Adjacent Evidence Brief: Growth differentiation factor 11

Adjacent Evidence Brief: Growth differentiation factor 11

Abstract

Evidence-honesty note: 31/48 retained sources are coded as null or no extracted directional signal; this corpus is non-supportive for clinical efficacy claims and hypothesis-generating only. Source-bundle reconciliation note: Directional coding is conservative claim-level coding from extracted claim records, not a statement that the source texts contain no directional findings; source-level positive, negative, or unclear findings should be interpreted through the coded outcome class, directness, and claim-count fields. The retained evidence has no direct interventional hard-endpoint evidence; indirect, review-level, adjacent, or mechanistic sources are used only to bound interpretation. The conclusion therefore does not support broad causal, clinical, or policy claims.

This paper synthesizes evidence on Growth differentiation factor 11 across 48 included source papers and 2684 high-confidence extracted claims.

The evidence profile contains no sources classified primarily as direct interventional hard-endpoint evidence, 39 adjacent clinical sources, and 9 mechanistic or model-system sources, with 152 cross-study disagreements across the evidence base.

Positive study-level signals are not the dominant direction in any outcome class; null signals are summarized in the contextual adjacent evidence, cardiometabolic, and muscle function outcome classes; negative signals are not the dominant direction in any outcome class; mixed or heterogeneous signals are summarized in the mechanism, mortality and survival, frailty, and immune and inflammation outcome classes. The paper therefore interprets the corpus as a tiered evidence profile rather than as a single pooled effect.

The conclusion is that Growth differentiation factor 11 should be treated as a bounded geroscience hypothesis: the retained clinical and adjacent evidence profile defines the scope for targeted testing, while mixed and null findings limit any unqualified anti-aging claim.

Results

Evidence domain	Corpus slice	Strongest signal	Directness	Main limitation
Contextual Adjacent Evidence	n=31; claims=1456	no extracted directional signal in 22/31 sources	31 indirect	limited corpus depth in this outcome class
Mechanism	n=6; claims=638	unclear signal in 2/6 sources	6 mechanistic	limited corpus depth in this outcome class
Cardiometabolic	n=4; claims=100	no extracted directional signal in 4/4 sources	3 indirect; 1 mechanistic	limited corpus depth in this outcome class
Muscle Function	n=3; claims=159	no extracted directional signal in 2/3 sources	1 indirect; 1 mechanistic; 1 review	limited corpus depth in this outcome class
Mortality and Survival	n=2; claims=240	no extracted directional signal in 1/2 sources	2 indirect	limited corpus depth in this outcome class
Frailty	n=1; claims=51	mixed signal in 1/1 sources	1 mechanistic	single-source slice; hypothesis-generating
Immune and Inflammation	n=1; claims=40	unclear signal in 1/1 sources	1 indirect	single-source slice; hypothesis-generating

Outcome-class note: Contextual Adjacent Evidence denotes background, boundary-condition, or adjacent-outcome sources. It is not pooled with direct outcome evidence; these sources bound scope, safety, methods, and translation rather than serving as equal-weight support for the main efficacy claim.

This evidence brief reports outcome packets as a map of retained evidence rather than as a full journal Results narrative or pooled effect estimate.

Contextual Adjacent Evidence Outcomes

31 included sources were assigned to this outcome class. Directional coding: mixed=1, negative=4, null=22, positive=2, unclear=2. Directness coding: indirect=31.

Mechanism Outcomes

6 included sources were assigned to this outcome class. Directional coding: negative=2, null=2, unclear=2. Directness coding: mechanistic=6.

Cardiometabolic Outcomes

4 included sources were assigned to this outcome class. Directional coding: null=4. Directness coding: indirect=3, mechanistic=1.

Muscle Function Outcomes

3 included sources were assigned to this outcome class. Directional coding: null=2, unclear=1. Directness coding: indirect=1, mechanistic=1, review=1.

Mortality Survival Outcomes

2 included sources were assigned to this outcome class. Directional coding: mixed=1, null=1. Directness coding: indirect=2.

Frailty Outcomes

1 included source were assigned to this outcome class. Directional coding: mixed=1. Directness coding: mechanistic=1.

Immune Outcomes

1 included source were assigned to this outcome class. Directional coding: unclear=1. Directness coding: indirect=1.

Limitations

Verification note: Reference-only or no-abstract records are treated as verification-limited context, not as equal-weight support for the main claim.

The curated corpus contains no long-term randomized controlled trial of GDF11 administration in non-diabetic older adults, and it likewise lacks any mortality endpoint trial powered to detect the hard outcomes (all-cause mortality, incident cardiovascular events, incident cancer) on which the anti-aging claim ultimately rests. Without at least one large, long-horizon RCT in healthy aging, the headline conclusion that "GDF11 has context-dependent effects on aging biology" cannot be anchored to the endpoint standard required for a clinical claim.

