Continuity of Psychopathology Throughout Adolescence and Young Adulthood

OBJECTIVE

This study tested two opposing hypotheses on the continuity of psychopathology throughout adolescence and young adulthood; differentiation versus dynamic mutualism. Differentiation predicts that co-occurrence decreases, while dynamic mutualism predicts that co-occurrence increases due to causal interactions amongst mental health problems.

METHOD

Using data from the Dutch TRacking Adolescents' Individual Lives Survey (n = 2228, 51% female), we studied the development of self-reported internalizing, externalizing, and attention problems at ages 11 to 26 across six waves. Random-intercept cross-lagged panel modeling was employed to distinguish within-person development from stable between-person processes.

RESULTS

Large stable between-person associations indicated that adolescents with internalizing problems tended to have both externalizing and attention problems as well. On a within-person level, mental health problems showed partial stability and strong cross-sectional co-occurrence. Within-wave associations of internalizing with externalizing or attention problems decreased between age 11 and 16 years, after which they increased again. Little heterotypic continuity was found: age 11 externalizing predicted age 13 attention, which in turn predicted age 16 externalizing problems, and internalizing predicted externalizing problems across ages 22 to 26. Findings were similar for males and females.

CONCLUSIONS

Our findings suggest co-occurrence decreases during early and middle adolescence, supporting differentiation. While co-occurrence increased again into young adulthood, this could not be labeled as dynamic mutualism because little evidence for heterotypic continuity was found in this phase of life. The strong stable links between internalizing, externalizing, and attention problems stress the importance of targeting these mental health problems and their shared risk factors together.

Quality over quantity: A transactional model of social withdrawal and friendship development in late adolescence

The aim of this study was to test a longitudinal, transactional model that describes how social withdrawal and friendship development are interrelated in late adolescence, and to investigate if post‐secondary transitions are catalysts of change for highly withdrawn adolescents’ friendships. Unilateral friendship data of 1,019 adolescents (61.3% female, 91% Dutch‐origin) from the Tracking Adolescents’ Individual Lives Survey (TRAILS) cohort were collected five times from ages 17 to 18 years. Social withdrawal was assessed at 16 and 19 years. The transactional model was tested within a Structural Equation Modeling framework, with intercepts and slopes of friendship quantity, quality, and stability as mediators and residential transitions, education transitions, and sex as moderators. The results confirmed the presence of a transactional relation between withdrawal and friendship quality. Whereas higher age 16 withdrawal predicted having fewer, lower‐quality, and less‐stable friendships, only having lower‐quality friendships, in turn, predicted higher age 19 withdrawal, especially in girls. Residential transitions were catalysts of change for highly withdrawn youth's number of friends: higher withdrawal predicted a moderate increase in number of friends for adolescents who relocated, and no change for those who made an educational transition or did not transition. Taken together, these results indicate that the quality of friendships—over and above number of friends and the stability of those friendships—is particularly important for entrenching or diminishing withdrawal in late adolescence, and that relocating provides an opportunity for withdrawn late adolescents to expand their friendship networks.

Robust longitudinal multi-cohort results: The development of self-control during adolescence

Longitudinal data from multiple cohorts may be analyzed by Bayesian research synthesis. Here, we illustrate this approach by investigating the development of self-control between age 13 and 19 and the role of sex therein in a multi-cohort, longitudinal design. Three Dutch cohorts supplied data: the Netherlands Twin Register (NTR; N = 21,079), Research on Adolescent Development and Relationships-Young (RADAR-Y; N = 497), and Tracking Adolescents' Individual Lives Survey (TRAILS; N = 2229). Self-control was assessed by one measure in NTR and RADAR-Y, and three measures in TRAILS. In each cohort, we evaluated evidence for competing informative hypotheses regarding the development of self-control. Subsequently, we aggregated this evidence over cohorts and measures to arrive at a robust conclusion that was supported by all cohorts and measures. We found robust evidence for the hypothesis that on average self-control increases during adolescence (i.e., maturation) and that individuals with lower initial self-control often experience a steeper increase in self-control (i.e., a pattern of recovery). From self-report, boys have higher initial self-control levels at age 13 than girls, whereas parents report higher self-control for girls.

Testing differential susceptibility: Plasticity genes, the social environment, and their interplay in adolescent response inhibition

OBJECTIVES

Impaired inhibitory control is a key feature of attention-deficit/hyperactivity disorder (ADHD). We investigated gene-environment interaction (GxE) as a possible contributing factor to response inhibition variation in context of the differential susceptibility theory. This states individuals carrying plasticity gene variants will be more disadvantaged in negative, but more advantaged in positive environments.

METHODS

Behavioural and neural measures of response inhibition were assessed during a Stop-signal task in participants with (N = 197) and without (N = 295) ADHD, from N = 278 families (age M = 17.18, SD =3.65). We examined GxE between candidate plasticity genes (DAT1, 5-HTT, DRD4) and social environments (maternal expressed emotion, peer affiliation).

RESULTS

A DRD4 × Positive peer affiliation interaction was found on the right fusiform gyrus (rFG) activation during successful inhibition. Further, 5-HTT short allele carriers showed increased rFG activation during failed inhibitions. Maternal warmth and positive peer affiliation were positively associated with right inferior frontal cortex activation during successful inhibition. Deviant peer affiliation was positively related to the error rate.

CONCLUSIONS

While a pattern of differential genetic susceptibility was found, more clarity on the role of the FG during response inhibition is warranted before firm conclusions can be made. Positive and negative social environments were related to inhibitory control. This extends previous research emphasizing adverse environments.

Novel genetic loci associated with hippocampal volume

The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (rg=-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness.

Risk factors for comorbid oppositional defiant disorder in attention-deficit/hyperactivity disorder

Oppositional defiant disorder (ODD) is highly prevalent in attention-deficit/hyperactivity disorder (ADHD). Individuals with both ADHD and ODD (ADHD + ODD) show a considerably worse prognosis compared with individuals with either ADHD or ODD. Therefore, identification of risk factors for ADHD + ODD is essential and may contribute to the development of (early) preventive interventions. Participants were matched for age, gender, and ADHD-subtype (diagnostic groups), and did not differ in IQ. Predictors included pre- and perinatal risk factors (pregnancy duration, birth weight, maternal smoking during pregnancy), transgenerational factors (parental ADHD; parental warmth and criticism in diagnostic groups), and postnatal risk factors (parental socioeconomic status [SES], adverse life events, deviant peer affiliation). Three models were assessed, investigating risk factors for ADHD-only versus controls (N = 86), ADHD + ODD versus controls (N = 86), and ADHD + ODD versus ADHD-only (N = 90). Adverse life events and parental ADHD were risk factors for both ADHD + ODD and ADHD-only, and more adverse life events were an even stronger risk factor for comorbid ODD compared with ADHD-only. For ADHD + ODD, but not ADHD-only, parental criticism, deviant peer affiliation, and parental SES acted as risk factors. Maternal smoking during pregnancy acted as minor risk factor for ADHD-only, while higher birth weight acted as minor risk factor for ADHD + ODD. No effects of age were present. Findings emphasise the importance of these factors in the development of comorbid ODD. The identified risk factors may prove to be essential in preventive interventions for comorbid ODD in ADHD, highlighting the need for parent-focused interventions to take these factors into account.

