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1.
ACS Chem Biol ; 19(7): 1440-1446, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38901034

RESUMO

Peptide-bile acid hybrids offer promising drug candidates due to enhanced pharmacological properties, such as improved protease resistance and oral bioavailability. However, it remains unknown whether bile acids can be incorporated into peptide chains by the ribosome to produce a peptide-bile acid hybrid macrocyclic peptide library for target-based de novo screening. In this study, we achieved the ribosomal incorporation of lithocholic acid (LCA)-d-tyrosine into peptide chains. This led to the construction of a peptide-LCA hybrid macrocyclic peptide library, which enabled the identification of peptides TP-2C-4L3 (targeting Trop2) and EP-2C-4L5 (targeting EphA2) with strong binding affinities. Notably, LCA was found to directly participate in binding to EphA2 and confer on the peptides improved stability and resistance to proteases. Cell staining experiments confirmed the high specificity of the peptides for targeting Trop2 and EphA2. This study highlights the benefits of LCA in peptides and paves the way for de novo discovery of stable peptide-LCA hybrid drugs.


Assuntos
Ácido Litocólico , Biblioteca de Peptídeos , Peptídeos , Ribossomos , Ácido Litocólico/química , Ácido Litocólico/análogos & derivados , Ácido Litocólico/metabolismo , Ribossomos/metabolismo , Humanos , Peptídeos/química , Peptídeos/metabolismo , Receptor EphA2/metabolismo , Receptor EphA2/química , Descoberta de Drogas , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo
2.
J Transl Med ; 22(1): 561, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867256

RESUMO

BACKGROUND: Fibrogenesis within ovarian endometrioma (endometrioma), mainly induced by transforming growth factor-ß (TGF-ß), is characterized by myofibroblast over-activation and excessive extracellular matrix (ECM) deposition, contributing to endometrioma-associated symptoms such as infertility by impairing ovarian reserve and oocyte quality. However, the precise molecular mechanisms that underpin the endometrioma- associated fibrosis progression induced by TGF-ß remain poorly understood. METHODS: The expression level of lysine acetyltransferase 14 (KAT14) was validated in endometrium biopsies from patients with endometrioma and healthy controls, and the transcription level of KAT14 was further confirmed by analyzing a published single-cell transcriptome (scRNA-seq) dataset of endometriosis. We used overexpression, knockout, and knockdown approaches in immortalized human endometrial stromal cells (HESCs) or human primary ectopic endometrial stromal cells (EcESCs) to determine the role of KAT14 in TGF-ß-induced fibrosis. Furthermore, an adeno-associated virus (AAV) carrying KAT14-shRNA was used in an endometriosis mice model to assess the role of KAT14 in vivo. RESULTS: KAT14 was upregulated in ectopic lesions from endometrioma patients and predominantly expressed in activated fibroblasts. In vitro studies showed that KAT14 overexpression significantly promoted a TGF-ß-induced profibrotic response in endometrial stromal cells, while KAT14 silencing showed adverse effects that could be rescued by KAT14 re-enhancement. In vivo, Kat14 knockdown ameliorated fibrosis in the ectopic lesions of the endometriosis mouse model. Mechanistically, we showed that KAT14 directly interacted with serum response factor (SRF) to promote the expression of α-smooth muscle actin (α-SMA) by increasing histone H4 acetylation at promoter regions; this is necessary for TGF-ß-induced ECM production and myofibroblast differentiation. In addition, the knockdown or pharmacological inhibition of SRF significantly attenuated KAT14-mediating profibrotic effects under TGF-ß treatment. Notably, the KAT14/SRF complex was abundant in endometrioma samples and positively correlated with α-SMA expression, further supporting the key role of KAT14/SRF complex in the progression of endometrioma-associated fibrogenesis. CONCLUSION: Our results shed light on KAT14 as a key effector of TGF-ß-induced ECM production and myofibroblast differentiation in EcESCs by promoting histone H4 acetylation via co-operating with SRF, representing a potential therapeutic target for endometrioma-associated fibrosis.


