L-carnitine improves glucose disposal in type 2 diabetic patients

OBJECTIVE: Aim of the present study is to evaluate the effects of L-carnitine on insulin-mediated glucose uptake and oxidation in type II diabetic patients and compare the results with those in healthy controls. DESIGN: Fifteen type II diabetic patients and 20 healthy volunteers underwent a short-term (2 hours) euglycemic hyperinsulinemic clamp with simultaneous constant infusion of L-carnitine (0.28 micromole/kg bw/minute) or saline solution. Respiratory gas exchange was measured by an open-circuit ventilated hood system. Plasma glucose, insulin, non-esterified fatty acids (NEFA) and lactate levels were analyzed. Nitrogen urinary excretion was calculated to evaluate protein oxidation. RESULTS: Whole body glucose uptake was significantly (p<0.001) higher with L-carnitine than with saline solution in the two groups investigated (48.66+/-4.73 without carnitine and 52.75+/-5.19 micromoles/kg(ffm)/minute with carnitine in healthy controls, and 35.90+/-5.00 vs. 38.90+/-5.16 micromoles/kg(ffm)/minute in diabetic patients). Glucose oxidation significantly increased only in the diabetic group (17.61+/-3.33 vs. 16.45+/-2.95 micromoles/kg(ffm)/minute, p<0.001). On the contrary, glucose storage increased in both groups (controls: 26.36+/-3.25 vs. 22.79+/-3.46 micromoles/kg(ffm)/minute, p<0.001; diabetics: 21.28+/-3.18 vs. 19.66+/-3.04 micromoles/kg(ffm)/minute, p<0.001). In type II diabetic patients, plasma lactate significantly decreased during L-carnitine infusion compared to saline, going from the basal period to the end-clamp period (0.028+/-0.0191 without carnitine and 0.0759+/-0.0329 with carnitine, p<0.0003). CONCLUSIONS: L-carnitine constant infusion improves insulin sensitivity in insulin resistant diabetic patients; a significant effect on whole body insulin-mediated glucose uptake is also observed in normal subjects. In diabetics, glucose, taken up by the tissues, appears to be promptly utilized as fuel since glucose oxidation is increased during L-carnitine administration. The significantly reduced plasma levels of lactate suggest that this effect might be exerted through the activation of pyruvate dehydrogenase, whose activity is depressed in the insulin resistant status.     

Determination of RBC membrane and serum lipid composition in trinidadian type II diabetics with and without nephropathy

Aim:

The rheological properties of erythrocytes are impaired in diabetes mellitus, especially because of changes in their membrane lipid composition.The aim of this study was to determine and examine the relationship between red blood cell (RBC) membrane and serum lipid composition in type II diabetes subjects with and without nephropathy.

Methods:

Trinidadian subjects aged 18–65 years were recruited for the study regardless of gender and ethnicity. Fasting blood samples were collected from 60 subjects of whom 20 were healthy individuals, 20 had type II diabetes without complications, and 20 were type II diabetics with nephropathy. Weight, height, waist/hip ratio, and blood pressure were recorded. All the blood samples were analysed to determine the serum lipid concentration, membrane lipid composition and plasma glucose concentration.

Results:

The body mass index and the systolic blood pressure of the diabetics (28.17 ± 4.98 kg/m², 153.21 ± 22.10 mmHg) and those with nephropathy (25.87 ± 4.68, 158.60 ± 22.49 mmHg) were higher when compared with controls (24.67 ± 5.18, 119.15 ± 13.03 mmHg). The diabetic (175.89 ± 102.73 μg/mgprotein) and diabetic nephropathy (358.80 ± 262.66) subjects showed significantly higher levels of RBC membrane cholesterol compared with controls (132.27 ± 66.47). The membrane phospholipids, protein and Na⁺/K⁺ATPase concentrations were altered in diabetics and diabetic nephropathy patients when compared with controls. The trends of increased serum cholesterol and decreased high-density lipoprotein in diabetics and diabetic nephropathy patients were noted as compared with controls but they are not significant as expected. The low-density lipoprotein cholesterol was significantly higher in diabetics when compared with diabetic nephropathy and control subjects.

Conclusions:

Our data suggest that there is a relationship between RBC membrane and serum lipid composition in subjects with type II diabetes with and without nephropathy. This relationship shows that diet and lifestyle plays a significant role in the alterations of the lipids both in serum and RBC membrane. The membrane and serum lipid composition may be used as possible indicators for type II diabetic patients with and without nephropathy to control their diet in the beginning stages to prevent them from further complications.     

