Artesunate reverses LPS tolerance by promoting ULK1-mediated autophagy through interference with the CaMKII-IP3R-CaMKKβ pathway

Role of O-GlcNAcylation in Central Nervous System Development and Injuries: A Systematic Review

The development of central nervous system (CNS) can form perceptual, memory, and cognitive functions, while injuries to CNS often lead to severe neurological dysfunction and even death. As one of the prevalent post-translational modifications (PTMs), O-GlcNAcylation has recently attracted great attentions due to its functions in regulating the activity, subcellular localization, and stability of target proteins. It has been indicated that O-GlcNAcylation could interact with phosphorylation, ubiquitination, and methylation to jointly regulate the function and activity of proteins. Furthermore, a growing number of studies have suggested that O-GlcNAcylation played an important role in the CNS. During development, O-GlcNAcylation participated in the neurogenesis, neuronal development, and neuronal function. In addition, O-GlcNAcylation was involved in the progress of CNS injuries including ischemic stroke, subarachnoid hemorrhage (SAH), and intracerebral hemorrhage (ICH) and played a crucial role in the improvement of brain damage such as attenuating cognitive impairment, inhibiting neuroinflammation, suppressing endoplasmic reticulum (ER) stress, and maintaining blood-brain barrier (BBB) integrity. Therefore, O-GlcNAcylation showed great promise as a potential target in CNS development and injuries. In this article, we presented a review highlighting the role of O-GlcNAcylation in CNS development and injuries. Hence, on the basis of these properties and effects, intervention with O-GlcNAcylation may be developed as therapeutic agents for CNS diseases.

Mechanism and therapeutic potential of traditional Chinese medicine extracts in sepsis

Sepsis is a complex syndrome characterized by multi-organ dysfunction, due to the presence of harmful microorganisms in blood which could cause mortality. Complications associated with sepsis involve multiple organ dysfunction. The pathogenesis of sepsis remains intricate, with limited treatment options and high mortality rates. Traditional Chinese medicine (TCM) has consistently demonstrated to have a potential on various disease management. Its complements include reduction of oxidative stress, inhibiting inflammatory pathways, regulating immune responses, and improving microcirculation. Traditional Chinese medicine can mitigate or even treat sepsis in a human system. This review examines progress on the use of TCM extracts for treating sepsis through different pharmacological action and its mechanisms. The potential targets of TCM extracts and active ingredients for the treatment of sepsis and its complications have been elucidated through molecular biology research, network pharmacology prediction, molecular docking analysis, and visualization analysis. Our aim is to provide a theoretical basis and empirical support for utilizing TCM in the treatment of sepsis and its complications while also serving as a reference for future research and development of sepsis drugs.

Artesunate Exerts Organ- and Tissue-Protective Effects by Regulating Oxidative Stress, Inflammation, Autophagy, Apoptosis, and Fibrosis: A Review of Evidence and Mechanisms

The human body comprises numerous organs and tissues operating in synchrony, it facilitates metabolism, circulation, and overall organismal function. Consequently, the well-being of our organs and tissues significantly influences our overall health. In recent years, research on the protective effects of artesunate (AS) on various organ functions, including the heart, liver, brain, lungs, kidneys, gastrointestinal tract, bones, and others has witnessed significant advancements. Findings from in vivo and in vitro studies suggest that AS may emerge as a newfound guardian against organ damage. Its protective mechanisms primarily entail the inhibition of inflammatory factors and affect anti-fibrotic, anti-aging, immune-enhancing, modulation of stem cells, apoptosis, metabolic homeostasis, and autophagy properties. Moreover, AS is attracting a high level of interest because of its obvious antioxidant activities, including the activation of Nrf2 and HO-1 signaling pathways, inhibiting the release of reactive oxygen species, and interfering with the expression of genes and proteins associated with oxidative stress. This review comprehensively outlines the recent strides made by AS in alleviating organismal injuries stemming from various causes and protecting organs, aiming to serve as a reference for further in-depth research and utilization of AS.

