Immunohistochemical study on gastrointestinal endocrine cells of four reptiles

AIM： To darify the types, regional distributions and distribution densities as well as morphological features of gastrointestinal （GI） endocrine cells in various parts of the gastrointestinal track （GIT） of four reptiles, Gekko japonicus, Eumeces chinensis, Sphenomorphus indicus and Eumeces elegans. METHODS： Paraffin-embedded sections （5μm） of seven parts （cardia, fundus, pylorus, duodenum, jejunum, ileum, rectum） of GIT dissected from the four reptiles were prepared. GI endocrine cells were revealed by using immunohistochemical techniques of streptavidin-peroxidase （S-P） method. Seven types of antisera against 5-hydroxytryptamine （5-HT）, somatostatin （SS）, gastrin （GAS）, glucagon （GLU）, substance P （SP）, insulin and pancreatic polypeptide were identified and then GI endocrine cells were photomicrographed and counted. RESULTS： The GI endocrine system of four reptiles was a complex structure containing many endocrine cell types similar in morphology to those found in higher vertebrates. Five types of GI endocrine cells, namely 5-HT, SS, GAS, SP and GLU immunoreactive （IR） cells were identified in the GIT of G. faponicus, E. chinensis and S. indicus, while in the GIT of E. elegans only the former three types of endocrine cells were observed. No PP- and INS- IR cells were found in all four reptiles. 5-HT-IR cells, which were most commonly found in the pylorus or duodenum, distributed throughout the whole GIT of four reptiles. However, their distribution patterns varied from each other. SS-IR ceils, which were mainly found in the stomach especially in the pylorus and/or fundus, were demonstrated in the whole GIT of E. chinensis, only showed restricted distribution inthe other three species. GAS-IR cells, with a much restricted distribution, were mainly demonstrated in the pylorus and/or the proximal small intestine of four reptiles. GLU-IR cells exhibited a limited and species-dependent variant distribution in the GIT of four reptiles. SP-IR cells were found throughout the GIT except for jejunum in E. elegans and showed a restricted distribution in the GIT of G. japonicus and S. indicus. In the GIT of four reptiles the region with the highest degree of cell type heterogeneity was pylorus and most types of GI endocrine cells along the GIT showed the peak density in pylorus as well. CONCLUSION： Some common and unique features of the distribution and morphology of different types of GI endocrine cells are found in four reptiles. This common trait may reflect the similarity in digestive physiology of various vertebrates.

Adaptive changes of gastro-entero-pancreatic system endocrine cells in the black-spotted pond frog Rana nigromaculata after fasting

Changes in distribution density,morphology and secretory content of endocrine cells in the gastro-entero-pancreatic system of black-spotted frogs Rana nigromaculata before and after fasting were investigated using immunohistochemistry and antisera to six gut hormones.Six types of endocrine cells were detected in the digestive tract of Rana nigromaculata,including 5-hydroxytryptamine(5-HT),gastrin(GAS),somatostatin(SOM),glucagon(GLU),pancreatic polypeptide(PP)and vasoactive intestinal polypeptide(VIP)cells.After fasting,the density of 5-HT cells in the esophagus,cardia and fundus,GAS cells in the fundus and pylorus,PP cells in the fundus decreased significantly(P<0.01),while SOM cells in the cardia,GLU cells in the rectum increased significantly(P<0.01).The cytoplasmic processes of 5-HT cells became shorter or not detectable.The secretory content of GAS cells reduced in the cardia.The positive immunostaining reaction in the perinuclear region of SOM cells in the cardia,fundus and pylorus became weaker,while the staining intensity in the periphery of these cells became stronger.VIP cells were not detectable in the whole digestive tract after fasting.Five types of endocrine cells were found in the pancreas of Rana nigromaculata,including 5-HT,GAS,SOM,GLU and PP cells.After fasting,the density of 5-HT cells decreased slightly(P>0.05),while SOM,GAS,GLU and PP cells increased significantly(P<0.01).Furthermore,the secretory content of GLU cells increased significantly.Considering their functionalities,our results indicate that the changes of GEP endocrine cells in Rana nigromaculata responded adaptively to starvation-induced stress.