A non-trivial fraction of the headline outcomes rests on a single source and therefore cannot be cross-validated within the corpus.

Population specificity constrains the external validity of the synthesis in several directions. Women, non-European ancestry groups, and frail community-dwelling older adults meeting EWGSOP2 sarcopenia cutoffs (Cruz-Jentoft 2019: grip strength <27 kg for men, <16 kg for women) are not represented as enrollment strata, and the rodent dosing ranges (e. For example, Moigneu 2023 at 1 mg/kg, Lu 2019 at 1 mg/kg) do not translate to a defined human-equivalent dose.

In animal/preclinical evidence, several clinically relevant endpoints were not measured at all. Gait speed — a canonical functional marker with reference values such as 0.8 m/s (Studenski 2011) and a 0.1 m/s meaningful change (Perera 2006) — does not appear in any source. Incident diabetes, glycemic control against the 7% HbA1c target (ADA 2024), and BMI-stratified obesity outcomes (WHO 2000: 25 kg/m² overweight, 30 kg/m² obesity) appear only as mechanistic context (Lu 2019; Walker 2020) and not as adjudicated trial endpoints. The corpus therefore cannot speak to whether GDF11 modification would shift any of the standard geriatric or metabolic endpoints used in clinical practice.

Several clinically relevant claims are supported only by mechanistic evidence, leaving a documented mechanism-to-clinic gap. Pending further trials that resolve the 152 surfaced tensions, the responsible clinical posture is to treat GDF11 as a hypothesis-generating biomarker and a promising but unproven therapeutic target.

What This Synthesis Adds

This synthesis maps 48 included sources on GDF11 across 7 outcome classes and 152 cross-study disagreements. It separates endpoint-specific evidence from broad geroprotection claims so that favorable biomarker signals are not treated as proof of durable healthspan benefit.

Across 48 curated reference papers, the evidence base for GDF11 shows a context-dependent profile. Positive signals appear in: contextual other. Negative signals appear in: contextual other, mechanism. Null findings dominate: contextual other, cardiometabolic. The synthesis surfaces cross-study disagreements across outcome classes — see Cross-Domain Synthesis. The GDF11 anti-aging case as currently constituted is incomplete: mechanistic plausibility coexists with mixed or sparse human-RCT evidence, and the boundary conditions remain to be established.

The strongest unresolved contrast is the disagreement between Elliott 2017 and Frohlich 2020 on contextual adjacent evidence (severity 5/5), which defines the boundary condition future studies must test rather than smooth over.

In animal/preclinical evidence, prior reviews in the corpus (Smith 2015) emphasize convergent signals on GDF11. This synthesis adds a design-level evidence-weighting layer and an explicit cross-study disagreement map, keeping boundary conditions visible instead of averaging them away in narrative summary.

Boundary-Condition Matrix

Evidence domain	Direct sources	Indirect / mechanism sources	Direction profile	Interpretation boundary
cardiometabolic	0	4	null	direct interventional hard-endpoint gap
frailty	0	1	mixed	direct interventional hard-endpoint gap
mechanism	0	6	negative, null, unclear	conflict-resolution gap
muscle function	0	3	null, unclear	direct interventional hard-endpoint gap
immune and inflammation	0	1	unclear	direct interventional hard-endpoint gap
contextual adjacent evidence	0	31	mixed, negative, null, positive, unclear	conflict-resolution gap
mortality and survival	0	2	mixed, null	direct interventional hard-endpoint gap

Evidence-Gap Priority

Priority	Gap	Rationale
P1	cardiometabolic: direct interventional hard-endpoint gap	0 direct and 4 indirect sources; direction profile: null
P2	frailty: direct interventional hard-endpoint gap	0 direct and 1 indirect source; direction profile: mixed
P3	mechanism: conflict-resolution gap	0 direct and 6 indirect sources; direction profile: negative, null, unclear
P4	muscle function: direct interventional hard-endpoint gap	0 direct and 3 indirect sources; direction profile: null, unclear
P5	immune and inflammation: direct interventional hard-endpoint gap	0 direct and 1 indirect source; direction profile: unclear

Next-Study Design Recommendation

The next high-yield study for GDF11 should target the cardiometabolic evidence gap, pre-register the primary endpoint, separate clinical from mechanistic endpoints, preserve safety and adherence capture, and include an analysis plan that can falsify the current boundary-condition claim rather than only confirming a favorable direction. Minimum useful design: at least 200 participants per arm, a priority population of adults or older adults with baseline risk in the target outcome domain, and follow-up lasting at least 12 months; shorter or smaller studies should be treated as hypothesis-generating.

Evidence Snapshot

The manuscript foregrounds the load-bearing evidence; the full evidence tables remain in the supplement.

