Chronic Sleep Deprivation Impairs Visual Functions via Oxidative Damage in Mice.

Sleep deprivation (SD) is a global public health burden, and has a detrimental role in the nervous system. Retina is an important part of the central nervous system; however, whether SD affects retinal structures and functions remains largely unknown. Herein, chronic SD mouse model indicated that loss of sleep for 4 months could result in reductions in the visual functions, but without obvious morphologic changes of the retina. Ultrastructural analysis by transmission electron microscope revealed the deterioration of mitochondria, which was accompanied with the decrease of multiple mitochondrial proteins in the retina. Mechanistically, oxidative stress was provoked by chronic SD, which could be ameliorated after rest, and thus restore retinal homeostasis. Moreover, the supplementation of two antioxidants, α-lipoic acid and N-acetyl-l-cysteine, could reduce retinal reactive oxygen species, repair damaged mitochondria, and, as a result, improve the retinal functions. Overall, this work demonstrated the essential roles of sleep in maintaining the integrity and health of the retina. More importantly, it points towards supplementation of antioxidants as an effective intervention strategy for people experiencing sleep shortages.

Extraction and characterization of cyclic lipopeptides with antifungal and antioxidant activities from Bacillus amyloliquefaciens.

AIMS: This study aimed to isolate active substances from metabolites of Bacillus amyloliquefaciens SJ100001 and examine their antifungal activity against Fusarium oxysporum (F. oxysporum) SJ300024 screened from the root-soil of cucumber wilt. METHODS AND RESULTS: An active substance, anti-SJ300024, was obtained from the fermentation broth of strain SJ100001 by reversed-phase silica gel and gel chromatography, and further got its chemical structure as cyclic lipopeptide Epichlicin through nuclear magnetic resonance (NMR) and mass spectrometry (MS). In vitro experiments showed that Epichlicin had a better inhibitory rate (67.46%) against the strain SJ300024 than the commercially available fungicide hymexazol (45.10%) at the same concentration. The MTT assays proved that Epichlicin was non-cytotoxic, besides it also had good free radical scavenging ability and total reducing ability. CONCLUSIONS: Epichlicin isolated from strain SJ100001 can effectively control F. oxysporum SJ300024 screened from the root-soil of cucumber wilt. SIGNIFICANCE AND IMPACT OF THE STUDY: Epichlicin may be used as an environmentally friendly and efficient biocontrol agent for controlling Fusarium wilt of cucumber and reducing crop losses. More importantly, the non-cytotoxicity of Epichlicin can avoid harm to consumers. Additionally, Epichlicin has broad application prospects in medicine due to its antioxidant properties.

Antimicrobial activity and acting mechanism of Tegillarca granosa hemoglobin-derived peptide (TGH1) against Vibrio parahaemolyticus.

Vibrio parahaemolyticus is a Gram-negative bacterium and the one of leading causal agent of human foodborne diseases such as gastroenteritis upon consumption of raw, or contaminated marine products. There is an increased interest in the use of antimicrobial peptides (AMPs) as alternative food preservatives to prevent foodborne diseases. In this study, bioinformatics tools were used to predict and screen AMPs derived from hemoglobin of blood clam (Tegillarca granosa). A novel AMP, T. granosa hemoglobin-derived peptide (TGH1), was identified and its antimicrobial effect and mechanism of action on V. parahaemolyticus was explored. The minimal inhibitory concentration (MIC) of TGH1 on V. parahaemolyticus was 12.5 µg/mL. Transmission electron microscopy (TEM) revealed that TGH1 kills bacteria by perforating the cell wall perforation and destroying integrity of the cell membrane. Similarly, laser confocal microscopy confirmed that TGH1 entered bacterial cells by aggregating on the cell surface to destroy the cell. In addition, TGH1 increased the inner-membrane permeability of V. parahaemolyticus in a concentration-dependent manner, as well as prevented biofilm formation. Moreover, TGH1 has 55.6% ß-sheet (antiparallel) structure and has no cytotoxic effects on normal human hepatocytes. Thus, peptide TGH1 has good potential use and application in antimicrobial control of foodborne pathogens.

[Evaluation of LOXL1 polymorphisms in exfoliation syndrome in the Uygur population].