Changes in glycosylated proteins in diabetic and non-diabetic patients with and without cardiovascular complications

The objective of this study was to find the changes in glycoprotein composition in both diabetic and non-diabetic patients with and without cardiovascular complications. The study was carried out in Ziauddin Medical University Karachi, Pakistan. Eighty-three patients and control subjects were selected. Among them twenty-one were diabetic patients without any clinical evidence of chronic diabetic complications, twenty-one were diabetic patients with cardiovascular complications, twenty were non-diabetic patients with cardiovascular complications and twenty-one apparently normal, age, sex and weight matched control subjects were investigated. All these patients were selected on clinical grounds from National Institute of Cardiovascular Disease, Karachi. Fasting plasma glucose was increased in all diabetic patients and correlated significantly with and without cardiovascular complications. Fasting plasma glucose, glycosylated haemoglobin, glycosylated plasma proteins, serum fructosamine, sialic acid, hexosamine and total serum protein and its fractions were increased in diabetic patients with and without cardiovascular complications. Fasting plasma glucose, glycosylated haemoglobin, glycosylated plasma proteins, serum fructosamine, sialic acid and hexosamine were not different in diabetic patients with cardiovascular complications and diabetic patients without chronic complications as compared with control subjects. In conclusion, fasting plasma glucose, glycosylated haemoglobin, glycosylated plasma proteins, serum fructosamine, sialic acid, hexosamine and total serum proteins and its fractions were increased in diabetic patients with and without complications, but these parameters remained within normal limits in non-diabetic patients with cardiovascular complications.     

Effect of L-carnitine on plasma glycemic and lipidemic profile in patients with type II diabetes mellitus

OBJECTIVE: We designed this study to investigate the effects of oral L-carnitine administration on fasting plasma glucose (FPG), glycosylated hemoglobin (HbA1c) and lipid parameters in patients with diabetes mellitus type II. PATIENTS AND METHODS: The effect of L-carnitine on FPG and lipid parameters was investigated in 22 male and 13 female type II diabetic patients; the mean age +/- s.d. was 51.3 +/- 3.7 y. The patients were randomly allocated to two groups (L-carnitine and placebo group) and 1 g of L-carnitine or of placebo was given orally three times a day for a period of 12 weeks. RESULTS: FPG in the L-carnitine group decreased significantly from 143 +/- 35 to 130 +/- 33 mg/dl (P = 0.03), and we observed a significant increase of triglycerides (TG) from 196+/-61 to 233+/-12 mg/dl (P = 0.05), of Apo A1 from 94 +/- 20 to 103 +/- 23 mg/dl (P = 0.02), and of Apo B100 from 98 +/- 18 to 108 +/- 22 mg/dl (P = 0.02) after 12 weeks of treatment. There was no significant change in LDL-C, HDL-C, HbA1C, LP(a) or total cholesterol. CONCLUSION: L-Carnitine significantly lowers FPG but increases fasting triglyceride in type II diabetic patients.     

Diets and hormonal levels in postmenopausal women with or without breast cancer

The role of diet in breast cancer (BC) risk is unclear. Fiber could reduce BC risk, through the enterohepatic circulation of estrogens. We examined the relationship between diet and sex hormones in postmenopausal women with or without BC. Thirty-one postmenopausal women (10 omnivores, 11 vegetarians, and 10 BC omnivores) were recruited. Dietary records (5 days) and hormone levels (3 days) were evaluated on 4 occasions over 1 yr. Vegetarians showed a lower fat/fiber ratio, a higher intake of total and cereal fiber (g/d)/body weight (kg), a significantly lower level of plasma estrone-sulfate, estradiol, free-estradiol, free-testosterone, and ring D oxygenated estrogens, and a significantly higher level of sex-hormone-binding-globulin than BC subjects. Fiber was consumed in slightly larger amounts by omnivores than by BC subjects. Omnivores had significantly lower plasma testosterone and estrone-sulfate but higher sex-hormone-binding-globulin than BC subjects. No difference was found for the urinary 16-oxygenated estrogens. However, the 2-MeO-E1/2-OH-E1 ratio was significantly lower in omnivores than in BC group. This ratio is positively associated with the fat/fiber ratio. In conclusion, testosterone may contribute to causing alterations in the levels of catechol estrogens and 16-oxygenated estrogens. The fat/fiber ratio appears to be useful in evaluating dietary effects on estrogen metabolism.     

