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Proceedings of the National Academy of... Nov 2022The management of biofilm-related infections is a challenge in healthcare, and antimicrobial photodynamic therapy (aPDT) is a powerful tool that has demonstrated a...
The management of biofilm-related infections is a challenge in healthcare, and antimicrobial photodynamic therapy (aPDT) is a powerful tool that has demonstrated a broad-spectrum activity. Nanotechnology has been used to increase the aPDT effectiveness by improving the photosensitizer's delivery properties. NewPS is a simple, versatile, and safe surfactant-free nanoemulsion with a porphyrin salt shell encapsulating a food-grade oil core with promising photodynamic action. This study evaluated the use of NewPS for aPDT against microorganisms in planktonic, biofilm, and in vivo models of infected wounds. First, the potential of NewPS-mediated aPDT to inactivate and suspensions was evaluated. Then, a series of protocols were assessed against biofilms by means of cell viability and confocal microscopy. Finally, the best biofilm protocol was used for the treatment of in a murine-infected wound model. A high NewPS-bacteria cell interaction was achieved since 0.5 nM and 30 J/cm was able to kill suspension. In the biofilm, enhanced efficacy of NewPS-aPDT was achieved when 100 µM of NewPS was applied with longer periods of incubation at the light dose of 60 J/cm. The best single and double-session protocol reduced 5.56 logs and 6.03 logs, respectively, homogeneous NewPS distribution, resulting in a high number of dead cells after aPDT. The in vivo model showed that one aPDT session enabled a reduction of 6 logs and faster tissue healing than the other groups. In conclusion, NewPS-aPDT may be considered a safe and effective anti-biofilm antimicrobial photosensitizer.
Topics: Mice; Animals; Photochemotherapy; Photosensitizing Agents; Porphyrins; Staphylococcus aureus; Biofilms; Anti-Infective Agents; Anti-Bacterial Agents
PubMed: 36346844
DOI: 10.1073/pnas.2216239119 -
Chemistry (Weinheim An Der Bergstrasse,... Apr 2022Metal complexes of multi-porphyrins and multi-corroles are unique systems that display a host of extremely interesting properties. Availability of free meso and β... (Review)
Review
Metal complexes of multi-porphyrins and multi-corroles are unique systems that display a host of extremely interesting properties. Availability of free meso and β positions allow formation of different types of directly linked bis-porphyrins giving rise to intriguing optical and electronic properties. While the fields of metalloporphyrin and corroles monomer have seen exponential growth in the last decades, the chemistry of metal complexes of bis-porphyrins and bis-corroles remain rather underexplored. Therefore, the impact of covalent linkages on the optical, electronic, (spectro)electrochemical, magnetic and electrocatalytic activities of metal complexes of bis-porphyrins and -corroles has been summarized in this review article. This article shows that despite the (still) somewhat difficult synthetic access to these molecules, their extremely exciting properties do make a strong case for pursuing research on these classes of compounds.
Topics: Coordination Complexes; Metalloporphyrins; Porphyrins
PubMed: 35088477
DOI: 10.1002/chem.202104550 -
Oxidative Medicine and Cellular... 2021Mn(III) --alkyl- and -alkoxyalkyl porphyrins (MnPs) were initially developed as superoxide dismutase (SOD) mimics. These compounds were later shown to react with... (Review)
Review
Mn(III) --alkyl- and -alkoxyalkyl porphyrins (MnPs) were initially developed as superoxide dismutase (SOD) mimics. These compounds were later shown to react with numerous reactive species (such as ONOO, HO, HS, CO , ascorbate, and GSH). Moreover, the ability of MnPs to oxidatively modify activities of numerous proteins has emerged as their major mechanism of action both in normal and in cancer cells. Among those proteins are transcription factors (NF-B and Nrf2), mitogen-activated protein kinases, MAPKs, antiapoptotic bcl-2, and endogenous antioxidative defenses. The lead Mn porphyrins, namely, MnTE-2-PyP (BMX-010, AEOL10113), MnTnBuOE-2-PyP (BMX-001), and MnTnHex-2-PyP, were tested in numerous injuries of normal tissue and cellular and animal cancer models. The wealth of the data led to the progression of MnTnBuOE-2-PyP into four Phase II clinical trials on glioma, head and neck cancer, anal cancer, and multiple brain metastases, while MnTE-2-PyP is in Phase II clinical trial on atopic dermatitis and itch.
