Ovarian Acid Research Articles

Variations in lipid composition of ovaries and hepatopancreas during vitellogenesis in the mud crab Scylla paramamosain: Implications of lipid transfer from hepatopancreas to ovaries

Lipid accumulation in ovaries is essential for reproductive success in decapods. Understanding of the mechanism of ovarian lipid accumulation is still in its infancy. In this study, we investigated lipid compositions of ovaries and hepatopancreas throughout vitellogenesis and hemolymph in the late-vitellogenic stage in the mud crab Scylla paramamosain. Total lipid content in ovaries consecutively increased from the early to late stage, and the main accumulated lipids were phosphatidylcholine (PC), alkenylglycerophosphoethanolamine (alkenyl-PE), triacylglycerol (TG), cholesteryl ester, and cholesterol. The lipid composition of hemolymph indicated that PC, alkenyl-PE, diacylglycerol (DG), ether DG, monoacylglycerol, and cholesterol were the main lipids transferred to ovaries from hepatopancreas. In hepatopancreas, the total lipid content appeared to increase during vitellogenesis and the late stage was significantly different from early and mid-stages. TG was the predominant lipid class that slightly decreased from the early to mid-stage, but dramatically increased in the late stage. In contrast, PC and alkenyl-PE significantly increased from the early to mid-stage and remained constantly in relatively low proportion until the late stage. These findings suggested PC and alkenyl-PE in the hepatopancreas likely play critical roles in regulating lipid transfer. Esterified fatty acids in ovaries and hepatopancreas were mainly C16:0, C18:0, 16:1, C18:1, C18:2, C20:4, C20:5, and C22:6, of which highly unsaturated fatty acids (HUFA) primarily occurred in alkenyl-PE and phosphatidylserine (PS) but not PC. In hemolymph, PC was abundant in HUFA besides of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA), while PS was predominantly composed of SFA and MUFA, implying a transformation of HUFA between phospholipids prior to transfer. These findings highlight the importance of phospholipid metabolism in the hepatopancreas to ovarian lipid accumulation. Our study provides novel insights into the mechanism of ovarian lipid accumulation in decapods.

Ovarian fullness affects biochemical composition and nutritional quality of female swimming crab Portunus trituberculatus

Ovary is an important edible component of female crabs in many countries, and ovarian fullness (maturity) had become an important quality indicator used for crab marketing. Adult females Portunus trituberculatus are typically divided into four grades (Grade I - Ⅳ) based on ovarian fullness in the carapace during the marketing. This study investigated the chemical composition and nutritional quality of market size female P. trituberculatus. The gonadosomatic index (GSI), hepatosomatic index (HSI) and total edible yield (TEY) showed a stepwise increase from Grade Ⅰ to Ⅳ (P < 0.05). Crude protein and total lipid content in both ovaries and muscle significantly increased with fullness, where Grade Ⅱ - Ⅳ had significantly higher lipid contents in the hepatopancreas compared to Grade Ⅰ. Redness (a*) of carapace and ovaries was consistent with the total carotenoid contents in tissues. Σ MUFA in both ovaries and muscle increased with crab grade, while Σ PUFA in ovaries and muscle, as well as Σ MUFA in the hepatopancreas decreased. For most amino acids in ovaries and muscle were also found to increase with grade. Higher-graded females generally had higher TEY, color parameters and better nutritional quality in edible tissues than the Grade I and II, which appears related to their different ovary stages of P. trituberculatus.

