Mitochondrial Pathway Research Articles

The Effects of Crude Alkaloid Extracts of Convolutes Arvensis on Tumour Cell Lines and Their Potential For Toxicity

General Background: Cancer remains a leading cause of mortality worldwide, and the search for effective treatments continues to intensify. Specific Background: Convolvulus arvensis has been traditionally used for medicinal purposes, but its potential as an anticancer agent is underexplored. Knowledge Gap: The cytotoxic and apoptotic mechanisms of crude alkaloids extracted from C. arvensis against specific cancer cell lines have not been fully characterized. Aims: This study investigates the antioxidant activity and cytotoxic effects of C. arvensis crude alkaloids on mouse liver cancer (HC) and human breast cancer (AMJ13) cell lines, focusing on apoptosis-related gene expression. Results: The antioxidant activity of C. arvensis was comparable to that of ascorbic acid, with inhibition rates of 92.01% at 500 µg/ml. Crude alkaloids demonstrated dose-dependent cytotoxicity, with a maximum inhibition rate of 82.65% in AMJ13 cells and 79.49% in HC cells at 500 µg/ml. Gene expression analysis revealed upregulation of caspase-9, indicating apoptosis via the intrinsic mitochondrial pathway. Novelty: This study is among the first to provide molecular evidence of C. arvensis-induced apoptosis through the intrinsic pathway, offering a novel insight into its anticancer potential. Implications: These findings suggest that C. arvensis alkaloids could be developed as a therapeutic option for cancer treatment, with future studies needed to isolate specific compounds and assess their in vivo efficacy. Highlights: C. arvensis alkaloids show antioxidant activity similar to ascorbic acid. Alkaloids inhibit liver and breast cancer cell growth dose-dependently. Apoptosis triggered via caspase-9 through the mitochondrial pathway. Keywords: Convolvulus arvensis, alkaloids, cancer, apoptosis, antioxidant

The Integrated Stress Response Suppresses PINK1-dependent Mitophagy by Preserving Mitochondrial Import Efficiency.

Mitophagy is crucial for maintaining mitochondrial health, but how its levels adjust to different stress conditions remains unclear. In this study, we investigated the role of the DELE1-HRI axis of integrated stress response (ISR) in regulating mitophagy, a key mitochondrial stress pathway. Our findings show that the ISR suppresses mitophagy under non-depolarizing mitochondrial stress by positively regulating mitochondrial protein import, independent of ATF4 activation. Mitochondrial protein import is regulated by the rate of protein synthesis under both depolarizing and non-depolarizing stress. Without ISR, increased protein synthesis overwhelms the mitochondrial import machinery, reducing its efficiency. Under depolarizing stress, mitochondrial import is heavily impaired even with active ISR, leading to significant PINK1 accumulation. In contrast, non-depolarizing stress allows more efficient protein import in the presence of ISR, resulting in lower mitophagy. Without ISR, mitochondrial protein import becomes severely compromised, causing PINK1 accumulation to reach the threshold necessary to trigger mitophagy. These findings reveal a novel link between ISR-regulated protein synthesis, mitochondrial import, and mitophagy, offering potential therapeutic targets for diseases associated with mitochondrial dysfunction.

1-Deoxynojirimycin Derivative Containing Tegafur Induced HCT-116 Cell Apoptosis through Mitochondrial Dysfunction and Oxidative Stress Pathway

1-Deoxynojirimycin Derivative Containing Tegafur Induced HCT-116 Cell Apoptosis through Mitochondrial Dysfunction and Oxidative Stress Pathway

How Do ROS Induce NETosis? Oxidative DNA Damage, DNA Repair, and Chromatin Decondensation.

