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1.
Arch Toxicol ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38744709

RESUMO

Increasing evidence has revealed that cellular senescence drives NDs, including Alzheimer's disease (AD) and Parkinson's disease. Different senescent cell populations secrete senescence-associated secretory phenotypes (SASP), including matrix metalloproteinase-3, interleukin (IL)-1α, IL-6, and IL-8, which can harm adjacent microglia. Moreover, these cells possess high expression levels of senescence hallmarks (p16 and p21) and elevated senescence-associated ß-galactosidase activity in in vitro and in vivo ND models. These senescence phenotypes contribute to the deposition of ß-amyloid and tau-protein tangles. Selective clearance of senescent cells and SASP regulation by inhibiting p38/mitogen-activated protein kinase and nuclear factor kappa B signaling attenuate ß-amyloid load and prevent tau-protein tangle deposition, thereby improving cognitive performance in AD mouse models. In addition, telomere shortening, a cellular senescence biomarker, is associated with increased ND risks. Telomere dysfunction causes cellular senescence, stimulating IL-6, tumor necrosis factor-α, and IL-1ß secretions. The forced expression of telomerase activators prevents cellular senescence, yielding considerable neuroprotective effects. This review elucidates the mechanism of cellular senescence in ND pathogenesis, suggesting strategies to eliminate or restore senescent cells to a normal phenotype for treating such diseases.

2.
BMC Public Health ; 24(1): 1293, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741111

RESUMO

BACKGROUND: New effective treatments for dementia are lacking, and early prevention focusing on risk factors of dementia is important. Non-pharmacological intervention therapies aimed at these factors may provide a valuable tool for reducing the incidence of dementia. This study focused on the development of a mathematical model to predict the number of individuals with neurodegenerative diseases, specifically Alzheimer's disease, Parkinson's disease, vascular dementia, and amyotrophic lateral sclerosis. Scenarios for non-pharmacological intervention therapies based on risk factor reduction were also assessed. The estimated total costs and potential cost savings from societal were included. METHODS: Based on demographic and financial data from the EU, a mathematical model was developed to predict the prevalence and resulting care costs of neurodegenerative diseases in the population. Each disease (Alzheimer's disease, Parkinson's disease, vascular dementia, and amyotrophic lateral sclerosis) used parameters that included prevalence, incidence, and death risk ratio, and the simulation is related to the age of the cohort and the disease stage. RESULTS: A replicable simulation for predicting the prevalence and resulting cost of care for neurodegenerative diseases in the population exhibited an increase in treatment costs from 267 billion EUR in 2021 to 528 billion EUR by 2050 in the EU alone. Scenarios related to the reduction of the prevalence of dementia by up to 20% per decade led to total discounted treatment cost savings of up to 558 billion EUR. CONCLUSION: The model indicates the magnitude of the financial burden placed on EU healthcare systems due to the growth in the population prevalence of neurodegenerative diseases in the coming decades. Lifestyle interventions based on reducing the most common risk factors could serve as a prevention strategy to reduce the incidence of dementia with substantial cost-savings potential. These findings could support the implementation of public health approaches throughout life to ultimately prevent premature mortality and promote a healthier and more active lifestyle in older individuals.


Assuntos
Demência , Humanos , Demência/economia , Demência/epidemiologia , Demência/prevenção & controle , Fatores de Risco , Europa (Continente)/epidemiologia , Redução de Custos , Idoso , Custos de Cuidados de Saúde/estatística & dados numéricos , Modelos Teóricos , Masculino , Feminino , Prevalência , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade
3.
Environ Toxicol Pharmacol ; 108: 104447, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38636744

RESUMO

This review systematically compiles sports-related drugs, substances, and methodologies based on the most frequently detected findings from prohibited lists published annually by the World Anti-Doping Agency (WADA) between 2003 and 2021. Aligned with structure of the 2023 prohibited list, it covers all proscribed items and details the pharmacokinetics and pharmacodynamics of five representatives from each section. Notably, it explores significant metabolites and metabolic pathways associated with these substances. Adverse analytical findings are summarized in tables for clarity, and the prevalence is visually represented through charts. The review includes a concise historical overview of doping and WADA's role, examining modifications in the prohibited list for an understanding of evolving anti-doping measures.