Effects of Dietary Omega-3 Fatty Acids (DHA/EPA) and Vitamin E on Fatty Acid Profile of Common Carp, Cyprinus carpio Ovaries

The current study aimed to clarify the fatty acids profile in the breeding stock ovaries of common carp (Cyprinus carpio L.) fed on two food additives. The study was carried out in the Shrimp Hatchery which belonging to the Basrah Agricultural Directorate. Three treatment groups were used, the first treatment (T1) represented as control without any food additives, the second treatment (T2) supplemented with 5 g/kg omega-3 fatty acids, and the third treatment (T3) to which vitamin E was added at a concentration of 200 mg/kg. Fishes were randomly distributed in three replicates for each treatment with six of common carp brood stock per replicate. Nine cages were used which placed in earthen pond. Feeding trail lasted from 29 Oct 2018 to 14 Mar 2019. After feeding fish for 82 days, the oil was extracted from gonads by two methods, the first one by Soxhlet apparatus and the second by Accelerated Solvent Extraction (ASE) method. The fatty acid profiles were analyzed using gas chromatograph by GC/MS (Gas Chromatography Mass spectrometry). Results showed that the content of fatty acids in the ovaries of treated fishes in T1, the presence of saturated and unsaturated omega-3 and omega-6 fatty acids, were monounsaturated fatty acid (C19H36:1) scored the highest percentage (52.55%). Fishes in T2 recorded the presence of saturated and unsaturated omega-3 and omega-6 fatty acids were omega-12 (C18H34:12) recorded the highest percentage (50.02%), while T3 fishes showed the presence of saturated and unsaturated fatty acids from the group of omega-6 fatty acids and the unsaturated fatty acid omega-9 (C18H34:9) record the highest percentage (63.24%).In conclusion this study suggested that the content of fatty acids in fish ovaries reflects the composition of fatty acids in the diet.

Diverse Odd-Chain Monoenoic Fatty Acids and Novel Non-Methylene-Interrupted Heptadecadienoic Acids in Ovaries of the Limpet Cellana toreuma.

Highly diverse dienoic fatty acids (FA), especially non-methylene-interrupted (NMI) FA, have been recognized in triacylglycerols (TAG) and polar lipids of ovaries of the limpet Cellana toreuma. To gain additional insights into the structural diversity of FA in ovaries, this study aimed to clarify previously undescribed minor monoenoic FA isomers and unidentified minor NMI FA by combined argentation thin-layer chromatography (TLC) and gas chromatography-mass spectrometry (GC-MS) of their 3-pyridylcarbinol derivatives. A total 66 monoenoic FA from C14 to C22, including 12 branched-chain FA, were identified. A surprising finding was a series of 13 heptadecenoic acids with double bonds at either Δ5, Δ6, Δ7, Δ8, Δ9, Δ10, Δ11, Δ12, Δ13, Δ15, or Δ16 positions. Besides previously identified NMI FA, 7,18-nonadecadienoic (19:2Δ7,18), 9,18-nonadecadienoic (19:2Δ9,18), 11,18-nonadecadienoic (19:2Δ11,18), 7,20-heneicosadienoic (21:2Δ7,20), and 11,20-heneicosadienoic (21:2Δ11,20) acids, two novel related NMI FA, 5,16-heptadecadienoic (17:2Δ5,16) and 7,16-heptadecadienoic (17:2Δ7,16) acids, were found in TAG. These findings could provide new insights into clarifying the biological characteristics of marine NMI FA.

Total Synthesis and Structural Elucidation of Two Unusual Non-Methylene-Interrupted Fatty Acids in Ovaries of the Limpet Cellana toreuma.

In our previous study, unusual odd-numbered dienoic acids with a terminal olefin were found as minor components in ovaries of the Japanese limpet Cellana toreuma, and the synthetic interests have been focused onto their structural confirmation and the inspection into their potential biological activity. Here, we describe an efficient and stereoselective total synthesis of two new unusual dienoic acids, 19:2∆7,18 and 21:2∆7,20, through a common pathway involving the strategic combination of alkyne-zipper reaction and Lindlar hydrogenation for the construction of their unique carbon chains. In our synthetic study, 2-propyn-1-ol was at first subjected to alkylation and alkyne-zipper reaction to form the two fragments, and the subsequent carbon chain elongation was achieved by the usual coupling reaction to obtain the C-19 and C-21 products bearing an internal acetylenic group. Then, the internal acetylenic group of these products was subjected to Lindlar hydrogenation to form a Z-alkenyl moiety, and the subsequent deprotection of the products was carried out under an acidic condition without isomerization of the internal Z-alkenyl group. Total synthesis of target fatty acids, 19:2∆7,18 and 21:2∆7,20, was finally accomplished by two-step oxidation of the resulting alcohols into carboxylic acids in a highly chemoselective manner, and the structures of these unusual natural fatty acids were finally elucidated by identifying the GC-MS spectra of the methyl esters of authentic and synthetic fatty acids.