Changes of the gastric endocrine cells in the C57BL/6 mouse after implantation of murine lung carcinoma: An immunohistochemical quantitative study

AIM: The regional distributions and relative frequencies of some gastric endocrine cells of C57BL/6 mice were studied by immunohistochemical method using seven types of specific antisera against chromogranin A (CGA), serotonin, somatostatin, gastrin, cholecystokinin (CCK)-8, glucagon and human pancreatic polypeptide (HPP) after subcutaneous implantation of murine lung carcinoma (3LL) cells. METHODS: The experimental animals were divided into two groups, one is non-implanted sham and the other is 3LL-implanted group. Samples were collected from the two regions of stomach (fundus and pylorus) at 28 d after implantation of 3LL cells (1x105 cell/mouse). RESULTS: In this study, all the seven types of immunoreactive (IR) cells were identified except for HPP. Most of these IR cells in the gastric portion were generally spherical or spindle in shape (open-type cell) while cells showing round in shape (closed-type cell) were found occasionally. The regional distributions of gastric endocrine cells in the 3LL-implanted group were similar to those of non-implanted sham. However, significant decreases of some types of IR cells were detected in 3LL-implanted group compared to those of non-implanted sham. In addition, the IR cells showing degranulation were numerously detected in 3LL-implanted group. CGA-, serotonin- and somatostatin-IR cells in the fundus and pylorus regions, and gastrin-IR cells in the pylorus regions of 3LL-implanted groups significantly decreased compared to those of non-implanted sham. However, no changes on frequencies of CCK-8- and glucagon-IR cells were demonstrated between 3LL-implanted and non-implanted groups. CONCLUSION: Endocrine cells are the anatomical units responsible for the production of gut hormones, and the change in their density would reflect a change in the capacity of producing these hormones. Implantation of tumor cell mass (3LL) induced severe quantitative changes of gastric endocrine cell density, and the abnormality in density of gastric endocrine cells may contribute to the development of gastrointestinal symptoms such as anorexia and indigestion, frequently encountered in patients with cancer.

STUDY ON PROLIFERATIVE ACTIVITY OF ENDOCRINE CELLS IN GASTRIC CARCINOMA

Endocrine cell(EC) in 11 cases picked up from 56 cases of gastric carcinoma were observed by double immunohistochemical method using chromogramnin A(CgA) and proliferating cell nuclear antigen(PCNA).The endocrine cells were recognized by a antibody to CgA and the proliferative activity by a monoclonal antibody to PCNA.11 cases CgA positive GC cells with PCNA incorporation was in 51/4069(0-3%) with an average 1.25%.By contrast PCNA reaction was positive in 31.9±14.7% of CgA negative GC cells.It suggests that there were a few cell in S and G1 phase and most of them in G0 phase.

Changes of the intestinal endocrine cells in the C57BL/6 mouse after implantation of murine lung carcinoma (3LL): An immunohistochemical quantitative study

AIM: To study the distributions and frequencies of intestinal endocrine cells in the C57BL/6 mouse with immunohistochemical method using seven types of specific antisera against chromogranin A (CGA), serotonin,somatostatin, glucagons, gastrin, cholecystokinin (CCK)-8 and human pancreatic polypeptide (hPP) after abdominal subcutaneous implantation of murine lung carcinoma (3LL).METHODS: The experimental animals were divided into two groups, one is non-implanted Sham and the other is 3LL-implanted group. Samples were collected from six regions of intestinal tract at 28th d after implantation of 3LL cells (1×105 cell/mouse).RESULTS: In this study, five types of immunoreactive (IR) cells were identified except for gastrin and hPP. The regional distributions of the intestinal endocrine cells in the 3LL-implanted group were similar to those of the non-implanted Sham. However, significant decreases of IR cells were detected in 3LL-implanted group compared to those of non-implanted Sham. CGA- and serotonin-IR cells significantly decreased in 3LL-implanted groups compared to that of non-implanted Sham. Somatostatin-IR cells in the jejunum and ileum and CCK-8-IR cells in the jejunum of 3LL-implanted groups significantly decreased compared to that of non-implanted Sham. In addition,glucagon-IR cells were restricted to the ileum and colon of non-implanted Sham.CONCLUSION: Implantation of tumor cell mass (3LL)induced severe quantifiable changes of intestinal endocrine cell density and the abnormality in density of intestinal endocrine cells may contribute to the development of gastrointestinal symptoms such as anorexia and indigestion, frequently encountered in patients with cancer.

