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Meta-analyses from 2018–2022 have shown that obesity increases the risk of various cancers such as acute myeloid lymphoma, chronic myeloid lymphoma, diffuse beta cell lymphoma, Hodgkin's lymphoma, leukemia, multiple myeloma, non-Hodgkin's lymphoma, bladder, breast, cholangiocarcinoma, colorectal, ovarian, esophageal, kidney, liver, prostate, thyroid, and uterus. Contextually, obesity, and its comorbidities, is the largest, most lethal pandemics in the history of mankind; hence, identification of underlying mechanisms is needed to adequately address this global health threat. Herein, we present the metabolic and hormonal mechanisms linked to obesity that might etiologically contribute to neoplasia, including hyperinsulinemia and putative places in the insulin-signaling pathway. Excess insulin, acting as a growth factor, might contribute to tumorigenesis, while abundant ATP and GDP supply the additional energy needed for proliferation of rapidly dividing cells. Our observations in the Ecuadorian cohort of subjects with Laron syndrome (ELS) prove that obesity does not always associate with increased cancer risk. Indeed, despite excess body fat from birth to death, these individuals display a diminished incidence of cancer when compared to their age- and sex-matched relatives. Furthermore, in cell cultures exposed to potent oxidizing agents, addition of ELS serum induces less DNA damage as well as increased apoptosis. ELS individuals have absent growth hormone (GH) counter-regulatory effects in carbohydrate metabolism due to a defective GH receptor. The corresponding biochemical phenotype includes extremely low basal serum concentrations of insulin and insulin-like growth factor-I, lower basal glucose and triglyceride (TG) levels, and diminished glucose, TG, and insulin responses to orally administered glucose or to a mixed meal.

AIMS: We examined the effect of growth hormone (GH) counter-regulation on carbohydrate metabolism in individuals with life-long diminished insulin secretion (DIS).METHODS: Adults homozygous for the E180 splice site mutation of GHR [Laron syndrome (LS)], adults with a gain-of-function mutation in CDKN1c [Guevara-Rosenbloom syndrome (GRS)], and controls were evaluated for body composition, leptin, total and high molecular weight (HMW) adiponectin, insulin-like growth factor (IGF) axis molecules, and a 5-hour oral glucose tolerance test (OGTT), with measurements of glucose, insulin, glucagon, ghrelin, pancreatic polypeptide, gastric inhibitory peptide, glucagon-like peptide-1, peptide YY, and islet amyloid polypeptide (IAPP).RESULTS: Both syndromic cohorts displayed DIS during OGTT. LS subjects had higher serum concentrations of total and HMW adiponectin, and lower levels of IGF-I, IGF-II, and IGF-Binding Protein-3 than individuals in other study groups. Furthermore, they displayed normal glycemic responses during OGTT with the lowest IAPP secretion. In contrast, individuals with GRS had higher levels of protein glycation, deficient glucose control during OGTT, and increased secretion of IAPP.CONCLUSIONS: A distinct metabolic phenotype depending on GH counter-regulatory status, associates with diabetes development and excess glucose-induced IAPP secretion.

Chagas disease (CD) is one of the most devasting parasitic diseases in the Americas affecting 7 to 8 million people worldwide. In vitro and in vivo experiments have demonstrated that decreased growth hormone (GH) serum levels occur as CD progresses. Interestingly, inactivating mutations in the GH receptor in humans induce Laron syndrome (LS), a clinical entity characterized by increased GH and decreased insulin growth factor-1 (IGF-1) serum levels. The largest cohort of LS subjects lives in the southern provinces of Ecuador. Remarkably, CD prevalence in these individuals is diminished despite living in highly endemic areas. In the current ex vivo study, we employed serum from GHR -/- mice, also known as LS mice (a model of GH resistance with high GH and low IGF-1 levels), and serum from bovine GH (bGH) transgenic mice (high GH and IGF-1), to test the effect on T. cruzi infection. We infected mouse fibroblast L-cells treated with serum from each type of mouse with metacyclic trypomastigotes from Trypanosoma cruzi (etiological CD infectious agent). Treatment with GHR-/- serum (LS mice) significantly decreased infection by 28% compared to 48% seen in control wild-type mouse serum (WT). Treatment with bGH mouse serum significantly decreased infection by only 41% compared to 54% from WT controls. Our results suggest that high GH and low IGF-1 in blood circulation, as typically seen in LS individuals, confers partial protection against T. cruzi infection.

Growth hormone (GH) has been used for over 35 years, and its safety and efficacy has been studied extensively. Experimental studies showing the permissive role of GH/insulin-like growth factor 1 (IGF-I) in carcinogenesis have raised concerns regarding the safety of GH replacement in children and adults who have received treatment for cancer and those with intracranial and pituitary tumours. A consensus statement was produced to guide decision-making on GH replacement in children and adult survivors of cancer, in those treated for intracranial and pituitary tumours and in patients with increased cancer risk. With the support of the European Society of Endocrinology, the Growth Hormone Research Society convened a Workshop, where 55 international key opinion leaders representing 10 professional societies were invited to participate. This consensus statement utilized: (1) a critical review paper produced before the Workshop, (2) five plenary talks, (3) evidence-based comments from four breakout groups, and (4) discussions during report-back sessions. Current evidence reviewed from the proceedings from the Workshop does not support an association between GH replacement and primary tumour or cancer recurrence. The effect of GH replacement on secondary neoplasia risk is minor compared to host- and tumour treatment-related factors. There is no evidence for an association between GH replacement and increased mortality from cancer amongst GH-deficient childhood cancer survivors. Patients with pituitary tumour or craniopharyngioma remnants receiving GH replacement do not need to be treated or monitored differently than those not receiving GH. GH replacement might be considered in GH-deficient adult cancer survivors in remission after careful individual risk/benefit analysis. In children with cancer predisposition syndromes, GH treatment is generally contraindicated but may be considered cautiously in select patients.

The Ecuadorian cohort of subjects with LS has taught us valuable lessons since the late 80's. We have learned about migration of Sephardic Jews to our country, their isolation in remote hamlets and further inbreeding. These geographical, historical and social determinants induced dissemination of a growth hormone (GH) receptor mutation which widely occurred in those almost inaccessible villages. Consequently, the world's largest Laron syndrome (LS) cohort emerged in Loja and El Oro, two of the southern provinces of Ecuador. We have been fortunate to study these patients since 1987. New clinical features derived from GH insensitivity, their growth patterns as well as treatment with exogenous insulin-like growth factor I (IGF-I) have been reported. Novel biochemical characteristics in the field of GH insensitivity, IGFs, IGF binding proteins (BP) and their clinical correlates have also been described. In the last few years, studies on the morbidity and mortality of Ecuadorian LS adults surprisingly demonstrated that despite obesity, they had lower incidence of diabetes and cancer than their relatives. These events were linked to their metabolic phenotype of elevated but ineffective GH concentrations and low circulating IGF-I and IGFBP-3. It was also noted that absent GH counter-regulation induces a decrease in insulin resistance (IR), which results in low but highly efficient insulin levels which properly handle metabolic substrates. We propose that the combination of low IGF-I signaling, decreased IR, and efficient serum insulin concentrations are reasonable explanations for the diminished incidence of diabetes and cancer in these subjects.

