The efficacy of vitamin E in preventing arthrofibrosis after joint replacement

Background:Arthrofibrosis is a joint disorder characterized by excessive scar formation in the joint tissues.Vitamin E is an antioxidant with potential anti-fibroblastic effect.The aim of this study was to establish an arthrofibrosis rat model after joint replacement and assess the effects of vitamin E supplementation on joint fibrosis.Methods:We simulated knee replacement in 16 male Sprague–Dawley rats.We immobilized the surgical leg with a suture in full flexion.The control groups were killed at 2 and 12 weeks(n=5 per group),and the test group was supplemented daily with vitamin E(0.2 mg/mL)in their drinking water for 12 weeks(n=6).We performed histological staining to investigate the presence and severity of arthrofibrosis.Immunofluorescent staining andα2-macroglobulin(α2M)enzyme-linked immunosorbent assay(ELISA)were used to assess local and systemic inflammation.Static weight bearing(total internal reflection)and range of motion(ROM)were collected for functional assessment.Results:The ROM and weight-bearing symmetry decreased after the procedure and recovered slowly with still significant deficit at the end of the study for both groups.Histological analysis confirmed fibrosis in both lateral and posterior periarticular tissue.Vitamin E supplementation showed a moderate anti-inflammatory effect on the local and systemic levels.The vitamin E group exhibited significant improvement in ROM and weight-bearing symmetry at day 84 compared to the control group.Conclusions:This model is viable for simulating arthrofibrosis after joint replacement.Vitamin E may benefit postsurgical arthrofibrosis,and further studies are needed for dosing requirements.

Vitamin E in the management of pancreatic cancer: A scoping review

Pancreatic cancer is the leading cause of cancer mortality worldwide.Research investigating effective management strategies for pancreatic cancer is ongoing.Vitamin E,consisting of both tocopherol and tocotrienol,has demonstrated debatable effects on pancreatic cancer cells.Therefore,this scoping review aims to summarize the effects of vitamin E on pancreatic cancer.In October 2022,a literature search was conducted using PubMed and Scopus since their inception.Original studies on the effects of vitamin E on pancreatic cancer,including cell cultures,animal models and human clinical trials,were considered for this review.The literature search found 75 articles on this topic,but only 24 articles met the inclusion criteria.The available evidence showed that vitamin E modulated proliferation,cell death,angiogenesis,metastasis and inflammation in pancreatic cancer cells.However,the safety and bioavailability concerns remain to be answered with more extensive preclinical and clinical studies.More in-depth analysis is necessary to investigate further the role of vitamin E in the management of pancreatic cancers.

Complexity of vitamin E metabolism

Bioavailability of vitamin E is influenced by several factors, most are highlighted in this review. While gender, age and genetic constitution influence vitamin E bioavailability but cannot be modified, life-style and intake of vitamin E can be. Numerous factors must be taken into account however, i.e., when vitamin E is orally administrated, the food matrix may contain competing nutrients. The complex metabolic processes comprise intestinal absorption, vascular transport, hepatic sorting by intracellular binding proteins, such as the significant α-tocopherol-transfer protein, and hepatic metabolism. The coordinated changes involved in the hepatic metabolism of vitamin E provide an effective physiological pathway to protect tissues against the excessive accumulation of, in particular, non-α-tocopherol forms. Metabolism of vitamin E begins with one cycle of CYP4F2/CYP3A4-dependent ω-hydroxylation followed by five cycles of subsequent β-oxidation, and forms the water-soluble end-product carboxyethylhydroxychroman. All known hepatic metabolites can be conjugated and are excreted, depending on the length of their sidechain, either via urine or feces. The physiological handling of vitamin E underlies kinetics which vary between the different vitamin E forms. Here, saturation of the side-chain and also substitution of the chromanol ring system are important. Most of the metabolic reactions and processes that are involved with vitamin E are also shared by other fat soluble vitamins. Influencing interactions with other nutrients such as vitamin K or pharmaceuticals are also covered by this review. All these processes modulate the formation of vitamin E metabolites and their concentrations in tissues and body fluids. Differences in metabolism might be responsible for the discrepancies that have been observed in studies performed in vivo and in vitro using vitamin E as a supplement or nutrient. To evaluate individual vitamin E status, the analytical procedures used for detecting and quantifying vitamin E and its metabolites are crucial. The latest methods in analytics are presented.

