Impact of preconditioning stem cells with all-trans retinoic acid signaling pathway on cisplatin-induced nephrotoxicity by down-regulation of TGFβ1, IL-6, and caspase-3 and up-regulation of HIF1α and VEGF

The survival reduction after transplantation limited the clinical uses of stem cells so the current study explored preconditioning adipose-derived stem cells (ADMSCs) and all-trans retinoic acid (ATRA) effects on cisplatin that caused acute kidney injury (AKI). One hundred and fifty Sprague–Dawley male rats were distributed into five groups: control group; Cisplatin (CIS) group; CIS and ATRA group; CIS and ADMSC group, and CIS, ATRA, and ADMSCs group. Ten rats were euthanized after 3rd, 7th, and 11th days from CIS injection. Renal function, molecular studies, and histopathological analysis were studied. The preconditioning of ADMSCs with ATRA increased the viability of the cells which was reflected in the amelioration of kidney functions after CIS injection by the significant reduction of serum creatinine, microalbuminuria, as well as NO, and the significant rise of creatinine clearance, as well as SOD compared to the group of cisplatin. ATRA also supported ADMSCs by a significant down-regulation of caspase-3, il-6 and TGFβ1, and a significant up-regulation of HIF1, VEGF and CD31 compared to group of cisplatin which reversed the cisplatin effect. ATRA increased renoprotective properties of ADMSCs against cisplatin- induced AKI by reducing the apoptosis, inflammation, and stimulating angiogenesis.     

Spatial and temporal expression patterns of chitinase genes in developing zebrafish embryos

Chitinases and chitinase like proteins play an important role in mammalian immunity and functions in early zebrafish development have been suggested. Here we report identification of six zebrafish chitinases and chitinase like proteins (called CHIA.1–6) belonging to the glycoside hydrolase family 18, and determine their spatial and temporal expression at 10 stages of zebrafish development.CHIA.4 is highly maternally expressed and it is expressed 100 fold above any other CHIA gene at zygote through to blastula stage. Later, after the maternal to zygotic transition, CHIA.4 expression decreases to the same level as CHIA.5 and CHIA.6. Subsequently, CHIA.1, CHIA.2, CHIA.3 and CHIA.4, CHIA.5, CHIA.6 each follow distinct paths in terms of expression levels.Until 4 days post fertilization the spatial expression patterns of all six CHIA genes overlap extensively, with expression detected predominantly in vascular, ocular and intestinal tissues. At 5 days post fertilization CHIA.1, CHIA.2 and CHIA.3 are expressed almost exclusively in the stomach, whereas CHIA.4, CHIA.5 and CHIA.6 are also prominently expressed in the liver. These different expression patterns may contribute to the establishment of a basis on which functional analysis in older larvae may be founded.     

Effect of streptolysin S on liposomes Influence of membrane lipid composition on toxin action

The effect of the bacterial cytolytic toxin, streptolysin S, on liposomes composed of various phospholipids was investigated. Large unilamellar vesicles containing [¹⁴C]sucrose were prepared by reverse-phase evaporation, and membrane damage produced by the toxin was measured by following the release of labeled marker. The net charge of the liposomes had little or no effect on their susceptibility to steptolysin S and the toxin was about equally effective on liposomes composed of phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and phosphatidylglycerol. Experiments with liposomes composed of synthetic phospholipids showed that the ability of the toxin to produce membrane damage depended on the degree of unsaturation of the fatty acyl chains. The order of sensitivity was C18 : 2 phosphatidylcholine > C18 : 1 phosphatidylcholine > C18 : 0 phosphatidylcholine = C16 : 0 phosphatidylcholine. Liposomes containing the latter two phospholipids were virtually unaffected by streptolysin S, and experiments with C18 : 0 phosphatidylcholine suggested that toxin activity does not bind to liposomes composed of phospholipids with saturated fatty acyl chains. The inclusion of 40 mol% cholesterol in C16 : 0 phosphatidylcholine and C18 : 0 phosphatidylcholine liposomes made these vesicles sensitive to streptolysin S. Egg phosphatidylcholine liposomes, which were unaffected at 0°C and 4°C became susceptible to the toxin at these temperatures when cholesterol was included. Liposomes composed of C14 : 0 phosphatidylcholine were unaffected by streptolysin S at temperatures below the chain-melting transition temperature (23°C) of this phospholipid, but became increasingly susceptible above this temperature. The results suggest that the fluidity of the phospholipid hydrocarbon chains in the membrane is important in streptolysin S action.     

The immunostimulatory effect of IL-1β in vivo is blocked by antisense peptides complementary to the loop sequence 163-171

Antisense (AS) peptides complementary to the β-bulge surface loop VQGEESNDK (Boraschi loop) of the cytokine interleukin-1β (IL-1β) have been shown to bind IL-1β at the Boraschi loop position, and to inhibit some of the IL-1β-mediated biological effects in vitro. Here we show that primary AS peptide FVITFFSLY inhibits IL-1β-mediated immunostimulation in vivo in a dose-dependent fashion, while inactive on IL-1β-induced inflammation, an effect that takes place independently of the Boraschi loop. To the best of our knowledge, this is the first time that an AS peptide has been used successfully in vivo.     

