The recent advance and prospect of natural source compounds for the treatment of heart failure.

Heart failure is a continuously developing syndrome of cardiac insufficiency caused by diseases, which becomes a major disease endangering human health as well as one of the main causes of death in patients with cardiovascular diseases. The occurrence of heart failure is related to hemodynamic abnormalities, neuroendocrine hormones, myocardial damage, myocardial remodeling etc, lead to the clinical manifestations including dyspnea, fatigue and fluid retention with complex pathophysiological mechanisms. Currently available drugs such as cardiac glycoside, diuretic, angiotensin-converting enzyme inhibitor, vasodilator and ß receptor blocker etc are widely used for the treatment of heart failure. In particular, natural products and related active ingredients have the characteristics of mild efficacy, low toxicity, multi-target comprehensive efficacy, and have obvious advantages in restoring cardiac function, reducing energy disorder and improving quality of life. In this review, we mainly focus on the recent advance including mechanisms and active ingredients of natural products for the treatment of heart failure, which will provide the inspiration for the development of more potent clinical drugs against heart failure.

Efficacy and safety of autologous chondrocyte implantation for osteochondral defects of the talus: a systematic review and meta-analysis.

INTRODUCTION: Studies have reported various effects of autologous chondrocyte implantation (ACI) on osteochondral defects of the talus. Therefore, to assess the effectiveness of ACI for osteochondral defects of the talus, we used the meta-analytic approach. MATERIALS AND METHODS: Electronic databases PubMed, Embase, and the Cochrane Library were systematically searched to identify eligible studies from their inception until November 2020. The random-effects model was used to calculate the incidence of success rate and American Orthopaedic Foot and Ankle Society (AOFAS) score for patients after ACI treatment. Subgroup analyses were also conducted based on age, technique, indication, size, and follow-up duration. RESULTS: For the final meta-analysis, we selected 23 case series studies with a total of 458 patients with osteochondral defects of the talus. Overall, after ACI for patients with osteochondral defects of the talus, we noted that the incidence of success rate was 89% (95% confidence interval (95% CI) 85%-92%; P < 0.001). Moreover, after ACI for patients with osteochondral defects of the talus, the AOFAS score was 86.33 (95% CI 83.33-89.33; P < 0.001). Subgroup analysis showed that the AOFAS score after ACI is significantly different when stratified by the mean age of the patients (P = 0.006). CONCLUSIONS: This study revealed that the use of ACI could provide a relatively high success rate and improve the AOFAS score for patients with osteochondral defects of the talus, which should be recommended in clinical practice.

Glutamate as a non-conventional substrate for high production of the recombinant protein in Escherichia coli.

The economic viability of the biomass-based biorefinery is readily acknowledged by implementation of a cascade process that produces value-added products such as enzymes prior to biofuels. Proteins from the waste stream of biorefinery processes generally contain glutamate (Glu) in abundance. Accordingly, this study was initiated to explore the potential of Glu for production of recombinant proteins in Escherichia coli. The approach was first adopted by expression of D-hydantoinase (HDT) in commercially-available BL21(DE3) strain. Equipped with the mutant gltS (gltS*), the strain grown on Glu produced the maximum HDT as compared to the counterpart on glucose, glycerol, or acetate. The Glu-based production scheme was subsequently reprogrammed based on the L-arabinose-regulated T7 expression system. The strain with gltS* was further engineered by rewiring metabolic pathways. With low ammonium, the resulting strain produced 1.63-fold more HDT. The result indicates that Glu can serve as a carbon and nitrogen source. Overall, our proposed approach may open up a new avenue for the enzyme biorefinery platform based on Glu.

MDH1 and MDH2 Promote Cell Viability of Primary AT2 Cells by Increasing Glucose Uptake.