Chagas disease (CD) is caused by the protozoan parasite, Trypanosoma cruzi. It affects 7 to 8 million people worldwide and leads to approximately 50,000 deaths per year. In vitro and in vivo studies had demonstrated that Trypanosoma cruziinfection causes an imbalance in the hypothalamic-pituitary-adrenal (HPA) axis that is accompanied by a progressive decrease in growth hormone (GH) and prolactin (PRL) production. In humans, inactivating mutations in the GH receptor gene cause Laron Syndrome (LS), an autosomal recessive disorder. Affected subjects are short, have increased adiposity, decreased insulin-like growth factor-I (IGFI), increased serum GH levels, are highly resistant to diabetes and cancer, and display slow cognitive decline. In addition, CD incidence in these individuals is diminished despite living in highly endemic areas. Consequently, we decided to investigate the in vitro effect of GH/IGF-I on T. cruzi infection.We first treated the parasite and/or host cells with different peptide hormones including GH, IGFI, and PRL. Then, we treated cells using different combinations of GH/IGF-I attempting to mimic the GH/IGF-I serum levels observed in LS subjects.We found that exogenous GH confers protection against T. cruzi infection. Moreover, this effect is mediated by GH and not IGFI. The combination of relatively high GH (50 ng/ml) and low IGF-I (20 ng/ml), mimicking the hormonal pattern seen in LS individuals, consistently decreased T. cruzi infection in vitro.The combination of relatively high GH and low IGF-I serum levels in LS individuals may be an underlying condition providing partial protection against T. cruzi infection.

Background: Androgenetic alopecia (AGA) is the most common hair loss disorder seen in men. It can have an early onset but has also been associated with ageing and senescence. It often induces pronounced psychological impact. ALRV5XR, a new hair loss treatment herein evaluated, was designed to target multiple molecular pathways involved in hair growth and hair follicle stem cell biology. The main objectives of the study were the assessment of safety and efficacy profiles of ALRV5XR in men.Methods: This 24-week, parallel randomised, placebo-controlled, double-blinded clinical trial was performed in a USA community clinic. Healthy men (age 22-65) with AGA and belonging to the Hamilton-Norwood (HN) classification I-VII and Fitzpatrick skin type (FST) I-VI, were randomly allocated in a 1:1 ratio into ALRV5XR or placebo treatment groups. Dermatologist assessment, phototrichograms, and blood samples were obtained in a blinded fashion at baseline, 12 and 24 weeks. Subjects were given a masked treatment consisting of oral capsules, shampoo, conditioner, and follicle serum, which was intended for daily use. Efficacy was assessed via absolute and per cent changes in terminal hair (TH) density, and response rates. The trial was registered with clinicaltrials.gov (NCT04450589) and is completed.Findings: Forty-six subjects were enroled in the study, 23 allocated to the ALRV5XR treatment and 23 to the placebo group. Enrolment occurred from April 11 to October 23, 2018. Thirty-six subjects completed the trial (17 ALRV5XR, 19 placebo) and 11 subjects in each group were evaluable for TH outcomes. At 24 weeks, the absolute change in TH density improved by 21.0 THs/cm(2) (95% CI: 9.2-32.8; p = 0.0014), and the relative density increased by 16.4% (95% CI: 7.4%-25.5%; p = 0.0012). The odds ratio for being a responder ( >= 0 change) was 87.4. TH density increased linearly and was not affected by HN, FST, ethnicity, age, or body mass index. All subjects in the ALRV5XR group responded to treatment while 81.8% of the placebo group decreased TH density. ALRV5XR induced statistically significant changes in both decrease in vellus hair (VH) density as well as in concomitant increase of the TH/VH ratio when compared to placebo. ALRV5XR was well tolerated, and no adverse events were observed.Interpretation: ALRV5XR treatment resulted in clinically significant TH regrowth in men with AGA. Furthermore, it appeared to reverse the characteristic hair miniaturisation seen in this condition. When compared to results of published trials of standard therapy, ALRV5XR showed a multi-fold increase both in efficacy and in response rates. In addition, the continuance of TH regrowth from 12 to 24 weeks suggests that the normal structure and function of non-productive telogen follicles is restored and that a normal hair phenotype may be attained by extended ALRV5XR treatment. (C) 2021 The Author(s). Published by Elsevier Ltd.

Background Scalp hair loss (alopecia) in women is a common ageing and senescing condition. It usually presents as androgenetic alopecia (AGA) or telogen effluvium (TE) and often has pronounced psychological consequences. ALRV5XR is a novel treatment aiming to regenerate a normal hair phenotype by targeting multiple molecular pathways linked to hair growth promotion and hair follicle stem cell activation. The primary objectives of this 24-week trial were to evaluate the safety and efficacy of ALRV5XR in terminal hair (TH) regrowth in women with AGA or TE. Methods This randomised, double-blind, placebo-controlled trial was performed in a USA community clinic. Healthy women 18-65 years of age with AGA or TE of Ludwig classification I-II and Fitzpatrick skin type I-VI were enrolled. They were allocated in a 1:1 ratio into ALRV5XR or placebo treatment groups using a random number table. Masked dermatologist assessments, phototrichograms and blood samples were obtained at baseline, 12 and 24 weeks. Subjects were given a masked treatment regimen of oral capsules, shampoo, conditioner and follicle serum for daily administration. Main outcomes were absolute and per cent changes in TH density and response rates. The trial was registered with clinicaltrials.gov (NCT04450602) and is completed. Findings 46 subjects (23 ALRV5XR, 23 placebo) were enrolled between April 3 and October 20, 2018. Five subjects dropped out and two were non-compliant. Thirty-nine subjects completed the trial (18 ALRV5XR, 21 placebo). At 24 weeks, the absolute change in TH density improved by 30·1THs/cm2 (95% CI: 15·1–45·1; p=0·0002), and the relative density increased by 19·7% (95% CI: 8·0%–31·4%; p=0·0016). The odds ratio for being a responder (≥0 change) was 2·7. Efficacy increased 133% from week 12 to 24. Efficacy outcomes were similar in AGA and TE subjects. 66·7% of the ALRV5XR group responded by regrowing 40THs/cm2 or more hair. No adverse events were reported. Interpretation In women with AGA or TE, ALRV5XR treatment significantly increased hair regrowth without adverse events. ALRV5XR displayed a multi-fold improved efficacy and response rate when compared to published trials of standard therapy. Progressive acceleration of TH regrowth suggests regeneration of the structure and function of non-productive telogen follicles and prolonged treatment may restore a normal hair phenotype. Funding This clinical trial was funded by Arbor Life Labs, Toronto, Ontario, Canada.

Human size is achieved by the coordinated expression of many genes. From conception to adulthood, a given genomic endowment is modified by highly variable environmental circumstances. During each stage of a person's life, distinct nutritional and hormonal influences continuously shape growing physical features until mature characteristics are attained. Underlying processes depend on precise provision of substrates and energy extracted by insulin action from nutrients, which allows cell proliferation, differentiation, and survival, under the concerted actions of growth hormone and insulin-like growth factor-I (IGF-I). It should be noted that growth and metabolic signaling pathways are interdependent and superimposed at multiple levels. Attainment of a fully developed human phenotype should be considered as a harmonious increment in body size rather than a simple increase in height. From this perspective we herein analyze adult features of individuals with an inactive growth hormone receptor, who consequently have severely diminished concentrations of serum insulin and endocrine IGF-I.

