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Adverse cardiac outcomes in COVID-19 patients, particularly those with preexisting cardiac disease, motivate the development of human cell-based organ-on-a-chip models to recapitulate cardiac injury and dysfunction and for screening of cardioprotective therapeutics. Here, we developed a heart-on-a-chip model to study the pathogenesis of SARS-CoV-2 in healthy myocardium established from human induced pluripotent stem cell (iPSC)-derived cardiomyocytes and a cardiac dysfunction model, mimicking aspects of preexisting hypertensive disease induced by angiotensin II (Ang II). We recapitulated cytopathic features of SARS-CoV-2-induced cardiac damage, including progressively impaired contractile function and calcium handling, apoptosis, and sarcomere disarray. SARS-CoV-2 presence in Ang II-treated hearts-on-a-chip decreased contractile force with earlier onset of contractile dysfunction and profoundly enhanced inflammatory cytokines compared to SARS-CoV-2 alone. Toward the development of potential therapeutics, we evaluated the cardioprotective effects of extracellular vesicles (EVs) from human iPSC which alleviated the impairment of contractile force, decreased apoptosis, reduced the disruption of sarcomeric proteins, and enhanced beta-oxidation gene expression. Viral load was not affected by either Ang II or EV treatment. We identified MicroRNAs miR-20a-5p and miR-19a-3p as potential mediators of cardioprotective effects of these EVs.
Assuntos
Angiotensina II , COVID-19 , Células-Tronco Pluripotentes Induzidas , Dispositivos Lab-On-A-Chip , Miócitos Cardíacos , Humanos , Angiotensina II/farmacologia , Apoptose/efeitos dos fármacos , COVID-19/virologia , COVID-19/metabolismo , Citocinas/metabolismo , Vesículas Extracelulares/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , MicroRNAs/metabolismo , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/virologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , SARS-CoV-2/fisiologiaRESUMO
BACKGROUND: Current evidence on associations between circulating bilirubin and colorectal cancer (CRC) risk is inconsistent. METHODS: In this prospective study, we investigated associations of pre-diagnostic circulating levels of total and indirect bilirubin with CRC risk in 78,467 Korean adults aged 40-78 years at recruitment, considering potential non-linearity and sex differences. Hazard ratios (HR) and 95% confidence intervals (CI) for associations with CRC risk were estimated with Cox proportional hazard regression. RESULTS: During a median 7.9-year follow-up, 539 incident CRC cases were recorded. In multivariable-adjusted models, higher levels of total bilirubin were associated with a 26% (CI: 42% to 7%) lower risk of CRC among men and women combined, comparing the highest with the lowest tertile (P-linear trend = 0.003). A U-shaped association was observed in men, with the lowest risk at approximately 0.8 mg/dL (=13.7 µmol/L) of total bilirubin (P for non-linearity = 0.01). Although the association was largely null in women, there was no evidence for effect modification by sex (P-interaction = 0.73). Associations between indirect bilirubin and CRC risk were similar. CONCLUSIONS: Higher circulating levels of total and indirect bilirubin were inversely associated with the risk of CRC among Korean adults. The associations were strongly inverse and U-shaped among men.
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PURPOSE: Vitamin D status and its association with age-related decline in physical performance and strength have already been highlighted in various ways, but data on the situation in developing countries are scarce. This study aimed to investigate vitamin D status, its association with muscle mass and function, and other potential determinants such as age, sex, lifestyle factors (physical activity, dietary behavior), self-perceived health status, medication intake, education and financial situation in adults from Kosovo. METHODS: This cross-sectional study included 297 participants (54.5% women), aged ≥ 40 years. Serum 25-hydroxyvitamin D (25(OH)D) concentration, hand grip strength and physical performance tests, body composition, vitamin D dietary intake and knowledge were assessed. The interaction between serum 25(OH)D status, lifestyle factors and muscle traits was investigated. RESULTS: Vitamin D deficiency (< 50 nmol/L) was observed in 47.5% of the total population, of whom 14.7% of them were severely deficient (< 30 nmol/L). No associations were found between 25(OH)D concentration and age. Daily dietary intake of vitamin D was low (1.89 ± 0.67 µg) and 87.6% of individuals did not take vitamin D supplements. However, vitamin D supplementation was the only variable that added statistical significance (p < 0.05) to the prediction of vitamin D status (3.8%). On the other hand, age, medication intake and vitamin D level contributed significantly to the overall regression model, explaining 24.9% of the 30-s chair stand performance as an indicator of lower-body strength endurance. CONCLUSION: Vitamin D deficiency is highly prevalent among community-dwelling adults in Kosovo and low serum 25(OH)D has been associated with low muscle strength. This implies an urgent need for the development of comprehensive prevention strategies, focusing on pharmacological (supplementation) but also on non-pharmacological strategies such as education, food fortification or lifestyle advices.