Conjugation of Candida rugosa lipase with hydrophobic polymer improves esterification activity of vitamin E in nonaqueous solvent

We described a novel polymer-lipase conjugate for high-efficient esterification of vitamin E using vitamin E and succinic anhydride as the substrates in nonaqueous media.In this work,the monomer,N-isopropylacrylamide(NIPAM),was grafted onto Candida rugosa lipase(CRL)to synthesize poly(NIPAM)(pNIPAM)-CRL conjugate by atom transfer radical polymerization via the initiator coupled on the surface of CRL.The result showed that the catalytic efficiencies of pNIPAM-CRL conjugates(19.5-30.3 L·s^(-1)·mmol^(-1))were at least 7 times higher than that of free CRL(2.36 L·s^(-1)·mmol^(-1))in DMSO.It was attributed to a significant increase in Kcat of the conjugates in nonaqueous media.The synthesis catalyzed by pNIPAM-CRL co njugates was influenced by the length and density of the grafted polymer,water content,solvent polarity and molar ratio of the substrates.In the optimal synthesis,the reaction time was shortened at least 7 times,and yields of vitamin E succinate by pNIPAM-g-CRL and free CRL were obtained to be 75.4%and 6.6%at 55℃after the reaction for 1.5 h.The result argued that conjugation with pNIPAM induced conformational change of the lid on CRL based on hydrophobic interaction,thus providing a higher possibility of catalysis-favorable conformation on CRL in nonaqueous media.Moreover,pNIPAM conjugation improved the thermal stability of CRL greatly,and the stability improved further with an increase of chain length of pNIPAM.At the optimal reaction conditions(55℃and 1.5 h),pNIPAM-g-CRL also exhibited good reusability in the enzymatic synthesis of vitamin E succinate and kept~70%of its catalytic activity after ten consecutive cycles.The research demonstrated that pNIPAM-g-CRL was a more competitive biocatalyst in the enzymatic synthesis of vitamin E succinate and exhibited good application potential under harsh industrial conditions.

Vitamin E modulates androgen receptor gene expression to attenuate ovarian dysfunctions in a rat model of dehydroepiandrosterone-induced polycystic ovary

Objective:To investigate the protective effect of vitamin E in dehydroepiandrosterone(DHEA)-induced polycystic ovary in rats.Methods:Premature female Wistar rats were randomly allocated into four groups,with 7 rats in each group.Group栺received corn oil(vehicle)and served as the control group;group栻received 0.2 mL of 0.06 mg/g DHEA in corn oil;group栿received 200 mg/kg vitamin E;group桇received DHEA plus vitamin E.All treatments lasted for 15 days,with DHEA administered subcutaneously,while vitamin E and corn oil were administered orally.After the experiment,serum samples and ovaries were harvested for biochemical,immunohistochemical,hormonal,and histological analysis.The ovarian mRNA expression of androgen receptor was analyzed by reverse transcriptase quantitative polymerase chain reaction(qPCR).Results:The antioxidant and metabolic enzyme activity significantly decreased in the DHEA-treated rats compared to the control rats(P<0.05).Administration of vitamin E to DHEAtreated rats significantly decreased cytokines and malondialdehyde compared to the DHEA-treated rats.The histological analysis showed reduced atretic and cystic ovaries,increased E-cadherin and Bcl-2 expression,and reduced expression of Bax in the DHEAtreated rats co-treated with vitamin E.The mRNA expression of androgen receptor was upregulated in the DHEA-treated rats compared to the control rats.Conclusions:Vitamin E ameliorates the hyperandrogenic effect of DHEA-induced polycystic ovaries via metabolic,antioxidant,and anti-apoptotic pathways.