Novel genetic loci underlying human intracranial volume identified through genome-wide association

Intracranial volume reflects the maximally attained brain size during development, and remains stable with loss of tissue in late life. It is highly heritable, but the underlying genes remain largely undetermined. In a genome-wide association study of 32,438 adults, we discovered five previously unknown loci for intracranial volume and confirmed two known signals. Four of the loci were also associated with adult human stature, but these remained associated with intracranial volume after adjusting for height. We found a high genetic correlation with child head circumference (ρgenetic = 0.748), which indicates a similar genetic background and allowed us to identify four additional loci through meta-analysis (Ncombined = 37,345). Variants for intracranial volume were also related to childhood and adult cognitive function, and Parkinson's disease, and were enriched near genes involved in growth pathways, including PI3K-AKT signaling. These findings identify the biological underpinnings of intracranial volume and their link to physiological and pathological traits.

Developmentally Sensitive Interaction Effects of Genes and the Social Environment on Total and Subcortical Brain Volumes

Smaller total brain and subcortical volumes have been linked to psychopathology including attention-deficit/hyperactivity disorder (ADHD). Identifying mechanisms underlying these alterations, therefore, is of great importance. We investigated the role of gene-environment interactions (GxE) in interindividual variability of total gray matter (GM), caudate, and putamen volumes. Brain volumes were derived from structural magnetic resonance imaging scans in participants with (N = 312) and without ADHD (N = 437) from N = 402 families (age M = 17.00, SD = 3.60). GxE effects between DAT1, 5-HTT, and DRD4 and social environments (maternal expressed warmth and criticism; positive and deviant peer affiliation) as well as the possible moderating effect of age were examined using linear mixed modeling. We also tested whether findings depended on ADHD severity. Deviant peer affiliation was associated with lower caudate volume. Participants with low deviant peer affiliations had larger total GM volumes with increasing age. Likewise, developmentally sensitive GxE effects were found on total GM and putamen volume. For total GM, differential age effects were found for DAT1 9-repeat and HTTLPR L/L genotypes, depending on the amount of positive peer affiliation. For putamen volume, DRD4 7-repeat carriers and DAT1 10/10 homozygotes showed opposite age relations depending on positive peer affiliation and maternal criticism, respectively. All results were independent of ADHD severity. The presence of differential age-dependent GxE effects might explain the diverse and sometimes opposing results of environmental and genetic effects on brain volumes observed so far.

Adolescent behavioral and neural reward sensitivity: a test of the differential susceptibility theory

Little is known about the causes of individual differences in reward sensitivity. We investigated gene-environment interactions (GxE) on behavioral and neural measures of reward sensitivity, in light of the differential susceptibility theory. This theory states that individuals carrying plasticity gene variants will be more disadvantaged in negative, but more advantaged in positive environments. Reward responses were assessed during a monetary incentive delay task in 178 participants with and 265 without attention-deficit/hyperactivity disorder (ADHD), from N=261 families. We examined interactions between variants in candidate plasticity genes (DAT1, 5-HTT and DRD4) and social environments (maternal expressed emotion and peer affiliation). HTTLPR short allele carriers showed the least reward speeding when exposed to high positive peer affiliation, but the most when faced with low positive peer affiliation or low maternal warmth. DAT1 10-repeat homozygotes displayed similar GxE patterns toward maternal warmth on general task performance. At the neural level, DRD4 7-repeat carriers showed the least striatal activation during reward anticipation when exposed to high maternal warmth, but the most when exposed to low warmth. Findings were independent of ADHD severity. Our results partially confirm the differential susceptibility theory and indicate the importance of positive social environments in reward sensitivity and general task performance for persons with specific genotypes.

A follow-up study of maternal expressed emotion toward children with Attention-Deficit/Hyperactivity Disorder (ADHD): relation with severity and persistence of ADHD and comorbidity

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) is associated with conflicted parent-child relationships. The underlying mechanisms of this association are not yet fully understood. We investigated the cross-sectional and longitudinal relationships between externalizing psychopathology in children with ADHD, and expressed emotion (EE; warmth and criticism) and psychopathology in mothers.

METHOD

In this 6-year follow-up study, 385 children with an ADHD combined subtype were included at baseline (mean, 11.5 years, 83.4% male), of which 285 children (74%) were available at follow-up (mean, 17.5 years, 83.5% male). At both time points, measures of child psychopathology (i.e., ADHD severity, oppositional, and conduct problems), maternal EE, and maternal psychopathology (i.e., ADHD and affective problems) were obtained.

RESULTS

EE was not significantly correlated over time. At baseline, we found a nominally negative association (p ≤ .05) between maternal warmth and child ADHD severity. At follow-up, maternal criticism was significantly associated with child oppositional problems, and nominally with child conduct problems. Maternal warmth was nominally associated with child oppositional and conduct problems. These associations were independent of maternal psychopathology. No longitudinal associations were found between EE at baseline and child psychopathology at follow-up, or child psychopathology at baseline and EE at follow-up.

CONCLUSIONS

The results support previous findings of cross-sectional associations between parental EE and child psychopathology. This, together with the finding that EE was not stable over 6 years, suggests that EE is a momentary state measure varying with contextual and developmental factors. EE does not appear to be a risk factor for later externalizing behavior in children with ADHD.

The co-occurrence of autism spectrum disorder and attention-deficit/hyperactivity disorder symptoms in parents of children with ASD or ASD with ADHD

BACKGROUND

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) share about 50-72% of their genetic factors, which is the most likely explanation for their frequent co-occurrence within the same patient or family. An additional or alternative explanation for the co-occurrence may be (cross-)assortative mating, e.g., the tendency to choose a partner that is similar or dissimilar to oneself. Another issue is that of parent-of-origin effect which refers to the possibility of parents differing in the relative quantity of risk factors they transmit to the offspring. The current study sets out to examine (cross-)assortative mating and (cross-)parent-of-origin effects of ASD and ADHD in parents of children with either ASD or ASD with ADHD diagnosis.

METHODS

In total, 121 families were recruited in an ongoing autism-ADHD family genetics project. Participating families consisted of parents and at least one child aged between 2 and 20 years, with either autistic disorder, Asperger disorder or PDD-NOS, and one or more biological siblings. All children and parents were carefully screened for the presence of ASD and ADHD.

RESULTS

No correlations were found between maternal and paternal ASD and ADHD symptoms. Parental ASD and ADHD symptoms were predictive for similar symptoms in the offspring, but with maternal hyperactive-impulsive symptoms, but not paternal symptoms, predicting similar symptoms in daughters. ASD pathology in the parents was not predictive for ADHD pathology in the offspring, but mother's ADHD pathology was predictive for offspring ASD pathology even when corrected for maternal ASD pathology.

CONCLUSIONS

Cross-assortative mating for ASD and ADHD does not form an explanation for the frequent co-occurrence of these disorders within families. Given that parental ADHD is predictive of offspring' ASD but not vice versa, risk factors underlying ASD may overlap to a larger degree with risk factors underlying ADHD than vice versa. However, future research is needed to clarify this issue.

