Systemic administration of lipopolysaccharide increases plasma leptin levels: blockade by soluble interleukin-1 receptor

Lipopolysaccharide (LPS) is known to produce several central and neuroendocrine effects and some of these effects are believed to be mediated through cytokines and other proteins. One such protein, leptin, produced by adipose tissue has been shown to cause anorexia, a central effect associated with LPS treatment. This raised the possibility that LPS-induced effects on feeding behavior may be mediated through leptin. This study was done to investigate the effects of systemic administration of LPS on plasma leptin levels in rats and the possible involvement of interleukin-1 (IL-1) in this mechanism. Adult male rats were implanted with indwelling jugular catheters and after collecting two pretreatment blood samples, the animals were injected (i.p.) with saline, 5 microg, 10 microg, or 25 microg/kg BW of LPS, or treated with 25 microg of soluble IL-1 receptor (sIL-1R) 5 min before and 90 min after 25 microg/kg BW of LPS. Posttreatment blood samples were collected at 30 min intervals for a period of 6 h. Plasma leptin concentrations were measured by radioimmunoassay. Treatment with saline did not produce any change in plasma leptin levels. In contrast, each of the three doses of LPS produced a dose-dependent increase in plasma leptin levels within 120 min. Leptin levels remained elevated for the next 4 h. Treatment with sIL-1 R completely blocked the LPS-induced increase in leptin levels, indicating that this effect is in fact mediated through IL-1. These results indicate that leptin could be a possible mediator of LPS-induced effects on feeding.

Malignant fibrous histiocytoma of the pancreas: a case report with genetic analysis

BACKGROUND

Malignant fibrous histiocytoma (MFH) is the most common type of soft tissue sarcoma in adults; it occurs frequently in the extremities, the trunk, or retroperitoneal tissues. MFH rarely is detected in digestive organs, such as the liver or stomach.

METHODS

The authors report a patient with MFH of the pancreas who was treated with surgery alone. The tumor was studied for genetic alterations in the p53, p16ink4a, and DPC4 tumor suppressor genes as well as the K-ras oncogene by immunohistochemistry, single strand conformation variant (SSCV) analysis, and direct DNA sequencing.

RESULTS

The authors believe that this is the 13th report of primary pancreatic MFH in the world literature and the first genetic analysis of this rare tumor. The patient is alive with no evidence of recurrence 34 months after surgery. Immunohistochemistry revealed no abnormal accumulation of the p53 protein and normal nuclear p16 expression. Mutation analysis of the p53, p16, DPC4, and K-ras genes showed only a polymorphism at codon 72 of the p53 gene and no mutations in any of the genes.

CONCLUSIONS

Genotypically, MFH of the pancreas is clearly different from other malignant pancreatic tumors, which further supports the hypothesis that this tumor is a rare but distinct entity.

The effect of thyroid hormone on size of fat depots accounts for most of the changes in leptin mRNA and serum levels in the rat

The physiological consequences and mechanism(s) for thyroid hormone-induced alterations in serum leptin are not known. To address this, leptin expression in rats was evaluated in relationship to food intake, fat mass, and body temperature in rats with pharmacologically altered thyroid status. Total body weight, food intake, and temperature were decreased in hypothyroid rats. Fat weight was decreased in both chronically hypothyroid and hyperthyroid rats (n = 6/group). Serum leptin was linearly correlated with fat weight, epididymal and retroperitoneal fat leptin mRNA concentration, but not total body weight. Serum leptin was decreased in the chronically hyperthyroid rats. When fat weight was used as a covariant, serum leptin was not different between the three groups. Epididymal fat leptin mRNA was higher in euthyroid (n = 7) than in hypothyroid and hyperthyroid rats. Retroperitoneal fat leptin mRNA was not affected by thyroid status. A positive linear relationship between food intake and free triiodothyronine (FT3) index was observed, but not between food intake and serum leptin alone. In a time course study, serum leptin, epididymal fat leptin mRNA content, and fat weight did not change within 24 hours of high-dose triiodothyronine (T3) (n = 6/group), but both temperature and epididymal fat S14 mRNA content rapidly increased. These findings demonstrate that thyroid state influences circulating leptin levels, but primarily does so indirectly through the regulation of fat mass. Leptin does not influence core body temperature across thyroidal state. Finally, thyroid state is more important to regulate food intake, through an as yet undefined mechanism, than are thyroid state-associated changes in serum leptin.

Hypothalamic hypocretin/orexin and neuropeptide Y: divergent interaction with energy depletion and leptin

The aim of this study was to measure the effects of chronic leptin treatment on two orexigenic peptides present in the hypothalamus namely hypocretin/orexin and neuropeptide Y (NPY). For this purpose, recombinant murine leptin (0.2 mg/rat/day) or saline were injected intraperitoneally in Long-Evans rats for 7 consecutive days. Food intake (-8%; p < 0.002) and body weight gain (23.7 +/- 1 vs 31.5 +/- 1.3 g; p < 0.003) were significantly lower in leptin-treated rats than the saline-treated rats. NPY concentrations did not change significantly in any of the microdissected brain areas including the arcuate and paraventricular nuclei. Orexin A concentration in the lateral hypothalamus was significantly decreased by the leptin treatment (-68%; p < 0.01). A smaller decrease (-46%; p < 0.04) was also noted in saline-treated rats pairfed to the level of the leptin-treated rats. We conclude that orexin/hypocretin could be considered as a new relay for leptin in the central nervous system. Its variation in case of lower energy supply observed in pairfed rats could constitute an alerting system for the brain and therefore considered as the first step in the establishment of defense mechanisms against energy depletion.

The insulin receptor--a critical link in glucose homeostasis and insulin action

We have achieved significant progress in understanding the central role of the insulin receptor in an increasingly complicated web of intracellular signal transduction leading to the ultimate biological actions of insulin on glucose, lipid, and other metabolic pathways. The excitement for the future lies not only in clarifying these pathways but also returning to whole-body physiology to readdress basic mechanisms of insulin action in known and novel insulin-sensitive tissues. Hopefully, these new techniques and new perspectives will bring us closer to understanding the pathophysiology of type 2 diabetes mellitus.

