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1.
Semin Cancer Biol ; 86(Pt 3): 652-665, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34020027

RESUMO

Cancer is one of the leading global causes of death in both men and women. Colorectal cancer (CRC) alone accounts for ∼10 % of total new global cases and poses an over 4% lifetime risk of developing cancer. Recent advancements in the field of biotechnology and microbiology concocted novel microbe-based therapies to treat various cancers, including CRC. Microbes have been explored for human use since centuries, especially for the treatment of various ailments. The utility of microbes in cancer therapeutics is widely explored, and various bacteria, fungi, and viruses are currently in use for the development of cancer therapeutics. The human gut hosts about 100 trillion microbes that release their metabolites in active, inactive, or dead conditions. Microbial secondary metabolites, proteins, immunotoxins, and enzymes are used to target cancer cells to induce cell cycle arrest, apoptosis, and death. Various approaches, such as dietary interventions, the use of prebiotics and probiotics, and fecal microbiota transplantation have been used to modulate the gut microbiota in order to prevent or treat CRC pathogenesis. The present review highlights the role of the gut microbiota in CRC precipitation, the potential mechanisms and use of microorganisms as CRC biomarkers, and strategies to modulate microbiota for the prevention and treatment of CRC.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Microbiota , Probióticos , Masculino , Humanos , Feminino , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/terapia , Neoplasias Colorretais/metabolismo , Prebióticos , Probióticos/uso terapêutico
2.
RNA ; 27(1): 66-79, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33023933

RESUMO

Most mammalian cytoplasmic tRNAs contain ribothymidine (T) and pseudouridine (Ψ) at positions 54 and 55, respectively. However, some tRNAs contain Ψ at both positions. Several Ψ54-containing tRNAs function as primers in retroviral DNA synthesis. The Ψ54 of these tRNAs is produced by PUS10, which can also synthesize Ψ55. Two other enzymes, TRUB1 and TRUB2, can also produce Ψ55. By nearest-neighbor analyses of tRNAs treated with recombinant proteins and subcellular extracts of wild-type and specific Ψ55 synthase knockdown cells, we determined that while TRUB1, PUS10, and TRUB2 all have tRNA Ψ55 synthase activities, they have different tRNA structural requirements. Moreover, these activities are primarily present in the nucleus, cytoplasm, and mitochondria, respectively, suggesting a compartmentalization of Ψ55 synthase activity. TRUB1 produces the Ψ55 of most elongator tRNAs, but cytoplasmic PUS10 produces both Ψs of the tRNAs with Ψ54Ψ55. The nuclear isoform of PUS10 is catalytically inactive and specifically binds the unmodified U54U55 versions of Ψ54Ψ55-containing tRNAs, as well as the A54U55-containing tRNAiMet This binding inhibits TRUB1-mediated U55 to Ψ55 conversion in the nucleus. Consequently, the U54U55 of Ψ54Ψ55-containing tRNAs are modified by the cytoplasmic PUS10. Nuclear PUS10 does not bind the U55 versions of T54Ψ55- and A54Ψ55-containing elongator tRNAs. Therefore, TRUB1 is able to produce Ψ55 in these tRNAs. In summary, the tRNA Ψ55 synthase activities of TRUB1 and PUS10 are not redundant but rather are compartmentalized and act on different sets of tRNAs. The significance of this compartmentalization needs further study.


Assuntos
Núcleo Celular/genética , Citoplasma/genética , Hidroliases/genética , Mitocôndrias/genética , Pseudouridina/metabolismo , RNA de Transferência de Alanina/genética , RNA de Transferência de Metionina/genética , RNA de Transferência de Triptofano/genética , Animais , Sítios de Ligação , Compartimento Celular , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Expressão Gênica , Células HEK293 , Humanos , Hidroliases/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Mitocôndrias/metabolismo , Células PC-3 , Ligação Proteica , RNA de Transferência de Alanina/metabolismo , RNA de Transferência de Metionina/metabolismo , RNA de Transferência de Triptofano/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Células Sf9 , Spodoptera
3.
Exp Eye Res ; 227: 109355, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36572166

RESUMO

Pesticide exposure to eyes is a major source of ocular morbidities in adults and children all over the world. Carbofuran (CF), N-methyl carbamate, pesticide is most widely used as an insecticide, nematicide, and acaricide in agriculture, forestry, and gardening. Contact or ingestion of carbofuran causes high morbidity and mortality in humans and pets. Pesticides are absorbed in the eye faster than other organs of the body and damage ocular tissues very quickly. Carbofuran exposure to eye causes blurred vision, pain, loss of coordination, anti-cholinesterase activities, weakness, sweating, nausea and vomiting, abdominal pain, endocrine, reproductive, and cytotoxic effects in humans depending on amount and duration of exposure. Pesticide exposure to eye injures cornea, conjunctiva, lens, retina, and optic nerve and leads to abnormal ocular movement and vision impairment. Additionally, anticholinesterase pesticides like carbofuran are known to cause salivation, lacrimation, urination, and defecation (SLUD). Carbofuran and its two major metabolites (3-hydroxycarbofuran and 3-ketocarbofuran) are reversible inhibitors of acetylcholinesterase (AChE) which regulates acetylcholine (ACh), a neurohumoral chemical that plays an important role in corneal wound healing. The corneal epithelium contains high levels of ACh whose accumulation by AChE inhibition after CF exposure overstimulates muscarinic ACh receptors (mAChRs) and nicotinic ACh receptors (nAChRs). Hyper stimulation of mAChRs in the eye causes miosis (excessive constriction of the pupil), dacryorrhea (excessive flow of tears), or chromodacryorrhea (red tears). Recent studies reported alteration of autophagy mechanism in human cornea in vitro and ex vivo post carbofuran exposure. This review describes carbofuran toxicity to the eye with special emphasis on corneal morbidities and blindness.


