GOAT induced ghrelin acylation regulates hedonic feeding

Ghrelin is an orexigenic hormone that regulates homeostatic and reward-related feeding behavior. Recent evidence indicates that acylation of ghrelin by the gut enzyme ghrelin O-acyl transferase (GOAT) is necessary to render ghrelin maximally active within its target tissues. Here we tested the hypothesis that GOAT activity modulates food motivation and food hedonics using behavioral pharmacology and mutant mice deficient for GOAT and the ghrelin receptor (GHSR). We evaluated operant responding following pharmacological administration of acyl-ghrelin and assessed the necessity of endogenous GOAT activity for operant responding in GOAT and GHSR-null mice. Hedonic-based feeding behavior also was examined in GOAT-KO and GHSR-null mice using a “Dessert Effect” protocol in which the intake of a palatable high fat diet “dessert” was assessed in calorically-sated mice. Pharmacological administration of acyl-ghrelin augmented operant responding; notably, this effect was dependent on intact GHSR signaling. GOAT-KO mice displayed attenuated operant responding and decreased hedonic feeding relative to controls. These behavioral results correlated with decreased expression of the orexin-1 receptor in reward-related brain regions in GOAT-KO mice. In summary, the ability of ghrelin to stimulate food motivation is dependent on intact GHSR signaling and modified by endogenous GOAT activity. Furthermore, GOAT activity is required for hedonic feeding behavior, an effect potentially mediated by forebrain orexin signaling. These data highlight the significance of the GOAT–ghrelin system for the mediation of food motivation and hedonic feeding.     

D-Lys-GHRP-6 antagonizes the effect of unacylated but not of acylated ghrelin on the growth of HECa10 murine endothelial cells

Recent studies demonstrate that ghrelin can be an endogenous regulator of angiogenesis. We studied direct effects of human acylated (hAG) and unacylated (hUAG) ghrelin, as well as of rat acylated ghrelin (rAG) on the growth of HECa10 murine endothelial cells. Ghrelin was applied separately or together with D-Lys³-GHRP-6, which is commonly used as an antagonist of ghrelin receptor type 1a – GHS-R1a. The growth of HECa10 cells was assessed with Mosmann and in selected study conditions also with BrdU and TUNEL methods. Both hAG and hUAG (10⁻⁵ M to 10⁻¹² M) inhibited the growth of HECa10 cells in 24 h and 72 h cultures. Similarly, rAG decreased the growth of the cells after 24 h (10⁻⁷ M and 10⁻¹¹ M), and after 72 h (10⁻⁷ M, 10⁻⁸ M and 10⁻¹¹ M). Unexpectedly, D-Lys³-GHRP-6 itself also inhibited the growth of these cells at 10⁻⁴ to 10⁻⁶ M in 24 h, 48 h (dose–response effect) and 72 h cultures. D-Lys³-GHRP-6 did not modify the inhibitory effect of rAG. However, D-Lys³-GHRP-6 at the concentration of 10⁻⁴ M diminished, abolished or even reversed the inhibitory effect of hUAG in 72 h culture and this was dependent on ghrelin concentrations. These data indicate that both AG and UAG have antiangiogenic properties at least at the level of endothelial growth, through decreased metabolic activity of the cells or stimulation of apoptosis. D-Lys³-GHRP-6 (inhibitor of GHS-R1a) seems not to be an appropriate antagonist in this experimental condition. Similar effects of these substances on HECa10 cells suggest that they are not mediated by GHS-R1a.     

Genetic studies on the ghrelin, growth hormone secretagogue receptor (GHSR) and ghrelin O-acyl transferase (GOAT) genes

Ghrelin is a 28 amino acid peptide hormone that is produced both centrally and peripherally. Regulated by the ghrelin O-acyl transferase enzyme, ghrelin exerts its action through the growth hormone secretagogue receptor, and is implicated in a diverse range of physiological processes. These implications have placed the ghrelin signaling pathway at the center of a large number of candidate gene and genome-wide studies which aim to identify the genetic basis of human heterogeneity. In this review we summarize the available data on the genetic variability of ghrelin, its receptor and its regulatory enzyme, and their association with obesity, stature, type 2 diabetes, cardiovascular disease, eating disorders, and reward seeking behavior.     

