Altered ultrastructure of lactating rat mammary epithelial cells induced by chronic ethanol ingestion

Dissecting the Role of Disturbed ER-Golgi Trafficking in Antivirals and Alcohol Abuse-Induced Pathogenesis of Liver Disorders

Antiviral drugs and alcohol abuse-induced organelle stresses have been linked to many disorders and the underlying molecular mechanisms are under intense investigations. This brief review communicates emerging evidence and research trends on how certain antivirals and alcohol affect ER-Golgi trafficking, which potentially impacts the function and integrity of the Golgi apparatus contributing to endoplasmic reticulum stress and cellular injury.

Advances and New Concepts in Alcohol-Induced Organelle Stress, Unfolded Protein Responses and Organ Damage

Alcohol is a simple and consumable biomolecule yet its excessive consumption disturbs numerous biological pathways damaging nearly all organs of the human body. One of the essential biological processes affected by the harmful effects of alcohol is proteostasis, which regulates the balance between biogenesis and turnover of proteins within and outside the cell. A significant amount of published evidence indicates that alcohol and its metabolites directly or indirectly interfere with protein homeostasis in the endoplasmic reticulum (ER) causing an accumulation of unfolded or misfolded proteins, which triggers the unfolded protein response (UPR) leading to either restoration of homeostasis or cell death, inflammation and other pathologies under severe and chronic alcohol conditions. The UPR senses the abnormal protein accumulation and activates transcription factors that regulate nuclear transcription of genes related to ER function. Similarly, this kind of protein stress response can occur in other cellular organelles, which is an evolving field of interest. Here, I review recent advances in the alcohol-induced ER stress response as well as discuss new concepts on alcohol-induced mitochondrial, Golgi and lysosomal stress responses and injuries.

Nursing from an ethanol-intoxicated dam induces short- and long-term disruptions in motor performance and enhances later self-administration of the drug

RATIONALE

During interactions with an ethanol-intoxicated dam, preweanling rats encode ethanol-related chemosensory information. These experiences have been observed to enhance subsequent recognition of ethanol's chemosensory properties and to modulate learning about ethanol.

OBJECTIVE

The present study tested the effects of ethanol-related nursing experiences on motor function in later infancy and adolescence and on ethanol intake during adolescence.

METHODS

Wistar-derived rats were reared by dams intragastrically administered with ethanol (2.5 g/kg) or with water during postnatal days (PDs) 3, 5, 7, 9, 11, and 13. Later in infancy or in adolescence, these rats were tested on a motor coordination task (Accelerod) while either sober or acutely intoxicated with ethanol (1 g/kg). During adolescence, animals had simultaneous access to varying ethanol concentrations (3, 4, 5, or 6% v/v) and water.

RESULTS

Both infants and adolescents that had been reared by ethanol-intoxicated dams exhibited dramatic behavioral impairments in the Accelerod task when compared with the offspring of water control dams. Ethanol intoxication disrupted motor performance in both age groups, but this effect was independent of prior maternal treatment. When tested for voluntary ethanol intake as adolescents, those with prior nursing experiences with an intoxicated dam ingested more ethanol than adolescents reared by sober dams.

CONCLUSIONS

Early experiences with alcohol comprising interactions with an alcohol-intoxicated dam result in motor impairment and enhanced ethanol intake later in life.

Chronic alcohol exposure and lactation: extended observations

Previous results from our laboratory have indicated that chronic (8 days) alcohol administration inhibits suckling-induced prolactin (PRL) release in response to 30 min of suckling. In addition, chronic alcohol administration to dams resulted in growth retardation of their litters. The present study was done to examine how an extended period of suckling (120 min) affected suckling-induced PRL release after chronic alcohol exposure. In addition, it was also examined whether the growth retardation observed during alcohol exposure persisted after alcohol infusions were discontinued. Dams were implanted with an atrial catheter on day 3 of lactation and saline or alcohol (1.0- or 2.0-g/kg BW) was administered daily for 8 days (lactation days 5 through 12). Following administration of the initial alcohol dose, the infusion was continued at rates required to maintain blood alcohol levels (BALs) for 4 h each day. Testing took place on day 12. As previously reported, suckling-induced PRL release was inhibited in dams receiving 2.0-g/kg alcohol after 30 min of suckling. However, after 120 min of suckling, PRL release in these dams was much higher than in either control or 1.0-g/kg alcohol dams. In addition, while the body weights of litters of dams administered 2.0-g/kg alcohol were reduced compared to litters of dams in the other two groups on days 8-16, their body weights rebounded and were not different from the other litters on days 18 or 20.