Either Kras activation or Pten loss similarly enhance the dominant-stable CTNNB1-induced genetic program to promote granulosa cell tumor development in the ovary and testis

WNT, RAS or phosphoinositide 3-kinase signaling pathways control specific stages of ovarian follicular development. To analyze the functional interactions of these pathways in granulosa cells during follicular development in vivo, we generated specific mutant mouse models. Stable activation of the WNT signaling effector β-catenin (CTNNB1) in granulosa cells results in the formation of premalignant lesions that develop into granulosa cell tumors (GCTs) spontaneously later in life or following targeted deletion of the tumor suppressor gene Pten. Conversely, expression of oncogenic KRAS(G12D) dramatically arrests proliferation, differentiation and apoptosis in granulosa cells, and consequently, small abnormal follicle-like structures devoid of oocytes accumulate in the ovary. Because of the potent anti-proliferative effects of KRAS(G12D) in granulosa cells, we sought to determine whether KRAS(G12D) would block precancerous lesion and tumor formation in follicles of the CTNNB1-mutant mice. Unexpectedly, transgenic Ctnnb1;Kras-mutant mice exhibited increased GC proliferation, decreased apoptosis and impaired differentiation and developed early-onset GCTs leading to premature death in a manner similar to the Ctnnb1;Pten-mutant mice. Microarray and reverse transcription-PCR analyses revealed that gene regulatory processes induced by CTNNB1 were mostly enhanced by either KRAS activation or Pten loss in remarkably similar patterns and degree. The concomitant activation of CTNNB1 and KRAS in Sertoli cells also caused testicular granulosa cell tumors that showed gene expression patterns that partially overlapped those observed in GCTs of the ovary. Although the mutations analyzed herein have not yet been linked to adult GCTs in humans, they may be related to juvenile GCTs or to tumors in other tissues where CTNNB1 is mutated. Importantly, the results provide strong evidence that CTNNB1 is the driver in these contexts and that KRAS(G12D) and Pten loss promote the program set in motion by the CTNNB1.

Molecular and functional characteristics of ovarian surface epithelial cells transformed by KrasG12D and loss of Pten in a mouse model in vivo

Ovarian cancer is a complex and deadly disease that remains difficult to detect at an early curable stage. Furthermore, although some oncogenic (Kras, Pten/PI3K and Trp53) pathways that are frequently mutated, deleted or amplified in ovarian cancer are known, how these pathways initiate and drive specific morphological phenotypes and tumor outcomes remain unclear. We recently generated Pten(fl/fl); Kras(G12D); Amhr2-Cre mice to disrupt the Pten gene and express a stable mutant form of Kras(G12D) in ovarian surface epithelial (OSE) cells. On the basis of histopathologic criteria, the mutant mice developed low-grade ovarian serous papillary adenocarcinomas at an early age and with 100% penetrance. This highly reproducible phenotype provides the first mouse model in which to study this ovarian cancer subtype. OSE cells isolated from ovaries of mutant mice at 5 and 10 weeks of age exhibit temporal changes in the expression of specific Mullerian epithelial marker genes, grow in soft agar and develop ectopic invasive tumors in recipient mice, indicating that the cells are transformed. Gene profiling identified specific mRNAs and microRNAs differentially expressed in purified OSE cells derived from tumors of the mutant mice compared with wild-type OSE cells. Mapping of transcripts or genes between the mouse OSE mutant data sets, the Kras signature from human cancer cell lines and the human ovarian tumor array data sets, documented significant overlap, indicating that KRAS is a key driver of OSE transformation in this context. Two key hallmarks of the mutant OSE cells in these mice are the elevated expression of the tumor-suppressor Trp53 (p53) and its microRNA target, miR-34a-c. We propose that elevated TRP53 and miR-34a-c may exert negatively regulatory effects that reduce the proliferative potential of OSE cells leading to the low-grade serous adenocarcinoma phenotype.

A Voice-Operated Method for Administering the MMPI

Paper/pencil psychological tests such as the Minnesota Multiphasic Personality Inventory (MMPI) are difficult to complete independently by patients with limited hand function. This paper describes a voice recognition system developed to allow patients with no hand function to take the MMPI independently. Profiles generated by this system are not statistically different from those generated by standard MMPI booklet format. Limitations and possible extensions of the system as it currently exists are discussed.

Reliability and validity of the International Spinal Cord Injury Basic Pain Data Set items as self-report measures

Objective

To evaluate the psychometric properties of a subset of International Spinal Cord Injury Basic Pain Data Set (ISCIBPDS) items that could be used as self-report measures in surveys, longitudinal studies and clinical trials.

Setting

Community.

Methods

A subset of the ISCIBPDS items and measures of two validity criteria were administered in a postal survey to 184 individuals with spinal cord injury (SCI) and pain. The responses of the participants were evaluated to determine: (1) item response rates (as an estimate of ease of item completion); (2) internal consistency (as an estimate of the reliability of the multiple-item measures); and (3) concurrent validity.

Results

The results support the utility and validity of the ISCIBPDS items and scales that measure pain interference, intensity, site(s), frequency, duration, and timing (time of day of worst pain) in individuals with SCI and chronic pain. The results also provide psychometric information that can be used to select from among the ISCIBPDS items in settings that require even fewer items than are in the basic dataset.

Poor to modest agreement between rheumatoid arthritis response measures in clinical practice

OBJECTIVE

To evaluate the agreement among several rheumatoid arthritis (RA) response measures in a clinical setting.

METHODS

529 patients with RA were seen at 2 regular visits where the following response measures were determined: ACR-20, EULAR good or moderate (EULAR-GM), Simplified Disease Activity Index moderate (SDAI-M), Clinical DAI moderate (CDAI-M), and Patient Reported Outcomes Index-M 20 (PRO-IM-20). Each measure was modified to include a "worse" response, i.e. the inverse of the respective guidelines for a positive improvement response.Introduced for comparison was the Real-time Assessment of Disease Activity in Rheumatoid Arthritis (RADARA), a response measure that registers improvement if the patient's tender and swollen joint counts and HAQ score all improve and worsening if all three increase. Contingency tables comparing the three responses (worse, no change, and improvement) along with Cohen's kappa were calculated.

RESULTS

The mean (SD) baseline characteristics of the patients included: age 66.5 (10.7) years, RA duration 12.9 (11.0) years, 91.3% male, 84.1% rheumatoid factor positive, and a Disease Activity Score-28 of 3.5 (1.3). The percentage of patients who improved/worsened were as follows: ACR-20 4.7/9.1, EULAR-GM 23.4/26.3, SDAI-M 16.1/20.6, CDAI-M 16.3/20.0, PRO-IM-20 22.5/34.4, and RADARA 7.0/11.5. Agreement (kappa) was poor to slight (</= 0.4) between most of the response measures with the exception of RADARA/ACR-20 which showed substantial agreement (0.67) and SDAI/EULAR-GM and CDAI/EULAR-GM, which showed moderate agreement (0.54 and 0.52, respectively).

CONCLUSION

RA response measures can be made more informative by the addition of a "worse" response, although even in this case the agreement in the clinic setting is primarily poor to moderate.

Obesity intervention in persons with spinal cord injury

STUDY DESIGN

A single group uncontrolled trial.

OBJECTIVES

Despite widespread emphasis on the obesity-related health risks in persons with spinal cord injury (SCI), limited research has been carried out to intervene in this problem. This study was conducted to assess the initial effectiveness of a weight loss program on various health outcomes in persons with SCI.

SETTING

A rehabilitation center in Birmingham, Alabama, United States.