Assuntos
Carbofurano , Inseticidas , Praguicidas , Adulto , Criança , Humanos , Carbofurano/toxicidade , Carbofurano/metabolismo , Acetilcolinesterase/metabolismo , Inseticidas/toxicidade , Inseticidas/metabolismo , Inibidores da Colinesterase , Praguicidas/toxicidade , Receptores Colinérgicos
4.
Molecules ; 28(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36838654

RESUMO

Complexes of curcumin with metals have shown much-improved stability, solubility, antioxidant capability, and efficacy when compared to curcumin. The present research investigates the relative bioavailability, antioxidant, and ability to inhibit inflammatory cytokine production of a curcuminoid metal chelation complex of tetrahydrocurcumin-zinc-curcuminoid termed TurmiZn. In vitro uptake assay using pig intestinal epithelial cells showed that TurmiZn has an ~3-fold increase (p ≤ 0.01) in uptake compared to curcumin and a ~2-fold increase (p ≤ 0.01) over tetrahydrocurcumin (THC). In a chicken model, an oral 1-g dose of TurmiZn showed a ~2.5-fold increase of a specific metabolite peak compared to curcumin (p = 0.004) and a ~3-fold increase compared to THC (p = 0.001). Oral doses (5 g/Kg) of TurmiZn in rats also showed the presence of curcumin and THC metabolites in plasma, indicating bioavailability across cell membranes in animals. Determination of the antioxidant activity by a 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging assay indicated that TurmiZn was about 13x better (p ≤ 0.0001) than curcumin and about 4X better (p ≤ 0.0001) than THC, in reducing free radicals. In vitro experiments further showed significant (p ≤ 0.01) reductions of lipopolysaccharide (LPS)-induced proinflammatory cytokines such as interleukin (IL) IL-6, IL-8, IL-15, IL-18, and tumor necrosis factor (TNF)-alpha, while showing a significant (p ≤ 0.01) increase of granulocyte-macrophage colony-stimulating factor (GM-CSF) in dog kidney cells. In vivo cytokine modulations were also observed when TurmiZn was fed for 6 weeks to newborn chickens. TurmiZn reduced IL-1 and IL-6, but significantly reduced (p ≤ 0.01) IL-10 levels while there was a concurrent significant (p = 0.02) increase in interferon gamma compared to controls. Overall, these results indicate that TurmiZn has better bioavailability and antioxidant capability than curcumin or THC and has the ability to significantly modulate cytokine levels. Thus, TurmiZn could be an excellent candidate for a novel ingredient that can be incorporated into food and supplements to help overall health during the aging process.


Assuntos
Curcumina , Citocinas , Animais , Ratos , Suínos , Cães , Antioxidantes/farmacologia , Curcumina/farmacologia , Interleucina-6 , Diarileptanoides , Disponibilidade Biológica , Zinco , Galinhas , Fator de Necrose Tumoral alfa
5.
RNA ; 26(4): 396-418, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31919243

RESUMO

Archaea and eukaryotes, in addition to protein-only enzymes, also possess ribonucleoproteins containing an H/ACA guide RNA plus four proteins that produce pseudouridine (Ψ). Although typical conditions for these RNA-guided reactions are known, certain variant conditions allow pseudouridylation. We used mutants of the two stem-loops of the Haloferax volcanii sR-h45 RNA that guides three pseudouridylations in 23S rRNA and their target RNAs to characterize modifications under various atypical conditions. The 5' stem-loop produces Ψ2605 and the 3' stem-loop produces Ψ1940 and Ψ1942. The latter two modifications require unpaired "UVUN" (V = A, C, or G) in the target and ACA box in the guide. Ψ1942 modification requires the presence of U1940 (or Ψ1940). Ψ1940 is not produced in the Ψ1942-containing substrate, suggesting a sequential modification of the two residues. The ACA box of a single stem-loop guide is not required when typically unpaired "UN" is up to 17 bases from its position in the guide, but is needed when the distance increases to 19 bases or the N is paired. However, ANA of the H box of the double stem-loop guide is needed even for the 5' typical pseudouridylation. The most 5' unpaired U in a string of U's is converted to Ψ, and in the absence of an unpaired U, a paired U can also be modified. Certain mutants of the Cbf5 protein affect pseudouridylation by the two stem-loops of sR-h45 differently. This study will help elucidate the conditions for production of nonconstitutive Ψ's, determine functions for orphan H/ACA RNAs and in target designing.


