Relativein vitro effectiveness of estradiol-17β, androgens, corticosteroids, progesterone and other pregnene derivatives on germinal vesicle breakdown in oocytes of Indian major carps,Labeo rohita, Cirrhinus mrigala andCatla catla

August 15, 2017 | Autor: R.moses Inbaraj | Categoria: Ecology, Fisheries Sciences, Oocyte Maturation, Dehydroepiandrosterone, Fish Physiology and Biochemistry
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Fish Physiologyand Biochemistryvol. 6 no. 5 pp 289-295 (1989) Kugler Publications, Amsterdam/Berkeley

Relative in vitro effectiveness of estradiol-17/3, androgens, corticosteroids, progesterone and other pregnene derivatives on germinal vesicle breakdown in oocytes of Indian major carps, Labeo rohita, Cirrhinus mrigala and Catla catla S. Haider and R. Moses Inbaraj

Centre o f Advanced Study in Zoology, Banaras Hindu University, Varanasi - 221005, India

Keywords: germinal vesicle breakdown, oocyte, Indian major carps, effectiveness of steroids

Abstract

The relative effectiveness of estradiol-17~, androgens, corticosteroids, progesterone and other pregnene derivatives on germinal vesicle breakdown (GVBD) was investigated in vitro using folliculated oocytes of three carps, Labeo rohita, Cirrhinus mrigala, and Catla catla. In all three species progesterone and 17~hydroxyprogesterone could induce GVBD but relatively 17a,20~-dihydroxyprogesterone was consistently found to be the most potent maturation-inducing steroid. Both estradiol-17~ and testosterone were ineffective in inducing GVBD. Androsterone and dehydroepiandrosterone were found to be effective in C. carla at all the concentrations used. Deoxycorticosterone (DOC), hydrocortisone (HC) and cortisone were effective inducer of GVBD in C. catla whereas in L. rohita and C. mrigala only cortisone was found to be effective. All 5/3-reduced pregnenes were effective in inducing GVBD in L. rohita but in C. carla, only 5~3-pregnane17~-01-3,20-dione and 5~3-pregnane-3c~, 17a,2013-triol and in C. mrigala, 5~-pregnane-3a-ol-20- one could induce oocyte maturation.

Introduction

In most vertebrates, including fishes, meiotic activity in primary oocyte is arrested at the diplotene stage of first prophase which is followed by an enlargement of the nucleus (germinal vesicle (GV)) and cytoplasmic growth. At the end of cytoplasmic growth phase i.e. vitellogenesis, the meiotic activity of primary oocyte has to be resumed before the oocyte is capable of being fertilized. Resumption of meiotic activity is known as oocyte maturation. In fishes it is generally accepted that the preovulatory surge of gonadotropin stimulates oocytes to resume their first meiotic division which consists of the breakdown of the germinal vesicle (GVBD), chromosome condensation, and extrusion of the first polar body (Masui and Clarke 1979). In most

teleosts gonadotropin-induced oocyte maturation is mediated through the production of maturationinducing steroid (MIS) by the follicular layer o( each oocytes (Masui and Clarke 1979; Goetz 1983). However, the nature of MIS produced by ovarian follicular tissues in teleosts has not yet been conclusively determined. Several in vivo and in vitro studies have shown that progesterone (Goswami and Sundararaj 1974; Wallace and Selman 1978), 17ct-hydroxyprogesterone (17o~-OHprog), 17a,20/3-dihydroxy-4- pregnen-3-one (17c~,20/3-diOHprog) (Jalabert 1976; Nagahama et al. 1983; Upadhyaya and Haider 1986), 20/3-hydroxy-dehydroprogesterone (Sower and Schreck 1982) and pregnenelone (Iwamatsu 1978) are highly effective steroids in inducing GVBD in several species of teleosts. Among

