103
Sex steroid hormones in the pathogenesis of chronic subdural haematoma R. I , Giuffre, E. Polm ai . G. Liccardo' , R Sciarrai . R S. Pastore' , G. Concolino' Institute ofNeuros urgery, 2nd State University afRome "Clinica Medica V~ , LaSapienza University ofRome
Summary
In or der 10 verify whet he r horm onal factors could be involved in the path ogenesis of Chronic Subdural Haem atoma (CSDH), bas ed on clinical and epidemiological demonstration of high er ineiden ce of this disease in male patients and particularly in those with high urinary estrogen values , Estradiol (ER) and Progest erone (PR) Receptors were studied in th e Haematoma Exte rn al Membrane (HEM)in 18 mal e and 7 female CSDH patients. Th e observed higher ineidence of ER and PRin male rather th an in female pati ent s (73 % vs 27 % and 72% vs 28% for male a nd female pati ent s resp ectively), and the high er conce ntra tion of ER in Ihe HEM ofmale rather then female pati ent s (55 ± 15 S. E. vs 13 ± 7 S.E. fmol/m g pr otein) suggest that this pathological pro cess, which affects ind ividu als wh ose gonadal activity is quiescent , is mainl y dependent up on hormonallocal effect played hy estrogen compounds on the HEM of the male pati ents. In this sex, in fact, whose tissue s are not usually ada pte d to an estro gen action, th e efTect of estrogens on a responsive tissu e such as the newly-vascularized HEM could lead to an incr eased formation of tissue Plasminogen Activa tor (t-PA), a com pound that , escaping into the subdural collection, could maintain a local hyperfibrinolysis with form ation of Fibrino gen Degrad ation Products (FDP). Ther efor e local hyperfibrinolysis enha nced by ste roid horm ones a nd the subse quent CSDH may perhap s be influenced by the pr ophyl actic or adjuvant treatm ent with inhibitors either of the aromatase activity or of the estrogen action at receptor level.
Sexualhormone in der Pathogenese des ch ronisch en subduralen Hämatoms Um nachzuweisen , daß hormon ale Faktoren bei der Pathogenese des chronische n subduralen Häm atoms [CSDH) eine Rolle spielen - zu vermuten durch den klinischen un d epidemiologischen Hinweis der höh eren lnzidenz bei Männern, inshesonder e be i denen mit höher en Östrogen -Werten im Urin - wu rde n bei 18 männlichen und 7 weiblichen Patient en mit CSDH die Östrogen (ER)- und die Proges teron (PRl-Rezept oren in der äu ßere n Häm atom- Kapsel (HEM) bes tim mt. Die gefundene höher e Rate von ER un d PR hei männlichen gegenüber den weiblichen Patienten (73% vs 27% und 72 % vs 28 %) und die höhe re Konzen tra tion von ER in der HEM (55 ± 15 vs 13 ± 7 fmol/m g Protein) lassen vermuten, daß dieser pathologische Prozeß, der Individu en mit ruhender Gona denfunktion befallt, hauptsäch lich von einem lokalen horm onalen Effekt östrogene r Verbindungen in der HEM der männlichen Pat ienten abhä ngig ist. Bei Mannern ist das Gewebe gewö hnlich nicht an die Östroge n-Effekte adap tiert und bei der Reaktion von Gewebewie der neuvaskularisierten HEMkann es zur erhöhten Bildung von Plasminogen -Faktor (t-PA) komm en. Diese Substanz kann beim Übert ritt in da s Häm atom zu einer lokalen Hyperfibrinolyse mit gleichzeitiger Ernie drigung von Fibrinogene n (FDP) führen. Dahe r kann die lokale Hyper fibrinol yse - verstärkt durch Steroid -Hormo ne und n achfolgend es CSDH - vielleicht durch die prophylaktische oder zusätzliche Beha ndlung mit Antiöstroge nen auf dem Rezeptorenni veau oder mit Antiaromatases ubstanzen .
Key-Words Sub dural haematoma - Steroids - Estradiol - Progest eron e - t-PA- Hyperfibrinolysis
Chro nic sub dura l haematoma (CSDH) has a higher ineidence in male tha n in fema le patients (18), affects male patients with urinary estrogens higher than those found in norm al subjec ts (28); it is more common duringthe 7th decade of life (6, 18, 19 ) i.e. durin g a period of quiescent gonadal activity.
Neurochirurgia 35 (1992) 10 3-1 0 7 © Georg Thieme Verlag Stuttgart · New York
Inside the newly-forrned haematoma exter nal memb ran e (HEM) the ecta tic ca pillaries (10,15,26,32) are believed to be similar to the vascular network of skin in alcoholic cirrhotic patients with elevated estrogen levels (28). Furthermore the fibrinolytic activity a nd tissu e plasmin ogen activator (t-PA) of the haemato ma fluid and the HEM respectively can be compa red to th ose of menstrual bleedin g and ute rine mucosa (13).
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Neurochirurgia 35 (1992)
R.. Giuffre, E. Palme. G. Liccardo. F. S ciarra. F. S. Pas tore. G. Concoltno
Table I Concentration 01 Estrogenreceptors (ER) and Progesterene receptors (PR) inNormal DuraMater Patient
Ag. (y,)
Sex
I
65 32 41 54
2 m
3 4
m
ERe
ERn
PRe
(fmol /mg protein)
(fmol/mg DNA)
(fmol/ mg protein)
33 n.d. 12 50
neg. 56 76 150
43 75 neg.
9
C = cytosol; N = nuclear; N.D. = not determined;neg. = negative
Table 2 Presence ot Estrogen receotcrs (ER) and Progesterene Receptors (PR) in the cytosol and nucleiof HEMofCSDH patients.
ERe PRo ER, PR,
total
male
15/20 (75%) 18/23 (78%) 15/ 22 (68%) 5/8 (63%1
11115 (73%) 13/18 (72%) 10/15 (67%) 3/5 (60%)
female
:..-:..-_ 4/15 (27%) 5118 (28%) 5/15 (33%) 2/5 (40%1
Tabl.3 Concentration of cvtcso! ERand PRinthe HEM ofCSDH patients. male ____
ERe PRe
I
female (fmol/mg of protein ± S. E.)
