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1.
Heliyon ; 9(4): e15242, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37151693

RESUMO

Background: Deep tissue massage (DTM), based on deep palpation and elimination of fascia restrictions, can reduce symptoms resulting from fascial disorders. The goal of this study was the analysis of the DTM effect on respiratory parameters in healthy people. Material and methods: The study involved a group of 40 people divided into two subgroups. The experimental group underwent a single DTM session. Classic massage was performed in the control group. Before and after treatment the chest circumference and oxygen saturation were measured and a spirometry test was performed. Results: The chest expandability significantly increased in both groups with greater effect in DTM group. Vital capacity and saturation, significantly increased in the experimental group. No significant changes in dynamic parameters were noticed in the control group, while FVC slightly decreased in the experimental group. Conclusions: In this study, deep tissue massage appeared to improve chest expendability and vital capacity with simultaneous decrease of FVC in healthy subjects. Further studies are needed to specify the effect of DTM on the respiratory system.

3.
Anticancer Agents Med Chem ; 19(17): 2079-2090, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30987575

RESUMO

BACKGROUND: L-kynurenine, derivate of L-tryptophan, is synthetized by indoleamine 2,3-dioxygenase (IDO). The effects of L-kynurenine depend on its binding to an aryl hydrocarbon receptor (AhR). OBJECTIVE: The aim of this study was to investigate the changes within the apoptotic pathway in PANC-1 cells subjected to L-kynurenine or L-tryptophan considering the production of anti-apoptotic proteins from the IAPs and Bcl-2 family, as well as the regulation of NF-κB signaling. METHODS: The investigated substances were added alone or in combination with the AhR inhibitor (CH223191) to cultures of PANC-1 cells. Cytoplasmic and nuclear proteins were analyzed by immunoblotting and cells were incubated with the investigated substances to determine cytotoxicity and proliferative effects. RESULTS: Incubation of PANC-1 cells with L-kynurenine or L-tryptophan resulted in the increase in antiapoptotic cIAP-1, cIAP-2, XIAP and Bcl-2 expression and a decrease in pro-apoptotic Bax. These changes were accompanied by the reduction of active caspases -9, -3 and PARP-1. The treatment leads to translocation and enhanced production of nuclear NF-κB p50 and Bcl-3. Incubation of the cells with AhR blocker either alone or together with L-kynurenine or L-tryptophan resulted in the opposite effect, leading to the downregulation of IAPs and Bcl-2, upregulation of Bax and caspases expression. CONCLUSION: 1) L-kynurenine and its precursor promote anti-apoptotic effects through the modulation of IDOdependent pathway and regulation of IAPs, Bcl-2 and NF-κB family members in pancreatic carcinoma cells 2) inhibition of AhR by CH223191 exerts an apoptosis-promoting effect, and this observation might suggest the potential use of this compound in pancreatic cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Compostos Azo/farmacologia , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Cinurenina/farmacologia , NF-kappa B/antagonistas & inibidores , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Pirazóis/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Compostos Azo/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Cinurenina/química , Estrutura Molecular , NF-kappa B/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Pirazóis/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Neoplasias Pancreáticas
4.
Pancreatology ; 19(3): 401-408, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30833212

RESUMO

OBJECTIVE: Chemerin, an adipokine, works as the chemoattractant for the immune cells. The role of chemerin in the inflammatory reaction is controversial. Chemerin has been shown to aggravate the inflammatory response, but other studies demonstrated its anti-inflammatory influence. This study assessed the effects of chemerin on acute pancreatitis (AP) in vivo and in vitro. METHODS: For in vivo experiments male Wistar rats were used. For in vitro study rat pancreatic AR42J cells were employed. Chemerin (1, 5 or 10 µg/kg) was given to the rats prior to the induction of AP by subcutaneous caerulein infusion (25 µg/kg). For in vitro studies cells were subjected to caerulein (10 nM) with or without chemerin (100 nM). Serum amylase activity was measured by enzymatic method, serum TNFα concentration - by ELISA kit. Western-blot was used to examine cellular proteins. RESULTS: AP was confirmed by histological examination. Chemerin given to AP rats decreased histological manifestations of AP, reduced serum amylase activity and TNFα concentration. In AR42J cells subjected to caerulein with addition of chemerin signal for TNFα was reduced comparing to the cultures treated with caerulein alone. Analysis of the dynamics of nuclear translocation for p50, p65 and Bcl-3 points out to NF-κB attenuation as a mechanism of observed anti-inflammatory action of chemerin. CONCLUSION: Chemerin significantly alleviated severity of AP in the rat, this is possibly due to the inhibition of pro-inflammatory signaling in the pancreatic cells.