PHYLOGENETIC ANALYSIS AND GENOME SIZE OF OSTREOCOCCUS TAURI (CHLOROPHYTA, PRASINOPHYCEAE)

Ostreococcus tauri Courties et Chrétiennot-Dinet is the smallest described autotrophic eukaryote dominating the phytoplanktonic assemblage of the marine Mediterranean Thau lagoon (France). Its taxonomic position was partly elucidated from ultrastructure and high-pressure liquid chromatography (HLPC) pigment analysis. The sequence analysis of the 18S rDNA gene of O. tauri measured here is available in EMBL Nucleotide Sequence Database (accession number: Y15814) and allowed to clarify its phylogenetic position. O. tauri belongs to the Prasinophyceae and appears very close to Mantoniella, a typical scaly Prasinophyceae, morphologically very different from the naked and coccoid Ostreococcus. An electrophoretic analysis of O. tauri shows that the nucleus contains 10.20 mbp. This small genome, fragmented into 14 chromosomes ranging in size from 300 to 1500 kbp, confirms the minimalist characteristics of Ostreococcus tauri.     

Immune modulation by interleukin-12 in tumor-bearing mice receiving vitamin D3 treatments to block induction of immunosuppressive granulocyte/macrophage progenitor cells

 Lewis lung carcinoma (LLC-LN7) tumors stimulate myelopoiesis and increase the presence of granulocyte/macrophage (GM) progenitor cells having natural suppressor activity. Treatment of these tumor-bearing mice with interleukin-12 (IL-12) resulted in minimal immune modulation. The objective of this study was to determine whether eliminating natural suppressor activity would allow for immune stimulation by IL-12. Treatment of LLC-LN7 tumor-bearing mice with vitamin D₃ eliminated natural suppressor activity. In mice that were first treated with vitamin D₃ and then also with IL-12, there was stimulation of splenic T cell proliferation in response to immobilized anti-CD3 plus IL-2. In addition, spleen and lymph node cells from vitamin-D₃/IL-12-treated tumor-bearing mice became stimulated in response to autologous tumor to produce interferon γ (IFNγ), although IL-2 production was not stimulated. A prominent effect of the combined vitamin-D₃/IL-12 treatment regimen was the synergistic augmentation of autologous tumor-specific cytolytic activity within the regional lymph nodes. The generation of these tumor-specific effector cells required the presence of the tumor mass since such activity was not elicited in the lymph nodes of mice from which the tumors had been surgically excised. The results of this study show that, after treatment of tumor bearers with vitamin D₃ to eliminate GM-suppressor cells, IL-12 can induce select regional antitumor immune responses, particularly IFNγ production and cytolysis by regional lymph node cells of autologous tumor. Received: 15 December 1995 / Accepted: 22 March 1996     

Supplemental vitamin D increases serum cytokines in those with initially low 25-hydroxyvitamin D: A randomized,double blind,placebo-controlled study

The purpose of this study was to determine if vitamin D status before supplementation influences the cytokine response after supplemental vitamin D. Forty-six reportedly healthy adults (mean(SD); age, 32(7) y; body mass index (BMI), 25.3(4.5) kg/m²; serum 25-hydroxyvitamin D (25(OH)D), 34.8(12.2) ng/mL) were randomly assigned (double blind) to one of three groups: (1) placebo (n = 15), or supplemental vitamin D (cholecalciferol) at (2) 4000 (n = 14) or (3) 8000 IU (n = 17). Supplements were taken daily for 35 days. Fasting blood samples were obtained before (Baseline, Bsl) and 35-days after (35-d) supplementation. Serum 25(OH)D, 1,25-dihydroxyvitamin D (1,25(OH)D), cytokines, and intact parathyroid hormone with calcium were measured in each blood sample. Supplemental vitamin D increased serum 25(OH)D (4000 IU, ≈29%; 8000 IU, ≈57%) and 1,25(OH)D (4000 IU, ≈12%; 8000 IU, ≈38%) without altering intact parathyroid hormone or calcium. The vitamin D metabolite increases in the supplemental vitamin D groups (n = 31) were dependent on initial levels as serum 25(OH)D (r = −0.63, p < 0.05) and 1,25(OH)D (r = −0.45, p < 0.05) at Bsl correlated with their increases after supplementation. Supplemental vitamin D increased interferon (IFN)-γ and interleukin (IL)-10 in subjects that were vitamin D insufficient (serum 25(OH)D < 29 ng/mL) compared to sufficient (serum 25(OH)D ⩾ 30 ng/mL) at Bsl. We conclude that supplemental vitamin D increase a pro- and anti-inflammatory cytokine in those with initially low serum 25(OH)D.