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Background: The P2X(7) receptor plays an important role in cytokine release during the inflammatory response in vivo. Polymorphisms within the P2X(7) receptor gene that lead to loss of receptor function may contribute to impaired cytokine release by immune cells. Therefore, we investigated whether a known loss-of-function polymorphism (Glu496Ala) in the P2X(7) receptor gene leads to alterations in cytokine release in response to ATP., Results: An ex vivo whole blood model was used to induce an inflammatory reaction with the pro-inflammatory stimuli LPS and PHA (phytohemagglutinin). Blood from n=9 subjects with the Glu496Ala P2X7 SNP (P2X7MUT) and n=7 'wild-type' subjects (no P2X7 SNP; P2X7WT) was used.Addition of ATP (0.9-3 mM) to LPS/PHA-stimulated whole blood induced an increase in IL-1β release in P2X7MUT subjects, whereas decreased release was observed in P2X7WT subjects. Decreased levels of IL-6 and TNF-α in response to ATP were shown in both P2X7MUT and P2X7WT subjects, which was less pronounced in P2X7MUT subjects. ATP at 3 mM also significantly decreased levels of lactate dehydrogenase (LDH) in P2X7MUT subjects compared to P2X7WT subjects., Conclusions: The presence of the non-synonymous Glu496Ala loss-of-function polymorphism within the P2X(7) receptor gene is likely to be of importance in the release of cytokines during inflammation. Furthermore, this study suggests that carriers of the Glu496Ala loss-of-function polymorphism are protected against the cytotoxic effects of high ATP-levels.

Purinergic receptors are important for the regulation of inflammation, muscle contraction, neurotransmission and nociception. Extracellular ATP and its metabolites are the main ligands for these receptors. Occasional reports on beneficial results of ATP administration in human and animal studies have suggested the bioavailability of oral ATP supplements. We investigated whether prolonged daily intake of oral ATP is indeed bioavailable. Thirty-two healthy subjects were randomised to receive 0, 250, 1250 or 5000 mg ATP per d for 28 d by means of enteric-coated pellets. In addition, on days 0 and 28, all thirty-two subjects received 5000 mg ATP to determine whether prolonged administration would induce adaptations in the bioavailability of ATP. ATP supplementation for 4 weeks did not lead to changes in blood or plasma ATP concentrations. Of all ATP metabolites, only plasma uric acid levels increased significantly after the administration of 5000 mg of ATP. Prolonged administration of ATP was safe as evidenced from liver and kidney parameters. We conclude that oral administration of ATP only resulted in increased uric acid concentrations. On the basis of these findings, we seriously question the claimed efficacy of oral ATP at dosages even lower than that used in the present study.

Context: One potential agent to improve symptoms and quality of life (QoL) in advanced cancer patients is adenosine 5'-triphosphate (ATP). Several reports suggest that ATP may positively affect QoL and survival in patients with advanced non-small-cell lung cancer., Objectives: To investigate the effects of ATP infusions on QoL parameters in patients with preterminal cancer of mixed tumor types., Methods: Ninety-nine preterminal cancer patients were randomly allocated to receive either ATP intravenously weekly (8-10 hours/week, with maximum 50 μg/kg.minute) for eight weeks or receive no ATP (control group). QoL parameters were assessed until eight weeks and analyzed by repeated-measures analysis of covariance., Results: Fifty-one patients were randomized to the ATP group and 48 to the control group. Unexpectedly, in the untreated control group, most of the outcome parameters did not deteriorate but remained stable or even significantly improved over time. Between the ATP and control groups, no statistically significant differences were observed for the large majority of outcome parameters, except for the strength of elbow flexor muscles in favor of the control group., Conclusion: ATP infusions, at the dose and schedule studied, did not have a significant effect on QoL, functional status, or fatigue in preterminal cancer patients of mixed tumor types., (Copyright © 2010 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.)

