Proteolytic Genes Research Articles

An Update of the Promise of Glycine Supplementation for Enhancing Physical Performance and Recovery.

Glycine, the simple amino acid, is a key component of muscle metabolism with proven cytoprotective effects and hypothetical benefits as a therapeutic nutrient. Cell, in vitro, and animal studies suggest that glycine enhances protection against muscle wasting by activating anabolic pathways and inhibiting proteolytic gene expression. Some evidence indicates that glycine supplementation may enhance peak power output, reduce lactic acid accumulation during high-intensity exercise, and improve sleep quality and recovery. This literature review critically explores glycine's potential as an ergogenic aid and its relevance to muscle regeneration, muscle strength, endurance exercise performance, and sleep quality. It also underscores key areas for future research. It is concluded that more randomized controlled clinical trials in humans are needed to confirm glycine's potential as a dietary supplement to support muscle function, recovery, and overall athletic performance as an ergogenic aid and to establish nutritional recommendations for athletic performance. Also, it is essential to consider that high doses (>500 mg/kg of body mass) could induce cytotoxic effects and contribute to acute glutamate toxicity.

Characterizing the association of systemic estradiol levels and transcriptional markers of skeletal muscle regeneration in healthy young females

Recent research indicates estradiol's (E2) role in modulating skeletal muscle regeneration. E2 has been observed to enhance myogenic capacity by upregulating myogenic factors and downregulating proteolytic factors[1,2]. The extracellular matrix (ECM) of skeletal muscle also influences regeneration due to its interaction with muscle progenitor cells [5]. Cell and animal studies observed E2's ability to impact on collagen (COL) 1, 3, and 4 production [3,4]. However, limited data from physiologically relevant human models exploring myogenic markers and ECM throughout the menstrual cycle are available. We hypothesize that higher systemic E2 levels will correspond to an increased regenerative gene expression signature. Understanding this relationship is crucial for assessing how E2 levels affect muscle healing in eumenorrheic women and E2’s potential as a therapeutic molecule for enhancing muscle repair. The study included 19 pre-menopausal women aged 18-39 undergoing hip surgery at UT Southwestern (UTSW) Medical Center. This study was approved by the UTSW IRB and conducted in accordance with the Declaration of Helsinki. Blood and muscle biopsies were collected for hormone and gene analysis. Only subjects in the follicular phase (n=12) were included to minimize progesterone's influence. Investigated genes included myogenic factors (MYOD1, MYF5, MYF6, MYOG), proteolytic factors (FOXO3, MuRF1), and COL genes (COL1a1, COL-3a1, COL-4a1, COL-6a1). E2 levels ranged from 26-356 pg/mL, with negligible progesterone levels, consistent with the follicular phase. While no significant relationships were found between myogenic and proteolytic genes, MYF6 exhibited a positive relationship with E2 (p=0.07), while MuRF1 showed a negative one (p=0.09). COL 1, 3, and 6 gene expressions had no significant relationship with E2, but COL 4 exhibited a statistically significant positive relationship (p=0.04) with E2 concentration. Though no statistically significant relationships emerged between myogenic or proteolytic gene expression and E2 levels, there were notable trends toward significance for MYF6 and MuRF1. MYF6, recognized for its role in myogenic differentiation, is implicated in maintaining the satellite cell pool by promoting myokine secretion[6]. In contrast, MuRF1 is a critical component in muscle atrophy[7]. COL4 expression was significantly associated with E2 levels (p=0.4). It is hypothesized that COL4 enhances IGF1-activated myoblast migration, differentiation, and fusion [5]. These findings suggest a potential link between elevated E2 levels and an enhanced regenerative capacity. These findings indicate that higher E2 conditions may create a favorable environment for muscle recovery. Future research should increase sample size and examine protein levels of these factors.

Effects of Amino Acid Supplementation to a Low-Protein Diet on the Growth Performance and Protein Metabolism-related Factors in Broiler Chicks.