55± 15 37 + 7
13 ± 7 35 ± 21
S.E. = standard error
In attempt to advanci ng our knowledge in the path ogenesis of CSDH, estrogen receptor (ER)and progesterone receptor (PR) were measured in the HEMofCSDH. Material s and Methods The HEM wa s removed at surgery under local anes thesi a from twen tyfive CSDH patients , eightee n male and seven female {mea nages 69 ± 7 yea rsold and 71 ± 13 yea rs old for male and female r especti velyl. Specimens of dura ma ter Iying a bove the CSDH were sim ultaneously removed from four patients (3 male and 1 female patient ). Four dura mater speci me ns from glioma patients (2 male a nd 2 female) were also studied for comparison. Specime ns of HEM and dura mater were store d at - 70 °C until processed. Cytosol fractions and nuclear extracts we re then obtained with differen tial centrifugation. Methodologica l deta ils ha ve been published elsewhe re (8, 9). Total cytos ol ER (EHe) was measured in 20 specimens an d total nuclear ER (ERn) in 22 specimens of HEM using the method of Sica et al. (27 ). Total cytos ol PR(PRJ was measured in 23 speci mens and total nuclear PR (PRn) in 8 speci mens of HEMusi ng low and high sa lt conce ntration of sodium molybdate respec tively (23) . Only single saturation dose analysis could be performed on acc ount of the small size (80-1 00 mg) of available HEMfragments. After separat ion of free and bound ligands , radioactivitywas meas ured on a Packard 460 CD scintillation spectrometer, protein conce ntration by the Bradford method (5) and DNA conte nt by Burton procedure (7).
The thres hold values were fixed at 3 fentomoles Ifm oll per milligram (mg) of prc te in for cytos ol receptors and at 50 fmoVmg DNA for nuclear receptors .
Results St eroid receptors in normal dura m ater The concentration of'Ell, and ERnwe re similar in the normal dura mater taken from male and fem ale patients . The PRc content , on the contrary, was higher in normal dura mater of the women than in that of the men (Table 1).
Steroid recep tors in HEM Incidence of cytoso l and nuclear ste roid receptors
The inciden ce of ER, was 75% (15/20) an d that of PR, 78 % (18/ 23). Both ER, an d PR, in HEM were more frequent in male rather than in female patients (73 % vs 27%; 72 % vs 28 % for ER, and PR, respectively). Th e incidence ofE R, was 68% (15/ 22) and that orrn, 63 % (5/ 8). ERn was more frequent in the specime ns taken from male ra ther than from fema le patients (67 % vs 33 %) (Table 2). The five PRn we re found in three male and two female patients. Concentration of cytoso l steroid receptors
The concentration of ER, in th e HEM of the male patient s showed mean value of 55 ± 15 S. E. fmoVmg protein with a ra nge from 3 to 104 fmoVmg pr otein. Ther efore the ER, content was slightly higher than that found in the normal dur a mater taken from male patient s (Table 3). Furthermore the ERc values in two specimens of dura mater taken from CSDH patients we re different from those found in the HEM of th e corresponding patients .
The ER, content in the HEM of the four female patients (13 ± 7 S. E. fmoVmg prot ein) was slightly lower than that found in the normal dura mater taken from a femal e patient (33 fmoVmg pr otein), Further more in one female pati ent th e amount of ER, in th e HEM was found compa ra ble to th at measured in the dura mater laying above th e CSDH. The concen tration of PR, in th e HEM of the male patients showed a mean value of 37 ± 7 S. E. frnol/mg protein with range from 5 to 85 fmoVmg protein. The refore , as for ER" also the mean value of PR, in HEM was higher tban that found in norma l dur a mater taken from male patients (Table 3). Two out of the three dura mater sp ecimens lying above the CSDH had PR, values different from those found in HEM of the corre sp onding patients. The concentration of PR, in th e HEM of the fem ale pati ent s sho wed a mean value of 35 ± 21 S. E. frnol/ mg protein with a ra nge from 9 to 91 frnol/mg protein . Therefore the ER, value in HEM was lower than that found in normal dura mater taken from fem ale patients.
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Neurochirurgia 35 (992)
Sex steroid hormones in the palhogenes is oJ ehrenie subdura l haematoma
The mean value of ERn content measured in
the HEM of 10 male patient s was 77 fmoVmg ONA, a value comparable with that obtained in 2 norm al du ra mater, whilst ER, was found only in 1 out of the 3 sa mpies of dura mater laying above CSOH. However the data obtained in these 3 dura mater sampIes were concordant with those measured in the 3 HEM specimens of the corresponding
SUBDUAAL BLEEDING
••
reebscrptjon
il'ljury coagulopathy arrtlcoagulanl lhelapy
QTHERCAUSES
lr nectous osease
/
meningeal eareinomatosis
fibfoblaslic 1 reecnon
NEOMEMBRANE.
NO EVOLUTION jbyct1angep,m,linding)
3
2 inc reased t - PA
NEOPLASTIC EVOLUTION? meningioma
sarcoma
I
c:~) m;"or
patients . Furthermore it is important to underline that negative results we re obtained in 7 out ofth e 22 specimens
examined: 86% (6/7) oft his ER, negati ve HEM specimens were remov ed from male patients.
d
The mean value of'Eli, content measured in the HEM of 5 fema le patients was 99 frnol/mg ONA, higher than that found in one normal dura mater specimen. The dura mater removed from one femal e CSDHpatient was ERn
;"
CSDH
negative as th e corres ponding HEM taken from the same patient.
