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1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(3): 491-496, 2023 May.
Artigo em Chinês | MEDLINE | ID: mdl-37248573

RESUMO

Tumor microenvironment incorporates various tumor-related cellular and non-cellular components, playing a crucial role in the process of the pathogenesis, growth, and metastasis of tumors. Long noncoding RNA (lncRNA), a kind of noncoding RNA with a length of more than 200 nt, participates in a variety of physiological and pathological processes. Recent studies have shown that lncRNA plays a vital role in the interaction between tumors and the tumor microenvironment, thereby affecting tumor progression. Herein, we reviewed the research progress on the lncRNA in tumor microenvironment, discussed the potential application of lncRNA in early diagnosis and treatment of tumors, and suggested that some issues should be further explored in future research, including developing effective strategies for knocking out specific lncRNA and selecting appropriate in vivo delivery vehicles targeting specific cells.


Assuntos
Neoplasias , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Microambiente Tumoral/genética , Neoplasias/genética , Regulação Neoplásica da Expressão Gênica
2.
Proc Natl Acad Sci U S A ; 116(39): 19635-19645, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31488714

RESUMO

Substance P (SP) regulates multiple biological processes through its high-affinity neurokinin-1 receptor (NK-1R). While the SP/NK-1R signaling axis is involved in the pathogenesis of solid cancer, the role of this signaling pathway in hematological malignancy remains unknown. Here, we demonstrate that NK-1R expression is markedly elevated in the white blood cells from acute myeloid leukemia patients and a panel of human leukemia cell lines. Blocking NK-1R induces apoptosis in vitro and in vivo via increase of mitochondrial reactive oxygen species. This oxidative stress was triggered by rapid calcium flux from the endoplasmic reticulum into mitochondria and, consequently, impairment of mitochondrial function, a mechanism underlying the cytotoxicity of NK-1R antagonists. Besides anticancer activity, blocking NK-1R produces a potent antinociceptive effect in myeloid leukemia-induced bone pain by alleviating inflammation and inducing apoptosis. These findings thus raise the exciting possibility that the NK-1R antagonists, drugs currently used in the clinic for preventing chemotherapy-induced nausea and vomiting, may provide a therapeutic option for treating human myeloid leukemia.


Assuntos
Leucemia Mieloide Aguda/terapia , Mitocôndrias/efeitos dos fármacos , Receptores da Neurocinina-1/metabolismo , Substância P/farmacologia , Adulto , Idoso , Animais , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Inflamação/metabolismo , Leucemia/terapia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Antagonistas dos Receptores de Neurocinina-1/farmacologia , Estresse Oxidativo , Transdução de Sinais/efeitos dos fármacos , Substância P/metabolismo
3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(5): 885-892, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31631640

RESUMO

Mouse animal models are the most commonly used experimental tools in scientific research, which have been widely favored by researchers. The animal model of mouse leukemia appeared in the 1930s. During the past 90 years, researchers have developed various types of mouse leukemia models to simulate the development and treatment of human leukemia in order to promote effectively the elucidation of the molecular mechanism of leukemia' development and progression, as well as the development of targeted drugs for the treatment of leukemia. Considering that to myeloid leukemia, especially acute myeloid leukemia, there currently is no good clinical treatment, it is urgent to clarify its new molecular mechanism and develop new therapeutic targets. This review focuses on the various types of mouse models about myeloid leukemia used commonly in recent years, including mouse strains, myeloid leukemia cell types, and modeling methods, which are expected to provide a reference for relevant researchers to select animal models during myeloid leukemia research.


Assuntos
Modelos Animais de Doenças , Leucemia Mieloide Aguda , Animais , Humanos , Camundongos
4.
Angew Chem Int Ed Engl ; 58(5): 1392-1396, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30474173

RESUMO

Protein therapeutics are increasingly used to treat various diseases, yet they often suffer from short serum half-lives. An emerging strategy to extend lifetime in vivo is to attach fatty acids onto proteins to increase their binding to human serum albumin (HSA). Herein, the genetic encoding of ϵ-N-heptanoyl-l-lysine (HepoK) is reported, which introduces a fatty-acid-containing amino acid into proteins with exquisite site-specificity and homogeneity, overcoming issues associated with existing chemical conjugation methods. The expression in E .coli and purification of HepoK-incorporated glucagon-like peptide-1 (GLP1) is demonstrated. GLP1(HepoK) showed stronger binding to HSA than GLP1(WT), without impairing the stimulation of the GLP1 receptor in cells. Moreover, GLP1(HepoK) decreased blood glucose level to the same level as GLP1(WT) in mice, showing longer-lasting effects than GLP1(WT). HepoK incorporation will also be useful for investigating the function of protein lipidation.


