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  1. 10 Journal of Physiology and Pharmacology. Supplement

  2. 9 Journal of Physiology and Pharmacology

  3. 2 BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

  4. 1 Acta Academiae Agriculturae ac Technicae Olstenensis. Agricultura

  5. 1 Acta Microbiologica Polonica

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  1. 12 Konturek S. J.

  2. 7 Pawlik W. W.

  3. 6 Brzozowski T.

  4. 6 Konturek P. C.

  5. 5 Jaworek J.

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  1. 1 2021

  2. 1 2019

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  4. 1 2014

  5. 2 2012

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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Production of indole acetic acid by Kocuria rosea VB1 and Arthrobacter luteolus VB2 under the influence of L-tryptophan and maize root exudates

100%
Karnwal A.
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
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2019
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tom 100
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nr 1
2
Content available remote

Melatonin and its precursors L-tryptophan prevent acute gastric mucosal damage induced by aspirin in humans

100%
Konturek P. C., Celinski K., Slomka M., Cichoz-Lach H., Burnat G., Naegel A., Bielanski W., Konturek J. W., Konturek S. J.
Journal of Physiology and Pharmacology. Supplement
|
2008
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tom 59
|
nr 2
Melatonin (MT) and its precursor L-tryptophan (Trp) are implicated in the protection of gastric mucosa against noxious agents. However, the role of MT and Trp on the gastric mucosal injury induced by aspirin (ASA) in human has not been investigated. Studies in animals showed that both MT and Trp given intragastrically prevents the formation of gastric mucosal lesions induced by ASA. The aim of the present study was to determine the influence of MT and Trp given orally to healthy humans on gastric mucosal lesions induced by ASA. The present study included 21 healthy, Hp-negative male volunteers with intact gastro-duodenal mucosa aging 20-50 yr. They were divided in 3 groups; group1: 7 volunteers receiving daily 2 x 1g ASA (Polfa, Rzeszow) during 11 days; group 2: 7 healthy volunteers receiving 2x1g ASA and MT (Lekam, Zakroczyn) (5 mg 30 min prior to ASA) during 11 days and group 3: 7 healthy volunteers receiving 2x1g ASA and Trp (Ardeytropin, Germany) (0.5 g 30 min prior to ASA) during 11 days. Mucosal damage was evaluated at 3rd, 7th and 11th days of ASA administration by endoscopy using Lanza score. Plasma melatonin was measured using RIA and gastric mucosal generation of PGE2 was assessed also by RIA. ASA caused marked mucosal injury at all days of its administration except day 11th when only moderate lesions were evident. Pre-treatment with MT or Trp alone was accompanied by a significant decrease in gastric mucosal lesion score. Gastric mucosal generation of PGE2 was suppressed by about 90% in subjects treated with ASA without or with MT or Trp. We concluded that: MT and its precursor Trp significantly attenuate gastric mucosal lesions induced by aspirin. The action of Trp may be be mediated by MT produced in gastrointestinal tract from Trp. The gastroprotective action of MT and Trp is independent on gastric mucosal PGE2 generation.
3
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Melatonin precursor, L-tryptophan protects the pancreas from development of acute pancreatitis through the central site of action

