The Effect of Tuberculosis Infection on Pancreatic Beta-Cell Function in Patients with Type 2 Diabetes Mellitus

Objective: The aim of this study is to investigate how individuals with type 2 diabetes mellitus’ pancreatic β-cell function index and insulin resistance index are affected by tuberculosis infection. Methods: The study group consisted of 89 patients with type 2 diabetes mellitus and tuberculosis infection who were admitted to Jingzhou Chest Hospital between March 2019 and March 2021. Gender and duration of diabetes were matching conditions. The control group was made up of 89 patients with type 2 diabetes who were admitted to Jingzhou Central Hospital’s endocrinology department during the same period. The two patient groups provided general information such as gender, age, length of diabetes, and blood biochemical indexes such as glycosylated hemoglobin (HbA1c), fasting glucose (FPG), and fasting C-peptide (FC-P). The HOMA calculator was used to calculate the HOMA-β and the HOMA-IR, and intergroup comparisons and correlation analyses were carried out. Results: Regarding gender, age, disease duration, FC-P, and HbA1c, the differences between the two groups were not statistically significant (P > 0.05). However, BMI, FPG, HOMA-β, and HOMA-IR showed statistically significant differences (P < 0.05). In comparison to the control group, the study group’s HOMA-β was lower and its HOMA-IR was greater. According to Spearman’s correlation analysis, HOMA-β had a negative association (P th FPG, HbA1c, and the length of the disease, and a positive correlation with BMI and FC-P. A positive correlation was found between HOMA-IR and BMI, FPG, and FC-P (P < 0.01), as well as a correlation with the length of the disease (P > 0.05) and HbA1c. Conclusions: In type 2 diabetes mellitus combined with tuberculosis infection, the patients had higher FPG levels and lower FC-P levels, the secretory function of pancreatic β-cells was more severely impaired, and insulin resistance was more obvious.

A Study on Enhancing Pancreatic Islet Function in Type 2 Diabetes and Coronary Heart Disease Patients with Liraglutide and Metformin Combination Therapy

Objective:To investigate the impact of combining liraglutide with metformin on the enhancement of pancreatic islet function in patients with type 2 diabetes and coronary heart disease.Methods:60 patients with type 2 diabetes and coronary heart disease admitted from February 2022 to August 2023 were selected as research subjects.They were randomly assigned to either control or treatment groups,with 30 patients in each.The control group received metformin alone,while the treatment group received liraglutide in combination with metformin.Various indicators,including blood sugar levels,pancreatic islet function,and cardiac function between the two groups were compared.Results:The results of FPG,2hPG,HbA1c,HOMA-IR,NT-proBNP,and LVEDD in the treatment group were lower than those in the control group,whereas the values of FINS,HOMA-β,E/A,and LVEF in the treatment group were higher than those in the control group(P<0.05).Conclusion:The use of liraglutide in combination with metformin significantly benefits patients with type 2 diabetes and coronary heart disease.It leads to improved pancreatic islet function,better blood sugar control,and enhanced cardiac function.This combination therapy is recommended for clinical adoption.

STUDIES OF EFFECTS OF PORTASYSTEMIC SHUNT ON THE FUNCTION OF HEPATIC AND PANCREATIC ISLET CELLS

The present study was aimed at dynamic observation of the ef fects of end to side portacaval shunt (PCS) and end to side mesocaval shunt (MCS) in dogs on the functions of the liver and pancreatic islet cells. According to correlation between the changes of plasma insulin level in the portal vein and hepatic flow and liver morphology after PCS and MCS, we conclude that the depletion of hepatic flow is the major factor in the deterioration of liver functions. The levels of insulin and glucagon in both the peripheral vein and the portal vein were decreased after PCS and MCS. There was also depletion of pancreatic islet A and B cells and vacuolar degeneration of the pancreas. These changes were more signifcant in PCS than in MCS, suggesting that portasystemic shunt, especially total portasystemie shunt, might damage pancreatic endocrine functions.

