scholarly journals Long Term Response to Circulating Angiogenic Cells, Unstimulated or Atherosclerotic Pre-Conditioned, in Critical Limb Ischemic Mice

Biomedicines ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1147
Author(s):  
Lucía Beltrán-Camacho ◽  
Margarita Jiménez-Palomares ◽  
Ismael Sanchez-Gomar ◽  
Antonio Rosal-Vela ◽  
Marta Rojas-Torres ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Limb Ischemia ◽  
Good Alternative ◽  
Severe Form ◽  
Circulating Angiogenic Cells ◽  
Long Term Effect ◽  
Proteomics Approach ◽  
Artery Disease

Critical limb ischemia (CLI), the most severe form of peripheral artery disease, results from the blockade of peripheral vessels, usually correlated to atherosclerosis. Currently, endovascular and surgical revascularization strategies cannot be applied to all patients due to related comorbidities, and even so, most patients require re-intervention or amputation within a year. Circulating angiogenic cells (CACs) constitute a good alternative as CLI cell therapy due to their vascular regenerative potential, although the mechanisms of action of these cells, as well as their response to pathological conditions, remain unclear. Previously, we have shown that CACs enhance angiogenesis/arteriogenesis from the first days of administration in CLI mice. Also, the incubation ex vivo of these cells with factors secreted by atherosclerotic plaques promotes their activation and mobilization. Herein, we have evaluated the long-term effect of CACs administration in CLI mice, whether pre-stimulated or not with atherosclerotic factors. Remarkably, mice receiving CACs and moreover, pre-stimulated CACs, presented the highest blood flow recovery, lower progression of ischemic symptoms, and decrease of immune cells recruitment. In addition, many proteins potentially involved, like CD44 or matrix metalloproteinase 9 (MMP9), up-regulated in response to ischemia and decreased after CACs administration, were identified by a quantitative proteomics approach. Overall, our data suggest that pre-stimulation of CACs with atherosclerotic factors might potentiate the regenerative properties of these cells in vivo.

Long-Term Effect of Nitric Oxide Inhibition on NA Transporter Abundance in Kidney: A Targeted Proteomics Approach.

Hypertension ◽  
2000 ◽  
Vol 36 (suppl_1) ◽  
pp. 681-681
Author(s):  
Patricia L Turner ◽  
Shyama M E Masilamani ◽  
Ivan Reyes ◽  
Mark A Knepper
Keyword(s):  
Nitric Oxide ◽  
Polyclonal Antibodies ◽  
No Synthase ◽  
Targeted Proteomics ◽  
Long Term Effects ◽  
Long Term Effect ◽  
Proteomics Approach ◽  
Synthase Inhibitor

21 Short term effects of nitric oxide (NO) on renal Na transport are well described, but long-term effects have not been investigated. To assess the role of NO on long-term regulation of Na transporter abundance along the renal tubule, we have applied a “targeted proteomics” approach. This approach uses an array of peptide-directed polyclonal antibodies to each of the major apical Na transporters and aquaporins to assess renal abundance changes in response to a given in vivo stimulus. Rats (n=6) were treated for 3 days with 30mg/kg N G -nitro-L-arginine (L-NAME), a non-selective NO synthase inhibitor, via osmotic mini-pump, while controls (n=6) received vehicle infusion. Readout was via semiquantitative immunoblotting. The table indicates the percent changes in band density in whole kidney samples for each protein target. Similar results were seen in cortical samples from the same rats, and in additional rats with identical treatment. We conclude that long-term inhibition of NO synthase with L-NAME results in a selective increase in the abundance of NCC, the thiazide-sensitive Na-Cl transporter of the distal convoluted tubule.

