hydroxyethyl) adenosine (HEA), a bioactive compound found in C. cicadae, exhibits anti-inflammatory, immunomodulatory, and neuroprotective properties. Previous studies have shown that C. cicadae mycelial extracts improve dry eye disease and reduce intraocular pressure in animal models. Additionally, C. cicadae possesses antioxidant properties, which are beneficial for combating cataract formation. In this study, we aim to evaluate the preventive efficacy of C. cicadae mycelial extracts in UV-induced cataract development. By investigating the ameliorative effects of C. cicadae on eye diseases and its potential role in ocular health improvement, we hope to uncover new options for cataract prevention and provide insights into the mechanisms of action. The findings of this research could provide a novel approach for nutritional supplements targeting cataract prevention, offering potential benefits in the field of ocular health.
Subject(s)
Cataract , Cordyceps , Mice , Animals , Antioxidants/pharmacology , Oxidative Stress , Adenosine , Cataract/etiology , Cataract/prevention & controlABSTRACT
Angiostrongylus cantonensis (A. cantonensis) is the most common cause of parasitic eosinophilic meningitis worldwide. By using an animal model of BALB/c mice infected with A. cantonensis, previous studies indicated that the anthelmintic drug, albendazole, could kill A. cantonensis larvae and prevent further infection. However, the dead larvae will induce severe immune responses targeting at brain tissues. To alleviate the detrimental effects caused by the dead larvae, we administered curcumin, a traditional anti-inflammatory agent, as a complementary treatment in addition to albendazole therapy, to determine whether curcumin could be beneficial for treatment. The results showed that although curcumin treatment alone did not reduce worm number, combined treatment by albendazole and curcumin helped to reduce eosinophil count in the cerebrospinal fluid, better than using albendazole alone. This alleviating effect did not affect albendazole treatment alone, since histological analysis showed similar worm eradication with or without addition of curcumin. Nevertheless, curcumin treatment alone and combined albendazole-curcumin treatment did not inhibit MMP-9 expression in the brain tissue. In conclusion, curcumin, when used as a complementary treatment to albendazole, could help to alleviate eosinophilic meningitis through suppression of eosinophil count in the cerebrospinal fluid.
Subject(s)
Albendazole/therapeutic use , Angiostrongylus cantonensis/drug effects , Anthelmintics/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Curcumin/therapeutic use , Eosinophilia/drug therapy , Meningitis/drug therapy , Strongylida Infections/drug therapy , Albendazole/administration & dosage , Animals , Anthelmintics/administration & dosage , Anti-Inflammatory Agents/administration & dosage , Brain/drug effects , Brain/immunology , Brain/parasitology , Curcumin/administration & dosage , Disease Models, Animal , Drug Therapy, Combination , Eosinophilia/cerebrospinal fluid , Eosinophilia/parasitology , Eosinophils/drug effects , Larva/drug effects , Leukocyte Count , Matrix Metalloproteinase 9/biosynthesis , Meningitis/cerebrospinal fluid , Meningitis/parasitology , Mice , Mice, Inbred BALB C , Strongylida Infections/cerebrospinal fluid , Strongylida Infections/parasitologyABSTRACT
Purpose: Metabolic disorders have been implicated in ocular diseases, such as age-related macular degeneration (AMD) and diabetic retinopathy (DR). Recently, hyperuricemia (HUA) has been proposed as another risk factor for AMD, although no cause-and-effect experimental data have been published. In this study, we investigated whether HUA would initiate AMD or related retinal damages in hyperuricemic mice. Methods: HUA was induced in male ICR mice by dietary supplements of uric acid and oxonic acid potassium salt, with or without treatments by allopurinol or benzbromarone for various durations. Serum uric acid and angiotensin II concentrations were measured by enzyme-linked immunosorbent assay (ELISA) at regular intervals. The retinal damages were assessed by hematoxylin and eosin staining, immunostaining, and TUNEL assay. The cause-and-effect of HUA was compared among the study groups. Results: The results showed that the total thickness of photoreceptor inner and outer segments, as well as the thickness of the photoreceptor outer segment alone, were reduced under HUA. Furthermore, HUA elevated serum angiotensin II, which indicated activation of the renin-angiotensin system (RAS), leading to higher matrix metalloproteinase-2 (MMP-2) expression, and glial activation in the ganglion cell layer. HUA also led to the reduction of retinal pigment epithelium gap junction protein connexin-43 and apoptosis. Uric acid lowering agents, allopurinol or benzbromarone, were effective in ameliorating the impairments. Conclusions: HUA may pose as a causative factor of retinal injuries. The reduction of serum uric acid may reduce the detrimental effects caused by HUA.
