Retinol-deficient rats can convert a pharmacological dose of astaxanthin to retinol: antioxidant potential of astaxanthin, lutein, and β-carotene

2010 ◽  
Vol 88 (10) ◽  
pp. 977-985 ◽  
Author(s):  
R. K. Sangeetha ◽  
V. Baskaran

Retinol (ROH) and provitamin-A carotenoids are recommended to treat ROH deficiency. Xanthophyll carotenoids, being potent antioxidants, can modulate health disorders. We hypothesize that nonprovitamin-A carotenoids may yield ROH and suppress lipid peroxidation under ROH deficiency. This study aimed to (i) study the possible bioconversion of astaxanthin and lutein to ROH similar to β-carotene and (ii) determine the antioxidant potential of these carotenoids with reference to Na+/K+-ATPase, antioxidant molecules, and lipid peroxidation (Lpx) induced by ROH deficiency in rats. ROH deficiency was induced in rats (n = 5 per group) by feeding a diet devoid of ROH. Retinol-deficient (RD) rats were gavaged with astaxanthin, lutein, β-carotene, or peanut oil alone (RD group) for 7 days. Results show that the RD group had lowered plasma ROH levels (0.3 µmol/L), whereas ROH rose in astaxanthin and β-carotene groups (4.9 and 5.7 µmol/L, respectively), which was supported by enhanced (69% and 70%) intestinal β-carotene 15,15′-monooxygenase activity. Astaxanthin, lutein, and β-carotene lowered Lpx by 45%, 41%, and 40% (plasma), respectively, and 59%, 64%, and 60% (liver), respectively, compared with the RD group. Lowered Na+/K+-ATPase and enhanced superoxide dismutase, catalase, and glutathione-S-transferase activities support the lowered Lpx. To conclude, this report confirms that astaxanthin is converted into β-carotene and ROH in ROH-deficient rats, and the antioxidant potential of carotenoids was in the order astaxanthin > lutein > β-carotene.

2014 ◽  
Vol 84 (Supplement 1) ◽  
pp. 25-29 ◽  
Author(s):  
Guangwen Tang

Humans need vitamin A and obtain essential vitamin A by conversion of plant foods rich in provitamin A and/or absorption of preformed vitamin A from foods of animal origin. The determination of the vitamin A value of plant foods rich in provitamin A is important but has challenges. The aim of this paper is to review the progress over last 80 years following the discovery on the conversion of β-carotene to vitamin A and the various techniques including stable isotope technologies that have been developed to determine vitamin A values of plant provitamin A (mainly β-carotene). These include applications from using radioactive β-carotene and vitamin A, depletion-repletion with vitamin A and β-carotene, and measuring postprandial chylomicron fractions after feeding a β-carotene rich diet, to using stable isotopes as tracers to follow the absorption and conversion of plant food provitamin A carotenoids (mainly β-carotene) in humans. These approaches have greatly promoted our understanding of the absorption and conversion of β-carotene to vitamin A. Stable isotope labeled plant foods are useful for determining the overall bioavailability of provitamin A carotenoids from specific foods. Locally obtained plant foods can provide vitamin A and prevent deficiency of vitamin A, a remaining worldwide concern.


2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Israel Pérez-Torres ◽  
Verónica Guarner-Lans ◽  
Alejandra Zúñiga-Muñoz ◽  
Rodrigo Velázquez Espejel ◽  
Alfredo Cabrera-Orefice ◽  
...  

We report the effect of cross-sex hormonal replacement on antioxidant enzymes from rat retroperitoneal fat adipocytes. Eight rats of each gender were assigned to each of the following groups: control groups were intact female or male (F and M, resp.). Experimental groups were ovariectomized F (OvxF), castrated M (CasM), OvxF plus testosterone (OvxF + T), and CasM plus estradiol (CasM + E2) groups. After sacrifice, retroperitoneal fat was dissected and processed for histology. Adipocytes were isolated and the following enzymatic activities were determined: Cu-Zn superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and glutathione reductase (GR). Also, glutathione (GSH) and lipid peroxidation (LPO) were measured. In OvxF, retroperitoneal fat increased and adipocytes were enlarged, while in CasM rats a decrease in retroperitoneal fat and small adipocytes are observed. The cross-sex hormonal replacement in F rats was associated with larger adipocytes and a further decreased activity of Cu-Zn SOD, CAT, GPx, GST, GR, and GSH, in addition to an increase in LPO. CasM + E2exhibited the opposite effects showing further activation antioxidant enzymes and decreases in LPO. In conclusion, E2deficiency favors an increase in retroperitoneal fat and large adipocytes. Cross-sex hormonal replacement in F rats aggravates the condition by inhibiting antioxidant enzymes.


