Isoquercitrin Played a Neuroprotective Role in Rats After Cerebral Ischemia/Reperfusion Through Up-Regulating Neuroglobin and Anti-Oxidative Stress

Preparation of PEG-modified isoquercitrin liposomes and anti-chronic kidney disease research

The clinical application of Isoquercitrin (IQ) is limited by its low water solubility and short retention time in the body, despite its diverse pharmacological effects. To address these issues, we prepared polyethylene glycol (PEG)-modified IQ liposomes (IQ-L) using the thin film dispersion method and optimized the formulation through a combination of One Factor at a Time (OFAT) method and response surface experiments. Characterization of the IQ-L that was prepared using the optimal formulation revealed a particle size of 185.48 nm, a polydispersity index of 0.252, a zeta potential of -33.88 mV, and an impressive encapsulation efficiency of 97.84%. In vitro release studies showed a significantly higher cumulative release rate for IQ-L compared to free IQ. Pharmacokinetic evaluations in rats demonstrated a 4.54-fold increase in the area under the concentration-time curve, a 1.63-fold prolongation of the half-life, and a 2.07-fold increase in peak concentration for IQ-L compared to unmodified IQ. Moreover, assessments of renal function in a mouse model indicated promising therapeutic effects. In summary, the PEG-modified liposome system greatly improved the solubility and in vivo retention time of IQ, thus making it a potential clinical agent for the treatment of chronic kidney disease (CKD).

Ameliorative Effects of Raisin Polyphenol Extract on Oxidative Stress and Aging In Vitro and In Vivo via Regulation of Sirt1-Nrf2 Signaling Pathway

Raisins are an important source of polyphenolic compounds in plant foods, and polyphenols are associated with antioxidant and anti-aging activity. In this work, 628 polyphenols in raisin extracts were characterized using UPLC-MS/MS, mainly including tricetin 3'-glucuronide, diisobutyl phthalate, butyl isobutyl phthalate, isoquercitrin and 6-hydroxykaempferol-7-O-glucoside. The oxidative stress in H2O2-induced HepG2 cells and D-gal-induced aging mice was alleviated by raisin polyphenols (RPs) via increases in the cellular levels of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH), along with decreases in malonaldehyde (MDA), reactive oxygen species (ROS) and advanced glycosylation end-products (AGEs) levels. In addition, it was observed that RPs enhanced Sirt1 and Sirt3 expression, initiating the Keap1-Nrf2 signaling pathway, by upregulating the levels of nuclear Nrf2, facilitating the expressions of the antioxidant proteins NQO1 and HO-1, and downregulating Keap1 and cytoplasmic Nrf2 protein levels in H2O2-induced HepG2 cells and D-gal-induced aging mice. In summary, RP exerted antioxidant and anti-aging effects via regulating the Sirt1-Nrf2 signaling pathway in vitro and in vivo.

Isoquercitrin alleviates OGD/R-induced oxidative stress and impaired mitochondrial biogenesis in SH-SY5Y cells via the NRF1/TFAM pathway

Isoquercitrin (ISO) is a traditional Chinese medicine extract, that has been found to possess potent neuroprotective properties. However, its precise role in the context of ischemic stroke (IS) remains to be fully elucidated. We constructed an in vitro model of IS induced by OGD/R in SH-SY5Y cells. Cell viability, the levels of oxidative stress-related indicators (8-OHDG, MDA, SOD, GSH, and GSH-Px), ROS, and mitochondrial membrane potential were measured by using detection kits. The protein levels of GPX1, SOD, Cytc were measured. The mRNA levels of mitochondrial biogenesis-related indicators (Cytb, CO1, ND2, ND5, and ND6), and mtDNA copy number were measured by RT-qPCR. ATP levels were measured. Molecular docking between ISO and NRF1, and Co-IP assay for NRF1 and TFAM interaction were performed. Expression of NRF1 and TFAM was evaluated. ISO treatment reversed the detrimental effects of OGD/R on cell viability, attenuated the elevation of oxidative stress markers, restored antioxidant levels, and alleviated the impairment of mitochondrial biogenesis in SH-SY5Y cells. ISO interacted with NRF1 and increased its expression along with TFAM. Silencing NRF1 reversed the protective effects of ISO, suggesting its involvement in mediating the neuroprotective effects of ISO. ISO alleviates oxidative stress and mitochondrial biogenesis damage induced by OGD/R in SH-SY5Y cells by upregulating the NRF1/TFAM pathway.