Histopathology and physiopathology of gastric mucous hyperplasia in rats heavily infected with Taenia taeniaeformis

Rats heavily infected with larval Taenia taeniaeformis show hyperplasia of the gastric mucosa accompanied by mucous cell proliferation, increase in the level of intragastric pH and hypergastrinemia. Sixty one rats were divided into 2 groups designed as infected (36 rats) and control (25 rats) group. These rats were examined with time course of the infection histopathologically and physiopathologically, during 14-112 days postinfection (DPI). In the infected rats, gastric mucosal hyperplasia began to be observed at 56 DPI, and the structural disturbance of zymogenic units in the corpus and mucous units in the antrum had increased with time. However, the degree of these changes in the antrum was weaker than those in the corpus. Alcianblue and/or PAS-positive cells increased in their numbers with time, and 4 types of cells other than typical surface mucous cell and mucous neck cell were observed by electron-microscopy. However, zymogenic and parietal cells decreased in their number after 56 DPI. Further, the infected rats showed changes in the serum concentration of alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, glucose and total protein. Some similarities with Menetrier's disease were discussed.

The role of the sympathetic nervous system in the regulation of leptin synthesis in C57BL/6 mice

The objectives of this study were to determine whether leptin synthesis is regulated by the sympathetic nervous system and if so whether beta-adrenergic receptors mediate this effect. We show that sympathetic blockade by reserpine increases leptin mRNA levels in brown but not white adipose tissue, while acute cold-exposure decreases leptin expression 10-fold in brown adipose tissue and 2-fold in white adipose tissue. The cold-induced reduction in leptin mRNA can be prevented by a combination of propranolol and SR 59230A but not by either antagonist alone, indicating that beta3-adrenergic receptors and classical beta1/beta2-adrenergic receptors both mediate responses to sympathetic stimulation. Circulating leptin levels reflect synthesis in white adipose tissue but not in brown adipose tissue.

Parathyroids and ultimobranchial bodies in monotremes

Only scant information is available in the scientific literature on the parathyroids and ultimobranchial bodies in the primitive mammals, the echidna (Tachyglossus aculeatus) and platypus (Ornithorhynchus anatinus). The major aim of this paper is to describe the morphology of the monotreme parathyroid gland and to compare it with parathyroids in mammals and reptiles. The gross anatomy and light microscopic structure of the ultimobranchial body, thymus, and thyroid are also given. Animals were dissected and routine light and electron microscopic techniques used to examine the microscopic morphology. The locations of parathyroid hormone, calcitonin and calcitonin gene-related peptide in tissue sections were identified by immunostaining. Monotremes have one pair of parathyroid glands located in the thorax and they are often associated with thymic tissue but never with the thyroid which is also present in the mediastinum. Ultimobranchial bodies are ventrolateral to the commencement of the trachea. Thymic lobules with Hassall's corpuscles are scattered in the fibrofatty tissue of the mediastinum and the ventral surface of the pericardium. Histologically, principal cells, water-clear cells, and non-secretory cells were identified in the parathyroid glands. Principal cells showed polarity and had microlamellar projections that formed intercellular canaliculi. Non-secretory cells had features similar to those of thymic epithelial reticular cells. Immunostaining of parathyroid hormone showed a diffuse distribution in parathyroid principal cells and none in ultimobranchial bodies. Identification of the ultimobranchial bodies was confirmed by immunostaining. The monotreme parathyroid gland, ultimobranchial bodies and thyroid show reptilian as well as mammalian features.

Low calorie diet enhances renal, hemodynamic, and humoral effects of exogenous atrial natriuretic peptide in obese hypertensives

The expression of the natriuretic peptide clearance receptor is abundant in human and rat adipose tissue, where it is specifically inhibited by fasting. In obese hypertensives, plasma atrial natriuretic peptide (ANP) levels were found to be lower than in obese normotensives. Therefore, the increased adipose mass might influence ANP levels and/or its biological activity. The aim of the present study was to evaluate whether the humoral, hemodynamic, and renal effects of exogenous ANP in obese hypertensives might be enhanced by a very low calorie diet. Eight obese hypertensives received a bolus injection of ANP (0.6 mg/kg) after 2 weeks of a normal calorie/normal sodium diet, and blood pressure (BP), heart rate, ANP, cGMP, plasma renin activity, and aldosterone were evaluated for 2 hours before and after the injection. Diuresis and natriuresis were measured every 30 minutes. The patients then started a low calorie/normal sodium diet (510 kcal/150 mmol/d) for 4 days, and then the ANP injection protocol was repeated. The low calorie diet induced a slight weight loss (from 90.6+/-1.1 to 87. 7+/-1.2 kg; P<0.01), which was accompanied by increase of cGMP excretion (from 146.0+/-10.1 to 154.5+/-9.5 nmol/24 h; P<0.05) together with a reduction of BP (P<0.01 versus basal levels). ANP injection after diet was followed by an increase of ANP levels similar to that observed before diet, but plasma cGMP, diuresis, and natriuresis increased significantly only after diet. Similarly, the decrease of BP after ANP administration was significantly higher after diet (change in mean arterial pressure, -6.4+/-0.7 versus -4. 0+/-0.6 mm Hg; P<0.05) as well as that of aldosterone (P<0.01). These data show that a low calorie diet enhances the humoral, renal, and hemodynamic effects of ANP in obese hypertensives and confirm the importance of caloric intake in modulating the biological activity of ANP, suggesting that the natriuretic peptide system can play a role in the acute changes of natriuresis and diuresis associated with caloric restriction.

Focal sensory nerve abnormalities in patients with amyotrophic lateral sclerosis

Slowing of sensory nerve conduction is an unexplained finding in patients with sporadic amyotrophic lateral sclerosis (ALS). To study the frequency of these abnormalities and to study if a predisposition to the development of entrapment neuropathies is causal, 23 patients with definite ALS and 23 age-matched healthy volunteers were investigated prospectively. Antidromic sensory and motor nerve conduction velocities (NCVs) were measured in ulnar and median nerves. Median sensory NCV was abnormally low in three patients if compared with the lower limit of the control group; and median sensory NCV was abnormally low in nine patients (six right, eight left hands) if compared with ipsilateral ulnar sensory NCV. Sensory nerve conduction data did not correlate with clinical findings, such as forearm weakness or usage of canes. Motor nerve conduction data did not correlate with sensory nerve conduction data, with the exception of distal motor latency of right median nerves, which correlated with right median sensory NCV. Our findings show how affection of sensory fibers of distal segments of median nerves can be detected in individual patients with ALS. Nerve entrapment may contribute to this affection, but it is not the only cause. This should be considered in discussions about diagnostic criteria for ALS.