Neutrophil extracellular traps (NETs) are intricate, DNA-based, web-like structures adorned with cytotoxic proteins. They play a crucial role in antimicrobial defense but are also implicated in autoimmune diseases and tissue injury. The process of NET formation, known as NETosis, is a regulated cell death mechanism that involves the release of these structures and is unique to neutrophils. NETosis is heavily dependent on the production of reactive oxygen species (ROS), which can be generated either through NADPH oxidase (NOX) or mitochondrial pathways, leading to NOX-dependent or NOX-independent NETosis, respectively. Recent research has revealed an intricate interplay between ROS production, DNA repair, and NET formation in different contexts. UV radiation can trigger a combined process of NETosis and apoptosis, known as apoNETosis, driven by mitochondrial ROS and DNA repair. Similarly, in calcium ionophore-induced NETosis, both ROS and DNA repair are key components, but only play a partial role. In the case of bacterial infections, the early stages of DNA repair are pivotal. Interestingly, in serum-free conditions, spontaneous NETosis occurs through NOX-derived ROS, with early-stage DNA repair inhibition halting the process, while late-stage inhibition increases it. The intricate balance between DNA repair processes and ROS production appears to be a critical factor in regulating NET formation, with different pathways being activated depending on the nature of the stimulus. These findings not only deepen our understanding of the mechanisms behind NETosis but also suggest potential therapeutic targets for conditions where NETs contribute to disease pathology.

The Toxoplasma gondii mitochondrial transporter ABCB7L is essential for the biogenesis of cytosolic and nuclear iron-sulfur cluster proteins and cytosolic translation.

Iron-sulfur (Fe-S) clusters are inorganic cofactors of proteins that play key roles in numerous essential biological processes, for example, respiration and DNA replication. Cells possess dedicated biosynthetic pathways to assemble Fe-S clusters, including a pathway in the mitochondrion and cytosol. A single transporter, called ABCB7, connects these two pathways, allowing an essential intermediate generated by the mitochondrial pathway to be used in the cytosolic pathway. Cytosolic and nuclear Fe-S proteins are dependent on the mitochondrial pathway, mediated by ABCB7, in numerous organisms studied to date. Here, we study the role of a homolog of ABCB7, which we name ABCB7-like (ABCB7L), in the ubiquitous unicellular apicomplexan parasite Toxoplasma gondii. We generated a depletion mutant of Toxoplasma ABCB7L and showed its importance for parasite fitness. Using comparative quantitative proteomic analysis and experimental validation of the mutants, we show that ABCB7L is required for cytosolic and nuclear, but not mitochondrial, Fe-S protein biogenesis. Our study supports the conservation of a protein homologous to ABCB7 and which has a similar function in apicomplexan parasites and provides insight into an understudied aspect of parasite metabolism.

Ultraviolet radiation inhibits mitochondrial bioenergetics activity.

Mitochondria play an important role in cellular function, not only as a major site of adenosine triphosphate (ATP) production but also by regulating energy expenditure, apoptosis signaling, control of the cell cycle, cellular growth, cell differentiation, transportation of metabolites, and production of reactive oxygen species. Interaction with electromagnetic waves can lead to dysregulation or alterations in the patterns of energy activities in the mitochondria. Ultraviolet light (UV) can be found in sunlight and artificial sources, such as lamps. UV radiation can cause damage to DNA, proteins, and lipids. Besides that, UV radiation is largely used in microorganism disinfection. To establish possible alterations in mitochondrial bioenergetics, this study proposes to investigate the UV (at two distinct intervals) effects on isolated mitochondria from mice liver to obtain direct responses and selective permeability of the internal membrane information. UVA-371 and UVC-255 nm lamps were used to irradiate, at different doses varying from 22.5 to 756 mJ/cm2, isolated mitochondria samples. Mitochondrial respiration pathways were investigated by high-resolution respirometry, and possible mitochondrial membrane damages were evaluated by mitochondrial swelling by spectrophotometer analysis. UVC irradiation results (in the higher dose) indicate decrease in 75% of mitochondrial bioenergetics capacity, such as limitation of oxidative phosphorylation in 60% and increased energy dissipation in 30%. Mitochondrial swelling experiments (spectrophotometer) indicated inner membrane damage, and consequently a loss of selective permeability. Direct correlation between irradiation and effect responses was observed, mitochondrial bioenergetics is severely affected by UVC radiation, but (UVA) radiation did not present bioenergetic alterations. These alterations can contribute to improving the knowledge behind the cell death mechanism in disinfection UV light and UV therapy such as phototherapy.