Assuntos
Endometriose , Fibrose , Fator de Resposta Sérica , Fator de Crescimento Transformador beta , Adulto , Animais , Feminino , Humanos , Camundongos , Endometriose/patologia , Endometriose/metabolismo , Endométrio/metabolismo , Endométrio/patologia , Histona Acetiltransferases/metabolismo , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Fator de Resposta Sérica/metabolismo , Células Estromais/metabolismo , Células Estromais/patologia , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
3.
Protein Expr Purif ; 218: 106447, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38369031

RESUMO

Diaminopropionate ammonia-lyase transforms D and L isomers of 2,3-diaminopropionate to pyruvate and ammonia. It catalyzes D- and l-serine less effectively. L-2,3-diaminopropionate is a precursor in the biosynthesis of oxalyl diaminopropionate as a neurotoxin in certain legume species. In this work, we cyclized the diaminopropionate ammonia-lyase from Salmonella typhimurium in vitro using the redox-responsive split intein, and identified that backbone cyclization afforded the enzyme with the improved activity, thermal stability and resistance to the exopeptidase proteolysis, different from effects of the incorporated sequence recognized by tobacco vein mottling virus protease at C-terminus. Using analyses of three fluorescent dyes including 8-anilino-1-naphthalenesulfonic acid, N-phenyl-1-naphthylamine, and thioflavin T, the same amounts of the cyclic protein displayed less fluorescence than those of the linear protein upon the heat treatment. The cyclic enzyme displayed the enhanced activity in Escherichia coli cells using the designed novel reporter. In this system, d-serine was added to the culture and transported into the cytoplasm. It was transformed by pre-overexpression of the diaminopropionate ammonia-lyase, and untransformed d-serine was oxidized by the coproduced human d-amino acid oxidase to generate hydrogen peroxide. This oxidant is monitored by the HyPer indicator. The current results presented that the cyclized enzyme could be applied as a better candidate to block the neurotoxin biosynthesis in certain plant species.


Assuntos
Amônia-Liases , Neurotoxinas , Salmonella typhimurium , Humanos , Ciclização , Escherichia coli/genética , Serina
4.
J Am Chem Soc ; 145(51): 28264-28275, 2023 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-38092662

RESUMO

Conserved cysteine frameworks are essential components of disulfide-rich peptides (DRPs), which dominantly define the structural diversity of both naturally occurring and de novo-designed DRPs. However, there are only very limited numbers of conserved cysteine frameworks, and general methods enabling de novo discovery of cysteine frameworks with robust foldability are still not available. Here, we devised a "touchstone"-based strategy that relies on chasing oxidative foldability between two individual disulfide-rich folds on the phage surface to discover new cysteine frameworks from random sequences. Unique cysteine frameworks with a high degree of compatibility with phage display systems and broad sequence tolerance were successfully identified, which were subsequently exploited for the development of multicyclic DRP libraries, enabling the rapid discovery of new peptide ligands with low-nanomolar and picomolar binding affinity. This study provides an unprecedented method for exploring and exploiting the sequence and structure space of DRPs that is not readily accessible by existing strategies, holding the potential to revolutionize the study of DRPs and significantly advance the design and discovery of multicyclic peptide ligands and drugs.


Assuntos
Cisteína , Biblioteca de Peptídeos , Cisteína/química , Ligantes , Peptídeos/química , Dissulfetos/química
5.
Cytotherapy ; 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38054912

RESUMO

Allogeneic hemopoietic cell transplantation remains the goal of therapy for high-risk acute myeloid leukemia (AML). However, treatment failure in the form of leukemia relapse or severe graft-versus-host disease remains a critical area of unmet need. Recently, significant progress has been made in the cell therapy-based interventions both before and after transplant. In this review, the Stem Cell Engineering Committee of the International Society for Cell and Gene Therapy summarizes the literature regarding the identification of high risk in AML, treatment approaches before transplant, optimal transplant platforms and measures that may be taken after transplant to ideally prevent, or, if need be, treat AML relapse. Although some strategies remain in the early phases of clinical investigation, they are built on progress in pre-clinical research and cellular engineering techniques that are already improving outcomes for children and adults with high-risk malignancies.

