Association of Serum Prolactin With Type 2 Diabetes Mellitus: A Comparative Cross-Sectional Study From South India

Correlation of Serum Prolactin Levels With Metabolic and Cardiovascular Risk in Greek Women With Polycystic Ovarian Syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disorder among females. PCOS is associated with various metabolic and cardiovascular complications, including insulin resistance, dyslipidemia, and an increased risk of type 2 diabetes mellitus and cardiovascular disease. The role of serum prolactin (PRL) in the development of these complications in PCOS is not well understood.

AIM

This study aims to investigate the correlation between serum PRL levels and metabolic and cardiovascular risk factors in Greek women with PCOS.

METHODS

The study utilized secondary outcomes from a prospectively collected patient database at the Third Department of Obstetrics and Gynecology, Medical School of the University of Athens. Data were collected from patients who visited the Gynecological Endocrinology - Pediatric and Adolescence Endocrinology Outpatient Clinic between January 2007 and December 2015. Measurements of various parameters, including PRL levels, BMI, waist circumference, hormone levels, lipid profiles, and insulin sensitivity, were obtained. Statistical analyses, including Mann-Whitney tests, chi-square tests, Spearman correlations, and multiple linear regression analyses, were conducted using SPSS software (IBM Corp., Armonk, NY, USA).

RESULTS

The study included 247 women with PCOS, with a mean age of 24.7 years. Participants were divided into two groups based on the median PRL level. Women with higher PRL levels (>14.9) had lower BMI and waist circumference, higher levels of certain hormones and insulin sensitivity, and lower levels of fasting insulin, total cholesterol, and total lipids. Factors associated with lower PRL levels included being overweight/obese and smoking more than 10 cigarettes per day. Higher age, BMI, waist circumference, and certain hormone levels were associated with lower PRL levels.

CONCLUSION

The findings suggest a correlation between serum PRL levels and metabolic and cardiovascular risk factors in Greek women with PCOS. Further research is needed to elucidate the role of PRL in the pathophysiology of PCOS and to explore its potential as a diagnostic and therapeutic target.

Effect of honey bee venom on the histological changes of testes and hormonal disturbance in diabetic mice

Background and Aim:

Hyperglycemia associated with hyper- or hypo-insulinemia is a hallmark of type 2 diabetes mellitus, which is firmly linked to decreased male infertility. Recently, bee venom (BV) has shown potential health prosperities, including antidiabetic; however, no study focuses on the effect of BV on male fertility in diabetic conditions. This study aimed to detect the effect of BV on histological and hormonal alteration of the testis in diabetic mice.

Materials and Methods:

Twenty adult male mice were selected and assigned to four groups: Control, diabetic (150 mg/kg alloxan), BV1 (diabetic + 0.5 mg/kg BV), and BV2 (diabetic + 1 mg/kg BV). After 35 days, the serum levels of glucose, insulin, testosterone, follicular-stimulating hormone, luteinizing hormone, and prolactin were estimated. The histological structure of the testes was also evaluated.

Results:

Alloxan-induced hyperglycemia and decreased insulin concentrations were reversed significantly by BV. Furthermore, diabetic mice exhibited various alterations in fertility hormones, while these disturbances were improved considerably to normal concentrations by BV. Similarly, alloxan-induced changes in sperm and testis histological parameters such as motility, viability, abnormality, sperm count, the number and diameter of seminiferous tubules, and the number of Leydig and Sertoli cells were significantly ameliorated to the normal condition by BV. Changes in the number, size, and shape of seminiferous tubules, the number of Leydig and Sertoli cells, and initial degeneration and vacuolization in interstitial cells and spermatogonia and spermatocyte were seen in diabetic mice. All these changes were shifted almost to normal structure by BV.

Conclusion:

The BV could be used as an alternative therapeutic agent that manages the markers related to diabetic conditions concomitant with the improved histological structure of the testes and hormone production to accelerate male fertility.

The interplay between prolactin and cardiovascular disease

Hyperprolactinemia can be caused by several conditions and its effects on the hypothalamic-pituitary-gonadal axis are understood in more detail. Nevertheless, in recent decades, other metabolic effects have been studied and data pointed to a potential increased cardiovascular disease (CVD) risk. A recent study showed a decrease in total and LDL- cholesterol only in men with prolactinoma treated with dopamine agonists (DA) supporting the previous results of a population study with increased CVD risk in men harboring prolactinoma. However, other population studies did not find a correlation between prolactin (PRL) levels and CVD risk or mortality. There is also data pointing to an increase in high-density lipoprotein levels, and decreases in triglycerides, carotid-intima-media thickness, C-reactive protein, and homocysteine levels in patients with prolactinoma on DA treatment. PRL was also implicated in endothelial dysfunction in pre and postmenopausal women. Withdrawal of DA resulted in negative changes in vascular parameters and an increase in plasma fibrinogen. It has been shown that PRL levels were positively correlated with blood pressure and inversely correlated with dilatation of the brachial artery and insulin sensitivity, increased homocysteine levels, and elevated D-dimer levels. Regarding possible mechanisms for the association between hyperprolactinemia and CVD risk, they include a possible direct effect of PRL, hypogonadism, and even effects of DA treatment, independently of changes in PRL levels. In conclusion, hyperprolactinemia seems to be associated with impaired endothelial function and DA treatment could improve CVD risk. More studies evaluating CVD risk in hyperprolactinemic patients are important to define a potential indication of treatment beyond hypogonadism.