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1.
J Food Biochem ; 46(10): e14262, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35796388

RESUMEN

SARS-CoV-2 has been responsible for causing 6,218,308 deaths globally till date and has garnered worldwide attention. The lack of effective preventive and therapeutic drugs against SARS-CoV-2 has further worsened the scenario and has bolstered research in the area. The N-terminal and C-terminal RNA binding domains (NTD and CTD) of SARS-CoV-2 nucleocapsid protein represent attractive therapeutic drug targets. Naturally occurring compounds are an excellent source of novel drug candidates due to their structural diversity and safety. Ten major bioactive compounds were identified in ethanolic extract (s) of Cinnamomum zeylanicum, Cinnamomum tamala, Origanum vulgare, and Petroselinum crispum using HPLC and their cytotoxic potential was determined against cancer and normal cell lines by MTT assay to ascertain their biological activity in vitro. To evaluate their antiviral potential, the binding efficacy to NTD and CTD of SARS-CoV-2 nucleocapsid protein was determined using in silico biology tools. In silico assessment of the phytocomponents revealed that most of the phytoconstituents displayed a druglike character with no predicted toxicity. Binding affinities were in the order apigenin > catechin > apiin toward SARS-CoV-2 nucleocapsid NTD. Toward nucleocapsid CTD, the affinity decreased as apigenin > cinnamic acid > catechin. Remdesivir displayed lesser affinity with NTD and CTD of SARS-CoV-2 nucleocapsid proteins than any of the studied phytoconstituents. Molecular dynamics (MD) simulation results revealed that throughout the 100 ns simulation, SARS-CoV-2 nucleocapsid protein NTD-apigenin complex displayed greater stability than SARS-CoV-2 nucleocapsid protein NTD-cinnamic acid complex. Hence, apigenin, catechin, apiin and cinnamic acid might prove as effective prophylactic and therapeutic candidates against SARS-CoV-2, if examined further in vitro and in vivo. PRACTICAL APPLICATIONS: Ten major bioactive compounds were identified in the extract(s) of four medicinally important plants viz. Cinnamomum zeylanicum, Cinnamomum tamala, Origanum vulgare and Petroselinum crispum using HPLC and their biological activity was also evaluated against cancer and normal cell lines. Interestingly, while all extract(s) wielded significant cytotoxicity against cancer cells, no significant toxicity was found against normal cells. The outcome of the results prompted evaluation of the antiviral potential of the ten bioactive compounds using in silico biology tools. The present study emphasizes on the application of computational approaches to understand the binding interaction and efficacy of the ten bioactive compounds from the above plants with SARS-CoV-2 nucleocapsid protein N-terminal and C-terminal RNA binding domains in preventing and/or treating COVID-19 using in silico tools. Druglikeness and toxicity profiles of the compounds were carried out to check the therapeutic application of the components. Additionally, molecular dynamics (MD) simulation was performed to check the stability of ligand-protein complexes. The results provided useful insights into the structural binding interaction(s) that can be exploited for the further development of potential antiviral agents targeting SARS-CoV-2 especially since no specific therapy is still available to combat the rapidly evolving virus and the existing treatment is more or less symptomatic which makes search for novel antiviral agents all the more necessary and crucial.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Catequina , Laurus , Origanum , Antivirales/química , Antivirales/farmacología , Apigenina , Cinamatos , Cinnamomum zeylanicum/metabolismo , Suplementos Dietéticos , Laurus/metabolismo , Ligandos , Petroselinum/metabolismo , SARS-CoV-2
3.
Br J Anaesth ; 127(1): 153-163, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34006377

