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1.
Plant Physiol Biochem ; 150: 109-120, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32135476

RESUMO

We investigated vanillic acid-induced salt tolerance in tomato by exploring the plant defense systems. Ten-d-old tomato (Solanum lycopersicum L. cv. Pusa Ruby) seedlings were treated with salt (NaCl; 150 mM) and vanillic acid (VA; 40 and 50 µM) separately and in combination with salt. Salinity restricted seedlings growth, biomass accumulation, chlorophyll and carotenoid contents. Salt-induced osmotic stress was indicated by lower leaf relative water content (RWC) and elevated proline (Pro) content, where higher Na+/K+ ratio indicated the ionic toxicity. Tomato seedlings went through oxidative damage due to acute reactive oxygen species (ROS) production and lipoxygenase (LOX) activity and confirmed by higher lipid peroxidation and membrane damage under salinity. Conversely, exogenous VA reduced osmotic and ionic toxicity in stressed-seedlings by enhancing the RWC and Pro level, and lowering Na+/K+ ratio, respectively. Exogenous VA up-regulated the components of antioxidant defense system in salt-treated seedlings resulted in the reduction of ROS production, LOX activity and membrane damage in stressed-seedlings. Additionally, VA application caused the reduction of toxic methylglyoxal accumulation under salt stress through the enhancement of glyoxalase system. Thus, VA-induced alleviation of osmotic, ionic and oxidative stresses leading to improve plant growth and chlorophyll synthesis in stressed-seedlings. So, VA significantly improves salinity tolerance and plant growth performance by involving the actions of plant antioxidant defense and glyoxalase systems.

2.
Sci Rep ; 9(1): 20026, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882854

RESUMO

The main objective of this experiment was to determine the effects of yogurt supplementation on fat deposition, oxidative stress, inflammation and fibrosis in the liver of rats with high-fat (HF) diet-induced obesity. Male Wistar rats were used in this study and were separated into the following four different groups: the control, control + yogurt, high fat and high fat+ yogurt groups. The high fat groups received a HF diet for eight weeks. A 5% yogurt (w/w) supplement was also provided to rats fed the HF diet. Yogurt supplementation prevented glucose intolerance and normalized liver-specific enzyme activities in the HF diet-fed rats. Yogurt supplementation also significantly reduced the levels of oxidative stress markers in the plasma and liver of HF diet-fed rats. Moreover, inflammatory cell infiltration, collagen deposition and fibrosis in the liver of HF diet-fed rats were also prevented by yogurt supplementation. Furthermore, yogurt supplementation normalized the intestinal lining and brush border in HF diet-fed rats. This study suggests that yogurt supplementation potentially represents an alternative therapy for the prevention of metabolic syndrome in HF diet-fed rats.

3.
Antioxidants (Basel) ; 8(9)2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505852

RESUMO

Reactive oxygen species (ROS) generation is a usual phenomenon in a plant both under a normal and stressed condition. However, under unfavorable or adverse conditions, ROS production exceeds the capacity of the antioxidant defense system. Both non-enzymatic and enzymatic components of the antioxidant defense system either detoxify or scavenge ROS and mitigate their deleterious effects. The Ascorbate-Glutathione (AsA-GSH) pathway, also known as Asada-Halliwell pathway comprises of AsA, GSH, and four enzymes viz. ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, and glutathione reductase, play a vital role in detoxifying ROS. Apart from ROS detoxification, they also interact with other defense systems in plants and protect the plants from various abiotic stress-induced damages. Several plant studies revealed that the upregulation or overexpression of AsA-GSH pathway enzymes and the enhancement of the AsA and GSH levels conferred plants better tolerance to abiotic stresses by reducing the ROS. In this review, we summarize the recent progress of the research on AsA-GSH pathway in terms of oxidative stress tolerance in plants. We also focus on the defense mechanisms as well as molecular interactions.