Relationship between total ghrelin and inflammation in hemodialysis patients

In hemodialysis (HD) patients studies have shown that plasma ghrelin is increased and it has been speculated that ghrelin levels might be related to systemic inflammation. The present study attempted to correlate the serum levels of total ghrelin with serum TNF-α and IL-6, and with nutritional status and body composition in HD patients. Forty-seven HD patients from a single dialysis unit (18 women, mean age 55.3 ± 12.2 yr; BMI 24.4 ± 4.2 kg/m²; % body fat 29.4 ± 7.4%) were studied and compared to 21 healthy subjects (12 women, 50.7 ± 15.7 yr and BMI 25.6 ± 4.0 kg/m²; % body fat 30.0 ± 5.7%). Biochemical data, serum total ghrelin, TNF-α and IL-6 levels were measured. The body composition was evaluated by dual energy X-ray absortiometry (DEXA) and energy and protein intake were evaluated. Patients showed elevated plasma ghrelin levels when compared to healthy subjects (1.14 ± 1.0 ng/mL vs 0.58 ± 0.4; p < 0.001). There was a positive correlation between ghrelin levels and TNF-α (r = 0.25; p < 0.04), IL-6 (r = 0.42; p < 0.02), and a negative correlation between TNF-α and protein intake (r = −0.28; p < 0.03), and energy intake (r = −0.34; p < 0.01). No correlation was observed with any aspect of body composition. Plasma ghrelin levels are elevated in HD patients and associated with the state of systemic inflammation. We suggest that the inflammatory state may affect ghrelin bioactivity and metabolism in hemodialysis patients.     

Attenuation of systemic morphine-induced analgesia by central administration of ghrelin and related peptides in mice

Ghrelin, an acylated 28-amino peptide secreted in the gastric endocrine cells, has been demonstrated to stimulate the release of growth hormone, increase food intake, and inhibit pro-inflammatory cascade, etc. Ghrelin mainly combines with its receptor (GHS-R1α) to play the role in physiological and pathological functions. It has been reported that ghrelin plays important roles in the control of pain through interaction with the opioid system in inflammatory pain and acute pain. However, very few studies show the effect of supraspinal ghrelin system on antinociception induced by intraperitoneal (i.p.) administration of morphine. In the present study, intracerebroventricular (i.c.v.) injection of ghrelin (0.1, 1, 10 and 100 nmol/L) produced inhibition of systemic morphine (6 mg/kg, i.p.) analgesia in the tail withdrawal test. Similarly, i.c.v. injection GHRP-6 and GHRP-2 which are the agonists of GHS-R1α, also decreased analgesia effect induced by morphine injected intraperitoneally in mice. Furthermore, these anti-opioid activities of ghrelin and related peptides were not blocked by pretreatment with the GHS-R1α selective antagonist [d-Lys³]-GHRP-6 (100 nmol/L, i.c.v.). These results demonstrated that central ghrelin and related peptides could inhibit the analgesia effect induced by intraperitoneal (i.p.) administration of morphine. The anti-opioid effects of ghrelin and related peptides do not interact with GHS-R1a. These findings may pave the way for a new strategy on investigating the interaction between ghrelin system and opioids on pain modulation.     

Recent advances in the phylogenetic study of ghrelin

To understand fully the biology of ghrelin, it is important to know the evolutionary history of ghrelin and its receptor. Phylogenetic and comparative genomic studies of mammalian and non-mammalian vertebrates are a useful approach to that end. Ghrelin is a hormone that has apparently evaded natural selection during a long evolutionary history. Surely ghrelin plays crucial physiological roles in living animals. Phylogenetic studies reveal the nature and evolutionary history of this important signaling system.     

Serum ghrelin and prediction of metabolic parameters in over 20-year follow-up

Ghrelin is a peptide hormone from the stomach, with an ability to release growth-hormone from the pituitary. Numerous cross-sectional studies indicate that ghrelin also has a role in metabolic abnormalities, such as metabolic syndrome and type 2 diabetes, but evidence for long-term effect is scarce. We investigated, whether ghrelin concentration measured in middle age would predict the development or absence of metabolic disturbances subsequently. Study population consisted of 600 middle-aged persons, and the follow-up time was approximately 21 years. Plasma total ghrelin concentration was measured at the baseline, and divided to tertiles. Numerous anthropometric and other clinical measurements (including blood pressure), and laboratory test were made both at the baseline and at the follow-up. After the follow-up the prevalence of high systolic blood pressure according to MetS IDF-criteria was the lowest in the highest ghrelin tertile, and the highest in the first (p < 0.03). When only subjects free of hypertension medication at baseline were considered, subjects belonging to the highest ghrelin tertile developed less new hypertension and high blood pressure according to IDF-criteria as well as medication for it during the follow-up (p < 0.05). Although serum insulin levels were negatively correlated to ghrelin levels at both points in time (p < 0.001 at baseline and p = 0.003 at follow-up), plasma ghrelin concentration did not predict the development of abnormalities in glucose tolerance. The association with ghrelin and metabolic syndrome was lost during the follow-up. In conclusion, our results suggest high ghrelin to be protective against the development of hypertension in the long-term follow-up.     

