Can early clinical parameters predict post-traumatic pituitary dysfunction in severe traumatic brain injury?

BACKGROUND: Post-traumatic hypopituitarism is a major complication after severe head trauma. The aim of our study was to evaluate the possible role of early clinical parameters in the development of endocrine deficits. METHODS: Data on endocrine function, on-admission clinical-, laboratory-, and ICU-monitored parameters were available in 63 patients of the surviving 86 severe head injury patients (post-resuscitation GCS under 8) treated at one neurosurgical center during a 10-year period. RESULTS: Hypopituitarism was diagnosed in 68.3 % of the patients. The most frequently affected pituitary axis was the growth hormone (GH): GH deficiency or insufficiency was present in 50.8 %. Central hypogonadism affected 23.8 % of male patients; hypothyroidism and secondary adrenal failure were found in 22.2 and 9.5 % of the investigated population, respectively. Early onset (within 1 year of brain injury) hypopituitarism was found in 24 patients. No connection was found between the development of hypopituitarism and any of the clinical parameters assessed on-admission or at ICU. Significant correlations were found between early endocrine dysfunctions and surgical intervention (OR: 4.64) and the diagnosis of subdural hematoma (OR: 12). In our population, after road traffic accidents, the development of late-onset hypopituitarism was less prevalent (OR: 0.22). CONCLUSIONS: Since our results do not indicate any reliable predictive parameter for the development of endocrine dysfunction in a cohort of patients with severe traumatic brain injury, regular endocrine screening of this specific patient population seems obligatory.

Atropine-induced gastrointestinal cytoprotection dependences to the intact of vagal nerve against indomethacin-induced gastrointestinal mucosal and microvascular damage in rats.

UNLABELLED: The non-steroidal antiinflammatory drugs, such as an indomethacin (IND), cause mucosal ulceration and increase the mucosal vascular permeability in the gastrointestinal (GI) tract. Some exogenous agents, e.g. the atropine, can protect the GI mucosa against these ulcerogenic effects. The gastrointestinal functions and mucosal protection, however, are regulated by the vagal nerve. The aims of this study was to examine the dependence of atropine-induced GI cytoprotection to the vagal innervation against the development of IND-caused ulcers and microvascular damage in the mucosa of stomach and small intestine in rats. METHODS: the observations were carried out on CFY-strain rats. The mucosal damage was produced by subcutaneous administration of IND in a 20 mg/kg dose 24 h prior to the killing of animals at the same time as the start of atropine-application, which was given in a small dose (0.1 mg/kg) every 5 h. The subdiaphragmatic bilateral surgical vagotomy was done 24 h before the experiment. The vascular permeability, indicated by the microvascular endothel damage, was measured by the appearance and concentration of intravenously administered Evans blue into the GI mucosa. The number and severity of mucosal lesions and the Evans blue content of mucosa were determined in the stomach and small intestine. RESULTS: (1) The IND caused mucosal ulcers and Evans blue extravasation into the mucosa of the stomach and small intestine. (2) The IND-induced mucosal ulceration and vascular permeability significantly decreased after atropine-administration in the same parts of GI tract. (3) The extent of cytoprotective effect of atropine against the IND was decreased after bilateral surgical vagotomy. CONCLUSIONS: (1) The IND causes microvascular endothel damage in the stomach and small intestinal. (2) The atropine has a cytoprotective effect in the stomach and small intestine against the aggressive effects of IND without decrease of gastric acid secretion. (3) The intact vagal nerve is necessary to the function of cytoprotective mechanisms of atropine against the IND.

Active water selective channels in the stomach: investigation of aquaporins after ethanol and capsaicin treatment in rats.

