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1.
Nat Aging ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987646

RESUMO

Emerging evidence suggests that neurological and other post-acute sequelae of COVID-19 can persist beyond or develop following SARS-CoV-2 infection. However, the long-term trajectories of cognitive change after a COVID-19 infection remain unclear. Here we investigated cognitive changes over a period of 2.5 years among 1,245 individuals aged 60 years or older who survived infection with the original SARS-CoV-2 strain in Wuhan, China, and 358 uninfected spouses. We show that the overall incidence of cognitive impairment among older COVID-19 survivors was 19.1% at 2.5 years after infection and hospitalization, evaluated using the Telephone Interview for Cognitive Status-40. Cognitive decline primarily manifested in individuals with severe COVID-19 during the initial year of infection, after which the rate of decline decelerated. Severe COVID-19, cognitive impairment at 6 months and hypertension were associated with long-term cognitive decline. These findings reveal the long-term cognitive trajectory of the disease and underscore the importance of post-infection cognitive care for COVID-19 survivors.

2.
Pediatr Res ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548969

RESUMO

BACKGROUND: Overnutrition in early life increases the risk of obesity and metabolic diseases. We investigated the effects and the window period of a curcumin (CUR) diet on postnatal overfed rats. METHODS: Male rats aged 3 days were randomly divided into normal litters (NL, 10 pups/litter) and small litters (SL, 3 pups/litter). After weaning (Week 3, W3), NL rats were fed a normal diet (NL) and SL rats were fed a normal diet (SL) or 2% CUR diet from weaning (W3) (SL-CURW13), beginning of puberty (W6) (SL-CURW16), or end of puberty (W8) (SL-CURW18) for 10 weeks. RESULTS: Body weight, glucose intolerance and hyperlipidemia in the SL rats were higher than in the NL rats, especially after puberty. After the CUR intervention, SL-CURW13 and SL-CURW16 rats showed lower body weight gain, adipose tissue weight and mRNA level of C/EBPα in SAT, along with higher mRNA levels of ß-catenin. There was no difference between SL and SL-CURW18 rats. Glucose tolerance, serum lipids and hepatic lipids recovered to normal in the SL-CURW13 rats, but only partially in the SL-CURW16 and SL-CURW18 rats. CONCLUSION: Prepuberty is a window period for CUR intervention to improve programmed outcomes in postnatal overfed rats. IMPACT: Overnutrition during the first 1000 days of life has persistent negative effects on metabolism. Strategies should be taken to prevent overnutrition in early life to reduce the risk of obesity and metabolic disease in later life. A small-litter rat model was utilized to simulate early-life overnutrition in humans. We investigated the different effects and critical period for curcumin intervention on postnatal overfed rats. Dietary curcumin intervention before puberty could effectively transform nutritional programming to reduce obesity and metabolic disorders caused by early-life overnutrition, and an earlier intervention might predict a better outcome.

3.
Brain Behav ; 13(12): e3309, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37968885

RESUMO

BACKGROUND: Premature infants are inevitably exposed to painful events, including repetitive procedures, inflammation, or mixed stimulation that may induce long-term behavioral outcomes. Here, we set up three neonatal painful models to investigate their long-term effect on somatosensation and cognition. METHODS: Three types of neonatal pain models in rat were set up. Rat pups were randomly assigned to four groups. The needling pain (NP) group received repetitive needle pricks on the paws from the day of birth (PD0) to postnatal day 7 (PD7) to mimic the diagnostic and therapeutic procedures. The inflammatory pain (IP) group received the injection of carrageenan into the left hindpaw at PD3 to induce IP in peripheral tissues. The mixed pain group received a combination of the NP and IP (NIP). The control (CON) group was untreated. We performed behavioral and biochemical testing of juvenile rats (PD21-PD26). RESULTS: The NIP group showed a longer hypersensitivity than the NP group, when given a secondary inflammatory stimulation. NP led to insensitivity to anxiety-causing stimuli and impairment of fear memory both aggravated by NIP. NP reduced the expression of synapse-related molecules (GluN1/PSD95/GFAP) in the medial prefrontal cortex, and NIP exacerbated this decrease. The corticosterone secretion in the NIP group increased after the behavioral task, compared with those in other three groups. CONCLUSION: A combination of NP with inflammation occurring in the neonatal period might aggravate the adverse effects of each on somatosensory and cognitive development of rats, the mechanism of which might be associated with the increase of corticosterone secretion and the dysregulation of synaptic molecules.


