scholarly journals Placental Mesenchymal Stem Cell-Derived Extracellular Vesicles Promote Myelin Regeneration in an Animal Model of Multiple Sclerosis

Cells ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1497 ◽  
Author(s):  
Kaitlin Clark ◽  
Sheng Zhang ◽  
Sylvain Barthe ◽  
Priyadarsini Kumar ◽  
Christopher Pivetti ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Animal Model ◽  
Extracellular Vesicles ◽  
Inflammatory Diseases ◽  
Disease Onset ◽  
Symptom Improvement ◽  
High Dose ◽  
Feasible Alternative ◽  
High Doses

Mesenchymal stem/stromal cells (MSCs) display potent immunomodulatory and regenerative capabilities through the secretion of bioactive factors, such as proteins, cytokines, chemokines as well as the release of extracellular vesicles (EVs). These functional properties of MSCs make them ideal candidates for the treatment of degenerative and inflammatory diseases, including multiple sclerosis (MS). MS is a heterogenous disease that is typically characterized by inflammation, demyelination, gliosis and axonal loss. In the current study, an induced experimental autoimmune encephalomyelitis (EAE) murine model of MS was utilized. At peak disease onset, animals were treated with saline, placenta-derived MSCs (PMSCs), as well as low and high doses of PMSC-EVs. Animals treated with PMSCs and high-dose PMSC-EVs displayed improved motor function outcomes as compared to animals treated with saline. Symptom improvement by PMSCs and PMSC-EVs led to reduced DNA damage in oligodendroglia populations and increased myelination within the spinal cord of treated mice. In vitro data demonstrate that PMSC-EVs promote myelin regeneration by inducing endogenous oligodendrocyte precursor cells to differentiate into mature myelinating oligodendrocytes. These findings support that PMSCs’ mechanism of action is mediated by the secretion of EVs. Therefore, PMSC-derived EVs are a feasible alternative to cellular based therapies for MS, as demonstrated in an animal model of the disease.

scholarly journals Extracellular vesicles as mediators and markers of acute organ injury: current concepts

2021 ◽  
Author(s):  
Birte Weber ◽  
Niklas Franz ◽  
Ingo Marzi ◽  
Dirk Henrich ◽  
Liudmila Leppik
Keyword(s):  
Extracellular Vesicles ◽  
Inflammatory Diseases ◽  
Organ Injury ◽  
Isolation And Characterization ◽  
Communication Processes ◽  
Incidence And Mortality ◽  
New Biomarkers ◽  
And Function

AbstractDue to the continued high incidence and mortality rate worldwide, there is a need to develop new strategies for the quick, precise, and valuable recognition of presenting injury pattern in traumatized and poly-traumatized patients. Extracellular vesicles (EVs) have been shown to facilitate intercellular communication processes between cells in close proximity as well as distant cells in healthy and disease organisms. miRNAs and proteins transferred by EVs play biological roles in maintaining normal organ structure and function under physiological conditions. In pathological conditions, EVs change the miRNAs and protein cargo composition, mediating or suppressing the injury consequences. Therefore, incorporating EVs with their unique protein and miRNAs signature into the list of promising new biomarkers is a logical next step. In this review, we discuss the general characteristics and technical aspects of EVs isolation and characterization. We discuss results of recent in vitro, in vivo, and patients study describing the role of EVs in different inflammatory diseases and traumatic organ injuries. miRNAs and protein signature of EVs found in patients with acute organ injury are also debated.

scholarly journals Toll-Like Receptor Signaling in Airborne Burkholderia thailandensis Infection

2009 ◽  
Vol 77 (12) ◽  
pp. 5612-5622 ◽  
Author(s):  
T. Eoin West ◽  
Thomas R. Hawn ◽  
Shawn J. Skerrett
Keyword(s):  
Low Dose ◽  
Inflammatory Responses ◽  
High Dose ◽  
Tlr Signaling ◽  
Necrosis Factor Alpha ◽  
Airborne Infection ◽  
Essential Components ◽  
High Doses

