Biological evaluation of 5-fluorouracil nanoparticles for cancer chemotherapy and its dependence on the carrier, PLGA

Nanoscaled devices have great potential for drug delivery applications due to their small size. In the present study, we report for the first time the preparation and evaluation of antitumor efficacy of 5-fluorouracil (5-FU)-entrapped poly (D, L-lactic-co-glycolic acid) (PLGA) nanoparticles with dependence on the lactide/glycolide combination of PLGA. 5-FU-loaded PLGA nanoparticles with two different monomer combinations, 50-50 and 90-10 were synthesized using a modified double emulsion method, and their biological evaluation was done in glioma (U87MG) and breast adenocarcinoma (MCF7) cell lines. 5-FU-entrapped PLGA 50-50 nanoparticles showed smaller size with a high encapsulation efficiency of 66%, which was equivalent to that of PLGA 90-10 nanoparticles. Physicochemical characterization of nanoparticles using differential scanning calorimetry and X-ray diffraction suggested the presence of 5-FU in molecular dispersion form. In vitro release studies showed the prolonged and sustained release of 5-FU from nanoparticles with both the PLGA combinations, where PLGA 50-50 nanoparticles showed faster release. Nanoparticles with PLGA 50-50 combination exhibited better cytotoxicity than free drug in a dose- and time-dependent manner against both the tumor cell lines. The enhanced efficiency of PLGA 50-50 nanoparticles to induce apoptosis was indicated by acridine orange/ethidium bromide staining. Cell cycle perturbations studied using flow cytometer showed better S-phase arrest by nanoparticles in comparison with free 5-FU. All the results indicate that PLGA 50-50 nanoparticles possess better antitumor efficacy than PLGA 90-10 nanoparticles and free 5-FU. Since, studies have shown that long-term exposure of ailing tissues to moderate drug concentrations is more favorable than regular administration of higher concentration of the drug; our results clearly indicate the potential of 5-FU-loaded PLGA nanoparticles with dependence on carrier combination as controlled release formulation to multiplex the therapeutic effect of cancer chemotherapy

Fermentation, Isolation, Structure, and antidiabetic activity of NFAT-133 produced by Streptomyces strain PM0324667

Type-2 diabetes is mediated by defects in either insulin secretion or insulin action. In an effort to identify extracts that may stimulate glucose uptake, similar to insulin, a high throughput-screening assay for measuring glucose uptake in skeletal muscle cells was established. During the screening studies to discover novel antidiabetic compounds from microbial resources a Streptomyces strain PM0324667 (MTCC 5543, the Strain accession number at Institute of Microbial Technology, Chandigarh, India), an isolate from arid soil was identified which expressed a secondary metabolite that induced glucose uptake in L6 skeletal muscle cells. By employing bioactivity guided fractionation techniques, a tri-substituted simple aromatic compound with anti-diabetic potential was isolated. It was characterized based on MS and 2D NMR spectral data and identified as NFAT-133 which is a known immunosuppressive agent that inhibits NFAT-dependent transcription in vitro. Our investigations revealed the antidiabetic potential of NFAT-133. The compound induced glucose uptake in differentiated L6 myotubes with an EC50 of 6.3 ± 1.8 μM without activating the peroxisome proliferator-activated receptor-γ. Further, NFAT-133 was also efficacious in vivo in diabetic animals and reduced systemic glucose levels. Thus it is a potential lead compound which can be considered for development as a therapeutic for the treatment of type-2 diabetes. We have reported herewith the isolation of the producer microbe, fermentation, purification, in vitro, and in vivo antidiabetic activity of the compound

Transcriptomic signatures reveal immune dysregulation in human diabetic and idiopathic gastroparesis

Abstract Background Cellular changes described in human gastroparesis have revealed a role for immune dysregulation, however, a mechanistic understanding of human gastroparesis and the signaling pathways involved are still unclear. Methods Diabetic gastroparetics, diabetic non-gastroparetic controls, idiopathic gastroparetics and non-diabetic non-gastroparetic controls underwent full-thickness gastric body biopsies. Deep RNA sequencing was performed and pathway analysis of differentially expressed transcripts was done using Ingenuity®. A subset of differentially expressed genes in diabetic gastroparesis was validated in a separate cohort using QT-PCR. Results 111 genes were differentially expressed in diabetic gastroparesis and 181 in idiopathic gastroparesis with a log2fold difference of | ≥ 2| and false detection rate (FDR) < 5%. Top canonical pathways in diabetic gastroparesis included genes involved with macrophages, fibroblasts and endothelial cells in rheumatoid arthritis, osteoarthritis pathway and differential regulation of cytokine production in macrophages and T helper cells by IL-17A and IL-17F. Top canonical pathways in idiopathic gastroparesis included genes involved in granulocyte adhesion and diapedesis, agranulocyte adhesion and diapedesis, and role of macrophages, fibroblasts and endothelial cells in rheumatoid arthritis. Sixty-five differentially expressed genes (log2fold difference | ≥ 2|, FDR < 5%) were common in both diabetic and idiopathic gastroparesis with genes in the top 5 canonical pathways associated with immune signaling. 4/5 highly differentially expressed genes (SGK1, APOLD1, CXCR4, CXCL2, and FOS) in diabetic gastroparesis were validated in a separate cohort of patients using RT-PCR. Immune profile analysis revealed that genes associated with M1 (pro inflammatory) macrophages were enriched in tissues from idiopathic gastroparesis tissues compared to controls (p < 0.05). Conclusions Diabetic and idiopathic gastroparesis have both unique and overlapping transcriptomic signatures. Innate immune signaling likely plays a central role in pathogenesis of human gastroparesis.https://deepblue.lib.umich.edu/bitstream/2027.42/145193/1/12920_2018_Article_379.pd

