Decreasing the dietary intake of methionine exerts robust anti-adiposity effects in rodents but modest effects in humans. Since cysteine can be synthesized from methionine, animal diets are formulated by decreasing methionine and eliminating cysteine. Such diets exert both methionine restriction (MR) and cysteine restriction (CR), that is, sulfur amino acid restriction (SAAR). Contrarily, SAAR diets formulated for human consumption included cysteine, and thus might have exerted only MR. Epidemiological studies positively correlate body adiposity with plasma cysteine but not methionine, suggesting that CR, but not MR, is responsible for the anti-adiposity effects of SAAR. Whether this is true, and, if so, the underlying mechanisms are unknown. Using methionine- and cysteine-titrated diets, we demonstrate that the anti-adiposity effects of SAAR are due to CR. Data indicate that CR increases serinogenesis (serine biosynthesis from non-glucose substrates) by diverting substrates from glyceroneogenesis, which is essential for fatty acid reesterification and triglyceride synthesis. Molecular data suggest that CR depletes hepatic glutathione and induces Nrf2 and its downstream targets Phgdh (the serine biosynthetic enzyme) and Pepck-M. In mice, the magnitude of SAAR-induced changes in molecular markers depended on dietary fat concentration (60% fat >10% fat), sex (males > females), and age-at-onset (young > adult). Our findings are translationally relevant as we found negative and positive correlations of plasma serine and cysteine, respectively, with triglycerides and metabolic syndrome criteria in a cross-sectional epidemiological study. Controlled feeding of low-SAA, high-polyunsaturated fatty acid diets increased plasma serine in humans. Serinogenesis might be a target for treating hypertriglyceridemia.

• Klíčová slova
• aging, caloric restriction, cysteine, metabolic syndrome, methionine, nutrition, sulfur amino acids, triglycerides,
• MeSH
• aminokyseliny sírové * metabolismus   MeSH
• cystein * metabolismus   MeSH
• lidé MeSH
• metabolismus lipidů MeSH
• methionin metabolismus   MeSH
• myši MeSH
• obezita metabolismus   MeSH
• průřezové studie MeSH
• serin metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• aminokyseliny sírové * MeSH
• cystein * MeSH
• methionin MeSH
• serin MeSH

Cysteine proteases have been discovered in various bloodfeeding ectoparasites. Here, we assemble the available information about the function of these peptidases and reveal their role in hematophagy and parasite development. While most of the data shed light on key proteolytic events that play a role in arthropod physiology, we also report on the association of cysteine proteases with arthropod vectorial capacity. With emphasis on ticks, specifically Ixodes ricinus, we finally propose a model about the contribution of cysteine peptidases to blood digestion and how their concerted action with other tick midgut proteases leads to the absorbance of nutrients by the midgut epithelial cells.

• MeSH
• členovci enzymologie   MeSH
• Culicidae enzymologie   MeSH
• cysteinové proteasy metabolismus   MeSH
• klíšťata enzymologie   MeSH
• paraziti enzymologie   MeSH
• stravovací zvyklosti fyziologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• cysteinové proteasy MeSH

BACKGROUND: Dietary sulfur amino acid restriction (SAAR) improves metabolic health in animals. In this study, we investigated the effect of dietary SAAR on body weight, body composition, resting metabolic rate, gene expression profiles in white adipose tissue (WAT), and an extensive blood biomarker profile in humans with overweight or obesity. METHODS: N = 59 participants with overweight or obesity (73% women) were randomized stratified by sex to an 8-week plant-based dietary intervention low (~ 2 g/day, SAAR) or high (~ 5.6 g/day, control group) in sulfur amino acids. The diets were provided in full to the participants, and both investigators and participants were blinded to the intervention. Outcome analyses were performed using linear mixed model regression adjusted for baseline values of the outcome and sex. RESULTS: SAAR led to a ~ 20% greater weight loss compared to controls (β 95% CI - 1.14 (- 2.04, - 0.25) kg, p = 0.013). Despite greater weight loss, resting metabolic rate remained similar between groups. Furthermore, SAAR decreased serum leptin, and increased ketone bodies compared to controls. In WAT, 20 genes were upregulated whereas 24 genes were downregulated (FDR < 5%) in the SAAR group compared to controls. Generally applicable gene set enrichment analyses revealed that processes associated with ribosomes were upregulated, whereas processes related to structural components were downregulated. CONCLUSION: Our study shows that SAAR leads to greater weight loss, decreased leptin and increased ketone bodies compared to controls. Further research on SAAR is needed to investigate the therapeutic potential for metabolic conditions in humans. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04701346, registered Jan 8th 2021, https://www. CLINICALTRIALS: gov/study/NCT04701346.

