共查询到20条相似文献,搜索用时 26 毫秒
1.
R. Manikandan R. Thiagarajan S. Beulaja S. Chindhu K. Mariammal G. Sudhandiran M. Arumugam 《Chemico-biological interactions》2009,181(2):202-209
The aim of this study was to investigate whether curcumin and aminoguanidine (AG) prevent selenium-induced cataractogenesis in vitro. On postpartum day 8, transparent isolated lens were incubated in 24 well plates containing Dulbecco's Modified Eagle Medium (DMEM). Isolated lens of group I were incubated with DMEM medium alone. Group II: lenses incubated in DMEM containing 100 μM sodium selenite; group III: lenses incubated in DMEM containing 100 μM sodium selenite and 100 μM curcumin; group IV: lenses incubated in DMEM containing 100 μM sodium selenite and 200 μM curcumin; group V: lenses incubated in DMEM containing 100 μM sodium selenite and 100 μM AG; group V: lenses incubated in DMEM containing 100 μM sodium selenite and 200 μM AG. On day 12, cataract development was graded using an inverted microscope and the lenses were analyzed for enzymic as well as non-enzymic antioxidants, lipid peroxidation (LPO), nitric oxide (NO), superoxide anion (O2−) and hydroxyl radical generation (OH) and inducible nitric oxide synthase (iNOS) activity by Western blotting and RT-PCR. All control lenses in group I were clear (0). In groups II and III, all isolated lenses developed cataract with variation in levels (+++ or ++), whereas isolated lenses from groups IV, V and VI were clear (0). In agreement to this, a decrease in antioxidants and increased free radical generation and also iNOS expression were observed in selenium exposed lenses when compared to other groups. AG (100 μM) was found to be more effective in anti-cataractogenic effect than curcumin (200 μM). Curcumin and AG suppressed selenium-induced oxidative stress and cataract formation in isolated lens from Wistar rat pups, possibly by inhibiting depletion of enzymic as well as non-enzymic antioxidants, and preventing uncontrolled generation of free radicals and also by inhibiting iNOS expression. Our results implicate a major role for curcumin and AG in preventing cataractogenesis in selenite-exposed lenses, wherein AG was found to be more potent. 相似文献
2.
B. N. Rooban V. Sasikala V. Sahasranamam Annie Abraham 《Biological trace element research》2010,138(1-3):282-292
Recently, much interest has been generated in the search for phytochemical therapeutics, as they are largely free from adverse side effects and economical. The goal of this study was to determine the efficacy of Vitex negundo in modulating the selenite-induced oxidative stress in vivo model. Sprague–Dawley rat pups of 8 days old were used for the study and divided into control (G I), selenite induced (G II), and selenite + V. negundo treated (G III). Cataract was induced by the single subcutaneous injection of sodium selenite (4 mg/kg body weight) on the tenth day and V. negundo (2.5 mg/Kg body weight) administered intraperitoneally from eighth to 15th day. Morphological examination of the rat lenses revealed no opacification in G I and mild opacification in G III whereas dense opacification in G II (stages 4–6). Levels of selenium in G II and G III showed no significant changes. The activities of superoxide dismutase, catalase, and Ca2+ATPase were significantly increased in G III compared to G II (p?<?0.05), while lower level of reactive oxygen species, Ca2+, and thiobarbituric acid reactive substances were observed in G III compared G II (p?<?0.05). These results indicate the therapeutic potential of methanolic extract of V. negundo on modulating biochemical parameters against selenite-induced cataract, which have been reported in this paper for the first time. 相似文献
3.
Suresh K. Gupta Vivekananthan Kalaiselvan Sushma Srivastava Rohit Saxena Shyam S. Agrawal 《Biological trace element research》2010,136(3):258-268
Cataract is the opacification in eye lens and leads to 50% of blindness worldwide. The present study was undertaken to evaluate
the anticataract potential of Trigonella foenum-graecum Linn seeds (fenugreek) in selenite-induced in vitro and in vivo cataract. In vitro enucleated rat lenses were maintained
in organ culture containing Dulbecco’s modified Eagles medium (DMEM) alone or in addition with 100 μM selenite and served
as the normal and control groups, respectively. For the test group, the medium was supplemented with selenite and T. foenum-graecum aqueous extract. The lenses were incubated for 24 h at 37°C. After incubation, the lenses were processed for the estimation
of reduced glutathione (GSH), lipid peroxidation product (malondialdehyde), and the antioxidant enzymes. In vivo selenite
cataract was induced in 9-day-old rats by subcutaneous injection of sodium selenite (25 μmol/kg body weight). Animals in the
test group were injected with different doses of aqueous extract of T. foenum-graecum 4 h before the selenite challenge. A fall in GSH and a rise in malondialdehyde levels were observed in control as compared
to normal lenses. T. foenum-graecum significantly (P < 0.01) restored glutathione and decreased malondialdehyde levels. A significant restoration in the activities of antioxidant
enzymes such as superoxide dismutase (P < 0.01), catalase, (P < 0.01), glutathione peroxidase (P < 0.01), and glutathione-S-transferase (P < 0.01) was observed in the T. foenum-graecum supplemented group as compared to control. In vivo, none of the eyes was found with nuclear cataract in treated group as
opposed to 72.5% in the control group. T. foenum-graecum protects against experimental cataract by virtue of its antioxidant properties. Further studies are warranted to explore
its role in human cataract. 相似文献
4.
