Leaf extract of Coffea arabica L. reduces lipid peroxidation and has anti-platelet effect in a rat dyslipidemia model

Abstract This study aimed to evaluate the antioxidant potential of the Coffea arabica Lineu (L.) leaf extract and its effects on platelet aggregation of dyslipidemic rats. The extract was obtained by the percolation of C. arabica L. leaves in hydroethanolic solution 70% (v/v). The mass spectrometry FIA-ESI-MS² suggested the presence of chlorogenic acid, rutin acid, and quinic acid. The DPPH• radicals scavenging capacity was demonstrated (IC50 = 0.06 mg/mL). The extract was administered to rats by gavage (300 mg/kg/day) for 56 days. Dyslipidemia was induced by administering Triton WR-1339 (300 mg/kg body weight) on the 54th day. On day 56, blood was collected by puncturing the abdominal aorta artery and the aortic artery was removed. Lipid profile, markers of renal and hepatic injury, lipid peroxidation, and platelet aggregation tests were carried out. The ingestion of extract reduced the lipid peroxidation (aorta and plasma) and platelet aggregation in dyslipidemic rats. The extract did not affect markers of renal and hepatic function as analyzed in this study, suggesting neither impaired liver nor kidney function in these animals. Therefore, our results demonstrate that the extract of leaves of C. arabica L. show antioxidant potential in vitro and in vivo as well as anti-platelet aggregation in dyslipidemic animals

Coffee consumption and risk of hypertension in the Polish arm of the HAPIEE cohort study.

BACKGROUND/OBJECTIVES: Coffee consumption has been hypothesized to be associated with blood pressure (BP), but previous findings are not homogeneous. The aim of this study was to evaluate the association between coffee consumption and the risk of developing hypertension. SUBJECTS/METHODS: Data on coffee consumption, BP and use of anti-hypertensive medicament were derived from 2725 participants of the Polish arm of the HAPIEE project (Health, Alcohol and Psychosocial factors In Eastern Europe) who were free of hypertension at baseline and followed up for an average of 5 years. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by multivariate logistic regression analyses and stratified for potential confounding factors. RESULTS: Coffee consumption was related to decreased age, smoking status and total energy intake. Compared with persons who drink <1 cup coffee per day, systolic BP was significantly associated with coffee consumption and the risk of hypertension was lower for individuals consuming 3-4 cups per day. Despite the analysis stratified by gender showed that the protective effect of coffee consumption on hypertension was significant only in women, the analysis after stratification by smoking status revealed a decreased risk of hypertension in non-smokers drinking 3-4 cups of coffee per day in both sexes (OR 0.41, 95% CI: 0.21, 0.79 for men and OR 0.54, 95% CI: 0.29, 0.99 for women). Upper category coffee consumption (>4 cups per day) was not related to significant increased risk of hypertension. CONCLUSIONS: Relation between coffee consumption and incidence of hypertension was related to smoking status. Consumption of 3-4 cups of coffee per day decreased the risk of hypertension in non-smoking men and women only.

Identification of two metallothioneins as novel inhalative coffee allergens cof a 2 and cof a 3.

BACKGROUND: Dust of green coffee beans is known to be a relevant cause for occupational allergic disorders in coffee industry workers. Recently, we described the first coffee allergen (Cof a 1) establishing an allergenic potential of green coffee dust. OBJECTIVE: Our aim was to identify allergenic components of green coffee in order to enhance inhalative coffee allergy diagnosis. METHODS: A Coffea arabica pJuFo cDNA phage display library was created and screened for IgE binding with sera from allergic coffee workers. Two further coffee allergens were identified by sequence analysis, expressed in E. coli, and evaluated by Western blots. The prevalence of sensitization to recombinant Cof a 1, Cof a 2, and Cof a 3 and to commercially available extract was investigated by ELISA (enzyme-linked immunosorbent assay) respectively CAP (capacity test) screening in 18 sera of symptomatic coffee workers. RESULTS: In addition to the previously described chitinase Cof a 1, two Coffea arabica cysteine-rich metallothioneins of 9 and 7 kDa were identified and included in the IUIS Allergen Nomenclature as Cof a 2 and Cof a 3. Serum IgE antibodies to at least one of the recombinant allergens were found in 8 out of 18 symptomatic coffee workers (44%). Only 2 of the analysed sera (11%) had reacted previously to the commercial allergy test. CONCLUSIONS: In addition to the previously described Cof a 1 we have identified two further coffee proteins to be type I coffee allergens (Cof a 2 and Cof a 3) which may have a relevant potential for the specific diagnosis and/or therapy of coffee allergy.

Coffee consumption and risk of gastric cancer: a large updated meta-analysis of prospective studies.