RESUMEN

BACKGROUND: Nerve damage is consistently demonstrated after subepineural injection in animal studies, but not after purposeful injection in patients participating in clinical studies. There is a need to better visualise nerves in order to understand the structural changes that occur during subepineural injection. METHODS: We scanned the brachial plexuses of three anaesthetised pigs using micro-ultrasound imaging (55-22 MHz probe), inserted 21 gauge block needles into the radial, median, and axillary nerves, and injected two 0.5 ml boluses of saline into nerves at a rate of 12 ml min-1. Our objectives were to measure the area and diameter of nerves and fascicles, and to describe changes in nerve anatomy, comparing our findings with histology. RESULTS: Images were acquired at 42 sites across 18 nerves in three pigs and compared dimensions (geometric ratio; 95% confidence interval; P value). As expected, the nerve cross-sectional area was greater in the proximal brachial plexus compared with the mid-plexus (2.10; 1.07-4.11; P<0.001) and the distal plexus (2.64; 1.42-4.87; P<0.001). Nerve area expanded after 0.5 ml injection (2.13; 1.48-3.08; P<0.001). Using microultrasound, subepineural injection was characterised by nerve and fascicle rotation, uniform, or localised swelling and epineural rupture. Micro-ultrasound revealed a unique pattern suggestive of subperineural injection after a median nerve injection, and good face validity with histology. Histology showed epineural trauma and inflammation to the perineurium. CONCLUSION: We accurately identified fascicles and real-time structural changes to peripheral nerves using micro-ultrasound. This is the first study to visualise in vivo and in real-time the motion of nerves and fascicles in response to anaesthetic needle insertion and fluid injection.


Asunto(s)
Bloqueo del Plexo Braquial/métodos , Plexo Braquial/diagnóstico por imagen , Sistemas de Computación , Transductores , Ultrasonografía Intervencional/métodos , Adyuvantes Anestésicos/administración & dosificación , Anestésicos Disociativos/administración & dosificación , Animales , Plexo Braquial/efectos de los fármacos , Masculino , Nervios Periféricos/diagnóstico por imagen , Nervios Periféricos/efectos de los fármacos , Porcinos
4.
Reg Anesth Pain Med ; 46(6): 540-548, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33906953

RESUMEN

INTRODUCTION: Although administration of regional anesthesia nerve blocks has increased during the COVID-19 pandemic, training opportunities in regional anesthesia have reduced. Simulation training may enhance skills, but simulators must be accurate enough for trainees to engage in a realistic way-for example, detection of excessive injection pressure. The soft-embalmed Thiel cadaver is a life-like, durable simulator that is used for dedicated practice and mastery learning training in regional anesthesia. We hypothesized that injection opening pressure in perineural tissue, at epineurium and in subepineurium were similar to opening pressures measured in experimental animals, fresh frozen cadavers, glycol soft-fix cadavers and patients. METHODS: We systematically reviewed historical data, then conducted three validation studies delivering a 0.5 mL hydrolocation bolus of embalming fluid and recording injection pressure. First, we delivered the bolus at 12 mL/min at epimysium, perineural tissue, epineurium and in subepineurium at 48 peripheral nerve sites on three cadavers. Second, we delivered the bolus at using three infusion rates: 1 mL/min, 6 mL/min and 12 mL/min on epineurium at 70 peripheral nerve sites on five cadavers. Third, we repeated three injections (12 mL/min) at 24 epineural sites over the median and sciatic nerves of three cadavers. RESULTS: Mean (95%) injection pressure was greater at epineurium compared with subepineurium (geometric ratio 1.2 (95% CI: 0.9 to 1.6)), p=0.04, and perineural tissue (geometric ratio 5.1 (95% CI: 3.7 to 7.0)), p<0.0001. Mean (95%) injection pressure was greater at 12 mL/min compared with 1 mL/min (geometric ratio 1.6 (95% CI: 1.2 to 2.1), p=0.005). Pressure measurements were similar in study 3 (p>0.05 for all comparisons). DISCUSSION: We conclude that the soft-embalmed Thiel cadaver is a realistic simulator of injection opening pressure.