4.
Antioxidants (Basel) ; 8(9)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31480540

RESUMO

Salinity toxicity and the post-stress restorative process were examined to identify the salt tolerance mechanism in tomato, with a focus on the antioxidant defense and glyoxalase systems. Hydroponically grown 15 day-old tomato plants (Solanum lycopersicum L. cv. Pusa Ruby) were treated with 150 and 250 mM NaCl for 4 days and subsequently grown in nutrient solution for a further 2 days to observe the post-stress responses. Under saline conditions, plants showed osmotic stress responses that included low leaf relative water content and high proline content. Salinity induced oxidative stress by the over-accumulation of reactive oxygen species (H2O2 and O2•-) and methylglyoxal. Salinity also impaired the non-enzymatic and enzymatic components of the antioxidant defense system. On the other hand, excessive Na+ uptake induced ionic stress which resulted in a lower content of other minerals (K+, Ca2+, and Mg2+), and a reduction in photosynthetic pigment synthesis and plant growth. After 2 days in the normal nutrient solution, the plants showed improvements in antioxidant and glyoxalase system activities, followed by improvements in plant growth, water balance, and chlorophyll synthesis. The antioxidant and glyoxalase systems worked in concert to scavenge toxic reactive oxygen species (ROS), thereby reducing lipid peroxidation and membrane damage. Taken together, these findings indicate that tomato plants can tolerate salinity and show rapid post-stress recovery by enhancement of their antioxidant defense and glyoxalase systems.

5.
Plants (Basel) ; 8(7)2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31261970

RESUMO

The present study was designed to investigate the duration-dependent changes in the biochemical attributes of sesame in response to waterlogging stress. Sesame plants (Sesamum indicum L. cv. BARI Til-4) were subjected to waterlogging for 2, 4, 6, and 8 days during the vegetative stage and data were measured following waterlogging treatment. The present study proves that waterlogging causes severe damage to different attributes of the sesame plant. The plants showed an increasing trend in lipid peroxidation as well as hydrogen peroxide (H2O2) and methylglyoxal contents that corresponded to increased stress duration. A prolonged period of waterlogging decreased leaf relative water content and proline content. Photosynthetic pigments, like chlorophyll (chl) a, b, and chl (a+b) and carotenoid contents, also decreased over time in stressed plants. Glutathione (GSH) and oxidized glutathione (GSSG) contents increased under waterlogging, while the GSH/GSSG ratio and ascorbate content decreased, indicating the disruption of redox balance in the cell. Ascorbate peroxidase, monodehydroascorbate reductase, and glutathione peroxidase activity increased under waterlogging, while dehydroascorbate reductase, glutathione reductase, and catalase activity mostly decreased. Waterlogging modulated the glyoxalase system mostly by enhancing glyoxalase II activity, with a slight increase in glyoxalase I activity. The present study also demonstrates the induction of oxidative stress via waterlogging in sesame plants and that stress levels increase with increased waterlogging duration.

6.
Int J Mol Sci ; 20(13)2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31261998

RESUMO

Polyamines (PAs) are found in all living organisms and serve many vital physiological processes. In plants, PAs are ubiquitous in plant growth, physiology, reproduction, and yield. In the last decades, PAs have been studied widely for exploring their function in conferring abiotic stresses (salt, drought, and metal/metalloid toxicity) tolerance. The role of PAs in enhancing antioxidant defense mechanism and subsequent oxidative stress tolerance in plants is well-evident. However, the enzymatic regulation in PAs biosynthesis and metabolism is still under research and widely variable under various stresses and plant types. Recently, exogenous use of PAs, such as putrescine, spermidine, and spermine, was found to play a vital role in enhancing stress tolerance traits in plants. Polyamines also interact with other molecules like phytohormones, nitric oxides, trace elements, and other signaling molecules to providing coordinating actions towards stress tolerance. Due to the rapid industrialization metal/metalloid(s) contamination in the soil and subsequent uptake and toxicity in plants causes the most significant yield loss in cultivated plants, which also hamper food security. Finding the ways in enhancing tolerance and remediation mechanism is one of the critical tasks for plant biologists. In this review, we will focus the recent update on the roles of PAs in conferring metal/metalloid(s) tolerance in plants.


Assuntos
Metaloides/toxicidade , Metais/toxicidade , Plantas/metabolismo , Poliaminas/metabolismo , Estresse Fisiológico , Poluição Ambiental , Regulação da Expressão Gênica de Plantas , Metaloides/farmacocinética , Metais/farmacocinética , Plantas/efeitos dos fármacos , Plantas/genética
7.
Pediatr Infect Dis J ; 38(4): 344-350, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30882722