Load-Bearing Included Studies

• Additional corpus sources included animal/preclinical evidence; Smith 2015; tier=B1; directness=review; endpoint=muscle function; direction=unclear.
• Wang 2023; tier=B2; directness=indirect; endpoint=contextual adjacent evidence; direction=unclear; representative statistic=P = 0.000.
• Walker 2025; tier=B2; directness=indirect; endpoint=mortality survival; direction=mixed; representative statistic=P < 0.001.
• Schon 2023; tier=B2; directness=indirect; endpoint=contextual adjacent evidence; direction=mixed; representative statistic=P < 0.001.
• Hung 2024; tier=B2; directness=indirect; endpoint=contextual adjacent evidence; direction=null.
• Wang 2021; tier=B2; directness=indirect; endpoint=contextual adjacent evidence; direction=null; representative statistic=P = 0.1590.
• Bajikar 2023; tier=B2; directness=indirect; endpoint=contextual adjacent evidence; direction=null.
• Anon-Hidalgo 2019; tier=B2; directness=indirect; endpoint=contextual adjacent evidence; direction=null; representative statistic=P = 0.053.
• Guo 2025; tier=B2; directness=indirect; endpoint=contextual adjacent evidence; direction=unclear; representative statistic=P < 0.0001.
• Cai 2023; tier=B2; directness=indirect; endpoint=contextual adjacent evidence; direction=null; representative statistic=P = 0.080.

Source Classification Map

Each retained source is mapped to its public evidence role so the evidence landscape can be checked without opening the supplement.

• GDF11 Does Not Rescue Aging-Related Pathological Hypertrophy: outcome=muscle function; directness=review; tier=B1; direction=unclear; claims=2.
• GDF11 slows excitatory neuronal senescence and brain ageing by repressing p21: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=unclear; claims=305.
• Activated GDF11/8 subforms predict cardiovascular events and mortality in humans: outcome=mortality survival; directness=indirect; tier=B2; direction=mixed; claims=218.
• Acute endurance exercise modulates growth differentiation factor 11 in cerebrospinal fluid of healthy young adults: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=mixed; claims=136.
• Protogenin facilitates trunk-to-tail HOX code transition via modulating GDF11/SMAD2 signaling in mammalian embryos: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=106.
• Loss of Growth Differentiation Factor 11 Shortens Telomere Length by Downregulating Telomerase Activity: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=101.
• MeCP2 regulates Gdf11 , a dosage-sensitive gene critical for neurological function: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=99.
• Circulating GDF11 levels are decreased with age but are unchanged with obesity and type 2 diabetes: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=86.
• GDF11-secreting cell transplant efficiently ameliorates age-related pulmonary fibrosis: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=unclear; claims=69.
• Myogenic differentiation of human myoblasts and Mesenchymal stromal cells under GDF11 on Poly-ɛ-caprolactone-collagen I-Polyethylene-nanofibers: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=65.
• GDF11 inhibits adipogenesis and improves mature adipocytes metabolic function via WNT/β‐catenin and ALK5/SMAD2/3 pathways: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=negative; claims=59.
• GDF11 induces mild hepatic fibrosis independent of metabolic health: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=positive; claims=53.
• GDF11 alleviates glucocorticoid-induced osteonecrosis of the femoral head by regulating angiogenesis via the PI3K-AKT-eNOS pathway: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=53.
• Growth differentiation factor 11 attenuates cardiac ischemia reperfusion injury via enhancing mitochondrial biogenesis and telomerase activity: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=positive; claims=52.
• GDF11 protects against mitochondrial-dysfunction-dependent NLRP3 inflammasome activation to attenuate osteoarthritis: outcome=immune; directness=indirect; tier=B2; direction=unclear; claims=40.
• Growth differentiation factor 11 attenuates liver fibrosis via expansion of liver progenitor cells: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=31.
• Lifelong exercise, but not short‐term high‐intensity interval training, increases GDF 11, a marker of successful aging: a preliminary investigation: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=negative; claims=30.
• GDF11 promotes osteogenesis as opposed to MSTN, and follistatin, a MSTN/GDF11 inhibitor, increases muscle mass but weakens bone: outcome=muscle function; directness=indirect; tier=B2; direction=null; claims=28.
• Investigating and correcting a rare pathogenic mutation in GDF11: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=26.
• Hapln1 promotes dedifferentiation and proliferation of iPSC-derived cardiomyocytes by promoting versican-based GDF11 trapping: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=23.
• GDF11 upregulation independently predicts shorter overall-survival of uveal melanoma: outcome=mortality survival; directness=indirect; tier=B2; direction=null; claims=22.
• Longitudinal Relationship Between Growth Differentiation Factor 11 and Physical Activity in Chronic Obstructive Pulmonary Disease: outcome=cardiometabolic; directness=indirect; tier=B2; direction=null; claims=22.
• Evaluation of potential aging biomarkers in healthy individuals: telomerase, AGEs, GDF11/15, sirtuin 1, NAD+, NLRP3, DNA/RNA damage, and klotho: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=20.
• Growth differentiation factor 11 accelerates liver senescence through the inhibition of autophagy: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=negative; claims=20.
• Heterozygous loss-of-function variants significantly expand the phenotypes associated with loss of GDF11: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=17.
• Growth differentiation factor 11 (GDF11) has pronounced effects on skin biology: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=16.
• Growth differentiation factor 11 inhibits adipogenic differentiation by activating TGF‐beta/Smad signalling pathway: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=16.
• GDF11 inhibits the malignant progression of hepatocellular carcinoma via regulation of the mTORC1‑autophagy axis: outcome=cardiometabolic; directness=indirect; tier=B2; direction=null; claims=14.
• Role of growth differentiation factor 11 in development, physiology and disease: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=12.
• Endogenous GDF11 regulates odontogenic differentiation of dental pulp stem cells: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=11.
• Association of a variant upstream of growth differentiation factor 11 ( GDF11 ) on carcass traits in crossbred beef cattle: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=11.
• PPAR α Targeting GDF11 Inhibits Vascular Endothelial Cell Senescence in an Atherosclerosis Model: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=negative; claims=10.
• Exosome-transmitted miR-3124-5p promotes cholangiocarcinoma development via targeting GDF11: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=10.
• Bioinformatics network analyses of growth differentiation factor 11: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=9.
• Novel insights into the pleiotropic health effects of growth differentiation factor 11 gained from genome-wide association studies in population biobanks: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=4.
• GDF11 inhibits adipogenesis of human adipose-derived stromal cells through ALK5/KLF15/β-catenin/PPARγ cascade: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=3.
• Expression profiling by high-throughput sequencing reveals GADD45, SMAD7, EGR-1 and HOXA3 activation in Myostatin (MSTN) and GDF11 treated myoblasts: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=2.
• Anti-Aging Effects of GDF11 on Skin: outcome=cardiometabolic; directness=indirect; tier=B2; direction=null; claims=2.
• Similar sequences but dissimilar biological functions of GDF11 and myostatin: outcome=contextual adjacent evidence; directness=indirect; tier=B2; direction=null; claims=1.
• Dietary intake of GDF11 delays the onset of several biomarkers of aging in male mice through anti-oxidant system via Smad2/3 pathway: outcome=mechanism; directness=mechanistic; tier=C1; direction=null; claims=296. Translational relevance to humans remains uncertain.

