SENP2-mediated SERCA2a deSUMOylation increases calcium overload in cardiomyocytes to aggravate myocardial ischemia/reperfusion injury / 中华医学杂志(英文版)

BACKGROUND@#Sarcoplasmic reticulum calcium ATPase 2a (SERCA2a) is a key protein that maintains myocardial Ca 2+ homeostasis. The present study aimed to investigate the mechanism underlying the SERCA2a-SUMOylation (small ubiquitin-like modifier) process after ischemia/reperfusion injury (I/RI) in vitro and in vivo .@*METHODS@#Calcium transient and systolic/diastolic function of cardiomyocytes isolated from Serca2a knockout (KO) and wild-type mice with I/RI were compared. SUMO-relevant protein expression and localization were detected by quantitative real-time PCR (RT-qPCR), Western blotting, and immunofluorescence in vitro and in vivo . Serca2a-SUMOylation, infarct size, and cardiac function of Senp1 or Senp2 overexpressed/suppressed adenovirus infected cardiomyocytes, were detected by immunoprecipitation, triphenyltetrazolium chloride (TTC)-Evans blue staining, and echocardiography respectively.@*RESULTS@#The results showed that the changes of Fura-2 fluorescence intensity and contraction amplitude of cardiomyocytes decreased in the I/RI groups and were further reduced in the Serca2a KO + I/RI groups. Senp1 and Senp2 messenger ribose nucleic acid (mRNA) and protein expression levels in vivo and in cardiomyocytes were highest at 6 h and declined at 12 h after I/RI. However, the highest levels in HL-1 cells were recorded at 12 h. Senp2 expression increased in the cytoplasm, unlike that of Senp1. Inhibition of Senp2 protein reversed the I/RI-induced Serca2a-SUMOylation decline, reduced the infarction area, and improved cardiac function, while inhibition of Senp1 protein could not restore the above indicators.@*CONCLUSION@#I/RI activated Senp1 and Senp2 protein expression, which promoted Serca2a-deSUMOylation, while inhibition of Senp2 expression reversed Serca2a-SUMOylation and improved cardiac function.

Advances in the preclinical and clinical research of proteolysis targeting chimera / 生物工程学报

Proteolysis targeting chimera (PROTAC) refers to heterobifunctional small molecules that can simultaneously bind an E3 ubiquitin ligase and a target protein, enabling specific degradation of the target protein with the aid of the ubiquitin proteasome system. At present, most PROTAC drugs are in the clinical trial stage, and the ligands are mainly non-covalent compounds. PROTAC drugs have the advantage of overcoming drug resistance and degrading "undruggable" target proteins, but non-covalent ligands could lead to the hook effect that undermines drug efficacy. With its own advantages, covalent ligands can avoid the occurrence of this phenomenon, which is of great help to the development of PROTAC. This review summarizes the progress in preclinical and clinical research and application of PROTAC molecules targeting three different classes of protein targets, including intranuclear, transmembrane, and cytosolic proteins. We also offer perspective discussions to provide research ideas and references for the future development of PROTAC.

Expression of BmSPI38 tandem multimers in Escherichia coli and its antifungal activity / 生物工程学报

The aim of this study was to prepare tandem multimeric proteins of BmSPI38, a silkworm protease inhibitor, with better structural homogeneity, higher activity and stronger antifungal ability by protein engineering. The tandem multimeric proteins of BmSPI38 were prepared by prokaryotic expression technology. The effects of tandem multimerization on the structural homogeneity, inhibitory activity and antifungal ability of BmSPI38 were explored by in-gel activity staining of protease inhibitor, protease inhibition assays and fungal growth inhibition experiments. Activity staining showed that the tandem expression based on the peptide flexible linker greatly improved the structural homogeneity of BmSPI38 protein. Protease inhibition experiments showed that the tandem trimerization and tetramerization based on the linker improved the inhibitory ability of BmSPI38 to microbial proteases. Conidial germination assays showed that His6-SPI38L-tetramer had stronger inhibition on conidial germination of Beauveria bassiana than that of His6-SPI38-monomer. Fungal growth inhibition assay showed that the inhibitory ability of BmSPI38 against Saccharomyces cerevisiae and Candida albicans could be enhanced by tandem multimerization. The present study successfully achieved the heterologous active expression of the silkworm protease inhibitor BmSPI38 in Escherichia coli, and confirmed that the structural homogeneity and antifungal ability of BmSPI38 could be enhanced by tandem multimerization. This study provides important theoretical basis and new strategies for cultivating antifungal transgenic silkworm. Moreover, it may promote the exogenous production of BmSPI38 and its application in the medical field.