Autoimmune enteropathy

Autoimmune enteropathy (AIE) is an entity reported primarily in infancy, resulting in intractable diarrhea and associated with small bowel villous atrophy and the presence of circulating anti-enterocyte (AEA) antibodies. It is a multisystem disorder with a response, in many cases, to immunosuppressive therapy.

As You Like It, Part 2: A critique and historical review of the electron microscopy literature

As You Like It, Part 2, is a continuation of the lecture given at UltraPath VIII in 1996. It is meant to be a critical historical review of some topics of interest to electron microscopists that will show what went wrong and perhaps also why. Topics are presented under the following headings : (1) Amianthoid Fibers and Giant Collagen Fibrils, (2) Ribosome-Lamella Complex, (3) Globular Filamentous Bodies, and (4) Siderosomes, Hemosiderin vs. Ferritin.

Induction of uncoupling protein expression in brown and white adipose tissue by leptin

Deposition of excess body fat occurs when energy intake chronically exceeds energy expenditure. In ob/ob mice, the absence of leptin affects both components of the energy balance equation, and the mice become morbidly obese after weaning. Treatment of ob/ob mice with exogenous leptin reduces body weight by decreasing food intake and stimulating energy utilization, but even when saline- and leptin-injected ob/ob mice are pair-fed, mice receiving leptin lose significantly more weight. Therefore, the purpose of the present study was to test the hypotheses that uncoupling protein-1 (UCP1) expression is reduced in adipose tissue from ob/ob mice and is restored by treatment with exogenous leptin. Lean and ob/ob mice (5-6 weeks old) were housed at 23 C and treated with leptin (20 microg/g BW x day) for 3 days before they were killed. Compared with levels in lean littermates, UCP1 messenger RNA (mRNA) and protein levels were lower in brown adipose tissue (BAT) and retroperitoneal white adipose tissue (WAT) from ob/ob mice. Treatment of ob/ob mice with leptin reduced body weight and produced a 4- to 5-fold increase in UCP1 mRNA levels in both interscapular BAT and retroperitoneal WAT. The increases in UCP1 mRNA were accompanied by comparable increases in UCP1 protein in mitochondrial preparations from each tissue. Given that the sole known function of UCP1 is to uncouple oxidative phosphorylation, the present results are consistent with the conclusion that leptin stimulates energy utilization in ob/ob mice by increasing thermogenic activity and capacity (UCP1). In addition, the present results suggest that decreased UCP1 expression in BAT and WAT of ob/ob mice is in part responsible for their increased metabolic efficiency and propensity to become obese.

Intracerebroventricular leptin regulates hepatic but not peripheral glucose fluxes

Acute intravenous infusions of leptin markedly alter hepatic glucose fluxes (Rossetti, L., Massillon, D., Barzilai, N., Vuguin, P., Chen, W., Hawkins, M., Wu, J., and Wang, J. (1997) J. Biol. Chem. 272, 27758-22763). Here we examine whether intracerebroventricular (ICV) leptin administration regulates peripheral and hepatic insulin action. Recombinant mouse leptin (n = 14; 0.02 or 1 microgram/kg.h) or vehicle (n = 9) were administered ICV for 6 h to conscious rats, and insulin action was determined by insulin (3 milliunits/kg.min) clamp and tracer dilution techniques. During physiologic hyperinsulinemia (approximately 65 microunits/ml), the rates of glucose uptake (Rd, 20.1 +/- 0.6 and 23.1 +/- 0.7 versus 21.7 +/- 0.6 mg/kg.min; p = NS), glycolysis and glycogen synthesis were similar in rats receiving low- and high-dose leptin versus vehicle. ICV leptin resulted in a 2-3-fold increase in hepatic phosphoenolpyruvate carboxykinase mRNA levels. Glycogenolysis and PEP-gluconeogenesis (2.1 +/- 0.3 mg/kg. min) contributed similarly to endogenous glucose production (GP) in the vehicle-infused group. However, gluconeogenesis accounted for approximately 80% of GP in both groups receiving ICV leptin, while hepatic glycogenolysis was markedly suppressed (0.7 +/- 0.3 and 1.2 +/- 0.3 versus 2.2 +/- 0.4 mg/kg.min, in rats receiving low- and high-dose leptin versus vehicle, respectively; p < 0.01). In summary, short-term ICV leptin administration: 1) failed to affect peripheral insulin action, but 2) induced a striking re-distribution of intrahepatic glucose fluxes. The latter effect largely reproduced that of leptin given systemically at much higher doses. Thus, the regulation of hepatic glucose fluxes by leptin is largely mediated via its central receptors.

Apparent thermogenic effect of injected glucagon is not due to a direct effect on brown fat cells

To examine the significance of brown adipose tissue for the thermogenic response to glucagon, we injected glucagon intraperitoneally into rats (that have glucagon-sensitive brown fat cells) and into hamsters (that have glucagon-insensitive brown fat cells). Although a thermogenic response to glucagon injection was apparently observed in rats, this response was not augmented by cold acclimation and was not dose dependent. Similar observations were made in hamsters. The thermogenic response could be fully blocked by prior injection of the beta-adrenergic blocker propranolol. Thus no direct thermogenic response to injected glucagon could be demonstrated, and the thermogenic response observed was fully due to vehicle injection. However, glucagon injection was able to unmask mitochondrial [3H]GDP binding. As expected, isolated brown fat cells from rats and mice responded thermogenically to glucagon but brown fat cells from hamsters were unresponsive. The EC50 of the rat brown fat cells was high (5 nM); these cells also responded to secretin, with an EC50 of 22 nM. It was concluded that, in contrast to earlier observations, no thermogenic response to injected glucagon could be observed; this may be related to differences in glucagon preparations. Brown fat cells from certain species are, however, glucagon sensitive. It is uncertain whether glucagon is the endogenous agonist for these receptors, but the presence of the glucagon-responsive receptor indicates alternative means to norepinephrine for stimulation of brown adipose tissue thermogenesis and, probably, of recruitment.

