Achieving improved control of foliar diseases of sesame (Sesamum indicum L.) intercropped with maize (Zea mays L.) through foliar spray of plant extracts

Field trials were conducted to evaluate the effect of foliar spray of aqueous extracts of Tithonia diversifolia or Ocimum gratissimum on Cercospora leaf spot (CLS) and Alternaria leaf blight (ALB) diseases of sesame intercropped with maize. Spraying regime was at 2 weeks interval from 3 weeks after planting (WAP) until 12 WAP. Extracts of T. diversifolia or O. gratissimum reduced the incidence and severity of both diseases. CLS incidence and severity as well as defoliation was significantly (p < 0.05) reduced below what obtained in the unsprayed intercrop. ALB lesion size was significantly (p < 0.05) reduced by T. diversifolia extract at 8.0% (w/v) from 154.7 mm² (sole crop) or 13.4 mm² (unsprayed intercrop) to 4.9 mm² (sprayed intercrop). T. diversifolia extract at 8.0% (w/v) enhanced higher values of grain yield/plant and incidence of normal seeds, and lower incidence of fungal infection of seeds than in the unsprayed intercrop.     

Efficacy of plants extracts from the Cerrado against adult female of <Emphasis Type="Italic">Dermacentor nitens</Emphasis> (Acari: Ixodidae)

Dermacentor nitens tick is commonly found in the equine auditory canal, where it causes economic losses due to its direct damage, causing blood spoliation, stress, transmission of pathogens, and predisposition to myasis and secondary bacterial infection in its hosts. In this study we evaluated the effect of ethanolic extracts of Cerrado plants on biological parameters of engorged females of D. nitens. Ethanolic extracts were prepared from the leaves of Schinopsis brasiliensis, Piptadenia viridiflora, Ximenia americana, and Serjania lethalis at 25–150 mg mL^?1. Groups of 10 engorged adult females were treated with these extracts and compared with a control containing distilled water and another control with organophosphate, using five replicates for each group. Compared with the control with water, S. lethalis and X. americana extracts at 100 and 150 mg mL^?1 significantly inhibited the posture ability. Differently, extracts of S. brasiliensis and P. viridiflora were the most effective in inhibiting larval hatching. Extracts of X. americana and P. viridiflora showed effective inhibition of reproductive parameters of the tick, presenting dose-dependent effect with IC₉₀ 78.86 and 78.94 mg mL^?1, respectively. Theses effective extracts contained low condensed tannin levels and their HPLC chromatograms revealed the presence of flavonoids. The efficacies of P. viridiflora and X. americana extracts were higher than 90% indicating that these extracts are promising as alternative agents for D. nitens control.     

Effects of Tithonia diversifolia (Hemsl.) A. Gray Extract on Adipocyte Differentiation of Human Mesenchymal Stem Cells

Tithonia diversifolia (Hemsl.) A. Gray (Asteraceae) is widely used in traditional medicine. There is increasing interest on the in vivo protective effects of natural compounds contained in plants against oxidative damage caused from reactive oxygen species. In the present study the total phenolic and flavonoid contents of aqueous, methanol and dichloromethane extracts of leaves of Tithonia diversifolia (Hemsl.) A. Gray were determined; furthermore, free radical scavenging capacity of each extract and the ability of these extracts to inhibit in vitro plasma lipid peroxidation were also evaluated. Since oxidative stress may be involved in trasformation of pre-adipocytes into adipocytes, to test the hypothesis that Tithonia extract may also affect adipocyte differentiation, human mesenchymal stem cell cultures were treated with Tithonia diversifolia aqueous extract and cell viability, free radical levels, Oil-Red O staining and western bolt analysis for heme oxygenase and 5''-adenosine monophoshate-activated protein kinase were carried out. Results obtained in the present study provide evidence that Tithonia diversifolia (Hemsl.) A. Gray exhibits interesting health promoting properties, resulting both from its free radical scavenger capacity and also by induction of protective cellular systems involved in cellular stress defenses and in adipogenesis of mesenchymal cells.     