Subject(s)
Hyperuricemia , Macular Degeneration , Allopurinol/pharmacology , Angiotensin II , Animals , Benzbromarone/pharmacology , Hyperuricemia/drug therapy , Macular Degeneration/complications , Male , Matrix Metalloproteinase 2 , Mice , Mice, Inbred ICR , Uric AcidABSTRACT
Dry eye disease (DED), a multifactorial inflammatory ocular surface disorder, affects up to 50% of individuals over 50 years old worldwide and is one of the most common reasons for seeking ophthalmologic care. Generally, topical eye drops or oral drugs are administered to treat DED; however, the use of preservatives in eye drops or the adverse effects of oral drugs are disadvantageous for long-term therapy. Cordyceps cicadae, a traditional Chinese medicinal fungus, possesses anti-inflammatory effects without evident toxicity and is obtainable at low price. Our previous study demonstrated that C. cicadae mycelium effectively ameliorates dry eye symptoms in the benzalkonium chloride (BAC)-induced mouse dry eye model by increasing tear volume and tear film breakup time (TBUT). However, the effects of C. cicadae mycelium for human dry eye amelioration remains unknown. Thus, the present study investigated the mitigation of dry eye conditions and related discomforts through oral supplementation of fermented C. cicadae mycelium. A total of 70 healthy individuals were recruited and randomly allocated to receive a daily oral dose of 1,050 mg preparation in sachet containing either freeze-dried C. cicadae mycelium powder with 0.3 mg of adenosine and 1.5 mg of HEA per gram or placebo for 90 days. The participants were subjected to anthropometric measurements, dry eye questionnaires (DEQ), Schirmer's tests, intraocular pressure (IOP) measurements, tear film breakup time (TBUT) tests, tear osmolality measurements, and tear electrolyte analysis prior to and right after completion of the study. The results showed a significantly increased TBUT as well as a significant decrease in tear osmolarity, in parallel with the decrease of tear electrolytes, especially Na+ and Cl ions. Although significant increase of tear volume was not observed, the increased TBUT suggests mitigation of dry eye through improvement of tear quality. Therefore, C. cicadae mycelium supplementation may be used for dry eye alleviation as a novel therapeutic intervention.
Subject(s)
Cordyceps , Dry Eye Syndromes , Humans , Animals , Mice , Middle Aged , Pilot Projects , Dry Eye Syndromes/drug therapy , Dry Eye Syndromes/diagnosis , Ophthalmic Solutions/therapeutic use , Mycelium , Dietary SupplementsABSTRACT
PURPOSE: Ultraviolet B (UVB) irradiation activates nuclear factor-kappa B (NF-κB) and inducible nitric oxide synthase (iNOS) in the cornea, resulting in inflammatory responses and malondialdehyde (MDA) accumulation. This study aims to determine the effect of zerumbone, a potent NF-κB inhibitor and inflammation modulators, on UVB-induced corneal damages in a mouse model. METHODS: Fifty female imprinting control region (ICR) mice were randomly divided into five groups. The mice were anaesthetized with their ocular surfaces exposed to UVB light (0.72J/cm(2)/daily), followed by daily dietary zerumbone supplements at 0, 1, 10, and 100 mg/kg of bodyweight. Mice without zerumbone supplements were used as treatment controls and mice without UVB irradiation as blank controls. Corneal surface damages were graded according to smoothness, opacity, and the extent of lissamine green staining. Histopathological changes were also examined, along with the expression of NF-κB, iNOS, and tumor necrosis factor-α (TNF-α). MDA accumulation and the levels of two antioxidant enzymes, glutathione (GSH) and GSH reductase (GR) were also examined. RESULTS: UVB irradiation caused significant damages to cornea, including sustained inflammation, apparent corneal ulcer, and severe epithelial exfoliation, leading to thinning of corneal epithelial layer, and infiltration of polymorphonuclear leukocytes. NF-κB expression was highly activated with nuclear translocation. The expression of iNOS and TNF-α were increased. MDA accumulation was also increased in both the corneal epithelial layer and the stroma. With dietary zerumbone, corneal damages were ameliorated in a dose-dependent manner. NF-κB activation and its nuclear translocation were blocked with decreased expression of iNOS and TNF-α. Infiltration of polymorphonuclear leukocytes was also blocked by dietary zerumbone. Besides, MDA accumulation was reduced with concomitant increase of GSH and GR levels. CONCLUSIONS: Dietary zerumbone prevents UVB-induced corneal damages by inhibition of NF-κB, iNOS, and TNF-α, with concomitant reduction of MDA accumulation and increase of GSH and GR levels in the mouse model. Results of this study suggest that dietary zerumbone may be used as a prophylactic agent against UVB-induced photokeratitis.
