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1.
Heliyon ; 10(12): e33060, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38994081

RESUMEN

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.

2.
Int J Biol Macromol ; 274(Pt 2): 133182, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38885857

RESUMEN

Glycoside hydrolase family 5 (GH5) encompasses enzymes with several different activities, including endo-1,4-ß-mannosidases. These enzymes are involved in mannan degradation, and have a number of biotechnological applications, such as mannooligosaccharide prebiotics production, stain removal and dyes decolorization, to name a few. Despite the importance of GH5 enzymes, only a few members of subfamily 7 were structurally characterized. In the present work, biochemical and structural characterization of Bacillus licheniformis GH5 mannanase, BlMan5_7 were performed and the enzyme cleavage pattern was analyzed, showing that BlMan5_7 requires at least 5 occupied subsites to perform efficient hydrolysis. Additionally, crystallographic structure at 1.3 Å resolution was determined and mannoheptaose (M7) was docked into the active site to investigate the interactions between substrate and enzyme through molecular dynamic (MD) simulations, revealing the existence of a - 4 subsite, which might explain the generation of mannotetraose (M4) as an enzyme product. Biotechnological application of the enzyme in stain removal was investigated, demonstrating that BlMan5_7 addition to washing solution greatly improves mannan-based stain elimination.


Asunto(s)
Bacillus licheniformis , Dominio Catalítico , Mutagénesis Sitio-Dirigida , Bacillus licheniformis/enzimología , Bacillus licheniformis/genética , Cristalografía por Rayos X , Simulación de Dinámica Molecular , Manosidasas/química , Manosidasas/genética , Manosidasas/metabolismo , Especificidad por Sustrato , Hidrólisis , Tetrosas/química , Tetrosas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Conformación Proteica , Mananos/química , Mananos/metabolismo , beta-Manosidasa/química , beta-Manosidasa/genética , beta-Manosidasa/metabolismo , Modelos Moleculares , Simulación del Acoplamiento Molecular , Oligosacáridos
3.
Int J Biol Macromol ; 269(Pt 1): 132036, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38697429

RESUMEN

Alpha-glucosidase inhibitors play an important role in Diabetes Mellitus (DM) treatment since they prevent postprandial hyperglycemia. The Glycoside Hydrolase family 13 (GH13) is the major family of enzymes acting on substrates containing α-glucoside linkages, such as maltose and amylose/amylopectin chains in starch. Previously, our group identified glycoconjugate 1H-1,2,3-triazoles (GCTs) inhibiting two GH13 α-glycosidases: yeast maltase (MAL12) and porcine pancreatic amylase (PPA). Here, we combined kinetic studies and computational methods on nine GCTs to characterize their inhibitory mechanism. They all behaved as reversible inhibitors, and kinetic models encompassed noncompetitive and various mechanisms of mixed-type inhibition for both enzymes. Most potent inhibitors displayed Ki values of 30 µM for MAL12 (GPESB16) and 37 µM for PPA (GPESB15). Molecular dynamics and docking simulations indicated that on MAL12, GPESB15 and GPESB16 bind in a cavity adjacent to the active site, while on the PPA, GPESB15 was predicted to bind at the entrance of the catalytic site. Notably, despite its putative location within the active site, the binding of GPESB15 does not obstruct the substrate's access to the cleavage site. Our study contributes to paving the way for developing novel therapeutic strategies for managing DM-2 through GH13 α-glycosidases inhibition.


Asunto(s)
Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Cinética , Ligandos , Porcinos , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/química , Animales , Dominio Catalítico , alfa-Glucosidasas/metabolismo , alfa-Glucosidasas/química , Glicósido Hidrolasas/química , Glicósido Hidrolasas/metabolismo , Glicósido Hidrolasas/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Triazoles/química , Triazoles/farmacología , Modelos Moleculares
4.
World J Microbiol Biotechnol ; 40(7): 201, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38736020

