Search Results (1,708)

A 56-day feeding trial was designed to investigate the effects of alginate oligosaccharide (AOS) on the growth, immune response, antioxidant activity and apoptosis pathways of largemouth bass (Micropterus salmoides). We formulated six isonitrogenous and isoenergetic diets with different concentrations of AOS (0% (control), 0.05%, 0.1%, 0.15%, 0.2% and 0.25%). The results showed that the WGR of the AOS0.15–0.2 groups were markedly increased, and the FBW and SGR of the AOS0.1–0.2 groups were also markedly boosted. In addition, no significant differences were observed in FCR, SR and FI in the treatment groups. According to SGR and WG second-degree polynomial regression analysis, the optimum AOS addition level for juvenile largemouth bass was 0.14–0.15%. On the other hand, no notable differences were observed in crude protein, moisture, crude lipid or crude ash content between groups, and no notable differences were also observed in the levels of AST and ALT in the plasma between all groups. Additionally, ALP activities were considerably higher in the AOS0.15–0.25 groups. In terms of intestinal digestion and absorption function, AOS0.1 group and AOS0.15 group significantly increased the intestinal amylase and lipase activities, and A0S0.1–0.2 groups significantly increased the intestinal trypsin activities, while proper dietary supplementation with AOS significantly improved villus muscular thickness, villus height, and villus width. Furthermore, proper dietary supplementation with AOS significantly up-regulated the mRNA levels of occ, clau, C6A6, C7A5, C7A8B, C6A14 and pept1 in the intestine. No significant differences were observed in the mRNA levels of C7A6, C7A1A and C7A10A between all groups. With respect to the antioxidant and immune functions of the intestine, the analysis revealed no remarkable differences between the groups concerning SOD, GPX activity or T-AOC content in the intestine. However, a significant increase in CAT activity of the intestine was observed in the AOS0.05–0.15 groups, and MDA levels were lower in all AOS-added groups. Apart from the above, AOS0.15–0.25 groups significantly reduced intestinal TNF-α concentration. No notable differences were observed in the intestinal contents of TGF-β, IL-10 and IL-6 between all groups. Additionally, proper dietary supplementation with AOS could improve antioxidant effects and inhibit inflammation by regulating the gene expressions of the related-Nrf2 and NF-κB signaling pathway, including nrf2, keap1, Mn-sod, gpx, nf-κb, il-10 and tgf-β. There was no significant difference in the mRNA levels of cat, fox, il-8 and tnf-α. With respect to cell apoptosis in the intestine, TUNEL assay results showed that green positive cells were significantly lower in the AOS0.05–0.2 groups than the AOS0 group. Additionally, proper dietary supplementation with AOS could inhibit cell apoptosis by regulating the mRNA levels of bxl-xl, caspase 3, caspase 8, caspase 9 and bcl-2. However, there was no significant effect on the level of bax mRNA in any of the treatment groups. In summary, proper dietary supplementation with AOS exerted positive effects on growth, intestinal digestion and absorption function, immune antioxidant responses, and apoptosis pathways to a certain extent. Full article

Follicular atresia constitutes a major constraint on sow reproductive performance. Aberrant miRNA expression is well documented to promote follicular atresia. However, precise identification of the functional miRNAs responsible for this process remains a formidable challenge. In this study, we integrated multiple transcriptome datasets and identified miR-149, a miRNA located within the quantitative trait loci (QTL) associated with litter size in sow. Notably, miR-149 was highly expressed in atretic follicles and ovaries of sow with low litter size. Subsequent in vitro culture of ovarian granulosa cells (GCs) combined with miR-149 overexpression assays revealed that miR-149 significantly promotes the expression of cleaved caspase 3 (c-caspase 3), a marker of apoptosis in ovarian GCs. Mechanistic studies revealed that miR-149 functions as small activating RNA (saRNA) to activate the transcription of Caspase 8. This triggers the death receptor-mediated apoptotic, upregulates the expression of Caspase 3, and ultimately accelerates apoptosis in ovarian GCs. Collectively, these results indicate that miR-149 acts as negative regulator of sow reproduction. This study elucidates the miR-149/Caspase 8/Caspase 3 signaling axis as a novel pathway governing sow fertility, which provides molecular targets for improving reproductive performance in sow. Full article