Subject(s)
Cornea/drug effects , Diet Therapy/methods , Keratitis/diet therapy , NF-kappa B/antagonists & inhibitors , Nitric Oxide Synthase Type II/antagonists & inhibitors , Sesquiterpenes , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Animals , Cornea/pathology , Cornea/radiation effects , Corneal Topography , Dose-Response Relationship, Drug , Female , Gene Expression , Glutathione/analysis , Glutathione/biosynthesis , Glutathione Reductase/analysis , Keratitis/etiology , Keratitis/genetics , Keratitis/metabolism , Keratitis/pathology , Lissamine Green Dyes/analysis , Malondialdehyde/analysis , Mice , Mice, Inbred Strains , Models, Animal , NF-kappa B/genetics , NF-kappa B/metabolism , Neutrophil Infiltration/drug effects , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/metabolism , Sesquiterpenes/administration & dosage , Sesquiterpenes/therapeutic use , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism , Ultraviolet Rays/adverse effectsABSTRACT
PURPOSE: Hyperhomocysteinemia is known to cause degeneration of retinal ganglion cells, but its influence on photoreceptors remains largely unknown. In particular, the role of homocysteine-thiolactone (Hcy-T)--the physiologic metabolite of homocysteine that has been proven to be more cytotoxic than homocysteine itself--as a factor that causes retinopathy, has not been defined. This study aimed to investigate the toxic effects of excessive Hcy-T in a mouse model. METHODS: A total of 60 six-week-old female ICR mice were used in this study. The mice were divided into 3 experimental groups and 2 control groups. The mice in the experimental groups were subjected to intravitreal injections of Hcy-T to reach final estimated intravitreal concentrations at 5, 25, and 200 µM, respectively. Mice without injection (blank) and with 0.9 NaCl injections (sham injection) were used as controls. The mice with 200 µM Hcy-T were sacrificed at days 7, 15, 45, and 90 after injection and the mice with 5 or 25 µM Hcy-T were sacrificed at day 90, with the controls sacrificed at day 15 or 90 for comparison. Semi-quantitative dot-blot analysis was performed for confirmation of retinal homocysteinylation. The mouse retinas were evaluated microscopically, with the thickness of total and specific retinal layers determined. Immunohistochemical analysis was performed and the labeled cells were quantified to determine the effects of excessive Hcy-T on specific retinal cells. RESULTS: Dose-dependent retinal homocysteinylation after Hcy-T injection was confirmed. The homocysteinylation was localized in the outer and inner segments of photoreceptors and the ganglion cell layer (GCL). Retinal cell degenerations were found in the GCL, inner nuclear layer, and outer nuclear layer at day 90 after 200 µM Hcy-T injection. Significant thickness reduction was found in the total retina, outer nuclear layer, and the outer and inner segment layers. A trend of thickness reduction was also found in the GCL and inner nuclear layer, although this was not statistically significant. The rhodopsin⺠photoreceptors and the calbindin⺠horizontal cells were significantly reduced at day 15, and were nearly ablated at day 90 after 200 µM Hcy-T injection (p<0.001 for both day 15 and day 90), which was not seen in the sham injection controls. The Chx-10⺠or the Islet-1⺠bipolar cells and the Pax-6⺠amacrine cells were severely misarranged at day 90, but no significant reduction was found for both cell types. The GFAP⺠Müller cells were activated at day 15, but were not significantly increased at day 90 after the injection. CONCLUSIONS: Excessive retinal homocysteinylation by Hcy-T, a condition of hyperhomocysteinemia, could lead to degeneration of photoreceptors, which might lead to retinopathies associated with severe hyperhomocysteinemia or diabetes mellitus.
