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1.
J Perinatol ; 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38688998

ABSTRACT

OBJECTIVE: Intraventricular hemorrhage (IVH) is a common cause of preterm brain injury. Fresh parent's own milk (POM) contains pluripotent stem cells (SCs) that produce neuronal cells in-vitro. The permeable neonatal blood brain barrier potentially allows SC delivery. We performed the first prospective trial (clinicaltrials.gov NCT04225286) of feasibility of intranasal POM (IPOM) in preterm infants with IVH and described SC content of POM samples. STUDY DESIGN: 37 Infants (mean gestation 27.7 ± 2.6 weeks, birthweight 1030 ± 320 g) with IVH (35.1% grade IV) were recruited from two tertiary Toronto NICUs. IPOM was given ideally twice daily until 28 days of age. Tolerance and adverse reactions were collected and 162 administering providers surveyed. RESULTS: There were no major adverse reactions. Provider surveys suggested acceptability, although potential provider and subject stress requires further study. Milk cell analysis suggests wide variability between parents. CONCLUSIONS: This phase 1 study demonstrated IPOM was tolerated and feasible in preterm infants.

2.
NPJ Regen Med ; 8(1): 45, 2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37626067

ABSTRACT

Cell-based therapeutics are promising interventions to repair ischemic cardiac tissue. However, no single cell type has yet been found to be both specialized and versatile enough to heal the heart. The synergistic effects of two regenerative cell types including endothelial colony forming cells (ECFC) and first-trimester human umbilical cord perivascular cells (FTM HUCPVC) with endothelial cell and pericyte properties respectively, on angiogenic and regenerative properties were tested in a rat model of myocardial infarction (MI), in vitro tube formation and Matrigel plug assay. The combination of FTM HUCPVCs and ECFCs synergistically reduced fibrosis and cardiomyocyte apoptosis, while promoting favorable cardiac remodeling and contractility. These effects were in part mediated by ANGPT2, PDGF-ß, and VEGF-C. PDGF-ß signaling-dependent synergistic effects on angiogenesis were also observed in vitro and in vivo. FTM HUCPVCs and ECFCs represent a cell combination therapy for promoting and sustaining vascularization following ischemic cardiac injury.

3.
Cancer Lett ; 501: 133-146, 2021 03 31.
Article in English | MEDLINE | ID: mdl-33387641

ABSTRACT

Chemotherapies can cause germ cell depletion and gonadal failure. When injected post-chemotherapy, mesenchymal stromal cells (MSCs) from various sources have been shown to have regenerative effects in rodent models of chemotherapy-induced gonadal injury. Here, we evaluated two properties of a novel source of MSC, first trimester (FTM) human umbilical cord perivascular cells (HUCPVCs) (with increased regenerative potential compared to older sources), that may render them a promising candidate for chemotherapeutic gonadal injury prevention. Firstly, their ability to resist the cytotoxic effects of cyclophosphamide (CTX) in vitro, as compared to term HUCPVCs and bone marrow cells (BMSCs); and secondly, whether they prevent gonadal dysfunction if delivered prior to gonadotoxic therapy in vivo. BMSC, FTM HUCPVC, term HUCPVC, and control NTERA2 cells were treated with moderate (150 µmol/L) and high (300 µmol/L) doses of CTX in vitro. Viability, proliferative capacity, mesenchymal cell lineage markers and differentiation capacity, immunogenicity, and paracrine gene expression were assessed. CTX was administered to Wistar rats 2 days following an intra-ovarian injection of FTM HUCPVC. HUCPVC survival and ovarian follicle numbers were assessed using histological methods. We conclude that FTM HUCPVC maintain key regenerative properties following chemotherapy exposure and that pre-treatment with these cells may prevent CTX-induced ovarian damage in vivo. Therefore, HUCPVCs are promising candidates for fertility preservation.