Risk factors analysis of protein energy wasting in children with chronic kidney disease / 中华儿科杂志

Objective: To analyze the clinical characteristics and risk factors of protein energy wasting (PEW) in children with chronic kidney disease (CKD). Methods: Clinical data of 231 children with chronic kidney disease hospitalized in Beijing Children's Hospital affiliated to Capital Medical University from January 2018 to January 2023 were retrospectively analyzed to explore the incidence of PEW. According to the diagnostic criteria of CKDPEW, they were divided into a CKDPEW group and a non PEW group. The comparison between the groups was performed by independent-sample t test and Chi-squared test, and the risk factors were analyzed by multivariate Logistic regression. Results: Among the 231 children, there were 138 males and 93 females, with a visiting age of 9.9 (7.9, 16.0) years; 6 cases were in stage 1, 14 cases in stage 2, 51 cases in stage 3, 36 cases in stage 4, and 124 cases in stage 5. A total of 30 children (13.0%) with CKD PEW were diagnosed at the age of 7. 1 (3.8, 13.2) years, including 1 case in stage 1, 1 case in stage 2, 5 cases in stage 3, 5 cases in stage 4, and 18 cases in stage 5. There were a total of 201 cases (87.0%) in the non PEW group, diagnosed at the age of 11.8 (8.5, 12.2) years, including 5 cases in stage 1, 13 cases in stage 2, 46 cases in stage 3, 31 cases in stage 4, and 106 cases in stage 5. The Chi-squared test and t test showed that the systolic blood pressure, diastolic blood pressure, birth weight and carbon dioxide binding capacity of the CKD PEW group were lower than those of the non PEW group ((109±22) vs. (120±20) mmHg (1 mmHg=0.133 kPa), (72±19) vs. (79±16) mmHg, (2.9±0.5) vs. (3.2±0.6) kg, (17±4) vs. (19±4) mmol/L,t=2.85, 2.14, 0.67, 2.63, all P<0.05). Multivariate logistic regression analysis showed that carbon dioxide binding capacity and birth weight were independent protective factors of CKDPEW in children (OR=0.81 and 0.36, 95%CI=0.73-0.90 and 0.17-0.77, respectively; both P<0.01); the risk of PEW in CKD children decreased by 0.187 times for every 1 mmol/L increment in carbon dioxide binding capacity, and 0.638 times for every 1 kg increment in birth weight. Conclusions: The incidence of protein energy expenditure in children with chronic kidney disease is lower than that in the previous researches. PEW can appear in CKD 1-2 stage, and attention should be paid to it in the early stage of CKD in clinical practice. Low birth weight CKD children are susceptible to PEW, and actively correcting metabolic acidosis can reduce the risk of CKDPEW.

Research progress on plant-derived exosome-like nanoparticles and their applications / 中国中药杂志

Plant-derived exosome-like nanoparticles(PELNs) are a class of membranous vesicles with diameters approximately ranging from 30 to 300 nm, isolated from plant tissues. They contain components such as proteins, lipids, and nucleic acids. PELNs play an important role in the metabolism of plant substances and immune defense, and can also cross-regulate the physiological activities of fungi and animal cells, showing significant potential applications. In recent years, research on PELNs has significantly increased, highlighting three main issues:(1) the mixed sources of plant materials for PELNs;(2) the lack of a unified system for isolating and characterizing PELNs;(3) the urgent need to elucidate the molecular mechanisms underlying the cross-regulation of biological functions by PELNs. This article focused on these concerns. It began by summarizing the biological origin and composition of PELNs, discussing the techniques for isolating and characterizing PELNs, and analyzing their biomedical applications and potential future research directions., aiming to promote the establishment of standardized research protocols for PELNs and provide theoretical references for in-depth exploration of the mechanisms underlying PELNs' cross-regulatory effects.

