Production Of Degrading Enzymes Research Articles

Regarding on the Fractional Mathematical Model of Tumour Invasion and Metastasis

In this paper, we analyze the behaviour of solution for the system exemplifying model of tumour invasion and metastasis by the help of q-homotopy analysis transform method (q-HATM) with the fractional operator. The analyzed model consists of a system of three nonlinear differential equations elucidating the activation and the migratory response of the degradation of the matrix, tumour cells and production of degradative enzymes by the tumour cells. The considered method is graceful amalgamations of q-homotopy analysis technique with Laplace transform (LT), and Caputo–Fabrizio (CF) fractional operator is hired in the present study. By using the fixed point theory, existence and uniqueness are demonstrated. To validate and present the effectiveness of the considered algorithm, we analyzed the considered system in terms of fractional order with time and space. The error analysis of the considered scheme is illustrated. The variations with small change time with respect to achieved results are effectively captured in plots. The obtained results confirm that the considered method is very efficient and highly methodical to analyze the behaviors of the system of fractional order differential equations.

Solid state fermentation for poly (L-lactide)-degrading enzyme production by Laceyella sacchari LP175 in aerated tray reactor and its hydrolysis of poly (lactide) polymer

Solid state fermentation for poly (L-lactide)-degrading enzyme production by Laceyella sacchari LP175 in aerated tray reactor and its hydrolysis of poly (lactide) polymer

Matrix protease production, epithelial-to-mesenchymal transition marker expression and invasion of glioblastoma cells in response to osmotic or hydrostatic pressure

Both hydrostatic and osmotic pressures are altered in the tumour microenvironment. Glioblastoma (GBM) is a brain tumour with high invasiveness and poor prognosis. We hypothesized that physical and osmotic forces regulate glioblastoma (GBM) invasiveness. The osmotic pressure of GBM cell culture medium was adjusted using sodium chloride or water. Alternatively, cells were subjected to increased hydrostatic force. The proteolytic profile and epithelial–mesenchymal transition (EMT) were investigated using zymography and real-time qPCR. The EMT markers assessed were Snail-1, Snail-2, N-cadherin, Twist and vimentin. Invasion was investigated in vitro using extracellular matrix-coated Transwell inserts. In response to osmotic and mechanical pressure, GBM cell lines U87 and U251 and patient-derived neural oncospheres upregulated the expression of urokinase-type plasminogen activator (uPA) and/or matrix metalloproteinases (MMPs) as well as some of the EMT markers tested. The adherent cell lines invaded more when placed in media of increased osmolality. Therefore, GBM respond to osmotic or mechanical pressure by increasing matrix degrading enzyme production, and adopting a phenotype reminiscent of EMT. Better understanding the molecular and cellular mechanisms by which increased pressure promotes GBM invasiveness may help to develop innovative therapeutic approaches.

Actinobacteria as Promising Candidate for Polylactic Acid Type Bioplastic Degradation.

Polylactic acid (PLA) is one of the most commercially available and exploited bioplastics worldwide. It is an important renewable polymer for the replacement of petroleum-based plastic materials. They are both biodegradable and bio-based plastic. Microbial degrading activity is a desirable method for environmental safety and economic value for bioplastic waste managements. Members of the phylum actinobacteria are found to play an important role in PLA degradation. Most of the PLA degrading actinobacteria belong to the family Pseudonocardiaceae. Other taxa include members of the family Micromonosporaceae, Streptomycetaceae, Streptosporangiaceae, and Thermomonosporaceae. This mini-review aims to provide an overview on PLA degrading actinobacteria including their diversity and taxonomy, isolation and screening procedures and PLA degrading enzyme production from 1997 to 2019. Consideration is also given to where to sampling and how we might use these beneficial actinobacteria for PLA waste management.

