Aspectos moleculares dos esteroides sexuais sobre a cartilagem e os ossos

Sex-dependent variation in cartilage adaptation: from degeneration to regeneration

Despite acknowledgement in the scientific community of sex-based differences in cartilage biology, the implications for study design remain unclear, with many studies continuing to arbitrarily assign demographics. Clinically, it has been well-established that males and females differ in cartilage degeneration, and accumulating evidence points to the importance of sex differences in the field of cartilage repair. However, a comprehensive review of the mechanisms behind this trend and the influence of sex on cartilage regeneration has not yet been presented. This paper aims to summarize current findings regarding sex-dependent variation in knee anatomy, sex hormones' effect on cartilage, and cartilaginous degeneration and regeneration, with a focus on stem cell therapies. Findings suggest that the stem cells themselves, as well as their surrounding microenvironment, contribute to sex-based differences. Accordingly, this paper underscores the contribution of both stem cell donor and recipient sex to sex-related differences in treatment efficacy. Cartilage regeneration is a field that needs more research to optimize strategies for better clinical results; taking sex into account could be a big factor in developing more effective and personalized treatments. The compilation of this information emphasizes the importance of investing further research in sex differences in cartilage biology.

Effect of two combinations of low-dose oral contraceptives on adolescent bone mass: A clinical trial with 2 years follow-up

INTRODUCTION

Most contraceptive combinations can interfere with the processes of bone formation and resorption.

AIM

The aim of this study was to evaluate the effect of 2 combinations of low-dose oral hormonal contraceptives (20 µg ethinyl estradiol [EE]/150 mg desogestrel [COC1] or 30 µg EE/3 mg drospirenone [COC2]) on bone mass acquisition in adolescents over 2 years by means of bone densitometry and measurement of biomarkers of bone remodeling.

METHODS

Parallel-group, non-randomized controlled clinical trial of 127 adolescents divided into a control group and 2 groups receiving either COC1 or COC2. The participants were submitted to anthropometric assessment and evaluation of secondary sexual characteristics (Tanner criteria) and bone age. Bone densitometry by dual-energy X-ray absorptiometry and measurement of bone biomarkers (bone alkaline phosphatase, osteocalcin, and C-terminal telopeptide) were performed at baseline and after 24 months.

RESULTS

No significant differences in the variables analyzed were observed between COC1 or COC2 users and the control group at baseline. After 24 months, non-users had incorporated more bone mass (content and density) than either group of contraceptive users. This negative impact was more pronounced in the COC2 group than in the COC1 group. A significant reduction in the percentage values of bone alkaline phosphatase and osteocalcin was observed in users of oral contraceptives.

CONCLUSION

Bone mass acquisition was compromised in adolescent users of combined hormonal contraceptives. The negative impact was more pronounced in adolescents using contraceptives that contain 30 µg EE/3 mg drospirenone.

How is the phase angle associated with total and regional bone mineral density in university athletes?. Physiol Meas 2021;42. [PMID: 34225269 DOI: 10.1088/1361-6579/ac114b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Objective.To investigate how phase angle (PhA) is associated with total and regional bone mineral density (BMD) (femur and lumbar spine) in university athletes.Approach.This cross-sectional study was conducted in Florianópolis, Brazil, with 167 university athletes from different sports (92 males). The PhA was obtained through electrical bioimpedance and BMD was obtained through dual x-ray absorptiometry (DXA). Data on the covariables age, time involved in the sport, type of sport (low, medium and high impact), daily use of oral contraceptives, and vitamin D calcium and/or protein supplementation were obtained through anamnesis, while fat mass and fat- and bone-free mass were obtained through DXA. Simple linear regression and a 5% significance level were used.Main results. In female athletes, PhA was directly associated with total BMD (β: 2.20; 95% CI: 0.43; 3.96) and BMD in the femur (β0.85; 95% CI: -0.23; 1.94) and lumbar spine (β: 1.45; 95% CI: 0.44; 2.46), even after adjusting for the covariates. In male athletes, although PhA was directly associated with regional BMD (femur [β: 0.63; 95% CI: 0.04; 1.22] and lumbar spine [β: 0.64; 95% CI: -0.01; 1.31]) in simple linear regression, this association disappeared when the covariates were added.Significance. PhA was directly associated with total BMD and lumbar spine in female, but not male, athletes.

Association between Bone Mineral Density and Nutritional Status, Body Composition and Bone Metabolism in Older Adults

PURPOSE

To identify an association between bone mineral density (BMD) and nutritional status, body composition and bone metabolism in older patients.

METHODS

Cross-sectional study, involving older adults, with osteopenia/osteoporosis and with normal BMD. The mineral density of the lumbar spine from L1 to L4 and the proximal region of the femur was assessed using dual energy X-ray absorptiometry. Biochemical analyzes were performed of 25(OH)-D, calcium and parathormone. Weight, knee height, and abdominal (AC), mid-upper arm (MUAC) and calf (CC) circumferences were measured. The percentage of body fat (%BF) and Fat-Free Mass (FFM) were quantified by electrical bioimpedance analysis. The Body Mass Index (BMI) was calculated. The statistical analysis used bivariate and multivariate, parametric and/or non-parametric tests, and was considered significant when p <0.05.

