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1.
Proc Natl Acad Sci U S A ; 117(23): 12991-12999, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32439710

RESUMO

Malignant melanoma has one of the highest mortality rates of any cancer because of its aggressive nature and high metastatic potential. Clinical staging of the disease at the time of diagnosis is very important for the prognosis and outcome of melanoma treatment. In this study, we designed and synthesized the 18F-labeled pyridine-based benzamide derivatives N-(2-(dimethylamino)ethyl)-5-[18F]fluoropicolinamide ([18F]DMPY2) and N-(2-(dimethylamino)ethyl)-6-[18F]fluoronicotinamide ([18F]DMPY3) to detect primary and metastatic melanoma at an early stage and evaluated their performance in this task. [18F]DMPY2 and [18F]DMPY3 were synthesized by direct radiofluorination of the bromo precursor, and radiochemical yields were ∼15-20%. Cell uptakes of [18F]DMPY2 and [18F]DMPY3 were >103-fold and 18-fold higher, respectively, in B16F10 (mouse melanoma) cells than in negative control cells. Biodistribution studies revealed strong tumor uptake and retention of [18F]DMPY2 (24.8% injected dose per gram of tissue [ID/g] at 60 min) and [18F]DMPY3 (11.7%ID/g at 60 min) in B16F10 xenografts. MicroPET imaging of both agents demonstrated strong tumoral uptake/retention and rapid washout, resulting in excellent tumor-to-background contrast in B16F10 xenografts. In particular, [18F]DMPY2 clearly visualized almost all metastatic lesions in lung and lymph nodes, with excellent image quality. [18F]DMPY2 demonstrated a significantly higher tumor-to-liver ratio than [18F]fluorodeoxyglucose ([18F]FDG) and the previously reported benzamide tracers N-[2-(diethylamino)-ethyl]-5-[18F]fluoropicolinamide ([18F]P3BZA) and N-[2-(diethylamino)-ethyl]-4-[18F]fluorobenzamide ([18F]FBZA) in B16F10-bearing or SK-MEL-3 (human melanoma)-bearing mice. In conclusion, [18F]DMPY2 might have strong potential for the diagnosis of early stage primary and metastatic melanoma using positron emission tomography (PET).


Assuntos
Melanoma/diagnóstico por imagem , Imagem Molecular/métodos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Neoplasias Cutâneas/diagnóstico por imagem , Animais , Linhagem Celular Tumoral , Radioisótopos de Flúor/administração & dosagem , Humanos , Camundongos , Ácidos Picolínicos/administração & dosagem , Compostos Radiofarmacêuticos/química , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Am Heart J ; 235: 1-11, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33129989

RESUMO

Current clinical practice guidelines for anemia management in non-dialysis-dependent chronic kidney disease (NDD-CKD) recommend the use of erythropoiesis-stimulating agents (ESAs) as standard of care. Vadadustat, an investigational oral hypoxia-inducible factor prolyl-hydroxylase inhibitor, stimulates endogenous erythropoietin production. The PRO2TECT program comprises 2 global, Phase 3, randomized, open-label, active-controlled, sponsor-blind clinical trials to evaluate safety and efficacy of vadadustat vs darbepoetin alfa in adult patients with anemia associated with NDD-CKD. Patients recruited into the ESA-untreated NDD-CKD trial (N = 1751) had hemoglobin <10 g/dL and had not received an ESA within 8 weeks prior to inclusion in the study. Patients recruited into the ESA-treated NDD-CKD trial (N = 1725) had hemoglobin between 8 and 11 g/dL (US) or 9 and 12 g/dL (non-US) and were actively treated with an ESA for anemia associated with CKD. Trial periods in both trials include (1) correction/conversion (weeks 0-23); (2) maintenance (weeks 24-52); (3) long-term treatment (week 53 to end of treatment); and (4) safety follow-up (end-of-treatment to 4 weeks later). The primary safety endpoint is time to first adjudicated major adverse cardiovascular event, defined as all-cause mortality, nonfatal myocardial infarction, or nonfatal stroke, pooled across both trials. The primary efficacy endpoint in each trial is change in hemoglobin from baseline to primary evaluation period (weeks 24-36), comparing vadadustat vs darbepoetin alfa treatment groups. Demographics and baseline characteristics are similar among patients in both trials and broadly representative of the NDD-CKD population. These trials will help to evaluate the safety and efficacy of vadadustat for management of anemia associated with NDD-CKD.


Assuntos
Anemia/tratamento farmacológico , Glicina/análogos & derivados , Ácidos Picolínicos/administração & dosagem , Insuficiência Renal Crônica/complicações , Administração Oral , Idoso , Anemia/etiologia , Feminino , Seguimentos , Glicina/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Renal , Resultado do Tratamento
3.
Fish Physiol Biochem ; 47(2): 599-616, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33611776