290 these, 17o~,20B-diOHprog is found to be the most potent inducer of oocyte maturation and is considered to be the natural, MIS in amago salmon (Nagahama and Adachi 1985) and in tropical catfish (Suzuki et al. 1987). Nagahama et al. (1983) have found that 5/~-reduced pregnenes play a major role in the metabolism of 17a,20/3-OHprog and have suggested that these 5~3-reduced pregnenes may be involved in controlling oocyte maturation in salmonids. However, corticosteroids are reported to b~ more effective in inducing oocyte maturation in Japanese medaka~ Oryzias latipes (Hirose 1972), Indian catfish, Heteropneustes fossilis (Goswami and Sundararaj 1974) and zebra fish," Brachydanio rerio (Van Ree et al. 1977). However, Masui and Clarke (1979) were of the opinion that the action o f corticosteroids may be non-specific in oocyte maturation and they suggested that ovarian follicular layer produces progesterone like steroid which is responsible for final maturation in teleosts. Thus, the precise nature of MIS in fishes remain uncertain. In the present study we compare the effectiveness of 15 different steroid hormones on in vitro oocyte maturation induction in three species of economically important major carps of India (Labeo rohita, Cirrhinus mrigala and Catla catla). The objective of this study was to determine which of these is most,potent for induction of oocyte maturation.

Material

and methods

Adult female L. rohita, C. mrigala and C. carla were obtained from Vikrampur fish farm, Department of Fisheries, Varanasi in the month of July before their spawning started. Before commencement of experiments, the oocytes of these fishes were fully grown and the GV was centrally located when examined under a dissecting microscope. Diameter of the oocytes of L. rohita, C. mrigala and C. catla were0.71 + 0.01,0.74 _+ 0.02 and 0.69 _+ 0.01 mm (E + SEM), respectively. All 15 steroids used in this study were purchased from Sigma Chemical Company, USA. They were dissolved in filtered ethanol and added to the incubation medium to produce concentrations of 0.001,

0.01,0.1 and 1 #g/ml and a final ethanol concentration in the incubating medium during culture of 1070. Two different experiments were conducted. In the first, estradiol-17/3, androgens and corticosteroids, and in the second experiment, progesterone and other pregnene derivatives were used as the inducers. The fish were killed by decapitation and their ovaries were transferred to a petridish containing sterile incubating medium (Upadhyaya and Haider 1986). The oocytes were separated from each other. Full-grown, but immature folliculated oocytes (70-80) were incubated in 3 ml of medium with or without steroids (t = 23 + I~ Three replicates were kept for each concentration. All the incubates were maintained for 24h, after which the oocytes were fixed in 70~ alcohol, dehydrated in absolute alcohol, cleared in xylene and examined under a microscope for the incidence of GVBD. The rate of GVBD was expressed as the mean value of log-transformed percentage of GVBD. The level of significance was analysed by two way analysis of variance (ANOVA) followed by Students NewmanKeuls' multiple range test.

Results

The relative effect of various steroids on GVBD in L. rohita, C. mrigala and C. carla at all the four concentrations tested are summarized in Tables 1 - 3. Estradiol-173 and androgens were ineffective in inducing GVBD at their lowest concentration in L. rohita and C. mrigala. However, in C. catla androsterone and dehydroepiandrosterone were effective in inducing GVBD at their lowest concentration. All three corticosteroids used in the study induced GVBD in C. carla even at their lowest concentration (p < 0.01). However, in L. rohitaand C. mrigala only cortisone was effective. All three progestogens induced GVBD at all concentrations in each of the three carp species, with 17u,203-diOHprog being the most potent. Among 53-reduced pregnene derivatives, all were effective in inducing GVBD in L. rohita; while in C. catla 53-pregnane-17o~-ol-3,20-dione and 53pregnane-3u, 17u,203-triol were effective, and in

291 Table I. In vitro i n d u c t i o n of g e r m i n a l vesicle b r e a k d o w n o f the oocytes o f Labeo rohita by v a r i o u s steroids. Steroid c o n c e n t r a t i o n s Steroids 0