6.
Cancer Cell Int ; 23(1): 319, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087309

RESUMO

BACKGROUND: CD56 has been observed in malignant tumours exhibiting neuronal or neuroendocrine differentiation, such as breast cancer, small-cell lung cancer, and neuroblastoma. Abnormal glycosylation modifications are thought to play a role in regulating tumour cell proliferation, migration, and invasion. Nevertheless, the exact roles and molecular mechanisms of CD56 and polysialylated CD56 (PSA-CD56) in the development and progression of clear cell renal cell carcinoma (ccRCC) remain elusive. Here we unveil the biological significance of CD56 and PSA-CD56 in ccRCC. METHODS: In this study, we employed various techniques, including immunohistochemistry (IHC), RT-qPCR, and western blot, to examine the mRNA and protein expression levels in both human ccRCC tissue and cell lines. Lentivirus infection and CRISPR/Cas9 system were utilized to generate overexpression and knockout cell lines of CD56. Additionally, we conducted several functional assays, such as CCK-8, colony formation, cell scratch, and transwell assays to evaluate cell growth, proliferation, migration, and invasion. Furthermore, we established a xenograft tumor model to investigate the role of CD56 in ccRCC in vivo. To gain further insights into the molecular mechanisms associated with CD56, we employed the Hedgehog inhibitor JK184 and the ß-catenin inhibitor Prodigiosin. RESULTS: CD56 was significantly overexpressed in both human ccRCC tissues and renal cancer cell lines compared to adjacent normal tissues and normal renal epithelial cells. In vitro and in vivo experiments revealed that the knockout of CD56 inhibited the proliferation, migration, and invasion capabilities of ccRCC cells, whereas the overexpression of PSA-CD56 promoted these capacities. Finally, PSA-CD56 overexpression was found to activate both the Hedgehog and Wnt/ß-catenin signaling pathways. CONCLUSION: Our findings demonstrate that the oncogenic function of CD56 polysialylation plays a vital role in the tumorigenesis and progression of ccRCC, implying that targeting PSA-CD56 might be a feasible treatment target for ccRCC.

7.
Aging (Albany NY) ; 15(6): 2082-2096, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36920166

RESUMO

BACKGROUND: Uveal melanoma is a highly malignant tumor in the eye. Its recurrence and metastasis are common, and the prognosis is poor. METHODS: The transcriptome data of UVM were downloaded from TCGA database, and the single cell sequencing dataset GSE139829 was downloaded from GEO database. Weighted co-expression network analysis was used to explore the modules associated with m7G. Lasso regression was used to construct M7G-related prognostic signature. Immune infiltration analysis was used to explore the significance of the model in the tumor immune microenvironment. Finally, cell assays were used to explore the function of key genes in the MUM-2B and OCM-1 cell lines of UVM. RESULTS: The prognostic signature was constructed by Cox regression and Lasso regression. Patients could be divided into high-risk group and low-risk group by this signature, and the high-risk group had worse prognosis (P<0.05). Cell experiments showed that the proliferation, invasion and migration ability of UVM cell lines were significantly decreased after the knockdown of PAG1, a key gene in signature, which proved that PAG1 might be a potential target of UVM. CONCLUSIONS: Our study explored the significance of m7G in UVM, provided biomarkers for its diagnosis and treatment.


Assuntos
Melanoma , Neoplasias Uveais , Humanos , Prognóstico , Melanoma/genética , Neoplasias Uveais/genética , Microambiente Tumoral/genética , Proteínas de Membrana , Proteínas Adaptadoras de Transdução de Sinal
8.
J Am Chem Soc ; 145(3): 1964-1972, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36633218

RESUMO

Multicyclic peptides with stable 3D structures are a kind of novel and promising peptide formats for drug design and discovery as they have the potential to combine the best characteristics of small molecules and proteins. However, the development of multicyclic peptides is largely limited to naturally occurring products. It remains a big challenge to develop multicyclic peptides with new structures and functions without recourse to the existing natural scaffolds. Here, we report a general and robust method relying on the utility of new disulfide-directing motifs for designing and discovering diverse multicyclic peptides with potent protein-binding capability. These peptides, referred to as disulfide-directed multicyclic peptides (DDMPs), are tolerant to extensive sequence manipulations and variations of disulfide-pairing frameworks, enabling the development of de novo DDMP libraries useful for ligand and drug discovery. This study opens a new avenue for creating a new generation of multicyclic peptides in sequence and structure space inaccessible by natural scaffolds, thus would greatly benefit the field of peptide drug discovery.


