Katalog - Lichenological literature

24837

Martins M.C.B., Silva M.C., Silva L.R.S., Lima V.L.M., Pereira E.C., Falcão E.P.S., Melo A.M.M.A. & da Silva N.H. (2014): Usnic acid potassium salt: an alternative for the control of Biomphalaria glabrata (Say, 1818), PLoS ONE, 9(11): e111102 [6 p.]

In Brazil, the snail Biomphalaria glabrata is the most important vector of schistosomiasis due to its wide geographical distribution, high infection rate and efficient disease transmission. Among the methods of schistosomiasis control, the World Health Organization recommends the use of synthetic molluscicides, such as niclosamide. However, different substances of natural origin have been tested as alternatives for the control or eradication of mollusks. The literature describes the antitumor, … Read more...

31245

Araújo H.D.A., Aires A.L., Júnior J.G.S., Oliveira J.R.S., Libeiro M.H.M.L., Martins M.C.B., Bezerra M.A.C., Aires A.L., Albuquerque M.C.P.A., Melo-Júnior M.R., Filho N.T.P., Pereira E.C., Silva D.J.R., dos Anjos J.V., Falcão E.P.S., Silva N.H. & Lima V.L.M. (2019): Usnic acid potassium salt: evaluation of the acute toxicity and antinociceptive effect in murine model, Molecules, 24:2042 [17 p.]

To obtain usnic acid potassium salt (PS-UA), the usnic acid (UA) was extracted and purified from the lichen Cladonia substellata, and modified to produce PS-UA. The structure was determined by 1H-NMR, IR and elemental analysis, ratified through computational models, as well as identification the site of K+ insertion in the molecule. Antinociceptive activity was detected through contortions in mice induced by acetic acid and formalin (phases I and II) after treatments with 10 and 20 mg/kg of PS-UA, … Read more...

24424

Su Z.-Q., Mo Z.-Z., Liao J.-B., Feng X.-X., Liang Y.-Z., Zhang X., Liu Y.-H., Chen X.-Y., Chen Z.-W., Su Z.-R. & Lai X.-P. (2014): Usnic acid protects LPS-induced acute lung injury in mice through attenuating inflammatory responses and oxidative stress, International Immunopharmacology, 22(2): 371-378

Usnic acid is a dibenzofuran derivative found in several lichen species, which has been shown to possess several activities, including antiviral, antibiotic, antitumoral, antipyretic, analgesic, antioxidative and anti-inflammatory activities. However, there were few reports on the effects of usnic acid on LPS-induced acute lung injury (ALI). The aim of our study was to explore the effect and possible mechanism of usnic acid on LPS-induced lung injury. In the present study, we found that pretreatment … Read more...

29374

Piska K., Galanty A., Koczurkiewicz P., Żmudzki P., Potaczek J., Podolak I. & Pękala E. (2018): Usnic acid reactive metabolites formation in human, rat, and mice microsomes. Implication for hepatotoxicity, Food and Chemical Toxicology, 120: 112–118

Usnic acid is a lichen compound which is extensively studied due to its cytotoxic, antiproliferative, antimicrobial, antiviral, antiprotozoal, and anti-inflammatory activities. Despite a broad spectrum of biological properties, usnic acid is a hepatotoxic agent, thus its potential use as a drug is limited. Certain hepatotoxic drugs may act by generating reactive metabolites that damage the liver. The aim of the study was to predict the biotransformation of usnic acid enantiomers to reactive products … Read more...

37441

Demir S., Alemdar N.T., Yulug E., Demir E.A., Durmus T.B., Mentese A. & Aliyazicioglu Y. (2024): Usnic acid suppresses inflammation and endoplasmic reticulum stress in a methotrexate-induced pulmonary toxicity model via modulating Nrf2 pathway, South African Journal of Botany, 177: 572–578

Pulmonary toxicity represents a significant adverse effect of methotrexate (MTX), characterised by increased oxidative stress (OS) and inflammation. This study focused on revealing the therapeutic role of usnic acid (UA) against MTX-induced lung injury through biochemical and histological approaches by involving the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. A single dose of MTX was administered to rats to induce pulmonary toxicity, and the therapeutic effect … Read more...