Subject(s)
Cyclophosphamide/pharmacology , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/drug effects , Regeneration/physiology , Umbilical Cord/cytology , Umbilical Cord/drug effects , Animals , Cell Proliferation/drug effects , Cell Survival/drug effects , Cells, Cultured , Cyclophosphamide/adverse effects , Dose-Response Relationship, Drug , Female , Fertility Preservation , Humans , Ovary/drug effects , Rats , Rats, Wistar , Regeneration/drug effects , Umbilical Cord/transplantation
4.
Angiogenesis ; 23(2): 131-144, 2020 05.
Article in English | MEDLINE | ID: mdl-31576475

ABSTRACT

BACKGROUND: Perivascular cells (PVC) and their "progeny," mesenchymal stromal cells (MSC), have high therapeutic potential for ischemic diseases. While hypoxia can increase their angiogenic properties, the other aspect of ischemic conditions-glucose shortage-is deleterious for MSC and limits their therapeutic applicability. Regenerative cells in developing vascular tissues, however, can adapt to varying glucose environment and react in a tissue-protective manner. Placental development and fetal insulin production generate different glucose fluxes in early and late extraembryonic tissues. We hypothesized that FTM HUCPVC, which are isolated from a developing vascular tissue with varying glucose availability react to low-glucose conditions in a pro-angiogenic manner in vitro. METHODS: Xeno-free (Human Platelet Lysate 2.5%) expanded FTM (n = 3) and term (n = 3) HUCPVC lines were cultured in low (2 mM) and regular (4 mM) glucose conditions. After 72 h, the expression (Next Generation Sequencing) and secretion (Proteome Profiler) of angiogenic factors and the functional angiogenic effect (rat aortic ring assay and Matrigel™ plug) of the conditioned media were quantified and statistically compared between all cultures. RESULTS: Low-glucose conditions had a significant post-transcriptional inductive effect on FTM HUCPVC angiogenic factor secretion, resulting in significantly higher VEGFc and Endothelin 1 release in 3 days compared to term counterparts. Conditioned media from low-glucose FTM HUCPVC cultures had a significantly higher endothelial network enhancing effect compared to all other experimental groups both in vitro aortic ring assay and in subcutan Matrigel™ plugs. Endothelin 1 depletion of the low-glucose FTM HUCPVC conditioned media significantly diminished its angiogenic effect CONCLUSIONS: FTM HUCPVC isolated from an early extraembryonic tissue show significant pro-angiogenic paracrine reaction in low-glucose conditions at least in part through the excess release of Endothelin 1. This can be a substantial advantage in cell therapy applications for ischemic injuries.


Subject(s)
Endothelin-1/metabolism , Endothelin-1/pharmacology , Glucose/pharmacology , Mesenchymal Stem Cells/drug effects , Neovascularization, Physiologic/drug effects , Umbilical Cord/cytology , Angiogenesis Inducing Agents/metabolism , Angiogenesis Inducing Agents/pharmacology , Animals , Cell Differentiation/drug effects , Cell- and Tissue-Based Therapy , Cells, Cultured , Culture Media, Conditioned/pharmacology , Female , Gestational Age , Glucose/deficiency , Guided Tissue Regeneration/methods , Humans , Mesenchymal Stem Cells/physiology , Pericytes/cytology , Pericytes/drug effects , Pericytes/physiology , Pregnancy , Pregnancy Trimester, First/physiology , Rats , Term Birth/physiology
5.
Biol Open ; 8(7)2019 Jul 25.
Article in English | MEDLINE | ID: mdl-31345790