Fig. l
The measurement of PR n was performed only in 8 HEM specimens, five ofw hich were provided with
Studies perform ed since 1970 demonstrated that the pathog enetic mechanism of a CSOH is represented by the high content of tissue plasmin ogen activator (t-PA) in the ectatic capillaries of HEM, which exudes into the fluid collection, transforming plasminog en into plasmin. This active compound breaks down fibrin with formati on of fibrinogen degradation pro ducts (FOP) and indu ces continuous microbleeding (13, 30).
nuclea r PR.The PR nmeas ured in the dura mater specimens
taken from two CSOH patients was found negative as the PR, in th e HEMof the corres ponding patients . The comparison of the receptor content in
the sampie of HEM of male and fernale CSOIl patients showed that the values of cytosol EHwer e higher in HEM of male than female patients (Table 3); on the contrary, those of nuclear EH were higher in HEM of female than male patients. The values of cytosol PR in the HEM of both sexes were similar.
Sites ofpossible steroid hormones action inthe pathogenesis of CSDH.
The t-PA has the highest value in the HEM (followed by the dur a mater and arachnoidl. whilst th e haematoma content lacks fibrinogen and plasminogen in spite of an extrao rdinary lar ge amount of FOP. This situation is similar to that found in the menstrual blood and
Discussion
It is weil accepted that the primary etiological factor resp onsible for CSOH is the tearin g of corticodura l brid ging veins (31). The bleedin g usually occurs in either a virtual space (25) or a cellular compartment between the dura and the arac hnoid membranes (10), mostly in elderly people becaus e of concomitant cortical atrophy (6). This extravascular blood in some cases can be easily reabsorb ed. whilst in other cases is respon sible for
a fibroblastic reaction leading to the formation of a highly vascularized subdural membrane . Experimental evidence is in favour of a stimulating action on the inner surface of the
dura mater by th e blood fibrin (1). This neomembrane may be found unchanged at aut opsy, whilst in some patient s a local hyperfibrinolysis that interfer es with haemostatic mechanlsms, is respon sible for the formation of a bloody collection betw een the dura and the arachnoid membran es:
the CSOH (14,17). It is interesting to remin d also the reported
formation of a meningioma (2) or of a sarcoma (16) inside the HEM of CSOH patient s, as weil as the ass ociation of a
uterin e mucosa (the former being rich in FOPand the latter rich in t-PA) which ar e affected by horm onal modifications du ring the menstru al cycle. In this respect it has been demonstrated th at the produ ction oft-PAin vitro is stimu lated hy physiological levels of estrogens and further potenti ated by progesteron e (21). It is known that th ese steroids act through their own receptors . For this reason, based on the above men -
tioned epidemiological and clinical data, we decided to see k for the presence of ER and PR in the HEM of CSOH. The results
of
the
present
investigation
support
the
hypothesized pathogenetic role played by the steroid hormones in the formation ofCSOH. The presence of both ER and PR in th e cytosol and nuclea r fractions of th e HEM studied is accompained by a preferential distribution of steroid receptors in
the IlEM of male rath er than female CSOH patients (ER, 73 % vs 27 %; PRc 72 % vs 28 % for male and fema le respec-
tivelyl, Furthe rmore th e higher content of cytosol ER in the HEM of male rather than fema le CSOH patients (55 vs 13 fmol/rng protein) could perhaps account for the sex related higher incidence of CSOH in male rath er than female patients .
meningioma with a newly-formed subdural membrane
without a collection ofblood (22).
The prevalence of ster oid receptors and the higher content of ERin the male rather than female patient s cannot be explained on the basis of the stimulation ofrecep-
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Concentration of nuclea r steroid receptor
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Neurochirurgia 35 (1992)
R.. Giuffre. E. Palma. G. Llccardo. F. Se iarm . F. S. Pastare, G. Conco/ino
tors by eircu lating hormones. CSDH. in fact, is a disease of elderly pat ients, whose gonadal activity is usually quiescent. However it must be taken into eonsideration that some enzyme activities could be responsible for the formation of active metabolites from adrenal and gonadaJpreeursors. This concept is su pported by the increased aromatase aetivity reported in elderly men, whieh can be respons ible for the formation of estrogens from testosterone and androstenedione . It is known that this enzyme aetivity plays an important role in the pathogenesis of hum an ben ign prostatie hyperplasia, which affects elderly men. The refore the reported higher incidence and coneentration of ER in the HEM of male CSDH patients could perh aps be dependent upon the conversion of circulating androgens into est rogen s by the high aromatase activity in the male patients. Furthermo re the tissue response to hormonal stimulation and mai nly to estrogens is more pronounced in male than in fema le vascular network , not because of a lack of progesterone and PR. whieh appear to be uniformly distributed in the two sexes , but because of the different thresholds of response. In women, in fact, vesse ls are usually adapted to high estrogen values . This abnorma l tissue response to estrogens in male patients may aceount for the values of both ER, and PR, of male CSDH pat ients high er than those measured in the norm al dura mat er tak en from male glioma patients usually ofyo unger age than the CSDH pat ients. On the contrary, in the female patients whose tissue are usuall y ada pted to estrogen stimulation. the values of both ER, and PR, in the HEM are lower than those measured in th e normal dur a mater tak en from femal e younger glioma pati ents. As far as the role played by steroid hormones on the pathogenetic mecha nism of CSDH (Fig. j ), estrogens could be involved in the formation of the newlyvaseularized externat membrane, for their action on the neoangiogen ic process (12) and on the mesenchymal cells (24). In this resp ect it is important to note that other ste roid horm ones such as glucocorticoids are known to be related to fibroblasti c rea ctions (29). In addi tion to this dire ct effect, stero id action could also be dependent upon a receptor mediated meehanism based on genomie expression of hormonal stimulatio n. This actio n could lead to the proliferation of the innermos t layer of th e dura mat er and parti cularly to the mesen chymal proliferation ofthe HEM. Moreover ER and PR ha ve been report ed in cra nial an d spinal meningiomas (4. 9, 20). The assoeiation of a men ingeal tumor with a subdural ha emat oma (2. 16) and that of a meningioma with a subdural neomembrane without bloody collection (22) have been report ed too. It is tempting to speculate a possible influe nce of ste roid hormones on both th e lesions . Furthermore the effects of estrogens an d progesterone are more likely to be predominant in mainta ining local hyperfib rinolysis through thei r action on the levels of t-PA. In this respect the presence of ER and PR in the HEM can be consi dered in favour of an horm onal action on this tissue: th e steroid horm ones could play at level ofthe HEM the sa me act ion on t-PA they play at endometrial mueosa level.