Asunto(s)
COVID-19 , Embalsamiento/normas , Simulación de Paciente , Animales , Cadáver , Humanos , Pandemias , Reproducibilidad de los Resultados , SARS-CoV-2
5.
J Ethnopharmacol ; 219: 110-116, 2018 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-29408310

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: India being a multicultural nation, every region of the country offers a distinct culinary flavor and taste. These flavors are attributed to spices and condiments which form the mainstay of Indian cuisine. Most of these spices and condiments are derived from various biodiversity hotspots in India and form the crux of India's multidiverse and multicultural cuisine. Apart from their varying aromas, flavors and tastes, these spices and condiments are known to possess several medicinal properties also. Most of these spices find considerable mention in Ayurveda, the indigenous system of medicine, as panaceas for several aliments. Cinnamomum zeylanicum (CZ), belonging to family Lauraceae and commonly known as cinnamon is one such spice known to have diverse medicinal properties since time immemorial. AIM OF THE STUDY: In the present study, apoptotic and anti-microbial activity of ethanolic extract of CZ was evaluated against human breast cancer cell line MDA-MB-231 and compared for its effect on normal kidney epithelial cell line Vero. MATERIALS AND METHODS: Ethanolic extract of tree bark of CZ was used to determine the cytotoxic effect on MDA-MB-231 using Trypan blue dye exclusion method and cytometry. The tested dose of the extract was 10-100 µg/mL. Antibacterial activity was determined using disc diffusion method against Staphylococcus aureus and Escherichia coli in the range 2-10 mg/mL. Apoptotic activity was determined using DNA fragmentation assay. RESULTS: Ethanolic extract of CZ was found to have an IC50 value of 25 µg/mL against MDA cell line. On the other hand, CZ extract did not have any significant effect on Vero cells even at 100 µg/mL (IC50 > 100 µg/mL). The ethanolic extract of CZ bark showed significant antibacterial activity against S. aureus at 10 mg/mL while no appreciable activity was detected against E. coli. DNA isolated from extract treated cancer cells showed a fragmentation pattern characteristic of apoptosis. However, no DNA fragmentation was observed in DNA isolated from extract treated Vero cells. CONCLUSION: Ethanolic bark extract of CZ could be potentially beneficial in treating breast cancer and may be of interest for future studies in developing integrative cancer therapy against proliferation, metastasis, and migration of breast cancer cells.


Asunto(s)
Antibacterianos/farmacología , Supervivencia Celular/efectos de los fármacos , Cinnamomum zeylanicum , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Línea Celular Tumoral , Supervivencia Celular/fisiología , Chlorocebus aethiops , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Etanol/farmacología , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología , Células Vero
6.
Taiwan J Ophthalmol ; 7(3): 138-142, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29034152

RESUMEN

PURPOSE: The present study was carried out to investigate the association of fatty acid-binding protein 2 (FABP2) and fat mass and obesity-associated (FTO) gene polymorphism with primary open-angle glaucoma (POAG) cases and controls. MATERIALS AND METHODS: This study includes 122 POAG cases and 112 controls. FABP2 and FTO gene polymorphisms in cases and controls were evaluated by polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: The mean ages were 49.88 ± 12.34 and 53.74 ± 11.87 years in POAG cases and control groups, respectively. The FABP2 gene AA, AT, TT genotype frequencies were 12.90%, 62.40%, 24.80% in POAG cases and 20.60%, 64.70%, 14.70% in healthy controls, respectively. The frequencies of A and T allele in POAG cases were 44.06% and 55.94% as compared to 52.94% and 47.06% in the controls. The FTO gene AA, AT, TT genotype frequencies were 2.00%, 79.20%, 18.80% in cases and 0%, 75.50%, 24.50% in healthy controls, respectively. The frequencies of A and T allele in POAG cases were 41.58% and 58.42% as compared to 37.75% and 62.25% in the controls. No significant difference in the frequencies of FABP2 and FTO genotype was found between POAG cases and controls. CONCLUSION: We could not identify the possible association of FABP2 and FTO gene polymorphism with POAG; however, further studies with larger sample size in different population are require to clarify the role of FABP2 and FTO genes in susceptibility to POAG.