Assuntos
Corticosterona , Dor , Humanos , Animais , Ratos , Masculino , Animais Recém-Nascidos , Dor/psicologia , Cognição , Inflamação
4.
Mol Nutr Food Res ; 67(9): e2200336, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36825504

RESUMO

SCOPE: This study investigates the effect of epigallocatechin gallate (EGCG) on white and beige preadipocyte growth and explores the involvement of the miR-let-7a/HMGA2 pathway. METHODS AND RESULTS: 3T3-L1 and D12 cells are treated with EGCG. The effect of EGCG on cell proliferation and viability is evaluated, as well as microRNA (miRNA)-related signaling pathways. EGCG inhibits 3T3-L1 and D12 preadipocyte growth, upregulates miR-let-7a expression, and downregulates high-mobility group AT-hook 2 (HMGA2) mRNA and protein levels in a time- and dose-dependent manner. In addition, overexpression of miR-let-7a significantly inhibits the growth of 3T3-L1 and D12 cells and decreases HMGA2 mRNA and protein levels. MiR-let-7a inhibitor antagonizes the inhibitory effects of EGCG on the number and viability of 3T3-L1 and D12 cells. Furthermore, miR-let-7a inhibitor reverses the EGCG-induced increase in miR-let-7a expression levels and decrease in HMGA2 mRNA and protein levels. HMGA2 overexpression induces an increase in cell number and viability and antagonizes EGCG-suppressed cell growth and HMGA2 expression in 3T3-L1 and D12 preadipocytes. CONCLUSION: EGCG inhibits the growth of 3T3-L1 and D12 preadipocytes by modulating the miR-let-7a and HMGA2 pathways.


Assuntos
Catequina , MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Chá , Transdução de Sinais , Proliferação de Células , Catequina/farmacologia , RNA Mensageiro
6.
Biotechnol Biofuels Bioprod ; 15(1): 114, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36289497

RESUMO

BACKGROUND: Schizochytrium sp. is a heterotrophic, oil-producing microorganism that can efficiently produce lipids. However, the industrial production of bulk chemicals using Schizochytrium sp. is still not economically viable due to high-cost culture medium. Replacing glucose with cheap and renewable lignocellulose is a highly promising approach to reduce production costs, but Schizochytrium sp. cannot efficiently metabolize xylose, a major pentose in lignocellulosic biomass. RESULTS: In order to improve the utilization of lignocellulose by Schizochytrium sp., we cloned and functionally characterized the genes encoding enzymes involved in the xylose metabolism. The results showed that the endogenous xylose reductase and xylulose kinase genes possess corresponding functional activities. Additionally, attempts were made to construct a strain of Schizochytrium sp. that can effectively use xylose by using genetic engineering techniques to introduce exogenous xylitol dehydrogenase/xylose isomerase; however, the introduction of heterologous xylitol dehydrogenase did not produce a xylose-utilizing engineered strain, whereas the introduction of xylose isomerase did. The results showed that the engineered strain 308-XI with an exogenous xylose isomerase could consume 8.2 g/L xylose over 60 h of cultivation. Xylose consumption was further elevated to 11.1 g/L when heterologous xylose isomerase and xylulose kinase were overexpressed simultaneously. Furthermore, cultivation of 308-XI-XK(S) using lignocellulosic hydrolysates, which contained glucose and xylose, yielded a 22.4 g/L of dry cell weight and 5.3 g/L of total lipid titer, respectively, representing 42.7 and 30.4% increases compared to the wild type. CONCLUSION: This study shows that engineering of Schizochytrium sp. to efficiently utilize xylose is conducive to improve its utilization of lignocellulose, which can reduce the costs of industrial lipid production.

