Human Ileocecal Adenocarcinoma Research Articles

A Pumpless and Tubeless Microfluidic Device Enables Extended In Vitro Development of Cryptosporidium parvum.

The enteric parasite Cryptosporidium remains a treatment challenge for drinking water utilities globally due to its resistance to chlorine disinfection. However, the lack of an in vitro culture system for Cryptosporidium that is both cost-effective and reliable remains a key bottleneck in Cryptosporidium research. Here we report that the microfluidic culture of human ileocecal colorectal adenocarcinoma (HCT-8) cells under fluid shear stress enables the extended development of Cryptosporidium parvum. Specifically, the growth of C. parvum in a user-friendly pumpless microfluidic device was assessed using immunofluorescence assays, scanning electron microscopy, and quantitative polymerase chain reaction, which revealed that development continued for 10 days in total. Oocysts produced within the microfluidic device were infective to fresh HCT-8 monolayers; however, these oocysts were only present at low levels. We anticipate that such microfluidic approaches will facilitate a wide range of in vitro studies on Cryptosporidium and may have the potential to be further developed as a routine infectivity assessment tool for the water industry.

In vitro molecular assessment of Cryptosporidium parvum parasitic load on human ileocecal adenocarcinoma cell culture after targeting by tavaborole (AN2690)

In vitro molecular assessment of Cryptosporidium parvum parasitic load on human ileocecal adenocarcinoma cell culture after targeting by tavaborole (AN2690)

Screening and verification of outer membrane proteins of Cronobacter sakazakii with potential adhesion capability to human ileocecal adenocarcinoma cells

Cronobacter sakazakii (C. sakazakii), a food-borne pathogen, can cause severe intestinal diseases, such as intestinal damage and necrotizing enterocolitis, and even death in neonates and infants through its adhesion to intestinal epithelium cells by protein-protein interaction and translocation across the intestinal barrier. Nevertheless, the mechanisms of adhesion, translocation, and pathogenesis remain unclear. This study aimed to screen and validate the outer membrane proteins of C. sakazakii capable of adhering to the surface of intestinal cells through biotinylated protein adhesion and LC-MS/MS identification. A total of 319 proteins were identified. Gene Ontology and KEGG analysis revealed significant enrichment of ligand proteins in metabolism-related processes and catalytic activity. The identified 37 outer membrane proteins and 41 proteins of unknown subcellular localization or function mainly enriched in five protein-protein interaction clusters. Ten of these outer membrane/unknown proteins were selected to test their roles on C. sakazakii adhesion and invasion of intestinal cells by silencing the encoding gene expression and nine of the ten proteins, Protein_26/30/34/38/42/98/104/194/282, were shown to be critical in this process. This study contributes to the understanding of proteins involved in the host adhesion process by C. sakazakii as well as the mechanisms for its translocation across the intestinal barrier.

Mass Spectrometry Imaging of In Vitro Cryptosporidium parvum-Infected Cells and Host Tissue.

Cryptosporidium parvum is a zoonotic-relevant parasite belonging to the phylum Alveolata (subphylum Apicomplexa). One of the most zoonotic-relevant etiologies of cryptosporidiosis is the species C. parvum, infecting humans, cattle and wildlife. C. parvum-infected intestinal mucosa as well as host cells infected in vitro have not yet been the subject of extensive biochemical investigation. Efficient treatment options or vaccines against cryptosporidiosis are currently not available. Human cryptosporidiosis is currently known as a neglected poverty-related disease (PRD), being potentially fatal in young children or immunocompromised patients. In this study, we used a combination of atmospheric pressure scanning microprobe matrix-assisted laser desorption/ionization (AP-SMALDI) mass spectrometry imaging (MSI) and liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to determine and locate molecular biomarkers in in vitro C. parvum-infected host cells as well as parasitized neonatal calf intestines. Sections of C. parvum-infected and non-infected host cell pellets and infected intestines were examined to determine potential biomarkers. Human ileocecal adenocarcinoma cells (HCT-8) were used as a suitable in vitro host cell system. More than a thousand different molecular signals were found in both positive- and negative-ion mode, which were significantly increased in C. parvum-infected material. A database search in combination with HPLC-MS/MS experiments was employed for the structural verification of markers. Our results demonstrate some overlap between the identified markers and data obtained from earlier studies on other apicomplexan parasites. Statistically relevant biomarkers were imaged in cell layers of C. parvum-infected and non-infected host cells with 5 µm pixel size and in bovine intestinal tissue with 10 µm pixel size. This allowed us to substantiate their relevance once again. Taken together, the present approach delivers novel metabolic insights on neglected cryptosporidiosis affecting mainly children in developing countries.

