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1.
Proc Natl Acad Sci U S A ; 121(28): e2314320121, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38954540

ABSTRACT

Liquid-phase electron microscopy (LP-EM) imaging has revolutionized our understanding of nanosynthesis and assembly. However, the current closed geometry limits its application for open systems. The ubiquitous physical process of the coffee-ring phenomenon that underpins materials and engineering science remains elusive at the nanoscale due to the lack of experimental tools. We introduce a quartz nanopipette liquid cell with a tunable dimension that requires only standard microscopes. Depending on the imaging condition, the open geometry of the nanopipette allows the imaging of evaporation-induced pattern formation, but it can also function as an ordinary closed-geometry liquid cell where evaporation is negligible despite the nano opening. The nano coffee-ring phenomenon was observed by tracking individual nanoparticles in an evaporating nanodroplet created from a thin liquid film by interfacial instability. Nanoflows drive the assembly and disruption of a ring pattern with the absence of particle-particle correlations. With surface effects, nanoflows override thermal fluctuations at tens of nanometers, in which nanoparticles displayed a "drunken man trajectory" and performed work at a value much smaller than kBT.

3.
Food Chem ; 458: 140236, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38959805

ABSTRACT

Coffee, a globally consumed beverage, has raised concerns in Islamic jurisprudence due to the possible presence of alcohol compounds. This research aims to utilise the sensitivity and reliability of 1H NMR spectroscopy in the quantification of alcohol compounds such as ethanol, furfuryl alcohol, and 5-(hydroxymethyl) furfural (HMF) in commercial instant coffee. Analysis of seven products was performed using advanced 1H Nuclear Magnetic Resonance (NMR) spectroscopy together with Statistical Total Correlation Spectroscopy (STOCSY) and Resolution-Enhanced (RED)-STORM. The analysis of the 100 mg sample revealed the absence of ethanol. The amount of furfuryl alcohol and HMF in the selected commercial instant coffee samples was 0.817 µg and 0.0553 µg, respectively. This study demonstrates the utility of 1H NMR spectroscopy in accurate quantification of trace components for various applications.

4.
J Environ Manage ; 366: 121682, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38991333

ABSTRACT

In this research, spent coffee grounds (SCG) are converted into a highly valuable porous adsorbent which removes chromium (VI) from wastewater with high efficiency. A set of nine Spent Coffee Ground Activated Carbon (SCG-AC) adsorbent samples were synthesized, by varying key parameters including pyrolysis temperature (400, 600 °C), pyrolysis duration (1 and 2 h), and the impregnation ratio of the activating agent, KOH (ranging from 0:1 to 2:1). Characterizations of these adsorbent samples were conducted by advanced analytical tools including SEM, EDX, XRD, FTIR, TGA, and BET. Furthermore, we carried out adsorption studies, exploring the effects of temperature and dosage variations. Additionally, point zero charge experiments and desorption studies were carried out to further understand the adsorption process. The outcomes of our investigation demonstrate the successful synthesis of these spent coffee ground-derived adsorbents, with a yield of up to 34%. Notably, these adsorbents exhibited high efficiency in extracting chromium (VI) from water, with removal efficiencies ranging from 75% to 100%. The adsorption isotherms revealed the Langmuir model to be the most fitting descriptor of the adsorption behavior. Moreover, a thermodynamics study revealed the process to be endothermic in nature which furthers our understanding of the underlying mechanisms. Importantly, our cost assessment shows the economic advantage of the synthesized adsorbent over commercial counterparts such as zeolite, making it a competitive choice for real-world applications. In summation, the study not only introduces an innovative and sustainable utilization of spent coffee grounds but also delivers an in-depth exploration of the synthesized adsorbent's ability in chromium (VI) removal. Our holistic approach, encompassing thorough experimentation, characterization, and economic evaluation, solidifies the significance of this research in tackling environmental concerns and propelling advancements in wastewater treatment methodologies.

