Iron: a Strong Element in the Pathogenesis of Chronic Hyperglycaemia After Acute Pancreatitis

Associations of pancreas fat content and size with markers of iron metabolism

OBJECTIVE

To comprehensively investigate the associations of pancreas fat content and size with circulating markers of iron metabolism.

METHODS

A total of 116 individuals underwent magnetic resonance imaging and spectroscopy on a 3.0 Tesla scanner, exclusively for the purpose of the COSMOS research programme. Intra-pancreatic fat deposition, total pancreas volume, liver fat content, visceral and subcutaneous fat volumes were quantified. Plasma levels of hepcidin and ferritin were measured. Multiple linear regression analysis was conducted, adjusting for body mass index, age, and sex.

RESULTS

Total intra-pancreatic fat deposition was inversely associated with hepcidin (β = -0.54, 95 % confidence interval -1.02 to -0.07) whereas total pancreas volume was not associated with hepcidin (β = 0.36, 95 % confidence interval -7.12 to 7.84) in the most adjusted model. Neither total intra-pancreatic fat deposition (β = -0.03, 95 % confidence interval -0.39 to 0.33) nor total pancreas volume (β = -1.02, 95 % confidence interval -6.67 to 4.63) was associated with ferritin in the most adjusted model. Subcutaneous fat, visceral fat, and liver fat were not associated with hepcidin. Subcutaneous fat was inversely associated with ferritin (β = -0.06, 95 % CI -0.11 to -0.01) whereas visceral fat (β = 0.05, 95 % CI -0.01 to 0.14) and liver fat (β = 0.09, 95 % CI -0.04 to 0.34) were not associated with ferritin in the most adjusted model.

CONCLUSIONS

Increased intra-pancreatic fat deposition, but not other fat depots, is associated with reduced circulating levels of hepcidin. Deranged iron metabolism may play a role in the pathogenesis of fatty change of the pancreas.

Ferroptosis: potential targets and emerging roles in pancreatic diseases

Ferroptosis is a newly discovered form of regulatory cell death characterized by excessive iron-dependent lipid peroxidation. In the past decade, significant breakthroughs have been made in comprehending the features and regulatory mechanisms of ferroptosis, and it has been confirmed that ferroptosis plays a pivotal role in the pathophysiological processes of various diseases, including tumors, inflammation, neurodegenerative diseases, and infectious diseases. The pancreas, which is the second largest digestive gland in the human body and has both endocrine and exocrine functions, is a vital organ for controlling digestion and metabolism. In recent years, numerous studies have confirmed that ferroptosis is closely related to pancreatic diseases, which is attributed to abnormal iron accumulation, as an essential biochemical feature of ferroptosis, is often present in the pathological processes of various pancreatic exocrine and endocrine diseases and the vulnerability of the pancreas to oxidative stress stimulation and damage. Therefore, comprehending the regulatory mechanism of ferroptosis in pancreatic diseases may provide valuable new insights into treatment strategies. In this review, we first summarize the hallmark features of ferroptosis and then analyze the exact mechanisms by which ferroptosis is precisely regulated at multiple levels and links, including iron metabolism, lipid metabolism, the GPX4-mediated ferroptosis defense system, the GPX4-independent ferroptosis defense system, and the regulation of autophagy on ferroptosis. Finally, we discuss the role of ferroptosis in the occurrence and development of pancreatic diseases and summarize the feasibility and limitations of ferroptosis as a therapeutic target for pancreatic diseases.

