The Interplay between Mitochondrial Dysfunction and Ferroptosis during Ischemia-Associated Central Nervous System Diseases.

Cerebral ischemia, a leading cause of disability and mortality worldwide, triggers a cascade of molecular and cellular pathologies linked to several central nervous system (CNS) disorders. These disorders primarily encompass ischemic stroke, Alzheimer's disease (AD), Parkinson's disease (PD), epilepsy, and other CNS conditions. Despite substantial progress in understanding and treating the underlying pathological processes in various neurological diseases, there is still a notable absence of effective therapeutic approaches aimed specifically at mitigating the damage caused by these illnesses. Remarkably, ischemia causes severe damage to cells in ischemia-associated CNS diseases. Cerebral ischemia initiates oxygen and glucose deprivation, which subsequently promotes mitochondrial dysfunction, including mitochondrial permeability transition pore (MPTP) opening, mitophagy dysfunction, and excessive mitochondrial fission, triggering various forms of cell death such as autophagy, apoptosis, as well as ferroptosis. Ferroptosis, a novel type of regulated cell death (RCD), is characterized by iron-dependent accumulation of lethal reactive oxygen species (ROS) and lipid peroxidation. Mitochondrial dysfunction and ferroptosis both play critical roles in the pathogenic progression of ischemia-associated CNS diseases. In recent years, growing evidence has indicated that mitochondrial dysfunction interplays with ferroptosis to aggravate cerebral ischemia injury. However, the potential connections between mitochondrial dysfunction and ferroptosis in cerebral ischemia have not yet been clarified. Thus, we analyzed the underlying mechanism between mitochondrial dysfunction and ferroptosis in ischemia-associated CNS diseases. We also discovered that GSH depletion and GPX4 inactivation cause lipoxygenase activation and calcium influx following cerebral ischemia injury, resulting in MPTP opening and mitochondrial dysfunction. Additionally, dysfunction in mitochondrial electron transport and an imbalanced fusion-to-fission ratio can lead to the accumulation of ROS and iron overload, which further contribute to the occurrence of ferroptosis. This creates a vicious cycle that continuously worsens cerebral ischemia injury. In this study, our focus is on exploring the interplay between mitochondrial dysfunction and ferroptosis, which may offer new insights into potential therapeutic approaches for the treatment of ischemia-associated CNS diseases.

[Effect on Danggui Shaoyao Powder on mitophagy in rat model of Alzheimer's disease based on PINK1-Parkin pathway].

This study investigated the mechanism of Danggui Shaoyao Powder(DSP) against mitophagy in rat model of Alzheimer's disease(AD) induced by streptozotocin(STZ) based on PTEN induced putative kinase 1(PINK1)-Parkin signaling pathway. The AD rat model was established by injecting STZ into the lateral ventricle, and the rats were divided into normal group, model group, DSP low-dose group(12 g·kg~(-1)·d~(-1)), DSP medium-dose group(24 g·kg~(-1)·d~(-1)), and DSP high-dose group(36 g·kg~(-1)·d~(-1)). Morris water maze test was used to detect the learning and memory function of the rats, and transmission electron microscopy and immunofluorescence were employed to detect mitophagy. The protein expression levels of PINK1, Parkin, LC3BⅠ/LC3BⅡ, and p62 were assayed by Western blot. Compared with the normal group, the model group showed a significant decrease in the learning and memory function(P<0.01), reduced protein expression of PINK1 and Parkin(P<0.05), increased protein expression of LC3BⅠ/LC3BⅡ and p62(P<0.05), and decreased occurrence of mitophagy(P<0.01). Compared with the model group, the DSP medium-and high-dose groups notably improved the learning and memory ability of AD rats, which mainly manifested as shortened escape latency, leng-thened time in target quadrants and elevated number of crossing the platform(P<0.05 or P<0.01), remarkably activated mitophagy(P<0.05), up-regulated the protein expression of PINK1 and Parkin, and down-regulated the protein expression of LC3BⅠ/LC3BⅡ and p62(P<0.05 or P<0.01). These results demonstrated that DSP might promote mitophagy mediated by PINK1-Parkin pathway to remove damaged mitochondria and improve mitochondrial function, thereby exerting a neuroprotective effect.