Assuntos
Dissulfetos , Biblioteca de Peptídeos , Ligantes , Peptídeos/química , Desenho de Fármacos
9.
Ann Transl Med ; 10(15): 839, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36034986

RESUMO

Background and Objective: Transient receptor potential (TRP) channels are a superfamily of functionally diverse and widely expressed cation channels which exhibit complex regulatory patterns and sensitivity to multiple environmental factors. The involvement of these ion channels is critical in various physiological functions and pathophysiological conditions. In recent decades, a growing number of studies have identified the essential role that TRP channels play in many ocular diseases. In this study, we performed a narrative review of research on the expression and function of TRP channels in various eye diseases. Methods: PubMed, Google Scholar, and Web of Science were searched for all relevant original papers and reviews published from database inception to January 31, 2022. Searches were conducted using the related keywords 'transient receptor potential channels', 'TRPs', 'Ca2+ signaling', 'iron channel', 'TRPV4', 'TRPM1', 'retina', 'optic nerve', 'cornea', 'retinal ganglion cells', 'ON-bipolar', 'TRPs and retina', 'TRP channel and retinal ganglion cells', 'TRPs and cornea', 'diabetes', 'glaucoma', 'dry eye disease', 'cataract', 'retinopathy of prematurity', 'retinoblastoma', and 'congenital stationary night blindness'. Key Content and Findings: In this narrative review, we summarize the history of TRP channels and introduce the TRP channel-related literature in eye disease. Next, we discuss the molecular mechanisms of TRP channels in various eye diseases and suggest future research directions. Conclusions: The relevant studies indicate that TRP channels play vital roles in various eye diseases. However, considerable work is needed to more fully understand the functional and mechanistic aspects of how TRP channels contribute to the pathophysiology of eye disease, especially in the context of animal models and patients. Further investigations will aid in the development of future drugs targeting TRP channels for eye diseases.

10.
Plant Physiol Biochem ; 186: 31-39, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35803089

RESUMO

Exploring novel growth regulators for premature senescence regulation is important for tobacco production. In the present study, chlorine dioxide (ClO2) was explored as a novel plant growth regulator for tobacco growth, particularly its effect on leaf senescence and root development. The results showed that 0.15 µM ClO2 maintained the lushness of detached leaves and whole plants. Also, the leaves of ClO2-treated plants exhibited a chlorophyll content of 58% higher than in CK (control) plants (P < 0.05). Besides, ClO2 treatment increased the biomass of roots and aboveground parts by 54 and 16%, respectively. The ClO2-treated plants also showed enhanced activities of antioxidant enzymes and significantly reduced malondialdehyde contents (P < 0.05). Moreover, ClO2 treatment remarkably alleviated drought-caused premature senescence in the tobacco plants and partly rescued the exogenous ethylene-caused plant dwarfism. The indole-3-acetic acid content in ClO2-treated plants was higher than in non-treated plants (P < 0.05), but ethylene content was significantly lower (P < 0.05). Gene expression analysis showed that ClO2 treatment remarkably suppressed ethylene synthase genes. However, the auxin biosynthesis and transport genes were up-regulated, with NtIAA17 increasing by five folds (P < 0.05). Further, ClO2 remarkably up-regulated the expression of chlorophyll biosynthesis genes, with a >20-fold increase in NtHEMA1 and NtCHLH expressions. These results designate ClO2 as a potential regulator for improving tobacco productivity by retaining higher chlorophyll content and promoting root growth.