An Unprecedented Occurrence of Δ5,9- and Δ9,15-Dienoic Fatty Acids in Ovaries of the Archaeogastropod Limpet Cellana toreuma.

A detailed structural diversity of dienoic fatty acids (FA), including non-methylene-interrupted dienoic FA, of triacylglycerols and polar lipids in ovaries of Cellana toreuma was clarified for the first time by using capillary gas chromatography-mass spectrometry of their 3-pyridylcarbinol esters and argentation thin-layer chromatography. Interestingly, in addition to 5,9-octadecadienoic (18:2Δ5,9), 5,9-eicosadienoic (20:2Δ5,9), 5,9-heneicosadienoic (21:2Δ5,9), 5,9-docosadienoic (22:2Δ5,9), 5,9-tricosadienoic (23:2Δ5,9), and 5,9-tetracosadienoic (24:2Δ5,9) acids, previously identified in ovaries of C. grata, rare FA 5,9-hexadecadienoic (16:2Δ5,9), 5,9-nonadecadienoic (19:2Δ5,9), and 21-methyl-5,9-docosadienoic (iso 23:2Δ5,9) were newly recognized in ovaries of C. toreuma. Detectable amounts of four Δ9,15-dienoic FA were present in the ovary lipids. The FA identified were one novel 9,15-heneicosadienoic (21:2Δ9,15) acid and known 9,15-docosadienoic (22:2Δ9,15), 9,15-tricosadienoic (23:2Δ9,15), and 9,15-tetracosadienoic (24:2Δ9,15) acids. The findings help to explain the broad evidence of the structural diversity in marine gastropods and suggest biomarkers to evaluate marine food web relations.

Histological analysis of acute toxicity of 2,4-diclorophenoxy acetic acid in ovary of zebrafish

Plant growth regulators are the chemicals that are found in plants and produced synthetically. In agricultural applications, plant hormones are used in minor quantities for fixing the problems. In our research, we studied the effects of 2,4 diclorophenoxyacetic acid (2,4D), which is an auxin used in agricultural applications. Auxins are the group that are used most popularly in plant growth regulators. In our study, different doses of 2,4 diclorophenoxyacetic acid are given to zebrafish, and ovarium tissues are observed histomorphologically. We generated one control and three experiment groups from the stock solution. The experiment was carried out in 20 liter capacity complete glass aquarium at 24±1°C water temperature. After five days of application, fishes were dissected. Histomorphological changes of the ovarium were investigated under a light microscope. A decrease in the number of oocytes in zebrafish ovarium was observed when compared with the control group. Many deformed and underdeveloped oocytes were detected. An increase in the number of atretic oocytes was observed. It was deduced that acute doses of 2,4 diclorophenoxyacetic acid decelerates oogenesis in fishes.