2型糖尿病血管病变患者血小板相关参数的变化

目的 探讨血小板相关参数在2型糖尿病患者中的改变及临床意义.方法 选取128例2型糖尿病住院患者,根据患者是否出现血管病变分为血管病变组（49例）和无血管病变组（79例）,分别检测各组的血小板计数（PLT）、平均血小板体积（MPV）、平均血小板分布宽度（PDW）和大血小板（L-PLT）,并与50例健康体检者（对照组）进行比较分析.结果 血管病变组患者MPV、PDW和L-PLT较无血管病变组增高[（13.98±2.35） fl比（11.53±2.06）n、（15.87±2.18）n比（13.51±2.01） fl、（10.91±1.34）×109/L比（8.72±1.03）×109/L],PLT较无血管病变组降低[（115.2±10.5）×109/L比（129.6±8.7）×109/L],差异均有统计学意义（P＜0.05）.血管病变组MPV、PDW、L-PLT、PLT与对照组[（10.41±1.95）n、（11.15±1.88）n、（6.21±0.98）×109/L、（176.5±7.2）×109/L]比较差异有统计学意义（P＜0.05）.结论 血小板相关参数检测有助于糖尿病血管病变的临床诊断,对疾病的临床诊疗和病情监测有重要意义.     

Association of gender with symptoms and complications in type II diabetes mellitus.

Females with Type II diabetes appear more likely than males to experience symptoms and vascular complications related to their disease.     

Determination of alpha-tocopherol in plasma, platelets and erythrocytes of type I and type II diabetic patients by high-performance liquid chromatography

Vitamin E (alpha-tocopherol) concentrations of plasma, platelets and erythrocytes were determined by HPLC in insulin-dependent (type I) and age-matched non-insulin-dependent (type II) diabetic patients and in two control groups. Plasma alpha-tocopherol levels were significantly increased in diabetic patients compared to control groups. Platelet and erythrocyte alpha-tocopherol levels were not significantly different in type I and type II diabetics as compared to their respective control groups, but differed from one another. Plasma vitamin E concentrations showed a significant correlation with plasma cholesterol and apoprotein B concentrations in different groups. The alpha-tocopherol/cholesterol and alpha-tocopherol/apoprotein B ratios in plasma were higher in diabetic patients, as were triglyceride contents. Platelet vitamin E levels were not significantly correlated with plasma concentrations. These findings suggest that vitamin E activity is altered in diabetic patients but that no diet supplementation seems necessary.     

Decreased free testosterone and dehydroepiandrosterone-sulfate (DHEA-S) levels in women with decreased libido

A prior study has shown that premenopausal women could have decreased testosterone levels and still have regular menstrual cycles (Guay, 2001). Since ovarian function in such women was normal, the question of a possible adrenal dysfunction causing androgen deficiency was considered. If this was true, the question then arose as to whether the same defect could be seen in postmenopausal women. We studied 105 women who presented during a 6-month period of time with the chief complaint of decreased sexual desire. On subsequent testing, 74 of the women (70%) were found to have decreased total testosterone, free testosterone, and dehydroepiandrosterone sulfate (DHEA-S). Thirty-six of these women were premenopausal (ages range 24-50 years), and 38 were postmenopausal (ages range 47-78 years). All androgen levels for the women were lower than age-matched control groups found in the literature. The decreased DHEA-S levels suggest a a defect in adrenal steroidogenesis, which was seen in both premenopausal and postmenopausal women. Possible defects in regulatory mechanisms of adrenal steroidogenesis are discussed.     

2型糖尿病大血管病变风险及其交互作用分析

目的 探讨2型糖尿病病人(type 2 diabetes mellitus,T2DM)合并大血管病变的危险因素以及危险因素之间的交互作用.方法 设计调查问卷,收集1999年1月～2010年12月期间在广州市某医院住院的2型糖尿病患者的病历资料,包括年龄、性别、病程等19个变量.采用分类树对危险因素进行定性的交互作用分析,采用非条件Logistic回归模型定量分析危险因素的交互作用效应.结果 单纯T2DM无并发症的患者595例,T2DM合并大血管病变754例.建立分类树模型,包括3层,7个结点,4个终末节点,筛选出年龄、总胆固醇(total cholesterol,TC)、病程、高密度脂蛋白(high-density lipoprotein,HDL)、TC/HDL、三酰甘油(triacylglycerol,TG)、低密度脂蛋白(low density lipoprotein,LDL)、体重指数(body mass index,BMI)共8个危险因素.而与2型糖尿病大血管病变关联最密切的是年龄、病程和BMI.非条件Logistic回归分析结果显示:年龄与病程(OR=6.215,95％ CI:2.867～13.476,P＜0.001)、年龄与BMI(OR =2.484,95％ CI:1.465～4.212,P=0.001)在2型糖尿病进展大血管病变中存在交互作用.结论 年龄、病程和BMI相互作用是T2DM合并大血管病变的重要危险因素,年龄超过56岁,病程超过10年的患者应重点监测和干预,以防止大血管病变的发生.     