Subject(s)
Homocysteine/analogs & derivatives , Photoreceptor Cells/pathology , Retina/pathology , Retinal Degeneration , Retinal Ganglion Cells/pathology , Animals , Calbindins , Diabetic Retinopathy/metabolism , Diabetic Retinopathy/pathology , Dose-Response Relationship, Drug , Eye Proteins/analysis , Eye Proteins/biosynthesis , Female , Glial Fibrillary Acidic Protein , Homeodomain Proteins/analysis , Homeodomain Proteins/biosynthesis , Homocysteine/administration & dosage , Homocysteine/adverse effects , Hyperhomocysteinemia/metabolism , Hyperhomocysteinemia/pathology , Immunoblotting , Immunohistochemistry , Intravitreal Injections , LIM-Homeodomain Proteins/analysis , LIM-Homeodomain Proteins/biosynthesis , Mice , Mice, Inbred ICR , Nerve Tissue Proteins/analysis , Nerve Tissue Proteins/biosynthesis , PAX6 Transcription Factor , Paired Box Transcription Factors/analysis , Paired Box Transcription Factors/biosynthesis , Photoreceptor Cells/drug effects , Photoreceptor Cells/metabolism , Repressor Proteins/analysis , Repressor Proteins/biosynthesis , Retina/drug effects , Retina/metabolism , Retinal Degeneration/chemically induced , Retinal Degeneration/metabolism , Retinal Degeneration/pathology , Retinal Ganglion Cells/drug effects , Retinal Ganglion Cells/metabolism , Rhodopsin/analysis , Rhodopsin/biosynthesis , S100 Calcium Binding Protein G/analysis , S100 Calcium Binding Protein G/biosynthesis , Transcription Factors/analysis , Transcription Factors/biosynthesisABSTRACT
PURPOSE: To investigate the preventive effect of dietary zerumbone against UVB-induced cataractogenesis. METHODS: A total of 50 six-week-old female ICR mice were split into five groups (each contained 10 mice) and exposed to UVB (0.72 J/cm(2)/daily) at noon for 7 days, except for the blank control group. The mice with UVB exposure were fed with zerumbone as a dietary supplement at 0, 1, 10, and 100 mg/kg of bodyweight, respectively, starting from one day before UVB exposure. On day 7, at 4 h after UVB exposure, all mice were subjected to cataract examination and lens opacity scoring, in correlation with levels of MDA (malondialdehyde), GSH (glutathione), GR (GSH reductase), GPx (glutathione peroxidase), and SOD (superoxide dismutase) in the lens. RESULTS: Dietary zerumbone at 100 mg/kg after UVB exposure was effective in decreasing lens opacity scores (p<0.001) and to reduce MDA (p<0.001), while GSH and GR levels were significantly increased (both p<0.001) in the lens. SOD was also increased with dietary zerumbone at 100 mg/kg (p=0.115), whereas GPx (p=0.171) levels were lower as compared with those without zerumbone after UVB exposure. CONCLUSIONS: These results suggest that zerumbone may protect against UVB-induced cataractogensis through reducing lipid peroxides and enhancing the endogenous antioxidant GSH level and GR activity.