METHODS

A total of 16 individuals with chronic SCI who were overweight or obese participated in a weight management program that consisted of 12 weekly classes, covering nutrition, exercise, and behavior modification. Various outcomes were examined over a 6-month period (baseline, week 12, and week 24), including body composition measured by dual energy X-ray absorptiometry, physiologic measures, diet behavior, and psychosocial and physical functioning. Of these, 13 participants returned for the week 24 follow-up.

RESULTS

Weight loss averaged 3.5+/-3.1 kg (3.8% of the initial weight) at week 12 and 2.9+/-3.7 kg (3.0% of the initial weight) at week 24. There was a significant reduction from baseline values at weeks 12 and 24 in body mass index, anthropometric measurements, and fat mass and improvement in diet behavior and psychosocial and physical functioning, while lean mass and blood albumin and hemoglobin levels were maintained. A correlation analysis showed that a greater weight loss was importantly (r>0.4) associated with a greater reduction in total cholesterol at weeks 12 and 24 and in systolic and diastolic blood pressure at week 24. Several factors were important (r>0.4 or r<-0.4) in determining the success in weight loss, including age, race, marital and employment status, family history of overweight/obesity, level and duration of injury, and cholesterol level at baseline.

CONCLUSIONS

This is the first demonstration that a carefully planned program with time-calorie displacement diet is effective for overweight/obese individuals with SCI to lose weight without compromising total lean mass and overall health. It provides foundation for a future large clinical trial for weight loss of persons with SCI or other spinal cord dysfunction.

Regulation of transcripts encoding ADAMTS-1 (a disintegrin and metalloproteinase with thrombospondin-like motifs-1) and progesterone receptor by human chorionic gonadotropin in equine preovulatory follicles

One member of a new family of metalloproteinases, a disintegrin and metalloproteinase with thrombospondin-like motifs-1 (ADAMTS-1), has been found to be expressed and hormonally induced in granulosa cells of ovulating rodent follicles. Furthermore, the targeted disruption of the ADAMTS-1 gene resulted in ovarian defects associated with severely impaired fertility. While these data demonstrate the importance of ADAMTS-1 in rodent ovarian physiology, the potential role of ADAMTS-1 in the ovulatory process of monoovulatory species remains unknown. The objectives of this study were to clone the equine ADAMTS-1 primary transcript and to study its regulation during human chorionic gonadotropin (hCG)-induced ovulation. A 3573 bp follicular cDNA library clone was isolated and found to encode a nearly complete, highly conserved ADAMTS-1 homologue. Real-time RT-PCR analysis detected this transcript in diverse tIssues, including previously unreported sites of ADAMTS-1 expression such as the male reproductive tract, the follicular theca interna and the mature corpus luteum. The tIssue distribution of the progesterone receptor (PR), a known regulator of ADAMTS-1 expression in rodent preovulatory follicles, was found to overlap that of ADAMTS-1 in some tIssues. A study of the regulation of follicular ADAMTS-1 and PR mRNAs during the hCG-induced ovulatory process revealed distinct patterns of regulation in granulosa cells and in theca interna. In granulosa cells, ADAMTS-1 mRNA was found to be induced at 12 h post-hCG (P<0.05), followed by a return to basal levels by 30 h and a re-increase at 33-39 h (P<0.05). A concomitant increase in PR mRNA (P<0.05) was observed at 12 h post-hCG. In theca interna, abundant ADAMTS-1 mRNA was detected at all timepoints, and levels increased transiently at 33 h post-hCG (P<0.05), whereas no significant change was observed in PR mRNA. Together, these data demonstrate for the first time the hormonally regulated ovarian expression of ADAMTS-1 in a monoovulatory species, and identify a novel biphasic regulation of ADAMTS-1 in granulosa cells and a regulated expression in theca interna that were not previously observed in rodents.

Delivery of the oocyte from the follicle to the oviduct: a time of vulnerability

The multiplicity of genes regulated by the actions of LH in specific granulosa cell and cumulus cell microenvironments of the follicle during ovulation has now revealed how complex and finely tuned the ovulation process is. Although many proteases are expressed in the ovary and are hormonally regulated, the novel proteases ADAMTS-1 and cathepsin L, rather than the MMPs, have gained particular recognition. These may play critical roles in the eventual rupture of the follicle at the ovarian surface. Rupture is only one part of ovulation. Another important aspect is the actual release of the oocyte from the ovulation pore. Several recent studies have shown that the production of the matrix that is evidenced by cumulus expansion is somehow critical for extrusion to occur and for the oocyte to travel into the oviduct. At any point the oocyte may be trapped within a non-ovulating structure. Lastly, if the events of ovulation fail to occur before the events of luteinization are complete, oocytes are destined to degenerate within the non-ovulating structures.

Metallothionein-1 messenger RNA transcription in steroid-secreting cells of the rat ovary during the periovulatory period

An increase in metallothionein 1 (MT-1) mRNA was detected in the ovaries of immature Wistar rats that were primed with s.c. injection of 10 IU eCG followed 48 h later by 10 IU hCG s.c. to initiate the ovulatory process. Ovarian RNA was extracted at 0, 2, 4, 8, 12, 24, 72, 144, and 288 h after the primed animals were injected with hCG. These extracts were used for reverse transcription polymerase chain reaction (RT-PCR) differential display and Northern analyses that yielded complementary gene fragments for MT-1. Expression of MT-1 mRNA increased significantly by 24 h after hCG treatment and reached a peak at 144 h after hCG. In contrast, a disintegrin and metalloproteinase with thrombospondin motifs and a tissue inhibitor of metalloproteinase 1, which were also detected by the RT-PCR differential display procedure, reached a peak at 12 h after hCG and returned to control levels in the ovaries by 72 h after hCG. In situ hybridization indicated that most of the MT-1 mRNA was expressed in the vicinity of the theca interna of preovulatory follicles and in the lutein granulosa of postovulatory follicles. Thus, MT-1 mRNA expression is primarily in the vicinity of steroid-secreting areas of the ovary. The substantial increase in MT-1 mRNA expression might be important in protecting the ovarian tissues from oxidative stress generated by ovarian inflammatory events during the ovulatory process and luteinization.

Test-retest reliability of the Donovan spinal cord injury pain classification scheme

STUDY DESIGN

Videotape rating by independent viewers.

OBJECTIVE

To determine the test-retest reliability of the Donovan spinal cord injury (SCI) pain classification scheme.

SETTING

Rehabilitation Centre, Alabama, USA.

METHODS

A total of 28 individuals with SCI reported 60 pain sites. A structured interview and physical exam were used to illicit information to classify each pain site according to the Donovan criteria. All structured interviews and exams were videotaped. Three independent raters viewed the videotapes on two occasions, separated by a 3-month interval, and classified each pain site using the Donovan pain classification scheme.

RESULTS

Considering all three raters together, 78% of the pain sites were consistently classified from one period to the next. Within each rater, consistent classification ranged from 67 to 83%. However, inter-rater agreement for the classification of each pain site into the various types of pain was low for both periods (about 50-60%).

CONCLUSIONS

Pain classification within each rater generally showed adequate test-retest reliability when using the Donovan SCI pain classification scheme. However, reliability estimates of agreement across raters highlight the ongoing need to exam and improve the psychometric characteristics of the various pain classification schemes.