Improved insulin sensitivity and metabolic flexibility in ghrelin receptor knockout mice

Stimulation of the ghrelin receptor (GhrR) by ghrelin results in a variety of metabolic changes including increased food intake, fat storage and insulin resistance. Loss of ghrelin signaling is protective against diet-induced obesity, suggesting that ghrelin plays a significant homeostatic role in conditions of metabolic stress. We examined glycemic control in GhrR −/− mice fed a high-fat diet, and used indirect calorimetry to assess fuel substrate usage and energy expenditure. GhrR −/− mice fed a high-fat diet had several measures of greater insulin sensitivity, including: lower fasted blood glucose and plasma insulin, lower %Hb_A1c, lower insulin levels during glucose tolerance tests, and improved performance in hyperinsulinemic-euglycemic and hyperglycemic clamp studies. GhrR −/− mice fed a high-fat diet did not develop hepatic steatosis and had lower total cholesterol, relative to controls. Furthermore, GhrR −/− mice demonstrated a lower intestinal triglyceride secretion rate of dietary lipid. GhrR −/− mice have higher respiratory quotients (RQ), indicating a preference for carbohydrate as fuel. The range of RQ values was wider in GhrR −/− mice, indicating greater metabolic flexibility and insulin sensitivity in these animals. We therefore propose that loss of ghrelin signaling promotes insulin sensitivity and metabolic flexibility, and protects against several fatty diet-induced features of metabolic syndrome due to convergent changes in the intake, absorption and utilization of energy.     

Coronary vasoconstrictor effect of ghrelin is not mediated by growth hormone secretagogue receptor 1a type in dogs

Ghrelin (GHR) is a recently discovered endocrine regulatory peptide of gastrointestinal origin with multiple functions including cardiovascular effects. However, contradictory data are available on the vascular actions of GHR in different organs and species. The aim of this study was to characterize the direct effect of the peptide on the canine coronary bed and to evaluate the role of the growth hormone secretagogue receptor (GHS-R) in the effect of GHR on coronary arterioles. The presence of GHS-R1a and 1b subtypes in canine coronary arterioles was investigated using Western blotting and immunohistochemistry. Responses of coronary arterioles with spontaneous and elevated vascular tone (the latter evoked by the thromboxane mimetic agent U46619, 10⁻⁷-10⁻⁶ mol/l) to GHR (10⁻⁹-3 × 10⁻⁷ nmol/l) were recorded by video-microscopy as changes of vessel diameter. Positive immunostaining for both GHS-R subtypes was found in the wall of intramural arterioles. The microarteriographic study results showed that GHR alone could not elicit any significant effect on vessel diameter of arterioles with spontaneous tone. However, when vascular smooth muscle was preconstricted by the thromboxane mimetic agent U46619, administration of GHR induced further constriction (+31 ± 9% increase in contraction p < 0.01). This was not abolished by the specific blockade of GHS-R1a by d-Lys³-GHRP-6 (5 × 10⁻⁶ mol/l). The results suggest that GHR induces tone-dependent constriction of canine coronary arterioles which is mediated by a receptor other than GHS-R1a.     

Preclinical gastrointestinal prokinetic efficacy and endocrine effects of the ghrelin mimetic RM-131

Aims

The 28 amino acid hormone ghrelin, the natural ligand for the growth hormone secretagogue, or ghrelin receptor (GHR), has diverse physiological functions, including a possible role as a gastrointestinal prokinetic. The synthetic ghrelin mimetic RM-131 is in Phase II clinical trials for treatment of diabetic gastroparesis and other gastrointestinal (GI) disorders. We aimed to determine the relative potency of RM-131, when compared to other GI ghrelin mimetics, to predict efficacy and determine the role of RM-131 in models of inflammatory bowel disease.

Main methods

We evaluated and compared ghrelin, RM-131 and other synthetic ghrelin mimetics for their prokinetic potency in models of gastrointestinal disorders in the rat and we evaluated the endocrine (rats and dogs) and anti-inflammatory effects (mice) of the ghrelin mimetic RM-131.