UNLABELLED: Recent studies discovered the existence of aquaporins (AQP), suggesting their roles in the active, ATP dependent water secretion or absorption. Our recent development of the monoclonal antibody family against aquaporins (Type 1 and 4) allowed us a good opportunity to investigate the mechanism of the gastric mucosal edema in a rat model. THE AIM OF OUR STUDY was to evaluate the changes in the tissue level of aquaporins (AQP1 and AQP4) after ethanol and capsaicin treatment in rat stomach. MATERIALS AND METHODS: the experiments were carried out on Sprague-Dawley rats weighing 150-200 g. The animals were fasted for 24 h, after the 1 ml of ethanol (50% v/v) or capsaicin (2 mg/ml) was given intragastrically. Rats were sacrificed after 5, 30, 60, 120 and 240 min, the tissue level of AQP1 and AQP4 was investigated immunoserologically by ELISA and dot-blot methods using our monoclonal antibodies. The location of these aquaporins in the gastric tissue was demonstrated by immunohistochemistry. RESULTS: (1) in ethanol-treated stomach, both AQP1 and AQP4 increased after 5 min simultaneously with gastritis, then decreased dramatically depending on time. (2) In the capsaicin-treated group there were no changes in the tissue level of aquaporins in the first hour. After 60 min both AQP1 and AQP4 increased in the stomach without any macroscopically detectable changes, then decreased depending on time. (3) The immunohistochemical investigations using our monoclonal antibodies seem to support our present quantitative results. CONCLUSION: chemically induced gastric mucosal lesions are started by an extended edema. In the induction of the edema and the subsequent gastric injury, aquaporins (both AQP1 and AQP4) play an important role in the maintenance of mucosal integrity.

Mechanisms of action of retinoids in gastrointestinal mucosal protection in animals, human healthy subjects and patients.

UNLABELLED: Retinoids prevent chemically induced gastric mucosal damage without inhibiting gastric acid secretion ("nutritional gastric cytoprotection"). The gastroprotective effects of retinoids do not depend on 1) vitamin A activity; 2) number of unsaturated double bonds; 3) the presence of a characteristic chemical structure of their terminal components; however, they depend on 1) intact vagal nerve and 2) adrenals in experimental animals. The gastric cytoprotective effect of retinoids produces a dose-dependent inhibition of ATP-transformation into ADP. It also increases the transformation of ATP into cAMP. Other features of these gastric cytoprotective effects of retinoids include: 1) The retinoid-induced gastric mucosal protection differs from that of PGs; 2) The cAMP is an intracellular signal in the development of gastric mucosal damage produced by chemicals (e.g., ethanol, HCl, indomethacin) and in the protection of gastric mucosa induced by retinoids (but not by PGs); 3) The gastric mucosal protection induced by retinoids and gastric mucosal permeability can be separated in time. The existence of gastric mucosal protection can be demonstrated in healthy persons (against indomethacin treatment), in patients with gastric ulcer (GU) and duodenal ulcer (DU) without any inhibition of gastric acid secretion. The serum levels of vitamin A and zeaxanthin were significantly decreased in patients with chronic gastrointestinal (GI) inflammatory diseases (e.g., terminal ileitis, ulcerative colitis), colorectal polyposis, and different (e.g., esophageal, gastric, pancreatic, hepatocellular and colorectal) malignant diseases. The serum levels of vitamin A provitamins were unchanged and their GI mucosal protective effects do not depend on vitamin A activity. CONCLUSIONS: 1) Abundant experimental and human observations clearly proved the defensive role of retinoids in the GI tract; 2) There is a correlation between the a) scavenger properties of retinoids vs. intact vagal nerve; b) scavenging properties vs. intact adrenals. 3) The GI mucosal protective effect of retinoids is correlated with biochemical changes in the GI mucosa.

Gastrin and pentagastrin enhance the tumour proliferation of human stable cultured gastric adenocarcinoma cells.

The effect of gastrin on stimulating tumour proliferation has been evaluated on human pancreas cancer cells in culture and in tumours transplanted to nude mice. The presence of CCK-B/gastrin-like receptor responsible for that effect of gastrin has been proved in colonic (WiDr, HT-29, YAMC) and pancreatic (PANC-1, BON) cell lines. The aim of our study was to examine the stimulating effect of gastrin and pentagastrin on the growth of human gastric adenocarcinoma cell line. The human gastric adenocarcinoma cell line (AGS, CRL-1739) was purchased from ATCC (Rockville, MA, USA). Gastrin-17 was purchased from Sigma-Aldrich (Budapest, Hungary), pentagastrin was from Zeneca Limited (Macclasfield, UK). The cells were incubated in DMEM containing 10% FCS on 96-well culturing plate with 10(4) cells/well starting cell number at 37 degrees C with 5% CO2. The proliferation rates were detected: by the measurements of the metabolically active cells with Owen's reagent and the determination of protein content, and by cell counting in a haemocytometer at several incubation times. As a result, we detected similar proliferation rates using gastrin-17 or pentagastrin in the incubation medium. The stimulating effect of gastrin/pentagastrin on cell line proliferation was in correlation with its concentration. Our results proved that pentagastrin is a 10 times less effective stimulator of proliferation of gastric cancer than gastrin-17, and that AGS human adenocarcinoma cell line might be CCK receptor positive.

