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1.
Microb Cell Fact ; 23(1): 196, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987741

RESUMO

BACKGROUND: Telomerase activators are promising agents for the healthy aging process and the treatment/prevention of short telomere-related and age-related diseases. The discovery of new telomerase activators and later optimizing their activities through chemical and biological transformations are crucial for the pharmaceutical sector. In our previous studies, several potent telomerase activators were discovered via fungal biotransformation, which in turn necessitated optimization of their production. It is practical to improve the production processes by implementing the design of experiment (DoE) strategy, leading to increased yield and productivity. In this study, we focused on optimizing biotransformation conditions utilizing Camarosporium laburnicola, a recently discovered filamentous fungus, to afford the target telomerase activators (E-CG-01, E-AG-01, and E-AG-02). RESULTS: DoE approaches were used to optimize the microbial biotransformation processes of C. laburnicola. Nine parameters were screened by Plackett-Burman Design, and three significant parameters (biotransformation time, temperature, shaking speed) were optimized using Central Composite Design. After conducting validation experiments, we were able to further enhance the production yield of target metabolites through scale-up studies in shake flasks (55.3-fold for E-AG-01, 13-fold for E-AG-02, and 1.96-fold for E-CG-01). CONCLUSION: Following a process optimization study using C. laburnicola, a significant increase was achieved in the production yields. Thus, the present study demonstrates a promising methodology to increase the production yield of potent telomerase activators. Furthermore, C. laburnicola is identified as a potential biocatalyst for further industrial utilization.


Assuntos
Biotransformação , Telomerase , Telomerase/metabolismo , Ativadores de Enzimas/metabolismo
2.
Microb Cell Fact ; 22(1): 66, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024895

RESUMO

BACKGROUND: Cycloartane-type triterpenoids possess important biological activities, including immunostimulant, wound healing, and telomerase activation. Biotransformation is one of the derivatization strategies of natural products to improve their bioactivities. Endophytic fungi have attracted attention in biotransformation studies because of their ability to perform modifications in complex structures with a high degree of stereospecificity. RESULTS: This study focuses on biotransformation studies on cyclocephagenol (1), a novel cycloartane-type sapogenin from Astragalus species, and its 12-hydroxy derivatives (2 and 3) to obtain new telomerase activators. Since the hTERT protein levels of cyclocephagenol (1) and its 12-hydroxy derivatives (2 and 3) on HEKn cells were found to be notable, biotransformation studies were carried out on cyclocephagenol and its 12-hydroxy derivatives using Camarosporium laburnicola, an endophytic fungus isolated from Astragalus angustifolius. Later, immunoblotting and PCR-based ELISA assay were used to screen starting compounds and biotransformation products for their effects on hTERT protein levels and telomerase activation. All compounds showed improved telomerase activation compared to the control group. CONCLUSIONS: As a result of biotransformation studies, seven new metabolites were obtained and characterized, verifying the potential of C. laburnicola as a biocatalyst. Additionally, the bioactivity results showed that this endophytic biocatalyst is unique in transforming the metabolites of its host to afford potent telomerase activators.


Assuntos
Ascomicetos , Sapogeninas , Telomerase , Sapogeninas/metabolismo , Telomerase/metabolismo , Ascomicetos/metabolismo , Biotransformação
3.
Stem Cells ; 41(3): 233-241, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36330760

RESUMO

Telomerase, consisting of the protein subunit telomerase reverse transcriptase (TERT) and RNA component TERC, is best known for maintaining and extending human telomeres, the ends of linear chromosomes, in tissues, where it is active, such as stem cells, germline cells, lymphocytes and endothelial cells. This function is considered as canonical. However, various non-canonical functions for the protein part TERT have been discovered. There are multiple such roles which can interfere with several signaling pathways, cancer development and many other processes. One of these non-canonical functions includes shuttling of the TERT protein out of the nucleus upon increased oxidative stress into the cytoplasm and organelles such as mitochondria. Mitochondrial TERT is able to protect cells from oxidative stress, DNA damage and apoptosis although the exact mechanisms are incompletely understood. Recently, a protective role for TERT was described in brain neurons. Here TERT is able to counteract effects of toxic neurodegenerative proteins via changes in gene expression, activation of neurotrophic factors as well as activation of protein degrading pathways such as autophagy. Protein degradation processes are prominently involved in degrading toxic proteins in the brain like amyloid-ß, pathological tau and α-synuclein that are responsible for various neurodegenerative diseases. These new findings can have implications for the development of novel treatment strategies for neurodegenerative diseases. The current review summarizes our knowledge on the role of the telomerase protein TERT in brain function, in particular, under the aspect of age-related neurodegenerative diseases. It also describes various strategies to increase TERT levels in the brain.