Platinum resistance of cancer cells may evolve due to a decrease in intracellular drug accumulation, decreased cell permeability or by an increased deactivation of the drug by glutathione (GSH). The aim of this study was (1) to investigate the effect of adenosine 5'-triphosphate (ATP) on the cytotoxicity of cisplatin in a large cell lung carcinoma cell line (H460), and (2) to examine the potential involvement of increased cisplatin uptake, GSH depletion and pyrimidine starvation by ATP in this effect. H460 cells were harvested and seeded (5% CO(2); 37 degrees C). Subsequently, cells were incubated with medium or ATP followed by an incubation with cisplatin. Cytotoxicity screening was analyzed by the sulforhodamine B (SRB) colorimetric assay, lactate dehydrogenase and caspase-3/7 activity. Pre-incubation for 72h with 0.3 and 3mM ATP strongly enhanced the anti-proliferative potency of cisplatin 2.9- and 7.6-fold, respectively. Moreover, after incubation of H460 cells with 0.3mM ATP the intracellular platinum concentration increased, indicating increased cisplatin uptake by ATP. ATP, despite lowering the LD(50) of cisplatin, did not modulate GSH levels in H460 cells. ATP itself showed a biphasic effect on H460 cell growth: 0.3mM inhibited H460 cell growth via the pyrimidine starvation effect, activation of caspase-3/7 and LDH leakage, while 3mM ATP showed no effect on cell growth. In conclusion, ATP sensitizes the H460 cells to cisplatin-induced apoptosis. The effect of 0.3mM ATP is not due to GSH depletion but involves increased cisplatin uptake and pyrimidine starvation due to ATP conversion to adenosine followed by cellular uptake.

The aim of the study was to investigate the effect of intravenous infusions of adenosine 5'-triphosphate (ATP) on nutritional status and survival in preterminal cancer patients. Ninety-nine preterminal cancer patients (estimated life expectancy 1-6 months) with mixed tumor types were randomly allocated to receive either intravenous ATP weekly (8-10 h/week, maximum 50 microg/kg/min) for 8 weeks, or no ATP (control group). Nutritional status parameters were assessed until 8 weeks, and analyzed by repeated-measures analysis of covariance. Cox proportional hazards models were fitted to assess the effect of ATP on short-term (0-8 weeks) and long-term (0-6 months) survival. Fifty-one patients were randomized to ATP and 48 to the control group. Results showed a significant favorable effect of ATP on triceps skin fold thickness [between-group difference per 8 weeks 1.76 mm, 95% confidence interval (CI): 0.48-3.12 mm; P = 0.009] and on short-term survival [0-8 weeks hazard ratio (HR): 0.40, 95% CI: 0.17-0.95; P = 0.037]. In weight-stable patients and in lung cancer patients, long-term survival (0-6 months) was also significantly better in ATP-treated patients (weight-stable patients HR: 0.40, 95% CI: 0.19-0.83; P = 0.014; patients with lung cancer: HR: 0.35, 95% CI: 0.14-0.88; P = 0.025). In conclusion, in this population of preterminal cancer patients, ATP infusions, at the dose and schedule studied, had a favorable effect on triceps skin fold thickness and survival, especially in weight-stable patients and patients with lung cancer. Larger studies are warranted to confirm these findings and to further define the effect of ATP on tumor growth and survival.

Goals of Work: In preterminal cancer patients, provision of palliative care in the patients' own environment is preferred. The aim of the present study was to evaluate patients' and caregivers' treatment adherence and patients' acceptance of home infusions with adenosine 5'-triphosphate (ATP)., Patients and Methods: Preterminal cancer patients (life expectancy <6 months) with mixed tumor types were eligible for the study. Patients received a maximum of eight weekly intravenous 8-10 h ATP infusions. Evaluation of treatment adherence was based on registration of protocol deviations and patients' acceptance by structured interviews with patients., Main Results: Fifty-one patients received a total of 266 intravenous ATP infusions. The infusion protocol was well executed: mean duration approximately 8.30 h, stepwise achievement of the maximum infusion rate within 30 min in 65% of the infusions, and almost no delay in weekly administration. All except one patient were not burdened by the administration of the infusions at home and none of them had felt afraid. The majority of patients found the advantages of the ATP infusions outweighing the disadvantages. However, an important bottleneck in the administration of ATP infusions at home was difficulty in establishing venous access., Conclusion: ATP infusions at home are well accepted by patients. Difficulties in establishing venous access might be reduced by composing specialized home infusion teams working both at the day care center and at home or by adopting an alternative route of venous access.

To obtain insight in mechanisms of action of extracellular adenosine triphosphate (ATP) and adenosine, a simple HPLC method has been optimized and applied to investigate ATP metabolism in human whole blood ex vivo. This method provided good chromatographic resolution and peak shape for all eight compounds within a 19 min run time. The baseline was clean, the lower limit of quantification was below 0.3 micromol/L for all adenine nucleotides and the method demonstrated good linearity. Within-day precision ranged from 0.7 to 5.9% and between-days from 2.6 to 15.3%. Simplicity and simultaneous detection of ATP and its metabolites make this method suitable for clinical pharmacokinetic studies.

