l-Theanine Protects Bladder Function by Suppressing Chronic Sympathetic Hyperactivity in Spontaneously Hypertensive...

Area of Science:

• Urology
• Pharmacology
• Cardiovascular Science

Background:

• Chronic sympathetic hyperactivity is linked to metabolic disturbances and organ damage, notably bladder dysfunction.
• Spontaneously hypertensive rats (SHRs) serve as a relevant animal model for studying bladder dysfunction associated with hypertension.

Purpose of the Study:

• To investigate the potential of l-theanine, a green tea component, in ameliorating bladder dysfunction caused by chronic sympathetic hyperactivity.
• To assess the effects of daily l-theanine consumption on the sympathetic nervous system, bladder function, and oxidative stress in SHRs.

Main Methods:

• SHRs were divided into two groups: one receiving water and the other receiving l-theanine orally for six weeks.
• Evaluations included measurements of blood pressure, serum noradrenaline, vascular structure, bladder function (micturition interval, bladder capacity), bladder strip contractility, and oxidative stress markers (malondialdehyde) in bladder tissue via Western blotting.

Main Results:

• The l-theanine group exhibited significantly lower mean blood pressure, serum noradrenaline levels, and media-to-lumen ratio compared to the water group.
• Administration of l-theanine led to a significantly longer micturition interval and increased bladder capacity.
• Bladder strip contractility was enhanced, and malondialdehyde expression in bladder tissue was significantly reduced in the l-theanine group.

Conclusions:

• Oral l-theanine administration demonstrated a protective effect against bladder dysfunction in SHRs.
• L-theanine may prevent bladder dysfunction by mitigating chronic sympathetic hyperactivity and preserving bladder contractility.
• These findings suggest l-theanine as a potential dietary intervention for managing sympathetic hyperactivity-induced bladder issues.