Assuntos
Doenças Neurodegenerativas , Telomerase , Humanos , Doenças Neurodegenerativas/genética , Telomerase/metabolismo , Células Endoteliais/metabolismo , Encéfalo/metabolismo , Estresse Oxidativo , Telômero/metabolismo
4.
J Colloid Interface Sci ; 608(Pt 2): 1222-1228, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34735856

RESUMO

Cycloastragenol (CA) is a plant saponin that functions as a telomerase activator, and it has been made as an oral anti-aging supplement and use as active ingredient in topical cosmetic products. The anti-aging performance in cosmetic products have only been evaluated by description of skin appearance, while direct topical penetration of CA across the skin barrier still needs to be confirmed. The objective of this work was to design encapsulation vehicles to deliver CA across the skin barrier using commercially available ingredients through scalable processes, and to prove its topical penetration. Phospholipid vesicles including liposomes, ethosomes, and transethosomes were prepared using soy and sunflower phospholipids and different penetration enhancers, including ethanol and surfactants. The loading capacity of CA was analyzed using high performance liquid chromatography, and the topical penetration of CA was evaluated using Franz diffusion cells with pig skin. Transethosomes using Tween 80, Span 40, or dicetylphosphate as the penetration enhancer showed better CA delivery across the skin barrier than ethosomes or emulsifier α-gels. Results of this work provide evidence that CA encapsulated in phospholipid vesicles can be transported across the skin barrier. These encapsulation systems could be used for the design of CA-containing anti-aging cosmetic products.


Assuntos
Fosfolipídeos , Absorção Cutânea , Administração Cutânea , Animais , Portadores de Fármacos , Sapogeninas , Suínos
5.
Mol Biol Res Commun ; 10(1): 1-4, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33681391

RESUMO

Spirulina platensis is a photosynthetic filamentous, edible cyanobacterium that is known as a superfood. In this study, sapogenins were extracted from the spirulina and the effects of these compounds on telomerase activity were evaluated in MCF7 and HDF cell lines using Telomeric Repeat Amplification Protocol and ELIZA assay. The highest increase in telomerase activity was observed at 0.004 mg/ml of sapogenin by 26% ±20.5 in MCF7 cells, while in HDF cells in the same concentration telomerase activity decreased down to 47%±0.48 and the highest inhibition of telomerase activity was observed at 0.070 mg/ml of sapogenins from Spirulina by 68%±0.43. In conclusion, a compound could play a role as a telomerase activator in one cell line while it could play another role as a telomerase inhibitor in another cell line so introducing compounds as a telomerase inhibitor (anticancer) or as a telomerase activator (anti-aging) should be done with discreet.

6.
Prog Neurobiol ; 199: 101953, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33188884

RESUMO

Protective effects of the telomerase protein TERT have been shown in neurons and brain. We previously demonstrated that TERT protein can accumulate in mitochondria of Alzheimer's disease (AD) brains and protect from pathological tau in primary mouse neurons. This prompted us to employ telomerase activators in order to boost telomerase expression in a mouse model of Parkinson's disease (PD) overexpressing human wild type α-synuclein. Our aim was to test whether increased Tert expression levels were able to ameliorate PD symptoms and to activate protein degradation. We found increased Tert expression in brain for both activators which correlated with a substantial improvement of motor functions such as gait and motor coordination while telomere length in the analysed region was not changed. Interestingly, only one activator (TA-65) resulted in a decrease of reactive oxygen species from brain mitochondria. Importantly, we demonstrate that total, phosphorylated and aggregated α-synuclein were significantly decreased in the hippocampus and neocortex of activator-treated mice corresponding to enhanced markers of autophagy suggesting an improved degradation of toxic alpha-synuclein. We conclude that increased Tert expression caused by telomerase activators is associated with decreased α-synuclein protein levels either by activating autophagy or by preventing or delaying impairment of degradation mechanisms during disease progression. This encouraging preclinical data could be translated into novel therapeutic options for neurodegenerative disorders such as PD.


