Injectable Hydrogel Containing TiO Nanosheets for Synergistic Photothermal/Thermodynamic Therapy.

Tumors have become the biggest obstacle to human health, and there are various treatment methods at present. Photothermal therapy (PTT) is usually ineffective and does not inhibit tumor progression due to the inability of the lasers to penetrate deeply. Therefore, most existing studies chose a 1064 nm laser with stronger penetrating power; meanwhile, studies have shown that the inclusion of harmful free radicals can significantly improve the antitumor efficacy. Herein, TiO nanosheets (NSs) were creatively prepared and encapsulated with an alkyl radical generator {2,2'-azobis[2-(2-imidazoline-2-yl)propane] dihydrochloride, [AIPH]} in sodium alginate (ALG) hydrogel for effective tumor killing by PTT and pairing with dangerous free radicals. TiO NSs were obtained by the liquid-phase exfoliation method, together with AIPH, which were in situ coencapsulated multifunctional hydrogels formed by the combination of Ca2+ and ALG. This ALG hydrogel could enrich TiO NSs and AIPH at the tumor site for a long time, and through the excellent photothermal properties of TiO NSs, AIPH could slowly and effectively generate alkyl radicals at the tumor site, which, in turn, gave it a better antitumor effect compared with that of TiO NSs in the deep hypoxic environment of the tumor. The AIPH + TiO + ALG hydrogel has distinctive anticancer capabilities based on the results of both in vivo and in vitro experiments. This material also has good biosafety. By combining PTT and free radical treatment, this work provides a novel therapeutic method to achieve oxygen-independent free radical production and enhance therapeutic efficacy.

Isolated Natural Antioxidants as a new Possible Therapeutic Alternative for the Treatment of Hypertension.

Oxidative stress is one of the main mechanisms involved in the pathophysiology of arterial hypertension, inducing direct effects on the vasculature, and contributing to endothelial dysfunction and consequent impairment of vascular relaxation. Despite a large number of pharmacological treatments available, intolerable side effects are reported, which makes the use of natural antioxidants a promising and complementary alternative for the prevention and treatment of hypertension. From this perspective, the current review aims to investigate and characterize the main antioxidants of natural origin for the treatment of hypertension. Antioxidants act in the inhibition or extinction of chemical reactions involving free radicals and consequently reduce the occurrence of damage caused by these cellular components. The main natural antioxidants for treating hypertension include caffeic acid, ferulic acid, curcumin, apocynin, quercetin, lipoic acid, and lycopene. The effects associated with these antioxidants, which make them therapeutic targets for decreasing high blood pressure, include increased activation of antioxidant enzymes, stimulation of nitric oxide bioavailability, and reduction in angiotensin-converting enzyme activity, arginase, and NADPH oxidase, whose effects contribute to reducing oxidative stress, improving endothelial function, and preventing cardiovascular dysfunctions. Thus, several products with antioxidant properties that are available in nature and their application in the treatment of hypertension are described in the literature. The therapeutic effects of these products seem to regulate several parameters related to arterial hypertension, in addition to combating and preventing the deleterious effects related to the disease.

Potential of natural products in the treatment of myocardial infarction: focus on molecular mechanisms.

Although conventional drugs are widely used in the prevention and treatment of cardiovascular disease (CVD), they are being used less frequently due to concerns about possible side effects over the long term. There has been a renewed research interest in medicinal plant products, and their role in protecting the cardiovascular system and treating CVD, which are now being considered as potential alternatives to modern drugs. The most important mechanism causing damage to the myocardium after heart attack and reperfusion, is increased levels of free radicals and oxidative stress. Therefore, treatment approaches often focus on reducing free radicals or enhancing antioxidant defense mechanism. It has been previously reported that bioactive natural products can protect the heart muscle in myocardial infarction (MI). Since these compounds are readily available in fruits and vegetables, they could prevent the risk of MI if they are consumed daily. Although the benefits of a healthy diet are well known, many scientific studies have focused on whether pure natural compounds can prevent and treat MI. In this review we summarize the effects of curcumin, resveratrol, quercitin, berberine, and tanshinone on MI and CVD, and focus on their proposed molecular mechanisms of action.

Evaluating anti-obesity potential, active components, and antioxidant mechanisms of Moringa peregrina seeds extract on high-fat diet-induced obesity.

