Insulin sensitivity in alcoholics in a withdrawal state

Alcohol protracted withdrawal syndrome: the role of anhedonia

AIMS

The aim of the present study is to characterize the relevance of withdrawal symptoms during the first 12 months of abstinence and their relation to anhedonia and craving.

METHODS

102 detoxified subjects meeting clinical criteria for Alcohol Dependence in Remission were recruited at various time since the detoxification and subdivided into four groups according to the length of abstinence (group 1: 15-30 days; group 2: 30-90 days; group 3: 90-180 days; group 4: 180-360). Withdrawal symptomatology was assessed through the Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar). The Visual Analogue Scale (VAS) for craving, the Snaith-Hamilton Pleasure Scale (SHAPS) and the Subscale for Anhedonia in the Scale for the Assessment of Negative Symptoms (SANSanh) where the other instruments employed.

RESULTS

Both anhedonia and withdrawal symptoms were identified in all the groups considered. SHAPS score and VAS for craving showed a significant difference between group 1 and groups 2, 3, and 4. As to CIWA-Ar items, apart from "orientation/clouding of sensorium" that was higher in groups 3 and 4 with respect to both groups 1 and 2, withdrawal symptoms were not significantly different between the periods considered. SHAPS and SANSanh were positively correlated to CIWA-Ar total score, "nausea and vomiting," and "headache/fullness in head."

DISCUSSION

The results of this study suggest the relevance of protracted withdrawal well beyond the limited period following the abrupt cessation of alcohol intake. The clinical dimension of anhedonia cannot be separated from the other behavioral symptoms of withdrawal and should be considered as part of the same process.

The effects of n-3 polyunsaturated fatty acids by gavage on some metabolic enzymes of rat liver

In this experimental study, the effect of fish n-3 fatty acids was studied on the some important enzymes of carbohydrate metabolism, hexokinase (HK), glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), lactate dehydrogenase (LDH), and malate dehydrogenase (MDH) in rat liver. Wistar albino rats of experimental group (n= 9) were supplemented fish omega-3 fatty acids (n-3 PUFA) as 0.4 g/kg bw. by gavage for 30 days in addition to their normal diet. Isotonic solution was given to the control group (n= 8) by the same way. At 30th day, the rats were killed by decapitation under ether anesthesia, autopsied and liver was removed. Spectrophotometric methods were used to determine the activities of above-mentioned enzymes in the liver. The n-3 PUFA caused increases in the activities of HK, G6PD, LDH, and MDH in comparison with control. These increases were statistically significant (P < 0.01) except 6PGD activity. As a result, n-3 PUFA may regulate the metabolic function of liver effectively by increasing HK, G6PD, 6PGD, LDH, and MDH enzyme activities of rat liver when added in enough amounts to the regular diet.

Metabolic effects of alcohol on skeletal muscle

The purpose of this review is to summarize our current understanding of the acute and chronic interactions between alcohol and nutrient metabolism in skeletal muscle. Insulin is well known to play an important regulatory role in nutrient, especially glucose, uptake and utilization in skeletal muscle. Several studies have shown that alcohol can acutely reduce the normal metabolic responses of skeletal muscle to the action of insulin. The most obvious of these is an acute impairment in glucose metabolism associated with alcohol consumption. While the exact mechanism(s) underlying this acute insulin resistance is presently unclear, several possible factors are discussed in this review. In contrast to these short-term effects, the effects of alcohol on skeletal muscle insulin sensitivity in chronic alcohol abusers are not as well established. Chronic alcohol abuse is known to be associated with skeletal myopathies, believed to result from alcohol induced abnormalities in muscle protein synthesis. Finally, the alcohol-mediated impairments of many aspects of skeletal muscle metabolism are discussed in relation to the insulin resistance associated broad spectrum of common lifestyle-related disorders, including non-insulin dependent diabetes mellitus and obesity, the consequences of which may be important to the pathogenesis of alcohol-related diseases.

