DavidPerlmutterMD · 2024-07-22 · David Perlmutter (host), Jack Auty
Looking At Microplastics & Inflammation’s Impact on Brain Health | Jack Auty
30 research-tied claims examined: 1 contradicted 6 overstated 1 context 18 supported 4 unverified
6 Overstated
A New England Journal of Medicine study showed that treatment with a GLP-1 receptor agonist halted the progression of Parkinson's disease over a 3-year period.
"Great study came out about 6 to 8 weeks ago in the New England Journal that showed cessation of progression in Parkinson's. It arrested it dead in its tracks using over a 3-year period with a GLP-1 agonist." (said at 0:13:29)
A phase 2 randomized, double-blind trial published in the New England Journal of Medicine (the LIXIPARK trial, PMID 38598572) evaluated the GLP-1 receptor agonist lixisenatide in 156 patients with early Parkinson's disease. The treatment duration was 12 months (followed by a 2-month washout), not 3 years; the 3-year timeframe was an eligibility criterion requiring participants to have been diagnosed less than 3 years prior to enrollment. At 12 months, motor examination scores (MDS-UPDRS part III) changed by -0.04 points in the lixisenatide group compared with +3.04 points in the placebo group (a modest 3.08-point difference on a 132-point scale). While the study demonstrated significantly less motor disability progression over 1 year, stating that it 'arrested it dead in its tracks... over a 3-year period' overstates both the trial duration and the magnitude of the preliminary phase 2 findings.
Obesity and diabetes significantly increase the ratio of TREM1 to TREM2 receptors in microglia, favoring pro-inflammatory activity.
"really interesting results of the study showed that the functionality of these receptors is hugely influenced by two factors, obesity and diabetes. And in the presence of both of those, obesity and diabetes, a significant overrepresentation of TREM1 in comparison to TREM2, they actually did the ratio of TREM1 to TREM2 which was markedly elevated." (said at 0:17:25)
A clinical study evaluated TREM-1, TREM-2, and the TREM-1/TREM-2 ratio across subjects with obesity and type 2 diabetes compared to controls, finding a significantly elevated TREM-1/TREM-2 ratio. However, these measurements were conducted on peripheral blood samples (monocytes and neutrophils) and tissue biopsies (liver, omental, and subcutaneous fat), not in central nervous system microglia. In addition, the study had a very small cross-sectional sample size (n=27 total across three groups).
- partial: Increased expression of triggering receptor expressed on myeloid cells-1 in the population… (Obesity (Silver Spring, Md.) 2017) · cited 41x in the literature
"mRNA transcripts and protein expression of TREM-1, TREM-2, and TREM-1/TREM-2 ratio were examined in the tissue biopsies (liver, omentum, and subcutaneous fat) and blood samples (neutrophils and monocytes) of subjects with obesity and diabetes (SO + D + ; n = 15), subjects with obesity but not diabetes (SO + D - ; n = 7), and subjects without obesity (BMI < 30) and diabetes (SO - D - ; n = 5). The immunofluorescence and RT-PCR revealed significant increase in TREM-1, decrease in TREM-2, and increase in the TREM1/TREM2 ratio in SO + D + group compared with other groups." (abstract, methods and results, passage verified)
pubmedfull study (doi)
Phase 1 clinical trials have tested drugs designed to kill or deplete microglia to prevent Alzheimer's disease.
"In fact, there have been clinical trials on drugs that kill your microglia. And actually, these are relatively recent, maybe 5 years ago, there have been clinical trials on phase one clinical trials on drugs to kill your microglia in the hope of preventing Alzheimer's disease." (said at 0:14:04)
Pharmacological depletion and ablation of microglia (primarily via colony-stimulating factor 1 receptor [CSF1R] inhibitors such as PLX3397 and PLX5622) has been extensively investigated in preclinical rodent models of Alzheimer's disease. However, no Phase 1 clinical trials have tested microglial depletion or killing strategies in humans to prevent Alzheimer's disease; human trials targeting microglia focus on immune modulation (such as TREM2 agonism) rather than cell ablation.
An economic analysis of the FINGER trial demonstrated cost savings for the government through reductions in falls, heart attacks, and prescriptions for antidepressants and cardiovascular treatments.
