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1.
Front Med (Lausanne) ; 9: 851782, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35712111

RESUMO

The natural clinoptilolite material is an inorganic crystal mineral called zeolite. It has been extensively studied and used in industrial applications and veterinary and human medicine due to positive effects on health. Limited data is available in the scientific literature about its effects on the levels of physiologically relevant minerals in the human organism. Accordingly, we performed a comprehensive and controlled monitoring of the relevant mineral and contaminants levels in human subjects supplemented with a certified clinoptilolite material within three clinical trials with different supplementation regimens. Effects of a registered and certified clinoptilolite material PMA-zeolite on selected mineral and metal levels were determined by standard biochemical methods and inductively coupled plasma mass spectrometry (ICP-MS) in the blood of subjects enrolled in three clinical trials: short-term (28 days, Mineral Metabolism and selected Blood Parameters study MMBP), medium-term (12 weeks, Morbus Crohn study), and long-term (4 years, Osteoporosis TOP study) supplementation. Lower concentrations were observed for copper (Cu) in patients with osteoporosis, which normalized again in the long-term supplementation trial, whereas sodium (Na) and calcium (Ca) levels diminished below the reference values in patients with osteoporosis. In the short- and long-term supplementation trials, increased levels of lead (Pb) were observed in PMA-zeolite-supplemented subjects, which decreased in the continued long-term supplementation trial. Increased levels of aluminum (Al) or Pb attributable to eventual leakage from the material into the bloodstream were not detected 1 h after intake in the short-term supplementation trial. Nickel (Ni) and Al were statistically significantly decreased upon long-term 4-year supplementation within the long-term supplementation trial, and arsenic (As) was statistically significantly decreased upon 12-weeks supplementation in the medium-term trial. Alterations in the measured levels for Na and Ca, as well as for Pb, in the long-term trial are probably attributable to the bone remodeling process. Checking the balance of the minerals Cu, Ca, and Na after 1 year of supplementation might be prescribed for PMA-supplemented patients with osteoporosis. Clinical Trial Registration: [https://clinicaltrials.gov], identifiers [NCT03901989, NCT05178719, NCT04370535, NCT04607018].

2.
Molecules ; 26(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684777

RESUMO

Zeolites and zeolitic imidazolate frameworks (ZIFs) are widely studied as drug carrying nanoplatforms to enhance the specificity and efficacy of traditional anticancer drugs. At present, there is no other systematic review that assesses the potency of zeolites/ZIFs as anticancer drug carriers. Due to the porous nature and inherent pH-sensitive properties of zeolites/ZIFs, the compounds can entrap and selectively release anticancer drugs into the acidic tumor microenvironment. Therefore, it is valuable to provide a comprehensive overview of available evidence on the topic to identify the benefits of the compound as well as potential gaps in knowledge. The purpose of this study was to evaluate the potential therapeutic applications of zeolites/ZIFs as drug delivery systems delivering doxorubicin (DOX), 5-fluorouracil (5-FU), curcumin, cisplatin, and miR-34a. Following PRISMA guidelines, an exhaustive search of PubMed, Scopus, Embase, and Web of Science was conducted. No language or time limitations were used up to 25th August 2021. Only full text articles were selected that pertained to the usage of zeolites/ZIFs in delivering anticancer drugs. Initially, 1279 studies were identified, of which 572 duplicate records were excluded. After screening for the title, abstract, and full texts, 53 articles remained and were included in the qualitative synthesis. An Inter-Rater Reliability (IRR) test, which included a percent user agreement and reliability percent, was conducted for the 53 articles. The included studies suggest that anticancer drug-incorporated zeolites/ZIFs can be used as alternative treatment options to enhance the efficacy of cancer treatment by mitigating the drawbacks of drugs under conventional treatment.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Zeolitas , Animais , Antineoplásicos/farmacocinética , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Portadores de Fármacos/química , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Nanopartículas/química , Neoplasias/metabolismo , Porosidade , Células Tumorais Cultivadas , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/fisiologia , Zeolitas/química
3.
Exp Biol Med (Maywood) ; 246(5): 529-537, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33183068