Damage to healthy tissue is a major limitation of radiotherapy treatment of cancer patients, leading to several side effects and complications. Radiation-induced release of pro-inflammatory cytokines is thought to be partially responsible for the radiation-associated complications. The aim of the present study was to investigate the protective effects of extracellular ATP on markers of oxidative stress, radiation-induced inflammation and DNA damage in irradiated blood ex vivo. ATP inhibited radiation-induced TNF-alpha release and increased IL-10 release. The inhibitory effect of ATP on TNF- alpha release was completely reversed by adenosine 5'-O-thiomonophosphate, indicating a P2Y(11) mediated effect. Furthermore, ATP attenuated radiation-induced DNA damage immediate, 3 and 6h after irradiation. Our study indicates that ATP administration alleviates radiation-toxicity to blood cells, mainly by inhibiting radiation-induced inflammation and DNA damage.

We recently reported that adenosine 5'-triphosphate (ATP) modulates cytokine release in lipopolysaccharide (LPS)-phytohemagglutinin (PHA)-stimulated blood. ATP inhibited tumor necrosis factor-alpha (TNF-alpha) release via activation of the P2Y(11) receptor and increased interleukin (IL)-10 release via stimulation of the P2Y(12) receptor. Because ATP is known to be broken down by various ecto-enzymes, we determined the degradation profile of ATP in time in LPS-PHA-stimulated blood. ATP slowly metabolized with 14% remaining after 6h. Simultaneously, adenosine 5'-diphosphate (ADP), adenosine 5'-monophosphate (AMP) and hypoxanthine were formed. Subsequently, we investigated the time-dependent effects of ATP and its metabolites on inflammatory markers. Results showed that ATP decreased the rise in concentrations of TNF-alpha, interferon-gamma (IFN-gamma) and IL-1beta, but increased concentrations of IL-8 and IL-10. Metabolites of ATP showed either no, similar or opposite effects on cytokine release, compared to ATP. In conclusion, ATP has rapid immunomodulatory effects on a variety of cytokines in stimulated whole blood that persist until 24h.

The aim of the study was to investigate the safety of adenosine 5'-triphosphate (ATP) administration at home in pre-terminal cancer patients. Included were patients with cancer for whom medical treatment options were restricted to supportive care, who had a life expectancy of less than 6 months, a World Health Organization performance status 1 or 2, and suffered from at least one of the following complaints: fatigue, anorexia or weight loss >5% over the previous 6 months. Side effects were registered systematically on a standard form according to the National Cancer Institute (NCI) Common Toxicity Criteria. Fifty-one patients received a total of 266 intravenous ATP infusions. Of these, 11 infusions (4%) were given at the lowest dose of 20 microg kg(-1) min(-1), 85 infusions (32%) at 25-40 microg kg(-1) min(-1), and 170 (64%) at the highest dose of 45-50 microg kg(-1) min(-1) ATP. The majority of ATP infusions (63%) were without side effects. Dyspnea was the most common side effect (14% of infusions), followed by chest discomfort (12%) and the urge to take a deep breath (11%). No symptoms of cardiac ischemia occurred in any of the infusions. All side effects were transient and resolved within minutes after lowering the ATP infusion rate. Side effects were most frequent in the presence of cardiac disorders. We conclude that ATP at a maximum dose of 50 microg kg(-1) min(-1) can be safely administered in the home setting in patients with pre-terminal cancer.