4.
Arch Toxicol ; 98(5): 1323-1367, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38483584

RESUMO

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are well recognized for playing a dual role, since they can be either deleterious or beneficial to biological systems. An imbalance between ROS production and elimination is termed oxidative stress, a critical factor and common denominator of many chronic diseases such as cancer, cardiovascular diseases, metabolic diseases, neurological disorders (Alzheimer's and Parkinson's diseases), and other disorders. To counteract the harmful effects of ROS, organisms have evolved a complex, three-line antioxidant defense system. The first-line defense mechanism is the most efficient and involves antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). This line of defense plays an irreplaceable role in the dismutation of superoxide radicals (O2•-) and hydrogen peroxide (H2O2). The removal of superoxide radicals by SOD prevents the formation of the much more damaging peroxynitrite ONOO- (O2•- + NO• → ONOO-) and maintains the physiologically relevant level of nitric oxide (NO•), an important molecule in neurotransmission, inflammation, and vasodilation. The second-line antioxidant defense pathway involves exogenous diet-derived small-molecule antioxidants. The third-line antioxidant defense is ensured by the repair or removal of oxidized proteins and other biomolecules by a variety of enzyme systems. This review briefly discusses the endogenous (mitochondria, NADPH, xanthine oxidase (XO), Fenton reaction) and exogenous (e.g., smoking, radiation, drugs, pollution) sources of ROS (superoxide radical, hydrogen peroxide, hydroxyl radical, peroxyl radical, hypochlorous acid, peroxynitrite). Attention has been given to the first-line antioxidant defense system provided by SOD, CAT, and GPx. The chemical and molecular mechanisms of antioxidant enzymes, enzyme-related diseases (cancer, cardiovascular, lung, metabolic, and neurological diseases), and the role of enzymes (e.g., GPx4) in cellular processes such as ferroptosis are discussed. Potential therapeutic applications of enzyme mimics and recent progress in metal-based (copper, iron, cobalt, molybdenum, cerium) and nonmetal (carbon)-based nanomaterials with enzyme-like activities (nanozymes) are also discussed. Moreover, attention has been given to the mechanisms of action of low-molecular-weight antioxidants (vitamin C (ascorbate), vitamin E (alpha-tocopherol), carotenoids (e.g., ß-carotene, lycopene, lutein), flavonoids (e.g., quercetin, anthocyanins, epicatechin), and glutathione (GSH)), the activation of transcription factors such as Nrf2, and the protection against chronic diseases. Given that there is a discrepancy between preclinical and clinical studies, approaches that may result in greater pharmacological and clinical success of low-molecular-weight antioxidant therapies are also subject to discussion.


Assuntos
Antioxidantes , Neoplasias , Humanos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peróxido de Hidrogênio , Superóxidos , Ácido Peroxinitroso/farmacologia , Antocianinas/metabolismo , Antocianinas/farmacologia , Estresse Oxidativo , Óxido Nítrico , Superóxido Dismutase/metabolismo , Doença Crônica
5.
Biomed Pharmacother ; 167: 115600, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37783152

RESUMO

Frentizole is immunosuppressive drug with low acute toxicity and lifespan-prolonging effect. Recently, frentizole´s potential to disrupt toxic amyloid ß (Aß) - Aß-binding alcohol dehydrogenase (ABAD) interaction in mitochondria in Alzheimer´s brains has been revealed. Another broadly studied drug with anti-aging and immunosuppressive properties is an mTOR inhibitor - rapamycin. Since we do not yet precisely know what is behind the lifespan-prolonging effect of rapamycin and frentizole, whether it is the ability to inhibit the mTOR signaling pathway, reduction in mitochondrial toxicity, immunosuppressive effect, or a combination of all of them, we have decided within our previous work to dock the entire in-house library of almost 240 Aß-ABAD modulators into the FKBP-rapamycin-binding (FRB) domain of mTOR in order to interlink mTOR-centric and mitochondrial free radical-centric theories of aging and thus to increase the chances of success. Based on the results of the docking study, molecular dynamic simulation and MM-PBSA calculations, we have selected nine frentizole-like compounds (1 - 9). Subsequently, we have determined their real physical-chemical properties (logP, logD, pKa and solubility in water and buffer), cytotoxic/cytostatic, mTOR inhibitory, and in vitro anti-senescence (senolytic and senomorphic) effects. Finally, the three best candidates (4, 8, and 9) have been forwarded for in vivo safety studies to assess their acute toxicity and pharmacokinetic properties. Based on obtained results, only compound 4 demonstrated the best results within in vitro testing, the ability to cross the blood-brain barrier and the lowest acute toxicity (LD50 in male mice 559 mg/kg; LD50 in female mice 575 mg/kg).