The extracellular vesicles from gram-positive bacteria: a review / 生物工程学报

Extracellular vesicles (EVs), also known as membrane vesicles, are vesicular bodies secreted by eukaryotic cells and bacteria. EVs can carry proteins, DNA, RNA, and various metabolites for the exchange and transmission of substances between cells. They play contents-dependent physiological functions, such as delivering nutrients, participating in immune response, and treating cancers. Currently, most studies focus on the exploration of vesicles secreted by eukaryotic cells and gram-negative bacteria, while few studies focus on gram-positive bacteria. This review summarized the production, content composition, physiological function, and engineering of EVs secreted by gram-positive bacteria, and prospected future perspectives in this area.

The roles of intraflagellar transport (IFT) protein 25 in mammalian signaling transduction and flagellogenesis / 亚洲男科学杂志(英文版)

Cilium, an organelle with a unique proteome and organization, protruding from the cell surface, generally serves as a force generator and signaling compartment. During ciliogenesis, ciliary proteins are synthesized in cytoplasm and transported into cilia by intraflagellar transport (IFT) particles, where the inner counterparts undergo reverse trafficking. The homeostasis of IFT plays a key role in cilial structure assembly and signaling transduction. Much progress has been made on the mechanisms and functions of IFT; however, recent studies have revealed the involvement of IFT particle subunits in organogenesis and spermatogenesis. In this review, we discuss new concepts concerning the molecular functions of IFT protein IFT25 and how its interactions with other IFT particle subunits are involved in mammalian development and fertility.

The adhesion mechanism of barnacle and its cement proteins: a review / 生物工程学报

The adhesive protein secreted by marine sessile animals can resist the resistance of water and exert stickiness under the humid environment. It has become a candidate for the development of high-performance materials in the field of biomedicine and bionics. Barnacles are as one of the marine macrofoulers that can be firmly attached to the underwater substrate materials with different surface characteristics through its cement proteins. To date, the adhesion process of barnacle has been understood in-depth, but the specific underwater adhesion mechanism has not been elucidated and needs further exploration. This review first presented an overview of barnacle and its adhesion process, followed by summarizing the advances of barnacle adhesive protein, its production methods, and applications. Moreover, challenges and future perspectives were prospected.

Advances of targeted protein degradation technology and its applications in diseases therapy / 生物工程学报

Targeted protein degradation (TPD) technology facilitates specific and efficient degradation of disease-related proteins through hijacking the two major protein degradation systems in mammalian cells: ubiquitin-proteasome system and lysosome pathway. Compared with traditional small molecule-inhibitors, TPD-based drugs exhibit the characteristics of a broader target spectrum. Compared with techniques interfere with protein expression on the gene and mRNA level, TPD-based drugs are target-specific, efficaciously rapid, and not constrained by post-translational modification of proteins. In the past 20 years, various TPD-based technologies have been developed. Most excitingly, two TPD-based therapeutic drugs have been approved by FDA for phase Ⅰ clinical trials in 2019. Despite of the early stage characteristics and various obstructions of the TPD technology, it could serve as a powerful tool for the development of novel drugs. This review summarizes the advances of different degradation systems based on TPD technologies and their applications in disease therapy. Moreover, the advantages and challenges of various technologies were discussed systematically, with the aim to provide theoretical guidance for further application of TPD technologies in scientific research and drug development.

Expression of Autophagy-Associated Protein in Rat Muscle Tissues after Antemortem and Postmortem Injury / 法医学杂志

