Impact of Gender on the Association between Low Serum Prolactin and Left Ventricular Mass in Subjects with Prediabetes

The influence of diabetes and prediabetes on left heart remodeling: A population-based study

BACKGROUND

Diabetes was regarded as an independent risk factor for abnormal left heart remodeling. However, there was lacking population-based data on the relationship of glucose status with left ventricular hypertrophy (LVH) or left atrial enlargement (LAE). This study intended to clarify the influence of diabetes and prediabetes on the prevalence and incidence of LVH and LAE based on a northeast rural population of China.

METHODS

We analyzed clinical, laboratory and echocardiographic data of a total of 2824 participants aged over 35 years from a population-based prospective cohort NCRCHS study with 2 years of follow-up, which was carried out in rural areas of northeast China. All measurements were performed according to standardized protocols.

RESULTS

There were 2179 controls, 342 subjects with prediabetes and 303 ones with diabetes. The baseline distribution of LAD, IVSd, LVIDd, LVIDs, LVMI, E wave, A wave, E/A, E/e', diastolic dysfunction, LVEDV, LVESV and SV was significantly different among three groups (all P_trend<0.05). After the adjustment for age, gender, BMI, waist circumference, heart rate, hypertension and dyslipidemia, glucose status remained associated with LVIDd and E/e' (all P < 0.05). At baseline, diabetes was independently related to the prevalence of LVH (OR = 1.53; 95%CI = 1.12-2.10; P < 0.01) and LAE (OR = 1.71; 95%CI = 1.19-2.43; P < 0.01) in the overall population, and the same significant results were also found in gender specific subgroups. During the 2-year follow-up, Cox regression models revealed that baseline diabetes had an independent association with the incidence of LAE in the total subjects (HR = 1.83; 95%CI = 1.10-3.06; P = 0.02) and females (HR = 1.90; 95%CI = 1.05-3.46; P = 0.04) after adjusting the potential confounders.

CONCLUSION

Diabetes, but not prediabetes, is an independent predictor for the prevalence of LVH and LAE, and for the new-onset LAE, it should be considered in the assessment of diabetes and cardiac structural remodeling.

The regulatory effect of bromocriptine on cardiac hypertrophy by prolactin and D2 receptor modulation

BACKGROUND

Bromocriptine, a dopamine agonist, used for the treatment of hyperprolactinemia, type 2 diabetes, ovarian hyper-stimulation syndrome, has also effects on the cardiac remodeling process, but the mechanism of action is unknown. The aim of this work was to determinate the effect during hypertrophic process through molecular mechanisms that include prolactin receptor (Prlr) and receptor of dopamine 2 (D2 r) expression.

METHODS

We used a model of cardiac hypertrophy induced by an aortocaval fistula (ACF) surgery in rats. Protein concentrations of D2 r and Prlr were determined by western blotting. The treatment consisted in water (control), captopril (50 mg/kg/day), bromocriptine (3 mg/kg/day), and ACF group (n = 6 per group).

RESULTS

Our results showed that bromocriptine treatment decreases the hypertrophy index. Treatment with bromocriptine increases the protein expression of Prlr and D2 r in the cardiac tissue of rats with cardiac hypertrophy.

CONCLUSIONS

We concluded that bromocriptine has a protective effect on cardiac hypertrophy, and due to this effect, it may modulate the expression of Prlr and D2 r, which are involved in the development of cardiac hypertrophy.