[Baicalin inhibits LPS/IFN-γ-induced inflammation via TREM2/TLR4/NF-κB pathway in BV2 cells].

This study investigated the mechanism of baicalin on lipopolysaccharide(LPS)/interferon γ(IFN-γ)-induced inflammatory microglia based on the triggering receptor expressed on myeloid cells 2(TREM2)/Toll-like receptor 4(TLR4)/nuclear factor kappaB(NF-κB) pathway. Specifically, LPS and IFN-γ were used to induce inflammation in mouse microglia BV2 cells. Then the normal group, model group, low-dose(5 µmol·L~(-1)) baicalin group, medium-dose(10 µmol·L~(-1)) baicalin group, high-dose(20 µmol·L~(-1)) baicalin group, and minocycline(10 µmol·L~(-1)) group were designed. Cell viability was detected by CCK-8 assay and cell morphology was observed under bright field. The expression of interleukin-1ß(IL-1ß), interleukin-4(IL-4), inducible nitric oxide synthase(iNOS), interleukin-6(IL-6), interleukin-10(IL-10), and arginase-1(Arg-1) mRNA was detected by real-time quantitative PCR, the protein expression of tumor necrosis factor-α(TNF-α), IL-1ß, TREM2, TLR4, inhibitor kappaB-alpha(IκBα), p-IκBα, NF-κB p65 and p-NF-κB p65 by Western blot, and transfer of NF-κB p65 from cytoplasm to nucleus by cellular immunofluorescence. Compared with the normal group, most of the BV2 cells in the model group tended to demonstrate the pro-inflammatory M1 amoeba morphology, and the model group showed significant increase in the mRNA levels of IL-1ß, IL-6, and iNOS, decrease in the mRNA levels of IL-4, IL-10, and Arg-1(P<0.01), rise of the protein expression of TNF-α, IL-1ß, TLR4, p-IκBα, and p-NF-κB p65(P<0.01), reduction in TREM2 protein expression, and increase in the expression of NF-κB p65 in nucleus. Compared with the model group, baicalin groups and minocycline group showed the recovery of BV2 cell morphology, significant decrease in the mRNA levels of IL-1ß, IL-6 and iNOS, increase in the mRNA levels of IL-4, IL-10, and Arg-1(P<0.01), reduction in the protein expression of TNF-α, IL-1ß, TLR4, p-IκBα, and p-NF-κB p65(P<0.05), rise of TREM2 protein expression, and decrease in the expression of NF-κB p65 in nucleus. In summary, these results suggest that baicalin can regulate the imbalance between TREM2 and TLR4 of microglia and inhibit the activation of downstream NF-κB, thus promoting the polarization of microglia from pro-inflammatory phenotype to anti-inflammatory phenotype.

Curcumin Acetylsalicylate Extends the Lifespan of Caenorhabditis elegans.

Aspirin and curcumin have been reported to be beneficial to anti-aging in a variety of biological models. Here, we synthesized a novel compound, curcumin acetylsalicylate (CA), by combining aspirin and curcumin. We characterized how CA affects the lifespan of Caenorhabditis elegans (C. elegans) worms. Our results demonstrated that CA extended the lifespan of worms in a dose-dependent manner and reached its highest anti-aging effect at the concentration of 20 µM. In addition, CA reduced the deposition of lipofuscin or "age pigment" without affecting the reproductivity of worms. CA also caused a rightward shift of C. elegans lifespan curves in the presence of paraquat-induced (5 mM) oxidative stress or 37 °C acute heat shock. Additionally, CA treatment decreased the reactive oxygen species (ROS) level in C. elegans and increased the expression of downstream genes superoxide dismutase (sod)-3, glutathione S-transferase (gst)-4, heat shock protein (hsp)-16.2, and catalase-1 (ctl-1). Notably, CA treatment resulted in nuclear translocation of the DAF-16 transcription factor, which is known to stimulate the expression of SOD-3, GST-4, HSP-16, and CTL-1. CA did not produce a longevity effect in daf-16 mutants. In sum, our data indicate that CA delayed the aging of C. elegans without affecting reproductivity, and this effect may be mediated by its activation of DAF-16 and subsequent expression of antioxidative genes, such as sod-3 and gst-4. Our study suggests that novel anti-aging drugs may be developed by combining two individual drugs.