Identifying endotypes of individuals after an attack of pancreatitis based on unsupervised machine learning of multiplex cytokine profiles

After an attack of pancreatitis, individuals may develop metabolic sequelae (eg, new-onset diabetes) and/or pancreatic cancer. These new-onset morbidities are, at least in part, driven by low-grade inflammation. The aim was to study the profiles of cytokines/chemokines in individuals after an attack of pancreatitis. A commercially available panel including 31 cytokines/chemokines was investigated. Random forest classifier and unsupervised hierarchical clustering were applied to study participants (who had no persistent organ failure and did not require ICU admission) according to their cytokine/chemokine profiles. Pancreatitis-related characteristics, detailed body composition (determined using 3.0 T magnetic resonance imaging), markers of glucose, lipid, and iron metabolism, gut and pancreatic hormones, as well as liver and pancreatic enzymes, were compared between clusters. Bootstrap validation was employed. A total of 160 participants, including 107 postpancreatitis individuals (investigated at a median of 18 months after the last attack of pancreatitis) and 53 healthy volunteers, were studied. Twenty-two cytokines/chemokines were significantly different between postpancreatitis and health. Two distinct endotypes of individuals after an attack of pancreatitis were identified-‟inflammatory" and ‟noninflammatory." Sixteen cytokines/chemokines were significantly higher in the inflammatory endotype compared with the noninflammatory endotype. No cytokine/chemokine was significantly higher in the noninflammatory endotype. The inflammatory endotype was characterized by significantly elevated insulin (P= 0.001), glucose-dependent insulinotropic peptide (P = 0.001), peptide YY (P = 0.017), and ghrelin (P = 0.014). The noninflammatory endotype was characterized by significantly elevated hepcidin (P= 0.016). Pancreatitis-related factors, body composition, and other studied parameters did not differ significantly between the 2 endotypes. Individuals with a similar phenotype and clinical course of pancreatitis have differing cytokine/chemokine profiles after clinical resolution of the disease. People with the inflammatory endotype have distinct changes in the pancreatic and gut hormones known to be involved in the pathogenesis of new-onset morbidities after an attack of pancreatitis.

Associations Between Iron Homeostasis and Pancreatic Enzymes After an Attack of Pancreatitis

OBJECTIVES

Dysregulation of iron homeostasis and exocrine pancreatic dysfunction are linked but remain undefined in individuals with a history of pancreatitis. The objective is to investigate the relationship between iron homeostasis and pancreatic enzymes in individuals after a pancreatitis attack.

METHODS

This was a cross-sectional study of adults with a history of pancreatitis. Markers of iron metabolism (hepcidin and ferritin) and pancreatic enzymes (pancreatic amylase, pancreatic lipase, and chymotrypsin) were measured in venous blood. Habitual dietary iron intake data (total, heme, and nonheme iron) were collected. Multivariable linear regression analyses were performed while considering covariates.

RESULTS

One hundred and one participants were studied at a median of 18 months after their last pancreatitis attack. Hepcidin was significantly associated with pancreatic amylase (β coefficient, -6.68; 95% confidence interval, -12.88 to -0.48; P = 0.035) and heme iron intake (β coefficient, 0.34; 95% confidence interval, 0.08 to 0.60; P = 0.012) in the adjusted model. Hepcidin was not significantly associated with pancreatic lipase or chymotrypsin. Ferritin was not significantly associated with pancreatic enzymes and dietary iron intake.

CONCLUSIONS

An iron homeostasis-exocrine pancreas crosstalk exists in individuals after an attack of pancreatitis. The role of iron homeostasis in pancreatitis warrants high-quality purposely-designed studies.

Ferroptosis and its emerging roles in acute pancreatitis

ABSTRACT

Acute pancreatitis (AP) is a common and potentially life-threatening pancreatic inflammatory disease. Although it is usually self-limiting, up to 20% of patients will develop into severe AP. It may lead to systemic inflammatory response syndrome and multiple organ dysfunction, affecting the lungs, kidneys, liver, heart, etc. Surviving patients usually have sequelae of varying degrees, such as chronic hyperglycemia after AP (CHAP), pancreatic exocrine insufficiency, and chronic pancreatitis. Lacking specific target treatments is the main reason for high mortality and morbidity, which means that more research on the pathogenesis of AP is needed. Ferroptosis is a newly discovered regulated cell death (RCD), originally described in cancer cells, involving the accumulation of iron and the depletion of plasma membrane polyunsaturated fatty acids, and a caspase-independent RCD. It is closely related to neurological diseases, myocardial infarction, ischemia/reperfusion injury, cancer, etc. Research in the past years has also found the effects of ferroptosis in AP, pancreatic cancer, and AP complications, such as acute lung injury and acute kidney injury. This article reviews the research progress of ferroptosis and its association with the pathophysiological mechanisms of AP, trying to provide new insight into the pathogenesis and treatment of AP, facilitating the development of better-targeted drugs.