Protective Effect of Ramipril Against Oxidant and Proinflammatory Cytokine Damage Induced by Ischemia-Reperfusion in Ovarian Tissue in Rats

BACKGROUND

It is known that the increase in oxidants and proinflammatory cytokines, as well as the decrease in antioxidants, play a role in ovarian ischemia-reperfusion (I/R) injury. The antioxidant and anti-inflammatory properties of ramipril have been studied in various diseases. This study aims to investigate the effect of ramipril on I/R-induced ovarian damage in rats.

METHODS

Rats were divided into healthy (HG), sham (SG), ovary I/R (OIR), and ramipril + ovary I/R (ROIR) groups (n = 6/each group). One hour before the surgical procedures, ROIR was given 2 mg/kg ramipril. The lower abdomen of the SG, OIR, and ROIR was surgically opened. Right ovarian tissues of OIR and ROIR were subjected to 2 hours of ischemia and 6 hours of reperfusion. Then, all animals were euthanized, and their right ovaries were removed. Ovarian tissues were examined for oxidants (malondialdehyde), antioxidants (total glutathione, superoxide dismutase, and catalase), and proinflammatory cytokines (nuclear factor kappa-B, tumor necrosis factor-alpha, interleukin 1 beta, and interleukin-6) analysis was performed. Tissues were examined histopathologically.

RESULTS

The ovarian tissue of the OIR, which underwent the I/R procedure, exhibited a significant increase in oxidant and proinflammatory cytokine levels, along with a decrease in antioxidant levels (P < .001). Ramipril suppressed the I/R-induced increase in oxidants and pro-inflammatory cytokines and the decrease in antioxidants (P < .001). Ramipril also attenuated I/R-induced histopathological damage in ovarian tissue (P < .05).

CONCLUSION

Ramipril treatment may be a treatment strategy to protect ovarian tissue against oxidative and inflammatory damage of I/R.

Xanthohumol attenuates renal ischemia/reperfusion injury by inhibiting ferroptosis

Ischemia/reperfusion injury (IRI) is a notable contributor to kidney injury, but effective prevention and treatment options are limited. The present study aimed to evaluate the impact of xanthohumol (XN), a kind of flavonoid, on renal IRI and its pathological process in rats. Rats and HK-2 cells were divided into five groups: Sham (control), IR [hypoxia-reoxygenation (HR)], IR (HR) + XN, IR (HR) + erastin or IR (HR) + XN + erastin. The effects of XN and erastin (a ferroptosis inducer) on IRI in rats were evaluated using blood urea nitrogen, plasma creatinine, glutathione, superoxide dismutase and malondialdehyde kits, western blotting, cell viability assay, hematoxylin and eosin staining and reactive oxygen species (ROS) detection. Nrf2 small interfering (si)RNA was used to investigate the role of the Nrf2/heme oxygenase (HO)-1 axis in XN-mediated protection against HR injury. Cell viability, ROS levels and expression of ferroptosis-related proteins were analyzed. Following IR, renal function of rats was severely impaired and oxidative stress and ferroptosis levels significantly increased. However, XN treatment decreased renal injury and inhibited oxidative stress and ferroptosis in renal tubular epithelial cells. Additionally, XN upregulated the Nrf2/HO-1 signaling pathway and Nrf2-siRNA reversed the renoprotective effect of XN. XN effectively decreased renal IRI by inhibiting ferroptosis and oxidative stress and its protective mechanism may be associated with the Nrf2/HO-1 signaling pathway.