Background: Acute lung injury (ALI) is a clinical disease with high morbidity and mortality, with limited treatment means. For primary alveolar epithelial type II (AT2) cells, glycolysis is an essential bioenergetic process. However, the significance of AT2 cell glycolysis in sepsis ALI remains unknown. Methods and Results: In the current study, based on microarray analysis, real-time quantitative PCR, and Western blotting, we found that the hsa00020: citrate cycle pathway was inactivated, specifically its downstream gene: malate dehydrogenase 1 (MDH1) and MDH2 in ALI. In this context, lipopolysaccharides (LPS) were used to construct the septic-ALI mouse model and the biological function of MDH1 and MDH2 in primary alveolar epithelial type II (AT2) cells was explored. Through CCK-8, EdU, transwell, and apoptosis assays, we found that MDH1 and MDH2 promoted the cell vitality of AT2 cells, which relied on MDH1 and MDH2 to promote the glucose intake of AT2 cells. Conclusion: Overall, these findings suggest that targeting MDH1/MDH2-mediated AT2 cell glycolysis may be a potential strategy for ALI patients.

Medicinal and edible plants in the treatment of dyslipidemia: advances and prospects.

Dyslipidemia is an independent risk factor of cardiovascular diseases (CVDs), which lead to the high mortality, disability, and medical expenses in the worldwide. Based on the previous researches, the improvement of dyslipidemia could efficiently prevent the occurrence and progress of cardiovascular diseases. Medicinal and edible plants (MEPs) are the characteristics of Chinese medicine, and could be employed for the disease treatment and health care mostly due to their homology of medicine and food. Compared to the lipid-lowering drugs with many adverse effects, such as rhabdomyolysis and impaired liver function, MEPs exhibit the great potential in the treatment of dyslipidemia with high efficiency, good tolerance and commercial value. In this review, we would like to introduce 20 kinds of MEPs with lipid-lowering effect in the following aspects, including the source, function, active component, target and underlying mechanism, which may provide inspiration for the development of new prescription, functional food and complementary therapy for dyslipidemia.

Corrigendum: The Depression Anxiety Stress Scale-21 in Chinese Hospital Workers: Reliability, Latent Structure, and Measurement Invariance Across Genders.

[This corrects the article DOI: 10.3389/fpsyg.2020.00247.].

Bibliometric Analysis of Birt-Hogg-Dubé Syndrome From 2001 to 2021.

Background: Birt-Hogg-Dubé syndrome (BHD) is a rare autosomal dominant inherited disorder caused by germline mutations in folliculin (FLCN). Despite our significantly evolved understanding of BHD over the past decades, no bibliometric analyses have been conducted in this field. This study aimed to analyze and visualize the characteristics of publication outputs, the research hotspots, and scientific frontiers about BHD using bibliometric analysis. Methods: All relevant literature on BHD was culled from the Web of Science Core Collection (WoSCC) database. Valid data were extracted from the articles and visually analyzed using CiteSpace and VOSviewer. Results: A total of 751 qualifying papers were included. Publication outputs concerning BHD increased over time. The dominant position of the United States and Japan in BHD research field was evident. National Cancer Institute (the USA) and Yokohama City University (Japan) were the two most productive organizations. W. Marston Linehan exerted a considerable publication impact and had made the most remarkable contributions in the field of BHD. Plos One was the journal with the highest publication outputs, and half of the top 10 journals and co-cited journals belonged to Q1 or Q2. Keyword citation bursts revealed that management, tumor suppressor, flcn gene, spectrum, diagnosis, risk, computed tomography were the emerging research hotspots. Conclusion: Research on BHD is prosperous. International cooperation between countries and organizations is also expected to deepen and strengthen in the future. Our results indicated that FLCN-associated pathways involved in the pathogenesis of BHD, specific options for early diagnosis, and molecular-targeting therapies will remain research hotspots in the future.

Ankle joint pressure change before and after subtalar joint arthrodesis in varus and valgus malalignment of the tibia.

