Caspases: enemies within

Loss of non-muscle myosin II Zipper leads to apoptosis-induced compensatory proliferation in Drosophila

Drosophila Non-muscle myosin II Zipper (Zip) belongs to a functionally divergent class of molecular motors that play a vital role in various cellular processes including cell adhesion, cell migration, cell protrusion, and maintenance of polarity via its cross-linking property with actin. To further determine its role in cell proliferation and apoptosis, we carried out Zip loss of function studies that led to compromised epithelial integrity in Drosophila wing imaginal discs as evident from the perturbed expression pattern of cell-cell junction proteins Cadherin, Actin, and Armadillo. Disruption of these adhesion proteins resulted in the cells undergoing apoptosis as evident from the increased level of effector caspase, cDcp-1. The induction of cell death due to the loss of function of Zip was accompanied by proliferation as apparent from increased PH3 staining. The control of apoptosis-induced compensatory proliferation lies under the caspase cascade. We carried out experiments that suggested that the apical caspase Dronc is responsible for the apoptosis-induced compensatory proliferation due to the loss of Zip function and not the effector caspase Drice/Dcp-1. Further, it was observed that Dronc leads to the subsequent activation of Jun N-terminal kinase pathway (JNK) pathway and Wingless (Wg) mitogen that diffuse to the neighboring cells and prompt them to undergo cell division. Taken together, our results suggest that loss of function of Zip leads to apoptosis-induced compensatory proliferation.

Manipulating ICG J-Aggregation and Disaggregation for Imaging-Guided Cancer Therapy with Self-Reporting Efficiency

Integrating imaging guided therapy and therapeutic effect self-reporting would highly benefit clinic applications. J-type aggregates of organic dyes with corresponding photothermal effect have made them popular agents for photoacoustic (PA) imaging and photothermal therapy (PTT). However, approaches to manipulate the disaggregation of J-aggregate with corresponding organic dye fluorescence recovery have rarely been reported, which limits the full exploration of J-aggregate in therapeutic applications. Herein, indocyanine green (ICG) J-aggregate is designed in a micelle structure (J-ICG-Micelle) by co-assembling ICG with DSPE-Pep-PEG, which contains peptide KADEVDAC that recognized and cleaved by caspase-3. Taking advantages of the red-shifted absorbance of J-ICG-Micelle, it achieves PA imaging navigated delivery process with an indication of tumor accumulation time and position to perform PTT. Corresponding cell apoptosis and caspase-3 generation cleaves peptide KADEVDAC and results in fluorescence recovery of ICG, which self-reports therapeutic effect in real time, and the intensity for fluorescence recovery demonstrates similar tendency as H&E staining at tumor sections. The as-presented J-ICG-Micelle would have a promising contribution to precise cancer therapy.

Caspases: structural and molecular mechanisms and functions in cell death, innate immunity, and disease

Caspases are critical regulators of cell death, development, innate immunity, host defense, and disease. Upon detection of pathogens, damage-associated molecular patterns, cytokines, or other homeostatic disruptions, innate immune sensors, such as NLRs, activate caspases to initiate distinct regulated cell death pathways, including non-lytic (apoptosis) and innate immune lytic (pyroptosis and PANoptosis) pathways. These cell death pathways are driven by specific caspases and distinguished by their unique molecular mechanisms, supramolecular complexes, and enzymatic properties. Traditionally, caspases are classified as either apoptotic (caspase-2, -3, -6, -7, -8, -9, and -10) or inflammatory (caspase-1, -4, -5, and -11). However, extensive data from the past decades have shown that apoptotic caspases can also drive lytic inflammatory cell death downstream of innate immune sensing and inflammatory responses, such as in the case of caspase-3, -6, -7, and -8. Therefore, more inclusive classification systems based on function, substrate specificity, or the presence of pro-domains have been proposed to better reflect the multifaceted roles of caspases. In this review, we categorize caspases into CARD-, DED-, and short/no pro-domain-containing groups and examine their critical functions in innate immunity and cell death, along with their structural and molecular mechanisms, including active site/exosite properties and substrates. Additionally, we highlight the emerging roles of caspases in cellular homeostasis and therapeutic targeting. Given the clinical relevance of caspases across multiple diseases, improved understanding of these proteins and their structure-function relationships is critical for developing effective treatment strategies.

The regulatory mechanisms for beef tenderization by the calcium-independent phospholipase A2 activity of Peroxiredoxin 6

This study investigated the effect of the inhibition of the activity of Ca2+-independent Phospholipase A2 (iPLA2) of Peroxiredoxin 6 (Prdx6) on beef tenderization in the early post-mortem period. Longissimus lumborum (LL) were incubated with or without the inhibitor of iPLA2 activity of Prdx6 (MJ33) for 1, 6, 12, 24, or 36 h, followed by incubation with or without the H2O2. iPLA2 activity, troponin T and desmin, Ca2+ concentration, calpain-1, caspases, apoptosis rate, and cell morphology were examined. It was found that the reduction of the iPLA2 activity of Prdx6 was found to promote degradation of cytoskeletal proteins (troponin T, desmin). The inhibition of the iPLA2 activity of Prdx6 suppressed the caspases activation. This reduced the apoptotic rate, but increased Ca2+ concentrations and calpain-1 activation, outcomes that promoted beef tenderization. This mechanistic characterization confirms the application of Prdx6 as a biomarker for beef of high quality and consumer acceptance.

Investigation of the anti-inflammatory, anti-oxidant and anti-apoptotic activity of 18β- glycyrrhetinic-acid on the model of LPS-induced lung injury in rats

INTRODUCTION

Our aim was to investigate the protective effects of 18β-Glycyrrhetinic-acid (50 and 100 mg/kg i.g) on LPS-induced rat sepsis model by analyzing some immune mechanisms including inflammation, apoptosis, and oxidative stress parameters by different techniques such as Mallory's Trichome staining, ELISA, tissue biochemistry and Western Blotting.

METHODS

Forty-eight Sprague Dawley rats divided into 6 groups as follows: (i) Control, (ii) DMSO, (iii) LPS induced-Sepsis, (iv) LPS induced-Sepsis+ 18β-GA 50 mg/kg, (v) LPS induced-Sepsis + 18β-GA 100 mg/kg, (vi) 18β-GA 100 mg/kg. The pro-inflammatory cytokine (IFNγ, IL-1ß, TNF- α) levels were measured by ELISA technique. All rat's lung tissues micrographed with Mallory's Trichome stain. Oxidative stress parameters (MDA, GSH, SOD, NRF2, and HO-1), TLR4 signaling, and apoptotic proteins (Bcl-2 and Caspase-3) were detected by using tissue biochemistry and Western blotting.

RESULTS

LPS administration caused a significant increase in all pro-inflammatory cytokine and oxidant levels. Shedding of bronchiolar epithelium, thickening of alveolar septa and vascular dilatation in LPS groups' lung tissue were revealed according to the histopathological findings. The H-scores of 18β-GA50 +LPS and 18β-GA100 +LPS groups were significantly lower than LPS groups' (p < 0.05). When lung tissue protein expression profiles were analyzed for HO-1, TLR4, IL-1β, TNF-α, Bcl-2, and Caspase-3 expression was higher in the LPS group than in the control. In addition, NRF2 and Bcl-2 protein expressions were higher in control, DMSO and 18β-GA100 groups, while it was the lowest level in LPS group.

CONCLUSION

18β-GA demonstrates significant protective effects against LPS-induced lung injury in rats by modulating various immune mechanisms. These findings indicate that 18β-GA, particularly at the higher dose, may be a potential therapeutic agent in managing sepsis by mitigating inflammation, oxidative stress, and apoptosis in lung tissue. The inflammation and oxidative stress parameters were decreased and the apoptotic markers were increased in treatment group. Further molecular studies should be performed to investigate the roles of some significant cellular signaling pathways.

Agrimonia Pilosa Extract suppresses NSCLC growth through regulating PI3K/AKT/Bcl-2 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Agrimonia Pilosa is a traditional Chinese medicine with a long history, which is often used in clinic alone or in combined with other Chinese herb medicine to anti-inflammatory, hemostasis and treat many types cancers, including lung cancer. Agrimonia Pilosa Extract (APE) is extracted from the Agrimonia Pilosa. The potential molecular mechanism of APE on the non-small cell lung cancer remains unclear.

AIM OF THIS STUDY

The aim of this study was to investigate the molecular mechanism of APE induced apoptosis in NSCLC cells and its effect on metabolism.

MATERIALS AND METHODS

Constructed mouse transplantation tumor models to evaluate the anti-tumor effect of APE by pharmacodynamics test, histological staining and TUNEL staining. Analyzed alterations in metabolites and metabolic pathways in serum and tumor tissues from tumor-bearing mice by liquid chromatography-mass spectrometry (LC-MS)-based untargeted metabolomics. In addition, the key proteins and genes on the signaling pathway were verified by Western blotting (WB) and real-time fluorescence quantitative PCR(RT-qPCR) to reveal the anti-tumor mechanism of APE.