ABSTRACT

High quality cell cultures require reliable laboratory practices. Today's small-scale in vitro cell culture format is dominated by circular topology vessels, with the inherent disadvantage of secondary flow induced each time the cell cultures are repositioned. The secondary flow generates uneven sedimentation and adherence that negatively impacts cell culture quality. Here we show a modification of the circular culture vessel that abrogates these disturbances. Cell culture wells were augmented with a central column to diminish secondary flow. Human carcinoma cell lines (BeWo, JEG-3), mesenchymal stem cells [human umbilical cord perivascular cells (HUCPVC)] and mouse embryonic fibroblasts (MEF) were cultured in both column-augmented and regular culture wells. Human carcinoma cell cultures showed even cell densities and significantly more viable cells in column-augmented vessels. In FTM HUCPVC cultures, cell surface MSC marker (CD90, CD105) expression and cell differentiation-related gene expression patterns were significantly more homogeneous in column-augmented vessels. MEF cells in column-augmented culture vessels showed a more consistent expression of IGF-1. Column-augmented cell culture vessels significantly improve the homogeneity of adherent cell cultures by mitigating the adverse effect of the secondary flow.This article has an associated First Person interview with the first author of the paper.

6.
Arch Pharm Res ; 39(7): 878-86, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27215829

ABSTRACT

In an effort to identify a microbial enzyme that can be useful as a fungicide and biodegradation agent of chitinous wastes, a chitinase (Chi242) was purified from the culture supernatant of Streptomyces anulatus CS242 utilizing powder of shrimp shell wastes as a sole carbon source. It was purified employing ammonium sulfate precipitation and gel permeation chromatography techniques. The molecular weight of the purified chitinase was ~38 kDa by SDS-PAGE. The N-terminal amino acid sequence (A-P-G-A-P-G-T-G-A-L) showed close similarity to those of other Streptomyes chitinases. The purified enzyme displayed optimal activity at pH 6.0 and 50 °C respectively. It showed substantial thermal stability for 2 h at 30-60 °C, and exhibited broad pH stability in the range 5.0-13.0 for 48 h at 4 °C. Scanning electron microscopy confirmed the ability of this enzyme to adsorb onto solid shrimp bio-waste and to degrade chitin microfibers. Chi242 could proficiently convert colloidal chitin to N-acetyl glucosamine (GlcNAc) and N-acetyl chitobiose (GlcNAc)2 signifying that this enzyme is suitable for bioconversion of chitin waste. In addition, it exerted an effective antifungal activity towards fungal pathogen signifying its role as a biocontrol agent. Thus, a single microbial cell of Streptomyces anulatus CS242 justified its dual role.


Subject(s)
Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Chitinases/isolation & purification , Chitinases/pharmacology , Streptomyces/enzymology , Antifungal Agents/metabolism , Aspergillus niger/drug effects , Aspergillus niger/physiology , Biodegradation, Environmental , Chitinases/metabolism , Enzyme Activation/drug effects , Enzyme Activation/physiology , Substrate Specificity/drug effects , Substrate Specificity/physiology
7.
Oncol Lett ; 11(3): 1866-1872, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26998091

ABSTRACT

Maintenance of a neutral intracellular pH (pHi) is favorable for the survival of tumors, and maintenance of highly acidic extracellular pH (pHe) facilitates tumor invasiveness. The aim of the present study was to investigate the antitumor effects of lactate calcium salt (CaLa), 5-indanesulfonamide (IS) and α-cyano-4-hydroxycinnamic acid (CA) via pH regulation in colon cancer cells. HCT116 cells were treated with CaLa, IS, CA and combinations of the three. Subsequently, the concentration of intracellular lactate was determined. pHi and pHe were measured using cell lysates and culture media. Colony formation assay, cell viability assay and western blot analysis were additionally performed to analyze the consequences of the pH changes. CaLa, IS, CA and combination treatments induced an increase in the concentration of intracellular lactate. Lactate influx into the tumor microenvironment produced an acidic pHi in colon cancer cells. Consequently, colony formation and cell viability were significantly decreased, as well as poly(adenosine diphosphate-ribose) polymerase degradation. The tumor microenvironment may be exploited therapeutically by disrupting the mechanism that regulates pHi, leading to cell apoptosis. The present study indicated that treatment with CaLa, IS and CA induced intracellular acidification via lactate influx, causing apoptosis of colon cancer cells. Additionally, the findings suggested that the combination of CaLa with IS and CA may enhance antitumor activity, and may provide a potential therapeutic approach for the treatment of colon cancer.