Objective To study the expression of the three autophagy-associated proteins, BECN1, LC3 and p62, after the injury of the skeletal muscle of rats and to explore its application in differentiation between antemortem and postmortem injury. Methods The 72 healthy Sprague-Dawley rats were randomly divided into the undamaged control group, the antemortem injury group （0.5 h, 1 h, 2 h, 4 h, 8 h, 16 h and 24 h） and postmortem injury group （0.5 h, 1 h, 2 h and 4 h）. A model of the injured right hind limb of rats was constructed. The expressions of the autophagy-associated proteins, BECN1, LC3-2/LC3-1 and p62, in the control group, the antemortem injury group and postmortem injury group were detected by Western blotting method. The data were respectively centralized and standardized and the orthogonal partial least square-discrimination analysis （OPLS-DA） identification model of antemortem and postmortem injury groups was constructed. Results The expression of BECN1, p62 protein and LC3-2/LC3-1 after the injury of the skeletal muscle of the rats showed different degrees of changes, but the differences among the 3 groups had no statistical significance. Antemortem and postmortem injury groups can be distinguished by centralizing and standardizing the expression levels of autophagy protein BECN1 and the ratio of LC3-2/LC3-1. The principal components extracted from OPLS-DA model of antemortem injury and postmortem injury had a relatively good interpretation of the model （Rx2=0.563, Ry2=0.439）, but it were less predictive （Q2=0.366）. Conclusion The expression of BECN1 and the ratio of LC3-2/LC3-1 in injured local tissue of the rat skeletal muscle can be used for the differentiation of antemortem injury group and postmortem injury group.

The insertion of bioactive peptides at the C-terminal end of an 11S globulin changes the structural stability and improves the antihypertensive activity

BACKGROUND: The 11S globulin from amaranth is the most abundant storage protein in mature seeds and is well recognized for its nutritional value. We used this globulin to engineer a new protein by adding a four valinetyrosine antihypertensive peptide at its C-terminal end to improve its functionality. The new protein was named AMR5 and expressed in the Escherichia coli BL21-CodonPlus(DE3)-RIL strain using a custom medium (F8PW) designed for this work. RESULTS: The alternative medium allowed for the production of 652 mg/L expressed protein at the flask level, mostly in an insoluble form, and this protein was subjected to in vitro refolding. The spectrometric analysis suggests that the protein adopts a ß/α structure with a small increment of α-helix conformation relative to the native amaranth 11S globulin. Thermal and urea denaturation experiments determined apparent Tm and C1/2 values of 50.4°C and 3.04 M, respectively, thus indicating that the antihypertensive peptide insertion destabilized the modified protein relative to the native one. AMR5 hydrolyzed by trypsin and chymotrypsin showed 14- and 1.3-fold stronger inhibitory activity against angiotensin I-converting enzyme (IC50 of 0.034 mg/mL) than the unmodified protein and the previously reported amaranth acidic subunit modified with antihypertensive peptides, respectively. CONCLUSION: The inserted peptide decreases the structural stability of amaranth 11S globulin and improves its antihypertensive activity.

Reserva funcional renal: concepto y aplicabilidad potencial en la práctica clínica / Renal functional reserve: concept and potential application in clinical practice

Renal functional reserve (RFR) is the capacity of the kidney to increase its glomerular filtration rate (GFR) in response to physiological or pathological stimuli. The most commonly used stimuli to assess this reserve are an oral load of proteins of animal origin, amino acid infusions, dopamine, glucagon or combinations of them. RFR is calculated as the difference between stimulated and baseline GFR. Vegetarians have lower baseline GFR than the general population and an increased RFR. Subjects with only one kidney and those suffering from chronic nephropathies usually have a reduced or absent RFR despite having normal basal GFR. Quantification of RFR may be useful to detect subclinical renal damage, physiological conditions that reduce baseline GFR, evaluation of potential donors for kidney transplantation, suspected hyperfiltration, detection of renal lability against acute injuries or pregnancy and the evaluation after an acute renal injury when renal function seems to be recovered and residual subclinical damage is suspected.

Resultados de la implementación de un protocolo de soporte nutricional en grandes quemados pediátricos internados en la Unidad de Cuidados Intensivos / Results of the implementation of a nutritional support protocol for major burn pediatric patients hospitalized in the Intensive Care Unit