Isolation, Culture and Induced Differentiation of Fetal Porcine Islet Derived Pancreatic Stem Cell

To isolate and culture the porcine pancreatic stem cells and investigate their function, the fetal porcine pancreatic stem cells were isolated by the method of suspending plus adhering culture. The isolated cells were then identified by immunohistochemical staining, and their culture viability measured through the MTT method in vitro. This induced them to differentiate into endocrine cells and detect their function. The isolated IPSCS did not express nestin, but expressed CK-19, a marker of ductal epithelia cells and ct-actin, a smooth muscle marker, demonstrating the growth characteristics of ES-like cells, and strong proliferative ability, after 18 passages. They could excrete insulin, and showed ultrastructure changes after being induced. Porcine pancreatic stem cells can be isolated by this method, induced to form islet-like clusters, and can secret insulin.

Expression of stem cell markers CK-19 and PDX-1mRNA in pancreatic islet samples of different purity from rats

BACKGROUND: Islet stem cells are more or less retained in the procedure of islet isolation and purification, and are transplanted together with islet grafts. Keratoprotein (CK-19) and pancreatic duodenal hox gene 1 (PDX-1) are markers of stem cells. This study was undertaken to examine the expression of these markers in pancreatic islet samples of different purity from rats. METHODS: A total of 30 male Sprague-Dawley rats were randomly assigned to 3 groups to undergo perfusion with V-type collagenase via the pancreatic duct, then the pancreas was excised, diced, shaken, digested and centrifuged to obtain islet sediments. The sediment from group A was not purified, while that from group B was purified with 25% Ficoll-400 and that from group C with 25% and 11% Ficoll-400. RNA was extracted from the different islet samples for reverse transcriptase-polymerase chain reaction (RT-PCR). The expression of the pancreatic stem cell markers CK-19 and PDX-1 was assessed. RESULTS: The purity of islets in samples was (43.6 +/- 6.29)% in group A; (65.3 +/- 4.40)% in group B; and (77.6 +/- 6.36)% in group C (P<0.05). The expression of CK-19 and PDX-1 mRNA was significantly higher in group A than in groups B and C, but group C showed the lowest level of expression. CONCLUSION: The expression of CK-19 and PDX-1 mRNA in islet samples of different purity suggests the presence of stem cells in all islet samples.

Six-year follow-up of pancreatic β cell function in adults with latent autoimmune diabetes

AIM: To investigate the characteristics of the progression of islet β cell function in Chinese latent autoimmune diabetes in adult (LADA) patients with glutamic acid decarboxylase antibody (GAD-Ab) positivity, and to explore the prognostic factors for β cell function. METHODS: Forty-five LADA patients with GAD-Ab positivity screened from phenotypic type 2 diabetic (T2DM) patients and 45 T2DM patients without GAD-Ab matched as controls were followed-up every 6 mo. Sixteen patients in LADA1 and T2DM1 groups respectively have been followed-up for 6 years, while 29 patients in LADA2 and T2DM2 groups respectively for only 1.5 years. GAD-Ab was determined by radioligand assay, and C-peptides (CP) by radioimmune assay.RESULTS: The percentage of patients whose fasting CP(FCP) decreased more than 50% compared with thebaseline reached to 25.0% at 1.5th year in LADA1 group, and FCP level decreased (395.8±71.5 vs 572.8±72.3 pmol/L, P＜0.05) at 2.5th year and continuously went down to the end of follow-up. No significant changes of the above parameters were found in T2DM1 group. The average decreased percentages of FCP per year in LADA and T2DM patients were 15.8% (4.0-91.0%) and 5.2% (-3.5 to 35.5%, P= 0.000) respectively. The index of GAD-Ab was negatively correlated with the FCP in LADA patients (rs= -0.483, P = 0.000). The decreased percentage of FCP per year in LADA patients were correlated with GAD-Ab index, body mass index (BMI) and age at onset (rs = 0.408, -0.301 and -0.523 respectively, P＜0.05). Moreover, GAD-Ab wasthe only risk factor for predicting βcell failure in LADA patients (B = 1.455, EXP (B) = 4.283, P = 0.023). CONCLUSION: The decreasing rate of islet β cell function in LADA, being highly heterogeneous, is three times that of T2DM patients. The titer of GAD-Ab is an important predictor for the progression of islet β cell function, and age at onset and BMI could also act as the predictors.

