Metabolic Messengers: itaconate.

The metabolite itaconate has emerged as an important immunoregulator with roles in antibacterial defence, inhibition of inflammation and, more recently, as an inhibitory factor in obesity. Itaconate is one of the most upregulated metabolites in inflammatory macrophages. It is produced owing to the disturbance of the tricarboxylic acid cycle and the diversion of aconitate to itaconate via the enzyme aconitate decarboxylase 1. In immunology, initial studies concentrated on the role of itaconate in inflammatory macrophages where it was shown to be inhibitory, but this has expanded as the impact of itaconate on other cell types is starting to emerge. This review focuses on itaconate as a key immunoregulatory metabolite and describes its diverse mechanisms of action and its many impacts on the immune and inflammatory responses and in cancer. We also examine the clinical relevance of this immunometabolite and its therapeutic potential for immune and inflammatory diseases.

Refining the treatment of women with unstable angina--a randomized, double-blind, comparative safety and efficacy evaluation of Integrelin versus aspirin in the management of unstable angina.

BACKGROUND: Although women typically develop coronary artery disease several years after men, once they have symptomatic disease their thromboembolic complications are worse than in men. The mechanism mediating this gender difference in outcome after thromboembolic events is unknown. We previously studied platelet functions in siblings from patients with premature coronary artery disease. We observed that platelets from women are responsive than their male counterparts. In particular, platelets from women stimulated ex vivo with various agonists bind more fibrinogen molecules than platelets from men. HYPOTHESIS: We hypothesized that in patients with acute coronary events, the control of platelet activity might require stronger antagonists in women than in men. METHODS: To test this hypothesis, we investigated retrospectively the results of a trial on Integrelin in unstable angina. RESULTS: We report that platelet aggregation and Holter-detected ischemic episodes are significantly reduced in women with unstable angina treated with the specific GPIIb-IIIa inhibitor, Integrelin, compared with the standard platelet inhibitor aspirin. In contrast, both platelet aggregation and Holter-detected ischemic events are well controlled in men with unstable angina treated with standard therapy including aspirin. CONCLUSION: Integrelin does provide protection in men, but, in contrast with women, not beyond what can be achieved with aspirin. Our data are consistent with the concept that the platelets from women require stronger and more specific inhibitors to limit their activity, and that platelets may play a more important role in women with acute coronary syndromes than in men. Most important, specific GPIIb-IIIa inhibitors may represent a therapeutic option which provides as much suppression of ischemic events in women as they do in men with coronary artery disease.

Early treatment of stroke with monosialoganglioside GM-1. Efficacy and safety results of the Early Stroke Trial.

BACKGROUND AND PURPOSE: The Early Stroke Trial (EST) is a randomized, double-blind, placebo-controlled trial to assess the effect of monosialoganglioside GM-1 in improving recovery in patients who experienced an ischemic supratentorial stroke. METHODS: Sixteen clinical centers recruited 805 patients, of whom 792 were confirmed to be eligible. Treatment, consisting of a first dose of either 200 mg GM-1 or placebo, was initiated within 5 hours of the onset of stroke; a second dose of either 100 mg GM-1 or placebo was administered 12 hours later. Thereafter, patients received a daily injection of 100 mg GM-1 or placebo intravenously from day 2 through 10 and intramuscularly from day 11 through 21. Patients were followed up for a total of 4 months. RESULTS: Survival was similar in the two treatment groups. Improvement in neurological status, as measured by the change in Canadian Neurological Scale score between baseline and 4-month assessments, was greater in the group receiving GM-1; the observed difference between treatment groups was 0.22 (P = .06). A post hoc analysis in the subgroup of patients treated within 4 hours showed a statistically significant difference, with Canadian Neurological Scale mean improvement of 0.41 (P = .016). GM-1 use was not associated with differences in frequency, nature, or severity of adverse experiences. CONCLUSIONS: These findings suggest that GM-1 is safe in the dose and treatment schedule used and that its efficacy in ischemic stroke is greater when given soon after onset of stroke.

Past and current clinical studies with GM-1 ganglioside in acute spinal cord injury.

Two recent prospective, randomized, placebo-controlled, double-blinded clinical drug studies in acute spinal cord injury have reported enhancement of neurologic recovery of motor function. The drugs investigated in these studies were methylprednisolone and GM-1 ganglioside. Before these studies, the treatment of patients with spinal cord injuries had been restricted to prevention of further injury to the spinal cord, limiting secondary damage following the initial injury, increasing the patient's ability to function through intensive rehabilitation, and facilitating any spontaneous recovery of neurologic function. Methylprednisolone is a steroid administered at very high levels, and GM-1 is a complex acidic glycolipid found at high levels in cell membranes in the mammalian central nervous system with known neuroprotective and neurofunctional restoration potential. This article summarizes the previously reported Maryland GM-1 clinical trial and presents the clinical and statistical design of a larger clinical trial being conducted with the purpose of verifying a beneficial GM-1 drug effect when administered with methylprednisolone in acute spinal cord injury.