A low-protein (LP) diet may alleviate the environmental impact of chicken meat production by reducing nitrogen excretion and ammonia emissions. Thus, this study investigated the effect of a 15% reduced protein diet with or without amino acid (AA) supplementation on the growth performance of broiler chicks from 10 to 35 days of age and the underlying mechanism for loss of skeletal muscle mass. Thirty-six male broiler chicks were allocated to three experimental groups based on body weight: control, LP, and essential AA-supplemented LP (LP+AA). The body weight gain, feed conversion ratio, and weight of breast muscles and legs significantly decreased only in the LP group at the end of the feeding period. Plasma uric acid levels were significantly lower in the LP+AA group than those of the other groups. In the LP group, mRNA levels of microtubule-associated protein 1 light chain 3 isoform B were significantly higher in the pectoralis major, whereas those of atrogin-1, muscle RING-finger protein-1, and myoblast determination protein 1 were significantly higher in the biceps femoris compared to those in the control group. There were no significant differences in insulin-like growth factor 1 mRNA levels in the liver or skeletal muscle between groups. These findings suggested that supplementation with essential AAs ameliorated the impaired effects of an LP diet on growth performance in broiler chicks, and that the transcriptional changes in proteolytic genes in skeletal muscles might be related to the impaired effects of the LP diet.

MRNA expression profiles of proteolytic genes during the process of ovulation in ovarian follicles of sturgeons

mRNA expression profiles of proteolytic genes during the process of ovulation in ovarian follicles of sturgeons

Refined control of CRISPR-Cas9 gene editing in Clostridium sporogenes: the creation of recombinant strains for therapeutic applications.

Despite considerable clinical success, the potential of cancer immunotherapy is restricted by a lack of tumour-targeting strategies. Treatment requires systemic delivery of cytokines or antibodies at high levels to achieve clinically effective doses at malignant sites. This is exacerbated by poor penetration of tumour tissue by therapeutic antibodies. High-grade immune-related adverse events (irAEs) occur in a significant number of patients (5-15%, cancer- and therapeutic-dependent) that can lead to lifelong issues and can exclude from treatment patients with pre-existing autoimmune diseases. Tumour-homing bacteria, genetically engineered to produce therapeutics, is one of the approaches that seeks to mitigate these drawbacks. The ability of Clostridium sporogenes to form spores that are unable to germinate in the presence of oxygen (typical of healthy tissue) offers a unique advantage over other vectors. However, the limited utility of existing gene editing tools hinders the development of therapeutic strains. To overcome the limitations of previous systems, expression of the Cas9 protein and the gRNA was controlled using tetracycline inducible promoters. Furthermore, the components of the system were divided across two plasmids, improving the efficiency of cloning and conjugation. Genome integrated therapeutic genes were assayed biochemically and in cell-based functional assays. The potency of these strains was further improved through rationally-conceived gene knock-outs. The new system was validated by demonstrating the efficient addition and deletion of large sequences from the genome. This included the creation of recombinant strains expressing two pro-inflammatory cytokines, interleukin-2 (IL-2) and granulocyte macrophage-colony stimulating factor (GM-CSF), and a pro-drug converting enzyme (PCE). A comparative, temporal in vitro analysis of the integrant strains and their plasmid-based equivalents revealed a substantial reduction of cytokine activity in chromosome-based constructs. To compensate for this loss, a 7.6 kb operon of proteolytic genes was deleted from the genome. The resultant knock-out strains showed an 8- to 10-fold increase in cytokine activity compared to parental strains.

The independent effects of local heat application on muscle growth program associated mRNA and protein phosphorylation

The development and maintenance of skeletal muscle is crucial for the support of daily function. Recent evidence suggests that genes coded for proteins associated with the human muscle growth program (myogenic and proteolytic genes) are sensitive to local heat application. Therefore, the purpose of this investigation was to determine the effect of 4 h of local heat application to the vastus lateralis at rest on acute phosphorylation (mTORSer2448, p70-S6K1Thr389, and 4E-BP1Thr47/36) and gene expression changes for proteins associated with the muscle growth program. Intramuscular temperature of the HOT limb was 1.2 ± 0.2 °C higher than CON limb after 4 h of local heating. However, this local heat stimulus did not influence transcription of genes associated with myogenesis (MSTN, p = 0.321; MYF5, p = 0.445; MYF6, p = 0.895; MEF2a, p = 0.809; MYO-G, p = 0.766; MYO-D1, p = 0.118; RPS3, p = 0.321; and RPL-3L, p = 0.577), proteolysis (Atrogin-1, p = 0.573; FOXO3a, p = 0.452; MURF-1, p = 0.284), nor protein phosphorylation (mTORSer2448, p = 0.981; P70–S6K1Thr389, p = 0.583; 4E-BP1Thr37/46, p = 0.238) associated with the muscle growth program. These findings suggest little to no association between the local application of heat, at rest, and the activation of the observed muscle growth program-related markers.