Lipid content and fatty acid composition in wild-caught silver pomfret ( Pampus argenteus) broodstocks: Effects on gonad development

The fatty acid reserves of broodstocks profoundly affect the fecundity of spawners as well as the quality of the newly hatched larvae. Investigation of the lipid and fatty acid changes in wild-caught broodstocks during the reproductive season should elucidate the most effective strategy with which to enrich broodstocks in artificial breeding programs. This paper investigated the lipid and fatty acid compositions of wild broodstocks of silver pomfret, Pampus argenteus, caught at the Zhoushan fishery ground during the reproductive season. The results indicated that there were significant differences in lipid content among gonad, muscle and liver; mean lipid levels in ovary, testis, liver and muscle were 41.85%, 18.54%, 27.80% and 32.31%, respectively. The lipid content in gonads at developmental stages III–V was relatively more stable than that in muscle or liver, although the lipid level increased in ovary and decreased in muscle as the female broodstocks developed from phase III to phase V. There were significant differences in fatty acid levels among broodstock ovary, testis, muscle and liver. The dominant fatty acids in ovary were as follows: 18:1n−9 (16.91%) > DHA (docosahexaenoic acid) (15.46%) > 16:4n−3 (13.14%) > 16:0 (12.65%) > EPA (eicosapentaenoic acid) (6.46%) > 16:1 (5.34%). In female broodstock liver and muscle, the dominant fatty acids were 16:0 (36.42%) > 18:1n−9 (23.26%) > 18:0 (7.50%) > 16:1 (6.98%) > 14:0 (5.10%) > DHA (4.98%) and 18:1n−9 (26.35%) > 16:0 (24.07%) > DHA (8.38%) > 16:1 (6.62%) > 18:0 (5.48%) > 14:0(4.44%), respectively. The dominant fatty acids in testis were as follows: DHA (29.84%) > 16:0 (23.93%) > 18:1n−9 (8.78%) > 18:0 (7.98%) > EPA (7.96%) > ARA (arachidonic acid) (3.24%). In the liver and muscle of male broodstocks, the dominant fatty acids were 16:0 (30.14%) > 18:1n−9 (25.54%) > 18:0 (8.24%) > 16:1 (7.24%) > 14:0 (5.20%) > DHA (4.75%) and 18:1n−9 (29.51%) > 16:0 (23.90%) > DHA (7.80%) > 18:0 (6.34%) > 16:1 (6.22%) > 14:0(3.88%), respectively. The n−3PUFAs and n−3/n−6 ratios in ovary and testis of the broodstocks were significant higher than those in the liver and muscle of the broodstocks. The changes in fatty acid composition in ovary and testis as the broodstocks developed from phase III to phase V were smaller in magnitude than those in muscle or liver. It is therefore suggested that the lipid preferentially transferred to ovary from muscle during the reproductive season, and the PUFAs, such as DHA, EPA, 16:4n−3 and ARA, were selectively transferred to, and conserved in, the ovaries of silver pomfret broodstocks.

Selective accumulation of mycosporine-like amino acids in ovaries of the green sea urchin Strongylocentrotus droebachiensis is not affected by ultraviolet radiation

Field sampling and laboratory experiments examined whether ultraviolet radiation (UVR) affects the reproduction or the accumulation of mycosporine-like amino acids (MAAs) and ascorbic acid in ovaries of the green sea urchin Strongylocentrotus droebachiensis (Muller). Ovaries of sea urchins sampled across a depth gradient (0.5–10 m) in March 1998 did not differ in their gonadal index, or in concentrations of MAAs, or ascorbic acid. Concentrations of MAAs and ascorbic acid in ovaries were higher in sea urchins collected from a kelp bed compared with those collected from a community of crustose coralline algae. The concentrations of MAAs in ovaries varied seasonally, peaking in March, when sea urchins had high gonadal indices just before spawning. Ovaries of sea urchins maintained on controlled diets from October 1997 to April 1998 accumulated significantly higher concentrations of MAAs when fed a diet rich in MAAs than did ovaries of sea urchins fed an alga lacking MAAs, but the gonadal indices did not differ between diets. Sea urchins accumulated principally one MAA, shinorine, but not others that were available in high concentrations in their diet. Neither the gonadal index nor the ovarian concentrations of MAAs were affected by daily exposure of adult urchins to UVR for 6 months. Concentrations of ascorbic acid in ovaries did not differ among diets or UV-treatments. The percentages of nutritive phagocytes and gametic cells were not affected by diet or UVR, and did not co-vary with concentrations of MAAs or ascorbic acid in ovaries. These data support previous demonstrations that female sea urchins accumulate MAAs from their diet of macroalgae, but further show that the accumulation is selective for specific MAAs, particularly shinorine, and that adult S. droebachiensis do not accumulate MAAs in their ovaries or eggs in response to UV-exposure. These are also the first experimental studies to address whether MAAs are affected by or regulate gametogenesis, and indicate that they do not.