7.
Dev Neurobiol ; 82(6): 545-561, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945168

RESUMO

Although extensive and untreated pain that occurs during a critical developmental window may impair cognition later in life, environmental interventions early in life might promote cognition. However, the underlying mechanism is poorly understood. Our current study utilized a rat model of "repetitive needle pricks" from the day of birth (P0) to postnatal day 7 (P7) to mimic the painful experience of preterm neonates in the neonatal intensive care unit. Enriched environment (EE) during development period (from P15 to P70) was implemented as a nonpharmacological intervention approach. Electrophysiological recording, behavioral tests, and biochemical analysis were performed after the end of EE (between P71 and P80). The results showed neonatal repetitive pain resulted in a reduction in mechanical withdrawal thresholds by the von Frey test in P70 (p < .001). Furthermore, neonatal repetitive pain impaired spatial learning and memory (p < .05) and even led to dysfunction in fear memory (p < .01). In contrast, EE rescued neonatal pain-induced cognitive deficits and normalized hippocampal long-term potentiation in rats exposed to neonatal pain (p << .05). The beneficial effect of EE might be the improvements in hippocampal synaptic plasticity via upregulating neurotrophic factors and N-methyl-d-aspartate (NMDA) receptors in the hippocampus. Our findings provide evidence that early environmental intervention might be a safe strategy to overcome neurodevelopmental abnormalities in preterm infants who experienced multiple procedural painful events during the early critical period.


Assuntos
Recém-Nascido Prematuro , N-Metilaspartato , Animais , Cognição , Hipocampo , Humanos , Recém-Nascido , Fatores de Crescimento Neural/farmacologia , Plasticidade Neuronal/fisiologia , Dor , Ratos , Receptores de N-Metil-D-Aspartato
8.
Exp Biol Med (Maywood) ; 247(18): 1670-1679, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35894140

RESUMO

Green tea epigallocatechin gallate (EGCG) and microRNA (miRNA) molecules modulate obesity. Nevertheless, it is still unknown whether EGCG modulates fat cell growth via miRNA-related signaling. In this study, white preadipocytes were used to examine whether the antimitogenic effect of EGCG on fat cells is regulated by the miR-143/MAPK7 pathway. We showed that EGCG upregulated the levels of miR-143, but not miR-155, in 3T3-L1 preadipocytes. Moreover, EGCG downregulated MAPK7 mRNA and protein levels time- and dose-dependently. MAPK7 expression increased during 3T3-L1 cell proliferation. miR-143 overexpression in the absence of EGCG mimicked the effects of EGCG to suppress preadipocyte growth and MAPK7 expression, whereas knockdown of miR-143 antagonized the EGCG-altered levels of miR-143, MAPK7, and pERK1/2 and reversed the EGCG-inhibited cell growth. These findings suggest that EGCG inhibits 3T3-L1 cell growth via miR-143/MAPK7 pathway.


Assuntos
Catequina , MicroRNAs , Camundongos , Animais , Células 3T3-L1 , Chá , Catequina/farmacologia , MicroRNAs/genética , RNA Mensageiro
9.
JAMA Neurol ; 79(5): 509-517, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35258587