Assuntos
Pseudouridina/metabolismo , Processamento Pós-Transcricional do RNA , RNA Arqueal/genética , RNA Guia de Cinetoplastídeos/genética , Proteínas Arqueais/metabolismo , Haloferax volcanii/genética , Motivos de Nucleotídeos , Pseudouridina/química , RNA Arqueal/química , RNA Arqueal/metabolismo , RNA Guia de Cinetoplastídeos/química , RNA Guia de Cinetoplastídeos/metabolismo
6.
Adv Exp Med Biol ; 1370: 99-111, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35882785

RESUMO

Psoriasis is a chronic skin auto-inflammatory and systemic disorder. Novel treatments are needed to solve a plethora of cases refractory to current treatment regimens. N-bromotaurine (TauNH-Br), a natural taurine oxidizing derivative produced by inflammatory cells, has anti-inflammatory, antiproliferative, and antimicrobial properties. This evidence prompted us to use TauNH-Br as a local agent for treatment of therapy-refractory psoriasis. Two pustular-plaque psoriasis cases, unresponsive to systemic and local treatments, one with localized lesions and one with generalized lesions, were selected. Both applications primarily indicated a sufficient curative activity of 1% TauNH-Br in psoriasis lesions. Moreover, TauNH-Br co-administration with taurine and a novel olive oil formulation cut in half the time needed for TauNH-Br alone to cause the same regression of equivalent psoriasis plaque lesions in the same patient. Importantly, all adverse effects of TauNH-Br (erythema, itching, bleeding) could be minimized by the combination therapy. Periods of 2-7 weeks to achieve almost complete regression with this formulation were remarkably short as compared to conventional treatment regimens that both patients had followed previously. Of note, there was no relapse within 3 months of monitoring. Combination formulations containing TauNH-Br and olive oil could become an advantageous topical medication for treatment of psoriasis.


Assuntos
Exantema , Psoríase , Administração Tópica , Humanos , Azeite de Oliva/uso terapêutico , Psoríase/tratamento farmacológico , Taurina/análogos & derivados , Taurina/farmacologia , Taurina/uso terapêutico
7.
RNA ; 25(3): 336-351, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30530625

RESUMO

The nearly conserved U54 of tRNA is mostly converted to a version of ribothymidine (T) in Bacteria and eukaryotes and to a version of pseudouridine (Ψ) in Archaea. Conserved U55 is nearly always modified to Ψ55 in all organisms. Orthologs of TrmA and TruB that produce T54 and Ψ55, respectively, in Bacteria and eukaryotes are absent in Archaea. Pus10 produces both Ψ54 and Ψ55 in Archaea. Pus10 orthologs are found in nearly all sequenced archaeal and most eukaryal genomes, but not in yeast and bacteria. This coincides with the presence of Ψ54 in most archaeal tRNAs and some animal tRNAs, but its absence from yeast and bacteria. Moreover, Ψ54 is found in several tRNAs that function as primers for retroviral DNA synthesis. Previously, no eukaryotic tRNA Ψ54 synthase had been identified. We show here that human Pus10 can produce Ψ54 in select tRNAs, including tRNALys3, the primer for HIV reverse transcriptase. This synthase activity of Pus10 is restricted to the cytoplasm and is distinct from nuclear Pus10, which is known to be involved in apoptosis. The sequence GUUCAm1AAUC (m1A is 1-methyladenosine) at position 53-61 of tRNA along with a stable acceptor stem results in maximum Ψ54 synthase activity. This recognition sequence is unique for a Ψ synthase in that it contains another modification. In addition to Ψ54, SF9 cells-derived recombinant human Pus10 can also generate Ψ55, even in tRNAs that do not contain the Ψ54 synthase recognition sequence. This activity may be redundant with that of TruB.


Assuntos
Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Hidroliases/genética , Hidroliases/metabolismo , Pseudouridina/biossíntese , RNA de Transferência/genética , Animais , Archaea/genética , Archaea/metabolismo , Sequência de Bases , Citoplasma , Ativação Enzimática , Humanos , Mamíferos/genética , Proteólise , Processamento Pós-Transcricional do RNA , RNA Arqueal , Proteínas Recombinantes , Elementos de Resposta , Seleção Genética
8.
J Card Fail ; 27(2): 242-252, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33352205

RESUMO

BACKGROUND: Unlike ß1- and ß2-adrenergic receptors (ARs), ß3-AR stimulation inhibits cardiac contractility and relaxation. In the failing left ventricular (LV) myocardium, ß3-ARs are upregulated, and can be maladaptive in the setting of decompensation by contributing to LV dysfunction. This study examined the effects of intravenous infusions of the ß3-AR antagonist APD418 on cardiovascular function and safety in dogs with systolic heart failure (HF). METHODS AND RESULTS: Three separate studies were performed in 21 dogs with coronary microembolization-induced HF (LV ejection fraction [LVEF] of approximately 35%). Studies 1 and 2 (n = 7 dogs each) were APD418 dose escalation studies (dosing range, 0.35-15.00 mg/kg/h) designed to identify an effective dose of APD418 to be used in study 3. Study 3, the sustained efficacy study, (n = 7 dogs) was a 6-hour constant intravenous infusion of APD418 at a dose of 4.224 mg/kg (0.70 mg/kg/h) measuring key hemodynamic endpoints (e.g., EF, cardiac output, the time velocity integral of the mitral inflow velocity waveform representing early filling to time-velocity integral representing left atrial contraction [Ei/Ai]). Studies 1 and 2 showed a dose-dependent increase of LVEF and Ei/Ai, the latter being an index of LV diastolic function. In study 3, infusion of APD418 over 6 hours increased LVEF from 31 ± 1% to 38 ± 1% (P < .05) and increased Ei/Ai from 3.4 ± 0.4 to 4.9 ± 0.5 (P < .05). Vehicle had no effect on the LVEF or Ei/Ai. In study 3, APD418 had no significant effects on the HR or the systemic blood pressure. CONCLUSIONS: Intravenous infusions of APD418 in dogs with systolic HF elicit significant positive inotropic and lusitropic effects. These findings support the development of APD418 for the in-hospital treatment of patients with an acute exacerbation of chronic HF.