Purpose: The compensation mechanism of subtalar joint in ankle with varus or valgus deformity is controversial and not well established. This biomechanical study aims to investigate how subtalar joint arthrodesis will affect the ankle joint pressure in varus and valgus malalignment of the tibia. Methods: Eight fresh-frozen human cadaver legs were tested in this study. A custom-made fixture was utilized and a total of 600N was applied to simulate weight-bearing. Intra-articular sensors (TeckScan) were inserted in the ankle joint to demonstrate the ankle joint pressure. Conditions include: Neutral, 5°, 10°, 15° and 20° varus, 5°, 10°, 15° and 20° valgus. Results: After the fusion of the subtalar joint, when the tibia is gradually inverted, the inside pressure of the ankle joint gradually increases, and the pressure on the outside of the ankle joint gradually decreases. When the tibia is gradually eversion, the pressure on the outside of the ankle joint gradually increases, and the inside of the ankle joint gradually decreases. Conclusions: After the subtalar joint is fused, the compensatory activity of the subtalar joint disappears, and the regulation of the pressure in the ankle joint will be lost. We hypothesized that the inversion compensation of the subtalar joint is more likely to occur than the eversion compensation.

Implication of VEGFR2 Polymorphism on the Prognosis of Anlotinib Monotherapy for Patients With Treatment-Refractory Advanced NSCLC: An Exploratory Study.

Background: This study aimed to investigate the implication of Vascular Endothelial Growth Factor Receptor 2 (VEGFR2) polymorphism on the prognosis of anlotinib monotherapy among patients with treatment-refractory advanced nonsmall cell lung cancer (NSCLC). Methods: Designed as a retrospective study, this study included a total of 129 patients with treatment-refractory advanced NSCLC who were administered with anlotinib monotherapy. The efficacy of the patients was assessed regularly. The prognosis was performed and adverse reactions during anlotinib administration were collected. Available and appropriate biological specimens of the 129 patients were collected to perform VEGFR2 polymorphism analysis and VEGFR2 gene mRNA expression analysis accordingly. Association analysis between genotype status of VEGFR2 polymorphism and other variables was implemented in univariate and multivariate analysis. Results: Efficacy data indicated that the objective response rate (ORR) and disease control rate (DCR) of the 129 patients with NSCLC who received anlotinib monotherapy was 9.3% (95% CI: 4.9%-15.7%) and 78.3% (95%CI: 70.2%-85.1%), respectively. Additionally, prognostic data suggested that the median progression-free survival (PFS) and overall survival (OS) of the 129 patients with NSCLC were 4.1 months (95%CI: 2.84-5.36) and 10.1 months (95%CI: 8.58-11.62), respectively. Furthermore, polymorphism analysis indicated that polymorphism of 4397T>C in VEGFR2 was of clinical significance in the exploratory analysis, which exhibited that the median PFS of patients with TC/CC and TT genotype of 4397T>C polymorphism were 2.8 and 5.0 months, respectively (P = .009). Additionally, patients with TT genotype conferred a superior OS compared with those with TC/CC genotype (median OS: 11.5 vs 7.3 months, P = .016). Interestingly, mRNA expression of the VEGFR2 gene suggested that mRNA expression of VEGFR2 in PBMC specimens of patients with TC/CC genotype was significantly higher than that of patients with TT genotype (P < .001). Conclusion: Anlotinib monotherapy exhibited potential efficacy for patients with treatment-refractory advanced NSCLC. VEGFR2 polymorphism 4397T>C might be used as a promising biomarker to predict the survival of patients with NSCLC who received anlotinib administration.

Effect of α-tocopherol in alleviating the lipopolysaccharide-induced acute lung injury via inhibiting nuclear factor kappa-B signaling pathways.