100%
Leja-Szpak A., Jaworek J., Tomaszewska R., Nawrot K., Bonior J., Kot M., Palonek M., Stachura J., Czupryna A., Konturek S. J., Pawlik W. W.
Journal of Physiology and Pharmacology
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2004
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tom 55
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nr 1,2
Melatonin, produced from L-tryptophan, protects the pancreas against acute damage by improving the antioxidative status of tissue. Melatonin receptors have been detected in the brain, but the contribution of these receptors to the pancreatic protection is unknown. The aim of our study was to compare the effects of melatonin precursor; L-tryptophan given intracerebroventricularly (i.c.v.) or intraperitoneally (i.p.) on the course of acute pancreatitis. Acute pancreatitis was induced by subcutaneous infusion of caerulein (5µg/kg-h x 5h). L-tryptophan was given i.p. (2.5, 25 or 250 mg/kg) or administered into right cerebral ventricle (0.02, 0.2 or 2.0 mg/rat) 30 min prior to the start of caerulein infusion. Plasma amylase, lipase and TNF alpha activities were measured to determine the severity of caerulein-induced pancreatitis (CIP). The lipid peroxidation products: malonylodialdehyde and 4-hydroksynonenal (MDA + 4-HNE) and activity of superoxide dismutase (SOD) were measured in the pancreas of intact or CIP rats with or without L-tryptophan pretreatment. Melatonin blood level was measured by RIA. CIP was confirmed by histological examination and manifested as an edema and rises of plasma levels of amylase, lipase and TNF alpha (by 550%, 1000% and 600%). MDA + 4-HNE was increased by 600%, whereas SOD activity was reduced by 75% in the pancreas of CIP rats. All manifestations of CIP were significantly reduced by pretreatment of the rats with L-tryptophan given i.c.v. at doses of 0.2 or 2.0 mg/rat, or by peripheral administration of this amino acid used at dose of 250 mg/kg i.p. In control rats plasma level of melatonin averaged about 40 ± 2 pg/ml and was not significantly affected by CIP, by central application of L-tryptophan (0.02, 0.2 or 2.0 mg/rat) or by peripheral administration of this melatonin precursor used at doses of 2.5 or 25 mg/kg i.p. Plasma melatonin level was markedly increased by pretreatment of the rats with L-tryptophan given i.p. at dose of 250 mg/kg. We conclude that central administration of melatonin precursor; L-tryptophan, as well as peripheral application of high dose of this melatonin precursor prevented the pancreatic damage produced by CIP. The favorable effect of peripherally administered L-tryptophan could be related to the rise of melatonin plasma level and to pancreatoprotective action of this indoleamine. The beneficial effect of centrally administered L-tryptophan could be mediated through activation of central receptors for locally produced melatonin.
4
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Relative profiling of L-tryptophan derivatives from selected edible mushrooms as psychoactive nutraceuticals to inhibit P-glycoprotein: a paradigm to contest blood-brain barrier

84%
Margret A. A., Mareeswari R., Kumar K. A., Jerley A. A.
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
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2021
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tom 102
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nr 1
5
Content available remote

Conversion L-tryptophan to melatonin in the gastrointestinal tract: the new high performance liquid chromatography method enabling simultaneous determination of six metabolites of L-tryptophan by native fluorescence and UV-Vis detection

84%
Zagajewski J., Drozdowicz D., Brzozowska I., Hubalewska-Mazgaj M., Stelmaszynska T., Laidler P. M., Brzozowski T.
Journal of Physiology and Pharmacology
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2012
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tom 63
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nr 6
6
Content available remote

Peripheral distribution of kynurenine metabolites and activity of kynurenine pathway enzymes in renal failure

84%
Pawlak D., Tankiewicz A., Matys T., Buczko W.
Journal of Physiology and Pharmacology
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2003
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tom 54
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nr 2
We investigated L-kynurenine distribution and metabolism in rats with experimental chronic renal failure of various severity, induced by unilateral nephrectomy and partial removal of contralateral kidney cortex. In animals with renal insufficiency the plasma concentration and the content of L-tryptophan in homogenates of kidney, liver, lung, intestine and spleen were significantly decreased. These changes were accompanied by increase activity of liver tryptophan 2,3-dioxygenase, the rate-limiting enzyme of kynurenine pathway in rats, while indoleamine 2,3-dioxygenase activity was unchanged. Conversely, the plasma concentration and tissue content of L-kynurenine, 3-hydroxykynurenine, and anthranilic, kynurenic, xanthurenic and quinolinic acids in the kidney, liver, lung, intestine, spleen and muscles were increased. The accumulation of L-kynurenine and the products of its degradation was proportional to the severity of renal failure and correlated with the concentration of renal insufficiency marker, creatinine. Kynurenine aminotransferase, kynureninase and 3-hydroxyanthranilate-3,4-dioxygenase activity was diminished or unchanged, while the activity of kynurenine 3-hydroxylase was significantly increased. We conclude that chronic renal failure is associated with the accumulation of L-kynurenine metabolites, which may be involved in the pathogenesis of certain uremic syndromes.
7

Effect of L-tryptophane and indole-3-acetic acid on yield of field bean and soil microbial activity

84%
Kucharski J., Wyszkowska J., Nowak G.
Natural Sciences
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2000
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tom 05
8

Indole-3-acetic acid production and effect on sprouting of yam [Dioscorea rotundata L.] minisetts by Bacillus subtilis isolated from culturable cowdung microflora