Assuntos
Aminoácidos/genética , Código Genético/genética , Peptídeo 1 Semelhante ao Glucagon/genética , Lipídeos/genética , Lisina/genética , Animais , Escherichia coli/genética , Peptídeo 1 Semelhante ao Glucagon/isolamento & purificação , Meia-Vida , Lisina/análogos & derivados , Camundongos , Camundongos Endogâmicos ICR
5.
J Am Chem Soc ; 140(35): 11058-11066, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-30132658

RESUMO

Acidic vesicles and organelles play fundamental roles in a broad range of cellular events such as endocytosis, lysosomal degradation, synaptic transmission, pathogen fate, and drug delivery. Fluorescent reporters will be invaluable for studying these complex and multifunctional systems with spatiotemporal resolution, yet common fluorescent proteins are generally nonfluorescent at acidic conditions due to the decrease of anionic chromophores upon protonation, but are fluorescent at physiological pH, creating interfering fluorescence from nonvesicle regions. Here we developed a novel acid-brightening fluorescent protein (abFP) that fluoresces strongly at acidic pH but is nonfluorescent at or above neutral pH, boasting a pH profile opposite to that of common fluorescent proteins. Through expansion of the genetic code, we incorporated a quinoline-containing amino acid Qui into the chromophore of EGFP to reverse the chromophore charge. Protonation of Qui rendered a cationic chromophore, which resulted in unique fluorescence increase only at acidic pH in vitro, in E. coli cells, and on the mammalian cell surface. We further demonstrated that abFP-tagged δ opioid receptors were fluorescently imaged in lysosome showing distinct features and without background fluorescence from other cellular regions, whereas EGFP-tagged receptors were invisible in lysosome. This Qui-rendered cationic chromophore strategy may be generally applied to other fluorescent proteins to generate a palette of colors for acidic imaging with minimal background, and these abFPs should facilitate the study of molecules in association with various acidic vesicles and organelles in different cells and model organisms.


Assuntos
Proteínas Luminescentes/química , Quinolinas/química , Aminoácidos/química , Aminoácidos/genética , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Fluorescência , Código Genético , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Proteínas Luminescentes/genética , Modelos Moleculares , Estrutura Molecular , Organelas/química , Organelas/genética
6.
J Am Chem Soc ; 140(15): 4995-4999, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29601199

RESUMO

Introducing new chemical reactivity into proteins in living cells would endow innovative covalent bonding ability to proteins for research and engineering in vivo. Latent bioreactive unnatural amino acids (Uaas) can be incorporated into proteins to react with target natural amino acid residues via proximity-enabled reactivity. To expand the diversity of proteins amenable to such reactivity in vivo, a chemical functionality that is biocompatible and able to react with multiple natural residues under physiological conditions is highly desirable. Here we report the genetic encoding of fluorosulfate-l-tyrosine (FSY), the first latent bioreactive Uaa that undergoes sulfur-fluoride exchange (SuFEx) on proteins in vivo. FSY was found nontoxic to Escherichia coli and mammalian cells; after being incorporated into proteins, it selectively reacted with proximal lysine, histidine, and tyrosine via SuFEx, generating covalent intraprotein bridge and interprotein cross-link of interacting proteins directly in living cells. The proximity-activatable reactivity, multitargeting ability, and excellent biocompatibility of FSY will be invaluable for covalent manipulation of proteins in vivo. Moreover, genetically encoded FSY hereby empowers general proteins with the next generation of click chemistry, SuFEx, which will afford broad utilities in chemical biology, drug discovery, and biotherapeutics.


