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Amino Acids Jun 2024Plasma total cysteine (tCys) is strongly associated with fat mass in humans. Mesna lowers plasma tCys in a dose-dependent manner, but it is not known whether it... (Randomized Controlled Trial)
Randomized Controlled Trial
Plasma total cysteine (tCys) is strongly associated with fat mass in humans. Mesna lowers plasma tCys in a dose-dependent manner, but it is not known whether it interferes with metabolism of other amino acids or protein. In this Phase-1 study, we show that a single dose of mesna administered at 400, 800, 1200 or 1600 mg to 6-7 individuals per dose only slightly affects amino acid profiles, with increases in plasma valine across dose levels. There were no effects of mesna on 3-methylhistidine, a marker of protein breakdown.
Topics: Humans; Male; Female; Administration, Oral; Dose-Response Relationship, Drug; Methylhistidines; Adult; Amino Acids; Cysteine; Middle Aged
PubMed: 38844567
DOI: 10.1007/s00726-024-03398-2 -
International Journal of Pharmaceutics May 2024This study aims to design chemically crosslinked thiolated cyclodextrin-based hydrogels and to evaluate their mucoadhesive properties via mucosal residence time studies...
AIM
This study aims to design chemically crosslinked thiolated cyclodextrin-based hydrogels and to evaluate their mucoadhesive properties via mucosal residence time studies on porcine small intestinal mucosa and on porcine buccal mucosa.
METHODS
Free thiol groups of heptakis(6-deoxy-6-thio)-β-cyclodextrin (β-CD-SH) were S-protected with 2-mercaptoethanesulfonic acid (MESNA) followed by crosslinking with citric acid. Cytotoxicity was assessed by hemolysis as well as resazurin assay. Hydrogels were characterized by their rheological and mucoadhesive properties. Ritonavir was employed as model drug for in vitro release studies from these hydrogels.
RESULTS
The structure of S-protected β-CD-SH was confirmed by IR and H NMR spectroscopy. Degree of thiolation was 390 ± 7 µmol/g. Hydrogels based on native β-CD showed hemolysis of 12.5 ± 2.5 % and 13.6 ± 2.7 % within 1 and 3 h, whereas hemolysis of just 3.5 ± 2.8 % and 3.9 ± 3.0 % was observed for the S-protected thiolated CD hydrogels, respectively. Both native and S-protected thiolated hydrogels showed minor cytotoxicity on Caco-2 cells. Rheological investigations of S-protected thiolated β-CD-based hydrogel (16.2 % m/v) showed an up to 13-fold increase in viscosity in contrast to the corresponding native β-CD-based hydrogel. Mucosal residence time studies showed that thiolated β-CD-based hydrogel is removed to a 16.6- and 2.4-fold lower extent from porcine small intestinal mucosa and porcine buccal mucosa in comparision to the native β-CD-based hydrogel, respectively. Furthermore, a sustained release of ritonavir from S-protected thiolated β-CD-based hydrogels was observed.
CONCLUSION
Because of their comparatively high mucoadhesive and release-controlling properties, S-protected thiolated β-CD-based hydrogels might be promising systems for mucosal drug delivery.
Topics: Hydrogels; Animals; Humans; Caco-2 Cells; Swine; Sulfhydryl Compounds; Mouth Mucosa; beta-Cyclodextrins; Intestinal Mucosa; Rheology; Hemolysis; Adhesiveness; Drug Liberation; Polymers; Cell Survival; Intestine, Small
PubMed: 38599445
DOI: 10.1016/j.ijpharm.2024.124075 -
Cureus Feb 2024Polyarteritis nodosa (PAN) is a connective tissue disease that affects arteries, causing necrotizing inflammation that can weaken the arterial walls, dilatation into...