Acute respiratory distress syndrome (ARDS) leads to the acute lung injury (ALI), a form of diffused alveolars injury, accompanied by severe inflammation and oxidative damage of alveolar epithelial cells. α-Tocopherol (α-TOH), one of the eight isoforms of vitamin E, is a natural antioxidant-free radical. We aimed to understand the effect of α-TOH and mechanism involved in inducing the ALI. Lipopolysaccharide (LPS) is injected into the trachea of mice to generate ALI mouse models. α-TOH was used to administrate the mice intragastrically to detect the expression of inflammatory factors and antioxidant molecules by enzyme linked immunosorbent assay, hematoxylin-eosin staining and immunohistochemical staining. Mouse alveolar epithelial cell line (MLE-12 cells) was used to determine the effect of α-TOH on alveolar epithelial cells. Inflammatory factors such as, interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α shows significant increase in the lung tissues of the mice induced by LPS and reduction in the expressions of superoxide dismutase (SOD)1/2 and glutathione peroxidase (GSH-Px). After treatment with α-TOH, the inflammation and oxidative stress levels shows substantial reduction in the lung tissues of the mice. Moreover, α-TOH also increases the proliferation ability of MLE-12 cells in vitro and reduces apoptosis level. In addition, α-TOH reduces p65 phosphorylation and nuclear translocation in alveolar epithelial cells in vivo and in vitro, thus, inhibiting the activity of the nuclear factor kappa-B (NF-κB) signaling pathway. α-TOH reduces the inflammation and oxidative stress of lung tissue by inhibiting the NF-κB signaling pathway, thereby alleviating the LPS-induced ALI.

Isoorientin suppresses sepsis-induced acute lung injury in mice by activating an EPCR-dependent JAK2/STAT3 pathway.

Sepsis is a systemic inflammatory syndrome, and acute lung injury (ALI) is one of the most common fatal complications of sepsis. Isoorientin (ISO) exerts a momentous role in the regulation of inflammation. However, whether ISO has a protective effect on sepsis-induced ALI remains unknown. This research aimed to elucidate the function of ISO on sepsis-induced ALI and its mechanism. In this study, the sepsis-induced ALI was established in the male C57BL/6 J mice. Functionally, ISO reduced the total protein concentration in BALF, lung wet/dry ratio and the numbers of neutrophils and macrophages in BALF as well as ameliorated lung injury. Besides, ISO treatment decreased the cytokine expressions and oxidative stress, and repressed the adhesion and migration of inflammatory cells induced by CLP. Mechanistically, ISO reduced the shedding of EPCR in the endothelial cell membrane; ISO treatment activated the JAK2/STAT3 signaling pathway through EPCR and the JAK2/STAT3 pathway inhibitors repressed the anti-inflammatory and antioxidant effects of ISO. In general, ISO suppressed sepsis-induced ALI in mice by activating an EPCR-dependent JAK2/STAT3 pathway.

[Comparison of Four-hook Needle and Memory Alloy Coil 
in Localization of Pulmonary Nodules].

BACKGROUND: With the extensive development of minimally invasive surgery for pulmonary nodules, preoperative localization becomes more and more critical. There are some defects in traditional localization methods, so it is necessary to improve. The aim of this study was to compare and analyze the safety and effectiveness of two new methods, namely four-hook needle and memory alloy coil, in the localization of pulmonary nodules. METHODS: A retrospective analysis of 152 patients was performed. 76 cases were in four-hook needle group, and 76 cases were in memory alloy coil group. Pulmonary nodules were located before operation, and then video-assisted wedge resection was performed. The average procedure time, localization complications and nodule resection time were counted. RESULTS: The target pulmonary nodules were successfully removed in both groups. In four-hook needle group, 76 patients found localization devices, all the pulmonary nodules were successfully removed, and one case was transferred to open the chest for wedge resection of pulmonary nodules due to severe thoracic adhesion. All 76 patients in memory alloy coil group were successfully resected with pulmonary nodules, and one patient underwent compromising enlarged resection because no lesion was found after the specimen was removed during the operation. There was no significant difference in the incidence of pneumothorax and pulmonary hemorrhage, the success rate of localization and nodule wedge resection time between the two groups. The average time of localization in four-hook needle group was (13.66±3.11) min, lower than that of memory alloy coil group (15.51±3.65) min, and the difference was statistically significant (P=0.001). In memory alloy coil group, when the distance from the nodule to the pleura was ≥1.5 cm and <1.5 cm, the average localization time was (17.20±4.46) min and (14.91±3.15) min, respectively, and there was a statistical difference between the two distance (P=0.044). CONCLUSIONS: Four-hook needle and memory alloy coil have good safety and effectiveness, and the localization time of four-hook needle is shorter. When using memory alloy coil, the effect of the method is better for pulmonary nodules with a distance less than 1.5 cm to pleura.