• Klíčová slova
• Cysteine, Dietary intervention, Leptin, Methionine restriction, Obesity, Overweight, Randomized controlled trial, Sulfur amino acid restriction, Weight loss,
• MeSH
• aminokyseliny sírové * MeSH
• hmotnostní úbytek MeSH
• ketolátky MeSH
• leptin MeSH
• lidé MeSH
• nadváha * MeSH
• obezita MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• aminokyseliny sírové * MeSH
• ketolátky MeSH
• leptin MeSH

Five 2-substituted 2'-deoxyinosine triphosphates (dRITP) were synthesized and tested as substrates in enzymatic synthesis of minor-groove base-modified DNA. Only 2-methyl and 2-vinyl derivatives proved to be good substrates for Therminator DNA polymerase, whilst all other dRITPs and other tested DNA polymerases did not give full length products in primer extension. The DNA containing 2-vinylhypoxanthine was then further modified through thiol-ene reactions with thiols. Cross-linking reaction between cysteine-containing minor-groove binding dodecapeptide and DNA proceeded thanks to the proximity effect between thiol and vinyl groups inside the minor groove. 2-Substituted dIRTPs and also previously prepared 2-substituted 2'-deoxyadenosine triphosphates (dRATP) were then used for enzymatic synthesis of minor-groove modified DNA to study the effect of minor-groove modifications on cleavage of DNA by type II restriction endonucleases (REs). Although the REs should recognize the sequence through H-bonds in the major groove, some minor-groove modifications also had an inhibiting effect on the cleavage.

• MeSH
• DNA-dependentní DNA-polymerasy metabolismus   MeSH
• DNA biosyntéza   chemie   MeSH
• inosintrifosfát analogy a deriváty   chemická syntéza   metabolismus   MeSH
• konformace nukleové kyseliny MeSH
• restrikční endonukleasy typu II metabolismus   MeSH
• restrikční enzymy metabolismus   MeSH
• substrátová specifita * MeSH
• vinylové sloučeniny chemie   MeSH
• vodíková vazba MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 2'-deoxyinosine triphosphate MeSH Prohlížeč
• DNA-dependentní DNA-polymerasy MeSH
• DNA MeSH
• inosintrifosfát MeSH
• restrikční endonukleasy typu II MeSH
• restrikční enzymy MeSH
• vinylové sloučeniny MeSH