Expression of Treg Subsets on Intestinal T Cell Immunity and Endotoxin Translocation in Porcine Sepsis After Severe Burns

In the present study, the changes of the regulatory T cells (Treg) expression, endotoxin translocation, and the relationships in intestinal lymph nodes were investigated in porcine sepsis induced by severe burns. Flow cytometry, western blot, and Tachypleus amebocyte lysate were applied to study after the burn injury model was built. We found that the upregulated Treg expression was negatively related to the CD3⁺CD4⁺/CD3⁺CD8⁺ ratio (r = ?0.832, P < 0.05) after burn injury-induced sepsis. While Treg expression and portal venous plasma endotoxin translocation levels were positively correlated (r = 0.876, P < 0.05) when compared with the control group. Moreover, we detected a transforming of T cell subsets from T helper 1 cells to T helper 2 cells. Therefore, intestinal Treg cells expression exerts immunosuppressive effects on other intestinal T lymphocytes and was closely related to endotoxin translocation in porcine sepsis after severe burns injuries. Above all, the intestinal Treg cells may play an important role in the intestinal immune barrier system after severe burns injuries.     

Pre-release evaluation of absolute spillover impact risk of Physonota maculiventris (Chrysomelidae: Cassidinae) on non-target plant species Helianthus annuus (Asteraceae) and Zea mays (Poaceae) in South Africa

The tortoise beetle, Physonota maculiventris (Coleoptera: Chrysomelidae), a candidate biological control agent of Tithonia diversifolia (Hemsl.) A. Gray (Asteraceae) was screened for spillover risks on non-target plant species in South Africa. Studies were conducted to measure the absolute feeding damage and reproductive performance of P. maculiventris on non-target plant species, Helianthus annuus L. (Asteraceae) and Zea mays L. (Poaceae). The influence of spillover on generational build-up performance on the non-target plant species was also investigated. Adult female beetles were switched from T. diversifolia at 14 (actively feeding colony) or 24 (gravid colony) days to the non-target species. Likewise, as a backup or control, female beetles were exposed to H. annuus in a no-choice situation and switched to T. diversifolia and Z. mays. Feeding damage, adult longevity and egg production of P. maculiventris were significantly lower on H. annuus, compared to those metrics on T. diversifolia. Gravid P. maculiventris adults switched from T. diversifolia on the 14th day after emergence laid a few egg batches on the leaf surfaces of Z. mays, but no signs of feeding were observed. Furthermore, the population of P. maculiventris significantly increased by 11.7 fold (26.8–312.5 adults) between the first (F1) and second (F2) generations on T. diversifolia, while on the non-target, H. annuus, it decreased from 6.3 to zero (0). The study concludes that P. maculiventris will sustain its populations entirely on the target, T. diversifolia population stands associated with or without H. annuus and Z. mays cultivations at different scales in South Africa.     

The Usefulness of Non-Toxic Plant Metabolites in the Control of Bacterial Proliferation

The effect of generally recognised as safe (GRAS) plant metabolites in regulating the growth of human pathogenic and probiotic bacteria and in the formation of biofilm was investigated. Thymol, carvacrol and eugenol showed the strongest antibacterial action against both pathogenic and probiotic microorganisms, at a subinhibitory concentration (SIC) of ≤50 μg ml^?1. Genistein, hydroquinone, p-hydroxybenzoic acid and resveratrol also showed antibacterial effects but at a wide concentration range (SIC = 50–1000 μg ml^?1). Catechin, gallic acid, protocatechuic acid and cranberry extracts were the most biologically compatible molecules (SIC ≥ 1000 μg ml^?1). Regarding the effect on biofilm, it was observed that thymol, carvacrol and eugenol showed antibiofilm activity against all potential pathogenic bacteria tested whilst specifically enhancing probiotic aggregation. Catechin, genistein and cranberry extracts did not inhibit the pathogenic aggregation but they stimulated probiotic biofilm formation, whilst gallic acid, protocateuchic acid, hydroquinone, p-hydroxybenzoic acid and resveratrol did not show opposite effect on biofilm formation between pathogenic and probiotic microorganisms. These results indicate that an appropriate combination of GRAS plant metabolites, which have traditionally been used as dietary constituents due to their health-promoting characteristics, can also be extremely useful in the regulation of bacterial proliferation in the intestinal microbiota. Hence, it is suggested to apply these natural GRAS molecules as dietary supplements in the food industry in order to promote probiotic viability and to prevent or reduce colonisation or proliferation of intestinal pathogens.     

