Nanomedicine for treating post-viral infectious disease syndrome is at an emerging stage. Despite promising results from preclinical studies on conventional antioxidants, their clinical translation as a therapy for treating post-COVID conditions remains challenging. The limitations are due to their low bioavailability, instability, limited transport to the target tissues, and short half-life, requiring frequent and high doses. Activating the immune system during coronavirus (SARS-CoV-2) infection can lead to increased production of reactive oxygen species (ROS), depleted antioxidant reserve, and finally, oxidative stress and neuroinflammation. To tackle this problem, we developed an antioxidant nanotherapy based on lipid (vesicular and cubosomal types) nanoparticles (LNPs) co-encapsulating ginkgolide B and quercetin. The antioxidant-loaded nanocarriers were prepared by a self-assembly method via hydration of a lyophilized mixed thin lipid film. We evaluated the LNPs in a new in vitro model for studying neuronal dysfunction caused by oxidative stress in coronavirus infection. We examined the key downstream signaling pathways that are triggered in response to potassium persulfate (KPS) causing oxidative stress-mediated neurotoxicity. Treatment of neuronally-derived cells (SH-SY5Y) with KPS (50 mM) for 30 min markedly increased mitochondrial dysfunction while depleting the levels of both glutathione peroxidase (GSH-Px) and tyrosine hydroxylase (TH). This led to the sequential activation of apoptotic and necrotic cell death processes, which corroborates with the crucial implication of the two proteins (GSH-Px and TH) in the long-COVID syndrome. Nanomedicine-mediated treatment with ginkgolide B-loaded cubosomes and vesicular LNPs showed minimal cytotoxicity and completely attenuated the KPS-induced cell death process, decreasing apoptosis from 32.6% (KPS) to 19.0% (MO-GB), 12.8% (MO-GB-Quer), 14.8% (DMPC-PEG-GB), and 23.6% (DMPC-PEG-GB-Quer) via free radical scavenging and replenished GSH-Px levels. These findings indicated that GB-LNPs-based nanomedicines may protect against KPS-induced apoptosis by regulating intracellular redox homeostasis.

• MeSH
• antioxidancia * farmakologie   MeSH
• COVID-19 metabolismus   MeSH
• farmakoterapie COVID-19 * MeSH
• ginkgolidy * farmakologie   MeSH
• glutathionperoxidasa * metabolismus   MeSH
• laktony farmakologie   MeSH
• lidé MeSH
• nanočástice * MeSH
• nanomedicína * metody   MeSH
• neurony účinky léků   virologie   MeSH
• oxidační stres * účinky léků   MeSH
• quercetin farmakologie   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• SARS-CoV-2 účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Více než 85 % pacientů s karcinomem pankreatu (PC) je spjato s paraneoplastickou hyperglykémií, kterou označujeme jako diabetes asociovaný s karcinomem pankreatu (DMPC). Objevuje se již 2 roky před diagnózou karcinomu pankreatu a lze jej označit za časný symptom PC. Pouze 1 % recentně diagnostikovaných diabetiků (RODM) nad 50 let má PC. Současné diagnostické metody neumožňují odlišit DMPC od DM 2. typu (DM2), tvořící větší část RODM. Ve snaze specifikovat rozdíly mezi DMPC a DM2 lze využít kombinaci metod chiroptické a vibrační spektroskopie - elektronový cirkulární dichroismus (ECD), Ramanovu optickou aktivitu (ROA), infračervenou (IR) a Ramanovu spektroskopii. Primárním cílem je zjistit spolehlivost (senzitivita, specificita) pokročilých spektroskopických metod v detekci PC/DMPC a DM2. V letech 2016–2019 bude do studie zařazeno 90 pacientů s PC/DMPC, 90 pacientů s RODM, 45 pacientů s DM2 a 45 zdravých subjektů. Všem bude odebrána a dle standardů zpracována krev, následně analyzovány biomolekuly krevní plazmy pomocí pokročilých spektroskopických metod.; In more than 85% of cases, pancreatic cancer (PC) is connected with paraneoplastic hyperglycemia - diabetes mellitus associated with PC (DMPC) that appears 2 years before PC diagnosis and is considered to be an early symptom of PC. However, only 1% of recent onset diabetics (RODM) over 50 years have PC. The current diagnostic procedures fall short in distinguishing DMPC from the very frequent type 2 diabetes mellitus (DM2), which represents most of RODM cases. In order to specify the differences between DMPC and DM2, a new approach based on a combination of chiroptical and vibrational spectroscopy (electronic circular dichroism (ECD), Raman optical activity (ROA), infrared (IR) and Raman spectroscopy) will be tested. The main aim is to determine the efficacy (sensitivity and specificity) of spectroscopic methods for PC/DMPC and DM2. Between 2016–2019 a total of 120 PC/DMPCs, 90 RODMs, 45 DM2 patients and 45 healthy controls will be enrolled. Blood will be collected from all individuals, processed; and subsequently, plasmatic biomolecules analyzed by advanced spectroscopic methods.