1

0.1

0.01

0.001

0 . 7 5 6 8 + 0 . 1 3 8 5 '~

0.9109+_0.1064 a.b,A 0.7879+_0.1737 a,A

0.8698_+0.0219 a.A 0.8344_+0.0702 a.A

0 . 6 7 6 3 + 0 . 1 2 4 8 a.A 0.7616_+0.1134 a.b.A

0.6894 _+0.0522 a,A

0.9932 + 0.0934 a.b.A

0.9020_+ 0.0610 a,A

0.7762 _+0.0660 a.b.A

0.6990 -+ 0.0545 a,A

androsterone

1.0124 + 0.0625 a,b,A

0.9128 +--0.0558 a'A

1.0847 _+0.1189 a'b'A

0.9178 -+ 0.0513 a'A

0.9108 _+0.0688 a'b'c'A 0.8530-+ 0.0571 a.b.C. A

0.8562 -+ 0.0371 a,b.A

Epiandrosterone

1.2335 +__0.1049 b'c 1.2336 -+ 0.0401 b.a.C 1.2917_+ 0.0514b. a

1.2051 -+ 0.0997 a'a'c 1.1603 -+ 0.0616 a'a'C

I. 1424 -+ 0.0206 b'c'a'c 1.0603 -+ 0.0134 a'b'c'A'c

0.8688 + 0.0791 a.b.A.B 1.0284 + 0.1383 a'b'A'C

1.2458 _+0.0843 a'a

1.2188+_0.1274 c,a

1.1210--+0.1179 b.a

1.6538 _+0.0232 a'b'~

1.4185 +_0.0358 a'B'c

.3744 -+ 0.0298 a.8.c

1.2615 + 0.0339 a.B

1.6518_+0.0125 b.c.a

1.5966 + 0.0987 a'b'B

.4658 +_ 0.0400 a'B

1.3785 __.0.0094 a.b.a

1.8607 _+0.0340 b'a

1.7996 +_0.0041 b,~

.7280 _+0.0280 b'a

1.6080 -+ 0.0800 b.a

20-One 5/J-Pregnene- 17~-

1.3896 _+0.0903 a'c'a

1.3434 -+ 0.0521 a,a

.3194 _+0.0760 a'a

1.2772 + 0.0837 a.l~

ol-3,20-dione 5r P regnene-3~, 17c~-

1.3754 +_0.0689 a'c'l~

1.3453 -+ 0.1314 a'8

.2151 _+0.0658 a'a

1.1317 +_0.0396 a,a

diol-20-One 5bJ-Pregnene-3c~, 17~, 20/3-triol

1.4027 _+0.0406 a'a

1.3439 _+0,0554 a'8

.1716 +_0.0856 a'a

1.1831 _+_0.0701 a.a

1.3079 _+0.0121 a,c,a

1.2891 _+0.0937 a'8

1.2522 -+ 0.1137 a'8

1.1168 + 0.0201 a.B

Control Estradiol-17/3 Testosterone Androsterone Dehydroepi-

0.6744 -+ 0.0678 a,A

0.7583 -+ 0.0549 a.b.A

Deoxycorticosterone Hydrocortisone Cortisone Control Progesterone 17c~-Hydroxy-

0.7305_+0.1315 A

Progesterone 17~,20B-dihydroxy4-Pregnene-3-One 5/3-Pregnene-3c~-ol-

D a t a are s h o w n as the m e a n l o g - t r a n s f o r m e d ~ G V B D _+ SEM of three replicate i n c u b a t i o n s ; steroid c o n c e n t r a t i o n s are s h o w n as tag/ml; a ' b " v a l u e s bearing d i f f e r e n t superscript in the vertical line are s i g n i f i c a n t l y d i f f e r e n t (p < 0.05) f r o m each other; A,a.Cvalues b e a r i n g d i f f e r e n t superscript in the dose level ( h o r i z o n t a l line and c o n t r o l ) are s i g n i f i c a n t l y different (p < 0.05) from each other.