Tetrandrine Attenuated Cerebral Ischemia/Reperfusion Injury and Induced Differential Proteomic Changes in a MCAO Mice Model Using 2-D DIGE

Ischemic stroke is the most common type of stroke and brings about a big disease burden because of high mortality and disability in China. Tetrandrine, a bisbenzylisoquinoline alkaloid isolated from the Chinese herb Radix Stephania tetrandra, has been demonstrated to possess anti-inflammatory and free radical scavenging effects and even regulate astrocyte activation, but the possible role of tetrandrine in ameliorating cerebral ischemia/reperfusion injury of ischemic stroke remains unknown. The aim of this study was to determine the effects of tetrandrine on neurological injury and differential proteomic changes induced by transient reversible middle cerebral artery occlusion (MCAO) in mice. Male Balb/c mice were divided into sham (n = 30), MCAO + saline as control (n = 30), and MCAO + Tet as tetrandrine-treated (n = 30) groups. Mice in the control and tetrandrine-treated groups underwent 120 min of MCAO following reperfusion. Immediately and 2 h after MCAO, the mice received either normal saline (sham operated and control groups) or tetrandrine (tetrandrine-treated group) intraperitoneally. Neurological defects, brain water content, and infarct volume at 24 h after stoke were used to evaluate neurological injury extent. Treatment with tetrandrine not only mitigated cerebral neurological deficits (P < 0.05) and infarct size (P < 0.01), but also decreased brian edema in the ischemic brain (P < 0.05). Then, fluorescence two-dimensional difference in gel electrophoresis was used to detect our systematic differential profiling of proteomic changes responding to tetrandrine administration. We validated that the expression of GRP78, DJ-1 and HYOU1 was associated with neuroprotective effect of tetrandrine in MCAO model by Western blotting. These findings indicate a potential neuroprotective role of tetrandrine for ischemic stroke and yield insights into cellular and molecular mechanisms of tetrandrine taking place in ischemic stroke.     

Apelin-13 Inhibits Apoptosis of Cortical Neurons Following Brain Ischemic Reperfusion Injury in a Transient Model of Focal Cerebral Ischemia

Stroke is the third leading cause of death world-wide, affecting 15 million people annually. Diminished blood supply to the brain cells is the main cause of damage following stroke. When focal ischemia occurs, the core of brain tissue influenced by reduced blood supply undergoes necrotic cell death. The adipocytokine Apelin is a peptide that was isolated from a bovine stomach for the first time. This peptide and its receptor are abundantly expressed in the nervous and cardiovascular systems. According to previous studies, Apelin-13 protects cardiomyocytes from ischemic injury and apoptosis. In addition, this peptide has neuroprotective effect on hippocampal and cultured mouse cortical neurons against NMDA receptor-mediated excitotoxicity as well as cortical neurons from ischemic injury. The present study was conducted to determine whether Apelin-13 inhibits apoptosis in the ischemic penumbra in transient focal cerebral ischemia. Focal cerebral ischemia was induced in male Wistar rats by 60 min middle cerebral artery occlusion (MCAO) using a filament method, followed by 23-h reperfusion. Saline as a vehicle and Apelin-13 at doses of 50 and 100 μg were injected intracerebro-ventriculary (ICV) at the beginning of ischemia. Apoptosis and neurological dysfunction were assessed 24-h after MCAO. Our results indicated that administration of Apelin-13 at doses of 50 and 100 μg ICV markedly reduced apoptosis by decreasing positive TUNEL cells (P < 0.001). In addition, Apelin-13 at doses of 100 μg significantly change neurological dysfunction (P < 0.05). Our findings demonstrate that treatment by Apelin-13 exerts its protective effects in ischemic models via blocking programmed cell-death. We suggest that Apelin-13 might be a promising therapeutic target for stroke, although more researches are necessary to take into account the potential therapeutic effects of Apelin-13 in stroke patients.     