Heilaohuguosus A-S from the fruits of Kadsura coccinea and their hepatoprotective activity.

Phytochemical investigations on the fresh fruits of Kadsura coccinea (Lem.) A. C. Sm. have led to the isolation of fourteen undescribed 2,2'-cyclolignans named heilaohuguosus A-N, four undescribed aryltetrahydronaphthalene lignans, heilaohuguosus O-R and one tetrahydrofuran lignan, heilaohuguosu S, with twenty-seven previously described lignan analogues. Their structures and absolute configurations of heilaohuguosus A-S were established by spectroscopic methods including 1D and 2D-NMR techniques and CD experiments. All isolated compounds were evaluated for their hepatoprotective activity against APAP-induced toxicity in HepG-2 cells, four 2,2'-cyclolignans, heilaohuguosus A and L, tiegusanin I and kadsuphilol I showed good hepatoprotective activities against APAP toxicity in HepG-2 cells with cell survival rates of 53.5 ± 1.7%, 55.2 ± 1.2%, 52.5 ± 2.4%, and 54.0 ± 2.2% (positive control bicyclol, 52.1 ± 1.3%) at 10 µM, respectively.

Extract of Naotaifang, a compound Chinese herbal medicine, protects neuron ferroptosis induced by acute cerebral ischemia in rats.

OBJECTIVE: Our previous research showed that Naotaifang (a compound traditional Chinese herbal medicine) extract (NTE) has clinically beneficial effects on neurological improvement of patients with acute cerebral ischemia. In this study, we investigated whether NTE protected acute brain injury in rats and whether its effects on ferroptosis could be linked to the dysfunction of glutathione peroxidase 4 (GPX4) and iron metabolism. METHODS: We established an acute brain injury model of middle cerebral artery occlusion (MCAO) in rats, in which we could observe the accumulation of iron in neurons, as detected by Perl's staining. Using assay kits, we measured expression levels of ferroptosis biomarkers, such as iron, glutathione (GSH), reactive oxygen species (ROS) and malonaldehyde (MDA); further the expression levels of transferrin receptor 1 (TFR1), divalent metal transporter 1 (DMT1), solute carrier family 7 member 11 (SLC7A11) and GPX4 were determined using immunohistochemical analysis, real-time quantitative polymerase chain reaction and Western blot assays. RESULTS: We found that treatment with NTE reduced the expression levels of TFR1 and DMT1, reduced ROS, MDA and iron accumulation and reduced neurobehavioral scores, relative to untreated MCAO rats. Treatment with NTE increased the expression levels of SLC7A11, GPX4 and GSH, and the number of Nissl bodies in the MCAO rats. CONCLUSION: Taken together, our data suggest that acute cerebral ischemia induces neuronal ferroptosis and the effects of treating MCAO rats with NTE involved inhibition of ferroptosis through the TFR1/DMT1 and SCL7A11/GPX4 pathways.

Resolving neuroinflammation, the therapeutic potential of the anti-malaria drug family of artemisinin.

Artemisinin (Qinghaosu) and its semi-synthetic derivatives have been demonstrated to alleviate neuroinflammatory response in the central nerve system (CNS). In this review, we summarized that artemisinins are capable to treat neuroinflammtion-related CNS diseases in both direct (via regulating inflammatory process in the CNS, exerting anti-oxidative stress and neuroprotective effect, and preventing Aß accumulation) and indirect (via maintaining BBB integrity, suppressing systemic inflammation and alleviating intestinal inflammtion) manner. However, the precise mechanism of their anti-neuroinflammatory effects and potential neurotoxicity, which hindered further progress in these aspects, remains unclear. We suggest that further understanding of the PK/PD properties and structure-action relationship of atemisinin and its derivatives will facilitate the development of new therapeutics with better curative effects and safety.