INFLUENCE OF ELECTROACUPUNCTURE OF “HUANTIAO” (GB 30) AT DIFFEREN TIME ON DUODENTAL ENDOCRINE CELLS IN RATS

Objective： To observe the influence of electroacupuncture （EA） at different time in a clay on the number of duodenal endocrine cells （argentaffin cells） in rats. Methods. Forty-eight male Wistar rats were evenly randomized into control and electroaoupuncfure （EA） groups which were further divided into 5：00, 11：00, 17：00 and 23：00 subgroups respectively. EA （4- 16 Hz in the frequency, 3 V in the strength, intermittent dense-sparse waves, and duration of 20 min） was applied to bilateral “Huan- tiao” （环跳 GB 30） at 5：00 o＇clock, 11：00 o＇clock, 17：00 o＇clock and 23：00 o＇clock separately for different subgroups. After EA, the animals were killed at once for sempling the middle part of cluodenum which was fixed in 10% formalin for 2 hours, then embed in paraffin. The tissue was cut into sections （ 10 μm）, mounted on glass slides and then processed according to Grimelius＇s methods. Results： The rumber of argentaffin cells in EA group was significantly fewer than that in control group at the same timewindow （23：00, P〈0.05）. No significant differences were found between control and EA groups in the number of cells at other time window （5：00, 11：00 and 17：00 o＇clock, P〉0.05）, suggesting that EA of “Huantiao”can markedly promote the secretion activity of endocrine cells at 11：00 o＇clock during night ferent time window in a day. Conclusion. The results suggest that the effects of EA are different at clifferent time window in a day.

THE ENDOCRINE CELLS OF EXTRATUMORAL MUCOSA IN RELATION TO THE CARCINOMA IN STOMACH

One hundred and sixty-one surgically resected gastric carcinomas and 5 stomachs obtained at necropsy were evaluated using anti chromogranin A (CgA). CgA-Positive cells were found in 55 of 161 gastric carcinoma. Endocrine cells (EC) of the 55 cases of rumors and extratumoral mucosa and 5 normal gastric mucosa were distinguished by immunoreastive gastrin (CAST), somatostatin (SS), serotonin (SERO), calcitonin (CT), ACTH, human chorionic gonadotropin (HCG) , glucagon (GLU) , pancreatic polypeptide (PP), bombesin (BOM). Each type EC in extratumoral mucosa was quantitated by Image analyser. TWO variants of changes of EC were identified on the basis of presence or absence of associated antral atrophy. In the group of antral atrophy, amount of G cells decreases than normal control (58. 7mm2, P<0. 001); D cells and BOM-positive cell also decrease; GLU-positive cells distributing in glands of intestinal metaplasia increase (18. 6/mm2, P<0. 001) in antral mucosa. There is not obvious change in the average thickness of fundic mucosa (1. 42mm, P>0. 05). Intestinal type carcinoma was more found in this group. G cell hyperplasia was observed in nontrophic antral extratumorel mucosa (211/mm2, P< 0. 001). G cell and D cell is in a ratio of about 14 to 1, however It is about 7. 6 to 1 in normal gastric antrum. BOM-positive cells are hyperplasia. The average thickness of fundic mucosa was found to be increased (1. 92mm, P<0.05). Diffuse type carcinoma was more found in this group. PP, ACTH, HCG-positive cells were discovered in the two groups. It suggests that endocrine substances may act as promoters of tumor growth and that different kinds of hormones may play a effect on different type of gastric carcinoma.