Key findings

The pentapeptide RM-131 increased gastric emptying in rodent models of ileus. RM-131 is about 100-fold more potent than human ghrelin and is 600 to 1800-fold more potent, when compared to several investigational ghrelin mimetics tested in clinical trials. RM-131 has anti-inflammatory effects and significantly increases survival and reduces macroscopic markers of tissue damage in a TNBS model of inflammatory bowel disease. RM-131 treatment shows a transient increase in growth hormone levels in Beagle dogs and rats, returning to baseline upon chronic treatment. Significant effects on glucose and insulin are not observed in chronic studies.

Significance

RM-131's potency, efficacy and endocrine profile, are promising attributes for the treatment of diverse functional gastrointestinal disorders in humans.     

Sulfated gastrin stimulates ghrelin and growth hormone release but inhibits insulin secretion in cattle

This study was designed to determine the effects of gastrin on the circulating levels of ghrelin, growth hormone (GH), insulin, glucagon and glucose in ruminants. Two experiments were done in eight Holstein steers. Animals were randomly assigned to receive intravenous bolus injections: (1) 0.1% bovine serum albumin in saline as vehicle, 0.8, 4.0 and 20.0 μg/kg body weight (BW) of bovine sulfated gastrin-34; (2) vehicle, 0.53 μg/kg BW of bovine sulfated gastrin-17 alone or combined with 20.0 μg/kg BW of [d-Lys³]-GHRP-6, the selective antagonist of GHS-R1a. Blood samples were collected from −10 to 150 min relative to injection time. Concentrations of acyl and total ghrelin in response to gastrin-34 injection were significantly increased in a dose-dependent manner. Concentrations of GH were also markedly elevated by gastrin-34 injection; however, the effect of 20.0 μg/kg was weaker than that of 4.0 μg/kg. The three doses of gastrin-34 equally decreased insulin levels within 15 min and maintained the level until the time of last sampling. Gastrin-34 had no effect (P > 0.05) on the levels of glucagon and glucose. Levels of acyl ghrelin increased after administration of gastrin-17 alone or combined with [d-Lys³]-GHRP-6; however, [d-Lys³]-GHRP-6 did not block the elevation of GH by gastrin-17. The present results indicate that sulfated gastrin stimulates both ghrelin and GH release, but the GHS-R1a may not contribute to the release of GH by gastrin. Moreover, sulfated gastrin seems to indirectly maintain the homeostasis of blood glucose through the down-regulation of insulin in ruminants.     

Neuroendocrine and metabolic activities of ghrelin gene products

Acylated ghrelin (AG) is a 28 amino acid gastric peptide a natural ligand for the growth hormone secretagogue (GHS) receptor type 1a (GHS-R1a), endowed with GH-secreting and orexigenic properties. Besides, ghrelin exerts several peripheral metabolic actions, including modulation of glucose homeostasis and stimulation of adipogenesis. Notably, AG administration causes hyperglycemia in rodents as in humans. Ghrelin pleiotropy is supported by a widespread expression of the ghrelin gene, of GHS-R1a and other unknown ghrelin binding sites. The existence of alternative receptors for AG, of several natural ligands for GHS-R1a and of acylation-independent ghrelin non-neuroendocrine activities, suggests that there might be a complex ‘ghrelin system’ not yet completely explored. Moreover, the patho-physiological implications of unacylated ghrelin (UAG), and obestatin (Ob), the other two ghrelin gene-derived peptides, need to be clarified. Within the next few years, we may better understand the ‘ghrelin system’, where we might envisage clinical applications.     

In vivo characterization of the effects of ghrelin on the modulation of acute pain at the supraspinal level in mice