Differentiation of fetal pancreatic stem cells into neuron-like and islet-like cells in vitro

Pancreatic stem cells were isolated and cultured from aborted human fetal pancreases of gestational age 14-20 weeks. They were seeded at a density of 1 × 104 in serum-free media for differentiation into neuron-like cells, expressing β-tubulin III and glial fibrillary acidic protein. These neuron-like cells displayed a synapse-like morphology and appeared to form a neuronal network. Pancreatic stem cells were also seeded at a density of 1 × 105 for differentiation into islet-like cells, expressing insulin and glucagon, with an islet-like morphology. These cells had glucose-stimulated secretion of human insulin and C-peptide. Results suggest that pancreatic stem cells can be differentiated into neuron-like and islet-like cells.

Pancreatic fat and β-cell function in overweight/obese children with nonalcoholic fatty liver disease

AIM: To analyze the associations of pancreatic fat with other fat depots and β-cell function in pediatric nonalcoholic fatty liver disease(NAFLD).METHODS: We examined 158 overweight/obese children and adolescents, 80 with NAFLD [hepatic fat fraction(HFF) ≥ 5%] and 78 without fatty liver. Visceral adipose tissue(VAT), pancreatic fat fraction(PFF) and HFF were determined by magnetic resonance imaging. Estimates of insulin sensitivity were calculated using the homeostasis model assessment of insulin resistance(HOMA-IR), defined by fasting insulin and fasting glucose and whole-body insulin sensitivity index(WBISI), based on mean values of insulin and glucose obtained from oral glucose tolerance test and the corresponding fasting values. Patients were considered to have prediabetes if they had either:(1) impaired fasting glucose, defined as a fasting glucose level ≥ 100 mg/d L to < 126 mg/d L;(2) impaired glucose tolerance, defined as a 2 h glucose concentration between ≥ 140 mg/d L and < 200 mg/d L; or(3) hemoglobin A1 c value of ≥ 5.7% to < 6.5%.RESULTS: PFF was significantly higher in NAFLD patients compared with subjects without liver involvement. PFF was significantly associated with HFF and VAT, as well as fasting insulin, C peptide, HOMA-IR, and WBISI. The association between PFF and HFF was no longer significant after adjusting for age, gender, Tanner stage, body mass index(BMI)-SD score, and VAT. In multiple regression analysis withWBISI or HOMA-IR as the dependent variables, against the covariates age, gender, Tanner stage, BMI-SD score, VAT, PFF, and HFF, the only variable significantly associated with WBISI(standardized coefficient B,-0.398; P = 0.001) as well as HOMA-IR(0.353; P = 0.003) was HFF. Children with prediabetes had higher PFF and HFF than those without. PFF and HFF were significantly associated with prediabetes after adjustment for clinical variables. When all fat depots where included in the same model, only HFF remained significantly associated with prediabetes(OR = 3.38; 95%CI: 1.10-10.4; P = 0.034).CONCLUSION: In overweight/obese children with NAFLD, pancreatic fat is increased compared with those without liver involvement. However, only liver fat is independently related to prediabetes.

Imaging pancreatic islet cells by positron emission tomography

It was estimated that every year more than 30000 persons in the United States- approximately 80 people per day- are diagnosed with type 1 diabetes(T1D). T1 D is caused by autoimmune destruction of the pancreatic islet(β cells) cells. Islet transplantation has become a promising therapy option for T1 D patients, while the lack of suitable tools is difficult to directly evaluate of the viability of the grafted islet over time. Positron emission tomography(PET) as an important non-invasive methodology providing high sensitivity and good resolution, is able to accurate detection of the disturbed biochemical processes and physiological abnormality in living organism. The successful PET imaging of islets would be able to localize the specific site where transplanted islets engraft in the liver, and to quantify the level of islets remain alive and functional over time. This information would be vital to establishing and evaluating the efficiency of pancreatic islet transplantation. Many novel imaging agents have been developed to improve the sensitivity and specificity of PET islet imaging. In this article, we summarize the latest developments in carbon-11, fluorine-18, copper-64, and gallium-68 labeled radioligands for the PET imaging of pancreatic islet cells.