Pinostrobin from plants and propolis against human coronavirus HCoV-OC43 by modulating host AHR/CYP1A1 pathway and lipid metabolism

Coronaviruses, as enveloped positive-strand RNA viruses, manipulate host lipid compositions to enable robust viral replication. Temporal modulation of the host lipid metabolism is a potential novel strategy against coronaviruses. Here, the dihydroxyflavone pinostrobin (PSB) was identified through bioassay that inhibited the increment of human coronavirus OC43 (HCoV-OC43) in human ileocecal colorectal adenocarcinoma cells. Lipid metabolomic studies showed that PSB interfered with linoleic acid and arachidonic acid metabolism pathways. PSB significantly decreased the level of 12, 13- epoxyoctadecenoic (12, 13-EpOME) and increased the level of prostaglandin E2. Interestingly, exogenous supplement of 12, 13-EpOME in HCoV-OC43-infected cells significantly stimulated HCoV-OC43 virus replication. Transcriptomic analyses showed that PSB is a negative modulator of aryl hydrocarbon receptor (AHR)/cytochrome P450 (CYP) 1A1signaling pathway and its antiviral effects can be counteracted by supplement of FICZ, a well-known AHR agonist. Integrative analyses of metabolomic and transcriptomic indicated that PSB could affect linoleic acid and arachidonic acid metabolism axis through AHR/CYP1A1 pathway. These results highlight the importance of the AHR/CYP1A1 pathway and lipid metabolism in the anti-coronavirus activity of the bioflavonoid PSB.

Whole transcriptome analysis of HCT-8 cells infected by Cryptosporidium parvum

BackgroundCryptosporidium species are zoonotic protozoans that are important causes of diarrhoeal disease in both humans and animals. Non-coding RNAs (ncRNAs) play an important role in the innate immune defense against Cryptosporidium infection, but the underlying molecular mechanisms in the interaction between human ileocecal adenocarcinoma (HCT-8) cells and Cryptosporidium species have not been entirely revealed.MethodsThe expression profiles of messenger RNAs (mRNAs), long non-coding RNAs (lncRNAs), microRNAs (miRNAs) and circular RNAs (circRNAs) in the early phase of infection of HCT-8 cells with Cryptosporidium parvum and at 3 and 12 h post infection were analyzed using the RNA-sequencing technique. The biological functions of differentially expressed RNAs (dif-RNAs) were discovered through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. The targeting relationships between three ncRNAs and mRNAs were analyzed using bioinformatics methods, followed by building a competing endogenous RNA (ceRNA) regulatory network centered on miRNAs.ResultsAfter strictly filtering the raw data, our analysis revealed 393 dif-lncRNAs, 69 dif-miRNAs and 115 dif-mRNAs at 3 hpi, and 450 dif-lncRNAs, 129 dif-miRNAs, 117 dif-mRNAs and one dif-circRNA at 12 hpi. Of these, 94 dif-lncRNAs, 24 dif-miRNAs and 22 dif-mRNAs were detected at both post-infection time points. Eleven dif-lncRNAs, seven dif-miRNAs, eight dif-mRNAs and one circRNA were randomly selected and confirmed using the quantitative real-time PCR. Bioinformatics analyses showed that the dif-mRNAs were significantly enriched in nutritional absorption, metabolic processes and metabolism-related pathways, while the dif-lncRNAs were mainly involved in the pathways related to the infection and pathogenicity of C. parvum (e.g. tight junction protein) and immune-related pathways (e.g. cell adhesion molecules). In contrast, dif-miRNAs and dif-circRNA were significantly enriched in apoptosis and apoptosis-related pathways. Among the downregulated RNAs, the miRNAs has-miR-324-3p and hsa-miR-3127-5p appear to be crucial miRNAs which could negatively regulate circRNA, lncRNA and mRNA.ConclusionsThe whole transcriptome profiles of HCT-8 cells infected with C. parvum were obtained in this study. The results of the GO and KEGG pathway analyses suggest significant roles for these dif-RNAs during the course of C. parvum infection. A ceRNA regulation network containing miRNA at its center was constructed for the first time, with hsa-miR-324-3p and hsa-miR-3127-5p being the crucial miRNAs. These findings provide novel insights into the responses of human intestinal epithelial cells to C. parvum infection.Graphical

The Effect of Short-Chain Fatty Acids on Growth of Cryptosporidium parvum In Vitro.