Osteopontin isoform c promotes the survival of cisplatin-treated NSCLC cells involving NFATc2-mediated suppression on calcium-induced ROS levels.

BACKGROUND: Tumor microenvironment (TME) critically contributed to the malignant progression of transformed cells and the chemical responses to chemotherapy reagents. Osteopontin (OPN) is a secretory onco-protein with several splicing isoforms, all of which were known to regulate tumor growth and able to alter cell-cell or cell-TME communication, however, the exact role and regulation of the OPN splicing isoforms was not well understood. METHODS: In this study, the effects of conditioned medium from the culture of OPN splicing isoforms overexpressing cells on cell functions were evaluated. The methods of nuclear calcium reporter assays and subcellular distribution of nuclear factor of activated T cells c2 (NFATc2) assays were used to investigate the molecular mechanism underlining the roles of OPN splicing isoforms. RESULTS: We found that the survival of NSCLC cells treated with cisplatin was increased by secretory OPNc in the condition medium, where reduction of apoptosis by OPNc was associated with the activation of cellular calcium signals and subsequent nuclear translocation of NFATc2. CONCLUSIONS: The results revealed a mechanism of OPN and downstream signal for tumor cells to survive in chemo-stressed TME, which emphasized the importance of secretory proteins in alternative splicing isoforms. Our study not only demonstrated the importance of OPN neutralization for anti-tumor effects, but also implied that modulation in calcium/NFATc2/ROS axis could be a novel approach for improving the long-term outcome of NSCLC treatment.

Fullerol-hydrogel microfluidic spheres for in situ redox regulation of stem cell fate and refractory bone healing.

The balance of redox homeostasis is key to stem cell maintenance and differentiation. However, this balance is disrupted by the overproduced reactive oxygen species (ROS) in pathological conditions, which seriously impair the therapeutic efficacy of stem cells. In the present study, highly dispersed fullerol nanocrystals with enhanced bioreactivity were incorporated into hydrogel microspheres using one-step innovative microfluidic technology to construct fullerol-hydrogel microfluidic spheres (FMSs) for in situ regulating the redox homeostasis of stem cells and promoting refractory bone healing. It was demonstrated that FMSs exhibited excellent antioxidant activity to quench both intracellular and extracellular ROS, sparing stem cells from oxidative stress damage. Furthermore, these could effectively promote the osteogenic differentiation of stem cells with the activation of FoxO1 signaling, indicating the intrinsically osteogenic property of FMSs. By injecting the stem cells-laden FMSs into rat calvarial defects, the formation of new bone was remarkably reinforced, which is a positive synergic effect from modulating the ROS microenvironment and enhancing the osteogenesis of stem cells. Collectively, the antioxidative FMSs, as injectable stem cell carriers, hold enormous promise for refractory bone healing, which can also be expanded to deliver a variety of other cells, targeting diseases that require in situ redox regulation.

Osteotomy combined with lateral ligament reconstruction in treating osteochondral lesion in patients with talar injury and varus ankle.

ABSTRACT: This study aimed to investigate the therapeutic effects of osteotomy combined with lateral ligament reconstruction on the osteochondral lesion of patients with talar injuries and varus ankles.Seventy five patients with talar injuries and varus ankles who received osteotomy combined with lateral ligament reconstruction for the osteochondral lesions from June 2008 to December 2014 were retrospectively reviewed. Patients were followed up for 32.4 ±â€Š15.3 months after surgeries, and the AOFAS-AH score, VAS score and SF36 score were determined preoperatively and postoperatively. The iconographic data were compared preoperatively and postoperatively, including tibial anterior surface angle (TAS), TTS, TT, and tibial lateral surface angle (TLS) angles.After surgeries, the AOFAS-AF score increased from 43.2 ±â€Š8.1 to 82.1 ±â€Š5.6, the VAS score decreased from 6.9 ±â€Š2.3 to 1.8 ±â€Š1.5, and the SF36 score increased from 48.7 ±â€Š9.4 to 83.5 ±â€Š6.2. TAS increased from 83.3 ±â€Š5.1 to 90.3 ±â€Š6.1, TTS increased from 70.3 ±â€Š6.1 to 82.5 ±â€Š5.4, TT decreased from 12.9 ±â€Š6.1 to 6.9 ±â€Š5.7, and TLS increased from 76.5 ±â€Š4.1 to 81.2 ±â€Š3.3 (P < .05).Osteotomy combined with lateral ligament reconstruction is effective for the treatment of talar osteochondral lesion with varus ankle, which could relieve the arthritic symptoms induced by cartilage lesions. By correcting the force line on lower limbs and metapedes with osteotomy completely, the treatments on talar osteochondral lesion and lateral ligament reconstruction are the critical factors with better results.