RESUMO

A 60-day feeding experiment was conducted to evaluate the effects of dietary chromium (Cr) on carbohydrate utilization and growth performance of Labeo rohita fingerlings. Fishes were fed with four high carbohydrate (53%), isonitrogenous (crude protein 35%), and isocaloric (415 Kcal, 100 gm-1) experimental diets containing different levels of dietary chromium picolinate (Cr-Pic) viz.0, 400, 800, and 1200 µg kg-1 diet. Weight gain (WG%), specific growth rate (SGR), feed efficiency ratio (FER), and protein efficiency ratio (PER) were significantly increased at 800 µg kg-1 diet chromium supplementation (P < 0.05). Cr-Pic supplementation (800 µg kg-1) also significantly (P < 0.05) enhanced the protein: DNA ratio in muscle, while DNA: RNA and DNA: tissue ratios were significantly (P < 0.05) decreased indicating higher growth. Significantly higher amylase, protease, and lipase activities were recorded in 800 µg Cr-Pic kg-1 diet fed fishes (P < 0.05), while any of the experimental groups showing no significant (P > 0.05) change in hexokinase activity, indicating normal glycolysis in all. Furthermore, significant (P < 0.05) decrease of glucose-6-phospatase activity in 800 µg Cr-Pic kg-1 diet fed group, showcasing an evidence for protein-sparing action with Cr-Pic supplementation. Significantly (P < 0.05) higher serum insulin and liver glycogen in 800 µg Cr-Pic kg-1 diet fed fishes denote an improvement in carbohydrate metabolism. However, significantly (P < 0.05) higher ATPase and SOD activities were also observed when chromium supplementation was more than 800 µg kg-1 diet, indicating stress at higher level. The present study indicates that growth and carbohydrate utilization can significantly (P < 0.05) be improved by feeding the L. rohita fingerlings with Cr-Pic (800 µg kg-1 diet) supplemented diet in laboratory condition.


Assuntos
Carpas/crescimento & desenvolvimento , Carboidratos da Dieta/metabolismo , Ácidos Picolínicos/farmacologia , Ração Animal/análise , Animais , Carpas/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Ácidos Picolínicos/administração & dosagem
4.
Inflammopharmacology ; 28(2): 385-400, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31898080

RESUMO

Alzheimer's disease (AD) is prevalent in old age people and is one of the most common brain diseases. Brain insulin resistance, neuroinflammation, oxidative stress, and mitochondrial and cholinergic dysfunction are key features of the disease. In our study, streptozotocin (STZ) in a dose of 3 mg/kg was injected in male Wistar rats bilaterally through the intracerebroventricular (ICV) route on stereotaxic apparatus. Chromium picolinate (CrPic) was tested at doses of 1 mg/kg, 2 mg/kg, and 4 mg/kg, while rivastigmine (2 mg/kg) was used as reference standard drug. Cognitive dysfunction induced by STZ was assessed by behavioral tests like Morris water maze and novel object recognition test. Treatment with CrPic revealed attenuation of cognitive deficit. This was confirmed by behavioral tests, biochemical estimations of antioxidant enzymes, oxidative stress, nitrosative stress, and cholinergic and mitochondrial activity. CrPic did not change AchE activity significantly. STZ-induced neuroinflammation evident by increased TNF-α, IL-6, and CRP levels was also significantly decreased by CrPic. Dysfunctional insulin signaling after ICV-STZ was demonstrated by reduced IRS-1, PI3K, AKT, BDNF gene expression, and increased GSK-3ß, NF-κB gene expression with the help of qRT-PCR. CrPic treatment produced an improvement in insulin signaling revealed by increased gene expression of IRS-1, PI3-K, AKT, BDNF, and decreased gene expression of GSK-3ß and NF-κB. It was concluded that CrPic reversed AD pathology revealed by improved memory, reduced oxidative stress, neuroinflammation, mitochondrial dysfunction, and upregulated insulin signaling.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Disfunção Cognitiva/tratamento farmacológico , Demência/tratamento farmacológico , Ácidos Picolínicos/farmacologia , Doença de Alzheimer/fisiopatologia , Animais , Disfunção Cognitiva/fisiopatologia , Demência/fisiopatologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glicogênio Sintase Quinase 3 beta/genética , Insulina/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Ácidos Picolínicos/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Estreptozocina
5.
Nephrol Dial Transplant ; 34(1): 90-99, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29672740

RESUMO

Background: Vadadustat, an inhibitor of hypoxia-inducible factor prolyl-4-hydroxylase domain dioxygenases, is an oral investigational agent in development for the treatment of anemia secondary to chronic kidney disease. Methods: In this open-label Phase 2 trial, vadadustat was evaluated in 94 subjects receiving hemodialysis, previously maintained on epoetin alfa. Subjects were sequentially assigned to one of three vadadustat dose cohorts by starting dose: 300 mg once daily (QD), 450 mg QD or 450 mg thrice weekly (TIW). The primary endpoint was mean hemoglobin (Hb) change from pre-baseline average to midtrial (Weeks 7-8) and end-of-trial (Weeks 15-16) and was analyzed using available data (no imputation). Results: Overall, 80, 73 and 68% of subjects in the 300 mg QD, 450 mg QD, and 450 mg TIW dose cohorts respectively, completed the study. For all dose cohorts no statistically significant mean change in Hb from pre-baseline average was observed, and mean Hb concentrations-analyzed using available data-remained stable at mid- and end-of-trial. There was one subject with an Hb excursion >13 g/dL. Overall, 83% of subjects experienced an adverse event (AE); the proportion of subjects who experienced at least one AE was similar among the three dose cohorts. The most frequently reported AEs were nausea (11.7%), diarrhea (10.6%) and vomiting (9.6%). No deaths occurred during the study. No serious AEs were attributed to vadadustat. Conclusions: Vadadustat maintained mean Hb concentrations in subjects on hemodialysis previously receiving epoetin. These data support further investigation of vadadustat to assess its long-term safety and efficacy in subjects on hemodialysis.


