Chronic coffee and caffeine ingestion effects on the cognitive function and antioxidant system of rat brains

Impacts of Self-Administered 3,4-Methylenedioxypyrovalerone (MDPV) Alone, and in Combination with Caffeine, on Recognition Memory and Striatal Monoamine Neurochemistry in Male Sprague Dawley Rats: Comparisons with Methamphetamine and Cocaine

Recent data suggest that 3,4-methylenedioxypyrovalerone (MDPV) has neurotoxic effects; however, the cognitive and neurochemical consequences of MDPV self-administration remain largely unexplored. Furthermore, despite the fact that drug preparations that contain MDPV often also contain caffeine, little is known regarding the toxic effects produced by the co-use of these two stimulants. The current study investigated the degree to which self-administered MDPV or a mixture of MDPV+caffeine can produce deficits in recognition memory and alter neurochemistry relative to prototypical stimulants. Male Sprague Dawley rats were provided 90 min or 12 h access to MDPV, MDPV+caffeine, methamphetamine, cocaine, or saline for 6 weeks. Novel object recognition (NOR) memory was evaluated prior to any drug self-administration history and 3 weeks after the final self-administration session. Rats that had 12 h access to methamphetamine and those that had 90 min or 12 h access to MDPV+caffeine exhibited significant deficits in NOR, whereas no significant deficits were observed in rats that self-administered cocaine or MDPV. Striatal monoamine levels were not systematically affected. These data demonstrate synergism between MDPV and caffeine with regard to producing recognition memory deficits, highlighting the importance of recapitulating the manner in which drugs are used (e.g., in mixtures containing multiple stimulants, binge-like patterns of intake).

Impacts of Self-Administered 3,4-Methylenedioxypyrovalerone (MDPV) Alone, and in Combination with Caffeine, on Recognition Memory and Striatal Monoamine Neurochemistry in Male Sprague-Dawley Rats: Comparisons with Methamphetamine and Cocaine

Recent data suggest that 3,4-methylenedioxypyrovalerone (MDPV) has neurotoxic effects; however, the cognitive and neurochemical consequences of MDPV self-administration remain largely unexplored. Furthermore, despite the fact that drug preparations that contain MDPV often also contain caffeine, little is known regarding the toxic effects produced by the co-use of these two stimulants. The current study investigated the degree to which self-administered MDPV, or a mixture of MDPV+caffeine can produce deficits in recognition memory and alter neurochemistry relative to prototypical stimulants. Male Sprague-Dawley rats were provided 90-min or 12-h access to MDPV, MDPV+caffeine, methamphetamine, cocaine, or saline for 6 weeks. Novel object recognition (NOR) memory was evaluated prior to any drug self-administration history and 3 weeks after the final self-administration session. Rats that had 12-h access to methamphetamine and those that had 90-min or 12-h access to MDPV+caffeine exhibited significant deficits in NOR, whereas no significant deficits were observed in rats that self-administered cocaine or MDPV. Striatal mono-amine levels were not systematically affected. These data demonstrate synergism between MDPV and caffeine with regard to producing recognition memory deficits and lethality, highlighting the importance of recapitulating the manner in which drugs are used (e.g., in mixtures containing multiple stimulants, binge-like patterns of intake).

Evaluation of the Effects of Instant Cascara Beverage on the Brain-Gut Axis of Healthy Male and Female Rats

Instant cascara (IC) is a sustainable beverage obtained from dried coffee cherry pulp, rich in nutrients and bioactive compounds. The present research aimed to determine the effects of IC on general health and brain-gut axis parameters of healthy female and male rats. Wistar rats were exposed to IC (10 mg/mL) in their drinking water for 3 weeks. Body weight and solid and liquid intakes were monitored as indicators of food safety. Gastrointestinal transit was radiographically evaluated one day (acute) and 3 weeks (chronic) after the start of IC exposure. Locomotor activity, anxiety, and anhedonia of the animals after 3 weeks of treatment was also studied. Overall, compared to water-exposed animals, IC significantly increased food intake in males (p < 0.0001) and liquid intake in females (p < 0.05) without changes in body weight in either case. IC did not significantly modify gastrointestinal motility parameters after its acute or repeated intake and did not cause any significant behavioral alterations in males or females (p > 0.05). In conclusion, repeated intake of IC at the studied concentration did not negatively affect brain-gut axis functions of healthy male and female rats. Anxiety behavior, diarrhea, constipation, abnormal weight modifications, or other typical effects of toxicity were not observed in animals treated with the new powdered beverage, suggesting its food safety under the studied conditions.

Caffeine alleviates anxiety-like behavior and brainstem lesions in a rotenone-induced rat model of Parkinson's disease

BACKGROUND

Parkinson's disease (PD) is a neurodegenerative disorder characterized by motor and non-motor symptoms. In 2016, approximately 6.1 million individuals were affected by PD, with 211,296 deaths attributed to the disease. The understanding of PD initially came from the observation of dopaminergic system alterations in a specific region of the brainstem, indicating that the core motor and non-motor features of PD are closely associated with brainstem dysfunction. The primary treatment approach for PD revolves around dopamine replacement, as many of the symptoms are responsive to this therapeutic intervention. However, long-term administration of this approach is linked to several complications, and a definitive gold-standard therapy for PD is yet to be identified. The pharmacological management of PD has been challenging and inconsistent, mainly due to the unclear underlying cause of the disease. This study aims to evaluate the effects of caffeine on the brainstem of rats with PD induced by rotenone.

METHODOLOGY

Fifty adult male Wistar rats weighing between 150 and 200 g were used in this study. The rats were randomly divided into five groups of ten rats each: Vehicle Group, Rotenone-only treated Group (rotenone only treated with 3 mg/kg, intraperitoneal administration [IP]), Preventive Group (caffeine 30 mg/kg + rotenone 3 mg/kg, IP), Curative Group (rotenone 3 mg/kg + caffeine 30 mg/kg, IP), and Caffeine only treated Group (caffeine only treated with 30 mg/kg, IP). The animals underwent neurobehavioral assessments, followed by sacrifice. The brains were then excised, weighed, and processed histologically. Appropriate brain sections were taken and processed. Photomicrographs were obtained, morphometric and statistical analysis was performed using an Omax LED digital RESULTS: The results demonstrated a significant (p < 0.05) reduction in body weight and relative brain weight, which were increased by caffeine treatments. Rotenone administration led to histological changes similar to those observed in PD, including neuronal structural derangement, degenerated nerve fibers, loss of myelinated neurons, and Nissl substance, as well as downregulation in the expressions of NRF2 and TH in the midbrain. However, these pathological features were counteracted or ameliorated by caffeine treatment.

CONCLUSION

Our study contributes additional evidence to the growing body of research supporting the therapeutic potential of caffeine in Parkinson's disease (PD). The results underscore the neuroprotective properties of caffeine and its capacity to mitigate oxidative stress by modulating TH (tyrosine hydroxylase) and cytoplasmic NRF2 (nuclear factor erythroid 2-related factor 2) in the mesencephalon. These findings suggest that caffeine holds promise as a viable treatment option for PD.

Protective effects of caffeine against palmitate-induced lipid toxicity in primary rat hepatocytes is associated with modulation of adenosine receptor A1 signaling

BACKGROUND

Epidemiological evidence has shown an association between coffee consumption and reduced risk for chronic liver diseases, including metabolic-dysfunction-associated liver disease (MALFD). Lipotoxicity is a key cause of hepatocyte injury during MAFLD. The coffee component caffeine is known to modulate adenosine receptor signaling via the antagonism of adenosine receptors. The involvement of these receptors in the prevention of hepatic lipotoxicity has not yet been explored. The aim of this study was to explore whether caffeine protects against palmitate-induced lipotoxicity by modulating adenosine receptor signaling.