Classification Criteria

• Outcome class is assigned from the source's bound endpoint, population, and claim text; adjacent/background sources are separated from clinical outcome slices.
• Directness is coded as direct only when a source tests the topic against a clinically proximate outcome in the relevant population; a qualifying direct source would be a human interventional or hard-endpoint study of the topic itself. Indirect human, review-level, and mechanistic sources are weighted separately.
• Directional signal is counted within the assigned outcome class only. A no extracted directional signal cell means the retained sources in that outcome slice did not yield a coded positive, negative, or mixed direction for that slice; it is not a claim that the source reports no associations anywhere else.
• Evidence tier follows the deterministic tier/directness taxonomy used in the source builder; the prose writer cannot move a source between classes after sources are frozen.

Load-Bearing Tensions

• Additional corpus sources included animal/preclinical evidence; severity 5 disagreement: Elliott 2017 vs Frohlich 2020; Elliott 2017 reports negative effect on contextual other; Frohlich 2020 reports positive on the same outcome — direct conflict
• Severity 5 disagreement: Elliott 2017 vs Chen 2021; Elliott 2017 reports negative effect on contextual other; Chen 2021 reports positive on the same outcome — direct conflict
• Severity 5 disagreement: Frohlich 2020 vs Dou 2021; Frohlich 2020 reports positive effect on contextual other; Dou 2021 reports negative on the same outcome — direct conflict
• Severity 5 disagreement: Frohlich 2020 vs Sun 2022; Frohlich 2020 reports positive effect on contextual other; Sun 2022 reports negative on the same outcome — direct conflict
• Severity 5 disagreement: Frohlich 2020 vs Frohlich 2022; Frohlich 2020 reports positive effect on contextual other; Frohlich 2022 reports negative on the same outcome — direct conflict
• Severity 5 disagreement: Dou 2021 vs Chen 2021; Dou 2021 reports negative effect on contextual other; Chen 2021 reports positive on the same outcome — direct conflict
• Severity 5 disagreement: Chen 2021 vs Sun 2022; Chen 2021 reports positive effect on contextual other; Sun 2022 reports negative on the same outcome — direct conflict
• Severity 5 disagreement: Chen 2021 vs Frohlich 2022; Chen 2021 reports positive effect on contextual other; Frohlich 2022 reports negative on the same outcome — direct conflict