Ghrelin, an acylated peptide produced in the stomach, increases food intake and growth hormone secretion, inhibits pro-inflammatory cascade, etc. Ghrelin and its receptor (GHS-R1a) mRNA were found in the area related to the regions for controlling pain transmission, such as the hypothalamus, the midbrain, the spinal cord, etc. Ghrelin has been shown to have antinociceptive activity and also anti-inflammatory properties in inflammatory pain and chronic neuropathic pain. Therefore, the aim of the present study was to investigate the effects of ghrelin for the first time in the acute pain modulation at the supraspinal level, using the tail withdrawal test and hot-plate test in mice. Intracerebroventricular (i.c.v.) administration of ghrelin (mouse, 0.1–3 nmol) produced a dose- and time-related antinociceptive effect in the tail withdrawal test and hot-plate test, respectively. Antinociceptive effect elicited by ghrelin (i.c.v., 1 nmol) was significantly antagonized by opioid receptor antagonist naloxone (i.c.v., 10 nmol co-injection or i.p., 10 mg/kg, 10 min prior to ghrelin) in both tail withdrawal test and hot-plate test. At these doses, naloxone significantly antagonized the antinociceptive effect induced by morphine (i.c.v., 3 nmol). Ghrelin (i.c.v., 1 nmol)-induced antinociception was significantly antagonized by co-injection with 10 nmol [d-Lys3]-GHRP-6, the selective antagonist of GHS-R1a identified more recently, while [d-Lys3]-GHRP-6 (10 nmol) alone induced neither hyperalgesia nor antinociception. Overall this data indicate that ghrelin could produce antinociception through an interaction with GHS-R1a and with the central opioid system. Thus ghrelin may be a promising peptide for developing new analgesic drugs.     

Individual plasma ghrelin changes in the same patients in hyperthyroid,hypothyroid and euthyroid state

Ghrelin is a multifunctional peptide of widespread expression. Since it has been shown to influence energy homeostatis, its potential role in thyroid dysfunction may have clinical significance. In this study, plasma ghrelin changes have been analyzed in the same patients in three different thyroid states for the first time. The study group consisted of 16 patients who had been diagnosed with hyperthyroidism, were treated with radioiodine, developed hypothyroidism after treatment, and finally became euthyroid on l-thyroxine substitution. In the initial state of hyperthyroidism plasma ghrelin levels correlated negatively with fT₃ and fT₄. In hypothyroidism ghrelin concentration increased significantly (p < 0.05). Although the mean value of plasma ghrelin tended to decrease in the euthyroid state, the individual difference between hypothyroidism and euthyroidism was not significant. Plasma ghrelin in euthyroidism was still significantly higher than in hyperthyroidism (p < 0.05), and correlated positively with ghrelin levels in hyperthyroidism and hypothyroidism. In our opinion, plasma ghrelin fluctuations may reflect metabolic changes in patients with thyroid dysfunction. Moreover, it cannot be excluded that in thyroid disorders ghrelin acts as a compensatory factor, helping to balance metabolic disturbances.     

Central and peripheral effects of ghrelin on energy balance, food intake and lipid metabolism in teleost fish

Ghrelin was first identified and characterized from rat stomach as an endogenous ligand for the growth hormone secretagogue receptor. Ghrelin and its receptor system are present not only in peripheral tissues such as stomach and intestine, but also in the central nervous system of mammals. Interestingly, administration of ghrelin induces an orexigenic effect and also modifies locomotor activity, suggesting its involvement in feeding control and the regulation of energy balance, in addition to the regulation of growth hormone release. Information about ghrelin in non-mammals, such as teleost fish, has also been increasing, and important data have been obtained. An understanding of the evolutionary background of the energy regulation system and the central and peripheral roles of ghrelin in teleost fish could provide indications as to their roles in mammals, particularly humans. In this review, we overview the central and peripheral effects of ghrelin on energy balance, locomotor activity, and lipid metabolism in teleost fish.     

The octanoylated energy regulating hormone ghrelin: An expanded view of ghrelin’s biological interactions and avenues for controlling ghrelin signaling

Ghrelin is a small peptide hormone that requires a unique post-translational modification, serine octanoylation, to bind and activate the GHS-R1a receptor. Initially demonstrated to stimulate hunger and appetite, ghrelin-dependent signaling is implicated in a variety of neurological and physiological processes influencing diseases such as diabetes, obesity, and Prader-Willi syndrome. In addition to its cognate receptor, recent studies have revealed ghrelin interacts with a range of binding partners within the bloodstream. Defining the scope of ghrelin’s interactions within the body, understanding how these interactions work in concert to modulate ghrelin signaling, and developing molecular tools for controlling ghrelin signaling are essential for exploiting ghrelin for therapeutic effect. In this review, we discuss recent findings regarding the biological effects of ghrelin signaling, outline binding partners that control ghrelin trafficking and stability in circulation, and summarize the current landscape of inhibitors targeting ghrelin octanoylation.     