Alternative oxidase affects ascorbate metabolism in Arabidopsis thaliana plants under high-light conditions: possible links between respiratory electron transport pathways in mitochondria

Alternative oxidase affects ascorbate metabolism in Arabidopsis thaliana plants under high-light conditions: possible links between respiratory electron transport pathways in mitochondria

Phytochemical composition and anticancer effect of Akebia trifoliata seed in non-small cell lung cancer A549 cells

BackgroundAkebia trifoliata is a widely distributed medicine and food homology plant. Its fruit is used to treat tumors and the seed’s weight proportion exceeds 50%. However, the anti-tumor effect of A. trifoliata seed remains poorly studied. MethodsUHPLC-Q-Orbitrap-MS was used to identify the chemical components of A. trifoliata seed water extract (WE) and ethanolic extract (EE), and their cytotoxicity was evaluated using MTT assay. Further, colony formation and cell cycle assays examined the anti-proliferative effect of A. trifoliata seed EE. Next, morphology observation, AO/EB staining, Hoechst 33,258 staining, Annexin V-PE/7-AAD staining, and JC-1 assays were employed to detect apoptosis. The influence of A. trifoliata seed EE on A549 cell metastasis was assessed by wound healing and transwell invasion tests. In addition, western blotting and network pharmacology were applied to further analyze its anticancer mechanism. ResultsEighty-two components were characterized from the A. trifoliata seed WE and EE. For anticancer activity, A. trifoliata seed EE exhibited high cytotoxicity against cancer cells A549 (IC50: 52.38 ± 1.04 μg/mL) and NCI-H1299 (IC50: 70.29 ± 0.58 μg/mL) and revealed low cytotoxicity against non-cancer cells MRC-5 (IC50: 101.28 ± 2.84 μg/mL) and L929 (IC50: 113.44 ± 0.55 μg/mL). A. trifoliata seed EE suppressed A549 cell proliferation by inducing S-phase arrest via down-regulation of CDK2 and p21 as well as up-regulation of cyclin E1 and E2. It increased the Bax/Bcl-2 ratio, reduced mitochondrial membrane potential (ΔΨm), activated caspase-9 and caspase-3, cleaved PARP, and triggered apoptosis through the mitochondrial pathway. Besides, it repressed migratory and invasive ability by reducing MMP-2, MMP-9, and N-cadherin levels. ConclusionA. trifoliata seed EE exhibits outstanding anticancer properties and has the exploitation potential as an anticancer drug in the pharmaceutical industry.

Luteolin (LUT) Induces Apoptosis and Regulates Mitochondrial Membrane Potential to Inhibit Cell Growth in Human Cervical Epidermoid Carcinoma Cells (Ca Ski).

Background/Objectives: Luteolin (LUT) is a natural flavonoid with known anti-inflammatory, antioxidant, and anti-cancer properties. Cervical cancer, particularly prevalent in certain regions, remains a significant health challenge due to its high recurrence and poor response to treatment. This study aimed to investigate the anti-tumor effects of LUT on human cervical epidermoid carcinoma cells (Ca Ski), focusing on cell growth inhibition, apoptosis induction, and regulation of mitochondrial membrane potential. Methods: Ca Ski cells were treated with varying concentrations of LUT (0, 25, 50, 100 µM) for different time periods (24, 48, 72 hours). Cell viability was measured using the MTT assay, apoptosis was assessed by flow cytometry with annexin V-FITC/PI staining, and changes in mitochondrial membrane potential were evaluated using JC-1 staining. Caspase-3 activation was examined by flow cytometry, and expression of apoptosis-related proteins (caspase-3, -8, -9, AIF) was analyzed via Western blotting. Results: LUT significantly inhibited the growth of Ca Ski cells in a dose- and time-dependent manner, with the most pronounced effects observed at 100 µM over 72 hours. Flow cytometry confirmed that LUT induced apoptosis without causing necrosis. Mitochondrial membrane potential was reduced after LUT treatment, coinciding with increased caspase-3 activation. Western blot analysis revealed the upregulation of pro-apoptotic proteins caspase-3, -8, -9, and AIF, indicating that LUT induces apoptosis through the intrinsic mitochondrial pathway. Conclusions: Luteolin effectively inhibits cervical cancer cell proliferation and induces apoptosis by disrupting mitochondrial membrane potential and activating caspases. These findings suggest that LUT holds potential as a therapeutic agent for cervical cancer, with further studies needed to explore its in vivo efficacy and broader clinical applications.

