scholarly journals Dose-Dependent Neuroprotective Effects of Bovine Lactoferrin Following Neonatal Hypoxia–Ischemia in the Immature Rat Brain

Nutrients ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 3880
Author(s):  
Eduardo Sanches ◽  
Yohan van de Looij ◽  
Sadou Sow ◽  
Audrey Toulotte ◽  
Analina da Silva ◽  
...  

Injuries to the developing brain due to hypoxia–ischemia (HI) are common causes of neurological disabilities in preterm babies. HI, with oxygen deprivation to the brain or reduced cerebral blood perfusion due to birth asphyxia, often leads to severe brain damage and sequelae. Injury mechanisms include glutamate excitotoxicity, oxidative stress, blood–brain barrier dysfunction, and exacerbated inflammation. Nutritional intervention is emerging as a therapeutic alternative to prevent and rescue brain from HI injury. Lactoferrin (Lf) is an iron-binding protein present in saliva, tears, and breast milk, which has been shown to have antioxidant, anti-inflammatory and anti-apoptotic properties when administered to mothers as a dietary supplement during pregnancy and/or lactation in preclinical studies of developmental brain injuries. However, despite Lf’s promising neuroprotective effects, there is no established dose. Here, we tested three different doses of dietary maternal Lf supplementation using the postnatal day 3 HI model and evaluated the acute neurochemical damage profile using 1H Magnetic Resonance Spectroscopy (MRS) and long-term microstructure alterations using advanced diffusion imaging (DTI/NODDI) allied to protein expression and histological analysis. Pregnant Wistar rats were fed either control diet or bovine Lf supplemented chow at 0.1, 1, or 10 g/kg/body weight concentration from the last day of pregnancy (embryonic day 21–E21) to weaning. At postnatal day 3 (P3), pups from both sexes had their right common carotid artery permanently occluded and were exposed to 6% oxygen for 30 min. Sham rats had the incision but neither surgery nor hypoxia episode. At P4, MRS was performed on a 9.4 T scanner to obtain the neurochemical profile in the cortex. At P4 and P25, histological analysis and protein expression were assessed in the cortex and hippocampus. Brain volumes and ex vivo microstructural analysis using DTI/NODDI parameters were performed at P25. Acute metabolic disturbance induced in cortical tissue by HIP3 was reversed with all three doses of Lf. However, data obtained from MRS show that Lf neuroprotective effects were modulated by the dose. Through western blotting analysis, we observed that HI pups supplemented with Lf at 0.1 and 1 g/kg were able to counteract glutamatergic excitotoxicity and prevent metabolic failure. When 10 g/kg was administered, we observed reduced brain volumes, increased astrogliosis, and hypomyelination, pointing to detrimental effects of high Lf dose. In conclusion, Lf supplementation attenuates, in a dose-dependent manner, the acute and long-term cerebral injury caused by HI. Lf reached its optimal effects at a dose of 1 g/kg, which pinpoints the need to better understand effects of Lf, the pathways involved and possible harmful effects. These new data reinforce our knowledge regarding neuroprotection in developmental brain injury using Lf through lactation and provide new insights into lactoferrin’s neuroprotection capacities and limitation for immature brains.

Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1156
Author(s):  
Madelaine Sugasti-Salazar ◽  
Yessica Y. Llamas-González ◽  
Dalkiria Campos ◽  
José González-Santamaría

Mayaro virus (MAYV) hijacks the host’s cell machinery to effectively replicate. The mitogen-activated protein kinases (MAPKs) p38, JNK, and ERK1/2 have emerged as crucial cellular factors implicated in different stages of the viral cycle. However, whether MAYV uses these MAPKs to competently replicate has not yet been determined. The aim of this study was to evaluate the impact of MAPK inhibition on MAYV replication using primary human dermal fibroblasts (HDFs) and HeLa cells. Viral yields in supernatants from MAYV-infected cells treated or untreated with inhibitors SB203580, SP600125, U0126, or Losmapimod were quantified using plaque assay. Additionally, viral protein expression was analyzed using immunoblot and immunofluorescence. Knockdown of p38⍺/p38β isoforms was performed in HDFs using the PROTACs molecule NR-7h. Our data demonstrated that HDFs are highly susceptible to MAYV infection. SB203580, a p38 inhibitor, reduced MAYV replication in a dose-dependent manner in both HDFs and HeLa cells. Additionally, SB203580 significantly decreased viral E1 protein expression. Similarly, knockdown or inhibition of p38⍺/p38β isoforms with NR-7h or Losmapimod, respectively, affected MAYV replication in a dose-dependent manner. Collectively, these findings suggest that p38 could play an important role in MAYV replication and could serve as a therapeutic target to control MAYV infection.


Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 985
Author(s):  
Luisa Müller ◽  
Nicole Power Guerra ◽  
Jan Stenzel ◽  
Claire Rühlmann ◽  
Tobias Lindner ◽  
...  

Caloric restriction (CR) slows the aging process, extends lifespan, and exerts neuroprotective effects. It is widely accepted that CR attenuates β-amyloid (Aβ) neuropathology in models of Alzheimer’s disease (AD) by so-far unknown mechanisms. One promising process induced by CR is autophagy, which is known to degrade aggregated proteins such as amyloids. In addition, autophagy positively regulates glucose uptake and may improve cerebral hypometabolism—a hallmark of AD—and, consequently, neural activity. To evaluate this hypothesis, APPswe/PS1delta9 (tg) mice and their littermates (wild-type, wt) underwent CR for either 16 or 68 weeks. Whereas short-term CR for 16 weeks revealed no noteworthy changes of AD phenotype in tg mice, long-term CR for 68 weeks showed beneficial effects. Thus, cerebral glucose metabolism and neuronal integrity were markedly increased upon 68 weeks CR in tg mice, indicated by an elevated hippocampal fluorodeoxyglucose [18F] ([18F]FDG) uptake and increased N-acetylaspartate-to-creatine ratio using positron emission tomography/computer tomography (PET/CT) imaging and magnet resonance spectroscopy (MRS). Improved neuronal activity and integrity resulted in a better cognitive performance within the Morris Water Maze. Moreover, CR for 68 weeks caused a significant increase of LC3BII and p62 protein expression, showing enhanced autophagy. Additionally, a significant decrease of Aβ plaques in tg mice in the hippocampus was observed, accompanied by reduced microgliosis as indicated by significantly decreased numbers of iba1-positive cells. In summary, long-term CR revealed an overall neuroprotective effect in tg mice. Further, this study shows, for the first time, that CR-induced autophagy in tg mice accompanies the observed attenuation of Aβ pathology.


1987 ◽  
Vol 252 (2) ◽  
pp. G237-G243
Author(s):  
R. E. Bailey ◽  
R. A. Levine ◽  
J. Nandi ◽  
E. H. Schwartzel ◽  
D. H. Beach ◽  
...  

The lipid profile of isolated gastric superficial epithelial cells (SEC) was evaluated by proton nuclear magnetic resonance spectroscopy (1H-NMR). The most conspicuous resonance band in SEC spectra was due to the protons of +N(CH3)3 groups of phosphatidylcholine and, to a lesser degree, other phospholipid derivatives, on the basis of their chemical shift and addition of purified phospholipids. NMR of cell lysates and phospholipid extracts of SEC in deutero-chloroform provided further spectral resolution of these components. Phospholipase or ethanol treatments of SEC produced membrane disorganization reflected as increased peak intensity of the phospholipid signals. In addition, ethanol, in a dose-dependent manner, attenuated paranitrophenyl phosphatase activity, which correlated with inhibition of total and ouabain-sensitive 86Rubidium chloride uptake by SEC. This study suggests that NMR used in conjunction with other biochemical techniques can monitor SEC membrane structure-function relationships. NMR is a potentially powerful noninvasive probe to show changes in lipid membrane organization induced by low concentrations of ethanol (1%) and may indicate an early sign of "cytotoxicity" in intact SEC.