ABSTRACT Melioidosis is a tropical disease endemic in southeast Asia and northern Australia caused by the gram-negative soil saprophyte Burkholderia pseudomallei. Although infection is often systemic, the lung is frequently involved. B. thailandensis is a closely related organism that at high doses causes lethal pneumonia in mice. We examined the role of Toll-like receptors (TLRs), essential components of innate immunity, in vitro and in vivo during murine B. thailandensis pneumonia. TLR2, TLR4, and TLR5 mediate NF-κB activation by B. thailandensis in transfected HEK293 or CHO cells. In macrophages, TLR4 and the adaptor molecule MyD88, but not TLR2 or TLR5, are required for tumor necrosis factor alpha production induced by B. thailandensis. In low-dose airborne infection, TLR4 is needed for early, but not late, bacterial containment, and MyD88 is essential for control of infection and host survival. TLR2 and TLR5 are not necessary to contain low-dose infection. In high-dose airborne infection, TLR2 deficiency confers a slight survival advantage. Lung and systemic inflammatory responses are induced by low-dose inhaled B. thailandensis independently of individual TLRs or MyD88. These findings suggest that redundancy in TLR signaling or other MyD88-dependent pathways may be important in pneumonic B. thailandensis infection but that MyD88-independent mechanisms of inflammation are also activated. TLR signaling in B. thailandensis infection is substantially comparable to signaling induced by virulent B. pseudomallei. These studies provide additional insights into the host-pathogen interaction in pneumonic Burkholderia infection.

scholarly journals High doses of immunoglobulin G attenuate immune aggregate-mediated complement activation by enhancing physiologic cleavage of C3b in C3bn- IgG complexes

Blood ◽  
1996 ◽  
Vol 88 (1) ◽  
pp. 184-193 ◽  
Author(s):  
HU Lutz ◽  
P Stammler ◽  
E Jelezarova ◽  
M Nater ◽  
PJ Spath
Keyword(s):  
Inflammatory Diseases ◽  
Factor H ◽  
Human Igg ◽  
Partial Protection ◽  
Beneficial Effects ◽  
High Concentrations ◽  
High Doses ◽  
Immune Aggregates

Abstract Intravenously applied human IgG has beneficial effects in treating inflammatory diseases, presumably because it has a complement attenuating role. This role of IgG was studied in vitro by following C3 activation and inactivation in sera that were supplemented with exogenous human IgG and incubated with immune aggregates. IgG added at 2 to 10 mg/mL stimulated the physiologic inactivation of C3b-containing complexes twofold to threefold in 20% sera. This, in turn, lowered the overall C3 activation by 28%, as new C3 convertases primarily assembled on C3b-containing complexes. Exogenous IgG (5 mg/mL) also stimulated inactivation of purified C3b2-IgG complexes, whereby their half-life dropped from 3–4 to 1.5 minutes in 20% serum. IgG appeared to act like a modulator of factor H and I because it did not stimulate inactivation of C3b-containing complexes in factor I-deficient serum. Thus, the known partial protection of C3bn-IgG complexes from inactivation by factor H and I was downregulated by high concentrations of IgG. The ability of high doses of IgG to stimulate complement inactivation is a novel regulatory role of IgG. This may be one of the molecular principles for its therapeutic efficacy in treating complement-mediated inflammations.

scholarly journals Fluconazole plus Cyclosporine: a Fungicidal Combination Effective against Experimental Endocarditis Due to Candida albicans

2000 ◽  
Vol 44 (11) ◽  
pp. 2932-2938 ◽  
Author(s):  
O. Marchetti ◽  
J. M. Entenza ◽  
D. Sanglard ◽  
J. Bille ◽  
M. P. Glauser ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Amphotericin B ◽  
Cyclosporine A ◽  
Test Organism ◽  
The Other ◽  
High Dose ◽  
Therapeutic Results ◽  
Fluconazole Therapy ◽  
High Doses