Assuntos
Quimiocinas/uso terapêutico , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , NF-kappa B/metabolismo , Pancreatite/induzido quimicamente , Animais , Linhagem Celular , Ceruletídeo/toxicidade , Quimiocinas/administração & dosagem , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Masculino , Pâncreas/citologia , Pancreatite/tratamento farmacológico , Ratos , Ratos Wistar
5.
Pharmacol Rep ; 70(6): 1079-1088, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30308458

RESUMO

BACKGROUND: Gemcitabine is a standard chemotherapeutic agent for patients suffering from pancreatic cancer. However, the applied therapy is not effective due to the resistance of tumor cells to cytostatics, caused by inefficiency of the apoptotic mechanisms. Herein, we present the hypothesis that melatonin and its metabolite N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK) modify the effect of gemcitabine on PANC-1 cells and that this phenomenon is dependent on the modulation of apoptosis. METHODS: PANC-1 cells have been incubated with melatonin, AFMK or gemcitabine alone or in combination to determine the cytotoxity and proliferative effects. In subsequent part of the study, cells were harvested, the proteins were isolated and analyzed employing immunoprecipitation/immunoblotting. RESULTS: Incubation of PANC-1 cells with gemcitabine resulted in upregulation of pro-apoptotic bax and caspases proteins expression, downregulation of anti-apoptotic Bcl-2, heat shock proteins (HSPs) and modulation of cellular inhibitors of apoptosis (IAPs). Both melatonin and AFMK administered to PANC-1 in combination with gemcitabine inhibited the production of HSP70 and cIAP-2 as compared to the results obtained with gemcitabine alone. These changes were accompanied by upregulation of Bax/Bcl-2 ratio and reduction of procaspases-9 and -3 abundance, followed by an increase in the formation of active caspase of PANC-1 cells with combination of gemcitabine plus low doses of melatonin or AFMK led to enhanced cytotoxicity and resulted in the inhibition of PANC-1 cells growth as compared to effects of gemcitabine alone. CONCLUSION: Melatonin and AFMK could improve the anti-tumor effect of gemcitabine in PANC-1 cells presumably through the modulation of apoptotic pathway.


Assuntos
Antimetabólitos Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Cinuramina/análogos & derivados , Melatonina/metabolismo , Neoplasias Pancreáticas/metabolismo , Antimetabólitos Antineoplásicos/administração & dosagem , Apoptose/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Desoxicitidina/administração & dosagem , Desoxicitidina/metabolismo , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Cinuramina/administração & dosagem , Cinuramina/metabolismo , Melatonina/administração & dosagem , Gencitabina
6.
Gastroenterol Res Pract ; 2018: 6915059, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29576768

RESUMO

Background. Endotoxin (LPS), the component of Gram-negative bacteria, is responsible for sepsis and neonatal mortality, but low concentrations of LPS produced tissue protection in experimental studies. The effects of LPS applied to the suckling rats on the pancreas of adult animals have not been previously explored. We present the impact of neonatal endotoxemia on the pancreatic exocrine function and on the acute pancreatitis which has been investigated in the adult animals. Endotoxemia was induced in suckling rats by intraperitoneal application of LPS from Escherichia coli or Salmonella typhi. In the adult rats, pretreated in the early period of life with LPS, histological manifestations of acute pancreatitis have been reduced. Pancreatic weight and plasma lipase activity were decreased, and SOD concentration was reversed and accompanied by a significant reduction of lipid peroxidation products (MDA + 4 HNE) in the pancreatic tissue. In the pancreatic acini, the significant increases in protein signals for toll-like receptor 4 and for heat shock protein 60 were found. Signal for the CCK1 receptor was reduced and pancreatic secretory responses to caerulein were diminished, whereas basal enzyme secretion was unaffected. These pioneer studies have shown that exposition of suckling rats to endotoxin has an impact on the pancreas in the adult organism.

