The genetic association between alpha-2-macroglobulin (A2M) gene deletion polymorphism and low serum A2M concentration in overweight/obese Thais

Alpha-2 macroglobulin activity in SARS-CoV-2 induced infection and in the post-COVID-19 period

The universal proteinase inhibitor α2-macroglobulin (α₂-MG) exhibiting antiviral and immunomodulatory activities, is considered as an important participant in the infectious process. The activity of α₂-MG in the new coronavirus infection and post-covid syndrome (long COVID) has not been studied yet. We examined 85 patients diagnosed with community-acquired bilateral polysegmental pneumonia developed under conditions of a new coronavirus infection SARS-CoV-2. For assessment of the post-COVID period, 60 patients were examined 5.0±3.6 months after the coronavirus infection. Among these patients, 40 people had complications, manifested in the form of neurological, cardiological, gastroenterological, dermatological, bronchopulmonary symptoms. The control group included 30 conditionally healthy individuals with a negative PCR result for SARS-CoV-2 RNA and lack of antibodies to the SARS-CoV-2 virus. The α₂-MG activity in serum samples of patients with coronavirus infection dramatically decreased, up to 2.5% of the physiological level. This was accompanied by an increase in the activity of the α₁-proteinase inhibitor, elastase- and trypsin-like proteinases by 2.0-, 4.4- and 2.6-fold respectively as compared with these parameters in conditionally healthy individuals of the control. In the post-COVID period, despite the trend towards normalization of the activity of inhibitors, the activity of elastase-like and especially trypsin-like proteinases in serum remained elevated. In overweight individuals, the increase in the activity of trypsin-like proteinases was most pronounced and correlated with an increase in the antibody titer to the SARS-CoV-2 virus. In the post-COVID period, the α₂-MG activity not only normalized, but also exceeded the control level, especially in patients with dermatological and neurological symptoms. In patients with neurological symptoms or with dermatological symptoms, the α₂-MG activity was 1.3 times and 2.1 times higher than in asymptomatic persons. Low α₂-MG activity in the post-COVID period persisted in overweight individuals. The results obtained can be used to monitor the course of the post-COVID period and identify risk groups for complications.

Correlation between body mass index and prostate volume in benign prostatic hyperplasia patients undergoing holmium enucleation of the prostate surgery

Background

Benign prostatic obstruction (BPO) due to benign prostatic hyperplasia (BPH) is a leading cause of morbidity in men over the age of 40. This study examined whether there was an association between body mass index (BMI) and pre-operative prostate volume and whether expression of two genes, alpha-2-macroglobulin (A2M) and transforming growth factor beta 3 (TGFB3), was correlated with BMI, pre-operative prostate volume, and age at surgery.

Methods

Medical records of patients who underwent holmium enucleation of the prostate surgery for treatment of BPO were retrospectively reviewed. Surgical specimens were obtained from formalin-fixed paraffin-embedded blocks, and expression of the targeted genes was quantified using a real time PCR approach. Linear regression analysis was performed to assess association between BMI and prostate volume adjusting for demographic characteristics and co-morbidity. Spearman’s correlation was used to examine whether gene expression was correlated with BMI, prostate volume, and age at surgery.

Results

A total of 278 patients were identified, including 62.9% European Americans (n = 175) and 27.7% Hispanic Americans (n = 77). BMI was significantly correlated with prostate volume (Spearman’s rho = 0.123, P = 0.045). In linear regression analysis, BMI was positively associated with prostate volume (β = 0.01, P = 0.004), while hyperlipidemia was negatively associated with prostate volume (β = −0.08, P = 0.02). A trend for a positive association was also observed for diabetes (β = 0.07, P = 0.099). In the race/ethnicity stratified analysis, age at surgery showed a trend for significantly positive association with prostate volume in European Americans (β = 0.005, P = 0.08), but not in Hispanic Americans. Expression of the A2M gene in the stroma was negatively correlated with age at surgery (P = 0.006). A2M expression in the gland was positively correlated with prostate volume among older men (Age ≥ 70, P = 0.01) and overweight men (BMI 25–30, P = 0.04). TGFB3 expression in the gland was positively correlated with BMI (P = 0.007) among older men.

Conclusions

This study demonstrated the positive correlation between BMI and prostate volume. Expression of TGFB3 and A2M was correlated with BMI, prostate volume, and age at surgery.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s12894-020-00753-9.