AUTHOR=Wang Fei , Qin Yaqin , Li Zongyou 

TITLE=Serum retinol-binding protein 4 in stroke patients: correlation with T helper 17/regulatory T cell imbalance and 3-year cognitive function decline

JOURNAL=Frontiers in Neurology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2023.1217979

DOI=10.3389/fneur.2023.1217979

ISSN=1664-2295

ABSTRACT=<sec id="sec1"><title>Objective</title><p>Retinol-binding protein 4 (RBP4) promotes atherosclerotic progression and neuronal loss, whereas its association with cognitive impairment in stroke is unclear. Hence, this prospective study aimed to explore the association of serum RBP4 with the T helper (Th)17/regulatory T (Treg) cell ratio and its correlation with cognitive impairment in stroke patients.</p></sec><sec id="sec2"><title>Methods</title><p>Peripheral blood samples from 265 stroke patients and 50 healthy controls (HCs) were collected at enrollment for serum RBP4 (by enzyme-linked immunosorbent assay) and Th17 and Treg cells (by flow cytometry) determination. Additionally, stroke patients underwent routine follow-ups, and their Mini-Mental State Examination (MMSE) scores were assessed at baseline and in years 1, 2, and 3 after enrollment.</p></sec><sec id="sec3"><title>Results</title><p>Serum RBP4 was elevated in stroke patients compared to HCs (<italic>p</italic> &lt; 0.001), with a good ability to differentiate stroke patients from HCs (area under the curve: 0.815). Serum RBP4 was positively associated with Th17 cells (<italic>p</italic> &lt; 0.001) and the Th17/Treg cell ratio (<italic>p</italic> &lt; 0.001) and negatively associated with Treg cells (<italic>p</italic> = 0.003) in stroke patients, whereas it was only positively associated with the Th17/Treg cell ratio (<italic>p</italic> = 0.027) but not with Th17 (<italic>p</italic> = 0.075) or Treg (<italic>p</italic> = 0.130) cells in HCs. Furthermore, increased serum RBP4 was associated with a lower MMSE score (<italic>p</italic> &lt; 0.001) and a lower incidence of cognition impairment (<italic>p</italic> = 0.005) at enrollment in stroke patients, as were Th17 cells and the Th17/Treg cell ratio (all <italic>p</italic> &lt; 0.050). The 1-, 2-, and 3-year MMSE scores in stroke patients were 25.9 ± 2.0, 25.3 ± 2.3, and 24.9 ± 2.3, respectively. More importantly, serum RBP4 was negatively correlated with 1-, 2-, and 3-year MMSE scores (all <italic>p</italic> &lt; 0.001) and positively associated with 1-year (<italic>p</italic> = 0.013), 2-year (<italic>p</italic> = 0.007), and 3-year (<italic>p</italic> = 0.001) MMSE score declines in stroke patients.</p></sec><sec id="sec4"><title>Conclusion</title><p>Serum RBP4 is positively associated with a Th17/Treg cell imbalance and, more importantly, it is indicative of cognitive function decline within 3 years in stroke patients. Thus, early and timely interventions and physical rehabilitation are more necessary in stroke patients with high serum RBP4.</p></sec>