OBJECTIVE: In this study, we evaluate the association profiles of the lysyl oxidase-like 1 ( LOXL1) gene polymorphisms with exfoliation syndrome in XFS Uygur population. METHODS: Case-control study. Sixty-four unrelated Uygur patients with XFS (including 7 patients with Exfoliation Syndrome Glaucoma) and 127 Uygur control subjects were included. All of control subjects were selected from the same area, passed through the same ophthalmic checks and confirmed without any expressions of XFS. Most of them suffered from cataract and other ophthalmic disease.Genotypes of the three single nucleotide polymorphisms (SNPs) of LOXL1 (rs1048661, rs2165241 and rs3825942) were analyzed by direct sequencing following PCR amplification, and a case-control association study was performed and judged by odd ratio (OR) with (95% confidential interval). RESULTS: G allele of rs1048661 [OR:1.92 (1.14-3.22)], G of rs3825942 [OR:4.86 (2.02-11.68)], and T of rs2165241[OR:3.98 (2.54-6.25)] were risk alleles for the disorder. The genotypes TT for rs2165241 [OR:2.20 (1.04-4.65)] were risk genotypes for the disease. CONCLUSION: LOXL1 is a susceptibility gene of XFS in the Uygur populations. The risk alleles of rs1048661, rs3825942 and rs2165241 in Uygur subjects were identified to be significantly associated with XFS individually.

Identification of Tyrosinase Inhibitory Peptides from Sea Cucumber (Apostichopus japonicus) Collagen by in silico Methods and Study of their Molecular Mechanism.

AIMS: Identify novel tyrosinase inhibitory peptides from sea cucumber (Apostichopus japonicus) collagen using in silico methods and elucidate the molecular interaction mechanism. BACKGROUND: Tyrosinase is a key enzyme in the melanin biosynthesis pathway, to restrain melanin production and reduce the appearance of associated skin diseases, inhibition of tyrosinase activity is one of the most effective methods. OBJECTIVE: The collagen from Apostichopus japonicus, which consists of 3,700 amino acid residues, was obtained from the National Center for Biotechnology Information (NCBI) as the accession number of PIK45888. METHOD: Virtual hydrolyzed method was used, and the peptides generated were compared to the previously established BIOPEP-UWM database. In addition, peptides were examined for their solubility, toxicity, and tyrosinase-binding capacity. RESULT: A tripeptide CME with optimal potential inhibitory activity against tyrosinase was identified, and its inhibitory activity was validated by in vitro experiments. The IC50 value of CME was 0.348 ± 0.02 mM for monophenolase, which was inferior to the positive control peptide glutathione, while it had an IC50 value of 1.436 ± 0.07 mM for diphenolase, which was significantly better than glutathione, and the inhibition effect of CME on tyrosinase was competitive and reversible. CONCLUSION: In silico methods were efficient and useful in the identification of new peptides.

[Survey of blindness and low vision among residents in Shuimogou District, Urumqi, China in 2010].

OBJECTIVE: To estimate the prevalence of visual impairment among adults aged ≥ 40 years, compare the prevalence between Uyghur and Han residents and analyze the causes of visual impairment. METHODS: Population-based cluster sampling survey was conducted among a target population of 5032 persons ≥ 40 years of age from Shuimogou District in Urumqi, Xinjiang Uyghur Autonomous Region. Distance visual acuity (VA) was measured with a Tumbling-E chart at 5 m. Presenting and best corrected VA were recorded. Clinical evaluations were performed. And primary causes of visual impairment was determined for those with VA < 0.3. RESULTS: Among them, there were 4104 responders (Uyghur 2006 persons, Han 2098 persons) with a response rate 81.56%. Prevalence of bilateral blindness was 1.25%/1.86% (Uyghur/Han) (P < 0.05) and bilateral low vision 4.04%/3.29% (Uyghur/Han) (P < 0.05). Primary cause of visual impairment among participants was cataract (cause proportion of 49.23% among Uyghurs and 51.85% among Hans). Visual impairment was correlated with advanced age, males and poor literacy. Prevalences of bilateral blindness and bilateral low vision in age group 40 - 50 yr increased from 0.48% and 1.13% to 3.47% and 10.88% in age group ≥ 70 among Uygur citizens respectively (χ(2) = 22.36, P < 0.05 vs χ(2) = 70.97, P < 0.05). Relative data among the Han citizens varied from 0% and 1.42% to 4.39% and 7.89% (χ(2) = 27.94, P < 0.05 vs χ(2) = 39.99, P < 0.05). CONCLUSION: The most frequent cause of visual impairment in this area is cataract (Uyghur 49.23% vs Han 51.85%) while retinal diseases and glaucoma are important causes as well. Blindness prevention programs targeting the elderly should be expanded, particularly in areas with a limited access and affordability of eye care services.

Synergistic Effect of Carbonate Apatite and Autogenous Bone on Osteogenesis.