The Ecuadorian cohort of subjects with LS has taught us valuable lessons since the late 80's. We have learned about migration of Sephardic Jews to our country, their isolation in remote hamlets and further inbreeding. These geographical, historical and social determinants induced dissemination of a growth hormone (GH) receptor mutation which widely occurred in those almost inaccessible villages. Consequently, the world's largest Laron syndrome (LS) cohort emerged in Loja and El Oro, two of the southern provinces of Ecuador. We have been fortunate to study these patients since 1987. New clinical features derived from GH insensitivity, their growth patterns as well as treatment with exogenous insulin-like growth factor I (IGF-I) have been reported. Novel biochemical characteristics in the field of GH insensitivity, IGFs, IGF binding proteins (BP) and their clinical correlates have also been described. In the last few years, studies on the morbidity and mortality of Ecuadorian LS adults surprisingly demonstrated that despite obesity, they had lower incidence of diabetes and cancer than their relatives. These events were linked to their metabolic phenotype of elevated but ineffective GH concentrations and low circulating IGF-I and IGFBP-3. It was also noted that absent GH counter-regulation induces a decrease in insulin resistance (IR), which results in low but highly efficient insulin levels which properly handle metabolic substrates. We propose that the combination of low IGF-I signaling, decreased IR, and efficient serum insulin concentrations are reasonable explanations for the diminished incidence of diabetes and cancer in these subjects.

Individuals affected with two genetic syndromes identified in Ecuador have severe short stature and diminished insulin secretion, along with essentially different GH counterregulatory effects on insulin action, which leads to the appearance of opposing metabolic phenotypes. In the case of Laron syndrome, subjects have enhanced insulin sensitivity and diminished incidence of type 2 diabetes mellitus. In the other clinical entity, individuals have innate insulin resistance, a varying degree of carbohydrate metabolism disturbances, glucose intolerance, and eventually insulin-resistant diabetes mellitus. Since both groups have diminished insulin secretion, the standard homeostatic minimal models for assessment of insulin sensitivity and resistance were used to see if they could properly identify the metabolic status, especially considering that these methodologies are simple and non-invasive procedures. Methods Fasting insulin concentrations, fasting glucose/fasting insulin ratio and various minimal models were determined in individuals from the two syndromic cohorts, as well as in a control group made of first-degree normal relatives of the insulin-resistant phenotype subjects. Results The metabolic characteristics of enhanced insulin sensitivity in one of the syndromes and innate insulin resistance in the other could not be properly ascertained by the selected methodology. Furthermore, results were confusing and even discrepant with the clinical findings. Conclusions The standard homeostatic minimal models could not properly identify or discriminate insulin sensitivity and resistance in subjects with inherently diminished secretion. It is thereby suggested that these models should be used with caution in clinical situations where reduced secretion of the metabolic peptide is found or suspected.

Laron syndrome (LS) is a rare autosomal recessive growth hormone (GH) insensitivity condition due to GH receptor mutation, and with phenotypic features likened to GH deficiency. The incidence of LS in Ecuador is very high and has gained worldwide attention due to its low incidence of cancer and diabetes mellitus. A more recently described population is affected with “Guevara-Rosenbloom syndrome” (GRS). While both groups exhibit severe short stature (-4 to -12 SDS), GRS subjects have normal GH signaling and responses and, unlike LS, have intrauterine growth retardation and early onset type 2 diabetes (T2DM). Since both groups have diminished insulin secretion, there is a unique opportunity to investigate their metabolome under each specific disease. Levels of certain amino acids in insulin-resistant (IR) states such as T2DM are distinct and special attention has been given to the predicting power of branched chain and aromatic amino acids, carnitines, and free fatty acids for IR and T2DM risk assessment. Our aim was to understand the metabolic differences between LS and GRS, which both have diminished insulin secretion but different GH counter-regulation as well as to compare these groups to normal controls. The metabolome of these 3 cohorts was assessed at the following instances: a) At the fasting state, and b) After an oral challenge of 1.5 mg/kg of glucose per kilogram of body weight, administered immediately after the fasting sample was drawn (samples were taken every 30 minutes for 5 hours [5h]). Preliminary results (by ANOVA) show a strong correlation, in the fasting state, between the control and the LS groups with clear discrimination from the GRS cohort, as determined by a heatmap of the top 100 features. Furthermore, the analysis of the 5h profile after the glucose challenge in the 3 groups revealed significant correlations in the levels of amino-acids that have been related to the genesis of IR and T2DM. This work represents the first deep-metabolome analysis in this unique study group. Disclosure V. Rubio: None. C.A. Chamberlain: None. C. Wasserfall: None. J. Guevara-Aguirre: None. A. Guevara: None. A.L. Rosenbloom: None. M.A. Atkinson: None. R.A. Yost: None. T.J. Garrett: None. Funding National Institutes of Health (U24DK097209)

Background We have shown that subjects with Laron syndrome (LS) due to growth hormone receptor deficiency (GHRD) and their relatives have comparable brain structure and function; moreover, the brain of individuals affected with GHRD appears like those of younger people. While the functionally absent growth hormone receptor and the diminished concentrations of the insulin-like growth factor-I have been associated to these findings, the role of the insulin-glucose axis is emerging as an unavoidable consideration when determining the aetiology of these observations. In consequence, we decided to search for the potential and discrete associations between the neurological findings and several parameters of carbohydrate metabolism that might exist in the subjects affected with GHRD. Subjects and methods Individuals affected with GHRD were compared to relative controls. Besides standard measures of anthropometry, body composition and brain characteristics, the elements of the carbohydrate metabolism (CHO), including glucose, insulin, triacylglycerol and the free insulin growth factor binding protein 1 (IGFBP1) concentrations were determined. In addition, the correlations existing between the parameters of CHO and brain characteristics were established. Results Besides the phenotypical characteristics of GHRD subjects, including those of brain structure and function, enhanced insulin sensitivity, and other minor, we observed that the insulin-regulated IGFBP1 had a consistent negative correlation with the main elements of the carbohydrate metabolism only in the individuals affected with the disease, and not in their relatives. Conclusions When compared to their relatives, subjects with GHRD who lack the counter-regulatory effects of GH on the insulin axis, despite their increased risk factor profile due to obesity and increased body fat percentage, have a healthy and younger looking brain associated to an enhanced and coordinated insulin sensitivity. Furthermore, it was observed that in the GHRD subjects IGFBP1 negatively correlates, in a constant and systematic manner, with the main elements of the CHO metabolism. These observations suggest a direct relationship between an efficient insulin sensitivity and a healthy brain.

In Ecuador, a developing South American country, subjects affected with genetic syndromes of severe short stature are commonly referred to as dwarfs or midgets. Furthermore, and because in earlier studies some patients had evidenced mental retardation, such abnormality is assumed to exist in all affected subjects. Herein, we present two discrete instances in which this type of branding occurs. The first is that of individuals with Laron syndrome who are still called ‘dwarfs’ and considered as having a degree of mental retardation despite evidence showing otherwise. A similar problem, that of a girl affected with a genetic syndrome of short stature, which might include mental retardation, is also discussed. Considering that stigmatising is a form of discrimination, it concerns us all. Hence, the use of derogatory terms such as midget, dwarf or cretin, that might unintentionally occur even when delivering the best and most devoted medical care, must be eliminated.