Background: It is well-known that nonsteroidal anti-inflammatory drugs (NSAIDs) can cause damage to the small bowel associated with disruption of mucosal barrier function. In healthy human volunteers, we showed previously that topical administration of adenosine 5'-triphosphate (ATP) by naso-intestinal tube attenuated a rise in small intestinal permeability induced by short-term challenge with the NSAID indomethacin. This finding suggested that ATP may be involved in the preservation of intestinal barrier function. Our current objective was to corroborate the favourable effect of ATP on indomethacin-induced permeability changes in healthy human volunteers when ATP is administered via enteric-coated capsules, which is a more practically feasible mode of administration. Since ATP effects may have been partly mediated through its breakdown to adenosine, effects of encapsulated adenosine were tested also., Methods: By ingesting a test drink containing 5 g lactulose and 0.5 g L-rhamnose followed by five-hour collection of total urine, small intestinal permeability was assessed in 33 healthy human volunteers by measuring the urinary lactulose/rhamnose excretion ratio. Urinary excretion of lactulose and L-rhamnose was determined by fluorescent detection high-pressure liquid chromatography (HPLC). Basal permeability of the small intestine was assessed as a control condition (no indomethacin, no ATP/adenosine). As a model of increased small intestinal permeability, two dosages of indomethacin were ingested at 10 h (75 mg) and 1 h (50 mg) before ingesting the lactulose/rhamnose test drink. At 1.5 h before indomethacin ingestion, two dosages of placebo, ATP (2 g per dosage) or adenosine (1 g per dosage) were administered via enteric-coated hydroxypropyl methylcellulose (HPMC) capsules with Eudragit L30D-55., Results: Median urinary lactulose/rhamnose excretion ratio (g/g) in the control condition was 0.032 (interquartile range: 0.022-0.044). Compared to the control condition, lactulose/rhamnose ratio after ingestion of indomethacin plus placebo was significantly increased to 0.039 (0.035-0.068); P < 0.01). The indomethacin-induced increase was neither affected by administration of encapsulated ATP (0.047 (0.033-0.065)) nor adenosine (0.050 (0.030-0.067)). Differences in L/R ratios between the conditions with indomethacin plus placebo, ATP or adenosine were not significant., Conclusion: In this study, either ATP or adenosine administered via enteric-coated capsules had no effect on indomethacin-induced small intestinal permeability changes in healthy human volunteers. The observed lack of effect of encapsulated ATP/adenosine may have been caused by opening of the enteric-coated supplement at a site distal from the indomethacin-inflicted site. Further studies on site-specific effectiveness of ATP/adenosine on intestinal permeability changes are warranted.

Background: Nonsteroidal anti-inflammatory drug (NSAID) use is associated with an elevated risk of gastrointestinal damage. As adenosine 5'-triphosphate (ATP) may play a protective role in the small intestine, our objective was to determine the local effect of ATP on small intestinal permeability changes induced by short-term challenge of the NSAID indomethacin in healthy humans., Methods: Mucosal permeability of the small intestine was assessed by the lactulose/rhamnose permeability test, that is, ingestion of a test drink containing 5 g lactulose and 0.5 g L-rhamnose followed by total urine collection for 5 h. Urinary excretion of lactulose and L-rhamnose was determined by fluorescent detection high-pressure liquid chromatography (HPLC). Basal small intestinal permeability was assessed as a control condition. As a model of increased small intestinal permeability, two doses of indomethacin were ingested before ingestion of the test drink (75 mg and 50 mg at 10 h and 1 h before the test drink, respectively). Concomitantly with indomethacin ingestion, placebo or 30 mg/kg ATP was administered through a naso-intestinal tube., Results: Median urinary lactulose/rhamnose ratio (g/g) in the control condition was 0.023 (interquartile range: 0.013-0.041). Compared with the control condition, urinary lactulose/rhamnose ratio after ingestion of indomethacin and administration of placebo was significantly increased [0.042 (0.028-0.076); P<0.01]. In contrast, urinary lactulose/rhamnose ratio after indomethacin ingestion plus ATP administration [0.027 (0.020-0.046)] was significantly lower than the lactulose/rhamnose ratio in the placebo condition (P<0.01)., Conclusions: Topical ATP administration into the small intestine during short-term challenge of the NSAID indomethacin attenuates the NSAID-induced increase in small intestinal permeability in healthy humans.

Background: Palliative care in cancer aims at alleviating the suffering of patients. A previous study in patients with advanced non-small-cell lung cancer showed that adenosine 5'-triphosphate (ATP) infusions had a favourable effect on fatigue, appetite, body weight, muscle strength, functional status and quality of life. The present study was designed 1. To evaluate whether ATP has favourable effects in terminally ill cancer patients, 2. To evaluate whether ATP infusions may reduce family caregiver burden and reduce the use of professional health care services, and 3. To test the feasibility of application of ATP infusions in a home care setting., Methods/design: The study can be characterized as an open-labelled randomized controlled trial with two parallel groups. The intervention group received usual palliative care, two visits by an experienced dietician for advice, and regular ATP infusions over a period of 8 weeks. The control group received palliative care as usual and dietetic advice, but no ATP. This paper gives a description of the study design, selection of patients, interventions and outcome measures., Discussion: From April 2002 through October 2006, a total of 100 patients have been randomized. Follow-up of patients will be completed in December 2006. At the time of writing, five patients are still in follow up. Of the 95 patients who have completed the study, 69 (73%) have completed four weeks of follow-up, and 53 (56%) have completed the full eight-week study period. The first results are expected in 2007.