RESUMO

BACKGROUND: The contribution of respiratory viruses to childhood pneumonia in tropical low- and middle-income countries is poorly understood. We used population-based respiratory illness surveillance in children 5 years of age or younger in Dhaka, Bangladesh, to characterize these illnesses. METHODS: We conducted weekly home visits to children who were referred to clinic for fever or respiratory symptoms. Standardized clinical data were collected. Nasopharyngeal washes were collected for one fifth of children diagnosed with a febrile or respiratory syndrome, with virus isolation testing for influenza and reverse transcription polymerase chain reaction testing for other viruses. Pneumonia was defined as age-specific tachypnea and crepitations on chest auscultation by study physicians. RESULTS: From April 2004 to February 2008, 17,584 children were followed for 17,644 child-years; 6335 children had 12,499 clinic visits with eligible illnesses, including 6345 pneumonia episodes (incidence of 36 episodes/100 child-years). Annual incidence of pneumonia/100 child-years ranged from 88.3 for children 0-6 months of age to 13.1 for those 36-60 months of age. Of 1248 pneumonia visits with laboratory testing, 803 (64%) had detection of viral pathogens, including 274 respiratory syncytial virus (22% of pneumonia visits with laboratory testing; incidence 7.9/100 child-years), 244 adenovirus (19%; 7.0/100 child-years), 198 human metapneumovirus (16%; 5.7/100 child-years), 174 parainfluenza (14.0%; 5.0/100 child-years), and 81 influenza (6.5%; 2.3/100 child years). CONCLUSIONS: Viral pathogens contribute to a majority of childhood pneumonia episodes in Bangladesh, a setting with high pneumonia rates, especially in children 2 years of age or younger. Developing effective prevention strategies targeting these children is a high priority. Given less sensitive laboratory method used for influenza detection, influenza rates may be underestimated.

8.
Artigo em Inglês | MEDLINE | ID: mdl-30854003

RESUMO

Psidium guajava leaf is reported to contain many bioactive polyphenols which play an important role in the prevention and treatment of various diseases. Our investigation aimed to study the effect of Psidium guajava leaf powder supplementation on obesity and liver status by using experimental rats. To study the effects of guava leaf supplementation in high fat diet induced obesity, rats were randomly divided into four experimental groups (n=7), control (group I), control + guava leaf (group II), HCHF (group III), and HCHF + guava leaf (group IV). At the end of the experimental period (56 days), glucose intolerance, liver enzymes activities, antioxidant enzymes activities, and lipid and cholesterol profiles were evaluated. Our results revealed that guava leaf powder supplementation showed a significant reduction in fat deposition in obese rats. Moreover, liver enzyme functions were increased in high fat diet fed rats compared to the control rats significantly which were further ameliorated by guava leaf powder supplementation in high fat diet fed rats. High fat diet feeding also decreased the antioxidant enzyme functions and increased the lipid peroxidation products compared to the control rats. Guava leaf powder supplementation in high fat diet fed rats reduced the oxidative stress markers and reestablished antioxidant enzyme system in experimental animals. Guava leaf powder supplementation in high fat diet fed rats also showed a relative decrease in inflammatory cells infiltration and collagen deposition in the liver compared to the high fat diet fed rats. The present study suggests that the supplementation of guava leaf powder prevents obesity, improves glucose intolerance, and decreases inflammation and oxidative stress in liver of high carbohydrate high fat diet fed rats.

9.
Ecotoxicology ; 28(3): 261-276, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30761430

RESUMO

Nickel (Ni), an essential nutrient of plant but very toxic to plant at supra-optimal concentration that causes inhibition of seed germination emergence and growth of plants as a consequence of physiological disorders. Hence, the present study investigates the possible mechanisms of Ni tolerance in rice seedlings by exogenous application of silicon (Si). Thirteen-day-old hydroponically grown rice (Oryza sativa L. cv. BRRI dhan54) were treated with Ni (NiSO4.7H2O, 0.25 and 0.5 mM) sole or in combination with 0.50 mM Na2SiO3 for a period of 3 days to investigate the effect of Si supply for revoking the Ni stress. Nickel toxicity gave rise to reactive oxygen species (ROS) and cytotoxic methylglyoxal (MG), accordingly, initiated oxidative stress in rice leaves, and accelerated peroxidation of lipids and consequent damage to membranes. Reduced growth, biomass accumulation, chlorophyll (chl) content, and water balance under Ni-stress were also found. However, free proline (Pro) content increased in Ni-exposed plants. In contrast, the Ni-stressed seedlings fed with supplemental Si reclaimed the seedlings from chlorosis, water retrenchment, growth inhibition, and oxidative stress. Silicon up-regulated most of the antioxidant defense components as well as glyoxalase systems, which helped to improve ROS scavenging and MG detoxification. Hence, these results suggest that the exogenous Si application can improve rice seedlings' tolerance to Ni-toxicity.