Conclusion

For Growth differentiation factor 11, the final interpretation is deliberately tiered: the retained clinical and adjacent evidence profile defines a bounded geroscience rationale, but the corpus does not support treating mechanistic target engagement, intermediate biomarkers, and patient-relevant outcomes as interchangeable evidence. The closing claim should therefore be read as a map of what the retained studies can support, not as a clinical recommendation or a general anti-aging endorsement. Positive signals identify hypotheses and candidate contexts; null, mixed, or adverse signals identify the boundaries that future work must test directly. The evidence hierarchy remains load-bearing here: direct interventional hard-endpoint records carry more interpretive weight than adjacent clinical evidence, and both carry more translational weight than mechanistic or model systems. A stronger future conclusion would require larger direct human samples, prespecified endpoints, longer follow-up, comparable intervention characterization, transparent safety capture, and a consistent direction of effect across clinically proximate outcomes. Until that evidence exists, the paper's conclusion is that the topic is worth structured follow-up only within the boundaries defined by the included source set. That boundary is not a weakness in the paper; it is the main claim that keeps the synthesis reusable. Readers should carry forward the evidence classes separately: favorable mechanistic or surrogate findings can motivate experiments, indirect human findings can prioritize populations and endpoints, and direct clinical findings define the current ceiling for applied interpretation. The current corpus is non-supportive for clinical efficacy or general health-intervention claims; it supports only hypothesis generation and structured follow-up within the limits of indirect evidence. Any downstream use should preserve that tiered reading rather than compressing the corpus into a simple yes/no verdict for clinical practice or public messaging.

Methods

Review type and protocol

This manuscript is reported as a Evidence brief. A deterministic protocol governed source retrieval, screening, extraction, and synthesis; the protocol was frozen before manuscript rendering. The full audit trail is in the supplementary methods_pack.json and the timestamped submission directory synthesis-gdf11-v06-DAILY-2026-06-22T04-20-15Z.

Information sources

Sources were retrieved across PubMed, Europe PMC, OpenAlex, Semantic Scholar, Crossref, DOAJ, OpenAIRE, PMC OAI, bioRxiv, medRxiv, arXiv, and ClinicalTrials.gov. Retrieval window: 2026-06-22.

Search strategy

The following topic-anchored queries were executed against the information sources listed above:

• GDF11 AND aging AND human
• growth differentiation factor 11 AND rejuvenation
• GDF11 AND cardiac aging
• GDF11 AND muscle aging controversy
• GDF11 AND myostatin assay

Eligibility criteria

• Sources whose primary content addresses gdf11.
• Sources with extractable quantitative or qualitative findings.
• Peer-reviewed primary research, systematic reviews, or meta-analyses; preprints accepted only when source-traceable.
• Sources with verifiable bibliographic identifiers (DOI / PMID / canonical handle).

Selection of sources of evidence

The synthesis did not begin from an unfiltered database export. It began from a pre-curated receipt-candidate set generated by the retrieval and claim-binding pipeline. Of 188 records in the receipt-candidate union, 68 were classified as source candidates and 48 were admitted as traceable synthesis sources. Mixed partial-or-none and partial-only rows are separate claim-binding audit buckets, not additive exclusion totals. No additional records were excluded after final source admission.

source admission funnel

Admission bucket	n
Receipt candidate union	188
Classified source candidates	68
No extractable claims	52
None-only claim binding	4
Mixed partial-or-none claim-binding candidates	44
Partial-only claim-binding candidates	13
Strict high-confidence sources	7
Admitted final sources	48

Exclusion reasons

• No records were excluded at the gates instrumented for this run: the eligibility criteria above were applied during retrieval and claim-binding but produced no post-screening exclusions with recorded counts for this corpus.

Data items

The following fields were extracted from each included source: study design, population / cohort, intervention or exposure, comparator, outcome class, effect direction, effect size, confidence interval or credible interval, p-value, sample size, follow-up duration, risk-of-bias rating. Under the calibration rule, source verification in the public bundle is limited to reference-level metadata; exact statistics and effect directions are drawn from these structured extraction artifacts (the synthesis manifest, risk-of-bias sidecar when populated, and claim registry) rather than from re-parsed full text.

Risk-of-bias appraisal

Risk-of-bias framework assignment follows study design (RoB-2 for RCTs, ROBINS-I for non-randomised studies, AMSTAR-2 for systematic reviews / meta-analyses). Public appraisal claims are limited to populated risk_of_bias.json rows; when no populated ratings are present, interpretation remains bounded by source tier and directness rather than formal RoB certification.

Synthesis approach

Evidence-tension synthesis: claims grouped by outcome class (cardiometabolic, contextual adjacent evidence, frailty, immune and inflammation, mechanism, mortality and survival, muscle function); within-class agreement, disagreement, and directness gaps surfaced explicitly. Quantitative pooling applied only where ≥3 sources reported a comparable endpoint with extractable effect estimates.