Assuntos
Anemia/sangue , Anemia/tratamento farmacológico , Glicina/análogos & derivados , Hematínicos/administração & dosagem , Hemoglobinas/análise , Ácidos Picolínicos/administração & dosagem , Diálise Renal/métodos , Insuficiência Renal Crônica/complicações , Adolescente , Adulto , Idoso , Anemia/etiologia , Eritropoese/efeitos dos fármacos , Feminino , Glicina/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
6.
Cochrane Database Syst Rev ; 11: CD011905, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30383288

RESUMO

BACKGROUND: Vitamins and minerals have many functions in the nervous system which are important for brain health. It has been suggested that various different vitamin and mineral supplements might be useful in maintaining cognitive function and delaying the onset of dementia. In this review, we sought to examine the evidence for this in people who already had mild cognitive impairment (MCI). OBJECTIVES: To evaluate the effects of vitamin and mineral supplementation on cognitive function and the incidence of dementia in people with mild cognitive impairment. SEARCH METHODS: We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group's (CDCIG) specialised register, as well as MEDLINE, Embase, PsycINFO, CENTRAL, CINAHL, LILACs, Web of Science Core Collection, ClinicalTrials.gov, and the WHO Portal/ICTRP, from inception to 25 January 2018. SELECTION CRITERIA: We included randomised or quasi-randomised, placebo-controlled trials which evaluated orally administered vitamin or mineral supplements in participants with a diagnosis of mild cognitive impairment and which assessed the incidence of dementia or cognitive outcomes, or both. We were interested in studies applicable to the general population of older people and therefore excluded studies in which participants had severe vitamin or mineral deficiencies. DATA COLLECTION AND ANALYSIS: We sought data on our primary outcomes of dementia incidence and overall cognitive function and on secondary outcomes of episodic memory, executive function, speed of processing, quality of life, functional performance, clinical global impression, adverse events, and mortality. We conducted data collection and analysis according to standard Cochrane systematic review methods. We assessed the risk of bias of included studies using the Cochrane 'Risk of bias' assessment tool. We grouped vitamins and minerals according to their putative mechanism of action and, where we considered it to be clinically appropriate, we pooled data using random-effects methods. We used GRADE methods to assess the overall quality of evidence for each comparison and outcome. MAIN RESULTS: We included five trials with 879 participants which investigated B vitamin supplements. In four trials, the intervention was a combination of vitamins B6, B12, and folic acid; in one, it was folic acid only. Doses varied. We considered there to be some risks of performance and attrition bias and of selective outcome reporting among these trials. Our primary efficacy outcomes were the incidence of dementia and scores on measures of overall cognitive function. None of the trials reported the incidence of dementia and the evidence on overall cognitive function was of very low-quality. There was probably little or no effect of B vitamins taken for six to 24 months on episodic memory, executive function, speed of processing, or quality of life. The evidence on our other secondary clinical outcomes, including harms, was very sparse or very low-quality. There was evidence from one study that there may be a slower rate of brain atrophy over two years in participants taking B vitamins. The same study reported subgroup analyses based on the level of serum homocysteine (tHcy) at baseline and found evidence that B vitamins may improve episodic memory in those with tHcy above the median at baseline.We included one trial (n = 516) of vitamin E supplementation. Vitamin E was given as 1000 IU of alpha-tocopherol twice daily. We considered this trial to be at risk of attrition and selective reporting bias. There was probably no effect of vitamin E on the probability of progression from MCI to Alzheimer's dementia over three years (HR 1.02; 95% CI 0.74 to 1.41; n = 516; 1 study, moderate-quality evidence). There was also no evidence of an effect at intermediate time points. The available data did not allow us to conduct analyses, but the authors reported no significant effect of three years of supplementation with vitamin E on overall cognitive function, episodic memory, speed of processing, clinical global impression, functional performance, adverse events, or mortality (five deaths in each group). We considered this to be low-quality evidence.We included one trial (n = 256) of combined vitamin E and vitamin C supplementation and one trial (n = 26) of supplementation with chromium picolinate. In both cases, there was a single eligible cognitive outcome, but we considered the evidence to be very low-quality and so could not be sure of any effects. AUTHORS' CONCLUSIONS: The evidence on vitamin and mineral supplements as treatments for MCI is very limited. Three years of treatment with high-dose vitamin E probably does not reduce the risk of progression to dementia, but we have no data on this outcome for other supplements. Only B vitamins have been assessed in more than one RCT. There is no evidence for beneficial effects on cognition of supplementation with B vitamins for six to 24 months. Evidence from a single study of a reduced rate of brain atrophy in participants taking vitamin B and a beneficial effect of vitamin B on episodic memory in those with higher tHcy at baseline warrants attempted replication.


Assuntos
Ácido Ascórbico/administração & dosagem , Transtornos Cognitivos/terapia , Demência/prevenção & controle , Suplementos Nutricionais , Oligoelementos/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Vitaminas/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Cognição/fisiologia , Função Executiva , Humanos , Memória Episódica , Pessoa de Meia-Idade , Mortalidade , Ácidos Picolínicos/administração & dosagem , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , alfa-Tocoferol/administração & dosagem
7.
Nano Lett ; 17(6): 3822-3829, 2017 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-28488871

RESUMO

Chemoimmunotherapy, which combines chemotherapeutics with immune-modulating agents, represents an appealing approach for improving cancer therapy. To optimize its therapeutic efficacy, differentially delivering multiple therapeutic drugs to target cells is desirable. Here we developed an immunostimulatory nanocarrier (denoted as BLZ-945SCNs/Pt) that could spatially target tumor-associated macrophages (TAMs) and tumor cells for cancer chemoimmunotherapy. BLZ-945SCNs/Pt undergo supersensitive structure collapse in the prevascular regions of tumor tissues and enable the simultaneous release of platinum (Pt)-prodrug conjugated small particles and BLZ-945, a small molecule inhibitor of colony stimulating factor 1 receptor (CSF-1R) of TAMs. The released BLZ-945 can be preferentially taken up by TAMs to cause TAMs depletion from tumor tissues, while the small particles carrying Pt-prodrug enable deep tumor penetration as well as intracellularly specific drug release to kill more cancer cells. Our studies demonstrate that BLZ-945SCNs/Pt outperform their monotherapy counterparts in multiple tumor models. The underlying mechanism studies suggest that the designer pH-sensitive codelivery nanocarrier not only induces apoptosis of tumor cells but also modulates the tumor immune environment to eventually augment the antitumor effect of CD8+ cytotoxic T cells through TAMs depletion.


