Model: Male Wistar rats (4-month-old young rats and 24-month-old old rats)
Dosage: Oral administration of the trypsin inhibitor tranexamic acid in drinking water for 14 days at a minimum dose of 0.39 g/kg/day after consuming about 40 mL/day of water

Newly Proposed Aging Mechanism: Digestive Enzymes May Be Eating Us from Within

University of California, San Diego researchers show digestive enzyme leakage from the intestines contributes to organ damage in old rats, offering what may be a new way to explain aging.

(Principal investigator, Geert Schmid-Schönbein | voiceofsandiego.org)

Aging &amp; Longevity

A molecule found in the plasma of exercised mice reverses the brain aging of sedentary mice. 

(Image: UCSF.edu) Senior author Saul Villeda, PhD. 

Model: C57BL/6J mice
Dosage: 500 mg/kg/day of Urolithin A in food

Supplementing with urolithin A prevents age-related hearing loss and mitochondrial dysfunction in mice. 

Brain &amp; Neurons

Model: 5xFAD mice
Dosage: 5-µL sprayed into each nostril at concentrations of 30 × 109/100 µL once weekly for two weeks

Exploring a Nasal Spray that Might Delay Alzheimer’s Progression by Years

Researchers use nano-sized vesicles derived from neural stem cells to preserve cognition as well as reduce brain inflammation and plaque buildup in an Alzheimer’s mouse model.

(An aged woman using an intranasal spray to avert Alzheimer's disease progression | NAD.com)

Studies suggest that supplementation with melatonin may slow brain aging, thereby improving cognition. 

Search Result: Brain aging

Newly Proposed Aging Mechanism: Digestive Enzymes May Be Eating Us from Within

Scientists Identify a Molecule that Mimics the Anti-Aging Effects of Exercise on the Brain

Urolithin Anti-Aging Supplement Prevents Hearing Loss, New Research Shows

Exploring a Nasal Spray that Might Delay Alzheimer’s Progression by Years

Does Melatonin Improve Cognition?