RESUMEN

Cariogenic biofilms have a matrix rich in exopolysaccharides (EPS), mutans and dextrans, that contribute to caries development. Although several physical and chemical treatments can be employed to remove oral biofilms, those are only partly efficient and use of biofilm-degrading enzymes represents an exciting opportunity to improve the performance of oral hygiene products. In the present study, a member of a glycosyl hydrolase family 66 from Flavobacterium johnsoniae (FjGH66) was heterologously expressed and biochemically characterized. The recombinant FjGH66 showed a hydrolytic activity against an early EPS-containing S. mutans biofilm, and, when associated with a α-(1,3)-glucosyl hydrolase (mutanase) from GH87 family, displayed outstanding performance, removing more than 80% of the plate-adhered biofilm. The mixture containing FjGH66 and Prevotella melaninogenica GH87 α-1,3-mutanase was added to a commercial mouthwash liquid to synergistically remove the biofilm. Dental floss and polyethylene disks coated with biofilm-degrading enzymes also degraded plate-adhered biofilm with a high efficiency. The results presented in this study might be valuable for future development of novel oral hygiene products.


Asunto(s)
Biopelículas , Dextranasa , Flavobacterium , Glicósido Hidrolasas , Streptococcus mutans , Biopelículas/crecimiento & desarrollo , Dextranasa/metabolismo , Dextranasa/genética , Flavobacterium/enzimología , Flavobacterium/genética , Streptococcus mutans/enzimología , Streptococcus mutans/genética , Glicósido Hidrolasas/metabolismo , Glicósido Hidrolasas/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Hidrólisis , Biotecnología/métodos
5.
Endocrine ; 84(3): 1116-1124, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703329

RESUMEN

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.


Asunto(s)
Hormona de Crecimiento Humana , Piel , Humanos , Masculino , Femenino , Adulto , Piel/metabolismo , Hormona de Crecimiento Humana/deficiencia , Persona de Mediana Edad , Neoplasias Cutáneas , Envejecimiento de la Piel/fisiología , Adulto Joven , Fenómenos Fisiológicos de la Piel , Enanismo Hipofisario/epidemiología , Adolescente
6.
Endocrinology ; 165(7)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38728240

RESUMEN

GH acts in numerous organs expressing the GH receptor (GHR), including the brain. However, the mechanisms behind the brain's permeability to GH and how this hormone accesses different brain regions remain unclear. It is well-known that an acute GH administration induces phosphorylation of the signal transducer and activator of transcription 5 (pSTAT5) in the mouse brain. Thus, the pattern of pSTAT5 immunoreactive cells was analyzed at different time points after IP or intracerebroventricular GH injections. After a systemic GH injection, the first cells expressing pSTAT5 were those near circumventricular organs, such as arcuate nucleus neurons adjacent to the median eminence. Both systemic and central GH injections induced a medial-to-lateral pattern of pSTAT5 immunoreactivity over time because GH-responsive cells were initially observed in periventricular areas and were progressively detected in lateral brain structures. Very few choroid plexus cells exhibited GH-induced pSTAT5. Additionally, Ghr mRNA was poorly expressed in the mouse choroid plexus. In contrast, some tanycytes lining the floor of the third ventricle expressed Ghr mRNA and exhibited GH-induced pSTAT5. The transport of radiolabeled GH into the hypothalamus did not differ between wild-type and dwarf Ghr knockout mice, indicating that GH transport into the mouse brain is GHR independent. Also, single-photon emission computed tomography confirmed that radiolabeled GH rapidly reaches the ventral part of the tuberal hypothalamus. In conclusion, our study provides novel and valuable information about the pattern and mechanisms behind GH transport into the mouse brain.


Asunto(s)
Encéfalo , Hormona del Crecimiento , Receptores de Somatotropina , Factor de Transcripción STAT5 , Animales , Factor de Transcripción STAT5/metabolismo , Factor de Transcripción STAT5/genética , Encéfalo/metabolismo , Hormona del Crecimiento/metabolismo , Ratones , Receptores de Somatotropina/metabolismo , Receptores de Somatotropina/genética , Masculino , Ratones Noqueados , Ratones Endogámicos C57BL , Fosforilación , Plexo Coroideo/metabolismo , Hipotálamo/metabolismo , Inyecciones Intraventriculares
7.
Carbohydr Polym ; 337: 122141, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38710568