The potential role of coffee consumption in the development of various types of cancer has been extensively investigated in epidemiologic studies. How coffee consumption may modulate risk of gastric cancer, however, remains a subject open for investigation. To better quantify this relation, we quantitatively summarized evidence from prospective studies. Eligible studies were identified on PubMed and Embase databases. The summary risk estimates were obtained using the random-effects model. Subgroup, sensitivity and dose-response analyses were conducted. The present meta-analysis included 12 prospective cohort studies. A pooled analysis of these studies suggested that coffee consumption (highest vs. lowest consumption) was not associated with risk of gastric cancer (RR = 1.12, 95% CI = 0.93-1.36). In the subgroup analysis, significant increased risk was detected in the U.S. studies (RR = 1.36, 95% CI = 1.06-1.74) and in the studies with <10 years of follow-up (RR = 1.24, 95% CI = 1.00-1.54), and the greatest increase in risk was observed in those studies without adjustment for smoking (RR = 1.48, 95% CI = 1.13-1.93). There was some evidence of publication bias (P for Egger's test = 0.03). Cumulative evidence from prospective studies suggests that coffee consumption is not associated with risk of gastric cancer. The observed positive results may be confounded by smoking and need further investigation.

Respiratory inflammation among workers exposed to airborne dust with endotoxins in a coffee curing factory.

OBJECTIVE: To study dust exposure and inflammatory reactions in the respiratory tract among coffee curing workers in Tanzania. METHODS: A cross-sectional study was conducted in a Tanzanian coffee curing factory. Coffee workers (n = 15) were compared with unexposed controls (n = 18); all workers were nonsmokers. Exhaled nitric oxide was examined using an electrochemistry-based NIOX MINO device. Personal air samples were analyzed for total dust and endotoxins, using gravimetric analysis and the chromogenic Limulus amebocyte lysate endpoint assay, respectively. RESULTS: Total dust levels ranged from 0.2 to 27.9 mg/m, and endotoxin levels ranged from 42 to 75,083 endotoxin units/m. Concentrations of exhaled nitric oxide, analyzed by linear regression and adjusted for age (ß = 0.57; 95% confidence interval, 0.08 to 1.06; P = 0.02), was higher among coffee workers than among the control group. CONCLUSION: The results indicate a relationship between the coffee dust and signs of respiratory inflammation.

Cof a 1: identification, expression and immunoreactivity of the first coffee allergen.

BACKGROUND: Over the past years, dust of green coffee beans has become known to be a relevant cause for occupational type I allergies. Up to now, allergy diagnostics is based on native green coffee bean extract which exhibits insufficient specificity due to interfering substances as well as batch-to-batch variations. No coffee allergen has been described on the molecular level so far. The aim of this study was to identify the first allergen of green coffee. METHODS: The allergenicity of native green coffee bean extracts was analyzed by means of ImmunoCAP in sera of 17 symptomatic coffee workers. A Coffea arabica pJuFo cDNA phage display library was constructed and screened for IgE binding to coffee proteins with 2 sera from allergic coffee workers. By sequence analysis, a new coffee allergen (Cof a 1) was identified, expressed in Escherichia coli, and evaluated by Western blots. The frequency of sensitization was investigated by ELISA screening. RESULTS: The Cof a 1 cDNA encoded a 32-kDa C. arabica class III chitinase. Serum IgE antibodies to the recombinant allergen were found in 3 out of 17 symptomatic coffee workers (18%), whereas only 2 of them reacted to the commercial allergy test. CONCLUSIONS: A class III chitinase of C. arabica was identified to be the first known coffee allergen Cof a 1. It may have a relevant potential for the specific diagnosis of coffee sensitization.

Coffee consumption and incidence of heart failure in women.

BACKGROUND: Previous studies of the relationship between coffee consumption and incidence of heart failure (HF) have not been consistent, with both potential benefit and potential harm reported. We therefore examined the association between coffee consumption and HF hospitalization or mortality in women. METHODS AND RESULTS: We conducted a prospective, observational study of 34 551 participants of the Swedish Mammography Cohort who were 48 to 83 years old and did not have HF, diabetes, or myocardial infarction at baseline. Diet was measured using food-frequency questionnaires. Cox models were used to calculate hazard ratios of HF hospitalization or death from HF as the primary cause, as determined through the Swedish inpatient and cause-of-death registers between January 1, 1998, and December 31, 2006. Over 9 years of follow-up, 602 HF events occurred. Women who consumed ≥5 cups of coffee per day did not have higher rates of HF events than those who consumed <5 cups per day (multivariable-adjusted hazard ratio, 0.93; 95% confidence interval, 0.72 to 1.20). Compared with women who consumed ≤1 cup of coffee per day, hazard ratios were 1.01, 0.82, 0.94, and 0.87 for women who consumed 2, 3, 4, and ≥5 cups per day, respectively (P for trend=0.23). Further adjustment for self-reported hypertension did not change the results. CONCLUSIONS: In this population of middle-aged and older women, we did not find an association between coffee consumption and incidence of HF events.