C. mrigala only 5/3-pregnane-3c~-ol-20-one was effective. Discussion

As was found in the study reported here, several other investigation on fish oocyte maturation indicate that estrogens are generally not effective in inducing final oocyte maturation (Goetz 1983). However, estradiol-17~ in O. latipes (Hirose 1972, 1976) and estrone in B. rerio (Van Ree et al. 1977) were effective in inducing GVBD. Among androgens, testosterone was found to be ineffective in inducing oocyte maturation in H. fossilis (Goswami and Sundararaj 1974), Anguilla anguilla (Epler and Bieniarz 1978), Salmo gairdneri

(Nagahama et al. 19.80) and Mystus vittatus (Upadhyaya and Haider 1986), whereas its moderate effectiveness has been reported in a number of fishes (Goetz 1983). In our investigation testosterone did not show maturation-inducing activity. Dehydroepiandrosterone induced oocyte maturation in H. fossilis (Goswami and Sundararaj 1971, 1974) and Salvelinusfontinalis (Goetz and Bergman 1978) but in Cyprinus carpio (Epler et al. 1980) it had no inducing activity. Dehydroepiandrosterone and epiandrosterone were slightly effective in inducing GVBD at their higher concentrations in C. mrigala and C. catla oocytes but were not effective in L. rohita. Androsterone was also ineffective in induction of oocyte maturation in L. rohita and C. mrigala even at higher concentrations. However, it was ef-

292 Table 2. In vitro i n d u c t i o n o f g e r m i n a l vesicle b r e a k d o w n o f the o o c y t e s o f Cirrhinus mrigala by v a r i o u s steroids. Steroid c o n c e n t r a t i o n s -Steroids

o 0

1

0.1

0.01

E s t r a d i o l - 17~ Testosterone

1.2856 ::!:0.0537 a'c 1.1832 _+0.0422 a'A

1.0597 :l: 0.0802 a'B

0.8259 _+ 0.1272 a,A

0.8199 • 0.1303 a'A'a

I. 1544_+ 0.1096a,0. A

1.1234_+ 0.0614b, n

Androsterone Dehydroepi-

1.2779_+0.0143 a.a

1.2524 _+0.0396 a'b'A'B I. 1764 _+0.0581 b,A.a

0.9835 +- 0.0651 a'A 1.0545 +- 0.0665 a'b'A'B

androsterone Epiandrosterone

1.2770 + 0.1289 a,a 1.4114 + 0.0509 a.c

1.3148 + 0.0896 a.b.a

1.2982_+0.0311 b.a

1.1771 + 0.0540 b,A,B

1.3922 +- 0.0569b.a.c

1.2038 +- 0.0400b.A,a, C 1.1588 +- O.0317b,A, c

Deoxycorticosterone Hydrocortisone

1.2571 _.+0.0362 a ' a ' c 1 .2446 • 0.0209 a.b,A-C 1.2151 +- 0.0399 b.A.C I. 1869 _+0.0304 a,b,A.B 1.2200 _+0.1328 ~ 1.2853 +_0.0390 a'a

