State of the Art: The Immunomodulatory Role of MSCs for Osteoarthritis

Osteoarthritis (OA) has generally been introduced as a degenerative disease; however, it has recently been understood as a low-grade chronic inflammatory process that could promote symptoms and accelerate the progression of OA. Current treatment strategies, including corticosteroid injections, have no impact on the OA disease progression. Mesenchymal stem cells (MSCs) based therapy seem to be in the spotlight as a disease-modifying treatment because this strategy provides enlarged anti-inflammatory and chondroprotective effects. Currently, bone marrow, adipose derived, synovium-derived, and Wharton’s jelly-derived MSCs are the most widely used types of MSCs in the cartilage engineering. MSCs exert immunomodulatory, immunosuppressive, antiapoptotic, and chondrogenic effects mainly by paracrine effect. Because MSCs disappear from the tissue quickly after administration, recently, MSCs-derived exosomes received the focus for the next-generation treatment strategy for OA. MSCs-derived exosomes contain a variety of miRNAs. Exosomal miRNAs have a critical role in cartilage regeneration by immunomodulatory function such as promoting chondrocyte proliferation, matrix secretion, and subsiding inflammation. In the future, a personalized exosome can be packaged with ideal miRNA and proteins for chondrogenesis by enriching techniques. In addition, the target specific exosomes could be a gamechanger for OA. However, we should consider the off-target side effects due to multiple gene targets of miRNA.     

Transcriptional Profiling of Whisker Follicles and of the Striatum in Methamphetamine Self-Administered Rats

Methamphetamine (MA) use disorder is a chronic neuropsychiatric disease characterized by recurrent binge episodes, intervals of abstinence, and relapses to MA use. Therefore, identification of the key genes and pathways involved is important for improving the diagnosis and treatment of this disorder. In this study, high-throughput RNA sequencing was performed to find the key genes and examine the comparability of gene expression between whisker follicles and the striatum of rats following MA self-administration. A total of 253 and 87 differentially expressed genes (DEGs) were identified in whisker follicles and the striatum, respectively. Multivariate and network analyses were performed on these DEGs to find hub genes and key pathways within the constructed network. A total of 129 and 49 genes were finally selected from the DEG sets of whisker follicles and of the striatum. Statistically significant DEGs were found to belong to the classes of genes involved in nicotine addiction, cocaine addiction, and amphetamine addiction in the striatum as well as in Parkinson’s, Huntington’s, and Alzheimer’s diseases in whisker follicles. Of note, several genes and pathways including retrograde endocannabinoid signaling and the synaptic vesicle cycle pathway were common between the two tissues. Therefore, this study provides the first data on gene expression levels in whisker follicles and in the striatum in relation to MA reward and thereby may accelerate the research on the whisker follicle as an alternative source of biomarkers for the diagnosis of MA use disorder.     

Genetic Diversity and Association Analysis for Carotenoid Content among Sprouts of Cowpea (Vigna unguiculata L. Walp)

The development and promotion of biofortified foods plants are a sustainable strategy for supplying essential micronutrients for human health and nutrition. We set out to identify quantitative trait loci (QTL) associated with carotenoid content in cowpea sprouts. The contents of carotenoids, including lutein, zeaxanthin, and β-carotene in sprouts of 125 accessions were quantified via high-performance liquid chromatography. Significant variation existed in the profiles of the different carotenoids. Lutein was the most abundant (58 ± 12.8 mg/100 g), followed by zeaxanthin (14.7 ± 3.1 mg/100 g) and β-carotene (13.2 ± 2.9 mg/100 g). A strong positive correlation was observed among the carotenoid compounds (r ≥ 0.87), indicating they can be improved concurrently. The accessions were distributed into three groups, following their carotenoid profiles, with accession C044 having the highest sprout carotenoid content in a single cluster. A total of 3120 genome-wide SNPs were tested for association analysis, which revealed that carotenoid biosynthesis in cowpea sprouts is a polygenic trait controlled by genes with additive and dominance effects. Seven loci were significantly associated with the variation in carotenoid content. The evidence of variation in carotenoid content and genomic regions controlling the trait creates an avenue for breeding cowpea varieties with enhanced sprouts carotenoid content.     

Polyphasic characterization of two microbial consortia with wide dechlorination spectra for chlorophenols

Two soil-free anaerobic dechlorinating cultures (3-CP and 35-DCP) were enriched from a pentachlorophenol (PCP)-to-phenol dechlorinating soil-dependent culture, using 3-chlorophenol (3-CP) and 3,5-dichlorophenol (3,5-DCP) as specific respective substrates, and characterized polyphasically. Physiological characterization indicated that the 3-CP and 35-DCP cultures had similar features, but with some variations. Both cultures utilized formate or acetate preferably as optimum electron donors for reductive dechlorination, and they shared similar patterns of dechlorination spectra for chlorophenols ranging from mono-CPs to a tetra-CP, with preferred dechlorination pathways in the ortho and meta positions. Alternative electron acceptors such as NO(3)(-) but not SO(4)(2-) inhibited the dechlorination activity in both cultures, while amorphous iron oxides (FeOOH) suppressed dechlorination activity only in the 35-DCP culture. Complete inhibition of dechlorination was observed in both cultures supplemented with chloramphenicol and vancomycin. The addition of 2-bromoethanesulfonate resulted in delayed dechlorination activity in the 35-DCP culture but not in the 3-CP culture; molybdate did not exert any inhibitory effect in either culture. Phylogenetic analysis based on 16S rRNA genes confirmed that the two cultures exhibited similar bacterial species but with varied responsible dechlorinators. Dehalobacter spp. were the likely dechlorinators in the 3-CP culture versus Sulfurospirillum spp. in the 35-DCP culture, with Clostridium and Clostridium-like spp. as candidate dechlorinators in both cultures.     