Gonadotropin-induced expression of pancreatitis-associated protein-III mRNA in the rat ovary at the time of ovulation

The ovulatory process in mammals involves gross physiological events in the ovary that cause transient deterioration of the ovarian connective tissue and rupture of the apical walls of mature follicles. This gonadotropin-induced process has features similar to an acute inflammatory reaction that affects most of the ovary. The present study reveals that the ovulatory events include induction of mRNA for pancreatitis-associated protein-III (PAP-III). Immature Wistar rats were primed with 10 IU equine chorionic gonadotropin s.c., and 48 h later the 12-h ovulatory process was initiated by 10 IU human chorionic gonadotropin (hCG) s.c. Ovarian RNA was extracted at 0, 2, 4, 8, 12 and 24 h after the animals were injected with hCG. The RNA extracts were used for RT-PCR differential display to detect PAP-III gene expression in the stimulated ovarian tissue. Northern blotting showed that transcription was significantly greater at 4-12 h after the ovaries had been stimulated by hCG. In situ hybridization indicated that PAP-III mRNA expression was limited mainly to the hilar region of the ovarian stroma, with most of the signal emanating from endothelial cells that lined the inner walls of blood vessels, and from small secondary follicles. Treatment of the animals with ovulation-blocking doses of indomethacin (an inhibitor of prostanoid synthesis) or epostane (an inhibitor of progesterone synthesis) revealed that ovarian transcription of PAP-III mRNA was moderately dependent on ovarian progesterone synthesis. In conclusion, the present evidence of an increase in PAP-III gene expression in gonadotropin-stimulated ovaries provides further evidence that the ovulatory process is comparable to an inflammatory reaction.

Pain classification following spinal cord injury: the utility of verbal descriptors

OBJECTIVES

To determine the predictive utility of verbal descriptors to distinguish between pain types following spinal cord injury (SCI).

DESIGN

Cross-sectional.

SETTING

USA.

METHODS

Participants (n=29) completed the Short Form - McGill Pain Questionnaire (SF-MPQ) for each pain site reported. A total of 64 pain sites were reported with 80% of the sample reporting multiple pain sites. Each pain site was categorized using three different SCI pain classification schemes. The predictive utility of verbal descriptors to distinguish between pain types was examined statistically using (1) each word separately, (2) a combination of words (ie, the SF-MPQ total subscales, the number of words chosen on each scale), and (3) discriminant function analysis.

RESULTS

There was a substantial overlap in the use of verbal descriptors across pain types. Few differences across pain types were found for endorsement of individual words, and differences across pain types were not found for any of the word combination scores. The majority of the verbal descriptors did not enter the step-wise discriminant functions for each SCI pain classification scheme, however, 'tingling' and 'aching' showed modest predictive utility for neuropathic and musculoskeletal pain, respectively. Correct classification was in the low range (ie, 39% to 82%, average=60%, with a 33% chance level). All three pain classification schemes showed the same general pattern of results.

CONCLUSION

In general, verbal descriptors alone offered marginal utility with regard to identifying specific pain types following SCI. Future directions alone and implications are discussed.

Impact of demographic and medical factors on satisfaction with life after spinal cord injury: a normative study

OBJECTIVE

The aim of this study was (1) to examine demographic and medical predictors of the Satisfaction With Life Scale (SWLS) among individuals with spinal cord injury (SCI) and (2) to provide a normative table for the SWLS that includes appropriate adjustments for the most important predictors of life satisfaction.

STUDY DESIGN

We examined predictors of the SWLS including age, education, sex, race, injury duration, number of rehospitalizations, marital status, employment status, SCI etiology, and level of neurological impairment.

PARTICIPANTS

Individuals in the National Spinal Cord Injury Statistical Center database [from 18 SCI model systems (1995-1999)] undergoing follow-up assessment were included for study.

OUTCOME MEASURE

Satisfaction With Life Scale.

RESULTS

Univariate analyses indicated that marital and employment status, race, sex, education, and injury duration were significant factors associated with scores on the SWLS. In general, individuals who were female, white, married, and currently employed and had a higher education and longer injury duration reported significantly higher scores on the SWLS (P < .01). Effect-size estimates for these factors ranged from 0.16 to 0.41. Regression analyses showed that education, employment status, and injury duration were the strongest unique predictors of satisfaction with life but accounted for only 10% of the variance.

CONCLUSION

The SWLS is a global measure of life satisfaction and is relatively unrelated to demographic and medical characteristics. Normative tables are provided for epidemiologic comparison.

Predictors of pain 1 year post-spinal cord injury

OBJECTIVE

To determine the predictive validity of demographic and medical characteristics to the subsequent development of pain 1 year post-spinal cord injury (SCI).

DESIGN

Prospective longitudinal design using data from 18 Model Spinal Cord Injury Systems of Care.

PARTICIPANTS

Adults 18 years or older with traumatic-onset SCI (n = 540) evaluated at 1 year postinjury.

OUTCOME MEASURES

A single item from the Short Form-12 that assessed pain interference in day-to-day activities using a 5-point Likert scale.

PREDICTOR VARIABLES

Demographic and medical characteristics, individual and total medical complications during rehabilitation, and insurance provider.

RESULTS

Univariate analyses showed age, education, marital status, primary occupation at the time of injury, American Spinal Injury Association motor score, and sponsor of care to be related to pain interference 1 year post-SCI. Polychotomous logistic regression indicated that age and occupational status at the time of injury were the only significant unique predictors of pain interference. The youngest (aged 18-29 years) and oldest (aged 60 years and older) age groups reported the least amount of pain interference, whereas individuals unemployed at the time of injury were significantly more likely to report pain interference. None of the other predictor variables was significant.

CONCLUSION

Age and occupational status appear to be important predictors of pain interference 1 year post-SCI. Future directions of study and limitations are discussed.

Bladder management and quality of life after spinal cord injury

OBJECTIVE

This study examines the quality of life among individuals with spinal cord injury requiring assistance for bowel and bladder management vs. those with independent control of bowel and bladder.

DESIGN

Two groups of 53 individuals each were matched case for case on age, education, sex, race, and lesion level. Outcome measures included the Satisfaction With Life Scale, the Craig Handicap Assessment and Reporting Technique (CHART), and the SF-12.

RESULTS

Satisfaction with life was significantly lower among dependent individuals with impaired bowel and bladder functioning as compared with individuals with independent bowel and bladder control. Similarly, dependent individuals reported greater self-reported handicap (CHART) than independent individuals in the areas of physical independence, mobility, and occupational functioning. However, dependent and independent individuals did not differ in the areas of social integration and economic self-sufficiency. Item analysis on the CHART item assessing number of social contacts initiated in the previous month suggested that dependent individuals may have difficulty initiating new social contacts. Independent individuals reported better overall physical health (SF-12) than dependent individuals. Mental health (SF-12), however, did not differ across groups.

CONCLUSIONS

Individuals with impaired bowel and bladder control reported lower quality of life on several domains compared with those with independent control of bowel and bladder. Though the two groups did not differ in self-reported social integration, dependent individuals may have greater difficulty creating new social relationships.

Quality of life after spinal cord injury caused by gunshot

OBJECTIVE

To determine what effect gunshot-caused spinal cord injury (SCI) has on self-reported quality of life (QOL) and on the frequency of pain sufficient to interfere with day-to-day activities.

DESIGN

Follow-up, case-control design.

SETTING

Analysis of data obtained from the (US) National Spinal Cord Injury Statistical Center from 18 funded Spinal Cord Injury Model Systems.

PARTICIPANTS

Individuals with traumatic onset SCI (n = 1901). From these, 111 persons with gunshot-caused SCI were matched to persons with nongunshot SCI.