Assuntos
Antineoplásicos/química , Portadores de Fármacos/química , Macrófagos/efeitos dos fármacos , Nanopartículas/química , Animais , Antineoplásicos/administração & dosagem , Apoptose , Benzotiazóis/administração & dosagem , Benzotiazóis/química , Linhagem Celular Tumoral , Terapia Combinada , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Imunoterapia/métodos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Ácidos Picolínicos/administração & dosagem , Ácidos Picolínicos/química , Platina/química , Polímeros/química , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química , Propriedades de Superfície , Microambiente Tumoral
8.
J Sci Food Agric ; 98(1): 74-79, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28523848

RESUMO

BACKGROUND: The present study investigated the effects of dietary supplementation of l-arginine and chromium picolinate (CrP) in sows during gestation on muscle fibre characteristics, performance and carcass characteristics of their progeny. Sixty healthy sows were randomly divided into four groups as a 2 × 2 factorial experiment design: one group received the control diet, another received the control diet + 10 g kg-1 l-arginine, the third group received the control diet + 400 ppb CrP, and the fourth group received the control diet + 10 g kg-1 l-arginine and 400 ppb CrP. RESULTS: The results showed that sows fed the diet supplemented with CrP produced progeny with higher muscle fibre numbers at birth, weaning and slaughter compared to sows fed the control diet. For mean fibre areas, the same result was found at weaning. For progeny of sows fed diets supplemented with l-arginine, only higher muscle fibre numbers at slaughter was observed. Almost no differences were observed regarding average daily gains, average daily feed intake, gain-to-feed ratios, carcass and meat traits. CONCLUSION: The results of the present study indicate that dietary supplementation of l-arginine and particularly CrP in sows during gestation alters muscle fibre numbers in their offspring, although not their performance or carcass characteristics. © 2017 Society of Chemical Industry.


Assuntos
Arginina/administração & dosagem , Suplementos Nutricionais/análise , Fibras Musculares Esqueléticas/metabolismo , Ácidos Picolínicos/administração & dosagem , Gravidez/metabolismo , Suínos/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Peso ao Nascer , Feminino , Masculino , Carne/análise , Fibras Musculares Esqueléticas/efeitos dos fármacos , Gravidez/efeitos dos fármacos , Suínos/crescimento & desenvolvimento
9.
Fish Physiol Biochem ; 44(5): 1265-1274, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29961187

RESUMO

A feeding trial was conducted to evaluate the effects of chromium picolinate (Cr-Pic) on growth performance, body composition, and biochemical parameters in Nile tilapia Oreochromis niloticus. Five experimental diets were formulated with high-protein diet (HP), low-protein diet (LP), and LP + 0.6, 1.2, or 1.8 mg kg-1 Cr, respectively. Each diet was randomly assigned to four replicate groups of 30 fish per aquarium in a water-circulated rearing system for 60 days. Dietary 1.2 or 1.8 mg kg-1 Cr inclusion significantly affects the final body weight, weight gain rate, specific growth rate, feed efficiency rate, and protein efficiency ratio of tilapia compare to the LP diet. The Cr inclusion significantly decreased the content of blood urea nitrogen and the blood glucose level generally with increasing Cr inclusion levels. The Cr content of gill tissue was higher than that of back muscle in all treatments, and the addition of 1.2 or 1.8 mg kg-1 Cr significantly enhanced the Cr contents of back muscle. The cold stress test results showed that adding Cr significantly enhanced the serum T3 concentration and reduced the activity of serum creatine kinase and the serum cortisol level. These results indicated that the supplementation of chromium picolinate can improve the growth performance and reshape the serum protein and carbohydrate metabolism profile and has the potentiality to alleviate the detrimental effects of cold stress in Nile tilapia. The low-protein diet with 1.8 mg kg-1 Cr obtained the same growth performance as the high-protein diet.


Assuntos
Ração Animal/análise , Composição Corporal/efeitos dos fármacos , Ciclídeos/crescimento & desenvolvimento , Suplementos Nutricionais , Ácidos Picolínicos/farmacologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Aquicultura , Ciclídeos/sangue , Dieta/veterinária , Relação Dose-Resposta a Droga , Ácidos Picolínicos/administração & dosagem
10.
Mol Pharm ; 14(1): 147-156, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-28043132

RESUMO

Here we used a lipid-soluble Zn(II)-bis-dipicolylamine derivative as a membrane component to develop liposomal carriers that have potential to be targeted to phosphatidylserine (PS) rich surfaces on cancer cells and to preferentially kill cancer cells without using anticancer drugs. This DPA derivative (abbreviated as DPA-Cy3[22,22]) contains the fluorophore cyanine 3 (Cy3) and two 22-carbon chains that can be anchored into liposomal membrane bilayers. DPA-Cy3[22,22]/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) unilamellar vesicles (∼150 nm) showed selective binding to PS-containing liposomes as demonstrated by anion exchange chromatography. This binding does not result in vesicle fusion or aggregation. Flow cytometry showed that DPA-Cy3[22,22]/POPC liposomes have preferential binding to MCF-7 breast cancer cells over MCF-12A noncancer cells due to 3-7 times more PS exposures on MCF-7. The extent of liposome binding with MCF-7 cells was increased by two times after cells were pretreated with the apoptotic inducer camptothecin, which increased PS exposure to the cell surface. Moreover, our flow cytometry data also suggest that local cell membrane perturbations may occur upon liposome binding and internalization. This implies that DPA-Cy3[22,22]/POPC liposomes alone may have a PS-dependent cytotoxic effect. This assertion was supported by the cell proliferation assay, which showed that 9.1 mol % DPA-Cy3[22,22]/POPC liposomes exert cytotoxicity on MCF-7 cells 3.5 times higher than that on MCF-12A cells. These results indicate that DPA-Cy3[22,22]-containing liposomes hold great promise as efficient nano drug carriers.