RESUMO

Importance: Determining the long-term impact of COVID-19 on cognition is important to inform immediate steps in COVID-19 research and health policy. Objective: To investigate the 1-year trajectory of cognitive changes in older COVID-19 survivors. Design, Setting, and Participants: This cohort study recruited 3233 COVID-19 survivors 60 years and older who were discharged from 3 COVID-19-designated hospitals in Wuhan, China, from February 10 to April 10, 2020. Their uninfected spouses (N = 466) were recruited as a control population. Participants with preinfection cognitive impairment, a concomitant neurological disorder, or a family history of dementia were excluded, as well as those with severe cardiac, hepatic, or kidney disease or any kind of tumor. Follow-up monitoring cognitive functioning and decline took place at 6 and 12 months. A total of 1438 COVID-19 survivors and 438 control individuals were included in the final follow-up. COVID-19 was categorized as severe or nonsevere following the American Thoracic Society guidelines. Main Outcomes and Measures: The main outcome was change in cognition 1 year after patient discharge. Cognitive changes during the first and second 6-month follow-up periods were assessed using the Informant Questionnaire on Cognitive Decline in the Elderly and the Telephone Interview of Cognitive Status-40, respectively. Based on the cognitive changes observed during the 2 periods, cognitive trajectories were classified into 4 categories: stable cognition, early-onset cognitive decline, late-onset cognitive decline, and progressive cognitive decline. Multinomial and conditional logistical regression models were used to identify factors associated with risk of cognitive decline. Results: Among the 3233 COVID-19 survivors and 1317 uninfected spouses screened, 1438 participants who were treated for COVID-19 (691 male [48.05%] and 747 female [51.95%]; median [IQR] age, 69 [66-74] years) and 438 uninfected control individuals (222 male [50.68%] and 216 female [49.32%]; median [IQR] age, 67 [66-74] years) completed the 12-month follow-up. The incidence of cognitive impairment in survivors 12 months after discharge was 12.45%. Individuals with severe cases had lower Telephone Interview of Cognitive Status-40 scores than those with nonsevere cases and control individuals at 12 months (median [IQR]: severe, 22.50 [16.00-28.00]; nonsevere, 30.00 [26.00-33.00]; control, 31.00 [26.00-33.00]). Severe COVID-19 was associated with a higher risk of early-onset cognitive decline (odds ratio [OR], 4.87; 95% CI, 3.30-7.20), late-onset cognitive decline (OR, 7.58; 95% CI, 3.58-16.03), and progressive cognitive decline (OR, 19.00; 95% CI, 9.14-39.51), while nonsevere COVID-19 was associated with a higher risk of early-onset cognitive decline (OR, 1.71; 95% CI, 1.30-2.27) when adjusting for age, sex, education level, body mass index, and comorbidities. Conclusions and Relevance: In this cohort study, COVID-19 survival was associated with an increase in risk of longitudinal cognitive decline, highlighting the importance of immediate measures to deal with this challenge.


Assuntos
COVID-19 , Disfunção Cognitiva , Idoso , COVID-19/epidemiologia , Cognição , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , SARS-CoV-2 , Sobreviventes
10.
J Tradit Chin Med ; 42(1): 122-131, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35294132

RESUMO

OBJECTIVE: To develop the best short form of constitution in Chinese medicine questionnaire (CCMQ) and evaluate its psychometric properties in Chinese population. METHODS: A total of 21 948 subjects were used to refine the short form. Correlation coefficient, exploratory factor analysis (EFA) and Cronbach's alpha coefficient were used to analyze and select items to form the short form. Separate sample of 205 subjects were collected to further evaluate the short from. EFA, confirmatory factor analysis (CFA), item-scale correlation, discriminant validity, internal consistency reliability and split-half reliability were carried out to evaluate the short form. RESULTS: The short form CCMQ included 26 items. Seven common factors of characteristic root > 1 were extracted to explain 58.488% of the total variation. Result of CFA was consistent with the 9-factors structure. The mean differences of Blood-stasis body constitution and Qi-stagnation body constitution had statistical significance in body mass index differentiation. Cronbach's alpha coefficient of short form CCMQ was 0.863. The split-half reliability of total scale was 0.813, and each scale was 0.568-0.770. The item-scale correlations ranged from 0.620-0.849. CONCLUSION: The short form CCMQ consisted of 26 items with good psychometric properties. The short form should be recommended for the measurement of health of Chinese population in any clinical trial.