MAIN OUTCOME MEASURES

Satisfaction with Life Scale (SWLS), the Craig Handicap Assessment and Reporting Technique (CHART), Medical Outcomes Study Short-Form Health Survey (SF-12), and an individual pain item from the SF-12.

RESULTS

No between-group differences were found on any of the QOL outcome measures. In contrast, those with SCI caused by gunshot reported that pain more frequently interfered with day-to-day activities than the matched comparison group.

CONCLUSIONS

SCI caused by gunshot appears largely unrelated to QOL, after controlling for demographic and medical characteristics associated with this group. Gunshot as a mechanism of SCI may place individuals at an increased risk of subsequent development of pain that interferes with activities of daily living.

3alpha-hydroxysteroid dehydrogenase messenger RNA transcription in the immature rat ovary in response to an ovulatory dose of gonadotropin

The ovulatory process in mammals involves a substantial increase in the metabolism of steroids and eicosanoids in response to a surge in LH or to an injection of hCG into experimental animals. This study provides evidence that the ovulatory stimulus causes induction of the gene for 3alpha-hydroxysteroid dehydrogenase (3alpha-HSD), an enzyme that belongs to several oxidoreductase superfamilies that affect steroid and eicosanoid metabolism. Immature Wistar rats were primed with 10 IU eCG s.c., and 48 h later the 12-h ovulatory process was initiated by 10 IU hCG s.c. Ovarian RNA was extracted at 0, 2, 4, 8, 12, and 24 h after injecting the animals with hCG. The RNA extracts were used for reverse transcription-polymerase chain reaction (PCR) differential display to detect gene expression in the stimulated ovarian tissue. One of the PCR primer sets differentially amplified a cDNA fragment that is 52.3% homologous with a 3alpha-HSD gene in rat liver. Northern analyses revealed that maximum transcription was at 8 h after the animals had been treated with hCG. The Northerns also indicated that the 3alpha-HSD cDNA probe cross-hybridized with as many as six different bands of mRNA on the blots. In situ hybridization localized 3alpha-HSD mRNA in the granulosa and thecal layers of mature follicles and in newly formed corpora lutea at 24 h after the ovulatory stimulus. In conclusion, gene(s) for 3alpha-HSD are transcribed in ovarian follicles in response to an ovulatory dose of gonadotropin. A possible function of the oxidoreductase enzyme that is translated from the 3alpha-HSD mRNA may be to reduce the toxic aldehyde and ketone components of the steroids and eicosanoids that accumulate in the mammalian ovary at the time of ovulation.

Nursing home residence: quality of life among individuals with spinal cord injury

OBJECTIVE

To examine the quality of life among individuals with spinal cord injury currently living in a nursing home vs. community residence.

DESIGN

A case-control design matched nursing home and community residents on numerous demographic and medical characteristics. Two groups of 37 individuals (nursing home vs. community residents) were matched case-for-case on age (i.e., within 10 yr), education, gender, race, marital status, and impairment level. Etiology of spinal cord injury, American Spinal Injury Association Impairment Index at the time of rehabilitation discharge, and injury duration, although not specifically matched, were not significantly different between groups (P > 0.05). Outcome measures included the Satisfaction With Life Scale, and the Craig Handicap Assessment and Reporting Technique (CHART).

RESULTS

Results indicated that overall self-reported quality of life was significantly lower among nursing home residents compared with matched community-dwelling residents (mean = 18 and 14, respectively). Similarly, self-reported handicap was significantly higher among the nursing home residents compared with community residents (mean = 337 and 181, respectively), particularly in the areas of physical independence, mobility, occupational functioning, and economic self-sufficiency (P < 0.05). In contrast, the score on the CHART social integration subscale was similar across groups (P > 0.05).

CONCLUSION

Despite matching numerous variables, the nursing home residents demonstrated significantly lower quality of life across multiple domains as compared with their community-dwelling counterparts. Additional research is needed to examine the specific mechanisms associated with these differences.

Gunshot versus nongunshot spinal cord injury: acute care and rehabilitation outcomes

OBJECTIVE

To examine the impact of gunshot-caused spinal cord injury on acute and rehabilitative care outcome using a case control design.

DESIGN

Two groups (i.e., gunshot- vs. nongunshot-caused spinal cord injury) of 212 individuals were matched case-for-case on age (i.e., within 10 yr), education, gender, race, marital status, primary occupation, impairment level, and Model System region. Outcome measures included length of hospital stay, functional status (FIM), treatment charges, and home discharge rates.

RESULTS

The two groups did not differ in the length of stay during acute and rehabilitative care, charges during rehabilitative care, or postrehabilitation discharge placement. Several significant between-group differences in treatment procedures were noted (e.g., prevalence of spinal surgery), which may, in part, account for the higher acute-care charges among those persons with nongunshot-caused spinal cord injury.

CONCLUSION

Once an individual is stabilized and admitted for rehabilitative care, gunshot etiology of spinal cord injury seems largely unrelated to the initial rehabilitation outcome.

New signaling pathways for hormones and cyclic adenosine 3',5'-monophosphate action in endocrine cells

The glycoprotein hormones, ACTH, TSH, FSH, and LH regulate diverse functions in endocrine cells. Although cAMP and PKA have long been shown to mediate specific intracellular signaling events including the transcription of specific genes via the CREB-CBP complex, recent observations have indicated that PKA does not account for all of the intracellular targets of cAMP. For example, TSH stimulation of thyroid cell proliferation is not completely blocked by PKA inhibitors. TSH and FSH can stimulate PKB phosphorylation by a PKAindependent but PI3-K/PDK1-dependent pathway. An FSH inducible kinase, Sgk, has recently been shown to be a close relative of PKB. Sgk is also a target of PI3-K-PDK1 pathway, indicating that some effects previously ascribed to PKB may be mediated by this inducible kinase. The identification of novel cAMP-binding proteins that exhibit guanine nucleotide exchange (GEF) activity (cAMP-GEFS; Epacs) has open new doors for cAMP action that include activation of small GTPases such as Rap1a, Rap2, and possibly Ras. These GTPases are known activators of downstream kinase cascades, including p38MAPK and Erk1/2 as well as PI3-K. Thus, FSH and TSH activation of PKB and Sgk may occur via this alternative cAMP pathway that involves cAMP-GEFs and the activation of the PI3-K/PDK1 pathway.

Graafian follicle function and luteinization in nonprimates

The ovarian follicle has two major functions. It provides for the maturation and release of a fertilizable oocyte. It also forms the corpus luteum, which promotes and maintains implantation of the embryo. For these processes to occur, the follicle has to grow, ovulate, and luteinize. The transition of granulosa cells to luteal cells requires rapid changes in the expression of specific genes. In this transition, many genes expressed in granulosa cells are turned off, whereas the genes controlling terminal differentiation to luteal cells are induced. Of major importance are changes in the regulation of specific kinase cascades that regulate proliferation and differentiation as well as specific protease cascades that control the remodeling of the follicle during ovulation and formation of the corpus luteum. The dramatic reprogramming of gene expression in granulosa cells leading to that of luteal cells is complete within 5 to 7 hours and is irreversible.