RESUMEN

Production of value-added compounds and sustainable materials from agro-industrial residues is essential for better waste management and building of circular economy. This includes valorization of hemicellulosic fraction of plant biomass, the second most abundant biopolymer from plant cell walls, aiming to produce prebiotic oligosaccharides, widely explored in food and feed industries. In this work, we conducted biochemical and biophysical characterization of a prokaryotic two-domain R. champanellensis xylanase from glycoside hydrolase (GH) family 30 (RcXyn30A), and evaluated its applicability for XOS production from glucuronoxylan in combination with two endo-xylanases from GH10 and GH11 families and a GH11 xylobiohydrolase. RcXyn30A liberates mainly long monoglucuronylated xylooligosaccharides and is inefficient in cleaving unbranched oligosaccharides. Crystallographic structure of RcXyn30A catalytic domain was solved and refined to 1.37 Å resolution. Structural analysis of the catalytic domain releveled that its high affinity for glucuronic acid substituted xylan is due to the coordination of the substrate decoration by several hydrogen bonds and ionic interactions in the subsite -2. Furthermore, the protein has a larger ß5-α5 loop as compared to other GH30 xylanases, which might be crucial for creating an additional aglycone subsite (+3) of the catalytic site. Finally, RcXyn30A activity is synergic to that of GH11 xylobiohydrolase.


Asunto(s)
Endo-1,4-beta Xilanasas , Microbioma Gastrointestinal , Glucuronatos , Oligosacáridos , Xilosidasas , Glucuronatos/metabolismo , Glucuronatos/química , Oligosacáridos/química , Oligosacáridos/metabolismo , Endo-1,4-beta Xilanasas/metabolismo , Endo-1,4-beta Xilanasas/química , Xilosidasas/metabolismo , Xilosidasas/química , Humanos , Cristalografía por Rayos X , Xilanos/química , Xilanos/metabolismo , Dominio Catalítico , Modelos Moleculares , Especificidad por Sustrato
8.
J Endocrinol Invest ; 47(11): 2797-2807, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38627331

RESUMEN

PURPOSE: Individuals with isolated GH deficiency (IGHD) due to a mutation in the GHRH receptor gene have a normal life expectancy and above 50 years of age, similar total cognitive performance, with better attention and executive function than controls. Our objectives were to evaluate their brain morphometry and brain aging using MRI. METHODS: Thirteen IGHD and 14 controls matched by age, sex, and education, were enrolled. Quantitative volumetric data and cortical thickness were obtained by automatic segmentation using Freesurfer software. The volume of each brain region was normalized by the intracranial volume. The difference between the predicted brain age estimated by MRI using a trained neuronal network, and the chronological age, was obtained. p < 0.005 was considered significant and 0.005 < p < 0.05 as a suggestive evidence of difference. RESULTS: In IGHD, most absolute values of cortical thickness and regional brain volumes were similar to controls, but normalized volumes were greater in the white matter in the frontal pole and in the insula bilaterally, and in the gray matter, in the right insula and in left Caudate (p < 0.005 for all comparisons) We also noticed suggestive evidence of a larger volume in IGHD in left thalamus (p = 0.006), right thalamus (p = 0.025), right caudate (p = 0.046) and right putamen (p = 0.013). Predicted brain ages were similar between groups. CONCLUSION: IGHD is primarily associated with similar absolute brain measurements, and a set of larger normalized volumes, and does not appear to alter the process of brain aging.


Asunto(s)
Envejecimiento , Encéfalo , Hormona de Crecimiento Humana , Imagen por Resonancia Magnética , Humanos , Femenino , Masculino , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Envejecimiento/patología , Envejecimiento/fisiología , Hormona de Crecimiento Humana/deficiencia , Adulto , Enanismo Hipofisario/patología , Estudios de Casos y Controles , Anciano , Tamaño de los Órganos
9.
J Integr Neurosci ; 23(2): 32, 2024 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-38419439

RESUMEN

The role of growth hormone (GH) in the central nervous system (CNS) involves neuroprotection, neuroregeneration, formation of axonal projections, control of cognition, and regulation of metabolism. As GH induces insulin-like growth factor-1 (IGF-1) expression in many tissues, differentiating the specific functions of GH and IGF-1 in the organism is a significant challenge. The actions of GH and IGF-1 in neurons have been more extensively studied than their functions in nonneuronal cells (e.g., microglial cells). Glial cells are fundamentally important to CNS function. Microglia, astrocytes, oligodendrocytes, and tanycytes are essential to the survival, differentiation, and proliferation of neurons. As the interaction of the GH/IGF-1 axis with glial cells merits further exploration, our objective for this review was to summarize and discuss the available literature regarding the genuine effects of GH on glial cells, seeking to differentiate them from the role played by IGF-1 action whenever possible.