Dendrosomal Curcumin Showed Cytotoxic Effects on Breast Cancer Cell Line by Inducing Mitochondrial Apoptosis Pathway and Cell Division Arrest

Background: Mutations in the p53 gene have been linked to the initiation and progression of breast cancer, as well as resistance to chemotherapy. Therefore, the development of novel treatment approaches is essential to combat this disease. Objectives: This study aimed to evaluate the effects of dendrosomal curcumin (DNC) on the breast cancer cell line MDA-MB231. Methods: MDA-MB231 cells were treated with 20 μM DNC, and the apoptosis rate and cell proliferation cycles were assessed using flow cytometry. Additionally, after RNA extraction and cDNA synthesis, the expression levels of Lnc-DANCR, EZH2, Noxa, bcl-2, bax, PUMA, p21, and p53 genes were analyzed using RT-PCR. Protein expression levels of P53, P21, Bcl-2, and Bax were evaluated through western blotting. Results: Dendrosomal curcumin induced apoptosis in MDA-MB231 cells and caused cell cycle arrest at the SubG1 phase. Dendrosomal curcumin treatment downregulated Lnc-DANCR, EZH2, bcl-2, and p53 gene expression, while upregulating bax, Noxa, PUMA, and p21 gene expression in a time-dependent manner. Bax and P21 protein levels were significantly upregulated following DNC treatment, whereas Bcl-2 and P53 protein levels were downregulated in DNC-treated breast cancer cells. Conclusions: In summary, dendrosomal nanocurcumin demonstrated potent anti-tumor effects against breast cancer cells, suggesting its potential as a therapeutic agent in breast cancer treatment.

Icariin promotes skeletal muscle mitochondrial biogenesis by the AMPK-PPARδ-PGC-1α signaling pathway: A potential mechanism for beneficial muscle function homeostasis

Mitochondrial biogenesis is a key factor in regulating skeletal muscle function and homeostasis. At present, a growing number of natural polyphenols, flavonoids and other compounds have been reported to have the function of regulating skeletal muscle oxidative metabolism. Here, we aimed to explore the effect of the flavonoid compound icariin purified from Epimedium koreanum Nakai in regulating mitochondrial biogenesis in mice and C2C12 myotubes. We found that icariin elevated the inverted suspension time by 1.72-fold and the distance run on the treadmill by 1.52-fold in mice. Daytime respiratory exchange ratio was significantly lower in mice after 8 weeks of icariin treatment compared to control groups. Icariin activated the mitochondrial biogenetic signaling pathway and mitochondrial marker expression, and the mitochondrial size of gastrocnemius and soleus was increased by 2.3-fold and 2.0-fold in mice, respectively. In addition, icariin elevated mitochondrial DNA copy number by 1.41-fold and 1.54-fold in gastrocnemius and C2C12 myotube cells, respectively. In vitro studies showed that inhibition of p-AMPK and PPARδ could attenuate ICA-regulated mitochondrial biogenetic pathway. Our study suggests that icariin promotes mitochondrial biogenesis and exercise endurance through AMPK-PPARδ-PGC-1α signaling pathway in C57BL/6 J mice skeletal muscle, indicating that icariin may be able to regulate muscle mitochondria function as an exercise mimetic.

MPV17 Prevents Myocardial Ferroptosis and Ischemic Cardiac Injury through Maintaining SLC25A10-Mediated Mitochondrial Glutathione Import.

Ferroptosis is a recently identified iron-dependent programmed cell death with lipid peroxide accumulation and condensation and compaction of mitochondria. A recent study indicated that ferroptosis plays a pivotal role in ischemic cardiac injury with the mechanisms remain largely unknown. This study demonstrates that when an iron overload occurs in the ischemia/reperfusion cardiac tissues, which initiates myocardial ferroptosis, the expression levels of mitochondrial inner membrane protein MPV17 are reduced. Overexpression of MPV17 delivered via adenovirus significantly reduced ferroptosis in both cardiomyocytes with high levels of iron and cardiac I/R tissues. Mitochondrial glutathione (mtGSH), crucial for reactive oxygen species scavenging and mitochondrial homeostasis maintenance, is depleted in myocardial ferroptosis caused by iron overload. This mechanistic study shows that MPV17 can increase mitochondrial glutathione levels through maintaining the protein homeostasis of SLC25A10, which is a mitochondrial inner-membrane glutathione transporter. The absence of MPV17 in iron overload resulted in the ubiquitination-dependent degradation of SLC25A10, leading to impaired mitochondrial glutathione import. Moreover, we found that MPV17 was the targeted gene of Nrf2, which plays a pivotal role in preventing lipid peroxide accumulation and ferroptosis. The decreased expression levels of Nrf2 led to the inactivation of MPV17 in iron overload-induced myocardial ferroptosis. In summary, this study demonstrates the critical role of MPV17 in protecting cardiomyocytes from ferroptosis and elucidates the Nrf2-MPV17-SLC25A10/mitochondrial glutathione signaling pathway in the regulation of myocardial ferroptosis.