In a previous study, we observed an increase in the severity of cryptosporidial infection corresponding to decreased levels of short-chain fatty acids (SCFAs). Therefore, we decided to examine the effect of SCFAs on Cryptosporidium growth in human ileocecal adenocarcinoma (HTC-8) cells. HTC-8 cells were infected with 1 × 105 C. parvum oocysts. After 48 h of incubation with selected SCFAs, cells were fixed and labeled with monoclonal antibody directed to all intracellular stages, and the number of parasites was quantitated using a fluorescent microscope. Acetate, butyrate, propionate and valproate significantly inhibited growth, with an EC50 between 4 and 10 mM. Additionally, when combined, butyrate, acetate and propionate showed increased efficacy. Butyrate also inhibited growth when incubated with sporozoites prior to infection of host cell monolayers. In addition, we looked at possible mechanisms of action of inhibition. A combination of C. parvum infection and butyrate treatment led to increases in apoptosis and certain inflammatory cytokines. We conclude that acetate, propionate and butyrate have direct inhibitory activities in host cells against C. parvum, and butyrate can also affect sporozoite infectivity directly. While not preventing infection, SCFAs may help in keeping the infection low or in check.

Effects of selected condensed tannins on Cryptosporidium parvum growth and proliferation in HCT-8 cell cultures

Infections with Cryptosporidium spp. constitute a substantial public health burden and are responsible for widespread production losses in cattle herds. Reducing disease and shedding of Cryptosporidium spp. oocysts is an important One Health goal. There are very few therapeutic options available to treat cryptosporidiosis. Interest in plant bioactive compounds to mitigate the spread of anthelmintic resistance in ruminants has led to investigation of these phytocompounds against other parasitic taxa. Condensed tannins (CTs) are plant secondary metabolites that have shown potential against nematodes in vitro and in vivo but their applicability to Cryptosporidium spp. is comparatively under-explored. Cryptosporidium parvum infected human ileocecal colorectal adenocarcinoma (HCT)-8 cell cultures were treated with escalating doses of highly purified and well-characterized CTs from five plant species, big trefoil (Lotus pedunculatus), black currant (Ribes nigrum), sainfoin (Onobrychis viciifolia), white clover (Trifolium repens) and grapeseed (Vitis vinifera) for 44 h. Quantitative-PCR (qPCR) analysis revealed that none of the CTs examined demonstrated inhibitory potential against the parasite. Substantial inhibition of C. parvum by paromomycin was observed in positive controls in all assays (76.94–90.72% inhibition), proving the validity of the assay. Despite the lack of inhibition, these results represent an important step towards identifying alternative treatment options against this parasite.

MiRNA Expression Profile in Ileocecal Adenocarcinoma Cells Infected with Cryptosporidium