RESULTS

APE inhibited tumor growth by promoting apoptosis and caused metabolic changes. Specifically, they inhibited the PI3K/AKT/Bcl-2 signaling pathway while upregulating apoptotic markers such as TP53, Bax, Caspase-3, and Cytochrome c. Through metabolomics analysis of mouse serum and tumor tissue, 120 different metabolites were identified, including glutamate, PC(24:0/18:0), and LysoPE(18:0/0). Among these, 13 serum metabolites were down-regulated, 16 were up-regulated, 28 tumor metabolites were down-regulated, and 63 were up-regulated. Studies indicate that APE can regulate metabolic disorders associated with non-small cell lung cancer by influencing pathways like glycerophospholipid metabolism, amino acid metabolism, and the TCA cycle, thereby inducing cell apoptosis and leading to significant metabolic changes.

CONCLUSIONS

In this study, APE affected the apoptosis of non-small cell lung cancer cells by regulating the PI3K/AKT/Bcl-2 signal transduction pathway and various metabolic pathways thereby inhibited the growth of tumor cells.This deepened the understanding of the metabolic characteristics and apoptosis-related pathways in APE intervened NSCLC, and provided a reference for further research on the mechanism of action of its anticancer drugs.

Robust Peptide-Functionalized Gold Nanoparticles via Ethynyl Bonding for High-Fidelity Bioanalytical Applications

While Au-S bonds have been widely applied in preparing gold nanoparticle (AuNP) bioconjugates for biosensing, cell imaging, and biomedical research, biothiols in complex biological environments can seriously interfere with the stability of the conjugates due to ligand exchange. Herein, we communicate a robust and fast strategy for constructing peptide-functionalized AuNP conjugates (PFCs) using the Au-C≡C bond, which can be completed within two minutes. The resulting Au-C≡C PFCs exhibited better stability and resistance to biothiols than the corresponding Au-S PFCs, and also demonstrated excellent stability in high salt concentration, a wide range of pH values, and varying temperatures. The mechanism of Au-C≡C conjugation was confirmed using molecular dynamics simulation and X-ray photoelectron spectroscopy (XPS). The Au-C≡C PFCs significantly improved the signal fidelity in an intracellular caspase imaging assay. Overall, the developed strategy provides a promising approach for constructing AuNP nanoprobes, allowing reliable detection and broadening the potential for diverse biological applications.

Recent Advances in Enzyme-Activated Dual-Locked Probes for Biological Applications

Enzymes catalyze reactions involved in diverse physiological, pathological, and pharmacological processes. By employing the optical probe, fluorescence imaging enables non-invasive, real-time detection and assessment of disease states based on enzymatic activity. However, most enzyme-activated probes are single-locked probes that respond to a single biomarker. In comparison to single-locked probes, enzyme-activated dual-locked probes can effectively minimize the occurrence of false-positive signals, circumvent the problem of low specificity associated with biologically active substances, and facilitate precise imaging. This review systematically summarizes the design and application of dual-locked probes in disease diagnosis, with the aim of providing inspiration for researchers in the field.

Programming a multiplex lanthanide nanoparticle for customized cancer treatment with real-time efficiency feedback

Customized cancer therapy relies on timely therapeutic effect evaluation to provide prescription adjustment for individual cases. However, currently reported therapeutic reagents are rarely integrated with imaging probes for self-evaluation of effects. Contrast imaging agents to measure tumor size changes must be administrated separately after therapy, complicating the therapeutic process and delaying reporting time. Herein, we design a customized therapy platform (LNPs-RB/Pep/cRGD) by conjugating lanthanide nanoparticles (LNPs) with the photosensitizer rose bengal, a caspase-3 substrate peptide (with Cy7.5 labelled at the terminal), and the tumor-targeting molecule cRGD. LNPs exhibit NIR-IIb downconversion luminescence under 980 nm/808 nm excitations for in vivo imaging, and visible upconversion luminescence under high-power 980 nm excitation for photodynamic therapy (PDT). By sequentially programming NIR excitation wavelength and power, NIR-IIb-imaging guided PDT and real-time cancer cell apoptosis imaging are achieved as therapeutic efficiency feedback. PDT induces cell apoptosis, generating caspase-3, which cleaves Cy7.5-containing peptide fragments from LNPs. This process corresponds to a recovery in vivo of NIR-IIb ratiometric imaging at 808 nm versus 980 nm excitation. The cleaved Cy7.5-containing peptide fragment is cleared into urine for NIR imaging. Both cell apoptosis imaging processes are completed 12 h after PDT, which is 7 days earlier than tumor size measurement. Therefore, customized therapy is achieved by timely adjusting PDT dosage, enhancing therapeutic efficacy.

Exposure of Parental Zebrafish to Difenoconazole throughout Their Life Cycle May Lead to Developmental Toxicity in the F1 Generation through Epigenetic Changes in Gametes, Impaired Nutrient Supply from the Ovum, and Maternal Transfer of Difenoconazole

Difenoconazole is a widely used agricultural fungicide that has been frequently detected in aquatic environments. Given its stable presence in aquatic environments, long-term exposure of wild fish may pose a risk to offspring embryonic development. This study demonstrated that exposure of zebrafish to environmental concentrations of difenoconazole throughout their life cycle resulted in abnormal development of offspring embryos/larvae, including decreased heart rate, delayed hatching, increased malformation rate, shortened body length, and increased mortality. These changes were significantly correlated with the affected apoptosis, autophagy, energy metabolism and MAPK signaling pathways in F1 generation. This transgenerational toxic effect results from epigenetic alterations in gametes, impaired nutrient supply from the ovum, and maternal transfer of difenoconazole. After exposure to difenoconazole, the development of female fish offspring was affected more than that of male fish offspring, which was mainly caused by the impaired nutrient supply from the ovum and the maternal transfer of difenoconazole. Because this transgenerational developmental toxicity was observed at environmental levels, difenoconazole may pose a threat to the survival of wild larvae and therefore a risk to wild fish populations.

Icariin improves erectile function in spontaneously hypertensive rats by downregulating GRK2 in penile cavernous tissue

BACKGROUND

Hypertension is an independent risk factor for erectile dysfunction (ED). Icariin can improve erectile function of spontaneous hypertensive rats (SHRs). GRK2 is closely related to the phosphorylation of eNOS and endothelial function.

AIM

To explore whether icariin can improve erectile function in SHRs by regulating the expression of GRK2 in penile cavernous tissue.

METHODS

Eight-week-old WKY and SHR rats were randomly divided into four groups (n = 6 per group) as follows: WKY, WKY + icariin, SHR and SHR + icariin. The WKY + icariin and SHR + icariin groups were treated with 10 mg/kg/day icariin. After 4 weeks, the ICPmax/mean arterial pressure (MAP), serum testosterone, the levels of GRK2, p-AKT/AKT, p-eNOS/eNOS, and caspase-3; the protein interaction between GRK2 and AKT; the levels of nitric oxide (NO), superoxide dismutase (SOD), and malondialdehyde (MDA); and the level of apoptosis in rat penile cavernous tissue were measured.

OUTCOME

The expression of GRK2 in penile cavernous tissue of SHR was significantly higher than that in WKY rats, resulting in the inhibition of the AKT/eNOS/NO pathway, increased levels of oxidative stress and apoptosis, and the impairment of erectile function.

RESULTS

The ICPmax/MAP ratio in the SHR group was significantly lower than those in WKY and SHR + icariin groups (P < .01). In the SHR + icariin group, the expression levels of GRK2 and caspase-3, the interaction between GRK2 and AKT, the level of MDA and the rate of apoptosis in the penile cavernous tissue were significantly lower, and the levels of p-AKT and p-eNOS, the p-AKT/AKT and p-eNOS/eNOS ratios, and NO and SOD were significantly greater than those in the SHR group (P < .01).

CLINICAL IMPLICATIONS

Icariin may improve the erectile function of hypertension by downregulating GRK2 expression in penile cavernous tissue.

STRENGTHS AND LIMITATIONS

The specific mechanism via which icariin downregulates GRK2 needs to be further elucidated.

CONCLUSION

Icariin downregulates the expression of GRK2 in the penile cavernous tissue of SHRs, upregulates the AKT/eNOS/NO pathway, decreases oxidative stress and apoptosis, and ultimately improves erectile function.

Research Progress on Antibacterial Applications of Bioactive Materials in Wound Infections: Design, Challenges, and Prospects

Bacterial wound infections pose a significant threat to global health, exacerbated by the increase in multidrug-resistant bacteria (MDRB) and the formation of elastic biofilms. This review explores the transformative potential of bioactive materials in addressing these challenges, focusing on their design, mechanisms of action, and therapeutic effects. In vivo, bioactive materials are designed to respond to unique bacterial microenvironment (BME), utilizing enzyme activity, controlled gas release, surface functionalization, and immune regulation to combat infections. In vitro, this review provides a comprehensive overview of the latest advances in the rational design of these materials, emphasizing the synergistic integration of structural modifications (such as size and morphology) with external physical stimuli (such as light, sound, electricity, magnetism, and force) to enhance antibacterial performance. Finally, the outstanding challenges and prospects in this rapidly evolving field are discussed.

