Consumption of fibrinolytic proteins in menstrual fluid from women with normal menstrual blood loss.

Abstract

SUMMARY Fibrinolytic proteins in menstrual fluid collected from women with normal menstrual blood loss (<80 ml) were found to be completely exhausted. High levels of t-issue plasminogen activator, fibrin(ogen) degradation products, and plasmin-inhibitor complexes were present, but little fibrinolytically active plasmin remained. No difference was observed between days 1 and 2 of menstruation.The fluidity of menstrual discharge has intrigued investigators for many years,' 2 and the absence of clottable fibrinogen has been attributed to high fibrinolytic activity. The presence of plasminogen activator in endometrial tissue3 and the possibility that an increased level of this enzyme is an aetiological factor in menorrhagia have led to the use of synthetic antifibrinolytic agents to reduce excessive menstrual blood loss.4Since these reports the molecular control of the fibrinolytic enzyme system has been explored in detail.5 6 Plasmin, the major fibrinolytic protease, is generated from the inactive proenzyme plasminogen by the action of the enzyme plasminogen activator, present only in trace amounts in peripheral blood.'8 The action of plasmin on fibrin(ogen) is regulated by the inhibitors fast acting a2-antiplasmin and slow acting a2-macroglobulin.' '0 Fibrin, the primary substrate of plasmin, also plays an important regulatory role: both plasminogen activator and plasminogen bind to fibrin, bringing the proteins into catalytic contact and causing the generation of plasmin activity. In addition, fibrin bound plasmin is protected from a2-antiplasmin inhibition, localising the proteolytic action of plasmin-to the immediate vicinity of the fibrin clot.5 6The recent exploration of the fibrinolytic enzyme system has been facilitated by methodological advances, notably the preparation of antibodies to fibrinolytic proteins and the development of tripeptide chromogenic substrates for functional assays. We have used these techniques to re-examine fibrinolytic proteins in menstrual fluid collected from women with normal menstrual blood loss (less

Comment on “Enhanced Elimination of Perfluorooctanesulfonic Acid by Menstruating Women: Evidence from Population-Based Pharmacokinetic Modeling”

“…The nonblood portion of menstrual fluid, to our knowledge, has an unknown albumin concentration. However, data on the albumin concentration in menstrual fluid supernatant are available and show a concentration the same as in serum . This suggests the nonblood portion of menstrual fluid has the same albumin concentration as serum.…”

“…The corrected mean menstrual fluid volume (MFV) was 86.8 mL. We assumed that the half of the volume that is not blood has an albumin concentration that is the same as in serum . We assumed that the average hematocrit (Hct) in a reproductive-aged woman was 40% .…”

“…The volume of serum equivalent loss is, however, highly variable among women. The distribution of serum equivalent volume per cycle, based on data from Hallberg et al, Fraser et al, and Cederholm-Williams et al, follows a log-normal distribution with a geometric mean of 49.9 mL and a geometric standard deviation of 2.27 mL (range, 8–872). ,, …”

Development of an immunoassay for the differentiation of menstrual blood from peripheral blood

“…On the other hand, menstrual blood does not clot due to the high presence of plasmin which degrades fibrinogen [17,37]. It also contains little to no prothrombin [11].…”

Menstrual cycle characteristics as determinants of plasma concentrations of perfluoroalkyl substances (PFASs) in the Norwegian Mother and Child Cohort (MoBa study)

“…From a biological standpoint, PFASs are found at the highest levels in body compartments with high concentrations of proteins, such as the blood and liver (reviewed in Conder et al, 2008). Most of the PFASs in plasma are bound to albumin (Han et al, 2003; Jones et al, 2003) and menstrual fluid contains high levels of albumin (Cederholm-Williams et al, 1984). Further evidence implicating menstrual cycles as a potential elimination route for PFASs are epidemiologic studies finding higher concentrations of PFASs in postmenopausal women compared with women who are still menstruating (Knox et al, 2011; Taylor et al, 2014), and lower concentrations in premenopausal women with menorrhagia (Zhou 2017).…”