Sulfate is present in foods, beverages, and drinking water. Its reduction and concentration in the gut depend on the intestinal microbiome activity, especially sulfate-reducing bacteria (SRB), which can be involved in inflammatory bowel disease (IBD). Assimilatory sulfate reduction (ASR) is present in all living organisms. In this process, sulfate is reduced to hydrogen sulfide and then included in cysteine and methionine biosynthesis. In contrast to assimilatory sulfate reduction, the dissimilatory process is typical for SRB. A terminal product of this metabolism pathway is hydrogen sulfide, which can be involved in gut inflammation and also causes problems in industries (due to corrosion effects). The aim of the review was to compare assimilatory and dissimilatory sulfate reduction (DSR). These processes occur in some species of intestinal bacteria (e.g., Escherichia and Desulfovibrio genera). The main attention was focused on the description of genes and their location in selected strains. Their coding expression of the enzymes is associated with anabolic processes in various intestinal bacteria. These analyzed recent advances can be important factors for proposing possibilities of metabolic pathway extension from hydrogen sulfide to cysteine in intestinal SRB. The switch from the DSR metabolic pathway to the ASR metabolic pathway is important since toxic sulfide is not produced as a final product.

• MeSH
• Bacteria patogenita   MeSH
• lidé MeSH
• metabolické sítě a dráhy MeSH
• sírany metabolismus   MeSH
• střevní mikroflóra imunologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Indoxyl sulfate (IS), a uremic toxin, is considered as a risk factor for accelerated atherosclerosis in patients with chronic kidney disease. As uptake of oxidized low-density lipoprotein (Ox-LDL) in macrophages is a key event in the progression of atherosclerosis, the aim of this study was to determine direct effects of IS on uptake of Ox-LDL in macrophages. Flow cytometric analysis revealed that IS significantly stimulated Ox-LDL uptake by THP-1 macrophages in both dose- and time-dependent manners. A CD36 inhibitor, sulfosuccinimidyl oleate (SSO), and ERK1/2 inhibitors, PD98059 and U0126, could suppress the IS-stimulated Ox-LDL uptake. IS also stimulated CD36 expression, which was inhibited by PD98059 and U0126. Western blotting analysis showed that IS significantly activated ERK1/2 mitogen-activated protein kinase (MAPK) pathway by increasing its phosphorylation level. Further, CCK-8 assay showed that IS exerted its effects without affecting cell viability. In conclusion, IS stimulated Ox-LDL uptake through up-regulation of CD36 expression in THP-1 macrophages, partly via ERK1/2 MAPK pathway. This might be one of the mechanisms underlying the progression of atherosclerosis in patients with chronic kidney disease.

• MeSH
• antigeny CD36 fyziologie   MeSH
• ateroskleróza * patofyziologie   MeSH
• chronická renální insuficience * komplikace   MeSH
• extracelulárním signálem regulované MAP kinasy fyziologie   MeSH
• indican * fyziologie   škodlivé účinky   MeSH
• lipoproteiny LDL fyziologie   MeSH
• makrofágy fyziologie   MeSH
• MAP kinasový signální systém fyziologie   účinky léků   MeSH
• nádorové buněčné linie fyziologie   MeSH
• průtoková cytometrie MeSH
• techniky in vitro MeSH
• viabilita buněk účinky léků   MeSH
• Publikační typ
• práce podpořená grantem MeSH

