Galectin-3 mediated risk of inflammation in stable schizophrenia, with only possible secondary consequences for cognition

Relationships between schizophrenia and the alarmins interleukin-33 (IL-33), soluble receptor of interleukin-33 (sST2) and the ratio IL-33/sST2. A systematic review

Schizophrenia is a multi-aetiologic disease. Inflammation have recently been involved in its pathophysiology. Recent research suggests that inflammation may be a key factor in its pathophysiology. Alarmins, interleukin-33 (IL-33), its soluble receptor sST2 and the ratio IL-33/sST2, have been investigated as neuroinflammation biomarkers. However, data on alarmins in schizophrenia remain scarce and conflicting, with findings varying across studies. The aim of this systematic review consists of analysing the relationships between IL-33, its sST2 and the ratio IL-33/sST2 in schizophrenia. The authors follow the PRISMA recommendations. The keywords IL-33 OR interleukin-33 OR sST2 OR soluble ST2 OR IL-33/sST2 were intersected with the Boolean operator AND with the key words schizophrenia OR psychosis OR psychotic disorder. The search was carried out in PubMed/MEDLINE, EMBASE, PsycInfo, Scopus and Web of Science. Despite the initial search yielding 115 publications, only five studies met inclusion criteria, comprising 107 healthy controls (HC) and 267 patients, highlighting the limited data available. IL-33 and its sST2 were significantly increased in patients with an acute relapse compared to HC, while patients in clinical remission had levels comparable to those of HC. No consistent relationship was found between antipsychotic treatment and IL-33 or sST2 levels, raising questions about the influence of medication on these markers. The quality of evidence was low to moderate (10 ± 1, with an evidence level of 3 ± 0, according to the Oxford Centre for Evidence-Based Medicine criteria). This systematic review highlights the possibility that IL-33 and sST2 play a role in the pathophysiology of schizophrenia, particularly in relation to neuroinflammation and neuronal dysfunction. However, the controversial and inconsistent findings suggest the need for larger, well-controlled studies. Additionally, the lack of mechanistic insight into how these alarmins contribute to schizophrenia pathophysiology remains a critical gap. Understanding the impact of IL-33 and sST2 on neuroinflammatory pathways could provide new therapeutic targets. Future research should also explore whether these markers can aid in early diagnosis or monitoring treatment response.

Tannic acid coated nanosuspension for oral delivery of chrysin intended for anti-schizophrenic effect in mice

Chrysin is a flavonoid drug with numerous therapeutic activities. It suffers from low intestinal absorption owing to its hydrophobicity. Therefore, the aim of this study is to exploit the efficient technique of nanosuspension (NSP) to formulate chrysin-NSP coated with tannic acid (TA) to improve the solubility and anti-schizophrenic activity of chrysin. A 23 full factorial design was constructed where the independent factors were type of polymer, surfactant concentration (0.5 or 1 %) and the aqueous phase volume (5 or 15 mL), while the dependent responses were the particle size (PS) of the obtained formulation as well as the % chrysin dissolved after 2 h (Q2h). The optimum formulation (NSP-4) composed of 1 % PEG 400 and 1 % Cremophor RH40 in 15 mL aqueous phase. It achieved a PS and Q2h values of 108.00 nm and 38.77 %, respectively. NSP-4 was then coated with TA (TA-coated NSP-4) for further enhancement of chrysin solubility. TA-coated NSP-4 revealed PS and zeta potential values of 150 ± 14 nm and -32.54 ± 2.45 mV, respectively. After 6 h, chrysin dissolved % were 53.97 and 80.22 for uncoated NSP-4 and TA-coated NSP-4, respectively, compared with only 9.47 for free chrysin. The developed formulations and free chrysin were assessed regarding their effect on schizophrenia induced in mice by cuprizone (CPZ). Treatment with the developed formulations and free chrysin ameliorated demyelination and behavioral deficit induced by CPZ via elevating MBP and PI3K/PKC activities as well as reducing GFAP expression levels. The developed formulations and free chrysin inhibited Galactin-3 and TGF-β expressions and stimulated GST antioxidant enzyme. Furthermore, they maintained the balances in glutamatergic and dopaminergic neurotransmission via modulation on neuregulin-1 and alleviated nuclear pyknosis and degeneration in the neurons. The order of activity was: TA-coated NSP-4 > NSP-4 > free chrysin.