Assuntos
Proteínas de Escherichia coli/química , Histidina/química , Lisina/química , Ácidos Sulfúricos/química , Tirosina/química , Fluoretos/química , Código Genético , Células HEK293 , Células HeLa , Humanos , Modelos Moleculares , Enxofre/química , Tirosina/análogos & derivados , Tirosina/genética
7.
Angew Chem Int Ed Engl ; 54(40): 11760-4, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26259671

RESUMO

Blockade of the protein-protein interaction between the transmembrane protein programmed cell death protein 1 (PD-1) and its ligand PD-L1 has emerged as a promising immunotherapy for treating cancers. Using the technology of mirror-image phage display, we developed the first hydrolysis-resistant D-peptide antagonists to target the PD-1/PD-L1 pathway. The optimized compound (D) PPA-1 could bind PD-L1 at an affinity of 0.51 µM in vitro. A blockade assay at the cellular level and tumor-bearing mice experiments indicated that (D) PPA-1 could also effectively disrupt the PD-1/PD-L1 interaction in vivo. Thus D-peptide antagonists may provide novel low-molecular-weight drug candidates for cancer immunotherapy.

8.
BMC Infect Dis ; 14: 523, 2014 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-25267108

RESUMO

BACKGROUND: Clostridium difficile carriage has been considered as a potential source for the deadly infection, but its role in cancer patients is still unclear. We aimed to identify the clinical and immunological factors that are related to C. difficile carriage in Chinese cancer patients. METHODS: A total of 400 stool samples were collected from cancer patients who received chemotherapy in three hospitals of eastern China. Bacterial genomic DNA was extracted and two toxin genes (tcdA and tcdB) were detected. PCR ribotyping was performed using capillary gel electrophoresis. Concentrations of prostaglandin E2 (PGE2), transforming growth factor beta (TGF-ß) and interleukin-10 (IL-10) were measured using enzyme-linked immunosorbent assay (ELISA) kits. RESULTS: Eighty-two (20.5%) samples were confirmed to be C. difficile-positive and positive for tpi, tcdA, and tcdB genes. The C. difficile-positive rates in patients with diarrhea and no diarrhea were 35% and 19.7%, respectively (p = 0.09). Patients who were younger than 50 years old and were hospitalized for at least 10 days had a C. difficile-positive rate as high as 35%. In contrast, patients who were older than 50 years old and were hospitalized for less than 10 days had a C. difficile-positive rate of only 12.7% (p = 0.0009). No association was found between C. difficile carriage and chemotherapy regimen, antibiotic drug use, or immunosuppressive mediators, such as prostaglandin E2 (PGE2), transforming growth factor beta (TGF-ß), or interleukin-10 (IL-10). Twelve ribotypes of C. difficile were identified, but none of them belonged to ribotype 027. CONCLUSIONS: We conclude that younger patients and those with longer hospitalization stays may be more prone to C. difficile carriage. Studies of larger populations are warranted to clarify the exact role of C. difficile carriage in hospitalized cancer patients in China.


Assuntos
Portador Sadio/epidemiologia , Clostridioides difficile/genética , Diarreia/epidemiologia , Enterocolite Pseudomembranosa/epidemiologia , Neoplasias/epidemiologia , Toxinas Bacterianas/genética , Portador Sadio/diagnóstico , Portador Sadio/microbiologia , China , DNA Bacteriano/genética , Diarreia/diagnóstico , Diarreia/microbiologia , Enterocolite Pseudomembranosa/diagnóstico , Enterocolite Pseudomembranosa/microbiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Hospitalização , Humanos , Interleucina-10/genética , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Neoplasias/microbiologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Ribotipagem
9.
J Zhejiang Univ Sci B ; 25(2): 91-105, 2024 Feb 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38303494