The receptor mediated effects of steroids could also explain the higher values of t-PA found in th e HEM than in the dura mater on account ofthe higher content of steroid receptors in the former rather than in the latter. The hormonal effect on t-PA. although not th e primary event leading to the CSDH, can be consi dered as one of the main factors responsible for the fluid collection .
The proposed hormonal pat hogenetic mechanism of CSDH could lead to a medical approac h to CSDH patients, different from those already proposed (3. 11). In fact, the availability of some dru gs with antiaro rnatase activity or with anti estrogen action (able to block the intereonversion of androgens into estrogens or to interfere with estrogens at receptor level] allows to atte mpt a prophylactie therapeutie regimen of patients who experienced a skull injury. in orde r to inhibi t the local hyperfibrinolysis induced by the hor mones, an d eventually to reduce the ineidence of formatio n of CSDH. This medical treatme nt. however, can also be taken into conside ration as adjuvant of CSDH pati ents who underwent surgery. In conclusion, the results of the prese nt study see m to support the hypothesized hormonal effects in th e path ogenesis of a CSDH. The biochemieal data sustai n th e clinical and epidemiologieal investigations quoted in the literature. The action of estrogens and progesterone, through their own receptors, see ms to be particularly relevant at the level ofthe HEM. where they can increa se th e tPAlevels and therefore maintain th e local hyperfibrinolysis . Adjuvant and prophyl actic antihormal treatment may be suggested. References I 2
3 4
5
6 1
I
9
10
11 12
Apfelbaum. R. J. . A. N. Guthkelch. K. Shulman: Experimental production ofsubdural hematomas . J. Neurosurg. 40 (1974) 336- 346 Baskinis. N.. A. Grotennuis. H. Wandt: Chronic subdural hematoma associate d with an intracapsular meningioma . Case report and short review of the literature. J. Neurosurg. Sei. 28 (1984) 17-23 Ben der. M. B.. N. ChristoJl: Nonsurgical treatment of subdural hematomas . Azch. Neurol. (Chi c.] 31 (1974) 73-79 Blankenstein. M. A.. P. M. 1. 1. Bems. G. Blaanw. J. H. H. Thijssen: Search for estrogen receptcrs in human meningioma tissu e section with a monoclona l antibody against the human estrogen receptor. Cancer. Res . 46 suppl. (1986) 4268-4270 Bradford. M. M.: A rapid and se nsitive method for the quantitation ofmicrogram quantities of protein utilizing the principle of protein dye binding. Anal. Biochem. 72 (1976) 248-254 Brihaye. J.: Chronic subdural hematoma. Adv. Neurotraum. 1 (1986) 101 -1 56 Burton . K.: A study oft he conditions and mec hanism of the dip henylamine reaction for colorimetrt c estima tion of deoxyribonucl eic acid. Biochem. J. 62 (1956) 315- 356 Concoiino, G.. R. Giuffre. G. Margiotta. A. Marocchi. C. Conti: Steroid recepto rs in the pathogenesis of chronic subdural hematoma. Clin. Neuropharrnacol. 7 (1984) 343-346 Concolino. G.. G. Liccardo. C. Conti. C.Panfili. R. Giaffr e: Hormones and tumours in central nervous system (CNS): steroid recept ors in primary spinal cord tumours . Neurol. Res . 6 (1984) 121-1 26 Friede. R. L.. W. Schachenmayr: The origin ofsubdural neomemb ranes.lI . Fine structure of neomembranes . Am . J. Pathol. 92 (1978) 69- 84 Gjerris. F.. K. Schmidt: Chronic subdural hematoma. Surgery or mannitoltreatment . J. Neurosurg . 40 (1974) 639-642 Gross. J.. D. A. Moscatelli. D. B. Rijkin:lncreased capillary endothelial cell protease activity in response to angioge nic stimuli in vitro. Proe. Nat!. Aead . Sei. USA80 (19831262 3-2627
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Sex steroid hormones in the patlwgenesis 01 ehren ie su bdural haematoma
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walls of chro nic subdura l hematoma. J. Neurosurg. 48 (1978) 197- 200 Ito. H.. S. Yamamoto. T. Komai , H. Miz ukosh i: Hole ofloea l hyper fibrin olysis in the etiology of chronie subd ura l hematoma. J. Neurosurg. 45 (1976J 26-31 Kawano, N.. K. S uz uki : Presenee of smooth-mus cle cells in the subdura l neomemb ra ne . J. Neuros urg. 54 (1981) 646-651 Koth andaram, P.: Dural liposa rcoma associated with subdural hematoma. Case report . J . Neurosurg. 33 (1970)85-87 Labed ie. E. L.. D. Glooer: Local alter ations of hemostatic-fibrinolytie meehani sms in reformi ng subdura l hematomas. Neurology 25 (1975) 669-67 5 Loeio. F., R. Kivelitz: Chronic subdu ra l haematomas. In: Vtnken . P. J., G. W. Bruyn Ieds.) Handbook of Clinical Neurology, North Holland , Amsterda m 24 (1976) 297-327 Mark wald er. T. M. : Chronic subdural hematomas: a review. J. Neuros urg.54{1981 l 637- 645 Martuza. R. L.. D. C. Miller, D. T. MacLaughlin: Estrogen and progestln bind ing by cytosol and nuclear fractions of huma n meningiomas. J. Neurosurg. 62 (1985) 750- 756 Mira- v-Looez. R.. E. Reich. L. Ossowski: Modulation of plasminogen activator in rodent ma mmary tumors by hor mones and other effectors. Cancer Res. 43 (1983 ) 5467 -5477 Patil, A. A. : Intracrani al meningioma with subdural memb ra ne. Acta Neurochlr. 66 (1982 ) 103- 107 Petr angeli, E.. C. Panfi li, L. Di Giooanni . R. Ten aqiia . V. Toscano , G. Concolin o: Evaluation of and rogen receptors in the homogenate of human benign prostatic hyperp lasia by mean s of extrac tion and excha nge in the presence of sodium molybdate at high conce ntration . J. Lab . Med. 12 (1965) 285-290 Rohr, H. P., H. F. Naej. 0. Hol/iger et al.: The effect of estroge n and stromal growth of the dog pro state. Uro!. Res. 9 (198 1) 201 - 210