Analysis of Risk Factors of Hemorrhagic Transformation After Acute Ischemic Stroke: Cerebral Microbleeds Do Not Correlate with Hemorrhagic Transformation

To study the potential risk factors including cerebral microbleeds (CMB) of hemorrhagic transformation (HT) after acute ischemic stroke. We included 348 consecutive patients with acute infarction who were hospitalized in two centers from June 2009 to December 2010. Acute ischemic infarctions were subdivided into atherosclerotic, cardioemblic, lacunar, and undetermined infarction groups. The related risk factors were recruited for analysis. All patients underwent gradient-echo T2-weighted imaging (GRE) to detect CMB and HT. Logistic regression analysis was used to analyze relationships, with HT as response variable and potential risk factors as explanatory variables. Multivariate logistic regression analysis demonstrated that predictor factors of HT were cardioembolic infarction (OR 24.956, 95 % CI 2.734–227.801, P = 0.004), infarction of undetermined causes (OR 19.381, 95 % CI 1.834–205.104, P = 0.014), and scores of NIHSS (OR 1.187, 95 % CI 1.109–1.292, P < 0.001), diabetes mellitus (OR 4.973, 95 % CI 2.004–12.338, P = 0.001). Whereas, the level of low-density lipoprotein was the protective factor (OR 0.654, 95 % CI 0.430–0.996, P = 0.048).The prevalence of CMB was 45.98 % (160/348) with no statistically difference among different subtypes. Thirty-five out of 348 (10.06 %) patients with ischemic stroke developed HT with a statistical difference among different subtypes of ischemia (χ ² = 42.140, P < 0.001). The distributions of HI and PH among subgroups were variable with significant differences (χ ² = 17.536, P = 0.001; χ ² = 12.028, P = 0.007). PH frequency of cardioembolism was the highest (4/28, 14.29 %), and symptomatic ICH was also highest (7.14 %). The CMBs do not significantly correlate with HT. Knowledge of the risk factors associated with HT after ACI, especially HT following thrombolyitc therapy may provide insight into the mechanisms underlying the development of HT, helps to develop treatment strategy that reduces the risk of PH and implicates for the design of future acute ischemic stroke trials.     

BRG1 variant rs1122608 on chromosome 19p13.2 confers protection against stroke and regulates expression of pre-mRNA-splicing factor SFRS3

A single nucleotide polymorphism (SNP) rs1122608 on chromosome 19p13.2 and in the BRG1/SMARCA4 gene was previously associated with coronary artery disease (CAD). CAD and ischemic stroke are both associated with atherosclerosis. Thus, we tested the hypothesis that rs1122608 is associated with ischemic stroke. Further studies were used to identify the most likely mechanism by which rs1122608 regulates atherosclerosis. For case–control association studies, two independent Chinese Han GeneID cohorts were used, including a Central cohort with 1,075 cases and 2,685 controls and the Northern cohort with 1,208 cases and 824 controls. eQTL and real-time RT-PCR analyses were used to identify the potential candidate gene(s) affected by rs1122608. The minor allele T of SNP rs1122608 showed significant association with a decreased risk of ischemic stroke in the Central GeneID cohort (adjusted P _adj = 2.1 × 10^?4, OR 0.61). The association was replicated in an independent Northern GeneID cohort (P _adj = 6.00 × 10^?3, OR 0.69). The association became more significant in the combined population (P _adj = 7.86 × 10^?5, OR 0.73). Allele T of SNP rs1122608 also showed significant association with a decreased total cholesterol level (P _adj = 0.013). Allele T of rs1122608 was associated with an increased expression level of SFRS3 encoding an mRNA splicing regulator, but not with the expression of BRG1/SMARCA4 or LDLR (located 36 kb from rs1122608). Increased expression of SFSR3 may decrease IL-1β expression and secretion, resulting in reduced risk of atherosclerosis and stroke. This is the first study that demonstrates that rs1122608 confers protection against ischemic stroke and implicates splicing factor SFSR3 in the disease process.     