Rooban BN Sasikala V Gayathri Devi V Sahasranamam V Abraham A 《Chemico-biological interactions》2012,196(1-2):30-38
Free radical mediated oxidative stress plays a crucial role in the pathogenesis of cataract and the present study was to determine the efficacy of luteolin in preventing selenite induced oxidative stress and cataractogenesis in vitro. Luteolin is a bioactive flavonoid, isolated and characterized from the leaves of Vitex negundo. Lenses were extracted from Sprague-Dawley strain rats and were organ cultured in DMEM medium. They were divided into three groups with eight lenses in each group as follows: lenses cultured in normal medium (G I), supplemented with 0.1mM sodium selenite (G II) and sodium selenite and 2 μg/ml luteolin (G III). Treatment was from the second to fifth day, while selenite administration was done on the third day. After the experimental period, lenses were taken out and various parameters were studied. The antioxidant potential of luteolin was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. In the selenite induced group, morphological examination of the lenses showed dense cortical opacification and vacuolization. Biochemical examinations revealed a significant decrease in activities of antioxidant enzymes and enzymes of the glutathione system. Additionally decreased glutathione level and increased reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) were observed. Luteolin treatment abated selenite induced oxidative stress and cataractogenesis by maintaining antioxidant status, reducing ROS generation and lipid peroxidation in the lens. These finding demonstrated the anticataractogenic effect of luteolin by virtue of its antioxidant property, which has been reported in this paper for the first time. 相似文献
5.
Rasiah Pratheepa Kumari Jeyarajan Sivakumar Bency Thankappan Kumarasamy Anbarasu 《Biological trace element research》2013,151(1):59-67
The present investigation is aimed to evaluate the anticataractogenic potential of C-phycocyanin (C-PC), extracted and purified from Spirulina platensis. Enucleated rat lenses were maintained in vitro in Dulbecco’s modified Eagle medium (DMEM). Group I contained DMEM, Group II and Group III contained 100 μM of sodium selenite, Group III was subdivided into three viz IIIa, IIIb, IIIc supplemented with 100, 150, 200 μg of C-PC respectively. In the in vivo study, on tenth day post partum: Group I rat pups received an intraperitoneal injection of saline, Group II, IIIa, IIIb, and IIIc rat pups received a subcutaneous injection of sodium selenite (19 μmol/kg bodyweight) Group IIIa, IIIb, IIIc also received an intraperitoneal injection of 100, 150, 200 mg/kg body weight of C-PC, respectively, from postpartum days?9–14. On termination of the experiment, the lenses from both in vitro and in vivo studies were subjected to morphological examination and subsequently processed to estimate the activities of antioxidant enzymes namely superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, levels of reduced glutathione and lipid peroxidation products. Sodium selenite-exposed, C-PC-treated rat lenses (Group IIIc), showed significant restoration of antioxidant enzyme activity (p?<?0.05) when compared to their counterpart Group II. Group IIIc conserved the levels of GSH and lipid peroxidation products at near to normal levels as compared with Group II. Results conclude the possible role of C-PC in modulating the antioxidant enzyme status, thereby retarding sodium selenite-induced cataract incidence both in vitro and in vivo. 相似文献
6.
7.