Caspase cleavage of influenza A virus M2 disrupts M2-LC3 interaction and regulates virion production

Influenza A virus (IAV) Matrix 2 protein (M2) is an ion channel, required for efficient viral entry and egress. M2 interacts with the small ubiquitin-like LC3 protein through a cytoplasmic C-terminal LC3-interacting region (LIR). Here, we report that M2 is cleaved by caspases, abolishing the M2-LC3 interaction. A crystal structure of the M2 LIR in complex with LC3 indicates the caspase cleavage tetrapeptide motif (82SAVD85) is an unstructured linear motif that does not overlap with the LIR. IAV mutant expressing a permanently truncated M2, mimicking caspase cleavage, exhibit defects in M2 plasma membrane transport, viral filament formation, and virion production. Our results reveal a dynamic regulation of the M2-LC3 interaction by caspases. This highlights the role of host proteases in regulating IAV exit, relating virion production with host cell state.

The Oxidative Stress of Human Sperm Cryopreservation

Due to their negligible cytoplasm and composition of the sperm plasmalemma, spermatozoa are particularly vulnerable to lipid peroxidative damage induced by reactive oxygen species (ROS). Most ROS are referred to as free radicals because they have unpaired electrons, causing them to scavenge electrons from atoms within tissues, resulting in oxidative damage to cellular components including cell membranes, intracellular organelles, and DNA. The potential consequences of oxidative stress include impaired sperm function, DNA fragmentation, and apoptosis. Understanding the mechanisms that mediate sperm damage during cryopreservation is key to the development of improved sperm freezing media formulations and methodology to mitigate its occurrence. Historically, elucidation of those mechanisms has proven largely elusive and is complicated by the positive role that ROS also play as messengers in redox signaling and the different pathways that mediate sperm DNA damage and apoptosis. More recently, oxidative stress has been revealed as the most likely suspect in cryopreservation-induced sperm DNA damage. This narrative review was intended to provide an in-depth analysis of the mechanisms involved and offer insight into possible improvements in sperm cryopreservation.

MYBL2 promotes cell proliferation and inhibits cell apoptosis via PI3K/AKT and BCL2/BAX/Cleaved-caspase-3 signaling pathway in gastric cancer cells

The transcription factor MYB proto-oncogene like 2 (MYBL2) has been reported to be involved in the occurrence and development of various tumors, however, its role in gastric cancer (GC) remains to be elucidated. In this study, the Kaplan-Meier plotter was used to evaluate the prognostic value of different MYBL2 expression levels in GC patients. The UALCAN database were applied to analyze the relationships between MYBL2 and clinicopathological characteristics of GC. GC cell proliferation, cell cycle and apoptosis were determined by CCK-8 and flow cytometry assays, and proteins were examined by Western blot analysis. Next, signaling pathway enrichment analysis of MYBL2-related genes and protein expression were analyzed by Gene Set Enrichment Analysis (GSEA) and Western blot assays. The results found that MYBL2 expression was significantly upregulated in GC compared with adjacent non-malignant tissues and associated with poor patient survival, tumor, stages and lymph node metastasis. Forced expression of MYBL2 could promote cell proliferation, resulting in an accelerated S phase progression and inhibiting cell apoptosis in GC cells. Conversely, MYBL2 silencing inhibited cell proliferation, induced G2/M phase arrest and promoted cell apoptosis in GC cells. Mechanistically, Western blot analysis showed that MYBL2 silencing decreased the expression of BCL2 and upregulated the expression of Cleaved-caspase-3 and BAX in HGC-27 cells. Conversely, MYBL2 overexpression in AGS cells resulted in the opposite effects. Furthermore, enforced expression of MYBL2 activated the PI3K/AKT signaling pathway, especially AKT phosphorylation. Additionally, the AKT inhibitor MK2206 significantly reversed the proliferation capacity of GC cells induced by MYBL2 overexpression. Therefore, these results suggest that upregulated expression of MYBL2 contributes to GC cell growth and inhibits cell apoptosis by regulating the PI3K/AKT and BCL2/BAX/Cleaved-caspase-3 signaling pathways in GC cells indicating that MYBL2 may be a new therapeutic target and prognostic marker for GC.

Cell death in tumor microenvironment: an insight for exploiting novel therapeutic approaches

Cell death is critical in tumor biology. The common cancer therapies can cause cell death and alleviate tumor, while the cancer cells can develop a resistance to cell death and survive from the therapies. Thus, not only observing the alternative mechanisms of tumor cells resistant to cell death, but also understanding the intricate dynamics of cell death processes within the tumor microenvironment (TME), are essential for tailoring effective therapeutic strategies. High-throughput sequencing technologies have revolutionized cancer research by enabling comprehensive molecular profiling. Recent advances in single cell sequencing have unraveled the heterogeneity of TME components, shedding light on their complex interactions. In this review, we explored the interplay between cell death signaling and the TME, summarised the potential drugs inducing cell death in pre-clinical stage, reviewed some studies applying next-generation sequencing technologies in cancer death research, and discussed the future utilization of updated sequencing platforms in screening novel treatment methods targeted cell death. In conclusion, leveraging multi-omics technologies to dissect cell death signaling in the context of the TME holds great promise for advancing cancer research and therapy development.

Intraductal chemotherapy for triple-negative breast cancer: a pathway to minimally invasive clinical treatment

Triple-negative breast cancer (TNBC) is traditionally treated with systemic chemotherapy, often resulting in significant off-target toxicity. In this study, we assess the efficacy of intraductal chemotherapeutic delivery, aimed at reducing systemic side effects. Using an in situ TNBC model, created by intraductal injection of 4T1-luc cells, we identified day 3 post-tumor implantation as an optimal early intervention point. Echocardiographic analysis confirmed that intraductal administration of eribulin (ERI) or doxorubicin (DOX) did not cause cardiac dysfunction or apoptosis. Our results demonstrate that intraductal delivery of ERI and DOX significantly enhances anti-tumor and anti-metastatic effects. Mechanistically, ERI followed by DOX increased intratumoral perfusion, improved drug concentration, reversed epithelial-mesenchymal transition, and inhibited tumor cell invasion and metastasis. Additionally, this approach triggered immunogenic cell death and activated a systemic anti-tumor immune response. These findings underscore the potential of intraductal chemotherapy as a safe, highly effective approach, offering a preclinical foundation for minimally invasive TNBC therapies.

High-intensity interval training attenuates renal injury induced by myocardial ischemia-reperfusion in rats

BACKGROUND

High-intensity interval training (HIIT) has been recognized as an effective form of short-duration exercise. The purpose of this study was to assess whether HIIT could reduce renal injury induced by myocardial ischemia-reperfusion (MIR) in rats.

METHODS

Male Sprague-Dawley rats were randomly assigned to the Sham (SHAM), coronary artery occlusion (CAO), HIIT, and ischemic precondition (IPC) groups. Rats underwent 40 minutes of left anterior descending CAO under anesthesia, followed by 3 hours of reperfusion, to induce MIR. Postsurgery, rats were sacrificed, and their blood, heart, and kidney tissues were examined. The HIIT group underwent 4 weeks of HIIT training before surgery.

RESULTS

HIIT intervention significantly reduced renal injury after MIR and the concentrations of blood urea nitrogen (BUN) and creatinine (CRE) in the serum. Moreover, proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6, were significantly decreased, while the anti-inflammatory cytokine IL-10 was significantly increased in the serum. Additionally, HIIT intervention suppressed the expression of FoxO1, Bax/Bcl-2 ratio, TNF-α, and cleaved-caspase-3/caspase-3 ratio in kidney tissues, ultimately reducing renal cell apoptosis.

CONCLUSION

This study is the first to demonstrate that HIIT has effects similar to IPC, significantly reducing renal injury after MIR. HIIT regulates the production of proinflammatory and anti-inflammatory cytokines and inhibits renal cell apoptosis, thereby reducing the occurrence of cardiorenal syndrome.

Progress in Research on Regulated Cell Death in Cerebral Ischaemic Injury After Cardiac Arrest

Ischaemic damage to the brain is the main cause of brain injury after cardiac arrest. The current treatment focuses on early reperfusion, but reperfusion tends to cause reperfusion injury, which is a significant problem. Cell death is an irreversible and normal end to cell life, playing key roles in maintaining the homeostasis and development of multicellular organisms. To date, cell death can be classified into two categories: accidental cell death (ACD) and regulated cell death (RCD). Cell death plays an indispensable role in cerebral ischaemia injury. An increasing number of scholars are exploring the mechanisms and sites of cell death during targeted inhibition of cerebral ischaemia to treat cerebral ischaemia injury. In addition to the established cell death pathways, namely, the apoptosis, pyroptosis and necroptosis pathways, ferroptosis and cuproptosis pathways have been discovered. This article reviews the cell death pathways involved in ischaemic brain injury, discusses the roles played by these death modalities, and suggests therapeutic directions for future targeting of cell death sites.