Immunohistochemical Location of Six Kinds of Endocrine Cell from Digestive Tract of Misgurnus anguillicaudatus

[Objective] The study was to immunohistochemical localize the endocrine cells from digestive tract of Misgurnus [ Method ] Using six gastrointestinal hormone antisera, the endocrine cells from digestive tract of M. anguillicaudatus was localized. [ Result ]The 5-hydroxytryptamine immunoreactive（5-HT-IR） cells distribute in oesophagus, foregut and midgut; the distribution density was determined to be forepart of foregut 〉 oesophagus and hindpart of foregut 〉 gut, and the differences in the three density gradients reached significant level. Like PP-IR, SS-IR cells were observed mostly in oesophagus, followed by hindpart of foregut, least in forepart of foregut, but never found in gut and hindgut. The three kinds of immunocompetent cells Gas-IR, Glu-IR and SP-IR were not detected in each part of digestive tract. [ Conctusion] This study may provide basic data for studying the nutritional and digestive physiology, as well as the preparation of meridic diets for M. anguillicaudatus.

Streptozotocin-induced expression of Ngn3 and Pax4 in neonatal rat pancreatic α-cells

AIM： To investigate the mechanism behind β-cell regeneration in neonatal rat pancreas treated with strep- tozotocin （STZ）. METHODS： Neonatal Sprague Dawley rats were intra- peritoneally injected with 70 mg/kg STZ. Body weight, pancreas weight and blood glucose were recorded every two days after the treatment. To identify the expression and location of transcription factors in the rat pancreas, double immunofluorescent staining was performed using antibodies to specific cell markers and transcription factors. RESULTS： Expression of Neurogenin 3 （Ngn3）, a marker for endocrine precursor cells, was observed by immunofluorescence in a few β-cells and many a-cells. The expression reached a peak 12 d after treatment. Pax4, a transcription factor that lies downstream of Ngn3 and plays an important role in β-cell differentiation, was also expressed in the α-cells of STZ-treated rats. We did not observe significant changes in Nkx6.1, which is essential for β-cell maturation in the treated rats. CONCLUSION： α-cells dedifferentiated into endocrine precursor cells and acquired the ability to dedifferentiate in the neonatal rat pancreas after STZ treatment.

Pathologic pancreatic endocrine cell hyperplasia

Pathologic hyperplasia of various pancreatic endocrine cells is rare but has been long known.β cell hyperplasia contributes to persistent hyperinsulinemic hypoglycemia of infancy,which is commonly caused by mutations in the islet ATP-sensitive potassium channel,and to noninsulinoma pancreatogenous hypoglycemia in adults,which may or may not be associated with bariatric surgery.α cell hyperplasia may cause glucagonoma syndrome or induce pancreatic neuroendocrine tumors.An inactivating mutation of the glucagon receptor causes α cell hyperplasia and asymptomatic hyperglucagonemia.Pancreatic polypeptide cell hyperplasia has been described without a clearly-characterized clinical syndrome and hyperplasia of other endocrine cells inside the pancreas has not been reported to our knowledge. Based on morphological evidence,the main pathogenetic mechanism for pancreatic endocrine cell hyperplasia is increased endocrine cell neogenesis from exocrine ductal epithelium.Pancreatic endocrine cell hyperplasia should be considered in the diagnosis and management of hypoglycemia,elevated islet hormone levels,and pancreatic neuroendocrine tumors.Further studies of pathologic pancreatic endocrine cell hyperplasia will likely yield insights into the pathogenesis and treatment of diabetes and pancreatic neuroendocrine tumors.