RESUMO

The severity of osteoporosis in humans manifests in its high incidence and by its complications that diminish quality of life. A societal consequence of osteoporosis is the substantial burden that it inflicts upon patients and their families. Several bone-modifying drugs have been prescribed to patients with osteoporosis. However, evidence for their anti-fracture efficacy remains inconclusive. To the contrary, long-term use of anti-osteoporotic drugs such as bisphosphonates and Denosumab, an RANKL inhibitor, have resulted in adverse events. We now present an alternative and adjuvant approach for treatment of osteoporosis. The data derive from in vivo studies in an ovariectomized rat model and from a randomized double blind, placebo-controlled human clinical study. Both studies involved treatment with Panaceo Micro Activation (PMA)-zeolite-clinoptilolite, a defined cation exchange clinoptilolite, which clearly improved all bone histomorphometric parameters examined from ovariectomized animals, indicative for increased bone formation. Moreover, intervention with PMA-zeolite-clinoptilolite for one year proved safe in humans. Furthermore, patients treated with PMA-zeolite-clinoptilolite showed an increase in bone mineral density, an elevated level of markers indicative of bone formation, a significant reduction in pain, and significantly improved quality of life compared with patients in the control (placebo) group. These encouraging positive effects of PMA-zeolite-clinoptilolite on bone integrity and on osteoporosis warrant further evaluation of treatment with PMA-zeolite-clinoptilolite as a new alternative adjuvant therapy for osteoporosis.


Assuntos
Osteoporose/tratamento farmacológico , Zeolitas/uso terapêutico , Idoso , Animais , Biomarcadores/metabolismo , Densidade Óssea/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Osteoporose/patologia , Osteoporose/fisiopatologia , Ovariectomia , Ratos Wistar , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos , Tíbia/patologia , Tíbia/fisiopatologia , Microtomografia por Raio-X , Zeolitas/farmacologia
4.
Molecules ; 25(9)2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32397337

RESUMO

Nutrigenomics is a discipline that studies the effects of various dietary components on gene expression and molecular mechanisms via "omics" technologies. Many studies are focused on revealing the pathways of the anticancer properties of various nutraceuticals. However, it has been shown that metastasis, a multifactorial disease that develops from primary tumors in cascades, is responsible for almost 90% of cancer deaths. Regrettably, the effects of consumption of different nutraceuticals on metastasis development have not yet been sufficiently explored. A few studies on the subject have revealed the promotional effects of some nutraceuticals on metastasis development. Additionally, it has been shown that certain compounds can have beneficial effects on reduction of the primary tumor, but afterwards promote the spread of metastases. Therefore, in this review we discuss results published in the past five years focused on the effects of different nutraceuticals on metastasis development.


Assuntos
Suplementos Nutricionais/efeitos adversos , Neoplasias/metabolismo , Humanos , Metástase Neoplásica , Neoplasias/patologia
5.
Bioorg Med Chem ; 20(11): 3675-85, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22555152

RESUMO

Several novel 1,2,4-triazole and imidazole L-ascorbic acid (1, 2, 3, 5, 6 and 9) and imino-ascorbic acid (4, 7 and 8) derivatives were prepared and evaluated for their inhibitory activity against hepatitis C virus (HCV) replication and human tumour cell proliferation. Compounds 6 and 9 exerted the most pronounced cytostatic effects in all tumour cell lines tested, and were highly selective for human T-cell acute lymphoblastic leukaemia cells (CEM/0) with IC(50)s of 10 ± 4 and 7.3 ± 0.1 µM, respectively. Unlike compound 9, compound 6 showed no toxicity in human diploid fibroblasts. One of the possible mechanisms of action of compound 6 accounting for observed cytostatic activity towards haematological malignancies might be inhibition of inosine monophosphate dehydrogenase (IMPDH) activity, a key enzyme of de novo purine nucleotide biosynthesis providing the cells with precursors for DNA and RNA synthesis indispensable for cell growth and division, which has emerged as an important target for antileukemic therapy. In addition, this compound proved to be the most potent inhibitor of the hepatitis C virus replication as well. However, observed antiviral effect was most likely associated with the effect that the compound exerted on the host cell rather than with selective effect on the replication of the virus itself. In conclusion, results of this study put forward compound 6 as a potential novel antitumor agent (IMPDH inhibitor) for treating leukaemia. Its significant biological activity and low toxicity in human diploid fibroblasts encourage further development of this compound as a lead.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antivirais/síntese química , Antivirais/farmacologia , Ácido Ascórbico/análogos & derivados , Hepacivirus/efeitos dos fármacos , Imidazóis/química , Triazóis/química , Animais , Antineoplásicos/química , Antivirais/química , Ácido Ascórbico/química , Linhagem Celular Tumoral , Cães , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Fibroblastos/efeitos dos fármacos , Hepacivirus/fisiologia , Humanos , IMP Desidrogenase/antagonistas & inibidores , Imidazóis/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Replicação Viral/efeitos dos fármacos
6.
Antivir Chem Chemother ; 21(6): 221-30, 2011 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-21730369

