Development and characterization of two novel 68 Ga-labelled neuropeptide Y short analogues with potential application in breast cancer imaging.

In vivo receptor targeting with radiolabelled peptide-based probes is an attractive approach for the development of novel radiotracers for molecular imaging. This work presents the development and characterization of two novel neuropeptide Y analogues labelled with a positron emitter 68 Ga, for potential use in breast cancer imaging. Both analogues share the same amino acid sequence and were derivatized with NOTA through either a lysine linker (L1) or an acetylated lysine (L2). In both cases, a single product with radiochemical purity higher than 95% was obtained. The two complexes were hydrophilic, showed remarkable in vitro stability, good cellular uptake, binding affinity in the nanomolar range and high cellular internalization rate. Biodistribution studies revealed low blood uptake and elimination through the urinary tract. The addition of an acetyl group in the spacer increased the lipophilicity of C2 and modified the reactivity of the ε-amino group of the lysine which resulted in lower protein binding and lower percentage of injected dose in bladder and urine. The tumour versus muscle ratio was (3.8 ± 0.4) for 68 Ga-L1 and (4.7 ± 0.4) for 68 Ga-L2. These results encourage performing further studies in order to complete the evaluation of both tracers as potential radiopharmaceutical for breast cancer imaging.

Modulation of neuropeptide Y levels is impaired in crack withdrawal patients

Abstract Introduction The dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has a key role in drug addiction susceptibility. In addition to the well-known relationship between cortisol and the HPA axis, other molecules are involved with stress response and could modify the HPA activation, such as the neuropeptide Y (NPY), which has anxiolytic proprieties. There are few studies evaluating the effect of NPY levels on addiction, especially in crack cocaine dependence. Objective To evaluate NPY in crack users during early withdrawal to determine its relationship with drug use and cortisol levels. Methods We analyzed 25 male inpatient crack users. Serum NPY levels were measured at admission and discharge (mean of 24 days). Morning salivary cortisol was measured at admission. Results Serum NPY levels at admission and discharge were very similar. Lower NPY levels at discharge were associated with higher lifetime crack use. Also, a negative correlation was found between morning cortisol and delta NPY (NPY discharge - NPY admission). Conclusion These preliminary findings indicate that crack use influences the modulation of NPY levels and modifies stress response. The NPY pathway may play an important role in the pathophysiology of crack addiction, and the anxiolytic effect of NPY may be impaired in crack users. Future studies should consider NPY as a measurable indicator of the biological state in addiction.

Serum Neuropeptide Y Levels Are Associated with TNF-α Levels and Disease Activity in Rheumatoid Arthritis.

BACKGROUND: Neuropeptide Y (NPY) is a sympathetic neurotransmitter with effects on the regulation of inflammatory cells. The role of NPY on autoimmune inflammatory diseases such as rheumatoid arthritis (RA) is not completely understood. Therefore, we evaluate if NPY levels are markers of disease activity in RA and if there is a correlation between NPY levels and tumor necrosis factor-alpha (TNF-α), leptin, and interleukin 6 (IL-6) levels. METHODS: Cross-sectional design, including 108 women with RA. We assessed disease activity by DAS28-ESR (considering active disease a score of ≥2.6). Serum NPY levels and anti-CCP2 antibody, TNF-α, IL-6, and leptin levels were quantified (ELISA). RESULTS: Sixty-eight RA had an active disease (RA-active), and 40 were in remission (RA-remission). RA-active patients had higher NPY levels vs. RA-remission (22.8 ± 13.6 vs. 17.8 ± 10.3; p = 0.04). NPY levels correlated with increased TNF-α levels (r = 0.32, p = 0.001). Leptin or IL-6 did not correlate with NPY levels. In the logistic regression analysis, NPY increased the risk of disease activity (OR: 1.04, 95% CI 1.006-1.09, and p = 0.03). CONCLUSION: Higher NPY levels are an independent marker of disease activity in RA. This study encourages the quantification of NPY levels as a surrogate marker for RA-active. Future studies evaluating the role of NPY levels interacting with other proinflammatory cytokines are required.