Medical records documentation of constipation preceding Parkinson disease: A case-control study.

OBJECTIVE: Parkinson disease (PD) may affect the autonomic nervous system and may cause constipation; however, few studies have explored constipation preceding the motor onset of PD. We investigated constipation preceding PD using a case-control study design in a population-based sample. METHODS: Using the medical records-linkage system of the Rochester Epidemiology Project, we identified 196 subjects who developed PD in Olmsted County, MN, from 1976 through 1995. Each incident case was matched by age (+/-1 year) and sex to a general population control. We reviewed the complete medical records of cases and controls in the medical records-linkage system to ascertain the occurrence of constipation preceding the onset of PD (or index year). RESULTS: Constipation preceding PD or the index year was more common in cases than in controls (odds ratio [OR] 2.48; 95% confidence interval [CI] 1.49 to 4.11; p = 0.0005). This association remained significant after adjusting for smoking and coffee consumption (ever vs never), and after excluding constipation possibly induced by drugs. In addition, the association remained significant in analyses restricted to constipation documented 20 or more years before the onset of motor symptoms of PD. Although the association was stronger in women than in men and in patients with PD with rest tremor compared with patients with PD without rest tremor, these differences were not significant. CONCLUSIONS: Our findings suggest that constipation occurring as early as 20 or more years before the onset of motor symptoms is associated with an increased risk of Parkinson disease.

Smoking and tea consumption delay onset of Parkinson's disease.

Cigarette smoking, coffee and tea drinking may protect against Parkinson's disease (PD). These factors were assessed, retrospectively, to measure their effect on the age of PD onset. The study population consisted of 278 consecutive PD patients. Smoking > or =10 pack-years delayed age of PD onset by 3.2 years (p<0.05). Consumption of tea more than 3 cups per day delayed age of motor symptoms onset by 7.7 years (p<0.01). Coffee consumption exceeding 3 cups per day advanced the age of PD onset by 4.8 years (p=0.03). Thus, tea consumption and smoking can delay the age of PD onset, while coffee drinking may have the opposite effect.

Consequences of prolonged caffeine administration and its withdrawal on pilocarpine- and kainate-induced seizures in rats.

PURPOSE: To investigate the consequences of caffeine consumption on epileptic seizures, we used the pilocarpine and the kainate models of epilepsy. We hypothesized that prolonged caffeine consumption or its withdrawal would alter adenosine levels and hence alter seizure susceptibility. METHODS: We administered a 0.1% caffeine solution in the drinking water of adult male Wistar rats over a 2-week period. We challenged another group of animals with the same doses of pilocarpine or kainate 12 h after the withdrawal of the same caffeine-administration protocol. RESULTS: This did not alter the threshold for the induction of seizures by a subconvulsant dose of pilocarpine (200 mg/kg, i.p.) or kainic acid (8 mg/kg, i.p.). Similarly, challenging another group of animals with the same doses of pilocarpine or kainate 12 h after the withdrawal of the same caffeine-administration protocol did not lead to any significant changes in seizures. CONCLUSIONS: With the pilocarpine model of epilepsy, we were not able to find any significant difference in seizure profile that could stem from either caffeine administration or its withdrawal. Despite the extensive laboratory evidence on the convulsant properties of xanthine derivatives in animal models of epilepsy, such strong evidence is lacking in clinical settings. Our current findings with the administration of caffeine at doses similar to those of daily life both support and confirm the clinical experience.

Environmental exposure, chlorinated drinking water, and bladder cancer.

Environmental and/or occupational factors have been proposed to play a critical role in urological malignancies and, in particular, in bladder cancer. Epidemiological studies have demonstrated with sufficient evidence that factors such as smoking and exposure to aromatic amines, paints and solvents, leather dust, inks, some metals, polycyclic aromatic hydrocarbons, combustion products, or diesel exhaust fumes are associated with the development of bladder cancer. Candidates with an uncertain potential for inducing this type of cancer include dietary factors, specifically fats and cholesterol, and the exposure to contaminants in drinking water. This chapter will describe and discuss the respective literature on environmental and occupational factors linked to carcinogenesis in bladder cancer. For several reasons, the potential effects of tea and coffee consumption will also be considered. A solid epidemiological evaluation of environmental and occupational factors linked to carcinogenesis has to meet many challenges: the number of confounding factors is often large, exposure needs to be determined retrospectively, and elevation of the attributable risk is low in most cases. In view of the long-term exposure of the vast majority of the population to, for instance, drinking- water contaminants, however, the impact of even small elevations of risk warrants evaluation. This complex task needs comprehensive approaches on a large scale including modern analytical, molecular biological and epidemiological methods.