Strategies to Protect Hematopoietic Stem Cells from Culture-Induced Stress Conditions

2020 ◽  
Vol 15 ◽  
Author(s):  
Fatima Aerts-Kaya
Keyword(s):  
Stem Cells ◽  
Hematopoietic Stem Cells ◽  
Ex Vivo ◽  
Stress Conditions ◽  
Stress Factors ◽  
Hematopoietic Stem ◽  
Induced Stress

: In contrast to their almost unlimited potential for expansion in vivo and despite years of dedicated research and optimization of expansion protocols, the expansion of Hematopoietic Stem Cells (HSCs) in vitro remains remarkably limited. Increased understanding of the mechanisms that are involved in maintenance, expansion and differentiation of HSCs will enable the development of better protocols for expansion of HSCs. This will allow procurement of HSCs with long-term engraftment potential and a better understanding of the effects of the external influences in and on the hematopoietic niche that may affect HSC function. During collection and culture of HSCs, the cells are exposed to suboptimal conditions that may induce different levels of stress and ultimately affect their self-renewal, differentiation and long-term engraftment potential. Some of these stress factors include normoxia, oxidative stress, extra-physiologic oxygen shock/stress (EPHOSS), endoplasmic reticulum (ER) stress, replicative stress, and stress related to DNA damage. Coping with these stress factors may help reduce the negative effects of cell culture on HSC potential, provide a better understanding of the true impact of certain treatments in the absence of confounding stress factors. This may facilitate the development of better ex vivo expansion protocols of HSCs with long-term engraftment potential without induction of stem cell exhaustion by cellular senescence or loss of cell viability. This review summarizes some of available strategies that may be used to protect HSCs from culture-induced stress conditions.

scholarly journals Aη-α and Aη-β peptides impair LTP ex vivo within the low nanomolar range and impact neuronal activity in vivo

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Maria Mensch ◽  
Jade Dunot ◽  
Sandy M. Yishan ◽  
Samuel S. Harris ◽  
Aline Blistein ◽  
...  
Keyword(s):  
Neuronal Activity ◽  
Ex Vivo ◽  
Long Term Potentiation ◽  
Network Activity ◽  
Strongly Correlated ◽  
App Processing ◽  
Term Potentiation ◽  
Hippocampal Network

Abstract Background Amyloid precursor protein (APP) processing is central to Alzheimer’s disease (AD) etiology. As early cognitive alterations in AD are strongly correlated to abnormal information processing due to increasing synaptic impairment, it is crucial to characterize how peptides generated through APP cleavage modulate synapse function. We previously described a novel APP processing pathway producing η-secretase-derived peptides (Aη) and revealed that Aη–α, the longest form of Aη produced by η-secretase and α-secretase cleavage, impaired hippocampal long-term potentiation (LTP) ex vivo and neuronal activity in vivo. Methods With the intention of going beyond this initial observation, we performed a comprehensive analysis to further characterize the effects of both Aη-α and the shorter Aη-β peptide on hippocampus function using ex vivo field electrophysiology, in vivo multiphoton calcium imaging, and in vivo electrophysiology. Results We demonstrate that both synthetic peptides acutely impair LTP at low nanomolar concentrations ex vivo and reveal the N-terminus to be a primary site of activity. We further show that Aη-β, like Aη–α, inhibits neuronal activity in vivo and provide confirmation of LTP impairment by Aη–α in vivo. Conclusions These results provide novel insights into the functional role of the recently discovered η-secretase-derived products and suggest that Aη peptides represent important, pathophysiologically relevant, modulators of hippocampal network activity, with profound implications for APP-targeting therapeutic strategies in AD.

scholarly journals Assessment of Electrospun Pellethane-Based Scaffolds for Vascular Tissue Engineering

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3678
Author(s):  
Vera Chernonosova ◽  
Alexandr Gostev ◽  
Ivan Murashov ◽  
Boris Chelobanov ◽  
Andrey Karpenko ◽  
...  
Keyword(s):  
Vascular Tissue ◽  
Ex Vivo ◽  
Vascular Grafts ◽  
Wistar Rat ◽  
Graft Occlusion ◽  
Suitable Candidate ◽  
Large Animals ◽  
Cell Adhesion And Proliferation