There are no medical drugs that provide an acceptable weight loss with minimal adverse effects. This study evaluated the Moringa peregrina (MP) seed extract's anti-obesity effect. Twenty-four (6/each group) male Sprague Dawley rats were divided into group Ι (control), group ΙΙ (high-fat diet [HFD]), group ΙΙΙ (HFD+ MP [250 mg/kg b.wt]), and group ΙV (HFD+ MP [500 mg/kg b.wt]). MP administration significantly ameliorated body weight gains and HFD induced elevation in cholesterol, triglycerides, LDL, and reduced HDL. Moreover, MP seed oil showed high free radical-scavenging activity, delayed ß-carotene bleaching and inhibited lipoprotein and pancreatic lipase enzymes. High-performance liquid chromatography (HPLC) revealed three major active components: crypto-chlorogenic acid, isoquercetin, and astragalin. Both quantitative Real-time PCR (RT-PCR) and western blotting revealed that MP seeds oil significantly decreased the expression of lipogenesis-associated genes such as peroxisome proliferator-activated receptors gamma (PPARγ) and fatty acid synthase (FAS) and significantly elevated the expression of lipolysis-associated genes (acetyl-CoA carboxylase1, ACCl). The oil also enhanced phosphorylation of AMP-activated protein kinase alpha (AMPK-α) and suppressed CCAAT/enhancer-binding protein ß (C/EBPß). In conclusion, administration of M. peregrina seeds oil has anti-obesity potential in HFD-induced obesity in rats. PRACTICAL APPLICATIONS: M. peregrina seeds oil had a potential anti-obesity activity that may be attributed to different mechanisms. These included decreasing body weight, and body mass index and improving lipid levels by decreasing total cholesterol, triglycerides and LDL-C, and increasing HDL-C. Also, M. peregrina seeds oil regulated adipogenesis-associated genes, such as downregulating the expression of (PPARγ, C/EBPα, and FAS) and improving and upregulating the expression and phosphorylation of AMPKα and ACCl. Despite that M. peregrina extract has reported clear anti-obesity potential through animal and laboratory studies, the available evidence-based on human clinical trials are very limited. Therefore, further studies are needed that could focus on clinical trials investigating anti-obesity potential different mechanisms of M. peregrina extract in humans.

Morel mushroom, Morchella from Kashmir Himalaya: a potential source of therapeutically useful bioactives that possess free radical scavenging, anti-inflammatory, and arthritic edema-inhibiting activities.

Morel mushrooms, Morchella species are highly nutritious and excellently edible wild mushrooms abundantly growing in Kashmir Himalayas. The free radical scavenging, anti-inflammatory, and arthritis edema-inhibiting properties of bioactive extract of Morchella elata (EAE) were evaluated. EAE inhibited 53.2% formalin-induced paw edema at a dose of 500 mg/kg b.wt and 75.0% croton oil-induced skin inflammation at a dose of 50 mg topical application. EAE exhibited 51.8% COX inhibiting activity at a concentration of 100 µg/ml when assayed using LPS-stimulated RAW 264.7 cells exposed to the extract. NF-kB inhibiting activity of EAE was assayed using Lentix-293T P65 Ds Red stable cell line. High-throughput fluorescent imaging and flow cytometry showed profound ability of EAE to inhibit NF-kB activity. HPTLC analysis revealed that EAE is composed of several chemical components. The mushroom is a source of therapeutically useful functional food that can provide relief in arthritis.

Selenomethionine and Methioninase: Selenium Free Radical Anticancer Activity.

Colloidal selenium, was first used to treat cancer as early as 1911 in both humans and mice. Selenium was identified as the toxic component in forage plants of sheep, cattle, and horses in the 1930s. The animal toxicity of selenium compounds was determined to be from the metabolism by animals of the elevated concentrations of Se-methylselenocysteine and selenomethionine in plants. The metabolism of both Se-methylselenocysteine and selenomethionine by animals gives rise to the metabolite, methylselenide (CH3Se-), which if in sufficient concentration oxidizes thiols and generates superoxide and other reactive oxygen species. Cancer cells that may overly express methionine gamma-lyase, or beta-lyase (methioninase), by induced viral genomic expression, are susceptible to free radical-induced apoptosis from selenomethionine or Se-methylselenocysteine supplementation.

The natural phenolic compounds as modulators of NADPH oxidases in hypertension.