Cryptosporidium spp. is an opportunistic protozoan transmitted by fecal-oral route via oocysts. The agent may cause severe infection especially in individuals with suppressed immune system, due to its intracellular location and ability to cause auto-infection. MicroRNAs (miRNAs) are non-translated endogenous RNA molecules with an average of 22 nucleotides in length that regulate the expression of genes involved in important biological functions such as proliferation, differentiation, apoptosis and immune response. Recent studies have focused on the role of miRNAs in pathogenesis of infectious diseases and their potential to be used as biomarkers. The aim of this study was to determine the miRNA profile of human ileocecal adenocarcinoma (HCT-8) cells at 24 hours of infection with Cryptosporidium spp. In the study, the HCT-8 cell line was infected with Cryptosporidium spp. that were isolated from infected human stool samples and RNA was isolated from the cells 24 hours after infection. After this process, cDNA synthesis was performed and the expression of 95 human miRNA profiles were investigated by polymerase chain reaction (PCR) method. Fold changes of expression were determined by comparison with Cryptosporidium spp. uninfected cell lines. Sequence information of miRNAs and their target genes were performed via TargetScanHuman7.1 and miRDB websites, while gene ontology (GO) pathways of target genes were analyzed with the mirPath v.3 program. It was detected that the expression of 10 miRNAs were upregulated and 11 of them were downregulated compared with the control group. It was observed that, this 21 differentially expressed miRNAs were mainly associated with apoptosis, mitotic cell cycle, and immune response. Hsa-miR-612, hsa-miR-6763-5p, hsa-miR-188-5p, hsa-miR-664b-3p, hsa-miR-210-3p, hsa-let-7e-5p hsa-let-7b-3p, hsa-miR-4787-3p, hsa-miR-548ab, hsa-miR-3714 and hsamiR-4803 were found to be associated with apoptosis; and hsa-miR-612, hsa-miR-664b-3p, hsa-miR210-3p, hsa-let-7e-5p, hsa-let-7b-3p, hsa-miR-548ab, and hsa-miR4803 were found to be associated with mitotic cell cycle. The balance of proliferation and apoptosis is very significant in the development of infection and cancer. It is thought that determination of the effect of miRNAs on proliferation-apoptosis balance could provide information related to the etiopathogenesis and prognosis of infections, and on the role of microorganisms in carcinogenesis. In this study, 12 differentially expressed miRNAs were found to be associated with immune response. This may emphasize the role of miRNAs in the prevention and treatment of infections. It was concluded that, miRNAs could be used in the diagnosis, treatment and prevention of infections with the determination of miRNA's role in the infection mechanism as a result of the increasing number of studies.

Octaarginine Improves the Efficacy of Nitazoxanide against Cryptosporidium parvum.

Cryptosporidiosis is an intestinal disease that affects a variety of hosts including animals and humans. Since no vaccines exist against the disease till date, drug treatment is the mainstay of disease control. Nitazoxanide (NTZ) is the only FDA-approved drug for the treatment of human cryptosporidiosis. However, its efficacy in immunocompromised people such as those with AIDS, in malnourished children, or those with concomitant cryptosporidiosis is limited. In the absence of effective drugs against cryptosporidiosis, improving the efficacy of existing drugs may offer an attractive alternative. In the present work, we have assessed the potential of the cell-penetrating peptide (CPP) octaarginine (R8) to increase the uptake of NTZ. Octaarginine (R8) was synthetically attached to NTZ in an enzymatically releasable manner and used to inhibit growth of Cryptosporidium parvum in an in vitro culture system using human ileocecal adenocarcinoma (HCT-8) cell line. We observed a significant concentration-dependent increase in drug efficacy. We conclude that coupling of octaarginine to NTZ is beneficial for drug activity and it represents an attractive strategy to widen the repertoire of anti-cryptosporidial therapeutics. Further investigations such as in vivo studies with the conjugate drug will help to further characterize this strategy for the treatment of cryptosporidiosis.

Capturing Coronaviruses: Comparison of Recovery Methods for Infectious Coronaviruses From Environmental Surfaces