ABSTRACT Recent observations demonstrated that fluconazole plus cyclosporine (Cy) synergistically killed Candida albicans in vitro. This combination was tested in rats with C. albicansexperimental endocarditis. The MICs of fluconazole and Cy for the test organism were 0.25 and >10 mg/liter, respectively. Rats were treated for 5 days with either Cy, amphotericin B, fluconazole, or fluconazole-Cy. Although used at high doses, the peak concentrations of fluconazole in the serum of rats (up to 4.5 mg/liter) were compatible with high-dose fluconazole therapy in humans. On the other hand, Cy concentrations in serum (up to 4.5 mg/liter) were greater than recommended therapeutic levels. Untreated rats demonstrated massive pseudohyphal growth in both the vegetations and the kidneys. However, only the kidneys displayed concomitant polymorphonuclear infiltration. The therapeutic results reflected this dissociation. In the vegetations, only the fungicidal fluconazole-Cy combination significantly decreased fungal densities compared to all groups, including amphotericin B (P < 0.0001). In the kidneys, all regimens except the Cy regimen were effective, but fluconazole-Cy remained superior to amphotericin B and fluconazole alone in sterilizing the organs (P < 0.0001). While the mechanism responsible for the fluconazole-Cy interaction is hypothetical, this observation opens new perspectives for fungicidal combinations between azoles and other drugs.

scholarly journals Immunotherapy of a murine tumor with interleukin 2. Increased sensitivity after MHC class I gene transfection.

1987 ◽  
Vol 166 (6) ◽  
pp. 1716-1733 ◽  
Author(s):  
J S Weber ◽  
G Jay ◽  
K Tanaka ◽  
S A Rosenberg
Keyword(s):  
T Cells ◽  
Mhc Class I ◽  
Interleukin 2 ◽  
Class I ◽  
High Dose ◽  
Class I Mhc ◽  
High Doses ◽  
I Gene

We have shown that two weakly immunogenic MCA sarcomas developed in our laboratory that are sensitive to high-dose IL-2 immunotherapy express class I MHC in vivo and in vitro. Two nonimmunogenic MCA sarcomas are relatively insensitive to IL-2 therapy and express minimal or no class I MHC molecules in vivo and in vitro. To study the role of MHC in the therapy of tumors with IL-2, a class I-deficient murine melanoma, B16BL6, was transfected with the Kb class I gene. Expression of class I MHC rendered B16BL6 advanced pulmonary macrometastases sensitive to IL-2 immunotherapy. 3-d micrometastases of CL8-2, a class I transfected clone of B16BL6, were significantly more sensitive to IL-2 therapy than a control nontransfected line. Expression of Iak, a class II MHC molecule, had no effect on IL-2 therapy of transfectant pulmonary micrometastases in F1 mice. By using lymphocyte subset depletion with mAbs directed against Lyt-2, therapy of class I transfectant macrometastases with high-dose IL-2 was shown to involve an Lyt-2 cell. In contrast, regression of micrometastases treated with low-dose IL-2 involved Lyt-2+ cells, but regression mediated by high doses of IL-2 did not. We hypothesize that both LAK and Lyt-2+ T cells effect IL-2-mediated elimination of micrometastases, but only Lyt-2+ T cells are involved in macrometastatic regression. Low doses of IL-2 stimulate Lyt-2+ cells to eliminate class I-expressing micrometastases, but high doses of IL-2 can recruit LAK cells to mediate regression of micrometastases independent of class I expression. Only high-dose IL-2, mediating its effect predominantly via Lyt-2+ cells, is capable of impacting on MHC class I-expressing macrometastases. Macrometastases devoid of class I MHC antigens appear to be resistant to IL-2 therapy.

scholarly journals Dose-Dependent Differential Effect of Neurotrophic Factors on In Vitro and In Vivo Regeneration of Motor and Sensory Neurons

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Daniel Santos ◽  
Francisco Gonzalez-Perez ◽  
Xavier Navarro ◽  
Jaume del Valle
Keyword(s):  
Neurite Outgrowth ◽  
Functional Recovery ◽  
Neurotrophic Factors ◽  
Collagen Matrix ◽  
High Dose ◽  
Organotypic Cultures ◽  
High Doses ◽  
Dose Dependent