The effect of artesunate to reverse CLP-induced sepsis immunosuppression mice with secondary infection is tightly related to reducing the apoptosis of T cells via decreasing the inhibiting receptors and activating MAPK/ERK pathway

T cells play an important role in regulating immune system balance. Sepsis-associated immunosuppression causes apoptosis of T cells and a decrease in their number. Previously, artesunate was found to have an immunomodulatory effect on immunosuppression in model mice with cecal ligation and puncture (CLP)-induced sepsis. In the present study, mouse sepsis models of CLP and CLP with secondary infection were established and treated with artesunate in order to examine the effect of artesunate on adaptive immune response in sepsis-related immunosuppression. The results showed that artesunate treatment could increase the survival rate of CLP mice with secondary Pseudomonas aeruginosa infection, increase the bacterial clearance rate, and also increase the level of the pro-inflammatory cytokine TNF-α. In addition, artesunate resulted in an increase in the number of T cells, CD4+ T cells and CD8+ T cells, and inhibited CD4+ and CD8+ T-cell apoptosis. Artesunate was also found to inhibit the expression of the inhibitory receptors of PD-1, CTLA-4, and BTLA, but it did not affect the expression of Tim-3. Additionally, artesunate significantly increased the phosphorylated ERK level of CD4+ T cells and CD8+ T cells and inhibited mitochondrial pathway-mediated apoptosis in CLP mice with Pseudomonas aeruginosa infection. These findings reveal that artesunate has an immunomodulatory effect on the adaptive immune response in sepsis. These effects include an increase in the numbers of T cells, CD4+ T cells, and CD8+ T cells through inhibition of the expression of inhibitory receptors and promotion of the MAPK/ERK pathway.

Vitamin D receptor (VDR) on the cell membrane of mouse macrophages participates in the formation of lipopolysaccharide tolerance: mVDR is related to the effect of artesunate to reverse LPS tolerance

It is unclear whether membrane vitamin D receptor (mVDR) exists on the macrophage membrane or whether mVDR is associated with lipopolysaccharide (LPS) tolerance. Herein, we report that interfering with caveolae and caveolae-dependent lipid rafts inhibited the formation of LPS tolerance. VDR was detected as co-localized with membrane molecular markers. VDR was detected on the cell membrane and its level was higher in LPS-tolerant cells than that in only LPS treatment cells. Anti-VDR antibodies could abolish the effect of artesunate (AS) to reverse LPS tolerance, and the wild-type peptides (H397 and H305) of VDR, but not the mutant peptide (H397D and H305A), led to the loss of AS's effect. AS decreased the mVDR level in LPS-tolerant cells. In vivo, AS significantly reduced VDR level in the lung tissue of LPS-tolerant mice. In summary, mVDR exists on the cell membrane of macrophages and is closely associated with the formation of LPS tolerance and the effects of AS. Video Abstract.

Sublethal chlorantraniliprole exposure induces autophagy and apoptosis through disrupting calcium homeostasis in the silkworm Bombyx mori

The intensive application of chlorantraniliprole (CAP) leaves residues in the environment, posing a potential threat to non-target organisms. In the present study, we investigated the adverse effects of sublethal CAP exposure on Bombyx mori. Sublethal CAP (0.02 mg/L) was shown to induce the release of intracellular Ca²⁺ in BmN cells. Meanwhile, Ca²⁺ -dependent genes were induced in the midgut at 72 h after CAP (0.01 mg/L) exposure, and damaged mitochondria, autophagosomes, nuclear membrane rupture and condensed chromatin were observed. Moreover, the key genes in the oxidative phosphorylation pathway were significantly down-regulated. The transcript levels of autophagy-related genes ATG6 and ATG8 were significantly up-regulated, and the protein levels of LC3-II and ATG7 were significantly increased by 3.72- and 3.33-fold, respectively. Additionally, the transcript levels of the upstream genes in the apoptosis pathway (calpain and Apaf-1) were significantly up-regulated, the protein levels of the downstream gene caspase 3 and its cleaved form were significantly up-regulated by 1.97- and 4.55-fold, respectively, consistent with the elevated caspase 3 activity at 72 h. Collectively, these findings demonstrate that intracellular Ca²⁺ release induced by sublethal CAP inhibits oxidative phosphorylation pathway, which causes mitochondrial dysfunction, leading to autophagy and apoptosis in the midgut of B. mori.