Trypanosoma cruzi is the parasite responsible for Chagas disease (CD), that affects 6-8 million people worldwide. CD treatment is limited to two drugs (benznidazole and nifurtimox). Treatment is mostly effective during the acute phase of the disease (initial two months post-infection), while their efficacy during the chronic phase is controversial. In the absence of treatment, 30% of infected individuals suffer irreversible chronic cardiac and digestive damages, which lead to inability and, in some instances, death. Patients with Laron Syndrome (LS, a form of congenital GH insensitivity) are short in stature with low levels of IGF-1, elevated levels of GH and, surprisingly, are resistant to cancer and diabetes. A cohort of LS patients living in southern Ecuador, where CD is endemic, has been studied by Dr. Jaime Guevara for over 25 years (1). Few, if any, cases of CD have been reported among these patients (Dr. Guevara, personal communications). T. cruzi infection has been shown to directly modulate pituitary hormones such as GH, PRL and glucocorticoids (stress related hormones), leading to immunosuppression and thymic atrophy by depletion of CD4+ CD8+ cells. Previously, rats infected with T. cruzi and treated with GH showed reduced parasitism and less tissue damage compared to controls (2). The purpose of this research is to investigate the in vitro effect of GH during T. cruzi infection, simulating conditions of GH insensitivity. First, we separately treated T. cruzi and the host cells [human cervical cancer cell line (HeLa) and male mouse fibroblast (L-cells)] with relatively low or high levels of GH, IGF-1, PRL, and EGF. Next, we treated the parasite and host cells simultaneously with these hormones. When the parasites were treated alone, T. cruzi responded to exogenous GH (5ng/ml-50ng/ml) by significantly increasing the percentage of amastigotes (less infective form of the parasite). Also, when GH (50ng/ml) were administered to the host cells, T. cruzi infectivity was significantly reduced by 12% (percentage of infection) compared to 20% from untreated conditions. Similarly, both parasite and host cells treated with GH significantly reduced T. cruzi infectivity (10%) compared to untreated conditions (18%). We further treated both cell lines with a combination of GH/IGF-1. Conditions used were as follows: control (no-treatment), moderate levels (5ng/ml GH+150 ng/ml IGF-1), relatively high levels (50ng/ml GH+600ng/ml IGF-1), or levels that would simulate those found in patients with LS(50ng/ml GH+20 ng/ml IGF-1). Of these, the LS concentrations significantly reduced infection in both cell lines (11%) compared to control (16%). Together these results indicate that GH can influence T. cruzi infectivity and that GH, not IGF-1, is mediating the decreased infectivity. Finally, the results suggest that high concentrations of GH, as seen in LS patients, could be protective during T. cruzi infection. 1)Guevara-Aguirre et al., 2011 2) Frare et al., 2010

© The Author(s)., [Background]: Ring chromosome 15 has been associated in previous studies with different clinical characteristic such as cardiac problems, digit and musculoskeletal abnormalities, and mental and motor problems among others. Only 97 clinical cases of ring chromosome 15 syndrome have been reported since 1966 and a common phenotype for these patients has not been established., [Case presentation]: The present case report describes a 15-month-old girl from the Amazon region of Ecuador, of Mestizo ancestry, who after cytogenetic tests showed a 46,XX,r(15) karyotype in more than 70% of metaphases observed. Her parents were healthy and non-related. The pregnancy was complicated and was positive for intrauterine growth retardation. Her birth weight was 1950 g, her length was 43.5 cm, and she had a head circumference of 29.3. In addition to postnatal growth delay, she had scant frontal hair, small eyes, hypertelorism, low-set of ears, flattened nasal bridge, anteverted nostrils, down-turned mouth, three café au lait spots, and delayed dentition., [Conclusions]: Despite the frequency of some phenotypes expressed in the different clinical cases reviewed and the present case, a common phenotype for patients with ring 15 could not be determined and it is restricted to the region of the chromosome lost during the ring formation., Funding for this research was completely managed by the institutions affiliated. Centro de Investigación Genética y Genómica, Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito, Ecuador. Facultad de Ciencias de la Salud, Universidad San Francisco de Quito, Quito, Ecuador. Unidad de Investigación en Biomedicina, Zurita & Zurita Laboratorios, Quito, Ecuador. Servicio de Hematología, Hospital Universitario de Salamanca, Universidad de Salamanca, Salamanca, Spain. Molecular Medicine Unit, Department of Medicine, Biomedical Research Institute of Salamanca (IBSAL), Salamanca, Spain. Institute of Molecular and Cellular Biology of Cancer (IBMCC), University of Salamanca-SACYL-CSIC, Salamanca, Spain.

Ecuadorian subjects with GH receptor deficiency (GHRD) have not developed diabetes, despite obesity.We sought to determine the metabolic associations for this phenomenon.Four studies were carried out: 1) glucose, lipid, adipocytokine concentrations; 2) metabolomics evaluation; 3) metabolic responses to a high-calorie meal; and 4) oral glucose tolerance tests.Clinical Research Institute in Quito, Ecuador.Adults homozygous for the E180 splice mutation of the GH receptor (GHRD) were matched for age, gender, and body mass index with unaffected control relatives (C) as follows: study 1, 27 GHRD and 35 C; study 2, 10 GHRD and 10 C; study 3, seven GHRD and 11 C; and study 4, seven GHRD and seven C.Although GHRD subjects had greater mean percentage body fat than controls, their fasting insulin, 2-hour blood glucose, and triglyceride levels were lower. The indicator of insulin sensitivity, homeostasis model of assessment 2%S, was greater (P.0001), and the indicator of insulin resistance, homeostasis model of assessment 2-IR, was lower (P = .0025). Metabolomic differences between GHRD and control subjects were consistent with their differing insulin sensitivity, including postprandial decreases of branched-chain amino acids that were more pronounced in controls. High molecular weight and total adiponectin concentrations were greater in GHRD (P = .0004 and P = .0128, respectively), and leptin levels were lower (P = .02). Although approximately 65% the weight of controls, GHRD subjects consumed an identical high-calorie meal; nonetheless, their mean glucose concentrations were lower, with mean insulin levels one-third those of controls. Results of the 2-hour oral glucose tolerance test were similar.Measures of insulin sensitivity, adipocytokines, and energy metabolites.Without GH counter-regulation, GHRD is associated with insulin efficiency and obesity. Lower leptin levels, despite higher percentage body fat, suggest that obesity-associated leptin resistance is GH dependent. Elevated adiponectin levels not correlated with percentage body fat indicate that GH signaling is necessary for their typical suppression with obesity.

Along with its inherent properties in growth promotion, cell division and regeneration, growth hormone (GH) exerts a variety of miscellaneous and widespread actions on the human body after binding to its receptor (GHR). Indeed, GH influences the metabolism of carbohydrates, lipids and proteins; shapes body composition, influences cardiovascular profile, quality of life, and induces other direct and indirect physiologic effects. Besides this salutary actions, GH and its derived peptide insulin-like growth factor-I (IGF-I), main product of the GH/GHR interaction, have been implicated in the genesis of diseases such as cancer and insulin-resistant diabetes. The effects of these peptides are difficult to discern in healthy individuals but can be better evaluated in disease states in which their action in target tissues is abnormal. In consequence, we selected acromegaly and Laron syndrome due to GH receptor deficiency (GHRD) as models for excess and absence of GH action, and focused in the role of GH/GHR signaling in the genesis of cancer and diabetes. Considering that malignancy has been linked at epidemiological level to type 2 diabetes and high body mass index, suggesting that hyperinsulinemia is an independent contributor to cancer genesis and progression, we propose that the GH-derived IGF-I is also an independent influence for progression to neoplasia since its absence associates with less DNA damage, diminished mutagenesis and efficient apoptosis. Regarding development of type 2 diabetes, we support the notion that GH, by influencing insulin sensitivity via its counter-regulatory properties on carbohydrate metabolism, is an important contributor for development of this disease.

