Role of the small proteoglycan bikunin in human reproduction

PURPOSE

Female reproductive events, including ovulation, menstruation, implantation, and delivery, are physiologically characterized by deep tissue remodeling and display hallmark signs of inflammation. This review discusses the pleiotropic roles played by bikunin in human reproduction.

METHODS

A comprehensive literature search of the Medline/PubMed database was performed on the following topics: bikunin structure, roles in pathophysiological conditions and involvement in human reproduction, and usefulness as a marker of gestational complications or as a drug to improve pregnancy outcomes.

RESULTS

Bikunin is a small chondroitin sulfate proteoglycan found in blood, urine, and amniotic and cerebrospinal fluids, known for its anti-inflammatory and anti-proteolytic activities. Its levels are usually low, but they can increase several-fold in both acute and chronic inflammatory diseases. Bikunin plays key roles in reproductive events, such as cumulus-oocyte complex formation, pregnancy, and delivery. Its levels have been associated with the most common pregnancy complications such as preterm delivery, pre-eclampsia, and gestational diabetes mellitus. Finally, its intravaginal administration has been reported to reduce the risk of preterm delivery and to improve neonatal outcomes.

CONCLUSIONS

Because of its pleiotropic roles in several reproductive events and its association with some life-threatening pathological conditions of pregnancy, bikunin may represent a non-invasive marker for improving follow-up and early diagnosis. Studies showing its usefulness as a drug for reducing the risk of preterm delivery and improving neonatal outcomes have yielded interesting results that deserve to be investigated through further research.

Vaginal lactoferrin administration before genetic amniocentesis decreases amniotic interleukin-6 levels

AIM

To verify the eventual efficacy of lactoferrin (LF), an iron-binding glycoprotein, to decrease the amniotic concentration of interleukin-6 (IL-6).

METHODS

We prospectively enrolled 60 Caucasian patients at the 16th week of their singleton physiological gestation. A vaginal compound containing 300 mg of LF was administered randomly 4 or 12 h prior to amniocentesis, as to obtain 3 groups: A, 20 untreated patients; B, 20 treated 4 h before amniocentesis; C, 20 treated 12 h before amniocentesis.

RESULTS

A normal karyotype was registered in all cases. The comparison of the distribution of IL-6 among the 3 groups showed a highly significant difference (p = 0.001). The difference between mean values of group B and both groups C and A was shown to be highly significant (p = 0.006 and p = 0.03, respectively). In contrast, there was no significant difference between mean values of groups A and C.

CONCLUSION

Vaginal LF administration decreases amniotic IL-6 concentration. We therefore suggest that the glycoprotein may exert a protective role against ominous pregnancy complications linked to an increased level of the cytokine, such as abortion secondary to amniocentesis.

The association between proinflammatory cytokine polymorphisms and cerebral palsy in very preterm infants

Cerebral palsy (CP) is a nonprogressive motor disorder caused by white matter damage in the developing brain and is often accompanied with cognitive and sensory disabilities. The risk of CP is higher among infants born preterm than in more mature infants. Intrauterine infection/inflammation, activation of the cytokine network and elevated levels of proinflammatory cytokines in neonatal blood or in amniotic fluid to which the preterm infant is exposed, has been identified as the most common cause of preterm delivery, periventricular leukomalacia (PVL) and CP. The aim of our study was to evaluate the possible association of four TNFα promoter single nucleotide polymorphisms (SNPs) (-1031 T/C, -857 C/T, -308 G/A and -238 G/A), two IL1β SNPs (-511 C/T and +3954 C/T) and one IL6 (-174 C/G) polymorphism with susceptibility to CP in very preterm infants. Statistically significant association between TNFα -1031 T/C high expression genotypes (TC and CC) (OR, 2.339; p=0.016) as well as between TNFα -1031 C high expression allele (OR, 2.065; p=0.013) and risk of CP was observed. In addition, statistically significant association was found between TNFα TC, CC, GG, GG -1031/-857/-308/-238 genotypes combination (OR, 3.286; p=0.034) and risk of CP. Statistically significant association between IL1β TT, CC -511/+3954 genotypes combination and risk of CP (OR, 4.000; p=0.027) was also found. In CP patients with cystic PVL (cPVL) statistically significant association was found between TNFα -1031 T/C high expression genotypes (TC and CC) (OR, 2.361; p=0.038), IL1β -511 C/T high expression genotype TT (OR, 3.215; p=0.030) as well as IL1β -511 T high expression allele (OR, 1.956; p=0.019) and risk of CP. Statistically significant association was also found in patients with cPVL between TNFα TC, CC, GG, GG -1031/-857/-308/-238 genotypes combination (OR, 4.107; p=0.024), as well as IL1β TT, CC -511/+3954 genotypes combination (OR, 7.333; p=0.005) and risk of CP. Our results suggest the role of TNFα and IL1β polymorphisms which have previously been associated with higher circulating levels of these cytokines in genetic susceptibility to white matter damage and consequently CP in very preterm infants.