Nutritional strategies to reduce intestinal cell apoptosis by alleviating oxidative stress

The gut barrier is the first line of defense against harmful substances and pathogens in the intestinal tract. The balance of proliferation and apoptosis of intestinal epithelial cells (IECs) is crucial for maintaining the integrity of the intestinal mucosa and its function. However, oxidative stress and inflammation can cause DNA damage and abnormal apoptosis of the IECs, leading to the disruption of the intestinal epithelial barrier. This, in turn, can directly or indirectly cause various acute and chronic intestinal diseases. In recent years, there has been a growing understanding of the vital role of dietary ingredients in gut health. Studies have shown that certain amino acids, fibers, vitamins, and polyphenols in the diet can protect IECs from excessive apoptosis caused by oxidative stress, and limit intestinal inflammation. This review aims to describe the molecular mechanism of apoptosis and its relationship with intestinal function, and to discuss the modulation of IECs' physiological function, the intestinal epithelial barrier, and gut health by various nutrients. The findings of this review may provide a theoretical basis for the use of nutritional interventions in clinical intestinal disease research and animal production, ultimately leading to improved human and animal intestinal health.

Antitumor Activity of Warbugia ugandensis: Methanolic Extracts and Gene Regulation in Colorectal Cancer

A promising approach to accelerating the development of innovative anti-cancer therapies involves the evaluation of natural plant compounds. In this study, we focused on examining the effects of Warbugia ugandensis (W. ugandensis) methanolic root and stem infusions on the activity of five target genes-COX-2, CASPS-9, Bcl-xL, Bcl2, and 5-LOX-using colorectal cancer (CRC) cell lines (Caco-2). The plant extracts were prepared for testing by dissolving them in dimethyl sulfoxide (DMSO) after undergoing a step-by-step extraction process. Caco-2 cells were then treated with different concentrations of the extracts, and RNA was extracted and purified for analysis. Our results demonstrated a dose-dependent relationship between the phytoconstituents of W. ugandensis and the overexpression of CASP9, along with the downregulation of COX-2, 5-LOX, Bcl-xL, and Bcl2 genes. This suggests that W. ugandensis acts as a potent natural inhibitor of CRC progression. Given the potential clinical benefits, we propose the use of W. ugandensis methanolic root and stem extracts as promising organic inhibitors for CRC tumorigenesis, with more in vitro studies warranted to validate and expand on our findings. Additionally, we recommend further studies to identify and characterize the specific metabolites in W. ugandensis that contribute to the modulation of pathways responsible for inhibiting CRC growth.

Donafenib activates the p53 signaling pathway in hepatocellular carcinoma, induces ferroptosis, and enhances cell apoptosis

Donafenib is an improved version of sorafenib in which deuterium is substituted into the drug's chemical structure, enhancing its stability and antitumor activity. Donafenib exhibits enhanced antitumor activity and better tolerance than sorafenib in preclinical and clinical studies. However, the specific mechanism of its effect on hepatocellular carcinoma has not been reported. Iron deposition is a cell death pattern caused by disturbances in iron metabolism. Apoptosis is a form of programmed cell death. They may interact with each other during cell death. This study mainly explores the potential mechanism of donafenib activating the p53 signaling pathway, inducing iron deposition, and enhancing cell apoptosis in hepatocellular carcinoma. Hepa1-6 and Huh7 cells were treated with various concentrations of donafenib. Scratch healing and pore migration tests were conducted. Analyze apoptosis through flow cytometry and TUNEL fluorescence labeling. RNA sequencing was conducted on both untreated and donafenib-treated Huh7 cells. The key proteins involved in ferroptosis (SLC7A11, GPX4) and apoptosis (caspase3, caspase8, Bax, Bcl-2, p53) were then evaluated using immunoblotting and immunohistochemical staining. Reactive oxygen species (ROS) levels in the cancer cells were measured. Donafenib treatment resulted in a dose-dependent decrease in the proliferation, migration, and invasion capabilities of cancer cells. There was an increase in apoptosis rates and ROS accumulation, and a reduction in tumor volume. The key proteins involved in ferroptosis and apoptosis underwent significant changes. Donafenib activates the p53 signaling pathway, induce ferroptosis, and enhance apoptosis, suggesting its potential as an effective therapeutic agent for HCC.

Advances in structural identification of some thieno[2,3-d]pyrimidine scaffolds as antitumor molecules: Synthetic approaches and control programmed cancer cell death potential

Thieno[2,3-d]pyrimidine fragment is not only bioistostere to quinazoline ring but also to purines which exist in nucleic acids responsible for several key biological processes of the living cells, thus it is of a great interest for many researchers. Thieno[2,3-d]pyrimidine ring has become an important scaffold for different compounds with versatile pharmacological activities including anticancer. These compounds exert their anticancer activity through variant mechanisms of action; one of these is the induction of different programmed cell death types as apoptosis and necroptosis which is an effective approach for cancer treatment. This review highlights the different synthetic approaches of recent thieno[2,3-d]pyrimidine analogs along with their anticancer significance through induction of apoptotic or necroptotic cell death with illustration of the structure-activity relationship (SAR).

Persistence of spike protein at the skull-meninges-brain axis may contribute to the neurological sequelae of COVID-19

SARS-CoV-2 infection is associated with long-lasting neurological symptoms, although the underlying mechanisms remain unclear. Using optical clearing and imaging, we observed the accumulation of SARS-CoV-2 spike protein in the skull-meninges-brain axis of human COVID-19 patients, persisting long after viral clearance. Further, biomarkers of neurodegeneration were elevated in the cerebrospinal fluid from long COVID patients, and proteomic analysis of human skull, meninges, and brain samples revealed dysregulated inflammatory pathways and neurodegeneration-associated changes. Similar distribution patterns of the spike protein were observed in SARS-CoV-2-infected mice. Injection of spike protein alone was sufficient to induce neuroinflammation, proteome changes in the skull-meninges-brain axis, anxiety-like behavior, and exacerbated outcomes in mouse models of stroke and traumatic brain injury. Vaccination reduced but did not eliminate spike protein accumulation after infection in mice. Our findings suggest persistent spike protein at the brain borders may contribute to lasting neurological sequelae of COVID-19.

Irisin in degenerative musculoskeletal diseases: Functions in system and potential in therapy

Degenerative musculoskeletal diseases are a class of diseases related to the gradual structural and functional deterioration of muscles, joints, and bones, including osteoarthritis (OA), osteoporosis (OP), sarcopenia (SP), and intervertebral disc degeneration (IDD). As the proportion of aging people around the world increases, degenerative musculoskeletal diseases not only have a multifaceted impact on patients, but also impose a huge burden on the medical industry in various countries. Therefore, it is crucial to find key regulatory factors and potential therapeutic targets. Recent studies have shown that irisin plays an important role in degenerative musculoskeletal diseases, suggesting that it may become a key molecule in the prevention and treatment of degenerative diseases of the musculoskeletal system. Therefore, this review provides a comprehensive description of the release and basic functions of irisin, and summarizes the role of irisin in OA, OP, SP, and IDD from a cellular and tissue perspective, providing comprehensive basis for clinical application. In addition, we summarized the many roles of irisin as a key information molecule in bone-muscle-adipose crosstalk and a regulatory molecule involved in inflammation, senescence, and cell death, and proposed the interesting possibility of irisin in degenerative musculoskeletal diseases.

STAT3 and the STAT3‑regulated inhibitor of apoptosis protein survivin as potential therapeutic targets in colorectal cancer (Review)

Colorectal cancer (CRC) is one of the leading types of cancer worldwide. CRC development has been associated with the constitutive activation of signal transducer and activator of transcription 3 (STAT3). STAT3 is a master regulator of inflammation during cancer-associated colitis, and becomes upregulated in CRC. In CRC, STAT3 is activated by IL-6, among other pro-inflammatory cytokines, inducing the expression of target genes that stimulate proliferation, angiogenesis and the inhibition of apoptosis. One of the main STAT3-regulated inhibitors of apoptosis is survivin, which is a bifunctional protein that regulates apoptosis and participates in cell mitosis. Survivin expression is normally limited to foetal tissue; however, survivin is also upregulated in tumours. In silico and experimental analyses have shown that the STAT3 interactome is relevant during CRC progression, and the constitutive STAT3-survivin axis participates in development of the tumour microenvironment and response to therapy. The presence of a STAT3-survivin axis has been documented in CRC cohorts, and the expression of these molecules is associated with poor prognosis and a higher mortality rate in patients with CRC. Thus, STAT3, survivin, and the upstream activators IL-6 and IL-6 receptor, are considered therapeutic targets for CRC. Efforts to develop drugs targeting the STAT3-survivin axis include the evaluation of phytochemical compounds, small molecules and monoclonal antibodies. In the present review, the expression, function and participation of the STAT3-survivin axis in the progression of CRC were investigated. In addition, an update on the pre-clinical and clinical trials evaluating potential treatments targeting the STAT3-survivin axis is presented.