Tao Wang Peng Zhang Chunfeng Zhao Yi Zhang Hong Liu Limin Hu Xiumei Gao Deqin Zhang 《Biological trace element research》2011,142(1):106-116
Cataract is the leading cause of blindness worldwide. It is a multifactorial disease primarily associated with oxidative stress
produced by free radicals. The present study was undertaken to evaluate the anticataract potential of Crataegus pinnatifida (hawthorn tree) leaves extract in selenite-induced cataract in vivo and antioxidant effects in vitro. In vitro antioxidant
assay of C. pinnatifida leaves extract on NO production inhibition, aldose reductase inhibition, and O2- radical scavenging activities gave the IC50 of 98.3, 89.7, and 5.98 μg/mL, respectively. To characterize some major compounds in C. pinnatifida leaves extract, nine flavonoids were identified via LC–MS/MS qualitative analysis. Based on in vitro screening results, C. pinnatifida leaves extract eye drops in 0.1% hydroxypropyl methyl cellulose solution were prepared to evaluate the anticataract potential
in vivo. Administration of C. pinnatifida leaves extract eye drops alternately three times a day in rat pups with selenite-induced oxidative stress significantly increased
serum SOD and CAT activities, and tended to reduce MDA level compared with control group. The antioxidant enzyme SOD, CAT,
and GSH activities in lens showed a significant increase. These results may be applied in the future for the prevention and
treatment of cataracts. 相似文献
8.
Liying Guan Binshe Han Zhushi Li Fangyuan Hua Fang Huang Wei Wei Yang Yang Caimin Xu 《Apoptosis : an international journal on programmed cell death》2009,14(2):218-225
Introduction In this study, we delineated the apoptotic signaling pathways activated by sodium selenite in NB4 cells.
Materials and methods NB4 cells were treated with 20 μM sodium selenite for different times. The activation of caspases and ER stress markers, ROS
levels, mitochondrial membrane potential and cell apoptosis induced by sodium selenite were analyzed by immunoblotting analysis,
DCF fluorescence and flow cytometric respectively. siRNA was used to detect the effect of GADD153 on selenite-induced cell
apoptosis.
Conclusions Sodium selenite-induced reactive oxygen species generation is an early event that triggers endoplasmic reticulum stress mitochondrial
apoptotic pathways in NB4 cells. 相似文献
9.
S. S. Swathy Seema Panicker R. S. Nithya M. M. Anuja S. Rejitha M. Indira 《Neurochemical research》2010,35(9):1361-1367
Sida cordifolia is a plant belonging to the Malvaceae family used in many ayurvedic preparations. This study aimed at assessing the effects
of ethanolic extract of Sida cordifolia root on quinolinic acid (QUIN) induced neurotoxicity and to compare its effect with the standard drug deprenyl in rat brain.
Rats were divided into six groups: (1) control group (2) QUIN (55 μg/100 g bwt/day) (3) 50% ethanolic plant extract treated
group (50 mg/100 g bwt/day) (4) Deprenyl (100 μg/100 g bwt/day) (5) QUIN (55 μg/100 g bwt/day) + 50% ethanolic plant extract
treated group (50 mg/100 g bwt/day) (6) QUIN (55 μg/100 g bwt/day) + Deprenyl (100 μg/100 g bwt/day). At the end of the experimental
period a status of lipid peroxidation products, protein peroxidation product, activities of the scavenging enzymes and the
activities of the inflammatory markers were analyzed. Results revealed that the lipid peroxidation products decreased and
the activities of the scavenging enzymes increased significantly in the brain of the plant extract treated group, deprenyl
treated group and also in the coadminstered groups. The activities of markers of inflammatory responses such as cyclooxygenase
and lipoxygenase were found to be significantly increased in the QUIN treated rats and this was decreased upon the administration
of plant extract and deprenyl. In short, the study revealed that 50% ethanolic extract of Sida cordifolia has got potent antioxidant and antiinflammatory activity and the activity is comparable with the standard drug deprenyl. 相似文献
10.
Selenium, an essential biological trace element present in both prokaryotic and eukaryotic cells, exerts its regulatory effect
in a variety of cellular events, including cell growth, survival, and death. Selenium compunds have been shown in different
cell lines to inhibit apoptosis by several mechanisms. Serine/threonine phosphatases (STPs) are potentially important in selenite-induced
apoptosis because of their role in regulation of diverse set of cellular processes. In this study, the regulatory role of
STPs in selenite-induced apoptosis has been implied by the use of two specific inhibitors: ocadaic acid and calyculin A. Our
results show a decrease in cell density in HepG2 cells under selenite treatment. Resulting specific enzyme activities showed
a concentration-dependent increase in all three phosphatase activities after 24 h in cells treated with 5 μM selenite and
these activities decreased at 48 and 72 h. However, in cells treated with 10μM selenite, PP2A and PP2B decreased at 48 h, whereas PP2C activity did not change at this dose. In cells treated with 25μM, there was not a significant change in PP2C activity. These data suggest that the most specific response to selenite treatment
was in PP2A and PP2B activities in a dose-dependent manner. Our results with OA and Cal-A further support the view that PP1
and PP2A might act as negative regulators of growth. With these data, we have first demonstrated the role of serine/threonine
protein phosphatases in the signaling pathway of selenite-induced apoptosis and resulting cytotoxicity 相似文献
11.