Introducción: "Gran quemado" es quien sufre lesiones por daño térmico que afectan más del 30% de su superficie corporal (SC). El hipercatabolismo secundario causa pérdida de masa magra y retraso de la cicatrización de heridas. Objetivo: Describir y analizar los resultados de la implementación de un protocolo de soporte nutricional en niños quemados graves internados en una Unidad de Cuidados Intensivos durante las primeras 6 semanas evolutivas. Población y métodos: Diseño analítico, prospectivo, observacional y longitudinal. Se midieron peso, talla, porcentaje de SC quemada, días de internación en la Unidad de Cuidados Intensivos y mortalidad. Se analizaron tasa metabólica basal por calorimetría indirecta y fórmula de Schofield, cobertura de aporte energético y proteico, prealbúmina, proteína C reactiva, vitaminas A, D, E, cobre y zinc semanales. Resultados: Se incluyeron 18 pacientes (media: 3,9 años, 49% de SC quemada). Se alcanzó la media de objetivo energético en la segunda semana y el requerimiento proteico en la semana 6. Doce pacientes requirieron nutrición parenteral complementaria sin complicaciones. Se hallaron parámetros de hipermetabolismo, que se normalizaron a las 4-6 semanas del ingreso, excepto la proteína C reactiva. Las vitaminas A y E y elementos traza (zinc y cobre) estaban descendidos al ingreso con mejoría posterior. La vitamina D persistió en valores bajos. Un paciente falleció. Conclusiones: La implementación del protocolo permitió lograr el aporte de la totalidad del requerimiento energético; la cobertura del requerimiento proteico se postergó hasta la semana 6. Es necesario hacer hincapié en resolver las limitaciones para alcanzar este último.

Introduction. "Major burn" is used to describe a person who suffers thermal damage affecting more than 30% of his/her total body surface area (TBSA). The secondary hypercatabolism causes lean body mass loss and delayed wound healing. Objective. To describe and analyze the results of implementing a nutritional support protocol for pediatric burn patients hospitalized in the intensive care unit in the first 6 weeks. Population an d methods. Analytical, prospective, observational, and longitudinal design. Weight, height, %TBSA, length of stay in the intensive care unit, and mortality were measured. The basal metabolic rate was measured by indirect calorimetry and the Schofield equation, and protein and energy intake, prealbumin, C-reactive protein, vitamins A, D, E, copper, and zinc levels were analyzed every week. Results. Eighteen patients were included (mean: 3.9 years old, 49%TBSA). The mean energy target was achieved by week 2 and protein requirements were met by week 6. Twelve patients required complementary parenteral nutrition and there were no complications. Hypermetabolism parameters were observed, which returned to normal 4-6 weeks after hospitalization, except for C-reactive protein. Vitamins A and E and trace elements (zinc and copper) were reduced at the time of admission and showed a subsequent improvement. Vitamin D remained low. One patient died. Conclusions. Implementing the protocol was useful to cover the total energy requirement; the coverage of protein requirements was delayed until week 6. It is necessary to focus on solving limitations to achieve the latter.

Screening on serum biomarkers in idiopathic pulmonary fibrosis patients by proteomics technology / 中华流行病学杂志

Objective: Applying the proteomics technology to identify proteins differentially in serums of idiopathic pulmonary fibrosis patients and normal population. Methods: The study included serum samples from idiopathic pulmonary fibrosis group and normal controlled group with 30 cases of each, from the Second Hospital of Shandong University, between October 2014 and October 2015. Proteins differentially expressed in serums were quantified by the isobaric tags for relative and absolute quantization coupled with two-dimensional liquid chromatography/tandem mass spectrometry technology. The proteins were analyzed in terms of molecular function, cell location and biological processes for showing the key protein molecules which were related to the development of idiopathic pulmonary fibrosis. Results: A total of 490 kinds of proteins (with confidence coefficient above 95%) were identified by mass spectrometry and 25 kinds of differentially expressed proteins were found. Compared with the control group, we found 4 types of up-regulated proteins and 21 down-regulated ones in the serum of idiopathic pulmonary fibrosis patients. Data from the Gene ontology analysis showed that most differentially expressed proteins were in the extracellular region (92%) while pathway enrichment analysis showed that most proteins were involved in the complement and coagulation cascade pathway. Conclusion: Proteins related to the complement system coagulation cascade pathway, and the proteins function need to be further studied.