5.
Endocrinol Diabetes Nutr (Engl Ed) ; 71(6): 236-245, 2024.
Article in English | MEDLINE | ID: mdl-38986627

ABSTRACT

INTRODUCTION: Coffee consumption has demonstrated an effect on the regulation of appetite, causing less hunger and/or greater satiety; however, its effects are not well known in woman with overweight or obesity. Therefore, this study aimed to evaluate the effect of coffee consumption on hunger, satiety, sensory specific desire (SSD), and dietary intake in women with overweight or obesity. METHODOLOGY: A randomized crossover clinical trial was realized in 3 sessions: in the first session a clinical history, anthropometric measurements and body composition analysis were performed; in sessions 2 and 3 the participants randomly consumed 240mL of coffee with 6mg/caffeine/kg of weight or 240mL of water along with a standardized breakfast. At fasting and every 30min after breakfast for the next 3h, appetite sensations and SSD were recorded using visual analog scales. Blood samples were taken at fasting, 30 and 180min after breakfast. Dietary intake was recorded in the rest of the intervention days. RESULTS: In the coffee intervention there was an increased desire for sweet foods, higher fructose intake during the rest of the day, and higher triglyceride levels than with the water intervention. No differences were detected in ghrelin or cholecystokinin. CONCLUSIONS: Coffee consumption may lead to higher triglycerides and higher intake of simple sugars, mainly fructose, through changes in the SSD. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/NCT05774119.


Subject(s)
Appetite , Coffee , Cross-Over Studies , Obesity , Overweight , Humans , Female , Adult , Pilot Projects , Appetite/drug effects , Hunger/drug effects , Satiation/drug effects , Triglycerides/blood , Middle Aged , Ghrelin/blood
6.
Geroscience ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38963648

ABSTRACT

This review provides a comprehensive synthesis of longitudinal observational and interventional studies on the cardiometabolic effects of coffee consumption. It explores biological mechanisms, and clinical and policy implications, and highlights gaps in the evidence while suggesting future research directions. It also reviews evidence on the causal relationships between coffee consumption and cardiometabolic outcomes from Mendelian randomization (MR) studies. Findings indicate that while coffee may cause short-term increases in blood pressure, it does not contribute to long-term hypertension risk. There is limited evidence indicating that coffee intake might reduce the risk of metabolic syndrome and non-alcoholic fatty liver disease. Furthermore, coffee consumption is consistently linked with reduced risks of type 2 diabetes (T2D) and chronic kidney disease (CKD), showing dose-response relationships. The relationship between coffee and cardiovascular disease is complex, showing potential stroke prevention benefits but ambiguous effects on coronary heart disease. Moderate coffee consumption, typically ranging from 1 to 5 cups per day, is linked to a reduced risk of heart failure, while its impact on atrial fibrillation remains inconclusive. Furthermore, coffee consumption is associated with a lower risk of all-cause mortality, following a U-shaped pattern, with the largest risk reduction observed at moderate consumption levels. Except for T2D and CKD, MR studies do not robustly support a causal link between coffee consumption and adverse cardiometabolic outcomes. The potential beneficial effects of coffee on cardiometabolic health are consistent across age, sex, geographical regions, and coffee subtypes and are multi-dimensional, involving antioxidative, anti-inflammatory, lipid-modulating, insulin-sensitizing, and thermogenic effects. Based on its beneficial effects on cardiometabolic health and fundamental biological processes involved in aging, moderate coffee consumption has the potential to contribute to extending the healthspan and increasing longevity. The findings underscore the need for future research to understand the underlying mechanisms and refine health recommendations regarding coffee consumption.

7.
J Acad Nutr Diet ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38971221

ABSTRACT

BACKGROUND: Higher coffee intake has been associated with reduced risk of prostate cancer, particularly aggressive forms. The activation of the PI3K signaling pathway plays an important role in prostate carcinogenesis. OBJECTIVE: To evaluate associations between pre-diagnostic coffee intake and a PI3K activation score, the expression/presence of PI3K regulators, and downstream effectors in tumor tissue from men with prostate cancer in the Health Professionals Follow-up Study, a prospective cohort study conducted in the US. DESIGN: A case-only study design was applied. Coffee intake was assessed using validated food frequency questionnaires completed in 1986 and every four years thereafter until prostate cancer diagnosis. PARTICIPANTS/SETTING: Study participants comprised 1,242 men diagnosed with prostate cancer from 1986 to 2009 and with tumor markers assessed from tissue microarrays constructed from tumor specimens. MAIN OUTCOME MEASURES: The outcomes include the PI3K activation score; expression of insulin receptor and IGF1 receptor; angiogenesis markers; and presence of the tumor suppressor PTEN, chronic and acute inflammation, simple atrophy, and post-atrophic hyperplasia. STATISTICAL ANALYSES PERFORMED: Multivariable linear or logistic regression was conducted to estimate associations between coffee intake and tumor marker expression/presence. RESULTS: Among coffee drinkers (86.6% of the population), median (25th-75th) coffee intake was 2 (1-3) cups/day. The associations between coffee consumption and the tumor markers of interest were generally weak with modest precision. When comparing men who drank >3 cups/day of coffee with nondrinkers, the absolute percent difference in the PI3K activation score and angiogenesis markers ranged from 0.6% to 3.6%. The odds ratios for PTEN loss, IGF1 receptor and insulin receptor expression, and presence of chronic and acute inflammation, simple atrophy, and post-atrophic hyperplasia also were not statistically significant, were imprecise, and ranged from 0.82 to 1.58. CONCLUSIONS: Coffee intake was not observed to be associated with PI3K activation, related regulators, and several effectors in prostate tumor tissue. Studies exploring alternative pathways or earlier steps in carcinogenesis are needed to investigate the underlying mechanisms of the coffee and prostate cancer association.