Although peripheral axons can regenerate after nerve transection and repair, functional recovery is usually poor due to inaccurate reinnervation. Neurotrophic factors promote directional guidance to regenerating axons and their selective application may help to improve functional recovery. Hence, we have characterized in organotypic cultures of spinal cord and dorsal root ganglia the effect of GDNF, FGF-2, NGF, NT-3, and BDNF at different concentrations on motor and sensory neurite outgrowth. In vitro results show that GDNF and FGF-2 enhanced both motor and sensory neurite outgrowth, NGF and NT-3 were the most selective to enhance sensory neurite outgrowth, and high doses of BDNF selectively enhanced motor neurite outgrowth. Then, NGF, NT-3, and BDNF (as the most selective factors) were delivered in a collagen matrix within a silicone tube to repair the severed sciatic nerve of rats. Quantification of Fluorogold retrolabeled neurons showed that NGF and NT-3 did not show preferential effect on sensory regeneration whereas BDNF preferentially promoted motor axons regeneration. Therefore, the selective effects of NGF and NT-3 shown in vitro are lost when they are applied in vivo, but a high dose of BDNF is able to selectively enhance motor neuron regeneration both in vitro and in vivo.

scholarly journals High-Dose Intravenous Ribavirin Therapy for Subacute Sclerosing Panencephalitis

2001 ◽  
Vol 45 (3) ◽  
pp. 943-945 ◽  
Author(s):  
Mitsuaki Hosoya ◽  
Shiro Shigeta ◽  
Shuichi Mori ◽  
Akemi Tomoda ◽  
Seiji Shiraishi ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Virus Replication ◽  
Subacute Sclerosing Panencephalitis ◽  
Alpha Interferon ◽  
High Dose ◽  
Sspe Virus ◽  
High Doses

ABSTRACT Two patients with subacute sclerosing panencephalitis (SSPE) were treated safely and effectively with high doses of intravenous ribavirin combined with intraventricular alpha interferon. The ribavirin concentrations maintained in the serum and cerebrospinal fluid were higher than those which inhibit SSPE virus replication in vitro and in vivo.

scholarly journals Hormetic effect of amyloid-beta peptide in hippocampal synaptic plasticity and memory

2021 ◽  
Vol 11 (40) ◽  
pp. 156-156
Author(s):  
Daniela Puzzo ◽  
Agostino Palmeri
Keyword(s):  
Synaptic Plasticity ◽  
Amyloid Beta ◽  
Hippocampal Slices ◽  
Reference Memory ◽  
High Dose ◽  
Low Doses ◽  
Hormetic Effect ◽  
Physiologic Function ◽  
High Doses

Background: The term hormesis refers to a biphasic dose-response phenomenon characterized by low-dose stimulation and high-dose inhibition represented by a J-shaped or U-shaped curve, depending on the parameter measured (Calabrese and Baldwin, Hum Exp Toxicol, 2002). Indeed, several, if not all, physiological molecules (i.e. glutamate, glucocorticoids, nitric oxide) are likely to present a hormetic effect, exhibiting opposite effects at high or low concentrations. In the last few years, we have focused on amyloid-beta (A), a peptide widely known because it is produced in high amounts during Alzheimer’s disease (AD). A is considered a toxic fragment causing synaptic dysfunction and memory impairment (Selkoe, Science, 2002). However, the peptide is normally produced in the healthy brain and growing evidences indicate that it might have a physiologic function. Aim: Based on previous results showing that picomolar concentrations of A42 enhance synaptic plasticity and memory (Puzzo et al, J Neurosci, 2008) and that endogenous A is necessary for synaptic plasticity and memory (Puzzo et al, Ann Neurol, 2011), the aim of our study was to demonstrate the hormetic role of A in synaptic plasticity and memory. Methods: We used 3-month old wild type mice to analyze how synaptic plasticity, measured on hippocampal slices in vitro, and spatial reference memory were modified by treatment with different doses of A (from 2 pM to 20 μM). Results: We demonstrated that A has a hormetic effect (Puzzo et al, Neurobiol Aging, 2012) with low-doses (200 pM) stimulating synaptic plasticity and memory and high-doses (≥ 200 nM) inhibiting these processes. Conclusions: Our results suggest that, paradoxically, very low doses of A might serve to enhance memory at appropriate concentrations and conditions. These findings raise several issues when designing effective and safe approaches to AD therapy.