The emergence of novel, zoonotic betacoronavirus, SARS‐CoV‐2, demands quantification of infectious virus rather than viral RNA to provide more accurate assessment of transmission risk for COVID‐19. To maximize investigator safety, similar in morphology and inactivation profile, human betacoronavirus OC43 (OC43) was used as a surrogate to refine infectious virus recovery methods for SARS‐CoV‐2, a biosafety level (BSL)‐3 pathogen. Using OC43 and SARS‐CoV‐2, we examined the ability of InnovaPrep Mano Surface Samplers (MANOs), made of hydrophobic, open‐cell polymeric foam, to recover virus from large stainless‐steel surfaces hypothesizing that they would outperform hydrophilic cellulose sponges (sponges), used for environmental sampling.In triplicate, 1.0 x 105 TCID50 of OC43 and SARS‐CoV‐2 were applied to the inner surface of a biological safety cabinet (BSC) within the literature or vendor specified optimal surface area, 1267.36 cm2 (MANO) and 100 cm2 (sponges). The areas were sampled with eluant presoaked MANOs and sponges, and samples aliquoted and stored at ‐80ºC until batch titration by indirect immunofluorescence TCID50 assay, using human ileocecal colorectal adenocarcinoma cells (HRT‐18 CCL‐244, ATCC) for OC43 samples and crystal violet detection‐based TCID50 using African green monkey kidney epithelial cells (VeroE6 CRL‐1586, ATCC) for SARS‐CoV‐2. Tested eluants were a beef extract buffer, pH 7 (BEB7), BEB7 with 0.05% Tween‐20 (BEB7/T) and (MANOs only) phosphate buffered saline with 0.05% Tween‐20 (PBS/T), the vendor default. Additionally, an expanded surface area (0.77m2 for MANOs, 300cm2 for sponges) was tested with OC43 as described above, except with 1.0x104 TCID50 inoculum.For OC43, recovery for MANOs with BEB7 was 2.66x105 TCID50 compared to PBS/T’s 4.40x104 TCID50. BEB7 MANOs had a higher average percent recovery (102%) than BEB7 sponges (84%). By one‐way ANOVA (α=0.05), MANO BEB7’s and BEB7/T’s average recovery percentages were significantly greater than PBS/T’s. Samples taken from the larger surface areas for both samplers were below the assay’s limits of detection for BEB7; however, OC43 eluted with BEB7/T from sponges was detectable (3.47x102 TCID50, 32% recovery). For SARS‐CoV‐2, MANO BEB7’s average recovery percentage (27%) was again shown to be significantly greater than PBS/T’s (0.38%). However, decreased recovery of infectious virus was seen across both tools and all eluants, perhaps indicating a difference between SARS‐CoV‐2 and OC43 for BEB7.Use of BEB7 improved OC43 and SARS‐CoV‐2 recovery from optimal surface areas with MANOs. Surprisingly, when the surface area was enlarged, all samples except those from BEB7/T sponges were below the limit of detection. This might be explained by additional eluant loss on the larger surface during mechanical recovery or virus inactivation due to desiccation from BSC airflow or other environmental factors. Similar factors might explain the SARS‐CoV‐2 results. Quantification by RT‐qPCR or flow virometry, and planned experiments in BSL‐3 agricultural space, where the room is primary containment, may provide further insights.

Determining the Stability of Human Betacoronavirus OC43 on Different Surfaces

Scientists continue to study SARS‐CoV‐2, the virus currently responsible for a worldwide pandemic, to determine the best methods to inactivate the virus on surfaces and reduce the risk of contact transmission. Its classification as a Biosafety Level (BSL) ‐3 pathogen complicates research since few facilities have the capacity for this level of containment. Human betacoronavirus OC43 (OC43) is a good surrogate for SARS‐CoV‐2 based on its genetic similarity and OC43’s BSL‐2 classification. Two industry specific surfaces were inoculated with OC43 and sampled at timepoints that reflect typical industry timelines for sanitation. The objective was to determine the stability of OC43 on typical meat facility surfaces.OC43 was propagated on human ileocecal colorectal adenocarcinoma cells (HRT‐18, ATCC CCL‐244). Infectious virus was quantified by indirect immunofluorescence TCID50 assays on HRT‐18 cells. Stainless steel grade 316 and polyethylene (poly top) coupons were inoculated with 100 ul of 2.51 x 106 TCID50/ml virus by pipette in a grid pattern at room temperature (20ºC) in an active biosafety cabinet in triplicate for each timepoint. Coupons were rinsed with 5 ml of sterile filtered beef extract buffer (BEB7), composed of Tris base, glycine, magnesium chloride, and beef extract pH adjusted to 7.0, at 0, 1, 4, 8, and 16 hours post inoculation (hpi). The collected rinsate was aliquoted and stored at ‐80ºC until the TCID50 assays were conducted in batch. The 16 hpi stainless steel samples were created at the time of the poly top experiment. The TCID50 assays were run in duplicate for each sample and TCID50/ml was calculated and averaged for each replicate. Percent recovery of infectious virus was determined for each timepoint.Virus was observed to have partially dried at 1 hpi and was completely dry at all following timepoints on both surfaces. Few infectious virions were lost between inoculation and 0 hpi collection from both surfaces. Mean percent recovery (MPR) of infectious OC43 from stainless steel and poly top at 0 hpi was 153% and 90%, respectively. At 1 hpi, the MPR from stainless steel was 65% while poly top was 123%. The variability of the assay explains these findings. Stainless steel and poly top had average recoveries of 60% and 25% at 4 hours, respectively. The lowest MPR for stainless steel was 17% at 8 hpi while the lowest MPR for poly top was 7% at 16 hpi. A higher MPR of 43% from stainless steel at 16 hpi reflects this timepoint being conducted on a different day.Infectious OC43 is still detectable on common meat facility surfaces several hours after inoculation, but our current knowledge of enveloped viruses asserts that they are inviable after drying. A maximum decrease of only 1 log TCID50 between inoculation and the 16 hpi samples means that a person could potentially be infected between cleanings if it is possible to transfer dried infectious virus from a surface to a mucous membrane. However, this is a conjecture that requires further study since the infectious dose of SARS‐CoV‐2 is unknown and no experiment to determine if this contact transfer is possible has been conducted. Currently, similar experiments with SARS are underway.