The effects of IVIg therapy on serum levels of neuropeptide Y and cytokines in Guillain-Barré syndrome.

BACKGROUND: Guillain-Barré syndrome (GBS) is a common acute immune-mediated inflammatory disorder affecting the peripheral nervous system (PNS) of humans. Studies in humans and in animal models revealed that neuropeptide Y (NPY) levels are altered in some neurodegenerative and neuroimmune disorders. Herein, we investigated the levels of NPY and cytokines in the serum of GBS patients and explored the roles of NPY in the disease severity and its short-term prognosis. METHODS: Twenty patients with GBS (case group) and twenty healthy individuals (control group) were enrolled in this study. NPY levels were analyzed by enzyme-linked immunosorbent assay (ELISA). The levels of pro- and anti-inflammatory cytokines (including interferon-γ (IFN-γ), interleukin (IL)-4, IL-10, IL-12p70, IL-17A, and tumor necrosis factor-α (TNF-α)) were analyzed using cytometric beads array (CBA). The clinical characteristics, disease severity, and short-term prognosis were compared between the two groups. RESULTS: Compared with the control group, the levels of NPY and cytokines were significantly increased in the serum of patients with GBS. NPY levels in the serum of GBS patients were correlated with the disease severity. CONCLUSION: Our results suggest that NPY and cytokines are involved in the pathogenesis of GBS. The levels of NPY can help to predict the severity of the disease.

Prognostic Value of Serum NPY Hypermethylation in Neoadjuvant Chemoradiotherapy for Rectal Cancer: Secondary Analysis of a Randomized Trial.

OBJECTIVES: Long-term prevention of metastatic disease remains a challenge in locally advanced rectal cancer, and robust pretreatment prognostic factors for metastatic progression are lacking. We hypothesized that detecting circulating tumor-specific DNA (ctDNA) based on hypermethylation of the neuropeptide Y gene (meth-ctDNA) could be a prognostic marker in the neoadjuvant setting; we examined this in a secondary, explorative analysis of a prospective trial. MATERIALS AND METHODS: Serum samples were prospectively collected in a phase III trial for locally advanced rectal cancer. Positivity for and fractional abundance of meth-ctDNA in baseline samples were estimated. Overall survival (OS) and the rate of distant metastases were compared between meth-ctDNA positive and negative patients; other prognostic factors were controlled for in multivariate Cox regression. Importance of quantitative load was examined by considering the fractional abundance of meth-ctDNA relative to total circulating DNA. RESULTS: Baseline serum samples were available for 146 patients. In total, 30 patients had presence of meth-ctDNA, with no correlation with cT (P=0.8) or cN (P=0.6) stages. Median follow-up was 10.6 years for OS and 5.1 years for freedom from distant metastases. Patients with meth-ctDNA had significantly worse 5-year OS (47% vs. 69%), even when controlling for other prognostic factors (hazard ratio=2.08; 95% confidence interval, 1.23-1.51). This seemed mainly driven by disparity in the rate of distant metastases (55% vs. 72% at 5 y, P=0.01); hazard ratio=2.20 (95% confidence interval, 1.19-4.07, P=0.01) in multivariate analysis. Increased quantitative load was highly significant for worse outcomes. CONCLUSIONS: Meth-ctDNA could be a potential prognostic marker in the neoadjuvant setting and may, if validated, identify patients at increased risk of distant metastases.

Neuropeptide Y and dipeptidyl peptidase IV in normally cycling and postmenopausal women: A prospective pilot study.