METHODS

Primary hepatocytes were isolated from male rats. Hepatocytes were treated with palmitate with or without caffeine or 1,7DMX. Lipotoxicity was verified using Sytox viability staining and mitochondrial JC-10 staining. PKA activation was verified by Western blotting. Selective (ant)agonists of A1AR (DPCPX and CPA, respectively) and A2AR (istradefyline and regadenoson, respectively), the AMPK inhibitor compound C, and the Protein Kinase A (PKA) inhibitor Rp8CTP were used. Lipid accumulation was verified by ORO and BODIPY 453/50 staining.

RESULTS

Caffeine and its metabolite 1,7DMX prevented palmitate-induced toxicity in hepatocytes. The A1AR antagonist DPCPX also prevented lipotoxicity, whereas both the inhibition of PKA and the A1AR agonist CPA (partially) abolished the protective effect. Caffeine and DPCPX increased lipid droplet formation only in palmitate-treated hepatocytes and decreased mitochondrial ROS production.

CONCLUSIONS

The protective effect of caffeine against palmitate lipotoxicity was shown to be dependent on A1AR receptor and PKA activation. Antagonism of A1AR also protects against lipotoxicity. Targeting A1AR receptor may be a potential therapeutic intervention with which to treat MAFLD.

The relationship between dietary patterns derived from inflammation and cognitive impairment in patients undergoing hemodialysis

Introduction

Dietary patterns were shown to be closely related to inflammation, which was independently associated with cognitive impairment (CI) in patients undergoing hemodialysis (HD). However, it remains unclear the influence of dietary patterns derived from inflammation on CI in this population. This study aimed to examine the association between dietary patterns derived from C-reactive protein (CRP) and interleukin-6 (IL-6) and CI in patients undergoing HD.

Methods

Dietary intake was obtained from the simplified quantitative food frequency questionnaire. Reduced rank regression (RRR) was used to extract two dietary patterns, with IL-6 and CRP as response variables. Cognitive function was examined by the Montreal Cognitive Assessment (Beijing version). Venous blood was drawn for measuring IL-6 and CRP levels. Multivariable logistic regression was used to investigate the association between dietary patterns and CI.

Results

Dietary pattern derived from IL-6 was not significantly associated with CI. The third quartile of dietary pattern, which used CRP as the response variable, significantly contributed to the increased risk of CI (AOR 8.62, 95% CI 1.47-50.67) after controlling age, sex, education level, marital status, and residential pattern (p-for-trend = 0.028). After considering hypertension and diabetes, physical activity level, anxiety and depression, smoking and drinking status, social support, energy intake, and the dietary pattern derived from IL-6 (p-for-trend = 0.026), the relationship between the dietary pattern derived from CRP and CI remained significant (AOR 14.54, 95% CI 1.40-151.13).

Conclusion

Dietary pattern associated with high CRP level, including high intake of rice, liquor, fruit, tea and coffee and low intake of dark vegetables and juice, contributed to the increased risk of CI. The association between the consumption of seafood, sweet beverages, and alcohol and CI is yet to be established. However, they may be dietary contributing factors to inflammation in patients undergoing HD.

Coffee consumption, health benefits and side effects: a narrative review and update for dietitians and nutritionists

Coffee is one of the most popular beverages worldwide; however, its impact on health outcomes and adverse effects is not fully understood. The current review aims to establish an update about the benefits of coffee consumption on health outcomes highlighting its side effects, and finally coming up with an attempt to provide some recommendations on its doses. A literature review using the PubMed/Medline database was carried out and the data were summarized by applying a narrative approach using the available evidence based on the literature. The main findings were the following: first, coffee may contribute to the prevention of inflammatory and oxidative stress-related diseases, such as obesity, metabolic syndrome and type 2 diabetes; second, coffee consumption seems to be associated with a lower incidence of several types of cancer and with a reduction in the risk of all-cause mortality; finally, the consumption of up to 400 mg/day (1-4 cups per day) of caffeine is safe. However, the time gap between coffee consumption and some drugs should be taken into account in order to avoid interaction. However, most of the data were based on cross-sectional or/and observational studies highlighting an association of coffee intake and health outcomes; thus, randomized controlled studies are needed in order to identify a causality link.

Probing Caffeine Administration as a Medical Management for Hydrocephalus: An Experimental Study

BACKGROUND

Hydrocephalus is currently managed by cerebrospinal fluid diversion from the cerebral ventricles to other body sites, but this is complicated by obstruction and infection in young infants, thus adding to morbidity and mortality. Studies have reported caffeine to be a pleiotropic neuroprotective drug in the developing brain due to its antioxidant, anti-inflammatory, and antiapoptotic properties, with improved white matter microstructural development. In this study, we investigate the use of caffeine administration as a possible means of pharmacological management for hydrocephalus.

METHODS

A total of 76 three-day-old mice pups from 10 dams were divided into four groups: hydrocephalus was induced in the pups in two groups by intracisternal injection of kaolin suspension, and their dams were given either caffeine (50 mg/kg by gavage) or water daily for 21 days; the dams in the other 2 (non-hydrocephalic) groups similarly had either caffeine or water; the pups received caffeine administered via lactation. Developmental neurobehavioral tests were performed until day 21, when the pups were sacrificed. Their brains were removed and processed for Cresyl and Golgi staining; both quantitative and qualitative analyses were then carried out.

RESULTS

Improved developmental motor activities and reflexes were observed in the hydrocephalus + caffeine-treated pups. Caffeine administration was associated with reduced cell death and increased dendritic arborization of the neurons in the sensorimotor cortex and striatum of hydrocephalic mice pups.

CONCLUSION

Caffeine administration appears to have promise as an adjunct in hydrocephalus management, and its use needs to be further explored.

The Examination of the Influence of Caffeinated Coffee Consumption on the Concentrations of Serum Prolactin and Selected Parameters of the Oxidative-Antioxidant Balance in Young Adults: A Preliminary Report

We verified whether caffeinated coffee consumption influenced the concentrations of prolactin (PRL) and oxidative stress parameters: total antioxidant status (TAS), ferric reducing antioxidant power (FRAP), total oxidant status (TOS), oxidative stress index (OSI), advanced oxidation protein products (AOPP), uric acid (UA), total bilirubin (T-Bil), albumin (ALB), iron (Fe), calcium (Ca), magnesium (Mg), and inflammatory marker C-reactive protein (CRP)—in blood sera obtained at 15, 60, and 120 minutes after caffeinated coffee intake, in relation to the fasting point. The study participants were 33 young, healthy, nonsmoking volunteers (15 men, 18 women) aged 19-29 years. PRL concentrations significantly decreased ( $p<0.05$ ) after consumption, except at time point 15’ in men ( $p>0.05$ ). In women, FRAP levels significantly increased over time, and significant changes were also observed for UA at 120’ and ALB at 15’. In men, significant changes were found for levels of AOPP at 15’, T-Bil and ALB at 15’, iron at 60’ and 120’, and calcium at 120’. There were no significant differences in the levels of other examined parameters between the defined time points. In conclusion, the substances contained in caffeinated coffee decrease the level of prolactin and may also have an impact on selected parameters of oxidative stress, which could be the basis of future research focused on the identification of new therapeutic targets.

