<p><span style="font-weight: 400;">Model: Female Balb/c mice exposed to ultraviolet radiation </span></p>
<p><span style="font-weight: 400;">Dosage: 2%, 5%, 7.5%, or 12.5% of nicotinamide (weigh</span><i><span style="font-weight: 400;">t</span></i><span style="font-weight: 400;">/volume) applied topically, once daily, five times per week </span></p>


The NAD+ (nicotinamide adenine dinucleotide) precursor nicotinamide prevents skin aging, in part by targeting age-promoting senescent cells in mice. 


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<p class="PDq2pG_selectionAnchorContainer" data-start="0" data-end="125">Model: 4-week-old <span class="hover:entity-accent entity-underline inline cursor-pointer align-baseline"><span class="whitespace-normal">SM/J</span></span> mice (with <span class="hover:entity-accent entity-underline inline cursor-pointer align-baseline"><span class="whitespace-normal">C57BL/6J</span></span> comparison mice)</p>
<p data-start="127" data-end="279" data-is-last-node="" data-is-only-node="">Dosage: Weekly intraperitoneal injections of 40 mg/kg Navitoclax or 5 mg/kg Dasatinib + 50 mg/kg Quercetin from 4 to 6–8 or 17 weeks of age.</p>
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Dasatinib and Quercetin Delay Early-Onset Disc Degeneration in Mice

Researchers find that clearing senescent cells preserves disc structure and slows early-onset disc degeneration in mice.


Aging &amp; Longevity

<p><span style="font-weight: 400;">Participants: Healthy, overweight older adults </span></p>
<p><span style="font-weight: 400;">Dosage: 6 mg/day of spermidine supplemented orally for 13 weeks </span></p>


Oxford scientists find that spermidine, a naturally occurring molecule that declines with age, rejuvenates aging immune cells and improves vaccine protection in older adults. 


Study conducted at the University of Oxford in England. 

Immunity

<p>Participants: Sedentary older adults </p>
<p>Dosage: 6 mg/week of rapamycin </p>


In older adults, the FDA-approved drug rapamycin, associated with prolonging lifespan, blunts improvements in physical performance.

Skin &amp; Muscle

Harvard: Microbiome Depletion Rejuvenates the Aging Brain

Harvard researchers find that aged mice lacking gut bacteria exhibit a brain more like that of young mice. 

The Principal Investigator of the study, Dr. Lee Rubin (image: harvard.edu). 

Search Result: Senescence

NAD+ Booster Nicotinamide Counters Skin Aging and Cell Senescence, New Study Shows

Dasatinib and Quercetin Delay Early-Onset Disc Degeneration in Mice

Anti-Aging Spermidine Boosts Immune System, New Study Shows

Rapamycin and Exercise: New Study Finds Potential Performance Decline

New Harvard Study: Microbiome Depletion Rejuvenates the Aging Brain