• MeSH
• časná detekce nádoru MeSH
• hematologické testy MeSH
• komplikace diabetu MeSH
• lidé MeSH
• nádorové biomarkery MeSH
• nádory slinivky břišní diagnostické zobrazování   MeSH
• reprodukovatelnost výsledků MeSH
• spektrální analýza MeSH
• Check Tag
• lidé MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• onkologie
• gastroenterologie
• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

Our study demonstrates that nanoplasmonic sensing (NPS) can be utilized for the determination of the phase transition temperature (Tm) of phospholipids. During the phase transition, the lipid bilayer undergoes a conformational change. Therefore, it is presumed that the Tm of phospholipids can be determined by detecting conformational changes in liposomes. The studied lipids included 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), and 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC). Liposomes in gel phase are immobilized onto silicon dioxide sensors and the sensor cell temperature is increased until passing the Tm of the lipid. The results show that, when the system temperature approaches the Tm, a drop of the NPS signal is observed. The breakpoints in the temperatures are 22.5 °C, 41.0 °C, and 55.5 °C for DMPC, DPPC, and DSPC, respectively. These values are very close to the theoretical Tm values, i.e., 24 °C, 41.4 °C, and 55 °C for DMPC, DPPC, and DSPC, respectively. Our studies prove that the NPS methodology is a simple and valuable tool for the determination of the Tm of phospholipids.

• MeSH
• fosfolipidy chemie   MeSH
• liposomy chemie   MeSH
• povrchová plasmonová rezonance metody   MeSH
• tranzitní teplota * MeSH
• změna skupenství * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Myotonická dystrofie je nejčastější svalová dystrofie dospělého věku. Jde o autozomálně dominantní onemocnění charakterizované klíčovou triádou příznaků: svalová slabost, myotonie a katarakta. Podstatou je expanze trinukleotidových sekvencí CTG v genu DMPK u myotonické dystrofie 1. typu (MD1) a expanze tetranukleotidových sekvencí v genu CNBP/ ZNF9 u myotonické dystrofie 2. typu (MD2). Akumulace RNA potom vede k ovlivnění celé řady dalších genů, což je podkladem rozsáhlého postižení mnoha systémů. MD1 se manifestuje od narození do dospělosti a tíže a začátek koreluje s počtem opakování. MD2 se rozvíjí vždy pouze v dospělosti. Důležitý je také rozdíl v distribuci svalové slabosti. V případě MD1 jde především o mimické svalstvo, šíjové svalstvo a distální svaly horních a dolních končetin. U MD2 se jedná dominantně o kořenové svaly, především DK. Tato lokalizace také dala chorobě dříve používané synonymum: proximální myotonická myopatie. Na rozdíl od MD1, která má celosvětový výskyt, se MD2 dominantně vyskytuje ve střední Evropě a Skandinávii. U obou forem je postižen i převodní systém srdeční, kognitivní a exekutivní funkce, zažívací trakt a řada dalších orgánů. Onemocnění je u MD1 zpravidla závažnější než u MD2. Vzhledem k postižení řady systému, nejen svalů, je v péči o nemocné důležitý multidisciplinární přístup.