1993 ◽  
Vol 71 (5-6) ◽  
pp. 321-325 ◽  
Author(s):  
Morikuni Takigawa ◽  
Hiroshi Maeda ◽  
Kenichi Ueyama ◽  
Hidefumi Tominaga ◽  
Kei Matsumoto

The effect of long-term methamphetamine (MAP) treatment on intracranial self-stimulation of the lateral hypotholamus and locomotor traces was assessed. An attempt was made to provide a useful animal model for understanding anhedonia, stereotypy, and reoccurrence of liability, which are analogous to symptoms of schizophrenia. The frequency of intracranial self-stimulation (ICSS) as used as a measure of the animals' "hedonic–anhedonic" state. Following long-term MAP treatment (3 mg/kg), rats gradually showed stereotyped behavior, and became inactive and unresponsive to ICSS. These behavioral changes and decreased ICSS lasted several weeks after cessation of chronic MAP treatment and seemed to suggest post-MAP chronic psychosis and (or) anhedonia, two of the negative symptoms of schizophrenia. The traces of rat behavior affected by chronic MAP treatment were classified into three types, peripheral, mixed, and fixed, occurring in a dose-dependent manner. Reverse tolerance, similar to the reoccurrence of schizophrenic symptoms, was observed as a fixed stereotypy associated with loss of ICSS. These abnormal phenomena were suppressed by pretreatment with haloperidol. In the present study, the combination of ICSS and locomotor trace affected by chronic MAP treatment was proposed as an animal model of schizophrenia and as a useful technique for gauging the effect of neuroleptics.Key words: self-stimulation, anhedonia, stereotypy, reverse tolerance, animal disease model, schizophrenia, methamphetamine.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
M C Carbajo-García ◽  
A Corachán ◽  
M Segura ◽  
J Monleón ◽  
J Escrig ◽  
...  

Abstract Study question Is DNA methylation reversion through DNA methyltransferases (DNMT) inhibitors, such as 5-aza–2’-deoxycitidine, a potential therapeutic option for treatment of patients with uterine leiomyomas (UL)? Summary answer 5-aza–2’-deoxycitidine reduces proliferation and extracellular matrix (ECM) formation by inhibition of Wnt/ β-catenin pathway on UL cells, suggesting DNMT inhibitors as an option to treat UL. What is known already: UL is a multifactorial disease with an unclear pathogenesis and inaccurate treatment. Aberrant DNA methylation have been found in UL compared to myometrium (MM) tissue, showing hypermethylation of tumor suppressor genes, which contributes to the development of this tumor. The use of DNMT inhibitors, such as 5-aza–2’-deoxycytidine (5-aza-CdR), has been suggested to treat tumors in which altered methylation pattern is related to tumor progression, as occurs in UL. Based on this, we aimed to evaluate whether DNA methylation reversion through 5-aza-CdR reduces cell proliferation and ECM formation in UL cells, being a potential option for UL medical treatment. Study design, size, duration Prospective study comparing UL versus MM tissue and human uterine leiomyoma primary (HULP) cells treated with/without 5-aza-CdR at 0 µM (control), 2 µM, 5 µM and 10 µM for 72 hours. UL and MM tissue were collected from women without any hormonal treatment for the last 3 months (n = 16) undergoing myomectomy or hysterectomy due to symptomatic leiomyoma pathology. Participants were recruited between January 2019 and February 2020 at Hospital Universitario y Politecnico La Fe (Spain). Participants/materials, setting, methods Samples were collected from Caucasian premenopausal women aged 31–48 years, with a body mass index of < 30 and without hormonal treatment. DNMT1 gene expression was analysed in UL vs MM tissue by qRT-PCR and activity of DNMT was measured in UL and MM tissue and cells by ELISA. 5-aza-CdR effect on proliferation was assessed by CellTiter test and Western blot (WB), apoptosis and ECM analyzed by WB and Wnt/ β-catenin pathway by qRT-PCR and WB. Main results and the role of chance: DNMT1 gene expression was increased in UL compared to MM tissue (fold change [FC]=2.49, p-value [p]=0.0295). Similarly, DNMT activity was increased in both UL compared to MM tissue and HULP cells versus MM cells (6.50 vs 3.76 OD/h/mg, p = 0.026; 211.30 vs 63.67 OD/h/mg, p = 0.284, respectively). After 5-aza-CdR treatment, cell viability of HULP cells was reduced in a dose dependent manner, being statistically significant at 10 µM (85.25%, p = 0.0001). Accordantly, PCNA protein expression was significantly decreased at 10 µM in HULP cells (FC = 0.695, p = 0.034), demonstrating cell proliferation inhibition. Additionally, 5-aza-CdR inhibited ECM protein expression in HULP cells in a dose-dependent manner being statistically significant at 10 µM for COLLAGEN I (FC = 0.654, p = 0.023) and PAI–1 (FC = 0.654, p = 0.023), and at 2 µM and 10 µM for FIBRONECTIN (FC = 0.812, p = 0.020; FC = 0.733, p = 0.035; respectively). Final targets of Wnt/ β-catenin pathway were decreased after 5-aza-CdR treatment, protein expression of WISP1 was significantly inhibited at 10 µM (FC = 0.699, p = 0.026), while expression levels of Wnt/ β-catenin target genes C-MYC (FC = 0.745, p = 0.028 at 2 µM; FC = 0.728, p = 0.019 at 10 µM) and MMP7 (FC = 0.520, p = 0.003 at 5 µM, FC = 0.577, p = 0.007 at 10 µM) were also significantly downregulated in HULP-treated cells vs untreated cells. Limitations, reasons for caution: This study has strict inclusion criteria to diminish epigenetic variability, thereby we should be cautious extrapolating our results to general population. Besides, this is a proof of concept with the inherent cell culture limitations. Further studies are necessary to determine 5-aza-CdR dose and adverse effects on UL in vivo. Wider implications of the findings: 5-aza-CdR treatment reduces cell proliferation and ECM formation through Wnt/ β-catenin pathway inhibition, suggesting that inhibition of DNA methylation could be a promising new therapeutic approach to treat UL. Trial registration number Not applicable