Evidence for the involvement of oxygen free radicals in the ethanol-induced late cellular injury in mouse myeloma cells.

In this study, we analysed the ethanol-induced long term cell injury on a general cell model (Sp2/0-Ag14 cell line). Cells were incubated in 1, 5, 10, 15 and 20% of ethanol (EtOH) for 5 min. After washing cell viability was tested by the Trypan Blue exclusion test in 5, 60 min, 4 and 24 h after EtOH exposure. Free radicals were monitored every 30 min by electron spin resonance (ESR) with alpha-phenyl-N-tert-butylnitrone (PBN) spin trapping technique. Scavenger compounds such as glutathione (GSH), dimethyl sulfoxide (DMSO) and 5,5-dimethyl-1-pyrroline N-oxide (DMPO) were applied for 24 h incubation after EtOH exposure. EtOH concentration dependently decreased the cell viability immediately after 5 min exposure, but with 4 and 24 h, a secondary cell destruction was found. Using ESR-spin trapping technique, an increased free radical activity could be detected. DMPO, DMSO and GSH significantly, but in different period protected the cells against free-radical induced cellular damage. EtOH produces an early (immediately after EtOH exposure) and a late (in about 4 h) cellular damage on Sp2/0-Ag14 cells. The oxygen free radicals can be detected in a short time after EtOH exposure, its biological effect manifested as a secondary cell destruction at 4 and 24 h. This phenomenon can be prevented by scavenger compounds.

Difference between the effect of acute and chronic surgical vagotomy on the cytoprotective action of atropine against indomethacin-induced mucosal lesions on the gastrointestinal tract in rats.

The cytoprotective effect of a small dose of atropine was proved against the indomethacin (IND)-caused gastrointestinal (GI) mucosal damage. This protective effect of atropine disappeared in the acute phase of surgical vagotomy (ASV) on the vagally-innervated parts of GI tract. The aims of our observations were: 1) to examine the effect of chronic surgical vagotomy (CSV) on the cytoprotective action of atropine in the GI tract; and 2) to compare the effects of ASV and CSV on the GI cytoprotection caused by atropine against IND-induced mucosal damage and vascular permeability in rats. The IND was given s.c. 24 h prior to the killing of the animals in a dose of 20 mg x kg(-1). Bilateral surgical vagotomy or sham operation were carried out 24 h (ASV) or 14 d (CSV) before IND-application. Atropine was given i.p. every 5 h after IND-treatment in a dose of 0.1 mg x kg(-1). The number of macroscopical mucosal ulcerations was noted and its severity was calculated by semiquantitative scale in the stomach, small intestine and three equal parts of colon. Vascular permeability was measured by Evans-blue leakage into the mucosal tissue. It has been found that: 1) Tte small dose of atropine significantly decreased the IND-induced mucosal damage and vascular permeability on the stomach, small intestine and the vascular permeability on the proximal colon; 2) the small dose of atropine did not cause any changes in the appearance of IND-induced mucosal lesions and in Evans blue concentration in the mucosa after ASV, but it significantly decreased the IND-caused mucosal damage and Evans blue concentration in the mucosa of stomach, small intestine and proximal colon after CSV; 3) the IND-induced mucosal damage and vascular permeability treated with atropine (given in cytoprotective dose) were significantly smaller after CSV than that after ASV on the stomach, small intestine and proximal colon. It has been concluded that the intact vagal nerve has an essential role in the appearance of cytoprotective mechanisms of atropine in GI tract.

Effects of indomethacin, with vitamin A or beta-carotene, on the rat gastric mucosa: extra-and intracellular membrane-bound ATP mechanisms.