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Feminino , Masculino , Camundongos , Animais , Peptídeos beta-Amiloides/metabolismo , Senoterapia , Imunossupressores , Sirolimo , Serina-Treonina Quinases TOR
6.
Front Immunol ; 14: 1202098, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529045

RESUMO

Background and objectives: Glioblastoma multiforme (GBM) is the most aggressive, malignant, and therapy-resistant tumor of the brain. Blockade therapy targeting the programmed cell death protein 1 (PD-1)/programmed death ligand (PD-L1) axis is currently under investigation for the clinical management of the GBM. This study has quantified the plasma levels of PD-L1 as a biomarker for the clinical management of GBM. Methods: A cohort (n = 128) of Pakistani adult glioblastoma patients together with age- and sex-matched healthy controls was used for quantification of pre-surgery levels of plasma PD-L1. PD-L1 protein and mRNA were measured by PD-L1 platinum enzyme-linked immunosorbent assay and quantitative real-time PCR, respectively. Receiver operating characteristic (ROC) curve analysis was used to compute area under the curve (AUC) for specificity and sensitivity analyses. The Kaplan-Meier survival analysis was employed to compute overall survival. Results: PD-L1 protein and mRNA were significantly higher in GBM compared to the healthy controls (p < 0.0001). Mean PD-L1 concentration for the GBM was found to be 48.98 ± 2.290 pg/ml compared to 27.63 ± 1.281 pg/ml for controls. Gene expression analysis showed statistically significant upregulation (p < 0.0001) of PD-L1 in blood of GBM compared to healthy controls. Plasma PD-L1 showed an AUC of 0.840 (p < 0.0001; 95% CI = 0.7716 to 0.9090) where a cutoff value higher than 46 pg/ml demonstrated 100% specificity and 57.81% sensitivity. Higher pre-surgery levels of PD-L1 were found to be associated with overall poor survival [p < 0.0001; HR (log-rank) = 0.08; 95% CI = 0.04 to 0.15]. Age, gender, and ethnic background were not found to be associated with plasma PD-L1 levels. Conclusion: The study concludes that blood-based measurements of PD-L1 in GBM can be a promising prognostic marker and therapeutic target besides a rapid and relatively non-invasive screening tool for routine clinical management. Future work extending the analysis to larger cohorts through multi-center collaborations involving pre-treatment and post-treatment groups is required to fully explore the usefulness of circulating PD-L1 for effective clinical applications.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Adulto , Humanos , Glioblastoma/diagnóstico , Glioblastoma/terapia , Glioblastoma/genética , Antígeno B7-H1/metabolismo , Estudos Retrospectivos , Ligantes , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/genética , Biomarcadores Tumorais/metabolismo
7.
Arch Toxicol ; 97(10): 2499-2574, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37597078

RESUMO

A physiological level of oxygen/nitrogen free radicals and non-radical reactive species (collectively known as ROS/RNS) is termed oxidative eustress or "good stress" and is characterized by low to mild levels of oxidants involved in the regulation of various biochemical transformations such as carboxylation, hydroxylation, peroxidation, or modulation of signal transduction pathways such as Nuclear factor-κB (NF-κB), Mitogen-activated protein kinase (MAPK) cascade, phosphoinositide-3-kinase, nuclear factor erythroid 2-related factor 2 (Nrf2) and other processes. Increased levels of ROS/RNS, generated from both endogenous (mitochondria, NADPH oxidases) and/or exogenous sources (radiation, certain drugs, foods, cigarette smoking, pollution) result in a harmful condition termed oxidative stress ("bad stress"). Although it is widely accepted, that many chronic diseases are multifactorial in origin, they share oxidative stress as a common denominator. Here we review the importance of oxidative stress and the mechanisms through which oxidative stress contributes to the pathological states of an organism. Attention is focused on the chemistry of ROS and RNS (e.g. superoxide radical, hydrogen peroxide, hydroxyl radicals, peroxyl radicals, nitric oxide, peroxynitrite), and their role in oxidative damage of DNA, proteins, and membrane lipids. Quantitative and qualitative assessment of oxidative stress biomarkers is also discussed. Oxidative stress contributes to the pathology of cancer, cardiovascular diseases, diabetes, neurological disorders (Alzheimer's and Parkinson's diseases, Down syndrome), psychiatric diseases (depression, schizophrenia, bipolar disorder), renal disease, lung disease (chronic pulmonary obstruction, lung cancer), and aging. The concerted action of antioxidants to ameliorate the harmful effect of oxidative stress is achieved by antioxidant enzymes (Superoxide dismutases-SODs, catalase, glutathione peroxidase-GPx), and small molecular weight antioxidants (vitamins C and E, flavonoids, carotenoids, melatonin, ergothioneine, and others). Perhaps one of the most effective low molecular weight antioxidants is vitamin E, the first line of defense against the peroxidation of lipids. A promising approach appears to be the use of certain antioxidants (e.g. flavonoids), showing weak prooxidant properties that may boost cellular antioxidant systems and thus act as preventive anticancer agents. Redox metal-based enzyme mimetic compounds as potential pharmaceutical interventions and sirtuins as promising therapeutic targets for age-related diseases and anti-aging strategies are discussed.