Promotion of the growth and plant biomass degrading enzymes production in solid-state cultures of Lentinula edodes expressing Vitreoscilla hemoglobin gene

Vitreoscilla hemoglobin (VHb), encoded by the Vitreoscilla hemoglobin gene (vgb), is highly effective at binding oxygen and delivering it to both prokaryotes and eukaryotes under hypoxic conditions. In this study, we introduced the vgb gene into shiitake mushrooms, and the mycelia of the transformatants grew faster. In particular, they spread into the solid substrate located in the lower part of the test tubes and bags where the oxygen was hypoxic and produced more β-glucan and plant biomass degrading enzymes compared to the original strain. The maximum growth rate of the transformants was 8.5%–15.9% higher than that of the original strain on sawdust-based cultures in plastic bags. The laccase and amylase activities were 17.7%–40.3% and 16.7%–37.9% higher than that of the original strain, respectively. In addition, the β-glucan contents of the transformant mycelia from the submerged fermentation were 12.9%–24.0% higher than that of the original strain. These results reveal that the expression of VHb in mushroom fungi promots the mycelial growth in solid-state cultures under the hypoxic condition as well as enhances β-glucan and plant biomass degrading enzymes production.

Evaluation of antagonistic activities against Pythium myriotylum and plant growth promoting traits of Streptomyces isolated from Cocoyam (Xanthosoma sagittifolium (L.) Schott) rhizosphere

The focus of this study was to isolate, evaluate and characterize cocoyam rhizospheric actinobacteria collected from Mount Cameroon for their potential antagonistic activities against Pythium myriotylum, the causative agent of cocoyam root rot disease, and/or their ability to promote plant growth. Actinobacteria were isolated from soil samples by using serial dilution method. Dual culture assay was used to screen the isolates against fungal phytopathogens including P. myriotylum. The selected isolates were characterized morphologically, physiologically, biochemically and genetically. Furthermore, these isolates were subjected to in vitro production of various plant growth promoting (PGP) traits. Among the 287 isolates distributed into 12 distinct groups, PFK4, PFBOT7 and PFEL2 had high antagonistic effects against P. myriotylum and they were regarded as promising candidates for further study of their biocontrol ability. The identification of actinobacterial isolates was done using universal PCR of partial 16S rRNA sequences combined with bioinformatics and phylogenetic procedures. The results revealed that all these isolates belong to the genus Streptomyces spp. The isolate PFK4 showed 99% similarity with Streptomyces albulus while PFBOT7 showed 99% similarity with Streptomyces albus and PFEL2 showed 98% similarity with Streptomyces gandoceansis based on their 16S rRNA gene sequences. In this study for the first time, we report S. gandocaensis strain for the biological control of Pythium myriotylum. The role of these isolates in Plant Growth Promotion (PGP) by in vitro production of PGP traits such as phosphate solubilisation, siderophore, indole-3-acetic acid (IAA), ACC deaminase and cell wall degrading enzymes production were also evaluated and showed as potential PGP agents. Concurrent production of PGP substances coupled with broad spectrum of antifungal and antibacterial activities of these three strains suggest their potential use as promising biocontrol and PGP tools for the development of an alternative control method for cocoyam cultivation.

XIST/miR-376c-5p/OPN axis modulates the influence of proinflammatory M1 macrophages on osteoarthritis chondrocyte apoptosis.

The inflammatory microenvironment in the joints is one of the critical issues during osteoarthritis (OA) and also the main factor that may aggravate symptoms. Under inflammatory microenvironment, M1 macrophages are activated and produce large numbers of proinflammatory mediators, leading to the production of degradative enzymes, the disturbance of chondrocyte apoptosis and cartilage catabolic processes, and finally the deterioration of OA. In the present study, we reveal that the overexpression of osteopontin (OPN), a cytokine, and a matrix protein involved in arthritis and chondrocyte apoptosis in OA, could exacerbate the inflammatory microenvironment in OA via promoting the production of proinflammation cytokines and the levels of degradative enzymes in M1 macrophages, therefore, enhancing the cytotoxicity of M1 macrophage on chondrocytes. XIST expression significantly increases in OA tissue specimens. XIST serves as a competing endogenous RNA for miR-376c-5p to compete with OPN for miR-376c-5p binding, thus counteracting miR-376c-5p-mediated OPN suppression. XIST knockdown could improve the inflammatory microenvironment in OA via acting on M1 macrophages, subsequently affecting the apoptosis of cocultured chondrocytes. miR-376c-5p inhibition exerts an opposing effect on M1 macrophages and cocultured chondrocytes, as well as significantly reverses the effect of XIST knockdown. As a further confirmation, XIST and OPN mRNA expression significantly increased in OA tissues and was positively correlated in tissue samples. In summary, we provide a novel mechanism of macrophages and the inflammatory microenvironment affecting chondrocyte apoptosis. XIST and OPN might be potential targets for OA treatment, which needs further in vivo experimental confirmation.