Antioxidant activity of brown alga Saccharina bongardiana from Kamchatka (Pacific coast of Russia). A methodological approach

The present study aims to investigate the levels of polyphenols and antioxidant activity in one of the most important commercial species of seaweeds in Kamchatka, an edible brown seaweed Saccharina bongardiana. Six extracts of S. bongardiana, acetone, methanol, ethanol, and the respective 70 % aqueous solutions, were assessed for total phenol content in order to determine the most efficient extracting solvent. The total phenol content was measured by the Folin–Ciocalteu method and expressed as phloroglucinol equivalents (PGE). The antioxidant tests used were 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, linoleic acid-β carotene oxidation inhibiting assay, and Fe²⁺ ion chelating method. Higher phenolic contents were obtained using aqueous organic solvents, as compared to the respective absolute solvents; 70 % acetone was found to be the most efficient solvent (1.039 mg PGE 100 mg^?1 dry algal powder). High significant correlations were noted between total phenol content and the tested antioxidant activities; so the aqueous organic extracts exhibited the highest antioxidant activities versus DPPH radicals (EC₅₀ values of 0.6–1.1 mg dry weight (DW) mL^?1), linoleic acid-β carotene oxidation (74–78 % at 0.8 mg DW mL^?1), as well as ferrous ions (EC₅₀ values of 5.0–7.9 mg DW mL^?1). Some methodological recommendations regarding the assays used and the expression of results are proposed.     

Induction of laccases in Trametes versicolor by aqueous wood extracts

The induction of laccase isoforms in Trametes versicolor HEMIM-9 by aqueous extracts (AE) from softwood and hardwood was studied. Samples of sawdust of Pinus sp., Cedrela sp., and Quercus sp. were boiled in water to obtain AE. Different volumes of each AE were added to fungal cultures to determine the amount of AE needed for the induction experiments. Laccase activity was assayed every 24 h for 15 days. The addition of each AE (50 to 150 μl) to the fungal cultures increased laccase production compared to the control (0.42 ± 0.01 U ml^?1). The highest laccase activities detected were 1.92 ± 0.15 U ml^?1 (pine), 1.87 ± 0.26 U ml^?1 (cedar), and 1.56 ± 0.34 U ml^?1 (oak); laccase productivities were also significantly increased. Larger volumes of any AE inhibited mycelial growth. Electrophoretic analysis revealed two laccase bands (lcc1 and lcc2) for all the treatments. However, when lcc2 was analyzed by isoelectric focusing, inducer-dependent isoform patterns composed of three (pine AE), four (oak AE), and six laccase bands (cedar AE) were observed. Thus, AE from softwood and hardwood had induction effects in T. versicolor HEMIM-9, as indicated by the increase in laccase activity and different isoform patterns. All of the enzymatic extracts were able to decolorize the dye Orange II. Dye decolorization was mainly influenced by pH. The optimum pH for decolorization was pH 5 (85 %), followed by pH 7 (50 %) and pH 3 (15 %). No significant differences in the dye decolorizing capacity were detected between the control and the differentially induced laccase extracts (oak, pine and cedar). This could be due to the catalytic activities of isoforms with pI 5.4 and 5.8, which were detected under all induction conditions.     