Cardiac protein expression patterns are associated with distinct inborn exercise capacity in non-selectively bred rats

In the present study, we successfully demonstrated for the first time the existence of cardiac proteomic differences between non-selectively bred rats with distinct intrinsic exercise capacities. A proteomic approach based on two-dimensional gel electrophoresis coupled to mass spectrometry was used to study the left ventricle (LV) tissue proteome of rats with distinct intrinsic exercise capacity. Low running performance (LRP) and high running performance (HRP) rats were categorized by a treadmill exercise test, according to distance run to exhaustion. The running capacity of HRPs was 3.5-fold greater than LRPs. Protein profiling revealed 29 differences between HRP and LRP rats (15 proteins were identified). We detected alterations in components involved in metabolism, antioxidant and stress response, microfibrillar and cytoskeletal proteins. Contractile proteins were upregulated in the LVs of HRP rats (α-myosin heavy chain-6, myosin light chain-1 and creatine kinase), whereas the LVs of LRP rats exhibited upregulation in proteins associated with stress response (aldehyde dehydrogenase 2, α-crystallin B chain and HSPβ-2). In addition, the cytoskeletal proteins desmin and α-actin were upregulated in LRPs. Taken together, our results suggest that the increased contractile protein levels in HRP rats partly accounted for their improved exercise capacity, and that proteins considered risk factors to the development of cardiovascular disease were expressed in higher amounts in LRP animals.

Evolución de los pacientes graves con ventilación mecánica invasiva según el catabolismo proteico / Evolution of severe patients with invasive mechanical ventilation according to protein catabolism

Introducción: el catabolismo proteico es un indicador de la respuesta metabólica a la agresión. Objetivo: determinar la evolución de los pacientes con ventilación mecánica invasiva y su posible asociación con el catabolismo proteico, por categorías diagnósticas. Método: se realizó un estudio observacional, analítico y prospectivo, conto dos los pacientes sometidos a ventilación mecánica invasiva, ingresados en cuidados intensivos desde el 2001 hasta el 2007 y fueron clasificaron según la categoría diagnóstica (trauma, clínico y quirúrgico). Se midió el peso corporal al ingreso. Se evaluó el catabolismo proteico durante los primeros 3 días del ingreso, con la urea plasmática, la creatininuria y el nitrógeno ureico urinario. Se contrastaron con las variables dependientes: mortalidad, morbilidad y el tiempo de ventilación mecánica. Resultados: se estudiaron 262 pacientes; 88 presentaban trauma, 89 afecciones clínicas y 85 afecciones quirúrgicas. El catabolismo proteico fue alto en el trauma y se asoció a la mortalidad, a la disfunción múltiple de órganos y al tiempo prolongado de ventilación mecánica; en los pacientes quirúrgicos se asoció a la morbilidad. Los valores bajos de creatininuria, evidenciaron asociación con la mayor mortalidad, morbilidad y el tiempo prolongado de ventilación mecánica. Conclusiones: el catabolismo proteico se asoció a la evolución del paciente con ventilación mecánica invasiva, en las categorías trauma y quirúrgicos. No se evidenció asociación en la categoría clínica(AU)

Introduction: Protein catabolism is an indicator of the metabolic response to injury. Objective: To determine the evolution of patients with mechanical invasive ventilation and its possible association with protein catabolism by diagnostic category. Method: An observational, analytical and prospective study was performed with all patients undergoing mechanical invasive ventilation admitted to Intensive Care from 2001 to 2007 and classified according to the diagnostic category (trauma, clinical and surgical). Body weight was measured at admission. Protein catabolism was evaluated during the first 3 days of admission, with plasma urea, creatinine and urinary urea nitrogen. They were contrasted with the dependent variables: mortality, morbidity and time of mechanical ventilation. Results: We studied 262 patients; 88 presented trauma, 89 clinical conditions and 85 surgical conditions. Protein catabolism was high in trauma and associated with mortality, multiple organ dysfunction and prolonged mechanical ventilation; in surgical patients was associated with morbidity. The low values of urine creatinine,were associated with the greater mortality, morbidity and the prolonged time of mechanical ventilation. Conclusions: Protein catabolism was associated with the evolution of the patient with mechanical invasive ventilation, in the trauma and surgical categories. There was no evidence of association in the clinical category(AU)

Mitochondrial proteomic profile of complex IV deficiency fibroblasts: rearrangement of oxidative phosphorylation complex/supercomplex and other metabolic pathways / Perfil proteómico mitocondrial de los fibroblastos con deficiencia del complejo IV: reordenamiento del complejo/supercomplejo de la fosforilación oxidativa y otras vías metabólicas