RESUMO

BACKGROUND: Several published studies indicate that the acyclic guanine nucleoside analogues possessing bis(1,2-hydroxymethyl) substituted cyclopropane rings mimicking the sugar moiety are potent inhibitors of replication of several herpes viruses. METHODS: Established synthetic methods and antiviral and cytostatic activity assays were used for the evaluation of new 1,2,4-triazole and purine acyclic nucleoside analogues. RESULTS: The synthesis of new types of acyclic nucleoside analogues which incorporate 1,2,4-triazole or purine moiety bound via flexible methylenic spacer to the bis(1,2-hydroxymethyl) cyclopropane ring. None of the new compounds showed pronounced antiviral activities at subtoxic concentrations on a broad panel of DNA and RNA viruses. Evaluation of their affinity for herpes simplex type 1 (HSV-1) and varicella-zoster virus-encoded thymidine kinases (VZV TK) also showed that none of the compounds was able to significantly inhibit 1 µM deoxythymidine phosphorylation by HSV-1 and VZV TK at 500 µM concentrations. The in vitro cytostatic activity evaluation results indicated a weak antiproliferative activity for all tested compounds. Only 6-pyrrolylpurine derivative bearing a carboxylic group substituted cyclopropane ring produced a rather slight inhibitory effect at higher micromolar concentrations on a breast carcinoma cell line (MCF-7) and no cytotoxic effect on human normal fibroblasts (WI 38). CONCLUSIONS: The lack of antiherpetic activity may be due to poor, if any, recognition of the compounds by virus-induced nucleoside kinases as an alternative substrate to become metabolically activated.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Citostáticos/síntese química , Citostáticos/farmacologia , Nucleosídeos de Purina/química , Animais , Antivirais/química , Linhagem Celular Tumoral , Células Cultivadas , Citostáticos/química , Vírus de DNA/efeitos dos fármacos , Cães , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Herpesvirus Humano 1/enzimologia , Herpesvirus Humano 3/enzimologia , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Fosforilação , Nucleosídeos de Purina/farmacologia , Vírus de RNA/efeitos dos fármacos , Relação Estrutura-Atividade , Timidina/metabolismo , Timidina Quinase/antagonistas & inibidores , Triazóis/química
7.
Biomed Pharmacother ; 63(8): 577-85, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19010640

RESUMO

Dupuytren's disease (DD) is a fibroproliferative disorder, the cure for which is still limited to surgical excision of the affected fascia, often leading to high recurrence rates. Due to this fact, non-surgical treatments are being investigated, among them those targeting molecular processes of proliferation and differentiation in Dupuytren's cell cultures. Drugs with antiproliferative action may be valuable in DD treatment. Through characterization of changes on DD-specific cells, we, therefore, decided to test the therapeutic potential of new cytostatic drugs for DD treatment and/or for reduction of post-operative recurrence rates. The N-sulfonylpyrimidine derivative, amidino-substituted benzimidazo[1,2-a]quinoline, and amidino dihydrothienothienyl[2,3-c]quinolone hydrochloride, known to affect proliferation processes, were tested for their antiproliferative activity on primary fibroblasts/myofibroblasts cell cultures derived from the palmar fascia of patients with DD. Only amidino dihydrothienothienyl[2,3-c]quinolone hydrochloride acted in a highly specific manner on cells derived from diseased fascia of DD patients and exhibited a low cytotoxic effect. This result might be a consequence of its specific activity on cytoskeleton changes occurring in differentiating cells. A similar short-term differential antiproliferative effect was observed by the N-sulfonylpyrimidine derivative that was, however, completely lost after 6- and 14-day treatments. The amidino-substituted benzimidazo[1,2-a]quinoline exerted a strong non-specific, dose-related antiproliferative activity on cell types.


Assuntos
Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Contratura de Dupuytren/tratamento farmacológico , Fáscia/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Pró-Fármacos/farmacologia , Estudos de Casos e Controles , Ciclo Celular/efeitos dos fármacos , Transdiferenciação Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Desenho de Fármacos , Contratura de Dupuytren/patologia , Contratura de Dupuytren/cirurgia , Fáscia/patologia , Fasciotomia , Fibroblastos/patologia , Humanos , Concentração Inibidora 50 , Masculino , Pessoa de Meia-Idade , Estrutura Molecular , Pró-Fármacos/química , Pró-Fármacos/toxicidade , Pirimidinas/farmacologia , Quinolinas/farmacologia , Quinolonas/farmacologia , Recidiva , Relação Estrutura-Atividade , Fatores de Tempo
8.
Bioorg Med Chem ; 15(2): 749-58, 2007 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17092728