RESUMO

Recently, the substance P (SP)/neurokinin-1 receptor (NK-1R) system has been found to be involved in various human pathophysiological disorders including the symptoms of coronavirus disease 2019 (COVID-19). Besides, studies in the oncological field have demonstrated an intricate correlation between the upregulation of NK-1R and the activation of SP/NK-1R system with the progression of multiple carcinoma types and poor clinical prognosis. These findings indicate that the modulation of SP/NK-1R system with NK-1R antagonists can be a potential broad-spectrum antitumor strategy. This review updates the latest potential and applications of NK-1R antagonists in the treatment of human diseases and cancers, as well as the underlying mechanisms. Furthermore, the strategies to improve the bioavailability and efficacy of NK-1R antagonist drugs are summarized, such as solid dispersion systems, nanonization, and nanoencapsulation. As a radiopharmaceutical therapeutic, the NK-1R antagonist aprepitant was originally developed as radioligand receptor to target NK-1R-overexpressing tumors. However, combining NK-1R antagonists with other drugs can produce a synergistic effect, thereby enhancing the therapeutic effect, alleviating the symptoms, and improving patients quality of life in several diseases and cancers.


Assuntos
Neoplasias , Antagonistas dos Receptores de Neurocinina-1 , Humanos , Antagonistas dos Receptores de Neurocinina-1/farmacologia , Antagonistas dos Receptores de Neurocinina-1/uso terapêutico , Qualidade de Vida , Substância P , Receptores da Neurocinina-1 , Neoplasias/tratamento farmacológico
10.
J Zhejiang Univ Sci B ; 25(4): 341-353, 2024 Apr 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38584095

RESUMO

Kidney fibrosis is an inevitable result of various chronic kidney diseases (CKDs) and significantly contributes to end-stage renal failure. Currently, there is no specific treatment available for renal fibrosis. ELA13 (amino acid sequence: RRCMPLHSRVPFP) is a conserved region of ELABELA in all vertebrates; however, its biological activity has been very little studied. In the present study, we evaluated the therapeutic effect of ELA13 on transforming growth factor-ß1 (TGF-ß1)-treated NRK-52E cells and unilateral ureteral occlusion (UUO) mice. Our results demonstrated that ELA13 could improve renal function by reducing creatinine and urea nitrogen content in serum, and reduce the expression of fibrosis biomarkers confirmed by Masson staining, immunohistochemistry, real-time polymerase chain reaction (RT-PCR), and western blot. Inflammation biomarkers were increased after UUO and decreased by administration of ELA13. Furthermore, we found that the levels of essential molecules in the mothers against decapentaplegic (Smad) and extracellular signal-regulated kinase (ERK) pathways were reduced by ELA13 treatment in vivo and in vitro. In conclusion, ELA13 protected against kidney fibrosis through inhibiting the Smad and ERK signaling pathways and could thus be a promising candidate for anti-renal fibrosis treatment.


Assuntos
Nefropatias , Obstrução Ureteral , Camundongos , Animais , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Nefropatias/tratamento farmacológico , Nefropatias/metabolismo , Nefropatias/patologia , Transdução de Sinais , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/metabolismo , Fator de Crescimento Transformador beta1 , Rim/metabolismo , Fibrose , Biomarcadores/metabolismo
11.
Adv Healthc Mater ; : e2401005, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38663447

RESUMO

In chronic wound management, efficacious handling of exudate and bacterial infections stands as a paramount challenge. Here a novel biomimetic fabric, inspired by the natural transpiration mechanisms in plants, is introduced. Uniquely, the fabric combines a commercial polyethylene terephthalate (PET) fabric with asymmetrically grown 1D rutile titanium dioxide (TiO2) micro/nanostructures, emulating critical plant features: hierarchically porous networks and hydrophilic water conduction channels. This structure endows the fabric with exceptional antigravity wicking-evaporation performance, evidenced by a 780% one-way transport capability and a 0.75 g h-1 water evaporation rate, which significantly surpasses that of conventional moisture-wicking textiles. Moreover, the incorporated 1D rutile TiO2 micro/nanostructures present solar-light induced antibacterial activity, crucial for disrupting and eradicating wound biofilms. The biomimetic transpiration fabric is employed to drain exudate and eradicate biofilms in Staphylococcus aureus (S. aureus)-infected wounds, demonstrating a much faster infection eradication capability compared to clinically common ciprofloxacin irrigation. These findings illuminate the path for developing high-performance, textile-based wound dressings, offering efficient clinical platforms to combat biofilms associated with chronic wounds.