We recently showed that the physiological compound ATP simultaneously inhibited TNF-alpha and stimulated IL-10 release in LPS-PHA stimulated blood. The purpose of the present study was to determine the mechanism involved in the concerted modulatory effect of ATP on TNF-alpha and IL-10. Incubation of blood with ATP in the presence of selective P2 receptor antagonists showed that the stimulatory effect of ATP on IL-10 release was completely annihilated by both 2-MeSAMP (a P2Y12/13 receptor antagonist) and PSB-0413 (a P2Y12 receptor antagonist). On the other hand, the inhibitory effect of ATP on TNF-alpha release was completely reversed by 5'-AMPS (a P2Y11 receptor antagonist) as well as by H-89, an inhibitor of cAMP-activated PKA. The concerted inhibition by ATP of TNF-alpha release via P2Y11 activation and stimulation of IL-10 release via P2Y12 activation implicates a novel approach towards immunomodulation by altering the balance among pro- and anti-inflammatory cytokines.

We recently reported that Adenosine-5'-triphosphate (ATP) is able to inhibit the inflammatory reaction in stimulated whole blood. Many diseases, in which inflammatory reactions are involved, are associated with oxidative stress. In the present study, we therefore, investigated the effect of ATP on cytokine release in stimulated whole blood under conditions of oxidative stress, as simulated by pre-incubation of blood with hydrogen peroxide (H(2)O(2)). In the presence of H(2)O(2), ATP at concentrations of 100 and 300 microM inhibited Tumour Necrosis factor-alpha (TNF-alpha) release and stimulated IL-10 release in LPS-PHA stimulated whole blood. Moreover, electron spin resonance (ESR) measurements showed that ATP and its breakdown product Adenosine-5'-diphosphate (ADP) attenuated spin trap-hydroxyl radical adduct formation in the Fenton reaction. Our results demonstrate that even in circumstances of severe oxidative stress, ATP has marked anti-inflammatory properties in stimulated whole blood. Moreover, the inhibition of the hydroxyl radical ESR signal indicates a direct attenuation of oxidative stress by ATP.

In vitro studies suggest that extracellular nucleotides and nucleosides may be important regulators of inflammatory and immune responses. Most studies with adenosine 5'-triphosphate (ATP) have been performed in cell lines, which are remote from the human situation. The purpose of the present study was to determine the effects of ATP on TNF-alpha, IL-6 and IL-10 release in stimulated whole blood. Blood samples were drawn from healthy volunteers and incubated with ATP and lipopolysaccharide (LPS) + phytohemagglutinin (PHA) for 24 h. Contrary to expectations, ATP at 100 microM and 300 microM induced a reduction in TNF-alpha secretion by 32+/-8% (mean +/- SEM) and 65+/-4%, respectively. Furthermore, these ATP concentrations induced an increase in IL-10 secretion by 48+/-5% and 62+/-7% in whole blood. The ATP analogue adenosine 5'-O-(3-thiotriphosphate) (ATP-gamma-S) and adenosine 5'-diphosphate (ADP) also inhibited TNF-alpha release, but only ADP showed a stimulatory effect on IL-10. Co-treatment with adenosine deaminase did not reverse the ATP effect on TNF-alpha and IL-10. These results show, for the first time, that ATP inhibits the inflammatory response in stimulated whole blood as indicated by inhibition of TNF-alpha and stimulation of IL-10 release and that this effect is predominantly mediated by ATP and not by adenosine.