THE CHANGES OF PANCREATIC ACINAR CELL FUNCTION IN ACUTE NECROTIZING PANCREATITIS OF RATS

ObjectiFe To evaluate the changes of pancreatic acinar cell functions in the rats with acutenecrotizing pancreatitis (ANP). methods Seventy SD rats were randomized into two groups: experimental group(n=35) and control group (n=35). To prepare the experimental model, the retrograde injection of 5% sodiumtaurocholate into the pancreatic duct was used for inducing ANP. Radioactive tracing by L -3H-phenylalanineand autoradiography were performed for scoring the differences of changes of amino acid uptake, enzyme-proteinsynthesis and output from acinar cells in rats between both groups. Results No changes were observed in aminoacid uptake and enzyme -protein synthesis in rats with dotted and haemorrhagic necrotizing foci as compared withcontrol group. However, accumulated zymogen granules in the interstitial of acinar cells were seen in theexperimental group. Conclusion It indicates that in experimental ANP rats, the functions of acinar cells in bothamino acid uptake and protein synthesis were essentially normal, but the pathway of enzyme output was affectedinto ectopic secretion through the bottom or lateral cellular membrane of pancreatic acinar cell.

Pancreatic stellate cell: Pandora's box for pancreatic disease biology

Pancreatic stellate cells(PSCs) were identified in the early 1980 s, but received much attention after 1998 when the methods to isolate and culture them from murine and human sources were developed. PSCs contribute to a small proportion of all pancreatic cells under physiological condition, but are essential for maintaining the normal pancreatic architecture. Quiescent PSCs are characterized by the presence of vitamin A laden lipid droplets. Upon PSC activation, these perinuclear lipid droplets disappear from the cytosol, attain a myofibroblast like phenotype and expresses the activation marker, alpha smooth muscle actin. PSCs maintain their activated phenotype via an autocrine loop involving different cytokines and contribute to progressive fibrosis in chronic pancreatitis(CP) and pancreatic ductal adenocarcinoma(PDAC). Several pathways(e.g., JAK-STAT, Smad, Wnt signaling, Hedgehog etc.), transcription factors and mi RNAs have been implicated in the inflammatory and profibrogenic function of PSCs. The role of PSCs goes much beyond fibrosis/desmoplasia in PDAC. It is now shown that PSCs are involved in significant crosstalk between the pancreatic cancer cells and the cancer stroma. These interactions result in tumour progression, metastasis, tumour hypoxia, immune evasion and drug resistance. This is the rationale for therapeutic preclinical and clinical trials that have targeted PSCs and the cancer stroma.

Surgical treatment of nonfunctioning islet cell tumor: report of 41 cases

BACKGROUND: Nonfunctioning islet cell tumor (NIT)as a rare pancreatic endocrine neoplasm is characterized byunspecific clinical symptoms and is hard to diagnose. InChina, NIT accounts for 15%-41% in pancreatic endocrineneoplasms just next to insulinoma. In this study, weevaluated the surgical modalities of NIT.METHODS: From January 1978 through February 2002, 41patients with NIT were treated at the Department of Sur-gery of the First Affiliated Hospital, China Medical Univer-sity, Shenyang, China. Tumors in the head of the pancreaswere noted in 28 patients, and in the body or in the tail in13 patients. The mean diameter of the tumors was 10. 7cm. Fifteen patients underwent enucleation and 21 receivedpancreatectomy. Tumors were unresectable in 5 patientsbecause of extensive infiltration. The mean diameter was9.6 cm in patients treated by enucleation, 13.1 cm in thoseby pancreaticoduodenectomy, 9.9 cm in those by distalpancreatectomy, and 11.6 cm in those with unresectabletumors.RESULTS: The curative resection rate was 88% (n =36),and the complication rate after enucleation and pancreatec-tomy was 33% ( n = 5 ) and 14% (n=3), respectively. Nolocal recurrence was found after both enucleation and pan-createctomy. Liver metastases occurred in 3 patients treatedby enucleation.CONCLUSIONS: Both enucleation and pancreatectomy areeffective for NIT of the pancreas. No local recurrence hasbeen found in patients treated by the two surgical proce-dures. The complication rates of the two modalities arecomparable.

