Influence of chronic ethanol consumption on the inositol phospholipid fatty acid composition of human peripheral blood lymphocytes

Defective calcium increase and inositol phosphate production in anti-CD3-stimulated lymphocytes of alcoholics without progressive liver disease

Intracellular free calcium concentration, phosphoinositide turnover, and inositol phosphate production were analyzed in peripheral blood lymphocytes from seven well-nourished alcoholic patients without severe acute or chronic liver disease, before and after stimulation with anti-CD3 antibody. Seven comparable nondrinkers were studied as controls. A lower increase in intracellular free calcium concentration was detected in alcoholics, after anti-CD3 stimulation of lymphocytes, than in control subjects. Lymphocyte activation generated inositol phosphates in both controls and alcoholics, but inositol phosphate production was significantly lower in alcoholics. The agreement between these findings indicates that the reduction in inositol phosphates is one of the most important events in the early phases of lymphocyte activation in alcoholics.

Alcohol use and T-lymphocyte subsets among injection drug users with HIV-1 infection: a prospective analysis

OBJECTIVES

Alcohol use is known to alter immune function and has immunosuppressive effects that may modify T-lymphocyte subpopulations. However, there is no clear evidence regarding the relationship of alcohol use with the progression of immunodeficiency in human immunodeficiency virus-type 1 (HIV-1)-seropositive individuals, particularly injection drug users (IDUs).

METHODS

Using prospective data from a cohort of IDUs in a study of the natural history of HIV infection, we examined the relationship of alcohol use and changes in T-lymphocyte subsets. Among the 2921 IDUs followed semiannually in outpatient clinics, 188 were documented HIV-1 seroconverters with known time of seroconversion. At each visit, all study participants were interviewed, underwent physical examinations, and had blood drawn for laboratory studies. Alcohol use was measured by reported frequency and quantity of alcoholic beverages. Longitudinal analyses included data for up to 5 years postseroconversion. To formally test the association of alcohol use with change in levels of CD4+ and CD8+ cells subsequent to HIV seroconversion, regression models incorporating autocorrelation structure were applied.

RESULTS

Alcohol use was not appreciably related to age, gender, marital status, income, education, or the duration of intravenous drug use. CD4% decreased for all IDUs within the first 5 years after seroconversion, with no significant differences between alcohol categories. CD8% increased for all IDUs, with no significant differences by alcohol category within the first 2 years after seroconversion. However, between 2 to 5 years postseroconversion, there was a statistically significant increase among the heaviest drinkers: CD8% increased 6.9%/year [95% confidence interval (CI): 4.7, 8.0] for the IDUs who reported > 21 drinks/week, 2.4%/year (95% CI: 0.8, 4.0) for IDUs who drank 21 drinks/week or less, and 0.4% (95% CI: -2.1, 2.9) for abstainers. Similar results were obtained for CD4 and CD8 absolute counts.

CONCLUSIONS

In this study population of IDUs, CD8% (but not CD4%) is associated with alcohol consumption early after HIV seroconversion. This is the first prospective study to date to assess the relationship of alcohol use with HIV progression from the time of HIV seroconversion among a cohort of IDUs. If confirmed in future investigations, the findings may have significant implications for prevention and early intervention programs aimed at inhibiting disease progression among HIV-positive IDUs.

Phosphatidylinositol metabolism in lymphocytes of chronic alcoholic patients after anti-CD3 stimulation

The immunological alterations observed in chronic alcoholic patients may be due to alterations of signal transduction across the lymphocyte membrane. Upon binding of mitogens or antigens to specific plasma membrane receptors, the activation of phospholipase C leads to the hydrolysis of inositol phospholipids, producing inositol phosphates and diacylglycerol. One of the early events in lymphocyte activation is an increase of intracellular calcium concentration, due to both an influx from extracellular fluid and a release from intracellular stores mediated by inositol phosphates. In this study we verified whether the diminished mobilization of intracellular calcium, previously observed in alcoholics, is caused by alteration in phosphoinositide turnover. We evaluated total inositol phosphate production in peripheral blood lymphocytes after anti-CD3 stimulation, comparing control subjects and alcoholic patients. Lymphocyte activation generated inositol phosphates in both controls and alcoholics, but to a different extent, inositol phosphate production being significantly higher in controls than in alcoholics. This reduction in inositol phosphate production could be accounted either to an inhibition of PLC activity or to a modified affinity of phospholipase C for its own substrates, i.e., phosphoinositides, which fatty acid composition has been previously demonstrated to be greatly different in alcoholics in comparison to healthy subjects.

In vivo effect of chronic ethanol consumption on the fatty acid composition of phosphatidylinositols in resting and anti-CD3-activated lymphocytes

Fatty acid composition of phosphatidylinositols was analyzed in peripheral blood lymphocytes from nine alcoholic patients who were well nourished and without severe acute and chronic liver disease, before and after stimulation with anti-CD3 antibody. Six comparable nondrinkers were studied as controls. A reduction in unsaturated fatty acid (mainly arachidonic) and an increase in palmitic and stearic acid molar content were observed in phosphatidylinositol (PI), phosphatidylinositol-4-phosphate (PIP), and phosphatidylinositol-4,5-bisphosphate (PIP2) in unstimulated samples from alcoholic patients in comparison with normal subjects, leading to a significant decrease in the saturated/unsaturated ratio. In controls, anti-CD3 stimulation caused a marked decrease in arachidonic acid relative molar content counterbalanced by an increase in other polyunsaturated fatty acid relative molar content in PI, PIP, and PIP2 fractions. Interestingly, after anti-CD3 stimulation, alcoholic patients show the same trend of modification in the fatty acid composition resulting in a sharp reduction of arachidonic acid relative molar content. These results support the hypothesis of an alteration in nutrients being responsible for immune derangement in alcoholics.