Shi D Guo S Liao S Su R Guo M Liu N Li P Tang Z 《Biological trace element research》2012,145(3):312-317
To investigate the protection of selenium on hepatic mitochondrial functions, 90 7-day-old ducklings were randomly divided
into three groups (groups I–III). Group I was used as a blank control. Group II was administered with aflatoxin B1 (0.1 mg/kg body weight). Group III was administered with aflatoxin B1 (0.1 mg/kg body weight) plus selenium (sodium selenite, 1 mg/kg body weight). All treatments were given once daily for 21 days.
The results showed that the activities of hepatic mitochondrial complexes I–IV in group II ducklings significantly decreased
when compared with group I (P < 0.01). Furthermore, the activities of hepatic mitochondrial complexes I–IV in group III significantly increased when compared
with group II (P < 0.05). The hepatic mitochondrial respiratory control ratio (RCR) in group II ducklings significantly decreased when compared
with group I (P < 0.01). In addition, the hepatic mitochondrial RCR in group III significantly increased when compared with group II (P < 0.05). These results revealed that the aflatoxin B1 significantly induced hepatic mitochondrial dysfunction in the activities of hepatic mitochondrial respiratory chain complexes
I–IV and the RCR in ducklings. However, sodium selenite could significantly ameliorate the negative effect induced by aflatoxin
B1. 相似文献
12.
Annadurai T Vigneshwari S Thirukumaran R Thomas PA Geraldine P 《Journal of physiology and biochemistry》2011,67(4):519-530
Acetyl-l-carnitine (ALCAR) has been shown to prevent experimental selenite cataractogenesis, a manifestation of oxidative stress,
but little is known about its potential in other settings of oxidative stress. The present study was based on the hypothesis
that ALCAR prevents carbon tetrachloride (CCl4)-induced oxidative stress in vital tissues. Male albino Wistar rats were divided into three groups, each of six rats. Group
I (control) rats received only vehicle (1 ml/kg b.w.) for 4 days; Group II (CCl4-exposed, untreated) rats received CCl4 (2 ml/kg b.w.) on the second and third days and vehicle on the first and fourth days; Group III (CCl4-exposed, ALCAR-treated) rats received ALCAR (200 mg/kg b.w.) for 4 days and CCl4 on the second and third days. All administrations were made intraperitoneally. After the experimental period, significantly
(P < 0.05) elevated mean serum levels of aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase
were observed in Group II rats when compared to Group I and Group III rats. The mean levels of vitamin C, vitamin E, and reduced
glutathione and the mean activities of superoxide dismutase, catalase, and glutathione peroxidase were significantly (P < 0.05) lower in samples of hemolysate and of liver, kidney, and brain tissues of Group II rats than those in Group I and
Group III rats. The mean level of lipid peroxidation was significantly (P < 0.05) higher in Group II rats than that in Group I and Group III rats. Moreover, the CCl4-induced upregulation of inducible nitric oxide synthase expression was prevented by ALCAR in the liver and brain tissues.
These results suggest that ALCAR is able to prevent the CCl4-induced oxidative stress. 相似文献
13.
The aim of the study was to investigate the effect of selenium on hepatic mitochondrial antioxidant capacity in ducklings
administrated with aflatoxin B1 (AFB1). Ninety 7-day-old ducklings were randomly divided into three groups (groups I–III). Group I was used as a blank control.
Group II was administered with AFB1 (0.1 mg/kg body weight). Group III was administered with AFB1 (0.1 mg/kg body weight) plus selenium (sodium selenite, 1 mg/kg body weight). All treatments were given once daily for 21 days.
The results showed that the activities of mitochondrial superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase
(GSH-Px), and glutathione reductase (GR) in group II ducklings significantly decreased when compared with group I (P < 0.01). Furthermore, the content of hepatic mitochondrial malondialdehyde (MDA) significantly increased (P < 0.01). However, the activities of hepatic mitochondrial SOD, CAT, GSH-Px, and GR in group III ducklings significantly increased
when compared with group II (P < 0.05). In addition, the content of hepatic mitochondrial MDA significantly decreased (P < 0.01). These results revealed that AFB1 significantly induced hepatic mitochondrial antioxidant dysfunction. However, sodium selenite could significantly ameliorate
the negative effect induced by AFB1. 相似文献
14.