Impaired glucose tolerance in mice with a targeted impairment of insulin action in muscle and adipose tissue

Type 2 diabetes is a complex metabolic disorder characterized by peripheral insulin resistance and impaired beta cell function. Insulin resistance is inherited as a non-mendelian trait. In genetically predisposed individuals, resistance of skeletal muscle and adipose tissue to insulin action precedes the onset of clinical diabetes, and is thought to contribute to hyperglycaemia by leading to impaired beta cell function and increased hepatic glucose production. It is not clear whether beta cell and liver defects are also genetically determined. To test the hypothesis that insulin resistance in muscle and fat is sufficient to cause type 2 diabetes in the absence of intrinsic beta cell and liver abnormality, we generated transgenic mice that were insulin-resistant in skeletal muscle and adipose tissue. These mice developed all the prodromal features of type 2 diabetes but, despite the compounded effect of peripheral insulin resistance and a mild impairment of beta cell function, failed to become diabetic. These findings indicate the need for a critical re-examination of the primary site(s) of insulin resistance in diabetes.

Genetic engineering in mice: impact on insulin signalling and action

The expression of a number of genes encoding key players in insulin signalling and action, including insulin, insulin receptor (IR), downstream signalling molecules such as insulin receptor substrate-1 (IRS-1) and IRS-2, glucose transporters (GLUT4, GLUT2) and important metabolic enzymes such as glucokinase, has now been altered in transgenic or knockout mice. Such mice presented with phenotypes ranging from mild defects, revealing complementarity between key molecules or pathways, to severe diabetes with ketoacidosis and early postnatal death. Insulin action could also be improved by overproduction of proteins acting at regulatory steps. The development of diabetes by combining mutations, which alone do not lead to major metabolic alterations, validated the 'diabetogenes' concept of non-insulin-dependent diabetes mellitus. Genes encoding insulin-like growth factors (IGF-I and IGF-II) and their type I receptor (IGF-IR) have also been disrupted. It appears that although IR and IGF-IR are both capable of metabolic and mitogenic signalling, they are not fully redundant. However, IR could replace IGF-IR if efficiently activated by IGF-II. Studies with cell lines lacking IR or IGF-IR lend support to such conclusions. Concerning the issues of specificity and redundancy, studies with cell lines derived from IRS-1-deficient mice showed that IRS-1 and IRS-2 are also not completely interchangeable.

Sympathetic skin response in amyotrophic lateral sclerosis

OBJECTIVES

The aim of our study was to verify the usefulness of the sympathetic skin response (SSR) as an instrument for assessing autonomic involvement in amyotrophic lateral sclerosis (ALS).

MATERIAL AND METHODS

- We studied palmar and plantar SSR in 31 patients with ALS (mean age: 58.4+/-9.3 years); 48 age-matched healthy subjects constituted the control group.

RESULTS

Palmar SSR was elicitable in all patients, and its latency and amplitude did not significantly differ from that of the controls. Plantar response was evoked in all but 7 patients. The lack of response was significantly related to the functional disability and duration of the disease.

CONCLUSIONS

We conclude that SSR, even the plantar response, cannot be considered a useful tool for detecting early autonomic involvement in ALS.

Differential regulation of uncoupling protein gene homologues in multiple tissues of hibernating ground squirrels

Nonshivering thermogenesis in brown adipose tissue (BAT) provides heat through activation of a mitochondrial uncoupling protein (UCP1), which causes futile electron transport cycles without the production of ATP. Recent discovery of two molecular homologues, UCP2, expressed in multiple tissues, and UCP3, expressed in muscle, has resulted in investigation of their roles in thermoregulatory physiology and energy balance. To determine the expression pattern of Ucp homologues in hibernating mammals, we compared relative mRNA levels of Ucp1, -2, and -3 in BAT, white adipose tissue (WAT), and skeletal muscle of arctic ground squirrels (Spermophilus parryii) hibernating at different ambient and body temperatures, with levels determined in tissues from ground squirrels not in hibernation. Here we report significant increases in mRNA levels for Ucp2 in WAT (1. 6-fold) and Ucp3 in skeletal muscle (3-fold) during hibernation. These results indicate the potential for a role of UCP2 and UCP3 in thermal homeostasis during hibernation and indicate that parallel mechanisms and multiple tissues could be important for nonshivering thermoregulation in mammals.

Sensory nerves affect the recruitment and differentiation of rat periovarian brown adipocytes during cold acclimation

Rat periovarian adipose tissue contains a low number of uncoupling protein-expressing brown adipocytes scattered into lobules of white fat. Their increase following cold acclimation is matched by a major increase in noradrenergic and neuropeptide Y-, substance P- and calcitonin gene-related peptide-containing nerves. To ascertain whether periovarian fat is provided with sensory nerves, and whether any relationship exists between such nerves (in particular the calcitonin gene-related peptide-containing fibers found in cold-acclimated rats in close association with brown adipocytes) and brown fat recruitment, the effects of capsaicin desensitization on neuropeptide-containing nerves and brown adipocyte density were studied in the periovarian tissue of rats kept at 20 degrees C and on a group acclimated to 4 degrees C for 14 days. In both groups, systemic capsaicin administration considerably reduced the expression of substance P and calcitonin gene-related peptide in vascular-nerve bundles and parenchyma. In cold-acclimated rats, the increase in brown adipocyte density was significantly checked by capsaicin administration (21.11 versus 7.96 brown adipocytes/mm2, P<0.05). Finally, ultrastructural investigation showed the occurrence of brown adipocyte precursors filled with aggregates of glycogen and poorly differentiated multilocular adipocytes in capsaicin-treated cold-acclimated rats. These data suggest that periovarian adipose tissue is indeed provided with sensory neuropeptide-containing nerves and that they play a role in the recruitment and differentiation of brown adipocytes.

Hormonal and neuroendocrine regulation of energy balance--the role of leptin

A new dimension to the regulation of energy balance has come from the identification of the ob (obese) gene and its protein product, leptin. Leptin is produced primarily in white adipose tissue, but synthesis also occurs in brown fat and the placenta. Several physiological functions have been described for leptin the inhibition of food intake, the stimulation/maintenance of energy expenditure, as a signal of energy reserves to the reproductive system, and as a factor in haematopoiesis. The production of leptin by white fat is influenced by a number of factors, including insulin and glucocorticoids (which are stimulatory), and fasting, cold exposure and beta-adrenoceptor agonists (which are inhibitory). A key role in the regulation of leptin production is envisaged for the sympathetic nervous system, operating through beta 3-adrenoceptors. The leptin receptor gene is expressed in a wide range of tissues, and several splice variants are evident. A long form variant (Ob-Rb) with an intracellular signalling domain is found particularly in the hypothalamus. Leptin exerts its central effects through neuropeptide Y, and through the glucagon-like peptide-1 and melanocortin systems, but it may also interact with other neuroendocrine pathways. The role and function of the leptin system in agricultural animals has not been established, but it offers a potential new target for the manipulation of body fat.