7.
Int J Mol Sci ; 18(7)2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28665321

RESUMO

Ghrelin was shown to exhibit protective and therapeutic effect in the gut. Aim of the study was to investigate the role of sensory nerves (SN) in the protective effect of ghrelin in acute pancreatitis (AP). Studies were performed on male Wistar rats or isolated pancreatic acinar cells. After capsaicin deactivation of sensory nerves (CDSN) or treatment with saline, rats were pretreated intraperitoneally with ghrelin or saline. In those rats, AP was induced by cerulein or pancreases were used for isolation of pancreatic acinar cells. Pancreatic acinar cells were incubated in cerulein-free or cerulein containing solution. In rats with intact SN, pretreatment with ghrelin led to a reversal of the cerulein-induced increase in pancreatic weight, plasma activity of lipase and plasma concentration of tumor necrosis factor-α (TNF-α). These effects were associated with an increase in plasma interleukin-4 concentration and reduction in histological signs of pancreatic damage. CDSN tended to increase the severity of AP and abolished the protective effect of ghrelin. Exposure of pancreatic acinar cells to cerulein led to increase in cellular expression of mRNA for TNF-α and cellular synthesis of this cytokine. Pretreatment with ghrelin reduced this alteration, but this effect was only observed in acinar cells obtained from rats with intact SN. Moreover, CDSN inhibited the cerulein- and ghrelin-induced increase in gene expression and synthesis of heat shock protein 70 (HSP70) in those cells. Ghrelin exhibits the protective effect in cerulein-induced AP on the organ and pancreatic acinar cell level. Sensory nerves ablation abolishes this effect.


Assuntos
Capsaicina/farmacologia , Ceruletídeo/toxicidade , Grelina/uso terapêutico , Pancreatite/induzido quimicamente , Pancreatite/tratamento farmacológico , Células Receptoras Sensoriais/efeitos dos fármacos , Células Receptoras Sensoriais/metabolismo , Animais , Citocinas/metabolismo , Grelina/farmacologia , Proteínas de Choque Térmico HSP70/metabolismo , Interleucina-4/metabolismo , Masculino , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
8.
Int J Mol Sci ; 18(5)2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28468316

RESUMO

Ghrelin (GHRL) is an endogenous ligand for the growth hormone secretagogue receptor (GHS-R). Experimental studies showed that GHRL protects the stomach and pancreas against acute damage, but the effect of GHRL on pancreatic acinar cells was still undetermined. AIM: To investigate the effect of GHRL and caerulein on the functional ghrelin system in pancreatic acinar cells taking into account the role of sensory nerves (SN). METHODS: Experiments were carried out on isolated pancreatic acinar cells and AR42J cells. Before acinar cells isolation, GHRL was administered intraperitoneally at a dose of 50 µg/kg to rats with intact SN or with capsaicin deactivation of SN (CDSN). After isolation, pancreatic acinar cells were incubated in caerulein-free or caerulein containing solution. AR42J cells were incubated under basal conditions and stimulated with caerulein, GHRL or a combination of the above. RESULTS: Incubation of isolated acinar cells with caerulein inhibited GHS-R and GHRL expression at the level of mRNA and protein in those cells. Either in rats with intact SN or with CDSN, administration of GHRL before isolation of acinar cells increased expression of GHRL and GHS-R in those cells and reversed the caerulein-induced reduction in expression of those parameters. Similar upregulation of GHS-R and GHRL was observed after administration of GHRL in AR42J cells. CONCLUSIONS: GHRL stimulates its own expression and expression of its receptor in isolated pancreatic acinar cells and AR42J cells on the positive feedback pathway. This mechanism seems to participate in the pancreatoprotective effect of GHRL in the course of acute pancreatitis.