Assuntos
Insuficiência Cardíaca Sistólica , Insuficiência Cardíaca , Antagonistas Adrenérgicos beta/uso terapêutico , Animais , Cães , Átrios do Coração , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca Sistólica/tratamento farmacológico , Humanos , Infusões Intravenosas , Função Ventricular Esquerda
9.
Int J Mol Sci ; 22(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201250

RESUMO

Breast cancer (BC) is a leading cause of cancer deaths in women in less developed countries and the second leading cause of cancer death in women in the U.S. In this study, we report the inhibition of E2-mediated mammary tumorigenesis by Cuminum cyminum (cumin) administered via the diet as cumin powder, as well as dried ethanolic extract. Groups of female ACI rats were given either an AIN-93M diet or a diet supplemented with cumin powder (5% and 7.5%, w/w) or dried ethanolic cumin extract (1%, w/w), and then challenged with subcutaneous E2 silastic implants (1.2 cm; 9 mg). The first appearance of a palpable mammary tumor was significantly delayed by both the cumin powder and extract. At the end of the study, the tumor incidence was 96% in the control group, whereas only 55% and 45% animals had palpable tumors in the cumin powder and extract groups, respectively. Significant reductions in tumor volume (660 ± 122 vs. 138 ± 49 and 75 ± 46 mm3) and tumor multiplicity (4.21 ± 0.43 vs. 1.16 ± 0.26 and 0.9 ± 0.29 tumors/animal) were also observed by the cumin powder and cumin extract groups, respectively. The cumin powder diet intervention dose- and time-dependently offset E2-related pituitary growth, and reduced the levels of circulating prolactin and the levels of PCNA in the mammary tissues. Mechanistically, the cumin powder diet resulted in a significant reversal of E2-associated modulation in ERα, CYP1A1 and CYP1B1. Further, the cumin powder diet reversed the expression levels of miRNAs (miR-182, miR-375, miR-127 and miR-206) that were highly modulated by E2 treatment. We analyzed the composition of the extract by GC/MS and established cymene and cuminaldehyde as major components, and further detected no signs of gross or systemic toxicity. Thus, cumin bioactives can significantly delay and prevent E2-mediated mammary tumorigenesis in a safe and effective manner, and warrant continued efforts to develop these clinically translatable spice bioactives as chemopreventives and therapeutics against BC.


Assuntos
Cuminum/química , Estradiol/toxicidade , Estrogênios/toxicidade , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Mamárias Experimentais/prevenção & controle , Extratos Vegetais/farmacologia , Animais , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/metabolismo , Feminino , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , MicroRNAs/genética , Ratos , Ratos Endogâmicos ACI
10.
J Card Fail ; 26(11): 987-997, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32841710

RESUMO

BACKGROUND: Sacubitril/valsartan (Sac/Val), a combined angiotensin-II receptor blocker (Val) and neprilysin inhibitor (Sac) in a 1:1 molar ratio, was shown to decrease the risk of cardiovascular death or heart failure (HF) hospitalization in patients with HF and reduced left ventricular (LV) ejection fraction. This study examined the effects of Sac/Val on LV structure, function, and bioenergetics, and on biomarkers of kidney injury and kidney function in dogs with experimental cardiorenal syndrome. METHODS AND RESULTS: Fourteen dogs with cardiorenal syndrome (coronary microembolization-induced HF and renal dysfunction) were randomized to 3 months Sac/Val therapy (100 mg once daily, n = 7) or no therapy (control, n = 7). LV ejection fraction and troponin-I, as well as biomarkers of kidney injury/function including serum creatinine and urinary kidney injury molecule-1 were measured before and at end of therapy and the change (treatment effect change) calculated. Mitochondrial function measures, including the maximum rate of adenosine triphosphate synthesis, were measured in isolated cardiomyocytes at end of therapy. In Sac/Val dogs, the change in ejection fraction increased compared with controls, 6.9 ± 1.4 vs 0.7 ± 0.6%, P < .002, whereas change in troponin I decreased, -0.16 ± 0.03 vs -0.03 ± 0.02 ng/mL, P < .001. Urinary change in kidney injury molecule 1 decreased in Sac/Val-treated dogs compared with controls, -17.2 ± 7.9 vs 7.7 ± 3.0 mg/mL, P < .007, whereas the change in serum creatinine was not significantly different. Treatment with Sac/Val increased adenosine triphosphate synthesis compared with controls, 3240 ± 121 vs 986 ± 84 RLU/µg protein, P < .05. CONCLUSIONS: In dogs with cardiorenal syndrome, Sac/Val improves LV systolic function, improves mitochondrial function and decreases biomarkers of heart and kidney injury. The results offer mechanistic insights into the benefits of Sac/Val in HF with compromised renal function.