Assuntos
Nicotiana , Senescência Vegetal , Compostos Clorados , Clorofila/metabolismo , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Óxidos , Folhas de Planta/metabolismo , Nicotiana/metabolismo
11.
Chem Sci ; 13(26): 7780-7789, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35865895

RESUMO

Peptides constrained through multiple disulfides (or disulfide-rich peptides, DRPs) have been an emerging frontier for ligand and drug discovery. Such peptides have the potential to combine the binding capability of biologics with the stability and bioavailability of smaller molecules. However, DRPs with stable three-dimensional (3D) structures are usually of natural origin or engineered from natural ones. Here, we report the discovery and identification of CPPC (cysteine-proline-proline-cysteine) motif-directed DRPs with stable 3D structures (i.e., CPPC-DRPs). A range of new CPPC-DRPs were designed or selected from either random or structure-convergent peptide libraries. Thus, for the first time we revealed that the CPPC-DRPs can maintain diverse 3D structures by taking advantage of constraints from unique dimeric CPPC mini-loops, including irregular structures and regular α-helix and ß-sheet folds. New CPPC-DRPs that can specifically bind the receptors (CD28) on the cell surface were also successfully discovered and identified using our DRP-discovery platform. Overall, this study provides the basis for accessing an unconventional peptide structure space previously inaccessible by natural DRPs and computational designs, inspiring the development of new peptide ligands and therapeutics.

12.
Front Cardiovasc Med ; 9: 821267, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463783

RESUMO

Background: In our clinical work, we found that cancer patients were susceptible to coronary atherosclerotic heart disease (CAD). However, less is known about the relationship between CAD and cancer. The present study aimed to identify the risk factors for CAD and cancer, as well as the relationship between CAD and cancer. Methods: In this retrospective study, 1600 patients between January 2012 and June 2019 were enrolled and divided into groups according to whether they had CAD or cancer. Single-factor and multivariate analysis methods were applied to examine the risk factors for CAD and cancer. Results: (1) Cancer prevalence was significantly higher in patients with CAD than in patients without CAD (47.2 vs. 20.9%). The prevalence of CAD in cancer and non-cancer patients was 78.9 and 52.4%, respectively. (2) Multivariable logistic regression showed that patients with cancer had a higher risk of developing CAD than non-cancer patients (OR: 2.024, 95% CI: 1.475 to 2.778, p < 0.001). Respiratory (OR: 1.981, 95% CI: 1.236-3.175, p = 0.005), digestive (OR: 1.899, 95% CI: 1.177-3.064, p = 0.009) and urogenital (OR: 3.595, 95% CI: 1.696-7.620, p = 0.001) cancers were significantly associated with a higher risk of CAD compared with no cancer. (3) Patients with CAD also had a higher risk of developing cancer than non-CAD patients (OR = 2.157, 95% CI: 1.603 to 2.902, p < 0.001). Patients in the Alanine aminotransferase (ALT) level ≥ 40 U/L group had a lower risk of cancer than patients in the ALT level < 20 U/L group (OR: 0.490, 95% CI: 0.333-0.722, p < 0.001). (4) An integrated variable (Y = 0.205 × 10-1 age - 0.595 × 10-2 HGB - 0.116 × 10-1 ALT + 0.135 FIB) was identified for monitoring the occurrence of cancer among CAD patients, with an AUC of 0.720 and clinical sensitivity/specificity of 0.617/0.711. Conclusion: (1) We discovered that CAD was an independent risk factor for cancer and vice versa. (2) Digestive, respiratory and urogenital cancers were independent risk factors for CAD. (3) We created a formula for the prediction of cancer among CAD patients. (4) ALT, usually considered a risk factor, was proven to be a protective factor for cancer in this study.