It is known that the subcutaneous injection of a single dose of sodium selenite into suckling rats results in the development
of large nuclear opacities. The intracellular transport of selenite in various cells, except lens cells, occurs via the Cl/HCO3 exchanger. The aim of the present study is to investigate the possible role of the anion-exchange inhibitor, disulfonic stilbene
(SITS), in the selenite-induced catarogenesis in the rat pups. Wistar albino rats (8–10 d old) were separated into three groups:
one control and two experimental. The first experimental group was injected subcutaneously with a single dose of 30 nmol sodium
selenite/g body weight. The second experimental group was injected with a single dose of 10 nmol SITS/g body weight 15 min
before the same dose selenite injection. The control group did not have any injections. The stage of cataract development
was examined on d 7 postinjection with slit-lamp photographs. In SITS pretreated group, all eyes remained transparent (considered
as stage 0), whereas in the selenite-injected group, the animals did have different stage of nuclear cataract; 8 animals have
stage 5, 10 animals have stage 4, and 4 animals have stage 3. A pretreatment of SITS completely prevented cataract formation
of the selenite-induced cataract model in rat pups. 相似文献
15.
Luteolin Supplementation Prevents Selenite‐Induced Cataractogenesis in Sprague Dawley Rat Pups
下载免费PDF全文
![点击此处可从《化学与生物多样性》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Luteolin, a flavonoid present in leaves and stems of many plants finds mention in literature for beneficial effects on eyes. Presently, no reports are available on the in vivo anticataractogenic effect of luteolin. The current study was designed to evaluate the efficacy of luteolin on selenite‐induced cataract models in vivo. The study consisted of three groups of Sprague Dawley rat pups 8–10 d old (Group I (Normal), Group II (Cataract induced), and Group III (Treatment)). Cataract was induced in Group II and Group III by a subcutaneous injection of sodium selenite (4 μg/g body weight) on the 10th day. Luteolin was administered orally from 8th day up to 12th day at a concentration of 1 μg/g body weight in Group III. After 30 d, lenses of treated animals showed normal morphology. Activities of antioxidant enzymes were increased and levels of reactive oxygen species were decreased in the luteolin‐treated group when compared to the cataract‐induced group. Increased Ca2+ATPase activity and lowered calcium level, caspase 3 activity and down‐regulation of caspase 3 expression were seen in the treatment group when compared to the selenite group. Luteolin enhances the antioxidant potential and thereby lowers the oxidative damages to the lens. It also stabilizes the membrane integrity of the lens and maintains the ionic balance. 相似文献
16.
To investigate the influence of selenium on body weights and the immune organ indexes in ducklings administrated with aflatoxin
B1 (AFB1), 90 7-day-old ducklings were randomly divided into three groups (groups I–III). Group I was used as a blank control. Group
II was administered with AFB1 (0.1 mg/kg body weight). Group III was administered with AFB1 (0.1 mg/kg body weight) plus sodium selenite (1 mg/kg body weight). All treatments were given once daily for 21 days. It
showed that the ducklings’ bursa of fabricius, thymus indexes, and body weights in group II significantly decreased when compared
with group I (P < 0.01). Furthermore, the spleen indexes significantly decreased (P < 0.01). However, the ducklings’ bursa of fabricius and thymus indexes, body weights in group III ducklings significantly
increased when compared with group II (P < 0.01). In addition, the spleen indexes significantly decreased (P < 0.01). These results revealed that AFB1 significantly affect ducklings’ growth and immune organs development. However, selenium significantly ameliorated the negative
effects induced by AFB1. 相似文献
17.