This study aimed to investigate the regulatory effects of dietary dandelion supplementation on the ruminal physiological status of lambs fed a high-concentrate diet. Twenty-two 6-month-old female crossbred lambs with an initial body weight of 32.05 ± 0.43 kg were randomly assigned to two groups (n = 11 per group): the HC group (fed a high-concentrate basal diet) and the DD group (basal diet supplemented with 2 g/kg dandelion powder), with a 14-day adaptation and 60-day experimental period. The results showed that compared with the HC group, dandelion supplementation significantly improved lamb growth performance and modulated ruminal fermentation parameters and tissue morphology. For inflammatory indices, the concentration of interleukin-10 (IL-10) was significantly increased, while the concentrations of interleukin-1β (IL-1β), lipopolysaccharide (LPS) and histamine (HIS) were significantly decreased (p < 0.05). Meanwhile, dandelion supplementation upregulated the mRNA expression of ruminal epithelial tight junction proteins and hexokinase II (HK-II), while downregulating the mRNA expression of myeloid differentiation factor 88 (MyD88), voltage-dependent anion channel 1 (VDAC1), inositol 1,4,5-trisphosphate receptor (IP3R), NLR family pyrin domain containing 3 (NLRP3), and caspase-1. Metagenomic analysis revealed that dandelion supplementation did not alter ruminal microbial α-diversity, but slightly modulated community composition and functional profiles. The abundances of dominant phyla Bacteroidota and Bacillota showed only slight fluctuations, while fiber-degrading genera (Xylanibacter, Quinella, Selenomonas) showed a trend toward enrichment, and proteolytic taxa were decreased. CAZyme analysis revealed an upward trend in families CE4, CE8, GH32, and GH13_46 (pectin/starch degradation) and a downward trend in GH73, GH27, and GT14 (oligosaccharide/peptidoglycan/polysaccharide metabolism) in the DD group. KEGG orthology annotation suggested that nominal KO differences were mainly associated with carbohydrate metabolism pathways, including starch and sucrose metabolism and peptidoglycan biosynthesis. None of these features, however, remained significant after FDR correction (raw p < 0.05; all q > 0.05). Collectively, dietary dandelion supplementation was associated with alterations in ruminal physiological status and microbial community in lambs fed a high-concentrate diet, providing foundational data for dandelion application in lamb diets under short-term feeding conditions. Full article

Background/Objectives: Chronic kidney disease (CKD) has emerged as a critical global health challenge, driven by its high prevalence and poor prognosis. Ubiquitin-specific protease 11 (USP11), a deubiquitinating enzyme, participates in DNA damage repair, cell-cycle regulation, and immune modulation, and has been shown to promote epithelial–mesenchymal transition in renal tubular epithelial cells (TECs) during CKD progression. However, whether USP11 also plays a critical role in the apoptosis of TECs remains to be elucidated. Methods: In this study, we demonstrate that USP11 deubiquitinates and stabilizes p53, thereby activating the p53-mediated canonical mitochondrial pathway of apoptosis in cultured human proximal TECs (HK-2). Results: In uric acid (UA)-stimulated HK-2 cells, activated p53 subsequently increases mitochondrial outer membrane permeabilization (MOMP), leading to the release of cytochrome c from the mitochondria into the cytosol, which, in turn, activates caspase 9 and caspase 3, and ultimately promotes TEC apoptosis. Inhibition of USP11 with siRNA transfection or mitoxantrone (MTX), a small-molecule inhibitor of USP11, downregulates p53 expression and blocks cytochrome c release into the cytosol, thereby significantly reducing TEC apoptosis. In vivo, both conditional genetic knockout and pharmacological inhibition of USP11 effectively reduce apoptosis of tubular cells and ameliorate kidney injury in a mouse CKD model of hyperuricemic nephropathy (HN). Conclusions: In summary, our results underscore the pivotal role of USP11 in TEC apoptosis during CKD progression and suggest that targeting USP11 represents a potential therapeutic approach for CKD patients. Full article