Assuntos
Aminas/administração & dosagem , Aminas/química , Membrana Celular/efeitos dos fármacos , Lipossomos/química , Neoplasias/tratamento farmacológico , Fosfatidilserinas/metabolismo , Ácidos Picolínicos/administração & dosagem , Ácidos Picolínicos/química , Zinco/química , Ânions/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos/química , Humanos , Bicamadas Lipídicas/química , Lipossomos/administração & dosagem , Células MCF-7 , Fusão de Membrana/efeitos dos fármacos , Nanopartículas/administração & dosagem , Nanopartículas/química , Fosfatidilcolinas/química , Lipossomas Unilamelares/química , Zinco/administração & dosagem
11.
J Obstet Gynaecol Res ; 42(3): 279-85, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26663540

RESUMO

AIM: To investigate the effect of chromium picolinate (CrP) on insulin resistance (IR) in polycystic ovary syndrome (PCOS). METHODS: This double blinded randomized controlled trial was conducted in the Gynecology outpatient clinics at Ain Shams University Women's Hospital. Using closed and randomly mixed envelopes, 100 women were selected out of 400 PCOS patients. Eighty-five patients finished the study and were analyzed, 44 in group I and 41 in group II. They were randomly allocated to 6 months of either 1000 µg CrP (50 patients), or placebo capsules (50 patients). Patients were seen monthly to encourage similar diet control and physical exercise plans. The primary outcome was fasting glucose insulin ratio (FGIR), secondary outcomes included ovulation, regularity of the cycle, body mass index (BMI), fasting blood sugar (FBS), fasting serum insulin (FSI), and serum testosterone level. RESULTS: There were no significant differences between women of both groups regarding pretreatment levels of FBS, FSI, FGIR, and serum testosterone. Use of CrP for 6 months was associated with significant reduction of BMI (P < 0.001) and FSI (P = 0.007), and significant rise in FGIR (P = 0.045). CrP significantly increased the chances of ovulation (P = 0.011) and regular menstruation (P = 0.002) by almost twofold after the fifth month of treatment. CONCLUSION: Chromium picolinate is useful in PCOS to reduce IR and stimulate ovulation.


Assuntos
Suplementos Nutricionais , Resistência à Insulina , Avaliação de Resultados em Cuidados de Saúde , Ácidos Picolínicos/farmacologia , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/metabolismo , Adulto , Feminino , Humanos , Ácidos Picolínicos/administração & dosagem , Adulto Jovem
12.
Vopr Pitan ; 85(2): 51-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27455600

RESUMO

The aim of this study was to evaluate the influence of chromium supplements on the quality of protein and lipids of adipose anatomical parts using pig as experimental modelfor humans. An experiment was conducted on 18 fattening castrated TOPIGS male pigs, for 4 weeks, under experimental farm conditions. The source of Cr(III) was chromium . picolinate, a food supplement used in human nutrition, 200 µg.Cr per kg diet (El) and 400 µg.Cr per kg diet (E2). The analytic.data showed an improvement of the amino acids profile in belly and in ham samples. A significant decrease of fatty acids concentrations in belly samples was noticed. In conclusion, we observed a positive effect associated with the essential amino acids deposition and decreasing of fatty acids concentrations in tissues with high content offat, thus in human nutrition, chromium is used as a nutritional supplement most recommended in impaired carbohydrate metabolism.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Cromo/farmacologia , Compostos Organometálicos/farmacologia , Ácidos Picolínicos/farmacologia , Sus scrofa/crescimento & desenvolvimento , Tecido Adiposo/crescimento & desenvolvimento , Tecido Adiposo/metabolismo , Aminoácidos/análise , Animais , Cromo/administração & dosagem , Suplementos Nutricionais , Ácidos Graxos/análise , Masculino , Compostos Organometálicos/administração & dosagem , Ácidos Picolínicos/administração & dosagem , Sus scrofa/metabolismo
13.
Bioorg Med Chem Lett ; 24(15): 3307-14, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24969015

RESUMO

Development of SAR in an aryl ether series of mGlu5 NAMs leading to the identification of pyrazine analog VU0431316 is described in this Letter. VU0431316 is a potent and selective non-competitive antagonist of mGlu5 that binds at a known allosteric binding site. VU0431316 demonstrates an attractive DMPK profile, including moderate clearance and good bioavailability in rats. Intraperitoneal (IP) dosing of VU0431316 in a mouse marble burying model of anxiety, an assay known to be sensitive to mGlu5 antagonists and other anxiolytics, produced dose proportional effects.


