Life Span Of Group Research Articles

Synergistic Neuroprotective Effects of a Natural Product Mixture against AD Hallmarks and Cognitive Decline in Caenorhabditis elegans and an SAMP8 Mice Model

The study of different natural products can provide a wealth of bioactive compounds, and more interestingly, their combination can exert a new strategy for several neurodegenerative diseases with major public health importance, such as Alzheimer’s disease (AD). Here, we investigated the synergistic neuroprotective effects of a mixed extract composed of docosahexaenoic acid, Ginkgo biloba, D-pinitol, and ursolic acid in several transgenic Caenorhabditis elegans (C. elegans) and a senescence-accelerated prone mice 8 (SAMP8) model. First, we found a significantly higher survival percentage in the C. elegans group treated with the natural product mixture compared to the single extract-treated groups. Likewise, we found a significantly increased lifespan in group of C. elegans treated with the natural product mixture compared to the other groups, suggesting synergistic effects. Remarkably, we determined a significant reduction in Aβ plaque accumulation in the group of C. elegans treated with the natural product mixture compared to the other groups, confirming synergy. Finally, we demonstrated better cognitive performance in the group treated with the natural product mixture in both AD models (neuronal Aβ C. elegans strain CL2355 and the SAMP8 mice model), confirming the molecular results and unraveling the synergist effects of this combination. Therefore, our results proved the potential of this new natural product mixture for AD therapeutic strategies.

Establishment of calcium oxalate calculus model in drosophila induced by ethylene glycol

Objective There is not any report on the Drosophila model of calcium oxalate calculus in China yet. We performed this study to develop a Drosophila model of calcium oxalate calculus, and to evaluate the stability and applicability of the model. Methods 400 same days old male Drosophila melanogaster were randomly divided into four groups: group A (n1=100), group B (n2=100), group C (n3=100) and group D (n4=100). After carbon dioxide anesthesia, they were transferred into conical flask with medium with 0.50%, 0.75%, 1.0% ethylene glycol and normal culture medium respectively. Drosophila were raised in 25 ℃ incubator, and their life span was recorded. After dissection of the Malpighi tubule, the crystal formation of the Drosophila was observed. Then the crystals were obtained and analyzed. Results The crystallization rates of groups A, B, C and D were 87%, 92%, 98% and 6%, respectively (χ2=273.057, P=0.000). The median life span of group A, B, C, D was 36 days, 31 days, 23 days and 52 days respectively, one-way ANOVA showed that F=35.403 and P=0.000. The crystals consisted of calcium oxalate. Conclusion 0.75% of the ethylene glycol concentration is considered to be the ideal concentration due to its high rate of stone formation, the relatively low mortality. In addition, The model is suitable for large sample volume drug test which make big sense for urolithiasis study. Key words: Urolithiasis; Drosophila melanogaster; Malpighi tubule; Ethylene glycol; Model, animal

Interactions between the developmental and adult social environments mediate group dynamics and offspring traits in Drosophila melanogaster

Developmental conditions can strongly influence adult phenotypes and social interactions, which in turn affect key evolutionary processes such as sexual selection and sexual conflict. While the implications of social interactions in phenotypically mixed populations at the individual level are increasingly well known, how these effects influence the fate of groups remains poorly understood, which limits our understanding of the broader ecological implications. To address this problem we manipulated adult phenotypes and social composition in Drosophila melanogaster – by experimentally manipulating the larval density of the group-members – and measured a range of group-level outcomes across the lifespan of groups. Adult groups composed of exclusively low larval-density individuals showed high courtship levels, and low early reproductive rates, group growth rates, offspring mass and offspring eclosion success, relative to high larval-density or mixed larval-density groups. Furthermore, high larval-density groups had lower survival. Offspring mass increased with time, but at a reduced rate in groups when male group members (but not females) were from a mixture of larval-densities; peak reproductive rates were also earlier in these groups. Our results suggest that that variation in developmental conditions experienced by adult group members can modify the reproductive output of groups.

Minocycline increases the life span and motor activity and decreases lipid peroxidation in manganese treated Drosophila melanogaster