EFFECTS OF GLUCAGON ON ISLET β CELL FUNCTION IN PATIENTS WITH DIABETES MELLITUS

Objective To evaluate islet β cell response to intravenous glucagon （ a non-glucose secretagogue） stimulation in diabetes mellitus. Methods Nineteen patients with type 1 diabetes （T1 D） and 131 patients with type 2 diabetes （T2D） were recruited in this study. T2D patients were divided into two groups according to therapy： 36 cases treated with insulin and 95 cases treated with diet or oral therapy. The serum C-peptide levels were determined at fasting and six minutes after intra- venous injection of 1 mg of ghicagon. Results Both fasting and 6-minute post-ghicagon-stimulated C-peptide levels in T1D patients were significantly lower than those of T2D patients （0. 76±0. 36 ng/mL vs. 1.81±0. 78 ng/mL, P 〈 0.05 ; 0.88±0.42 ng/mL vs. 3.68±0. 98 ng/mL, P 〈 0. 05 ）. In T1D patients, the C-peptide level after injection of ghicagon was similar to the fasting level. In T2D, patients treated with diet or oral drug had a significantly greater fasting and stimulated C-peptide level than those patients received insulin therapy （2.45±0. 93 ng/mL vs. 1.61±0. 68 ng/mL, P 〈 0.05 ; 5.26±1.24 ng/mL vs. 2.15±0.76 ng/mL, P 〈 0.05 ）. The serum C-peptide level after ghicagon stimulation was positively correlated with C-peptide levels at fasting in all three groups （ r = 0.76, P 〈 0.05 ）. Conclusions The 6-minute ghicagon test is valuable in assessing the function of islet β cell in patients with diabetes mellitus. It is helpful for diagnosis and treatment of diabetes mellitus.

Pancreatic islet transplantation

Type 1 diabetes mellitus is an autoimmune disease,which results in the permanent destruction of β-cells of the pancreatic islets of Langerhans.While exogenous insulin therapy has dramatically improved the quality of life,chronic diabetic complications develop in a substantial proportion of subjects and these complications generally progress and worsen over time.Although intensive insulin therapy has proven effective to delay and sometimes prevent the progression of complications such as nephropathy,neuropathy or retinopathy,it is difficult to achieve and maintain long term in most subjects.Reasons for this diff iculty include compliance issues and the increased risk of severe hypoglycemic episodes,which are generally associated with intensification of exogenous insulin therapy.Clinical studies have shown that transplantation of pancreas or purified pancreatic islets can support glucose homeostasis in type 1 diabetic patients.Islet transplantation carries the special advantages of being less invasive and resulting in fewer complications compared with the traditional pancreas or pancreas-kidney transplantation.However,islet transplantation efforts have limitations including the short supply of donor pancreata,the paucity of experienced islet isolation teams,side effects of immunosuppressants and poor long-term results.The purpose of this article is to review recent progress in clinical islet transplantation for the treatment of diabetes.