Cortisone

1 . 4 1 0 9 + 0 . 0 4 6 8 a.a 9 I .3741 +- 0.0595 b,a

Control

Control Progesterone 17u-Hydroxy-

0.001

1.0038 _ 0.0703

1.3761 + 0.0153 b,a

1.2035 _+0.0811 b.B.c 1.0075 +- 0.0280 a.b.A.a 1.3175 +- 0.0540 b.B

1.0241 _+0.0519 A 1.6084 +- 0.031 I a.b.C

.4275 _+0.0489 a.b,a.c

.3833 +- 0.0982 a,b.B,C 1.2919 +- 0.0854 a.a

1.6600 _+0.0767 a'b'c

.6099 + 0.0360 T M

.4587 _+0.1245 b.a.C

1.3787 • 0.0457 a,a

1.8418 +_0.0300 b'a

.8311 -+0.0378 c.a

.7193 +_0.0742 c.a

1.6600+._+ 0.0717 b.B

20-One 5B-Pregnene-I 7ct-

1.3862 +- 0.0985 a'B

.3505 + 0.0820 a.b.a

.3401 _ 0.0868 a.b,a

1.2654 +..+0.1081 a.B

01-3,20-dione 5 ~ - P r e g n e n e - 3 u , 17ct-

1.4688 __ 0.0823 a'8

.2678 +- 0.0574 a,A,a

.3157 +- 0.0415 a,b.a

1.2205 +- 0.0287 a.A.a

diol-20-One 5 B - P r e g n e n e - 3 a , 17u,

1.4254 __ 0.0807 a'B

.1515 +- 0.0801 a.A

.1521 + 0 . 0 9 0 7 a.A

1.0909 +- 0.0339 a.A

1.3665 __ 0.0851 a'B

.3841 _+0.1077 a,b.B

.3540 + 0.0570 a.b,a

1.2188 _+0. 1107 a.A.a

Progesterone 17ot,20B-dihydroxy4-Pregnen-3-One 5/~-Pregnene-3u-ol-

20B-triol

D a t a are s h o w n as the m e a n l o g - t r a n s f o r m e d % G V B D +- SEM o f t h r e e replicate incubations; steroid c o n c e n t r a t i o n s are s h o w n as # g / r o l ; a.b,cValues bearing d i f f e r e n t s u p e r s c r i p t in the vertical line are s i g n i f i c a n t l y d i f f e r e n t (p < 0.05) f r o m each o t h e r ; A'B'CValues b e a r i n g d i f f e r e n t superscript in the dose level ( h o r i z o n t a l line a n d c o n t r o l ) are s i g n i f i c a n t l y d i f f e r e n t (p < 0.05) f r o m each other.

fective, even at lowest concentration, in C. catla. Upadhyaya and Haider (1986) reported that androsterone was effective in inducing oocyte maturation in M . vittatus. In fact, there is no specificity in the action of androgens on oocyte maturation. Sundararaj and Goswami (1977) suggest that androgenicity and oocyte maturation activity are two independent phenomena. However, I wamatsu (1978) hypothesized that the androgenicity of androgens also account for their maturation inducing property. The result reported here also show that there is probably no relation between androgenicity and maturation inducing capability of androgens in general. Maturation-inducing activity of corticosteroids and progestogens among C21 steroids is more con-

troversial and confusing. Progesterone and its 17c~ and 20B-hydroxy derivatives were effective in a number of species, but 17a,20B-diOHprog was the most active steroid (Goetz 1983). However, in some species, certain ll-oxygenated corticosteroids are also effective (Hirose 1972; Goswami and Sundararaj 1974; Van Ree et al. 1977). In the present study also 17ee,20B-diOHprog was found to be the most effective inducer of GVBD in all the three species; this steroid has been identified as the major metabolite when 14C-labelled progesterone or 17o~OHprog is incubated with cell free ovarian homogenates of P. altivelis (Suzuki et al. 1981a) or O. r h o d u r u s (Suzuki et al. 1981b) treated with salmon gonadotropin. This steroid has also been identified in the plasma of several species (Idler et al. 1978;

293 Table 3. In vitro i n d u c t i o n of g e r m i n a l vesicle b r e a k d o w n o f the oocytes o f Catla catla by various steroids. Steroid c o n c e n t r a t i o n s Steroids 0 Control

I

0.1

0.01

0,001

0.8835 +_0+0755 ^ 0.9767 + 0.0338 a'A 1.0212_+0.0219 a.'~ 0.9993_+ 0.0456 a.~' 1.0879 + 0.0516 a,b.A 0.9826 +- 0.0259 a'A 0.9685 _+0.0058 a'^ 1.3091 _+0.0156 h.c.r t.1549+- 0.0586 a,t~,B.c 1.1099 + 0.0073 a'b'13'c

0.9775 _+0.0351 a.b.A

1.3018 + 0.0278 b.c.(" 1.2544+_ 0.1301t'.B.r 1.2101+_0.1051 ~.c,8 1.1391_+ 0.0262 a'b'B

1.2358 +_0.0280h.r 1.0868 +_0.0448 a'b'B

1.0634 +_0.0553 a.b,B 0.8622 _+0.0329 a.a

1.3705 _+0.0457 '.l~ 1.2833 _+0.0247 t'-r~ 1.2316_+0.0200 ~-r 1.1533 + 0,1315a.h- I~ 1.2934 _+0.0291 h.~.H 1.2764 _+0.0499 h'B