Topics: Animals; Antineoplastic Agents; Biological Availability; Humans; Hydrogen Peroxide; Manganese; Porphyrins; Signal Transduction
PubMed: 33815656
DOI: 10.1155/2021/6653790 -
Magnetic Resonance in Medicine Aug 2019CEST has become a preeminent technology for the rapid detection and grading of tumors, securing its widespread use in both laboratory and clinical research. However,...
PURPOSE
CEST has become a preeminent technology for the rapid detection and grading of tumors, securing its widespread use in both laboratory and clinical research. However, many existing CEST MRI agents exhibit a sensitivity limitation due to small chemical shifts between their exchangeable protons and water. We propose a new group of CEST MRI agents, free-base porphyrins and chlorin, with large exchangeable proton chemical shifts from water for enhanced detection.
METHODS
To test these newly identified CEST agents, we acquired a series of Z-spectra at multiple pH values and saturation field strengths to determine their CEST properties. The data were analyzed using the quantifying exchange using saturation power method to quantify exchange rates. After identifying several promising candidates, a porphyrin solution was injected into tumor-bearing mice, and MR images were acquired to assess detection feasibility in vivo.
RESULTS
Based on the Z-spectra, the inner nitrogen protons in free-base porphyrins and chlorin resonate from -8 to -13.5 ppm from water, far shifted from the majority of endogenous metabolites (0-4 ppm) and Nuclear Overhauser enhancements (-1 to -3.5 ppm) and far removed from the salicylates, imidazoles, and anthranillates (5-12 ppm). The exchange rates are sufficiently slow to intermediate (500-9000 s ) to allow robust detection and were sensitive to substituents on the porphyrin ring.
CONCLUSION
These results highlight the capabilities of free-base porphyrins and chlorin as highly upfield CEST MRI agents and provide a new scaffold that can be integrated into a variety of diagnostic or theranostic agents for biomedical applications.
Topics: A549 Cells; Animals; Contrast Media; Humans; Magnetic Resonance Imaging; Mice; Mice, Inbred BALB C; Molecular Imaging; Neoplasms, Experimental; Phantoms, Imaging; Porphyrins; Protons
PubMed: 30968442
DOI: 10.1002/mrm.27753 -
Scientific Reports Sep 2023Oxygenation is a crucial indicator of tissue viability and function. Oxygen tension ([Formula: see text]), i.e. the amount of molecular oxygen present in the tissue is a...
Oxygenation is a crucial indicator of tissue viability and function. Oxygen tension ([Formula: see text]), i.e. the amount of molecular oxygen present in the tissue is a direct result of supply (perfusion) and consumption. Thus, measurement of [Formula: see text] is an effective method to monitor tissue viability. However, tissue oximetry sensors commonly used in clinical practice instead rely on measuring oxygen saturation ([Formula: see text]), largely due to the lack of reliable, affordable [Formula: see text] sensing solutions. To address this issue we present a proof-of-concept design and validation of a low-cost, lifetime-based oxygen sensing fiber. The sensor consists of readily-available off-the shelf components such as a microcontroller, a light-emitting diode (LED), an avalanche photodiode (APD), a temperature sensor, as well as a bright in-house developed porphyrin molecule. The device was calibrated using a benchtop setup and evaluated in three in vivo animal models. Our findings show that the new device design in combination with the bright porphyrin has the potential to be a useful and accurate tool for measuring [Formula: see text] in tissue, while also highlighting some of the limitations and challenges of oxygen measurements in this context.
Topics: Animals; Blood Gas Analysis; Fiber Optic Technology; Oximetry; Oxygen; Porphyrins
PubMed: 37679415
DOI: 10.1038/s41598-023-41917-5 -
Hepatology Communications Oct 2023Bile, which contains bile acids, the natural ligands for farnesoid x receptor (FXR), moves from the liver to the intestine through bile ducts. Ductular reaction often...
BACKGROUND
Bile, which contains bile acids, the natural ligands for farnesoid x receptor (FXR), moves from the liver to the intestine through bile ducts. Ductular reaction often occurs during biliary obstruction. A subset of patients with erythropoietic protoporphyria, an inherited genetic mutation in heme biosynthetic enzyme ferrochelatase, accumulate porphyrin-containing bile plugs, leading to cholestasis. Here, we examined the link between FXR, bile plug formation, and how heme biosynthesis relates to this connection.
