N. Lucarini

Testosterone aromatization in rat brain is modulated by social environment.

Abstract The influence of socio-sexual deprivation on in vitro testosterone metabolism in the brain and on plasma testosterone and estradiol concentrations, was studied in male and female Sprague-Dawley rats. Androstenedione and estradiol were isolated as metabolites of testosterone in rat brain. Biosynthesis of estradiol from testosterone was increased in all the groups of deprived males and only in the group of contact deprived females; biosynthesis of androstenedione from testosterone was increased in the group of unisexually reared males and was decreased in the group of unisexually reared females. Furthermore plasma concentrations of testosterone and estradiol were measured: testosterone showed a significant decrease in all the groups of deprived animals both males and females; estradiol also showed a significant decrease after different types of deprivation. These findings suggest that brain aromatization, which has a relevant importance in the control of sexual behavior, can be influenced by a complex pattern of different stimuli, which bear information on the social environment. Plasma testosterone, which was influenced by social environment, was inversely correlated with brain aromatization.

Haptoglobin genotype and natural fertility in humans

OBJECTIVE To study the possible relation between human natural fertility and haptoglobin (Hp) genotype. DESIGN Prospective study. SETTING Maternity departments of local hospitals in two Italian localities. PATIENT(S) Healthy women who had just given birth in the maternity departments of two local hospitals (n = 679). INTERVENTION(S) Venous blood collection for determination of Hp genotype with the use of starch gel electrophoresis of hemoglobin-supplemented serum. MAIN OUTCOME MEASURE(S) Distribution of Hp genotypes in relation to age of puerperae. RESULT(S) In both populations, the proportion of young mothers was much higher among women who were homozygous for the Hp*1 allele (the Hp*1/*1 genotype) than among women who had other Hp genotypes. In addition, the proportion of multiparous women among the older mothers was higher among those with the Hp*1/*1 genotype than among those with other Hp genotypes. CONCLUSION(S) The data suggest that women with the Hp*1/*1 genotype reproduce at an earlier age and have higher natural fertility potential than women with other Hp genotypes.

Phosphotyrosine protein phosphatase and diabetic pregnancy: an association between low molecular weight acid phosphatase and degree of glycemic control

Low molecular weight acid phosphatase encoded by the highly polymorphic locus ACP 1 is a member of the protein-tyrosin phosphatase family (PTPases) which plays an essential role in the control of receptor signalling through phosphotyrosine pathways. Recent experiments have shown that purified rat liver ACP, corresponding to human ACP1, is able to hydrolyze a phosphotyrosine-containing synthetic peptide corresponding to the 1146–1158 sequence of the human insulin receptor, and shows a high affinity for it. This prompted us to analyze the degree of glycemic control in relation to ACP1 genetic variability in a sample of 214 diabetic pregnant women including IDDM, NIDDM and gestational diabetes. The ACP1 genotype was also determined in 482 non-diabetic pregnant women. In diabetic women glycemic levels in thelast trimester of pregnancy appear to be significantly associated with the ACP1 genotype, and correlated positively with ACP1 enzymatic activity. The data suggest that quantitative variations of ACP1 may influence the clincal mainifestations of diabetic disorders, and call for further studies on the role of this enzyme in the modulation of insulin-receptor phosphotyrosine pathways.

Inflammatory bowel disease: Are there gender differences in the genetics of signal transduction? A preliminary study of cytosolic low molecular weight protein tyrosine phosphatase.

The phenotype of cytosolic Low Molecular Weight Protein Tyrosine Phosphatase (cLMWPTP or ACP1), an enzyme involved in signal transduction of insulin, PDGF and T-cell receptors, has been determined in 71 patients with Crohns Disease (CD: 37 males and 34 females), 49 patients with Ulcerative Colitis (UC: 27 males and 22 females) and 358 consecutive newborns (194 males and 164 females). cLMWPTP phenotypes showing a high concentration of F isoforms are associated with CD in females and with UC in males. Since PTPases counteract the effects of protein tyrosines kinases, a high concentration of F isoform of cLMWPTP may influence the mucosal response to pathogenic factors, increasing susceptibility to CD in females and to UC in males.

