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1.
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
2.
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
3.
Molecules ; 28(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36985439

RESUMO

Shigellosis is a serious foodborne diarrheal disease caused by the Shigella species. It is a critical global health issue. In developing countries, shigellosis causes most of the mortality in children below 5 years of age. Globally, around 165 million cases of diarrhea caused by Shigella are reported, which accounts for almost 1 million deaths, in which the majority are recorded in Third World nations. In this study, silver nanoparticles were synthesized using Mangifera indica kernel (MK-AgNPs) seed extracts. The biosynthesized M. indica silver nanoparticles (MK-AgNPs) were characterized using an array of spectroscopic and microscopic tools, such as UV-Vis, scanning electron microscopy, particle size analyzer, Fourier transform infrared spectroscopy, and X-ray diffractometer. The nanoparticles were spherical in shape and the average size was found to be 42.7 nm. The MK-AgNPs exhibited remarkable antibacterial activity against antibiotic-resistant clinical Shigella sp. The minimum inhibitory concentration (MIC) value of the MK-AgNPs was found to be 20 µg/mL against the multi-drug-resistant strain Shigella flexneri. The results clearly demonstrate that MK-AgNPs prepared using M. indica kernel seed extract exhibited significant bactericidal action against pathogenic Shigella species. The biosynthesized nanoparticles from mango kernel could possibly prove therapeutically useful and effective in combating the threat of shigellosis after careful investigation of its toxicity and in vivo efficacy.


Assuntos
Disenteria Bacilar , Mangifera , Nanopartículas Metálicas , Shigella , Criança , Humanos , Mangifera/química , Nanopartículas Metálicas/química , Prata/farmacologia , Prata/química , Disenteria Bacilar/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia , Antibacterianos/química , Sementes
4.
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
5.
J Transl Med ; 19(1): 166, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902635

RESUMO

OBJECTIVES: Vitamin D status in patients with COVID-19 is an on-going controversial issue. This study aims to determine differences in the serum 25(OH)D concentrations of Arab Gulf adult residents screened for SARS-CoV-2 and its association with risk of COVID-19 infection together with other comorbidities. METHODS: In this multi-center, case-control study, a total of 220 male and female adults presenting with none to mild symptoms were screened for COVID-19 (n = 138 RT-PCR-confirmed SARS-CoV-2 positive and 82 negative controls). Medical history was noted. Anthropometrics were measured and non-fasting blood samples were collected for the assessment of glucose, lipids, inflammatory markers and serum 25(OH)D concentrations. RESULTS: Serum 25(OH)D levels were significantly lower in the SARS-CoV-2 positive group compared to the negative group after adjustment for age and BMI (52.8 nmol/l ± 11.0 versus 64.5 nmol/l ± 11.1; p = 0.009). Being elderly (> 60 years) [Odds ratio 6 (95% Confidence Interval, CI 2-18; p = 0.001) as well as having type 2 diabetes (T2D) [OR 6 (95% CI 3-14); p < 0.001)] and low HDL cholesterol (HDL-c) [OR 6 (95% CI 3-14); p < 0.001)] were significant risk factors for COVID-19 infection independent of age, sex and obesity. CONCLUSIONS: Among Arab Gulf residents screened for SARS-CoV-2, serum 25(OH) D levels were observed to be lower in those who tested positive than negative individuals, but it was the presence of old age, diabetes mellitus and low-HDL-c that were significantly associated with risk of COVID-19 infection. Large population-based randomized controlled trials should be conducted to assess the protective effects of vitamin D supplementation against COVID-19.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Adulto , Idoso , Árabes , Estudos de Casos e Controles , Feminino , Humanos , Masculino , SARS-CoV-2 , Vitamina D
6.
Int J Mol Sci ; 22(10)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34069111