The dynamics of gonad growth and ascorbate status in yellow perch, Perca flavescens (Mitchill)

Yellow perch, Perca flavescens (Mitchill), caught in the wild (Grand St Marys Lake, Ohio) and cultured in the laboratory were used to examine the relationship between gonad development and the concentration of ascorbic acid in ovaries, testes, liver and kidney. In wild fish the ovary had concentrations of ascorbate twice as high (75-102 μg g-1) as the testis (28-48 μg g-1), and when the differences in gonadosomatic indices between sexes were accounted for, females deposited 10-fold more of this essential nutrient in gonads than did males. Yellow perch cultured intensively throughout the gonadal recrudescence had shown a decrease of ascorbate concentration in the kidney, liver and ovary during winter, most likely due to the low dietary level of the vitamin. Diet enrichment with ascorbic acid resulted in a dramatic increase of ascorbate in ovary and other tissues. Incorporation of ascorbic acid may take place during the late vitellogenesis, and this vitamin deserves to be studied as a quality indicator in fish eggs.

Variation in the lipid content of wild-caught females of the marine shrimpPenaeus kerathurus during sexual maturation

Changes in total lipids, lipid classes and their fatty acid contents were studied in the ovaries and midgut glands ofPenaeus kerathurus Forskal females during sexual maturation. The shrimp were captured in the Gulf of Cadiz (southwest Spain) in 1990. The lipid content and fatty acids, in relative terms, increased during ovarian development. The greatest changes occurred between Maturation Stages III and IV. Ovarian lipids were dominated by polar classes, whereas in the midgut gland the major classes were triacylglycerols and sterol esters. The amounts of major fatty acids in ovaries (16:0, 16:1n-7, 18:1n-9, 18:1n-7, 20:5n-3 and 22:6n-3) increased with increasing maturity, but declined slightly between Stages III and IV. The total polar lipid content of the midgut was 5.7% (by dry weight) and its fatty acid composition remained constant during the whole study period. Total lipid content of the midgut gland showed an upward trend during sexual maturation, except between Stages II and III, when a slight decrease was observed. Predominant fatty acids in the midgut gland (16:1n-7, 20:5n-3 and 22:6n-3) displayed a noteworthy decline between Stages II and III, corresponding with the marked increase in total lipid fatty acid content in the ovaries during the same period.

Fluorescence high-performance liquid chromatography of arachidonic, eicosapentaenoic and some other higher fatty acids in ovary of several fishes

A highly sensitive and selective fluorescence high-performance liquid chromatography using 9-anthryl-diazomethane as a pre-labelling reagent was applied to the simultaneous microanalysis of arachidonic and eicosapentaenoic acids, and some other higher fatty acids at nanogram level in ovary of several tropical adult fishes taken at Rabaul of New Britain. An existing tendency of arachidonic and eicosapentaenoic acids as precursor of prostaglandins in the generative organ of the fishes, has been revealed.

Transport of gonadotropin to various organs and its effect on protein synthesis in the ovary

131I-gonadotropin投与実験により, 投与したgonadotropinは1時間以内に急速に血中より消退し, それ以後は比較的ゆるやかに消退した.また, 卵巣への集積傾向は認められなかつた.一方, HCG投与後, 卵巣での蛋白質, 核酸合成は促進され, このRNA, 蛋白合成の促進効果はactinomycin D投与により阻止された.したがつてHCGの蛋白合成促進効果は少くともその-部はtranscription の段階で制御されているものと思われる.