Structural and biological investigation of chitosan/hyaluronic acid with silanized-hydroxypropyl methylcellulose as an injectable reinforced interpenetrating network hydrogel for cartilage tissue engineering.

Cartilage damage continues to pose a threat to humans, but no treatment is currently available to fully restore cartilage function. In this study, a new class of composite hydrogels derived from water-soluble chitosan (CS)/hyaluronic acid (HA) and silanized-hydroxypropyl methylcellulose (Si-HPMC) (CS/HA/Si-HPMC) has been synthesized and tested as injectable hydrogels for cartilage tissue engineering when combined without the addition of a chemical crosslinking agent. Mechanical studies of CS/HA and CS/HA/Si-HPMC hydrogels showed that as Si-HPMC content increased, swelling rate and rheological properties were higher, compressive strength decreased and degradation was faster. Our results demonstrate that the CS and HA-based hydrogel scaffolds, especially the ones with 3.0% (w/v) Si-HPMC and 2.5/4.0% (w/v) CS/HA, have suitable physical performance and bioactive properties, thus provide a potential opportunity to be used for cartilage tissue engineering. In vitro studies of CS/HA and CS/HA/Si-HPMC hydrogels encapsulated in chondrocytes have shown that the proper amount of Si-HPMC increases the proliferation and deposition of the cartilage extracellular matrix. The regeneration rate of the CS/HA/Si-HPMC (3%) hydrogel reached about 79.5% at 21 days for long retention periods, indicating relatively good in vivo bone regeneration. These CS/HA/Si-HPMC hydrogels are promising candidates for tissue compatibility injectable scaffolds. The data provide proof of the principle that the resulting hydrogel has an excellent ability to repair joint cartilage using a tissue-engineered approach.RESEARCH HIGHLIGHTSAn injectable hydrogel based on CS/HA/Si-HPMC composites was developed.The CS/HA/Si-HPMC hydrogel displays the tunable rheological with mechanical properties.The CS/HA/Si-HPMC hydrogel is highly porous with high swelling and degradation ratio.Increasing concentration of Si-HPMC promote an organized network in CS/HA/Si-HPMC hydrogels.Injectable CS/HA/Si-HPMC hydrogels have a high potential for cartilage tissue engineering.

Genome-wide analysis of hippocampal transfer RNA-derived small RNAs identifies new potential therapeutic targets of Bushen Tiansui formula against Alzheimer's disease.