RESUMO

In colon cancer, wingless (Wnt)/ß-catenin signaling is frequently upregulated; however, the creation of a molecular therapeutic agent targeting this pathway is still under investigation. This research aimed to study how nitazoxanide can affect Wnt/ß-catenin signaling in colon cancer cells (HCT-116) and a mouse colon cancer model. Our study included 2 experiments; the first was to test the cytotoxic activity of nitazoxanide in an in vitro study on a colon cancer cell line (HCT-116) versus normal colon cells (FHC) and to highlight the proapoptotic effect by MTT assay, flow cytometry and real-time polymerase chain reaction (RT-PCR). The second experiment tested the in vivo cytotoxic effect of nitazoxanide against 1,2-dimethylhydrazine (DMH) prompted cancer in mice. Mice were grouped as saline, DMH control and DMH + nitazoxanide [100 or 200 mg per kg]. Colon levels of Wnt and ß-catenin proteins were assessed by Western blotting while proliferation was measured via immunostaining for proliferating cell nuclear antigen (PCNA). Treating HCT-116 cells with nitazoxanide (inhibitory concentration 50 (IC50) = 11.07 µM) revealed that it has a more cytotoxic effect when compared to 5-flurouracil (IC50 = 11.36 µM). Moreover, it showed relatively high IC50 value (non-cytotoxic) against the normal colon cells. Nitazoxanide induced apoptosis by 15.86-fold compared to control and arrested the cell cycle. Furthermore, nitazoxanide upregulated proapoptotic proteins (P53 and BAX) and caspases but downregulated BCL-2. Nitazoxanide downregulated Wnt/ß-catenin/glycogen synthase kinase-3ß (GSK-3ß) signaling and PCNA staining in the current mouse model. Hence, our findings highlighted the cytotoxic effect of nitazoxanide and pointed out the effect on Wnt/ß-catenin/GSK-3ß signaling.


Assuntos
Antiparasitários/farmacologia , Neoplasias do Colo/tratamento farmacológico , Nitrocompostos/farmacologia , Tiazóis/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Antiparasitários/química , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HCT116 , Humanos , Masculino , Camundongos , Simulação de Acoplamento Molecular , Nitrocompostos/química , Antígeno Nuclear de Célula em Proliferação/imunologia , Antígeno Nuclear de Célula em Proliferação/metabolismo , Tiazóis/química , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
7.
Molecules ; 25(14)2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679837

RESUMO

OBJECTIVES: The aim of this study was to prepare doxycycline polymeric nanoparticles (DOXY-PNPs) with hope to enhance its chemotherapeutic potential against solid Ehrlich carcinoma (SEC). METHODS: Three DOXY-PNPs were formulated by nanoprecipitation method using hydroxypropyl methyl cellulose (HPMC) as a polymer. The prepared DOXY-PNPs were evaluated for the encapsulation efficiency (EE%), the drug loading capacity, particle size, zeta potential (ZP) and the in-vitro release for selection of the best formulation. PNP number 3 was selected for further biological testing based on the best pharmaceutical characters. PNP3 (5 and 10 mg/kg) was evaluated for the antitumor potential against SEC grown in female mice by measuring the tumor mass as well as the expression and immunohistochemical staining for the apoptosis markers; caspase 3 and BAX. RESULTS: The biological study documented the greatest reduction in tumor mass in mice treated with PNP3. Importantly, treatment with 5 mg/kg of DOXY-PNPs produced a similar chemotherapeutic effect to that produced by 10 mg/kg of free DOXY. Further, a significant elevation in mRNA expression and immunostaining for caspase 3 and BAX was detected in mice group treated with DOXY-PNPs. CONCLUSIONS: The DOXY-PNPs showed greater antitumor potential against SEC grown in mice and greater values for Spearman's correlation coefficients were detected when correlation with tumor mass or apoptosis markers was examined; this is in comparison to free DOXY. Hence, DOXY-PNPs should be tested in other tumor types to further determine the utility of the current technique in preparing chemotherapeutic agents and enhancing their properties.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Doxiciclina/síntese química , Doxiciclina/farmacologia , Nanopartículas/química , Polímeros/química , Animais , Antineoplásicos/química , Caspase 3/metabolismo , Doxiciclina/química , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Feminino , Imuno-Histoquímica , Camundongos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Relação Estrutura-Atividade
8.
Cytokine ; 110: 189-193, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29775920