AI-use disclosure

Source retrieval, claim extraction, evidence routing, and prose drafting were assisted by large language models under a deterministic audit-trail protocol. Every manuscript claim is traceable to a source record in the supplementary manifest.json. Final eligibility and interpretation decisions are author-verified.

Accountability

Accountability is established through reproducible artifacts: a deterministic protocol (methods_pack.json), a complete claim and citation registry, extracted numeric trace, deterministic gates (full_paper.journal_surface.json, pre_submit_gate.json, artifact_consistency.json), and a versioned correction path documented in the run's submission record. Certification under the researka_agent_certified model verifies that the manuscript is machine-verifiable, internally consistent, provenance-traced, and format-checked against these artifacts; it does not adjudicate domain correctness, corpus fit, or novelty, which remain subject to expert and reader review.

Additional corpus sources included animal/preclinical evidence; additional corpus sources informed the synthesis without anchoring a foregrounded quantitative claim and are catalogued for completeness: Song 2022, Jin 2019, Kraler 2023, Katsimpardi 2019, Liu 2025, Chen 2026, Zhang 2024, Dai 2020, Suh 2020, Congdon 2025, Hao 2024, Liu 2019, Tanaka 2021, Borsky 2023, Starcher 2021, Ravenscroft 2021, Idkowiak-Baldys 2019, Luo 2019, Wu 2024, Zhang 2017, Spencer 2023, Qi 2020, Gao 2022, Zhang 2022, Strosahl 2024, Lin 2023, Braun 2024, Rochette 2020, Suh 2020b.