"They did an economic study on these people that were in the FINGER trial, which was done in Finland... then once they did the economic study of it, they found that they saved the government money because there were fewer falls, there were fewer heart attacks, there were fewer prescriptions for antidepressants, fewer prescriptions for cardiovascular interventions." (said at 0:48:40)
Health economic modeling of the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) demonstrated potential cost savings and quality-adjusted life year (QALY) gains. However, these savings were derived from a lifetime Markov decision model simulating cognitive health states and avoided dementia cases, rather than an empirical demonstration of government budget savings driven by measured reductions in falls, myocardial infarctions, or specific prescriptions for antidepressants and cardiovascular medications.
- partial: Dementia prevention: The potential long‐term cost‐effectiveness of the FINGER prevention p… (Alzheimer s & Dementia 2022) · cited 62x in the literature
"A life-time Markov model with societal perspective, simulating a cohort of people at risk of dementia reflecting usual care and the FINGER program... Costs were 1,653,275 and 1,635,346 SEK and quality-adjusted life years (QALYs) were 8.636 and 8.679 for usual care and the FINGER program, respectively, resulting in savings of 16,928 SEK (2023 US$) and 0.043 QALY gains per person, supporting extended dominance for the FINGER program. A total of 1623 dementia cases were avoided with 0.17 fewer person-years living with dementia." (abstract, results)
openalexfull study (doi)
A study comparing ping pong to walking (10,000 steps) found that playing ping pong led to greater improvements in cortical thickness and cognitive performance.
"That actually reminds me of a study where they compared walking, I think it was 10,000 steps, versus ping pong. And they actually found they measured cortical thickness and they measured cognitive performance. They found that the ping pong was better than the walking." (said at 0:50:14)
No published study was located comparing table tennis to walking (or 10,000 steps) that measured cortical thickness; this does not prove such a study does not exist. The most relevant published randomized trial (PMID 28959200) compared 6 months of open-skill exercise (table tennis, n = 21) against closed-skill aerobic exercise (brisk walking/jogging or cycling, n = 22) and controls (n = 21) in older adults. That study measured electrophysiology (event-related potential P3 amplitudes over frontal and parietal scalp regions) rather than structural MRI cortical thickness. Furthermore, cognitive findings were mixed rather than uniformly favoring table tennis: while table tennis led to greater reaction time improvements during task-switching, the walking/cycling group showed superior improvements in working memory accuracy (2-back task), and both groups demonstrated similar increases in cortical P3 amplitudes.
Histological examinations of shearwater birds that ingested plastic revealed widespread organ fibrosis in the liver, kidneys, and stomach, a pathology termed 'plasticosis'.
"We've done histology now and we've shown fibrosis all throughout the liver, the kidneys, the stomach. And we've actually defined this as a new disease. We feel like it deserves a word that we can attach to it and it's called plasticosis." (said at 0:54:26)
In the landmark 2023 study that introduced and defined 'Plasticosis' (Charlton-Howard et al.), histological examinations using Masson's trichrome staining were conducted on the proventriculus (stomach) of Flesh-footed Shearwater fledglings, finding widespread plastic-associated fibrosis and scarring within the mucosa and submucosa. However, the published histological proof of fibrosis was specific to the stomach tissue; broader systemic effects on the liver and kidneys have primarily been demonstrated through blood proteomic signatures indicating multi-organ dysfunction and compromised organ secretion, rather than published histological demonstration of fibrosis throughout the liver and kidneys.
- partial: 'Plasticosis': Characterising macro- and microplastic-associated fibrosis in seabird tissu… (Journal of hazardous materials 2023) · cited 201x in the literature
"A Masson's Trichrome stain was used to document any evidence of plastic-induced fibrosis, using collagen as a marker for scar tissue formation in the proventriculus (stomach) of 30 Flesh-footed Shearwater fledglings from Lord Howe Island, Australia. Plastic presence was highly associated with widespread scar tissue formation and extensive changes to, and even loss of, tissue structure within the mucosa and submucosa... Further, the extent and severity of fibrosis documented in this study gives support for a novel, plastic-induced fibrotic disease, which we define as 'Plasticosis,'." (abstract, results, passage verified)
pubmedfull study (doi) - context: Seabirds in crisis: Plastic ingestion induces proteomic signatures of multiorgan failure a… (Science advances 2025) · cited 34x in the literature
"Secreted proteins were less abundant, indicating that the stomach, liver, and kidneys are not functioning as normal. Alarmingly, these signatures included evidence of neurodegeneration in <90-day-old seabird chicks with high levels of ingested plastic." (abstract, results, passage verified)
pubmedfull study (doi)
Unverified means no publication matching the claim was located; it does not prove the claim false. Spotted an error? See the corrections policy - disputes from the people quoted are prioritized.