Post-learning caffeine administration improves 'what-when' and 'what-where' components of episodic-like memory in rats

Episodic-like memory (ELM) consists in the capacity of nonhuman animals to remember 'where' and 'when' a specific episode occurred ('what'). Previous studies have showed that Wistar rats can form an ELM, but not after a 24 h retention delay. On the other hand, it has been demonstrated that caffeine can improve episodic memory consolidation in humans. Therefore, we verified whether acute post-sample caffeine administration could improve ELM consolidation in Wistar rats, as well if it could be related to neurochemical changes in the prefrontal cortex and hippocampus - regions related to episodic-like memory processing. 46 Male Wistar Rats, approximately 3 months-old, were divided into four groups as follows: untreated (n = 11), saline (n = 11), caffeine 10 mg ∕kg i.p (n = 12); caffeine 15 mg∕kgi.p (n = 12) and tested in WWWhen/ELM task. The animals treated with caffeine in different dosages (10 mg/kg and 15 mg/kg) discriminated temporally and spatially the objects, respectively. These groups also showed a dopamine renewal rate in the hippocampus, suggesting that there was an increase in the turnover compared with the groups with no caffeine administration. We can conclude that caffeine leads to an improvement in the consolidation of the temporal ('what-when') and spatial ('what-where') aspects of episodic-like memory.

Habitual tea consumption and postoperative delirium after total hip/knee arthroplasty in elderly patients: The PNDABLE study

PURPOSE

To clarify the effects of habitual tea consumption on postoperative delirium (POD) in elderly patients undergoing total hip/knee arthroplasty.

PATIENTS AND METHODS

A prospective cohort study was carried out at Qingdao Municipal Hospital Affiliated to Qingdao University between June 2020 and June 2021. A total of 332 patients aged 65-85 years undergoing total hip/knee arthroplasty under combined spinal and epidural anesthesia were enrolled from the Perioperative Neurocognitive Disorder and Biomarker Lifestyle (PNDABLE) study in the final analysis, consisting of 168 patients with habitual tea consumption and 164 patients with infrequent tea consumption. The primary endpoint was the effects of habitual tea consumption on POD and the incidence of POD, which was assessed by the Confusion Assessment Method (CAM) twice daily during the first 7 postoperative days, and POD severity was measured by the Memorial Delirium Assessment Scale (MDAS). The secondary endpoints were the concentrations of caffeine and tea polyphenols in plasma and cerebrospinal fluid (CSF), which were detected by the enzyme-linked immunosorbent assay.

RESULTS

POD occurred in 61 of 332 patients (18.37%), among whom 19 had habitual tea consumption (5.72%) and 42 had infrequent tea consumption (12.65%). Habitual tea consumption (odds ratio [OR] = 0.370, 95% confidence interval [CI]: 0.205-0.670, P = .001) was significantly associated with POD in the logistic analysis, and then after adjusting for age and American Society of Anesthesiologists (ASA) physical status (OR = 0.353, 95% CI: 0.190-0.655, P = .001). Furthermore, caffeine in T₀ plasma (OR = 0.834, 95% CI: 0.752-0.924, P = .001), T₁ plasma (OR = 0.818, 95% CI: 0.738-0.908, P < .001), and CSF (OR = 0.899, 95% CI: 0.820-0.984, P = .022) and tea polyphenols in T₀ plasma (OR = 0.541, 95% CI: 0.416-0.704, P < .001), T₁ plasma (OR = 0.477, 95% CI: 0.359-0.633, P < .001), and CSF (OR = 0.526, 95% CI: 0.397-0.696, P < .001) were associated with POD after adjusting for age and ASA physical status.

CONCLUSION

Habitual tea consumption may be associated with a lower incidence of POD in elderly patients.

The Impact of Instant Coffee and Decaffeinated Coffee on the Gut Microbiota and Depression-Like Behaviors of Sleep-Deprived Rats

Objective

Based on our previous research, chronic paradoxical sleep deprivation (PSD) can cause depression-like behaviors and microbial changes in gut microbiota. Coffee, as the world’s most popular drink for the lack of sleep, is beneficial to health and attention and can eliminate the cognitive sequelae caused by poor sleep. The purpose of this study is to investigate the effects of coffee and decaffeinated coffee on PSD rats.

Research Design and Methods

A total of 32 rats were divided into four groups: control group, PSD model group, conventional coffee group, and decaffeinated coffee group. Behavioral tests, including sucrose preference test, open field test, forced swimming test, and tail suspension test, as well as biochemical detection for inflammatory and antioxidant indexes were performed. The effects of coffee and decaffeinated coffee on the gut microbiota of PSD rats were investigated by 16S rRNA gene sequencing.

Results

Coffee and decaffeinated coffee significantly improved the depression-like behaviors. Moreover, the serum levels of interleukin-6 and tumor necrosis factor alpha were decreased in both coffee and decaffeinated coffee groups, as well as the levels of superoxide dismutase and GSH-Px were increased. Gut microbiota analysis revealed that the abundance of S24-7, Lachnospiraceae, Oscillospira, and Parabacteroides were significantly increased in PSD rats, while the abundance of Akkermansia and Klebsiella were significantly decreased. After the treatment of coffee and decaffeinated coffee, the abundance of the above gut microbiota was all restored in different degrees. Coffee had relatively more significant effects on PSD-induced depressive-like behaviors, while the difference between coffee and decaffeinated coffee was not obvious in correcting the disorder of gut microbiota.

Conclusions

These findings have shown that both coffee and decaffeinated coffee are effective for sleep deprivation-induced depression-like behaviors and the dysbiosis of gut microbiota and indicated that caffeine may be not the only key substance of coffee for regulating gut microbiota.

Caffeine citrate effects on gastrointestinal permeability, bacterial translocation and biochemical parameters in newborn rats after long-term oral administration

BACKGROUND: Caffeine is a potent central and respiratory acting agent used in neonatology to treat apnea in premature newborns. OBJECTIVE: This study investigates the effects of caffeine orally administered to newborn rats on gastrointestinal permeability, bacterial translocation and different biochemical parameters. METHODS: Newborn rats were divided into different groups (N = 06). The treated newborn rats were orally administered with standard caffeine doses (12 mg/kg per day), and the control groups received a placebo. The animals were weighed daily until sacrifice. Blood samples, mesenteric lymph nodes (MLN) and organs were aseptically collected. Furthermore, different biochemical (D-Lactate) and oxidative stress biomarkers (MDA, CAT, SOD and GSH) levels were examined. Microbiological analyses were performed to assess microbiota alterations and bacterial translocation. RESULTS: Preliminary results showed that caffeine administration decreased the level of bacterial translocation over time. The treatment reduced plasma D-lactate levels (p <  0.05). Additionally, caffeine induced a disturbance in the concentrations of biochemical parameters and oxidative stress biomarkers. Indeed, liver enzymes (AST and ALT) were significantly (p <  0.05) risen after caffeine treatment. Glutathione (GSH) levels were significantly higher in caffeine treated groups (75.12±0.32; 51.98±1.12 U/mg; p <  0.05) comparing to control ones (40.82±0.25; 42.91±0.27 U/mg; p <  0.05) in the ileum and the colon, respectively. CONCLUSIONS: Thus, besides improving gastrointestinal permeability, our data show that caffeine has beneficial effects on the intestinal antioxidant system.

Habitual Tea and Coffee Consumption and Mean Reaction Time Among Qatari Adults

BACKGROUND

Tea and coffee consumption is associated with cognitive function in some studies.

OBJECTIVE

We aimed to identify tea and coffee drinking patterns and their association with mean reaction time among Qatari adults.

METHOD

The study included 1,000 adults aged 20 years and above attending the Qatar Biobank Study (QBB). Habitual tea and coffee consumption during the previous year was assessed by questionnaire. Tea and coffee drinking patterns were identified using factor analysis. In a computer-based self-administered touch screens test, mean reaction time (MRT) was used as an indicator of cognitive function.