Assuntos
Síndrome Cardiorrenal , Insuficiência Cardíaca , Animais , Cães , Angiotensinas , Síndrome Cardiorrenal/tratamento farmacológico , Neprilisina , Volume Sistólico
11.
Cardiovasc Drugs Ther ; 34(2): 153-164, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32146638

RESUMO

PURPOSE: Vepoloxamer (VEPO), a rheologic agent, repairs damaged cell membranes, thus inhibiting unregulated Ca2+ entry into cardiomyocytes. This study examined the effects of i.v. infusion of VEPO on LV function in dogs with coronary microembolization-induced heart failure (HF) (LV ejection fraction, EF ~ 30%). METHODS: Thirty-five HF dogs were studied. Study 1: 21 of 35 dogs were randomized to 2-h infusion of VEPO at dose of 450 mg/kg (n = 7) or VEPO at 225 mg/kg (n = 7) or normal saline (control, n = 7). Hemodynamics were measured at 2 h, 24 h, 1 week, and 2 weeks after infusion. Study 2: 14 HF dogs were randomized to 2-h infusions of VEPO (450 mg/kg, n = 7) or normal saline (control, n = 7). Each dog received 2 infusions of VEPO or saline (pulsed therapy) 3 weeks apart and hemodynamics measured at 24 h, and 1, 2, and 3 weeks after each infusion. In both studies, the change between pre-infusion measures and measures at other time points (treatment effect, Δ) was calculated. RESULTS: Study 1: compared to pre-infusion, high dose VEPO increased LVEF by 11 ± 2% at 2 h, 8 ± 2% at 24 h (p < 0.05), 8 ± 2% at 1 week (p < 0.05), and 4 ± 2% at 2 weeks. LV EF also increased with low-dose VEPO but not with saline. Study 2: VEPO but not saline significantly increased LVEF by 6.0 ± 0.7% at 2 h (p < 0.05); 7.0 ± 0.7%% at 1 week (p < 0.05); 1.0 ± 0.6% at 3 weeks; 6.0 ± 1.3% at 4 weeks (p < 0.05); and 5.9 ± 1.3% at 6 weeks (p < 0.05). CONCLUSIONS: Intravenous VEPO improves LV function for at least 1 week after infusion. The benefits can be extended with pulsed VEPO therapy. The results support development of VEPO for treating patients with acute on chronic HF.


Assuntos
Fármacos Cardiovasculares/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Poloxâmero/administração & dosagem , Volume Sistólico/efeitos dos fármacos , Disfunção Ventricular Esquerda/tratamento farmacológico , Função Ventricular Esquerda/efeitos dos fármacos , Animais , Sinalização do Cálcio/efeitos dos fármacos , Modelos Animais de Doenças , Cães , Relação Dose-Resposta a Droga , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Infusões Intravenosas , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia
12.
Molecules ; 24(23)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775281

RESUMO

Gut health is the starting place for maintaining the overall health of an animal. Strategies to maintain gut health are, thus, an important part in achieving the goal of improving animal health. A new strategy to do this involves two molecules: the iron transport protein ovotransferrin (IT) and α-tocopheryl polyethylene glycol succinate (TPGS), which result in the novel formulation of ITPGS. These molecules help reduce gut pathogens, while enhancing the absorption and bioavailability of therapeutic drugs, phytomedicines, and nanomedicines. This, in turn, helps to maintain normal health in animals. Maintaining the gastrointestinal tract (GIT) in its normal condition is key for successful absorption and efficacy of any nutrient. A compromised GIT, due to an imbalance (dysbiosis) in the GIT microbiome, can lead to an impaired GI barrier system with impaired absorption and overall health of the animal. The molecules in ITPGS may address the issue of poor absorption by keeping the GI system healthy by maintaining the normal microbiome and improving the absorption of nutrients through multiple mechanisms involving antioxidative, anti-inflammatory, immunomodulatory, and antimicrobial activities. The ITPGS technology can allow the dose of active pharmaceutical or herbal medicine to be significantly reduced in order to attain equal or better efficacy. With complimentary actions between IT and TPGS, ITPGS presents a novel approach to increase the bioavailability of drugs, phytoconstituents, nutrients, and nanomedicines by enhanced transport to the tissues at the site of action, while reducing gut pathogen load. The ITPGS approach appears to be a novel strategy for maintaining the health of animals by manipulation of microbiota.