Molecular and biotechnological characteristics of proteolytic activity from Streptococcus thermophilus as a proteolytic lactic acid bacteria to enhance protein-derived bioactive peptides.

The demand for healthy food items with a high nutrient value of bioavailability and bioaccessibility has created a need for continuous development of technology and food ingredients like bioactive peptides. This study aimed to investigate seven proteolytic lactic acid bacteria (PLABs) isolated from the plaa-som (fermented fish) sample originated from silver BARB species for production of proteolytic enzymes. Proteolytic enzymes produced by (PLABs) were used further to create potent bioactive peptides by hydrolyzing proteins throughout PLAB-probiotics enhancer. Protein derived-bioactive peptides was tested the proteolytic activity on different protein sources and examined bioactivities including antioxidative and antimicrobial effect for further use in functional foods. Results of screened-PLAB strains showed high proteolytic activity namely Streptococcus thermophilus strains (KKUPA22 and KKUPK13). These strains have proteolytic system consisting of extracellular and cell-bound enzymes that used for degrading protein in fish flesh protein (FFP) and skim milk (SKM) broth media. Proteolytic activity of tested bacterial enzymes was estimated after incubation at 45, 37, and 50 °C. Furthermore, FFP hydrolysates were formed with various peptides and has small molecular weights (checked by SDS-PAGE) in the range of10.5 to 22 kDa), exhibiting strong activity. Data revealed that S. thermophilus strains (KKUPA22 and KKUPK13) had high antioxidant activity in term of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) radical-scavenging inhibition, and ferric reducing antioxidant power (FRAP) reducing power capacity. Both strains (KKUPA22 and KKUPK13) of S. thermophilus have higher antimicrobial activity against Gram-negative bacteria than against Gram-positive bacteria. We have confirmed presence of proteolytic (prt) gene regions in S. thermophilus strains using specific primers via PCR amplification. Results showed highest homology (100%) with the prtS gene of S. thermophillus located on the cell envelope proteolytic enzymes (CEPEs) such as serine proteinase. Therefore, it concluded that the proteolytic system of tested PLAB strains able to generate bioactive peptides-derived proteins having active biological property, good mechanism of degradability, and bioaccessibility for further use in catalyzing protein of functional foods.

Влияние микрокапсулированных стартовых культур на образование биологически активных пептидов в готовых мясных продуктах

Of particular importance in the production of fermented meat products are starter cultures with a proteolytic system that promotes the proteolysis of the protein components of meat raw materials. Numerous compounds, which may have biological activity, were formed as a result of the proteolysis, for example, biologically active peptides or bacteriocins. Nevertheless, there are some technological difficulties in the use of bacteria that contribute to the formation of biologically active peptides in raw meat. The solution to this problem can be microencapsulation. In this study, industrially valuable strains of starter cultures were selected, and proteolytic activity genes were identified. Thus, the proteolytic genes of the PRTB10/PRTB20 and P15C/P06C families were found in the P. acidilactici 38 and P. pentosaceus 28 strains, while the genes of the Jp23/Jp25 and prti2/IP6Xba families were found in the L. acidophilus AT-45 strain. The prti2/IP6Xba genes were also found in the S. carnosus 111-2 strain. A technology is proposed for incorporating microorganisms into alginate capsules with an alginate gel concentration of 5%, which makes it possible to form strong capsules capable of maintaining the viability of starter cultures in the production of boiled sausage: when incubating heat-treated capsules to 72 °С on chalk agar, the survival rate of microorganisms from 30 to 90% was recorded. The protein profile of the samples of boiled sausages produced using microencapsulated starter cultures was studied. A significant interaction of some strains with proteins of the actomyosin complex was shown, and the enzymes of energy metabolism from muscle tissue were subjected to destructive changes - muscle creatine phosphate kinase, enolase, and adenylate kinase 1. The paper contains 4 Figures, 4 Tables, and 27 References. The Authors declare no conflict of interest.