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Força da Mão , Deficiência de Vitamina D , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Estudos Transversais , Vida Independente , Vitamina D , Vitaminas , Suplementos Nutricionais , Desempenho Físico Funcional , Estilo de VidaRESUMO
Mesoporous silica offers an easy way to transform liquids into solids, due to their high loading capacity for liquid or dissolved active ingredients and the resulting enhanced dissolution properties. However, the compression of both unloaded and loaded mesoporous silica bulk material into tablets is challenging, due to poor/non-existing binding capacity. This becomes critical when high drug loads are to be achieved and the fraction of additional excipients in the final tablet formulation needs to be kept at a minimum. Our study aimed to investigate the mechanism of compression and tabletability dependent on the Liquid Load Level of the silica and type of filler/binder in binary tabletting mixtures. To this end, Vivapur® 101, FlowLac® 90, Pearlitol® 200 SD and tricalcium citrate tetrahydrate were selected and mixed with Syloid® XDP 3050 at various Liquid Load Levels. Compaction characteristics were analysed using the StylOne® Classic 105 ML compaction simulator. Additionally, the Overall Liquid Load (OLL) was defined as a new critical quality attribute for liquisolid tablets. The Overall Liquid Load allows straightforward, formulation-relevant comparisons between various fillers/binders, liquid components, and silica types. Results indicate strong binding capacity and high plasticity of the fillers/binders as key components for successful high liquid load silica tablet formulation. A volumetric combination of 30% Vivapur® 101 and 70% 0.75 mL/g loaded Syloid® XDP 3050 proved to be the most effective mixture, achieving an Overall Liquid Load of 36-41% [v/v] and maintaining a tensile strength of 1.5 N/mm2 with various liquid vehicles.
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Composição de Medicamentos , Excipientes , Dióxido de Silício , Comprimidos , Comprimidos/química , Dióxido de Silício/química , Excipientes/química , Porosidade , Composição de Medicamentos/métodos , Química Farmacêutica/métodos , SolubilidadeRESUMO
The success of obtaining solid dispersions for solubility improvement invariably depends on the miscibility of the drug and polymeric carriers. This study aimed to categorize and select polymeric carriers via the classical group contribution method using the multivariate analysis of the calculated solubility parameter of RX-HCl. The total, partial, and derivate parameters for RX-HCl were calculated. The data were compared with the results of excipients (N = 36), and a hierarchical clustering analysis was further performed. Solid dispersions of selected polymers in different drug loads were produced using solvent casting and characterized via X-ray diffraction, infrared spectroscopy and scanning electron microscopy. RX-HCl presented a Hansen solubility parameter (HSP) of 23.52 MPa1/2. The exploratory analysis of HSP and relative energy difference (RED) elicited a classification for miscible (n = 11), partially miscible (n = 15), and immiscible (n = 10) combinations. The experimental validation followed by a principal component regression exhibited a significant correlation between the crystallinity reduction and calculated parameters, whereas the spectroscopic evaluation highlighted the hydrogen-bonding contribution towards amorphization. The systematic approach presented a high discrimination ability, contributing to optimal excipient selection for the obtention of solid solutions of RX-HCl.