7.
Oman J Ophthalmol ; 10(1): 21-25, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28298860

RESUMEN

BACKGROUND: Senile cataract is the most common type of cataract characterized by gradual progressive thickening of the lens of the eye. Previously, many studies investigated the association between genetic polymorphism and senile cataract. Angiotensin-converting enzyme (ACE) I/D polymorphism is the potential risk factor for many eye-related diseases such as retinopathy and glaucoma. CYP46A1 enzyme converts cholesterol to 24S-hydroxycholesterol; human lens' membranes contain the highest cholesterol content. Defects in enzymes of cholesterol metabolism can be associated with cataracts. Hence, the present study was carried out to investigate the association of ACE and CYP46A1 genes polymorphism with senile cataract cases and controls. MATERIALS AND METHODS: ACE (rs 4646994) and CYP46A1 (rs 754203) genes polymorphism in cases and controls were evaluated by polymerase chain reaction and restriction fragment length polymorphism. RESULTS: This study included 103 senile cataract cases (55 were males and 48 were females) and 102 controls (53 were males and 49 were females). Mean age of cases in this study was 52.02 ± 12.11 years while in control group 53.74 ± 11.87 years. Frequencies of ACE ID, DD, and II genotypes in senile cataract cases were 64.07%, 4.85%, and 31.06% and controls were 61.76%, 26.47%, and 11.76%, respectively. The CYP46A1 gene CT, CC, and TT genotype frequencies were 48.54%, 8.73%, and 42.71% in senile cataract cases and 28.43%, 3.92%, and 67.64% in healthy controls, respectively. ACE DD and II genotypes (P < 0.001,P = 0.0008) and CYP46A1 CT and TT genotypes (P = 0.003,P = 0.0003) were significantly associated with senile cataract cases compared to the controls. CONCLUSION: Findings of this study suggest that ACE and CYP46A1 genes polymorphism may be a predictive marker for early identification of population at risk of senile cataract. This potential role of ACE and CYP46A1 genes polymorphism as a marker of susceptibility to senile cataract needs further validation in studies involving larger number of patients from different regions.

8.
Middle East Afr J Ophthalmol ; 23(2): 172-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27162448

RESUMEN

PURPOSE: Glaucoma is the leading cause of irreversible blindness and the second most common cause of all blindness after cataracts. This study investigates the association of polymorphism in the CYP46A1 and PPARγ2 genes and primary open angle glaucoma (POAG). MATERIALS AND METHODS: This study evaluated 122 POAG cases (POAG group) and 112 cases of nonglaucomatous patients (control group). Polymorphisms of the CYP46A1 gene and PPARγ2 gene were evaluated with the polymerase chain reaction-restriction fragment length polymorphism method in both groups. RESULTS: The mean ages were 49.88 ± 12.34 years and 53.74 ± 11.87 years for the POAG group and control group, respectively. The CYP46A1 gene CC, CT, TT genotype frequencies were 13.93%, 58.2%, 27.87% in the POAG group and 19.6%, 40.19%, 40.19% in the control group, respectively. The PPARγ2 gene CC, CG, GG genotype frequencies were 16.83%, 54.45%, 28.71% in cases and 3.92%, 28.43%, 67.64% in the control group, respectively. Statistically, significant differences in the frequencies of CYP46A1 CC, CT, TT and PPARγ2 CC, CG, GG (P < 0.05) genotype were found between groups (P < 0.05, all comparisons). CONCLUSION: Findings of this study suggest that CYP46A1 gene and PPARγ2 gene polymorphisms can be a predictive marker for early identification of population at risk of POAG, although a larger sample size is required to determine the role of these polymorphisms in the pathogenesis and course of POAG.