Effects of dietary arginine on growth, activity of digestive enzymes, GCN2‐ATF4 signalling pathway and nutritional metabolism‐related gene expression of large yellow croaker ( Larimichthys crocea ) larvae

A 30-day feeding experiment was conducted to elucidate the effects of dietary arginine on growth performance, activity of digestive enzymes, GCN2-ATF4 signalling pathway and nutritional metabolism-related gene expression of large yellow croaker larvae (initial weight: 10.56 ± 0.26 mg). Four isonitrogenous and isolipidic diets with different arginine levels (19.5, 31.0, 39.6 and 48.6 g kg−1 of dry matter) were formulated. Results showed that no significant differences in survival, growth and whole-body proximate composition were observed among dietary treatments. The whole-body arginine content of fish larvae was significantly increased with increasing contents of dietary arginine, and the maximum was observed in larvae fed the diet with 48.6 g kg−1 arginine. However, the contents of other amino acids were not significantly affected. Larvae fed the diet with 19.5 g kg−1 arginine showed higher activity of alkaline phosphatase (AKP) in the intestinal segments (IS) and brush border membranes (BBM) than other groups. The expression of GCN2-ATF4 signalling pathway-related genes (atf4, chop and asns) in the visceral mass of larvae was significantly upregulated by dietary 39.6–48.6 g kg−1 arginine supplementation. Dietary 48.6 g kg−1 arginine significantly upregulated the expression of proteolytic genes (murf1 and glud) in the visceral mass of larvae. Furthermore, the highest expression of genes related to fatty acid β-oxidation (cpt1α) and glycolysis (gk and pk) was observed in the 39.6 g kg−1-arginine group. In summary, those results suggested that dietary arginine had no significant influence on the growth performance of large yellow croaker larvae. However, the arginine level significantly affected the arginine content of whole larvae, activity of digestive enzymes, lipid metabolism and glycolysis of larvae. The GCN2-ATF4 signalling pathway was stimulated by high-dose (31.0–48.6 g kg−1) arginine, maybe due to the antagonistic effect of arginine and lysine. These results might indicate that 19.5 g kg−1 dietary arginine (37.6 g kg−1 dietary protein) could meet the growth requirement of large yellow croaker larvae.

Diet and Exercise Modulate GH-IGFs Axis, Proteolytic Markers and Myogenic Regulatory Factors in Juveniles of Gilthead Sea Bream (Sparus aurata).

Simple SummaryThe effects of exercise and diet on growth markers were analyzed in gilthead sea bream juveniles. Under voluntary swimming, fish fed with a high-lipid diet showed lower growth, growth hormone (GH) plasma levels, flesh texture, and higher expression of main muscle proteolytic markers than those fed with a high-protein diet. However, under sustained exercise, most of the differences disappeared and fish growth was similar regardless of the diet, suggesting that exercise improves nutrients use allowing a reduction of the dietary protein, which results in an enhanced aquaculture production.The physiological and endocrine benefits of sustained exercise in fish were largely demonstrated, and this work examines how the swimming activity can modify the effects of two diets (high-protein, HP: 54% proteins, 15% lipids; high-energy, HE: 50% proteins, 20% lipids) on different growth performance markers in gilthead sea bream juveniles. After 6 weeks of experimentation, fish under voluntary swimming and fed with HP showed significantly higher circulating growth hormone (GH) levels and plasma GH/insulin-like growth-1 (IGF-1) ratio than fish fed with HE, but under exercise, differences disappeared. The transcriptional profile of the GH-IGFs axis molecules and myogenic regulatory factors in liver and muscle was barely affected by diet and swimming conditions. Under voluntary swimming, fish fed with HE showed significantly increased mRNA levels of capn1, capn2, capn3, capns1a, n3, and ub, decreased gene and protein expression of Ctsl and Mafbx and lower muscle texture than fish fed with HP. When fish were exposed to sustained exercise, diet-induced differences in proteases’ expression and muscle texture almost disappeared. Overall, these results suggest that exercise might be a useful tool to minimize nutrient imbalances and that proteolytic genes could be good markers of the culture conditions and dietary treatments in fish.

Enhanced Extracellular Matrix Breakdown Characterizes the Early Distraction Phase of Canine Knee Joint Distraction.

