ABSTRACT
Ferroptosis is an iron-dependent form of regulated cell death,which is distinct from apoptosis,ne-crosis,and pyroptosis.Recent studies have found that activators of ferroptosis,such as Erastin,can activate autophagy-re-lated proteins,induce the formation of autophagosomes,and ultimately release ferric ions to mediate ferroptosis.This pro-cess,called ferritinophagy,is initiated by the binding of an autophagic cargo receptor protein,nuclear receptor coactivator 4(NCOA4),to iron-laden ferritin.The transfer of NCOA4-ferritin to the lysosome by ferritinophagy results in the proteoly-sis of ferritin,and,in turn,the release of its iron content and lipid-reactive oxygen species(ROS)accumulation.Ferritin-ophagy has been closely associated with central nervous system disorders,circulatory system diseases,and cancer.Fur-thermore,the regulation mechanism of ferritinophagy is also a hot topic in the study of iron-dependent cell death process.With the in-depth study of ferritinophagy,great progress has been made in the study of key components of ferritinophagy as well as its molecular mechanisms and processes.However,a comprehensive summary of the methods for detecting ferritin-ophagy is still unclear.To further deepen the understanding of ferritinophagy and its detection methods,this review focus-es on the concept,characteristics,methods,and precautions during detection of ferritinophagy.This review provided ex-perimental reference for subsequent researchers and promoting the progress of research related to ferritinophagy.
ABSTRACT
A water-soluble fluorescent probe (7-diethyl amino-3-formaldehyde coumarin) for Fe3+ detection was designed and synthesiZed, and its structure was confirmed by 1 HNMR, 13 CNMR and MS spectra.This probe showed high emission intensity at 471 nm.With the continuous addition of Fe3+, the emission intensities at 471 nm decreased gradually, and showed an excellent linearity with Fe3+in the range of 0.02-60 μmol/L, and the regression equation was I=322.56-4.86CFe3+.This probe was able to detect Fe3+ qualitatively and quantitatively with the detection limit as low as 22 nmol/L.Besides, this probe showed high sensitivity to Fe3+over other metal ions.The detection process was reversible, which could be recycled for the Fe3+detection.In terms of good optical properties and the strong fluorescence in physiological pH, the probe was successfully applied in imaging Fe3+ of living Ramos cells.
ABSTRACT
Objective To investigate the effect of music electroacupuncture on perifocal ferric ions and neuronal apoptosis and the brain water content in rats with acute cerebral hemorrhage and explore the mechanism of its action on acute cerebral hemorrhage.Methods One hundred and twenty-eight healthy adult male Wister rats were randomized to normal, model, electroacupuncture and music electroacupuncture groups. In each group, four time points of 6 hrs, 24 hrs, 3 days and 7 days were set up, eight rats each time point. A rat model of acute cerebral hemorrhage was made using collagenase. In the electroacupuncture and music electroacupuncture groups, point Baihui was connected to the anode and point Taiyang to the cathode, 2 voltage was used as a selection parameter and electroacupuncture lasted 30 min. Intracerebral perifocal ferric ions and neuronal apoptosis and the brain water content were measured at four time points of 6 hrs, 24 hrs, 3 days and 7 days after model making.Results Intracerebral ferric ion content was higher in the model, electroacupuncture and music electroacupuncture groups of rats than in the normal group at 6 hrsafter model making (P<0.05), lower in the electroacupuncture and music electroacupuncture groups than in the model group at 24 hrs, 3 and 7 days after model making (P<0.05) and lower in the music electroacupuncture group than in the electroacupuncture group at 3 and 7 days after model making (P<0.05). Intracerebral neuronal apoptosis was higher in the model, electroacupuncture and music electroacupuncture groups of rats than in the normal group at 6 hrs after model making (P<0.05) and lower in the music electroacupuncture group than in the electro- acupuncture group at 7 days after model making (P<0.05). The brain water content was higher in the model, electro- cupuncture and music electroacupuncture groups of rats than in the normal group at 6 and 24 hrs after model making (P<0.05), lower in the electroacupuncture and music electroacupuncture groups than in the model group at 3 days after model making (P<0.05) and lower in the music electroacupuncture group than in the electroacupuncture group at 7 days after model making (P<0.05).Conclusions Music electroacupuncture has a benign regulating effect on intracerebral perifocal ferric ions, inhibits neuronal apoptosis around hematoma in the early stage and reduces cerebral edema in rats with acute cerebral hemorrhage. Its therapeutic effect is superior to that of electroacupuncture.