BACKGROUND: Hypertension is a major public health problem worldwide. It is an important risk factor for other cardiovascular diseases such as coronary artery disease, stroke, heart failure, atrial fibrillation, peripheral vascular disease, chronic kidney disease, and atherosclerosis. PURPOSE: There is strong evidence that excess ROS-derived NADPH oxidase (NOX) is an important agent in hypertension. It augments blood pressure in the presence of other pro-hypertensive factors such as angiotensin II (Ang II), an important and potent regulator of cardiovascular NADPH oxidase, activates NOX via AT1 receptors. NADPH oxidase, a multi-subunit complex enzyme, is considered as a key source of ROS production in the vasculature. The activation of this enzyme is needed for assembling Rac-1, p40phox, p47phox and p67phox subunits. Since, hypertensive patients need to control blood pressure for their entire life and because drugs and other chemicals often induce adverse effects, the use of natural phenolic compounds which are less toxic and potentially beneficial may be good avenues of addition research in our understand of the underlying mechanism involved in hypertension. This review focused on several natural phenolic compounds as berberine, thymoquinone, catechin, celastrol, apocynin, resveratrol, curcumin, hesperidine and G-hesperidine, and quercetin which are NOX inhibitors. In addition, structure activity relationship of these compounds eventually as the most inhibitors was discussed. METHODS: This comprehensive review is based on pertinent papers by a selective search using relevant keywords that was collected using online search engines and databases such as ScienceDirect, Scopus and PubMed. The literature mainly focusing on natural products with therapeutic efficacies against hypertension via experimental models both in vitro and in vivo was identified. RESULTS: It has been observed that these natural compounds prevent NADPH oxidase expression and ROS production while increasing NO bioavailability. It have been reported that they improve hypertension due to formation of a stable radical with ROS-derived NADPH oxidase and preventing the assembly of NOX subunites. CONCLUSION: It is clear that natural phenolic compounds have some potential inhibitory effect on NADPH oxidase activity. In comparison to other phenolic plant compounds, the structural variability of the flavonoids should off different impacts on oxidative stress in hypertension including inhibition of nadph oxidase and direct scavenging of free radicals.

PROOXIDANT ACTIVITIES OF ANTIOXIDANTS AND THEIR IMPACT ON HEALTH.

This review article is focused on the impact of antioxidants and prooxidants on health with emphasis on the type of antioxidants that should be taken. Medical researchers suggest that diet may be the solution for the control of chronic diseases such as cardiovascular complications, hypertension, diabetes mellitus, and different cancers. In this survey, we found scientific evidence that the use of antioxidants should be limited only to the cases where oxidative stress has been identified. This is often the case of specific population groups such as postmenopausal women, the elderly, infants, workers exposed to environmental pollutants, and the obese. Before starting any supplementation, it is necessary to measure oxidative stress and to identify and eliminate the possible sources of free radicals and thus increased oxidative stress.

Rottlerin, a polyphenolic compound from the fruits of Mallotus phillipensis (Lam.) Müll.Arg., impedes oxalate/calcium oxalate induced pathways of oxidative stress in male wistar rats.

BACKGROUND: Oxalate and/or calcium oxalate, is known to induce free radical production, subsequently leading to renal epithelial injury. Oxidative stress and mitochondrial dysfunction have emerged as new targets for managing oxalate induced renal injury. HYPOTHESIS: Plant products and antioxidants have gained tremendous attention in the prevention of lithiatic disease. Rottlerin, a polyphenolic compound from the fruits of Mallotus phillipensis (Lam.) Müll.Arg., has shown free radical scavenging, antioxidant activity and has been reported to interfere in signaling pathways leading to inflammation and apoptosis. In this study, the potential role of rottlerin, in rats exposed to hyperoxaluric environment was explored. METHODS: Hyperoxaluria was induced by administering 0.4% ethylene glycol and 1% ammonium chloride in drinking water to male wistar rats for 9 days. Rottlerin was administered intraperitoneally at 1mg/kg/day along with the hyperoxaluric agent. Prophylactic efficacy of rottlerin to diminish hyperoxaluria induced renal dysfunctionality and crystal load was examined along with its effect on free radicals generating pathways in hyperoxaluric rats. RESULTS: 0.4% ethylene glycol and 1% ammonium chloride led to induction of hyperoxaluria, oxiadtive stress and mitochondrial damage in rats. Rottlerin treatment reduced NADPH oxidase activity, prevented mitochondrial dysfunction and maintained antioxidant environment. It also refurbished renal functioning, tissue integrity and diminished urinary crystal load in hyperoxaluric rats treated with rottlerin. CONCLUSIONS: Thus, the present investigation suggests that rottlerin evidently reduced hyperoxaluric consequences and the probable mechanism of action of this drug could be attributed to its ability to quench free radicals by itself and interrupting signaling pathways involved in pathogenesis of stone formation.

Cancer and diet: How are they related?

Extensive research in the past decade has revealed cancer to be a multigenic disease caused by perturbation of multiple cell signalling pathways and dysregulation of numerous gene products, all of which have been linked to inflammation. It is also becoming evident that various lifestyle factors, such as tobacco and alcohol use, diet, environmental pollution, radiation and infections, can cause chronic inflammation and lead to tumourigenesis. Chronic diseases caused by ongoing inflammation therefore require chronic, not acute, treatment. Nutraceuticals, compounds derived from fruits, vegetables, spices and cereals, can be used chronically. This study discusses the molecular targets of some nutraceuticals that happen to be markers of chronic inflammation and how they can prevent or treat cancer. These naturally-occurring agents in the diet have great potential as anti-cancer drugs, thus proving Hippocrates, who proclaimed 25 centuries ago, 'Let food be thy medicine and medicine be thy food'.