Asunto(s)
Hormona del Crecimiento , Factor I del Crecimiento Similar a la Insulina , Hormona del Crecimiento/farmacología , Hormona del Crecimiento/fisiología , Microglía/metabolismo , Astrocitos/metabolismo , Sistema Nervioso Central/metabolismo
10.
Carbohydr Polym ; 329: 121739, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38286536

RESUMEN

Carbohydrate-active enzymes from the glycoside hydrolase family 9 (GH9) play a key role in processing lignocellulosic biomass. Although the structural features of some GH9 enzymes are known, the molecular mechanisms that drive their interactions with cellulosic substrates remain unclear. To investigate the molecular mechanisms that the two-domain Bacillus licheniformis BlCel9A enzyme utilizes to depolymerize cellulosic substrates, we used a combination of biochemical assays, X-ray crystallography, small-angle X-ray scattering, and molecular dynamics simulations. The results reveal that BlCel9A breaks down cellulosic substrates, releasing cellobiose and glucose as the major products, but is highly inefficient in cleaving oligosaccharides shorter than cellotetraose. In addition, fungal lytic polysaccharide oxygenase (LPMO) TtLPMO9H enhances depolymerization of crystalline cellulose by BlCel9A, while exhibiting minimal impact on amorphous cellulose. The crystal structures of BlCel9A in both apo form and bound to cellotriose and cellohexaose were elucidated, unveiling the interactions of BlCel9A with the ligands and their contribution to substrate binding and products release. MD simulation analysis reveals that BlCel9A exhibits higher interdomain flexibility under acidic conditions, and SAXS experiments indicate that the enzyme flexibility is induced by pH and/or temperature. Our findings provide new insights into BlCel9A substrate specificity and binding, and synergy with the LPMOs.


Asunto(s)
Celulosa , Glicósido Hidrolasas , Glicósido Hidrolasas/metabolismo , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Celulosa/química , Carbohidratos , Especificidad por Sustrato
11.
Rev Endocr Metab Disord ; 25(3): 489-504, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38270844

RESUMEN

Pituitary hormone deficiency, hypopituitarism, is a dysfunction resulting from numerous etiologies, which can be complete or partial, and is therefore heterogeneous. This heterogeneity makes it difficult to interpret the results of scientific studies with these patients.Adequate treatment of etiologies and up-to-date hormone replacement have improved morbidity and mortality rates in patients with hypopituitarism. As GH replacement is not performed in a reasonable proportion of patients, especially in some countries, it is essential to understand the known consequences of GH replacement in each subgroup of patients with this heterogeneous dysfunction.In this review on hypopituitarism, we will address some particularities regarding insulin resistance, which is no longer common in these patients with hormone replacement therapy based on current guidelines, metabolic syndrome and its relationship with changes in BMI and body composition, and to vascular complications that need to be prevented taking into account the individual characteristics of each case to reduce mortality rates in these patients.


Asunto(s)
Hipopituitarismo , Resistencia a la Insulina , Síndrome Metabólico , Humanos , Hipopituitarismo/etiología , Hipopituitarismo/metabolismo , Resistencia a la Insulina/fisiología , Síndrome Metabólico/metabolismo , Síndrome Metabólico/complicaciones , Terapia de Reemplazo de Hormonas , Enfermedades Vasculares/etiología , Enfermedades Vasculares/metabolismo , Hormona de Crecimiento Humana/deficiencia , Hormona de Crecimiento Humana/metabolismo
12.
J Clin Endocrinol Metab ; 109(4): e1323-e1327, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-37757837

RESUMEN

Acromegaly treatment has greatly evolved in recent decades, but there are still patients whose acromegaly is not controlled with currently available treatments, and there is a need to improve the treatment burden. Fortunately, there are new treatments under development that may increase treatment efficacy and convenience.