RESUMO

The novel C-5 substituted uracil derivatives of l-ascorbic acid were synthesized by coupling of 5-iodouracil-4,5-didehydro-5,6-dideoxy-l-ascorbic acid with unsaturated stannanes under Stille reaction conditions. The new compounds were evaluated for their antitumoral and antiviral activities. Among all compounds evaluated the 5-propynyl substituted uracil derivative of l-ascorbic acid (7) exhibited the most pronounced cytostatic activities against all examined tumor cell lines (IC(50): 0.2-0.78 microM). However, this compound was also cytotoxic to human normal fibroblasts WI 38. The 5-(phenylethynyl)uracil-2,3-di-O-benzylated l-ascorbic acid derivative (4) exhibited an albeit slight (IC(50): 55-108 microM), but selective inhibitory effect toward all tumor cell lines except for cervical carcinoma (HeLa), pancreatic carcinoma (MiaPaCa-2), laryngeal carcinoma (Hep-2), and colon carcinoma (SW 620), and no cytotoxicity to normal human fibroblast (WI 38). Compound 7 showed some, not highly specific, inhibitory potential against vesicular stomatitis virus, Coxsackie B4 virus, and Sindbis viruses (EC(50): 1.6 microM).


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antivirais/síntese química , Antivirais/farmacologia , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/síntese química , Uracila/química , Animais , Ácido Ascórbico/farmacologia , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Fibroblastos/efeitos dos fármacos , Humanos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Pirimidinas/química , Relação Estrutura-Atividade , Vírus/efeitos dos fármacos
9.
Front Biosci ; 11: 1722-32, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16368551

RESUMO

Clinoptilolite is a nontoxic natural zeolite with properties of an ion-exchanger and adsorbent. Earlier studies showed that clinoptilolite could be an adjuvant in cancer therapy. The aim of this study was to define effects of clinoptilolite in cell media on cell viability and activity of key proteins regulating cell survival, cell division and stress response. The number of viable cells, DNA synthesis and activity of EGF-R, PKB/Akt and NF?B was reduced, while apoptosis was increased in cells that were cultured in medium supplemneted with clinoptilolite. These results might be due to adsorbtion of some serum components such as EGF to clinoptilolite. In treated medium without serum the predominant role of clinoptilolite is that of cation exchange, likely affecting calcium levels and calcium-dependent signalling pathways. These results are in line with other data that confirm enhanced apoptosis in cells incubated in treated medium. Together, data presented here demonstrate that clinoptilolite affects cellular microenvironment through mechanisms that are dependent on adsorptive and ion-exchange characteristics of this material.


Assuntos
Neoplasias/metabolismo , Zeolitas/farmacologia , Animais , Apoptose , Western Blotting , Cálcio/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Cromatografia por Troca Iônica/métodos , Meios de Cultura/farmacologia , DNA/metabolismo , Receptores ErbB/metabolismo , Humanos , Imunoprecipitação , Técnicas In Vitro , Íons , MAP Quinase Quinase 4/metabolismo , Camundongos , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia , Timidina/química , Fatores de Tempo
11.
Bioorg Med Chem ; 13(1): 131-9, 2005 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-15582458

RESUMO

The syntheses of the novel C-5 substituted pyrimidine derivatives of l-ascorbic acid containing free hydroxy groups at C-2' (6-10) or C-2' and C-3' (11-15) positions of the lactone ring are described. Debenzylation of the 6-chloro- and 6-(N-pyrrolyl)purine derivatives of 2,3-O,O-dibenzyl-l-ascorbic acid (16 and 17) gave the new compounds containing hydroxy groups at C-2' (18) and C-2' and C-3' (19 and 20). Z- and E-configuration of the C4'C5' double bond and position of the lactone ring of the compounds 6-9 were deduced from their one- and two-dimensional (1)H and (13)C NMR spectra and connectivities in NOESY and HMBC spectra. Compounds 15 and 18 showed the best inhibitory activities of all evaluated compounds in the series. The compound 15 containing 5-(trifluoromethyl)uracil showed marked inhibitory activity against all human malignant cell lines (IC(50): 5.6-12.8 microM) except on human T-lymphocytes. Besides, this compound influenced the cell cycle by increasing the cell population in G2/M phase and induced apoptosis in SW 620 and MiaPaCa-2 cells. The compound 18 containing 6-chloropurine ring expressed the most pronounced inhibitory activities against HeLa (IC(50): 6.8 microM) and MiaPaCa-2 cells (IC(50): 6.5 microM). The compound 20 with 6-(N-pyrrolyl)purine moiety showed the best differential inhibitory effect against MCF-7 cells (IC(50): 35.9 microM).


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antivirais/síntese química , Antivirais/farmacologia , Ácido Ascórbico/síntese química , Ácido Ascórbico/farmacologia , Purinas/química , Pirimidinas/química , Antineoplásicos/química , Antivirais/química , Ácido Ascórbico/química , Isótopos de Carbono , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Humanos , Espectroscopia de Ressonância Magnética , Prótons , Espectrofotometria Ultravioleta
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