Assuntos
Doença de Parkinson , alfa-Sinucleína/metabolismo , Animais , Autofagia , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Doença de Parkinson/genética , Telomerase/genética , alfa-Sinucleína/genética
7.
JMIR Res Protoc ; 9(9): e19456, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32965237

RESUMO

BACKGROUND: Inflammation plays a key role in the pathophysiology of coronary heart disease (CHD) and its acute manifestation, acute coronary syndrome (ACS). Aging is associated with a decline of the immune system, a process known as immunosenescence. This is characterized by an increase in highly proinflammatory T cells that are involved in CHD progression, plaque destabilization, and myocardial ischemia-reperfusion injury. Telomere dysfunction has been implicated in immunosenescence of T lymphocytes. Telomerase is the enzyme responsible for maintaining telomeres during cell divisions. It has a protective effect on cells under oxidative stress and helps regulate flow-mediated dilation in microvasculature. OBJECTIVE: The TACTIC (Telomerase ACTivator to reverse Immunosenescence in Acute Coronary Syndrome) trial will investigate whether a telomerase activator, TA-65MD, can reduce the proportion of senescent T cells in patients with ACS with confirmed CHD. It will also assess the effect of TA-65MD on decreasing telomere shortening, reducing oxidative stress, and improving endothelial function. METHODS: The study was designed as a single-center, randomized, double-blind, parallel-group, placebo-controlled phase II trial. Recruitment started in January 2019. A total of 90 patients, aged 65 years or older, with treated ACS who have had CHD confirmed by angiography will be enrolled. They will be randomized to one of two groups: TA-65MD oral therapy (8 mg twice daily) or placebo taken for 12 months. The primary outcome is the effect on immunosenescence determined by a decrease in the proportion of CD8+ TEMRA (T effector memory cells re-expressing CD45RA [CD45 expressing exon A]) cells at 12 months. Secondary outcomes include leukocyte telomere length, endothelial function, cardiac function as measured by echocardiography and NT-proBNP (N-terminal fragment of the prohormone brain-type natriuretic peptide), systemic inflammation, oxidative stress, and telomerase activity. RESULTS: The study received National Health Service (NHS) ethics approval on August 9, 2018; Medicines and Healthcare products Regulatory Agency approval on October 19, 2018; and NHS Health Research Authority approval on October 22, 2018. The trial began recruiting participants in January 2019 and completed recruitment in March 2020; the trial is due to report results in 2021. CONCLUSIONS: This pilot trial in older patients with CHD will explore outcomes not previously investigated outside in vitro or preclinical models. The robust design ensures that bias has been minimized. Should the results indicate reduced frequency of immunosenescent CD8+ T cells as well as improvements in telomere length and endothelial function, we will plan a larger, multicenter trial in patients to determine if TA-65MD is beneficial in the treatment of CHD in elderly patients. TRIAL REGISTRATION: ISRCTN Registry ISRCTN16613292; http://www.isrctn.com/ISRCTN16613292 and European Union Drug Regulating Authorities Clinical Trials Database (EudraCT), European Union Clinical Trials Register 2017-002876-26; https://tinyurl.com/y4m2so8g. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/19456.

8.
Exp Ther Med ; 16(3): 2175-2182, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30186456

RESUMO

Cycloastragenol (CAG) is a triterpenoid saponin compound and a hydrolysis product of the main active ingredient in Astragalus membranaceus (Fisch.) Bunge. An increasing body of evidence has indicated that CAG has a wide spectrum of pharmacological functions, which are attracting attention in the research community. The aim of the present review paper was to review and elucidate the advanced study of CAG. The focus was on advanced studies of CAG in English and Chinese databases; the literature was collected and reviewed to summarize the latest efficacy, pharmacokinetics and adverse reactions of CAG. Extensive pharmacological effects have been attributed to CAG, including telomerase activation, telomere elongation, anti-inflammatory and anti-oxidative properties; CAG has also been reported to improve lipid metabolism. Clinical research has demonstrated that CAG activates telomerase in humans and ameliorates various biomarkers. CAG is absorbed through the intestinal epithelium via passive diffusion and undergoes first-pass hepatic metabolism. Within a certain dose range, oral CAG is relatively safe; however, underlying mechanisms associated with CAG are not clear, and thus, we should be aware of potential adverse reactions associated with CAG. According to existing studies and clinical trials, CAG is safe and has broad application prospects. However, further studies are required to fully understand its efficacy and potential adverse reactions, and to ensure the proper use of CAG is applied to treat diseases clinically.