1.1973 __ 0.0255 a,b,B

1,1541 + 0.0218 b,B

1.1408_+0.0729 a , ~ - B 1,2048 _+0.0994 a'h'B

1.0754_+0.0182 a.h,B I. 1467 + 0.0535 b'B

1.5762 _+0.0170 t'.r

1.3868 _+0.0346 a.t'.B

1.2848 +_0.0343 a.h.n

1.2609 + 0.0117 b.B

Progesterone 17~,20~3-dihyd roxy-

1.7458 + 0.0219 c.D

1.5377 _+0.0116 r'.r

1.4275 _+0.0197 T M

1.3374 + 0.0295 h.B

4-Pregnen-3-One 5~-Pregnene-3a-ol-

1.8789 _+0.0239 ~.C

1,8296 _+0.0142 '.r

1.7014 _+ 0.0617 t+a.c

1.5402 _+0.0363 c.B

20-One 5B-Pregnene- 17c~-

1.3556 + 0.1082 a,13

1.3245 +_0.0368 a.n

1.2613 + 0.0052 a'b'l~

1.0060 + 0.0420 a.A

1.4198 _ 0.0540 a.h.D 1.2792 + 0.0166 a.t'.D

1.1916_+0.0344 a,c

1.0195 + 0.0105 a.B

1.2593 + 0.0595 a.r

1.0863 _+0.0595 T M

0.9665 + 0.0880 a.A.a

1.2399 + 0.0831 a,b.C

1.0421 _ 0.0515 a.B

Estradiol-17d Testosterone Androsterone Dehydroepiandrosterone Epiandrosterone

0.9518 + 0 . 0 4 1 0 a.b.A 1.0515 + 0.0655 a.b.a

Deoxycorticosterone Hydrocortisone Cortisone Control Progesterone 17c~-Hydroxy-

ol-3,20-dione

0.8508 _+0.0895 ~

5 B - P r e g n e n e - 3 a , 17c~diol-20-One 5~- P regnene-3c~, 17c~, 20B-triol

1.2234_+ 0.0359 a+t

1.3793 _*0.0285 a.h.r 1.3067 + 0.0874 a-C

D a t a are s h o w n as the m e a n l o g - t r a n s f o r m e d ~ G V B D + SEM o f three replicate i n c u b a t i o n s ; steroid c o n c e n t r a t i o n s are s h o w n as t~g/ml; a.hxValues bearing different superscript in the vertical line are s i g n i f i c a n t l y d i f f e r e n t (p < 0.05) f r o m each other; A'B'C'DValues b e a r i n g d i f f e r e n t superscript in the dose level ( h o r i z o n t a l line and c o n t r o l ) are s i g n i f i c a n t l y different (p < 0.05) from each other.

Schmidst and Idler 1962; Campbell et al. 1976; Truscott et al. 1978; Yamauchi et al. 1984; Hirose et aL 1985; Pankhurst et al. 1986; Suzuki et al. 1987). Nagahama and his coworkers have identified this steroid as natural MIS in amago salmon by several direct and indirect studies. All the above studies suggest that 17c~,20/3-diOHprog is the natural MIS. From the present study also it appears that most probably 17c~,20~-diOHprog is the most effective MIS. Among 5/3-reduced pregnene derivatives, 513pregnane-17a-ol-3,20-dione and 5/3-pregnane-3a, 17c~,20/3-triol were effective in C. catla and in C. mrigala 513-pregnane-3c~,ol-20-one was effective in inducing oocyte maturation at all the concentrations, while in L. rohita all were effective GVBD-

inducers. Upadhyaya and Haider (1986) also reported the effectiveness of 5/3-pregnane-17a-ol-3, 20-dione and 5~3-pregnane-3a,17c~-diol-20-one on M. vittatus oocyte maturation. Hov~ever, in amago salmon and rainbow trout (Nagahama et al. 1983), 5/3-pregnane-17c~-ol-3,20-dione and 513-pregnane3a, 17a,2013-triol had an effect at higher concentrations only. In M . vittatus also, 5/3-pregnane-3a, 17a,2Oj3-triol induced oocyte maturation at higher concentration (Upadhyaya and Haider 1986).

Acknowledgemenls This research was supported by grants from Department of Environment, Government of India.

294 W e a r e g r a t e f u l t o D r . U . Rai f o r his h e l p in s t a t i s t i cal a n a l y s i s .

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