Propofol Increases Expression of Basic Fibroblast Growth Factor After Transient Cerebral Ischemia in Rats

Anesthetics such as propofol can provide neuroprotective effects against cerebral ischemia. However, the underlying mechanism of this beneficial effect is not clear. Therefore, we subjected male Sprague–Dawley rats to 2 h of middle cerebral artery occlusion and investigated how post-ischemic administration of propofol affected neurologic outcome and the expression of basic fibroblast growth factor (bFGF). After 2 h of ischemia, just before reperfusion, the animals were randomly assigned to receive either propofol (20 mg kg^?1 h^?1) or vehicle (10 % intralipid, 2 ml kg^?1 h^?1) intravenously for 4 h. Neurologic scores, infarct volume, and brain water content were measured at different time points after reperfusion. mRNA level of bFGF was measured by real-time PCR, and the protein expression level of bFGF was analyzed by immunohistochemistry and Western blot. At 6, 24, 72 h, and 7 days of reperfusion, infarct volume was significantly reduced in the propofol-treated group compared to that in the vehicle-treated group (all P < 0.05). Propofol post-treatment also attenuated brain water content at 24 and 72 h and reduced neurologic deficit score at 72 h and 7 days of reperfusion (all P < 0.05). Additionally, in the peri-infarct area, bFGF mRNA and protein expression were elevated at 6, 24, and 72 h of reperfusion compared to that in the vehicle-treated group (all P < 0.05). These results show that post-ischemic administration of propofol provides neural protection from cerebral ischemia–reperfusion injury. This protection may be related to an early increase in the expression of bFGF.     

Evaluation of cytological and genetic effects of Tribulus terrestris fruit aqueous extract on cultured human lymphocytes

The current study was carried out to evaluate the genotoxic aspects of the aqueous extracts of the Tribulus terrestris fruits by comet assay and cytogenetic procedures conditions on cultured human peripheral blood lymphocyte. After the treatment of the lymphocytes with four concentrations of the aqueous fruit extract of T. terrestris (10, 20, 40 and 80 mg/L) for 24 h it was noticed that, the presence of micronuclei and/or chromosomal aberration were monitored and a significant increase of comet cells at high concentration of T. terrestris extract 80 mg/L. Also, this study showed that the presence of micronuclei, chromosomal aberration as a chromosomal gap, fragmentation, stickiness and necrotic cells were appeared and increased with high concentrations of T. terrestris fruits extract (40–80 mg/L). On the other hand, no significant difference was observed with the low concentration of the extract (10–20 mg/L) as compared with control. The current study refers to the ability of the extract of T. terrestris fruits to do damage in the target DNA at the higher concentrations. Thus, it could be considered that the aqueous extracts of the T. terrestris fruits have genotoxic effect in the therapeutic protocols if it used in high doses.     

Genotoxicity of Thermopsis turcica on Allium cepa L. roots revealed by alkaline comet and random amplified polymorphic DNA assays

This study was undertaken to evaluate genotoxic potential of Thermopsis turcica aqueous extracts on the roots of onion bulb (Allium cepa L.) by comet assay and random amplified polymorphic DNA technique. The Allium root growth inhibition test indicated that the EC₅₀ and 2×EC₅₀ values were 8 and 16 mg/ml concentrations of T. turcica aqueous extracts, respectively. The negative control (distilled water), positive control (methyl methane sulfonate, 10 mg/l) and 8 and 16 mg/ml concentrations of T. turcica extracts were introduced to the roots of onion bulbs for 24 and 96 h. The root growth, DNA damage in root cells and randomly amplified polymorphic DNA (RAPD) profiles of root tissue were used as endpoints of the genotoxicity. The comet assay clearly indicated that dose-dependent single strand DNA breaks in the root nuclei of onions were determined for the treatment concentrations of T. turcica extracts. In comparison to RAPD profile of negative control group, RAPD polymorphisms became evident as disappearance and/or appearance of RAPD bands in treated roots. The diagnostic and phenetic numerical analyses of RAPD profiles obviously indicated dose-dependent genotoxicity induced by Thermopsis extracts. In conclusion, the results clearly indicated that water extract of T. turcica has genotoxic potential on the roots of onion bulbs as shown by comet assay and RAPD technique.     