Bone augmentation using artificial bone is an important option in dental defect prostheses. A bone substitute using carbonate apatite (CO3Ap), an inorganic component of bone, was reported to have promising bone formation and bone replacement ability. However, the osteoinductivity of artificial bone is less than autogenous bone (AB). In this study, CO3Ap with AB is demonstrated as a clinically effective bone substitute. For in vitro experiments, an osteoclast-like cell (RAW-D) was cultured in the presence of AB, CO3Ap, or both (Mix), and the number of osteoclasts was evaluated. Osteoblasts were also cultured under the same conditions, and the number of adherent cells was evaluated. For in vivo experiments, a few holes were created in the rat tibia and AB, CO3Ap, or Mix were added. At 0, 14, and 21 days, the tissue morphology of the wound area was observed, and the thickness of the cortical bone was measured. In vitro, Mix did not increase the number of osteoclasts or osteoblasts. However, in vivo, the rate of bone replacement remarkably increased with Mix on dome-shape. A bone-grafting material combining osteoinductive AB with abundant artificial bone is expected to be clinically easy to use and able to form bone.

Multiple Gene Polymorphisms Associated with Exfoliation Syndrome in the Uygur Population.

BACKGROUND: Our previous data suggested that three single-nucleotide polymorphisms (SNPs), rs1048661, rs3825942, and rs2165241, of the lysyl oxidase-like 1 gene (LOXL1) are significantly associated with exfoliation syndrome (XFS) and exfoliation glaucoma (XFG). The following study investigated other SNPs that potentially effect XFS/XFG. METHODS: A total of 216 Uygur patients diagnosed with XFS/XFG, and 297 Uygur volunteers were admitted to the First Affiliated Hospital at Xinjiang Medical University between January 2015 and October 2017. Blood samples were collected by venipuncture. Alleles and genotypes of LOXL1, TBC1D21, ATXN2, APOE, CLU, AFAP1, TXNRD2, CACNA1A, ABCA1, GAS7, and CNTNAP2 were analyzed by direct sequencing. RESULTS: The allele G of rs41435250 of LOXL1 was a risk allele for XFS/XFG (P < 0.001), whereas the allele G of rs893818 of LOXL1 was a protective allele for XFS/XFG (P < 0.001). After adjusting all data for age and gender, the following results were obtained: the frequency of genotype CC for rs7137828 of ATXN2 was significantly higher in XFS/XFG patients than in controls (P = 0.027), while no significance was found with reference to the frequency of genotype TT. The frequency of genotype GG for rs893818 of LOXL1 (P < 0.001) and the frequency of genotype AA were both significantly higher in XFS/XFG groups compared to the control group (P < 0.001). In addition, the frequency of genotype TT for rs41435250 of LOXL1 was higher in XFS/XFG patients than in controls (P = 0.003), while no significant difference was found with reference to the frequency of genotype GG after adjusting for age and gender. In addition, the haplotypes G-A/T-G/G-G for rs41435250 and rs893818 were significantly associated with XFS/G. CONCLUSIONS: With reference to LOXL1, the rs41435250 resulted as a risk factor and rs893818 as a protective factor for XFS/XFG in the Uygur populations. Meanwhile, the rs16958445 of TBC1D21 and the rs7137828 of ATXN2 have also shown to be associated with pathogenesis of XFS/XFG.

Histopathological changes in retinas and F-ERG features of streptozotocin-induced diabetic rats treated with ozone.

AIM: To study the histopathological changes in the retina and flash electroretinogram (F-ERG) features of ozone-treated streptozotocin (STZ)-induced diabetic rats. METHODS: Seventy male Sprague Dawley rats were grouped as follows: blank group (GB, n=10), model control group (GM, n=18), ozone group (GO3, n=19), and oxygen group (GO2, n=18). The model was induced by single intraperitoneal injection of STZ. Ozone or oxygen enteroclysm was given twice per week for 4wk. F-ERG and histopathological examinations were performed one month after treatment. RESULTS: Under dark adaption, as compared to GB, the other groups each had differential decreases in the a-wave amplitudes (P<0.05); the latencies were delayed in GM, GO2, and GO3 rats (P<0.05). Similar results were observed under light adaption, with the exception that the a-wave of the amplitudes (F=0.28, P>0.05). There were significant differences in the apoptosis index among the groups (P<0.05). Under ozone treatment, apoptosis was decreased in GO3 as compared to GM and GO2. CONCLUSION: Ozone administration alleviates nerve damage and reduces pathology and apoptosis in the retinas of diabetic rats.