The purpose was to investigate changes in neuropeptide Y (NPY) protein and dipeptidyl peptidase IV (DPP-IV) activity in the plasma and saliva in normally cycling women and women after menopause. We recruited 7 cycling women and 7 postmenopausal women for a cross-sectional, prospective pilot study. Blood via venipuncture and saliva samples were taken at each point in the menstrual cycle (premenopausal) or once per week (postmenopausal) for 2 months. Blood and saliva were analyzed for estrogen, NPY using ELISA and DPP-IV activity using a fluorometric assay. Plasma ß-estradiol was an average of 96.45 ±â€Š57.04 pg/mL over 2 cycles in the premenopausal group and 1.72 ±â€Š0.35 pg/mL over 2 months in the postmenopausal group (P < .05). In the cycling group, there were no significant differences in saliva or plasma NPY or DPP-IV over the cycle. For the postmenopausal group, salivary NPY and DPP-IV did not change over 2 months. Plasma NPY was lowest in the middle 2 weeks (average: 0.52 ±â€Š0.10 ng/mL) compared to the first and fourth weeks (average of week 1 and 4: 0.60 ±â€Š0.14 ng/mL; P < .05). Plasma NPY in postmenopausal women was higher overall (0.56 ±â€Š0.13 ng/mL) compared to cycling women (0.30 ±â€Š0.11 ng/mL; P < .05). Plasma DPP-IV activity was unchanged by time in the postmenopausal group. Saliva DPP-IV and saliva NPY in the cycling group had a significant negative correlation (R = -0.95; P < .05). We found that saliva measures of NPY and DPP-IV activity appear to be poor estimates of plasma concentrations and activities, but a larger sample size is required to conform this. Differences in plasma NPY concentrations between the groups and the relationship between salivary NPY and DPP-IV suggests that there may be some unique differences between these groups.

Er Shen Wan extract reduces diarrhea and regulates AQP 4 and NHE 3 in a rat model of spleen-kidney Yang deficiency-induced diarrhea.

INTRODUCTION: Er Shen Wan (ESW), a traditional Chinese medicinal formula comprised of Psoraleae Fructus (Babchi seeds, from Psoralea corylifolia Linn.) and Myristicae Semen (Nutmeg, from Myristica fragrans Houtt.), is widely used to treat spleen-kidney Yang deficiency (SKYD)-induced diarrhea. Previous studies have demonstrated preliminarily that the petroleum ether extract of ESW (ESWP) exhibits significant anti-diarrheal activity. The present study aimed to evaluate the anti-diarrhea activity of ESWP and to explore the underlying mechanisms with respect to fluid metabolism in a rat model of SKYD-induced diarrhea. MATERIALS AND METHODS: A high-performance liquid chromatography-diode array detector (HPLC-DAD) approach was developed and validated for qualitative and quantitative analyses of the main constituents of ESWP. SKYD model rats were established and treated with an effective dose (3.5?g/kg) of the extract for two weeks. Anti-diarrheal activity and stool properties were observed. After the experiment, the appearance and histology of the intestines were evaluated. Serum levels of neuropeptide Y (NPY) and vasoactive intestinal peptide (VIP) were also determined. Furthermore, to characterize the regulation of aquaporin-4 (AQP 4) and Na+/H+ exchanger isoform 3 (NHE 3) in the colon, quantitative real-time RT-PCR (qRT-PCR), immunohistochemistry (IHC) and Western blotting (WB) were employed to detect mRNA and protein expression levels. RESULTS: In the rat models, oral ESWP administration significantly reduced the diarrhea score and the number and weight of wet stools. Jejunal and ileac histological damage was impeded, and the histology score decreased. Serum VIP levels were significantly decreased, in contrast to NPY levels. In addition, AQP 4 and NHE 3 expression levels increased significantly. CONCLUSIONS: These results showed that ESWP's anti-diarrheal effect might at least partially involve the regulation of hormones intimately involved in maintaining fluid and electrolyte levels, as well as by increasing AQP 4 and NHE 3 expression levels and enhancing the absorption of Na+ and water.

Effect of clozapine dose and concentration on fasting concentration of appetite regulating peptides.

The aim of this study is to analyze whether clozapine serum concentration may affect fasting serum levels of several appetite regulating peptides: CART, PYY(1-36), NPY, AgRP, des-acylated ghrelin, leptin and obestatin. Serum concentration of clozapine and fasting serum levels of des-acylated ghrelin, neuropeptide Y (NPY), agouti-related protein (AgRP), peptide YY (PYY(1-36)), cocaine- and amphetamine-regulated transcript (CART), leptin and obestatin were measured in 30 subjects with schizophrenia on clozapine monotherapy. Leptin concentration was negatively correlated with clozapine dose (r = -0.53, p = 0.002), while NPY concentration was negatively correlated with clozapine concentration (r = -0.55, p = 0.01). Correlations with other peptides were not significant. We cannot conclude that serum concentration of clozapine is directly associated with increased or decreased level of appetite-regulating peptides.