Phythonematoxic properties and nematicidal potential of Tithonia diversifolia extract and residue on Meloidogyne incognita infecting yam (Discoria rotundata)

A laboratory study and a screen house experiment were conducted to determine the phythonematoxic properties and nematicidal potential of extract and residue of Tithonia diversifolia (Hemsl.) A. Gray on Meloidogyne incognita, (Kofoid and White) Chitwood infecting yam. Alkaloids and saponins were found to be present in the constituents of Tithonia ethanol extract. Also, Tithonia water extract significantly (P ≤ 0.05) inhibits M. incognita egg hatch by 98% from 2 days after incubation (DAI) and was more evidenced with 100% inhibition at 9 DAI in the in vitro studies. M. incognita (5000 eggs/plant) reproduction, number of eggs and juveniles and galling were significantly (P ≤ 0.05) suppressed by Tithonia residue treatment at a rate of 30 tons/ha on yam (Discoria rotundata) in the screen house. The extract and residue of T. diversifolia have potential for the control of root-knot nematodes.     

Reversible Loss of N-Acetylaspartate After 15-Min Transient Middle Cerebral Artery Occlusion in Rat: A Longitudinal Study with In Vivo Proton Magnetic Resonance Spectroscopy

It is generally accepted that N-acetylaspartate (NAA) can be used a biochemical marker for assessing neuronal viability/integrity after cerebral ischemia. However, this view has recently been questioned based on observations showing that after a photothrombotic permanent ischemia the acute decline of NAA in the infracted regions, where massive neuronal loss persists, is reversible over time. In this study, we measured the longitudinal changes of NAA and total creatine (Cr) in ischemic rat brain after a 15-min transient middle cerebral artery occlusion (MCAO) by in vivo ¹H magnetic resonance spectroscopy. The results showed that the levels of NAA and total Cr in the ischemic lesion decrease significantly at 1 day post-ichemia, followed by spontaneous recovery to the control levels by 2 weeks and remained stable thereafter up to 16 weeks. The normalization of NAA and total Cr levels was associated histologically with persisted neuronal loss up to 90 % in the ischemic core, and accompanied by marked reactive astrocytic responses occurring with a similar time course. The absolute T₂ relaxation time in the ischemic lesion increased during acute phase, and declined afterwards during subacute and chronic phases of 15-min MCAO. The delayed decreases of T₂ in the ischemic lesion might be associated with deposition of paramagnetic species, such as manganese and iron originated from chronic inflammation, vascular degradation and/or hemorrhagic transformation. The results of this study give further support to the hypothesis that the recovery of NAA after cerebral ischemia might have contributions from reactive glia cells, and caution the use of NAA as a specific neuronal marker during the chronic stage of cerebral ischemia.     

Intranasal guanosine administration presents a wide therapeutic time window to reduce brain damage induced by permanent ischemia in rats

In addition to its intracellular roles, the nucleoside guanosine (GUO) also has extracellular effects that identify it as a putative neuromodulator signaling molecule in the central nervous system. Indeed, GUO can modulate glutamatergic neurotransmission, and it can promote neuroprotective effects in animal models involving glutamate neurotoxicity, which is the case in brain ischemia. In the present study, we aimed to investigate a new in vivo GUO administration route (intranasal, IN) to determine putative improvement of GUO neuroprotective effects against an experimental model of permanent focal cerebral ischemia. Initially, we demonstrated that IN [³H] GUO administration reached the brain in a dose-dependent and saturable pattern in as few as 5 min, presenting a higher cerebrospinal GUO level compared with systemic administration. IN GUO treatment started immediately or even 3 h after ischemia onset prevented behavior impairment. The behavior recovery was not correlated to decreased brain infarct volume, but it was correlated to reduced mitochondrial dysfunction in the penumbra area. Therefore, we showed that the IN route is an efficient way to promptly deliver GUO to the CNS and that IN GUO treatment prevented behavioral and brain impairment caused by ischemia in a therapeutically wide time window.     