Asunto(s)
Acromegalia , Humanos , Acromegalia/etiología , Acromegalia/terapia , Octreótido , Somatostatina/uso terapéutico , Péptidos Cíclicos , Factor I del Crecimiento Similar a la Insulina
13.
Endocr Connect ; 13(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38019109

RESUMEN

Individuals with untreated isolated GH deficiency (IGHD) due to a mutation in the GHRH receptor gene from Itabaianinha Brazil have increased insulin sensitivity, normal life expectancy, and an extended health span, i.e. the period of life free from disabilities. We hypothesize that their prolonged health span is accompanied by a delayed cognitive decline in senescence. To test this hypothesis, we have administered the Literacy-Independent Cognitive Assessment (LICA) to 15 IGHD individuals aged over 50 years and 15 controls matched by age, sex, years of education, and percentage of illiteracy. All individuals were negative for HIV and syphilis serology, and there were no differences in serum levels of folate, vitamin B12 and TSH between the two groups, while free T4 was higher in the IGHD group. IGHD subjects had a higher total LICA score than controls, 215 (22.7) vs 204.2 (18.1), without reaching statistical significance. Scores of memory, visuoconstruction, language and calculation were similar between the two groups, with better attention (9.5 (1.4) vs 8.3 (1.1), P = 0.01) and executive function (38.3 (4.8) vs 35.1 (2.5), P = 0.03) scores in IGHD. MANCOVA revealed that group (but no age) had a significant effect on the LICA variables (partial eta squared of 0.455, power of 0.812, P = 0.02). This effect is verified on attention (partial eta squared 0.216, power of 0.749, P = 0.01) and executive function (partial eta squared 0.154, power of 0.570, P = 0.03. In conclusion, IGHD in senescence is associated with similar total cognitive performance but better attention and executive function than controls.

14.
JCEM Case Rep ; 1(2): luad034, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37908467

RESUMEN

Acromegaly/giantism results from the chronic excess of growth hormone (GH) and insulin-like growth factor-1 (IGF-1), in more than 96% of cases, due to a GH-secreting pituitary adenoma. Primary treatment of choice is transsphenoidal resection of the adenoma. More than 30% to 40% of operated cases require adjunctive forms of treatment, be it pharmacological or radiotherapeutical. The multimodal treatment of acromegaly has resulted in substantial improvements in the quality of life and life expectancy of these patients. We herein present the complex case of a patient with acromegaly due to a mammosomatotrope adenoma, with a germ-line AIP (aryl hydrocarbon receptor-interacting protein) mutation, who had a chronic and protracted course of more than 15 years during which he was treated with surgery, somatostatin receptor ligands, dopamine agonist, and the GH receptor antagonist pegvisomant. At one point, he was able to come off medications and was even found to be transiently GH-deficient, only to develop acromegaly again after a couple of years.

15.
Int J Mol Sci ; 24(19)2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37833959

RESUMEN

Due to their ability to produce isomaltulose, sucrose isomerases are enzymes that have caught the attention of researchers and entrepreneurs since the 1950s. However, their low activity and stability at temperatures above 40 °C have been a bottleneck for their industrial application. Specifically, the instability of these enzymes has been a challenge when it comes to their use for the synthesis and manufacturing of chemicals on a practical scale. This is because industrial processes often require biocatalysts that can withstand harsh reaction conditions, like high temperatures. Since the 1980s, there have been significant advancements in the thermal stabilization engineering of enzymes. Based on the literature from the past few decades and the latest achievements in protein engineering, this article systematically describes the strategies used to enhance the thermal stability of sucrose isomerases. Additionally, from a theoretical perspective, we discuss other potential mechanisms that could be used for this purpose.