ABSTRACT
A ball milling method which is green with simple-manipulation and low-cost was used to prepare graphene as precursor for graphene quantum dots (GQDs) synthesis.Subsequently, GQDs with good dispersibility, uniform size distribution, average diameter of (4.80 ± 0.20) nm and 1-3 layers were prepared by one-step hydrothermal method.The morphology, structure and optical properties of the GQDs were characterized by high-resolution transmission electron microscopy (HRTEM), atomic force microscope (AFM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), UV-Vis absorption and fluorescence spectroscopy.Furthermore, the GQDs were used in label-free and specific detection of ferric ion (Fe.3+) with broad linear ranges of 2.0×10.-6-7.0×10.-4 mol/L and low detection limit of 1.8 × 10.6 mol/L (S/N=3).The possible mechanism was also discussed and the application of GQDs for Fe.3+ detection in tap water was demonstrated.Finally, based on their low cytotoxicity and excellent biocompatibility, the as-prepared GQDs were successfully applied to efficient cell imaging.This work provides a new way for preparation of carbon-based nanomaterials and build a foundation for deepening applications of GQDs in bio-/chem-analysis, bioimaging, etc.
ABSTRACT
Plants are natural source of antioxidants which ameliorate a variety of diseases. In this study, we determined the in vitro and in vivo antioxidant activity of methanolic, polyphenolic and sapogenin mixture leaf extracts of Wattakaka volubilis (Linn.f.) Stapf, an ayurvedic medicinal plant. The in vitro antioxidant activity was tested spectrophotometrically by measuring ferric reducing power, DPPH and hydroxyl radical scavenging activity. Whereas the in vivo antioxidant activity was determined by estimation of enzymes catalase, superoxide dismutase (SOD), peroxidase and lipid peroxidation. In vitro study results showed that the tested extracts were capable of reducing ferric ion and scavenging free radical as well as hydroxyl radical. Treatment of mice with single dose of CCl4 resulted in decreased level of catalase, superoxide dismutase (SOD) and peroxidase, but with 3-fold increase in lipid peroxidation. However, pretreatment of mice with methanolic and polyphenolic sample extracts caused prevention of catalase, and peroxidase when compared with control, where as lipid peroxidation was brought back to normal. NOS activity was also found significantly decreased.
ABSTRACT
The seeds of Bixa orellana (Annatto, family Bixaceae), have been used in food coloring for over 50 years. With the aim of introducing its extracts as pharmaceutical colorant, there is the need to investigate the biological and pharmacological activities of the extract. This study was designed to develop extraction protocols for annatto coloring fraction with potential for pharmaceutical application and evaluate the antioxidant activity of the extracts in vitro. Powdered seed material was extracted using acid-base protocols and the crystals obtained were washed with deionized water, oven-dried for about 12 hours at 45 °C and stored in air-tight containers. The in vitro antioxidant activity was tested via 2,2-diphenyl-1- picrylhydrazyl (DPPH) radical scavenging activity and iron (III) oxide reducing power using ascorbic acid (vitamin C) as a reference standard. The free radical scavenging activity of annatto extract ranged from 5.5 % to 48.9 % relative to ascorbic acid (2.9 % to 41.5 %) at respective concentrations between 0.25 and 2.5 μg/ml. Similarly, iron (III) oxide reducing power shows good linear concentration-dependent relation (R2 = 0.9986) comparable with ascorbic acid (R2 = 0.9934). Results generally indicated that Bixa orellana seed extract is a potential source of antioxidants of natural origin.
ABSTRACT
This study demonstrated that the bacteria could adsorb Fe3+ and reduce Fe3+ to Fe2+. Iron had significant bacteriostatic effects, which were directly proportional to the iron concentration and under the influence of pH and chelator. It presumed that the inhibition of Fe3+ acts through the formation of hydroxyl free radicals.