Infant cold exposure changes Fos expression to acute cold stimulation in adult hypothalamic brain regions

It is known that cold exposure as an infant results in a permanent cold tolerance which is accompanied by a reduced rate of colonic temperature decline and increased metabolic heat production to cold stimulation. The present study was aimed to elucidate the central mechanism of cold tolerance of adult rats with cold exposure as infants. Newborn infants were exposed to cold ambient (4 degrees C) daily for 2 weeks, and when they were 15-weeks old, Fos expression to acute cold stimulation (10 degrees C) in whole brain regions was investigated using quantitative immunohistochemistry. Acute cold stimulation induced a significant increase of Fos-positive neurons in many nuclei of whole brain areas in adult rats both with and without cold exposure as infants. However, the number of Fos-positive neurons was significantly less in the rats with cold exposure than without cold exposure as infants, particularly in the hypothalamic nuclei such as the lateral septal nucleus (LS), preoptic area (POA), parvocellular paraventricular nucleus (pPVN0, ventromedial hypothalamic nucleus (VMH) and supramammillary nucleus (SuM). However, there was no significant difference in the number of Fos-positive neurons in the extra-hypothalamic regions between the rats with and without cold exposure as infants. These results suggest that the central mechanism of cold tolerance with cold exposure as infants is due to metabolic changes of the hypothalamic brain regions.

Hyperleptinaemia in mice induced by administration of the tyrosine hydroxylase inhibitor alpha-methyl-p-tyrosine

Alpha-methyl-p-tyrosine (alphaMPT), an inhibitor of tyrosine hydroxylase, was administered to mice to block noradrenaline synthesis. Ten hours after injection of alphaMPT there was a 6-fold increase in plasma leptin. The level of ob mRNA in epididymal white adipose tissue was also increased, but UCP1 mRNA in brown fat fell. In contrast to lean mice, ob mRNA in white fat of ob/ob mice was not increased by alphaMPT. AlphaMPT raised plasma leptin in fasted as well as fed mice. Hyperleptinaemia was attenuated by treatment with a beta3-adrenoceptor agonist. Inhibition of noradrenaline synthesis leads to the rapid induction of hyperleptinaemia; it is suggested that sympathetic tone plays a pivotal role in regulating leptin production.

Insulin and insulin-like growth factor-I receptor mediated differentiation of 3T3-F442A cells into adipocytes: effect of PI 3-kinase inhibition

The ability of insulin and insulin-like growth factors (IGF-I and IGF-II) to induce differentiation of 3T3-F442A cells into adipocytes was examined at various hormone concentrations. Both insulin and the IGFs promoted differentiation at concentrations compatible with binding to their cognate receptors, suggesting that both insulin and IGF-I receptors are capable of promoting this differentiation. Adipocyte conversion of 3T3-F442A cells was completely blocked in the presence of LY294002, a specific inhibitor of PI 3-kinase, indicating that PI 3-kinase activity plays a crucial role in the initial signalling events that trigger this differentiation process.

Intradural spinal hibernoma: case report

BACKGROUND

Hibernoma is a rare, benign tumor arising from vestigial remnants of brown adipose tissue. It usually affects muscle and subcutaneous tissue and is asymptomatic and slow growing.

METHODS

A review of the worldwide literature contains about 110 cases of hibernomas. However, only two cases (including our case) of hibernoma located in the intradural spine have been reported. We present an extremely rare case of intradural extramedullary spinal hibernoma and summarize the magnetic resonance imaging (MRI) findings of the lesion.

CASE DESCRIPTION

A 35-year-old woman suffered from motor weakness and numbness of the left upper extremity. Cervical spinal MRI revealed an intradural extramedullary mass at C7. She underwent surgery via the posterior approach and the lesion was completely removed. Histopathologic examination showed multivacuolated cells with centrally placed nuclei, and the diagnosis of hibernoma was made.

CONCLUSIONS

Because the CT and MRI findings of hibernoma are almost same as those of other lipomatous tumors, a surgical specimen of this tumor is necessary to establish the correct diagnosis. Early diagnosis and total resection are necessary as some cases showed malignant features or rapid growth. Etiologically, the tumor may have developed by the ectopic growth or migration of adipose tissue.

Nerve growth factor, beta3-adrenoceptor and uncoupling protein 1 expression in rat brown fat during postnatal development

An analysis was made of the expression of nerve growth factor (NGF) mRNA and protein in the brown fat of rats at different ages, and the results compared with the expression of beta3-adrenoceptor and uncoupling protein 1 (UCP1). NGF, beta3-adrenoceptor, and UCP1 messenger RNA and protein levels were measured by means of reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting in the brown fat of rats at different ages (from 20-day-old fetuses (E20) to 16-month-old rats). During the perinatal period, NGF production increased and then declined to adult levels (which are comparable with fetal levels) by eight months, and remained stable thereafter. Relatively low levels of NGF were present in the brown fat of aged rats. Taken together, these results suggest that NGF may be responsible for regulating sympathetic innervation during the perinatal and adult periods.

beta 3-Adrenergic agonist induces a functionally active uncoupling protein in fat and slow-twitch muscle fibers

The mitochondrial uncoupling protein (UCP) has usually been found only in brown adipose tissue. We recently observed that a chronic administration of the beta 3-adrenergic agonist CL-316,243 (CL) induced the ectopic expression of UCP in white fat and skeletal muscle in genetic obese yellow KK mice. The aim of the present study was to examine whether UCP could be induced in nongenetic obese animals produced by neonatal injections of monosodium L-glutamate (MSG). The daily subcutaneous injection of CL (0.1 mg/kg) to MSG-induced obese mice for 2 wk caused significant reductions of body weight (15%) and white fat pad weight (58%). Northern and Western blot analyses showed that CL induced significant expressions of UCP in the white fat and muscle, as well as in brown fat. Immunohistochemical observations revealed that the UCP stains in white fat were localized on multilocular cells and that those in muscle were localized on slow-twitch fibers rich in mitochondria. Immunoelectron microscopy confirmed the mitochondrial localization of UCP in the myocytes. The guanosine 5'-diphosphate (GDP) binding to mitochondria in brown fat doubled after the CL treatment. Moreover, significant GDP binding was detected in the white fat and muscle of the CL-treated mice, at about one-fourth and one-thirteenth the activity of brown fat, respectively, suggesting that ectopically expressed UCP is functionally active. We concluded that the beta 3-adrenergic agonist CL can induce functionally active UCP in white fat and slow-twitch muscle fibers of obese mice.