Asunto(s)
Isomerasas , Ingeniería de Proteínas , Temperatura , Sacarosa , Estabilidad de Enzimas
16.
Plant Sci ; 336: 111866, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37714383

RESUMEN

Protein post-translational modification (PTM) is a ubiquitous process that occurs in most proteins. Lysine residues containing an ε-amino group are recognized as hotspots for the addition of different chemical groups. Lysine acetylation, extensively studied in histones, serves as an epigenetic hallmark capable of promoting changes in chromatin structure and availability. Acyl groups derived from molecules involved in carbohydrate and lipid metabolisms, such as lactate, succinate and hydroxybutyrate, were identified as lysine modifications of histones and other proteins. Lysine-acyltransferases do not exhibit significant substrate specificity concerning acyl donors. Furthermore, plant hormones harboring acyl groups often form conjugates with free amino acids to regulate their activity and function during plant physiological processes and responses, a process mediated by GH3 enzymes. Besides forming low-molecular weight conjugates, auxins have been shown to covalently modify proteins in bean seeds. Aside from auxins, other phytohormones with acyl groups are unexplored potential substrates for post-translational acylation of proteins. Using MS data searches, we revealed various proteins with lysine residues linked to auxin, abscisic acid, gibberellic acid, jasmonic acid, and salicylic acid. These findings raise compelling questions about the ability of plant hormones harboring carboxyl groups to serve as new candidates for protein acylation and acting in protein PTM and modulation.

17.
J Neurosci ; 43(40): 6816-6829, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37625855

RESUMEN

Dysfunctions in growth hormone (GH) secretion increase the prevalence of anxiety and other neuropsychiatric diseases. GH receptor (GHR) signaling in the amygdala has been associated with fear memory, a key feature of posttraumatic stress disorder. However, it is currently unknown which neuronal population is targeted by GH action to influence the development of neuropsychiatric diseases. Here, we showed that approximately 60% of somatostatin (SST)-expressing neurons in the extended amygdala are directly responsive to GH. GHR ablation in SST-expressing cells (SSTΔGHR mice) caused no alterations in energy or glucose metabolism. Notably, SSTΔGHR male mice exhibited increased anxiety-like behavior in the light-dark box and elevated plus maze tests, whereas SSTΔGHR females showed no changes in anxiety. Using auditory Pavlovian fear conditioning, both male and female SSTΔGHR mice exhibited a significant reduction in fear memory. Conversely, GHR ablation in SST neurons did not affect memory in the novel object recognition test. Gene expression was analyzed in a micro punch comprising the central nucleus of the amygdala (CEA) and basolateral (BLA) complex. GHR ablation in SST neurons caused sex-dependent changes in the expression of factors involved in synaptic plasticity and function. In conclusion, GHR expression in SST neurons is necessary to regulate anxiety in males, but not female mice. GHR ablation in SST neurons also decreases fear memory and affects gene expression in the amygdala, although marked sex differences were observed. Our findings identified for the first time a neurochemically-defined neuronal population responsible for mediating the effects of GH on behavioral aspects associated with neuropsychiatric diseases.SIGNIFICANCE STATEMENT Hormone action in the brain regulates different neurological aspects, affecting the predisposition to neuropsychiatric disorders, like depression, anxiety, and posttraumatic stress disorder. Growth hormone (GH) receptor is widely expressed in the brain, but the exact function of neuronal GH action is not fully understood. Here, we showed that mice lacking the GH receptor in a group of neurons that express the neuropeptide somatostatin exhibit increased anxiety. However, this effect is only observed in male mice. In contrast, the absence of the GH receptor in somatostatin-expressing neurons decreases fear memory, a key feature of posttraumatic stress disorder, in males and females. Thus, our study identified a specific group of neurons in which GH acts to affect the predisposition to neuropsychiatric diseases.


Asunto(s)
Hormona del Crecimiento , Somatostatina , Femenino , Masculino , Ratones , Animales , Somatostatina/metabolismo , Hormona del Crecimiento/metabolismo , Ansiedad , Miedo , Receptores de Somatotropina/genética , Receptores de Somatotropina/metabolismo , Neuronas/metabolismo
18.
Arch Med Res ; 54(6): 102856, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37481822

RESUMEN

INTRODUCTION: Despite the inherent heterogeneity of the information derived from national registries, they are a useful tool to investigate the epidemiological, clinical, biochemical and treatment outcome characteristics of low prevalence conditions such as acromegaly. Although the information provided by single-center experiences is more homogeneous, these studies usually comprise a limited number of patients and thus, frequently lack statistical power. AREAS COVERED: Registry-based Information regarding the epidemiology, clinical presentation, biochemical and imaging diagnosis, as well as therapeutic outcome and mortality in acromegaly is critically analyzed. EXPERT OPINION: By gathering data from multiple centers in a specific Country, these registries generate important insights into the real-life behavior of this condition, that should be considered, both, in international consensus meetings and in the design of local, Country-specific diagnostic and therapeutic strategies.


