Understanding desiccation tolerance and sex-specific responses in Bryum argenteum: insights from phenological phases and physiological analyses

BACKGROUND AND AIMS

Desiccation tolerance (DT) is crucial for survival in arid environments, where organisms develop strategies in reproduction, maintenance, and defense to cope with water scarcity. Therefore, investigating the relationship between reproduction and DT is essential to understand the ecology and adaptive strategies of species. This study explores the connection between the development of male and female gametangia in the moss Bryum argenteum and the decrease in DT during the progression of phenological phases in gametangia and protonema.

METHODS

Samples collected from a dry tropical forest in Brazil were cultivated, cloned, and subjected to desiccation. Subsequently, the physiological parameters of shoots and protonemata were analysed. Shoot and protonema regeneration were monitored for 28 days after the physiological analyses. Both phases were subjected to control and desiccation treatments.

KEY RESULTS

Significant effects of desiccation and sex on the physiological parameters and regeneration capacity of shoots and protonemata were found. Male shoots generally exhibited lower values in Fv/Fm, and ϕPSII, while females demonstrated higher values and better recovery after desiccation. Protonemata also showed variation in Fv/Fm over time and sex, with no significant differences in ϕPSII between them. Desiccated male shoots had higher mortality rates and produced fewer new shoots. Regarding the females, the regeneration patterns varied between the desiccation-exposed groups and the control, with decreased shoot production, and some protonemata growing into filaments without forming shoots.

CONCLUSION

These findings improve our understanding of bryophytes ecological responses to desiccation stress and provide insights into their adaptive strategies in challenging environments, such as the possible rarity of males in dioicous mosses populations.

Sex and oestrous cycle are not mediators of S-ketamine's rapid-antidepressant behavioural effects in a genetic rat model of depression

BACKGROUND

Recent preclinical and clinical studies have shed light on the possible impact of sex and oestrous/menstrual cycle on ketamine's antidepressant action but with incongruous results. The preclinical studies that have shown the effects of ovarian sex hormones have not done so in animal models of depression. Thus, the aim of the present study is to scrutinize the acute behavioural responses to a subanaesthetic dose of S-ketamine in males vs females and in different oestrous phases in free-cycling females in a well-powered translational approach.

METHODS

We evaluated the behavioural sensitivity to 20 mg/kg S-ketamine (i.p.) in male and female Flinders sensitive line (FSL) rats and their counterpart Flinders resistant line (FRL) rats subjected to the open field and forced swim tests. Female rats were disaggregated into different oestrous phases, and the behavioural outcomes were compared.

RESULTS

Acute administration of S-ketamine had robust antidepressant-like effects in FSL rats. Within our study power, we could not detect sex- or oestrous-cycle-specific different antidepressant-like responses to S-ketamine in FSLs. Fluctuations in the levels of ovarian sex hormones across different oestrous cycles did not behaviourally affect the S-ketamine's rapid-acting antidepressant mode of action. No sex- or oestrous-cycle-related impact on behavioural despair was observed even among FRLs and saline-treated FSLs.

CONCLUSIONS

We conclude that physiological oscillations of estrogen and progesterone levels neither amplify nor diminish the behavioural antidepressant-like effect of S-ketamine. In addition, fluctuations of ovarian sex hormones do not predispose female animals to exhibit enhanced or reduced depressive- and anxiety-like behaviours.

Neonatal Exposure to Valproate Induces Long-Term Alterations in Steroid Hormone Levels in the Brain Cortex of Prepubertal Rats

Valproic acid (VPA) is a known drug for treating epilepsy and mood disorders; however, it is not recommended for pregnant women because of its possible teratogenicity. VPA affects neurotransmission and gene expression through epigenetic mechanisms by acting as a histone deacetylase inhibitor and has been used to establish animal models of autism spectrum disorder (ASD). However, studies on the long-term effects of early exposure to VPA on glucocorticoid and neurosteroid synthesis in the brain are lacking. Therefore, this study aimed to investigate the long-term changes in metabolic alterations and gene expression regulation according to sex, using metabolic steroid profiling data from cerebral cortex samples of rats four weeks after VPA exposure (400 mg/kg). In neonatal VPA-exposed models, estradiol levels decreased, and cytochrome P450 19A1 gene (Cyp19a1) expression was reduced in the prepubertal male cortex. Progesterone and allopregnanolone levels decreased, and 3β-hydroxysteroid dehydrogenase 1 gene (Hsd3b1) expression was also downregulated in the prepubertal female cortex. Furthermore, cortisol levels increased, and mRNA expression of the nuclear receptor subfamily 3 group C member 1 gene (Nr3c1) was downregulated in the cortices of both sexes. Unlike the neonatal VPA-exposed models, although a decrease in progestin and estradiol levels was observed in females and males, respectively, no differences were observed in cortisol levels in the cortex tissues of 8-week-old adult rats administered VPA for four weeks. These results indicate that early environmental chemical exposure induces long-term neurosteroid metabolic effects in the brain, with differences according to sex.