ObjectiveJoint distraction triggers intrinsic cartilage repair in animal models of osteoarthritis (OA), corroborating observations in human OA patients treated with joint distraction. The present study explores the still largely elusive mechanism initiating this repair process.DesignUnilateral OA was induced in the knee joint of 8 dogs using the groove model; the contralateral joint served as a control. After 10 weeks, 4 animals received joint distraction, the other 4 serving as OA controls. Halfway the distraction period (after 4 weeks of a standard 8-week distraction treatment), all animals were euthanized, and joint tissues were collected. A targeted quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis was performed of commonly involved processes including matrix catabolism/anabolism, inflammation, and known signaling pathways in OA. In addition, cartilage changes were determined on tissue sections using the canine OARSI (Osteoarthritis Research Society International) histopathology score and collagen type II (COL2A1) immunostaining.ResultsMidway distraction, the distracted OA joint showed an upregulation of proteolytic genes, for example, ADAMTS5, MMP9, MMP13, compared to OA alone and the healthy joints, which correlated with an increased OARSI score. Additionally, genes of the transforming growth factor (TGF)-β and Notch pathway, and markers associated with progenitor cells were increased.ConclusionsJoint distraction initiates both catabolic and anabolic transcriptional responses. The enhanced turnover, and thereby renewal of the matrix, could be the key to the cartilage repair observed in the months after joint distraction.

644 Bioprinted skin integrates into full-thickness porcine wounds and supports healthy skin repair by modulating inflammation and tissue remodeling

The purpose of this study is to assess the feasibility and efficacy of autologous bioprinted skin in the treatment of full-thickness porcine wounds. We hypothesize that bioprinted skin constructs will improve wound healing by modulating inflammation, skin remodeling, and epidermal maturation. Porcine keratinocytes, fibroblasts, pre-adipocytes, and endothelial cells were isolated, expanded, suspended in bioink, and bioprinted to form a biomimetic tri-layer skin construct. 5x5cm excisional full-thickness wounds were then treated with bioprinted skin from autologous or allogeneic cells, skin autograft or allograft, hydrogel, or left without treatment. Digital planimetry of photographs taken over 28 days demonstrated improved wound closure in autologous bioprinted skin treated wounds. Histological analysis confirmed these results and showed improved epidermal maturity, less fibrosis, and more normal collagen organization in the bioprinted autologous skin group. Hydrogel and skin allograft groups had increased total wound serum proteins and proteolytic activity, with an associated increase in inflammatory and proteolytic gene expression compared to the bioprinted autograft. These findings suggest that treatment of full-thickness porcine wounds with hydrogel generates inflammatory wound healing and protease activity. Alternatively, bioprinted constructs composed of autologous skin cells embedded in hydrogel induce healthy, pro-remodeling protease activity, resulting in normal wound healing. Taken together, our results suggest that bioprinted autologous skin rapidly integrates into the wound to support skin regeneration and confirms the feasibility of skin bioprinting technology for clinical treatment of full-thickness wounds in human patients.

Analysis of the proteolytic system of Streptococcus thermophilus strains CS5, CS9, CS18 and CS20

Streptococcus thermophilus is a common milk starter, and the ability to hydrolyse proteins is an important property. The proteolytic systems of S. thermophilus strains CS5, CS9, CS18 and CS20 have been investigated according to their genomes. The growth and proteolytic abilities of these strains have been analysed in combination with gene expressions of both the proteolytic system and the two-component systems (TCSs) of the specified strains. When the strains are grown in milk, prtS is a key determinant in the fermentation rate of PrtS+ strains (CS5, CS18 and CS20), but other genes are activated in the PrtS− strain CS9. The proteolytic system is regulated by the global transcriptional regulatory factor CodY, especially in the strain CS9. Furthermore, the expression of most genes involved in the proteolytic system and the TCSs were positively correlated with proteolytic activity of strains. The relationship between TCSs and proteolytic gene expression should be investigated in the future.

Reduced fatty acid β-oxidation improves glucose catabolism and liver health in Nile tilapia (Oreochromis niloticus) juveniles fed a high-starch diet