Asunto(s)
Pueblo Asiatico/genética , Colesterol 24-Hidroxilasa/genética , Glaucoma de Ángulo Abierto/genética , PPAR gamma/genética , Polimorfismo Genético , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Marcadores Genéticos , Técnicas de Genotipaje , Humanos , India , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Medición de Riesgo
9.
Ophthalmic Genet ; 37(1): 19-24, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-24754249

RESUMEN

BACKGROUND: The present study was carried out to investigate the association of GST and FTO gene polymorphisms with cataract cases and controls. MATERIALS AND METHODS: The study included 131 cases and 126 controls. GST and FTO gene polymorphisms were evaluated by PCR-RFLP. RESULTS: The frequency of the GSTM1-positive and GSTT1-positive in cataract cases were 62.13% and 86.40% while in the controls it was 46.39% and 95.87% with odds ratios of 1.9 (95% CI, 1.08-3.32; p value 0.025) and 0.27 (95% CI, 0.09-0.86; p value, 0.019) respectively. There was a statistically significant association between the GSTM1 null genotype and the risk of cataract development with an odds ratio of 0.43 (95% CI, 0.24-0.76; p value, 0.003). Significant differences were obtained in the frequencies of FTO AA and TT genotype (p = 0.023 and 0.023) between cases and controls. CONCLUSION: The present study suggested that GSTM1, GSTT1 and FTO gene polymorphisms are associated with increased risk for cataract in North Indian populations. Due to the limited sample size, the finding on GST and FTO gene polymorphisms need further investigation.


Asunto(s)
Pueblo Asiatico/genética , Catarata/genética , Glutatión Transferasa/genética , Polimorfismo de Nucleótido Simple , Proteínas/genética , Adulto , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , India , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Factores de Riesgo
10.
Ann Hum Biol ; 42(5): 461-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25357227

RESUMEN

BACKGROUND: Hypertension has a multi-factorial background based on genetic and environmental interactive factors. ACE, FABP2 and GST genes have been suggested to be involved in the development of hypertension. However, the results have been inconsistent. AIM: The present study was carried out to investigate the association of ACE (rs4646994), FABP2 (rs1799883) and GST (GSTM1 null or positive genotype and GSTT1 null or positive genotype) genes polymorphism with essential HTN cases and controls. SUBJECTS AND METHODS: This study includes 138 essential hypertension (HTN) patients and 116 age-, sex- and ethnicity-matched control subjects. GST (GSTM1 null or positive genotype and GSTT1 null or positive genotype) genes polymorphisms were evaluated by multiplex PCR, ACE (rs4646994) gene polymorphisms by PCR and FABP2 (rs1799883) gene polymorphisms by PCR-RFLP method. RESULTS: Significant differences were obtained in the frequencies of ACE DD, II genotype (p = 0.006, 0.003), GSTT1 null, GSTM1 positive genotype (p = 0.048, 0.010) and FABP2 Ala54/Ala54 genotype (p = 0.049) between essential HTN cases and controls. CONCLUSION: It is concluded that ACE (rs 4646994), FABP2 (rs1799883) and GST (GSTM1 null or positive genotype and GSTT1 null or positive genotype) genes polymorphism are associated with HTN. Further investigation with a larger sample size may be required to validate this study.


Asunto(s)
Proteínas de Unión a Ácidos Grasos/genética , Glutatión Transferasa/genética , Hipertensión/genética , Peptidil-Dipeptidasa A/genética , Adulto , Estudios de Casos y Controles , Hipertensión Esencial , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , India , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple
11.
J Environ Sci Eng ; 56(3): 315-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26563083

RESUMEN

Volatile organic compounds (VOCs) are major group of air pollutants which play critical role in atmospheric chemistry. These contribute to toxic oxidants which are harmful to ecosystem, human health and atmosphere. A sampling program was conducted to determine the ambient VOC levels in the city of Agra (Uttar Pradesh), India during day time and overnight in 2010. Sampling sites were selected at three industrial area of Agra. Samples were analyzed for styrene. Concentration of Styrene was determined at different sampling points in the air of Agra in order to investigate their spatial distributions. The vertical motions of air masses also had a large impact on the variations of the level of VOC. The inter-species ratios exhibit clear seasonal variation indicating deferential reactivity of the VOCs species in different seasons.