Female fertility is reduced in mice lacking Ca2+/calmodulin-dependent protein kinase IV

Ca2+/calmodulin-dependent protein kinase IV (CaMKIV) is a serine/threonine protein kinase with limited tissue distribution. CaMKIV is highly expressed in the testis, where it is found in transcriptionally inactive elongating spermatids. We have recently generated mice deficient in CaMKIV. In the absence of CaMKIV, the exchange of sperm nuclear basic proteins in male spermatids is impaired, resulting in male infertility secondary to defective spermiogenesis. The involvement of CaMKIV in female fertility has not been addressed. Here we report that female fertility is markedly reduced in CaMKIV-deficient mice due to impaired follicular development and ovulation. CaMKIV is expressed in the ovary, where it is localized in granulosa cells. We further find that in cultured granulosa cells, CaMKIV expression and subcellular localization are hormonally regulated. As granulosa cells differentiate, CaMKIV levels decrease and the kinase translocates from the nucleus into the cytoplasm. Our results demonstrate a critical role for CaMKIV in female reproduction and point to a potential function in granulosa cell differentiation.

Expression of tumor necrosis factor-stimulated gene-6 in the rat ovary in response to an ovulatory dose of gonadotropin

Current evidence supports the hypothesis that the biochemical events of mammalian ovulation are analogous to an acute inflammatory reaction. This study reveals that tumor necrosis factor-stimulated gene-6 (TSG-6), which encodes a member of the superfamily of hyaluronan-binding proteins that is specifically translated in inflammatory reactions, is expressed in ovarian follicles that have been induced to ovulate. Immature Wistar rats were primed with 10 IU equine CG s.c.; and 48 h later, the 12-h ovulatory process was initiated by 10 IU human CG (hCG), s.c.. Ovarian RNA was extracted at 0, 2, 4, 8, 12, and 24 h after the primed animals were injected with hCG. The RNA extracts were used for RT-PCR differential display of amplified complementary DNAs (cDNAs) that represented gene expression in the stimulated ovarian tissue. Northern analysis of one of the differentially amplified cDNAs confirmed that it was part of a gene that was substantially up-regulated at 4-8 h after the ovaries had been stimulated by hCG. Subcloning and sequence analysis revealed that the cDNA matched the gene for TSG-6. In situ hybridization indicated that the TSG-6 messenger RNA was primarily located in the cumulus mass and the antral granulosa cells of large ovarian follicles. In conclusion, the data show that expression of TSG-6 is an integral part of the cascade of inflammatory-like changes that occur in an ovulatory follicle in response to a trophic hormone that couples with luteinizing hormone/hCG receptors.

Expression of regulator of G-protein signaling protein-2 gene in the rat ovary at the time of ovulation

The ovulatory process in mammals begins when an endogenous surge in LH circulates to the ovary and couples with receptors in the plasma membranes of granulosa cells in mature ovarian follicles. This study provides evidence that the ovulatory stimulus includes induction of the gene for regulator of G-protein signaling protein-2 (RGS2). Immature Wistar rats were primed with 10 IU eCG s.c., and 48 h later the 12-h ovulatory process was initiated by 10 IU hCG (a homolog of LH) s.c. Ovarian RNA was extracted at 0, 2, 4, 8, 12, and 24 h after injecting the animals with hCG. The RNA extracts were used for reverse transcription-polymerase chain reaction differential display to detect gene expression in the stimulated ovarian tissue. Two of the amplified cDNAs that were upregulated within 2 h after the ovaries had been stimulated by hCG were homologous to segments of the mouse gene for RGS2. In situ hybridization indicated that the RGS2 mRNA was expressed in the granulosa layer of mature follicles. In conclusion, the gene for RGS2, which is known to regulate membrane signaling pathways, is transcribed in ovarian follicles in response to an ovulatory dose of gonadotropin.

Regulation of AP1 (Jun/Fos) factor expression and activation in ovarian granulosa cells. Relation of JunD and Fra2 to terminal differentiation

AP1 transcription factors control rapid responses of mammalian cells to stimuli that impact proliferation, differentiation, and transformation. To determine which AP1 factors are present in and regulated by hormones in ovarian cells during specific stages of proliferation and differentiation, we used both in vitro and in vivo models, Western blotting, immunohistochemistry, DNA binding assays, and transfections of AP1 promoter-reporter constructs. The expression patterns of Jun and Fos family members in response to hormones (follicle-stimulating hormone (FSH), luteinizing hormone (LH), and cAMP) were distinct. JunB, c-Jun, c-Fos, and Fra2 were rapidly but transiently induced by FSH in immature granulosa cells. JunD and Fra2 were induced by LH and maintained as granulosa cells terminally differentiated into luteal cells. Forskolin and phorbol myristate acetate acted synergistically to enhance transcription of an AP1(-73COL)-luciferase construct. JunD appears to be one mediator of this effect, since JunD was a major component of the AP1-DNA binding complex in granulosa cells, and menin, a selective inhibitor of JunD, blocked transcription of -73COL-luciferase. Thus, FSH and LH via cAMP induce specific AP1 factors, the AP1 expression patterns are distinct, and that of JunD and Fra2 correlates with the transition of proliferating granulosa cells to terminally differentiated, non-dividing luteal cells.

Ovulation: a multi-gene, multi-step process

The luteinizing hormone (LH) surge initiates a cascade of proteolytic events that control ovulation. One of the genes induced by LH is the progesterone receptor (PR). Because mice with a mutant PR gene (PRKO) fail to ovulate and are infertile, we have used them as a model in which to determine PR target genes that might mediate the ovulatory process. The matrix metalloproteinases (MMPs: MMP2, MMP9, and MMP13) appear to be expressed in ovaries of PRKO mice in a manner similar to that in their wild-type littermates. However, the expression of two other types of proteases, cathepsin L (a member of the papain family) and ADAMTS-1 (A Disintegrin And Metalloproteinase with Thrombospondin-like motifs), are selectively induced in granulosa cells of preovulatory follicles by the LH surge. Maximal levels of these proteases are observed at 12-16 h after an LH surge, the time of ovulation. Furthermore, mRNAs encoding cathepsin L and ADAMTS-1 are reduced in the PRKO mice compared to their wild-type littermates. These novel observations indicate that these two proteases regulate some key step(s) controlling ovulation.

Follicle-Stimulating hormone (FSH) stimulates phosphorylation and activation of protein kinase B (PKB/Akt) and serum and glucocorticoid-lnduced kinase (Sgk): evidence for A kinase-independent signaling by FSH in granulosa cells

