Objective The purpose of this study was to investigate the mechanism of action of polypeptide extracts of Eupolyphaga sinensis Walker ( ESW) against oxidative aging.Methods Mice were intraperitoneally injected D-galac-tose for consecutive 20 days to establish an aging mouse model.The model mice were administered with different doses of ESW polypeptide (0, 40, 80, 160 mg/kg/d).The normal activity, movement and anti-stress ability of the mice were ob-served.The activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX) in blood and different tissues and the content of glutathione ( GSH) and malondialdehyde ( MDA) of the aging mice were assessed by xanthin oxidase activity measurement and spectrophotometry, respectively.The expression of nuclear factor erythroid 2-re-lated factor 2 (Nrf2) in Caco-2 cells was detected by immunofluorescence.Results Comparing the control and polypep-tide groups, there were significant decreases of body weight gain, organ indexes, anti-stress ability and activity capacity, the activity of SOD, CAT, GSH-PX and the content of GSH, and an increase of the content of MDA in blood and different tissues in the aging mice.With the increasing dose of polypeptide extracts of ESW, the body weight gain, organ indexes of the liver, spleen and kidney were significantly increased, the static and dynamic exercise time was prolonged in the poly-peptide group, and their abilities of hypoxia tolerance and heat tolerance were close to that of normal controls.The SOD, CAT, GSH-PX activity and GSH level in blood and different tissues were significantly increased, but MDA content de-creased.The expression of Nrf2 in Caco-2 cell nuclei was significantly increased in the polypeptide group, close to that of the positive control group.Conclusions The results of our study show that polypeptide extracts of ESW improve the anti-stress and antioxidative capacity in D-galactose-induced mouse models of oxidative aging by initiating Nrf2-ARE antioxidant signaling pathway, therefore, delay the oxidative aging in mice.

Background/Aims: The occurrence and development of hepatitis B virus-associated acute-onchronic liver failure (HBV-ACLF) is closely related to the immune pathway. We explored the heterogeneity of peripheral blood T cell subsets and the characteristics of exhausted T lymphocytes, in an attempt to identify potential therapeutic target molecules for immune dysfunction in ACLF patients. Methods: A total of 83,577 T cells from HBV-ACLF patients and healthy controls were screened for heterogeneity by single-cell RNA sequencing. In addition, exhausted T-lymphocyte subsets were screened to analyze their gene expression profiles, and their developmental trajectories were investigated. Subsequently, the expression of exhausted T cells and their capacity in secreting cytokines (interleukin 2, interferon γ, and tumor necrosis factor α) were validated by flow cytometry. Results: A total of eight stable clusters were identified, among which CD4 + TIGIT + subset and CD8 + LAG-3 + subset, with high expression of exhaust genes, were significantly higher in the HBV-ACLF patients than in normal controls. As shown by pseudotime analysis, T cells experienced a transition from naïve T cells to effector T cells and then exhausted T cells. Flow cytometry confirmed that the CD4 + TIGIT + subset and CD8 + LAG-3 + subset in the peripheral blood of the ACLF patients were significantly higher than those in the healthy controls. Moreover, in vitro cultured CD8 + LAG-3 + T cells were significantly fewer capable of secreting cytokines than CD8 + LAG-3- subset. Conclusions Peripheral blood T cells are heterogeneous in HBV-ACLF. The exhausted T cells markedly increase during the pathogenesis of ACLF, suggesting that T-cell exhaustion is involved in the immune dysfunction of HBV-ACLF patients.