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Química Farmacêutica , Excipientes , Polímeros , Cloridrato de Raloxifeno , Solubilidade , Difração de Raios X , Polímeros/química , Excipientes/química , Cloridrato de Raloxifeno/química , Análise Multivariada , Difração de Raios X/métodos , Química Farmacêutica/métodos , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Microscopia Eletrônica de Varredura/métodos , Ligação de Hidrogênio , Cristalização/métodosRESUMO
PURPOSE: Gastric atrophy (GA), usually linked to chronic infection with Helicobacter pylori (H. pylori), may over time evolve into gastric malignancy. Besides H. pylori, high salt intake may play a role in GA development. This study evaluates cross sectionally the association between salt intake and GA in Chilean adults. METHODS: Population-based samples were recruited from two sites, Antofagasta and Valdivia, partaking in the Epidemiological Investigation of Gastric Malignancies. At recruitment, participants answered questionnaires and provided biospecimens. Salt intake (g/day) was estimated from casual spot urine samples using the Tanaka equation. GA was determined by serum pepsinogen levels. Only participants ≥ 40 to 70 years of age were considered in this analysis, n = 565. For the association between salt intake (as sex-specific quartiles) and GA, odds ratios (ORs) and the corresponding 95% confidence intervals (CI) were estimated through multivariable logistic regression. RESULTS: In women, the multivariable-adjusted OR for GA comparing quartile 4 of the estimated salt intake (12.8 g/day) to quartile 1 (6.6 g/day) was 1.18 (95% CI 0.52-2.68, P-trend = 0.87). The corresponding OR in men was 0.49 (95% CI 0.19-1.27, P-trend = 0.17) with salt intakes of 12.8 g/day and 7.1 g/day for quartiles 4 and 1, respectively. CONCLUSION: There was little evidence for an association between salt intake estimated from spot urine and GA risk in our cross-sectional analysis of middle aged and older adults in Chile. Reverse causation bias cannot be ruled out and the sample size was limited to provide more precise estimates.
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Gastrite Atrófica , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Masculino , Pessoa de Meia-Idade , Humanos , Feminino , Idoso , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/etiologia , Cloreto de Sódio na Dieta/efeitos adversos , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/patologia , Estudos Transversais , Fatores de Risco , Gastrite Atrófica/complicações , Atrofia/complicaçõesRESUMO
Glucose variability (GV), which describes fluctuations in blood glucose levels within the day, is a phenomenon that is increasingly becoming the target of scientific attention when it comes to increased risk of coronary heart disease. Effects of GV may contribute to the development of metabolic syndrome and type 2 diabetes. Hyperglycemia can lead to oxidative stress resulting in molecular damage due to accumulation of reactive oxygen species (ROS). To discover more about the immediate effects of GV, continuous vs. bolus intravenous glucose administration was applied to 10 healthy men aged 21-30 years over a time frame of 48 h. Whole blood and plasma were analyzed for DNA damage using a comet assay with 3 different treatments (lysis buffer, H2O2, and the lesion-specific enzyme formamidopyrimidine DNA glycosylase (FPG)) as well as for the oxidative stress markers protein carbonyls (PC), unconjugated bilirubin (UCB), and ferric reducing antioxidant power (FRAP). A significant time effect was found in the three DNA damage treatments as well as in PC and UCB possibly due to circadian changes on oxidative stress, but no intervention group effect was observed for any of the markers. In conclusion, bolus vs. continuous glucose administration had no significant acute effect on DNA damage and markers of oxidative stress in healthy men.
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Diabetes Mellitus Tipo 2 , Glucose , Humanos , Masculino , Peróxido de Hidrogênio , Estresse Oxidativo , Dano ao DNA , Bilirrubina , Biomarcadores , VoluntáriosRESUMO
The continuous manufacturing (CM) of solid oral dosage forms has received increased attention in recent years and has become a leading technology in the pharmaceutical industry. A model has been developed based on process data from two design of experiments (DoEs), where the impact of the mixer process parameters, throughput (THR), hold up mass (HUM), impeller speed (IMP), and the input raw material bulk density (BDi), on the continuous process and the resulting drug product has been investigated. These statistical models revealed equations, describing process parameter interactions for optimization purposes. For the exit valve opening width (EV) at the bottom of the continuous mixer (CMT), the combination of high throughput (30 kg/h) and low impeller speed (300 rpm) resulted in optimal process conditions. Apparent bulk density of the blend (BD) within the process, fill depth (FD), and tensile strength (TS) were mainly impacted by input bulk density (BDi) of the tableting mixture, emphasizing the role of material attributes on the continuous manufacturing process. The apparent bulk density itself was, other than from the input bulk density, equally dependent from THR and IMP in opposite deflections. However, process parameters (THR and IMP) revealed a minor impact on the apparent BD compared to the input bulk density. FD was impacted mainly by THR ahead of IMP and the TS by IMP and THR to a similar extend, in opposite deflections. A simplified linear model to estimate the input bulk density revealed satisfactory prediction quality when included in the derived statistical model equations.