Plasma Neuropeptide Y Levels in Vasovagal Syncope in Children.

BACKGROUND: Vasovagal syncope (VVS) is the most common cause of syncope in children. Neuropeptide Y (NPY) plays an important role in the regulation of blood pressure (BP), as well as myocardial contractility. This study aimed to explore the role of plasma NPY in VVS in children. METHODS: Fifty-six children who were diagnosed with VVS (VVS group) using head-up tilt test (HUT) and 31 healthy children who were selected as controls (control group) were enrolled. Plasma NPY concentrations were detected. The independent t-test was used to compare the data of the VVS group with those of the control group. The changes in plasma NPY levels in the VVS group during the HUT, as well as hemodynamic parameters, such as heart rate (HR), BP, total peripheral vascular resistance (TPVR), and cardiac output (CO), were evaluated using the paired t-test. Furthermore, the correlations between plasma NPY levels and hemodynamic parameters were analyzed using bivariate correlation analysis. RESULTS: The BP, HR, and plasma NPY (0.34 ± 0.12 pg/ml vs. 0.46 ± 0.13 pg/ml) levels in the supine position were statistically low in the VVS group compared to levels in the control group (all P < 0.05). Plasma NPY levels were positively correlated with the HR (Pearson, R = 0.395, P < 0.001) and diastolic BP (Pearson, R = 0.311, P = 0.003) when patients were in the supine position. When patients in the VVS group were in the supine position, elevated TPVR (4.6 ± 3.7 mmHg·min-1·L-1 vs. 2.5 ± 1.0 mmHg·min-1·L-1, respectively, P < 0.001; 1 mmHg = 0.133 kPa) and reduced CO (1.0 ± 0.7 L/min vs. 2.4 ± 1.3 L/min, respectively, P < 0.001) were observed in the positive-response period compared with baseline values. The plasma NPY levels were positively correlated with TPVR (Spearman, R = 0.294, P = 0.028) but negatively correlated with CO in the positive-response period during HUT (Spearman, R = -0.318, P = 0.017). CONCLUSIONS: Plasma NPY may contribute to the pathogenesis of VVS by increasing the TPVR and decreasing the CO during orthostatic regulation.

Vulnerability to psychogenic non-epileptic seizures is linked to low neuropeptide Y levels.

Psychogenic non-epileptic seizures (PNES) is a conversion disorder that reflects underlying psychological distress. Female patients with PNES often present with a history of prolonged stressors, especially sexual abuse. In the current study, we studied the relationship between neuropeptide Y (NPY) and PNES symptoms in women with a history of sexual abuse. NPY has been associated with resilience to stress and we hypothesized that low levels would increase the extent and severity of PNES symptoms in this patient population. Serum levels of NPY, and related hormones were measured in fifteen female PNES patients and sixty female controls. PNES patients reported more severe abuse histories, feeling of abandonment, and decreased perception of quality of life than controls. Importantly, they also had lower NPY levels. Our analysis indicates that low levels of NPY in PNES may confer greater vulnerability to exhibit seizure-like symptoms and lower quality of life.

Role of sympathetic cotransmitter galanin on autonomic balance in heart failure: an active player or a bystander?

