Arthur D. Hartman

Effects of different levels of caffeine supplemented to the maternal diet on the brains of newborn rats and their dams

At birth, dams with 8 randomly assigned pups were divided into three groups. Dams of group 1 were fed a control diet. Dams of groups 2 and 3 were fed the control diet supplemented with caffeine (1 mg and 2 mg/100 g body weight, respectively). Pups were killed at day 15 and their brains removed. After weighing, brains were analyzed for DNA, protein, cholesterol, zinc and alkaline phosphatase activity. Brain and plasma caffeine levels were also determined on groups 2 and 3. The dams were milked to measure caffeine levels. The brains from the dams were analyzed for the same parameters as the pups. Caffeine levels in group 3 were consistently higher than in group 2. In the pups, body and brain weights were heavier in group 3 than in the controls. Protein and cholesterol concentrations in group 2 were less than either controls or group 3. Alkaline phosphatase activity in group 2 was higher than either controls or group 3. In the dams, DNA concentration in groups 2 and 3 was less than the controls. Protein and cholesterol concentration in group 2 was less than group 3. It was concluded that low levels of caffeine in the maternal diet during lactation could affect various parameters in the newborn brain. These effects were different from those when the dietary caffeine level was doubled. In contrast, the effects of caffeine on brains of the dams were relatively minor.

Effect of Chronic Caffeine Intake on Myocardial Function during Early Growth

ABSTRACT: The purpose of these studies was to evaluate the effects of chronic caffeine ingestion on the myocardium during fetal and neonatal growth and development. The isolated perfused working heart preparation was used to evaluate cardiac function. During gestation and lactation, one group of dams consumed a caffeine supplemented diet (10 mg/kg/day). Their offspring were sacrificed and the hearts analyzed 50 days after birth. We found that the intake of caffeine by the dams resulted in significant increases in the offsprings coronary flow, peak systolic pressure, and myocardial work. A second group of dams ingested a diet containing caffeine (10 mg/kg/day) during lactation only. Their pups continued to consume the caffeine diet until 50 days. Pup hearts exhibited significant reductions in cardiac output, stroke volume, pressure development, myocardial work, and external efficiency when compared to controls. Caffeine did not affect (a) body or heart weight or (b) adipose size or number in these experiments. Thus, continued caffeine consumption following birth may alter cardiac performance of the offspring.

Adipocyte Fatty Acid Mobilization in vivo: Effects of Age and Anatomical Location

The objectives of the present study were to determine if adipocyte trigly ceride fatty acid (TGFA) mobilization in vivo varied among the different adipose tissue depots and whether these rates were affected by age. In order to accomplish these objectives, two groups of rats were studied. The first group initially weighed 84±1 and the second group 333±2. Both groups were placed on a semisynthetic diet containing 6% corn oil (w/w) and 14% triundecanoin (w/w) for a period of 4 wk. Triundecanoin contains an 11-carbon (C-11) fatty acid (undecanoic acid) that was used to label the adipocyte TGFA. At the end of the 4-wk feeding period, triundecanoin was removed from the diet and replaced with an equivalent amount of corn oil. At this time and at weekly intervals for the next 4 wk, 5 rats from each age group were killed for the determination of TGFA composition in isolated dipocytes from the epididymal (Epi), perirenal (PR), subcutaneous (SC) and mesenteric (M) adipose tissue depots. When the content of C-11 was expressed as mole percent of the total fatty acids, mobilization was significantly more rapid from the PR and M depots than in the other two depots in the young rats. In the older rats mobilization was significantly slower in all depots compared to the younger group. The rates of mobilization were not different between the depots in the older animals. Since fat cell size continued to increase throughout the duration of the study, part of the decrease in C-11 content can be accounted for by dilution by newly acquired TGFA. When data were compared on the basis of the actual pmoles of C-11 per cell, rates of mobilization were not different between the depots nor was mobilization affected by age. These results emphasize again the impact the manner in which adipocyte metabolic data are expressed has on interpretation(s) when comparing adipocytes of different depots or from rats of different age.

