Plasma neuropeptide Y immunoreactivity influences left ventricular mass in pheochromocytoma

Hypertension and cardiac damage in pheochromocytoma and paraganglioma patients: a large-scale single-center cohort study

BACKGROUND

Hypertension (HT) is one of the most common manifestations in patients with catecholamine-secreting neuroendocrine tumors. Although the cardiovascular manifestations of these tumors have been described, there have been no large-scale investigations of the profile of HT and changes in cardiac structure and function that occur in patients with pheochromocytomas and paragangliomas (PPGL).

MATERIALS AND METHODS

In this study, we investigated the prevalence of HT and left ventricular remodeling (LVR) in a cohort of 598 patients who underwent surgery for PPGL at our center between January 2001 and April 2022. Information on demographics, reason for hospitalization, medical history, biochemical parameters, findings on echocardiography, and tumor characteristics were recorded. The LVR index was compared according to whether or not there was a history of HT.

RESULTS

The average age was 47.07 ± 15.07 years, and 277 (46.32%) of the patients were male. A history of HT was found in 423 (70.74%) of the 598 patients. Paraganglioma was significantly more common in the group with HT (26.00% vs. 17.71%, P = 0.030) and significantly less likely to be found incidentally during a health check-up in this group (22.93% vs. 59.43%, P < 0.001). Among 365 patients with complete echocardiography data, left ventricular mass index (86.58 ± 26.70 vs. 75.80 ± 17.26, P < 0.001) and relative wall thickness (0.43 ± 0. 08 vs. 0.41 ± 0.06, P = 0.012) were significantly higher in patients with PPGL and a history of HT. The proportions with left ventricular hypertrophy (LVH) (19.40% vs. 8.25%, P = 0.011) and LVR (53.73% vs. 39.18%, P = 0.014) were also higher when there was a history of HT. After adjusting for age, gender, body mass index, alcohol consumption, smoking status, diabetes, stroke, creatinine level, tumor location, and tumor size, a history of HT was significantly correlated with LVH (odds ratio 2.71, 95% confidence interval 1.18-6.19; P = 0.018) and LVR (odds ratio 1.83, 95% confidence interval 1.11-3.03; P = 0.018).

CONCLUSION

HT is common in patients with PPGL (70.74% in this cohort). PPGL without a history of HT is more likely to be found incidentally (59.43% in our cohort). HT is associated with LVR in PPGL patients with complete echocardiography data. These patients should be observed carefully for cardiac damage, especially those with a history of HT.

Neuropeptide Y Peptide Family and Cancer: Antitumor Therapeutic Strategies

Currently available data on the involvement of neuropeptide Y (NPY), peptide YY (PYY), and pancreatic polypeptide (PP) and their receptors (YRs) in cancer are updated. The structure and dynamics of YRs and their intracellular signaling pathways are also studied. The roles played by these peptides in 22 different cancer types are reviewed (e.g., breast cancer, colorectal cancer, Ewing sarcoma, liver cancer, melanoma, neuroblastoma, pancreatic cancer, pheochromocytoma, and prostate cancer). YRs could be used as cancer diagnostic markers and therapeutic targets. A high Y1R expression has been correlated with lymph node metastasis, advanced stages, and perineural invasion; an increased Y5R expression with survival and tumor growth; and a high serum NPY level with relapse, metastasis, and poor survival. YRs mediate tumor cell proliferation, migration, invasion, metastasis, and angiogenesis; YR antagonists block the previous actions and promote the death of cancer cells. NPY favors tumor cell growth, migration, and metastasis and promotes angiogenesis in some tumors (e.g., breast cancer, colorectal cancer, neuroblastoma, pancreatic cancer), whereas in others it exerts an antitumor effect (e.g., cholangiocarcinoma, Ewing sarcoma, liver cancer). PYY or its fragments block tumor cell growth, migration, and invasion in breast, colorectal, esophageal, liver, pancreatic, and prostate cancer. Current data show the peptidergic system's high potential for cancer diagnosis, treatment, and support using Y2R/Y5R antagonists and NPY or PYY agonists as promising antitumor therapeutic strategies. Some important research lines to be developed in the future will also be suggested.

Hypertension and hypertensive cardiomyopathy in patients with a relapse-free history of phaeochromocytoma

BACKGROUND

In patients with a relapse-free history of phaeochromocytoma/paraganglioma (PCC/PGL), persistent hypertension has been reported, but has not been well characterized.