In vitro pancreas duodenal homeobox-1 enhances the differentiation of pancreatic ductal epithelial cells into insulin-producing cells

AIM: To observe whether pancreatic and duodenal homeobox factor-1 enhances the differentiation of pancreatic ductal epithelial cells into insulin-producing cells in vitro. METHODS: Rat pancreatic tissue was submitted to digestion by collegenase, ductal epithelial cells were separated by density gradient centrifugation and then cultured in RPMI1640 medium with 10% fetal bovine serum. After 3-5 passages, the cells were incubated in a six-well plate for 24 h before transfection of recombination plasmid XlHbox8VP16. Lightcycler quantitative real-time RT-PCR was used to detect the expression of PDX-1 and insulin mRNA in pancreatic epithelial cells. The expression of PDX-1 and insulin protein was analyzed by Western blotting. Insulin secretion was detected by radioimmunoassay. Insulin- producing cells were detected by dithizone-staining. RESULTS: XlHbox8 mRNA was expressed in pancreatic ductal epithelial cells. PDX-1 and insulin mRNA as well as PDX-1 and insulin protein were signifi cantly increased in the transfected group. The production and insulin secretion of insulin-producing cells differentiated from pancreatic ductal epithelial cells were higher than those of the untransfected cells in vitro with a significant difference (1.32 ± 0.43 vs 3.48 ± 0.81, P < 0.01 at 5.6 mmol/L; 4.86 ± 1.15 vs 10.25 ± 1.32, P < 0.01 at 16.7 mmol/L). CONCLUSION: PDX-1 can differentiate rat pancreaticductal epithelial cells into insulin-producing cells in vitro. In vitro PDX-1 transfection is a valuable strategy for increasing the source of insulin-producing cells.

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.

Pancreatic fat in type 2 diabetes:Causal or coincidental?

Type 2 diabetes(T2D)is a multifactorial metabolic disorder affecting more than 450 million people across the globe.With the increasing prevalence of T2D and obesity,the role of fat accumulation at sites other than subcutaneous adipose tissue has received significant attention in the pathophysiology of T2D.Over the past decade and a half,a pressing concern has emerged on investigating the association of pancreatic fat accumulation or pancreatic steatosis with the development of disease.While a few reports have suggested a possible association between pancreatic fat and T2D and/or impaired glucose metabolism,a few reports suggest a lack of such association.Pancreatic fat has also been linked with genetic risk of developing T2D,prediabetes,reduced insulin secretion,and beta cell dysfunction albeit some confounding factors such as age and ethnicity may affect the outcome.With the technological advancements in clinical imaging and progress in assessment of pancreatic beta cell function,our understanding of the role of pancreatic fat in causing insulin resistance and development of various etiologies of T2D has significantly improved.This review summarizes various findings on the possible association of pancreatic fat accumulation with the pathophysiology of T2D.

Total pancreatectomy with islet cell transplantation vs intrathecal narcotic pump infusion for pain control in chronic pancreatitis

AIM: To evaluate pain control in chronic pancreatitis patients who underwent total pancreatectomy with islet cell transplantation or intrathecal narcotic pump infusion.METHODS: We recognized 13 patients who underwent intrathecal narcotic pump(ITNP) infusion and 57 patients who underwent total pancreatectomy with autologous islet cell transplantation(TP + ICT) for chronic pancreatitis(CP) pain control between 1998 and 2008 at Indiana University Hospital. All patients had already failed multiple other modalities for pain control and the decision to proceed with either intervention was made at the discretion of the patients and their treating physicians. All patients were evaluated retrospectively using a questionnaire inquiring about their pain control(using a 0-10 pain scale), daily narcotic dose usage, and hospital admission days for pain control before each intervention and during their last follow-up. RESULTS: All 13 ITNP patients and 30 available TP + ICT patients were evaluated. The mean age was approximately 40 years in both groups. The median duration of pain before intervention was 6 years and 7 years in the ITNP and TP + ICT groups, respectively. The median pain score dropped from 8 to 2.5(on a scale of 0-10) in both groups on their last follow up. The median daily dose of narcotics also decreased from 393 mg equivalent of morphine sulfate to 8 mg in the ITNP group and from 300 mg to 40 mg in the TP + ICT group. No patient had diabetes mellitus(DM) before either procedure whereas 85% of those who underwent pancreatectomy were insulin dependent on their last evaluation despite ICT. CONCLUSION: ITNP and TP + ICT are comparable for pain control in patients with CP however with high incidence of DM among those who underwent TP + ICT. Prospective comparative studies and longer follow up are needed to better define treatment outcomes.