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S oto . J., H. Masuzawa. I. Kanazawa. H. Kamitani: Experime nta l
chronic subdura l hema toma Ijapa nesel. Neurotraumat ology (Tokyo) 9(1 986) 201-205 Sato. J.. J. S uzuki: Ultrastruetural observa tions of the caps ule of chronic subdural hemato ma in various clinical stages . J. Neurosurg. 43 1197 5J569- 578 Sica, V.. A. Weisz . A. Petrillo, I. Armetui . G. A. Puca: Assay of total estrogen reeeptor in tissue homogenate an d in tissue fractions by exchange with sodium thiocyan ate at low temperature. Bioche mistr y 20 (l981J686-693 Su suki. J., S. Kom ats u: Estrogen in patients with chronic subdural hemato ma. Surg. Neurol. 8 (1977) 243- 247 Vassal/i, J. /).. 1. Hatnilton. E. Reich: Macro phage plasminogen aetivator: modulation of enzyme prod uction by anti -inflammato ry stero lds. micotic Inhibit ors and cyclic nucleotides . Cell 8 (1976 ) 271-281 Weir, B., P. Gordon : Factors affecting coagulation: fibri nolysis in chronic subd ura l fluid coUections. J. Neurosu rg. 58 (1983) 242-245 Yama shita, T.. R. L. Friede: Why do brid ging veins rup tur e into the virtual subdural space? J. Neuro!' Neurosurg . Psychiat. 47 (98 4) 121-1 27 Yam ash ima, T.. S. Yamamo to, R. L. Friede : The role of endothelial gap junctlons in the enlargementofchro nic subdural hematomas . J . Neurosu rg. 59 (1983 ) 298-3 03
Renato Giuffr e, M. D. Professor and Chief Institute ofNeurosu rgery 2nd State University of Rome via O. Raimondo, I 1·00 173 Rome/l taly
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13
Iv'euroclzirurgia 35 (1992)
Sex steroid hormones in the pathogenesis of chronic subdural haematoma R. I , Giuffre, E. Polm ai . G. Liccardo' , R Sciarrai . R S. Pastore' , G. Concolino' Institute ofNeuros urgery, 2nd State University afRome "Clinica Medica V~ , LaSapienza University ofRome
Summary
In or der 10 verify whet he r horm onal factors could be involved in the path ogenesis of Chronic Subdural Haem atoma (CSDH), bas ed on clinical and epidemiological demonstration of high er ineiden ce of this disease in male patients and particularly in those with high urinary estrogen values , Estradiol (ER) and Progest erone (PR) Receptors were studied in th e Haematoma Exte rn al Membrane (HEM)in 18 mal e and 7 female CSDH patients. Th e observed higher ineidence of ER and PRin male rather th an in female pati ent s (73 % vs 27 % and 72% vs 28% for male a nd female pati ent s resp ectively), and the high er conce ntra tion of ER in Ihe HEM ofmale rather then female pati ent s (55 ± 15 S. E. vs 13 ± 7 S.E. fmol/m g pr otein) suggest that this pathological pro cess, which affects ind ividu als wh ose gonadal activity is quiescent , is mainl y dependent up on hormonallocal effect played hy estrogen compounds on the HEM of the male pati ents. In this sex, in fact, whose tissue s are not usually ada pte d to an estro gen action, th e efTect of estrogens on a responsive tissu e such as the newly-vascularized HEM could lead to an incr eased formation of tissue Plasminogen Activa tor (t-PA), a com pound that , escaping into the subdural collection, could maintain a local hyperfibrinolysis with form ation of Fibrino gen Degrad ation Products (FDP). Ther efor e local hyperfibrinolysis enha nced by ste roid horm ones a nd the subse quent CSDH may perhap s be influenced by the pr ophyl actic or adjuvant treatm ent with inhibitors either of the aromatase activity or of the estrogen action at receptor level.
Sexualhormone in der Pathogenese des ch ronisch en subduralen Hämatoms Um nachzuweisen , daß hormon ale Faktoren bei der Pathogenese des chronische n subduralen Häm atoms [CSDH) eine Rolle spielen - zu vermuten durch den klinischen un d epidemiologischen Hinweis der höh eren lnzidenz bei Männern, inshesonder e be i denen mit höher en Östrogen -Werten im Urin - wu rde n bei 18 männlichen und 7 weiblichen Patient en mit CSDH die Östrogen (ER)- und die Proges teron (PRl-Rezept oren in der äu ßere n Häm atom- Kapsel (HEM) bes tim mt. Die gefundene höher e Rate von ER un d PR hei männlichen gegenüber den weiblichen Patienten (73% vs 27% und 72 % vs 28 %) und die höhe re Konzen tra tion von ER in der HEM (55 ± 15 vs 13 ± 7 fmol/m g Protein) lassen vermuten, daß dieser pathologische Prozeß, der Individu en mit ruhender Gona denfunktion befallt, hauptsäch lich von einem lokalen horm onalen Effekt östrogene r Verbindungen in der HEM der männlichen Pat ienten abhä ngig ist. Bei Mannern ist das Gewebe gewö hnlich nicht an die Östroge n-Effekte adap tiert und bei der Reaktion von Gewebewie der neuvaskularisierten HEMkann es zur erhöhten Bildung von Plasminogen -Faktor (t-PA) komm en. Diese Substanz kann beim Übert ritt in da s Häm atom zu einer lokalen Hyperfibrinolyse mit gleichzeitiger Ernie drigung von Fibrinogene n (FDP) führen. Dahe r kann die lokale Hyper fibrinol yse - verstärkt durch Steroid -Hormo ne und n achfolgend es CSDH - vielleicht durch die prophylaktische oder zusätzliche Beha ndlung mit Antiöstroge nen auf dem Rezeptorenni veau oder mit Antiaromatases ubstanzen .