Abstract: Background: Mitochondriopathies are multisystem diseases affecting the oxidative phosphorylation (OXPHOS) system. Skin fibroblasts are a good model for the study of these diseases. Fibroblasts with a complex IV mitochondriopathy were used to determine the molecular mechanism and the main affected functions in this disease. Methods: Skin fibroblast were grown to assure disease phenotype. Mitochondria were isolated from these cells and their proteome extracted for protein identification. Identified proteins were validated with the MitoMiner database. Results: Disease phenotype was corroborated on skin fibroblasts, which presented a complex IV defect. The mitochondrial proteome of these cells showed that the most affected proteins belonged to the OXPHOS system, mainly to the complexes that form supercomplexes or respirosomes (I, III, IV, and V). Defects in complex IV seemed to be due to assembly issues, which might prevent supercomplexes formation and efficient substrate channeling. It was also found that this mitochondriopathy affects other processes that are related to DNA genetic information flow (replication, transcription, and translation) as well as beta oxidation and tricarboxylic acid cycle. Conclusions: These data, as a whole, could be used for the better stratification of these diseases, as well as to optimize management and treatment options.

Resumen: Introducción: Las mitocondriopatías son enfermedades multisistémicas que afectan el funcionamiento de la fosforilación oxidativa (OXPHOS). Un buen modelo de estudio para estas enfermedades es el cultivo primario de fibroblastos. En este trabajo se utilizaron fibroblastos con mitocondriopatía del complejo IV para determinar cuáles son las principales funciones afectadas en esta enfermedad. Métodos: Se realizaron cultivos primarios de fibroblastos para corroborar el fenotipo de la enfermedad. Las mitocondrias se aislaron de estas células y se extrajo su proteoma para su identificación. Las proteínas identificadas se validaron con la base de datos de MitoMiner. Resultados: Los fibroblastos conservaron el fenotipo de la enfermedad que incluye un defecto del complejo IV. El proteoma mitocondrial de estas células mostró que las proteínas más afectadas pertenecen al sistema de OXPHOS, principalmente los complejos que forman supercomplejos o respirosomas (I, III, IV y V). El defecto en el complejo IV al parecer se debió a problemas de ensamblaje que pueden evitar la formación de los supercomplejos y la eficiente canalización de sustratos. También se observó que esta mitocondriopatía afecta otros procesos relacionados con el flujo de información genética del DNA (replicación, transcripción y traducción), así como con la beta oxidación y el ciclo de los ácidos tricarboxílicos (TCA). Conclusiones: En conjunto, estos datos podrían utilizarse para una mejor clasificación de estas enfermedades, así como para la optimización de las opciones de manejo y tratamiento.

Proteomic changes in a childhood acute lymphoblastic leukemia cell line during the adaptation to vincristine / Cambios en el proteoma de una línea celular de leucemia linfoblástica aguda infantil durante la adaptación a vincristina

Abstract: Introduction: Relapse occurs in approximately 20% of Mexican patients with childhood acute lymphoblastic leukemia (ALL). In this group, chemoresistance may be one of the biggest challenges. An overview of complex cellular processes like drug tolerance can be achieved with proteomic studies. Methods: The B-lineage pediatric ALL cell line CCRF-SB was gradually exposed to the chemotherapeutic vincristine until proliferation was observed at 6 nM, control cells were cultured in the absence of vincristine. The proteome from each group was analyzed by nanoHPLC coupled to an ESI-ion trap mass spectrometer. The identified proteins were grouped into over-represented functional categories with the PANTHER classification system. Results: We found 135 proteins exclusively expressed in the presence of vincristine. The most represented functional categories were: Toll receptor signaling pathway, Ras Pathway, B and T cell activation, CCKR signaling map, cytokine-mediated signaling pathway, and oxidative phosphorylation. Conclusions: Our study indicates that signal transduction and mitochondrial ATP production are essential during adaptation of leukemic cells to vincristine, these processes represent potential therapeutic targets.