12.
J Pept Sci ; 19(9): 566-74, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23873700

RESUMO

Anoplin is a recently discovered antimicrobial peptide (AMP) isolated from the venom sac of the spider wasp Anoplius samariensis, and it is one of the shortest α-helical AMP found naturally to date consisting of only ten amino acids. Previous results showed that anoplin exhibits potent antimicrobial activity but little hemolytic activity. In this study, we synthesized anoplin, studied its cytotoxicity in Friend virus-induced leukemia cells [murine erythroleukemia (MEL) cells], and proposed its possible mechanism. Our results showed that anoplin could inhibit the proliferation of MEL cells in a dose-dependent and time-dependent manner via disrupting the integrity of cell membrane, which indicated that anoplin exerts its cytotoxicity efficacy. In addition, the cell cycle distribution of MEL cells was arrested in the G0/G1 phase significantly. However, anoplin could not induce obvious apoptosis in MEL cells, as well as anoplin could not induce visible changes on morphology and quantity in the bone marrow cells isolated from normal mice. All of these results indicate that anoplin, as generally believed, is a selective AMP, a value characteristic in the design of safe therapeutic agents. The cytotoxicity of anoplin on MEL cells was mainly attributable to the plasma membrane perturbation and also to the intracellular events such as the arrest of cell cycle. Although this is an initial study that explored the activity of anoplin in vitro rather than in vivo, with the increasing resistance of conventional chemotherapy, there is no doubt that anoplin has desirable feature to be developed as a novel and selective anticancer agent.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Antineoplásicos/farmacologia , Vírus da Leucemia Murina de Friend , Leucemia Eritroblástica Aguda/tratamento farmacológico , Venenos de Vespas/farmacologia , Animais , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Leucemia Eritroblástica Aguda/virologia , Camundongos
13.
Pharmaceuticals (Basel) ; 16(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36678567

RESUMO

Colon cancer is one of the most common digestive tract malignancies, having the second highest mortality rate among all tumors, with a five-year survival of advanced patients of only 10%. Efficient, targeted drugs are still lacking in treating colon cancer, so it is urgent to explore novel druggable targets. Here, we demonstrated that annexin A1 (ANXA1) was overexpressed in tumors of 50% of colon cancer patients, and ANXA1 overexpression was significantly negatively correlated with the poor prognosis of colon cancer. ANXA1 promoted the abnormal proliferation of colon cancer cells in vitro and in vivo by regulating the cell cycle, while the knockdown of ANXA1 almost totally inhibited the growth of colon cancer cells in vivo. Furthermore, ANXA1 antagonized the autophagic death of honokiol in colon cancer cells via stabilizing mitochondrial reactive oxygen species. Based on these results, we speculated that ANXA1 might be a druggable target to control colon cancer and overcome drug resistance.

14.
Int J Biol Macromol ; 242(Pt 3): 124907, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37230451

RESUMO

Reptiles can evolve adaptive colors in different environments, but relatively little is known about the genetic mechanisms. Here, we identified the MC1R gene and its association with intraspecific color variation in the lizard Phrynocephalus erythrurus. Analysis of the MC1R sequence in 143 individuals from dark South Qiangtang Plateau (SQP) and light North Qiangtang plateau (NQP) populations, revealed two amino acid sites that showed significant differences in frequency between two areas. One SNP, corresponding to Glu183Lys residue, was found to be a highly significant outlier and differentially fixed for SQP and NQP populations. This residue is located in an extracellular area in the second small extracellular loop within the secondary structure of MC1R, which represents an "attachment pocket" part of the 3D structure. Cytological expression of MC1R alleles with the Glu183Lys replacement showed a 39 % increase in intracellular agonist-induced cyclic AMP levels and a 23.18 % greater cell surface expression of MC1R protein in the SQP relative to the NQP allele. Further in silico 3D modeling and in vitro binding experiments indicated a higher MC1R-α-MSH binding for the SQP allele, and elevated melanin synthesis. We provide an overview of how a single amino acid replacement leads to fundamental changes in MC1R function, and hence shapes variation in dorsal pigmentation in lizards from different environments.