The objective of this study was to investigate the effect of Minocycline in the life span, motor activity, and lipid peroxidation of Drosophila melanogaster treated with manganese. Two days after emerging from the pupa male wild-type D. melanogaster were fed for 13 days with corn media containing 15mM manganese. Then, they were divided in six groups of 300 flies each: group (a) remained treated with manganese (Mn group); group (b) began treatment with Minocycline (0.05mM) (Mn−Minocycline group); group (c) received no additional treatment (Mn-no treatment group); group (d) simultaneously fed with manganese and Minocycline (Mn+Minocycline group). Additionally, a control (group e) with no treatment and another group (f) fed only with Minocycline after emerging from the pupa were added. All the manganese treated flies (group a) were dead on the 25th day. The life span in group f (101.66±1.33 days, mean S.E.M.) and of group b (97.00±3.46 days) were similar, but in both cases it was significantly higher than in group e (68.33±1.76 days), group c (67.05±2.30 days) and in those of group d (37.33±0.88). Manganese (groups a and d) decreased motor activity in D. melanogaster. In the Minocycline fed flies (groups b and f) a higher motor activity was detected. In Mn−Minocycline and Mn+Minocycline treated flies a significant decrease of MDA levels was detected when compared to the Minocycline group indicating that Minocycline and Mn appear to have a synergistic effect. In conclusion, Minocycline increased the life span and motor activity and decreased MDA formation of manganese treated D. melanogaster, probably by an inhibition of the production of reactive oxygen species. Manganese also exerted an antioxidant effect as shown by the significant decrease of MDA levels when compared to control flies.

Lower value of glycated haemoglobin relative to glycaemic control in diabetic patients with end-stage renal disease not on haemodialysis

Glycated haemoglobin (HbA1c) concentration is lower relative to glyacemic control in diabetic patients on haemodialysis. However, it is unknown as to whether this is also true for diabetic patients with end-stage renal disease but not on haemodialysis. Correlations between HbA1c or glycated albumin (GA) and estimated glomerular filtration rate (eGFR) (determined by serum creatinine concentration, sex and age) were investigated in 86 diabetic patients with renal dysfunction not on dialysis. The mean values of HbA1c and of red blood cell (RBC) lifespan were compared among four groups of patients: Group 1 (n = 30, eGFR ≥ 60 mL/min/1.73 m(2)), Group 2 (n = 30, eGFR < 60 mL/min/1.73 m(2) but ≥30 mL/min/1.73 m(2)), Group 3 (n = 13, eGFR < 30 mL/min/1.73 m(2) but ≥15 mL/min/1.73 m(2)) and Group 4 (n = 13, eGFR < 15 mL/min/1.73 m(2) without haemodialysis). RBC lifespan was determined in each subject from the difference between alveolar carbon monoxide (CO) concentration and atmospheric CO concentration. HbA1c was significantly correlated with eGFR (r = 0.37, P = 0.0004), but GA was not. The HbA1c values in Group 3 (6.8 ± 0.6%) and Group 4 (6.3 ± 0.5%) were significantly lower than that in Group 1 (7.4 ± 0.8%), but there was no difference between Group 2 (7.2 ± 0.7%) and Group 1. There was a significant correlation between RBC lifespan and eGFR, and the mean RBC lifespan in Group 3 (96 ± 35 d) and Group 4 (94 ± 30 d) were significantly shorter than that in Group 1 (127 ± 30 d). Diabetic patients with stage 4 or 5 chronic kidney disease not on haemodialysis had significantly lower values of HbA1c and shorter RBC lifespan compared with diabetic patients without renal dysfunction.

Abstract 5243: Value of 1H magnetic resonance spectroscopy compared with anatomical imaging in predicting response to standard chemotherapy and radiation in U87-MG-luc intracranial glioma model

Abstract Introduction: Luciferase enabled tumor cell lines are widely used for tracking orthotopic tumor burden in small animal models using bioluminescence imaging (BLI). Tumor burden estimated by MRI, while clinically relevant, may not correlate with patient survival. Tumor total (or phospho) choline has been shown to be an early indicator of tumor response to therapy measured using 1H (or 31P) magnetic resonance spectroscopy (MRS). In this study, correlation of response to therapy as measured by total choline (using 1H MRS) was compared with luciferase and MRI assessments of tumor burden, and lifespan. Materials and methods: U87-MG-luc human glioma cells (106 cells in 10 μl) were implanted using a stereotax frame intracranially (2mm right lateral and 1mm anterior to the coronal suture at a depth of 2mm) in female CD1 nu/nu mice. On Day 27 post implant, intracranial tumor burden was characterized using BLI and animals were randomized into 3 groups-Group 1(n=9): vehicle controls saline, QDx5, 0.2ml/20g; Group 2 (n=9): BCNU QDx5, IV, 15mg/kg; Group 3 (n=6): 15 Gy radiation; (QDx5;2off)x2wks). Pre-treatment and 1 week post treatment scans were acquired using BLI (tumor burden), T2 weighted MRI (tumor volume) and water suppressed proton MR spectroscopy (spectra fitted to obtain total choline/NAA ratio). Additional BLI scans were performed weekly and animal lifespan was also recorded. For each parameter, mean and median were analyzed. Additionally, to assess the predictive power of each parameter, the animals on study were distributed into responder or non-responder categories using median lifespan in the control group as the threshold for response determination. Mean and medians for each parameter were then calculated separately for responders and non-responders. Discussion: A Mann-Whitney rank sum test showed that the difference in median survival in both the treated groups was significantly different from controls, which had a median lifespan of 37.5 days. BCNU treatment (Group 2, p=0.021) was moderately active, resulting in a 5.5 day improvement in median lifespan. Radiation treatment (Group 3, p=0.003) was highly active, resulting in an 18.5 day improvement in median lifespan. Anatomical MRI determined tumor volumes and tumor luciferase signals at 1 week post treatment start were predictive of group median lifespan in Groups 2 and 3. Cho/NAA ratio at 1 week post-treatment start also correlated with response for Groups 2 and 3, but was less sensitive than the anatomically derived parameters. The secondary analysis based on response category revealed results consistent with the group mean and median analyses for all 3 parameters. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5243.