OBJECTIVE: Galanin, a cotransmitter similar to neuropeptide Y (NPY), aggravates autonomic imbalance in systolic heart failure (HF) by attenuating vagal tonus after burst sympathetic activity. In animal HF models, galanin antagonists have improved cardiac function. To determine whether galanin is a promising therapeutic target in HF, we studied its concentrations in HF patients and evaluated its correlation with NPY, markers of humoral activity such as pro-BNP and copeptin, and echocardiographic parameters of HF severity. METHODS: After recording demographic and echocardiographic characteristics of 87 individuals (57 HF patients and 30 control subjects), fasting serum concentrations of galanin, NPY, copeptin, and pro-BNP were determined. RESULTS: Unlike pro-BNP, copeptin, and NPY, which were significantly elevated in HF patients (p<0.001, p<0.001, and p=0.001, respectively), galanin was similar in HF patients and control subjects (p=0.9). NPY correlated with the echocardiographic parameters of HF severity (r=-0.22, p=0.03 for EF; r=0.3, p=0.005 for Tei index of RV; r=-0.23, p=0.03 for TAPSE; and r=0.24, p=0.024 for E/e') and pro-BNP (r=0.22, p=0.046). NPY levels were also associated with beta blocker (BB) use, wherein BB significantly decreased NPY in both HF patients and control subjects. Galanin correlated with humoral biomarkers, pro-BNP and copeptin (r=0.39, p<0.001 and r=0.41, p<0.001, respectively). Although current smoking, BB therapy, pro-BNP, copeptin, and body mass index were associated with galanin in univariate analyses, the multiple linear regression model revealed that pro-BNP was the only significant determinant of galanin levels in HF patients. CONCLUSION: Our findings confirmed the role of NPY in autonomic balance and suggest that galanin is associated with the proadrenergic state, but its role in HF in humans remains unclear.

Pain modulation in patients with fibromyalgia undergoing acupuncture treatment is associated with fluctuations in serum neuropeptide Y levels.

OBJECTIVES: Neuropeptide Y (NPY) is a neurotransmitter released by sympathetic neurons, which is probably involved in pain modulation. Acupuncture is increasingly used as an alternative or complementary means of controlling pain in rheumatic diseases such as fibromyalgia (FM), a chronic widespread pain syndrome accompanied by allodynia and hyperalgesia. The aim of the present study was to assess the effects of an acupuncture cycle on serum NPY levels in patients with FM, and identify possible correlations between its serum levels and clinical and clinimetric parameters. METHODS: The study involved 30 FM patients who underwent clinical and clinimetric evaluations and blood sampling at baseline and at the end of the treatment, and 20 healthy subjects who underwent blood sampling. RESULTS: The baseline serum NPY levels of the patients were higher than those of the controls. They had significantly increased by the end of the treatment, when there was also a statistically significant reduction in pain, the number of tender points number, and the clinimetric scores. CONCLUSIONS: These findings confirm the analgesic properties of acupuncture as a complementary treatment in FM, and indicate that NPY could play a role in pain modulation.

Increased high molecular weight adiponectin, but decreased total adiponectin and kisspeptin, in central precocious puberty compared with aged-matched prepubertal girls.

The aim of the present study was to compare serum leptin, kisspeptin, total adiponectin, high molecular weight (HMW) adiponectin and neuropeptide Y (NPY) levels between girls with central precocious puberty (CPP; n=26, 7-9.5 years old) and age-matched controls (n=29) including or excluding obese girls. Leptin and NPY levels were comparable between CPP and control girls. Kisspeptin levels were lower in the CPP than control group, and were positively correlated with oestrogen in the control group and with systolic and diastolic blood pressure in the CPP group. Kisspeptin levels were negatively correlated with FSH and LH in the CPP group. Total adiponectin levels were lower in CPP than control girls, and were negatively correlated with Tanner stage and body mass index, but positively correlated with the quantitative insulin sensitivity check index in the control group. HMW adiponectin was higher in the CPP than control group, and was positively correlated with Tanner stage and LH in all girls. Total adiponectin had a strong positive correlation with HMW adiponectin in the CPP group (r=0.915) compared with the control group (r=0.371). In conclusion, kisspeptin may be associated with increased oestrogen in prepubertal girls, but with increased blood pressure in girls with CPP. In girls entering puberty, HMW adiponectin was increased and associated with reproductive parameters. Based on these observations, HMW adiponectin probably plays an essential role in the initiation of puberty and is a candidate marker for the prediction of CPP.

Comparative Evaluation of Pain, Stress, Neuropeptide Y, ACTH, and Cortisol Levels Between a Conventional Postoperative Care Protocol and a Fast-Track Recovery Program in Patients Undergoing Major Abdominal Surgery.