Assuntos
Antioxidantes/metabolismo , Níquel/farmacologia , Oryza/efeitos dos fármacos , Aldeído Pirúvico/metabolismo , Plântula/efeitos dos fármacos , Silício/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Níquel/metabolismo , Oryza/fisiologia , Estresse Oxidativo , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico
10.
Physiol Mol Biol Plants ; 24(6): 993-1004, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30425418

RESUMO

Nitric oxide (NO) is an important plant signaling molecule that has a vital role in abiotic stress tolerance. In the present study, we assessed drought-induced (15 and 30% PEG, polyethylene glycol) damage in wheat (Triticum aestivum L. cv. Prodip) seedlings and mitigation by the synergistic effect of exogenous Arg (0.5 mM l-Arginine) and an NO donor (0.5 mM sodium nitroprusside, SNP). Drought stress sharply decreased the leaf relative water content (RWC) but markedly increased the proline (Pro) content in wheat seedlings. Drought stress caused overproduction of reactive oxygen species (ROS) and methylglyoxal (MG) due to the inefficiency of antioxidant enzymes, the glyoxalase system, and the ascorbate-glutathione pool. However, supplementation with the NO donor and Arg enhanced the antioxidant defense system (both non-enzymatic and enzymatic components) in drought-stressed seedlings. Application of the NO donor and Arg also enhanced the glyoxalase system and reduced the MG content by increasing the activities of the glyoxalase system enzymes (Gly I and Gly II), which restored the leaf RWC and further increased the Pro content under drought stress conditions. Exogenous NO donor and Arg application enhanced the endogenous NO content, which positively regulated the antioxidant system and reduced ROS production. Thus, the present study reveals the crucial roles of Arg and NO in enhancing drought stress tolerance in wheat seedlings by upgrading their water status and reducing oxidative stress and MG toxicity.

11.
Ecotoxicol Environ Saf ; 147: 990-1001, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29976011

RESUMO

Cadmium (Cd) is a serious environmental threat because it accumulates in plants from soil and is subsequently transported into the food cycle. Increased Cd uptake in plants disrupts plant metabolism and hampers crop growth and development. Therefore, remediation of Cd from soil and enhancing plant tolerance to metal toxicity is vital. In the present study, we investigated the function of different doses of citric acid (CA) on Cd toxicity in terms of metal accumulation and stress tolerance in mustard (Brassica juncea L.). Brassica juncea seedlings (12-day-old) were treated with Cd (0.5mMCd and 1.0mM CdCl2) alone and in combination with CA (0.5mM and 1.0mM) in a semi-hydroponic medium for three days. Cadmium accumulation in the roots and shoots of the mustard seedlings increased in a dose-dependent manner and was higher in the roots. Increasing the Cd concentration led to reduced growth, biomass, water status, and chlorophyll (chl) content resulting from increased oxidative damage (elevated malondialdehyde, MDA content; hydrogen peroxide, H2O2 level; superoxide, O2•- generation; lipoxygenase, LOX activity; and methylglyoxal, MG content) and downregulating of the major enzymes of the antioxidant defense and glyoxalase systems. Under Cd stress, both doses of CA improved the growth of the plants by enhancing leaf relative water content (RWC) and chl content; reducing oxidative damage; enhancing the pool of ascorbate (AsA) and glutathione (GSH) and the activities of the antioxidant enzymes (ascorbate peroxidase, APX; monodehydroascorbate reductase, MDHAR; dehydroascorbate reductase, DHAR; glutathione reductase, GR; glutathione peroxidase, GPX; superoxide dismutase, SOD; catalase, CAT); improving the performance of the glyoxalase system (glyoxalase I, Gly I and glyoxalase II, Gly II activity); and increasing the phytochelatin (PC) content. Exogenous CA also increased the root and shoot Cd content and Cd translocation from the roots to the shoots in a dose-dependent manner. Our findings suggest that CA plays a dual role in mustard seedlings by increasing phytoremediation and enhancing stress tolerance through upregulating the antioxidant defense and glyoxalase systems.


Assuntos
Antioxidantes/metabolismo , Cádmio/metabolismo , Lactoilglutationa Liase/metabolismo , Mostardeira/metabolismo , Ascorbato Peroxidases/metabolismo , Ácido Ascórbico/metabolismo , Biodegradação Ambiental , Cádmio/toxicidade , Catalase/metabolismo , Ácido Cítrico/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Mostardeira/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Oxirredutases , Fitoquelatinas/metabolismo , Aldeído Pirúvico/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Superóxido Dismutase/metabolismo , Tioléster Hidrolases/metabolismo
12.
Biomed Pharmacother ; 103: 1154-1162, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29715759