Assuntos
Ansiedade/tratamento farmacológico , Modelos Animais de Doenças , Descoberta de Drogas , Ácidos Picolínicos/farmacologia , Pirazinas/farmacologia , Receptor de Glutamato Metabotrópico 5/antagonistas & inibidores , Sítio Alostérico/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Humanos , Masculino , Camundongos , Estrutura Molecular , Ácidos Picolínicos/administração & dosagem , Ácidos Picolínicos/química , Pirazinas/administração & dosagem , Pirazinas/química , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
14.
PLoS One ; 19(5): e0300292, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38718051

RESUMO

The aim of the study was to investigate the effect of returning to a balanced diet combined with chromium picolinate (CrPic) or chromium nanoparticles (CrNPs) supplementation at a pharmacologically relevant dose of 0.3 mg/kg body weight on the expression level of selected genes and bone turnover markers in the blood and bones of rats fed an obese diet. The results of the study showed that chronic intake of a high-fat obesogenic diet negatively affects bone turnover by impairing processes of both synthesis and degradation of bones. The switch to a healthy diet proved insufficient to regulate bone metabolism disorders induced by an obesogenic diet, even when it was supplemented with chromium, irrespective of its form. Supplementation with CrPic with no change in diet stimulated bone metabolism only at the molecular level, towards increased osteoclastogenesis (bone resorption). In contrast, CrNPs added to the high-fat diet effectively regulated bone turnover by increasing both osteoblastogenesis and osteoclastogenesis, with these changes directed more towards bone formation. The results of the study suggest that unfavourable changes in bone metabolism induced by chronic intake of a high-fat diet can be mitigated by supplementation with CrNPs, whereas a change in eating habits fails to achieve a similar effect.


Assuntos
Remodelação Óssea , Cromo , Dieta Hiperlipídica , Animais , Dieta Hiperlipídica/efeitos adversos , Ratos , Cromo/administração & dosagem , Cromo/farmacologia , Masculino , Remodelação Óssea/efeitos dos fármacos , Nanopartículas/química , Fibras na Dieta/farmacologia , Ácidos Picolínicos/farmacologia , Ácidos Picolínicos/administração & dosagem , Suplementos Nutricionais , Osso e Ossos/metabolismo , Osso e Ossos/efeitos dos fármacos , Ratos Wistar , Nanopartículas Metálicas/química , Nanopartículas Metálicas/administração & dosagem , Osteogênese/efeitos dos fármacos
15.
Cochrane Database Syst Rev ; (11): CD010063, 2013 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-24293292

RESUMO

BACKGROUND: Obesity is a global public health threat. Chromium picolinate (CrP) is advocated in the medical literature for the reduction of bodyweight, and preparations are sold as slimming aids in the USA and Europe, and on the Internet. OBJECTIVES: To assess the effects of CrP supplementation in overweight or obese people. SEARCH METHODS: We searched The Cochrane Library, MEDLINE, EMBASE, ISI Web of Knowledge, the Chinese Biomedical Literature Database, the China Journal Full text Database and the Chinese Scientific Journals Full text Database (all databases to December 2012), as well as other sources (including databases of ongoing trials, clinical trials registers and reference lists). SELECTION CRITERIA: We included trials if they were randomised controlled trials (RCT) of CrP supplementation in people who were overweight or obese.We excluded studies including children, pregnant women or individuals with serious medical conditions. DATA COLLECTION AND ANALYSIS: Two authors independently screened titles and abstracts for relevance. Screening for inclusion, data extraction and 'Risk of bias'assessment were carried out by one author and checked by a second. We assessed the risk of bias by evaluating the domains selection,performance, attrition, detection and reporting bias. We performed a meta-analysis of included trials using Review Manager 5. MAIN RESULTS: We evaluated nine RCTs involving a total of 622 participants. The RCTs were conducted in the community setting, with interventions mainly delivered by health professionals, and had a short- to medium-term follow up (up to 24 weeks). Three RCTs compared CrPplus resistance or weight training with placebo plus resistance or weight training, the other RCTs compared CrP alone versus placebo.We focused this review on investigating which dose of CrP would prove most effective versus placebo and therefore assessed the results according to CrP dose. However, in order to find out if CrP works in general, we also analysed the effect of all pooled CrP doses versus placebo on body weight only.Across all CrP doses investigated (200 µg, 400 µg, 500 µg, 1000 µg) we noted an effect on body weight in favour of CrP of debatable clinical relevance after 12 to 16 weeks of treatment: mean difference (MD) -1.1 kg (95% CI -1.7 to -0.4); P = 0.001; 392 participants;6 trials; low-quality evidence (GRADE)). No firm evidence and no dose gradient could be established when comparing different doses of CrP with placebo for various weight loss measures (body weight, body mass index, percentage body fat composition, change in waist circumference).Only three studies provided information on adverse events (low-quality evidence (GRADE)). There were two serious adverse events and study dropouts in participants taking 1000 µg CrP, and one serious adverse event in an individual taking 400 µg CrP. Two participants receiving placebo discontinued due to adverse events; one event was reported as serious. No study reported on all-cause mortality,morbidity, health-related quality of life or socioeconomic effects. AUTHORS' CONCLUSIONS: We found no current, reliable evidence to inform firm decisions about the efficacy and safety of CrP supplements in overweight or obese adults.