BACKGROUND: Indomethacin (IND) is a widely used non-steroidal anti-inflammatory agent in the treatment of various inflammatory disorders, which causes gastrointestinal injury in humans and animal experiments. Vitamin A and beta-carotene prevent the IND-induced gastric mucosal injury. These compounds modify the membrane-bound ATP-dependent energy systems. The aims of this investigation were: (1) To study the IND-induced gastric mucosal damage and its prevention by vitamin A and beta-carotene; (2) to measure the biochemical compounds of the gastric mucosa ATP, ADP, ATP/ADP, AMP, ATP+ADP+AMP, 'energy charge' (ATP + 0.5 ADP)/(ATP+ADP+AMP), cAMP, lactate under the circumstances mentioned above; (3) to analyze the extra- and intracellular regulatory mechanisms between the membrane-bound ATP-dependent energy systems. METHODS: The observations were carried out with CFY (Sprague-Dawstrein rats, weighing 180-210 g). The gastric mucosal damage was produced by IND (20 mg/kg sc. administration) and it was prevented by vitamin A (or beta-carotene), given in doses of 0.01-0.1 to 1.0-10.0 mg/kg ig. Different biochemical compounds (ATP, ADP, AMP, cAMP, lactate) and parameters (ATP/ADP, adenylate pool, 'energy charge') were measured and calculated. RESULTS: (1) Vitamin A and beta-carotene prevented dose-dependently the IND-induced gastric mucosal damage; (2) the extent of ATP-ADP transformation was increased significantly, while the ATP-cAMP decreased in the gastric mucosa after IND-treatment; (3) vitamin A and beta-carotene enhanced the extent of ATP-cAMP transformation, while the ATP-ADP transformation was inhibited (the actions were dose-dependent responses); (4) No change was found in 'energy charge' by IND, while its value decreased significantly with vitamin A and beta-carotene. CONCLUSIONS: (1) A very complex extra- and intracellular feedback mechanism system exists in the gastric mucosa during IND, IND + vitamin A, and IND + beta-carotene treatments; (2) The gastric mucosal preventive effect of vitamin A and beta-carotene only partly depend on their scavenger properties.

Cellular mechanisms of beta-carotene-induced gastric cytoprotection in indomethacin-treated rats.

Indomethacin (IND) is a non-steroidal anti-inflammatory agent which is widely used in the treatment of various inflammatory disorders. The drug causes gastrointestinal injury in humans and experimental animals. The aim of these studies was to examine the time course correlation between the macroscopic appearance of mucosal damage, tissue level of PGE(2) and adenosine nucleotide metabolism during the development of indomethacin (IND)-induced mucosal damage and its prevention by beta-carotene.The observations were carried out on both sexes of CFY-strain rats, weighing 180-200 g. Gastric mucosal damage was produced by subcutaneous administration of IND (20 mg/kg). beta-Carotene (Hoffman-La Roche, Switzerland) was given intragastrically at the time of IND administration at doses of 0.01, 0.1, 1 and 10 mg/kg. The animals were sacrificed at 0, 1, 2, 3 and 4 h after IND administration when the number and severity of mucosal lesions were noted and the tissue levels of ATP, ADP, AMP, cAMP, lactate and PGE(2) were measured from the total homogenate of gastric mucosa. The ratio of ADP/ATP, the values of the adenylate pool (ATP+ADP+AMP), and 'energy charge' [(ATP+0.5ADP)/(ATP+ADP+AMP)] were calculated.It was found that: (a) gastric mucosal lesions appear macroscopically 2 h after IND administration; (b) the tissue level of ATP decreased, while ADP was increased 1 h after administration; (c) the most significant decrease in cAMP was found 1 h after IND administration, and thereafter its level returned to baseline; (d) beta-carotene dose-dependently prevented the IND-induced mucosal damage and elevated the cAMP level, but it did not alter the mucosal PGE(2) level 3 or 4 h after IND administration; (e) beta-carotene produced an elevation in ATP and a decrease in ADP level; (f) no significant changes were found in 'energy charge' of the gastric mucosa in IND-treated animals.The development of gastric mucosal damage due to IND was associated with increased energy liberation, i.e. transformation of ATP into ADP, and decreased ATP-cAMP transformation. The significant decrease in cAMP preceded the macroscopic appearance of mucosal damage. The increase in ATP-cAMP transformation is involved in the development of beta-carotene-induced gastric cytoprotection.

Direct cellular effects of some mediators, hormones and growth factor-like agents on denervated (isolated) rat gastric mucosal cells.

The brain-gut axis has an important role in the mechanism of gastric cytoprotection in vivo. The aim of this study was to evaluate the in vitro effect of protective agents without any central and peripheral innervation. A mixed population of rat gastric mucosal cells was isolated by the method of Nagy et al (Gastroenterology (1994) 77, 433-443). Cells were incubated for 60 min with cytoprotective drugs such as prostacyclin, histamine, pentagastrin and PL-10 substances (synthesized parts of BPC). At the end of this incubation cells were treated by 15% ethanol for 5 min. Cell viability was tested by trypan blue exclusion test and succinic dehydrogenase activity. The following results were obtained: 1) prostacyclin, histamine and pentagastrin had no direct cytoprotective effect on isolated cells; and 2) PL-10 substances significantly protected the cells against ethanol-induced cellular damage. This led to the following conclusions: 1) in the phenomenon of gastric cytoprotection only the growth factor-like agents have a direct cellular effect; and 2) the intact peripheral innervation is basically necessary for the development of mediators and hormone-induced gastric cytoprotection.

