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Theofilos Poutahidis Sean M. Kearney Tatiana Levkovich Peimin Qi Bernard J. Varian Jessica R. Lakritz Yassin M. Ibrahim Antonis Chatzigiagkos Eric J. Alm Susan E. Erdman 《PloS one》2013,8(10)
Wound healing capability is inextricably linked with diverse aspects of physical fitness ranging from recovery after minor injuries and surgery to diabetes and some types of cancer. Impact of the microbiome upon the mammalian wound healing process is poorly understood. We discover that supplementing the gut microbiome with lactic acid microbes in drinking water accelerates the wound-healing process to occur in half the time required for matched control animals. Further, we find that Lactobacillus reuteri enhances wound-healing properties through up-regulation of the neuropeptide hormone oxytocin, a factor integral in social bonding and reproduction, by a vagus nerve-mediated pathway. Bacteria-triggered oxytocin serves to activate host CD4+Foxp3+CD25+ immune T regulatory cells conveying transplantable wound healing capacity to naive Rag2-deficient animals. This study determined oxytocin to be a novel component of a multi-directional gut microbe-brain-immune axis, with wound-healing capability as a previously unrecognized output of this axis. We also provide experimental evidence to support long-standing medical traditions associating diet, social practices, and the immune system with efficient recovery after injury, sustained good health, and longevity. 相似文献
3.
Is a rise in intracellular concentration of free calcium necessary or sufficient for stimulated cytoskeletal-associated actin? 总被引:14,自引:10,他引:4 下载免费PDF全文
R I Sha'afi J Shefcyk R Yassin T F Molski M Volpi P H Naccache J R White M B Feinstein E L Becker 《The Journal of cell biology》1986,102(4):1459-1463
The addition of the calcium ionophore A23187 to rabbit neutrophils increases the amount of actin associated with the cytoskeleton regardless of the presence or absence of calcium in the incubation medium. In the presence of extracellular calcium, the effect of A23187 is biphasic with respect to concentration. The action of the ionophore is rapid, transient, and is inhibited by pertussis toxin, hyperosmolarity, and quinacrine. On the other hand, the addition of pertussis toxin or hyperosmolarity has small if any, effect on the rise in intracellular calcium produced by A23187. While quinacrine does not affect the fMet-Leu-Phe-induced increase in cytoskeletal actin and the polyphosphoinositide turnover, its addition inhibits completely the stimulated increase in Ca-influx produced by the same stimulus. The results presented here suggest that a rise in the intracellular concentration of free calcium is neither necessary nor sufficient for the stimulated increase in cytoskeletal-associated actin. A possible relationship between the lipid remodeling stimulated by chemoattractants and the increased cytoskeletal actin is discussed. 相似文献
4.
The inhibition of neutrophil granule enzyme secretion and chemotaxis by pertussis toxin 总被引:21,自引:2,他引:19 下载免费PDF全文
E L Becker J C Kermode P H Naccache R Yassin M L Marsh J J Munoz R I Sha'afi 《The Journal of cell biology》1985,100(5):1641-1646
Pertussis toxin treatment of rabbit peritoneal neutrophils causes a concentration-dependent inhibition of granule enzyme secretion induced by formylmethionyl-leucyl-phenylalanine, C5a, and leukotriene B4. It also inhibits chemotaxis induced by formylmethionyl-leucyl-phenylalanine. The same toxin treatment, however, has no effect on granule enzyme secretion induced by the calcium ionophore A23187 or phorbol 12-myristate 13-acetate. Moreover, pertussis toxin treatment does not affect either the number or affinity of the formylpeptide receptors on the neutrophil nor does it have any effect on the unstimulated levels of cyclic AMP (cAMP) or the transient rise in cAMP induced by chemotactic factor stimulation in these cells. We hypothesize that pertussis toxin, as in other cells, interacts with a GTP binding regulatory protein identical with or analogous to either Ni or transducin which mediates the receptor-induced inhibition or activation of a target protein or proteins required in neutrophil activation. The nature of the target protein is unknown, but it is not the catalytic unit of adenylate cyclase. The target protein acts after binding of chemotactic factor to its receptor in the sequence that leads to the receptor-induced rise in intracellular Ca2+. It does not affect the responses elicited by the direct introduction of calcium into the cells or the activity of protein kinase C. 相似文献
5.
Chemotactic factor causes rapid decreases in phosphatidylinositol,4,5-bisphosphate and phosphatidylinositol 4-monophosphate in rabbit neutrophils 总被引:20,自引:0,他引:20
M Volpi R Yassin P H Naccache R I Sha'afi 《Biochemical and biophysical research communications》1983,112(3):957-964
Stimulation of rabbit neutrophils prelabeled with 32P by the synthetic chemotactic peptide f-Met-Leu-Phe induces a rapid decrease in the radioactivity in both phosphatidylinositol, 4,5 bis phosphate and phosphatidylinositol 4-monophosphate. The mean +/- standard error of the mean values of the maximum decrease in phosphatidylinositol, 4,5 bis phosphate occurred at 10 seconds following stimulation and is equal to 19 +/- 3% of the control value. The corresponding value for phosphatidylinositol 4-monophosphate occurred at 60 seconds following stimulation and is equal to 37 +/- 7% of the control value. On the other hand, the radioactivity in phosphatidic acid and lysophospholipids increased continuously with time following stimulation. The relationship of these changes to calcium release and neutrophil activation is discussed. 相似文献
6.