RESULTS

The mean age of the participants was 35.8 (SD 10.3) years. Herbal tea and regular coffee consumption was inversely associated with MRT. In the multivariable model, compared with non-consumers, the regression coefficients for MRT were -34.3 (-65.4, -3.3) and -37.9 (-71.0, -4.7) for daily consumers of herbal tea and regular coffee, respectively. Of the two tea and coffee drinking patterns identified, pattern 1 (high consumption of tea, Arabic coffee, and herbal tea) was not associated with MRT but pattern 2 (high loadings of instant coffee, regular coffee, and Karak) was inversely associated with MRT in the unadjusted model. There was a significant interaction between pattern 2 and low-density lipoprotein (LDL) in relation to MRT. Pattern 2 was inversely associated with MRT among those with a low LDL.

CONCLUSION

There was an inverse association between regular coffee and herbal tea consumption with mean reaction time. There was an interaction between Western coffee pattern and LDL.

How does caffeine influence memory? Drug, experimental, and demographic factors

Caffeine is a widely used nootropic drug, but its effects on memory in healthy participants have not been sufficiently evaluated. Here we review evidence of the effects of caffeine on different types of memory, and the associated drug, experimental, and demographical factors. There is limited evidence that caffeine affects performance in memory tasks beyond improved reaction times. For drug factors, a dose-response relationship may exist but findings are inconsistent. Moreover, there is evidence that the source of caffeine can modulate its effects on memory. For experimental factors, past studies often lacked a baseline control for diet and sleep and none discussed the possible reversal of withdrawal effect due to pre-experimental fasting. For demographic factors, caffeine may interact with sex and age, and the direction of the effect may depend on the dose, individual tolerance, and metabolism at baseline. Future studies should incorporate these considerations, as well as providing continued evidence on the effect of caffeine in visuospatial, prospective, and implicit memory measures.

Shifting of Physicochemical and Biological Characteristics of Coffee Roasting Under Ultrasound-Assisted Extraction

Ultrasound-assisted extraction (UAE) is an effective tool for the extraction of natural antioxidants. Thus, differentially roasted Arabica-coffee beans known as light (LC), medium (MC), and dark coffee (DC) were prepared and extracted under the influence of UAE. Following that, they were examined specifically on theirs physicochemical and biological characteristics: nutritional values, pH, °Brix, antioxidant activities, polyphenol content, caffeine, and chlorogenic-acid levels. Various parameters, such as extraction temperatures (20, 40, and 80°C) and extraction time periods (5, 10, and 20 min), were examined. DC extract was less acidic than those on MC and LC extracts. LC showed higher moisture content than the MC and DC (1.56, 1.3, and 0.92%, respectively). MC displayed the highest polyphenol content and potent antioxidant activity. Caffeine and chlorogenic acid contents trend to decrease during roasting. The maximum caffeine level was found in MC at 80°C for 5 min (27.65 mg/g extract). The highest chlorogenic acid content was in LC at 80°C for 10 min (16.67 mg/g extract). The caffeine and chlorogenic acid contents were related to the polyphenol content and depended on the roasting and extraction conditions. These results suggest that the UAE at various temperature and extraction time period may alter the physicochemical and biological characteristics of different coffee roasts.

Current Status of Primary, Secondary, and Tertiary Prevention of Coronary Artery Disease

Fifty percent of all death from cardiovascular diseases is due to coronary artery disease (CAD). This is avoidable if early identification is made. Preventive health care has a major role in the fight against CAD. Atherosclerosis and atherosclerotic plaque rupture are involved in the development of CAD. Modifiable risk factors for CAD are dyslipidemia, diabetes, hypertension, cigarette smoking, obesity, chronic renal disease, chronic infection, high C-reactive protein, and hyperhomocysteinemia. CAD can be prevented by modification of risk factors. This paper defines the primary, secondary, and tertiary prevention of CAD. It discusses the mechanism of risk factor-induced atherosclerosis. This paper describes the CAD risk score and its use in the selection of individuals for primary prevention of CAD. Guidelines for primary, secondary, and tertiary prevention of CAD have been described. Modification of risk factors and use of guidelines for prevention of CAD would prevent, regress, and slow down the progression of CAD, improve the quality of life of patient, and reduce the health care cost.

Natural Antioxidant Application on Fat Accumulation: Preclinical Evidence

Obesity represents one of the most important challenges in the contemporary world that must be overcome. Different pathological consequences of these physical conditions have been studied for more than 30 years. The most nagging effects were found early in the cardiovascular system. However, later, its negative impact was also investigated in several other organs. Damage at cellular structures due to overexpression of reactive oxygen species together with mechanisms that cause under-production of antioxidants leads to the development of obesity-related complications. In this view, the negative results of oxidant molecules due to obesity were studied in various districts of the body. In the last ten years, scientific literature has reported reasonable evidence regarding natural and synthetic compounds' supplementation, which showed benefits in reducing oxidative stress and inflammatory processes in animal models of obesity. This article attempts to clarify the role of oxidative stress due to obesity and the opposing role of antioxidants to counter it, reported in preclinical studies. This analysis aims to clear-up different mechanisms that lead to the build-up of pro-oxidants during obesity and how various molecules of different origins hinder this phenomenon, behaving as antioxidants.

Effects of caffeine on brain antioxidant status and mitochondrial respiration in acetaminophen-intoxicated mice

Hepatic encephalopathy is a pathophysiological complication of acute liver failure, which may be triggered by hepatotoxic drugs such as acetaminophen (APAP). Although APAP is safe in therapeutic concentration, APAP overdose may induce neurotoxicity, which is mainly associated with oxidative stress. Caffeine is a compound widely found in numerous natural beverages. However, the neuroprotective effect of caffeine remains unclear during APAP intoxication. The present study aimed to investigate the possible modulatory effects of caffeine on brain after APAP intoxication. Mice received intraperitoneal injections of APAP (250 mg/kg) and/or caffeine (20 mg/kg) and, 4 h after APAP administration, samples of brain and blood were collected for the biochemical analysis. APAP enhanced the transaminase activity levels in plasma, increased oxidative stress biomarkers (lipid peroxidation and reactive oxygen species), promoted an imbalance in endogenous antioxidant system in brain homogenate and increased the mortality. In contrast, APAP did not induce dysfunction of the mitochondrial bioenergetics. Co-treatment with caffeine modulated the biomarkers of oxidative stress as well as antioxidant system in brain. Besides, survival assays demonstrated that caffeine protective effects could be dose- and time-dependent. In addition, caffeine promoted an increase of mitochondrial bioenergetics response in brain by the enhancement of the oxidative phosphorylation, which could promote a better energy supply necessary for brain recovery. In conclusion, caffeine prevented APAP-induced biochemical alterations in brain and reduced lethality in APAP-intoxicated mice, these effects may relate to the preservation of the cellular antioxidant status, and these therapeutic properties could be useful in the treatment of hepatic encephalopathy induced by APAP intoxication.

Occurrence, fate, persistence and remediation of caffeine: a review

Pharmaceutical and personal care products (PPCPs) have gained attention in recent years due to their continuous discharge in natural waters. Their persistence in the environment has impacted flora, fauna and human being worldwide. One of the most common PPCPs is caffeine (1, 3, 7-trimethylxanthine) which acts as a stimulant to the central nervous system in humans and is found in nature in about 60 plant species, especially in coffee, tea and cacao plants. Here we discuss the evidence with respect to caffeine occurrence, its persistence and remediation in light of increasing knowledge and the impact of caffeine on the environment. Daily intake of caffeine around the world is found to increase due to the frequent introduction of new caffeinated beverages as well as increased consumption of coffee, tea and carbonated soft drinks, which has led to increase in its concentration in water bodies including agricultural soil. The caffeine concentration in different water system, studied by various authors is also described. Diverse effects of the use of caffeine on several organisms including humans are also briefly presented. Therefore, urgent attention for the removal of caffeine and its derivatives is the need of the hour. Various methods described in literature for caffeine degradation/removal is also presented. Another widely used technique in environmental remediation is molecular imprinting (MIP); however, only few MIPs have been demonstrated for caffeine which is also discussed. Regular monitoring can be useful to control toxic effects of caffeine. Graphical abstract.

