Endocrine Abstracts

JOINT944

Background: Turner Syndrome (TS) is characterized by complete or partial loss of one X chromosome, leading to a range of physical, cognitive, and neurodevelopmental abnormalities. Therapeutic interventions such as GH and sex steroid therapy have shown promise in addressing these deficits, but their effects on brain structure and pituitary function remain under scrutiny.

Objectives: To investigate the effects of GH and sex steroid therapy on brain structure, pituitary function, and associated clinical outcomes in individuals with TS.

Methods: This review synthesizes findings from studies involving TS patients, comparing brain structure, pituitary function, and clinical outcomes with healthy controls (HC). Data include sample sizes ranging from 9 to 65 individuals, with a focus on neuroimaging, hormonal levels, and cognitive performance metrics.

Detailed Results:

• Brain Structure: TS individuals exhibit smaller hippocampus, caudate, thalamic nuclei, and parieto-occipital brain volumes compared to HC (Murphy et al., 1993). GH and sex steroid therapies influence these metrics, with estrogen deficiency linked to reduced gray and white matter development (Li et al., 2019). Enhanced basal ganglia and cerebellar growth during adolescence was observed with combined therapies (O’Donoghue et al., 2019).

• Pituitary Function: GH therapy increases adrenal steroid responsiveness (Balducci et al., 1998), reduces fat mass, and improves lean body mass (Gravholt et al., 2002). GH-IGF axis irregularities in TS can be normalized with sex hormone replacement (Gravholt et al., 1997).

• Cognitive Outcomes: Oxandrolone, a common adjunct with GH, improves working memory but GH alone does not significantly affect cognitive performance [(Ross et al., 1997)](https://consensus. app; (Ross et al., 2003).

Discussion: GH and sex steroid therapies have significant impacts on TS-associated deficits. GH improves growth and body composition, while sex steroids address estrogen deficiency, critical for neurodevelopment. The findings underscore the importance of therapy timing and individualized approaches to maximize outcomes. Limitations include small sample sizes and heterogeneity in therapy protocols across studies.

Conclusion: GH and sex steroid therapies positively impact brain structure and pituitary function in TS, with combination therapy yielding the most substantial benefits. Tailored interventions and rigorous monitoring are essential to optimize clinical and neurodevelopmental outcomes in TS patients.