OBJECTIVE: Bushen Tiansui formula (BSTSF), a traditional Chinese medicine prescription, has been widely used to treat Alzheimer's disease (AD). However, the mechanisms underlying its effects remain largely unknown. In this study, a rat AD model was used to study the effects of BSTSF on cognitive performance and expression of transfer RNA-derived small RNAs (tsRNAs) in the hippocampus, to determine whether treatment of AD with BSTSF could regulate the expression of tsRNAs, a novel small non-coding RNA. METHODS: To generate a validated AD model, oligomeric amyloid-ß1-42 (Aß1-42) was injected intracerebroventricularly into rats. The Morris water maze (MWM) test was used to evaluate rat cognitive performance, and tsRNA-sequencing was conducted to examine tsRNA expression in the rat hippocampus. Potential targets were validated by quantitative real-time polymerase chain reaction (qRT-PCR). Bioinformatic analyses were conducted to investigate the biological function of candidate tsRNAs. RESULTS: The learning and memory deficits of Aß1-42-induced AD rats, assessed by MWM tests, were clearly ameliorated by BSTSF treatment. A total of 387 tsRNAs were detected in the rat hippocampus. Among them, 13 were significantly dysregulated in AD rats compared with sham control rats, while 57 were markedly altered by BSTSF treatment, relative to untreated AD rats (fold change ≥ 2 and P < 0.05). Moreover, six BSTSF treatment-related tsRNAs were identified and validated by qRT-PCR. Bioinformatic analyses indicated that the six treatment-related tsRNAs had potential therapeutic roles, via multiple signaling pathways and Gene Ontology biological functions, including cyclic adenosine monophosphate and retrograde endocannabinoid signaling. CONCLUSION: This study identified a previously uncharacterized mechanism underlying the effects of BSTSF in alleviating the learning and memory deficits in Aß1-42-induced AD rats, demonstrating that tsRNAs are potential therapeutic targets of BSTSF in the treatment of AD.

Cytotoxic benzopyranone and xanthone derivatives from a coral symbiotic fungus Cladosporium halotolerans GXIMD 02502.

Coral-derived microorganisms have been historically proven to be prolific sources of bioactive secondary metabolites. Twelve benzopyranone and/or xanthone derivatives, including a new benzopyranone with an uncommon carboxyl group at C-8, coniochaetone K (1), were obtained from the Beibu Gulf-derived coral symbiotic fungus Cladosporium halotolerans GXIMD 02502. Their structures were determined by extensive spectroscopic data interpretation and comparison with literature values. The absolute configuration of 1 was accomplished by comparison of specific optical rotation as well as quantum chemical ECD calculations. The in vitro cytotoxicity of compounds 1-12 against two human prostatic cancer cell lines, C4-2B and 22RV1, were evaluated. And compounds 1, 3, 6-8, and 10-11 demonstrated significant cytotoxicity with inhibitions ranging from 55.8% to 82.1% at the concentration of 10 µM.

Rewiring of glycerol metabolism in Escherichia coli for effective production of recombinant proteins.

BACKGROUND: The economic viability of a protein-production process relies highly on the production titer and the price of raw materials. Crude glycerol coming from the production of biodiesel is a renewable and cost-effective resource. However, glycerol is inefficiently utilized by Escherichia coli. RESULTS: This issue was addressed by rewiring glycerol metabolism for redistribution of the metabolic flux. Key steps in central metabolism involving the glycerol dissimilation pathway, the pentose phosphate pathway, and the tricarboxylic acid cycle were pinpointed and manipulated to provide precursor metabolites and energy. As a result, the engineered E. coli strain displayed a 9- and 30-fold increase in utilization of crude glycerol and production of the target protein, respectively. CONCLUSIONS: The result indicates that the present method of metabolic engineering is useful and straightforward for efficient adjustment of the flux distribution in glycerol metabolism. The practical application of this methodology in biorefinery and the related field would be acknowledged.

A Strategy to Improve Production of Recombinant Proteins in Escherichia coli Based on a Glucose-Glycerol Mixture and Glutamate.

Enzymes have a wide range of applications in many sectors of the industry, and the market value has skyrocketed in recent years. Glucose and glycerol are two renewable carbon sources of importance. Therefore, it is appealing to produce recombinant enzymes with these carbon substrates on the basis of economic viability. In this study, glycerol metabolism and glucose metabolism in Escherichia coli (E. coli) were manipulated in a systematic way. In addition, glutamate (Glu) was used for replacement of yeast extract to reduce the cost and the quality-variation problem. A strategy was further developed to incorporate Glu into the central metabolism. The engineered E. coli strain finally enabled efficient co-utilization of glucose and glycerol and improved biomass and protein production by 4.3 and 8.2-folds, respectively. The result illustrates that this proposed approach is promising for effective production of recombinant proteins.