Assuntos
Antioxidantes , Estresse Oxidativo , Humanos , Espécies Reativas de Oxigênio , Doença Crônica
8.
J Enzyme Inhib Med Chem ; 38(1): 2237209, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37489050

RESUMO

Phosphoinositide 3-kinases (PI3K) and phosphoinositide 3-kinase-related protein kinases (PIKK) are two structurally related families of kinases that play vital roles in cell growth and DNA damage repair. Dysfunction of PIKK members and aberrant stimulation of the PI3K/AKT/mTOR signalling pathway are linked to a plethora of diseases including cancer. In recent decades, numerous inhibitors related to the PI3K/AKT/mTOR signalling have made great strides in cancer treatment, like copanlisib and sirolimus. Notably, most of the PIKK inhibitors (such as VX-970 and M3814) related to DNA damage response have also shown good efficacy in clinical trials. However, these drugs still require a suitable combination therapy to overcome drug resistance or improve antitumor activity. Based on the aforementioned facts, we summarised the efficacy of PIKK, PI3K, and AKT inhibitors in the therapy of human malignancies and the resistance mechanisms of targeted therapy, in order to provide deeper insights into cancer treatment.


Assuntos
Neoplasias , Fosfatidilinositol 3-Quinase , Humanos , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinase/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
9.
Arch Toxicol ; 97(8): 2089-2109, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37335314

RESUMO

Cellular senescence leads to decreased tissue regeneration and inflammation and is associated with diabetes, neurodegenerative diseases, and tumorigenesis. However, the mechanisms of cellular senescence are not fully understood. Emerging evidence has indicated that c-Jun N-terminal kinase (JNK) signaling is involved in the regulation of cellular senescence. JNK can downregulate hypoxia inducible factor-1α to accelerate hypoxia-induced neuronal cell senescence. The activation of JNK inhibits mTOR activity and triggers autophagy, which promotes cellular senescence. JNK can upregulate the expression of p53 and Bcl-2 and accelerates cancer cell senescence; however, this signaling also mediates the expression of amphiregulin and PD-LI to achieve cancer cell immune evasion and prevents their senescence. The activation of JNK further triggers forkhead box O expression and its target gene Jafrac1 to extend the lifespan of Drosophila. JNK can also upregulate the expression of DNA repair protein poly ADP-ribose polymerase 1 and heat shock protein to delay cellular senescence. This review discusses recent advances in understanding the function of JNK signaling in cellular senescence and includes a comprehensive analysis of the molecular mechanisms underlying JNK-mediated senescence evasion and oncogene-induced cellular senescence. We also summarize the research progress in anti-aging agents that target JNK signaling. This study will contribute to a better understanding of the molecular targets of cellular senescence and provides insights into anti-aging, which may be used to develop drugs for the treatment of aging-related diseases.


Assuntos
Proteínas Quinases JNK Ativadas por Mitógeno , Transdução de Sinais , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Senescência Celular , Sistema de Sinalização das MAP Quinases , Hipóxia
10.
Front Bioeng Biotechnol ; 11: 1190322, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37304144

RESUMO

Introduction: The objective of current project was to formulate a system for controlled delivery of Tramadol HCl (TRD), an opioid analgesic used in the treatment of moderate to severe pain. Methods: For this purpose, a pH responsive AvT-co-poly hydrogel network was formulated through free radical polymerization by incorporating natural polymers i.e., aloe vera gel and tamarind gum, monomer and crosslinker. Formulated hydrogels were loaded with Tramadol HCl (TRD) and evaluated for percent drug loading, sol-gel fraction, dynamic and equilibrium swelling, morphological characteristics, structural features and in-vitro release of Tramadol HCl. Results and Discussions: Hydrogels were proved to be pH sensitive as remarkable dynamic swelling response ranging within 2.94g/g-10.81g/g was noticed at pH 7.4 as compared to pH 1.2. Percent drug loading was in the range of 70.28%-90.64% for all formulations. Thermal stability and compatibility of hydrogel components were validated by DSC analysis and FTIR spectroscopy. Controlled release pattern of Tramadol HCl from the polymeric network was confirmed as maximum release of 92.22% was observed for over a period of 24 hours at pH 7.4. Moreover, oral toxicity studies were also conducted in rabbits to investigate the safety of hydrogels. No evidence of any toxicity, lesions and degeneration was reported, confirming the biocompatibility and safety of grafted system.