8.
PLoS One ; 10(1): e0116984, 2015.
Article in English | MEDLINE | ID: mdl-25629974

ABSTRACT

Cancer cell motility is a key phenomenon regulating invasion and metastasis. Focal adhesion kinase (FAK) plays a major role in cellular adhesion and metastasis of various cancers. The relationship between dietary supplementation of calcium and colon cancer has been extensively investigated. However, the effect of calcium (Ca2+) supplementation on calpain-FAK-motility is not clearly understood. We sought to identify the mechanism of FAK cleavage through Ca2+ bound lactate (CaLa), its downstream signaling and role in the motility of human colon cancer cells. We found that treating HCT116 and HT-29 cells with CaLa immediately increased the intracellular Ca2+ (iCa2+) levels for a prolonged period of time. Ca2+ influx induced cleavage of FAK into an N-terminal FAK (FERM domain) in a dose-dependent manner. Phosphorylated FAK (p-FAK) was also cleaved in to its p-N-terminal FAK. CaLa increased colon cancer cells motility. Calpeptin, a calpain inhibitor, reversed the effects of CaLa on FAK and pFAK cleavage in both cancer cell lines. The cleaved FAK translocates into the nucleus and modulates p53 stability through MDM2-associated ubiquitination. CaLa-induced Ca2+ influx increased the motility of colon cancer cells was mediated by calpain activity through FAK and pFAK protein destabilization. In conclusion, these results suggest that careful consideration may be given in deciding dietary Ca2+ supplementation to patient undergoing treatment for metastatic cancer.


Subject(s)
Calcium Compounds/pharmacology , Calcium/metabolism , Calpain/metabolism , Cell Movement/drug effects , Colonic Neoplasms/metabolism , Lactates/pharmacology , Cell Adhesion/drug effects , Cell Line , Colonic Neoplasms/pathology , Focal Adhesion Protein-Tyrosine Kinases/metabolism , HT29 Cells , Humans , Phosphorylation , Signal Transduction/drug effects , Wound Healing/drug effects
9.
Appl Biochem Biotechnol ; 172(3): 1377-89, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24197522

ABSTRACT

The aim of this present study was to produce a microbial enzyme that can potentially be utilized for the enzymatic transesterification of waste cooking oil. To that end, an extracellular lipase was isolated and purified from the culture broth of Streptomyces sp. CS273. The molecular mass of purified lipase was estimated to be 36.55 kDa by SDS PAGE. The optimum lipolytic activity was obtained at alkaline pH 8.0 to 8.5 and temperature 40 °C, while the enzyme was stable in the pH range 7.0 ∼ 9.0 and at temperature ≤40 °C. The lipase showed highest hydrolytic activity towards p-nitrophenyl myristate (C14). The lipase activity was enhanced by several salts and detergents including NaCl, MnSo4, and deoxy cholic acid, while phenylmethylsulfonyl fluoride at concentration 10 mM inhibited the activity. The lipase showed tolerance towards different organic solvents including ethanol and methanol which are commonly used in transesterification reactions to displace alcohol from triglycerides (ester) contained in renewable resources to yield fatty acid alkyl esters known as biodiesel. Applicability of the lipase in transesterification of waste cooking oil was confirmed by gas chromatography mass spectrometry analysis.