Polyarteritis nodosa (PAN) is a connective tissue disease that affects arteries, causing necrotizing inflammation that can weaken the arterial walls, dilatation into aneurysms, and rupture in some cases. We present a case of a male with acute abdomen from aneurysmal rupture. The 48-year-old patient with a history of polysubstance use including cocaine and methamphetamines was admitted for acute hypoxic respiratory failure secondary to coronavirus disease 2019 (COVID-19) pneumonia and treated with broad-spectrum antibiotics and steroids. He also reported generalized abdominal pain and discomfort, and examination revealed abdominal distension that was diffusely tender on palpation, bowel sounds intact. Laboratory workup showed a progressive drop in hemoglobin requiring blood transfusions, no coagulopathy, anion gap metabolic acidosis, and lactic acidosis. Abdominal CT showed a 2 cm lobulated saccular aneurysm involving either the left gastric artery or splenic artery, associated with an extensive moderate amount of hemoperitoneum with hematomas (largest measuring up to 8.6 cm) abutting the gastric fundus and greater curvature of the stomach, which was likely secondary to aneurysmal rupture. Additionally, several other mesenteric vessels displayed some degree of dilation. Interventional radiology (IR)-guided splenic artery embolization for splenic artery aneurysm was done, after which his hemoglobin remained stable. The patient was given vaccine recommendations since splenic artery embolization would lead to asplenia. The aneurysms were attributed to either cocaine-related aneurysms or polyarteritis nodosa with visceral artery aneurysms. He denied rashes, oral ulcers, joint pain, subcutaneous nodules, blood in the urine, history of hepatitis or syphilis. Tertiary syphilis was ruled out after the Venereal Disease Research Laboratory (VDRL) test and rapid plasma reagin (RPR) test were negative. Complement C3 and C4 levels were normal. He was treated with high-dose IV methylprednisone after infection was ruled out. Due to the severity of PAN, therapy with IV cyclophosphamide therapy 15 mg/kg once every two weeks for three doses was initiated, followed by 15 mg/kg once every three weeks for three to six months (in combination with glucocorticoids prednisone 1 mg/kg body weight with slow taper). Cyclophosphamide was given with IV hydration and mesna. The presentation of PAN can vary widely. Most commonly, individuals experience symptoms such as fatigue, weight loss, fever, and chills. However, in rare cases, patients may present with isolated abdominal pain, similar to our patient. It's crucial to note that the rupture of an aneurysm can manifest as an acute abdominal issue, potentially leading to life-threatening situations. Immediate interventions to control bleeding are imperative in such cases. The treatment of PAN has a high success rate when a combination of cyclophosphamide and steroids is administered.
PubMed: 38558645
DOI: 10.7759/cureus.55143 -
Proceedings of the National Academy of... Apr 2024Methanogenic archaea inhabiting anaerobic environments play a crucial role in the global biogeochemical material cycle. The most universal electrogenic reaction of their...
Methanogenic archaea inhabiting anaerobic environments play a crucial role in the global biogeochemical material cycle. The most universal electrogenic reaction of their methane-producing energy metabolism is catalyzed by -methyl-tetrahydromethanopterin: coenzyme M methyltransferase (MtrABCDEFGH), which couples the vectorial Na transport with a methyl transfer between the one-carbon carriers tetrahydromethanopterin and coenzyme M via a vitamin B derivative (cobamide) as prosthetic group. We present the 2.08 Å cryo-EM structure of Mtr(ABCDEFG) composed of the central Mtr(ABFG) stalk symmetrically flanked by three membrane-spanning MtrCDE globes. Tetraether glycolipids visible in the map fill gaps inside the multisubunit complex. Putative coenzyme M and Na were identified inside or in a side-pocket of a cytoplasmic cavity formed within MtrCDE. Its bottom marks the gate of the transmembrane pore occluded in the cryo-EM map. By integrating Alphafold2 information, functionally competent MtrA-MtrH and MtrA-MtrCDE subcomplexes could be modeled and thus the methyl-tetrahydromethanopterin demethylation and coenzyme M methylation half-reactions structurally described. Methyl-transfer-driven Na transport is proposed to be based on a strong and weak complex between MtrCDE and MtrA carrying vitamin B, the latter being placed at the entrance of the cytoplasmic MtrCDE cavity. Hypothetically, strongly attached methyl-cob(III)amide (His-on) carrying MtrA induces an inward-facing conformation, Na flux into the membrane protein center and finally coenzyme M methylation while the generated loosely attached (or detached) MtrA carrying cob(I)amide (His-off) induces an outward-facing conformation and an extracellular Na outflux. Methyl-cob(III)amide (His-on) is regenerated in the distant active site of the methyl-tetrahydromethanopterin binding MtrH implicating a large-scale shuttling movement of the vitamin B-carrying domain.
Topics: Mesna; Methyltransferases; Methylation; Vitamin B 12; Methane; Amides; Vitamins
PubMed: 38530900
DOI: 10.1073/pnas.2315568121 -
Journal of Functional Biomaterials Feb 2024"Hot spot" F magnetic resonance imaging (MRI) has garnered significant attention recently for its ability to image various disease markers quantitatively. Unlike...
"Hot spot" F magnetic resonance imaging (MRI) has garnered significant attention recently for its ability to image various disease markers quantitatively. Unlike conventional gadolinium-based MRI contrast agents, which rely on proton signal modulation, F-MRI's direct detection has a unique advantage in vivo, as the human body exhibits a negligible background F-signal. However, existing perfluorocarbon (PFC) or PFC-based contrast materials suffer from several limitations, including low longitudinal relaxation rates and relatively low imaging efficiency. Hence, we designed a macromolecular contrast agent featuring a high number of magnetically equivalent F-nuclei in a single macromolecule, adequate fluorine nucleus mobility, and excellent water solubility. This design utilizes superfluorinated polyphosphazene (PPz) polymers as the F-source; these are modified with sodium mercaptoethanesulfonate (MESNa) to achieve water solubility exceeding 360 mg/mL, which is a similar solubility to that of sodium chloride. We observed substantial signal enhancement in MRI with these novel macromolecular carriers compared to non-enhanced surroundings and aqueous trifluoroacetic acid (TFA) used as a positive control. In conclusion, these novel water-soluble macromolecular carriers represent a promising platform for future MRI contrast agents.
