Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adrenergic control over intestinal homeostasis has been associated with changes in intestinal vascular resistance, motility, and transport. With the use of selective alpha-adrenergic agents, this study was designed to discriminate between the vascular and transport effects. Rabbit 20 cm ileal segments (n = 31) were vascularly perfused at a rate of 1.5 ml/min by means of a modified Krebs solution containing 15% to 20% red cells. The intestinal lumen was perfused with an isotonic solution containing carbon 14-polyethylene glycol as a nonabsorbable marker. Net fluxes of water and electrolytes were calculated during 20-minute basal, experimental, and recovery periods. Norepinephrine (mixed alpha 1- and alpha 2-agonist) significantly increased intestinal absorption and vascular resistance. Phenylephrine (alpha 1-agonist) significantly increased vascular resistance without altering transport. Clonidine (alpha 2-agonist) stimulated intestinal absorption without changing vascular perfusion pressure. Yohimbine (alpha 2-antagonist) prevented norepinephrine-induced absorption but had no effect on norepinephrine-induced increases in perfusion pressure. In this isolated perfused whole gut model, alpha 1-adrenergic stimulation was responsible for increases in vascular resistance, and alpha 2-adrenergic stimulation was responsible for increases in the absorption of water and electrolytes. The ability to discriminate between alpha 1- and alpha 2-effects has potential therapeutic implications in patients with malabsorption and diarrhea.
 ...
PMID:Discrimination between alpha 1- and alpha 2-adrenergic receptors in the isolated perfused ileum. 289 14

1. A vicious cycle of malabsorption and malnutrition has been implicated in the pathogenesis of protracted diarrhoeal disease in infancy. Vitamin E deficiency is common in malnourished infants with protracted diarrhoea. We have studied the effects of chronic vitamin E deficiency on small-intestinal secretion and absorption in the rat. 2. Weanling rats were fed vitamin E-sufficient or -deficient diets for 21 weeks. Jejunal function was studied in vitro in an Ussing chamber after this period. 3. Steady-state isotopic flux experiments in unstimulated tissues demonstrated net Na+ and Cl- secretion in vitamin E-deficient jejuna but net Na+ and Cl- absorption in vitamin E-sufficient jejuna. 4. Basal intestinal short-circuit current was the same in both groups. 5. Cyclic nucleotide and maximal non-neuronal acetylcholine-mediated electrogenic secretion were increased in vitamin E-deficient jejuna. 6. Exogenous 5-hydroxytryptamine (serotonin) induced a smaller increment in electrogenic secretion in vitamin E-deficient jejuna. 7. Vitamin E-deficient jejuna were less responsive to exogenous noradrenaline, resulting in a smaller alpha 2-adrenergic-mediated decrease in intestinal short-circuit current. 8. Fasting for 72h produced a greater increment in intestinal short-circuit current in vitamin E-deficient jejuna. 9. Chronic vitamin E deficiency is prosecretory in the small intestine and may predispose to the perpetuation of protracted diarrhoeal diseases.
 ...
PMID:Modulation of small-intestinal secretion and absorption in chronic vitamin E deficiency: studies in rat jejunum in vitro. 828 52

Basic guidelines for cancer pain treatment can be found in many different handbooks published in the last years. Particularly those of the World Health Organisation published in 1986 and revised in 1996, furnish useful indication for cancer pain treatment. The authors therefore focused on resuming the most recent development in this field. In the research regarding alternative routes of administration of opioids in alternative to the oral route, the rectal administration of morphine and methadone and the transdermal route for fentanyl have proved to be efficacious. The subcutaneous route (for morphine) as well as the intravenous, peridural and subaracnoid routes, being known for some time are not taken in consideration in this paper. Various studies suggest that alternative routes are necessary in 53-70% of patients in their last days or months of live. The most frequent causes for the need to stop oral administration are dysphagia, nausea, and uncontrollable vomiting, bowel obstruction, malabsorption, cognitive failure, coma, and pain syndromes requiring anaesthetics which need be administered via the spinal route. Among the drugs, tramadol seems to be effective in the control of moderate pain. Tramadol is a centrally acting analgesic drug; it has an agonist effect on mu 1 receptors of opioids and acts also by inhibiting the re-uptake of noradrenaline and serotonine which activates descending monoaminergic inhibitory pathways. Recent clinical studies revealed that pamidronate has an analgesic effect in pain due to bone metastasis. Pamidronate is part of the biphosphonates, which are active on bone metabolism and are usually being used for the treatment of hypercalcaemia in cancer. The authors also describe briefly the indication of ketamin in association with morphine for the treatment of neuropathic pain.
 ...
PMID:[Treatment of pain in oncology]. 923 25

