Romantic Love and Reproductive Hormones in Women

Role of hormones in bone remodeling in the craniofacial complex: A review

Background

Diseases such as periodontitis and osteoporosis are expected to rise tremendously by 2050. Bone formation and remodeling are complex processes that are disturbed in a variety of diseases influenced by various hormones.

Objective

This study aimed to review and present the roles of various hormones that regulate bone remodeling of the craniofacial complex.

Methods

A literature search was conducted on PubMed and Google Scholar for studies related to hormones and jawbone. Search strategies included the combinations ("name of hormone" + "dental term") of the following terms: "hormones", "oxytocin", "estrogen", "adiponectin", "parathyroid hormone", "testosterone", "insulin", "angiotensin", "cortisol", and "erythropoietin", combined with a dental term "jaw bone", "alveolar bone", "dental implant", "jaw + bone regeneration, healing or repair", "dentistry", "periodontitis", "dry socket", "osteoporosis" or "alveolitis". The papers were screened according to the inclusion criteria from January 1, 2000 to March 31, 2021 in English. Publications included reviews, book chapters, and original research papers; in vitro studies, in vivo animal, or human studies, including clinical studies, and meta-analyses.

Results

Bone formation and remodeling is a complex continuous process involving many hormones. Bone volume reduction following tooth extractions and bone diseases, such as periodontitis and osteoporosis, cause serious problems and require a great understanding of the process.

Conclusion

Hormones are with us all the time, shape our development and regulate homeostasis. Newly discovered effects of hormones influencing bone healing open the possibilities of using hormones as therapeutics to combat bone-related diseases.

Toward consistent reporting of sample characteristics in studies investigating the biological mechanisms of romantic love

In this non-systematic review, we consider the sample reporting practices of 42 studies up to and including 2021 investigating the biological mechanisms of romantic love (i.e., 31 neuroimaging studies, nine endocrinological studies, one genetics study, and one combined neuroimaging and genetics study). We searched scientific databases using key terms and drew on our and other authors' knowledge to identify studies that investigated the mechanisms associated with romantic love using neuroimaging, endocrinological, and genetic methods. Only studies with a group or entire sample experiencing romantic love were included. The aim was to collate all relevant studies and determine the comparability of studies and ability to assess the generalizability of findings. We summarize how these studies report sex/gender, age, romantic love, relationship duration/time in love, and sample descriptors. We then outline the case for promoting comparability and the ability to determine generalizability in future studies. The findings indicate a limited ability to compare studies' samples or make an assessment of the generalizability of findings. Existing studies are not representative of the general population in a particular country or globally. We conclude by presenting ideas about how best to report sex, age, romantic love characteristics, relationship status, time in love, relationship duration, relationship satisfaction, type of unrequited love, sexual activity, cultural characteristics, socio-economic status, student status, and method-relevant descriptors. If our ideas are adopted, in part or in whole, we expect the comparability of studies to increase. Adopting our ideas will also make it easier to make an assessment of the generalizability of findings.

Recognition of Gonadal Development in Eriocheir sinensis Based on the Impulse of Love at First Sight

Given the difficulty in identifying individuals with different degrees of ovarian development, we developed a new device utilizing the hypothesis of mutual attraction behavior between male and female crabs with mature gonads by releasing the sexual pheromone so they could be examined. From a total of 40 female crabs, 10 were isolated within half an hour. Histological analysis showed that the ovaries of crabs in the isolated group were in stage IV, while those of the control groups were in stage III. In addition, progesterone (PROG) in experimental groups was significantly reduced compared with the control group (p < 0.05), but no significant difference was detected in estradiol (E2). In response to the different developmental stages, hemolymph biochemical indices and the determination of gonadal fatty acids profiles were explored. The results indicated only C18:4 showed a significant difference between these two groups. A transcriptome was generated to determine the genes involved in the mutual attraction process; differentially expressed genes (DEGs) were significantly related to gonadal development. Therefore, the device can be used to isolate Chinese mitten crabs with stage IV ovarian development.