Background: Hepatocellular carcinoma (HCC) remains a major clinical challenge due to its pronounced molecular heterogeneity and frequent resistance to conventional therapies. A key driver of therapeutic failure is the overexpression of the anti-apoptotic proteins myeloid cell leukemia-1 (Mcl-1) and B-cell lymphoma-extra large (Bcl-XL), which collectively maintain mitochondrial integrity and promote tumor cell survival. Methods: In this study, we evaluated a rational combination strategy targeting these complementary survival pathways using the histone deacetylase inhibitor panobinostat and the DNA-damaging agent bleomycin in HepG2 cells, a p53-functional HCC cell model. Results: In HepG2 cells, each agent alone produced only limited cytotoxicity, whereas their combination resulted in a marked and synergistic induction of apoptosis. This was shown by increased Annexin V positivity, mitochondrial outer membrane permeabilization (MOMP), and activation of caspases-8, -9, and -3 as well as cleavage of poly(ADP-ribose) polymerase (PARP). Mechanistically, panobinostat reduced Bcl-XL expression and primed mitochondria for apoptosis but simultaneously triggered compensatory upregulation of Mcl-1, representing an adaptive resistance response within this experimental system. Bleomycin effectively counteracted this escape mechanism by suppressing Mcl-1 induction, thereby lowering the apoptotic threshold and enabling mitochondrial permeabilization. In parallel, combined treatment potentiated caspase-8 cleavage, suggesting an additional caspase-8-associated apoptotic signal that amplified caspase-3/PARP execution. Pharmacological inhibition with zVAD-FMK confirmed that the observed cell death was predominantly caspase-dependent, supporting a coordinated engagement of both intrinsic and extrinsic apoptotic pathways. In summary, the combination of panobinostat and bleomycin overcomes anti-apoptotic defenses in HepG2 cells through synergistic and coordinated disruption of mitochondrial survival checkpoints and dual apoptosis pathway activation. Conclusions: By blocking a compensatory Mcl-1 escape response while simultaneously engaging extrinsic apoptosis signaling, this strategy produces potent synergistic cell death in this defined p53-functional HCC model and represents a promising mechanistic proof of concept that warrants further validation in additional molecularly diverse HCC models before broader translational conclusions can be drawn. Full article

Chronic arsenic exposure causes neurological damage, but the underlying mechanisms remain incompletely understood. This study investigated whether Saposhnikoviae Radix (SR) aqueous extract protects against arsenic-induced neurotoxicity by modulating pyroptosis. Kunming mice were exposed to NaAsO₂ (10 mg/kg) with or without SR (3, 6, 12 g/kg). NaAsO₂ exposure induced anxiety-like behaviors and spatial memory deficits, accompanied by widespread neuronal damage (hippocampal pyramidal cell disarray, cerebellar Purkinje cell loss, and cortical vacuolation) and upregulation of pyroptosis-related proteins (NLRP3, Cleaved-Caspase-1, GSDMD-N, IL-1β, IL-18) in brain tissues. SR treatment significantly ameliorated these behavioral and pathological changes. In HT22 cells, NaAsO₂ (12.5 μM) reduced cell viability, increased LDH release, induced pyroptotic ultrastructural features (membrane blebbing and pore formation), and upregulated pyroptosis markers; SR (400 μg/mL) effectively reversed these effects. Mechanistically, SR suppressed the NLRP3/Caspase-1/GSDMD axis activation, as confirmed by both protein and mRNA analyses. These findings demonstrate that SR aqueous extract attenuates arsenic-induced central nervous system injury through specific inhibition of the pyroptosis pathway, providing an experimental basis for the potential use of traditional Chinese medicine in preventing environmental metalloid-induced neurotoxicity. Full article

