Catechol-O-methyltransferase is dispensable for vascular protection by estradiol in mouse models of atherosclerosis and neointima formation

2-Methoxyestradiol inhibits carotid artery intimal hyperplasia induced by balloon injury via inhibiting JAK/STAT axis in rats

Intimal hyperplasia (IH) is a common complication of vascular interventional procedures that leads to narrowing of the vessel lumen. 2-Methoxyestradiol (2ME), an estrogen metabolite, has numerous pharmacological actions, including vasoprotective and antiproliferative activities. The present study aimed to evaluate the potential of 2ME, prepared as a self-nanoemulsifying drug delivery system (SNEDDS), to inhibit IH induced by balloon injury (BI) in the rat carotid artery. The prepared 2ME SNEDDS had a particle size of 119 ± 2.3 nm and a zeta potential of -7.1 ± 1.4 mV. Animals were divided into 5 groups, namely control, sham, BI, BI + 2ME (100 μg/kg), and BI + 2ME (250 μg/kg). The obtained data indicated that 2ME significantly inhibited IH as indicated by the histological and morphometric assessment of the intima, media and lumen areas. This was associated with enhanced expression of Bax and inhibited expression of Bcl2 mRNA. Furthermore, 2ME exhibited significant antioxidant properties as evidenced by prevention of malondialdehyde accumulation as well as superoxide dismutase and catalase enzymatic exhaustion. In addition, 2ME showed significant anti-inflammatory actions as it significantly inhibited vascular content of interleukin-6, tumor necrosis factor-alpha, and nuclear factor-κB. The observed vasoprotective activities of 2ME were accompanied by inhibition of Janus kinase/signal transducers and activators of transcription (JAK/STAT) protein expression. In conclusion, this study revealed that 2ME ameliorates balloon injury-induced IH in rats via suppressing JAK/STAT axis. This may help to develop new strategies to combat IH.

Candidate SNP Markers of Atherogenesis Significantly Shifting the Affinity of TATA-Binding Protein for Human Gene Promoters show stabilizing Natural Selection as a Sum of Neutral Drift Accelerating Atherogenesis and Directional Natural Selection Slowing It

(1) Background: The World Health Organization (WHO) regards atherosclerosis-related myocardial infarction and stroke as the main causes of death in humans. Susceptibility to atherogenesis-associated diseases is caused by single-nucleotide polymorphisms (SNPs). (2) Methods: Using our previously developed public web-service SNP_TATA_Comparator, we estimated statistical significance of the SNP-caused alterations in TATA-binding protein (TBP) binding affinity for 70 bp proximal promoter regions of the human genes clinically associated with diseases syntonic or dystonic with atherogenesis. Additionally, we did the same for several genes related to the maintenance of mitochondrial genome integrity, according to present-day active research aimed at retarding atherogenesis. (3) Results: In dbSNP, we found 1186 SNPs altering such affinity to the same extent as clinical SNP markers do (as estimated). Particularly, clinical SNP marker rs2276109 can prevent autoimmune diseases via reduced TBP affinity for the human MMP12 gene promoter and therefore macrophage elastase deficiency, which is a well-known physiological marker of accelerated atherogenesis that could be retarded nutritionally using dairy fermented by lactobacilli. (4) Conclusions: Our results uncovered SNPs near clinical SNP markers as the basis of neutral drift accelerating atherogenesis and SNPs of genes encoding proteins related to mitochondrial genome integrity and microRNA genes associated with instability of the atherosclerotic plaque as a basis of directional natural selection slowing atherogenesis. Their sum may be stabilizing the natural selection that sets the normal level of atherogenesis.

A second-generation 2-Methoxyestradiol prodrug is effective against Barrett's adenocarcinoma in a mouse xenograft model

2-Methoxyestradiol (2-ME2) is an endogenous metabolite of estradiol. In preclinical models, 2-ME2 is effective against different types of tumors. Unfortunately, only low systemic concentrations of 2-ME2 can be achieved following oral administration, even after very high doses are administered to patients. In an effort to solve this problem, we have now synthesized and tested a new prodrug of 2-ME2 that is water-soluble due to a bioreversible hydrophilic group added at the 3-position and that more effectively resists metabolic inactivation due to an ester moiety added to mask the 17-position alcohol. We are reporting here for the first time that this double prodrug of 2-ME2 is effective as an antiproliferative and anticancer agent for both in vitro and in vivo studies against Barrett esophageal adenocarcinoma (BEAC) and provided greater potency than 2-ME2 in inhibiting the growth of BEAC xenografts. Finally, studies indicate that, like 2-ME2, the 2-ME2-PD1 exhibits anticancer effect through possible disruption of microtubule network.

Sexual dimorphisms in the immune system of catechol-O-methyltransferase knockout mice

The enzyme catechol-O-methyltransferase (COMT) is part of the metabolic pathway of 17β-estradiol, converting 2-hydroxyestradiol to 2-methoxyestradiol. We recently showed that administration of the COMT product 2-methoxyestradiol has anti-inflammatory and anti-osteoporotic effects. We have now investigated whether COMT affects the immune system, by immunologically phenotyping COMT deficient (COMT(-/-)) mice. Immunoglobulin production, T lymphocyte proliferation, NK cell cytotoxicity and oxygen radical production were assessed. In male COMT(-/-)-mice, the total number of T-, and B-lymphocytes from spleen increased but the T-cell proliferative response decreased. The NK cell population shifted toward less mature cells, leaving cytotoxic capacity unaffected. In COMT(-/-)-females, a higher frequency of neutrophils was found but the oxygen radical production was unaltered. In conclusion, only minor changes of the immune system were seen in COMT deficient mice, and the changes were usually seen in males. This study provides clues into how COMT activity, and hence gender differences, affects the immune system.