Key-Words Sub dural haematoma - Steroids - Estradiol - Progest eron e - t-PA- Hyperfibrinolysis
Chro nic sub dura l haematoma (CSDH) has a higher ineidence in male tha n in fema le patients (18), affects male patients with urinary estrogens higher than those found in norm al subjec ts (28); it is more common duringthe 7th decade of life (6, 18, 19 ) i.e. durin g a period of quiescent gonadal activity.
Neurochirurgia 35 (1992) 10 3-1 0 7 © Georg Thieme Verlag Stuttgart · New York
Inside the newly-forrned haematoma exter nal memb ran e (HEM) the ecta tic ca pillaries (10,15,26,32) are believed to be similar to the vascular network of skin in alcoholic cirrhotic patients with elevated estrogen levels (28). Furthermore the fibrinolytic activity a nd tissu e plasmin ogen activator (t-PA) of the haemato ma fluid and the HEM respectively can be compa red to th ose of menstrual bleedin g and ute rine mucosa (13).
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Neurochirurgia 35 (1992)
R.. Giuffre, E. Palme. G. Liccardo. F. S ciarra. F. S. Pas tore. G. Concoltno
Table I Concentration 01 Estrogenreceptors (ER) and Progesterene receptors (PR) inNormal DuraMater Patient
Ag. (y,)
Sex
I
65 32 41 54
2 m
3 4
m
ERe
ERn
PRe
(fmol /mg protein)
(fmol/mg DNA)
(fmol/ mg protein)
33 n.d. 12 50
neg. 56 76 150
43 75 neg.
9
C = cytosol; N = nuclear; N.D. = not determined;neg. = negative
Table 2 Presence ot Estrogen receotcrs (ER) and Progesterene Receptors (PR) in the cytosol and nucleiof HEMofCSDH patients.
ERe PRo ER, PR,
total
male
15/20 (75%) 18/23 (78%) 15/ 22 (68%) 5/8 (63%1
11115 (73%) 13/18 (72%) 10/15 (67%) 3/5 (60%)
female
:..-:..-_ 4/15 (27%) 5118 (28%) 5/15 (33%) 2/5 (40%1
Tabl.3 Concentration of cvtcso! ERand PRinthe HEM ofCSDH patients. male ____
ERe PRe
I
female (fmol/mg of protein ± S. E.)
55± 15 37 + 7
13 ± 7 35 ± 21
S.E. = standard error
In attempt to advanci ng our knowledge in the path ogenesis of CSDH, estrogen receptor (ER)and progesterone receptor (PR) were measured in the HEMofCSDH. Material s and Methods The HEM wa s removed at surgery under local anes thesi a from twen tyfive CSDH patients , eightee n male and seven female {mea nages 69 ± 7 yea rsold and 71 ± 13 yea rs old for male and female r especti velyl. Specimens of dura ma ter Iying a bove the CSDH were sim ultaneously removed from four patients (3 male and 1 female patient ). Four dura mater speci me ns from glioma patients (2 male a nd 2 female) were also studied for comparison. Specime ns of HEM and dura mater were store d at - 70 °C until processed. Cytosol fractions and nuclear extracts we re then obtained with differen tial centrifugation. Methodologica l deta ils ha ve been published elsewhe re (8, 9). Total cytos ol ER (EHe) was measured in 20 specimens an d total nuclear ER (ERn) in 22 specimens of HEM using the method of Sica et al. (27 ). Total cytos ol PR(PRJ was measured in 23 speci mens and total nuclear PR (PRn) in 8 speci mens of HEMusi ng low and high sa lt conce ntration of sodium molybdate respec tively (23) . Only single saturation dose analysis could be performed on acc ount of the small size (80-1 00 mg) of available HEMfragments. After separat ion of free and bound ligands , radioactivitywas meas ured on a Packard 460 CD scintillation spectrometer, protein conce ntration by the Bradford method (5) and DNA conte nt by Burton procedure (7).
The thres hold values were fixed at 3 fentomoles Ifm oll per milligram (mg) of prc te in for cytos ol receptors and at 50 fmoVmg DNA for nuclear receptors .
Results St eroid receptors in normal dura m ater The concentration of'Ell, and ERnwe re similar in the normal dura mater taken from male and fem ale patients . The PRc content , on the contrary, was higher in normal dura mater of the women than in that of the men (Table 1).
Steroid recep tors in HEM Incidence of cytoso l and nuclear ste roid receptors
The inciden ce of ER, was 75% (15/20) an d that of PR, 78 % (18/ 23). Both ER, an d PR, in HEM were more frequent in male rather than in female patients (73 % vs 27%; 72 % vs 28 % for ER, and PR, respectively). Th e incidence ofE R, was 68% (15/ 22) and that orrn, 63 % (5/ 8). ERn was more frequent in the specime ns taken from male ra ther than from fema le patients (67 % vs 33 %) (Table 2). The five PRn we re found in three male and two female patients. Concentration of cytoso l steroid receptors
The concentration of ER, in th e HEM of the male patient s showed mean value of 55 ± 15 S. E. fmoVmg protein with a ra nge from 3 to 104 fmoVmg pr otein. Ther efore the ER, content was slightly higher than that found in the normal dur a mater taken from male patient s (Table 3). Furthermore the ERc values in two specimens of dura mater taken from CSDH patients we re different from those found in the HEM of th e corresponding patients .