RESUMO

Expression of GPCR fatty acid sensor/receptor genes in adipocytes is modulated by inflammatory mediators, particularly IL-1ß. In this study we examined whether the IL-1 gene superfamily member, IL-33, also regulates expression of the fatty acid receptor genes in adipocytes. Human fat cells, differentiated from preadipocytes, were incubated with IL-33 at three different dose levels for 3 or 24 h and mRNA measured by qPCR. Treatment with IL-33 induced a dose-dependent increase in GPR84 mRNA at 3 h, the level with the highest dose being 13.7-fold greater than in controls. Stimulation of GPR84 expression was transitory; the mRNA level was not elevated at 24 h. In contrast to GPR84, IL-33 had no effect on GPR120 expression. IL-33 markedly stimulated expression of the IL1B, CCL2, IL6, CXCL2 and CSF3 genes, but there was no effect on ADIPOQ expression. The largest effect was on CSF3, the mRNA level of which increased 183-fold over controls at 3 h with the highest dose of IL-33; there was a parallel increase in the secretion of G-CSF protein into the medium. It is concluded that in human adipocytes IL-33, which is synthesised in adipose tissue, has a strong stimulatory effect on the expression of cytokine and chemokine genes, particularly CSF3, and on the expression of GPR84, a pro-inflammatory fatty acid receptor.


Assuntos
Adipócitos/metabolismo , Quimiocinas/genética , Citocinas/genética , Interleucina-33/genética , Receptores de Superfície Celular/genética , Adiponectina/genética , Tecido Adiposo/metabolismo , Células Cultivadas , Ácidos Graxos/genética , Fator Estimulador de Colônias de Granulócitos/genética , Humanos , Interleucina-1beta/genética , Macrófagos/metabolismo , RNA Mensageiro/genética , Receptores Acoplados a Proteínas G , Fator de Necrose Tumoral alfa/genética
9.
Immunogenetics ; 69(2): 69-76, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27631728

RESUMO

Breast cancer (BC) progression and metastases have been linked to antitumor immunity inefficiency and particularly to natural killer (NK) cells. Killer cell immunoglobulin-like receptors (KIRs) are the most polymorphic receptors of NK cells. Through their interactions with human leukocyte antigen (HLA)-C ligands, they modulate NK and T cell actions against target cells. Therefore, we studied the combinatorial effect of KIR genes and their HLA-C ligands on the susceptibility to development of BC in Saudi women. The presence of KIR genes and HLA-C1 and HLA-C2 groups was typed in 50 Saudi patients living in Riyadh and 65 healthy controls using polymerase chain reaction with sequence-specific primers. Our results indicated a protective effect by the KIR2DS2, 2DS3, and 2DL5A genes against BC (OR = 0.25, 0.21, and 0.27, respectively, and p < 0.01). The synergistic action of the three genes was observed when they occurred together, and the absence of the three genes increased BC occurrence by 6.5-fold. Distribution of the HLA-C1/C2 ligand between patients and controls showed an increase in the risk of BC occurrence for the heterozygote C1/C2 (OR = 2.33; 95 % CI = 1.08-5.02; p = 0.037) and a protective effect of the homozygote C2C2 (OR = 0.03; 95 % CI = 0.009-0.098; p < 0.001). Combinatory analyses of KIR genes and their HLA-C ligands showed protective effects of KIR2DL2 and 2DL3 in the absence of their HLA-C1 ligand. These results suggested that KIR-gene content combined with their ligand could influence the risk of BC development in women in Saudi Arabia.


Assuntos
Neoplasias da Mama/genética , Variação Genética/genética , Antígenos HLA-C/genética , Receptores KIR/genética , Adulto , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/imunologia , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Reação em Cadeia da Polimerase , Arábia Saudita/epidemiologia
10.
Curr Res Food Sci ; 9: 100836, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39290651

RESUMO

The resurgence of interest in amaranth and buckwheat as nutrient-rich and versatile grains has incited extensive research aimed at exploring their potential benefits for sustainable agriculture and human nutrition. Amaranth is renowned for its gluten-free nature and exceptional nutritional profile, offering high-quality proteins, fiber, minerals, and bioactive compounds. Similarly, buckwheat is recognized for its functional and nutraceutical properties, offering a plethora of health benefits attributed to its diverse array of biologically active constituents; flavonoids, phytosterols, and antioxidants. This comprehensive review comprehends the existing understanding of the composition, anti-nutritional factors, biological activity, and potential application of these grains, emphasizing their pivotal role in addressing global food insecurity. Developed functional foods using these grains are having enhanced physicochemical properties, mineral content, phenolic content and overall sensory acceptability. In addition, the consumption of developed functional food products proved their health benefits against various type of anomalies. Moreover, enrichment of both grains in the animal feeds also showing positive health benefits.