Assuntos
Lagartos , Animais , Humanos , Lagartos/genética , Aminoácidos/metabolismo , Tibet , Pigmentação/genética , Alelos
15.
Front Bioeng Biotechnol ; 10: 861924, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646859

RESUMO

Background: To compare the corneal biomechanics of thin normal cornea (TNC) with thinnest corneal thickness (TCT) (≤500 µm), forme-fruste keratoconus (FFKC) and cornea after small incision lenticule extraction (Post-SMILE) had their central corneal thickness (CCT) matched by Corneal Visualization Scheimpflug Technology (Corvis ST). Methods: CCT were matched in 23 eyes with FFKC, 23 eyes by SMILE in 3 months post-operatively, and 23 TNC eyes. The differences in corneal biomechanics by Corvis ST among the three groups were compared. Results: There was no significant difference in CCT among the three groups, and the biomechanically corrected intraocular pressure (bIOP) did not differ significantly among the three groups (all p > 0.05). There were significant differences in most DCR parameters between pre- and post-operatively (all p < 0.05). Compared with TNC, the values of corneal deflection amplitude during the first applanation (A1DA), length at the first applanation (A1L), corneal deflection amplitude during the second applanation (A2DA), and maximum deformation amplitude (DA) decreased in 3 months after SMILE (all p < 0.05), these values increased in the FFKC (all p < 0.05). Conclusion: The majority of the DCR parameters were different among the three groups. The parameters A1DA, A1L, A2DA, and DA may be different between TNC and Post-SMILE, TNC and FFKC, and Post-SMILE and FFKC.

16.
Genes Dis ; 9(6): 1493-1505, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36157506

RESUMO

Annexin A1, a well-known endogenous anti-inflammatory mediator, plays a critical role in a variety of pathological processes. Fibrosis is described by a failure of tissue regeneration and contributes to the development of many diseases. Accumulating evidence supports that Annexin A1 participates in the progression of tissue fibrosis. However, the fundamental mechanisms by which Annexin A1 regulates fibrosis remain elusive, and even the functions of Annexin A1 in fibrotic diseases are still paradoxical. This review focuses on the roles of Annexin A1 in the development of fibrosis of lung, liver, heart, and other tissues, with emphasis on the therapy potential of Annexin A1 in fibrosis, and presents future research interests and directions in fibrotic diseases.

17.
Signal Transduct Target Ther ; 7(1): 48, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35165272

RESUMO

Peptide drug development has made great progress in the last decade thanks to new production, modification, and analytic technologies. Peptides have been produced and modified using both chemical and biological methods, together with novel design and delivery strategies, which have helped to overcome the inherent drawbacks of peptides and have allowed the continued advancement of this field. A wide variety of natural and modified peptides have been obtained and studied, covering multiple therapeutic areas. This review summarizes the efforts and achievements in peptide drug discovery, production, and modification, and their current applications. We also discuss the value and challenges associated with future developments in therapeutic peptides.


Assuntos
Descoberta de Drogas , Peptídeos , Peptídeos/uso terapêutico
18.
Elife ; 112022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35758651

RESUMO

Hyperactivation of oncogenic pathways downstream of RAS and PI3K/AKT in normal cells induces a senescence-like phenotype that acts as a tumor-suppressive mechanism that must be overcome during transformation. We previously demonstrated that AKT-induced senescence (AIS) is associated with profound transcriptional and metabolic changes. Here, we demonstrate that human fibroblasts undergoing AIS display upregulated cystathionine-ß-synthase (CBS) expression and enhanced uptake of exogenous cysteine, which lead to increased hydrogen sulfide (H2S) and glutathione (GSH) production, consequently protecting senescent cells from oxidative stress-induced cell death. CBS depletion allows AIS cells to escape senescence and re-enter the cell cycle, indicating the importance of CBS activity in maintaining AIS. Mechanistically, we show this restoration of proliferation is mediated through suppressing mitochondrial respiration and reactive oxygen species (ROS) production by reducing mitochondrial localized CBS while retaining antioxidant capacity of transsulfuration pathway. These findings implicate a potential tumor-suppressive role for CBS in cells with aberrant PI3K/AKT pathway activation. Consistent with this concept, in human gastric cancer cells with activated PI3K/AKT signaling, we demonstrate that CBS expression is suppressed due to promoter hypermethylation. CBS loss cooperates with activated PI3K/AKT signaling in promoting anchorage-independent growth of gastric epithelial cells, while CBS restoration suppresses the growth of gastric tumors in vivo. Taken together, we find that CBS is a novel regulator of AIS and a potential tumor suppressor in PI3K/AKT-driven gastric cancers, providing a new exploitable metabolic vulnerability in these cancers.