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Indústria Farmacêutica , Modelos Estatísticos , Comprimidos , Modelos Lineares , Resistência à TraçãoRESUMO
Circulating bilirubin is associated with reduced serum cholesterol concentrations in humans and in hyperbilirubinaemic Gunn rats. However, mechanisms contributing to hypocholesterolaemia remain unknown. Therefore, this study aimed to investigate cholesterol synthesis, transport and excretion in mutant Gunn rats. Adult Gunn and control rats were assessed for daily faecal sterol excretion using metabolic cages, and water was supplemented with [1-13 C]-acetate to determine cholesterol synthesis. Bile was collected to measure biliary lipid secretion. Serum and liver were collected for biochemical analysis and for gene/protein expression using RT-qPCR and western blot, respectively. Additionally, serum was collected and analysed from juvenile rats. A significant interaction of sex, age and phenotype on circulating lipids was found with adult female Gunn rats reporting significantly lower cholesterol and phospholipids. Female Gunn rats also demonstrated elevated cholesterol synthesis, greater biliary lipid secretion and increased total faecal cholesterol and bile acid excretion. Furthermore, they possessed increased hepatic low-density lipoprotein (LDL) receptor and SREBP2 expression. In contrast, there were no changes to sterol metabolism in adult male Gunn rats. This is the first study to demonstrate elevated faecal sterol excretion in female hyperbilirubinaemic Gunn rats. Increased sterol excretion creates a negative intestinal sterol balance that is compensated for by increased cholesterol synthesis and LDL receptor expression. Therefore, reduced circulating cholesterol is potentially caused by increased hepatic uptake via the LDL receptor. Future studies are required to further evaluate the sexual dimorphism of this response and whether similar findings occur in females with benign unconjugated hyperbilirubinaemia (Gilbert's syndrome). KEY POINTS: Female adult hyperbilirubinaemic (Gunn) rats demonstrated lower circulating cholesterol, corroborating human studies that report a negative association between bilirubin and cholesterol concentrations. Furthermore, female Gunn rats had elevated sterol excretion creating a negative intestinal sterol balance that was compensated for by elevated cholesterol synthesis and increased hepatic low-density lipoprotein (LDL) receptor expression. Therefore, elevated LDL receptor expression potentially leads to reduced circulating cholesterol levels in female Gunn rats providing an explanation for the hypocholesterolaemia observed in humans with elevated bilirubin levels. This study also reports a novel interaction of sex with the hyperbilirubinaemic phenotype on sterol metabolism because changes were only reported in females and not in male Gunn rats. Future studies are required to further evaluate the sexual dimorphism of this response and whether similar findings occur in females with benign unconjugated hyperbilirubinaemia (Gilbert's syndrome).
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Doença de Gilbert , Hipercolesterolemia , Animais , Bilirrubina/metabolismo , Colesterol/metabolismo , Feminino , Doença de Gilbert/metabolismo , Hiperbilirrubinemia/metabolismo , Hipercolesterolemia/metabolismo , Lipoproteínas LDL/metabolismo , Fígado/metabolismo , Masculino , Ratos , Ratos Gunn , Receptores de LDL/genética , Receptores de LDL/metabolismo , Caracteres Sexuais , Esteróis/metabolismoRESUMO
Covering: August 1984 up to January 2022Worldwide, increasing morbidity and mortality due to antibiotic-resistant microbial infections has been observed. Therefore, better prevention and control of infectious diseases, as well as appropriate use of approved antibacterial drugs are crucial. There is also an urgent need for the continuous development and supply of novel antibiotics. Thus, identifying new antibiotics and their further development is once again a priority of natural product research. The antibiotic corallopyronin A was discovered in the 1980s in the culture broth of the Myxobacterium Corallococcus coralloides and serves, in the context of this review, as a show case for the development of a naturally occurring antibiotic compound. The review demonstrates how a hard to obtain, barely water soluble and unstable compound such as corallopyronin A can be developed making use of sophisticated production and formulation approaches. Corallopyronin A is a bacterial DNA-dependent RNA polymerase inhibitor with a new target site and one of the few representatives of this class currently in preclinical development. Efficacy against Gram-positive and Gram-negative pathogens, e.g., Chlamydia trachomatis, Orientia tsutsugamushi, Staphylococcus aureus, and Wolbachia has been demonstrated. Due to its highly effective in vivo depletion of Wolbachia, which are essential endobacteria of most filarial nematode species, and its robust macrofilaricidal efficacy, corallopyronin A was selected as a preclinical candidate for the treatment of human filarial infections. This review highlights the discovery and production optimization approaches for corallopyronin A, as well as, recent preclinical efficacy results demonstrating a robust macrofilaricidal effect of the anti-Wolbachia candidate, and the solid formulation strategy which enhances the stability as well as the bioavailability of corallopyronin A.