Assuntos
Suplementos Nutricionais , Obesidade/tratamento farmacológico , Ácidos Picolínicos/administração & dosagem , Adulto , Humanos , Sobrepeso/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Treinamento Resistido , Levantamento de Peso , Redução de Peso
16.
Exp Mol Pathol ; 92(1): 54-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21983138

RESUMO

Hallmark features of type 2 diabetes mellitus include glucosuria and polyuria. Further, renal aquaporin 2 is pivotal to regulation of fluid excretion and urine osmolality. Accordingly, we tested the hypothesis that the db/db mouse displays increased glucosuria and fluid excretion but reduced urine osmolality in association with decreased renal aquaporin 2 level. In addition, we examined the effect of chromium picolinate (Cr(pic)3) which is purported to improve glycemic control. The db/db mice excreted more urine in association with marked glucose excretion but lower urine osmolality than db/m control group. Light microscopic examination of renal tissue revealed proliferation of tubular structures in db/db compared to the db/m mice, a feature validated with Ki67 immunostaining. Further, these tubules showed generally similar immunostaining intensity and pattern for aquaporin 2 indicating that proliferated tubules are of distal origin. On the other hand, renal aquaporin 2 protein level was significantly higher in the db/db than db/m group. Treatment of db/db mice with Cr(pic)3 reduced plasma glucose and hemoglobin A1c (~15-17%, p<0.05) and Ki67 positive cells but other parameters were similar to their untreated counterparts. Collectively, these findings suggest that proliferation of renal distal tubules and increased aquaporin 2 level likely represent an adaptive mechanism to regulate fluid excretion to prevent dehydration in the setting of marked glucosuria in the db/db mouse, features not affected by Cr(pic)3 treatment. These observations are of relevance to increasing interest in developing therapeutic agents that facilitate renal glucose elimination.


Assuntos
Aquaporina 2/urina , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Túbulos Renais Distais/patologia , Ácidos Picolínicos/administração & dosagem , Animais , Transporte Biológico/efeitos dos fármacos , Glicemia/análise , Peso Corporal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Desidratação/prevenção & controle , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/urina , Modelos Animais de Doenças , Índice Glicêmico/efeitos dos fármacos , Glicosúria , Insulina/sangue , Antígeno Ki-67/análise , Antígeno Ki-67/efeitos dos fármacos , Masculino , Camundongos , Concentração Osmolar , Poliúria/urina , Distribuição Aleatória
17.
Biometals ; 25(5): 1051-60, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22814636

RESUMO

Chromium(III) is long regarded as essential trace element but the biochemical function and even basic transport ways in the body are still unclear. For a more rational discussion on beneficial as well as toxic effects of Cr(III), we re-investigated the bioavailability of the most important oral Cr supplements by using radiolabeled compounds and whole-body-counting in rats and in the first time also in humans. The apparent absorption of (51)Cr(III) from Cr-picolinate, Cr-nicotinate, Cr-phenylalaninate, Cr-proprionate, or Cr-chloride was generally low (0.04-0.24 %) in rats with slightly higher values for Cr-chloride and -phenylalaninate. Taking a fast urine excretion into account, the true absorption of (51)Cr was clearly higher for CrPic(3) (0.99 %), probably indicating a different uptake mechanism of this rather stable organic Cr complex. The bioavailability of CrPic(3) and Cr(D: -Phen)(3), the leading compounds in actual investigations, was analysed also in human volunteer by intraindividual comparison. The apparent absorption (=Cr bioavailability) of (51)Cr from both compounds was substantially higher in humans (0.8-1 %) than in rats. Again, most of freshly absorbed CrPic(3) was excreted into the urine resulting in the same low whole-body retention after 7 days for both compounds. In summary, the bioavailability of Cr from pharmaceutical Cr compound is lower than hitherto assumed. Importantly, humans absorb Cr(III) clearly better than rats. The absorption mechanism of CrPic(3) seems to be different from ionic Cr(III) but, as only the same low amount of Cr is retained from this compound, it is also not more bioavailable than other Cr compounds.


Assuntos
Cromo/farmacocinética , Compostos Organometálicos/farmacocinética , Administração Oral , Idoso , Animais , Disponibilidade Biológica , Cromo/administração & dosagem , Radioisótopos de Cromo/administração & dosagem , Radioisótopos de Cromo/farmacocinética , Suplementos Nutricionais , Feminino , Humanos , Injeções Intraperitoneais , Injeções Intravenosas , Absorção Intestinal , Pessoa de Meia-Idade , Ácidos Nicotínicos/administração & dosagem , Ácidos Nicotínicos/farmacocinética , Compostos Organometálicos/administração & dosagem , Fenilalanina/administração & dosagem , Fenilalanina/análogos & derivados , Fenilalanina/farmacocinética , Ácidos Picolínicos/administração & dosagem , Ácidos Picolínicos/farmacocinética , Ratos , Ratos Wistar
18.
J Neural Transm (Vienna) ; 118(12): 1703-16, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21161716

RESUMO

Subtype 5 metabotropic glutamate receptors (mGluR5) are abundant in the basal ganglia, amygdala, septum, hippocampus, peripheral sensory neurones and dorsal horn of the spinal cord. Thus, mGluR5 has been implicated in central processes underlying movement control, emotion, learning, and nociception. Different negative allosteric modulators (NAMs) of mGluR5 were repeatedly shown to be efficacious in models of L: -DOPA-induced dyskinesia (LID), anxiety, and some forms of pain. MRZ-8676 (6,6-dimethyl-2-phenylethynyl-7,8-dihydro-6H-quinolin-5-one) is a novel proprietary, selective, orally bioavailable mGluR5 NAM. MRZ-8676 (8.33, 25 and 75 mg/kg) showed a high efficacy in the rat model of LID, with the maximal effect size reaching ~80%. The antidyskinetic effects of MRZ-8676 (75 mg/kg) did not show tolerance as assessed after repetitive (6 days) treatment. MRZ-8676 (25 or 75 mg/kg) demonstrated moderate efficacy in two rat models of anxiety-contextual fear conditioning and the elevated plus maze. MRZ-8676 (25 mg/kg) was also effective in the formalin test, a rat model of persistent pain. The efficacious doses of MRZ-8676 did not produce any detrimental effects on motor performance of rats as determined by means of automated open field and rotarod. However, high doses of MRZ-8676 (75 or 150 mg/kg) disrupted learning in an aversive learning paradigm of the contextual fear conditioning test. In conclusion, MRZ-8676 is a new investigational agent with an efficacy profile similar to the widely published reference mGluR5 NAMs. The drug was demonstrated to possess a superior antidyskinetic efficacy with a sufficient therapeutic window. MRZ-8676 has also therapeutic potential as an anxiolytic and analgesic drug.