METHODS

In 28 patients [mean age 54·5 (26-81) years] with a relapse-free history of PCC/PGLs, we prospectively analysed resting, supine blood pressure (BP), ambulatory BP, echocardiography, exercise testing, metabolic parameters and retrospectively collected data from the time of diagnosis (baseline). Echocardiographic measures were compared to healthy (n = 28) and hypertensive controls (n = 15).

RESULTS

Median follow-up was 6 [1-16] years. Three patients had normal office and ambulatory BP and three patients had only increased office BP. Fifty-four per cent of patients had a blunted circadian rhythm. Comparing normal, hypertensive and PCC/PGL patients, we found significant differences in end-diastolic septal thickness (8·8 ± 0·2, 13·8 ± 0·4, 10·0 ± 0·3 mm, P < 0·05), septal basal thickness (9·0 ± 0·3, 15·9 ± 0·5, 11·2 ± 0·4 mm, P < 0·05) and left ventricular mass (143 ± 8, 255 ± 19, 169 ± 9 g, P < 0·05). In five patients, seven major cardiovascular events were observed. Compared to baseline, no significant difference was found in systolic (140 ± 35 vs 137 ± 18 mmHg) and diastolic (85 ± 18 vs 83 ± 10 mmHg) BP. An increase or a decrease in BP (>10 mmHg) was found in 36% and 39% of patients, respectively. The number of antihypertensive drugs had not changed [1 (0-3) vs 1 (0-4)]. Fewer patients received insulin (1 vs 3) or oral antiglycaemic drugs (2 vs 7).

CONCLUSION

Our data indicate that hypertension persists after removal of PCG/PGL in a substantial proportion of patients. Hypertensive heart disease is common, and cardiovascular events are frequent in patients with a history of PCC/PGL.

Variant on chromosome 9p is associated with left ventricular mass: results from two cohorts of essential hypertensive individuals

OBJECTIVES

It is well known that among hypertensive patients, an increased left ventricular mass (LVM) is a powerful predictor of cardiovascular morbidity and mortality. However, the mechanisms underlying LVM in hypertension are not completely understood, as the absolute value of blood pressure and other risk factors associated do not predict alone a definite LVM progression. Recently, the 9p21 chromosomal region has been consistently associated with coronary heart disease.

METHODS AND RESULTS

We examined the association of 384 single nucleotide polymorphisms (SNPs) in the short arm of chromosome 9 with LVM in 821 hypertensive individuals from northern Italy. We identified a SNP (rs894379) in the intronic region of the centlein, centrosomal protein (CNTLN) gene on chromosome 9p22, whose minor allele G is associated with an increased LVM. We performed a follow-up validation analysis for the top SNP in 1038 hypertensive individuals from southern Italy. We then combined the results and found a nominal association for rs894379 (β  =  2.46, P  =  0.0026).

CONCLUSION

We describe a new variant associated with echocardiography LVM. This result, though it needs to be further investigated, may improve our understanding of the genetic determination of this prognostically relevant trait.

Common variants in RYR1 are associated with left ventricular hypertrophy assessed by electrocardiogram

AIMS

To identify the genetic risk factors that influence the development of electrocardiographic (ECG) left ventricular hypertrophy (LVH), a major risk factor for cardiovascular (CV) morbidity and mortality.

METHODS AND RESULTS

We performed a genomewide association study (GWAS) of ECG-LVH, in which the community-based Korea Association REsource (KARE) study (8432 controls and 398 cases) was analysed by Affymetrix SNP array 5.0. The GWAS results were validated in hospital-based samples (597 controls and 207 cases). Fourteen single-nucleotide polymorphisms (SNPs) in eight genetic loci (5q35.1, 6p22.3-22.1, 8q24.2, 11p15, 11q21-22.1, 14q12, 17q11.2, and 19q13.1) were associated with ECG-LVH in the original GWAS study (P < 1 × 10(-5)). Of these SNPs, 12 were genotyped in the hospital sample. There was consistent association with the 19q13.1 region which contains RYR1 gene. The most significant SNP in the region was rs10500279, which had genomewide significance in the combined GWAS/replication sample [odds ratio = 1.58 (confidence interval: 1.35-1.85), P = 1.0 × 10(-8)]. Mutations in RYR1, which encodes a major Ca(2+) channel in the skeletal muscle, have been reported to correlate with CV diseases.

CONCLUSION

We performed the first GWAS for ECG-LVH, implicating the skeletal muscle Ca(2+) channel protein RYR1 as a genetic risk factor. These results might increase our understanding of the development of ECG-LVH.