Evidence for direct cellular protective effect of PL-10 substances (synthesized parts of body protection compound, BPC) and their specificity to gastric mucosal cells.

The direct gastric mucosal cellular effect of four PL-10 substances (a synthesized part of human body protection compound, BPC containing 14 or 15 amino acids) was studied on freshly isolated rat gastric mucosal cells and on a mouse myeloma cell line (Sp2/0-Ag14) in an ethanol-induced cell injury model. The examined substances were not toxic for the cells. Two of them proved to be significantly protective against the direct cellular damaging effect of ethanol (PL 10.1.15AK-3 in 5 microg/ml dose and PL 10.1.AK14-2 dose-dependently, ED50=50 ng/ml) on gastric mucosal cells. This cytoprotective effect was failured on mouse myeloma cells. Based on these results a part of the in vivo protection induced by BPC seems to be a direct cellular protective effect to gastric mucosal cells.

[Direct cytotoxic and cytoprotective effects of some drugs on isolated cells of gastric mucosa from rats]. / Direkt sejtkárosító és -védö hatások vizsgálata patkány izolált gyomornyálkahártya-sejtjein.

Toxic effect of ethanol and indomethacin, and the cytoprotective effect of prostacyclin were studied. In absence of other aggressive factors, the indomethacin was found to be non-toxic, but it could enhance the necrotizing effect of ethanol, this effect could be counteracted by prostacyclin preincubation. These observations suggest that there is an endogenous prostaglandin system in rat gastric mucosal cells that may protect against the toxic effect of indomethacin; administered prostacyclin may have a cytoprotective effect when this endogenous prostaglandin system's protective function does not more function. Gastric mucosal cytoprotection may include cellular level processes, which are able to operate without the existence of tissue integrity.

[Effect of homogenized human pathogenic Helicobacter pylori on the viability of isolated rat gastric mucosal cells]. / A humán patogén Helicobacter pylori homogenizátum hatása patkány izolált gyomornyálkahártya sejtjeinek életképességére.

Aim of this study was to detect the possible direct cellular effect of Helicobacter pylori (Hp) (obtained by biopsy from patients with gastric and duodenal ulcer) on freshly isolated rat gastric mucosal cells. Urease test positive Hp cultured from human biopsy sample was sonicated and incubated with freshly isolated rat gastric mucosal cells. The direct cellular damaging effect of Hp was evaluated alone and in combination with ethanol and indomethacin. The cellular damaging effect was tested morphologically (Trypan blue exclusion) and biochemically (measurements of lactate dehydrogenase, succinic dehydrogenase and ethidium bromide DNA fluorescence). Hp alone, or in combination with ethanol and indomethacin had no direct cellular toxicity on freshly isolated rat gastric mucosal cells. The isolated and cultured Hp collected from human beings did not produce any cellular damage on freshly isolated rat gastric mucosal cells.

Preventive effect of atropine on indomethacin-induced gastrointestinal mucosal and vascular damage in rats.

The protective effect of 'chemical vagotomy' (atropine given in three doses: 0.1, 0.5 and 1.0 mg/kg i.p.) was examined on indomethacin (IND, 20 mg/kg s.c.)-induced macroscopic gastrointestinal (GI) mucosal erosions and changes of vascular permeability in the stomach and three equal parts of small intestine and colon in rats. The different doses of atropine were administered at 0, 5, 10, 15 and 20 h after IND administration, then the number and severity of lesions were noted and the vascular damage was measured by Evans blue extravasation into the mucosa and intraluminal juice at 24 h after the IND treatment. Our results indicate that atropine ('chemical vagotomy') dose-dependently and significantly decreases the IND-induced mucosal erosions and vascular permeability in the vagal nerve-innervated parts of GI tract (i.e. the stomach, small intestine and proximal colon). Atropine in 0.5 and 1.0 mg/kg doses has a significantly higher protective effect on the vascular damage than on the macroscopic mucosal lesions in the stomach, small intestine and proximal colon. The vascular permeability is only one of those factors which have a role in the appearance of the GI mucosal erosions after IND treatment. These results suggest that the decrease of vascular permeability is involved in the protective effect of atropine against IND-induced GI mucosal damage.