Sex-specific endothelial dysfunction induced by high-cholesterol diet in rats: The role of protein tyrosine kinase and nitric oxide

The Mechanism Involved in the Inhibition of Resveratrol and Genistein on the Contractility of Isolated Rat Uterus Smooth Muscle

PURPOSE

This study aimed to compare the effects of the phytoestrogens resveratrol (RES) and genistein (GEN) on the contractility of isolated uterine smooth muscle from rats, focusing on both spontaneous and stimulated contractions, and to investigate the underlying mechanisms.

METHODS

Uterine strips were suspended vertically in perfusion chambers containing Kreb's solution, various concentrations of RES and GEN were added to the ex vivo uterine strips, and contractions were measured before and after incubation with RES or GEN.

RESULTS

(1) Both RES and GEN inhibited K+-induced contractions in a dose-dependent manner; the β/β2-adrenoceptor antagonist propranolol (PRO), ICI118551, the ATP-dependent K+ channel blocker glibenclamide (HB-419) and the NO synthase inhibitor N-nitro-L-arginine (L-NNA) diminished the inhibitory effects of RES and GEN on K+-induced contractions. (2) RES and GEN also dose-dependently inhibited PGF2α-induced uterine contractions. (3) The inhibitory effects of RES and GEN were observed in spontaneous contractile activities as well; PRO, ICI118551, HB-419 and L-NNA attenuated the inhibitory effects of RES and GEN on the spontaneous contractions of isolated uterine muscle strips. (4) RES and GEN significantly decreased the cumulative concentration response of Ca2+ and shifted the Ca2+ cumulative concentration-response curves to the right in high-K+ Ca2+-free Kreb's solution. (5) RES and GEN markedly reduced the first phasic contraction induced by oxytocin, acetylcholine, and prostaglandin F2α but did not alter the second phasic contraction caused by CaCl2 in Ca2+-free Kreb's solution.

CONCLUSIONS

RES and GEN can directly inhibit both spontaneous and activated contractions of isolated uterine smooth muscle. The mechanisms underlying the inhibitory effects of RES and GEN likely involve β adrenergic receptor activation, reduced Ca2+ influx and release, the activation of ATP-dependent K+ channels and increased NO production.

Cardiometabolic Risk Factors Associated With Type 2 Diabetes Mellitus: A Mechanistic Insight

A complex metabolic condition referred to as Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance (IR) and decreased insulin production. Obesity, dyslipidemia, hypertension, and chronic inflammation are just a few of the cardiometabolic illnesses that people with T2DM are more likely to acquire and results in cardiovascular issues. It is essential to comprehend the mechanistic insights into these risk variables in order to prevent and manage cardiovascular problems in T2DM effectively. Impaired glycemic control leads to upregulation of De novo lipogenesis (DNL), promote hepatic triglyceride (TG) synthesis, worsening dyslipidemia that is accompanied by low levels of high density lipoprotein cholesterol (HDL-C) and high amounts of small, dense low-density lipoprotein cholesterol (LDL-C) further developing atherosclerosis. By causing endothelial dysfunction, oxidative stress, and chronic inflammation, chronic hyperglycemia worsens already existing cardiometabolic risk factors. Vasoconstriction, inflammation, and platelet aggregation are caused by endothelial dysfunction, which is characterized by decreased nitric oxide production, increased release of vasoconstrictors, proinflammatory cytokines, and adhesion molecules. The loop of IR and endothelial dysfunction is sustained by chronic inflammation fueled by inflammatory mediators produced in adipose tissue. Infiltrating inflammatory cells exacerbate inflammation and the development of plaque in the artery wall. In addition, the combination of chronic inflammation, dyslipidemia, and IR contributes to the emergence of hypertension, a prevalent comorbidity in T2DM. The ability to target therapies and management techniques is made possible by improvements in our knowledge of these mechanistic insights. Aim of present review is to enhance our current understanding of the mechanistic insights into the cardiometabolic risk factors related to T2DM provides important details into the interaction of pathophysiological processes resulting in cardiovascular problems. Understanding these pathways will enable us to create efficient plans for the prevention, detection, and treatment of cardiovascular problems in T2DM patients, ultimately leading to better overall health outcomes.