11.
Biomed Pharmacother ; 165: 115022, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37336149

RESUMO

Cells produce reactive oxygen species (ROS) as a metabolic by-product. ROS molecules trigger oxidative stress as a feedback response that significantly initiates biological processes such as autophagy, apoptosis, and necrosis. Furthermore, extensive research has revealed that hydrogen peroxide (H2O2) is an important ROS entity and plays a crucial role in several physiological processes, including cell differentiation, cell signalling, and apoptosis. However, excessive production of H2O2 has been shown to disrupt biomolecules and cell organelles, leading to an inflammatory response and contributing to the development of health complications such as collagen deposition, aging, liver fibrosis, sepsis, ulcerative colitis, etc. Extracts of different plant species, phytochemicals, and Lactobacillus sp (probiotic) have been reported for their anti-oxidant potential. In this view, the researchers have gained significant interest in exploring the potential plants spp., their phytochemicals, and the potential of Lactobacillus sp. strains that exhibit anti-oxidant properties and health benefits. Thus, the current review focuses on comprehending the information related to the formation of H2O2, the factors influencing it, and their pathophysiology imposed on human health. Moreover, this review also discussed the anti-oxidant potential and role of different extract of plants, Lactobacillus sp. and their fermented products in curbing H2O2­induced oxidative stress in both in-vitro and in-vivo models via boosting the anti-oxidative activity, inhibiting of important enzyme release and downregulation of cytochrome c, cleaved caspases-3, - 8, and - 9 expression. In particular, this knowledge will assist R&D sections in biopharmaceutical and food industries in developing herbal medicine and probiotics-based or derived food products that can effectively alleviate oxidative stress issues induced by H2O2 generation.


Assuntos
Antioxidantes , Probióticos , Humanos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Apoptose , Plantas/metabolismo , Probióticos/farmacologia
12.
Pharmacol Res ; 194: 106841, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37385572

RESUMO

Senescent cells persist and continuously secrete proinflammatory and tissue-remodeling molecules that poison surrounding cells, leading to various age-related diseases, including diabetes, atherosclerosis, and Alzheimer's disease. The underlying mechanism of cellular senescence has not yet been fully explored. Emerging evidence indicates that hypoxia is involved in the regulation of cellular senescence. Hypoxia-inducible factor (HIF)- 1α accumulates under hypoxic conditions and regulates cellular senescence by modulating the levels of the senescence markers p16, p53, lamin B1, and cyclin D1. Hypoxia is a critical condition for maintaining tumor immune evasion, which is promoted by driving the expression of genetic factors (such as p53 and CD47) while triggering immunosenescence. Under hypoxic conditions, autophagy is activated by targeting BCL-2/adenovirus E1B 19-kDa interacting protein 3, which subsequently induces p21WAF1/CIP1 as well as p16Ink4a and increases ß-galactosidase (ß-gal) activity, thereby inducing cellular senescence. Deletion of the p21 gene increases the activity of the hypoxia response regulator poly (ADP-ribose) polymerase-1 (PARP-1) and the level of nonhomologous end joining (NHEJ) proteins, repairs DNA double-strand breaks, and alleviates cellular senescence. Moreover, cellular senescence is associated with intestinal dysbiosis and an accumulation of D-galactose derived from the gut microbiota. Chronic hypoxia leads to a striking reduction in the amount of Lactobacillus and D-galactose-degrading enzymes in the gut, producing excess reactive oxygen species (ROS) and inducing senescence in bone marrow mesenchymal stem cells. Exosomal microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) play important roles in cellular senescence. miR-424-5p levels are decreased under hypoxia, whereas lncRNA-MALAT1 levels are increased, both of which induce cellular senescence. The present review focuses on recent advances in understanding the role of hypoxia in cellular senescence. The effects of HIFs, immune evasion, PARP-1, gut microbiota, and exosomal mRNA in hypoxia-mediated cell senescence are specifically discussed. This review increases our understanding of the mechanism of hypoxia-mediated cellular senescence and provides new clues for anti-aging processes and the treatment of aging-related diseases.