GM-1 ganglioside in human spinal cord injury.

Spinal cord injury is typically a devastating injury with no or only limited neurologic recovery. Recent papers have reported enhancement of neurologic recovery following spinal cord injury with both methylprednisolone and GM-1 ganglioside. This paper provides additional details of the GM-1 study and a further analysis of recovery of motor function for each of the ten neurologic levels assessed in the study. This additional analysis provides further evidence that the largest enhanced recovery of motor function in the GM-1 treatment group occurred in the muscles of the lower extremities and is consistent with the enhanced recovery occurring in the white matter tracts passing through the level of injury.

Design and baseline results of the monosialoganglioside early stroke trial. The EST Study Group.

BACKGROUND AND PURPOSE: The Early Stroke Trial is a randomized, placebo-controlled, double-masked, multicenter study to assess the safety and efficacy of monosialoganglioside in patients who have suffered an ischemic stroke of the cerebral hemispheres. METHODS: Only patients who could be evaluated and treated within 5 hours after the onset of stroke were considered; within each center, subjects were stratified by age, sex, and clinical severity. Patients were randomly allocated to receive a specified sequence of intravenous and intramuscular doses of either monosialoganglioside or identical-appearing placebo for 21 days. Patients were followed up for 4 months after randomization. Neurological status was measured primarily by using the Canadian Neurological Scale. After assessing the effect of treatment on survival, the principal measure of efficacy will be the change in neurological status between baseline and the 4-month follow-up among survivors. RESULTS: Sixteen clinical centers, 15 in Europe and one in North America, entered a total of 792 eligible patients during a 36-month recruitment period (from May 1987 to April 1990). In our series there were more men than women, and the relative frequency of patients increased with advancing age. The most frequently associated cardiovascular conditions were hypertension, atrial fibrillation, and peripheral vascular disease. Approximately 46% of the patients were admitted to a hospital within 1 hour and 81%, within 2 hours after the onset of stroke. About 22% first received the study treatment within 3 hours and 57%, within 4 hours. CONCLUSIONS: This study demonstrates the feasibility of large-scale trials with the onset of treatment within 5 hours after an ischemic stroke.

GM-1 ganglioside in human spinal cord injury.

Spinal cord injury is typically a devastating injury with no or only limited neurologic recovery. Recent papers have reported enhancement of neurologic recovery following spinal cord injury with both methylprednisolone and GM-1 ganglioside. This paper provides additional details of the GM-1 study and a further analysis of recovery of motor function for each of the ten neurologic levels assessed in the study. This additional analysis provides further evidence that the largest enhanced recovery of motor function in the GM-1 treatment group occurred in the muscles of the lower extremities and is consistent with the enhanced recovery occurring in the white matter tracts passing through the level of injury.

Chagas' cardioneuropathy: effect of ganglioside treatment in chronic dysautonomic patients--a randomized, double-blind, parallel, placebo-controlled study.

To date, there is no effective pharmacologic treatment for Chagas' cardioneuropathy, one of the most common causes of congestive heart failure and sudden death in the world. Fifty-eight adults with positive serology for Chagas' disease and abnormal autonomic nervous system tests participated in this placebo-controlled clinical trial with Cronassial (mixed gangliosides), 40 mg daily intramuscular injection for 4 or 8 weeks. We measured postural response (heart rate, systolic and diastolic arterial blood pressure changes in response to standing); heart rate changes induced by cough and hyperventilation reflex tests; dizziness on standing; number of stress-induced arrhythmias; and periodic acid-Schiff (PAS)-positive T-lymphocyte percentage in blood samples. Cronassial is safe and significantly improves systolic blood pressure (p = 0.050) and double product responses to postural stress (p = 0.028), hyperventilation heart rate response (p = 0.007), frequency of dizziness episodes (p less than 0.001), number of arrhythmias (p = 0.033), and percentage of PAS-positive T-lymphocyte counts (p less than 0.001) compared with placebo.

Recovery of motor function after spinal-cord injury--a randomized, placebo-controlled trial with GM-1 ganglioside.