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Anti-Infecciosos , Produtos Biológicos , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Produtos Biológicos/farmacologia , Humanos , Lactonas , ÁguaRESUMO
BACKGROUND: Mildly elevated bilirubin, a by-product of hemoglobin breakdown, might mitigate cardiometabolic risk factors including adiposity, dyslipidemia, and high blood pressure (BP). We investigated the cross-sectional relationship between (total) bilirubin and baseline cardiometabolic risk factors in 467,519 UK Biobank study participants. METHODS: We used multivariable-adjusted linear regression to estimate associations between bilirubin levels and risk factors of cardiometabolic diseases including body mass index (BMI), waist and hip circumferences (WC, HC), waist-to-hip ratio (WHR), fat mass (FM), and trunk FM, and the blood lipids: apolipoprotein A-I (apoA-I), apolipoprotein B (apoB), apoB/apoA-I, lipoprotein (a), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), LDL/HDL, TC/HDL, triglycerides (TG). Log-transformed bilirubin was modelled with restricted cubic splines and predicted mean values with 99% confidence intervals (CI) for each risk marker were estimated, separately. Second, we applied principal component analysis (PCA) for dimension reduction to in turn six anthropometric traits (height, weight, BMI, WC, HC, and WHR) and all above lipids. Last, we estimated associations (99%CI) between bilirubin and three components of the metabolic syndrome, i.e. WC, TG, and BP using logistic regression. RESULTS: After multivariable adjustments, higher levels of bilirubin were inversely associated with indicators of general adiposity (BMI and FM) and of body fat distribution (WC, HC, WHR, and trunk FM) in both men and women. For example, women with mildly elevated bilirubin (95th percentile equal to 15.0 µmol/L), compared to women with low bilirubin (5th percentile equal to 4.5 µmol/L), had on average a 2.0 kg/m2 (99% CI 1.9-2.1) lower BMI. Inverse associations were also observed with dyslipidemia among men and women. For example, mildly elevated bilirubin among men (95th percentile equal to 19.4 µmol/L) compared to low levels of bilirubin (5th percentile equal to 5.5 µmol/L) were associated with approx. 0.55 mmol/L (99% CI 0.53-0.56) lower TG levels, with similar inverse associations among women. Multiple-trait analyses using PCA confirmed single-trait analyses. Men and women with mildly elevated bilirubin levels ≥ 17.1 µmol/L, compared to low-normal bilirubin < 10 µmol/L had 13% (99% CI 8%-18%) and 11% (99% CI 4%-17%) lower odds of exceeding systolic BP levels of ≥ 130 mm Hg, respectively. CONCLUSIONS: Higher levels of bilirubin were inversely associated with cardiometabolic risk factors including adiposity, dyslipidemia, and hypertension.