Effects of bisphenol compounds on the growth and epithelial mesenchymal transition of MCF-7 CV human breast cancer cells

Bisphenol-A（BPA） has been considered as an endocrine disrupting chemical（EDC） because it can exert estrogenic properties.For bisphenol-S（BPS） and bisphenol-F（BPF） that are BPA analogs and substitutes,their risk to estrogendependent cancer has been reported rarely compared with the numerous cases of BPA.In this study,we examined whether BPA,BPS,and BPF can lead to the proliferation,migration,and epithelial mesenchymal transition（EMT） of MCF-7 clonal variant（MCF-7 CV） breast cancer cells expressing estrogen receptors（ERs）.In a cell viability assay,BPA,BPS,and BPF significantly increased proliferation of MCF-7 CV cells compared to control（DMSO） as did17β-estradiol（E2）.In Western blotting assay,BPA,BPS,and BPF enhanced the protein expression of cell cycle progression genes such as cyclin D1 and E1.In addition,MCF-7 CV cells lost cell to cell contacts and acquired fibroblast-like morphology by the treatment of BPA,BPS,or BPF for 24 hours.In cell migration assay,BPA,BPS,and BPF accelerated the migration capability of MCF-7 CV cells as did E2.In relation with the EMT process,BPA,BPS,and BPF increased the protein expression of N-cadherin,while they decreased the protein expression of Ecadherin.When BPA,BPS,and BPF were co-treated with ICI 182,780,an ER antagonist,proliferation effects were reversed,the expression of cyclin D1 and cyclin E1 was downregulated,and the altered cell migration and expression of N-cadherin and E-cadherin by BPA,BPS,and BPF were restored to the control level.Thus,these results imply that BPS and BPF also have the risk of breast cancer progression as much as BPA in the induction of proliferation and migration of MCF-7 CV cells by regulating the protein expression of cell cycle-related genes and EMT markers via the ER-dependent pathway.

Immunocytochemical Localization of Glucagon and Insulin Cells in Eutropis carinata with Respect to Reproductive Cycle

The pancreas of Eutropis carinata was studied immunocytochemically for the presence and topographic distribution of glucagon and insulin cells during annual reproductive cycles. The study revealed paracrine arrangement of the two types of ceils. The immunolocalized pancreatic cells revealed significant differences in mean numbers during different periods of reproduction. The numbers of glucagon-immunoreactive （GIR） and insulin-immunoreactive （IIR） cells were highest during the recrudesceut period which corresponded with low serum glucose level. Between the two immunoreactive cells, the GIR cells were predominant. Morphological differences between the two cells were observed by electron microscopy after staining with uranyl acetate and lead citrate. Serum glucose showed that cyclic change was highest during the reproductive period.

Irritable bowel syndrome:Diagnosis and pathogenesis

Irritable bowel syndrome (IBS) is a common gastro-intestinal (GI) disorder that considerably reduces the quality of life. It further represents an economic burden on society due to the high consumption of healthcare resources and the non-productivity of IBS patients. The diagnosis of IBS is based on symptom assessment and the Rome Ⅲ criteria. A combination of the Rome Ⅲ criteria, a physical examination, blood tests, gastros-copy and colonoscopy with biopsies is believed to be necessary for diagnosis. Duodenal chromogranin A cell density is a promising biomarker for the diagnosis of IBS. The pathogenesis of IBS seems to be multifactorial, with the following factors playing a central role in the pathogenesis of IBS:heritability and genetics, dietary/intestinal microbiota, low-grade inflammation, and disturbances in the neuroendocrine system (NES) of the gut. One hypothesis proposes that the cause of IBS is an altered NES, which would cause abnormal GI motility, secretions and sensation. All of these abnormalities are characteristic of IBS. Alterations in the NES could be the result of one or more of the following:genetic factors, dietary intake, intestinal flora, or lowgrade inflammation. Post-infectious IBS (PI-IBS) and inflammatory bowel disease-associated IBS (IBD-IBS) represent a considerable subset of IBS cases. Patients with PI-and IBD-IBS exhibit low-grade mucosal inflammation, as well as abnormalities in the NES of the gut.