Subject(s)
Cataract/prevention & control , Diet , Sesquiterpenes/pharmacology , Ultraviolet Rays , Animals , Antioxidants/metabolism , Cataract/chemically induced , Cataract/enzymology , Female , Glutathione/metabolism , Glutathione Peroxidase/metabolism , Glutathione Reductase/metabolism , Lens, Crystalline/drug effects , Lens, Crystalline/enzymology , Lens, Crystalline/pathology , Lens, Crystalline/radiation effects , Malondialdehyde/metabolism , Mice , Mice, Inbred ICR , Sesquiterpenes/chemistry , Superoxide Dismutase/metabolismABSTRACT
BACKGROUND: Hedgehog signalling has been implicated in prostate tumorigenesis in human subjects and mouse models, but its effects on transforming normal basal/stem cells toward malignant cancer stem cells remain poorly understood. METHODS: We produced pCX-shh-IG mice that overexpress Hedgehog protein persistently in adult prostates, allowing for elucidation of the mechanism during prostate cancer initiation and progression. Various markers were used to characterize and confirm the transformation of normal prostate basal/stem cells into malignant cancer stem cells under the influence of Hedgehog overexpression. RESULTS: The pCX-shh-IG mice developed prostatic intraepithelial neoplasia (PIN) that led to invasive and metastatic prostate cancers within 90 days. The prostate cancer was initiated through activation of P63+ basal/stem cells along with simultaneous activation of Hedgehog signalling members, suggesting that P63+/Patch1+ and P63+/Smo+ cells may serve as cancer-initiating cells and progress into malignant prostate cancer stem cells (PCSCs). In the hyperplastic lesions and tumors, the progeny of PCSCs differentiated into cells of basal-intermediate and intermediate-luminal characteristics, whereas rare ChgA+ neuroendocrine differentiation was seen. Furthermore, in the metastatic loci within lymph nodes, kidneys, and lungs, the P63+ PCSCs formed prostate-like glandular structures, characteristic of the primitive structures during early prostate development. Besides, androgen receptor (AR) expression was detected heterogeneously during tumor progression. The existence of P63+/AR-, CK14+/AR- and CD44+/AR- progeny indicates direct procurement of AR- malignant cancer trait. CONCLUSIONS: These data support a cancer stem cell scenario in which Hedgehog signalling plays important roles in transforming normal prostate basal/stem cells into PCSCs and in the progression of PCSCs into metastatic tumor cells.
Subject(s)
Gene Expression Regulation, Neoplastic , Hedgehog Proteins/metabolism , Neoplastic Stem Cells/metabolism , Prostatic Neoplasms/metabolism , Receptors, Androgen/biosynthesis , Signal Transduction , Animals , Disease Models, Animal , Hedgehog Proteins/genetics , Male , Mice , Mice, Inbred ICR , Neoplasm Metastasis , Neoplastic Stem Cells/pathology , Phosphoproteins/genetics , Phosphoproteins/metabolism , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Receptors, Androgen/genetics , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolism , Smoothened Receptor , Trans-Activators/genetics , Trans-Activators/metabolismABSTRACT
Purpose: Analysis of ferning formation after tear drop desiccation on a glass slide has been applied as a simple method to examine tear normality and is referred to as the tear ferning (TF) test. Despite use of the TF test in clinical settings and in some animals, thus far no TF test protocol has been developed for the mouse model. This study aimed to establish a mouse TF test protocol that can be used for dry eye research using the mouse as the study model. Methods: Tear samples were collected from 24 healthy mice after repeated flushes with 2, 5, 10, or 20 µL wash solutions, either 0.9% NaCl saline or sterile water, on the ocular surface. After sample collection, TF tests were performed at variable drop volumes (2-20 µL), at a relative humidity of either 46% ± 2% or 53% ± 2%, and with temperature fixed at 24°C ± 2°C for comparison. Moreover, the influence of osmolarity (between 280 and 360 mOsm/L) and pH values (6.5-8.0) and the effect of centrifugation (4000 rpm, 10 minutes) on ferning formation were examined. Reproducibility and ferning storage stability were also determined. Results: An optimized protocol was established with relative humidity at 46% ± 2% and drop aliquot at 2 µL, using 0.9% NaCl saline as the wash solution. Using sterilized water as the wash solution did not result in any crystalloid formation. Centrifugation did not aid ferning formation in any of the samples. Higher osmolarity increased ferning formation from grades between 0 to 1 to grades between 2 to 3, but pH values that varied between 6.5 and 8.0 did not affect ferning formation. The established mouse TF test protocol also displayed reproducibility and storage stability. Conclusions: A TF test protocol for the mouse model was established that could be used for comparative analyses under various ocular surface disease conditions. Translational Relevance: This mouse TF test protocol will facilitate the application of basic research into the mouse model to clinical care.