Asunto(s)
Contaminantes Atmosféricos/análisis , Estireno/análisis , Compuestos Orgánicos Volátiles/análisis , Monitoreo del Ambiente , India , Estaciones del Año
12.
Meta Gene ; 2: 307-13, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25606413

RESUMEN

BACKGROUND: Cataract is the leading cause of bilateral blindness in India. It has been reported that cataract is responsible for 50-80% of the bilaterally blind in the country. Cataract formation is a natural part of the ageing process. At present, adequate data are not available regarding the FABP2 and PPARG2 gene polymorphisms and their susceptibility with cataract cases in the North Indian population. Thus, the present study was carried out to investigate the association of FABP2 and PPARG2 gene polymorphisms with cataract cases and controls. MATERIALS AND METHODS: This study includes 130 cataract cases and 118 controls. FABP2 and PPARG2 gene polymorphisms in cases and controls were evaluated by PCR-RFLP. RESULTS: Frequencies of Ala54Ala, Ala54Thr and Thr54Thr genotypes in FABP2 gene in cataract cases and controls were 50.76%, 39.23%, 10% and 25.42%, 61.86%, 12.71% respectively. The PPARG2 gene CC, CG, GG genotype frequencies were 11.53%, 87.69% and 0.76% in cases and 21.18%, 39.83% and 38.98% in healthy controls respectively. Significant differences were observed in the frequencies of FABP2 Ala54Ala, Ala54Thr genotype (p < 0.05) and PPARG2 CC, CG, GG genotype (p < 0.05) between cases and controls. CONCLUSION: The findings of this study suggest that FABP2 and PPARG2 gene polymorphisms can be an informative marker for early identification of population at risk of cataract. The potential role of FABP2 and PPARG2 gene polymorphisms as a marker of susceptibility to cataract needs further studies in a larger number of patients.

13.
Indian J Clin Biochem ; 25(3): 225-43, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21731194

RESUMEN

The antioxidants are essential molecules in human system but are not miracle molecules. They are neither performance enhancers nor can prevent or cure diseases when taken in excess. Their supplemental value is debateable. In fact, many high quality clinical trials on antioxidant supplement have shown no effect or adverse outcomes ranging from morbidity to all cause mortality. Several Chochrane Meta-analysis and Markov Model techniques, which are presently best available statistical models to derive conclusive answers for comparing large number of trials, support these claims. Nevertheless none of these statistical techniques are flawless. Hence, more efforts are needed to develop perfect statistical model to analyze the pooled data and further double blind, placebo controlled interventional clinical trials, which are gold standard, should be implicitly conducted to get explicit answers. Superoxide dismutase (SOD), glutathione peroxidase and catalase are termed as primary antioxidants as these scavenge superoxide anion and hydrogen peroxide. All these three enzymes are inducible enzymes, thereby inherently meaning that body increases or decreases their activity as per requirement. Hence there is no need to attempt to manipulate their activity nor have such efforts been clinically useful. SOD administration has been tried in some conditions especially in cancer and myocardial infarction but has largely failed, probably because SOD is a large molecule and can not cross cell membrane. The dietary antioxidants, including nutrient antioxidants are chain breaking antioxidants and in tandem with enzyme antioxidants temper the reactive oxygen species (ROS) and reactive nitrogen species (RNS) within physiological limits. Since body is able to regulate its own requirements of enzyme antioxidants, the diet must provide adequate quantity of non-enzymic antioxidants to meet the normal requirements and provide protection in exigent condition. So far, there is no evidence that human tissues ever experience the torrent of reactive species and that in chronic conditions with mildly enhanced generation of reactive species, the body can meet them squarely if antioxidants defense system in tissues is biochemically optimized. We are not yet certain about optimal levels of antioxidants in tissues. Two ways have been used to assess them: first by dietary intake and second by measuring plasma levels. Lately determination of plasma/serum level of antioxidants is considered better index for diagnostic and prognostic purposes. The recommended levels for vitamin A, E and C and beta carotene are 2.2-2.8 µmol/l; 27.5-30 µmol/l; 40-50 µmol/l and 0.4-0.5 µmol/l, respectively. The requirement and recommended blood levels of other dietary antioxidants are not established. The resolved issues are (1) essential to scavenge excess of radical species (2) participants in redox homeostasis (3) selective antioxidants activity against radical species (4) there is no universal antioxidant and 5) therapeutic value in case of deficiency. The overarching issues are (1) therapeutic value as adjuvant therapy in management of diseases (2) supplemental value in developing population (3) selective interactivity of antioxidant in different tissues and on different substrates (4) quantitative contribution in redox balance (5) mechanisms of adverse action on excess supplementation (6) advantages and disadvantages of prooxidant behavior of antioxidants (7) behavior in cohorts with polymorphic differences (8) interaction and intervention in radiotherapy, diabetes and diabetic complications and cardiovascular diseases (9) preventive behavior in neurological disorders (10) benefits of non-nutrient dietary antioxidants (11) markers to assess optimized antioxidants status (12) assessment of benefits of supplementation in alcoholics and heavy smokers. The unresolved and intriguing issues are (1) many compounds such as vitamin A and many others possessing both antioxidant and non-antioxidant properties contribute to both the activities in vivo or exclusively only to non-antioxidant activity and (2) since human tissues do not experience the surge of FR, whether there is any need to develop stronger synthetic antioxidants. Theoretically such antioxidants may do more harm than good.