We recently reported that regular infusions of adenosine 5'-triphosphate (ATP) inhibited loss of body weight and quality of life in patients with non-small cell lung cancer (NSCLC). In the present paper we investigated whether ATP affects tumor growth and survival in the same group of patients. Fifty-eight NSCLC patients (stage IIIB or IV) were randomly assigned to receive either 10 i.v. 30-h ATP infusions every 2-4 weeks over a 24-week period (n = 28) or no ATP (control patients, n = 30). ATP was given for a median of 6.5 infusions. Differences in time to progression and survival between patients in both groups were tested by means of the log-rank test and Cox regression analysis. Forty-nine patients were evaluable for tumor response. None of the evaluable patients showed a complete or partial response. Median time to progression was 3.9 months [95% confidence interval (CI) = 2.3-5.5] in the ATP group compared to 3.0 months (95% CI = 2.4-3.7) in the control group (p = 0.71). Median survival was 5.6 months (95% CI = 1.1-10.1) for the ATP group and 4.7 months (95% CI = 2.6-6.8) for the control group (p = 0.68). ATP treatment was associated with a significant increase in survival in the subgroup of weight-losing patients with stage IIIB NSCLC: in this subgroup, median survival was 9.3 months (95% CI = 2.1-16.5) for ATP-treated patients versus 3.5 months (95% CI = 2.3-4.7) for control patients (between-group difference: p = 0.009). No significant effect of ATP was observed for weight-losing patients with stage IV NSCLC or for weight-stable NSCLC patients. Although ATP as a single therapy does not lead to tumor regression or increased survival in patients with advanced lung cancer, it may prolong survival in weight-losing patients with stage IIIB lung cancer. The latter finding is intriguing, but requires confirmation in larger clinical trials.

We recently observed inhibition of weight loss in patients with advanced nonsmall-cell lung cancer after intravenous infusion of ATP. Because liver ATP levels were found to be decreased in lung cancer patients with weight loss, the present 31P magnetic resonance spectroscopy (MRS) study was aimed at investigating whether ATP infusion restores liver energy status in these patients. Nine patients with advanced nonsmall-cell lung cancer (stage IIIB/IV) were studied 1 week before (baseline) and at 22 to 24 hours of continuous ATP infusion (37-75 microg/kg/min). Localized hepatic 31P MR spectra (repetition time 15 seconds), obtained in the overnight-fasted state, were analyzed for ATP and P(i) content. Ten healthy subjects (without ATP infusion) served as control. Liver ATP levels in lung cancer patients increased from 8.8 +/- 0.7% (relative to total MR-detectable phosphate; mean +/- SE) at baseline to 12.2 +/- 0.9% during ATP infusion (P <.05), i.e., a level similar to that in healthy subjects (11.9 +/- 0.9%). The increase in ATP level during ATP infusion was most prominent in patients with > or = 5% weight loss (baseline: 7.9 +/- 0.7%, during ATP infusion: 12.8 +/- 1.0%, P < 0.01). In conclusion, ATP infusion restores hepatic energy levels in patients with advanced lung cancer, especially in weight-losing patients. These changes may contribute to the previously reported beneficial effects of ATP infusion on the nutritional status of lung cancer patients.

Purpose: In a randomized clinical trial in patients with advanced non-small-cell lung cancer (NSCLC), infusion with adenosine 5'-triphosphate (ATP) inhibited loss of body weight and quality of life. In the present article, the effects of ATP on body composition, energy intake, and energy expenditure as secondary outcome measures in the same patients are reported., Patients and Methods: Patients with NSCLC, stage IIIB or IV, were randomized to receive either 10 intravenous, 30-hour ATP infusions every 2 to 4 weeks or no ATP. Fat mass (FM), fat-free mass (FFM), and arm muscle area were assessed at 4-week intervals for 28 weeks. Food intake, body cell mass (BCM), and resting energy expenditure (REE) were assessed at 8-week intervals for 16 weeks. Between-group differences were tested for statistical significance by repeated-measures analysis of covariance., Results: Fifty-eight patients were randomized (28 ATP, 30 control). No change in body composition over the 28-week follow-up period was found in the ATP group, whereas, per 4 weeks, the control group lost 0.6 kg of FM (P =.004), 0.5 kg of FFM (P =.02), 1.8% of arm muscle area (P =.02), and 0.6% of BCM/kg body weight (P =.054) and decreased 568 KJ/d in energy intake (P =.0001). Appetite also remained stable in the ATP group but decreased significantly in the control group (P =.0004). No significant differences in REE between the ATP and control groups were observed., Conclusion: The inhibition of weight loss by ATP infusions in patients with advanced NSCLC is attributed to counteracting the loss of both metabolically active and inactive tissues. These effects are partly ascribed to maintenance of energy intake.