13.
J Am Chem Soc ; 144(11): 5116-5125, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35289603

RESUMO

The engineering of naturally occurring disulfide-rich peptides (DRPs) has been significantly hampered by the difficulty of manipulating disulfide pairing. New DRPs that take advantage of fold-directing motifs and noncanonical thiol-bearing amino acids are easy-to-fold with expected disulfide connectivities, representing a new class of scaffolds for the development of peptide ligands and therapeutics. However, the limited diversity of the scaffolds and particularly the use of noncanonical amino acids [e.g., penicillamine (Pen)] that are difficult to be translated by ribosomes greatly hamper the further development and application of these DRPs. Here, we designed and synthesized noncanonical bisthiol motifs bearing sterically obstructed thiol groups analogous to the Pen thiol to direct the folding of peptides into specific bicyclic and tricyclic structures. These bisthiol motifs can be ribosomally incorporated into peptides through a commercially available PURE system integrated with genetic code reprograming, which enables, for the first time, the in vitro expression of bicyclic peptides with two noncanonical and orthogonal disulfide bonds. We further constructed a bicyclic peptide library encoded by mRNA, with which new bicyclic peptide ligands with nanomolar affinity to proteins were successfully selected. Therefore, this study provides a new, general, and robust method for discovering de novo DRPs with new structures and functions not derived from natural peptides, which would greatly benefit the field of peptide drug discovery.


Assuntos
Dissulfetos , Biblioteca de Peptídeos , Aminoácidos , Dissulfetos/química , Ligantes , Peptídeos/química , Ribossomos , Compostos de Sulfidrila
14.
Ann Med ; 54(1): 1047-1057, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36799362

RESUMO

Introduction: Bispecific antibody (BiAb)-armed activated T cells (BATs) comprise an adoptive T cell therapy platform for treating cancer. Arming activated T cells (ATC) with anti-CD3 x anti-tumour associated antigen (TAA) BiAbs converts ATC into non-major histocompatibility complex (MHC)-restricted anti-tumour cytotoxic T lymphocytes (CTLs). Binding of target antigens via the BiAb bridge enables specific anti-tumour cytotoxicity, Th1 cytokines release, and T cell proliferation. Clinical trials in breast, prostate, and pancreatic cancer using BATs armed with chemically heteroconjugated BiAbs demonstrated safety, feasibility, induction of anti-tumour immune responses and potential increases in overall survival (OS).Objectives: The primary objective of this study was to develop a recombinant BiAb that confers enhanced anti-tumour activity of BATs against a broad range of solid tumours.Methods: A recombinant anti-epidermal growth factor receptor (EGFR) x anti-CD3 (OKT3) BiAb (rEGFRBi) was designed and expressed in CHO cells, used to arm ATC (rEGFR-BATs), and tested for specific cytotoxicity against breast, pancreatic and prostate cancers and glioblastoma.Results: rEGFR-BATs exhibit remarkably enhanced specific cytotoxicity and T1 cytokine secretion against a wide range of solid tumour cell lines vs. their respective chemically-heteroconjugated BATs.Conclusion: rEGFR-BATs may provide a "universal" T cell therapy for treating a wide range of solid tumours. KEY MESSAGEA (Gly4Ser)6 linker between the variable light and heavy chains of an scFv fused to the N-terminus of a heavy chain antibody confers unexpected stability to the heavy chain fusion protein and supports the efficient expression of the bispecific antibody.Arming of activated T cells with the rEGFRBi greatly enhances the relative cytotoxicity and Th1 cytokine secretion of theT cells relative to a chemically heteroconjugated BiAbs.rEGFR-BATs are promising candidates for the treatment of a broad range of solid tumours.


Assuntos
Anticorpos Biespecíficos , Neoplasias , Animais , Cricetinae , Humanos , Masculino , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Biespecíficos/farmacologia , Cricetulus , Citocinas , Linfócitos T/metabolismo , Neoplasias/imunologia , Neoplasias/terapia
15.
Chem Sci ; 12(34): 11464-11472, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34567500

RESUMO

Natural disulfide-rich peptides (DRPs) are valuable scaffolds for the development of new bioactive molecules and therapeutics. However, there are only a limited number of topologically distinct DRP folds in nature, and most of them suffer from the problem of in vitro oxidative folding. Thus, strategies to design DRPs with new constrained topologies beyond the scope of natural folds are desired. Herein we report a general evolution-inspired strategy to design new DRPs with diverse disulfide frameworks, which relies on the incorporation of two cysteine residues and a random peptide sequence into a precursor disulfide-stabilized fold. These peptides can spontaneously fold in redox buffers to the expected tricyclic topologies with high yields. Moreover, we demonstrated that these DRPs can be used as templates for the construction of phage-displayed peptide libraries, enabling the discovery of new DRP ligands from fully randomized sequences. This study thus paves the way for the development of new DRP ligands and therapeutics with structures not derived from natural DRPs.