Assuntos
Galactose , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/metabolismo , Galactose/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Senescência Celular , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Hipóxia
13.
J Inorg Biochem ; 245: 112244, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37178556

RESUMO

The antioxidant properties of flavonoids are mediated by their functional hydroxyl groups, which are capable of both chelating redox active metals such as iron, copper and scavenging free radicals. In this paper, the antioxidant vs. prooxidant and DNA protecting properties of baicalein and Cu(II)-baicalein complexes were studied under the conditions of the Copper-Fenton reaction and of the Copper-Ascorbate system. From the relevant EPR spectra, the interaction of baicalein with Cu(II) ions was confirmed, while UV-vis spectroscopy demonstrated a greater stability over time of Cu(II)-baicalein complexes in DMSO than in methanol and PBS and Phosphate buffers. An ABTS study confirmed a moderate ROS scavenging efficiency, at around 37%, for both free baicalein and Cu(II)-baicalein complexes (in the ratios 1:1 and 1:2). The results from absorption titrations are in agreement with those from viscometric studies and confirmed that the binding mode between DNA and both free baicalein and Cu-baicalein complexes, involves hydrogen bonds and van der Waals interactions. The DNA protective effect of baicalein has been investigated by means of gel electrophoresis under the conditions of the Cu-catalyzed Fenton reaction and of the Cu-Ascorbate system. In both cases, it was found that, at sufficiently high concentrations, baicalein offers some protection to cells from DNA damage caused by ROS (singlet oxygen, hydroxyl radicals and superoxide radical anions). Accordingly, baicalein may be useful as a therapeutic agent in diseases with a disturbed metabolism of redox metals such as copper, for example Alzheimer's disease, Wilson's disease and various cancers. While therapeutically sufficient concentrations of baicalein may protect neuronal cells from Cu-Fenton-induced DNA damage in regard to neurological conditions, conversely, in the case of cancers, low concentrations of baicalein do not inhibit the pro-oxidant effect of copper ions and ascorbate, which can, in turn, deliver an effective damage to DNA in tumour cells.


Assuntos
Antioxidantes , Cobre , Antioxidantes/química , Cobre/química , Flavonoides , Espécies Reativas de Oxigênio/metabolismo , Ácido Ascórbico , Oxirredução , Metais , Radical Hidroxila/metabolismo , DNA/metabolismo , Dano ao DNA
14.
Food Res Int ; 167: 112690, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087212

RESUMO

The genetic variant A2 ß-casein integrates the casein protein group in milk and has been often associated with positive health outcomes. Therefore, this review explores the present understanding of A2 ß-casein, including detection methods and the market trends for dairy from A2 milk. Also, the interaction of A2 ß-casein with αs1-casein and κ-casein genotypes was examined in terms of technological impacts on A2 milk. A limited number of preliminary studies has aimed to investigate the sensorial and technological impacts of ß-casein variants in milk matrices, for instance, in yogurt and other derivatives. Nevertheless, considering studies carried out so far, it is concluded that the manufacture of dairy products from A2 milk is perfectly feasible, as the products presented slight differences when compared to those derived from traditional milk. In one of the works, sensitive drops in rennet coagulation time and curd firmness values were observed in cheese traits. However, it is relevant to point out that variant A of κ-casein plays a negative role in the coagulation features of milk. Therefore, alterations in the pattern of cheese-making properties are not uniquely related to ß-casein variants. Attempts to produce A2 ß-casein in laboratory (non-natural source), through biosynthesis, for example, have not been found so far. This knowledge gap offers a promising area for future studies concerning proteins and bioactive peptide production.


Assuntos
Queijo , Leite , Animais , Bovinos , Feminino , Leite/química , Caseínas/análise , Genótipo , Fenótipo
15.
Arch Toxicol ; 97(2): 393-404, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36434400

RESUMO

Mycotoxins induce oxidative stress, hypoxia, and cause immunosuppressive effects. Moreover, emerging evidence show that mycotoxins have a potential of inducing cellular senescence, which are involved in their immunomodulatory effects. Mycotoxins upregulate the expression of senescence markers γ-H2AX, senescence-associated ß-galactosidase, p53, p16, and senescence-associated secretory phenotype (SASP) inflammatory factors. Moreover, mycotoxins cause senescence-associated cell cycle arrest by diminishing cyclin D1 and Cdk4 pathways, as well as increasing the expression of p53, p21, and CDK6. Mycotoxins may induce cellular senescence by activating reactive oxygen species (ROS)-induced oxidative stress. In addition, hypoxia acts as a double-edged sword on cell senescence; it could both act as the stress-induced senescence and also hinder the onset of cellular senescence. The SASP inflammatory factors have the ability to induce an immunosuppressive environment, while mycotoxins directly cause immunosuppression. Therefore, there is a potential relationship between mycotoxins and cellular senescence that synergistically cause immunosuppression. However, most of the current studies have involved the effect of mycotoxins on cell cycle arrest, but only limited in-depth research has been carried out to link the occurrence of this condition (cell cycle arrest) with cellular senescence.