Adenosine Deaminase and Human Reproduction: A Comparative Study of Fertile Women and Women with Recurrent Spontaneous Abortion

PROBLEM: We have investigated the possible role of adenosine deaminase (ADA) genetic polymorphism in human fertility through a comparative study of couples with recurrent spontaneous abortion (RSA) and healthy puerperae.

Erythrocyte acid phosphatase (ACP1) activity

SummaryErythrocyte acid phosphatase (ACP1) activity was determined in the absence of modulators and in the presence of either adenosine or inosine as modulators in 154 samples of red blood cells collected from adult donors. Adenosine and inosine showed modulating effects (activation), that were genotype dependent in the allele order pb<pa<pc; the activation by inosine was much higher than by adenosine. The modulating effect was dependent on adenosine deaminase (ADA) genotype: In carriers of ADA2 allele the activation with ACP1 phenotype A was lower and that with phenotypes CA and CB was higher than in ADA1/ADA1 subjects. In addition, the basic ACP1 activity (i.e., without modulators) also appeared to be dependent on ADA genotype: The lowest ACP1 activity was observed in A and BA subjects carrying the ADA2 allele. Since the deamination of adenosine to inosine associated with ADA2-1 phenotype is slower than that associated with ADA1, the interaction of ADA on ACP1 activity may in fact be explained by a lower intracellular concentration of inosine in ADA2 carriers and, therefore, by a lower modulating effect of this on acid phosphatase activity.

Age- and gender-specific epistasis between ADA and TNF-α influences human life-expectancy.

Aging is a complex phenotype with multiple determinants but a strong genetic component significantly impacts on survival to extreme ages. The dysregulation of immune responses occurring with increasing age is believed to contribute to human morbidity and mortality. Conversely, some genetic determinants of successful aging might reside in those polymorphisms for the immune system genes regulating immune responses. Here we examined the main effects of single loci and multi-locus interactions to test the hypothesis that the adenosine deaminase (ADA) and tumor necrosis factor alpha (TNF-α) genes may influence human life-expectancy. ADA (22G>A, rs73598374) and TNF-α (-308G>A, rs1800629; -238G>A, rs361525) functional SNPs have been determined for 1071 unrelated healthy individuals from Central Italy (18-106 years old) divided into three gender-specific age classes defined according to demographic information and accounting for the different survivals between sexes: for men (women), the first class consists of individuals<66 years old (<73 years old), the second class of individuals 66-88 years old (73-91 years old), and the third class of individuals>88 years old (>91 years old). Single-locus analysis showed that only ADA 22G>A is significantly associated with human life-expectancy in males (comparison 1 (age class 2 vs. age class 1), O.R. 1.943, P=0.036; comparison 2 (age class 3 vs. age class 2), O.R. 0.320, P=0.0056). Age- and gender-specific patterns of epistasis between ADA and TNF-α were found using Generalized Multifactor Dimensionality Reduction (GMDR). In comparison 1, a significant two-loci interaction occurs in females between ADA 22G>A and TNF-α -238G>A (Sign Test P=0.011). In comparison 2, both two-loci and three-loci interaction are significant associated with increased life-expectancy over 88 years in males. In conclusion, we report that a combination of functional SNPs within ADA and TNF-α genes can influence life-expectancy in a gender-specific manner and that males and females follow different pathways to attain longevity.