A Dual Action Platinum(IV) Complex with Self-assembly Property Inhibits Prostate Cancer through Mitochondrial Stress Pathway.

Platinum(IV) prodrugs are highly promising anticancer agents because they can selectively target tumors and minimize the adverse effects associated with their PtII congeners. In this study, we synthesized dual action PtIV complexes by linking oxoplatin with lithocholic acid. The synthesized compounds, designated as PL-I, PL-II, and PL-III, can spontaneously self-assemble in water, resulting in the formation of spherical shape nanoparticles. Among the developed complexes, PL-III appeared to be the most potent compound against all the tested cancer cell lines, with 10 fold higher cytotoxicity compared to cisplatin in PC3 cells. The complex arrests the cell cycle in the S and G2 phases and induces DNA damage. Additional mechanistic investigations demonstrate that PL-III predominantly localizes within the mitochondria and cytoplasm. Consequently, PL-III disrupts mitochondrial membrane potential, increases ROS production, and perturbs mitochondrial bioenergetics in PC3 cells. The complex induces apoptosis through the mitochondrial pathway by upregulating pro-apoptotic protein expression and downregulating anti-apoptotic protein expression from the BCl-2 protein family. These results demonstrate that higher cellular uptake and reduction of PL-III by biological reductants in PC3 cells resulted in a synergistic effect of lithocholic acid and cisplatin, which can be easily observed due to its unique cytotoxic mechanism. This further underscores the significance of dual-action PtIV complexes in enhancing the efficacy of cancer therapy.

Deferasirox's Anti-Chemoresistance and Anti-Metastatic Effect on Non-Small Cell Lung Carcinoma.

Clinically approved iron chelators, originally designed to address iron overload disorders, have emerged as potential anticancer agents. Deferasirox (Def), a tridentate iron chelator, has demonstrated antiproliferative effects in cancer. Background/Objectives: This study aims to elucidate the mechanism of action of Def and its impact on non-small cell lung carcinoma (NSCLC). Methods: NSCLC A549 cells were treated with Def to assess cytotoxicity, the effect on nuclear and mitochondrial pathways, and iron-containing proteins and genes to evaluate anti-metastasis and chemoresistance. A lung carcinoma mouse model was used for in vivo studies. Results: Our findings revealed that Def induced cytotoxicity, effectively chelated intracellular iron, and triggered apoptosis through the increase in phosphatidylserine externalization and caspase 3 activity. Additionally, Def caused G0/G1 cell cycle arrest by downregulating the ribonucleotide reductase catalytic subunit. Furthermore, Def perturbed mitochondrial function by promoting the production of reactive oxygen species and the inhibition of glutathione as a measurement of ferroptosis activation. Def demonstrated inhibitory effects on cell migration in scratch assays, which was supported by the upregulation of n-myc downstream-regulated gene 1 and downregulation of the epidermal growth factor receptor protein. Also, Def downregulated one of the main markers of chemoresistance, the ABCB1 gene. In vivo experiments using a lung carcinoma mouse model showed that Def treatment did not affect the animal's body weight and showed a significant decrease in tumor growth. Conclusions: This investigation lays the groundwork for unraveling Def action's molecular targets and mechanisms in lung carcinoma, particularly within iron-related pathways, pointing out its anti-metastasis and anti-chemoresistance effect.

Activation of Heme Metabolism Promotes Tissue Health After Intraarticular Injury or Surgical Exposure.