2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Constantino Tomas-Sanchez ◽  
Victor Manuel Blanco-Alvarez ◽  
Juan Antonio Gonzalez-Barrios ◽  
Daniel Martinez-Fong ◽  
Guadalupe Garcia-Robles ◽  
...  

Acute and subacute administration of zinc exert neuroprotective effects in hypoxia-ischemia animal models; yet the effect of chronic administration of zinc still remains unknown. We addressed this issue by injecting zinc at a tolerable dose (0.5 mg/kg weight, i.p.) for 14 days before common carotid artery occlusion (CCAO) in a rat. After CCAO, the level of zinc was measured by atomic absorption spectrophotometry, nitrites were determined by Griess method, lipoperoxidation was measured by Gerard-Monnier assay, and mRNA expression of 84 genes coding for cytokines, chemokines, and their receptors was measured by qRT-PCR, whereas nitrotyrosine, chemokines, and their receptors were assessed by ELISA and histopathological changes in the temporoparietal cortex-hippocampus at different time points. Long-term memory was evaluated using Morris water maze. Following CCAO, a significant increase in nitrosative stress, inflammatory chemokines/receptors, and cell death was observed after 8 h, and a 2.5-fold increase in zinc levels was detected after 7 days. Although CXCL12 and FGF2 protein levels were significantly increased, the long-term memory was impaired 12 days after reperfusion in the Zn+CCAO group. Our data suggest that the chronic administration of zinc at tolerable doses causes nitrosative stress, toxic zinc accumulation, and neuroinflammation, which might account for the neuronal death and cerebral dysfunction after CCAO.


2001 ◽  
Vol 21 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Gutemberg G. Alves ◽  
Luis Maurício T. R. Lima ◽  
Maely P. Fávero-Retto ◽  
Adriana P. Lemos ◽  
Carlos E. Peres-Sampaio ◽  
...  

The plasma membrane (Ca2++Mg2+)ATPase hydrolyzes pseudo-substrates such as p-nitrophenylphosphate. Except when calmodulin is present, Ca2+ ions inhibit the p-nitrophenylphosphatase activity. In this report it is shown that, in the presence of glycerol, Ca2+ strongly stimulates phosphatase activity in a dose-dependent manner. The glycerol- and Ca2+-induced increase in activity is correlated with modifications in the spectral center of mass (average emission wavenumber) of the intrinsic fluorescence of the enzyme. It is concluded that the synergistic effect of glycerol and Ca2+ is related to opposite long-term hydration effects on the substrate binding domain and the Ca2+ binding domain.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 4824-4824
Author(s):  
Yiqing Li ◽  
Songmei Yin ◽  
Shuangfeng Xie ◽  
Danian Nie ◽  
Liping Ma ◽  
...  