INTRODUCTION: High indoxyl sulfate (IS) concentration is a serious problem for patients with CKD increasing the risk of cardiovascular diseases and CKD progression. Thus, the methods of decreasing the toxin concentrations are highly desired. The study aimed to discover the role of selected intestine-related factors on IS concentration. METHODS: We evaluated the impact of ABCG2 and ABCC2 polymorphisms influencing activity and protein intake by normalized protein catabolic rate. Additionally, we examined the relation of IS and uric acid (UA) that can share common elimination transporters. A monocentric, prospective, open cohort pilot study was performed on 108 patients undergoing dialysis treatment. RESULTS: The positive effect of residual diuresis on the reduction of IS levels was confirmed (p = 0.005). Also, an increase in IS depending on the dietary protein intake was confirmed (p = 0.040). No significant correlation between ABC gene polymorphisms was observed either, suggesting the negligible role of ABCG2 and ABCC2 in the elimination of IS in small bowel. The significant difference was observed for UA where ABCG2 421C>A (rs72552713) gene polymorphism was higher (505.3 μmol/L) in comparison with a wild-type genotype (360.5 μmol/L). CONCLUSION: No evidence of bowel elimination pathway via ABCC2 and ABCG2 transporters was found in renal replacement therapy patients.

• MeSH
• chronická renální insuficience * terapie   etiologie   MeSH
• dialýza ledvin metody   MeSH
• dietní proteiny MeSH
• indican * MeSH
• intestinální eliminace MeSH
• lidé MeSH
• pilotní projekty MeSH
• prospektivní studie MeSH
• uremické toxiny MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Signal transducer and activator of transcription 3 (STAT3) is phosphorylated by various kinases, several of which have been implicated in aberrant fibroblast activation in fibrotic diseases including systemic sclerosis (SSc). Here we show that profibrotic signals converge on STAT3 and that STAT3 may be an important molecular checkpoint for tissue fibrosis. STAT3 signaling is hyperactivated in SSc in a TGFβ-dependent manner. Expression profiling and functional studies in vitro and in vivo demonstrate that STAT3 activation is mediated by the combined action of JAK, SRC, c-ABL, and JNK kinases. STAT3-deficient fibroblasts are less sensitive to the pro-fibrotic effects of TGFβ. Fibroblast-specific knockout of STAT3, or its pharmacological inhibition, ameliorate skin fibrosis in experimental mouse models. STAT3 thus integrates several profibrotic signals and might be a core mediator of fibrosis. Considering that several STAT3 inhibitors are currently tested in clinical trials, STAT3 might be a candidate for molecular targeted therapies of SSc.

• MeSH
• aktivace enzymů MeSH
• benzensulfonáty chemie   MeSH
• biopsie MeSH
• bleomycin chemie   MeSH
• dospělí MeSH
• fibroblasty metabolismus   MeSH
• fibróza metabolismus   MeSH
• fosforylace MeSH
• kolagen chemie   MeSH
• konfokální mikroskopie MeSH
• kůže metabolismus   MeSH
• kyseliny aminosalicylové chemie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• myši MeSH
• receptory transformujícího růstového faktoru beta metabolismus   MeSH
• senioři MeSH
• signální transdukce fyziologie   MeSH
• systémová sklerodermie metabolismus   MeSH
• transformující růstový faktor beta metabolismus   MeSH
• transkripční faktor STAT3 metabolismus   MeSH
• zánět MeSH
• zvířata MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• myši MeSH
• senioři MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Pregnenolone sulfate (PS), an endogenously occurring neurosteroid, has been shown to modulate the activity of several neurotransmitter-gated channels, including the N-methyl-D-aspartate receptor (NMDAR). NMDARs are glutamate-gated ion channels involved in excitatory synaptic transmission, synaptic plasticity, and excitotoxicity. To determine the mechanism that controls PS sensitivity of NMDARs, we measured NMDAR responses induced by exogenous agonist application in voltage-clamped HEK293 cells expressing NR1/NR2B NMDARs and cultured rat hippocampal neurons. We report that PS potentiates the amplitude of whole-cell recorded NMDAR responses in cultured hippocampal neurons and HEK293 cells; however, the potentiating effect of PS on NMDAR in outside-out patches isolated from cultured hippocampal neurons and HEK293 cells was lost within 2 min after patch isolation in a neurosteroid-specific manner. The rate of diminution of the PS potentiating effect was slowed by protein phosphatase inhibitors. Treatment of cultured hippocampal neurons with a nonspecific protein kinase inhibitor and a specific protein kinase A (PKA) inhibitor diminished PS-induced potentiation, which was recovered by adding a PKA, but not a protein kinase C (PKC), activator. These results suggest that the effect of PS on NMDARs is controlled by cellular mechanisms that are mediated by dephosphorylation/phosphorylation pathways.

