Blueberry anthocyanins extract attenuates oxidative stress and angiogenesis on an in vitro high glucose-induced retinopathy model through the miR-33/GLCCI1 axis

Background:Diabetes retinopathy(DR)is a complication of diabetes that affects patients’vision.Previous studies have found blueberry anthocyanins extract(BAE)can inhibit the progression of DR,but its mechanism is not completely clear.Methods:To study the role of BAE in diabetes retinopathy,we treated human retinal endothelial cells(HRCECs)with 30 mM high glucose to simulate the microenvironment of diabetes retinopathy and used BAE to intervene the in vitro high glucose-induced retinopathy model.HRCEC cell viability and apoptosis rates were examined by Cell Counting Kit 8(CCK-8)assay and flow cytometry assay.The binding sites between miR-33 and glucocorticoid-induced transcript 1(GLCCI1)were assessed by luciferase reporter assay.Retinal neovascularization and oxidative stress contribute to diabetic retinopathy.The tubule formation assay was applied to detect the retinal neovascularization.The oxidative stress in the HRCECs was manifested by the reactive oxygen species(ROS)level,the malondialdehyde(MDA)level,and the superoxide dismutase(SOD)activity.Results:Compared with HRCECs cells cultured under normal conditions,high glucose(HG)can induce oxidative stress in HRCRCs,specifically manifested in the increase of ROS and MDA levels,and the decrease of SOD activity.BAE relieved the tubule formation in n the HRCEC.BAE also relieved the ROS and MDA levels and increased the SOD activity.Luciferase reporter assay revealed that GLCCI1 is a target molecule downstream of miR-33.In HRCEC,BAE significantly inhibited the expression of miR-33 induced by HG.miR-33 mimic inhibited the BAE’s effects on oxidative stress and angiogenesis in an in vitro high glucose-induced retinopathy model.Conclusion:BAE alleviated the oxidative stress and microangiogenesis of HRCEC by regulating the miR-33/GLCCI1 axis.

Anthocyanins extracted from Chinese blueberry （Vaccinium uliginosum L.） and its anticancer effects on DLD-1 and COLO205 cells

Background Vaccinium uliginosum L. is a type of blueberry found in the Chinese Changbai Mountains. We extracted Vaccinium uliginosum Anthocyanins （Av.uli） to investigate its bioactivity on suppressing cancer cells. Methods Av.lli was extracted under different conditions of temperature （10℃-35℃）, pH 1.0-3.0, and diatomaceous earth （1.0 g-3.0 g）, followed by a HPLC analysis for the determination of the ingredients. Its anticancer bioactivities on human colon and colorectal cancer cells （DLD-1 and COLO205） were compared with those on Lonicera caerulea Anthocyanins （AL.cae） and Vaccinium myrtillus Anthocyanins （Av.myr）, using cell viability assays, DNA electrophoresis and nuclear morphology assays. Results The optimum process of Av.uli extraction involved conditions of temperature 20℃, pH 2.0, and diatomaceous earth 1.0 g/50 g of fruit weight. Av.uli contained 5 main components： delphinidin （40.70±1.72）%, cyanidin （3.40±0.68）%, petunidin （17.70±0.54）%, peonidin （2.90±0.63）% and malvidin （35.50±1.11）%. The malvidin percentage was significantly higher （P 〈0.05） than it in Av.myr. Av.uli complied with a dose-dependent repression of cancer cell proliferation with an IC50 （50% inhibitory concentration） value of 50 μg/ml, and showed greater anticancer efficiency than AL. cae and Av. myr under the same cell treatment conditions. These observations were further supported by the results of nuclear assays. Conclusions The extraction protocol and conditions we used were effective for anthocyanin extraction. Av.uli could be a feasible practical research tool and a promising therapeutic source to suppress human colon or colorectal cancers.

Protective effects of blueberry anthocyanin extracts on hippocampal neuron damage induced by extremely low-frequency electromagnetic field

The protective effects of blueberry anthocyanin extracts against damage induced by extremely lowfrequency electromagnetic field(ELF-EMF)were investigated in a rat model.Wistar rats were exposed to ELF-EMF with or without the administration of blueberry anthocyanin extracts(50,100,and 200 mg/kg per day intragastrically once a day)for 30 days.Blueberry anthocyanin extracts supplementation inhibited the decrease in Nissl substance levels,cell membrane integrity,and mitochondrial membrane potential induced by ELF-EMF;prevented the increase in nitric oxide,malondialdehyde,and Ca2+concentrations;suppressed superoxide dismutase and glutathione depletion;and enhanced the cognitive ability of the rats exposed to ELF-EMF.The protective effects of blueberry anthocyanin extracts against hippocampal neuron injury caused by ELF-EMF were dose-dependent.These results demonstrated that blueberry anthocyanin extracts suppress hippocampal neuron injury caused by ELF-EMF by inhibiting cell membrane damage and oxidative stress pathways,and suggested that blueberry anthocyanin treatment potentially prevents hippocampal neuron injury.

Inhibitory effect of Gardenblue blueberry (Vaccinium ashei Reade) anthocyanin extracts on lipopolysaccharide-stimulated inflammatory response in RAW 264.7 cells

Blueberries are a rich source of anthocyanins, which are associated with health benefits contributing to a reduced risk for many diseases. The present study identified the functional Gardenblue blueberry （Vaccinium ashei Reade） anthocyanin extracts （GBBAEs） and evaluated their capacity and underlying mechanisms in protecting murine RAW 264.7 cells from lipopolysaccharide （LPS）-stimulated inflammation in vitro. Enzyme-linked immunosorbent assay （ELISA） kit results showed that GBBAEs significantly inhibited the production of nitric oxide （NO）, prostaglandin E2 （PGE2）, interleukin-6 （IL-6）, IL-113, and interferon-y （INF-y）. Real-time polymerase chain reaction （PCR） analysis in- dicated that the mRNA expression levels of IL-6, IL-113, tumor necrosis factor-α （TNF-α）, monocyte chemoattractant protein-1 （MCP-1）, and cyclooxygenase 2 （COX-2） were suppressed in LPS-stimulated RAW 264.7 cells. Additionally, Western blot analysis was used to evaluate the relative protein expression levels of COX-2 and nuclear factor-κB p65 （NF-κBp65）. All these results suggested the potential use of GBBAEs as a functional food for the treatment of in- flammatory diseases.