Plants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 541 ◽  
Author(s):  
Beloved Mensah Dzomeku ◽  
Julian P. Wald ◽  
Jens Norbert Wünsche ◽  
Donatus Nohr ◽  
Hans K. Biesalski

Diet diversification and the exploitation of traditional, micronutrient-rich germplasm of staple crops are generally regarded as sustainable and low-cost approaches to increase the micronutrient intake of resource-poor people. Sun’s UV index was collected daily throughout the year. The study assessed the seasonality of provitamin A carotenoids in three plantain cultivars in response to climatic condition. Fruits were harvested at three maturities and freeze-dried before analysis. The results showed that there were high levels of the sun’s UV-B radiations throughout the year with the highest occurring from November to May when the area experienced clear skies with minimal cloud cover. These high levels of the sun’s UV-B index occurred between 9.00 h GMT and 17.00 h GMT. The study also showed that α-carotene content increased with maturity in “Apantu” during the rainy seasons ranging from 95 to 172 μg/100 g of dry pulp. Similar trends were observed during the dry season with a range of 28 to 489 μg/100 g. The α-carotene contents were very high in the periods of high sun’s UV-B radiations compared to the periods of low sun’s UV-B radiations. The α-carotene levels in the giant French plantains showed similar trends. Intermediate French “Oniaba” and False Horn “Apantu” plantain cultivar showed the highest content of β-carotene during the dry season. The high provitamin A carotenoid levels in the cultivars coincided with the high levels of the sun’s UV index.


2003 ◽  
Vol 89 (6) ◽  
pp. 787-793 ◽  
Author(s):  
Antonio Pérez-Gálvez ◽  
Hans D. Martin ◽  
Helmut Sies ◽  
Wilhelm Stahl

The intake of a carotenoid-rich diet is epidemiologically related to a lower risk for different chronic disorders like cardiovascular disease, some types of cancer or age-related macular degeneration. Red pepper (Capsicum annuumL.) and its dietary products contain a variety of carotenoids, which may contribute to the carotenoid pattern of human blood and tissues. The objective of the present study was to assess the availability of carotenoids from paprika oleoresin, including zeaxanthin, β-cryptoxanthin, β-carotene and the paprika-specific oxocarotenoids capsanthin and capsorubin. After overnight fasting, the volunteers (n9) ingested a single dose of the paprika oleoresin containing 6·4 mg zeaxanthin, 4·2 mg β-cryptoxanthin, 6·2 mg β-carotene, 35·0 mg capsanthin and 2·0 mg capsorubin. At different time points the carotenoid pattern in the chylomicron fraction was analysed to evaluate carotenoid absorption. From the major carotenoids present in the paprika oleoresin only zeaxanthin, β-cryptoxanthin and β-carotene were detectable in considerable amounts. Although the xanthophylls in paprika oleoresin were mainly present as mono- or di-esters, only free zeaxanthin and β-cryptoxanthin were found in human samples. The bioavailability of the pepper-specific carotenoids capsanthin and capsorubin from paprika oleoresin is very low. However, oleoresin is a suitable source for the provitamin A carotenoids β-carotene and β-cryptoxanthin and the macular pigment zeaxanthin.


Antioxidants ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 484
Author(s):  
Elena Rodríguez-Rodríguez ◽  
Beatriz Beltrán-de-Miguel ◽  
Kerly X. Samaniego-Aguilar ◽  
Milagros Sánchez-Prieto ◽  
Rocío Estévez-Santiago ◽  
...  

Carotenoids are bioactive compounds with widely accepted health benefits. Their quantification in human faeces can be a useful non-invasive approach to assess their bioavailability. Identification and quantification of major dietary carotenoids in human faeces was the aim of the present study. Faeces and dietary intake were obtained from 101 healthy adults (45–65 years). Carotenoid concentrations were determined by HPLC in faeces and by 3-day food records in dietary intake. Carotenoids quantified in faeces (μg/g dry weight, median) were: β-carotene (39.5), lycopene (20), lutein (17.5), phytoene (11.4), zeaxanthin (6.3), β-cryptoxanthin (4.5), phytofluene (2.9). α-carotene (5.3) and violaxanthin were found 75.5% and 7.1% of the faeces. The carotenoids found in the highest concentrations corresponded to the ones consumed in the greatest amounts (μg/d): lycopene (13,146), phytoene (2697), β-carotene (1812), lutein+zeaxanthin (1148). Carotenoid concentration in faeces and in dietary intake showed correlation for the total non-provitamin A carotenoids (r = 0.302; p = 0.003), phytoene (r = 0.339; p = 0.001), phytofluene (r = 0.279; p = 0.005), lycopene (0.223; p = 0.027), lutein+zeaxanthin (r = 0.291; p = 0.04) and β-cryptoxanthin (r = 0.323; p = 0.001). A high proportion of dietary carotenoids, especially those with provitamin A activity and some of their isomers, reach the large intestine, suggesting a low bioavailability of their intact forms.