The ER, content in the HEM of the four female patients (13 ± 7 S. E. fmoVmg prot ein) was slightly lower than that found in the normal dura mater taken from a femal e patient (33 fmoVmg pr otein), Further more in one female pati ent th e amount of ER, in th e HEM was found compa ra ble to th at measured in the dura mater laying above th e CSDH. The concen tration of PR, in th e HEM of the male patients showed a mean value of 37 ± 7 S. E. frnol/mg protein with range from 5 to 85 fmoVmg protein. The refore , as for ER" also the mean value of PR, in HEM was higher tban that found in norma l dur a mater taken from male patients (Table 3). Two out of the three dura mater sp ecimens lying above the CSDH had PR, values different from those found in HEM of the corre sp onding patients. The concentration of PR, in th e HEM of the fem ale pati ent s sho wed a mean value of 35 ± 21 S. E. frnol/ mg protein with a ra nge from 9 to 91 frnol/mg protein . Therefore the ER, value in HEM was lower than that found in normal dura mater taken from fem ale patients.
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Neurochirurgia 35 (992)
Sex steroid hormones in the palhogenes is oJ ehrenie subdura l haematoma
The mean value of ERn content measured in
the HEM of 10 male patient s was 77 fmoVmg ONA, a value comparable with that obtained in 2 norm al du ra mater, whilst ER, was found only in 1 out of the 3 sa mpies of dura mater laying above CSOH. However the data obtained in these 3 dura mater sampIes were concordant with those measured in the 3 HEM specimens of the corresponding
SUBDUAAL BLEEDING
••
reebscrptjon
il'ljury coagulopathy arrtlcoagulanl lhelapy
QTHERCAUSES
lr nectous osease
/
meningeal eareinomatosis
fibfoblaslic 1 reecnon
NEOMEMBRANE.
NO EVOLUTION jbyct1angep,m,linding)
3
2 inc reased t - PA
NEOPLASTIC EVOLUTION? meningioma
sarcoma
I
c:~) m;"or
patients . Furthermore it is important to underline that negative results we re obtained in 7 out ofth e 22 specimens
examined: 86% (6/7) oft his ER, negati ve HEM specimens were remov ed from male patients.
d
The mean value of'Eli, content measured in the HEM of 5 fema le patients was 99 frnol/mg ONA, higher than that found in one normal dura mater specimen. The dura mater removed from one femal e CSDHpatient was ERn
;"
CSDH
negative as th e corres ponding HEM taken from the same patient.
Fig. l
The measurement of PR n was performed only in 8 HEM specimens, five ofw hich were provided with
Studies perform ed since 1970 demonstrated that the pathog enetic mechanism of a CSOH is represented by the high content of tissue plasmin ogen activator (t-PA) in the ectatic capillaries of HEM, which exudes into the fluid collection, transforming plasminog en into plasmin. This active compound breaks down fibrin with formati on of fibrinogen degradation pro ducts (FOP) and indu ces continuous microbleeding (13, 30).
nuclea r PR.The PR nmeas ured in the dura mater specimens
taken from two CSOH patients was found negative as the PR, in th e HEMof the corres ponding patients . The comparison of the receptor content in
the sampie of HEM of male and fernale CSOIl patients showed that the values of cytosol EHwer e higher in HEM of male than female patients (Table 3); on the contrary, those of nuclear EH were higher in HEM of female than male patients. The values of cytosol PR in the HEM of both sexes were similar.
Sites ofpossible steroid hormones action inthe pathogenesis of CSDH.
The t-PA has the highest value in the HEM (followed by the dur a mater and arachnoidl. whilst th e haematoma content lacks fibrinogen and plasminogen in spite of an extrao rdinary lar ge amount of FOP. This situation is similar to that found in the menstrual blood and
Discussion
It is weil accepted that the primary etiological factor resp onsible for CSOH is the tearin g of corticodura l brid ging veins (31). The bleedin g usually occurs in either a virtual space (25) or a cellular compartment between the dura and the arac hnoid membranes (10), mostly in elderly people becaus e of concomitant cortical atrophy (6). This extravascular blood in some cases can be easily reabsorb ed. whilst in other cases is respon sible for
a fibroblastic reaction leading to the formation of a highly vascularized subdural membrane . Experimental evidence is in favour of a stimulating action on the inner surface of the
dura mater by th e blood fibrin (1). This neomembrane may be found unchanged at aut opsy, whilst in some patient s a local hyperfibrinolysis that interfer es with haemostatic mechanlsms, is respon sible for the formation of a bloody collection betw een the dura and the arachnoid membran es:
the CSOH (14,17). It is interesting to remin d also the reported
formation of a meningioma (2) or of a sarcoma (16) inside the HEM of CSOH patient s, as weil as the ass ociation of a
uterin e mucosa (the former being rich in FOPand the latter rich in t-PA) which ar e affected by horm onal modifications du ring the menstru al cycle. In this respect it has been demonstrated th at the produ ction oft-PAin vitro is stimu lated hy physiological levels of estrogens and further potenti ated by progesteron e (21). It is known that th ese steroids act through their own receptors . For this reason, based on the above men -
tioned epidemiological and clinical data, we decided to see k for the presence of ER and PR in the HEM of CSOH. The results
of
the
present
investigation
support
the
hypothesized pathogenetic role played by the steroid hormones in the formation ofCSOH. The presence of both ER and PR in th e cytosol and nuclea r fractions of th e HEM studied is accompained by a preferential distribution of steroid receptors in
the IlEM of male rath er than female CSOH patients (ER, 73 % vs 27 %; PRc 72 % vs 28 % for male and fema le respec-
tivelyl, Furthe rmore th e higher content of cytosol ER in the HEM of male rather than fema le CSOH patients (55 vs 13 fmol/rng protein) could perhaps account for the sex related higher incidence of CSOH in male rath er than female patients .
meningioma with a newly-formed subdural membrane
without a collection ofblood (22).