Syndrome of intractable diarrhoea with persistent villous atrophy in early childhood: a clinicopathological survey of 47 cases

BACKGROUND

The syndrome of intractable diarrhoea of infancy is heterogeneous and includes several diseases with diverse aetiologies. This study determines whether diagnostic categories can be defined on the basis of clinicopathological analysis.

METHODS

European Society of Paediatric Gastroenterology, Hepatology and Nutrition members were surveyed to identify cases of intractable diarrhoea with persisting small intestinal enteropathy. A retrospective clinicopathological analysis was performed on cases showing life-threatening diarrhoea within the first 24 mo of life and requiring total parenteral nutrition, which were characterized by persistent villous atrophy, and resistance to therapy.

RESULTS

Forty-seven infants were identified with intractable diarrhoea. Villous atrophy was of varying degrees with (group I, n = 24) or without (group II, n = 18) lamina propria mononuclear cell infiltration. Group I presented later, had gut autoantibodies, and a higher prevalence of protein-losing enteropathy; a subset (group Ia, n = 12) also had extraintestinal symptoms of autoimmunity associated with a later onset of larger volume diarrhoea. Group II presented early; 8 cases (group IIa) had phenotypic abnormalities and a low birth weight; the remaining 10 (group IIb) showed mild-to-moderate villous atrophy, epithelial tufting, and abnormal crypts. Group III included five patients in whom no specific features were recognised. Twenty-one (45%) died at a median age of 24 months, 20 (43%) remained dependent on parenteral (n = 16) or enteral tube (n = 4) feeding, 4 (9%) received elimination diets plus other therapies, and 2 (4%) were lost to follow-up.

CONCLUSIONS

Clinicopathological analysis allowed distinct disease groups to be identified, allowing a provisional classification to be made. This straightforward approach forms a basis for future research in this exceptionally difficult paediatric condition.

Growth and function of human parathyroid tissue transplanted to athymic mice

The morphology, cell proliferation and function of transplanted normal, hyperplastic and adenomatous human parathyroid tissue was studied after transplantation to athymic mice. The iPTH was evaluated in relation to morphology. Human parathyroid tissue collected during surgery for hyperparathyroidism was implanted subcutaneously into athymic mice (nu/nu-BALB/cA) and was analysed 1, 4, 7 and 12 weeks after transplantation. The transplants were examined by light and electron microscopy and by autoradiography after continuous infusion of 3H-thymidine. The relative amount of viable tissue was evaluated using a computer image analysing programme. Graft function was evaluated by measuring human iPTH in mouse serum. A transplant take ratio of 93% was observed. The proliferation rate in adenoma grafts at 12 weeks after transplantation was five and fifteen times that observed in normal and hyperplastic transplants, respectively. In normal and adenoma groups, a continuous increase in iPTH concentrations was observed, but in the hyperplastic group the iPTH remained on the same level. The secretion of iPTH in relation to the amount of transplanted tissue and the fraction of viable tissue was at the same level at 12 weeks in normal and adenomatous grafted animals. In conclusion, human parathyroid tissue was successfully transplanted and maintained its original structure. The growth potential, but not the iPTH secretion, was significantly higher in adenoma grafts compared to grafts from hyperplastic and normal glands.

Plasma atrial natriuretic peptide and natriuretic peptide receptor gene expression in adipose tissue of normotensive and hypertensive obese patients

OBJECTIVE

Human and rat adipose tissue contain very high levels of natriuretic peptides clearance receptor messenger (m)RNA, and fasting inhibits its gene expression in adipose tissue. In this study we evaluated plasma atrial natriuretic peptide (ANP) and gene expression of biologically active type A natriuretic peptide receptor (NPr-A) and clearance natriuretic peptide receptor (NPr-C) in adipose tissue of obese hypertensive and obese normotensive patients.

DESIGN AND METHODS

We studied 27 untreated obese hypertensives, 26 obese normotensives (body mass index > or = 30 kg/m2), 24 non-obese essential hypertensives and 23 lean healthy subjects (body mass index < or = 25 kg/m2). Blood samples were withdrawn for ANP, plasma renin activity and aldosterone radioimmunoassays. Subcutaneous peri-umbilical adipose tissue samples were obtained, by needle aspiration, in 13 obese hypertensives and in 12 obese normotensives and used for RNA extraction. Then, complementary synthesis and semiquantitative polymerase chain reaction (PCR) with primers complementary to sequences of different exons of the genes encoding for NPr-A, NPr-C and beta-actin, were performed. 32P-labeled PCR products were separated by electrophoresis, blotted onto nylon membranes, and the exposed autoradiographic films were analysed by densitometry. NPr signals were normalized by the beta-actin expression level.

RESULTS

Plasma ANP was lower in obese hypertensives than in obese normotensives (37.5+/-7 versus 43.2+/-6 pg/ml, P< 0.05), but was higher in non-obese hypertensives than in non-obese normotensives. In contrast, plasma renin activity and aldosterone were higher in the obese hypertensives. Although NPr-A and NPr-C expression were not statistically different between the two obese groups, the NPr-A: NPr-C mRNA ratios were significantly lower in obese hypertensives (P < 0.03).

CONCLUSIONS

Our data suggest that in obese hypertensives compared to obese normotensives, the lower NPr-A: NPr-C ratio might determine decreased biological activity and/or an increased clearance of natriuretic peptide in adipose tissue, suggesting that the natriuretic peptide and its receptor system may be important in obesity-related hypertension where ANP levels are lower.

The leptin receptor mediates apparent autocrine regulation of leptin gene expression

The possibility that the leptin receptor (LEPR) mediates autocrine regulation of leptin expression in adipose tissue was examined in 10-day-old Zucker rat pups with different copy numbers of the leptin receptor mutation (Lepr(fa)). Plasma leptin concentrations and adipose tissue mRNA levels for leptin were related to copy number of the mutation (fa/fa > fa/+ > +/+). These relationships were independent of plasma insulin concentration. Reduced copy number for the functional leptin receptor apparently results in a diminished negative feedback signal to the leptin gene in adipose tissue. Thus, leptin appears to close a short regulatory loop controlling its own synthesis in adipose tissue.