Assuntos
Senescência Celular , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/metabolismo , Estresse Oxidativo , Terapia de Imunossupressão , Hipóxia
16.
Biomed Pharmacother ; 156: 113898, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36274463

RESUMO

Medicinal plants have been exploited for therapeutic purposes since the dawn of civilization and have long been acknowledged essential to human health. The purpose of this research is to examine the scientific evidence for using the therapeutic herbal plants Thalictrum foliolosum DC. and Cordia dichotoma G. Forst. to treat hepatitis illness. The fundamental explanation for the therapeutic relevance of these plants is phytochemicals, which were evaluated qualitatively and quantitatively in three separate extracts with different solvent properties (methanol-polar, chloroform-non-polar, and aqueous-polar as one of the bases of traditional use). Flavonoids, phenols, tannins, saponins, and alkaloids were all evaluated for their presence in plant extracts, and it was observed that methanolic extract had the highest content of phytochemicals among different extracts whereas, the aqueous extract showed least amount of phytochemicals. Additionally, the antioxidant activity of these plants was also evaluated and methanolic extract was revealed with potential antioxidant activity, as also evidenced by the lowest half inhibitory concentration (IC50) values in the DPPH, ABTS, and high %inhibition in µM Fe equivalent of FRAP assays. Following that, the dominant phytochemicals were investigated using ultra-high performance liquid chromatography from the selected plants. Furthermore, default docking algorithms were used to appraise the dominant phytoconstituents for their in-silico investigation, in which rutin was found with the highest binding affinity (8.2 kcal/mol) and interaction with receptor which is further involved in causing jaundice. The receptor is infact an enzyme that is sphingomyelin phosphodiesterase Leptospira interrogans (PDB: 5EBB) which is holded back in its position by rutin and do not interact with Leptospira inferrogans spp which causes jaundice. Overall, the study suggested that these herbs have significant therapeutic properties, and their in-silico analysis strongly recommends further clinical investigations to get insight into the mechanisms of action in curing variety of diseases.


Assuntos
Cordia , Icterícia , Thalictrum , Humanos , Antioxidantes/farmacologia , Antioxidantes/análise , Simulação de Dinâmica Molecular , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Flavonoides/farmacologia , Flavonoides/análise , Metanol , Rutina
17.
Biomed Pharmacother ; 153: 113400, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36076525

RESUMO

Cordia dichotoma, Indian cherry is one of the traditional medicinal plant well-known for its medicinal properties against variety of diseases primarily hepatocellular disorders. C. dichotoma is moderate size tree that may be found throughout the Himachal Pradesh and commonly called as lashuda. The objective of the present study is to emphasize the phytochemical and pharmacological study with hepatocurative assessment of C. dichotoma to strengthen not only traditional knowledge but also to validate scientific value of its medicinal potential. Furthermore, comprehensive literature information of C. dichotoma has been compiled from the variety of sources, including scientific databases like PubMed and Google Scholar and pertinent publications and books. The information provided in this study covers the years from 1956 to 2021 and KingDraw chemical structure editor software was used to depict the chemical structures of various secondary metabolites such as flavonoids, tannins, alkaloids, proteins carbohydrate and phenolic compounds extracted from the different parts of the C. dichotoma. Although, flavonoids and phenolic compounds are the most prominent phytoconstituents predominantly detected in C. dichotoma, which are known for great antioxidant potential and also they are renowned for their various pharmacological and therapeutic efficiency against various chronic diseases. Overall, the studies included in this review implies that the plant and its extracts have significant therapeutic benefits not only for hepatic but also for a variety of diseases. While further research is required to fully understand the processes underlying C. dichotoma application in various pharmacological activities.