Assuntos
Conalbumina/farmacologia , Trato Gastrointestinal/efeitos dos fármacos , Gastropatias/tratamento farmacológico , Vitamina E/farmacologia , Animais , Disponibilidade Biológica , Conalbumina/química , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Trato Gastrointestinal/microbiologia , Ferro/metabolismo , Gastropatias/veterinária , Vitamina E/química
13.
J Mol Evol ; 86(1): 77-89, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29349599

RESUMO

In archaea, pseudouridine (Ψ) synthase Pus10 modifies uridine (U) to Ψ at positions 54 and 55 of tRNA. In contrast, Pus10 is not found in bacteria, where modifications at those two positions are carried out by TrmA (U54 to m5U54) and TruB (U55 to Ψ55). Many eukaryotes have an apparent redundancy; their genomes contain orthologs of archaeal Pus10 and bacterial TrmA and TruB. Although eukaryal Pus10 genes share a conserved catalytic domain with archaeal Pus10 genes, their biological roles are not clear for the two reasons. First, experimental evidence suggests that human Pus10 participates in apoptosis induced by the tumor necrosis factor-related apoptosis-inducing ligand. Whether the function of human Pus10 is in place or in addition to of Ψ synthesis in tRNA is unknown. Second, Pus10 is found in earlier evolutionary branches of fungi (such as chytrid Batrachochytrium) but is absent in all dikaryon fungi surveyed (Ascomycetes and Basidiomycetes). We did a comprehensive analysis of sequenced genomes and found that orthologs of Pus10, TrmA, and TruB were present in all the animals, plants, and protozoa surveyed. This indicates that the common eukaryotic ancestor possesses all the three genes. Next, we examined 116 archaeal and eukaryotic Pus10 protein sequences to find that Pus10 existed as a single copy gene in all the surveyed genomes despite ancestral whole genome duplications had occurred. This indicates a possible deleterious gene dosage effect. Our results suggest that functional redundancy result in gene loss or neofunctionalization in different evolutionary lineages.


Assuntos
Hidroliases/genética , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Sequência de Aminoácidos/genética , Animais , Archaea/genética , Bactérias/genética , Sequência de Bases/genética , Evolução Biológica , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Eucariotos/genética , Evolução Molecular , Humanos , Hidroliases/metabolismo , Filogenia , Pseudogenes/genética , RNA de Transferência/genética , RNA de Transferência/metabolismo , tRNA Metiltransferases
14.
Anal Chem ; 90(18): 10974-10981, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30106271

RESUMO

The present work describes a new photoinduced electron transfer (PET) based molecular probe in which naphthalimide (NPI) and anthracene (AN) chromophores are linked through a molecular bridge of piperazine and triazole units by the Click reaction. A typical meaningful structural variation has made the present probe highly selective for Cr3+ ion (limit of detection (LOD), 5.567 × 10-8 M) that displayed enhanced, " turn-On" emission (due to the PET- Off photophysical mechanism) and naked-eye sensitive bright green color fluorescence in the environment of interfering and competitive ions, in Tris-HCl buffer. The minimum energy structure obtained through theoretical calculations (density functional theory (DFT) and time-dependent (TD)-DFT) revealed a "tub" shape structure for probe 10. Upon complexation, the conformation of piperazine fragment changes from chair to boat in which the triazole and piperazine units create a cavity to tether Cr3+. Moreover, the probe showed excellent biocompatibility and cell permeability to sense Cr3+ sensitively in live cells and, thus, holds great promise for application in biological and environmental sciences. Additionally, the sensitive " Off-On-Off" sensing behavior of probe 10 providing two chemical inputs (Cr3+ and PO43-) helps to construct an INHIBIT logic gate. Also the probe has been utilized as printing material to decode secret information through the Cr3+ ion containing "marker ink" under UV light.


Assuntos
Cromo/análise , Corantes Fluorescentes/química , Imagem Óptica/métodos , Fosfatos/análise , Sobrevivência Celular , Transporte de Elétrons , Fluorescência , Células HeLa , Humanos , Íons/análise , Modelos Moleculares , Espectrometria de Fluorescência/métodos
15.
RNA ; 22(10): 1604-19, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27539785

RESUMO

In Eukarya and Archaea, in addition to protein-only pseudouridine (Ψ) synthases, complexes containing one guide RNA and four proteins can also produce Ψ. Cbf5 protein is the Ψ synthase in the complex. Previously, we showed that Ψ's at positions 1940, 1942, and 2605 of Haloferax volcanii 23S rRNA are absent in a cbf5-deleted strain, and a plasmid-borne copy of cbf5 can rescue the synthesis of these Ψ's. Based on published reports of the structure of archaeal Cbf5 complexed with other proteins and RNAs, we identified several potential residues and structures in H. volcanii Cbf5, which were expected to play important roles in pseudouridylation. We mutated these structures and determined their effects on Ψ production at the three rRNA positions under in vivo conditions. Mutations of several residues in the catalytic domain and certain residues in the thumb loop either abolished Ψ's or produced partial modification; the latter indicates a slower rate of Ψ formation. The universal catalytic aspartate of Ψ synthases could be replaced by glutamate in Cbf5. A conserved histidine, which is common to Cbf5 and TruB is not needed, but another conserved histidine of Cbf5 is required for the in vivo RNA-guided Ψ formation. We also identified a previously unreported novelty in the pseudouridylation activity of Cbf5 where a single stem-loop of a guide H/ACA RNA is used to produce two closely placed Ψ's and mutations of certain residues of Cbf5 abolished one of these two Ψ's. In summary, this first in vivo study identifies several structures of an archaeal Cbf5 protein that are important for its RNA-guided pseudouridylation activity.