FSH stimulates in ovarian granulosa cells diverse, differentiation-dependent responses that implicate activation of specific cellular signaling cascades. In these studies three kinases were investigated to determine their relationship to FSH, cAMP, and A kinase signaling: protein kinase B (PKB/Akt), serum and glucocorticoid-induced kinase (Sgk), and p38 mitogen-activated protein kinase (p38MAPK). The phosphorylation (activation) of these kinases was analyzed by using selective agonists/inhibitors: forskolin/H89 for cAMP-dependent protein kinase (A kinase), insulin-like growth factor I (IGF-I)/LY294002 and wortmannin for phosphatidylinositol-dependent kinase (PI3-K), and phorbol myristate (PMA)/GF109203X for diacylglycerol and Ca++-dependent kinases (C kinases). An inhibitor (PD98059) of MEK1, which regulates extracellular regulated kinases (ERKs), and SB203580, which inhibits p38MAPK, were also used. In addition, we analyzed the expression of the recently described, cAMP-regulated guanine nucleotide exchange factors (cAMP-GEFI and GEFII) that impact Ras-related GTPases and Raf kinases, known regulators of various protein kinase cascades. We provide evidence that FSH, forskolin, and 8-bromo-cAMP stimulate phosphorylation of PKB by mechanisms involving PI3-K (LY294002/wortmannin sensitive) not A kinase (H89 insensitive), a pattern of response mimicking that of IGF-I. In contrast, FSH induction and phosphorylation of Sgk protein requires A kinase (H89 sensitive) but also involves PI3-K (LY294002 sensitive) as well as p38MAPK (SB203580 sensitive) pathways. PMA (C kinase) abolished FSH-mediated (but not IGF-I-mediated) phosphorylation of PKB at a step(s) upstream of PI3-K and independent of A kinase. Lastly, FSH-mediated phosphorylation of p38MAPK is negatively affected by A kinase and PI3-K, suggesting that it may be downstream of specific members of the cAMP-GEF/Rap/Raf pathway. We propose that cAMP activation of A kinase is obligatory for transcription of Sgk in granulosa cells whereas cAMP (IGF-I-like)-mediated phosphorylation (activation) of PKB and Sgk (via PI3-K), as well as p38MAPK, involves other cellular events. These results provide new and exciting evidence that cAMP acts in granulosa cells by A kinase-dependent and -independent mechanisms, each of which controls specific kinase cascades.

Induction of early growth response protein-1 gene expression in the rat ovary in response to an ovulatory dose of human chorionic gonadotropin

Granulosa cells in a mature ovarian follicle have an abundance of LH/hCG receptors that respond rapidly to an ovulatory surge in gonadotropins. Within minutes, membrane signal transduction sets in motion metabolic changes that lead to follicular rupture. This study provides evidence that the initial ovarian response to such an ovulatory stimulus includes induction of the immediate-early transcription factor gene for early growth response protein-1 (Egr-1). Immature Wistar rats were primed with 10 IU equine CG (eCG), sc, and 48 h later the 12-h ovulatory process was initiated by 10 IU hCG, sc. Ovarian RNA was extracted at 0, 0.5, 1, 2, 4, 8, 12, and 24 h after the primed animals were injected with hCG. The RNA extracts were used for RT-PCR differential display for random detection of gene expression in the stimulated ovarian tissue. Northern analysis of one of the differentially amplified complementary DNAs confirmed that it was part of a gene that was significantly up-regulated within 1 h after the ovaries had been stimulated by hCG. Maximum transcription was at 4 h after hCG, and expression declined to 0 h control levels by 24 h after hCG. Subcloning and sequence analysis revealed that the complementary DNA matched the gene for Egr-1. In situ hybridization indicated that the Egr-1 messenger RNA was in the granulosa layer of mature follicles. Western blotting confirmed the temporal pattern of Egr-1 expression detected by differential display, Northern analysis and in situ hybridization. The Egr-1 protein is approximately 84 kDa. In conclusion, the data show that expression of the zinc finger transcription factor Egr-1 is an early event in the cascade of inflammatory-like changes that occur in an ovulatory follicle in response to a trophic hormone.

Progesterone-regulated genes in the ovulation process: ADAMTS-1 and cathepsin L proteases

Ovulation is a precisely timed process by which a mature oocyte is released from an ovarian follicle. This process is initiated by the pituitary surge of luteinizing hormone (LH), is temporally associated with transcriptional regulation of numerous genes, and is presumed to involve the synthesis and/or activation of specific proteases that degrade the follicle wall. The progesterone receptor (PR), a nuclear receptor transcription factor, is induced in granulosa cells of preovulatory follicles in response to the LH surge and has been shown to be essential for ovulation, because mice lacking PR fail to ovulate and are infertile. Using these mice as a model in which to elucidate PR-regulated genes in the ovulation process, we show that the matrix metalloproteinases MMP-2 and MMP-9 are not targets of PR during ovulation. In contrast, two other proteases, ADAMTS-1 (A disintegrin and metalloproteinase with thrombospondin-like motifs) and cathepsin L (a lysosomal cysteine protease), are transcriptional targets of PR action. ADAMTS-1 is induced after LH stimulation in granulosa cells of preovulatory follicles and depends on PR. Cathepsin L is induced in granulosa cells of growing follicles by follicle-stimulating hormone, but the highest levels of cathepsin L mRNA occur in preovulatory follicles in response to LH in a PR-dependent manner. The identification of two regulated proteases in the ovary, together with their abnormal expression in anovulatory PR knockout mice, suggests that each plays a critical role in follicular rupture and represents a major advance in our understanding of the proteolytic events that control ovulation.

Ovarian expression of a disintegrin and metalloproteinase with thrombospondin motifs during ovulation in the gonadotropin-primed immature rat

Mammalian ovulation is a dynamic process that requires degradation of the collagenous connective tissue in the thecal layers of a mature follicle. In this reverse transcription-polymerase chain reaction differential display study, gonadotropin-primed immature rats were used to detect ovarian expression of a relatively new type of disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS-1) that is known to cleave extracellular matrix in acutely inflamed tissues. Immature Wistar rats were primed with 10 IU eCG s. c., and the temporal pattern of expression of the ADAMTS-1 gene was delineated by extracting ovarian RNA at 0, 2, 4, 8, 12, and 24 h after induction of ovulation by injecting the primed animals with 10 IU hCG s.c. The differential display data, Northern analyses, and in situ hybridization micrographs all showed significant up-regulation of ADAMTS-1 gene expression by 8 h after hCG administration. The in situ data indicated that the ADAMTS-1 mRNA was in the granulosa layer of mature follicles. Expression reached a peak at 12 h and remained elevated at 24 h after hCG. ADAMTS-1 gene expression was impaired by the antiprogesterone agent epostane, but this inhibition could be overcome by exogenous progesterone. ADAMTS-1 expression was not affected when ovulation was blocked by treatment of the animals with the anti-eicosanoid agent indomethacin. In conclusion, the temporal pattern of expression of this gene, and its apparent regulation by progesterone, suggests that ADAMTS-1 has a significant role in the inflammatory events of the ovulatory process.

Characterization of ovarian carbonyl reductase gene expression during ovulation in the gonadotropin-primed immature Rat

In this differential-display polymerase chain reaction-based study, four different primer sets generated cDNA fragments of ovarian carbonyl reductase genes that were uniquely expressed during the ovulatory process in eCG-primed immature rats. The temporal pattern of expression of this aldo-keto reductase gene was delineated by extracting ovarian RNA at 0, 2, 4, 8, 12, and 24 h after induction of ovulation via injection of the primed animals with hCG. The results showed that at least four homologous forms of this gene were transcribed during ovulation. Northern blot analyses indicated a 14-fold increase in ovarian mRNA for carbonyl reductase, with expression reaching a peak at 8 h after hCG treatment and then declining to negligible levels during the next 16 h. In situ hybridization revealed that most of the transcription was in the thecal connective tissue of the ovary and was absent from the granulosa layer of ovarian follicles. Treatment of the animals with ovulation-blocking doses of epostane (an inhibitor of progesterone synthesis) or indomethacin (an inhibitor of prostanoid synthesis) did not reduce the expression of ovarian carbonyl reductase. Nevertheless, the temporal pattern of expression of carbonyl reductase after the induction of ovulation suggests that this enzyme activity is at least indirectly associated with the ovulatory process.