Subject(s)
Biofuels , Lipase/metabolism , Refuse Disposal , Esterification , Lipase/chemistry , Lipase/isolation & purification , Oils/chemistry , Solvents/chemistry , Streptomyces/enzymology
10.
Arch Pharm Res ; 36(8): 973-80, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23636886

ABSTRACT

Antibiotic activity against various gram positive bacteria including Staphylococcus aureus and Enterococcus was ascertained from a soil-isolated microbial strain Streptomyces sp. CS392. The antibiotic activity of the strain was maximized by using a dual-stage, multivariate statistical optimization framework based on the response surface methodology considering a lab-scale fermentation process. Multiple nutrient constituents of the fermentation broth were jointly optimized in the first stage, while the fermentation culture conditions were optimized in the subsequent stage. Based on the empirical models derived from the dual-stage statistical optimization framework, 39.79 % of cumulative enhancement in the antibiotic activity was obtained (analytically) at the concurrent optimal settings (Optimal nutrient composition for the first stage of optimization: 29.82 glucose, 7.6 peptone, 4.678 MgCl2 and 0.5005 g/l casamino acid; and optimal fermentation condition for the second stage of optimization: incubation period 47.55 h; incubation temperature 29.15 °C; and pH 8.36). The analytically depicted enhancement in the antibiotic activity was validated experimentally.


Subject(s)
Anti-Bacterial Agents/metabolism , Enterococcus/metabolism , Fermentation/physiology , Staphylococcus aureus/metabolism , Streptomyces/metabolism , Anti-Bacterial Agents/chemistry , Enterococcus/chemistry , Microbial Sensitivity Tests/methods , Multivariate Analysis , Staphylococcus aureus/chemistry , Streptomyces/chemistry
11.
Thromb Res ; 129(2): 176-82, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21982334

ABSTRACT

INTRODUCTION: The prevalence of cardiovascular diseases, one of the major causes of worldwide mortality, is being increasingly reported. Safer, more effective, and less expensive thrombolytic drugs can possibly overcome the underlying problems associate with current thrombolytic drugs. METHODS: A thrombolytic enzyme was purified and characterized from a Streptomyces strain. Carrageenan induced tail-thrombosis mice model was used to evaluate in vivo antithrombotic effect of the enzyme. RESULTS: First 15N-terminal amino acids of the purified enzyme were IAGGQAIYAGGGRRS, which are significantly different from the reported fibrinolytic enzymes. The enzyme exhibited 14.3±2.3-fold stronger thrombolytic activity than that of plasmin. In carrageenan induced tail-thrombosis model, the enzyme caused reduction in frequency of thrombus. Tail-thrombus of the enzyme treated group was significantly shorter than the physiological saline treated group and the thrombus decrement was correlated with the enzyme dose. CONCLUSIONS: The enzyme purified from the Streptomyces strain can be a potential candidate for the treatment of thrombosis.


Subject(s)
Disease Models, Animal , Enzyme Therapy , Enzymes/chemistry , Fibrinolytic Agents/therapeutic use , Streptomyces/enzymology , Venous Thrombosis/drug therapy , Venous Thrombosis/physiopathology , Animals , Carrageenan , Enzyme Activation , Enzyme Stability , Humans , Mice , Mice, Inbred ICR , Tail/blood supply , Tail/drug effects , Treatment Outcome , Venous Thrombosis/diagnosis
12.
Bioprocess Biosyst Eng ; 35(1-2): 247-54, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21909674

ABSTRACT

With the aim of isolating new microbes capable of producing strong antimicrobial substances, strain CS392 was screened from 700 soil isolates preserved in our laboratory. The strain was related to genus Streptomyces based on various characteristics. Three highly active antimicrobial compounds, C1, C2 and C3, produced by the strain were purified by solvent extraction followed by silica gel column chromatography. These compounds were highly active against various Gram-positive resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Staphylococcus aureus (VRSA), and vancomycin-resistant Enterococcus (VRE). Among three, C3 was the most active against MRSA and VRSA with minimal inhibitory concentration (MIC) of 2 µg/ml while C2 and C3 had MIC values of 4 µg/ml for the strains. In case of Bacillus subtilis ATCC6633, C1 and C3 were more effective with MIC values of 0.5 µg/ml than C2 with MIC of 2 µg/ml. Those antibiotics were variably active (MIC of 4-32 µg/ml) against Micrococcus luteus ATCC 9341, Enterococcus faecalis ATCC 29212, Mycobacterium smegmatis ATCC 9341 and VRE.