Sequence, genomic organization and expression of two channel catfish, Ictalurus punctatus, ghrelin receptors

Two ghrelin receptor (GHS-R) genes were isolated from channel catfish tissue and a bacterial artificial chromosome (BAC) library. The two receptors were characterized by determining tissue distribution, ontogeny of receptor mRNA expression, and effects of exogenous homologous ghrelin administration on target tissue mRNA expression. Analysis of sequence similarities indicated two genes putatively encoding GHS-R1 and GHS-R2, respectively, which have been known to be present in zebrafish. Organization and tissue expression of the GHS-R1 gene was similar to that reported for other species, and likewise yielded two detectable mRNA products as a result of alternative splicing. Expression of both full-length, GHS-R1a, and splice variant, GHS-R1b, mRNA was highest in the pituitary. Gene organization of GHS-R2 was similar to GHS-R1, but no splice variant was identified. Expression of GHS-R2a mRNA was highest in the Brockmann bodies. GHS-R1a mRNA was detected in unfertilized eggs and throughout embryogenesis, whereas GHR-R2a mRNA was not expressed in unfertilized eggs or early developing embryos and was the highest at the time of hatching. Catfish intraperitoneally injected with catfish ghrelin-Gly had greater mRNA expression of GHS-R1a in pituitaries at 2 h and Brockmann bodies at 4 h, and of GHS-R2a in Brockmann bodies at 6 h post injection. Amidated catfish ghrelin (ghrelin-amide) had no observable effect on expression of either pituitary receptor; however, GHS-R1a and GHS-R2a mRNA expression levels were increased 4 h post injection of ghrelin-amide in Brockmann bodies. This is the first characterization of GHS-R2a and suggests regulatory and functional differences between the two catfish receptors.     

Characterization of a far-red analog of ghrelin for imaging GHS-R in P19-derived cardiomyocytes

Ghrelin and its receptor, the growth hormone secretagogue receptor (GHS-R), are expressed in the heart, and may function to promote cardiomyocyte survival, differentiation and contractility. Previously, we had generated a truncated analog of ghrelin conjugated to fluorescein isothiocyanate for the purposes of determining GHS-R expression in situ. We now report the generation and characterization of a far-red ghrelin analog, [Dpr³(octanoyl), Lys¹⁹(Cy5)]ghrelin (1–19), and show that it can be used to image changes in GHS-R in developing cardiomyocytes. We also generated the des-acyl analog, des-acyl [Lys¹⁹(Cy5)]ghrelin (1–19) and characterized its binding to mouse heart sections. Receptor binding affinity of Cy5-ghrelin as measured in HEK293 cells overexpressing GHS-R1a was within an order of magnitude of that of fluorescein-ghrelin and native human ghrelin, while the des-acyl Cy5-ghrelin did not bind GHS-R1a. Live cell imaging in HEK293/GHS-R1a cells showed cell surface labeling that was displaced by excess ghrelin. Interestingly, Cy5-ghrelin, but not the des-acyl analog, showed concentration-dependent binding in mouse heart tissue sections. We then used Cy5-ghrelin to track GHS-R expression in P19-derived cardiomyocytes. Live cell imaging at different time points after DMSO-induced differentiation showed that GHS-R expression preceded that of the differentiation marker aMHC and tracked with the contractility marker SERCA 2a. Our far-red analog of ghrelin adds to the tools we are developing to map GHS-R in developing and diseased cardiac tissues.     

High plasma ghrelin protects from coronary heart disease and Leu72Leu polymorphism of ghrelin gene from cancer in healthy adults during the 19 years follow-up study

The aim of our investigation was to find out if ghrelin concentrations or polymorphisms predict the future risk for cardiovascular diseases and cancer in a population-based cohort initiated in 1991 (491 hypertensive and 513 control subjects). Total mortality and hospital events were followed up for 19 years. Fasting total ghrelin concentrations were determined and Arg51Gln, Leu72Met and −501A > C polymorphisms identified. Cox regression analysis was performed. The mean value in the control cohort was 674 pg/ml whereas in the hypertensive cohort it was 661 pg/ml. The associations found suggest that in the controls the highest ghrelin quartile protected from CHD (coronary heart disease). The results were significant without or with adjustments for age, sex, smoking, systolic blood pressure and LDL cholesterol, BMI, type 2 diabetes or QUICK index. C/C variant of the promoter associated with the prevention of IHD (ischemic heart disease) in the hypertensive group (p < 0.05). The controls with the Leu72Leu genotype had less cancer (p < 0.05). In conclusion, high plasma ghrelin concentration was related to protection from CHD and Leu72Leu genotype to prevention of cancer in healthy adults during the 19 years follow-up. C/C promoter protects from IHD in the hypertensive subjects.