High-Throughput Screening of a Marine Compound Library Identifies Anti-Cryptosporidium Activity of Leiodolide A.

Cryptosporidium sp. are apicomplexan parasites that cause significant morbidity and possible mortality in humans and valuable livestock. There are no drugs on the market that are effective in the population most severely affected by this parasite. This study is the first high-throughput screen for potent anti-Cryptosporidium natural products sourced from a unique marine compound library. The Harbor Branch Oceanographic Institute at Florida Atlantic University has a collection of diverse marine organisms some of which have been subjected to medium pressure liquid chromatography to create an enriched fraction library. Numerous active compounds have been discovered from this library, but it has not been tested against Cryptosporidium parvum. A high-throughput in vitro growth inhibition assay was used to test 3764 fractions in the library, leading to the identification of 23 fractions that potently inhibited the growth of Cryptosporidium parvum. Bioassay guided fractionation of active fractions from a deep-sea sponge, Leiodermatium sp., resulted in the purification of leiodolide A, the major active compound in the organism. Leiodolide A displayed specific anti-Cryptosporidium activity at a half maximal effective concentration of 103.5 nM with selectivity indexes (SI) of 45.1, 11.9, 19.6 and 14.3 for human ileocecal colorectal adenocarcinoma cells (HCT-8), human hepatocellular carcinoma cells (Hep G2), human neuroblastoma cells (SH-SY5Y) and green monkey kidney cells (Vero), respectively. The unique structure of leiodolide A provides a valuable drug scaffold on which to develop new anti-Cryptosporidium compounds and supports the importance of screening natural product libraries for new chemical scaffolds.

Mammalian Cell-Based Immunoassay for Detection of Viable Bacterial Pathogens.

Rapid detection of live pathogens is of paramount importance to ensure food safety. At present, nucleic acid-based polymerase chain reaction and antibody-based lateral flow assays are the primary methods of choice for rapid detection, but these are prone to interference from inhibitors, and resident microbes. Moreover, the positive results may neither assure virulence potential nor viability of the analyte. In contrast, the mammalian cell-based assay detects pathogen interaction with the host cells and is responsive to only live pathogens, but the short shelf-life of the mammalian cells is the major impediment for its widespread application. An innovative approach to prolong the shelf-life of mammalian cells by using formalin was undertaken. Formalin (4% formaldehyde)-fixed human ileocecal adenocarcinoma cell line, HCT-8 on 24-well tissue culture plates was used for the capture of viable pathogens while an antibody was used for specific detection. The specificity of the Mammalian Cell-based ImmunoAssay (MaCIA) was validated with Salmonella enterica serovar Enteritidis and Typhimurium as model pathogens and further confirmed against a panel of 15 S. Enteritidis strains, 8 S. Typhimurium, 11 other Salmonella serovars, and 14 non-Salmonella spp. The total detection time (sample-to-result) of MaCIA with artificially inoculated ground chicken, eggs, milk, and cake mix at 1–10 CFU/25 g was 16–21 h using a traditional enrichment set up but the detection time was shortened to 10–12 h using direct on-cell (MaCIA) enrichment. Formalin-fixed stable cell monolayers in MaCIA provide longer shelf-life (at least 14 weeks) for possible point-of-need deployment and multi-sample testing on a single plate.

Cryptosporidium parvum upregulates miR-942-5p expression in HCT-8 cells via TLR2/TLR4-NF-\u03baB signaling