Abstract Abstract 4824 Recent studies have shown that prostaglandin E2 (PGE2) may play a key role in the tumorigenesis and tumor development. Membrane-bound prostaglandin E2 synthase-1 (mPGES-1), an inducible enzyme that acts downstream of cyclooxygenase (COX) and specifically catalyzes the conversion of prostaglandin H2 (PGH2) to PGE2, was over-expression in a variety of solid tumor cells and tissues such as nonsmall-cell lung cancer, colon carcinoma, gastric carcinoma and breast cancer. MK886, a small molecular inhibitor, is a reasonable potency as an inhibitor of mPGES-1 in vitro experiment. In this study, we examined effects of MK886 on expression of mPGES-1 and PGE2 synthesis in human acute myeloid leukemia cell line (HL-60), observed cell proliferation and apoptosis after 24-h treatment with MK886, and tried to explore the possible mechanisms by checking some protein belong AKT cell singling pathway such as P-AKT, Bax and Bcl-2. We found that the expression levels of mPGES-1 mRNA and protein were higher in HL-60 cells than in normal mononuclearcells (MNC). MK886 inhibited mPGES-1 mRNA and protein expression and reduced PGE2 secretion in HL-60 cells in a dose-dependent manner. The cell proliferation was inhibited and the IC50 was 132.16μmol/L. With the increase of MK886 concentration, the cell apoptosis rate assayed by flow cytometry increased and the apparent apoptotic bodies increased when staining by Hoechst 33258. After treated with MK886 for 24h, protein was extracted and assayed by western blot. The results showed that the expression levels of P-AKT, Bcl-2 and c-myc decreased while the Bax protein expression increased in a dose-dependent manner. The caspase-3 activity, determined by colorimetric detection, also increased dose-dependently. These results indicated that mPGES-1 over-expressed in leukemia cell line HL-60, MK886 could induce apoptosis in HL-60 cells via reducing mPGES-1 expression and PGE2 synthesis dose-dependently, thereby regulate the AKT pathway including Bcl-2 family and the activity of caspase-3. It suggested that mPGES-1 inhibitor might emerge as an important therapeutic tool for leukemia treatment. Disclosures: No relevant conflicts of interest to declare.


1983 ◽  
Vol 61 (12) ◽  
pp. 2698-2702 ◽  
Author(s):  
Steven R. Scadding

The objective of this experiment was to determine the effect of retinoic acid on the process of limb regeneration in the African clawed frog, Xenopus laevis. Limbs were bilaterally amputated through the radio-ulna and then treated for 15 days with retinoic acid in the aquarium water, at 3, 15, or 75 IU/mL. The retinoic acid inhibited limb regeneration in a dose-dependent manner, reduced the length of the regenerates, and produced irregularities in the morphogenesis of the cartilage rod in the regenerate. The regenerated limbs were removed after 150 days by amputation through the humerus, and the limbs were again allowed to regenerate. In the retinoic acid treated animals, despite the fact that retinoic acid treatment had been discontinued over 4 months previously, limb regeneration was still inhibited. These results suggest that retinoic acid has a long-term effect on the treated animals.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Zheng-Fei Yan ◽  
Nai-Xu Liu ◽  
Xin-Xin Mao ◽  
Yu Li ◽  
Chang-Tian Li

Flammulina velutipesmycorrhizae have increasingly been produced with increasing ofF. velutipesproduction. A mouse model was thus used to examine potential effect ofF. velutipesmycorrhizae on the immune function. Fifty female Wistar mice (5-weeks-old) weighed 15–20 g were randomly allocated into five groups. Polysaccharide ofF. velutipesmycorrhizae were treated with mice and mice spleen lymphocytes. The levels of CD3+, CD4+, and CD8+T lymphocyte, interleukin-2 (IL-2), and tumor necrosis factor-a (TNF-α) were determined. The results showed that the proportions of CD3+, and CD4+T lymphocyte, the ratio of CD4+/CD8+, and the levels of IL-2 and TNF-a were significantly increased in polysaccharide ofF. velutipesmycorrhizae, while the proportion of CD8+T lymphocyte was decreased in polysaccharide ofF. velutipesmycorrhizae-dose dependent manner. Our findings indicated that a long term exposure of polysaccharide ofF. velutipesmycorrhizae could activate the T lymphocyte immune function. Polysaccharide ofF. velutipesmycorrhizae was expected to develop into the immune health products.


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