Effects of the Phosphatase Inhibitors Calyculin A and Okadaic Acid on Acetylcholine Synthesis and Content of Rat Hippocampal Formation 总被引:2,自引:2,他引:0
Abstract: The biochemical mechanisms involved in the regulation of acetylcholine (ACh) turnover are poorly understood. In the experiments reported here, we examined whether inhibition of the serine/threonine phosphatases 1 and 2A by calyculin A or okadaic acid alters ACh synthesis by rat hippocampal preparations. With hippocampal slices, calyculin A (50 n M ) and okadaic acid (50 n M ) reduced significantly ( p < 0.01) the synthesis of [3 H]ACh from [3 H]choline. Both calyculin A and okadaic acid produced significant depletion of endogenous tissue ACh in a concentration-dependent manner ( p < 0.01). This depletion was not the result of a drug-induced increase of spontaneous ACh release, which was not changed significantly ( p > 0.7) by either drug. Choline acetyltransferase (ChAT) activity from tissue exposed to calyculin A or okadaic acid was reduced in a concentration-dependent manner ( p < 0.05), but these phosphatase inhibitors did not act directly on ChAT in vitro; i.e., enzymatic activity was not altered significantly ( p > 0.4) in the presence of calyculin A or okadaic acid. Both high-affinity and low-affinity [3 H]choline uptake by hippocampal synaptosomes were reduced significantly in a concentration-dependent manner in the presence of calyculin A or okadaic acid; these agents reduced V max values for high- and low-affinity choline uptake ( p < 0.01) with no significant change in K m values ( p > 0.1), indicating a noncompetitive inhibition. Taken together, these data suggest that phosphatase activity plays a role in presynaptic central cholinergic nerve terminal function, in particular in the modulation of ACh synthesis. 相似文献
7.
This study was carried out on the transported bed soil dredged from the outlet of Lake Burullus to the Mediterranean Sea and deposited nearby, forming by this way new land that underwent a primary plant succession. The multi-methodological approach comprised floristic inventories, vegetation sampling and soil composition analyses of the study site in order to detect the crucial parameters controlling the plant resettlement on recently deposited soil as related to time, local micro-topography and substrate characteristics. Floristic composition was assessed for the first 10 years of primary succession (2001–2010) on 18 stands of the area, distributed on basement, slope stands and plateau of the landfill, respectively. Vegetation surveys were the basis of multivariate analyses of the vegetation and soil data using TWINSPAN, DCA and CCA. Relationships between the edaphic gradients, floristic composition and species diversity were assessed. 相似文献
8.
Mohamed A. Farag Dalia A. Al‐Mahdy Riham Salah El Dine Sherifa Fahmy Aymen Yassin Andrea Porzel Wolfgang Brandt 《化学与生物多样性》2015,12(6):955-962
Bacterial wilts of potato, tomato, pepper, and or eggplant caused by Ralstonia solanacearum are among the most serious plant diseases worldwide. In this study, the issue of developing bactericidal agents from natural sources against R. solanacearum derived from plant extracts was addressed. Extracts prepared from 25 plant species with antiseptic relevance in Egyptian folk medicine were screened for their antimicrobial properties against the potato pathogen R. solancearum by using the disc‐zone inhibition assay and microtitre plate dilution method. Plants exhibiting notable antimicrobial activities against the tested pathogen include extracts from Acacia arabica and Punica granatum. Bioactivity‐guided fractionation of A. arabica and P. granatum resulted in the isolation of bioactive compounds 3,5‐dihydroxy‐4‐methoxybenzoic acid and gallic acid, in addition to epicatechin. All isolates displayed significant antimicrobial activities against R. solanacearum (MIC values 0.5–9 mg/ml), with 3,5‐dihydroxy‐4‐methoxybenzoic acid being the most effective one with a MIC value of 0.47 mg/ml. We further performed a structure–activity relationship (SAR) study for the inhibition of R. solanacearum growth by ten natural, structurally related benzoic acids. 相似文献
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Alphonse Ouédraogo Alfred B. Tiono Désiré Kargougou Jean Baptiste Yaro Esperance Ouédraogo Youssouf Kaboré David Kangoye Edith C. Bougouma Adama Gansane Noelie Henri Amidou Diarra Souleymane Sanon Issiaka Soulama Amadou T. Konate Nora L. Watson Valerie Brown Jenny Hendriks Maria Grazia Pau Isabella Versteege Edison Wiesken Jerald Sadoff Issa Nebie Sodiomon B. Sirima 《PloS one》2013,8(11)