Associations of Habitual Mineral Intake with New-Onset Prediabetes/Diabetes after Acute Pancreatitis

Associations between habitual dietary intake of minerals and glucose metabolism have been extensively studied in relation to metabolic disorders. However, similar research has yet to be conducted in individuals after acute pancreatitis (AP). The main aim was to investigate the associations between habitual intake of 13 minerals and glycaemic status: new-onset prediabetes/diabetes after AP (NODAP), pre-existing prediabetes/type 2 diabetes (T2DM), and normoglycaemia after AP (NAP). Associations between the dietary intake of minerals and markers of glucose metabolism (glycated haemoglobin and fasting plasma glucose) were also studied. The EPIC-Norfolk food frequency questionnaire was used in a cross-sectional fashion to determine the habitual intake of 13 dietary minerals. ANCOVA as well as multiple linear regression analyses were conducted and five statistical models were built to adjust for covariates. The study included 106 individuals after AP. In the NODAP group, intake of 4 minerals was significantly less when compared with the NAP group: iron (B = -0.076, p = 0.013), nitrogen (B = -0.066, p = 0.003), phosphorous (B = -0.046, p = 0.006), and zinc (B = -0.078, p = 0.001). Glycated haemoglobin was significantly associated with iodine intake (B = 17.763, p = 0.032) and manganese intake (B = -17.147, p = 0.003) in the NODAP group. Fasting plasma glucose was significantly associated with manganese intake (B = -2.436, p = 0.027) in the NODAP group. Habitual intake of minerals differs between individuals with NODAP, T2DM, and NAP. Prospective longitudinal studies and randomised controlled trials are now warranted to further investigate the associations between mineral intake and NODAP.

Relationship between Energy Balance and Circulating Levels of Hepcidin and Ferritin in the Fasted and Postprandial States

Markers of iron metabolism are altered in new-onset diabetes, but their relationship with metabolic signals involved in the maintenance of energy balance is poorly understood. The primary aim was to explore the associations between markers of iron metabolism (hepcidin and ferritin) and markers of energy balance (leptin, ghrelin, and the leptin/ghrelin ratio) in both the fasted and postprandial states. These associations were also studied in the sub-groups stratified by diabetes status. This was a cross-sectional study of individuals without disorders of iron metabolism who were investigated after an overnight fast and, in addition, some of these individuals underwent a mixed meal test to determine postprandial responses of metabolic signals. The associations between hepcidin, ferritin, and leptin, ghrelin, leptin/ghrelin ratio were studied using several multiple linear regression models. A total of 76 individuals in the fasted state and 34 individuals in the postprandial state were included. In the overall cohort, hepcidin was significantly inversely associated with leptin (in the most adjusted model, the β coefficient ± SE was -883.45 ± 400.94; p = 0.031) and the leptin/ghrelin ratio (in the most adjusted model, the β coefficient ± SE was -148.26 ± 61.20; p = 0.018) in the fasted state. The same associations were not statistically significant in the postprandial state. In individuals with new-onset prediabetes or diabetes (but not in those with normoglycaemia or longstanding prediabetes or diabetes), hepcidin was significantly inversely associated with leptin (in the most adjusted model, the β coefficient ± SE was -806.09 ± 395.44; p = 0.050) and the leptin/ghrelin ratio (in the most adjusted model, the β coefficient ± SE was -129.40 ± 59.14; p = 0.037). Leptin appears to be a mediator in the link between iron metabolism and new-onset diabetes mellitus. These findings add to the growing understanding of mechanisms underlying the derangements of glucose metabolism.