Transfection of 12/15-lipoxygenase effectively alleviates inflammatory responses during experimental acute pancreatitis

BACKGROUND

Acute pancreatitis (AP), the initially triggered inflammatory process in the pancreas, can be life-threatening. It has been reported that 15-lipoxygenase may promote the removal of damaged intracellular components, maintain intracellular homeostasis, and promote apoptosis by upregulating the activity of caspases. Despite an increased understanding of the lipoxygenase pathway in inflammation and immune diseases, the role of the Alox15 gene product in modulating the inflammatory changes during AP is not well defined.

AIM

To investigate the effect of Alox15 expression in cerulein-induced AP in rats.

METHODS

Model rats were transfected with Alox15 by injecting a recombinant lentivirus vector encoding Alox15 into the left gastric artery before inducing AP. The expression of Alox15 was then assessed at the mRNA and protein levels.

RESULTS

Our in vivo results showed that serum amylase activity and pancreatic tissue water content were significantly reduced in Alox15-transfected rats. Further, the mRNA expression levels of tumor necrosis factor alpha, interleukin (IL)-1β, IL-6, and monocyte chemoattractant protein-1, as well as the protein expression of nuclear factor kappa B in pancreatic tissue were reduced. Additionally, we observed an upregulation of cleaved caspase-3 that implies an induction of apoptosis in pancreatic cells. The transfection of Alox15 resulted in a lower number of autophagic vacuoles in AP.

CONCLUSION

Our findings demonstrate a regulatory role of Alox15 in apoptosis and autophagy, making it a potential therapeutic target for AP.

Advances in the application of logic gates in nanozymes

Nanozymes are a class of nanomaterials with biocatalytic function and enzyme-like activity, whose advantages include high stability, low cost, and mass production. They can catalyze the substrates of natural enzymes based on specific nanostructures and serve as substitutes for natural enzymes. Their applied research involves a wide range of fields such as biomedicine, environmental governance, agriculture, and food. Molecular logic gates are a new cross-disciplinary discipline, which can simulate the function of silicon circuits on a molecular scale, perform single or multiple input logic operations, and generate logic outputs. A molecular logic gate is a binary operation that converts an input signal into an output signal according to the rules of Boolean logic, generating two signals, a high level, and a low level. The high and low levels represent the "true" and "false" values of the logic gates, and their outputs correspond to "l" and "0" of the molecular logic gates, respectively. The combination of nanozymes and logic gates is a novel and attractive research direction, and the cross-application of the two brings new opportunities and ideas for various fields, such as the construction of efficient biocomputers, intelligent drug delivery systems, and the precise diagnosis of diseases. This review describes the application of logic gates based on nanozymes, which is expected to provide a certain theoretical foundation for researchers' subsequent studies.

Apoptotic and Nonapoptotic Cell Death in Caenorhabditis elegans Development

Programmed cell death (PCD) is an essential component of animal development, and aberrant cell death underlies many disorders. Understanding mechanisms that govern PCD during development can provide insight into cell death programs that are disrupted in disease. Key steps mediating apoptosis, a highly conserved cell death program employing caspase proteases, were first uncovered in the nematode Caenorhabditis elegans, a powerful model system for PCD research. Recent studies in C. elegans also unearthed conserved nonapoptotic caspase-independent cell death programs that function during development. Here, we discuss recent advances in understanding cell death during C. elegans development. We review insights expanding the molecular palette behind the execution of apoptotic and nonapoptotic cell death, as well as new discoveries revealing the mechanistic underpinnings of dying cell engulfment and clearance. A number of open questions are also discussed that will continue to propel the field over the coming years.

Mechanism of Marinobufagenin-Induced Hyperpermeability of Human Brain Microvascular Endothelial Cell Monolayer: A Potential Pathogenesis of Seizure in Preeclampsia

Preeclampsia (preE) is a hypertensive disorder in pregnancies. It is the third leading cause of mortality among pregnant women and fetuses worldwide, and there is much we have yet to learn about its pathophysiology. One complication includes cerebral edema, which causes a breach of the blood-brain barrier (BBB). Urinary marinobufagenin (MBG) is elevated in a preE rat model prior to developing hypertension and proteinuria. We investigated what effect MBG has on the endothelial cell permeability of the BBB. Human brain microvascular endothelial cells (HBMECs) were utilized to examine the permeability caused by MBG. The phosphorylation of ERK1/2, Jnk, p38, and Src was evaluated after the treatment with MBG. Apoptosis was evaluated by examining caspase 3/7. MBG ≥ 1 nM inhibited the proliferation of HBMECs by 46-50%. MBG induced monolayer permeability, causing a decrease in the phosphorylation of ERK1/2 and the activated phosphorylation of Jnk, p38, and Src. MBG increased the caspase 3/7 expression, indicating the activation of apoptosis. Apoptotic signaling or the disruption of endothelia tight junction proteins was not observed when using the p38 inhibitor as a pretreatment in MBG-treated cells. The MBG-induced enhancement of the HBMEC monolayer permeability occurs by the downregulation of ERK1/2, the activation of Jnk, p38, Src, and apoptosis, resulting in the cleavage of tight junction proteins, and are attenuated by p38 inhibition.

Mycoplasma hyopneumoniae inhibits the unfolded protein response to prevent host macrophage apoptosis and M2 polarization

Enzootic pneumonia caused by Mycoplasma hyopneumoniae (M. hyopneumoniae) has inflicted substantial economic losses on the global pig industry. The progression of M. hyopneumoniae induced-pneumonia is associated with lung immune cell infiltration and extensive proinflammatory cytokine secretion. Our previous study established that M. hyopneumoniae disrupts the host unfolded protein response (UPR), a process vital for the survival and immune function of macrophages. In this study, we demonstrated that M. hyopneumoniae targets the UPR- and caspase-12-mediated endoplasmic reticulum (ER)-associated classical intrinsic apoptotic pathway to interfere with host cell apoptosis signaling, thereby preserving the survival of host tracheal epithelial cells (PTECs) and alveolar macrophages (PAMs) during the early stages of infection. Even in the presence of apoptosis inducers, host cells infected with M. hyopneumoniae exhibited an anti-apoptotic potential. Further analyses revealed that M. hyopneumoniae suppresses the three UPR branches and their induced apoptosis. Interestingly, while UPR activation typically drives host macrophages toward an M2 polarization phenotype, M. hyopneumoniae specifically obstructs this process to maintain a proinflammatory phenotype in the host macrophages. Overall, our findings propose that M. hyopneumoniae inhibits the host UPR to sustain macrophage survival and a proinflammatory phenotype, which may be implicated in its pathogenesis in inducing host pneumonia.

ARRB1 inhibits extracellular matrix degradation and apoptosis of nucleus pulposus cells by promoting autophagy and attenuates intervertebral disc degeneration

OBJECTIVE

Intervertebral disc degeneration (IVDD) is the leading cause of lower back pain (LBP). β-arrestin 1 (ARRB1) is a multifunctional protein that regulates numerous pathological processes. The aim of this study was to investigate the role of ARRB1 in IVDD.

METHODS

The expression of ARRB1 in nucleus pulposus (NP) of rats with IVDD was assayed. Next, rat nucleus pulposus cells (NPCs) were infected with lentiviruses containing shArrb1 (LV-shArrb1) and overexpressing Arrb1 (LV-oeArrb1). The roles of Arrb1 in serum-deprived NPCs were investigated by measuring apoptosis, extracellular matrix degradation, and autophagic flux. For experiments in vivo, LV-oeArrb1 lentivirus was injected into the NP tissues of IVDD rats to evaluate the effects of Arrb1 overexpression on NP.

RESULTS

In the NP tissues of IVDD rats, ARRB1 and cleaved caspase-3 expression increased, and the ratio of LC3II/LC3I protein expression was upregulated. Arrb1 knockdown aggravated extracellular matrix degradation, cellular apoptosis, and impairment of autophagic flux in rat NPCs under serum-deprived conditions, whereas Arrb1 overexpression significantly reversed these effects. ARRB1 interacted with Beclin 1, and Arrb1 knockdown suppressed the formation of the Beclin1-PIK3C3 core complex. The autophagy inhibitor 3-methyladenine (3-MA) offset the protective effects of Arrb1 overexpression in serum-deprived NPCs. Furthermore, Arrb1 overexpression inhibited apoptosis and extracellular matrix degradation, promoted autophagy in NP, and delayed the development of IVDD in rats.