Caffeine inhalation effects on locomotor activity in mice

It is estimated that 80% of the world's population consumes caffeine from beverages and food every day. The traditional form of caffeine intake is oral, but more recently people have been inhaling caffeine using nasal sprays. However, the effects of caffeine inhalation are not well understood. The purpose of this study was to determine whether caffeine inhalation affects mouse behavior. To test this, we compared spontaneous activity of mice following inhalation and intraperitoneal administration of caffeine. Next, we investigated whether spontaneous activity changed with the time and/or concentration of caffeine inhaled. We found that mice that inhaled caffeine increased their spontaneous activity similar to mice that were administered caffeine intraperitoneally. Furthermore, spontaneous activity increased in an inhalation time-dependent and concentration-dependent manner. These results show that caffeine-induced stimulation also occurs by inhalation in mice, which suggests that caffeine can reach the brain even by inhalation. This study is useful not only for creating new administration methods of caffeine but also for adjusting caffeine storage and management.

The effects of n-butanol on oxidative stress and apoptosis in zebra fish (Danio rerio) larvae

In recent years, n-butanol has growing use in many areas, including the food industry. In this study, acute toxic effects of n-butanol to zebrafish (Danio rerio) larvae by applying different concentrations (10, 50, 250, 500, 750, 1000 and 1250 mg/L) to embryos were evaluated. For this purpose the data of oxidative stress, antioxidant - acetyl cholinesterase enzyme activities, malondialdehyde level and apoptosis were taken into consideration. At the end of the 96 h, antioxidant (Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx)) and acetylcholinesterase (AChE) enzyme activities were decreased, however lipid peroxidation level, apoptotic cells, and reactive oxygen species increased (p < .05). As a result, it has been observed that high concentrations of n-butanol with its amphiphilic structure causes quite intense toxic effects in zebrafish embryos.

Binding Characteristics and Superimposed Antioxidant Properties of Caffeine Combined with Superoxide Dismutase

The binding characteristics and superimposed antioxidant properties of caffeine combined with copper/zinc superoxide dismutase (SOD) were studied. The superimposed antioxidant activity of caffeine with SOD was investigated by detecting the concentration of malondialdehyde (MDA) present in cells, which was induced by hyperthermia and heavy metal exposure. The interactions between the SOD enzyme and caffeine were researched by ultraviolet spectrum, fluorescence spectrum, and molecular computation. The relative amounts of MDA contents of caffeine (0.1 mmol/L), SOD (0.1 mg/L), and caffeine (0.1 mmol/L) and SOD (0.1 mg/L) to water in cells were 0.70, 0.72, and 0.54, respectively, indicating that the antioxidant properties of caffeine combined with SOD may be superimposed. The fluorescence spectroscopy and molecular computation results show that the mixture of caffeine and SOD can result in the formation of a 1:1 complex through hydrogen bond and van der Waals forces spontaneously. The binding constant (K _a) of caffeine with SOD at five different temperatures are 4.41 × 10⁴, 3.30 × 10⁴, 2.29 × 10⁴, 1.71 × 10⁴, and 1.17 × 10⁴ L/mol. The changes of Gibbs-free energy (ΔG) are -26.50, -26.21, -25.71, -25.12, and -24.29 KJ/mol and the ΔG of molecular docking calculation is -26.95 KJ/mol. The experimental results are in accordance with the results of theoretical calculations. The combination of caffeine with SOD can change the conformation and microenvironment of SOD but does not change the activity of SOD. In addition, the combination can superimpose the antioxidant activity of caffeine and SOD.

Effect of caffeine on biomarkers of oxidative stress in lenses of rats with streptozotocin-induced diabetes

INTRODUCTION

One of the major causes of cataract in diabetes is oxidative stress induced by reactive oxygen species (ROS). Nowadays, new substances with antioxidative properties that may prevent cataract development are needed. One such substance is caffeine - an alkaloid with well-documented antioxidative activity.

MATERIAL AND METHODS

The study was conducted on lenses obtained from female rats, divided into 3 groups: control rats; diabetic rats; diabetic rats treated with caffeine at a dose of 20 mg/kg p.o. Type 1 diabetes was induced by streptozotocin (60 mg/kg i.p.). After 4 weeks of caffeine administration, the rats were sacrificed, and the lenses were collected, weighed and homogenized in PBS. The homogenate was used for analysis of protein content, glutathione (GSH) concentration, advanced oxidation protein product (AOPP) concentration, malondialdehyde (MDA) concentration and the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx).

RESULTS

The SOD, CAT and GPx activities were found to be higher in the lenses of diabetic rats. There were also increased MDA and AOPP concentrations as well as decreased GSH concentration. The administration of caffeine resulted in decreased activity of SOD, CAT and GPx. The treatment with caffeine also caused an increase of GSH concentration and a decrease of MDA and AOPP concentrations.

CONCLUSIONS

The results of the present study may be of relevance in determining the effect of caffeine on the processes induced by ROS in vivo. Further, they can be an indication for clinical observations aiming at the assessment of both preventive and therapeutic effects of caffeine in cataract.

Erythropoietin and caffeine exert similar protective impact against neonatal intermittent hypoxia: Apnea of prematurity and sex dimorphism

Apnea of prematurity (AoP) is associated with severe and repeated episodes of arterial oxygen desaturation (intermittent hypoxia - IH), which in turn increases the number of apneas. So far, there is no data addressing whether IH leads to sex-specific respiratory consequences, neither if drugs targeting AoP are more effective in males or females. We used rat pups for investigating whether IH-mediated increase of apneas is sex-specific. We also tested whether caffeine (treatment of choice of AoP), erythropoietin (Epo - a neuroprotective factor and potent respiratory stimulant), and combination of both (caffeine+Epo) prevent the IH-mediated formation of apneas in a sex-dependent manner. Newborn rats exposed to IH (21% - 10% FIO₂-8 h a day - 10 cycles per hour) during postnatal days (P) 3-10 were used in this work. Animals were administered drug vehicle, Epo, caffeine and Epo + caffeine (daily from P3 to P10) gavage. At P10 the frequency of apneas at rest (as an index of respiratory dysfunction induced by IH), and respiratory parameters were measured by plethysmography. Our results showed that IH significantly increases the number of apneas in male but not in female rat pups. Moreover, caffeine and Epo in males similarly prevented the increase of apneas induced by IH, and the administration of both drugs together did not provide a cumulative beneficial effect. No impact of drugs was evidenced in females. Apart from apneas, IH increased the normoxic basal ventilation (ventilation at rest) of male animals, and treatments did not prevent such alteration. Besides, no IH- nor treatment-mediated modulation of basal ventilation was found in the basal ventilation of female animals. Analysis of the activity of pro- and antioxidative molecules revealed that IH induces oxidative stress in the brainstem of male and female animals and that all tested treatments similarly prevented such oxidative imbalance in pups of both sexes. We concluded that neonatal IH and the treatments tested to prevent its respiratory consequences are sex-specific. The mechanics associated with such prevention are directly linked with the prevention of oxidative stress and the maturation of the brain. These findings are relevant to understanding better the AoP disorder and for proposing Epo as a new therapeutical tool.