RESUMO

Red spinach (Amaranthus tricolor) has been reported to possess many benefits and medicinal properties and used as a part of traditional medicine in Ayurveda and Siddha. The aim of the study was to investigate the effects of Amaranthus tricolor on isoproterenol-induced oxidative stress, fibrosis, and myocardial damage in ovariectomized rats. Ovariectomy surgery was conducted to remove both ovaries from the rats. After recovery, rats were administered with ISO subcutaneously (50 mg/kg) twice a week and were treated with ethanolic extracts of A. tricolor. This investigation showed that the level of oxidative stress markers was significantly increased while the superoxide dismutase (SOD) activity decreased in ISO administered ovariectomized rats. A. tricolor extract and atenolol treatment prevented the rise of malondialdehyde, nitric oxide and advanced protein oxidation product. Moreover, elevated activities of AST, ALT, and CK-MB enzymes were also lowered by both atenolol and A. tricolor treatment. Increased uric acid and creatinine levels were also normalized by atenolol, and A. Tricolor treatment in ISO administered ovariectomized rats. ISO-induced ovariectomized rats also showed massive inflammatory cell infiltration, fibrosis and iron deposition in heart compared to sham rats. Atenolol and A. tricolor treatment prevented the inflammatory cells infiltration, fibrosis, and iron deposition. These results suggest that A. tricolor treatment may protect against ISO administered myocardial infarction in ovariectomized rats probably by preventing inflammation, oxidative stress, and fibrosis. Further research is warranted to examine molecular mechanism of cardioprotective effect of A. tricolor.


Assuntos
Amaranthus/química , Cardiotônicos/uso terapêutico , Infarto do Miocárdio/prevenção & controle , Miocárdio/patologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Animais , Cardiotônicos/isolamento & purificação , Modelos Animais de Doenças , Feminino , Isoproterenol , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Ovariectomia , Extratos Vegetais/isolamento & purificação , Ratos Wistar
13.
Phytopathology ; 108(9): 1046-1055, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29658842

RESUMO

Potato cultivars vary in their tolerance to common scab; however, how they affect common scab-causing Streptomyces spp. populations over time is poorly understood. This study investigated the effects of potato cultivar on pathogenic Streptomyces spp. abundance, measured using quantitative PCR, in three spatial locations in a common scab-infested field: (i) soil close to the plant (SCP); (ii) rhizosphere soil (RS); and (iii) geocaulosphere soil (GS). Two tolerant (Gold Rush, Hindenburg) and two susceptible cultivars (Green Mountain, Agria) were tested. The abundance of pathogenic Streptomyces spp. significantly increased in late August compared with other dates in RS of susceptible cultivars in both years. Abundance of pathogenic Streptomyces spp., when averaged over locations and time, was significantly greater in susceptible cultivars compared with tolerant cultivars in 2014. Principal coordinates analysis showed that SCP and RS soil properties (pH, organic carbon, and nitrogen concentrations) explained 68 and 76% of total variation in Streptomyces spp. abundance among cultivars in 2013, respectively, suggesting that cultivars influenced common scab pathogen growth conditions. The results suggested that the genetic background of potato cultivars influenced the abundance of pathogenic Streptomyces spp., with five to six times more abundant Streptomyces spp. in RS of susceptible cultivars compared with tolerant cultivars, which would result in substantially more inoculum left in the field after harvest.


Assuntos
Doenças das Plantas/microbiologia , Microbiologia do Solo , Solanum tuberosum/microbiologia , Streptomyces/isolamento & purificação , Tubérculos/genética , Tubérculos/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Rizosfera , Solanum tuberosum/genética , Streptomyces/genética
14.
Plant Physiol Biochem ; 126: 173-186, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29525441

RESUMO

To investigate the physiological and biochemical mechanisms of nitric oxide (NO)-induced paraquat (PQ) tolerance in plants, we pretreated a set of 10-day-old Brassica napus seedlings with 500 µM sodium nitroprusside (SNP - a NO donor) for 24 h. Then, three doses of PQ (62.5, 125 and 250 µM) were applied separately, as well as to SNP-pretreated seedlings, and the seedlings were allowed to grow for an additional 48 h. The seedlings treated with PQ showed clear, dose-dependent signs of oxidative stress, with elevated levels of lipid peroxidation (MDA, malondialdehyde), H2O2 and O2- generation, and lipoxygenase (LOX) activity. Paraquat treatment disrupted pools of water-soluble antioxidants (ascorbate-AsA and reduced glutathione-GSH). Paraquat had different effects on the activities of antioxidant enzymes. The activities of glutathione reductase (GR) and catalase (CAT) decreased after PQ treatment in a dose-dependent manner, while the activities of ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR) and glyoxalase (Gly I and Gly II) decreased only with high doses of PQ (125 and 250 µM). By contrast, the activities of monodehydroascorbate reductase (MDHAR), glutathione S-transferase (GST) and glutathione peroxidase (GPX) increased after PQ treatment. A higher dose of PQ reduced chlorophyll and leaf water content but increased the methylglyoxal (MG) and proline (Pro) content. Compared to PQ alone, PQ supplemented with exogenous NO reduced LOX activity, the AsA-GSH pool, and the activities of APX, DHAR, GR, GPX, Gly I and Gly II. These effects helped to reduce oxidative stress and MG toxicity and were accompanied by reduced chlorosis and increased relative water content. Given these results, exogenous NO was found to be a key player in the mitigation of PQ toxicity in plants.