Assuntos
Medicina Tradicional Chinesa , China , Análise Fatorial , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
11.
Biotechnol J ; 17(5): e2100470, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35072339

RESUMO

Schizochytrium sp. has received increasing attention as promising commercial resource for the sustainable production of lipids, due to their fast growth rate and high lipid content. However, the price of glucose represents a significant proportion of the total substrate cost. Therefore, in this study, the lignocellulosic hydrolysate of corn stover hydrolysate (CSH) was used as low-cost culture medium to replace glucose in Schizochytrium sp. fermentation. When Schizochytrium sp. HX-308 was fermented with 20% glucose from CSH and 80% of glucose from pure glucose, the lipid production reached 21.2 g L-1 , which is lower than that of using 100% of pure glucose. However, the shifts of fatty acid composition indicated that CSH has great potential to enhance the percentage of polyunsaturated fatty acids (PUFAs) in total lipids. However, as the second largest carbon source in CSH, xylose was not utilized by the Schizochytrium sp. HX-308, and further analysis showed that probably because it does not possess a functional xylulose kinase. In addition, the degradation products in lignocellulosic hydrolysate have a strong inhibitory effect on cell growth, so it is necessary to investigate the tolerance of Schizochytrium sp. HX-308 to degradation products. Here, the effects of five typical degradation products on the growth and lipid synthesis were further investigated. Schizochytrium sp. HX-308 showed good tolerance to furan derivatives and organic acids, but low tolerance to phenolic compounds. Furthermore, in order to improve the lipid accumulation using CSH, the two-stage fermentation strategy was developed, resulting in a 54.8% increase compared to that of the one-stage strategy. In summary, this study provides a reference for further fermentation engineering with cheap lignocellulosic biomass as substrate.


Assuntos
Estramenópilas , Zea mays , Ácidos Graxos Insaturados/metabolismo , Fermentação , Glucose/metabolismo , Estramenópilas/metabolismo , Xilose/metabolismo
12.
Crit Rev Food Sci Nutr ; 62(32): 8920-8934, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34120537

RESUMO

Owing to the important physiological functions, polyunsaturated fatty acids (PUFAs) play a vital role in protecting human health, such as preventing cancer, cardiovascular disease, and diabetes. Specifically, Yarrowia lipolytica has been identified as the most popular non-conventional oleaginous yeast, which can accumulate the abundant intracellular lipids, indicating that has great potential as an industrial host for production of PUFAs. Notably, some novel engineering strategies have been applied to endow and improve the abilities of Y. lipolytica to synthesize PUFAs, including construction and optimization of PUFAs biosynthetic pathways, improvement of preucrsors acetyl-coA and NADPH supply, inhibition of competing pathways, knockout of ß-oxidation pathways, regulation of oxidative stress defense pathways, and regulation of genes involved in upstream lipid metabolism. Besides, some bypass approaches, such as strain mating, evolutionary engineering, and computational model based on omics, also have been proposed to improve the performance of engineering strains. Generally, in this review, we summarized the recent advances in engineering strategies and bypass approaches for improving PUFAs production by Y. lipolytica. In addition, we further summarized the latest efforts of CRISPR/Cas genome editing technology in Y. lipolytica, which is aimed to provide its potential applications in PUFAs production.


Assuntos
Yarrowia , Humanos , Yarrowia/genética , Yarrowia/metabolismo , Engenharia Metabólica , Biotecnologia , Ácidos Graxos Insaturados/metabolismo , Edição de Genes , Ácidos Graxos/metabolismo
13.
Crit Rev Biotechnol ; 42(6): 838-855, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34779326

RESUMO

Eicosapentaenoic Acid (EPA) is an essential ω-3 polyunsaturated fatty acid for human health. Currently, high-quality EPA production is largely dependent on the extraction of fish oil, but this unsustainable approach cannot meet its rising market demand. Biotechnological approaches for EPA production from microorganisms have received increasing attention due to their suitability for large-scale production and independence of the seasonal or climate restrictions. This review summarizes recent research on different microorganisms capable of producing EPA, such as microalgae, bacteria, and fungi, and introduces the different EPA biosynthesis pathways. Notably, some novel engineering strategies have been applied to endow and improve the abilities of microorganisms to synthesize EPA, including the construction and optimization of the EPA biosynthesis pathway, an increase in the acetyl-CoA pool supply, the increase of NADPH and the inhibition of competing pathways. This review aims to provide an updated summary of EPA production.