Resumen: Introducción: Aproximadamente el 20% de los pacientes mexicanos con leucemia linfoblástica aguda (LLA) infantil presentan recaídas. En este grupo, la quimiorresistencia es uno de los principales desafíos. Los estudios proteómicos pueden dar un panorama general de procesos celulares complejos como la tolerancia a fármacos. Métodos: La línea celular de LLA de linaje B, CCRF-SB, fue expuesta de manera gradual al fármaco quimioterapéutico vincristina hasta observar proliferación celular en presencia de 6 nM, como control se cultivaron células en ausencia del fármaco. Se analizó el proteoma de cada grupo mediante nanoHPLC acoplado a un espectrómetro de masas de tipo trampa de iones. Las proteínas identificadas se agruparon en categorías funcionales sobre-representadas con el sistema de clasificación PANTHER. Resultados: Encontramos 135 proteínas expresadas exclusivamente en presencia de vincristina. Las categorías funcionales más representadas fueron la señalización asociada a los receptores tipo Toll, señalización dependiente de Ras, activación de células B y T, mapa de señalización CCKR, señalización mediada por citoquinas y la fosforilación oxidativa. Conclusiones: Nuestro estudio indica que la transducción de señales y la producción de ATP mitocondrial son procesos esenciales durante la adaptación de células leucémicas a vincristina por lo que estos procesos representan potenciales blancos terapéuticos.

Effect of initial pH of medium with potato wastewater and glycerol on protein, lipid and carotenoid biosynthesis by Rhodotorula glutinis

Background: Rhodotorula glutinis is capable of synthesizing numerous valuable metabolites with extensive potential industrial usage. This paper reports the effect of initial culture medium pH on growth and protein, lipid, and carotenoid biosynthesis by R. glutinis. Results: The highest biomass yield was obtained in media with pH 4.0­7.0, and the value after 72 h was 17.2­19.4 gd.w./L. An initial pH of the medium in the range of 4.0­7.0 has no significant effect on the protein (38.5­41.3 g/100 gd.w.), lipid (10.2­12.7 g/100 gd.w.), or carotenoid (191.7­202.9 µg/gd.w.) content in the biomass or on the profile of synthesized fatty acids and carotenoids. The whole pool of fatty acids was dominated by oleic (48.1­53.4%), linoleic (21.4­25.1%), and palmitic acids (13.0­15.8%). In these conditions, the yeast mainly synthesized torulene (43.5­47.7%) and ß-carotene (34.7­38.6%), whereas the contribution of torularhodin was only 12.1­16.8%. Cultivation in medium with initial pH 3.0 resulted in a reduction in growth (13.0 gd.w./L) and total carotenoid (115.8 µg/gd.w.), linoleic acid (11.5%), and torularhodin (4.5%) biosynthesis. Conclusion: The different values of initial pH of the culture medium with glycerol and deproteinized potato wastewater had a significant effect on the growth and protein, lipid, and carotenoid biosynthesis by R. glutinis.

Characterization of OAZ1 and its potential functions in goose follicular development

Background: Ornithine decarboxylase antizyme 1 (OAZ1) is an important regulator of polyamine synthesis and uptake. Our previous studies indicated that high OAZ1 expression in the ovaries of laying geese is responsible for poor egg production. In the present study, the molecular characterization of goose OAZ1 gene was analyzed, as well as the expression profile in various follicular tissues. Results: An 873-bp cDNA sequence of the OAZ1 gene (Accession No. KC845302) with a +1 frameshift site (+175T) was obtained. The sequence consisted of a 652-bp two overlapping open reading frames (a putative protein with 216 amino acids). The OAZ domain, OAZ signature and OAZ super family domain were prominent conserved regions among species. As the follicle size increased, OAZ1 abundance showed an increasing trend during follicular development, while it decreased during follicular regression. The level of OAZ1 mRNA expression was the lowest in the fifth largest preovulatory follicle, and was 0.65-fold compared to the small white follicle (P b 0.05). OAZ1 mRNA expression in the largest preovulatory and postovulatory follicle was 2.11- and 2.49-fold compared to the small white follicle, respectively (P b 0.05). Conclusions: The goose OAZ1 structure confirms that OAZ1 plays an important role in ornithine decarboxylase-mediated regulation of polyamine homeostasis. Our findings provide an evidence for a potential function of OAZ1 in follicular development, ovulation and regression.