Posttraumatic osteoarthritis (PTOA) is a well-recognized public health burden without any disease modifying treatment. This occurs despite noted advances in surgical care in the past 50 years. Mitochondrial oxidative damage pathways initiate PTOA after severe injuries like intraarticular fracture that often require surgery and contribute to PTOA after less severe injuries that may or may not require surgery like meniscal injuries. When considering the mitochondrial and redox environment of the injured joint, we hypothesized that activation of heme metabolism, previously associated with healing in many settings, would cause prototypic mitochondrial reprogramming effects in cartilage ideally suited for use at the time of injury repair. Activation of heme metabolism can be accomplished through the gasotransmitter carbon monoxide (CO), which activates hemeoxygenase-1 (HO1) and subsequent heme metabolism. In this study, we employed unique carbon monoxide (CO)-containing foam (COF) to stimulate heme metabolism and restore chondrocyte oxygen metabolism in vitro and in vivo . Doxycycline-inducible, chondrocyte-specific HO1 overexpressing transgenic mice show similar mitochondrial reprogramming after induction compared to COF. CO is retained at least 24 h after COF injection into stifle joints and induces sustained increases in heme metabolism. Lastly, intraarticular injection of COF causes key redox outcomes without any adverse safety outcomes in rabbit stifle joints ex vivo and in vivo . We propose that activation of heme metabolism is an ideal adjuvant to trauma care that replenishes chondrocyte mitochondrial metabolism and restores redox homeostasis.

Synthesis, anticancer activity, and mechanistic investigations of aryl-alkyl diorganotin arylformylhydrazone complexes

Diorganotin acylhydrazone complexes with mitochondrial targeting demonstrate significant potential as replacements for platinum-based complexes due to their potent anticancer properties. Twelve methylphenyltin arylformylhydrazone complexes have been synthesized by microwave “one-pot” reaction. The complexes have been characterized by FT-IR, multinuclear NMR (1H, 13C, and 119Sn), TGA, and HRMS. Crystal structures were determined for 10 out of the 12 complexes under study. Structures 1 through 8, 10 and 12 possessed a central symmetric structure of a di-nuclear Sn2O2 tetrahedral ring. All complexes were tested for their inhibitory activity against human cell lines NCI-H460, MCF-7, and HepG2. Complex 8 exhibited the most effective inhibitory effect on HepG2 cells, with an IC50 value of 1.34 ± 0.04 μM. Preliminary studies on the anticancer mechanism suggest that complex 8 induces apoptosis in HepG2 cells via the mitochondrial pathway, accompanied by G2/M phase cell cycle arrest.

Unveiling tribal treasures: myco-chemical characterization and pharmacological evaluation of an unexplored Russula pers. species.

During extensive field explorations of the Lateritic area in West Bengal, one remarkable wild Russuloid macrofungus, ethnically termed "Kend Patra," was collected. The species was known to enrich the diet of the local people, being considered as income source for some tribal groups. Using morphological characters and molecular analysis of this collection, provide a unique placement of the taxon in the Russula subgenus Compactae(Fr.) Bon. Further in order to find functional constituents for biopharma applications, methanolic extract was prepared that shows the existence of a substantial amounts of phenol, flavonoid, ascorbic acid and carotenoids. Antioxidant activity was determined where the fraction demonstrated strong DPPH, ABTS, and nitric oxide radical scavenging activities, high Fe2+ ion chelating ability, and a reducing power with EC50 values ranging from 538.69 to 891.75µg/ml. The extract was found to be effective against Listeria monocytogenes, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Salmonella typhi and Staphylococcus aureus. In addition, the extract exhibited potent anticancer activities as it inhibited A549 cell proliferation, caused morphological changes, elevated ROS levels, hindered the clonogenic ability and migratory potential of cancerous cells, arrested cell cycle progression at S phase, and induced apoptosis by modulating the intrinsic mitochondrial pathway. Overall, this study contributes a new species to the world's myco-diversity and presents an exciting opportunity for future researchers to conduct comprehensive investigations on this unique species in order to uncover potential new medications for human use.

Changes in meat quality of Esox Lucius during postmortem storage: Based on the lysosomal-mitochondrial apoptotic pathway

In this study, we explored the correlation between the lysosome–mitochondrial apoptosis pathway and fish softening, as well as the correlation between ferritin degradation and lysosomal iron changes. The results indicated that ferritin levels gradually decreased, lysosomal iron first increased and then decreased and tended to stabilize, and lysosomal membrane stability significantly decreased (p < 0.05). Spearman's analysis suggested that an increase in lysosomal iron was associated with ferritin degradation. Lysosomal instability promoted the release of cathepsin D, thereby increasing the release of Bid and Bax, and inhibiting the expression of Bcl-2. Subsequently, caspase-9/−3 was activated. In addition, transmission electron microscopy revealed ultrastructural damage to mitochondria and cell nuclei, which are morphological features of apoptosis during post-mortem storage. Moreover, TUNEL staining confirmed the occurrence of apoptosis. We concluded that the lysosome– mitochondrial apoptosis pathway was active during the storage of Esox Lucius, in which ferritin degradation and increased lysosomal iron were key factors inducing lysosomal damage, and cathepsin D released by lysosomes was a key factor connecting lysosomes and mitochondria.