CONCLUSION

ARRB1 prevents extracellular matrix degradation and apoptosis of NPCs by upregulating autophagy and ameliorating IVDD progression, presenting an innovative strategy for the treatment of IVDD.

Genetically predicted Caspase 8 levels mediates the causal association between CD4+ T cell and breast cancer

Background

Breast cancer (BC) remains a significant contributor to female mortality globally, with inflammation and the immune system implicated in its pathogenesis. To elucidate potential causal relationships, we evaluated the relationship among 731 immune cell phenotypes and BC be at risk by using Mendelian randomization (MR), while also exploring inflammatory proteins as mediators in this association.

Methods

We obtained immune cell genome-wide association study (GWAS) summary data and 91 inflammatory factors from the GWAS Catalog. BC GWAS data was obtained from the IEU Open GWAS project (ukb-b-16890 for discovery and GCST004988 for validation). We investigated the causal link between immune cells and BC risk by employing a two-sample MR method. Furthermore, we use a two-step MR to quantify the percentage of mediation of immune cell-BC causal effects mediated by inflammatory proteins. To make sure the causal findings were robust, a sensitivity analysis was done.

Results

In both discovery and validation GWAS, a critical inverse correlation between CD4+ T cells and BC risk was found using MR analysis (Discovery: OR, 0.996; P = 0.030. Validation: OR, 0.843; P = 4.09E-07) with Caspase 8 levels mediating 18.9% of the reduced BC risk associated with immune cells(Mediation proportion=a×b/c, Discovery:0.151×-0.005/-0.004 = 18.9%; Validation:0.151×-0.214/-0.171 = 18.9%).

Conclusion

Our study establishes a causal connection linking CD4+ T cells and BC, with Caspase 8 levels partially mediating this relationship. These findings enhance our genetic and molecular comprehension of BC, suggesting potential pathways for future BC immunotherapy drug development.

Exploring apoptotic induction of malabaricone A in triple-negative breast cancer cells: an acylphenol phyto-entity isolated from the fruit rind of Myristica malabarica Lam

Myristica malabarica Lam., commonly known as Malabar nutmeg or false nutmeg, is used in traditional medicine and as a spice. Our exploration focuses on malabaricones, a distinct group of secondary metabolites isolated from the fruit rind of M. malabarica. We investigated the selective cytotoxicity of malabaricones against the triple-negative breast cancer (TNBC) cell line. In particular, malabaricone A (Mal-A) displays heightened toxicity towards TNBC cells (MDA-MB-231), with an IC50 of 8.81 ± 0.03 μM. In vitro fluorimetric assays confirmed the apoptotic capability of Mal-A and its capacity to induce nuclear fragmentation. Additionally, ultrasensitive surface-enhanced Raman spectroscopy confirms DNA fragmentation during cellular apoptosis. Cell cycle analysis indicates arrest during the sub-G0 phase by downregulating key regulatory proteins involved in cell cycle progression. Increased expression levels of caspase 3, 9, and 8 suggest involvement of both extrinsic and intrinsic apoptotic pathways. Finally, assessment of protein expression patterns within apoptotic pathways reveals upregulation of key apoptotic proteins like Fas/FasL, TNF/TNFR1, and p53, coupled with downregulation of several inhibitors of apoptosis proteins such as XIAP, cIAP-2, and Livin. These findings are further verified with in silico molecular docking. Mal-A reveals a strong affinity towards apoptotic proteins, including TNF, Fas, HTRA, Smac, and XIAP, with docking scores ranging from -5.1 to -7.2 kcal mol-1. Subsequently, molecular dynamics simulation confirms the binding stability. This conclusive in vitro evaluation validates Mal-A as a potent phyto-entity against TNBC. To the best of our knowledge, this study represents the first comprehensive anticancer evaluation of Mal-A in TNBC cells.

The time-dependent changes in a mouse model of traumatic brain injury with motor dysfunction

Traumatic brain injury (TBI) results from sudden accidents, leading to brain damage, subsequent organ dysfunction, and potentially death. Despite extensive studies on rodent TBI models, there is still high variability in terms of target points, and this results in significantly different symptoms between models. In this study, we established a more concise and effective TBI mouse model, which included locomotor dysfunctions with increased apoptosis, based on the controlled cortical impact method. Behavioral tests, such as elevated body swing, rotarod, and cylinder tests were performed to assess the validity of our model. To investigate the underlying mechanisms of injury, we analyzed the expression of proteins associated with immune response and the apoptosis signaling pathway via western blotting analysis and immunohistochemistry. Upon TBI induction, the mouse subjects showed motor dysfunctions and asymmetric behavioral assessment. The expression of Bax gradually increased over time and reached its maximum 3 days post-surgery, and then declined. The expression of Mcl-1 showed a similar trend to Bax. Furthermore, the expression of caspase-3, ROCK1, and p53 were highly elevated by 3 days post-surgery and then declined by 7 days post-surgery. Importantly, immunohistochemistry revealed an immediate increase in the level of Bcl-2 at the lesion site upon TBI induction. Also, we found that the expression of neuronal markers, such as NeuN and MAP2, decreased after the surgery. Interestingly, the increase in NFH level was in line with the symptoms of TBI in humans. Collectively, our study demonstrated that the established TBI model induces motor dysfunction, hemorrhaging, infarctions, and apoptosis, closely resembling TBI in humans. Therefore, we predict that our model may be useful for developing effective treatment option for TBI.

Comparative cytotoxicity of Acanthamoeba castellanii-derived conditioned medium on human corneal epithelial and stromal cells

Soluble factors in the secretome of Acanthamoeba castellanii play crucial roles in the pathogenesis of Acanthamoeba keratitis (AK). Investigating the pathological effects of A. castellanii-derived conditioned medium (ACCM) on ocular cells can provide insights into the damage inflicted during AK. This study examined ACCM-induced cytotoxicity in primary human corneal stromal cells (CSCs) and a human SV40 immortalized corneal epithelial cell line (ihCECs) at varying ACCM concentrations (25 %, 50 %, 75 %, and 100 %). MTT, AlamarBlue, Sulforhodamine B, lactate dehydrogenase, and Caspase-3/7 activation assays were used to assess the impact of ACCM on the cell viability, proliferation and apoptosis. Additionally, fluorescent staining was used to reveal actin cytoskeleton changes. ACCM exposure significantly decreased cell viability, increased apoptosis, and disrupted the actin cytoskeleton, particularly at higher concentrations and longer exposures. Proteases were found to mediate these cytopathogenic effects, highlighting the need for characterization of A. castellanii proteases as key virulence factors in AK pathogenesis.

iPSC-induced neurons with the V337M MAPT mutation are selectively vulnerable to caspase-mediated cleavage of tau and apoptotic cell death

BACKGROUND

Tau post-translational modifications (PTMs) result in the gradual build-up of abnormal tau and neuronal degeneration in tauopathies, encompassing variants of frontotemporal lobar degeneration (FTLD) and Alzheimer's disease (AD). Tau proteolytically cleaved by active caspases, including caspase-6, may be neurotoxic and prone to self-aggregation. Also, our recent findings show that caspase-6 truncated tau represents a frequent and understudied aspect of tau pathology in AD in addition to phospho-tau pathology. In AD and Pick's disease, a large percentage of caspase-6 associated cleaved-tau positive neurons lack phospho-tau, suggesting that many vulnerable neurons to tau pathology go undetected when using conventional phospho-tau antibodies and possibly will not respond to phospho-tau based therapies. Therefore, therapeutic strategies against caspase cleaved-tau pathology could be necessary to modulate the extent of tau abnormalities in AD and other tauopathies.

METHODS

To understand the timing and progression of caspase activation, tau cleavage, and neuronal death, we created two mAbs targeting caspase-6 tau cleavage sites and probed postmortem brain tissue from an individual with FTLD due to the V337M MAPT mutation. We then assessed tau cleavage and apoptotic stress response in cortical neurons derived from induced pluripotent stem cells (iPSCs) carrying the FTD-related V337M MAPT mutation. Finally, we evaluated the neuroprotective effects of caspase inhibitors in these iPSC-derived neurons.

RESULTS

FTLD V337M MAPT postmortem brain showed positivity for both cleaved tau mAbs and active caspase-6. Relative to isogenic wild-type MAPT controls, V337M MAPT neurons cultured for 3 months post-differentiation showed a time-dependent increase in pathogenic tau in the form of caspase-cleaved tau, phospho-tau, and higher levels of tau oligomers. Accumulation of toxic tau species in V337M MAPT neurons was correlated with increased vulnerability to pro-apoptotic stress. Notably, this mutation-associated cell death was pharmacologically rescued by the inhibition of effector caspases.