A comparison of the effect of Vitamin D and Vitamin E supplementations,alone,and in combination,on reducing the intensity and duration of dysmenorrhea in women:A randomized controlled trial

Objective:The aim of this study is to compare the effect of Vitamin D and Vitamin E supplementations,alone,and in combination,on reducing the intensity and duration of dysmenorrhea in women who were referred to the Kowsar gynecological clinics of Shahid Motahari Hospital of Urmia University of Medical Sciences.Materials and Methods:A double-blinded clinical trial was conducted on 112 women with dysmenorrhea who were randomly allocated into the four study groups.Finally,100 women complete the study and received capsules containing a placebo(n=25),1000 IU of Vitamin D(n=25),400 mg of Vitamin E(n=25),and 1000 IU of Vitamin D+400 mg of Vitamin E(n=25)every 24 h for 2 consecutive months at the beginning of the menstrual period.The pain intensity and duration among groups were compared before and after the intervention.Results:The mean menstrual pain duration in all three experimental groups(Vitamin E,Vitamin D,and the combination of them)was lower than the placebo group(all P<0.05),and the mean pain intensity scores in all three experimental groups were significantly lower than the placebo group(all P<0.05).The results(means)for all of the drugs administered at the end of the 2nd month were better than the 1st month(all P<0.01).Conclusions:Vitamin E and Vitamin D,as well as their combination,are recommended as an effective and safe treatment for the management of the complications of dysmenorrhea.

Serum Vitamin E Reference Intervals in a Black Congolese Population of Kinshasa

Context: Vitamin E is a powerful antioxidant and plays an important role in human reproduction. However, micronutrient deficiency is a major public health problem, particularly in developing countries. This study aimed to establish reference intervals (RIs) for vitamin E in black Congolese people of childbearing age using an ELISA method to provide a reference for clinically assessing vitamin E status. Methods: A total of 127 healthy people between the ages of 20 and 42 who underwent check-ups were randomly selected for the study. ELISA method measured the level of vitamin E. The effect of gender on vitamin E level was assessed, and RI was established using a parametric approach. Results: Women showed significantly higher levels of vitamin E than men (p = 0.01). The RI of vitamin E in people of childbearing age was 3.71 to 13.72, 4.52 to 14.64, and 4.17 to 13.52 mg/L, respectively, for the whole population, women and men. Conclusion: Using an ELISA method, this study established RI for vitamin E in the black Congolese population of childbearing age. We also found that women had significantly higher vitamin E levels than men. The results could provide a scientific basis for interpreting vitamin status in people of childbearing age in our setting.

Effect of Phosphorus on the Content of Vitamin E in Different Soybean Cultivars

[Objective] This study aimed to explore the effects of phosphorus on the contents of vitamin E in different cultivars of soybean grains and find the optimum application amount of phosphorus for different genotypes of soybean cultivars,in order to increase the contents of vitamin E in soybean grains and improve the qualities.[Method] Three soybean cultivars were selected as experimental materials,including Heinong 48（high-protein cultivar）,Heinong 37（intermediate cultivar） and Heinong 44（high-oil cultivar）.The soybeans were planted in pots,with 0.033 g/kg soil of N and K2O,four phosphorus treatments were set,respectively applied with 0（P1）,0.033（P2）,0.067（P3） and 0.100（P4） g/kg soil of P2O5,and the total contents of vitamin E in different cultivars of soybean grains were determined by high-performance liquid chromatography method.[Result] The total contents of vitamin E in the same cultivar of soybean grains in P3 treatment were significantly higher than that in the other three treatments,the total contents of vitamin E in Heinong 37,Heinong 44 and Heinong 48 in P3 treatment had increased by 11.96%,16.55% and 14.02%,compared with the control;among the three soybean cultivars in P2 treatment,the content of vitamin E in Heinong 37 was the maximum;among the 12 treatment combinations,the total contents of vitamin E in Heinong 44 in P3 treatment was the maximum.The contents of vitamin E in three soybean cultivars significantly varied among the various cultivars and different phosphorus treatments.[Conclusion] Application of phosphorus could affect the contents of vitamin E in three soybean cultivars,appropriate application amount of phosphorus is advantageous to improve the contents of vitamin E in soybean grains.

Enzyme-catalyzed Synthesis of Vitamin E Succinate Using a Chemically Modified Novozym-435

Vitamin E succinate was synthesized in organic solvents using a modified Novozym-435 as catalyst.In order to improve the catalytic performance of Novozym-435,the enzyme was modified using acetic anhydride, propionic anhydride and succinic anhydride separately.We found that both the hydrolytic activity and the thermal stability of the modified Novozym-435 were enhanced compared with the unmodified enzyme.The modified Novozym-435 catalysts were used to synthesize the succinate derivative of vitamin E.Compared with the native Novozym-435,the catalytic activity of the modified novozym-435 in promoting the synthesis of vitamin E succinate was dramatically increased,with the novozym-435 modified with succinic anhydride（N435-S）as the most active catalyst.Conditions for the synthesis of vitamin E succinate were also optimized.A mixture of tert-butanol and DMSO（volume ratio of 2︰3）was the most suitable medium for the reaction,whereas the appropriate molar ratio of vitamin E to succinic anhydride and reaction temperature were 1︰5 and 40°C,respectively.Under these reaction conditions,the yield of vitamin E succinate reached 94.4%.N435-S could be reused for five batches.