Nucleotide sequence diversity of the 5S rDNA spacer in the simple blade kelp genera Laminaria, Cymathaere and Kjellmaniella (Laminariales, Phaeophyceae) from northern Japan

SUMMARYTandem repeats of the 5S ribosomal RNA gene (rDNA) were confirmed for almost all laminarian, cymathaerean and kjellmaniellan species distributed in northern Japan. The nucleotide sequence of the spacer region between tandemly repeated 5S rDNA was investigated for 79 samples from 31 sites. Phylogenetic analysis of the 29 different sequences detected revealed two lineages: (1) Laminaria coriacea group, including Laminaria coriacea Miyabe, Laminaria cichorioides Miyabe, Laminaria sachalinensis (Miyabe) Miyabe, Laminaria yendoana Miyabe, Cymathaere japonica Miyabe et Nagai, Kjellmaniella gyrata (Kjellman) Miyabe and Kjellmaniella crassifolia Miyabe; (2) Laminaria japonica group including Laminaria japonica Areschoug, Laminaria religiosa Miyabe, Laminaria ochotensis Miyabe, Laminaria diabolica Miyabe, Laminaria longipedalis Okamura, Laminaria angustata Kjellman and Laminaria longissima Miyabe. In addition, the latter group was divided into two: subgroup (2a) including L. angustata and L. longissima and subgroup (2b) including L. japonica, L. religiosa, L. ochotensis, L. diabolica and L. longipedalis. Members of the three groups differ from each other in the appearance of ornaments (bullation, gyration and folds) on the surface of the blade. These are absent in group (2a), only present in the early stages of the lifespan of group (2b), and present for the duration of the lifespan in group (1). Genetic distances among samples were extremely small within group (2a). Together with previous crossing studies and data on ocean currents and distribution, these findings suggest that gene flow occurs within group (2b).

Geroprotector effectiveness of melatonin: investigation of lifespan of Drosophila melanogaster

The lifespan (LS) of Drosophila melanogaster was studied under the effect of melatonin at a concentration of 0.08% selected in preliminary experiments. The compound was introduced into a culture medium only at the stage of development. An inverse relationship was observed between the change in LS after the impact of the preparation and the value of LS in the corresponding control group (Spearman's rank correlation coefficient R=−0.83, P<0.02). For a relatively low LS in a population from which the control and experimental groups were formed, the geroprotector effect of melatonin is the most distinct; for a relatively high LS, the effect of the hormone is either not detected or appears as a toxic reduction in LS (up to 10%) in the experimental group. Such nonuniform effects of melatonin are connected with fluctuating changes in viability in successive generations of D. melanogaster. The antioxidant mechanism of the geroprotector effect is also discussed.

Liver and Forestomach Tumors and Other Forestomach Lesions in Rats Treated With Morpholine and Sodium Nitrite, With and Without Sodium Ascorbate&lt;xref ref-type="fn" rid="FN2"&gt;2&lt;/xref&gt;&lt;xref ref-type="fn" rid="FN3"&gt;3&lt;/xref&gt;

Administration to rats of ascorbate with morpholine and nitrite was previously shown to inhibit the liver tumor production and to enhance the induction of forestomach tumors, as compared to treatment with morpholine and nitrite. In a repetition of this experiment, 10 g morpholine/kg in the diet and 2 g sodium nitrite/liter in the drinking water were administered for life to male MRC-Wistar rats without (group 1) or with (group 2) 22.7 g sodium ascorbate/kg in the diet. Group 3 was untreated. Group 2 showed a lower liver tumor incidence with a longer latency than group 1, indicating a 78% inhibition by ascorbate of in vivo N-nitrosomorpholine (NMOR) formation. The incidence of forestomach papillomas was 3% in group 1, 38% in group 2, and 8% in group 3. The difference between groups 1 and 2 was not significant due to the shorter life-span of group 1. Group 1 and especially group 2 had more forestomach hyperplasia and hyperkeratosis than group 3. Ascorbate might have enhanced induction of these lesions because of an action synergistic with that of NMOR. However, it is most likely that the lowered NMOR dose and concomitantly increased survival produced by the ascorbate were solely responsible for the increased incidence of forestomach papillomas and other lesions in group 2.