CONCLUSIONS

Our results suggest an upstream, time-dependent accumulation of caspase-6 cleaved tau in V337M MAPT neurons promoting neurotoxicity. These processes can be reversed by caspase inhibition. These results underscore the potential of developing caspase-6 inhibitors as therapeutic agents for FTLD and other tauopathies. Additionally, they highlight the promise of using caspase-cleaved tau as biomarkers for these conditions.

Recent advances in caspase-3, breast cancer, and traditional Chinese medicine: a review

Caspases (cysteinyl aspartate-specific proteinases) are a group of structurally similar proteases in the cytoplasm that can be involved in cell differentiation, programmed death, proliferation, and inflammatory generation. Experts have found that caspase-3 can serve as a terminal splicing enzyme in apoptosis and participate in the mechanism by which cytotoxic drugs kill cancer cells. Breast cancer (BC) has become the most common cancer among women worldwide, posing a severe threat to their lives. Finding new therapeutic targets for BC is the primary task of contemporary physicians. Numerous studies have revealed the close association between caspase-3 expression and BC. Caspase-3 is essential in BC's occurrence, invasion, and metastasis. In addition, Caspase-3 exerts anticancer effects by regulating cell death mechanisms. Traditional Chinese medicine acting through caspase-3 expression is increasingly used in clinical treatment. This review summarizes the biological mechanism of caspase-3 and research progress on BC. It introduces a variety of traditional Chinese medicine related to caspase-3 to provide new ideas for the clinical treatment of BC.

Hepatoprotective potential of taxifolin in type 2 diabetic rats: modulation of oxidative stress and Bcl2/Bax/Caspase-3 signaling pathway

BACKGROUND

Diabetes mellitus (DM) is a global metabolic problem. Several factors including hyperglycemia, oxidative stress, and inflammation play significant roles in the development of DM complications. Apoptosis is also an essential event in DM pathophysiology, -with B-cell lymphoma 2 (Bcl-2) and Bcl-2 associated X (Bax) determining apoptotic susceptibility. The present study aimed to elucidate the protective effects of two doses of taxifolin (TXF) on liver damage in diabetic rats and explore the possible mechanisms of action.

METHODS AND RESULTS

DM was induced in eighteen rats through intraperitoneal injections of 50 mg/kg streptozotocin and 110 mg/kg nicotinamide. Diabetic rats received daily oral intubation of 25 and 50 mg/kg TXF for 3 months. In the untreated diabetic group, there was a significant increase in fasting and postprandial glucose levels, glycosylated hemoglobin A1C (HbA1c), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6), while insulin and adiponectin levels decreased significantly. Both TXF doses mitigated hyperglycemia, regulated cytokine production, and increased insulin level. Gene expressions and protein levels of Bax, caspase 3, and cytochrome c were significantly increased, while Bcl-2 was significantly decreased in the livers of diabetic rats, effects that were significantly ameliorated after TXF treatment. The results of the TUNEL assay supported the apoptotic pathway. Additionally, TXF significantly decreased lipid peroxidation and enhanced antioxidant enzyme activity in diabetic rats. Liver enzymes and histopathological changes also showed improvement.

CONCLUSIONS

TXF mitigated diabetes-associated hepatic damage by reducing hyperglycemia, oxidative stress, inflammation, and modulating anti-/pro-apoptotic genes and proteins. A dose of 50 mg/kg TXF was more effective than 25 mg/kg and is recommended for consumption.

Medicinal herbal remedies in neurodegenerative diseases: an update on antioxidant potential

It has been widely documented that medicinal herbal remedies are effective, have fewer side effects than conventional medicine, and have a synergistic effect on health collaborations in the fight against complicated diseases. Traditional treatments for neurological problems in ancient times sometimes involved the use of herbal remedies and conventional methods from East Asian countries including India, Japan, China, and Korea. We collected and reviewed studies on plant-derived neuroprotective drugs and tested them in neurotoxic models. Basic research, preclinical and clinical transgene research can benefit from in silico, in vitro, and in vivo investigations. Research, summaries of the extracts, fractions, and herbal ingredients were compiled from popular scientific databases, which were then examined according to origin and bioactivity. Given the complex and varied causes of neurodegeneration, it may be beneficial to focus on multiple mechanisms of action and a neuroprotection approach. This approach aims to prevent cell death and restore function to damaged neurons, offering promising strategies for preventing and treating neurodegenerative diseases. Neurodegenerative illnesses can potentially be treated with natural compounds that have been identified as neuroprotective agents. To gain deeper insights into the neuropharmacological mechanisms underlying the neuroprotective and therapeutic properties of naturally occurring antioxidant phytochemical compounds in diverse neurodegenerative diseases, this study aims to comprehensively review such compounds, focusing on their modulation of apoptotic markers such as caspase, Bax, Bcl-2, and proinflammatory markers. In addition, we delve into a range of efficacies of antioxidant phytochemical compounds as neuroprotective agents in animal models. They reduce the oxidative stress of the brain and have been shown to have anti-apoptotic effects. Many researches have demonstrated that plant extracts or bioactive compounds can fight neurodegenerative disorders. Herbal medications may offer neurodegenerative disease patients' new treatments. This may be a cheaper and more culturally appropriate alternative to standard drugs for millions of people with age-related NDDs.

ARTS and small-molecule ARTS mimetics upregulate p53 levels by promoting the degradation of XIAP

Mutations resulting in decreased activity of p53 tumor suppressor protein promote tumorigenesis. P53 protein levels are tightly regulated through the Ubiquitin Proteasome System (UPS). Several E3 ligases were shown to regulate p53 stability, including MDM2. Here we report that the ubiquitin E3 ligase XIAP (X-linked Inhibitors of Apoptosis) is a direct ligase for p53 and describe a novel approach for modulating the levels of p53 by targeting the XIAP pathway. Using in vivo (live-cell) and in vitro (cell-free reconstituted system) ubiquitylation assays, we show that the XIAP-antagonist ARTS regulates the levels of p53 by promoting the degradation of XIAP. XIAP directly binds and ubiquitylates p53. In apoptotic cells, ARTS inhibits the ubiquitylation of p53 by antagonizing XIAP. XIAP knockout MEFs express higher p53 protein levels compared to wild-type MEFs. Computational screen for small molecules with high affinity to the ARTS-binding site within XIAP identified a small-molecule ARTS-mimetic, B3. This compound stimulates apoptosis in a wide range of cancer cells but not normal PBMC (Peripheral Blood Mononuclear Cells). Like ARTS, the B3 compound binds to XIAP and promotes its degradation via the UPS. B3 binding to XIAP stabilizes p53 by disrupting its interaction with XIAP. These results reveal a novel mechanism by which ARTS and p53 regulate each other through an amplification loop to promote apoptosis. Finally, these data suggest that targeting the ARTS binding pocket in XIAP can be used to increase p53 levels as a new strategy for developing anti-cancer therapeutics.

Reconstruction of TNF-α with specific isoelectric point released from SPIONs basing on variable charge to enhance pH-sensitive controlled-release

The clinical application of tumor necrosis factor-α (TNF-α) is limited by its short half-life, subeffective concentration in the targeted area and severe systemic toxicity. In this study, the recombinant polypeptide S4-TNF-α was constructed and coupled with chitosan-modified superparamagnetic iron oxide nanoparticles (S4-TNF-α-SPIONs) to achieve pH-sensitive controlled release and active tumor targeting activity. The isoelectric point (pI) of S4-TNF-α was reconstructed to approach the pH of the tumor microenvironment. The negative-charge S4-TNF-α was adsorbed to chitosan-modified superparamagnetic iron oxide nanoparticles (CS-SPIONs) with a positive charge through electrostatic adsorption at physiological pH. The acidic tumor microenvironment endowed S4-TNF-α with a zero charge, which accelerated S4-TNF-α release from CS-SPIONs. Our studies showed that S4-TNF-α-SPIONs displayed an ideal pH-sensitive controlled release capacity and improved antitumor effects. Our study presents a novel approach to enhance the pH-sensitive controlled-release of genetically engineered drugs by adjusting their pI to match the pH of the tumor microenvironment.

Irisin as an agent for protecting against osteoporosis: A review of the current mechanisms and pathways

BACKGROUND

Osteoporosis is recognized as a skeletal disorder characterized by diminished bone tissue quality and density. Regular physical exercise is widely acknowledged to preserve and enhance bone health, but the detailed molecular mechanisms involved remain unclear. Irisin, a factor derived from muscle during exercise, influences bone and muscle. Since its discovery in 2012, irisin has been found to promote bone growth and reduce bone resorption, establishing a tangible link between muscle exertion and bone health. Consequently, the mechanism by which irisin prevents osteoporosis have attracted significant scientific interest.

AIM OF THE REVIEW

This study aims to elucidate the multifaceted relationship between exercise, irisin, and bone health. Focusing on irisin, a muscle-derived factor released during exercise, we seek to understand its role in promoting bone growth and inhibiting resorption. Through a review of current research article on irisin in osteoporosis, Our review provides a deep dive into existing research on influence of irisin in osteoporosis, exploring its interaction with pivotal signaling pathways and its impact on various cell death mechanisms and inflammation. We aim to uncover the molecular underpinnings of how irisin, secreted during exercise, can serve as a therapeutic strategy for osteoporosis.