We examined the physicochemical properties and the biocompatibility and hemocompatibility of electrospun 3D matrices produced using polyurethane Pellethane 2363-80A (Pel-80A) blends Pel-80A with gelatin or/and bivalirudin. Two layers of vascular grafts of 1.8 mm in diameter were manufactured and studied for hemocompatibility ex vivo and functioning in the infrarenal position of Wistar rat abdominal aorta in vivo (n = 18). Expanded polytetrafluoroethylene (ePTFE) vascular grafts of similar diameter were implanted as a control (n = 18). Scaffolds produced from Pel-80A with Gel showed high stiffness with a long proportional limit and limited influence of wetting on mechanical characteristics. The electrospun matrices with gelatin have moderate capacity to support cell adhesion and proliferation (~30–47%), whereas vascular grafts with bivalirudin in the inner layer have good hemocompatibility ex vivo. The introduction of bivalirudin into grafts inhibited platelet adhesion and does not lead to a change hemolysis and D-dimers concentration. Study in vivo indicates the advantages of Pel-80A grafts over ePTFE in terms of graft occlusion, calcification level, and blood velocity after 6 months of implantation. The thickness of neointima in Pel-80A–based grafts stabilizes after three months (41.84 ± 20.21 µm) and does not increase until six months, demonstrating potential for long-term functioning without stenosis and as a suitable candidate for subsequent preclinical studies in large animals.

BioMEMS Technologies for Regenerative Medicine

2008 ◽  
Vol 1139 ◽  
Author(s):  
Jeffrey T. Borenstein
Keyword(s):  
Drug Delivery ◽  
Regenerative Medicine ◽  
Drug Delivery Systems ◽  
Ex Vivo ◽  
Delivery Systems ◽  
Organ Shortage ◽  
Engineered Tissues ◽  
Drug Concentrations

AbstractThe emergence of BioMEMS fabrication technologies such as soft lithography, micromolding and assembly of 3D structures, and biodegradable microfluidics, are already making significant contributions to the field of regenerative medicine. Over the past decade, BioMEMS have evolved from early silicon laboratory devices to polymer-based structures and even biodegradable constructs suitable for a range of ex vivo and in vivo applications. These systems are still in the early stages of development, but the long-term potential of the technology promises to enable breakthroughs in health care challenges ranging from the systemic toxicity of drugs to the organ shortage. Ex vivo systems for organ assist applications are emerging for the liver, kidney and lung, and the precision and scalability of BioMEMS fabrication techniques offer the promise of dramatic improvements in device performance and patient outcomes.Ultimately, the greatest benefit from BioMEMS technologies will be realized in applications for implantable devices and systems. Principal advantages include the extreme levels of achievable miniaturization, integration of multiple functions such as delivery, sensing and closed loop control, and the ability of precision microscale and nanoscale features to reproduce the cellular microenvironment to sustain long-term functionality of engineered tissues. Drug delivery systems based on BioMEMS technologies are enabling local, programmable control over drug concentrations and pharmacokinetics for a broad spectrum of conditions and target organs. BioMEMS fabrication methods are also being applied to the development of engineered tissues for applications such as wound healing, microvascular networks and bioartificial organs. Here we review recent progress in BioMEMS-based drug delivery systems, engineered tissue constructs and organ assist devices for a range of ex vivo and in vivo applications in regenerative medicine.

scholarly journals Acute (24 h) activation of peroxisome proliferator-activated receptor-alpha (PPARalpha) reverses high-fat feeding-induced insulin hypersecretion in vivo and in perifused pancreatic islets