Assuntos
Células Acinares/metabolismo , Ceruletídeo/farmacologia , Grelina/metabolismo , Receptores de Grelina/metabolismo , Células Receptoras Sensoriais/fisiologia , Células Acinares/efeitos dos fármacos , Animais , Linhagem Celular , Células Cultivadas , Retroalimentação Fisiológica , Grelina/genética , Masculino , Pâncreas/citologia , Pâncreas/inervação , Ratos , Ratos Wistar , Receptores de Grelina/genética , Regulação para Cima
9.
Int J Mol Sci ; 18(5)2017 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-28481310

RESUMO

Melatonin is an indoleamine produced from the amino acid l-tryptophan, whereas metabolites of melatonin are known as kynuramines. One of the best-known kynuramines is N¹-acetyl-N¹-formyl-5-methoxykynuramine (AFMK). Melatonin has attracted scientific attention as a potent antioxidant and protector of tissue against oxidative stress. l-Tryptophan and kynuramines share common beneficial features with melatonin. Melatonin was originally discovered as a pineal product, has been detected in the gastrointestinal tract, and its receptors have been identified in the pancreas. The role of melatonin in the pancreatic gland is not explained, however several arguments support the opinion that melatonin is probably implicated in the physiology and pathophysiology of the pancreas. (1) Melatonin stimulates pancreatic enzyme secretion through the activation of entero-pancreatic reflex and cholecystokinin (CCK) release. l-Tryptophan and AFMK are less effective than melatonin in the stimulation of pancreatic exocrine function; (2) Melatonin is a successful pancreatic protector, which prevents the pancreas from developing of acute pancreatitis and reduces pancreatic damage. This effect is related to its direct and indirect antioxidant action, to the strengthening of immune defense, and to the modulation of apoptosis. Like melatonin, its precursor and AFMK are able to mimic its protective effect, and it is commonly accepted that all these substances create an antioxidant cascade to intensify the pancreatic protection and acinar cells viability; (3) In pancreatic cancer cells, melatonin and AFMK activated a signal transduction pathway for apoptosis and stimulated heat shock proteins. The role of melatonin and AFMK in pancreatic tumorigenesis remains to be elucidated.


Assuntos
Melatonina/metabolismo , Neoplasias Pancreáticas/metabolismo , Pancreatite/metabolismo , Animais , Carcinogênese/metabolismo , Humanos , Melatonina/análogos & derivados , Pâncreas/enzimologia , Pâncreas/metabolismo , Receptores de Melatonina/metabolismo
10.
Exp Physiol ; 100(3): 267-77, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25641073

RESUMO

NEW FINDINGS: What is the central question of this study? Antisecretory factor, an endogenous protein detected in many tissues of the body, is known as an inhibitor of intestinal secretion, but its role in pancreatic exocrine secretory function has not yet been investigated. What is the main finding and its importance? In a rodent model, we show that antisecretory factor reduces pancreatic exocrine secretion, probably via its direct action on the pancreatic acini and via modulation of the enteropancreatic reflexes involving cholecystokinin and sensory nerves. Antisecretory factor (AF) regulates ion and water transport through the intestinal cell membrane. Antisecretory factor inhibits intestinal secretion, but its effect on the exocrine pancreas has not yet been shown. We investigated the effect of AF on pancreatic amylase secretion in vivo and in vitro using pancreatic acini isolated by collagenase digestion. For the in vivo study, Wistar rats were surgically equipped with silicone catheters, inserted into the pancreaticobiliary duct and into the duodenum. Capsaicin was used to deactivate the sensory nerves in turn to assess their involvement in the effects of AF on the exocrine pancreas. Antisecretory factor (1, 3 or 10 µg kg(-1) i.p.) was given in basal conditions or following stimulation of pancreatic secretion with diversion of pancreaticobiliary juice. For the in vitro study, rat pancreatic acini were incubated in the presence of increasing doses of AF (from 10(-8) to 10(-5)  m) alone or in combination with caerulein (10(-12)  m). Cytoplasmic cholecystokinin 1 (CCK1 ) receptor protein was detected by Western blot and immunoprecipitation studies. Antisecretory factor markedly reduced the output of pancreatic amylase both in basal conditions and when stimulated by diversion of pancreaticobiliary juice. Deactivation of the sensory nerves with capsaicin completely reversed the inhibitory effects of AF on the exocrine pancreas. Caerulein-induced enzyme secretion from the pancreatic acini was inhibited by AF, whereas basal secretion was unaffected. Administration of AF to the rats significantly diminished the synthesis of CCK1 receptor protein. We conclude that AF inhibits pancreatic exocrine secretion indirectly via sensory nerves and directly decreases amylase release from isolated pancreatic acini. The direct inhibitory action of AF on the exocrine pancreas could be related, at least in part, to a reduction of CCK1 receptors on pancreatic acinar cells.


