Longevity Medicine’s Peptides Craze: Evidence, Delivery Challenges, and Expert Opinions

Advocates say peptides offer significant benefits against aging, while researchers warn that these claims outpace the evidence.

(Peptides are often injected with a syringe | Harvard Health)

Proponents say peptides offer significant effects against aging, while skeptical scientists say these claims outpace the evidence.

Aging &amp; Longevity

<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. 


<p>Model: Skin, arterial, and lens tissue from donors between the ages of 20 and 25 and also 75<br />
Dosage: 5 µM solution of CMLase, incubated overnight</p>


Bioengineered Enzyme Shows Ability to Reverse Molecular Aging in Human Tissue

An engineered enzyme reverses age-related protein damage that researchers have long thought irreversible in human eye, skin, and artery tissues.

(A bioengineered enzyme [purple structure] cleaves a prevalent type of AGE [brown glob] on protein residues that are part of protein filaments [dull green chains] | The Scientist)

A bioengineered enzyme reverses age-related protein damage, long thought of as irreversible damage, in human lens, skin, and artery tissues.

Basic Research

<p><span style="font-weight: 400;">Model: Male Wistar rats </span></p>
<p><span style="font-weight: 400;">Dosage: 1.5 g/kg/day of orally administered glycine for 5 months </span></p>


Glycine, an amino acid shown to extend the lifespan of mice, moderately extends the lifespan of flies and counters brain and muscle degeneration in aged rats. 

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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.


Search Result: Collagen

Longevity Medicine’s Peptides Craze: Evidence, Delivery Challenges, and Expert Opinions

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

New Research: Bioengineered Enzyme Shows Ability to Reverse Molecular Aging in Human Tissue

Glycine Extends Life & Counters Brain and Muscle Degeneration, New Study Shows

Dasatinib and Quercetin Delay Early-Onset Disc Degeneration in Mice