Effect of β-hydroxybutyrate monoester on markers of iron metabolism in new-onset prediabetes: findings from a randomised placebo-controlled trial

Background: People with prediabetes often have altered iron metabolism and may benefit from mild exogenous ketosis, which can now be successfully achieved thanks to recent developments in chemistry of food components. Objective: The objective was to investigate the effect of acute exogenous ketone monoester (β-hydroxybutyrate) on plasma levels of markers of iron metabolism in people with prediabetes. Methods: Eighteen participants with new-onset prediabetes after acute pancreatitis aged 18 years or above took part in randomised controlled cross-over trial in Auckland, New Zealand. After an overnight fast, participants consumed the exogenous ketone supplement or placebo. Blood samples were collected in the fasted state (0 minutes) and then serially every 30 minutes for 150 minutes. Both participants and study personnel were blinded to the intervention/placebo allocation. Repeated measures analysis of variance was performed using total area under the curve to determine the change in hepcidin and ferritin over time after consumption of the exogenous ketone supplement and placebo. Results: Consumption of the exogenous ketone supplement significantly elevated blood levels of β-hydroxybutyrate from 0.20 mmol L^-1 at baseline to 3.50 mmol L^-1 at 30 minutes (p < 0.05) and remained significantly elevated for the duration of the trial. The total area under the curve of hepcidin was 340.5 ± 121.1 ng mL^-1 after the exogenous ketone supplementation as compared with 343.2 ± 119.6 ng mL^-1 min^-1 after the use of placebo (p = 0.91). The total area under the curve of ferritin was 786.7 ± 129.1 ng mL^-1 min^-1 after the exogenous ketone supplementation as compared with 776.9 ± 131.4 ng mL^-1 min^-1 after the use of placebo (p = 0.10). Conclusion: Acute supplementation of β-hydroxybutyrate did not significantly affect the circulating levels of hepcidin or ferritin in people with prediabetes. Long-term effects of β-hydroxybutyrate warrant investigations in the future.

Wedelolactone alleviates acute pancreatitis and associated lung injury via GPX4 mediated suppression of pyroptosis and ferroptosis

Acute pancreatitis (AP) is an inflammatory disorder associated with multiple organ failure. Pyroptosis and ferroptosis are two newly recognized cell death, and whether pyroptosis and ferroptosis are involved in AP remain largely elusive. The nature compound Wedelolactone (Wed) exhibits strong anti-inflammatory and antioxidant activities, the present study aims to investigate the effect of Wed on AP and unravel whether Wed could protect against AP and relevant lung injury against pyroptosis and ferroptosis. Our results showed that the pyroptosis inhibitor disulfiram or ferroptosis inhibitor ferrostatin-1 significantly alleviated AP and associated lung injury in the taurocholate or caerulein-induced murine AP model. Administration with Wed ameliorated AP and lung injury as evidenced by improved pathological injuries, reduced serum pancreatic digestive enzymes, and proinflammatory cytokines. The in vivo and in vitro data demonstrated that Wed broadly inhibited caspase1/caspase11 activation, reduced mature interleukin-1β (IL-1β) and N-terminal domain of gasdermin D (GSDMD-N) level. The oxidative stress and lipid peroxidation were also suppressed along with the up-regulation of the ferroptosis antagonism marker glutathione peroxidase-4 (GPX4) in Wed treatment group. Wed promoted the transcriptional activity and the selenium sensitivity of GPX4. Moreover, the protective effects of Wed in caerulein-stimulated pancreatic acinar cells were markedly abrogated by the down-regulation of GPX4. Collectively, our data suggest that pyroptosis and ferroptosis play crucial roles in AP. Wed mitigated AP and associated lung injury via GPX4 mediated suppression of pyroptosis and ferroptosis.