Autophagy Activation Contributes to the Neuroprotection of Remote Ischemic Perconditioning Against Focal Cerebral Ischemia in Rats

Remote ischemic perconditioning (RIPer) has been proved to provide potent cardioprotection. However, there are few studies on neuroprotection of RIPer. This study aims to clarify the neuroprotective effect of RIPer and the role of autophagy induced by RIPer against cerebral ischemia reperfusion injury in rats. Using a transient middle cerebral artery occlusion (MCAO) model in rats to imitate focal cerebral ischemia. RIPer was carried out 4 cycles of 10 min ischemia and 10 min reperfusion, with a thin elastic band tourniquet encircled on the bilateral femoral arteries at the start of 10 min after MCAO. Autophagy inhibitor 3-methyladenine (3-MA) and autophagy inducer rapamycin were administered respectively to determine the contribution of autophagy in RIPer. Neurologic deficit scores, infarct volume, brain edema, Nissl staining, TUNEL assay, immunohistochemistry and western blot was performed to analyze the neuroprotection of RIPer and the contribution of autophagy in RIPer. RIPer significantly exerted neuroprotective effects against cerebral ischemia reperfusion injury in rats, and the autophagy-lysosome pathway was activated by RIPer treatment. 3-MA reversed the neuroprotective effects induced by RIPer, whereas rapamycin ameliorated the brain ischemic injury. Autophagy activation contributes to the neuroprotection by RIPer against focal cerebral ischemia in rats.     

Accumulation of hydroxybenzoic acids and other biologically active phenolic acids in shoot and callus cultures of Aronia melanocarpa (Michx.) Elliott (black chokeberry)

Phenolic acids are plant metabolites important in phytotherapy and also in cosmetology. In this study, proliferating shoot and callus cultures of Aronia melanocarpa were established and maintained on Linsmaier and Skoog (L-S) medium containing different levels of α-naphthaleneacetic acid (NAA) and 6-benzyladenine (BA), ranging from 0.1 to 3.0 mg l^?1. Methanolic extracts from the biomass of these cultures and from the fruits of soil-grown plants were used to determine the amounts of free phenolic acids and cinnamic acid using the high-performance liquid chromatography (HPLC) method. Out of a total of twelve analyzed compounds, all of the extracts contained four of them: caffeic acid, p-hydroxybenzoic acid, syringic acid, and vanillic acid. Moreover, shoot extracts also contained salicylic acid (o-hydroxybenzoic acid), while callus extracts contained p-coumaric acid. On the other hand, fruit extracts also contained both salicylic acid and p-coumaric acid. The total amount of the analyzed compounds in extracts from both shoot and callus cultures depended on the L-S medium used, and varied between 103.05 and 150.95 mg 100 g^?1 dry weight (DW), and between 50.23 and 81.56 mg 100 g^?1 DW, respectively. Both types of culture contained higher levels of phenolic acids than the fruit extracts (32.43 mg 100 g^?1 DW). In shoot cultures, p-hydroxybenzoic acid and salicylic acid were the predominant metabolites (reaching 55.14 and 78.25 mg 100 g^?1 DW, respectively), while in callus cultures, p-hydroxybenzoic acid (25.60 mg 100 g^?1 DW) and syringic acid (41.20 mg 100 g^?1 DW) were the main compounds. In fruit extracts, salicylic acid (15.60 mg 100 g^?1 DW) and p-hydroxybenzoic acid (5.29 mg 100 g^?1 DW) were predominant.