Sex-Specific Effect of Obesity on Epiblepharon in Different Age Groups: A Case-Control Study

Obesity has been regarded as a risk factor for several ocular diseases. This study aims to investigate the age- and sex-specific relationship between epiblepharon and obesity in children. A retrospective case-control study was conducted using the Chang Gung Research Database. Children ≤ 18 years of age with epiblepharon were identified from 1 January 2009 to 31 December 2019. Children were classified into three groups: normal, overweight and obese groups. A total of 513 patients and 1026 controls (57.7% males) aged 1 to 18 matched by sex and age were included in the analysis. The median body mass index (BMI) of children with epiblepharon was significantly higher than that of children without epiblepharon (p < 0.001). In the subgroup analysis, among boys aged 4 to 9 years, the BMI in boys with epiblepharon was significantly higher than that in boys without epiblepharon (p < 0.05) and the risk of epiblepahron in overweight/obese boys was significantly higher than in non-overweight boys (OR = 1.74, 95% CI = 1.07-2.82 for age 4 to 6; OR = 3.06, 95% CI = 1.56-6.03 for age 7 to 9). On the other hand, among girls aged 13 to 18 years, the BMI in adolescent girls with epiblepharon was significantly higher than that in the control group (p < 0.05) and overweight/obese girls had a statistically higher risk of persistent epiblepharon than non-overweight girls (OR = 3.70, 95% CI = 1.38-9.97). The association between obesity and epiblepharon varies in strength according to age in a sex-specific manner.

A more than four-fold sex-specific difference of autism spectrum disorders and the possible contribution of pesticide usage in China 1990-2030

Autism spectrum disorders (ASDs) are prevalent in children and adolescents and disproportionately affect males, and the main contributing factors underlying male vulnerability remain widely unknown. Pesticide use is widely reported to be associated with ASD risk, and the cases of pesticide poisoning incidence in rural areas are remarkably higher than those in the urban areas while the prevalence of ASDs in rural areas was higher than that in urban areas and the rate of male pesticide poisoning was significantly higher than female. Thus, pesticide usage may be an important contributing factor for causing sex-specific differences of ASD incidence. ASD burden was analyzed by using the data of ASD number, ASD rate (ASD cases per 100,000 persons) and disability-adjusted life years (DALYs) from 1990 to 2019. The changes from 1990 to 2030 were predicted using autoregressive integrated moving average (ARIMA) in time series forecasting based on the small values of Akaike information criterion and Bayesian information criterion. Finally, the relationship between ASD rate and pesticide usage risk index (PURI) was analyzed via Pearson's correlation coefficient. ASD number, ASD rate and DALYs will be reduced by 45.5% ± 8.2% (t = 9.100 and p = 0.0119), 56.6% ± 10.2% (t = 9.111 and p = 0.0118), and 44.9% ± 7.0% (t = 20.90 and p = 0.0023) from 1990 to 2030 in China. PURI has a strong relationship with ASD rate (rho = 0.953 to 0.988 and p < 0.0001). Pesticide poisoning incidence in males is up to 2-fold higher than that in females. ASD number and DALYs in males are 4-fold higher than those in females. Furthermore, there is growing evidence supporting that males are more susceptible than females to pesticides with sex differences in neurotoxicogenetics. Therefore, pesticide poisoning may be a contributing factor for causing the sex differences of ASD. Much work still needs to be done to confirm that.

Corrigendum: Sex-Specific Differences in the Effect of Free Testosterone on Sarcopenia Components in Older Adults

[This corrects the article DOI: 10.3389/fendo.2021.695614.].

Sex-Specific Differences in the Effect of Free Testosterone on Sarcopenia Components in Older Adults

OBJECTIVE

The association of free testosterone (FT) with sarcopenia and its components is well known in men but incompletely understood in women. We examined the association of baseline FT with the prevalence and incidence of sarcopenia and its components in community-dwelling older adults.

DESIGN

Cross-sectional and longitudinal analysis from the prospective population-based Korean Frailty and Aging Cohort Study.