Brain and Pituitary Transcriptome Analyses Reveal the Differential Regulation of Reproduction-Related LncRNAs and mRNAs in Cynoglossus semilaevis

Long noncoding RNAs (lncRNAs) have been identified to be involved in half-smooth tongue sole (Cynoglossus semilaevis) reproduction. However, studies of their roles in reproduction have focused mainly on the ovary, and their expression patterns and potential roles in the brain and pituitary are unclear. Thus, to explore the mRNAs and lncRNAs that are closely associated with reproduction in the brain and pituitary, we collected tongue sole brain and pituitary tissues at three stages for RNA sequencing (RNA-seq), the 5,135 and 5,630 differentially expressed (DE) mRNAs and 378 and 532 DE lncRNAs were identified in the brain and pituitary, respectively. The RNA-seq results were verified by RT-qPCR. Moreover, enrichment analyses were performed to analyze the functions of DE mRNAs and lncRNAs. Interestingly, their involvement in pathways related to metabolism, signal transduction and endocrine signaling was revealed. LncRNA-target gene interaction networks were constructed based on antisense, cis and trans regulatory mechanisms. Moreover, we constructed competing endogenous RNA (ceRNA) networks. In summary, this study provides mRNA and lncRNA expression profiles in the brain and pituitary to understand the molecular mechanisms regulating tongue sole reproduction.

Romantic Love and Sleep Variations: Potential Proximate Mechanisms and Evolutionary Functions

This article provides a narrative review of what is known about romantic love and sleep variations and provides possible explanations for the association. Romantic love and sleep are described using a comprehensive, unifying framework advocated by Tinbergen. We summarise the findings of studies investigating the relationship between romantic love and sleep. Sleep variations are associated with romantic love in adolescents and young adults. We then detail some proximate mechanisms that may contribute to sleep variations in people experiencing romantic love before considering potential evolutionary functions of sleep variations in people experiencing romantic love. The relationship between symptoms of psychopathology and sleep variations in people experiencing romantic love is described. With the current state of knowledge, it is not possible to determine whether sleep variations associated with romantic love are adaptations or by-products of romantic love. We conclude by proposing areas for future research.

CortiLove: A pilot study on hair steroids in the context of being in love and separation

While romantic infatuation and separation influence psychological and physiological functioning, the hypothalamic-pituitary-adrenal axis with its biomarkers cortisol, dehydroepiandrosterone (DHEA), and progesterone central for coping and distress has been scarcely researched in this context. In particular, endocrine hair analyses assumed to be more valid than saliva or blood assessments for studying long-term processes have not yet been conducted in the context of romantic love. Thus, 101 female subjects in phases of infatuation (n = 16), separation (n = 14), long-term relationships (n = 40), and singlehood (n = 31) reported psychological distress and provided 1 cm hair samples for the assessment of long-term integrated cortisol, DHEA, and progesterone over the last month. Separated, infatuated, and single women exhibited higher cortisol levels than those in a long-term relationship (all ps ≤ .031), while self-reported distress was only evident in separated individuals. Further, no group differences for progesterone (p = .602), but higher DHEA levels in the separation (p = .009) and single group (p = .016) compared to the long-term relationship group were detected. This is the first study showing that compared to women in long-term relationships, infatuation, separation, and single groups exhibit higher levels of physiological, but not necessarily self-reported indicators of distress. These findings, albeit on a very small and preliminary sample, are discussed in the context of the stress-buffering effect of relationships, and provide important starting points for bigger, more balanced studies combining multimodal self-report and biological markers in psychological research of romantic love.

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Higher hair cortisol in separation, infatuation, singlehood vs. stable relationship.

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Higher hair DHEA only in separation and singlehood vs. stable relationship.

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No group difference for progesterone.

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Divergence of physiological and self-reported indicators of distress.