The prevalence of ster oid receptors and the higher content of ERin the male rather than female patient s cannot be explained on the basis of the stimulation ofrecep-
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Concentration of nuclea r steroid receptor
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Neurochirurgia 35 (1992)
R.. Giuffre. E. Palma. G. Llccardo. F. Se iarm . F. S. Pastare, G. Conco/ino
tors by eircu lating hormones. CSDH. in fact, is a disease of elderly pat ients, whose gonadal activity is usually quiescent. However it must be taken into eonsideration that some enzyme activities could be responsible for the formation of active metabolites from adrenal and gonadaJpreeursors. This concept is su pported by the increased aromatase aetivity reported in elderly men, whieh can be respons ible for the formation of estrogens from testosterone and androstenedione . It is known that this enzyme aetivity plays an important role in the pathogenesis of hum an ben ign prostatie hyperplasia, which affects elderly men. The refore the reported higher incidence and coneentration of ER in the HEM of male CSDH patients could perh aps be dependent upon the conversion of circulating androgens into est rogen s by the high aromatase activity in the male patients. Furthermo re the tissue response to hormonal stimulation and mai nly to estrogens is more pronounced in male than in fema le vascular network , not because of a lack of progesterone and PR. whieh appear to be uniformly distributed in the two sexes , but because of the different thresholds of response. In women, in fact, vesse ls are usually adapted to high estrogen values . This abnorma l tissue response to estrogens in male patients may aceount for the values of both ER, and PR, of male CSDH pat ients high er than those measured in the norm al dura mat er tak en from male glioma patients usually ofyo unger age than the CSDH pat ients. On the contrary, in the female patients whose tissue are usuall y ada pted to estrogen stimulation. the values of both ER, and PR, in the HEM are lower than those measured in th e normal dur a mater tak en from femal e younger glioma pati ents. As far as the role played by steroid hormones on the pathogenetic mecha nism of CSDH (Fig. j ), estrogens could be involved in the formation of the newlyvaseularized externat membrane, for their action on the neoangiogen ic process (12) and on the mesenchymal cells (24). In this resp ect it is important to note that other ste roid horm ones such as glucocorticoids are known to be related to fibroblasti c rea ctions (29). In addi tion to this dire ct effect, stero id action could also be dependent upon a receptor mediated meehanism based on genomie expression of hormonal stimulatio n. This actio n could lead to the proliferation of the innermos t layer of th e dura mat er and parti cularly to the mesen chymal proliferation ofthe HEM. Moreover ER and PR ha ve been report ed in cra nial an d spinal meningiomas (4. 9, 20). The assoeiation of a men ingeal tumor with a subdural ha emat oma (2. 16) and that of a meningioma with a subdural neomembrane without bloody collection (22) have been report ed too. It is tempting to speculate a possible influe nce of ste roid hormones on both th e lesions . Furthermore the effects of estrogens an d progesterone are more likely to be predominant in mainta ining local hyperfib rinolysis through thei r action on the levels of t-PA. In this respect the presence of ER and PR in the HEM can be consi dered in favour of an horm onal action on this tissue: th e steroid horm ones could play at level ofthe HEM the sa me act ion on t-PA they play at endometrial mueosa level.
The receptor mediated effects of steroids could also explain the higher values of t-PA found in th e HEM than in the dura mater on account ofthe higher content of steroid receptors in the former rather than in the latter. The hormonal effect on t-PA. although not th e primary event leading to the CSDH, can be consi dered as one of the main factors responsible for the fluid collection .
The proposed hormonal pat hogenetic mechanism of CSDH could lead to a medical approac h to CSDH patients, different from those already proposed (3. 11). In fact, the availability of some dru gs with antiaro rnatase activity or with anti estrogen action (able to block the intereonversion of androgens into estrogens or to interfere with estrogens at receptor level] allows to atte mpt a prophylactie therapeutie regimen of patients who experienced a skull injury. in orde r to inhibi t the local hyperfibrinolysis induced by the hor mones, an d eventually to reduce the ineidence of formatio n of CSDH. This medical treatme nt. however, can also be taken into conside ration as adjuvant of CSDH pati ents who underwent surgery. In conclusion, the results of the prese nt study see m to support the hypothesized hormonal effects in th e path ogenesis of a CSDH. The biochemieal data sustai n th e clinical and epidemiologieal investigations quoted in the literature. The action of estrogens and progesterone, through their own receptors, see ms to be particularly relevant at the level ofthe HEM. where they can increa se th e tPAlevels and therefore maintain th e local hyperfibrinolysis . Adjuvant and prophyl actic antihormal treatment may be suggested. References I 2
3 4
5
6 1
I
9
10
11 12
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Sex steroid hormones in the patlwgenesis 01 ehren ie su bdural haematoma
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25
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S oto . J., H. Masuzawa. I. Kanazawa. H. Kamitani: Experime nta l
chronic subdura l hema toma Ijapa nesel. Neurotraumat ology (Tokyo) 9(1 986) 201-205 Sato. J.. J. S uzuki: Ultrastruetural observa tions of the caps ule of chronic subdural hemato ma in various clinical stages . J. Neurosurg. 43 1197 5J569- 578 Sica, V.. A. Weisz . A. Petrillo, I. Armetui . G. A. Puca: Assay of total estrogen reeeptor in tissue homogenate an d in tissue fractions by exchange with sodium thiocyan ate at low temperature. Bioche mistr y 20 (l981J686-693 Su suki. J., S. Kom ats u: Estrogen in patients with chronic subdural hemato ma. Surg. Neurol. 8 (1977) 243- 247 Vassal/i, J. /).. 1. Hatnilton. E. Reich: Macro phage plasminogen aetivator: modulation of enzyme prod uction by anti -inflammato ry stero lds. micotic Inhibit ors and cyclic nucleotides . Cell 8 (1976 ) 271-281 Weir, B., P. Gordon : Factors affecting coagulation: fibri nolysis in chronic subd ura l fluid coUections. J. Neurosu rg. 58 (1983) 242-245 Yama shita, T.. R. L. Friede: Why do brid ging veins rup tur e into the virtual subdural space? J. Neuro!' Neurosurg . Psychiat. 47 (98 4) 121-1 27 Yam ash ima, T.. S. Yamamo to, R. L. Friede : The role of endothelial gap junctlons in the enlargementofchro nic subdural hematomas . J . Neurosu rg. 59 (1983 ) 298-3 03
Renato Giuffr e, M. D. Professor and Chief Institute ofNeurosu rgery 2nd State University of Rome via O. Raimondo, I 1·00 173 Rome/l taly
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Iv'euroclzirurgia 35 (1992)