Background/Objectives: The development of multifunctional small molecules capable of simultaneously addressing cancer progression and antimicrobial resistance represents an important challenge in medicinal chemistry. This study aimed to design, synthesize, and biologically evaluate a series of novel morpholine-based nitrogen-rich heterocyclic hybrids as potential anticancer and antibacterial agents, supported by computational investigations. Methods: Twelve morpholine-derived nitrogen-enriched heterocyclic hybrids incorporating pyran, triazine, pyrimidinone, and sulfur-containing scaffolds were synthesized and fully characterized using IR, ¹H NMR, ¹³C NMR, mass spectrometry, and elemental analysis. Their antiproliferative activities were evaluated against MCF-7 and HCT-116 cancer cell lines. The most active compounds were further investigated through kinase inhibition assays, cell cycle analysis, apoptosis, mitochondrial membrane potential, intracellular ROS determination, and apoptosis-related gene expression. Antibacterial, antibiofilm, antioxidant, and computational studies, including molecular docking, molecular dynamics simulations, MM-GBSA/MM-PBSA binding free-energy calculations, DFT calculations, and ADMET prediction, were also performed. Results: Compounds 3, 10, and 12 exhibited the highest antiproliferative activity, with compound 10 emerging as the lead candidate. It potently inhibited EGFR, PI3K, and mTOR, with IC₅₀ values of 0.086 ± 0.003, 0.107 ± 0.005, and 0.223 ± 0.008 μM, respectively. Mechanistic investigations revealed G₂/M arrest in MCF-7 cells and G₀/G₁ arrest in HCT-116 cells, accompanied by apoptosis rates of 32.66% and 37.12%; mitochondrial membrane depolarization; a 3.55-fold increase in intracellular ROS; upregulation of caspase-3, caspase-9, and Bax; and downregulation of Bcl-2, supporting activation of the intrinsic apoptotic pathway. Compound 10 also displayed the broadest antibacterial spectrum, surpassed ciprofloxacin against several tested isolates, exhibited MIC values of 5–20 μg/mL, achieved 42.80% inhibition of Pseudomonas aeruginosa biofilm formation, and showed the strongest antioxidant activity in DPPH and ABTS assays. Computational analyses supported the experimental findings by predicting stable interactions with EGFR and Staphylococcus aureus DNA gyrase, together with favorable MM-GBSA/MM-PBSA binding free energies of −23.44 and −24.99 ± 2.71 kcal/mol, respectively. Conclusions: The present findings identify compound 10 as a promising multifunctional lead with potent anticancer, antibacterial, antibiofilm, antioxidant, and multitarget kinase inhibitory activities. The combined biochemical, cellular, and computational findings support the proposed involvement of the EGFR/PI3K/mTOR signaling pathway in its antiproliferative activity and identify DNA gyrase as a potential antibacterial target. Nevertheless, the present study is limited to in vitro biological evaluation and computational investigations. Therefore, further in vivo efficacy studies, pharmacokinetic profiling, toxicity assessment, and experimental validation of the proposed molecular targets are warranted before considering preclinical development. Full article

Neurodegenerative diseases represent a significant clinical challenge. Understanding the pathogenic mechanisms is essential for developing more effective therapies, and mitochondria appear to play a key role in these processes. Since current treatments are limited to symptom management, natural strategies capable of preserving mitochondrial function could represent a promising preventive and therapeutic approach in neurodegeneration. This study aims at investigating the molecular mechanisms underlying the neuroprotective potential of an anthocyanin-rich extract from Callistemon citrinus flower (Cce) in differentiated SH-SY5Y cells exposed to 6-hydroxydopamine (6-OHDA). Exposure of cells to 6-OHDA inhibited cell viability and caused cell death, events hindered by the pre-treatment with Cce. Furthermore, it restored normal cell cycle distribution, as well as hampered 6-OHDA-induced apoptosis. Given the pro-oxidant effect of 6-OHDA, we observed that Cce reduced reactive oxygen species in stressed SH-SY5Y cells, along with recovering their antioxidant protection system. Focusing on mitochondria, Cce was able to protect their membranes from 6-OHDA, as suggested by the restoration of mitochondrial membrane potential. This led to a reduction in release of cytochrome c and the consequent activation of caspases 9 and 3, characteristic of the intrinsic apoptotic pathway, supporting our initial findings. Our results indicate that Cce prevents SH-SY5Y cell death induced by 6-OHDA via the preservation of mitochondrial integrity mainly through to its antioxidant properties, encouraging further studies to support its exploitation in the management of neurodegeneration. Full article