Curcumin attenuates ochratoxin A and hypoxia co-induced liver injury in grass carp (Ctenopharyngodon idella) by dual targeting endoplasmic reticulum stress and apoptosis via reducing ROS content

BackgroundOchratoxin A (OTA) is a toxin widely found in aquafeed ingredients, and hypoxia is a common problem in fish farming. In practice, aquatic animals tend to be more sensitive to hypoxia while feeds are contaminated with OTA, but no studies exist in this area. This research investigated the multiple biotoxicities of OTA and hypoxia combined on the liver of grass carp and explored the mitigating effect of curcumin (CUR).MethodsA total of 720 healthy juvenile grass carp (11.06 ± 0.05 g) were selected and assigned randomly to 4 experimental groups: control group (without OTA and CUR), 1.2 mg/kg OTA group, 400 mg/kg CUR group, and 1.2 mg/kg OTA + 400 mg/kg CUR group with three replicates each for 60 d. Subsequently, 32 fish were selected, divided into normoxia (18 fish) and hypoxia (18 fish) groups, and subjected to hypoxia stress for 96 h.ResultsCUR can attenuate histopathological damage caused by coming to OTA and hypoxia by reducing vacuolation and nuclear excursion. The alleviation of this damage was associated with the attenuation of apoptosis in the mitochondrial pathway by decreasing the expression of the pro-apoptotic proteins Caspase 3, 8, 9, Bax, and Apaf1 while increasing the expression of the anti-apoptotic protein Bcl-2, and attenuation of endoplasmic reticulum stress (ERS) by reducing Grp78 expression and chop levels. This may be attributed to the fact that the addition of CUR increased the levels of catalase (CAT) and glutathione reductase (GSH), increased antioxidant capacity, and ensured the proper functioning of respiratory chain complexes I and II, which in turn reduced the high production of reactive oxygen species (ROS), thus alleviating apoptosis and ERS.ConclusionsIn conclusion, our data demonstrate the effectiveness of CUR in attenuating liver injury caused by the combination of OTA and hypoxia. This study confirms the feasibility and efficacy of adding natural products to mitigate toxic damage to aquatic animals.

Screening of FDA-approved Drugs against Protein Thymidine Kinase 2 Using Machine Learning Method Validated Applying Molecular Dynamics and Free Energy Landscape Calculation

Background: Thymidine kinase 2 (TK2) is a crucial enzyme in the mitochondrial pyrimidine salvage pathway, strongly associated with several mitochondrial diseases. Current treatments frequently damage mitochondria, leading to a decrease in cellular energy output. Objective: This study aimed to use computational approaches to identify inhibitors of TK2 that could prevent these harmful consequences. Method: The initial screening process entailed the application of machine learning algorithms, more particularly a Random Forest model, which was trained on 189 FDA-approved drugs and decoy datasets obtained from the DUD-E database. Its purpose was to identify potential inhibitors. The molecular docking technique was employed to evaluate the affinity of the chosen medicines towards TK2. Molecular dynamics (MD) simulations lasting 100 nanoseconds were employed to conduct additional validation by examining the dynamic interactions between the top-found compounds and TK2. Results: Three hit compounds (3168, 5209502, and 135402009) were identified through the screening process for their high affinity for TK2. Compound 5209502 had the most stable interaction with the lowest root-mean-square deviation (RMSD) in the molecular dynamics (MD) simulations and maintained 12 hydrogen bonds consistently. MM/GBSA computations verified that 5209502 exhibited the strongest binding affinity with a binding free energy of -62.14 kcal/mol, which was notably lower than that of the control ligand. Conclusion: Compound 5209502 is a promising candidate for additional experimental evaluation because of its notable stability and great affinity for TK2. This chemical may provide a focused and less harmful treatment for mitochondrial illnesses linked to TK2 malfunction.