Assuntos
Cordia , Plantas Medicinais , Cordia/química , Flavonoides , Fenóis , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Plantas Medicinais/química
18.
Chem Biol Interact ; 367: 110173, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36152810

RESUMO

In total, twenty elements appear to be essential for the correct functioning of the human body, half of which are metals and half are non-metals. Among those metals that are currently considered to be essential for normal biological functioning are four main group elements, sodium (Na), potassium (K), magnesium (Mg), and calcium (Ca), and six d-block transition metal elements, manganese (Mn), iron (Fe), cobalt (Co), copper (Cu), zinc (Zn) and molybdenum (Mo). Cells have developed various metallo-regulatory mechanisms for maintaining a necessary homeostasis of metal-ions for diverse cellular processes, most importantly in the central nervous system. Since redox active transition metals (for example Fe and Cu) may participate in electron transfer reactions, their homeostasis must be carefully controlled. The catalytic behaviour of redox metals which have escaped control, e.g. via the Fenton reaction, results in the formation of reactive hydroxyl radicals, which may cause damage to DNA, proteins and membranes. Transition metals are integral parts of the active centers of numerous enzymes (e.g. Cu,Zn-SOD, Mn-SOD, Catalase) which catalyze chemical reactions at physiologically compatible rates. Either a deficiency, or an excess of essential metals may result in various disease states arising in an organism. Some typical ailments that are characterized by a disturbed homeostasis of redox active metals include neurological disorders (Alzheimer's, Parkinson's and Huntington's disorders), mental health problems, cardiovascular diseases, cancer, and diabetes. To comprehend more deeply the mechanisms by which essential metals, acting either alone or in combination, and/or through their interaction with non-essential metals (e.g. chromium) function in biological systems will require the application of a broader, more interdisciplinary approach than has mainly been used so far. It is clear that a stronger cooperation between bioinorganic chemists and biophysicists - who have already achieved great success in understanding the structure and role of metalloenzymes in living systems - with biologists, will access new avenues of research in the systems biology of metal ions. With this in mind, the present paper reviews selected chemical and biological aspects of metal ions and their possible interactions in living systems under normal and pathological conditions.


Assuntos
Manganês , Metaloproteínas , Cálcio/química , Catalase , Cromo , Cobalto , Cobre , Humanos , Íons , Ferro , Magnésio , Molibdênio , Potássio , Sódio , Superóxido Dismutase , Zinco/química
19.
3 Biotech ; 12(9): 190, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35910287

RESUMO

An innovative amperometric immunosensor has been developed to detect antibiotic colistin from the chicken liver. Colistin is a antibacterial peptide that has been barred for human consumption, but it is being commonly used as a veterinary drug, and as a feed additive for livestock. In the present work, an immunosensor was developed by immobilizing an anti-colistin Ab onto the CNF/AuNPs surface of the screen-printed electrode. The sensor records electrochemical response in the chicken liver spiked with colistin with CV. Additionally, the characterization of electrode surface was done with FE-SEM, FTIR, and EIS at each step of fabrication. The lower LOD was 0.89 µgKg-1, with a R 2 of 0.901 using CV. Further validation of the immunosensor was conducted using commercial chicken liver samples, by comparing the results to those obtained using traditional methods. The fabricated immunosensor showed high specificity towards colistin, which remained stable for 6 months but with a 13% loss in the initial CV current.

20.
Appl Microbiol Biotechnol ; 106(13-16): 4831-4843, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35781838

RESUMO

Aging is a progressive, unalterable physiological degradation process of living organisms, which leads to deterioration of biological function and eventually to senescence. The most prevalent factor responsible for aging is the accumulation of damages resulting from oxidative stress and dysbiosis. D-galactose-induced aging has become a hot topic, and extensive research is being conducted in this area. Published literature has reported that the continuous administration of D-galactose leads to the deterioration of motor and cognitive skills, resembling symptoms of aging. Hence, this procedure is employed as a model for accelerated aging. This review aims to emphasize the effect of D-galactose on various bodily organs and underline the role of the Lactobacillus sp. in the aging process, along with its anti-oxidative potential. A critical consideration to the literature describing animal models that have used the Lactobacillus sp. in amending D-galactose-induced aging is also given. KEY POINTS: • D-Galactose induces the aging process via decreasing the respiratory chain enzyme activity as well as ATP synthesis, mitochondrial dysfunction, and increased ROS production. • D-Galactose induced aging primarily affects the brain, heart, lung, liver, kidney, and skin. • The anti-oxidative potential of Lactobacillus sp. in improving D-galactose-induced aging in animal models via direct feeding and feeding of Lactobacillus-fermented food.


Assuntos
Antioxidantes , Galactose , Envelhecimento , Animais , Antioxidantes/metabolismo , Lactobacillus/metabolismo , Estresse Oxidativo
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