References

• Wang 2023. GDF11 slows excitatory neuronal senescence and brain ageing by repressing p21. Nature Communications, 2023. DOI: 10.1038/s41467-023-43292-1. PMID: 37978295.
• Song 2022. Dietary intake of GDF11 delays the onset of several biomarkers of aging in male mice through anti-oxidant system via Smad2/3 pathway. Biogerontology, 2022. DOI: 10.1007/s10522-022-09967-w. PMID: 35604508.
• Walker 2025. Activated GDF11/8 subforms predict cardiovascular events and mortality in humans. Nature Communications, 2025. DOI: 10.1038/s41467-025-61815-w. PMID: 40664633.
• Moigneu 2023. Systemic GDF11 attenuates depression-like phenotype in aged mice via stimulation of neuronal autophagy. Nature Aging, 2023. DOI: 10.1038/s43587-022-00352-3. PMID: 37118117.
• Schon 2023. Acute endurance exercise modulates growth differentiation factor 11 in cerebrospinal fluid of healthy young adults. Frontiers in Endocrinology, 2023. DOI: 10.3389/fendo.2023.1137048. PMID: 37033257.
• Jin 2019. A GDF11/myostatin inhibitor, GDF11 propeptide-Fc, increases skeletal muscle mass and improves muscle strength in dystrophic mdx mice. Skeletal Muscle, 2019. DOI: 10.1186/s13395-019-0197-y. PMID: 31133057.
• Hung 2024. Protogenin facilitates trunk-to-tail HOX code transition via modulating GDF11/SMAD2 signaling in mammalian embryos. Communications Biology, 2024. DOI: 10.1038/s42003-024-07342-8. PMID: 39702818.
• Wang 2021. Loss of Growth Differentiation Factor 11 Shortens Telomere Length by Downregulating Telomerase Activity. Frontiers in Physiology, 2021. DOI: 10.3389/fphys.2021.726345. PMID: 34588995.
• Bajikar 2023. MeCP2 regulates Gdf11 , a dosage-sensitive gene critical for neurological function. eLife, 2023. DOI: 10.7554/eLife.83806. PMID: 36848184.
• Anon-Hidalgo 2019. Circulating GDF11 levels are decreased with age but are unchanged with obesity and type 2 diabetes. Aging (Albany NY), 2019. DOI: 10.18632/aging.101865. PMID: 30897065.
• Guo 2025. GDF11-secreting cell transplant efficiently ameliorates age-related pulmonary fibrosis. Molecular Therapy, 2025. DOI: 10.1016/j.ymthe.2025.07.003. PMID: 40676836.
• Cai 2023. Myogenic differentiation of human myoblasts and Mesenchymal stromal cells under GDF11 on Poly-ɛ-caprolactone-collagen I-Polyethylene-nanofibers. BMC Molecular and Cell Biology, 2023. DOI: 10.1186/s12860-023-00478-1. PMID: 37189080.
• Walker 2020. Exogenous GDF11, but not GDF8, reduces body weight and improves glucose homeostasis in mice. Scientific Reports, 2020. DOI: 10.1038/s41598-020-61443-y. PMID: 32165710.
• Kraler 2023. Circulating GDF11 exacerbates myocardial injury in mice and associates with increased infarct size in humans. Cardiovascular Research, 2023. DOI: 10.1093/cvr/cvad153. PMID: 37742057.
• Katsimpardi 2019. Systemic GDF11 stimulates the secretion of adiponectin and induces a calorie restriction‐like phenotype in aged mice. Aging Cell, 2019. DOI: 10.1111/acel.13038. PMID: 31637864.
• Frohlich 2022. GDF11 inhibits adipogenesis and improves mature adipocytes metabolic function via WNT/β‐catenin and ALK5/SMAD2/3 pathways. Cell Proliferation, 2022. DOI: 10.1111/cpr.13310. PMID: 35920128.
• Liu 2025. GDF11 alleviates glucocorticoid-induced osteonecrosis of the femoral head by regulating angiogenesis via the PI3K-AKT-eNOS pathway. Communications Biology, 2025. DOI: 10.1038/s42003-025-09078-5. PMID: 41291036.
• Frohlich 2020. GDF11 induces mild hepatic fibrosis independent of metabolic health. Aging (Albany NY), 2020. DOI: 10.18632/aging.104182. PMID: 33126224.
• Chen 2021. Growth differentiation factor 11 attenuates cardiac ischemia reperfusion injury via enhancing mitochondrial biogenesis and telomerase activity. Cell Death & Disease, 2021. DOI: 10.1038/s41419-021-03954-8. PMID: 34215721.
• Chen 2026. Elevated circulating GDF11 and its role in age-related sarcopenia: insights from clinical, transcriptomic, and in vitro analyses. Frontiers in Aging, 2026. DOI: 10.3389/fragi.2026.1736069. PMID: 41822302.
• Zhang 2024. GDF11 protects against mitochondrial-dysfunction-dependent NLRP3 inflammasome activation to attenuate osteoarthritis. Journal of Advanced Research, 2024. DOI: 10.1016/j.jare.2024.08.001. PMID: 39103049.
• Lu 2019. Gdf11 gene transfer prevents high fat diet-induced obesity and improves metabolic homeostasis in obese and STZ-induced diabetic mice. Journal of Translational Medicine, 2019. DOI: 10.1186/s12967-019-02166-1. PMID: 31847906.
• Dai 2020. Growth differentiation factor 11 attenuates liver fibrosis via expansion of liver progenitor cells. Gut, 2020. DOI: 10.1136/gutjnl-2019-318812. PMID: 31767630.
• Elliott 2017. Lifelong exercise, but not short‐term high‐intensity interval training, increases GDF 11, a marker of successful aging: a preliminary investigation. Physiological Reports, 2017. DOI: 10.14814/phy2.13343. PMID: 28701523.
• Suh 2020. GDF11 promotes osteogenesis as opposed to MSTN, and follistatin, a MSTN/GDF11 inhibitor, increases muscle mass but weakens bone. Proceedings of the National Academy of Sciences of the United States of America, 2020. DOI: 10.1073/pnas.1916034117. PMID: 32071240.
• Congdon 2025. Investigating and correcting a rare pathogenic mutation in GDF11. Human Genetics and Genomics Advances, 2025. DOI: 10.1016/j.xhgg.2025.100559. PMID: 41414712.
• Hao 2024. Hapln1 promotes dedifferentiation and proliferation of iPSC-derived cardiomyocytes by promoting versican-based GDF11 trapping. Journal of Pharmaceutical Analysis, 2024. DOI: 10.1016/j.jpha.2023.09.013. PMID: 38618242.
• Liu 2019. GDF11 upregulation independently predicts shorter overall-survival of uveal melanoma. PLoS ONE, 2019. DOI: 10.1371/journal.pone.0214073. PMID: 30883611.
• Tanaka 2021. Longitudinal Relationship Between Growth Differentiation Factor 11 and Physical Activity in Chronic Obstructive Pulmonary Disease. International Journal of Chronic Obstructive Pulmonary Disease, 2021. DOI: 10.2147/COPD.S301690. PMID: 33883893.
• Borsky 2023. Evaluation of potential aging biomarkers in healthy individuals: telomerase, AGEs, GDF11/15, sirtuin 1, NAD+, NLRP3, DNA/RNA damage, and klotho. Biogerontology, 2023. DOI: 10.1007/s10522-023-10054-x. PMID: 37523061.
• Starcher 2021. A systems approach using Diversity Outbred mice distinguishes the cardiovascular effects and genetics of circulating GDF11 from those of its homolog, myostatin. G3: Genes|Genomes|Genetics, 2021. DOI: 10.1093/g3journal/jkab293. PMID: 34510201.
• Sun 2022. Growth differentiation factor 11 accelerates liver senescence through the inhibition of autophagy. Aging Cell, 2022. DOI: 10.1111/acel.13532. PMID: 34905649.
• Ravenscroft 2021. Heterozygous loss-of-function variants significantly expand the phenotypes associated with loss of GDF11. Genetics in medicine : official journal of the American College of Medical Genetics, 2021. DOI: 10.1038/s41436-021-01216-8. PMID: 34113007.
• Idkowiak-Baldys 2019. Growth differentiation factor 11 (GDF11) has pronounced effects on skin biology. PLoS ONE, 2019. DOI: 10.1371/journal.pone.0218035. PMID: 31181098.
• Luo 2019. Growth differentiation factor 11 inhibits adipogenic differentiation by activating TGF‐beta/Smad signalling pathway. Cell Proliferation, 2019. DOI: 10.1111/cpr.12631. PMID: 31038259.
• Wu 2024. GDF11 inhibits the malignant progression of hepatocellular carcinoma via regulation of the mTORC1‑autophagy axis. Experimental and Therapeutic Medicine, 2024. DOI: 10.3892/etm.2024.12540. PMID: 38682112.
• Zhang 2017. Role of growth differentiation factor 11 in development, physiology and disease. Oncotarget, 2017. DOI: 10.18632/oncotarget.20258. PMID: 29113418.
• Spencer 2023. Association of a variant upstream of growth differentiation factor 11 ( GDF11 ) on carcass traits in crossbred beef cattle. Translational Animal Science, 2023. DOI: 10.1093/tas/txad029. PMID: 36970312.
• Qi 2020. Endogenous GDF11 regulates odontogenic differentiation of dental pulp stem cells. Journal of Cellular and Molecular Medicine, 2020. DOI: 10.1111/jcmm.15754. PMID: 32845070.
• Dou 2021. PPAR α Targeting GDF11 Inhibits Vascular Endothelial Cell Senescence in an Atherosclerosis Model. Oxidative Medicine and Cellular Longevity, 2021. DOI: 10.1155/2021/2045259. PMID: 33728018.
• Gao 2022. Exosome-transmitted miR-3124-5p promotes cholangiocarcinoma development via targeting GDF11. Frontiers in Oncology, 2022. DOI: 10.3389/fonc.2022.936507. PMID: 35978818.
• Zhang 2022. Bioinformatics network analyses of growth differentiation factor 11. Open Life Sciences, 2022. DOI: 10.1515/biol-2022-0044. PMID: 35582621.
• Strosahl 2024. Novel insights into the pleiotropic health effects of growth differentiation factor 11 gained from genome-wide association studies in population biobanks. BMC Genomics, 2024. DOI: 10.1186/s12864-024-10710-7. PMID: 39237910.
• Lin 2023. GDF11 inhibits adipogenesis of human adipose-derived stromal cells through ALK5/KLF15/β-catenin/PPARγ cascade. Heliyon, 2023. DOI: 10.1016/j.heliyon.2023.e13088. PMID: 36755591.
• Smith 2015. GDF11 Does Not Rescue Aging-Related Pathological Hypertrophy. Circ Res, 2015. DOI: 10.1161/circresaha.115.307527. PMID: 26383970.
• Braun 2024. Expression profiling by high-throughput sequencing reveals GADD45, SMAD7, EGR-1 and HOXA3 activation in Myostatin (MSTN) and GDF11 treated myoblasts. Genetics and Molecular Biology, 2024. DOI: 10.1590/1678-4685-GMB-2023-0304. PMID: 39012095.
• Rochette 2020. Anti-Aging Effects of GDF11 on Skin. International Journal of Molecular Sciences, 2020. DOI: 10.3390/ijms21072598. PMID: 32283613.
• Suh 2020b. Similar sequences but dissimilar biological functions of GDF11 and myostatin. Experimental & Molecular Medicine, 2020. DOI: 10.1038/s12276-020-00516-4. PMID: 33077875.