Assuntos
Antioxidantes/metabolismo , Brassica napus/metabolismo , Liases de Carbono-Enxofre/biossíntese , Óxido Nítrico/farmacologia , Oxirredutases/biossíntese , Paraquat/toxicidade , Proteínas de Plantas/biossíntese , Plântula/metabolismo , Folhas de Planta/metabolismo
15.
Mol Pharm ; 15(5): 1755-1765, 2018 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-29528655

RESUMO

We investigated the feasibility of a combination therapy comprising fasudil, a Rho-kinase inhibitor, and DETA NONOate (diethylenetriamine NONOate, DN), a long-acting nitric oxide donor, both loaded in liposomes modified with a homing peptide, CAR (CARSKNKDC), in the treatment of pulmonary arterial hypertension (PAH). We first prepared and characterized unmodified and CAR-modified liposomes of fasudil and DN. Using individual drugs alone or a mixture of fasudil and DN as controls, we studied the efficacy of the two liposomal preparations in reducing mean pulmonary arterial pressure (mPAP) in monocrotaline (MCT) and SUGEN-hypoxia-induced PAH rats. We also conducted morphometric studies (degree of muscularization, arterial medial wall thickness, and collagen deposition) after treating the PAH rats with test and control formulations. When the rats were treated acutely and chronically, the reduction in mPAP was more pronounced in the liposomal formulation-treated rats than in plain drug-treated rats. CAR-modified liposomes were more selective in reducing mPAP than unmodified liposomes of the drugs. Both drugs, formulated in CAR-modified liposomes, reduced the degree of muscularization, medial arterial wall thickness, and collagen deposition more than the combination of plain drugs did. As seen with the in vivo data, CAR-modified liposomes of fasudil or DN increased the levels of the vasodilatory signaling molecule, cGMP, in the smooth muscle cells of PAH-afflicted human pulmonary arteries. Overall, fasudil and DN, formulated in liposomes, could be used as a combination therapy for a better management of PAH.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Hipertensão Pulmonar/tratamento farmacológico , Lipossomos/química , Pulmão/efeitos dos fármacos , Doadores de Óxido Nítrico/farmacologia , Peptídeos/farmacologia , Poliaminas/farmacologia , Artéria Pulmonar/efeitos dos fármacos , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Animais , Química Farmacêutica/métodos , Progressão da Doença , Hipertensão Pulmonar/metabolismo , Pulmão/metabolismo , Masculino , Monocrotalina/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Artéria Pulmonar/metabolismo , Ratos , Ratos Sprague-Dawley , Vasodilatadores/farmacologia , Quinases Associadas a rho/metabolismo
16.
Immunotherapy ; 10(4): 283-298, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29421982

RESUMO

Prostate cancer (PC) is a common malignancy among elderly males and is noncurable once it becomes metastatic. In recent years, a number of antigen-delivery systems have emerged as viable and promising immunotherapeutic agents against PC. The approval of sipuleucel-T by the US FDA for the treatment of males with asymptomatic or minimally symptomatic castrate resistant PC was a landmark in cancer immunotherapy, making this the first approved immunotherapeutic. A number of vaccines are under clinical investigation, each having its own set of advantages and disadvantages. Here, we discuss the basic technologies underlying these different delivery modes, we discuss the completed and current human clinical trials, as well as the use of vaccines in combination with immune checkpoint inhibitors.