11.
Curr Res Food Sci ; 9: 100791, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38979544

RESUMO

The utmost objective of every nation is to achieve zero hunger and ensure the health and well-being of its population. However, in impoverished nations, particularly in rural areas, such issues persist on a daily basis. Currently, there is a growing demand for fruit consumption due to their potential health benefits. Surprisingly, their most prevalent by-product is pomace, which is produced in millions of tonnes and is usually discarded as waste after processing or consumption. Even food produced with these kinds of raw resources can contribute to the objective of eradicating world hunger. Owing to these advantages, scientists have begun evaluating the nutritional content of various fruit pomace varieties as well as the chemical composition in different bioactive constituents, which have significant health benefits and can be used to formulate a variety of food products with notable nutraceutical and functional potential. So, the purpose of this review is to understand the existing familiarity of nutritional and phytochemical composition of selected fruit pomaces, those derived from pineapple, orange, grape, apple, and tomato. Furthermore, this article covers pre-clinical and clinical investigations conducted on the selected fruit pomace extracts and/or powder forms and its incorporation into food products and animal feed. Adding fruit pomaces reduces the glycemic index, increases the fibre content and total polyphenolic contents, and reduces the cooking loss, etc. In animal feeds, incorporating fruit pomaces improves the antioxidant enzyme activities, humoral immune system, and growth performance and reduces methane emission.

12.
Sci Total Environ ; 922: 171142, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38387576

RESUMO

Global imperatives have recently shown a paradigm shift in the prevailing resource utilization model from a linear approach to a circular bioeconomy. The primary goal of the circular bioeconomy model is to minimize waste by effective re-usage of organic waste and efficient nutrient recycling. In essence, circular bioeconomy integrates the fundamental concept of circular economy, which strives to offer sustainable goods and services by leveraging biological resources and processes. Notably, the circular bioeconomy differs from conventional waste recycling by prioritizing the safeguarding and restoration of production ecosystems, focusing on harnessing renewable biological resources and their associated waste streams to produce value-added products like food, animal feed, and bioenergy. Amidst these sustainability efforts, fruit seeds are getting considerable attention, which were previously overlooked and commonly discarded but were known to comprise diverse chemicals with significant industrial applications, not limited to cosmetics and pharmaceutical industries. While, polyphenols in these seeds offer extensive health benefits, the inadequate conversion of fruit waste into valuable products poses substantial environmental challenges and resource wastage. This review aims to comprehend the known information about the application of non-edible fruit seeds for synthesising metallic nanoparticles, carbon dots, biochar, biosorbent, and biodiesel. Further, this review sheds light on the potential use of these seeds as functional foods and feed ingredients; it also comprehends the safety aspects associated with their utilization. Overall, this review aims to provide a roadmap for harnessing the potential of non-edible fruit seeds by adhering to the principles of a sustainable circular bioeconomy.


Assuntos
Ecossistema , Frutas , Animais , Sementes , Reciclagem , Polifenóis , Biocombustíveis
13.
Toxicology ; 492: 153549, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37209941

RESUMO

Serious health risks associated with the consumption of food products contaminated with aflatoxins (AFs) are worldwide recognized and depend predominantly on consumed AF concentration by diet. A low concentration of aflatoxins in cereals and related food commodities is unavoidable, especially in subtropic and tropic regions. Accordingly, risk assessment guidelines established by regulatory bodies in different countries help in the prevention of aflatoxin intoxication and the protection of public health. By assessing the maximal levels of aflatoxins in food products which are a potential risk to human health, it's possible to establish appropriate risk management strategies. Regarding, a few factors are crucial for making a rational risk management decision, such as toxicological profile, adequate information concerning the exposure duration, availability of routine and some novel analytical techniques, socioeconomic factors, food intake patterns, and maximal allowed levels of each aflatoxin in different food products which may be varied between countries.