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Bilirrubina , Fatores de Risco Cardiometabólico , Dislipidemias , Hipertensão , Obesidade , Apolipoproteína A-I , Apolipoproteínas B , Bilirrubina/sangue , Índice de Massa Corporal , HDL-Colesterol , Estudos Transversais , Bases de Dados Factuais , Dislipidemias/diagnóstico , Dislipidemias/epidemiologia , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Lipídeos , Masculino , Obesidade/diagnóstico , Obesidade/epidemiologia , Triglicerídeos , Reino Unido/epidemiologiaRESUMO
Tobacco-specific nitrosamine (TSNA) formation occurred during aerosol generation from select commercial cig-a-like e-cigarette products. To understand the drivers behind the potential formation of TSNAs in electronic cigarette (e-cigarette) aerosols and e-liquids, model e-liquid systems were generated in the lab to demonstrate that nitrite can react with nicotine and minor alkaloids to form TSNAs in e-liquids. In the presence of nitrite and nicotine, TSNA levels in e-liquids increased over time and the process was accelerated by elevated temperature. Additionally, TSNAs formed during aerosol generation when nitrite was present in the corresponding e-liquids. The commercial e-cigarette products that showed higher levels and formation of TSNAs were observed to contain nitrite and minor alkaloid impurities in the corresponding e-liquids. This study provides valuable information about drivers for TSNA formation in e-liquids and e-cigarette aerosols that may be applied to the evaluation and quality assurance of e-cigarette products.
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Alcaloides , Sistemas Eletrônicos de Liberação de Nicotina , Nitrosaminas , Aerossóis , Nicotina , Nitritos , NicotianaRESUMO
PURPOSE: Cardiovascular diseases and cognitive decline, predominant in ageing populations, share common features of dysregulated one-carbon (1C) and cardiometabolic homeostasis. However, few studies have addressed the impact of multifaceted lifestyle interventions in older adults that combine both nutritional supplementation and resistance training on the co-regulation of 1C metabolites and cardiometabolic markers. METHODS: 95 institutionalised older adults (83 ± 6 years, 88.4% female) were randomised to receive resistance training with or without nutritional supplementation (Fortifit), or cognitive training (control for socialisation) for 6 months. Fasting plasma 1C metabolite concentrations, analysed by liquid chromatography coupled with mass spectrometry, and cardiometabolic parameters were measured at baseline and the 3- and 6-month follow-ups. RESULTS: Regardless of the intervention group, choline was elevated after 3 months, while cysteine and methionine remained elevated after 6 months (mixed model time effects, p < 0.05). Elevated dimethylglycine and lower betaine concentrations were correlated with an unfavourable cardiometabolic profile at baseline (spearman correlations, p < 0.05). However, increasing choline and dimethylglycine concentrations were associated with improvements in lipid metabolism in those receiving supplementation (regression model interaction, p < 0.05). CONCLUSION: Choline metabolites, including choline, betaine and dimethylglycine, were central to the co-regulation of 1C metabolism and cardiometabolic health in older adults. Metabolites that indicate upregulated betaine-dependent homocysteine remethylation were elevated in those with the greatest cardiometabolic risk at baseline, but associated with improvements in lipid parameters following resistance training with nutritional supplementation. The relevance of how 1C metabolite status might be optimised to protect against cardiometabolic dysregulation requires further attention.
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Carbono , Doenças Cardiovasculares , Idoso , Envelhecimento , Betaína , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Colina , Suplementos Nutricionais , Feminino , Homocisteína , Humanos , MasculinoRESUMO
Although the androgen receptor (AR) is a validated target for the treatment of prostate cancer, resistance to antiandrogens necessitates the development of new therapeutic modalities. Exploiting the ubiquitin-proteasome system with proteolysis-targeting chimeras (PROTACs) has become a practical approach to degrade specific proteins and thus to extend the portfolio of small molecules used for the treatment of a broader spectrum of diseases. Herein, we present three subgroups of enzalutamide-based PROTACs in which only the exit vector was modified. By recruiting cereblon, we were able to demonstrate the potent degradation of AR in lung cancer cells. Furthermore, the initial evaluation enabled the design of an optimized PROTAC with a rigid linker that degraded AR with a DC50 value in the nanomolar range. These results provide novel AR-directed PROTACs and a clear rationale for further investigating AR involvement in lung cancer models.