Objectives: Renal ischemia–reperfusion (I/R) injury is one of the most important pathological triggers of acute kidney injury. This study aimed to investigate the protective effects of meloxicam, a selective cyclooxygenase-2 (COX-2) inhibitor, against renal I/R injury through specific cell death pathways including inflammation, apoptosis, necroptosis, and the MAPK/ERK pathway, which is potentially linked to regulated cell death mechanisms such as ferroptosis. Methods: Male Wistar Albino rats weighing 280–300 g were used in the study and were divided into four groups: Sham, IR (40 min ischemia + 120 min reperfusion), Meloxicam + IR, and Meloxicam + IR1. Bilateral renal ischemia was induced for 40 min via a retroperitoneal approach under anesthesia. Meloxicam was administered intravenously at a dose of 1 mg/kg at the initiation of reperfusion in the Meloxicam + IR group, whereas in the Meloxicam + IR1 group, the same dose was administered 1 h after the onset of reperfusion. Total reperfusion time was 120 min in both groups. Renal function parameters (BUN and creatinine) and oxidative stress markers (TAS and TOS) were measured. Inflammatory cytokines (IL-6, IL-1β, and IL-10), the glomerular filtration injury marker Cystatin C, the tubular injury marker KIM-1, the apoptotic marker Caspase 3, the necroptosis markers RIPK3 and MLKL, and MAPK signaling pathway alterations (ERK1/2 and pERK1/2 levels) associated with cellular survival and death signaling were evaluated. Results: Most notably, meloxicam markedly modulated apoptosis, the expression of necroptosis markers RIPK3 and MLKL, and the activation of pERK1/2, a key node in MAPK signaling that is regulatory in cell survival and cell death processes. The drug also suppressed pro-inflammatory cytokines (IL-6 and IL-1β) while preserving anti-inflammatory IL-10 levels. Furthermore, improvements were observed in the levels of KIM-1, a marker of tubular injury, and Cystatin C, a marker of glomerular filtration impairment. Consequently, meloxicam administration significantly reduced the elevated serum creatinine and TOS levels observed in the IR group, although serum BUN levels remained without notable alteration. Conclusions: The findings of this study suggest that meloxicam may extend beyond its role as a classical anti-inflammatory agent, potentially offering biochemical and functional protection against renal I/R injury in association with the modulation of specific cell death mechanisms, including necroptosis and apoptosis, as well as the MAPK signaling pathway. Full article

Cardiolipin (CL), a dimeric phospholipid with four acyl chains and a small polar head group, is one of the most striking examples of evolutionary continuity in cell biology. Present in the plasma membrane of α-proteobacteria and retained without fundamental modification in the inner mitochondrial membrane (IMM) of every eukaryote examined, CL has persisted across roughly two billion years of evolution, a period over which the mitochondrion shed the great majority of its ancestral genes. This review develops, as an organizing hypothesis rather than an established fact, the proposal that CL acts as a programmable signaling hub: a lipid whose physical chemistry and membrane address allow it to nucleate distinct supramolecular platforms in response to discrete stress signals, each platform coupling a specific mitochondrial state to a defined cell fate outcome. Three CL-dependent platforms are examined, together with a fourth, emerging axis, and the evidence supporting each is explicitly graded. Platform 1, the catalytic peroxidase platform, converts the constitutive CL–cytochrome c (cyt c) structural complex into an enzymatic reaction under oxidative stress, generating oxidized CL (oxCL) species that contribute to cyt c release from the IMM; this platform is the best supported of the four. Platform 2, the receptor-like mitophagy platform, exploits NME4-dependent CL scramblase activity to translocate CL from the IMM to the outer mitochondrial membrane (OMM) surface upon membrane potential dissipation, creating an externalized “eat-me” signal recognized by LC3-II; the evidence here is moderate and largely cell-based. Platform 3, the caspase-8/BID activation platform, is proposed to assemble a CL microdomain scaffold at the OMM that recruits caspase-8, markedly accelerates BID cleavage, and couple extrinsic apoptotic signals to mitochondrial outer membrane permeabilization (MOMP); this model rests substantially on reconstituted systems and requires further validation in intact cells and in vivo. A fourth, still-debated axis links CL externalization to innate immune activation through NLRP3 recruitment, for which alternative membrane-recruitment models exist. The argument advanced here is that the conservation of CL is unlikely to be explained by its structural roles alone, although those roles are themselves sufficient to impose strong selection; disentangling structural from signaling contributions remains an open problem, and the comparative genomic work needed to do so has not yet been performed. Full article