9.
J Bone Miner Metab ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38985180

ABSTRACT

INTRODUCTION: Despite a large number of observational studies examining the effect of coffee consumption(CC) on bone disorders(BDs), particularly, osteoarthritis(OA), osteoportic fracture(OF), and rheumatoid arthritis(RA), the conclusions are highly controversial. Thus, it is essential to examine the causal association between CC and BDs. MATERIALS AND METHODS: Mendelian randomization (MR) analysis was performed to assess the causal influence of CC on OF, RA, and OA. The main endpoint was the odds ratio (OR) of the inverse variance weighted (IVW) approach. In addition, the weighted median (WM), MR-Egger regressions, MR-pleiotropy residual sum and outlier (MR-PRESSO) and multivariable MR (MVMR) were included in sensitivity analyses. Furthermore, the function of causal SNPs was evaluated by gene ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and protein-protein interaction networks. RESULTS: Primary MR analysis based on the IVW method suggested that changes in CC alter risk of OF (OR = 1.383, 95%CI 1.079-1.853, P = 0.039), RA(OR: 1.623, 95%CI 1.042-2.527, P = 0.032) and HOA (hip osteoarthritis, OR = 1.536, 95% CI 1.044-2.259, P = 0.021). However, these causal relationships were not robust in sensitivity analyses. In contrast, there is a positive causal relationship between increased CC and the risk of KOA (knee osteoarthritis, OR: 2.094, 95%CI: 1.592-2.754, P = 1.41 × 10-7), as evidenced by the IVW using random effect. A similar effect size was observed across all MR sensitivity analyses, with no evidence of horizontal pleiotropy. CONCLUSION: Based on our MR analysis, increased CC was causally linked to an increase in the risk of KOA. Genetic predictions suggested that CC reduction may have benefits for bone health.

10.
Int J Biol Macromol ; 275(Pt 2): 133740, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38986986

ABSTRACT

Coffee beverage is a source of dietary fiber composed by arabinogalactans, which can also be associated to proteins and phenolic compounds, originating melanoidins. Human colonic in vitro fermentations of coffee fractions, one rich in melanoidins (Mel) and the other in its parental polysaccharide arabinogalactans (AG), were performed in order to evaluate the metabolites produced by microbiota, namely short-chain fatty acids (SCFA), phenolic compounds, and bile acids. After 48 h of fermentation, a higher fermentability of the carbohydrate fraction of AG (62 %) than that of Mel (27 %) was observed, resulting in a SCFA content of 63 mM and 22 mM, respectively. Supplementation with AG and Mel fractions decreased the acetate:propionate ratio from 4.7 (in the absence of coffee fractions) to 2.5 and 3.5, respectively, suggesting a potential inhibition of HMG-CoA reductase, a rate-limiting enzyme for cholesterol synthesis. The fermentation of coffee fractions yielded dihydroferulic and dihydrocaffeic acids, known to have antioxidant properties. In the presence of Mel, it was observed a decrease (from 0.25 to 0.16 mg/mL) in the production of secondary bile acids, whose high content is associated to the development of several diseases, such as colorectal cancer, neurodegenerative and cardiovascular.