Assuntos
Neuropeptídeos/metabolismo , Pâncreas Exócrino/metabolismo , Células Acinares/efeitos dos fármacos , Células Acinares/metabolismo , Amilases/metabolismo , Animais , Capsaicina/farmacologia , Ceruletídeo/metabolismo , Colecistocinina/metabolismo , Duodeno/efeitos dos fármacos , Duodeno/metabolismo , Técnicas In Vitro , Masculino , Pâncreas Exócrino/efeitos dos fármacos , Suco Pancreático/metabolismo , Ratos , Ratos Wistar , Células Receptoras Sensoriais/efeitos dos fármacos , Células Receptoras Sensoriais/metabolismo
11.
Pharmacol Rep ; 65(2): 494-504, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23744434

RESUMO

BACKGROUND: Serotonin (5-HT) is released from enterochromaffin cells in the gastrointestinal tract. 5-HT, via the activation of 5-HT2 and 5-HT3 receptors on vagal fibers, mediates pancreatic secretion through the mechanism independent from cholecystokinin. Melatonin (5-HT derivative) or L-tryptophan (melatonin or 5-HT precursor) given systemically or intraduodenally to the rats stimulate amylase secretion, but the mechanism is not clear. The aim of this study was to investigate the involvement of 5-HT in the pancreatostimulatory effect of melatonin or L-tryptophan, administered intraduodenally. METHODS: Wistar rats were surgically equipped with silicone catheters; inserted into pancreato-biliary duct and into the duodenum. Melatonin, L-tryptophan or 5-HT were given to the rats as a bolus. Combination of 5-HT2 or 5-HT3 receptor antagonists: ketanserin (100 µg/kg) and MDL72222 (250 µg/kg) was given intraperitoneally to the animals, 15 min. prior to the administration of the examined substances. The role of the vagal nerve, sensory fibers and CCK in the control of pancreatic exocrine function were determined. Blood samples were taken for the determination of 5-HT. RESULTS: Melatonin, 5-HT or L-tryptophan increased pancreatic amylase secretion. The stimulatory effect of the above substances was decreased by pretreatment of the rats with ketanserin and MDL72222. Bilateral vagotomy completely abolished the increase of amylase output caused by 5-HT, while capsaicin deactivation of sensory nerves or blockade of CCK1 receptor only partially reversed the stimulatory effect of 5-HT on the pancreas. Intraduodenal L-tryptophan, but not melatonin, increased plasma 5-HT concentrations in a dose- and time-dependent manner. CONCLUSION: Stimulation of pancreatic exocrine function caused by intraluminal administration of melatonin, or L-tryptophan is modified, at least in part, by serotoninergic mechanisms and vagal nerves.


Assuntos
Amilases/metabolismo , Melatonina/farmacologia , Serotonina/metabolismo , Triptofano/farmacologia , Animais , Relação Dose-Resposta a Droga , Duodeno/metabolismo , Ketanserina/farmacologia , Melatonina/administração & dosagem , Pâncreas/efeitos dos fármacos , Pâncreas/enzimologia , Ratos , Ratos Wistar , Receptor de Colecistocinina A/metabolismo , Antagonistas da Serotonina/farmacologia , Fatores de Tempo , Tropanos/farmacologia , Triptofano/administração & dosagem , Nervo Vago/metabolismo
12.
Int J Inflam ; 2012: 173675, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22606640