Infant rats respond differently to alcohol after nursing from an alcohol-intoxicated dam

Our previous studies indicate that rat pups are able to detect the low levels of ethanol (175 mg %) found in the milk of a moderately intoxicated dam. The present study tested the effect of infantile interactions (including suckling) with ethanol-treated mothers on later behavioral responsiveness to ethanol's sensory properties. In Experiment 1, pups suckled from dams subjected to a 2.5 g/kg ethanol dose (i.g.) or water-treated females during postnatal days (PDs) 3, 5, 7, 9, 11, and 13. During PD 15, these pups were exposed to procedures to induce a conditioned aversion to the low level of ethanol (175 mg % in water), with lithium chloride as the unconditioned stimulus. Conditioning was more effective for pups with the prior ethanol experience within the nursing context. Greater responsiveness to ethanol in milk also was found for conditioning control pups that had interacted with intoxicated dams than for those that had interacted with water-treated dams. Experiment 2 determined that interaction with an intoxicated dam was sufficient for altered responsiveness to ethanol, in that the additional conditioning procedures of Experiment 1 were not needed for the effect. Generally, a relatively brief history of infantile interaction with ethanol-intoxicated dams increased later responsiveness to ethanol's orosensory properties. The results suggest that moderately intoxicated dams within the nursing context provide information to the progeny that may lead to the establishment of ethanol-related memories.

Ethanol and lactation: effects of milk lipids and serum constituents

To determine how chronic alcohol administration during lactation affects milk composition and the nutritional status of the dam, EtOH (3 g/kg) as a 20% solution was administered by intubation to Sprague-Dawley rats from days 2 through 15 of lactation. Control dams were pair fed to account for the reduction in food intake observed in the alcohol group, while another control group maintained ad lib food intake. Dams and their litters were weighed daily throughout the study. On day 16, dams were sacrificed and samples taken for further analysis. Blood alcohol levels as well as serum levels of calcium, cholesterol, glucose, iron, lipids, phosphorous, and triglycerides were measured. Liver lipid levels and the total composition and fatty acid profile of the phospholipids in milk were also measured. Results indicate that EtOH administration and pair feeding reduced dam body weight, but not litter growth. Serum iron levels was increased in both EtOH-exposed and pair-fed controls, whereas serum cholesterol was elevated only in EtOH-exposed dams. Finally, of the phospholipids in milk, only one, phosphatidylserine, was slightly but significantly increased by EtOH. If and how these changes impact the development of the offspring remain to be studied.

Effects of chronic alcohol administration on lactational performance in the rat

Lactating rats, with litters adjusted to eight pups on day 2, were implanted with an atrial catheter on day 3 of lactation. Alcohol in doses of 0.0, 1.0, or 2.0 g/kg BW was infused from day 5 to 12. The blood alcohol levels (BALs) achieved following infusion of the initial doses were maintained for 4 hours daily by infusion. To control for the reduced food intake in alcohol administered groups, rats receiving alcohol doses of 0.0 and 1.0 g/kg BW were pairfed to 2.0 g/kg BW alcohol group. For infusion, combinations of 50% dextrose, 30% alcohol in saline and saline solutions were used for 0.0 and 1.0 g/kg BW alcohol groups whereas the 2.0 g/kg BW alcohol group received 30% alcohol in saline thereby equilizing the calorie intake of the three experimental groups. On day 12, pups were separated from the dams at 0800 h, a catheter extension was attached at 0900 h and baseline blood samples for prolactin level were taken at 1000 h. Following infusion of initial alcohol doses, samples were taken for BALs. Additional samples for BALs were removed 2 h after continuing the infusion. At the end of 4-h infusion, blood samples were taken for alcohol and postinfusion prolactin levels. In groups designed to study the suckling-induced prolactin release, pups were weighed and returned to the dams. Subsequent blood samples were taken 30 min after initiation of suckling. In nonsuckled groups, blood samples were obtained at corresponding time periods. BALs were determined by head space gas chromatography and plasma prolactin by a double antibody radioimmunoassay. Suckling latency and milk consumption during the 30 min of suckling were measured. Dams' and litter weights were determined on days 2, 5, and 12 of lactation. Infusion of alcohol for 8 days from day 5 to 12 of lactation did not affect maternal body weight. However, litters nursed by dams receiving 2.0 g/kg BW alcohol weighted less on day 12 compared to all other groups. Suckling latencies did not differ among groups. Milk consumed during the 30 min of suckling was lower for the alcohol administered groups. The inhibitory effect on milk consumption was greater for the 2.0 g/kg BW group than in the 1.0 g/kg BW alcohol group. Alcohol infusion did not affect the basal prolactin, whereas, the higher dose (2.0 g/kg BW) inhibited suckling-induced prolactin release.(ABSTRACT TRUNCATED AT 400 WORDS)

Lactational alcohol exposure elicits long-term immune deficits and increased noradrenergic synaptic transmission in lymphoid organs

Increasing evidence suggests that the sympathetic nervous system plays an important role in immunomodulation. While chronic alcohol consumption has been associated with immune deficits, the effects of exposure to alcohol during early postnatal life on subsequent immunocompetence and activity of sympathetic neurons in lymphoid organs are not known. This study examined the long-term effects of lactational alcohol consumption on cellular immune responses and noradrenergic synaptic transmission in lymphoid and other organs of the young adult C57BL/6 mouse. The data show that exposure to alcohol via the mother's milk was associated with long-term deficits in cellular immunity, including suppression of the local graft vs host and contact hypersensitivity responses. The animals also displayed enhanced noradrenergic synaptic transmission and decreased beta-adrenoceptor density selectively in lymphoid organs. These neuroimmune changes are particularly striking since body weight-gain of the suckling pups was normal and their blood alcohol concentration was considerably lower than that of the alcohol-consuming dam. This suggests an increased sensitivity of the nascent immune and nervous systems during the critical period of early postnatal development.