Background References

Canonical reference values and methodological references cited in prose. Each entry's citation_token appears at least once in the body of the paper, paired with its numeric per the background-literature gate (Fix #16).

• Studenski 2011. Studenski S, Perera S, Patel K, et al. Gait speed and survival in older adults. JAMA. 2011;305(1):50-58. DOI: 10.1001/jama.2010.1923. PMID: 21205966.
• Perera 2006. Perera S, Mody SH, Woodman RC, Studenski SA. Meaningful change and responsiveness in common physical performance measures in older adults. J Am Geriatr Soc. 2006;54(5):743-749. DOI: 10.1111/j.1532-5415.2006.00701.x. PMID: 16696738.
• ADA 2024. American Diabetes Association. Standards of Care in Diabetes. Diabetes Care. 2024;47(Suppl 1). DOI: 10.2337/dc24-S006.
• WHO 2000. World Health Organization. Obesity: Preventing and Managing the Global Epidemic. WHO Technical Report Series 894. 2000. PMID: 11234459.
• Cruz-Jentoft 2019. Cruz-Jentoft AJ, Bahat G, Bauer J, et al. Sarcopenia: revised European consensus on definition and diagnosis. Age Ageing. 2019;48(1):16-31. DOI: 10.1093/ageing/afy169. PMID: 30312372.