Specific phenotypic features of subjects affected with genetic syndromes depend on peculiarities of expression of each discrete mutation and on extent of its divergence from normal physiology. In this context, and when studying the GH/IGF-I axis of subjects with two different syndromes that include severe short stature (SSS), we noticed different metabolic phenotypes in each cohort. Subjects with Laron syndrome (LS), who have GH insensitivity (GHI), display obesity, increased body fat, enhanced insulin sensitivity and diminished incidence of diabetes mellitus. Subjects with a new syndrome (NS), who have normal GH signaling, display intrauterine growth retardation (IUGR), normal to slightly elevated body fat content, insulin resistance and early onset type 2 diabetes mellitus (T2DM). In consequence, we were able to observe the clinical consequences of different GH counter-regulation status on carbohydrate metabolism, especially considering that subjects with either syndrome most likely have diminished pancreatic reserve.

Recombinant human insulin-like growth factor-1 (rhIGF-1) treatment studies of growth failure in absence of growth hormone (GH) signaling (GH insensitivity -GHI, Laron syndrome -LS, GH Receptor deficiency -GHRD) have taken place in many locations around the globe. Results from these trials are comparable, and slight differences reported can be attributed to specific circumstances at different research sites. rhIGF-I treatment studies of GHI in Ecuador included various trials performed on children belonging to the largest and only homogeneous cohort of subjects with this condition in the world. All trials were performed by the same team of investigators and, during study periods, subjects received similar nutritional, physical activity and medical advice. Combination of these inherent conditions most likely creates less sources of variability during the research process. Indeed, diagnosis, selection and inclusion of research subjects; methodology used; transport, storage and delivery of study drug; data collection, monitoring and auditing; data analysis, discussion of results, conclusion inferences and reporting, etc., were submitted to the same sources of error. For the above-mentioned reasons, we are hereby mainly covering conclusions derived from rhIGF-I treatment studies of Ecuadorian children whit GHRD due to homozygosity of a splice site mutation occurring at GHR gene, whose unaffected parents were both heterozygous for the same mutation. We also describe studies of rhIGF-I administration in adolescent and adult subjects with GHRD, from the same cohort and with the same genetic anomaly.

Growth hormone receptor deficiency (GHRD) results in short stature, enhanced insulin sensitivity, and low circulating levels of insulin and insulin-like growth factor 1 (IGF-1). Previous studies in mice and humans suggested that GHRD has protective effects against age-related diseases, including cancer and diabetes. Whereas GHRD mice show improved age-dependent cognitive performance, the effect of GHRD on human cognition remains unknown. Using MRI, we compared brain structure, function, and connectivity between 13 people with GHRD and 12 unaffected relatives. We assessed differences in white matter microstructural integrity, hippocampal volume, subregional volumes, and cortical thickness and surface area of selected regions. We also evaluated brain activity at rest and during a hippocampal-dependent pattern separation task. The GHRD group had larger surface areas in several frontal and cingulate regions and showed trends toward larger dentate gyrus and CA1 regions of the hippocampus. They had lower mean diffusivity in the genu of the corpus callosum and the anterior thalamic tracts. The GHRD group showed enhanced cognitive performance and greater task-related activation in frontal, parietal, and hippocampal regions compared with controls. Furthermore, they had greater functional synchronicity of activity between the precuneus and the rest of the default mode network at rest. The results suggest that, compared with controls, GHRD subjects have brain structure and function that are more consistent with those observed in younger adults reported in previous studies. Further investigation may lead to improved understanding of underlying mechanisms and could contribute to the identification of treatments for age-related cognitive deficits.SIGNIFICANCE STATEMENTPeople and mice with growth hormone receptor deficiency (GHRD or Laron syndrome) are protected against age-related diseases including cancer and diabetes. However, in humans, it is unknown whether cognitive function and brain structure are affected by GHRD. Using MRI, we examined cognition in an Ecuadorian population with GHRD and their unaffected relatives. The GHRD group showed better memory performance than their relatives. The differences in brain structure and function that we saw between the two groups were not consistent with variations typically associated with brain deficits. This study contributes to our understanding of the connection between growth genes and brain aging in humans and provides data indicating that GHR inhibition has the potential to protect against age-dependent cognitive decline.

CDKN1C, a cyclin-dependent kinase inhibitor and negative regulator of cellular proliferation, is paternally imprinted and has been shown to regulate β-cell proliferation. CDKN1C mutations are associated with growth disorders, including Beckwith-Wiedemann syndrome and IMAGe syndrome.To investigate the genetic basis for a familial disorder characterized by intrauterine growth restriction, short stature, and early-adulthood-onset diabetes.Genomic DNA samples (15 affected and 26 unaffected from a six-generation pedigree) were analyzed by genome-wide single nucleotide polymorphism arrays, whole exome and Sanger sequencing, and multiplex ligation-dependent probe amplification.Subjects were assessed for height, weight, adrenal gland size, ACTH, diabetes status, and testis volume. Linkage and sequence analyses were performed, and the identified genetic variant was functionally evaluated in reconstitution studies.The pedigree followed a paternally imprinted pattern of inheritance, and genetic linkage analysis identified a single significant 2.6-megabase locus on chromosome 11p15, within the imprinting center region 2. Multiplex ligation-dependent probe amplification did not detect copy number variants or methylation abnormalities. Whole exome sequencing revealed a single novel variant in the proliferating cell nuclear antigen-binding region of CDKN1C (c.842GT, p.R281I) that co-segregated with affected status and, unlike variants found in IMAGe, did not entirely abrogate proliferating cell nuclear antigen binding. Clinical assessments revealed that affected individuals had low testicular volume but normal adrenal function.We report a novel CDKN1C mutation associated with features of IMAGe syndrome, but without adrenal insufficiency or metaphyseal dysplasia, and characterized by early-adulthood-onset diabetes. Our data expand the range of phenotypes observed with CDKN1C defects and suggest that CDKN1C mutations may represent a novel monogenic form of diabetes.

Aging is influenced by endocrine pathways including the growth hormone/insulin-like growth factor-1 (GH/IGF) axis. Mitochondrial function has also been linked to the aging process, but the relevant mitochondrial signals mediating the effects of mitochondria are poorly understood. Humanin is a novel signaling peptide that acts as a potent regulator of cellular stress responses and protects from a variety of in vitro and in vivo toxic and metabolic insults. The circulating levels of humanin decline with age in mice and humans. Here, we demonstrate a negative correlation between the activity of the GH-IGF axis and the levels of humanin, as well as a positive correlation between humanin and lifespan in mouse models with altered GH/IGF-I axis. Long-lived, GH-deficient Ames mice displayed elevated humanin levels, while short-lived GH-transgenic mice have reduced humanin levels. Furthermore, treatment with GH or IGF-I reduced circulating humanin levels in both mice and human subjects. Our results indicate that GH and IGF are potent regulators of humanin levels and that humanin levels correlate with lifespan in mice. This suggests that humanin represents a circulating mitochondrial signal that participates in modulating the aging process, adding a coordinated mitochondrial element to the endocrine regulation of aging.