METHODS
We treated female and male wild-type and global and tissue-specific Fxr knockout mice with a diet containing 3,5-diethoxycarbonyl-1,4-dihydrocollidine, an inhibitor of ferrochelatase, and examined the expression of heme biosynthetic genes. We mined FXR mouse ChIP-Seq data, performed biochemical and histological analysis, and tested HepG2 and primary human hepatocytes after treatment with obeticholic acid, an FXR agonist.
RESULTS
We observed that hepatic but not intestinal Fxr loss resulted in reduced bile plugs and ductular reaction in the liver. Then, we examined if FXR plays a regulatory role in heme biosynthesis and found significantly lower porphyrin accumulation in 3,5-diethoxycarbonyl-1, 4-dihydrocollidine-fed Fxr knockout mice. Gene expression and FXR mouse ChIP-Seq atlas analysis revealed that FXR orchestrates the expression of multiple heme biosynthetic enzymes. Finally, human HepG2 cells and primary human hepatocytes treated with obeticholic acid, showed increased expression of several heme biosynthetic genes.
CONCLUSIONS
Overall, our data show that hepatic Fxr is necessary to maintain ductular reaction and accumulation of bile plugs. FXR can direct the expression of multiple heme biosynthetic genes. Thus, modulating FXR activity in EPP patients may help alleviate its associated liver disease.
Topics: Animals; Female; Humans; Male; Mice; Cholestasis; Ferrochelatase; Heme; Liver; Porphyrins
PubMed: 37695073
DOI: 10.1097/HC9.0000000000000213 -
Molecules (Basel, Switzerland) Apr 2023Heme , which is characterized by a ferrous ion and a porphyrin macrocycle, acts as a prosthetic group for many enzymes and contributes to various physiological... (Review)
Review
Heme , which is characterized by a ferrous ion and a porphyrin macrocycle, acts as a prosthetic group for many enzymes and contributes to various physiological processes. Consequently, it has wide applications in medicine, food, chemical production, and other burgeoning fields. Due to the shortcomings of chemical syntheses and bio-extraction techniques, alternative biotechnological methods have drawn increasing attention. In this review, we provide the first systematic summary of the progress in the microbial synthesis of heme . Three different pathways are described in detail, and the metabolic engineering strategies for the biosynthesis of heme via the protoporphyrin-dependent and coproporphyrin-dependent pathways are highlighted. The UV spectrophotometric detection of heme is gradually being replaced by newly developed detection methods, such as HPLC and biosensors, and for the first time, this review summarizes the methods used in recent years. Finally, we discuss the future prospects, with an emphasis on the potential strategies for improving the biosynthesis of heme and understanding the regulatory mechanisms for building efficient microbial cell factories.
Topics: Heme; Biosynthetic Pathways; Porphyrins; Metabolic Engineering
PubMed: 37110868
DOI: 10.3390/molecules28083633 -
Chembiochem : a European Journal of... Jun 2021We report the application of a highly versatile and engineerable novel sensor platform to monitor biologically significant and toxic metal ions in live human Caco-2...
We report the application of a highly versatile and engineerable novel sensor platform to monitor biologically significant and toxic metal ions in live human Caco-2 enterocytes. The extended conjugation between the fluorescent porphyrin core and metal ions through aromatic phenylphosphonic acid tethers generates a unique turn off and turn on fluorescence and, in addition, shifts in absorption and emission spectra for zinc, cobalt, cadmium and mercury. The reported fluorescent probes p-H TPPA and m-H TPPA can monitor a wide range of metal ion concentrations via fluorescence titration and also via fluorescence decay curves. Cu- and Zn-induced turn off fluorescence can be differentially reversed by the addition of common chelators. Both p-H TPPA and m-H TPPA readily pass the mammalian cellular membrane due to their amphipathic character as confirmed by confocal microscopic imaging of living enterocytes.
Topics: Caco-2 Cells; Coordination Complexes; Enterocytes; Fluorescence; Fluorescent Dyes; Humans; Metals, Heavy; Organophosphonates; Porphyrins
PubMed: 33554446
DOI: 10.1002/cbic.202100031 -
Accounts of Chemical Research Dec 2021Heme proteins have proven to be a convenient platform for the development of designer proteins with novel functionalities. This is achieved by substituting the native...