Myotonic dystrophy is the most frequent muscular dystrophy of adult age characterised by muscle weakness, myotonia, cataracts, and autosomal dominant inheritance. The disease is caused by trinucleotide expansion in the DMPK gene in case of myotonic dystrophy type 1 (MD1) and tetranucleotide expansion in the CNBP/ZNF9 gene in myotonic dystrophy type 2 (MD2). The accumulation of RNA transcripts and its toxicity leads to dysregulation of many other genes, providing a clue for understanding of the broad clinical spectrum of the disease. MD1 manifests from birth (congenital) to adulthood. Severity and time of onset correlate with the number of repeats. On the contrary, MD2 is a disease with an onset during adult age only. Localisation of muscle weakness is also diff erent; the facial muscles, paraspinal, distal muscles of upper and lower limbs are aff ected in case of MD1 and the proximal muscles, esp. of lower limbs are involved in patients suff ering from MD2 – this localisation determined the former name: proximal myotonic myopathy. In contrast to MD1 that has worldwide prevalence, MD2 is predominantly restricted to middle and northern Europe. The heart conduction system (arrhythmias) is aff ected in patients with either type of the disease. In general, the impact of the disease is more severe in patients with MD1 than in MD2. Due to involvement of many systems, a multidisciplinary approach and team should be involved in the management of these patients.

• Klíčová slova
• proximální myotonická myopatie,
• MeSH
• katarakta MeSH
• lidé MeSH
• mutace MeSH
• myotonická dystrofie * diagnóza   genetika   patofyziologie   terapie   MeSH
• myotonie MeSH
• srdeční arytmie komplikace   MeSH
• Check Tag
• lidé MeSH

Procyanidins, contained in many products abundant in human diet, exhibit high biological activity. However, this activity has not been fully explained at cellular and molecular levels. In this study, we determine the mechanism of interaction of procyanidin B3 with model lipid membrane. This mechanism was established on the basis of changes induced by B3 in the physical properties of lipid bilayer. The changes were investigated using steady state and time-resolved fluorescence, DSC, and FTIR. We show that procyanidin B3 causes changes in the arrangement of the polar heads of lipids, order of their acyl chains and the main lipid phase transition temperature. Furthermore, its presence in the membrane leads to a reduction in membrane dipole potential. Procyanidin B3 is anchored to membrane via hydrogen bonds formed between its OH groups and the PO2- and CO groups of lipids, causing changes in both hydrophilic and hydrophobic regions of the membrane.

• MeSH
• 2-naftylamin analogy a deriváty   chemie   MeSH
• biflavonoidy chemie   MeSH
• diferenciální skenovací kalorimetrie MeSH
• dihydropyridiny chemie   MeSH
• dimyristoylfosfatidylcholin chemie   MeSH
• fluorescenční spektrometrie MeSH
• hydrofobní a hydrofilní interakce MeSH
• katechin chemie   MeSH
• laurany chemie   MeSH
• lipidové dvojvrstvy chemie   MeSH
• proantokyanidiny chemie   MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• teplota MeSH
• termodynamika MeSH
• vodíková vazba MeSH
• změna skupenství MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The transient receptor potential melastatin 4 (TRPM4) is a calcium-activated non-selective ion channel broadly expressed in a variety of tissues. Receptor has been identified as a crucial modulator of numerous calcium dependent mechanisms in the cell such as immune response, cardiac conduction, neurotransmission and insulin secretion. It is known that phosphoinositide lipids (PIPs) play a unique role in the regulation of TRP channel function. However the molecular mechanism of this process is still unknown. We characterized the binding site of PIP2 and its structural analogue PIP3 in the E733-W772 proximal region of the TRPM4 N-terminus via biophysical and molecular modeling methods. The specific positions R755 and R767 in this domain were identified as being important for interactions with PIP2/PIP3 ligands. Their mutations caused a partial loss of PIP2/PIP3 binding specificity. The interaction of PIP3 with TRPM4 channels has never been described before. These findings provide new insight into the ligand binding domains of the TRPM4 channel.