This study was designed to investigate the potential protective effect of isopimpinelline against para-chlorophenylalanine(PCPA)-induced pineal gland damage in rats.Forty male Sprague-Dawley(SD)rats were divided into four groups(n=10 each):a normal group,a model group,a melatonin-treated group(10 mg/kg),and an isopimpinelline-treated group(1.5 mg/kg).All groups,except for the normal,received intraperitoneal injection of PCPA(450 mg/kg)to induce pineal gland damage.Subsequent treatments were administered orally for 7 days.Sleep latency and duration were evaluated on the sixth day using the pentobarbital sodium sleep synergy test.After the treatment period,serum melatonin levels and pineal gland inflammation markers were assessed alongside oxidative and antioxidative parameters.Histological examinations of the pineal gland were conducted,and the expression of proteins related to the Nrf2 and NF-κB signaling pathways were quantified.Data showed that isopimpinelline alleviates the structural damage in the pineal gland of model rats,significantly elevated serum melatonin levels,and markedly improved sleep latency and duration(P＜0.05).Isopimpinelline activated the Nrf2 signaling pathway by inhibiting Keap1 expression,which facilitated the nuclear translocation of Nrf2 and upregulated the antioxidant proteins NQO1 and HO-1,thereby mitigating oxidative stress in the pineal gland(P＜0.05).Furthermore,isopimpinelline significantly reduced the levels of pro-inflammatory cytokines IL-2,TNF-α and IL-6.Isopimpinelline also suppressed the NF-κB signaling pathway,reducing the expression of NF-κB p65,IKKβ,and p-IKKβ proteins,as well as the nuclear translocation of NF-κB p65(P＜0.05),thereby providing anti-inflammatory benefits.In conclusion,isopimpinelline could protect pineal gland from damage by activating the Nrf2 signaling pathway and inhibiting the NF-κB pathway.

ObjectiveTo investigate the effect of linalool against acute liver injury induced by aflatoxin B₁（AFB₁） in rats and explore its protective mechanism. MethodTwenty male SPF SD rats were randomly divided into three groups： Control （n=6）， AFB₁ （n=7）， and linalool （n=7） groups. Linalool solution （200 mg·kg^-1） was administered preventatively for 14 days， while the control and AFB₁ groups intragastrically received an equivalent volume of double distilled water. After preventative administration of linalool， AFB₁ solution （1 mg·kg^-1， dissolved in saline） was intraperitoneally injected for two consecutive days to induce acute liver injury in rats. Samples were collected and processed 14 days after model establishment. Pathological changes in liver tissue of rats were observed using Hematoxylin-eosin（HE） staining and Masson staining. Biochemical detection was performed to measure the levels of alanine transaminase（ALT）， aspartate transaminase（AST）， γ-glutamyl transferase（GGT）， lactate dehydrogenase（LDH）， alkaline phosphatase（ALP）， total bilirubin（TBil）， direct bilirubin（DBil）， indirect bilirubin（IBil）， malondialdehyde（MDA）， superoxidedismutase（SOD）， catalase（CAT） ， glutathione（GSH）， Fe³⁺， and Fe²⁺ in the liver tissue. Western blot was adopted to assess protein expression levels of nuclear factor-erythroid 2-related factor 2（Nrf2） and heme oxygenase-1（HO-1）. Molecular docking was performed to verify the binding between linalool and key proteins of the Nrf2/HO-1 signaling pathway. Molecular dynamics techniques were used to confirm the stability and affinity of linalool binding with key proteins of the Nrf2/HO-1 signaling pathway. ResultPathological results showed that compared to that in the AFB₁ group， the liver structure in the linalool group tended to be normal， with a significant decrease in blue collagen fibers. The linalool group exhibited significantly reduced levels of ALT， AST， GGT， LDH， ALP， TBil， DBil， and IBil （P<0.01）， Fe³⁺ and Fe²⁺ content， and oxidative stress marker MDA （P<0.01）. The levels of antioxidants SOD， CAT， and GSH significantly increased （P<0.01）. Molecular docking showed a molecular docking energy between linalool and Nrf2 and HO-1 targets of -5.495 6 and -5.199 4 kcal·mol^-1（1 cal≈4.186 J）， respectively. Molecular dynamics results indicated strong affinity in the binding of linalool with Nrf2 and HO-1. Western blot revealed a significant increase in Nrf2 protein expression （P<0.05） and a decrease in HO-1 protein expression （P<0.01） in the linalool group. ConclusionLinalool may protect against AFB₁-induced acute liver injury by modulating the Nrf2/HO-1 ferroptosis signaling pathway to inhibit liver cell ferroptosis and regulate hepatic oxidative stress levels.