The ultrastructure of liposarcomas with attention to "dedifferentiation"

Liposarcomas are among the most common soft tissue sarcomas. It is recognized that dedifferentiation can occur within a well-differentiated liposarcoma, but there is limited information concerning the ultrastructure of the dedifferentiated cells. A series of 8 cases has been studied by light and electron microscopy and compared with well-differentiated, myxoid, and pleomorphic liposarcomas. No definite evidence of lipoblastic differentiation could be found in the dedifferentiated cases. The tumor cells resembled atypical cells in the well-differentiated liposarcomas, supporting the close relationship between these two types of tumors. However, since no conclusive line of differentiation could be found in the dedifferentiated cases, this study supports the contention that these neoplasms are undifferentiated counterparts of well-differentiated liposarcomas.

Tissue distribution and localization of natriuretic peptide receptor subtypes in stroke-prone spontaneously hypertensive rats

OBJECTIVE

To investigate tissue distribution and localization of the natriuretic peptide receptor (NPR) subtypes' messenger RNA (mRNA) and to compare their expression between stroke-prone spontaneously hypertensive rats (SHR-SP) and Wistar-Kyoto (WKY) rats.

METHODS

Total RNA was extracted from organs of SHR-SP and WKY rats aged 13 weeks. The mRNA level was examined by RNase protection assay. The localization of the transcripts was determined by in-situ hybridization.

RESULTS

In SHR-SP aged 13 weeks, NPR-A was expressed most abundantly in the adrenal gland, lung and aorta, in that order. NPR-B was expressed highly in the uterus and ovary, and also in the lung, adrenal, and brain. NPR-C was expressed predominantly in the atrium and mesentery, less so in the lung, vein, and kidney. In the adrenal gland, NPR-A was expressed mainly in zona glomerulosa cells. In the atrium, NPR-C was expressed throughout the wall. In the mesentery, NPR-C mRNA was detected mainly in adipocytes. In the kidney, NPR-C was found predominantly in podocytes. Whereas the levels of expression of NPR subtypes in most tissues examined did not differ between SHR-SP and WKY rats, the NPR-C mRNA level was significantly greater in the kidneys of SHR-SP than it was in those of WKY rats.

CONCLUSIONS

These results indicated that each NPR subtype had a distinct tissue distribution pattern and that the expression of NPR-C in the kidneys of SHR-SP was greater than that in the kidneys of WKY rats.

Short term effects of leptin on hepatic gluconeogenesis and in vivo insulin action

Long term administration of leptin decreases caloric intake and fat mass and improves glucose tolerance. Here we examine whether leptin acutely regulates peripheral and hepatic insulin action. Recombinant mouse leptin (0.3 mg/kg.h, Leptin +) or vehicle (Leptin -) were administered for 6 h to 4-month-old rats (n = 20), and insulin (3 milliunits/kg.min) clamp studies were performed. During physiologic hyperinsulinemia (plasma insulin approximately 65 microunits/ml), the rates of whole body glucose uptake, glycolysis, and glycogen synthesis and the rates of 2-deoxyglucose uptake in individual tissues were similar in Leptin - and Leptin +. Post-absorptive hepatic glucose production (HGP) was similar in the two groups. However, leptin enhanced insulin's inhibition of HGP (4.1 +/- 0.7 and 6.2 +/- 0.7 mg/kg.min; p < 0.05). The decreased HGP in the Leptin + group was due to a marked suppression of hepatic glycogenolysis (0.7 +/- 0.1 versus 4.1 +/- 0.6 mg/kg.min, in Leptin + versus Leptin -, respectively; p < 0.001), whereas the % contribution of gluconeogenesis to HGP was markedly increased (82 +/- 3% versus 36 +/- 4% in Leptin + and Leptin -, respectively; p < 0.001). At the end of the 6-h leptin infusion, the hepatic abundance of glucokinase mRNA was decreased, whereas that of phosphoenolpyruvate carboxykinase mRNA was increased compared with Leptin -. We conclude that an acute increase in plasma leptin 1) enhances insulin's ability to inhibit HGP, 2) does not affect peripheral insulin action, and 3) induces a redistribution of intrahepatic glucose fluxes and changes in the gene expression of hepatic enzymes that closely resemble those of fasting.

Folliculo-stellate cells and intercellular communication within the rat anterior pituitary gland

Folliculo-stellate (FS) cell are agranular and arranged around a follicle. They contain the S-100 protein and beta-adrenergic receptors. It has been suggested that they can act as stem cells, since they show mitotic figures, and could transform into granular or chromophilic cells according to the concept of a "cell renewal system." Cell-to-cell interactions among pituitary cells have been described, and recent progress with freeze-fracture electron microscopy has provided novel observations of the cell surface and gap junctions within the rat or teleost fish pituitary gland, or in cultured rat pituitary cells. In adult rats, the anterior pituitary was composed of lobules incompletely separated by a basement membrane. Follicles consisted exclusively of FS cells. Gap junctions were observed only between adjacent FS cells, in rare cases on the tips of their cytoplasmic processes. Thus, the FS cells, connected by gap junctions, made up a dense cellular network throughout the pituitary. Gap and tight junctions were absent on granular cells. Elongated follicles with columnar FS cells were observed in 10-day-old rats and were separated into smaller units. The number of gap junctions rapidly increased with age until 40-45 days of age. Few S-100 protein positive cells were observed on day 10, along the marginal cell layer and near the so-called postero-lateral wing. The frequency of positive cells increased with age and by day 40; numerous cells were observed throughout the anterior lobe. Gap junction number also varied with the stage of the estrous cycle, and frequency; during diestrus, they were half of that during proestrus or estrus. The number of gap junctions increased in late pregnancy and in lactating rats, probably due to changes in estrogen and progesterone. Hormone (LH-RH and testosterone) treated groups of rats showed accelerated development by almost 10 days, compared with controls. In castrated male rats, the ultrastructure of the pituitary remained immature even at 40 days of age, when the number of gap junctions was a quarter or less than the number in intact rats. Testosterone treatment restored the frequency of gap junctions to a normal level. We conclude that the appearance of gap junctions in the pituitary cells and maturation of the gland are dependent to a large degree upon gonadal steroids.