16.
Ann Palliat Med ; 10(7): 8506-8511, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34263610

RESUMO

Pericardial tamponade is a complication of percutaneous coronary intervention (PCI) with extremely high mortality. The rupture of coronary artery causes hypotension and shock, eventually resulting in death due to pericardial tamponade. Because of the complex operation in revascularization of chronic total occlusion (CTO-PCI) lesion, the incidence of pericardial tamponade increases. Usually, we use coronary angiogram to identify the rupture of coronary artery after PCI by the contrast agent. We presented a 67-year-old woman with pericardial tamponade after CTO revascularization. She had chest pain and out of breath for nearly two years. The coronary angiogram showed three branch lesion and CTO lesion of the right coronary artery (RCA). After revascularization of the RCA CTO lesion, the pericardial effusion and low blood pressure occurred, but we didn't find the leak of contrast agents during the final angiography. Then the patient was transferred to cardiac surgery department for emergency thoracotomy. They found the hematoma on the surface of the RCA and finally discharged without any symptoms. Our case approved: (I) there was still the possibility of coronary artery rupture even the coronary angiogram showed no contrast agent leakage from the coronary artery after PCI; (II) the combined use of IVUS and coronary angiogram may improve the accuracy and safety of CTO revascularization procedure.


Assuntos
Tamponamento Cardíaco , Oclusão Coronária , Intervenção Coronária Percutânea , Idoso , Tamponamento Cardíaco/diagnóstico por imagem , Tamponamento Cardíaco/etiologia , Doença Crônica , Angiografia Coronária , Oclusão Coronária/diagnóstico por imagem , Feminino , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Resultado do Tratamento
17.
Mol Med Rep ; 24(1)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34080663

RESUMO

Sepsis­induced myocardial dysfunction is one of the features of multiple organ dysfunction in sepsis, which is associated with extremely high mortality and is characterized by impaired myocardial compliance. To date, there are few effective treatment options available to cure sepsis. Tannic acid (TA) is reportedly protective during sepsis; however, the underlying mechanisms by which TA protects against septic heart injury remain elusive. The present study investigated the potential effects and underlying mechanisms of TA in alleviating lipopolysaccharide (LPS)­induced H9C2 cardiomyocyte cell apoptosis. H9C2 cells were treated with LPS (15 µg/ml), TA (10 µM) and TA + LPS; control cells were treated with medium only. Apoptosis was measured using flow cytometry, reverse transcription­quantitative PCR (RT­qPCR) and western blot analysis. Additionally, the levels of cellular reactive oxygen species (ROS), malondialdehyde and nicotinamide adenine dinucleotide phosphate were evaluated. Western blotting and RT­qPCR were also employed to detect the expression levels of endoplasmic reticulum (ER) stress­associated functional proteins. The present findings demonstrated that TA reduced the degree of LPS­induced H9C2 cell injury, including inhibition of ROS production and ER stress (ERS)­associated apoptosis. ERS­associated functional proteins, including activating transcription factor 6, protein kinase­like ER kinase, inositol­requiring enzyme 1, spliced X box­binding protein 1 and C/EBP­homologous protein were suppressed in response to TA treatment. Furthermore, the expression levels of ERS­associated apoptotic proteins, including c­Jun N­terminal kinase, Bax, cytochrome c, caspase­3, caspase­12 and caspase­9 were reduced following treatment with TA. Additionally, the protective effects of TA on LPS­induced H9C2 cells were partially inhibited following treatment with the ROS inhibitor N­acetylcysteine, which demonstrated that ROS mediated ERS­associated apoptosis and TA was able to decrease ROS­mediated ERS­associated apoptosis. Collectively, the present findings demonstrated that the protective effects of TA against LPS­induced H9C2 cell apoptosis may be associated with the amelioration of ROS­mediated ERS. These findings may assist the development of potential novel therapeutic methods to inhibit the progression of myocardial cell injury.