血清C-肽水平与2型糖尿病患者血管病变的关系

目的 研究2型糖尿病患者血清C-肽与血管病变的关系。方法 选择2015年3月－2017年12月三门峡市中心医院收治的2型糖尿病患者97例,按照患者是否合并血管病变将其分为血管病变组38例,非血管病变组59例。对比两组患者年龄、性别、病程、体质量指数等基本资料,血脂、血糖、空腹C-肽以及餐后1 h C-肽水平,并应用多因素Logistic回归分析分析血管病变的危险因素。结果 血管病变组患者年龄(61.37±9.38)岁、病程(8.17±3.45)年均明显高于非血管病变组的,差异均有统计学意义(t=4.335、3.567,P＜0.05)。血管病变组患者三酰甘油(1.70±0.82)mmol/L、低密度脂蛋白胆固醇(3.13±1.05)mmol/L、餐后1 h血糖(18.44±4.21)mmol/L以及糖化血红蛋白(9.65%±1.83%)水平明显高于非血管病变组,差异均有统计学意义(t=2.372、2.074、3.072、2.276,P＜0.05)。血管病变组患者血清空腹C-肽(0.73±0.62)μg/L以及餐后1 h C-肽(1.62±0.83)μg/L水平明显低于非血管病变组(t=3.281、3.616,P＜0.05)。多因素Logistic回归分析显示、三酰甘油(OR=2.536)、低密度脂蛋白胆固醇(OR=2.187)、餐后1 h血糖(OR=2.561)以及糖化血红蛋白(OR=2.105)是2型糖尿病患者血管病变危险因素,而血清空腹C-肽(OR=0.482)、餐后1 h C-肽(OR=0.435)是2型糖尿病患者血管病变的保护因素。结论 2型糖尿病患者血清C-肽水平的降低可能是导致血管病变发生、发展的重要因素之一,C肽可能对2型糖尿病患者血管病变起一定的保护作用。     

社区主导的同伴教育对女性2型糖尿病患者影响的研究

目的 探讨社区主导的同伴教育对女性2型糖尿病患者的影响.方法 将80例女性2型糖尿病患者随机分为对照组和观察组,各40例,对照组进行常规健康教育,观察组在常规健康教育基础上,进行同伴教育干预.观察干预前、后两组患者对糖尿病知识掌握、心理变化相关行为形成及血糖变化.心理变化用焦虑自评量表(SAS)和抑郁自评量表(SDS)进行测评.结果 干预前两组患者的相关知识掌握、SAS及SDS得分、相关行为形成率及血糖变化差异无统计学意义(χ2=0.06～40.83,t=0.92～4.97,均P＞0.05).干预后观察组对糖尿病知识掌握≥90分的百分率较对照组高,差异有统计学意义(χ2=8.90,P＜0.01);干预后观察组SAS、SDS得分较对照组低,差异有统计学意义(t=3.85、3.81,P＜0.01);两组患者遵医行为等相关行为形成率有所提高,(χ2=5.33～48.32,均P＜0.05),表现在饮食、运动、保健、监测、治疗依从性等5个方面;两组患者空腹血糖(FBG)、餐后2小时血糖(PBG)、糖化血红蛋白(HbAIc)水平有所降低,差异均有统计学意义(t=-5.01～8.46,P＜0.05).结论 主导的同伴教育可促使女性2型糖尿病患者更好地接受糖尿病健康知识,显著减少负性情绪,同时提高患者相关行为的形成率,改善血糖水平.     