11.
Molecules ; 29(13)2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38999011

ABSTRACT

Coffee pulp wines were produced through the mixed fermentation of Saccharomyces cerevisiae, and the flavor and sensory characteristics were comparatively evaluated. A total of 87 volatile components were identified from five coffee pulp wines, of which 68 were present in all samples, accounting for over 99% of the total concentration. The sample fermented contained significantly higher levels of volatile metabolites (56.80 mg/g). Alcohols (22 species) and esters (26 species) were the main flavor components, with the contents accounting for 56.45 ± 3.93% and 31.18 ± 4.24%, respectively, of the total. Furthermore, 14 characteristic components were identified as potential odor-active compounds, contributing to sweet and floral apple brandy flavor. Although the characteristic components are similar, the difference in the content makes the overall sensory evaluation of the samples different. The samples formed by fermentation of four strains, which obtained the highest score (86.46 ± 0.36) in sensory evaluation, were further interpreted and demonstrated through the Mantel test. The results of the component analysis were effectively distinguished by OPLS-DA and PCA, and this validation was supported by sensory evaluation. The research results provided a technical reference for the production of coffee pulp wines.


Subject(s)
Coffee , Fermentation , Taste , Volatile Organic Compounds , Wine , Wine/analysis , Coffee/chemistry , Volatile Organic Compounds/analysis , Flavoring Agents/analysis , Odorants/analysis , Saccharomyces cerevisiae/metabolism , Humans
12.
Plants (Basel) ; 13(13)2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38999694

ABSTRACT

The maturation of Arabica coffee fruits is influenced by both endogenous and external factors. The stage of fruit maturation affects the chemical composition of the beans, which in turn impacts the quality of the coffee beverage. During maturation, the fruit peel changes colour from green to red (cherry), signalling the optimal harvest time and suggesting high fruit quality. However, the degree of redness can vary, indicating different levels of maturity. This study aimed to explore the variation in soluble sugar accumulation in relation to the redness of coffee fruit tissues. We classified ripe fruits into six ripeness categories based on the intensity of the red colour of the epicarp, measured using a colourimeter. We analysed total soluble sugar, sucrose, and starch in three parts: coat (exocarp + mesocarp), coat juice (obtained by squeezing the coat), and beans. Our findings reveal that the variation in sugar in the endosperm does not correspond to changes in the coat, suggesting separate regulation of sugar accumulation, particularly sucrose, which is crucial for coffee quality. Our data indicate that there is no transfer of sucrose and reducing sugars from the red coat to the bean.

13.
Plants (Basel) ; 13(13)2024 Jul 07.
Article in English | MEDLINE | ID: mdl-38999716

ABSTRACT

Genome-wide association studies (GWASs) allow for inferences about the relationships between genomic variants and phenotypic traits in natural or breeding populations. However, few have used this methodology in Coffea arabica. We aimed to identify chromosomal regions with significant associations between SNP markers and agronomic traits in C. arabica. We used a coffee panel consisting of 195 plants derived from 13 families in F2 generations and backcrosses of crosses between leaf rust-susceptible and -resistant genotypes. The plants were phenotyped for 18 agronomic markers and genotyped for 21,211 SNP markers. A GWAS enabled the identification of 110 SNPs with significant associations (p < 0.05) for several agronomic traits in C. arabica: plant height, plagiotropic branch length, number of vegetative nodes, canopy diameter, fruit size, cercosporiosis incidence, and rust incidence. The effects of each SNP marker associated with the traits were analyzed, such that they can be used for molecular marker-assisted selection. For the first time, a GWAS was used for these important agronomic traits in C. arabica, enabling applications in accelerated coffee breeding through marker-assisted selection and ensuring greater efficiency and time reduction. Furthermore, our findings provide preliminary knowledge to further confirm the genomic loci and potential candidate genes contributing to various structural and disease-related traits of C. arabica.

14.
Nutrients ; 16(13)2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38999772

ABSTRACT

Coffee consumption is globally widespread and has become a lifestyle habit. This study investigated coffee consumption and liver-related survival in a large cohort of 455,870 individuals with UK biobank, categorized into without steatosis, metabolic dysfunction-associated steatotic liver disease (MASLD), and MASLD and increased alcohol intake (MetALD). Inverse probability of treatment weighting (IPTW) adjusted for confounding variables was used, followed by Kaplan-Meier analysis. Moderate coffee consumption (1-2 cups per day) was associated with lower all-cause mortality across the entire cohort, without the steatosis, MASLD (p < 0.0001), and MetALD cohorts (p = 0.0047 for pre-IPTW, p = 0.027 for post-IPTW). Before IPTW adjustment, consuming one or more cups of coffee per day appeared to significantly reduce liver-related mortality in the overall (p = 0.015) and MASLD cohorts (p = 0.011). However, post-IPTW application, no significant differences in liver-related mortality were observed between the coffee intake groups (p = 0.778, 0.319, 0.564, 0.238 for each group). While increased coffee consumption initially seemed to reduce liver-related mortality, after IPTW adjustment, only all-cause mortality significantly decreased (p < 0.0001 and p = 0.027). These findings suggest that previous studies might have overestimated the favorable effect of coffee intake on chronic liver disease due to confounding factors.