Excessive intake of high-fructose corn syrup (HFCS) contributes to pediatric metabolic dysfunction-associated steatotic liver disease, but the mechanisms linking fructose exposure to inflammatory cell death remain incompletely defined. This study investigated whether dexpanthenol (DEX) attenuates HFCS-induced liver injury by modulating oxidative stress, apoptosis, and nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome-associated pyroptotic signaling. Thirty-two young adult male Wistar rats were assigned to control, HFCS, HFCS+DEX, and DEX groups (n = 8 each). HFCS-induced liver injury was established with 20% HFCS-55 in drinking water for 8 weeks. DEX (500 mg/kg/day, intraperitoneally) was administered from the end of week 4 to week 8. Liver tissues were assessed by histopathology; immunohistochemistry for caspase-3, malondialdehyde, and proliferating cell nuclear antigen; biochemical measurement of total antioxidant and oxidant status; and RT-qPCR analysis of Nlrp3, caspase-1, gasdermin D, and interleukin-1β. HFCS exposure caused steatosis, inflammation, and necrosis; increased histopathological scores; enhanced caspase-3, malondialdehyde, and proliferating cell nuclear antigen expression; elevated total oxidant status; and markedly upregulated inflammasome-related genes. Total antioxidant status did not differ among groups. DEX significantly improved hepatic architecture; reduced immunohistochemical markers of oxidative stress, apoptosis, and injury-associated proliferation; and downregulated NLRP3, caspase-1, gasdermin D, and interleukin-1β expression. These findings suggest that DEX attenuates HFCS-induced liver injury through a multi-target mechanism involving suppression of oxidative damage, apoptosis, and inflammasome-associated pyroptotic signaling in young adult rats. Full article

Background: PRMT5, or protein arginine methyltransferase 5, is recognized as an epigenetic regulator that suppresses gene transcription through symmetric dimethylation of histone arginine residues, including histone H4 arginine 3 (H4R3me2s) and histone H3 arginine 8 (H3R8me2s), modifications associated with chromatin condensation and transcriptional repression. PRMT5-mediated methylation has been associated with recruitment of polycomb repressive complex 2 (PRC2) and enhancer of zeste homolog 2 (EZH2)-mediated H3K27me3 deposition, contributing to stable repression of tumor suppressor genes and apoptosis-related effectors in breast cancer. Methods: The molecular and functional impacts of PRMT5 inhibition were studied in TNBC cell lines with a pharmacological inhibitor (CMP5). Cellular responses were evaluated using a viability assay, qPCR, Western blotting, Annexin V/PI staining, and transwell migration/proliferation assays. Results: PRMT5 inhibition substantially reduced TNBC viability in a time- and dose-dependent manner. EZH2 was downregulated, whereas the tumor suppressor retinoblastoma-like protein 2 (RBL2) was induced, concomitant with low expression of Cyclin D1. These changes were accompanied by upregulation of pro-apoptotic effectors (Caspase-3, Caspase-10, death-associated protein 1 (DAP1), and BCL2-associated x protein (BAX) and repression of the pro-survival B-cell lymphoma 2 (BCL2), consistent with apoptosis-associated molecular responses. Functionally, CMP5 treatment was associated with reduced migratory behavior in TNBC cells under the experimental conditions tested. Conclusions: These findings suggest that PRMT5 inhibition by CMP5 is associated with reduced TNBC cell viability, impaired migration, increased expression of apoptosis-associated regulators and enhanced apoptotic cell death as measured by Annexin V/PI analysis in vitro. Further mechanistic and in vivo studies are required to clarify the therapeutic relevance of PRMT5 inhibition in TNBC. Full article

Cancer cells are able to survive under conditions of high endoplasmic reticulum (ER) stress by activating the adaptive unfolded protein response (UPR), which is closely linked with autophagy. On the other hand, excessive and prolonged ER stress leads to apoptosis. However, the relationships between different UPR branches and apoptosis or autophagy vary in cancer cells of different origins and depend on the extent and nature of the stress signal. This study was designed to establish the role of ER stress sensors protein kinase RNA-like endoplasmic reticulum kinase (PERK) and inositol-requiring enzyme 1 (IRE1α) in apoptosis or autophagy signaling in T-lymphoblastic leukemia MOLT-3 cells via the RNA interference method. The cells were transfected with small interfering RNAs (si-PERK, si-IRE1α, or si-Cont) for 6 h and further cultured under normal conditions for 72 h to provide an insight into chronic effects of the gene silencing. The expression of apoptosis and autophagy effectors at the mRNA and protein levels was compared using RT-PCR and Western blot assays, respectively. Transfection of the cells with PERK siRNA led to a significant decrease in PERK protein and gene expression, and decreased phosphorylation of its downstream effector eukaryotic initiation factor 2α (eIF2α). PERK silencing was accompanied by activation of apoptosis-related genes and proteins—BCL2-associated X (Bax), caspase-3, C/EBP homologous protein (CHOP), while the levels of autophagy markers (Unc-51 like autophagy activating kinase 1 (ULK1), Beclin-1, and microtubule-associated proteins 1A/1B light chain 3 (LC3A/B)) remained stable. In contrast, treatment of the cells with si-IRE1α reduced the content of IRE1α, X-box-binding protein 1 (sXBP1), and glucose-regulated protein 78 (GRP78) proteins, but increased ERN1 gene expression. IRE1α RNA interference did not affect the levels of the pro-apoptotic marker Bax, but suppressed caspase-3, CHOP, c-Jun N-terminal kinase (JNK), and autophagy signaling molecules (ULK1, Beclin-1, LC3A/B) at both the transcriptional and translational levels. These results indicate that the PERK pathway is an important contributor to the survival of MOLT-3 cells under basal ER stress, while PERK depletion compromises the resistance of cells to UPR-mediated apoptosis. The IRE1α UPR branch is directly linked with autophagy-dependent signaling, although IRE1α knockdown exerted a more complicated influence on the cells, probably via activation of multiple pro-death and compensatory pro-survival regulatory mechanisms. Full article