• MeSH
• dimyristoylfosfatidylcholin analogy a deriváty   metabolismus   MeSH
• fosfatidylinositol-4,5-difosfát metabolismus   MeSH
• kationtové kanály TRPM chemie   metabolismus   MeSH
• lidé MeSH
• molekulární sekvence - údaje MeSH
• peptidové fragmenty chemie   metabolismus   MeSH
• sekundární struktura proteinů MeSH
• sekvence aminokyselin MeSH
• simulace molekulového dockingu MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The influence of maltose-modified poly(propylene imine) (PPI) dendrimers on dimyristoylphosphatidylcholine (DMPC) or dimyristoylphosphatidylcholine/dimyristoylphosphatidylglycerol (DMPC/DMPG) (3%) liposomes was studied. Fourth generation (G4) PPI dendrimers with primary amino surface groups were partially (open shell glycodendrimers - OS) or completely (dense shell glycodendrimers - DS) modified with maltose residues. As a model membrane, two types of 100nm diameter liposomes were used to observe differences in the interactions between neutral DMPC and negatively charged DMPC/DMPG bilayers. Interactions were studied using fluorescence spectroscopy to evaluate the membrane fluidity of both the hydrophobic and hydrophilic parts of the lipid bilayer and using differential scanning calorimetry to investigate thermodynamic parameter changes. Pulsed-filed gradient NMR experiments were carried out to evaluate common diffusion coefficient of DMPG and DS PPI in D2O when using below critical micelle concentration of DMPG. Both OS and DS PPI G4 dendrimers show interactions with liposomes. Neutral DS dendrimers exhibit stronger changes in membrane fluidity compared to OS dendrimers. The bilayer structure seems more rigid in the case of anionic DMPC/DMPG liposomes in comparison to pure and neutral DMPC liposomes. Generally, interactions of dendrimers with anionic DMPC/DMPG and neutral DMPC liposomes were at the same level. Higher concentrations of positively charged OS dendrimers induced the aggregation process with negatively charged liposomes. For all types of experiments, the presence of NaCl decreased the strength of the interactions between glycodendrimers and liposomes. Based on NMR diffusion experiments we suggest that apart from electrostatic interactions for OS PPI hydrogen bonds play a major role in maltose-modified PPI dendrimer interactions with anionic and neutral model membranes where a contact surface is needed for undergoing multiple H-bond interactions between maltose shell of glycodendrimers and surface membrane of liposome.

• MeSH
• dendrimery chemie   metabolismus   MeSH
• difenylhexatrien chemie   MeSH
• diferenciální skenovací kalorimetrie MeSH
• dimyristoylfosfatidylcholin chemie   metabolismus   MeSH
• fluidita membrány MeSH
• fluorescenční polarizace MeSH
• fosfatidylglyceroly chemie   metabolismus   MeSH
• hydrofobní a hydrofilní interakce MeSH
• lipidové dvojvrstvy chemie   metabolismus   MeSH
• liposomy chemie   metabolismus   MeSH
• magnetická rezonanční spektroskopie MeSH
• maltosa chemie   metabolismus   MeSH
• membránové lipidy chemie   metabolismus   MeSH
• polypropyleny chemie   metabolismus   MeSH
• statická elektřina MeSH
• vodíková vazba MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Electronic circular dichroism (ECD), absorption and fluorescence spectroscopy were used to study the enantioselective interactions which involved bilirubin (BR), liposomes, human serum albumin of two different purities, pure (HSA) and non-purified of fatty acids (FA-HSA), and individual fatty acids. The application of the ECD technique to such a complex problem provided a new perspective on the BR binding to liposomes. Our results demonstrated that in the presence of pure HSA, BR preferred to bind to the protein over the liposomes. However, in the presence of FA-HSA, BR significantly bound to the liposomes composed either of DMPC or of sphingomyelin and bound only moderately to the primary and secondary binding sites of FA-HSA even at high BR concentrations. For the DMPC liposomes, even a change of BR conformation upon binding to the primary binding site was observed. The individual saturated fatty acids influenced the BR binding to HSA and liposomes in a similar way as fatty acids from FA-HSA. The unsaturated fatty acids interacted with BR alone and prevented it from interacting with either 99-HSA or the liposomes. In the presence of arachidonic acid, BR interacted enantioselectively with the liposomes and only moderately with 99-HSA. Hence, our results show a substantial impact of the liposomes on the BR binding to HSA. As a consequence of the existence of fatty acids in the blood plasma and in the natural structure of HSA, BR may possibly bind to the cell membranes even though it is normally bound to HSA.