Modulation of the Wnt pathway through inhibition of CLK2 and DYRK1A by lorecivivint as a novel, potentially disease-modifying approach for knee osteoarthritis treatment

Wnt pathway upregulation contributes to knee osteoarthritis (OA) through osteoblast differentiation, increased catabolic enzymes, and inflammation. The small-molecule Wnt pathway inhibitor, lorecivivint (SM04690), which previously demonstrated chondrogenesis and cartilage protection in an animal OA model, was evaluated to elucidate its mechanism of action. Biochemical assays measured kinase activity. Western blots measured protein phosphorylation in human mesenchymal stem cells (hMSCs), chondrocytes, and synovial fibroblasts. siRNA knockdown effects in hMSCs and BEAS-2B cells on Wnt pathway, chondrogenic genes, and LPS-induced inflammatory cytokines was measured by qPCR. Invivo anti-inflammation, pain, and function were evaluated following single intra-articular (IA) lorecivivint or vehicle injection in the monosodium iodoacetate (MIA)-induced rat OA model. Lorecivivint inhibited intranuclear kinases CDC-like kinase 2 (CLK2) and dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A). Lorecivivint inhibited CLK2-mediated phosphorylation of serine/arginine-rich (SR) splicing factors and DYRK1A-mediated phosphorylation of SIRT1 and FOXO1. siRNA knockdowns identified a role for CLK2 and DYRK1A in Wnt pathway modulation without affecting β-catenin with CLK2 inhibition inducing early chondrogenesis and DYRK1A inhibition enhancing mature chondrocyte function. NF-κB and STAT3 inhibition by lorecivivint reduced inflammation. DYRK1A knockdown was sufficient for anti-inflammatory effects, while combined DYRK1A/CLK2 knockdown enhanced this effect. In the MIA model, lorecivivint inhibited production of inflammatory cytokines and cartilage degradative enzymes, resulting in increased joint cartilage, decreased pain, and improved weight-bearing function. Lorecivivint inhibition of CLK2 and DYRK1A suggested a novel mechanism for Wnt pathway inhibition, enhancing chondrogenesis, chondrocyte function, and anti-inflammation. Lorecivivint shows potential to modify structure and improve symptoms of knee OA.

Cartilage Wear Particles Induce an Inflammatory Response Similar to Cytokines in Human Fibroblast-Like Synoviocytes.

The synovium plays a key role in the development of osteoarthritis, as evidenced by pathological changes to the tissue observed in both early and late stages of the disease. One such change is the attachment of cartilage wear particles to the synovial intima. While this phenomenon has been well observed clinically, little is known of the biological effects that such particles have on resident cells in the synovium. The present work investigates the hypothesis that cartilage wear particles elicit a pro-inflammatory response in diseased and healthy human fibroblast-like synoviocytes, like that induced by key cytokines in osteoarthritis. Fibroblast-like synoviocytes from 15 osteoarthritic human donors and a subset of three non-osteoarthritic donors were exposed to cartilage wear particles, interleukin-1α or tumor necrosis factor-α for 6 days and analyzed for proliferation, matrix production, and release of pro-inflammatory mediators and degradative enzymes. Wear particles significantly increased proliferation and release of nitric oxide, interleukin-6 and -8, and matrix metalloproteinase-9, -10, and -13 in osteoarthritic synoviocytes, mirroring the effects of both cytokines, with similar trends in non-osteoarthritic cells. These results suggest that cartilage wear particles are a relevant physical factor in the osteoarthritic environment, perpetuating the pro-inflammatory and pro-degradative cascade by modulating synoviocyte behavior at early and late stages of the disease. Future work points to therapeutic strategies for slowing disease progression that target cell-particle interactions. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1979-1987, 2019.