Assuntos
Aflatoxinas , Contaminação de Alimentos , Humanos , Contaminação de Alimentos/prevenção & controle , Aflatoxinas/toxicidade , Aflatoxinas/análise , Aflatoxinas/metabolismo , Dieta , Medição de Risco , Alimentos
14.
Sci Rep ; 13(1): 15075, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37699974

RESUMO

Human Papillomavirus (HPV) is the most common cause of sexually transmitted diseases and causes a wide range of pathologies including cervical carcinoma. Integration of the HR-HPV DNA into the host genome plays a crucial role in cervical carcinoma. An alteration of the pRb pathways by the E7 proteins is one of the mechanisms that's account for the transforming capacity of high-risk papillomavirus. For the proper understanding of the underline mechanism of the progression of the disease, the present study investigate the correlation of concentration of host pRb protein, viral E7 oncoprotein and viral load in early and advanced stages of cervical carcinoma. It was found that the viral load in early stages (stage I and II) was less (log10 transformed mean value 2.6 and 3.0) compared to advanced stages (stage III and IV) (Log10 transformed value 5.0 and 5.8) having high expression of HPV E7 onco-protein and reduced level of pRb protein, signifying the role of viral load and expression level of E7 oncoprotein in the progression of cervical cancer.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Papillomavirus Humano , Infecções por Papillomavirus/complicações , Carga Viral , Proteínas E7 de Papillomavirus/genética
15.
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
16.
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
17.
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
18.
Environ Sci Pollut Res Int ; 29(29): 43546-43555, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35396684

RESUMO

Schistosomiasis, also known as snail fever or bilharziasis, is a worm infection caused by trematode called schistosomes that affects humans and animals worldwide. Schistosomiasis endemically exists in developing countries. Inflammatory responses elicited in the early phase of infection represent the rate limiting step for parasite migration and pathogenesis and could be a valuable target for therapeutic interventions. Prostaglandin E2 (PGE2) and interleukin (IL)-10 were found to be differentially affected in case of immune-modulation studies and cytokine analysis of hosts infected with either normal or radiation-attenuated parasite (RA) which switches off the development of an effective immune response against the migrating parasite in the early phase of schistosomiasis. Normal parasites induce predominantly a T helper 2 (Th2)-type cytokine response (IL-4 and IL-5) which is essential for parasite survival; here, we discuss in detail the downstream effects and cascades of inflammatory signaling of PGE2 and IL10 induced by normal parasites and the effect of blocking PGE2 receptors. We suggest that by selectively constraining the production of PGE2 during vaccination or therapy of susceptible persons or infected patients of schistosomiasis, this would boost IL-12 and reduce IL-10 production leading to a polarization toward the anti-worm Thl cytokine synthesis (IL-2 and Interferon (IFN)-γ).


Assuntos
Dinoprostona , Esquistossomose , Animais , Citocinas , Dinoprostona/farmacologia , Humanos , Imunidade , Interferon gama , Larva
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.
Mol Syndromol ; 13(2): 117-122, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35414808

RESUMO

Polycystic ovary syndrome (PCOS) is a considered one of the most common female disorders associated with reproductive, metabolic, and psychological problems. The etiology of PCOS is still not yet disclosed; however, evidence for a genetic basis has been reported. In this study, we investigate the associations between superoxide dismutase 2 (SOD2) (rs4880) and paraoxonase 1 (PON1) (rs705379) polymorphisms in PCOS in Saudi women. The study included 99 females with PCOS and 98 healthy women as a control. Single nucleotide polymorphisms (SNPs) of promoter regions were determined using TaqMan genotyping assays. Regarding the polymorphism at SOD2 (rs4880), the CC, CT, and TT genotypes were present at rates of 32, 61, and 7% in PCOS patients, and 47, 43, and 10% in controls, respectively. The frequency of the CT genotype in PCOS patients (0.61) was significantly higher than in controls (0.43) (OR = 2.05, CI: 1.16-3.61; p = 0.015). The wild homozygous genotype (CC) with the phenotype alanine appears to confer protection against the disease compared to molecules sharing at least one valine (genotypes, CT + TT). Regarding the polymorphism at PON1 (rs705379), the rates of CC, CT, and TT genotypes were 34, 50, and 16% in PCOS patients and 33, 63, and 2% in controls, respectively. The rate of the TT genotype in PCOS patients was significantly higher than that in controls (p = 0.0058). SOD2 and PON1 polymorphisms may be genetic factors that affect the occurrence of PCOS in Saudi females.

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