Assuntos
Ácidos Graxos Ômega-3 , Microalgas , Vias Biossintéticas , Ácido Eicosapentaenoico/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Engenharia Metabólica , Microalgas/metabolismo
14.
Front Cell Infect Microbiol ; 11: 597431, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34671567

RESUMO

A close relationship between knee osteoarthritis (KOA) and gut microbiota has recently been described. Herein, we aim to investigate the effect of electroacupuncture (EA) on gut microbiota in participants with KOA. We conducted a study of 60 participants with KOA and 30 matched healthy controls (HCs). Sixty participants were allocated to either EA group (n=30) or sham acupuncture (SA) group (n=30). Five obligatory acupoints and three adjunct acupoints were punctured in the EA group. Eight non-acupoints that were separated from conventional acupoints or meridians were used for the SA group. Participants in both groups received 24 sessions within eight weeks. Fecal microbial analyses by 16S ribosomal RNA gene sequencing were carried out after collecting stools at T0 and T8 weeks (Four samples with changed defecation habits were excluded). The results showed that both Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score (P=0.043) and NRS score (P=0.002) decreased more in EA group than those in SA group. Moreover, EA could reverse more KOA-related bacteria including Bacteroides, [Eubacterium]_hallii_group, Agathobacter and Streptococcus. The number of significantly different genera between KOA patients and HCs were less after EA treatment than that after SA treatment. This meant that EA modified the composition of the gut microbiome, making it closer to healthy people, while not significantly affecting the microbial diversity. Two genera including Agathobacter (P=0.0163), Lachnoclostridium (P=0.0144) were statistically increased than baseline in EA group (paired Wilcoxon rank sum test). After EA treatment, Bacteroides (P=0.0394) was more abundant and Streptococcus (P=0.0306) was significantly reduced in patients who demonstrated adequate response than in those with inadequate response (Wilcoxon rank-sum test). Spearman correlation test between gut microbe and KOA clinical outcomes indicated that Bacteroides and Agathobacter was negatively correlated with NRS score, WOMAC total score, and WOMAC pain, stiffness and pain scores (P<0.001 or 0.05 or 0.01), while Streptococcus was positively correlated with them (P<0.05 or 0.01). Our study suggests that EA contributes to the improvement of KOA and gut microbiota could be a potential therapeutic target.


Assuntos
Terapia por Acupuntura , Eletroacupuntura , Microbioma Gastrointestinal , Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/terapia , Resultado do Tratamento
15.
Appl Microbiol Biotechnol ; 105(12): 4919-4930, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34125275

RESUMO

Terpenoids represent one of the largest class of chemicals in nature, which play important roles in food and pharmaceutical fields due to diverse biological and pharmacological activities. Microorganisms are recognized as a promising source of terpenoids due to its short growth cycle and sustainability. Importantly, microalgae can fix inorganic carbon through photosynthesis for the growth of themselves and the biosynthesis of various terpenoids. Moreover, microalgae possess effective biosynthesis pathways of terpenoids, both the eukaryotic mevalonic acid (MVA) pathway and the prokaryotic methyl-D-erythritol 4-phosphate (MEP) pathway. In recent years, various genetic engineering strategies have been applied to increase target terpenoid yields, including overexpression of the rate-limited enzymes and inhibition of the competing pathways. However, since gene-editing tools are only built in some model microalgae, fermentation strategies that are easier to be operated have been widely successful in promoting the production of terpenoids, such as changing culture conditions and addition of chemical additives. In addition, an economical and effective downstream process is also an important consideration for the industrial production of terpenoids, and the solvent extraction and the supercritical fluid extraction method are the most commonly used strategies, especially in the industrial production of ß-carotene and astaxanthin from microalgae. In this review, recent advancements and novel strategies used for terpenoid production are concluded and discussed, and new insights to move the field forward are proposed. KEY POINTS: • The MEP pathway is more stoichiometrically efficient than the MVA pathway. • Advanced genetic engineering and fermentation strategies can increase terpene yield. • SFE has a higher recovery of carotenoids than solvent extraction.