FSTL1 Promotes Inflammatory Reaction and Cartilage Catabolism through Interplay with NFκB Signaling Pathways in an In Vitro ONFH Model.

Osteonecrosis of the femoral head (ONFH) usually occurs in young people and is closely associated with autoimmune reactions. Follistatin-like 1 (FSTL1) was recently proven to participate in several inflammation-related diseases. The role of FSTL1 in ONFH is still unclear. Serum levels of FSTL1 were not significantly different in ONFH patients and healthy individuals. In contrast, elevated expression levels of FSTL1 were observed in degraded cartilage and synovial fluid in ONFH patients and in a cultured human primary chondrocyte model treated with interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α). Suppression of FSTL1 by FSTL1-siRNA downregulated the inflammatory response mediated by IL-1β or TNF-α in cultured human chondrocytes. In a human cartilage culture model, FSTL1 promoted the production of inflammatory cytokines and cartilage degradation enzymes. The activation of NFκB signaling pathway was detected in degenerated cartilage from ONFH patients and in FSTL1-treated chondrocytes. Additionally, administration of an NFκB inhibitor (JSH-23) significantly reduced the overexpression of inflammatory cytokines and protein degradation enzymes induced by FSTL1 and maintained the level of major cartilage matrix components (aggrecan and collagen II). In summary, FSTL1 was involved in the degeneration progression of the ONFH and might provide a novel direction for treating and curing ONFH.

Assessment of environmental gene tags linked with carbohydrate metabolism and chemolithotrophy associated microbial community in River Ganga

The microbial community mediated biogeochemical cycles play important role in global C-cycle and display a sensitive response to environmental changes. Limited information is available on microbial composition and functional diversity controlling biogeochemical cycles in the riverine environment. The Ganga River water and sediment samples were studied for environmental gene tags with reference to carbohydrate metabolism, photoheterotrophy and chemolithotrophy using high throughput shotgun metagenomic sequencing and functional annotation. The diversity of environmental gene tags specific microbial community was annotated against reference sequence database using Kaiju taxonomic classifier. The metagenomic analyses revealed that the river harbored a broad range of carbohydrate and energy metabolism genes. The in-depth investigation of metagenomic data revealed that the enzymes associated with reverse TCA cycle, Calvin-Benson cycle enzyme RuBisCO, starch and sucrose metabolism genes were highly abundant. The enzymes associated with sulfur metabolism such as EC:2.7.7.4 (sulfate to ammonium per sulfate), EC:1.8.1.2, EC:1.8.7.1 (sulfite to H2S) were prevalent in both the class of samples. The principal component analysis of the functional profiles revealed that the water and sediment samples were clustered distinctly suggesting that both the sites had variable abundance of functional genes and associated microbiota. The taxonomic classification showed abundance of Proteobacteria, Actinobacteria and Bacteroidetes phyla. Also, the metagenomic study showed the presence of purple sulfur bacteria viz. Thiodictyon, Nitrosococcus and purple non-sulfur bacteria viz. Bradyrhozobium and Rhodobacter. The study demonstrates that the Ganga River microbiome has prevalence of functional genes involved in carbohydrate anabolism and catabolism, and CO2 fixation with great prospects in cellulose and sulfide degrading enzyme production and characterization.