RESUMO

Melatonin, a product of the pineal gland, is released from the gut mucosa in response to food ingestion. Specific receptors for melatonin have been detected in many gastrointestinal tissues including the pancreas. Melatonin as well as its precursor, L-tryptophan, attenuates the severity of acute pancreatitis and protects the pancreatic tissue from the damage caused by acute inflammation. The beneficial effect of melatonin on acute pancreatitis, which has been reported in many experimental studies and supported by clinical observations, is related to: (1) enhancement of antioxidant defense of the pancreatic tissue, through direct scavenging of toxic radical oxygen (ROS) and nitrogen (RNS) species, (2) preservation of the activity of antioxidant enzymes; such as superoxide dismutase (SOD), catalase (CAT), or glutathione peroxidase (GPx), (3) the decline of pro-inflammatory cytokine tumor necrosis α (TNFα) production, accompanied by stimulation of an anti-inflammatory IL-10, (4) improvement of pancreatic blood flow and decrease of neutrophil infiltration, (5) reduction of apoptosis and necrosis in the inflamed pancreatic tissue, (6) increased production of chaperon protein (HSP60), and (7) promotion of regenerative process in the pancreas. Conclusion. Endogenous melatonin produced from L-tryptophan could be one of the native mechanisms protecting the pancreas from acute damage and accelerating regeneration of this gland. The beneficial effects of melatonin shown in experimental studies suggest that melatonin ought to be employed in the clinical trials as a supportive therapy in acute pancreatitis and could be used in people at high risk for acute pancreatitis to prevent the development of pancreatic inflammation.

13.
Pharmacol Rep ; 62(5): 864-73, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21098869

RESUMO

Melatonin, a pineal indoleamine, protects the pancreas against acute damage; however, the involvement of the pineal gland in the pancreatoprotective action of melatonin is unknown. The primary aim of this study was to determine the effects of pinealectomy on the course of acute caerulein-induced pancreatitis (AP) in rats. AP was induced by a subcutaneous infusion of caerulein (25 µg/kg) into pinealectomized or sham-operated animals. Melatonin (5 or 25 mg/kg) was given via intraperitoneal (ip) injection 30 min prior to the induction of AP. The pancreatic content of the lipid peroxidation products malondialdehyde and 4-hydroxynonenal (MDA + 4HNE) and the activity of an antioxidative enzyme, glutathione peroxidase (GSH-Px), were measured in each group of rats. Melatonin blood levels were measured by radioimmunoassay (RIA). In the sham-operated rats, AP was confirmed with histological examination and manifested as pancreatic edema and an increase in the blood lipase level (by 1,500%). In addition, the pancreatic content of MDA+ 4HNE was increased by 200%, and pancreatic glutathione peroxydase (GSH-Px) activity was reduced by 40%. Pinealectomy significantly aggravated the histological manifestations of AP, reduced the GSH-Px activity and markedly augmented the levels of MDA+ 4HNE in the pancreas of rats with or without AP as compared to sham-operated animals. Melatonin was undetectable in the blood of the pinealectomized rats with or without AP. Treatment with melatonin (25 mg/kg, ip) prevented the development of AP in the sham-operated rats and significantly reduced pancreatic inflammation in the animals previously subjected to pinealectomy. In conclusion, pineal melatonin contributes to the pancreatic protection through the activation of the antioxidative defense mechanism in pancreatic tissue as well as its direct antioxidant effects.


Assuntos
Pâncreas/efeitos dos fármacos , Pancreatite/fisiopatologia , Glândula Pineal/fisiopatologia , Doença Aguda , Aldeídos/metabolismo , Animais , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Ceruletídeo , Modelos Animais de Doenças , Glutationa Peroxidase/metabolismo , Infusões Subcutâneas , Injeções Intraperitoneais , Peroxidação de Lipídeos , Masculino , Malondialdeído/metabolismo , Melatonina/administração & dosagem , Melatonina/farmacologia , Pâncreas/metabolismo , Pâncreas/patologia , Pancreatite/induzido quimicamente , Pancreatite/patologia , Ratos , Ratos Wistar
14.
Growth Horm IGF Res ; 19(6): 517-22, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19615927