The sodium/iodide symporter (SLC5A5, also known as NIS) is a transmembrane glycoprotein. Physiologically, iodide transportation in the mammary gland occurs during late pregnancy
and lactation. To identify factors that may regulate this process at different iodine levels, we have studied the expression
of NIS gene and protein in cultured mammary gland explants from lactating mice by real-time quantitative PCR and In-Cell Western
methods. Mammary gland cells were grown in media with different levels of iodine for 24 h. The iodine treatment groups consist
of low iodine group I (LI-I, 0 μg/l), low iodine group II (LI-II, 5 μg/l), control group (C, 50 μg/l), high iodine group I
(HI-I, 3,000 μg/l), and high iodine group II (HI-II, 10,000 μg/l). The cells were then incubated with or without insulin-like
growth factor I (IGF-I) or transforming growth factor β1 (TGF-β1) for another 24 h. We found that iodine inhibited NIS mRNA and protein expression in a dose-dependent manner. IGF-I and TGF-β1 further decreased NIS mRNA and protein expression that iodine inhibited at different iodine levels. In summary, we have shown that iodine downregulated
NIS expression in cultured mammary gland explants from the lactating mouse. IGF-I and TGF-β1 inhibited NIS mRNA and protein expression in the mammary gland under different iodine levels. 相似文献
18.
Asfour IA El-Tehewi MM Ahmed MH Abdel-Sattar MA Moustafa NN Hegab HM Fathey OM 《Biological trace element research》2009,127(3):200-210
The present study was undertaken to explore the effect of administration of high doses of sodium selenite on the apoptosis
of lymphoma cells in patients with non-Hodgkin’s lymphoma (NHL). Forty patients with newly diagnosed NHL were randomly divided
into two groups. Group I received standard chemotherapy, whereas group II received adjuvant sodium selenite 0.2 mg kg−1 day−1 for 7 days in addition to chemotherapy. Flow cytometry was used for monitoring of lymphoma cells apoptosis at the time of
diagnosis and after therapy in the two groups. Sodium selenite administration resulted in significant increase in percentage
of apoptotic lymphoma cells after therapy in group II (78.9 ± 13.3% versus 58.9 ± 18.9%, p < 0.05). In addition, patients who received sodium selenite treatment demonstrated statistically significant increase in
percentage of reduction of cervical and axillary lymphadenopathy, decrease in splenic size, and decreased percentage of bone
marrow infiltration. Also, we found a statistically significant decrease in cardiac ejection fraction (CEF) in group I and
no reduction in CEF in patients who received sodium selenite ‘group II’, denoting the cardioprotective effect of selenium.
It is concluded that sodium selenite administration at the dosage and duration chosen has synergistic effect to chemotherapy
in inducing apoptosis and, consequently, could improve clinical outcome. 相似文献
19.
Regalado EL Rodríguez M Menéndez R Concepción AA Nogueiras C Laguna A Rodríguez AA Williams DE Lorenzo-Luaces P Valdés O Hernandez Y 《Marine biotechnology (New York, N.Y.)》2009,11(1):74-80
Daily topical application of the aqueous ethanolic extract of the marine sea grass, Thalassia testudinum, on mice skin exposed to UVB radiation resulted in a dose-dependent recovery of the skin macroscopic alterations over a 6-day
period. Maximal effect (90%) occurred at a dose of 240 μg/cm2, with no additional effects at higher doses. Bioassay-guided fractionation of the plant extract resulted in the isolation
of thalassiolin B (1). Topical application of 1 (240 μg/cm2) markedly reduces skin UVB-induced damage. In addition, thalassiolin B scavenged 2,2-diphenyl-2-picrylhydrazyl radical with
an EC50 = 100 μg/ml. These results suggest that thalassiolin B is responsible for the skin-regenerating effects of the crude extract
of T. testudinum.
Erik L. Regalado and María Rodríguez have contributed equally to this work and should be considered as first authors. 相似文献
20.
Peng X Cui H He Y Cui W Fang J Zuo Z Deng J Pan K Zhou Y Lai W 《Biological trace element research》2012,145(1):47-51
Three hundred 1-day-old avian broilers were fed on a basic diet (0.2 mg/kg selenium) or the same diet amended to contain 1,
5, 10, and 15 mg/kg selenium supplied as sodium selenite (n = 60/group). In comparison with those of 0.2 mg/kg selenium group, the percentages of annexin V-positive splenocytes were
increased in 5, 10, and 15 mg/kg selenium groups. TUNEL assay revealed that apoptotic cells with brown-stained nuclei distributed
within the red pulp and white pulp of the spleens with increased frequency of occurrence in 10 and 15 mg/kg selenium groups
in comparison with that of 0.2 mg/kg Se group. Sodium selenite-induced oxidative stress in spleens of chickens was evidenced
by decrease in glutathione peroxidase, superoxide dismutase, and catalase activities and increase in malondialdehyde contents.
The results indicate that excess dietary selenium in the range of 5–15 mg/kg of feed causes oxidative stress, which may be
mainly responsible for the increased apoptosis of splenocytes in chickens. 相似文献