BACKGROUND: Dietary sulfur amino acid (SAA) restriction is an established animal model for increasing lifespan and improving metabolic health. Data from human studies are limited. In the study outlined in this protocol, we will evaluate if dietary SAA restriction can reduce body weight and improve resting energy expenditure (REE) and parameters related to metabolic health. METHOD/DESIGN: Men and women (calculated sample size = 60), aged 18-45 years, with body mass index of 27-35 kg/m2 will be included in a double-blind 8-week dietary intervention study. The participants will be randomized in a 1:1 manner to a diet with either low or high SAA. Both groups will receive an equal base diet consisting of low-SAA plant-based whole foods and an amino acid supplement free of SAA. Contrasting SAA contents will be achieved using capsules with or without methionine and cysteine (SAAhigh, total diet SAA ~ 50-60 mg/kg body weight/day; SAAlow, total diet SAA ~ 15-25 mg/kg body weight/day). The primary outcome is body weight change. Data and material collection will also include body composition (dual X-ray absorptiometry), resting energy expenditure (whole-room indirect calorimetry) and samples of blood, urine, feces and adipose tissue at baseline, at 4 weeks and at study completion. Measures will be taken to promote and monitor diet adherence. Data will be analyzed using linear mixed model regression to account for the repeated measures design and within-subject correlation. DISCUSSION: The strength of this study is the randomized double-blind design. A limitation is the restrictive nature of the diet which may lead to poor compliance. If this study reveals a beneficial effect of the SAAlow diet on body composition and metabolic health, it opens up for new strategies for prevention and treatment of overweight, obesity and its associated disorders. Trial registration ClinicalTrials.gov: NCT04701346, Registration date: January 8th, 2021.

• Klíčová slova
• Adipose tissue, Cysteine restriction, Dietary intervention, Gene expression, Metabolic health, Methionine restriction, Obesity, Plasma biomarkers, Sulfur amino acids, Translational research,
• MeSH
• aminokyseliny sírové * MeSH
• aminokyseliny MeSH
• dospělí MeSH
• energetický metabolismus MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• obezita * MeSH
• randomizované kontrolované studie jako téma MeSH
• složení těla MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• protokol klinické studie MeSH
• Názvy látek
• aminokyseliny sírové * MeSH
• aminokyseliny MeSH

BACKGROUND: In animals, dietary sulfur amino acid restriction (SAAR) improves metabolic health, possibly mediated by altering sulfur amino acid metabolism and enhanced anti-obesogenic processes in adipose tissue. AIM: To assess the effects of SAAR over time on the plasma and urine SAA-related metabolites (sulfurome) in humans with overweight and obesity, and explore whether such changes were associated with body weight, body fat and adipose tissue gene expression. METHODS: Fifty-nine subjects were randomly allocated to SAAR (∼2 g SAA, n = 31) or a control diet (∼5.6 g SAA, n = 28) consisting of plant-based whole-foods and supplemented with capsules to titrate contents of SAA. Sulfurome metabolites in plasma and urine at baseline, 4 and 8 weeks were measured using HPLC and LC-MS/MS. mRNA-sequencing of subcutaneous white adipose tissue (scWAT) was performed to assess changes in gene expression. Data were analyzed with mixed model regression. Principal component analyses (PCA) were performed on the sulfurome data to identify potential signatures characterizing the response to SAAR. RESULTS: SAAR led to marked decrease of the main urinary excretion product sulfate (p < 0.001) and plasma and/or 24-h urine concentrations of cystathionine, sulfite, thiosulfate, H2S, hypotaurine and taurine. PCA revealed a distinct metabolic signature related to decreased transsulfuration and H2S catabolism that predicted greater weight loss and android fat mass loss in SAAR vs. controls (all pinteraction < 0.05). This signature correlated positively with scWAT expression of genes in the tricarboxylic acid cycle, electron transport and β-oxidation (FDR = 0.02). CONCLUSION: SAAR leads to distinct alterations of the plasma and urine sulfurome in humans, and predicted increased loss of weight and android fat mass, and adipose tissue lipolytic gene expression in scWAT. Our data suggest that SAA are linked to obesogenic processes and that SAAR may be useful for obesity and related disorders. TRIAL IDENTIFIER: https://clinicaltrials.gov/study/NCT04701346.