ACP1 and human adaptability 2. Association with season of conception

Abstract We have studied the pattern of association between the season of conception and cytosolic low molecular weight phosphotyrosine phosphatase (ACP1) genetic polymorphism in 329 consecutively newborn infants from the population of Penne and 361 consecutively newborn infants from the population of Rome. In addition, 329 mothers were studied in the population of Penne. A concordant, highly significant association was observed in the two populations between ACP1 parameters and the season of conception of newborn infants. The total activity of ACP1 shows a minimum in infants conceived in January–February and a maximum in those conceived at the end of the solar year. Analysis of the joint mother-newborn ACP1 distribution in relation to the season of fertilisation has shown that among mothers carrying ACP1*A (the allele showing the lowest activity), the proportion of newborns carrying this allele is higher in those conceived in the first months of the year than in those conceived subsequently. Since ACP1 probably functions as a phosphotyrosine phosphatase and as a flavin mononucleotide phosphatase, low activity could enhance the metabolic rate and would be advantageous in a cold environment. The cycle of variation of ACP1 in infants follows the cycle of solar illumination. It is possible that individuals who have a genetic background allowing them to adapt easily and readily to seasonal demand are more successful in reproducing themselves. The population of zygotes conceived in a given season would therefore reproduce the pattern of gene combination more fit for that season.

The Genetics of Signal Transduction and the Feto-Maternal Relationship. A Study of Cytosolic Low Molecular Weight Phosphotyrosine Phosphatase

Intracellular kinases mediate positive signalling from surface receptors by phosphorylating critical target proteins whereas phosphatases inhibit this process. Differential phosphatase activity at the feto-maternal interface could determine the appropriate relative growth and development on each side of the placenta. The highly polymorphic cytosolic low molecular weight phosphotyrosine-phosphatase (ACP1-cLMWPTPase) has been studied in 170 women who had at least two consecutive spontaneous abortions along with their husbands and in 352 normal puerperae along with their newborn babies. Symmetry analysis of joint wife/husband and mother/infant distribution suggests that when ACP1 activity is lower in the mother than in either her aborted fetus or her child, the probability of abortion is higher and the survival to term is lower as compared to pairs in which the ACP1 activity is higher in the mother than in her fetus. Further analysis has shown that the effect is due to S isoform: i.e. a high mother/fetus S isoform ratio favours intrauterine survival. Analysis of gestational duration and birth weight suggests that a high ACP1 maternal activity coupled with a low or moderate fetal activity favour fetal growth and developmental maturation. The present data indicate that maternal-fetal genetic differences in signal transduction could contribute significantly to variability of intrauterine developmental parameters and to pathological manifestation of pregnancy.

Interaction between ABO blood groups and ADA genetic polymorphism during intrauterine life

A total of 203 couples with unexplained habitual abortions and 364 consecutive normal puerperae along with their live-born babies were studied. The analysis of wife-husband joint ABO blood group distribution in couples with habitual abortion showed an excess of A incompatible mating type and a defect of B incompatible type as compared with expected proportions assuming random mating. The joint wife-husband ABO blood group distribution was further analysed in relation to the adenosine deaminase (ADA) genotype. A defect of O-A and A-O couples when the wife carries the ADA*1/*1 genotype and the husband carries the ADA*2 allele, and a defect of O-O and A-A when the wife carries the ADA*2 allele were observed. In the sample of normal puerperae, analysis of the joint mother-newborn ABO distribution in relation to the ADA genotype showed a pattern similar to that observed in couples with habitual abortion, i.e. there is a defect of O-A and A-O when the mother carries the ADA*1/*1 genotype and the newborn carries the ADA*2 allele and a defect of O-O and A-A types when the mother carries the ADA*2 allele. Altogether the data suggest an early loss of O-A and A-O zygotes when they carry the ADA*2 allele and an early loss of O-O and A-A zygotes when the mother carries the ADA*2 allele resulting in a deficit of these zygotic classes among both spontaneously aborted fetuses and live-born infants. The pattern of association observed in the mother-fetus type O-A (incompatible according to conventional terminology) appears similar to that observed for the reciprocal A-O type (compatible according to conventional terminolgy). Therefore strictly conventional immunological mechanisms cannot explain the whole pattern of associations. Cell to cell interactions involving ABO antigens may have an important role at implantation: ADA, through the control of local adenosine concentration, could modulate these interactions influencing the probability of successful implantation.