84%
Swain M. R., Naskar S. K., Ray R. C.
Polish Journal of Microbiology
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2007
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tom 56
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nr 2
Bacillus subtilis strains (CM1-CM5) isolated from culturable (cowdung microflora were investigated for indole-3-acetic acid (IAA) production in nutrient broth (NB). All the strains tested produced IAA in NB; albeit in very low concentrations (0.09-0.37 mg/l). The addition of L-tryptophan (0.1-1.0 g/l) into NB substantially enhanced IAA production (6.1-31.5 folds) indicating that L-tryp-tophan was the precursor for IAA biosynthesis by these bacterial strains. Maximum IAA production was observed after 8 days of incubation (in late stationary phase of bacterial growth). The variation in IAA production was attributed to the genetic make up of these strains as evaluated by RAPD analysis of these isolates and B. subtilis type strain MTCC 441. Application of B. subtilis suspension (8 x 10⁹ CFU/ml) on the surface of yam (Dioscorea rotundata L.) minisetts increased the number of sprouts, roots and shoots length, root and shoot fresh weights and root: shoot ratio over those minisetts not treated with bacterial suspension. Fresh cowdung slurry treatment on yam minisetts also produced similar results as obtained with B. subtilis application.
9
Content available remote

Tryptophan free diet delays healing of chronic gastric ulcers in rat

84%
Konturek P. C., Burnat G., Brzozowski T., Zopf Y., Konturek S. J.
Journal of Physiology and Pharmacology. Supplement
|
2008
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tom 59
|
nr 2
Melatonin (MT) is an ubiquitous molecule, representing one of the phylogenetically oldest signaling mechanisms. Our previous studies demonstrated that MT and its precursor L-tryptophan (L-Trp) show strong protective effect on gastric mucosa. The aim of the present study was: 1) to assess the effect of MT and L-Trp on healing of chronic gastric ulcer and accompanying changes in gastric mucosal blood flow (GBF); 2) to study the effect of MT and L-Trp on expression of iNOS. cNOS and HSP70 in ulcerated mucosa; 3) to compare the effect of L-Trp free and L-Trp rich diet on ulcer healing and gene expression of proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-), superoxide dismutase (SOD), cyclooxygenase-2 (COX-2) and NFkappaB-p65 protein expression in ulcer area and intact non-ulcerated. Chronic ulcers were induced in Wistar rats by Okabe’s modification of acetic acid method. Rats with chronic gastric ulcers were divided in following treatment groups: 1) vehicle (saline); 2) MT (20mg/kg-d i.p.) and 3) L-Trp (100 mg/kg i.p.). The expression of iNOS, cNOS and HSP70 protein was measured by Western blot. In separate experiments, the influence of commercially available (Bio-Serv, USA) L-Trp free diet (TFD) was compared to the L-Trp rich diet (TRD) on the course of ulcer healing was assessed. The ulcer area was measured by planimetry. The expression of TNF, COX-2 and SOD mRNA in ulcerated mucosa was analyzed by RT-PCR method. MT and its precursor L-Trp significantly accelerated ulcer healing. Healing ulcerated mucosa showed increased protein expression of iNOS and HSP70 as compared to intact gastric mucosa. TFD in contrast to normal diet significantly attenuated the ulcer healing, whereas the TRD exerted opposite effects and significantly accelerated ulcer healing. This last effect was accompanied by significant decrease of TNF- mRNA expression and expression of NFkB-p65 in gastric mucosa. We conclude that: 1) MT and its precursor L-Trp significantly accelerate healing of gastric ulcer; 2) L-Trp free diet significantly attenuates experimental ulcer healing and this is due to decreased synthesis of MT from L-Trp by EE cells in gastric mucosa and 3) MT shows strong anti-inflammatory effects due to inhibition of NFkappaB and TNF- expression.
10
Content available remote

Involvement of vagal nerves in the pancreatostimulatory effects of luminal melatonin, or its precursor L-tryptophan. Study in the rats

67%
Nawrot-Porabka K., Jaworek J., Leja-Szpak A., Szklarczyk J., Kot M., Mitis-Musiol M., Konturek S. J., Pawlik W. W.
Journal of Physiology and Pharmacology. Supplement
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2007
|
tom 58
|
nr 6
11
Content available remote

New insight into oesophageal injury and protection in physiologically relevant animal models

67%
Zayachkivska O., Pshyk-Titko I., Hrycevych N., Savytska M.
Journal of Physiology and Pharmacology
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2014
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tom 65
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nr 2
12
Content available remote

Melatonin as modulator of pancreatic enzyme secretion and pancreatoprotector

67%
Jaworek J., Nawrot-Porabka K., Leja-Szpak A., Bonior J., Szklarczyk J., Kot M., Konturek S. J., Pawlik W. W.
Journal of Physiology and Pharmacology. Supplement
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2007
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tom 58
|
nr 6
13
Content available remote