METHODS

A total of 1,879 community-dwelling older adults aged 70-84 years were enrolled for cross-sectional analysis and 1,583 subjects who participated in the 2-year follow-up survey were included for longitudinal analysis. Baseline FT levels was measured by radioimmunoassay. Skeletal muscle mass, handgrip strength, and physical performance tests were measured at baseline and after 2-year follow-up. Sarcopenia was defined by the diagnostic criteria of the Asian Working Group for Sarcopenia (AWGS).

RESULTS

Continuous FT levels was positively associated with the prevalence of sarcopenia in men (odds ratio [OR]=0.95; 95% confidence interval [CI]=0.89-1.00)] and women (OR=0.64, 95% CI=0.42-0.99) after adjusting for multiple confounders. In prospective analysis, low FT levels was associated with a decrease in handgrip strength in women (β=-0.61; p=0.010) and a reduction in Timed "Up and Go" (TUG) test (β=0.53; p=0.008) in men after 2 years. No significant correlations were found between FT levels and the incidence of sarcopenia.

CONCLUSIONS

Low levels of FT may be a significant determinant of decreases in muscle strength in women and declines in physical performance in men after 2 years. Low FT do not predict loss of muscle mass in both men and women.

Dipeptidyl peptidase 3 modulates the renin-angiotensin system in mice

Dipeptidyl peptidase 3 (DPP3) is a zinc-dependent hydrolase involved in degrading oligopeptides with 4-12 amino acid residues. It has been associated with several pathophysiological processes, including blood pressure regulation, pain signaling, and cancer cell defense against oxidative stress. However, the physiological substrates and the cellular pathways that are potentially targeted by DPP3 to mediate these effects remain unknown. Here, we show that global DPP3 deficiency in mice (DPP3^-/-) affects the renin-angiotensin system (RAS). LC-MS-based profiling of circulating angiotensin peptides revealed elevated levels of angiotensin II, III, IV, and 1-5 in DPP3^-/- mice, whereas blood pressure, renin activity, and aldosterone levels remained unchanged. Activity assays using the purified enzyme confirmed that angiotensin peptides are substrates for DPP3. Aberrant angiotensin signaling was associated with substantially higher water intake and increased renal reactive oxygen species formation in the kidneys of DPP3^-/- mice. The metabolic changes and altered angiotensin levels observed in male DPP3^-/- mice were either absent or attenuated in female DPP3^-/- mice, indicating sex-specific differences. Taken together, our observations suggest that DPP3 regulates the RAS pathway and water homeostasis by degrading circulating angiotensin peptides.

Sex-Specific Differences in HLA Antibodies after Pneumococcal Vaccination in Kidney Transplant Recipients

In transplant recipients vaccination against Streptococcus pneumoniae is recommended to reduce mortality from invasive pneumococcal disease. It is still debated if vaccination in transplant recipients triggers alloresponses. Therefore, it was our aim to define if vaccination with Prevenar 13^®, a 13-valent, conjugated pneumococcal vaccine (Pfizer, New York, NY, USA) that acts T cell dependently, induces human leukocyte antigen (HLA) antibodies in clinically stable kidney transplant recipients. Forty-seven patients were vaccinated once with Prevenar 13^® and HLA antibodies were determined prior to vaccination and at month 1 and 12 thereafter. In parallel, pneumococcal IgG antibodies were measured. Using Luminex™ Mixed Beads technology (One Lambda/Thermo Fisher, Canoga Park, CA, USA) we observed overall no change in HLA antibodies after vaccination. Pneumococcal antibodies increased significantly at month 1 (p < 0.0001) and remained elevated at month 12 (p < 0.005). A more detailed analysis of HLA antibodies showed that in 18 females HLA class I and II antibodies increased significantly at month 1 and 12 (p < 0.05); whereas in 29 males HLA class I and II antibodies tended to decrease. Using Luminex™ Single Antigen Beads assay, no de novo donor-specific HLA antibodies were detected after vaccination. In conclusion, the current data indicate that females may be more susceptible to the induction of (non-specific) HLA antibodies after vaccination.

Sex-specific difference in age distribution of congenital lower eyelid epiblepharon in a Japanese population

PURPOSE

To examine the sex-specific differences in age distribution of Japanese patients with congenital lower eyelid epiblepharon.

STUDY DESIGN

A retrospective, observational study.

METHODS

A total of 291 patients (87 men, 204 women) who underwent modified Hotz for correction of congenital lower eyelid epiblepharon were included in this study. Data on sex, age at surgical intervention, and affected side were collected. Patients' age was classified according to the orbital growth pattern (0-3 years, 4-6 years, 7-12 years, 13-15 years, and ≥ 16 years). The sex-specific difference in age distribution was analysed using Pearson's chi-squared test.