Assuntos
Proteínas Arqueais/química , Haloferax volcanii/enzimologia , Transferases Intramoleculares/química , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Domínio Catalítico , Sequência Conservada , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Mutação , RNA Ribossômico/metabolismo , Relação Estrutura-Atividade
16.
Cardiovasc Drugs Ther ; 32(4): 319-328, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29951944

RESUMO

PURPOSE: Abnormalities of MITO dynamics occur in HF and have been implicated in disease progression. This study describes the broad range abnormalities of mitochondrial (MITO) dynamics in Heart Failure with reduced ejection fraction (HF) and evaluates the effects of long-term therapy with elamipretide (ELAM), a MITO-targeting peptide, on these abnormalities. METHODS: Studies were performed in left ventricular tissue from dogs and humans with HF, and were compared with tissue from healthy dogs and healthy donor human hearts. Dogs with HF were randomized to 3 months therapy with ELAM or vehicle. The following were evaluated in dog and human hearts: (1) regulators of MITO biogenesis, including endothelial nitric oxide synthase (eNOS), cyclic guanosine monophosphate (cGMP), and peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α, a transcription factor that drives MITO biogenesis); (2) regulators of MITO fission and fusion, including fission-1, dynamin-related protein-1, mitofusion-2, dominant optic atrophy-1, and mitofilin; and (3) determinants of cardiolipin (CL) synthesis and remodeling, including CL synthase-1, tafazzin-1, and acyl-CoA:lysocardiolipin acyltransferase-1. RESULTS: The study showed decreased levels of eNOS, cGMP, and PGC-1α in HF (dog and human). Increased levels of fission-associated proteins, decreased levels of fusion-associated proteins, decreased mitofilin, and abnormalities of CL synthesis and remodeling were also observed. In all instances, these maladaptations were normalized following long-term therapy with ELAM. CONCLUSIONS: Critical abnormalities of MITO dynamics occur in HF and are normalized following long-term therapy with ELAM. The findings provide support for the continued development of ELAM for the treatment of HF.


Assuntos
Fármacos Cardiovasculares/farmacologia , Insuficiência Cardíaca/tratamento farmacológico , Mitocôndrias Cardíacas/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Oligopeptídeos/farmacologia , Animais , Modelos Animais de Doenças , Cães , Metabolismo Energético/efeitos dos fármacos , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fatores de Tempo
17.
Nanomedicine ; 14(5): 1629-1641, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29684527

RESUMO

The present report deals with conjugation of dual drug; docetaxel (DTX) and gemcitabine (GEM) with linker poly-ethylene-glycol (PEG) to develop amphiphilic molecule having self-assembled property. The synthesized conjugate (DTX-PEG-GEM) demonstrated critical micelle concentration (CMC) in the range of 5-10 µg/ml which self-assembled to form NPs with size 124.2 ±â€¯5.7. Remarkably higher coumarin-6 (C-6) fluorescence signals observed in case of C-6 loaded NPs, suggested enhanced cellular uptake via clathrin mediated endocytosis. Developed NPs demonstrated 4.8-fold higher AUC(0-∞) value of GEM in comparison with Gemzar®. Tumor growth inhibition study demonstrated significant reduction in tumor volume and higher survival rate with NPs. Moreover, NPs demonstrated significantly lower hepato- and nephro-toxicity, evident from both histopathological sections and biochemical markers level estimation, and hemolytic toxicity. Data in hand suggest enhanced therapeutic efficacy and reduced toxicity of developed NPs over conventional drugs, resulting in efficient combinatorial chemotherapeutic-regimen and patient compliance, which is still an unmet task.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Nanopartículas/administração & dosagem , Polietilenoglicóis/química , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/química , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Docetaxel/administração & dosagem , Feminino , Humanos , Micelas , Nanopartículas/química , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
18.
Drug Dev Ind Pharm ; 44(7): 1120-1129, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29430979

RESUMO

Nanotechnology based biomedical approaches and surface modification techniques made it easier for targeting specific site and improving the treatment efficacy. The present study reports on targeted polymeric nanoparticles conjugated with antibody as a site-specific carrier system for effective treatment of type 1 diabetes. Sitagliptin (SP)-loaded Poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NP) were prepared by nanoprecipitation cum solvent evaporation method and were characterized in terms of morphology, size, surface charge, and entrapment efficiency. Optimized batch demonstrated a particle size of 105.24 nm, with significant entrapment efficacy. In vitro release studies exhibited a controlled release pattern of 67.76 ± 1.30% in 24 h, and a maximum of 96.59 ± 1.26% at the end of 48 h. Thiol groups were introduced on the surface of SP-NPs whose concentration on SP-NPs was 27 ± 2.6 mmol/mol PLGA-NPs, anti-CD4 antibody clone Q4120 was conjugated to the thiolated SP-NPs via a sulfo-MBS cross-linker, ∼70% conjugation was observed. The in vitro cytotoxicity studies performed on RIN-5 F cells for mAb-SP-NPs presented an IC50 of 76 µg/mL, and the insulin release assay had revealed an increased release at 5.15 ± 0.16 IU/mL. The results indicate that mAb-SP-NPs allowed a controlled release of SP and thereby produced insulin levels comparable with control. Therefore, mAb-SP-NPs system appears to be effective in the treatment of auto immune diabetes, subject to further analysis.