• Klíčová slova
• Adipose tissue, Cysteine, Gene expression, Hydrogen sulfide, Methionine, Randomized controlled trial, Sulfur amino acid restriction, Transsulfuration,
• MeSH
• aminokyseliny sírové * metabolismus   krev   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• metabolom MeSH
• nadváha * metabolismus   genetika   MeSH
• obezita * metabolismus   genetika   MeSH
• regulace genové exprese MeSH
• tuková tkáň * metabolismus   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• aminokyseliny sírové * MeSH

BACKGROUND: Ticks are vectors for a variety of viral, bacterial and parasitic diseases in human and domestic animals. To survive and reproduce ticks feed on host blood, yet our understanding of the intestinal proteolytic machinery used to derive absorbable nutrients from the blood meal is poor. Intestinal digestive processes are limiting factors for pathogen transmission since the tick gut presents the primary site of infection. Moreover, digestive enzymes may find practical application as anti-tick vaccine targets. RESULTS: Using the hard tick, Ixodes ricinus, we performed a functional activity scan of the peptidase complement in gut tissue extracts that demonstrated the presence of five types of peptidases of the cysteine and aspartic classes. We followed up with genetic screens of gut-derived cDNA to identify and clone genes encoding the cysteine peptidases cathepsins B, L and C, an asparaginyl endopeptidase (legumain), and the aspartic peptidase, cathepsin D. By RT-PCR, expression of asparaginyl endopeptidase and cathepsins B and D was restricted to gut tissue and to those developmental stages feeding on blood. CONCLUSION: Overall, our results demonstrate the presence of a network of cysteine and aspartic peptidases that conceivably operates to digest host blood proteins in a concerted manner. Significantly, the peptidase components of this digestive network are orthologous to those described in other parasites, including nematodes and flatworms. Accordingly, the present data and those available for other tick species support the notion of an evolutionary conservation of a cysteine/aspartic peptidase system for digestion that includes ticks, but differs from that of insects relying on serine peptidases.

• Publikační typ
• časopisecké články MeSH

Ticks, as obligate hematophagous ectoparasites, impact greatly on animal and human health because they transmit various pathogens worldwide. Over the last decade, several cystatins from different hard and soft ticks were identified and biochemically analyzed for their role in the physiology and blood feeding lifestyle of ticks. All these cystatins are potent inhibitors of papain-like cysteine proteases, but not of legumain. Tick cystatins were either detected in the salivary glands and/or the midgut, key tick organs responsible for blood digestion and the expression of pharmacologically potent salivary proteins for blood feeding. For example, the transcription of two cystatins named HlSC-1 and Sialostatin L2 was highly upregulated in these tick tissues during feeding. Vaccinating hosts against Sialostatin L2 and Om-cystatin 2 as well as silencing of a cystatin gene from Amblyomma americanum significantly inhibited the feeding ability of ticks. Additionally, Om-cystatin 2 and Sialostatin L possessed strong host immunosuppressive properties by inhibiting dendritic cell maturation due to their interaction with cathepsin S. These two cystatins, together with Sialostatin L2 are the first tick cystatins with resolved three-dimensional structure. Sialostatin L, furthermore, showed preventive properties against autoimmune diseases. In the case of the cystatin Hlcyst-2, experimental evidence showed its role in tick innate immunity, since increased Hlcyst-2 transcript levels were detected in Babesia gibsoni-infected larval ticks and the protein inhibited Babesia growth. Other cystatins, such as Hlcyst-1 or Om-cystatin 2 are assumed to be involved in regulating blood digestion. Only for Bmcystatin was a role in tick embryogenesis suggested. Finally, all the biochemically analyzed tick cystatins are powerful protease inhibitors, and some may be novel antigens for developing anti-tick vaccines and drugs of medical importance due to their stringent target specificity.