Assuntos
Imunoterapia/métodos , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/terapia , Humanos , Masculino , Próstata/imunologia , Neoplasias da Próstata/secundário
17.
New Phytol ; 218(2): 646-660, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29464725

RESUMO

Gibberellin (GA) regulates various plant growth and developmental processes, but its role in pathogen attack, and especially nematode-plant interactions, still remains to be elucidated. An in-depth characterization of the role of GA in nematode infection was conducted using mutant lines of rice, chemical inhibitors, and phytohormone measurements. Our results showed that GA influences rice-Meloidogyne graminicola interactions in a concentration-dependent manner. Foliar spray of plants with a low concentration of gibberellic acid enhanced nematode infection. Biosynthetic and signaling mutants confirmed the importance of gibberellin for rice susceptibility to M. graminicola infection. Our study also demonstrates that GA signaling suppresses jasmonate (JA)-mediated defense against M. graminicola, and likewise the JA-induced defense against M. graminicola requires SLENDER RICE1 (SLR1)-mediated repression of the GA pathway. In contrast to observations from other plant-pathogen interactions, GA plays a dominant role over JA in determining susceptibility to M. graminicola in rice. This GA-induced nematode susceptibility was largely independent of auxin biosynthesis, but relied on auxin transport. In conclusion, we showed that GA-JA antagonistic crosstalk is at the forefront of the interaction between rice and M. graminicola, and SLR1 plays a central role in the JA-mediated defense response in rice against this nematode.


Assuntos
Ciclopentanos/farmacologia , Giberelinas/farmacologia , Oryza/imunologia , Oryza/parasitologia , Oxilipinas/farmacologia , Tylenchoidea/fisiologia , Animais , Transporte Biológico/efeitos dos fármacos , Suscetibilidade a Doenças , Ácidos Indolacéticos/metabolismo , Modelos Biológicos , Oryza/efeitos dos fármacos , Doenças das Plantas/imunologia , Doenças das Plantas/parasitologia , Reguladores de Crescimento de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Tumores de Planta/parasitologia , Tylenchoidea/efeitos dos fármacos
18.
Environ Sci Pollut Res Int ; 25(8): 7954-7967, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29302908

RESUMO

The Madhabdi municipality in the Narsingdi district of Bangladesh is a well-known area for textile, handloom weaving, and dyeing industries. These textile industries produce a considerable amount of effluents, sewage sludge, and solid waste materials every day that they directly discharge into surrounding water bodies and agricultural fields. This disposal poses a serious threat to the overall epidemic and socio-economic pattern of the locality. This research entailed the collection of 34 handloom-dyeing effluent samples from different handloom-dyeing industries of Madhabdi, which were then analyzed to determine the contents of the heavy metals iron (Fe), zinc (Zn), copper (Cu), chromium (Cr), manganese (Mn), lead (Pb), and cadmium (Cd). Average concentrations of Fe, Cr, Cu, Pb, Mn, and Zn were 3.81, 1.35, 1.70, 0.17, 0.75, and 0.73 mg L-1, respectively, whereas Cd content was below the detectable limit of the atomic adsorption spectrophotometer. The concentrations of Fe, Cr, Cu, Pb, and Mn exceed the industrial effluent discharge standards (IEDS) for inland surface water and irrigation water guideline values. A biosorption experiment of the heavy metals (Fe, Cr, Cu, Mn, and Zn) was conducted without controlling for any experimental parameters (e.g., pH, temperature, or other compounds present in the effluent samples) by using four agricultural wastes or byproducts, namely rice husk, sawdust, lemon peel, and eggshell. Twenty grams of each biosorbent was added to 1 L of effluent samples and stored for 7 days. The biosorption capacity of each biosorbent is ranked as follows: eggshell, sawdust, rice husk, and lemon peel. Furthermore, the biosorption affinity of each metal ion was found in the following order: Cu and Cr (both had similar biosorption affinity), Zn, Fe, Mn. The effluents should not be discharged before treatment, and efficient treatment of effluents is possible with eggshell powder or sawdust at a rate of 20 g of biosorbent per liter of effluents.


Assuntos
Corantes/química , Metais Pesados/análise , Metais Pesados/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Adsorção , Agricultura , Bangladesh , Biodegradação Ambiental , Eliminação de Resíduos Líquidos/normas
19.
BMC Complement Altern Med ; 18(1): 35, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29378554