Subject(s)
Dry Eye Syndromes , Tears , Animals , Dry Eye Syndromes/diagnosis , Eye , Mice , Osmolar Concentration , Reproducibility of ResultsABSTRACT
OBJECTIVE: To investigate the efficacy and safety of three H. erinaceus mycelia (EAHE) capsules (350 mg/capsule; containing 5 mg/g erinacine A active ingredient) per day for the treatment of patients with mild Alzheimer's Disease (AD). METHODS: This study comprised a 3-week no-drug screening period, followed by a 49-week double-blind treatment period with 2-parallel groups in which eligible patients were randomized to either three 5 mg/g EAHE mycelia capsules per day or identical appearing placebo capsules. Cognitive assessments, ophthalmic examinations, biomarker collection, and neuroimaging were followed throughout the study period. RESULTS: After 49 weeks of EAHE intervention, a significant decrease in Cognitive Abilities Screening Instrument score was noted in the placebo group, a significant improvement in Mini-Mental State Examination score was observed in the EAHE group and a significant Instrumental Activities of Daily Living score difference were found between the two groups. In addition, EAHE group achieved a significantly better contrast sensitivity when compared to the placebo group. Moreover, only the placebo group observed significantly lowered biomarkers such as calcium, albumin, apolipoprotein E4, hemoglobin, and brain-derived neurotrophic factor and significantly elevated alpha1-antichymotrypsin and amyloid-beta peptide 1-40 over the study period. Using diffusion tensor imaging, the mean apparent diffusion coefficient (ADC) values from the arcuate fasciculus region in the dominant hemisphere significantly increased in the placebo group while no significant difference was found in the EAHE group in comparison to their baselines. Moreover, ADC values from the parahippocampal cingulum region in the dominant hemisphere significantly decreased in the EAHE group whereas no significant difference was found in the placebo group when compared to their baselines. Lastly, except for four subjects who dropped out of the study due to abdominal discomfort, nausea, and skin rash, no other adverse events were reported. CONCLUSION: Three 350 mg/g EAHE capsules intervention for 49 weeks demonstrated higher CASI, MMSE, and IADL scores and achieved a better contrast sensitivity in patients with mild AD when compared to the placebo group, suggesting that EAHE is safe, well-tolerated, and may be important in achieving neurocognitive benefits. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT04065061.
ABSTRACT
PURPOSE: Congenital eye malformations are a leading cause of blindness in children. Influenza virus infections prevail worldwide and have been implicated in congenital defects. Infections acquired during gestation may disrupt eye morphogenesis. We investigated the effects of influenza B virus infection on eye malformations during early embryogenesis. METHODS: Chick embryos were exposed to influenza B virus at Hamburger-Hamilton stage 9. Maternal infection was conducted by exposing pregnant ICR mice to influenza B virus at the embryonic gestation stage E 5.0. After infection, virus RNA distribution was detected by in situ hybridization at various developmental stages. The distribution of periocular neural crest cells and the extent of apoptosis were examined by immunohistochemical staining, in correlation with eye malformations. RESULTS: Microphthalmos and anophthalmos, together with neural tube defects, were found in the chick and mouse embryos following the infections. The viral RNA was detected in the head neuroepithelium, optic vesicle, periocular mesenchyme, and the forming ventricles of the developing brain. Immunohistochemical staining revealed aberrant neural crest distribution and extensive apoptosis in the head surface ectoderm, periocular mesenchyme, and optic vesicle in the chick embryos. Furthermore, transplacental infection was confirmed by the presence of viral RNA in the mouse fetuses, with eye and neural tube defects similar to those found in the chick embryos after experimental infections. CONCLUSIONS: Influenza B virus may act as a teratogen to cause aberrant periocular neural crest cell contribution to eye development and extensive apoptosis, resulting in congenital eye malformations.