2003 ◽  
Vol 177 (2) ◽  
pp. 197-205 ◽  
Author(s):  
MJ Holness ◽  
ND Smith ◽  
GK Greenwood ◽  
MC Sugden
Keyword(s):  
Insulin Secretion ◽  
Ex Vivo ◽  
Peroxisome Proliferator ◽  
High Fat ◽  
Intravenous Glucose ◽  
Perifused Islets ◽  
Glucose Stimulated Insulin Secretion ◽  
Fat Feeding

Abnormal depletion or accumulation of islet lipid may be important for the development of pancreatic beta cell failure. Long-term lipid sensing by beta cells may be co-ordinated via peroxisome proliferator-activated receptors (PPARs). We investigated whether PPARalpha activation in vivo for 24 h affects basal and glucose-stimulated insulin secretion in vivo after intravenous glucose administration and ex vivo in isolated perifused islets. Insulin secretion after intravenous glucose challenge was greatly increased by high-fat feeding (4 weeks) but glucose tolerance was minimally perturbed, demonstrating insulin hypersecretion compensated for insulin resistance. The effect of high-fat feeding to enhance glucose-stimulated insulin secretion was retained in perifused islets demonstrating a stable, long-term effect of high-fat feeding to potentiate islet glucose stimulus-secretion coupling. Treatment of high-fat-fed rats with WY14,643 for 24 h reversed insulin hypersecretion in vivo without impairing glucose tolerance, suggesting improved insulin action, and ex vivo in perfused islets. PPARalpha activation only affected hypersecretion of insulin since glucose-stimulated insulin secretion was unaffected by WY14,643 treatment in vivo in control rats or in perifused islets from control rats. Our data demonstrate that activation of PPARalpha for 24 h can oppose insulin hypersecretion elicited by high-fat feeding via stable long-term effects exerted on islet function. PPARalpha could, therefore, participate in ameliorating abnormal glucose homeostasis and hyperinsulinaemia in dietary insulin resistance via modulation of islet function, extending the established requirement for PPARalpha for normal islet lipid homeostasis.

Designed multifunctional polymeric nanomedicines: long-term biodistribution and tumour accumulation of aptamer-targeted nanomaterials

2018 ◽  
Vol 54 (82) ◽  
pp. 11538-11541 ◽  
Author(s):  
N. L. Fletcher ◽  
Z. H. Houston ◽  
J. D. Simpson ◽  
R. N. Veedu ◽  
K. J. Thurecht
Keyword(s):  
Polyethylene Glycol ◽  
Pet Imaging ◽  
Hyperbranched Polymer ◽  
Ex Vivo

We report a novel multifunctional hyperbranched polymer based on polyethylene glycol (PEG) as a nanomedicine platform that facilitates longitudinal and quantitative 89Zr-PET imaging, enhancing knowledge of nanomaterial biodistribution and pharmacokinetics/pharmacodynamics both in vivo and ex vivo.

Gene therapy for critical limb ischemia: Per aspera ad astra

2021 ◽  
Vol 21 ◽  
Author(s):  
Vyacheslav Z. Tarantul ◽  
Alexander V. Gavrilenko
Keyword(s):  
Gene Therapy ◽  
Critical Limb Ischemia ◽  
Viral Vectors ◽  
Ex Vivo ◽  
Single Gene ◽  
Public Health Problem ◽  
Limb Ischemia ◽  
Therapeutic Angiogenesis ◽  
Effective Treatment Option

: Peripheral artery diseases remain a serious public health problem. Although there are many traditional methods for their treatment using conservative therapeutic techniques and surgery, gene therapy is an alternative and potentially more effective treatment option especially for “no option” patients. This review treats the results of many years of research and application of gene therapy as an example of treatment of patients with critical limb ischemia. Data on successful and unsuccessful attempts to use this technology for treating this disease are presented. Trends in changing the paradigm of approaches to therapeutic angiogenesis are noted: from viral vectors to non-viral vectors, from gene transfer to the whole organism to targeted transfer to cells and tissues, from single gene use to combination of genes; from DNA therapy to RNA therapy, from in vivo therapy to ex vivo therapy.