Proximate and Ultimate Perspectives on Romantic Love

Romantic love is a phenomenon of immense interest to the general public as well as to scholars in several disciplines. It is known to be present in almost all human societies and has been studied from a number of perspectives. In this integrative review, we bring together what is known about romantic love using Tinbergen’s “four questions” framework originating from evolutionary biology. Under the first question, related to mechanisms, we show that it is caused by social, psychological mate choice, genetic, neural, and endocrine mechanisms. The mechanisms regulating psychopathology, cognitive biases, and animal models provide further insights into the mechanisms that regulate romantic love. Under the second question, related to development, we show that romantic love exists across the human lifespan in both sexes. We summarize what is known about its development and the internal and external factors that influence it. We consider cross-cultural perspectives and raise the issue of evolutionary mismatch. Under the third question, related to function, we discuss the fitness-relevant benefits and costs of romantic love with reference to mate choice, courtship, sex, and pair-bonding. We outline three possible selective pressures and contend that romantic love is a suite of adaptions and by-products. Under the fourth question, related to phylogeny, we summarize theories of romantic love’s evolutionary history and show that romantic love probably evolved in concert with pair-bonds in our recent ancestors. We describe the mammalian antecedents to romantic love and the contribution of genes and culture to the expression of modern romantic love. We advance four potential scenarios for the evolution of romantic love. We conclude by summarizing what Tinbergen’s four questions tell us, highlighting outstanding questions as avenues of potential future research, and suggesting a novel ethologically informed working definition to accommodate the multi-faceted understanding of romantic love advanced in this review.

Differences in and Correlates of Sexual Function in Infertile Women with and without Polycystic Ovary Syndrome

Background

The aim of this study was to examine sexual function and its correlates among infertile women with polycystic ovary syndrome (PCOS) in comparison with their non-PCOS counterparts.

Materials and Methods

In this case-control study, 209 infertile women (116 PCOS and 93 non-PCOS) from Tehran, Iran, were evaluated in February and March 2018. Female sexual function index (FSFI), hormonal status, and docu- mented reports of hyperandrogenic manifestations of the patients were investigated.

Results

The mean age of the patients was 32.00 ± 5.00 years old. Eighty-four (40.2%) patients including 42.2% of the PCOS patients and 37.6% of the non-PCOS cases (P>0.05), were suspected of female sexual dysfunction (FSD). The most impaired functions in both groups were desire and arousal. Sexual function was not significantly different between the groups. However, PCOS women had more orgasm problems and acne worsened their sexual function. To- tal FSFI was positively associated with prolactin level but negatively associated with central obesity in the non-PCOS group; it was negatively correlated with marital duration in the PCOS group. Luteinizing hormone (LH) and pain, pro- lactin level and lubrication, and central obesity and arousal were correlated in the non-PCOS women. Prolactin level and orgasm, marital duration and arousal, and marital duration and the total FSFI were correlated in the PCOS women.

Conclusion

Sexual function was similarly low in infertile PCOS and non-PCOS women. However, orgasm problems and the negative effect of acne varied between the two groups. Further investigations may target how hormonal profile may affect sexual function. Practitioners should scrutinize the specific impaired sexual domains and their correlated conditions in PCOS women, notably orgasm, acne, and prolactin level. Interventions should be well tailored based on particular needs of infertile PCOS women.

Universality of the Triangular Theory of Love: Adaptation and Psychometric Properties of the Triangular Love Scale in 25 Countries

The Triangular Theory of Love (measured with Sternberg's Triangular Love Scale - STLS) is a prominent theoretical concept in empirical research on love. To expand the culturally homogeneous body of previous psychometric research regarding the STLS, we conducted a large-scale cross-cultural study with the use of this scale. In total, we examined more than 11,000 respondents, but as a result of applied exclusion criteria, the final analyses were based on a sample of 7332 participants from 25 countries (from all inhabited continents). We tested configural invariance, metric invariance, and scalar invariance, all of which confirmed the cultural universality of the theoretical construct of love analyzed in our study. We also observed that levels of love components differ depending on relationship duration, following the dynamics suggested in the Triangular Theory of Love. Supplementary files with all our data, including results on love intensity across different countries along with STLS versions adapted in a few dozen languages, will further enable more extensive research on the Triangular Theory of Love.