Health-related quality of life in type 1 diabetes without or with symptoms of long-term complications

Objective: To measure subjective health-related quality of life (HRQoL) of patients with type 1 diabetes and describe the influence of symptoms of diabetes-related long-term complications on HRQoL. Methods: The 15-D health-related quality of life measure (15D) was used to measure HRQoL of a representative sample of Finnish insulin-treated patients expected to have type 1 diabetes. Background data were gathered with a separate questionnaire. A tobit (censored regression) model was constructed to estimate the effects of symptoms of complications on HRQoL and to separate these effects from those of other health problems and aging. Results: The 15D scores declined markedly with increasing age, and the prevalence of symptoms of long-term complications increased. The tobit regression model showed that these symptoms have a significant negative influence on HRQoL. The model explained over 50% of the variation in the 15D scores. Conclusions: High prevalence of symptoms of long-term complications combined with their significant negative influence on HRQoL causes substantial losses in terms of quality of life and utility from both individual and societal perspectives. Thus, the importance of secondary prevention, i.e., prevention of complications by better metabolic control, and also the so-far theoretic possibility to prevent type 1 diabetes itself is emphasized.     

Body composition and pulmonary function in obese type 2 diabetic women

Most patients with Type 2 diabetes mellitus (T2DM) are overweight and their fat-distribution pattern shows more truncal and less peripheral subcutaneous fat. Obesity also influences the respiratory system by mechanical effects on the diaphragm and chest wall depending on the distribution and size of excess adipose tissues. To determine if the impairment of pulmonary function in T2DM is associated with truncal fat distribution, we performed dynamic spirometric tests and body composition analysis, by dual X-ray absorptiometry, in 12 non-smoker mildly obese T2DM women and in an equal number of control normoglycaemic females, matched for age, body mass index and smoking habits. The forced vital capacity and forced expiratory volume in one second for T2DM women (2.67 +/- 0.30 and 2.15 +/- 0.20 1, respectively) were significantly (p < 0.05) lower than for control women (3.22 +/- 0.30 and 2.58 +/- 0.31 1, respectively). However, trunk fat mass and trunk lean body mass for T2DM women (16.68 +/- 2.31 and 20.87 +/- 1.91 kg, respectively) were comparable with those for controls (16.46 +/- 2.54 and 19.65 +/- 3.42 kg, respectively). Thus, we deduce that pulmonary function impairment in T2DM obese women is not associated with truncal fat mass deposition or with lean mass depletion.     

Correlation of microalbumin and sialic acid with anthropometric variables in type 2 diabetic patients with and without nephropathy

Aim

The objective of this study is to correlate microalbumin and sialic acid levels with anthropometric variables in type 2 diabetic patients with and without nephropathy.

Methods

This study was a case control study and included 108 Trinidadian subjects (aged 15–60 years) of which 30 were healthy individuals, 38 had type 2 diabetes, and 40 were of type 2 diabetic patients with nephropathy. Blood pressure and waist to hip ratio were recorded. Fasting venous blood samples and urine samples were collected from all the subjects. Blood samples were analysed for the glucose, C-reactive protein, and sialic acid. Urine sample was analysed for microalbumin and sialic acid.

Results

Urinary microalbumin was higher among diabetic subjects (28.9 ± 30.3 mg/L) compared with controls (8.4 ± 10.2 mg/L) and was significantly higher in diabetic patients with nephropathy (792.3 ± 803.9 mg/L). Serum sialic acid was higher in subjects with diabetic nephropathy (71.5 ± 23.3 mg/dL) compared to diabetics (66.0 ± 11.7 mg/dL) and controls (55.2 ± 8.3 mg/dL). Increased microalbumin and sialic acid were correlated with other cardiovascular risk factors such as hypertension and waist to hip ratios (p < 0.05).

Conclusions

From these results it can be concluded that the increased microalbumin and sialic acid were strongly correlated with hypertension and waist to hip ratios in Trinidadian type-2 diabetic patients. Measurement of sialic acid, microalbumin, and waist to hip ratio along with the blood pressure is recommended for all type 2 diabetic patients to reduce the cardiovascular risk.     

2型糖尿病患者角膜神经形态与糖尿病微血管并发症关系研究

目的评价糖尿病患者角膜神经形态变化与糖尿病视网膜病变及糖尿病肾病的关系。方法纳入95例2型糖尿病患者及30例健康志愿者(对照组)进行角膜共聚焦显微镜检查,以评价角膜神经形态改变。糖尿病患者进行微血管并发症检查,分为糖尿病周围神经病变组(DPN)及无糖尿病周围神经病变组(NDPN);糖尿病视网膜病变组(DR)及无糖尿病视网膜病变组(NDR);糖尿病肾病组(DN)及无糖尿病肾病组(NDN)。结果角膜神经纤维密度(CNFD)、角膜神经分支密度(CNBD)、角膜神经纤维长度(CNFL)等在NDPN组、NDR组、NDN组较健康对照组显著降低(P0.001),DPN组、DR组、DN组较NDPN组、NDR组、NDN组进一步降低(P0.001)。CNFD、CNBD、CNFL与腓总神经运动神经传导速度(PMNCV)、腓肠神经感觉神经传导速度(SSNCV)及腓肠神经波幅(SSmv)显著相关(P0.01)。结论角膜神经改变可早期诊断糖尿病周围神经病变,在未发生糖尿病视网膜病变或糖尿病肾病的患者中即可检出角膜神经病变。     

