Role of the blood-brain barrier in the evolution of feeding and cognition.
Level 5 - mechanism / opinion, no new human data
Narrative review and theoretical mechanism paper without primary clinical or empirical human trial data.
PubMed 22612379 · doi:10.1111/j.1749-6632.2012.06568.x
What was done
The author synthesizes mechanistic and evolutionary hypotheses regarding how the blood-brain barrier (BBB) controls the transport of metabolic and gastrointestinal hormones (such as leptin, insulin, and ghrelin) to influence both nutritional homeostasis and cognitive processes.
What was found
The abstract reports no experimental numbers or statistical analyses. It describes mechanistic relationships: impaired transport of leptin across the BBB contributes to obesity; elevated triglycerides inhibit leptin transport across the BBB (hypothesized as an evolutionary adaptation during starvation to suppress satiety signaling); and the transport of feeding-related peptides across the BBB may mediate effects on neurogenesis, neuroprotection, and cognition.
Why it matters
It provides an evolutionary and mechanistic framework linking peripheral metabolic markers, such as triglycerides, to central appetite control and cognitive function via BBB transport modulation.
Limits
The abstract describes a conceptual review and mechanism-based hypothesis rather than presenting original experimental data, sample sizes, or quantitative metrics. Specific causal claims rely on theoretical extrapolations of animal or in vitro physiological pathways without clinical validation provided in the text.
Cited by
- context Blood-brain barrier leakage in hypothalamic regions controlling feeding can trigger obesity rather than obesity causing the leakage.