Association between Habitual Dietary Iron Intake and Glucose Metabolism in Individuals after Acute Pancreatitis

Dietary intake of iron is known to be associated with impaired glucose metabolism. However, its involvement in derangements of glucose metabolism after acute pancreatitis (AP) is not completely understood. The aim was to investigate the association between dietary iron intake and markers of glucose metabolism in individuals after an attack of AP. Fasting blood samples were collected to analyse markers of glucose metabolism (fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c)). The EPIC-Norfolk food frequency questionnaire was used to determine the habitual intake of dietary iron (total, haem, and non-haem). Multivariable linear regression analyses were conducted and six statistical models were built to adjust for covariates. A total of 109 individuals after AP were studied in a cross-sectional fashion. Total iron (β (95% confidence interval) = -0.19 (-0.35, -0.05); p = 0.01 in the most adjusted model) and non-haem iron (β (95% confidence interval) = -0.19 (-0.33, -0.04); p = 0.03 in the most adjusted model) were significantly associated with FPG, consistently in all adjusted model. Total iron and non-haem iron did not have consistent significant associations with HbA1c. Dietary haem iron intake was not associated with either FPG or HbA1c. Habitual intake of dietary iron is inversely associated with FPG in individuals after an attack of AP and may be involved in the pathogenesis of new-onset diabetes after pancreatitis. Prospective longitudinal studies are now warranted to unveil the specific mechanism underlying the involvement of dietary iron.

Dalteparin as a Novel Therapeutic Agent to Prevent Diabetic Encephalopathy by Targeting Oxidative Stress and Inflammation

Introduction:

Hepcidin is the main modulator of systemic iron metabolism, and its role in the brain has been clarified recently. Studies have shown that hepcidin plays an important role in neuronal iron load and inflammation. This issue is of significance because neuronal iron load and inflammation are pathophysiological processes that are highly linked to neurodegeneration. Moreover, the activity of hepcidin has recently been manipulated to recover the neuronal impairment caused by brain inflammation in animal models.

Methods:

Streptozotocin (STZ) was used to induce type 1 diabetes. Male Wistar rats (n = 40) with a weight range of 200–250 g were divided into control, diabetic, diabetic + insulin, and diabetic + dalteparin groups. Dalteparin (100 mg/kg IP) and insulin (100 mg/kg SC) were administered for 8 weeks. At the end of the experiment, Y-maze and passive avoidance tasks were carried out. The animals were perfused randomly and their hippocampal tissue was isolated for the analysis of markers such as lipid peroxidation like Malondialdehyde (MDA), hepcidin expression, iron, and ferritin. Blood samples were taken for the measurement of serum inflammatory cytokine Interleukin (IL)-6.

Results:

The findings indicated that treatment with dalteparin reduced IL-6, MDA, ferritin, and hepcidin expression in diabetic rats compared to treatment with insulin (P<0.05). Moreover, treatment with dalteparin did not decrease the iron level or prevented its decline.

Conclusion:

Treatment with dalteparin improved the cognitive dysfunctions and symptoms of Alzheimer disease in STZ-induced diabetic rats by appropriately modulating and reducing oxidative stress and neuroinflammation. This may enhance the existing knowledge of therapeutics to reduce cognitive impairment in diabetes and is suggested to be a potential therapeutic agent in diabetes.

Iron metabolism and the exocrine pancreas

Although the pathophysiological mechanisms and consequences of gross derangements in iron metabolism are well known, little is known about the pathophysiological mechanisms underlying mild-to-moderate alterations in iron metabolism and their consequences. Growing evidence indicates that the exocrine pancreas has a bidirectional relationship with iron metabolism. Studies have shown alterations in circulating markers of iron metabolism, iron absorption, and intra-pancreatic iron deposition in pancreatitis. At the same time, exocrine pancreatic dysfunction has been shown in iron overload disorders. These observations reveal a compelling connection between the exocrine pancreas and iron metabolism, which are further elucidated by observations of therapeutic benefits of iron chelating agents and pancreatic enzyme replacement therapy. While the pancreas is not a major reservoir of iron in the body, better understanding of its relationship with iron metabolism may yield unexpected insights.

Panorama of mediators in postpancreatitis diabetes mellitus

PURPOSE OF REVIEW

To provide an overview of mediators involved in the pathogenesis of postacute pancreatitis diabetes mellitus.