Structural and molecular changes in the menisci of experimental models of post-traumatic osteoarthritis

Purpose: Meniscal pathology is commonly associated with anterior cruciate ligament (ACL) injuries and substantially increases the risk of osteoarthritis (OA) developing later in life. The mechanisms driving meniscal degeneration after an ACL injury and its subsequent role in osteoarthritis pathogenesis are not clearly defined. The aim of this study was to investigate the structural and molecular progression of meniscal pathology in two mouse models of ACL injury with known differences in OA outcomes: surgical ACL transection (ACLT) and mechanical ACL rupture (ACLR). Methods: ACL injury was induced in the right hindlimb of 10-week-old, male C57BL/6 mice by either surgical transection (ACLT) or mechanical compression (ACLR). Separate un-injured mice and sham-surgery controls were included for comparison. At 1, 2, 4 and 8 weeks post-injury, joints were harvested for histology (n=7) or isolation of the medial and lateral menisci for gene expression (n=5 for ACLT/ACLR; n=2 for un-injured/sham using pooled samples of 3). The medial and lateral menisci were evaluated separately for both outcome measures. Meniscal pathology was assessed histologically using semi-quantitative scores for: proteoglycan loss, structural damage and peripheral bone formation. Quantitative PCR was performed to investigate key molecules implicated in meniscal and wider joint pathology. Results: Meniscal pathology was evident both medially and laterally following ACL injury. Superficial proteoglycan loss was notable from 1 week post-injury, particularly in the medial meniscus. Structural damage was more rapid and severe in the medial meniscus of ACLR joints compared with ACLT but lateral pathology was similar between the two groups. Peripheral bone formation was similarly elevated in the medial meniscus of ACLR joints but no different between the two groups at 8 weeks post-injury. Molecular meniscal changes were generally greater in the medial versus lateral meniscus. Acan, Col2a1, Col10a1, Mmp9, and Mmp13 were all significantly upregulated after ACL injury but were not notably different between the two models. Acan and Col2a1 increases preceded maximal meniscal pathology, while Col10a1, Mmp9, and Mmp13 were found to increase more gradually over time in both ACL injury models. Other genes (Col1a1, Adamts4, Mmp2, Lox, IGF, Il1b) were similarly regulated in all joints exposed to an intervention (ACL-injured and sham joints). Conclusions: The temporo-spatial development of meniscal pathology in the two ACL-injury models mirrored their known differences in OA onset and progression (ACLR-OA develops more rapidly than ACLT-OA). Both ACL injury models induced specific meniscal molecular changes with a greater increase in the medial meniscus compared to the lateral. These changes may be predictive of long term meniscal pathology and have the potential to contribute to the development of medial tibiofemoral OA though reduced mechanical function and increased production of degradative enzymes.

Poly(l-lactide)-Degrading Enzyme Production by Laceyella sacchari LP175 Under Solid State Fermentation Using Low Cost Agricultural Crops and Its Hydrolysis of Poly(l-lactide) Film

The aim of this study was to investigate the enhancement of poly(l-lactide) (PLLA)-degrading enzyme production by Laceyella sacchari LP175 under solid state fermentation (SSF) using low-cost agricultural crops as substrates and its hydrolysis of poly(l-lactide) film. Cassava chip, soybean meal and corncob were used to investigate the enzyme production using a statistical mixture design method. The effect of various inducers and SSF growth conditions parameters affecting PLLA-degrading enzyme production were also investigated. The fermentation of solid substrates was up-scale in a static tray bioreactor. The crude enzyme extracted from the fermented solid substrate was used to evaluate the biological degradation of PLLA film at 50 °C for 24 h. The results of substrate combination showed that 5 g of the substrate mixture, consisting of 4.3 g cassava chips and 0.7 g soybean meal, yielded 320 U/g dry solid. The addition of 0.1 g peptone to the mixture of solid materials increased enzyme production up to 456 U/g dry solid. The production of enzyme in a static tray bioreactor with optimized physical conditions yielded the maximum enzyme production, 472 U/g dry solid. The 20 mL reaction consisting of 8600 mg/L PLLA film was degraded by the crude enzyme extracted from the fermented solid substrate. Agricultural crops and wastes contain significant amounts of nutrients for microbial growth and products. This is the first reported of PLLA degrading enzyme production under SSF using low-cost substrates showing the possibility for application in large-scale biological recycling of bio-plastic as a future sustainable process.