PubMed: 38391893
DOI: 10.3390/jfb15020040 -
The ISME Journal Jan 2024Hadarchaeota inhabit subsurface and hydrothermally heated environments, but previous to this study, they had not been cultured. Based on metagenome-assembled genomes,...
Hadarchaeota inhabit subsurface and hydrothermally heated environments, but previous to this study, they had not been cultured. Based on metagenome-assembled genomes, most Hadarchaeota are heterotrophs that grow on sugars and amino acids, or oxidize carbon monoxide or reduce nitrite to ammonium. A few other metagenome-assembled genomes encode alkyl-coenzyme M reductases (Acrs), β-oxidation, and Wood-Ljungdahl pathways, pointing toward multicarbon alkane metabolism. To identify the organisms involved in thermophilic oil degradation, we established anaerobic sulfate-reducing hexadecane-degrading cultures from hydrothermally heated sediments of the Guaymas Basin. Cultures at 70°C were enriched in one Hadarchaeon that we propose as Candidatus Cerberiarchaeum oleivorans. Genomic and chemical analyses indicate that Ca. C. oleivorans uses an Acr to activate hexadecane to hexadecyl-coenzyme M. A β-oxidation pathway and a tetrahydromethanopterin methyl branch Wood-Ljungdahl (mWL) pathway allow the complete oxidation of hexadecane to CO2. Our results suggest a syntrophic lifestyle with sulfate reducers, as Ca. C. oleivorans lacks a sulfate respiration pathway. Comparative genomics show that Acr, mWL, and β-oxidation are restricted to one family of Hadarchaeota, which we propose as Ca. Cerberiarchaeaceae. Phylogenetic analyses further indicate that the mWL pathway is basal to all Hadarchaeota. By contrast, the carbon monoxide dehydrogenase/acetyl-coenzyme A synthase complex in Ca. Cerberiarchaeaceae was horizontally acquired from Bathyarchaeia. The Acr and β-oxidation genes of Ca. Cerberiarchaeaceae are highly similar to those of other alkane-oxidizing archaea such as Ca. Methanoliparia and Ca. Helarchaeales. Our results support the use of Acrs in the degradation of petroleum alkanes and suggest a role of Hadarchaeota in oil-rich environments.
Topics: Anaerobiosis; Phylogeny; Mesna; Alkanes; Oxidation-Reduction; Oxidoreductases; Sulfates
PubMed: 38365230
DOI: 10.1093/ismejo/wrad004 -
ACS Omega Feb 2024This study aimed at designing an S-protected thiolated β-cyclodextrin (β-CD) exhibiting enhanced mucoadhesive properties. The native β-CD was thiolated with...
This study aimed at designing an S-protected thiolated β-cyclodextrin (β-CD) exhibiting enhanced mucoadhesive properties. The native β-CD was thiolated with phosphorus pentasulfide resulting in a thiolated β-CD (β-CD-SH) and subsequently S-protected with 2-mercaptoethanesulfonate (MESNA) to form β-CD-SS-MESNA. The structure of the novel excipient was confirmed by H NMR and Fourier-transform infrared spectroscopy. The sulfhydryl content of β-CD-SH, determined by Ellman's test, was 2281.00 ± 147 μmol/g, and it was decreased to 45.93 ± 19.40 μmol/g by S-protection. Due to thiolation and S-protection, the viscosity of the mixture of mucus with β-CD-SH and β-CD-SS-MESNA increased 1.8 and 4.1-fold, compared to native β-CD, respectively. The unprotected β-CD-SH diffused to a lesser extent into the mucus than native β-CD, while S-protected β-CD-SS-MESNA showed the highest mucodiffusion among the applied CDs. A 1.5- and 3.0-fold higher cellular uptake of β-CD-SH and β-CD-SS-MESNA, compared to the native one, was established on Caco-2 cell line by flow cytometry, respectively, causing slightly decreased cell viability. On account of the enhanced mucoadhesion, this higher cellular uptake does not affect the application potential of β-CD-SS-MESNA as an oral drug delivery system since the carrier remains in the mucus and does not reach the underlying epithelial layer. According to these results, the S-protection of β-CD-SH with MESNA promotes improved mucodiffusion, strong mucoadhesion, and prolonged mucosal residence time.