Assuntos
Discinesia Induzida por Medicamentos/tratamento farmacológico , Antagonistas de Aminoácidos Excitatórios/química , Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Adrenérgicos/toxicidade , Regulação Alostérica/efeitos dos fármacos , Análise de Variância , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cálcio/metabolismo , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/etiologia , Condicionamento Psicológico/efeitos dos fármacos , Modelos Animais de Doenças , Dopaminérgicos/efeitos adversos , Relação Dose-Resposta a Droga , Discinesia Induzida por Medicamentos/complicações , Discinesia Induzida por Medicamentos/etiologia , Discinesia Induzida por Medicamentos/patologia , Medo/efeitos dos fármacos , Técnicas In Vitro , Levodopa/efeitos adversos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Microdiálise , Inibidores da Monoaminoxidase/administração & dosagem , Atividade Motora/efeitos dos fármacos , Oxidopamina/toxicidade , Medição da Dor , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/tratamento farmacológico , Ácidos Picolínicos/administração & dosagem , Desempenho Psicomotor/efeitos dos fármacos , Quinolonas/química , Quinolonas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Receptor de Glutamato Metabotrópico 5 , Receptores de Glutamato Metabotrópico/metabolismo , Teste de Desempenho do Rota-Rod , Espectrometria de Massas em Tandem/métodos , Fatores de Tempo
19.
PLoS One ; 16(4): e0249527, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33822801

RESUMO

OBJECTIVE: A meta-analysis was conducted to assess the effects of dietary chromium picolinate (CrPic) supplementation on broiler growth performance and to determine whether such effects are regulated by broiler strains, sex, environmental stress, or contextual factors including study area and years. METHODS: Eligible studies were identified by searching the Web of Science, Springer, Elsevier, ScienceDirect, Taylor & Francis Online databases. Weighted average differences with corresponding 95% confidence intervals were computed with a random-effects model. We performed subgroup analysis stratified by study area, published years, broiler strains and sex, and environmental stress. Publication bias was assessed with Egger's test method. A total of 15 studies eligible for inclusion. RESULTS: The results indicated that CrPic supplementation significantly improved broiler growth performance and subgroup analysis confirmed this conclusion. We also found that Ross 308 or male broilers might be more sensitive to CrPic supplementation and showed better growth performance. A model was used to obtain the amount of chromium addition under the optimal growth performance, which suggested that the maximum value of average daily gain (ADG) was reached when chromium addition was 1810 µg/kg. The results of the sensitivity analysis showed low sensitivity and high stability of the meta-analysis. CONCLUSIONS: CrPic supplementation had a positive effect on the growth performance of broilers, and this meta-analysis provides a more accurate value of chromium addition, which may be beneficial for the practice of the broiler industry.


Assuntos
Ração Animal/análise , Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais , Quelantes de Ferro/administração & dosagem , Ácidos Picolínicos/administração & dosagem , Animais
20.
Toxicology ; 462: 152960, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34555453

RESUMO

Picolinic acid (PIC) is a byproduct of tryptophan catabolism through the kynurenine pathway, with anabolic effects on bone in vivo and in vitro. Hence, PIC has been nominated as a possible candidate to treat and/or prevent osteoporosis. However, the effective dose and toxicity of PIC are not known yet. To test the effect of escalating and very high doses of oral PIC, male Sprague-Dawley rats were gavaged PIC: Group 1 (n = 3) received incremental doses of 125, 250 and 500 mg/kg/day PIC on days 1, 3 and 5. Group 2 (n = 3) received 500 mg/kg BID (8 h apart; i.e. 1000 mg/kg/day) PIC on Day 1. Group 3 (n = 3) received 125 mg/kg/day PIC for seven consecutive days. Group 4 (n = 3) received 250 mg/kg/day PIC for seven consecutive days. Groups 1, 3 and 4 rats were euthanized on Day 8. Group 5 (n = 6) received 500 mg/kg/day PIC for two consecutive days and then once a week dose (Days 9, 16 and 23) of 500 mg/kg/dose PIC, until euthanasia (Day 30). Blood and cerebrospinal fluid (CSF) were sampled at euthanasia, and tissues showing abnormalities at necropsy underwent histopathology evaluation. All rats displayed some degree of mild hypercalcemia and hyperkalemia. Rats receiving high doses (500 or 1000 mg/kg/day) of PIC died or were euthanized on humane grounds within the first week after showing clinical neurological signs, with animals later revealed to have brain necrosis and hemorrhage at histopathology. Rats receiving lower doses (125 or 250 mg/kg/day) of PIC completed treatment course without apparent clinical adverse events. In summary, very high doses of PIC (≥500 mg/kg/day) were vascular-neurotoxic. Possible future experiments must consider significantly lower doses.


Assuntos
Hiperpotassemia/induzido quimicamente , Síndromes Neurotóxicas/etiologia , Ácidos Picolínicos/toxicidade , Animais , Relação Dose-Resposta a Droga , Hipercalcemia/induzido quimicamente , Masculino , Síndromes Neurotóxicas/fisiopatologia , Ácidos Picolínicos/administração & dosagem , Ratos , Ratos Sprague-Dawley
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