Neuropeptide Y receptor Y2 gene polymorphism interacts with plasma neuropeptide Y levels in predicting left ventricular hypertrophy in dialysis patients

BACKGROUND

Neuropeptide Y (NPY) is a sympathetic neurotransmitter that acts on multiple receptors involved in cardiovascular remodelling and angiogenesis. Plasma levels of NPY are increased in patients with end-stage renal disease (ESRD) and are independently related to left ventricular hypertrophy (LVH) and incident cardiovascular events in these patients.

OBJECTIVE

To investigate the relationship between NPY receptor Y2 gene polymorphism and left ventricular mass index (LVMI) as well as the interaction between this polymorphism and plasma NPY in determining LVH in 189 ESRD patients.

RESULTS

LVMI was significantly higher (+12%, P = 0.03) in patients carrying the C allele than in those without C allele and was linearly associated with plasma NPY (P = 0.01). Interaction analysis showed a significant NPY-LVMI relationship in patients with the C allele, both at univariate (r = 0.27, P = 0.001) and multivariate (r = 0.21, P = 0.01) analyses, whereas no such relationship existed in patients without this allele. In fully adjusted analyses, a 10 pmol/l increase in plasma NPY entailed a 4.9 g/m increase in LVMI in patients with C allele, whereas the same change in NPY levels did not modify the NPY-LVMI link in patients without such allele (P = 0.009).

CONCLUSION

NPY receptor Y2 polymorphism is independently associated with LVMI and interacts with plasma levels of NPY in explaining the variability of LVH in ESRD. These results offer a genetic basis to the hypothesis that NPY is causally implicated in the pathogenetic pathway leading to LVH in ESRD patients.

Novel genetic variants contributing to left ventricular hypertrophy: the HyperGEN study

OBJECTIVES

To identify genes contributing to variation in echocardiographic left ventricular mass and related traits using linkage and linkage disequilibrium analysis in sibships ascertained on hypertension.

METHODS

The Hypertension Genetic Epidemiology Network (HyperGEN) Study of left ventricular hypertrophy characterized left ventricular mass, relative wall thickness (RWT), and aortic root diameter (ARD) with echocardiograms collected using a standardized protocol at four HyperGEN field centers. A high-throughput scanning fluorescence detector system genotyped 387 polymorphisms distributed throughout the genome. Linkage analyses were conducted once genotyping results became available for 885 siblings from 382 sibships.

RESULTS

Although single logarithm of the odds (LOD) score peaks of 1.2 or more were found on chromosomes 1, 4, 5, 6, 7, 8, 9, 10, 12, 14, 17, and 21, we observed a broad band of peaks in both ethnic groups (white and black) on chromosome 4 and selected candidate genes (NPY1R, NPY2R, NPY5R, SFRP2, CPE, IL15, and EDNRA) from this region. Using cases and controls from extremes of the left ventricular mass index, RWT, and ARD distributions, we assessed associations with these phenotypes and haplotype-tagging single-nucleotide polymorphisms (SNPs) in the candidates. Among blacks, SNPs in IL15, NPY2R, and NPY5R showed strong evidence for association (P < 0.005); all candidates except EDNRA showed suggestive association (P < 0.05). In whites, NPY2R, NPY5R, and SFRP2 SNPs offered suggestive evidence of association with one or more traits (P < 0.05).

CONCLUSION

Genetic variation in NPY1R, NPY2R, NPY5R, CPE, IL15, and SFRP2, detected using linkage analysis in hypertensive siblings, was associated with left ventricular phenotypes in blacks and/or whites.

Genome-wide association study identifies single-nucleotide polymorphism in KCNB1 associated with left ventricular mass in humans: the HyperGEN Study

Background

We conducted a genome-wide association study (GWAS) and validation study for left ventricular (LV) mass in the Family Blood Pressure Program – HyperGEN population. LV mass is a sensitive predictor of cardiovascular mortality and morbidity in all genders, races, and ages. Polymorphisms of candidate genes in diverse pathways have been associated with LV mass. However, subsequent studies have often failed to replicate these associations. Genome-wide association studies have unprecedented power to identify potential genes with modest effects on left LV mass. We describe here a GWAS for LV mass in Caucasians using the Affymetrix GeneChip Human Mapping 100 k Set. Cases (N = 101) and controls (N = 101) were selected from extreme tails of the LV mass index distribution from 906 individuals in the HyperGEN study. Eleven of 12 promising (Q < 0.8) single-nucleotide polymorphisms (SNPs) from the genome-wide study were successfully genotyped using quantitative real time PCR in a validation study.