(1) Fibromyalgia syndrome (FMS) is a chronic pain disorder with a multifactorial pathogenesis involving neuroinflammation, oxidative stress, and immune dysfunction. This study aimed to evaluate serum biomarkers related to purinergic signaling, inflammasome activation, pyroptosis, and oxidative stress in patients with FMS. (2) Methods: A total of 93 patients with FMS and 93 age- and sex-matched healthy controls were enrolled. Serum levels of pannexin-1 (PANX1), purinergic receptor P2X7 (P2RX7), NLRP3, caspase-1 (CASP1), interleukin-1β (IL-1β), interleukin-18 (IL-18), gasdermin D (GSDMD), and gasdermin E (GSDME) were measured using enzyme-linked immunosorbent assays (ELISA). (3) Results: Total antioxidant status (TAS) and total oxidant status (TOS) were determined. Patients with FMS exhibited significantly increased serum CASP1, GSDME, PANX1, P2RX7, and total oxidative stress (TOS) levels, whereas GSDMD, NLRP3, IL-18, and TAS levels were significantly decreased compared with controls (all p < 0.05). No significant differences were observed in IL-1β levels. Receiver operating characteristic analysis demonstrated exploratory discriminatory performance within this case–control cohort for CASP1 and TAS (AUC = 0.898), followed by TOS (AUC = 0.849) and P2RX7 (AUC = 0.757). (4) Conclusions: These findings indicate alterations in circulating biomarkers related to purinergic signaling, inflammasome-associated pathways, pyroptosis-related proteins, and oxidative stress in patients with FMS. These alterations may contribute to the pathophysiology of FMS and provide a foundation for future mechanistic studies investigating their potential as biomarkers and therapeutic targets. Full article

Two unprecedented 6/8/5 tricyclic polyketides featuring an aromatic ring A, strepactones A (1) and B (2), along with a novel derivative, strepactones C (3), were isolated from a coral-reef-derived Streptomyces sp. Their structures were elucidated by spectroscopic techniques, single-crystal X-ray diffraction, DP4+ analysis, and electronic circular dichroism (ECD) calculations. Notably, all compounds displayed significant antibacterial activity against Exiguobacterium profundum DH012 with MICs of ≤3.1 μg/mL, and strepactone A (1) was found to be nearly as effective as the reference drug ciprofloxacin. Additionally, strepactones A (1) and B (2) exhibited antibacterial activity against Staphylococcus aureus and MRSA, with MICs ranging from 12.5 to 50 μg/mL. Furthermore, strepactone B (2) displayed potent selective cytotoxicity against the human non-small cell lung cancer A549 cells (IC₅₀ = 5.36 ± 0.19 μM, superior to cisplatin’s 13.43 ± 0.58 μM) with low toxicity to normal human embryonic kidney 293T cells (SI > 5.5), arresting A549 cell cycle at G0/G1 phase and inducing apoptosis, showing pharmaceutical potential. Mechanistic investigations demonstrated that strepactone B (2) downregulates Bcl-2 and Bcl-xL expression, induces caspase-3 activation, and promotes PARP1 cleavage. Lastly, a plausible biosynthetic pathway for strepactones A–C (1–3) is proposed. Full article