Molybdenum and cadmium co-exposure induces CaMKKβ/AMPK/mTOR pathway mediated-autophagy by subcellular calcium redistribution in duck renal tubular epithelial cells

Excessive molybdenum (Mo) and cadmium (Cd) are toxic environmental pollutants. Our previous research confirmed excessive Mo and Cd co-induced calcium homeostasis disorder and autophagy in duck kidneys, but how calcium ion (Ca²⁺) regulates autophagy is unclear. The results revealed that the Mo- and/or Cd-induced cytosolic Ca²⁺ concentration ([Ca²⁺]_c) increase mainly came from intracellular calcium stores. Mo and/or Cd caused mitochondrial Ca²⁺ content ([Ca²⁺]_mit) and [Ca²⁺]_c increase with endoplasmic reticulum (ER) Ca²⁺ content ([Ca²⁺]_ER) decrease and upregulated calcium homeostasis-related factor expression levels, but 2-Aminoethoxydiphenyl borate (2-APB) reversed subcellular Ca²⁺ redistribution. Increased Phospholipase C (PLC) and inositol 1,4,5-trisphosphate (IP₃) activities and inositol 1,4,5-trisphosphate receptor (IP₃R) expression level were observed in Mo- and/or Cd-treated cells, which was reversed by the PLC inhibitor U-73122. 2-APB and 1,2-Bis (2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (BAPTA-AM) addition mitigated [Ca²⁺]_c and autophagy (variations in microtubule-associated protein light chain 3 (LC3), LC3B-II/LC3B-I, autophagy related 5 (ATG5), sequestosome-1(P62), programmed cell death-1 (Beclin-1) and Dynein expression levels, LC3 puncta, autophagosomes and acid vesicle organelles) under Mo and/or Cd treatment, respectively, while thapsigargin (TG) had the opposite impacts. Additionally, the calmodulin-dependent protein kinase kinase β (CaMKKβ) inhibitor STO-609 reversed the increased CaMKKβ, adenosine 5'-monophosphate-activated protein kinase (AMPK), Beclin-1, and LC3B-II/LC3B-I protein expression levels and reduced mammalian target of rapamycin (mTOR) and P62 protein expression levels in Mo- and/or Cd-exposed cells. Collectively, the results confirmed that [Ca²⁺]_c overload resulted from PLC/IP₃/IP₃R pathway-mediated ER Ca²⁺ release, and then activated autophagy by the CaMKKβ/AMPK/mTOR pathway in Mo- and/or Cd-treated duck renal tubular epithelial cells.

New Insights into Artesunate as a Pleiotropic Regulator of Innate and Adaptive Immune Cells

Artesunate, one of the derivatives of artemisinin (“qinghaosu” in Chinese), is known as an antimalarial drug with high efficiency and low toxicity. Of interest, emerging evidences suggest that artesunate also possesses an immunomodulatory effect during innate and adaptive immune responses in cell types and context-dependent manner. Although it shows promising application in many diseases, such as inflammatory diseases, hypersensitivity, autoimmune diseases, and cancers, little is known about underlying molecular. In this review, we summarize recent advances of how artesunate regulates innate and adaptive immune cells. In addition, its potential application in immune-related diseases is also highlighted.