Assuntos
Anticorpos/química , Antígenos CD4/química , Diabetes Mellitus Tipo 1/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/química , Inibidores da Dipeptidil Peptidase IV/farmacologia , Nanopartículas/química , Polímeros/química , Animais , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Dipeptidil Peptidase 4/metabolismo , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Ácido Láctico/química , Tamanho da Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos
19.
Pharm Res ; 34(11): 2295-2311, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28795274

RESUMO

PURPOSE: The present study reports a novel conjugate of gemcitabine (GEM) with bovine serum albumin (BSA) and thereof nanoparticles (GEM-BSA NPs) to potentiate the therapeutic efficacy by altering physicochemical properties, improving cellular uptake and stability of GEM. METHODS: The synthesized GEM-BSA conjugate was extensively characterized by NMR, FTIR, MALDI-TOF and elemental analysis. Conjugation mediated changes in structural conformation and physicochemical properties were analysed by fluorescence, Raman and CD spectroscopy, DSC and contact angle analysis. Further, BSA nanoparticles were developed from BSA-GEM conjugate and extensively evaluated against in-vitro pancreatic cancer cell lines to explore cellular uptake pathways and therapeutic efficacy. RESULTS: Various characterization techniques confirmed covalent conjugation of GEM with BSA. GEM-BSA conjugate was then transformed into NPs via high pressure homogenization technique with particle size 147.2 ± 7.3, PDI 0.16 ± 0.06 and ZP -19.2 ± 1.4. The morphological analysis by SEM and AFM revealed the formation of smooth surface spherical nanoparticles. Cellular uptake studies in MIA PaCa-2 (GEM sensitive) and PANC-1 (GEM resistant) pancreatic cell lines confirmed energy dependent clathrin internalization/endocytosis as a primary mechanism of NPs uptake. In-vitro cytotoxicity studies confirmed the hNTs independent transport of GEM in MIA PaCa-2 and PANC-1 cells. Moreover, DNA damage and annexin-V assay revealed significantly higher apoptosis level in case of cells treated with GEM-BSA NPs as compared to free GEM. CONCLUSIONS: GEM-BSA NPs were found to potentiate the therapeutic efficacy by altering physicochemical properties, improving cellular uptake and stability of GEM and thus demonstrated promising therapeutic potential over free drug. Graphical Abstract ᅟ.


Assuntos
Antineoplásicos/química , Desoxicitidina/análogos & derivados , Nanopartículas/química , Neoplasias Pancreáticas/tratamento farmacológico , Soroalbumina Bovina/química , Animais , Antineoplásicos/farmacologia , Apoptose , Bovinos , Linhagem Celular Tumoral , Sobrevivência Celular , Desoxicitidina/química , Desoxicitidina/farmacologia , Liberação Controlada de Fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Tamanho da Partícula , Propriedades de Superfície , Gencitabina
20.
Exp Mol Pathol ; 103(3): 320-329, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29157955

RESUMO

Cervical cancer is caused by human papillomavirus (HPV). The disease develops over many years through a series of precancerous lesions. Cervical cancer can be prevented by HPV-vaccination, screening and treatment of precancer before development of cervical cancer. The treatment of high-grade cervical dysplasia (CIN 2+) has traditionally been by cervical conization. Surgical procedures are associated with increased risk of undesirable side effects including bleeding, infection, scarring (stenosis), infertility and complications in later pregnancies. An inexpensive, non-invasive method of delivering therapeutics locally will be favorable to treat precancerous cervical lesions without damaging healthy tissue. The feasibility and safety of a sustained, continuous drug-releasing cervical polymeric implant for use in clinical trials was studied using a large animal model. The goat (Capra hircus), non-pregnant adult female Boer goats, was chosen due to similarities in cervical dimensions to the human. Estrus was induced with progesterone CIDR® vaginal implants for 14days followed by the administration of chorionic gonadotropins 48h prior to removal of the progesterone implants to relax the cervix to allow for the placement of the cervical implant. Cervical implants, containing 2% and 4% withaferin A (WFA), with 8 coats of blank polymer, provided sustained release for a long duration and were used for the animal study. The 'mushroom'-shaped cervical polymeric implant, originally designed for women required redesigning to be accommodated within the goat cervix. The cervical implants were well tolerated by the animals with no obvious evidence of discomfort, systemic or local inflammation or toxicity. In addition, we developed a new method to analyze tissue WFA levels by solvent extractions and LS/MS-MS. WFA was found to be localized to the target and adjacent tissues with 12-16ng WFA/g tissue, with essentially no detectable WFA in distant tissues. This study suggests that the goat is a good large animal model for the future development and evaluation of therapeutic efficacy of continuous local drug delivery by cervical polymeric implants to treat precancerous cervical lesions.


Assuntos
Sistemas de Liberação de Medicamentos , Infecções por Papillomavirus/tratamento farmacológico , Displasia do Colo do Útero/tratamento farmacológico , Vitanolídeos/administração & dosagem , Animais , Modelos Animais de Doenças , Feminino , Cabras , Humanos , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Gravidez , Displasia do Colo do Útero/complicações , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
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