Fish are poor users of dietary carbohydrates and often display prolonged hyperglycemia and fat deposition after feeding high digestible carbohydrate diets. Recently, fatty acid β-oxidation (FAO) inhibition has been reported to increase glucose oxidation in fish. Therefore, this study tested the assumption that the inhibition of FAO with mildronate (MD, a carnitine synthesis inhibitor) might also increase glucose utilization and alleviate adverse effects induced by high starch diet (HSD) in Nile tilapia, Oreochromis niloticus. Nile tilapia juveniles (6.13 ± 0.11 g) were cultured in nine 200-L tanks (30 fish per tank) and divided into three groups (three tanks per group). The fish were fed twice a day (9:00 and 18:30) at 4% body weight by using a normal starch diet (NSD, 30% corn starch), a HSD (45% corn starch), or a HSD supplemented with MD (25 g/kg of diet, HSD + MD) for eight weeks. These three feeds contained approximately 35.8% protein and 6.4% lipid. The fish each tank were weighed every two weeks, and the feeding amount was adjusted accordingly. After the feeding trial, the fish fed on HSD showed higher hepatosomatic index (HSI), visceral somatic index (VSI), serum triglyceride concentration and whole-body and tissue (liver and muscle) lipid contents than those fed on NSD. The fish fed on HSD also had higher relative area of vacuolation in the liver, hepatic malondialdehyde (MDA) content, and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in the serum than those fed on NSD. Moreover, the fish fed on HSD increased serum glucose and insulin concentrations, and hepatic lactate, pyruvate and glycogen contents, but reduced whole-body protein content and dietary protein utilization than those fed on NSD, indicating that HSD induced fat deposition, liver damage, glucose intolerance and lowered protein-sparing effect. However, the fish fed on HSD + MD decreased hepatic carnitine content and FAO activity, attenuated the indexes related to fat deposition and liver damage, improved blood glucose clearance and whole-body protein deposition than those fed on HSD, suggesting that the adverse effects caused by HSD were reversed after FAO inhibition. Furthermore, the fish fed on HSD down-regulated the expression of genes associated with glucose uptake, glycolysis, FAO process, and lipolysis compared to those fed on HSD + MD and NSD, yet up-regulated lipogenic and proteolytic genes. These data suggested that inhibition of FAO improved glucose utilization and alleviated the HSD-induced adverse effects in Nile tilapia. This work demonstrates that, modifying mitochondrial FAO activity regulates the ability of fish to adapt to HSD intake through remodeling energy homeostasis. Our study provides new insights into improving carbohydrate utilization in aquatic animals.

Identification and distinct regulation of three di/tripeptide transporters in Aspergillus oryzae.

The uptake of di/tripeptides is mediated by the proton-dependent oligopeptide transporter (POT) family. In this study, 3 POT family transporters, designated PotA, PotB, and PotC were identified in Aspergillus oryzae. Growth comparison of deletion mutants of these transporter genes suggested that PotB and PotC are responsible for di/tripeptide uptake. PotA, which had the highest sequence similarity to yeast POT (Ptr2), contributed little to the uptake. Nitrogen starvation induced potB and potC expression, but not potA expression. When 3 dipeptides were provided as nitrogen sources, the expression profiles of these genes were different. PrtR, a transcription factor that regulates proteolytic genes, was involved in regulation of potA and potB but not in potC expression. Only potC expression levels were dramatically reduced by disruption of ubrA, an orthologue of yeast ubiquitin ligase UBR1 responsible for PTR2 expression. Expression of individual POT genes is apparently controlled by different regulatory mechanisms.

Inherently and Conditionally Essential Protein Catabolism Genes of Porphyromonas gingivalis.

Proteases are critical virulence determinants of Porphyromonas gingivalis, an emerging Alzheimer's disease, cancer, and arthritis pathogen and established agent of periodontitis. Transposon sequencing has been employed to define the core essential genome of this bacterium and genes conditionally essential in multiple environments - abscess formation; epithelial colonization; and cigarette smoke toxin exposure; as well as to elucidate genes required for iron acquisition and a functional type 9 secretion system. Validated and predicted protein catabolism genes identified include a combination of established virulence factors and a larger set of seemingly more mundane proteolytic genes. The functions and relevance of genes that share essentiality in multiple disease-relevant conditions are examined. These common stress-related genes may represent particularly attractive therapeutic targets for the control of P. gingivalis infections.

Comparative Genome Analysis and Phenotypic Characterization of Clostridium gasigenes CGAS001 Isolated From Chilled Vacuum-Packed Lamb Meat.