Anti-nociceptive and anti-inflammatory activity of synthesized novel benzoxazole derivatives

2021 ◽  
Vol 20 ◽  
Author(s):  
Mansi L. Patil ◽  
Swati S. Gaikwad ◽  
Naresh J. Gaikwad
Keyword(s):  
Cytotoxic Activity ◽  
Research Study ◽  
Ex Vivo ◽  
Immunological Response ◽  
Inflammatory Activity ◽  
Inflammatory Drugs ◽  
Anti Inflammatory ◽  
Inflammatory Effect

Introduction: Pain is an immunological response to any infection or inflammation and long term use of pain management therapy includes use of Nonsteroidal anti-inflammatory drugs which is associated with occurrence of toxicity as well as gastrointestinal bleeding. Therefore, the investigation of new analgesic and anti-inflammatory agents remains a major challenge. Aims: The objective of this research study is to undergo the pharmacological evaluation of newly synthesized benzoxazole derivatives. These novel derivatives were evaluated for anti-nociceptive, anti-inflammatory and cytotoxic activity using various in-vivo and ex-vivo methods. Methods: The study was carried out using swiss mice (adult male) weighing between 20gm to 30gm and were divided into groups containing (n=6) six animals in each group for treatment. The anti-nociceptive activity was performed by using 0.1ml of 0.6% v/v acetic acid as nociception inducer and evaluated by the diminished number of abdominal writhes. The anti-inflammatory activity was done using 0.1 ml of 2% w/v Carrageenan induced paw edema method was observed which was evaluated by calculating the percent maximum possible effect. Histopathological evaluation and cytotoxic activity of the compounds was carried out. Results: The results of this research study revealed that synthesized derivatives (a, b, c, d and e) showed promising anti-nociceptive and anti-inflammatory effect along significantly higher cytotoxic activity in MCF-7 cell lines. Conclusion: It can be concluded that synthesized derivatives (a, b, c, d and e) have potential anti-nociceptive and anti-inflammatory effect along with cytotoxic activity and certain modification in structure may result in potent activity.

scholarly journals Subcutaneous Immunization of Leishmania HSP70-II Null Mutant Line Reduces the Severity of the Experimental Visceral Leishmaniasis in BALB/c Mice

Vaccines ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 141
Author(s):  
José Carlos Solana ◽  
Laura Ramírez ◽  
Emma CL Cook ◽  
Elena Hernández-García ◽  
Silvia Sacristán ◽  
...  
Keyword(s):  
Visceral Leishmaniasis ◽  
Cell Line ◽  
Subcutaneous Administration ◽  
Chronic Phase ◽  
Severe Form ◽  
Vaccine Potential ◽  
Dilution Experiments ◽  
Subcutaneous Immunization

Leishmania infantum parasites cause a severe form of visceral leishmaniasis in human and viscerocutaneous leishmaniasis in dogs. Recently, we reported that immunization with an attenuated L. infantum cell line, lacking the hsp70-II gene, protects against the development of murine cutaneous leishmaniasis. In this work, we analyzed the vaccine potential of this cell line towards the long-term protection against murine visceral leishmaniasis. This model shows an organ-dependent evolution of the disease. The infection can resolve in the liver but chronically affect spleen and bone marrow. Twelve weeks after subcutaneous administration of attenuated L. infantum, Bagg Albino (BALB/c) mice were challenged with infective L. infantum parasites expressing the luciferase-encoding gene. Combining in vivo bioimaging techniques with limiting dilution experiments, we report that, in the initial phase of the disease, vaccinated animals presented lower parasite loads than unvaccinated animals. A reduction of the severity of liver damage was also detected. Protection was associated with the induction of rapid parasite-specific IFN-γ production by CD4+ and CD8+ T cells. However, the vaccine was unable to control the chronic phase of the disease, since we did not find differences in the parasite burdens nor in the immune response at that time point.

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