Search PubMed⌕ Search

Biomedical subjects

F A Gries

Publications and source records attributed to F A Gries.

At least 181 records · Page 10Linked to original sources

Glucose metabolism in perfused skeletal muscle. Demonstration of insulin resistance in the obese Zucker rat.

1. The effect of insulin (0.5, 10 and 50 munits/ml of perfusate) on glucose uptake and disposal in skeletal muscle was studied in the isolated perfused hindquarter of obese (fa/fa) and lean (Fa/Fa) Zucker rats and Osborne-Mendel rats. 2. A concentration of 0.5 munit of insulin/ml induced a significant increase in glucose uptake (approx. 2.5 mumol/min per 30 g of muscle) in lean Zucker rats and in Osborne-Mendel rats, and 10 munits of insulin/ml caused a further increase to approx. 6 mumol/min per 30 g of muscle; but 50 munits of insulin/ml had no additional stimulatory effect. In contrast, in obese Zucker rats only 10 and 50 munits of insulin/ml had a stimulatory effect on glucose uptake, the magnitude of which was decreased by 50-70% when compared with either lean control group. Since under no experimental condition tested was an accumulation of free glucose in muscle-cell water observed, the data suggest an impairment of insulin-stimulated glucose transport across the muscle-cell membrane in obese Zucker rats. 3. The intracellular disposal of glucose in skeletal muscle of obese Zucker rats was also insulin-insensitive: even at insulin concentrations that clearly stimulated glucose uptake, no effect of insulin on lactate oxidation (nor an inhibitory effect on alanine release) was observed; [14C]glucose incorporation into skeletal-muscle lipids was stimulated by 50 munits of insulin/ml, but the rate was still only 10% of that observed in lean Zucker rats. 4. The data indicate that the skeletal muscle of obese Zucker rats is insulin-resistant with respect to both glucose-transport mechanisms and intracellular pathways of glucose metabolism, such as lactate oxidation. The excessive degree of insulin-insensitivity in skeletal muscle of obese Zucker rats may represent a causal factor in the development of the glucose intolerance in this species.

Adipose Tissue↗

Increased growth of human fibroblasts and arterial smooth muscle cells from diabetic patients related to diabetic serum factors and cell origin.

Fibroblasts from 3 diabetic patients (DF) grew faster, resulting in higher cell counts in the stationary phase than fibroblasts from 3 age-matched healthy volunteers (NF). This difference was apparent when DF or NF were cultured in either diabetic (DS) or normal serum (NS). Diabetic serum increased growth of both DF and NF compared with normal serum. Total protein content per plate paralleled the increase of cell number per plate in relation to cell origin and serum type. DS increased growth and total protein per plate in the arterial smooth muscle cell line from a non-diabetic patient in a way similar to in DF and NF. It is concluded that increased growth of DF in vivo could result in an increased turnover of vascular cells with a shortened replicative lifespan, leading to an accumulation of basal lamina. This effect would be even further accentuated by exposure of DF to DS. Taken together with the increased protein synthesis the accelerated development of diabetic angiopathy could be the final consequence.

Adolescent↗

[Obesity and cardiovascular risk].

Epidemiological studies on the relationship of obesity, morbidity and mortality revealed the following results: In life insurance studies, excess mortality of obese people was found with more than 30 percent overweight. Mortality was caused by cardiovascular disease and diabetes mellitus. Obesity at issue of the policy in younger age was a greater risk than in the older age group. In prospective studies with long follow-up periods (greater than 16 years) it could be shown that obesity alone was a risk factor for coronary heart disease, the risk being greatest for men and middle aged women. However, the prevalence of accepted risk factors in an obese population is so high that the question whether obesity alone is a risk factor for coronary heart disease is of little interest. The correlations between obesity and risk factors were of minor magnitude; therefore other factors, such as age or HDL-cholesterol, should be considered in the elucidation of the relationship between obesity and coronary heart disease. HDL-cholesterol appears to be a powerful independent protective factor which is diminished in obesity. Despite the fact that studies proving a prolongation of life by treating obesity are not available, the treatment of obesity may be beneficial for the patient by diminishing risk factors.

Adult↗

Blood amine acid levels in patients with insulin excess (functioning insulinoma) and insulin deficiency (diabetic ketosis).

Blood amino acid concentrations were determined in the postabsorptive state in nine patients with insulin excess (functioning insulinomas), nine juvenile-type diabetics with insulin deficiency (diabetic ketosis due to insulin withdrawal), six juvenile diabetics in moderate metabolic control, and five healthy control subjects. Blood branched-chain amino acid (BCAA) levels were elevated in diabetic ketosis and decreased in patients with insulinomas. Blood concentrations of BCAA were significantly correlated to blood glucose levels, and in diabetics they were also correlated to blood ketone bodies, serum free fatty acids, and glycerol levels. These data indicate an inverse relationship between circulating effective insulin levels and blood BCAA concentrations. It is suggested that blood levels of BCAA might represent an indicator of insulin-dependent alterations of protein metabolism.