Recent developments in the pathophysiology of irritable bowel syndrome

Irritable bowel syndrome(IBS) is a common gastrointestinal disorder, the pathophysiology of which is not completely known, although it has been shown that genetic/social learning factors, diet, intestinal microbiota, intestinal low-grade inflammation, and abnormal gastrointestinal endocrine cells play a major role. Studies of familial aggregation and on twins have confirmed the heritability of IBS. However, the proposed IBS risk genes are thus far nonvalidated hits rather than true predisposing factors. There is no convincing evidence that IBS patients suffer from food allergy/intolerance, with the effect exerted by diet seemingly caused by intake of poorly absorbed carbohydrates and fiber. Obesity is a possible comorbidity of IBS. Differences in the microbiota between IBS patients and healthy controls have been reported, but the association between IBS symptoms and specific bacterial species is uncertain. Low-grade inflammation appears to play a role in the pathophysiology of a major subset of IBS, namely postinfectious IBS. The density of intestinal endocrine cells is reduced in patients with IBS, possibly as a result of genetic factors, diet, intestinal microbiota, and low-grade inflammation interfering with the regulatory signals controlling the intestinal stem-cell clonogenic and differentiation activities. Furthermore, there is speculation that this decreased number of endocrine cells is responsible for the visceral hypersensitivity, disturbed gastrointestinal motility, and abnormal gut secretion seen in IBS patients.

Is irritable bowel syndrome an organic disorder?

Irritable bowel syndrome(IBS) is a common gastrointestinal disorder that is generally considered to be functional because there appears to be no associated anatomical defect. Stress and psychological factors are thought to play an important role in IBS. The gut neuroendocrine system(NES),which regulates all functions of the gastrointestinal tract,consists of endocrine cells that are scattered among the epithelial cells of the mucosa,and the enteric nervous system. Although it is capable of operating independently from the central nervous system(CNS),the gut NES is connected to and modulated by the CNS. This review presents evidence for the presence of an anatomical defect in IBS patients,namely in the gastrointestinal endocrine cells. These cells have specialized microvilli that project into the lumen and function as sensors for the luminal content and respond to luminal stimuli by releasing hormones into the lamina propria,which starts a chain reaction that progresses throughout the entire NES. The changes in the gastrointestinal endocrine cells observed in IBS patients are highly consistent with the other abnormalities reported in IBS patients,such as visceral hypersensitivity,dysmotility,and abnormal secretion.

Synchronous occurrence of carcinoid, signet-ring cell carcinoma and heterotopic pancreatic tissue in stomach: A case report and literature review

We presented an unusual case with coexistence of carcinoid, signet-ring cell carcinoma （SRC） and heterotopic pancreatic tissue in stomach. Gastroscopic examination of this 63-year-old male patient showed multiple protrusions in gastric corpus near the greater curvature, identified by subsequent biopsy as carcinoid, Distal subtotal gastrectomy was performed, Histological and immunohistochemical examinations showed a carcinoid tumor in gastric corpus near the greater curvature, an intramucosal SRC at the lesser curvature of corpus and heterotopic pancreatic tissue in muscularis propria of the antrum at the lesser curvature with hyperplasia of peripheral endocrine cells producing multiple pancreatic hormones, We reviewed the literatures on clinicopathological characteristics and the differential diagnosis of the above three abnormalities, and concluded that the carcinoid in corpus near the greater curvature and SRC in the lesser curvature are independent lesions; the loci of endocrine cells in the muscularis propria and serosa are hyperplastic lesions from the heterotopic pancreatic tissue, rather than dissemination of carcinoid in corpus.

Review:Recent advances in the artificial endocrine system

The artificial endocrine system (AES) is a new branch of natural computing which uses ideas and takes inspiration from the information processing mechanisms contained in the mammalian endocrine system. It is a fast growing research field in which a variety of new theoretical models and technical methods have been studied for dealing with complex and significant problems. An overview of some recent advances in AES modeling and its applications is provided in this paper, based on the major and latest works. This review covers theoretical modeling, combinations of algorithms, and typical application fields. A number of challenges that can be undertaken to help move the field forward are discussed according to the current state of the AES approach.

Adult Onset Retinoblastoma： A Case Report

INTRODUCTION Retinoblastoma usually presents in children younger than 5 years.Adult retinoblastoma is rare,and diagnosis is usually made at a fairly advanced stage.We report a case with whitish,elevated,vascularized retinal mass and vitreous seeding diagnosed as undifferentiated retinoblastoma.