Laron syndrome (LS) is a genetic disorder caused by mutations in the growth hormone receptor (GHR) gene. The most frequent GHR mutation is E180splice (rs121909360), which was initially found in an inbred population of Spanish descent in Ecuador and subsequently in Israel, Brazil, Chile, and the United States. The aim of the present study is to determine if the E180splice mutation arose from a common origin. We studied 22 patients with LS from Ecuador, Israel (of Moroccan origin), Brazil, Chile, and the United States (of Mexican origin) who were homozygous for the E180splice mutation and compared them to control individuals for markers surrounding the GHR, intragenic polymorphisms, and Y-chromosome STR. An identical haplotype was found in all but one of the subjects carrying the E180splice mutation: D5S665: 150/150; D5S2082: 192/192; D5S2087: 246/246; rs6179 G/G; and rs6180 C/C. One patient differed from the others only at D5S2082 (168/192). This haplotype is rare (~1%) in control individuals and confirmed that the E180splice-associated haplotype was not derived from independent origins but represented recombination from a common ancestor. The analysis of paternal lineage markers showed that 50% belong to haplogroup R1b (found in Portugal and Spain) and 40% to haplogroups J and E (typical in the Middle East and in Eastern European Jews). The germline E180Splice mutation appears to have originated from a single common ancestor. The presence of Y-chromosome markers associated with Sephardic populations in persons harboring the E180splice mutation provides genetic evidence in support of the historical tracking of the exodus of this specific population.

SummaryMice and humans with growth hormone receptor/IGF-1 deficiencies display major reductions in age-related diseases. Because protein restriction reduces GHR-IGF-1 activity, we examined links between protein intake and mortality. Respondents aged 50–65 reporting high protein intake had a 75% increase in overall mortality and a 4-fold increase in cancer death risk during the following 18 years. These associations were either abolished or attenuated if the proteins were plant derived. Conversely, high protein intake was associated with reduced cancer and overall mortality in respondents over 65, but a 5-fold increase in diabetes mortality across all ages. Mouse studies confirmed the effect of high protein intake and GHR-IGF-1 signaling on the incidence and progression of breast and melanoma tumors, but also the detrimental effects of a low protein diet in the very old. These results suggest that low protein intake during middle age followed by moderate to high protein consumption in old adults may optimize healthspan and longevity.

In developed countries, addressing the growing opioid addiction epidemic is focused on preventive measures, developing better overdose-reversal medications and designing newer strategies to treat addiction. Primary prescribers of the therapeutic use of opioids might play a definite role in the aetiology of the epidemics. Developing countries could be affected by similar issues; however, given that no updated statistics are available, it is possible that their populations undergo problems similar to those for which current data is available. Concerns have arisen regarding synthetic opioid tramadol which, given its fast and potent analgesic effects, low cost and easy availability is widely prescribed. A debate remains as to whether tramadol induces addictive effects like those of stronger analogues such as oxycodone or fentanyl. Here we present a case of tramadol dependence in an Ecuadorian patient and find that substance abuse can occur in normal individuals affected by chronic pain, otherwise treatable with standard methods.

Context: The maximum dose of IGF-I recommended for treatment of GH insensitivity is commonly used. Objective: The aim was to test the hypothesis that a lower dose is as effective as a high dose of IGF-I in growth promotion and has fewer deleterious effects. Design and Setting: Subjects were treated for 3 years with regular examinations including bone age and dual energy x-ray absorptiometry and for 1 year with abdominal ultrasound studies at a clinical research institute in Quito, Ecuador. Subjects: The study included 21 subjects ages 3.2–15.9 years with GH insensitivity due to the same splice site mutation on the GH receptor gene. Interventions: Subjects were allocated to receive 120 (n = 14) or 80 (n = 7) μg/kg IGF-I twice daily. Main Outcome Measures: Height velocity, osseous maturation, height SD scores (SDS), body composition, abdominal organ growth, and side effects were assessed. Results: There were no differences in growth velocity or height SDS increment by dosage, and the SDS increase was greater than in other reported series. Osseous maturation over 3 years with the high dose was nearly twice as rapid as with the lower dose (P < .001) and correlated with an increase in percentage body fat (r = .64; P < .001) and with adrenal size increase over 1 year (r = .32; P = .03). The ratio of bone age to height age was lower in the high-dose group after 3 years of treatment (P = .007). Conclusions: The commonly used IGF-I dosage of 120 μg/kg twice a day is excessive in comparison to a dose of 80 μg/kg twice a day, disproportionately accelerating osseous maturation, probably from the combined effects of obesity and inappropriate adrenal growth, thus likely compromising adult height potential. Moreover, the lower dose decreases direct treatment cost by one-third.

Paediatric endocrinology and diabetes is a paediatric specialty with less common conditions and higher cost medicines. Access to medicines for our specialty in low and middle income countries remains limited. We analysed the content of the WHO (children and adults) and of all available national Model Lists of Essential Medicines (EMLs) for Mexico, the Caribbean, Central and South America from a paediatric endocrinology and diabetes standpoint. A master list of medicines deemed necessary in paediatric endocrinology and diabetes was established and compared with the WHO and national EMLs, taking into account the gross national income. The WHO EMLs, which are largely recognised as an international benchmark and drive the content of the national EMLs, included many but not all medicines present on our master list. Interestingly, several national EMLs from richer countries included medicines that were not present in the WHO EMLs. Our analysis suggests that these medicines could be considered by the WHO for inclusion in their EMLs, which may promote the adoption of more medicines by individual countries. We also propose several changes to the WHO and national EMLs that could facilitate access to medicines in our specialty: age cut-off for a child using physical maturity rather than a set age limit; greater standardisation of the formatting of the national EMLs for easier comparison and collaborations between countries; greater emphasis on age-specificity and population-specificity for some medicines; and formatting of the EMLs in a disease-focused manner rather than as individual medicines.

ObjectiveTo describe the clinical and biochemical features, and perform molecular analysis for candidate abnormalities in a novel familial syndrome of intrauterine growth retardation (IUGR), failure of an adolescent growth spurt with proportional adult short stature, minimal subluxation of the 5th metacarpal–phalangeal joint, and adult-onset insulin-resistant diabetes unrelated to obesity or other manifestations of metabolic syndrome (MS).DesignDetailed clinical history, auxological, biochemical, radiological, and molecular studies, including DNA analysis andin vitrostudy of the GH/IGF1 pathway.Materials and methodsTen affected adults from two generations of five related families were studied in detail, and information obtained about nine other likely affected individuals.ResultsHeightZ-scores ranged from −7.3 to −3.8. Unaffected parents of the older generation and frequency of confirmed and suspected instances of the syndrome in the two generations studied is consistent with autosomal recessive inheritance. Insulin resistance was uniformly present in seven subjects tested who were not taking insulin. Diabetes severity did not correlate with overweight. Subjects did not have other typical manifestations of MS such as substantial hyperlipidemia, osteoporosis, or hypertension. No biochemical abnormality in the GH/IGF1 axis or molecular defect was found.ConclusionsWhile the association of IUGR and adult MS, including diabetes, has been well documented, these subjects did not have typical manifestations of MS. Abnormalities in common components that could result in a combination of IUGR, severe postnatal growth, and insulin resistance have been ruled out. A mutation in an unidentified gene may affect intrauterine and postnatal growth, with insulin resistance directly affected or as a result of this growth phenomenon.