KEY SCIENTIFIC CONCEPTS OF THE REVIEW

Irisin, secreted during exercise, plays a vital role in bridging muscle function to bone health. It not only promotes bone growth but also inhibits bone resorption. Specifically, Irisin fosters osteoblast proliferation, differentiation, and mineralization predominantly through the ERK, p38, and AMPK signaling pathways. Concurrently, it regulates osteoclast differentiation and maturation via the JNK, Wnt/β-catenin and RANKL/RANK/OPG signaling pathways. This review further delves into the profound significance of irisin in osteoporosis and its involvement in diverse cellular death mechanisms, including apoptosis, autophagy, ferroptosis, and pyroptosis.

N6-Methyladenosine Methylation of mRNA in Cell Apoptosis

Apoptosis, a highly controlled homeostatic mechanism that eliminates single cells without destroying tissue function, occurs during growing development and senescence. N6-methyladenosine (m6A), as the most common internal modification of eukaryotic mRNA, fine-tunes gene expression by regulating many aspects of mRNA metabolism, such as splicing, nucleation, stability, translation, and degradation. Remarkably, recent reports have indicated that aberrant methylation of m6A-related RNA may directly or indirectly influence the expression of apoptosis-related genes, thus regulating the process of cell apoptosis. In this review, we summarized the relationship between m6A modification and cell apoptosis, especially its role in the nervous system, and analyzed the limitations of the current research.

Zosterabisphenone B, a new diarylheptanoid heterodimer from the seagrass Zostera marina, induces apoptosis cell death in colon cancer cells and reduces tumour growth in mice

Colorectal cancer (CRC) is one of the most common malignant tumours worldwide. Diarylheptanoids, secondary metabolites isolated from Zostera marina, are of interest in natural products research due to their biological activities. Zosterabisphenone B (ZBP B) has recently been shown to inhibit the viability of CRC cells. The aim of this study was to investigate the therapeutic potential of ZBP B for targeting human CRC cells. Cell viability was determined using the MTT assay. Flow cytometry and Western blot analyses were used to assess apoptosis and autophagy. A CRC xenograft model was used to evaluate the in vivo effect of ZBP B. No cytotoxic effect on HCEC cells was observed in the in vitro experiments. ZBP B caused morphological changes in HCT116 colon cancer cells due to an increase in early and late apoptotic cell populations. Mechanistically, ZBP B led to an increase in cleaved caspase-3, caspase-8, caspase-9, PARP and BID proteins and a decrease in Bcl-2 and c-Myc proteins. In the xenograft model of CRC, ZBP B led to a reduction in tumour growth. These results indicate that ZBP B exerts a selective cytotoxic effect on CRC cells by affecting apoptotic signalling pathways and reducing tumour growth in mice. Taken together, our results suggest that ZBP B could be a lead compound for the synthesis and development of CRC drugs.

Identification and function analysis of BCL2 in immune response of Pteria penguin

B-cell lymphoma/leukemia-2 (BCL2), an anti-apoptotic factor in the mitochondrial regulatory pathway of apoptosis, is critically important in immune defenses. In this study, a novel BCL2 gene was characterized from Pteria penguin (P. penguin). The PpBCL2 was 1482 bp long, containing an open reading frame (ORF) of 588 bp encoding 195 amino acids. Four highly conserved BCL-2 homology (BH) domains were found in PpBCL2. Amino acid alignment and phylogenetic tree showed that PpBCL2 had the highest similarity with BCL2 of Crassostrea gigas at 65.24 %. Tissue expression analysis showed that PpBCL2 had high constitutive expression in gill, digestive diverticulum and mantle, and was significantly increased 72 h of Vibrio parahaemolyticus (V. parahaemolyticus) challenge in these immune tissues. Furthermore, PpBCL2 silencing significantly inhibited antimicrobial activity of hemolymph supernatant by 1.4-fold, and significantly reduced the survival rate by 51.7 % at 72 h post infection in P. penguin. These data indicated that PpBCL2 played an important role in immune response of P. penguin against V. parahaemolyticus infection.

Ephrin B2 (EFNB2) potentially protects against intervertebral disc degeneration through inhibiting nucleus pulposus cell apoptosis

Nucleus pulposus (NP) cell apoptosis is a significant indication of accelerated intervertebral disc degeneration; however, the precise mechanism is unelucidated as of yet. Ephrin B2 (EFNB2), the only gene down-regulated in the three degraded intervertebral disc tissue microarray groups (GSE70362, GSE147383 and GSE56081), was screened for examination in this study. Subsequently, EFNB2 was verified to be down-regulated in degraded NP tissue samples. Interleukin-1 (IL-1β) treatment of NP cells to simulate the IDD environment indicated that IL-1β treatment decreased EFNB2 expression. In degenerative NP cells stimulated by IL-1β, EFNB2 knockdown significantly increased the rate of apoptosis as well as the apoptosis-related molecules cleaved-caspase-3 and the Bax to Bcl-2 ratio. EFNB2 was found to promote AKT, PI3K, and mTOR phosphorylation; the PI3K/AKT signaling role was investigated using the PI3K inhibitor LY294002. EFNB2 overexpression significantly increased PI3K/AKT pathway activity in IL-1β-stimulated NP cells than the normal control. Moreover, EFNB2 partially alleviated NP cell apoptosis induced by IL-1β, reduced the cleaved-cas3 level, and decreased the Bax/Bcl-2 ratio after the addition of the inhibitor LY294002. Additionally, EFNB2 overexpression inhibited the ERK1/2 phosphorylation; the effects of EFNB2 overexpression on ERK1/2 phosphorylation, degenerative NP cell viability, and cell apoptosis were partially reversed by ERK signaling activator Ceramide C6. EFNB2 comprehensively inhibited the apoptosis of NP cells by activating the PI3K/AKT signaling and inhibiting the ERK signaling, obviating the exacerbation of IDD. EFNB2 could be a potential target to protect against degenerative disc changes.

The Effect of κ-Carrageenan on Porcine Sperm Cryo-Survival

κ-Carrageenan is a sulfated polysaccharide from red seaweed with substantial antioxidant activities. This study aimed to investigate the effect of κ-Carrageenan treatment on frozen-thawed (FT) porcine semen quality. Therefore, the spermatozoa were diluted and cryopreserved in a freezing extender supplemented with 0 (control), 0.2, 0.4, 0.6, and 0.8 mg/mL κ-Carrageenan. Sperm kinematics were assessed immediately after thawing (AT) and post-incubation for 120 min. The viability, acrosome integrity, lipid peroxidation, mitochondrial membrane potential (MMP), and intracellular caspase activity were measured AT. The results indicated that 0.2 mg/mL κ-Carrageenan increased total and progressive motility AT and post-incubation for 120 min (p < 0.05). Moreover, the viable sperm percentage and MMP after 0.2 mg/mL treatment were higher than those after control and other κ-Carrageenan concentration treatments. The proportion of acrosome-intact spermatozoa was significantly higher after 0.2 and 0.4 mg/mL κ-Carrageenan treatment than that after control and other κ-Carrageenan concentration treatments. The intracellular caspase activity was not significantly different among the experimental groups. However, the MDA concentration after 0.2 mg/mL κ-Carrageenan treatment was lower (p < 0.05) than that after the control treatment. Taken together, adding κ-Carrageenan to the porcine semen freezing extender improved the FT sperm quality mainly by influencing membrane stability and protecting against oxidative stress.

Toxic effects of the insecticide tolfenpyrad on zebrafish embryos: Cardiac toxicity and mitochondrial damage

Tolfenpyrad, a highly effective and broad-spectrum insecticide and acaricide extensively utilized in agriculture, presents a potential hazard to nontarget organisms. This study was designed to explore the toxic mechanisms of tolfenpyrad on zebrafish embryos. Between 24 and 96 h after exposure of the fertilized embryos to tolfenpyrad at concentrations ranging from 0.001 to 0.016 mg/L (96 h-LC50 = 0.017 mg/L), lethal effects were apparent, accompanied with notable anomalies including pericardial edema, increased pericardial area, diminished heart rate, and an elongated distance between the venous sinus and the arterial bulb. Tolfenpyrad elicited noteworthy alterations in the expression of genes pertinent to cardiac development and apoptosis, with the most pronounced changes observed in the cardiac development-related genes of bone morphogenetic protein 2b (bmp2b) and p53 upregulated modulator of apoptosis (puma). The findings underscore that tolfenpyrad induces severe cardiac toxicity and mitochondrial damage in zebrafish embryos. This data is imperative for a comprehensive assessment of tolfenpyrad risks to aquatic ecosystems, particularly considering the limited knowledge regarding its detrimental impact on aquatic vertebrates.