Actividad antioxidante de plantas empleadas en la medicina tradicional navarra / No disponible

Numerosos estudios han puesto de manifiesto últimamente la relación existente entre el estrés oxidativo, el envejecimiento celular y algunas enfermedades. El estilo de vida actual está favoreciendo la acumulación de radicales libres y especies reactivas del oxígeno en nuestro organismo y como consecuencia de ello un aumento del estrés oxidativo a nivel fisiológico. Por esto es recomendable el aporte de antioxidantes de carácter exógeno. Debido al interés que están adquiriendo este grupo de compuestos, en este artículo se presenta un trabajo de investigación que tiene por objeto la búsqueda de plantas medicinales con actividad antioxidante a partir de especies vegetales empleadas en la medicina tradicional en Navarra (AU)

Many studies have shown the relation between oxidative stress, cellular senescence and some diseases. In addition, current lifestyle is causing the accumulation of free radicals and reactive oxygen species in the human body increasing the physiological level of oxidative stress. For these reasons it is recommended the intake of exogenous antioxidants. Due to the raising interest of these compounds, this article presents a research work about antioxidant activity of plants used in folk medicine in Navarra (Spain) (AU)

Efectos del extracto de té verde sobre los daños oxidativos inducidos por cisplatino en riñones y testículos de ratas / Effect of green tea extract on cisplatin induced oxidative damage on kidney and testes of rats

Se administró extracto de té verde (Camellia sinensis) por vía oral a las ratas en dosis de 25, 50 y 100 mg/kg para investigar sus efectos sobre la nefrotoxicidad y la toxicidad testicular inducida por cisplatino (3mg/kg). El extracto de té verde restauró el nivel de creatinina, urea, nitrógeno ureico en sangre (NUS) y ácido úrico en el suero de animales tratados con cisplatino en comparación con los animales tratados sólo con cisplatino. Además, se observó que la administración de extracto de té verde restauró los niveles de enzimas antioxidantes como superóxido dismutasa (SOD), catalasa (CAT) y glutatión reducido (GSH), y enzimas ligadas a la membrana como Na Na+K+ATPasa, Ca Ca2+ 2+ ATPasa y Mg Mg2+ 2+ ATPasa y redujo la peroxidación lipídica (MDA) en los riñones y en los testículos de animales con alteraciones tras el tratamiento crónico con cisplatino. Por tanto, se puede concluir que el extracto de té verde posee actividad antioxidante y que, en virtud de esta acción, puede proteger los riñones y los testículos frente a los daños oxidativos inducidos por el cisplatino

Green tea extract (Camellia sinensis) was administered orally to rats at the dose levels of 25, 50,100 mg/kg to investigate its effect on cisplatin (3mg/kg) induced nephrotoxicity and testicular toxicity. Green tea extract restored the level of creatinine, urea, blood urea nitrogen (BUN) and uric acid in serum of animals treated with cisplatin as compared to the animals treated with cisplatin alone. It was further found that administration of green tea extract restored the level of antioxidant enzymes such as, superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH), and membrane bound enzymes like Na Na+K+ ATPase, Ca Ca2+ 2+ ATPase and Mg Mg2+ 2+ ATPase and decreased lipid peroxidation (MDA) in kidney and in testes of animals which were altered after chronic treatment with cisplatin. Thus it can be concluded that green tea extract possesses antioxidant activity and by virtue of this action it can protect the kidney and testes from cisplatin induced oxidative damage

Evaluación de la actividad scavenger frente a los radicales superóxido e hidroxilo por parte de algunos compuestos obtenidos de plantas medicinales colombianas / Scavanger activity to superoxide, peroxida and hydroxil radicals of several compounds obtained from Colombian medicinal plants

Se realizó un estudio para evaluar la posible actividad scavenger de 6 compuestos provenientes de plantas medicinales colombianas frente a los radicales superóxido, peroxilo e hidroxilo, mediante el uso de técnicas generadoras y atrapadoras de especies de oxígeno reactivas. Se comprobó la actividad antirradicalaria de la umbeliferona y la hesperidina, la mejor captación de radical peroxilo por khellina, escopolina y umbeliferona. La arbutina y el pinitol mostraron los mejores resultados frente al radical hidroxilo. Cinco de los seis compuestos mostraron resultados promisorios frente al radical superóxido