scholarly journals Inhibition of Urease, Elastase, and β-Glucuronidase Enzymatic Activity by Applying Aqueous Extracts of Opuntia oligacantha C.F. Först Acid Fruits: In Vitro Essay under Simulated Digestive Conditions

2021 ◽  
Vol 11 (16) ◽  
pp. 7705
Author(s):  
Gabriela Medina-Pérez ◽  
Laura Peralta-Adauto ◽  
Laura Afanador-Barajas ◽  
Fabián Fernández-Luqueño ◽  
Elizabeth Pérez-Soto ◽  
...  
Keyword(s):  
Bioactive Compounds ◽  
Inflammatory Diseases ◽  
Strong Acid ◽  
Aqueous Extracts ◽  
Inhibition Activity ◽  
Gastrointestinal Conditions ◽  
Excessive Intake ◽  
Anti Inflammatory ◽  
High Doses

Non-communicable diseases such as gastric inflammatory diseases and the hepatic pathologies are mainly related to bad lifestyle habits such as recurrent consumption of non-steroidal anti-inflammatory drugs (NSAIDs), excessive intake of alcohol, tobacco, steroids (high doses), alkaline agents, strong acid foods, and high-fat food, and Helicobacter pylori infections, among others. The fruit of Opuntia oligacantha C.F. Först var. Ulapa (xoconostle) is currently being studied due its nutritional and functional properties. The objective of the present study was to evaluate gastroprotective, anti-inflammatory, and hepatoprotective activities of different parts of xoconostle fruit by establishing in vitro simulated gastrointestinal conditions. Four treatments were established to test aqueous extracts (pericarp (P), mesocarp (M), endocarp (E) and whole fruit (W)). The quantified bioactive compounds were the total phenols, flavonoids, tannins, and betalains. The enzymatic assays were: urease, elastase, and β-glucuronidase. Significant differences (p < 0.05) of bioactive compounds content were measured in xoconostle extracts, the highest concentration was found in W (phenols 313 mg GAE/100 g, flavonoids 189 mg QE/100 g, tannins 71 mg CATE/100 g). The betalains content was higher in E; 17 mg/100 g significant differences were observed (p < 0.05) in the enzymatic inhibitions test (urease, elastase and β-glucuronidase), where W presented the highest inhibition activity (86%, 79%, and 84%), respectively. Bioactive compounds after in vitro gastrointestinal tests were maintained above 60% enzymatic inhibition activity.

Influence of Angiotensin II, Ouabain and Hydrostatic Pressure on Inulin and Electrolyte Concentration of Fluid Perfusing Pig Carotid Arteries in Vitro

1979 ◽  
Vol 56 (5) ◽  
pp. 445-453 ◽  
Author(s):  
J. K. Healy ◽  
A. J. Elliott ◽  
I. J. Oweczkin
Keyword(s):  
Angiotensin Ii ◽  
Hydrostatic Pressure ◽  
Arterial Pressure ◽  
Carotid Arteries ◽  
Sodium Concentration ◽  
High Dose ◽  
Electrolyte Homeostasis ◽  
Arterial Contraction ◽  
High Doses

1. Angiotensin II was infused into isolated, perfused pig carotid arteries. The perfusate leaving the arteries was sampled into an Auto-analyzer system which continuously monitored its composition. Arterial pressure was recorded. 2. Low, subpressor doses of angiotensin II raised the perfusate potassium concentration, whereas high doses, which produced contraction, lowered perfusate potassium and sodium concentrations. Inulin and chloride concentrations did not change. 3. The elevation of perfusate potassium with low angiotensin II dosage was appreciable compared with that caused by high doses of ouabain. 4. Neurotransmitter blockade did not alter the low- and high-dose angiotensin II effects. In other sequential dose studies, valine5-angiotensin II and isoleucine5-angiotensin II did not differ in their effects on perfusate composition or arterial contraction. 5. Mechanically increased hydrostatic pressure lowered perfusate sodium concentration, so that increased arterial pressure might have contributed to this aspect of high-dose angiotensin II effects. 6. These effects of angiotensin II might have physiological significance in relation to arterial smooth muscle and to electrolyte homeostasis.

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