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Neoplasias Pulmonares , Neoplasias da Próstata , Receptores Androgênicos , Humanos , Masculino , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Proteólise , Receptores Androgênicos/metabolismo , Relação Estrutura-Atividade , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismoRESUMO
Process simulation facilitates scale-up of hot-melt extrusion (HME) and enhances proper understanding of the underlying critical process parameters. However, performing numeric simulations requires profound knowledge of the employed materials' properties. For example, an accurate description of the compounds' melt rheology is paramount for proper simulations. Hence, sample preparation needs to be optimized to yield results as predictive as possible. To identify the optimal preparation method for small amplitude oscillatory shear (SAOS) rheological measurements, binary mixtures of hydroxypropylmethylcellulose acetate succinate or methacrylic acid ethyl acrylate copolymer (Eudragit L100-55) together with the model drugs celecoxib and ketoconazole were prepared. The physical powder mixtures were introduced into the SAOS as a compressed tablet or a disk prepared via vacuum compression molding (VCM). Simulations with the derived parameters were conducted and compared to lab-scale extrusion trials. VCM was identified as the ideal preparation method resulting in the highest similarity between simulated and experimental values, while simulation based on conventional powder-based methods insufficiently described the HME process.
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Transtorno do Espectro Autista , Tecnologia de Extrusão por Fusão a Quente , Composição de Medicamentos/métodos , Temperatura Alta , Humanos , Pós , Solubilidade , ComprimidosRESUMO
Starting point of the presented study were abrasion effects occurring during a twin screw wet granulation (TSG) process of a new chemical entity (NCE) formulation, resulting in gray spots on the final tablets. Several actions and systematic changes of equipment and process parameter settings of TSG process were conducted which reduced the visual defect rate of the tablets, i.e., gray spots on the surface, below the specification limit. To understand the rationale and mechanism behind these improvements, correlations of defect rates and wall friction measurements using a Schulze ring shear tester were evaluated. To check the suitability of the method, a broad range of wall materials as well as powder formulations at various moisture levels were investigated with regard to their wall friction angle. As differences in wall friction angle could be detected, further experiments were conducted using wall material samples made out of different screw materials for TSG. Evaluation of these screw wall material samples gave first hints, which screw materials should be preferred in regard of friction for TSG process. In the finally presented case study, wall friction measurements were performed using the above mentioned NCE formulation with known abrasion issues at TSG processing. The results confirmed that changes which led to a reduced visual defect rate of tablets correlated with a decreased wall friction angle. The results suggest wall friction measurements as a potent tool for equipment selection and establishment of a suitable process window prior to conducting TSG experiments.
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Excipientes , Tecnologia Farmacêutica , Composição de Medicamentos , Fricção , Tamanho da Partícula , ComprimidosRESUMO
The present study explored vacuum drum drying (VDD) as potential drying technique for the solidification of crystalline ritonavir nanosuspensions prepared by wet-ball milling. In detail, the impact of drying protectants (mannitol, lactose, trehalose) added to the ritonavir nanosuspension was assessed in dependence of the drum temperature with respect to processibility via VDD, resulting intermediate powder properties, remaining nanoparticulate redispersibility and crystallinity. A clear impact of the glass transition temperature (Tg) of the drying protectant on the redispersibility/crystallinity of the VDD intermediate was observed. Increased Tg of the drying protectant was associated with improved redispersibility/crystallinity at a defined drum temperature. Consequently, the high Tg-substance trehalose and lactose showed a better performance than mannitol at higher drum temperatures. However, the processability and related powder properties were not in accordance with this observation. Mannitol containing formulations showed superior processibility to those containing trehalose/lactose. Moreover, the impact of the tableting and encapsulation process on the redispersibility of the VDD intermediate was studied for a selected formulation. Neither process demonstrated a negative impact on redispersibility. In conclusion, vacuum drum drying is a promising drying technique for the solidification of nanosuspensions to result in dried powder still containing ritonavir nanoparticles while demonstrating acceptable to good downstream processibility to tablets/capsules.