Fibronectin and lipoprotein(a) are inversely related to plasminogen activator inhibitor type-1 levels in Type 2 diabetic patients without complications

Plasminogen activator inhibitor type-1 (PAI-1), the most important physiological fibrinolysis inhibitor, is considered an independent factor of cardiovascular risk in Type 2 diabetes mellitus (T2DM). In previous papers we demonstrated that a T2DM population without complications presents: 1) PAI-1 not increased with respect to a control group; and 2) a negative correlation between PAI-1 and lipoprotein(a) [Lp(a)], suggesting that in these subjects PAI-1 levels could be modulated by the "endothelial stress" induced by Lp(a) and diabetes. This work has been performed in order to better verify this intriguing hypothesis, and the endothelial stress has been evaluated through a marker of endothelial damage, fibronectin (FNC). For this purpose we chose a T2DM population without complications (n=73) and a control group (n=46). Plasma concentrations of FNC, Lp(a), PAI-1 antigen and activity, and the main parameters of lipo- and glycometabolic balance were determined. Fibronectin was significantly higher in diabetics with respect to controls (p<0.01). As expected, significant correlation between PAI-1 antigen, PAI-1 activity and Lp(a) (r=-0.54,p<0.01 and r=-0.39,p<0.01, respectively) was found only in diabetic patients. In the same group FNC showed a significant correlation with PAI-1 antigen and activity (r=-0.49,p<0.01 and r=-0.47; p<0.01, respectively), while no relationship was found between Lp(a) and FNC. Multiple regression analysis showed statistically significant correlation between PAI-1 antigen and PAI-1 activity with FNC and Lp(a) in diabetic patients without complications (p<0.05). These data suggest that in absence of complications, the endothelium is able to modulate PAI-1 levels, favouring in that way the fibrinolytic pathway and, subsequently, the recovery of the endothelial integrity. This modulation seems to be related to parameters such as Lp(a) and FNC, although the mechanisms of the endothelial stress of these two molecules seem to be different.     

Tissue carnitine concentrations after total parenteral nutrition with and without L-carnitine supplementation

The concentrations (mumoles/g dry weight) of total carnitine (TC), free carnitine (FC) and acylcarnitine (AC) were determined in skeletal muscle, heart, liver, kidney and brain cortex of male mini pigs (4000-5000 g) after seven days of total parenteral nutrition (TPN) with amino acids 5% (3.0g/kg/d), glucose (25g/kg/d) and lipids 20% (4g/kg/d). This regime was administered with L-carnitine supplementation (1.5 mg/kg/d; n = 7) (group 1) and without it (n = 5) (group 2). Orally alimented animals (n = 5) served as controls (group 3). (Average carnitine intake: 3 mg/d) Carnitine free TPN affected only the concentrations in muscle. TC was markedly reduced (3.6 +/- 0.8) when compared with oral controls (5.8 +/- 0.7) (p<0.01). This decrease was exclusively due to AC, whereas FC concentrations remained almost unchanged. In group 1 the concentrations of TC in skeletal muscle, heart and brain cortex were higher than in both the other groups. The increase was mainly due to AC and FC remained unchanged in heart and brain. The concentrations in liver and kidney were not affected by either carnitine free or carnitine supplemented TPN. AC, determined as described, consists almost entirely of acid soluble acetyl-carnitine, the major product of fatty acid oxidation. Since the AC concentrations were almost exclusively altered by the two TPN-regimes we conclude that the observed changes reflect regulatory changes of fatty acid oxidation. Thus the decrease of muscle TC in group 2 is considered a consequence of an insulin induced down regulation (plasma insulin: mean 20 muU/ml; maximum: 60 muU/ml) of fatty acid oxidation in consequence of high glucose intake (25 g/kg/d). The increased TC concentrations after carnitine supplemented TPN are discussed to reflect an enhancement of oxidative degradation of fatty acids as a pharmacological effect of L-carnitine.