Mucosal strengthening activity of central and peripheral melatonin in the mechanism of gastric defense

67%
Brzozowska I., Ptak-Belowska A., Pawlik M., Bajdo R., Drozdowicz D., Konturek S. J., Pawlik W. W., Brzozowski T.
Journal of Physiology and Pharmacology. Supplement
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2009
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tom 60
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nr 7
14
Content available remote

The effects of L-tryptophan and melatonin on selected biochemical parameters in patients with steatohepatitis

67%
Cichoz-Lach H., Celinski K., Konturek P. C., Konturek S. J., Slomka M.
Journal of Physiology and Pharmacology
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2010
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tom 61
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nr 5
15
Content available remote

Exogenous melatonin abolishes mechanical allodynia but not thermal hyperalgesia in neuropathic pain. The role of the opioid system and benzodiazepine-GABAergic mechanism

67%
Zurowski D., Nowak L., Machowska A., Wordliczek J., Thor P. J.
Journal of Physiology and Pharmacology
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2012
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tom 63
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nr 6
16
Content available remote

Modulation of pancreatic enzyme secretion by melatonin and its precursor; L-tryptophan. Role of CCK and afferent nerves

67%
Leja-Szpak A., Jaworek J., Nawrot-Porabka K., Palonek M., Mitis-Musiol M., Dembinski A., Konturek S. J., Pawlik W. W.
Journal of Physiology and Pharmacology. Supplement
|
2004
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tom 55
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nr 2
33-46
Melatonin, a pineal hormone, is also produced in the gastrointestinal tract. Melatonin receptors have been detected in the stomach, intestine and pancreas. This indole inhibits insulin secretion but its role in the physiological modulation of exocrine pancreatic function is yet unknown. The aim of this study was to evaluate the pancreatic secretory effect of melatonin and its precursor; L-tryptophan given intraduodenally (i.d.) to the conscious rats with intact or capsaicin deactivated sensory nerves. CCK1 receptor antagonist; tarazepide, was used in the part of the study to determine the involvement of CCK in the secretory effects of melatonin. The secretory studies were performed on awaken rats surgically equipped with silicone catheters, one of them was inserted into pancreato-biliary duct, the other one - into duodenum. Melatonin (1, 5 or 25 mg/kg) or L-tryptophan (10, 50 or 250 mg/kg) were administered i.d. Samples of pancreatic juice were collected in 15 minutes aliquots. Tarazepide (2,5 mg/kg i.p.) was given to the rats 15 min prior to the administration of melatonin or L-tryptophan. Neurotoxic dose of capsaicin (100 mg/kg s.c.) was used to deactivate afferent nerves and thus to assess the role of these nerves in the melatonin-induced pancreatic enzyme secretion. Administration of melatonin (1, 5 or 25 mg/kg i.d.) or L-tryptophan (10, 50 or 250 mg/kg i.d.) significantly increased pancreatic amylase outputs. Deactivation of sensory nerves by capsaicin or administration of CCK1 - receptor antagonist; tarazepide, reversed the stimulatory effects of melatonin or L-tryptophan on pancreatic secretory function. Administration of melatonin or its amino-acid precursor to the rats resulted in the significant and dose-dependent rises of melatonin and CCK plasma levels. We conclude that melatonin or its precursor; L-tryptophan stimulates pancreatic enzyme secretion via stimulation of CCK release and activation of duodeno-pancreatic reflexes.
17
Content available remote

Overview of the role of vitamins and minerals on the kynurenine pathway in health and disease

67%
Majewski M., Kozlowska A., Thoene M., Lepiarczyk E., Grzegorzewski W. J.
Journal of Physiology and Pharmacology
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2016
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tom 67
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nr 1
18
Content available remote

Role of melatonin in upper gastrointestinal tract

67%
Konturek S. J., Konturek P. C., Brzozowski T., Bubenik G. A.
Journal of Physiology and Pharmacology. Supplement
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2007
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tom 58
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nr 6
19
Content available remote

Does melatonin play a role in aging processes?

67%
Karasek M.
Journal of Physiology and Pharmacology. Supplement
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2007
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tom 58
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nr 6
20
Content available remote

Influence of melatonin and its precursor L-tryptophan on the dependent contact hypersensivity

67%
Majewska M., Zajac K., Zemelka M., Szczepanik M.
Journal of Physiology and Pharmacology. Supplement
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2007
|
tom 58
|
nr 6
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