Chronic Caffeine Intake by Rat Dams during Gestation and Lactation Affects Various Parts of the Neonatal Brain

Timed-pregnant rats were randomly divided into 2 groups on day 13 of gestation. Group 1 received a 20% protein diet. Group 2 was pair-fed to group 1 with a 20% protein diet containing caffeine (1 mg/100 g body weight). At parturition, the dams of each group were continued on their respective diets until day 22 postpartum. At the time of weaning (day 22), only male rats were continued in the study. At this time, rats from both groups were fed the control diet containing 20% protein. On day 57 and 58, rats were killed, the brains divided into six areas, and DNA, RNA and protein contents were measured. In certain areas of the brain, weight, cholesterol, DNA, RNA and protein contents were different even long after returning to the caffeine-free control diet. The present study demonstrates that even if a relatively small amount of caffeine is taken during gestation and lactation, a time during which the growth rate is greater than in any other period of life, certain areas of the brain may be affected. These findings suggest that future central nervous system impairment may be expressed later in life in these offspring.

Chronic caffeine intake alters the composition of various parts of the brain in young growing rats.

Time-pregnant rats were fed a regular laboratory diet until delivery. Litters delivered within an 8-hour period were combined and 8 randomly selected pups were assigned to each dam. Dams were then divided into two groups. Group I received a 20% protein diet. Group II was pair-fed to group I with a 20% protein diet containing caffeine (1 mg/100 g body weight) until day 22 postpartum. On weaning (day 22), only male pups were selected and fed the 20% protein or 20% protein + caffeine diet according to which diet their respective dams had been fed. On day 43, rats were killed and the brains were divided into 6 different areas. DNA, RNA, protein and cholesterol contents were measured. Caffeine supplementation resulted in a decrease in the total brain weight, and DNA and RNA content. DNA value of cortex-midbrain was smaller in the caffeine group whereas the values of medulla oblongata and striatum were greater in comparison with the controls. Caffeines effects on RNA included an increase in the cerebellum, cortex-midbrain and hippocampus and a decrease in the medulla oblongata. Protein content of cerebellum was increased and of hippocampus decreased due to caffeine supplementation. Cholesterol content of the medulla oblongata and hippocampus was less in the caffeine group than in the control group. The present study shows that chronic caffeine intake during rapid periods of growth influences various parts of the brain in entirely different biochemical manners.

Effects of chronic caffeine ingestion on growth and myocardial function.

Abstract Experiments were conducted to determine whether chronic caffeine consumption during early growth and development affected cardiac performance and development of adipose tissue. Dams were fed a nutritionally complete diet with or without the addition of 10 mg/kg caffeine during lactation. After weaning, the pups were maintained on this diet until they were sacrificed at 88 days of age. Body weight at the time of sacrifice was comparable for both groups. The hearts from caffeine-fed animals were significantly (P <0.05) larger based on both dry and wet weights although the dry weight/wet weight ratios were similar. Ventricular function curves were generated on each heart using an isolated working heart preparation. The isolated hearts of caffeine-fed rats exhibited a significant reduction in cardiac output, stroke volume, mean aortic pressure, and estimated myocardial work when compared to controls. The rats fed caffeine had greater plasma triglyceride levels with no significant differences in adipocyte size or number in the epididymal and perirenal depots. It is concluded that chronic caffeine intake from birth may alter cardiac function of the offspring.

Interaction between Caffeine Intake and Nutritional Status on Growing Brains in Newborn Rats

The purpose of this study was to determine whether caffeines effects on the growing brain in suckling pups are modified by the nutritional status of the dams. Upon delivery, 8 randomly selected pups were assigned to each dam. They were divided into four groups; group 1 was fed a 20% protein diet as a control; group 2 was fed a 6% protein diet as a malnourished group; group 3 was pair-fed to group 1, but the 20% protein diet was supplemented with caffeine (2 mg/100 g body weight of dams), and group 4 was pair-fed to group 2 with a 6% protein diet with caffeine. At day 15, pups were killed. Brains were removed, weighted and homogenized. Caffeine content of plasma, brain of the pups and maternal milk in groups 3 and 4 were determined. Brains were analyzed for zinc, alkaline phosphatase activity, DNA, protein, and cholesterol. Body weight and protein content of group 3 were greater than group 1, but the zinc contents and alkaline phosphatase activity of group 3 were less than group 1. DNA and cholesterol contents of group 4 were greater than group 2. Supplementation of caffeine to the maternal diet appeared to have various effects on the growing brains of the suckling pups. Caffeines effects and nutritional status are closely interrelated.