• MeSH
• buněčné linie MeSH
• fosforylace MeSH
• hipokampus fyziologie   MeSH
• krysa rodu rattus MeSH
• kultivované buňky MeSH
• lidé MeSH
• membránové potenciály MeSH
• metoda terčíkového zámku MeSH
• neurony fyziologie   MeSH
• pregnenolon metabolismus   MeSH
• proteinfosfatasy antagonisté a inhibitory   MeSH
• proteinkinasa C metabolismus   MeSH
• proteinkinasy závislé na cyklickém AMP metabolismus   MeSH
• receptory N-methyl-D-aspartátu agonisté   metabolismus   MeSH
• vápník metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• práce podpořená grantem MeSH

The diagnostic prevalence of autism spectrum disorders (ASD) shows boys to be more affected than girls. Due to this reason, there is a lack of research including and observing ASD girls. Present study was aimed to detect hormones of steroidogenesis pathway in prepubertal girls (n = 16) diagnosed with ASD and sex and age matched neurotypical controls (CTRL, n = 16). Collected plasma served for detection of conjugated and unconjugated steroids using gas chromatography tandem-mass spectrometry. We observed higher levels of steroids modulating ionotropic receptors, especially, GABAergic steroids and pregnenolone sulfate in ASD group. Concentration of many steroids throughout the pathway tend to be higher in ASD girls compared to CTRL. Pregnenolone and its isomers together with polar progestins and androstanes, i.e. sulfated steroids, were found to be higher in ASD group in comparison with CTRL group. Based on steroid product to precursor ratios, ASD group showed higher levels of sulfated/conjugated steroids suggesting higher sulfotransferase or lower steroid sulfatase activity and we also obtained data indicating lower activity of steroid 11β-hydroxylase compared to CTRL group despite higher corticosterone level observed in ASD. These findings need to be generalized in future studies to examine both genders and other age groups.

• MeSH
• dítě MeSH
• lidé MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
• poruchy autistického spektra * metabolismus   MeSH
• předškolní dítě MeSH
• pregnenolon * metabolismus   krev   MeSH
• steroidy metabolismus   krev   MeSH
• studie případů a kontrol MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Searching for new strategies for effective elimination of human prostate cancer cells, we investigated the cooperative cytotoxic action of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and two platinum-based complexes, cisplatin or LA-12, and related molecular mechanisms. We demonstrated a notable ability of cisplatin or LA-12 to enhance the sensitivity of several human prostate cancer cell lines to TRAIL-induced cell death via an engagement of mitochondrial apoptotic pathway. This was accompanied by augmented Bid cleavage, Bak activation, loss of mitochondrial membrane potential, activation of caspase-8, -10, -9, and -3, and XIAP cleavage. RNAi-mediated silencing of Bid or Bak in Bax-deficient DU 145 cells suppressed the drug combination-induced cytotoxicity, further underscoring the involvement of mitochondrial signaling. The caspase-10 was dispensable for enhancement of cisplatin/LA-12 and TRAIL combination-induced cell death and stimulation of Bid cleavage. Importantly, we newly demonstrated LA-12-mediated enhancement of TRAIL-induced cell death in cancer cells derived from human patient prostate tumor specimens. Our results provide convincing evidence that employing TRAIL combined with cisplatin/LA-12 could contribute to more effective killing of prostate cancer cells compared to the individual action of the drugs, and offer new mechanistic insights into their cooperative anticancer action.