Caffeine Modulates Cadmium-Induced Oxidative Stress, Neuroinflammation, and Cognitive Impairments by Regulating Nrf-2/HO-1 In Vivo and In Vitro

Cadmium (Cd), a nonbiodegradable heavy metal and one of the most neurotoxic environmental and industrial pollutants, promotes disturbances in major organs and tissues following both acute and chronic exposure. In this study, we assessed the neuroprotective potential of caffeine (30 mg/kg) against Cd (5 mg/kg)-induced oxidative stress-mediated neuroinflammation, neuronal apoptosis, and cognitive deficits in male C57BL/6N mice in vivo and in HT-22 and BV-2 cell lines in vitro. Interestingly, our findings indicate that caffeine markedly reduced reactive oxygen species (ROS) and lipid peroxidation (LPO) levels and enhanced the expression of nuclear factor-2 erythroid-2 (Nrf-2) and hemeoxygenase-1 (HO-1), which act as endogenous antioxidant regulators. Also, 8-dihydro-8-oxoguanine (8-OXO-G) expression was considerably reduced in the caffeine-treated group as compared to the Cd-treated group. Similarly, caffeine ameliorated Cd-mediated glial activation by reducing the expression of glial fibrillary acidic protein (GFAP), ionized calcium-binding adapter molecule 1 (Iba-1), and other inflammatory mediators in the cortical and hippocampal regions of the mouse brain. Moreover, caffeine markedly attenuated Cd-induced neuronal loss, synaptic dysfunction, and learning and cognitive deficits. Of note, nuclear factor-2 erythroid-2 (Nrf-2) gene silencing and nuclear factor-κB (NF-κB) inhibition studies revealed that caffeine exerted neuroprotection via regulation of Nrf-2- and NF-κB-dependent mechanisms in the HT-22 and BV-2 cell lines, respectively. On the whole, these findings reveal that caffeine rescues Cd-induced oxidative stress-mediated neuroinflammation, neurodegeneration, and memory impairment. The present study suggests that caffeine might be a potential antioxidant and neuroprotective agent against Cd-induced neurodegeneration.

Genotoxic effect of caffeine in Yarrowia lipolytica cells deficient in DNA repair mechanisms

Caffeine is a compound that can exert physiological-beneficial effects in the organism. Nevertheless, there are controversies about its protective-antioxidant and/or its negative genotoxic effect. To abound on the analysis of the possible genotoxic/antioxidant effect of caffeine, we used as research model the yeast Yarrowia lipolytica parental strain, and mutant strains (∆rad52 and ∆ku80), which are deficient in the DNA repair mechanisms. Caffeine (5 mM) showed a cytostatic effect on all strains, but after 72 h of incubation the parental and ∆ku80 strains were able to recover of this inhibitory effect on growth, whereas ∆rad52 was unable to recover. When cells were pre-incubated with caffeine and H₂O₂ or incubated with a mixture of both agents, a higher inhibitory effect on growth of mutant strains was observed and this effect was noticeably greater for the Δrad52 strain. The toxic effect of caffeine appears to be through a mechanism of DNA damage (genotoxic effect) that involves DSB generation since, in all tested conditions, the growth of Δrad52 strain (cells deficient in HR DNA repair mechanism) was more severely affected.

Caffeine consumption disrupts hippocampal long-term potentiation in freely behaving rats

Caffeine, one of the most commonly consumed psychoactive substances in the world, has long been known to alter neurological functions, such as alertness, attention, and memory. Despite caffeine's popularity, systematic investigations of its effects on synaptic plasticity in the brain are still lacking. Here we used a freely behaving rodent model of long-term potentiation (LTP), a frequently studied form of synaptic plasticity, to assess the effects of caffeine consumption on hippocampal plasticity. LTP, which is a persistent increase in the strength of synaptic connections between neurons, is a cellular mechanism widely considered to underlie the processes of learning and memory. A group of 10-week-old Sprague-Dawley rats were administered caffeine (1 g/L) in their drinking water 3 weeks prior to collection of electrophysiological data. Another group of age-matched animals received tap water and served as controls. Stimulating and recording electrodes were chronically implanted in the perforant pathway (PP) and dentate gyrus (DG) region of the hippocampus, respectively, to permit stable electrophysiological recordings of synaptic transmission at this synapse. Population spike amplitude (PSA) measures of LTP induction and duration were acquired in vivo while animals were freely behaving using a well-established electrophysiological recording protocol. Results indicate caffeine-treated rats (n = 9) had a significantly (P < 0.05) reduced level of LTP induction compared with controls (n = 10). More studies are needed to identify the exact mechanism through which caffeine alters LTP induction in this freely behaving model of synaptic plasticity.

Potential nutraceutical and food additive properties and risks of coffee: a comprehensive overview

Coffee is a composite mixture of more than a thousand diverse phytochemicals like alkaloids, phenolic compounds, vitamins, carbohydrates, lipids, minerals and nitrogenous compounds. Coffee has multifunctional properties as a food additive and nutraceutical. As a nutraceutical, coffee has anti-inflammatory, anti-oxidant, antidyslipidemic, anti-obesity, type-2 diabetes mellitus (DM), and cardiovascular diseases (CVD), which can serve for the treatment and prevention of metabolic syndrome and associated disorders. On the other hand, as a food additive, coffee has antimicrobial activity against a wide range of microorganisms, inhibits lipid peroxidation (LPO), and can function as a prebiotic. The outcomes of different studies also revealed that coffee intake may reduce the incidence of numerous chronic diseases, like liver disease, mental health, and it also overcomes the all-cause mortality, and suicidal risks. In some studies, high intake of coffee is linked to increase CVD risk factors, like cholesterol, plasma homocysteine and blood pressure (BP). There is also a little evidence that associated the coffee consumption with increased risk of lung tumors in smokers. Among adults who consume the moderate amount of coffee, there is slight indication of health hazards with strong indicators of health benefits. Moreover, existing literature suggests that it may be cautious for pregnant women to eliminate the chances of miscarriages and impaired fetal growth. The primary purpose of this narrative review is to provide an overview of the findings of the positive impacts and risks of coffee consumption on human health. In conclusion, to date, the best available evidence from research indicates that drinking coffee up to 3-4 cups/day provides health benefits for most people.

Caffeine attenuates brain injury but increases mortality induced by high-intensity blast wave exposure

Caffeine is a substance that is consumed worldwide, and it may exert neuroprotective effects against various cerebral insults, including neurotrauma, which is the most prevalent injury among military personnel. To investigate the effects of caffeine on high-intensity blast wave-induced severe blast injury in mice, three different paradigms of caffeine were applied to male C57BL/6 mice with severe whole body blast injury (WBBI). The results demonstrated that chronic caffeine treatment alleviated blast-induced traumatic brain injury (bTBI); however, both chronic and acute caffeine treatments exacerbated blast-induced lung injuries and, more importantly, increased both the cumulative and time-segmented mortalities postinjury. Interestingly, withdrawing caffeine intake preinjury resulted in favorable outcomes in mortality and lung injury, similar to the findings in water-treated mice, and had the trend to attenuate brain injury. These findings demonstrated that although drinking coffee or caffeine preparations attenuated blast-induced brain trauma, these beverages may place personnel in the battlefield at high risk of casualties, which will help us re-evaluate the therapeutic strategy of caffeine application, particularly in multiple-organ-trauma settings. Furthermore, these findings provided possible strategies for reducing the risk of casualties with caffeine consumption, which may help to change the coffee-drinking habits of military personnel.