Subject(s)
Coffee , Humans , Female , Male , Middle Aged , Cohort Studies , Aged , Liver Diseases/mortality , Adult , United Kingdom/epidemiology , Risk Factors , Kaplan-Meier Estimate
15.
J Agric Food Chem ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38984670

ABSTRACT

Coffee is a widely consumed beverage rich in bioactive phytochemicals. This study investigated the effect of brewing method on the profile of potential bioactive compounds in different coffee beverages using metabolomics and lipidomics based on UHPLC-MS/QTOF. The oil contents of the espresso coffee (EC), pot coffee (PC), instant coffee (IC), and filter coffee (FC) beverages studied were 0.13% ± 0.002, 0.12% ± 0.001, 0.04% ± 0.002, and 0.03% ± 0.003, respectively. Univariate analysis indicated significant differences (P < 0.001) in oil content when EC and PC beverages were compared with IC and FC beverages. Principal component analysis revealed similarities in the lipid profiles of FC and EC beverages and the hydrophilic profiles of PC and FC beverages. The EC beverage had the highest intensity of hydrophilic compounds such as adenine, theobromine, chlorogenic acid, and caffeine. The PC beverage was the most abundant in triglycerides, phosphatidylcholine, and diterpenes. Cafestol and kahweol esters, but not their free forms, were the most abundant diterpenes in the PC beverage. This work provides information on the differences in the profile of potentially bioactive compounds in four commonly consumed coffee beverage types and, thus, on the possible differences in the health effects of these coffee beverage types.

16.
Curr Res Food Sci ; 9: 100788, 2024.
Article in English | MEDLINE | ID: mdl-39005496

ABSTRACT

Currently, coffee fermentation is visually operated, which results in incomplete or excessive processes and coffees with undesirable characteristics. In front of it, pH and total soluble solids (TSS) have been shown to be good fermentation indicators, although this requires rapid, accurate, and chemical-free measurement techniques such as NIR spectroscopy. However, the complexity of the NIR spectra requires optimization steps in which variable selection techniques simplify profiles and subsequent models. This work tests a new covering array feature selection (CAFS) approach on NIR spectra to optimize prediction models in coffee samples during fermentation. Spectral profiles in the range 1100-2100 nm were extracted from coffee beans (Typica, Caturra, and Catimor varieties) raw and during fermentation (4, 8, 12, 16, 20, and 24 h). Partial least-squares regressions (PLSR) were performed using full spectra using a five-fold cross-validation strategy for training and validation. The relevant wavelengths were then selected using the ß coefficients, the important projection of variables (VIP), and the CAFS method. Finally, optimized models were performed using the relevant wavelengths and compared among these using their statistical metrics. The models performed using the selected variables (22-47) of CAFS showed the best performance in predicting pH (R 2 = 0.825-0.903, RMSE = 0.096-0.158, RPD = 6.33-10.38) and TSS (R 2 = 0.865-0.922, RMSE = 0.688-1.059, RPD = 0.94-1.45) compared to the other methods. These findings suggest that simple and efficient models could be performed and implemented in routine analysis due to the maximum coverage and minimum cardinality of CAFS.

17.
J Cancer ; 15(14): 4551-4565, 2024.
Article in English | MEDLINE | ID: mdl-39006079

ABSTRACT

Objectives: The unresolved issue of the relationship between sex differences in tea, coffee, and beverage consumption and malignancy risk prompted our study in 2022. Methods: Logistic proportional hazards models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) in our investigation of the associations between cancer risk and tea, coffee, and beverage consumption. Results: Our findings revealed that frequent consumption of white tea significantly reduced the occurrence of malignant tumours, but this effect was detected only in the fully adjusted model for males (OR: 0.736, 95% CI: 0.095-5.704). The amount of sugar added to coffee was associated with an increased risk of malignancy in a dose-dependent manner (P for trend = 0.001), with significance observed for both men (P for trend = 0.049) and women (P for trend = 0.005) in the final model. Notably, individuals who consumed more than 2100 ml of sugary beverages daily had a statistically significant reduction in malignancy risk (OR: 0.219, 95% CI: 0.052-0.917). Interestingly, the intake of sugary beverages had a protective effect on cancer incidence, with a significant effect on males (P for trend = 0.031) but not females (P for trend = 0.096) in the final model. Conclusions: Our study highlights the substantial impact of regular white tea consumption on reducing the risk of malignant tumours in males. This study first reported that the potential protective effect of consuming sugary beverages is predominantly observed in males, and a correlation between the amount of sugar added to coffee and a heightened risk of malignancy.