Modern day Latin America resulted from the encounter of Europeans with the indigenous peoples of the Americas in 1492, followed by waves of migration from Europe and Africa. As a result, the genomic structure of present day Latin Americans was determined both by the genetic structure of the founding populations and the numbers of migrants from these different populations. Here, we analyzed DNA collected from two well-established communities in Colorado (33 unrelated individuals) and Ecuador (20 unrelated individuals) with a measurable prevalence of the BRCA1 c.185delAG and the GHR c.E180 mutations, respectively, using Affymetrix Genome-wide Human SNP 6.0 arrays to identify their ancestry. These mutations are thought to have been brought to these communities by Sephardic Jewish progenitors. Principal component analysis and clustering methods were employed to determine the genome-wide patterns of continental ancestry within both populations using single nucleotide polymorphisms, complemented by determination of Y-chromosomal and mitochondrial DNA haplotypes. When examining the presumed European component of these two communities, we demonstrate enrichment for Sephardic Jewish ancestry not only for these mutations, but also for other segments as well. Although comparison of both groups to a reference Hispanic/Latino population of Mexicans demonstrated proximity and similarity to other modern day communities derived from a European and Native American two-way admixture, identity-by-descent and Y-chromosome mapping demonstrated signatures of Sephardim in both communities. These findings are consistent with historical accounts of Jewish migration from the realms that comprise modern Spain and Portugal during the Age of Discovery. More importantly, they provide a rationale for the occurrence of mutations typically associated with the Jewish Diaspora in Latin American communities.

Context: Among more than 250 cases of GH insensitivity syndrome (GHIS) reported to date, the largest cohort was identified in southern Ecuador. In the Ecuadorian GHIS cohort, a sense mutation (GAA > GAG) at codon E180 of GH receptor [GHR (E180sp)] results in deletion of codons 181–188. No functional studies of this mutation have been performed, nor have different mutations at codon 180 been reported.Objective: We now report identification of a novel GHR mutation, also within codon E180, in two distantly related GHIS subjects of Inuit origin and provide mechanistic insights into the defects caused by the Inuit and Ecuadorian GHR mutations.Patients: The two Inuit subjects, with heights of −5 sd score and −7 sd score, respectively, had elevated circulating levels of GH but low levels of GH-binding protein, IGF-I, and IGF-binding protein-3.Results: Both Inuit subjects carry the same novel nonsense homozygous GHR mutation at codon E180 (GAA->TAA, E180X). In vitro reconstitution experiments demonstrated that GHR (E180sp), but not GHR (E180X), could be stably expressed. GHR (E180sp), however, could not bind GH and could neither activate signal transducer and activator of transcription-5b nor induce -5b-dependent gene expression on GH treatment. Furthermore, the GHR (E180sp), which has a deletion of eight amino acid residues within the GHR dimerization domain, although retaining the ability to homodimerize, was defective in trafficking to the cell surface.Conclusions: The E180X mutation identified in two Inuit patients resulted in a truncated, unstably expressed GHR variant, whereas the E180 splicing mutation previously identified in the Ecuadorian cohort, affected both GH binding and GHR trafficking and rendered the abnormal GHR nonfunctional.

The aim of this study was to compare the glucose pharmacodynamics after oral spray insulin (Oral-lyn , Generex Biotechnology, Toronto, ON, Canada) and subcutaneous (sc) injection of regular insulin in 10 subjects with type 1 diabetes mellitus (T1DM).Basal therapy was twice-daily insulin glargine. Preprandial (30 min) regular insulin was given for 3 days, followed by 9 days of Oral-lyn, eight to 12 puffs immediately pre- and postprandially. Adjustments for glycemia were made using standard snacks and additional regular insulin or Oral-lyn. Peripheral glucose measurements were self-monitored in duplicate. Serum concentrations of fructosamine and hemoglobin A1c (HbA1c) were determined at the start and the end of the study period.Average glucose concentrations (in mmol/L) for the 3-day regular insulin and 9-day Oral-lyn periods, respectively, were: pre-breakfast (B), 5.06 and 3.89; 1-h post-B, 8.39 and 7.67; post-B, 6.00 and 6.33; pre-lunch (L), 5.50 and 4.72; 1-h post-L, 7.83 and 7.89; 2-h post-L, 5.89 and 6.33; pre-dinner (D), 5.61 and 5.17; 1-h post-D, 7.22 and 7.83; and 2-h post-D, 6.11 and 6.67. Areas under the curve for both treatments were not significantly different (P = 0.6875). Fructosamine (mean +/- SD, 338.7 +/- 77.4 micromol/L and 321.7 +/- 63.4 micromol/L), and HbA1c (mean +/- SD, 7.5 +/- 1.5% and 7.2 +/- 1.2%) did not change significantly.Regular insulin and Oral-lyn had similar glucodynamic effects in subjects with T1DM receiving twice-daily insulin analogue as baseline therapy. Intensive monitoring and timely corrections with additional snacks, additional sc regular insulin, or Oral-lyn puffs resulted in appropriate glycemic control as assessed by individual daily glycemic responses and, especially, normal preprandial glycemia. Protein glycation decreased, but not significantly.

Context & objective: The Ecuadorian GH receptor deficiency (GHRD)/Laron syndrome population is the only large cohort with a single GHR mutation (E180 splice), permitting identification of numerous carrier and noncarrier first-degree relatives, to ascertain effects of heterozygosity on GH-dependent IGF-I and IGFBP-3 concentrations and on growth. Design: First-degree relatives (n = 212) of GHRD patients had specimens taken for IGF-I, IGFBP-3, and GHR genotyping. Normal statured (n = 40) and short statured (n = 40) unrelated controls had measurement of IGF-I, IGFBP-3, and stature. Results: There were no significant differences between heterozygous and homozygous normal relatives in IGF-I or IGFBP-3 standard deviation scores (SDS). Heterozygous relatives had lower mean height SDS than did homozygous normals, but with extensive overlap between genotype groups in both child and adult relatives. Height SDS in general did not relate to IGF-I or IGFBP-3 concentrations. Conclusions: GH-dependent IGF-I and IGFBP-3 secretion is not affected by heterozygosity for the E180 splice mutation that causes GHRD/Laron syndrome in the Ecuadorian population. Heterozygosity is associated with reduction in mean statural SDS, but this is not sufficient to be clinically important and not mediated through measurable differences in circulating IGF-I or IGFBP-3 related to genotype. 2007 Elsevier Ltd. All rights reserved.

In the present pandemics of obesity and insulin resistant diabetes mellitus (DM), the specific contribution of etiological factors such as shifts in nutritional and exercise patterns, genetic and hormonal, is subject of ongoing research. Among the hormonal factors implicated, we selected obesity-driven insulin resistance for further evaluation. It is known that growth hormone (GH) has profound effects on carbohydrate metabolism. In consequence, we compared the effects of the lack of the counter-regulatory effects of GH, in a group of subjects with GH receptor deficiency (GHRD) due to a mutated GH receptor vs. that of their normal relatives. It was found that, despite their obesity, subjects with GHRD, have diminished incidence of diabetes, lower glucose and insulin concentrations, and lower values of indexes indicative of insulin resistance such as HOMA-IR. The GHRD subjects were also capable of appropriately handling glucose or mixed meal loads despite diminished insulin secretion. These observations allow us to suggest that the association of obesity with increased risk for diabetes appears to be dependent on intact growth hormone signaling.