Adenoma, Islet Cell↗

[Treatment of primary hyperlipoproteinemia type IIb and IV. Comparison of the lipid lowering effect of phenformin, clofibrate, and a combination of both (author's transl)].

22 outpatients with primary hyperlipoproteinemia type IIb and IV were treated in periods of eight weeks as follows: placebo; 0,15 g phenformin/day; 0,15 g phenformin + 1,5 g clofibrate/day; 1,5 g clofibrate/day; placebo. Compared to the first placeboperiode the serumtriglycerides were significantly lowered by phenformin (about 26%), by the combined treatment with phenformin + clofibrate (60%) and by clofibrate (51%) after eight weeks of treatment. The serumcholesterol was significantly lowered by phenformin (10%) and by the combined treatment with phenformin and clofibrate (14%), but not significantly by clofibrate (8%). After eight weeks of treatment with phenformin alone or in combination with clofibrate the body weight decreased significantly (1,9% or 1,4%). These changes in body weight were not related to changes in blood lipids. In conclusion, the combined treatment with 0,15 g clofibrate/day was more effective in lowering increased serum lipids than the treatment with phenformin or clofibrate alone.

Adult↗

[Treatment of primary hyperlipoproteinemias of type IIB and IV with butylbiguanide and clofibrate (author's transl)].

21 patients with primary hyperlipoproteinemias of type IIb and IV were treated for 8 weeks with placebo, 8 weeks with 0.3 g butylbiguanide and 1.5 g clofibrate/day and then for 8 weeks with 1.5 g clofibrate/day. In 12 patients a second placebo phase of 8 weeks followed. After 8 weeks of combined treatment with butylbiguanide and clofibrate the serum triglycerides decreased from 725 mg to 269 mg/100 ml. During the following period of clofibrate treatment the serum triglycerides increased after 4 and 8 weeks to 326 mg and 306 mg/100 ml respectively. The combined treatment with 0.3 g butylbiguanide and 1.5 g clofibrate/day is more effective in lowering elevated serum triglycerides and cholesterol than 1.5 g clofibrate alone.

Adult↗

Effects of metformin on glucose metabolism of isolated perfused rat skeletal muscle.

It was investigated whether N,N-dimethylbiguanide hydrochloride (metformin) lowers blood glucose levels by stimulating glucose uptake of skeletal muscle using the isolated perfused rat hindquarter. Osborne-Mendel rats were subjected to a special feeding regimen (food intake only 2 h daily) and were treated orally by metformin (125 mg/kg body weight twice daily) or placebo, respectively. The hypoglycemic effect of metformin could be demonstrated. Thereafter, control rats were perfused in the absence, and metformin-treated rats in the presence of added metformin (0.67 microgram/ml perfusate). Neither the basal nor the insulin-stimulated glucose uptake of skeletal muscle was increased by metformin. Lactate and alanine release, O2 uptake as well as the tissue metabolite levels of glucose, lactate, pyruvate, ATP and creatine-P remained unaffected. On the other hand, metformin caused a significant decline of lactate oxidation as well as an elevated glycogen content of skeletal muscle. It is proposed that the inhibition of lactate oxidation may under certain conditions be instrumental in the development of lactic acidosis associated with biguanide therapy.

Adenosine Triphosphate↗

Cardiovascular risk factors in gross obesity.

In 500 obese patients (146 men, mean age 37 +/- 13 years, Broca index 147 +/- 24; 354 women, mean age 36 +/- 14 years, Broca index 151 +/- 28) cardiovascular risk factors (RF) were investigated. The most frequent RF was hypertension (71 per cent), followed by glucose intolerance (49 per cent), hypertriglyceridemia (31 per cent), hypercholesterolemia (22 per cent) and hyperuricemia (22 per cent). Only 12 per cent of the patients were without RF. These patients were younger and less obese than the patients with RF. The prevalence of RF increased with increasing age and overweight. Analysis revealed significant correlations between overweight and blood pressure, blood glucose, insulin and age. Significant correlations between age and hypertension, blood glucose cholesterol, triglycerides and overweight were detected. The correlation between overweight and the sum of all RF was higher (r = 0.35) than the one between age and the sum of all (r = 0.23). Obese patients had a high prevalence of RF. Increasing overweight and (to a lesser extent) age are both associated with increased prevalence of RF. On the basis of the prevalence of RF, patients with gross obesity (Broca index greater than around 150) were considered to be at a high risk in respect of coronary heart disease.

Adult↗

[The treatment of chronic insulin resistance in adipose diabetics--interruption for a short time of diet and insulin administration (author's transl)].

Treatment of chronic insulin resistance in 3 adipose diabetics is reported. The clinical course shows that the actual success of the treatment of resistance depends less on weight reduction than on a short interruption of the insulin therapy and withdrawal of nutriment at the same time. After breaking off nourishment and insulin supply, the efficacy of the insulin therapy could be regained, at least partially, in all patients, and the diabetic metabolic state improved. In addition to the reduction in hyperinsulinism, physical activity and specific effects of diet are also probably important for the success of the treatment.

Aged↗