Assuntos
Microalgas , Terpenos , Vias Biossintéticas , Carotenoides , Engenharia Metabólica , Ácido Mevalônico
16.
Appl Microbiol Biotechnol ; 105(10): 3873-3882, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33907890

RESUMO

Saccharomyces cerevisiae is a widely used microorganism and a greatly popular cell factory for the production of various chemicals. In order to improve the yield of target chemicals, it is often necessary to increase the copy numbers of key genes or engineer the related metabolic pathways, which traditionally required time-consuming repetitive rounds of gene editing. With the development of gene-editing technologies such as meganucleases, TALENs, and the CRISPR/Cas system, multiplex genome editing has entered a period of rapid development to speed up cell factory optimization. Multi-copy insertion and removing bottlenecks in biosynthetic pathways can be achieved through gene integration and knockout, for which multiplexing can be accomplished by targeting repetitive sequences and multiple sites, respectively. Importantly, the development of the CRISPR/Cas system has greatly increased the speed and efficiency of multiplex editing. In this review, the various multiplex genome editing technologies in S. cerevisiae were summarized, and the principles, advantages, and the disadvantages were analyzed and discussed. Finally, the practical applications and future prospects of multiplex genome editing were discussed. KEY POINTS: • The development of multiplex genome editing in S. cerevisiae was summarized. • The pros and cons of various multiplex genome editing technologies are discussed. • Further prospects on the improvement of multiplex genome editing are proposed.


Assuntos
Edição de Genes , Saccharomyces cerevisiae , Sistemas CRISPR-Cas , Saccharomyces cerevisiae/genética
17.
J Agric Food Chem ; 69(8): 2367-2381, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33595318

RESUMO

Terpenoids are an important class of secondary metabolites that play an important role in food, agriculture, and other fields. Microorganisms are rapidly emerging as a promising source for the production of terpenoids. As an oleaginous yeast, Yarrowia lipolytica contains a high lipid content which indicates that it must produce high amounts of acetyl-CoA, a necessary precursor for the biosynthesis of terpenoids. Y. lipolytica has a complete eukaryotic mevalonic acid (MVA) pathway but it has not yet seen commercial use due to its low productivity. Several metabolic engineering strategies have been developed to improve the terpenoids production of Y. lipolytica, including developing the orthogonal pathway for terpenoid synthesis, increasing the catalytic efficiency of terpenoids synthases, enhancing the supply of acetyl-CoA and NADPH, expressing rate-limiting genes, and modifying the branched pathway. Moreover, most of the acetyl-CoA is used to produce lipid, so it is an effective strategy to strike a balance of precursor distribution by rewiring the lipid biosynthesis pathway. Lastly, the latest developed non-homologous end-joining strategy for improving terpenoid production is introduced. This review summarizes the status and metabolic engineering strategies of terpenoids biosynthesis in Y. lipolytica and proposes new insights to move the field forward.


Assuntos
Yarrowia , Acetilcoenzima A , Engenharia Metabólica , Ácido Mevalônico , Terpenos , Yarrowia/genética
18.
Biotechnol Bioeng ; 118(1): 153-163, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32897579

RESUMO

Escherichia coli BL21 (DE3) is an excellent and widely used host for recombinant protein production. Many variant hosts were developed from BL21 (DE3), but improving the expression of specific proteins remains a major challenge in biotechnology. In this study, we found that when BL21 (DE3) overexpressed glucose dehydrogenase (GDH), a significant industrial enzyme, severe cell autolysis was induced. Subsequently, we observed this phenomenon in the expression of 10 other recombinant proteins. This precludes a further increase of the produced enzyme activity by extending the fermentation time, which is not conducive to the reduction of industrial enzyme production costs. Analysis of membrane structure and messenger RNA expression analysis showed that cells could underwent a form of programmed cell death (PCD) during the autolysis period. However, blocking three known PCD pathways in BL21 (DE3) did not completely alleviate autolysis completely. Consequently, we attempted to develop a strong expression host resistant to autolysis by controlling the speed of recombinant protein expression. To find a more suitable protein expression rate, the high- and low-strength promoter lacUV5 and lac were shuffled and recombined to yield the promoter variants lacUV5-1A and lac-1G. The results showed that only one base in lac promoter needs to be changed, and the A at the +1 position was changed to a G, resulting in the improved host BL21 (DE3-lac1G), which resistant to autolysis. As a consequence, the GDH activity at 43 h was greatly increased from 37.5 to 452.0 U/ml. In scale-up fermentation, the new host was able to produce the model enzyme with a high rate of 89.55 U/ml/h at 43 h, compared to only 3 U/ml/h achieved using BL21 (DE3). Importantly, BL21 (DE3-lac1G) also successfully improved the production of 10 other enzymes. The engineered E. coli strain constructed in this study conveniently optimizes recombinant protein overexpression by suppressing cell autolysis, and shows great potential for industrial applications.