Nutrient Competition Mediated Antagonism of Microbes Against Rhizoctonia solani

Plant growth-promoting (PGP) microorganisms are beneficial soil micro creatures which may facilitate plant growth by direct or indirect ways. Bacillus amyloliquefaciens MB101 (BA), Streptomyces atrovirens N23 (SA) and Hypocrea lixii NAIMCC-F-01760 (HL) were earlier reported to have the ability to manage the tomato root rot disease caused by Rhizoctonia solani (RS) at some extent. In the present study, effect of nutrient supplementation like potato dextrose broth (PDB) and tomato root extract (TRE) on antagonism of these three microbes was characterized under the soil microcosm in order to understand the role of nutrient in microbe-microbe interaction. A moderate influence on the population of all three antagonists was resulted by PDB and TRE with RS. However, TRE and PDB were causing a significant impact on cell wall degrading enzymes and antifungal activity in the presence of RS. Moreover, hyphal degradation of RS was proved by scanning electron micrographs in the absence of substrates. Nutrient competition enhanced the call wall degrading enzyme production. Therefore, the present study concluded the role of substrate in the mycoparasitism and also sustain the potential of the hereby methodology (soil microcosm) for screening of other soil-inhibiting organism in the future.

Hfq, a RNA Chaperone, Contributes to Virulence by Regulating Plant Cell Wall-Degrading Enzyme Production, Type VI Secretion System Expression, Bacterial Competition, and Suppressing Host Defense Response in Pectobacterium carotovorum.

Hfq is a RNA chaperone and participates in a wide range of cellular processes and pathways. In this study, mutation of hfq gene from Pectobacterium carotovorum subsp. carotovorum PccS1 led to significantly reduced virulence and plant cell wall-degrading enzyme (PCWDE) activities. In addition, the mutant exhibited decreased biofilm formation and motility and greatly attenuated carbapenem production as well as secretion of hemolysin coregulated protein (Hcp) as compared with wild-type strain PccS1. Moreover, a higher level of callose deposition was induced in Nicotiana benthamiana leaves when infiltrated with the mutant. A total of 26 small (s)RNA deletion mutants were obtained among a predicted 27 sRNAs, and three mutants exhibited reduced virulence in the host plant. These results suggest that hfq plays a key role in Pectobacterium virulence by positively impacting PCWDE production, secretion of the type VI secretion system, bacterial competition, and suppression of host plant responses.

Association of interleukin 1 gene polymorphism with intervertebral disc degeneration risk in the Chinese Han population.

Intervertebral disc degeneration (IDD) is a major pathological process implicated in low back pain and is a prerequisite to disk herniation. Interleukin-1 α (IL-1α) was thought to be involved in the pathogenesis of disc degeneration by increasing the production of extracellular matrix degradation enzymes and by inhibiting extracellular matrix synthesis. IL-1α may provide insight about the etiology of IDD. We performed a hospital-based case–control study involving 200 IDD patients and 200 controls in the Chinese Han population. Genotyping was performed using a custom-by-design 48-Plex single nucleotide polymorphism Scan™ Kit. Our study indicated that IL-1α -899C/T polymorphism could increase the risk of IDD under the homozygous, recessive, and allelic models. Subsequently, we validated this significant association by a meta-analysis. Stratification analysis of ethnicity in this meta-analysis also obtained a significant association among Asians and Caucasians. In conclusion, the present study finds that IL-1α -899C/T polymorphism is associated with the risk of IDD. Larger studies with more diverse ethnic populations are needed to confirm these results.

Screening and Identification of Trichoderma Strains Isolated from Natural Habitats with Potential to Cellulose and Xylan Degrading Enzymes Production.

A total of 123 Trichoderma strains were isolated from different habitats and tested for their ability to degrade cellulose and xylan by simple plate screening method. Among strains, more than 34 and 45% respectively, exhibited higher cellulolytic and xylanolytic activity, compared to the reference strain T. reesei QM 9414. For strains efficiently degrading cellulose, a highest enzyme activity was confirmed using filter paper test, and it resulted in a range from 1.01 to 7.15 FPU/ml. Based on morphological and molecular analysis, the isolates were identified as Trichoderma. The most frequently identified strains belonged to Trichoderma harzianum species. Among all strains, the most effective in degradation of cellulose and xylose was T. harzianum and T. virens, especially those isolated from forest wood, forest soil or garden and mushroom compost. The results of this work confirmed that numerous strains from the Trichoderma species have high cellulose and xylan degradation potential and could be useful for lignocellulose biomass conversion e.g. for biofuel production.

