chlorogenic-acid and 1-methylpyridinium

Coffee consumption has been reported to decrease oxidative damage in peripheral white blood cells (WBC). However, effects on the level of spontaneous DNA strand breaks, a well established marker of health risk, have not been specifically reported yet. We analyzed the impact of consuming a dark roast coffee blend on the level of spontaneous DNA strand breaks.. Healthy men (n = 84) were randomized to consume daily for 4 weeks either 750 ml of fresh coffee brew or 750 ml of water, subsequent to a run in washout phase of 4 weeks. The study coffee was a blend providing high amounts of both caffeoylquinic acids (10.18 ± 0.33 mg/g) and the roast product N-methylpyridinium (1.10 ± 0.05 mg/g). Before and after the coffee/water consumption phase, spontaneous strand breaks were determined by comet assay.. At baseline, both groups exhibited a similar level of spontaneous DNA strand breaks. In the intervention phase, spontaneous DNA strand breaks slightly increased in the control (water only) group whereas they significantly decreased in the coffee group, leading to a 27% difference within both arms (p = 0.0002). Food frequency questionnaires indicated no differences in the overall diet between groups, and mean body weight during the intervention phases remained stable. The consumption of the study coffee substantially lowered the level of spontaneous DNA strand breaks in WBC.. We conclude that regular coffee consumption contributes to DNA integrity.

Topics: Adult; Alkaloids; Antioxidants; Biomarkers; Caffeine; Coffea; Coffee; Cohort Studies; Comet Assay; DNA Breaks; Food Handling; Germany; Hot Temperature; Humans; Leukocytes; Male; Patient Compliance; Pyridinium Compounds; Quinic Acid; Seeds

The hypothesis was tested that coffee types differing in content of major constituents also differ with regard to cardiometabolic effects.. Overweight persons (n = 118) were randomized to consume a dark roast [rich in N-methylpyridinium (NMP)] or medium roast (rich in caffeoylquinic acids, trigonelline) coffee blend for 3 months, after a washout period of 4 weeks. Before and after the intervention period, body weight and 15 further general and biochemical parameters were determined.. Participants consumed an average of 4-5 cups per day. Mean body weight, body mass index and waist circumference did not change during the coffee consumption phase in either of the study groups. Systolic blood pressure decreased in the dark roast coffee group only (p < 0.05). High-density lipoprotein cholesterol levels increased in the medium roast coffee group only, and triglyceride levels increased in the dark roast coffee group only. Glucoregulation and insulin levels were not affected, although there was a small increase of hemoglobin A1c values in both groups. An increase of adiponectin levels occurred in the medium roast coffee group only and was negatively associated with NMP concentrations. Differences did not remain statistically significant after correction for multiple testing.. Medium and dark roast coffee blends exert small but possibly relevant different cardiometabolic effects. Further studies of health outcomes in relation to coffee constituents seem warranted.

Topics: Adiponectin; Adolescent; Adult; Aged; Alkaloids; Blood Glucose; Blood Pressure; Body Mass Index; Body Weight; C-Reactive Protein; Cardiovascular System; Cholesterol, HDL; Cholesterol, LDL; Coffee; Fasting; Female; Glycated Hemoglobin; Humans; Insulin; Linear Models; Male; Middle Aged; Osteopontin; Overweight; Prospective Studies; Pyridinium Compounds; Quinic Acid; Waist Circumference; Weight Loss; Young Adult

Quantitative analysis of the bioactives trigonelline (1), N-methylpyridinium (2), caffeine (3), and caffeoylquinic acids (4) in a large set of roasted Arabica (total sample size n = 113) and Robusta coffees (total sample size n = 38) revealed that the concentrations of 1 and 4 significantly correlated with the roasting color (P < 0.001, two tailed), whereas that of 2 significantly correlated inversely with the color (P < 0.001, two tailed). As dark-roasted coffees were rich in N-methylpyridinium whereas light-roasted coffees were rich in trigonelline and caffeoylquinic acids, manufacturing of roast coffees rich in all four bioactives would therefore necessitate blending of two or even more coffees of different roasting colors. Additional experiments on the migration rates during coffee brewing showed that all four bioactives were nearly quantitatively extracted in the brew (>90%) when a water volume/coffee powder ratio of >16 was used.

Topics: Alkaloids; Caffeine; Coffea; Cooking; Kinetics; Pyridinium Compounds; Quinic Acid; Seeds

Epidemiological studies suggest that coffee can reduce the risk of degenerative diseases such as diabetes type 2, cardiovascular disease and cancer. These beneficial effects have partly been attributed to the antioxidant activity of coffee. We determined composition and antioxidant potential of differentially roasted coffee extracts and investigated the impact of selected original constituents and roast products.. Parameters studied were direct antioxidant activity (trolox equivalent antioxidant capacity/oxygen radical absorbing capacity), cellular reactive oxygen species (ROS) level, DNA damage and protein expression of NAD(P)H: quinone oxidoreductase, γ-glutamylcysteine ligase and glutathione reductase in HT-29/Caco-2 cells at 24-h incubation. All extracts showed distinct direct antioxidant activity: medium roasts>light roast AB1 (caffeoylquinic acid (CQA)-rich Arabica Brazil extract); dark roast AB2 (N-methylpyridinium (NMP)-rich Arabica Brazil extract), and diminished t-butylhydroperoxide-induced ROS level in HT-29 cells (AB2>medium roasts>AB1). NAD(P)H:quinone oxidoreductase 1 expression and γ-glutamylcysteine ligase expression were distinctly induced by AB1 and 5-CQA, but not by AB2 and NMP. 5-CQA and caffeic acid exhibited highest trolox equivalent antioxidant capacity/oxygen radical absorbing capacity values (5-CQA: 1.3/3.5 mM and caffeic acid: 1.3/3.9 mM trolox); ROS level was distinctly diminished by 5-CQA (≥3 μM), catechol (30 μM) and trigonelline (≥30 μM), whereas menadione-induced DNA damage in Caco-2 cells was reduced by NMP compounds (1-30 μM).. The results emphasize that both original constituents and roast products contribute to the cellular antioxidant effectiveness of coffee.

Topics: Antioxidants; Caco-2 Cells; Caffeic Acids; Cell-Free System; Coffee; Colon; DNA Damage; Glutamate-Cysteine Ligase; Glutathione Reductase; HT29 Cells; Humans; NAD(P)H Dehydrogenase (Quinone); Plant Extracts; Pyridinium Compounds; Quinic Acid; Reactive Oxygen Species; tert-Butylhydroperoxide