18.
Food Chem X ; 23: 101556, 2024 Oct 30.
Article in English | MEDLINE | ID: mdl-39007118

ABSTRACT

This study aimed to identify the key volatile compounds in two types of processed arabica coffee husk tea, elucidate their olfactory characteristics, and investigate their antioxidant and anti-inflammatory activities. Sensory evaluation indicated differences between the two groups. A total of 64 and 99 compounds were identified in the C and FC groups, respectively, with 5 identified as key aroma compounds (ROAV≥1). Molecular simulations indicated that four common key aroma compounds were successfully docked with OR1A1 and OR5M3 receptors, forming stable complexes. Furthermore, 14 volatile compounds interacted with 140 targets associated with oxidation and inflammation, linking to 919 gene ontology (GO) terms and 135 kyoto encyclopedia of genes and genomes (KEGG) pathways. Molecular simulations revealed that these volatile components showed antioxidant and anti-inflammatory effects by interacting with core receptors through several forces, including van der Waals, Pi-alkyl, and Pi-cation interactions and hydrogen bonds.

19.
Res Q Exerc Sport ; : 1-9, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39008947

ABSTRACT

The aim of this study was to investigate the effects of caffeine on heart rate and heart rate variability (HRV) at rest and during submaximal exercise. Using a balanced, double-blind, randomized, crossover design, 16 male cyclists (age: 37 ± 9 years; V˙O2max: 4.44 ± 0.67 L·min-1) completed three trials in an air-conditioned laboratory. In Trial 1, cyclists completed two incremental cycling tests to establish the V˙O2-power output relationship and V˙O2max. In trials 2 and 3, cyclists were evaluated for heart rate and HRV at rest, after which they ingested a capsule containing 5 mg·kg-1 of caffeine or placebo. Thirty-five minutes post-supplementation, additional resting heart rate and HRV readings were taken after which cyclists completed a submaximal incremental cycling test (6 min stages) at 40-80% of V˙O2max; with HR and HRV measurements taken in the last 5 min of each increment. HRV was determined from the root mean square of successive differences between R-R intervals. There were significant supplement × exercise intensity interactions on heart rate (p = .019) and HRV (p = .023), with post hoc tests on the latter showing that caffeine increased HRV at 40%, 50%, and 60% of V˙O2max by 3.6 ± 4.9, 2.6 ± 2.8, and 0.6 ± 1.7 ms, respectively. There was a supplement × time interaction effect on resting HRV (p < .001), but not on heart rate (p = .351). The results of this study support the suggestion that caffeine increases the parasympathetic modulation of heart rate.Clinical trial registration number: NCT05521386.

20.
Biol Reprod ; 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39012043

ABSTRACT

Preeclampsia (PE) is a pregnancy-specific disease that causes maternal symptoms such as high blood pressure and adverse pregnancy outcomes. 2-methoxyestradiol (2-MeO-E2), an endogenous metabolite of 17ß-estradiol (E2) formed by Catechol-O-Methyltransferase (COMT), plays an important role in pregnancy. Our earlier studies have shown that polyphenols present in coffee can inhibit COMT activity, which may inhibit the formation of 2-MeO-E2 and contribute to PE. Therefore, the current study aims to investigate the possible effect and mechanism of coffee intake during pregnancy on PE in SD rats. Coffee is administered with or without cotreatment of 2-MeO-E2 to pregnant rats from the10th to the18th day of pregnancy. The results show that pregnant rats with coffee intake had prominent fetal growth restriction, hypertension and proteinuria, which can be ameliorated by co-treatment of 2-MeO-E2. In addition, coffee treatment leads to significantly decreased serum 2-MeO-E2. Therefore, the PE symptoms induced by coffee treatment is probably mediated by decreased 2-MeO-E2. Our findings provide new mechanistic insight into how coffee intake could lead to increased risk of PE, and demonstrate the effectiveness of 2-MeO-E2 supplementation as a potential therapeutic agent for PE.

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