Results

Despite the relatively small sample, we identified 12 promising SNPs in the GWAS. Eleven SNPs were successfully genotyped in the validation study of 704 Caucasians and 1467 African Americans; 5 SNPs on chromosomes 5, 12, and 20 were significantly (P ≤ 0.05) associated with LV mass after correction for multiple testing. One SNP (rs756529) is intragenic within KCNB1, which is dephosphorylated by calcineurin, a previously reported candidate gene for LV hypertrophy within this population.

Conclusion

These findings suggest KCNB1 may be involved in the development of LV hypertrophy in humans.

Neuropeptide Y expression in phaeochromocytomas: relative absence in tumours from patients with von Hippel-Lindau syndrome

Phaeochromocytomas are rare neuroendocrine tumours that produce catecholamines and numerous secretory proteins and peptides, including neuropeptide Y (NPY), a vasoactive peptide with influences on blood pressure. The production of catecholamines and NPY by phaeochromocytomas is highly variable. This study examined influences of hereditary factors and differences in catecholamine production on tumour expression of NPY, as assessed by quantitative PCR, enzyme immunoassay and immunohistochemistry. Phaeochromocytomas included hereditary adrenaline-producing tumours (adrenergic phenotype) in multiple endocrine neoplasia type 2 (MEN 2), predominantly noradrenaline-producing tumours (noradrenergic phenotype) in von Hippel-Lindau (VHL) syndrome, and other adrenergic and noradrenergic tumours where there was no clear hereditary syndrome. NPY levels in phaeochromocytomas from VHL patients were lower (P<0.0001) than in those from MEN 2 patients for both mRNA (84-fold difference) and the peptide (99-fold difference). These findings were supported by immunohistochemistry. NPY levels were also lower in VHL tumours than in those where there was no hereditary syndrome. Relative absence of expression of NPY in phaeochromocytomas from VHL patients when compared with other groups appears to be largely independent of differences in catecholamine production and is consistent with a unique phenotype in VHL syndrome.

Piecemeal degranulation in human tumour pheochromocytes

Piecemeal degranulation (PMD) has been recognized in two cases of human pheochromocytoma from the adrenal medulla, which were studied by transmission electron microscopy. Tumour pheochromocytes presented a highly characteristic cytoplasmic admixture of normal resting granules, swollen granules with eroded matrices and enlarged empty containers. Chromaffin granules that appeared to be normal and altered granules maintained their individual structure, and did not fuse with each other or with the plasma membrane. In accordance with the currently accepted model for granule discharge during PMD, electron-dense or clear vesicles 30-150 nm in diameter were seen either attached to the surface of chromaffin granules and the plasma membrane or free in the cytosol. This is the first description of PMD in human adrenal chromaffin cells and, in addition, is the first report of PMD in tumour secretory cells. These findings add further to the concept that PMD may have a broader spectrum of expression than hitherto recognized.

Neuropeptide Y as a far-reaching neuromediator: from energy balance and cardiovascular regulation to central integration of weight and bone mass control mechanisms. Implications for human diseases

PURPOSE OF REVIEW

I review recent knowledge on the interference of neuropeptide Y with energy balance and cardiovascular and renal disease and on the central regulation of bone mass.

RECENT FINDINGS

Although neuropeptide Y is mainly seen as a vasoconstrictor, rats overexpressing the neuropeptide Y gene show reduced blood pressure and longer life span in comparison with control rats. Due to its strong mitogenic effects on vascular smooth muscle cells, neuropeptide Y induces occlusive lesions in a rat model of atherosclerosis induced by balloon angioplasty. The involvement of neuropeptide Y in experimental atherosclerosis is complex and may include also favourable, compensatory, mechanisms because, at physiological concentrations, it also activates a potent neoangiogenic response to ischemia. Subjects with a common genotype in the neuropeptide Y gene, which underlies increased intracellular neuropeptide Y storage, display slightly raised blood pressure, high serum cholesterol and increased carotid intima media thickness. In patients with end-stage renal disease high neuropeptide Y in plasma has been associated consistently with concentric left-ventricular hypertrophy and cardiovascular mortality. Finally, recent studies have shown that neuropeptide Y constitutes an important central regulator of bone mass and that it may be involved in inflammation and immune regulation.

SUMMARY

Evidence has accrued in experimental animals that altered neuropeptide Y is involved in obesity and the attendant metabolic complications. Recent data also suggest that this peptide may play a role in atherosclerosis and related cardiovascular complications.