Coffee, caffeine, chlorogenic acid, and the purinergic system

Coffee is a drink prepared from roasted coffee beans and is lauded for its aroma and flavour. It is the third most popular beverage in the world. This beverage is known by its stimulant effect associated with the presence of methylxanthines. Caffeine, a purine-like molecule (1,3,7 trymetylxantine), is the most important bioactive compound in coffee, among others such as chlorogenic acid (CGA), diterpenes, and trigonelline. CGA is a phenolic acid with biological properties as antioxidant, anti-inflammatory, neuroprotector, hypolipidemic, and hypoglicemic. Purinergic system plays a key role inneuromodulation and homeostasis. Extracellular ATP, other nucleotides and adenosine are signalling molecules that act through their specific receptors, namely purinoceptors, P1 for nucleosides and P2 for nucleotides. They regulate many pathological processes, since adenosine, for instance, can limit the damage caused by ATP in the excitotoxicity from the neuronal cells. The primary purpose of this review is to discuss the effects of coffee, caffeine, and CGA on the purinergic system. This review focuses on the relationship/interplay between coffee, caffeine, CGA, and adenosine, and their effects on ectonucleotidases activities as well as on the modulation of P1 and P2 receptors from central nervous system and also in peripheral tissue.

Caffeine Prevents Memory Impairment Induced by Hyperhomocysteinemia

L-Methionine chronic administration leads to impairment of memory. This impairment is due to the increase in the body oxidative stress, which damages neurons and prevents their firing. On the other hand, caffeine has antioxidant and neuroprotective effects that could prevent impairment of memory induced by L-methionine chronic administration. In the current study, this hypothesis was evaluated. L-methionine (1.7 g/kg/day) was orally administered to animals for 4 weeks and caffeine (0.3 g/L) treatment was added to the drinking water. The radial arm water maze (RAWM) was used to test spatial learning and memory. Antioxidant biomarkers were assessed in the hippocampus tissues using biochemical assay methods. Chronic L-methionine administration induced (short- and long-) term memory impairment (P < 0.05), while caffeine treatment prevented such effect. Additionally, L-methionine treatment reduced catalase and glutathione peroxidase (GPx") enzymatic activities, and reduced glutathione (GSH) to oxidized glutathione (GSSG) ratio. These effects were normalized by caffeine treatment. Activity of superoxide dismutase (SOD) was unchanged by either L-methionine or caffeine treatments. In conclusion, L-methionine induces impairment of memory, and caffeine treatment prevented this impairment probably through affecting hippocampus antioxidant mechanisms.

Acute Administration of Caffeine: The Effect on Motor Coordination, Higher Brain Cognitive Functions, and the Social Behavior of BLC57 Mice

Excessive caffeine consumption causes adverse health effects. The effects of moderate and high doses of caffeine consumption on the motor coordination, cognitive brain functions, and the social behavior in mice were studied. Animals were divided into three groups: control group, moderate dose group (Ac MD), and high dose group (Ac HD). The animals were tested after 7 days of caffeine administration. A rotarod test for motor coordination showed that the mice of the moderate dose group could stay on the rotating rod longer before falling in comparison to the control group and the high dose group. A water maze test for learning and memory showed better performance of mice receiving the moderate dose of caffeine compared to the other groups. Animals that were administered moderate as well as high doses of caffeine showed no sociability and no preference for social novelty in the three-chamber test used to test social behavior. In an elevated plus maze test, control animals showed no anxiety-like behavior while mice from both of the groups administered with caffeine showed anxiety-like behaviors. Our data conclude that the effects of caffeine on higher brain functions depend on the administration dose. When caffeine was given in moderate doses, it resulted in enhancement of memory and motor coordination functions. However, high doses caused defects in memory and learning. The social behavior of the mice, as determined by the level of anxiety and sociability, was affected negatively by moderate as well as high dose caffeine administration.

Sex-dependent modification by chronic caffeine of acute methamphetamine effects on anxiety-related behavior in rats

For fourteen days, male and female PVG/c hooded rats were provided continuously with either pure drinking water, or water containing caffeine in a quantity approximating a daily dose of 31.1 mg/kg. Then at intervals of 3 days, they were administered 1, 2 mg/kg methamphetamine (MA) or saline before being tested for anxiety-related behavior in a zero maze or a light/dark box, or their short-term spatial memory was assessed in a Y maze following introduction of a novel brightness change in one of the arms. Each rat experienced each type of apparatus with the same acute MA or saline treatment while still exposed to chronic caffeine or pure drinking water. While chronic caffeine on its own did not affect any behavioral measure, acute MA was anxiolytic for male rats suggested by increased entries and occupancy of zero-maze enclosed areas, and decreased emergence latencies and increased entries into the light/dark-box light compartment. Females were less affected than males by MA in both types of apparatus unless they also consumed caffeine. For male rats, choices of the Y-maze novel arm were affected by neither caffeine nor MA, but for females provided with unadulterated water, such choices were reduced by 1 mg/kg MA but increased for those exposed to caffeine, thereby suggesting either impaired or improved memory respectively. However, changes in anxiety could also explain these results. Overall, results generated in the three types of apparatus supported potentiation by caffeine of any effects of MA on anxiety for females only.

Sucrose or sucrose and caffeine differentially impact memory and anxiety-like behaviours, and alter hippocampal parvalbumin and doublecortin

Caffeinated sugar-sweetened "energy" drinks are a subset of soft drinks that are popular among young people worldwide. High sucrose diets impair cognition and alter aspects of emotional behaviour in rats, however, little is known about sucrose combined with caffeine. Rats were allocated to 2 h/day 10% sucrose (Suc), 10% sucrose plus 0.04% caffeine (CafSuc) or control (water) conditions. The addition of caffeine to sucrose appeared to increase the rewarding aspect of sucrose, as the CafSuc group consumed more solution than the Suc group. After 14 days of intermittent Suc or CafSuc access, anxiety was assessed in the elevated plus maze (EPM) prior to their daily solution access, whereby CafSuc and Suc rats spent more time in the closed arms, indicative of increased anxiety. Following daily solution access, CafSuc, but not Suc, rats showed reduced anxiety-like behaviour in the open-field. Control and CafSuc rats displayed intact place and long-term object memory, while Suc showed impaired memory performance. Sucrose reduced parvalbumin immunoreactivity in the hippocampus, but no differences were observed between Control and CafSuc conditions. Parvalbumin reactivity in the basolateral amygdala did not differ between conditions. Reduced doublecortin immunoreactivity in the dentate gyrus relative to controls was seen in the CafSuc, but not Suc, treatment conditions. These findings indicate that the addition of caffeine to sucrose attenuated cognitive deficits. However, the addition of caffeine to sucrose evoked anxiety-like responses under certain testing conditions, suggesting that frequent consumption of caffeinated energy drinks may promote emotional alterations and brain changes compared to standard soft drinks.

Perinatal exposure to energy drink induces oxidative damage in the liver, kidney and brain, and behavioral alterations in mice offspring

The worldwide consumption of energy drinks (EDs) has increased in recent years. EDs have several side effects and can be linked to liver injury, kidney damage and risk-seeking behavior. The impact of perinatal consumption of EDs on the newborns has not been previously investigated. In this study, we evaluated the effects of perinatal exposure to a caffeinated ED on the liver, kidney, brain, locomotor activity and anxiety in mice newborns. Pregnant mice received 2.5 or 5 ml ED by oral gavage from the first day of pregnancy until day 15 after birth. Perinatal exposure to the ED induced a significant increase in lipid peroxidation and declined antioxidant defenses in the liver, kidney, cerebrum, cerebellum and medulla oblongata of the newborns at days 21 and 35 after birth. ED induced several histological alterations, including vacuolations and lipid infiltration of hepatocytes, developing and degenerated glomeruli and dilated urinary spaces in the renal cortex, pyknosis and chromatolysis of the cerebral and medullary neurons, and degenerated and abnormal Purkinje cells in the cerebellum. In addition, ED increased the locomotion and induced anxiety-like behavior in mice newborns. In conclusion, perinatal exposure to EDs induces oxidative stress, tissue injury and behavioral alterations in the mice newborns. Therefore, the consumption of EDs during pregnancy and lactation has a negative impact on the newborns and should be treated as a significant health problem that warrants attention.

