Impairment of lung volumes and respiratory muscle strength in adult patients with growth hormone deficiency

Vocal Characteristics of Children With Short Stature Before and After Growth Hormone Treatment

OBJECTIVE

To evaluate the vocal characteristics of children with short stature before and 12 months after growth hormone treatment.

MATERIAL AND METHODS

This analytical, observational cohort study included 23 children (age 5-11 years) diagnosed with short stature. Children in the short stature group (SSG) were matched (1:1) for age and sex with children with normal growth (normal stature group; NSG). Participants in the SSG underwent assessments before and 12 months after growth hormone treatment, while those in the NSG underwent the same assessments at baseline and 12 months. The assessments included evaluation of (A) vocal characteristics (history, vocal self-assessment, auditory-perceptual evaluation, and acoustic analysis), (B) anthropometry, (C) bone age, and (D) measurement of insulin-like growth factor-1 (IGF-1) levels.

RESULTS

Children in the SSG had more vocal complaints (P = 0.026) than those in the NSG. The groups were similar in terms of vocal self-assessment and auditory-perceptual evaluation (P = nonsignificant). Results of acoustic analysis were also similar for fundamental frequency (F 0) and perturbation measures (P for both = nonsignificant). F 0 and speech frequency decreased significantly at 12 months in both groups. F1 values were higher at 12 months in the NSG, while F2 values were significantly higher in the baseline evaluation in boys in the SSG. Children in the SSG compared with those in the NSG presented a greater increase in height measurements at 12 months, although the anthropometric means were lower in both evaluations (P < 0.001).

CONCLUSION

Vocal characteristics in children with short stature before and after treatment with growth hormone are comparable to those in children with normal growth.

Growth hormone deficiency with late-onset hypothalamic hypoadrenocorticism associated with respiratory and renal dysfunction: a case report

BACKGROUND

The prevalence of childhood-onset growth hormone (GH) deficiency (GHD) is estimated to be approximately 1 in 5000 or more, with the cause unknown in most cases (idiopathic isolated GHD). However, additional disorders of secretion of other pituitary hormones reportedly develop over time, with a frequency of 2-94% (median, 16%). Furthermore, median times to development of other anterior pituitary hormone deficiencies have been reported to be 6.4-9.4 years. On the other hand, adult patients affected by childhood-onset GHD reportedly develop impaired ventilation function due to reduced lung volumes and respiratory pressures, probably due to reductions in respiratory muscle strength. In addition, GH is known to play a role in stimulating the glomerular filtration rate (GFR), and the estimated GFR (eGFR) is decreased in patients with GHD.

CASE PRESENTATION

This case involved a 65-year-old woman. Her short stature had been identified at around 3 years of age, but no effective treatments had been provided. The patient was mostly amenorrheic, and hair loss became apparent in her late 30s. She developed hyperuricemia, dyslipidemia, and hypertension at 45 years of age. In addition, the patient was diagnosed with hypothyroidism at 50 years of age. At 58 years of age, endocrinological examination showed impaired secretion of thyroid-stimulating hormone, luteinizing hormone/follicle-stimulating hormone, and growth hormone, and magnetic resonance imaging showed an empty sella turcica. However, secretion ability of adrenocorticotropic hormone was retained. At 63 years of age, respiratory function tests confirmed a markedly restricted ventilation disorder (vital capacity, 0.54 L; percentage predicted vital capacity, 26.9%). Renal function had also decreased (eGFR, 25.0 mL/min/1.73 m²). Furthermore, she was diagnosed with hypothalamic secondary hypoadrenocorticism. The patient developed CO₂ narcosis at 65 years of age, and noninvasive positive pressure ventilation was started.

CONCLUSIONS

The rare case of a 65-year-old woman with childhood-onset GHD with panhypopituitarism, including late-onset secondary hypoadrenocorticism in her 60s, associated with severely impaired respiratory function and renal dysfunction, was reported. In GHD patients with risk factors for progression from isolated GHD to combined pituitary hormone deficiency, such as empty sella turcica, lifelong endocrinological monitoring may be important.

Growth hormone replacement therapy improves hypopituitarism-associated hypoxemia in a patient after craniopharyngioma surgery: A case report

RATIONALE

There are some reports about hypoxemia related to hypopituitarism. However, little is known about the relationship between growth hormone deficiency (GHD) and hypoxemia.

PATIENTS CONCERNS

A 23-year-old female presented with severe hypoxemia after the operations of craniopharyngioma. Laboratory tests found that serum growth hormone (GH) levels were extremely low.

DIAGNOSIS

She was diagnosed with growth hormone deficiency-related hypoxemia.

INTERVENTIONS

In addition to oxygenation, low doses of GH replacement therapy was conducted for 3-month.

OUTCOMES

After 3-month r-hGH replacement therapy, hypoxemia was improved significantly and the level of serum GH was elevated.

LESSONS

We've already known that hypopituitarism may induce hypoxemia owing to multiple possible mechanisms according to previous literature. But little is known about growth hormone deficiency-related hypoxemia. Our case shows that GH replacement therapy is an effective treatment, and it's significant to examination the level of GH in serum for hypoxemia patients especially when the cause of hypoxemia is unknown.

Elevated (Pro)renin Receptor Expression Contributes to Maintaining Aerobic Metabolism in Growth Hormone Deficiency

Context

Growth hormone deficiency (GHD) leads to obesity and may induce tissue hypoxia. As (pro)renin receptor [(P)RR] is reported to contribute to the aerobic metabolism by stabilizing pyruvate dehydrogenase (PDH), it may play a substantial role in GHD.

Objective

We aimed to investigate serum soluble (P)RR [s(P)RR] concentration, the origin of s(P)RR, and significance of (P)RR in GHD.

Design, Setting, and Participants

Serum s(P)RR concentration was examined in 72 patients with pituitary diseases, including 32 patients with severe GHD (SGHD) and after GH replacement in 16 SGHD patients. Leptin-deficient ob/ob obese mice were treated with pegvisomant, a GH receptor antagonist, to explore the source of elevated serum s(P)RR in GHD. Adipocytes were cultured with 5% O₂ to examine the effects of hypoxia.

Results

Serum s(P)RR concentration was higher in patients with SGHD than in those without SGHD. Obesity was the important determinant of s(P)RR concentration. Serum s(P)RR concentration significantly decreased after GH replacement in SGHD patients. (P)RR mRNA expression was increased specifically in the adipose tissue (AT) of pegvisomant-treated obese mice compared with that of control obese mice. Hypoxia in cultured adipocytes increased (P)RR expression without affecting the PDH E1 β subunit (PDHB) expression; however, with (P)RR knockdown by small interfering RNA, hypoxia significantly decreased the expression of PDHB.

Conclusion

GHD patients showed increased serum s(P)RR concentration, possibly caused by obesity and hypoxia. (P)RR expression in AT of GHD patients may be elevated to help maintain aerobic metabolism under hypoxia. Thus, the elevated serum s(P)RR level may reflect hypoxia in ATs.

Respiratory failure was improved by growth hormone substitution in a patient with hypopituitarism

A 33-year-old man was referred to the Department of Respiratory Medicine in our hospital due to severe hypercapnic respiratory failure in March 2008. His respiratory function test showed severe restrictive pulmonary dysfunction, and respiratory muscle strength assessed by measuring maximal static expiratory and inspiratory mouth pressures was severely impaired. After non-invasive positive pressure ventilation was started, he was referred to the Endocrinology Department as he was diagnosed as hypopituitarism in his childhood. Pituitary MRI demonstrated pituitary stalk agenesis, and hormonal examination showed that he had severe growth hormone (GH) deficiency. GH replacement therapy was started in August 2008 and his arterial blood gas values and respiratory muscle strength were improved in 6 months. The current case demonstrated that GH deficiency could be a cause of severe respiratory failure.

Aerobic capacity and growth hormone deficiency after traumatic brain injury

CONTEXT

GH deficiency occurs in approximately 20% of all individuals who suffer from a moderate to severe traumatic brain injury.

OBJECTIVE

This study determined whether GH deficiency secondary to traumatic brain injury had an effect on aerobic capacity.

DESIGN

Subjects were screened for GH deficiency by the glucagon stimulation test and performed a maximal treadmill exercise test.

SETTING

Patients were studied in the postacute recovery phase after traumatic brain injury.

PARTICIPANTS

Thirty-five individuals were studied. Groups were formed as follows: normal GH axis, greater than 8 ng/ml response (n = 12); insufficient, GH 3-8 ng/ml response (n = 11); and deficient, less than 3 ng/ml response (n = 12).

INTERVENTION

There was no intervention.

MAIN OUTCOME MEASURE

Aerobic capacity was assessed by measuring expired gases during a graded treadmill exercise test. One-way and two-way ANOVAs were carried out on all peak and submaximal cardiorespiratory variables, respectively. Appropriate post hoc comparisons followed as necessary.

RESULTS

Significantly higher peak oxygen consumption was found in traumatic brain injury subjects with GH normal vs. GH insufficient and deficient [26.4 +/- 6.9, 20.8 +/- 4.6, and 19.7 +/- 5.0, respectively (P < 0.05)]. Submaximal oxygen consumption was significantly higher in the GH normal group. All other variables were statistically similar.

CONCLUSIONS

This study shows that individuals with traumatic brain injury with normal GH secretion have below normal aerobic capacity and those patients who have GH insufficiency/deficiency are further deconditioned. Studies of GH replacement in these subjects should be conducted to assess whether GH therapy can improve cardiorespiratory fitness and prevent secondary disability.

Growth hormone (GH) receptor knockout mice reveal actions of GH in lung development

The presence of growth hormone (GH) and GH receptors (GHRs) in the lung suggests it is an autocrine/paracrine target site for pulmonary GH action and/or an endocrine site of pituitary GH action. Roles for GH in lung growth or pulmonary function are, however, uncertain. The possibility that pituitary and/or pulmonary GH have physiological roles in lung development has therefore been investigated in GHR knockout (KO or -/-) mice, using a proteomics approach to determine if an absence of GH-signaling affects the proteome of the developing lung. More than 600 proteins were detected by 2-DE in the lungs of control [GHR (+/+)] and GHR (-/-) mice at the end of the alveolarization period (at day 14 postnatally). Of these, 39 differed significantly in protein content at the p>0.05 level [6 were of higher abundance in the GHR (-/-) group, 33 were of lower abundance] and 17 differed at the p>0.02 level [5 of higher abundance in the GHR (-/-) group, 12 of lower abundance] and 7 were definitively identified by MS. Vimentin, a protein involved in cellular proliferation, was reduced in content by approximately 75% in the lungs of the GHR (-/-) mice. Three proteins involved in oxidative protection [SH3 domain-binding glutamic acid-rich-like protein, peroxiredoxin 6 (Prdx6), and isocitrate dehydrogenase 1] were also of lower content in the GHR (-/-) lungs (by approximately 88%, 81% and 70%, respectively). Prdx6 is also involved in lipid and surfactant metabolism, as is apolipoprotein A-IV, the lung content of which was reduced by approximately 73% in these mice. Proteasome 26S ATPase subunit 4, a protein involved in the non-lysosomal degradation of intracellular proteins, and electron flavoprotein alpha subunit , involved in intracellular metabolism, were also reduced in content in the lungs of the GHR (-/-) mice (by approximately 70% and 49%, respectively). These results therefore suggest that these proteins are normally dependent upon GH signaling, and that GH is normally involved in early lung growth, oxidative protection, lipid and energy metabolism and in proteasomal activity. These roles may reflect endocrine actions of pituitary GH and/or local autocrine/paracrine actions of GH produced within the lung.