Purification of novel anti-inflammatory peptides from enzymatic hydrolysate of the edible microalgal Spirulina maxima

Natural bioactive peptides have been known as ingredients in nutraceuticals and pharmaceuticals. In this study, the potential anti-inflammatory peptides were purified from enzymatic hydrolysate of the edible microalgae Spirulina maxima using gastrointestinal endopeptidases (trypsin, α-chymotrypsin, and pepsin). Purification of the hydrolysate resulted in two peptides with amino acid sequences of LDAVNR (P1, 686 Da) and MMLDF (P2, 655 Da). It was found that peptides P1 and P2 exhibited significant inhibition on the release and production of histamine from antigen-stimulated RBL-2H3 mast cells. Moreover, the suppressive effect of P1 and P2 on production as well as expression of interleukin-8 in histamine-stimulated EA.hy926 endothelial cells was determined. Notably, the production of intracellular reactive oxygen species from mast cells and endothelial cells was decreased in the presence of P1 or P2. Collectively, the peptides P1 and P2 from S. maxima could be used as functional ingredients with potent anti-inflammatory benefits.     

Biochemical characterisation of a glycogen branching enzyme from Streptococcus mutans: Enzymatic modification of starch

A gene encoding a putative glycogen branching enzyme (SmGBE) in Streptococcus mutans was expressed in Escherichia coli and purified. The biochemical properties of the purified enzyme were examined relative to its branching specificity for amylose and starch. The activity of the approximately 75 kDa enzyme was optimal at pH 5.0, and stable up to 40 °C. The enzyme predominantly transferred short maltooligosyl chains with a degree of polymerization (dp) of 6 and 7 throughout the branching process for amylose. When incubated with rice starch, the enzyme modified its optimal branch chain-length from dp 12 to 6 with large reductions in the longer chains, and simultaneously increased its branching points. The results indicate that SmGBE can make a modified starch with much shorter branches and a more branched structure than to native starch. In addition, starch retrogradation due to low temperature storage was significantly retarded along with the enzyme reaction.     

Microbial removal of Fe(III) impurities from clay using dissimilatory iron reducers

Fe(III) impurities, which detract refractoriness and whiteness from porcelain and pottery, could be biologically removed from low-quality clay by indigenous dissimilatory Fe(III)-reducing microorganisms. Insoluble Fe(III) in clay particles was leached out as soluble Fe(II), and the Fe(III) reduction reaction was coupled to the oxidation of sugars such as glucose, maltose and sucrose. A maximum removal of 44-45% was obtained when the relative amount of sugar was 5% (w/w; sugar/clay). By the microbial treatment, the whiteness of the clay was increased from 63.20 to 79.64, whereas the redness was clearly decreased from 13.47 to 3.55.     

Factors affecting production of extracellular carbohydrate complexes by Escherichia coli O157:H7

Production of extracellular carbohydrate complexes (ECC) by foodborne pathogens on raw fruits and vegetables may result in protection against removal or inactivation by sanitizers. The influence of environmental conditions on cell growth, the total amount of ECC produced, and the amount of ECC produced on a per cell basis by Escherichia coli O157:H7 strains ATCC 43895 (wild type) and 43895-exopolysaccharides (EPS) (natural mutant, extensive EPS producer) was studied. To determine the effects of pH on the production of ECC on a per cell basis, E. coli O157:H7 was grown aerobically at 12 and 22 degrees C on tryptic soy agar (TSA) acidified to pH 7.0, 6.5, 6.0, 5.5, 5.0, 4.5, and 4.0. Lettuce, alfalfa sprout, cantaloupe, tomato, and apple juice agars (pH 4.46-6.50) were also evaluated for their support of the ECC production. Conditions generally favorable for growth of E. coli O157:H7 were a rich nutrient medium (TSA) vs. heated lettuce juice agar (HLJA) or minimal salts medium (MSM), 22 degrees C compared to 12 degrees C, and an aerobic atmosphere compared to modified atmosphere (1% O(2), 10% CO(2), and 89% N(2)). Conditions favorable for production of ECC on a per cell basis were HLJA, 12 degrees C, and an aerobic atmosphere. This suggests that modified atmosphere packaging of lettuce may not only decrease the growth of E. coli O157:H7 but also its propensity to form biofilm. There was a negative relationship between cell growth and production of ECC on a per cell basis, and environmental conditions that affected the total amount of ECC produced based on initial population reflected a combination of environmental conditions influencing both cell growth and ECC production on a per cell basis. A relative growth index factor (RGIF) was calculated to better understand ECC production as affected by various environmental conditions simultaneously. The production of ECC on a per cell basis by strain 43895-EPS showed a negative linear relationship with pH of TSA at both 12 and 22 degrees C. This strain generally produced a greater amount of ECC on fresh juice agar than on TSA at the same pH, but production of ECC on alfalfa sprout juice agar (FJA, pH 6.45) at 22 degrees C was significantly less than on TSA (pH 6.50). This indicates that nutrient limitation is not based only on nutrient availability. There may be other factors that repress the production of ECC on FJA, and the effects of those factors may be temperature dependent. Further studies will be required to better understand the relationship between nutrient availability and other factors on the production of ECC by E. coli O157:H7 on raw produce.