PubMed: 38343993
DOI: 10.1021/acsomega.3c08836 -
Otolaryngologia Polska = the Polish... Feb 2024<b><br>Introduction:</b> 'Off-label drug use' refers to the administration of drugs for unapproved indications or age groups, a different dosage or...
<b><br>Introduction:</b> 'Off-label drug use' refers to the administration of drugs for unapproved indications or age groups, a different dosage or other form of administration. Considering the legal issues, there clearly exists a need to implement rules that would regulate the use of pharmaceuticals outside the scope of a marketing authorisation. The brevity and diversity of Polish laws in the field of health care leads to many interpretative doubts associated with particular legal acts.</br> <b><br>Aim:</b> We aimed to present clinical examples from everyday practice of off-label drug use from the medical and legal perspectives, and to support it with relevant legal acts.</br> <b><br>Material and method:</b> Off-label drug use in various otolaryngology subspecialties - otology (mesna), laryngology (bevacizumab, cidofovir and botulinum toxin) and head and neck surgery (botulinum toxin) - are presented and discussed in detail.</br> <b><br>Results:</b> Fourteen Polish legal acts regarding off-label drug use and 4 from EU legislation are commented on. The algorithm of cascade of decision-making processes in off-label drug use is shown.</br> <b><br>Conclusions:</b> Off-label use of medicinal products is not prohibited in Poland or the EU; nevertheless, it is undeniable that the unclear legal situation regarding the use of medicinal products for nonregistered indications creates difficulties. To minimise a doctor's liability risk, obtaining the informed consent from the patient for such treatment is advisable.</br>.
Topics: Humans; Off-Label Use; Poland; Bevacizumab; Botulinum Toxins; Otolaryngology
PubMed: 38332710
DOI: 10.5604/01.3001.0054.1185 -
Frontiers in Veterinary Science 2023Feline idiopathic cystitis is a common, chronic-relapsing disorder of the lower urinary tract. In addition to environmental modification/enrichment, long-term and safe...
Uroprotective and pain-relieving effect of dietary supplementation with micronized palmitoyl-glucosamine and hesperidin in a chronic model of cyclophosphamide-induced cystitis.
INTRODUCTION
Feline idiopathic cystitis is a common, chronic-relapsing disorder of the lower urinary tract. In addition to environmental modification/enrichment, long-term and safe treatment targeting specific pathophysiological changes may be of help. In this context, effective dietary interventions hold clinical promise. Palmitoyl-glucosamine (PGA) and hesperidin (HSP) are safe and authorized feed ingredients for animal nutrition under European regulations.
METHODS
The current study aimed to investigate whether a 3:1 mixture of micronized PGA and HSP could represent a novel mechanism-oriented approach to chronic cystitis management. A newly validated rat model of cyclophosphamide (CYP)-induced chronic cystitis was used (40 mg/kg, three intraperitoneal injections every 3rd day). Animals were randomized to orally receive either vehicle or PGA-HSP at a low (72 + 24 mg/kg) or high (doubled) dose for 13 days, starting 3 days before the chronic CYP protocol, with mesna (2-mercaptoethane-sulfonate) being used as a reference drug.
RESULTS
Higher PGA-HSP dose was effective at relieving chronic visceral pain, as measured by mechanical allodynia test (von Frey test). The severity of cystitis was also significantly improved, as shown by the reduced sonographic thickening of the bladder wall, as well as the decrease in edema, bleeding and bladder to body weight ratio compared to the vehicle treated group. A significant decrease of MPO activity, MDA level and fibrosis at Masson's trichrome staining was also observed in animals administered PGA-HSP in comparison to vehicle treated ones. The CYP-induced increase in bladder mRNA expression of pro-inflammatory cytokines was also significantly counteracted by the study mixture. Moreover, CYP-induced bladder mast cell accumulation and releasability were significantly decreased by PGA-HSP (even at the low dose), as determined by metachromatic staining, chymase and tryptase immunostaining as well as enzyme-linked immunosorbent assay for histamine and 5-hydoxytriptamine.
DISCUSSION
PGA-HSP is able to block CYP-induced decrease of tight junction proteins, claudin-1 and occludin, thus preserving the urothelial bladder function. Finally, neuroinflammatory changes were investigated, showing that dietary supplementation with PGA-HSP prevented the activation of neurons and non-neuronal cells (i.e., microglia, astrocytes and mast cells) at the spinal level, and counteracted CYP-induced increase of spinal mRNA encoding for pro-inflammatory cytokines. Altogether, the present findings confirm the uroprotective and pain-relieving effect of PGA-HSP and pave the way to potential and relevant clinical applications of the study supplement in feline idiopathic cystitis.
PubMed: 38249555
DOI: 10.3389/fvets.2023.1327102