Subject(s)
Anti-Infective Agents/chemistry , Anti-Infective Agents/metabolism , Streptomyces/classification , Streptomyces/metabolism , Anti-Infective Agents/isolation & purification , Species Specificity , Streptomyces/isolation & purification
13.
Appl Biochem Biotechnol ; 162(5): 1457-70, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20195792

ABSTRACT

Organic solvent- and detergent-resistant proteases are important from an industrial viewpoint. However, they have been less frequently reported and only few of them are from actinomycetes. A metalloprotease from Streptomyces olivochromogenes (SOMP) was purified by ion exchange with Poros HQ and gel filtration with Sepharose CL-6B. Apparent molecular mass of the enzyme was estimated to be 51 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gelatin zymography. The activity was optimum at pH 7.5 and 50 degrees C and stable between pH 7.0 and 10.0. SOMP was stable below 45 degrees C and Ca(2+) increased its thermostability. Ca(2+) enhanced while Co(2+), Cu(2+), Zn(2+), Mn(2+), and Fe(2+) inhibited the activity. Ethylenediaminetetraacetic acid and ethylene glycol-bis (beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid, but not phenylmethylsulfonyl fluoride, aprotinin, and pefabloc SC, significantly suppressed the activity, suggesting that it might be a metalloprotease. Importantly, it is highly resistant against various detergents, organic solvents, and oxidizing agents, and the activity is enhanced by H(2)O(2). The enzyme could be a novel protease based on its origin and peculiar biochemical properties. It may be useful in biotechnological applications especially for organic solvent-based enzymatic synthesis.


Subject(s)
Alkalies/metabolism , Metalloproteases/isolation & purification , Organic Chemicals/pharmacology , Oxidants/pharmacology , Solvents/pharmacology , Streptomyces/enzymology , Chromatography, Gel , Detergents/pharmacology , Electrophoresis, Polyacrylamide Gel , Enzyme Stability/drug effects , Hydrogen-Ion Concentration/drug effects , Kinetics , Metalloproteases/antagonists & inhibitors , Metals/pharmacology , Molecular Weight , Protease Inhibitors/pharmacology , Reducing Agents/pharmacology , Streptomyces/drug effects , Temperature
14.
Arch Pharm Res ; 32(10): 1461-7, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19898811

ABSTRACT

An extracellular phospholipase D (PLD(St)) was purified from Streptomyces tendae by two successive chromatographic steps on Sepharose CL-6B and DEAE-Sepharose CL-6B. Molecular weight of the PLD(St) was estimated to be approximately 43 kDa by sodium dodecyl sulfatepolyacrylamide gel electrophoresis. Maximal activity was at pH 8 and 60 degrees C, and the enzyme was stable at or below 60 degrees C and between pH 8 and 10, when assayed after 1.5 and 24 h, respectively. The enzyme activity had an absolute requirement of Ca(2+), and the maximum activity was at 2 mM CaCl(2). The Km and Vmax values for phosphatidyl choline were 0.95 mM and 810 micromol min(-1) mg(-1), respectively. More importantly, PLD(St) could not catalyze transphosphatidylation of glycerol, L-serine, myo-inositol and ethanolamine, which have been extensively used to evaluate the activity. The result strongly suggests that PLD( St ) does not have the transphosphatidylation activity, thereby making it the first Streptomyces PLD possessing only hydrolytic activity. PLD(St) may therefore be a novel type of PLD enzyme.


Subject(s)
Calcium Chloride/chemistry , Phospholipase D/chemistry , Phospholipase D/isolation & purification , Phospholipase D/metabolism , Streptomyces/enzymology , Electrophoresis, Polyacrylamide Gel , Enzyme Stability , Hydrogen-Ion Concentration , Hydrolysis , Kinetics , Molecular Weight , Phosphatidylcholines/chemistry , Temperature
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