14.
J Med Food ; 11(3): 506-12, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18800899

RESUMEN

In the present investigation we report the protective potential of some herbal hypoglycemic agents on antioxidant status and levels of metal ions in streptozotocin-induced diabetic rats. Furthermore, in vitro antioxidant activity of the herbs was also evaluated. Induction of diabetes mellitus in rats caused an increase in blood lipid peroxide levels that was associated with the reduced activity of red blood cell (RBC) antioxidant enzymes--namely, superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase--along with depletion of plasma reduced glutathione (GSH) and copper, zinc, iron, magnesium, and selenium levels. Oral treatment of diabetic rats with Allium sativum, Azadirachta indica, Momordica charantia, and Ocimum sanctum extracts (500 mg/kg of body weight) not only lowered the blood glucose level but also inhibited the formation of lipid peroxides, reactivated the antioxidant enzymes, and restored levels of GSH and metals in the above-mentioned model. The herbal extracts (50-500 microg) inhibited the generation of superoxide anions (O(2)(-.)) in both enzymatic and nonenzymatic in vitro systems. These preparations also inhibited the ferrous-sodium ascorbate-induced formation of lipid peroxides in RBCs. The in vivo and in vitro protective effects of the above-mentioned herbal drugs were also compared with that of glibenclamide. On the basis of our results, we conclude that the above-mentioned herbal plants not only possess hypoglycemic properties, but they also decrease oxidative load in diabetes mellitus. Therefore, we propose that long-term use of such agents might help in the prevention of diabetes-associated complications. However, the extrapolation of these results to humans needs further in-depth study.


Asunto(s)
Antioxidantes/metabolismo , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/farmacología , Fitoterapia , Animales , Antioxidantes/farmacología , Glucemia/efectos de los fármacos , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/metabolismo , Glutatión/sangre , Hipoglucemiantes/uso terapéutico , India , Peroxidación de Lípido/efectos de los fármacos , Masculino , Estrés Oxidativo/efectos de los fármacos , Plantas Medicinales , Ratas , Oligoelementos/metabolismo , Xantina/metabolismo
15.
Indian J Clin Biochem ; 18(2): 8-15, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23105386

RESUMEN

In the present study the antioxidative potential ofMomordica charantia, Azadirachta indica, Allium sativum andOcimum sanctum was assessed in streptozotocin induced diabetic rats. Lipid peroxide levels were also measured in normal, diabetic and treated animals. Malondialdehyde (MDA) levels were significantly higher and antioxidant activity was found low in diabetic groups as compared to the control groups, and significant alteration in both the MDA levels and antioxidant activity was also observed when the above herbal hypoglycemic agents were given to diabetic rats. On the basis of our results we conclude thatM. charantia, A. indica, A. sativum andO. sanctum are not only useful in controlling the lipid peroxide levels but are also helpful in further strengthening the antioxidant potential.

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