Background: Nutritional supplements designed to increase adenosine 5?-triphosphate (ATP) concentrations are commonly used by athletes as ergogenic aids. ATP is the primary source of energy for the cells, and supplementation may enhance the ability to maintain high ATP turnover during high-intensity exercise. Oral ATP supplements have beneficial effects in some but not all studies examining physical performance. One of the remaining questions is whether orally administered ATP is bioavailable. We investigated whether acute supplementation with oral ATP administered as enteric-coated pellets led to increased concentrations of ATP or its metabolites in the circulation. Methods: Eight healthy volunteers participated in a cross-over study. Participants were given in random order single doses of 5000 mg ATP or placebo. To prevent degradation of ATP in the acidic environment of the stomach, the supplement was administered via two types of pH-sensitive, enteric-coated pellets (targeted at release in the proximal or distal small intestine), or via a naso-duodenal tube. Blood ATP and metabolite concentrations were monitored by HPLC for 4.5 h (naso-duodenal tube) or 7 h (pellets) post-administration. Areas under the concentration vs. time curve were calculated and compared by paired-samples t-tests. Results: ATP concentrations in blood did not increase after ATP supplementation via enteric-coated pellets or naso-duodenal tube. In contrast, concentrations of the final catabolic product of ATP, uric acid, were significantly increased compared to placebo by ~50% after administration via proximal-release pellets (P = 0.003) and naso-duodenal tube (P = 0.001), but not after administration via distal-release pellets. Conclusions: A single dose of orally administered ATP is not bioavailable, and this may explain why several studies did not find ergogenic effects of oral ATP supplementation. On the other hand, increases in uric acid after release of ATP in the proximal part of the small intestine suggest that ATP or one of its metabolites is absorbed and metabolized. Uric acid itself may have ergogenic effects, but this needs further study. Also, more studies are needed to determine whether chronic administration of ATP will enhance its oral bioavailability. [ABSTRACT FROM AUTHOR]

Background: Extracellular adenosine 5'-triphosphate (ATP) is involved in the regulation of a variety of biologic processes, including neurotransmission, muscle contraction, and liver glucose metabolism, via purinergic receptors. In nonrandomized studies involving patients with different tumor types including non-small-cell lung cancer (NSCLC), ATP infusion appeared to inhibit loss of weight and deterioration of quality of life (QOL) and performance status. We conducted a randomized clinical trial to evaluate the effects of ATP in patients with advanced NSCLC (stage IIIB or IV).Methods: Fifty-eight patients were randomly assigned to receive either 10 intravenous 30-hour ATP infusions, with the infusions given at 2- to 4-week intervals, or no ATP. Outcome parameters were assessed every 4 weeks until 28 weeks. Between-group differences were tested for statistical significance by use of repeated-measures analysis, and reported P values are two-sided.Results: Twenty-eight patients were allocated to receive ATP treatment and 30 received no ATP. Mean weight changes per 4-week period were -1.0 kg (95% confidence interval [CI] = -1.5 to -0.5) in the control group and 0.2 kg (95% CI = -0.2 to +0.6) in the ATP group (P =.002). Serum albumin concentration declined by -1.2 g/L (95% CI= -2.0 to -0.4) per 4 weeks in the control group but remained stable (0.0 g/L; 95% CI = -0.3 to +0.3) in the ATP group (P =.006). Elbow flexor muscle strength declined by -5.5% (95% CI = -9.6% to -1. 4%) per 4 weeks in the control group but remained stable (0.0%; 95% CI= -1.4% to +1.4%) in the ATP group (P =.01). A similar pattern was observed for knee extensor muscles (P =.02). The effects of ATP on body weight, muscle strength, and albumin concentration were especially marked in cachectic patients (P =.0002, P =.0001, and P =. 0001, respectively, for ATP versus no ATP). QOL score changes per 4-week period in the ATP group showed overall less deterioration than in the control group-physical scores (-0.2% versus -2.4%; P =. 0002); functional scores (+0.4% versus -5.5%; P =.02); psychologic scores (-0.7% versus -2.4%; P =.11); overall QOL score (+0.1% versus -3.5%; P =.0001).Conclusions: This randomized trial demonstrates that ATP has beneficial effects on weight, muscle strength, and QOL in patients with advanced NSCLC. [ABSTRACT FROM AUTHOR]

The article discusses a case of reduced disease activity and inflammation in a 50-year-old female patient with active rheumatoid arthritis following infusions with adenosine 5-triphosphate (ATP). The dosage of the methotrexate (MTX) being received by the patient for RA was reduced due to gastrointestinal side effects at higher doses. The patient showed improved disease activity after treatment with ATP was initiated.