Insulin stimulates both leptin secretion and production by rat white adipose tissue

Leptin, the peptide encoded by the obese gene, is secreted by adipose cells and plays a role in regulating food intake, energy expenditure, and adiposity. Because earlier studies suggested that insulin increases the expression of leptin, we investigated the effect of insulin on leptin secretion by adipose tissue. Epididymal fat pads were incubated in vitro in the presence or absence of insulin over a 4-h time course. Insulin increased leptin secretion by about 80% at all time points studied. After 10 min of insulin treatment, the amount of tissue-associated leptin was lower in insulin-stimulated tissue, presumably due to the increased secretion. At later times, both tissue-associated leptin and total leptin production were higher in insulin-treated tissue. In untreated, isolated adipose cells, immunostaining of leptin was detected in the endoplasmic reticulum by confocal microscopy. After insulin treatment, there were two populations of cells. In many cells, leptin staining became fainter and was restricted to a narrow band near the plasma membrane. However, in other cells the leptin-staining pattern was unchanged. Leptin did not colocalize with GLUT4, the glucose transporter isoform found primarily in insulin-responsive cells, in either basal or insulin-stimulated adipose cells. In this study, insulin increased both secretion and production of leptin by adipose tissue fragments. Interestingly, insulin appeared to stimulate the transport of leptin from the endoplasmic reticulum rather than acting on a pool of regulated secretory vesicles. (Endocrinology 138: 4463-4472, 1997)

S-100 proteins in trimethyltin-induced neurodegeneration in the rat hippocampus. An immunochemical and immunocytochemical study

After acute trimethyltin (TMT) intoxication (21 d after a single i.p. injection at a dose of 8 mg/kg) the histological, immunohistochemical, and immunochemical investigation of adult rat hippocampus showed a distinct pattern of neuronal loss, and an increase in both glial fibrillary acidic protein- (GFAP) immunoreactive cells and GFAP concentration, as expected. S-100-immunoreactive cells also increased markedly, whereas the concentration of S-100 increased even more than that of GFAP. The data show that S-100 is an index of glial reaction to damage after TMT intoxication and suggest the potential usefulness of exploring the possibility that it may play a role in induced neurodegenerative processes.

Targeted gene disruption reveals a leptin-independent role for the mouse beta3-adrenoceptor in the regulation of body composition

Targeted disruption of mouse beta3-adrenoceptor was generated by homologous recombination, and validated by an acute in vivo study showing a complete lack of effect of the beta3-adrenoceptor agonist CL 316,243 on the metabolic rate of homozygous null (-/-) mice. In brown adipose tissue, beta3-adrenoceptor disruption induced a 66% decrease (P < 0.005) in beta1-adrenoceptor mRNA level, whereas leptin mRNA remained unchanged. Chronic energy balance studies in chow-fed mice showed that in -/- mice, body fat accumulation was favored (+41%, P < 0.01), with a slight increase in food intake (+6%, NS). These effects were accentuated by high fat feeding: -/- mice showed increased total body fat (+56%, P < 0.025) and food intake (+12%, P < 0.01), and a decrease in the fat-free dry mass (-10%, P < 0.05), which reflects a reduction in body protein content. Circulating leptin levels were not different in -/- and control mice regardless of diet. The significant shift to the right in the positive correlation between circulating leptin and percentage of body fat in high fat-fed -/- mice suggests that the threshold of body fat content inducing leptin secretion is higher in -/- than in control mice. Taken together, these studies demonstrate that beta3-adrenoceptor disruption creates conditions which predispose to the development of obesity.

Acquired motor neuron disorders

The acquired motor neuron disorders are a heterogeneous group of conditions in which motor neuron degeneration or dysfunction produces the predominant manifestation of weakness, while the sensory system is clinically spared. The disorders most commonly seen in clinical practice are amyotrophic lateral sclerosis, late manifestations of poliomyelitis, and lower motor neuron syndromes, including motor neuropathy. Less often, acquired motor neuron disorders may complicate metabolic, toxic, or systemic disorders. The pathogenesis of most acquired motor neuron disorders is poorly understood, and treatment is mainly supportive; however clues to understanding the pathogenesis of amyotrophic lateral sclerosis are emerging, and new pharmacologic therapies are available. There is a growing sense of hope that combinations of drugs that are currently being tested may impact the survival of amyotrophic lateral sclerosis.

An abnormal relationship between blood pressure and pulse rate in amyotrophic lateral sclerosis

OBJECTIVES

To clarify the autonomic dysfunctions in amyotrophic lateral sclerosis (ALS) patients, we investigated the relationship between blood pressure (BP) and pulse rate (PR), QTc interval, and coefficient of variation in the R-R interval (CVR-R) in ALS patients.

MATERIALS AND METHODS

BP and PR were determined automatically every 30 min for 24 h in 6 patients with ALS and in 18 healthy age-matched volunteers. The QTc interval and CVR-R were also evaluated using an electrocardiogram.

RESULTS

The relationship between BP and PR was lost in the ALS group. There was no significant difference in the QTc interval or CVR-R between the ALS and control groups.

CONCLUSION

We speculate that the imbalance between BP and PR observed in the ALS group reflects a disorder in the balance between the sympathetic and parasympathetic nervous systems.

Autoimmune enteropathy and villous atrophy in adults

BACKGROUND

Autoimmune enteropathy is a condition described in children and characterised by villous atrophy, which is unresponsive to any dietary restrictions, and by the presence of enterocyte autoantibodies. We report two adult patients who fulfilled all the criteria for the diagnosis of this disorder.

METHODS

Over the past 5 years we have seen four adult patients (all women, median age 51.5 [range 38-64] years) with subtotal villous atrophy, which was unresponsive to a gluten-free diet. The patients were HLA-DQ2 positive. IgA antigliadin and antiendomysial antibodies were not found in any of the patients. We did an indirect immunofluorescence search for enterocyte autoantibodies on monkey jejunum and for other autoantibodies for all four patients.

FINDINGS

Of the four patients, two were positive for enterocyte autoantibodies and one of these two patients was positive for antiactin, antiparietal cell, and antithyroid microsomal autoantibodies.

INTERPRETATION

To the best of our knowledge the two patients affected by severe enteropathy, who had never responded to any exclusion diet, and who were positive for enterocyte autoantibodies are the first cases of autoimmune enteropathy described in adults. We propose that adult patients whose disorders are unresponsive to a gluten-free diet should be tested for enterocyte autoantibodies.