Effect of Copper and Zinc on Accumulation of Vitamin E in Wheat Embryo-derived Callus

[Objective] The aim was to study the effect of the content of copper and zinc on in medium the vitamin E accumulation in wheat embryo-dreived callus.[Method] The mathematical models were established to describe the growth kinetics and the vitamin E accumulation in wheat embryo callus cells.With the aim of getting the highest accumulation of the secondary metabolite Vitamin E,the optimal combination of copper and zinc in medium was confirmed by testing.[Result] The results showed that the production of vitamin E in B5 medium reached the highest value with 2.0 mg/mL ZnSO4·7H2O and 0.1 mg/mL CuSO4·5H2O.The fitting degrees of kinetic models of vitamin E accumulation and cell growth were 97.53% and 95.60%,respectively,which indicated good nonlinear relationships.[Conclusion] Both copper and zinc could affect the accumulation of vitamin E in wheat germ callus,and Copper showed more prominent effect than Zn.Synergism existed in low copper and zinc concentration,and the inhibitive effect enhanced with the increase of the concentrations.

Vitamin E in ataxia and neurodegenerative diseases:A review

Vitamin E is one of the most important lipid-soluble antioxidants. It is essential for the neurological function but its role in the central nervous system has not fully been elucidated. It is known that tocopherol acts in protecting cell membranes from oxidative damage and it can act as an anti-in?ammatory agent, which may also be neuroprotective, as well as regulating speci?c enzymes. There is growing evidence that oxidative stress plays a key role in the pathophysiology of several neurodegenerative disorders. These diseases are defined by the progressive loss of speci?c neuronal cell populations and are associated with protein aggregates. We reviewed some aspects related to the role of antioxidant properties of Vitamin E in preventing and/or curing neurodegenerative disorders such as the Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, ataxia, tardive dyskinesia and Huntington’s disease.

The protective effect of vitamin E against oxidative damage caused by formaldehyde in the testes of adult rats

Aim： To investigate the effect of formaldehyde （FA） on testes and the protective effect of vitamin E （VE） against oxidative damage by FA in the testes of adult rats. Methods： Thirty rats were randomly divided into three groups： （1） control; （2） FA treatment group （FAt）; and （3） FAt ＋ VE group. FAt and FAt ＋ VE groups were exposed to FA by inhalation at a concentration of 10 mg/m^3 for 2 weeks. In addition, FAt ＋ VE group were orally administered VE during the 2-week FA treatment. After the treatment, the histopathological and biochemical changes in testes, as well as the quantity and quality of sperm, were observed. Results： The testicular weight, the quantity and quality of sperm, the activities of superoxide dismutase （SOD）, glutathione peroxidase （GSH-Px） and glutathione （GSH） were significantly decreased whereas the level of malondialdehyde （MDA） was significantly increased in testes of rats in FAt group compared with those in the control group. VE treatment restored these parameters in FAt ＋ VE group. In addition, microscopy with hematoxylin-eosin （HE） staining showed that seminiferous tubules atrophied, seminiferous epithelial cells disintegrated and shed in rats in FAt group and VE treatment significantly improved the testicular structure in FAt ＋ VE group. Conclusion： FA destroys the testicular structure and function in adult rats by inducing oxidative stress, and this damage could be partially reversed by VE.