• MeSH
• amantadin analogy a deriváty   farmakologie   MeSH
• apoptóza účinky léků   MeSH
• cisplatina farmakologie   MeSH
• kaspasa 10 metabolismus   MeSH
• lidé MeSH
• mitochondrie účinky léků   metabolismus   MeSH
• nádory prostaty metabolismus   patologie   MeSH
• organoplatinové sloučeniny farmakologie   MeSH
• protein Bid metabolismus   MeSH
• protein TRAIL metabolismus   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

In our study, we tested the hypothesis whether valproic acid (VPA) in therapeutic concentrations has potential to affect expression of CYP3A4 and MDR1 via constitutive androstane receptor (CAR) and pregnane X receptor (PXR) pathways. Interaction of VPA with CAR and PXR nuclear receptors was studied using luciferase reporter assays, real-time reverse transcriptase polymerase chain reaction (RT-PCR), electrophoretic mobility shift assay (EMSA), and analysis of CYP3A4 catalytic activity. Using transient transfection reporter assays in HepG2 cells, VPA was recognized to activate CYP3A4 promoter via CAR and PXR pathways. By contrast, a significant effect of VPA on MDR1 promoter activation was observed only in CAR-cotransfected HepG2 cells. These data well correlated with up-regulation of CYP3A4 and MDR1 mRNAs analyzed by real-time RT-PCR in cells transfected with expression vectors encoding CAR or PXR and treated with VPA. In addition, VPA significantly up-regulated CYP3A4 mRNA in primary hepatocytes and augmented the effect of rifampicin. EMSA experiments showed VPA-mediated augmentation of CAR/retinoid X receptor alpha heterodimer binding to direct repeat 3 (DR3) and DR4 responsive elements of CYP3A4 and MDR1 genes, respectively. Finally, analysis of specific CYP3A4 catalytic activity revealed its significant increase in VPA-treated LS174T cells transfected with PXR. In conclusion, we provide novel insight into the mechanism by which VPA affects gene expression of CYP3A4 and MDR1 genes. Our results demonstrate that VPA has potential to up-regulate CYP3A4 and MDR1 through direct activation of CAR and/or PXR pathways. Furthermore, we suggest that VPA synergistically augments the effect of rifampicin in transactivation of CYP3A4 in primary human hepatocytes.

• MeSH
• aktivace transkripce účinky léků   MeSH
• antikonvulziva farmakologie   MeSH
• aromatické hydroxylasy genetika   MeSH
• cytochrom P-450 CYP3A MeSH
• enzymová indukce MeSH
• financování organizované MeSH
• genetická transkripce účinky léků   MeSH
• hepatocyty enzymologie   metabolismus   účinky léků   MeSH
• hydroxylace MeSH
• kyselina valproová farmakologie   MeSH
• lidé MeSH
• luciferasy MeSH
• messenger RNA metabolismus   MeSH
• N-demethylasy genetika   MeSH
• nádorové buněčné linie MeSH
• oximy farmakologie   MeSH
• P-glykoprotein biosyntéza   genetika   MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• promotorové oblasti (genetika) účinky léků   MeSH
• receptory cytoplazmatické a nukleární metabolismus   účinky léků   MeSH
• reportérové geny MeSH
• retardační test MeSH
• retinoidní X receptor alfa metabolismus   účinky léků   MeSH
• rifampin farmakologie   MeSH
• steroidní receptory metabolismus   účinky léků   MeSH
• synergismus léků MeSH
• systém (enzymů) cytochromů P-450 biosyntéza   genetika   MeSH
• testosteron metabolismus   MeSH
• thiazoly farmakologie   MeSH
• transfekce MeSH
• transkripční faktory metabolismus   účinky léků   MeSH
• upregulace MeSH
• Check Tag
• lidé MeSH