Differentiation of Pancreatic Ductal Epithelial Cells into Insulin Like Cell Clusters in Chronic Pancreatitis

Background/Aim: Islet regeneration in chronic pancreatitis (CP) is relevant for managing the associated loss of endocrine function. Because ductal epithelial cells were earlier demonstrated to differentiate into pancreatic endocrine mass, we evaluated their proliferation and differentiation in chronic pancreatitis. Methods: Pancreatic ducts were obtained from surgically resected pancreata of 12 patients with chronic pancreatitis and 15 control subjects. CK19 positive ductal cells were evaluated for their proliferating and differentiating abilities upon immunostaining with Ki 67 and hormone positivity for insulin and glucagon, apart from monitoring Pdx 1 expression. Results: In comparison to the controls, a greater number of proliferating pancreatic ductal epithelial cells (PDECs) were observed under conditions of CP. The increase in Pdx1 expressing PDECs (22%) and proliferating Pdx1 expressing PDECs (30%) was significant (P < 0.04). Number of cells expressing insulin/glucagon in the exocrine ducts increased significantly in CP as compared to controls (P ?β?cell mass adjacent to the ducts increased by 28%.?Conclusion: Enhanced capability of PDECs to proliferate and differentiate into endocrine mass suggests that PDECs form a source of progenitors for cell based therapy in chronic pancreatitis.

Transcriptome Profiles and Gene Expression of Min6 Cells Are Altered by Pancreatic Stellate Cells

Aim: To identify the influence of pancreatic stellate cell (PSCs) secretions on gene expression profiles of Min6 cells by whole transcriptome sequencing. Methods: Pancreatic stellate cells (PSCs) were isolated from C57BL6J mice and propagated in vitro to acquire the activated phenotype. Total RNA was isolated from monocultured (MC) and PSC cocultured (CC) Min6 cells to prepare cDNA libraries, which were subjected to whole transcriptome sequencing for identifying differential expression of β-cell transcription factors (Pdx-1, Rfx6 and NeuroD1) related to insulin gene transcription and GSIS related genes such as Glut2, Gck, Abcc8, Kcnj11 and L-type Ca2+ channels (Cacnb2, Cacna1c). qRT-PCR was used to validate the gene expression. GSIS of Min6 cells was examined by estimating insulin levels in response to high glucose challenge. Results: Transcriptome analysis of discovery set revealed that coculture of Min6 cells with PSCs caused increased expression of β-cell specific genes (Ins1, Rfx6 and NeuroD1) concomitant with decreased expression of Pdx-1, MafA and Nkx2-2. Expression of GSIS associated genes (Glut2, Gck, Abcc8, Kcnj11 and Cacnb2) was decreased in such conditions. Validation by qRT-PCR in Min6 cells cocultured with PSCs revealed increased significant expression of Ins1 (2.1 ± 0.22 folds;p ≤ 0.001), Rfx6 (1.68 ± 0.23 folds;p ≤ 0.002) and NeuroD1 (0.96 ± 0.11 folds;p ≤ 0.01), accompanied by downregulation of Cacnb2 (-0.93 ± 0.57 folds;p ≤ 0.05). PSC secretions did not restore the GSIS from glucose unresponsive higher passage Min6 cells (MC: 1.33 ± 0.42;CC: 1.55 ± 0.72 pmol/mg protein;p = ns) upon high glucose stimulation. However, glucose responsive higher passage Min6 cells cocultured with PSCs presented increased insulin secretion (MC: 7.025 ± 0.64;CC: 14.84 ± 1.01 pmol/mg protein;p ≤ 0.04) concomitant with marginal increase of insulin contents. Conclusion: PSC secretions increase Ins1, Rfx6 and NeuroD1 gene expression, GSIS from glucose responsive Min6 cells, but do not restore the GSIS from glucose unresponsive Min6 cells.