36450

Varli M., Bhosle S.R., Kim E., Yang Y., Tas I., Zhou R., Pulat S., Gamage C.D.B., Park S.Y., Ha H.H. & Kim H. (2024): Usnic Acid Targets 14-3-3 Proteins and Suppresses Cancer Progression by Blocking Substrate Interaction, JACS AU, 4(4): 1521-1537

The anticancer therapeutic effects of usnic acid (UA), a lichen secondary metabolite, have been demonstrated in vitro and in vivo. However, the mechanism underlying the anticancer effect of UA remains to be clarified. In this study, the target protein of UA was identified using a UA-linker-Affi-Gel molecule, which showed that UA binds to the 14-3-3 protein. UA binds to 14-3-3, causing the degradation of proteasomal and autophagosomal proteins. The interaction of UA with 14-3-3 isoforms modulated … Read more...

37780

Sieniawska E., Sawicki R., Truszkiewicz W., Marchev A.S. & Georgiev M.I. (2021): Usnic acid treatment changes the composition of mycobacterium tuberculosis cell envelope and alters bacterial redox status, mSystems, 6(3): e00097

Mycobacterium tuberculosis developed efficient adaptation mechanisms in response to different environmental conditions. This resulted in the ability to survive in human macrophages and in resistance to numerous antibiotics. To get insight into bacterial responses to potent antimycobacterial natural compounds, we tested how usnic acid, a lichen-derived secondary metabolite, would influence mycobacteria at transcriptomic and metabolomic levels. The analysis of expression of sigma factors revealed a … Read more...

35640

Chircov C., Bîrcă A.C., Dănciulescu L.A., Neacșu I.A., Oprea O.-C., Trușcă R.-D. & Andronescu E. (2023): Usnic acid-loaded magnetite nanoparticles—A comparative study between synthesis methods, Molecules, 28(13): 5198 [14 p.]

Since cancer is a continuously increasing concern for the general population, more efficient treatment alternatives ought to be developed. In this regard, a promising direction is represented by the use of magnetite nanoparticles (MNPs) to act both as a nanocarrier for the targeted release of antitumoral drugs and as hyperthermia agents. Thus, the present study focused on improving the control upon the outcome properties of MNPs by using two synthesis methods, namely the co-precipitation and microwave-assisted … Read more...

29136

dos Santos M.R., Alcaraz-Espinoza J.J., da Costa M.M. & de Oliveira H.P. (2018): Usnic acid-loaded polyaniline/polyurethane foam wound dressing: preparation and bactericidal activity, Materials Science and Engineering C, 89: 33–40

The improved bactericidal activity of new composites for wound dressing prototypes represents an important strategy for development of more efficient devices that make use of synergistic interaction between components. The doping level of polyaniline represents a critical parameter for its corresponding biologic activity. In this work, it is explored the doping effect of usnic acid on undoped polyaniline, that introduces important advantages namely, improved bactericidal activity of polyaniline … Read more...

34637

Vasarri M., Ponti L., Degl’Innocenti D. & Bergonzi M.C.C. (2022): Usnic acid-loaded polymeric micelles: An optimal migrastatic-acting formulation in human SH-SY5Y neuroblastoma cells, Pharmaceuticals, 15(10): 1207 [16 p.]

Usnic acid (UA) is one of the most abundant and common metabolites of lichens, known for its numerous pharmacological properties. Nevertheless, it presents some criticalities that severely limit its use in therapy: poor solubility in water and significant hepatotoxicity. Soluplus and Solutol HS15 and D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) were employed to develop polymeric micelles (UA–PM). The chemical and physical properties of the system were characterized, including the size, … Read more...