Asunto(s)
Acromegalia , Adenoma , Hormona de Crecimiento Humana , Neoplasias Hipofisarias , Humanos , Acromegalia/diagnóstico , Acromegalia/epidemiología , Acromegalia/terapia , Hormona de Crecimiento Humana/uso terapéutico , Adenoma/diagnóstico , Adenoma/tratamiento farmacológico , Somatostatina/uso terapéutico , Resultado del Tratamiento , Sistema de Registros , Factor I del Crecimiento Similar a la Insulina , Neoplasias Hipofisarias/tratamiento farmacológico
19.
J Endocrinol Invest ; 46(12): 2601-2607, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37355525

RESUMEN

PURPOSE: This study aimed to analyze the expression of the IGF type-1 receptor gene (IGF-1r) and IGF-I, GH, testosterone, and IGFBP-3 concentrations in young people subjected to 10 weeks of muscle hypertrophy training. METHODS: IGF-1r expression, serum concentrations of IGF-I, IGFBP-3, GH, and total testosterone, as well as body composition, fat percentage, and body mass index, were determined for 22 healthy young males at three moments of resistance training (first, fifth, and tenth week of training). RESULTS: Throughout the 10 weeks of training, a reduction was observed in the relative expression of the IGF-1r gene (2-ΔΔCT) and an increase in IGF-I and GH concentrations. A reduction in total testosterone concentrations was detected during the recovery period in the fifth week. The IGFBP-3 concentrations did not change throughout the training. CONCLUSIONS: The resistance training protocol prescribed for muscle hypertrophy did not suppress the GH-IGF-I axis, but it did cause alterations in IGF-1r gene expression and in IGF-I kinetics compatible with increased IGF bioactivity.


Asunto(s)
Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Factor I del Crecimiento Similar a la Insulina , Masculino , Humanos , Adulto Joven , Adolescente , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Testosterona , Hipertrofia , Músculos/metabolismo
20.
Endocrine ; 81(3): 547-554, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37198380

RESUMEN

OBJECTIVES: The shoulder is the most mobile joint in the entire human body. During arm elevation, it requires the integrity of a set of muscles, bones, and tendons. Individuals with short stature often need to raise their arms above the shoulder girdle and may have functional restriction or shoulder injuries. The impact of isolated GH deficiency (IGHD) on joints remains not well defined. The purpose of this work is to evaluate the function and structure of the shoulder in short-statured adult individuals with untreated IGHD due to the same homozygous mutation in the GHRH receptor gene. METHODS: A cross-sectional study (evidence 3) was carried out in 20 GH-naive IGHD subjects and 20 age-matched controls. They completed the disabilities of the arm, shoulder, and hand (DASH) questionnaire and shoulder ultrasound (US). Thickness of the anterior, medial, and posterior portions of the supraspinatus tendon and of subacromial space was measured, and the number of individuals with tendinosis or tearing of the supraspinatus tendon was registered. RESULTS: DASH score was similar between IGHD and controls, but IGHD subjects complained less of symptoms (p = 0.002). The number of individual with tears was higher in the controls (p = 0.02). As expected, the absolute US measurements were lower in IGHD, but the magnitude of the reduction was most pronounced in the thickness of the anterior portion of the supraspinatus tendon. CONCLUSION: Adults with lifetime IGHD do not have functional shoulder restrictions, complain less of problems in performing upper extremity activities, and have fewer tendinous injuries than controls.


Asunto(s)
Enanismo Hipofisario , Hipopituitarismo , Adulto , Humanos , Enanismo Hipofisario/genética , Hombro , Estudios Transversales , Hormona del Crecimiento
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