Radio-protective effect of vitamin E on spermatogenesis in mice exposed to γ-irradiation: a flow cytometric study

Aim: To investigate the effect of vitamin E on the radioprotection of spermatogenesis and chromatin condensation of spermatozoa during passage through the epididymis in mice exposed to irradiation. Methods: Adult outbred male ICR mice were orally administered natural vitamin E (VE, D-α-tocopheryl acetate) at 400 IU/kg for 7 days before exposure to 1 Gy of γ-irradiation. The animals were sacrificed at day 1, 7, 14, 21, 28, 35 and 70 post-irradiation (IR) and the percentage of testicular germ cells and epididymal sperm chromatin condensation was analyzed using flow cytometry. Results: Serum D-α-tocopheryl acetate levels were 47.4 ± 3.2 μg/dL in the treated group, yet it could not be detected in the control group. The testicular weight of irradiated mice pretreated with VE+IR was significantly (P<0.05) higher than that of those without VE treatment (IR) at day 14 and 21 post-irradiation. The percentage of primary spermatocytes (4C) in the VE+IR group was comparable to the controls but significantly (P<0.05) higher than those in the IR group from day 7 to 35 post-irradiation. The percentage of round spermatids (1C) in the VE+IR group was also significantly (P<0.05) higher than those in the IR group at day 28 post-irradiation. The primary spermatocytes : spermatogonia ratio in the IR group was significantly (P<0.05) declined at day 7 to 35 post-irradiation when compared to the VE+IR and control groups. The round spermatid : spermatogonia ratio in the VE+IR group was significantly (P<0.05) higher than that of the IR group at day 14 and 28 post-irradiation. The chromatin condensation of epididymal spermatozoa measured by propidium iodide uptake was not affected by 1 Gy of γ-irradiation. Conclusion: The administration of VE prior to irradiation protects spermatogenic cells from radiation.

Effects of dietary supplementation with vitamin E and selenium on rat hepatic stellate cell apoptosis

AIM： To evaluate the effects of dietary supplementation with vitamin E and selenium on proliferation and apoptosis of hepatic stellate cells （HSCs）, in acute liver injury induced by CCI4, and to explore their role in the recovery from hepatic fibrosis phase. METHODS： An acute liver damage model of rats was established by intraperitoneal injection of carbon tetrachloride （0.3 ml/100 g body weight） twice a week, then the rats were killed at 6, 24, 48, and 72 h after the first and third injection, respectively. A liver fibrosis model was established by the same injection for 8 wk. Then three rats were killed at 3, 7, 14, and 28 d after the last injection, respectively. The rats from the intervention group were fed with chow supplemented with vitamin E （250 mg/kg） and selenium （0.2 mg/kg）, and the rats in the normal control group and pathological group were given standard chow. Livers were harvested and stained with hematoxylin and eosin, Sirius red. Activated HSCs were determined by s-smooth muscle actin immunohistochemistry staining. Apoptotic HSCs were determined by dual staining with the terminal deoxynucleotidyl transferase UTP nick end labeling （TUNEL） and α-smooth muscle actin immunohistochemistry. Serum alanine aminotransferase and aspartate aminotransferase were also analyzed. RESULTS： In the acute liver damage model, the degree of liver injury was more serious in the pathological group than in the intervention group. At each time point, the number of activated HSCs was less in the intervention group than in the pathological group, while the number of apoptotic HSCs was more in the intervention group than in the pathological group. In the liver fibrosis model, the degree of liver fibrosis was more serious in the pathological group than in the intervention group. At each time point, the number of activated HSCs was less in the intervention group than in the pathological group, and the number of apoptotic HSCs was more in the intervention group than in the pathological group. CONCLUSION： Vitamin E and selenium supplementation at the given level can inhibit CCI4-induced activation and proliferation of HSCs and promote the apoptosis of activated HSCs in acute damage phase. Vitamin E and selenium can also effectively decrease the degree of hepatic fibrosis and promote the recovery process.

Effects of dietary vitamin E on muscle vitamin E and fatty acid content in Aohan fine-wool sheep