Glucose metabolism, insulin-like growth factor-I, and insulin-like growth factor-binding protein-1 after alcohol withdrawal

Alcohol abusers often present with deteriorated glucose metabolism and insulin resistance. Changes in other glucoregulators, such as insulin-like growth factor-I (IGF-I) and IGF-binding protein-1 (IGFBP-1) may also be related to alcohol abuse. We studied the effects of alcohol withdrawal on blood glucose, serum insulin and C-peptide, and plasma IGF-I and IGFBP-1 levels in 27 noncirrhotic male alcoholics aged 43 +/- 9.0 (mean +/- SD) years on four consecutive days immediately after withdrawal. A 4-day monitoring period was conducted in four healthy nonalcoholic control men. The groups were similar in age and body mass index. Glucose, insulin, IGF-I, and IGFBP-1 did not differ significantly between the groups at the baseline, but C-peptide was higher in alcoholics (p < 0.01). After alcohol withdrawal, serum insulin and C-peptide levels increased in close correlation with each other (r = 0.82, p < 0.001). During the 4-day observation period in alcoholics, IGFBP-1 levels declined by 59%, whereas IGF-I increased by 41% (p < 0.001 for both comparisons). The change in insulin correlated inversely with the change in IGFBP-1 levels (r = -0.39, p < 0.05). In the control group, glucose, insulin, IGF-I, and IGFBP-1 remained unchanged during the 4-day monitoring period, whereas some reduction was observed in C-peptide. In conclusion, alcohol withdrawal enhances insulin production, as seen in increased C-peptide levels. An inverse correlation between the changes in insulin and that in IGFBP-1 might suggest that inhibition of IGFBP-1 by insulin remains largely unchanged during the acute phase of alcohol withdrawal.

Abstinent alcoholics exhibit an exaggerated stress response to 2-deoxy-D-glucose challenge

Chronic excessive alcohol consumption can significantly disturb the hypothalamic control of glucose metabolism; however, the mechanism and clinical significance of this disturbance are poorly understood. We used 2-deoxy-D-glucose (2-DG), which produces intracellular glucoprivation, to compare neurochemical, physiological, and behavioral responses to glucoprivic stress between alcoholics abstinent for 3 weeks and healthy volunteers. Twenty-six male alcoholics and 15 male healthy volunteers received intravenous infusions of placebo, 12.5 mg/kg, and 25.0 mg/kg of body weight of 2-DG over 30 min on three separate days, following a random-ordered, double-blind procedure. Minimal effects were observed following administration of the 12.5 mg/kg of body weight dose of 2-DG. Following 25.0 mg/kg, alcoholics showed both exaggerated ACTH and cortisol responses and greater increases in caloric intake when compared with controls. Although anxiety, desire to consume alcohol, plasma progesterone, and sympathetic and adrenal medullary activity all increased following 2-DG, these responses did not differ between alcoholics and controls. The present findings suggest certain specificity for the exaggerated hypothalamic and adrenocortical responses to mild glucoprivic stress in 3-week-abstinent alcoholics.

Leucine and glucose turnover in chronic alcoholics during early abstinence and after an ethanol load

We studied leucine turnover using a primed infusion of [1-14C]-L-leucine and glucose turnover using a primed infusion of [6-3H]-D-glucose in five alcoholic patients without liver damage and five age-matched controls. Infusions were maintained for 6 hr, and at the end of the 3rd hour, a 0.8 g/kg iv ethanol load was administered in 20 min. Leucine flux, nonoxidative disposal and oxidation rates, and glucose rate of appearance were calculated during the 3rd and 6th hours of infusion. Ethanol disappearance rate and the percentage completely metabolized to CO2 and H2O in 3 hr were also calculated. Compared with controls, alcoholics had significantly higher basal leucine flux (55.6 +/- 12 vs. 37.3 +/- 9.3 microM/m2/min) and nonoxidative disposal (48.7 +/- 8.7 vs. 31.1 +/- 7.5 microM/m2/min). No differences were observed in basal glucose appearance rates in alcoholics and controls (397.6 +/- 115.2 vs. 349.4 +/- 120.6 microM/m2/min). Compared with controls, alcoholics had a higher alcohol disappearance rate (2.72 +/- 0.59 vs. 1.84 +/- 0.43 mM/kg/min) and percentage of ethanol metabolized to CO2 and H2O in 3 hr (40.6 +/- 10.2 vs. 22.9 +/- 6.9%). After the ethanol load, both leucine turnover and glucose rate of appearance decreased significantly only in alcoholics. There was a positive correlation between the change in leucine flux and ethanol disappearance rate and percentage metabolized to CO2 and H2O in alcoholics.