Transcriptomic signatures reveal immune dysregulation in human diabetic and idiopathic gastroparesis

Abstract Background Cellular changes described in human gastroparesis have revealed a role for immune dysregulation, however, a mechanistic understanding of human gastroparesis and the signaling pathways involved are still unclear. Methods Diabetic gastroparetics, diabetic non-gastroparetic controls, idiopathic gastroparetics and non-diabetic non-gastroparetic controls underwent full-thickness gastric body biopsies. Deep RNA sequencing was performed and pathway analysis of differentially expressed transcripts was done using Ingenuity®. A subset of differentially expressed genes in diabetic gastroparesis was validated in a separate cohort using QT-PCR. Results 111 genes were differentially expressed in diabetic gastroparesis and 181 in idiopathic gastroparesis with a log2fold difference of | ≥ 2| and false detection rate (FDR) < 5%. Top canonical pathways in diabetic gastroparesis included genes involved with macrophages, fibroblasts and endothelial cells in rheumatoid arthritis, osteoarthritis pathway and differential regulation of cytokine production in macrophages and T helper cells by IL-17A and IL-17F. Top canonical pathways in idiopathic gastroparesis included genes involved in granulocyte adhesion and diapedesis, agranulocyte adhesion and diapedesis, and role of macrophages, fibroblasts and endothelial cells in rheumatoid arthritis. Sixty-five differentially expressed genes (log2fold difference | ≥ 2|, FDR < 5%) were common in both diabetic and idiopathic gastroparesis with genes in the top 5 canonical pathways associated with immune signaling. 4/5 highly differentially expressed genes (SGK1, APOLD1, CXCR4, CXCL2, and FOS) in diabetic gastroparesis were validated in a separate cohort of patients using RT-PCR. Immune profile analysis revealed that genes associated with M1 (pro inflammatory) macrophages were enriched in tissues from idiopathic gastroparesis tissues compared to controls (p < 0.05). Conclusions Diabetic and idiopathic gastroparesis have both unique and overlapping transcriptomic signatures. Innate immune signaling likely plays a central role in pathogenesis of human gastroparesis.https://deepblue.lib.umich.edu/bitstream/2027.42/145193/1/12920_2018_Article_379.pd

Endogenous antigen processing drives the primary CD4+ T cell response to influenza.

By convention, CD4+ T lymphocytes recognize foreign and self peptides derived from internalized antigens in combination with major histocompatibility complex class II molecules. Alternative pathways of epitope production have been identified, but their contributions to host defense have not been established. We show here in a mouse infection model that the CD4+ T cell response to influenza, critical for durable protection from the virus, is driven principally by unconventional processing of antigen synthesized within the infected antigen-presenting cell, not by classical processing of endocytosed virions or material from infected cells. Investigation of the cellular components involved, including the H2-M molecular chaperone, the proteasome and γ-interferon-inducible lysosomal thiol reductase revealed considerable heterogeneity in the generation of individual epitopes, an arrangement that ensures peptide diversity and broad CD4+ T cell engagement. These results could fundamentally revise strategies for rational vaccine design and may lead to key insights into the induction of autoimmune and anti-tumor responses

A candidate regulatory variant at the TREM gene cluster associates with decreased Alzheimer's disease risk and increased TREML1 and TREM2 brain gene expression

Introduction: We hypothesized that common Alzheimer's disease (AD)-associated variants within the triggering receptor expressed on myeloid (TREM) gene cluster influence disease through gene expression. Methods: Expression microarrays on temporal cortex and cerebellum from ∼400 neuropathologically diagnosed subjects and two independent RNAseq replication cohorts were used for expression quantitative trait locus analysis. Results: A variant within a DNase hypersensitive site 5′ of TREM2, rs9357347-C, associates with reduced AD risk and increased TREML1 and TREM2 levels (uncorrected P = 6.3 × 10−3 and 4.6 × 10−2, respectively). Meta-analysis on expression quantitative trait locus results from three independent data sets (n = 1006) confirmed these associations (uncorrected P = 3.4 × 10−2 and 3.5 × 10−3, Bonferroni-corrected P = 6.7 × 10−2 and 7.1 × 10−3, respectively). Discussion: Our findings point to rs9357347 as a functional regulatory variant that contributes to a protective effect observed at the TREM locus in the International Genomics of Alzheimer's Project genome-wide association study meta-analysis and suggest concomitant increase in TREML1 and TREM2 brain levels as a potential mechanism for protection from AD

Setting Implementation Research Priorities to Reduce Preterm Births and Stillbirths at the Community Level

Asha George and colleagues from the GAPPS group report the implementation research priorities to address prematurity and stillbirths at the community level that resulted from their recent expert consensus exercise