9.
Curr Pharm Des ; 24(17): 1905-1911, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29546832

RESUMO

BACKGROUND: Telomerase Activator 65 (TA-65), a compound extracted from Astragalus membranaceus has been used in Chinese traditional medicine for extending lifespan. Scarce information exists on the effects of TA-65 on parameters of metabolic syndrome (MetS). METHODS: We recruited 40 patients with MetS to determine the effects of TA-65 on dyslipidemias, hypertension, and oxidative stress in this at-risk population. The study was a double-blind, randomized crossover design in which patients were allocated to consume either 16 mg daily of a TA-65 supplement or a placebo for 12 weeks. Following a 3-week washout, participants were allocated to the alternate treatment for an additional 12 weeks. Anthropometric and biological markers were measured at the end of each treatment. Plasma lipids, glucose, CReactive Protein (CRP), liver enzymes, and glycosylated hemoglobin were measured using a Cobas c-111. Inflammatory cytokines were measured by Luminex technology and markers of oxidative stress by the use of spectroscopy. RESULTS: Compared to the placebo period, HDL cholesterol (HDL-C) was higher while body mass index, waist circumference, and the LDL/HDL ratio were lower (p < 0.05) during TA-65 treatment. In addition, plasma tumor necrosis factor-α (TNF-α) was lower during the TA-65 period (p < 0.05). Positive correlations were observed in changes between the placebo and the TA-65 periods in HDL-C and CRP (r = -0.511, p < 0.01), alanine aminotransferase (r = -0.61, p < 0.001) and TNF-α (r = -0.550, p < 0.001) suggesting that the favorable changes observed in HDL were associated with decreases in inflammation. CONCLUSION: TA-65 improved key markers of cardiovascular disease risk, which were also associated with reductions in inflammation.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Ativadores de Enzimas/uso terapêutico , Síndrome Metabólica/tratamento farmacológico , Telomerase/metabolismo , Adulto , Idoso , Antioxidantes/metabolismo , Astragalus propinquus/química , Biomarcadores/metabolismo , Doenças Cardiovasculares/metabolismo , Método Duplo-Cego , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Dislipidemias/tratamento farmacológico , Dislipidemias/metabolismo , Ativadores de Enzimas/química , Ativadores de Enzimas/farmacologia , Feminino , Glucose/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Medicina Tradicional Chinesa , Síndrome Metabólica/metabolismo , Pessoa de Meia-Idade , Raízes de Plantas/química
10.
Bioorg Med Chem Lett ; 24(22): 5242-6, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25305686

RESUMO

The length of telomeres controls the life span of eukaryotic cells. Telomerase maintains the length of telomeres in certain eukaryotic cells, such as germline cells and stem cells, and allows these cells to evade replicative senescence. Here, we report for the first time a number of curcuminoid derivatives that enhance telomerase activity in an in vitro TRAP assay. A preliminary analysis of structure-activity relationships found that the minimal requirement for this enhanced telomerase activity is a curcuminoid core with at least one n-pentylpyridine side chain, while curcuminoids with two such side chains exhibit even greater activity. The finding here might lead to a new class of telomerase activators that act directly or indirectly on telomerase, rather than through the reactivation of the telomerase reverse transcriptase (TERT) gene associated with other telomerase activators found in the literature.


Assuntos
Curcumina/química , Curcumina/farmacologia , Telomerase/metabolismo , Astragalus propinquus/enzimologia , Curcumina/metabolismo , Ativação Enzimática/efeitos dos fármacos , Técnicas de Amplificação de Ácido Nucleico , Oligonucleotídeos/química , Oligonucleotídeos/metabolismo , Relação Estrutura-Atividade , Telomerase/química
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