BackgroundMicro (mi)RNAs are small noncoding RNA molecules that function in RNA silencing and post-transcriptional regulation of gene expression. This study investigated host miRNA activity in the innate immune response to Cryptosporidium parvum infection.MethodsIn vitro infection model adopts HCT-8 human ileocecal adenocarcinoma cells infected with C. parvum. The expression of miR-942-5p was estimated using quantitative real-time polymerase chain reaction (qPCR). The TLRs-NF-κB signaling was confirmed by qPCR, western blotting, TLR4- and TLR2-specific short-interfering (si)RNA, and NF-κB inhibition.ResultsHCT-8 cells express all known toll-like receptors (TLRs). Cryptosporidium parvum infection of cultured HCT-8 cells upregulated TLR2 and TLR4, and downstream TLR effectors, including NF-κB and suppressed IκBα (nuclear factor of kappa light polypeptide gene enhancer in B cells inhibitor, alpha). The expression of miR-942-5p was significantly upregulated at 4, 8, 12 and 24 h post-infection, and especially at 8 hpi. The results of TLR4- and TLR2-specific siRNA and NF-κB inhibition showed that upregulation of miR-942-5p was promoted by p65 subunit-dependent TLR2/TLR4-NF-κB pathway signaling.ConclusionsmiR-942-5p of HCT-8 cells was significantly upregulated after C. parvum infection, especially at 8 hpi, in response to a p65-dependent TLR2/TLR4-NF-κB signaling. TLR4 appeared to play a dominant role.

Flaxleaf Fleabane Leaves (Conyza bonariensis), A New Functional Nonconventional Edible Plant?

This work aimed to investigate the phytochemical composition, nutritional value, antioxidant, antihemolytic, antihyperglycemic, and antiproliferative activities of flaxleaf fleabane (Conyza bonariensis) leaves. Different concentrations of water and ethanol (0:100, 25:75, 50:50, 75:25, and 100:0 v/v) were used in the extraction process and results showed that the hydroalcoholic extract (50:50 v/v) presented the highest total phenolics, ortho-diphenolics, Folin-Ciocalteu reducing capacity, FRAP, and Fe2+ chelating ability values. Flaxleaf fleabane leaves (FFL) contained 19.6g/100g of fibers and 26g/100g of proteins. Ellagic acid, procyanidin A2, caffeic, rosmarinic, gallic, and 2,5-dihydroxybenzoic acids were the main phenolics. This phenolic-rich extract inhibited the lipid oxidation of Wistar rat brain (IC50 = 863.0mg GAE/L), inhibited α-glucosidase activity (IC50 = 435.4µg/mL), protected human erythrocytes against mechanical hemolysis at different osmolarity conditions, and showed cytotoxic/antiproliferative effects against human ileocecal adenocarcinoma cells (HCT8; IC50 = 552.6µg/mL) but no cytotoxicity toward noncancerous human lung fibroblast (IMR90). Overall, FFL showed potential to be explored by food companies to be a source of proteins, natural color substances, and phenolic compounds. PRACTICAL APPLICATION: Flaxleaf fleabane leaves (FFL) are usually burnt or partially given to cattle, without a proper utilization as a source of nutrients for human nutrition. Here, we studied the nutritional composition, phenolic composition, and toxicological aspects of FFL using different biological protocols. FFL was proven to be a rich source of proteins and dietary fibers and showed antioxidant activity measured by chemical and in vitro biological assays. Additionally, as it did protected human red cells and did not show cytotoxicity, we assume FFL has relative safety to be consumed as a nonconventional edible plant.

High-Content Screening for Cryptosporidium Drug Discovery.

High-content screening (HCS) is a cell-based type of phenotypic screening that combines multiple simultaneous readouts with a high level of throughput. A particular benefit of this form of screening for drug discovery is the ability to perform the interrogation in a biologically relevant system. This approach has greatly advanced the field of drug discovery for cryptosporidiosis, a diarrheal disease caused by protozoan parasites of Cryptosporidium spp. These parasites are obligate intracellular parasites and cannot be cultured in vitro without the support of a host cell, limiting the options for potential assay readout. Here we describe an established 384- or 1536-well format high-content imaging (HCI) assay of Cryptosporidium-infected HCT-8 human ileocecal adenocarcinoma cells. This HCS assay is a powerful tool to assess large numbers of compounds to power drug discovery, as well as to phenotypically characterize known Cryptosporidium-active compounds.