• MeSH
• bilirubin metabolismus   MeSH
• cirkulární dichroismus MeSH
• fluorescenční spektrometrie MeSH
• lidé MeSH
• liposomy chemie   MeSH
• mastné kyseliny metabolismus   MeSH
• membrány umělé * MeSH
• sérový albumin metabolismus   MeSH
• spektrofotometrie ultrafialová MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In this study, vibrational circular dichroism (VCD) spectroscopy was employed for the first time to study the bilirubin (BR) interaction with model membranes and models for membrane proteins. An enantioselective interaction of BR with zwitterionic 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and sphingomyelin (SPM) liposomes was observed by VCD and electronic circular dichroism (ECD) complemented by absorption and fluorescence spectroscopy. The M-form of BR was preferentially recognized in the BR/DMPC system at concentration above 1×10(-4)M, for lower concentrations the P-form of BR was recognized by the DMPC liposomes. The VCD spectra also showed that the SPM liposomes, which represent the main component of nerve cell membrane, were significantly more disturbed by the presence of BR than the DMPC liposomes-a stable association with a strong VCD signal was observed providing the explanations for the supposed BR neurotoxicity. The effect of time and pH on the BR/DMPC or SPM liposome systems was shown to be essential while the effect of temperature in the range of 15-70°C was negligible demonstrating the surprisingly high temperature stability of BR when interacting with the studied membranes. The influence of a membrane protein was tested on a model consisting of poly-l-arginine (PLAG) bound in the α-helical form to the surface of 1,2-dimyristoyl-sn-glycero-3-phospho-(1'-rac-glycerol) liposomes and sodium dodecyl sulfate micelles. VCD and also ECD spectra showed that a variety of BR diastereoisomers interacted with PLAG in such systems. In a system of PLAG with micelles composed of sodium dodecyl sulfate, the M-form of bound BR was observed.

• MeSH
• bilirubin chemie   metabolismus   MeSH
• buněčná membrána metabolismus   MeSH
• cholesterol metabolismus   MeSH
• cirkulární dichroismus metody   MeSH
• fluorescenční spektrometrie MeSH
• fosfatidylcholiny metabolismus   MeSH
• lipidové dvojvrstvy chemie   metabolismus   MeSH
• liposomy MeSH
• micely MeSH
• molekulární modely MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Myotonická dystrofia (MD) je geneticky podmienené progresívne degeneratívne ochorenie priečne pruhovaných svalov. Okrem postihnutia svalstva sa fakultatívne vyskytujú viaceré orgánové komplikácie, ktoré postihujú oči, srdce, gonády, endokrinné žľazy a mozog. MD sa v súčasnosti rozdeľuje na dve geneticky odlišné formy. MD1 je zapríčinená expanziou CTG trinukleotidového repetitívneho motívu v géne DMPK, kým expanzia CCTG tetranukleotidového motívu v géne ZNF9 (CNBP) má za následok MD2. Podobné fenotypové prejavy oboch typov MD môžu byť zapríčinené rovnakými molekulárnymi procesmi, ktoré sú spojené pravdepodobne s RNA transkriptmi obsahujúcimi dané expandované trakty. Na druhej strane, odlišnosti medzi MD1 a MD2 môžu byť výsledkom špecifických interakcií CUG a CCUG transkriptov, ako aj lokus špecifických efektov týchto expanzií. Spolu so stále sa rozširujúcimi vedomosťami o patogenických procesoch vedúcich k MD, pribúdajú aj klinické štúdie zamerané na vývoj vhodných liečebných postupov. V starostlivosti o pacientov s MD preto zohrávajú čoraz významnejšiu úlohu metódy vhodné na molekulárnu identifikáciu daných expanzií a vytváranie národných a medzinárodných registrov pacientov s MD.

Myotonic dystrophy (DM) is genetically determined progressive and degenerative disorder of skeletal muscles. Besides involvement of skeletal muscles, DM may cause eye, heart, endocrine and brain disorders. DM comprises at least two genetically distinct forms. DM1 is caused by an expansion of a CTG repeat in the DMPK gene, while expansion of a CCTG repeat in the ZNF9 (CNBP) gene causes DM2. Strikingly similar phenotypic presentations of both types may be a consequence of common pathogenic mechanisms likely connected to the expansion containing RNA transcripts. On the other hand, the differences between DM1 and DM2 may be a consequence of specific interactions of the CUG and CCUG transcripts, and of locus specific effects of these expansions. Together with the extending knowledge about the pathogenic processes leading to DM, there are also a grooving number of clinical studies aimed to find possible therapeutic approaches. Therefore, molecular methods suitable for the direct identification of the expansions and the establishment of national and international patient registries will play crucial role in the healthcare of the patients with DM in the near future.