Neurochemical and Neurotoxic Effects of MDMA (Ecstasy) and Caffeine After Chronic Combined Administration in Mice

MDMA (3,4-methylenedioxymethamphetamine) is a psychostimulant popular as a recreational drug because of its effect on mood and social interactions. MDMA acts at dopamine (DA) transporter (DAT) and serotonin (5-HT) transporter (SERT) and is known to induce damage of dopamine and serotonin neurons. MDMA is often ingested with caffeine. Caffeine as a non-selective adenosine A1/A2A receptor antagonist affects dopaminergic and serotonergic transmissions. The aim of the present study was to determine the changes in DA and 5-HT release in the mouse striatum induced by MDMA and caffeine after their chronic administration. To find out whether caffeine aggravates MDMA neurotoxicity, the content of DA and 5-HT, density of brain DAT and SERT, and oxidative damage of nuclear DNA were determined. Furthermore, the effect of caffeine on MDMA-induced changes in striatal dynorphin and enkephalin and on behavior was assessed. The DA and 5-HT release was determined with in vivo microdialysis, and the monoamine contents were measured by HPLC with electrochemical detection. DNA damage was assayed with the alkaline comet assay. DAT and SERT densities were determined by immunohistochemistry, while prodynorphin (PDYN) and proenkephalin were determined by quantitative PCR reactions. The behavioral changes were measured by the open-field (OF) test and novel object recognition (NOR) test. Caffeine potentiated MDMA-induced DA release while inhibiting 5-HT release in the mouse striatum. Caffeine also exacerbated the oxidative damage of nuclear DNA induced by MDMA but diminished DAT decrease in the striatum and worsened a decrease in SERT density produced by MDMA in the frontal cortex. Neither the striatal PDYN expression, increased by MDMA, nor exploratory and locomotor activities of mice, decreased by MDMA, were affected by caffeine. The exploration of novel object in the NOR test was diminished by MDMA and caffeine. Our data provide evidence that long-term caffeine administration has a powerful influence on functions of dopaminergic and serotonergic neurons in the mouse brain and on neurotoxic effects evoked by MDMA.

Association of Coffee Consumption with MRI Markers and Cognitive Function: A Population-Based Study

BACKGROUND

Coffee is one of the most widely consumed beverages worldwide and has been of considerable interest in research on cognition and dementia.

OBJECTIVE

To investigate the effect of coffee on preclinical brain MRI markers of dementia and cognitive performance.

METHODS

In 2,914 participants from the population-based Rotterdam Study (mean age: 59.3±7.2 years, 55% females), we assessed coffee consumption, performed brain MRI, and assessed cognition at baseline. To study cognitive change, cognitive assessment was repeated after 5 years of follow-up. Coffee consumption was analyzed continuously (per cup increase) and in categories (0-1, >1-3, >3 cups/day). Using logistic and linear regression, associations of coffee consumption with lacunar infarcts and brain tissue volumes on MRI, and cognitive performance (cross-sectional and longitudinal) were investigated, adjusting for relevant confounders.

RESULTS

We found that higher coffee consumption was associated with a lower prevalence of lacunar infarcts [odds ratio per cup increase: 0.88 (95% CI:0.79;0.98)], and smaller hippocampal volume [difference: -0.01 (95% CI:-0.02;0.00)]. Also, we found that the highest category of coffee consumption was associated with better performance on the Letter Digit Substitution Task [difference: 1.13(95% CI:0.39;1.88)], Word Fluency test [0.74(95% CI:0.04,1.45)], Stroop interference task [1.82(95% CI:0.23;3.41)], and worse performance on the 15-Word Learning test delayed recall [-0.38(95% CI:-0.74;-0.02)]. These associations were not found when cognition was analyzed longitudinally.

CONCLUSION

We found complex associations between coffee consumption, brain structure, and cognition. Higher coffee consumption was cross-sectionally associated with a lower occurrence of lacunar infarcts and better executive function, but also with smaller hippocampal volume and worse memory function.

Caffeine prevents bilirubin-induced cytotoxicity in cultured newborn rat astrocytes

OBJECTIVE

Unconjugated bilirubin (UCB) may cause neurotoxicity in preterm neonates due to immaturity of UGT1A1 leading to bilirubin accumulation in the brain. Caffeine used in the treatment of apnea of prematurity was reported to decrease mechanical ventilation requirement, the frequencies of bronchopulmonary dysplasia, patent ductus arteriosus, cerebral palsy and neurodevelopmental disorders in very low birth weight infants. However, the effect of caffeine on hyperbilirubinemia was not yet clarified.

METHODS

We used astrocyte cell cultures obtained from 2-day-old Wistar albino rats via modified Cole and de Vellis method. UCB concentration toxic to 50% of astrocytes, and caffeine concentration increasing cell viability 100% were used in experiments. While no medication was applied to the control group, UCB (50 μM) and caffeine (100 μM) were applied to the bilirubin and caffeine groups for 24 h. Prophylactic and therapeutic caffeine groups were treated with caffeine 4 h before and after UCB exposure. The effects of caffeine were investigated in rat astrocytes exposed to UCB in terms of cell viability, apoptosis, antioxidant defense, proinflammatory cytokines, and Toll-like receptor (TLR)s.

RESULTS

Compared to the control group, UCB increased apoptosis, malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, total nitrate/nitrite, and TLR4 levels, and decreased cell viability, catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD) activities, glutathione, and TLR9 levels (for all p < .001). Conversely, prophylactic and therapeutic caffeine improved the detrimental effects of UCB.

CONCLUSIONS

Caffeine seems encouraging for the prevention and treatment of bilirubin neurotoxicity in rats by means of its antiapoptotic, antioxidant, anti-inflammatory, anti-nitrosative, and anti-TLR-4 properties.

Effect of caffeine, caffeic acid and their various combinations on enzymes of cholinergic, monoaminergic and purinergic systems critical to neurodegeneration in rat brain-In vitro

Caffeine and caffeic acid are two bioactive compounds that are present in plant foods and are major constituent of coffee, cocoa, tea, cola drinks and chocolate. Although not structurally related, caffeine and caffeic acid has been reported to elicit neuroprotective properties. However, their different proportional distribution in food sources and possible effect of such interactions are not often taken into consideration. Therefore, in this study, we investigated the effect of caffeine, caffeic acid and their various combinations on activities of some enzymes [acetylcholinesterase (AChE), monoamine oxidase (MAO) ecto-nucleoside triphosphate diphosphohydrolase (E-NTPase), ecto-5¹-nucleotidase (E-NTDase) and Na⁺/K⁺ ATPase relevant to neurodegeneration in vitro in rat brain. The stock concentration of caffeine and caffiec acid and their various proportional combinations were prepared and their interactions with the activities of these enzymes were assessed (in vitro) in different brain structures. The Fe²⁺ and Cu²⁺ chelating abilities of the samples were also investigated. The results revealed that caffeine, caffeic acid and their various combinations exhibited inhibitory effect on activities of AChE, MAO, E-NTPase and E-NTDase, but stimulatory effect on Na⁺/K⁺ ATPase activity. The combinations also exhibited Fe²⁺ and Cu²⁺ chelating abilities. Considering the various combinations, a higher caffeine to caffeic acid ratio produced significantly highest enzyme modulatory effects; these were significantly lower to the effect of caffeine alone but significantly higher than the effect of caffeic acid alone. These findings may provide new insight into the effect of proportional combination of these bioactive compounds as obtained in many foods especially with respect to their neuroprotective effects.