• MeSH
• cystatiny farmakologie   MeSH
• inhibitory cysteinových proteinas farmakologie   MeSH
• klíšťata účinky léků   fyziologie   MeSH
• lidé MeSH
• molekulární modely MeSH
• molekulární sekvence - údaje MeSH
• sekvence aminokyselin MeSH
• sekvenční seřazení MeSH
• stravovací zvyklosti účinky léků   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• cystatiny MeSH
• inhibitory cysteinových proteinas MeSH

Tick saliva injected into the vertebrate host contains bioactive anti-proteolytic proteins from the cystatin family; however, the molecular basis of their unusual biochemical and physiological properties, distinct from those of host homologs, is unknown. Here, we present Ricistatin, a novel secreted cystatin identified in the salivary gland transcriptome of Ixodes ricinus ticks. Recombinant Ricistatin inhibited host-derived cysteine cathepsins and preferentially targeted endopeptidases, while having only limited impact on proteolysis driven by exopeptidases. Determination of the crystal structure of Ricistatin in complex with a cysteine cathepsin together with characterization of structural determinants in the Ricistatin binding site explained its restricted specificity. Furthermore, Ricistatin was potently immunosuppressive and anti-inflammatory, reducing levels of pro-inflammatory cytokines IL-6, IL-1β, and TNF-α and nitric oxide in macrophages; IL-2 and IL-9 levels in Th9 cells; and OVA antigen-induced CD4+ T cell proliferation and neutrophil migration. This work highlights the immunotherapeutic potential of Ricistatin and, for the first time, provides structural insights into the unique narrow selectivity of tick salivary cystatins determining their bioactivity.

• Klíčová slova
• Cystatins, Host–parasite interactions, Ixodes ricinus, Protease inhibition, Protein structure, Tick saliva,
• MeSH
• cystatiny * farmakologie   MeSH
• cystein metabolismus   MeSH
• endopeptidasy metabolismus   MeSH
• kathepsiny metabolismus   MeSH
• klíště * chemie   MeSH
• obratlovci MeSH
• proteasy metabolismus   MeSH
• slinné cystatiny chemie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cystatiny * MeSH
• cystein MeSH
• endopeptidasy MeSH
• kathepsiny MeSH
• proteasy MeSH
• slinné cystatiny MeSH

Cysteine-cysteine chemokine ligand 5 (CCL5) with immunoregulatory and inflammatory activities has an important role in granuloma formations that activates and stimulates T-cells and macrophages. Cysteine-cysteine chemokine receptor 5 (CCR5) is a chemokine receptor, which is important for migration of immune cells to site of infection. In the present study we investigated the possible association between CCL5 -403G/A (rs2107538), CCL5 -28C/G (rs2280788) and CCR5 Δ32 polymorphisms and pulmonary tuberculosis (PTB) in an Iranian population. This case-control study was performed on 160 patients with pulmonary tuberculosis and 160 unrelated healthy subjects. The CCL5 -403G/A, CCL5 -28C/G and CCR5 Δ32 polymorphisms were genotyped by allele-specific polymerase chain reaction (AS-PCR), tetra amplification refractory mutation system polymerase chain reaction (T-ARMS PCR) and PCR, respectively. Our results showed that GA as well as GA+AA genotypes of CCL5 -403G/A (rs2107538) increased the risk of PTB in comparison with GG genotype (OR=1.70, 95% CI=1.03-2.81, P=0.038 and OR=1.64, 95% CI=1.00-2.68, P=0.049, respectively). No significant association was found between CCL5 -28C/G as well as CCR5 Δ32 polymorphism and PTB risk. In conclusion, our findings proposed that CCL5 -403G>A polymorphism may be a risk factor for susceptibility to PTB in our population. Larger sample sizes with different ethnicities are required to validate our findings.

• Klíčová slova
• CCL5, CCR5, Polymorphism, Tuberculosis,
• MeSH
• chemokin CCL5 genetika   MeSH
• dospělí MeSH
• genetická predispozice k nemoci genetika   MeSH
• genotyp MeSH
• lidé středního věku MeSH
• lidé MeSH
• plicní tuberkulóza genetika   MeSH
• polymerázová řetězová reakce MeSH
• polymorfismus délky restrikčních fragmentů * MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Geografické názvy
• Írán MeSH
• Názvy látek
• CCL5 protein, human MeSH Prohlížeč
• chemokin CCL5 MeSH