RECENT FINDINGS

The 'holistic prevention of pancreatitis' framework has brought to the fore the sequelae of not only end-stage chronic pancreatitis and extensive pancreatic necrosis but also mild acute pancreatitis. Insights from the DORADO project have provided a wealth of information on the signalling molecules that do and do not affect glucose metabolism in individuals after mild acute pancreatitis and have challenged conventional views of the pathogenesis of postpancreatitis diabetes mellitus.

SUMMARY

Growing evidence compels a reconsideration of the dogma that mechanical β-cell destruction (and the resulting insulin deficiency) is the only underlying mechanism of postpancreatitis diabetes mellitus. Chronic low-grade inflammation, β-cell compensation, lipolysis, altered secretion of gut hormones, and changes in iron metabolism characterize postacute pancreatitis diabetes mellitus. Some of these are druggable targets that offer novel opportunities to reduce the burden of pancreatitis through tertiary prevention.

Antidiabetic Medications and Mortality Risk in Individuals With Pancreatic Cancer-Related Diabetes and Postpancreatitis Diabetes: A Nationwide Cohort Study

OBJECTIVE

There are no specific treatment guidelines for diabetes of the exocrine pancreas. High-quality studies are warranted to investigate whether the use of antidiabetic medications has survival benefit in individuals with diabetes of the exocrine pancreas. The objective was to determine the risk of mortality associated with the use of antidiabetic medications in individuals with pancreatic cancer-related diabetes (PCRD) and postpancreatitis diabetes mellitus (PPDM).

RESEARCH DESIGN AND METHODS

Nationwide pharmaceutical dispensing data (2006-2015) linked to hospital discharge data were used to identify 1,862 individuals with PCRD or PPDM. Multivariable Cox regression analysis was conducted, and the risk was expressed as hazard ratios and 95% CIs. A 6-month lag was used to minimize reverse causality.

RESULTS

In individuals with PCRD, ever users of metformin (adjusted hazard ratio 0.54; 95% CI 0.46-0.63) and ever users of insulin (adjusted hazard ratio 0.46; 95% CI 0.39-0.55) had significantly lower risks of mortality compared with never users of antidiabetic medications. These associations attenuated toward the null with the use of a 6-month lag. In individuals with PPDM, ever users of metformin had a significantly lower risk of mortality (adjusted hazard ratio 0.51; 95% CI 0.36-0.70), whereas ever-users of insulin did not have a significantly changed risk of mortality (adjusted hazard ratio 0.75; 95% CI 0.49-1.14) compared with never users of antidiabetic medications. The former association remained significant with the use of a 6-month lag.

CONCLUSIONS

Metformin promotes a survival benefit in individuals with PPDM but not PCRD. Reverse causality may play a role in the association between insulin use and mortality in PCRD.

Pro-inflammatory cytokine-induced lipolysis after an episode of acute pancreatitis

CONTEXT

Pro-inflammatory cytokine-stimulated lipolysis is one of the mechanisms underlying the pathogenesis of type 2 diabetes. However, whether it plays a role in the pathogenesis of post-pancreatitis diabetes mellitus (PPDM) remains unknown.

OBJECTIVE

To investigate the associations between markers of lipid metabolism and pro-inflammatory cytokines in individuals after acute pancreatitis (AP) in general, and in individuals with abnormal glucose metabolism (AGM) following AP in particular.

METHODS

Fasting blood samples were collected to measure markers of lipid metabolism (apolipoprotein-B, cholesterol, free fatty acids (FFA), glycerol, high and low-density lipoproteins, triglycerides) and cytokines (interleukin (IL)-6, monocyte chemoattractant protein (MCP)-1, and tumour necrosis factor (TNF) α). Linear regression analysis was conducted. Four statistical models were used to adjust for patient- and pancreatitis-related characteristics.

RESULTS

A total of 83 patients were recruited. IL-6 was significantly associated with glycerol in all models (p < .05), with glycerol levels increasing by 106% in individuals with AGM after AP (p <.05) compared to a 30.3% increase in individuals with normal glucose metabolism (NGM) (p >.05). TNFα was significantly associated with FFA (p = .015) in individuals with AGM after AP in the most adjusted model, with FFA levels increasing by 314% in these individuals compared to a 162% decrease in individuals with NGM after AP (p >.05).