Background： Increasing the polyunsaturated fatty acid （PUFA） content and decreasing the saturated fatty acid （SFA） content of mutton can help to improve its nutritional value for consumers. Several laboratories have evaluated the effects of vitamin E on the fatty acid （FA） composition of muscle in sheep. However, little information is available on wool sheep, even though wool sheep breeds are an important source of mutton, especially in northern China where sheep are extensively farmed. The present study was designed to address the effects of vitamin E on muscle FA composition in male Aohan fine-wool sheep. Methods： Forty-two male Aohan fine-wool lambs （5 mo old） with similar initial body weight were randomly divided into seven groups and fed diets supplemented with 0 （control group）, 20, 100, 200, 1,000, 2,000, or 2,400 IU/sheep/d vitamin E for 12 mo. Three lambs from each group were slaughtered to measure vitamin E and FA content in the Iongissimus lumborum （LL） and gluteus medius （GM） muscles. Results： Vitamin E concentrations in the LL and GM increased significantly after 12 mo of vitamin E supplementation （P 〈 0.05）. However, this increase did not occur in a dose-dependent manner because the muscle vitamin E concentration was highest in the 200 IU/sheep/d group. Dietary vitamin E supplementation also caused a significant reduction in SFA content and an increase in monounsaturated FA （MUFA） content in the LL and GM （P 〈 0.05）. All six doses of vitamin E significantly increased cis9 tronsl -conjugated linoleic acid （cgtl -CLA） content in the LL compared with the control group （P 〈 0.05）. Conclusions： Dietary supplementation with vitamin E increased muscle vitamin E content and improved the nutritional value of mutton by decreasing SFA content and increasing MUFA and c9tl 1-CLA contents in Aohan fine-wool sheep. These effects were greatest in sheep fed a diet containing 200 IU/sheep/d vitamin E.

Growth performance,oxidative stress and immune status of newly weaned pigs fed peroxidized lipids with or without supplemental vitamin E or polyphenols

Background:This study evaluated the use of dietary vitamin E and polyphenols on growth,immune and oxidative status of weaned pigs fed peroxidized lipids.A total of 192 piglets(21 days of age and body weight of 6.62±1.04 kg)were assigned within sex and weight blocks to a 2×3 factorial arrangement using 48 pens with 4 pigs per pen.Dietary treatments consisted of lipid peroxidation(6%edible soybean oil or 6%peroxidized soybean oil),and antioxidant supplementation(control diet containing 33 IU/kg DL-α-tocopheryl-acetate;control with 200 IU/kg additional dl-α-tocopheryl-acetate;or control with 400 mg/kg polyphenols).Pigs were fed in 2 phases for 14 and 21 days,respectively.Results:Peroxidation of oil for 12 days at 80°C with exposure to 50 L/min of air substantially increased peroxide values,anisidine value,hexanal,and 2,4-decadienal concentrations.Feeding peroxidized lipids decreased(P<0.001)body weight(23.16 vs.18.74 kg),daily gain(473 vs.346 g/d),daily feed intake(658 vs.535 g/d)and gain:feed ratio(719 vs.647 g/kg).Lipid peroxidation decreased serum vitamin E(P<0.001)and this decrease was larger on day 35(1.82 vs.0.81 mg/kg)than day 14(1.95 vs.1.38 mg/kg).Supplemental vitamin E,but not polyphenols,increased(P≤0.002)serum vitamin E by 84%and 22%for control and peroxidized diets,respectively(interaction,P=0.001).Serum malondialdehyde decreased(P<0.001)with peroxidation on day 14,but not day 35 and protein carbonyl increased(P<0.001)with peroxidation on day 35,but not day 14.Serum 8-hydroxydeoxyguanosine was not affected(P>0.05).Total antioxidant capacity decreased with peroxidation(P<0.001)and increased with vitamin E(P=0.065)and polyphenols(P=0.046)for the control oil diet only.Serum cytokine concentrations increased with feeding peroxidized lipids on day 35,but were not affected by antioxidant supplementation(P>0.05).Conclusion:Feeding peroxidized lipids negatively impacted growth performance and antioxidant capacity of nursery pigs.Supplementation of vitamin E and polyphenols improved total antioxidant capacity,especially in pigs fed control diets,but did not restore growth performance.

Flow injection spectrophotometric determination of vitamin E in pharmaceuticals,milk powder and blood serum using potassium ferricyanide-Fe(Ⅲ) detection system

A simple and sensitive flow injection spectrophotometric method is reported for the determination of vitamin E using potassium ferricyanide-Fe(Ⅲ) detection system.In the presence of vitamin E,Fe(Ⅲ)/ferricyanide reduces.The in situ reduced ions are then reacted with unreduced portion of ferricyanide/Fe(Ⅲ) to make soluble Prussian blue,which is monitored at absorption wavelength of 735 nm.Linear calibration graph was obtained in the concentration range of 0.1-40μg mL^(-1).The relative standard deviations (n=4) were in the range of 1.1-3.6%,with limits of detection(3 s blank) of 0.04μg mL^(-1).The proposed method allowed 12 injections h^(-1).The method is applied to determine vitamin E in pharmaceuticals,infant milk and blood serum samples using hexane extraction with the recoveries in the range of 93±3 to 97.5±4%.The method is validated using certified reference materials SRM 968c for blood serum samples.