RESULTS

Of the total 51 older adults assessed, 30 of them (58.8%) were diagnosed with osteopenia/osteoporosis. Body weight (p = 0.001), BMI (p = 0.001), % BF (p = 0.030) and serum concentrations of 25(OH)-D (p = 0.003) were higher in the group without changes in BMD. BMI and serum levels of 25(OH)-D demonstrated a positive correlation with the BMD of all bone compartments and the AC displayed a positive correlation with the lumbar vertebrae. In the logistic regression models, adjusted for sex and age, the BMI and the serum concentration of 25(OH)-D were presented as a protective factor against osteopenia/osteoporosis.

CONCLUSIONS

Higher body weight, BMI, AC and %BF, and sufficient serum levels of vitamin D, were shown to be promoters of BMD.

Effects of hyperprolactinemia on the tibial epiphyseal plate of mice treated with sex hormones

The aim of this study was to evaluate the effects of metoclopramide-induced hyperprolactinemia on the tibial epiphyseal plate of hormone-treated oophorectomized mice. For this purpose, 18 animals with intact ovaries were allocated to two groups, M (metoclopramide) and V (vehicle). One hundred and eight oophorectomized animals were allocated to 12 subgroups: Oophx/V (vehicle); Ooph/M (metoclopramide); Oophx/V + E (vehicle + estradiol); Oophx/M + E (metoclopramide + estradiol); Oophx/V + P (vehicle + progesterone); Oophx/M + P (metoclopramide + progesterone); Oophx/V + T (vehicle + testosterone); Oophx/M + T (metoclopramide + testosterone); Oophx/V + E + P (Vehicle + estradiol + progesterone); Oophx/M + E + P (metoclopramide + estradiol + progesterone); Oophx/V + E + P + T (vehicle + estradiol + progesterone + testosterone); Oophx/M + E + P + T (metoclopramide + estradiol + progesterone + testosterone). After a 50-day treatment was performed histomorphometric and immunohistochemical cell death analysis. In the epiphyseal plate of the hyperprolactinemic and/or oophorectomized animals, cell proliferation and bone formation decreased, inducing intensified cell death. In the sex steroid-treated animals, estrogen boosted cell proliferation; progesterone, bone formation and testosterone, both cell proliferation and bone formation. These findings suggest that oophorectomy and hyperprolactinemia changed epiphyseal plate morphology causing cartilage degeneration. Treatment with combined sex steroids may diminish such deleterious effects.

Glucosamine and chondroitin sulfate association increases tibial epiphyseal growth plate proliferation and bone formation in ovariectomized rats

OBJECTIVE

The growth plate consists of organized hyaline cartilage and serves as a scaffold for endochondral ossification, a process that mediates longitudinal bone growth. Based on evidence showing that the oral administration of glucosamine sulfate (GS) and/or chondroitin sulfate (CS) is clinically valuable for the treatment of compromised articular cartilage, the current study evaluated the effects of these molecules on the tibial epiphyseal growth plate in female rats.

METHOD

The animals were divided into two control groups, including vehicle treatment for 45 days (GC45) and 60 days (GC60) and six ovariectomized (OVX) groups, including vehicle treatment for 45 days (GV45), GS for 45 days (GE45GS), GS+CS for 45 days (GE45GS+CS), vehicle for 60 days (GV60), GS for 60 days (GE60GS) and GS+CS for 60 days (GE60GS+CS). At the end of treatment, the tibias were dissected, decalcified and processed for paraffin embedding. Morphological and morphometric methods were employed for analyzing the distal tibial growth plates using picrosirius red staining and the samples were processed for histochemical hyaluronan detection. Morphometric analyses were performed using the 6.0ProPlus® Image system.

RESULTS

Notably, after 60 days of treatment, the number of proliferative chondrocytes increased two-fold, the percentage of remaining cartilage increased four-fold and the percentage of trabecular bone increased three-fold in comparison to the control animals.

CONCLUSION

GS and CS treatment drugs led to marked cellular proliferation of the growth plate and bone formation, showing that drug targeting of the tibial epiphyseal growth plate promoted longitudinal bone growth.

Physiotherapeutic approach in early and late post-menopausal Brazilian women

To evaluate changes in joints after physiotherapy in post-menopausal women, specifically to identify clinical responses to the measurements of flexibility, functional capacity and joint pain in early and late post-menopausal women at a multi-disciplinary health education programme. A total of 69 women participated in the Integral Program for the Attention to Climacteric Women at the Department of Gynecology - Federal University of Sao Paulo and were sorted into two groups of early (n = 32) and late (n = 37) post-menopause. The average age of menopause was 47.9 ± 5.6 years. The Blatt Kupperman Menopausal Index scores for the early (baseline = 12.8 ± 6.1) and late (baseline = 14.1 ± 7.7) post-menopausal groups after the programme were 8.4 ± 7.1 and 9.4 ± 8.1, respectively. Both groups presented improvements regarding functional capacity (p < 0.01) and complaints of pain (p < 0.001) after the intervention. The group of early post-menopausal women had better flexibility for hip flexion (p < 0.001), and the late post-menopausal group showed greater improvement in shoulder flexion (p < 0.001), extension (p < 0.001) and elbow flexion (p < 0.001). After multi-disciplinary approach, both early and late post-menopausal groups experienced decrease in intensity of climacteric symptoms, reduction in pain intensity and improvement in functional capacity, but the flexibility was different between both the groups.