RESUMO

BACKGROUND: It has been observed that the various part of Baccaurea ramiflora plant is used in rheumatoid arthritis, cellulitis, abscesses, constipation and injuries. This plant also has anticholinergic, hypolipidemic, hypoglycemic, antiviral, antioxidant, diuretic and cytotoxic activities. The present studyaimed to assess the cytotoxic, analgesic, anti-inflammatory, CNS depressant and antidiarrheal activities of methanol extract of Baccaurea ramiflora pulp and seeds in mice model. METHODS: The cytotoxic activity was determined by brine shrimp lethality bioassay; anti-nociceptive activity was determined by acetic acid-induced writhing, formalin- induced licking and biting, and tail immersion methods. The anti-inflammatory, CNS depressant and anti-diarrheal activities were assessed by carrageenan-induced hind paw edema, the open field and hole cross tests, and castor oil-induced diarrheal methods, respectively. The data were analyzed by one way ANOVA (analysis of variance) followed by Dunnett's test. RESULTS: In brine shrimp lethality bioassay, the LC50 values of the methanol extracts of Baccaurea ramiflora pulp and seed were 40 µg/mL and 10 µg/mL, respectively. Our investigation showed that Baccaurea ramiflora pulp and seed extracts (200 mg/kg) inhibited acetic acid induced pain 67.51 and 66.08%, respectively (p < 0.05) that was strongly comparable with that of Ibuprofen (72%) (p < 0.05). The Baccaurea ramiflora pulp and seed extracts (200 mg/kg) significantly (p < 0.05) reduced 58.5 and 53.4 in early and 80.8%, 76.61% in late phase of formalin-induced licking and biting. At 60 and 90 min pulp and seed extracts (200 mg/kg) inhibited nociception of thermal stimulus 50.16 and 62.4%, respectively (p < 0.05) which was comparable with the standard (morphine, 75.9% inhibition). The pulp and seed extracts (200 mg/kg) significantly (p < 0.05) reduced inflammation (42.00 and 55.22%, respectively) in carrageenan-induced hind paw edema and defecations (59.7 and 63.03%, respectively) in castor oil induced diarrhea. Both the extracts showed high sedative activity at 30, 60, 90, and 120 min. CONCLUSION: Our investigation demonstrated significant cytotoxic, analgesic, anti-inflammatory, CNS depressant and antidiarrheal activities of methanol extract of Baccaurea ramiflora pulp and seeds (200 mg/kg).


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Antidiarreicos/farmacologia , Depressores do Sistema Nervoso Central/farmacologia , Extratos Vegetais/farmacologia , Analgésicos/química , Animais , Anti-Inflamatórios/química , Antidiarreicos/química , Artemia/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Depressores do Sistema Nervoso Central/química , Diarreia , Masculino , Camundongos , Manejo da Dor , Extratos Vegetais/química
20.
Vaccine ; 35(50): 6967-6976, 2017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-29100706

RESUMO

BACKGROUND: Few trials have evaluated influenza vaccine efficacy (VE) in young children, a group particularly vulnerable to influenza complications. We aimed to estimate VE against influenza in children aged <2 years in Bangladesh; a subtropical setting, where influenza circulation can be irregular. METHODS: Children aged 6-23 months were enrolled 1:1 in a parallel, double-blind, randomized controlled trial of trivalent inactivated influenza vaccine (IIV3) versus inactivated polio vaccine (IPV); conducted August 2010-March 2014 in Dhaka, Bangladesh. Children received two pediatric doses of vaccine, one month apart, and were followed for one year for febrile and respiratory illness. Field assistants conducted weekly home-based, active surveillance and ill children were referred to the study clinic for clinical evaluation and nasopharyngeal wash specimen collection. Analysis included all children who received a first vaccine dose and compared yearly incidence of reverse transcription polymerase chain reaction (RT-PCR)-confirmed influenza between trial arms. The VE was estimated as 1-(rate ratio of illness) × 100%, using unadjusted Poisson regression. The trial was registered with ClinicalTrials.gov, number NCT01319955. RESULTS: Across four vaccination rounds, 4081 children were enrolled and randomized, contributing 2576 child-years of observation to the IIV3 arm and 2593 child-years to the IPV arm. Influenza incidence was 10 episodes/100 child-years in the IIV3 arm and 15 episodes/100 child-years in the IPV arm. Overall, the VE was 31% (95% confidence interval 18, 42%) against any RT-PCR-confirmed influenza. The VE varied by season, but was similar by influenza type/subtype and participant age and sex. CONCLUSIONS: Vaccination of young children with IIV3 provided a significant reduction in laboratory-confirmed influenza; however, exploration of additional influenza vaccine strategies, such as adjuvanted vaccines or standard adult vaccine doses, is warranted to find more effective influenza vaccines for young children in low-income countries.


Assuntos
Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Bangladesh , Método Duplo-Cego , Feminino , Humanos , Lactente , Vacinas contra Influenza/administração & dosagem , Masculino , Resultado do Tratamento
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