Synthesis, characterization, anti-tumor activity, photo-luminescence and BHb/HHb/Hsp90 molecular docking of zinc(II) hydroxyl-terpyridine complexes

Six zinc(II) complexes [Zn(Br)2L1] (1), [Zn(Br)2L2] (2) and [Zn(Br)2L3] (3), [Zn(I)2L1] (4), [Zn(I)2L2] (5) and [Zn(I)2L3] (6) have been obtained by the reactions of ZnBr2 or ZnI2 with p-hydroxyl-4′-phenyl-terpyridine(L1), m-hydroxyl-4′-phenyl-terpyridine(L2) and o-hydroxyl-4′-phenyl-terpyridine(L3), which were characterized by elemental analysis, FT-IR and NMR, as well as single crystal X-ray diffraction. Comparing to cisplatin, compounds 1–6 show higher antiproliferative activity against human lung carcinoma cell line (A549), human ileocecal colorectal adenocarcinoma cell line (HCT-8) and human breast cancer cell line (MCF-7). As the concentration of compounds 1–6 increases in the BHb/HHb-compound system, the fluorescent intensity of bovine hemoglobin (BHb) and human hemoglobin (HHb) reduces with a static quenching mechanism. The binding constant and the number of binding sites for the interaction of the compounds with BHb and HHb were calculated. Molecular docking studies suggest that the binding process of these compounds with heat shock protein 90 (Hsp90), BHb and HHb is a spontaneous molecular interaction process, in which van der Waals forces and hydrogen bonds play major roles, and π-π interaction also has influence on binding process. These results suggest that compounds 1–6 can be candidates for further evaluation as chemotherapeutic agents against human tumor.

3-acetyl-11-keto-beta-boswellic acid decreases the malignancy of taxol resistant human ovarian cancer by inhibiting multidrug resistance (MDR) proteins function

ObjectiveRecurrence of ovarian cancer is mainly due to multidrug resistance (MDR). 3-acetyl-11-keto-beta-boswellic acid (AKBA) could reverse the multidrug resistance in human ileocecal adenocarcinoma cells, but whether AKBA could modulate acquired MDR in ovarian cancer needs to be elucidated. MethodsThe current study examined the effect of AKBA on ovarian cancer MDR using a Taxol resistant human ovarian cancer cell line A2780/Taxol. Cell proliferation, migration and invasion, the intracellular accumulation of Rhodamine 123 and expression of MDR proteins were studiedin vitro. Furthermore, the effect of AKBA on oncogenicity of A2780/Taxol cells in nude mice xenograft model was studied. ResultsThe results showed that apart from its cytostatic and apoptosis-induction effect, AKBA could restrain A2780/Taxol cell migration and invasion. In addition, AKBA improved the sensitivity of A2780/Taxol cells to Taxol apparently, and the reversal of MDR by AKBA was evident by increasing intracellular Rhodamine 123 in cells. Furthermore, the anti-cancer potential of AKBA was evidenced as that AKBA treatment significantly slowed tumor growth and decreased the expression of P-gp, LRP, BCRP and MRP. ConclusionAbove results indicated that AKBA might be a potential compound to reverse MDR in human ovarian cancer.

Differential Responses of Colorectal Cancer Cell Lines to Enterococcus faecalis' Strains Isolated from Healthy Donors and Colorectal Cancer Patients.

The metabolites produced by the host’s gut microbiota have an important role in the maintenance of intestinal homeostasis, but can also act as toxins and induce DNA damage in colorectal epithelial cells increasing the colorectal cancer (CRC) chance. In this scenario, the impact of some of the components of the natural human gastrointestinal microbiota, such as Enterococcus faecalis (E. faecalis), at the onset of CRC progression remains controversial. Since under dysbiotic conditions it could turn into a pathogen, the aim of this study was to compare the effect of E. faecalis’ strains (isolated from CRC patients and healthy subjects’ stools) on the proliferation of different colorectal cells lines. First, we isolated and genotyping characterized the Enterococcus faecalis’ strains. Then, we analyzed the proliferation index (by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay) of three tumor and one normal intestinal cell lines, previously exposed to E. faecalis strains pre-cultured medium. Stool samples of CRC patients demonstrated a reduced frequency of E. faecalis compared to healthy subjects. In addition, the secreted metabolites of E. faecalis’ strains, isolated from healthy donors, decreased the human ileocecal adenocarcinoma cell line HCT-8 and human colon carcinoma cell line HCT-116 cell proliferation without effects on human colorectal adenocarcinoma cell line SW620 and on normal human diploid cell line CLR-1790. Notably, the metabolites of the strains isolated from CRC patients did not influence the cell growth of CRC cell lines. Our results demonstrated a new point of view in the investigation of E. faecalis’ role in CRC development, which raises awareness of the importance of not only associating the presence/absence of a unique microorganism, but also in defining the specific characteristics of the different investigated strains.