Assuntos
Sulfeto de Hidrogênio , Neoplasias Gástricas , Cistationina , Cistationina beta-Sintase/genética , Cistationina beta-Sintase/metabolismo , Glutationa/metabolismo , Glicogênio Sintase , Humanos , Sulfeto de Hidrogênio/metabolismo , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Neoplasias Gástricas/genética
19.
Front Bioeng Biotechnol ; 9: 771763, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869287

RESUMO

Purpose: The aim of this study was to provide a method to determine corneal nonlinear viscoelastic properties based on the output data of corneal visualization Scheimpflug technology (Corvis ST). Methods: The Corvis ST data from 18 eyes of 12 healthy humans were collected. Based on the air-puff pressure and the corneal displacement from the Corvis ST test of normal human eyes, the work done by the air-puff attaining the whole corneal displacement was obtained. By applying a visco-hyperelastic strain energy density function of the cornea, in which the first-order Prony relaxation function and the first-order Ogden strain energy were employed, the corneal strain energy during the Corvis ST test was calculated. Then the work done by the air-puff attaining the whole corneal displacement was completely regarded as the strain energy of the cornea. The identification of the nonlinear viscoelastic parameters was carried out by optimizing the sum of difference squares of the work and the strain energy using the genetic algorithm. Results: The visco-hyperelastic model gave a good fit to the data of corneal strain energy with time during the Corvis ST test (R 2 > 0.95). The determined Ogden model parameter µ ranged from 0.42 to 0.74 MPa, and α ranged from 32.76 to 55.63. The parameters A and τ in the first-order Prony function were 0.09-0.36 and 1.21-1.95 ms, respectively. Conclusion: It is feasible to determine the corneal nonlinear viscoelastic properties based on the corneal contour information and air-puff pressure of the Corvis ST test.

20.
Int J Ophthalmol ; 14(4): 523-528, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33875942

RESUMO

AIM: To compare the effect of myopia and astigmatism correction and postoperative change in higher-order aberration as results of receiving small-incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK). METHODS: A prospective and non-randomized controlled study was conducted. The subjects are divided into two groups according to different operations received: 229 eyes of 116 patients in the SMILE group and 168 eyes of 86 patients in the FS-LASIK group. All subjects were followed up for 3mo by monitoring their uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), spherical equivalent, higher-order aberrations, and the preoperative and postoperative complications. RESULTS: At 1wk, 1, and 3mo post-surgery, 224 eyes (97.8%), 227 eyes (99.1%) and 229 eyes (100%) had UCVA≥20/20 in the SMILE group, while 165 eyes (98.2%), 167 eyes (99.4%) and 167 eyes (99.4%) had UCVA≥20/20 in the FS-LASIK group, respectively (χ 2=0.146, 2.135, and 1.124; all P>0.05). BCVA reduction was not observed in both groups at 1 and 3mo of post-surgery (χ 2=0.734 and 1.898, P>0.05). There was no statistically significant difference in the spherical equivalent between the two groups at 1 and 3mo post-surgery, though the percentage of the spherical equivalent within ±0.50 D at 3mo post-surgery was 98% in the SMILE group, which was higher than that of the FS-LASIK group (92%, χ 2=1.872, P>0.05). The root mean square (RMS) values of total high-order aberration, coma, and spherical aberration of the two groups increased significantly in the early postoperative period and decreased after 3mo, but the values were still higher than the preoperative levels (P<0.05); there was no significant difference between the two groups in the RMS values of total higher-order aberrations and specific higher-order aberrations (P>0.05). The incidence of complications in the SMILE group was lower than that in the FS-LASIK group (χ 2=14.52, P<0.05). CONCLUSION: SMILE and FS-LASIK can effectively treat myopia, significantly improve visual acuity, and increase the total high-order aberration, spherical aberration, and coma. The incidence of complications after SMILE is relatively low.

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