RESUMO

UNLABELLED: Growth hormone (GH) has been shown to protect the intestinal barrier integrity and to stimulate the production of insulin-like growth factor 1 (IGF-1), which inhibits the development of acute pancreatitis. Sensory nerves are implicated in the protection of pancreatic tissue against acute inflammation. The aim of this study was to investigate the influence of exogenous GH on acute pancreatitis (AP) and to assess the involvement of sensory nerves and IGF-1 in above effect. Studies were performed on Wistar rats. AP was induced by subcutaneous administration of caerulein (25mug/kg) to the conscious animals. GH (1 or 2mg/kg) was administered to the rats as an intraperitoneal injection 30min prior to the start of AP. To deactivate sensory nerves capsaicin was given at total dose of 100mg/kg 10days before the experiments. AP was confirmed by histological examination and manifested by the significant rises of pancreatic weight, and serum activities of lipase, TNFalpha and IL-10 (by 550%, 300% and 50%, respectively), whereas IGF-1 blood concentration was markedly reduced. Administration of GH prior to the caerulein infusion significantly increased GH, IGF-1 and IL-10 blood levels, attenuated harmful effects of AP and reduced histological manifestations of pancreatitis in the rats with intact sensory nerves. This was accompanied by the reduction of serum lipase, and TNFalpha activities. In the AP rats with capsaicin-deactivated sensory nerves GH failed to protect the pancreas against acute damage and, as a consequence of above deactivation, IGF-1 was low. CONCLUSION: GH modulates the development of acute pancreatitis in the presence of active sensory nerves probably via stimulation of IGF-1 release.


Assuntos
Hormônio do Crescimento/metabolismo , Pancreatite/metabolismo , Pancreatite/patologia , Células Receptoras Sensoriais/metabolismo , Doença Aguda , Animais , Capsaicina/farmacologia , Hormônio do Crescimento/sangue , Fator de Crescimento Insulin-Like I/biossíntese , Interleucina-10/sangue , Masculino , Modelos Biológicos , Pâncreas/inervação , Ratos , Ratos Wistar , Fármacos do Sistema Sensorial/farmacologia , Fator de Necrose Tumoral alfa/sangue
15.
Regul Pept ; 143(1-3): 56-63, 2007 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-17462749

RESUMO

Ghrelin, a 28-amino-acid peptide produced predominantly by oxyntic mucosa has been reported to affect the pancreatic exocrine function but the mechanism of its secretory action is not clear. The effects of intraduodenal (i.d.) infusion of ghrelin on pancreatic amylase outputs under basal conditions and following the stimulation of pancreatic secretion with diversion of pancreato-biliary juice (DPBJ) as well as the role of vagal nerve, sensory fibers and CCK in this process were determined. Ghrelin given into the duodenum of healthy rats at doses of 1.0 or 10.0 microg/kg increased pancreatic amylase outputs under basal conditions or following the stimulation of pancreatic secretion with DPBJ. Bilateral vagotomy as well as capsaicin deactivation of sensory fibers completely abolished all stimulatory effects of luminal ghrelin on pancreatic exocrine function. Pretreatment with lorglumide, a CCK(1) receptor blocker, reversed the stimulation of amylase release produced by intraduodenal application of ghrelin. Intraduodenal ghrelin at doses of 1.0 or 10.0 microg/kg increased plasma concentrations of CCK and ghrelin. In conclusion, ghrelin given into the duodenum stimulates pancreatic enzyme secretion. Activation of vagal reflexes and CCK release as well as central mechanisms could be implicated in the stimulatory effect of luminal ghrelin on the pancreatic exocrine functions.


Assuntos
Amilases/metabolismo , Pâncreas/efeitos dos fármacos , Hormônios Peptídicos/farmacologia , Animais , Capsaicina/administração & dosagem , Capsaicina/farmacologia , Colecistocinina/sangue , Duodeno/efeitos dos fármacos , Duodeno/metabolismo , Grelina , Humanos , Masculino , Pâncreas/enzimologia , Pâncreas/metabolismo , Hormônios Peptídicos/administração & dosagem , Proglumida/administração & dosagem , Proglumida/análogos & derivados , Proglumida/farmacologia , Radioimunoensaio , Ratos , Ratos Wistar , Receptor de Colecistocinina A/antagonistas & inibidores , Vagotomia
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