Assuntos
Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Lipopolissacarídeos/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Taninos/farmacologia , Acetilcisteína/farmacologia , Animais , Linhagem Celular , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Ratos
18.
ACS Omega ; 5(49): 31525-31534, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33344804

RESUMO

Based on the targeting of ferroferric oxide (Fe3O4) and the drug-loading property of carbon nanotubes (CNTs), a novel Span-PEG-composited Fe3O4-CNTs-DOX multifunctional ultrasound contrast agent was designed and applied to tumor lesions. In situ liquid phase synthesis was employed to prepare the Fe3O4-CNTs magnetic targeting complex, and the physical method was used to obtain the Fe3O4-CNTs-DOX complex by loading doxorubicin (DOX) onto Fe3O4-CNTs. The targeted drug-loading complex Fe3O4-CNTs-DOX was combined with the membrane material of Span-PEG by the acoustic vibration cavitation method. The maximum tolerance for Span-PEG-composited Fe3O4-CNTs-DOX microbubbles was 450 times higher, which has good safety. The loading rate of DOX in the obtained composite microbubbles was 17.02%. The proliferation inhibition rate of Span-PEG-composited Fe3O4-CNTs-DOX microbubbles on liver cancer SMMC-7721 cells reached 48.3%. Span-PEG-composited Fe3O4-CNTs-DOX microbubbles could significantly enhance ultrasonic imaging and enrich at a specific location under an external magnetic field, and the extended imaging time could ensure the effective observation and diagnosis of lesions.

19.
J Am Chem Soc ; 142(38): 16285-16291, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32914969

RESUMO

Disulfide-rich peptides (DRPs) have been an emerging frontier for drug discovery. There have been two DRPs approved as drugs (i.e., Ziconotide and Linaclotide), and many others are undergoing preclinical studies or in clinical trials. All of these DRPs are of nature origin or derived from natural peptides. It is still a challenge to design new DRPs without recourse to natural scaffolds due to the difficulty in handling the disulfide pairing. Here we developed a simple and robust strategy for directing the disulfide pairing and folding of peptides with up to six cysteine residues. Our strategy exploits the dimeric pairing of CPPC (cysteine-proline-proline-cysteine) motifs for directing disulfide formation, and DRPs with different multicyclic topologies were designed and synthesized by regulating the patterns of CPPC motifs and cysteine residues in peptides. As neither sequence manipulations nor unnatural amino acids are involved, the designed DRPs can be used as templates for the de novo development of biosynthetic multicyclic peptide libraries, enabling selection of DRPs with new functions directly from fully randomized sequences. We believe that this work represents as an important step toward the discovery and design of new multicyclic peptide ligands and therapeutics with structures not derived from natural scaffolds.


Assuntos
Dissulfetos/química , Biblioteca de Peptídeos , Peptídeos/química , Conformação Proteica , Dobramento de Proteína
20.
Health Aff (Millwood) ; 38(5): 835-843, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31059368

RESUMO

To understand the future trajectory of health expenditure in China if current trends continue and the estimated impact of reforms, this study projected health expenditure by disease and function from 2015 to 2035. Current health expenditure in China is projected to grow 8.4 percent annually, on average, in that period. The growth will mainly be driven by rapid increases in services per case of disease and unit cost, which respectively contribute 4.3 and 2.4 percentage points. Circulatory disease expenditure is projected to increase to 23.4 percent of health expenditure by 2035. The biggest challenge facing the Chinese health system is the projected rapid growth in inpatient services. Three percent of gross domestic product could be saved by 2035 by slowing the growth of inpatient service use from 8.2 percent per year in 2016 to 3.5 percent per year in 2035. Health expenditure in 2035 could be reduced by 3.5 percent if the smoking rate were cut in half and by 3.4 percent if the high blood pressure rate were cut by 25 percent. Future action in controlling health expenditure growth in China should focus on the high growth in inpatient services expenditure and interventions to reduce risk factors.


Assuntos
Reforma dos Serviços de Saúde , Gastos em Saúde/tendências , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China , Política de Saúde , Humanos , Lactente , Pessoa de Meia-Idade , Adulto Jovem
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