In vivo assessment of molybdenum and cadmium co-induce nephrotoxicity via causing calcium homeostasis disorder and autophagy in ducks (Anas platyrhyncha)

Excess molybdenum (Mo) and cadmium (Cd) are widespread environmental and industrial metal pollutants. To evaluate the combined effects of Mo and Cd on calcium homeostasis and autophagy in duck kidneys. 160 healthy 7-day-old ducks (Anas platyrhyncha) were randomized into 4 groups and given to a basic diet, adding various doses of Mo or/and Cd for 16 weeks. On the 4th, 8th, 12th and 16th weeks, kidney tissues were collected. The study exhibited that Mo or/and Cd caused histological abnormality, reduced the activities of Ca2+ ATPase, Mg2+ ATPase, Na+-K+ ATPase and Ca2+-Mg2+ ATPase, K and Mg contents, and increased Na and Ca contents, upregulated CaMKKβ, CaMKIIɑ, CaN, IP3R, GRP78, GRP94, CRT mRNA levels and CaMKIIɑ, CaN, IP3R protein levels. Moreover, exposure to Mo or/and Cd notably promoted the amount of autophagosomes and LC3II immunofluorescence, upregulated AMPKα1, ATG5, Beclin-1, LC3A, LC3B mRNA levels and Beclin-1, LC3II/LC3I protein levels, downregulated mTOR, Dynein, P62 mRNA levels and P62 protein level. The changes of above indicators in combined group were more obvious. Overall, the results suggest that Mo and Cd co-exposure may can synergistically induce nephrotoxicity via causing calcium homeostasis disorder and autophagy in ducks.

The crosstalk between pattern-recognition receptor signaling and calcium signaling

The innate immune system is the first line of host defense, and it is capable of resisting both exogenous pathogenic challenges and endogenous danger signals via different pattern recognition receptors (PRRs), including Toll-like receptors, retinoic acid-inducible gene-1 (RIG-1)-like receptors, cytosolic DNA sensors, as well as nucleotide-binding oligomerization domain (NOD)-like receptors. After recognizing the pathogen-associated molecular patterns from exogenous microbes or the damage-associated molecular patterns from endogenous immune-stimulatory signals, these PRRs signaling pathways can induce the expression of interferons and inflammatory factors against microbial pathogen invasion and endogenous stresses. Calcium (Ca²⁺) is a second messenger that participates in the modulation of various biological processes, including survival, proliferation, apoptosis, and immune response, and is involved in diverse diseases, such as autoimmune diseases and virus infection. To date, accumulating evidence elucidated that the PRR signaling exhibited a regulatory effect on Ca²⁺ signaling. Meanwhile, Ca²⁺ signaling also played a critical role in controlling biological processes mediated by the PRR adaptors. Since the importance of these two signalings, it would be interesting to clarify the deeper biological implications of their interplays. This review focuses on the crosstalk between Ca²⁺ signaling and PRR signaling to regulate innate immune responses.

Artesunate attenuates foam cell formation by enhancing cholesterol efflux

Background

Atherosclerosis is the main cause of many cardiovascular diseases and the second leading cause of death in elderly people. The formation of intimal macrophage-derived foam cells is a major feature of early atherosclerotic lesions. Little is known about the effects of artesunate (ART) on macrophage-derived foam cell formation.

Methods

Oil red O staining was employed to detect foam cell formation; colorimetric analysis was employed for cholesterol measurement; quantitative real time polymerase chain reaction (qRT-PCR) and western blot analysis were employed to assess messenger RNA (mRNA) and protein expression, respectively; enzyme-linked immunosorbent assay (ELISA) analyses were used to observe interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) release; and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays were used to examine cell viability.

Results

It was revealed that ART attenuated oxidized low-density lipoprotein (ox-LDL)-induced foam cell formation from THP-1-derived macrophages by decreasing cholesterol accumulation, and the effect might have occurred via enhanced cholesterol efflux. Additionally, ART decreased toll-like receptor 4 (TLR4) expression, increased adenosine triphosphate (ATP)-binding cassette transporter A1 (ABCA1) and ATP-binding cassette transporter G1 (ABCG1) expression, and reduced the secretion of IL-6 and TNF-α.

Conclusions

This study showed that ART attenuated the ox-LDL-induced formation of foam cells from THP-1-derived macrophages by increasing ABCA1 and ABCG1 expression via inhibiting TLR4 expression and reducing TNF-α and IL-6 secretion from macrophages induced by ox-LDL, which ultimately decreased the accumulation of cholesterol. It is worthwhile further investigate ART as a potential drug for the treatment of atherosclerosis.