Adipocyte Cholesterol Storage: Effect of Starvation

Abstract The content of free and esterified cholesterol in epididymal and subcutaneous adipocytes was measured during starvation in adult male rats in order to test the hypothesis that adipose tissue cholesterol esters are mobilized concomitantly with free cholesterol and triglyceride during starvation. Plasma and liver lipid concentrations were also determined as a function of time during food deprivation. Plasma triglyceride decreased significantly within 72 hr and liver triglyceride increased significantly after 144 hr of starvation. Plasma total cholesterol also decreased due to starvation, but only after 144 hr. No significant alteration in hepatic cholesterol was observed at any time. In epididymal adipose cells, free cholesterol was mobilized during fasting while the cholesterol ester pool remained constant. In marked contrast, cells from the subcutaneous depot showed no consistent changes in either free or esterified cholesterol despite the fact that cells lost about 55% of their triglyceride pool. These data provide another example of the metabolic heterogeneity of the various adipose tissue beds. Although neither cholesterol ester turnover nor hydrolase activity was directly measured, the results appear to be inconsistent with the hypothesis that an adipose tissue cholesterol ester hydrolase plays a role in the hydrolysis of stored esters during acute starvation, and further suggest that the turnover of cholesterol and cholesterol esters is probably different in adipose tissue.

Effects of Orally Administered Caffeine on Cellular Response in Protein Energy-malnourished Neonatal Rat Brain

ABSTRACT: The purpose of this study was to determine the effects of caffeine on growing rats and how protein energy malnutrition can modify these potential effects. Caffeine (1,3,7-trimethylxanthine) is not only the most commonly consumed, neurally active stimulant in our daily lives, but it is widely used in the management of apnea in the premature neonate. One group of dams (20%) (n = 6) was begun on a 20% protein diet ad libitum. The second group (6%) (n = 4) was begun on a 6% protein diet. A third group (20% + C) (n = 4) was pair-fed to group 1 (20%) with the 20% protein diet, but beginning on day 3 the pups received 10 mg/kg body weight of caffeine via intragastric feeding needle every other day. The fourth group (6% + C) (n = 5) was pair-fed with group 2 (6%) with the 6% protein diet and the pups received 10 mg/kg of caffeine in the same manner as the 20% + C group from day 3. Although the 6% protein diet was associated with the expected reduced body and brain growth, there were no additional growth alterations associated with caffeine administration in either the 20% or 6% diet groups. This growth failure was accompanied by the expected reductions in total whole brain DNA, RNA, protein, and cholesterol content regardless of whether caffeine was received or not. Effects of caffeine which were similar in both diet groups included an increase in brain RNA content and concentration and an increase in the RNA/DNA ratio. However, there were differential effects of caffeine seen depending on diet group assignment. These included an increase in brain DNA content and concentration in the 6% protein group only. Furthermore the protein/DNA ratio, an index of mean cell size, was increased in the 20% plus caffeine group and decreased in the 6% plus caffeine group. The present data and our previous work with theophylline on brain development (22) indicate that methylxanthine administration produces differential effects depending on dietary intake.

Adipose Tissue Cholesterol Storage: The Effect of Essential Fatty Acid Deficiency

Summary Essential fatty acid deficiency was induced in one group of rats by feeding a fat-free diet, and in another group by supplying hydrogenated coconut oil. All deficient animals had significantly reduced weight gain and tended to have decreased epididymal fat cell size compared to controls. Rats in the fat-free group had significantly more adipocyte free cholesterol than control animals, but no significant alteration in stored free sterol occurred in rats made essential fatty acid deficient with hydrogenated coconut oil. Between experimental essential fatty acid deficient groups, the fat-free group had greater quantities of adipocyte free, and hence, total cholesterol. No alterations in ester content due to essential fatty acid deficiency could be demonstrated, although the percentage of total cholesterol as esters decreased significantly in both experimental groups. It is suggested that adipose tissue responds differently than other peripheral tissues to essential fatty acid deficiency.