[Analysis on medication rules for treatment of dementia by ancient physicians based on data mining methods].

To analyze the medication features and regularity of prescriptions of Chinese medicine in treating patients with dementia based on ancient medical records. In the article, we retrieved the ancient medical records related to the treatment of dementia (from the Han Dynasty to the late Qing period) in Chinese Medical Classics, Chinese Ancient Medical Books and digital library, and then set up a medical records normalized database. The medication features and prescription rules for dementia were analyzed by frequency statistics and association rules (Apriori algorithm, improved mutual information algorithm and complex system entropy clustering). Finally, a total of 156 prescriptions were selected, involving 123 Chinese herbs, with a total frequency of 11 747 for the herbs, and 8 core prescriptions were mined. After the association rules between the frequency and prescriptions for the treatment of dementia were determined, we found that the most commonly used herbs included Fuling (Poria), Yuanzhi (Polygalae Radix), Renshen (Ginseng Radix et Rhizoma), Shichangpu (Acori Tatarinowii Rhizoma), Gancao (Glycyrrhizae Radix et Rhizoma), Danggui (Angelicae Sinensis Radix), Maidong (Ophiopogonis Radix), Baizhu (Bletillae Rhizoma), Dihuang (Rehmanniae Radix) and Ganjiang (Zingiberis Rhizoma); the frequently-used drugs compatibility was mainly for tonifying Qi-blood, regulating Yin and Yang and inducing resuscitation. The drugs were mainly of warm nature and sweet (mild) flavor, and the channel tropism of drugs mainly distributed to the heart, liver, spleen and kidney. The core prescriptions were composed of Renshen (Ginseng Radix et Rhizoma), Fuling (Poria), Yuanzhi (Polygalae Radix), Shichangpu (Acori Tatarinowii Rhizoma), and Baizhu(Bletillae Rhizoma). In conclusion, high frequency herbs and core prescriptions reflect the prescriptions by ancient physicians mainly focus on Qi-replenishing, spleen-invigorating and heart-nourishing, but also reflect the prescription rules of nourishing Yin, enriching blood, eliminating phlegm and warming Yang for the treatment of dementia. The medication features and prescription rules for the treatment of dementia obtained by association rules are useful to guide the clinical practice of Chinese medicine in treatment of dementia.

Effects of the aqueous extract of the Chinese medicine Danggui-Shaoyao-San on rat pineal melatonin synthesis.

OBJECTIVES: The purpose of this study is to investigate if the aqueous extract of the Chinese medicine Danggui-Shaoyao-San (DSS) can increase the plasma level of melatonin and enhance the function of the pineal gland of naturally aged rats. METHODS: The rats were treated with DSS at doses of 3ml or same volume of distilled water by oral administration at 11 p.m. for three weeks. The plasma level of melatonin were measured by radioimmunoassay. The function of pineal gland were measured through three parameters: pineal beta adrenergic receptor binding investigated by [3H]DHA binding; pineal expression of NAT mRNA detected by real-time RT-PCR; phosphorylation of CREB (P-CREB) and total level of CREB (T-CREB) measured by western blot analysis. RESULTS: DSS significantly increased melatonin level at night after oral administration for 3 weeks. By measurement of pineal [3H]DHA binding, it was found DSS improved the beta-adrenergic receptors binding in pineals. The stimulatory effect of DSS on the expression of NAT mRNA in the old rat pineal gland has been demonstrated in this study. Western blot analysis showed that DSS significantly increased phosphorylation of CREB. CONCLUSIONS: Our results indicate that a downstream pathway for DSS induction of melatonin synthesis in the rat pineal gland acts via cyclic AMP-dependent cascade and transcription mechanism.