BACKGROUND: Fast-track (FT) postoperative protocol in oncological patients after major abdominal surgery reduces complications and length of postoperative stay compared to the conventional (CON) protocol. However, stress and pain responses have not been compared between the two protocols. OBJECTIVES: To compare stress, pain, and related neuropeptidic responses (adrenocorticotropic hormone [ACTH], cortisol, and neuropeptide Y [NPY]) between FT and CON protocols. METHOD: A clinical trial with repeated measurements was conducted (May 2012 to May 2014) with a sample of 63 hepatectomized or pancreatectomized patients randomized into two groups: FT ( n = 29) or CON ( n = 34). Demographic and clinical data were collected, and pain (Visual Analog Scale [VAS] and Behavioral Pain Scale [BPS]) and stress responses (3 self-report questions) assessed. NPY, ACTH, and cortisol plasma levels were measured at T1 = day of admission, T2 = day of surgery, and T3 = prior to discharge. RESULTS: ACTHT1 and ACTHT2 levels were positively correlated with self-reported stress levels (ρ = .43 and ρ = .45, respectively, p < .05) in the FT group. NPY levels in the FT group were higher than those in the CON group at all time points ( p ≤ .004); this difference remained significant after adjusting for T1 levels through analysis of covariance for age, gender, and body mass index ( F = .003, F = .149, F = .015, respectively, p > .05). CONCLUSIONS: Neuropeptidic levels were higher in the FT group. Future research should evaluate this association further, as these biomarkers might serve as objective indicators of postoperative pain and stress.

Differences in Neuropeptide Y Secretion Between Intracerebral Hemorrhage and Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Neuropeptide Y (NPY) is one of the most potent endogenous vasoconstrictors, and its contribution to the multifactorial cascade of cerebral vasospasm due to nontraumatic subarachnoid hemorrhage (SAH) is not yet fully understood. This experimental study compared the hemorrhage-specific course of NPY secretion into cerebrospinal fluid (CSF) and into plasma between 2 groups: patients with SAH and patients with basal ganglia hemorrhage (BGH) or cerebellar hemorrhage (CH) over the first 10 days after hemorrhage. MATERIALS AND METHODS: Seventy-nine patients were prospectively included: SAH patients (n=66) (historic population) and intracerebral hemorrhage patients (n=13). All patients received an external ventricular drain within 24 hours of the onset of bleeding. CSF and plasma were drawn daily from day 1 to day 10. The levels of NPY were determined by means of competitive enzyme immunoassay. The CSF samples of 29 patients (historic population) who had undergone spinal anesthesia due to orthopedic surgery served as the control group. RESULTS: NPY levels in CSF were significantly higher in the 2 hemorrhage groups than in the control group. However, the 2 hemorrhage groups showed significant differences in NPY levels in CSF (SAH mean, 0.842 ng/mL vs. BGH/CH mean, 0.250 ng/mL; P<0.001) as well as in the course of NPY secretion into CSF over the 10-day period. NPY levels in plasma did not differ significantly among SAH, BGH/CH, and controls. CONCLUSIONS: Our findings support the hypothesis that excessive release of NPY into CSF but not into plasma is specific to aneurysmal SAH in the acute period of 10 days after hemorrhage. In BGH/CH, CSF levels of NPY were also increased, but the range was much lower.

Lower plasma levels of glucose-dependent insulinotropic peptide (GIP) and pancreatic polypeptide (PP) in patients with ductal adenocarcinoma of the pancreas and their relation to the presence of impaired glucoregulation and weight loss.