Genomic data for psychrophilic bacteria causing blown pack spoilage (BPS) are limited. This study characterizes the genome of a novel Clostridium gasigenes strain CGAS001 isolated from meat juice sample (MJS) of vacuum-packed lamb meat by comparing it with the type strain C. gasigenes DSM 12272 and five strains representing four other BPS-causing Clostridium sensu stricto species. Phenotypic characteristics of the strain, which include biochemical characteristics, antimicrobial resistance and production of putative polyketide, have been determined. The size of its draft genome is 4.1 Mb with 3,845 coding sequences, 28.7% GC content and 95 RNA genes that include 75 tRNAs, 17 rRNAs, and 3 ncRNAs. Average Nucleotide Identity (ANI) and digital DNA–DNA Hybridization (dDDH) predict that C. gasigenes CGAS001 and DSM 12272 constitute a single species (ANI and dDDH = 98.3% for speciation) but two distinct subspecies (dDDH = 73.3% for subspeciation). The genome is characterized by saccharolytic, lipolytic and proteolytic genes as well as hemolysins and phospholipases, which are consistent with its phenotype. The genome also reveals the ability of C. gasigenes to synthesize polyketides which is demonstrated by the antimicrobial activity of a crude polyketide extract against Listeria monocytogenes and Enterococcus devriesei. The strain is resistant to polymyxin B and streptomycin. The genetic and phenotypic analyses suggest that CGAS001 constitutes a novel subspecies of C. gasigenes adapted to a saprophytic lifestyle and can synthesize narrow spectrum antimicrobial compounds.

Testosterone supplementation upregulates androgen receptor expression and translational capacity during severe energy deficit

Testosterone supplementation during energy deficit promotes whole body lean mass accretion, but the mechanisms underlying that effect remain unclear. To elucidate those mechanisms, skeletal muscle molecular adaptations were assessed from muscle biopsies collected before, 1 h, and 6 h after exercise and a mixed meal (40 g protein, 1 h postexercise) following 14 days of weight maintenance (WM) and 28 days of an exercise- and diet-induced 55% energy deficit (ED) in 50 physically active nonobese men treated with 200 mg testosterone enanthate/wk (TEST) or placebo (PLA) during the ED. Participants (n = 10/group) exhibiting substantial increases in leg lean mass and total testosterone (TEST) were compared with those exhibiting decreases in both of these measures (PLA). Resting androgen receptor (AR) protein content was higher and fibroblast growth factor-inducible 14 (Fn14), IL-6 receptor (IL-6R), and muscle ring-finger protein-1 gene expression was lower in TEST vs. PLA during ED relative to WM (P < 0.05). Changes in inflammatory, myogenic, and proteolytic gene expression did not differ between groups after exercise and recovery feeding. Mechanistic target of rapamycin signaling (i.e., translational efficiency) was also similar between groups at rest and after exercise and the mixed meal. Muscle total RNA content (i.e., translational capacity) increased more during ED in TEST than PLA (P < 0.05). These findings indicate that attenuated proteolysis at rest, possibly downstream of AR, Fn14, and IL-6R signaling, and increased translational capacity, not efficiency, may drive lean mass accretion with testosterone administration during energy deficit.

Testosterone Supplementation Upregulates Myogenesis And Attenuates Proteolytic Gene Expression During Severe Energy Deficit

Testosterone Supplementation Upregulates Myogenesis And Attenuates Proteolytic Gene Expression During Severe Energy Deficit

An in vitro study of the effect of the optimal irrigation solution conditions during canine articular surgery.

To establish whether chondrocyte viability, matrix degradation and the induction of proteolytic gene expression in canine cartilage is independent of irrigation fluid osmolality and time following exposure to the irrigation fluid. Canine cartilage explants were exposed to one of three different solution types i) Culture medium (270-280 mOsmol/kg) ii) NaCl 0.9% (302 mOsmol/kg) iii) NaCl 0.9% with sucrose (600 mOsmol/kg). Chondrocyte viability and selected proteolytic gene expression were measured at two time points; immediately following exposure and 24h following exposure. The media samples at 24h following exposure were assessed for sulphated glycosaminoglycan (sGAG) release. In all samples, no cell death was observed across the superficial or deeper layers of the cartilage. When adjusting for time, gene expression was not shown to be dependent on solution type. However for all solution types, Matrix Metalloproteinase 13 (MMP13) and A Disintegrin and Metalloproteinase with Thrombospondin Motifs 5 (ADAMTS5) expression was significantly decreased in cartilage samples at 24h post exposure comparatively to samples tested immediately post exposure. No significant differences were identified in the relative sGAG release between the solution types. Arthroscopic solution irrigation of cartilage explants had no effect on cell viability or proteinase production. At present there is no indication to optimise irrigation fluid osmolarity, as conventional arthroscopic solution was not deleterious to healthy cartilage in this model.