Obesity is reaching epidemic proportions worldwide and it is correlated with various comorbidities, among which the most relevant are diabetes mellitus, arterial hypertension, and cardiovascular diseases. Obesity management is a modern challenge because of the rapid evolution of unfavorable lifestyles and unfortunately there are no effective treatments applicable to the large majority of obese/overweight people. The current medical attitude is to treat the complications of obesity (e.g. dyslipidemia, hypertension, diabetes, and cardiovascular diseases). However, the potential of treating obesity is enormous, bearing in mind that a volitional weight loss of 10 kg is associated with important risk factor improvement: blood pressure -10 mmHg, total cholesterol -10%, LDL cholesterol -15%, triglycerides -30%, fasting glucose -50%, HDL cholesterol +8%. Drug treatment for obesity is an evolving branch of pharmacology, burdened by severe side effects and consequences of the early drugs, withdrawn from the market, and challenged by the lack of long-term data on the effect of medications on obesity-related morbidity and mortality, first of all cardiovascular diseases. In Europe three antiobesity drugs are currently licensed: sibutramine, orlistat, and rimonabant; important trials with clinical endpoints are ongoing for sibutramine and rimonabant. While waiting for their results, it is convenient to evaluate these drugs for their effects on body weight and cardiometabolic risk factors. Sibutramine is a centrally acting serotonin/noradrenaline reuptake inhibitor that mainly increases satiety. At the level of brown adipose tissue, sibutramine can also facilitate energy expenditure by increasing thermogenesis. The long-term studies (five) documented a mean differential weight reduction of 4.45 kg for sibutramine vs placebo. Considering the principal studies, attrition rate was 43%. This drug not only reduces body weight and waist circumference, but it decreases triglycerides and uric acid as well and it increases HDL cholesterol; in diabetics it improves glycated hemoglobin. Sibutramine has conflicting effects on blood pressure: in some studies there was a minimal decrease, in some others a modest increase. In all the studies this drug increased pulse rate. Sibutramine is not recommended in patients with uncontrolled hypertension, or in case of history of cardio- and cerebrovascular disease. Orlistat is a pancreatic lipase inhibitor that reduces fat absorption by partially blocking the hydrolysis of dietary triglycerides. A recent meta-analysis evaluated 22 studies lasting for at least 12 months, in obese patients with a mean body mass index of 36.7 kg/m2, where orlistat was associated with hypocaloric diet or behavioral interventions: the net average weight loss was 2.89 kg (confidence interval 2.27-3.51 kg). Considering the principal studies, attrition rate ranged from 33 to 57%. Orlistat significantly decreases waist circumference, blood pressure, total and LDL cholesterol, but has no effect on HDL and triglycerides. This drug significantly reduced the incidence of diabetes only in subjects with impaired glucose tolerance. The major adverse effects with orlistat are mainly gastrointestinal (fatty and oily stool, fecal urgency, oily spotting, fecal incontinence) and attenuate over time. Orlistat should be avoided in patients with chronic malabsorption and cholestasis. Rimonabant is a selective antagonist of cannabinoid type 1 receptor. This drug, by inhibiting the overactivation of the endocannabinoid system, produces anorectic stimuli at the central nervous level, but also has effects on the peripheral systems involved in metabolism control, such as liver, adipose tissue, skeletal muscles, endocrine pancreas, and gastrointestinal apparatus, influencing many processes partially unknown. An ample experimental program named RIO (Rimonabant In Obesity) involved about 6600 obese or overweight patients to identify the effects of rimonabant in weight loss and associated cardiometabolic abnormalities, over and beyond a caloric restriction of 600 kcal in the treatment and placebo arms. In the four double-blind RIO trials published (Rio-North America, RIO-Europe, RIO-Lipids, RIO-Diabetes), rimonabant 20 mg significantly (p <0.001) reduced weight by 6.3-6.9 kg in the non-diabetic groups vs placebo (-1.5-1.8 kg), whereas in the diabetic subjects enrolled in RIO-Diabetes, weight loss was 5.3 vs 1.4 kg in the placebo group. Attrition rate at 1 year ranged between 40 and 50%, similar to the studies with sibutramine or orlistat. Similarly to weight loss, also waist circumference was significantly reduced by rimonabant. As for cardiometabolic parameters, rimonabant induced a significant increase in HDL cholesterol and a significant decrease in triglycerides. Even if no significant LDL reduction was achieved, the RIO-Lipids study showed a significant decrease in small dense LDL particles, more atherogenic, in rimonabant-treated subjects. Non-diabetic treated patients improved basal insulin and indirect indexes of insulin resistance, while in the RIO-Diabetes study, the only one including diabetics, glycated hemoglobin improved by 0.7% in the active treatment arm vs placebo. The effects on HDL cholesterol and glycated hemoglobin seem in a large percentage unrelated to weight loss. These effects have been confirmed by another trial, named SERENADE, evaluating the treatment in naive diabetic patients. Rimonabant is not recommended in patients with a history of depressive disorders or suicidal ideation and with uncontrolled psychiatric illness, and is contraindicated in patients with ongoing major depression or ongoing antidepressive treatment. In conclusion, despite an enormous advancement in basic research to understand the pathogenetic mechanisms at the base of obesity, the pharmacological research did not reach the therapeutic opportunities available for other chronic conditions, like hypertension and dyslipidemia. However, the few molecules available for clinical practice (sibutramine, orlistat, rimonabant) have shown, when properly used, to contribute to reduce body weight and undoubtedly improve cardiometabolic risk factors. With this preamble, according to current guidelines and pharmacoeconomic studies, patients who might benefit from antiobesity treatment are those with a body mass index > or =30 or 27-29.9 kg/m2 with major obesity-related comorbidities such as hypertension, diabetes, dyslipidemia, obstructive sleep apnea, and metabolic syndrome.
 ...
PMID:[Pharmacological therapy of obesity]. 1877 55