AIM To determine whether recombinant human insulin-like growth factor-I (rhIGF-I) administration to children with low IGF-I and relatively low insulin-like growth factor binding protein-3 (IGFBP3) serum concentrations would result in hypoglycemia. METHODS Eighteen children age 11-19 y with serum levels of IGF-I< -2 SDS and IGFBP3< 0 SDS were randomly assigned to receive rhIGF-I at 80 microg/kg body weight daily (n = 6), 40 microg/kg twice daily (n = 6), or 80 microg/kg twice daily (n = 6). After a 10-d dose escalation and 15 d of treatment at the specified dosage, a 25-h pharmacokinetic/pharmacodynamic profile was obtained, which included 22 blood glucose measurements. Regular meals and snacks were provided. RESULTS No signs or symptoms of hypoglycemia were noted throughout the study. There were no differences in mean blood glucose concentrations among the three dosage groups. The lowest glucose value recorded, 3.44 mmol/l, was 15 min after a morning injection of 80 microg/kg IGF-I, and promptly rose. Although subjects were selected on the basis of low concentrations of IGF-I to represent proposed candidates for rhIGF-I therapy, the mean and range of SDS for height were not different from those of previously studied normal Ecuadorian controls. CONCLUSION In normal individuals with low serum concentrations of IGF-I and relatively low concentrations of IGFBP3, the administration of therapeutic doses of rhIGF-I, while maintaining reasonable food intake, does not result in hypoglycemia.

Objective Proof-of-concept study of evaluation of metabolic effect of novel oral spray insulin (Oralin) formulation at breakfast time in subjects with type 2 diabetes on multiple daily injections. Research design and methods This was an open-label, crossover, randomized study in (n = 23) subjects with type 2 diabetes on multiple daily injections. Subjects received each treatment, in random order, 3 to 7 days apart—a daily dose of SC injection (0.1 u/kg) on one occasion and Oralin spray (100 u) at time 0 min on another occasion. Subjects were given a standard breakfast containing 360 cal (Sustacal liquid meal) 10 min after the dose. Blood samples were taken at regular intervals to measure glucose, insulin, and C-peptide. Results The 30- and 60-min postprandial glucose levels were significantly lowered with Oralin versus that with the injection treatment (146 ± 5 mg/dL Oralin vs 184 ± 7 mg/dL injection at 30 min and 192 ± 6 mg/dL Oralin vs 236 ± 9 mg/dL injection, p < 0.003 at 60 min). The rise in serum insulin levels was significantly higher (Cmax = 98 ± 6 uU/mL for Oralin at 30 min vs 65 ± 3 uU/ml injection, p < 0.001). The reduction in C-peptide was greater in Oralin during the first 60 min (1.38 ± 0.21 ng/mL Oralin vs 1.75 ± 0.38 ng/mL injection, p < 0.001). Conclusions This proof-of-concept study results demonstrated that Oralin could be used as meal insulin in place of mealtime-insulin injections in subjects with type 2 diabetes to regulate the postprandial glucose levels. Copyright © 2004 John Wiley & Sons, Ltd.

The aim of this study was to determine the metabolic effect and the safety of a novel oral insulin spray (Oralin) formulation at breakfast-time in subjects with type 2 diabetes with suboptimal glucose control and maintained on a combination therapy of oral hypoglycemic agents (OHAs). This was an open-label, crossover, randomized study design in subjects (n = 21) with type 2 diabetes (glycated hemoglobin A1c8.0%). Subjects received each of the following treatments, in random order: metformin + glyburide and placebo puffs at time 0 min; or metformin + glyburide and Oralin spray (100 U) at time 0 min. Fifteen minutes later, subjects were given a standard breakfast containing 360 calories [Sustacal (Mead Johnson, Evansville, IN) liquid meal]. Blood samples were taken at regular intervals to measure serum glucose, insulin, and C-peptide. Time-averaged postprandial glucose increments (PPGIs) between 0 and 240 min were calculated for each treatment. Group mean PPGIs to OHAs versus Oralin in combination with OHAs were compared to determine the mean efficacy of the active treatment. The Oralin spray lowered the 2-h postprandial glucose rise significantly in comparison with the OHAs alone. The serum insulin levels were significantly higher with faster onset of action in the Oralin spray treatment when compared with the OHAs treatment. The reductions in C-peptides were also significantly greater in the Oralin arm than in the OHAs treatment. This study results demonstrated that Oralin could be used as meal insulin as an add-on therapy in combination with failing OHAs treatment in subjects with type 2 diabetes to regulate postprandial glucose levels.

Obesity with insulin-resistant diabetes and increased cancer risk is a global problem. We consider the alterations of metabolism attendant on the underlying pathogenic overnutrition and the role of the growth hormone (GH)–IGF-1 axis in this interaction. Obesity-induced insulin resistance is a determinant of diabetes. Excess glucose, and an elevated concentration of insulin acting through its own receptors along with complex interactions with the IGF-1 system, will add extra fuel and fuel signalling for malignant growth and induce anti-apoptotic activities, permitting proliferation of forbidden clones. In Ecuador there are ~100 living adults with lifelong IGF-1 deficiency caused by a GH receptor (GHR) mutation who, despite a high percentage of body fat, have markedly increased insulin sensitivity compared with age- and BMI-matched control relatives, and no instances of diabetes, which is present in 6% of unaffected relatives. Only 1 of 20 deceased individuals with GHR deficiency died of cancer vs 20% of ~1,500 relatives. Fewer DNA breaks and increased apoptosis occurred in cell cultures exposed to oxidant agents following addition of serum from GHR-deficient individuals vs serum from control relatives. These changes were reversible by adding IGF-1 to the serum from the GHR-deficient individuals. The reduction in central regulators of pro-ageing signalling thus appears to be the result of an absence of GHR function. The complex inter-relationship of obesity, diabetes and cancer risk is related to excess insulin and fuel supply, in the presence of heightened anti-apoptosis and uninhibited DNA damage when GHR function is normal.

IGF-I generation tests were developed over 20 yr ago and are currently used in differentiating GH insensitivity (GHI) from other disorders characterized by low serum IGF-I. Nevertheless, generation tests have never been adequately characterized, and insufficient normative data are available. One hundred and ninety-eight subjects [including normal subjects; subjects with GHI, GH deficiency (GHD), and idiopathic short stature (ISS); and heterozygotes for the E180 splice GH receptor mutation] were randomized to self-administration of either a high (0.05 mg/kg x d) or a low (0.025 mg/kg x d) dose of GH for 7 d. After a 2-wk washout period, they received the alternate dose. Samples were collected on d 1, 5, and 8 of each treatment period. In normal individuals, IGF-I generation was GH dependent at all ages, and little advantage was observed in using the higher dose of GH or extending beyond the d 5 sample. Some GHD patients had IGF-I levels, both baseline and stimulated, that overlapped levels in the verified GHI patients. Subjects heterozygous for the E180 GH receptor splice mutation did not show a decreased responsiveness to GH. ISS patients had low-normal IGF-I levels that did not stimulate beyond the baseline normative ranges for age. These data provide the first large scale effort to provide preliminary normative IGF generation data and evaluate the GH sensitivity of patients with GHI, GHD, and ISS.