Heme proteins have proven to be a convenient platform for the development of designer proteins with novel functionalities. This is achieved by substituting the native iron porphyrin cofactor with a heme analogue that possesses the desired properties. Replacing the iron center of the porphyrin with another metal provides one inroad to novel protein function. A less explored approach is substitution of the porphyrin cofactor with an alternative tetrapyrrole macrocycle or a related ligand. In general, these ligands exhibit chemical properties and reactivity that are distinct from those of porphyrins. While these techniques have most prominently been utilized to develop artificial metalloenzymes, there are many other applications of this methodology to problems in biochemistry, health, and medicine. Incorporation of synthetic cofactors into protein environments represents a facile way to impart water solubility and biocompatibility. It circumvents the laborious synthesis of water-soluble cofactors, which often introduces substantial charge that leads to undesired bioaccumulation. To this end, the incorporation of unnatural cofactors in heme proteins has enabled the development of designer proteins as optical oxygen sensors, MRI contrast agents, spectroscopic probes, tools to interrogate protein function, antibiotics, and fluorescent proteins.Incorporation of an artificial cofactor is frequently accomplished by denaturing the holoprotein with removal of the heme; the refolded apoprotein is then reconstituted with the artificial cofactor. This process often results in substantial protein loss and does not necessarily guarantee that the refolded protein adopts the native structure. To circumvent these issues, our laboratory has pioneered the use of the RP523 strain of to incorporate artificial cofactors into heme proteins using expression-based methods. This strain lacks the ability to biosynthesize heme, and the bacterial cell wall is permeable to heme and related molecules. In this way, heme analogues supplemented in the growth medium are incorporated into heme proteins. This approach can also be leveraged for the direct expression of the apoprotein for subsequent reconstitution.These methodologies have been exploited to incorporate non-native cofactors into heme proteins that are resistant to harsh environmental conditions: the heme nitric oxide/oxygen binding protein (H-NOX) from () and the heme acquisition system protein A (HasA) from (). The exceptional stability of these proteins makes them ideal scaffolds for biomedical applications. Optical oxygen sensing has been accomplished using a phosphorescent ruthenium porphyrin as the artificial heme cofactor. Paramagnetic manganese and gadolinium porphyrins yield high-relaxivity, protein-based MRI contrast agents. A fluorescent phosphorus corrole serves as a heme analogue to produce fluorescent proteins. Iron complexes of nonporphyrin cofactors bound to HasA inhibit the growth of pathogenic bacteria. Moreover, HasA can deliver a gallium phthalocyanine into the bacterial cytosol to serve as a sensitizer for photochemical sterilization. Together, these examples illustrate the potential for designer heme proteins to address burgeoning problems in the areas of health and medicine. The concepts and methodologies presented in this Account can be extended to the development of next-generation biomedical sensing and imaging agents to identify and quantify clinically relevant metabolites and other key disease biomarkers.
Topics: Escherichia coli; Heme; Hemeproteins; Metalloproteins; Metals
PubMed: 34890183
DOI: 10.1021/acs.accounts.1c00588 -
Molecules (Basel, Switzerland) Feb 2022The use of nanoparticles has been investigated as a new cancer treatment. These can induce specific cytotoxicity in cancer cells. In particular, Au nanoparticles (AuNPs)...
The use of nanoparticles has been investigated as a new cancer treatment. These can induce specific cytotoxicity in cancer cells. In particular, Au nanoparticles (AuNPs) have unique characteristics. The maximum absorption spectrum of AuNPs can be adjusted to modify their size or shape to absorb near-infrared light that can penetrate into tissue without photodamage. Thus, the combination of AuNPs and near-infrared light can be used to treat cancer in deep-seated organs. To obtain effective cancer-specific accumulation of AuNPs, we focused on porphyrin and synthesized a porphyrin-attached Au compound: Au-HpD. In this study, we investigated whether Au-HpD possesses cancer-specific accumulation and cytotoxicity. Intracellular Au-HpD accumulation was higher in cancer cells than in normal cells. In order to analyze the cytotoxicity induced by Au-HpD, cancer cells and normal cells were co-cultured in the presence of Au-HpD; then, they were subjected to 870 nm laser irradiation. We observed that, after laser irradiation, cancer cells showed significant morphological changes, such as chromatin condensation and nuclear fragmentation indicative of cell apoptosis. This strong effect was not observed when normal cells were irradiated. Moreover, cancer cells underwent cell apoptosis with combination therapy.
Topics: Apoptosis; Cell Line, Tumor; Gold; Humans; Infrared Rays; Metal Nanoparticles; Neoplasms; Phototherapy; Porphyrins
PubMed: 35209026
DOI: 10.3390/molecules27041238