RESULTS

Among male patients, 75 (86.2%) underwent surgery during 4-12 years of age. Only 2 (2.3%) boys had surgery at 13-15 years and 1 had it while he was ≥ 16 years. Among female patients, 11 (5.4%) underwent surgery at 13-15 years and 59 (28.9%) at ≥ 16 years. The age distribution was significantly different between sexes (P < 0.001).

CONCLUSION

Among patients aged ≥13 years, there were more women compared to men. This implies that congenital lower eyelid epiblepharon is more persistent in females and may reflect slower and less orbital growth from 13 years of age and onwards in females. The results suggest that as long as there are no severe corneal complications and no risk for amblyopia, conservative management may be a good option for males since spontaneous resolution is likely to occur. However, for females aged 13 years or more, the threshold for surgical intervention should be lower.

Toll family members bind multiple Spätzle proteins and activate antimicrobial peptide gene expression in Drosophila

The Toll signaling pathway in Drosophila melanogaster regulates several immune-related functions, including the expression of antimicrobial peptide (AMP) genes. The canonical Toll receptor (Toll-1) is activated by the cytokine Spätzle (Spz-1), but Drosophila encodes eight other Toll genes and five other Spz genes whose interactions with one another and associated functions are less well-understood. Here, we conducted in vitro assays in the Drosophila S2 cell line with the Toll/interleukin-1 receptor (TIR) homology domains of each Toll family member to determine whether they can activate a known target of Toll-1, the promoter of the antifungal peptide gene drosomycin. All TIR family members activated the drosomycin promoter, with Toll-1 and Toll-7 TIRs producing the highest activation. We found that the Toll-1 and Toll-7 ectodomains bind Spz-1, -2, and -5, and also vesicular stomatitis virus (VSV) virions, and that Spz-1, -2, -5, and VSV all activated the promoters of drosomycin and several other AMP genes in S2 cells expressing full-length Toll-1 or Toll-7. In vivo experiments indicated that Toll-1 and Toll-7 mutants could be systemically infected with two bacterial species (Enterococcus faecalis and Pseudomonas aeruginosa), the opportunistic fungal pathogen Candida albicans, and VSV with different survival times in adult females and males compared with WT fly survival. Our results suggest that all Toll family members can activate several AMP genes. Our results further indicate that Toll-1 and Toll-7 bind multiple Spz proteins and also VSV, but they differentially affect adult survival after systemic infection, potentially because of sex-specific differences in Toll-1 and Toll-7 expression.

Behavioural Phenotypic Plasticity of Submerged Oviposition in Damselflies (Insecta: Odonata)

Emerald damselfly Lestes sponsa is a common species within the temperate zone, with no special need for protection. The tactic of submerged oviposition is well known from other Odonata species, but has rarely been noticed or described in Lestes sponsa. Our study investigated the tactics of oviposition in this species, and shows that submerged oviposition indeed occurs frequently in Lestes sponsa. We experimentally tested the difference in the roles of males and females during the submerged ovipositional behaviour by combining males/females from submerging populations with males/females from non-submerging populations. We discovered that, whereas submerging males coupling with non-submerging females did not lead to submersion, the opposite combination of pairs submerged. Other patterns of submersions are discussed further in this paper. Our research led to the conclusion that damselflies have the ability to learn and react to different situations in keeping with the learning potential of insects in general.

No Sex-Specific Differences in the Acute Antidepressant Actions of (R)-Ketamine in an Inflammation Model

BACKGROUND

Although previous reports suggest sex-specific differences in the antidepressant actions of (R,S)-ketamine, these differences in the antidepressant actions of (R)-ketamine, which is more potent than (S)-ketamine, are unknown.

METHODS

Saline or (R)-ketamine was administered 23 hours post lipopolysaccharide administration to adult male or female mice. Subsequently, antidepressant effects were assessed using a forced swimming test. Furthermore, the concentration of (R)-ketamine and its 2 major metabolites, (R)-norketamine and (2R,6R)-hydroxynorketamine, was measured in the plasma and brain after the administration of (R)-ketamine in the mice.

RESULTS

(R)-ketamine (10 mg/kg) significantly attenuated the increased immobility time of forced swimming test in the lipopolysaccharide-treated mice. There were no sex-specific differences in the concentrations of (R)-ketamine and its 2 metabolites in the plasma and brain.

CONCLUSIONS

These findings showed no sex-specific differences in terms of the acute antidepressant effects and pharmacokinetic profile of (R)-ketamine.