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Nanopartículas , Ritonavir , Liofilização/métodos , Lactose , Manitol , Nanopartículas/química , Tamanho da Partícula , Pós , Suspensões , Trealose , VácuoRESUMO
Advanced glycation endproducts (AGEs) may contribute to liver carcinogenesis because of their proinflammatory and prooxidative properties. Diet is a major source of AGEs, but there is sparse human evidence on the role of AGEs intake in liver cancer etiology. We examined the association between dietary AGEs and the risk of hepatobiliary cancers in the European Prospective Investigation into Cancer and Nutrition prospective cohort (n = 450 111). Dietary intake of three AGEs, Nε -[carboxymethyl]lysine (CML), Nε -[1-carboxyethyl]lysine (CEL) and Nδ -[5-hydro-5-methyl-4-imidazolon-2-yl]-ornithine (MG-H1), was estimated using country-specific dietary questionnaires linked to an AGEs database. Cause-specific hazard ratios (HR) and their 95% confidence intervals (CI) for associations between dietary AGEs and risk of hepatocellular carcinoma (HCC), gallbladder and biliary tract cancers were estimated using multivariable Cox proportional hazard regression. After a median follow-up time of 14.9 years, 255 cases of HCC, 100 cases of gallbladder cancer and 173 biliary tract cancers were ascertained. Higher intakes of dietary AGEs were inversely associated with the risk of HCC (per 1 SD increment, HR-CML = 0.87, 95% CI: 0.76-0.99, HR-CEL = 0.84, 95% CI: 0.74-0.96 and HR-MH-G1 = 0.84, 95% CI: 0.74-0.97). In contrast, positive associations were observed with risk of gallbladder cancer (per 1 SD, HR-CML = 1.28, 95% CI: 1.05-1.56, HR-CEL = 1.17; 95% CI: 0.96-1.40, HR-MH-G1 = 1.27, 95% CI: 1.06-1.54). No associations were observed for cancers of the intra and extrahepatic bile ducts. Our findings suggest that higher intakes of dietary AGEs are inversely associated with the risk of HCC and positively associated with the risk of gallbladder cancer.
RESUMO
Selection of an appropriate formulation to stabilize therapeutic proteins against aggregation is one of the most challenging tasks in early-stage drug product development. The amount of aggregates is more difficult to quantify in the case of peptides due to their small molecular size. Here, we investigated the suitability of diffusion self-interaction parameters (kD) and osmotic second virial coefficients (B22) for high-throughput (HT) screening of peptide formulations regarding their aggregation risk. These parameters were compared to the effect of thermal stress on colloidal stability. The formulation matrix comprised six buffering systems at two selected pH values, four tonicity agents, and a common preservative. The results revealed that electrostatic interactions are the main driver to control colloidal stability. Preferred formulations consisted of acetate and succinate buffer at pH 4.5 combined with glycerol or mannitol and optional m-cresol. kD proved to be a suitable surrogate for B22 as an indicator of high colloidal stability in the case of peptides as was previously described for globular proteins and antibodies. Formulation assessment solely based on kD obtained by HT methods offers important insights into the optimization of colloidal stability during the early development of peptide-based liquid formulations and can be performed with a limited amount of peptide (â¼360 mg).
Assuntos
Coloides/química , Desenvolvimento de Medicamentos/métodos , Ensaios de Triagem em Larga Escala/métodos , Peptídeos/química , Coloides/uso terapêutico , Difusão Dinâmica da Luz , Concentração de Íons de Hidrogênio , Peptídeos/uso terapêutico , Agregados Proteicos , Estabilidade ProteicaRESUMO
Indomethacin (IND) is one of the supporting drug candidates for colonic targeting but it belongs to BCS class II category presenting a challenge in optimal targeting at the colonic site. To overcome this challenge, we sought to prepare a pH-dependent soluble ternary solid dispersion (SD) of IND of improved solubility and dissolution rate at the colon without the need for a coating. The current study focuses on the preparation of binary SDs of API (IND) with shellac (SSB 55) and Eudragit FS 100 (EFS) and ternary mixtures of IND, SSB 55 together with a new grade of HPMC (A15). Respective SDs were prepared via HME to achieve gastric protection and improved dissolution performance including maintenance of supersaturation. The SDs were characterized and tested for in-vitro dissolution performance using a pH shift dissolution method from 1.1, 5.5, 6.8, and 7.4. A ternary extrudate of IND, SSB 55, and A15 showed improved protection below pH 5.5 with a complete release of 99.5% at pH 7.4 compared to IND neat and binary extrudates from IND-A15, IND-SSB 55, and IND-EFS. It was attributed to an increased level of intermolecular interaction confirmed by ATR-IR and was studied for stability. It was found that in a ternary mixture containing IND, A15 and SSB 55 an increased hydrogen bonding interaction is present, which resulted in improved dissolution performance compared to binary mixtures. Therefore, ternary SDs proved to be a promising concept for future development of colon targeting of poorly soluble drugs.