BACKGROUND: The changes in gastrointestinal hormones associated with pancreatic ductal adenocarcinoma (PDAC) in patients with impaired glucoregulation have yet to be evaluated. The aim of this study was to determine plasma concentrations of selected gastrointestinal hormones in PDAC patients with and without diabetes and to compare them with levels found in Type 2 diabetic patients without cancer. METHODS: In this study we examined plasma concentrations of glucose-dependent insulinotropic peptide (GIP), glucagon-like peptide 1 (GLP-1), pancreatic polypeptide (PP), peptide YY (PYY) and neuropeptide Y (NPY), and cytokines leptin and adiponectin in 94 patients with histologically confirmed PDAC. Thirty-nine patients with Type 2 diabetes without PDAC and 29 healthy individuals with no evidence of acute or chronic diseases were examined as controls. RESULTS: Significantly lower plasma concentrations of GIP were found in PDAC patients with new-onset diabetes/prediabetes (n = 76), or in those with normal glucose regulation (n = 18), compared to patients with Type 2 diabetes without PDAC and controls (15.5 (3.7-64.5) or 6.5 (1.7-24.5) vs. 39.8 (15.1-104.7) and 28.8 (7.4-112.2) ng/L, p < 0.001); the same relationship was observed for PP (38.9 (10.2-147.9) or 28.1 (7.9-100.0) vs 89.1 (38.0-208.9) and 75.8 (30.1-190.6) ng/L, p < 0.01), respectively. The lowest levels of GIP and PP concentrations were found in PDAC patients with new-onset diabetes/prediabetes and weight loss > 2 kg (p < 0.001). CONCLUSIONS: We conclude that GIP and PP plasma concentrations are lower in pancreatic cancer irrespective of the degree of glucose intolerance as compared to Type 2 diabetic patients and healthy controls. In new onset diabetes especially if associated with weight loss, these changes may represent a new clue for the diagnosis of PDAC.

Cross-talk between innate cytokines and the pancreatic polypeptide family in acute pancreatitis.

BACKGROUND AND AIM: Low-grade inflammation persists in patients with acute pancreatitis (AP) after hospital discharge, and is linked to metabolic disorders. Neuropeptide Y (NPY) is well recognized as an important mediator of inflammation in these patients but the role of the other two structurally similar peptides, pancreatic polypeptide (PP) and peptide YY (PYY), in inflammation has been sparsely investigated. The aim was to investigate the association between PYY, PP, NPY and circulating levels of innate cytokines in patients after AP. METHODS: Fasting blood samples were collected to measure PYY (ng/mL), PP (ng/mL), NPY (pg/mL), interleukin-6 (IL-6) (ng/mL), monocyte chemoattractant protein (MCP) 1 (ng/mL), and tumour necrosis factor (TNF) α (ng/mL). Modified Poisson regression analysis and linear regression analyses were conducted. Age, sex, ethnicity, obesity, diabetes, aetiology, time from 1st attack of AP, recurrence, severity, physical activity, and smoking were adjusted for in several statistical models. P<0.05 was considered statistically significant. RESULTS: A total of 93 patients were recruited. Peptide YY was significantly associated (p<0.001) with IL-6, MCP-1, and TNFα in the unadjusted and all adjusted models. Pancreatic polypeptide was significantly associated (p<0.001) with IL-6, MCP-1, and TNFα in the unadjusted and at least one adjusted model. Peptide YY and PP together contributed 22.2%, 72.7%, and 34.6% to the variance of IL-6, MCP-1, and TNFα, respectively. Neuropeptide Y was not significantly associated with any of the three cytokines. CONCLUSIONS: Peptide YY and PP are associated with circulating innate pro-inflammatory cytokines in patients after AP and cumulatively contribute to nearly half of the variance of IL-6, MCP-1, and TNFα. Future research is warranted to investigate the signaling pathways that underlie these associations.

Trimetazidine attenuates pressure overload-induced early cardiac energy dysfunction via regulation of neuropeptide Y system in a rat model of abdominal aortic constriction.