BACKGROUND: Spinal-cord injury is devastating; until recently, there was no medical treatment to improve recovery of the initial neurologic deficit. Studies in animals have shown that monosialotetrahexosylganglioside (GM-1) ganglioside enhances the functional recovery of damaged neurons. METHODS: A prospective, randomized, placebo-controlled, double-blind trial of GM-1 ganglioside was conducted in patients with spinal-cord injuries. Of 37 patients entered into the study, 34 (23 with cervical injuries and 11 with thoracic injuries) completed the test-drug protocol (100 mg of GM-1 sodium salt or placebo intravenously per day for 18 to 32 doses, with the first dose taken within 72 hours of the injury) and a one-year follow-up period. Neurologic recovery was assessed with the Frankel scale (comprising five categories) and the American Spinal Injury Association (ASIA) motor score (a scale of scores from 0 to 100, derived from strength tests of 20 specific muscles, each scored from 0 to 5). RESULTS: There was a significant difference between groups in the distribution of improvement of Frankel grades from base line to the one-year follow-up (improvement of 0, 1, 2, and 3 grades in 13, 4, 1, and 0 patients, respectively, in the placebo group and 8, 1, 6, and 1 patients, respectively, in the GM-1 group; P = 0.034 by the Cochran-Mantel-Haenszel chi-square test). The GM-1-treated patients also had a significantly greater mean improvement in ASIA motor score from base line to the one-year follow-up than the placebo-treated patients (36.9 vs. 21.6 points; P = 0.047 by analysis of covariance with the base-line ASIA motor score as the covariate). An analysis of individual muscle recoveries revealed that the increased recovery in the GM-1 group was attributable to initially paralyzed muscles that regained useful motor strength rather than to strengthening of paretic muscles. CONCLUSIONS: This small study provides evidence that GM-1 enhances the recovery of neurologic function after one year. A larger study must be conducted, however, before GM-1 is considered efficacious and safe in treating spinal-cord injury.

GM1 gangliosides in the treatment of spinal cord injury: report of preliminary data analysis.

A prospective, randomized, placebo-controlled, double-blinded spinal cord injury GM1 ganglioside drug trial was completed. Of the 37 patients entered over a 16 month period, 34 patients (23 cervical and 11 thoracic injuries) received the test drug protocol and completed the one year follow up period. The neurologic recovery was quantified by serial measurement of the ASIA motor score throughout the acute hospital course and one year long follow up period. The primary variable used to assess neurologic recovery was the difference in the ASIA motor score from the admission value to the value at one year. The GM1 group had an average motor recovery of 36.9 points whereas the placebo group had an average change of 21.6 points (t-test difference, p = 0.088). Analysis of the secondary variable, the area under the ASIA motor score versus the logarithm of time, and the use of rank order nonparametric statistic on both the primary and secondary variables to sort neurologic recovery obtained similar statistical differences between the GM1 and placebo treatment groups. Randomization imbalances in baseline severity of injury and division of cervical and thoracic injury occurred in the trial. Because of this fact and the small sample size of the study verification of these results by a larger study is required.

Ganglioside administration in retinitis pigmentosa.

The retinitis pigmentosa process typically causes variably progressive visual loss due to retinal photoreceptor and pigment epithelial cell deterioration. No effective agent either to retard or stop the deterioration has been known. Because gangliosides have been shown to have a variety of trophic effects on peripheral nervous tissue, we administered a daily 40 mg intramuscular dose in a prospective, double-blind, randomized, placebo-controlled trial in 30 persons with retinitis pigmentosa with or without congenital deafness. When we compared baseline performance on the two principal study outcomes, visual field area and electroretinographic response amplitudes, there was a marginally statistically significant increase in visual field area in the ganglioside-treated group. The subgroup of subjects who had recordable electroretinograms at baseline and who received the drug showed in three of five cases an increase in amplitude to all stimuli. These results appear encouraging; however, the data must be interpreted cautiously because the numbers of individuals are very small. Further study of the possible benefits of ganglioside administration to retinitis pigmentosa patients appears warranted.

Cerebral arterial spasm--a controlled trial of nimodipine in patients with subarachnoid hemorrhage.

We enrolled 125 neurologically normal patients with intracranial aneurysms in a multi-institution, prospective, double-blind, randomized, placebo-controlled trial within 96 hours of their subarachnoid hemorrhage, to determine whether treatment with the calcium blocker nimodipine would prevent or reduce the severity of ischemic neurologic deficits from arterial spasm. A deficit from cerebral arterial spasm that persisted and was severe or caused death by the end of the 21-day treatment period occurred in 8 of 60 patients given placebo and in 1 of 56 given nimodipine (P = 0.03, Fisher's exact test). Analysis of the amount of basal subarachnoid blood on pre-entry CAT scans in patients with deficits from spasm showed that an increase in subarachnoid blood was not associated with a worse neurologic outcome among patients who received nimodipine, unlike the situation in patients given a placebo. There were no side effects from nimodipine. We conclude that nimodipine should be given to patients who are neurologically normal after subarachnoid hemorrhage in order to reduce the occurrence of severe neurologic deficits due to cerebral arterial spasm.

HL-A-linked human immune-response genes.

Genetic control of the response to specific natural-product antigens has been documented in three informative families. Families were selected on the basis of probands with tuberculosarcoidosis, chronic cutaneous moniliasis, and rheumatoid arthritis. An increased incidence of delayed cutaneous unresponsiveness was observed in each family. Positive associations were identified between HL-A haplotypes and immediate cutaneous hypersensitivity responses to 5, 8, and 11 of 23 test antigens in the three respective families. HL-A-associated differences in averaged responses of cutaneous hypersensitivity were excluded. These significant associations are consistent with linkage between HL-A haplotypes and genes responsible for the immune response to various natural-product antigens.