Assuntos
RNA Polimerases Dirigidas por DNA/biossíntese , Regulação para Baixo , Escherichia coli , Expressão Gênica , Vetores Genéticos , Regiões Promotoras Genéticas , Proteínas Virais/biossíntese , RNA Polimerases Dirigidas por DNA/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Virais/genética
19.
Zhonghua Nan Ke Xue ; 27(11): 1017-1024, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-37422875

RESUMO

Objective: To analyze the academic thought, medication experience and prescription rules of Academician Wang Qi in the treatment of premature ejaculation (PE) using the TCM inheritance support platform (V2.5). METHODS: We collected and sorted out the medical records on the treatment of PE from Academician Wang Qi's Clinic. We established a database of medical records on the TCM inheritance support platform, analyzed the drugs and prescriptions in the database and explored new prescriptions using "statistical reports" and "data analysis" systems on the platform. RESULTS: A total of 91 effective prescriptions were recorded, involving 148 TCM drugs, with Phellodendron, Amomum Villosum, Polygala Tenuifolia, Tuckahoe, Lodestone, Oyster, Acanthopanax Senticosus, Uncaria, Tribulus, and Keel as the top 10 with the highest frequency of use, which were featured mainly by "warm" and "cold" concerning the four natures, "sweet", "bitter" and "pungent" relating to the five flavors, and acting on "kidney meridian", "liver meridian" and "heart meridian" in terms of the meridian tropisms. In addition, 5 new prescriptions were obtained through unsupervised entropy hierarchical clustering. CONCLUSIONS: In the treatment of PE, Academician Wang Qi employs tranquilizing the mind and consolidating the kidney (An Zhi Gu Shen) as the primary strategy, taking into account the three organs of heart, liver and kidneys, focusing on the phase of calming the mind or regulating the liver or clearing the kidney or controlling fire, and adding or reducing drugs according to different conditions and syndromes, which conforms to his diagnosis and treatment mode of "body differentiation-disease differentiation-syndrome differentiation". The analysis of the potential new prescriptions also accords with Academician Wang Qi's rules of medication, which can provide some ideas for the clinical treatment of and scientific researches on premature ejaculation in the future.

20.
Front Neurosci ; 14: 722, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733201

RESUMO

Preterm infants in neonatal intensive care units are inevitably subjected to numerous painful procedures. However, little is known about the consequences of early pain experience on fear memory formation later in life. We hypothesized that exposure to repetitive pain in early life triggered hippocampal synaptic plasticity and resulted in memory deficiency in prepubertal and adult rats. From the day of birth (P0) to postnatal day 7 (P7), neonatal male rat pups were randomly assigned to either needle pricks or tactile touches repetitively every 6 h. Trace fear conditioning was performed on rats on P24-P26 and P87-P89. On P24 and P87, rats were sacrificed for molecular and electrophysiological studies. On P24-26 and P87-89, rats that experienced neonatal needle treatment showed a significant reduction in freezing time in the contextual fear conditioning (P < 0.05) and trace fear conditioning tests (P < 0.05). Moreover, repetitive neonatal procedural pain caused a significant decrease in the magnitude of hippocampal long-term potentiation induced by high-frequency stimulation. Furthermore, rats that experienced neonatal needle treatment demonstrated sustained downregulation of NR1, NR2A, NR2B, and GluR1 expression in the hippocampus. Therefore, neonatal pain is related to deficits in hippocampus-related fear memory later in life and might be caused by impairments in hippocampal synaptic plasticity.

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