Antioxidants vitamin E and C attenuate hepatic fibrosis in biliary-obstructed rats

AIM： To investigate whether antioxidants vitamin E and C can retard development of hepatic fibrosis in the bilian/obstructed rats. METHODS： Fifty Wistar albino rats were randomly assigned to 5 groups （10 rats in each）. Bile duct was ligated in 40 rats and they were treated as follows： group vitC, vitamin C 10 mg/kg sc daily; group vitE, vitamin E 15 mg/kg sc daily; group vitEC, both of the vitamins; bile duct-ligated （BDL, control） group, physiological saline sc. The fifth group was assigned to sham operation. At the end of fourth week, the rats were decapitated, and hepatic tissue biochemical collagen content and collagen surface area were measured. Hepatic tissue specimens were histopathologically evaluated according to Scheuer system. Serum hyaluronate levels were measured by ELISA method. RESULTS： Despite being higher than sham group, hepatic collagen level was significantly decreased in each of the vitC, vitE and vitEC groups （32.7 ± 1.2, 33.8 ± 2.9, 36.7 ± 0.5 ）μg collagen/mg protein, respectively） compared to BDL （48.3 ± 0.6 mg collagen/g protein） （P 〈 0.001 for each vitamin group）. Each isolated vitamin C, isolated vitamin E and combined vitamin E/C supplementation prevented the increase in hepatic collagen surface density （7.0% ± 1.1%, 6.2% ± 1.7%, 12.3% ± 2.0%, respectively） compared to BDL （17.4% ± 5.6%） （P 〈 0.05 for each）. The same beneficial effect of vitamin C, vitamin E and combined vitamin E/C treatment was also observed on the decrease of serum hyaluronate levels compared to BDL group （P 〈 0.001）. The relative liver and spleen weights, serum transaminases, cholestatic enzymes, bilirubins and histopathological inflammation scores were not different between the antioxidant treatment groups and the control. However, fibrosis staging scores were obviously reduced only in the vitamin E/C combination group （vit EC： 2.4 ± 0.8 vs BDL： 3.1 ± 0.7; P 〈 0.05）. CONCLUSION： Each antioxidant vitamin E, vitamin C and their combination retard hepatic fibrosis in biliary-obstructed rats. Oxidative stress may play a role in the pathogenesis of hepatic fibrosis in secondary biliary cirrhosis.

Effect of vitamin E on oxidative stress status in small intestine of diabetic rat

AIM:To investigate the effect of vitamin E on oxidative stress status in the small intestine of diabetic rats. METHODS:Twenty-four male Wistar rats were randomly divided into three groups:Control (C),non-treated diabetic (NTD) and vitamin E-treated diabetic (VETD) groups. The increases in lipid peroxidation,protein oxidation and superoxide dismutase (SOD) in these three groups was compared after 6 wk. RESULTS:There was no significant difference in catalase activity between NTD and control rats. Compared to NTD rats,the treatment with vitamin E significantly decreased lipid peroxidation and protein oxidation,and also increased catalase activity and SOD. CONCLUSION:The results revealed the occurrence of oxidative stress in the small intestine of diabetic rats. Vitamin E,as an antioxidant,attenuates lipid peroxidation and protein oxidation,and increases antioxidant defense mechanism.

Effect of vitamin E on human sperm motility and lipid peroxidation in vitro

Aim: To assess the protective efficacy of vitamin E to counteract the reactive oxygen species (ROS) mediated damage onsperm motility, viability and lipid peroxidation. Methods: Human semen samples were obtained from the local hospi-tal. The split seminal fractions freed of seminal plasma were reconstituted in Ringer-Tyrode and subjected to varied vita-min E concentrations (0.1 - 2 mmol/L). Results: Dose-dependent improvement in both motility and viability accom-panied by concomitant decrease in malondialdehyde (MDA--an end product of lipid peroxidation) following vitamin Esupplementation was noticed. Conclusion: Vitamin E protects against the ROS mediated damage on spermatozoa.Vitamin E supplementation could be of clinical importance for prolonged spermatozoal storage whenever needed. (AsianJ Androl 1999 Sep; 1: 151 - 154 )