2007 ◽  
Vol 55 (26) ◽  
pp. 10744-10750 ◽  
Author(s):  
Shanshan Li ◽  
Francis A. K. Tayie ◽  
Melissa F. Young ◽  
Torbert Rocheford ◽  
Wendy S. White

Author(s):  
Udedi Stanley Chidi ◽  
Ani Onuabuchi Nnenna ◽  
Asogwa Kingsley Kelechi ◽  
Maduji Fitzcharles Chijindu ◽  
Okafor Clinton Nebolisa

This study investigated the in-vitro antioxidant activity of ethanol leaf extract of Justicia carnea and its effect on antioxidant status of alloxan-induced diabetic albino rats. The in-vitro antioxidant activity was assayed by determining the total phenol, flavonoids, ascorbic acid, β-carotene and lycopene contents and by using 2,2 diphenyl-1-picrylhydrazyl (DPPH) radical, reducing antioxidant power and inhibition of lipid peroxidation antioxidant systems. Oxidative stress was produced in rats by single intraperitoneal injection of 150 mg/kg alloxan and serum concentration of malonaldehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) were determined. Five experimental groups of rats (n=6) were used for the study. Two groups of diabetic rats received oral daily doses of 100 and 200 mg/kg Justicia carnea leaf extract respectively while gilbenclamide (5 mg/ml); a standard diabetic drug was also given to a specific group for 14 days. From the result, the leaf extract contained a higher concentration of flavonoids followed byphenols, ascorbic acid, lycopene and β-carotene. The extract displayed more potent reducing power ability with EC50 of 40 µg/ml compared to BHA (EC50 of 400µg/ml). The percentage DPPH radical scavenging activity of the extract was also higher with EC50 of 200µg/ml and increased with increase in concentration while BHA had EC50of 320µg/ml. The inhibition of lipid peroxidation also increased with increase in concentration with EC50 of 58µg/ml and comparable with BHA (EC50=60µg/ml). The effect of the plant extract on antioxidant enzyme activities was concentration-dependent. Administration of 100mg/kg of the plant extract resulted in a significant decrease (p<0.05) in serum MDA concentration, while 200 mg/kg of the extract caused a significant (p˂0.05) increase in superoxide dismutase (SOD) and catalase activities with a non-significant increase (p>0.05) in the serum level of MDA when compared with the diabetic untreated group. These findings suggest that ethanol leaf extract of Justicia carnea have antioxidant properties and could handle diabetes-induced oxidative stress.


2022 ◽  
Vol 20 (4) ◽  
pp. 63-70
Author(s):  
O. V. Smirnova ◽  
V. V. Tsukanov ◽  
A. A. Sinyakov ◽  
O. L. Moskalenko ◽  
N. G. Elmanova ◽  
...  

Background. The problem of gastric cancer remains unresolved throughout the world, while chronic atrophic gastritis (CAG) increases the likelihood of its development by 15 times. In the Russian Federation, the incidence of gastric cancer (GC) is among the highest, with it prevailing among males. One of the leading mechanisms in molecular pathology of membranes is lipid peroxidation (LPO). The severity of oxidative membrane damage depends on concomitant diseases, contributing to emergence and progression of pathological processes and development of cancer. Currently, the problem of LPO is unsolved in biological systems.The aim of this study was to investigate the state of LPO and antioxidant defense system in CAG and GC. Materials and methods. The parameters were studied in 45 patients with CAG and 50 patients with GC. The control group included 50 practically healthy volunteers without gastrointestinal complaints, who did not have changes in the gastric mucosa according to the fibroesophagogastroduodenoscopy (FEGDS) findings.Results. In patients with CAG, an increase in malondialdehyde, superoxide dismutase, catalase, glutathione S-transferase, and glutathione peroxidase was found in the blood plasma compared with the control group. In patients with CAG, lipid peroxidation was activated, and the malondialdehyde level increased by 3.5 times relative to normal values. At the same time, the body fought against oxidative stress by increasing the activity of antioxidant enzymes, such as superoxide dismutase, catalase, glutathione S-transferase, and glutathione peroxidase. All patients with GC showed pronounced oxidative stress in the blood plasma in the form of a 45-fold increase in malondialdehyde. The activity of the main antioxidant enzyme superoxide dismutase was reduced in GC. Catalase was activated, which indicated pronounced oxidative stress, significant damage to blood vessels, and massive cell death. Glutathione-related enzymes (glutathione S-transferase and glutathione peroxidase) and the antioxidant protein ceruloplasmin were activated, which also indicated significant oxidative stress and severe intoxication in patients with GC.Conclusion. Depending on the stage and type of cancer, an in-depth study of lipid peroxidation and factors of the antioxidant defense system can be used to correct therapy and prevent cancer and can serve as markers of progression and prognosis in gastric cancer. 


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