Silymarin, an extract from milk thistle (Silybum marianum) fruits, is consumed in various food supplements. The metabolism of silymarin flavonolignans in mammals is complex, the exact structure of their metabolites still remains partly unclear and standards are not commercially available. This work is focused on the preparation of sulfated metabolites of silymarin flavonolignans. Sulfated flavonolignans were prepared using aryl sulfotransferase from Desulfitobacterium hafniense and p-nitrophenyl sulfate as a sulfate donor and characterized by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR). Their 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and N,N-dimethyl-p-phenylenediamine (DMPD) radical scavenging; ferric (FRAP) and Folin⁻Ciocalteu reagent (FCR) reducing activity; anti-lipoperoxidant potential; and effect on the nuclear erythroid 2-related factor 2 (Nrf2) signaling pathway were examined. Pure silybin A 20-O-sulfate, silybin B 20-O-sulfate, 2,3-dehydrosilybin-20-O-sulfate, 2,3-dehydrosilybin-7,20-di-O-sulfate, silychristin-19-O-sulfate, 2,3-dehydrosilychristin-19-O-sulfate, and silydianin-19-O-sulfate were prepared and fully characterized. Sulfated 2,3-dehydroderivatives were more active in FCR and FRAP assays than the parent compounds, and remaining sulfates were less active chemoprotectants. The sulfated flavonolignans obtained can be now used as authentic standards for in vivo metabolic experiments and for further research on their biological activity.

• MeSH
• antioxidancia chemie   MeSH
• flavonolignany chemie   MeSH
• hmotnostní spektrometrie MeSH
• magnetická rezonanční spektroskopie MeSH
• molekulární struktura MeSH
• ostropestřec mariánský chemie   MeSH
• ovoce chemie   MeSH
• potravní doplňky MeSH
• rostliny chemie   ultrastruktura   MeSH
• scavengery volných radikálů chemie   MeSH
• sírany chemie   MeSH
• Publikační typ
• časopisecké články MeSH

In search for novel strategies in colon cancer treatment, we investigated the unique ability of platinum(IV) complex LA-12 to efficiently enhance the killing effects of tumor necrosis factor-related apoptosis inducing ligand (TRAIL), and compared it with the sensitizing action of cisplatin. We provide the first evidence that LA-12 primes human colon cancer cells for TRAIL-induced cytotoxicity by p53-independent activation of the mitochondrial apoptotic pathway. The cooperative action of LA-12 and TRAIL was associated with stimulation of Bax/Bak activation, drop of mitochondrial membrane potential, caspase-9 activation, and a shift of the balance among Bcl-2 family proteins in favor of the pro-apoptotic members. In contrast to cisplatin, LA-12 was a potent inducer of ERK-mediated Noxa and BimL protein upregulation, and more effectively enhanced TRAIL-induced apoptosis in the absence of Bax. The cooperative action of LA-12 and TRAIL was augmented following the siRNA-mediated silencing of Mcl-1 in both Bax proficient/deficient cells. We newly demonstrated that LA-12 induced ERK-mediated c-Myc upregulation, and proved that c-Myc silencing inhibited the mitochondrial activation and apoptosis in colon cancer cells treated with LA-12 and TRAIL. The LA-12-mediated sensitization to TRAIL-induced apoptosis was demonstrated in several colon cancer cell lines, further underscoring the general relevance of our findings. The selective action of LA-12 was documented by preferential priming of cancer but not normal colon cancer cells to TRAIL killing effects. Our work highlights the promising potential of LA-12 over cisplatin to enhance the colon cancer cell sensitivity to TRAIL-induced apoptosis, and provides new mechanistic insights into their cooperative action.

• MeSH
• amantadin analogy a deriváty   farmakologie   MeSH
• antitumorózní látky farmakologie   MeSH
• apoptóza účinky léků   genetika   MeSH
• cisplatina farmakologie   MeSH
• geny p53 MeSH
• HCT116 buňky účinky léků   MeSH
• lidé MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• mitochondrie účinky léků   metabolismus   MeSH
• nádorové buňky kultivované MeSH
• nádory tračníku farmakoterapie   metabolismus   patologie   MeSH
• organoplatinové sloučeniny farmakologie   MeSH
• protein Bak metabolismus   MeSH
• protein TRAIL metabolismus   farmakologie   MeSH
• protein X asociovaný s bcl-2 genetika   metabolismus   MeSH
• protoonkogenní proteiny c-bcl-2 metabolismus   MeSH
• protoonkogenní proteiny c-myc genetika   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH