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PURPOSE: In surgical practice during endoscopic endonasal approach (EEA), Growth Hormone-secreting Pituitary Neuroendocrine Tumors (GH-secreting PitNET) patients show morphologic differences in the nasal cavities and sinuses, leading to a narrower surgical field and a carotid prominence and potentially increasing the complexity of the surgical and the risk of complications. The aim of the study is to evaluate the anatomical differences of the sphenoid sinus between patients with GH-secreting PitNETs and patients with non-functioning Pituitary Neuroendocrine Tumors (NF-PitNET) underwent EEA. METHODS: This is a monocentric retrospective study conducted at author's institution. The minimum intercarotid distance (ICS), the largest diameter of the sphenoid sinus (DSS) and the distance between vomer and clivus (VCD) were collected and compared. Presence, localization and course of intersphenoid sinus septum (ISS) were also evaluated. RESULTS: 100 consecutive patients were identified: 57 males (57%) and 43 females (43%), with a mean age of 55 years. 60 patients had NF-PitNET (60%) and 40 had GH-secreting PitNET (40%). GH-secreting PitNET group presented inferior values of ICD (16.8±3.94 mm vs. 20.4±3.94 mm, p<0.001), DSS (32.5±9.81 mm vs. 38.6±11.03 mm, p=0.006) and VCD (25.5±6.96 mm vs. 29.6±8.47 mm, p=0.012) compared to NF-PitNET group. ISS showed no differences between the two groups. CONCLUSION: ICD, DSS and VCD resulted smaller in acromegalic patients, confirming that patients with GH-secreting PitNETs have a narrower surgical field. A meticulous anatomical preoperative planning and neuronavigation are important to recognize the sphenoid anatomical landmarks in order to reduce the risk of complications, especially in acromegalic patients.
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Chemotherapy treatment against pancreatic ductal adenocarcinoma (PDAC) is thwarted by tumoral activation of multiple therapy resistance pathways. The growth hormone (GH)-GH receptor (GHR) pair is a covert driver of multimodal therapy resistance in cancer and is overexpressed in PDAC tumors, yet the therapeutic potential of targeting the same has not been explored. Here, we report that GHR expression is a negative prognostic factor in patients with PDAC. Combinations of gemcitabine with different GHR antagonists (GHRAs) markedly improve therapeutic outcomes in nude mice xenografts. Employing cultured cells, mouse xenografts, and analyses of the human PDAC transcriptome, we identified that attenuation of the multidrug transporter and epithelial-to-mesenchymal transition programs in the tumors underlie the observed augmentation of chemotherapy efficacy by GHRAs. Moreover, in human PDAC patients, GHR expression strongly correlates with a gene signature of tumor promotion and immune evasion, which corroborate with that in syngeneic tumors in wild-type vs. GH transgenic mice. Overall, we found that GH action in PDAC promoted a therapy-refractory gene signature in vivo, which can be effectively attenuated by GHR antagonism. Our results collectively present a proof of concept toward considering GHR antagonists to improve chemotherapeutic outcomes in the highly chemoresistant PDAC.
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Carcinoma Ductal Pancreático , Desoxicitidina , Gencitabina , Neoplasias Pancreáticas , Receptores da Somatotropina , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Humanos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Camundongos , Receptores da Somatotropina/metabolismo , Receptores da Somatotropina/antagonistas & inibidores , Receptores da Somatotropina/genética , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Linhagem Celular Tumoral , Camundongos Nus , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , FemininoRESUMO
Background: Pituitary neuroendocrine tumors (PitNETs) are predominantly benign, though a minority may exhibit invasive tendencies. A diagnosis of metastatic PitNETs, in the absence of malignant histology, hinges on the identification of craniospinal and/or systemic metastases. Only a minority of PitNETs exhibit intracranial seeding. Notably, craniotomy for PitNETs excision is a prominent catalyst for iatrogenic seeding. Case Description: This article presented a compelling case that 15 years following craniotomy for the resection of a somatotroph PitNET, a lesion emerged at the left frontal base within the ethmoid sinus. Subsequent post-operative pathology unveiled a mature plurihormonal pituitary specific transcription factor 1 (PIT-1)-lineage PitNET. Growth hormone (GH) levels decreased significantly from 22.8 ng/mL pre-operation to 2 ng/mL post-operative, and concurrently, prolactin (PRL) levels decreased from 26.7 ng/mL pre-operation to 4.5 ng/mL post-operation. Furthermore, in the follow-up examination conducted 5 months after the operation, both GH and PRL levels were found to be within the normal range for the patient. This robustly suggested that the initial surgical procedure played a key role in the development of the lesion. Conclusions: This underscores the paramount significance of strictly adhering to the non-tumor removal during craniotomy for PitNETs excision. Regardless of apparent complete resection on imaging, it remains imperative to conduct routine follow-up evaluations, encompassing both imaging studies and hormone level assessments.
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Somatic growth in vertebrates is mainly controlled by the growth hormone (GH)/insulin-like growth factor I (IGF-I) axis. The role of epigenetic mechanisms in regulating this axis in fish is far from being understood. This work aimed to optimize and evaluate the use of short-term culture of pituitary and liver explants from a farmed fish, the gilthead seabream Sparus aurata, for studying epigenetic mechanisms involved in GH/IGF-I axis regulation. Our results on viability, structure, proliferation, and functionality of explants support their use in short-term assays. Pituitary explants showed no variation in gh expression after exposure to the DNA methylation inhibitor decitabine (5-Aza-2'-deoxycytidine; DAC), despite responding to DAC by changing dnmt3bb and tet1 expression, and TET activity, producing an increase in overall DNA hydroxymethylation. Conversely, in liver explants, DAC had no effects on dnmt s and tet s expression or activity, but modified the expression of genes from the GH-IGF-I axis. In particular, the expression of igfbp2a was increased and that of igfbp4, ghri and ghrii was decreased by DAC as well as by genistein, which is suggestive of impaired growth. While incubation of liver explants with S-adenosylmethionine (SAM) produced no clear effects, it is proposed that nutrients must ensure the methylation milieu within the liver in the fish to sustain proper growth, which need further in vivo verification. Pituitary and liver explants from S. aurata can be further used as described herein for the screening of inhibitors or activators of epigenetic regulators, as well as for assessing epigenetic mechanisms behind GH-IGF-I variation in farmed fish.
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INTRODUCTION: Excess growth hormone (GH) secretion in acromegaly has a major impact on mineral balance and serum phosphate levels. However, the clinical utilization of serum phosphate levels as a marker for long-term disease outcomes in acromegaly has not been evaluated. METHODS: This is a retrospective study of patients with acromegaly who were followed in a tertiary center. Data were retrieved on patient characteristics, endocrine and biochemical evaluation, and tumor parameters. Comparisons were performed by measuring baseline phosphate levels and conducting correlation analysis and multivariable logistic regression. RESULTS: Sixty-one patients were followed for 4.5 years (range 1-21). Patients with hyperphosphatemia (> 4.5 mg/dl) at baseline had larger adenomas (15.0 mm [8.0, 47.0] vs. 10.0 mm [3.0, 24.0], p = 0.001), a rate chance of invasive adenoma (16 [80.0%] vs. 14 [46.7%], p = 0.02), and lower serum cortisol levels (226.0 nmol/l [27.6, 516.0] vs. 294.0 nmol/l [32.0, 610.0], p = 0.02). Baseline serum phosphate levels positively correlated with IGF-1 levels (r = 0.43, p = 0.003) and negatively correlated with morning plasma cortisol levels (r = -0.46, p = 0.002). Regarding long-term impact, baseline phosphate levels correlated with the number of pituitary axes involved 6 months after diagnosis (r-0.34, p = 0.01). In multivariable analysis, baseline plasma phosphate levels were independently associated with risk for disease progression/recurrence (odds ratio [OR] 9.66, 95% confidence interval [CI] 1.5, 105.9, p = 0.03) and for invasive adenoma (OR 6.21, 95% CI 1.6, 28.7, p = 0.01). CONCLUSION: Elevated pretreatment serum phosphate levels are associated with a greater risk of disease persistence and recurrence and with altered pituitary function in patients with acromegaly.
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Growth hormone (GH) is a pituitary protein that exerts pleiotropic roles in vertebrates. The mechanisms regulating GH synthesis and secretion are finely controlled by hypothalamic neuropeptides and other factors. These processes have been considerably studied in mammals but are still poorly understood in other groups. To better understand the pituitary GH regulation during vertebrate phylogeny, we compared the effects of incubating several peptides on cultures of ex-vivo pituitary fragments obtained from representative specimens of reptiles (iguana), birds (chicken) and mammals (rat). The peptides used were: growth hormone-releasing hormone (GHRH), thyrotropin-releasing hormone (TRH), pituitary adenylate cyclase-activating polypeptide (PACAP), ghrelin, gonadotropin-releasing hormone (GnRH), and somatostatin (SST). In rat pituitary cultures, GH secretion was stimulated by GHRH and TRH, while gh mRNA expression was increased by GHRH and PACAP. In the case of chicken pituitaries, GH release was promoted by GHRH, ghrelin, PACAP, and GnRH, although the latter two had a dual effect since at a shorter incubation time they decreased GH secretion; in turn, gh mRNA expression was significantly stimulated by TRH, PACAP, and GnRH. The most intense effects were observed in iguana pituitary cultures, where GH secretion was significantly augmented by GHRH, PACAP, TRH, ghrelin, and GnRH; while gh mRNA expression was stimulated by GHRH, TRH, and PACAP, but inhibited by ghrelin and SST. Also, in the three species, SST was able to block the GHRH-stimulated GH release. Furthermore, it was found that the expression of Pou1f1 mRNA was increased with greater potency by GHRH and PACAP in the iguana, than in chicken or rat pituitary cultures. Additionally, in-silico analysis of the gh gene promoter structures in the three species showed that the reptilian promoter has more Pit-1 consensus binding sites than their avian and mammalian counterparts. Taken together, results demonstrate that pituitary peptide-mediated GH regulatory mechanisms are differentially controlled along vertebrate evolution.
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Currently, the main α-amylase family GH13 has been divided into 47 subfamilies in CAZy, with new subfamilies regularly emerging. The present in silico study was performed to highlight the groups, represented by the maltogenic amylase from Thermotoga neapolitana and the α-amylase from Haloarcula japonica, which are worth of creating their own new GH13 subfamilies. This enlarges functional annotation and thus allows more precise prediction of the function of putative proteins. Interestingly, those two share certain sequence features, e.g. the highly conserved cysteine in the second conserved sequence region (CSR-II) directly preceding the catalytic nucleophile, or the well-preserved GQ character of the end of CSR-VII. On the other hand, the two groups bear also specific and highly conserved positions that distinguish them not only from each other but also from representatives of remaining GH13 subfamilies established so far. For the T. neapolitana maltogenic amylase group, it is the stretch of residues at the end of CSR-V highly conserved as L-[DN]. The H. japonica α-amylase group can be characterized by a highly conserved [WY]-[GA] sequence at the end of CSR-II. Other specific sequence features include an almost fully conserved aspartic acid located directly preceding the general acid/base in CSR-III or well-preserved glutamic acid in CSR-IV. The assumption that these two groups represent two mutually related, but simultaneously independent GH13 subfamilies has been supported by phylogenetic analysis as well as by comparison of tertiary structures. The main α-amylase family GH13 has thus been expanded by two novel subfamilies GH13_48 and GH13_49. KEY POINTS: ⢠In silico analysis of two groups of family GH13 members with characterized representatives ⢠Identification of certain common, but also some specific sequence features in seven CSRs ⢠Creation of two novel subfamilies-GH13_48 and GH13_49 within the CAZy database.
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Filogenia , alfa-Amilases , alfa-Amilases/genética , alfa-Amilases/metabolismo , alfa-Amilases/química , Sequência de Aminoácidos , Sequência Conservada , Alinhamento de SequênciaRESUMO
Responsible use of natural resources and waste reduction are key concepts in bioeconomy. This study demonstrates that agro-food derived-biomasses from the Italian food industry, such as crude glycerol and cheese whey permeate (CWP), can be combined in a high-density fed-batch culture to produce a recombinant ß-galactosidase from Marinomonas sp. ef1 (M-ßGal). In a small-scale process (1.5 L) using 250 mL of crude glycerol and 300 mL of lactose-rich CWP, approximately 2000 kU of recombinant M-ßGal were successfully produced along with 30 g of galactose accumulated in the culture medium. The purified M-ßGal exhibited high hydrolysis efficiency in lactose-rich matrices, with hydrolysis yields of 82 % in skimmed milk at 4 °C and 94 % in CWP at 50 °C, highlighting its biotechnological potential. This approach demonstrates the effective use of crude glycerol and CWP in sustainable and cost-effective high-density Escherichia coli cultures, potentially applicable to recombinant production of various proteins.
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Biotecnologia , Queijo , Escherichia coli , Glicerol , Soro do Leite , beta-Galactosidase , Glicerol/metabolismo , beta-Galactosidase/metabolismo , Escherichia coli/metabolismo , Biotecnologia/métodos , Proteínas Recombinantes/metabolismo , Hidrólise , Técnicas de Cultura Celular por Lotes , Lactose/metabolismoRESUMO
Severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN) is a bone dysplasia caused by a pathogenic variant of fibroblast growth factor receptor 3 (FGFR3). Pathogenic variants in FGFR3 also cause thanatophoric dysplasia (TD) and achondroplasia. Although the findings of SADDAN and TD during the fetal and neonatal periods are similar, they differ in their long-term prognoses. We conducted FGFR3 analysis in one male patient because of the difficulty in differentiating SADDAN from TD during the neonatal period. We found that the patient had a pathogenic variant, p. Lys650Met, which was similar to that previously reported in patients with SADDAN. Reports on long-term survival in patient with SADDAN are scarce, and there have been no reports of treatment with GH. We administered GH therapy for a markedly short stature. After treatment, his height increased by 4 cm each year for 4 years, the frequency of hospitalizations due to respiratory failure decreased, and the health improved. FGFR3 analysis is useful for diagnosing SADDAN during the early neonatal period. GH therapy may have contributed to the patient's long-term survival.
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Adipsic hypernatremia is typically caused by congenital dysplasia of the hypothalamus and pituitary or brain tumors. However, cases of adipsic hypernatremia without underlying organic abnormalities are rare, and some cases have been reported to be complicated by hypothalamic-pituitary dysfunction. The patient in this case was a 9-yr-old boy who was referred to our hospital because of hypernatremia. His growth chart revealed that he had rapidly become obese since infancy, with growth retardation since the age of seven. His hands and feet were very cold, and he had erythema on his abdomen, indicating possible autonomic dysregulation due to hypothalamic dysfunction. Several hormone load tests showed severe GH deficiency (GHD) and marked hyperprolactinemia (peak: 302.8 ng/mL). Magnetic resonance imaging revealed no organic abnormalities in the hypothalamus and pituitary gland. GH replacement therapy was initiated. Although his growth rate improved, obesity persisted. To the best of our knowledge, this is the first report of adipsic hypernatremia without organic intracranial abnormalities that was treated with GH. Moreover, the patient's prolactin levels were higher than those reported in previous studies. In conclusion, adipsic hypernatremia requires the evaluation of pituitary function and appropriate therapeutic interventions.
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Diisononyl phthalate (DiNP) has been used to replace bis(2-ethylhexyl) phthalate (DEHP) and is frequently found in the environment and humans. DiNP is reported for its anti-androgenic activity; however, little is known about its effects on thyroid function and neurodevelopment. In the present study, the thyroid disruption and neurobehavioral alteration potential of DiNP and its major metabolites were assessed in a rat pituitary carcinoma cell line (GH3) and embryo-larval zebrafish (Danio rerio). In GH3 cells, exposure to DiNP and its metabolites not only increased proliferation but also induced transcriptional changes in several target genes, which were different from those observed with DEHP exposure. In larval fish, a 5-day exposure to DiNP caused significant increases in thyroid hormone levels, following a similar pattern to that reported for DEHP exposure. Following exposure to DiNP, the activity of the larval fish decreased, and neurodevelopment-related genes, such as c-fos, elavl3, and mbp, were down-regulated. These changes are generally similar to those observed for DEHP. Up-regulation of gap43 and down-regulation of elavl3 gene, which are important for both thyroid hormone production and neurodevelopment, respectively, support the potential for both thyroid and behavioral disruption of DiNP. Overall, these results emphasize the need to consider the adverse thyroid and neurodevelopmental effects in developing regulations for DEHP-replacing phthalates.
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Larva , Ácidos Ftálicos , Glândula Tireoide , Hormônios Tireóideos , Peixe-Zebra , Animais , Larva/efeitos dos fármacos , Glândula Tireoide/efeitos dos fármacos , Hormônios Tireóideos/metabolismo , Ratos , Ácidos Ftálicos/toxicidade , Poluentes Químicos da Água/toxicidade , Linhagem Celular Tumoral , Dietilexilftalato/toxicidade , Comportamento Animal/efeitos dos fármacos , Disruptores Endócrinos/toxicidadeRESUMO
Objective: Individuals with hypopituitarism (HPs) have an increased risk of developing non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) due to growth hormone deficiency (GHD). We aimed to investigate the possible mechanisms underlying the relationship between GHD and NAFLD using proteomic and metabolomic insights. Methods: Serum metabolic alternations were assessed in male HPs using untargeted metabolomics. A rat model of HP was established through hypophysectomy, followed by recombinant human growth hormone (rhGH) intervention. The mechanisms underlying GHD-mediated NAFLD were elucidated through the application of label-free proteomics and phosphorylation proteomics. Results: Metabolomic analysis revealed that biomarkers of mitochondrial dysfunction and oxidative stress, such as alanine, lactate, and creatine, were significantly elevated in HPs compared to age-matched controls. In rats, hypophysectomy led to marked hepatic steatosis, lipid peroxidation, and reduced glutathione (GSH), which were subsequently modulated by rhGH replacement. Proteomic analysis identified cytochrome P450s, mitochondrial translation elongation, and PPARA activating genes as the major distinguishing pathways in hypophysectomized rats. The processes of fatty acid transport, synthesis, oxidation, and NADP metabolism were tightly described. An enhanced regulation of peroxisome ß-oxidation and ω-oxidation, together with a decreased NADPH regeneration, may exacerbate oxidative stress. Phosphoproteome data showed downregulation of JAK2-STAT5B and upregulation of mTOR signaling pathway. Conclusions: This study identified proteo-metabolomic signatures associated with the development of NAFLD in pituitary GHD. Evidence was found of oxidative stress imbalance resulting from abnormal fatty acid oxidation and NADPH regeneration, highlighting the role of GH deficiency in the development of NAFLD.
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Hipopituitarismo , Metabolômica , Hepatopatia Gordurosa não Alcoólica , Estresse Oxidativo , Proteômica , Animais , Masculino , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Ratos , Hipopituitarismo/metabolismo , Hipopituitarismo/etiologia , Ratos Sprague-Dawley , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/metabolismo , HumanosRESUMO
Human cytomegalovirus (HCMV) is a ß-herpesvirus that poses severe disease risk for immunocompromised patients who experience primary infection or reactivation. Development and optimization of safe and effective anti-HCMV therapeutics is of urgent necessity for the prevention and treatment of HCMV-associated diseases in diverse populations. The use of neutralizing monoclonal antibodies (mAbs) to limit HCMV infection poses a promising therapeutic strategy, as anti-HCMV mAbs largely inhibit infection by targeting virion glycoprotein complexes. In contrast, the small-molecule compounds currently approved for patients (e.g., ganciclovir, letermovir, and maribavir) target later stages of the HCMV life cycle. Here, we present a broadly neutralizing human mAb, designated 1C10, elicited from a VelocImmune mouse immunized with infectious HCMV particles. Clone 1C10 neutralizes infection after virion binding to cells by targeting gH/gL envelope complexes and potently reduces infection of diverse HCMV strains in fibroblast, trophoblast, and epithelial cells. Antibody competition assays found that 1C10 recognizes a region of gH associated with broad neutralization and binds to soluble pentamer in the low nanomolar range. Importantly, 1C10 treatment significantly reduced virus proliferation in both fibroblast and epithelial cells. Further, the combination treatment of mAb 1C10 with ganciclovir reduced HCMV infection and proliferation in a synergistic manner. This work characterizes a neutralizing human mAb for potential use as a HCMV treatment, as well as a possible therapeutic strategy utilizing combination-based treatments targeting disparate steps of the viral life cycle. Collectively, the findings support an antibody-based therapy to effectively treat patients at risk for HCMV-associated diseases. IMPORTANCE: Human cytomegalovirus is a herpesvirus that infects a large proportion of the population and can cause significant disease in diverse patient populations whose immune systems are suppressed or compromised. The development and optimization of safe anti-HCMV therapeutics, especially those that have viral targets and inhibition mechanisms different from current HCMV treatments, are of urgent necessity to better public health. Human monoclonal antibodies (mAbs) that prevent HCMV entry of cells were identified by immunizing transgenic mice and screened for broad and effective neutralization capability. Here, we describe one such mAb, which was found to target gH/gL envelope complexes and effectively limit HCMV infection and dissemination. Further, administration of the antibody in combination with the antiviral drug ganciclovir inhibited HCMV in a synergistic manner, highlighting this approach and the use of anti-HCMV mAbs more broadly, as a potential therapeutic strategy for the treatment of diverse patient populations.
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Anticorpos Monoclonais , Anticorpos Antivirais , Infecções por Citomegalovirus , Citomegalovirus , Camundongos Transgênicos , Proteínas do Envelope Viral , Animais , Humanos , Citomegalovirus/imunologia , Citomegalovirus/efeitos dos fármacos , Camundongos , Anticorpos Antivirais/imunologia , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/prevenção & controle , Infecções por Citomegalovirus/virologia , Proteínas do Envelope Viral/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Vírion/imunologia , Fibroblastos/virologia , Replicação Viral/efeitos dos fármacos , Anticorpos Amplamente Neutralizantes/imunologia , Antivirais/farmacologia , ImunizaçãoRESUMO
Glycoside hydrolase family 6 cellobiohydrolase (GH6 CBH) is a group of cellulases capable of hydrolyzing crystalline cellulose. However, the synergistic reaction of GH6 CBH with other cellulases is hindered by its relatively low thermotolerance. We previously obtained a thermotolerant double mutant, C240S/C393S, of GH6 CBH from the basidiomycete Phanerochaete chrysosporium (PcCel6A) by replacing the two free cysteine (Cys) residues, C240 and C393, with serine (Yamaguchi et al., J Appl Glycosci. 2020; 67;79-86). In the accompanying paper (Part I; Yamaguchi et al., J Appl Glycosci. 2024; 71: 55-62), we measured the temperature dependence of the activity and folding of C240S/C393S and its single mutants, C240S and C393S, and found that replacement of C393 was the major contributor to the increased thermotolerance of C240S/C393S. Here, in order to investigate the mechanism involved, we crystallized the wild-type and the mutant enzymes and compared their X-ray crystal structures. The overall structures of the wild-type and the three mutant enzymes were similar. However, C240S/C393S had the lowest relative B-factor at both the N-terminal loop (residues 172-177) and the C-terminal loop (residues 390-425). This result suggests that reduced structural fluctuation of the substrate-enclosing loops, possibly due to stronger hydrogen bonding involving C393, could account for the increased thermotolerance of C240S/C393S.
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Cellobiohydrolase (CBH), belonging to glycoside hydrolase family 6 (GH6), plays an essential role in cellulose saccharification, but its low thermotolerance presents a challenge in improving the reaction efficiency. Based on a report that chimeric CBH II (GH6) engineered to remove non-disulfide-bonded free Cys shows increased thermotolerance, we previously mutated the two free Cys residues to Ser in GH6 CBH from the basidiomycete Phanerochaete chrysosporium (PcCel6A) and obtained a thermotolerant double mutant, C240S/C393S (Yamaguchi et al., J. Appl. Glycosci. 2020; 67: 79-86). Here, characterization of the double mutant revealed that its activity towards both amorphous and crystalline cellulose was higher than that of the wild-type enzyme at elevated temperature, suggesting that the catalytic domain is the major contributor to the increased thermotolerance. To investigate the role of each free Cys residue, we prepared both single mutants, C240S and C393S, of the catalytic domain of PcCel6A and examined their residual activity at high temperature and the temperature-dependent changes of folding by means of circular dichroism measurements and thermal shift assay. The results indicate that the C393S mutation is the main contributor to both the increased thermotolerance of C240S/C393S and the increased activity of the catalytic domain at high temperature.
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CONTEXT: The 2019 AACE guidelines suggested peak GH-cutoffs to glucagon test (GST) of ≤3 µg/L and ≤1 µg/L in the diagnosis of permanent GH deficiency (GHD) during the transition phase. OBJECTIVE: Aim of the study was to evaluate the accuracy of GST compared to insulin tolerance test (ITT) in the definition of GHD at adult height achievement. PATIENTS AND METHODS: Ninety-seven subjects with childhood-onset GHD (median age, 17.39 years) underwent ITT, GST and IGF-1 testing; 44 subjects were idiopathic (isolated GHD), 35 moderate organic GHD (0-2 hormone deficiencies-HDs) and 18 severe organic GHD (≥3 HDs). RESULTS: Bland and Altman analysis showed a high consistency of GH peak measures after ITT and GST. Receiver operating characteristic analysis-ROC- identified 7.3 µg/L as the optimal GH peak cutoff to GST (95% CI 4.15-8.91; sensitivity 95.7%, specificity 88.2%, positive predictive value-PPV-88.0%, negative predictive value-NPV-95.7%), able to correctly classify 91.8% of the entire cohort while 5.8 µg/L was the best GH peak cutoff able to correctly classify 91.4% of moderate organic GHD patients (95% CI 3.16-7.39; sensitivity 96.0%, specificity 80.0%, PPV 92.3%, NPV 88.9%). Patients with ≥3HDs showed a GH peak <5µg/L at ITT and <5.8µg/L at GST but one. The optimal cutoff for IGF1 was -1.4 SDS (95% CI -1.94-0.77; sensitivity 75%, specificity 94%, PPV 91.7%, NPV 81.0%) that correctly classified 85.1% of the study population. CONCLUSIONS: A GH peak to GST <5.8 µg/L represents an accurate diagnostic cutoff for young adults with childhood-onset GHD and high pre-test probability of permanent GHD.
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Acromegaly is a rare endocrine disorder caused by hypersecretion of growth hormone (GH) from a pituitary adenoma. Elevated GH levels stimulate excess production of insulin-like growth factor 1 (IGF-1) which leads to the insidious onset of clinical manifestations. The most common primary central nervous system (CNS) tumors, meningiomas originate from the arachnoid layer of the meninges and are typically benign and slow-growing. Meningiomas are over twice as common in women as in men, with age-adjusted incidence (per 100,000 individuals) of 10.66 and 4.75, respectively. Several reports describe co-occurrence of meningiomas and acromegaly. We aimed to determine whether patients with acromegaly are at elevated risk for meningioma. Investigation of the literature showed that co-occurrence of a pituitary adenoma and a meningioma is a rare phenomenon, and the majority of cases involve GH-secreting adenomas. To the best of our knowledge, a systematic review examining the association between meningiomas and elevated GH levels (due to GH-secreting adenomas in acromegaly or exposure to exogenous GH) has never been conducted. The nature of the observed coexistence between acromegaly and meningioma -whether it reflects causation or mere co-association -is unclear, as is the pathophysiologic etiology. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022376998.
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Acromegalia , Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/complicações , Meningioma/etiologia , Meningioma/patologia , Meningioma/epidemiologia , Acromegalia/complicações , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/epidemiologia , Neoplasias Meníngeas/patologia , Hormônio do Crescimento Humano/metabolismo , Hormônio do Crescimento Humano/sangue , Fatores de Risco , Adenoma/complicações , Adenoma/metabolismo , Adenoma/patologia , Adenoma/epidemiologiaRESUMO
OBJECTIVE: Acromegaly is a disorder associated with excessive levels of growth hormone (GH) and insulin-like growth factor-1 (IGF-1). In general, GH/IGF-1 excess leads to morphologic craniofacial and acral changes as well as cardiometabolic complications, but the phenotypic changes and clinical presentation of acromegaly differ across species. Here, we review the pathophysiology, clinical presentation and management of acromegaly in humans and cats, and we provide a systematic comparison between this disease across these different species. DESIGN: A comprehensive literature review of pathophysiology, clinical features, diagnosis and management of acromegaly in humans and in cats was performed. RESULTS: Acromegaly is associated with prominent craniofacial changes in both species: frontal bossing, enlarged nose, ears and lips, and protuberant cheekbones are typically encountered in humans, whereas increased width of the head and skull enlargement are commonly found in cats. Malocclusion, prognathism, dental diastema and upper airway obstruction by soft tissue enlargement are reported in both species, as well as continuous growth and widening of extremities resulting in osteoarticular compromise. Increase of articular joint cartilage thickness, vertebral fractures and spine malalignment is more evident in humans, while arthropathy and spondylosis deformans may also occur in cats. Generalized organomegaly is equally observed in both species. Other similarities between humans and cats with acromegaly include heart failure, ventricular hypertrophy, diabetes mellitus, and an overall increased cardiometabolic risk. In GH-secreting pituitary tumours, local compressive effects and behavioral changes are mostly observed in humans, but also present in cats. Cutis verticis gyrata and skin tags are exclusively found in humans, while palmigrade/plantigrade stance may occur in some acromegalic cats. Serum IGF-1 is used for acromegaly diagnosis in both species, but an oral glucose tolerance test with GH measurement is only useful in humans, as glucose load does not inhibit GH secretion in cats. Imaging studies are regularly performed in both species after biochemical diagnosis of acromegaly. Hypophysectomy is the first line treatment for humans and cats, although not always available in veterinary medicine. CONCLUSION: Acromegaly in humans and cats has substantial similarities, as a result of common pathophysiological mechanisms, however species-specific features may be found.
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Acromegalia , Acromegalia/fisiopatologia , Acromegalia/terapia , Gatos , Humanos , Animais , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/análise , Doenças do Gato/fisiopatologiaRESUMO
PURPOSE: The separation between the inside and outside through the skin was fundamental for the evolution of prevertebrates, which grow through extrapituitary circuits, to vertebrates, which grow through the somatotrophic axis, namely pituitary growth hormone (GH). and circulating IGF1.Individuals with untreated isolated growth hormone (GH) deficiency (IGHD) due to a mutation in the GH-releasing hormone receptor (GHRH) gene, residing in Itabaianinha, Brazil, are vulnerable to skin cancer and have reduced sweating. However other aspects of their skin physiology are still unknown. Our objectives were to evaluate the number of skin cancers, skin aging, and functional aspects of the skin in this IGHD cohort. METHODS: Twenty-six IGHD individuals and 26 controls matched by age, sex, ethnicity, and occupation were submitted to a biochemical, dermatological and a functional skin assessment by the Multi Probe Adapter Cutometer® MPA 580. RESULTS: There was no difference in the number of skin cancers and in the degrees of photodamage between the groups. The melanin content in the forearm was similar between the groups but was lower in the buttocks (p = 0.005), as well as skin resistance (p < 0.0001) and elasticity (p = 0.003), lower in the IGHD. There was no difference in hydration and sebum content between the two groups. CONCLUSION: IGHD is apparently associated with a neutral profile in terms of skin cancer and photodamage, with similar melanin on the forearm and lower buttocks, lower skin resistance and elasticity, with hydration and sebum similar to controls.
Assuntos
Hormônio do Crescimento Humano , Pele , Humanos , Masculino , Feminino , Adulto , Pele/metabolismo , Hormônio do Crescimento Humano/deficiência , Pessoa de Meia-Idade , Neoplasias Cutâneas , Envelhecimento da Pele/fisiologia , Adulto Jovem , Fenômenos Fisiológicos da Pele , Nanismo Hipofisário/epidemiologia , AdolescenteRESUMO
Pancreatic GHRHomas (pGHRHomas) with acromegaly have unique conditions, harboring the existence of multiple endocrine neoplasia type 1 (MEN 1). Moreover, pituitary lesions are affected by both protracted ectopic GHRH and loss of menin function. Of significance is the clarification of clinicopathological aspects of pGHRHomas in patients with or without MEN 1. From 1977-2016, thirty-six patients with pGHRHomas were reported. Twenty-two out of 36 patients (61%) had pGHRHomas with MEN 1 and 14 patients did not. The former had a tendency of male predominance, benign tumor behavior and fewer metastasis rather than the latter. The latter is a single pGHRHoma accompanied by pituitary enlargement with somatotroph hyperplasia (hyperplasia) caused by protracted ectopic GHRH. Nine patients with MEN 1 underwent transsphenoidal surgery (TSS). The hyperplasia associated with various pituitary adenomas (PAs) including three GH-related adenomas was observed in seven subjects (32%). In these patients, the resection of their pGHRHomas was feasible. Furthermore, all patients with acromegaly due to pGHRHomas without MEN 1 had non-TSS, whereas approximately 70% of those with MEN 1 had unnecessary TSS. The association with hyperplasia and various PAs suggested that formation of the three GH-related adenomas may be induced by the foundations of MEN 1 gene mutations. J. Med. Invest. 71 : 1-8, February, 2024.