Characterization of the structure, cells, and cellular mechanobiological response of human plantar fascia

In this study, we report that human plantar fascia consists of two distinct tissues with differential structural properties. These tissues also contain stem/progenitor cells with differential biological properties. The mechanobiological responses of these two plantar fascia stem cells also differ in terms of expression of collagen I and IV, non-ligament-related genes, and proinflammatory genes. The production of inflammatory agents (prostaglandin E2, interleukin-6) and matrix degradative enzymes (matrix metalloproteinase-1, matrix metalloproteinase-2) are also different between the two types of plantar fascia stem cells. Based on the findings from this study, we suggest that plantar fasciitis results from the aberrant mechanobiological responses of the stem cells from plantar fascia sheath and core tissues. Our findings may also be used to devise tissue engineering approaches to treat plantar fascia injury effectively.

Gingival Tissue Inflammation Promotes Increased Matrix Metalloproteinase-12 Production by CD200Rlow Monocyte-Derived Cells in Periodontitis.

Irreversible tissue recession in chronic inflammatory diseases is associated with dysregulated immune activation and production of tissue degradative enzymes. In this study, we identified elevated levels of matrix metalloproteinase (MMP)-12 in gingival tissue of patients with the chronic inflammatory disease periodontitis (PD). The source of MMP12 was cells of monocyte origin as determined by the expression of CD14, CD68, and CD64. These MMP12-producing cells showed reduced surface levels of the coinhibitory molecule CD200R. Similarly, establishing a multicellular three-dimensional model of human oral mucosa with induced inflammation promoted MMP12 production and reduced CD200R surface expression by monocyte-derived cells. MMP12 production by monocyte-derived cells was induced by CSF2 rather than the cyclooxygenase-2 pathway, and treatment of monocyte-derived cells with a CD200R ligand reduced CSF2-induced MMP12 production. Further, MMP12-mediated degradation of the extracellular matrix proteins tropoelastin and fibronectin in the tissue model coincided with a loss of Ki-67, a protein strictly associated with cell proliferation. Reduced amounts of tropoelastin were confirmed in gingival tissue from PD patients. Thus, this novel association of the CD200/CD200R pathway with MMP12 production by monocyte-derived cells may play a key role in PD progression and will be important to take into consideration in the development of future strategies to diagnose, treat, and prevent PD.

The DNA-methyltransferase inhibitor 5-aza-2-deoxycytidine affects Humicola grisea enzyme activities and the glucose-mediated gene repression.

Humicola grisea var. thermoidea (Hgvt) is a thermophilic ascomycete that produces lignocellulolytic enzymes and it is proposed for the conversion of agricultural residues into useful byproducts. Drugs that inhibit the DNA methyltransferases (DNMTs) activity are employed in epigenetic studies but nothing is known about a possible effect on the production of fungal enzymes. We evaluated the effect of 5-aza-2'-deoxycytidine (5-Aza; a chemical inhibitor of DNMTs activity) on the secreted enzyme activity and on the transcription of cellulase and xylanase genes from Hgvt grown in agricultural residues and in glucose. Upon cultivation on wheat bran (WB), the drug provoked an increase in the xylanase activity at 96 h. When Hgvt was grown in glucose (GLU), a repressor of Hgvt glycosyl hydrolase genes, 5-Aza led to increased transcript accumulation for the cellobiohydrolases and for the xyn2 xylanase genes. In WB, 5-Aza enhanced the expression of the transcription factor CreA gene. Growth on WB or GLU, in presence of 5-Aza, led to a significant increase in transcripts of the pH-response regulator PacC gene. To our knowledge, this is the first report on the effect of a DNMT inhibitor in the production of fungal plant cell wall degradation enzymes.