BACKGROUND: Metabolism remodeling has been recognized as an early event following cardiac pressure overload. However, its temporal association with ventricular hypertrophy has not been confirmed. Moreover, whether trimetazidine could favorably affect this process also needs to be determined. The aim of the study was to explore the temporal changes of myocardial metabolism remodeling following pressure-overload induced ventricular hypertrophy and the potential favorable effect of trimetazidine on myocardial metabolism remodeling. METHODS: A rat model of abdominal aortic constriction (AAC)-induced cardiac pressure overload was induced. These rats were grouped as the AAC (no treatment) or TMZ group according to whether oral trimetazidine (TMZ, 40 mg/kg/d, for 5 days) was administered. Changes in cardiac structures were sequentially evaluated via echocardiography. The myocardial ADP/ATP ratio was determined to reflect the metabolic status, and changes in serum neuropeptide Y systems were evaluated. RESULTS: Myocardial metabolic disorder was acutely induced as evidenced by an increased ADP/ATP ratio within 7 days of AAC before the morphological changes in the myocardium, accompanied by up-regulation of serum oxidative stress markers and expression of fetal genes related to hypertrophy. Moreover, the serum NPY and myocardial NPY-1R, 2R, and 5R levels were increased within the acute phase of AAC-induced cardiac pressure overload. Pretreatment with TMZ could partly attenuate myocardial energy metabolic homeostasis, decrease serum levels of oxidative stress markers, attenuate the induction of hypertrophy-related myocardial fetal genes, inhibit the up-regulation of serum NPY levels, and further increase the myocardial expression of NPY receptors. CONCLUSIONS: Cardiac metabolic remodeling is an early change in the myocardium before the presence of typical morphological ventricular remodeling following cardiac pressure overload, and pretreatment with TMZ may at least partly reverse the acute metabolic disturbance, perhaps via regulation of the NPY system.

Neuropeptide Y accelerates post-fracture bone healing by promoting osteogenesis of mesenchymal stem cells.

Fracture repair is a complex yet well orchestrated regenerative process involving numerous signaling and cell types including osteoblasts. Here we showed that NPY, a neurotransmitter with regulatory functions in bone homeostasis, may contribute to the post-fracture bone healing in patients with traumatic brain injury-fracture combined injuries. Our results suggested NPY levels were increased in patients with the combined injuries, accomplished by arising of bone healing markers, such as ALP, OC, PICP and ICTP, than in those with simple fractures, and NPY have direct actions on MSCs to promote their osteogenic differentiation. Our results provided clinical evidences for NPY participating in the bone healing process in a nonhypothalamic manner, most probably by directly promoting osteogenesis of mesenchymal stem cells.

Increased Dipeptidyl Peptidase-4 Activity Is Associated With High Prevalence of Depression in Middle-Aged and Older Adults: A Cross-Sectional Study.

OBJECTIVE: Obesity, inflammation, and decreased neuropeptide Y (NPY) are risk factors for depression. Dipeptidyl peptidase-4 (DPP4), a newly identified adipokine, has been proved to promote inflammation and NPY degradation. Hence, we aimed to investigate the association between plasma DPP4 activity and depression symptoms in middle-aged and older adults. METHODS: We cross-sectionally assessed 1,335 Chinese adults aged 45-76 years recruited from the Medical Examination Center, Guilin, China, between 2013 and 2014. The main outcome measures were plasma DPP4 activity, inflammatory markers, and NPY. Depression symptoms were determined by the score on the 9-item Patient Health Questionnaire (PHQ-9). Each of the 9 depression items of the PHQ-9 correspond to 1 of the DSM-IV diagnostic criteria for symptoms of major depressive disorder. RESULTS: Subjects in the highest quartile of DPP4 activity had higher body mass index (BMI), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP), and PHQ-9 score compared with subjects in the lowest quartile (P < .05). Compared to patients without depression symptoms, patients with depression symptoms had higher BMI, waist-to-hip ratio, IL-6, hs-CRP, and DPP4 activity (P < .05). DPP4 activity was associated positively with IL-6, hs-CRP, and PHQ-9 score and negatively with NPY after adjustment for potential confounders (P < .05). The risk for depression symptoms increased with higher levels of DPP4 activity and inflammation and lower levels of NPY. CONCLUSIONS: Increased DPP4 activity is independently associated with depression symptoms in middle-aged and older adults. The mechanisms might be partly explained by mutual influence among inflammation, NPY, and DPP4. These observations raise further interest in DPP4 activity for the potential effect on inflammation and NPY metabolism, as a risk biomarker, or even a possible therapeutic target for depression. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR-EPC-14005273).