Growth hormone expression in the perinatal and postnatal rat lung

It is now established that the lung is a target site for pituitary growth hormone (GH) action, because pathophysiological states of pituitary GH excess and deficiency are associated with impaired pulmonary function. The onset of lung development and differentiation is, however, before the ontogenic differentiation of pituitary somatotrophs. GH may be involved, nevertheless, in lung development, because it is present in extrapituitary tissues of preimplantation mouse embryos and in the lung buds of embryonic chickens. The possibility that GH may be expressed in the rat lung during fetal and neonatal development, therefore, has been assessed. GH mRNA was detected in the lung, and its 693-bp sequence was identical to that in the pituitary gland. By in situ hybridization, this transcript was found to be abundantly expressed in the lungs of embryonic day (ED) 17 rats in mesenchymal, mucosal epithelial, and smooth muscle cells. This transcript was expressed in neonates until at least day 14 postnatally and was localized to type I and II epithelial cells and to pulmonary tissue macrophages and alveolar macrophages. GH immunoreactivity paralleled GH mRNA cellular localization throughout the time course studied. This immunoreactivity was specific and was lost after antibody preabsorption. The perinatal and postnatal lung is, therefore, an extrapituitary site of GH gene expression during development. Given that the GH receptor is present in the lung from early development, lung GH may have autocrine and/or paracrine roles in lung growth or differentiation or in pulmonary function.

Expression of growth hormone and its receptor in the lungs of embryonic chicks

The lung is well established as being a postnatal target site for growth hormone (GH) action, since pathophysiological states of GH excess and deficiency are both associated with impaired pulmonary function. Pituitary GH is therefore probably involved in normal lung growth or development, although perinatal lung development occurs prior to the differentiation of pituitary somatotrophs and the ontogeny of pituitary GH secretion. The lung itself may, however, be a site of GH production during prenatal development, since a specific GH-response gene (a marker of GH activity) is expressed in the lungs of early chick embryos, in which GH immunoreactivity is widespread in many other peripheral tissues. We have assessed this possibility in embryonic chicks. A 690-bp cDNA, identical in size and nucleotide sequence to the full-length pituitary GH transcript, was amplified by reverse transcription/polymerase chain reaction from total RNA extracted from the lungs of embryos at 11, 13, 15, and 18 days of the 21-day incubation period. This transcript was localized by in situ hybridization to mesenchymal and epithelial cells of the developing lungs, in which specific GH immunoreactivity was similarly located. Intense GH immunoreactivity was also present after embryonic day 15 (ED15) in the smooth muscle surrounding blood vessels in the lung and surrounding the bronchioles. Lung GH immunoreactivity was primarily associated with a 15-kDa protein, rather than the 26-kDa protein in the pituitary gland. After the onset of pituitary GH secretion (at ED17), GH mRNA was barely detectable in the lungs of ED20 embryos, at the start of lung breathing. GH immunoreactivity was, however, still present in some cells in the lungs of ED20 embryos. GH-receptor mRNA and immunoreactivity were also widespread and abundant within the embryonic lung. Lung GH may thus have autocrine or paracrine roles in lung development or in pulmonary function prior to the ontogeny of the pituitary gland and the appearance of GH in peripheral plasma.

Growth hormone (GH) action in the developing lung: Changes in lung proteins after adenoviral GH overexpression

Growth hormone (GH) recently has been shown to be expressed in the neonatal rat lung during alveolarization. The possible functional importance of lung GH in lung function, therefore, has been assessed by determining changes in GH-responsive proteins in the developing rat lung after the overexpression of the GH gene in this tissue. GH overexpression was achieved using an adenovirus that expressed the mouse GH gene. This adenovirus was effective in inducing mouse GH expression in cultured rat lung L2 epithelial cells. It was also shown to be strongly expressed in the alveoli of 14-day-old rat pup lungs 10 days after it was administered by intratracheal injection, during a period of rapid lung development. Expression of the transgene in these pups was accompanied by changes in lung protein concentrations determined by two-dimensional gel electrophoresis and mass spectrometry. The lung concentrations of specific enzymes (nucleotide diphosphate kinase B, Cu/Zn superoxide dismutase, glutathione-S-transferase, and aldehyde reductase-1) were increased by the adenoviral expression of mouse GH, as were the concentrations of beta subunit G-protein calponin 2, beta-5 tubulin, retinoblastoma binding protein 4, and fetuin A. In contrast, the lung concentrations of haptoglobin and major acute phase alpha-1 protein were reduced by adenoviral expression of mouse GH. Although most of these proteins have not previously been identified as GH-responsive proteins, these results demonstrate actions of GH in the rat lung and support the possibility that GH acts as an autocrine/paracrine during early lung development.

Reduction of lung distensibility in acromegaly after suppression of growth hormone hypersecretion

Whether the growth of the lungs in acromegaly is due to alveolar hypertrophy or alveolar hyperplasia is a subject of debate. To discriminate these hypotheses, we compared pulmonary distensibility and diffusing capacity among 11 patients with active acromegaly and 11 matched control subjects, evaluating the response of pulmonary distensibility and diffusing capacity to suppression of growth hormone (GH) hypersecretion. We performed lineal and exponential analyses of quasistatic pressure-volume curves. Patients with active acromegaly had a greater TLC, lung compliance, and shape constant, K, than did normal subjects. We found no significant differences between the study groups in carbon monoxide diffusing capacity or diffusing capacity per unit of alveolar volume. After treatment, patients with inactive acromegaly showed a reduced TLC (6.95 +/- 1.40 [mean +/- SD] L versus 6.35 +/- 1.23 L), reduced lung compliance (3.61 +/- 0.90 L/kPa versus 2.36 +/- 0.79 L/ kPa), reduced K coefficient (2.62 +/- 0.65 kPa(-)(1) versus 1.35 +/- 0.40 kPa(-)(1)), and increased maximal recoil pressure (1.74 +/- 0.38 kPa versus 2.28 +/- 0.25 kPa). We conclude that the increased lung distensibility with normal diffusion capacity demonstrated in patients with active acromegaly, which was partly reversible after suppression of GH hypersecretion, suggests that lung growth in acromegaly may result from an increase in alveolar size.

Growth hormone therapy in adults

The importance of growth hormone (GH) deficiency in adults became evident 10 to 15 years ago, when the first clinical studies on GH replacement therapy in adults were published. Since then, a number of studies have been reported showing that GH replacement therapy can improve this condition. Adult GH deficiency (GHD) is now recognized as a specific clinical syndrome and the first reports of long-term use of GH (up to 10 years) are now being published. The aim of this paper was to review the accumulated data on the various clinical aspects of adult GHD.

Effect of low-dosage recombinant human growth hormone therapy on pulmonary function in hypopituitary patients with adult-onset growth hormone deficiency

An impairment of the pulmonary function has been described in adult patients with childhood-onset growth hormone deficiency (GHD). We examined forced vital capacity (FVC), forced expiratory volume (FEV1), total lung capacity (TLC), functional residual capacity (FRC), residual volume (VR) and the index of inspiratory strength, middle tidal volume and tidal inspiratory time ratio (TV/I), in 29 patients with adult-onset GHD. Data were compared with those obtained in 46 healthy control subjects. Only the FEV1/FVC ratio was statistically different (p = 0.04) between the two groups of subjects. In a group of 15 GHD patients low dosages (0.5-1 IU/day s.c., bedtime) of recombinant human GH (rh-GH; n. = 8 subjects) or placebo (n. = 7) were given at random for a 6-month period. A significant increase in IGF-I levels was noted in the rh-GH-treated group (p = 0.04) but not in the placebo group. After the 6-month period no statistically significant changes in pulmonary function were found between the rh-GH-treated and placebo-treated GHD patients. This study shows that adult-onset GHD patients suffer from minimal impairment of pulmonary function. Low rh-GH dosages able to induce an increase in IGF-I levels do not improve pulmonary function. The effect of rh-GH on respiratory muscle strength could be related to the age at which GHD diagnosis is made, or induced only by high rh-GH dosages given for a long time.