CONCLUSIONS

Lipolysis appears to be an important pathogenetic mechanism in glucose derangements after diseases of the exocrine pancreas. IL-6 and TNFα are the driving forces behind lipolysis in individuals with AGM after AP. Modulation of lipolysis may be a promising therapeutic modality.

Profile of Gut Hormones, Pancreatic Hormones and Pro-inflammatory Cytokines in New Zealand Maori

Background

Maori, indigenous people of New Zealand, have at least two times higher prevalence of obesity and diabetes in comparison with the general population in the country. Gut and pancreatic hormone profile differences as well as pro-inflammatory milieu may contribute to this disparity. The aim was to investigate the differences in gut hormones, pancreatic hormones and pro-inflammatory cytokines between Maori and non-Maori individuals.

Methods

This was a cross-sectional study. Fasting blood samples were collected to measure cholecystokinin, ghrelin, gastric inhibitory peptide, glicentin, glucagon-like peptide-1 and -2, oxyntomodulin, secretin, amylin, C-peptide, glucagon, insulin, pancreatic polypeptide, somatostatin, interleukin-6, monocyte chemoattractant protein-1 and tumour necrosis factor-α. Binary logistic regression analysis was conducted in one unadjusted and four adjusted statistical models adjusting for patient-, metabolic- and pancreatitis-related factors.

Results

A total of 8 Maori and 85 non-Maori individuals were included. Circulating levels of ghrelin, pancreatic polypeptide and interleukin-6 levels were significantly higher in Maori (P = 0.005, P = 0.003 and P = 0.011, respectively) in both unadjusted and all the four adjusted analyses. Other signaling molecules did not show consistently significant associations with ethnicity.

Conclusion

Profile of gut hormones, pancreatic hormones and pro-inflammatory cytokines appears to differ between Maori and non-Maori individuals, independent of obesity, diabetes and other covariates. This may go some way to explain the increased propensity to obesity and diabetes in the Maori population.

Interplay between innate immunity and iron metabolism after acute pancreatitis

Emerging evidence shows that chronic low-grade inflammation and changes in markers of innate immunity are implicated in a range of metabolic abnormalities following an episode of acute pancreatitis. Also, deranged iron metabolism has been linked to type 2 diabetes mellitus, gestational diabetes, and new-onset diabetes after pancreatitis - the conditions characterized by high haemoglobin glycation index (HGI). This study aimed to investigate the associations between markers of innate immunity and iron metabolism in individuals after acute pancreatitis. Fasting blood samples were collected to analyse lipopolysaccharide binding protein (LBP), interleukin (IL)-6, tumor necrosis factor-α, hepcidin, ferritin, soluble transferrin receptor, HbA1c, and glucose. Participants were categorized into two groups: low HGI and high HGI. Linear regression analyses were conducted, and potential confounders (age, sex, ethnicity, body mass index, diabetes mellitus status, smoking status, aetiology of pancreatitis, duration, recurrence, and severity of pancreatitis) were adjusted for in 5 statistical models. A total of 93 patients following an episode of acute pancreatitis were included, of who 40 (43%) had high HGI. In the overall cohort, LBP was significantly associated with hepcidin and ferritin, and IL-6 was significantly associated with hepcidin, consistently in all the models. Further, LBP contributed to 7.7% and 9.5% of variance in hepcidin and ferritin levels, respectively, whereas IL-6 contributed to 5.3% of hepcidin variance. Upon subgroup analysis, the observed LBP associations were maintained in the high HGI subgroup only and the IL-6 association in the low HGI subgroup only. No consistently significant associations were found between any of the other markers. The interplay between LBP, IL-6, hepcidin, and ferritin characterizes metabolic derangements after acute pancreatitis and may play a role in the pathogenesis of new-onset diabetes after pancreatitis.